sys/cam/scsi/scsi_targ_bh.c

   1 /*-
   2  * Implementation of the Target Mode 'Black Hole device' for CAM.
   3  *
   4  * Copyright (c) 1999 Justin T. Gibbs.
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions, and the following disclaimer,
  12  *    without modification, immediately at the beginning of the file.
  13  * 2. The name of the author may not be used to endorse or promote products
  14  *    derived from this software without specific prior written permission.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  19  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
  20  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  26  * SUCH DAMAGE.
  27  */
  28
  29 #include <sys/cdefs.h>
  30 __FBSDID("$FreeBSD$");
  31
  32 #include <sys/param.h>
  33 #include <sys/queue.h>
  34 #include <sys/systm.h>
  35 #include <sys/kernel.h>
  36 #include <sys/types.h>
  37 #include <sys/bio.h>
  38 #include <sys/conf.h>
  39 #include <sys/devicestat.h>
  40 #include <sys/malloc.h>
  41 #include <sys/uio.h>
  42
  43 #include <cam/cam.h>
  44 #include <cam/cam_ccb.h>
  45 #include <cam/cam_periph.h>
  46 #include <cam/cam_queue.h>
  47 #include <cam/cam_xpt_periph.h>
  48 #include <cam/cam_debug.h>
  49 #include <cam/cam_sim.h>
  50
  51 #include <cam/scsi/scsi_all.h>
  52 #include <cam/scsi/scsi_message.h>
  53
  54 static MALLOC_DEFINE(M_SCSIBH, "SCSI bh", "SCSI blackhole buffers");
  55
  56 typedef enum {
  57         TARGBH_STATE_NORMAL,
  58         TARGBH_STATE_EXCEPTION,
  59         TARGBH_STATE_TEARDOWN
  60 } targbh_state;
  61
  62 typedef enum {
  63         TARGBH_FLAG_NONE         = 0x00,
  64         TARGBH_FLAG_LUN_ENABLED  = 0x01
  65 } targbh_flags;
  66
  67 typedef enum {
  68         TARGBH_CCB_WORKQ
  69 } targbh_ccb_types;
  70
  71 #define MAX_ACCEPT      8
  72 #define MAX_IMMEDIATE   16
  73 #define MAX_BUF_SIZE    256     /* Max inquiry/sense/mode page transfer */
  74
  75 /* Offsets into our private CCB area for storing accept information */
  76 #define ccb_type        ppriv_field0
  77 #define ccb_descr       ppriv_ptr1
  78
  79 /* We stick a pointer to the originating accept TIO in each continue I/O CCB */
  80 #define ccb_atio        ppriv_ptr1
  81
  82 TAILQ_HEAD(ccb_queue, ccb_hdr);
  83
  84 struct targbh_softc {
  85         struct          ccb_queue pending_queue;
  86         struct          ccb_queue work_queue;
  87         struct          ccb_queue unknown_atio_queue;
  88         struct          devstat device_stats;
  89         targbh_state    state;
  90         targbh_flags    flags;
  91         u_int           init_level;
  92         u_int           inq_data_len;
  93         struct          ccb_accept_tio *accept_tio_list;
  94         struct          ccb_hdr_slist immed_notify_slist;
  95 };
  96
  97 struct targbh_cmd_desc {
  98         struct    ccb_accept_tio* atio_link;
  99         u_int     data_resid;   /* How much left to transfer */
 100         u_int     data_increment;/* Amount to send before next disconnect */
 101         void*     data;         /* The data. Can be from backing_store or not */
 102         void*     backing_store;/* Backing store allocated for this descriptor*/
