Import PCG-C into sys/contrib

[FreeBSD/FreeBSD.git] / sys / cam / ctl / ctl.c

/*-
 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
 *
 * Copyright (c) 2003-2009 Silicon Graphics International Corp.
 * Copyright (c) 2012 The FreeBSD Foundation
 * Copyright (c) 2014-2017 Alexander Motin <mav@FreeBSD.org>
 * Copyright (c) 2017 Jakub Wojciech Klama <jceel@FreeBSD.org>
 * Copyright (c) 2018 Marcelo Araujo <araujo@FreeBSD.org>
 * All rights reserved.
 *
 * Portions of this software were developed by Edward Tomasz Napierala
 * under sponsorship from the FreeBSD Foundation.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions, and the following disclaimer,
 *    without modification.
 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
 *    substantially similar to the "NO WARRANTY" disclaimer below
 *    ("Disclaimer") and any redistribution must be conditioned upon
 *    including a substantially similar Disclaimer requirement for further
 *    binary redistribution.
 *
 * NO WARRANTY
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGES.
 *
 * $Id$
 */
/*
 * CAM Target Layer, a SCSI device emulation subsystem.
 *
 * Author: Ken Merry <ken@FreeBSD.org>
 */

#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/ctype.h>
#include <sys/kernel.h>
#include <sys/types.h>
#include <sys/kthread.h>
#include <sys/bio.h>
#include <sys/fcntl.h>
#include <sys/lock.h>
#include <sys/module.h>
#include <sys/mutex.h>
#include <sys/condvar.h>
#include <sys/malloc.h>
#include <sys/conf.h>
#include <sys/ioccom.h>
#include <sys/queue.h>
#include <sys/sbuf.h>
#include <sys/smp.h>
#include <sys/endian.h>
#include <sys/proc.h>
#include <sys/sched.h>
#include <sys/sysctl.h>
#include <sys/nv.h>
#include <sys/dnv.h>
#include <vm/uma.h>

#include <cam/cam.h>
#include <cam/scsi/scsi_all.h>
#include <cam/scsi/scsi_cd.h>
#include <cam/scsi/scsi_da.h>
#include <cam/ctl/ctl_io.h>
#include <cam/ctl/ctl.h>
#include <cam/ctl/ctl_frontend.h>
#include <cam/ctl/ctl_util.h>
#include <cam/ctl/ctl_backend.h>
#include <cam/ctl/ctl_ioctl.h>
#include <cam/ctl/ctl_ha.h>
#include <cam/ctl/ctl_private.h>
#include <cam/ctl/ctl_debug.h>
#include <cam/ctl/ctl_scsi_all.h>
#include <cam/ctl/ctl_error.h>

struct ctl_softc *control_softc = NULL;

/*
 * Template mode pages.
 */

/*
 * Note that these are default values only.  The actual values will be
 * filled in when the user does a mode sense.
 */
const static struct scsi_da_rw_recovery_page rw_er_page_default = {
        /*page_code*/SMS_RW_ERROR_RECOVERY_PAGE,
        /*page_length*/sizeof(struct scsi_da_rw_recovery_page) - 2,
        /*byte3*/SMS_RWER_AWRE|SMS_RWER_ARRE,
        /*read_retry_count*/0,
        /*correction_span*/0,
        /*head_offset_count*/0,
        /*data_strobe_offset_cnt*/0,
        /*byte8*/SMS_RWER_LBPERE,
        /*write_retry_count*/0,
        /*reserved2*/0,
        /*recovery_time_limit*/{0, 0},
};

const static struct scsi_da_rw_recovery_page rw_er_page_changeable = {
        /*page_code*/SMS_RW_ERROR_RECOVERY_PAGE,
        /*page_length*/sizeof(struct scsi_da_rw_recovery_page) - 2,
        /*byte3*/SMS_RWER_PER,
        /*read_retry_count*/0,
        /*correction_span*/0,
        /*head_offset_count*/0,
        /*data_strobe_offset_cnt*/0,
        /*byte8*/SMS_RWER_LBPERE,
        /*write_retry_count*/0,
        /*reserved2*/0,
        /*recovery_time_limit*/{0, 0},
};

const static struct scsi_format_page format_page_default = {
        /*page_code*/SMS_FORMAT_DEVICE_PAGE,
        /*page_length*/sizeof(struct scsi_format_page) - 2,
        /*tracks_per_zone*/ {0, 0},
        /*alt_sectors_per_zone*/ {0, 0},
        /*alt_tracks_per_zone*/ {0, 0},
        /*alt_tracks_per_lun*/ {0, 0},
        /*sectors_per_track*/ {(CTL_DEFAULT_SECTORS_PER_TRACK >> 8) & 0xff,
                                CTL_DEFAULT_SECTORS_PER_TRACK & 0xff},
        /*bytes_per_sector*/ {0, 0},
        /*interleave*/ {0, 0},
        /*track_skew*/ {0, 0},
        /*cylinder_skew*/ {0, 0},
        /*flags*/ SFP_HSEC,
        /*reserved*/ {0, 0, 0}
};

const static struct scsi_format_page format_page_changeable = {
        /*page_code*/SMS_FORMAT_DEVICE_PAGE,
        /*page_length*/sizeof(struct scsi_format_page) - 2,
        /*tracks_per_zone*/ {0, 0},
        /*alt_sectors_per_zone*/ {0, 0},
        /*alt_tracks_per_zone*/ {0, 0},
        /*alt_tracks_per_lun*/ {0, 0},
        /*sectors_per_track*/ {0, 0},
        /*bytes_per_sector*/ {0, 0},
        /*interleave*/ {0, 0},
        /*track_skew*/ {0, 0},
        /*cylinder_skew*/ {0, 0},
        /*flags*/ 0,
        /*reserved*/ {0, 0, 0}
};

const static struct scsi_rigid_disk_page rigid_disk_page_default = {
        /*page_code*/SMS_RIGID_DISK_PAGE,
        /*page_length*/sizeof(struct scsi_rigid_disk_page) - 2,
        /*cylinders*/ {0, 0, 0},
        /*heads*/ CTL_DEFAULT_HEADS,
        /*start_write_precomp*/ {0, 0, 0},
        /*start_reduced_current*/ {0, 0, 0},
        /*step_rate*/ {0, 0},
        /*landing_zone_cylinder*/ {0, 0, 0},
        /*rpl*/ SRDP_RPL_DISABLED,
        /*rotational_offset*/ 0,
        /*reserved1*/ 0,
        /*rotation_rate*/ {(CTL_DEFAULT_ROTATION_RATE >> 8) & 0xff,
                           CTL_DEFAULT_ROTATION_RATE & 0xff},
        /*reserved2*/ {0, 0}
};

const static struct scsi_rigid_disk_page rigid_disk_page_changeable = {
        /*page_code*/SMS_RIGID_DISK_PAGE,
        /*page_length*/sizeof(struct scsi_rigid_disk_page) - 2,
        /*cylinders*/ {0, 0, 0},
        /*heads*/ 0,
        /*start_write_precomp*/ {0, 0, 0},
        /*start_reduced_current*/ {0, 0, 0},
        /*step_rate*/ {0, 0},
        /*landing_zone_cylinder*/ {0, 0, 0},
        /*rpl*/ 0,
        /*rotational_offset*/ 0,
        /*reserved1*/ 0,
        /*rotation_rate*/ {0, 0},
        /*reserved2*/ {0, 0}
};

const static struct scsi_da_verify_recovery_page verify_er_page_default = {
        /*page_code*/SMS_VERIFY_ERROR_RECOVERY_PAGE,
        /*page_length*/sizeof(struct scsi_da_verify_recovery_page) - 2,
        /*byte3*/0,
        /*read_retry_count*/0,
        /*reserved*/{ 0, 0, 0, 0, 0, 0 },
        /*recovery_time_limit*/{0, 0},
};

const static struct scsi_da_verify_recovery_page verify_er_page_changeable = {
        /*page_code*/SMS_VERIFY_ERROR_RECOVERY_PAGE,
        /*page_length*/sizeof(struct scsi_da_verify_recovery_page) - 2,
        /*byte3*/SMS_VER_PER,
        /*read_retry_count*/0,
        /*reserved*/{ 0, 0, 0, 0, 0, 0 },
        /*recovery_time_limit*/{0, 0},
};

const static struct scsi_caching_page caching_page_default = {
        /*page_code*/SMS_CACHING_PAGE,
        /*page_length*/sizeof(struct scsi_caching_page) - 2,
        /*flags1*/ SCP_DISC | SCP_WCE,
        /*ret_priority*/ 0,
        /*disable_pf_transfer_len*/ {0xff, 0xff},
        /*min_prefetch*/ {0, 0},
        /*max_prefetch*/ {0xff, 0xff},
        /*max_pf_ceiling*/ {0xff, 0xff},
        /*flags2*/ 0,
        /*cache_segments*/ 0,
        /*cache_seg_size*/ {0, 0},
        /*reserved*/ 0,
        /*non_cache_seg_size*/ {0, 0, 0}
};

const static struct scsi_caching_page caching_page_changeable = {
        /*page_code*/SMS_CACHING_PAGE,
        /*page_length*/sizeof(struct scsi_caching_page) - 2,
        /*flags1*/ SCP_WCE | SCP_RCD,
        /*ret_priority*/ 0,
        /*disable_pf_transfer_len*/ {0, 0},
        /*min_prefetch*/ {0, 0},
        /*max_prefetch*/ {0, 0},
        /*max_pf_ceiling*/ {0, 0},
        /*flags2*/ 0,
        /*cache_segments*/ 0,
        /*cache_seg_size*/ {0, 0},
        /*reserved*/ 0,
        /*non_cache_seg_size*/ {0, 0, 0}
};

const static struct scsi_control_page control_page_default = {
        /*page_code*/SMS_CONTROL_MODE_PAGE,
        /*page_length*/sizeof(struct scsi_control_page) - 2,
        /*rlec*/0,
        /*queue_flags*/SCP_QUEUE_ALG_RESTRICTED,
        /*eca_and_aen*/0,
        /*flags4*/SCP_TAS,
        /*aen_holdoff_period*/{0, 0},
        /*busy_timeout_period*/{0, 0},
        /*extended_selftest_completion_time*/{0, 0}
};

const static struct scsi_control_page control_page_changeable = {
        /*page_code*/SMS_CONTROL_MODE_PAGE,
        /*page_length*/sizeof(struct scsi_control_page) - 2,
        /*rlec*/SCP_DSENSE,
        /*queue_flags*/SCP_QUEUE_ALG_MASK | SCP_NUAR,
        /*eca_and_aen*/SCP_SWP,
        /*flags4*/0,
        /*aen_holdoff_period*/{0, 0},
        /*busy_timeout_period*/{0, 0},
        /*extended_selftest_completion_time*/{0, 0}
};

#define CTL_CEM_LEN     (sizeof(struct scsi_control_ext_page) - 4)

const static struct scsi_control_ext_page control_ext_page_default = {
        /*page_code*/SMS_CONTROL_MODE_PAGE | SMPH_SPF,
        /*subpage_code*/0x01,
        /*page_length*/{CTL_CEM_LEN >> 8, CTL_CEM_LEN},
        /*flags*/0,
        /*prio*/0,
        /*max_sense*/0
};

const static struct scsi_control_ext_page control_ext_page_changeable = {
        /*page_code*/SMS_CONTROL_MODE_PAGE | SMPH_SPF,
        /*subpage_code*/0x01,
        /*page_length*/{CTL_CEM_LEN >> 8, CTL_CEM_LEN},
        /*flags*/0,
        /*prio*/0,
        /*max_sense*/0xff
};

const static struct scsi_info_exceptions_page ie_page_default = {
        /*page_code*/SMS_INFO_EXCEPTIONS_PAGE,
        /*page_length*/sizeof(struct scsi_info_exceptions_page) - 2,
        /*info_flags*/SIEP_FLAGS_EWASC,
        /*mrie*/SIEP_MRIE_NO,
        /*interval_timer*/{0, 0, 0, 0},
        /*report_count*/{0, 0, 0, 1}
};

const static struct scsi_info_exceptions_page ie_page_changeable = {
        /*page_code*/SMS_INFO_EXCEPTIONS_PAGE,
        /*page_length*/sizeof(struct scsi_info_exceptions_page) - 2,
        /*info_flags*/SIEP_FLAGS_EWASC | SIEP_FLAGS_DEXCPT | SIEP_FLAGS_TEST |
            SIEP_FLAGS_LOGERR,
        /*mrie*/0x0f,
        /*interval_timer*/{0xff, 0xff, 0xff, 0xff},
        /*report_count*/{0xff, 0xff, 0xff, 0xff}
};

#define CTL_LBPM_LEN    (sizeof(struct ctl_logical_block_provisioning_page) - 4)

const static struct ctl_logical_block_provisioning_page lbp_page_default = {{
        /*page_code*/SMS_INFO_EXCEPTIONS_PAGE | SMPH_SPF,
        /*subpage_code*/0x02,
        /*page_length*/{CTL_LBPM_LEN >> 8, CTL_LBPM_LEN},
        /*flags*/0,
        /*reserved*/{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
        /*descr*/{}},
        {{/*flags*/0,
          /*resource*/0x01,
          /*reserved*/{0, 0},
          /*count*/{0, 0, 0, 0}},
         {/*flags*/0,
          /*resource*/0x02,
          /*reserved*/{0, 0},
          /*count*/{0, 0, 0, 0}},
         {/*flags*/0,
          /*resource*/0xf1,
          /*reserved*/{0, 0},
          /*count*/{0, 0, 0, 0}},
         {/*flags*/0,
          /*resource*/0xf2,
          /*reserved*/{0, 0},
          /*count*/{0, 0, 0, 0}}
        }
};

const static struct ctl_logical_block_provisioning_page lbp_page_changeable = {{
        /*page_code*/SMS_INFO_EXCEPTIONS_PAGE | SMPH_SPF,
        /*subpage_code*/0x02,
        /*page_length*/{CTL_LBPM_LEN >> 8, CTL_LBPM_LEN},
        /*flags*/SLBPP_SITUA,
        /*reserved*/{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
        /*descr*/{}},
        {{/*flags*/0,
          /*resource*/0,
          /*reserved*/{0, 0},
          /*count*/{0, 0, 0, 0}},
         {/*flags*/0,
          /*resource*/0,
          /*reserved*/{0, 0},
          /*count*/{0, 0, 0, 0}},
         {/*flags*/0,
          /*resource*/0,
          /*reserved*/{0, 0},
          /*count*/{0, 0, 0, 0}},
         {/*flags*/0,
          /*resource*/0,
          /*reserved*/{0, 0},
          /*count*/{0, 0, 0, 0}}
        }
};

const static struct scsi_cddvd_capabilities_page cddvd_page_default = {
        /*page_code*/SMS_CDDVD_CAPS_PAGE,
        /*page_length*/sizeof(struct scsi_cddvd_capabilities_page) - 2,
        /*caps1*/0x3f,
        /*caps2*/0x00,
        /*caps3*/0xf0,
        /*caps4*/0x00,
        /*caps5*/0x29,
        /*caps6*/0x00,
        /*obsolete*/{0, 0},
        /*nvol_levels*/{0, 0},
        /*buffer_size*/{8, 0},
        /*obsolete2*/{0, 0},
        /*reserved*/0,
        /*digital*/0,
        /*obsolete3*/0,
        /*copy_management*/0,
        /*reserved2*/0,
        /*rotation_control*/0,
        /*cur_write_speed*/0,
        /*num_speed_descr*/0,
};

const static struct scsi_cddvd_capabilities_page cddvd_page_changeable = {
        /*page_code*/SMS_CDDVD_CAPS_PAGE,
        /*page_length*/sizeof(struct scsi_cddvd_capabilities_page) - 2,
        /*caps1*/0,
        /*caps2*/0,
        /*caps3*/0,
        /*caps4*/0,
        /*caps5*/0,
        /*caps6*/0,
        /*obsolete*/{0, 0},
        /*nvol_levels*/{0, 0},
        /*buffer_size*/{0, 0},
        /*obsolete2*/{0, 0},
        /*reserved*/0,
        /*digital*/0,
        /*obsolete3*/0,
        /*copy_management*/0,
        /*reserved2*/0,
        /*rotation_control*/0,
        /*cur_write_speed*/0,
        /*num_speed_descr*/0,
};

SYSCTL_NODE(_kern_cam, OID_AUTO, ctl, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
    "CAM Target Layer");
static int worker_threads = -1;
SYSCTL_INT(_kern_cam_ctl, OID_AUTO, worker_threads, CTLFLAG_RDTUN,
    &worker_threads, 1, "Number of worker threads");
static int ctl_debug = CTL_DEBUG_NONE;
SYSCTL_INT(_kern_cam_ctl, OID_AUTO, debug, CTLFLAG_RWTUN,
    &ctl_debug, 0, "Enabled debug flags");
static int ctl_lun_map_size = 1024;
SYSCTL_INT(_kern_cam_ctl, OID_AUTO, lun_map_size, CTLFLAG_RWTUN,
    &ctl_lun_map_size, 0, "Size of per-port LUN map (max LUN + 1)");
#ifdef  CTL_TIME_IO
static int ctl_time_io_secs = CTL_TIME_IO_DEFAULT_SECS;
SYSCTL_INT(_kern_cam_ctl, OID_AUTO, time_io_secs, CTLFLAG_RWTUN,
    &ctl_time_io_secs, 0, "Log requests taking more seconds");
#endif

/*
 * Maximum number of LUNs we support.  MUST be a power of 2.
 */
#define CTL_DEFAULT_MAX_LUNS    1024
static int ctl_max_luns = CTL_DEFAULT_MAX_LUNS;
TUNABLE_INT("kern.cam.ctl.max_luns", &ctl_max_luns);
SYSCTL_INT(_kern_cam_ctl, OID_AUTO, max_luns, CTLFLAG_RDTUN,
    &ctl_max_luns, CTL_DEFAULT_MAX_LUNS, "Maximum number of LUNs");

/*
 * Maximum number of ports registered at one time.
 */
#define CTL_DEFAULT_MAX_PORTS           256
static int ctl_max_ports = CTL_DEFAULT_MAX_PORTS;
TUNABLE_INT("kern.cam.ctl.max_ports", &ctl_max_ports);
SYSCTL_INT(_kern_cam_ctl, OID_AUTO, max_ports, CTLFLAG_RDTUN,
    &ctl_max_ports, CTL_DEFAULT_MAX_LUNS, "Maximum number of ports");

/*
 * Maximum number of initiators we support.
 */
#define CTL_MAX_INITIATORS      (CTL_MAX_INIT_PER_PORT * ctl_max_ports)

/*
 * Supported pages (0x00), Serial number (0x80), Device ID (0x83),
 * Extended INQUIRY Data (0x86), Mode Page Policy (0x87),
 * SCSI Ports (0x88), Third-party Copy (0x8F), SCSI Feature Sets (0x92),
 * Block limits (0xB0), Block Device Characteristics (0xB1) and
 * Logical Block Provisioning (0xB2)
 */
#define SCSI_EVPD_NUM_SUPPORTED_PAGES   11

static void ctl_isc_event_handler(ctl_ha_channel chanel, ctl_ha_event event,
                                  int param);
static void ctl_copy_sense_data(union ctl_ha_msg *src, union ctl_io *dest);
static void ctl_copy_sense_data_back(union ctl_io *src, union ctl_ha_msg *dest);
static int ctl_init(void);
static int ctl_shutdown(void);
static int ctl_open(struct cdev *dev, int flags, int fmt, struct thread *td);
static int ctl_close(struct cdev *dev, int flags, int fmt, struct thread *td);
static void ctl_serialize_other_sc_cmd(struct ctl_scsiio *ctsio);
static void ctl_ioctl_fill_ooa(struct ctl_lun *lun, uint32_t *cur_fill_num,
                              struct ctl_ooa *ooa_hdr,
                              struct ctl_ooa_entry *kern_entries);
static int ctl_ioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flag,
                     struct thread *td);
static int ctl_enable_lun(struct ctl_lun *lun);
static int ctl_disable_lun(struct ctl_lun *lun);
static int ctl_free_lun(struct ctl_lun *lun);

static int ctl_do_mode_select(union ctl_io *io);
static int ctl_pro_preempt(struct ctl_softc *softc, struct ctl_lun *lun,
                           uint64_t res_key, uint64_t sa_res_key,
                           uint8_t type, uint32_t residx,
                           struct ctl_scsiio *ctsio,
                           struct scsi_per_res_out *cdb,
                           struct scsi_per_res_out_parms* param);
static void ctl_pro_preempt_other(struct ctl_lun *lun,
                                  union ctl_ha_msg *msg);
static void ctl_hndl_per_res_out_on_other_sc(union ctl_io *io);
static int ctl_inquiry_evpd_supported(struct ctl_scsiio *ctsio, int alloc_len);
static int ctl_inquiry_evpd_serial(struct ctl_scsiio *ctsio, int alloc_len);
static int ctl_inquiry_evpd_devid(struct ctl_scsiio *ctsio, int alloc_len);
static int ctl_inquiry_evpd_eid(struct ctl_scsiio *ctsio, int alloc_len);
static int ctl_inquiry_evpd_mpp(struct ctl_scsiio *ctsio, int alloc_len);
static int ctl_inquiry_evpd_scsi_ports(struct ctl_scsiio *ctsio,
                                         int alloc_len);
static int ctl_inquiry_evpd_sfs(struct ctl_scsiio *ctsio, int alloc_len);
static int ctl_inquiry_evpd_block_limits(struct ctl_scsiio *ctsio,
                                         int alloc_len);
static int ctl_inquiry_evpd_bdc(struct ctl_scsiio *ctsio, int alloc_len);
static int ctl_inquiry_evpd_lbp(struct ctl_scsiio *ctsio, int alloc_len);
static int ctl_inquiry_evpd(struct ctl_scsiio *ctsio);
static int ctl_inquiry_std(struct ctl_scsiio *ctsio);
static int ctl_get_lba_len(union ctl_io *io, uint64_t *lba, uint64_t *len);
static ctl_action ctl_extent_check(union ctl_io *io1, union ctl_io *io2,
    bool seq);
static ctl_action ctl_extent_check_seq(union ctl_io *io1, union ctl_io *io2);
static ctl_action ctl_check_for_blockage(struct ctl_lun *lun,
    union ctl_io *pending_io, union ctl_io *ooa_io);
static ctl_action ctl_check_ooa(struct ctl_lun *lun, union ctl_io *pending_io,
                                union ctl_io **starting_io);
static void ctl_try_unblock_io(struct ctl_lun *lun, union ctl_io *io,
    bool skip);
static void ctl_try_unblock_others(struct ctl_lun *lun, union ctl_io *io,
    bool skip);
static int ctl_scsiio_lun_check(struct ctl_lun *lun,
                                const struct ctl_cmd_entry *entry,
                                struct ctl_scsiio *ctsio);
static void ctl_failover_lun(union ctl_io *io);
static int ctl_scsiio_precheck(struct ctl_softc *ctl_softc,
                               struct ctl_scsiio *ctsio);
static int ctl_scsiio(struct ctl_scsiio *ctsio);

static int ctl_target_reset(union ctl_io *io);
static void ctl_do_lun_reset(struct ctl_lun *lun, uint32_t initidx,
                         ctl_ua_type ua_type);
static int ctl_lun_reset(union ctl_io *io);
static int ctl_abort_task(union ctl_io *io);
static int ctl_abort_task_set(union ctl_io *io);
static int ctl_query_task(union ctl_io *io, int task_set);
static void ctl_i_t_nexus_loss(struct ctl_softc *softc, uint32_t initidx,
                              ctl_ua_type ua_type);
static int ctl_i_t_nexus_reset(union ctl_io *io);
static int ctl_query_async_event(union ctl_io *io);
static void ctl_run_task(union ctl_io *io);
#ifdef CTL_IO_DELAY
static void ctl_datamove_timer_wakeup(void *arg);
static void ctl_done_timer_wakeup(void *arg);
#endif /* CTL_IO_DELAY */

static void ctl_send_datamove_done(union ctl_io *io, int have_lock);
static void ctl_datamove_remote_write_cb(struct ctl_ha_dt_req *rq);
static int ctl_datamove_remote_dm_write_cb(union ctl_io *io);
static void ctl_datamove_remote_write(union ctl_io *io);
static int ctl_datamove_remote_dm_read_cb(union ctl_io *io);
static void ctl_datamove_remote_read_cb(struct ctl_ha_dt_req *rq);
static int ctl_datamove_remote_sgl_setup(union ctl_io *io);
static int ctl_datamove_remote_xfer(union ctl_io *io, unsigned command,
                                    ctl_ha_dt_cb callback);
static void ctl_datamove_remote_read(union ctl_io *io);
static void ctl_datamove_remote(union ctl_io *io);
static void ctl_process_done(union ctl_io *io);
static void ctl_thresh_thread(void *arg);
static void ctl_work_thread(void *arg);
static void ctl_enqueue_incoming(union ctl_io *io);
static void ctl_enqueue_rtr(union ctl_io *io);
static void ctl_enqueue_done(union ctl_io *io);
static void ctl_enqueue_isc(union ctl_io *io);
static const struct ctl_cmd_entry *
    ctl_get_cmd_entry(struct ctl_scsiio *ctsio, int *sa);
static const struct ctl_cmd_entry *
    ctl_validate_command(struct ctl_scsiio *ctsio);
static int ctl_cmd_applicable(uint8_t lun_type,
    const struct ctl_cmd_entry *entry);
static int ctl_ha_init(void);
static int ctl_ha_shutdown(void);

static uint64_t ctl_get_prkey(struct ctl_lun *lun, uint32_t residx);
static void ctl_clr_prkey(struct ctl_lun *lun, uint32_t residx);
static void ctl_alloc_prkey(struct ctl_lun *lun, uint32_t residx);
static void ctl_set_prkey(struct ctl_lun *lun, uint32_t residx, uint64_t key);

/*
 * Load the serialization table.  This isn't very pretty, but is probably
 * the easiest way to do it.
 */
#include "ctl_ser_table.c"

/*
 * We only need to define open, close and ioctl routines for this driver.
 */
static struct cdevsw ctl_cdevsw = {
        .d_version =    D_VERSION,
        .d_flags =      0,
        .d_open =       ctl_open,
        .d_close =      ctl_close,
        .d_ioctl =      ctl_ioctl,
        .d_name =       "ctl",
};


MALLOC_DEFINE(M_CTL, "ctlmem", "Memory used for CTL");

static int ctl_module_event_handler(module_t, int /*modeventtype_t*/, void *);

static moduledata_t ctl_moduledata = {
        "ctl",
        ctl_module_event_handler,
        NULL
};

DECLARE_MODULE(ctl, ctl_moduledata, SI_SUB_CONFIGURE, SI_ORDER_THIRD);
MODULE_VERSION(ctl, 1);

static struct ctl_frontend ha_frontend =
{
        .name = "ha",
        .init = ctl_ha_init,
        .shutdown = ctl_ha_shutdown,
};

static int
ctl_ha_init(void)
{
        struct ctl_softc *softc = control_softc;

        if (ctl_pool_create(softc, "othersc", CTL_POOL_ENTRIES_OTHER_SC,
                            &softc->othersc_pool) != 0)
                return (ENOMEM);
        if (ctl_ha_msg_init(softc) != CTL_HA_STATUS_SUCCESS) {
                ctl_pool_free(softc->othersc_pool);
                return (EIO);
        }
        if (ctl_ha_msg_register(CTL_HA_CHAN_CTL, ctl_isc_event_handler)
            != CTL_HA_STATUS_SUCCESS) {
                ctl_ha_msg_destroy(softc);
                ctl_pool_free(softc->othersc_pool);
                return (EIO);
        }
        return (0);
};

static int
ctl_ha_shutdown(void)
{
        struct ctl_softc *softc = control_softc;
        struct ctl_port *port;

        ctl_ha_msg_shutdown(softc);
        if (ctl_ha_msg_deregister(CTL_HA_CHAN_CTL) != CTL_HA_STATUS_SUCCESS)
                return (EIO);
        if (ctl_ha_msg_destroy(softc) != CTL_HA_STATUS_SUCCESS)
                return (EIO);
        ctl_pool_free(softc->othersc_pool);
        while ((port = STAILQ_FIRST(&ha_frontend.port_list)) != NULL) {
                ctl_port_deregister(port);
                free(port->port_name, M_CTL);
                free(port, M_CTL);
        }
        return (0);
};

static void
ctl_ha_datamove(union ctl_io *io)
{
        struct ctl_lun *lun = CTL_LUN(io);
        struct ctl_sg_entry *sgl;
        union ctl_ha_msg msg;
        uint32_t sg_entries_sent;
        int do_sg_copy, i, j;

        memset(&msg.dt, 0, sizeof(msg.dt));
        msg.hdr.msg_type = CTL_MSG_DATAMOVE;
        msg.hdr.original_sc = io->io_hdr.remote_io;
        msg.hdr.serializing_sc = io;
        msg.hdr.nexus = io->io_hdr.nexus;
        msg.hdr.status = io->io_hdr.status;
        msg.dt.flags = io->io_hdr.flags;

        /*
         * We convert everything into a S/G list here.  We can't
         * pass by reference, only by value between controllers.
         * So we can't pass a pointer to the S/G list, only as many
         * S/G entries as we can fit in here.  If it's possible for
         * us to get more than CTL_HA_MAX_SG_ENTRIES S/G entries,
         * then we need to break this up into multiple transfers.
         */
        if (io->scsiio.kern_sg_entries == 0) {
                msg.dt.kern_sg_entries = 1;
#if 0
                if (io->io_hdr.flags & CTL_FLAG_BUS_ADDR) {
                        msg.dt.sg_list[0].addr = io->scsiio.kern_data_ptr;
                } else {
                        /* XXX KDM use busdma here! */
                        msg.dt.sg_list[0].addr =
                            (void *)vtophys(io->scsiio.kern_data_ptr);
                }
#else
                KASSERT((io->io_hdr.flags & CTL_FLAG_BUS_ADDR) == 0,
                    ("HA does not support BUS_ADDR"));
                msg.dt.sg_list[0].addr = io->scsiio.kern_data_ptr;
#endif
                msg.dt.sg_list[0].len = io->scsiio.kern_data_len;
                do_sg_copy = 0;
        } else {
                msg.dt.kern_sg_entries = io->scsiio.kern_sg_entries;
                do_sg_copy = 1;
        }

        msg.dt.kern_data_len = io->scsiio.kern_data_len;
        msg.dt.kern_total_len = io->scsiio.kern_total_len;
        msg.dt.kern_data_resid = io->scsiio.kern_data_resid;
        msg.dt.kern_rel_offset = io->scsiio.kern_rel_offset;
        msg.dt.sg_sequence = 0;

        /*
         * Loop until we've sent all of the S/G entries.  On the
         * other end, we'll recompose these S/G entries into one
         * contiguous list before processing.
         */
        for (sg_entries_sent = 0; sg_entries_sent < msg.dt.kern_sg_entries;
            msg.dt.sg_sequence++) {
                msg.dt.cur_sg_entries = MIN((sizeof(msg.dt.sg_list) /
                    sizeof(msg.dt.sg_list[0])),
                    msg.dt.kern_sg_entries - sg_entries_sent);
                if (do_sg_copy != 0) {
                        sgl = (struct ctl_sg_entry *)io->scsiio.kern_data_ptr;
                        for (i = sg_entries_sent, j = 0;
                             i < msg.dt.cur_sg_entries; i++, j++) {
#if 0
                                if (io->io_hdr.flags & CTL_FLAG_BUS_ADDR) {
                                        msg.dt.sg_list[j].addr = sgl[i].addr;
                                } else {
                                        /* XXX KDM use busdma here! */
                                        msg.dt.sg_list[j].addr =
                                            (void *)vtophys(sgl[i].addr);
                                }
#else
                                KASSERT((io->io_hdr.flags &
                                    CTL_FLAG_BUS_ADDR) == 0,
                                    ("HA does not support BUS_ADDR"));
                                msg.dt.sg_list[j].addr = sgl[i].addr;
#endif
                                msg.dt.sg_list[j].len = sgl[i].len;
                        }
                }

                sg_entries_sent += msg.dt.cur_sg_entries;
                msg.dt.sg_last = (sg_entries_sent >= msg.dt.kern_sg_entries);
                if (ctl_ha_msg_send(CTL_HA_CHAN_CTL, &msg,
                    sizeof(msg.dt) - sizeof(msg.dt.sg_list) +
                    sizeof(struct ctl_sg_entry) * msg.dt.cur_sg_entries,
                    M_WAITOK) > CTL_HA_STATUS_SUCCESS) {
                        io->io_hdr.port_status = 31341;
                        io->scsiio.be_move_done(io);
                        return;
                }
                msg.dt.sent_sg_entries = sg_entries_sent;
        }

        /*
         * Officially handover the request from us to peer.
         * If failover has just happened, then we must return error.
         * If failover happen just after, then it is not our problem.
         */
        if (lun)
                mtx_lock(&lun->lun_lock);
        if (io->io_hdr.flags & CTL_FLAG_FAILOVER) {
                if (lun)
                        mtx_unlock(&lun->lun_lock);
                io->io_hdr.port_status = 31342;
                io->scsiio.be_move_done(io);
                return;
        }
        io->io_hdr.flags &= ~CTL_FLAG_IO_ACTIVE;
        io->io_hdr.flags |= CTL_FLAG_DMA_INPROG;
        if (lun)
                mtx_unlock(&lun->lun_lock);
}

static void
ctl_ha_done(union ctl_io *io)
{
        union ctl_ha_msg msg;

        if (io->io_hdr.io_type == CTL_IO_SCSI) {
                memset(&msg, 0, sizeof(msg));
                msg.hdr.msg_type = CTL_MSG_FINISH_IO;
                msg.hdr.original_sc = io->io_hdr.remote_io;
                msg.hdr.nexus = io->io_hdr.nexus;
                msg.hdr.status = io->io_hdr.status;
                msg.scsi.scsi_status = io->scsiio.scsi_status;
                msg.scsi.tag_num = io->scsiio.tag_num;
                msg.scsi.tag_type = io->scsiio.tag_type;
                msg.scsi.sense_len = io->scsiio.sense_len;
                memcpy(&msg.scsi.sense_data, &io->scsiio.sense_data,
                    io->scsiio.sense_len);
                ctl_ha_msg_send(CTL_HA_CHAN_CTL, &msg,
                    sizeof(msg.scsi) - sizeof(msg.scsi.sense_data) +
                    msg.scsi.sense_len, M_WAITOK);
        }
        ctl_free_io(io);
}

static void
ctl_isc_handler_finish_xfer(struct ctl_softc *ctl_softc,
                            union ctl_ha_msg *msg_info)
{
        struct ctl_scsiio *ctsio;

        if (msg_info->hdr.original_sc == NULL) {
                printf("%s: original_sc == NULL!\n", __func__);
                /* XXX KDM now what? */
                return;
        }

        ctsio = &msg_info->hdr.original_sc->scsiio;
        ctsio->io_hdr.flags |= CTL_FLAG_IO_ACTIVE;
        ctsio->io_hdr.msg_type = CTL_MSG_FINISH_IO;
        ctsio->io_hdr.status = msg_info->hdr.status;
        ctsio->scsi_status = msg_info->scsi.scsi_status;
        ctsio->sense_len = msg_info->scsi.sense_len;
        memcpy(&ctsio->sense_data, &msg_info->scsi.sense_data,
               msg_info->scsi.sense_len);
        ctl_enqueue_isc((union ctl_io *)ctsio);
}

static void
ctl_isc_handler_finish_ser_only(struct ctl_softc *ctl_softc,
                                union ctl_ha_msg *msg_info)
{
        struct ctl_scsiio *ctsio;

        if (msg_info->hdr.serializing_sc == NULL) {
                printf("%s: serializing_sc == NULL!\n", __func__);
                /* XXX KDM now what? */
                return;
        }

        ctsio = &msg_info->hdr.serializing_sc->scsiio;
        ctsio->io_hdr.msg_type = CTL_MSG_FINISH_IO;
        ctl_enqueue_isc((union ctl_io *)ctsio);
}

void
ctl_isc_announce_lun(struct ctl_lun *lun)
{
        struct ctl_softc *softc = lun->ctl_softc;
        union ctl_ha_msg *msg;
        struct ctl_ha_msg_lun_pr_key pr_key;
        int i, k;

        if (softc->ha_link != CTL_HA_LINK_ONLINE)
                return;
        mtx_lock(&lun->lun_lock);
        i = sizeof(msg->lun);
        if (lun->lun_devid)
                i += lun->lun_devid->len;
        i += sizeof(pr_key) * lun->pr_key_count;
alloc:
        mtx_unlock(&lun->lun_lock);
        msg = malloc(i, M_CTL, M_WAITOK);
        mtx_lock(&lun->lun_lock);
        k = sizeof(msg->lun);
        if (lun->lun_devid)
                k += lun->lun_devid->len;
        k += sizeof(pr_key) * lun->pr_key_count;
        if (i < k) {
                free(msg, M_CTL);
                i = k;
                goto alloc;
        }
        bzero(&msg->lun, sizeof(msg->lun));
        msg->hdr.msg_type = CTL_MSG_LUN_SYNC;
        msg->hdr.nexus.targ_lun = lun->lun;
        msg->hdr.nexus.targ_mapped_lun = lun->lun;
        msg->lun.flags = lun->flags;
        msg->lun.pr_generation = lun->pr_generation;
        msg->lun.pr_res_idx = lun->pr_res_idx;
        msg->lun.pr_res_type = lun->pr_res_type;
        msg->lun.pr_key_count = lun->pr_key_count;
        i = 0;
        if (lun->lun_devid) {
                msg->lun.lun_devid_len = lun->lun_devid->len;
                memcpy(&msg->lun.data[i], lun->lun_devid->data,
                    msg->lun.lun_devid_len);
                i += msg->lun.lun_devid_len;
        }
        for (k = 0; k < CTL_MAX_INITIATORS; k++) {
                if ((pr_key.pr_key = ctl_get_prkey(lun, k)) == 0)
                        continue;
                pr_key.pr_iid = k;
                memcpy(&msg->lun.data[i], &pr_key, sizeof(pr_key));
                i += sizeof(pr_key);
        }
        mtx_unlock(&lun->lun_lock);
        ctl_ha_msg_send(CTL_HA_CHAN_CTL, &msg->port, sizeof(msg->port) + i,
            M_WAITOK);
        free(msg, M_CTL);

        if (lun->flags & CTL_LUN_PRIMARY_SC) {
                for (i = 0; i < CTL_NUM_MODE_PAGES; i++) {
                        ctl_isc_announce_mode(lun, -1,
                            lun->mode_pages.index[i].page_code & SMPH_PC_MASK,
                            lun->mode_pages.index[i].subpage);
                }
        }
}

void
ctl_isc_announce_port(struct ctl_port *port)
{
        struct ctl_softc *softc = port->ctl_softc;
        union ctl_ha_msg *msg;
        int i;

        if (port->targ_port < softc->port_min ||
            port->targ_port >= softc->port_max ||
            softc->ha_link != CTL_HA_LINK_ONLINE)
                return;
        i = sizeof(msg->port) + strlen(port->port_name) + 1;
        if (port->lun_map)
                i += port->lun_map_size * sizeof(uint32_t);
        if (port->port_devid)
                i += port->port_devid->len;
        if (port->target_devid)
                i += port->target_devid->len;
        if (port->init_devid)
                i += port->init_devid->len;
        msg = malloc(i, M_CTL, M_WAITOK);
        bzero(&msg->port, sizeof(msg->port));
        msg->hdr.msg_type = CTL_MSG_PORT_SYNC;
        msg->hdr.nexus.targ_port = port->targ_port;
        msg->port.port_type = port->port_type;
        msg->port.physical_port = port->physical_port;
        msg->port.virtual_port = port->virtual_port;
        msg->port.status = port->status;
        i = 0;
        msg->port.name_len = sprintf(&msg->port.data[i],
            "%d:%s", softc->ha_id, port->port_name) + 1;
        i += msg->port.name_len;
        if (port->lun_map) {
                msg->port.lun_map_len = port->lun_map_size * sizeof(uint32_t);
                memcpy(&msg->port.data[i], port->lun_map,
                    msg->port.lun_map_len);
                i += msg->port.lun_map_len;
        }
        if (port->port_devid) {
                msg->port.port_devid_len = port->port_devid->len;
                memcpy(&msg->port.data[i], port->port_devid->data,
                    msg->port.port_devid_len);
                i += msg->port.port_devid_len;
        }
        if (port->target_devid) {
                msg->port.target_devid_len = port->target_devid->len;
                memcpy(&msg->port.data[i], port->target_devid->data,
                    msg->port.target_devid_len);
                i += msg->port.target_devid_len;
        }
        if (port->init_devid) {
                msg->port.init_devid_len = port->init_devid->len;
                memcpy(&msg->port.data[i], port->init_devid->data,
                    msg->port.init_devid_len);
                i += msg->port.init_devid_len;
        }
        ctl_ha_msg_send(CTL_HA_CHAN_CTL, &msg->port, sizeof(msg->port) + i,
            M_WAITOK);
        free(msg, M_CTL);
}

void
ctl_isc_announce_iid(struct ctl_port *port, int iid)
{
        struct ctl_softc *softc = port->ctl_softc;
        union ctl_ha_msg *msg;
        int i, l;

        if (port->targ_port < softc->port_min ||
            port->targ_port >= softc->port_max ||
            softc->ha_link != CTL_HA_LINK_ONLINE)
                return;
        mtx_lock(&softc->ctl_lock);
        i = sizeof(msg->iid);
        l = 0;
        if (port->wwpn_iid[iid].name)
                l = strlen(port->wwpn_iid[iid].name) + 1;
        i += l;
        msg = malloc(i, M_CTL, M_NOWAIT);
        if (msg == NULL) {
                mtx_unlock(&softc->ctl_lock);
                return;
        }
        bzero(&msg->iid, sizeof(msg->iid));
        msg->hdr.msg_type = CTL_MSG_IID_SYNC;
        msg->hdr.nexus.targ_port = port->targ_port;
        msg->hdr.nexus.initid = iid;
        msg->iid.in_use = port->wwpn_iid[iid].in_use;
        msg->iid.name_len = l;
        msg->iid.wwpn = port->wwpn_iid[iid].wwpn;
        if (port->wwpn_iid[iid].name)
                strlcpy(msg->iid.data, port->wwpn_iid[iid].name, l);
        mtx_unlock(&softc->ctl_lock);
        ctl_ha_msg_send(CTL_HA_CHAN_CTL, &msg->iid, i, M_NOWAIT);
        free(msg, M_CTL);
}

void
ctl_isc_announce_mode(struct ctl_lun *lun, uint32_t initidx,
    uint8_t page, uint8_t subpage)
{
        struct ctl_softc *softc = lun->ctl_softc;
        union ctl_ha_msg msg;
        u_int i;

        if (softc->ha_link != CTL_HA_LINK_ONLINE)
                return;
        for (i = 0; i < CTL_NUM_MODE_PAGES; i++) {
                if ((lun->mode_pages.index[i].page_code & SMPH_PC_MASK) ==
                    page && lun->mode_pages.index[i].subpage == subpage)
                        break;
        }
        if (i == CTL_NUM_MODE_PAGES)
                return;

        /* Don't try to replicate pages not present on this device. */
        if (lun->mode_pages.index[i].page_data == NULL)
                return;

        bzero(&msg.mode, sizeof(msg.mode));
        msg.hdr.msg_type = CTL_MSG_MODE_SYNC;
        msg.hdr.nexus.targ_port = initidx / CTL_MAX_INIT_PER_PORT;
        msg.hdr.nexus.initid = initidx % CTL_MAX_INIT_PER_PORT;
        msg.hdr.nexus.targ_lun = lun->lun;
        msg.hdr.nexus.targ_mapped_lun = lun->lun;
        msg.mode.page_code = page;
        msg.mode.subpage = subpage;
        msg.mode.page_len = lun->mode_pages.index[i].page_len;
        memcpy(msg.mode.data, lun->mode_pages.index[i].page_data,
            msg.mode.page_len);
        ctl_ha_msg_send(CTL_HA_CHAN_CTL, &msg.mode, sizeof(msg.mode),
            M_WAITOK);
}

static void
ctl_isc_ha_link_up(struct ctl_softc *softc)
{
        struct ctl_port *port;
        struct ctl_lun *lun;
        union ctl_ha_msg msg;
        int i;

        /* Announce this node parameters to peer for validation. */
        msg.login.msg_type = CTL_MSG_LOGIN;
        msg.login.version = CTL_HA_VERSION;
        msg.login.ha_mode = softc->ha_mode;
        msg.login.ha_id = softc->ha_id;
        msg.login.max_luns = ctl_max_luns;
        msg.login.max_ports = ctl_max_ports;
        msg.login.max_init_per_port = CTL_MAX_INIT_PER_PORT;
        ctl_ha_msg_send(CTL_HA_CHAN_CTL, &msg.login, sizeof(msg.login),
            M_WAITOK);

        STAILQ_FOREACH(port, &softc->port_list, links) {
                ctl_isc_announce_port(port);
                for (i = 0; i < CTL_MAX_INIT_PER_PORT; i++) {
                        if (port->wwpn_iid[i].in_use)
                                ctl_isc_announce_iid(port, i);
                }
        }
        STAILQ_FOREACH(lun, &softc->lun_list, links)
                ctl_isc_announce_lun(lun);
}

static void
ctl_isc_ha_link_down(struct ctl_softc *softc)
{
        struct ctl_port *port;
        struct ctl_lun *lun;
        union ctl_io *io;
        int i;

        mtx_lock(&softc->ctl_lock);
        STAILQ_FOREACH(lun, &softc->lun_list, links) {
                mtx_lock(&lun->lun_lock);
                if (lun->flags & CTL_LUN_PEER_SC_PRIMARY) {
                        lun->flags &= ~CTL_LUN_PEER_SC_PRIMARY;
                        ctl_est_ua_all(lun, -1, CTL_UA_ASYM_ACC_CHANGE);
                }
                mtx_unlock(&lun->lun_lock);

                mtx_unlock(&softc->ctl_lock);
                io = ctl_alloc_io(softc->othersc_pool);
                mtx_lock(&softc->ctl_lock);
                ctl_zero_io(io);
                io->io_hdr.msg_type = CTL_MSG_FAILOVER;
                io->io_hdr.nexus.targ_mapped_lun = lun->lun;
                ctl_enqueue_isc(io);
        }

        STAILQ_FOREACH(port, &softc->port_list, links) {
                if (port->targ_port >= softc->port_min &&
                    port->targ_port < softc->port_max)
                        continue;
                port->status &= ~CTL_PORT_STATUS_ONLINE;
                for (i = 0; i < CTL_MAX_INIT_PER_PORT; i++) {
                        port->wwpn_iid[i].in_use = 0;
                        free(port->wwpn_iid[i].name, M_CTL);
                        port->wwpn_iid[i].name = NULL;
                }
        }
        mtx_unlock(&softc->ctl_lock);
}

static void
ctl_isc_ua(struct ctl_softc *softc, union ctl_ha_msg *msg, int len)
{
        struct ctl_lun *lun;
        uint32_t iid = ctl_get_initindex(&msg->hdr.nexus);

        mtx_lock(&softc->ctl_lock);
        if (msg->hdr.nexus.targ_mapped_lun >= ctl_max_luns ||
            (lun = softc->ctl_luns[msg->hdr.nexus.targ_mapped_lun]) == NULL) {
                mtx_unlock(&softc->ctl_lock);
                return;
        }
        mtx_lock(&lun->lun_lock);
        mtx_unlock(&softc->ctl_lock);
        if (msg->ua.ua_type == CTL_UA_THIN_PROV_THRES && msg->ua.ua_set)
                memcpy(lun->ua_tpt_info, msg->ua.ua_info, 8);
        if (msg->ua.ua_all) {
                if (msg->ua.ua_set)
                        ctl_est_ua_all(lun, iid, msg->ua.ua_type);
                else
                        ctl_clr_ua_all(lun, iid, msg->ua.ua_type);
        } else {
                if (msg->ua.ua_set)
                        ctl_est_ua(lun, iid, msg->ua.ua_type);
                else
                        ctl_clr_ua(lun, iid, msg->ua.ua_type);
        }
        mtx_unlock(&lun->lun_lock);
}

static void
ctl_isc_lun_sync(struct ctl_softc *softc, union ctl_ha_msg *msg, int len)
{
        struct ctl_lun *lun;
        struct ctl_ha_msg_lun_pr_key pr_key;
        int i, k;
        ctl_lun_flags oflags;
        uint32_t targ_lun;

        targ_lun = msg->hdr.nexus.targ_mapped_lun;
        mtx_lock(&softc->ctl_lock);
        if (targ_lun >= ctl_max_luns ||
            (lun = softc->ctl_luns[targ_lun]) == NULL) {
                mtx_unlock(&softc->ctl_lock);
                return;
        }
        mtx_lock(&lun->lun_lock);
        mtx_unlock(&softc->ctl_lock);
        if (lun->flags & CTL_LUN_DISABLED) {
                mtx_unlock(&lun->lun_lock);
                return;
        }
        i = (lun->lun_devid != NULL) ? lun->lun_devid->len : 0;
        if (msg->lun.lun_devid_len != i || (i > 0 &&
            memcmp(&msg->lun.data[0], lun->lun_devid->data, i) != 0)) {
                mtx_unlock(&lun->lun_lock);
                printf("%s: Received conflicting HA LUN %d\n",
                    __func__, targ_lun);
                return;
        } else {
                /* Record whether peer is primary. */
                oflags = lun->flags;
                if ((msg->lun.flags & CTL_LUN_PRIMARY_SC) &&
                    (msg->lun.flags & CTL_LUN_DISABLED) == 0)
                        lun->flags |= CTL_LUN_PEER_SC_PRIMARY;
                else
                        lun->flags &= ~CTL_LUN_PEER_SC_PRIMARY;
                if (oflags != lun->flags)
                        ctl_est_ua_all(lun, -1, CTL_UA_ASYM_ACC_CHANGE);

                /* If peer is primary and we are not -- use data */
                if ((lun->flags & CTL_LUN_PRIMARY_SC) == 0 &&
                    (lun->flags & CTL_LUN_PEER_SC_PRIMARY)) {
                        lun->pr_generation = msg->lun.pr_generation;
                        lun->pr_res_idx = msg->lun.pr_res_idx;
                        lun->pr_res_type = msg->lun.pr_res_type;
                        lun->pr_key_count = msg->lun.pr_key_count;
                        for (k = 0; k < CTL_MAX_INITIATORS; k++)
                                ctl_clr_prkey(lun, k);
                        for (k = 0; k < msg->lun.pr_key_count; k++) {
                                memcpy(&pr_key, &msg->lun.data[i],
                                    sizeof(pr_key));
                                ctl_alloc_prkey(lun, pr_key.pr_iid);
                                ctl_set_prkey(lun, pr_key.pr_iid,
                                    pr_key.pr_key);
                                i += sizeof(pr_key);
                        }
                }

                mtx_unlock(&lun->lun_lock);
                CTL_DEBUG_PRINT(("%s: Known LUN %d, peer is %s\n",
                    __func__, targ_lun,
                    (msg->lun.flags & CTL_LUN_PRIMARY_SC) ?
                    "primary" : "secondary"));

                /* If we are primary but peer doesn't know -- notify */
                if ((lun->flags & CTL_LUN_PRIMARY_SC) &&
                    (msg->lun.flags & CTL_LUN_PEER_SC_PRIMARY) == 0)
                        ctl_isc_announce_lun(lun);
        }
}

static void
ctl_isc_port_sync(struct ctl_softc *softc, union ctl_ha_msg *msg, int len)
{
        struct ctl_port *port;
        struct ctl_lun *lun;
        int i, new;

        port = softc->ctl_ports[msg->hdr.nexus.targ_port];
        if (port == NULL) {
                CTL_DEBUG_PRINT(("%s: New port %d\n", __func__,
                    msg->hdr.nexus.targ_port));
                new = 1;
                port = malloc(sizeof(*port), M_CTL, M_WAITOK | M_ZERO);
                port->frontend = &ha_frontend;
                port->targ_port = msg->hdr.nexus.targ_port;
                port->fe_datamove = ctl_ha_datamove;
                port->fe_done = ctl_ha_done;
        } else if (port->frontend == &ha_frontend) {
                CTL_DEBUG_PRINT(("%s: Updated port %d\n", __func__,
                    msg->hdr.nexus.targ_port));
                new = 0;
        } else {
                printf("%s: Received conflicting HA port %d\n",
                    __func__, msg->hdr.nexus.targ_port);
                return;
        }
        port->port_type = msg->port.port_type;
        port->physical_port = msg->port.physical_port;
        port->virtual_port = msg->port.virtual_port;
        port->status = msg->port.status;
        i = 0;
        free(port->port_name, M_CTL);
        port->port_name = strndup(&msg->port.data[i], msg->port.name_len,
            M_CTL);
        i += msg->port.name_len;
        if (msg->port.lun_map_len != 0) {
                if (port->lun_map == NULL ||
                    port->lun_map_size * sizeof(uint32_t) <
                    msg->port.lun_map_len) {
                        port->lun_map_size = 0;
                        free(port->lun_map, M_CTL);
                        port->lun_map = malloc(msg->port.lun_map_len,
                            M_CTL, M_WAITOK);
                }
                memcpy(port->lun_map, &msg->port.data[i], msg->port.lun_map_len);
                port->lun_map_size = msg->port.lun_map_len / sizeof(uint32_t);
                i += msg->port.lun_map_len;
        } else {
                port->lun_map_size = 0;
                free(port->lun_map, M_CTL);
                port->lun_map = NULL;
        }
        if (msg->port.port_devid_len != 0) {
                if (port->port_devid == NULL ||
                    port->port_devid->len < msg->port.port_devid_len) {
                        free(port->port_devid, M_CTL);
                        port->port_devid = malloc(sizeof(struct ctl_devid) +
                            msg->port.port_devid_len, M_CTL, M_WAITOK);
                }
                memcpy(port->port_devid->data, &msg->port.data[i],
                    msg->port.port_devid_len);
                port->port_devid->len = msg->port.port_devid_len;
                i += msg->port.port_devid_len;
        } else {
                free(port->port_devid, M_CTL);
                port->port_devid = NULL;
        }
        if (msg->port.target_devid_len != 0) {
                if (port->target_devid == NULL ||
                    port->target_devid->len < msg->port.target_devid_len) {
                        free(port->target_devid, M_CTL);
                        port->target_devid = malloc(sizeof(struct ctl_devid) +
                            msg->port.target_devid_len, M_CTL, M_WAITOK);
                }
                memcpy(port->target_devid->data, &msg->port.data[i],
                    msg->port.target_devid_len);
                port->target_devid->len = msg->port.target_devid_len;
                i += msg->port.target_devid_len;
        } else {
                free(port->target_devid, M_CTL);
                port->target_devid = NULL;
        }
        if (msg->port.init_devid_len != 0) {
                if (port->init_devid == NULL ||
                    port->init_devid->len < msg->port.init_devid_len) {
                        free(port->init_devid, M_CTL);
                        port->init_devid = malloc(sizeof(struct ctl_devid) +
                            msg->port.init_devid_len, M_CTL, M_WAITOK);
                }
                memcpy(port->init_devid->data, &msg->port.data[i],
                    msg->port.init_devid_len);
                port->init_devid->len = msg->port.init_devid_len;
                i += msg->port.init_devid_len;
        } else {
                free(port->init_devid, M_CTL);
                port->init_devid = NULL;
        }
        if (new) {
                if (ctl_port_register(port) != 0) {
                        printf("%s: ctl_port_register() failed with error\n",
                            __func__);
                }
        }
        mtx_lock(&softc->ctl_lock);
        STAILQ_FOREACH(lun, &softc->lun_list, links) {
                if (ctl_lun_map_to_port(port, lun->lun) == UINT32_MAX)
                        continue;
                mtx_lock(&lun->lun_lock);
                ctl_est_ua_all(lun, -1, CTL_UA_INQ_CHANGE);
                mtx_unlock(&lun->lun_lock);
        }
        mtx_unlock(&softc->ctl_lock);
}

static void
ctl_isc_iid_sync(struct ctl_softc *softc, union ctl_ha_msg *msg, int len)
{
        struct ctl_port *port;
        int iid;

        port = softc->ctl_ports[msg->hdr.nexus.targ_port];
        if (port == NULL) {
                printf("%s: Received IID for unknown port %d\n",
                    __func__, msg->hdr.nexus.targ_port);
                return;
        }
        iid = msg->hdr.nexus.initid;
        if (port->wwpn_iid[iid].in_use != 0 &&
            msg->iid.in_use == 0)
                ctl_i_t_nexus_loss(softc, iid, CTL_UA_POWERON);
        port->wwpn_iid[iid].in_use = msg->iid.in_use;
        port->wwpn_iid[iid].wwpn = msg->iid.wwpn;
        free(port->wwpn_iid[iid].name, M_CTL);
        if (msg->iid.name_len) {
                port->wwpn_iid[iid].name = strndup(&msg->iid.data[0],
                    msg->iid.name_len, M_CTL);
        } else
                port->wwpn_iid[iid].name = NULL;
}

static void
ctl_isc_login(struct ctl_softc *softc, union ctl_ha_msg *msg, int len)
{

        if (msg->login.version != CTL_HA_VERSION) {
                printf("CTL HA peers have different versions %d != %d\n",
                    msg->login.version, CTL_HA_VERSION);
                ctl_ha_msg_abort(CTL_HA_CHAN_CTL);
                return;
        }
        if (msg->login.ha_mode != softc->ha_mode) {
                printf("CTL HA peers have different ha_mode %d != %d\n",
                    msg->login.ha_mode, softc->ha_mode);
                ctl_ha_msg_abort(CTL_HA_CHAN_CTL);
                return;
        }
        if (msg->login.ha_id == softc->ha_id) {
                printf("CTL HA peers have same ha_id %d\n", msg->login.ha_id);
                ctl_ha_msg_abort(CTL_HA_CHAN_CTL);
                return;
        }
        if (msg->login.max_luns != ctl_max_luns ||
            msg->login.max_ports != ctl_max_ports ||
            msg->login.max_init_per_port != CTL_MAX_INIT_PER_PORT) {
                printf("CTL HA peers have different limits\n");
                ctl_ha_msg_abort(CTL_HA_CHAN_CTL);
                return;
        }
}

static void
ctl_isc_mode_sync(struct ctl_softc *softc, union ctl_ha_msg *msg, int len)
{
        struct ctl_lun *lun;
        u_int i;
        uint32_t initidx, targ_lun;

        targ_lun = msg->hdr.nexus.targ_mapped_lun;
        mtx_lock(&softc->ctl_lock);
        if (targ_lun >= ctl_max_luns ||
            (lun = softc->ctl_luns[targ_lun]) == NULL) {
                mtx_unlock(&softc->ctl_lock);
                return;
        }
        mtx_lock(&lun->lun_lock);
        mtx_unlock(&softc->ctl_lock);
        if (lun->flags & CTL_LUN_DISABLED) {
                mtx_unlock(&lun->lun_lock);
                return;
        }
        for (i = 0; i < CTL_NUM_MODE_PAGES; i++) {
                if ((lun->mode_pages.index[i].page_code & SMPH_PC_MASK) ==
                    msg->mode.page_code &&
                    lun->mode_pages.index[i].subpage == msg->mode.subpage)
                        break;
        }
        if (i == CTL_NUM_MODE_PAGES) {
                mtx_unlock(&lun->lun_lock);
                return;
        }
        memcpy(lun->mode_pages.index[i].page_data, msg->mode.data,
            lun->mode_pages.index[i].page_len);
        initidx = ctl_get_initindex(&msg->hdr.nexus);
        if (initidx != -1)
                ctl_est_ua_all(lun, initidx, CTL_UA_MODE_CHANGE);
        mtx_unlock(&lun->lun_lock);
}

/*
 * ISC (Inter Shelf Communication) event handler.  Events from the HA
 * subsystem come in here.
 */
static void
ctl_isc_event_handler(ctl_ha_channel channel, ctl_ha_event event, int param)
{
        struct ctl_softc *softc = control_softc;
        union ctl_io *io;
        struct ctl_prio *presio;
        ctl_ha_status isc_status;

        CTL_DEBUG_PRINT(("CTL: Isc Msg event %d\n", event));
        if (event == CTL_HA_EVT_MSG_RECV) {
                union ctl_ha_msg *msg, msgbuf;

                if (param > sizeof(msgbuf))
                        msg = malloc(param, M_CTL, M_WAITOK);
                else
                        msg = &msgbuf;
                isc_status = ctl_ha_msg_recv(CTL_HA_CHAN_CTL, msg, param,
                    M_WAITOK);
                if (isc_status != CTL_HA_STATUS_SUCCESS) {
                        printf("%s: Error receiving message: %d\n",
                            __func__, isc_status);
                        if (msg != &msgbuf)
                                free(msg, M_CTL);
                        return;
                }

                CTL_DEBUG_PRINT(("CTL: msg_type %d\n", msg->hdr.msg_type));
                switch (msg->hdr.msg_type) {
                case CTL_MSG_SERIALIZE:
                        io = ctl_alloc_io(softc->othersc_pool);
                        ctl_zero_io(io);
                        // populate ctsio from msg
                        io->io_hdr.io_type = CTL_IO_SCSI;
                        io->io_hdr.msg_type = CTL_MSG_SERIALIZE;
                        io->io_hdr.remote_io = msg->hdr.original_sc;
                        io->io_hdr.flags |= CTL_FLAG_FROM_OTHER_SC |
                                            CTL_FLAG_IO_ACTIVE;
                        /*
                         * If we're in serialization-only mode, we don't
                         * want to go through full done processing.  Thus
                         * the COPY flag.
                         *
                         * XXX KDM add another flag that is more specific.
                         */
                        if (softc->ha_mode != CTL_HA_MODE_XFER)
                                io->io_hdr.flags |= CTL_FLAG_INT_COPY;
                        io->io_hdr.nexus = msg->hdr.nexus;
                        io->scsiio.tag_num = msg->scsi.tag_num;
                        io->scsiio.tag_type = msg->scsi.tag_type;
#ifdef CTL_TIME_IO
                        io->io_hdr.start_time = time_uptime;
                        getbinuptime(&io->io_hdr.start_bt);
#endif /* CTL_TIME_IO */
                        io->scsiio.cdb_len = msg->scsi.cdb_len;
                        memcpy(io->scsiio.cdb, msg->scsi.cdb,
                               CTL_MAX_CDBLEN);
                        if (softc->ha_mode == CTL_HA_MODE_XFER) {
                                const struct ctl_cmd_entry *entry;

                                entry = ctl_get_cmd_entry(&io->scsiio, NULL);
                                io->io_hdr.flags &= ~CTL_FLAG_DATA_MASK;
                                io->io_hdr.flags |=
                                        entry->flags & CTL_FLAG_DATA_MASK;
                        }
                        ctl_enqueue_isc(io);
                        break;

                /* Performed on the Originating SC, XFER mode only */
                case CTL_MSG_DATAMOVE: {
                        struct ctl_sg_entry *sgl;
                        int i, j;

                        io = msg->hdr.original_sc;
                        if (io == NULL) {
                                printf("%s: original_sc == NULL!\n", __func__);
                                /* XXX KDM do something here */
                                break;
                        }
                        io->io_hdr.msg_type = CTL_MSG_DATAMOVE;
                        io->io_hdr.flags |= CTL_FLAG_IO_ACTIVE;
                        /*
                         * Keep track of this, we need to send it back over
                         * when the datamove is complete.
                         */
                        io->io_hdr.remote_io = msg->hdr.serializing_sc;
                        if (msg->hdr.status == CTL_SUCCESS)
                                io->io_hdr.status = msg->hdr.status;

                        if (msg->dt.sg_sequence == 0) {
#ifdef CTL_TIME_IO
                                getbinuptime(&io->io_hdr.dma_start_bt);
#endif
                                i = msg->dt.kern_sg_entries +
                                    msg->dt.kern_data_len /
                                    CTL_HA_DATAMOVE_SEGMENT + 1;
                                sgl = malloc(sizeof(*sgl) * i, M_CTL,
                                    M_WAITOK | M_ZERO);
                                CTL_RSGL(io) = sgl;
                                CTL_LSGL(io) = &sgl[msg->dt.kern_sg_entries];

                                io->scsiio.kern_data_ptr = (uint8_t *)sgl;

                                io->scsiio.kern_sg_entries =
                                        msg->dt.kern_sg_entries;
                                io->scsiio.rem_sg_entries =
                                        msg->dt.kern_sg_entries;
                                io->scsiio.kern_data_len =
                                        msg->dt.kern_data_len;
                                io->scsiio.kern_total_len =
                                        msg->dt.kern_total_len;
                                io->scsiio.kern_data_resid =
                                        msg->dt.kern_data_resid;
                                io->scsiio.kern_rel_offset =
                                        msg->dt.kern_rel_offset;
                                io->io_hdr.flags &= ~CTL_FLAG_BUS_ADDR;
                                io->io_hdr.flags |= msg->dt.flags &
                                    CTL_FLAG_BUS_ADDR;
                        } else
                                sgl = (struct ctl_sg_entry *)
                                        io->scsiio.kern_data_ptr;

