sys/bus/cam/scsi/scsi_target.c

   1 /*
   2  * Generic SCSI Target Kernel Mode Driver
   3  *
   4  * Copyright (c) 2002 Nate Lawson.
   5  * Copyright (c) 1998, 1999, 2001, 2002 Justin T. Gibbs.
   6  * All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions, and the following disclaimer,
  13  *    without modification, immediately at the beginning of the file.
  14  * 2. The name of the author may not be used to endorse or promote products
  15  *    derived from this software without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
  21  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  * $FreeBSD: src/sys/cam/scsi/scsi_target.c,v 1.22.2.7 2003/02/18 22:07:10 njl Exp $
  30  */
  31
  32 #include <sys/param.h>
  33 #include <sys/systm.h>
  34 #include <sys/kernel.h>
  35 #include <sys/conf.h>
  36 #include <sys/device.h>
  37 #include <sys/malloc.h>
  38 #include <sys/vnode.h>
  39 #include <sys/devicestat.h>
  40 #include <sys/thread2.h>
  41 #include <sys/devfs.h>
  42
  43 #include "../cam.h"
  44 #include "../cam_ccb.h"
  45 #include "../cam_periph.h"
  46 #include "../cam_xpt_periph.h"
  47 #include "../cam_sim.h"
  48 #include "scsi_targetio.h"
  49
  50 /* Transaction information attached to each CCB sent by the user */
  51 struct targ_cmd_descr {
  52         struct cam_periph_map_info  mapinfo;
  53         TAILQ_ENTRY(targ_cmd_descr) tqe;
  54         union ccb *user_ccb;
  55         int        priority;
  56         int        func_code;
  57 };
  58
  59 /* Offset into the private CCB area for storing our descriptor */
  60 #define targ_descr      periph_priv.entries[1].ptr
  61
  62 TAILQ_HEAD(descr_queue, targ_cmd_descr);
  63
  64 typedef enum {
  65         TARG_STATE_RESV         = 0x00, /* Invalid state */
  66         TARG_STATE_OPENED       = 0x01, /* Device opened, softc initialized */
  67         TARG_STATE_LUN_ENABLED  = 0x02  /* Device enabled for a path */
  68 } targ_state;
  69
  70 /* Per-instance device software context */
  71 struct targ_softc {
  72         /* CCBs (CTIOs, ATIOs, INOTs) pending on the controller */
  73         struct ccb_queue         pending_ccb_queue;
  74
  75         /* Command descriptors awaiting CTIO resources from the XPT */
  76         struct descr_queue       work_queue;
  77
  78         /* Command descriptors that have been aborted back to the user. */
  79         struct descr_queue       abort_queue;
  80
  81         /*
  82          * Queue of CCBs that have been copied out to userland, but our
  83          * userland daemon has not yet seen.
  84          */
  85         struct ccb_queue         user_ccb_queue;
  86
  87         struct cam_periph       *periph;
  88         struct cam_path         *path;
  89         targ_state               state;
  90         struct kqinfo            read_kq;
  91         struct devstat           device_stats;
  92 };
  93
  94 static d_open_t         targopen;
  95 static d_close_t        targclose;
  96 static d_read_t         targread;
  97 static d_write_t        targwrite;
  98 static d_ioctl_t        targioctl;
  99 static d_kqfilter_t     targkqfilter;
 100 static d_clone_t        targclone;
 101 DEVFS_DECLARE_CLONE_BITMAP(targ);
 102
 103 static void             targfiltdetach(struct knote *kn);
 104 static int              targreadfilt(struct knote *kn, long hint);
 105 static int              targwritefilt(struct knote *kn, long hint);
 106 static struct filterops targread_filtops =
 107         { FILTEROP_ISFD, NULL, targfiltdetach, targreadfilt };
 108 static struct filterops targwrite_filtops =
 109         { FILTEROP_ISFD, NULL, targfiltdetach, targwritefilt };
 110
 111 static struct dev_ops targ_ops = {
 112         { "targ", 0, 0 },
 113         .d_open = targopen,
 114         .d_close = targclose,
 115         .d_read = targread,
 116         .d_write = targwrite,
 117         .d_ioctl = targioctl,
 118         .d_kqfilter = targkqfilter
 119 };
 120
 121 static cam_status       targendislun(struct cam_path *path, int enable,
 122                                      int grp6_len, int grp7_len);
 123 static cam_status       targenable(struct targ_softc *softc,
 124                                    struct cam_path *path,
 125                                    int grp6_len, int grp7_len);
 126 static cam_status       targdisable(struct targ_softc *softc);
 127 static periph_ctor_t    targctor;
 128 static periph_dtor_t    targdtor;
 129 static periph_start_t   targstart;
 130 static int              targusermerge(struct targ_softc *softc,
 131                                       struct targ_cmd_descr *descr,
 132                                       union ccb *ccb);
 133 static int              targsendccb(struct targ_softc *softc, union ccb *ccb,
 134                                     struct targ_cmd_descr *descr);
 135 static void             targdone(struct cam_periph *periph,
 136                                  union  ccb *done_ccb);
 137 static int              targreturnccb(struct targ_softc *softc,
 138                                       union  ccb *ccb);
 139 static union ccb *      targgetccb(struct targ_softc *softc, xpt_opcode type,
 140                                    int priority);
 141 static void             targfreeccb(struct targ_softc *softc, union ccb *ccb);
 142 static struct targ_cmd_descr *
 143                         targgetdescr(struct targ_softc *softc);
 144 static periph_init_t    targinit;
 145 static void             targasync(void *callback_arg, u_int32_t code,
 146                                   struct cam_path *path, void *arg);
 147 static void             abort_all_pending(struct targ_softc *softc);
 148 static void             notify_user(struct targ_softc *softc);
 149 static int              targcamstatus(cam_status status);
 150 static size_t           targccblen(xpt_opcode func_code);
 151
 152 static struct periph_driver targdriver =
 153 {
 154         targinit, "targ",
 155         TAILQ_HEAD_INITIALIZER(targdriver.units), /* generation */ 0
 156 };
 157 PERIPHDRIVER_DECLARE(targ, targdriver);
 158
 159 static MALLOC_DEFINE(M_TARG, "TARG", "TARG data");
 160
 161 /*
 162  * Create softc and initialize it. Only one proc can open each targ device.
