sys/cam/ctl/ctl_backend_block.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-2-Clause
   3  *
   4  * Copyright (c) 2003 Silicon Graphics International Corp.
   5  * Copyright (c) 2009-2011 Spectra Logic Corporation
   6  * Copyright (c) 2012,2021 The FreeBSD Foundation
   7  * Copyright (c) 2014-2021 Alexander Motin <mav@FreeBSD.org>
   8  * All rights reserved.
   9  *
  10  * Portions of this software were developed by Edward Tomasz Napierala
  11  * under sponsorship from the FreeBSD Foundation.
  12  *
  13  * Portions of this software were developed by Ka Ho Ng <khng@FreeBSD.org>
  14  * under sponsorship from the FreeBSD Foundation.
  15  *
  16  * Redistribution and use in source and binary forms, with or without
  17  * modification, are permitted provided that the following conditions
  18  * are met:
  19  * 1. Redistributions of source code must retain the above copyright
  20  *    notice, this list of conditions, and the following disclaimer,
  21  *    without modification.
  22  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
  23  *    substantially similar to the "NO WARRANTY" disclaimer below
  24  *    ("Disclaimer") and any redistribution must be conditioned upon
  25  *    including a substantially similar Disclaimer requirement for further
  26  *    binary redistribution.
  27  *
  28  * NO WARRANTY
  29  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  30  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  31  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
  32  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  33  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  34  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  35  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  36  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  37  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  38  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  39  * POSSIBILITY OF SUCH DAMAGES.
  40  *
  41  * $Id: //depot/users/kenm/FreeBSD-test2/sys/cam/ctl/ctl_backend_block.c#5 $
  42  */
  43 /*
  44  * CAM Target Layer driver backend for block devices.
  45  *
  46  * Author: Ken Merry <ken@FreeBSD.org>
  47  */
  48 #include <sys/param.h>
  49 #include <sys/systm.h>
  50 #include <sys/kernel.h>
  51 #include <sys/types.h>
  52 #include <sys/kthread.h>
  53 #include <sys/bio.h>
  54 #include <sys/fcntl.h>
  55 #include <sys/limits.h>
  56 #include <sys/lock.h>
  57 #include <sys/mutex.h>
  58 #include <sys/condvar.h>
  59 #include <sys/malloc.h>
  60 #include <sys/conf.h>
  61 #include <sys/ioccom.h>
  62 #include <sys/queue.h>
  63 #include <sys/sbuf.h>
  64 #include <sys/endian.h>
  65 #include <sys/uio.h>
  66 #include <sys/buf.h>
  67 #include <sys/taskqueue.h>
  68 #include <sys/vnode.h>
  69 #include <sys/namei.h>
  70 #include <sys/mount.h>
  71 #include <sys/disk.h>
  72 #include <sys/fcntl.h>
  73 #include <sys/filedesc.h>
  74 #include <sys/filio.h>
  75 #include <sys/proc.h>
  76 #include <sys/pcpu.h>
  77 #include <sys/module.h>
  78 #include <sys/sdt.h>
  79 #include <sys/devicestat.h>
  80 #include <sys/sysctl.h>
  81 #include <sys/nv.h>
  82 #include <sys/dnv.h>
  83 #include <sys/sx.h>
  84 #include <sys/unistd.h>
  85
  86 #include <geom/geom.h>
  87
  88 #include <cam/cam.h>
  89 #include <cam/scsi/scsi_all.h>
  90 #include <cam/scsi/scsi_da.h>
  91 #include <cam/ctl/ctl_io.h>
  92 #include <cam/ctl/ctl.h>
  93 #include <cam/ctl/ctl_backend.h>
  94 #include <cam/ctl/ctl_ioctl.h>
  95 #include <cam/ctl/ctl_ha.h>
  96 #include <cam/ctl/ctl_scsi_all.h>
  97 #include <cam/ctl/ctl_private.h>
  98 #include <cam/ctl/ctl_error.h>
  99
 100 /*
 101  * The idea here is to allocate enough S/G space to handle at least 1MB I/Os.
 102  * On systems with small maxphys it can be 8 128KB segments.  On large systems
 103  * it can be up to 8 1MB segments.  I/Os larger than that we'll split.
 104  */
 105 #define CTLBLK_MAX_SEGS         8
 106 #define CTLBLK_HALF_SEGS        (CTLBLK_MAX_SEGS / 2)
 107 #define CTLBLK_MIN_SEG          (128 * 1024)
 108 #define CTLBLK_MAX_SEG          MIN(1024 * 1024, MAX(CTLBLK_MIN_SEG, maxphys))
 109 #define CTLBLK_MAX_IO_SIZE      (CTLBLK_MAX_SEG * CTLBLK_MAX_SEGS)
 110
 111 #ifdef CTLBLK_DEBUG
 112 #define DPRINTF(fmt, args...) \
 113     printf("cbb(%s:%d): " fmt, __FUNCTION__, __LINE__, ##args)
 114 #else
 115 #define DPRINTF(fmt, args...) do {} while(0)
 116 #endif
 117
 118 #define PRIV(io)        \
 119     ((struct ctl_ptr_len_flags *)&(io)->io_hdr.ctl_private[CTL_PRIV_BACKEND])
 120 #define ARGS(io)        \
 121     ((struct ctl_lba_len_flags *)&(io)->io_hdr.ctl_private[CTL_PRIV_LBA_LEN])
 122
 123 SDT_PROVIDER_DEFINE(cbb);
 124
 125 typedef enum {
 126         CTL_BE_BLOCK_LUN_UNCONFIGURED   = 0x01,
 127         CTL_BE_BLOCK_LUN_WAITING        = 0x04,
 128 } ctl_be_block_lun_flags;
 129
 130 typedef enum {
 131         CTL_BE_BLOCK_NONE,
 132         CTL_BE_BLOCK_DEV,
 133         CTL_BE_BLOCK_FILE
 134 } ctl_be_block_type;
 135
 136 struct ctl_be_block_filedata {
 137         struct ucred *cred;
 138 };
 139
 140 union ctl_be_block_bedata {
 141         struct ctl_be_block_filedata file;
 142 };
 143
 144 struct ctl_be_block_io;
 145 struct ctl_be_block_lun;
 146
 147 typedef void (*cbb_dispatch_t)(struct ctl_be_block_lun *be_lun,
 148                                struct ctl_be_block_io *beio);
 149 typedef uint64_t (*cbb_getattr_t)(struct ctl_be_block_lun *be_lun,
 150                                   const char *attrname);
 151
 152 /*
 153  * Backend LUN structure.  There is a 1:1 mapping between a block device
 154  * and a backend block LUN, and between a backend block LUN and a CTL LUN.
 155  */
 156 struct ctl_be_block_lun {
 157         struct ctl_be_lun cbe_lun;              /* Must be first element. */
 158         struct ctl_lun_create_params params;
 159         char *dev_path;
 160         ctl_be_block_type dev_type;
 161         struct vnode *vn;
 162         union ctl_be_block_bedata backend;
 163         cbb_dispatch_t dispatch;
 164         cbb_dispatch_t lun_flush;
 165         cbb_dispatch_t unmap;
 166         cbb_dispatch_t get_lba_status;
 167         cbb_getattr_t getattr;
 168         uint64_t size_blocks;
 169         uint64_t size_bytes;
 170         struct ctl_be_block_softc *softc;
 171         struct devstat *disk_stats;
 172         ctl_be_block_lun_flags flags;
 173         SLIST_ENTRY(ctl_be_block_lun) links;
 174         struct taskqueue *io_taskqueue;
 175         struct task io_task;
 176         int num_threads;
 177         STAILQ_HEAD(, ctl_io_hdr) input_queue;
 178         STAILQ_HEAD(, ctl_io_hdr) config_read_queue;
 179         STAILQ_HEAD(, ctl_io_hdr) config_write_queue;
 180         STAILQ_HEAD(, ctl_io_hdr) datamove_queue;
 181         struct mtx_padalign io_lock;
 182         struct mtx_padalign queue_lock;
 183 };
 184
 185 /*
 186  * Overall softc structure for the block backend module.
 187  */
 188 struct ctl_be_block_softc {
 189         struct sx                        modify_lock;
 190         struct mtx                       lock;
 191         int                              num_luns;
 192         SLIST_HEAD(, ctl_be_block_lun)   lun_list;
 193         uma_zone_t                       beio_zone;
 194         uma_zone_t                       bufmin_zone;
 195         uma_zone_t                       bufmax_zone;
 196 };
 197
 198 static struct ctl_be_block_softc backend_block_softc;
 199
 200 /*
 201  * Per-I/O information.
 202  */
 203 struct ctl_be_block_io {
 204         union ctl_io                    *io;
 205         struct ctl_sg_entry             sg_segs[CTLBLK_MAX_SEGS];
 206         struct iovec                    xiovecs[CTLBLK_MAX_SEGS];
 207         int                             refcnt;
 208         int                             bio_cmd;
 209         int                             two_sglists;
 210         int                             num_segs;
 211         int                             num_bios_sent;
 212         int                             num_bios_done;
 213         int                             send_complete;
 214         int                             first_error;
 215         uint64_t                        first_error_offset;
 216         struct bintime                  ds_t0;
 217         devstat_tag_type                ds_tag_type;
 218         devstat_trans_flags             ds_trans_type;
 219         uint64_t                        io_len;
 220         uint64_t                        io_offset;
 221         int                             io_arg;
 222         struct ctl_be_block_softc       *softc;
 223         struct ctl_be_block_lun         *lun;
 224         void (*beio_cont)(struct ctl_be_block_io *beio); /* to continue processing */
 225 };
 226
 227 extern struct ctl_softc *control_softc;
 228
 229 static int cbb_num_threads = 32;
 230 SYSCTL_NODE(_kern_cam_ctl, OID_AUTO, block, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
 231             "CAM Target Layer Block Backend");
 232 SYSCTL_INT(_kern_cam_ctl_block, OID_AUTO, num_threads, CTLFLAG_RWTUN,
 233            &cbb_num_threads, 0, "Number of threads per backing file");
 234
 235 static struct ctl_be_block_io *ctl_alloc_beio(struct ctl_be_block_softc *softc);
 236 static void ctl_free_beio(struct ctl_be_block_io *beio);
 237 static void ctl_complete_beio(struct ctl_be_block_io *beio);
 238 static int ctl_be_block_move_done(union ctl_io *io, bool samethr);
 239 static void ctl_be_block_biodone(struct bio *bio);
 240 static void ctl_be_block_flush_file(struct ctl_be_block_lun *be_lun,
 241                                     struct ctl_be_block_io *beio);
 242 static void ctl_be_block_dispatch_file(struct ctl_be_block_lun *be_lun,
 243                                        struct ctl_be_block_io *beio);
 244 static void ctl_be_block_gls_file(struct ctl_be_block_lun *be_lun,
 245                                   struct ctl_be_block_io *beio);
 246 static uint64_t ctl_be_block_getattr_file(struct ctl_be_block_lun *be_lun,
 247                                          const char *attrname);
 248 static void ctl_be_block_unmap_file(struct ctl_be_block_lun *be_lun,
 249                                     struct ctl_be_block_io *beio);
 250 static void ctl_be_block_flush_dev(struct ctl_be_block_lun *be_lun,
 251                                    struct ctl_be_block_io *beio);
 252 static void ctl_be_block_unmap_dev(struct ctl_be_block_lun *be_lun,
 253                                    struct ctl_be_block_io *beio);
 254 static void ctl_be_block_dispatch_dev(struct ctl_be_block_lun *be_lun,
 255                                       struct ctl_be_block_io *beio);
 256 static uint64_t ctl_be_block_getattr_dev(struct ctl_be_block_lun *be_lun,
 257                                          const char *attrname);
 258 static void ctl_be_block_cr_dispatch(struct ctl_be_block_lun *be_lun,
 259                                     union ctl_io *io);
 260 static void ctl_be_block_cw_dispatch(struct ctl_be_block_lun *be_lun,
 261                                     union ctl_io *io);
 262 static void ctl_be_block_dispatch(struct ctl_be_block_lun *be_lun,
 263                                   union ctl_io *io);
 264 static void ctl_be_block_worker(void *context, int pending);
 265 static int ctl_be_block_submit(union ctl_io *io);
 266 static int ctl_be_block_ioctl(struct cdev *dev, u_long cmd, caddr_t addr,
 267                                    int flag, struct thread *td);
 268 static int ctl_be_block_open_file(struct ctl_be_block_lun *be_lun,
 269                                   struct ctl_lun_req *req);
 270 static int ctl_be_block_open_dev(struct ctl_be_block_lun *be_lun,
 271                                  struct ctl_lun_req *req);
 272 static int ctl_be_block_close(struct ctl_be_block_lun *be_lun);
 273 static int ctl_be_block_open(struct ctl_be_block_lun *be_lun,
 274                              struct ctl_lun_req *req);
 275 static int ctl_be_block_create(struct ctl_be_block_softc *softc,
 276                                struct ctl_lun_req *req);
 277 static int ctl_be_block_rm(struct ctl_be_block_softc *softc,
 278                            struct ctl_lun_req *req);
 279 static int ctl_be_block_modify(struct ctl_be_block_softc *softc,
 280                            struct ctl_lun_req *req);
 281 static void ctl_be_block_lun_shutdown(struct ctl_be_lun *cbe_lun);
 282 static int ctl_be_block_config_write(union ctl_io *io);
 283 static int ctl_be_block_config_read(union ctl_io *io);
 284 static int ctl_be_block_lun_info(struct ctl_be_lun *cbe_lun, struct sbuf *sb);
 285 static uint64_t ctl_be_block_lun_attr(struct ctl_be_lun *cbe_lun, const char *attrname);
 286 static int ctl_be_block_init(void);
 287 static int ctl_be_block_shutdown(void);
 288
 289 static struct ctl_backend_driver ctl_be_block_driver =
 290 {
 291         .name = "block",
 292         .flags = CTL_BE_FLAG_HAS_CONFIG,
 293         .init = ctl_be_block_init,
 294         .shutdown = ctl_be_block_shutdown,
 295         .data_submit = ctl_be_block_submit,
 296         .config_read = ctl_be_block_config_read,
 297         .config_write = ctl_be_block_config_write,
 298         .ioctl = ctl_be_block_ioctl,
 299         .lun_info = ctl_be_block_lun_info,
 300         .lun_attr = ctl_be_block_lun_attr
 301 };
 302
 303 MALLOC_DEFINE(M_CTLBLK, "ctlblock", "Memory used for CTL block backend");
 304 CTL_BACKEND_DECLARE(cbb, ctl_be_block_driver);
 305
 306 static void
 307 ctl_alloc_seg(struct ctl_be_block_softc *softc, struct ctl_sg_entry *sg,
 308     size_t len)
 309 {
 310
 311         if (len <= CTLBLK_MIN_SEG) {
 312                 sg->addr = uma_zalloc(softc->bufmin_zone, M_WAITOK);
 313         } else {
 314                 KASSERT(len <= CTLBLK_MAX_SEG,
 315                     ("Too large alloc %zu > %lu", len, CTLBLK_MAX_SEG));
 316                 sg->addr = uma_zalloc(softc->bufmax_zone, M_WAITOK);
 317         }
 318         sg->len = len;
 319 }
 320
 321 static void
 322 ctl_free_seg(struct ctl_be_block_softc *softc, struct ctl_sg_entry *sg)
 323 {
 324
 325         if (sg->len <= CTLBLK_MIN_SEG) {
 326                 uma_zfree(softc->bufmin_zone, sg->addr);
 327         } else {
 328                 KASSERT(sg->len <= CTLBLK_MAX_SEG,
 329                     ("Too large free %zu > %lu", sg->len, CTLBLK_MAX_SEG));
 330                 uma_zfree(softc->bufmax_zone, sg->addr);
 331         }
 332 }
 333
 334 static struct ctl_be_block_io *
 335 ctl_alloc_beio(struct ctl_be_block_softc *softc)
 336 {
 337         struct ctl_be_block_io *beio;
 338
 339         beio = uma_zalloc(softc->beio_zone, M_WAITOK | M_ZERO);
 340         beio->softc = softc;
 341         beio->refcnt = 1;
 342         return (beio);
 343 }
 344
 345 static void
 346 ctl_real_free_beio(struct ctl_be_block_io *beio)
 347 {
 348         struct ctl_be_block_softc *softc = beio->softc;
 349         int i;
 350
 351         for (i = 0; i < beio->num_segs; i++) {
 352                 ctl_free_seg(softc, &beio->sg_segs[i]);
 353
 354                 /* For compare we had two equal S/G lists. */
 355                 if (beio->two_sglists) {
 356                         ctl_free_seg(softc,
 357                             &beio->sg_segs[i + CTLBLK_HALF_SEGS]);
 358                 }
 359         }
 360
 361         uma_zfree(softc->beio_zone, beio);
 362 }
 363
 364 static void
 365 ctl_refcnt_beio(void *arg, int diff)
 366 {
 367         struct ctl_be_block_io *beio = arg;
 368
 369         if (atomic_fetchadd_int(&beio->refcnt, diff) + diff == 0)
 370                 ctl_real_free_beio(beio);
 371 }
 372
 373 static void
 374 ctl_free_beio(struct ctl_be_block_io *beio)
 375 {
 376
 377         ctl_refcnt_beio(beio, -1);
 378 }
 379
 380 static void
 381 ctl_complete_beio(struct ctl_be_block_io *beio)
 382 {
 383         union ctl_io *io = beio->io;
 384
 385         if (beio->beio_cont != NULL) {
 386                 beio->beio_cont(beio);
 387         } else {
 388                 ctl_free_beio(beio);
 389                 ctl_data_submit_done(io);
 390         }
 391 }
 392
 393 static size_t
 394 cmp(uint8_t *a, uint8_t *b, size_t size)
 395 {
 396         size_t i;
 397
 398         for (i = 0; i < size; i++) {
 399                 if (a[i] != b[i])
 400                         break;
 401         }
 402         return (i);
 403 }
 404
 405 static void
 406 ctl_be_block_compare(union ctl_io *io)
 407 {
 408         struct ctl_be_block_io *beio;
 409         uint64_t off, res;
 410         int i;
 411         uint8_t info[8];
 412
 413         beio = (struct ctl_be_block_io *)PRIV(io)->ptr;
 414         off = 0;
 415         for (i = 0; i < beio->num_segs; i++) {
 416                 res = cmp(beio->sg_segs[i].addr,
 417                     beio->sg_segs[i + CTLBLK_HALF_SEGS].addr,
 418                     beio->sg_segs[i].len);
 419                 off += res;
 420                 if (res < beio->sg_segs[i].len)
 421                         break;
 422         }
 423         if (i < beio->num_segs) {
 424                 scsi_u64to8b(off, info);
 425                 ctl_set_sense(&io->scsiio, /*current_error*/ 1,
 426                     /*sense_key*/ SSD_KEY_MISCOMPARE,
 427                     /*asc*/ 0x1D, /*ascq*/ 0x00,
 428                     /*type*/ SSD_ELEM_INFO,
 429                     /*size*/ sizeof(info), /*data*/ &info,
 430                     /*type*/ SSD_ELEM_NONE);
 431         } else
 432                 ctl_set_success(&io->scsiio);
 433 }
 434
 435 static int
 436 ctl_be_block_move_done(union ctl_io *io, bool samethr)
 437 {
 438         struct ctl_be_block_io *beio;
 439         struct ctl_be_block_lun *be_lun;
 440         struct ctl_lba_len_flags *lbalen;
 441
 442         beio = (struct ctl_be_block_io *)PRIV(io)->ptr;
 443
 444         DPRINTF("entered\n");
 445         io->scsiio.kern_rel_offset += io->scsiio.kern_data_len;
 446
 447         /*
 448          * We set status at this point for read and compare commands.
