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/poll.h>
  40 #include <sys/vnode.h>
  41 #include <sys/devicestat.h>
  42 #include <sys/thread2.h>
  43 #include <sys/devfs.h>
  44
  45 #include "../cam.h"
  46 #include "../cam_ccb.h"
  47 #include "../cam_periph.h"
  48 #include "../cam_xpt_periph.h"
  49 #include "../cam_sim.h"
  50 #include "scsi_targetio.h"
  51
  52 /* Transaction information attached to each CCB sent by the user */
  53 struct targ_cmd_descr {
  54         struct cam_periph_map_info  mapinfo;
  55         TAILQ_ENTRY(targ_cmd_descr) tqe;
  56         union ccb *user_ccb;
  57         int        priority;
  58         int        func_code;
  59 };
  60
  61 /* Offset into the private CCB area for storing our descriptor */
  62 #define targ_descr      periph_priv.entries[1].ptr
  63
  64 TAILQ_HEAD(descr_queue, targ_cmd_descr);
  65
  66 typedef enum {
  67         TARG_STATE_RESV         = 0x00, /* Invalid state */
  68         TARG_STATE_OPENED       = 0x01, /* Device opened, softc initialized */
  69         TARG_STATE_LUN_ENABLED  = 0x02  /* Device enabled for a path */
  70 } targ_state;
  71
  72 /* Per-instance device software context */
  73 struct targ_softc {
  74         /* CCBs (CTIOs, ATIOs, INOTs) pending on the controller */
  75         struct ccb_queue         pending_ccb_queue;
  76
  77         /* Command descriptors awaiting CTIO resources from the XPT */
  78         struct descr_queue       work_queue;
  79
  80         /* Command descriptors that have been aborted back to the user. */
  81         struct descr_queue       abort_queue;
  82
  83         /*
  84          * Queue of CCBs that have been copied out to userland, but our
  85          * userland daemon has not yet seen.
  86          */
  87         struct ccb_queue         user_ccb_queue;
  88
  89         struct cam_periph       *periph;
  90         struct cam_path         *path;
  91         targ_state               state;
  92         struct selinfo           read_select;
  93         struct devstat           device_stats;
  94 };
  95
  96 static d_open_t         targopen;
  97 static d_close_t        targclose;
  98 static d_read_t         targread;
  99 static d_write_t        targwrite;
 100 static d_ioctl_t        targioctl;
 101 static d_poll_t         targpoll;
 102 static d_kqfilter_t     targkqfilter;
 103 static d_clone_t        targclone;
 104 DEVFS_DECLARE_CLONE_BITMAP(targ);
 105
 106 static void             targreadfiltdetach(struct knote *kn);
 107 static int              targreadfilt(struct knote *kn, long hint);
 108 static struct filterops targread_filtops =
 109         { 1, NULL, targreadfiltdetach, targreadfilt };
 110
 111 #define TARG_CDEV_MAJOR 65
 112 static struct dev_ops targ_ops = {
 113         { "targ", TARG_CDEV_MAJOR, D_KQFILTER },
 114         .d_open = targopen,
 115         .d_close = targclose,
 116         .d_read = targread,
 117         .d_write = targwrite,
 118         .d_ioctl = targioctl,
 119         .d_poll = targpoll,
 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 /* Writes are always ready, reads wait for user_ccb_queue or abort_queue */
 325 static int
 326 targpoll(struct dev_poll_args *ap)
 327 {
 328         struct targ_softc *softc;
 329         int     revents;
 330
 331         softc = (struct targ_softc *)ap->a_head.a_dev->si_drv1;
 332
 333         /* Poll for write() is always ok. */
 334         revents = ap->a_events & (POLLOUT | POLLWRNORM);
 335         if ((ap->a_events & (POLLIN | POLLRDNORM)) != 0) {
 336                 /* Poll for read() depends on user and abort queues. */
 337                 cam_periph_lock(softc->periph);
 338                 if (!TAILQ_EMPTY(&softc->user_ccb_queue) ||
 339                     !TAILQ_EMPTY(&softc->abort_queue)) {
 340                         revents |= ap->a_events & (POLLIN | POLLRDNORM);
 341                 }
 342                 cam_periph_unlock(softc->periph);
 343                 /* Only sleep if the user didn't poll for write. */
 344                 if (revents == 0)
 345                         selrecord(curthread, &softc->read_select);
 346         }
 347         ap->a_events = revents;
 348         return (0);
 349 }
 350
 351 static int
 352 targkqfilter(struct dev_kqfilter_args *ap)
 353 {
 354         struct  knote *kn = ap->a_kn;
 355         struct  targ_softc *softc;
 356
 357         softc = (struct targ_softc *)ap->a_head.a_dev->si_drv1;
 358         kn->kn_hook = (caddr_t)softc;
 359         kn->kn_fop = &targread_filtops;
 360         crit_enter();
 361         SLIST_INSERT_HEAD(&softc->read_select.si_note, kn, kn_selnext);
 362         crit_exit();
 363         return (0);
 364 }
 365
 366 static void
 367 targreadfiltdetach(struct knote *kn)
 368 {
 369         struct  targ_softc *softc;
 370
 371         softc = (struct targ_softc *)kn->kn_hook;
 372         crit_enter();
 373         SLIST_REMOVE(&softc->read_select.si_note, kn, knote, kn_selnext);
 374         crit_exit();
 375 }
 376
 377 /* Notify the user's kqueue when the user queue or abort queue gets a CCB */
 378 static int
 379 targreadfilt(struct knote *kn, long hint)
 380 {
 381         struct targ_softc *softc;
 382         int     retval;
 383
 384         softc = (struct targ_softc *)kn->kn_hook;
 385         cam_periph_lock(softc->periph);
 386         retval = !TAILQ_EMPTY(&softc->user_ccb_queue) ||
 387                  !TAILQ_EMPTY(&softc->abort_queue);
 388         cam_periph_unlock(softc->periph);
 389         return (retval);