                        for (i = msg->dt.sent_sg_entries, j = 0;
                             i < (msg->dt.sent_sg_entries +
                             msg->dt.cur_sg_entries); i++, j++) {
                                sgl[i].addr = msg->dt.sg_list[j].addr;
                                sgl[i].len = msg->dt.sg_list[j].len;
                        }

                        /*
                         * If this is the last piece of the I/O, we've got
                         * the full S/G list.  Queue processing in the thread.
                         * Otherwise wait for the next piece.
                         */
                        if (msg->dt.sg_last != 0)
                                ctl_enqueue_isc(io);
                        break;
                }
                /* Performed on the Serializing (primary) SC, XFER mode only */
                case CTL_MSG_DATAMOVE_DONE: {
                        if (msg->hdr.serializing_sc == NULL) {
                                printf("%s: serializing_sc == NULL!\n",
                                       __func__);
                                /* XXX KDM now what? */
                                break;
                        }
                        /*
                         * We grab the sense information here in case
                         * there was a failure, so we can return status
                         * back to the initiator.
                         */
                        io = msg->hdr.serializing_sc;
                        io->io_hdr.msg_type = CTL_MSG_DATAMOVE_DONE;
                        io->io_hdr.flags &= ~CTL_FLAG_DMA_INPROG;
                        io->io_hdr.flags |= CTL_FLAG_IO_ACTIVE;
                        io->io_hdr.port_status = msg->scsi.port_status;
                        io->scsiio.kern_data_resid = msg->scsi.kern_data_resid;
                        if (msg->hdr.status != CTL_STATUS_NONE) {
                                io->io_hdr.status = msg->hdr.status;
                                io->scsiio.scsi_status = msg->scsi.scsi_status;
                                io->scsiio.sense_len = msg->scsi.sense_len;
                                memcpy(&io->scsiio.sense_data,
                                    &msg->scsi.sense_data,
                                    msg->scsi.sense_len);
                                if (msg->hdr.status == CTL_SUCCESS)
                                        io->io_hdr.flags |= CTL_FLAG_STATUS_SENT;
                        }
                        ctl_enqueue_isc(io);
                        break;
                }

                /* Preformed on Originating SC, SER_ONLY mode */
                case CTL_MSG_R2R:
                        io = msg->hdr.original_sc;
                        if (io == NULL) {
                                printf("%s: original_sc == NULL!\n",
                                    __func__);
                                break;
                        }
                        io->io_hdr.flags |= CTL_FLAG_IO_ACTIVE;
                        io->io_hdr.msg_type = CTL_MSG_R2R;
                        io->io_hdr.remote_io = msg->hdr.serializing_sc;
                        ctl_enqueue_isc(io);
                        break;

                /*
                 * Performed on Serializing(i.e. primary SC) SC in SER_ONLY
                 * mode.
                 * Performed on the Originating (i.e. secondary) SC in XFER
                 * mode
                 */
                case CTL_MSG_FINISH_IO:
                        if (softc->ha_mode == CTL_HA_MODE_XFER)
                                ctl_isc_handler_finish_xfer(softc, msg);
                        else
                                ctl_isc_handler_finish_ser_only(softc, msg);
                        break;

                /* Preformed on Originating SC */
                case CTL_MSG_BAD_JUJU:
                        io = msg->hdr.original_sc;
                        if (io == NULL) {
                                printf("%s: Bad JUJU!, original_sc is NULL!\n",
                                       __func__);
                                break;
                        }
                        ctl_copy_sense_data(msg, io);
                        /*
                         * IO should have already been cleaned up on other
                         * SC so clear this flag so we won't send a message
                         * back to finish the IO there.
                         */
                        io->io_hdr.flags &= ~CTL_FLAG_SENT_2OTHER_SC;
                        io->io_hdr.flags |= CTL_FLAG_IO_ACTIVE;

                        /* io = msg->hdr.serializing_sc; */
                        io->io_hdr.msg_type = CTL_MSG_BAD_JUJU;
                        ctl_enqueue_isc(io);
                        break;

                /* Handle resets sent from the other side */
                case CTL_MSG_MANAGE_TASKS: {
                        struct ctl_taskio *taskio;
                        taskio = (struct ctl_taskio *)ctl_alloc_io(
                            softc->othersc_pool);
                        ctl_zero_io((union ctl_io *)taskio);
                        taskio->io_hdr.io_type = CTL_IO_TASK;
                        taskio->io_hdr.flags |= CTL_FLAG_FROM_OTHER_SC;
                        taskio->io_hdr.nexus = msg->hdr.nexus;
                        taskio->task_action = msg->task.task_action;
                        taskio->tag_num = msg->task.tag_num;
                        taskio->tag_type = msg->task.tag_type;
#ifdef CTL_TIME_IO
                        taskio->io_hdr.start_time = time_uptime;
                        getbinuptime(&taskio->io_hdr.start_bt);
#endif /* CTL_TIME_IO */
                        ctl_run_task((union ctl_io *)taskio);
                        break;
                }
                /* Persistent Reserve action which needs attention */
                case CTL_MSG_PERS_ACTION:
                        presio = (struct ctl_prio *)ctl_alloc_io(
                            softc->othersc_pool);
                        ctl_zero_io((union ctl_io *)presio);
                        presio->io_hdr.msg_type = CTL_MSG_PERS_ACTION;
                        presio->io_hdr.flags |= CTL_FLAG_FROM_OTHER_SC;
                        presio->io_hdr.nexus = msg->hdr.nexus;
                        presio->pr_msg = msg->pr;
                        ctl_enqueue_isc((union ctl_io *)presio);
                        break;
                case CTL_MSG_UA:
                        ctl_isc_ua(softc, msg, param);
                        break;
                case CTL_MSG_PORT_SYNC:
                        ctl_isc_port_sync(softc, msg, param);
                        break;
                case CTL_MSG_LUN_SYNC:
                        ctl_isc_lun_sync(softc, msg, param);
                        break;
                case CTL_MSG_IID_SYNC:
                        ctl_isc_iid_sync(softc, msg, param);
                        break;
                case CTL_MSG_LOGIN:
                        ctl_isc_login(softc, msg, param);
                        break;
                case CTL_MSG_MODE_SYNC:
                        ctl_isc_mode_sync(softc, msg, param);
                        break;
                default:
                        printf("Received HA message of unknown type %d\n",
                            msg->hdr.msg_type);
                        ctl_ha_msg_abort(CTL_HA_CHAN_CTL);
                        break;
                }
                if (msg != &msgbuf)
                        free(msg, M_CTL);
        } else if (event == CTL_HA_EVT_LINK_CHANGE) {
                printf("CTL: HA link status changed from %d to %d\n",
                    softc->ha_link, param);
                if (param == softc->ha_link)
                        return;
                if (softc->ha_link == CTL_HA_LINK_ONLINE) {
                        softc->ha_link = param;
                        ctl_isc_ha_link_down(softc);
                } else {
                        softc->ha_link = param;
                        if (softc->ha_link == CTL_HA_LINK_ONLINE)
                                ctl_isc_ha_link_up(softc);
                }
                return;
        } else {
                printf("ctl_isc_event_handler: Unknown event %d\n", event);
                return;
        }
}

static void
ctl_copy_sense_data(union ctl_ha_msg *src, union ctl_io *dest)
{

        memcpy(&dest->scsiio.sense_data, &src->scsi.sense_data,
            src->scsi.sense_len);
        dest->scsiio.scsi_status = src->scsi.scsi_status;
        dest->scsiio.sense_len = src->scsi.sense_len;
        dest->io_hdr.status = src->hdr.status;
}

static void
ctl_copy_sense_data_back(union ctl_io *src, union ctl_ha_msg *dest)
{

        memcpy(&dest->scsi.sense_data, &src->scsiio.sense_data,
            src->scsiio.sense_len);
        dest->scsi.scsi_status = src->scsiio.scsi_status;
        dest->scsi.sense_len = src->scsiio.sense_len;
        dest->hdr.status = src->io_hdr.status;
}

void
ctl_est_ua(struct ctl_lun *lun, uint32_t initidx, ctl_ua_type ua)
{
        struct ctl_softc *softc = lun->ctl_softc;
        ctl_ua_type *pu;

        if (initidx < softc->init_min || initidx >= softc->init_max)
                return;
        mtx_assert(&lun->lun_lock, MA_OWNED);
        pu = lun->pending_ua[initidx / CTL_MAX_INIT_PER_PORT];
        if (pu == NULL)
                return;
        pu[initidx % CTL_MAX_INIT_PER_PORT] |= ua;
}

void
ctl_est_ua_port(struct ctl_lun *lun, int port, uint32_t except, ctl_ua_type ua)
{
        int i;

        mtx_assert(&lun->lun_lock, MA_OWNED);
        if (lun->pending_ua[port] == NULL)
                return;
        for (i = 0; i < CTL_MAX_INIT_PER_PORT; i++) {
                if (port * CTL_MAX_INIT_PER_PORT + i == except)
                        continue;
                lun->pending_ua[port][i] |= ua;
        }
}

void
ctl_est_ua_all(struct ctl_lun *lun, uint32_t except, ctl_ua_type ua)
{
        struct ctl_softc *softc = lun->ctl_softc;
        int i;

        mtx_assert(&lun->lun_lock, MA_OWNED);
        for (i = softc->port_min; i < softc->port_max; i++)
                ctl_est_ua_port(lun, i, except, ua);
}

void
ctl_clr_ua(struct ctl_lun *lun, uint32_t initidx, ctl_ua_type ua)
{
        struct ctl_softc *softc = lun->ctl_softc;
        ctl_ua_type *pu;

        if (initidx < softc->init_min || initidx >= softc->init_max)
                return;
        mtx_assert(&lun->lun_lock, MA_OWNED);
        pu = lun->pending_ua[initidx / CTL_MAX_INIT_PER_PORT];
        if (pu == NULL)
                return;
        pu[initidx % CTL_MAX_INIT_PER_PORT] &= ~ua;
}

void
ctl_clr_ua_all(struct ctl_lun *lun, uint32_t except, ctl_ua_type ua)
{
        struct ctl_softc *softc = lun->ctl_softc;
        int i, j;

        mtx_assert(&lun->lun_lock, MA_OWNED);
        for (i = softc->port_min; i < softc->port_max; i++) {
                if (lun->pending_ua[i] == NULL)
                        continue;
                for (j = 0; j < CTL_MAX_INIT_PER_PORT; j++) {
                        if (i * CTL_MAX_INIT_PER_PORT + j == except)
                                continue;
                        lun->pending_ua[i][j] &= ~ua;
                }
        }
}

void
ctl_clr_ua_allluns(struct ctl_softc *ctl_softc, uint32_t initidx,
    ctl_ua_type ua_type)
{
        struct ctl_lun *lun;

        mtx_assert(&ctl_softc->ctl_lock, MA_OWNED);
        STAILQ_FOREACH(lun, &ctl_softc->lun_list, links) {
                mtx_lock(&lun->lun_lock);
                ctl_clr_ua(lun, initidx, ua_type);
                mtx_unlock(&lun->lun_lock);
        }
}

static int
ctl_ha_role_sysctl(SYSCTL_HANDLER_ARGS)
{
        struct ctl_softc *softc = (struct ctl_softc *)arg1;
        struct ctl_lun *lun;
        struct ctl_lun_req ireq;
        int error, value;

        value = (softc->flags & CTL_FLAG_ACTIVE_SHELF) ? 0 : 1;
        error = sysctl_handle_int(oidp, &value, 0, req);
        if ((error != 0) || (req->newptr == NULL))
                return (error);

        mtx_lock(&softc->ctl_lock);
        if (value == 0)
                softc->flags |= CTL_FLAG_ACTIVE_SHELF;
        else
                softc->flags &= ~CTL_FLAG_ACTIVE_SHELF;
        STAILQ_FOREACH(lun, &softc->lun_list, links) {
                mtx_unlock(&softc->ctl_lock);
                bzero(&ireq, sizeof(ireq));
                ireq.reqtype = CTL_LUNREQ_MODIFY;
                ireq.reqdata.modify.lun_id = lun->lun;
                lun->backend->ioctl(NULL, CTL_LUN_REQ, (caddr_t)&ireq, 0,
                    curthread);
                if (ireq.status != CTL_LUN_OK) {
                        printf("%s: CTL_LUNREQ_MODIFY returned %d '%s'\n",
                            __func__, ireq.status, ireq.error_str);
                }
                mtx_lock(&softc->ctl_lock);
        }
        mtx_unlock(&softc->ctl_lock);
        return (0);
}

static int
ctl_init(void)
{
        struct make_dev_args args;
        struct ctl_softc *softc;
        int i, error;

        softc = control_softc = malloc(sizeof(*control_softc), M_DEVBUF,
                               M_WAITOK | M_ZERO);

        make_dev_args_init(&args);
        args.mda_devsw = &ctl_cdevsw;
        args.mda_uid = UID_ROOT;
        args.mda_gid = GID_OPERATOR;
        args.mda_mode = 0600;
        args.mda_si_drv1 = softc;
        args.mda_si_drv2 = NULL;
        error = make_dev_s(&args, &softc->dev, "cam/ctl");
        if (error != 0) {
                free(softc, M_DEVBUF);
                control_softc = NULL;
                return (error);
        }

        sysctl_ctx_init(&softc->sysctl_ctx);
        softc->sysctl_tree = SYSCTL_ADD_NODE(&softc->sysctl_ctx,
                SYSCTL_STATIC_CHILDREN(_kern_cam), OID_AUTO, "ctl",
                CTLFLAG_RD | CTLFLAG_MPSAFE, 0, "CAM Target Layer");

        if (softc->sysctl_tree == NULL) {
                printf("%s: unable to allocate sysctl tree\n", __func__);
                destroy_dev(softc->dev);
                free(softc, M_DEVBUF);
                control_softc = NULL;
                return (ENOMEM);
        }

        mtx_init(&softc->ctl_lock, "CTL mutex", NULL, MTX_DEF);
        softc->io_zone = uma_zcreate("CTL IO", sizeof(union ctl_io),
            NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
        softc->flags = 0;

        SYSCTL_ADD_INT(&softc->sysctl_ctx, SYSCTL_CHILDREN(softc->sysctl_tree),
            OID_AUTO, "ha_mode", CTLFLAG_RDTUN, (int *)&softc->ha_mode, 0,
            "HA mode (0 - act/stby, 1 - serialize only, 2 - xfer)");

        if (ctl_max_luns <= 0 || powerof2(ctl_max_luns) == 0) {
                printf("Bad value %d for kern.cam.ctl.max_luns, must be a power of two, using %d\n",
                    ctl_max_luns, CTL_DEFAULT_MAX_LUNS);
                ctl_max_luns = CTL_DEFAULT_MAX_LUNS;
        }
        softc->ctl_luns = malloc(sizeof(struct ctl_lun *) * ctl_max_luns,
            M_DEVBUF, M_WAITOK | M_ZERO);
        softc->ctl_lun_mask = malloc(sizeof(uint32_t) *
            ((ctl_max_luns + 31) / 32), M_DEVBUF, M_WAITOK | M_ZERO);
        if (ctl_max_ports <= 0 || powerof2(ctl_max_ports) == 0) {
                printf("Bad value %d for kern.cam.ctl.max_ports, must be a power of two, using %d\n",
                    ctl_max_ports, CTL_DEFAULT_MAX_PORTS);
                ctl_max_ports = CTL_DEFAULT_MAX_PORTS;
        }
        softc->ctl_port_mask = malloc(sizeof(uint32_t) *
          ((ctl_max_ports + 31) / 32), M_DEVBUF, M_WAITOK | M_ZERO);
        softc->ctl_ports = malloc(sizeof(struct ctl_port *) * ctl_max_ports,
             M_DEVBUF, M_WAITOK | M_ZERO);


        /*
         * In Copan's HA scheme, the "master" and "slave" roles are
         * figured out through the slot the controller is in.  Although it
         * is an active/active system, someone has to be in charge.
         */
        SYSCTL_ADD_INT(&softc->sysctl_ctx, SYSCTL_CHILDREN(softc->sysctl_tree),
            OID_AUTO, "ha_id", CTLFLAG_RDTUN, &softc->ha_id, 0,
            "HA head ID (0 - no HA)");
        if (softc->ha_id == 0 || softc->ha_id > NUM_HA_SHELVES) {
                softc->flags |= CTL_FLAG_ACTIVE_SHELF;
                softc->is_single = 1;
                softc->port_cnt = ctl_max_ports;
                softc->port_min = 0;
        } else {
                softc->port_cnt = ctl_max_ports / NUM_HA_SHELVES;
                softc->port_min = (softc->ha_id - 1) * softc->port_cnt;
        }
        softc->port_max = softc->port_min + softc->port_cnt;
        softc->init_min = softc->port_min * CTL_MAX_INIT_PER_PORT;
        softc->init_max = softc->port_max * CTL_MAX_INIT_PER_PORT;

        SYSCTL_ADD_INT(&softc->sysctl_ctx, SYSCTL_CHILDREN(softc->sysctl_tree),
            OID_AUTO, "ha_link", CTLFLAG_RD, (int *)&softc->ha_link, 0,
            "HA link state (0 - offline, 1 - unknown, 2 - online)");

        STAILQ_INIT(&softc->lun_list);
        STAILQ_INIT(&softc->fe_list);
        STAILQ_INIT(&softc->port_list);
        STAILQ_INIT(&softc->be_list);
        ctl_tpc_init(softc);

        if (worker_threads <= 0)
                worker_threads = max(1, mp_ncpus / 4);
        if (worker_threads > CTL_MAX_THREADS)
                worker_threads = CTL_MAX_THREADS;

        for (i = 0; i < worker_threads; i++) {
                struct ctl_thread *thr = &softc->threads[i];

                mtx_init(&thr->queue_lock, "CTL queue mutex", NULL, MTX_DEF);
                thr->ctl_softc = softc;
                STAILQ_INIT(&thr->incoming_queue);
                STAILQ_INIT(&thr->rtr_queue);
                STAILQ_INIT(&thr->done_queue);
                STAILQ_INIT(&thr->isc_queue);

                error = kproc_kthread_add(ctl_work_thread, thr,
                    &softc->ctl_proc, &thr->thread, 0, 0, "ctl", "work%d", i);
                if (error != 0) {
                        printf("error creating CTL work thread!\n");
                        return (error);
                }
        }
        error = kproc_kthread_add(ctl_thresh_thread, softc,
            &softc->ctl_proc, &softc->thresh_thread, 0, 0, "ctl", "thresh");
        if (error != 0) {
                printf("error creating CTL threshold thread!\n");
                return (error);
        }

        SYSCTL_ADD_PROC(&softc->sysctl_ctx,SYSCTL_CHILDREN(softc->sysctl_tree),
            OID_AUTO, "ha_role",
            CTLTYPE_INT | CTLFLAG_RWTUN | CTLFLAG_NEEDGIANT,
            softc, 0, ctl_ha_role_sysctl, "I", "HA role for this head");

        if (softc->is_single == 0) {
                if (ctl_frontend_register(&ha_frontend) != 0)
                        softc->is_single = 1;
        }
        return (0);
}

static int
ctl_shutdown(void)
{
        struct ctl_softc *softc = control_softc;
        int i;

        if (softc->is_single == 0)
                ctl_frontend_deregister(&ha_frontend);

        destroy_dev(softc->dev);

        /* Shutdown CTL threads. */
        softc->shutdown = 1;
        for (i = 0; i < worker_threads; i++) {
                struct ctl_thread *thr = &softc->threads[i];
                while (thr->thread != NULL) {
                        wakeup(thr);
                        if (thr->thread != NULL)
                                pause("CTL thr shutdown", 1);
                }
                mtx_destroy(&thr->queue_lock);
        }
        while (softc->thresh_thread != NULL) {
                wakeup(softc->thresh_thread);
                if (softc->thresh_thread != NULL)
                        pause("CTL thr shutdown", 1);
        }

        ctl_tpc_shutdown(softc);
        uma_zdestroy(softc->io_zone);
        mtx_destroy(&softc->ctl_lock);

        free(softc->ctl_luns, M_DEVBUF);
        free(softc->ctl_lun_mask, M_DEVBUF);
        free(softc->ctl_port_mask, M_DEVBUF);
        free(softc->ctl_ports, M_DEVBUF);

        sysctl_ctx_free(&softc->sysctl_ctx);

        free(softc, M_DEVBUF);
        control_softc = NULL;
        return (0);
}

static int
ctl_module_event_handler(module_t mod, int what, void *arg)
{

        switch (what) {
        case MOD_LOAD:
                return (ctl_init());
        case MOD_UNLOAD:
                return (ctl_shutdown());
        default:
                return (EOPNOTSUPP);
        }
}

/*
 * XXX KDM should we do some access checks here?  Bump a reference count to
 * prevent a CTL module from being unloaded while someone has it open?
 */
static int
ctl_open(struct cdev *dev, int flags, int fmt, struct thread *td)
{
        return (0);
}

static int
ctl_close(struct cdev *dev, int flags, int fmt, struct thread *td)
{
        return (0);
}

/*
 * Remove an initiator by port number and initiator ID.
 * Returns 0 for success, -1 for failure.
 */
int
ctl_remove_initiator(struct ctl_port *port, int iid)
{
        struct ctl_softc *softc = port->ctl_softc;
        int last;

        mtx_assert(&softc->ctl_lock, MA_NOTOWNED);

        if (iid > CTL_MAX_INIT_PER_PORT) {
                printf("%s: initiator ID %u > maximun %u!\n",
                       __func__, iid, CTL_MAX_INIT_PER_PORT);
                return (-1);
        }

        mtx_lock(&softc->ctl_lock);
        last = (--port->wwpn_iid[iid].in_use == 0);
        port->wwpn_iid[iid].last_use = time_uptime;
        mtx_unlock(&softc->ctl_lock);
        if (last)
                ctl_i_t_nexus_loss(softc, iid, CTL_UA_POWERON);
        ctl_isc_announce_iid(port, iid);

        return (0);
}

/*
 * Add an initiator to the initiator map.
 * Returns iid for success, < 0 for failure.
 */
int
ctl_add_initiator(struct ctl_port *port, int iid, uint64_t wwpn, char *name)
{
        struct ctl_softc *softc = port->ctl_softc;
        time_t best_time;
        int i, best;

        mtx_assert(&softc->ctl_lock, MA_NOTOWNED);

        if (iid >= CTL_MAX_INIT_PER_PORT) {
                printf("%s: WWPN %#jx initiator ID %u > maximum %u!\n",
                       __func__, wwpn, iid, CTL_MAX_INIT_PER_PORT);
                free(name, M_CTL);
                return (-1);
        }

        mtx_lock(&softc->ctl_lock);

        if (iid < 0 && (wwpn != 0 || name != NULL)) {
                for (i = 0; i < CTL_MAX_INIT_PER_PORT; i++) {
                        if (wwpn != 0 && wwpn == port->wwpn_iid[i].wwpn) {
                                iid = i;
                                break;
                        }
                        if (name != NULL && port->wwpn_iid[i].name != NULL &&
                            strcmp(name, port->wwpn_iid[i].name) == 0) {
                                iid = i;
                                break;
                        }
                }
        }

        if (iid < 0) {
                for (i = 0; i < CTL_MAX_INIT_PER_PORT; i++) {
                        if (port->wwpn_iid[i].in_use == 0 &&
                            port->wwpn_iid[i].wwpn == 0 &&
                            port->wwpn_iid[i].name == NULL) {
                                iid = i;
                                break;
                        }
                }
        }

        if (iid < 0) {
                best = -1;
                best_time = INT32_MAX;
                for (i = 0; i < CTL_MAX_INIT_PER_PORT; i++) {
                        if (port->wwpn_iid[i].in_use == 0) {
                                if (port->wwpn_iid[i].last_use < best_time) {
                                        best = i;
                                        best_time = port->wwpn_iid[i].last_use;
                                }
                        }
                }
                iid = best;
        }

        if (iid < 0) {
                mtx_unlock(&softc->ctl_lock);
                free(name, M_CTL);
                return (-2);
        }

        if (port->wwpn_iid[iid].in_use > 0 && (wwpn != 0 || name != NULL)) {
                /*
                 * This is not an error yet.
                 */
                if (wwpn != 0 && wwpn == port->wwpn_iid[iid].wwpn) {
#if 0
                        printf("%s: port %d iid %u WWPN %#jx arrived"
                            " again\n", __func__, port->targ_port,
                            iid, (uintmax_t)wwpn);
#endif
                        goto take;
                }
                if (name != NULL && port->wwpn_iid[iid].name != NULL &&
                    strcmp(name, port->wwpn_iid[iid].name) == 0) {
#if 0
                        printf("%s: port %d iid %u name '%s' arrived"
                            " again\n", __func__, port->targ_port,
                            iid, name);
#endif
                        goto take;
                }

                /*
                 * This is an error, but what do we do about it?  The
                 * driver is telling us we have a new WWPN for this
                 * initiator ID, so we pretty much need to use it.
                 */
                printf("%s: port %d iid %u WWPN %#jx '%s' arrived,"
                    " but WWPN %#jx '%s' is still at that address\n",
                    __func__, port->targ_port, iid, wwpn, name,
                    (uintmax_t)port->wwpn_iid[iid].wwpn,
                    port->wwpn_iid[iid].name);
        }
take:
        free(port->wwpn_iid[iid].name, M_CTL);
        port->wwpn_iid[iid].name = name;
        port->wwpn_iid[iid].wwpn = wwpn;
        port->wwpn_iid[iid].in_use++;
        mtx_unlock(&softc->ctl_lock);
        ctl_isc_announce_iid(port, iid);

        return (iid);
}

static int
ctl_create_iid(struct ctl_port *port, int iid, uint8_t *buf)
{
        int len;

        switch (port->port_type) {
        case CTL_PORT_FC:
        {
                struct scsi_transportid_fcp *id =
                    (struct scsi_transportid_fcp *)buf;
                if (port->wwpn_iid[iid].wwpn == 0)
                        return (0);
                memset(id, 0, sizeof(*id));
                id->format_protocol = SCSI_PROTO_FC;
                scsi_u64to8b(port->wwpn_iid[iid].wwpn, id->n_port_name);
                return (sizeof(*id));
        }
        case CTL_PORT_ISCSI:
        {
                struct scsi_transportid_iscsi_port *id =
                    (struct scsi_transportid_iscsi_port *)buf;
                if (port->wwpn_iid[iid].name == NULL)
                        return (0);
                memset(id, 0, 256);
                id->format_protocol = SCSI_TRN_ISCSI_FORMAT_PORT |
                    SCSI_PROTO_ISCSI;
                len = strlcpy(id->iscsi_name, port->wwpn_iid[iid].name, 252) + 1;
                len = roundup2(min(len, 252), 4);
                scsi_ulto2b(len, id->additional_length);
                return (sizeof(*id) + len);
        }
        case CTL_PORT_SAS:
        {
                struct scsi_transportid_sas *id =
                    (struct scsi_transportid_sas *)buf;
                if (port->wwpn_iid[iid].wwpn == 0)
                        return (0);
                memset(id, 0, sizeof(*id));
                id->format_protocol = SCSI_PROTO_SAS;
                scsi_u64to8b(port->wwpn_iid[iid].wwpn, id->sas_address);
                return (sizeof(*id));
        }
        default:
        {
                struct scsi_transportid_spi *id =
                    (struct scsi_transportid_spi *)buf;
                memset(id, 0, sizeof(*id));
                id->format_protocol = SCSI_PROTO_SPI;
                scsi_ulto2b(iid, id->scsi_addr);
                scsi_ulto2b(port->targ_port, id->rel_trgt_port_id);
                return (sizeof(*id));
        }
        }
}

/*
 * Serialize a command that went down the "wrong" side, and so was sent to
 * this controller for execution.  The logic is a little different than the
 * standard case in ctl_scsiio_precheck().  Errors in this case need to get
 * sent back to the other side, but in the success case, we execute the
 * command on this side (XFER mode) or tell the other side to execute it
 * (SER_ONLY mode).
 */
static void
ctl_serialize_other_sc_cmd(struct ctl_scsiio *ctsio)
{
        struct ctl_softc *softc = CTL_SOFTC(ctsio);
        struct ctl_port *port = CTL_PORT(ctsio);
        union ctl_ha_msg msg_info;
        struct ctl_lun *lun;
        const struct ctl_cmd_entry *entry;
        union ctl_io *bio;
        uint32_t targ_lun;

        targ_lun = ctsio->io_hdr.nexus.targ_mapped_lun;

        /* Make sure that we know about this port. */
        if (port == NULL || (port->status & CTL_PORT_STATUS_ONLINE) == 0) {
                ctl_set_internal_failure(ctsio, /*sks_valid*/ 0,
                                         /*retry_count*/ 1);
                goto badjuju;
        }

        /* Make sure that we know about this LUN. */
        mtx_lock(&softc->ctl_lock);
        if (targ_lun >= ctl_max_luns ||
            (lun = softc->ctl_luns[targ_lun]) == NULL) {
                mtx_unlock(&softc->ctl_lock);

                /*
                 * The other node would not send this request to us unless
                 * received announce that we are primary node for this LUN.
                 * If this LUN does not exist now, it is probably result of
                 * a race, so respond to initiator in the most opaque way.
                 */
                ctl_set_busy(ctsio);
                goto badjuju;
        }
        mtx_lock(&lun->lun_lock);
        mtx_unlock(&softc->ctl_lock);

        /*
         * If the LUN is invalid, pretend that it doesn't exist.
         * It will go away as soon as all pending I/Os completed.
         */
        if (lun->flags & CTL_LUN_DISABLED) {
                mtx_unlock(&lun->lun_lock);
                ctl_set_busy(ctsio);
                goto badjuju;
        }

        entry = ctl_get_cmd_entry(ctsio, NULL);
        if (ctl_scsiio_lun_check(lun, entry, ctsio) != 0) {
                mtx_unlock(&lun->lun_lock);
                goto badjuju;
        }

        CTL_LUN(ctsio) = lun;
        CTL_BACKEND_LUN(ctsio) = lun->be_lun;

        /*
         * Every I/O goes into the OOA queue for a
         * particular LUN, and stays there until completion.
         */
#ifdef CTL_TIME_IO
        if (TAILQ_EMPTY(&lun->ooa_queue))
                lun->idle_time += getsbinuptime() - lun->last_busy;
#endif
        TAILQ_INSERT_TAIL(&lun->ooa_queue, &ctsio->io_hdr, ooa_links);

        bio = (union ctl_io *)TAILQ_PREV(&ctsio->io_hdr, ctl_ooaq, ooa_links);
        switch (ctl_check_ooa(lun, (union ctl_io *)ctsio, &bio)) {
        case CTL_ACTION_BLOCK:
                ctsio->io_hdr.blocker = bio;
                TAILQ_INSERT_TAIL(&bio->io_hdr.blocked_queue, &ctsio->io_hdr,
                                  blocked_links);
                mtx_unlock(&lun->lun_lock);
                break;
        case CTL_ACTION_PASS:
        case CTL_ACTION_SKIP:
                if (softc->ha_mode == CTL_HA_MODE_XFER) {
                        ctsio->io_hdr.flags |= CTL_FLAG_IS_WAS_ON_RTR;
                        ctl_enqueue_rtr((union ctl_io *)ctsio);
                        mtx_unlock(&lun->lun_lock);
                } else {
                        ctsio->io_hdr.flags &= ~CTL_FLAG_IO_ACTIVE;
                        mtx_unlock(&lun->lun_lock);

                        /* send msg back to other side */
                        msg_info.hdr.original_sc = ctsio->io_hdr.remote_io;
                        msg_info.hdr.serializing_sc = (union ctl_io *)ctsio;
                        msg_info.hdr.msg_type = CTL_MSG_R2R;
                        ctl_ha_msg_send(CTL_HA_CHAN_CTL, &msg_info,
                            sizeof(msg_info.hdr), M_WAITOK);
                }
                break;
        case CTL_ACTION_OVERLAP:
                TAILQ_REMOVE(&lun->ooa_queue, &ctsio->io_hdr, ooa_links);
                mtx_unlock(&lun->lun_lock);
                ctl_set_overlapped_cmd(ctsio);
                goto badjuju;
        case CTL_ACTION_OVERLAP_TAG:
                TAILQ_REMOVE(&lun->ooa_queue, &ctsio->io_hdr, ooa_links);
                mtx_unlock(&lun->lun_lock);
                ctl_set_overlapped_tag(ctsio, ctsio->tag_num);
                goto badjuju;
        case CTL_ACTION_ERROR:
        default:
                TAILQ_REMOVE(&lun->ooa_queue, &ctsio->io_hdr, ooa_links);
                mtx_unlock(&lun->lun_lock);

                ctl_set_internal_failure(ctsio, /*sks_valid*/ 0,
                                         /*retry_count*/ 0);
badjuju:
                ctl_copy_sense_data_back((union ctl_io *)ctsio, &msg_info);
                msg_info.hdr.original_sc = ctsio->io_hdr.remote_io;
                msg_info.hdr.serializing_sc = NULL;
                msg_info.hdr.msg_type = CTL_MSG_BAD_JUJU;
                ctl_ha_msg_send(CTL_HA_CHAN_CTL, &msg_info,
                    sizeof(msg_info.scsi), M_WAITOK);
                ctl_free_io((union ctl_io *)ctsio);
                break;
        }
}

/*
 * Returns 0 for success, errno for failure.
 */
static void
ctl_ioctl_fill_ooa(struct ctl_lun *lun, uint32_t *cur_fill_num,
                   struct ctl_ooa *ooa_hdr, struct ctl_ooa_entry *kern_entries)
{
        union ctl_io *io;

        mtx_lock(&lun->lun_lock);
        for (io = (union ctl_io *)TAILQ_FIRST(&lun->ooa_queue); (io != NULL);
             (*cur_fill_num)++, io = (union ctl_io *)TAILQ_NEXT(&io->io_hdr,
             ooa_links)) {
                struct ctl_ooa_entry *entry;

                /*
                 * If we've got more than we can fit, just count the
                 * remaining entries.
                 */
                if (*cur_fill_num >= ooa_hdr->alloc_num)
                        continue;

                entry = &kern_entries[*cur_fill_num];

                entry->tag_num = io->scsiio.tag_num;
                entry->lun_num = lun->lun;
#ifdef CTL_TIME_IO
                entry->start_bt = io->io_hdr.start_bt;
#endif
                bcopy(io->scsiio.cdb, entry->cdb, io->scsiio.cdb_len);
                entry->cdb_len = io->scsiio.cdb_len;
                if (io->io_hdr.blocker != NULL)
                        entry->cmd_flags |= CTL_OOACMD_FLAG_BLOCKED;

                if (io->io_hdr.flags & CTL_FLAG_DMA_INPROG)
                        entry->cmd_flags |= CTL_OOACMD_FLAG_DMA;

                if (io->io_hdr.flags & CTL_FLAG_ABORT)
                        entry->cmd_flags |= CTL_OOACMD_FLAG_ABORT;

                if (io->io_hdr.flags & CTL_FLAG_IS_WAS_ON_RTR)
                        entry->cmd_flags |= CTL_OOACMD_FLAG_RTR;

                if (io->io_hdr.flags & CTL_FLAG_DMA_QUEUED)
                        entry->cmd_flags |= CTL_OOACMD_FLAG_DMA_QUEUED;

                if (io->io_hdr.flags & CTL_FLAG_STATUS_QUEUED)
                        entry->cmd_flags |= CTL_OOACMD_FLAG_STATUS_QUEUED;

                if (io->io_hdr.flags & CTL_FLAG_STATUS_SENT)
                        entry->cmd_flags |= CTL_OOACMD_FLAG_STATUS_SENT;
        }
        mtx_unlock(&lun->lun_lock);
}

/*
 * Escape characters that are illegal or not recommended in XML.
 */
int
ctl_sbuf_printf_esc(struct sbuf *sb, char *str, int size)
{
        char *end = str + size;
        int retval;

        retval = 0;

        for (; *str && str < end; str++) {
                switch (*str) {
                case '&':
                        retval = sbuf_printf(sb, "&amp;");
                        break;
                case '>':
                        retval = sbuf_printf(sb, "&gt;");
                        break;
                case '<':
                        retval = sbuf_printf(sb, "&lt;");
                        break;
                default:
                        retval = sbuf_putc(sb, *str);
                        break;
                }

                if (retval != 0)
                        break;

        }

        return (retval);
}

static void
ctl_id_sbuf(struct ctl_devid *id, struct sbuf *sb)
{
        struct scsi_vpd_id_descriptor *desc;
        int i;

        if (id == NULL || id->len < 4)
                return;
        desc = (struct scsi_vpd_id_descriptor *)id->data;
        switch (desc->id_type & SVPD_ID_TYPE_MASK) {
        case SVPD_ID_TYPE_T10:
                sbuf_printf(sb, "t10.");
                break;
        case SVPD_ID_TYPE_EUI64:
                sbuf_printf(sb, "eui.");
                break;
        case SVPD_ID_TYPE_NAA:
                sbuf_printf(sb, "naa.");
                break;
        case SVPD_ID_TYPE_SCSI_NAME:
                break;
        }
        switch (desc->proto_codeset & SVPD_ID_CODESET_MASK) {
        case SVPD_ID_CODESET_BINARY:
                for (i = 0; i < desc->length; i++)
                        sbuf_printf(sb, "%02x", desc->identifier[i]);
                break;
        case SVPD_ID_CODESET_ASCII:
                sbuf_printf(sb, "%.*s", (int)desc->length,
                    (char *)desc->identifier);
                break;
        case SVPD_ID_CODESET_UTF8:
                sbuf_printf(sb, "%s", (char *)desc->identifier);
                break;
        }
}

static int
ctl_ioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flag,
          struct thread *td)
{
        struct ctl_softc *softc = dev->si_drv1;
        struct ctl_port *port;
        struct ctl_lun *lun;
        int retval;

        retval = 0;

        switch (cmd) {
        case CTL_IO:
                retval = ctl_ioctl_io(dev, cmd, addr, flag, td);
                break;
        case CTL_ENABLE_PORT:
        case CTL_DISABLE_PORT:
        case CTL_SET_PORT_WWNS: {
                struct ctl_port *port;
                struct ctl_port_entry *entry;

                entry = (struct ctl_port_entry *)addr;
                
                mtx_lock(&softc->ctl_lock);
                STAILQ_FOREACH(port, &softc->port_list, links) {
                        int action, done;

                        if (port->targ_port < softc->port_min ||
                            port->targ_port >= softc->port_max)
                                continue;

                        action = 0;
                        done = 0;
                        if ((entry->port_type == CTL_PORT_NONE)
                         && (entry->targ_port == port->targ_port)) {
                                /*
                                 * If the user only wants to enable or
                                 * disable or set WWNs on a specific port,
                                 * do the operation and we're done.
                                 */
                                action = 1;
                                done = 1;
                        } else if (entry->port_type & port->port_type) {
                                /*
                                 * Compare the user's type mask with the
                                 * particular frontend type to see if we
                                 * have a match.
                                 */
                                action = 1;
                                done = 0;

                                /*
                                 * Make sure the user isn't trying to set
                                 * WWNs on multiple ports at the same time.
                                 */
                                if (cmd == CTL_SET_PORT_WWNS) {
                                        printf("%s: Can't set WWNs on "
                                               "multiple ports\n", __func__);
                                        retval = EINVAL;
                                        break;
                                }
                        }
                        if (action == 0)
                                continue;

                        /*
                         * XXX KDM we have to drop the lock here, because
                         * the online/offline operations can potentially
                         * block.  We need to reference count the frontends
                         * so they can't go away,
                         */
                        if (cmd == CTL_ENABLE_PORT) {
                                mtx_unlock(&softc->ctl_lock);
                                ctl_port_online(port);
                                mtx_lock(&softc->ctl_lock);
                        } else if (cmd == CTL_DISABLE_PORT) {
                                mtx_unlock(&softc->ctl_lock);
                                ctl_port_offline(port);
                                mtx_lock(&softc->ctl_lock);
                        } else if (cmd == CTL_SET_PORT_WWNS) {
                                ctl_port_set_wwns(port,
                                    (entry->flags & CTL_PORT_WWNN_VALID) ?
                                    1 : 0, entry->wwnn,
                                    (entry->flags & CTL_PORT_WWPN_VALID) ?
                                    1 : 0, entry->wwpn);
                        }
                        if (done != 0)
                                break;
                }
                mtx_unlock(&softc->ctl_lock);
                break;
        }
        case CTL_GET_OOA: {
                struct ctl_ooa *ooa_hdr;
                struct ctl_ooa_entry *entries;
                uint32_t cur_fill_num;

                ooa_hdr = (struct ctl_ooa *)addr;

                if ((ooa_hdr->alloc_len == 0)
                 || (ooa_hdr->alloc_num == 0)) {
                        printf("%s: CTL_GET_OOA: alloc len %u and alloc num %u "
                               "must be non-zero\n", __func__,
                               ooa_hdr->alloc_len, ooa_hdr->alloc_num);
                        retval = EINVAL;
                        break;
                }

                if (ooa_hdr->alloc_len != (ooa_hdr->alloc_num *
                    sizeof(struct ctl_ooa_entry))) {
                        printf("%s: CTL_GET_OOA: alloc len %u must be alloc "
                               "num %d * sizeof(struct ctl_ooa_entry) %zd\n",
                               __func__, ooa_hdr->alloc_len,
                               ooa_hdr->alloc_num,sizeof(struct ctl_ooa_entry));
                        retval = EINVAL;
                        break;
                }

                entries = malloc(ooa_hdr->alloc_len, M_CTL, M_WAITOK | M_ZERO);
                if (entries == NULL) {
                        printf("%s: could not allocate %d bytes for OOA "
                               "dump\n", __func__, ooa_hdr->alloc_len);
                        retval = ENOMEM;
                        break;
                }

                mtx_lock(&softc->ctl_lock);
                if ((ooa_hdr->flags & CTL_OOA_FLAG_ALL_LUNS) == 0 &&
                    (ooa_hdr->lun_num >= ctl_max_luns ||
                     softc->ctl_luns[ooa_hdr->lun_num] == NULL)) {
                        mtx_unlock(&softc->ctl_lock);
                        free(entries, M_CTL);
                        printf("%s: CTL_GET_OOA: invalid LUN %ju\n",
                               __func__, (uintmax_t)ooa_hdr->lun_num);
                        retval = EINVAL;
                        break;
                }

                cur_fill_num = 0;

                if (ooa_hdr->flags & CTL_OOA_FLAG_ALL_LUNS) {
                        STAILQ_FOREACH(lun, &softc->lun_list, links) {
                                ctl_ioctl_fill_ooa(lun, &cur_fill_num,
                                    ooa_hdr, entries);
                        }
                } else {
                        lun = softc->ctl_luns[ooa_hdr->lun_num];
                        ctl_ioctl_fill_ooa(lun, &cur_fill_num, ooa_hdr,
                            entries);
                }
                mtx_unlock(&softc->ctl_lock);

                ooa_hdr->fill_num = min(cur_fill_num, ooa_hdr->alloc_num);
                ooa_hdr->fill_len = ooa_hdr->fill_num *
                        sizeof(struct ctl_ooa_entry);
                retval = copyout(entries, ooa_hdr->entries, ooa_hdr->fill_len);
                if (retval != 0) {
                        printf("%s: error copying out %d bytes for OOA dump\n", 
                               __func__, ooa_hdr->fill_len);
                }

                getbinuptime(&ooa_hdr->cur_bt);

                if (cur_fill_num > ooa_hdr->alloc_num) {
                        ooa_hdr->dropped_num = cur_fill_num -ooa_hdr->alloc_num;
                        ooa_hdr->status = CTL_OOA_NEED_MORE_SPACE;
                } else {
                        ooa_hdr->dropped_num = 0;
                        ooa_hdr->status = CTL_OOA_OK;
                }

                free(entries, M_CTL);
                break;
        }
        case CTL_DELAY_IO: {
                struct ctl_io_delay_info *delay_info;

                delay_info = (struct ctl_io_delay_info *)addr;

#ifdef CTL_IO_DELAY
                mtx_lock(&softc->ctl_lock);
                if (delay_info->lun_id >= ctl_max_luns ||
                    (lun = softc->ctl_luns[delay_info->lun_id]) == NULL) {
                        mtx_unlock(&softc->ctl_lock);
                        delay_info->status = CTL_DELAY_STATUS_INVALID_LUN;
                        break;
                }
                mtx_lock(&lun->lun_lock);
                mtx_unlock(&softc->ctl_lock);
                delay_info->status = CTL_DELAY_STATUS_OK;
                switch (delay_info->delay_type) {
                case CTL_DELAY_TYPE_CONT:
                case CTL_DELAY_TYPE_ONESHOT:
                        break;
                default:
                        delay_info->status = CTL_DELAY_STATUS_INVALID_TYPE;
                        break;
                }
                switch (delay_info->delay_loc) {
                case CTL_DELAY_LOC_DATAMOVE:
                        lun->delay_info.datamove_type = delay_info->delay_type;
                        lun->delay_info.datamove_delay = delay_info->delay_secs;
                        break;
                case CTL_DELAY_LOC_DONE:
                        lun->delay_info.done_type = delay_info->delay_type;
                        lun->delay_info.done_delay = delay_info->delay_secs;
                        break;
                default:
                        delay_info->status = CTL_DELAY_STATUS_INVALID_LOC;
                        break;
                }
                mtx_unlock(&lun->lun_lock);
#else
                delay_info->status = CTL_DELAY_STATUS_NOT_IMPLEMENTED;
#endif /* CTL_IO_DELAY */
                break;
        }
        case CTL_ERROR_INJECT: {
                struct ctl_error_desc *err_desc, *new_err_desc;

                err_desc = (struct ctl_error_desc *)addr;

                new_err_desc = malloc(sizeof(*new_err_desc), M_CTL,
                                      M_WAITOK | M_ZERO);
                bcopy(err_desc, new_err_desc, sizeof(*new_err_desc));

                mtx_lock(&softc->ctl_lock);
                if (err_desc->lun_id >= ctl_max_luns ||
                    (lun = softc->ctl_luns[err_desc->lun_id]) == NULL) {
                        mtx_unlock(&softc->ctl_lock);
                        free(new_err_desc, M_CTL);
                        printf("%s: CTL_ERROR_INJECT: invalid LUN %ju\n",
                               __func__, (uintmax_t)err_desc->lun_id);
                        retval = EINVAL;
                        break;
                }
                mtx_lock(&lun->lun_lock);
                mtx_unlock(&softc->ctl_lock);

                /*
                 * We could do some checking here to verify the validity
                 * of the request, but given the complexity of error
                 * injection requests, the checking logic would be fairly
                 * complex.
                 *
                 * For now, if the request is invalid, it just won't get
                 * executed and might get deleted.
                 */
                STAILQ_INSERT_TAIL(&lun->error_list, new_err_desc, links);

                /*
                 * XXX KDM check to make sure the serial number is unique,
                 * in case we somehow manage to wrap.  That shouldn't
                 * happen for a very long time, but it's the right thing to
                 * do.
                 */
                new_err_desc->serial = lun->error_serial;
                err_desc->serial = lun->error_serial;
                lun->error_serial++;

                mtx_unlock(&lun->lun_lock);
                break;
        }
        case CTL_ERROR_INJECT_DELETE: {
                struct ctl_error_desc *delete_desc, *desc, *desc2;
                int delete_done;

                delete_desc = (struct ctl_error_desc *)addr;
                delete_done = 0;

                mtx_lock(&softc->ctl_lock);
                if (delete_desc->lun_id >= ctl_max_luns ||
                    (lun = softc->ctl_luns[delete_desc->lun_id]) == NULL) {
                        mtx_unlock(&softc->ctl_lock);
                        printf("%s: CTL_ERROR_INJECT_DELETE: invalid LUN %ju\n",
                               __func__, (uintmax_t)delete_desc->lun_id);
                        retval = EINVAL;
                        break;
                }
                mtx_lock(&lun->lun_lock);
                mtx_unlock(&softc->ctl_lock);
                STAILQ_FOREACH_SAFE(desc, &lun->error_list, links, desc2) {
                        if (desc->serial != delete_desc->serial)
                                continue;

                        STAILQ_REMOVE(&lun->error_list, desc, ctl_error_desc,
                                      links);
                        free(desc, M_CTL);
                        delete_done = 1;
                }
                mtx_unlock(&lun->lun_lock);
                if (delete_done == 0) {
                        printf("%s: CTL_ERROR_INJECT_DELETE: can't find "
                               "error serial %ju on LUN %u\n", __func__, 
                               delete_desc->serial, delete_desc->lun_id);
                        retval = EINVAL;
                        break;
                }
                break;
        }
        case CTL_DUMP_STRUCTS: {
                int j, k;
                struct ctl_port *port;
                struct ctl_frontend *fe;

                mtx_lock(&softc->ctl_lock);
                printf("CTL Persistent Reservation information start:\n");
                STAILQ_FOREACH(lun, &softc->lun_list, links) {
                        mtx_lock(&lun->lun_lock);
                        if ((lun->flags & CTL_LUN_DISABLED) != 0) {
                                mtx_unlock(&lun->lun_lock);
                                continue;
                        }

                        for (j = 0; j < ctl_max_ports; j++) {
                                if (lun->pr_keys[j] == NULL)
                                        continue;
                                for (k = 0; k < CTL_MAX_INIT_PER_PORT; k++){
                                        if (lun->pr_keys[j][k] == 0)
                                                continue;
                                        printf("  LUN %ju port %d iid %d key "
                                               "%#jx\n", lun->lun, j, k,
                                               (uintmax_t)lun->pr_keys[j][k]);
                                }
                        }
                        mtx_unlock(&lun->lun_lock);
                }
                printf("CTL Persistent Reservation information end\n");
                printf("CTL Ports:\n");
                STAILQ_FOREACH(port, &softc->port_list, links) {
                        printf("  Port %d '%s' Frontend '%s' Type %u pp %d vp %d WWNN "
                               "%#jx WWPN %#jx\n", port->targ_port, port->port_name,
                               port->frontend->name, port->port_type,
                               port->physical_port, port->virtual_port,
                               (uintmax_t)port->wwnn, (uintmax_t)port->wwpn);
                        for (j = 0; j < CTL_MAX_INIT_PER_PORT; j++) {
                                if (port->wwpn_iid[j].in_use == 0 &&
                                    port->wwpn_iid[j].wwpn == 0 &&
                                    port->wwpn_iid[j].name == NULL)
                                        continue;

                                printf("    iid %u use %d WWPN %#jx '%s'\n",
                                    j, port->wwpn_iid[j].in_use,
                                    (uintmax_t)port->wwpn_iid[j].wwpn,
                                    port->wwpn_iid[j].name);
                        }
                }
                printf("CTL Port information end\n");
                mtx_unlock(&softc->ctl_lock);
                /*
                 * XXX KDM calling this without a lock.  We'd likely want
                 * to drop the lock before calling the frontend's dump
                 * routine anyway.
                 */
                printf("CTL Frontends:\n");
                STAILQ_FOREACH(fe, &softc->fe_list, links) {
                        printf("  Frontend '%s'\n", fe->name);
                        if (fe->fe_dump != NULL)
                                fe->fe_dump();
                }
                printf("CTL Frontend information end\n");
                break;
        }
        case CTL_LUN_REQ: {
                struct ctl_lun_req *lun_req;
                struct ctl_backend_driver *backend;
                void *packed;
                nvlist_t *tmp_args_nvl;
                size_t packed_len;

                lun_req = (struct ctl_lun_req *)addr;
                tmp_args_nvl = lun_req->args_nvl;

                backend = ctl_backend_find(lun_req->backend);
                if (backend == NULL) {
                        lun_req->status = CTL_LUN_ERROR;
                        snprintf(lun_req->error_str,
                                 sizeof(lun_req->error_str),
                                 "Backend \"%s\" not found.",
                                 lun_req->backend);
                        break;
                }

                if (lun_req->args != NULL) {
                        packed = malloc(lun_req->args_len, M_CTL, M_WAITOK);
                        if (copyin(lun_req->args, packed, lun_req->args_len) != 0) {
                                free(packed, M_CTL);
                                lun_req->status = CTL_LUN_ERROR;
                                snprintf(lun_req->error_str, sizeof(lun_req->error_str),
                                    "Cannot copyin args.");
                                break;
                        }
                        lun_req->args_nvl = nvlist_unpack(packed,
                            lun_req->args_len, 0);
                        free(packed, M_CTL);

                        if (lun_req->args_nvl == NULL) {
                                lun_req->status = CTL_LUN_ERROR;
                                snprintf(lun_req->error_str, sizeof(lun_req->error_str),
                                    "Cannot unpack args nvlist.");
                                break;
                        }
                } else
                        lun_req->args_nvl = nvlist_create(0);

                retval = backend->ioctl(dev, cmd, addr, flag, td);
                nvlist_destroy(lun_req->args_nvl);
                lun_req->args_nvl = tmp_args_nvl;

                if (lun_req->result_nvl != NULL) {
                        if (lun_req->result != NULL) {
                                packed = nvlist_pack(lun_req->result_nvl,
                                    &packed_len);
                                if (packed == NULL) {
                                        lun_req->status = CTL_LUN_ERROR;
                                        snprintf(lun_req->error_str,
                                            sizeof(lun_req->error_str),
                                            "Cannot pack result nvlist.");
                                        break;
                                }

                                if (packed_len > lun_req->result_len) {
                                        lun_req->status = CTL_LUN_ERROR;
                                        snprintf(lun_req->error_str,
                                            sizeof(lun_req->error_str),
                                            "Result nvlist too large.");
                                        free(packed, M_NVLIST);
                                        break;
                                }

                                if (copyout(packed, lun_req->result, packed_len)) {
                                        lun_req->status = CTL_LUN_ERROR;
                                        snprintf(lun_req->error_str,
                                            sizeof(lun_req->error_str),
                                            "Cannot copyout() the result.");
                                        free(packed, M_NVLIST);
                                        break;
                                }

                                lun_req->result_len = packed_len;
                                free(packed, M_NVLIST);
                        }

                        nvlist_destroy(lun_req->result_nvl);
                }
                break;
        }
        case CTL_LUN_LIST: {
                struct sbuf *sb;
                struct ctl_lun_list *list;
                const char *name, *value;
                void *cookie;
                int type;

                list = (struct ctl_lun_list *)addr;

                /*
                 * Allocate a fixed length sbuf here, based on the length
                 * of the user's buffer.  We could allocate an auto-extending
                 * buffer, and then tell the user how much larger our
                 * amount of data is than his buffer, but that presents
                 * some problems:
                 *
                 * 1.  The sbuf(9) routines use a blocking malloc, and so
                 *     we can't hold a lock while calling them with an
                 *     auto-extending buffer.
                 *
                 * 2.  There is not currently a LUN reference counting
                 *     mechanism, outside of outstanding transactions on
                 *     the LUN's OOA queue.  So a LUN could go away on us
                 *     while we're getting the LUN number, backend-specific
                 *     information, etc.  Thus, given the way things
                 *     currently work, we need to hold the CTL lock while
                 *     grabbing LUN information.
                 *
                 * So, from the user's standpoint, the best thing to do is
                 * allocate what he thinks is a reasonable buffer length,
                 * and then if he gets a CTL_LUN_LIST_NEED_MORE_SPACE error,
                 * double the buffer length and try again.  (And repeat
                 * that until he succeeds.)
                 */
                sb = sbuf_new(NULL, NULL, list->alloc_len, SBUF_FIXEDLEN);
                if (sb == NULL) {
                        list->status = CTL_LUN_LIST_ERROR;
                        snprintf(list->error_str, sizeof(list->error_str),
                                 "Unable to allocate %d bytes for LUN list",
                                 list->alloc_len);
                        break;
                }

                sbuf_printf(sb, "<ctllunlist>\n");

                mtx_lock(&softc->ctl_lock);
                STAILQ_FOREACH(lun, &softc->lun_list, links) {
                        mtx_lock(&lun->lun_lock);
                        retval = sbuf_printf(sb, "<lun id=\"%ju\">\n",
                                             (uintmax_t)lun->lun);

                        /*
                         * Bail out as soon as we see that we've overfilled
                         * the buffer.
                         */
                        if (retval != 0)
                                break;

                        retval = sbuf_printf(sb, "\t<backend_type>%s"
                                             "</backend_type>\n",
                                             (lun->backend == NULL) ?  "none" :
                                             lun->backend->name);

                        if (retval != 0)
                                break;

                        retval = sbuf_printf(sb, "\t<lun_type>%d</lun_type>\n",
                                             lun->be_lun->lun_type);

                        if (retval != 0)
                                break;

                        if (lun->backend == NULL) {
                                retval = sbuf_printf(sb, "</lun>\n");
                                if (retval != 0)
                                        break;
                                continue;
                        }

                        retval = sbuf_printf(sb, "\t<size>%ju</size>\n",
                                             (lun->be_lun->maxlba > 0) ?
                                             lun->be_lun->maxlba + 1 : 0);

                        if (retval != 0)
                                break;

                        retval = sbuf_printf(sb, "\t<blocksize>%u</blocksize>\n",
                                             lun->be_lun->blocksize);

                        if (retval != 0)
                                break;

                        retval = sbuf_printf(sb, "\t<serial_number>");

                        if (retval != 0)
                                break;

                        retval = ctl_sbuf_printf_esc(sb,
                            lun->be_lun->serial_num,
                            sizeof(lun->be_lun->serial_num));

                        if (retval != 0)
                                break;

                        retval = sbuf_printf(sb, "</serial_number>\n");
                
                        if (retval != 0)
                                break;

                        retval = sbuf_printf(sb, "\t<device_id>");

                        if (retval != 0)
                                break;

                        retval = ctl_sbuf_printf_esc(sb,
                            lun->be_lun->device_id,
                            sizeof(lun->be_lun->device_id));

                        if (retval != 0)
                                break;

                        retval = sbuf_printf(sb, "</device_id>\n");

                        if (retval != 0)
                                break;

                        if (lun->backend->lun_info != NULL) {
                                retval = lun->backend->lun_info(lun->be_lun, sb);
                                if (retval != 0)
                                        break;
                        }

                        cookie = NULL;
                        while ((name = nvlist_next(lun->be_lun->options, &type,
                            &cookie)) != NULL) {
                                sbuf_printf(sb, "\t<%s>", name);

                                if (type == NV_TYPE_STRING) {
                                        value = dnvlist_get_string(
                                            lun->be_lun->options, name, NULL);
                                        if (value != NULL)
                                                sbuf_printf(sb, "%s", value);
                                }

                                sbuf_printf(sb, "</%s>\n", name);
                        }

                        retval = sbuf_printf(sb, "</lun>\n");

                        if (retval != 0)
                                break;
                        mtx_unlock(&lun->lun_lock);
                }
                if (lun != NULL)
                        mtx_unlock(&lun->lun_lock);
                mtx_unlock(&softc->ctl_lock);

                if ((retval != 0)
                 || ((retval = sbuf_printf(sb, "</ctllunlist>\n")) != 0)) {
                        retval = 0;
                        sbuf_delete(sb);
                        list->status = CTL_LUN_LIST_NEED_MORE_SPACE;
                        snprintf(list->error_str, sizeof(list->error_str),
                                 "Out of space, %d bytes is too small",
                                 list->alloc_len);
                        break;
                }

                sbuf_finish(sb);

                retval = copyout(sbuf_data(sb), list->lun_xml,
                                 sbuf_len(sb) + 1);

                list->fill_len = sbuf_len(sb) + 1;
                list->status = CTL_LUN_LIST_OK;
                sbuf_delete(sb);
                break;
        }
        case CTL_ISCSI: {
                struct ctl_iscsi *ci;
                struct ctl_frontend *fe;

                ci = (struct ctl_iscsi *)addr;

                fe = ctl_frontend_find("iscsi");
                if (fe == NULL) {
                        ci->status = CTL_ISCSI_ERROR;
                        snprintf(ci->error_str, sizeof(ci->error_str),
                            "Frontend \"iscsi\" not found.");
                        break;
                }

                retval = fe->ioctl(dev, cmd, addr, flag, td);
                break;
        }
        case CTL_PORT_REQ: {
                struct ctl_req *req;
                struct ctl_frontend *fe;
                void *packed;
                nvlist_t *tmp_args_nvl;
                size_t packed_len;

                req = (struct ctl_req *)addr;
                tmp_args_nvl = req->args_nvl;

                fe = ctl_frontend_find(req->driver);
                if (fe == NULL) {
                        req->status = CTL_LUN_ERROR;
                        snprintf(req->error_str, sizeof(req->error_str),
                            "Frontend \"%s\" not found.", req->driver);
                        break;
                }

                if (req->args != NULL) {
                        packed = malloc(req->args_len, M_CTL, M_WAITOK);
                        if (copyin(req->args, packed, req->args_len) != 0) {
                                free(packed, M_CTL);
                                req->status = CTL_LUN_ERROR;
                                snprintf(req->error_str, sizeof(req->error_str),
                                    "Cannot copyin args.");
                                break;
                        }
                        req->args_nvl = nvlist_unpack(packed,
                            req->args_len, 0);
                        free(packed, M_CTL);

                        if (req->args_nvl == NULL) {
                                req->status = CTL_LUN_ERROR;
                                snprintf(req->error_str, sizeof(req->error_str),
                                    "Cannot unpack args nvlist.");
                                break;
                        }
                } else
                        req->args_nvl = nvlist_create(0);

                if (fe->ioctl)
                        retval = fe->ioctl(dev, cmd, addr, flag, td);
                else
                        retval = ENODEV;

                nvlist_destroy(req->args_nvl);
                req->args_nvl = tmp_args_nvl;

                if (req->result_nvl != NULL) {
                        if (req->result != NULL) {
                                packed = nvlist_pack(req->result_nvl,
                                    &packed_len);
                                if (packed == NULL) {
                                        req->status = CTL_LUN_ERROR;
                                        snprintf(req->error_str,
                                            sizeof(req->error_str),
                                            "Cannot pack result nvlist.");
                                        break;
                                }

                                if (packed_len > req->result_len) {
                                        req->status = CTL_LUN_ERROR;
                                        snprintf(req->error_str,
                                            sizeof(req->error_str),
                                            "Result nvlist too large.");
                                        free(packed, M_NVLIST);
                                        break;
                                }

                                if (copyout(packed, req->result, packed_len)) {
                                        req->status = CTL_LUN_ERROR;
                                        snprintf(req->error_str,
                                            sizeof(req->error_str),
                                            "Cannot copyout() the result.");
                                        free(packed, M_NVLIST);
                                        break;
                                }

                                req->result_len = packed_len;
                                free(packed, M_NVLIST);
                        }

                        nvlist_destroy(req->result_nvl);
                }
                break;
        }
        case CTL_PORT_LIST: {
                struct sbuf *sb;
                struct ctl_port *port;
                struct ctl_lun_list *list;
                const char *name, *value;
                void *cookie;
                int j, type;
                uint32_t plun;

                list = (struct ctl_lun_list *)addr;

                sb = sbuf_new(NULL, NULL, list->alloc_len, SBUF_FIXEDLEN);
                if (sb == NULL) {
                        list->status = CTL_LUN_LIST_ERROR;
                        snprintf(list->error_str, sizeof(list->error_str),
                                 "Unable to allocate %d bytes for LUN list",
                                 list->alloc_len);
                        break;
                }

                sbuf_printf(sb, "<ctlportlist>\n");

                mtx_lock(&softc->ctl_lock);
                STAILQ_FOREACH(port, &softc->port_list, links) {
                        retval = sbuf_printf(sb, "<targ_port id=\"%ju\">\n",
                                             (uintmax_t)port->targ_port);

                        /*
                         * Bail out as soon as we see that we've overfilled
                         * the buffer.
                         */
                        if (retval != 0)
                                break;

                        retval = sbuf_printf(sb, "\t<frontend_type>%s"
                            "</frontend_type>\n", port->frontend->name);
                        if (retval != 0)
                                break;

                        retval = sbuf_printf(sb, "\t<port_type>%d</port_type>\n",
                                             port->port_type);
                        if (retval != 0)
                                break;

                        retval = sbuf_printf(sb, "\t<online>%s</online>\n",
                            (port->status & CTL_PORT_STATUS_ONLINE) ? "YES" : "NO");
                        if (retval != 0)
                                break;

                        retval = sbuf_printf(sb, "\t<port_name>%s</port_name>\n",
                            port->port_name);
                        if (retval != 0)
                                break;

                        retval = sbuf_printf(sb, "\t<physical_port>%d</physical_port>\n",
                            port->physical_port);
                        if (retval != 0)
                                break;

                        retval = sbuf_printf(sb, "\t<virtual_port>%d</virtual_port>\n",
                            port->virtual_port);
                        if (retval != 0)
                                break;

                        if (port->target_devid != NULL) {
                                sbuf_printf(sb, "\t<target>");
                                ctl_id_sbuf(port->target_devid, sb);
                                sbuf_printf(sb, "</target>\n");
                        }

                        if (port->port_devid != NULL) {
                                sbuf_printf(sb, "\t<port>");
                                ctl_id_sbuf(port->port_devid, sb);
                                sbuf_printf(sb, "</port>\n");
                        }

                        if (port->port_info != NULL) {
                                retval = port->port_info(port->onoff_arg, sb);
                                if (retval != 0)
                                        break;
                        }

                        cookie = NULL;
                        while ((name = nvlist_next(port->options, &type,
                            &cookie)) != NULL) {
                                sbuf_printf(sb, "\t<%s>", name);

