sys/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
  30 #include <sys/cdefs.h>
  31 __FBSDID("$FreeBSD$");
  32
  33
  34 #include <sys/param.h>
  35 #include <sys/systm.h>
  36 #include <sys/kernel.h>
  37 #include <sys/conf.h>
  38 #include <sys/malloc.h>
  39 #include <sys/poll.h>
  40 #include <sys/vnode.h>
  41 #include <sys/lock.h>
  42 #include <sys/mutex.h>
  43 #include <sys/devicestat.h>
  44 #include <sys/proc.h>
  45 /* Includes to support callout */
  46 #include <sys/types.h>
  47 #include <sys/systm.h>
  48
  49 #include <cam/cam.h>
  50 #include <cam/cam_ccb.h>
  51 #include <cam/cam_periph.h>
  52 #include <cam/cam_xpt_periph.h>
  53 #include <cam/cam_sim.h>
  54 #include <cam/scsi/scsi_targetio.h>
  55
  56
  57 /* Transaction information attached to each CCB sent by the user */
  58 struct targ_cmd_descr {
  59         struct cam_periph_map_info  mapinfo;
  60         TAILQ_ENTRY(targ_cmd_descr) tqe;
  61         union ccb *user_ccb;
  62         int        priority;
  63         int        func_code;
  64 };
  65
  66 /* Offset into the private CCB area for storing our descriptor */
  67 #define targ_descr      periph_priv.entries[1].ptr
  68
  69 TAILQ_HEAD(descr_queue, targ_cmd_descr);
  70
  71 typedef enum {
  72         TARG_STATE_RESV         = 0x00, /* Invalid state */
  73         TARG_STATE_OPENED       = 0x01, /* Device opened, softc initialized */
  74         TARG_STATE_LUN_ENABLED  = 0x02  /* Device enabled for a path */
  75 } targ_state;
  76
  77 /* Per-instance device software context */
  78 struct targ_softc {
  79         /* CCBs (CTIOs, ATIOs, INOTs) pending on the controller */
  80         struct ccb_queue         pending_ccb_queue;
  81
  82         /* Command descriptors awaiting CTIO resources from the XPT */
  83         struct descr_queue       work_queue;
  84
  85         /* Command descriptors that have been aborted back to the user. */
  86         struct descr_queue       abort_queue;
  87
  88         /*
  89          * Queue of CCBs that have been copied out to userland, but our
  90          * userland daemon has not yet seen.
  91          */
  92         struct ccb_queue         user_ccb_queue;
  93
  94         struct cam_periph       *periph;
  95         struct cam_path         *path;
  96         targ_state               state;
  97         struct selinfo           read_select;
  98         struct devstat           device_stats;
  99 };
 100
 101 static d_open_t         targopen;
 102 static d_read_t         targread;
 103 static d_write_t        targwrite;
 104 static d_ioctl_t        targioctl;
 105 static d_poll_t         targpoll;
 106 static d_kqfilter_t     targkqfilter;
 107 static void             targreadfiltdetach(struct knote *kn);
 108 static int              targreadfilt(struct knote *kn, long hint);
 109 static struct filterops targread_filtops = {
 110         .f_isfd = 1,
 111         .f_detach = targreadfiltdetach,
 112         .f_event = targreadfilt,
 113 };
 114
 115 static struct cdevsw targ_cdevsw = {
 116         .d_version =    D_VERSION,
 117         .d_flags =      D_NEEDGIANT,
 118         .d_open =       targopen,
 119         .d_read =       targread,
 120         .d_write =      targwrite,
 121         .d_ioctl =      targioctl,
 122         .d_poll =       targpoll,
 123         .d_name =       "targ",
 124         .d_kqfilter =   targkqfilter
 125 };
 126
 127 static cam_status       targendislun(struct cam_path *path, int enable,
 128                                      int grp6_len, int grp7_len);
 129 static cam_status       targenable(struct targ_softc *softc,
 130                                    struct cam_path *path,
 131                                    int grp6_len, int grp7_len);
 132 static cam_status       targdisable(struct targ_softc *softc);
 133 static periph_ctor_t    targctor;
 134 static periph_dtor_t    targdtor;
 135 static periph_start_t   targstart;
 136 static int              targusermerge(struct targ_softc *softc,
 137                                       struct targ_cmd_descr *descr,
 138                                       union ccb *ccb);
 139 static int              targsendccb(struct targ_softc *softc, union ccb *ccb,
 140                                     struct targ_cmd_descr *descr);
 141 static void             targdone(struct cam_periph *periph,
 142                                  union  ccb *done_ccb);
 143 static int              targreturnccb(struct targ_softc *softc,
 144                                       union  ccb *ccb);
 145 static union ccb *      targgetccb(struct targ_softc *softc, xpt_opcode type,
 146                                    int priority);
 147 static void             targfreeccb(struct targ_softc *softc, union ccb *ccb);
 148 static struct targ_cmd_descr *
 149                         targgetdescr(struct targ_softc *softc);
 150 static periph_init_t    targinit;
 151 static void             targasync(void *callback_arg, u_int32_t code,
 152                                   struct cam_path *path, void *arg);
 153 static void             abort_all_pending(struct targ_softc *softc);
 154 static void             notify_user(struct targ_softc *softc);
 155 static int              targcamstatus(cam_status status);
 156 static size_t           targccblen(xpt_opcode func_code);
 157
 158 static struct periph_driver targdriver =
 159 {
 160         targinit, "targ",
 161         TAILQ_HEAD_INITIALIZER(targdriver.units), /* generation */ 0
 162 };
 163 PERIPHDRIVER_DECLARE(targ, targdriver);
 164
 165 static MALLOC_DEFINE(M_TARG, "TARG", "TARG data");
 166
 167 /* Disable LUN if enabled and teardown softc */
 168 static void
 169 targcdevdtor(void *data)
 170 {
 171         struct targ_softc *softc;
 172         struct cam_periph *periph;
 173
 174         softc = data;
 175         if (softc->periph == NULL) {
 176                 printf("%s: destroying non-enabled target\n", __func__);
 177                 free(softc, M_TARG);
 178                 return;
 179         }
 180
 181         /*
 182          * Acquire a hold on the periph so that it doesn't go away before
 183          * we are ready at the end of the function.