 163  * There is no locking here because a periph doesn't get created until an
 164  * ioctl is issued to do so, and that can't happen until this method returns.
 165  */
 166 static int
 167 targopen(struct dev_open_args *ap)
 168 {
 169         cdev_t dev = ap->a_head.a_dev;
 170         struct targ_softc *softc;
 171
 172         if (dev->si_drv1 != 0) {
 173                 return (EBUSY);
 174         }
 175
 176         /* Mark device busy before any potentially blocking operations */
 177         dev->si_drv1 = (void *)~0;
 178         reference_dev(dev);             /* save ref for later destroy_dev() */
 179
 180         /* Create the targ device, allocate its softc, initialize it */
 181 #if 0
 182         make_dev(&targ_ops, minor(dev), UID_ROOT, GID_WHEEL, 0600,
 183                          "targ%d", lminor(dev));
 184 #endif
 185         softc = kmalloc(sizeof(*softc), M_TARG, M_INTWAIT | M_ZERO);
 186         dev->si_drv1 = softc;
 187         softc->state = TARG_STATE_OPENED;
 188         softc->periph = NULL;
 189         softc->path = NULL;
 190
 191         TAILQ_INIT(&softc->pending_ccb_queue);
 192         TAILQ_INIT(&softc->work_queue);
 193         TAILQ_INIT(&softc->abort_queue);
 194         TAILQ_INIT(&softc->user_ccb_queue);
 195
 196         return (0);
 197 }
 198
 199 /* Disable LUN if enabled and teardown softc */
 200 static int
 201 targclose(struct dev_close_args *ap)
 202 {
 203         cdev_t dev = ap->a_head.a_dev;
 204         struct targ_softc     *softc;
 205         struct cam_periph     *periph;
 206         int    error;
 207
 208         softc = (struct targ_softc *)dev->si_drv1;
 209         if ((softc->periph == NULL) ||
 210             (softc->state & TARG_STATE_LUN_ENABLED) == 0) {
 211                 devfs_clone_bitmap_put(&DEVFS_CLONE_BITMAP(targ), dev->si_uminor);
 212                 destroy_dev(dev);
 213                 kfree(softc, M_TARG);
 214                 return (0);
 215         }
 216
 217         /*
 218          * Acquire a hold on the periph so that it doesn't go away before
 219          * we are ready at the end of the function.
 220          */
 221         periph = softc->periph;
 222         cam_periph_acquire(periph);
 223         cam_periph_lock(periph);
 224         error = targdisable(softc);
 225         if (error == CAM_REQ_CMP) {
 226                 dev->si_drv1 = 0;
 227                 if (softc->periph != NULL) {
 228                         cam_periph_invalidate(softc->periph);
 229                         softc->periph = NULL;
 230                 }
 231                 destroy_dev(dev);       /* eats the open ref */
 232                 devfs_clone_bitmap_put(&DEVFS_CLONE_BITMAP(targ), dev->si_uminor);
 233                 kfree(softc, M_TARG);
 234         } else {
 235                 release_dev(dev);
 236         }
 237         cam_periph_unlock(periph);
 238         cam_periph_release(periph);
 239
 240         return (error);
 241 }
 242
 243 /* Enable/disable LUNs, set debugging level */
 244 static int
 245 targioctl(struct dev_ioctl_args *ap)
 246 {
 247         struct targ_softc *softc;
 248         cam_status         status;
 249
 250         softc = (struct targ_softc *)ap->a_head.a_dev->si_drv1;
 251
 252         switch (ap->a_cmd) {
 253         case TARGIOCENABLE:
 254         {
 255                 struct ioc_enable_lun   *new_lun;
 256                 struct cam_path         *path;
 257                 struct cam_sim          *sim;
 258
 259                 new_lun = (struct ioc_enable_lun *)ap->a_data;
 260                 status = xpt_create_path_unlocked(&path, /*periph*/NULL,
 261                                                   new_lun->path_id,
 262                                                   new_lun->target_id,
 263                                                   new_lun->lun_id);
 264                 if (status != CAM_REQ_CMP) {
 265                         kprintf("Couldn't create path, status %#x\n", status);
 266                         break;
 267                 }
 268                 sim = xpt_path_sim(path);
 269                 CAM_SIM_LOCK(sim);
 270                 status = targenable(softc, path, new_lun->grp6_len,
 271                                     new_lun->grp7_len);
 272                 xpt_free_path(path);
 273                 CAM_SIM_UNLOCK(sim);
 274                 break;
 275         }
 276         case TARGIOCDISABLE:
 277                 if (softc->periph == NULL) {
 278                         status = CAM_DEV_NOT_THERE;
 279                         break;
 280                 }
 281                 cam_periph_lock(softc->periph);
 282                 status = targdisable(softc);
 283                 cam_periph_unlock(softc->periph);
 284                 break;
 285         case TARGIOCDEBUG:
 286         {
 287 #ifdef  CAMDEBUG
 288                 struct ccb_debug cdbg;
 289
 290                 /* If no periph available, disallow debugging changes */
 291                 if ((softc->state & TARG_STATE_LUN_ENABLED) == 0) {
 292                         status = CAM_DEV_NOT_THERE;
 293                         break;
 294                 }
 295                 bzero(&cdbg, sizeof cdbg);
 296                 if (*((int *)ap->a_data) != 0)
 297                         cdbg.flags = CAM_DEBUG_PERIPH;
 298                 else
 299                         cdbg.flags = CAM_DEBUG_NONE;
 300                 cam_periph_lock(softc->periph);
 301                 xpt_setup_ccb(&cdbg.ccb_h, softc->path, /*priority*/0);
 302                 cdbg.ccb_h.func_code = XPT_DEBUG;
 303                 cdbg.ccb_h.cbfcnp = targdone;
 304
 305                 xpt_action((union ccb *)&cdbg);
 306                 cam_periph_unlock(softc->periph);
 307                 status = cdbg.ccb_h.status & CAM_STATUS_MASK;
 308 #else
 309                 status = CAM_FUNC_NOTAVAIL;
 310 #endif
 311                 break;
 312         }
 313         default:
 314                 status = CAM_PROVIDE_FAIL;
 315                 break;
 316         }
 317
 318         return (targcamstatus(status));
 319 }
 320
 321 static int
 322 targkqfilter(struct dev_kqfilter_args *ap)
 323 {
 324         struct  knote *kn = ap->a_kn;
 325         struct  targ_softc *softc;
 326
