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_DEFINE_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                 cdbg = &xpt_alloc_ccb()->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                 xpt_free_ccb(&cdbg->ccb_h);
 309 #else
 310                 status = CAM_FUNC_NOTAVAIL;
 311 #endif
 312                 break;
 313         }
 314         default:
 315                 status = CAM_PROVIDE_FAIL;
 316                 break;
 317         }
 318
 319         return (targcamstatus(status));
 320 }
 321
 322 static int
 323 targkqfilter(struct dev_kqfilter_args *ap)
 324 {
 325         struct  knote *kn = ap->a_kn;
 326         struct  targ_softc *softc;
 327
 328         softc = (struct targ_softc *)ap->a_head.a_dev->si_drv1;
 329
 330         ap->a_result = 0;
 331
 332         switch (kn->kn_filter) {
 333         case EVFILT_READ:
 334                 kn->kn_hook = (caddr_t)softc;
 335                 kn->kn_fop = &targread_filtops;
 336                 break;
 337         case EVFILT_WRITE:
 338                 kn->kn_hook = (caddr_t)softc;
 339                 kn->kn_fop = &targwrite_filtops;
 340         default:
 341                 ap->a_result = EOPNOTSUPP;
 342                 return (0);
 343         }
 344
 345         knote_insert(&softc->read_kq.ki_note, kn);
 346         return (0);
 347 }
 348
 349 static void
 350 targfiltdetach(struct knote *kn)
 351 {
 352         struct  targ_softc *softc;
 353
 354         softc = (struct targ_softc *)kn->kn_hook;
 355         knote_remove(&softc->read_kq.ki_note, kn);
 356 }
 357
 358 /* Notify the user's kqueue when the user queue or abort queue gets a CCB */
 359 static int
 360 targreadfilt(struct knote *kn, long hint)
 361 {
 362         struct targ_softc *softc;
 363         int     retval;
 364
 365         softc = (struct targ_softc *)kn->kn_hook;
 366         cam_periph_lock(softc->periph);
 367         retval = !TAILQ_EMPTY(&softc->user_ccb_queue) ||
 368                  !TAILQ_EMPTY(&softc->abort_queue);
 369         cam_periph_unlock(softc->periph);
 370         return (retval);
 371 }
 372
 373 /* write() is always ok */
 374 static int
 375 targwritefilt(struct knote *kn, long hint)
 376 {
 377         return (1);
 378 }
 379
 380 /* Send the HBA the enable/disable message */
 381 static cam_status
 382 targendislun(struct cam_path *path, int enable, int grp6_len, int grp7_len)
 383 {
 384         struct ccb_en_lun *en_ccb;
 385         cam_status        status;
 386
 387         /* Tell the lun to begin answering selects */
 388         en_ccb = &xpt_alloc_ccb()->cel;
 389         xpt_setup_ccb(&en_ccb->ccb_h, path, /*priority*/1);
 390         en_ccb->ccb_h.func_code = XPT_EN_LUN;
 391         /* Don't need support for any vendor specific commands */
 392         en_ccb->grp6_len = grp6_len;
 393         en_ccb->grp7_len = grp7_len;
 394         en_ccb->enable = enable ? 1 : 0;
 395         xpt_action((union ccb *)en_ccb);
 396         status = en_ccb->ccb_h.status & CAM_STATUS_MASK;
 397         if (status != CAM_REQ_CMP) {
 398                 xpt_print(path, "%sable lun CCB rejected, status %#x\n",
 399                     enable ? "en" : "dis", status);
 400         }
 401         xpt_free_ccb(&en_ccb->ccb_h);
 402
 403         return (status);
 404 }
 405
 406 /* Enable target mode on a LUN, given its path */
 407 static cam_status
 408 targenable(struct targ_softc *softc, struct cam_path *path, int grp6_len,
 409            int grp7_len)
 410 {
 411         struct cam_periph *periph;
 412         struct ccb_pathinq *cpi;
 413         cam_status         status;
 414
 415         if ((softc->state & TARG_STATE_LUN_ENABLED) != 0)
 416                 return (CAM_LUN_ALRDY_ENA);
 417
 418         /* Make sure SIM supports target mode */
 419         cpi = &xpt_alloc_ccb()->cpi;
 420         xpt_setup_ccb(&cpi->ccb_h, path, /*priority*/1);
 421         cpi->ccb_h.func_code = XPT_PATH_INQ;
 422         xpt_action((union ccb *)cpi);
 423         status = cpi->ccb_h.status & CAM_STATUS_MASK;
 424         if (status != CAM_REQ_CMP) {
