sys/cam/scsi/scsi_target.c

   1 /*-
   2  * Generic SCSI Target Kernel Mode Driver
   3  *
   4  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
   5  *
   6  * Copyright (c) 2002 Nate Lawson.
   7  * Copyright (c) 1998, 1999, 2001, 2002 Justin T. Gibbs.
   8  * All rights reserved.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions, and the following disclaimer,
  15  *    without modification, immediately at the beginning of the file.
  16  * 2. The name of the author may not be used to endorse or promote products
  17  *    derived from this software without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
  23  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  */
  31
  32 #include <sys/cdefs.h>
  33 __FBSDID("$FreeBSD$");
  34
  35 #include <sys/param.h>
  36 #include <sys/systm.h>
  37 #include <sys/kernel.h>
  38 #include <sys/conf.h>
  39 #include <sys/malloc.h>
  40 #include <sys/poll.h>
  41 #include <sys/vnode.h>
  42 #include <sys/lock.h>
  43 #include <sys/mutex.h>
  44 #include <sys/devicestat.h>
  45 #include <sys/proc.h>
  46 /* Includes to support callout */
  47 #include <sys/types.h>
  48 #include <sys/systm.h>
  49
  50 #include <cam/cam.h>
  51 #include <cam/cam_ccb.h>
  52 #include <cam/cam_periph.h>
  53 #include <cam/cam_xpt_periph.h>
  54 #include <cam/cam_sim.h>
  55 #include <cam/scsi/scsi_targetio.h>
  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_path_inq(&cpi, path);
 395         status = cpi.ccb_h.status & CAM_STATUS_MASK;
 396         if (status != CAM_REQ_CMP) {
 397                 printf("pathinq failed, status %#x\n", status);
 398                 goto enable_fail;
 399         }
 400         if ((cpi.target_sprt & PIT_PROCESSOR) == 0) {
 401                 printf("controller does not support target mode\n");
 402                 status = CAM_FUNC_NOTAVAIL;
 403                 goto enable_fail;
 404         }
 405         if (cpi.maxio == 0)
 406                 softc->maxio = DFLTPHYS;        /* traditional default */
 407         else if (cpi.maxio > maxphys)
 408                 softc->maxio = maxphys;         /* for safety */
 409         else
 410                 softc->maxio = cpi.maxio;       /* real value */
 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                 error = cam_periph_mapmem(ccb, mapinfo, softc->maxio);
 733
 734                 /*
 735                  * cam_periph_mapmem returned an error, we can't continue.
 736                  * Return the error to the user.
 737                  */
 738                 if (error) {
 739                         ccb_h->status = CAM_REQ_CMP_ERR;
 740                         mapinfo->num_bufs_used = 0;
 741                         return (error);
 742                 }
 743         }
 744
 745         /*
 746          * Once queued on the pending CCB list, this CCB will be protected
 747          * by our error recovery handler.