 103         u_int     max_size;     /* Size of backing_store */
 104         u_int32_t timeout;
 105         u_int8_t  status;       /* Status to return to initiator */
 106 };
 107
 108 static struct scsi_inquiry_data no_lun_inq_data =
 109 {
 110         T_NODEVICE | (SID_QUAL_BAD_LU << 5), 0,
 111         /* version */2, /* format version */2
 112 };
 113
 114 static struct scsi_sense_data_fixed no_lun_sense_data =
 115 {
 116         SSD_CURRENT_ERROR|SSD_ERRCODE_VALID,
 117         0,
 118         SSD_KEY_NOT_READY,
 119         { 0, 0, 0, 0 },
 120         /*extra_len*/offsetof(struct scsi_sense_data_fixed, fru)
 121                    - offsetof(struct scsi_sense_data_fixed, extra_len),
 122         { 0, 0, 0, 0 },
 123         /* Logical Unit Not Supported */
 124         /*ASC*/0x25, /*ASCQ*/0
 125 };
 126
 127 static const int request_sense_size = offsetof(struct scsi_sense_data_fixed, fru);
 128
 129 static periph_init_t    targbhinit;
 130 static void             targbhasync(void *callback_arg, u_int32_t code,
 131                                     struct cam_path *path, void *arg);
 132 static cam_status       targbhenlun(struct cam_periph *periph);
 133 static cam_status       targbhdislun(struct cam_periph *periph);
 134 static periph_ctor_t    targbhctor;
 135 static periph_dtor_t    targbhdtor;
 136 static periph_start_t   targbhstart;
 137 static void             targbhdone(struct cam_periph *periph,
 138                                    union ccb *done_ccb);
 139 #ifdef NOTYET
 140 static  int             targbherror(union ccb *ccb, u_int32_t cam_flags,
 141                                     u_int32_t sense_flags);
 142 #endif
 143 static struct targbh_cmd_desc*  targbhallocdescr(void);
 144 static void             targbhfreedescr(struct targbh_cmd_desc *buf);
 145
 146 static struct periph_driver targbhdriver =
 147 {
 148         targbhinit, "targbh",
 149         TAILQ_HEAD_INITIALIZER(targbhdriver.units), /* generation */ 0
 150 };
 151
 152 PERIPHDRIVER_DECLARE(targbh, targbhdriver);
 153
 154 static void
 155 targbhinit(void)
 156 {
 157         cam_status status;
 158
 159         /*
 160          * Install a global async callback.  This callback will
 161          * receive async callbacks like "new path registered".
 162          */
 163         status = xpt_register_async(AC_PATH_REGISTERED | AC_PATH_DEREGISTERED,
 164                                     targbhasync, NULL, NULL);
 165
 166         if (status != CAM_REQ_CMP) {
 167                 printf("targbh: Failed to attach master async callback "
 168                        "due to status 0x%x!\n", status);
 169         }
 170 }
 171
 172 static void
 173 targbhasync(void *callback_arg, u_int32_t code,
 174             struct cam_path *path, void *arg)
 175 {
 176         struct cam_path *new_path;
 177         struct ccb_pathinq *cpi;
 178         path_id_t bus_path_id;
 179         cam_status status;
 180
 181         cpi = (struct ccb_pathinq *)arg;
 182         if (code == AC_PATH_REGISTERED)
 183                 bus_path_id = cpi->ccb_h.path_id;
 184         else
 185                 bus_path_id = xpt_path_path_id(path);
 186         /*
 187          * Allocate a peripheral instance for
 188          * this target instance.