 327         softc = (struct targ_softc *)ap->a_head.a_dev->si_drv1;
 328
 329         ap->a_result = 0;
 330
 331         switch (kn->kn_filter) {
 332         case EVFILT_READ:
 333                 kn->kn_hook = (caddr_t)softc;
 334                 kn->kn_fop = &targread_filtops;
 335                 break;
 336         case EVFILT_WRITE:
 337                 kn->kn_hook = (caddr_t)softc;
 338                 kn->kn_fop = &targwrite_filtops;
 339         default:
 340                 ap->a_result = EOPNOTSUPP;
 341                 return (0);
 342         }
 343
 344         knote_insert(&softc->read_kq.ki_note, kn);
 345         return (0);
 346 }
 347
 348 static void
 349 targfiltdetach(struct knote *kn)
 350 {
 351         struct  targ_softc *softc;
 352
 353         softc = (struct targ_softc *)kn->kn_hook;
 354         knote_remove(&softc->read_kq.ki_note, kn);
 355 }
 356
 357 /* Notify the user's kqueue when the user queue or abort queue gets a CCB */
 358 static int
 359 targreadfilt(struct knote *kn, long hint)
 360 {
 361         struct targ_softc *softc;
 362         int     retval;
 363
 364         softc = (struct targ_softc *)kn->kn_hook;
 365         cam_periph_lock(softc->periph);
 366         retval = !TAILQ_EMPTY(&softc->user_ccb_queue) ||
 367                  !TAILQ_EMPTY(&softc->abort_queue);
 368         cam_periph_unlock(softc->periph);
 369         return (retval);
 370 }
 371
 372 /* write() is always ok */
 373 static int
 374 targwritefilt(struct knote *kn, long hint)
 375 {
 376         return (1);
 377 }
 378
 379 /* Send the HBA the enable/disable message */
 380 static cam_status
 381 targendislun(struct cam_path *path, int enable, int grp6_len, int grp7_len)
 382 {
 383         struct ccb_en_lun en_ccb;
 384         cam_status        status;
 385
 386         /* Tell the lun to begin answering selects */
 387         xpt_setup_ccb(&en_ccb.ccb_h, path, /*priority*/1);
 388         en_ccb.ccb_h.func_code = XPT_EN_LUN;
 389         /* Don't need support for any vendor specific commands */
 390         en_ccb.grp6_len = grp6_len;
 391         en_ccb.grp7_len = grp7_len;
 392         en_ccb.enable = enable ? 1 : 0;
 393         xpt_action((union ccb *)&en_ccb);
 394         status = en_ccb.ccb_h.status & CAM_STATUS_MASK;
 395         if (status != CAM_REQ_CMP) {
 396                 xpt_print(path, "%sable lun CCB rejected, status %#x\n",
 397                     enable ? "en" : "dis", status);
 398         }
 399         return (status);
 400 }
 401
 402 /* Enable target mode on a LUN, given its path */
 403 static cam_status
 404 targenable(struct targ_softc *softc, struct cam_path *path, int grp6_len,
 405            int grp7_len)
 406 {
 407         struct cam_periph *periph;
 408         struct ccb_pathinq cpi;
 409         cam_status         status;
 410
 411         if ((softc->state & TARG_STATE_LUN_ENABLED) != 0)
 412                 return (CAM_LUN_ALRDY_ENA);
 413
 414         /* Make sure SIM supports target mode */
 415         xpt_setup_ccb(&cpi.ccb_h, path, /*priority*/1);
 416         cpi.ccb_h.func_code = XPT_PATH_INQ;
 417         xpt_action((union ccb *)&cpi);
 418         status = cpi.ccb_h.status & CAM_STATUS_MASK;
 419         if (status != CAM_REQ_CMP) {
 420                 kprintf("pathinq failed, status %#x\n", status);
 421                 goto enable_fail;
 422         }
 423         if ((cpi.target_sprt & PIT_PROCESSOR) == 0) {
 424                 kprintf("controller does not support target mode\n");
 425                 status = CAM_FUNC_NOTAVAIL;
 426                 goto enable_fail;
 427         }
 428
 429         /* Destroy any periph on our path if it is disabled */
 430         periph = cam_periph_find(path, "targ");
 431         if (periph != NULL) {
 432                 struct targ_softc *del_softc;
 433
 434                 del_softc = (struct targ_softc *)periph->softc;
 435                 if ((del_softc->state & TARG_STATE_LUN_ENABLED) == 0) {
 436                         cam_periph_invalidate(del_softc->periph);
 437                         del_softc->periph = NULL;
 438                 } else {
 439                         kprintf("Requested path still in use by targ%d\n",
 440                                periph->unit_number);
 441                         status = CAM_LUN_ALRDY_ENA;
 442                         goto enable_fail;
 443                 }
 444         }
 445
 446         /* Create a periph instance attached to this path */
 447         status = cam_periph_alloc(targctor, NULL, targdtor, targstart,
 448                         "targ", CAM_PERIPH_BIO, path, targasync, 0, softc);
 449         if (status != CAM_REQ_CMP) {
 450                 kprintf("cam_periph_alloc failed, status %#x\n", status);
 451                 goto enable_fail;
 452         }
 453
 454         /* Ensure that the periph now exists. */
 455         if (cam_periph_find(path, "targ") == NULL) {
 456                 panic("targenable: succeeded but no periph?");
 457                 /* NOTREACHED */
 458         }
 459
 460         /* Send the enable lun message */
 461         status = targendislun(path, /*enable*/1, grp6_len, grp7_len);
 462         if (status != CAM_REQ_CMP) {
 463                 kprintf("enable lun failed, status %#x\n", status);
 464                 goto enable_fail;
 465         }
 466         softc->state |= TARG_STATE_LUN_ENABLED;
 467
 468 enable_fail:
 469         return (status);
 470 }
 471
 472 /* Disable this softc's target instance if enabled */
 473 static cam_status
 474 targdisable(struct targ_softc *softc)
 475 {
 476         cam_status status;
 477
 478         if ((softc->state & TARG_STATE_LUN_ENABLED) == 0)
 479                 return (CAM_REQ_CMP);
 480
 481         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targdisable\n"));
 482
 483         /* Abort any ccbs pending on the controller */
 484         crit_enter();
 485         abort_all_pending(softc);
 486         crit_exit();
 487
 488         /* Disable this lun */
 489         status = targendislun(softc->path, /*enable*/0,
 490                               /*grp6_len*/0, /*grp7_len*/0);
 491         if (status == CAM_REQ_CMP)
 492                 softc->state &= ~TARG_STATE_LUN_ENABLED;
 493         else