 390 }
 391
 392 /* Send the HBA the enable/disable message */
 393 static cam_status
 394 targendislun(struct cam_path *path, int enable, int grp6_len, int grp7_len)
 395 {
 396         struct ccb_en_lun en_ccb;
 397         cam_status        status;
 398
 399         /* Tell the lun to begin answering selects */
 400         xpt_setup_ccb(&en_ccb.ccb_h, path, /*priority*/1);
 401         en_ccb.ccb_h.func_code = XPT_EN_LUN;
 402         /* Don't need support for any vendor specific commands */
 403         en_ccb.grp6_len = grp6_len;
 404         en_ccb.grp7_len = grp7_len;
 405         en_ccb.enable = enable ? 1 : 0;
 406         xpt_action((union ccb *)&en_ccb);
 407         status = en_ccb.ccb_h.status & CAM_STATUS_MASK;
 408         if (status != CAM_REQ_CMP) {
 409                 xpt_print(path, "%sable lun CCB rejected, status %#x\n",
 410                     enable ? "en" : "dis", status);
 411         }
 412         return (status);
 413 }
 414
 415 /* Enable target mode on a LUN, given its path */
 416 static cam_status
 417 targenable(struct targ_softc *softc, struct cam_path *path, int grp6_len,
 418            int grp7_len)
 419 {
 420         struct cam_periph *periph;
 421         struct ccb_pathinq cpi;
 422         cam_status         status;
 423
 424         if ((softc->state & TARG_STATE_LUN_ENABLED) != 0)
 425                 return (CAM_LUN_ALRDY_ENA);
 426
 427         /* Make sure SIM supports target mode */
 428         xpt_setup_ccb(&cpi.ccb_h, path, /*priority*/1);
 429         cpi.ccb_h.func_code = XPT_PATH_INQ;
 430         xpt_action((union ccb *)&cpi);
 431         status = cpi.ccb_h.status & CAM_STATUS_MASK;
 432         if (status != CAM_REQ_CMP) {
 433                 kprintf("pathinq failed, status %#x\n", status);
 434                 goto enable_fail;
 435         }
 436         if ((cpi.target_sprt & PIT_PROCESSOR) == 0) {
 437                 kprintf("controller does not support target mode\n");
 438                 status = CAM_FUNC_NOTAVAIL;
 439                 goto enable_fail;
 440         }
 441
 442         /* Destroy any periph on our path if it is disabled */
 443         periph = cam_periph_find(path, "targ");
 444         if (periph != NULL) {
 445                 struct targ_softc *del_softc;
 446
 447                 del_softc = (struct targ_softc *)periph->softc;
 448                 if ((del_softc->state & TARG_STATE_LUN_ENABLED) == 0) {
 449                         cam_periph_invalidate(del_softc->periph);
 450                         del_softc->periph = NULL;
 451                 } else {
 452                         kprintf("Requested path still in use by targ%d\n",
 453                                periph->unit_number);
 454                         status = CAM_LUN_ALRDY_ENA;
 455                         goto enable_fail;
 456                 }
 457         }
 458
 459         /* Create a periph instance attached to this path */
 460         status = cam_periph_alloc(targctor, NULL, targdtor, targstart,
 461                         "targ", CAM_PERIPH_BIO, path, targasync, 0, softc);
 462         if (status != CAM_REQ_CMP) {
 463                 kprintf("cam_periph_alloc failed, status %#x\n", status);
 464                 goto enable_fail;
 465         }
 466
 467         /* Ensure that the periph now exists. */
 468         if (cam_periph_find(path, "targ") == NULL) {
 469                 panic("targenable: succeeded but no periph?");
 470                 /* NOTREACHED */
 471         }
 472
 473         /* Send the enable lun message */
 474         status = targendislun(path, /*enable*/1, grp6_len, grp7_len);
 475         if (status != CAM_REQ_CMP) {
 476                 kprintf("enable lun failed, status %#x\n", status);
 477                 goto enable_fail;
 478         }
 479         softc->state |= TARG_STATE_LUN_ENABLED;
 480
 481 enable_fail:
 482         return (status);
 483 }
 484
 485 /* Disable this softc's target instance if enabled */
 486 static cam_status
 487 targdisable(struct targ_softc *softc)
 488 {
 489         cam_status status;
 490
 491         if ((softc->state & TARG_STATE_LUN_ENABLED) == 0)
 492                 return (CAM_REQ_CMP);
 493
 494         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targdisable\n"));
 495
 496         /* Abort any ccbs pending on the controller */
 497         crit_enter();
 498         abort_all_pending(softc);
 499         crit_exit();
 500
 501         /* Disable this lun */
 502         status = targendislun(softc->path, /*enable*/0,
 503                               /*grp6_len*/0, /*grp7_len*/0);
 504         if (status == CAM_REQ_CMP)
 505                 softc->state &= ~TARG_STATE_LUN_ENABLED;
 506         else
 507                 kprintf("Disable lun failed, status %#x\n", status);
 508
 509         return (status);
 510 }
 511
 512 /* Initialize a periph (called from cam_periph_alloc) */
 513 static cam_status
 514 targctor(struct cam_periph *periph, void *arg)
 515 {
 516         struct targ_softc *softc;
 517
 518         /* Store pointer to softc for periph-driven routines */
 519         softc = (struct targ_softc *)arg;
 520         periph->softc = softc;
 521         softc->periph = periph;
 522         softc->path = periph->path;
 523         return (CAM_REQ_CMP);
 524 }
 525
 526 static void
 527 targdtor(struct cam_periph *periph)
 528 {
 529         struct targ_softc     *softc;
 530         struct ccb_hdr        *ccb_h;
 531         struct targ_cmd_descr *descr;
 532