 189          */
 190         status = xpt_create_path(&new_path, NULL,
 191                                  bus_path_id,
 192                                  CAM_TARGET_WILDCARD, CAM_LUN_WILDCARD);
 193         if (status != CAM_REQ_CMP) {
 194                 printf("targbhasync: Unable to create path "
 195                         "due to status 0x%x\n", status);
 196                 return;
 197         }
 198
 199         switch (code) {
 200         case AC_PATH_REGISTERED:
 201         {
 202                 /* Only attach to controllers that support target mode */
 203                 if ((cpi->target_sprt & PIT_PROCESSOR) == 0)
 204                         break;
 205
 206                 status = cam_periph_alloc(targbhctor, NULL, targbhdtor,
 207                                           targbhstart,
 208                                           "targbh", CAM_PERIPH_BIO,
 209                                           new_path, targbhasync,
 210                                           AC_PATH_REGISTERED,
 211                                           cpi);
 212                 break;
 213         }
 214         case AC_PATH_DEREGISTERED:
 215         {
 216                 struct cam_periph *periph;
 217
 218                 if ((periph = cam_periph_find(new_path, "targbh")) != NULL)
 219                         cam_periph_invalidate(periph);
 220                 break;
 221         }
 222         default:
 223                 break;
 224         }
 225         xpt_free_path(new_path);
 226 }
 227
 228 /* Attempt to enable our lun */
 229 static cam_status
 230 targbhenlun(struct cam_periph *periph)
 231 {
 232         union ccb immed_ccb;
 233         struct targbh_softc *softc;
 234         cam_status status;
 235         int i;
 236
 237         softc = (struct targbh_softc *)periph->softc;
 238
 239         if ((softc->flags & TARGBH_FLAG_LUN_ENABLED) != 0)
 240                 return (CAM_REQ_CMP);
 241
 242         xpt_setup_ccb(&immed_ccb.ccb_h, periph->path, CAM_PRIORITY_NORMAL);
 243         immed_ccb.ccb_h.func_code = XPT_EN_LUN;
 244
 245         /* Don't need support for any vendor specific commands */
 246         immed_ccb.cel.grp6_len = 0;
 247         immed_ccb.cel.grp7_len = 0;
 248         immed_ccb.cel.enable = 1;
 249         xpt_action(&immed_ccb);
 250         status = immed_ccb.ccb_h.status;
 251         if (status != CAM_REQ_CMP) {
 252                 xpt_print(periph->path,
 253                     "targbhenlun - Enable Lun Rejected with status 0x%x\n",
 254                     status);
 255                 return (status);
 256         }
 257
 258         softc->flags |= TARGBH_FLAG_LUN_ENABLED;
 259
 260         /*
 261          * Build up a buffer of accept target I/O
 262          * operations for incoming selections.
 263          */
 264         for (i = 0; i < MAX_ACCEPT; i++) {
 265                 struct ccb_accept_tio *atio;
 266
 267                 atio = (struct ccb_accept_tio*)malloc(sizeof(*atio), M_SCSIBH,
 268                                                       M_NOWAIT);
 269                 if (atio == NULL) {
 270                         status = CAM_RESRC_UNAVAIL;
 271                         break;
 272                 }
 273
 274                 atio->ccb_h.ccb_descr = targbhallocdescr();
 275
 276                 if (atio->ccb_h.ccb_descr == NULL) {
 277                         free(atio, M_SCSIBH);
 278                         status = CAM_RESRC_UNAVAIL;
 279                         break;
 280                 }
 281
 282                 xpt_setup_ccb(&atio->ccb_h, periph->path, CAM_PRIORITY_NORMAL);
 283                 atio->ccb_h.func_code = XPT_ACCEPT_TARGET_IO;
 284                 atio->ccb_h.cbfcnp = targbhdone;
 285                 ((struct targbh_cmd_desc*)atio->ccb_h.ccb_descr)->atio_link =
 286                     softc->accept_tio_list;
 287                 softc->accept_tio_list = atio;
 288                 xpt_action((union ccb *)atio);
 289                 status = atio->ccb_h.status;
 290                 if (status != CAM_REQ_INPROG)
 291                         break;
 292         }
 293
 294         if (i == 0) {
 295                 xpt_print(periph->path,
 296                     "targbhenlun - Could not allocate accept tio CCBs: status "
 297                     "= 0x%x\n", status);
 298                 targbhdislun(periph);
 299                 return (CAM_REQ_CMP_ERR);
 300         }
 301
 302         /*
 303          * Build up a buffer of immediate notify CCBs
 304          * so the SIM can tell us of asynchronous target mode events.
