sys/bus/cam/scsi/scsi_target.c

   1 /*
   2  * Generic SCSI Target Kernel Mode Driver
   3  *
   4  * Copyright (c) 2002 Nate Lawson.
   5  * Copyright (c) 1998, 1999, 2001, 2002 Justin T. Gibbs.
   6  * All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions, and the following disclaimer,
  13  *    without modification, immediately at the beginning of the file.
  14  * 2. The name of the author may not be used to endorse or promote products
  15  *    derived from this software without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
  21  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  * $FreeBSD: src/sys/cam/scsi/scsi_target.c,v 1.22.2.7 2003/02/18 22:07:10 njl Exp $
  30  * $DragonFly: src/sys/bus/cam/scsi/scsi_target.c,v 1.3 2003/07/19 21:14:15 dillon Exp $
  31  */
  32
  33 #include <sys/param.h>
  34 #include <sys/systm.h>
  35 #include <sys/kernel.h>
  36 #include <sys/conf.h>
  37 #include <sys/malloc.h>
  38 #include <sys/poll.h>
  39 #include <sys/vnode.h>
  40 #include <sys/devicestat.h>
  41
  42 #include <cam/cam.h>
  43 #include <cam/cam_ccb.h>
  44 #include <cam/cam_periph.h>
  45 #include <cam/cam_xpt_periph.h>
  46 #include <cam/scsi/scsi_targetio.h>
  47
  48 /* Transaction information attached to each CCB sent by the user */
  49 struct targ_cmd_descr {
  50         struct cam_periph_map_info  mapinfo;
  51         TAILQ_ENTRY(targ_cmd_descr) tqe;
  52         union ccb *user_ccb;
  53         int        priority;
  54         int        func_code;
  55 };
  56
  57 /* Offset into the private CCB area for storing our descriptor */
  58 #define targ_descr      periph_priv.entries[1].ptr
  59
  60 TAILQ_HEAD(descr_queue, targ_cmd_descr);
  61
  62 typedef enum {
  63         TARG_STATE_RESV         = 0x00, /* Invalid state */
  64         TARG_STATE_OPENED       = 0x01, /* Device opened, softc initialized */
  65         TARG_STATE_LUN_ENABLED  = 0x02  /* Device enabled for a path */
  66 } targ_state;
  67
  68 /* Per-instance device software context */
  69 struct targ_softc {
  70         /* CCBs (CTIOs, ATIOs, INOTs) pending on the controller */
  71         struct ccb_queue         pending_ccb_queue;
  72
  73         /* Command descriptors awaiting CTIO resources from the XPT */
  74         struct descr_queue       work_queue;
  75
  76         /* Command descriptors that have been aborted back to the user. */
  77         struct descr_queue       abort_queue;
  78
  79         /*
  80          * Queue of CCBs that have been copied out to userland, but our
  81          * userland daemon has not yet seen.
  82          */
  83         struct ccb_queue         user_ccb_queue;
  84
  85         struct cam_periph       *periph;
  86         struct cam_path         *path;
  87         targ_state               state;
  88         struct selinfo           read_select;
  89         struct devstat           device_stats;
  90 };
  91
  92 static d_open_t         targopen;
  93 static d_close_t        targclose;
  94 static d_read_t         targread;
  95 static d_write_t        targwrite;
  96 static d_ioctl_t        targioctl;
  97 static d_poll_t         targpoll;
  98 static d_kqfilter_t     targkqfilter;
  99 static void             targreadfiltdetach(struct knote *kn);
 100 static int              targreadfilt(struct knote *kn, long hint);
 101 static struct filterops targread_filtops =
 102         { 1, NULL, targreadfiltdetach, targreadfilt };
 103
 104 #define TARG_CDEV_MAJOR 65
 105 static struct cdevsw targ_cdevsw = {
 106         /* open */      targopen,
 107         /* close */     targclose,
 108         /* read */      targread,
 109         /* write */     targwrite,
 110         /* ioctl */     targioctl,
 111         /* poll */      targpoll,
 112         /* mmap */      nommap,
 113         /* strategy */  nostrategy,
 114         /* name */      "targ",
 115         /* maj */       TARG_CDEV_MAJOR,
 116         /* dump */      nodump,
 117         /* psize */     nopsize,
 118         /* flags */     D_KQFILTER,
 119         /* bmaj */      -1,
 120         /* kqfilter */  targkqfilter
 121 };
 122
 123 static cam_status       targendislun(struct cam_path *path, int enable,
 124                                      int grp6_len, int grp7_len);
 125 static cam_status       targenable(struct targ_softc *softc,
 126                                    struct cam_path *path,
 127                                    int grp6_len, int grp7_len);
 128 static cam_status       targdisable(struct targ_softc *softc);
 129 static periph_ctor_t    targctor;
 130 static periph_dtor_t    targdtor;
 131 static periph_start_t   targstart;
 132 static int              targusermerge(struct targ_softc *softc,
 133                                       struct targ_cmd_descr *descr,
 134                                       union ccb *ccb);
 135 static int              targsendccb(struct targ_softc *softc, union ccb *ccb,
 136                                     struct targ_cmd_descr *descr);
 137 static void             targdone(struct cam_periph *periph,
 138                                  union  ccb *done_ccb);
 139 static int              targreturnccb(struct targ_softc *softc,
 140                                       union  ccb *ccb);
 141 static union ccb *      targgetccb(struct targ_softc *softc, xpt_opcode type,
 142                                    int priority);
 143 static void             targfreeccb(struct targ_softc *softc, union ccb *ccb);
 144 static struct targ_cmd_descr *
 145                         targgetdescr(struct targ_softc *softc);
 146 static periph_init_t    targinit;
 147 static void             targasync(void *callback_arg, u_int32_t code,
