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  * $DragonFly: src/sys/bus/cam/scsi/scsi_target.c,v 1.20 2008/07/18 00:07:23 dillon Exp $
  31  */
  32
  33 #include <sys/param.h>
  34 #include <sys/systm.h>
  35 #include <sys/kernel.h>
  36 #include <sys/conf.h>
  37 #include <sys/device.h>
  38 #include <sys/malloc.h>
  39 #include <sys/vnode.h>
  40 #include <sys/devicestat.h>
  41 #include <sys/thread2.h>
  42 #include <sys/devfs.h>
  43
  44 #include "../cam.h"
  45 #include "../cam_ccb.h"
  46 #include "../cam_periph.h"
  47 #include "../cam_xpt_periph.h"
  48 #include "../cam_sim.h"
  49 #include "scsi_targetio.h"
  50
  51 /* Transaction information attached to each CCB sent by the user */
  52 struct targ_cmd_descr {
  53         struct cam_periph_map_info  mapinfo;
  54         TAILQ_ENTRY(targ_cmd_descr) tqe;
  55         union ccb *user_ccb;
  56         int        priority;
  57         int        func_code;
  58 };
  59
  60 /* Offset into the private CCB area for storing our descriptor */
  61 #define targ_descr      periph_priv.entries[1].ptr
  62
  63 TAILQ_HEAD(descr_queue, targ_cmd_descr);
  64
  65 typedef enum {
  66         TARG_STATE_RESV         = 0x00, /* Invalid state */
  67         TARG_STATE_OPENED       = 0x01, /* Device opened, softc initialized */
  68         TARG_STATE_LUN_ENABLED  = 0x02  /* Device enabled for a path */
  69 } targ_state;
  70
  71 /* Per-instance device software context */
  72 struct targ_softc {
  73         /* CCBs (CTIOs, ATIOs, INOTs) pending on the controller */
  74         struct ccb_queue         pending_ccb_queue;
  75
  76         /* Command descriptors awaiting CTIO resources from the XPT */
  77         struct descr_queue       work_queue;
  78
  79         /* Command descriptors that have been aborted back to the user. */
  80         struct descr_queue       abort_queue;
  81
  82         /*
  83          * Queue of CCBs that have been copied out to userland, but our
  84          * userland daemon has not yet seen.
  85          */
  86         struct ccb_queue         user_ccb_queue;
  87
  88         struct cam_periph       *periph;
  89         struct cam_path         *path;
  90         targ_state               state;
  91         struct kqinfo            read_kq;
  92         struct devstat           device_stats;
  93 };
  94
  95 static d_open_t         targopen;
  96 static d_close_t        targclose;
  97 static d_read_t         targread;
  98 static d_write_t        targwrite;
  99 static d_ioctl_t        targioctl;
 100 static d_kqfilter_t     targkqfilter;
 101 static d_clone_t        targclone;
 102 DEVFS_DECLARE_CLONE_BITMAP(targ);
 103
 104 static void             targfiltdetach(struct knote *kn);
 105 static int              targreadfilt(struct knote *kn, long hint);
 106 static int              targwritefilt(struct knote *kn, long hint);
 107 static struct filterops targread_filtops =
 108         { 1, NULL, targfiltdetach, targreadfilt };
 109 static struct filterops targwrite_filtops =
 110         { 1, NULL, targfiltdetach, targwritefilt };
 111
 112 #define TARG_CDEV_MAJOR 65
 113 static struct dev_ops targ_ops = {
 114         { "targ", TARG_CDEV_MAJOR, D_KQFILTER },
 115         .d_open = targopen,
 116         .d_close = targclose,
 117         .d_read = targread,
 118         .d_write = targwrite,
 119         .d_ioctl = targioctl,
 120         .d_kqfilter = targkqfilter
 121 };
 122
 123 static cam_status       targendislun(struct cam_path *path, int enable,
 124                                      int grp6_len, int grp7_len);
 125 static cam_status       targenable(struct targ_softc *softc,
 126                                    struct cam_path *path,
 127                                    int grp6_len, int grp7_len);
 128 static cam_status       targdisable(struct targ_softc *softc);
 129 static periph_ctor_t    targctor;
 130 static periph_dtor_t    targdtor;
 131 static periph_start_t   targstart;
 132 static int              targusermerge(struct targ_softc *softc,
 133                                       struct targ_cmd_descr *descr,
 134                                       union ccb *ccb);
 135 static int              targsendccb(struct targ_softc *softc, union ccb *ccb,
 136                                     struct targ_cmd_descr *descr);
 137 static void             targdone(struct cam_periph *periph,
 138                                  union  ccb *done_ccb);
 139 static int              targreturnccb(struct targ_softc *softc,
 140                                       union  ccb *ccb);
 141 static union ccb *      targgetccb(struct targ_softc *softc, xpt_opcode type,
 142                                    int priority);
 143 static void             targfreeccb(struct targ_softc *softc, union ccb *ccb);
 144 static struct targ_cmd_descr *
 145                         targgetdescr(struct targ_softc *softc);
 146 static periph_init_t    targinit;
 147 static void             targasync(void *callback_arg, u_int32_t code,
 148                                   struct cam_path *path, void *arg);
 149 static void             abort_all_pending(struct targ_softc *softc);
 150 static void             notify_user(struct targ_softc *softc);
 151 static int              targcamstatus(cam_status status);
 152 static size_t           targccblen(xpt_opcode func_code);
 153
 154 static struct periph_driver targdriver =
 155 {
 156         targinit, "targ",
 157         TAILQ_HEAD_INITIALIZER(targdriver.units), /* generation */ 0
 158 };
 159 PERIPHDRIVER_DECLARE(targ, targdriver);
 160
 161 static MALLOC_DEFINE(M_TARG, "TARG", "TARG data");
 162
 163 /*
 164  * Create softc and initialize it. Only one proc can open each targ device.
 165  * There is no locking here because a periph doesn't get created until an
 166  * ioctl is issued to do so, and that can't happen until this method returns.