 494                 kprintf("Disable lun failed, status %#x\n", status);
 495
 496         return (status);
 497 }
 498
 499 /* Initialize a periph (called from cam_periph_alloc) */
 500 static cam_status
 501 targctor(struct cam_periph *periph, void *arg)
 502 {
 503         struct targ_softc *softc;
 504
 505         /* Store pointer to softc for periph-driven routines */
 506         softc = (struct targ_softc *)arg;
 507         periph->softc = softc;
 508         softc->periph = periph;
 509         softc->path = periph->path;
 510         return (CAM_REQ_CMP);
 511 }
 512
 513 static void
 514 targdtor(struct cam_periph *periph)
 515 {
 516         struct targ_softc     *softc;
 517         struct ccb_hdr        *ccb_h;
 518         struct targ_cmd_descr *descr;
 519
 520         softc = (struct targ_softc *)periph->softc;
 521
 522         /*
 523          * targdisable() aborts CCBs back to the user and leaves them
 524          * on user_ccb_queue and abort_queue in case the user is still
 525          * interested in them.  We free them now.
 526          */
 527         while ((ccb_h = TAILQ_FIRST(&softc->user_ccb_queue)) != NULL) {
 528                 TAILQ_REMOVE(&softc->user_ccb_queue, ccb_h, periph_links.tqe);
 529                 targfreeccb(softc, (union ccb *)ccb_h);
 530         }
 531         while ((descr = TAILQ_FIRST(&softc->abort_queue)) != NULL) {
 532                 TAILQ_REMOVE(&softc->abort_queue, descr, tqe);
 533                 kfree(descr, M_TARG);
 534         }
 535
 536         softc->periph = NULL;
 537         softc->path = NULL;
 538         periph->softc = NULL;
 539 }
 540
 541 /* Receive CCBs from user mode proc and send them to the HBA */
 542 static int
 543 targwrite(struct dev_write_args *ap)
 544 {
 545         struct uio *uio = ap->a_uio;
 546         union ccb *user_ccb;
 547         struct targ_softc *softc;
 548         struct targ_cmd_descr *descr;
 549         int write_len, error;
 550         int func_code, priority;
 551
 552         softc = (struct targ_softc *)ap->a_head.a_dev->si_drv1;
 553         write_len = error = 0;
 554         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 555                   ("write - uio_resid %zu\n", uio->uio_resid));
 556         while (uio->uio_resid >= sizeof(user_ccb) && error == 0) {
 557                 union ccb *ccb;
 558
 559                 error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
 560                 if (error != 0) {
 561                         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 562                                   ("write - uiomove failed (%d)\n", error));
 563                         break;
 564                 }
 565                 priority = fuword(&user_ccb->ccb_h.pinfo.priority);
 566                 if (priority == -1) {
 567                         error = EINVAL;
 568                         break;
 569                 }
 570                 func_code = fuword(&user_ccb->ccb_h.func_code);
 571                 switch (func_code) {
 572                 case XPT_ACCEPT_TARGET_IO:
 573                 case XPT_IMMED_NOTIFY:
 574                         cam_periph_lock(softc->periph);
 575                         ccb = targgetccb(softc, func_code, priority);
 576                         descr = (struct targ_cmd_descr *)ccb->ccb_h.targ_descr;
 577                         descr->user_ccb = user_ccb;
 578                         descr->func_code = func_code;
 579                         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 580                                   ("Sent ATIO/INOT (%p)\n", user_ccb));
 581                         xpt_action(ccb);
 582                         TAILQ_INSERT_TAIL(&softc->pending_ccb_queue,
 583                                           &ccb->ccb_h,
 584                                           periph_links.tqe);
 585                         cam_periph_unlock(softc->periph);
 586                         break;
 587                 default:
 588                         cam_periph_lock(softc->periph);
 589                         if ((func_code & XPT_FC_QUEUED) != 0) {
 590                                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 591                                           ("Sending queued ccb %#x (%p)\n",
 592                                           func_code, user_ccb));
 593                                 descr = targgetdescr(softc);
 594                                 descr->user_ccb = user_ccb;
 595                                 descr->priority = priority;
 596                                 descr->func_code = func_code;
 597                                 crit_enter();
 598                                 TAILQ_INSERT_TAIL(&softc->work_queue,
 599                                                   descr, tqe);
 600                                 crit_exit();
 601                                 xpt_schedule(softc->periph, priority);
 602                         } else {
 603                                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 604                                           ("Sending inline ccb %#x (%p)\n",
 605                                           func_code, user_ccb));
 606                                 ccb = targgetccb(softc, func_code, priority);
 607                                 descr = (struct targ_cmd_descr *)
 608                                          ccb->ccb_h.targ_descr;
 609                                 descr->user_ccb = user_ccb;
 610                                 descr->priority = priority;
 611                                 descr->func_code = func_code;
 612                                 if (targusermerge(softc, descr, ccb) != EFAULT)
 613                                         targsendccb(softc, ccb, descr);
 614                                 targreturnccb(softc, ccb);
 615                         }
 616                         cam_periph_unlock(softc->periph);
 617                         break;
 618                 }
 619                 write_len += sizeof(user_ccb);
 620         }
 621
 622         /*
 623          * If we've successfully taken in some amount of
 624          * data, return success for that data first.  If
 625          * an error is persistent, it will be reported
 626          * on the next write.