 425                 kprintf("pathinq failed, status %#x\n", status);
 426                 goto enable_fail;
 427         }
 428         if ((cpi->target_sprt & PIT_PROCESSOR) == 0) {
 429                 kprintf("controller does not support target mode\n");
 430                 status = CAM_FUNC_NOTAVAIL;
 431                 goto enable_fail;
 432         }
 433
 434         /* Destroy any periph on our path if it is disabled */
 435         periph = cam_periph_find(path, "targ");
 436         if (periph != NULL) {
 437                 struct targ_softc *del_softc;
 438
 439                 del_softc = (struct targ_softc *)periph->softc;
 440                 if ((del_softc->state & TARG_STATE_LUN_ENABLED) == 0) {
 441                         cam_periph_invalidate(del_softc->periph);
 442                         del_softc->periph = NULL;
 443                 } else {
 444                         kprintf("Requested path still in use by targ%d\n",
 445                                periph->unit_number);
 446                         status = CAM_LUN_ALRDY_ENA;
 447                         goto enable_fail;
 448                 }
 449         }
 450
 451         /* Create a periph instance attached to this path */
 452         status = cam_periph_alloc(targctor, NULL, targdtor, targstart,
 453                         "targ", CAM_PERIPH_BIO, path, targasync, 0, softc);
 454         if (status != CAM_REQ_CMP) {
 455                 kprintf("cam_periph_alloc failed, status %#x\n", status);
 456                 goto enable_fail;
 457         }
 458
 459         /* Ensure that the periph now exists. */
 460         if (cam_periph_find(path, "targ") == NULL) {
 461                 panic("targenable: succeeded but no periph?");
 462                 /* NOTREACHED */
 463         }
 464
 465         /* Send the enable lun message */
 466         status = targendislun(path, /*enable*/1, grp6_len, grp7_len);
 467         if (status != CAM_REQ_CMP) {
 468                 kprintf("enable lun failed, status %#x\n", status);
 469                 goto enable_fail;
 470         }
 471         softc->state |= TARG_STATE_LUN_ENABLED;
 472
 473 enable_fail:
 474         xpt_free_ccb(&cpi->ccb_h);
 475
 476         return (status);
 477 }
 478
 479 /* Disable this softc's target instance if enabled */
 480 static cam_status
 481 targdisable(struct targ_softc *softc)
 482 {
 483         cam_status status;
 484
 485         if ((softc->state & TARG_STATE_LUN_ENABLED) == 0)
 486                 return (CAM_REQ_CMP);
 487
 488         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targdisable\n"));
 489
 490         /* Abort any ccbs pending on the controller */
 491         crit_enter();
 492         abort_all_pending(softc);
 493         crit_exit();
 494
 495         /* Disable this lun */
 496         status = targendislun(softc->path, /*enable*/0,
 497                               /*grp6_len*/0, /*grp7_len*/0);
 498         if (status == CAM_REQ_CMP)
 499                 softc->state &= ~TARG_STATE_LUN_ENABLED;
 500         else
 501                 kprintf("Disable lun failed, status %#x\n", status);
 502
 503         return (status);
 504 }
 505
 506 /* Initialize a periph (called from cam_periph_alloc) */
 507 static cam_status
 508 targctor(struct cam_periph *periph, void *arg)
 509 {
 510         struct targ_softc *softc;
 511
 512         /* Store pointer to softc for periph-driven routines */
 513         softc = (struct targ_softc *)arg;
 514         periph->softc = softc;
 515         softc->periph = periph;
 516         softc->path = periph->path;
 517         return (CAM_REQ_CMP);
 518 }
 519
 520 static void
 521 targdtor(struct cam_periph *periph)
 522 {
 523         struct targ_softc     *softc;
 524         struct ccb_hdr        *ccb_h;
 525         struct targ_cmd_descr *descr;
 526
 527         softc = (struct targ_softc *)periph->softc;
 528
 529         /*
 530          * targdisable() aborts CCBs back to the user and leaves them
 531          * on user_ccb_queue and abort_queue in case the user is still
 532          * interested in them.  We free them now.