 167  */
 168 static int
 169 targopen(struct dev_open_args *ap)
 170 {
 171         cdev_t dev = ap->a_head.a_dev;
 172         struct targ_softc *softc;
 173
 174         if (dev->si_drv1 != 0) {
 175                 return (EBUSY);
 176         }
 177
 178         /* Mark device busy before any potentially blocking operations */
 179         dev->si_drv1 = (void *)~0;
 180         reference_dev(dev);             /* save ref for later destroy_dev() */
 181
 182         /* Create the targ device, allocate its softc, initialize it */
 183 #if 0
 184         make_dev(&targ_ops, minor(dev), UID_ROOT, GID_WHEEL, 0600,
 185                          "targ%d", lminor(dev));
 186 #endif
 187         MALLOC(softc, struct targ_softc *, sizeof(*softc), M_TARG,
 188                M_INTWAIT | M_ZERO);
 189         dev->si_drv1 = softc;
 190         softc->state = TARG_STATE_OPENED;
 191         softc->periph = NULL;
 192         softc->path = NULL;
 193
 194         TAILQ_INIT(&softc->pending_ccb_queue);
 195         TAILQ_INIT(&softc->work_queue);
 196         TAILQ_INIT(&softc->abort_queue);
 197         TAILQ_INIT(&softc->user_ccb_queue);
 198
 199         return (0);
 200 }
 201
 202 /* Disable LUN if enabled and teardown softc */
 203 static int
 204 targclose(struct dev_close_args *ap)
 205 {
 206         cdev_t dev = ap->a_head.a_dev;
 207         struct targ_softc     *softc;
 208         struct cam_periph     *periph;
 209         int    error;
 210
 211         softc = (struct targ_softc *)dev->si_drv1;
 212         if ((softc->periph == NULL) ||
 213             (softc->state & TARG_STATE_LUN_ENABLED) == 0) {
 214                 devfs_clone_bitmap_put(&DEVFS_CLONE_BITMAP(targ), dev->si_uminor);
 215                 destroy_dev(dev);
 216                 FREE(softc, M_TARG);
 217                 return (0);
 218         }
 219
 220         /*
 221          * Acquire a hold on the periph so that it doesn't go away before
 222          * we are ready at the end of the function.
 223          */
 224         periph = softc->periph;
 225         cam_periph_acquire(periph);
 226         cam_periph_lock(periph);
 227         error = targdisable(softc);
 228         if (error == CAM_REQ_CMP) {
 229                 dev->si_drv1 = 0;
 230                 if (softc->periph != NULL) {
 231                         cam_periph_invalidate(softc->periph);
 232                         softc->periph = NULL;
 233                 }
 234                 destroy_dev(dev);       /* eats the open ref */
 235                 devfs_clone_bitmap_put(&DEVFS_CLONE_BITMAP(targ), dev->si_uminor);
 236                 FREE(softc, M_TARG);
 237         } else {
 238                 release_dev(dev);
 239         }
 240         cam_periph_unlock(periph);
 241         cam_periph_release(periph);
 242
 243         return (error);
 244 }
 245
 246 /* Enable/disable LUNs, set debugging level */
 247 static int
 248 targioctl(struct dev_ioctl_args *ap)
 249 {
 250         struct targ_softc *softc;
 251         cam_status         status;
 252
 253         softc = (struct targ_softc *)ap->a_head.a_dev->si_drv1;
 254
 255         switch (ap->a_cmd) {
 256         case TARGIOCENABLE:
 257         {
 258                 struct ioc_enable_lun   *new_lun;
 259                 struct cam_path         *path;
 260                 struct cam_sim          *sim;
 261
 262                 new_lun = (struct ioc_enable_lun *)ap->a_data;
 263                 status = xpt_create_path_unlocked(&path, /*periph*/NULL,
 264                                                   new_lun->path_id,
 265                                                   new_lun->target_id,
 266                                                   new_lun->lun_id);
 267                 if (status != CAM_REQ_CMP) {
 268                         kprintf("Couldn't create path, status %#x\n", status);
 269                         break;
 270                 }
 271                 sim = xpt_path_sim(path);
 272                 CAM_SIM_LOCK(sim);
 273                 status = targenable(softc, path, new_lun->grp6_len,
 274                                     new_lun->grp7_len);
 275                 xpt_free_path(path);
 276                 CAM_SIM_UNLOCK(sim);
 277                 break;
 278         }
 279         case TARGIOCDISABLE:
 280                 if (softc->periph == NULL) {
 281                         status = CAM_DEV_NOT_THERE;
 282                         break;
 283                 }
 284                 cam_periph_lock(softc->periph);
 285                 status = targdisable(softc);
 286                 cam_periph_unlock(softc->periph);
 287                 break;
 288         case TARGIOCDEBUG:
 289         {
 290 #ifdef  CAMDEBUG
 291                 struct ccb_debug cdbg;
 292
 293                 /* If no periph available, disallow debugging changes */
 294                 if ((softc->state & TARG_STATE_LUN_ENABLED) == 0) {
 295                         status = CAM_DEV_NOT_THERE;
 296                         break;
 297                 }
 298                 bzero(&cdbg, sizeof cdbg);
 299                 if (*((int *)ap->a_data) != 0)
 300                         cdbg.flags = CAM_DEBUG_PERIPH;
 301                 else
 302                         cdbg.flags = CAM_DEBUG_NONE;
 303                 cam_periph_lock(softc->periph);
 304                 xpt_setup_ccb(&cdbg.ccb_h, softc->path, /*priority*/0);
 305                 cdbg.ccb_h.func_code = XPT_DEBUG;
 306                 cdbg.ccb_h.cbfcnp = targdone;
 307
 308                 xpt_action((union ccb *)&cdbg);
 309                 cam_periph_unlock(softc->periph);
 310                 status = cdbg.ccb_h.status & CAM_STATUS_MASK;
 311 #else
 312                 status = CAM_FUNC_NOTAVAIL;
 313 #endif
 314                 break;
 315         }
 316         default:
 317                 status = CAM_PROVIDE_FAIL;
 318                 break;
 319         }
 320
 321         return (targcamstatus(status));
 322 }
 323
 324 static int
 325 targkqfilter(struct dev_kqfilter_args *ap)
 326 {
 327         struct  knote *kn = ap->a_kn;
 328         struct  targ_softc *softc;
 329
 330         softc = (struct targ_softc *)ap->a_head.a_dev->si_drv1;
 331
 332         ap->a_result = 0;