 533         softc = (struct targ_softc *)periph->softc;
 534
 535         /*
 536          * targdisable() aborts CCBs back to the user and leaves them
 537          * on user_ccb_queue and abort_queue in case the user is still
 538          * interested in them.  We free them now.
 539          */
 540         while ((ccb_h = TAILQ_FIRST(&softc->user_ccb_queue)) != NULL) {
 541                 TAILQ_REMOVE(&softc->user_ccb_queue, ccb_h, periph_links.tqe);
 542                 targfreeccb(softc, (union ccb *)ccb_h);
 543         }
 544         while ((descr = TAILQ_FIRST(&softc->abort_queue)) != NULL) {
 545                 TAILQ_REMOVE(&softc->abort_queue, descr, tqe);
 546                 FREE(descr, M_TARG);
 547         }
 548
 549         softc->periph = NULL;
 550         softc->path = NULL;
 551         periph->softc = NULL;
 552 }
 553
 554 /* Receive CCBs from user mode proc and send them to the HBA */
 555 static int
 556 targwrite(struct dev_write_args *ap)
 557 {
 558         struct uio *uio = ap->a_uio;
 559         union ccb *user_ccb;
 560         struct targ_softc *softc;
 561         struct targ_cmd_descr *descr;
 562         int write_len, error;
 563         int func_code, priority;
 564
 565         softc = (struct targ_softc *)ap->a_head.a_dev->si_drv1;
 566         write_len = error = 0;
 567         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 568                   ("write - uio_resid %zu\n", uio->uio_resid));
 569         while (uio->uio_resid >= sizeof(user_ccb) && error == 0) {
 570                 union ccb *ccb;
 571
 572                 error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
 573                 if (error != 0) {
 574                         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 575                                   ("write - uiomove failed (%d)\n", error));
 576                         break;
 577                 }
 578                 priority = fuword(&user_ccb->ccb_h.pinfo.priority);
 579                 if (priority == -1) {
 580                         error = EINVAL;
 581                         break;
 582                 }
 583                 func_code = fuword(&user_ccb->ccb_h.func_code);
 584                 switch (func_code) {
 585                 case XPT_ACCEPT_TARGET_IO:
 586                 case XPT_IMMED_NOTIFY:
 587                         cam_periph_lock(softc->periph);
 588                         ccb = targgetccb(softc, func_code, priority);
 589                         descr = (struct targ_cmd_descr *)ccb->ccb_h.targ_descr;
 590                         descr->user_ccb = user_ccb;
 591                         descr->func_code = func_code;
 592                         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 593                                   ("Sent ATIO/INOT (%p)\n", user_ccb));
 594                         xpt_action(ccb);
 595                         TAILQ_INSERT_TAIL(&softc->pending_ccb_queue,
 596                                           &ccb->ccb_h,
 597                                           periph_links.tqe);
 598                         cam_periph_unlock(softc->periph);
 599                         break;
 600                 default:
 601                         cam_periph_lock(softc->periph);
 602                         if ((func_code & XPT_FC_QUEUED) != 0) {
 603                                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 604                                           ("Sending queued ccb %#x (%p)\n",
 605                                           func_code, user_ccb));
 606                                 descr = targgetdescr(softc);
 607                                 descr->user_ccb = user_ccb;
 608                                 descr->priority = priority;
 609                                 descr->func_code = func_code;
 610                                 crit_enter();
 611                                 TAILQ_INSERT_TAIL(&softc->work_queue,
 612                                                   descr, tqe);
 613                                 crit_exit();
 614                                 xpt_schedule(softc->periph, priority);
 615                         } else {
 616                                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 617                                           ("Sending inline ccb %#x (%p)\n",
 618                                           func_code, user_ccb));
 619                                 ccb = targgetccb(softc, func_code, priority);
 620                                 descr = (struct targ_cmd_descr *)
 621                                          ccb->ccb_h.targ_descr;
 622                                 descr->user_ccb = user_ccb;
 623                                 descr->priority = priority;
 624                                 descr->func_code = func_code;
 625                                 if (targusermerge(softc, descr, ccb) != EFAULT)
 626                                         targsendccb(softc, ccb, descr);
 627                                 targreturnccb(softc, ccb);
 628                         }
 629                         cam_periph_unlock(softc->periph);
 630                         break;
 631                 }
 632                 write_len += sizeof(user_ccb);
 633         }
 634
 635         /*
 636          * If we've successfully taken in some amount of
 637          * data, return success for that data first.  If
 638          * an error is persistent, it will be reported
 639          * on the next write.