 148                                   struct cam_path *path, void *arg);
 149 static void             abort_all_pending(struct targ_softc *softc);
 150 static void             notify_user(struct targ_softc *softc);
 151 static int              targcamstatus(cam_status status);
 152 static size_t           targccblen(xpt_opcode func_code);
 153
 154 static struct periph_driver targdriver =
 155 {
 156         targinit, "targ",
 157         TAILQ_HEAD_INITIALIZER(targdriver.units), /* generation */ 0
 158 };
 159 DATA_SET(periphdriver_set, targdriver);
 160
 161 static MALLOC_DEFINE(M_TARG, "TARG", "TARG data");
 162
 163 /* Create softc and initialize it. Only one proc can open each targ device. */
 164 static int
 165 targopen(dev_t dev, int flags, int fmt, struct proc *p)
 166 {
 167         struct targ_softc *softc;
 168
 169         if (dev->si_drv1 != 0) {
 170                 return (EBUSY);
 171         }
 172
 173         /* Mark device busy before any potentially blocking operations */
 174         dev->si_drv1 = (void *)~0;
 175
 176         /* Create the targ device, allocate its softc, initialize it */
 177         make_dev(&targ_cdevsw, minor(dev), UID_ROOT, GID_WHEEL, 0600,
 178                          "targ%d", lminor(dev));
 179         MALLOC(softc, struct targ_softc *, sizeof(*softc), M_TARG,
 180                M_WAITOK | M_ZERO);
 181         dev->si_drv1 = softc;
 182         softc->state = TARG_STATE_OPENED;
 183         softc->periph = NULL;
 184         softc->path = NULL;
 185
 186         TAILQ_INIT(&softc->pending_ccb_queue);
 187         TAILQ_INIT(&softc->work_queue);
 188         TAILQ_INIT(&softc->abort_queue);
 189         TAILQ_INIT(&softc->user_ccb_queue);
 190
 191         return (0);
 192 }
 193
 194 /* Disable LUN if enabled and teardown softc */
 195 static int
 196 targclose(dev_t dev, int flag, int fmt, struct proc *p)
 197 {
 198         struct targ_softc     *softc;
 199         int    error;
 200
 201         softc = (struct targ_softc *)dev->si_drv1;
 202         error = targdisable(softc);
 203         if (error == CAM_REQ_CMP) {
 204                 dev->si_drv1 = 0;
 205                 if (softc->periph != NULL) {
 206                         cam_periph_invalidate(softc->periph);
 207                         softc->periph = NULL;
 208                 }
 209                 destroy_dev(dev);
 210                 FREE(softc, M_TARG);
 211         }
 212         return (error);
 213 }
 214
 215 /* Enable/disable LUNs, set debugging level */
 216 static int
 217 targioctl(dev_t dev, u_long cmd, caddr_t addr, int flag, struct proc *p)
 218 {
 219         struct targ_softc *softc;
 220         cam_status         status;
 221
 222         softc = (struct targ_softc *)dev->si_drv1;
 223
 224         switch (cmd) {
 225         case TARGIOCENABLE:
 226         {
 227                 struct ioc_enable_lun   *new_lun;
 228                 struct cam_path         *path;
 229
 230                 new_lun = (struct ioc_enable_lun *)addr;
 231                 status = xpt_create_path(&path, /*periph*/NULL,
 232                                          new_lun->path_id,
 233                                          new_lun->target_id,
 234                                          new_lun->lun_id);
 235                 if (status != CAM_REQ_CMP) {
 236                         printf("Couldn't create path, status %#x\n", status);
 237                         break;
 238                 }
 239                 status = targenable(softc, path, new_lun->grp6_len,
 240                                     new_lun->grp7_len);
 241                 xpt_free_path(path);
 242                 break;
 243         }
 244         case TARGIOCDISABLE:
 245                 status = targdisable(softc);
 246                 break;
 247         case TARGIOCDEBUG:
 248         {
 249 #ifdef  CAMDEBUG
 250                 struct ccb_debug cdbg;
 251
 252                 bzero(&cdbg, sizeof cdbg);
 253                 if (*((int *)addr) != 0)
 254                         cdbg.flags = CAM_DEBUG_PERIPH;
 255                 else
 256                         cdbg.flags = CAM_DEBUG_NONE;
 257                 xpt_setup_ccb(&cdbg.ccb_h, softc->path, /*priority*/0);
 258                 cdbg.ccb_h.func_code = XPT_DEBUG;
 259                 cdbg.ccb_h.cbfcnp = targdone;
 260
 261                 /* If no periph available, disallow debugging changes */
 262                 if ((softc->state & TARG_STATE_LUN_ENABLED) == 0) {
 263                         status = CAM_DEV_NOT_THERE;
 264                         break;
 265                 }
 266                 xpt_action((union ccb *)&cdbg);
 267                 status = cdbg.ccb_h.status & CAM_STATUS_MASK;
 268 #else
 269                 status = CAM_FUNC_NOTAVAIL;
 270 #endif
 271                 break;
 272         }
 273         default:
 274                 status = CAM_PROVIDE_FAIL;
 275                 break;
 276         }
 277
 278         return (targcamstatus(status));
 279 }
 280
 281 /* Writes are always ready, reads wait for user_ccb_queue or abort_queue */
 282 static int
 283 targpoll(dev_t dev, int poll_events, struct proc *p)
 284 {
 285         struct targ_softc *softc;
 286         int     revents, s;
 287
 288         softc = (struct targ_softc *)dev->si_drv1;
 289
 290         /* Poll for write() is always ok. */
 291         revents = poll_events & (POLLOUT | POLLWRNORM);
 292         if ((poll_events & (POLLIN | POLLRDNORM)) != 0) {
 293                 s = splsoftcam();
 294                 /* Poll for read() depends on user and abort queues. */
 295                 if (!TAILQ_EMPTY(&softc->user_ccb_queue) ||
 296                     !TAILQ_EMPTY(&softc->abort_queue)) {