 627          */
 628         if (error != 0 && write_len == 0)
 629                 return (error);
 630         if (write_len == 0 && uio->uio_resid != 0)
 631                 return (ENOSPC);
 632         return (0);
 633 }
 634
 635 /* Process requests (descrs) via the periph-supplied CCBs */
 636 static void
 637 targstart(struct cam_periph *periph, union ccb *start_ccb)
 638 {
 639         struct targ_softc *softc;
 640         struct targ_cmd_descr *descr, *next_descr;
 641         int error;
 642
 643         softc = (struct targ_softc *)periph->softc;
 644         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targstart %p\n", start_ccb));
 645
 646         crit_enter();
 647         descr = TAILQ_FIRST(&softc->work_queue);
 648         if (descr == NULL) {
 649                 crit_exit();
 650                 xpt_release_ccb(start_ccb);
 651         } else {
 652                 TAILQ_REMOVE(&softc->work_queue, descr, tqe);
 653                 next_descr = TAILQ_FIRST(&softc->work_queue);
 654                 crit_exit();
 655
 656                 /* Initiate a transaction using the descr and supplied CCB */
 657                 error = targusermerge(softc, descr, start_ccb);
 658                 if (error == 0)
 659                         error = targsendccb(softc, start_ccb, descr);
 660                 if (error != 0) {
 661                         xpt_print(periph->path,
 662                             "targsendccb failed, err %d\n", error);
 663                         xpt_release_ccb(start_ccb);
 664                         suword(&descr->user_ccb->ccb_h.status,
 665                                CAM_REQ_CMP_ERR);
 666                         crit_enter();
 667                         TAILQ_INSERT_TAIL(&softc->abort_queue, descr, tqe);
 668                         crit_exit();
 669                         notify_user(softc);
 670                 }
 671
 672                 /* If we have more work to do, stay scheduled */
 673                 if (next_descr != NULL)
 674                         xpt_schedule(periph, next_descr->priority);
 675         }
 676 }
 677
 678 static int
 679 targusermerge(struct targ_softc *softc, struct targ_cmd_descr *descr,
 680               union ccb *ccb)
 681 {
 682         struct ccb_hdr *u_ccbh, *k_ccbh;
 683         size_t ccb_len;
 684         int error;
 685
 686         u_ccbh = &descr->user_ccb->ccb_h;
 687         k_ccbh = &ccb->ccb_h;
 688
 689         /*
 690          * There are some fields in the CCB header that need to be
 691          * preserved, the rest we get from the user ccb. (See xpt_merge_ccb)
 692          */
 693         xpt_setup_ccb(k_ccbh, softc->path, descr->priority);
 694         k_ccbh->retry_count = fuword(&u_ccbh->retry_count);
 695         k_ccbh->func_code = descr->func_code;
 696         k_ccbh->flags = fuword(&u_ccbh->flags);
 697         k_ccbh->timeout = fuword(&u_ccbh->timeout);
 698         ccb_len = targccblen(k_ccbh->func_code) - sizeof(struct ccb_hdr);
 699         error = copyin(u_ccbh + 1, k_ccbh + 1, ccb_len);
 700         if (error != 0) {
 701                 k_ccbh->status = CAM_REQ_CMP_ERR;
 702                 return (error);
 703         }
 704
 705         /* Translate usermode abort_ccb pointer to its kernel counterpart */
 706         if (k_ccbh->func_code == XPT_ABORT) {
 707                 struct ccb_abort *cab;
 708                 struct ccb_hdr *ccb_h;
 709
 710                 cab = (struct ccb_abort *)ccb;
 711                 crit_enter();
 712                 TAILQ_FOREACH(ccb_h, &softc->pending_ccb_queue,
 713                     periph_links.tqe) {
 714                         struct targ_cmd_descr *ab_descr;
 715
 716                         ab_descr = (struct targ_cmd_descr *)ccb_h->targ_descr;
 717                         if (ab_descr->user_ccb == cab->abort_ccb) {
 718                                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 719                                           ("Changing abort for %p to %p\n",
 720                                           cab->abort_ccb, ccb_h));
 721                                 cab->abort_ccb = (union ccb *)ccb_h;
 722                                 break;
 723                         }
 724                 }
 725                 crit_exit();
 726                 /* CCB not found, set appropriate status */
 727                 if (ccb_h == NULL) {
 728                         k_ccbh->status = CAM_PATH_INVALID;
 729                         error = ESRCH;
 730                 }
 731         }
 732
 733         return (error);
 734 }
 735
 736 /* Build and send a kernel CCB formed from descr->user_ccb */
 737 static int
 738 targsendccb(struct targ_softc *softc, union ccb *ccb,
 739             struct targ_cmd_descr *descr)
 740 {
 741         struct cam_periph_map_info *mapinfo;
 742         struct ccb_hdr *ccb_h;
 743         int error;
 744
 745         ccb_h = &ccb->ccb_h;
 746         mapinfo = &descr->mapinfo;
 747         mapinfo->num_bufs_used = 0;
 748
 749         /*
 750          * There's no way for the user to have a completion
 751          * function, so we put our own completion function in here.
 752          * We also stash in a reference to our descriptor so targreturnccb()
 753          * can find our mapping info.
 754          */
 755         ccb_h->cbfcnp = targdone;
 756         ccb_h->targ_descr = descr;
 757
 758         /*
 759          * We only attempt to map the user memory into kernel space
 760          * if they haven't passed in a physical memory pointer,
 761          * and if there is actually an I/O operation to perform.