 533          */
 534         while ((ccb_h = TAILQ_FIRST(&softc->user_ccb_queue)) != NULL) {
 535                 TAILQ_REMOVE(&softc->user_ccb_queue, ccb_h, periph_links.tqe);
 536                 targfreeccb(softc, (union ccb *)ccb_h);
 537         }
 538         while ((descr = TAILQ_FIRST(&softc->abort_queue)) != NULL) {
 539                 TAILQ_REMOVE(&softc->abort_queue, descr, tqe);
 540                 kfree(descr, M_TARG);
 541         }
 542
 543         softc->periph = NULL;
 544         softc->path = NULL;
 545         periph->softc = NULL;
 546 }
 547
 548 /* Receive CCBs from user mode proc and send them to the HBA */
 549 static int
 550 targwrite(struct dev_write_args *ap)
 551 {
 552         struct uio *uio = ap->a_uio;
 553         union ccb *user_ccb;
 554         struct targ_softc *softc;
 555         struct targ_cmd_descr *descr;
 556         int write_len, error;
 557         int func_code, priority;
 558
 559         softc = (struct targ_softc *)ap->a_head.a_dev->si_drv1;
 560         write_len = error = 0;
 561         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 562                   ("write - uio_resid %zu\n", uio->uio_resid));
 563         while (uio->uio_resid >= sizeof(user_ccb) && error == 0) {
 564                 union ccb *ccb;
 565
 566                 error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
 567                 if (error != 0) {
 568                         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 569                                   ("write - uiomove failed (%d)\n", error));
 570                         break;
 571                 }
 572                 priority = fuword32(&user_ccb->ccb_h.pinfo.priority);
 573                 if (priority == -1) {
 574                         error = EINVAL;
 575                         break;
 576                 }
 577                 func_code = fuword32(&user_ccb->ccb_h.func_code);
 578                 switch (func_code) {
 579                 case XPT_ACCEPT_TARGET_IO:
 580                 case XPT_IMMED_NOTIFY:
 581                         cam_periph_lock(softc->periph);
 582                         ccb = targgetccb(softc, func_code, priority);
 583                         descr = (struct targ_cmd_descr *)ccb->ccb_h.targ_descr;
 584                         descr->user_ccb = user_ccb;
 585                         descr->func_code = func_code;
 586                         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 587                                   ("Sent ATIO/INOT (%p)\n", user_ccb));
 588                         xpt_action(ccb);
 589                         TAILQ_INSERT_TAIL(&softc->pending_ccb_queue,
 590                                           &ccb->ccb_h,
 591                                           periph_links.tqe);
 592                         cam_periph_unlock(softc->periph);
 593                         break;
 594                 default:
 595                         cam_periph_lock(softc->periph);
 596                         if ((func_code & XPT_FC_QUEUED) != 0) {
 597                                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 598                                           ("Sending queued ccb %#x (%p)\n",
 599                                           func_code, user_ccb));
 600                                 descr = targgetdescr(softc);
 601                                 descr->user_ccb = user_ccb;
 602                                 descr->priority = priority;
 603                                 descr->func_code = func_code;
 604                                 crit_enter();
 605                                 TAILQ_INSERT_TAIL(&softc->work_queue,
 606                                                   descr, tqe);
 607                                 crit_exit();
 608                                 xpt_schedule(softc->periph, priority);
 609                         } else {
 610                                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 611                                           ("Sending inline ccb %#x (%p)\n",
 612                                           func_code, user_ccb));
 613                                 ccb = targgetccb(softc, func_code, priority);
 614                                 descr = (struct targ_cmd_descr *)
 615                                          ccb->ccb_h.targ_descr;
 616                                 descr->user_ccb = user_ccb;
 617                                 descr->priority = priority;
 618                                 descr->func_code = func_code;
 619                                 if (targusermerge(softc, descr, ccb) != EFAULT)
 620                                         targsendccb(softc, ccb, descr);
 621                                 targreturnccb(softc, ccb);
 622                         }
 623                         cam_periph_unlock(softc->periph);
 624                         break;
 625                 }
 626                 write_len += sizeof(user_ccb);
 627         }
 628
 629         /*
 630          * If we've successfully taken in some amount of
 631          * data, return success for that data first.  If
 632          * an error is persistent, it will be reported
 633          * on the next write.