 297                         revents |= poll_events & (POLLIN | POLLRDNORM);
 298                 }
 299                 /* Only sleep if the user didn't poll for write. */
 300                 if (revents == 0)
 301                         selrecord(p, &softc->read_select);
 302                 splx(s);
 303         }
 304
 305         return (revents);
 306 }
 307
 308 static int
 309 targkqfilter(dev_t dev, struct knote *kn)
 310 {
 311         struct  targ_softc *softc;
 312         int     s;
 313
 314         softc = (struct targ_softc *)dev->si_drv1;
 315         kn->kn_hook = (caddr_t)softc;
 316         kn->kn_fop = &targread_filtops;
 317         s = splsoftcam();
 318         SLIST_INSERT_HEAD(&softc->read_select.si_note, kn, kn_selnext);
 319         splx(s);
 320         return (0);
 321 }
 322
 323 static void
 324 targreadfiltdetach(struct knote *kn)
 325 {
 326         struct  targ_softc *softc;
 327         int     s;
 328
 329         softc = (struct targ_softc *)kn->kn_hook;
 330         s = splsoftcam();
 331         SLIST_REMOVE(&softc->read_select.si_note, kn, knote, kn_selnext);
 332         splx(s);
 333 }
 334
 335 /* Notify the user's kqueue when the user queue or abort queue gets a CCB */
 336 static int
 337 targreadfilt(struct knote *kn, long hint)
 338 {
 339         struct targ_softc *softc;
 340         int     retval, s;
 341
 342         softc = (struct targ_softc *)kn->kn_hook;
 343         s = splsoftcam();
 344         retval = !TAILQ_EMPTY(&softc->user_ccb_queue) ||
 345                  !TAILQ_EMPTY(&softc->abort_queue);
 346         splx(s);
 347         return (retval);
 348 }
 349
 350 /* Send the HBA the enable/disable message */
 351 static cam_status
 352 targendislun(struct cam_path *path, int enable, int grp6_len, int grp7_len)
 353 {
 354         struct ccb_en_lun en_ccb;
 355         cam_status        status;
 356
 357         /* Tell the lun to begin answering selects */
 358         xpt_setup_ccb(&en_ccb.ccb_h, path, /*priority*/1);
 359         en_ccb.ccb_h.func_code = XPT_EN_LUN;
 360         /* Don't need support for any vendor specific commands */
 361         en_ccb.grp6_len = grp6_len;
 362         en_ccb.grp7_len = grp7_len;
 363         en_ccb.enable = enable ? 1 : 0;
 364         xpt_action((union ccb *)&en_ccb);
 365         status = en_ccb.ccb_h.status & CAM_STATUS_MASK;
 366         if (status != CAM_REQ_CMP) {
 367                 xpt_print_path(path);
 368                 printf("%sable lun CCB rejected, status %#x\n",
 369                        enable ? "en" : "dis", status);
 370         }
 371         return (status);
 372 }
 373
 374 /* Enable target mode on a LUN, given its path */
 375 static cam_status
 376 targenable(struct targ_softc *softc, struct cam_path *path, int grp6_len,
 377            int grp7_len)
 378 {
 379         struct cam_periph *periph;
 380         struct ccb_pathinq cpi;
 381         cam_status         status;
 382
 383         if ((softc->state & TARG_STATE_LUN_ENABLED) != 0)
 384                 return (CAM_LUN_ALRDY_ENA);
 385
 386         /* Make sure SIM supports target mode */
 387         xpt_setup_ccb(&cpi.ccb_h, path, /*priority*/1);
 388         cpi.ccb_h.func_code = XPT_PATH_INQ;
 389         xpt_action((union ccb *)&cpi);
 390         status = cpi.ccb_h.status & CAM_STATUS_MASK;
 391         if (status != CAM_REQ_CMP) {
 392                 printf("pathinq failed, status %#x\n", status);
 393                 goto enable_fail;
 394         }
 395         if ((cpi.target_sprt & PIT_PROCESSOR) == 0) {
 396                 printf("controller does not support target mode\n");
 397                 status = CAM_FUNC_NOTAVAIL;
 398                 goto enable_fail;
 399         }
 400
 401         /* Destroy any periph on our path if it is disabled */
 402         periph = cam_periph_find(path, "targ");
 403         if (periph != NULL) {
 404                 struct targ_softc *del_softc;
 405
 406                 del_softc = (struct targ_softc *)periph->softc;
 407                 if ((del_softc->state & TARG_STATE_LUN_ENABLED) == 0) {
 408                         cam_periph_invalidate(del_softc->periph);
 409                         del_softc->periph = NULL;
 410                 } else {
 411                         printf("Requested path still in use by targ%d\n",
 412                                periph->unit_number);
 413                         status = CAM_LUN_ALRDY_ENA;
 414                         goto enable_fail;
 415                 }
 416         }
 417
 418         /* Create a periph instance attached to this path */
 419         status = cam_periph_alloc(targctor, NULL, targdtor, targstart,
 420                         "targ", CAM_PERIPH_BIO, path, targasync, 0, softc);
 421         if (status != CAM_REQ_CMP) {
 422                 printf("cam_periph_alloc failed, status %#x\n", status);
 423                 goto enable_fail;
 424         }
 425
 426         /* Ensure that the periph now exists. */
 427         if (cam_periph_find(path, "targ") == NULL) {
 428                 panic("targenable: succeeded but no periph?");
 429                 /* NOTREACHED */
 430         }
 431
 432         /* Send the enable lun message */
 433         status = targendislun(path, /*enable*/1, grp6_len, grp7_len);
 434         if (status != CAM_REQ_CMP) {
 435                 printf("enable lun failed, status %#x\n", status);
 436                 goto enable_fail;
 437         }
 438         softc->state |= TARG_STATE_LUN_ENABLED;
 439
 440 enable_fail:
 441         return (status);
 442 }
 443
 444 /* Disable this softc's target instance if enabled */
 445 static cam_status
 446 targdisable(struct targ_softc *softc)
 447 {