 184          */
 185         periph = softc->periph;
 186         cam_periph_acquire(periph);
 187         cam_periph_lock(periph);
 188         (void)targdisable(softc);
 189         if (softc->periph != NULL) {
 190                 cam_periph_invalidate(softc->periph);
 191                 softc->periph = NULL;
 192         }
 193         cam_periph_unlock(periph);
 194         cam_periph_release(periph);
 195         free(softc, M_TARG);
 196 }
 197
 198 /*
 199  * Create softc and initialize it.  There is no locking here because a
 200  * periph doesn't get created until an ioctl is issued to do so, and
 201  * that can't happen until this method returns.
 202  */
 203 static int
 204 targopen(struct cdev *dev, int flags, int fmt, struct thread *td)
 205 {
 206         struct targ_softc *softc;
 207
 208         /* Allocate its softc, initialize it */
 209         softc = malloc(sizeof(*softc), M_TARG,
 210                M_WAITOK | M_ZERO);
 211         softc->state = TARG_STATE_OPENED;
 212         softc->periph = NULL;
 213         softc->path = NULL;
 214
 215         TAILQ_INIT(&softc->pending_ccb_queue);
 216         TAILQ_INIT(&softc->work_queue);
 217         TAILQ_INIT(&softc->abort_queue);
 218         TAILQ_INIT(&softc->user_ccb_queue);
 219         knlist_init_mtx(&softc->read_select.si_note, NULL);
 220
 221         devfs_set_cdevpriv(softc, targcdevdtor);
 222         return (0);
 223 }
 224
 225 /* Enable/disable LUNs, set debugging level */
 226 static int
 227 targioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flag, struct thread *td)
 228 {
 229         struct targ_softc *softc;
 230         cam_status         status;
 231
 232         devfs_get_cdevpriv((void **)&softc);
 233
 234         switch (cmd) {
 235         case TARGIOCENABLE:
 236         {
 237                 struct ioc_enable_lun   *new_lun;
 238                 struct cam_path         *path;
 239
 240                 new_lun = (struct ioc_enable_lun *)addr;
 241                 status = xpt_create_path(&path, /*periph*/NULL,
 242                                           new_lun->path_id,
 243                                           new_lun->target_id,
 244                                           new_lun->lun_id);
 245                 if (status != CAM_REQ_CMP) {
 246                         printf("Couldn't create path, status %#x\n", status);
 247                         break;
 248                 }
 249                 xpt_path_lock(path);
 250                 status = targenable(softc, path, new_lun->grp6_len,
 251                                     new_lun->grp7_len);
 252                 xpt_path_unlock(path);
 253                 xpt_free_path(path);
 254                 break;
 255         }
 256         case TARGIOCDISABLE:
 257                 if (softc->periph == NULL) {
 258                         status = CAM_DEV_NOT_THERE;
 259                         break;
 260                 }
 261                 cam_periph_lock(softc->periph);
 262                 status = targdisable(softc);
 263                 cam_periph_unlock(softc->periph);
 264                 break;
 265         case TARGIOCDEBUG:
 266         {
 267                 struct ccb_debug cdbg;
 268
 269                 /* If no periph available, disallow debugging changes */
 270                 if ((softc->state & TARG_STATE_LUN_ENABLED) == 0) {
 271                         status = CAM_DEV_NOT_THERE;
 272                         break;
 273                 }
 274                 bzero(&cdbg, sizeof cdbg);
 275                 if (*((int *)addr) != 0)
 276                         cdbg.flags = CAM_DEBUG_PERIPH;
 277                 else
 278                         cdbg.flags = CAM_DEBUG_NONE;
 279                 xpt_setup_ccb(&cdbg.ccb_h, softc->path, CAM_PRIORITY_NORMAL);
 280                 cdbg.ccb_h.func_code = XPT_DEBUG;
 281                 cdbg.ccb_h.cbfcnp = targdone;
 282                 xpt_action((union ccb *)&cdbg);
 283                 status = cdbg.ccb_h.status & CAM_STATUS_MASK;
 284                 break;
 285         }
 286         default:
 287                 status = CAM_PROVIDE_FAIL;
 288                 break;
 289         }
 290
 291         return (targcamstatus(status));
 292 }
 293
 294 /* Writes are always ready, reads wait for user_ccb_queue or abort_queue */
 295 static int
 296 targpoll(struct cdev *dev, int poll_events, struct thread *td)
 297 {
 298         struct targ_softc *softc;
 299         int     revents;
 300
 301         devfs_get_cdevpriv((void **)&softc);
 302
 303         /* Poll for write() is always ok. */
 304         revents = poll_events & (POLLOUT | POLLWRNORM);
 305         if ((poll_events & (POLLIN | POLLRDNORM)) != 0) {
 306                 /* Poll for read() depends on user and abort queues. */
 307                 cam_periph_lock(softc->periph);
 308                 if (!TAILQ_EMPTY(&softc->user_ccb_queue) ||
 309                     !TAILQ_EMPTY(&softc->abort_queue)) {
 310                         revents |= poll_events & (POLLIN | POLLRDNORM);
 311                 }
 312                 cam_periph_unlock(softc->periph);
 313                 /* Only sleep if the user didn't poll for write. */
 314                 if (revents == 0)
 315                         selrecord(td, &softc->read_select);
 316         }
 317
 318         return (revents);
 319 }
 320
 321 static int
 322 targkqfilter(struct cdev *dev, struct knote *kn)
 323 {
 324         struct  targ_softc *softc;
 325
 326         devfs_get_cdevpriv((void **)&softc);
 327         kn->kn_hook = (caddr_t)softc;
 328         kn->kn_fop = &targread_filtops;
 329         knlist_add(&softc->read_select.si_note, kn, 0);
 330         return (0);
 331 }
 332
 333 static void
 334 targreadfiltdetach(struct knote *kn)
 335 {
 336         struct  targ_softc *softc;
 337
 338         softc = (struct targ_softc *)kn->kn_hook;
 339         knlist_remove(&softc->read_select.si_note, kn, 0);
 340 }
 341
 342 /* Notify the user's kqueue when the user queue or abort queue gets a CCB */
 343 static int
 344 targreadfilt(struct knote *kn, long hint)
