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                 struct cam_sim          *sim;
 240
 241                 new_lun = (struct ioc_enable_lun *)addr;
 242                 status = xpt_create_path_unlocked(&path, /*periph*/NULL,
 243                                                   new_lun->path_id,
 244                                                   new_lun->target_id,
 245                                                   new_lun->lun_id);
 246                 if (status != CAM_REQ_CMP) {
 247                         printf("Couldn't create path, status %#x\n", status);
 248                         break;
 249                 }
 250                 sim = xpt_path_sim(path);
 251                 mtx_lock(sim->mtx);
 252                 status = targenable(softc, path, new_lun->grp6_len,
 253                                     new_lun->grp7_len);
 254                 xpt_free_path(path);
 255                 mtx_unlock(sim->mtx);
 256                 break;
 257         }
 258         case TARGIOCDISABLE:
 259                 if (softc->periph == NULL) {
 260                         status = CAM_DEV_NOT_THERE;
 261                         break;
 262                 }
 263                 cam_periph_lock(softc->periph);
 264                 status = targdisable(softc);
 265                 cam_periph_unlock(softc->periph);
 266                 break;
 267         case TARGIOCDEBUG:
 268         {
 269                 struct ccb_debug cdbg;
 270
 271                 /* If no periph available, disallow debugging changes */
 272                 if ((softc->state & TARG_STATE_LUN_ENABLED) == 0) {
 273                         status = CAM_DEV_NOT_THERE;
 274                         break;
 275                 }
 276                 bzero(&cdbg, sizeof cdbg);
 277                 if (*((int *)addr) != 0)
 278                         cdbg.flags = CAM_DEBUG_PERIPH;
 279                 else
 280                         cdbg.flags = CAM_DEBUG_NONE;
 281                 cam_periph_lock(softc->periph);
 282                 xpt_setup_ccb(&cdbg.ccb_h, softc->path, CAM_PRIORITY_NORMAL);
 283                 cdbg.ccb_h.func_code = XPT_DEBUG;
 284                 cdbg.ccb_h.cbfcnp = targdone;
 285
 286                 xpt_action((union ccb *)&cdbg);
 287                 cam_periph_unlock(softc->periph);
 288                 status = cdbg.ccb_h.status & CAM_STATUS_MASK;
 289                 break;
 290         }
 291         default:
 292                 status = CAM_PROVIDE_FAIL;
 293                 break;
 294         }
 295
 296         return (targcamstatus(status));
 297 }
 298
 299 /* Writes are always ready, reads wait for user_ccb_queue or abort_queue */
 300 static int
 301 targpoll(struct cdev *dev, int poll_events, struct thread *td)
 302 {
 303         struct targ_softc *softc;
 304         int     revents;
 305
 306         devfs_get_cdevpriv((void **)&softc);
 307
 308         /* Poll for write() is always ok. */
 309         revents = poll_events & (POLLOUT | POLLWRNORM);
 310         if ((poll_events & (POLLIN | POLLRDNORM)) != 0) {
 311                 /* Poll for read() depends on user and abort queues. */
 312                 cam_periph_lock(softc->periph);
 313                 if (!TAILQ_EMPTY(&softc->user_ccb_queue) ||
 314                     !TAILQ_EMPTY(&softc->abort_queue)) {
 315                         revents |= poll_events & (POLLIN | POLLRDNORM);
 316                 }
 317                 cam_periph_unlock(softc->periph);
 318                 /* Only sleep if the user didn't poll for write. */
 319                 if (revents == 0)
 320                         selrecord(td, &softc->read_select);
 321         }
 322
 323         return (revents);
 324 }
 325
 326 static int
 327 targkqfilter(struct cdev *dev, struct knote *kn)
 328 {
 329         struct  targ_softc *softc;
 330
 331         devfs_get_cdevpriv((void **)&softc);
 332         kn->kn_hook = (caddr_t)softc;
 333         kn->kn_fop = &targread_filtops;
 334         knlist_add(&softc->read_select.si_note, kn, 0);
 335         return (0);
 336 }
 337
 338 static void
 339 targreadfiltdetach(struct knote *kn)
 340 {
 341         struct  targ_softc *softc;
 342
 343         softc = (struct targ_softc *)kn->kn_hook;
 344         knlist_remove(&softc->read_select.si_note, kn, 0);
 345 }
 346
 347 /* Notify the user's kqueue when the user queue or abort queue gets a CCB */
 348 static int
 349 targreadfilt(struct knote *kn, long hint)
 350 {
 351         struct targ_softc *softc;
 352         int     retval;
 353
 354         softc = (struct targ_softc *)kn->kn_hook;
 355         cam_periph_lock(softc->periph);
 356         retval = !TAILQ_EMPTY(&softc->user_ccb_queue) ||
 357                  !TAILQ_EMPTY(&softc->abort_queue);
 358         cam_periph_unlock(softc->periph);
 359         return (retval);
 360 }
 361
 362 /* Send the HBA the enable/disable message */
 363 static cam_status
 364 targendislun(struct cam_path *path, int enable, int grp6_len, int grp7_len)
 365 {
 366         struct ccb_en_lun en_ccb;
 367         cam_status        status;
 368
 369         /* Tell the lun to begin answering selects */
 370         xpt_setup_ccb(&en_ccb.ccb_h, path, CAM_PRIORITY_NORMAL);
 371         en_ccb.ccb_h.func_code = XPT_EN_LUN;