 448         cam_status status;
 449         int s;
 450
 451         if ((softc->state & TARG_STATE_LUN_ENABLED) == 0)
 452                 return (CAM_REQ_CMP);
 453
 454         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targdisable\n"));
 455
 456         /* Abort any ccbs pending on the controller */
 457         s = splcam();
 458         abort_all_pending(softc);
 459         splx(s);
 460
 461         /* Disable this lun */
 462         status = targendislun(softc->path, /*enable*/0,
 463                               /*grp6_len*/0, /*grp7_len*/0);
 464         if (status == CAM_REQ_CMP)
 465                 softc->state &= ~TARG_STATE_LUN_ENABLED;
 466         else
 467                 printf("Disable lun failed, status %#x\n", status);
 468
 469         return (status);
 470 }
 471
 472 /* Initialize a periph (called from cam_periph_alloc) */
 473 static cam_status
 474 targctor(struct cam_periph *periph, void *arg)
 475 {
 476         struct targ_softc *softc;
 477
 478         /* Store pointer to softc for periph-driven routines */
 479         softc = (struct targ_softc *)arg;
 480         periph->softc = softc;
 481         softc->periph = periph;
 482         softc->path = periph->path;
 483         return (CAM_REQ_CMP);
 484 }
 485
 486 static void
 487 targdtor(struct cam_periph *periph)
 488 {
 489         struct targ_softc     *softc;
 490         struct ccb_hdr        *ccb_h;
 491         struct targ_cmd_descr *descr;
 492
 493         softc = (struct targ_softc *)periph->softc;
 494
 495         /*
 496          * targdisable() aborts CCBs back to the user and leaves them
 497          * on user_ccb_queue and abort_queue in case the user is still
 498          * interested in them.  We free them now.
 499          */
 500         while ((ccb_h = TAILQ_FIRST(&softc->user_ccb_queue)) != NULL) {
 501                 TAILQ_REMOVE(&softc->user_ccb_queue, ccb_h, periph_links.tqe);
 502                 targfreeccb(softc, (union ccb *)ccb_h);
 503         }
 504         while ((descr = TAILQ_FIRST(&softc->abort_queue)) != NULL) {
 505                 TAILQ_REMOVE(&softc->abort_queue, descr, tqe);
 506                 FREE(descr, M_TARG);
 507         }
 508
 509         softc->periph = NULL;
 510         softc->path = NULL;
 511         periph->softc = NULL;
 512 }
 513
 514 /* Receive CCBs from user mode proc and send them to the HBA */
 515 static int
 516 targwrite(dev_t dev, struct uio *uio, int ioflag)
 517 {
 518         union ccb *user_ccb;
 519         struct targ_softc *softc;
 520         struct targ_cmd_descr *descr;
 521         int write_len, error, s;
 522         int func_code, priority;
 523
 524         softc = (struct targ_softc *)dev->si_drv1;
 525         write_len = error = 0;
 526         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 527                   ("write - uio_resid %d\n", uio->uio_resid));
 528         while (uio->uio_resid >= sizeof(user_ccb) && error == 0) {
 529                 union ccb *ccb;
 530                 int error;
 531
 532                 error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
 533                 if (error != 0) {
 534                         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 535                                   ("write - uiomove failed (%d)\n", error));
 536                         break;
 537                 }
 538                 priority = fuword(&user_ccb->ccb_h.pinfo.priority);
 539                 if (priority == -1) {
 540                         error = EINVAL;
 541                         break;
 542                 }
 543                 func_code = fuword(&user_ccb->ccb_h.func_code);
 544                 switch (func_code) {
 545                 case XPT_ACCEPT_TARGET_IO:
 546                 case XPT_IMMED_NOTIFY:
 547                         ccb = targgetccb(softc, func_code, priority);
 548                         descr = (struct targ_cmd_descr *)ccb->ccb_h.targ_descr;
 549                         descr->user_ccb = user_ccb;
 550                         descr->func_code = func_code;
 551                         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 552                                   ("Sent ATIO/INOT (%p)\n", user_ccb));
 553                         xpt_action(ccb);
 554                         s = splsoftcam();
 555                         TAILQ_INSERT_TAIL(&softc->pending_ccb_queue,
 556                                           &ccb->ccb_h,
 557                                           periph_links.tqe);
 558                         splx(s);
 559                         break;
 560                 default:
 561                         if ((func_code & XPT_FC_QUEUED) != 0) {
 562                                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 563                                           ("Sending queued ccb %#x (%p)\n",
 564                                           func_code, user_ccb));
 565                                 descr = targgetdescr(softc);
 566                                 descr->user_ccb = user_ccb;
 567                                 descr->priority = priority;
 568                                 descr->func_code = func_code;
 569                                 s = splsoftcam();
 570                                 TAILQ_INSERT_TAIL(&softc->work_queue,
 571                                                   descr, tqe);
 572                                 splx(s);
 573                                 xpt_schedule(softc->periph, priority);
 574                         } else {
 575                                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 576                                           ("Sending inline ccb %#x (%p)\n",