 449          */
 450         if ((io->io_hdr.flags & CTL_FLAG_ABORT) == 0 &&
 451             (io->io_hdr.status & CTL_STATUS_MASK) == CTL_STATUS_NONE) {
 452                 lbalen = ARGS(io);
 453                 if (lbalen->flags & CTL_LLF_READ) {
 454                         ctl_set_success(&io->scsiio);
 455                 } else if (lbalen->flags & CTL_LLF_COMPARE) {
 456                         /* We have two data blocks ready for comparison. */
 457                         ctl_be_block_compare(io);
 458                 }
 459         }
 460
 461         /*
 462          * If this is a read, or a write with errors, it is done.
 463          */
 464         if ((beio->bio_cmd == BIO_READ)
 465          || ((io->io_hdr.flags & CTL_FLAG_ABORT) != 0)
 466          || ((io->io_hdr.status & CTL_STATUS_MASK) != CTL_STATUS_NONE)) {
 467                 ctl_complete_beio(beio);
 468                 return (0);
 469         }
 470
 471         /*
 472          * At this point, we have a write and the DMA completed successfully.
 473          * If we were called synchronously in the original thread then just
 474          * dispatch, otherwise we now have to queue it to the task queue to
 475          * execute the backend I/O.  That is because we do blocking
 476          * memory allocations, and in the file backing case, blocking I/O.
 477          * This move done routine is generally called in the SIM's
 478          * interrupt context, and therefore we cannot block.
 479          */
 480         be_lun = (struct ctl_be_block_lun *)CTL_BACKEND_LUN(io);
 481         if (samethr) {
 482                 be_lun->dispatch(be_lun, beio);
 483         } else {
 484                 mtx_lock(&be_lun->queue_lock);
 485                 STAILQ_INSERT_TAIL(&be_lun->datamove_queue, &io->io_hdr, links);
 486                 mtx_unlock(&be_lun->queue_lock);
 487                 taskqueue_enqueue(be_lun->io_taskqueue, &be_lun->io_task);
 488         }
 489         return (0);
 490 }
 491
 492 static void
 493 ctl_be_block_biodone(struct bio *bio)
 494 {
 495         struct ctl_be_block_io *beio = bio->bio_caller1;
 496         struct ctl_be_block_lun *be_lun = beio->lun;
 497         struct ctl_be_lun *cbe_lun = &be_lun->cbe_lun;
 498         union ctl_io *io;
 499         int error;
 500
 501         io = beio->io;
 502
 503         DPRINTF("entered\n");
 504
 505         error = bio->bio_error;
 506         mtx_lock(&be_lun->io_lock);
 507         if (error != 0 &&
 508             (beio->first_error == 0 ||
 509              bio->bio_offset < beio->first_error_offset)) {
 510                 beio->first_error = error;
 511                 beio->first_error_offset = bio->bio_offset;
 512         }
 513
 514         beio->num_bios_done++;
 515
 516         /*
 517          * XXX KDM will this cause WITNESS to complain?  Holding a lock
 518          * during the free might cause it to complain.
 519          */
 520         g_destroy_bio(bio);
 521
 522         /*
 523          * If the send complete bit isn't set, or we aren't the last I/O to
 524          * complete, then we're done.
 525          */
 526         if ((beio->send_complete == 0)
 527          || (beio->num_bios_done < beio->num_bios_sent)) {
 528                 mtx_unlock(&be_lun->io_lock);
 529                 return;
 530         }
 531
 532         /*
 533          * At this point, we've verified that we are the last I/O to
 534          * complete, so it's safe to drop the lock.
 535          */
 536         devstat_end_transaction(beio->lun->disk_stats, beio->io_len,
 537             beio->ds_tag_type, beio->ds_trans_type,
 538             /*now*/ NULL, /*then*/&beio->ds_t0);
 539         mtx_unlock(&be_lun->io_lock);
 540
 541         /*
 542          * If there are any errors from the backing device, we fail the
 543          * entire I/O with a medium error.
 544          */
 545         error = beio->first_error;
 546         if (error != 0) {
 547                 if (error == EOPNOTSUPP) {
 548                         ctl_set_invalid_opcode(&io->scsiio);
 549                 } else if (error == ENOSPC || error == EDQUOT) {
 550                         ctl_set_space_alloc_fail(&io->scsiio);
 551                 } else if (error == EROFS || error == EACCES) {
 552                         ctl_set_hw_write_protected(&io->scsiio);
 553                 } else if (beio->bio_cmd == BIO_FLUSH) {
 554                         /* XXX KDM is there is a better error here? */
 555                         ctl_set_internal_failure(&io->scsiio,
 556                                                  /*sks_valid*/ 1,
 557                                                  /*retry_count*/ 0xbad2);
 558                 } else {
 559                         ctl_set_medium_error(&io->scsiio,
 560                             beio->bio_cmd == BIO_READ);
 561                 }
 562                 ctl_complete_beio(beio);
 563                 return;
 564         }
 565
 566         /*
 567          * If this is a write, a flush, a delete or verify, we're all done.
 568          * If this is a read, we can now send the data to the user.
 569          */
 570         if ((beio->bio_cmd == BIO_WRITE)
 571          || (beio->bio_cmd == BIO_FLUSH)
 572          || (beio->bio_cmd == BIO_DELETE)
 573          || (ARGS(io)->flags & CTL_LLF_VERIFY)) {
 574                 ctl_set_success(&io->scsiio);
 575                 ctl_complete_beio(beio);
 576         } else {
 577                 if ((ARGS(io)->flags & CTL_LLF_READ) &&
 578                     beio->beio_cont == NULL) {
 579                         ctl_set_success(&io->scsiio);
 580                         if (cbe_lun->serseq >= CTL_LUN_SERSEQ_SOFT)
 581                                 ctl_serseq_done(io);
 582                 }
 583                 ctl_datamove(io);
 584         }
 585 }
 586
 587 static void
 588 ctl_be_block_flush_file(struct ctl_be_block_lun *be_lun,
 589                         struct ctl_be_block_io *beio)
 590 {
 591         union ctl_io *io = beio->io;
 592         struct mount *mountpoint;
 593         int error;
 594
 595         DPRINTF("entered\n");
 596
 597         binuptime(&beio->ds_t0);
 598         devstat_start_transaction(beio->lun->disk_stats, &beio->ds_t0);
 599
 600         (void) vn_start_write(be_lun->vn, &mountpoint, V_WAIT);
 601
 602         vn_lock(be_lun->vn, vn_lktype_write(mountpoint, be_lun->vn) |
 603             LK_RETRY);
 604         error = VOP_FSYNC(be_lun->vn, beio->io_arg ? MNT_NOWAIT : MNT_WAIT,
 605             curthread);
 606         VOP_UNLOCK(be_lun->vn);
 607
 608         vn_finished_write(mountpoint);
 609
 610         mtx_lock(&be_lun->io_lock);
 611         devstat_end_transaction(beio->lun->disk_stats, beio->io_len,
 612             beio->ds_tag_type, beio->ds_trans_type,
 613             /*now*/ NULL, /*then*/&beio->ds_t0);
 614         mtx_unlock(&be_lun->io_lock);
 615
 616         if (error == 0)
 617                 ctl_set_success(&io->scsiio);
 618         else {
 619                 /* XXX KDM is there is a better error here? */
 620                 ctl_set_internal_failure(&io->scsiio,
 621                                          /*sks_valid*/ 1,
 622                                          /*retry_count*/ 0xbad1);
 623         }
 624
 625         ctl_complete_beio(beio);
 626 }
 627
 628 SDT_PROBE_DEFINE1(cbb, , read, file_start, "uint64_t");
 629 SDT_PROBE_DEFINE1(cbb, , write, file_start, "uint64_t");
 630 SDT_PROBE_DEFINE1(cbb, , read, file_done,"uint64_t");
 631 SDT_PROBE_DEFINE1(cbb, , write, file_done, "uint64_t");
 632
 633 static void
 634 ctl_be_block_dispatch_file(struct ctl_be_block_lun *be_lun,
 635                            struct ctl_be_block_io *beio)
 636 {
 637         struct ctl_be_lun *cbe_lun = &be_lun->cbe_lun;
 638         struct ctl_be_block_filedata *file_data;
 639         union ctl_io *io;
 640         struct uio xuio;
 641         struct iovec *xiovec;
 642         size_t s;
 643         int error, flags, i;
 644
 645         DPRINTF("entered\n");
 646
 647         file_data = &be_lun->backend.file;
 648         io = beio->io;
 649         flags = 0;
 650         if (ARGS(io)->flags & CTL_LLF_DPO)
 651                 flags |= IO_DIRECT;
 652         if (beio->bio_cmd == BIO_WRITE && ARGS(io)->flags & CTL_LLF_FUA)
 653                 flags |= IO_SYNC;
 654
 655         bzero(&xuio, sizeof(xuio));
 656         if (beio->bio_cmd == BIO_READ) {
 657                 SDT_PROBE0(cbb, , read, file_start);
 658                 xuio.uio_rw = UIO_READ;
 659         } else {
 660                 SDT_PROBE0(cbb, , write, file_start);
 661                 xuio.uio_rw = UIO_WRITE;
 662         }
 663         xuio.uio_offset = beio->io_offset;
 664         xuio.uio_resid = beio->io_len;
 665         xuio.uio_segflg = UIO_SYSSPACE;
 666         xuio.uio_iov = beio->xiovecs;
 667         xuio.uio_iovcnt = beio->num_segs;
 668         xuio.uio_td = curthread;
 669
 670         for (i = 0, xiovec = xuio.uio_iov; i < xuio.uio_iovcnt; i++, xiovec++) {
 671                 xiovec->iov_base = beio->sg_segs[i].addr;
 672                 xiovec->iov_len = beio->sg_segs[i].len;
 673         }
 674
 675         binuptime(&beio->ds_t0);
 676         devstat_start_transaction(beio->lun->disk_stats, &beio->ds_t0);
 677
 678         if (beio->bio_cmd == BIO_READ) {
 679                 vn_lock(be_lun->vn, LK_SHARED | LK_RETRY);
 680
 681                 if (beio->beio_cont == NULL &&
 682                     cbe_lun->serseq == CTL_LUN_SERSEQ_SOFT)
 683                         ctl_serseq_done(io);
 684                 /*
 685                  * UFS pays attention to IO_DIRECT for reads.  If the
 686                  * DIRECTIO option is configured into the kernel, it calls
 687                  * ffs_rawread().  But that only works for single-segment
 688                  * uios with user space addresses.  In our case, with a
 689                  * kernel uio, it still reads into the buffer cache, but it
 690                  * will just try to release the buffer from the cache later
 691                  * on in ffs_read().
 692                  *
 693                  * ZFS does not pay attention to IO_DIRECT for reads.
 694                  *
 695                  * UFS does not pay attention to IO_SYNC for reads.
 696                  *
 697                  * ZFS pays attention to IO_SYNC (which translates into the
 698                  * Solaris define FRSYNC for zfs_read()) for reads.  It
 699                  * attempts to sync the file before reading.
 700                  */
 701                 error = VOP_READ(be_lun->vn, &xuio, flags, file_data->cred);
 702
 703                 VOP_UNLOCK(be_lun->vn);
 704                 SDT_PROBE0(cbb, , read, file_done);
 705                 if (error == 0 && xuio.uio_resid > 0) {
 706                         /*
 707                          * If we red less then requested (EOF), then
 708                          * we should clean the rest of the buffer.
 709                          */
 710                         s = beio->io_len - xuio.uio_resid;
 711                         for (i = 0; i < beio->num_segs; i++) {
 712                                 if (s >= beio->sg_segs[i].len) {
 713                                         s -= beio->sg_segs[i].len;
 714                                         continue;
 715                                 }
 716                                 bzero((uint8_t *)beio->sg_segs[i].addr + s,
 717                                     beio->sg_segs[i].len - s);
 718                                 s = 0;
 719                         }
 720                 }
 721         } else {
 722                 struct mount *mountpoint;
 723
 724                 (void)vn_start_write(be_lun->vn, &mountpoint, V_WAIT);
 725                 vn_lock(be_lun->vn, vn_lktype_write(mountpoint,
 726                     be_lun->vn) | LK_RETRY);
 727
 728                 /*
 729                  * UFS pays attention to IO_DIRECT for writes.  The write
 730                  * is done asynchronously.  (Normally the write would just
 731                  * get put into cache.