 305          */
 306         for (i = 0; i < MAX_ACCEPT; i++) {
 307                 struct ccb_immediate_notify *inot;
 308
 309                 inot = (struct ccb_immediate_notify*)malloc(sizeof(*inot),
 310                             M_SCSIBH, M_NOWAIT);
 311
 312                 if (inot == NULL) {
 313                         status = CAM_RESRC_UNAVAIL;
 314                         break;
 315                 }
 316
 317                 xpt_setup_ccb(&inot->ccb_h, periph->path, CAM_PRIORITY_NORMAL);
 318                 inot->ccb_h.func_code = XPT_IMMEDIATE_NOTIFY;
 319                 inot->ccb_h.cbfcnp = targbhdone;
 320                 SLIST_INSERT_HEAD(&softc->immed_notify_slist, &inot->ccb_h,
 321                                   periph_links.sle);
 322                 xpt_action((union ccb *)inot);
 323                 status = inot->ccb_h.status;
 324                 if (status != CAM_REQ_INPROG)
 325                         break;
 326         }
 327
 328         if (i == 0) {
 329                 xpt_print(periph->path,
 330                     "targbhenlun - Could not allocate immediate notify "
 331                     "CCBs: status = 0x%x\n", status);
 332                 targbhdislun(periph);
 333                 return (CAM_REQ_CMP_ERR);
 334         }
 335
 336         return (CAM_REQ_CMP);
 337 }
 338
 339 static cam_status
 340 targbhdislun(struct cam_periph *periph)
 341 {
 342         union ccb ccb;
 343         struct targbh_softc *softc;
 344         struct ccb_accept_tio* atio;
 345         struct ccb_hdr *ccb_h;
 346
 347         softc = (struct targbh_softc *)periph->softc;
 348         if ((softc->flags & TARGBH_FLAG_LUN_ENABLED) == 0)
 349                 return CAM_REQ_CMP;
 350
 351         /* XXX Block for Continue I/O completion */
 352
 353         /* Kill off all ACCECPT and IMMEDIATE CCBs */
 354         while ((atio = softc->accept_tio_list) != NULL) {
 355
 356                 softc->accept_tio_list =
 357                     ((struct targbh_cmd_desc*)atio->ccb_h.ccb_descr)->atio_link;
 358                 xpt_setup_ccb(&ccb.cab.ccb_h, periph->path, CAM_PRIORITY_NORMAL);
 359                 ccb.cab.ccb_h.func_code = XPT_ABORT;
 360                 ccb.cab.abort_ccb = (union ccb *)atio;
 361                 xpt_action(&ccb);
 362         }
 363
 364         while ((ccb_h = SLIST_FIRST(&softc->immed_notify_slist)) != NULL) {
 365                 SLIST_REMOVE_HEAD(&softc->immed_notify_slist, periph_links.sle);
 366                 xpt_setup_ccb(&ccb.cab.ccb_h, periph->path, CAM_PRIORITY_NORMAL);
 367                 ccb.cab.ccb_h.func_code = XPT_ABORT;
 368                 ccb.cab.abort_ccb = (union ccb *)ccb_h;
 369                 xpt_action(&ccb);
 370         }
 371
 372         /*
 373          * Dissable this lun.