 345 {
 346         struct targ_softc *softc;
 347         int     retval;
 348
 349         softc = (struct targ_softc *)kn->kn_hook;
 350         cam_periph_lock(softc->periph);
 351         retval = !TAILQ_EMPTY(&softc->user_ccb_queue) ||
 352                  !TAILQ_EMPTY(&softc->abort_queue);
 353         cam_periph_unlock(softc->periph);
 354         return (retval);
 355 }
 356
 357 /* Send the HBA the enable/disable message */
 358 static cam_status
 359 targendislun(struct cam_path *path, int enable, int grp6_len, int grp7_len)
 360 {
 361         struct ccb_en_lun en_ccb;
 362         cam_status        status;
 363
 364         /* Tell the lun to begin answering selects */
 365         xpt_setup_ccb(&en_ccb.ccb_h, path, CAM_PRIORITY_NORMAL);
 366         en_ccb.ccb_h.func_code = XPT_EN_LUN;
 367         /* Don't need support for any vendor specific commands */
 368         en_ccb.grp6_len = grp6_len;
 369         en_ccb.grp7_len = grp7_len;
 370         en_ccb.enable = enable ? 1 : 0;
 371         xpt_action((union ccb *)&en_ccb);
 372         status = en_ccb.ccb_h.status & CAM_STATUS_MASK;
 373         if (status != CAM_REQ_CMP) {
 374                 xpt_print(path, "%sable lun CCB rejected, status %#x\n",
 375                     enable ? "en" : "dis", status);
 376         }
 377         return (status);
 378 }
 379
 380 /* Enable target mode on a LUN, given its path */
 381 static cam_status
 382 targenable(struct targ_softc *softc, struct cam_path *path, int grp6_len,
 383            int grp7_len)
 384 {
 385         struct cam_periph *periph;
 386         struct ccb_pathinq cpi;
 387         cam_status         status;
 388
 389         if ((softc->state & TARG_STATE_LUN_ENABLED) != 0)
 390                 return (CAM_LUN_ALRDY_ENA);
 391
 392         /* Make sure SIM supports target mode */
 393         xpt_setup_ccb(&cpi.ccb_h, path, CAM_PRIORITY_NORMAL);
 394         cpi.ccb_h.func_code = XPT_PATH_INQ;
 395         xpt_action((union ccb *)&cpi);
 396         status = cpi.ccb_h.status & CAM_STATUS_MASK;
 397         if (status != CAM_REQ_CMP) {
 398                 printf("pathinq failed, status %#x\n", status);
 399                 goto enable_fail;
 400         }
 401         if ((cpi.target_sprt & PIT_PROCESSOR) == 0) {
 402                 printf("controller does not support target mode\n");
 403                 status = CAM_FUNC_NOTAVAIL;
 404                 goto enable_fail;
 405         }
 406
 407         /* Destroy any periph on our path if it is disabled */
 408         periph = cam_periph_find(path, "targ");
 409         if (periph != NULL) {
 410                 struct targ_softc *del_softc;
 411
 412                 del_softc = (struct targ_softc *)periph->softc;
 413                 if ((del_softc->state & TARG_STATE_LUN_ENABLED) == 0) {
 414                         cam_periph_invalidate(del_softc->periph);
 415                         del_softc->periph = NULL;
 416                 } else {
 417                         printf("Requested path still in use by targ%d\n",
 418                                periph->unit_number);
 419                         status = CAM_LUN_ALRDY_ENA;
 420                         goto enable_fail;
 421                 }
 422         }
 423
 424         /* Create a periph instance attached to this path */
 425         status = cam_periph_alloc(targctor, NULL, targdtor, targstart,
 426                         "targ", CAM_PERIPH_BIO, path, targasync, 0, softc);
 427         if (status != CAM_REQ_CMP) {
 428                 printf("cam_periph_alloc failed, status %#x\n", status);
 429                 goto enable_fail;
 430         }
 431
 432         /* Ensure that the periph now exists. */
 433         if (cam_periph_find(path, "targ") == NULL) {
 434                 panic("targenable: succeeded but no periph?");
 435                 /* NOTREACHED */
 436         }
 437
 438         /* Send the enable lun message */
 439         status = targendislun(path, /*enable*/1, grp6_len, grp7_len);
 440         if (status != CAM_REQ_CMP) {
 441                 printf("enable lun failed, status %#x\n", status);
 442                 goto enable_fail;
 443         }
 444         softc->state |= TARG_STATE_LUN_ENABLED;
 445
 446 enable_fail:
 447         return (status);
 448 }
 449
 450 /* Disable this softc's target instance if enabled */
 451 static cam_status
 452 targdisable(struct targ_softc *softc)
 453 {
 454         cam_status status;
 455
 456         if ((softc->state & TARG_STATE_LUN_ENABLED) == 0)
 457                 return (CAM_REQ_CMP);
 458
 459         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targdisable\n"));
 460
 461         /* Abort any ccbs pending on the controller */
 462         abort_all_pending(softc);
 463
 464         /* Disable this lun */
 465         status = targendislun(softc->path, /*enable*/0,
 466                               /*grp6_len*/0, /*grp7_len*/0);
 467         if (status == CAM_REQ_CMP)
 468                 softc->state &= ~TARG_STATE_LUN_ENABLED;
 469         else
 470                 printf("Disable lun failed, status %#x\n", status);
 471
 472         return (status);
 473 }
 474
 475 /* Initialize a periph (called from cam_periph_alloc) */
 476 static cam_status
 477 targctor(struct cam_periph *periph, void *arg)
 478 {
 479         struct targ_softc *softc;
 480
 481         /* Store pointer to softc for periph-driven routines */
 482         softc = (struct targ_softc *)arg;
 483         periph->softc = softc;
 484         softc->periph = periph;
 485         softc->path = periph->path;
 486         return (CAM_REQ_CMP);
 487 }
 488
 489 static void
 490 targdtor(struct cam_periph *periph)
 491 {
 492         struct targ_softc     *softc;
 493         struct ccb_hdr        *ccb_h;
 494         struct targ_cmd_descr *descr;
 495
 496         softc = (struct targ_softc *)periph->softc;
 497
 498         /*
 499          * targdisable() aborts CCBs back to the user and leaves them
 500          * on user_ccb_queue and abort_queue in case the user is still
 501          * interested in them.  We free them now.