                                if (type == NV_TYPE_STRING) {
                                        value = dnvlist_get_string(port->options,
                                            name, NULL);
                                        if (value != NULL)
                                                sbuf_printf(sb, "%s", value);
                                }

                                sbuf_printf(sb, "</%s>\n", name);
                        }

                        if (port->lun_map != NULL) {
                                sbuf_printf(sb, "\t<lun_map>on</lun_map>\n");
                                for (j = 0; j < port->lun_map_size; j++) {
                                        plun = ctl_lun_map_from_port(port, j);
                                        if (plun == UINT32_MAX)
                                                continue;
                                        sbuf_printf(sb,
                                            "\t<lun id=\"%u\">%u</lun>\n",
                                            j, plun);
                                }
                        }

                        for (j = 0; j < CTL_MAX_INIT_PER_PORT; j++) {
                                if (port->wwpn_iid[j].in_use == 0 ||
                                    (port->wwpn_iid[j].wwpn == 0 &&
                                     port->wwpn_iid[j].name == NULL))
                                        continue;

                                if (port->wwpn_iid[j].name != NULL)
                                        retval = sbuf_printf(sb,
                                            "\t<initiator id=\"%u\">%s</initiator>\n",
                                            j, port->wwpn_iid[j].name);
                                else
                                        retval = sbuf_printf(sb,
                                            "\t<initiator id=\"%u\">naa.%08jx</initiator>\n",
                                            j, port->wwpn_iid[j].wwpn);
                                if (retval != 0)
                                        break;
                        }
                        if (retval != 0)
                                break;

                        retval = sbuf_printf(sb, "</targ_port>\n");
                        if (retval != 0)
                                break;
                }
                mtx_unlock(&softc->ctl_lock);

                if ((retval != 0)
                 || ((retval = sbuf_printf(sb, "</ctlportlist>\n")) != 0)) {
                        retval = 0;
                        sbuf_delete(sb);
                        list->status = CTL_LUN_LIST_NEED_MORE_SPACE;
                        snprintf(list->error_str, sizeof(list->error_str),
                                 "Out of space, %d bytes is too small",
                                 list->alloc_len);
                        break;
                }

                sbuf_finish(sb);

                retval = copyout(sbuf_data(sb), list->lun_xml,
                                 sbuf_len(sb) + 1);

                list->fill_len = sbuf_len(sb) + 1;
                list->status = CTL_LUN_LIST_OK;
                sbuf_delete(sb);
                break;
        }
        case CTL_LUN_MAP: {
                struct ctl_lun_map *lm  = (struct ctl_lun_map *)addr;
                struct ctl_port *port;

                mtx_lock(&softc->ctl_lock);
                if (lm->port < softc->port_min ||
                    lm->port >= softc->port_max ||
                    (port = softc->ctl_ports[lm->port]) == NULL) {
                        mtx_unlock(&softc->ctl_lock);
                        return (ENXIO);
                }
                if (port->status & CTL_PORT_STATUS_ONLINE) {
                        STAILQ_FOREACH(lun, &softc->lun_list, links) {
                                if (ctl_lun_map_to_port(port, lun->lun) ==
                                    UINT32_MAX)
                                        continue;
                                mtx_lock(&lun->lun_lock);
                                ctl_est_ua_port(lun, lm->port, -1,
                                    CTL_UA_LUN_CHANGE);
                                mtx_unlock(&lun->lun_lock);
                        }
                }
                mtx_unlock(&softc->ctl_lock); // XXX: port_enable sleeps
                if (lm->plun != UINT32_MAX) {
                        if (lm->lun == UINT32_MAX)
                                retval = ctl_lun_map_unset(port, lm->plun);
                        else if (lm->lun < ctl_max_luns &&
                            softc->ctl_luns[lm->lun] != NULL)
                                retval = ctl_lun_map_set(port, lm->plun, lm->lun);
                        else
                                return (ENXIO);
                } else {
                        if (lm->lun == UINT32_MAX)
                                retval = ctl_lun_map_deinit(port);
                        else
                                retval = ctl_lun_map_init(port);
                }
                if (port->status & CTL_PORT_STATUS_ONLINE)
                        ctl_isc_announce_port(port);
                break;
        }
        case CTL_GET_LUN_STATS: {
                struct ctl_get_io_stats *stats = (struct ctl_get_io_stats *)addr;
                int i;

                /*
                 * XXX KDM no locking here.  If the LUN list changes,
                 * things can blow up.
                 */
                i = 0;
                stats->status = CTL_SS_OK;
                stats->fill_len = 0;
                STAILQ_FOREACH(lun, &softc->lun_list, links) {
                        if (lun->lun < stats->first_item)
                                continue;
                        if (stats->fill_len + sizeof(lun->stats) >
                            stats->alloc_len) {
                                stats->status = CTL_SS_NEED_MORE_SPACE;
                                break;
                        }
                        retval = copyout(&lun->stats, &stats->stats[i++],
                                         sizeof(lun->stats));
                        if (retval != 0)
                                break;
                        stats->fill_len += sizeof(lun->stats);
                }
                stats->num_items = softc->num_luns;
                stats->flags = CTL_STATS_FLAG_NONE;
#ifdef CTL_TIME_IO
                stats->flags |= CTL_STATS_FLAG_TIME_VALID;
#endif
                getnanouptime(&stats->timestamp);
                break;
        }
        case CTL_GET_PORT_STATS: {
                struct ctl_get_io_stats *stats = (struct ctl_get_io_stats *)addr;
                int i;

                /*
                 * XXX KDM no locking here.  If the LUN list changes,
                 * things can blow up.
                 */
                i = 0;
                stats->status = CTL_SS_OK;
                stats->fill_len = 0;
                STAILQ_FOREACH(port, &softc->port_list, links) {
                        if (port->targ_port < stats->first_item)
                                continue;
                        if (stats->fill_len + sizeof(port->stats) >
                            stats->alloc_len) {
                                stats->status = CTL_SS_NEED_MORE_SPACE;
                                break;
                        }
                        retval = copyout(&port->stats, &stats->stats[i++],
                                         sizeof(port->stats));
                        if (retval != 0)
                                break;
                        stats->fill_len += sizeof(port->stats);
                }
                stats->num_items = softc->num_ports;
                stats->flags = CTL_STATS_FLAG_NONE;
#ifdef CTL_TIME_IO
                stats->flags |= CTL_STATS_FLAG_TIME_VALID;
#endif
                getnanouptime(&stats->timestamp);
                break;
        }
        default: {
                /* XXX KDM should we fix this? */
#if 0
                struct ctl_backend_driver *backend;
                unsigned int type;
                int found;

                found = 0;

                /*
                 * We encode the backend type as the ioctl type for backend
                 * ioctls.  So parse it out here, and then search for a
                 * backend of this type.
                 */
                type = _IOC_TYPE(cmd);

                STAILQ_FOREACH(backend, &softc->be_list, links) {
                        if (backend->type == type) {
                                found = 1;
                                break;
                        }
                }
                if (found == 0) {
                        printf("ctl: unknown ioctl command %#lx or backend "
                               "%d\n", cmd, type);
                        retval = EINVAL;
                        break;
                }
                retval = backend->ioctl(dev, cmd, addr, flag, td);
#endif
                retval = ENOTTY;
                break;
        }
        }
        return (retval);
}

uint32_t
ctl_get_initindex(struct ctl_nexus *nexus)
{
        return (nexus->initid + (nexus->targ_port * CTL_MAX_INIT_PER_PORT));
}

int
ctl_lun_map_init(struct ctl_port *port)
{
        struct ctl_softc *softc = port->ctl_softc;
        struct ctl_lun *lun;
        int size = ctl_lun_map_size;
        uint32_t i;

        if (port->lun_map == NULL || port->lun_map_size < size) {
                port->lun_map_size = 0;
                free(port->lun_map, M_CTL);
                port->lun_map = malloc(size * sizeof(uint32_t),
                    M_CTL, M_NOWAIT);
        }
        if (port->lun_map == NULL)
                return (ENOMEM);
        for (i = 0; i < size; i++)
                port->lun_map[i] = UINT32_MAX;
        port->lun_map_size = size;
        if (port->status & CTL_PORT_STATUS_ONLINE) {
                if (port->lun_disable != NULL) {
                        STAILQ_FOREACH(lun, &softc->lun_list, links)
                                port->lun_disable(port->targ_lun_arg, lun->lun);
                }
                ctl_isc_announce_port(port);
        }
        return (0);
}

int
ctl_lun_map_deinit(struct ctl_port *port)
{
        struct ctl_softc *softc = port->ctl_softc;
        struct ctl_lun *lun;

        if (port->lun_map == NULL)
                return (0);
        port->lun_map_size = 0;
        free(port->lun_map, M_CTL);
        port->lun_map = NULL;
        if (port->status & CTL_PORT_STATUS_ONLINE) {
                if (port->lun_enable != NULL) {
                        STAILQ_FOREACH(lun, &softc->lun_list, links)
                                port->lun_enable(port->targ_lun_arg, lun->lun);
                }
                ctl_isc_announce_port(port);
        }
        return (0);
}

int
ctl_lun_map_set(struct ctl_port *port, uint32_t plun, uint32_t glun)
{
        int status;
        uint32_t old;

        if (port->lun_map == NULL) {
                status = ctl_lun_map_init(port);
                if (status != 0)
                        return (status);
        }
        if (plun >= port->lun_map_size)
                return (EINVAL);
        old = port->lun_map[plun];
        port->lun_map[plun] = glun;
        if ((port->status & CTL_PORT_STATUS_ONLINE) && old == UINT32_MAX) {
                if (port->lun_enable != NULL)
                        port->lun_enable(port->targ_lun_arg, plun);
                ctl_isc_announce_port(port);
        }
        return (0);
}

int
ctl_lun_map_unset(struct ctl_port *port, uint32_t plun)
{
        uint32_t old;

        if (port->lun_map == NULL || plun >= port->lun_map_size)
                return (0);
        old = port->lun_map[plun];
        port->lun_map[plun] = UINT32_MAX;
        if ((port->status & CTL_PORT_STATUS_ONLINE) && old != UINT32_MAX) {
                if (port->lun_disable != NULL)
                        port->lun_disable(port->targ_lun_arg, plun);
                ctl_isc_announce_port(port);
        }
        return (0);
}

uint32_t
ctl_lun_map_from_port(struct ctl_port *port, uint32_t lun_id)
{

        if (port == NULL)
                return (UINT32_MAX);
        if (port->lun_map == NULL)
                return (lun_id);
        if (lun_id > port->lun_map_size)
                return (UINT32_MAX);
        return (port->lun_map[lun_id]);
}

uint32_t
ctl_lun_map_to_port(struct ctl_port *port, uint32_t lun_id)
{
        uint32_t i;

        if (port == NULL)
                return (UINT32_MAX);
        if (port->lun_map == NULL)
                return (lun_id);
        for (i = 0; i < port->lun_map_size; i++) {
                if (port->lun_map[i] == lun_id)
                        return (i);
        }
        return (UINT32_MAX);
}

uint32_t
ctl_decode_lun(uint64_t encoded)
{
        uint8_t lun[8];
        uint32_t result = 0xffffffff;

        be64enc(lun, encoded);
        switch (lun[0] & RPL_LUNDATA_ATYP_MASK) {
        case RPL_LUNDATA_ATYP_PERIPH:
                if ((lun[0] & 0x3f) == 0 && lun[2] == 0 && lun[3] == 0 &&
                    lun[4] == 0 && lun[5] == 0 && lun[6] == 0 && lun[7] == 0)
                        result = lun[1];
                break;
        case RPL_LUNDATA_ATYP_FLAT:
                if (lun[2] == 0 && lun[3] == 0 && lun[4] == 0 && lun[5] == 0 &&
                    lun[6] == 0 && lun[7] == 0)
                        result = ((lun[0] & 0x3f) << 8) + lun[1];
                break;
        case RPL_LUNDATA_ATYP_EXTLUN:
                switch (lun[0] & RPL_LUNDATA_EXT_EAM_MASK) {
                case 0x02:
                        switch (lun[0] & RPL_LUNDATA_EXT_LEN_MASK) {
                        case 0x00:
                                result = lun[1];
                                break;
                        case 0x10:
                                result = (lun[1] << 16) + (lun[2] << 8) +
                                    lun[3];
                                break;
                        case 0x20:
                                if (lun[1] == 0 && lun[6] == 0 && lun[7] == 0)
                                        result = (lun[2] << 24) +
                                            (lun[3] << 16) + (lun[4] << 8) +
                                            lun[5];
                                break;
                        }
                        break;
                case RPL_LUNDATA_EXT_EAM_NOT_SPEC:
                        result = 0xffffffff;
                        break;
                }
                break;
        }
        return (result);
}

uint64_t
ctl_encode_lun(uint32_t decoded)
{
        uint64_t l = decoded;

        if (l <= 0xff)
                return (((uint64_t)RPL_LUNDATA_ATYP_PERIPH << 56) | (l << 48));
        if (l <= 0x3fff)
                return (((uint64_t)RPL_LUNDATA_ATYP_FLAT << 56) | (l << 48));
        if (l <= 0xffffff)
                return (((uint64_t)(RPL_LUNDATA_ATYP_EXTLUN | 0x12) << 56) |
                    (l << 32));
        return ((((uint64_t)RPL_LUNDATA_ATYP_EXTLUN | 0x22) << 56) | (l << 16));
}

int
ctl_ffz(uint32_t *mask, uint32_t first, uint32_t last)
{
        int i;

        for (i = first; i < last; i++) {
                if ((mask[i / 32] & (1 << (i % 32))) == 0)
                        return (i);
        }
        return (-1);
}

int
ctl_set_mask(uint32_t *mask, uint32_t bit)
{
        uint32_t chunk, piece;

        chunk = bit >> 5;
        piece = bit % (sizeof(uint32_t) * 8);

        if ((mask[chunk] & (1 << piece)) != 0)
                return (-1);
        else
                mask[chunk] |= (1 << piece);

        return (0);
}

int
ctl_clear_mask(uint32_t *mask, uint32_t bit)
{
        uint32_t chunk, piece;

        chunk = bit >> 5;
        piece = bit % (sizeof(uint32_t) * 8);

        if ((mask[chunk] & (1 << piece)) == 0)
                return (-1);
        else
                mask[chunk] &= ~(1 << piece);

        return (0);
}

int
ctl_is_set(uint32_t *mask, uint32_t bit)
{
        uint32_t chunk, piece;

        chunk = bit >> 5;
        piece = bit % (sizeof(uint32_t) * 8);

        if ((mask[chunk] & (1 << piece)) == 0)
                return (0);
        else
                return (1);
}

static uint64_t
ctl_get_prkey(struct ctl_lun *lun, uint32_t residx)
{
        uint64_t *t;

        t = lun->pr_keys[residx/CTL_MAX_INIT_PER_PORT];
        if (t == NULL)
                return (0);
        return (t[residx % CTL_MAX_INIT_PER_PORT]);
}

static void
ctl_clr_prkey(struct ctl_lun *lun, uint32_t residx)
{
        uint64_t *t;

        t = lun->pr_keys[residx/CTL_MAX_INIT_PER_PORT];
        if (t == NULL)
                return;
        t[residx % CTL_MAX_INIT_PER_PORT] = 0;
}

static void
ctl_alloc_prkey(struct ctl_lun *lun, uint32_t residx)
{
        uint64_t *p;
        u_int i;

        i = residx/CTL_MAX_INIT_PER_PORT;
        if (lun->pr_keys[i] != NULL)
                return;
        mtx_unlock(&lun->lun_lock);
        p = malloc(sizeof(uint64_t) * CTL_MAX_INIT_PER_PORT, M_CTL,
            M_WAITOK | M_ZERO);
        mtx_lock(&lun->lun_lock);
        if (lun->pr_keys[i] == NULL)
                lun->pr_keys[i] = p;
        else
                free(p, M_CTL);
}

static void
ctl_set_prkey(struct ctl_lun *lun, uint32_t residx, uint64_t key)
{
        uint64_t *t;

        t = lun->pr_keys[residx/CTL_MAX_INIT_PER_PORT];
        KASSERT(t != NULL, ("prkey %d is not allocated", residx));
        t[residx % CTL_MAX_INIT_PER_PORT] = key;
}

/*
 * ctl_softc, pool_name, total_ctl_io are passed in.
 * npool is passed out.
 */
int
ctl_pool_create(struct ctl_softc *ctl_softc, const char *pool_name,
                uint32_t total_ctl_io, void **npool)
{
        struct ctl_io_pool *pool;

        pool = (struct ctl_io_pool *)malloc(sizeof(*pool), M_CTL,
                                            M_NOWAIT | M_ZERO);
        if (pool == NULL)
                return (ENOMEM);

        snprintf(pool->name, sizeof(pool->name), "CTL IO %s", pool_name);
        pool->ctl_softc = ctl_softc;
#ifdef IO_POOLS
        pool->zone = uma_zsecond_create(pool->name, NULL,
            NULL, NULL, NULL, ctl_softc->io_zone);
        /* uma_prealloc(pool->zone, total_ctl_io); */
#else
        pool->zone = ctl_softc->io_zone;
#endif

        *npool = pool;
        return (0);
}

void
ctl_pool_free(struct ctl_io_pool *pool)
{

        if (pool == NULL)
                return;

#ifdef IO_POOLS
        uma_zdestroy(pool->zone);
#endif
        free(pool, M_CTL);
}

union ctl_io *
ctl_alloc_io(void *pool_ref)
{
        struct ctl_io_pool *pool = (struct ctl_io_pool *)pool_ref;
        union ctl_io *io;

        io = uma_zalloc(pool->zone, M_WAITOK);
        if (io != NULL) {
                io->io_hdr.pool = pool_ref;
                CTL_SOFTC(io) = pool->ctl_softc;
                TAILQ_INIT(&io->io_hdr.blocked_queue);
        }
        return (io);
}

union ctl_io *
ctl_alloc_io_nowait(void *pool_ref)
{
        struct ctl_io_pool *pool = (struct ctl_io_pool *)pool_ref;
        union ctl_io *io;

        io = uma_zalloc(pool->zone, M_NOWAIT);
        if (io != NULL) {
                io->io_hdr.pool = pool_ref;
                CTL_SOFTC(io) = pool->ctl_softc;
                TAILQ_INIT(&io->io_hdr.blocked_queue);
        }
        return (io);
}

void
ctl_free_io(union ctl_io *io)
{
        struct ctl_io_pool *pool;

        if (io == NULL)
                return;

        pool = (struct ctl_io_pool *)io->io_hdr.pool;
        uma_zfree(pool->zone, io);
}

void
ctl_zero_io(union ctl_io *io)
{
        struct ctl_io_pool *pool;

        if (io == NULL)
                return;

        /*
         * May need to preserve linked list pointers at some point too.
         */
        pool = io->io_hdr.pool;
        memset(io, 0, sizeof(*io));
        io->io_hdr.pool = pool;
        CTL_SOFTC(io) = pool->ctl_softc;
        TAILQ_INIT(&io->io_hdr.blocked_queue);
}

int
ctl_expand_number(const char *buf, uint64_t *num)
{
        char *endptr;
        uint64_t number;
        unsigned shift;

        number = strtoq(buf, &endptr, 0);

        switch (tolower((unsigned char)*endptr)) {
        case 'e':
                shift = 60;
                break;
        case 'p':
                shift = 50;
                break;
        case 't':
                shift = 40;
                break;
        case 'g':
                shift = 30;
                break;
        case 'm':
                shift = 20;
                break;
        case 'k':
                shift = 10;
                break;
        case 'b':
        case '\0': /* No unit. */
                *num = number;
                return (0);
        default:
                /* Unrecognized unit. */
                return (-1);
        }

        if ((number << shift) >> shift != number) {
                /* Overflow */
                return (-1);
        }
        *num = number << shift;
        return (0);
}


/*
 * This routine could be used in the future to load default and/or saved
 * mode page parameters for a particuar lun.
 */
static int
ctl_init_page_index(struct ctl_lun *lun)
{
        int i, page_code;
        struct ctl_page_index *page_index;
        const char *value;
        uint64_t ival;

        memcpy(&lun->mode_pages.index, page_index_template,
               sizeof(page_index_template));

        for (i = 0; i < CTL_NUM_MODE_PAGES; i++) {

                page_index = &lun->mode_pages.index[i];
                if (lun->be_lun->lun_type == T_DIRECT &&
                    (page_index->page_flags & CTL_PAGE_FLAG_DIRECT) == 0)
                        continue;
                if (lun->be_lun->lun_type == T_PROCESSOR &&
                    (page_index->page_flags & CTL_PAGE_FLAG_PROC) == 0)
                        continue;
                if (lun->be_lun->lun_type == T_CDROM &&
                    (page_index->page_flags & CTL_PAGE_FLAG_CDROM) == 0)
                        continue;

                page_code = page_index->page_code & SMPH_PC_MASK;
                switch (page_code) {
                case SMS_RW_ERROR_RECOVERY_PAGE: {
                        KASSERT(page_index->subpage == SMS_SUBPAGE_PAGE_0,
                            ("subpage %#x for page %#x is incorrect!",
                            page_index->subpage, page_code));
                        memcpy(&lun->mode_pages.rw_er_page[CTL_PAGE_CURRENT],
                               &rw_er_page_default,
                               sizeof(rw_er_page_default));
                        memcpy(&lun->mode_pages.rw_er_page[CTL_PAGE_CHANGEABLE],
                               &rw_er_page_changeable,
                               sizeof(rw_er_page_changeable));
                        memcpy(&lun->mode_pages.rw_er_page[CTL_PAGE_DEFAULT],
                               &rw_er_page_default,
                               sizeof(rw_er_page_default));
                        memcpy(&lun->mode_pages.rw_er_page[CTL_PAGE_SAVED],
                               &rw_er_page_default,
                               sizeof(rw_er_page_default));
                        page_index->page_data =
                                (uint8_t *)lun->mode_pages.rw_er_page;
                        break;
                }
                case SMS_FORMAT_DEVICE_PAGE: {
                        struct scsi_format_page *format_page;

                        KASSERT(page_index->subpage == SMS_SUBPAGE_PAGE_0,
                            ("subpage %#x for page %#x is incorrect!",
                            page_index->subpage, page_code));

                        /*
                         * Sectors per track are set above.  Bytes per
                         * sector need to be set here on a per-LUN basis.
                         */
                        memcpy(&lun->mode_pages.format_page[CTL_PAGE_CURRENT],
                               &format_page_default,
                               sizeof(format_page_default));
                        memcpy(&lun->mode_pages.format_page[
                               CTL_PAGE_CHANGEABLE], &format_page_changeable,
                               sizeof(format_page_changeable));
                        memcpy(&lun->mode_pages.format_page[CTL_PAGE_DEFAULT],
                               &format_page_default,
                               sizeof(format_page_default));
                        memcpy(&lun->mode_pages.format_page[CTL_PAGE_SAVED],
                               &format_page_default,
                               sizeof(format_page_default));

                        format_page = &lun->mode_pages.format_page[
                                CTL_PAGE_CURRENT];
                        scsi_ulto2b(lun->be_lun->blocksize,
                                    format_page->bytes_per_sector);

                        format_page = &lun->mode_pages.format_page[
                                CTL_PAGE_DEFAULT];
                        scsi_ulto2b(lun->be_lun->blocksize,
                                    format_page->bytes_per_sector);

                        format_page = &lun->mode_pages.format_page[
                                CTL_PAGE_SAVED];
                        scsi_ulto2b(lun->be_lun->blocksize,
                                    format_page->bytes_per_sector);

                        page_index->page_data =
                                (uint8_t *)lun->mode_pages.format_page;
                        break;
                }
                case SMS_RIGID_DISK_PAGE: {
                        struct scsi_rigid_disk_page *rigid_disk_page;
                        uint32_t sectors_per_cylinder;
                        uint64_t cylinders;
#ifndef __XSCALE__
                        int shift;
#endif /* !__XSCALE__ */

                        KASSERT(page_index->subpage == SMS_SUBPAGE_PAGE_0,
                            ("subpage %#x for page %#x is incorrect!",
                            page_index->subpage, page_code));

                        /*
                         * Rotation rate and sectors per track are set
                         * above.  We calculate the cylinders here based on
                         * capacity.  Due to the number of heads and
                         * sectors per track we're using, smaller arrays
                         * may turn out to have 0 cylinders.  Linux and
                         * FreeBSD don't pay attention to these mode pages
                         * to figure out capacity, but Solaris does.  It
                         * seems to deal with 0 cylinders just fine, and
                         * works out a fake geometry based on the capacity.
                         */
                        memcpy(&lun->mode_pages.rigid_disk_page[
                               CTL_PAGE_DEFAULT], &rigid_disk_page_default,
                               sizeof(rigid_disk_page_default));
                        memcpy(&lun->mode_pages.rigid_disk_page[
                               CTL_PAGE_CHANGEABLE],&rigid_disk_page_changeable,
                               sizeof(rigid_disk_page_changeable));

                        sectors_per_cylinder = CTL_DEFAULT_SECTORS_PER_TRACK *
                                CTL_DEFAULT_HEADS;

                        /*
                         * The divide method here will be more accurate,
                         * probably, but results in floating point being
                         * used in the kernel on i386 (__udivdi3()).  On the
                         * XScale, though, __udivdi3() is implemented in
                         * software.
                         *
                         * The shift method for cylinder calculation is
                         * accurate if sectors_per_cylinder is a power of
                         * 2.  Otherwise it might be slightly off -- you
                         * might have a bit of a truncation problem.
                         */
#ifdef  __XSCALE__
                        cylinders = (lun->be_lun->maxlba + 1) /
                                sectors_per_cylinder;
#else
                        for (shift = 31; shift > 0; shift--) {
                                if (sectors_per_cylinder & (1 << shift))
                                        break;
                        }
                        cylinders = (lun->be_lun->maxlba + 1) >> shift;
#endif

                        /*
                         * We've basically got 3 bytes, or 24 bits for the
                         * cylinder size in the mode page.  If we're over,
                         * just round down to 2^24.
                         */
                        if (cylinders > 0xffffff)
                                cylinders = 0xffffff;

                        rigid_disk_page = &lun->mode_pages.rigid_disk_page[
                                CTL_PAGE_DEFAULT];
                        scsi_ulto3b(cylinders, rigid_disk_page->cylinders);

                        if ((value = dnvlist_get_string(lun->be_lun->options,
                            "rpm", NULL)) != NULL) {
                                scsi_ulto2b(strtol(value, NULL, 0),
                                     rigid_disk_page->rotation_rate);
                        }

                        memcpy(&lun->mode_pages.rigid_disk_page[CTL_PAGE_CURRENT],
                               &lun->mode_pages.rigid_disk_page[CTL_PAGE_DEFAULT],
                               sizeof(rigid_disk_page_default));
                        memcpy(&lun->mode_pages.rigid_disk_page[CTL_PAGE_SAVED],
                               &lun->mode_pages.rigid_disk_page[CTL_PAGE_DEFAULT],
                               sizeof(rigid_disk_page_default));

                        page_index->page_data =
                                (uint8_t *)lun->mode_pages.rigid_disk_page;
                        break;
                }
                case SMS_VERIFY_ERROR_RECOVERY_PAGE: {
                        KASSERT(page_index->subpage == SMS_SUBPAGE_PAGE_0,
                            ("subpage %#x for page %#x is incorrect!",
                            page_index->subpage, page_code));
                        memcpy(&lun->mode_pages.verify_er_page[CTL_PAGE_CURRENT],
                               &verify_er_page_default,
                               sizeof(verify_er_page_default));
                        memcpy(&lun->mode_pages.verify_er_page[CTL_PAGE_CHANGEABLE],
                               &verify_er_page_changeable,
                               sizeof(verify_er_page_changeable));
                        memcpy(&lun->mode_pages.verify_er_page[CTL_PAGE_DEFAULT],
                               &verify_er_page_default,
                               sizeof(verify_er_page_default));
                        memcpy(&lun->mode_pages.verify_er_page[CTL_PAGE_SAVED],
                               &verify_er_page_default,
                               sizeof(verify_er_page_default));
                        page_index->page_data =
                                (uint8_t *)lun->mode_pages.verify_er_page;
                        break;
                }
                case SMS_CACHING_PAGE: {
                        struct scsi_caching_page *caching_page;

                        KASSERT(page_index->subpage == SMS_SUBPAGE_PAGE_0,
                            ("subpage %#x for page %#x is incorrect!",
                            page_index->subpage, page_code));
                        memcpy(&lun->mode_pages.caching_page[CTL_PAGE_DEFAULT],
                               &caching_page_default,
                               sizeof(caching_page_default));
                        memcpy(&lun->mode_pages.caching_page[
                               CTL_PAGE_CHANGEABLE], &caching_page_changeable,
                               sizeof(caching_page_changeable));
                        memcpy(&lun->mode_pages.caching_page[CTL_PAGE_SAVED],
                               &caching_page_default,
                               sizeof(caching_page_default));
                        caching_page = &lun->mode_pages.caching_page[
                            CTL_PAGE_SAVED];
                        value = dnvlist_get_string(lun->be_lun->options,
                            "writecache", NULL);
                        if (value != NULL && strcmp(value, "off") == 0)
                                caching_page->flags1 &= ~SCP_WCE;
                        value = dnvlist_get_string(lun->be_lun->options,
                            "readcache", NULL);
                        if (value != NULL && strcmp(value, "off") == 0)
                                caching_page->flags1 |= SCP_RCD;
                        memcpy(&lun->mode_pages.caching_page[CTL_PAGE_CURRENT],
                               &lun->mode_pages.caching_page[CTL_PAGE_SAVED],
                               sizeof(caching_page_default));
                        page_index->page_data =
                                (uint8_t *)lun->mode_pages.caching_page;
                        break;
                }
                case SMS_CONTROL_MODE_PAGE: {
                        switch (page_index->subpage) {
                        case SMS_SUBPAGE_PAGE_0: {
                                struct scsi_control_page *control_page;

                                memcpy(&lun->mode_pages.control_page[
                                    CTL_PAGE_DEFAULT],
                                       &control_page_default,
                                       sizeof(control_page_default));
                                memcpy(&lun->mode_pages.control_page[
                                    CTL_PAGE_CHANGEABLE],
                                       &control_page_changeable,
                                       sizeof(control_page_changeable));
                                memcpy(&lun->mode_pages.control_page[
                                    CTL_PAGE_SAVED],
                                       &control_page_default,
                                       sizeof(control_page_default));
                                control_page = &lun->mode_pages.control_page[
                                    CTL_PAGE_SAVED];
                                value = dnvlist_get_string(lun->be_lun->options,
                                    "reordering", NULL);
                                if (value != NULL &&
                                    strcmp(value, "unrestricted") == 0) {
                                        control_page->queue_flags &=
                                            ~SCP_QUEUE_ALG_MASK;
                                        control_page->queue_flags |=
                                            SCP_QUEUE_ALG_UNRESTRICTED;
                                }
                                memcpy(&lun->mode_pages.control_page[
                                    CTL_PAGE_CURRENT],
                                       &lun->mode_pages.control_page[
                                    CTL_PAGE_SAVED],
                                       sizeof(control_page_default));
                                page_index->page_data =
                                    (uint8_t *)lun->mode_pages.control_page;
                                break;
                        }
                        case 0x01:
                                memcpy(&lun->mode_pages.control_ext_page[
                                    CTL_PAGE_DEFAULT],
                                       &control_ext_page_default,
                                       sizeof(control_ext_page_default));
                                memcpy(&lun->mode_pages.control_ext_page[
                                    CTL_PAGE_CHANGEABLE],
                                       &control_ext_page_changeable,
                                       sizeof(control_ext_page_changeable));
                                memcpy(&lun->mode_pages.control_ext_page[
                                    CTL_PAGE_SAVED],
                                       &control_ext_page_default,
                                       sizeof(control_ext_page_default));
                                memcpy(&lun->mode_pages.control_ext_page[
                                    CTL_PAGE_CURRENT],
                                       &lun->mode_pages.control_ext_page[
                                    CTL_PAGE_SAVED],
                                       sizeof(control_ext_page_default));
                                page_index->page_data =
                                    (uint8_t *)lun->mode_pages.control_ext_page;
                                break;
                        default:
                                panic("subpage %#x for page %#x is incorrect!",
                                      page_index->subpage, page_code);
                        }
                        break;
                }
                case SMS_INFO_EXCEPTIONS_PAGE: {
                        switch (page_index->subpage) {
                        case SMS_SUBPAGE_PAGE_0:
                                memcpy(&lun->mode_pages.ie_page[CTL_PAGE_CURRENT],
                                       &ie_page_default,
                                       sizeof(ie_page_default));
                                memcpy(&lun->mode_pages.ie_page[
                                       CTL_PAGE_CHANGEABLE], &ie_page_changeable,
                                       sizeof(ie_page_changeable));
                                memcpy(&lun->mode_pages.ie_page[CTL_PAGE_DEFAULT],
                                       &ie_page_default,
                                       sizeof(ie_page_default));
                                memcpy(&lun->mode_pages.ie_page[CTL_PAGE_SAVED],
                                       &ie_page_default,
                                       sizeof(ie_page_default));
                                page_index->page_data =
                                        (uint8_t *)lun->mode_pages.ie_page;
                                break;
                        case 0x02: {
                                struct ctl_logical_block_provisioning_page *page;

                                memcpy(&lun->mode_pages.lbp_page[CTL_PAGE_DEFAULT],
                                       &lbp_page_default,
                                       sizeof(lbp_page_default));
                                memcpy(&lun->mode_pages.lbp_page[
                                       CTL_PAGE_CHANGEABLE], &lbp_page_changeable,
                                       sizeof(lbp_page_changeable));
                                memcpy(&lun->mode_pages.lbp_page[CTL_PAGE_SAVED],
                                       &lbp_page_default,
                                       sizeof(lbp_page_default));
                                page = &lun->mode_pages.lbp_page[CTL_PAGE_SAVED];
                                value = dnvlist_get_string(lun->be_lun->options,
                                    "avail-threshold", NULL);
                                if (value != NULL &&
                                    ctl_expand_number(value, &ival) == 0) {
                                        page->descr[0].flags |= SLBPPD_ENABLED |
                                            SLBPPD_ARMING_DEC;
                                        if (lun->be_lun->blocksize)
                                                ival /= lun->be_lun->blocksize;
                                        else
                                                ival /= 512;
                                        scsi_ulto4b(ival >> CTL_LBP_EXPONENT,
                                            page->descr[0].count);
                                }
                                value = dnvlist_get_string(lun->be_lun->options,
                                    "used-threshold", NULL);
                                if (value != NULL &&
                                    ctl_expand_number(value, &ival) == 0) {
                                        page->descr[1].flags |= SLBPPD_ENABLED |
                                            SLBPPD_ARMING_INC;
                                        if (lun->be_lun->blocksize)
                                                ival /= lun->be_lun->blocksize;
                                        else
                                                ival /= 512;
                                        scsi_ulto4b(ival >> CTL_LBP_EXPONENT,
                                            page->descr[1].count);
                                }
                                value = dnvlist_get_string(lun->be_lun->options,
                                    "pool-avail-threshold", NULL);
                                if (value != NULL &&
                                    ctl_expand_number(value, &ival) == 0) {
                                        page->descr[2].flags |= SLBPPD_ENABLED |
                                            SLBPPD_ARMING_DEC;
                                        if (lun->be_lun->blocksize)
                                                ival /= lun->be_lun->blocksize;
                                        else
                                                ival /= 512;
                                        scsi_ulto4b(ival >> CTL_LBP_EXPONENT,
                                            page->descr[2].count);
                                }
                                value = dnvlist_get_string(lun->be_lun->options,
                                    "pool-used-threshold", NULL);
                                if (value != NULL &&
                                    ctl_expand_number(value, &ival) == 0) {
                                        page->descr[3].flags |= SLBPPD_ENABLED |
                                            SLBPPD_ARMING_INC;
                                        if (lun->be_lun->blocksize)
                                                ival /= lun->be_lun->blocksize;
                                        else
                                                ival /= 512;
                                        scsi_ulto4b(ival >> CTL_LBP_EXPONENT,
                                            page->descr[3].count);
                                }
                                memcpy(&lun->mode_pages.lbp_page[CTL_PAGE_CURRENT],
                                       &lun->mode_pages.lbp_page[CTL_PAGE_SAVED],
                                       sizeof(lbp_page_default));
                                page_index->page_data =
                                        (uint8_t *)lun->mode_pages.lbp_page;
                                break;
                        }
                        default:
                                panic("subpage %#x for page %#x is incorrect!",
                                      page_index->subpage, page_code);
                        }
                        break;
                }
                case SMS_CDDVD_CAPS_PAGE:{
                        KASSERT(page_index->subpage == SMS_SUBPAGE_PAGE_0,
                            ("subpage %#x for page %#x is incorrect!",
                            page_index->subpage, page_code));
                        memcpy(&lun->mode_pages.cddvd_page[CTL_PAGE_DEFAULT],
                               &cddvd_page_default,
                               sizeof(cddvd_page_default));
                        memcpy(&lun->mode_pages.cddvd_page[
                               CTL_PAGE_CHANGEABLE], &cddvd_page_changeable,
                               sizeof(cddvd_page_changeable));
                        memcpy(&lun->mode_pages.cddvd_page[CTL_PAGE_SAVED],
                               &cddvd_page_default,
                               sizeof(cddvd_page_default));
                        memcpy(&lun->mode_pages.cddvd_page[CTL_PAGE_CURRENT],
                               &lun->mode_pages.cddvd_page[CTL_PAGE_SAVED],
                               sizeof(cddvd_page_default));
                        page_index->page_data =
                                (uint8_t *)lun->mode_pages.cddvd_page;
                        break;
                }
                default:
                        panic("invalid page code value %#x", page_code);
                }
        }

        return (CTL_RETVAL_COMPLETE);
}

static int
ctl_init_log_page_index(struct ctl_lun *lun)
{
        struct ctl_page_index *page_index;
        int i, j, k, prev;

        memcpy(&lun->log_pages.index, log_page_index_template,
               sizeof(log_page_index_template));

        prev = -1;
        for (i = 0, j = 0, k = 0; i < CTL_NUM_LOG_PAGES; i++) {

                page_index = &lun->log_pages.index[i];
                if (lun->be_lun->lun_type == T_DIRECT &&
                    (page_index->page_flags & CTL_PAGE_FLAG_DIRECT) == 0)
                        continue;
                if (lun->be_lun->lun_type == T_PROCESSOR &&
                    (page_index->page_flags & CTL_PAGE_FLAG_PROC) == 0)
                        continue;
                if (lun->be_lun->lun_type == T_CDROM &&
                    (page_index->page_flags & CTL_PAGE_FLAG_CDROM) == 0)
                        continue;

                if (page_index->page_code == SLS_LOGICAL_BLOCK_PROVISIONING &&
                    lun->backend->lun_attr == NULL)
                        continue;

                if (page_index->page_code != prev) {
                        lun->log_pages.pages_page[j] = page_index->page_code;
                        prev = page_index->page_code;
                        j++;
                }
                lun->log_pages.subpages_page[k*2] = page_index->page_code;
                lun->log_pages.subpages_page[k*2+1] = page_index->subpage;
                k++;
        }
        lun->log_pages.index[0].page_data = &lun->log_pages.pages_page[0];
        lun->log_pages.index[0].page_len = j;
        lun->log_pages.index[1].page_data = &lun->log_pages.subpages_page[0];
        lun->log_pages.index[1].page_len = k * 2;
        lun->log_pages.index[2].page_data = (uint8_t *)&lun->log_pages.temp_page;
        lun->log_pages.index[2].page_len = sizeof(lun->log_pages.temp_page);
        lun->log_pages.index[3].page_data = &lun->log_pages.lbp_page[0];
        lun->log_pages.index[3].page_len = 12*CTL_NUM_LBP_PARAMS;
        lun->log_pages.index[4].page_data = (uint8_t *)&lun->log_pages.stat_page;
        lun->log_pages.index[4].page_len = sizeof(lun->log_pages.stat_page);
        lun->log_pages.index[5].page_data = (uint8_t *)&lun->log_pages.ie_page;
        lun->log_pages.index[5].page_len = sizeof(lun->log_pages.ie_page);

        return (CTL_RETVAL_COMPLETE);
}

static int
hex2bin(const char *str, uint8_t *buf, int buf_size)
{
        int i;
        u_char c;

        memset(buf, 0, buf_size);
        while (isspace(str[0]))
                str++;
        if (str[0] == '0' && (str[1] == 'x' || str[1] == 'X'))
                str += 2;
        buf_size *= 2;
        for (i = 0; str[i] != 0 && i < buf_size; i++) {
                while (str[i] == '-')   /* Skip dashes in UUIDs. */
                        str++;
                c = str[i];
                if (isdigit(c))
                        c -= '0';
                else if (isalpha(c))
                        c -= isupper(c) ? 'A' - 10 : 'a' - 10;
                else
                        break;
                if (c >= 16)
                        break;
                if ((i & 1) == 0)
                        buf[i / 2] |= (c << 4);
                else
                        buf[i / 2] |= c;
        }
        return ((i + 1) / 2);
}

/*
 * Add LUN.
 *
 * Returns 0 for success, non-zero (errno) for failure.
 */
int
ctl_add_lun(struct ctl_be_lun *be_lun)
{
        struct ctl_softc *ctl_softc = control_softc;
        struct ctl_lun *nlun, *lun;
        struct scsi_vpd_id_descriptor *desc;
        struct scsi_vpd_id_t10 *t10id;
        const char *eui, *naa, *scsiname, *uuid, *vendor, *value;
        int lun_number;
        int devidlen, idlen1, idlen2 = 0, len;

        /*
         * We support only Direct Access, CD-ROM or Processor LUN types.
         */
        switch (be_lun->lun_type) {
        case T_DIRECT:
        case T_PROCESSOR:
        case T_CDROM:
                break;
        case T_SEQUENTIAL:
        case T_CHANGER:
        default:
                return (EINVAL);
        }
        lun = malloc(sizeof(*lun), M_CTL, M_WAITOK | M_ZERO);

        lun->pending_sense = malloc(sizeof(struct scsi_sense_data *) *
            ctl_max_ports, M_DEVBUF, M_WAITOK | M_ZERO);
        lun->pending_ua = malloc(sizeof(ctl_ua_type *) * ctl_max_ports,
            M_DEVBUF, M_WAITOK | M_ZERO);
        lun->pr_keys = malloc(sizeof(uint64_t *) * ctl_max_ports,
            M_DEVBUF, M_WAITOK | M_ZERO);

        /* Generate LUN ID. */
        devidlen = max(CTL_DEVID_MIN_LEN,
            strnlen(be_lun->device_id, CTL_DEVID_LEN));
        idlen1 = sizeof(*t10id) + devidlen;
        len = sizeof(struct scsi_vpd_id_descriptor) + idlen1;
        scsiname = dnvlist_get_string(be_lun->options, "scsiname", NULL);
        if (scsiname != NULL) {
                idlen2 = roundup2(strlen(scsiname) + 1, 4);
                len += sizeof(struct scsi_vpd_id_descriptor) + idlen2;
        }
        eui = dnvlist_get_string(be_lun->options, "eui", NULL);
        if (eui != NULL) {
                len += sizeof(struct scsi_vpd_id_descriptor) + 16;
        }
        naa = dnvlist_get_string(be_lun->options, "naa", NULL);
        if (naa != NULL) {
                len += sizeof(struct scsi_vpd_id_descriptor) + 16;
        }
        uuid = dnvlist_get_string(be_lun->options, "uuid", NULL);
        if (uuid != NULL) {
                len += sizeof(struct scsi_vpd_id_descriptor) + 18;
        }
        lun->lun_devid = malloc(sizeof(struct ctl_devid) + len,
            M_CTL, M_WAITOK | M_ZERO);
        desc = (struct scsi_vpd_id_descriptor *)lun->lun_devid->data;
        desc->proto_codeset = SVPD_ID_CODESET_ASCII;
        desc->id_type = SVPD_ID_PIV | SVPD_ID_ASSOC_LUN | SVPD_ID_TYPE_T10;
        desc->length = idlen1;
        t10id = (struct scsi_vpd_id_t10 *)&desc->identifier[0];
        memset(t10id->vendor, ' ', sizeof(t10id->vendor));
        if ((vendor = dnvlist_get_string(be_lun->options, "vendor", NULL)) == NULL) {
                strncpy((char *)t10id->vendor, CTL_VENDOR, sizeof(t10id->vendor));
        } else {
                strncpy(t10id->vendor, vendor,
                    min(sizeof(t10id->vendor), strlen(vendor)));
        }
        strncpy((char *)t10id->vendor_spec_id,
            (char *)be_lun->device_id, devidlen);
        if (scsiname != NULL) {
                desc = (struct scsi_vpd_id_descriptor *)(&desc->identifier[0] +
                    desc->length);
                desc->proto_codeset = SVPD_ID_CODESET_UTF8;
                desc->id_type = SVPD_ID_PIV | SVPD_ID_ASSOC_LUN |
                    SVPD_ID_TYPE_SCSI_NAME;
                desc->length = idlen2;
                strlcpy(desc->identifier, scsiname, idlen2);
        }
        if (eui != NULL) {
                desc = (struct scsi_vpd_id_descriptor *)(&desc->identifier[0] +
                    desc->length);
                desc->proto_codeset = SVPD_ID_CODESET_BINARY;
                desc->id_type = SVPD_ID_PIV | SVPD_ID_ASSOC_LUN |
                    SVPD_ID_TYPE_EUI64;
                desc->length = hex2bin(eui, desc->identifier, 16);
                desc->length = desc->length > 12 ? 16 :
                    (desc->length > 8 ? 12 : 8);
                len -= 16 - desc->length;
        }
        if (naa != NULL) {
                desc = (struct scsi_vpd_id_descriptor *)(&desc->identifier[0] +
                    desc->length);
                desc->proto_codeset = SVPD_ID_CODESET_BINARY;
                desc->id_type = SVPD_ID_PIV | SVPD_ID_ASSOC_LUN |
                    SVPD_ID_TYPE_NAA;
                desc->length = hex2bin(naa, desc->identifier, 16);
                desc->length = desc->length > 8 ? 16 : 8;
                len -= 16 - desc->length;
        }
        if (uuid != NULL) {
                desc = (struct scsi_vpd_id_descriptor *)(&desc->identifier[0] +
                    desc->length);
                desc->proto_codeset = SVPD_ID_CODESET_BINARY;
                desc->id_type = SVPD_ID_PIV | SVPD_ID_ASSOC_LUN |
                    SVPD_ID_TYPE_UUID;
                desc->identifier[0] = 0x10;
                hex2bin(uuid, &desc->identifier[2], 16);
                desc->length = 18;
        }
        lun->lun_devid->len = len;

        mtx_lock(&ctl_softc->ctl_lock);
        /*
         * See if the caller requested a particular LUN number.  If so, see
         * if it is available.  Otherwise, allocate the first available LUN.
         */
        if (be_lun->flags & CTL_LUN_FLAG_ID_REQ) {
                if ((be_lun->req_lun_id > (ctl_max_luns - 1))
                 || (ctl_is_set(ctl_softc->ctl_lun_mask, be_lun->req_lun_id))) {
                        mtx_unlock(&ctl_softc->ctl_lock);
                        if (be_lun->req_lun_id > (ctl_max_luns - 1)) {
                                printf("ctl: requested LUN ID %d is higher "
                                       "than ctl_max_luns - 1 (%d)\n",
                                       be_lun->req_lun_id, ctl_max_luns - 1);
                        } else {
                                /*
                                 * XXX KDM return an error, or just assign
                                 * another LUN ID in this case??
                                 */
                                printf("ctl: requested LUN ID %d is already "
                                       "in use\n", be_lun->req_lun_id);
                        }
fail:
                        free(lun->lun_devid, M_CTL);
                        free(lun, M_CTL);
                        return (ENOSPC);
                }
                lun_number = be_lun->req_lun_id;
        } else {
                lun_number = ctl_ffz(ctl_softc->ctl_lun_mask, 0, ctl_max_luns);
                if (lun_number == -1) {
                        mtx_unlock(&ctl_softc->ctl_lock);
                        printf("ctl: can't allocate LUN, out of LUNs\n");
                        goto fail;
                }
        }
        ctl_set_mask(ctl_softc->ctl_lun_mask, lun_number);
        mtx_unlock(&ctl_softc->ctl_lock);

        mtx_init(&lun->lun_lock, "CTL LUN", NULL, MTX_DEF);
        lun->lun = lun_number;
        lun->be_lun = be_lun;
        /*
         * The processor LUN is always enabled.  Disk LUNs come on line
         * disabled, and must be enabled by the backend.
         */
        lun->flags |= CTL_LUN_DISABLED;
        lun->backend = be_lun->be;
        be_lun->ctl_lun = lun;
        be_lun->lun_id = lun_number;
        if (be_lun->flags & CTL_LUN_FLAG_EJECTED)
                lun->flags |= CTL_LUN_EJECTED;
        if (be_lun->flags & CTL_LUN_FLAG_NO_MEDIA)
                lun->flags |= CTL_LUN_NO_MEDIA;
        if (be_lun->flags & CTL_LUN_FLAG_STOPPED)
                lun->flags |= CTL_LUN_STOPPED;

        if (be_lun->flags & CTL_LUN_FLAG_PRIMARY)
                lun->flags |= CTL_LUN_PRIMARY_SC;

        value = dnvlist_get_string(be_lun->options, "removable", NULL);
        if (value != NULL) {
                if (strcmp(value, "on") == 0)
                        lun->flags |= CTL_LUN_REMOVABLE;
        } else if (be_lun->lun_type == T_CDROM)
                lun->flags |= CTL_LUN_REMOVABLE;

        lun->ctl_softc = ctl_softc;
#ifdef CTL_TIME_IO
        lun->last_busy = getsbinuptime();
#endif
        TAILQ_INIT(&lun->ooa_queue);
        STAILQ_INIT(&lun->error_list);
        lun->ie_reported = 1;
        callout_init_mtx(&lun->ie_callout, &lun->lun_lock, 0);
        ctl_tpc_lun_init(lun);
        if (lun->flags & CTL_LUN_REMOVABLE) {
                lun->prevent = malloc((CTL_MAX_INITIATORS + 31) / 32 * 4,
                    M_CTL, M_WAITOK);
        }

        /*
         * Initialize the mode and log page index.
         */
        ctl_init_page_index(lun);
        ctl_init_log_page_index(lun);

        /* Setup statistics gathering */
        lun->stats.item = lun_number;

        /*
         * Now, before we insert this lun on the lun list, set the lun
         * inventory changed UA for all other luns.
         */
        mtx_lock(&ctl_softc->ctl_lock);
        STAILQ_FOREACH(nlun, &ctl_softc->lun_list, links) {
                mtx_lock(&nlun->lun_lock);
                ctl_est_ua_all(nlun, -1, CTL_UA_LUN_CHANGE);
                mtx_unlock(&nlun->lun_lock);
        }
        STAILQ_INSERT_TAIL(&ctl_softc->lun_list, lun, links);
        ctl_softc->ctl_luns[lun_number] = lun;
        ctl_softc->num_luns++;
        mtx_unlock(&ctl_softc->ctl_lock);

        /*
         * We successfully added the LUN, attempt to enable it.
         */
        if (ctl_enable_lun(lun) != 0) {
                printf("%s: ctl_enable_lun() failed!\n", __func__);
                mtx_lock(&ctl_softc->ctl_lock);
                STAILQ_REMOVE(&ctl_softc->lun_list, lun, ctl_lun, links);
                ctl_clear_mask(ctl_softc->ctl_lun_mask, lun_number);
                ctl_softc->ctl_luns[lun_number] = NULL;
                ctl_softc->num_luns--;
                mtx_unlock(&ctl_softc->ctl_lock);
                free(lun->lun_devid, M_CTL);
                free(lun, M_CTL);
                return (EIO);
        }

        return (0);
}

/*
 * Free LUN that has no active requests.
 */
static int
ctl_free_lun(struct ctl_lun *lun)
{
        struct ctl_softc *softc = lun->ctl_softc;
        struct ctl_lun *nlun;
        int i;

        KASSERT(TAILQ_EMPTY(&lun->ooa_queue),
            ("Freeing a LUN %p with outstanding I/O!\n", lun));

        mtx_lock(&softc->ctl_lock);
        STAILQ_REMOVE(&softc->lun_list, lun, ctl_lun, links);
        ctl_clear_mask(softc->ctl_lun_mask, lun->lun);
        softc->ctl_luns[lun->lun] = NULL;
        softc->num_luns--;
        STAILQ_FOREACH(nlun, &softc->lun_list, links) {
                mtx_lock(&nlun->lun_lock);
                ctl_est_ua_all(nlun, -1, CTL_UA_LUN_CHANGE);
                mtx_unlock(&nlun->lun_lock);
        }
        mtx_unlock(&softc->ctl_lock);

        /*
         * Tell the backend to free resources, if this LUN has a backend.
         */
        lun->be_lun->lun_shutdown(lun->be_lun);

        lun->ie_reportcnt = UINT32_MAX;
        callout_drain(&lun->ie_callout);
        ctl_tpc_lun_shutdown(lun);
        mtx_destroy(&lun->lun_lock);
        free(lun->lun_devid, M_CTL);
        for (i = 0; i < ctl_max_ports; i++)
                free(lun->pending_ua[i], M_CTL);
        free(lun->pending_ua, M_DEVBUF);
        for (i = 0; i < ctl_max_ports; i++)
                free(lun->pr_keys[i], M_CTL);
        free(lun->pr_keys, M_DEVBUF);
        free(lun->write_buffer, M_CTL);
        free(lun->prevent, M_CTL);
        free(lun, M_CTL);

        return (0);
}

static int
ctl_enable_lun(struct ctl_lun *lun)
{
        struct ctl_softc *softc;
        struct ctl_port *port, *nport;
        int retval;

        softc = lun->ctl_softc;

        mtx_lock(&softc->ctl_lock);
        mtx_lock(&lun->lun_lock);
        KASSERT((lun->flags & CTL_LUN_DISABLED) != 0,
            ("%s: LUN not disabled", __func__));
        lun->flags &= ~CTL_LUN_DISABLED;
        mtx_unlock(&lun->lun_lock);

        STAILQ_FOREACH_SAFE(port, &softc->port_list, links, nport) {
                if ((port->status & CTL_PORT_STATUS_ONLINE) == 0 ||
                    port->lun_map != NULL || port->lun_enable == NULL)
                        continue;

                /*
                 * Drop the lock while we call the FETD's enable routine.
                 * This can lead to a callback into CTL (at least in the
                 * case of the internal initiator frontend.
                 */
                mtx_unlock(&softc->ctl_lock);
                retval = port->lun_enable(port->targ_lun_arg, lun->lun);
                mtx_lock(&softc->ctl_lock);
                if (retval != 0) {
                        printf("%s: FETD %s port %d returned error "
                               "%d for lun_enable on lun %jd\n",
                               __func__, port->port_name, port->targ_port,
                               retval, (intmax_t)lun->lun);
                }
        }

        mtx_unlock(&softc->ctl_lock);
        ctl_isc_announce_lun(lun);

        return (0);
}

static int
ctl_disable_lun(struct ctl_lun *lun)
{
        struct ctl_softc *softc;
        struct ctl_port *port;
        int retval;

        softc = lun->ctl_softc;

        mtx_lock(&softc->ctl_lock);
        mtx_lock(&lun->lun_lock);
        KASSERT((lun->flags & CTL_LUN_DISABLED) == 0,
            ("%s: LUN not enabled", __func__));
        lun->flags |= CTL_LUN_DISABLED;
        mtx_unlock(&lun->lun_lock);

        STAILQ_FOREACH(port, &softc->port_list, links) {
                if ((port->status & CTL_PORT_STATUS_ONLINE) == 0 ||
                    port->lun_map != NULL || port->lun_disable == NULL)
                        continue;

                /*
                 * Drop the lock before we call the frontend's disable
                 * routine, to avoid lock order reversals.
                 *
                 * XXX KDM what happens if the frontend list changes while
                 * we're traversing it?  It's unlikely, but should be handled.
                 */
                mtx_unlock(&softc->ctl_lock);
                retval = port->lun_disable(port->targ_lun_arg, lun->lun);
                mtx_lock(&softc->ctl_lock);
                if (retval != 0) {
                        printf("%s: FETD %s port %d returned error "
                               "%d for lun_disable on lun %jd\n",
                               __func__, port->port_name, port->targ_port,
                               retval, (intmax_t)lun->lun);
                }
        }

        mtx_unlock(&softc->ctl_lock);
        ctl_isc_announce_lun(lun);

        return (0);
}

int
ctl_start_lun(struct ctl_be_lun *be_lun)
{
        struct ctl_lun *lun = (struct ctl_lun *)be_lun->ctl_lun;

        mtx_lock(&lun->lun_lock);
        lun->flags &= ~CTL_LUN_STOPPED;
        mtx_unlock(&lun->lun_lock);
        return (0);
}

int
ctl_stop_lun(struct ctl_be_lun *be_lun)
{
        struct ctl_lun *lun = (struct ctl_lun *)be_lun->ctl_lun;

        mtx_lock(&lun->lun_lock);
        lun->flags |= CTL_LUN_STOPPED;
        mtx_unlock(&lun->lun_lock);
        return (0);
}

int
ctl_lun_no_media(struct ctl_be_lun *be_lun)
{
        struct ctl_lun *lun = (struct ctl_lun *)be_lun->ctl_lun;

        mtx_lock(&lun->lun_lock);
        lun->flags |= CTL_LUN_NO_MEDIA;
        mtx_unlock(&lun->lun_lock);
        return (0);
}

int
ctl_lun_has_media(struct ctl_be_lun *be_lun)
{
        struct ctl_lun *lun = (struct ctl_lun *)be_lun->ctl_lun;
        union ctl_ha_msg msg;

        mtx_lock(&lun->lun_lock);
        lun->flags &= ~(CTL_LUN_NO_MEDIA | CTL_LUN_EJECTED);
        if (lun->flags & CTL_LUN_REMOVABLE)
                ctl_est_ua_all(lun, -1, CTL_UA_MEDIUM_CHANGE);
        mtx_unlock(&lun->lun_lock);
        if ((lun->flags & CTL_LUN_REMOVABLE) &&
            lun->ctl_softc->ha_mode == CTL_HA_MODE_XFER) {
                bzero(&msg.ua, sizeof(msg.ua));
                msg.hdr.msg_type = CTL_MSG_UA;
                msg.hdr.nexus.initid = -1;
                msg.hdr.nexus.targ_port = -1;
                msg.hdr.nexus.targ_lun = lun->lun;
                msg.hdr.nexus.targ_mapped_lun = lun->lun;
                msg.ua.ua_all = 1;
                msg.ua.ua_set = 1;
                msg.ua.ua_type = CTL_UA_MEDIUM_CHANGE;
                ctl_ha_msg_send(CTL_HA_CHAN_CTL, &msg, sizeof(msg.ua),
                    M_WAITOK);
        }
        return (0);
}

int
ctl_lun_ejected(struct ctl_be_lun *be_lun)
{
        struct ctl_lun *lun = (struct ctl_lun *)be_lun->ctl_lun;

        mtx_lock(&lun->lun_lock);
        lun->flags |= CTL_LUN_EJECTED;
        mtx_unlock(&lun->lun_lock);
        return (0);
}

int
ctl_lun_primary(struct ctl_be_lun *be_lun)
{
        struct ctl_lun *lun = (struct ctl_lun *)be_lun->ctl_lun;

        mtx_lock(&lun->lun_lock);
        lun->flags |= CTL_LUN_PRIMARY_SC;
        ctl_est_ua_all(lun, -1, CTL_UA_ASYM_ACC_CHANGE);
        mtx_unlock(&lun->lun_lock);
        ctl_isc_announce_lun(lun);
        return (0);
}

int
ctl_lun_secondary(struct ctl_be_lun *be_lun)
{
        struct ctl_lun *lun = (struct ctl_lun *)be_lun->ctl_lun;

        mtx_lock(&lun->lun_lock);
        lun->flags &= ~CTL_LUN_PRIMARY_SC;
        ctl_est_ua_all(lun, -1, CTL_UA_ASYM_ACC_CHANGE);
        mtx_unlock(&lun->lun_lock);
        ctl_isc_announce_lun(lun);
        return (0);
}

/*
 * Remove LUN.  If there are active requests, wait for completion.
 *
 * Returns 0 for success, non-zero (errno) for failure.
 * Completion is reported to backed via the lun_shutdown() method.
 */
int
ctl_remove_lun(struct ctl_be_lun *be_lun)
{
        struct ctl_lun *lun;

        lun = (struct ctl_lun *)be_lun->ctl_lun;

        ctl_disable_lun(lun);

        mtx_lock(&lun->lun_lock);
        lun->flags |= CTL_LUN_INVALID;

        /*
         * If there is nothing in the OOA queue, go ahead and free the LUN.
         * If we have something in the OOA queue, we'll free it when the
         * last I/O completes.
         */
        if (TAILQ_EMPTY(&lun->ooa_queue)) {
                mtx_unlock(&lun->lun_lock);
                ctl_free_lun(lun);
        } else
                mtx_unlock(&lun->lun_lock);

        return (0);
}

void
ctl_lun_capacity_changed(struct ctl_be_lun *be_lun)
{
        struct ctl_lun *lun = (struct ctl_lun *)be_lun->ctl_lun;
        union ctl_ha_msg msg;

        mtx_lock(&lun->lun_lock);
        ctl_est_ua_all(lun, -1, CTL_UA_CAPACITY_CHANGE);
        mtx_unlock(&lun->lun_lock);
        if (lun->ctl_softc->ha_mode == CTL_HA_MODE_XFER) {
                /* Send msg to other side. */
                bzero(&msg.ua, sizeof(msg.ua));
                msg.hdr.msg_type = CTL_MSG_UA;
                msg.hdr.nexus.initid = -1;
                msg.hdr.nexus.targ_port = -1;
                msg.hdr.nexus.targ_lun = lun->lun;
                msg.hdr.nexus.targ_mapped_lun = lun->lun;
                msg.ua.ua_all = 1;
                msg.ua.ua_set = 1;
                msg.ua.ua_type = CTL_UA_CAPACITY_CHANGE;
                ctl_ha_msg_send(CTL_HA_CHAN_CTL, &msg, sizeof(msg.ua),
                    M_WAITOK);
        }
}

/*
 * Backend "memory move is complete" callback for requests that never
 * make it down to say RAIDCore's configuration code.
 */
int
ctl_config_move_done(union ctl_io *io)
{
        int retval;

        CTL_DEBUG_PRINT(("ctl_config_move_done\n"));
        KASSERT(io->io_hdr.io_type == CTL_IO_SCSI,
            ("Config I/O type isn't CTL_IO_SCSI (%d)!", io->io_hdr.io_type));

        if ((io->io_hdr.port_status != 0) &&
            ((io->io_hdr.status & CTL_STATUS_MASK) == CTL_STATUS_NONE ||
             (io->io_hdr.status & CTL_STATUS_MASK) == CTL_SUCCESS)) {
                ctl_set_internal_failure(&io->scsiio, /*sks_valid*/ 1,
                    /*retry_count*/ io->io_hdr.port_status);
        } else if (io->scsiio.kern_data_resid != 0 &&
            (io->io_hdr.flags & CTL_FLAG_DATA_MASK) == CTL_FLAG_DATA_OUT &&
            ((io->io_hdr.status & CTL_STATUS_MASK) == CTL_STATUS_NONE ||
             (io->io_hdr.status & CTL_STATUS_MASK) == CTL_SUCCESS)) {
                ctl_set_invalid_field_ciu(&io->scsiio);
        }

        if (ctl_debug & CTL_DEBUG_CDB_DATA)
                ctl_data_print(io);
        if (((io->io_hdr.flags & CTL_FLAG_DATA_MASK) == CTL_FLAG_DATA_IN) ||
            ((io->io_hdr.status & CTL_STATUS_MASK) != CTL_STATUS_NONE &&
             (io->io_hdr.status & CTL_STATUS_MASK) != CTL_SUCCESS) ||
            ((io->io_hdr.flags & CTL_FLAG_ABORT) != 0)) {
                /*
                 * XXX KDM just assuming a single pointer here, and not a
                 * S/G list.  If we start using S/G lists for config data,
                 * we'll need to know how to clean them up here as well.
                 */
                if (io->io_hdr.flags & CTL_FLAG_ALLOCATED)
                        free(io->scsiio.kern_data_ptr, M_CTL);
                ctl_done(io);
                retval = CTL_RETVAL_COMPLETE;
        } else {
                /*
                 * XXX KDM now we need to continue data movement.  Some
                 * options:
                 * - call ctl_scsiio() again?  We don't do this for data
                 *   writes, because for those at least we know ahead of
                 *   time where the write will go and how long it is.  For
                 *   config writes, though, that information is largely
                 *   contained within the write itself, thus we need to
                 *   parse out the data again.
                 *
                 * - Call some other function once the data is in?
                 */

                /*
                 * XXX KDM call ctl_scsiio() again for now, and check flag
                 * bits to see whether we're allocated or not.
                 */
                retval = ctl_scsiio(&io->scsiio);
        }
        return (retval);
}