 634          */
 635         if (error != 0 && write_len == 0)
 636                 return (error);
 637         if (write_len == 0 && uio->uio_resid != 0)
 638                 return (ENOSPC);
 639         return (0);
 640 }
 641
 642 /* Process requests (descrs) via the periph-supplied CCBs */
 643 static void
 644 targstart(struct cam_periph *periph, union ccb *start_ccb)
 645 {
 646         struct targ_softc *softc;
 647         struct targ_cmd_descr *descr, *next_descr;
 648         int error;
 649
 650         softc = (struct targ_softc *)periph->softc;
 651         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targstart %p\n", start_ccb));
 652
 653         crit_enter();
 654         descr = TAILQ_FIRST(&softc->work_queue);
 655         if (descr == NULL) {
 656                 crit_exit();
 657                 xpt_release_ccb(start_ccb);
 658         } else {
 659                 TAILQ_REMOVE(&softc->work_queue, descr, tqe);
 660                 next_descr = TAILQ_FIRST(&softc->work_queue);
 661                 crit_exit();
 662
 663                 /* Initiate a transaction using the descr and supplied CCB */
 664                 error = targusermerge(softc, descr, start_ccb);
 665                 if (error == 0)
 666                         error = targsendccb(softc, start_ccb, descr);
 667                 if (error != 0) {
 668                         xpt_print(periph->path,
 669                             "targsendccb failed, err %d\n", error);
 670                         xpt_release_ccb(start_ccb);
 671                         suword32(&descr->user_ccb->ccb_h.status,
 672                                  CAM_REQ_CMP_ERR);
 673                         crit_enter();
 674                         TAILQ_INSERT_TAIL(&softc->abort_queue, descr, tqe);
 675                         crit_exit();
 676                         notify_user(softc);
 677                 }
 678
 679                 /* If we have more work to do, stay scheduled */
 680                 if (next_descr != NULL)
 681                         xpt_schedule(periph, next_descr->priority);
 682         }
 683 }
 684
 685 static int
 686 targusermerge(struct targ_softc *softc, struct targ_cmd_descr *descr,
 687               union ccb *ccb)
 688 {
 689         struct ccb_hdr *u_ccbh, *k_ccbh;
 690         size_t ccb_len;
 691         int error;
 692
 693         u_ccbh = &descr->user_ccb->ccb_h;
 694         k_ccbh = &ccb->ccb_h;
 695
 696         /*
 697          * There are some fields in the CCB header that need to be
 698          * preserved, the rest we get from the user ccb. (See xpt_merge_ccb)
 699          */
 700         xpt_setup_ccb(k_ccbh, softc->path, descr->priority);
 701         k_ccbh->retry_count = fuword32(&u_ccbh->retry_count);
 702         k_ccbh->func_code = descr->func_code;
 703         k_ccbh->flags = fuword32(&u_ccbh->flags);
 704         k_ccbh->timeout = fuword32(&u_ccbh->timeout);
 705         ccb_len = targccblen(k_ccbh->func_code) - sizeof(struct ccb_hdr);
 706         error = copyin(u_ccbh + 1, k_ccbh + 1, ccb_len);
 707         if (error != 0) {
 708                 k_ccbh->status = CAM_REQ_CMP_ERR;
 709                 return (error);
 710         }
 711
 712         /* Translate usermode abort_ccb pointer to its kernel counterpart */
 713         if (k_ccbh->func_code == XPT_ABORT) {
 714                 struct ccb_abort *cab;
 715                 struct ccb_hdr *ccb_h;
 716
 717                 cab = (struct ccb_abort *)ccb;
 718                 crit_enter();
 719                 TAILQ_FOREACH(ccb_h, &softc->pending_ccb_queue,
 720                     periph_links.tqe) {
 721                         struct targ_cmd_descr *ab_descr;
 722
 723                         ab_descr = (struct targ_cmd_descr *)ccb_h->targ_descr;
 724                         if (ab_descr->user_ccb == cab->abort_ccb) {
 725                                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 726                                           ("Changing abort for %p to %p\n",
 727                                           cab->abort_ccb, ccb_h));
 728                                 cab->abort_ccb = (union ccb *)ccb_h;
 729                                 break;
 730                         }
 731                 }
 732                 crit_exit();
 733                 /* CCB not found, set appropriate status */
 734                 if (ccb_h == NULL) {
 735                         k_ccbh->status = CAM_PATH_INVALID;
 736                         error = ESRCH;
 737                 }
 738         }
 739
 740         return (error);
 741 }
 742
 743 /* Build and send a kernel CCB formed from descr->user_ccb */
 744 static int
 745 targsendccb(struct targ_softc *softc, union ccb *ccb,
 746             struct targ_cmd_descr *descr)
 747 {
 748         struct cam_periph_map_info *mapinfo;
 749         struct ccb_hdr *ccb_h;
 750         int error;
 751
 752         ccb_h = &ccb->ccb_h;
 753         mapinfo = &descr->mapinfo;
 754         mapinfo->num_bufs_used = 0;
 755
 756         /*
 757          * There's no way for the user to have a completion
 758          * function, so we put our own completion function in here.
 759          * We also stash in a reference to our descriptor so targreturnccb()
 760          * can find our mapping info.
 761          */
 762         ccb_h->cbfcnp = targdone;
 763         ccb_h->targ_descr = descr;
 764
 765         /*
 766          * We only attempt to map the user memory into kernel space
 767          * if they haven't passed in a physical memory pointer,
 768          * and if there is actually an I/O operation to perform.