 502          */
 503         while ((ccb_h = TAILQ_FIRST(&softc->user_ccb_queue)) != NULL) {
 504                 TAILQ_REMOVE(&softc->user_ccb_queue, ccb_h, periph_links.tqe);
 505                 targfreeccb(softc, (union ccb *)ccb_h);
 506         }
 507         while ((descr = TAILQ_FIRST(&softc->abort_queue)) != NULL) {
 508                 TAILQ_REMOVE(&softc->abort_queue, descr, tqe);
 509                 free(descr, M_TARG);
 510         }
 511
 512         softc->periph = NULL;
 513         softc->path = NULL;
 514         periph->softc = NULL;
 515 }
 516
 517 /* Receive CCBs from user mode proc and send them to the HBA */
 518 static int
 519 targwrite(struct cdev *dev, struct uio *uio, int ioflag)
 520 {
 521         union ccb *user_ccb;
 522         struct targ_softc *softc;
 523         struct targ_cmd_descr *descr;
 524         int write_len, error;
 525         int func_code, priority;
 526
 527         devfs_get_cdevpriv((void **)&softc);
 528         write_len = error = 0;
 529         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 530                   ("write - uio_resid %zd\n", uio->uio_resid));
 531         while (uio->uio_resid >= sizeof(user_ccb) && error == 0) {
 532                 union ccb *ccb;
 533
 534                 error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
 535                 if (error != 0) {
 536                         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 537                                   ("write - uiomove failed (%d)\n", error));
 538                         break;
 539                 }
 540                 priority = fuword32(&user_ccb->ccb_h.pinfo.priority);
 541                 if (priority == CAM_PRIORITY_NONE) {
 542                         error = EINVAL;
 543                         break;
 544                 }
 545                 func_code = fuword32(&user_ccb->ccb_h.func_code);
 546                 switch (func_code) {
 547                 case XPT_ACCEPT_TARGET_IO:
 548                 case XPT_IMMED_NOTIFY:
 549                 case XPT_IMMEDIATE_NOTIFY:
 550                         cam_periph_lock(softc->periph);
 551                         ccb = targgetccb(softc, func_code, priority);
 552                         descr = (struct targ_cmd_descr *)ccb->ccb_h.targ_descr;
 553                         descr->user_ccb = user_ccb;
 554                         descr->func_code = func_code;
 555                         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 556                                   ("Sent ATIO/INOT (%p)\n", user_ccb));
 557                         xpt_action(ccb);
 558                         TAILQ_INSERT_TAIL(&softc->pending_ccb_queue,
 559                                           &ccb->ccb_h,
 560                                           periph_links.tqe);
 561                         cam_periph_unlock(softc->periph);
 562                         break;
 563                 default:
 564                         cam_periph_lock(softc->periph);
 565                         if ((func_code & XPT_FC_QUEUED) != 0) {
 566                                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 567                                           ("Sending queued ccb %#x (%p)\n",
 568                                           func_code, user_ccb));
 569                                 descr = targgetdescr(softc);
 570                                 descr->user_ccb = user_ccb;
 571                                 descr->priority = priority;
 572                                 descr->func_code = func_code;
 573                                 TAILQ_INSERT_TAIL(&softc->work_queue,
 574                                                   descr, tqe);
 575                                 xpt_schedule(softc->periph, priority);
 576                         } else {
 577                                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 578                                           ("Sending inline ccb %#x (%p)\n",
 579                                           func_code, user_ccb));
 580                                 ccb = targgetccb(softc, func_code, priority);
 581                                 descr = (struct targ_cmd_descr *)
 582                                          ccb->ccb_h.targ_descr;
 583                                 descr->user_ccb = user_ccb;
 584                                 descr->priority = priority;
 585                                 descr->func_code = func_code;
 586                                 if (targusermerge(softc, descr, ccb) != EFAULT)
 587                                         targsendccb(softc, ccb, descr);
 588                                 targreturnccb(softc, ccb);
 589                         }
 590                         cam_periph_unlock(softc->periph);
 591                         break;
 592                 }
 593                 write_len += sizeof(user_ccb);
 594         }
 595
 596         /*
 597          * If we've successfully taken in some amount of
 598          * data, return success for that data first.  If
 599          * an error is persistent, it will be reported
 600          * on the next write.