 762          * Right now cam_periph_mapmem() only supports SCSI and device
 763          * match CCBs.  For the SCSI CCBs, we only pass the CCB in if
 764          * there's actually data to map.  cam_periph_mapmem() will do the
 765          * right thing, even if there isn't data to map, but since CCBs
 766          * without data are a reasonably common occurance (e.g. test unit
 767          * ready), it will save a few cycles if we check for it here.
 768          */
 769         if (((ccb_h->flags & CAM_DATA_PHYS) == 0)
 770          && (((ccb_h->func_code == XPT_CONT_TARGET_IO)
 771             && ((ccb_h->flags & CAM_DIR_MASK) != CAM_DIR_NONE))
 772           || (ccb_h->func_code == XPT_DEV_MATCH))) {
 773
 774                 error = cam_periph_mapmem(ccb, mapinfo);
 775
 776                 /*
 777                  * cam_periph_mapmem returned an error, we can't continue.
 778                  * Return the error to the user.
 779                  */
 780                 if (error) {
 781                         ccb_h->status = CAM_REQ_CMP_ERR;
 782                         mapinfo->num_bufs_used = 0;
 783                         return (error);
 784                 }
 785         }
 786
 787         /*
 788          * Once queued on the pending CCB list, this CCB will be protected
 789          * by our error recovery handler.
 790          */
 791         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("sendccb %p\n", ccb));
 792         if (XPT_FC_IS_QUEUED(ccb)) {
 793                 crit_enter();
 794                 TAILQ_INSERT_TAIL(&softc->pending_ccb_queue, ccb_h,
 795                                   periph_links.tqe);
 796                 crit_exit();
 797         }
 798         xpt_action(ccb);
 799
 800         return (0);
 801 }
 802
 803 /* Completion routine for CCBs (called in a critical section) */
 804 static void
 805 targdone(struct cam_periph *periph, union ccb *done_ccb)
 806 {
 807         struct targ_softc *softc;
 808
 809         CAM_DEBUG(periph->path, CAM_DEBUG_PERIPH, ("targdone %p\n", done_ccb));
 810         softc = (struct targ_softc *)periph->softc;
 811         TAILQ_REMOVE(&softc->pending_ccb_queue, &done_ccb->ccb_h,
 812                      periph_links.tqe);
 813
 814         /* If we're no longer enabled, throw away CCB */
 815         if ((softc->state & TARG_STATE_LUN_ENABLED) == 0) {
 816                 targfreeccb(softc, done_ccb);
 817                 return;
 818         }
 819         /* abort_all_pending() waits for pending queue to be empty */
 820         if (TAILQ_EMPTY(&softc->pending_ccb_queue))
 821                 wakeup(&softc->pending_ccb_queue);
 822
 823         switch (done_ccb->ccb_h.func_code) {
 824         /* All FC_*_QUEUED CCBs go back to userland */
 825         case XPT_IMMED_NOTIFY:
 826         case XPT_ACCEPT_TARGET_IO:
 827         case XPT_CONT_TARGET_IO:
 828                 TAILQ_INSERT_TAIL(&softc->user_ccb_queue, &done_ccb->ccb_h,
 829                                   periph_links.tqe);
 830                 notify_user(softc);
 831                 break;
 832         default:
 833                 panic("targdone: impossible xpt opcode %#x",
 834                       done_ccb->ccb_h.func_code);
 835                 /* NOTREACHED */
 836         }
 837 }
 838
 839 /* Return CCBs to the user from the user queue and abort queue */
 840 static int
 841 targread(struct dev_read_args *ap)
 842 {
 843         struct uio *uio = ap->a_uio;
 844         struct descr_queue      *abort_queue;
 845         struct targ_cmd_descr   *user_descr;
 846         struct targ_softc       *softc;
 847         struct ccb_queue  *user_queue;
 848         struct ccb_hdr    *ccb_h;
 849         union  ccb        *user_ccb;
 850         int                read_len, error;
 851
 852         error = 0;
 853         read_len = 0;
 854         softc = (struct targ_softc *)ap->a_head.a_dev->si_drv1;
 855         user_queue = &softc->user_ccb_queue;
 856         abort_queue = &softc->abort_queue;
 857         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targread\n"));
 858
 859         /* If no data is available, wait or return immediately */
 860         cam_periph_lock(softc->periph);
 861         ccb_h = TAILQ_FIRST(user_queue);
 862         user_descr = TAILQ_FIRST(abort_queue);
 863         while (ccb_h == NULL && user_descr == NULL) {
 864                 if ((ap->a_ioflag & IO_NDELAY) == 0) {
 865                         error = sim_lock_sleep(user_queue, PCATCH, "targrd", 0,
 866                                                softc->periph->sim->lock);
 867                         ccb_h = TAILQ_FIRST(user_queue);
 868                         user_descr = TAILQ_FIRST(abort_queue);
 869                         if (error != 0) {
 870                                 if (error == ERESTART) {
 871                                         continue;
 872                                 } else {
 873                                         goto read_fail;
 874                                 }
 875                         }
 876                 } else {
 877                         cam_periph_unlock(softc->periph);
 878                         return (EAGAIN);
 879                 }
 880         }
 881
 882         /* Data is available so fill the user's buffer */
 883         while (ccb_h != NULL) {
 884                 struct targ_cmd_descr *descr;
 885
 886                 if (uio->uio_resid < sizeof(user_ccb))
 887                         break;
 888                 TAILQ_REMOVE(user_queue, ccb_h, periph_links.tqe);
 889                 descr = (struct targ_cmd_descr *)ccb_h->targ_descr;
 890                 user_ccb = descr->user_ccb;
 891                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 892                           ("targread ccb %p (%p)\n", ccb_h, user_ccb));
 893                 error = targreturnccb(softc, (union ccb *)ccb_h);
 894                 if (error != 0)
 895                         goto read_fail;
 896                 cam_periph_unlock(softc->periph);
 897                 error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
 898                 cam_periph_lock(softc->periph);
 899                 if (error != 0)
 900                         goto read_fail;
 901                 read_len += sizeof(user_ccb);
 902
 903                 ccb_h = TAILQ_FIRST(user_queue);
 904         }
 905
 906         /* Flush out any aborted descriptors */
 907         while (user_descr != NULL) {
 908                 if (uio->uio_resid < sizeof(user_ccb))
 909                         break;
 910                 TAILQ_REMOVE(abort_queue, user_descr, tqe);
 911                 user_ccb = user_descr->user_ccb;
 912                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 913                           ("targread aborted descr %p (%p)\n",
 914                           user_descr, user_ccb));
 915                 suword(&user_ccb->ccb_h.status, CAM_REQ_ABORTED);
 916                 cam_periph_unlock(softc->periph);
 917                 error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
 918                 cam_periph_lock(softc->periph);
 919                 if (error != 0)
 920                         goto read_fail;
 921                 read_len += sizeof(user_ccb);
 922
 923                 user_descr = TAILQ_FIRST(abort_queue);
 924         }
 925
 926         /*
 927          * If we've successfully read some amount of data, don't report an
 928          * error.  If the error is persistent, it will be reported on the
 929          * next read().