/*
 * This gets called by a backend driver when it is done with a
 * data_submit method.
 */
void
ctl_data_submit_done(union ctl_io *io)
{
        /*
         * If the IO_CONT flag is set, we need to call the supplied
         * function to continue processing the I/O, instead of completing
         * the I/O just yet.
         *
         * If there is an error, though, we don't want to keep processing.
         * Instead, just send status back to the initiator.
         */
        if ((io->io_hdr.flags & CTL_FLAG_IO_CONT) &&
            (io->io_hdr.flags & CTL_FLAG_ABORT) == 0 &&
            ((io->io_hdr.status & CTL_STATUS_MASK) == CTL_STATUS_NONE ||
             (io->io_hdr.status & CTL_STATUS_MASK) == CTL_SUCCESS)) {
                io->scsiio.io_cont(io);
                return;
        }
        ctl_done(io);
}

/*
 * This gets called by a backend driver when it is done with a
 * configuration write.
 */
void
ctl_config_write_done(union ctl_io *io)
{
        uint8_t *buf;

        /*
         * If the IO_CONT flag is set, we need to call the supplied
         * function to continue processing the I/O, instead of completing
         * the I/O just yet.
         *
         * If there is an error, though, we don't want to keep processing.
         * Instead, just send status back to the initiator.
         */
        if ((io->io_hdr.flags & CTL_FLAG_IO_CONT) &&
            (io->io_hdr.flags & CTL_FLAG_ABORT) == 0 &&
            ((io->io_hdr.status & CTL_STATUS_MASK) == CTL_STATUS_NONE ||
             (io->io_hdr.status & CTL_STATUS_MASK) == CTL_SUCCESS)) {
                io->scsiio.io_cont(io);
                return;
        }
        /*
         * Since a configuration write can be done for commands that actually
         * have data allocated, like write buffer, and commands that have
         * no data, like start/stop unit, we need to check here.
         */
        if (io->io_hdr.flags & CTL_FLAG_ALLOCATED)
                buf = io->scsiio.kern_data_ptr;
        else
                buf = NULL;
        ctl_done(io);
        if (buf)
                free(buf, M_CTL);
}

void
ctl_config_read_done(union ctl_io *io)
{
        uint8_t *buf;

        /*
         * If there is some error -- we are done, skip data transfer.
         */
        if ((io->io_hdr.flags & CTL_FLAG_ABORT) != 0 ||
            ((io->io_hdr.status & CTL_STATUS_MASK) != CTL_STATUS_NONE &&
             (io->io_hdr.status & CTL_STATUS_MASK) != CTL_SUCCESS)) {
                if (io->io_hdr.flags & CTL_FLAG_ALLOCATED)
                        buf = io->scsiio.kern_data_ptr;
                else
                        buf = NULL;
                ctl_done(io);
                if (buf)
                        free(buf, M_CTL);
                return;
        }

        /*
         * If the IO_CONT flag is set, we need to call the supplied
         * function to continue processing the I/O, instead of completing
         * the I/O just yet.
         */
        if (io->io_hdr.flags & CTL_FLAG_IO_CONT) {
                io->scsiio.io_cont(io);
                return;
        }

        ctl_datamove(io);
}

/*
 * SCSI release command.
 */
int
ctl_scsi_release(struct ctl_scsiio *ctsio)
{
        struct ctl_lun *lun = CTL_LUN(ctsio);
        uint32_t residx;

        CTL_DEBUG_PRINT(("ctl_scsi_release\n"));

        residx = ctl_get_initindex(&ctsio->io_hdr.nexus);

        /*
         * XXX KDM right now, we only support LUN reservation.  We don't
         * support 3rd party reservations, or extent reservations, which
         * might actually need the parameter list.  If we've gotten this
         * far, we've got a LUN reservation.  Anything else got kicked out
         * above.  So, according to SPC, ignore the length.
         */

        mtx_lock(&lun->lun_lock);

        /*
         * According to SPC, it is not an error for an intiator to attempt
         * to release a reservation on a LUN that isn't reserved, or that
         * is reserved by another initiator.  The reservation can only be
         * released, though, by the initiator who made it or by one of
         * several reset type events.
         */
        if ((lun->flags & CTL_LUN_RESERVED) && (lun->res_idx == residx))
                        lun->flags &= ~CTL_LUN_RESERVED;

        mtx_unlock(&lun->lun_lock);

        ctl_set_success(ctsio);
        ctl_done((union ctl_io *)ctsio);
        return (CTL_RETVAL_COMPLETE);
}

int
ctl_scsi_reserve(struct ctl_scsiio *ctsio)
{
        struct ctl_lun *lun = CTL_LUN(ctsio);
        uint32_t residx;

        CTL_DEBUG_PRINT(("ctl_reserve\n"));

        residx = ctl_get_initindex(&ctsio->io_hdr.nexus);

        /*
         * XXX KDM right now, we only support LUN reservation.  We don't
         * support 3rd party reservations, or extent reservations, which
         * might actually need the parameter list.  If we've gotten this
         * far, we've got a LUN reservation.  Anything else got kicked out
         * above.  So, according to SPC, ignore the length.
         */

        mtx_lock(&lun->lun_lock);
        if ((lun->flags & CTL_LUN_RESERVED) && (lun->res_idx != residx)) {
                ctl_set_reservation_conflict(ctsio);
                goto bailout;
        }

        /* SPC-3 exceptions to SPC-2 RESERVE and RELEASE behavior. */
        if (lun->flags & CTL_LUN_PR_RESERVED) {
                ctl_set_success(ctsio);
                goto bailout;
        }

        lun->flags |= CTL_LUN_RESERVED;
        lun->res_idx = residx;
        ctl_set_success(ctsio);

bailout:
        mtx_unlock(&lun->lun_lock);
        ctl_done((union ctl_io *)ctsio);
        return (CTL_RETVAL_COMPLETE);
}

int
ctl_start_stop(struct ctl_scsiio *ctsio)
{
        struct ctl_lun *lun = CTL_LUN(ctsio);
        struct scsi_start_stop_unit *cdb;
        int retval;

        CTL_DEBUG_PRINT(("ctl_start_stop\n"));

        cdb = (struct scsi_start_stop_unit *)ctsio->cdb;

        if ((cdb->how & SSS_PC_MASK) == 0) {
                if ((lun->flags & CTL_LUN_PR_RESERVED) &&
                    (cdb->how & SSS_START) == 0) {
                        uint32_t residx;

                        residx = ctl_get_initindex(&ctsio->io_hdr.nexus);
                        if (ctl_get_prkey(lun, residx) == 0 ||
                            (lun->pr_res_idx != residx && lun->pr_res_type < 4)) {

                                ctl_set_reservation_conflict(ctsio);
                                ctl_done((union ctl_io *)ctsio);
                                return (CTL_RETVAL_COMPLETE);
                        }
                }

                if ((cdb->how & SSS_LOEJ) &&
                    (lun->flags & CTL_LUN_REMOVABLE) == 0) {
                        ctl_set_invalid_field(ctsio,
                                              /*sks_valid*/ 1,
                                              /*command*/ 1,
                                              /*field*/ 4,
                                              /*bit_valid*/ 1,
                                              /*bit*/ 1);
                        ctl_done((union ctl_io *)ctsio);
                        return (CTL_RETVAL_COMPLETE);
                }

                if ((cdb->how & SSS_START) == 0 && (cdb->how & SSS_LOEJ) &&
                    lun->prevent_count > 0) {
                        /* "Medium removal prevented" */
                        ctl_set_sense(ctsio, /*current_error*/ 1,
                            /*sense_key*/(lun->flags & CTL_LUN_NO_MEDIA) ?
                             SSD_KEY_NOT_READY : SSD_KEY_ILLEGAL_REQUEST,
                            /*asc*/ 0x53, /*ascq*/ 0x02, SSD_ELEM_NONE);
                        ctl_done((union ctl_io *)ctsio);
                        return (CTL_RETVAL_COMPLETE);
                }
        }

        retval = lun->backend->config_write((union ctl_io *)ctsio);
        return (retval);
}

int
ctl_prevent_allow(struct ctl_scsiio *ctsio)
{
        struct ctl_lun *lun = CTL_LUN(ctsio);
        struct scsi_prevent *cdb;
        int retval;
        uint32_t initidx;

        CTL_DEBUG_PRINT(("ctl_prevent_allow\n"));

        cdb = (struct scsi_prevent *)ctsio->cdb;

        if ((lun->flags & CTL_LUN_REMOVABLE) == 0 || lun->prevent == NULL) {
                ctl_set_invalid_opcode(ctsio);
                ctl_done((union ctl_io *)ctsio);
                return (CTL_RETVAL_COMPLETE);
        }

        initidx = ctl_get_initindex(&ctsio->io_hdr.nexus);
        mtx_lock(&lun->lun_lock);
        if ((cdb->how & PR_PREVENT) &&
            ctl_is_set(lun->prevent, initidx) == 0) {
                ctl_set_mask(lun->prevent, initidx);
                lun->prevent_count++;
        } else if ((cdb->how & PR_PREVENT) == 0 &&
            ctl_is_set(lun->prevent, initidx)) {
                ctl_clear_mask(lun->prevent, initidx);
                lun->prevent_count--;
        }
        mtx_unlock(&lun->lun_lock);
        retval = lun->backend->config_write((union ctl_io *)ctsio);
        return (retval);
}

/*
 * We support the SYNCHRONIZE CACHE command (10 and 16 byte versions), but
 * we don't really do anything with the LBA and length fields if the user
 * passes them in.  Instead we'll just flush out the cache for the entire
 * LUN.
 */
int
ctl_sync_cache(struct ctl_scsiio *ctsio)
{
        struct ctl_lun *lun = CTL_LUN(ctsio);
        struct ctl_lba_len_flags *lbalen;
        uint64_t starting_lba;
        uint32_t block_count;
        int retval;
        uint8_t byte2;

        CTL_DEBUG_PRINT(("ctl_sync_cache\n"));

        retval = 0;

        switch (ctsio->cdb[0]) {
        case SYNCHRONIZE_CACHE: {
                struct scsi_sync_cache *cdb;
                cdb = (struct scsi_sync_cache *)ctsio->cdb;

                starting_lba = scsi_4btoul(cdb->begin_lba);
                block_count = scsi_2btoul(cdb->lb_count);
                byte2 = cdb->byte2;
                break;
        }
        case SYNCHRONIZE_CACHE_16: {
                struct scsi_sync_cache_16 *cdb;
                cdb = (struct scsi_sync_cache_16 *)ctsio->cdb;

                starting_lba = scsi_8btou64(cdb->begin_lba);
                block_count = scsi_4btoul(cdb->lb_count);
                byte2 = cdb->byte2;
                break;
        }
        default:
                ctl_set_invalid_opcode(ctsio);
                ctl_done((union ctl_io *)ctsio);
                goto bailout;
                break; /* NOTREACHED */
        }

        /*
         * We check the LBA and length, but don't do anything with them.
         * A SYNCHRONIZE CACHE will cause the entire cache for this lun to
         * get flushed.  This check will just help satisfy anyone who wants
         * to see an error for an out of range LBA.
         */
        if ((starting_lba + block_count) > (lun->be_lun->maxlba + 1)) {
                ctl_set_lba_out_of_range(ctsio,
                    MAX(starting_lba, lun->be_lun->maxlba + 1));
                ctl_done((union ctl_io *)ctsio);
                goto bailout;
        }

        lbalen = (struct ctl_lba_len_flags *)&ctsio->io_hdr.ctl_private[CTL_PRIV_LBA_LEN];
        lbalen->lba = starting_lba;
        lbalen->len = block_count;
        lbalen->flags = byte2;
        retval = lun->backend->config_write((union ctl_io *)ctsio);

bailout:
        return (retval);
}

int
ctl_format(struct ctl_scsiio *ctsio)
{
        struct scsi_format *cdb;
        int length, defect_list_len;

        CTL_DEBUG_PRINT(("ctl_format\n"));

        cdb = (struct scsi_format *)ctsio->cdb;

        length = 0;
        if (cdb->byte2 & SF_FMTDATA) {
                if (cdb->byte2 & SF_LONGLIST)
                        length = sizeof(struct scsi_format_header_long);
                else
                        length = sizeof(struct scsi_format_header_short);
        }

        if (((ctsio->io_hdr.flags & CTL_FLAG_ALLOCATED) == 0)
         && (length > 0)) {
                ctsio->kern_data_ptr = malloc(length, M_CTL, M_WAITOK);
                ctsio->kern_data_len = length;
                ctsio->kern_total_len = length;
                ctsio->kern_rel_offset = 0;
                ctsio->kern_sg_entries = 0;
                ctsio->io_hdr.flags |= CTL_FLAG_ALLOCATED;
                ctsio->be_move_done = ctl_config_move_done;
                ctl_datamove((union ctl_io *)ctsio);

                return (CTL_RETVAL_COMPLETE);
        }

        defect_list_len = 0;

        if (cdb->byte2 & SF_FMTDATA) {
                if (cdb->byte2 & SF_LONGLIST) {
                        struct scsi_format_header_long *header;

                        header = (struct scsi_format_header_long *)
                                ctsio->kern_data_ptr;

                        defect_list_len = scsi_4btoul(header->defect_list_len);
                        if (defect_list_len != 0) {
                                ctl_set_invalid_field(ctsio,
                                                      /*sks_valid*/ 1,
                                                      /*command*/ 0,
                                                      /*field*/ 2,
                                                      /*bit_valid*/ 0,
                                                      /*bit*/ 0);
                                goto bailout;
                        }
                } else {
                        struct scsi_format_header_short *header;

                        header = (struct scsi_format_header_short *)
                                ctsio->kern_data_ptr;

                        defect_list_len = scsi_2btoul(header->defect_list_len);
                        if (defect_list_len != 0) {
                                ctl_set_invalid_field(ctsio,
                                                      /*sks_valid*/ 1,
                                                      /*command*/ 0,
                                                      /*field*/ 2,
                                                      /*bit_valid*/ 0,
                                                      /*bit*/ 0);
                                goto bailout;
                        }
                }
        }

        ctl_set_success(ctsio);
bailout:

        if (ctsio->io_hdr.flags & CTL_FLAG_ALLOCATED) {
                free(ctsio->kern_data_ptr, M_CTL);
                ctsio->io_hdr.flags &= ~CTL_FLAG_ALLOCATED;
        }

        ctl_done((union ctl_io *)ctsio);
        return (CTL_RETVAL_COMPLETE);
}

int
ctl_read_buffer(struct ctl_scsiio *ctsio)
{
        struct ctl_lun *lun = CTL_LUN(ctsio);
        uint64_t buffer_offset;
        uint32_t len;
        uint8_t byte2;
        static uint8_t descr[4];
        static uint8_t echo_descr[4] = { 0 };

        CTL_DEBUG_PRINT(("ctl_read_buffer\n"));

        switch (ctsio->cdb[0]) {
        case READ_BUFFER: {
                struct scsi_read_buffer *cdb;

                cdb = (struct scsi_read_buffer *)ctsio->cdb;
                buffer_offset = scsi_3btoul(cdb->offset);
                len = scsi_3btoul(cdb->length);
                byte2 = cdb->byte2;
                break;
        }
        case READ_BUFFER_16: {
                struct scsi_read_buffer_16 *cdb;

                cdb = (struct scsi_read_buffer_16 *)ctsio->cdb;
                buffer_offset = scsi_8btou64(cdb->offset);
                len = scsi_4btoul(cdb->length);
                byte2 = cdb->byte2;
                break;
        }
        default: /* This shouldn't happen. */
                ctl_set_invalid_opcode(ctsio);
                ctl_done((union ctl_io *)ctsio);
                return (CTL_RETVAL_COMPLETE);
        }

        if (buffer_offset > CTL_WRITE_BUFFER_SIZE ||
            buffer_offset + len > CTL_WRITE_BUFFER_SIZE) {
                ctl_set_invalid_field(ctsio,
                                      /*sks_valid*/ 1,
                                      /*command*/ 1,
                                      /*field*/ 6,
                                      /*bit_valid*/ 0,
                                      /*bit*/ 0);
                ctl_done((union ctl_io *)ctsio);
                return (CTL_RETVAL_COMPLETE);
        }

        if ((byte2 & RWB_MODE) == RWB_MODE_DESCR) {
                descr[0] = 0;
                scsi_ulto3b(CTL_WRITE_BUFFER_SIZE, &descr[1]);
                ctsio->kern_data_ptr = descr;
                len = min(len, sizeof(descr));
        } else if ((byte2 & RWB_MODE) == RWB_MODE_ECHO_DESCR) {
                ctsio->kern_data_ptr = echo_descr;
                len = min(len, sizeof(echo_descr));
        } else {
                if (lun->write_buffer == NULL) {
                        lun->write_buffer = malloc(CTL_WRITE_BUFFER_SIZE,
                            M_CTL, M_WAITOK);
                }
                ctsio->kern_data_ptr = lun->write_buffer + buffer_offset;
        }
        ctsio->kern_data_len = len;
        ctsio->kern_total_len = len;
        ctsio->kern_rel_offset = 0;
        ctsio->kern_sg_entries = 0;
        ctl_set_success(ctsio);
        ctsio->be_move_done = ctl_config_move_done;
        ctl_datamove((union ctl_io *)ctsio);
        return (CTL_RETVAL_COMPLETE);
}

int
ctl_write_buffer(struct ctl_scsiio *ctsio)
{
        struct ctl_lun *lun = CTL_LUN(ctsio);
        struct scsi_write_buffer *cdb;
        int buffer_offset, len;

        CTL_DEBUG_PRINT(("ctl_write_buffer\n"));

        cdb = (struct scsi_write_buffer *)ctsio->cdb;

        len = scsi_3btoul(cdb->length);
        buffer_offset = scsi_3btoul(cdb->offset);

        if (buffer_offset + len > CTL_WRITE_BUFFER_SIZE) {
                ctl_set_invalid_field(ctsio,
                                      /*sks_valid*/ 1,
                                      /*command*/ 1,
                                      /*field*/ 6,
                                      /*bit_valid*/ 0,
                                      /*bit*/ 0);
                ctl_done((union ctl_io *)ctsio);
                return (CTL_RETVAL_COMPLETE);
        }

        /*
         * If we've got a kernel request that hasn't been malloced yet,
         * malloc it and tell the caller the data buffer is here.
         */
        if ((ctsio->io_hdr.flags & CTL_FLAG_ALLOCATED) == 0) {
                if (lun->write_buffer == NULL) {
                        lun->write_buffer = malloc(CTL_WRITE_BUFFER_SIZE,
                            M_CTL, M_WAITOK);
                }
                ctsio->kern_data_ptr = lun->write_buffer + buffer_offset;
                ctsio->kern_data_len = len;
                ctsio->kern_total_len = len;
                ctsio->kern_rel_offset = 0;
                ctsio->kern_sg_entries = 0;
                ctsio->io_hdr.flags |= CTL_FLAG_ALLOCATED;
                ctsio->be_move_done = ctl_config_move_done;
                ctl_datamove((union ctl_io *)ctsio);

                return (CTL_RETVAL_COMPLETE);
        }

        ctl_set_success(ctsio);
        ctl_done((union ctl_io *)ctsio);
        return (CTL_RETVAL_COMPLETE);
}

static int
ctl_write_same_cont(union ctl_io *io)
{
        struct ctl_lun *lun = CTL_LUN(io);
        struct ctl_scsiio *ctsio;
        struct ctl_lba_len_flags *lbalen;
        int retval;

        ctsio = &io->scsiio;
        ctsio->io_hdr.status = CTL_STATUS_NONE;
        lbalen = (struct ctl_lba_len_flags *)
            &ctsio->io_hdr.ctl_private[CTL_PRIV_LBA_LEN];
        lbalen->lba += lbalen->len;
        if ((lun->be_lun->maxlba + 1) - lbalen->lba <= UINT32_MAX) {
                ctsio->io_hdr.flags &= ~CTL_FLAG_IO_CONT;
                lbalen->len = (lun->be_lun->maxlba + 1) - lbalen->lba;
        }

        CTL_DEBUG_PRINT(("ctl_write_same_cont: calling config_write()\n"));
        retval = lun->backend->config_write((union ctl_io *)ctsio);
        return (retval);
}

int
ctl_write_same(struct ctl_scsiio *ctsio)
{
        struct ctl_lun *lun = CTL_LUN(ctsio);
        struct ctl_lba_len_flags *lbalen;
        const char *val;
        uint64_t lba, ival;
        uint32_t num_blocks;
        int len, retval;
        uint8_t byte2;

        CTL_DEBUG_PRINT(("ctl_write_same\n"));

        switch (ctsio->cdb[0]) {
        case WRITE_SAME_10: {
                struct scsi_write_same_10 *cdb;

                cdb = (struct scsi_write_same_10 *)ctsio->cdb;

                lba = scsi_4btoul(cdb->addr);
                num_blocks = scsi_2btoul(cdb->length);
                byte2 = cdb->byte2;
                break;
        }
        case WRITE_SAME_16: {
                struct scsi_write_same_16 *cdb;

                cdb = (struct scsi_write_same_16 *)ctsio->cdb;

                lba = scsi_8btou64(cdb->addr);
                num_blocks = scsi_4btoul(cdb->length);
                byte2 = cdb->byte2;
                break;
        }
        default:
                /*
                 * We got a command we don't support.  This shouldn't
                 * happen, commands should be filtered out above us.
                 */
                ctl_set_invalid_opcode(ctsio);
                ctl_done((union ctl_io *)ctsio);

                return (CTL_RETVAL_COMPLETE);
                break; /* NOTREACHED */
        }

        /* ANCHOR flag can be used only together with UNMAP */
        if ((byte2 & SWS_UNMAP) == 0 && (byte2 & SWS_ANCHOR) != 0) {
                ctl_set_invalid_field(ctsio, /*sks_valid*/ 1,
                    /*command*/ 1, /*field*/ 1, /*bit_valid*/ 1, /*bit*/ 0);
                ctl_done((union ctl_io *)ctsio);
                return (CTL_RETVAL_COMPLETE);
        }

        /*
         * The first check is to make sure we're in bounds, the second
         * check is to catch wrap-around problems.  If the lba + num blocks
         * is less than the lba, then we've wrapped around and the block
         * range is invalid anyway.
         */
        if (((lba + num_blocks) > (lun->be_lun->maxlba + 1))
         || ((lba + num_blocks) < lba)) {
                ctl_set_lba_out_of_range(ctsio,
                    MAX(lba, lun->be_lun->maxlba + 1));
                ctl_done((union ctl_io *)ctsio);
                return (CTL_RETVAL_COMPLETE);
        }

        /* Zero number of blocks means "to the last logical block" */
        if (num_blocks == 0) {
                ival = UINT64_MAX;
                val = dnvlist_get_string(lun->be_lun->options,
                    "write_same_max_lba", NULL);
                if (val != NULL)
                        ctl_expand_number(val, &ival);
                if ((lun->be_lun->maxlba + 1) - lba > ival) {
                        ctl_set_invalid_field(ctsio,
                            /*sks_valid*/ 1, /*command*/ 1,
                            /*field*/ ctsio->cdb[0] == WRITE_SAME_10 ? 7 : 10,
                            /*bit_valid*/ 0, /*bit*/ 0);
                        ctl_done((union ctl_io *)ctsio);
                        return (CTL_RETVAL_COMPLETE);
                }
                if ((lun->be_lun->maxlba + 1) - lba > UINT32_MAX) {
                        ctsio->io_hdr.flags |= CTL_FLAG_IO_CONT;
                        ctsio->io_cont = ctl_write_same_cont;
                        num_blocks = 1 << 31;
                } else
                        num_blocks = (lun->be_lun->maxlba + 1) - lba;
        }

        len = lun->be_lun->blocksize;

        /*
         * If we've got a kernel request that hasn't been malloced yet,
         * malloc it and tell the caller the data buffer is here.
         */
        if ((byte2 & SWS_NDOB) == 0 &&
            (ctsio->io_hdr.flags & CTL_FLAG_ALLOCATED) == 0) {
                ctsio->kern_data_ptr = malloc(len, M_CTL, M_WAITOK);
                ctsio->kern_data_len = len;
                ctsio->kern_total_len = len;
                ctsio->kern_rel_offset = 0;
                ctsio->kern_sg_entries = 0;
                ctsio->io_hdr.flags |= CTL_FLAG_ALLOCATED;
                ctsio->be_move_done = ctl_config_move_done;
                ctl_datamove((union ctl_io *)ctsio);

                return (CTL_RETVAL_COMPLETE);
        }

        lbalen = (struct ctl_lba_len_flags *)&ctsio->io_hdr.ctl_private[CTL_PRIV_LBA_LEN];
        lbalen->lba = lba;
        lbalen->len = num_blocks;
        lbalen->flags = byte2;
        retval = lun->backend->config_write((union ctl_io *)ctsio);

        return (retval);
}

int
ctl_unmap(struct ctl_scsiio *ctsio)
{
        struct ctl_lun *lun = CTL_LUN(ctsio);
        struct scsi_unmap *cdb;
        struct ctl_ptr_len_flags *ptrlen;
        struct scsi_unmap_header *hdr;
        struct scsi_unmap_desc *buf, *end, *endnz, *range;
        uint64_t lba;
        uint32_t num_blocks;
        int len, retval;
        uint8_t byte2;

        CTL_DEBUG_PRINT(("ctl_unmap\n"));

        cdb = (struct scsi_unmap *)ctsio->cdb;
        len = scsi_2btoul(cdb->length);
        byte2 = cdb->byte2;

        /*
         * If we've got a kernel request that hasn't been malloced yet,
         * malloc it and tell the caller the data buffer is here.
         */
        if ((ctsio->io_hdr.flags & CTL_FLAG_ALLOCATED) == 0) {
                ctsio->kern_data_ptr = malloc(len, M_CTL, M_WAITOK);
                ctsio->kern_data_len = len;
                ctsio->kern_total_len = len;
                ctsio->kern_rel_offset = 0;
                ctsio->kern_sg_entries = 0;
                ctsio->io_hdr.flags |= CTL_FLAG_ALLOCATED;
                ctsio->be_move_done = ctl_config_move_done;
                ctl_datamove((union ctl_io *)ctsio);

                return (CTL_RETVAL_COMPLETE);
        }

        len = ctsio->kern_total_len - ctsio->kern_data_resid;
        hdr = (struct scsi_unmap_header *)ctsio->kern_data_ptr;
        if (len < sizeof (*hdr) ||
            len < (scsi_2btoul(hdr->length) + sizeof(hdr->length)) ||
            len < (scsi_2btoul(hdr->desc_length) + sizeof (*hdr)) ||
            scsi_2btoul(hdr->desc_length) % sizeof(*buf) != 0) {
                ctl_set_invalid_field(ctsio,
                                      /*sks_valid*/ 0,
                                      /*command*/ 0,
                                      /*field*/ 0,
                                      /*bit_valid*/ 0,
                                      /*bit*/ 0);
                goto done;
        }
        len = scsi_2btoul(hdr->desc_length);
        buf = (struct scsi_unmap_desc *)(hdr + 1);
        end = buf + len / sizeof(*buf);

        endnz = buf;
        for (range = buf; range < end; range++) {
                lba = scsi_8btou64(range->lba);
                num_blocks = scsi_4btoul(range->length);
                if (((lba + num_blocks) > (lun->be_lun->maxlba + 1))
                 || ((lba + num_blocks) < lba)) {
                        ctl_set_lba_out_of_range(ctsio,
                            MAX(lba, lun->be_lun->maxlba + 1));
                        ctl_done((union ctl_io *)ctsio);
                        return (CTL_RETVAL_COMPLETE);
                }
                if (num_blocks != 0)
                        endnz = range + 1;
        }

        /*
         * Block backend can not handle zero last range.
         * Filter it out and return if there is nothing left.
         */
        len = (uint8_t *)endnz - (uint8_t *)buf;
        if (len == 0) {
                ctl_set_success(ctsio);
                goto done;
        }

        mtx_lock(&lun->lun_lock);
        ptrlen = (struct ctl_ptr_len_flags *)
            &ctsio->io_hdr.ctl_private[CTL_PRIV_LBA_LEN];
        ptrlen->ptr = (void *)buf;
        ptrlen->len = len;
        ptrlen->flags = byte2;
        ctl_try_unblock_others(lun, (union ctl_io *)ctsio, FALSE);
        mtx_unlock(&lun->lun_lock);

        retval = lun->backend->config_write((union ctl_io *)ctsio);
        return (retval);

done:
        if (ctsio->io_hdr.flags & CTL_FLAG_ALLOCATED) {
                free(ctsio->kern_data_ptr, M_CTL);
                ctsio->io_hdr.flags &= ~CTL_FLAG_ALLOCATED;
        }
        ctl_done((union ctl_io *)ctsio);
        return (CTL_RETVAL_COMPLETE);
}

int
ctl_default_page_handler(struct ctl_scsiio *ctsio,
                         struct ctl_page_index *page_index, uint8_t *page_ptr)
{
        struct ctl_lun *lun = CTL_LUN(ctsio);
        uint8_t *current_cp;
        int set_ua;
        uint32_t initidx;

        initidx = ctl_get_initindex(&ctsio->io_hdr.nexus);
        set_ua = 0;

        current_cp = (page_index->page_data + (page_index->page_len *
            CTL_PAGE_CURRENT));

        mtx_lock(&lun->lun_lock);
        if (memcmp(current_cp, page_ptr, page_index->page_len)) {
                memcpy(current_cp, page_ptr, page_index->page_len);
                set_ua = 1;
        }
        if (set_ua != 0)
                ctl_est_ua_all(lun, initidx, CTL_UA_MODE_CHANGE);
        mtx_unlock(&lun->lun_lock);
        if (set_ua) {
                ctl_isc_announce_mode(lun,
                    ctl_get_initindex(&ctsio->io_hdr.nexus),
                    page_index->page_code, page_index->subpage);
        }
        return (CTL_RETVAL_COMPLETE);
}

static void
ctl_ie_timer(void *arg)
{
        struct ctl_lun *lun = arg;
        uint64_t t;

        if (lun->ie_asc == 0)
                return;

        if (lun->MODE_IE.mrie == SIEP_MRIE_UA)
                ctl_est_ua_all(lun, -1, CTL_UA_IE);
        else
                lun->ie_reported = 0;

        if (lun->ie_reportcnt < scsi_4btoul(lun->MODE_IE.report_count)) {
                lun->ie_reportcnt++;
                t = scsi_4btoul(lun->MODE_IE.interval_timer);
                if (t == 0 || t == UINT32_MAX)
                        t = 3000;  /* 5 min */
                callout_schedule(&lun->ie_callout, t * hz / 10);
        }
}

int
ctl_ie_page_handler(struct ctl_scsiio *ctsio,
                         struct ctl_page_index *page_index, uint8_t *page_ptr)
{
        struct ctl_lun *lun = CTL_LUN(ctsio);
        struct scsi_info_exceptions_page *pg;
        uint64_t t;

        (void)ctl_default_page_handler(ctsio, page_index, page_ptr);

        pg = (struct scsi_info_exceptions_page *)page_ptr;
        mtx_lock(&lun->lun_lock);
        if (pg->info_flags & SIEP_FLAGS_TEST) {
                lun->ie_asc = 0x5d;
                lun->ie_ascq = 0xff;
                if (pg->mrie == SIEP_MRIE_UA) {
                        ctl_est_ua_all(lun, -1, CTL_UA_IE);
                        lun->ie_reported = 1;
                } else {
                        ctl_clr_ua_all(lun, -1, CTL_UA_IE);
                        lun->ie_reported = -1;
                }
                lun->ie_reportcnt = 1;
                if (lun->ie_reportcnt < scsi_4btoul(pg->report_count)) {
                        lun->ie_reportcnt++;
                        t = scsi_4btoul(pg->interval_timer);
                        if (t == 0 || t == UINT32_MAX)
                                t = 3000;  /* 5 min */
                        callout_reset(&lun->ie_callout, t * hz / 10,
                            ctl_ie_timer, lun);
                }
        } else {
                lun->ie_asc = 0;
                lun->ie_ascq = 0;
                lun->ie_reported = 1;
                ctl_clr_ua_all(lun, -1, CTL_UA_IE);
                lun->ie_reportcnt = UINT32_MAX;
                callout_stop(&lun->ie_callout);
        }
        mtx_unlock(&lun->lun_lock);
        return (CTL_RETVAL_COMPLETE);
}

static int
ctl_do_mode_select(union ctl_io *io)
{
        struct ctl_lun *lun = CTL_LUN(io);
        struct scsi_mode_page_header *page_header;
        struct ctl_page_index *page_index;
        struct ctl_scsiio *ctsio;
        int page_len, page_len_offset, page_len_size;
        union ctl_modepage_info *modepage_info;
        uint16_t *len_left, *len_used;
        int retval, i;

        ctsio = &io->scsiio;
        page_index = NULL;
        page_len = 0;

        modepage_info = (union ctl_modepage_info *)
                ctsio->io_hdr.ctl_private[CTL_PRIV_MODEPAGE].bytes;
        len_left = &modepage_info->header.len_left;
        len_used = &modepage_info->header.len_used;

do_next_page:

        page_header = (struct scsi_mode_page_header *)
                (ctsio->kern_data_ptr + *len_used);

        if (*len_left == 0) {
                free(ctsio->kern_data_ptr, M_CTL);
                ctl_set_success(ctsio);
                ctl_done((union ctl_io *)ctsio);
                return (CTL_RETVAL_COMPLETE);
        } else if (*len_left < sizeof(struct scsi_mode_page_header)) {

                free(ctsio->kern_data_ptr, M_CTL);
                ctl_set_param_len_error(ctsio);
                ctl_done((union ctl_io *)ctsio);
                return (CTL_RETVAL_COMPLETE);

        } else if ((page_header->page_code & SMPH_SPF)
                && (*len_left < sizeof(struct scsi_mode_page_header_sp))) {

                free(ctsio->kern_data_ptr, M_CTL);
                ctl_set_param_len_error(ctsio);
                ctl_done((union ctl_io *)ctsio);
                return (CTL_RETVAL_COMPLETE);
        }


        /*
         * XXX KDM should we do something with the block descriptor?
         */
        for (i = 0; i < CTL_NUM_MODE_PAGES; i++) {
                page_index = &lun->mode_pages.index[i];
                if (lun->be_lun->lun_type == T_DIRECT &&
                    (page_index->page_flags & CTL_PAGE_FLAG_DIRECT) == 0)
                        continue;
                if (lun->be_lun->lun_type == T_PROCESSOR &&
                    (page_index->page_flags & CTL_PAGE_FLAG_PROC) == 0)
                        continue;
                if (lun->be_lun->lun_type == T_CDROM &&
                    (page_index->page_flags & CTL_PAGE_FLAG_CDROM) == 0)
                        continue;

                if ((page_index->page_code & SMPH_PC_MASK) !=
                    (page_header->page_code & SMPH_PC_MASK))
                        continue;

                /*
                 * If neither page has a subpage code, then we've got a
                 * match.
                 */
                if (((page_index->page_code & SMPH_SPF) == 0)
                 && ((page_header->page_code & SMPH_SPF) == 0)) {
                        page_len = page_header->page_length;
                        break;
                }

                /*
                 * If both pages have subpages, then the subpage numbers
                 * have to match.
                 */
                if ((page_index->page_code & SMPH_SPF)
                  && (page_header->page_code & SMPH_SPF)) {
                        struct scsi_mode_page_header_sp *sph;

                        sph = (struct scsi_mode_page_header_sp *)page_header;
                        if (page_index->subpage == sph->subpage) {
                                page_len = scsi_2btoul(sph->page_length);
                                break;
                        }
                }
        }

        /*
         * If we couldn't find the page, or if we don't have a mode select
         * handler for it, send back an error to the user.
         */
        if ((i >= CTL_NUM_MODE_PAGES)
         || (page_index->select_handler == NULL)) {
                ctl_set_invalid_field(ctsio,
                                      /*sks_valid*/ 1,
                                      /*command*/ 0,
                                      /*field*/ *len_used,
                                      /*bit_valid*/ 0,
                                      /*bit*/ 0);
                free(ctsio->kern_data_ptr, M_CTL);
                ctl_done((union ctl_io *)ctsio);
                return (CTL_RETVAL_COMPLETE);
        }

        if (page_index->page_code & SMPH_SPF) {
                page_len_offset = 2;
                page_len_size = 2;
        } else {
                page_len_size = 1;
                page_len_offset = 1;
        }

        /*
         * If the length the initiator gives us isn't the one we specify in
         * the mode page header, or if they didn't specify enough data in
         * the CDB to avoid truncating this page, kick out the request.
         */
        if (page_len != page_index->page_len - page_len_offset - page_len_size) {
                ctl_set_invalid_field(ctsio,
                                      /*sks_valid*/ 1,
                                      /*command*/ 0,
                                      /*field*/ *len_used + page_len_offset,
                                      /*bit_valid*/ 0,
                                      /*bit*/ 0);
                free(ctsio->kern_data_ptr, M_CTL);
                ctl_done((union ctl_io *)ctsio);
                return (CTL_RETVAL_COMPLETE);
        }
        if (*len_left < page_index->page_len) {
                free(ctsio->kern_data_ptr, M_CTL);
                ctl_set_param_len_error(ctsio);
                ctl_done((union ctl_io *)ctsio);
                return (CTL_RETVAL_COMPLETE);
        }

        /*
         * Run through the mode page, checking to make sure that the bits
         * the user changed are actually legal for him to change.
         */
        for (i = 0; i < page_index->page_len; i++) {
                uint8_t *user_byte, *change_mask, *current_byte;
                int bad_bit;
                int j;

                user_byte = (uint8_t *)page_header + i;
                change_mask = page_index->page_data +
                              (page_index->page_len * CTL_PAGE_CHANGEABLE) + i;
                current_byte = page_index->page_data +
                               (page_index->page_len * CTL_PAGE_CURRENT) + i;

                /*
                 * Check to see whether the user set any bits in this byte
                 * that he is not allowed to set.
                 */
                if ((*user_byte & ~(*change_mask)) ==
                    (*current_byte & ~(*change_mask)))
                        continue;

                /*
                 * Go through bit by bit to determine which one is illegal.
                 */
                bad_bit = 0;
                for (j = 7; j >= 0; j--) {
                        if ((((1 << i) & ~(*change_mask)) & *user_byte) !=
                            (((1 << i) & ~(*change_mask)) & *current_byte)) {
                                bad_bit = i;
                                break;
                        }
                }
                ctl_set_invalid_field(ctsio,
                                      /*sks_valid*/ 1,
                                      /*command*/ 0,
                                      /*field*/ *len_used + i,
                                      /*bit_valid*/ 1,
                                      /*bit*/ bad_bit);
                free(ctsio->kern_data_ptr, M_CTL);
                ctl_done((union ctl_io *)ctsio);
                return (CTL_RETVAL_COMPLETE);
        }

        /*
         * Decrement these before we call the page handler, since we may
         * end up getting called back one way or another before the handler
         * returns to this context.
         */
        *len_left -= page_index->page_len;
        *len_used += page_index->page_len;

        retval = page_index->select_handler(ctsio, page_index,
                                            (uint8_t *)page_header);

        /*
         * If the page handler returns CTL_RETVAL_QUEUED, then we need to
         * wait until this queued command completes to finish processing
         * the mode page.  If it returns anything other than
         * CTL_RETVAL_COMPLETE (e.g. CTL_RETVAL_ERROR), then it should have
         * already set the sense information, freed the data pointer, and
         * completed the io for us.
         */
        if (retval != CTL_RETVAL_COMPLETE)
                goto bailout_no_done;

        /*
         * If the initiator sent us more than one page, parse the next one.
         */
        if (*len_left > 0)
                goto do_next_page;

        ctl_set_success(ctsio);
        free(ctsio->kern_data_ptr, M_CTL);
        ctl_done((union ctl_io *)ctsio);

bailout_no_done:

        return (CTL_RETVAL_COMPLETE);

}

int
ctl_mode_select(struct ctl_scsiio *ctsio)
{
        struct ctl_lun *lun = CTL_LUN(ctsio);
        union ctl_modepage_info *modepage_info;
        int bd_len, i, header_size, param_len, rtd;
        uint32_t initidx;

        initidx = ctl_get_initindex(&ctsio->io_hdr.nexus);
        switch (ctsio->cdb[0]) {
        case MODE_SELECT_6: {
                struct scsi_mode_select_6 *cdb;

                cdb = (struct scsi_mode_select_6 *)ctsio->cdb;

                rtd = (cdb->byte2 & SMS_RTD) ? 1 : 0;
                param_len = cdb->length;
                header_size = sizeof(struct scsi_mode_header_6);
                break;
        }
        case MODE_SELECT_10: {
                struct scsi_mode_select_10 *cdb;

                cdb = (struct scsi_mode_select_10 *)ctsio->cdb;

                rtd = (cdb->byte2 & SMS_RTD) ? 1 : 0;
                param_len = scsi_2btoul(cdb->length);
                header_size = sizeof(struct scsi_mode_header_10);
                break;
        }
        default:
                ctl_set_invalid_opcode(ctsio);
                ctl_done((union ctl_io *)ctsio);
                return (CTL_RETVAL_COMPLETE);
        }

        if (rtd) {
                if (param_len != 0) {
                        ctl_set_invalid_field(ctsio, /*sks_valid*/ 0,
                            /*command*/ 1, /*field*/ 0,
                            /*bit_valid*/ 0, /*bit*/ 0);
                        ctl_done((union ctl_io *)ctsio);
                        return (CTL_RETVAL_COMPLETE);
                }

                /* Revert to defaults. */
                ctl_init_page_index(lun);
                mtx_lock(&lun->lun_lock);
                ctl_est_ua_all(lun, initidx, CTL_UA_MODE_CHANGE);
                mtx_unlock(&lun->lun_lock);
                for (i = 0; i < CTL_NUM_MODE_PAGES; i++) {
                        ctl_isc_announce_mode(lun, -1,
                            lun->mode_pages.index[i].page_code & SMPH_PC_MASK,
                            lun->mode_pages.index[i].subpage);
                }
                ctl_set_success(ctsio);
                ctl_done((union ctl_io *)ctsio);
                return (CTL_RETVAL_COMPLETE);
        }

        /*
         * From SPC-3:
         * "A parameter list length of zero indicates that the Data-Out Buffer
         * shall be empty. This condition shall not be considered as an error."
         */
        if (param_len == 0) {
                ctl_set_success(ctsio);
                ctl_done((union ctl_io *)ctsio);
                return (CTL_RETVAL_COMPLETE);
        }

        /*
         * Since we'll hit this the first time through, prior to
         * allocation, we don't need to free a data buffer here.
         */
        if (param_len < header_size) {
                ctl_set_param_len_error(ctsio);
                ctl_done((union ctl_io *)ctsio);
                return (CTL_RETVAL_COMPLETE);
        }

        /*
         * Allocate the data buffer and grab the user's data.  In theory,
         * we shouldn't have to sanity check the parameter list length here
         * because the maximum size is 64K.  We should be able to malloc
         * that much without too many problems.
         */
        if ((ctsio->io_hdr.flags & CTL_FLAG_ALLOCATED) == 0) {
                ctsio->kern_data_ptr = malloc(param_len, M_CTL, M_WAITOK);
                ctsio->kern_data_len = param_len;
                ctsio->kern_total_len = param_len;
                ctsio->kern_rel_offset = 0;
                ctsio->kern_sg_entries = 0;
                ctsio->io_hdr.flags |= CTL_FLAG_ALLOCATED;
                ctsio->be_move_done = ctl_config_move_done;
                ctl_datamove((union ctl_io *)ctsio);

                return (CTL_RETVAL_COMPLETE);
        }

        switch (ctsio->cdb[0]) {
        case MODE_SELECT_6: {
                struct scsi_mode_header_6 *mh6;

                mh6 = (struct scsi_mode_header_6 *)ctsio->kern_data_ptr;
                bd_len = mh6->blk_desc_len;
                break;
        }
        case MODE_SELECT_10: {
                struct scsi_mode_header_10 *mh10;

                mh10 = (struct scsi_mode_header_10 *)ctsio->kern_data_ptr;
                bd_len = scsi_2btoul(mh10->blk_desc_len);
                break;
        }
        default:
                panic("%s: Invalid CDB type %#x", __func__, ctsio->cdb[0]);
        }

        if (param_len < (header_size + bd_len)) {
                free(ctsio->kern_data_ptr, M_CTL);
                ctl_set_param_len_error(ctsio);
                ctl_done((union ctl_io *)ctsio);
                return (CTL_RETVAL_COMPLETE);
        }

        /*
         * Set the IO_CONT flag, so that if this I/O gets passed to
         * ctl_config_write_done(), it'll get passed back to
         * ctl_do_mode_select() for further processing, or completion if
         * we're all done.
         */
        ctsio->io_hdr.flags |= CTL_FLAG_IO_CONT;
        ctsio->io_cont = ctl_do_mode_select;

        modepage_info = (union ctl_modepage_info *)
                ctsio->io_hdr.ctl_private[CTL_PRIV_MODEPAGE].bytes;
        memset(modepage_info, 0, sizeof(*modepage_info));
        modepage_info->header.len_left = param_len - header_size - bd_len;
        modepage_info->header.len_used = header_size + bd_len;

        return (ctl_do_mode_select((union ctl_io *)ctsio));
}

int
ctl_mode_sense(struct ctl_scsiio *ctsio)
{
        struct ctl_lun *lun = CTL_LUN(ctsio);
        int pc, page_code, llba, subpage;
        int alloc_len, page_len, header_len, bd_len, total_len;
        void *block_desc;
        struct ctl_page_index *page_index;

        llba = 0;

        CTL_DEBUG_PRINT(("ctl_mode_sense\n"));

        switch (ctsio->cdb[0]) {
        case MODE_SENSE_6: {
                struct scsi_mode_sense_6 *cdb;

                cdb = (struct scsi_mode_sense_6 *)ctsio->cdb;

                header_len = sizeof(struct scsi_mode_hdr_6);
                if (cdb->byte2 & SMS_DBD)
                        bd_len = 0;
                else
                        bd_len = sizeof(struct scsi_mode_block_descr);
                header_len += bd_len;

                pc = (cdb->page & SMS_PAGE_CTRL_MASK) >> 6;
                page_code = cdb->page & SMS_PAGE_CODE;
                subpage = cdb->subpage;
                alloc_len = cdb->length;
                break;
        }
        case MODE_SENSE_10: {
                struct scsi_mode_sense_10 *cdb;

                cdb = (struct scsi_mode_sense_10 *)ctsio->cdb;

                header_len = sizeof(struct scsi_mode_hdr_10);
                if (cdb->byte2 & SMS_DBD) {
                        bd_len = 0;
                } else if (lun->be_lun->lun_type == T_DIRECT) {
                        if (cdb->byte2 & SMS10_LLBAA) {
                                llba = 1;
                                bd_len = sizeof(struct scsi_mode_block_descr_dlong);
                        } else
                                bd_len = sizeof(struct scsi_mode_block_descr_dshort);
                } else
                        bd_len = sizeof(struct scsi_mode_block_descr);
                header_len += bd_len;

                pc = (cdb->page & SMS_PAGE_CTRL_MASK) >> 6;
                page_code = cdb->page & SMS_PAGE_CODE;
                subpage = cdb->subpage;
                alloc_len = scsi_2btoul(cdb->length);
                break;
        }
        default:
                ctl_set_invalid_opcode(ctsio);
                ctl_done((union ctl_io *)ctsio);
                return (CTL_RETVAL_COMPLETE);
                break; /* NOTREACHED */
        }

        /*
         * We have to make a first pass through to calculate the size of
         * the pages that match the user's query.  Then we allocate enough
         * memory to hold it, and actually copy the data into the buffer.
         */
        switch (page_code) {
        case SMS_ALL_PAGES_PAGE: {
                u_int i;

                page_len = 0;

                /*
                 * At the moment, values other than 0 and 0xff here are
                 * reserved according to SPC-3.
                 */
                if ((subpage != SMS_SUBPAGE_PAGE_0)
                 && (subpage != SMS_SUBPAGE_ALL)) {
                        ctl_set_invalid_field(ctsio,
                                              /*sks_valid*/ 1,
                                              /*command*/ 1,
                                              /*field*/ 3,
                                              /*bit_valid*/ 0,
                                              /*bit*/ 0);
                        ctl_done((union ctl_io *)ctsio);
                        return (CTL_RETVAL_COMPLETE);
                }

                for (i = 0; i < CTL_NUM_MODE_PAGES; i++) {
                        page_index = &lun->mode_pages.index[i];

                        /* Make sure the page is supported for this dev type */
                        if (lun->be_lun->lun_type == T_DIRECT &&
                            (page_index->page_flags & CTL_PAGE_FLAG_DIRECT) == 0)
                                continue;
                        if (lun->be_lun->lun_type == T_PROCESSOR &&
                            (page_index->page_flags & CTL_PAGE_FLAG_PROC) == 0)
                                continue;
                        if (lun->be_lun->lun_type == T_CDROM &&
                            (page_index->page_flags & CTL_PAGE_FLAG_CDROM) == 0)
                                continue;

                        /*
                         * We don't use this subpage if the user didn't
                         * request all subpages.
                         */
                        if ((page_index->subpage != 0)
                         && (subpage == SMS_SUBPAGE_PAGE_0))
                                continue;

                        page_len += page_index->page_len;
                }
                break;
        }
        default: {
                u_int i;

                page_len = 0;

                for (i = 0; i < CTL_NUM_MODE_PAGES; i++) {
                        page_index = &lun->mode_pages.index[i];

                        /* Make sure the page is supported for this dev type */
                        if (lun->be_lun->lun_type == T_DIRECT &&
                            (page_index->page_flags & CTL_PAGE_FLAG_DIRECT) == 0)
                                continue;
                        if (lun->be_lun->lun_type == T_PROCESSOR &&
                            (page_index->page_flags & CTL_PAGE_FLAG_PROC) == 0)
                                continue;
                        if (lun->be_lun->lun_type == T_CDROM &&
                            (page_index->page_flags & CTL_PAGE_FLAG_CDROM) == 0)
                                continue;

                        /* Look for the right page code */
                        if ((page_index->page_code & SMPH_PC_MASK) != page_code)
                                continue;

                        /* Look for the right subpage or the subpage wildcard*/
                        if ((page_index->subpage != subpage)
                         && (subpage != SMS_SUBPAGE_ALL))
                                continue;

                        page_len += page_index->page_len;
                }

                if (page_len == 0) {
                        ctl_set_invalid_field(ctsio,
                                              /*sks_valid*/ 1,
                                              /*command*/ 1,
                                              /*field*/ 2,
                                              /*bit_valid*/ 1,
                                              /*bit*/ 5);
                        ctl_done((union ctl_io *)ctsio);
                        return (CTL_RETVAL_COMPLETE);
                }
                break;
        }
        }

        total_len = header_len + page_len;

        ctsio->kern_data_ptr = malloc(total_len, M_CTL, M_WAITOK | M_ZERO);
        ctsio->kern_sg_entries = 0;
        ctsio->kern_rel_offset = 0;
        ctsio->kern_data_len = min(total_len, alloc_len);
        ctsio->kern_total_len = ctsio->kern_data_len;

        switch (ctsio->cdb[0]) {
        case MODE_SENSE_6: {
                struct scsi_mode_hdr_6 *header;

                header = (struct scsi_mode_hdr_6 *)ctsio->kern_data_ptr;

                header->datalen = MIN(total_len - 1, 254);
                if (lun->be_lun->lun_type == T_DIRECT) {
                        header->dev_specific = 0x10; /* DPOFUA */
                        if ((lun->be_lun->flags & CTL_LUN_FLAG_READONLY) ||
                            (lun->MODE_CTRL.eca_and_aen & SCP_SWP) != 0)
                                header->dev_specific |= 0x80; /* WP */
                }
                header->block_descr_len = bd_len;
                block_desc = &header[1];
                break;
        }
        case MODE_SENSE_10: {
                struct scsi_mode_hdr_10 *header;
                int datalen;

                header = (struct scsi_mode_hdr_10 *)ctsio->kern_data_ptr;

                datalen = MIN(total_len - 2, 65533);
                scsi_ulto2b(datalen, header->datalen);
                if (lun->be_lun->lun_type == T_DIRECT) {
                        header->dev_specific = 0x10; /* DPOFUA */
                        if ((lun->be_lun->flags & CTL_LUN_FLAG_READONLY) ||
                            (lun->MODE_CTRL.eca_and_aen & SCP_SWP) != 0)
                                header->dev_specific |= 0x80; /* WP */
                }
                if (llba)
                        header->flags |= SMH_LONGLBA;
                scsi_ulto2b(bd_len, header->block_descr_len);
                block_desc = &header[1];
                break;
        }
        default:
                panic("%s: Invalid CDB type %#x", __func__, ctsio->cdb[0]);
        }

        /*
         * If we've got a disk, use its blocksize in the block
         * descriptor.  Otherwise, just set it to 0.
         */
        if (bd_len > 0) {
                if (lun->be_lun->lun_type == T_DIRECT) {
                        if (llba) {
                                struct scsi_mode_block_descr_dlong *bd = block_desc;
                                if (lun->be_lun->maxlba != 0)
                                        scsi_u64to8b(lun->be_lun->maxlba + 1,
                                            bd->num_blocks);
                                scsi_ulto4b(lun->be_lun->blocksize,
                                    bd->block_len);
                        } else {
                                struct scsi_mode_block_descr_dshort *bd = block_desc;
                                if (lun->be_lun->maxlba != 0)
                                        scsi_ulto4b(MIN(lun->be_lun->maxlba+1,
                                            UINT32_MAX), bd->num_blocks);
                                scsi_ulto3b(lun->be_lun->blocksize,
                                    bd->block_len);
                        }
                } else {
                        struct scsi_mode_block_descr *bd = block_desc;
                        scsi_ulto3b(0, bd->block_len);
                }
        }

        switch (page_code) {
        case SMS_ALL_PAGES_PAGE: {
                int i, data_used;

                data_used = header_len;
                for (i = 0; i < CTL_NUM_MODE_PAGES; i++) {
                        struct ctl_page_index *page_index;

                        page_index = &lun->mode_pages.index[i];
                        if (lun->be_lun->lun_type == T_DIRECT &&
                            (page_index->page_flags & CTL_PAGE_FLAG_DIRECT) == 0)
                                continue;
                        if (lun->be_lun->lun_type == T_PROCESSOR &&
                            (page_index->page_flags & CTL_PAGE_FLAG_PROC) == 0)
                                continue;
                        if (lun->be_lun->lun_type == T_CDROM &&
                            (page_index->page_flags & CTL_PAGE_FLAG_CDROM) == 0)
                                continue;

                        /*
                         * We don't use this subpage if the user didn't
                         * request all subpages.  We already checked (above)
                         * to make sure the user only specified a subpage
                         * of 0 or 0xff in the SMS_ALL_PAGES_PAGE case.
                         */
                        if ((page_index->subpage != 0)
                         && (subpage == SMS_SUBPAGE_PAGE_0))
                                continue;

                        /*
                         * Call the handler, if it exists, to update the
                         * page to the latest values.
                         */
                        if (page_index->sense_handler != NULL)
                                page_index->sense_handler(ctsio, page_index,pc);

                        memcpy(ctsio->kern_data_ptr + data_used,
                               page_index->page_data +
                               (page_index->page_len * pc),
                               page_index->page_len);
                        data_used += page_index->page_len;
                }
                break;
        }
        default: {
                int i, data_used;

                data_used = header_len;

                for (i = 0; i < CTL_NUM_MODE_PAGES; i++) {
                        struct ctl_page_index *page_index;

                        page_index = &lun->mode_pages.index[i];

                        /* Look for the right page code */
                        if ((page_index->page_code & SMPH_PC_MASK) != page_code)
                                continue;

                        /* Look for the right subpage or the subpage wildcard*/
                        if ((page_index->subpage != subpage)
                         && (subpage != SMS_SUBPAGE_ALL))
                                continue;

                        /* Make sure the page is supported for this dev type */
                        if (lun->be_lun->lun_type == T_DIRECT &&
                            (page_index->page_flags & CTL_PAGE_FLAG_DIRECT) == 0)
                                continue;
                        if (lun->be_lun->lun_type == T_PROCESSOR &&
                            (page_index->page_flags & CTL_PAGE_FLAG_PROC) == 0)
                                continue;
                        if (lun->be_lun->lun_type == T_CDROM &&
                            (page_index->page_flags & CTL_PAGE_FLAG_CDROM) == 0)
                                continue;

                        /*
                         * Call the handler, if it exists, to update the
                         * page to the latest values.
                         */
                        if (page_index->sense_handler != NULL)
                                page_index->sense_handler(ctsio, page_index,pc);

                        memcpy(ctsio->kern_data_ptr + data_used,
                               page_index->page_data +
                               (page_index->page_len * pc),
                               page_index->page_len);
                        data_used += page_index->page_len;
                }
                break;
        }
        }

        ctl_set_success(ctsio);
        ctsio->io_hdr.flags |= CTL_FLAG_ALLOCATED;
        ctsio->be_move_done = ctl_config_move_done;
        ctl_datamove((union ctl_io *)ctsio);
        return (CTL_RETVAL_COMPLETE);
}

int
ctl_temp_log_sense_handler(struct ctl_scsiio *ctsio,
                               struct ctl_page_index *page_index,
                               int pc)
{
        struct ctl_lun *lun = CTL_LUN(ctsio);
        struct scsi_log_temperature *data;
        const char *value;

        data = (struct scsi_log_temperature *)page_index->page_data;

        scsi_ulto2b(SLP_TEMPERATURE, data->hdr.param_code);
        data->hdr.param_control = SLP_LBIN;
        data->hdr.param_len = sizeof(struct scsi_log_temperature) -
            sizeof(struct scsi_log_param_header);
        if ((value = dnvlist_get_string(lun->be_lun->options, "temperature",
            NULL)) != NULL)
                data->temperature = strtol(value, NULL, 0);
        else
                data->temperature = 0xff;
        data++;

        scsi_ulto2b(SLP_REFTEMPERATURE, data->hdr.param_code);
        data->hdr.param_control = SLP_LBIN;
        data->hdr.param_len = sizeof(struct scsi_log_temperature) -
            sizeof(struct scsi_log_param_header);
        if ((value = dnvlist_get_string(lun->be_lun->options, "reftemperature",
            NULL)) != NULL)
                data->temperature = strtol(value, NULL, 0);
        else
                data->temperature = 0xff;
        return (0);
}

int
ctl_lbp_log_sense_handler(struct ctl_scsiio *ctsio,
                               struct ctl_page_index *page_index,
                               int pc)
{
        struct ctl_lun *lun = CTL_LUN(ctsio);
        struct scsi_log_param_header *phdr;
        uint8_t *data;
        uint64_t val;

        data = page_index->page_data;

        if (lun->backend->lun_attr != NULL &&
            (val = lun->backend->lun_attr(lun->be_lun, "blocksavail"))
             != UINT64_MAX) {
                phdr = (struct scsi_log_param_header *)data;
                scsi_ulto2b(0x0001, phdr->param_code);
                phdr->param_control = SLP_LBIN | SLP_LP;
                phdr->param_len = 8;
                data = (uint8_t *)(phdr + 1);
                scsi_ulto4b(val >> CTL_LBP_EXPONENT, data);
                data[4] = 0x02; /* per-pool */
                data += phdr->param_len;
        }

        if (lun->backend->lun_attr != NULL &&
            (val = lun->backend->lun_attr(lun->be_lun, "blocksused"))
             != UINT64_MAX) {
                phdr = (struct scsi_log_param_header *)data;
                scsi_ulto2b(0x0002, phdr->param_code);
                phdr->param_control = SLP_LBIN | SLP_LP;
                phdr->param_len = 8;
                data = (uint8_t *)(phdr + 1);
                scsi_ulto4b(val >> CTL_LBP_EXPONENT, data);
                data[4] = 0x01; /* per-LUN */
                data += phdr->param_len;
        }

        if (lun->backend->lun_attr != NULL &&
            (val = lun->backend->lun_attr(lun->be_lun, "poolblocksavail"))
             != UINT64_MAX) {
                phdr = (struct scsi_log_param_header *)data;
                scsi_ulto2b(0x00f1, phdr->param_code);
                phdr->param_control = SLP_LBIN | SLP_LP;
                phdr->param_len = 8;
                data = (uint8_t *)(phdr + 1);
                scsi_ulto4b(val >> CTL_LBP_EXPONENT, data);
                data[4] = 0x02; /* per-pool */
                data += phdr->param_len;
        }

        if (lun->backend->lun_attr != NULL &&
            (val = lun->backend->lun_attr(lun->be_lun, "poolblocksused"))
             != UINT64_MAX) {
                phdr = (struct scsi_log_param_header *)data;
                scsi_ulto2b(0x00f2, phdr->param_code);
                phdr->param_control = SLP_LBIN | SLP_LP;
                phdr->param_len = 8;
                data = (uint8_t *)(phdr + 1);
                scsi_ulto4b(val >> CTL_LBP_EXPONENT, data);
                data[4] = 0x02; /* per-pool */
                data += phdr->param_len;
        }

        page_index->page_len = data - page_index->page_data;
        return (0);
}

int
ctl_sap_log_sense_handler(struct ctl_scsiio *ctsio,
                               struct ctl_page_index *page_index,
                               int pc)
{
        struct ctl_lun *lun = CTL_LUN(ctsio);
        struct stat_page *data;
        struct bintime *t;

        data = (struct stat_page *)page_index->page_data;

        scsi_ulto2b(SLP_SAP, data->sap.hdr.param_code);
        data->sap.hdr.param_control = SLP_LBIN;
        data->sap.hdr.param_len = sizeof(struct scsi_log_stat_and_perf) -
            sizeof(struct scsi_log_param_header);
        scsi_u64to8b(lun->stats.operations[CTL_STATS_READ],
            data->sap.read_num);
        scsi_u64to8b(lun->stats.operations[CTL_STATS_WRITE],
            data->sap.write_num);
        if (lun->be_lun->blocksize > 0) {
                scsi_u64to8b(lun->stats.bytes[CTL_STATS_WRITE] /
                    lun->be_lun->blocksize, data->sap.recvieved_lba);
                scsi_u64to8b(lun->stats.bytes[CTL_STATS_READ] /
                    lun->be_lun->blocksize, data->sap.transmitted_lba);
        }
        t = &lun->stats.time[CTL_STATS_READ];
        scsi_u64to8b((uint64_t)t->sec * 1000 + t->frac / (UINT64_MAX / 1000),
            data->sap.read_int);
        t = &lun->stats.time[CTL_STATS_WRITE];
        scsi_u64to8b((uint64_t)t->sec * 1000 + t->frac / (UINT64_MAX / 1000),
            data->sap.write_int);
        scsi_u64to8b(0, data->sap.weighted_num);
        scsi_u64to8b(0, data->sap.weighted_int);
        scsi_ulto2b(SLP_IT, data->it.hdr.param_code);
        data->it.hdr.param_control = SLP_LBIN;
        data->it.hdr.param_len = sizeof(struct scsi_log_idle_time) -
            sizeof(struct scsi_log_param_header);
#ifdef CTL_TIME_IO
        scsi_u64to8b(lun->idle_time / SBT_1MS, data->it.idle_int);
#endif
        scsi_ulto2b(SLP_TI, data->ti.hdr.param_code);
        data->it.hdr.param_control = SLP_LBIN;
        data->ti.hdr.param_len = sizeof(struct scsi_log_time_interval) -
            sizeof(struct scsi_log_param_header);
        scsi_ulto4b(3, data->ti.exponent);
        scsi_ulto4b(1, data->ti.integer);
        return (0);
}

int
ctl_ie_log_sense_handler(struct ctl_scsiio *ctsio,
                               struct ctl_page_index *page_index,
                               int pc)
{
        struct ctl_lun *lun = CTL_LUN(ctsio);
        struct scsi_log_informational_exceptions *data;
        const char *value;

        data = (struct scsi_log_informational_exceptions *)page_index->page_data;

        scsi_ulto2b(SLP_IE_GEN, data->hdr.param_code);
        data->hdr.param_control = SLP_LBIN;
        data->hdr.param_len = sizeof(struct scsi_log_informational_exceptions) -
            sizeof(struct scsi_log_param_header);
        data->ie_asc = lun->ie_asc;
        data->ie_ascq = lun->ie_ascq;
        if ((value = dnvlist_get_string(lun->be_lun->options, "temperature",
            NULL)) != NULL)
                data->temperature = strtol(value, NULL, 0);
        else
                data->temperature = 0xff;
        return (0);
}

int
ctl_log_sense(struct ctl_scsiio *ctsio)
{
        struct ctl_lun *lun = CTL_LUN(ctsio);
        int i, pc, page_code, subpage;
        int alloc_len, total_len;
        struct ctl_page_index *page_index;
        struct scsi_log_sense *cdb;
        struct scsi_log_header *header;

        CTL_DEBUG_PRINT(("ctl_log_sense\n"));

        cdb = (struct scsi_log_sense *)ctsio->cdb;
        pc = (cdb->page & SLS_PAGE_CTRL_MASK) >> 6;
        page_code = cdb->page & SLS_PAGE_CODE;
        subpage = cdb->subpage;
        alloc_len = scsi_2btoul(cdb->length);

        page_index = NULL;
        for (i = 0; i < CTL_NUM_LOG_PAGES; i++) {
                page_index = &lun->log_pages.index[i];

                /* Look for the right page code */
                if ((page_index->page_code & SL_PAGE_CODE) != page_code)
                        continue;