 601          */
 602         if (error != 0 && write_len == 0)
 603                 return (error);
 604         if (write_len == 0 && uio->uio_resid != 0)
 605                 return (ENOSPC);
 606         return (0);
 607 }
 608
 609 /* Process requests (descrs) via the periph-supplied CCBs */
 610 static void
 611 targstart(struct cam_periph *periph, union ccb *start_ccb)
 612 {
 613         struct targ_softc *softc;
 614         struct targ_cmd_descr *descr, *next_descr;
 615         int error;
 616
 617         softc = (struct targ_softc *)periph->softc;
 618         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targstart %p\n", start_ccb));
 619
 620         descr = TAILQ_FIRST(&softc->work_queue);
 621         if (descr == NULL) {
 622                 xpt_release_ccb(start_ccb);
 623         } else {
 624                 TAILQ_REMOVE(&softc->work_queue, descr, tqe);
 625                 next_descr = TAILQ_FIRST(&softc->work_queue);
 626
 627                 /* Initiate a transaction using the descr and supplied CCB */
 628                 error = targusermerge(softc, descr, start_ccb);
 629                 if (error == 0)
 630                         error = targsendccb(softc, start_ccb, descr);
 631                 if (error != 0) {
 632                         xpt_print(periph->path,
 633                             "targsendccb failed, err %d\n", error);
 634                         xpt_release_ccb(start_ccb);
 635                         suword(&descr->user_ccb->ccb_h.status,
 636                                CAM_REQ_CMP_ERR);
 637                         TAILQ_INSERT_TAIL(&softc->abort_queue, descr, tqe);
 638                         notify_user(softc);
 639                 }
 640
 641                 /* If we have more work to do, stay scheduled */
 642                 if (next_descr != NULL)
 643                         xpt_schedule(periph, next_descr->priority);
 644         }
 645 }
 646
 647 static int
 648 targusermerge(struct targ_softc *softc, struct targ_cmd_descr *descr,
 649               union ccb *ccb)
 650 {
 651         struct ccb_hdr *u_ccbh, *k_ccbh;
 652         size_t ccb_len;
 653         int error;
 654
 655         u_ccbh = &descr->user_ccb->ccb_h;
 656         k_ccbh = &ccb->ccb_h;
 657
 658         /*
 659          * There are some fields in the CCB header that need to be
 660          * preserved, the rest we get from the user ccb. (See xpt_merge_ccb)
 661          */
 662         xpt_setup_ccb(k_ccbh, softc->path, descr->priority);
 663         k_ccbh->retry_count = fuword32(&u_ccbh->retry_count);
 664         k_ccbh->func_code = descr->func_code;
 665         k_ccbh->flags = fuword32(&u_ccbh->flags);
 666         k_ccbh->timeout = fuword32(&u_ccbh->timeout);
 667         ccb_len = targccblen(k_ccbh->func_code) - sizeof(struct ccb_hdr);
 668         error = copyin(u_ccbh + 1, k_ccbh + 1, ccb_len);
 669         if (error != 0) {
 670                 k_ccbh->status = CAM_REQ_CMP_ERR;
 671                 return (error);
 672         }
 673
 674         /* Translate usermode abort_ccb pointer to its kernel counterpart */
 675         if (k_ccbh->func_code == XPT_ABORT) {
 676                 struct ccb_abort *cab;
 677                 struct ccb_hdr *ccb_h;
 678
 679                 cab = (struct ccb_abort *)ccb;
 680                 TAILQ_FOREACH(ccb_h, &softc->pending_ccb_queue,
 681                     periph_links.tqe) {
 682                         struct targ_cmd_descr *ab_descr;
 683
 684                         ab_descr = (struct targ_cmd_descr *)ccb_h->targ_descr;
 685                         if (ab_descr->user_ccb == cab->abort_ccb) {
 686                                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 687                                           ("Changing abort for %p to %p\n",
 688                                           cab->abort_ccb, ccb_h));
 689                                 cab->abort_ccb = (union ccb *)ccb_h;
 690                                 break;
 691                         }
 692                 }
 693                 /* CCB not found, set appropriate status */
 694                 if (ccb_h == NULL) {
 695                         k_ccbh->status = CAM_PATH_INVALID;
 696                         error = ESRCH;
 697                 }
 698         }
 699
 700         return (error);
 701 }
 702
 703 /* Build and send a kernel CCB formed from descr->user_ccb */
 704 static int
 705 targsendccb(struct targ_softc *softc, union ccb *ccb,
 706             struct targ_cmd_descr *descr)
 707 {
 708         struct cam_periph_map_info *mapinfo;
 709         struct ccb_hdr *ccb_h;
 710         int error;
 711
 712         ccb_h = &ccb->ccb_h;
 713         mapinfo = &descr->mapinfo;
 714         mapinfo->num_bufs_used = 0;
 715
 716         /*
 717          * There's no way for the user to have a completion
 718          * function, so we put our own completion function in here.
 719          * We also stash in a reference to our descriptor so targreturnccb()
 720          * can find our mapping info.
 721          */
 722         ccb_h->cbfcnp = targdone;
 723         ccb_h->targ_descr = descr;
 724
 725         if ((ccb_h->func_code == XPT_CONT_TARGET_IO) ||
 726             (ccb_h->func_code == XPT_DEV_MATCH)) {
 727
 728                 error = cam_periph_mapmem(ccb, mapinfo);
 729
 730                 /*
 731                  * cam_periph_mapmem returned an error, we can't continue.
 732                  * Return the error to the user.
 733                  */
 734                 if (error) {
 735                         ccb_h->status = CAM_REQ_CMP_ERR;
 736                         mapinfo->num_bufs_used = 0;
 737                         return (error);
 738                 }
 739         }
 740
 741         /*
 742          * Once queued on the pending CCB list, this CCB will be protected
 743          * by our error recovery handler.