 748          */
 749         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("sendccb %p\n", ccb));
 750         if (XPT_FC_IS_QUEUED(ccb)) {
 751                 TAILQ_INSERT_TAIL(&softc->pending_ccb_queue, ccb_h,
 752                                   periph_links.tqe);
 753         }
 754         xpt_action(ccb);
 755
 756         return (0);
 757 }
 758
 759 /* Completion routine for CCBs (called at splsoftcam) */
 760 static void
 761 targdone(struct cam_periph *periph, union ccb *done_ccb)
 762 {
 763         struct targ_softc *softc;
 764         cam_status status;
 765
 766         CAM_DEBUG(periph->path, CAM_DEBUG_PERIPH, ("targdone %p\n", done_ccb));
 767         softc = (struct targ_softc *)periph->softc;
 768         TAILQ_REMOVE(&softc->pending_ccb_queue, &done_ccb->ccb_h,
 769                      periph_links.tqe);
 770         status = done_ccb->ccb_h.status & CAM_STATUS_MASK;
 771
 772         /* If we're no longer enabled, throw away CCB */
 773         if ((softc->state & TARG_STATE_LUN_ENABLED) == 0) {
 774                 targfreeccb(softc, done_ccb);
 775                 return;
 776         }
 777         /* abort_all_pending() waits for pending queue to be empty */
 778         if (TAILQ_EMPTY(&softc->pending_ccb_queue))
 779                 wakeup(&softc->pending_ccb_queue);
 780
 781         switch (done_ccb->ccb_h.func_code) {
 782         /* All FC_*_QUEUED CCBs go back to userland */
 783         case XPT_IMMED_NOTIFY:
 784         case XPT_IMMEDIATE_NOTIFY:
 785         case XPT_ACCEPT_TARGET_IO:
 786         case XPT_CONT_TARGET_IO:
 787                 TAILQ_INSERT_TAIL(&softc->user_ccb_queue, &done_ccb->ccb_h,
 788                                   periph_links.tqe);
 789                 cam_periph_unlock(softc->periph);
 790                 notify_user(softc);
 791                 cam_periph_lock(softc->periph);
 792                 break;
 793         default:
 794                 panic("targdone: impossible xpt opcode %#x",
 795                       done_ccb->ccb_h.func_code);
 796                 /* NOTREACHED */
 797         }
 798 }
 799
 800 /* Return CCBs to the user from the user queue and abort queue */
 801 static int
 802 targread(struct cdev *dev, struct uio *uio, int ioflag)
 803 {
 804         struct descr_queue      *abort_queue;
 805         struct targ_cmd_descr   *user_descr;
 806         struct targ_softc       *softc;
 807         struct ccb_queue  *user_queue;
 808         struct ccb_hdr    *ccb_h;
 809         union  ccb        *user_ccb;
 810         int                read_len, error;
 811
 812         error = 0;
 813         read_len = 0;
 814         devfs_get_cdevpriv((void **)&softc);
 815         user_queue = &softc->user_ccb_queue;
 816         abort_queue = &softc->abort_queue;
 817         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targread\n"));
 818
 819         /* If no data is available, wait or return immediately */
 820         cam_periph_lock(softc->periph);
 821         ccb_h = TAILQ_FIRST(user_queue);
 822         user_descr = TAILQ_FIRST(abort_queue);
 823         while (ccb_h == NULL && user_descr == NULL) {
 824                 if ((ioflag & IO_NDELAY) == 0) {
 825                         error = cam_periph_sleep(softc->periph, user_queue,
 826                             PRIBIO | PCATCH, "targrd", 0);
 827                         ccb_h = TAILQ_FIRST(user_queue);
 828                         user_descr = TAILQ_FIRST(abort_queue);
 829                         if (error != 0) {
 830                                 if (error == ERESTART) {
 831                                         continue;
 832                                 } else {
 833                                         goto read_fail;
 834                                 }
 835                         }
 836                 } else {
 837                         cam_periph_unlock(softc->periph);
 838                         return (EAGAIN);
 839                 }
 840         }
 841
 842         /* Data is available so fill the user's buffer */
 843         while (ccb_h != NULL) {
 844                 struct targ_cmd_descr *descr;
 845
 846                 if (uio->uio_resid < sizeof(user_ccb))
 847                         break;
 848                 TAILQ_REMOVE(user_queue, ccb_h, periph_links.tqe);
 849                 descr = (struct targ_cmd_descr *)ccb_h->targ_descr;
 850                 user_ccb = descr->user_ccb;
 851                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 852                           ("targread ccb %p (%p)\n", ccb_h, user_ccb));
 853                 error = targreturnccb(softc, (union ccb *)ccb_h);
 854                 if (error != 0)
 855                         goto read_fail;
 856                 cam_periph_unlock(softc->periph);
 857                 error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
 858                 cam_periph_lock(softc->periph);
 859                 if (error != 0)
 860                         goto read_fail;
 861                 read_len += sizeof(user_ccb);
 862
 863                 ccb_h = TAILQ_FIRST(user_queue);
 864         }
 865
 866         /* Flush out any aborted descriptors */
 867         while (user_descr != NULL) {
 868                 if (uio->uio_resid < sizeof(user_ccb))
 869                         break;
 870                 TAILQ_REMOVE(abort_queue, user_descr, tqe);
 871                 user_ccb = user_descr->user_ccb;
 872                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 873                           ("targread aborted descr %p (%p)\n",
 874                           user_descr, user_ccb));
 875                 suword(&user_ccb->ccb_h.status, CAM_REQ_ABORTED);
 876                 cam_periph_unlock(softc->periph);
 877                 error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
 878                 cam_periph_lock(softc->periph);
 879                 if (error != 0)
 880                         goto read_fail;
 881                 read_len += sizeof(user_ccb);
 882
 883                 user_descr = TAILQ_FIRST(abort_queue);
 884         }
 885
 886         /*
 887          * If we've successfully read some amount of data, don't report an
 888          * error.  If the error is persistent, it will be reported on the
 889          * next read().