 372         /* Don't need support for any vendor specific commands */
 373         en_ccb.grp6_len = grp6_len;
 374         en_ccb.grp7_len = grp7_len;
 375         en_ccb.enable = enable ? 1 : 0;
 376         xpt_action((union ccb *)&en_ccb);
 377         status = en_ccb.ccb_h.status & CAM_STATUS_MASK;
 378         if (status != CAM_REQ_CMP) {
 379                 xpt_print(path, "%sable lun CCB rejected, status %#x\n",
 380                     enable ? "en" : "dis", status);
 381         }
 382         return (status);
 383 }
 384
 385 /* Enable target mode on a LUN, given its path */
 386 static cam_status
 387 targenable(struct targ_softc *softc, struct cam_path *path, int grp6_len,
 388            int grp7_len)
 389 {
 390         struct cam_periph *periph;
 391         struct ccb_pathinq cpi;
 392         cam_status         status;
 393
 394         if ((softc->state & TARG_STATE_LUN_ENABLED) != 0)
 395                 return (CAM_LUN_ALRDY_ENA);
 396
 397         /* Make sure SIM supports target mode */
 398         xpt_setup_ccb(&cpi.ccb_h, path, CAM_PRIORITY_NORMAL);
 399         cpi.ccb_h.func_code = XPT_PATH_INQ;
 400         xpt_action((union ccb *)&cpi);
 401         status = cpi.ccb_h.status & CAM_STATUS_MASK;
 402         if (status != CAM_REQ_CMP) {
 403                 printf("pathinq failed, status %#x\n", status);
 404                 goto enable_fail;
 405         }
 406         if ((cpi.target_sprt & PIT_PROCESSOR) == 0) {
 407                 printf("controller does not support target mode\n");
 408                 status = CAM_FUNC_NOTAVAIL;
 409                 goto enable_fail;
 410         }
 411
 412         /* Destroy any periph on our path if it is disabled */
 413         periph = cam_periph_find(path, "targ");
 414         if (periph != NULL) {
 415                 struct targ_softc *del_softc;
 416
 417                 del_softc = (struct targ_softc *)periph->softc;
 418                 if ((del_softc->state & TARG_STATE_LUN_ENABLED) == 0) {
 419                         cam_periph_invalidate(del_softc->periph);
 420                         del_softc->periph = NULL;
 421                 } else {
 422                         printf("Requested path still in use by targ%d\n",
 423                                periph->unit_number);
 424                         status = CAM_LUN_ALRDY_ENA;
 425                         goto enable_fail;
 426                 }
 427         }
 428
 429         /* Create a periph instance attached to this path */
 430         status = cam_periph_alloc(targctor, NULL, targdtor, targstart,
 431                         "targ", CAM_PERIPH_BIO, path, targasync, 0, softc);
 432         if (status != CAM_REQ_CMP) {
 433                 printf("cam_periph_alloc failed, status %#x\n", status);
 434                 goto enable_fail;
 435         }
 436
 437         /* Ensure that the periph now exists. */
 438         if (cam_periph_find(path, "targ") == NULL) {
 439                 panic("targenable: succeeded but no periph?");
 440                 /* NOTREACHED */
 441         }
 442
 443         /* Send the enable lun message */
 444         status = targendislun(path, /*enable*/1, grp6_len, grp7_len);
 445         if (status != CAM_REQ_CMP) {
 446                 printf("enable lun failed, status %#x\n", status);
 447                 goto enable_fail;
 448         }
 449         softc->state |= TARG_STATE_LUN_ENABLED;
 450
 451 enable_fail:
 452         return (status);
 453 }
 454
 455 /* Disable this softc's target instance if enabled */
 456 static cam_status
 457 targdisable(struct targ_softc *softc)
 458 {
 459         cam_status status;
 460
 461         if ((softc->state & TARG_STATE_LUN_ENABLED) == 0)
 462                 return (CAM_REQ_CMP);
 463
 464         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targdisable\n"));
 465
 466         /* Abort any ccbs pending on the controller */
 467         abort_all_pending(softc);
 468
 469         /* Disable this lun */
 470         status = targendislun(softc->path, /*enable*/0,
 471                               /*grp6_len*/0, /*grp7_len*/0);
 472         if (status == CAM_REQ_CMP)
 473                 softc->state &= ~TARG_STATE_LUN_ENABLED;
 474         else
 475                 printf("Disable lun failed, status %#x\n", status);
 476
 477         return (status);
 478 }
 479
 480 /* Initialize a periph (called from cam_periph_alloc) */
 481 static cam_status
 482 targctor(struct cam_periph *periph, void *arg)
 483 {
 484         struct targ_softc *softc;
 485
 486         /* Store pointer to softc for periph-driven routines */
 487         softc = (struct targ_softc *)arg;
 488         periph->softc = softc;
 489         softc->periph = periph;
 490         softc->path = periph->path;
 491         return (CAM_REQ_CMP);
 492 }
 493
 494 static void
 495 targdtor(struct cam_periph *periph)
 496 {
 497         struct targ_softc     *softc;
 498         struct ccb_hdr        *ccb_h;
 499         struct targ_cmd_descr *descr;
 500
 501         softc = (struct targ_softc *)periph->softc;
 502
 503         /*
 504          * targdisable() aborts CCBs back to the user and leaves them
 505          * on user_ccb_queue and abort_queue in case the user is still
 506          * interested in them.  We free them now.