 744          */
 745         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("sendccb %p\n", ccb));
 746         if (XPT_FC_IS_QUEUED(ccb)) {
 747                 TAILQ_INSERT_TAIL(&softc->pending_ccb_queue, ccb_h,
 748                                   periph_links.tqe);
 749         }
 750         xpt_action(ccb);
 751
 752         return (0);
 753 }
 754
 755 /* Completion routine for CCBs (called at splsoftcam) */
 756 static void
 757 targdone(struct cam_periph *periph, union ccb *done_ccb)
 758 {
 759         struct targ_softc *softc;
 760         cam_status status;
 761
 762         CAM_DEBUG(periph->path, CAM_DEBUG_PERIPH, ("targdone %p\n", done_ccb));
 763         softc = (struct targ_softc *)periph->softc;
 764         TAILQ_REMOVE(&softc->pending_ccb_queue, &done_ccb->ccb_h,
 765                      periph_links.tqe);
 766         status = done_ccb->ccb_h.status & CAM_STATUS_MASK;
 767
 768         /* If we're no longer enabled, throw away CCB */
 769         if ((softc->state & TARG_STATE_LUN_ENABLED) == 0) {
 770                 targfreeccb(softc, done_ccb);
 771                 return;
 772         }
 773         /* abort_all_pending() waits for pending queue to be empty */
 774         if (TAILQ_EMPTY(&softc->pending_ccb_queue))
 775                 wakeup(&softc->pending_ccb_queue);
 776
 777         switch (done_ccb->ccb_h.func_code) {
 778         /* All FC_*_QUEUED CCBs go back to userland */
 779         case XPT_IMMED_NOTIFY:
 780         case XPT_IMMEDIATE_NOTIFY:
 781         case XPT_ACCEPT_TARGET_IO:
 782         case XPT_CONT_TARGET_IO:
 783                 TAILQ_INSERT_TAIL(&softc->user_ccb_queue, &done_ccb->ccb_h,
 784                                   periph_links.tqe);
 785                 cam_periph_unlock(softc->periph);
 786                 notify_user(softc);
 787                 cam_periph_lock(softc->periph);
 788                 break;
 789         default:
 790                 panic("targdone: impossible xpt opcode %#x",
 791                       done_ccb->ccb_h.func_code);
 792                 /* NOTREACHED */
 793         }
 794 }
 795
 796 /* Return CCBs to the user from the user queue and abort queue */
 797 static int
 798 targread(struct cdev *dev, struct uio *uio, int ioflag)
 799 {
 800         struct descr_queue      *abort_queue;
 801         struct targ_cmd_descr   *user_descr;
 802         struct targ_softc       *softc;
 803         struct ccb_queue  *user_queue;
 804         struct ccb_hdr    *ccb_h;
 805         union  ccb        *user_ccb;
 806         int                read_len, error;
 807
 808         error = 0;
 809         read_len = 0;
 810         devfs_get_cdevpriv((void **)&softc);
 811         user_queue = &softc->user_ccb_queue;
 812         abort_queue = &softc->abort_queue;
 813         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targread\n"));
 814
 815         /* If no data is available, wait or return immediately */
 816         cam_periph_lock(softc->periph);
 817         ccb_h = TAILQ_FIRST(user_queue);
 818         user_descr = TAILQ_FIRST(abort_queue);
 819         while (ccb_h == NULL && user_descr == NULL) {
 820                 if ((ioflag & IO_NDELAY) == 0) {
 821                         error = cam_periph_sleep(softc->periph, user_queue,
 822                             PRIBIO | PCATCH, "targrd", 0);
 823                         ccb_h = TAILQ_FIRST(user_queue);
 824                         user_descr = TAILQ_FIRST(abort_queue);
 825                         if (error != 0) {
 826                                 if (error == ERESTART) {
 827                                         continue;
 828                                 } else {
 829                                         goto read_fail;
 830                                 }
 831                         }
 832                 } else {
 833                         cam_periph_unlock(softc->periph);
 834                         return (EAGAIN);
 835                 }
 836         }
 837
 838         /* Data is available so fill the user's buffer */
 839         while (ccb_h != NULL) {
 840                 struct targ_cmd_descr *descr;
 841
 842                 if (uio->uio_resid < sizeof(user_ccb))
 843                         break;
 844                 TAILQ_REMOVE(user_queue, ccb_h, periph_links.tqe);
 845                 descr = (struct targ_cmd_descr *)ccb_h->targ_descr;
 846                 user_ccb = descr->user_ccb;
 847                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 848                           ("targread ccb %p (%p)\n", ccb_h, user_ccb));
 849                 error = targreturnccb(softc, (union ccb *)ccb_h);
 850                 if (error != 0)
 851                         goto read_fail;
 852                 cam_periph_unlock(softc->periph);
 853                 error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
 854                 cam_periph_lock(softc->periph);
 855                 if (error != 0)
 856                         goto read_fail;
 857                 read_len += sizeof(user_ccb);
 858
 859                 ccb_h = TAILQ_FIRST(user_queue);
 860         }
 861
 862         /* Flush out any aborted descriptors */
 863         while (user_descr != NULL) {
 864                 if (uio->uio_resid < sizeof(user_ccb))
 865                         break;
 866                 TAILQ_REMOVE(abort_queue, user_descr, tqe);
 867                 user_ccb = user_descr->user_ccb;
 868                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 869                           ("targread aborted descr %p (%p)\n",
 870                           user_descr, user_ccb));
 871                 suword(&user_ccb->ccb_h.status, CAM_REQ_ABORTED);
 872                 cam_periph_unlock(softc->periph);
 873                 error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
 874                 cam_periph_lock(softc->periph);
 875                 if (error != 0)
 876                         goto read_fail;
 877                 read_len += sizeof(user_ccb);
 878
 879                 user_descr = TAILQ_FIRST(abort_queue);
 880         }
 881
 882         /*
 883          * If we've successfully read some amount of data, don't report an
 884          * error.  If the error is persistent, it will be reported on the
 885          * next read().