 732                  *
 733                  * UFS pays attention to IO_SYNC for writes.  It will
 734                  * attempt to write the buffer out synchronously if that
 735                  * flag is set.
 736                  *
 737                  * ZFS does not pay attention to IO_DIRECT for writes.
 738                  *
 739                  * ZFS pays attention to IO_SYNC (a.k.a. FSYNC or FRSYNC)
 740                  * for writes.  It will flush the transaction from the
 741                  * cache before returning.
 742                  */
 743                 error = VOP_WRITE(be_lun->vn, &xuio, flags, file_data->cred);
 744                 VOP_UNLOCK(be_lun->vn);
 745
 746                 vn_finished_write(mountpoint);
 747                 SDT_PROBE0(cbb, , write, file_done);
 748         }
 749
 750         mtx_lock(&be_lun->io_lock);
 751         devstat_end_transaction(beio->lun->disk_stats, beio->io_len,
 752             beio->ds_tag_type, beio->ds_trans_type,
 753             /*now*/ NULL, /*then*/&beio->ds_t0);
 754         mtx_unlock(&be_lun->io_lock);
 755
 756         /*
 757          * If we got an error, set the sense data to "MEDIUM ERROR" and
 758          * return the I/O to the user.
 759          */
 760         if (error != 0) {
 761                 if (error == ENOSPC || error == EDQUOT) {
 762                         ctl_set_space_alloc_fail(&io->scsiio);
 763                 } else if (error == EROFS || error == EACCES) {
 764                         ctl_set_hw_write_protected(&io->scsiio);
 765                 } else {
 766                         ctl_set_medium_error(&io->scsiio,
 767                             beio->bio_cmd == BIO_READ);
 768                 }
 769                 ctl_complete_beio(beio);
 770                 return;
 771         }
 772
 773         /*
 774          * If this is a write or a verify, we're all done.
 775          * If this is a read, we can now send the data to the user.
 776          */
 777         if ((beio->bio_cmd == BIO_WRITE) ||
 778             (ARGS(io)->flags & CTL_LLF_VERIFY)) {
 779                 ctl_set_success(&io->scsiio);
 780                 ctl_complete_beio(beio);
 781         } else {
 782                 if ((ARGS(io)->flags & CTL_LLF_READ) &&
 783                     beio->beio_cont == NULL) {
 784                         ctl_set_success(&io->scsiio);
 785                         if (cbe_lun->serseq > CTL_LUN_SERSEQ_SOFT)
 786                                 ctl_serseq_done(io);
 787                 }
 788                 ctl_datamove(io);
 789         }
 790 }
 791
 792 static void
 793 ctl_be_block_gls_file(struct ctl_be_block_lun *be_lun,
 794                         struct ctl_be_block_io *beio)
 795 {
 796         union ctl_io *io = beio->io;
 797         struct ctl_lba_len_flags *lbalen = ARGS(io);
 798         struct scsi_get_lba_status_data *data;
 799         off_t roff, off;
 800         int error, status;
 801
 802         DPRINTF("entered\n");
 803
 804         off = roff = ((off_t)lbalen->lba) * be_lun->cbe_lun.blocksize;
 805         vn_lock(be_lun->vn, LK_SHARED | LK_RETRY);
 806         error = VOP_IOCTL(be_lun->vn, FIOSEEKHOLE, &off,
 807             0, curthread->td_ucred, curthread);
 808         if (error == 0 && off > roff)
 809                 status = 0;     /* mapped up to off */
 810         else {
 811                 error = VOP_IOCTL(be_lun->vn, FIOSEEKDATA, &off,
 812                     0, curthread->td_ucred, curthread);
 813                 if (error == 0 && off > roff)
 814                         status = 1;     /* deallocated up to off */
 815                 else {
 816                         status = 0;     /* unknown up to the end */
 817                         off = be_lun->size_bytes;
 818                 }
 819         }
 820         VOP_UNLOCK(be_lun->vn);
 821
 822         data = (struct scsi_get_lba_status_data *)io->scsiio.kern_data_ptr;
 823         scsi_u64to8b(lbalen->lba, data->descr[0].addr);
 824         scsi_ulto4b(MIN(UINT32_MAX, off / be_lun->cbe_lun.blocksize -
 825             lbalen->lba), data->descr[0].length);
 826         data->descr[0].status = status;
 827
 828         ctl_complete_beio(beio);
 829 }
 830
 831 static uint64_t
 832 ctl_be_block_getattr_file(struct ctl_be_block_lun *be_lun, const char *attrname)
 833 {
 834         struct vattr            vattr;
 835         struct statfs           statfs;
 836         uint64_t                val;
 837         int                     error;
 838
 839         val = UINT64_MAX;
 840         if (be_lun->vn == NULL)
 841                 return (val);
 842         vn_lock(be_lun->vn, LK_SHARED | LK_RETRY);
 843         if (strcmp(attrname, "blocksused") == 0) {
 844                 error = VOP_GETATTR(be_lun->vn, &vattr, curthread->td_ucred);
 845                 if (error == 0)
 846                         val = vattr.va_bytes / be_lun->cbe_lun.blocksize;
 847         }
 848         if (strcmp(attrname, "blocksavail") == 0 &&
 849             !VN_IS_DOOMED(be_lun->vn)) {
 850                 error = VFS_STATFS(be_lun->vn->v_mount, &statfs);
 851                 if (error == 0)
 852                         val = statfs.f_bavail * statfs.f_bsize /
 853                             be_lun->cbe_lun.blocksize;
 854         }
 855         VOP_UNLOCK(be_lun->vn);
 856         return (val);
 857 }
 858
 859 static void
 860 ctl_be_block_unmap_file(struct ctl_be_block_lun *be_lun,
 861                         struct ctl_be_block_io *beio)
 862 {
 863         struct ctl_be_block_filedata *file_data;
 864         union ctl_io *io;
 865         struct ctl_ptr_len_flags *ptrlen;
 866         struct scsi_unmap_desc *buf, *end;
 867         struct mount *mp;
 868         off_t off, len;
 869         int error;
 870
 871         io = beio->io;
 872         file_data = &be_lun->backend.file;
 873         mp = NULL;
 874         error = 0;
 875
 876         binuptime(&beio->ds_t0);
 877         devstat_start_transaction(be_lun->disk_stats, &beio->ds_t0);
 878
 879         (void)vn_start_write(be_lun->vn, &mp, V_WAIT);
 880         vn_lock(be_lun->vn, vn_lktype_write(mp, be_lun->vn) | LK_RETRY);
 881         if (beio->io_offset == -1) {
 882                 beio->io_len = 0;
 883                 ptrlen = (struct ctl_ptr_len_flags *)
 884                     &io->io_hdr.ctl_private[CTL_PRIV_LBA_LEN];
 885                 buf = (struct scsi_unmap_desc *)ptrlen->ptr;
 886                 end = buf + ptrlen->len / sizeof(*buf);
 887                 for (; buf < end; buf++) {
 888                         off = (off_t)scsi_8btou64(buf->lba) *
 889                             be_lun->cbe_lun.blocksize;
 890                         len = (off_t)scsi_4btoul(buf->length) *
 891                             be_lun->cbe_lun.blocksize;
 892                         beio->io_len += len;
 893                         error = vn_deallocate(be_lun->vn, &off, &len,
 894                             0, IO_NOMACCHECK | IO_NODELOCKED, file_data->cred,
 895                             NOCRED);
 896                         if (error != 0)
 897                                 break;
 898                 }
 899         } else {
 900                 /* WRITE_SAME */
 901                 off = beio->io_offset;
 902                 len = beio->io_len;
 903                 error = vn_deallocate(be_lun->vn, &off, &len, 0,
 904                     IO_NOMACCHECK | IO_NODELOCKED, file_data->cred, NOCRED);
 905         }
 906         VOP_UNLOCK(be_lun->vn);
 907         vn_finished_write(mp);
 908
 909         mtx_lock(&be_lun->io_lock);
 910         devstat_end_transaction(beio->lun->disk_stats, beio->io_len,
 911             beio->ds_tag_type, beio->ds_trans_type,
 912             /*now*/ NULL, /*then*/&beio->ds_t0);
 913         mtx_unlock(&be_lun->io_lock);
 914
 915         /*
 916          * If we got an error, set the sense data to "MEDIUM ERROR" and
 917          * return the I/O to the user.
 918          */
 919         switch (error) {
 920         case 0:
 921                 ctl_set_success(&io->scsiio);
 922                 break;
 923         case ENOSPC:
 924         case EDQUOT:
 925                 ctl_set_space_alloc_fail(&io->scsiio);
 926                 break;
 927         case EROFS:
 928         case EACCES:
 929                 ctl_set_hw_write_protected(&io->scsiio);
 930                 break;
 931         default:
 932                 ctl_set_medium_error(&io->scsiio, false);
 933         }
 934         ctl_complete_beio(beio);
 935 }
 936
 937 static void
 938 ctl_be_block_dispatch_zvol(struct ctl_be_block_lun *be_lun,
 939                            struct ctl_be_block_io *beio)
 940 {
 941         struct ctl_be_lun *cbe_lun = &be_lun->cbe_lun;
 942         union ctl_io *io;
 943         struct cdevsw *csw;
 944         struct cdev *dev;
 945         struct uio xuio;
 946         struct iovec *xiovec;
 947         int error, flags, i, ref;
 948
 949         DPRINTF("entered\n");
 950
 951         io = beio->io;
 952         flags = 0;
 953         if (ARGS(io)->flags & CTL_LLF_DPO)
 954                 flags |= IO_DIRECT;
 955         if (beio->bio_cmd == BIO_WRITE && ARGS(io)->flags & CTL_LLF_FUA)
 956                 flags |= IO_SYNC;
 957
 958         bzero(&xuio, sizeof(xuio));
 959         if (beio->bio_cmd == BIO_READ) {
 960                 SDT_PROBE0(cbb, , read, file_start);
 961                 xuio.uio_rw = UIO_READ;
 962         } else {
 963                 SDT_PROBE0(cbb, , write, file_start);
 964                 xuio.uio_rw = UIO_WRITE;
 965         }
 966         xuio.uio_offset = beio->io_offset;
 967         xuio.uio_resid = beio->io_len;
 968         xuio.uio_segflg = UIO_SYSSPACE;
 969         xuio.uio_iov = beio->xiovecs;
 970         xuio.uio_iovcnt = beio->num_segs;
 971         xuio.uio_td = curthread;
 972
 973         for (i = 0, xiovec = xuio.uio_iov; i < xuio.uio_iovcnt; i++, xiovec++) {
 974                 xiovec->iov_base = beio->sg_segs[i].addr;
 975                 xiovec->iov_len = beio->sg_segs[i].len;
 976         }
 977
 978         binuptime(&beio->ds_t0);
 979         devstat_start_transaction(beio->lun->disk_stats, &beio->ds_t0);
 980
 981         csw = devvn_refthread(be_lun->vn, &dev, &ref);
 982         if (csw) {
 983                 if (beio->bio_cmd == BIO_READ) {
 984                         if (beio->beio_cont == NULL &&
 985                             cbe_lun->serseq == CTL_LUN_SERSEQ_SOFT)
 986                                 ctl_serseq_done(io);
 987                         error = csw->d_read(dev, &xuio, flags);
 988                 } else
 989                         error = csw->d_write(dev, &xuio, flags);
 990                 dev_relthread(dev, ref);
 991         } else
 992                 error = ENXIO;
 993
 994         if (beio->bio_cmd == BIO_READ)
 995                 SDT_PROBE0(cbb, , read, file_done);
 996         else
 997                 SDT_PROBE0(cbb, , write, file_done);
 998
 999         mtx_lock(&be_lun->io_lock);
1000         devstat_end_transaction(beio->lun->disk_stats, beio->io_len,
1001             beio->ds_tag_type, beio->ds_trans_type,
1002             /*now*/ NULL, /*then*/&beio->ds_t0);
1003         mtx_unlock(&be_lun->io_lock);
1004
1005         /*
1006          * If we got an error, set the sense data to "MEDIUM ERROR" and
1007          * return the I/O to the user.
1008          */
1009         if (error != 0) {
1010                 if (error == ENOSPC || error == EDQUOT) {
1011                         ctl_set_space_alloc_fail(&io->scsiio);
1012                 } else if (error == EROFS || error == EACCES) {
1013                         ctl_set_hw_write_protected(&io->scsiio);
1014                 } else {
1015                         ctl_set_medium_error(&io->scsiio,
1016                             beio->bio_cmd == BIO_READ);
1017                 }
1018                 ctl_complete_beio(beio);
1019                 return;
1020         }
1021
1022         /*
1023          * If this is a write or a verify, we're all done.
1024          * If this is a read, we can now send the data to the user.
1025          */
1026         if ((beio->bio_cmd == BIO_WRITE) ||
1027             (ARGS(io)->flags & CTL_LLF_VERIFY)) {
1028                 ctl_set_success(&io->scsiio);
1029                 ctl_complete_beio(beio);
1030         } else {
1031                 if ((ARGS(io)->flags & CTL_LLF_READ) &&
1032                     beio->beio_cont == NULL) {
1033                         ctl_set_success(&io->scsiio);
1034                         if (cbe_lun->serseq > CTL_LUN_SERSEQ_SOFT)
1035                                 ctl_serseq_done(io);
1036                 }
1037                 ctl_datamove(io);
1038         }
1039 }
1040
1041 static void
1042 ctl_be_block_gls_zvol(struct ctl_be_block_lun *be_lun,
1043                         struct ctl_be_block_io *beio)
1044 {
1045         union ctl_io *io = beio->io;
1046         struct cdevsw *csw;
1047         struct cdev *dev;
1048         struct ctl_lba_len_flags *lbalen = ARGS(io);
1049         struct scsi_get_lba_status_data *data;
1050         off_t roff, off;
1051         int error, ref, status;
1052
1053         DPRINTF("entered\n");
1054
1055         csw = devvn_refthread(be_lun->vn, &dev, &ref);
1056         if (csw == NULL) {
1057                 status = 0;     /* unknown up to the end */
1058                 off = be_lun->size_bytes;
1059                 goto done;
1060         }
1061         off = roff = ((off_t)lbalen->lba) * be_lun->cbe_lun.blocksize;
1062         error = csw->d_ioctl(dev, FIOSEEKHOLE, (caddr_t)&off, FREAD,
1063             curthread);
1064         if (error == 0 && off > roff)
1065                 status = 0;     /* mapped up to off */
1066         else {
1067                 error = csw->d_ioctl(dev, FIOSEEKDATA, (caddr_t)&off, FREAD,
1068                     curthread);
1069                 if (error == 0 && off > roff)
1070                         status = 1;     /* deallocated up to off */
1071                 else {
1072                         status = 0;     /* unknown up to the end */
1073                         off = be_lun->size_bytes;
1074                 }
1075         }
1076         dev_relthread(dev, ref);
1077
1078 done:
1079         data = (struct scsi_get_lba_status_data *)io->scsiio.kern_data_ptr;
1080         scsi_u64to8b(lbalen->lba, data->descr[0].addr);
1081         scsi_ulto4b(MIN(UINT32_MAX, off / be_lun->cbe_lun.blocksize -
1082             lbalen->lba), data->descr[0].length);
1083         data->descr[0].status = status;
1084
1085         ctl_complete_beio(beio);
1086 }
1087
1088 static void
1089 ctl_be_block_flush_dev(struct ctl_be_block_lun *be_lun,
1090                        struct ctl_be_block_io *beio)
1091 {
1092         struct bio *bio;
1093         struct cdevsw *csw;
1094         struct cdev *dev;
1095         int ref;
1096
1097         DPRINTF("entered\n");
1098
1099         /* This can't fail, it's a blocking allocation. */
1100         bio = g_alloc_bio();
1101
1102         bio->bio_cmd        = BIO_FLUSH;
1103         bio->bio_offset     = 0;
1104         bio->bio_data       = 0;
1105         bio->bio_done       = ctl_be_block_biodone;
1106         bio->bio_caller1    = beio;
1107         bio->bio_pblkno     = 0;
1108
1109         /*
1110          * We don't need to acquire the LUN lock here, because we are only
1111          * sending one bio, and so there is no other context to synchronize
1112          * with.