 507          */
 508         while ((ccb_h = TAILQ_FIRST(&softc->user_ccb_queue)) != NULL) {
 509                 TAILQ_REMOVE(&softc->user_ccb_queue, ccb_h, periph_links.tqe);
 510                 targfreeccb(softc, (union ccb *)ccb_h);
 511         }
 512         while ((descr = TAILQ_FIRST(&softc->abort_queue)) != NULL) {
 513                 TAILQ_REMOVE(&softc->abort_queue, descr, tqe);
 514                 free(descr, M_TARG);
 515         }
 516
 517         softc->periph = NULL;
 518         softc->path = NULL;
 519         periph->softc = NULL;
 520 }
 521
 522 /* Receive CCBs from user mode proc and send them to the HBA */
 523 static int
 524 targwrite(struct cdev *dev, struct uio *uio, int ioflag)
 525 {
 526         union ccb *user_ccb;
 527         struct targ_softc *softc;
 528         struct targ_cmd_descr *descr;
 529         int write_len, error;
 530         int func_code, priority;
 531
 532         devfs_get_cdevpriv((void **)&softc);
 533         write_len = error = 0;
 534         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 535                   ("write - uio_resid %zd\n", uio->uio_resid));
 536         while (uio->uio_resid >= sizeof(user_ccb) && error == 0) {
 537                 union ccb *ccb;
 538
 539                 error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
 540                 if (error != 0) {
 541                         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 542                                   ("write - uiomove failed (%d)\n", error));
 543                         break;
 544                 }
 545                 priority = fuword32(&user_ccb->ccb_h.pinfo.priority);
 546                 if (priority == CAM_PRIORITY_NONE) {
 547                         error = EINVAL;
 548                         break;
 549                 }
 550                 func_code = fuword32(&user_ccb->ccb_h.func_code);
 551                 switch (func_code) {
 552                 case XPT_ACCEPT_TARGET_IO:
 553                 case XPT_IMMED_NOTIFY:
 554                 case XPT_IMMEDIATE_NOTIFY:
 555                         cam_periph_lock(softc->periph);
 556                         ccb = targgetccb(softc, func_code, priority);
 557                         descr = (struct targ_cmd_descr *)ccb->ccb_h.targ_descr;
 558                         descr->user_ccb = user_ccb;
 559                         descr->func_code = func_code;
 560                         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 561                                   ("Sent ATIO/INOT (%p)\n", user_ccb));
 562                         xpt_action(ccb);
 563                         TAILQ_INSERT_TAIL(&softc->pending_ccb_queue,
 564                                           &ccb->ccb_h,
 565                                           periph_links.tqe);
 566                         cam_periph_unlock(softc->periph);
 567                         break;
 568                 default:
 569                         cam_periph_lock(softc->periph);
 570                         if ((func_code & XPT_FC_QUEUED) != 0) {
 571                                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 572                                           ("Sending queued ccb %#x (%p)\n",
 573                                           func_code, user_ccb));
 574                                 descr = targgetdescr(softc);
 575                                 descr->user_ccb = user_ccb;
 576                                 descr->priority = priority;
 577                                 descr->func_code = func_code;
 578                                 TAILQ_INSERT_TAIL(&softc->work_queue,
 579                                                   descr, tqe);
 580                                 xpt_schedule(softc->periph, priority);
 581                         } else {
 582                                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 583                                           ("Sending inline ccb %#x (%p)\n",
 584                                           func_code, user_ccb));
 585                                 ccb = targgetccb(softc, func_code, priority);
 586                                 descr = (struct targ_cmd_descr *)
 587                                          ccb->ccb_h.targ_descr;
 588                                 descr->user_ccb = user_ccb;
 589                                 descr->priority = priority;
 590                                 descr->func_code = func_code;
 591                                 if (targusermerge(softc, descr, ccb) != EFAULT)
 592                                         targsendccb(softc, ccb, descr);
 593                                 targreturnccb(softc, ccb);
 594                         }
 595                         cam_periph_unlock(softc->periph);
 596                         break;
 597                 }
 598                 write_len += sizeof(user_ccb);
 599         }
 600
 601         /*
 602          * If we've successfully taken in some amount of
 603          * data, return success for that data first.  If
 604          * an error is persistent, it will be reported
 605          * on the next write.