 769          * Right now cam_periph_mapmem() only supports SCSI and device
 770          * match CCBs.  For the SCSI CCBs, we only pass the CCB in if
 771          * there's actually data to map.  cam_periph_mapmem() will do the
 772          * right thing, even if there isn't data to map, but since CCBs
 773          * without data are a reasonably common occurance (e.g. test unit
 774          * ready), it will save a few cycles if we check for it here.
 775          */
 776         if (((ccb_h->flags & CAM_DATA_PHYS) == 0)
 777          && (((ccb_h->func_code == XPT_CONT_TARGET_IO)
 778             && ((ccb_h->flags & CAM_DIR_MASK) != CAM_DIR_NONE))
 779           || (ccb_h->func_code == XPT_DEV_MATCH))) {
 780
 781                 error = cam_periph_mapmem(ccb, mapinfo);
 782
 783                 /*
 784                  * cam_periph_mapmem returned an error, we can't continue.
 785                  * Return the error to the user.
 786                  */
 787                 if (error) {
 788                         ccb_h->status = CAM_REQ_CMP_ERR;
 789                         mapinfo->num_bufs_used = 0;
 790                         return (error);
 791                 }
 792         }
 793
 794         /*
 795          * Once queued on the pending CCB list, this CCB will be protected
 796          * by our error recovery handler.
 797          */
 798         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("sendccb %p\n", ccb));
 799         if (XPT_FC_IS_QUEUED(ccb)) {
 800                 crit_enter();
 801                 TAILQ_INSERT_TAIL(&softc->pending_ccb_queue, ccb_h,
 802                                   periph_links.tqe);
 803                 crit_exit();
 804         }
 805         xpt_action(ccb);
 806
 807         return (0);
 808 }
 809
 810 /* Completion routine for CCBs (called in a critical section) */
 811 static void
 812 targdone(struct cam_periph *periph, union ccb *done_ccb)
 813 {
 814         struct targ_softc *softc;
 815
 816         CAM_DEBUG(periph->path, CAM_DEBUG_PERIPH, ("targdone %p\n", done_ccb));
 817         softc = (struct targ_softc *)periph->softc;
 818         TAILQ_REMOVE(&softc->pending_ccb_queue, &done_ccb->ccb_h,
 819                      periph_links.tqe);
 820
 821         /* If we're no longer enabled, throw away CCB */
 822         if ((softc->state & TARG_STATE_LUN_ENABLED) == 0) {
 823                 targfreeccb(softc, done_ccb);
 824                 return;
 825         }
 826         /* abort_all_pending() waits for pending queue to be empty */
 827         if (TAILQ_EMPTY(&softc->pending_ccb_queue))
 828                 wakeup(&softc->pending_ccb_queue);
 829
 830         switch (done_ccb->ccb_h.func_code) {
 831         /* All FC_*_QUEUED CCBs go back to userland */
 832         case XPT_IMMED_NOTIFY:
 833         case XPT_ACCEPT_TARGET_IO:
 834         case XPT_CONT_TARGET_IO:
 835                 TAILQ_INSERT_TAIL(&softc->user_ccb_queue, &done_ccb->ccb_h,
 836                                   periph_links.tqe);
 837                 notify_user(softc);
 838                 break;
 839         default:
 840                 panic("targdone: impossible xpt opcode %#x",
 841                       done_ccb->ccb_h.func_code);
 842                 /* NOTREACHED */
 843         }
 844 }
 845
 846 /* Return CCBs to the user from the user queue and abort queue */
 847 static int
 848 targread(struct dev_read_args *ap)
 849 {
 850         struct uio *uio = ap->a_uio;
 851         struct descr_queue      *abort_queue;
 852         struct targ_cmd_descr   *user_descr;
 853         struct targ_softc       *softc;
 854         struct ccb_queue  *user_queue;
 855         struct ccb_hdr    *ccb_h;
 856         union  ccb        *user_ccb;
 857         int                read_len, error;
 858
 859         error = 0;
 860         read_len = 0;
 861         softc = (struct targ_softc *)ap->a_head.a_dev->si_drv1;
 862         user_queue = &softc->user_ccb_queue;
 863         abort_queue = &softc->abort_queue;
 864         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targread\n"));
 865
 866         /* If no data is available, wait or return immediately */
 867         cam_periph_lock(softc->periph);
 868         ccb_h = TAILQ_FIRST(user_queue);
 869         user_descr = TAILQ_FIRST(abort_queue);
 870         while (ccb_h == NULL && user_descr == NULL) {