 930          */
 931         if (read_len == 0 && uio->uio_resid != 0)
 932                 error = ENOSPC;
 933
 934 read_fail:
 935         cam_periph_unlock(softc->periph);
 936         return (error);
 937 }
 938
 939 /* Copy completed ccb back to the user */
 940 static int
 941 targreturnccb(struct targ_softc *softc, union ccb *ccb)
 942 {
 943         struct targ_cmd_descr *descr;
 944         struct ccb_hdr *u_ccbh;
 945         size_t ccb_len;
 946         int error;
 947
 948         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targreturnccb %p\n", ccb));
 949         descr = (struct targ_cmd_descr *)ccb->ccb_h.targ_descr;
 950         u_ccbh = &descr->user_ccb->ccb_h;
 951
 952         /* Copy out the central portion of the ccb_hdr */
 953         copyout(&ccb->ccb_h.retry_count, &u_ccbh->retry_count,
 954                 offsetof(struct ccb_hdr, periph_priv) -
 955                 offsetof(struct ccb_hdr, retry_count));
 956
 957         /* Copy out the rest of the ccb (after the ccb_hdr) */
 958         ccb_len = targccblen(ccb->ccb_h.func_code) - sizeof(struct ccb_hdr);
 959         if (descr->mapinfo.num_bufs_used != 0)
 960                 cam_periph_unmapmem(ccb, &descr->mapinfo);
 961         error = copyout(&ccb->ccb_h + 1, u_ccbh + 1, ccb_len);
 962         if (error != 0) {
 963                 xpt_print(softc->path,
 964                     "targreturnccb - CCB copyout failed (%d)\n", error);
 965         }
 966         /* Free CCB or send back to devq. */
 967         targfreeccb(softc, ccb);
 968
 969         return (error);
 970 }
 971
 972 static union ccb *
 973 targgetccb(struct targ_softc *softc, xpt_opcode type, int priority)
 974 {
 975         union ccb *ccb;
 976         int ccb_len;
 977
 978         ccb_len = targccblen(type);
 979         ccb = kmalloc(ccb_len, M_TARG, M_INTWAIT);
 980         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("getccb %p\n", ccb));
 981
 982         xpt_setup_ccb(&ccb->ccb_h, softc->path, priority);
 983         ccb->ccb_h.func_code = type;
 984         ccb->ccb_h.cbfcnp = targdone;
 985         ccb->ccb_h.targ_descr = targgetdescr(softc);
 986         return (ccb);
 987 }
 988
 989 static void
 990 targfreeccb(struct targ_softc *softc, union ccb *ccb)
 991 {
 992         CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH, ("targfreeccb descr %p and\n",
 993                         ccb->ccb_h.targ_descr));
 994         kfree(ccb->ccb_h.targ_descr, M_TARG);
 995
 996         switch (ccb->ccb_h.func_code) {
 997         case XPT_ACCEPT_TARGET_IO:
 998         case XPT_IMMED_NOTIFY:
 999                 CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH, ("freeing ccb %p\n", ccb));
1000                 kfree(ccb, M_TARG);
1001                 break;
1002         default:
1003                 /* Send back CCB if we got it from the periph */
1004                 if (XPT_FC_IS_QUEUED(ccb)) {
1005                         CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH,
1006                                         ("returning queued ccb %p\n", ccb));
1007                         xpt_release_ccb(ccb);
1008                 } else {
1009                         CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH,
1010                                         ("freeing ccb %p\n", ccb));
1011                         kfree(ccb, M_TARG);
1012                 }
1013                 break;
1014         }
1015 }
1016
1017 static struct targ_cmd_descr *
1018 targgetdescr(struct targ_softc *softc)
1019 {
1020         struct targ_cmd_descr *descr;
1021
1022         descr = kmalloc(sizeof(*descr), M_TARG, M_INTWAIT);
1023         descr->mapinfo.num_bufs_used = 0;
1024         return (descr);
1025 }
1026
1027 static int
1028 targclone(struct dev_clone_args *ap)
1029 {
1030         int unit;
1031
1032         unit = devfs_clone_bitmap_get(&DEVFS_CLONE_BITMAP(targ), 0);
1033         ap->a_dev = make_only_dev(&targ_ops, unit, UID_ROOT, GID_WHEEL,
1034                                   0600, "targ%d", unit);
1035         return 0;
1036 }
1037
1038 static void
1039 targinit(void)
1040 {
1041         make_autoclone_dev(&targ_ops, &DEVFS_CLONE_BITMAP(targ),
1042                 targclone, UID_ROOT, GID_WHEEL, 0600, "targ");
1043         /* XXX: need uninit or so? */
1044 }
1045
1046 static void
1047 targasync(void *callback_arg, u_int32_t code, struct cam_path *path, void *arg)
1048 {
1049         /* All events are handled in usermode by INOTs */
1050         panic("targasync() called, should be an INOT instead");
1051 }
1052
1053 /* Cancel all pending requests and CCBs awaiting work. */
1054 static void
1055 abort_all_pending(struct targ_softc *softc)
1056 {
1057         struct targ_cmd_descr   *descr;
1058         struct ccb_abort         cab;
1059         struct ccb_hdr          *ccb_h;
1060         struct cam_sim          *sim;
1061
1062         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("abort_all_pending\n"));
1063
1064         /* First abort the descriptors awaiting resources */
1065         while ((descr = TAILQ_FIRST(&softc->work_queue)) != NULL) {
1066                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
1067                           ("Aborting descr from workq %p\n", descr));
1068                 TAILQ_REMOVE(&softc->work_queue, descr, tqe);
1069                 TAILQ_INSERT_TAIL(&softc->abort_queue, descr, tqe);
1070         }
1071
1072         /*
1073          * Then abort all pending CCBs.