 606          */
 607         if (error != 0 && write_len == 0)
 608                 return (error);
 609         if (write_len == 0 && uio->uio_resid != 0)
 610                 return (ENOSPC);
 611         return (0);
 612 }
 613
 614 /* Process requests (descrs) via the periph-supplied CCBs */
 615 static void
 616 targstart(struct cam_periph *periph, union ccb *start_ccb)
 617 {
 618         struct targ_softc *softc;
 619         struct targ_cmd_descr *descr, *next_descr;
 620         int error;
 621
 622         softc = (struct targ_softc *)periph->softc;
 623         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targstart %p\n", start_ccb));
 624
 625         descr = TAILQ_FIRST(&softc->work_queue);
 626         if (descr == NULL) {
 627                 xpt_release_ccb(start_ccb);
 628         } else {
 629                 TAILQ_REMOVE(&softc->work_queue, descr, tqe);
 630                 next_descr = TAILQ_FIRST(&softc->work_queue);
 631
 632                 /* Initiate a transaction using the descr and supplied CCB */
 633                 error = targusermerge(softc, descr, start_ccb);
 634                 if (error == 0)
 635                         error = targsendccb(softc, start_ccb, descr);
 636                 if (error != 0) {
 637                         xpt_print(periph->path,
 638                             "targsendccb failed, err %d\n", error);
 639                         xpt_release_ccb(start_ccb);
 640                         suword(&descr->user_ccb->ccb_h.status,
 641                                CAM_REQ_CMP_ERR);
 642                         TAILQ_INSERT_TAIL(&softc->abort_queue, descr, tqe);
 643                         notify_user(softc);
 644                 }
 645
 646                 /* If we have more work to do, stay scheduled */
 647                 if (next_descr != NULL)
 648                         xpt_schedule(periph, next_descr->priority);
 649         }
 650 }
 651
 652 static int
 653 targusermerge(struct targ_softc *softc, struct targ_cmd_descr *descr,
 654               union ccb *ccb)
 655 {
 656         struct ccb_hdr *u_ccbh, *k_ccbh;
 657         size_t ccb_len;
 658         int error;
 659
 660         u_ccbh = &descr->user_ccb->ccb_h;
 661         k_ccbh = &ccb->ccb_h;
 662
 663         /*
 664          * There are some fields in the CCB header that need to be
 665          * preserved, the rest we get from the user ccb. (See xpt_merge_ccb)
 666          */
 667         xpt_setup_ccb(k_ccbh, softc->path, descr->priority);
 668         k_ccbh->retry_count = fuword32(&u_ccbh->retry_count);
 669         k_ccbh->func_code = descr->func_code;
 670         k_ccbh->flags = fuword32(&u_ccbh->flags);
 671         k_ccbh->timeout = fuword32(&u_ccbh->timeout);
 672         ccb_len = targccblen(k_ccbh->func_code) - sizeof(struct ccb_hdr);
 673         error = copyin(u_ccbh + 1, k_ccbh + 1, ccb_len);
 674         if (error != 0) {
 675                 k_ccbh->status = CAM_REQ_CMP_ERR;
 676                 return (error);
 677         }
 678
 679         /* Translate usermode abort_ccb pointer to its kernel counterpart */
 680         if (k_ccbh->func_code == XPT_ABORT) {
 681                 struct ccb_abort *cab;
 682                 struct ccb_hdr *ccb_h;
 683
 684                 cab = (struct ccb_abort *)ccb;
 685                 TAILQ_FOREACH(ccb_h, &softc->pending_ccb_queue,
 686                     periph_links.tqe) {
 687                         struct targ_cmd_descr *ab_descr;
 688
 689                         ab_descr = (struct targ_cmd_descr *)ccb_h->targ_descr;
 690                         if (ab_descr->user_ccb == cab->abort_ccb) {
 691                                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 692                                           ("Changing abort for %p to %p\n",
 693                                           cab->abort_ccb, ccb_h));
 694                                 cab->abort_ccb = (union ccb *)ccb_h;
 695                                 break;
 696                         }
 697                 }
 698                 /* CCB not found, set appropriate status */
 699                 if (ccb_h == NULL) {
 700                         k_ccbh->status = CAM_PATH_INVALID;
 701                         error = ESRCH;
 702                 }
 703         }
 704
 705         return (error);
 706 }
 707
 708 /* Build and send a kernel CCB formed from descr->user_ccb */
 709 static int
 710 targsendccb(struct targ_softc *softc, union ccb *ccb,
 711             struct targ_cmd_descr *descr)
 712 {
 713         struct cam_periph_map_info *mapinfo;
 714         struct ccb_hdr *ccb_h;
 715         int error;
 716
 717         ccb_h = &ccb->ccb_h;
 718         mapinfo = &descr->mapinfo;
 719         mapinfo->num_bufs_used = 0;
 720
 721         /*
 722          * There's no way for the user to have a completion
 723          * function, so we put our own completion function in here.