 374          */
 375         xpt_setup_ccb(&ccb.cel.ccb_h, periph->path, CAM_PRIORITY_NORMAL);
 376         ccb.cel.ccb_h.func_code = XPT_EN_LUN;
 377         ccb.cel.enable = 0;
 378         xpt_action(&ccb);
 379
 380         if (ccb.cel.ccb_h.status != CAM_REQ_CMP)
 381                 printf("targbhdislun - Disabling lun on controller failed "
 382                        "with status 0x%x\n", ccb.cel.ccb_h.status);
 383         else
 384                 softc->flags &= ~TARGBH_FLAG_LUN_ENABLED;
 385         return (ccb.cel.ccb_h.status);
 386 }
 387
 388 static cam_status
 389 targbhctor(struct cam_periph *periph, void *arg)
 390 {
 391         struct targbh_softc *softc;
 392
 393         /* Allocate our per-instance private storage */
 394         softc = (struct targbh_softc *)malloc(sizeof(*softc),
 395                                               M_SCSIBH, M_NOWAIT);
 396         if (softc == NULL) {
 397                 printf("targctor: unable to malloc softc\n");
 398                 return (CAM_REQ_CMP_ERR);
 399         }
 400
 401         bzero(softc, sizeof(*softc));
 402         TAILQ_INIT(&softc->pending_queue);
 403         TAILQ_INIT(&softc->work_queue);
 404         softc->accept_tio_list = NULL;
 405         SLIST_INIT(&softc->immed_notify_slist);
 406         softc->state = TARGBH_STATE_NORMAL;
 407         periph->softc = softc;
 408         softc->init_level++;
 409
 410         if (targbhenlun(periph) != CAM_REQ_CMP)
 411                 cam_periph_invalidate(periph);
 412         return (CAM_REQ_CMP);
 413 }
 414
 415 static void
 416 targbhdtor(struct cam_periph *periph)
 417 {
 418         struct targbh_softc *softc;
 419
 420         softc = (struct targbh_softc *)periph->softc;
 421
 422         softc->state = TARGBH_STATE_TEARDOWN;
 423
 424         targbhdislun(periph);
 425
 426         switch (softc->init_level) {
 427         case 0:
 428                 panic("targdtor - impossible init level");
 429         case 1:
 430                 /* FALLTHROUGH */
 431         default:
 432                 /* XXX Wait for callback of targbhdislun() */
 433                 cam_periph_sleep(periph, softc, PRIBIO, "targbh", hz/2);
 434                 free(softc, M_SCSIBH);
 435                 break;
 436         }
 437 }
 438
 439 static void
 440 targbhstart(struct cam_periph *periph, union ccb *start_ccb)
 441 {
 442         struct targbh_softc *softc;
 443         struct ccb_hdr *ccbh;
 444         struct ccb_accept_tio *atio;
 445         struct targbh_cmd_desc *desc;
 446         struct ccb_scsiio *csio;
 447         ccb_flags flags;
 448
 449         softc = (struct targbh_softc *)periph->softc;
 450
 451         ccbh = TAILQ_FIRST(&softc->work_queue);
 452         if (ccbh == NULL) {
 453                 xpt_release_ccb(start_ccb);
 454         } else {
 455                 TAILQ_REMOVE(&softc->work_queue, ccbh, periph_links.tqe);
 456                 TAILQ_INSERT_HEAD(&softc->pending_queue, ccbh,
 457                                   periph_links.tqe);
 458                 atio = (struct ccb_accept_tio*)ccbh;
 459                 desc = (struct targbh_cmd_desc *)atio->ccb_h.ccb_descr;
 460
 461                 /* Is this a tagged request? */
 462                 flags = atio->ccb_h.flags &
 463                     (CAM_DIS_DISCONNECT|CAM_TAG_ACTION_VALID|CAM_DIR_MASK);
 464
 465                 csio = &start_ccb->csio;
 466                 /*
 467                  * If we are done with the transaction, tell the
 468                  * controller to send status and perform a CMD_CMPLT.
 469                  * If we have associated sense data, see if we can
 470                  * send that too.
 471                  */
 472                 if (desc->data_resid == desc->data_increment) {
 473                         flags |= CAM_SEND_STATUS;
 474                         if (atio->sense_len) {
 475                                 csio->sense_len = atio->sense_len;
 476                                 csio->sense_data = atio->sense_data;
 477                                 flags |= CAM_SEND_SENSE;
 478                         }
 479
 480                 }
 481
 482                 cam_fill_ctio(csio,
 483                               /*retries*/2,
 484                               targbhdone,
 485                               flags,
 486                               (flags & CAM_TAG_ACTION_VALID)?