                /* Look for the right subpage or the subpage wildcard*/
                if (page_index->subpage != subpage)
                        continue;

                break;
        }
        if (i >= CTL_NUM_LOG_PAGES) {
                ctl_set_invalid_field(ctsio,
                                      /*sks_valid*/ 1,
                                      /*command*/ 1,
                                      /*field*/ 2,
                                      /*bit_valid*/ 0,
                                      /*bit*/ 0);
                ctl_done((union ctl_io *)ctsio);
                return (CTL_RETVAL_COMPLETE);
        }

        total_len = sizeof(struct scsi_log_header) + page_index->page_len;

        ctsio->kern_data_ptr = malloc(total_len, M_CTL, M_WAITOK | M_ZERO);
        ctsio->kern_sg_entries = 0;
        ctsio->kern_rel_offset = 0;
        ctsio->kern_data_len = min(total_len, alloc_len);
        ctsio->kern_total_len = ctsio->kern_data_len;

        header = (struct scsi_log_header *)ctsio->kern_data_ptr;
        header->page = page_index->page_code;
        if (page_index->page_code == SLS_LOGICAL_BLOCK_PROVISIONING)
                header->page |= SL_DS;
        if (page_index->subpage) {
                header->page |= SL_SPF;
                header->subpage = page_index->subpage;
        }
        scsi_ulto2b(page_index->page_len, header->datalen);

        /*
         * Call the handler, if it exists, to update the
         * page to the latest values.
         */
        if (page_index->sense_handler != NULL)
                page_index->sense_handler(ctsio, page_index, pc);

        memcpy(header + 1, page_index->page_data, page_index->page_len);

        ctl_set_success(ctsio);
        ctsio->io_hdr.flags |= CTL_FLAG_ALLOCATED;
        ctsio->be_move_done = ctl_config_move_done;
        ctl_datamove((union ctl_io *)ctsio);
        return (CTL_RETVAL_COMPLETE);
}

int
ctl_read_capacity(struct ctl_scsiio *ctsio)
{
        struct ctl_lun *lun = CTL_LUN(ctsio);
        struct scsi_read_capacity *cdb;
        struct scsi_read_capacity_data *data;
        uint32_t lba;

        CTL_DEBUG_PRINT(("ctl_read_capacity\n"));

        cdb = (struct scsi_read_capacity *)ctsio->cdb;

        lba = scsi_4btoul(cdb->addr);
        if (((cdb->pmi & SRC_PMI) == 0)
         && (lba != 0)) {
                ctl_set_invalid_field(/*ctsio*/ ctsio,
                                      /*sks_valid*/ 1,
                                      /*command*/ 1,
                                      /*field*/ 2,
                                      /*bit_valid*/ 0,
                                      /*bit*/ 0);
                ctl_done((union ctl_io *)ctsio);
                return (CTL_RETVAL_COMPLETE);
        }

        ctsio->kern_data_ptr = malloc(sizeof(*data), M_CTL, M_WAITOK | M_ZERO);
        data = (struct scsi_read_capacity_data *)ctsio->kern_data_ptr;
        ctsio->kern_data_len = sizeof(*data);
        ctsio->kern_total_len = sizeof(*data);
        ctsio->kern_rel_offset = 0;
        ctsio->kern_sg_entries = 0;

        /*
         * If the maximum LBA is greater than 0xfffffffe, the user must
         * issue a SERVICE ACTION IN (16) command, with the read capacity
         * serivce action set.
         */
        if (lun->be_lun->maxlba > 0xfffffffe)
                scsi_ulto4b(0xffffffff, data->addr);
        else
                scsi_ulto4b(lun->be_lun->maxlba, data->addr);

        /*
         * XXX KDM this may not be 512 bytes...
         */
        scsi_ulto4b(lun->be_lun->blocksize, data->length);

        ctl_set_success(ctsio);
        ctsio->io_hdr.flags |= CTL_FLAG_ALLOCATED;
        ctsio->be_move_done = ctl_config_move_done;
        ctl_datamove((union ctl_io *)ctsio);
        return (CTL_RETVAL_COMPLETE);
}

int
ctl_read_capacity_16(struct ctl_scsiio *ctsio)
{
        struct ctl_lun *lun = CTL_LUN(ctsio);
        struct scsi_read_capacity_16 *cdb;
        struct scsi_read_capacity_data_long *data;
        uint64_t lba;
        uint32_t alloc_len;

        CTL_DEBUG_PRINT(("ctl_read_capacity_16\n"));

        cdb = (struct scsi_read_capacity_16 *)ctsio->cdb;

        alloc_len = scsi_4btoul(cdb->alloc_len);
        lba = scsi_8btou64(cdb->addr);

        if ((cdb->reladr & SRC16_PMI)
         && (lba != 0)) {
                ctl_set_invalid_field(/*ctsio*/ ctsio,
                                      /*sks_valid*/ 1,
                                      /*command*/ 1,
                                      /*field*/ 2,
                                      /*bit_valid*/ 0,
                                      /*bit*/ 0);
                ctl_done((union ctl_io *)ctsio);
                return (CTL_RETVAL_COMPLETE);
        }

        ctsio->kern_data_ptr = malloc(sizeof(*data), M_CTL, M_WAITOK | M_ZERO);
        data = (struct scsi_read_capacity_data_long *)ctsio->kern_data_ptr;
        ctsio->kern_rel_offset = 0;
        ctsio->kern_sg_entries = 0;
        ctsio->kern_data_len = min(sizeof(*data), alloc_len);
        ctsio->kern_total_len = ctsio->kern_data_len;

        scsi_u64to8b(lun->be_lun->maxlba, data->addr);
        /* XXX KDM this may not be 512 bytes... */
        scsi_ulto4b(lun->be_lun->blocksize, data->length);
        data->prot_lbppbe = lun->be_lun->pblockexp & SRC16_LBPPBE;
        scsi_ulto2b(lun->be_lun->pblockoff & SRC16_LALBA_A, data->lalba_lbp);
        if (lun->be_lun->flags & CTL_LUN_FLAG_UNMAP)
                data->lalba_lbp[0] |= SRC16_LBPME | SRC16_LBPRZ;

        ctl_set_success(ctsio);
        ctsio->io_hdr.flags |= CTL_FLAG_ALLOCATED;
        ctsio->be_move_done = ctl_config_move_done;
        ctl_datamove((union ctl_io *)ctsio);
        return (CTL_RETVAL_COMPLETE);
}

int
ctl_get_lba_status(struct ctl_scsiio *ctsio)
{
        struct ctl_lun *lun = CTL_LUN(ctsio);
        struct scsi_get_lba_status *cdb;
        struct scsi_get_lba_status_data *data;
        struct ctl_lba_len_flags *lbalen;
        uint64_t lba;
        uint32_t alloc_len, total_len;
        int retval;

        CTL_DEBUG_PRINT(("ctl_get_lba_status\n"));

        cdb = (struct scsi_get_lba_status *)ctsio->cdb;
        lba = scsi_8btou64(cdb->addr);
        alloc_len = scsi_4btoul(cdb->alloc_len);

        if (lba > lun->be_lun->maxlba) {
                ctl_set_lba_out_of_range(ctsio, lba);
                ctl_done((union ctl_io *)ctsio);
                return (CTL_RETVAL_COMPLETE);
        }

        total_len = sizeof(*data) + sizeof(data->descr[0]);
        ctsio->kern_data_ptr = malloc(total_len, M_CTL, M_WAITOK | M_ZERO);
        data = (struct scsi_get_lba_status_data *)ctsio->kern_data_ptr;
        ctsio->kern_rel_offset = 0;
        ctsio->kern_sg_entries = 0;
        ctsio->kern_data_len = min(total_len, alloc_len);
        ctsio->kern_total_len = ctsio->kern_data_len;

        /* Fill dummy data in case backend can't tell anything. */
        scsi_ulto4b(4 + sizeof(data->descr[0]), data->length);
        scsi_u64to8b(lba, data->descr[0].addr);
        scsi_ulto4b(MIN(UINT32_MAX, lun->be_lun->maxlba + 1 - lba),
            data->descr[0].length);
        data->descr[0].status = 0; /* Mapped or unknown. */

        ctl_set_success(ctsio);
        ctsio->io_hdr.flags |= CTL_FLAG_ALLOCATED;
        ctsio->be_move_done = ctl_config_move_done;

        lbalen = (struct ctl_lba_len_flags *)&ctsio->io_hdr.ctl_private[CTL_PRIV_LBA_LEN];
        lbalen->lba = lba;
        lbalen->len = total_len;
        lbalen->flags = 0;
        retval = lun->backend->config_read((union ctl_io *)ctsio);
        return (retval);
}

int
ctl_read_defect(struct ctl_scsiio *ctsio)
{
        struct scsi_read_defect_data_10 *ccb10;
        struct scsi_read_defect_data_12 *ccb12;
        struct scsi_read_defect_data_hdr_10 *data10;
        struct scsi_read_defect_data_hdr_12 *data12;
        uint32_t alloc_len, data_len;
        uint8_t format;

        CTL_DEBUG_PRINT(("ctl_read_defect\n"));

        if (ctsio->cdb[0] == READ_DEFECT_DATA_10) {
                ccb10 = (struct scsi_read_defect_data_10 *)&ctsio->cdb;
                format = ccb10->format;
                alloc_len = scsi_2btoul(ccb10->alloc_length);
                data_len = sizeof(*data10);
        } else {
                ccb12 = (struct scsi_read_defect_data_12 *)&ctsio->cdb;
                format = ccb12->format;
                alloc_len = scsi_4btoul(ccb12->alloc_length);
                data_len = sizeof(*data12);
        }
        if (alloc_len == 0) {
                ctl_set_success(ctsio);
                ctl_done((union ctl_io *)ctsio);
                return (CTL_RETVAL_COMPLETE);
        }

        ctsio->kern_data_ptr = malloc(data_len, M_CTL, M_WAITOK | M_ZERO);
        ctsio->kern_rel_offset = 0;
        ctsio->kern_sg_entries = 0;
        ctsio->kern_data_len = min(data_len, alloc_len);
        ctsio->kern_total_len = ctsio->kern_data_len;

        if (ctsio->cdb[0] == READ_DEFECT_DATA_10) {
                data10 = (struct scsi_read_defect_data_hdr_10 *)
                    ctsio->kern_data_ptr;
                data10->format = format;
                scsi_ulto2b(0, data10->length);
        } else {
                data12 = (struct scsi_read_defect_data_hdr_12 *)
                    ctsio->kern_data_ptr;
                data12->format = format;
                scsi_ulto2b(0, data12->generation);
                scsi_ulto4b(0, data12->length);
        }

        ctl_set_success(ctsio);
        ctsio->io_hdr.flags |= CTL_FLAG_ALLOCATED;
        ctsio->be_move_done = ctl_config_move_done;
        ctl_datamove((union ctl_io *)ctsio);
        return (CTL_RETVAL_COMPLETE);
}

int
ctl_report_tagret_port_groups(struct ctl_scsiio *ctsio)
{
        struct ctl_softc *softc = CTL_SOFTC(ctsio);
        struct ctl_lun *lun = CTL_LUN(ctsio);
        struct scsi_maintenance_in *cdb;
        int retval;
        int alloc_len, ext, total_len = 0, g, pc, pg, ts, os;
        int num_ha_groups, num_target_ports, shared_group;
        struct ctl_port *port;
        struct scsi_target_group_data *rtg_ptr;
        struct scsi_target_group_data_extended *rtg_ext_ptr;
        struct scsi_target_port_group_descriptor *tpg_desc;

        CTL_DEBUG_PRINT(("ctl_report_tagret_port_groups\n"));

        cdb = (struct scsi_maintenance_in *)ctsio->cdb;
        retval = CTL_RETVAL_COMPLETE;

        switch (cdb->byte2 & STG_PDF_MASK) {
        case STG_PDF_LENGTH:
                ext = 0;
                break;
        case STG_PDF_EXTENDED:
                ext = 1;
                break;
        default:
                ctl_set_invalid_field(/*ctsio*/ ctsio,
                                      /*sks_valid*/ 1,
                                      /*command*/ 1,
                                      /*field*/ 2,
                                      /*bit_valid*/ 1,
                                      /*bit*/ 5);
                ctl_done((union ctl_io *)ctsio);
                return(retval);
        }

        num_target_ports = 0;
        shared_group = (softc->is_single != 0);
        mtx_lock(&softc->ctl_lock);
        STAILQ_FOREACH(port, &softc->port_list, links) {
                if ((port->status & CTL_PORT_STATUS_ONLINE) == 0)
                        continue;
                if (ctl_lun_map_to_port(port, lun->lun) == UINT32_MAX)
                        continue;
                num_target_ports++;
                if (port->status & CTL_PORT_STATUS_HA_SHARED)
                        shared_group = 1;
        }
        mtx_unlock(&softc->ctl_lock);
        num_ha_groups = (softc->is_single) ? 0 : NUM_HA_SHELVES;

        if (ext)
                total_len = sizeof(struct scsi_target_group_data_extended);
        else
                total_len = sizeof(struct scsi_target_group_data);
        total_len += sizeof(struct scsi_target_port_group_descriptor) *
                (shared_group + num_ha_groups) +
            sizeof(struct scsi_target_port_descriptor) * num_target_ports;

        alloc_len = scsi_4btoul(cdb->length);

        ctsio->kern_data_ptr = malloc(total_len, M_CTL, M_WAITOK | M_ZERO);
        ctsio->kern_sg_entries = 0;
        ctsio->kern_rel_offset = 0;
        ctsio->kern_data_len = min(total_len, alloc_len);
        ctsio->kern_total_len = ctsio->kern_data_len;

        if (ext) {
                rtg_ext_ptr = (struct scsi_target_group_data_extended *)
                    ctsio->kern_data_ptr;
                scsi_ulto4b(total_len - 4, rtg_ext_ptr->length);
                rtg_ext_ptr->format_type = 0x10;
                rtg_ext_ptr->implicit_transition_time = 0;
                tpg_desc = &rtg_ext_ptr->groups[0];
        } else {
                rtg_ptr = (struct scsi_target_group_data *)
                    ctsio->kern_data_ptr;
                scsi_ulto4b(total_len - 4, rtg_ptr->length);
                tpg_desc = &rtg_ptr->groups[0];
        }

        mtx_lock(&softc->ctl_lock);
        pg = softc->port_min / softc->port_cnt;
        if (lun->flags & (CTL_LUN_PRIMARY_SC | CTL_LUN_PEER_SC_PRIMARY)) {
                /* Some shelf is known to be primary. */
                if (softc->ha_link == CTL_HA_LINK_OFFLINE)
                        os = TPG_ASYMMETRIC_ACCESS_UNAVAILABLE;
                else if (softc->ha_link == CTL_HA_LINK_UNKNOWN)
                        os = TPG_ASYMMETRIC_ACCESS_TRANSITIONING;
                else if (softc->ha_mode == CTL_HA_MODE_ACT_STBY)
                        os = TPG_ASYMMETRIC_ACCESS_STANDBY;
                else
                        os = TPG_ASYMMETRIC_ACCESS_NONOPTIMIZED;
                if (lun->flags & CTL_LUN_PRIMARY_SC) {
                        ts = TPG_ASYMMETRIC_ACCESS_OPTIMIZED;
                } else {
                        ts = os;
                        os = TPG_ASYMMETRIC_ACCESS_OPTIMIZED;
                }
        } else {
                /* No known primary shelf. */
                if (softc->ha_link == CTL_HA_LINK_OFFLINE) {
                        ts = TPG_ASYMMETRIC_ACCESS_UNAVAILABLE;
                        os = TPG_ASYMMETRIC_ACCESS_OPTIMIZED;
                } else if (softc->ha_link == CTL_HA_LINK_UNKNOWN) {
                        ts = TPG_ASYMMETRIC_ACCESS_TRANSITIONING;
                        os = TPG_ASYMMETRIC_ACCESS_OPTIMIZED;
                } else {
                        ts = os = TPG_ASYMMETRIC_ACCESS_TRANSITIONING;
                }
        }
        if (shared_group) {
                tpg_desc->pref_state = ts;
                tpg_desc->support = TPG_AO_SUP | TPG_AN_SUP | TPG_S_SUP |
                    TPG_U_SUP | TPG_T_SUP;
                scsi_ulto2b(1, tpg_desc->target_port_group);
                tpg_desc->status = TPG_IMPLICIT;
                pc = 0;
                STAILQ_FOREACH(port, &softc->port_list, links) {
                        if ((port->status & CTL_PORT_STATUS_ONLINE) == 0)
                                continue;
                        if (!softc->is_single &&
                            (port->status & CTL_PORT_STATUS_HA_SHARED) == 0)
                                continue;
                        if (ctl_lun_map_to_port(port, lun->lun) == UINT32_MAX)
                                continue;
                        scsi_ulto2b(port->targ_port, tpg_desc->descriptors[pc].
                            relative_target_port_identifier);
                        pc++;
                }
                tpg_desc->target_port_count = pc;
                tpg_desc = (struct scsi_target_port_group_descriptor *)
                    &tpg_desc->descriptors[pc];
        }
        for (g = 0; g < num_ha_groups; g++) {
                tpg_desc->pref_state = (g == pg) ? ts : os;
                tpg_desc->support = TPG_AO_SUP | TPG_AN_SUP | TPG_S_SUP |
                    TPG_U_SUP | TPG_T_SUP;
                scsi_ulto2b(2 + g, tpg_desc->target_port_group);
                tpg_desc->status = TPG_IMPLICIT;
                pc = 0;
                STAILQ_FOREACH(port, &softc->port_list, links) {
                        if (port->targ_port < g * softc->port_cnt ||
                            port->targ_port >= (g + 1) * softc->port_cnt)
                                continue;
                        if ((port->status & CTL_PORT_STATUS_ONLINE) == 0)
                                continue;
                        if (port->status & CTL_PORT_STATUS_HA_SHARED)
                                continue;
                        if (ctl_lun_map_to_port(port, lun->lun) == UINT32_MAX)
                                continue;
                        scsi_ulto2b(port->targ_port, tpg_desc->descriptors[pc].
                            relative_target_port_identifier);
                        pc++;
                }
                tpg_desc->target_port_count = pc;
                tpg_desc = (struct scsi_target_port_group_descriptor *)
                    &tpg_desc->descriptors[pc];
        }
        mtx_unlock(&softc->ctl_lock);

        ctl_set_success(ctsio);
        ctsio->io_hdr.flags |= CTL_FLAG_ALLOCATED;
        ctsio->be_move_done = ctl_config_move_done;
        ctl_datamove((union ctl_io *)ctsio);
        return(retval);
}

int
ctl_report_supported_opcodes(struct ctl_scsiio *ctsio)
{
        struct ctl_lun *lun = CTL_LUN(ctsio);
        struct scsi_report_supported_opcodes *cdb;
        const struct ctl_cmd_entry *entry, *sentry;
        struct scsi_report_supported_opcodes_all *all;
        struct scsi_report_supported_opcodes_descr *descr;
        struct scsi_report_supported_opcodes_one *one;
        int retval;
        int alloc_len, total_len;
        int opcode, service_action, i, j, num;

        CTL_DEBUG_PRINT(("ctl_report_supported_opcodes\n"));

        cdb = (struct scsi_report_supported_opcodes *)ctsio->cdb;
        retval = CTL_RETVAL_COMPLETE;

        opcode = cdb->requested_opcode;
        service_action = scsi_2btoul(cdb->requested_service_action);
        switch (cdb->options & RSO_OPTIONS_MASK) {
        case RSO_OPTIONS_ALL:
                num = 0;
                for (i = 0; i < 256; i++) {
                        entry = &ctl_cmd_table[i];
                        if (entry->flags & CTL_CMD_FLAG_SA5) {
                                for (j = 0; j < 32; j++) {
                                        sentry = &((const struct ctl_cmd_entry *)
                                            entry->execute)[j];
                                        if (ctl_cmd_applicable(
                                            lun->be_lun->lun_type, sentry))
                                                num++;
                                }
                        } else {
                                if (ctl_cmd_applicable(lun->be_lun->lun_type,
                                    entry))
                                        num++;
                        }
                }
                total_len = sizeof(struct scsi_report_supported_opcodes_all) +
                    num * sizeof(struct scsi_report_supported_opcodes_descr);
                break;
        case RSO_OPTIONS_OC:
                if (ctl_cmd_table[opcode].flags & CTL_CMD_FLAG_SA5) {
                        ctl_set_invalid_field(/*ctsio*/ ctsio,
                                              /*sks_valid*/ 1,
                                              /*command*/ 1,
                                              /*field*/ 2,
                                              /*bit_valid*/ 1,
                                              /*bit*/ 2);
                        ctl_done((union ctl_io *)ctsio);
                        return (CTL_RETVAL_COMPLETE);
                }
                total_len = sizeof(struct scsi_report_supported_opcodes_one) + 32;
                break;
        case RSO_OPTIONS_OC_SA:
                if ((ctl_cmd_table[opcode].flags & CTL_CMD_FLAG_SA5) == 0 ||
                    service_action >= 32) {
                        ctl_set_invalid_field(/*ctsio*/ ctsio,
                                              /*sks_valid*/ 1,
                                              /*command*/ 1,
                                              /*field*/ 2,
                                              /*bit_valid*/ 1,
                                              /*bit*/ 2);
                        ctl_done((union ctl_io *)ctsio);
                        return (CTL_RETVAL_COMPLETE);
                }
                /* FALLTHROUGH */
        case RSO_OPTIONS_OC_ASA:
                total_len = sizeof(struct scsi_report_supported_opcodes_one) + 32;
                break;
        default:
                ctl_set_invalid_field(/*ctsio*/ ctsio,
                                      /*sks_valid*/ 1,
                                      /*command*/ 1,
                                      /*field*/ 2,
                                      /*bit_valid*/ 1,
                                      /*bit*/ 2);
                ctl_done((union ctl_io *)ctsio);
                return (CTL_RETVAL_COMPLETE);
        }

        alloc_len = scsi_4btoul(cdb->length);

        ctsio->kern_data_ptr = malloc(total_len, M_CTL, M_WAITOK | M_ZERO);
        ctsio->kern_sg_entries = 0;
        ctsio->kern_rel_offset = 0;
        ctsio->kern_data_len = min(total_len, alloc_len);
        ctsio->kern_total_len = ctsio->kern_data_len;

        switch (cdb->options & RSO_OPTIONS_MASK) {
        case RSO_OPTIONS_ALL:
                all = (struct scsi_report_supported_opcodes_all *)
                    ctsio->kern_data_ptr;
                num = 0;
                for (i = 0; i < 256; i++) {
                        entry = &ctl_cmd_table[i];
                        if (entry->flags & CTL_CMD_FLAG_SA5) {
                                for (j = 0; j < 32; j++) {
                                        sentry = &((const struct ctl_cmd_entry *)
                                            entry->execute)[j];
                                        if (!ctl_cmd_applicable(
                                            lun->be_lun->lun_type, sentry))
                                                continue;
                                        descr = &all->descr[num++];
                                        descr->opcode = i;
                                        scsi_ulto2b(j, descr->service_action);
                                        descr->flags = RSO_SERVACTV;
                                        scsi_ulto2b(sentry->length,
                                            descr->cdb_length);
                                }
                        } else {
                                if (!ctl_cmd_applicable(lun->be_lun->lun_type,
                                    entry))
                                        continue;
                                descr = &all->descr[num++];
                                descr->opcode = i;
                                scsi_ulto2b(0, descr->service_action);
                                descr->flags = 0;
                                scsi_ulto2b(entry->length, descr->cdb_length);
                        }
                }
                scsi_ulto4b(
                    num * sizeof(struct scsi_report_supported_opcodes_descr),
                    all->length);
                break;
        case RSO_OPTIONS_OC:
                one = (struct scsi_report_supported_opcodes_one *)
                    ctsio->kern_data_ptr;
                entry = &ctl_cmd_table[opcode];
                goto fill_one;
        case RSO_OPTIONS_OC_SA:
                one = (struct scsi_report_supported_opcodes_one *)
                    ctsio->kern_data_ptr;
                entry = &ctl_cmd_table[opcode];
                entry = &((const struct ctl_cmd_entry *)
                    entry->execute)[service_action];
fill_one:
                if (ctl_cmd_applicable(lun->be_lun->lun_type, entry)) {
                        one->support = 3;
                        scsi_ulto2b(entry->length, one->cdb_length);
                        one->cdb_usage[0] = opcode;
                        memcpy(&one->cdb_usage[1], entry->usage,
                            entry->length - 1);
                } else
                        one->support = 1;
                break;
        case RSO_OPTIONS_OC_ASA:
                one = (struct scsi_report_supported_opcodes_one *)
                    ctsio->kern_data_ptr;
                entry = &ctl_cmd_table[opcode];
                if (entry->flags & CTL_CMD_FLAG_SA5) {
                        entry = &((const struct ctl_cmd_entry *)
                            entry->execute)[service_action];
                } else if (service_action != 0) {
                        one->support = 1;
                        break;
                }
                goto fill_one;
        }

        ctl_set_success(ctsio);
        ctsio->io_hdr.flags |= CTL_FLAG_ALLOCATED;
        ctsio->be_move_done = ctl_config_move_done;
        ctl_datamove((union ctl_io *)ctsio);
        return(retval);
}

int
ctl_report_supported_tmf(struct ctl_scsiio *ctsio)
{
        struct scsi_report_supported_tmf *cdb;
        struct scsi_report_supported_tmf_ext_data *data;
        int retval;
        int alloc_len, total_len;

        CTL_DEBUG_PRINT(("ctl_report_supported_tmf\n"));

        cdb = (struct scsi_report_supported_tmf *)ctsio->cdb;

        retval = CTL_RETVAL_COMPLETE;

        if (cdb->options & RST_REPD)
                total_len = sizeof(struct scsi_report_supported_tmf_ext_data);
        else
                total_len = sizeof(struct scsi_report_supported_tmf_data);
        alloc_len = scsi_4btoul(cdb->length);

        ctsio->kern_data_ptr = malloc(total_len, M_CTL, M_WAITOK | M_ZERO);
        ctsio->kern_sg_entries = 0;
        ctsio->kern_rel_offset = 0;
        ctsio->kern_data_len = min(total_len, alloc_len);
        ctsio->kern_total_len = ctsio->kern_data_len;

        data = (struct scsi_report_supported_tmf_ext_data *)ctsio->kern_data_ptr;
        data->byte1 |= RST_ATS | RST_ATSS | RST_CTSS | RST_LURS | RST_QTS |
            RST_TRS;
        data->byte2 |= RST_QAES | RST_QTSS | RST_ITNRS;
        data->length = total_len - 4;

        ctl_set_success(ctsio);
        ctsio->io_hdr.flags |= CTL_FLAG_ALLOCATED;
        ctsio->be_move_done = ctl_config_move_done;
        ctl_datamove((union ctl_io *)ctsio);
        return (retval);
}

int
ctl_report_timestamp(struct ctl_scsiio *ctsio)
{
        struct scsi_report_timestamp *cdb;
        struct scsi_report_timestamp_data *data;
        struct timeval tv;
        int64_t timestamp;
        int retval;
        int alloc_len, total_len;

        CTL_DEBUG_PRINT(("ctl_report_timestamp\n"));

        cdb = (struct scsi_report_timestamp *)ctsio->cdb;

        retval = CTL_RETVAL_COMPLETE;

        total_len = sizeof(struct scsi_report_timestamp_data);
        alloc_len = scsi_4btoul(cdb->length);

        ctsio->kern_data_ptr = malloc(total_len, M_CTL, M_WAITOK | M_ZERO);
        ctsio->kern_sg_entries = 0;
        ctsio->kern_rel_offset = 0;
        ctsio->kern_data_len = min(total_len, alloc_len);
        ctsio->kern_total_len = ctsio->kern_data_len;

        data = (struct scsi_report_timestamp_data *)ctsio->kern_data_ptr;
        scsi_ulto2b(sizeof(*data) - 2, data->length);
        data->origin = RTS_ORIG_OUTSIDE;
        getmicrotime(&tv);
        timestamp = (int64_t)tv.tv_sec * 1000 + tv.tv_usec / 1000;
        scsi_ulto4b(timestamp >> 16, data->timestamp);
        scsi_ulto2b(timestamp & 0xffff, &data->timestamp[4]);

        ctl_set_success(ctsio);
        ctsio->io_hdr.flags |= CTL_FLAG_ALLOCATED;
        ctsio->be_move_done = ctl_config_move_done;
        ctl_datamove((union ctl_io *)ctsio);
        return (retval);
}

int
ctl_persistent_reserve_in(struct ctl_scsiio *ctsio)
{
        struct ctl_softc *softc = CTL_SOFTC(ctsio);
        struct ctl_lun *lun = CTL_LUN(ctsio);
        struct scsi_per_res_in *cdb;
        int alloc_len, total_len = 0;
        /* struct scsi_per_res_in_rsrv in_data; */
        uint64_t key;

        CTL_DEBUG_PRINT(("ctl_persistent_reserve_in\n"));

        cdb = (struct scsi_per_res_in *)ctsio->cdb;

        alloc_len = scsi_2btoul(cdb->length);

retry:
        mtx_lock(&lun->lun_lock);
        switch (cdb->action) {
        case SPRI_RK: /* read keys */
                total_len = sizeof(struct scsi_per_res_in_keys) +
                        lun->pr_key_count *
                        sizeof(struct scsi_per_res_key);
                break;
        case SPRI_RR: /* read reservation */
                if (lun->flags & CTL_LUN_PR_RESERVED)
                        total_len = sizeof(struct scsi_per_res_in_rsrv);
                else
                        total_len = sizeof(struct scsi_per_res_in_header);
                break;
        case SPRI_RC: /* report capabilities */
                total_len = sizeof(struct scsi_per_res_cap);
                break;
        case SPRI_RS: /* read full status */
                total_len = sizeof(struct scsi_per_res_in_header) +
                    (sizeof(struct scsi_per_res_in_full_desc) + 256) *
                    lun->pr_key_count;
                break;
        default:
                panic("%s: Invalid PR type %#x", __func__, cdb->action);
        }
        mtx_unlock(&lun->lun_lock);

        ctsio->kern_data_ptr = malloc(total_len, M_CTL, M_WAITOK | M_ZERO);
        ctsio->kern_rel_offset = 0;
        ctsio->kern_sg_entries = 0;
        ctsio->kern_data_len = min(total_len, alloc_len);
        ctsio->kern_total_len = ctsio->kern_data_len;

        mtx_lock(&lun->lun_lock);
        switch (cdb->action) {
        case SPRI_RK: { // read keys
        struct scsi_per_res_in_keys *res_keys;
                int i, key_count;

                res_keys = (struct scsi_per_res_in_keys*)ctsio->kern_data_ptr;

                /*
                 * We had to drop the lock to allocate our buffer, which
                 * leaves time for someone to come in with another
                 * persistent reservation.  (That is unlikely, though,
                 * since this should be the only persistent reservation
                 * command active right now.)
                 */
                if (total_len != (sizeof(struct scsi_per_res_in_keys) +
                    (lun->pr_key_count *
                     sizeof(struct scsi_per_res_key)))){
                        mtx_unlock(&lun->lun_lock);
                        free(ctsio->kern_data_ptr, M_CTL);
                        printf("%s: reservation length changed, retrying\n",
                               __func__);
                        goto retry;
                }

                scsi_ulto4b(lun->pr_generation, res_keys->header.generation);

                scsi_ulto4b(sizeof(struct scsi_per_res_key) *
                             lun->pr_key_count, res_keys->header.length);

                for (i = 0, key_count = 0; i < CTL_MAX_INITIATORS; i++) {
                        if ((key = ctl_get_prkey(lun, i)) == 0)
                                continue;

                        /*
                         * We used lun->pr_key_count to calculate the
                         * size to allocate.  If it turns out the number of
                         * initiators with the registered flag set is
                         * larger than that (i.e. they haven't been kept in
                         * sync), we've got a problem.
                         */
                        if (key_count >= lun->pr_key_count) {
                                key_count++;
                                continue;
                        }
                        scsi_u64to8b(key, res_keys->keys[key_count].key);
                        key_count++;
                }
                break;
        }
        case SPRI_RR: { // read reservation
                struct scsi_per_res_in_rsrv *res;
                int tmp_len, header_only;

                res = (struct scsi_per_res_in_rsrv *)ctsio->kern_data_ptr;

                scsi_ulto4b(lun->pr_generation, res->header.generation);

                if (lun->flags & CTL_LUN_PR_RESERVED)
                {
                        tmp_len = sizeof(struct scsi_per_res_in_rsrv);
                        scsi_ulto4b(sizeof(struct scsi_per_res_in_rsrv_data),
                                    res->header.length);
                        header_only = 0;
                } else {
                        tmp_len = sizeof(struct scsi_per_res_in_header);
                        scsi_ulto4b(0, res->header.length);
                        header_only = 1;
                }

                /*
                 * We had to drop the lock to allocate our buffer, which
                 * leaves time for someone to come in with another
                 * persistent reservation.  (That is unlikely, though,
                 * since this should be the only persistent reservation
                 * command active right now.)
                 */
                if (tmp_len != total_len) {
                        mtx_unlock(&lun->lun_lock);
                        free(ctsio->kern_data_ptr, M_CTL);
                        printf("%s: reservation status changed, retrying\n",
                               __func__);
                        goto retry;
                }

                /*
                 * No reservation held, so we're done.
                 */
                if (header_only != 0)
                        break;

                /*
                 * If the registration is an All Registrants type, the key
                 * is 0, since it doesn't really matter.
                 */
                if (lun->pr_res_idx != CTL_PR_ALL_REGISTRANTS) {
                        scsi_u64to8b(ctl_get_prkey(lun, lun->pr_res_idx),
                            res->data.reservation);
                }
                res->data.scopetype = lun->pr_res_type;
                break;
        }
        case SPRI_RC:     //report capabilities
        {
                struct scsi_per_res_cap *res_cap;
                uint16_t type_mask;

                res_cap = (struct scsi_per_res_cap *)ctsio->kern_data_ptr;
                scsi_ulto2b(sizeof(*res_cap), res_cap->length);
                res_cap->flags1 = SPRI_CRH;
                res_cap->flags2 = SPRI_TMV | SPRI_ALLOW_5;
                type_mask = SPRI_TM_WR_EX_AR |
                            SPRI_TM_EX_AC_RO |
                            SPRI_TM_WR_EX_RO |
                            SPRI_TM_EX_AC |
                            SPRI_TM_WR_EX |
                            SPRI_TM_EX_AC_AR;
                scsi_ulto2b(type_mask, res_cap->type_mask);
                break;
        }
        case SPRI_RS: { // read full status
                struct scsi_per_res_in_full *res_status;
                struct scsi_per_res_in_full_desc *res_desc;
                struct ctl_port *port;
                int i, len;

                res_status = (struct scsi_per_res_in_full*)ctsio->kern_data_ptr;

                /*
                 * We had to drop the lock to allocate our buffer, which
                 * leaves time for someone to come in with another
                 * persistent reservation.  (That is unlikely, though,
                 * since this should be the only persistent reservation
                 * command active right now.)
                 */
                if (total_len < (sizeof(struct scsi_per_res_in_header) +
                    (sizeof(struct scsi_per_res_in_full_desc) + 256) *
                     lun->pr_key_count)){
                        mtx_unlock(&lun->lun_lock);
                        free(ctsio->kern_data_ptr, M_CTL);
                        printf("%s: reservation length changed, retrying\n",
                               __func__);
                        goto retry;
                }

                scsi_ulto4b(lun->pr_generation, res_status->header.generation);

                res_desc = &res_status->desc[0];
                for (i = 0; i < CTL_MAX_INITIATORS; i++) {
                        if ((key = ctl_get_prkey(lun, i)) == 0)
                                continue;

                        scsi_u64to8b(key, res_desc->res_key.key);
                        if ((lun->flags & CTL_LUN_PR_RESERVED) &&
                            (lun->pr_res_idx == i ||
                             lun->pr_res_idx == CTL_PR_ALL_REGISTRANTS)) {
                                res_desc->flags = SPRI_FULL_R_HOLDER;
                                res_desc->scopetype = lun->pr_res_type;
                        }
                        scsi_ulto2b(i / CTL_MAX_INIT_PER_PORT,
                            res_desc->rel_trgt_port_id);
                        len = 0;
                        port = softc->ctl_ports[i / CTL_MAX_INIT_PER_PORT];
                        if (port != NULL)
                                len = ctl_create_iid(port,
                                    i % CTL_MAX_INIT_PER_PORT,
                                    res_desc->transport_id);
                        scsi_ulto4b(len, res_desc->additional_length);
                        res_desc = (struct scsi_per_res_in_full_desc *)
                            &res_desc->transport_id[len];
                }
                scsi_ulto4b((uint8_t *)res_desc - (uint8_t *)&res_status->desc[0],
                    res_status->header.length);
                break;
        }
        default:
                panic("%s: Invalid PR type %#x", __func__, cdb->action);
        }
        mtx_unlock(&lun->lun_lock);

        ctl_set_success(ctsio);
        ctsio->io_hdr.flags |= CTL_FLAG_ALLOCATED;
        ctsio->be_move_done = ctl_config_move_done;
        ctl_datamove((union ctl_io *)ctsio);
        return (CTL_RETVAL_COMPLETE);
}

/*
 * Returns 0 if ctl_persistent_reserve_out() should continue, non-zero if
 * it should return.
 */
static int
ctl_pro_preempt(struct ctl_softc *softc, struct ctl_lun *lun, uint64_t res_key,
                uint64_t sa_res_key, uint8_t type, uint32_t residx,
                struct ctl_scsiio *ctsio, struct scsi_per_res_out *cdb,
                struct scsi_per_res_out_parms* param)
{
        union ctl_ha_msg persis_io;
        int i;

        mtx_lock(&lun->lun_lock);
        if (sa_res_key == 0) {
                if (lun->pr_res_idx == CTL_PR_ALL_REGISTRANTS) {
                        /* validate scope and type */
                        if ((cdb->scope_type & SPR_SCOPE_MASK) !=
                             SPR_LU_SCOPE) {
                                mtx_unlock(&lun->lun_lock);
                                ctl_set_invalid_field(/*ctsio*/ ctsio,
                                                      /*sks_valid*/ 1,
                                                      /*command*/ 1,
                                                      /*field*/ 2,
                                                      /*bit_valid*/ 1,
                                                      /*bit*/ 4);
                                ctl_done((union ctl_io *)ctsio);
                                return (1);
                        }

                        if (type>8 || type==2 || type==4 || type==0) {
                                mtx_unlock(&lun->lun_lock);
                                ctl_set_invalid_field(/*ctsio*/ ctsio,
                                                      /*sks_valid*/ 1,
                                                      /*command*/ 1,
                                                      /*field*/ 2,
                                                      /*bit_valid*/ 1,
                                                      /*bit*/ 0);
                                ctl_done((union ctl_io *)ctsio);
                                return (1);
                        }

                        /*
                         * Unregister everybody else and build UA for
                         * them
                         */
                        for(i = 0; i < CTL_MAX_INITIATORS; i++) {
                                if (i == residx || ctl_get_prkey(lun, i) == 0)
                                        continue;

                                ctl_clr_prkey(lun, i);
                                ctl_est_ua(lun, i, CTL_UA_REG_PREEMPT);
                        }
                        lun->pr_key_count = 1;
                        lun->pr_res_type = type;
                        if (lun->pr_res_type != SPR_TYPE_WR_EX_AR &&
                            lun->pr_res_type != SPR_TYPE_EX_AC_AR)
                                lun->pr_res_idx = residx;
                        lun->pr_generation++;
                        mtx_unlock(&lun->lun_lock);

                        /* send msg to other side */
                        persis_io.hdr.nexus = ctsio->io_hdr.nexus;
                        persis_io.hdr.msg_type = CTL_MSG_PERS_ACTION;
                        persis_io.pr.pr_info.action = CTL_PR_PREEMPT;
                        persis_io.pr.pr_info.residx = lun->pr_res_idx;
                        persis_io.pr.pr_info.res_type = type;
                        memcpy(persis_io.pr.pr_info.sa_res_key,
                               param->serv_act_res_key,
                               sizeof(param->serv_act_res_key));
                        ctl_ha_msg_send(CTL_HA_CHAN_CTL, &persis_io,
                            sizeof(persis_io.pr), M_WAITOK);
                } else {
                        /* not all registrants */
                        mtx_unlock(&lun->lun_lock);
                        free(ctsio->kern_data_ptr, M_CTL);
                        ctl_set_invalid_field(ctsio,
                                              /*sks_valid*/ 1,
                                              /*command*/ 0,
                                              /*field*/ 8,
                                              /*bit_valid*/ 0,
                                              /*bit*/ 0);
                        ctl_done((union ctl_io *)ctsio);
                        return (1);
                }
        } else if (lun->pr_res_idx == CTL_PR_ALL_REGISTRANTS
                || !(lun->flags & CTL_LUN_PR_RESERVED)) {
                int found = 0;

                if (res_key == sa_res_key) {
                        /* special case */
                        /*
                         * The spec implies this is not good but doesn't
                         * say what to do. There are two choices either
                         * generate a res conflict or check condition
                         * with illegal field in parameter data. Since
                         * that is what is done when the sa_res_key is
                         * zero I'll take that approach since this has
                         * to do with the sa_res_key.
                         */
                        mtx_unlock(&lun->lun_lock);
                        free(ctsio->kern_data_ptr, M_CTL);
                        ctl_set_invalid_field(ctsio,
                                              /*sks_valid*/ 1,
                                              /*command*/ 0,
                                              /*field*/ 8,
                                              /*bit_valid*/ 0,
                                              /*bit*/ 0);
                        ctl_done((union ctl_io *)ctsio);
                        return (1);
                }

                for (i = 0; i < CTL_MAX_INITIATORS; i++) {
                        if (ctl_get_prkey(lun, i) != sa_res_key)
                                continue;

                        found = 1;
                        ctl_clr_prkey(lun, i);
                        lun->pr_key_count--;
                        ctl_est_ua(lun, i, CTL_UA_REG_PREEMPT);
                }
                if (!found) {
                        mtx_unlock(&lun->lun_lock);
                        free(ctsio->kern_data_ptr, M_CTL);
                        ctl_set_reservation_conflict(ctsio);
                        ctl_done((union ctl_io *)ctsio);
                        return (CTL_RETVAL_COMPLETE);
                }
                lun->pr_generation++;
                mtx_unlock(&lun->lun_lock);

                /* send msg to other side */
                persis_io.hdr.nexus = ctsio->io_hdr.nexus;
                persis_io.hdr.msg_type = CTL_MSG_PERS_ACTION;
                persis_io.pr.pr_info.action = CTL_PR_PREEMPT;
                persis_io.pr.pr_info.residx = lun->pr_res_idx;
                persis_io.pr.pr_info.res_type = type;
                memcpy(persis_io.pr.pr_info.sa_res_key,
                       param->serv_act_res_key,
                       sizeof(param->serv_act_res_key));
                ctl_ha_msg_send(CTL_HA_CHAN_CTL, &persis_io,
                    sizeof(persis_io.pr), M_WAITOK);
        } else {
                /* Reserved but not all registrants */
                /* sa_res_key is res holder */
                if (sa_res_key == ctl_get_prkey(lun, lun->pr_res_idx)) {
                        /* validate scope and type */
                        if ((cdb->scope_type & SPR_SCOPE_MASK) !=
                             SPR_LU_SCOPE) {
                                mtx_unlock(&lun->lun_lock);
                                ctl_set_invalid_field(/*ctsio*/ ctsio,
                                                      /*sks_valid*/ 1,
                                                      /*command*/ 1,
                                                      /*field*/ 2,
                                                      /*bit_valid*/ 1,
                                                      /*bit*/ 4);
                                ctl_done((union ctl_io *)ctsio);
                                return (1);
                        }

                        if (type>8 || type==2 || type==4 || type==0) {
                                mtx_unlock(&lun->lun_lock);
                                ctl_set_invalid_field(/*ctsio*/ ctsio,
                                                      /*sks_valid*/ 1,
                                                      /*command*/ 1,
                                                      /*field*/ 2,
                                                      /*bit_valid*/ 1,
                                                      /*bit*/ 0);
                                ctl_done((union ctl_io *)ctsio);
                                return (1);
                        }

                        /*
                         * Do the following:
                         * if sa_res_key != res_key remove all
                         * registrants w/sa_res_key and generate UA
                         * for these registrants(Registrations
                         * Preempted) if it wasn't an exclusive
                         * reservation generate UA(Reservations
                         * Preempted) for all other registered nexuses
                         * if the type has changed. Establish the new
                         * reservation and holder. If res_key and
                         * sa_res_key are the same do the above
                         * except don't unregister the res holder.
                         */

                        for(i = 0; i < CTL_MAX_INITIATORS; i++) {
                                if (i == residx || ctl_get_prkey(lun, i) == 0)
                                        continue;

                                if (sa_res_key == ctl_get_prkey(lun, i)) {
                                        ctl_clr_prkey(lun, i);
                                        lun->pr_key_count--;
                                        ctl_est_ua(lun, i, CTL_UA_REG_PREEMPT);
                                } else if (type != lun->pr_res_type &&
                                    (lun->pr_res_type == SPR_TYPE_WR_EX_RO ||
                                     lun->pr_res_type == SPR_TYPE_EX_AC_RO)) {
                                        ctl_est_ua(lun, i, CTL_UA_RES_RELEASE);
                                }
                        }
                        lun->pr_res_type = type;
                        if (lun->pr_res_type != SPR_TYPE_WR_EX_AR &&
                            lun->pr_res_type != SPR_TYPE_EX_AC_AR)
                                lun->pr_res_idx = residx;
                        else
                                lun->pr_res_idx = CTL_PR_ALL_REGISTRANTS;
                        lun->pr_generation++;
                        mtx_unlock(&lun->lun_lock);

                        persis_io.hdr.nexus = ctsio->io_hdr.nexus;
                        persis_io.hdr.msg_type = CTL_MSG_PERS_ACTION;
                        persis_io.pr.pr_info.action = CTL_PR_PREEMPT;
                        persis_io.pr.pr_info.residx = lun->pr_res_idx;
                        persis_io.pr.pr_info.res_type = type;
                        memcpy(persis_io.pr.pr_info.sa_res_key,
                               param->serv_act_res_key,
                               sizeof(param->serv_act_res_key));
                        ctl_ha_msg_send(CTL_HA_CHAN_CTL, &persis_io,
                            sizeof(persis_io.pr), M_WAITOK);
                } else {
                        /*
                         * sa_res_key is not the res holder just
                         * remove registrants
                         */
                        int found=0;

                        for (i = 0; i < CTL_MAX_INITIATORS; i++) {
                                if (sa_res_key != ctl_get_prkey(lun, i))
                                        continue;

                                found = 1;
                                ctl_clr_prkey(lun, i);
                                lun->pr_key_count--;
                                ctl_est_ua(lun, i, CTL_UA_REG_PREEMPT);
                        }

                        if (!found) {
                                mtx_unlock(&lun->lun_lock);
                                free(ctsio->kern_data_ptr, M_CTL);
                                ctl_set_reservation_conflict(ctsio);
                                ctl_done((union ctl_io *)ctsio);
                                return (1);
                        }
                        lun->pr_generation++;
                        mtx_unlock(&lun->lun_lock);

                        persis_io.hdr.nexus = ctsio->io_hdr.nexus;
                        persis_io.hdr.msg_type = CTL_MSG_PERS_ACTION;
                        persis_io.pr.pr_info.action = CTL_PR_PREEMPT;
                        persis_io.pr.pr_info.residx = lun->pr_res_idx;
                        persis_io.pr.pr_info.res_type = type;
                        memcpy(persis_io.pr.pr_info.sa_res_key,
                               param->serv_act_res_key,
                               sizeof(param->serv_act_res_key));
                        ctl_ha_msg_send(CTL_HA_CHAN_CTL, &persis_io,
                            sizeof(persis_io.pr), M_WAITOK);
                }
        }
        return (0);
}

static void
ctl_pro_preempt_other(struct ctl_lun *lun, union ctl_ha_msg *msg)
{
        uint64_t sa_res_key;
        int i;

        sa_res_key = scsi_8btou64(msg->pr.pr_info.sa_res_key);

        if (lun->pr_res_idx == CTL_PR_ALL_REGISTRANTS
         || lun->pr_res_idx == CTL_PR_NO_RESERVATION
         || sa_res_key != ctl_get_prkey(lun, lun->pr_res_idx)) {
                if (sa_res_key == 0) {
                        /*
                         * Unregister everybody else and build UA for
                         * them
                         */
                        for(i = 0; i < CTL_MAX_INITIATORS; i++) {
                                if (i == msg->pr.pr_info.residx ||
                                    ctl_get_prkey(lun, i) == 0)
                                        continue;

                                ctl_clr_prkey(lun, i);
                                ctl_est_ua(lun, i, CTL_UA_REG_PREEMPT);
                        }

                        lun->pr_key_count = 1;
                        lun->pr_res_type = msg->pr.pr_info.res_type;
                        if (lun->pr_res_type != SPR_TYPE_WR_EX_AR &&
                            lun->pr_res_type != SPR_TYPE_EX_AC_AR)
                                lun->pr_res_idx = msg->pr.pr_info.residx;
                } else {
                        for (i = 0; i < CTL_MAX_INITIATORS; i++) {
                                if (sa_res_key == ctl_get_prkey(lun, i))
                                        continue;

                                ctl_clr_prkey(lun, i);
                                lun->pr_key_count--;
                                ctl_est_ua(lun, i, CTL_UA_REG_PREEMPT);
                        }
                }
        } else {
                for (i = 0; i < CTL_MAX_INITIATORS; i++) {
                        if (i == msg->pr.pr_info.residx ||
                            ctl_get_prkey(lun, i) == 0)
                                continue;

                        if (sa_res_key == ctl_get_prkey(lun, i)) {
                                ctl_clr_prkey(lun, i);
                                lun->pr_key_count--;
                                ctl_est_ua(lun, i, CTL_UA_REG_PREEMPT);
                        } else if (msg->pr.pr_info.res_type != lun->pr_res_type
                            && (lun->pr_res_type == SPR_TYPE_WR_EX_RO ||
                             lun->pr_res_type == SPR_TYPE_EX_AC_RO)) {
                                ctl_est_ua(lun, i, CTL_UA_RES_RELEASE);
                        }
                }
                lun->pr_res_type = msg->pr.pr_info.res_type;
                if (lun->pr_res_type != SPR_TYPE_WR_EX_AR &&
                    lun->pr_res_type != SPR_TYPE_EX_AC_AR)
                        lun->pr_res_idx = msg->pr.pr_info.residx;
                else
                        lun->pr_res_idx = CTL_PR_ALL_REGISTRANTS;
        }
        lun->pr_generation++;

}


int
ctl_persistent_reserve_out(struct ctl_scsiio *ctsio)
{
        struct ctl_softc *softc = CTL_SOFTC(ctsio);
        struct ctl_lun *lun = CTL_LUN(ctsio);
        int retval;
        u_int32_t param_len;
        struct scsi_per_res_out *cdb;
        struct scsi_per_res_out_parms* param;
        uint32_t residx;
        uint64_t res_key, sa_res_key, key;
        uint8_t type;
        union ctl_ha_msg persis_io;
        int    i;

        CTL_DEBUG_PRINT(("ctl_persistent_reserve_out\n"));

        cdb = (struct scsi_per_res_out *)ctsio->cdb;
        retval = CTL_RETVAL_COMPLETE;

        /*
         * We only support whole-LUN scope.  The scope & type are ignored for
         * register, register and ignore existing key and clear.
         * We sometimes ignore scope and type on preempts too!!
         * Verify reservation type here as well.
         */
        type = cdb->scope_type & SPR_TYPE_MASK;
        if ((cdb->action == SPRO_RESERVE)
         || (cdb->action == SPRO_RELEASE)) {
                if ((cdb->scope_type & SPR_SCOPE_MASK) != SPR_LU_SCOPE) {
                        ctl_set_invalid_field(/*ctsio*/ ctsio,
                                              /*sks_valid*/ 1,
                                              /*command*/ 1,
                                              /*field*/ 2,
                                              /*bit_valid*/ 1,
                                              /*bit*/ 4);
                        ctl_done((union ctl_io *)ctsio);
                        return (CTL_RETVAL_COMPLETE);
                }

                if (type>8 || type==2 || type==4 || type==0) {
                        ctl_set_invalid_field(/*ctsio*/ ctsio,
                                              /*sks_valid*/ 1,
                                              /*command*/ 1,
                                              /*field*/ 2,
                                              /*bit_valid*/ 1,
                                              /*bit*/ 0);
                        ctl_done((union ctl_io *)ctsio);
                        return (CTL_RETVAL_COMPLETE);
                }
        }

        param_len = scsi_4btoul(cdb->length);

        if ((ctsio->io_hdr.flags & CTL_FLAG_ALLOCATED) == 0) {
                ctsio->kern_data_ptr = malloc(param_len, M_CTL, M_WAITOK);
                ctsio->kern_data_len = param_len;
                ctsio->kern_total_len = param_len;
                ctsio->kern_rel_offset = 0;
                ctsio->kern_sg_entries = 0;
                ctsio->io_hdr.flags |= CTL_FLAG_ALLOCATED;
                ctsio->be_move_done = ctl_config_move_done;
                ctl_datamove((union ctl_io *)ctsio);

                return (CTL_RETVAL_COMPLETE);
        }

        param = (struct scsi_per_res_out_parms *)ctsio->kern_data_ptr;

        residx = ctl_get_initindex(&ctsio->io_hdr.nexus);
        res_key = scsi_8btou64(param->res_key.key);
        sa_res_key = scsi_8btou64(param->serv_act_res_key);

        /*
         * Validate the reservation key here except for SPRO_REG_IGNO
         * This must be done for all other service actions
         */
        if ((cdb->action & SPRO_ACTION_MASK) != SPRO_REG_IGNO) {
                mtx_lock(&lun->lun_lock);
                if ((key = ctl_get_prkey(lun, residx)) != 0) {
                        if (res_key != key) {
                                /*
                                 * The current key passed in doesn't match
                                 * the one the initiator previously
                                 * registered.
                                 */
                                mtx_unlock(&lun->lun_lock);
                                free(ctsio->kern_data_ptr, M_CTL);
                                ctl_set_reservation_conflict(ctsio);
                                ctl_done((union ctl_io *)ctsio);
                                return (CTL_RETVAL_COMPLETE);
                        }
                } else if ((cdb->action & SPRO_ACTION_MASK) != SPRO_REGISTER) {
                        /*
                         * We are not registered
                         */
                        mtx_unlock(&lun->lun_lock);
                        free(ctsio->kern_data_ptr, M_CTL);
                        ctl_set_reservation_conflict(ctsio);
                        ctl_done((union ctl_io *)ctsio);
                        return (CTL_RETVAL_COMPLETE);
                } else if (res_key != 0) {
                        /*
                         * We are not registered and trying to register but
                         * the register key isn't zero.
                         */
                        mtx_unlock(&lun->lun_lock);
                        free(ctsio->kern_data_ptr, M_CTL);
                        ctl_set_reservation_conflict(ctsio);
                        ctl_done((union ctl_io *)ctsio);
                        return (CTL_RETVAL_COMPLETE);
                }
                mtx_unlock(&lun->lun_lock);
        }

        switch (cdb->action & SPRO_ACTION_MASK) {
        case SPRO_REGISTER:
        case SPRO_REG_IGNO: {

                /*
                 * We don't support any of these options, as we report in
                 * the read capabilities request (see
                 * ctl_persistent_reserve_in(), above).
                 */
                if ((param->flags & SPR_SPEC_I_PT)
                 || (param->flags & SPR_ALL_TG_PT)
                 || (param->flags & SPR_APTPL)) {
                        int bit_ptr;

                        if (param->flags & SPR_APTPL)
                                bit_ptr = 0;
                        else if (param->flags & SPR_ALL_TG_PT)
                                bit_ptr = 2;
                        else /* SPR_SPEC_I_PT */
                                bit_ptr = 3;

                        free(ctsio->kern_data_ptr, M_CTL);
                        ctl_set_invalid_field(ctsio,
                                              /*sks_valid*/ 1,
                                              /*command*/ 0,
                                              /*field*/ 20,
                                              /*bit_valid*/ 1,
                                              /*bit*/ bit_ptr);
                        ctl_done((union ctl_io *)ctsio);
                        return (CTL_RETVAL_COMPLETE);
                }

                mtx_lock(&lun->lun_lock);

                /*
                 * The initiator wants to clear the
                 * key/unregister.
                 */
                if (sa_res_key == 0) {
                        if ((res_key == 0
                          && (cdb->action & SPRO_ACTION_MASK) == SPRO_REGISTER)
                         || ((cdb->action & SPRO_ACTION_MASK) == SPRO_REG_IGNO
                          && ctl_get_prkey(lun, residx) == 0)) {
                                mtx_unlock(&lun->lun_lock);
                                goto done;
                        }

                        ctl_clr_prkey(lun, residx);
                        lun->pr_key_count--;

                        if (residx == lun->pr_res_idx) {
                                lun->flags &= ~CTL_LUN_PR_RESERVED;
                                lun->pr_res_idx = CTL_PR_NO_RESERVATION;

                                if ((lun->pr_res_type == SPR_TYPE_WR_EX_RO ||
                                     lun->pr_res_type == SPR_TYPE_EX_AC_RO) &&
                                    lun->pr_key_count) {
                                        /*
                                         * If the reservation is a registrants
                                         * only type we need to generate a UA
                                         * for other registered inits.  The
                                         * sense code should be RESERVATIONS
                                         * RELEASED
                                         */

                                        for (i = softc->init_min; i < softc->init_max; i++){
                                                if (ctl_get_prkey(lun, i) == 0)
                                                        continue;
                                                ctl_est_ua(lun, i,
                                                    CTL_UA_RES_RELEASE);
                                        }
                                }
                                lun->pr_res_type = 0;
                        } else if (lun->pr_res_idx == CTL_PR_ALL_REGISTRANTS) {
                                if (lun->pr_key_count==0) {
                                        lun->flags &= ~CTL_LUN_PR_RESERVED;
                                        lun->pr_res_type = 0;
                                        lun->pr_res_idx = CTL_PR_NO_RESERVATION;
                                }
                        }
                        lun->pr_generation++;
                        mtx_unlock(&lun->lun_lock);

                        persis_io.hdr.nexus = ctsio->io_hdr.nexus;
                        persis_io.hdr.msg_type = CTL_MSG_PERS_ACTION;
                        persis_io.pr.pr_info.action = CTL_PR_UNREG_KEY;
                        persis_io.pr.pr_info.residx = residx;
                        ctl_ha_msg_send(CTL_HA_CHAN_CTL, &persis_io,
                            sizeof(persis_io.pr), M_WAITOK);
                } else /* sa_res_key != 0 */ {

                        /*
                         * If we aren't registered currently then increment
                         * the key count and set the registered flag.
                         */
                        ctl_alloc_prkey(lun, residx);
                        if (ctl_get_prkey(lun, residx) == 0)
                                lun->pr_key_count++;
                        ctl_set_prkey(lun, residx, sa_res_key);
                        lun->pr_generation++;
                        mtx_unlock(&lun->lun_lock);

                        persis_io.hdr.nexus = ctsio->io_hdr.nexus;
                        persis_io.hdr.msg_type = CTL_MSG_PERS_ACTION;
                        persis_io.pr.pr_info.action = CTL_PR_REG_KEY;
                        persis_io.pr.pr_info.residx = residx;
                        memcpy(persis_io.pr.pr_info.sa_res_key,
                               param->serv_act_res_key,
                               sizeof(param->serv_act_res_key));
                        ctl_ha_msg_send(CTL_HA_CHAN_CTL, &persis_io,
                            sizeof(persis_io.pr), M_WAITOK);
                }

                break;
        }
        case SPRO_RESERVE:
                mtx_lock(&lun->lun_lock);
                if (lun->flags & CTL_LUN_PR_RESERVED) {
                        /*
                         * if this isn't the reservation holder and it's
                         * not a "all registrants" type or if the type is
                         * different then we have a conflict
                         */
                        if ((lun->pr_res_idx != residx
                          && lun->pr_res_idx != CTL_PR_ALL_REGISTRANTS)
                         || lun->pr_res_type != type) {
                                mtx_unlock(&lun->lun_lock);
                                free(ctsio->kern_data_ptr, M_CTL);
                                ctl_set_reservation_conflict(ctsio);
                                ctl_done((union ctl_io *)ctsio);
                                return (CTL_RETVAL_COMPLETE);
                        }
                        mtx_unlock(&lun->lun_lock);
                } else /* create a reservation */ {
                        /*
                         * If it's not an "all registrants" type record
                         * reservation holder
                         */
                        if (type != SPR_TYPE_WR_EX_AR
                         && type != SPR_TYPE_EX_AC_AR)
                                lun->pr_res_idx = residx; /* Res holder */
                        else
                                lun->pr_res_idx = CTL_PR_ALL_REGISTRANTS;

                        lun->flags |= CTL_LUN_PR_RESERVED;
                        lun->pr_res_type = type;

                        mtx_unlock(&lun->lun_lock);

                        /* send msg to other side */
                        persis_io.hdr.nexus = ctsio->io_hdr.nexus;
                        persis_io.hdr.msg_type = CTL_MSG_PERS_ACTION;
                        persis_io.pr.pr_info.action = CTL_PR_RESERVE;
                        persis_io.pr.pr_info.residx = lun->pr_res_idx;
                        persis_io.pr.pr_info.res_type = type;
                        ctl_ha_msg_send(CTL_HA_CHAN_CTL, &persis_io,
                            sizeof(persis_io.pr), M_WAITOK);
                }
                break;

        case SPRO_RELEASE:
                mtx_lock(&lun->lun_lock);
                if ((lun->flags & CTL_LUN_PR_RESERVED) == 0) {
                        /* No reservation exists return good status */
                        mtx_unlock(&lun->lun_lock);
                        goto done;
                }
                /*
                 * Is this nexus a reservation holder?
                 */
                if (lun->pr_res_idx != residx
                 && lun->pr_res_idx != CTL_PR_ALL_REGISTRANTS) {
                        /*
                         * not a res holder return good status but
                         * do nothing
                         */
                        mtx_unlock(&lun->lun_lock);
                        goto done;
                }

                if (lun->pr_res_type != type) {
                        mtx_unlock(&lun->lun_lock);
                        free(ctsio->kern_data_ptr, M_CTL);
                        ctl_set_illegal_pr_release(ctsio);
                        ctl_done((union ctl_io *)ctsio);
                        return (CTL_RETVAL_COMPLETE);
                }

                /* okay to release */
                lun->flags &= ~CTL_LUN_PR_RESERVED;
                lun->pr_res_idx = CTL_PR_NO_RESERVATION;
                lun->pr_res_type = 0;

                /*
                 * If this isn't an exclusive access reservation and NUAR
                 * is not set, generate UA for all other registrants.
                 */
                if (type != SPR_TYPE_EX_AC && type != SPR_TYPE_WR_EX &&
                    (lun->MODE_CTRL.queue_flags & SCP_NUAR) == 0) {
                        for (i = softc->init_min; i < softc->init_max; i++) {
                                if (i == residx || ctl_get_prkey(lun, i) == 0)
                                        continue;
                                ctl_est_ua(lun, i, CTL_UA_RES_RELEASE);
                        }
                }
                mtx_unlock(&lun->lun_lock);

                /* Send msg to other side */
                persis_io.hdr.nexus = ctsio->io_hdr.nexus;
                persis_io.hdr.msg_type = CTL_MSG_PERS_ACTION;
                persis_io.pr.pr_info.action = CTL_PR_RELEASE;
                ctl_ha_msg_send(CTL_HA_CHAN_CTL, &persis_io,
                     sizeof(persis_io.pr), M_WAITOK);
                break;

        case SPRO_CLEAR:
                /* send msg to other side */

                mtx_lock(&lun->lun_lock);
                lun->flags &= ~CTL_LUN_PR_RESERVED;
                lun->pr_res_type = 0;
                lun->pr_key_count = 0;
                lun->pr_res_idx = CTL_PR_NO_RESERVATION;

                ctl_clr_prkey(lun, residx);
                for (i = 0; i < CTL_MAX_INITIATORS; i++)
                        if (ctl_get_prkey(lun, i) != 0) {
                                ctl_clr_prkey(lun, i);
                                ctl_est_ua(lun, i, CTL_UA_REG_PREEMPT);
                        }
                lun->pr_generation++;
                mtx_unlock(&lun->lun_lock);

                persis_io.hdr.nexus = ctsio->io_hdr.nexus;
                persis_io.hdr.msg_type = CTL_MSG_PERS_ACTION;
                persis_io.pr.pr_info.action = CTL_PR_CLEAR;
                ctl_ha_msg_send(CTL_HA_CHAN_CTL, &persis_io,
                     sizeof(persis_io.pr), M_WAITOK);
                break;

        case SPRO_PREEMPT:
        case SPRO_PRE_ABO: {
                int nretval;

                nretval = ctl_pro_preempt(softc, lun, res_key, sa_res_key, type,
                                          residx, ctsio, cdb, param);
                if (nretval != 0)
                        return (CTL_RETVAL_COMPLETE);
                break;
        }
        default:
                panic("%s: Invalid PR type %#x", __func__, cdb->action);
        }

done:
        free(ctsio->kern_data_ptr, M_CTL);
        ctl_set_success(ctsio);
        ctl_done((union ctl_io *)ctsio);

        return (retval);
}

/*
 * This routine is for handling a message from the other SC pertaining to
 * persistent reserve out. All the error checking will have been done
 * so only perorming the action need be done here to keep the two
 * in sync.
 */
static void
ctl_hndl_per_res_out_on_other_sc(union ctl_io *io)
{
        struct ctl_softc *softc = CTL_SOFTC(io);
        union ctl_ha_msg *msg = (union ctl_ha_msg *)&io->presio.pr_msg;
        struct ctl_lun *lun;
        int i;
        uint32_t residx, targ_lun;

        targ_lun = msg->hdr.nexus.targ_mapped_lun;
        mtx_lock(&softc->ctl_lock);
        if (targ_lun >= ctl_max_luns ||
            (lun = softc->ctl_luns[targ_lun]) == NULL) {
                mtx_unlock(&softc->ctl_lock);
                return;
        }
        mtx_lock(&lun->lun_lock);
        mtx_unlock(&softc->ctl_lock);
        if (lun->flags & CTL_LUN_DISABLED) {
                mtx_unlock(&lun->lun_lock);
                return;
        }
        residx = ctl_get_initindex(&msg->hdr.nexus);
        switch(msg->pr.pr_info.action) {
        case CTL_PR_REG_KEY:
                ctl_alloc_prkey(lun, msg->pr.pr_info.residx);
                if (ctl_get_prkey(lun, msg->pr.pr_info.residx) == 0)
                        lun->pr_key_count++;
                ctl_set_prkey(lun, msg->pr.pr_info.residx,
                    scsi_8btou64(msg->pr.pr_info.sa_res_key));
                lun->pr_generation++;
                break;

        case CTL_PR_UNREG_KEY:
                ctl_clr_prkey(lun, msg->pr.pr_info.residx);
                lun->pr_key_count--;