 871                 if ((ap->a_ioflag & IO_NDELAY) == 0) {
 872                         error = sim_lock_sleep(user_queue, PCATCH, "targrd", 0,
 873                                                softc->periph->sim->lock);
 874                         ccb_h = TAILQ_FIRST(user_queue);
 875                         user_descr = TAILQ_FIRST(abort_queue);
 876                         if (error != 0) {
 877                                 if (error == ERESTART) {
 878                                         continue;
 879                                 } else {
 880                                         goto read_fail;
 881                                 }
 882                         }
 883                 } else {
 884                         cam_periph_unlock(softc->periph);
 885                         return (EAGAIN);
 886                 }
 887         }
 888
 889         /* Data is available so fill the user's buffer */
 890         while (ccb_h != NULL) {
 891                 struct targ_cmd_descr *descr;
 892
 893                 if (uio->uio_resid < sizeof(user_ccb))
 894                         break;
 895                 TAILQ_REMOVE(user_queue, ccb_h, periph_links.tqe);
 896                 descr = (struct targ_cmd_descr *)ccb_h->targ_descr;
 897                 user_ccb = descr->user_ccb;
 898                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 899                           ("targread ccb %p (%p)\n", ccb_h, user_ccb));
 900                 error = targreturnccb(softc, (union ccb *)ccb_h);
 901                 if (error != 0)
 902                         goto read_fail;
 903                 cam_periph_unlock(softc->periph);
 904                 error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
 905                 cam_periph_lock(softc->periph);
 906                 if (error != 0)
 907                         goto read_fail;
 908                 read_len += sizeof(user_ccb);
 909
 910                 ccb_h = TAILQ_FIRST(user_queue);
 911         }
 912
 913         /* Flush out any aborted descriptors */
 914         while (user_descr != NULL) {
 915                 if (uio->uio_resid < sizeof(user_ccb))
 916                         break;
 917                 TAILQ_REMOVE(abort_queue, user_descr, tqe);
 918                 user_ccb = user_descr->user_ccb;
 919                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 920                           ("targread aborted descr %p (%p)\n",
 921                           user_descr, user_ccb));
 922                 suword32(&user_ccb->ccb_h.status, CAM_REQ_ABORTED);
 923                 cam_periph_unlock(softc->periph);
 924                 error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
 925                 cam_periph_lock(softc->periph);
 926                 if (error != 0)
 927                         goto read_fail;
 928                 read_len += sizeof(user_ccb);
 929
 930                 user_descr = TAILQ_FIRST(abort_queue);
 931         }
 932
 933         /*
 934          * If we've successfully read some amount of data, don't report an
 935          * error.  If the error is persistent, it will be reported on the
 936          * next read().
 937          */
 938         if (read_len == 0 && uio->uio_resid != 0)
 939                 error = ENOSPC;
 940
 941 read_fail:
 942         cam_periph_unlock(softc->periph);
 943         return (error);
 944 }
 945
 946 /* Copy completed ccb back to the user */
 947 static int
 948 targreturnccb(struct targ_softc *softc, union ccb *ccb)
 949 {
 950         struct targ_cmd_descr *descr;
 951         struct ccb_hdr *u_ccbh;
 952         size_t ccb_len;
 953         int error;
 954
 955         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targreturnccb %p\n", ccb));
 956         descr = (struct targ_cmd_descr *)ccb->ccb_h.targ_descr;
 957         u_ccbh = &descr->user_ccb->ccb_h;
 958
 959         /* Copy out the central portion of the ccb_hdr */
 960         copyout(&ccb->ccb_h.retry_count, &u_ccbh->retry_count,
 961                 offsetof(struct ccb_hdr, periph_priv) -
 962                 offsetof(struct ccb_hdr, retry_count));
 963
 964         /* Copy out the rest of the ccb (after the ccb_hdr) */
 965         ccb_len = targccblen(ccb->ccb_h.func_code) - sizeof(struct ccb_hdr);
 966         if (descr->mapinfo.num_bufs_used != 0)
 967                 cam_periph_unmapmem(ccb, &descr->mapinfo);