 487                                 MSG_SIMPLE_Q_TAG : 0,
 488                               atio->tag_id,
 489                               atio->init_id,
 490                               desc->status,
 491                               /*data_ptr*/desc->data_increment == 0
 492                                           ? NULL : desc->data,
 493                               /*dxfer_len*/desc->data_increment,
 494                               /*timeout*/desc->timeout);
 495
 496                 /* Override our wildcard attachment */
 497                 start_ccb->ccb_h.target_id = atio->ccb_h.target_id;
 498                 start_ccb->ccb_h.target_lun = atio->ccb_h.target_lun;
 499
 500                 start_ccb->ccb_h.ccb_type = TARGBH_CCB_WORKQ;
 501                 start_ccb->ccb_h.ccb_atio = atio;
 502                 CAM_DEBUG(periph->path, CAM_DEBUG_SUBTRACE,
 503                           ("Sending a CTIO\n"));
 504                 xpt_action(start_ccb);
 505                 /*
 506                  * If the queue was frozen waiting for the response
 507                  * to this ATIO (for instance disconnection was disallowed),
 508                  * then release it now that our response has been queued.
 509                  */
 510                 if ((atio->ccb_h.status & CAM_DEV_QFRZN) != 0) {
 511                         cam_release_devq(periph->path,
 512                                          /*relsim_flags*/0,
 513                                          /*reduction*/0,
 514                                          /*timeout*/0,
 515                                          /*getcount_only*/0);
 516                         atio->ccb_h.status &= ~CAM_DEV_QFRZN;
 517                 }
 518                 ccbh = TAILQ_FIRST(&softc->work_queue);
 519         }
 520         if (ccbh != NULL)
 521                 xpt_schedule(periph, CAM_PRIORITY_NORMAL);
 522 }
 523
 524 static void
 525 targbhdone(struct cam_periph *periph, union ccb *done_ccb)
 526 {
 527         struct targbh_softc *softc;
 528
 529         softc = (struct targbh_softc *)periph->softc;
 530
 531         switch (done_ccb->ccb_h.func_code) {
 532         case XPT_ACCEPT_TARGET_IO:
 533         {
 534                 struct ccb_accept_tio *atio;
 535                 struct targbh_cmd_desc *descr;
 536                 u_int8_t *cdb;
 537                 int priority;
 538
 539                 atio = &done_ccb->atio;
 540                 descr = (struct targbh_cmd_desc*)atio->ccb_h.ccb_descr;
 541                 cdb = atio->cdb_io.cdb_bytes;
 542                 if (softc->state == TARGBH_STATE_TEARDOWN
 543                  || atio->ccb_h.status == CAM_REQ_ABORTED) {
 544                         targbhfreedescr(descr);
 545                         xpt_free_ccb(done_ccb);
 546                         return;
 547                 }
 548
 549                 /*
 550                  * Determine the type of incoming command and
 551                  * setup our buffer for a response.
 552                  */
 553                 switch (cdb[0]) {
 554                 case INQUIRY:
 555                 {
 556                         struct scsi_inquiry *inq;
 557
 558                         inq = (struct scsi_inquiry *)cdb;
 559                         CAM_DEBUG(periph->path, CAM_DEBUG_SUBTRACE,
 560                                   ("Saw an inquiry!\n"));
 561                         /*
 562                          * Validate the command.  We don't
 563                          * support any VPD pages, so complain
 564                          * if EVPD is set.
 565                          */
 566                         if ((inq->byte2 & SI_EVPD) != 0
 567                          || inq->page_code != 0) {
 568                                 atio->ccb_h.flags &= ~CAM_DIR_MASK;
 569                                 atio->ccb_h.flags |= CAM_DIR_NONE;
 570                                 /*
 571                                  * This needs to have other than a
 572                                  * no_lun_sense_data response.
 573                                  */
 574                                 bcopy(&no_lun_sense_data, &atio->sense_data,
 575                                       min(sizeof(no_lun_sense_data),
 576                                           sizeof(atio->sense_data)));
 577                                 atio->sense_len = sizeof(no_lun_sense_data);
 578                                 descr->data_resid = 0;
 579                                 descr->data_increment = 0;
 580                                 descr->status = SCSI_STATUS_CHECK_COND;
 581                                 break;
 582                         }
 583                         /*
 584                          * Direction is always relative
 585                          * to the initator.