                /* XXX Need to see if the reservation has been released */
                /* if so do we need to generate UA? */
                if (msg->pr.pr_info.residx == lun->pr_res_idx) {
                        lun->flags &= ~CTL_LUN_PR_RESERVED;
                        lun->pr_res_idx = CTL_PR_NO_RESERVATION;

                        if ((lun->pr_res_type == SPR_TYPE_WR_EX_RO ||
                             lun->pr_res_type == SPR_TYPE_EX_AC_RO) &&
                            lun->pr_key_count) {
                                /*
                                 * If the reservation is a registrants
                                 * only type we need to generate a UA
                                 * for other registered inits.  The
                                 * sense code should be RESERVATIONS
                                 * RELEASED
                                 */

                                for (i = softc->init_min; i < softc->init_max; i++) {
                                        if (ctl_get_prkey(lun, i) == 0)
                                                continue;

                                        ctl_est_ua(lun, i, CTL_UA_RES_RELEASE);
                                }
                        }
                        lun->pr_res_type = 0;
                } else if (lun->pr_res_idx == CTL_PR_ALL_REGISTRANTS) {
                        if (lun->pr_key_count==0) {
                                lun->flags &= ~CTL_LUN_PR_RESERVED;
                                lun->pr_res_type = 0;
                                lun->pr_res_idx = CTL_PR_NO_RESERVATION;
                        }
                }
                lun->pr_generation++;
                break;

        case CTL_PR_RESERVE:
                lun->flags |= CTL_LUN_PR_RESERVED;
                lun->pr_res_type = msg->pr.pr_info.res_type;
                lun->pr_res_idx = msg->pr.pr_info.residx;

                break;

        case CTL_PR_RELEASE:
                /*
                 * If this isn't an exclusive access reservation and NUAR
                 * is not set, generate UA for all other registrants.
                 */
                if (lun->pr_res_type != SPR_TYPE_EX_AC &&
                    lun->pr_res_type != SPR_TYPE_WR_EX &&
                    (lun->MODE_CTRL.queue_flags & SCP_NUAR) == 0) {
                        for (i = softc->init_min; i < softc->init_max; i++) {
                                if (i == residx || ctl_get_prkey(lun, i) == 0)
                                        continue;
                                ctl_est_ua(lun, i, CTL_UA_RES_RELEASE);
                        }
                }

                lun->flags &= ~CTL_LUN_PR_RESERVED;
                lun->pr_res_idx = CTL_PR_NO_RESERVATION;
                lun->pr_res_type = 0;
                break;

        case CTL_PR_PREEMPT:
                ctl_pro_preempt_other(lun, msg);
                break;
        case CTL_PR_CLEAR:
                lun->flags &= ~CTL_LUN_PR_RESERVED;
                lun->pr_res_type = 0;
                lun->pr_key_count = 0;
                lun->pr_res_idx = CTL_PR_NO_RESERVATION;

                for (i=0; i < CTL_MAX_INITIATORS; i++) {
                        if (ctl_get_prkey(lun, i) == 0)
                                continue;
                        ctl_clr_prkey(lun, i);
                        ctl_est_ua(lun, i, CTL_UA_REG_PREEMPT);
                }
                lun->pr_generation++;
                break;
        }

        mtx_unlock(&lun->lun_lock);
}

int
ctl_read_write(struct ctl_scsiio *ctsio)
{
        struct ctl_lun *lun = CTL_LUN(ctsio);
        struct ctl_lba_len_flags *lbalen;
        uint64_t lba;
        uint32_t num_blocks;
        int flags, retval;
        int isread;

        CTL_DEBUG_PRINT(("ctl_read_write: command: %#x\n", ctsio->cdb[0]));

        flags = 0;
        isread = ctsio->cdb[0] == READ_6  || ctsio->cdb[0] == READ_10
              || ctsio->cdb[0] == READ_12 || ctsio->cdb[0] == READ_16;
        switch (ctsio->cdb[0]) {
        case READ_6:
        case WRITE_6: {
                struct scsi_rw_6 *cdb;

                cdb = (struct scsi_rw_6 *)ctsio->cdb;

                lba = scsi_3btoul(cdb->addr);
                /* only 5 bits are valid in the most significant address byte */
                lba &= 0x1fffff;
                num_blocks = cdb->length;
                /*
                 * This is correct according to SBC-2.
                 */
                if (num_blocks == 0)
                        num_blocks = 256;
                break;
        }
        case READ_10:
        case WRITE_10: {
                struct scsi_rw_10 *cdb;

                cdb = (struct scsi_rw_10 *)ctsio->cdb;
                if (cdb->byte2 & SRW10_FUA)
                        flags |= CTL_LLF_FUA;
                if (cdb->byte2 & SRW10_DPO)
                        flags |= CTL_LLF_DPO;
                lba = scsi_4btoul(cdb->addr);
                num_blocks = scsi_2btoul(cdb->length);
                break;
        }
        case WRITE_VERIFY_10: {
                struct scsi_write_verify_10 *cdb;

                cdb = (struct scsi_write_verify_10 *)ctsio->cdb;
                flags |= CTL_LLF_FUA;
                if (cdb->byte2 & SWV_DPO)
                        flags |= CTL_LLF_DPO;
                lba = scsi_4btoul(cdb->addr);
                num_blocks = scsi_2btoul(cdb->length);
                break;
        }
        case READ_12:
        case WRITE_12: {
                struct scsi_rw_12 *cdb;

                cdb = (struct scsi_rw_12 *)ctsio->cdb;
                if (cdb->byte2 & SRW12_FUA)
                        flags |= CTL_LLF_FUA;
                if (cdb->byte2 & SRW12_DPO)
                        flags |= CTL_LLF_DPO;
                lba = scsi_4btoul(cdb->addr);
                num_blocks = scsi_4btoul(cdb->length);
                break;
        }
        case WRITE_VERIFY_12: {
                struct scsi_write_verify_12 *cdb;

                cdb = (struct scsi_write_verify_12 *)ctsio->cdb;
                flags |= CTL_LLF_FUA;
                if (cdb->byte2 & SWV_DPO)
                        flags |= CTL_LLF_DPO;
                lba = scsi_4btoul(cdb->addr);
                num_blocks = scsi_4btoul(cdb->length);
                break;
        }
        case READ_16:
        case WRITE_16: {
                struct scsi_rw_16 *cdb;

                cdb = (struct scsi_rw_16 *)ctsio->cdb;
                if (cdb->byte2 & SRW12_FUA)
                        flags |= CTL_LLF_FUA;
                if (cdb->byte2 & SRW12_DPO)
                        flags |= CTL_LLF_DPO;
                lba = scsi_8btou64(cdb->addr);
                num_blocks = scsi_4btoul(cdb->length);
                break;
        }
        case WRITE_ATOMIC_16: {
                struct scsi_write_atomic_16 *cdb;

                if (lun->be_lun->atomicblock == 0) {
                        ctl_set_invalid_opcode(ctsio);
                        ctl_done((union ctl_io *)ctsio);
                        return (CTL_RETVAL_COMPLETE);
                }

                cdb = (struct scsi_write_atomic_16 *)ctsio->cdb;
                if (cdb->byte2 & SRW12_FUA)
                        flags |= CTL_LLF_FUA;
                if (cdb->byte2 & SRW12_DPO)
                        flags |= CTL_LLF_DPO;
                lba = scsi_8btou64(cdb->addr);
                num_blocks = scsi_2btoul(cdb->length);
                if (num_blocks > lun->be_lun->atomicblock) {
                        ctl_set_invalid_field(ctsio, /*sks_valid*/ 1,
                            /*command*/ 1, /*field*/ 12, /*bit_valid*/ 0,
                            /*bit*/ 0);
                        ctl_done((union ctl_io *)ctsio);
                        return (CTL_RETVAL_COMPLETE);
                }
                break;
        }
        case WRITE_VERIFY_16: {
                struct scsi_write_verify_16 *cdb;

                cdb = (struct scsi_write_verify_16 *)ctsio->cdb;
                flags |= CTL_LLF_FUA;
                if (cdb->byte2 & SWV_DPO)
                        flags |= CTL_LLF_DPO;
                lba = scsi_8btou64(cdb->addr);
                num_blocks = scsi_4btoul(cdb->length);
                break;
        }
        default:
                /*
                 * We got a command we don't support.  This shouldn't
                 * happen, commands should be filtered out above us.
                 */
                ctl_set_invalid_opcode(ctsio);
                ctl_done((union ctl_io *)ctsio);

                return (CTL_RETVAL_COMPLETE);
                break; /* NOTREACHED */
        }

        /*
         * The first check is to make sure we're in bounds, the second
         * check is to catch wrap-around problems.  If the lba + num blocks
         * is less than the lba, then we've wrapped around and the block
         * range is invalid anyway.
         */
        if (((lba + num_blocks) > (lun->be_lun->maxlba + 1))
         || ((lba + num_blocks) < lba)) {
                ctl_set_lba_out_of_range(ctsio,
                    MAX(lba, lun->be_lun->maxlba + 1));
                ctl_done((union ctl_io *)ctsio);
                return (CTL_RETVAL_COMPLETE);
        }

        /*
         * According to SBC-3, a transfer length of 0 is not an error.
         * Note that this cannot happen with WRITE(6) or READ(6), since 0
         * translates to 256 blocks for those commands.
         */
        if (num_blocks == 0) {
                ctl_set_success(ctsio);
                ctl_done((union ctl_io *)ctsio);
                return (CTL_RETVAL_COMPLETE);
        }

        /* Set FUA and/or DPO if caches are disabled. */
        if (isread) {
                if ((lun->MODE_CACHING.flags1 & SCP_RCD) != 0)
                        flags |= CTL_LLF_FUA | CTL_LLF_DPO;
        } else {
                if ((lun->MODE_CACHING.flags1 & SCP_WCE) == 0)
                        flags |= CTL_LLF_FUA;
        }

        lbalen = (struct ctl_lba_len_flags *)
            &ctsio->io_hdr.ctl_private[CTL_PRIV_LBA_LEN];
        lbalen->lba = lba;
        lbalen->len = num_blocks;
        lbalen->flags = (isread ? CTL_LLF_READ : CTL_LLF_WRITE) | flags;

        ctsio->kern_total_len = num_blocks * lun->be_lun->blocksize;
        ctsio->kern_rel_offset = 0;

        CTL_DEBUG_PRINT(("ctl_read_write: calling data_submit()\n"));

        retval = lun->backend->data_submit((union ctl_io *)ctsio);
        return (retval);
}

static int
ctl_cnw_cont(union ctl_io *io)
{
        struct ctl_lun *lun = CTL_LUN(io);
        struct ctl_scsiio *ctsio;
        struct ctl_lba_len_flags *lbalen;
        int retval;

        ctsio = &io->scsiio;
        ctsio->io_hdr.status = CTL_STATUS_NONE;
        ctsio->io_hdr.flags &= ~CTL_FLAG_IO_CONT;
        lbalen = (struct ctl_lba_len_flags *)
            &ctsio->io_hdr.ctl_private[CTL_PRIV_LBA_LEN];
        lbalen->flags &= ~CTL_LLF_COMPARE;
        lbalen->flags |= CTL_LLF_WRITE;

        CTL_DEBUG_PRINT(("ctl_cnw_cont: calling data_submit()\n"));
        retval = lun->backend->data_submit((union ctl_io *)ctsio);
        return (retval);
}

int
ctl_cnw(struct ctl_scsiio *ctsio)
{
        struct ctl_lun *lun = CTL_LUN(ctsio);
        struct ctl_lba_len_flags *lbalen;
        uint64_t lba;
        uint32_t num_blocks;
        int flags, retval;

        CTL_DEBUG_PRINT(("ctl_cnw: command: %#x\n", ctsio->cdb[0]));

        flags = 0;
        switch (ctsio->cdb[0]) {
        case COMPARE_AND_WRITE: {
                struct scsi_compare_and_write *cdb;

                cdb = (struct scsi_compare_and_write *)ctsio->cdb;
                if (cdb->byte2 & SRW10_FUA)
                        flags |= CTL_LLF_FUA;
                if (cdb->byte2 & SRW10_DPO)
                        flags |= CTL_LLF_DPO;
                lba = scsi_8btou64(cdb->addr);
                num_blocks = cdb->length;
                break;
        }
        default:
                /*
                 * We got a command we don't support.  This shouldn't
                 * happen, commands should be filtered out above us.
                 */
                ctl_set_invalid_opcode(ctsio);
                ctl_done((union ctl_io *)ctsio);

                return (CTL_RETVAL_COMPLETE);
                break; /* NOTREACHED */
        }

        /*
         * The first check is to make sure we're in bounds, the second
         * check is to catch wrap-around problems.  If the lba + num blocks
         * is less than the lba, then we've wrapped around and the block
         * range is invalid anyway.
         */
        if (((lba + num_blocks) > (lun->be_lun->maxlba + 1))
         || ((lba + num_blocks) < lba)) {
                ctl_set_lba_out_of_range(ctsio,
                    MAX(lba, lun->be_lun->maxlba + 1));
                ctl_done((union ctl_io *)ctsio);
                return (CTL_RETVAL_COMPLETE);
        }

        /*
         * According to SBC-3, a transfer length of 0 is not an error.
         */
        if (num_blocks == 0) {
                ctl_set_success(ctsio);
                ctl_done((union ctl_io *)ctsio);
                return (CTL_RETVAL_COMPLETE);
        }

        /* Set FUA if write cache is disabled. */
        if ((lun->MODE_CACHING.flags1 & SCP_WCE) == 0)
                flags |= CTL_LLF_FUA;

        ctsio->kern_total_len = 2 * num_blocks * lun->be_lun->blocksize;
        ctsio->kern_rel_offset = 0;

        /*
         * Set the IO_CONT flag, so that if this I/O gets passed to
         * ctl_data_submit_done(), it'll get passed back to
         * ctl_ctl_cnw_cont() for further processing.
         */
        ctsio->io_hdr.flags |= CTL_FLAG_IO_CONT;
        ctsio->io_cont = ctl_cnw_cont;

        lbalen = (struct ctl_lba_len_flags *)
            &ctsio->io_hdr.ctl_private[CTL_PRIV_LBA_LEN];
        lbalen->lba = lba;
        lbalen->len = num_blocks;
        lbalen->flags = CTL_LLF_COMPARE | flags;

        CTL_DEBUG_PRINT(("ctl_cnw: calling data_submit()\n"));
        retval = lun->backend->data_submit((union ctl_io *)ctsio);
        return (retval);
}

int
ctl_verify(struct ctl_scsiio *ctsio)
{
        struct ctl_lun *lun = CTL_LUN(ctsio);
        struct ctl_lba_len_flags *lbalen;
        uint64_t lba;
        uint32_t num_blocks;
        int bytchk, flags;
        int retval;

        CTL_DEBUG_PRINT(("ctl_verify: command: %#x\n", ctsio->cdb[0]));

        bytchk = 0;
        flags = CTL_LLF_FUA;
        switch (ctsio->cdb[0]) {
        case VERIFY_10: {
                struct scsi_verify_10 *cdb;

                cdb = (struct scsi_verify_10 *)ctsio->cdb;
                if (cdb->byte2 & SVFY_BYTCHK)
                        bytchk = 1;
                if (cdb->byte2 & SVFY_DPO)
                        flags |= CTL_LLF_DPO;
                lba = scsi_4btoul(cdb->addr);
                num_blocks = scsi_2btoul(cdb->length);
                break;
        }
        case VERIFY_12: {
                struct scsi_verify_12 *cdb;

                cdb = (struct scsi_verify_12 *)ctsio->cdb;
                if (cdb->byte2 & SVFY_BYTCHK)
                        bytchk = 1;
                if (cdb->byte2 & SVFY_DPO)
                        flags |= CTL_LLF_DPO;
                lba = scsi_4btoul(cdb->addr);
                num_blocks = scsi_4btoul(cdb->length);
                break;
        }
        case VERIFY_16: {
                struct scsi_rw_16 *cdb;

                cdb = (struct scsi_rw_16 *)ctsio->cdb;
                if (cdb->byte2 & SVFY_BYTCHK)
                        bytchk = 1;
                if (cdb->byte2 & SVFY_DPO)
                        flags |= CTL_LLF_DPO;
                lba = scsi_8btou64(cdb->addr);
                num_blocks = scsi_4btoul(cdb->length);
                break;
        }
        default:
                /*
                 * We got a command we don't support.  This shouldn't
                 * happen, commands should be filtered out above us.
                 */
                ctl_set_invalid_opcode(ctsio);
                ctl_done((union ctl_io *)ctsio);
                return (CTL_RETVAL_COMPLETE);
        }

        /*
         * The first check is to make sure we're in bounds, the second
         * check is to catch wrap-around problems.  If the lba + num blocks
         * is less than the lba, then we've wrapped around and the block
         * range is invalid anyway.
         */
        if (((lba + num_blocks) > (lun->be_lun->maxlba + 1))
         || ((lba + num_blocks) < lba)) {
                ctl_set_lba_out_of_range(ctsio,
                    MAX(lba, lun->be_lun->maxlba + 1));
                ctl_done((union ctl_io *)ctsio);
                return (CTL_RETVAL_COMPLETE);
        }

        /*
         * According to SBC-3, a transfer length of 0 is not an error.
         */
        if (num_blocks == 0) {
                ctl_set_success(ctsio);
                ctl_done((union ctl_io *)ctsio);
                return (CTL_RETVAL_COMPLETE);
        }

        lbalen = (struct ctl_lba_len_flags *)
            &ctsio->io_hdr.ctl_private[CTL_PRIV_LBA_LEN];
        lbalen->lba = lba;
        lbalen->len = num_blocks;
        if (bytchk) {
                lbalen->flags = CTL_LLF_COMPARE | flags;
                ctsio->kern_total_len = num_blocks * lun->be_lun->blocksize;
        } else {
                lbalen->flags = CTL_LLF_VERIFY | flags;
                ctsio->kern_total_len = 0;
        }
        ctsio->kern_rel_offset = 0;

        CTL_DEBUG_PRINT(("ctl_verify: calling data_submit()\n"));
        retval = lun->backend->data_submit((union ctl_io *)ctsio);
        return (retval);
}

int
ctl_report_luns(struct ctl_scsiio *ctsio)
{
        struct ctl_softc *softc = CTL_SOFTC(ctsio);
        struct ctl_port *port = CTL_PORT(ctsio);
        struct ctl_lun *lun, *request_lun = CTL_LUN(ctsio);
        struct scsi_report_luns *cdb;
        struct scsi_report_luns_data *lun_data;
        int num_filled, num_luns, num_port_luns, retval;
        uint32_t alloc_len, lun_datalen;
        uint32_t initidx, targ_lun_id, lun_id;

        retval = CTL_RETVAL_COMPLETE;
        cdb = (struct scsi_report_luns *)ctsio->cdb;

        CTL_DEBUG_PRINT(("ctl_report_luns\n"));

        num_luns = 0;
        num_port_luns = port->lun_map ? port->lun_map_size : ctl_max_luns;
        mtx_lock(&softc->ctl_lock);
        for (targ_lun_id = 0; targ_lun_id < num_port_luns; targ_lun_id++) {
                if (ctl_lun_map_from_port(port, targ_lun_id) != UINT32_MAX)
                        num_luns++;
        }
        mtx_unlock(&softc->ctl_lock);

        switch (cdb->select_report) {
        case RPL_REPORT_DEFAULT:
        case RPL_REPORT_ALL:
        case RPL_REPORT_NONSUBSID:
                break;
        case RPL_REPORT_WELLKNOWN:
        case RPL_REPORT_ADMIN:
        case RPL_REPORT_CONGLOM:
                num_luns = 0;
                break;
        default:
                ctl_set_invalid_field(ctsio,
                                      /*sks_valid*/ 1,
                                      /*command*/ 1,
                                      /*field*/ 2,
                                      /*bit_valid*/ 0,
                                      /*bit*/ 0);
                ctl_done((union ctl_io *)ctsio);
                return (retval);
                break; /* NOTREACHED */
        }

        alloc_len = scsi_4btoul(cdb->length);
        /*
         * The initiator has to allocate at least 16 bytes for this request,
         * so he can at least get the header and the first LUN.  Otherwise
         * we reject the request (per SPC-3 rev 14, section 6.21).
         */
        if (alloc_len < (sizeof(struct scsi_report_luns_data) +
            sizeof(struct scsi_report_luns_lundata))) {
                ctl_set_invalid_field(ctsio,
                                      /*sks_valid*/ 1,
                                      /*command*/ 1,
                                      /*field*/ 6,
                                      /*bit_valid*/ 0,
                                      /*bit*/ 0);
                ctl_done((union ctl_io *)ctsio);
                return (retval);
        }

        lun_datalen = sizeof(*lun_data) +
                (num_luns * sizeof(struct scsi_report_luns_lundata));

        ctsio->kern_data_ptr = malloc(lun_datalen, M_CTL, M_WAITOK | M_ZERO);
        lun_data = (struct scsi_report_luns_data *)ctsio->kern_data_ptr;
        ctsio->kern_sg_entries = 0;

        initidx = ctl_get_initindex(&ctsio->io_hdr.nexus);

        mtx_lock(&softc->ctl_lock);
        for (targ_lun_id = 0, num_filled = 0;
            targ_lun_id < num_port_luns && num_filled < num_luns;
            targ_lun_id++) {
                lun_id = ctl_lun_map_from_port(port, targ_lun_id);
                if (lun_id == UINT32_MAX)
                        continue;
                lun = softc->ctl_luns[lun_id];
                if (lun == NULL)
                        continue;

                be64enc(lun_data->luns[num_filled++].lundata,
                    ctl_encode_lun(targ_lun_id));

                /*
                 * According to SPC-3, rev 14 section 6.21:
                 *
                 * "The execution of a REPORT LUNS command to any valid and
                 * installed logical unit shall clear the REPORTED LUNS DATA
                 * HAS CHANGED unit attention condition for all logical
                 * units of that target with respect to the requesting
                 * initiator. A valid and installed logical unit is one
                 * having a PERIPHERAL QUALIFIER of 000b in the standard
                 * INQUIRY data (see 6.4.2)."
                 *
                 * If request_lun is NULL, the LUN this report luns command
                 * was issued to is either disabled or doesn't exist. In that
                 * case, we shouldn't clear any pending lun change unit
                 * attention.
                 */
                if (request_lun != NULL) {
                        mtx_lock(&lun->lun_lock);
                        ctl_clr_ua(lun, initidx, CTL_UA_LUN_CHANGE);
                        mtx_unlock(&lun->lun_lock);
                }
        }
        mtx_unlock(&softc->ctl_lock);

        /*
         * It's quite possible that we've returned fewer LUNs than we allocated
         * space for.  Trim it.
         */
        lun_datalen = sizeof(*lun_data) +
                (num_filled * sizeof(struct scsi_report_luns_lundata));
        ctsio->kern_rel_offset = 0;
        ctsio->kern_sg_entries = 0;
        ctsio->kern_data_len = min(lun_datalen, alloc_len);
        ctsio->kern_total_len = ctsio->kern_data_len;

        /*
         * We set this to the actual data length, regardless of how much
         * space we actually have to return results.  If the user looks at
         * this value, he'll know whether or not he allocated enough space
         * and reissue the command if necessary.  We don't support well
         * known logical units, so if the user asks for that, return none.
         */
        scsi_ulto4b(lun_datalen - 8, lun_data->length);

        /*
         * We can only return SCSI_STATUS_CHECK_COND when we can't satisfy
         * this request.
         */
        ctl_set_success(ctsio);
        ctsio->io_hdr.flags |= CTL_FLAG_ALLOCATED;
        ctsio->be_move_done = ctl_config_move_done;
        ctl_datamove((union ctl_io *)ctsio);
        return (retval);
}

int
ctl_request_sense(struct ctl_scsiio *ctsio)
{
        struct ctl_softc *softc = CTL_SOFTC(ctsio);
        struct ctl_lun *lun = CTL_LUN(ctsio);
        struct scsi_request_sense *cdb;
        struct scsi_sense_data *sense_ptr, *ps;
        uint32_t initidx;
        int have_error;
        u_int sense_len = SSD_FULL_SIZE;
        scsi_sense_data_type sense_format;
        ctl_ua_type ua_type;
        uint8_t asc = 0, ascq = 0;

        cdb = (struct scsi_request_sense *)ctsio->cdb;

        CTL_DEBUG_PRINT(("ctl_request_sense\n"));

        /*
         * Determine which sense format the user wants.
         */
        if (cdb->byte2 & SRS_DESC)
                sense_format = SSD_TYPE_DESC;
        else
                sense_format = SSD_TYPE_FIXED;

        ctsio->kern_data_ptr = malloc(sizeof(*sense_ptr), M_CTL, M_WAITOK);
        sense_ptr = (struct scsi_sense_data *)ctsio->kern_data_ptr;
        ctsio->kern_sg_entries = 0;
        ctsio->kern_rel_offset = 0;

        /*
         * struct scsi_sense_data, which is currently set to 256 bytes, is
         * larger than the largest allowed value for the length field in the
         * REQUEST SENSE CDB, which is 252 bytes as of SPC-4.
         */
        ctsio->kern_data_len = cdb->length;
        ctsio->kern_total_len = cdb->length;

        /*
         * If we don't have a LUN, we don't have any pending sense.
         */
        if (lun == NULL ||
            ((lun->flags & CTL_LUN_PRIMARY_SC) == 0 &&
             softc->ha_link < CTL_HA_LINK_UNKNOWN)) {
                /* "Logical unit not supported" */
                ctl_set_sense_data(sense_ptr, &sense_len, NULL, sense_format,
                    /*current_error*/ 1,
                    /*sense_key*/ SSD_KEY_ILLEGAL_REQUEST,
                    /*asc*/ 0x25,
                    /*ascq*/ 0x00,
                    SSD_ELEM_NONE);
                goto send;
        }

        have_error = 0;
        initidx = ctl_get_initindex(&ctsio->io_hdr.nexus);
        /*
         * Check for pending sense, and then for pending unit attentions.
         * Pending sense gets returned first, then pending unit attentions.
         */
        mtx_lock(&lun->lun_lock);
        ps = lun->pending_sense[initidx / CTL_MAX_INIT_PER_PORT];
        if (ps != NULL)
                ps += initidx % CTL_MAX_INIT_PER_PORT;
        if (ps != NULL && ps->error_code != 0) {
                scsi_sense_data_type stored_format;

                /*
                 * Check to see which sense format was used for the stored
                 * sense data.
                 */
                stored_format = scsi_sense_type(ps);

                /*
                 * If the user requested a different sense format than the
                 * one we stored, then we need to convert it to the other
                 * format.  If we're going from descriptor to fixed format
                 * sense data, we may lose things in translation, depending
                 * on what options were used.
                 *
                 * If the stored format is SSD_TYPE_NONE (i.e. invalid),
                 * for some reason we'll just copy it out as-is.
                 */
                if ((stored_format == SSD_TYPE_FIXED)
                 && (sense_format == SSD_TYPE_DESC))
                        ctl_sense_to_desc((struct scsi_sense_data_fixed *)
                            ps, (struct scsi_sense_data_desc *)sense_ptr);
                else if ((stored_format == SSD_TYPE_DESC)
                      && (sense_format == SSD_TYPE_FIXED))
                        ctl_sense_to_fixed((struct scsi_sense_data_desc *)
                            ps, (struct scsi_sense_data_fixed *)sense_ptr);
                else
                        memcpy(sense_ptr, ps, sizeof(*sense_ptr));

                ps->error_code = 0;
                have_error = 1;
        } else {
                ua_type = ctl_build_ua(lun, initidx, sense_ptr, &sense_len,
                    sense_format);
                if (ua_type != CTL_UA_NONE)
                        have_error = 1;
        }
        if (have_error == 0) {
                /*
                 * Report informational exception if have one and allowed.
                 */
                if (lun->MODE_IE.mrie != SIEP_MRIE_NO) {
                        asc = lun->ie_asc;
                        ascq = lun->ie_ascq;
                }
                ctl_set_sense_data(sense_ptr, &sense_len, lun, sense_format,
                    /*current_error*/ 1,
                    /*sense_key*/ SSD_KEY_NO_SENSE,
                    /*asc*/ asc,
                    /*ascq*/ ascq,
                    SSD_ELEM_NONE);
        }
        mtx_unlock(&lun->lun_lock);

send:
        /*
         * We report the SCSI status as OK, since the status of the command
         * itself is OK.  We're reporting sense as parameter data.
         */
        ctl_set_success(ctsio);
        ctsio->io_hdr.flags |= CTL_FLAG_ALLOCATED;
        ctsio->be_move_done = ctl_config_move_done;
        ctl_datamove((union ctl_io *)ctsio);
        return (CTL_RETVAL_COMPLETE);
}

int
ctl_tur(struct ctl_scsiio *ctsio)
{

        CTL_DEBUG_PRINT(("ctl_tur\n"));

        ctl_set_success(ctsio);
        ctl_done((union ctl_io *)ctsio);

        return (CTL_RETVAL_COMPLETE);
}

/*
 * SCSI VPD page 0x00, the Supported VPD Pages page.
 */
static int
ctl_inquiry_evpd_supported(struct ctl_scsiio *ctsio, int alloc_len)
{
        struct ctl_lun *lun = CTL_LUN(ctsio);
        struct scsi_vpd_supported_pages *pages;
        int sup_page_size;
        int p;

        sup_page_size = sizeof(struct scsi_vpd_supported_pages) *
            SCSI_EVPD_NUM_SUPPORTED_PAGES;
        ctsio->kern_data_ptr = malloc(sup_page_size, M_CTL, M_WAITOK | M_ZERO);
        pages = (struct scsi_vpd_supported_pages *)ctsio->kern_data_ptr;
        ctsio->kern_rel_offset = 0;
        ctsio->kern_sg_entries = 0;
        ctsio->kern_data_len = min(sup_page_size, alloc_len);
        ctsio->kern_total_len = ctsio->kern_data_len;

        /*
         * The control device is always connected.  The disk device, on the
         * other hand, may not be online all the time.  Need to change this
         * to figure out whether the disk device is actually online or not.
         */
        if (lun != NULL)
                pages->device = (SID_QUAL_LU_CONNECTED << 5) |
                                lun->be_lun->lun_type;
        else
                pages->device = (SID_QUAL_LU_OFFLINE << 5) | T_DIRECT;

        p = 0;
        /* Supported VPD pages */
        pages->page_list[p++] = SVPD_SUPPORTED_PAGES;
        /* Serial Number */
        pages->page_list[p++] = SVPD_UNIT_SERIAL_NUMBER;
        /* Device Identification */
        pages->page_list[p++] = SVPD_DEVICE_ID;
        /* Extended INQUIRY Data */
        pages->page_list[p++] = SVPD_EXTENDED_INQUIRY_DATA;
        /* Mode Page Policy */
        pages->page_list[p++] = SVPD_MODE_PAGE_POLICY;
        /* SCSI Ports */
        pages->page_list[p++] = SVPD_SCSI_PORTS;
        /* Third-party Copy */
        pages->page_list[p++] = SVPD_SCSI_TPC;
        /* SCSI Feature Sets */
        pages->page_list[p++] = SVPD_SCSI_SFS;
        if (lun != NULL && lun->be_lun->lun_type == T_DIRECT) {
                /* Block limits */
                pages->page_list[p++] = SVPD_BLOCK_LIMITS;
                /* Block Device Characteristics */
                pages->page_list[p++] = SVPD_BDC;
                /* Logical Block Provisioning */
                pages->page_list[p++] = SVPD_LBP;
        }
        pages->length = p;

        ctl_set_success(ctsio);
        ctsio->io_hdr.flags |= CTL_FLAG_ALLOCATED;
        ctsio->be_move_done = ctl_config_move_done;
        ctl_datamove((union ctl_io *)ctsio);
        return (CTL_RETVAL_COMPLETE);
}

/*
 * SCSI VPD page 0x80, the Unit Serial Number page.
 */
static int
ctl_inquiry_evpd_serial(struct ctl_scsiio *ctsio, int alloc_len)
{
        struct ctl_lun *lun = CTL_LUN(ctsio);
        struct scsi_vpd_unit_serial_number *sn_ptr;
        int data_len;

        data_len = 4 + CTL_SN_LEN;
        ctsio->kern_data_ptr = malloc(data_len, M_CTL, M_WAITOK | M_ZERO);
        sn_ptr = (struct scsi_vpd_unit_serial_number *)ctsio->kern_data_ptr;
        ctsio->kern_rel_offset = 0;
        ctsio->kern_sg_entries = 0;
        ctsio->kern_data_len = min(data_len, alloc_len);
        ctsio->kern_total_len = ctsio->kern_data_len;

        /*
         * The control device is always connected.  The disk device, on the
         * other hand, may not be online all the time.  Need to change this
         * to figure out whether the disk device is actually online or not.
         */
        if (lun != NULL)
                sn_ptr->device = (SID_QUAL_LU_CONNECTED << 5) |
                                  lun->be_lun->lun_type;
        else
                sn_ptr->device = (SID_QUAL_LU_OFFLINE << 5) | T_DIRECT;

        sn_ptr->page_code = SVPD_UNIT_SERIAL_NUMBER;
        sn_ptr->length = CTL_SN_LEN;
        /*
         * If we don't have a LUN, we just leave the serial number as
         * all spaces.
         */
        if (lun != NULL) {
                strncpy((char *)sn_ptr->serial_num,
                        (char *)lun->be_lun->serial_num, CTL_SN_LEN);
        } else
                memset(sn_ptr->serial_num, 0x20, CTL_SN_LEN);

        ctl_set_success(ctsio);
        ctsio->io_hdr.flags |= CTL_FLAG_ALLOCATED;
        ctsio->be_move_done = ctl_config_move_done;
        ctl_datamove((union ctl_io *)ctsio);
        return (CTL_RETVAL_COMPLETE);
}


/*
 * SCSI VPD page 0x86, the Extended INQUIRY Data page.
 */
static int
ctl_inquiry_evpd_eid(struct ctl_scsiio *ctsio, int alloc_len)
{
        struct ctl_lun *lun = CTL_LUN(ctsio);
        struct scsi_vpd_extended_inquiry_data *eid_ptr;
        int data_len;

        data_len = sizeof(struct scsi_vpd_extended_inquiry_data);
        ctsio->kern_data_ptr = malloc(data_len, M_CTL, M_WAITOK | M_ZERO);
        eid_ptr = (struct scsi_vpd_extended_inquiry_data *)ctsio->kern_data_ptr;
        ctsio->kern_sg_entries = 0;
        ctsio->kern_rel_offset = 0;
        ctsio->kern_data_len = min(data_len, alloc_len);
        ctsio->kern_total_len = ctsio->kern_data_len;

        /*
         * The control device is always connected.  The disk device, on the
         * other hand, may not be online all the time.
         */
        if (lun != NULL)
                eid_ptr->device = (SID_QUAL_LU_CONNECTED << 5) |
                                     lun->be_lun->lun_type;
        else
                eid_ptr->device = (SID_QUAL_LU_OFFLINE << 5) | T_DIRECT;
        eid_ptr->page_code = SVPD_EXTENDED_INQUIRY_DATA;
        scsi_ulto2b(data_len - 4, eid_ptr->page_length);
        /*
         * We support head of queue, ordered and simple tags.
         */
        eid_ptr->flags2 = SVPD_EID_HEADSUP | SVPD_EID_ORDSUP | SVPD_EID_SIMPSUP;
        /*
         * Volatile cache supported.
         */
        eid_ptr->flags3 = SVPD_EID_V_SUP;

        /*
         * This means that we clear the REPORTED LUNS DATA HAS CHANGED unit
         * attention for a particular IT nexus on all LUNs once we report
         * it to that nexus once.  This bit is required as of SPC-4.
         */
        eid_ptr->flags4 = SVPD_EID_LUICLR;

        /*
         * We support revert to defaults (RTD) bit in MODE SELECT.
         */
        eid_ptr->flags5 = SVPD_EID_RTD_SUP;

        /*
         * XXX KDM in order to correctly answer this, we would need
         * information from the SIM to determine how much sense data it
         * can send.  So this would really be a path inquiry field, most
         * likely.  This can be set to a maximum of 252 according to SPC-4,
         * but the hardware may or may not be able to support that much.
         * 0 just means that the maximum sense data length is not reported.
         */
        eid_ptr->max_sense_length = 0;

        ctl_set_success(ctsio);
        ctsio->io_hdr.flags |= CTL_FLAG_ALLOCATED;
        ctsio->be_move_done = ctl_config_move_done;
        ctl_datamove((union ctl_io *)ctsio);
        return (CTL_RETVAL_COMPLETE);
}

static int
ctl_inquiry_evpd_mpp(struct ctl_scsiio *ctsio, int alloc_len)
{
        struct ctl_lun *lun = CTL_LUN(ctsio);
        struct scsi_vpd_mode_page_policy *mpp_ptr;
        int data_len;

        data_len = sizeof(struct scsi_vpd_mode_page_policy) +
            sizeof(struct scsi_vpd_mode_page_policy_descr);

        ctsio->kern_data_ptr = malloc(data_len, M_CTL, M_WAITOK | M_ZERO);
        mpp_ptr = (struct scsi_vpd_mode_page_policy *)ctsio->kern_data_ptr;
        ctsio->kern_rel_offset = 0;
        ctsio->kern_sg_entries = 0;
        ctsio->kern_data_len = min(data_len, alloc_len);
        ctsio->kern_total_len = ctsio->kern_data_len;

        /*
         * The control device is always connected.  The disk device, on the
         * other hand, may not be online all the time.
         */
        if (lun != NULL)
                mpp_ptr->device = (SID_QUAL_LU_CONNECTED << 5) |
                                     lun->be_lun->lun_type;
        else
                mpp_ptr->device = (SID_QUAL_LU_OFFLINE << 5) | T_DIRECT;
        mpp_ptr->page_code = SVPD_MODE_PAGE_POLICY;
        scsi_ulto2b(data_len - 4, mpp_ptr->page_length);
        mpp_ptr->descr[0].page_code = 0x3f;
        mpp_ptr->descr[0].subpage_code = 0xff;
        mpp_ptr->descr[0].policy = SVPD_MPP_SHARED;

        ctl_set_success(ctsio);
        ctsio->io_hdr.flags |= CTL_FLAG_ALLOCATED;
        ctsio->be_move_done = ctl_config_move_done;
        ctl_datamove((union ctl_io *)ctsio);
        return (CTL_RETVAL_COMPLETE);
}

/*
 * SCSI VPD page 0x83, the Device Identification page.
 */
static int
ctl_inquiry_evpd_devid(struct ctl_scsiio *ctsio, int alloc_len)
{
        struct ctl_softc *softc = CTL_SOFTC(ctsio);
        struct ctl_port *port = CTL_PORT(ctsio);
        struct ctl_lun *lun = CTL_LUN(ctsio);
        struct scsi_vpd_device_id *devid_ptr;
        struct scsi_vpd_id_descriptor *desc;
        int data_len, g;
        uint8_t proto;

        data_len = sizeof(struct scsi_vpd_device_id) +
            sizeof(struct scsi_vpd_id_descriptor) +
                sizeof(struct scsi_vpd_id_rel_trgt_port_id) +
            sizeof(struct scsi_vpd_id_descriptor) +
                sizeof(struct scsi_vpd_id_trgt_port_grp_id);
        if (lun && lun->lun_devid)
                data_len += lun->lun_devid->len;
        if (port && port->port_devid)
                data_len += port->port_devid->len;
        if (port && port->target_devid)
                data_len += port->target_devid->len;

        ctsio->kern_data_ptr = malloc(data_len, M_CTL, M_WAITOK | M_ZERO);
        devid_ptr = (struct scsi_vpd_device_id *)ctsio->kern_data_ptr;
        ctsio->kern_sg_entries = 0;
        ctsio->kern_rel_offset = 0;
        ctsio->kern_sg_entries = 0;
        ctsio->kern_data_len = min(data_len, alloc_len);
        ctsio->kern_total_len = ctsio->kern_data_len;

        /*
         * The control device is always connected.  The disk device, on the
         * other hand, may not be online all the time.
         */
        if (lun != NULL)
                devid_ptr->device = (SID_QUAL_LU_CONNECTED << 5) |
                                     lun->be_lun->lun_type;
        else
                devid_ptr->device = (SID_QUAL_LU_OFFLINE << 5) | T_DIRECT;
        devid_ptr->page_code = SVPD_DEVICE_ID;
        scsi_ulto2b(data_len - 4, devid_ptr->length);

        if (port && port->port_type == CTL_PORT_FC)
                proto = SCSI_PROTO_FC << 4;
        else if (port && port->port_type == CTL_PORT_SAS)
                proto = SCSI_PROTO_SAS << 4;
        else if (port && port->port_type == CTL_PORT_ISCSI)
                proto = SCSI_PROTO_ISCSI << 4;
        else
                proto = SCSI_PROTO_SPI << 4;
        desc = (struct scsi_vpd_id_descriptor *)devid_ptr->desc_list;

        /*
         * We're using a LUN association here.  i.e., this device ID is a
         * per-LUN identifier.
         */
        if (lun && lun->lun_devid) {
                memcpy(desc, lun->lun_devid->data, lun->lun_devid->len);
                desc = (struct scsi_vpd_id_descriptor *)((uint8_t *)desc +
                    lun->lun_devid->len);
        }

        /*
         * This is for the WWPN which is a port association.
         */
        if (port && port->port_devid) {
                memcpy(desc, port->port_devid->data, port->port_devid->len);
                desc = (struct scsi_vpd_id_descriptor *)((uint8_t *)desc +
                    port->port_devid->len);
        }

        /*
         * This is for the Relative Target Port(type 4h) identifier
         */
        desc->proto_codeset = proto | SVPD_ID_CODESET_BINARY;
        desc->id_type = SVPD_ID_PIV | SVPD_ID_ASSOC_PORT |
            SVPD_ID_TYPE_RELTARG;
        desc->length = 4;
        scsi_ulto2b(ctsio->io_hdr.nexus.targ_port, &desc->identifier[2]);
        desc = (struct scsi_vpd_id_descriptor *)(&desc->identifier[0] +
            sizeof(struct scsi_vpd_id_rel_trgt_port_id));

        /*
         * This is for the Target Port Group(type 5h) identifier
         */
        desc->proto_codeset = proto | SVPD_ID_CODESET_BINARY;
        desc->id_type = SVPD_ID_PIV | SVPD_ID_ASSOC_PORT |
            SVPD_ID_TYPE_TPORTGRP;
        desc->length = 4;
        if (softc->is_single ||
            (port && port->status & CTL_PORT_STATUS_HA_SHARED))
                g = 1;
        else
                g = 2 + ctsio->io_hdr.nexus.targ_port / softc->port_cnt;
        scsi_ulto2b(g, &desc->identifier[2]);
        desc = (struct scsi_vpd_id_descriptor *)(&desc->identifier[0] +
            sizeof(struct scsi_vpd_id_trgt_port_grp_id));

        /*
         * This is for the Target identifier
         */
        if (port && port->target_devid) {
                memcpy(desc, port->target_devid->data, port->target_devid->len);
        }

        ctl_set_success(ctsio);
        ctsio->io_hdr.flags |= CTL_FLAG_ALLOCATED;
        ctsio->be_move_done = ctl_config_move_done;
        ctl_datamove((union ctl_io *)ctsio);
        return (CTL_RETVAL_COMPLETE);
}

static int
ctl_inquiry_evpd_scsi_ports(struct ctl_scsiio *ctsio, int alloc_len)
{
        struct ctl_softc *softc = CTL_SOFTC(ctsio);
        struct ctl_lun *lun = CTL_LUN(ctsio);
        struct scsi_vpd_scsi_ports *sp;
        struct scsi_vpd_port_designation *pd;
        struct scsi_vpd_port_designation_cont *pdc;
        struct ctl_port *port;
        int data_len, num_target_ports, iid_len, id_len;

        num_target_ports = 0;
        iid_len = 0;
        id_len = 0;
        mtx_lock(&softc->ctl_lock);
        STAILQ_FOREACH(port, &softc->port_list, links) {
                if ((port->status & CTL_PORT_STATUS_ONLINE) == 0)
                        continue;
                if (lun != NULL &&
                    ctl_lun_map_to_port(port, lun->lun) == UINT32_MAX)
                        continue;
                num_target_ports++;
                if (port->init_devid)
                        iid_len += port->init_devid->len;
                if (port->port_devid)
                        id_len += port->port_devid->len;
        }
        mtx_unlock(&softc->ctl_lock);

        data_len = sizeof(struct scsi_vpd_scsi_ports) +
            num_target_ports * (sizeof(struct scsi_vpd_port_designation) +
             sizeof(struct scsi_vpd_port_designation_cont)) + iid_len + id_len;
        ctsio->kern_data_ptr = malloc(data_len, M_CTL, M_WAITOK | M_ZERO);
        sp = (struct scsi_vpd_scsi_ports *)ctsio->kern_data_ptr;
        ctsio->kern_sg_entries = 0;
        ctsio->kern_rel_offset = 0;
        ctsio->kern_sg_entries = 0;
        ctsio->kern_data_len = min(data_len, alloc_len);
        ctsio->kern_total_len = ctsio->kern_data_len;

        /*
         * The control device is always connected.  The disk device, on the
         * other hand, may not be online all the time.  Need to change this
         * to figure out whether the disk device is actually online or not.
         */
        if (lun != NULL)
                sp->device = (SID_QUAL_LU_CONNECTED << 5) |
                                  lun->be_lun->lun_type;
        else
                sp->device = (SID_QUAL_LU_OFFLINE << 5) | T_DIRECT;

        sp->page_code = SVPD_SCSI_PORTS;
        scsi_ulto2b(data_len - sizeof(struct scsi_vpd_scsi_ports),
            sp->page_length);
        pd = &sp->design[0];

        mtx_lock(&softc->ctl_lock);
        STAILQ_FOREACH(port, &softc->port_list, links) {
                if ((port->status & CTL_PORT_STATUS_ONLINE) == 0)
                        continue;
                if (lun != NULL &&
                    ctl_lun_map_to_port(port, lun->lun) == UINT32_MAX)
                        continue;
                scsi_ulto2b(port->targ_port, pd->relative_port_id);
                if (port->init_devid) {
                        iid_len = port->init_devid->len;
                        memcpy(pd->initiator_transportid,
                            port->init_devid->data, port->init_devid->len);
                } else
                        iid_len = 0;
                scsi_ulto2b(iid_len, pd->initiator_transportid_length);
                pdc = (struct scsi_vpd_port_designation_cont *)
                    (&pd->initiator_transportid[iid_len]);
                if (port->port_devid) {
                        id_len = port->port_devid->len;
                        memcpy(pdc->target_port_descriptors,
                            port->port_devid->data, port->port_devid->len);
                } else
                        id_len = 0;
                scsi_ulto2b(id_len, pdc->target_port_descriptors_length);
                pd = (struct scsi_vpd_port_designation *)
                    ((uint8_t *)pdc->target_port_descriptors + id_len);
        }
        mtx_unlock(&softc->ctl_lock);

        ctl_set_success(ctsio);
        ctsio->io_hdr.flags |= CTL_FLAG_ALLOCATED;
        ctsio->be_move_done = ctl_config_move_done;
        ctl_datamove((union ctl_io *)ctsio);
        return (CTL_RETVAL_COMPLETE);
}

static int
ctl_inquiry_evpd_sfs(struct ctl_scsiio *ctsio, int alloc_len)
{
        struct ctl_lun *lun = CTL_LUN(ctsio);
        struct scsi_vpd_sfs *sfs_ptr;
        int sfs_page_size, n;

        sfs_page_size = sizeof(*sfs_ptr) + 5 * 2;
        ctsio->kern_data_ptr = malloc(sfs_page_size, M_CTL, M_WAITOK | M_ZERO);
        sfs_ptr = (struct scsi_vpd_sfs *)ctsio->kern_data_ptr;
        ctsio->kern_sg_entries = 0;
        ctsio->kern_rel_offset = 0;
        ctsio->kern_sg_entries = 0;
        ctsio->kern_data_len = min(sfs_page_size, alloc_len);
        ctsio->kern_total_len = ctsio->kern_data_len;

        /*
         * The control device is always connected.  The disk device, on the
         * other hand, may not be online all the time.  Need to change this
         * to figure out whether the disk device is actually online or not.
         */
        if (lun != NULL)
                sfs_ptr->device = (SID_QUAL_LU_CONNECTED << 5) |
                                  lun->be_lun->lun_type;
        else
                sfs_ptr->device = (SID_QUAL_LU_OFFLINE << 5) | T_DIRECT;

        sfs_ptr->page_code = SVPD_SCSI_SFS;
        n = 0;
        /* Discovery 2016 */
        scsi_ulto2b(0x0001, &sfs_ptr->codes[2 * n++]);
        if (lun != NULL && lun->be_lun->lun_type == T_DIRECT) {
                 /* SBC Base 2016 */
                scsi_ulto2b(0x0101, &sfs_ptr->codes[2 * n++]);
                 /* SBC Base 2010 */
                scsi_ulto2b(0x0102, &sfs_ptr->codes[2 * n++]);
                if (lun->be_lun->flags & CTL_LUN_FLAG_UNMAP) {
                        /* Basic Provisioning 2016 */
                        scsi_ulto2b(0x0103, &sfs_ptr->codes[2 * n++]);
                }
                /* Drive Maintenance 2016 */
                //scsi_ulto2b(0x0104, &sfs_ptr->codes[2 * n++]);
        }
        scsi_ulto2b(4 + 2 * n, sfs_ptr->page_length);

        ctl_set_success(ctsio);
        ctsio->io_hdr.flags |= CTL_FLAG_ALLOCATED;
        ctsio->be_move_done = ctl_config_move_done;
        ctl_datamove((union ctl_io *)ctsio);
        return (CTL_RETVAL_COMPLETE);
}

static int
ctl_inquiry_evpd_block_limits(struct ctl_scsiio *ctsio, int alloc_len)
{
        struct ctl_lun *lun = CTL_LUN(ctsio);
        struct scsi_vpd_block_limits *bl_ptr;
        const char *val;
        uint64_t ival;

        ctsio->kern_data_ptr = malloc(sizeof(*bl_ptr), M_CTL, M_WAITOK | M_ZERO);
        bl_ptr = (struct scsi_vpd_block_limits *)ctsio->kern_data_ptr;
        ctsio->kern_sg_entries = 0;
        ctsio->kern_rel_offset = 0;
        ctsio->kern_sg_entries = 0;
        ctsio->kern_data_len = min(sizeof(*bl_ptr), alloc_len);
        ctsio->kern_total_len = ctsio->kern_data_len;

        /*
         * The control device is always connected.  The disk device, on the
         * other hand, may not be online all the time.  Need to change this
         * to figure out whether the disk device is actually online or not.
         */
        if (lun != NULL)
                bl_ptr->device = (SID_QUAL_LU_CONNECTED << 5) |
                                  lun->be_lun->lun_type;
        else
                bl_ptr->device = (SID_QUAL_LU_OFFLINE << 5) | T_DIRECT;

        bl_ptr->page_code = SVPD_BLOCK_LIMITS;
        scsi_ulto2b(sizeof(*bl_ptr) - 4, bl_ptr->page_length);
        bl_ptr->max_cmp_write_len = 0xff;
        scsi_ulto4b(0xffffffff, bl_ptr->max_txfer_len);
        if (lun != NULL) {
                scsi_ulto4b(lun->be_lun->opttxferlen, bl_ptr->opt_txfer_len);
                if (lun->be_lun->flags & CTL_LUN_FLAG_UNMAP) {
                        ival = 0xffffffff;
                        val = dnvlist_get_string(lun->be_lun->options,
                            "unmap_max_lba", NULL);
                        if (val != NULL)
                                ctl_expand_number(val, &ival);
                        scsi_ulto4b(ival, bl_ptr->max_unmap_lba_cnt);
                        ival = 0xffffffff;
                        val = dnvlist_get_string(lun->be_lun->options,
                            "unmap_max_descr", NULL);
                        if (val != NULL)
                                ctl_expand_number(val, &ival);
                        scsi_ulto4b(ival, bl_ptr->max_unmap_blk_cnt);
                        if (lun->be_lun->ublockexp != 0) {
                                scsi_ulto4b((1 << lun->be_lun->ublockexp),
                                    bl_ptr->opt_unmap_grain);
                                scsi_ulto4b(0x80000000 | lun->be_lun->ublockoff,
                                    bl_ptr->unmap_grain_align);
                        }
                }
                scsi_ulto4b(lun->be_lun->atomicblock,
                    bl_ptr->max_atomic_transfer_length);
                scsi_ulto4b(0, bl_ptr->atomic_alignment);
                scsi_ulto4b(0, bl_ptr->atomic_transfer_length_granularity);
                scsi_ulto4b(0, bl_ptr->max_atomic_transfer_length_with_atomic_boundary);
                scsi_ulto4b(0, bl_ptr->max_atomic_boundary_size);
                ival = UINT64_MAX;
                val = dnvlist_get_string(lun->be_lun->options,
                    "write_same_max_lba", NULL);
                if (val != NULL)
                        ctl_expand_number(val, &ival);
                scsi_u64to8b(ival, bl_ptr->max_write_same_length);
                if (lun->be_lun->maxlba + 1 > ival)
                        bl_ptr->flags |= SVPD_BL_WSNZ;
        }

        ctl_set_success(ctsio);
        ctsio->io_hdr.flags |= CTL_FLAG_ALLOCATED;
        ctsio->be_move_done = ctl_config_move_done;
        ctl_datamove((union ctl_io *)ctsio);
        return (CTL_RETVAL_COMPLETE);
}

static int
ctl_inquiry_evpd_bdc(struct ctl_scsiio *ctsio, int alloc_len)
{
        struct ctl_lun *lun = CTL_LUN(ctsio);
        struct scsi_vpd_block_device_characteristics *bdc_ptr;
        const char *value;
        u_int i;

        ctsio->kern_data_ptr = malloc(sizeof(*bdc_ptr), M_CTL, M_WAITOK | M_ZERO);
        bdc_ptr = (struct scsi_vpd_block_device_characteristics *)ctsio->kern_data_ptr;
        ctsio->kern_sg_entries = 0;
        ctsio->kern_rel_offset = 0;
        ctsio->kern_data_len = min(sizeof(*bdc_ptr), alloc_len);
        ctsio->kern_total_len = ctsio->kern_data_len;

        /*
         * The control device is always connected.  The disk device, on the
         * other hand, may not be online all the time.  Need to change this
         * to figure out whether the disk device is actually online or not.
         */
        if (lun != NULL)
                bdc_ptr->device = (SID_QUAL_LU_CONNECTED << 5) |
                                  lun->be_lun->lun_type;
        else
                bdc_ptr->device = (SID_QUAL_LU_OFFLINE << 5) | T_DIRECT;
        bdc_ptr->page_code = SVPD_BDC;
        scsi_ulto2b(sizeof(*bdc_ptr) - 4, bdc_ptr->page_length);
        if (lun != NULL &&
            (value = dnvlist_get_string(lun->be_lun->options, "rpm", NULL)) != NULL)
                i = strtol(value, NULL, 0);
        else
                i = CTL_DEFAULT_ROTATION_RATE;
        scsi_ulto2b(i, bdc_ptr->medium_rotation_rate);
        if (lun != NULL &&
            (value = dnvlist_get_string(lun->be_lun->options, "formfactor", NULL)) != NULL)
                i = strtol(value, NULL, 0);
        else
                i = 0;
        bdc_ptr->wab_wac_ff = (i & 0x0f);
        bdc_ptr->flags = SVPD_RBWZ | SVPD_FUAB | SVPD_VBULS;

        ctl_set_success(ctsio);
        ctsio->io_hdr.flags |= CTL_FLAG_ALLOCATED;
        ctsio->be_move_done = ctl_config_move_done;
        ctl_datamove((union ctl_io *)ctsio);
        return (CTL_RETVAL_COMPLETE);
}

static int
ctl_inquiry_evpd_lbp(struct ctl_scsiio *ctsio, int alloc_len)
{
        struct ctl_lun *lun = CTL_LUN(ctsio);
        struct scsi_vpd_logical_block_prov *lbp_ptr;
        const char *value;

        ctsio->kern_data_ptr = malloc(sizeof(*lbp_ptr), M_CTL, M_WAITOK | M_ZERO);
        lbp_ptr = (struct scsi_vpd_logical_block_prov *)ctsio->kern_data_ptr;
        ctsio->kern_sg_entries = 0;
        ctsio->kern_rel_offset = 0;
        ctsio->kern_data_len = min(sizeof(*lbp_ptr), alloc_len);
        ctsio->kern_total_len = ctsio->kern_data_len;

        /*
         * The control device is always connected.  The disk device, on the
         * other hand, may not be online all the time.  Need to change this
         * to figure out whether the disk device is actually online or not.
         */
        if (lun != NULL)
                lbp_ptr->device = (SID_QUAL_LU_CONNECTED << 5) |
                                  lun->be_lun->lun_type;
        else
                lbp_ptr->device = (SID_QUAL_LU_OFFLINE << 5) | T_DIRECT;

        lbp_ptr->page_code = SVPD_LBP;
        scsi_ulto2b(sizeof(*lbp_ptr) - 4, lbp_ptr->page_length);
        lbp_ptr->threshold_exponent = CTL_LBP_EXPONENT;
        if (lun != NULL && lun->be_lun->flags & CTL_LUN_FLAG_UNMAP) {
                lbp_ptr->flags = SVPD_LBP_UNMAP | SVPD_LBP_WS16 |
                    SVPD_LBP_WS10 | SVPD_LBP_RZ | SVPD_LBP_ANC_SUP;
                value = dnvlist_get_string(lun->be_lun->options,
                    "provisioning_type", NULL);
                if (value != NULL) {
                        if (strcmp(value, "resource") == 0)
                                lbp_ptr->prov_type = SVPD_LBP_RESOURCE;
                        else if (strcmp(value, "thin") == 0)
                                lbp_ptr->prov_type = SVPD_LBP_THIN;
                } else
                        lbp_ptr->prov_type = SVPD_LBP_THIN;
        }

        ctl_set_success(ctsio);
        ctsio->io_hdr.flags |= CTL_FLAG_ALLOCATED;
        ctsio->be_move_done = ctl_config_move_done;
        ctl_datamove((union ctl_io *)ctsio);
        return (CTL_RETVAL_COMPLETE);
}

/*
 * INQUIRY with the EVPD bit set.
 */
static int
ctl_inquiry_evpd(struct ctl_scsiio *ctsio)
{
        struct ctl_lun *lun = CTL_LUN(ctsio);
        struct scsi_inquiry *cdb;
        int alloc_len, retval;

        cdb = (struct scsi_inquiry *)ctsio->cdb;
        alloc_len = scsi_2btoul(cdb->length);

        switch (cdb->page_code) {
        case SVPD_SUPPORTED_PAGES:
                retval = ctl_inquiry_evpd_supported(ctsio, alloc_len);
                break;
        case SVPD_UNIT_SERIAL_NUMBER:
                retval = ctl_inquiry_evpd_serial(ctsio, alloc_len);
                break;
        case SVPD_DEVICE_ID:
                retval = ctl_inquiry_evpd_devid(ctsio, alloc_len);
                break;
        case SVPD_EXTENDED_INQUIRY_DATA:
                retval = ctl_inquiry_evpd_eid(ctsio, alloc_len);
                break;
        case SVPD_MODE_PAGE_POLICY:
                retval = ctl_inquiry_evpd_mpp(ctsio, alloc_len);
                break;
        case SVPD_SCSI_PORTS:
                retval = ctl_inquiry_evpd_scsi_ports(ctsio, alloc_len);
                break;
        case SVPD_SCSI_TPC:
                retval = ctl_inquiry_evpd_tpc(ctsio, alloc_len);
                break;
        case SVPD_SCSI_SFS:
                retval = ctl_inquiry_evpd_sfs(ctsio, alloc_len);
                break;
        case SVPD_BLOCK_LIMITS:
                if (lun == NULL || lun->be_lun->lun_type != T_DIRECT)
                        goto err;
                retval = ctl_inquiry_evpd_block_limits(ctsio, alloc_len);
                break;
        case SVPD_BDC:
                if (lun == NULL || lun->be_lun->lun_type != T_DIRECT)
                        goto err;
                retval = ctl_inquiry_evpd_bdc(ctsio, alloc_len);
                break;
        case SVPD_LBP:
                if (lun == NULL || lun->be_lun->lun_type != T_DIRECT)
                        goto err;
                retval = ctl_inquiry_evpd_lbp(ctsio, alloc_len);
                break;
        default:
err:
                ctl_set_invalid_field(ctsio,
                                      /*sks_valid*/ 1,
                                      /*command*/ 1,
                                      /*field*/ 2,
                                      /*bit_valid*/ 0,
                                      /*bit*/ 0);
                ctl_done((union ctl_io *)ctsio);
                retval = CTL_RETVAL_COMPLETE;
                break;
        }

        return (retval);
}

/*
 * Standard INQUIRY data.
 */
static int
ctl_inquiry_std(struct ctl_scsiio *ctsio)
{
        struct ctl_softc *softc = CTL_SOFTC(ctsio);
        struct ctl_port *port = CTL_PORT(ctsio);
        struct ctl_lun *lun = CTL_LUN(ctsio);
        struct scsi_inquiry_data *inq_ptr;
        struct scsi_inquiry *cdb;
        const char *val;
        uint32_t alloc_len, data_len;
        ctl_port_type port_type;

        port_type = port->port_type;
        if (port_type == CTL_PORT_IOCTL || port_type == CTL_PORT_INTERNAL)
                port_type = CTL_PORT_SCSI;

        cdb = (struct scsi_inquiry *)ctsio->cdb;
        alloc_len = scsi_2btoul(cdb->length);

        /*
         * We malloc the full inquiry data size here and fill it
         * in.  If the user only asks for less, we'll give him
         * that much.
         */
        data_len = offsetof(struct scsi_inquiry_data, vendor_specific1);
        ctsio->kern_data_ptr = malloc(data_len, M_CTL, M_WAITOK | M_ZERO);
        inq_ptr = (struct scsi_inquiry_data *)ctsio->kern_data_ptr;
        ctsio->kern_sg_entries = 0;
        ctsio->kern_rel_offset = 0;
        ctsio->kern_data_len = min(data_len, alloc_len);
        ctsio->kern_total_len = ctsio->kern_data_len;

        if (lun != NULL) {
                if ((lun->flags & CTL_LUN_PRIMARY_SC) ||
                    softc->ha_link >= CTL_HA_LINK_UNKNOWN) {
                        inq_ptr->device = (SID_QUAL_LU_CONNECTED << 5) |
                            lun->be_lun->lun_type;
                } else {
                        inq_ptr->device = (SID_QUAL_LU_OFFLINE << 5) |
                            lun->be_lun->lun_type;
                }
                if (lun->flags & CTL_LUN_REMOVABLE)
                        inq_ptr->dev_qual2 |= SID_RMB;
        } else
                inq_ptr->device = (SID_QUAL_BAD_LU << 5) | T_NODEVICE;

        /* RMB in byte 2 is 0 */
        inq_ptr->version = SCSI_REV_SPC5;