 640          */
 641         if (error != 0 && write_len == 0)
 642                 return (error);
 643         if (write_len == 0 && uio->uio_resid != 0)
 644                 return (ENOSPC);
 645         return (0);
 646 }
 647
 648 /* Process requests (descrs) via the periph-supplied CCBs */
 649 static void
 650 targstart(struct cam_periph *periph, union ccb *start_ccb)
 651 {
 652         struct targ_softc *softc;
 653         struct targ_cmd_descr *descr, *next_descr;
 654         int error;
 655
 656         softc = (struct targ_softc *)periph->softc;
 657         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targstart %p\n", start_ccb));
 658
 659         crit_enter();
 660         descr = TAILQ_FIRST(&softc->work_queue);
 661         if (descr == NULL) {
 662                 crit_exit();
 663                 xpt_release_ccb(start_ccb);
 664         } else {
 665                 TAILQ_REMOVE(&softc->work_queue, descr, tqe);
 666                 next_descr = TAILQ_FIRST(&softc->work_queue);
 667                 crit_exit();
 668
 669                 /* Initiate a transaction using the descr and supplied CCB */
 670                 error = targusermerge(softc, descr, start_ccb);
 671                 if (error == 0)
 672                         error = targsendccb(softc, start_ccb, descr);
 673                 if (error != 0) {
 674                         xpt_print(periph->path,
 675                             "targsendccb failed, err %d\n", error);
 676                         xpt_release_ccb(start_ccb);
 677                         suword(&descr->user_ccb->ccb_h.status,
 678                                CAM_REQ_CMP_ERR);
 679                         crit_enter();
 680                         TAILQ_INSERT_TAIL(&softc->abort_queue, descr, tqe);
 681                         crit_exit();
 682                         notify_user(softc);
 683                 }
 684
 685                 /* If we have more work to do, stay scheduled */
 686                 if (next_descr != NULL)
 687                         xpt_schedule(periph, next_descr->priority);
 688         }
 689 }
 690
 691 static int
 692 targusermerge(struct targ_softc *softc, struct targ_cmd_descr *descr,
 693               union ccb *ccb)
 694 {
 695         struct ccb_hdr *u_ccbh, *k_ccbh;
 696         size_t ccb_len;
 697         int error;
 698
 699         u_ccbh = &descr->user_ccb->ccb_h;
 700         k_ccbh = &ccb->ccb_h;
 701
 702         /*
 703          * There are some fields in the CCB header that need to be
 704          * preserved, the rest we get from the user ccb. (See xpt_merge_ccb)
 705          */
 706         xpt_setup_ccb(k_ccbh, softc->path, descr->priority);
 707         k_ccbh->retry_count = fuword(&u_ccbh->retry_count);
 708         k_ccbh->func_code = descr->func_code;
 709         k_ccbh->flags = fuword(&u_ccbh->flags);
 710         k_ccbh->timeout = fuword(&u_ccbh->timeout);
 711         ccb_len = targccblen(k_ccbh->func_code) - sizeof(struct ccb_hdr);
 712         error = copyin(u_ccbh + 1, k_ccbh + 1, ccb_len);
 713         if (error != 0) {
 714                 k_ccbh->status = CAM_REQ_CMP_ERR;
 715                 return (error);
 716         }
 717
 718         /* Translate usermode abort_ccb pointer to its kernel counterpart */
 719         if (k_ccbh->func_code == XPT_ABORT) {
 720                 struct ccb_abort *cab;
 721                 struct ccb_hdr *ccb_h;
 722
 723                 cab = (struct ccb_abort *)ccb;
 724                 crit_enter();
 725                 TAILQ_FOREACH(ccb_h, &softc->pending_ccb_queue,
 726                     periph_links.tqe) {
 727                         struct targ_cmd_descr *ab_descr;
 728
 729                         ab_descr = (struct targ_cmd_descr *)ccb_h->targ_descr;
 730                         if (ab_descr->user_ccb == cab->abort_ccb) {
 731                                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 732                                           ("Changing abort for %p to %p\n",
 733                                           cab->abort_ccb, ccb_h));
 734                                 cab->abort_ccb = (union ccb *)ccb_h;
 735                                 break;
 736                         }
 737                 }
 738                 crit_exit();
 739                 /* CCB not found, set appropriate status */
 740                 if (ccb_h == NULL) {
 741                         k_ccbh->status = CAM_PATH_INVALID;
 742                         error = ESRCH;
 743                 }
 744         }
 745
 746         return (error);
 747 }
 748
 749 /* Build and send a kernel CCB formed from descr->user_ccb */
 750 static int
 751 targsendccb(struct targ_softc *softc, union ccb *ccb,
 752             struct targ_cmd_descr *descr)
 753 {
 754         struct cam_periph_map_info *mapinfo;
 755         struct ccb_hdr *ccb_h;
 756         int error;
 757
 758         ccb_h = &ccb->ccb_h;
 759         mapinfo = &descr->mapinfo;
 760         mapinfo->num_bufs_used = 0;
 761
 762         /*
 763          * There's no way for the user to have a completion
 764          * function, so we put our own completion function in here.