 890          */
 891         if (read_len == 0 && uio->uio_resid != 0)
 892                 error = ENOSPC;
 893
 894 read_fail:
 895         cam_periph_unlock(softc->periph);
 896         return (error);
 897 }
 898
 899 /* Copy completed ccb back to the user */
 900 static int
 901 targreturnccb(struct targ_softc *softc, union ccb *ccb)
 902 {
 903         struct targ_cmd_descr *descr;
 904         struct ccb_hdr *u_ccbh;
 905         size_t ccb_len;
 906         int error;
 907
 908         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targreturnccb %p\n", ccb));
 909         descr = (struct targ_cmd_descr *)ccb->ccb_h.targ_descr;
 910         u_ccbh = &descr->user_ccb->ccb_h;
 911
 912         /* Copy out the central portion of the ccb_hdr */
 913         copyout(&ccb->ccb_h.retry_count, &u_ccbh->retry_count,
 914                 offsetof(struct ccb_hdr, periph_priv) -
 915                 offsetof(struct ccb_hdr, retry_count));
 916
 917         /* Copy out the rest of the ccb (after the ccb_hdr) */
 918         ccb_len = targccblen(ccb->ccb_h.func_code) - sizeof(struct ccb_hdr);
 919         if (descr->mapinfo.num_bufs_used != 0)
 920                 cam_periph_unmapmem(ccb, &descr->mapinfo);
 921         error = copyout(&ccb->ccb_h + 1, u_ccbh + 1, ccb_len);
 922         if (error != 0) {
 923                 xpt_print(softc->path,
 924                     "targreturnccb - CCB copyout failed (%d)\n", error);
 925         }
 926         /* Free CCB or send back to devq. */
 927         targfreeccb(softc, ccb);
 928
 929         return (error);
 930 }
 931
 932 static union ccb *
 933 targgetccb(struct targ_softc *softc, xpt_opcode type, int priority)
 934 {
 935         union ccb *ccb;
 936         int ccb_len;
 937
 938         ccb_len = targccblen(type);
 939         ccb = malloc(ccb_len, M_TARG, M_NOWAIT);
 940         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("getccb %p\n", ccb));
 941         if (ccb == NULL) {
 942                 return (ccb);
 943         }
 944         xpt_setup_ccb(&ccb->ccb_h, softc->path, priority);
 945         ccb->ccb_h.func_code = type;
 946         ccb->ccb_h.cbfcnp = targdone;
 947         ccb->ccb_h.targ_descr = targgetdescr(softc);
 948         if (ccb->ccb_h.targ_descr == NULL) {
 949                 free (ccb, M_TARG);
 950                 ccb = NULL;
 951         }
 952         return (ccb);
 953 }
 954
 955 static void
 956 targfreeccb(struct targ_softc *softc, union ccb *ccb)
 957 {
 958         CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH, ("targfreeccb descr %p and\n",
 959                         ccb->ccb_h.targ_descr));
 960         free(ccb->ccb_h.targ_descr, M_TARG);
 961
 962         switch (ccb->ccb_h.func_code) {
 963         case XPT_ACCEPT_TARGET_IO:
 964         case XPT_IMMED_NOTIFY:
 965         case XPT_IMMEDIATE_NOTIFY:
 966                 CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH, ("freeing ccb %p\n", ccb));
 967                 free(ccb, M_TARG);
 968                 break;
 969         default:
 970                 /* Send back CCB if we got it from the periph */
 971                 if (XPT_FC_IS_QUEUED(ccb)) {
 972                         CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH,
 973                                         ("returning queued ccb %p\n", ccb));
 974                         xpt_release_ccb(ccb);
 975                 } else {
 976                         CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH,
 977                                         ("freeing ccb %p\n", ccb));
 978                         free(ccb, M_TARG);