1074          * targdone() will return the aborted CCB via user_ccb_queue
1075          */
1076         xpt_setup_ccb(&cab.ccb_h, softc->path, /*priority*/0);
1077         cab.ccb_h.func_code = XPT_ABORT;
1078         cab.ccb_h.status = CAM_REQ_CMP_ERR;
1079         TAILQ_FOREACH(ccb_h, &softc->pending_ccb_queue, periph_links.tqe) {
1080                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
1081                           ("Aborting pending CCB %p\n", ccb_h));
1082                 cab.abort_ccb = (union ccb *)ccb_h;
1083                 xpt_action((union ccb *)&cab);
1084                 if (cab.ccb_h.status != CAM_REQ_CMP) {
1085                         xpt_print(cab.ccb_h.path,
1086                             "Unable to abort CCB, status %#x\n",
1087                             cab.ccb_h.status);
1088                 }
1089         }
1090
1091         /* If we aborted at least one pending CCB ok, wait for it. */
1092         if (cab.ccb_h.status == CAM_REQ_CMP) {
1093                 sim = xpt_path_sim(softc->path);
1094                 sim_lock_sleep(&softc->pending_ccb_queue, PCATCH, "tgabrt", 0,
1095                                sim->lock);
1096         }
1097
1098         /* If we aborted anything from the work queue, wakeup user. */
1099         if (!TAILQ_EMPTY(&softc->user_ccb_queue)
1100          || !TAILQ_EMPTY(&softc->abort_queue))
1101                 notify_user(softc);
1102 }
1103
1104 /* Notify the user that data is ready */
1105 static void
1106 notify_user(struct targ_softc *softc)
1107 {
1108         /*
1109          * Notify users sleeping via poll(), kqueue(), and
1110          * blocking read().
1111          */
1112         KNOTE(&softc->read_kq.ki_note, 0);
1113         wakeup(&softc->user_ccb_queue);
1114 }
1115
1116 /* Convert CAM status to errno values */
1117 static int
1118 targcamstatus(cam_status status)
1119 {
1120         switch (status & CAM_STATUS_MASK) {
1121         case CAM_REQ_CMP:       /* CCB request completed without error */
1122                 return (0);
1123         case CAM_REQ_INPROG:    /* CCB request is in progress */
1124                 return (EINPROGRESS);
1125         case CAM_REQ_CMP_ERR:   /* CCB request completed with an error */
1126                 return (EIO);
1127         case CAM_PROVIDE_FAIL:  /* Unable to provide requested capability */
1128                 return (ENOTTY);
1129         case CAM_FUNC_NOTAVAIL: /* The requested function is not available */
1130                 return (ENOTSUP);
1131         case CAM_LUN_ALRDY_ENA: /* LUN is already enabled for target mode */
1132                 return (EADDRINUSE);
1133         case CAM_PATH_INVALID:  /* Supplied Path ID is invalid */
1134         case CAM_DEV_NOT_THERE: /* SCSI Device Not Installed/there */
1135                 return (ENOENT);
1136         case CAM_REQ_ABORTED:   /* CCB request aborted by the host */
1137                 return (ECANCELED);
1138         case CAM_CMD_TIMEOUT:   /* Command timeout */
1139                 return (ETIMEDOUT);
1140         case CAM_REQUEUE_REQ:   /* Requeue to preserve transaction ordering */
1141                 return (EAGAIN);
1142         case CAM_REQ_INVALID:   /* CCB request was invalid */
1143                 return (EINVAL);
1144         case CAM_RESRC_UNAVAIL: /* Resource Unavailable */
1145                 return (ENOMEM);
1146         case CAM_BUSY:          /* CAM subsytem is busy */
1147         case CAM_UA_ABORT:      /* Unable to abort CCB request */
1148                 return (EBUSY);
1149         default:
1150                 return (ENXIO);
1151         }
1152 }
1153
1154 static size_t
1155 targccblen(xpt_opcode func_code)
1156 {
1157         int len;
1158
1159         /* Codes we expect to see as a target */
1160         switch (func_code) {
1161         case XPT_CONT_TARGET_IO:
1162         case XPT_SCSI_IO:
1163                 len = sizeof(struct ccb_scsiio);
1164                 break;
1165         case XPT_ACCEPT_TARGET_IO:
1166                 len = sizeof(struct ccb_accept_tio);
1167                 break;
1168         case XPT_IMMED_NOTIFY:
1169                 len = sizeof(struct ccb_immed_notify);
1170                 break;
1171         case XPT_REL_SIMQ:
1172                 len = sizeof(struct ccb_relsim);
1173                 break;
1174         case XPT_PATH_INQ:
1175                 len = sizeof(struct ccb_pathinq);
1176                 break;
1177         case XPT_DEBUG:
1178                 len = sizeof(struct ccb_debug);
1179                 break;
1180         case XPT_ABORT:
1181                 len = sizeof(struct ccb_abort);
1182                 break;
1183         case XPT_EN_LUN:
1184                 len = sizeof(struct ccb_en_lun);
1185                 break;
1186         default:
1187                 len = sizeof(union ccb);
1188                 break;
1189         }
1190
1191         return (len);
1192 }