 765          * We also stash in a reference to our descriptor so targreturnccb()
 766          * can find our mapping info.
 767          */
 768         ccb_h->cbfcnp = targdone;
 769         ccb_h->targ_descr = descr;
 770
 771         /*
 772          * We only attempt to map the user memory into kernel space
 773          * if they haven't passed in a physical memory pointer,
 774          * and if there is actually an I/O operation to perform.
 775          * Right now cam_periph_mapmem() only supports SCSI and device
 776          * match CCBs.  For the SCSI CCBs, we only pass the CCB in if
 777          * there's actually data to map.  cam_periph_mapmem() will do the
 778          * right thing, even if there isn't data to map, but since CCBs
 779          * without data are a reasonably common occurance (e.g. test unit
 780          * ready), it will save a few cycles if we check for it here.
 781          */
 782         if (((ccb_h->flags & CAM_DATA_PHYS) == 0)
 783          && (((ccb_h->func_code == XPT_CONT_TARGET_IO)
 784             && ((ccb_h->flags & CAM_DIR_MASK) != CAM_DIR_NONE))
 785           || (ccb_h->func_code == XPT_DEV_MATCH))) {
 786
 787                 error = cam_periph_mapmem(ccb, mapinfo);
 788
 789                 /*
 790                  * cam_periph_mapmem returned an error, we can't continue.
 791                  * Return the error to the user.
 792                  */
 793                 if (error) {
 794                         ccb_h->status = CAM_REQ_CMP_ERR;
 795                         mapinfo->num_bufs_used = 0;
 796                         return (error);
 797                 }
 798         }
 799
 800         /*
 801          * Once queued on the pending CCB list, this CCB will be protected
 802          * by our error recovery handler.
 803          */
 804         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("sendccb %p\n", ccb));
 805         if (XPT_FC_IS_QUEUED(ccb)) {
 806                 crit_enter();
 807                 TAILQ_INSERT_TAIL(&softc->pending_ccb_queue, ccb_h,
 808                                   periph_links.tqe);
 809                 crit_exit();
 810         }
 811         xpt_action(ccb);
 812
 813         return (0);
 814 }
 815
 816 /* Completion routine for CCBs (called in a critical section) */
 817 static void
 818 targdone(struct cam_periph *periph, union ccb *done_ccb)
 819 {
 820         struct targ_softc *softc;
 821         cam_status status;
 822
 823         CAM_DEBUG(periph->path, CAM_DEBUG_PERIPH, ("targdone %p\n", done_ccb));
 824         softc = (struct targ_softc *)periph->softc;
 825         TAILQ_REMOVE(&softc->pending_ccb_queue, &done_ccb->ccb_h,
 826                      periph_links.tqe);
 827         status = done_ccb->ccb_h.status & CAM_STATUS_MASK;
 828
 829         /* If we're no longer enabled, throw away CCB */
 830         if ((softc->state & TARG_STATE_LUN_ENABLED) == 0) {
 831                 targfreeccb(softc, done_ccb);
 832                 return;
 833         }
 834         /* abort_all_pending() waits for pending queue to be empty */
 835         if (TAILQ_EMPTY(&softc->pending_ccb_queue))
 836                 wakeup(&softc->pending_ccb_queue);
 837
 838         switch (done_ccb->ccb_h.func_code) {
 839         /* All FC_*_QUEUED CCBs go back to userland */
 840         case XPT_IMMED_NOTIFY:
 841         case XPT_ACCEPT_TARGET_IO:
 842         case XPT_CONT_TARGET_IO:
 843                 TAILQ_INSERT_TAIL(&softc->user_ccb_queue, &done_ccb->ccb_h,
 844                                   periph_links.tqe);
 845                 notify_user(softc);
 846                 break;
 847         default:
 848                 panic("targdone: impossible xpt opcode %#x",
 849                       done_ccb->ccb_h.func_code);
 850                 /* NOTREACHED */
 851         }
 852 }
 853
 854 /* Return CCBs to the user from the user queue and abort queue */
 855 static int
 856 targread(struct dev_read_args *ap)
 857 {
 858         struct uio *uio = ap->a_uio;
 859         struct descr_queue      *abort_queue;