1113          */
1114         beio->num_bios_sent = 1;
1115         beio->send_complete = 1;
1116
1117         binuptime(&beio->ds_t0);
1118         devstat_start_transaction(be_lun->disk_stats, &beio->ds_t0);
1119
1120         csw = devvn_refthread(be_lun->vn, &dev, &ref);
1121         if (csw) {
1122                 bio->bio_dev = dev;
1123                 csw->d_strategy(bio);
1124                 dev_relthread(dev, ref);
1125         } else {
1126                 bio->bio_error = ENXIO;
1127                 ctl_be_block_biodone(bio);
1128         }
1129 }
1130
1131 static void
1132 ctl_be_block_unmap_dev_range(struct ctl_be_block_lun *be_lun,
1133                        struct ctl_be_block_io *beio,
1134                        uint64_t off, uint64_t len, int last)
1135 {
1136         struct bio *bio;
1137         uint64_t maxlen;
1138         struct cdevsw *csw;
1139         struct cdev *dev;
1140         int ref;
1141
1142         csw = devvn_refthread(be_lun->vn, &dev, &ref);
1143         maxlen = LONG_MAX - (LONG_MAX % be_lun->cbe_lun.blocksize);
1144         while (len > 0) {
1145                 bio = g_alloc_bio();
1146                 bio->bio_cmd        = BIO_DELETE;
1147                 bio->bio_dev        = dev;
1148                 bio->bio_offset     = off;
1149                 bio->bio_length     = MIN(len, maxlen);
1150                 bio->bio_data       = 0;
1151                 bio->bio_done       = ctl_be_block_biodone;
1152                 bio->bio_caller1    = beio;
1153                 bio->bio_pblkno     = off / be_lun->cbe_lun.blocksize;
1154
1155                 off += bio->bio_length;
1156                 len -= bio->bio_length;
1157
1158                 mtx_lock(&be_lun->io_lock);
1159                 beio->num_bios_sent++;
1160                 if (last && len == 0)
1161                         beio->send_complete = 1;
1162                 mtx_unlock(&be_lun->io_lock);
1163
1164                 if (csw) {
1165                         csw->d_strategy(bio);
1166                 } else {
1167                         bio->bio_error = ENXIO;
1168                         ctl_be_block_biodone(bio);
1169                 }
1170         }
1171         if (csw)
1172                 dev_relthread(dev, ref);
1173 }
1174
1175 static void
1176 ctl_be_block_unmap_dev(struct ctl_be_block_lun *be_lun,
1177                        struct ctl_be_block_io *beio)
1178 {
1179         union ctl_io *io;
1180         struct ctl_ptr_len_flags *ptrlen;
1181         struct scsi_unmap_desc *buf, *end;
1182         uint64_t len;
1183
1184         io = beio->io;
1185
1186         DPRINTF("entered\n");
1187
1188         binuptime(&beio->ds_t0);
1189         devstat_start_transaction(be_lun->disk_stats, &beio->ds_t0);
1190
1191         if (beio->io_offset == -1) {
1192                 beio->io_len = 0;
1193                 ptrlen = (struct ctl_ptr_len_flags *)&io->io_hdr.ctl_private[CTL_PRIV_LBA_LEN];
1194                 buf = (struct scsi_unmap_desc *)ptrlen->ptr;
1195                 end = buf + ptrlen->len / sizeof(*buf);
1196                 for (; buf < end; buf++) {
1197                         len = (uint64_t)scsi_4btoul(buf->length) *
1198                             be_lun->cbe_lun.blocksize;
1199                         beio->io_len += len;
1200                         ctl_be_block_unmap_dev_range(be_lun, beio,
1201                             scsi_8btou64(buf->lba) * be_lun->cbe_lun.blocksize,
1202                             len, (end - buf < 2) ? TRUE : FALSE);
1203                 }
1204         } else
1205                 ctl_be_block_unmap_dev_range(be_lun, beio,
1206                     beio->io_offset, beio->io_len, TRUE);
1207 }
1208
1209 static void
1210 ctl_be_block_dispatch_dev(struct ctl_be_block_lun *be_lun,
1211                           struct ctl_be_block_io *beio)
1212 {
1213         TAILQ_HEAD(, bio) queue = TAILQ_HEAD_INITIALIZER(queue);
1214         struct bio *bio;
1215         struct cdevsw *csw;
1216         struct cdev *dev;
1217         off_t cur_offset;
1218         int i, max_iosize, ref;
1219
1220         DPRINTF("entered\n");
1221         csw = devvn_refthread(be_lun->vn, &dev, &ref);
1222
1223         /*
1224          * We have to limit our I/O size to the maximum supported by the
1225          * backend device.
1226          */
1227         if (csw) {
1228                 max_iosize = dev->si_iosize_max;
1229                 if (max_iosize <= 0)
1230                         max_iosize = DFLTPHYS;
1231         } else
1232                 max_iosize = maxphys;
1233
1234         cur_offset = beio->io_offset;
1235         for (i = 0; i < beio->num_segs; i++) {
1236                 size_t cur_size;
1237                 uint8_t *cur_ptr;
1238
1239                 cur_size = beio->sg_segs[i].len;
1240                 cur_ptr = beio->sg_segs[i].addr;
1241
1242                 while (cur_size > 0) {
1243                         /* This can't fail, it's a blocking allocation. */
1244                         bio = g_alloc_bio();
1245
1246                         KASSERT(bio != NULL, ("g_alloc_bio() failed!\n"));
1247
1248                         bio->bio_cmd = beio->bio_cmd;
1249                         bio->bio_dev = dev;
1250                         bio->bio_caller1 = beio;
1251                         bio->bio_length = min(cur_size, max_iosize);
1252                         bio->bio_offset = cur_offset;
1253                         bio->bio_data = cur_ptr;
1254                         bio->bio_done = ctl_be_block_biodone;
1255                         bio->bio_pblkno = cur_offset / be_lun->cbe_lun.blocksize;
1256
1257                         cur_offset += bio->bio_length;
1258                         cur_ptr += bio->bio_length;
1259                         cur_size -= bio->bio_length;
1260
1261                         TAILQ_INSERT_TAIL(&queue, bio, bio_queue);
1262                         beio->num_bios_sent++;
1263                 }
1264         }
1265         beio->send_complete = 1;
1266         binuptime(&beio->ds_t0);
1267         devstat_start_transaction(be_lun->disk_stats, &beio->ds_t0);
1268
1269         /*
1270          * Fire off all allocated requests!
1271          */
1272         while ((bio = TAILQ_FIRST(&queue)) != NULL) {
1273                 TAILQ_REMOVE(&queue, bio, bio_queue);
1274                 if (csw)
1275                         csw->d_strategy(bio);
1276                 else {
1277                         bio->bio_error = ENXIO;
1278                         ctl_be_block_biodone(bio);
1279                 }
1280         }
1281         if (csw)
1282                 dev_relthread(dev, ref);
1283 }
1284
1285 static uint64_t
1286 ctl_be_block_getattr_dev(struct ctl_be_block_lun *be_lun, const char *attrname)
1287 {
1288         struct diocgattr_arg    arg;
1289         struct cdevsw *csw;
1290         struct cdev *dev;
1291         int error, ref;
1292
1293         csw = devvn_refthread(be_lun->vn, &dev, &ref);
1294         if (csw == NULL)
1295                 return (UINT64_MAX);
1296         strlcpy(arg.name, attrname, sizeof(arg.name));
1297         arg.len = sizeof(arg.value.off);
1298         if (csw->d_ioctl) {
1299                 error = csw->d_ioctl(dev, DIOCGATTR, (caddr_t)&arg, FREAD,
1300                     curthread);
1301         } else
1302                 error = ENODEV;
1303         dev_relthread(dev, ref);
1304         if (error != 0)
1305                 return (UINT64_MAX);
1306         return (arg.value.off);
1307 }
1308
1309 static void
1310 ctl_be_block_cw_dispatch_sync(struct ctl_be_block_lun *be_lun,
1311                             union ctl_io *io)
1312 {
1313         struct ctl_be_lun *cbe_lun = &be_lun->cbe_lun;
1314         struct ctl_be_block_io *beio;
1315         struct ctl_lba_len_flags *lbalen;
1316
1317         DPRINTF("entered\n");
1318         beio = (struct ctl_be_block_io *)PRIV(io)->ptr;
1319         lbalen = (struct ctl_lba_len_flags *)&io->io_hdr.ctl_private[CTL_PRIV_LBA_LEN];
1320
1321         beio->io_len = lbalen->len * cbe_lun->blocksize;
1322         beio->io_offset = lbalen->lba * cbe_lun->blocksize;
1323         beio->io_arg = (lbalen->flags & SSC_IMMED) != 0;
1324         beio->bio_cmd = BIO_FLUSH;
1325         beio->ds_trans_type = DEVSTAT_NO_DATA;
1326         DPRINTF("SYNC\n");
1327         be_lun->lun_flush(be_lun, beio);
1328 }
1329
1330 static void
1331 ctl_be_block_cw_done_ws(struct ctl_be_block_io *beio)
1332 {
1333         union ctl_io *io;
1334
1335         io = beio->io;
1336         ctl_free_beio(beio);
1337         if ((io->io_hdr.flags & CTL_FLAG_ABORT) ||
1338             ((io->io_hdr.status & CTL_STATUS_MASK) != CTL_STATUS_NONE &&
1339              (io->io_hdr.status & CTL_STATUS_MASK) != CTL_SUCCESS)) {
1340                 ctl_config_write_done(io);
1341                 return;
1342         }
1343
1344         ctl_be_block_config_write(io);
1345 }
1346
1347 static void
1348 ctl_be_block_cw_dispatch_ws(struct ctl_be_block_lun *be_lun,
1349                             union ctl_io *io)
1350 {
1351         struct ctl_be_block_softc *softc = be_lun->softc;
1352         struct ctl_be_lun *cbe_lun = &be_lun->cbe_lun;
1353         struct ctl_be_block_io *beio;
1354         struct ctl_lba_len_flags *lbalen;
1355         uint64_t len_left, lba;
1356         uint32_t pb, pbo, adj;
1357         int i, seglen;
1358         uint8_t *buf, *end;
1359
1360         DPRINTF("entered\n");
1361
1362         beio = (struct ctl_be_block_io *)PRIV(io)->ptr;
1363         lbalen = ARGS(io);
1364
1365         if (lbalen->flags & ~(SWS_LBDATA | SWS_UNMAP | SWS_ANCHOR | SWS_NDOB) ||
1366             (lbalen->flags & (SWS_UNMAP | SWS_ANCHOR) && be_lun->unmap == NULL)) {
1367                 ctl_free_beio(beio);
1368                 ctl_set_invalid_field(&io->scsiio,
1369                                       /*sks_valid*/ 1,
1370                                       /*command*/ 1,
1371                                       /*field*/ 1,
1372                                       /*bit_valid*/ 0,
1373                                       /*bit*/ 0);
1374                 ctl_config_write_done(io);
1375                 return;
1376         }
1377
1378         if (lbalen->flags & (SWS_UNMAP | SWS_ANCHOR)) {
1379                 beio->io_offset = lbalen->lba * cbe_lun->blocksize;
1380                 beio->io_len = (uint64_t)lbalen->len * cbe_lun->blocksize;
1381                 beio->bio_cmd = BIO_DELETE;
1382                 beio->ds_trans_type = DEVSTAT_FREE;
1383
1384                 be_lun->unmap(be_lun, beio);
1385                 return;
1386         }
1387
1388         beio->bio_cmd = BIO_WRITE;
1389         beio->ds_trans_type = DEVSTAT_WRITE;
1390
1391         DPRINTF("WRITE SAME at LBA %jx len %u\n",
1392                (uintmax_t)lbalen->lba, lbalen->len);
1393
1394         pb = cbe_lun->blocksize << be_lun->cbe_lun.pblockexp;
1395         if (be_lun->cbe_lun.pblockoff > 0)
1396                 pbo = pb - cbe_lun->blocksize * be_lun->cbe_lun.pblockoff;
1397         else
1398                 pbo = 0;
1399         len_left = (uint64_t)lbalen->len * cbe_lun->blocksize;
1400         for (i = 0, lba = 0; i < CTLBLK_MAX_SEGS && len_left > 0; i++) {
1401                 /*
1402                  * Setup the S/G entry for this chunk.