 968         error = copyout(&ccb->ccb_h + 1, u_ccbh + 1, ccb_len);
 969         if (error != 0) {
 970                 xpt_print(softc->path,
 971                     "targreturnccb - CCB copyout failed (%d)\n", error);
 972         }
 973         /* Free CCB or send back to devq. */
 974         targfreeccb(softc, ccb);
 975
 976         return (error);
 977 }
 978
 979 static union ccb *
 980 targgetccb(struct targ_softc *softc, xpt_opcode type, int priority)
 981 {
 982         union ccb *ccb;
 983
 984 #if 0
 985         int ccb_len;
 986         ccb_len = targccblen(type);
 987         ccb = kmalloc(ccb_len, M_TARG, M_INTWAIT);
 988 #endif
 989         ccb = xpt_alloc_ccb();
 990         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("getccb %p\n", ccb));
 991
 992         xpt_setup_ccb(&ccb->ccb_h, softc->path, priority);
 993         ccb->ccb_h.func_code = type;
 994         ccb->ccb_h.cbfcnp = targdone;
 995         ccb->ccb_h.targ_descr = targgetdescr(softc);
 996
 997         return (ccb);
 998 }
 999
1000 static void
1001 targfreeccb(struct targ_softc *softc, union ccb *ccb)
1002 {
1003         CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH, ("targfreeccb descr %p and\n",
1004                         ccb->ccb_h.targ_descr));
1005         kfree(ccb->ccb_h.targ_descr, M_TARG);
1006         ccb->ccb_h.targ_descr = NULL;   /* safety */
1007
1008         switch (ccb->ccb_h.func_code) {
1009         case XPT_ACCEPT_TARGET_IO:
1010         case XPT_IMMED_NOTIFY:
1011                 CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH, ("freeing ccb %p\n", ccb));
1012                 xpt_free_ccb(&ccb->ccb_h);
1013                 break;
1014         default:
1015                 /* Send back CCB if we got it from the periph */
1016                 if (XPT_FC_IS_QUEUED(ccb)) {
1017                         CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH,
1018                                         ("returning queued ccb %p\n", ccb));
1019                         xpt_release_ccb(ccb);
1020                 } else {
1021                         CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH,
1022                                         ("freeing ccb %p\n", ccb));
1023                         xpt_free_ccb(&ccb->ccb_h);
1024                 }
1025                 break;
1026         }
1027 }
1028
1029 static struct targ_cmd_descr *
1030 targgetdescr(struct targ_softc *softc)
1031 {
1032         struct targ_cmd_descr *descr;
1033
1034         descr = kmalloc(sizeof(*descr), M_TARG, M_INTWAIT);
1035         descr->mapinfo.num_bufs_used = 0;
1036         return (descr);
1037 }
1038
1039 static int
1040 targclone(struct dev_clone_args *ap)
1041 {
1042         int unit;
1043
1044         unit = devfs_clone_bitmap_get(&DEVFS_CLONE_BITMAP(targ), 0);
1045         ap->a_dev = make_only_dev(&targ_ops, unit, UID_ROOT, GID_WHEEL,
1046                                   0600, "targ%d", unit);
1047         return 0;
1048 }
1049
1050 static void
1051 targinit(void)
1052 {
1053         make_autoclone_dev(&targ_ops, &DEVFS_CLONE_BITMAP(targ),
1054                 targclone, UID_ROOT, GID_WHEEL, 0600, "targ");
1055         /* XXX: need uninit or so? */
1056 }
1057
1058 static void
1059 targasync(void *callback_arg, u_int32_t code, struct cam_path *path, void *arg)
1060 {
1061         /* All events are handled in usermode by INOTs */
1062         panic("targasync() called, should be an INOT instead");
1063 }
1064
1065 /* Cancel all pending requests and CCBs awaiting work. */
1066 static void
1067 abort_all_pending(struct targ_softc *softc)
1068 {
1069         struct targ_cmd_descr   *descr;
1070         struct ccb_abort         *cab;
1071         struct ccb_hdr          *ccb_h;
1072         struct cam_sim          *sim;
1073
1074         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("abort_all_pending\n"));
1075
1076         /* First abort the descriptors awaiting resources */
1077         while ((descr = TAILQ_FIRST(&softc->work_queue)) != NULL) {
1078                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
1079                           ("Aborting descr from workq %p\n", descr));
1080                 TAILQ_REMOVE(&softc->work_queue, descr, tqe);
1081                 TAILQ_INSERT_TAIL(&softc->abort_queue, descr, tqe);
1082         }
1083
1084         /*
1085          * Then abort all pending CCBs.