 979                 }
 980                 break;
 981         }
 982 }
 983
 984 static struct targ_cmd_descr *
 985 targgetdescr(struct targ_softc *softc)
 986 {
 987         struct targ_cmd_descr *descr;
 988
 989         descr = malloc(sizeof(*descr), M_TARG,
 990                M_NOWAIT);
 991         if (descr) {
 992                 descr->mapinfo.num_bufs_used = 0;
 993         }
 994         return (descr);
 995 }
 996
 997 static void
 998 targinit(void)
 999 {
1000         struct cdev *dev;
1001
1002         /* Add symbolic link to targ0 for compatibility. */
1003         dev = make_dev(&targ_cdevsw, 0, UID_ROOT, GID_WHEEL, 0600, "targ");
1004         make_dev_alias(dev, "targ0");
1005 }
1006
1007 static void
1008 targasync(void *callback_arg, u_int32_t code, struct cam_path *path, void *arg)
1009 {
1010         /* All events are handled in usermode by INOTs */
1011         panic("targasync() called, should be an INOT instead");
1012 }
1013
1014 /* Cancel all pending requests and CCBs awaiting work. */
1015 static void
1016 abort_all_pending(struct targ_softc *softc)
1017 {
1018         struct targ_cmd_descr   *descr;
1019         struct ccb_abort         cab;
1020         struct ccb_hdr          *ccb_h;
1021
1022         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("abort_all_pending\n"));
1023
1024         /* First abort the descriptors awaiting resources */
1025         while ((descr = TAILQ_FIRST(&softc->work_queue)) != NULL) {
1026                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
1027                           ("Aborting descr from workq %p\n", descr));
1028                 TAILQ_REMOVE(&softc->work_queue, descr, tqe);
1029                 TAILQ_INSERT_TAIL(&softc->abort_queue, descr, tqe);
1030         }
1031
1032         /*
1033          * Then abort all pending CCBs.
1034          * targdone() will return the aborted CCB via user_ccb_queue
1035          */
1036         xpt_setup_ccb(&cab.ccb_h, softc->path, CAM_PRIORITY_NORMAL);
1037         cab.ccb_h.func_code = XPT_ABORT;
1038         cab.ccb_h.status = CAM_REQ_CMP_ERR;
1039         TAILQ_FOREACH(ccb_h, &softc->pending_ccb_queue, periph_links.tqe) {
1040                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
1041                           ("Aborting pending CCB %p\n", ccb_h));
1042                 cab.abort_ccb = (union ccb *)ccb_h;
1043                 xpt_action((union ccb *)&cab);
1044                 if (cab.ccb_h.status != CAM_REQ_CMP) {
1045                         xpt_print(cab.ccb_h.path,
1046                             "Unable to abort CCB, status %#x\n",
1047                             cab.ccb_h.status);
1048                 }
1049         }
1050
1051         /* If we aborted at least one pending CCB ok, wait for it. */
1052         if (cab.ccb_h.status == CAM_REQ_CMP) {
1053                 cam_periph_sleep(softc->periph, &softc->pending_ccb_queue,
1054                        PRIBIO | PCATCH, "tgabrt", 0);
1055         }
1056
1057         /* If we aborted anything from the work queue, wakeup user. */
1058         if (!TAILQ_EMPTY(&softc->user_ccb_queue)
1059          || !TAILQ_EMPTY(&softc->abort_queue)) {
1060                 cam_periph_unlock(softc->periph);
1061                 notify_user(softc);
1062                 cam_periph_lock(softc->periph);
1063         }
1064 }
1065
1066 /* Notify the user that data is ready */
1067 static void
1068 notify_user(struct targ_softc *softc)
1069 {
1070         /*
1071          * Notify users sleeping via poll(), kqueue(), and
1072          * blocking read().