 586                          */
 587                         atio->ccb_h.flags &= ~CAM_DIR_MASK;
 588                         atio->ccb_h.flags |= CAM_DIR_IN;
 589                         descr->data = &no_lun_inq_data;
 590                         descr->data_resid = MIN(sizeof(no_lun_inq_data),
 591                                                 scsi_2btoul(inq->length));
 592                         descr->data_increment = descr->data_resid;
 593                         descr->timeout = 5 * 1000;
 594                         descr->status = SCSI_STATUS_OK;
 595                         break;
 596                 }
 597                 case REQUEST_SENSE:
 598                 {
 599                         struct scsi_request_sense *rsense;
 600
 601                         rsense = (struct scsi_request_sense *)cdb;
 602                         /* Refer to static sense data */
 603                         atio->ccb_h.flags &= ~CAM_DIR_MASK;
 604                         atio->ccb_h.flags |= CAM_DIR_IN;
 605                         descr->data = &no_lun_sense_data;
 606                         descr->data_resid = request_sense_size;
 607                         descr->data_resid = MIN(descr->data_resid,
 608                                                 SCSI_CDB6_LEN(rsense->length));
 609                         descr->data_increment = descr->data_resid;
 610                         descr->timeout = 5 * 1000;
 611                         descr->status = SCSI_STATUS_OK;
 612                         break;
 613                 }
 614                 default:
 615                         /* Constant CA, tell initiator */
 616                         /* Direction is always relative to the initator */
 617                         atio->ccb_h.flags &= ~CAM_DIR_MASK;
 618                         atio->ccb_h.flags |= CAM_DIR_NONE;
 619                         bcopy(&no_lun_sense_data, &atio->sense_data,
 620                               min(sizeof(no_lun_sense_data),
 621                                   sizeof(atio->sense_data)));
 622                         atio->sense_len = sizeof (no_lun_sense_data);
 623                         descr->data_resid = 0;
 624                         descr->data_increment = 0;
 625                         descr->timeout = 5 * 1000;
 626                         descr->status = SCSI_STATUS_CHECK_COND;
 627                         break;
 628                 }
 629
 630                 /* Queue us up to receive a Continue Target I/O ccb. */
 631                 if ((atio->ccb_h.flags & CAM_DIS_DISCONNECT) != 0) {
 632                         TAILQ_INSERT_HEAD(&softc->work_queue, &atio->ccb_h,
 633                                           periph_links.tqe);
 634                         priority = 0;
 635                 } else {
 636                         TAILQ_INSERT_TAIL(&softc->work_queue, &atio->ccb_h,
 637                                           periph_links.tqe);
 638                         priority = CAM_PRIORITY_NORMAL;
 639                 }
 640                 xpt_schedule(periph, priority);
 641                 break;
 642         }
 643         case XPT_CONT_TARGET_IO:
 644         {
 645                 struct ccb_accept_tio *atio;
 646                 struct targbh_cmd_desc *desc;
 647
 648                 CAM_DEBUG(periph->path, CAM_DEBUG_SUBTRACE,
 649                           ("Received completed CTIO\n"));
 650                 atio = (struct ccb_accept_tio*)done_ccb->ccb_h.ccb_atio;
 651                 desc = (struct targbh_cmd_desc *)atio->ccb_h.ccb_descr;
 652
 653                 TAILQ_REMOVE(&softc->pending_queue, &atio->ccb_h,
 654                              periph_links.tqe);
 655
 656                 /*
 657                  * We could check for CAM_SENT_SENSE bein set here,
 658                  * but since we're not maintaining any CA/UA state,
 659                  * there's no point.
 660                  */
 661                 atio->sense_len = 0;
 662                 done_ccb->ccb_h.flags &= ~CAM_SEND_SENSE;
 663                 done_ccb->ccb_h.status &= ~CAM_SENT_SENSE;
 664
 665                 /*
 666                  * Any errors will not change the data we return,
 667                  * so make sure the queue is not left frozen.