 860         struct targ_cmd_descr   *user_descr;
 861         struct targ_softc       *softc;
 862         struct ccb_queue  *user_queue;
 863         struct ccb_hdr    *ccb_h;
 864         union  ccb        *user_ccb;
 865         int                read_len, error;
 866
 867         error = 0;
 868         read_len = 0;
 869         softc = (struct targ_softc *)ap->a_head.a_dev->si_drv1;
 870         user_queue = &softc->user_ccb_queue;
 871         abort_queue = &softc->abort_queue;
 872         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targread\n"));
 873
 874         /* If no data is available, wait or return immediately */
 875         cam_periph_lock(softc->periph);
 876         ccb_h = TAILQ_FIRST(user_queue);
 877         user_descr = TAILQ_FIRST(abort_queue);
 878         while (ccb_h == NULL && user_descr == NULL) {
 879                 if ((ap->a_ioflag & IO_NDELAY) == 0) {
 880                         error = sim_lock_sleep(user_queue, PCATCH, "targrd", 0,
 881                                                softc->periph->sim->lock);
 882                         ccb_h = TAILQ_FIRST(user_queue);
 883                         user_descr = TAILQ_FIRST(abort_queue);
 884                         if (error != 0) {
 885                                 if (error == ERESTART) {
 886                                         continue;
 887                                 } else {
 888                                         goto read_fail;
 889                                 }
 890                         }
 891                 } else {
 892                         cam_periph_unlock(softc->periph);
 893                         return (EAGAIN);
 894                 }
 895         }
 896
 897         /* Data is available so fill the user's buffer */
 898         while (ccb_h != NULL) {
 899                 struct targ_cmd_descr *descr;
 900
 901                 if (uio->uio_resid < sizeof(user_ccb))
 902                         break;
 903                 TAILQ_REMOVE(user_queue, ccb_h, periph_links.tqe);
 904                 descr = (struct targ_cmd_descr *)ccb_h->targ_descr;
 905                 user_ccb = descr->user_ccb;
 906                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 907                           ("targread ccb %p (%p)\n", ccb_h, user_ccb));
 908                 error = targreturnccb(softc, (union ccb *)ccb_h);
 909                 if (error != 0)
 910                         goto read_fail;
 911                 cam_periph_unlock(softc->periph);
 912                 error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
 913                 cam_periph_lock(softc->periph);
 914                 if (error != 0)
 915                         goto read_fail;
 916                 read_len += sizeof(user_ccb);
 917
 918                 ccb_h = TAILQ_FIRST(user_queue);
 919         }
 920
 921         /* Flush out any aborted descriptors */
 922         while (user_descr != NULL) {
 923                 if (uio->uio_resid < sizeof(user_ccb))
 924                         break;
 925                 TAILQ_REMOVE(abort_queue, user_descr, tqe);
 926                 user_ccb = user_descr->user_ccb;
 927                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 928                           ("targread aborted descr %p (%p)\n",
 929                           user_descr, user_ccb));
 930                 suword(&user_ccb->ccb_h.status, CAM_REQ_ABORTED);
 931                 cam_periph_unlock(softc->periph);
 932                 error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
 933                 cam_periph_lock(softc->periph);
 934                 if (error != 0)
 935                         goto read_fail;
 936                 read_len += sizeof(user_ccb);
 937
 938                 user_descr = TAILQ_FIRST(abort_queue);
 939         }
 940
 941         /*
 942          * If we've successfully read some amount of data, don't report an
 943          * error.  If the error is persistent, it will be reported on the
 944          * next read().