1403                  */
1404                 seglen = MIN(CTLBLK_MAX_SEG, len_left);
1405                 if (pb > cbe_lun->blocksize) {
1406                         adj = ((lbalen->lba + lba) * cbe_lun->blocksize +
1407                             seglen - pbo) % pb;
1408                         if (seglen > adj)
1409                                 seglen -= adj;
1410                         else
1411                                 seglen -= seglen % cbe_lun->blocksize;
1412                 } else
1413                         seglen -= seglen % cbe_lun->blocksize;
1414                 ctl_alloc_seg(softc, &beio->sg_segs[i], seglen);
1415
1416                 DPRINTF("segment %d addr %p len %zd\n", i,
1417                         beio->sg_segs[i].addr, beio->sg_segs[i].len);
1418
1419                 beio->num_segs++;
1420                 len_left -= seglen;
1421
1422                 buf = beio->sg_segs[i].addr;
1423                 end = buf + seglen;
1424                 for (; buf < end; buf += cbe_lun->blocksize) {
1425                         if (lbalen->flags & SWS_NDOB) {
1426                                 memset(buf, 0, cbe_lun->blocksize);
1427                         } else {
1428                                 memcpy(buf, io->scsiio.kern_data_ptr,
1429                                     cbe_lun->blocksize);
1430                         }
1431                         if (lbalen->flags & SWS_LBDATA)
1432                                 scsi_ulto4b(lbalen->lba + lba, buf);
1433                         lba++;
1434                 }
1435         }
1436
1437         beio->io_offset = lbalen->lba * cbe_lun->blocksize;
1438         beio->io_len = lba * cbe_lun->blocksize;
1439
1440         /* We can not do all in one run. Correct and schedule rerun. */
1441         if (len_left > 0) {
1442                 lbalen->lba += lba;
1443                 lbalen->len -= lba;
1444                 beio->beio_cont = ctl_be_block_cw_done_ws;
1445         }
1446
1447         be_lun->dispatch(be_lun, beio);
1448 }
1449
1450 static void
1451 ctl_be_block_cw_dispatch_unmap(struct ctl_be_block_lun *be_lun,
1452                             union ctl_io *io)
1453 {
1454         struct ctl_be_block_io *beio;
1455         struct ctl_ptr_len_flags *ptrlen;
1456
1457         DPRINTF("entered\n");
1458
1459         beio = (struct ctl_be_block_io *)PRIV(io)->ptr;
1460         ptrlen = (struct ctl_ptr_len_flags *)&io->io_hdr.ctl_private[CTL_PRIV_LBA_LEN];
1461
1462         if ((ptrlen->flags & ~SU_ANCHOR) != 0 || be_lun->unmap == NULL) {
1463                 ctl_free_beio(beio);
1464                 ctl_set_invalid_field(&io->scsiio,
1465                                       /*sks_valid*/ 0,
1466                                       /*command*/ 1,
1467                                       /*field*/ 0,
1468                                       /*bit_valid*/ 0,
1469                                       /*bit*/ 0);
1470                 ctl_config_write_done(io);
1471                 return;
1472         }
1473
1474         beio->io_len = 0;
1475         beio->io_offset = -1;
1476         beio->bio_cmd = BIO_DELETE;
1477         beio->ds_trans_type = DEVSTAT_FREE;
1478         DPRINTF("UNMAP\n");
1479         be_lun->unmap(be_lun, beio);
1480 }
1481
1482 static void
1483 ctl_be_block_cr_done(struct ctl_be_block_io *beio)
1484 {
1485         union ctl_io *io;
1486
1487         io = beio->io;
1488         ctl_free_beio(beio);
1489         ctl_config_read_done(io);
1490 }
1491
1492 static void
1493 ctl_be_block_cr_dispatch(struct ctl_be_block_lun *be_lun,
1494                          union ctl_io *io)
1495 {
1496         struct ctl_be_block_io *beio;
1497         struct ctl_be_block_softc *softc;
1498
1499         DPRINTF("entered\n");
1500
1501         softc = be_lun->softc;
1502         beio = ctl_alloc_beio(softc);
1503         beio->io = io;
1504         beio->lun = be_lun;
1505         beio->beio_cont = ctl_be_block_cr_done;
1506         PRIV(io)->ptr = (void *)beio;
1507
1508         switch (io->scsiio.cdb[0]) {
1509         case SERVICE_ACTION_IN:         /* GET LBA STATUS */
1510                 beio->bio_cmd = -1;
1511                 beio->ds_trans_type = DEVSTAT_NO_DATA;
1512                 beio->ds_tag_type = DEVSTAT_TAG_ORDERED;
1513                 beio->io_len = 0;
1514                 if (be_lun->get_lba_status)
1515                         be_lun->get_lba_status(be_lun, beio);
1516                 else
1517                         ctl_be_block_cr_done(beio);
1518                 break;
1519         default:
1520                 panic("Unhandled CDB type %#x", io->scsiio.cdb[0]);
1521                 break;
1522         }
1523 }
1524
1525 static void
1526 ctl_be_block_cw_done(struct ctl_be_block_io *beio)
1527 {
1528         union ctl_io *io;
1529
1530         io = beio->io;
1531         ctl_free_beio(beio);
1532         ctl_config_write_done(io);
1533 }
1534
1535 static void
1536 ctl_be_block_cw_dispatch(struct ctl_be_block_lun *be_lun,
1537                          union ctl_io *io)
1538 {
1539         struct ctl_be_block_io *beio;
1540         struct ctl_be_block_softc *softc;
1541
1542         DPRINTF("entered\n");
1543
1544         softc = be_lun->softc;
1545         beio = ctl_alloc_beio(softc);
1546         beio->io = io;
1547         beio->lun = be_lun;
1548         beio->beio_cont = ctl_be_block_cw_done;
1549         switch (io->scsiio.tag_type) {
1550         case CTL_TAG_ORDERED:
1551                 beio->ds_tag_type = DEVSTAT_TAG_ORDERED;
1552                 break;
1553         case CTL_TAG_HEAD_OF_QUEUE:
1554                 beio->ds_tag_type = DEVSTAT_TAG_HEAD;
1555                 break;
1556         case CTL_TAG_UNTAGGED:
1557         case CTL_TAG_SIMPLE:
1558         case CTL_TAG_ACA:
1559         default:
1560                 beio->ds_tag_type = DEVSTAT_TAG_SIMPLE;
1561                 break;
1562         }
1563         PRIV(io)->ptr = (void *)beio;
1564
1565         switch (io->scsiio.cdb[0]) {
1566         case SYNCHRONIZE_CACHE:
1567         case SYNCHRONIZE_CACHE_16:
1568                 ctl_be_block_cw_dispatch_sync(be_lun, io);
1569                 break;
1570         case WRITE_SAME_10:
1571         case WRITE_SAME_16:
1572                 ctl_be_block_cw_dispatch_ws(be_lun, io);
1573                 break;
1574         case UNMAP:
1575                 ctl_be_block_cw_dispatch_unmap(be_lun, io);
1576                 break;
1577         default:
1578                 panic("Unhandled CDB type %#x", io->scsiio.cdb[0]);
1579                 break;
1580         }
1581 }
1582
1583 SDT_PROBE_DEFINE1(cbb, , read, start, "uint64_t");
1584 SDT_PROBE_DEFINE1(cbb, , write, start, "uint64_t");
1585 SDT_PROBE_DEFINE1(cbb, , read, alloc_done, "uint64_t");
1586 SDT_PROBE_DEFINE1(cbb, , write, alloc_done, "uint64_t");
1587
1588 static void
1589 ctl_be_block_next(struct ctl_be_block_io *beio)
1590 {
1591         struct ctl_be_block_lun *be_lun;
1592         union ctl_io *io;
1593
1594         io = beio->io;
1595         be_lun = beio->lun;
1596         ctl_free_beio(beio);
1597         if ((io->io_hdr.flags & CTL_FLAG_ABORT) ||
1598             ((io->io_hdr.status & CTL_STATUS_MASK) != CTL_STATUS_NONE &&
1599              (io->io_hdr.status & CTL_STATUS_MASK) != CTL_SUCCESS)) {
1600                 ctl_data_submit_done(io);
1601                 return;
1602         }
1603
1604         io->io_hdr.status &= ~CTL_STATUS_MASK;
1605         io->io_hdr.status |= CTL_STATUS_NONE;
1606
1607         mtx_lock(&be_lun->queue_lock);
1608         STAILQ_INSERT_TAIL(&be_lun->input_queue, &io->io_hdr, links);
1609         mtx_unlock(&be_lun->queue_lock);
1610         taskqueue_enqueue(be_lun->io_taskqueue, &be_lun->io_task);
1611 }
1612
1613 static void
1614 ctl_be_block_dispatch(struct ctl_be_block_lun *be_lun,
1615                            union ctl_io *io)
1616 {
1617         struct ctl_be_lun *cbe_lun = &be_lun->cbe_lun;
1618         struct ctl_be_block_io *beio;
1619         struct ctl_be_block_softc *softc;
1620         struct ctl_lba_len_flags *lbalen;
1621         struct ctl_ptr_len_flags *bptrlen;
1622         uint64_t len_left, lbas;
1623         int i;
1624
1625         softc = be_lun->softc;
1626
1627         DPRINTF("entered\n");
1628
1629         lbalen = ARGS(io);
1630         if (lbalen->flags & CTL_LLF_WRITE) {
1631                 SDT_PROBE0(cbb, , write, start);
1632         } else {
1633                 SDT_PROBE0(cbb, , read, start);
1634         }
1635
1636         beio = ctl_alloc_beio(softc);
1637         beio->io = io;
1638         beio->lun = be_lun;
1639         bptrlen = PRIV(io);
1640         bptrlen->ptr = (void *)beio;
1641
1642         switch (io->scsiio.tag_type) {
1643         case CTL_TAG_ORDERED:
1644                 beio->ds_tag_type = DEVSTAT_TAG_ORDERED;
1645                 break;
1646         case CTL_TAG_HEAD_OF_QUEUE:
1647                 beio->ds_tag_type = DEVSTAT_TAG_HEAD;
1648                 break;
1649         case CTL_TAG_UNTAGGED:
1650         case CTL_TAG_SIMPLE:
1651         case CTL_TAG_ACA:
1652         default:
1653                 beio->ds_tag_type = DEVSTAT_TAG_SIMPLE;
1654                 break;
1655         }
1656
1657         if (lbalen->flags & CTL_LLF_WRITE) {
1658                 beio->bio_cmd = BIO_WRITE;
1659                 beio->ds_trans_type = DEVSTAT_WRITE;
1660         } else {
1661                 beio->bio_cmd = BIO_READ;
1662                 beio->ds_trans_type = DEVSTAT_READ;
1663         }
1664
1665         DPRINTF("%s at LBA %jx len %u @%ju\n",
1666                (beio->bio_cmd == BIO_READ) ? "READ" : "WRITE",
1667                (uintmax_t)lbalen->lba, lbalen->len, bptrlen->len);
1668         lbas = CTLBLK_MAX_IO_SIZE;
1669         if (lbalen->flags & CTL_LLF_COMPARE) {
1670                 beio->two_sglists = 1;
1671                 lbas /= 2;
1672         }
1673         lbas = MIN(lbalen->len - bptrlen->len, lbas / cbe_lun->blocksize);
1674         beio->io_offset = (lbalen->lba + bptrlen->len) * cbe_lun->blocksize;
1675         beio->io_len = lbas * cbe_lun->blocksize;
1676         bptrlen->len += lbas;
1677
1678         for (i = 0, len_left = beio->io_len; len_left > 0; i++) {
1679                 KASSERT(i < CTLBLK_MAX_SEGS, ("Too many segs (%d >= %d)",
1680                     i, CTLBLK_MAX_SEGS));
1681
1682                 /*
1683                  * Setup the S/G entry for this chunk.
1684                  */
1685                 ctl_alloc_seg(softc, &beio->sg_segs[i],
1686                     MIN(CTLBLK_MAX_SEG, len_left));
1687
1688                 DPRINTF("segment %d addr %p len %zd\n", i,
1689                         beio->sg_segs[i].addr, beio->sg_segs[i].len);
1690
1691                 /* Set up second segment for compare operation. */
1692                 if (beio->two_sglists) {
1693                         ctl_alloc_seg(softc,
1694                             &beio->sg_segs[i + CTLBLK_HALF_SEGS],
1695                             beio->sg_segs[i].len);
1696                 }
1697
1698                 beio->num_segs++;
1699                 len_left -= beio->sg_segs[i].len;
1700         }
1701         if (bptrlen->len < lbalen->len)
1702                 beio->beio_cont = ctl_be_block_next;
1703         io->scsiio.be_move_done = ctl_be_block_move_done;
1704         /* For compare we have separate S/G lists for read and datamove. */
1705         if (beio->two_sglists)
1706                 io->scsiio.kern_data_ptr = (uint8_t *)&beio->sg_segs[CTLBLK_HALF_SEGS];
1707         else
1708                 io->scsiio.kern_data_ptr = (uint8_t *)beio->sg_segs;
1709         io->scsiio.kern_data_len = beio->io_len;
1710         io->scsiio.kern_sg_entries = beio->num_segs;
1711         io->scsiio.kern_data_ref = ctl_refcnt_beio;
1712         io->scsiio.kern_data_arg = beio;
1713         io->io_hdr.flags |= CTL_FLAG_ALLOCATED;
1714
1715         /*
1716          * For the read case, we need to read the data into our buffers and
1717          * then we can send it back to the user.  For the write case, we
1718          * need to get the data from the user first.
1719          */
1720         if (beio->bio_cmd == BIO_READ) {
1721                 SDT_PROBE0(cbb, , read, alloc_done);
1722                 be_lun->dispatch(be_lun, beio);
1723         } else {
1724                 SDT_PROBE0(cbb, , write, alloc_done);
1725                 ctl_datamove(io);
1726         }
1727 }
1728
1729 static void
1730 ctl_be_block_worker(void *context, int pending)
1731 {
1732         struct ctl_be_block_lun *be_lun = (struct ctl_be_block_lun *)context;
1733         struct ctl_be_lun *cbe_lun = &be_lun->cbe_lun;
1734         union ctl_io *io;
1735         struct ctl_be_block_io *beio;
1736
1737         DPRINTF("entered\n");
1738         /*
1739          * Fetch and process I/Os from all queues.  If we detect LUN
1740          * CTL_LUN_FLAG_NO_MEDIA status here -- it is result of a race,
1741          * so make response maximally opaque to not confuse initiator.
1742          */
1743         for (;;) {
1744                 mtx_lock(&be_lun->queue_lock);
1745                 io = (union ctl_io *)STAILQ_FIRST(&be_lun->datamove_queue);
1746                 if (io != NULL) {
1747                         DPRINTF("datamove queue\n");
1748                         STAILQ_REMOVE_HEAD(&be_lun->datamove_queue, links);
1749                         mtx_unlock(&be_lun->queue_lock);
1750                         beio = (struct ctl_be_block_io *)PRIV(io)->ptr;
1751                         if (cbe_lun->flags & CTL_LUN_FLAG_NO_MEDIA) {
1752                                 ctl_set_busy(&io->scsiio);
1753                                 ctl_complete_beio(beio);
1754                                 continue;
1755                         }
1756                         be_lun->dispatch(be_lun, beio);
1757                         continue;
1758                 }
1759                 io = (union ctl_io *)STAILQ_FIRST(&be_lun->config_write_queue);
1760                 if (io != NULL) {
1761                         DPRINTF("config write queue\n");
1762                         STAILQ_REMOVE_HEAD(&be_lun->config_write_queue, links);
1763                         mtx_unlock(&be_lun->queue_lock);
1764                         if (cbe_lun->flags & CTL_LUN_FLAG_NO_MEDIA) {
1765                                 ctl_set_busy(&io->scsiio);
1766                                 ctl_config_write_done(io);
1767                                 continue;
1768                         }
1769                         ctl_be_block_cw_dispatch(be_lun, io);
1770                         continue;
1771                 }
1772                 io = (union ctl_io *)STAILQ_FIRST(&be_lun->config_read_queue);
1773                 if (io != NULL) {
1774                         DPRINTF("config read queue\n");
1775                         STAILQ_REMOVE_HEAD(&be_lun->config_read_queue, links);
1776                         mtx_unlock(&be_lun->queue_lock);
1777                         if (cbe_lun->flags & CTL_LUN_FLAG_NO_MEDIA) {
1778                                 ctl_set_busy(&io->scsiio);
1779                                 ctl_config_read_done(io);
1780                                 continue;
1781                         }
1782                         ctl_be_block_cr_dispatch(be_lun, io);
1783                         continue;
1784                 }
1785                 io = (union ctl_io *)STAILQ_FIRST(&be_lun->input_queue);
1786                 if (io != NULL) {
1787                         DPRINTF("input queue\n");
1788                         STAILQ_REMOVE_HEAD(&be_lun->input_queue, links);
1789                         mtx_unlock(&be_lun->queue_lock);
1790                         if (cbe_lun->flags & CTL_LUN_FLAG_NO_MEDIA) {
1791                                 ctl_set_busy(&io->scsiio);
1792                                 ctl_data_submit_done(io);
1793                                 continue;
1794                         }
1795                         ctl_be_block_dispatch(be_lun, io);
1796                         continue;
1797                 }
1798
1799                 /*
1800                  * If we get here, there is no work left in the queues, so
1801                  * just break out and let the task queue go to sleep.
1802                  */
1803                 mtx_unlock(&be_lun->queue_lock);
1804                 break;
1805         }
1806 }
1807
1808 /*
1809  * Entry point from CTL to the backend for I/O.  We queue everything to a
1810  * work thread, so this just puts the I/O on a queue and wakes up the
1811  * thread.