1086          * targdone() will return the aborted CCB via user_ccb_queue
1087          */
1088         cab = &xpt_alloc_ccb()->cab;
1089         xpt_setup_ccb(&cab->ccb_h, softc->path, /*priority*/0);
1090         cab->ccb_h.func_code = XPT_ABORT;
1091         cab->ccb_h.status = CAM_REQ_CMP_ERR;
1092         TAILQ_FOREACH(ccb_h, &softc->pending_ccb_queue, periph_links.tqe) {
1093                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
1094                           ("Aborting pending CCB %p\n", ccb_h));
1095                 cab->abort_ccb = (union ccb *)ccb_h;
1096                 xpt_action((union ccb *)cab);
1097                 if (cab->ccb_h.status != CAM_REQ_CMP) {
1098                         xpt_print(cab->ccb_h.path,
1099                             "Unable to abort CCB, status %#x\n",
1100                             cab->ccb_h.status);
1101                 }
1102         }
1103
1104         /* If we aborted at least one pending CCB ok, wait for it. */
1105         if (cab->ccb_h.status == CAM_REQ_CMP) {
1106                 sim = xpt_path_sim(softc->path);
1107                 sim_lock_sleep(&softc->pending_ccb_queue, PCATCH, "tgabrt", 0,
1108                                sim->lock);
1109         }
1110
1111         /* If we aborted anything from the work queue, wakeup user. */
1112         if (!TAILQ_EMPTY(&softc->user_ccb_queue) ||
1113             !TAILQ_EMPTY(&softc->abort_queue)) {
1114                 notify_user(softc);
1115         }
1116
1117         xpt_free_ccb(&cab->ccb_h);
1118 }
1119
1120 /* Notify the user that data is ready */
1121 static void
1122 notify_user(struct targ_softc *softc)
1123 {
1124         /*
1125          * Notify users sleeping via poll(), kqueue(), and
1126          * blocking read().
1127          */
1128         KNOTE(&softc->read_kq.ki_note, 0);
1129         wakeup(&softc->user_ccb_queue);
1130 }
1131
1132 /* Convert CAM status to errno values */
1133 static int
1134 targcamstatus(cam_status status)
1135 {
1136         switch (status & CAM_STATUS_MASK) {
1137         case CAM_REQ_CMP:       /* CCB request completed without error */
1138                 return (0);
1139         case CAM_REQ_INPROG:    /* CCB request is in progress */
1140                 return (EINPROGRESS);
1141         case CAM_REQ_CMP_ERR:   /* CCB request completed with an error */
1142                 return (EIO);
1143         case CAM_PROVIDE_FAIL:  /* Unable to provide requested capability */
1144                 return (ENOTTY);
1145         case CAM_FUNC_NOTAVAIL: /* The requested function is not available */
1146                 return (ENOTSUP);
1147         case CAM_LUN_ALRDY_ENA: /* LUN is already enabled for target mode */
1148                 return (EADDRINUSE);
1149         case CAM_PATH_INVALID:  /* Supplied Path ID is invalid */
1150         case CAM_DEV_NOT_THERE: /* SCSI Device Not Installed/there */
1151                 return (ENOENT);
1152         case CAM_REQ_ABORTED:   /* CCB request aborted by the host */
1153                 return (ECANCELED);
1154         case CAM_CMD_TIMEOUT:   /* Command timeout */
1155                 return (ETIMEDOUT);
1156         case CAM_REQUEUE_REQ:   /* Requeue to preserve transaction ordering */
1157                 return (EAGAIN);
1158         case CAM_REQ_INVALID:   /* CCB request was invalid */
1159                 return (EINVAL);
1160         case CAM_RESRC_UNAVAIL: /* Resource Unavailable */
1161                 return (ENOMEM);
1162         case CAM_BUSY:          /* CAM subsytem is busy */
1163         case CAM_UA_ABORT:      /* Unable to abort CCB request */
1164                 return (EBUSY);
1165         default:
1166                 return (ENXIO);
1167         }
1168 }
1169
1170 static size_t
1171 targccblen(xpt_opcode func_code)
1172 {
1173         int len;
1174
1175         /* Codes we expect to see as a target */
1176         switch (func_code) {
1177         case XPT_CONT_TARGET_IO:
1178         case XPT_SCSI_IO:
1179                 len = sizeof(struct ccb_scsiio);
1180                 break;
1181         case XPT_ACCEPT_TARGET_IO:
1182                 len = sizeof(struct ccb_accept_tio);
1183                 break;
1184         case XPT_IMMED_NOTIFY:
1185                 len = sizeof(struct ccb_immed_notify);
1186                 break;
1187         case XPT_REL_SIMQ:
1188                 len = sizeof(struct ccb_relsim);
1189                 break;
1190         case XPT_PATH_INQ:
1191                 len = sizeof(struct ccb_pathinq);
1192                 break;
1193         case XPT_DEBUG:
1194                 len = sizeof(struct ccb_debug);
1195                 break;
1196         case XPT_ABORT:
1197                 len = sizeof(struct ccb_abort);
1198                 break;
1199         case XPT_EN_LUN:
1200                 len = sizeof(struct ccb_en_lun);
1201                 break;
1202         default:
1203                 len = sizeof(union ccb);
1204                 break;
1205         }
1206
1207         return (len);
1208 }