 577                                           func_code, user_ccb));
 578                                 ccb = targgetccb(softc, func_code, priority);
 579                                 descr = (struct targ_cmd_descr *)
 580                                          ccb->ccb_h.targ_descr;
 581                                 descr->user_ccb = user_ccb;
 582                                 descr->priority = priority;
 583                                 descr->func_code = func_code;
 584                                 if (targusermerge(softc, descr, ccb) != EFAULT)
 585                                         targsendccb(softc, ccb, descr);
 586                                 targreturnccb(softc, ccb);
 587                         }
 588                         break;
 589                 }
 590                 write_len += sizeof(user_ccb);
 591         }
 592
 593         /*
 594          * If we've successfully taken in some amount of
 595          * data, return success for that data first.  If
 596          * an error is persistent, it will be reported
 597          * on the next write.
 598          */
 599         if (error != 0 && write_len == 0)
 600                 return (error);
 601         if (write_len == 0 && uio->uio_resid != 0)
 602                 return (ENOSPC);
 603         return (0);
 604 }
 605
 606 /* Process requests (descrs) via the periph-supplied CCBs */
 607 static void
 608 targstart(struct cam_periph *periph, union ccb *start_ccb)
 609 {
 610         struct targ_softc *softc;
 611         struct targ_cmd_descr *descr, *next_descr;
 612         int s, error;
 613
 614         softc = (struct targ_softc *)periph->softc;
 615         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targstart %p\n", start_ccb));
 616
 617         s = splsoftcam();
 618         descr = TAILQ_FIRST(&softc->work_queue);
 619         if (descr == NULL) {
 620                 splx(s);
 621                 xpt_release_ccb(start_ccb);
 622         } else {
 623                 TAILQ_REMOVE(&softc->work_queue, descr, tqe);
 624                 next_descr = TAILQ_FIRST(&softc->work_queue);
 625                 splx(s);
 626
 627                 /* Initiate a transaction using the descr and supplied CCB */
 628                 error = targusermerge(softc, descr, start_ccb);
 629                 if (error == 0)
 630                         error = targsendccb(softc, start_ccb, descr);
 631                 if (error != 0) {
 632                         xpt_print_path(periph->path);
 633                         printf("targsendccb failed, err %d\n", error);
 634                         xpt_release_ccb(start_ccb);
 635                         suword(&descr->user_ccb->ccb_h.status,
 636                                CAM_REQ_CMP_ERR);
 637                         s = splsoftcam();
 638                         TAILQ_INSERT_TAIL(&softc->abort_queue, descr, tqe);
 639                         splx(s);
 640                         notify_user(softc);
 641                 }
 642
 643                 /* If we have more work to do, stay scheduled */
 644                 if (next_descr != NULL)
 645                         xpt_schedule(periph, next_descr->priority);
 646         }
 647 }
 648
 649 static int
 650 targusermerge(struct targ_softc *softc, struct targ_cmd_descr *descr,
 651               union ccb *ccb)
 652 {
 653         struct ccb_hdr *u_ccbh, *k_ccbh;
 654         size_t ccb_len;
 655         int error;
 656
 657         u_ccbh = &descr->user_ccb->ccb_h;
 658         k_ccbh = &ccb->ccb_h;
 659
 660         /*
 661          * There are some fields in the CCB header that need to be
 662          * preserved, the rest we get from the user ccb. (See xpt_merge_ccb)
 663          */
 664         xpt_setup_ccb(k_ccbh, softc->path, descr->priority);
 665         k_ccbh->retry_count = fuword(&u_ccbh->retry_count);
 666         k_ccbh->func_code = descr->func_code;
 667         k_ccbh->flags = fuword(&u_ccbh->flags);
 668         k_ccbh->timeout = fuword(&u_ccbh->timeout);
 669         ccb_len = targccblen(k_ccbh->func_code) - sizeof(struct ccb_hdr);
 670         error = copyin(u_ccbh + 1, k_ccbh + 1, ccb_len);
 671         if (error != 0) {
 672                 k_ccbh->status = CAM_REQ_CMP_ERR;
 673                 return (error);
 674         }
 675
 676         /* Translate usermode abort_ccb pointer to its kernel counterpart */
 677         if (k_ccbh->func_code == XPT_ABORT) {
 678                 struct ccb_abort *cab;
 679                 struct ccb_hdr *ccb_h;
 680                 int s;
 681
 682                 cab = (struct ccb_abort *)ccb;
 683                 s = splsoftcam();
 684                 TAILQ_FOREACH(ccb_h, &softc->pending_ccb_queue,
 685                     periph_links.tqe) {
 686                         struct targ_cmd_descr *ab_descr;
 687
 688                         ab_descr = (struct targ_cmd_descr *)ccb_h->targ_descr;
 689                         if (ab_descr->user_ccb == cab->abort_ccb) {
 690                                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 691                                           ("Changing abort for %p to %p\n",
 692                                           cab->abort_ccb, ccb_h));
 693                                 cab->abort_ccb = (union ccb *)ccb_h;
 694                                 break;
 695                         }
 696                 }
 697                 splx(s);
 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         /*
 731          * We only attempt to map the user memory into kernel space
 732          * if they haven't passed in a physical memory pointer,
 733          * and if there is actually an I/O operation to perform.