        /*
         * According to SAM-3, even if a device only supports a single
         * level of LUN addressing, it should still set the HISUP bit:
         *
         * 4.9.1 Logical unit numbers overview
         *
         * All logical unit number formats described in this standard are
         * hierarchical in structure even when only a single level in that
         * hierarchy is used. The HISUP bit shall be set to one in the
         * standard INQUIRY data (see SPC-2) when any logical unit number
         * format described in this standard is used.  Non-hierarchical
         * formats are outside the scope of this standard.
         *
         * Therefore we set the HiSup bit here.
         *
         * The response format is 2, per SPC-3.
         */
        inq_ptr->response_format = SID_HiSup | 2;

        inq_ptr->additional_length = data_len -
            (offsetof(struct scsi_inquiry_data, additional_length) + 1);
        CTL_DEBUG_PRINT(("additional_length = %d\n",
                         inq_ptr->additional_length));

        inq_ptr->spc3_flags = SPC3_SID_3PC | SPC3_SID_TPGS_IMPLICIT;
        if (port_type == CTL_PORT_SCSI)
                inq_ptr->spc2_flags = SPC2_SID_ADDR16;
        inq_ptr->spc2_flags |= SPC2_SID_MultiP;
        inq_ptr->flags = SID_CmdQue;
        if (port_type == CTL_PORT_SCSI)
                inq_ptr->flags |= SID_WBus16 | SID_Sync;

        /*
         * Per SPC-3, unused bytes in ASCII strings are filled with spaces.
         * We have 8 bytes for the vendor name, and 16 bytes for the device
         * name and 4 bytes for the revision.
         */
        if (lun == NULL || (val = dnvlist_get_string(lun->be_lun->options,
            "vendor", NULL)) == NULL) {
                strncpy(inq_ptr->vendor, CTL_VENDOR, sizeof(inq_ptr->vendor));
        } else {
                memset(inq_ptr->vendor, ' ', sizeof(inq_ptr->vendor));
                strncpy(inq_ptr->vendor, val,
                    min(sizeof(inq_ptr->vendor), strlen(val)));
        }
        if (lun == NULL) {
                strncpy(inq_ptr->product, CTL_DIRECT_PRODUCT,
                    sizeof(inq_ptr->product));
        } else if ((val = dnvlist_get_string(lun->be_lun->options, "product",
            NULL)) == NULL) {
                switch (lun->be_lun->lun_type) {
                case T_DIRECT:
                        strncpy(inq_ptr->product, CTL_DIRECT_PRODUCT,
                            sizeof(inq_ptr->product));
                        break;
                case T_PROCESSOR:
                        strncpy(inq_ptr->product, CTL_PROCESSOR_PRODUCT,
                            sizeof(inq_ptr->product));
                        break;
                case T_CDROM:
                        strncpy(inq_ptr->product, CTL_CDROM_PRODUCT,
                            sizeof(inq_ptr->product));
                        break;
                default:
                        strncpy(inq_ptr->product, CTL_UNKNOWN_PRODUCT,
                            sizeof(inq_ptr->product));
                        break;
                }
        } else {
                memset(inq_ptr->product, ' ', sizeof(inq_ptr->product));
                strncpy(inq_ptr->product, val,
                    min(sizeof(inq_ptr->product), strlen(val)));
        }

        /*
         * XXX make this a macro somewhere so it automatically gets
         * incremented when we make changes.
         */
        if (lun == NULL || (val = dnvlist_get_string(lun->be_lun->options,
            "revision", NULL)) == NULL) {
                strncpy(inq_ptr->revision, "0001", sizeof(inq_ptr->revision));
        } else {
                memset(inq_ptr->revision, ' ', sizeof(inq_ptr->revision));
                strncpy(inq_ptr->revision, val,
                    min(sizeof(inq_ptr->revision), strlen(val)));
        }

        /*
         * For parallel SCSI, we support double transition and single
         * transition clocking.  We also support QAS (Quick Arbitration
         * and Selection) and Information Unit transfers on both the
         * control and array devices.
         */
        if (port_type == CTL_PORT_SCSI)
                inq_ptr->spi3data = SID_SPI_CLOCK_DT_ST | SID_SPI_QAS |
                                    SID_SPI_IUS;

        /* SAM-6 (no version claimed) */
        scsi_ulto2b(0x00C0, inq_ptr->version1);
        /* SPC-5 (no version claimed) */
        scsi_ulto2b(0x05C0, inq_ptr->version2);
        if (port_type == CTL_PORT_FC) {
                /* FCP-2 ANSI INCITS.350:2003 */
                scsi_ulto2b(0x0917, inq_ptr->version3);
        } else if (port_type == CTL_PORT_SCSI) {
                /* SPI-4 ANSI INCITS.362:200x */
                scsi_ulto2b(0x0B56, inq_ptr->version3);
        } else if (port_type == CTL_PORT_ISCSI) {
                /* iSCSI (no version claimed) */
                scsi_ulto2b(0x0960, inq_ptr->version3);
        } else if (port_type == CTL_PORT_SAS) {
                /* SAS (no version claimed) */
                scsi_ulto2b(0x0BE0, inq_ptr->version3);
        } else if (port_type == CTL_PORT_UMASS) {
                /* USB Mass Storage Class Bulk-Only Transport, Revision 1.0 */
                scsi_ulto2b(0x1730, inq_ptr->version3);
        }

        if (lun == NULL) {
                /* SBC-4 (no version claimed) */
                scsi_ulto2b(0x0600, inq_ptr->version4);
        } else {
                switch (lun->be_lun->lun_type) {
                case T_DIRECT:
                        /* SBC-4 (no version claimed) */
                        scsi_ulto2b(0x0600, inq_ptr->version4);
                        break;
                case T_PROCESSOR:
                        break;
                case T_CDROM:
                        /* MMC-6 (no version claimed) */
                        scsi_ulto2b(0x04E0, inq_ptr->version4);
                        break;
                default:
                        break;
                }
        }

        ctl_set_success(ctsio);
        ctsio->io_hdr.flags |= CTL_FLAG_ALLOCATED;
        ctsio->be_move_done = ctl_config_move_done;
        ctl_datamove((union ctl_io *)ctsio);
        return (CTL_RETVAL_COMPLETE);
}

int
ctl_inquiry(struct ctl_scsiio *ctsio)
{
        struct scsi_inquiry *cdb;
        int retval;

        CTL_DEBUG_PRINT(("ctl_inquiry\n"));

        cdb = (struct scsi_inquiry *)ctsio->cdb;
        if (cdb->byte2 & SI_EVPD)
                retval = ctl_inquiry_evpd(ctsio);
        else if (cdb->page_code == 0)
                retval = ctl_inquiry_std(ctsio);
        else {
                ctl_set_invalid_field(ctsio,
                                      /*sks_valid*/ 1,
                                      /*command*/ 1,
                                      /*field*/ 2,
                                      /*bit_valid*/ 0,
                                      /*bit*/ 0);
                ctl_done((union ctl_io *)ctsio);
                return (CTL_RETVAL_COMPLETE);
        }

        return (retval);
}

int
ctl_get_config(struct ctl_scsiio *ctsio)
{
        struct ctl_lun *lun = CTL_LUN(ctsio);
        struct scsi_get_config_header *hdr;
        struct scsi_get_config_feature *feature;
        struct scsi_get_config *cdb;
        uint32_t alloc_len, data_len;
        int rt, starting;

        cdb = (struct scsi_get_config *)ctsio->cdb;
        rt = (cdb->rt & SGC_RT_MASK);
        starting = scsi_2btoul(cdb->starting_feature);
        alloc_len = scsi_2btoul(cdb->length);

        data_len = sizeof(struct scsi_get_config_header) +
            sizeof(struct scsi_get_config_feature) + 8 +
            sizeof(struct scsi_get_config_feature) + 8 +
            sizeof(struct scsi_get_config_feature) + 4 +
            sizeof(struct scsi_get_config_feature) + 4 +
            sizeof(struct scsi_get_config_feature) + 8 +
            sizeof(struct scsi_get_config_feature) +
            sizeof(struct scsi_get_config_feature) + 4 +
            sizeof(struct scsi_get_config_feature) + 4 +
            sizeof(struct scsi_get_config_feature) + 4 +
            sizeof(struct scsi_get_config_feature) + 4 +
            sizeof(struct scsi_get_config_feature) + 4 +
            sizeof(struct scsi_get_config_feature) + 4;
        ctsio->kern_data_ptr = malloc(data_len, M_CTL, M_WAITOK | M_ZERO);
        ctsio->kern_sg_entries = 0;
        ctsio->kern_rel_offset = 0;

        hdr = (struct scsi_get_config_header *)ctsio->kern_data_ptr;
        if (lun->flags & CTL_LUN_NO_MEDIA)
                scsi_ulto2b(0x0000, hdr->current_profile);
        else
                scsi_ulto2b(0x0010, hdr->current_profile);
        feature = (struct scsi_get_config_feature *)(hdr + 1);

        if (starting > 0x003b)
                goto done;
        if (starting > 0x003a)
                goto f3b;
        if (starting > 0x002b)
                goto f3a;
        if (starting > 0x002a)
                goto f2b;
        if (starting > 0x001f)
                goto f2a;
        if (starting > 0x001e)
                goto f1f;
        if (starting > 0x001d)
                goto f1e;
        if (starting > 0x0010)
                goto f1d;
        if (starting > 0x0003)
                goto f10;
        if (starting > 0x0002)
                goto f3;
        if (starting > 0x0001)
                goto f2;
        if (starting > 0x0000)
                goto f1;

        /* Profile List */
        scsi_ulto2b(0x0000, feature->feature_code);
        feature->flags = SGC_F_PERSISTENT | SGC_F_CURRENT;
        feature->add_length = 8;
        scsi_ulto2b(0x0008, &feature->feature_data[0]); /* CD-ROM */
        feature->feature_data[2] = 0x00;
        scsi_ulto2b(0x0010, &feature->feature_data[4]); /* DVD-ROM */
        feature->feature_data[6] = 0x01;
        feature = (struct scsi_get_config_feature *)
            &feature->feature_data[feature->add_length];

f1:     /* Core */
        scsi_ulto2b(0x0001, feature->feature_code);
        feature->flags = 0x08 | SGC_F_PERSISTENT | SGC_F_CURRENT;
        feature->add_length = 8;
        scsi_ulto4b(0x00000000, &feature->feature_data[0]);
        feature->feature_data[4] = 0x03;
        feature = (struct scsi_get_config_feature *)
            &feature->feature_data[feature->add_length];

f2:     /* Morphing */
        scsi_ulto2b(0x0002, feature->feature_code);
        feature->flags = 0x04 | SGC_F_PERSISTENT | SGC_F_CURRENT;
        feature->add_length = 4;
        feature->feature_data[0] = 0x02;
        feature = (struct scsi_get_config_feature *)
            &feature->feature_data[feature->add_length];

f3:     /* Removable Medium */
        scsi_ulto2b(0x0003, feature->feature_code);
        feature->flags = 0x04 | SGC_F_PERSISTENT | SGC_F_CURRENT;
        feature->add_length = 4;
        feature->feature_data[0] = 0x39;
        feature = (struct scsi_get_config_feature *)
            &feature->feature_data[feature->add_length];

        if (rt == SGC_RT_CURRENT && (lun->flags & CTL_LUN_NO_MEDIA))
                goto done;

f10:    /* Random Read */
        scsi_ulto2b(0x0010, feature->feature_code);
        feature->flags = 0x00;
        if ((lun->flags & CTL_LUN_NO_MEDIA) == 0)
                feature->flags |= SGC_F_CURRENT;
        feature->add_length = 8;
        scsi_ulto4b(lun->be_lun->blocksize, &feature->feature_data[0]);
        scsi_ulto2b(1, &feature->feature_data[4]);
        feature->feature_data[6] = 0x00;
        feature = (struct scsi_get_config_feature *)
            &feature->feature_data[feature->add_length];

f1d:    /* Multi-Read */
        scsi_ulto2b(0x001D, feature->feature_code);
        feature->flags = 0x00;
        if ((lun->flags & CTL_LUN_NO_MEDIA) == 0)
                feature->flags |= SGC_F_CURRENT;
        feature->add_length = 0;
        feature = (struct scsi_get_config_feature *)
            &feature->feature_data[feature->add_length];

f1e:    /* CD Read */
        scsi_ulto2b(0x001E, feature->feature_code);
        feature->flags = 0x00;
        if ((lun->flags & CTL_LUN_NO_MEDIA) == 0)
                feature->flags |= SGC_F_CURRENT;
        feature->add_length = 4;
        feature->feature_data[0] = 0x00;
        feature = (struct scsi_get_config_feature *)
            &feature->feature_data[feature->add_length];

f1f:    /* DVD Read */
        scsi_ulto2b(0x001F, feature->feature_code);
        feature->flags = 0x08;
        if ((lun->flags & CTL_LUN_NO_MEDIA) == 0)
                feature->flags |= SGC_F_CURRENT;
        feature->add_length = 4;
        feature->feature_data[0] = 0x01;
        feature->feature_data[2] = 0x03;
        feature = (struct scsi_get_config_feature *)
            &feature->feature_data[feature->add_length];

f2a:    /* DVD+RW */
        scsi_ulto2b(0x002A, feature->feature_code);
        feature->flags = 0x04;
        if ((lun->flags & CTL_LUN_NO_MEDIA) == 0)
                feature->flags |= SGC_F_CURRENT;
        feature->add_length = 4;
        feature->feature_data[0] = 0x00;
        feature->feature_data[1] = 0x00;
        feature = (struct scsi_get_config_feature *)
            &feature->feature_data[feature->add_length];

f2b:    /* DVD+R */
        scsi_ulto2b(0x002B, feature->feature_code);
        feature->flags = 0x00;
        if ((lun->flags & CTL_LUN_NO_MEDIA) == 0)
                feature->flags |= SGC_F_CURRENT;
        feature->add_length = 4;
        feature->feature_data[0] = 0x00;
        feature = (struct scsi_get_config_feature *)
            &feature->feature_data[feature->add_length];

f3a:    /* DVD+RW Dual Layer */
        scsi_ulto2b(0x003A, feature->feature_code);
        feature->flags = 0x00;
        if ((lun->flags & CTL_LUN_NO_MEDIA) == 0)
                feature->flags |= SGC_F_CURRENT;
        feature->add_length = 4;
        feature->feature_data[0] = 0x00;
        feature->feature_data[1] = 0x00;
        feature = (struct scsi_get_config_feature *)
            &feature->feature_data[feature->add_length];

f3b:    /* DVD+R Dual Layer */
        scsi_ulto2b(0x003B, feature->feature_code);
        feature->flags = 0x00;
        if ((lun->flags & CTL_LUN_NO_MEDIA) == 0)
                feature->flags |= SGC_F_CURRENT;
        feature->add_length = 4;
        feature->feature_data[0] = 0x00;
        feature = (struct scsi_get_config_feature *)
            &feature->feature_data[feature->add_length];

done:
        data_len = (uint8_t *)feature - (uint8_t *)hdr;
        if (rt == SGC_RT_SPECIFIC && data_len > 4) {
                feature = (struct scsi_get_config_feature *)(hdr + 1);
                if (scsi_2btoul(feature->feature_code) == starting)
                        feature = (struct scsi_get_config_feature *)
                            &feature->feature_data[feature->add_length];
                data_len = (uint8_t *)feature - (uint8_t *)hdr;
        }
        scsi_ulto4b(data_len - 4, hdr->data_length);
        ctsio->kern_data_len = min(data_len, alloc_len);
        ctsio->kern_total_len = ctsio->kern_data_len;

        ctl_set_success(ctsio);
        ctsio->io_hdr.flags |= CTL_FLAG_ALLOCATED;
        ctsio->be_move_done = ctl_config_move_done;
        ctl_datamove((union ctl_io *)ctsio);
        return (CTL_RETVAL_COMPLETE);
}

int
ctl_get_event_status(struct ctl_scsiio *ctsio)
{
        struct scsi_get_event_status_header *hdr;
        struct scsi_get_event_status *cdb;
        uint32_t alloc_len, data_len;

        cdb = (struct scsi_get_event_status *)ctsio->cdb;
        if ((cdb->byte2 & SGESN_POLLED) == 0) {
                ctl_set_invalid_field(ctsio, /*sks_valid*/ 1, /*command*/ 1,
                    /*field*/ 1, /*bit_valid*/ 1, /*bit*/ 0);
                ctl_done((union ctl_io *)ctsio);
                return (CTL_RETVAL_COMPLETE);
        }
        alloc_len = scsi_2btoul(cdb->length);

        data_len = sizeof(struct scsi_get_event_status_header);
        ctsio->kern_data_ptr = malloc(data_len, M_CTL, M_WAITOK | M_ZERO);
        ctsio->kern_sg_entries = 0;
        ctsio->kern_rel_offset = 0;
        ctsio->kern_data_len = min(data_len, alloc_len);
        ctsio->kern_total_len = ctsio->kern_data_len;

        hdr = (struct scsi_get_event_status_header *)ctsio->kern_data_ptr;
        scsi_ulto2b(0, hdr->descr_length);
        hdr->nea_class = SGESN_NEA;
        hdr->supported_class = 0;

        ctl_set_success(ctsio);
        ctsio->io_hdr.flags |= CTL_FLAG_ALLOCATED;
        ctsio->be_move_done = ctl_config_move_done;
        ctl_datamove((union ctl_io *)ctsio);
        return (CTL_RETVAL_COMPLETE);
}

int
ctl_mechanism_status(struct ctl_scsiio *ctsio)
{
        struct scsi_mechanism_status_header *hdr;
        struct scsi_mechanism_status *cdb;
        uint32_t alloc_len, data_len;

        cdb = (struct scsi_mechanism_status *)ctsio->cdb;
        alloc_len = scsi_2btoul(cdb->length);

        data_len = sizeof(struct scsi_mechanism_status_header);
        ctsio->kern_data_ptr = malloc(data_len, M_CTL, M_WAITOK | M_ZERO);
        ctsio->kern_sg_entries = 0;
        ctsio->kern_rel_offset = 0;
        ctsio->kern_data_len = min(data_len, alloc_len);
        ctsio->kern_total_len = ctsio->kern_data_len;

        hdr = (struct scsi_mechanism_status_header *)ctsio->kern_data_ptr;
        hdr->state1 = 0x00;
        hdr->state2 = 0xe0;
        scsi_ulto3b(0, hdr->lba);
        hdr->slots_num = 0;
        scsi_ulto2b(0, hdr->slots_length);

        ctl_set_success(ctsio);
        ctsio->io_hdr.flags |= CTL_FLAG_ALLOCATED;
        ctsio->be_move_done = ctl_config_move_done;
        ctl_datamove((union ctl_io *)ctsio);
        return (CTL_RETVAL_COMPLETE);
}

static void
ctl_ultomsf(uint32_t lba, uint8_t *buf)
{

        lba += 150;
        buf[0] = 0;
        buf[1] = bin2bcd((lba / 75) / 60);
        buf[2] = bin2bcd((lba / 75) % 60);
        buf[3] = bin2bcd(lba % 75);
}

int
ctl_read_toc(struct ctl_scsiio *ctsio)
{
        struct ctl_lun *lun = CTL_LUN(ctsio);
        struct scsi_read_toc_hdr *hdr;
        struct scsi_read_toc_type01_descr *descr;
        struct scsi_read_toc *cdb;
        uint32_t alloc_len, data_len;
        int format, msf;

        cdb = (struct scsi_read_toc *)ctsio->cdb;
        msf = (cdb->byte2 & CD_MSF) != 0;
        format = cdb->format;
        alloc_len = scsi_2btoul(cdb->data_len);

        data_len = sizeof(struct scsi_read_toc_hdr);
        if (format == 0)
                data_len += 2 * sizeof(struct scsi_read_toc_type01_descr);
        else
                data_len += sizeof(struct scsi_read_toc_type01_descr);
        ctsio->kern_data_ptr = malloc(data_len, M_CTL, M_WAITOK | M_ZERO);
        ctsio->kern_sg_entries = 0;
        ctsio->kern_rel_offset = 0;
        ctsio->kern_data_len = min(data_len, alloc_len);
        ctsio->kern_total_len = ctsio->kern_data_len;

        hdr = (struct scsi_read_toc_hdr *)ctsio->kern_data_ptr;
        if (format == 0) {
                scsi_ulto2b(0x12, hdr->data_length);
                hdr->first = 1;
                hdr->last = 1;
                descr = (struct scsi_read_toc_type01_descr *)(hdr + 1);
                descr->addr_ctl = 0x14;
                descr->track_number = 1;
                if (msf)
                        ctl_ultomsf(0, descr->track_start);
                else
                        scsi_ulto4b(0, descr->track_start);
                descr++;
                descr->addr_ctl = 0x14;
                descr->track_number = 0xaa;
                if (msf)
                        ctl_ultomsf(lun->be_lun->maxlba+1, descr->track_start);
                else
                        scsi_ulto4b(lun->be_lun->maxlba+1, descr->track_start);
        } else {
                scsi_ulto2b(0x0a, hdr->data_length);
                hdr->first = 1;
                hdr->last = 1;
                descr = (struct scsi_read_toc_type01_descr *)(hdr + 1);
                descr->addr_ctl = 0x14;
                descr->track_number = 1;
                if (msf)
                        ctl_ultomsf(0, descr->track_start);
                else
                        scsi_ulto4b(0, descr->track_start);
        }

        ctl_set_success(ctsio);
        ctsio->io_hdr.flags |= CTL_FLAG_ALLOCATED;
        ctsio->be_move_done = ctl_config_move_done;
        ctl_datamove((union ctl_io *)ctsio);
        return (CTL_RETVAL_COMPLETE);
}

/*
 * For known CDB types, parse the LBA and length.
 */
static int
ctl_get_lba_len(union ctl_io *io, uint64_t *lba, uint64_t *len)
{
        if (io->io_hdr.io_type != CTL_IO_SCSI)
                return (1);

        switch (io->scsiio.cdb[0]) {
        case COMPARE_AND_WRITE: {
                struct scsi_compare_and_write *cdb;

                cdb = (struct scsi_compare_and_write *)io->scsiio.cdb;

                *lba = scsi_8btou64(cdb->addr);
                *len = cdb->length;
                break;
        }
        case READ_6:
        case WRITE_6: {
                struct scsi_rw_6 *cdb;

                cdb = (struct scsi_rw_6 *)io->scsiio.cdb;

                *lba = scsi_3btoul(cdb->addr);
                /* only 5 bits are valid in the most significant address byte */
                *lba &= 0x1fffff;
                *len = cdb->length;
                break;
        }
        case READ_10:
        case WRITE_10: {
                struct scsi_rw_10 *cdb;

                cdb = (struct scsi_rw_10 *)io->scsiio.cdb;

                *lba = scsi_4btoul(cdb->addr);
                *len = scsi_2btoul(cdb->length);
                break;
        }
        case WRITE_VERIFY_10: {
                struct scsi_write_verify_10 *cdb;

                cdb = (struct scsi_write_verify_10 *)io->scsiio.cdb;

                *lba = scsi_4btoul(cdb->addr);
                *len = scsi_2btoul(cdb->length);
                break;
        }
        case READ_12:
        case WRITE_12: {
                struct scsi_rw_12 *cdb;

                cdb = (struct scsi_rw_12 *)io->scsiio.cdb;

                *lba = scsi_4btoul(cdb->addr);
                *len = scsi_4btoul(cdb->length);
                break;
        }
        case WRITE_VERIFY_12: {
                struct scsi_write_verify_12 *cdb;

                cdb = (struct scsi_write_verify_12 *)io->scsiio.cdb;

                *lba = scsi_4btoul(cdb->addr);
                *len = scsi_4btoul(cdb->length);
                break;
        }
        case READ_16:
        case WRITE_16: {
                struct scsi_rw_16 *cdb;

                cdb = (struct scsi_rw_16 *)io->scsiio.cdb;

                *lba = scsi_8btou64(cdb->addr);
                *len = scsi_4btoul(cdb->length);
                break;
        }
        case WRITE_ATOMIC_16: {
                struct scsi_write_atomic_16 *cdb;

                cdb = (struct scsi_write_atomic_16 *)io->scsiio.cdb;

                *lba = scsi_8btou64(cdb->addr);
                *len = scsi_2btoul(cdb->length);
                break;
        }
        case WRITE_VERIFY_16: {
                struct scsi_write_verify_16 *cdb;

                cdb = (struct scsi_write_verify_16 *)io->scsiio.cdb;

                *lba = scsi_8btou64(cdb->addr);
                *len = scsi_4btoul(cdb->length);
                break;
        }
        case WRITE_SAME_10: {
                struct scsi_write_same_10 *cdb;

                cdb = (struct scsi_write_same_10 *)io->scsiio.cdb;

                *lba = scsi_4btoul(cdb->addr);
                *len = scsi_2btoul(cdb->length);
                break;
        }
        case WRITE_SAME_16: {
                struct scsi_write_same_16 *cdb;

                cdb = (struct scsi_write_same_16 *)io->scsiio.cdb;

                *lba = scsi_8btou64(cdb->addr);
                *len = scsi_4btoul(cdb->length);
                break;
        }
        case VERIFY_10: {
                struct scsi_verify_10 *cdb;

                cdb = (struct scsi_verify_10 *)io->scsiio.cdb;

                *lba = scsi_4btoul(cdb->addr);
                *len = scsi_2btoul(cdb->length);
                break;
        }
        case VERIFY_12: {
                struct scsi_verify_12 *cdb;

                cdb = (struct scsi_verify_12 *)io->scsiio.cdb;

                *lba = scsi_4btoul(cdb->addr);
                *len = scsi_4btoul(cdb->length);
                break;
        }
        case VERIFY_16: {
                struct scsi_verify_16 *cdb;

                cdb = (struct scsi_verify_16 *)io->scsiio.cdb;

                *lba = scsi_8btou64(cdb->addr);
                *len = scsi_4btoul(cdb->length);
                break;
        }
        case UNMAP: {
                *lba = 0;
                *len = UINT64_MAX;
                break;
        }
        case SERVICE_ACTION_IN: {       /* GET LBA STATUS */
                struct scsi_get_lba_status *cdb;

                cdb = (struct scsi_get_lba_status *)io->scsiio.cdb;
                *lba = scsi_8btou64(cdb->addr);
                *len = UINT32_MAX;
                break;
        }
        default:
                return (1);
                break; /* NOTREACHED */
        }

        return (0);
}

static ctl_action
ctl_extent_check_lba(uint64_t lba1, uint64_t len1, uint64_t lba2, uint64_t len2,
    bool seq)
{
        uint64_t endlba1, endlba2;

        endlba1 = lba1 + len1 - (seq ? 0 : 1);
        endlba2 = lba2 + len2 - 1;

        if ((endlba1 < lba2) || (endlba2 < lba1))
                return (CTL_ACTION_PASS);
        else
                return (CTL_ACTION_BLOCK);
}

static int
ctl_extent_check_unmap(union ctl_io *io, uint64_t lba2, uint64_t len2)
{
        struct ctl_ptr_len_flags *ptrlen;
        struct scsi_unmap_desc *buf, *end, *range;
        uint64_t lba;
        uint32_t len;

        /* If not UNMAP -- go other way. */
        if (io->io_hdr.io_type != CTL_IO_SCSI ||
            io->scsiio.cdb[0] != UNMAP)
                return (CTL_ACTION_ERROR);

        /* If UNMAP without data -- block and wait for data. */
        ptrlen = (struct ctl_ptr_len_flags *)
            &io->io_hdr.ctl_private[CTL_PRIV_LBA_LEN];
        if ((io->io_hdr.flags & CTL_FLAG_ALLOCATED) == 0 ||
            ptrlen->ptr == NULL)
                return (CTL_ACTION_BLOCK);

        /* UNMAP with data -- check for collision. */
        buf = (struct scsi_unmap_desc *)ptrlen->ptr;
        end = buf + ptrlen->len / sizeof(*buf);
        for (range = buf; range < end; range++) {
                lba = scsi_8btou64(range->lba);
                len = scsi_4btoul(range->length);
                if ((lba < lba2 + len2) && (lba + len > lba2))
                        return (CTL_ACTION_BLOCK);
        }
        return (CTL_ACTION_PASS);
}

static ctl_action
ctl_extent_check(union ctl_io *io1, union ctl_io *io2, bool seq)
{
        uint64_t lba1, lba2;
        uint64_t len1, len2;
        int retval;

        if (ctl_get_lba_len(io2, &lba2, &len2) != 0)
                return (CTL_ACTION_ERROR);

        retval = ctl_extent_check_unmap(io1, lba2, len2);
        if (retval != CTL_ACTION_ERROR)
                return (retval);

        if (ctl_get_lba_len(io1, &lba1, &len1) != 0)
                return (CTL_ACTION_ERROR);

        if (io1->io_hdr.flags & CTL_FLAG_SERSEQ_DONE)
                seq = FALSE;
        return (ctl_extent_check_lba(lba1, len1, lba2, len2, seq));
}

static ctl_action
ctl_extent_check_seq(union ctl_io *io1, union ctl_io *io2)
{
        uint64_t lba1, lba2;
        uint64_t len1, len2;

        if (io1->io_hdr.flags & CTL_FLAG_SERSEQ_DONE)
                return (CTL_ACTION_PASS);
        if (ctl_get_lba_len(io1, &lba1, &len1) != 0)
                return (CTL_ACTION_ERROR);
        if (ctl_get_lba_len(io2, &lba2, &len2) != 0)
                return (CTL_ACTION_ERROR);

        if (lba1 + len1 == lba2)
                return (CTL_ACTION_BLOCK);
        return (CTL_ACTION_PASS);
}

static ctl_action
ctl_check_for_blockage(struct ctl_lun *lun, union ctl_io *pending_io,
    union ctl_io *ooa_io)
{
        const struct ctl_cmd_entry *pending_entry, *ooa_entry;
        const ctl_serialize_action *serialize_row;

        /*
         * Aborted commands are not going to be executed and may even
         * not report completion, so we don't care about their order.
         * Let them complete ASAP to clean the OOA queue.
         */
        if (pending_io->io_hdr.flags & CTL_FLAG_ABORT)
                return (CTL_ACTION_SKIP);

        /*
         * The initiator attempted multiple untagged commands at the same
         * time.  Can't do that.
         */
        if ((pending_io->scsiio.tag_type == CTL_TAG_UNTAGGED)
         && (ooa_io->scsiio.tag_type == CTL_TAG_UNTAGGED)
         && ((pending_io->io_hdr.nexus.targ_port ==
              ooa_io->io_hdr.nexus.targ_port)
          && (pending_io->io_hdr.nexus.initid ==
              ooa_io->io_hdr.nexus.initid))
         && ((ooa_io->io_hdr.flags & (CTL_FLAG_ABORT |
              CTL_FLAG_STATUS_SENT)) == 0))
                return (CTL_ACTION_OVERLAP);

        /*
         * The initiator attempted to send multiple tagged commands with
         * the same ID.  (It's fine if different initiators have the same
         * tag ID.)
         *
         * Even if all of those conditions are true, we don't kill the I/O
         * if the command ahead of us has been aborted.  We won't end up
         * sending it to the FETD, and it's perfectly legal to resend a
         * command with the same tag number as long as the previous
         * instance of this tag number has been aborted somehow.
         */
        if ((pending_io->scsiio.tag_type != CTL_TAG_UNTAGGED)
         && (ooa_io->scsiio.tag_type != CTL_TAG_UNTAGGED)
         && (pending_io->scsiio.tag_num == ooa_io->scsiio.tag_num)
         && ((pending_io->io_hdr.nexus.targ_port ==
              ooa_io->io_hdr.nexus.targ_port)
          && (pending_io->io_hdr.nexus.initid ==
              ooa_io->io_hdr.nexus.initid))
         && ((ooa_io->io_hdr.flags & (CTL_FLAG_ABORT |
              CTL_FLAG_STATUS_SENT)) == 0))
                return (CTL_ACTION_OVERLAP_TAG);

        /*
         * If we get a head of queue tag, SAM-3 says that we should
         * immediately execute it.
         *
         * What happens if this command would normally block for some other
         * reason?  e.g. a request sense with a head of queue tag
         * immediately after a write.  Normally that would block, but this
         * will result in its getting executed immediately...
         *
         * We currently return "pass" instead of "skip", so we'll end up
         * going through the rest of the queue to check for overlapped tags.
         *
         * XXX KDM check for other types of blockage first??
         */
        if (pending_io->scsiio.tag_type == CTL_TAG_HEAD_OF_QUEUE)
                return (CTL_ACTION_PASS);

        /*
         * Ordered tags have to block until all items ahead of them
         * have completed.  If we get called with an ordered tag, we always
         * block, if something else is ahead of us in the queue.
         */
        if (pending_io->scsiio.tag_type == CTL_TAG_ORDERED)
                return (CTL_ACTION_BLOCK);

        /*
         * Simple tags get blocked until all head of queue and ordered tags
         * ahead of them have completed.  I'm lumping untagged commands in
         * with simple tags here.  XXX KDM is that the right thing to do?
         */
        if (((pending_io->scsiio.tag_type == CTL_TAG_UNTAGGED)
          || (pending_io->scsiio.tag_type == CTL_TAG_SIMPLE))
         && ((ooa_io->scsiio.tag_type == CTL_TAG_HEAD_OF_QUEUE)
          || (ooa_io->scsiio.tag_type == CTL_TAG_ORDERED)))
                return (CTL_ACTION_BLOCK);

        pending_entry = ctl_get_cmd_entry(&pending_io->scsiio, NULL);
        KASSERT(pending_entry->seridx < CTL_SERIDX_COUNT,
            ("%s: Invalid seridx %d for pending CDB %02x %02x @ %p",
             __func__, pending_entry->seridx, pending_io->scsiio.cdb[0],
             pending_io->scsiio.cdb[1], pending_io));
        ooa_entry = ctl_get_cmd_entry(&ooa_io->scsiio, NULL);
        if (ooa_entry->seridx == CTL_SERIDX_INVLD)
                return (CTL_ACTION_PASS); /* Unsupported command in OOA queue */
        KASSERT(ooa_entry->seridx < CTL_SERIDX_COUNT,
            ("%s: Invalid seridx %d for ooa CDB %02x %02x @ %p",
             __func__, ooa_entry->seridx, ooa_io->scsiio.cdb[0],
             ooa_io->scsiio.cdb[1], ooa_io));

        serialize_row = ctl_serialize_table[ooa_entry->seridx];

        switch (serialize_row[pending_entry->seridx]) {
        case CTL_SER_BLOCK:
                return (CTL_ACTION_BLOCK);
        case CTL_SER_EXTENT:
                return (ctl_extent_check(ooa_io, pending_io,
                    (lun->be_lun && lun->be_lun->serseq == CTL_LUN_SERSEQ_ON)));
        case CTL_SER_EXTENTOPT:
                if ((lun->MODE_CTRL.queue_flags & SCP_QUEUE_ALG_MASK) !=
                    SCP_QUEUE_ALG_UNRESTRICTED)
                        return (ctl_extent_check(ooa_io, pending_io,
                            (lun->be_lun &&
                             lun->be_lun->serseq == CTL_LUN_SERSEQ_ON)));
                return (CTL_ACTION_PASS);
        case CTL_SER_EXTENTSEQ:
                if (lun->be_lun && lun->be_lun->serseq != CTL_LUN_SERSEQ_OFF)
                        return (ctl_extent_check_seq(ooa_io, pending_io));
                return (CTL_ACTION_PASS);
        case CTL_SER_PASS:
                return (CTL_ACTION_PASS);
        case CTL_SER_BLOCKOPT:
                if ((lun->MODE_CTRL.queue_flags & SCP_QUEUE_ALG_MASK) !=
                    SCP_QUEUE_ALG_UNRESTRICTED)
                        return (CTL_ACTION_BLOCK);
                return (CTL_ACTION_PASS);
        case CTL_SER_SKIP:
                return (CTL_ACTION_SKIP);
        default:
                panic("%s: Invalid serialization value %d for %d => %d",
                    __func__, serialize_row[pending_entry->seridx],
                    pending_entry->seridx, ooa_entry->seridx);
        }

        return (CTL_ACTION_ERROR);
}

/*
 * Check for blockage or overlaps against the OOA (Order Of Arrival) queue.
 * Assumptions:
 * - pending_io is generally either incoming, or on the blocked queue
 * - starting I/O is the I/O we want to start the check with.
 */
static ctl_action
ctl_check_ooa(struct ctl_lun *lun, union ctl_io *pending_io,
              union ctl_io **starting_io)
{
        union ctl_io *ooa_io;
        ctl_action action;

        mtx_assert(&lun->lun_lock, MA_OWNED);

        /*
         * Run back along the OOA queue, starting with the current
         * blocked I/O and going through every I/O before it on the
         * queue.  If starting_io is NULL, we'll just end up returning
         * CTL_ACTION_PASS.
         */
        for (ooa_io = *starting_io; ooa_io != NULL;
             ooa_io = (union ctl_io *)TAILQ_PREV(&ooa_io->io_hdr, ctl_ooaq,
             ooa_links)){
                action = ctl_check_for_blockage(lun, pending_io, ooa_io);
                if (action != CTL_ACTION_PASS) {
                        *starting_io = ooa_io;
                        return (action);
                }
        }

        *starting_io = NULL;
        return (CTL_ACTION_PASS);
}

/*
 * Try to unblock the specified I/O.
 *
 * skip parameter allows explicitly skip present blocker of the I/O,
 * starting from the previous one on OOA queue.  It can be used when
 * we know for sure that the blocker I/O does no longer count.
 */
static void
ctl_try_unblock_io(struct ctl_lun *lun, union ctl_io *io, bool skip)
{
        struct ctl_softc *softc = lun->ctl_softc;
        union ctl_io *bio, *obio;
        const struct ctl_cmd_entry *entry;
        union ctl_ha_msg msg_info;
        ctl_action action;

        mtx_assert(&lun->lun_lock, MA_OWNED);

        if (io->io_hdr.blocker == NULL)
                return;

        obio = bio = io->io_hdr.blocker;
        if (skip)
                bio = (union ctl_io *)TAILQ_PREV(&bio->io_hdr, ctl_ooaq,
                    ooa_links);
        action = ctl_check_ooa(lun, io, &bio);
        if (action == CTL_ACTION_BLOCK) {
                /* Still blocked, but may be by different I/O now. */
                if (bio != obio) {
                        TAILQ_REMOVE(&obio->io_hdr.blocked_queue,
                            &io->io_hdr, blocked_links);
                        TAILQ_INSERT_TAIL(&bio->io_hdr.blocked_queue,
                            &io->io_hdr, blocked_links);
                        io->io_hdr.blocker = bio;
                }
                return;
        }

        /* No longer blocked, one way or another. */
        TAILQ_REMOVE(&obio->io_hdr.blocked_queue, &io->io_hdr, blocked_links);
        io->io_hdr.blocker = NULL;

        switch (action) {
        case CTL_ACTION_OVERLAP:
                ctl_set_overlapped_cmd(&io->scsiio);
                goto error;
        case CTL_ACTION_OVERLAP_TAG:
                ctl_set_overlapped_tag(&io->scsiio,
                    io->scsiio.tag_num & 0xff);
                goto error;
        case CTL_ACTION_PASS:
        case CTL_ACTION_SKIP:

                /* Serializing commands from the other SC retire there. */
                if ((io->io_hdr.flags & CTL_FLAG_FROM_OTHER_SC) &&
                    (softc->ha_mode != CTL_HA_MODE_XFER)) {
                        io->io_hdr.flags &= ~CTL_FLAG_IO_ACTIVE;
                        msg_info.hdr.original_sc = io->io_hdr.remote_io;
                        msg_info.hdr.serializing_sc = io;
                        msg_info.hdr.msg_type = CTL_MSG_R2R;
                        ctl_ha_msg_send(CTL_HA_CHAN_CTL, &msg_info,
                            sizeof(msg_info.hdr), M_NOWAIT);
                        break;
                }

                /*
                 * Check this I/O for LUN state changes that may have happened
                 * while this command was blocked. The LUN state may have been
                 * changed by a command ahead of us in the queue.
                 */
                entry = ctl_get_cmd_entry(&io->scsiio, NULL);
                if (ctl_scsiio_lun_check(lun, entry, &io->scsiio) != 0) {
                        ctl_done(io);
                        break;
                }

                io->io_hdr.flags |= CTL_FLAG_IS_WAS_ON_RTR;
                ctl_enqueue_rtr(io);
                break;
        case CTL_ACTION_ERROR:
        default:
                ctl_set_internal_failure(&io->scsiio,
                                         /*sks_valid*/ 0,
                                         /*retry_count*/ 0);

error:
                /* Serializing commands from the other SC are done here. */
                if ((io->io_hdr.flags & CTL_FLAG_FROM_OTHER_SC) &&
                    (softc->ha_mode != CTL_HA_MODE_XFER)) {
                        ctl_try_unblock_others(lun, io, TRUE);
                        TAILQ_REMOVE(&lun->ooa_queue, &io->io_hdr, ooa_links);

                        ctl_copy_sense_data_back(io, &msg_info);
                        msg_info.hdr.original_sc = io->io_hdr.remote_io;
                        msg_info.hdr.serializing_sc = NULL;
                        msg_info.hdr.msg_type = CTL_MSG_BAD_JUJU;
                        ctl_ha_msg_send(CTL_HA_CHAN_CTL, &msg_info,
                            sizeof(msg_info.scsi), M_WAITOK);
                        ctl_free_io(io);
                        break;
                }

                ctl_done(io);
                break;
        }
}

/*
 * Try to unblock I/Os blocked by the specified I/O.
 *
 * skip parameter allows explicitly skip the specified I/O as blocker,
 * starting from the previous one on the OOA queue.  It can be used when
 * we know for sure that the specified I/O does no longer count (done).
 * It has to be still on OOA queue though so that we know where to start.
 */
static void
ctl_try_unblock_others(struct ctl_lun *lun, union ctl_io *bio, bool skip)
{
        union ctl_io *io, *next_io;

        mtx_assert(&lun->lun_lock, MA_OWNED);

        for (io = (union ctl_io *)TAILQ_FIRST(&bio->io_hdr.blocked_queue);
             io != NULL; io = next_io) {
                next_io = (union ctl_io *)TAILQ_NEXT(&io->io_hdr, blocked_links);

                KASSERT(io->io_hdr.blocker != NULL,
                    ("I/O %p on blocked list without blocker", io));
                ctl_try_unblock_io(lun, io, skip);
        }
        KASSERT(!skip || TAILQ_EMPTY(&bio->io_hdr.blocked_queue),
            ("blocked_queue is not empty after skipping %p", bio));
}

/*
 * This routine (with one exception) checks LUN flags that can be set by
 * commands ahead of us in the OOA queue.  These flags have to be checked
 * when a command initially comes in, and when we pull a command off the
 * blocked queue and are preparing to execute it.  The reason we have to
 * check these flags for commands on the blocked queue is that the LUN
 * state may have been changed by a command ahead of us while we're on the
 * blocked queue.
 *
 * Ordering is somewhat important with these checks, so please pay
 * careful attention to the placement of any new checks.
 */
static int
ctl_scsiio_lun_check(struct ctl_lun *lun,
    const struct ctl_cmd_entry *entry, struct ctl_scsiio *ctsio)
{
        struct ctl_softc *softc = lun->ctl_softc;
        int retval;
        uint32_t residx;

        retval = 0;

        mtx_assert(&lun->lun_lock, MA_OWNED);

        /*
         * If this shelf is a secondary shelf controller, we may have to
         * reject some commands disallowed by HA mode and link state.
         */
        if ((lun->flags & CTL_LUN_PRIMARY_SC) == 0) {
                if (softc->ha_link == CTL_HA_LINK_OFFLINE &&
                    (entry->flags & CTL_CMD_FLAG_OK_ON_UNAVAIL) == 0) {
                        ctl_set_lun_unavail(ctsio);
                        retval = 1;
                        goto bailout;
                }
                if ((lun->flags & CTL_LUN_PEER_SC_PRIMARY) == 0 &&
                    (entry->flags & CTL_CMD_FLAG_OK_ON_UNAVAIL) == 0) {
                        ctl_set_lun_transit(ctsio);
                        retval = 1;
                        goto bailout;
                }
                if (softc->ha_mode == CTL_HA_MODE_ACT_STBY &&
                    (entry->flags & CTL_CMD_FLAG_OK_ON_STANDBY) == 0) {
                        ctl_set_lun_standby(ctsio);
                        retval = 1;
                        goto bailout;
                }

                /* The rest of checks are only done on executing side */
                if (softc->ha_mode == CTL_HA_MODE_XFER)
                        goto bailout;
        }

        if (entry->pattern & CTL_LUN_PAT_WRITE) {
                if (lun->be_lun &&
                    lun->be_lun->flags & CTL_LUN_FLAG_READONLY) {
                        ctl_set_hw_write_protected(ctsio);
                        retval = 1;
                        goto bailout;
                }
                if ((lun->MODE_CTRL.eca_and_aen & SCP_SWP) != 0) {
                        ctl_set_sense(ctsio, /*current_error*/ 1,
                            /*sense_key*/ SSD_KEY_DATA_PROTECT,
                            /*asc*/ 0x27, /*ascq*/ 0x02, SSD_ELEM_NONE);
                        retval = 1;
                        goto bailout;
                }
        }

        /*
         * Check for a reservation conflict.  If this command isn't allowed
         * even on reserved LUNs, and if this initiator isn't the one who
         * reserved us, reject the command with a reservation conflict.
         */
        residx = ctl_get_initindex(&ctsio->io_hdr.nexus);
        if ((lun->flags & CTL_LUN_RESERVED)
         && ((entry->flags & CTL_CMD_FLAG_ALLOW_ON_RESV) == 0)) {
                if (lun->res_idx != residx) {
                        ctl_set_reservation_conflict(ctsio);
                        retval = 1;
                        goto bailout;
                }
        }

        if ((lun->flags & CTL_LUN_PR_RESERVED) == 0 ||
            (entry->flags & CTL_CMD_FLAG_ALLOW_ON_PR_RESV)) {
                /* No reservation or command is allowed. */;
        } else if ((entry->flags & CTL_CMD_FLAG_ALLOW_ON_PR_WRESV) &&
            (lun->pr_res_type == SPR_TYPE_WR_EX ||
             lun->pr_res_type == SPR_TYPE_WR_EX_RO ||
             lun->pr_res_type == SPR_TYPE_WR_EX_AR)) {
                /* The command is allowed for Write Exclusive resv. */;
        } else {
                /*
                 * if we aren't registered or it's a res holder type
                 * reservation and this isn't the res holder then set a
                 * conflict.
                 */
                if (ctl_get_prkey(lun, residx) == 0 ||
                    (residx != lun->pr_res_idx && lun->pr_res_type < 4)) {
                        ctl_set_reservation_conflict(ctsio);
                        retval = 1;
                        goto bailout;
                }
        }

        if ((entry->flags & CTL_CMD_FLAG_OK_ON_NO_MEDIA) == 0) {
                if (lun->flags & CTL_LUN_EJECTED)
                        ctl_set_lun_ejected(ctsio);
                else if (lun->flags & CTL_LUN_NO_MEDIA) {
                        if (lun->flags & CTL_LUN_REMOVABLE)
                                ctl_set_lun_no_media(ctsio);
                        else
                                ctl_set_lun_int_reqd(ctsio);
                } else if (lun->flags & CTL_LUN_STOPPED)
                        ctl_set_lun_stopped(ctsio);
                else
                        goto bailout;
                retval = 1;
                goto bailout;
        }

bailout:
        return (retval);
}

static void
ctl_failover_io(union ctl_io *io, int have_lock)
{
        ctl_set_busy(&io->scsiio);
        ctl_done(io);
}

static void
ctl_failover_lun(union ctl_io *rio)
{
        struct ctl_softc *softc = CTL_SOFTC(rio);
        struct ctl_lun *lun;
        struct ctl_io_hdr *io, *next_io;
        uint32_t targ_lun;

        targ_lun = rio->io_hdr.nexus.targ_mapped_lun;
        CTL_DEBUG_PRINT(("FAILOVER for lun %u\n", targ_lun));

        /* Find and lock the LUN. */
        mtx_lock(&softc->ctl_lock);
        if (targ_lun > ctl_max_luns ||
            (lun = softc->ctl_luns[targ_lun]) == NULL) {
                mtx_unlock(&softc->ctl_lock);
                return;
        }
        mtx_lock(&lun->lun_lock);
        mtx_unlock(&softc->ctl_lock);
        if (lun->flags & CTL_LUN_DISABLED) {
                mtx_unlock(&lun->lun_lock);
                return;
        }

        if (softc->ha_mode == CTL_HA_MODE_XFER) {
                TAILQ_FOREACH_SAFE(io, &lun->ooa_queue, ooa_links, next_io) {
                        /* We are master */
                        if (io->flags & CTL_FLAG_FROM_OTHER_SC) {
                                if (io->flags & CTL_FLAG_IO_ACTIVE) {
                                        io->flags |= CTL_FLAG_ABORT;
                                        io->flags |= CTL_FLAG_FAILOVER;
                                        ctl_try_unblock_io(lun,
                                            (union ctl_io *)io, FALSE);
                                } else { /* This can be only due to DATAMOVE */
                                        io->msg_type = CTL_MSG_DATAMOVE_DONE;
                                        io->flags &= ~CTL_FLAG_DMA_INPROG;
                                        io->flags |= CTL_FLAG_IO_ACTIVE;
                                        io->port_status = 31340;
                                        ctl_enqueue_isc((union ctl_io *)io);
                                }
                        } else
                        /* We are slave */
                        if (io->flags & CTL_FLAG_SENT_2OTHER_SC) {
                                io->flags &= ~CTL_FLAG_SENT_2OTHER_SC;
                                if (io->flags & CTL_FLAG_IO_ACTIVE) {
                                        io->flags |= CTL_FLAG_FAILOVER;
                                } else {
                                        ctl_set_busy(&((union ctl_io *)io)->
                                            scsiio);
                                        ctl_done((union ctl_io *)io);
                                }
                        }
                }
        } else { /* SERIALIZE modes */
                TAILQ_FOREACH_SAFE(io, &lun->ooa_queue, ooa_links, next_io) {
                        /* We are master */
                        if (io->flags & CTL_FLAG_FROM_OTHER_SC) {
                                if (io->blocker != NULL) {
                                        TAILQ_REMOVE(&io->blocker->io_hdr.blocked_queue,
                                            io, blocked_links);
                                        io->blocker = NULL;
                                }
                                ctl_try_unblock_others(lun, (union ctl_io *)io,
                                    TRUE);
                                TAILQ_REMOVE(&lun->ooa_queue, io, ooa_links);
                                ctl_free_io((union ctl_io *)io);
                        } else
                        /* We are slave */
                        if (io->flags & CTL_FLAG_SENT_2OTHER_SC) {
                                io->flags &= ~CTL_FLAG_SENT_2OTHER_SC;
                                if (!(io->flags & CTL_FLAG_IO_ACTIVE)) {
                                        ctl_set_busy(&((union ctl_io *)io)->
                                            scsiio);
                                        ctl_done((union ctl_io *)io);
                                }
                        }
                }
        }
        mtx_unlock(&lun->lun_lock);
}

static int
ctl_scsiio_precheck(struct ctl_softc *softc, struct ctl_scsiio *ctsio)
{
        struct ctl_lun *lun;
        const struct ctl_cmd_entry *entry;
        union ctl_io *bio;
        uint32_t initidx, targ_lun;
        int retval = 0;

        lun = NULL;
        targ_lun = ctsio->io_hdr.nexus.targ_mapped_lun;
        if (targ_lun < ctl_max_luns)
                lun = softc->ctl_luns[targ_lun];
        if (lun) {
                /*
                 * If the LUN is invalid, pretend that it doesn't exist.
                 * It will go away as soon as all pending I/O has been
                 * completed.
                 */
                mtx_lock(&lun->lun_lock);
                if (lun->flags & CTL_LUN_DISABLED) {
                        mtx_unlock(&lun->lun_lock);
                        lun = NULL;
                }
        }
        CTL_LUN(ctsio) = lun;
        if (lun) {
                CTL_BACKEND_LUN(ctsio) = lun->be_lun;

                /*
                 * Every I/O goes into the OOA queue for a particular LUN,
                 * and stays there until completion.
                 */
#ifdef CTL_TIME_IO
                if (TAILQ_EMPTY(&lun->ooa_queue))
                        lun->idle_time += getsbinuptime() - lun->last_busy;
#endif
                TAILQ_INSERT_TAIL(&lun->ooa_queue, &ctsio->io_hdr, ooa_links);
        }

        /* Get command entry and return error if it is unsuppotyed. */
        entry = ctl_validate_command(ctsio);
        if (entry == NULL) {
                if (lun)
                        mtx_unlock(&lun->lun_lock);
                return (retval);
        }

        ctsio->io_hdr.flags &= ~CTL_FLAG_DATA_MASK;
        ctsio->io_hdr.flags |= entry->flags & CTL_FLAG_DATA_MASK;

        /*
         * Check to see whether we can send this command to LUNs that don't
         * exist.  This should pretty much only be the case for inquiry
         * and request sense.  Further checks, below, really require having
         * a LUN, so we can't really check the command anymore.  Just put
         * it on the rtr queue.
         */
        if (lun == NULL) {
                if (entry->flags & CTL_CMD_FLAG_OK_ON_NO_LUN) {
                        ctsio->io_hdr.flags |= CTL_FLAG_IS_WAS_ON_RTR;
                        ctl_enqueue_rtr((union ctl_io *)ctsio);
                        return (retval);
                }

                ctl_set_unsupported_lun(ctsio);
                ctl_done((union ctl_io *)ctsio);
                CTL_DEBUG_PRINT(("ctl_scsiio_precheck: bailing out due to invalid LUN\n"));
                return (retval);
        } else {
                /*
                 * Make sure we support this particular command on this LUN.
                 * e.g., we don't support writes to the control LUN.
                 */
                if (!ctl_cmd_applicable(lun->be_lun->lun_type, entry)) {
                        mtx_unlock(&lun->lun_lock);
                        ctl_set_invalid_opcode(ctsio);
                        ctl_done((union ctl_io *)ctsio);
                        return (retval);
                }
        }

        initidx = ctl_get_initindex(&ctsio->io_hdr.nexus);

        /*
         * If we've got a request sense, it'll clear the contingent
         * allegiance condition.  Otherwise, if we have a CA condition for
         * this initiator, clear it, because it sent down a command other
         * than request sense.
         */
        if (ctsio->cdb[0] != REQUEST_SENSE) {
                struct scsi_sense_data *ps;

                ps = lun->pending_sense[initidx / CTL_MAX_INIT_PER_PORT];
                if (ps != NULL)
                        ps[initidx % CTL_MAX_INIT_PER_PORT].error_code = 0;
        }

        /*
         * If the command has this flag set, it handles its own unit
         * attention reporting, we shouldn't do anything.  Otherwise we
         * check for any pending unit attentions, and send them back to the
         * initiator.  We only do this when a command initially comes in,
         * not when we pull it off the blocked queue.
         *
         * According to SAM-3, section 5.3.2, the order that things get
         * presented back to the host is basically unit attentions caused
         * by some sort of reset event, busy status, reservation conflicts
         * or task set full, and finally any other status.
         *
         * One issue here is that some of the unit attentions we report
         * don't fall into the "reset" category (e.g. "reported luns data
         * has changed").  So reporting it here, before the reservation
         * check, may be technically wrong.  I guess the only thing to do
         * would be to check for and report the reset events here, and then
         * check for the other unit attention types after we check for a
         * reservation conflict.
         *
         * XXX KDM need to fix this
         */
        if ((entry->flags & CTL_CMD_FLAG_NO_SENSE) == 0) {
                ctl_ua_type ua_type;
                u_int sense_len = 0;

                ua_type = ctl_build_ua(lun, initidx, &ctsio->sense_data,
                    &sense_len, SSD_TYPE_NONE);
                if (ua_type != CTL_UA_NONE) {
                        mtx_unlock(&lun->lun_lock);
                        ctsio->scsi_status = SCSI_STATUS_CHECK_COND;
                        ctsio->io_hdr.status = CTL_SCSI_ERROR | CTL_AUTOSENSE;
                        ctsio->sense_len = sense_len;
                        ctl_done((union ctl_io *)ctsio);
                        return (retval);
                }
        }


        if (ctl_scsiio_lun_check(lun, entry, ctsio) != 0) {
                mtx_unlock(&lun->lun_lock);
                ctl_done((union ctl_io *)ctsio);
                return (retval);
        }

        /*
         * XXX CHD this is where we want to send IO to other side if
         * this LUN is secondary on this SC. We will need to make a copy
         * of the IO and flag the IO on this side as SENT_2OTHER and the flag
         * the copy we send as FROM_OTHER.
         * We also need to stuff the address of the original IO so we can
         * find it easily. Something similar will need be done on the other
         * side so when we are done we can find the copy.
         */
        if ((lun->flags & CTL_LUN_PRIMARY_SC) == 0 &&
            (lun->flags & CTL_LUN_PEER_SC_PRIMARY) != 0 &&
            (entry->flags & CTL_CMD_FLAG_RUN_HERE) == 0) {
                union ctl_ha_msg msg_info;
                int isc_retval;

                ctsio->io_hdr.flags |= CTL_FLAG_SENT_2OTHER_SC;
                ctsio->io_hdr.flags &= ~CTL_FLAG_IO_ACTIVE;
                mtx_unlock(&lun->lun_lock);

                msg_info.hdr.msg_type = CTL_MSG_SERIALIZE;
                msg_info.hdr.original_sc = (union ctl_io *)ctsio;
                msg_info.hdr.serializing_sc = NULL;
                msg_info.hdr.nexus = ctsio->io_hdr.nexus;
                msg_info.scsi.tag_num = ctsio->tag_num;
                msg_info.scsi.tag_type = ctsio->tag_type;
                msg_info.scsi.cdb_len = ctsio->cdb_len;
                memcpy(msg_info.scsi.cdb, ctsio->cdb, CTL_MAX_CDBLEN);

                if ((isc_retval = ctl_ha_msg_send(CTL_HA_CHAN_CTL, &msg_info,
                    sizeof(msg_info.scsi) - sizeof(msg_info.scsi.sense_data),
                    M_WAITOK)) > CTL_HA_STATUS_SUCCESS) {
                        ctl_set_busy(ctsio);
                        ctl_done((union ctl_io *)ctsio);
                        return (retval);
                }
                return (retval);
        }

        bio = (union ctl_io *)TAILQ_PREV(&ctsio->io_hdr, ctl_ooaq, ooa_links);
        switch (ctl_check_ooa(lun, (union ctl_io *)ctsio, &bio)) {
        case CTL_ACTION_BLOCK:
                ctsio->io_hdr.blocker = bio;
                TAILQ_INSERT_TAIL(&bio->io_hdr.blocked_queue, &ctsio->io_hdr,
                                  blocked_links);
                mtx_unlock(&lun->lun_lock);
                return (retval);
        case CTL_ACTION_PASS:
        case CTL_ACTION_SKIP:
                ctsio->io_hdr.flags |= CTL_FLAG_IS_WAS_ON_RTR;
                mtx_unlock(&lun->lun_lock);
                ctl_enqueue_rtr((union ctl_io *)ctsio);
                break;
        case CTL_ACTION_OVERLAP:
                mtx_unlock(&lun->lun_lock);
                ctl_set_overlapped_cmd(ctsio);
                ctl_done((union ctl_io *)ctsio);
                break;
        case CTL_ACTION_OVERLAP_TAG:
                mtx_unlock(&lun->lun_lock);
                ctl_set_overlapped_tag(ctsio, ctsio->tag_num & 0xff);
                ctl_done((union ctl_io *)ctsio);
                break;
        case CTL_ACTION_ERROR:
        default:
                mtx_unlock(&lun->lun_lock);
                ctl_set_internal_failure(ctsio,
                                         /*sks_valid*/ 0,
                                         /*retry_count*/ 0);
                ctl_done((union ctl_io *)ctsio);
                break;
        }
        return (retval);
}

const struct ctl_cmd_entry *
ctl_get_cmd_entry(struct ctl_scsiio *ctsio, int *sa)
{
        const struct ctl_cmd_entry *entry;
        int service_action;

        entry = &ctl_cmd_table[ctsio->cdb[0]];
        if (sa)
                *sa = ((entry->flags & CTL_CMD_FLAG_SA5) != 0);
        if (entry->flags & CTL_CMD_FLAG_SA5) {
                service_action = ctsio->cdb[1] & SERVICE_ACTION_MASK;
                entry = &((const struct ctl_cmd_entry *)
                    entry->execute)[service_action];
        }
        return (entry);
}

const struct ctl_cmd_entry *
ctl_validate_command(struct ctl_scsiio *ctsio)
{
        const struct ctl_cmd_entry *entry;
        int i, sa;
        uint8_t diff;

        entry = ctl_get_cmd_entry(ctsio, &sa);
        if (entry->execute == NULL) {
                if (sa)
                        ctl_set_invalid_field(ctsio,
                                              /*sks_valid*/ 1,
                                              /*command*/ 1,
                                              /*field*/ 1,
                                              /*bit_valid*/ 1,
                                              /*bit*/ 4);
                else
                        ctl_set_invalid_opcode(ctsio);
                ctl_done((union ctl_io *)ctsio);
                return (NULL);
        }
        KASSERT(entry->length > 0,
            ("Not defined length for command 0x%02x/0x%02x",
             ctsio->cdb[0], ctsio->cdb[1]));
        for (i = 1; i < entry->length; i++) {
                diff = ctsio->cdb[i] & ~entry->usage[i - 1];
                if (diff == 0)
                        continue;
                ctl_set_invalid_field(ctsio,
                                      /*sks_valid*/ 1,
                                      /*command*/ 1,
                                      /*field*/ i,
                                      /*bit_valid*/ 1,
                                      /*bit*/ fls(diff) - 1);
                ctl_done((union ctl_io *)ctsio);
                return (NULL);
        }
        return (entry);
}

static int
ctl_cmd_applicable(uint8_t lun_type, const struct ctl_cmd_entry *entry)
{

        switch (lun_type) {
        case T_DIRECT:
                if ((entry->flags & CTL_CMD_FLAG_OK_ON_DIRECT) == 0)
                        return (0);
                break;
        case T_PROCESSOR:
                if ((entry->flags & CTL_CMD_FLAG_OK_ON_PROC) == 0)
                        return (0);
                break;
        case T_CDROM:
                if ((entry->flags & CTL_CMD_FLAG_OK_ON_CDROM) == 0)
                        return (0);
                break;
        default:
                return (0);
        }
        return (1);
}

static int
ctl_scsiio(struct ctl_scsiio *ctsio)
{
        int retval;
        const struct ctl_cmd_entry *entry;

        retval = CTL_RETVAL_COMPLETE;

        CTL_DEBUG_PRINT(("ctl_scsiio cdb[0]=%02X\n", ctsio->cdb[0]));

        entry = ctl_get_cmd_entry(ctsio, NULL);

        /*
         * If this I/O has been aborted, just send it straight to
         * ctl_done() without executing it.
         */
        if (ctsio->io_hdr.flags & CTL_FLAG_ABORT) {
                ctl_done((union ctl_io *)ctsio);
                goto bailout;
        }

        /*
         * All the checks should have been handled by ctl_scsiio_precheck().
         * We should be clear now to just execute the I/O.
         */
        retval = entry->execute(ctsio);

bailout:
        return (retval);
}

static int
ctl_target_reset(union ctl_io *io)
{
        struct ctl_softc *softc = CTL_SOFTC(io);
        struct ctl_port *port = CTL_PORT(io);
        struct ctl_lun *lun;
        uint32_t initidx;
        ctl_ua_type ua_type;

        if (!(io->io_hdr.flags & CTL_FLAG_FROM_OTHER_SC)) {
                union ctl_ha_msg msg_info;

                msg_info.hdr.nexus = io->io_hdr.nexus;
                msg_info.task.task_action = io->taskio.task_action;
                msg_info.hdr.msg_type = CTL_MSG_MANAGE_TASKS;
                msg_info.hdr.original_sc = NULL;
                msg_info.hdr.serializing_sc = NULL;
                ctl_ha_msg_send(CTL_HA_CHAN_CTL, &msg_info,
                    sizeof(msg_info.task), M_WAITOK);
        }

        initidx = ctl_get_initindex(&io->io_hdr.nexus);
        if (io->taskio.task_action == CTL_TASK_TARGET_RESET)
                ua_type = CTL_UA_TARG_RESET;
        else
                ua_type = CTL_UA_BUS_RESET;
        mtx_lock(&softc->ctl_lock);
        STAILQ_FOREACH(lun, &softc->lun_list, links) {
                if (port != NULL &&
                    ctl_lun_map_to_port(port, lun->lun) == UINT32_MAX)
                        continue;
                ctl_do_lun_reset(lun, initidx, ua_type);
        }
        mtx_unlock(&softc->ctl_lock);
        io->taskio.task_status = CTL_TASK_FUNCTION_COMPLETE;
        return (0);
}