 333
 334         switch (kn->kn_filter) {
 335         case EVFILT_READ:
 336                 kn->kn_hook = (caddr_t)softc;
 337                 kn->kn_fop = &targread_filtops;
 338                 break;
 339         case EVFILT_WRITE:
 340                 kn->kn_hook = (caddr_t)softc;
 341                 kn->kn_fop = &targwrite_filtops;
 342         default:
 343                 ap->a_result = EOPNOTSUPP;
 344                 return (0);
 345         }
 346
 347         knote_insert(&softc->read_kq.ki_note, kn);
 348         return (0);
 349 }
 350
 351 static void
 352 targfiltdetach(struct knote *kn)
 353 {
 354         struct  targ_softc *softc;
 355
 356         softc = (struct targ_softc *)kn->kn_hook;
 357         knote_remove(&softc->read_kq.ki_note, kn);
 358 }
 359
 360 /* Notify the user's kqueue when the user queue or abort queue gets a CCB */
 361 static int
 362 targreadfilt(struct knote *kn, long hint)
 363 {
 364         struct targ_softc *softc;
 365         int     retval;
 366
 367         softc = (struct targ_softc *)kn->kn_hook;
 368         cam_periph_lock(softc->periph);
 369         retval = !TAILQ_EMPTY(&softc->user_ccb_queue) ||
 370                  !TAILQ_EMPTY(&softc->abort_queue);
 371         cam_periph_unlock(softc->periph);
 372         return (retval);
 373 }
 374
 375 /* write() is always ok */
 376 static int
 377 targwritefilt(struct knote *kn, long hint)
 378 {
 379         return (1);
 380 }
 381
 382 /* Send the HBA the enable/disable message */
 383 static cam_status
 384 targendislun(struct cam_path *path, int enable, int grp6_len, int grp7_len)
 385 {
 386         struct ccb_en_lun en_ccb;
 387         cam_status        status;
 388
 389         /* Tell the lun to begin answering selects */
 390         xpt_setup_ccb(&en_ccb.ccb_h, path, /*priority*/1);
 391         en_ccb.ccb_h.func_code = XPT_EN_LUN;
 392         /* Don't need support for any vendor specific commands */
 393         en_ccb.grp6_len = grp6_len;
 394         en_ccb.grp7_len = grp7_len;
 395         en_ccb.enable = enable ? 1 : 0;
 396         xpt_action((union ccb *)&en_ccb);
 397         status = en_ccb.ccb_h.status & CAM_STATUS_MASK;
 398         if (status != CAM_REQ_CMP) {
 399                 xpt_print(path, "%sable lun CCB rejected, status %#x\n",
 400                     enable ? "en" : "dis", status);
 401         }
 402         return (status);
 403 }
 404
 405 /* Enable target mode on a LUN, given its path */
 406 static cam_status
 407 targenable(struct targ_softc *softc, struct cam_path *path, int grp6_len,
 408            int grp7_len)
 409 {
 410         struct cam_periph *periph;
 411         struct ccb_pathinq cpi;
 412         cam_status         status;
 413
 414         if ((softc->state & TARG_STATE_LUN_ENABLED) != 0)
 415                 return (CAM_LUN_ALRDY_ENA);
 416
 417         /* Make sure SIM supports target mode */
 418         xpt_setup_ccb(&cpi.ccb_h, path, /*priority*/1);
 419         cpi.ccb_h.func_code = XPT_PATH_INQ;
 420         xpt_action((union ccb *)&cpi);
 421         status = cpi.ccb_h.status & CAM_STATUS_MASK;
 422         if (status != CAM_REQ_CMP) {
 423                 kprintf("pathinq failed, status %#x\n", status);
 424                 goto enable_fail;
 425         }
 426         if ((cpi.target_sprt & PIT_PROCESSOR) == 0) {
 427                 kprintf("controller does not support target mode\n");
 428                 status = CAM_FUNC_NOTAVAIL;
 429                 goto enable_fail;
 430         }
 431
 432         /* Destroy any periph on our path if it is disabled */
 433         periph = cam_periph_find(path, "targ");
 434         if (periph != NULL) {
 435                 struct targ_softc *del_softc;
 436
 437                 del_softc = (struct targ_softc *)periph->softc;
 438                 if ((del_softc->state & TARG_STATE_LUN_ENABLED) == 0) {
 439                         cam_periph_invalidate(del_softc->periph);
 440                         del_softc->periph = NULL;
 441                 } else {
 442                         kprintf("Requested path still in use by targ%d\n",
 443                                periph->unit_number);
 444                         status = CAM_LUN_ALRDY_ENA;
 445                         goto enable_fail;
 446                 }
 447         }
 448
 449         /* Create a periph instance attached to this path */
 450         status = cam_periph_alloc(targctor, NULL, targdtor, targstart,
 451                         "targ", CAM_PERIPH_BIO, path, targasync, 0, softc);
 452         if (status != CAM_REQ_CMP) {
 453                 kprintf("cam_periph_alloc failed, status %#x\n", status);
 454                 goto enable_fail;
 455         }
 456
 457         /* Ensure that the periph now exists. */
 458         if (cam_periph_find(path, "targ") == NULL) {
 459                 panic("targenable: succeeded but no periph?");
 460                 /* NOTREACHED */
 461         }
 462
 463         /* Send the enable lun message */
 464         status = targendislun(path, /*enable*/1, grp6_len, grp7_len);
 465         if (status != CAM_REQ_CMP) {
 466                 kprintf("enable lun failed, status %#x\n", status);
 467                 goto enable_fail;
 468         }
 469         softc->state |= TARG_STATE_LUN_ENABLED;
 470
 471 enable_fail:
 472         return (status);
 473 }
 474
 475 /* Disable this softc's target instance if enabled */
 476 static cam_status
 477 targdisable(struct targ_softc *softc)
 478 {
 479         cam_status status;
 480
 481         if ((softc->state & TARG_STATE_LUN_ENABLED) == 0)
 482                 return (CAM_REQ_CMP);
 483
 484         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targdisable\n"));
 485
 486         /* Abort any ccbs pending on the controller */
 487         crit_enter();
 488         abort_all_pending(softc);
 489         crit_exit();
 490
 491         /* Disable this lun */
 492         status = targendislun(softc->path, /*enable*/0,
 493                               /*grp6_len*/0, /*grp7_len*/0);
 494         if (status == CAM_REQ_CMP)
 495                 softc->state &= ~TARG_STATE_LUN_ENABLED;
 496         else
 497                 kprintf("Disable lun failed, status %#x\n", status);