 886          */
 887         if (read_len == 0 && uio->uio_resid != 0)
 888                 error = ENOSPC;
 889
 890 read_fail:
 891         cam_periph_unlock(softc->periph);
 892         return (error);
 893 }
 894
 895 /* Copy completed ccb back to the user */
 896 static int
 897 targreturnccb(struct targ_softc *softc, union ccb *ccb)
 898 {
 899         struct targ_cmd_descr *descr;
 900         struct ccb_hdr *u_ccbh;
 901         size_t ccb_len;
 902         int error;
 903
 904         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targreturnccb %p\n", ccb));
 905         descr = (struct targ_cmd_descr *)ccb->ccb_h.targ_descr;
 906         u_ccbh = &descr->user_ccb->ccb_h;
 907
 908         /* Copy out the central portion of the ccb_hdr */
 909         copyout(&ccb->ccb_h.retry_count, &u_ccbh->retry_count,
 910                 offsetof(struct ccb_hdr, periph_priv) -
 911                 offsetof(struct ccb_hdr, retry_count));
 912
 913         /* Copy out the rest of the ccb (after the ccb_hdr) */
 914         ccb_len = targccblen(ccb->ccb_h.func_code) - sizeof(struct ccb_hdr);
 915         if (descr->mapinfo.num_bufs_used != 0)
 916                 cam_periph_unmapmem(ccb, &descr->mapinfo);
 917         error = copyout(&ccb->ccb_h + 1, u_ccbh + 1, ccb_len);
 918         if (error != 0) {
 919                 xpt_print(softc->path,
 920                     "targreturnccb - CCB copyout failed (%d)\n", error);
 921         }
 922         /* Free CCB or send back to devq. */
 923         targfreeccb(softc, ccb);
 924
 925         return (error);
 926 }
 927
 928 static union ccb *
 929 targgetccb(struct targ_softc *softc, xpt_opcode type, int priority)
 930 {
 931         union ccb *ccb;
 932         int ccb_len;
 933
 934         ccb_len = targccblen(type);
 935         ccb = malloc(ccb_len, M_TARG, M_NOWAIT);
 936         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("getccb %p\n", ccb));
 937         if (ccb == NULL) {
 938                 return (ccb);
 939         }
 940         xpt_setup_ccb(&ccb->ccb_h, softc->path, priority);
 941         ccb->ccb_h.func_code = type;
 942         ccb->ccb_h.cbfcnp = targdone;
 943         ccb->ccb_h.targ_descr = targgetdescr(softc);
 944         if (ccb->ccb_h.targ_descr == NULL) {
 945                 free (ccb, M_TARG);
 946                 ccb = NULL;
 947         }
 948         return (ccb);
 949 }
 950
 951 static void
 952 targfreeccb(struct targ_softc *softc, union ccb *ccb)
 953 {
 954         CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH, ("targfreeccb descr %p and\n",
 955                         ccb->ccb_h.targ_descr));
 956         free(ccb->ccb_h.targ_descr, M_TARG);
 957
 958         switch (ccb->ccb_h.func_code) {
 959         case XPT_ACCEPT_TARGET_IO:
 960         case XPT_IMMED_NOTIFY:
 961         case XPT_IMMEDIATE_NOTIFY:
 962                 CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH, ("freeing ccb %p\n", ccb));
 963                 free(ccb, M_TARG);
 964                 break;
 965         default:
 966                 /* Send back CCB if we got it from the periph */
 967                 if (XPT_FC_IS_QUEUED(ccb)) {
 968                         CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH,
 969                                         ("returning queued ccb %p\n", ccb));
 970                         xpt_release_ccb(ccb);
 971                 } else {
 972                         CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH,
 973                                         ("freeing ccb %p\n", ccb));
 974                         free(ccb, M_TARG);
 975                 }
 976                 break;
 977         }
 978 }
 979
 980 static struct targ_cmd_descr *
 981 targgetdescr(struct targ_softc *softc)
 982 {
 983         struct targ_cmd_descr *descr;
 984
 985         descr = malloc(sizeof(*descr), M_TARG,
 986                M_NOWAIT);
 987         if (descr) {
 988                 descr->mapinfo.num_bufs_used = 0;
 989         }
 990         return (descr);
 991 }
 992
 993 static void
 994 targinit(void)
 995 {
 996         struct cdev *dev;
 997
 998         /* Add symbolic link to targ0 for compatibility. */
 999         dev = make_dev(&targ_cdevsw, 0, UID_ROOT, GID_WHEEL, 0600, "targ");
1000         make_dev_alias(dev, "targ0");
1001 }
1002
1003 static void
1004 targasync(void *callback_arg, u_int32_t code, struct cam_path *path, void *arg)
1005 {
1006         /* All events are handled in usermode by INOTs */
1007         panic("targasync() called, should be an INOT instead");
1008 }
1009
1010 /* Cancel all pending requests and CCBs awaiting work. */
1011 static void
1012 abort_all_pending(struct targ_softc *softc)
1013 {
1014         struct targ_cmd_descr   *descr;
1015         struct ccb_abort         cab;
1016         struct ccb_hdr          *ccb_h;
1017
1018         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("abort_all_pending\n"));
1019
1020         /* First abort the descriptors awaiting resources */
1021         while ((descr = TAILQ_FIRST(&softc->work_queue)) != NULL) {
1022                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
1023                           ("Aborting descr from workq %p\n", descr));
1024                 TAILQ_REMOVE(&softc->work_queue, descr, tqe);
1025                 TAILQ_INSERT_TAIL(&softc->abort_queue, descr, tqe);
1026         }
1027
1028         /*
1029          * Then abort all pending CCBs.