 945          */
 946         if (read_len == 0 && uio->uio_resid != 0)
 947                 error = ENOSPC;
 948
 949 read_fail:
 950         cam_periph_unlock(softc->periph);
 951         return (error);
 952 }
 953
 954 /* Copy completed ccb back to the user */
 955 static int
 956 targreturnccb(struct targ_softc *softc, union ccb *ccb)
 957 {
 958         struct targ_cmd_descr *descr;
 959         struct ccb_hdr *u_ccbh;
 960         size_t ccb_len;
 961         int error;
 962
 963         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targreturnccb %p\n", ccb));
 964         descr = (struct targ_cmd_descr *)ccb->ccb_h.targ_descr;
 965         u_ccbh = &descr->user_ccb->ccb_h;
 966
 967         /* Copy out the central portion of the ccb_hdr */
 968         copyout(&ccb->ccb_h.retry_count, &u_ccbh->retry_count,
 969                 offsetof(struct ccb_hdr, periph_priv) -
 970                 offsetof(struct ccb_hdr, retry_count));
 971
 972         /* Copy out the rest of the ccb (after the ccb_hdr) */
 973         ccb_len = targccblen(ccb->ccb_h.func_code) - sizeof(struct ccb_hdr);
 974         if (descr->mapinfo.num_bufs_used != 0)
 975                 cam_periph_unmapmem(ccb, &descr->mapinfo);
 976         error = copyout(&ccb->ccb_h + 1, u_ccbh + 1, ccb_len);
 977         if (error != 0) {
 978                 xpt_print(softc->path,
 979                     "targreturnccb - CCB copyout failed (%d)\n", error);
 980         }
 981         /* Free CCB or send back to devq. */
 982         targfreeccb(softc, ccb);
 983
 984         return (error);
 985 }
 986
 987 static union ccb *
 988 targgetccb(struct targ_softc *softc, xpt_opcode type, int priority)
 989 {
 990         union ccb *ccb;
 991         int ccb_len;
 992
 993         ccb_len = targccblen(type);
 994         MALLOC(ccb, union ccb *, ccb_len, M_TARG, M_INTWAIT);
 995         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("getccb %p\n", ccb));
 996
 997         xpt_setup_ccb(&ccb->ccb_h, softc->path, priority);
 998         ccb->ccb_h.func_code = type;
 999         ccb->ccb_h.cbfcnp = targdone;
1000         ccb->ccb_h.targ_descr = targgetdescr(softc);
1001         return (ccb);
1002 }
1003
1004 static void
1005 targfreeccb(struct targ_softc *softc, union ccb *ccb)
1006 {
1007         CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH, ("targfreeccb descr %p and\n",
1008                         ccb->ccb_h.targ_descr));
1009         FREE(ccb->ccb_h.targ_descr, M_TARG);
1010
1011         switch (ccb->ccb_h.func_code) {
1012         case XPT_ACCEPT_TARGET_IO:
1013         case XPT_IMMED_NOTIFY:
1014                 CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH, ("freeing ccb %p\n", ccb));
1015                 FREE(ccb, M_TARG);
1016                 break;
1017         default:
1018                 /* Send back CCB if we got it from the periph */
1019                 if (XPT_FC_IS_QUEUED(ccb)) {
1020                         CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH,
1021                                         ("returning queued ccb %p\n", ccb));
1022                         xpt_release_ccb(ccb);
1023                 } else {
1024                         CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH,
1025                                         ("freeing ccb %p\n", ccb));
1026                         FREE(ccb, M_TARG);
1027                 }
1028                 break;
1029         }
1030 }
1031
1032 static struct targ_cmd_descr *
1033 targgetdescr(struct targ_softc *softc)
1034 {
1035         struct targ_cmd_descr *descr;
1036
1037         MALLOC(descr, struct targ_cmd_descr *, sizeof(*descr),
1038                 M_TARG, M_INTWAIT);
1039         descr->mapinfo.num_bufs_used = 0;
1040         return (descr);
1041 }
1042
1043 static int
1044 targclone(struct dev_clone_args *ap)
1045 {
1046         int unit;
1047
1048         unit = devfs_clone_bitmap_get(&DEVFS_CLONE_BITMAP(targ), 0);
1049         ap->a_dev = make_only_dev(&targ_ops, unit, UID_ROOT, GID_WHEEL,
1050                                   0600, "targ%d", unit);
1051         return 0;
1052 }
1053
1054 static void
1055 targinit(void)
1056 {
1057         make_autoclone_dev(&targ_ops, &DEVFS_CLONE_BITMAP(targ),
1058                 targclone, UID_ROOT, GID_WHEEL, 0600, "targ");
1059         /* XXX: need uninit or so? */
1060 }
1061
1062 static void
1063 targasync(void *callback_arg, u_int32_t code, struct cam_path *path, void *arg)
1064 {
1065         /* All events are handled in usermode by INOTs */
1066         panic("targasync() called, should be an INOT instead");
1067 }
1068
1069 /* Cancel all pending requests and CCBs awaiting work. */
1070 static void
1071 abort_all_pending(struct targ_softc *softc)
1072 {
1073         struct targ_cmd_descr   *descr;
1074         struct ccb_abort         cab;
1075         struct ccb_hdr          *ccb_h;
1076         struct cam_sim          *sim;
1077
1078         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("abort_all_pending\n"));
1079
1080         /* First abort the descriptors awaiting resources */
1081         while ((descr = TAILQ_FIRST(&softc->work_queue)) != NULL) {
1082                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
1083                           ("Aborting descr from workq %p\n", descr));
1084                 TAILQ_REMOVE(&softc->work_queue, descr, tqe);
1085                 TAILQ_INSERT_TAIL(&softc->abort_queue, descr, tqe);
1086         }
1087
1088         /*
1089          * Then abort all pending CCBs.