 498
 499         return (status);
 500 }
 501
 502 /* Initialize a periph (called from cam_periph_alloc) */
 503 static cam_status
 504 targctor(struct cam_periph *periph, void *arg)
 505 {
 506         struct targ_softc *softc;
 507
 508         /* Store pointer to softc for periph-driven routines */
 509         softc = (struct targ_softc *)arg;
 510         periph->softc = softc;
 511         softc->periph = periph;
 512         softc->path = periph->path;
 513         return (CAM_REQ_CMP);
 514 }
 515
 516 static void
 517 targdtor(struct cam_periph *periph)
 518 {
 519         struct targ_softc     *softc;
 520         struct ccb_hdr        *ccb_h;
 521         struct targ_cmd_descr *descr;
 522
 523         softc = (struct targ_softc *)periph->softc;
 524
 525         /*
 526          * targdisable() aborts CCBs back to the user and leaves them
 527          * on user_ccb_queue and abort_queue in case the user is still
 528          * interested in them.  We free them now.
 529          */
 530         while ((ccb_h = TAILQ_FIRST(&softc->user_ccb_queue)) != NULL) {
 531                 TAILQ_REMOVE(&softc->user_ccb_queue, ccb_h, periph_links.tqe);
 532                 targfreeccb(softc, (union ccb *)ccb_h);
 533         }
 534         while ((descr = TAILQ_FIRST(&softc->abort_queue)) != NULL) {
 535                 TAILQ_REMOVE(&softc->abort_queue, descr, tqe);
 536                 FREE(descr, M_TARG);
 537         }
 538
 539         softc->periph = NULL;
 540         softc->path = NULL;
 541         periph->softc = NULL;
 542 }
 543
 544 /* Receive CCBs from user mode proc and send them to the HBA */
 545 static int
 546 targwrite(struct dev_write_args *ap)
 547 {
 548         struct uio *uio = ap->a_uio;
 549         union ccb *user_ccb;
 550         struct targ_softc *softc;
 551         struct targ_cmd_descr *descr;
 552         int write_len, error;
 553         int func_code, priority;
 554
 555         softc = (struct targ_softc *)ap->a_head.a_dev->si_drv1;
 556         write_len = error = 0;
 557         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 558                   ("write - uio_resid %zu\n", uio->uio_resid));
 559         while (uio->uio_resid >= sizeof(user_ccb) && error == 0) {
 560                 union ccb *ccb;
 561
 562                 error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
 563                 if (error != 0) {
 564                         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 565                                   ("write - uiomove failed (%d)\n", error));
 566                         break;
 567                 }
 568                 priority = fuword(&user_ccb->ccb_h.pinfo.priority);
 569                 if (priority == -1) {
 570                         error = EINVAL;
 571                         break;
 572                 }
 573                 func_code = fuword(&user_ccb->ccb_h.func_code);
 574                 switch (func_code) {
 575                 case XPT_ACCEPT_TARGET_IO:
 576                 case XPT_IMMED_NOTIFY:
 577                         cam_periph_lock(softc->periph);
 578                         ccb = targgetccb(softc, func_code, priority);
 579                         descr = (struct targ_cmd_descr *)ccb->ccb_h.targ_descr;
 580                         descr->user_ccb = user_ccb;
 581                         descr->func_code = func_code;
 582                         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 583                                   ("Sent ATIO/INOT (%p)\n", user_ccb));
 584                         xpt_action(ccb);
 585                         TAILQ_INSERT_TAIL(&softc->pending_ccb_queue,
 586                                           &ccb->ccb_h,
 587                                           periph_links.tqe);
 588                         cam_periph_unlock(softc->periph);
 589                         break;
 590                 default:
 591                         cam_periph_lock(softc->periph);
 592                         if ((func_code & XPT_FC_QUEUED) != 0) {
 593                                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 594                                           ("Sending queued ccb %#x (%p)\n",
 595                                           func_code, user_ccb));
 596                                 descr = targgetdescr(softc);
 597                                 descr->user_ccb = user_ccb;
 598                                 descr->priority = priority;
 599                                 descr->func_code = func_code;
 600                                 crit_enter();
 601                                 TAILQ_INSERT_TAIL(&softc->work_queue,
 602                                                   descr, tqe);
 603                                 crit_exit();
 604                                 xpt_schedule(softc->periph, priority);
 605                         } else {
 606                                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 607                                           ("Sending inline ccb %#x (%p)\n",
 608                                           func_code, user_ccb));
 609                                 ccb = targgetccb(softc, func_code, priority);
 610                                 descr = (struct targ_cmd_descr *)
 611                                          ccb->ccb_h.targ_descr;
 612                                 descr->user_ccb = user_ccb;
 613                                 descr->priority = priority;
 614                                 descr->func_code = func_code;
 615                                 if (targusermerge(softc, descr, ccb) != EFAULT)
 616                                         targsendccb(softc, ccb, descr);
 617                                 targreturnccb(softc, ccb);
 618                         }
 619                         cam_periph_unlock(softc->periph);
 620                         break;
 621                 }
 622                 write_len += sizeof(user_ccb);
 623         }
 624
 625         /*
 626          * If we've successfully taken in some amount of
 627          * data, return success for that data first.  If
 628          * an error is persistent, it will be reported
 629          * on the next write.