 668                  * XXX - At some point there may be errors that
 669                  *       leave us in a connected state with the
 670                  *       initiator...
 671                  */
 672                 if ((done_ccb->ccb_h.status & CAM_DEV_QFRZN) != 0) {
 673                         printf("Releasing Queue\n");
 674                         cam_release_devq(done_ccb->ccb_h.path,
 675                                          /*relsim_flags*/0,
 676                                          /*reduction*/0,
 677                                          /*timeout*/0,
 678                                          /*getcount_only*/0);
 679                         done_ccb->ccb_h.status &= ~CAM_DEV_QFRZN;
 680                 }
 681                 desc->data_resid -= desc->data_increment;
 682                 xpt_release_ccb(done_ccb);
 683                 if (softc->state != TARGBH_STATE_TEARDOWN) {
 684
 685                         /*
 686                          * Send the original accept TIO back to the
 687                          * controller to handle more work.
 688                          */
 689                         CAM_DEBUG(periph->path, CAM_DEBUG_SUBTRACE,
 690                                   ("Returning ATIO to target\n"));
 691                         /* Restore wildcards */
 692                         atio->ccb_h.target_id = CAM_TARGET_WILDCARD;
 693                         atio->ccb_h.target_lun = CAM_LUN_WILDCARD;
 694                         xpt_action((union ccb *)atio);
 695                         break;
 696                 } else {
 697                         targbhfreedescr(desc);
 698                         free(atio, M_SCSIBH);
 699                 }
 700                 break;
 701         }
 702         case XPT_IMMEDIATE_NOTIFY:
 703         {
 704                 int frozen;
 705
 706                 frozen = (done_ccb->ccb_h.status & CAM_DEV_QFRZN) != 0;
 707                 if (softc->state == TARGBH_STATE_TEARDOWN
 708                  || done_ccb->ccb_h.status == CAM_REQ_ABORTED) {
 709                         printf("Freed an immediate notify\n");
 710                         xpt_free_ccb(done_ccb);
 711                 } else {
 712                         /* Requeue for another immediate event */
 713                         xpt_action(done_ccb);
 714                 }
 715                 if (frozen != 0)
 716                         cam_release_devq(periph->path,
 717                                          /*relsim_flags*/0,
 718                                          /*opening reduction*/0,
 719                                          /*timeout*/0,
 720                                          /*getcount_only*/0);
 721                 break;
 722         }
 723         default:
 724                 panic("targbhdone: Unexpected ccb opcode");
 725                 break;
 726         }
 727 }
 728
 729 #ifdef NOTYET
 730 static int
 731 targbherror(union ccb *ccb, u_int32_t cam_flags, u_int32_t sense_flags)
 732 {
 733         return 0;
 734 }
 735 #endif
 736
 737 static struct targbh_cmd_desc*
 738 targbhallocdescr()
 739 {
 740         struct targbh_cmd_desc* descr;
 741
 742         /* Allocate the targbh_descr structure */
 743         descr = (struct targbh_cmd_desc *)malloc(sizeof(*descr),
 744                                                M_SCSIBH, M_NOWAIT);
 745         if (descr == NULL)
 746                 return (NULL);
 747
 748         bzero(descr, sizeof(*descr));
 749
 750         /* Allocate buffer backing store */
 751         descr->backing_store = malloc(MAX_BUF_SIZE, M_SCSIBH, M_NOWAIT);
 752         if (descr->backing_store == NULL) {
 753                 free(descr, M_SCSIBH);
 754                 return (NULL);
 755         }
 756         descr->max_size = MAX_BUF_SIZE;
 757         return (descr);
 758 }
 759
 760 static void
 761 targbhfreedescr(struct targbh_cmd_desc *descr)
 762 {
 763         free(descr->backing_store, M_SCSIBH);
 764         free(descr, M_SCSIBH);
 765 }