1073          */
1074         selwakeuppri(&softc->read_select, PRIBIO);
1075         KNOTE_UNLOCKED(&softc->read_select.si_note, 0);
1076         wakeup(&softc->user_ccb_queue);
1077 }
1078
1079 /* Convert CAM status to errno values */
1080 static int
1081 targcamstatus(cam_status status)
1082 {
1083         switch (status & CAM_STATUS_MASK) {
1084         case CAM_REQ_CMP:       /* CCB request completed without error */
1085                 return (0);
1086         case CAM_REQ_INPROG:    /* CCB request is in progress */
1087                 return (EINPROGRESS);
1088         case CAM_REQ_CMP_ERR:   /* CCB request completed with an error */
1089                 return (EIO);
1090         case CAM_PROVIDE_FAIL:  /* Unable to provide requested capability */
1091                 return (ENOTTY);
1092         case CAM_FUNC_NOTAVAIL: /* The requested function is not available */
1093                 return (ENOTSUP);
1094         case CAM_LUN_ALRDY_ENA: /* LUN is already enabled for target mode */
1095                 return (EADDRINUSE);
1096         case CAM_PATH_INVALID:  /* Supplied Path ID is invalid */
1097         case CAM_DEV_NOT_THERE: /* SCSI Device Not Installed/there */
1098                 return (ENOENT);
1099         case CAM_REQ_ABORTED:   /* CCB request aborted by the host */
1100                 return (ECANCELED);
1101         case CAM_CMD_TIMEOUT:   /* Command timeout */
1102                 return (ETIMEDOUT);
1103         case CAM_REQUEUE_REQ:   /* Requeue to preserve transaction ordering */
1104                 return (EAGAIN);
1105         case CAM_REQ_INVALID:   /* CCB request was invalid */
1106                 return (EINVAL);
1107         case CAM_RESRC_UNAVAIL: /* Resource Unavailable */
1108                 return (ENOMEM);
1109         case CAM_BUSY:          /* CAM subsystem is busy */
1110         case CAM_UA_ABORT:      /* Unable to abort CCB request */
1111                 return (EBUSY);
1112         default:
1113                 return (ENXIO);
1114         }
1115 }
1116
1117 static size_t
1118 targccblen(xpt_opcode func_code)
1119 {
1120         int len;
1121
1122         /* Codes we expect to see as a target */
1123         switch (func_code) {
1124         case XPT_CONT_TARGET_IO:
1125         case XPT_SCSI_IO:
1126                 len = sizeof(struct ccb_scsiio);
1127                 break;
1128         case XPT_ACCEPT_TARGET_IO:
1129                 len = sizeof(struct ccb_accept_tio);
1130                 break;
1131         case XPT_IMMED_NOTIFY:
1132                 len = sizeof(struct ccb_immed_notify);
1133                 break;
1134         case XPT_IMMEDIATE_NOTIFY:
1135                 len = sizeof(struct ccb_immediate_notify);
1136                 break;
1137         case XPT_REL_SIMQ:
1138                 len = sizeof(struct ccb_relsim);
1139                 break;
1140         case XPT_PATH_INQ:
1141                 len = sizeof(struct ccb_pathinq);
1142                 break;
1143         case XPT_DEBUG:
1144                 len = sizeof(struct ccb_debug);
1145                 break;
1146         case XPT_ABORT:
1147                 len = sizeof(struct ccb_abort);
1148                 break;
1149         case XPT_EN_LUN:
1150                 len = sizeof(struct ccb_en_lun);
1151                 break;
1152         default:
1153                 len = sizeof(union ccb);
1154                 break;
1155         }
1156
1157         return (len);
1158 }