 630          */
 631         if (error != 0 && write_len == 0)
 632                 return (error);
 633         if (write_len == 0 && uio->uio_resid != 0)
 634                 return (ENOSPC);
 635         return (0);
 636 }
 637
 638 /* Process requests (descrs) via the periph-supplied CCBs */
 639 static void
 640 targstart(struct cam_periph *periph, union ccb *start_ccb)
 641 {
 642         struct targ_softc *softc;
 643         struct targ_cmd_descr *descr, *next_descr;
 644         int error;
 645
 646         softc = (struct targ_softc *)periph->softc;
 647         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targstart %p\n", start_ccb));
 648
 649         crit_enter();
 650         descr = TAILQ_FIRST(&softc->work_queue);
 651         if (descr == NULL) {
 652                 crit_exit();
 653                 xpt_release_ccb(start_ccb);
 654         } else {
 655                 TAILQ_REMOVE(&softc->work_queue, descr, tqe);
 656                 next_descr = TAILQ_FIRST(&softc->work_queue);
 657                 crit_exit();
 658
 659                 /* Initiate a transaction using the descr and supplied CCB */
 660                 error = targusermerge(softc, descr, start_ccb);
 661                 if (error == 0)
 662                         error = targsendccb(softc, start_ccb, descr);
 663                 if (error != 0) {
 664                         xpt_print(periph->path,
 665                             "targsendccb failed, err %d\n", error);
 666                         xpt_release_ccb(start_ccb);
 667                         suword(&descr->user_ccb->ccb_h.status,
 668                                CAM_REQ_CMP_ERR);
 669                         crit_enter();
 670                         TAILQ_INSERT_TAIL(&softc->abort_queue, descr, tqe);
 671                         crit_exit();
 672                         notify_user(softc);
 673                 }
 674
 675                 /* If we have more work to do, stay scheduled */
 676                 if (next_descr != NULL)
 677                         xpt_schedule(periph, next_descr->priority);
 678         }
 679 }
 680
 681 static int
 682 targusermerge(struct targ_softc *softc, struct targ_cmd_descr *descr,
 683               union ccb *ccb)
 684 {
 685         struct ccb_hdr *u_ccbh, *k_ccbh;
 686         size_t ccb_len;
 687         int error;
 688
 689         u_ccbh = &descr->user_ccb->ccb_h;
 690         k_ccbh = &ccb->ccb_h;
 691
 692         /*
 693          * There are some fields in the CCB header that need to be
 694          * preserved, the rest we get from the user ccb. (See xpt_merge_ccb)
 695          */
 696         xpt_setup_ccb(k_ccbh, softc->path, descr->priority);
 697         k_ccbh->retry_count = fuword(&u_ccbh->retry_count);
 698         k_ccbh->func_code = descr->func_code;
 699         k_ccbh->flags = fuword(&u_ccbh->flags);
 700         k_ccbh->timeout = fuword(&u_ccbh->timeout);
 701         ccb_len = targccblen(k_ccbh->func_code) - sizeof(struct ccb_hdr);
 702         error = copyin(u_ccbh + 1, k_ccbh + 1, ccb_len);
 703         if (error != 0) {
 704                 k_ccbh->status = CAM_REQ_CMP_ERR;
 705                 return (error);
 706         }
 707
 708         /* Translate usermode abort_ccb pointer to its kernel counterpart */
 709         if (k_ccbh->func_code == XPT_ABORT) {
 710                 struct ccb_abort *cab;
 711                 struct ccb_hdr *ccb_h;
 712
 713                 cab = (struct ccb_abort *)ccb;
 714                 crit_enter();
 715                 TAILQ_FOREACH(ccb_h, &softc->pending_ccb_queue,
 716                     periph_links.tqe) {
 717                         struct targ_cmd_descr *ab_descr;
 718
 719                         ab_descr = (struct targ_cmd_descr *)ccb_h->targ_descr;
 720                         if (ab_descr->user_ccb == cab->abort_ccb) {
 721                                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 722                                           ("Changing abort for %p to %p\n",
 723                                           cab->abort_ccb, ccb_h));
 724                                 cab->abort_ccb = (union ccb *)ccb_h;
 725                                 break;
 726                         }
 727                 }
 728                 crit_exit();
 729                 /* CCB not found, set appropriate status */
 730                 if (ccb_h == NULL) {
 731                         k_ccbh->status = CAM_PATH_INVALID;
 732                         error = ESRCH;
 733                 }
 734         }
 735
 736         return (error);
 737 }
 738
 739 /* Build and send a kernel CCB formed from descr->user_ccb */
 740 static int
 741 targsendccb(struct targ_softc *softc, union ccb *ccb,
 742             struct targ_cmd_descr *descr)
 743 {
 744         struct cam_periph_map_info *mapinfo;
 745         struct ccb_hdr *ccb_h;
 746         int error;
 747
 748         ccb_h = &ccb->ccb_h;
 749         mapinfo = &descr->mapinfo;
 750         mapinfo->num_bufs_used = 0;
 751
 752         /*
 753          * There's no way for the user to have a completion
 754          * function, so we put our own completion function in here.
 755          * We also stash in a reference to our descriptor so targreturnccb()
 756          * can find our mapping info.
 757          */
 758         ccb_h->cbfcnp = targdone;
 759         ccb_h->targ_descr = descr;
 760
 761         /*
 762          * We only attempt to map the user memory into kernel space
 763          * if they haven't passed in a physical memory pointer,
 764          * and if there is actually an I/O operation to perform.
 765          * Right now cam_periph_mapmem() only supports SCSI and device
 766          * match CCBs.  For the SCSI CCBs, we only pass the CCB in if
 767          * there's actually data to map.  cam_periph_mapmem() will do the
 768          * right thing, even if there isn't data to map, but since CCBs
 769          * without data are a reasonably common occurance (e.g. test unit
 770          * ready), it will save a few cycles if we check for it here.