 724          * We also stash in a reference to our descriptor so targreturnccb()
 725          * can find our mapping info.
 726          */
 727         ccb_h->cbfcnp = targdone;
 728         ccb_h->targ_descr = descr;
 729
 730         if ((ccb_h->func_code == XPT_CONT_TARGET_IO) ||
 731             (ccb_h->func_code == XPT_DEV_MATCH)) {
 732
 733                 error = cam_periph_mapmem(ccb, mapinfo);
 734
 735                 /*
 736                  * cam_periph_mapmem returned an error, we can't continue.
 737                  * Return the error to the user.
 738                  */
 739                 if (error) {
 740                         ccb_h->status = CAM_REQ_CMP_ERR;
 741                         mapinfo->num_bufs_used = 0;
 742                         return (error);
 743                 }
 744         }
 745
 746         /*
 747          * Once queued on the pending CCB list, this CCB will be protected
 748          * by our error recovery handler.
 749          */
 750         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("sendccb %p\n", ccb));
 751         if (XPT_FC_IS_QUEUED(ccb)) {
 752                 TAILQ_INSERT_TAIL(&softc->pending_ccb_queue, ccb_h,
 753                                   periph_links.tqe);
 754         }
 755         xpt_action(ccb);
 756
 757         return (0);
 758 }
 759
 760 /* Completion routine for CCBs (called at splsoftcam) */
 761 static void
 762 targdone(struct cam_periph *periph, union ccb *done_ccb)
 763 {
 764         struct targ_softc *softc;
 765         cam_status status;
 766
 767         CAM_DEBUG(periph->path, CAM_DEBUG_PERIPH, ("targdone %p\n", done_ccb));
 768         softc = (struct targ_softc *)periph->softc;
 769         TAILQ_REMOVE(&softc->pending_ccb_queue, &done_ccb->ccb_h,
 770                      periph_links.tqe);
 771         status = done_ccb->ccb_h.status & CAM_STATUS_MASK;
 772
 773         /* If we're no longer enabled, throw away CCB */
 774         if ((softc->state & TARG_STATE_LUN_ENABLED) == 0) {
 775                 targfreeccb(softc, done_ccb);
 776                 return;
 777         }
 778         /* abort_all_pending() waits for pending queue to be empty */
 779         if (TAILQ_EMPTY(&softc->pending_ccb_queue))
 780                 wakeup(&softc->pending_ccb_queue);
 781
 782         switch (done_ccb->ccb_h.func_code) {
 783         /* All FC_*_QUEUED CCBs go back to userland */
 784         case XPT_IMMED_NOTIFY:
 785         case XPT_IMMEDIATE_NOTIFY:
 786         case XPT_ACCEPT_TARGET_IO:
 787         case XPT_CONT_TARGET_IO:
 788                 TAILQ_INSERT_TAIL(&softc->user_ccb_queue, &done_ccb->ccb_h,
 789                                   periph_links.tqe);
 790                 cam_periph_unlock(softc->periph);
 791                 notify_user(softc);
 792                 cam_periph_lock(softc->periph);
 793                 break;
 794         default:
 795                 panic("targdone: impossible xpt opcode %#x",
 796                       done_ccb->ccb_h.func_code);
 797                 /* NOTREACHED */
 798         }
 799 }
 800
 801 /* Return CCBs to the user from the user queue and abort queue */
 802 static int
 803 targread(struct cdev *dev, struct uio *uio, int ioflag)
 804 {
 805         struct descr_queue      *abort_queue;
 806         struct targ_cmd_descr   *user_descr;
 807         struct targ_softc       *softc;
 808         struct ccb_queue  *user_queue;
 809         struct ccb_hdr    *ccb_h;
 810         union  ccb        *user_ccb;
 811         int                read_len, error;
 812
 813         error = 0;
 814         read_len = 0;
 815         devfs_get_cdevpriv((void **)&softc);
 816         user_queue = &softc->user_ccb_queue;
 817         abort_queue = &softc->abort_queue;
 818         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targread\n"));
 819
 820         /* If no data is available, wait or return immediately */
 821         cam_periph_lock(softc->periph);
 822         ccb_h = TAILQ_FIRST(user_queue);
 823         user_descr = TAILQ_FIRST(abort_queue);
 824         while (ccb_h == NULL && user_descr == NULL) {
 825                 if ((ioflag & IO_NDELAY) == 0) {
 826                         error = msleep(user_queue, softc->periph->sim->mtx,