1030          * targdone() will return the aborted CCB via user_ccb_queue
1031          */
1032         xpt_setup_ccb(&cab.ccb_h, softc->path, CAM_PRIORITY_NORMAL);
1033         cab.ccb_h.func_code = XPT_ABORT;
1034         cab.ccb_h.status = CAM_REQ_CMP_ERR;
1035         TAILQ_FOREACH(ccb_h, &softc->pending_ccb_queue, periph_links.tqe) {
1036                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
1037                           ("Aborting pending CCB %p\n", ccb_h));
1038                 cab.abort_ccb = (union ccb *)ccb_h;
1039                 xpt_action((union ccb *)&cab);
1040                 if (cab.ccb_h.status != CAM_REQ_CMP) {
1041                         xpt_print(cab.ccb_h.path,
1042                             "Unable to abort CCB, status %#x\n",
1043                             cab.ccb_h.status);
1044                 }
1045         }
1046
1047         /* If we aborted at least one pending CCB ok, wait for it. */
1048         if (cab.ccb_h.status == CAM_REQ_CMP) {
1049                 cam_periph_sleep(softc->periph, &softc->pending_ccb_queue,
1050                        PRIBIO | PCATCH, "tgabrt", 0);
1051         }
1052
1053         /* If we aborted anything from the work queue, wakeup user. */
1054         if (!TAILQ_EMPTY(&softc->user_ccb_queue)
1055          || !TAILQ_EMPTY(&softc->abort_queue)) {
1056                 cam_periph_unlock(softc->periph);
1057                 notify_user(softc);
1058                 cam_periph_lock(softc->periph);
1059         }
1060 }
1061
1062 /* Notify the user that data is ready */
1063 static void
1064 notify_user(struct targ_softc *softc)
1065 {
1066         /*
1067          * Notify users sleeping via poll(), kqueue(), and
1068          * blocking read().
1069          */
1070         selwakeuppri(&softc->read_select, PRIBIO);
1071         KNOTE_UNLOCKED(&softc->read_select.si_note, 0);
1072         wakeup(&softc->user_ccb_queue);
1073 }
1074
1075 /* Convert CAM status to errno values */
1076 static int
1077 targcamstatus(cam_status status)
1078 {
1079         switch (status & CAM_STATUS_MASK) {
1080         case CAM_REQ_CMP:       /* CCB request completed without error */
1081                 return (0);
1082         case CAM_REQ_INPROG:    /* CCB request is in progress */
1083                 return (EINPROGRESS);
1084         case CAM_REQ_CMP_ERR:   /* CCB request completed with an error */
1085                 return (EIO);
1086         case CAM_PROVIDE_FAIL:  /* Unable to provide requested capability */
1087                 return (ENOTTY);
1088         case CAM_FUNC_NOTAVAIL: /* The requested function is not available */
1089                 return (ENOTSUP);
1090         case CAM_LUN_ALRDY_ENA: /* LUN is already enabled for target mode */
1091                 return (EADDRINUSE);
1092         case CAM_PATH_INVALID:  /* Supplied Path ID is invalid */
1093         case CAM_DEV_NOT_THERE: /* SCSI Device Not Installed/there */
1094                 return (ENOENT);
1095         case CAM_REQ_ABORTED:   /* CCB request aborted by the host */
1096                 return (ECANCELED);
1097         case CAM_CMD_TIMEOUT:   /* Command timeout */
1098                 return (ETIMEDOUT);
1099         case CAM_REQUEUE_REQ:   /* Requeue to preserve transaction ordering */
1100                 return (EAGAIN);
1101         case CAM_REQ_INVALID:   /* CCB request was invalid */
1102                 return (EINVAL);
1103         case CAM_RESRC_UNAVAIL: /* Resource Unavailable */
1104                 return (ENOMEM);
1105         case CAM_BUSY:          /* CAM subsystem is busy */
1106         case CAM_UA_ABORT:      /* Unable to abort CCB request */
1107                 return (EBUSY);
1108         default:
1109                 return (ENXIO);
1110         }
1111 }
1112
1113 static size_t
1114 targccblen(xpt_opcode func_code)
1115 {
1116         int len;
1117
1118         /* Codes we expect to see as a target */
1119         switch (func_code) {
1120         case XPT_CONT_TARGET_IO:
1121         case XPT_SCSI_IO:
1122                 len = sizeof(struct ccb_scsiio);
1123                 break;
1124         case XPT_ACCEPT_TARGET_IO:
1125                 len = sizeof(struct ccb_accept_tio);
1126                 break;
1127         case XPT_IMMED_NOTIFY:
1128                 len = sizeof(struct ccb_immed_notify);
1129                 break;
1130         case XPT_IMMEDIATE_NOTIFY:
1131                 len = sizeof(struct ccb_immediate_notify);
1132                 break;
1133         case XPT_REL_SIMQ:
1134                 len = sizeof(struct ccb_relsim);
1135                 break;
1136         case XPT_PATH_INQ:
1137                 len = sizeof(struct ccb_pathinq);
1138                 break;
1139         case XPT_DEBUG:
1140                 len = sizeof(struct ccb_debug);
1141                 break;
1142         case XPT_ABORT:
1143                 len = sizeof(struct ccb_abort);
1144                 break;
1145         case XPT_EN_LUN:
1146                 len = sizeof(struct ccb_en_lun);
1147                 break;
1148         default:
1149                 len = sizeof(union ccb);
1150                 break;
1151         }
1152
1153         return (len);
1154 }