 771          */
 772         if (((ccb_h->flags & CAM_DATA_PHYS) == 0)
 773          && (((ccb_h->func_code == XPT_CONT_TARGET_IO)
 774             && ((ccb_h->flags & CAM_DIR_MASK) != CAM_DIR_NONE))
 775           || (ccb_h->func_code == XPT_DEV_MATCH))) {
 776
 777                 error = cam_periph_mapmem(ccb, mapinfo);
 778
 779                 /*
 780                  * cam_periph_mapmem returned an error, we can't continue.
 781                  * Return the error to the user.
 782                  */
 783                 if (error) {
 784                         ccb_h->status = CAM_REQ_CMP_ERR;
 785                         mapinfo->num_bufs_used = 0;
 786                         return (error);
 787                 }
 788         }
 789
 790         /*
 791          * Once queued on the pending CCB list, this CCB will be protected
 792          * by our error recovery handler.
 793          */
 794         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("sendccb %p\n", ccb));
 795         if (XPT_FC_IS_QUEUED(ccb)) {
 796                 crit_enter();
 797                 TAILQ_INSERT_TAIL(&softc->pending_ccb_queue, ccb_h,
 798                                   periph_links.tqe);
 799                 crit_exit();
 800         }
 801         xpt_action(ccb);
 802
 803         return (0);
 804 }
 805
 806 /* Completion routine for CCBs (called in a critical section) */
 807 static void
 808 targdone(struct cam_periph *periph, union ccb *done_ccb)
 809 {
 810         struct targ_softc *softc;
 811         cam_status status;
 812
 813         CAM_DEBUG(periph->path, CAM_DEBUG_PERIPH, ("targdone %p\n", done_ccb));
 814         softc = (struct targ_softc *)periph->softc;
 815         TAILQ_REMOVE(&softc->pending_ccb_queue, &done_ccb->ccb_h,
 816                      periph_links.tqe);
 817         status = done_ccb->ccb_h.status & CAM_STATUS_MASK;
 818
 819         /* If we're no longer enabled, throw away CCB */
 820         if ((softc->state & TARG_STATE_LUN_ENABLED) == 0) {
 821                 targfreeccb(softc, done_ccb);
 822                 return;
 823         }
 824         /* abort_all_pending() waits for pending queue to be empty */
 825         if (TAILQ_EMPTY(&softc->pending_ccb_queue))
 826                 wakeup(&softc->pending_ccb_queue);
 827
 828         switch (done_ccb->ccb_h.func_code) {
 829         /* All FC_*_QUEUED CCBs go back to userland */
 830         case XPT_IMMED_NOTIFY:
 831         case XPT_ACCEPT_TARGET_IO:
 832         case XPT_CONT_TARGET_IO:
 833                 TAILQ_INSERT_TAIL(&softc->user_ccb_queue, &done_ccb->ccb_h,
 834                                   periph_links.tqe);
 835                 notify_user(softc);
 836                 break;
 837         default:
 838                 panic("targdone: impossible xpt opcode %#x",
 839                       done_ccb->ccb_h.func_code);
 840                 /* NOTREACHED */
 841         }
 842 }
 843
 844 /* Return CCBs to the user from the user queue and abort queue */
 845 static int
 846 targread(struct dev_read_args *ap)
 847 {
 848         struct uio *uio = ap->a_uio;
 849         struct descr_queue      *abort_queue;
 850         struct targ_cmd_descr   *user_descr;
 851         struct targ_softc       *softc;
 852         struct ccb_queue  *user_queue;
 853         struct ccb_hdr    *ccb_h;
 854         union  ccb        *user_ccb;
 855         int                read_len, error;
 856
 857         error = 0;
 858         read_len = 0;
 859         softc = (struct targ_softc *)ap->a_head.a_dev->si_drv1;
 860         user_queue = &softc->user_ccb_queue;
 861         abort_queue = &softc->abort_queue;
 862         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targread\n"));
 863
 864         /* If no data is available, wait or return immediately */
 865         cam_periph_lock(softc->periph);
 866         ccb_h = TAILQ_FIRST(user_queue);
 867         user_descr = TAILQ_FIRST(abort_queue);
 868         while (ccb_h == NULL && user_descr == NULL) {
 869                 if ((ap->a_ioflag & IO_NDELAY) == 0) {
 870                         error = sim_lock_sleep(user_queue, PCATCH, "targrd", 0,
 871                                                softc->periph->sim->lock);
 872                         ccb_h = TAILQ_FIRST(user_queue);
 873                         user_descr = TAILQ_FIRST(abort_queue);
 874                         if (error != 0) {
 875                                 if (error == ERESTART) {
 876                                         continue;
 877                                 } else {
 878                                         goto read_fail;
 879                                 }
 880                         }
 881                 } else {
 882                         cam_periph_unlock(softc->periph);
 883                         return (EAGAIN);
 884                 }
 885         }
 886
 887         /* Data is available so fill the user's buffer */
 888         while (ccb_h != NULL) {
 889                 struct targ_cmd_descr *descr;
 890
 891                 if (uio->uio_resid < sizeof(user_ccb))
 892                         break;
 893                 TAILQ_REMOVE(user_queue, ccb_h, periph_links.tqe);
 894                 descr = (struct targ_cmd_descr *)ccb_h->targ_descr;
 895                 user_ccb = descr->user_ccb;
 896                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 897                           ("targread ccb %p (%p)\n", ccb_h, user_ccb));
 898                 error = targreturnccb(softc, (union ccb *)ccb_h);
 899                 if (error != 0)
 900                         goto read_fail;
 901                 cam_periph_unlock(softc->periph);
 902                 error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
 903                 cam_periph_lock(softc->periph);
 904                 if (error != 0)
 905                         goto read_fail;
 906                 read_len += sizeof(user_ccb);
 907
 908                 ccb_h = TAILQ_FIRST(user_queue);
 909         }
 910
 911         /* Flush out any aborted descriptors */
 912         while (user_descr != NULL) {
 913                 if (uio->uio_resid < sizeof(user_ccb))
 914                         break;
 915                 TAILQ_REMOVE(abort_queue, user_descr, tqe);
 916                 user_ccb = user_descr->user_ccb;
 917                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 918                           ("targread aborted descr %p (%p)\n",
 919                           user_descr, user_ccb));
 920                 suword(&user_ccb->ccb_h.status, CAM_REQ_ABORTED);
 921                 cam_periph_unlock(softc->periph);
 922                 error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
 923                 cam_periph_lock(softc->periph);
 924                 if (error != 0)
 925                         goto read_fail;
 926                 read_len += sizeof(user_ccb);
 927
 928                 user_descr = TAILQ_FIRST(abort_queue);
 929         }
 930
 931         /*
 932          * If we've successfully read some amount of data, don't report an
 933          * error.  If the error is persistent, it will be reported on the
 934          * next read().