/*
 * The LUN should always be set.  The I/O is optional, and is used to
 * distinguish between I/Os sent by this initiator, and by other
 * initiators.  We set unit attention for initiators other than this one.
 * SAM-3 is vague on this point.  It does say that a unit attention should
 * be established for other initiators when a LUN is reset (see section
 * 5.7.3), but it doesn't specifically say that the unit attention should
 * be established for this particular initiator when a LUN is reset.  Here
 * is the relevant text, from SAM-3 rev 8:
 *
 * 5.7.2 When a SCSI initiator port aborts its own tasks
 *
 * When a SCSI initiator port causes its own task(s) to be aborted, no
 * notification that the task(s) have been aborted shall be returned to
 * the SCSI initiator port other than the completion response for the
 * command or task management function action that caused the task(s) to
 * be aborted and notification(s) associated with related effects of the
 * action (e.g., a reset unit attention condition).
 *
 * XXX KDM for now, we're setting unit attention for all initiators.
 */
static void
ctl_do_lun_reset(struct ctl_lun *lun, uint32_t initidx, ctl_ua_type ua_type)
{
        union ctl_io *xio;
        int i;

        mtx_lock(&lun->lun_lock);
        /* Abort tasks. */
        for (xio = (union ctl_io *)TAILQ_FIRST(&lun->ooa_queue); xio != NULL;
             xio = (union ctl_io *)TAILQ_NEXT(&xio->io_hdr, ooa_links)) {
                xio->io_hdr.flags |= CTL_FLAG_ABORT | CTL_FLAG_ABORT_STATUS;
                ctl_try_unblock_io(lun, xio, FALSE);
        }
        /* Clear CA. */
        for (i = 0; i < ctl_max_ports; i++) {
                free(lun->pending_sense[i], M_CTL);
                lun->pending_sense[i] = NULL;
        }
        /* Clear reservation. */
        lun->flags &= ~CTL_LUN_RESERVED;
        /* Clear prevent media removal. */
        if (lun->prevent) {
                for (i = 0; i < CTL_MAX_INITIATORS; i++)
                        ctl_clear_mask(lun->prevent, i);
                lun->prevent_count = 0;
        }
        /* Clear TPC status */
        ctl_tpc_lun_clear(lun, -1);
        /* Establish UA. */
#if 0
        ctl_est_ua_all(lun, initidx, ua_type);
#else
        ctl_est_ua_all(lun, -1, ua_type);
#endif
        mtx_unlock(&lun->lun_lock);
}

static int
ctl_lun_reset(union ctl_io *io)
{
        struct ctl_softc *softc = CTL_SOFTC(io);
        struct ctl_lun *lun;
        uint32_t targ_lun, initidx;

        targ_lun = io->io_hdr.nexus.targ_mapped_lun;
        initidx = ctl_get_initindex(&io->io_hdr.nexus);
        mtx_lock(&softc->ctl_lock);
        if (targ_lun >= ctl_max_luns ||
            (lun = softc->ctl_luns[targ_lun]) == NULL) {
                mtx_unlock(&softc->ctl_lock);
                io->taskio.task_status = CTL_TASK_LUN_DOES_NOT_EXIST;
                return (1);
        }
        ctl_do_lun_reset(lun, initidx, CTL_UA_LUN_RESET);
        mtx_unlock(&softc->ctl_lock);
        io->taskio.task_status = CTL_TASK_FUNCTION_COMPLETE;

        if ((io->io_hdr.flags & CTL_FLAG_FROM_OTHER_SC) == 0) {
                union ctl_ha_msg msg_info;

                msg_info.hdr.msg_type = CTL_MSG_MANAGE_TASKS;
                msg_info.hdr.nexus = io->io_hdr.nexus;
                msg_info.task.task_action = CTL_TASK_LUN_RESET;
                msg_info.hdr.original_sc = NULL;
                msg_info.hdr.serializing_sc = NULL;
                ctl_ha_msg_send(CTL_HA_CHAN_CTL, &msg_info,
                    sizeof(msg_info.task), M_WAITOK);
        }
        return (0);
}

static void
ctl_abort_tasks_lun(struct ctl_lun *lun, uint32_t targ_port, uint32_t init_id,
    int other_sc)
{
        union ctl_io *xio;

        mtx_assert(&lun->lun_lock, MA_OWNED);

        /*
         * Run through the OOA queue and attempt to find the given I/O.
         * The target port, initiator ID, tag type and tag number have to
         * match the values that we got from the initiator.  If we have an
         * untagged command to abort, simply abort the first untagged command
         * we come to.  We only allow one untagged command at a time of course.
         */
        for (xio = (union ctl_io *)TAILQ_FIRST(&lun->ooa_queue); xio != NULL;
             xio = (union ctl_io *)TAILQ_NEXT(&xio->io_hdr, ooa_links)) {

                if ((targ_port == UINT32_MAX ||
                     targ_port == xio->io_hdr.nexus.targ_port) &&
                    (init_id == UINT32_MAX ||
                     init_id == xio->io_hdr.nexus.initid)) {
                        if (targ_port != xio->io_hdr.nexus.targ_port ||
                            init_id != xio->io_hdr.nexus.initid)
                                xio->io_hdr.flags |= CTL_FLAG_ABORT_STATUS;
                        xio->io_hdr.flags |= CTL_FLAG_ABORT;
                        if (!other_sc && !(lun->flags & CTL_LUN_PRIMARY_SC)) {
                                union ctl_ha_msg msg_info;

                                msg_info.hdr.nexus = xio->io_hdr.nexus;
                                msg_info.task.task_action = CTL_TASK_ABORT_TASK;
                                msg_info.task.tag_num = xio->scsiio.tag_num;
                                msg_info.task.tag_type = xio->scsiio.tag_type;
                                msg_info.hdr.msg_type = CTL_MSG_MANAGE_TASKS;
                                msg_info.hdr.original_sc = NULL;
                                msg_info.hdr.serializing_sc = NULL;
                                ctl_ha_msg_send(CTL_HA_CHAN_CTL, &msg_info,
                                    sizeof(msg_info.task), M_NOWAIT);
                        }
                        ctl_try_unblock_io(lun, xio, FALSE);
                }
        }
}

static int
ctl_abort_task_set(union ctl_io *io)
{
        struct ctl_softc *softc = CTL_SOFTC(io);
        struct ctl_lun *lun;
        uint32_t targ_lun;

        /*
         * Look up the LUN.
         */
        targ_lun = io->io_hdr.nexus.targ_mapped_lun;
        mtx_lock(&softc->ctl_lock);
        if (targ_lun >= ctl_max_luns ||
            (lun = softc->ctl_luns[targ_lun]) == NULL) {
                mtx_unlock(&softc->ctl_lock);
                io->taskio.task_status = CTL_TASK_LUN_DOES_NOT_EXIST;
                return (1);
        }

        mtx_lock(&lun->lun_lock);
        mtx_unlock(&softc->ctl_lock);
        if (io->taskio.task_action == CTL_TASK_ABORT_TASK_SET) {
                ctl_abort_tasks_lun(lun, io->io_hdr.nexus.targ_port,
                    io->io_hdr.nexus.initid,
                    (io->io_hdr.flags & CTL_FLAG_FROM_OTHER_SC) != 0);
        } else { /* CTL_TASK_CLEAR_TASK_SET */
                ctl_abort_tasks_lun(lun, UINT32_MAX, UINT32_MAX,
                    (io->io_hdr.flags & CTL_FLAG_FROM_OTHER_SC) != 0);
        }
        mtx_unlock(&lun->lun_lock);
        io->taskio.task_status = CTL_TASK_FUNCTION_COMPLETE;
        return (0);
}

static void
ctl_i_t_nexus_loss(struct ctl_softc *softc, uint32_t initidx,
    ctl_ua_type ua_type)
{
        struct ctl_lun *lun;
        struct scsi_sense_data *ps;
        uint32_t p, i;

        p = initidx / CTL_MAX_INIT_PER_PORT;
        i = initidx % CTL_MAX_INIT_PER_PORT;
        mtx_lock(&softc->ctl_lock);
        STAILQ_FOREACH(lun, &softc->lun_list, links) {
                mtx_lock(&lun->lun_lock);
                /* Abort tasks. */
                ctl_abort_tasks_lun(lun, p, i, 1);
                /* Clear CA. */
                ps = lun->pending_sense[p];
                if (ps != NULL)
                        ps[i].error_code = 0;
                /* Clear reservation. */
                if ((lun->flags & CTL_LUN_RESERVED) && (lun->res_idx == initidx))
                        lun->flags &= ~CTL_LUN_RESERVED;
                /* Clear prevent media removal. */
                if (lun->prevent && ctl_is_set(lun->prevent, initidx)) {
                        ctl_clear_mask(lun->prevent, initidx);
                        lun->prevent_count--;
                }
                /* Clear TPC status */
                ctl_tpc_lun_clear(lun, initidx);
                /* Establish UA. */
                ctl_est_ua(lun, initidx, ua_type);
                mtx_unlock(&lun->lun_lock);
        }
        mtx_unlock(&softc->ctl_lock);
}

static int
ctl_i_t_nexus_reset(union ctl_io *io)
{
        struct ctl_softc *softc = CTL_SOFTC(io);
        uint32_t initidx;

        if (!(io->io_hdr.flags & CTL_FLAG_FROM_OTHER_SC)) {
                union ctl_ha_msg msg_info;

                msg_info.hdr.nexus = io->io_hdr.nexus;
                msg_info.task.task_action = CTL_TASK_I_T_NEXUS_RESET;
                msg_info.hdr.msg_type = CTL_MSG_MANAGE_TASKS;
                msg_info.hdr.original_sc = NULL;
                msg_info.hdr.serializing_sc = NULL;
                ctl_ha_msg_send(CTL_HA_CHAN_CTL, &msg_info,
                    sizeof(msg_info.task), M_WAITOK);
        }

        initidx = ctl_get_initindex(&io->io_hdr.nexus);
        ctl_i_t_nexus_loss(softc, initidx, CTL_UA_I_T_NEXUS_LOSS);
        io->taskio.task_status = CTL_TASK_FUNCTION_COMPLETE;
        return (0);
}

static int
ctl_abort_task(union ctl_io *io)
{
        struct ctl_softc *softc = CTL_SOFTC(io);
        union ctl_io *xio;
        struct ctl_lun *lun;
        uint32_t targ_lun;

        /*
         * Look up the LUN.
         */
        targ_lun = io->io_hdr.nexus.targ_mapped_lun;
        mtx_lock(&softc->ctl_lock);
        if (targ_lun >= ctl_max_luns ||
            (lun = softc->ctl_luns[targ_lun]) == NULL) {
                mtx_unlock(&softc->ctl_lock);
                io->taskio.task_status = CTL_TASK_LUN_DOES_NOT_EXIST;
                return (1);
        }

        mtx_lock(&lun->lun_lock);
        mtx_unlock(&softc->ctl_lock);
        /*
         * Run through the OOA queue and attempt to find the given I/O.
         * The target port, initiator ID, tag type and tag number have to
         * match the values that we got from the initiator.  If we have an
         * untagged command to abort, simply abort the first untagged command
         * we come to.  We only allow one untagged command at a time of course.
         */
        for (xio = (union ctl_io *)TAILQ_FIRST(&lun->ooa_queue); xio != NULL;
             xio = (union ctl_io *)TAILQ_NEXT(&xio->io_hdr, ooa_links)) {

                if ((xio->io_hdr.nexus.targ_port != io->io_hdr.nexus.targ_port)
                 || (xio->io_hdr.nexus.initid != io->io_hdr.nexus.initid)
                 || (xio->io_hdr.flags & CTL_FLAG_ABORT))
                        continue;

                /*
                 * If the abort says that the task is untagged, the
                 * task in the queue must be untagged.  Otherwise,
                 * we just check to see whether the tag numbers
                 * match.  This is because the QLogic firmware
                 * doesn't pass back the tag type in an abort
                 * request.
                 */
#if 0
                if (((xio->scsiio.tag_type == CTL_TAG_UNTAGGED)
                  && (io->taskio.tag_type == CTL_TAG_UNTAGGED))
                 || (xio->scsiio.tag_num == io->taskio.tag_num)) {
#else
                /*
                 * XXX KDM we've got problems with FC, because it
                 * doesn't send down a tag type with aborts.  So we
                 * can only really go by the tag number...
                 * This may cause problems with parallel SCSI.
                 * Need to figure that out!!
                 */
                if (xio->scsiio.tag_num == io->taskio.tag_num) {
#endif
                        xio->io_hdr.flags |= CTL_FLAG_ABORT;
                        if ((io->io_hdr.flags & CTL_FLAG_FROM_OTHER_SC) == 0 &&
                            !(lun->flags & CTL_LUN_PRIMARY_SC)) {
                                union ctl_ha_msg msg_info;

                                msg_info.hdr.nexus = io->io_hdr.nexus;
                                msg_info.task.task_action = CTL_TASK_ABORT_TASK;
                                msg_info.task.tag_num = io->taskio.tag_num;
                                msg_info.task.tag_type = io->taskio.tag_type;
                                msg_info.hdr.msg_type = CTL_MSG_MANAGE_TASKS;
                                msg_info.hdr.original_sc = NULL;
                                msg_info.hdr.serializing_sc = NULL;
                                ctl_ha_msg_send(CTL_HA_CHAN_CTL, &msg_info,
                                    sizeof(msg_info.task), M_NOWAIT);
                        }
                        ctl_try_unblock_io(lun, xio, FALSE);
                }
        }
        mtx_unlock(&lun->lun_lock);
        io->taskio.task_status = CTL_TASK_FUNCTION_COMPLETE;
        return (0);
}

static int
ctl_query_task(union ctl_io *io, int task_set)
{
        struct ctl_softc *softc = CTL_SOFTC(io);
        union ctl_io *xio;
        struct ctl_lun *lun;
        int found = 0;
        uint32_t targ_lun;

        targ_lun = io->io_hdr.nexus.targ_mapped_lun;
        mtx_lock(&softc->ctl_lock);
        if (targ_lun >= ctl_max_luns ||
            (lun = softc->ctl_luns[targ_lun]) == NULL) {
                mtx_unlock(&softc->ctl_lock);
                io->taskio.task_status = CTL_TASK_LUN_DOES_NOT_EXIST;
                return (1);
        }
        mtx_lock(&lun->lun_lock);
        mtx_unlock(&softc->ctl_lock);
        for (xio = (union ctl_io *)TAILQ_FIRST(&lun->ooa_queue); xio != NULL;
             xio = (union ctl_io *)TAILQ_NEXT(&xio->io_hdr, ooa_links)) {

                if ((xio->io_hdr.nexus.targ_port != io->io_hdr.nexus.targ_port)
                 || (xio->io_hdr.nexus.initid != io->io_hdr.nexus.initid)
                 || (xio->io_hdr.flags & CTL_FLAG_ABORT))
                        continue;

                if (task_set || xio->scsiio.tag_num == io->taskio.tag_num) {
                        found = 1;
                        break;
                }
        }
        mtx_unlock(&lun->lun_lock);
        if (found)
                io->taskio.task_status = CTL_TASK_FUNCTION_SUCCEEDED;
        else
                io->taskio.task_status = CTL_TASK_FUNCTION_COMPLETE;
        return (0);
}

static int
ctl_query_async_event(union ctl_io *io)
{
        struct ctl_softc *softc = CTL_SOFTC(io);
        struct ctl_lun *lun;
        ctl_ua_type ua;
        uint32_t targ_lun, initidx;

        targ_lun = io->io_hdr.nexus.targ_mapped_lun;
        mtx_lock(&softc->ctl_lock);
        if (targ_lun >= ctl_max_luns ||
            (lun = softc->ctl_luns[targ_lun]) == NULL) {
                mtx_unlock(&softc->ctl_lock);
                io->taskio.task_status = CTL_TASK_LUN_DOES_NOT_EXIST;
                return (1);
        }
        mtx_lock(&lun->lun_lock);
        mtx_unlock(&softc->ctl_lock);
        initidx = ctl_get_initindex(&io->io_hdr.nexus);
        ua = ctl_build_qae(lun, initidx, io->taskio.task_resp);
        mtx_unlock(&lun->lun_lock);
        if (ua != CTL_UA_NONE)
                io->taskio.task_status = CTL_TASK_FUNCTION_SUCCEEDED;
        else
                io->taskio.task_status = CTL_TASK_FUNCTION_COMPLETE;
        return (0);
}

static void
ctl_run_task(union ctl_io *io)
{
        int retval = 1;

        CTL_DEBUG_PRINT(("ctl_run_task\n"));
        KASSERT(io->io_hdr.io_type == CTL_IO_TASK,
            ("ctl_run_task: Unextected io_type %d\n", io->io_hdr.io_type));
        io->taskio.task_status = CTL_TASK_FUNCTION_NOT_SUPPORTED;
        bzero(io->taskio.task_resp, sizeof(io->taskio.task_resp));
        switch (io->taskio.task_action) {
        case CTL_TASK_ABORT_TASK:
                retval = ctl_abort_task(io);
                break;
        case CTL_TASK_ABORT_TASK_SET:
        case CTL_TASK_CLEAR_TASK_SET:
                retval = ctl_abort_task_set(io);
                break;
        case CTL_TASK_CLEAR_ACA:
                break;
        case CTL_TASK_I_T_NEXUS_RESET:
                retval = ctl_i_t_nexus_reset(io);
                break;
        case CTL_TASK_LUN_RESET:
                retval = ctl_lun_reset(io);
                break;
        case CTL_TASK_TARGET_RESET:
        case CTL_TASK_BUS_RESET:
                retval = ctl_target_reset(io);
                break;
        case CTL_TASK_PORT_LOGIN:
                break;
        case CTL_TASK_PORT_LOGOUT:
                break;
        case CTL_TASK_QUERY_TASK:
                retval = ctl_query_task(io, 0);
                break;
        case CTL_TASK_QUERY_TASK_SET:
                retval = ctl_query_task(io, 1);
                break;
        case CTL_TASK_QUERY_ASYNC_EVENT:
                retval = ctl_query_async_event(io);
                break;
        default:
                printf("%s: got unknown task management event %d\n",
                       __func__, io->taskio.task_action);
                break;
        }
        if (retval == 0)
                io->io_hdr.status = CTL_SUCCESS;
        else
                io->io_hdr.status = CTL_ERROR;
        ctl_done(io);
}

/*
 * For HA operation.  Handle commands that come in from the other
 * controller.
 */
static void
ctl_handle_isc(union ctl_io *io)
{
        struct ctl_softc *softc = CTL_SOFTC(io);
        struct ctl_lun *lun;
        const struct ctl_cmd_entry *entry;
        uint32_t targ_lun;

        targ_lun = io->io_hdr.nexus.targ_mapped_lun;
        switch (io->io_hdr.msg_type) {
        case CTL_MSG_SERIALIZE:
                ctl_serialize_other_sc_cmd(&io->scsiio);
                break;
        case CTL_MSG_R2R:               /* Only used in SER_ONLY mode. */
                entry = ctl_get_cmd_entry(&io->scsiio, NULL);
                if (targ_lun >= ctl_max_luns ||
                    (lun = softc->ctl_luns[targ_lun]) == NULL) {
                        ctl_done(io);
                        break;
                }
                mtx_lock(&lun->lun_lock);
                if (ctl_scsiio_lun_check(lun, entry, &io->scsiio) != 0) {
                        mtx_unlock(&lun->lun_lock);
                        ctl_done(io);
                        break;
                }
                io->io_hdr.flags |= CTL_FLAG_IS_WAS_ON_RTR;
                mtx_unlock(&lun->lun_lock);
                ctl_enqueue_rtr(io);
                break;
        case CTL_MSG_FINISH_IO:
                if (softc->ha_mode == CTL_HA_MODE_XFER) {
                        ctl_done(io);
                        break;
                }
                if (targ_lun >= ctl_max_luns ||
                    (lun = softc->ctl_luns[targ_lun]) == NULL) {
                        ctl_free_io(io);
                        break;
                }
                mtx_lock(&lun->lun_lock);
                ctl_try_unblock_others(lun, io, TRUE);
                TAILQ_REMOVE(&lun->ooa_queue, &io->io_hdr, ooa_links);
                mtx_unlock(&lun->lun_lock);
                ctl_free_io(io);
                break;
        case CTL_MSG_PERS_ACTION:
                ctl_hndl_per_res_out_on_other_sc(io);
                ctl_free_io(io);
                break;
        case CTL_MSG_BAD_JUJU:
                ctl_done(io);
                break;
        case CTL_MSG_DATAMOVE:          /* Only used in XFER mode */
                ctl_datamove_remote(io);
                break;
        case CTL_MSG_DATAMOVE_DONE:     /* Only used in XFER mode */
                io->scsiio.be_move_done(io);
                break;
        case CTL_MSG_FAILOVER:
                ctl_failover_lun(io);
                ctl_free_io(io);
                break;
        default:
                printf("%s: Invalid message type %d\n",
                       __func__, io->io_hdr.msg_type);
                ctl_free_io(io);
                break;
        }

}


/*
 * Returns the match type in the case of a match, or CTL_LUN_PAT_NONE if
 * there is no match.
 */
static ctl_lun_error_pattern
ctl_cmd_pattern_match(struct ctl_scsiio *ctsio, struct ctl_error_desc *desc)
{
        const struct ctl_cmd_entry *entry;
        ctl_lun_error_pattern filtered_pattern, pattern;

        pattern = desc->error_pattern;

        /*
         * XXX KDM we need more data passed into this function to match a
         * custom pattern, and we actually need to implement custom pattern
         * matching.
         */
        if (pattern & CTL_LUN_PAT_CMD)
                return (CTL_LUN_PAT_CMD);

        if ((pattern & CTL_LUN_PAT_MASK) == CTL_LUN_PAT_ANY)
                return (CTL_LUN_PAT_ANY);

        entry = ctl_get_cmd_entry(ctsio, NULL);

        filtered_pattern = entry->pattern & pattern;

        /*
         * If the user requested specific flags in the pattern (e.g.
         * CTL_LUN_PAT_RANGE), make sure the command supports all of those
         * flags.
         *
         * If the user did not specify any flags, it doesn't matter whether
         * or not the command supports the flags.
         */
        if ((filtered_pattern & ~CTL_LUN_PAT_MASK) !=
             (pattern & ~CTL_LUN_PAT_MASK))
                return (CTL_LUN_PAT_NONE);

        /*
         * If the user asked for a range check, see if the requested LBA
         * range overlaps with this command's LBA range.
         */
        if (filtered_pattern & CTL_LUN_PAT_RANGE) {
                uint64_t lba1;
                uint64_t len1;
                ctl_action action;
                int retval;

                retval = ctl_get_lba_len((union ctl_io *)ctsio, &lba1, &len1);
                if (retval != 0)
                        return (CTL_LUN_PAT_NONE);

                action = ctl_extent_check_lba(lba1, len1, desc->lba_range.lba,
                                              desc->lba_range.len, FALSE);
                /*
                 * A "pass" means that the LBA ranges don't overlap, so
                 * this doesn't match the user's range criteria.
                 */
                if (action == CTL_ACTION_PASS)
                        return (CTL_LUN_PAT_NONE);
        }

        return (filtered_pattern);
}

static void
ctl_inject_error(struct ctl_lun *lun, union ctl_io *io)
{
        struct ctl_error_desc *desc, *desc2;

        mtx_assert(&lun->lun_lock, MA_OWNED);

        STAILQ_FOREACH_SAFE(desc, &lun->error_list, links, desc2) {
                ctl_lun_error_pattern pattern;
                /*
                 * Check to see whether this particular command matches
                 * the pattern in the descriptor.
                 */
                pattern = ctl_cmd_pattern_match(&io->scsiio, desc);
                if ((pattern & CTL_LUN_PAT_MASK) == CTL_LUN_PAT_NONE)
                        continue;

                switch (desc->lun_error & CTL_LUN_INJ_TYPE) {
                case CTL_LUN_INJ_ABORTED:
                        ctl_set_aborted(&io->scsiio);
                        break;
                case CTL_LUN_INJ_MEDIUM_ERR:
                        ctl_set_medium_error(&io->scsiio,
                            (io->io_hdr.flags & CTL_FLAG_DATA_MASK) !=
                             CTL_FLAG_DATA_OUT);
                        break;
                case CTL_LUN_INJ_UA:
                        /* 29h/00h  POWER ON, RESET, OR BUS DEVICE RESET
                         * OCCURRED */
                        ctl_set_ua(&io->scsiio, 0x29, 0x00);
                        break;
                case CTL_LUN_INJ_CUSTOM:
                        /*
                         * We're assuming the user knows what he is doing.
                         * Just copy the sense information without doing
                         * checks.
                         */
                        bcopy(&desc->custom_sense, &io->scsiio.sense_data,
                              MIN(sizeof(desc->custom_sense),
                                  sizeof(io->scsiio.sense_data)));
                        io->scsiio.scsi_status = SCSI_STATUS_CHECK_COND;
                        io->scsiio.sense_len = SSD_FULL_SIZE;
                        io->io_hdr.status = CTL_SCSI_ERROR | CTL_AUTOSENSE;
                        break;
                case CTL_LUN_INJ_NONE:
                default:
                        /*
                         * If this is an error injection type we don't know
                         * about, clear the continuous flag (if it is set)
                         * so it will get deleted below.
                         */
                        desc->lun_error &= ~CTL_LUN_INJ_CONTINUOUS;
                        break;
                }
                /*
                 * By default, each error injection action is a one-shot
                 */
                if (desc->lun_error & CTL_LUN_INJ_CONTINUOUS)
                        continue;

                STAILQ_REMOVE(&lun->error_list, desc, ctl_error_desc, links);

                free(desc, M_CTL);
        }
}

#ifdef CTL_IO_DELAY
static void
ctl_datamove_timer_wakeup(void *arg)
{
        union ctl_io *io;

        io = (union ctl_io *)arg;

        ctl_datamove(io);
}
#endif /* CTL_IO_DELAY */

void
ctl_datamove(union ctl_io *io)
{
        void (*fe_datamove)(union ctl_io *io);

        mtx_assert(&((struct ctl_softc *)CTL_SOFTC(io))->ctl_lock, MA_NOTOWNED);

        CTL_DEBUG_PRINT(("ctl_datamove\n"));

        /* No data transferred yet.  Frontend must update this when done. */
        io->scsiio.kern_data_resid = io->scsiio.kern_data_len;

#ifdef CTL_TIME_IO
        if ((time_uptime - io->io_hdr.start_time) > ctl_time_io_secs) {
                char str[256];
                char path_str[64];
                struct sbuf sb;

                ctl_scsi_path_string(io, path_str, sizeof(path_str));
                sbuf_new(&sb, str, sizeof(str), SBUF_FIXEDLEN);

                sbuf_cat(&sb, path_str);
                switch (io->io_hdr.io_type) {
                case CTL_IO_SCSI:
                        ctl_scsi_command_string(&io->scsiio, NULL, &sb);
                        sbuf_printf(&sb, "\n");
                        sbuf_cat(&sb, path_str);
                        sbuf_printf(&sb, "Tag: 0x%04x, type %d\n",
                                    io->scsiio.tag_num, io->scsiio.tag_type);
                        break;
                case CTL_IO_TASK:
                        sbuf_printf(&sb, "Task I/O type: %d, Tag: 0x%04x, "
                                    "Tag Type: %d\n", io->taskio.task_action,
                                    io->taskio.tag_num, io->taskio.tag_type);
                        break;
                default:
                        panic("%s: Invalid CTL I/O type %d\n",
                            __func__, io->io_hdr.io_type);
                }
                sbuf_cat(&sb, path_str);
                sbuf_printf(&sb, "ctl_datamove: %jd seconds\n",
                            (intmax_t)time_uptime - io->io_hdr.start_time);
                sbuf_finish(&sb);
                printf("%s", sbuf_data(&sb));
        }
#endif /* CTL_TIME_IO */

#ifdef CTL_IO_DELAY
        if (io->io_hdr.flags & CTL_FLAG_DELAY_DONE) {
                io->io_hdr.flags &= ~CTL_FLAG_DELAY_DONE;
        } else {
                struct ctl_lun *lun;

                lun = CTL_LUN(io);
                if ((lun != NULL)
                 && (lun->delay_info.datamove_delay > 0)) {

                        callout_init(&io->io_hdr.delay_callout, /*mpsafe*/ 1);
                        io->io_hdr.flags |= CTL_FLAG_DELAY_DONE;
                        callout_reset(&io->io_hdr.delay_callout,
                                      lun->delay_info.datamove_delay * hz,
                                      ctl_datamove_timer_wakeup, io);
                        if (lun->delay_info.datamove_type ==
                            CTL_DELAY_TYPE_ONESHOT)
                                lun->delay_info.datamove_delay = 0;
                        return;
                }
        }
#endif

        /*
         * This command has been aborted.  Set the port status, so we fail
         * the data move.
         */
        if (io->io_hdr.flags & CTL_FLAG_ABORT) {
                printf("ctl_datamove: tag 0x%04x on (%u:%u:%u) aborted\n",
                       io->scsiio.tag_num, io->io_hdr.nexus.initid,
                       io->io_hdr.nexus.targ_port,
                       io->io_hdr.nexus.targ_lun);
                io->io_hdr.port_status = 31337;
                /*
                 * Note that the backend, in this case, will get the
                 * callback in its context.  In other cases it may get
                 * called in the frontend's interrupt thread context.
                 */
                io->scsiio.be_move_done(io);
                return;
        }

        /* Don't confuse frontend with zero length data move. */
        if (io->scsiio.kern_data_len == 0) {
                io->scsiio.be_move_done(io);
                return;
        }

        fe_datamove = CTL_PORT(io)->fe_datamove;
        fe_datamove(io);
}

static void
ctl_send_datamove_done(union ctl_io *io, int have_lock)
{
        union ctl_ha_msg msg;
#ifdef CTL_TIME_IO
        struct bintime cur_bt;
#endif

        memset(&msg, 0, sizeof(msg));
        msg.hdr.msg_type = CTL_MSG_DATAMOVE_DONE;
        msg.hdr.original_sc = io;
        msg.hdr.serializing_sc = io->io_hdr.remote_io;
        msg.hdr.nexus = io->io_hdr.nexus;
        msg.hdr.status = io->io_hdr.status;
        msg.scsi.kern_data_resid = io->scsiio.kern_data_resid;
        msg.scsi.tag_num = io->scsiio.tag_num;
        msg.scsi.tag_type = io->scsiio.tag_type;
        msg.scsi.scsi_status = io->scsiio.scsi_status;
        memcpy(&msg.scsi.sense_data, &io->scsiio.sense_data,
               io->scsiio.sense_len);
        msg.scsi.sense_len = io->scsiio.sense_len;
        msg.scsi.port_status = io->io_hdr.port_status;
        io->io_hdr.flags &= ~CTL_FLAG_IO_ACTIVE;
        if (io->io_hdr.flags & CTL_FLAG_FAILOVER) {
                ctl_failover_io(io, /*have_lock*/ have_lock);
                return;
        }
        ctl_ha_msg_send(CTL_HA_CHAN_CTL, &msg,
            sizeof(msg.scsi) - sizeof(msg.scsi.sense_data) +
            msg.scsi.sense_len, M_WAITOK);

#ifdef CTL_TIME_IO
        getbinuptime(&cur_bt);
        bintime_sub(&cur_bt, &io->io_hdr.dma_start_bt);
        bintime_add(&io->io_hdr.dma_bt, &cur_bt);
#endif
        io->io_hdr.num_dmas++;
}

/*
 * The DMA to the remote side is done, now we need to tell the other side
 * we're done so it can continue with its data movement.
 */
static void
ctl_datamove_remote_write_cb(struct ctl_ha_dt_req *rq)
{
        union ctl_io *io;
        uint32_t i;

        io = rq->context;

        if (rq->ret != CTL_HA_STATUS_SUCCESS) {
                printf("%s: ISC DMA write failed with error %d", __func__,
                       rq->ret);
                ctl_set_internal_failure(&io->scsiio,
                                         /*sks_valid*/ 1,
                                         /*retry_count*/ rq->ret);
        }

        ctl_dt_req_free(rq);

        for (i = 0; i < io->scsiio.kern_sg_entries; i++)
                free(CTL_LSGLT(io)[i].addr, M_CTL);
        free(CTL_RSGL(io), M_CTL);
        CTL_RSGL(io) = NULL;
        CTL_LSGL(io) = NULL;

        /*
         * The data is in local and remote memory, so now we need to send
         * status (good or back) back to the other side.
         */
        ctl_send_datamove_done(io, /*have_lock*/ 0);
}

/*
 * We've moved the data from the host/controller into local memory.  Now we
 * need to push it over to the remote controller's memory.
 */
static int
ctl_datamove_remote_dm_write_cb(union ctl_io *io)
{
        int retval;

        retval = ctl_datamove_remote_xfer(io, CTL_HA_DT_CMD_WRITE,
                                          ctl_datamove_remote_write_cb);
        return (retval);
}

static void
ctl_datamove_remote_write(union ctl_io *io)
{
        int retval;
        void (*fe_datamove)(union ctl_io *io);

        /*
         * - Get the data from the host/HBA into local memory.
         * - DMA memory from the local controller to the remote controller.
         * - Send status back to the remote controller.
         */

        retval = ctl_datamove_remote_sgl_setup(io);
        if (retval != 0)
                return;

        /* Switch the pointer over so the FETD knows what to do */
        io->scsiio.kern_data_ptr = (uint8_t *)CTL_LSGL(io);

        /*
         * Use a custom move done callback, since we need to send completion
         * back to the other controller, not to the backend on this side.
         */
        io->scsiio.be_move_done = ctl_datamove_remote_dm_write_cb;

        fe_datamove = CTL_PORT(io)->fe_datamove;
        fe_datamove(io);
}

static int
ctl_datamove_remote_dm_read_cb(union ctl_io *io)
{
        uint32_t i;

        for (i = 0; i < io->scsiio.kern_sg_entries; i++)
                free(CTL_LSGLT(io)[i].addr, M_CTL);
        free(CTL_RSGL(io), M_CTL);
        CTL_RSGL(io) = NULL;
        CTL_LSGL(io) = NULL;

        /*
         * The read is done, now we need to send status (good or bad) back
         * to the other side.
         */
        ctl_send_datamove_done(io, /*have_lock*/ 0);

        return (0);
}

static void
ctl_datamove_remote_read_cb(struct ctl_ha_dt_req *rq)
{
        union ctl_io *io;
        void (*fe_datamove)(union ctl_io *io);

        io = rq->context;

        if (rq->ret != CTL_HA_STATUS_SUCCESS) {
                printf("%s: ISC DMA read failed with error %d\n", __func__,
                       rq->ret);
                ctl_set_internal_failure(&io->scsiio,
                                         /*sks_valid*/ 1,
                                         /*retry_count*/ rq->ret);
        }

        ctl_dt_req_free(rq);

        /* Switch the pointer over so the FETD knows what to do */
        io->scsiio.kern_data_ptr = (uint8_t *)CTL_LSGL(io);

        /*
         * Use a custom move done callback, since we need to send completion
         * back to the other controller, not to the backend on this side.
         */
        io->scsiio.be_move_done = ctl_datamove_remote_dm_read_cb;

        /* XXX KDM add checks like the ones in ctl_datamove? */

        fe_datamove = CTL_PORT(io)->fe_datamove;
        fe_datamove(io);
}

static int
ctl_datamove_remote_sgl_setup(union ctl_io *io)
{
        struct ctl_sg_entry *local_sglist;
        uint32_t len_to_go;
        int retval;
        int i;

        retval = 0;
        local_sglist = CTL_LSGL(io);
        len_to_go = io->scsiio.kern_data_len;

        /*
         * The difficult thing here is that the size of the various
         * S/G segments may be different than the size from the
         * remote controller.  That'll make it harder when DMAing
         * the data back to the other side.
         */
        for (i = 0; len_to_go > 0; i++) {
                local_sglist[i].len = MIN(len_to_go, CTL_HA_DATAMOVE_SEGMENT);
                local_sglist[i].addr =
                    malloc(local_sglist[i].len, M_CTL, M_WAITOK);

                len_to_go -= local_sglist[i].len;
        }
        /*
         * Reset the number of S/G entries accordingly.  The original
         * number of S/G entries is available in rem_sg_entries.
         */
        io->scsiio.kern_sg_entries = i;

        return (retval);
}

static int
ctl_datamove_remote_xfer(union ctl_io *io, unsigned command,
                         ctl_ha_dt_cb callback)
{
        struct ctl_ha_dt_req *rq;
        struct ctl_sg_entry *remote_sglist, *local_sglist;
        uint32_t local_used, remote_used, total_used;
        int i, j, isc_ret;

        rq = ctl_dt_req_alloc();

        /*
         * If we failed to allocate the request, and if the DMA didn't fail
         * anyway, set busy status.  This is just a resource allocation
         * failure.
         */
        if ((rq == NULL)
         && ((io->io_hdr.status & CTL_STATUS_MASK) != CTL_STATUS_NONE &&
             (io->io_hdr.status & CTL_STATUS_MASK) != CTL_SUCCESS))
                ctl_set_busy(&io->scsiio);

        if ((io->io_hdr.status & CTL_STATUS_MASK) != CTL_STATUS_NONE &&
            (io->io_hdr.status & CTL_STATUS_MASK) != CTL_SUCCESS) {

                if (rq != NULL)
                        ctl_dt_req_free(rq);

                /*
                 * The data move failed.  We need to return status back
                 * to the other controller.  No point in trying to DMA
                 * data to the remote controller.
                 */

                ctl_send_datamove_done(io, /*have_lock*/ 0);

                return (1);
        }

        local_sglist = CTL_LSGL(io);
        remote_sglist = CTL_RSGL(io);
        local_used = 0;
        remote_used = 0;
        total_used = 0;

        /*
         * Pull/push the data over the wire from/to the other controller.
         * This takes into account the possibility that the local and
         * remote sglists may not be identical in terms of the size of
         * the elements and the number of elements.
         *
         * One fundamental assumption here is that the length allocated for
         * both the local and remote sglists is identical.  Otherwise, we've
         * essentially got a coding error of some sort.
         */
        isc_ret = CTL_HA_STATUS_SUCCESS;
        for (i = 0, j = 0; total_used < io->scsiio.kern_data_len; ) {
                uint32_t cur_len;
                uint8_t *tmp_ptr;

                rq->command = command;
                rq->context = io;

                /*
                 * Both pointers should be aligned.  But it is possible
                 * that the allocation length is not.  They should both
                 * also have enough slack left over at the end, though,
                 * to round up to the next 8 byte boundary.
                 */
                cur_len = MIN(local_sglist[i].len - local_used,
                              remote_sglist[j].len - remote_used);
                rq->size = cur_len;

                tmp_ptr = (uint8_t *)local_sglist[i].addr;
                tmp_ptr += local_used;

#if 0
                /* Use physical addresses when talking to ISC hardware */
                if ((io->io_hdr.flags & CTL_FLAG_BUS_ADDR) == 0) {
                        /* XXX KDM use busdma */
                        rq->local = vtophys(tmp_ptr);
                } else
                        rq->local = tmp_ptr;
#else
                KASSERT((io->io_hdr.flags & CTL_FLAG_BUS_ADDR) == 0,
                    ("HA does not support BUS_ADDR"));
                rq->local = tmp_ptr;
#endif

                tmp_ptr = (uint8_t *)remote_sglist[j].addr;
                tmp_ptr += remote_used;
                rq->remote = tmp_ptr;

                rq->callback = NULL;

                local_used += cur_len;
                if (local_used >= local_sglist[i].len) {
                        i++;
                        local_used = 0;
                }

                remote_used += cur_len;
                if (remote_used >= remote_sglist[j].len) {
                        j++;
                        remote_used = 0;
                }
                total_used += cur_len;

                if (total_used >= io->scsiio.kern_data_len)
                        rq->callback = callback;

                isc_ret = ctl_dt_single(rq);
                if (isc_ret > CTL_HA_STATUS_SUCCESS)
                        break;
        }
        if (isc_ret != CTL_HA_STATUS_WAIT) {
                rq->ret = isc_ret;
                callback(rq);
        }

        return (0);
}

static void
ctl_datamove_remote_read(union ctl_io *io)
{
        int retval;
        uint32_t i;

        /*
         * This will send an error to the other controller in the case of a
         * failure.
         */
        retval = ctl_datamove_remote_sgl_setup(io);
        if (retval != 0)
                return;

        retval = ctl_datamove_remote_xfer(io, CTL_HA_DT_CMD_READ,
                                          ctl_datamove_remote_read_cb);
        if (retval != 0) {
                /*
                 * Make sure we free memory if there was an error..  The
                 * ctl_datamove_remote_xfer() function will send the
                 * datamove done message, or call the callback with an
                 * error if there is a problem.
                 */
                for (i = 0; i < io->scsiio.kern_sg_entries; i++)
                        free(CTL_LSGLT(io)[i].addr, M_CTL);
                free(CTL_RSGL(io), M_CTL);
                CTL_RSGL(io) = NULL;
                CTL_LSGL(io) = NULL;
        }
}

/*
 * Process a datamove request from the other controller.  This is used for
 * XFER mode only, not SER_ONLY mode.  For writes, we DMA into local memory
 * first.  Once that is complete, the data gets DMAed into the remote
 * controller's memory.  For reads, we DMA from the remote controller's
 * memory into our memory first, and then move it out to the FETD.
 */
static void
ctl_datamove_remote(union ctl_io *io)
{

        mtx_assert(&((struct ctl_softc *)CTL_SOFTC(io))->ctl_lock, MA_NOTOWNED);

        if (io->io_hdr.flags & CTL_FLAG_FAILOVER) {
                ctl_failover_io(io, /*have_lock*/ 0);
                return;
        }

        /*
         * Note that we look for an aborted I/O here, but don't do some of
         * the other checks that ctl_datamove() normally does.
         * We don't need to run the datamove delay code, since that should
         * have been done if need be on the other controller.
         */
        if (io->io_hdr.flags & CTL_FLAG_ABORT) {
                printf("%s: tag 0x%04x on (%u:%u:%u) aborted\n", __func__,
                       io->scsiio.tag_num, io->io_hdr.nexus.initid,
                       io->io_hdr.nexus.targ_port,
                       io->io_hdr.nexus.targ_lun);
                io->io_hdr.port_status = 31338;
                ctl_send_datamove_done(io, /*have_lock*/ 0);
                return;
        }

        if ((io->io_hdr.flags & CTL_FLAG_DATA_MASK) == CTL_FLAG_DATA_OUT)
                ctl_datamove_remote_write(io);
        else if ((io->io_hdr.flags & CTL_FLAG_DATA_MASK) == CTL_FLAG_DATA_IN)
                ctl_datamove_remote_read(io);
        else {
                io->io_hdr.port_status = 31339;
                ctl_send_datamove_done(io, /*have_lock*/ 0);
        }
}

static void
ctl_process_done(union ctl_io *io)
{
        struct ctl_softc *softc = CTL_SOFTC(io);
        struct ctl_port *port = CTL_PORT(io);
        struct ctl_lun *lun = CTL_LUN(io);
        void (*fe_done)(union ctl_io *io);
        union ctl_ha_msg msg;

        CTL_DEBUG_PRINT(("ctl_process_done\n"));
        fe_done = port->fe_done;

#ifdef CTL_TIME_IO
        if ((time_uptime - io->io_hdr.start_time) > ctl_time_io_secs) {
                char str[256];
                char path_str[64];
                struct sbuf sb;

                ctl_scsi_path_string(io, path_str, sizeof(path_str));
                sbuf_new(&sb, str, sizeof(str), SBUF_FIXEDLEN);

                sbuf_cat(&sb, path_str);
                switch (io->io_hdr.io_type) {
                case CTL_IO_SCSI:
                        ctl_scsi_command_string(&io->scsiio, NULL, &sb);
                        sbuf_printf(&sb, "\n");
                        sbuf_cat(&sb, path_str);
                        sbuf_printf(&sb, "Tag: 0x%04x, type %d\n",
                                    io->scsiio.tag_num, io->scsiio.tag_type);
                        break;
                case CTL_IO_TASK:
                        sbuf_printf(&sb, "Task I/O type: %d, Tag: 0x%04x, "
                                    "Tag Type: %d\n", io->taskio.task_action,
                                    io->taskio.tag_num, io->taskio.tag_type);
                        break;
                default:
                        panic("%s: Invalid CTL I/O type %d\n",
                            __func__, io->io_hdr.io_type);
                }
                sbuf_cat(&sb, path_str);
                sbuf_printf(&sb, "ctl_process_done: %jd seconds\n",
                            (intmax_t)time_uptime - io->io_hdr.start_time);
                sbuf_finish(&sb);
                printf("%s", sbuf_data(&sb));
        }
#endif /* CTL_TIME_IO */

        switch (io->io_hdr.io_type) {
        case CTL_IO_SCSI:
                break;
        case CTL_IO_TASK:
                if (ctl_debug & CTL_DEBUG_INFO)
                        ctl_io_error_print(io, NULL);
                fe_done(io);
                return;
        default:
                panic("%s: Invalid CTL I/O type %d\n",
                    __func__, io->io_hdr.io_type);
        }

        if (lun == NULL) {
                CTL_DEBUG_PRINT(("NULL LUN for lun %d\n",
                                 io->io_hdr.nexus.targ_mapped_lun));
                goto bailout;
        }

        mtx_lock(&lun->lun_lock);

        /*
         * Check to see if we have any informational exception and status
         * of this command can be modified to report it in form of either
         * RECOVERED ERROR or NO SENSE, depending on MRIE mode page field.
         */
        if (lun->ie_reported == 0 && lun->ie_asc != 0 &&
            io->io_hdr.status == CTL_SUCCESS &&
            (io->io_hdr.flags & CTL_FLAG_STATUS_SENT) == 0) {
                uint8_t mrie = lun->MODE_IE.mrie;
                uint8_t per = ((lun->MODE_RWER.byte3 & SMS_RWER_PER) ||
                    (lun->MODE_VER.byte3 & SMS_VER_PER));
                if (((mrie == SIEP_MRIE_REC_COND && per) ||
                     mrie == SIEP_MRIE_REC_UNCOND ||
                     mrie == SIEP_MRIE_NO_SENSE) &&
                    (ctl_get_cmd_entry(&io->scsiio, NULL)->flags &
                     CTL_CMD_FLAG_NO_SENSE) == 0) {
                        ctl_set_sense(&io->scsiio,
                              /*current_error*/ 1,
                              /*sense_key*/ (mrie == SIEP_MRIE_NO_SENSE) ?
                                SSD_KEY_NO_SENSE : SSD_KEY_RECOVERED_ERROR,
                              /*asc*/ lun->ie_asc,
                              /*ascq*/ lun->ie_ascq,
                              SSD_ELEM_NONE);
                        lun->ie_reported = 1;
                }
        } else if (lun->ie_reported < 0)
                lun->ie_reported = 0;

        /*
         * Check to see if we have any errors to inject here.  We only
         * inject errors for commands that don't already have errors set.
         */
        if (!STAILQ_EMPTY(&lun->error_list) &&
            ((io->io_hdr.status & CTL_STATUS_MASK) == CTL_SUCCESS) &&
            ((io->io_hdr.flags & CTL_FLAG_STATUS_SENT) == 0))
                ctl_inject_error(lun, io);

        /*
         * XXX KDM how do we treat commands that aren't completed
         * successfully?
         *
         * XXX KDM should we also track I/O latency?
         */
        if ((io->io_hdr.status & CTL_STATUS_MASK) == CTL_SUCCESS &&
            io->io_hdr.io_type == CTL_IO_SCSI) {
                int type;
#ifdef CTL_TIME_IO
                struct bintime bt;

                getbinuptime(&bt);
                bintime_sub(&bt, &io->io_hdr.start_bt);
#endif
                if ((io->io_hdr.flags & CTL_FLAG_DATA_MASK) ==
                    CTL_FLAG_DATA_IN)
                        type = CTL_STATS_READ;
                else if ((io->io_hdr.flags & CTL_FLAG_DATA_MASK) ==
                    CTL_FLAG_DATA_OUT)
                        type = CTL_STATS_WRITE;
                else
                        type = CTL_STATS_NO_IO;

                lun->stats.bytes[type] += io->scsiio.kern_total_len;
                lun->stats.operations[type] ++;
                lun->stats.dmas[type] += io->io_hdr.num_dmas;
#ifdef CTL_TIME_IO
                bintime_add(&lun->stats.dma_time[type], &io->io_hdr.dma_bt);
                bintime_add(&lun->stats.time[type], &bt);
#endif

                mtx_lock(&port->port_lock);
                port->stats.bytes[type] += io->scsiio.kern_total_len;
                port->stats.operations[type] ++;
                port->stats.dmas[type] += io->io_hdr.num_dmas;
#ifdef CTL_TIME_IO
                bintime_add(&port->stats.dma_time[type], &io->io_hdr.dma_bt);
                bintime_add(&port->stats.time[type], &bt);
#endif
                mtx_unlock(&port->port_lock);
        }

        /*
         * Run through the blocked queue of this I/O and see if anything
         * can be unblocked, now that this I/O is done and will be removed.
         * We need to do it before removal to have OOA position to start.
         */
        ctl_try_unblock_others(lun, io, TRUE);

        /*
         * Remove this from the OOA queue.
         */
        TAILQ_REMOVE(&lun->ooa_queue, &io->io_hdr, ooa_links);
#ifdef CTL_TIME_IO
        if (TAILQ_EMPTY(&lun->ooa_queue))
                lun->last_busy = getsbinuptime();
#endif

        /*
         * If the LUN has been invalidated, free it if there is nothing
         * left on its OOA queue.
         */
        if ((lun->flags & CTL_LUN_INVALID)
         && TAILQ_EMPTY(&lun->ooa_queue)) {
                mtx_unlock(&lun->lun_lock);
                ctl_free_lun(lun);
        } else
                mtx_unlock(&lun->lun_lock);

bailout:

        /*
         * If this command has been aborted, make sure we set the status
         * properly.  The FETD is responsible for freeing the I/O and doing
         * whatever it needs to do to clean up its state.
         */
        if (io->io_hdr.flags & CTL_FLAG_ABORT)
                ctl_set_task_aborted(&io->scsiio);

        /*
         * If enabled, print command error status.
         */
        if ((io->io_hdr.status & CTL_STATUS_MASK) != CTL_SUCCESS &&
            (ctl_debug & CTL_DEBUG_INFO) != 0)
                ctl_io_error_print(io, NULL);

        /*
         * Tell the FETD or the other shelf controller we're done with this
         * command.  Note that only SCSI commands get to this point.  Task
         * management commands are completed above.
         */
        if ((softc->ha_mode != CTL_HA_MODE_XFER) &&
            (io->io_hdr.flags & CTL_FLAG_SENT_2OTHER_SC)) {
                memset(&msg, 0, sizeof(msg));
                msg.hdr.msg_type = CTL_MSG_FINISH_IO;
                msg.hdr.serializing_sc = io->io_hdr.remote_io;
                msg.hdr.nexus = io->io_hdr.nexus;
                ctl_ha_msg_send(CTL_HA_CHAN_CTL, &msg,
                    sizeof(msg.scsi) - sizeof(msg.scsi.sense_data),
                    M_WAITOK);
        }

        fe_done(io);
}

/*
 * Front end should call this if it doesn't do autosense.  When the request
 * sense comes back in from the initiator, we'll dequeue this and send it.
 */
int
ctl_queue_sense(union ctl_io *io)
{
        struct ctl_softc *softc = CTL_SOFTC(io);
        struct ctl_port *port = CTL_PORT(io);
        struct ctl_lun *lun;
        struct scsi_sense_data *ps;
        uint32_t initidx, p, targ_lun;

        CTL_DEBUG_PRINT(("ctl_queue_sense\n"));

        targ_lun = ctl_lun_map_from_port(port, io->io_hdr.nexus.targ_lun);

        /*
         * LUN lookup will likely move to the ctl_work_thread() once we
         * have our new queueing infrastructure (that doesn't put things on
         * a per-LUN queue initially).  That is so that we can handle
         * things like an INQUIRY to a LUN that we don't have enabled.  We
         * can't deal with that right now.
         * If we don't have a LUN for this, just toss the sense information.
         */
        mtx_lock(&softc->ctl_lock);
        if (targ_lun >= ctl_max_luns ||
            (lun = softc->ctl_luns[targ_lun]) == NULL) {
                mtx_unlock(&softc->ctl_lock);
                goto bailout;
        }
        mtx_lock(&lun->lun_lock);
        mtx_unlock(&softc->ctl_lock);

        initidx = ctl_get_initindex(&io->io_hdr.nexus);
        p = initidx / CTL_MAX_INIT_PER_PORT;
        if (lun->pending_sense[p] == NULL) {
                lun->pending_sense[p] = malloc(sizeof(*ps) * CTL_MAX_INIT_PER_PORT,
                    M_CTL, M_NOWAIT | M_ZERO);
        }
        if ((ps = lun->pending_sense[p]) != NULL) {
                ps += initidx % CTL_MAX_INIT_PER_PORT;
                memset(ps, 0, sizeof(*ps));
                memcpy(ps, &io->scsiio.sense_data, io->scsiio.sense_len);
        }
        mtx_unlock(&lun->lun_lock);

bailout:
        ctl_free_io(io);
        return (CTL_RETVAL_COMPLETE);
}

/*
 * Primary command inlet from frontend ports.  All SCSI and task I/O
 * requests must go through this function.
 */
int
ctl_queue(union ctl_io *io)
{
        struct ctl_port *port = CTL_PORT(io);

        CTL_DEBUG_PRINT(("ctl_queue cdb[0]=%02X\n", io->scsiio.cdb[0]));

#ifdef CTL_TIME_IO
        io->io_hdr.start_time = time_uptime;
        getbinuptime(&io->io_hdr.start_bt);
#endif /* CTL_TIME_IO */

        /* Map FE-specific LUN ID into global one. */
        io->io_hdr.nexus.targ_mapped_lun =
            ctl_lun_map_from_port(port, io->io_hdr.nexus.targ_lun);

        switch (io->io_hdr.io_type) {
        case CTL_IO_SCSI:
        case CTL_IO_TASK:
                if (ctl_debug & CTL_DEBUG_CDB)
                        ctl_io_print(io);
                ctl_enqueue_incoming(io);
                break;
        default:
                printf("ctl_queue: unknown I/O type %d\n", io->io_hdr.io_type);
                return (EINVAL);
        }

        return (CTL_RETVAL_COMPLETE);
}

#ifdef CTL_IO_DELAY
static void
ctl_done_timer_wakeup(void *arg)
{
        union ctl_io *io;

        io = (union ctl_io *)arg;
        ctl_done(io);
}
#endif /* CTL_IO_DELAY */

void
ctl_serseq_done(union ctl_io *io)
{
        struct ctl_lun *lun = CTL_LUN(io);

        if (lun->be_lun == NULL ||
            lun->be_lun->serseq == CTL_LUN_SERSEQ_OFF)
                return;
        mtx_lock(&lun->lun_lock);
        io->io_hdr.flags |= CTL_FLAG_SERSEQ_DONE;
        ctl_try_unblock_others(lun, io, FALSE);
        mtx_unlock(&lun->lun_lock);
}

void
ctl_done(union ctl_io *io)
{

        /*
         * Enable this to catch duplicate completion issues.
         */
#if 0
        if (io->io_hdr.flags & CTL_FLAG_ALREADY_DONE) {
                printf("%s: type %d msg %d cdb %x iptl: "
                       "%u:%u:%u tag 0x%04x "
                       "flag %#x status %x\n",
                        __func__,
                        io->io_hdr.io_type,
                        io->io_hdr.msg_type,
                        io->scsiio.cdb[0],
                        io->io_hdr.nexus.initid,
                        io->io_hdr.nexus.targ_port,
                        io->io_hdr.nexus.targ_lun,
                        (io->io_hdr.io_type ==
                        CTL_IO_TASK) ?
                        io->taskio.tag_num :
                        io->scsiio.tag_num,
                        io->io_hdr.flags,
                        io->io_hdr.status);
        } else
                io->io_hdr.flags |= CTL_FLAG_ALREADY_DONE;
#endif

        /*
         * This is an internal copy of an I/O, and should not go through
         * the normal done processing logic.
         */
        if (io->io_hdr.flags & CTL_FLAG_INT_COPY)
                return;

#ifdef CTL_IO_DELAY
        if (io->io_hdr.flags & CTL_FLAG_DELAY_DONE) {
                io->io_hdr.flags &= ~CTL_FLAG_DELAY_DONE;
        } else {
                struct ctl_lun *lun = CTL_LUN(io);

                if ((lun != NULL)
                 && (lun->delay_info.done_delay > 0)) {

                        callout_init(&io->io_hdr.delay_callout, /*mpsafe*/ 1);
                        io->io_hdr.flags |= CTL_FLAG_DELAY_DONE;
                        callout_reset(&io->io_hdr.delay_callout,
                                      lun->delay_info.done_delay * hz,
                                      ctl_done_timer_wakeup, io);
                        if (lun->delay_info.done_type == CTL_DELAY_TYPE_ONESHOT)
                                lun->delay_info.done_delay = 0;
                        return;
                }
        }
#endif /* CTL_IO_DELAY */

        ctl_enqueue_done(io);
}

static void
ctl_work_thread(void *arg)
{
        struct ctl_thread *thr = (struct ctl_thread *)arg;
        struct ctl_softc *softc = thr->ctl_softc;
        union ctl_io *io;
        int retval;

        CTL_DEBUG_PRINT(("ctl_work_thread starting\n"));
        thread_lock(curthread);
        sched_prio(curthread, PUSER - 1);
        thread_unlock(curthread);

        while (!softc->shutdown) {
                /*
                 * We handle the queues in this order:
                 * - ISC
                 * - done queue (to free up resources, unblock other commands)
                 * - incoming queue
                 * - RtR queue
                 *
                 * If those queues are empty, we break out of the loop and
                 * go to sleep.
                 */
                mtx_lock(&thr->queue_lock);
                io = (union ctl_io *)STAILQ_FIRST(&thr->isc_queue);
                if (io != NULL) {
                        STAILQ_REMOVE_HEAD(&thr->isc_queue, links);
                        mtx_unlock(&thr->queue_lock);
                        ctl_handle_isc(io);
                        continue;
                }
                io = (union ctl_io *)STAILQ_FIRST(&thr->done_queue);
                if (io != NULL) {
                        STAILQ_REMOVE_HEAD(&thr->done_queue, links);
                        /* clear any blocked commands, call fe_done */
                        mtx_unlock(&thr->queue_lock);
                        ctl_process_done(io);
                        continue;
                }
                io = (union ctl_io *)STAILQ_FIRST(&thr->incoming_queue);
                if (io != NULL) {
                        STAILQ_REMOVE_HEAD(&thr->incoming_queue, links);
                        mtx_unlock(&thr->queue_lock);
                        if (io->io_hdr.io_type == CTL_IO_TASK)
                                ctl_run_task(io);
                        else
                                ctl_scsiio_precheck(softc, &io->scsiio);
                        continue;
                }
                io = (union ctl_io *)STAILQ_FIRST(&thr->rtr_queue);
                if (io != NULL) {
                        STAILQ_REMOVE_HEAD(&thr->rtr_queue, links);
                        mtx_unlock(&thr->queue_lock);
                        retval = ctl_scsiio(&io->scsiio);
                        if (retval != CTL_RETVAL_COMPLETE)
                                CTL_DEBUG_PRINT(("ctl_scsiio failed\n"));
                        continue;
                }

                /* Sleep until we have something to do. */
                mtx_sleep(thr, &thr->queue_lock, PDROP, "-", 0);
        }
        thr->thread = NULL;
        kthread_exit();
}

static void
ctl_thresh_thread(void *arg)
{
        struct ctl_softc *softc = (struct ctl_softc *)arg;
        struct ctl_lun *lun;
        struct ctl_logical_block_provisioning_page *page;
        const char *attr;
        union ctl_ha_msg msg;
        uint64_t thres, val;
        int i, e, set;

        CTL_DEBUG_PRINT(("ctl_thresh_thread starting\n"));
        thread_lock(curthread);
        sched_prio(curthread, PUSER - 1);
        thread_unlock(curthread);

        while (!softc->shutdown) {
                mtx_lock(&softc->ctl_lock);
                STAILQ_FOREACH(lun, &softc->lun_list, links) {
                        if ((lun->flags & CTL_LUN_DISABLED) ||
                            (lun->flags & CTL_LUN_NO_MEDIA) ||
                            lun->backend->lun_attr == NULL)
                                continue;
                        if ((lun->flags & CTL_LUN_PRIMARY_SC) == 0 &&
                            softc->ha_mode == CTL_HA_MODE_XFER)
                                continue;
                        if ((lun->MODE_RWER.byte8 & SMS_RWER_LBPERE) == 0)
                                continue;
                        e = 0;
                        page = &lun->MODE_LBP;
                        for (i = 0; i < CTL_NUM_LBP_THRESH; i++) {
                                if ((page->descr[i].flags & SLBPPD_ENABLED) == 0)
                                        continue;
                                thres = scsi_4btoul(page->descr[i].count);
                                thres <<= CTL_LBP_EXPONENT;
                                switch (page->descr[i].resource) {
                                case 0x01:
                                        attr = "blocksavail";
                                        break;
                                case 0x02:
                                        attr = "blocksused";
                                        break;
                                case 0xf1:
                                        attr = "poolblocksavail";
                                        break;
                                case 0xf2:
                                        attr = "poolblocksused";
                                        break;
                                default:
                                        continue;
                                }
                                mtx_unlock(&softc->ctl_lock); // XXX
                                val = lun->backend->lun_attr(lun->be_lun, attr);
                                mtx_lock(&softc->ctl_lock);
                                if (val == UINT64_MAX)
                                        continue;
                                if ((page->descr[i].flags & SLBPPD_ARMING_MASK)
                                    == SLBPPD_ARMING_INC)
                                        e = (val >= thres);
                                else
                                        e = (val <= thres);
                                if (e)
                                        break;
                        }
                        mtx_lock(&lun->lun_lock);
                        if (e) {
                                scsi_u64to8b((uint8_t *)&page->descr[i] -
                                    (uint8_t *)page, lun->ua_tpt_info);
                                if (lun->lasttpt == 0 ||
                                    time_uptime - lun->lasttpt >= CTL_LBP_UA_PERIOD) {
                                        lun->lasttpt = time_uptime;
                                        ctl_est_ua_all(lun, -1, CTL_UA_THIN_PROV_THRES);
                                        set = 1;
                                } else
                                        set = 0;
                        } else {
                                lun->lasttpt = 0;
                                ctl_clr_ua_all(lun, -1, CTL_UA_THIN_PROV_THRES);
                                set = -1;
                        }
                        mtx_unlock(&lun->lun_lock);
                        if (set != 0 &&
                            lun->ctl_softc->ha_mode == CTL_HA_MODE_XFER) {
                                /* Send msg to other side. */
                                bzero(&msg.ua, sizeof(msg.ua));
                                msg.hdr.msg_type = CTL_MSG_UA;
                                msg.hdr.nexus.initid = -1;
                                msg.hdr.nexus.targ_port = -1;
                                msg.hdr.nexus.targ_lun = lun->lun;
                                msg.hdr.nexus.targ_mapped_lun = lun->lun;
                                msg.ua.ua_all = 1;
                                msg.ua.ua_set = (set > 0);
                                msg.ua.ua_type = CTL_UA_THIN_PROV_THRES;
                                memcpy(msg.ua.ua_info, lun->ua_tpt_info, 8);
                                mtx_unlock(&softc->ctl_lock); // XXX
                                ctl_ha_msg_send(CTL_HA_CHAN_CTL, &msg,
                                    sizeof(msg.ua), M_WAITOK);
                                mtx_lock(&softc->ctl_lock);
                        }
                }
                mtx_sleep(&softc->thresh_thread, &softc->ctl_lock,
                    PDROP, "-", CTL_LBP_PERIOD * hz);
        }
        softc->thresh_thread = NULL;
        kthread_exit();
}

static void
ctl_enqueue_incoming(union ctl_io *io)
{
        struct ctl_softc *softc = CTL_SOFTC(io);
        struct ctl_thread *thr;
        u_int idx;

        idx = (io->io_hdr.nexus.targ_port * 127 +
               io->io_hdr.nexus.initid) % worker_threads;
        thr = &softc->threads[idx];
        mtx_lock(&thr->queue_lock);
        STAILQ_INSERT_TAIL(&thr->incoming_queue, &io->io_hdr, links);
        mtx_unlock(&thr->queue_lock);
        wakeup(thr);
}

static void
ctl_enqueue_rtr(union ctl_io *io)
{
        struct ctl_softc *softc = CTL_SOFTC(io);
        struct ctl_thread *thr;

        thr = &softc->threads[io->io_hdr.nexus.targ_mapped_lun % worker_threads];
        mtx_lock(&thr->queue_lock);
        STAILQ_INSERT_TAIL(&thr->rtr_queue, &io->io_hdr, links);
        mtx_unlock(&thr->queue_lock);
        wakeup(thr);
}

static void
ctl_enqueue_done(union ctl_io *io)
{
        struct ctl_softc *softc = CTL_SOFTC(io);
        struct ctl_thread *thr;

        thr = &softc->threads[io->io_hdr.nexus.targ_mapped_lun % worker_threads];
        mtx_lock(&thr->queue_lock);
        STAILQ_INSERT_TAIL(&thr->done_queue, &io->io_hdr, links);
        mtx_unlock(&thr->queue_lock);
        wakeup(thr);
}

static void
ctl_enqueue_isc(union ctl_io *io)
{
        struct ctl_softc *softc = CTL_SOFTC(io);
        struct ctl_thread *thr;

        thr = &softc->threads[io->io_hdr.nexus.targ_mapped_lun % worker_threads];
        mtx_lock(&thr->queue_lock);
        STAILQ_INSERT_TAIL(&thr->isc_queue, &io->io_hdr, links);
        mtx_unlock(&thr->queue_lock);
        wakeup(thr);
}

/*
 *  vim: ts=8
 */