1090          * targdone() will return the aborted CCB via user_ccb_queue
1091          */
1092         xpt_setup_ccb(&cab.ccb_h, softc->path, /*priority*/0);
1093         cab.ccb_h.func_code = XPT_ABORT;
1094         cab.ccb_h.status = CAM_REQ_CMP_ERR;
1095         TAILQ_FOREACH(ccb_h, &softc->pending_ccb_queue, periph_links.tqe) {
1096                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
1097                           ("Aborting pending CCB %p\n", ccb_h));
1098                 cab.abort_ccb = (union ccb *)ccb_h;
1099                 xpt_action((union ccb *)&cab);
1100                 if (cab.ccb_h.status != CAM_REQ_CMP) {
1101                         xpt_print(cab.ccb_h.path,
1102                             "Unable to abort CCB, status %#x\n",
1103                             cab.ccb_h.status);
1104                 }
1105         }
1106
1107         /* If we aborted at least one pending CCB ok, wait for it. */
1108         if (cab.ccb_h.status == CAM_REQ_CMP) {
1109                 sim = xpt_path_sim(softc->path);
1110                 sim_lock_sleep(&softc->pending_ccb_queue, PCATCH, "tgabrt", 0,
1111                                sim->lock);
1112         }
1113
1114         /* If we aborted anything from the work queue, wakeup user. */
1115         if (!TAILQ_EMPTY(&softc->user_ccb_queue)
1116          || !TAILQ_EMPTY(&softc->abort_queue))
1117                 notify_user(softc);
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         selwakeup(&softc->read_select);
1129         KNOTE(&softc->read_select.si_note, 0);
1130         wakeup(&softc->user_ccb_queue);
1131 }
1132
1133 /* Convert CAM status to errno values */
1134 static int
1135 targcamstatus(cam_status status)
1136 {
1137         switch (status & CAM_STATUS_MASK) {
1138         case CAM_REQ_CMP:       /* CCB request completed without error */
1139                 return (0);
1140         case CAM_REQ_INPROG:    /* CCB request is in progress */
1141                 return (EINPROGRESS);
1142         case CAM_REQ_CMP_ERR:   /* CCB request completed with an error */
1143                 return (EIO);
1144         case CAM_PROVIDE_FAIL:  /* Unable to provide requested capability */
1145                 return (ENOTTY);
1146         case CAM_FUNC_NOTAVAIL: /* The requested function is not available */
1147                 return (ENOTSUP);
1148         case CAM_LUN_ALRDY_ENA: /* LUN is already enabled for target mode */
1149                 return (EADDRINUSE);
1150         case CAM_PATH_INVALID:  /* Supplied Path ID is invalid */
1151         case CAM_DEV_NOT_THERE: /* SCSI Device Not Installed/there */
1152                 return (ENOENT);
1153         case CAM_REQ_ABORTED:   /* CCB request aborted by the host */
1154                 return (ECANCELED);
1155         case CAM_CMD_TIMEOUT:   /* Command timeout */
1156                 return (ETIMEDOUT);
1157         case CAM_REQUEUE_REQ:   /* Requeue to preserve transaction ordering */
1158                 return (EAGAIN);
1159         case CAM_REQ_INVALID:   /* CCB request was invalid */
1160                 return (EINVAL);
1161         case CAM_RESRC_UNAVAIL: /* Resource Unavailable */
1162                 return (ENOMEM);
1163         case CAM_BUSY:          /* CAM subsytem is busy */
1164         case CAM_UA_ABORT:      /* Unable to abort CCB request */
1165                 return (EBUSY);
1166         default:
1167                 return (ENXIO);
1168         }
1169 }
1170
1171 static size_t
1172 targccblen(xpt_opcode func_code)
1173 {
1174         int len;
1175
1176         /* Codes we expect to see as a target */
1177         switch (func_code) {
1178         case XPT_CONT_TARGET_IO:
1179         case XPT_SCSI_IO:
1180                 len = sizeof(struct ccb_scsiio);
1181                 break;
1182         case XPT_ACCEPT_TARGET_IO:
1183                 len = sizeof(struct ccb_accept_tio);
1184                 break;
1185         case XPT_IMMED_NOTIFY:
1186                 len = sizeof(struct ccb_immed_notify);
1187                 break;
1188         case XPT_REL_SIMQ:
1189                 len = sizeof(struct ccb_relsim);
1190                 break;
1191         case XPT_PATH_INQ:
1192                 len = sizeof(struct ccb_pathinq);
1193                 break;
1194         case XPT_DEBUG:
1195                 len = sizeof(struct ccb_debug);
1196                 break;
1197         case XPT_ABORT:
1198                 len = sizeof(struct ccb_abort);
1199                 break;
1200         case XPT_EN_LUN:
1201                 len = sizeof(struct ccb_en_lun);
1202                 break;
1203         default:
1204                 len = sizeof(union ccb);
1205                 break;
1206         }
1207
1208         return (len);
1209 }