 935          */
 936         if (read_len == 0 && uio->uio_resid != 0)
 937                 error = ENOSPC;
 938
 939 read_fail:
 940         cam_periph_unlock(softc->periph);
 941         return (error);
 942 }
 943
 944 /* Copy completed ccb back to the user */
 945 static int
 946 targreturnccb(struct targ_softc *softc, union ccb *ccb)
 947 {
 948         struct targ_cmd_descr *descr;
 949         struct ccb_hdr *u_ccbh;
 950         size_t ccb_len;
 951         int error;
 952
 953         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targreturnccb %p\n", ccb));
 954         descr = (struct targ_cmd_descr *)ccb->ccb_h.targ_descr;
 955         u_ccbh = &descr->user_ccb->ccb_h;
 956
 957         /* Copy out the central portion of the ccb_hdr */
 958         copyout(&ccb->ccb_h.retry_count, &u_ccbh->retry_count,
 959                 offsetof(struct ccb_hdr, periph_priv) -
 960                 offsetof(struct ccb_hdr, retry_count));
 961
 962         /* Copy out the rest of the ccb (after the ccb_hdr) */
 963         ccb_len = targccblen(ccb->ccb_h.func_code) - sizeof(struct ccb_hdr);
 964         if (descr->mapinfo.num_bufs_used != 0)
 965                 cam_periph_unmapmem(ccb, &descr->mapinfo);
 966         error = copyout(&ccb->ccb_h + 1, u_ccbh + 1, ccb_len);
 967         if (error != 0) {
 968                 xpt_print(softc->path,
 969                     "targreturnccb - CCB copyout failed (%d)\n", error);
 970         }
 971         /* Free CCB or send back to devq. */
 972         targfreeccb(softc, ccb);
 973
 974         return (error);
 975 }
 976
 977 static union ccb *
 978 targgetccb(struct targ_softc *softc, xpt_opcode type, int priority)
 979 {
 980         union ccb *ccb;
 981         int ccb_len;
 982
 983         ccb_len = targccblen(type);
 984         MALLOC(ccb, union ccb *, ccb_len, M_TARG, M_INTWAIT);
 985         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("getccb %p\n", ccb));
 986
 987         xpt_setup_ccb(&ccb->ccb_h, softc->path, priority);
 988         ccb->ccb_h.func_code = type;
 989         ccb->ccb_h.cbfcnp = targdone;
 990         ccb->ccb_h.targ_descr = targgetdescr(softc);
 991         return (ccb);
 992 }
 993
 994 static void
 995 targfreeccb(struct targ_softc *softc, union ccb *ccb)
 996 {
 997         CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH, ("targfreeccb descr %p and\n",
 998                         ccb->ccb_h.targ_descr));
 999         FREE(ccb->ccb_h.targ_descr, M_TARG);
1000
1001         switch (ccb->ccb_h.func_code) {
1002         case XPT_ACCEPT_TARGET_IO:
1003         case XPT_IMMED_NOTIFY:
1004                 CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH, ("freeing ccb %p\n", ccb));
1005                 FREE(ccb, M_TARG);
1006                 break;
1007         default:
1008                 /* Send back CCB if we got it from the periph */
1009                 if (XPT_FC_IS_QUEUED(ccb)) {
1010                         CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH,
1011                                         ("returning queued ccb %p\n", ccb));
1012                         xpt_release_ccb(ccb);
1013                 } else {
1014                         CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH,
1015                                         ("freeing ccb %p\n", ccb));
1016                         FREE(ccb, M_TARG);
1017                 }
1018                 break;
1019         }
1020 }
1021
1022 static struct targ_cmd_descr *
1023 targgetdescr(struct targ_softc *softc)
1024 {
1025         struct targ_cmd_descr *descr;
1026
1027         MALLOC(descr, struct targ_cmd_descr *, sizeof(*descr),
1028                 M_TARG, M_INTWAIT);
1029         descr->mapinfo.num_bufs_used = 0;
1030         return (descr);
1031 }
1032
1033 static int
1034 targclone(struct dev_clone_args *ap)
1035 {
1036         int unit;
1037
1038         unit = devfs_clone_bitmap_get(&DEVFS_CLONE_BITMAP(targ), 0);
1039         ap->a_dev = make_only_dev(&targ_ops, unit, UID_ROOT, GID_WHEEL,
1040                                   0600, "targ%d", unit);
1041         return 0;
1042 }
1043
1044 static void
1045 targinit(void)
1046 {
1047         make_autoclone_dev(&targ_ops, &DEVFS_CLONE_BITMAP(targ),
1048                 targclone, UID_ROOT, GID_WHEEL, 0600, "targ");
1049         /* XXX: need uninit or so? */
1050 }
1051
1052 static void
1053 targasync(void *callback_arg, u_int32_t code, struct cam_path *path, void *arg)
1054 {
1055         /* All events are handled in usermode by INOTs */
1056         panic("targasync() called, should be an INOT instead");
1057 }
1058
1059 /* Cancel all pending requests and CCBs awaiting work. */
1060 static void
1061 abort_all_pending(struct targ_softc *softc)
1062 {
1063         struct targ_cmd_descr   *descr;
1064         struct ccb_abort         cab;
1065         struct ccb_hdr          *ccb_h;
1066         struct cam_sim          *sim;
1067
1068         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("abort_all_pending\n"));
1069
1070         /* First abort the descriptors awaiting resources */
1071         while ((descr = TAILQ_FIRST(&softc->work_queue)) != NULL) {
1072                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
1073                           ("Aborting descr from workq %p\n", descr));
1074                 TAILQ_REMOVE(&softc->work_queue, descr, tqe);
1075                 TAILQ_INSERT_TAIL(&softc->abort_queue, descr, tqe);
1076         }
1077
1078         /*
1079          * Then abort all pending CCBs.