 827                             PRIBIO | PCATCH, "targrd", 0);
 828                         ccb_h = TAILQ_FIRST(user_queue);
 829                         user_descr = TAILQ_FIRST(abort_queue);
 830                         if (error != 0) {
 831                                 if (error == ERESTART) {
 832                                         continue;
 833                                 } else {
 834                                         goto read_fail;
 835                                 }
 836                         }
 837                 } else {
 838                         cam_periph_unlock(softc->periph);
 839                         return (EAGAIN);
 840                 }
 841         }
 842
 843         /* Data is available so fill the user's buffer */
 844         while (ccb_h != NULL) {
 845                 struct targ_cmd_descr *descr;
 846
 847                 if (uio->uio_resid < sizeof(user_ccb))
 848                         break;
 849                 TAILQ_REMOVE(user_queue, ccb_h, periph_links.tqe);
 850                 descr = (struct targ_cmd_descr *)ccb_h->targ_descr;
 851                 user_ccb = descr->user_ccb;
 852                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 853                           ("targread ccb %p (%p)\n", ccb_h, user_ccb));
 854                 error = targreturnccb(softc, (union ccb *)ccb_h);
 855                 if (error != 0)
 856                         goto read_fail;
 857                 cam_periph_unlock(softc->periph);
 858                 error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
 859                 cam_periph_lock(softc->periph);
 860                 if (error != 0)
 861                         goto read_fail;
 862                 read_len += sizeof(user_ccb);
 863
 864                 ccb_h = TAILQ_FIRST(user_queue);
 865         }
 866
 867         /* Flush out any aborted descriptors */
 868         while (user_descr != NULL) {
 869                 if (uio->uio_resid < sizeof(user_ccb))
 870                         break;
 871                 TAILQ_REMOVE(abort_queue, user_descr, tqe);
 872                 user_ccb = user_descr->user_ccb;
 873                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 874                           ("targread aborted descr %p (%p)\n",
 875                           user_descr, user_ccb));
 876                 suword(&user_ccb->ccb_h.status, CAM_REQ_ABORTED);
 877                 cam_periph_unlock(softc->periph);
 878                 error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
 879                 cam_periph_lock(softc->periph);
 880                 if (error != 0)
 881                         goto read_fail;
 882                 read_len += sizeof(user_ccb);
 883
 884                 user_descr = TAILQ_FIRST(abort_queue);
 885         }
 886
 887         /*
 888          * If we've successfully read some amount of data, don't report an
 889          * error.  If the error is persistent, it will be reported on the
 890          * next read().
 891          */
 892         if (read_len == 0 && uio->uio_resid != 0)
 893                 error = ENOSPC;
 894
 895 read_fail:
 896         cam_periph_unlock(softc->periph);
 897         return (error);
 898 }
 899
 900 /* Copy completed ccb back to the user */
 901 static int
 902 targreturnccb(struct targ_softc *softc, union ccb *ccb)
 903 {
 904         struct targ_cmd_descr *descr;
 905         struct ccb_hdr *u_ccbh;
 906         size_t ccb_len;
 907         int error;
 908
 909         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targreturnccb %p\n", ccb));
 910         descr = (struct targ_cmd_descr *)ccb->ccb_h.targ_descr;
 911         u_ccbh = &descr->user_ccb->ccb_h;
 912
 913         /* Copy out the central portion of the ccb_hdr */
 914         copyout(&ccb->ccb_h.retry_count, &u_ccbh->retry_count,
 915                 offsetof(struct ccb_hdr, periph_priv) -
 916                 offsetof(struct ccb_hdr, retry_count));
 917
 918         /* Copy out the rest of the ccb (after the ccb_hdr) */
 919         ccb_len = targccblen(ccb->ccb_h.func_code) - sizeof(struct ccb_hdr);
 920         if (descr->mapinfo.num_bufs_used != 0)
 921                 cam_periph_unmapmem(ccb, &descr->mapinfo);