 734          * Right now cam_periph_mapmem() only supports SCSI and device
 735          * match CCBs.  For the SCSI CCBs, we only pass the CCB in if
 736          * there's actually data to map.  cam_periph_mapmem() will do the
 737          * right thing, even if there isn't data to map, but since CCBs
 738          * without data are a reasonably common occurance (e.g. test unit
 739          * ready), it will save a few cycles if we check for it here.
 740          */
 741         if (((ccb_h->flags & CAM_DATA_PHYS) == 0)
 742          && (((ccb_h->func_code == XPT_CONT_TARGET_IO)
 743             && ((ccb_h->flags & CAM_DIR_MASK) != CAM_DIR_NONE))
 744           || (ccb_h->func_code == XPT_DEV_MATCH))) {
 745
 746                 error = cam_periph_mapmem(ccb, mapinfo);
 747
 748                 /*
 749                  * cam_periph_mapmem returned an error, we can't continue.
 750                  * Return the error to the user.
 751                  */
 752                 if (error) {
 753                         ccb_h->status = CAM_REQ_CMP_ERR;
 754                         mapinfo->num_bufs_used = 0;
 755                         return (error);
 756                 }
 757         }
 758
 759         /*
 760          * Once queued on the pending CCB list, this CCB will be protected
 761          * by our error recovery handler.
 762          */
 763         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("sendccb %p\n", ccb));
 764         if (XPT_FC_IS_QUEUED(ccb)) {
 765                 int s;
 766
 767                 s = splsoftcam();
 768                 TAILQ_INSERT_TAIL(&softc->pending_ccb_queue, ccb_h,
 769                                   periph_links.tqe);
 770                 splx(s);
 771         }
 772         xpt_action(ccb);
 773
 774         return (0);
 775 }
 776
 777 /* Completion routine for CCBs (called at splsoftcam) */
 778 static void
 779 targdone(struct cam_periph *periph, union ccb *done_ccb)
 780 {
 781         struct targ_softc *softc;
 782         cam_status status;
 783
 784         CAM_DEBUG(periph->path, CAM_DEBUG_PERIPH, ("targdone %p\n", done_ccb));
 785         softc = (struct targ_softc *)periph->softc;
 786         TAILQ_REMOVE(&softc->pending_ccb_queue, &done_ccb->ccb_h,
 787                      periph_links.tqe);
 788         status = done_ccb->ccb_h.status & CAM_STATUS_MASK;
 789
 790         /* If we're no longer enabled, throw away CCB */
 791         if ((softc->state & TARG_STATE_LUN_ENABLED) == 0) {
 792                 targfreeccb(softc, done_ccb);
 793                 return;
 794         }
 795         /* abort_all_pending() waits for pending queue to be empty */
 796         if (TAILQ_EMPTY(&softc->pending_ccb_queue))
 797                 wakeup(&softc->pending_ccb_queue);
 798
 799         switch (done_ccb->ccb_h.func_code) {
 800         /* All FC_*_QUEUED CCBs go back to userland */
 801         case XPT_IMMED_NOTIFY:
 802         case XPT_ACCEPT_TARGET_IO:
 803         case XPT_CONT_TARGET_IO:
 804                 TAILQ_INSERT_TAIL(&softc->user_ccb_queue, &done_ccb->ccb_h,
 805                                   periph_links.tqe);
 806                 notify_user(softc);
 807                 break;
 808         default:
 809                 panic("targdone: impossible xpt opcode %#x",
 810                       done_ccb->ccb_h.func_code);
 811                 /* NOTREACHED */
 812         }
 813 }
 814
 815 /* Return CCBs to the user from the user queue and abort queue */
 816 static int
 817 targread(dev_t dev, struct uio *uio, int ioflag)
 818 {
 819         struct descr_queue      *abort_queue;
 820         struct targ_cmd_descr   *user_descr;
 821         struct targ_softc       *softc;
 822         struct ccb_queue  *user_queue;
 823         struct ccb_hdr    *ccb_h;
 824         union  ccb        *user_ccb;
 825         int                read_len, error, s;
 826
 827         error = 0;
 828         read_len = 0;
 829         softc = (struct targ_softc *)dev->si_drv1;
 830         user_queue = &softc->user_ccb_queue;
 831         abort_queue = &softc->abort_queue;
 832         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targread\n"));
 833
 834         /* If no data is available, wait or return immediately */
 835         s = splsoftcam();
 836         ccb_h = TAILQ_FIRST(user_queue);
 837         user_descr = TAILQ_FIRST(abort_queue);
 838         while (ccb_h == NULL && user_descr == NULL) {
 839                 if ((ioflag & IO_NDELAY) == 0) {
 840                         error = tsleep(user_queue, PCATCH, "targrd", 0);
 841                         ccb_h = TAILQ_FIRST(user_queue);
 842                         user_descr = TAILQ_FIRST(abort_queue);
 843                         if (error != 0) {
 844                                 if (error == ERESTART) {
 845                                         continue;
 846                                 } else {
 847                                         splx(s);