1812  */
1813 static int
1814 ctl_be_block_submit(union ctl_io *io)
1815 {
1816         struct ctl_be_block_lun *be_lun;
1817
1818         DPRINTF("entered\n");
1819
1820         be_lun = (struct ctl_be_block_lun *)CTL_BACKEND_LUN(io);
1821
1822         KASSERT(io->io_hdr.io_type == CTL_IO_SCSI,
1823             ("%s: unexpected I/O type %x", __func__, io->io_hdr.io_type));
1824
1825         PRIV(io)->len = 0;
1826
1827         mtx_lock(&be_lun->queue_lock);
1828         STAILQ_INSERT_TAIL(&be_lun->input_queue, &io->io_hdr, links);
1829         mtx_unlock(&be_lun->queue_lock);
1830         taskqueue_enqueue(be_lun->io_taskqueue, &be_lun->io_task);
1831
1832         return (CTL_RETVAL_COMPLETE);
1833 }
1834
1835 static int
1836 ctl_be_block_ioctl(struct cdev *dev, u_long cmd, caddr_t addr,
1837                         int flag, struct thread *td)
1838 {
1839         struct ctl_be_block_softc *softc = &backend_block_softc;
1840         int error;
1841
1842         error = 0;
1843         switch (cmd) {
1844         case CTL_LUN_REQ: {
1845                 struct ctl_lun_req *lun_req;
1846
1847                 lun_req = (struct ctl_lun_req *)addr;
1848
1849                 switch (lun_req->reqtype) {
1850                 case CTL_LUNREQ_CREATE:
1851                         error = ctl_be_block_create(softc, lun_req);
1852                         break;
1853                 case CTL_LUNREQ_RM:
1854                         error = ctl_be_block_rm(softc, lun_req);
1855                         break;
1856                 case CTL_LUNREQ_MODIFY:
1857                         error = ctl_be_block_modify(softc, lun_req);
1858                         break;
1859                 default:
1860                         lun_req->status = CTL_LUN_ERROR;
1861                         snprintf(lun_req->error_str, sizeof(lun_req->error_str),
1862                                  "invalid LUN request type %d",
1863                                  lun_req->reqtype);
1864                         break;
1865                 }
1866                 break;
1867         }
1868         default:
1869                 error = ENOTTY;
1870                 break;
1871         }
1872
1873         return (error);
1874 }
1875
1876 static int
1877 ctl_be_block_open_file(struct ctl_be_block_lun *be_lun, struct ctl_lun_req *req)
1878 {
1879         struct ctl_be_lun *cbe_lun;
1880         struct ctl_be_block_filedata *file_data;
1881         struct ctl_lun_create_params *params;
1882         const char                   *value;
1883         struct vattr                  vattr;
1884         off_t                         ps, pss, po, pos, us, uss, uo, uos;
1885         int                           error;
1886         long                          pconf;
1887
1888         cbe_lun = &be_lun->cbe_lun;
1889         file_data = &be_lun->backend.file;
1890         params = &be_lun->params;
1891
1892         be_lun->dev_type = CTL_BE_BLOCK_FILE;
1893         be_lun->dispatch = ctl_be_block_dispatch_file;
1894         be_lun->lun_flush = ctl_be_block_flush_file;
1895         be_lun->get_lba_status = ctl_be_block_gls_file;
1896         be_lun->getattr = ctl_be_block_getattr_file;
1897         be_lun->unmap = ctl_be_block_unmap_file;
1898         cbe_lun->flags &= ~CTL_LUN_FLAG_UNMAP;
1899
1900         error = VOP_GETATTR(be_lun->vn, &vattr, curthread->td_ucred);
1901         if (error != 0) {
1902                 snprintf(req->error_str, sizeof(req->error_str),
1903                          "error calling VOP_GETATTR() for file %s",
1904                          be_lun->dev_path);
1905                 return (error);
1906         }
1907
1908         error = VOP_PATHCONF(be_lun->vn, _PC_DEALLOC_PRESENT, &pconf);
1909         if (error != 0) {
1910                 snprintf(req->error_str, sizeof(req->error_str),
1911                     "error calling VOP_PATHCONF() for file %s",
1912                     be_lun->dev_path);
1913                 return (error);
1914         }
1915         if (pconf == 1)
1916                 cbe_lun->flags |= CTL_LUN_FLAG_UNMAP;
1917
1918         file_data->cred = crhold(curthread->td_ucred);
1919         if (params->lun_size_bytes != 0)
1920                 be_lun->size_bytes = params->lun_size_bytes;
1921         else
1922                 be_lun->size_bytes = vattr.va_size;
1923
1924         /*
1925          * For files we can use any logical block size.  Prefer 512 bytes
1926          * for compatibility reasons.  If file's vattr.va_blocksize
1927          * (preferred I/O block size) is bigger and multiple to chosen
1928          * logical block size -- report it as physical block size.
1929          */
1930         if (params->blocksize_bytes != 0)
1931                 cbe_lun->blocksize = params->blocksize_bytes;
1932         else if (cbe_lun->lun_type == T_CDROM)
1933                 cbe_lun->blocksize = 2048;
1934         else
1935                 cbe_lun->blocksize = 512;
1936         be_lun->size_blocks = be_lun->size_bytes / cbe_lun->blocksize;
1937         cbe_lun->maxlba = (be_lun->size_blocks == 0) ?
1938             0 : (be_lun->size_blocks - 1);
1939
1940         us = ps = vattr.va_blocksize;
1941         uo = po = 0;
1942
1943         value = dnvlist_get_string(cbe_lun->options, "pblocksize", NULL);
1944         if (value != NULL)
1945                 ctl_expand_number(value, &ps);
1946         value = dnvlist_get_string(cbe_lun->options, "pblockoffset", NULL);
1947         if (value != NULL)
1948                 ctl_expand_number(value, &po);
1949         pss = ps / cbe_lun->blocksize;
1950         pos = po / cbe_lun->blocksize;
1951         if ((pss > 0) && (pss * cbe_lun->blocksize == ps) && (pss >= pos) &&
1952             ((pss & (pss - 1)) == 0) && (pos * cbe_lun->blocksize == po)) {
1953                 cbe_lun->pblockexp = fls(pss) - 1;
1954                 cbe_lun->pblockoff = (pss - pos) % pss;
1955         }
1956
1957         value = dnvlist_get_string(cbe_lun->options, "ublocksize", NULL);
1958         if (value != NULL)
1959                 ctl_expand_number(value, &us);
1960         value = dnvlist_get_string(cbe_lun->options, "ublockoffset", NULL);
1961         if (value != NULL)
1962                 ctl_expand_number(value, &uo);
1963         uss = us / cbe_lun->blocksize;
1964         uos = uo / cbe_lun->blocksize;
1965         if ((uss > 0) && (uss * cbe_lun->blocksize == us) && (uss >= uos) &&
1966             ((uss & (uss - 1)) == 0) && (uos * cbe_lun->blocksize == uo)) {
1967                 cbe_lun->ublockexp = fls(uss) - 1;
1968                 cbe_lun->ublockoff = (uss - uos) % uss;
1969         }
1970
1971         /*
1972          * Sanity check.  The media size has to be at least one
1973          * sector long.
1974          */
1975         if (be_lun->size_bytes < cbe_lun->blocksize) {
1976                 error = EINVAL;
1977                 snprintf(req->error_str, sizeof(req->error_str),
1978                          "file %s size %ju < block size %u", be_lun->dev_path,
1979                          (uintmax_t)be_lun->size_bytes, cbe_lun->blocksize);
1980         }
1981
1982         cbe_lun->opttxferlen = CTLBLK_MAX_IO_SIZE / cbe_lun->blocksize;
1983         return (error);
1984 }
1985
1986 static int
1987 ctl_be_block_open_dev(struct ctl_be_block_lun *be_lun, struct ctl_lun_req *req)
1988 {
1989         struct ctl_be_lun *cbe_lun = &be_lun->cbe_lun;
1990         struct ctl_lun_create_params *params;
1991         struct cdevsw                *csw;
1992         struct cdev                  *dev;
1993         const char                   *value;
1994         int                           error, atomic, maxio, ref, unmap, tmp;
1995         off_t                         ps, pss, po, pos, us, uss, uo, uos, otmp;
1996
1997         params = &be_lun->params;
1998
1999         be_lun->dev_type = CTL_BE_BLOCK_DEV;
2000         csw = devvn_refthread(be_lun->vn, &dev, &ref);
2001         if (csw == NULL)
2002                 return (ENXIO);
2003         if (strcmp(csw->d_name, "zvol") == 0) {
2004                 be_lun->dispatch = ctl_be_block_dispatch_zvol;
2005                 be_lun->get_lba_status = ctl_be_block_gls_zvol;
2006                 atomic = maxio = CTLBLK_MAX_IO_SIZE;
2007         } else {
2008                 be_lun->dispatch = ctl_be_block_dispatch_dev;
2009                 be_lun->get_lba_status = NULL;
2010                 atomic = 0;
2011                 maxio = dev->si_iosize_max;
2012                 if (maxio <= 0)
2013                         maxio = DFLTPHYS;
2014                 if (maxio > CTLBLK_MAX_SEG)
2015                         maxio = CTLBLK_MAX_SEG;
2016         }
2017         be_lun->lun_flush = ctl_be_block_flush_dev;
2018         be_lun->getattr = ctl_be_block_getattr_dev;
2019         be_lun->unmap = ctl_be_block_unmap_dev;
2020
2021         if (!csw->d_ioctl) {
2022                 dev_relthread(dev, ref);
2023                 snprintf(req->error_str, sizeof(req->error_str),
2024                          "no d_ioctl for device %s!", be_lun->dev_path);
2025                 return (ENODEV);
2026         }
2027
2028         error = csw->d_ioctl(dev, DIOCGSECTORSIZE, (caddr_t)&tmp, FREAD,
2029                                curthread);
2030         if (error) {
2031                 dev_relthread(dev, ref);
2032                 snprintf(req->error_str, sizeof(req->error_str),
2033                          "error %d returned for DIOCGSECTORSIZE ioctl "
2034                          "on %s!", error, be_lun->dev_path);
2035                 return (error);
2036         }
2037
2038         /*
2039          * If the user has asked for a blocksize that is greater than the
2040          * backing device's blocksize, we can do it only if the blocksize
2041          * the user is asking for is an even multiple of the underlying
2042          * device's blocksize.
2043          */
2044         if ((params->blocksize_bytes != 0) &&
2045             (params->blocksize_bytes >= tmp)) {
2046                 if (params->blocksize_bytes % tmp == 0) {
2047                         cbe_lun->blocksize = params->blocksize_bytes;
2048                 } else {
2049                         dev_relthread(dev, ref);
2050                         snprintf(req->error_str, sizeof(req->error_str),
2051                                  "requested blocksize %u is not an even "
2052                                  "multiple of backing device blocksize %u",
2053                                  params->blocksize_bytes, tmp);
2054                         return (EINVAL);
2055                 }
2056         } else if (params->blocksize_bytes != 0) {
2057                 dev_relthread(dev, ref);
2058                 snprintf(req->error_str, sizeof(req->error_str),
2059                          "requested blocksize %u < backing device "
2060                          "blocksize %u", params->blocksize_bytes, tmp);
2061                 return (EINVAL);
2062         } else if (cbe_lun->lun_type == T_CDROM)
2063                 cbe_lun->blocksize = MAX(tmp, 2048);
2064         else
2065                 cbe_lun->blocksize = tmp;
2066
2067         error = csw->d_ioctl(dev, DIOCGMEDIASIZE, (caddr_t)&otmp, FREAD,
2068                              curthread);
2069         if (error) {
2070                 dev_relthread(dev, ref);
2071                 snprintf(req->error_str, sizeof(req->error_str),
2072                          "error %d returned for DIOCGMEDIASIZE "
2073                          " ioctl on %s!", error,
2074                          be_lun->dev_path);
2075                 return (error);
2076         }
2077
2078         if (params->lun_size_bytes != 0) {
2079                 if (params->lun_size_bytes > otmp) {
2080                         dev_relthread(dev, ref);
2081                         snprintf(req->error_str, sizeof(req->error_str),
2082                                  "requested LUN size %ju > backing device "
2083                                  "size %ju",
2084                                  (uintmax_t)params->lun_size_bytes,
2085                                  (uintmax_t)otmp);
2086                         return (EINVAL);
2087                 }
2088
2089                 be_lun->size_bytes = params->lun_size_bytes;
2090         } else
2091                 be_lun->size_bytes = otmp;
2092         be_lun->size_blocks = be_lun->size_bytes / cbe_lun->blocksize;
2093         cbe_lun->maxlba = (be_lun->size_blocks == 0) ?
2094             0 : (be_lun->size_blocks - 1);
2095
2096         error = csw->d_ioctl(dev, DIOCGSTRIPESIZE, (caddr_t)&ps, FREAD,
2097             curthread);
2098         if (error)
2099                 ps = po = 0;
2100         else {
2101                 error = csw->d_ioctl(dev, DIOCGSTRIPEOFFSET, (caddr_t)&po,
2102                     FREAD, curthread);
2103                 if (error)
2104                         po = 0;
2105         }
2106         us = ps;
2107         uo = po;
2108
2109         value = dnvlist_get_string(cbe_lun->options, "pblocksize", NULL);
2110         if (value != NULL)
2111                 ctl_expand_number(value, &ps);
2112         value = dnvlist_get_string(cbe_lun->options, "pblockoffset", NULL);
2113         if (value != NULL)
2114                 ctl_expand_number(value, &po);
2115         pss = ps / cbe_lun->blocksize;
2116         pos = po / cbe_lun->blocksize;
2117         if ((pss > 0) && (pss * cbe_lun->blocksize == ps) && (pss >= pos) &&
2118             ((pss & (pss - 1)) == 0) && (pos * cbe_lun->blocksize == po)) {
2119                 cbe_lun->pblockexp = fls(pss) - 1;
2120                 cbe_lun->pblockoff = (pss - pos) % pss;
2121         }
2122
2123         value = dnvlist_get_string(cbe_lun->options, "ublocksize", NULL);
2124         if (value != NULL)
2125                 ctl_expand_number(value, &us);
2126         value = dnvlist_get_string(cbe_lun->options, "ublockoffset", NULL);
2127         if (value != NULL)
2128                 ctl_expand_number(value, &uo);
2129         uss = us / cbe_lun->blocksize;
2130         uos = uo / cbe_lun->blocksize;
2131         if ((uss > 0) && (uss * cbe_lun->blocksize == us) && (uss >= uos) &&
2132             ((uss & (uss - 1)) == 0) && (uos * cbe_lun->blocksize == uo)) {
2133                 cbe_lun->ublockexp = fls(uss) - 1;
2134                 cbe_lun->ublockoff = (uss - uos) % uss;
2135         }
2136
2137         cbe_lun->atomicblock = atomic / cbe_lun->blocksize;
2138         cbe_lun->opttxferlen = maxio / cbe_lun->blocksize;
2139
2140         if (be_lun->dispatch == ctl_be_block_dispatch_zvol) {
2141                 unmap = 1;
2142         } else {
2143                 struct diocgattr_arg    arg;
2144
2145                 strlcpy(arg.name, "GEOM::candelete", sizeof(arg.name));
2146                 arg.len = sizeof(arg.value.i);
2147                 error = csw->d_ioctl(dev, DIOCGATTR, (caddr_t)&arg, FREAD,
2148                     curthread);
2149                 unmap = (error == 0) ? arg.value.i : 0;
2150         }
2151         value = dnvlist_get_string(cbe_lun->options, "unmap", NULL);
2152         if (value != NULL)
2153                 unmap = (strcmp(value, "on") == 0);
2154         if (unmap)
2155                 cbe_lun->flags |= CTL_LUN_FLAG_UNMAP;
2156         else
2157                 cbe_lun->flags &= ~CTL_LUN_FLAG_UNMAP;
2158
2159         dev_relthread(dev, ref);
2160         return (0);
2161 }
2162
2163 static int
2164 ctl_be_block_close(struct ctl_be_block_lun *be_lun)
2165 {
2166         struct ctl_be_lun *cbe_lun = &be_lun->cbe_lun;
2167         int flags;
2168
2169         if (be_lun->vn) {
2170                 flags = FREAD;
2171                 if ((cbe_lun->flags & CTL_LUN_FLAG_READONLY) == 0)
2172                         flags |= FWRITE;
2173                 (void)vn_close(be_lun->vn, flags, NOCRED, curthread);
2174                 be_lun->vn = NULL;
2175
2176                 switch (be_lun->dev_type) {
2177                 case CTL_BE_BLOCK_DEV:
2178                         break;
2179                 case CTL_BE_BLOCK_FILE:
2180                         if (be_lun->backend.file.cred != NULL) {
2181                                 crfree(be_lun->backend.file.cred);
2182                                 be_lun->backend.file.cred = NULL;
2183                         }
2184                         break;
2185                 case CTL_BE_BLOCK_NONE:
2186                         break;
2187                 default:
2188                         panic("Unexpected backend type %d", be_lun->dev_type);
2189                         break;
2190                 }
2191                 be_lun->dev_type = CTL_BE_BLOCK_NONE;
2192         }
2193         return (0);
2194 }
2195
2196 static int
2197 ctl_be_block_open(struct ctl_be_block_lun *be_lun, struct ctl_lun_req *req)
2198 {
2199         struct ctl_be_lun *cbe_lun = &be_lun->cbe_lun;
2200         struct nameidata nd;
2201         const char      *value;
2202         int              error, flags;
2203
2204         error = 0;
2205         if (rootvnode == NULL) {
2206                 snprintf(req->error_str, sizeof(req->error_str),
2207                          "Root filesystem is not mounted");
2208                 return (1);
2209         }
2210         pwd_ensure_dirs();
2211
2212         value = dnvlist_get_string(cbe_lun->options, "file", NULL);
2213         if (value == NULL) {
2214                 snprintf(req->error_str, sizeof(req->error_str),
2215                          "no file argument specified");
2216                 return (1);
2217         }
2218         free(be_lun->dev_path, M_CTLBLK);
2219         be_lun->dev_path = strdup(value, M_CTLBLK);
2220
2221         flags = FREAD;
2222         value = dnvlist_get_string(cbe_lun->options, "readonly", NULL);
2223         if (value != NULL) {
2224                 if (strcmp(value, "on") != 0)
2225                         flags |= FWRITE;
2226         } else if (cbe_lun->lun_type == T_DIRECT)
2227                 flags |= FWRITE;
2228
2229 again:
2230         NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, be_lun->dev_path);
2231         error = vn_open(&nd, &flags, 0, NULL);
2232         if ((error == EROFS || error == EACCES) && (flags & FWRITE)) {
2233                 flags &= ~FWRITE;
2234                 goto again;
2235         }
2236         if (error) {
2237                 /*
2238                  * This is the only reasonable guess we can make as far as
2239                  * path if the user doesn't give us a fully qualified path.