 922         error = copyout(&ccb->ccb_h + 1, u_ccbh + 1, ccb_len);
 923         if (error != 0) {
 924                 xpt_print(softc->path,
 925                     "targreturnccb - CCB copyout failed (%d)\n", error);
 926         }
 927         /* Free CCB or send back to devq. */
 928         targfreeccb(softc, ccb);
 929
 930         return (error);
 931 }
 932
 933 static union ccb *
 934 targgetccb(struct targ_softc *softc, xpt_opcode type, int priority)
 935 {
 936         union ccb *ccb;
 937         int ccb_len;
 938
 939         ccb_len = targccblen(type);
 940         ccb = malloc(ccb_len, M_TARG, M_NOWAIT);
 941         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("getccb %p\n", ccb));
 942         if (ccb == NULL) {
 943                 return (ccb);
 944         }
 945         xpt_setup_ccb(&ccb->ccb_h, softc->path, priority);
 946         ccb->ccb_h.func_code = type;
 947         ccb->ccb_h.cbfcnp = targdone;
 948         ccb->ccb_h.targ_descr = targgetdescr(softc);
 949         if (ccb->ccb_h.targ_descr == NULL) {
 950                 free (ccb, M_TARG);
 951                 ccb = NULL;
 952         }
 953         return (ccb);
 954 }
 955
 956 static void
 957 targfreeccb(struct targ_softc *softc, union ccb *ccb)
 958 {
 959         CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH, ("targfreeccb descr %p and\n",
 960                         ccb->ccb_h.targ_descr));
 961         free(ccb->ccb_h.targ_descr, M_TARG);
 962
 963         switch (ccb->ccb_h.func_code) {
 964         case XPT_ACCEPT_TARGET_IO:
 965         case XPT_IMMED_NOTIFY:
 966         case XPT_IMMEDIATE_NOTIFY:
 967                 CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH, ("freeing ccb %p\n", ccb));
 968                 free(ccb, M_TARG);
 969                 break;
 970         default:
 971                 /* Send back CCB if we got it from the periph */
 972                 if (XPT_FC_IS_QUEUED(ccb)) {
 973                         CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH,
 974                                         ("returning queued ccb %p\n", ccb));
 975                         xpt_release_ccb(ccb);
 976                 } else {
 977                         CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH,
 978                                         ("freeing ccb %p\n", ccb));
 979                         free(ccb, M_TARG);
 980                 }
 981                 break;
 982         }
 983 }
 984
 985 static struct targ_cmd_descr *
 986 targgetdescr(struct targ_softc *softc)
 987 {
 988         struct targ_cmd_descr *descr;
 989
 990         descr = malloc(sizeof(*descr), M_TARG,
 991                M_NOWAIT);
 992         if (descr) {
 993                 descr->mapinfo.num_bufs_used = 0;
 994         }
 995         return (descr);
 996 }
 997
 998 static void
 999 targinit(void)
1000 {
1001         struct cdev *dev;
1002
1003         /* Add symbolic link to targ0 for compatibility. */
1004         dev = make_dev(&targ_cdevsw, 0, UID_ROOT, GID_WHEEL, 0600, "targ");
1005         make_dev_alias(dev, "targ0");
1006 }
1007
1008 static void
1009 targasync(void *callback_arg, u_int32_t code, struct cam_path *path, void *arg)
1010 {
1011         /* All events are handled in usermode by INOTs */
1012         panic("targasync() called, should be an INOT instead");
1013 }
1014
1015 /* Cancel all pending requests and CCBs awaiting work. */
1016 static void
1017 abort_all_pending(struct targ_softc *softc)
1018 {
1019         struct targ_cmd_descr   *descr;
1020         struct ccb_abort         cab;
1021         struct ccb_hdr          *ccb_h;
1022         struct cam_sim          *sim;
1023
1024         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("abort_all_pending\n"));
1025
1026         /* First abort the descriptors awaiting resources */
1027         while ((descr = TAILQ_FIRST(&softc->work_queue)) != NULL) {
1028                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
1029                           ("Aborting descr from workq %p\n", descr));
1030                 TAILQ_REMOVE(&softc->work_queue, descr, tqe);
1031                 TAILQ_INSERT_TAIL(&softc->abort_queue, descr, tqe);
1032         }
1033
1034         /*
1035          * Then abort all pending CCBs.