 848                                         goto read_fail;
 849                                 }
 850                         }
 851                 } else {
 852                         splx(s);
 853                         return (EAGAIN);
 854                 }
 855         }
 856
 857         /* Data is available so fill the user's buffer */
 858         while (ccb_h != NULL) {
 859                 struct targ_cmd_descr *descr;
 860
 861                 if (uio->uio_resid < sizeof(user_ccb))
 862                         break;
 863                 TAILQ_REMOVE(user_queue, ccb_h, periph_links.tqe);
 864                 splx(s);
 865                 descr = (struct targ_cmd_descr *)ccb_h->targ_descr;
 866                 user_ccb = descr->user_ccb;
 867                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 868                           ("targread ccb %p (%p)\n", ccb_h, user_ccb));
 869                 error = targreturnccb(softc, (union ccb *)ccb_h);
 870                 if (error != 0)
 871                         goto read_fail;
 872                 error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
 873                 if (error != 0)
 874                         goto read_fail;
 875                 read_len += sizeof(user_ccb);
 876
 877                 s = splsoftcam();
 878                 ccb_h = TAILQ_FIRST(user_queue);
 879         }
 880
 881         /* Flush out any aborted descriptors */
 882         while (user_descr != NULL) {
 883                 if (uio->uio_resid < sizeof(user_ccb))
 884                         break;
 885                 TAILQ_REMOVE(abort_queue, user_descr, tqe);
 886                 splx(s);
 887                 user_ccb = user_descr->user_ccb;
 888                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 889                           ("targread aborted descr %p (%p)\n",
 890                           user_descr, user_ccb));
 891                 suword(&user_ccb->ccb_h.status, CAM_REQ_ABORTED);
 892                 error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
 893                 if (error != 0)
 894                         goto read_fail;
 895                 read_len += sizeof(user_ccb);
 896
 897                 s = splsoftcam();
 898                 user_descr = TAILQ_FIRST(abort_queue);
 899         }
 900         splx(s);
 901
 902         /*
 903          * If we've successfully read some amount of data, don't report an
 904          * error.  If the error is persistent, it will be reported on the
 905          * next read().
 906          */
 907         if (read_len == 0 && uio->uio_resid != 0)
 908                 error = ENOSPC;
 909
 910 read_fail:
 911         return (error);
 912 }
 913
 914 /* Copy completed ccb back to the user */
 915 static int
 916 targreturnccb(struct targ_softc *softc, union ccb *ccb)
 917 {
 918         struct targ_cmd_descr *descr;
 919         struct ccb_hdr *u_ccbh;
 920         size_t ccb_len;
 921         int error;
 922
 923         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targreturnccb %p\n", ccb));
 924         descr = (struct targ_cmd_descr *)ccb->ccb_h.targ_descr;
 925         u_ccbh = &descr->user_ccb->ccb_h;
 926
 927         /* Copy out the central portion of the ccb_hdr */
 928         copyout(&ccb->ccb_h.retry_count, &u_ccbh->retry_count,
 929                 offsetof(struct ccb_hdr, periph_priv) -
 930                 offsetof(struct ccb_hdr, retry_count));
 931
 932         /* Copy out the rest of the ccb (after the ccb_hdr) */
 933         ccb_len = targccblen(ccb->ccb_h.func_code) - sizeof(struct ccb_hdr);
 934         if (descr->mapinfo.num_bufs_used != 0)
 935                 cam_periph_unmapmem(ccb, &descr->mapinfo);
 936         error = copyout(&ccb->ccb_h + 1, u_ccbh + 1, ccb_len);
 937         if (error != 0) {
 938                 xpt_print_path(softc->path);
 939                 printf("targreturnccb - CCB copyout failed (%d)\n",
 940                        error);
 941         }
 942         /* Free CCB or send back to devq. */
 943         targfreeccb(softc, ccb);
 944
 945         return (error);
 946 }
 947
 948 static union ccb *
 949 targgetccb(struct targ_softc *softc, xpt_opcode type, int priority)
 950 {
 951         union ccb *ccb;
 952         int ccb_len;
 953
 954         ccb_len = targccblen(type);
 955         MALLOC(ccb, union ccb *, ccb_len, M_TARG, M_WAITOK);
 956         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("getccb %p\n", ccb));
 957
 958         xpt_setup_ccb(&ccb->ccb_h, softc->path, priority);
 959         ccb->ccb_h.func_code = type;
 960         ccb->ccb_h.cbfcnp = targdone;
 961         ccb->ccb_h.targ_descr = targgetdescr(softc);
 962         return (ccb);
 963 }
 964
 965 static void
 966 targfreeccb(struct targ_softc *softc, union ccb *ccb)
 967 {
 968         CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH, ("targfreeccb descr %p and\n",
 969                         ccb->ccb_h.targ_descr));
