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