1036          * targdone() will return the aborted CCB via user_ccb_queue
1037          */
1038         xpt_setup_ccb(&cab.ccb_h, softc->path, CAM_PRIORITY_NORMAL);
1039         cab.ccb_h.func_code = XPT_ABORT;
1040         cab.ccb_h.status = CAM_REQ_CMP_ERR;
1041         TAILQ_FOREACH(ccb_h, &softc->pending_ccb_queue, periph_links.tqe) {
1042                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
1043                           ("Aborting pending CCB %p\n", ccb_h));
1044                 cab.abort_ccb = (union ccb *)ccb_h;
1045                 xpt_action((union ccb *)&cab);
1046                 if (cab.ccb_h.status != CAM_REQ_CMP) {
1047                         xpt_print(cab.ccb_h.path,
1048                             "Unable to abort CCB, status %#x\n",
1049                             cab.ccb_h.status);
1050                 }
1051         }
1052
1053         /* If we aborted at least one pending CCB ok, wait for it. */
1054         if (cab.ccb_h.status == CAM_REQ_CMP) {
1055                 sim = xpt_path_sim(softc->path);
1056                 msleep(&softc->pending_ccb_queue, sim->mtx,
1057                        PRIBIO | PCATCH, "tgabrt", 0);
1058         }
1059
1060         /* If we aborted anything from the work queue, wakeup user. */
1061         if (!TAILQ_EMPTY(&softc->user_ccb_queue)
1062          || !TAILQ_EMPTY(&softc->abort_queue)) {
1063                 cam_periph_unlock(softc->periph);
1064                 notify_user(softc);
1065                 cam_periph_lock(softc->periph);
1066         }
1067 }
1068
1069 /* Notify the user that data is ready */
1070 static void
1071 notify_user(struct targ_softc *softc)
1072 {
1073         /*
1074          * Notify users sleeping via poll(), kqueue(), and
1075          * blocking read().
1076          */
1077         selwakeuppri(&softc->read_select, PRIBIO);
1078         KNOTE_UNLOCKED(&softc->read_select.si_note, 0);
1079         wakeup(&softc->user_ccb_queue);
1080 }
1081
1082 /* Convert CAM status to errno values */
1083 static int
1084 targcamstatus(cam_status status)
1085 {
1086         switch (status & CAM_STATUS_MASK) {
1087         case CAM_REQ_CMP:       /* CCB request completed without error */
1088                 return (0);
1089         case CAM_REQ_INPROG:    /* CCB request is in progress */
1090                 return (EINPROGRESS);
1091         case CAM_REQ_CMP_ERR:   /* CCB request completed with an error */
1092                 return (EIO);
1093         case CAM_PROVIDE_FAIL:  /* Unable to provide requested capability */
1094                 return (ENOTTY);
1095         case CAM_FUNC_NOTAVAIL: /* The requested function is not available */
1096                 return (ENOTSUP);
1097         case CAM_LUN_ALRDY_ENA: /* LUN is already enabled for target mode */
1098                 return (EADDRINUSE);
1099         case CAM_PATH_INVALID:  /* Supplied Path ID is invalid */
1100         case CAM_DEV_NOT_THERE: /* SCSI Device Not Installed/there */
1101                 return (ENOENT);
1102         case CAM_REQ_ABORTED:   /* CCB request aborted by the host */
1103                 return (ECANCELED);
1104         case CAM_CMD_TIMEOUT:   /* Command timeout */
1105                 return (ETIMEDOUT);
1106         case CAM_REQUEUE_REQ:   /* Requeue to preserve transaction ordering */
1107                 return (EAGAIN);
1108         case CAM_REQ_INVALID:   /* CCB request was invalid */
1109                 return (EINVAL);
1110         case CAM_RESRC_UNAVAIL: /* Resource Unavailable */
1111                 return (ENOMEM);
1112         case CAM_BUSY:          /* CAM subsystem is busy */
1113         case CAM_UA_ABORT:      /* Unable to abort CCB request */
1114                 return (EBUSY);
1115         default:
1116                 return (ENXIO);
1117         }
1118 }
1119
1120 static size_t
1121 targccblen(xpt_opcode func_code)
1122 {
1123         int len;
1124
1125         /* Codes we expect to see as a target */
1126         switch (func_code) {
1127         case XPT_CONT_TARGET_IO:
1128         case XPT_SCSI_IO:
1129                 len = sizeof(struct ccb_scsiio);
1130                 break;
1131         case XPT_ACCEPT_TARGET_IO:
1132                 len = sizeof(struct ccb_accept_tio);
1133                 break;
1134         case XPT_IMMED_NOTIFY:
1135                 len = sizeof(struct ccb_immed_notify);
1136                 break;
1137         case XPT_IMMEDIATE_NOTIFY:
1138                 len = sizeof(struct ccb_immediate_notify);
1139                 break;
1140         case XPT_REL_SIMQ:
1141                 len = sizeof(struct ccb_relsim);
1142                 break;
1143         case XPT_PATH_INQ:
1144                 len = sizeof(struct ccb_pathinq);
1145                 break;
1146         case XPT_DEBUG:
1147                 len = sizeof(struct ccb_debug);
1148                 break;
1149         case XPT_ABORT:
1150                 len = sizeof(struct ccb_abort);
1151                 break;
1152         case XPT_EN_LUN:
1153                 len = sizeof(struct ccb_en_lun);
1154                 break;
1155         default:
1156                 len = sizeof(union ccb);
1157                 break;
1158         }
1159
1160         return (len);
1161 }