2240                  * If they want to specify a file, they need to specify the
2241                  * full path.
2242                  */
2243                 if (be_lun->dev_path[0] != '/') {
2244                         char *dev_name;
2245
2246                         asprintf(&dev_name, M_CTLBLK, "/dev/%s",
2247                                 be_lun->dev_path);
2248                         free(be_lun->dev_path, M_CTLBLK);
2249                         be_lun->dev_path = dev_name;
2250                         goto again;
2251                 }
2252                 snprintf(req->error_str, sizeof(req->error_str),
2253                     "error opening %s: %d", be_lun->dev_path, error);
2254                 return (error);
2255         }
2256         if (flags & FWRITE)
2257                 cbe_lun->flags &= ~CTL_LUN_FLAG_READONLY;
2258         else
2259                 cbe_lun->flags |= CTL_LUN_FLAG_READONLY;
2260
2261         NDFREE_PNBUF(&nd);
2262         be_lun->vn = nd.ni_vp;
2263
2264         /* We only support disks and files. */
2265         if (vn_isdisk_error(be_lun->vn, &error)) {
2266                 error = ctl_be_block_open_dev(be_lun, req);
2267         } else if (be_lun->vn->v_type == VREG) {
2268                 error = ctl_be_block_open_file(be_lun, req);
2269         } else {
2270                 error = EINVAL;
2271                 snprintf(req->error_str, sizeof(req->error_str),
2272                          "%s is not a disk or plain file", be_lun->dev_path);
2273         }
2274         VOP_UNLOCK(be_lun->vn);
2275
2276         if (error != 0)
2277                 ctl_be_block_close(be_lun);
2278         cbe_lun->serseq = CTL_LUN_SERSEQ_OFF;
2279         if (be_lun->dispatch != ctl_be_block_dispatch_dev)
2280                 cbe_lun->serseq = CTL_LUN_SERSEQ_SOFT;
2281         value = dnvlist_get_string(cbe_lun->options, "serseq", NULL);
2282         if (value != NULL && strcmp(value, "on") == 0)
2283                 cbe_lun->serseq = CTL_LUN_SERSEQ_ON;
2284         else if (value != NULL && strcmp(value, "read") == 0)
2285                 cbe_lun->serseq = CTL_LUN_SERSEQ_READ;
2286         else if (value != NULL && strcmp(value, "soft") == 0)
2287                 cbe_lun->serseq = CTL_LUN_SERSEQ_SOFT;
2288         else if (value != NULL && strcmp(value, "off") == 0)
2289                 cbe_lun->serseq = CTL_LUN_SERSEQ_OFF;
2290         return (0);
2291 }
2292
2293 static int
2294 ctl_be_block_create(struct ctl_be_block_softc *softc, struct ctl_lun_req *req)
2295 {
2296         struct ctl_be_lun *cbe_lun;
2297         struct ctl_be_block_lun *be_lun;
2298         struct ctl_lun_create_params *params;
2299         char num_thread_str[16];
2300         char tmpstr[32];
2301         const char *value;
2302         int retval, num_threads;
2303         int tmp_num_threads;
2304
2305         params = &req->reqdata.create;
2306         retval = 0;
2307         req->status = CTL_LUN_OK;
2308
2309         be_lun = malloc(sizeof(*be_lun), M_CTLBLK, M_ZERO | M_WAITOK);
2310         cbe_lun = &be_lun->cbe_lun;
2311         be_lun->params = req->reqdata.create;
2312         be_lun->softc = softc;
2313         STAILQ_INIT(&be_lun->input_queue);
2314         STAILQ_INIT(&be_lun->config_read_queue);
2315         STAILQ_INIT(&be_lun->config_write_queue);
2316         STAILQ_INIT(&be_lun->datamove_queue);
2317         mtx_init(&be_lun->io_lock, "ctlblock io", NULL, MTX_DEF);
2318         mtx_init(&be_lun->queue_lock, "ctlblock queue", NULL, MTX_DEF);
2319         cbe_lun->options = nvlist_clone(req->args_nvl);
2320
2321         if (params->flags & CTL_LUN_FLAG_DEV_TYPE)
2322                 cbe_lun->lun_type = params->device_type;
2323         else
2324                 cbe_lun->lun_type = T_DIRECT;
2325         be_lun->flags = 0;
2326         cbe_lun->flags = 0;
2327         value = dnvlist_get_string(cbe_lun->options, "ha_role", NULL);
2328         if (value != NULL) {
2329                 if (strcmp(value, "primary") == 0)
2330                         cbe_lun->flags |= CTL_LUN_FLAG_PRIMARY;
2331         } else if (control_softc->flags & CTL_FLAG_ACTIVE_SHELF)
2332                 cbe_lun->flags |= CTL_LUN_FLAG_PRIMARY;
2333
2334         if (cbe_lun->lun_type == T_DIRECT ||
2335             cbe_lun->lun_type == T_CDROM) {
2336                 be_lun->size_bytes = params->lun_size_bytes;
2337                 if (params->blocksize_bytes != 0)
2338                         cbe_lun->blocksize = params->blocksize_bytes;
2339                 else if (cbe_lun->lun_type == T_CDROM)
2340                         cbe_lun->blocksize = 2048;
2341                 else
2342                         cbe_lun->blocksize = 512;
2343                 be_lun->size_blocks = be_lun->size_bytes / cbe_lun->blocksize;
2344                 cbe_lun->maxlba = (be_lun->size_blocks == 0) ?
2345                     0 : (be_lun->size_blocks - 1);
2346
2347                 if ((cbe_lun->flags & CTL_LUN_FLAG_PRIMARY) ||
2348                     control_softc->ha_mode == CTL_HA_MODE_SER_ONLY) {
2349                         retval = ctl_be_block_open(be_lun, req);
2350                         if (retval != 0) {
2351                                 retval = 0;
2352                                 req->status = CTL_LUN_WARNING;
2353                         }
2354                 }
2355                 num_threads = cbb_num_threads;
2356         } else {
2357                 num_threads = 1;
2358         }
2359
2360         value = dnvlist_get_string(cbe_lun->options, "num_threads", NULL);
2361         if (value != NULL) {
2362                 tmp_num_threads = strtol(value, NULL, 0);
2363
2364                 /*
2365                  * We don't let the user specify less than one
2366                  * thread, but hope he's clueful enough not to
2367                  * specify 1000 threads.
2368                  */
2369                 if (tmp_num_threads < 1) {
2370                         snprintf(req->error_str, sizeof(req->error_str),
2371                                  "invalid number of threads %s",
2372                                  num_thread_str);
2373                         goto bailout_error;
2374                 }
2375                 num_threads = tmp_num_threads;
2376         }
2377
2378         if (be_lun->vn == NULL)
2379                 cbe_lun->flags |= CTL_LUN_FLAG_NO_MEDIA;
2380         /* Tell the user the blocksize we ended up using */
2381         params->lun_size_bytes = be_lun->size_bytes;
2382         params->blocksize_bytes = cbe_lun->blocksize;
2383         if (params->flags & CTL_LUN_FLAG_ID_REQ) {
2384                 cbe_lun->req_lun_id = params->req_lun_id;
2385                 cbe_lun->flags |= CTL_LUN_FLAG_ID_REQ;
2386         } else
2387                 cbe_lun->req_lun_id = 0;
2388
2389         cbe_lun->lun_shutdown = ctl_be_block_lun_shutdown;
2390         cbe_lun->be = &ctl_be_block_driver;
2391
2392         if ((params->flags & CTL_LUN_FLAG_SERIAL_NUM) == 0) {
2393                 snprintf(tmpstr, sizeof(tmpstr), "MYSERIAL%04d",
2394                          softc->num_luns);
2395                 strncpy((char *)cbe_lun->serial_num, tmpstr,
2396                         MIN(sizeof(cbe_lun->serial_num), sizeof(tmpstr)));
2397
2398                 /* Tell the user what we used for a serial number */
2399                 strncpy((char *)params->serial_num, tmpstr,
2400                         MIN(sizeof(params->serial_num), sizeof(tmpstr)));
2401         } else {
2402                 strncpy((char *)cbe_lun->serial_num, params->serial_num,
2403                         MIN(sizeof(cbe_lun->serial_num),
2404                         sizeof(params->serial_num)));
2405         }
2406         if ((params->flags & CTL_LUN_FLAG_DEVID) == 0) {
2407                 snprintf(tmpstr, sizeof(tmpstr), "MYDEVID%04d", softc->num_luns);
2408                 strncpy((char *)cbe_lun->device_id, tmpstr,
2409                         MIN(sizeof(cbe_lun->device_id), sizeof(tmpstr)));
2410
2411                 /* Tell the user what we used for a device ID */
2412                 strncpy((char *)params->device_id, tmpstr,
2413                         MIN(sizeof(params->device_id), sizeof(tmpstr)));
2414         } else {
2415                 strncpy((char *)cbe_lun->device_id, params->device_id,
2416                         MIN(sizeof(cbe_lun->device_id),
2417                             sizeof(params->device_id)));
2418         }
2419
2420         TASK_INIT(&be_lun->io_task, /*priority*/0, ctl_be_block_worker, be_lun);
2421
2422         be_lun->io_taskqueue = taskqueue_create("ctlblocktq", M_WAITOK,
2423             taskqueue_thread_enqueue, /*context*/&be_lun->io_taskqueue);
2424
2425         if (be_lun->io_taskqueue == NULL) {
2426                 snprintf(req->error_str, sizeof(req->error_str),
2427                          "unable to create taskqueue");
2428                 goto bailout_error;
2429         }
2430
2431         /*
2432          * Note that we start the same number of threads by default for
2433          * both the file case and the block device case.  For the file
2434          * case, we need multiple threads to allow concurrency, because the
2435          * vnode interface is designed to be a blocking interface.  For the
2436          * block device case, ZFS zvols at least will block the caller's
2437          * context in many instances, and so we need multiple threads to
2438          * overcome that problem.  Other block devices don't need as many
2439          * threads, but they shouldn't cause too many problems.
2440          *
2441          * If the user wants to just have a single thread for a block
2442          * device, he can specify that when the LUN is created, or change
2443          * the tunable/sysctl to alter the default number of threads.