1080          * targdone() will return the aborted CCB via user_ccb_queue
1081          */
1082         xpt_setup_ccb(&cab.ccb_h, softc->path, /*priority*/0);
1083         cab.ccb_h.func_code = XPT_ABORT;
1084         cab.ccb_h.status = CAM_REQ_CMP_ERR;
1085         TAILQ_FOREACH(ccb_h, &softc->pending_ccb_queue, periph_links.tqe) {
1086                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
1087                           ("Aborting pending CCB %p\n", ccb_h));
1088                 cab.abort_ccb = (union ccb *)ccb_h;
1089                 xpt_action((union ccb *)&cab);
1090                 if (cab.ccb_h.status != CAM_REQ_CMP) {
1091                         xpt_print(cab.ccb_h.path,
1092                             "Unable to abort CCB, status %#x\n",
1093                             cab.ccb_h.status);
1094                 }
1095         }
1096
1097         /* If we aborted at least one pending CCB ok, wait for it. */
1098         if (cab.ccb_h.status == CAM_REQ_CMP) {
1099                 sim = xpt_path_sim(softc->path);
1100                 sim_lock_sleep(&softc->pending_ccb_queue, PCATCH, "tgabrt", 0,
1101                                sim->lock);
1102         }
1103
1104         /* If we aborted anything from the work queue, wakeup user. */
1105         if (!TAILQ_EMPTY(&softc->user_ccb_queue)
1106          || !TAILQ_EMPTY(&softc->abort_queue))
1107                 notify_user(softc);
1108 }
1109
1110 /* Notify the user that data is ready */
1111 static void
1112 notify_user(struct targ_softc *softc)
1113 {
1114         /*
1115          * Notify users sleeping via poll(), kqueue(), and
1116          * blocking read().
1117          */
1118         KNOTE(&softc->read_kq.ki_note, 0);
1119         wakeup(&softc->user_ccb_queue);
1120 }
1121
1122 /* Convert CAM status to errno values */
1123 static int
1124 targcamstatus(cam_status status)
1125 {
1126         switch (status & CAM_STATUS_MASK) {
1127         case CAM_REQ_CMP:       /* CCB request completed without error */
1128                 return (0);
1129         case CAM_REQ_INPROG:    /* CCB request is in progress */
1130                 return (EINPROGRESS);
1131         case CAM_REQ_CMP_ERR:   /* CCB request completed with an error */
1132                 return (EIO);
1133         case CAM_PROVIDE_FAIL:  /* Unable to provide requested capability */
1134                 return (ENOTTY);
1135         case CAM_FUNC_NOTAVAIL: /* The requested function is not available */
1136                 return (ENOTSUP);
1137         case CAM_LUN_ALRDY_ENA: /* LUN is already enabled for target mode */
1138                 return (EADDRINUSE);
1139         case CAM_PATH_INVALID:  /* Supplied Path ID is invalid */
1140         case CAM_DEV_NOT_THERE: /* SCSI Device Not Installed/there */
1141                 return (ENOENT);
1142         case CAM_REQ_ABORTED:   /* CCB request aborted by the host */
1143                 return (ECANCELED);
1144         case CAM_CMD_TIMEOUT:   /* Command timeout */
1145                 return (ETIMEDOUT);
1146         case CAM_REQUEUE_REQ:   /* Requeue to preserve transaction ordering */
1147                 return (EAGAIN);
1148         case CAM_REQ_INVALID:   /* CCB request was invalid */
1149                 return (EINVAL);
1150         case CAM_RESRC_UNAVAIL: /* Resource Unavailable */
1151                 return (ENOMEM);
1152         case CAM_BUSY:          /* CAM subsytem is busy */
1153         case CAM_UA_ABORT:      /* Unable to abort CCB request */
1154                 return (EBUSY);
1155         default:
1156                 return (ENXIO);
1157         }
1158 }
1159
1160 static size_t
1161 targccblen(xpt_opcode func_code)
1162 {
1163         int len;
1164
1165         /* Codes we expect to see as a target */
1166         switch (func_code) {
1167         case XPT_CONT_TARGET_IO:
1168         case XPT_SCSI_IO:
1169                 len = sizeof(struct ccb_scsiio);
1170                 break;
1171         case XPT_ACCEPT_TARGET_IO:
1172                 len = sizeof(struct ccb_accept_tio);
1173                 break;
1174         case XPT_IMMED_NOTIFY:
1175                 len = sizeof(struct ccb_immed_notify);
1176                 break;
1177         case XPT_REL_SIMQ:
1178                 len = sizeof(struct ccb_relsim);
1179                 break;
1180         case XPT_PATH_INQ:
1181                 len = sizeof(struct ccb_pathinq);
1182                 break;
1183         case XPT_DEBUG:
1184                 len = sizeof(struct ccb_debug);
1185                 break;
1186         case XPT_ABORT:
1187                 len = sizeof(struct ccb_abort);
1188                 break;
1189         case XPT_EN_LUN:
1190                 len = sizeof(struct ccb_en_lun);
1191                 break;
1192         default:
1193                 len = sizeof(union ccb);
1194                 break;
1195         }
1196
1197         return (len);
1198 }