2444          */
2445         retval = taskqueue_start_threads_in_proc(&be_lun->io_taskqueue,
2446                                          /*num threads*/num_threads,
2447                                          /*priority*/PUSER,
2448                                          /*proc*/control_softc->ctl_proc,
2449                                          /*thread name*/"block");
2450
2451         if (retval != 0)
2452                 goto bailout_error;
2453
2454         be_lun->num_threads = num_threads;
2455
2456         retval = ctl_add_lun(&be_lun->cbe_lun);
2457         if (retval != 0) {
2458                 snprintf(req->error_str, sizeof(req->error_str),
2459                          "ctl_add_lun() returned error %d, see dmesg for "
2460                          "details", retval);
2461                 retval = 0;
2462                 goto bailout_error;
2463         }
2464
2465         be_lun->disk_stats = devstat_new_entry("cbb", cbe_lun->lun_id,
2466                                                cbe_lun->blocksize,
2467                                                DEVSTAT_ALL_SUPPORTED,
2468                                                cbe_lun->lun_type
2469                                                | DEVSTAT_TYPE_IF_OTHER,
2470                                                DEVSTAT_PRIORITY_OTHER);
2471
2472         mtx_lock(&softc->lock);
2473         softc->num_luns++;
2474         SLIST_INSERT_HEAD(&softc->lun_list, be_lun, links);
2475         mtx_unlock(&softc->lock);
2476
2477         params->req_lun_id = cbe_lun->lun_id;
2478
2479         return (retval);
2480
2481 bailout_error:
2482         req->status = CTL_LUN_ERROR;
2483
2484         if (be_lun->io_taskqueue != NULL)
2485                 taskqueue_free(be_lun->io_taskqueue);
2486         ctl_be_block_close(be_lun);
2487         if (be_lun->dev_path != NULL)
2488                 free(be_lun->dev_path, M_CTLBLK);
2489         nvlist_destroy(cbe_lun->options);
2490         mtx_destroy(&be_lun->queue_lock);
2491         mtx_destroy(&be_lun->io_lock);
2492         free(be_lun, M_CTLBLK);
2493
2494         return (retval);
2495 }
2496
2497 static int
2498 ctl_be_block_rm(struct ctl_be_block_softc *softc, struct ctl_lun_req *req)
2499 {
2500         struct ctl_lun_rm_params *params;
2501         struct ctl_be_block_lun *be_lun;
2502         struct ctl_be_lun *cbe_lun;
2503         int retval;
2504
2505         params = &req->reqdata.rm;
2506
2507         sx_xlock(&softc->modify_lock);
2508         mtx_lock(&softc->lock);
2509         SLIST_FOREACH(be_lun, &softc->lun_list, links) {
2510                 if (be_lun->cbe_lun.lun_id == params->lun_id) {
2511                         SLIST_REMOVE(&softc->lun_list, be_lun,
2512                             ctl_be_block_lun, links);
2513                         softc->num_luns--;
2514                         break;
2515                 }
2516         }
2517         mtx_unlock(&softc->lock);
2518         sx_xunlock(&softc->modify_lock);
2519         if (be_lun == NULL) {
2520                 snprintf(req->error_str, sizeof(req->error_str),
2521                          "LUN %u is not managed by the block backend",
2522                          params->lun_id);
2523                 goto bailout_error;
2524         }
2525         cbe_lun = &be_lun->cbe_lun;
2526
2527         if (be_lun->vn != NULL) {
2528                 cbe_lun->flags |= CTL_LUN_FLAG_NO_MEDIA;
2529                 ctl_lun_no_media(cbe_lun);
2530                 taskqueue_drain_all(be_lun->io_taskqueue);
2531                 ctl_be_block_close(be_lun);
2532         }
2533
2534         mtx_lock(&softc->lock);
2535         be_lun->flags |= CTL_BE_BLOCK_LUN_WAITING;
2536         mtx_unlock(&softc->lock);
2537
2538         retval = ctl_remove_lun(cbe_lun);
2539         if (retval != 0) {
2540                 snprintf(req->error_str, sizeof(req->error_str),
2541                          "error %d returned from ctl_remove_lun() for "
2542                          "LUN %d", retval, params->lun_id);
2543                 mtx_lock(&softc->lock);
2544                 be_lun->flags &= ~CTL_BE_BLOCK_LUN_WAITING;
2545                 mtx_unlock(&softc->lock);
2546                 goto bailout_error;
2547         }
2548
2549         mtx_lock(&softc->lock);
2550         while ((be_lun->flags & CTL_BE_BLOCK_LUN_UNCONFIGURED) == 0) {
2551                 retval = msleep(be_lun, &softc->lock, PCATCH, "ctlblockrm", 0);
2552                 if (retval == EINTR)
2553                         break;
2554         }
2555         be_lun->flags &= ~CTL_BE_BLOCK_LUN_WAITING;
2556         if (be_lun->flags & CTL_BE_BLOCK_LUN_UNCONFIGURED) {
2557                 mtx_unlock(&softc->lock);
2558                 free(be_lun, M_CTLBLK);
2559         } else {
2560                 mtx_unlock(&softc->lock);
2561                 return (EINTR);
2562         }
2563
2564         req->status = CTL_LUN_OK;
2565         return (0);
2566
2567 bailout_error:
2568         req->status = CTL_LUN_ERROR;
2569         return (0);
2570 }
2571
2572 static int
2573 ctl_be_block_modify(struct ctl_be_block_softc *softc, struct ctl_lun_req *req)
2574 {
2575         struct ctl_lun_modify_params *params;
2576         struct ctl_be_block_lun *be_lun;
2577         struct ctl_be_lun *cbe_lun;
2578         const char *value;
2579         uint64_t oldsize;
2580         int error, wasprim;
2581
2582         params = &req->reqdata.modify;
2583
2584         sx_xlock(&softc->modify_lock);
2585         mtx_lock(&softc->lock);
2586         SLIST_FOREACH(be_lun, &softc->lun_list, links) {
2587                 if (be_lun->cbe_lun.lun_id == params->lun_id)
2588                         break;
2589         }
2590         mtx_unlock(&softc->lock);
2591         if (be_lun == NULL) {
2592                 snprintf(req->error_str, sizeof(req->error_str),
2593                          "LUN %u is not managed by the block backend",
2594                          params->lun_id);
2595                 goto bailout_error;
2596         }
2597         cbe_lun = &be_lun->cbe_lun;
2598
2599         if (params->lun_size_bytes != 0)
2600                 be_lun->params.lun_size_bytes = params->lun_size_bytes;
2601
2602         if (req->args_nvl != NULL) {
2603                 nvlist_destroy(cbe_lun->options);
2604                 cbe_lun->options = nvlist_clone(req->args_nvl);
2605         }
2606
2607         wasprim = (cbe_lun->flags & CTL_LUN_FLAG_PRIMARY);
2608         value = dnvlist_get_string(cbe_lun->options, "ha_role", NULL);
2609         if (value != NULL) {
2610                 if (strcmp(value, "primary") == 0)
2611                         cbe_lun->flags |= CTL_LUN_FLAG_PRIMARY;
2612                 else
2613                         cbe_lun->flags &= ~CTL_LUN_FLAG_PRIMARY;
2614         } else if (control_softc->flags & CTL_FLAG_ACTIVE_SHELF)
2615                 cbe_lun->flags |= CTL_LUN_FLAG_PRIMARY;
2616         else
2617                 cbe_lun->flags &= ~CTL_LUN_FLAG_PRIMARY;
2618         if (wasprim != (cbe_lun->flags & CTL_LUN_FLAG_PRIMARY)) {
2619                 if (cbe_lun->flags & CTL_LUN_FLAG_PRIMARY)
2620                         ctl_lun_primary(cbe_lun);
2621                 else
2622                         ctl_lun_secondary(cbe_lun);
2623         }
2624
2625         oldsize = be_lun->size_blocks;
2626         if ((cbe_lun->flags & CTL_LUN_FLAG_PRIMARY) ||
2627             control_softc->ha_mode == CTL_HA_MODE_SER_ONLY) {
2628                 if (be_lun->vn == NULL)
2629                         error = ctl_be_block_open(be_lun, req);
2630                 else if (vn_isdisk_error(be_lun->vn, &error))
2631                         error = ctl_be_block_open_dev(be_lun, req);
2632                 else if (be_lun->vn->v_type == VREG) {
2633                         vn_lock(be_lun->vn, LK_SHARED | LK_RETRY);
2634                         error = ctl_be_block_open_file(be_lun, req);
2635                         VOP_UNLOCK(be_lun->vn);
2636                 } else
2637                         error = EINVAL;
2638                 if ((cbe_lun->flags & CTL_LUN_FLAG_NO_MEDIA) &&
2639                     be_lun->vn != NULL) {
2640                         cbe_lun->flags &= ~CTL_LUN_FLAG_NO_MEDIA;
2641                         ctl_lun_has_media(cbe_lun);
2642                 } else if ((cbe_lun->flags & CTL_LUN_FLAG_NO_MEDIA) == 0 &&
2643                     be_lun->vn == NULL) {
2644                         cbe_lun->flags |= CTL_LUN_FLAG_NO_MEDIA;
2645                         ctl_lun_no_media(cbe_lun);
2646                 }
2647                 cbe_lun->flags &= ~CTL_LUN_FLAG_EJECTED;
2648         } else {
2649                 if (be_lun->vn != NULL) {
2650                         cbe_lun->flags |= CTL_LUN_FLAG_NO_MEDIA;
2651                         ctl_lun_no_media(cbe_lun);
2652                         taskqueue_drain_all(be_lun->io_taskqueue);
2653                         error = ctl_be_block_close(be_lun);
2654                 } else
2655                         error = 0;
2656         }
2657         if (be_lun->size_blocks != oldsize)
2658                 ctl_lun_capacity_changed(cbe_lun);
2659
2660         /* Tell the user the exact size we ended up using */
2661         params->lun_size_bytes = be_lun->size_bytes;
2662
2663         sx_xunlock(&softc->modify_lock);
2664         req->status = error ? CTL_LUN_WARNING : CTL_LUN_OK;
2665         return (0);
2666
2667 bailout_error:
2668         sx_xunlock(&softc->modify_lock);
2669         req->status = CTL_LUN_ERROR;
2670         return (0);
2671 }
2672
2673 static void
2674 ctl_be_block_lun_shutdown(struct ctl_be_lun *cbe_lun)
2675 {
2676         struct ctl_be_block_lun *be_lun = (struct ctl_be_block_lun *)cbe_lun;
2677         struct ctl_be_block_softc *softc = be_lun->softc;
2678
2679         taskqueue_drain_all(be_lun->io_taskqueue);
2680         taskqueue_free(be_lun->io_taskqueue);
2681         if (be_lun->disk_stats != NULL)
2682                 devstat_remove_entry(be_lun->disk_stats);
2683         nvlist_destroy(be_lun->cbe_lun.options);
2684         free(be_lun->dev_path, M_CTLBLK);
2685         mtx_destroy(&be_lun->queue_lock);
2686         mtx_destroy(&be_lun->io_lock);
2687
2688         mtx_lock(&softc->lock);
2689         be_lun->flags |= CTL_BE_BLOCK_LUN_UNCONFIGURED;
2690         if (be_lun->flags & CTL_BE_BLOCK_LUN_WAITING)
2691                 wakeup(be_lun);
2692         else
2693                 free(be_lun, M_CTLBLK);
2694         mtx_unlock(&softc->lock);
2695 }
2696
2697 static int
2698 ctl_be_block_config_write(union ctl_io *io)
2699 {
2700         struct ctl_be_block_lun *be_lun;
2701         struct ctl_be_lun *cbe_lun;
2702         int retval;
2703
2704         DPRINTF("entered\n");
2705
2706         cbe_lun = CTL_BACKEND_LUN(io);
2707         be_lun = (struct ctl_be_block_lun *)cbe_lun;
2708
2709         retval = 0;
2710         switch (io->scsiio.cdb[0]) {
2711         case SYNCHRONIZE_CACHE:
2712         case SYNCHRONIZE_CACHE_16:
2713         case WRITE_SAME_10:
2714         case WRITE_SAME_16:
2715         case UNMAP:
2716                 /*
2717                  * The upper level CTL code will filter out any CDBs with
2718                  * the immediate bit set and return the proper error.
2719                  *
2720                  * We don't really need to worry about what LBA range the
2721                  * user asked to be synced out.  When they issue a sync
2722                  * cache command, we'll sync out the whole thing.
2723                  */
2724                 mtx_lock(&be_lun->queue_lock);
2725                 STAILQ_INSERT_TAIL(&be_lun->config_write_queue, &io->io_hdr,
2726                                    links);
2727                 mtx_unlock(&be_lun->queue_lock);
2728                 taskqueue_enqueue(be_lun->io_taskqueue, &be_lun->io_task);
2729                 break;
2730         case START_STOP_UNIT: {
2731                 struct scsi_start_stop_unit *cdb;
2732                 struct ctl_lun_req req;
2733
2734                 cdb = (struct scsi_start_stop_unit *)io->scsiio.cdb;
2735                 if ((cdb->how & SSS_PC_MASK) != 0) {
2736                         ctl_set_success(&io->scsiio);
2737                         ctl_config_write_done(io);
2738                         break;
2739                 }
2740                 if (cdb->how & SSS_START) {
2741                         if ((cdb->how & SSS_LOEJ) && be_lun->vn == NULL) {
2742                                 retval = ctl_be_block_open(be_lun, &req);
2743                                 cbe_lun->flags &= ~CTL_LUN_FLAG_EJECTED;
2744                                 if (retval == 0) {
2745                                         cbe_lun->flags &= ~CTL_LUN_FLAG_NO_MEDIA;
2746                                         ctl_lun_has_media(cbe_lun);
2747                                 } else {
2748                                         cbe_lun->flags |= CTL_LUN_FLAG_NO_MEDIA;
2749                                         ctl_lun_no_media(cbe_lun);
2750                                 }
2751                         }
2752                         ctl_start_lun(cbe_lun);
2753                 } else {
2754                         ctl_stop_lun(cbe_lun);
2755                         if (cdb->how & SSS_LOEJ) {
2756                                 cbe_lun->flags |= CTL_LUN_FLAG_NO_MEDIA;
2757                                 cbe_lun->flags |= CTL_LUN_FLAG_EJECTED;
2758                                 ctl_lun_ejected(cbe_lun);
2759                                 if (be_lun->vn != NULL)
2760                                         ctl_be_block_close(be_lun);
2761                         }
2762                 }
2763
2764                 ctl_set_success(&io->scsiio);
2765                 ctl_config_write_done(io);
2766                 break;
2767         }
2768         case PREVENT_ALLOW:
2769                 ctl_set_success(&io->scsiio);
2770                 ctl_config_write_done(io);
2771                 break;
2772         default:
2773                 ctl_set_invalid_opcode(&io->scsiio);
2774                 ctl_config_write_done(io);
2775                 retval = CTL_RETVAL_COMPLETE;
2776                 break;
2777         }
2778
2779         return (retval);
2780 }
2781
2782 static int
2783 ctl_be_block_config_read(union ctl_io *io)
2784 {
2785         struct ctl_be_block_lun *be_lun;
2786         int retval = 0;
2787
2788         DPRINTF("entered\n");
2789
2790         be_lun = (struct ctl_be_block_lun *)CTL_BACKEND_LUN(io);
2791
2792         switch (io->scsiio.cdb[0]) {
2793         case SERVICE_ACTION_IN:
2794                 if (io->scsiio.cdb[1] == SGLS_SERVICE_ACTION) {
2795                         mtx_lock(&be_lun->queue_lock);
2796                         STAILQ_INSERT_TAIL(&be_lun->config_read_queue,
2797                             &io->io_hdr, links);
2798                         mtx_unlock(&be_lun->queue_lock);
2799                         taskqueue_enqueue(be_lun->io_taskqueue,
2800                             &be_lun->io_task);
2801                         retval = CTL_RETVAL_QUEUED;
2802                         break;
2803                 }
2804                 ctl_set_invalid_field(&io->scsiio,
2805                                       /*sks_valid*/ 1,
2806                                       /*command*/ 1,
2807                                       /*field*/ 1,
2808                                       /*bit_valid*/ 1,
2809                                       /*bit*/ 4);
2810                 ctl_config_read_done(io);
2811                 retval = CTL_RETVAL_COMPLETE;
2812                 break;
2813         default:
2814                 ctl_set_invalid_opcode(&io->scsiio);
2815                 ctl_config_read_done(io);
2816                 retval = CTL_RETVAL_COMPLETE;
2817                 break;
2818         }
2819
2820         return (retval);
2821 }
2822
2823 static int
2824 ctl_be_block_lun_info(struct ctl_be_lun *cbe_lun, struct sbuf *sb)
2825 {
2826         struct ctl_be_block_lun *lun = (struct ctl_be_block_lun *)cbe_lun;
2827         int retval;
2828
2829         retval = sbuf_cat(sb, "\t<num_threads>");
2830         if (retval != 0)
2831                 goto bailout;
2832         retval = sbuf_printf(sb, "%d", lun->num_threads);
2833         if (retval != 0)
2834                 goto bailout;
2835         retval = sbuf_cat(sb, "</num_threads>\n");
2836
2837 bailout:
2838         return (retval);
2839 }
2840
2841 static uint64_t
2842 ctl_be_block_lun_attr(struct ctl_be_lun *cbe_lun, const char *attrname)
2843 {
2844         struct ctl_be_block_lun *lun = (struct ctl_be_block_lun *)cbe_lun;
2845
2846         if (lun->getattr == NULL)
2847                 return (UINT64_MAX);
2848         return (lun->getattr(lun, attrname));
2849 }
2850
2851 static int
2852 ctl_be_block_init(void)
2853 {
2854         struct ctl_be_block_softc *softc = &backend_block_softc;
2855
2856         sx_init(&softc->modify_lock, "ctlblock modify");
2857         mtx_init(&softc->lock, "ctlblock", NULL, MTX_DEF);
2858         softc->beio_zone = uma_zcreate("beio", sizeof(struct ctl_be_block_io),
2859             NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
2860         softc->bufmin_zone = uma_zcreate("ctlblockmin", CTLBLK_MIN_SEG,
2861             NULL, NULL, NULL, NULL, /*align*/ 0, /*flags*/0);
2862         if (CTLBLK_MIN_SEG < CTLBLK_MAX_SEG)
2863                 softc->bufmax_zone = uma_zcreate("ctlblockmax", CTLBLK_MAX_SEG,
2864                     NULL, NULL, NULL, NULL, /*align*/ 0, /*flags*/0);
2865         SLIST_INIT(&softc->lun_list);
2866         return (0);
2867 }
2868
2869 static int
2870 ctl_be_block_shutdown(void)
2871 {
2872         struct ctl_be_block_softc *softc = &backend_block_softc;
2873         struct ctl_be_block_lun *lun;
2874
2875         mtx_lock(&softc->lock);
2876         while ((lun = SLIST_FIRST(&softc->lun_list)) != NULL) {
2877                 SLIST_REMOVE_HEAD(&softc->lun_list, links);
2878                 softc->num_luns--;
2879                 /*
2880                  * Drop our lock here.  Since ctl_remove_lun() can call
2881                  * back into us, this could potentially lead to a recursive
2882                  * lock of the same mutex, which would cause a hang.
2883                  */
2884                 mtx_unlock(&softc->lock);
2885                 ctl_remove_lun(&lun->cbe_lun);
2886                 mtx_lock(&softc->lock);
2887         }
2888         mtx_unlock(&softc->lock);
2889         uma_zdestroy(softc->bufmin_zone);
2890         if (CTLBLK_MIN_SEG < CTLBLK_MAX_SEG)
2891                 uma_zdestroy(softc->bufmax_zone);
2892         uma_zdestroy(softc->beio_zone);
2893         mtx_destroy(&softc->lock);
2894         sx_destroy(&softc->modify_lock);
2895         return (0);
2896 }