 970         FREE(ccb->ccb_h.targ_descr, M_TARG);
 971
 972         switch (ccb->ccb_h.func_code) {
 973         case XPT_ACCEPT_TARGET_IO:
 974         case XPT_IMMED_NOTIFY:
 975                 CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH, ("freeing ccb %p\n", ccb));
 976                 FREE(ccb, M_TARG);
 977                 break;
 978         default:
 979                 /* Send back CCB if we got it from the periph */
 980                 if (XPT_FC_IS_QUEUED(ccb)) {
 981                         CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH,
 982                                         ("returning queued ccb %p\n", ccb));
 983                         xpt_release_ccb(ccb);
 984                 } else {
 985                         CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH,
 986                                         ("freeing ccb %p\n", ccb));
 987                         FREE(ccb, M_TARG);
 988                 }
 989                 break;
 990         }
 991 }
 992
 993 static struct targ_cmd_descr *
 994 targgetdescr(struct targ_softc *softc)
 995 {
 996         struct targ_cmd_descr *descr;
 997
 998         MALLOC(descr, struct targ_cmd_descr *, sizeof(*descr), M_TARG,
 999                M_WAITOK);
1000         descr->mapinfo.num_bufs_used = 0;
1001         return (descr);
1002 }
1003
1004 static void
1005 targinit(void)
1006 {
1007         cdevsw_add(&targ_cdevsw);
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, /*priority*/0);
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_path(cab.ccb_h.path);
1049                         printf("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                 tsleep(&softc->pending_ccb_queue, PCATCH, "tgabrt", 0);
1057         }
1058
1059         /* If we aborted anything from the work queue, wakeup user. */
1060         if (!TAILQ_EMPTY(&softc->user_ccb_queue)
1061          || !TAILQ_EMPTY(&softc->abort_queue))
1062                 notify_user(softc);
1063 }
1064
1065 /* Notify the user that data is ready */
1066 static void
1067 notify_user(struct targ_softc *softc)
1068 {
1069         /*
1070          * Notify users sleeping via poll(), kqueue(), and
1071          * blocking read().
1072          */
1073         selwakeup(&softc->read_select);
1074         KNOTE(&softc->read_select.si_note, 0);
1075         wakeup(&softc->user_ccb_queue);
1076 }
1077
1078 /* Convert CAM status to errno values */
1079 static int
1080 targcamstatus(cam_status status)
1081 {
1082         switch (status & CAM_STATUS_MASK) {
1083         case CAM_REQ_CMP:       /* CCB request completed without error */
1084                 return (0);
1085         case CAM_REQ_INPROG:    /* CCB request is in progress */
1086                 return (EINPROGRESS);
1087         case CAM_REQ_CMP_ERR:   /* CCB request completed with an error */
1088                 return (EIO);
1089         case CAM_PROVIDE_FAIL:  /* Unable to provide requested capability */
1090                 return (ENOTTY);
1091         case CAM_FUNC_NOTAVAIL: /* The requested function is not available */
1092                 return (ENOTSUP);
1093         case CAM_LUN_ALRDY_ENA: /* LUN is already enabled for target mode */
1094                 return (EADDRINUSE);
1095         case CAM_PATH_INVALID:  /* Supplied Path ID is invalid */
1096         case CAM_DEV_NOT_THERE: /* SCSI Device Not Installed/there */
1097                 return (ENOENT);
1098         case CAM_REQ_ABORTED:   /* CCB request aborted by the host */
1099                 return (ECANCELED);
1100         case CAM_CMD_TIMEOUT:   /* Command timeout */
1101                 return (ETIMEDOUT);
1102         case CAM_REQUEUE_REQ:   /* Requeue to preserve transaction ordering */
1103                 return (EAGAIN);
1104         case CAM_REQ_INVALID:   /* CCB request was invalid */
1105                 return (EINVAL);
1106         case CAM_RESRC_UNAVAIL: /* Resource Unavailable */
1107                 return (ENOMEM);
1108         case CAM_BUSY:          /* CAM subsytem is busy */
1109         case CAM_UA_ABORT:      /* Unable to abort CCB request */
1110                 return (EBUSY);
1111         default:
1112                 return (ENXIO);
1113         }
1114 }
1115
1116 static size_t
1117 targccblen(xpt_opcode func_code)
1118 {
1119         int len;
1120
1121         /* Codes we expect to see as a target */
1122         switch (func_code) {
1123         case XPT_CONT_TARGET_IO:
1124         case XPT_SCSI_IO:
1125                 len = sizeof(struct ccb_scsiio);
1126                 break;
1127         case XPT_ACCEPT_TARGET_IO:
1128                 len = sizeof(struct ccb_accept_tio);
1129                 break;
1130         case XPT_IMMED_NOTIFY:
1131                 len = sizeof(struct ccb_immed_notify);
1132                 break;
1133         case XPT_REL_SIMQ:
1134                 len = sizeof(struct ccb_relsim);
1135                 break;
1136         case XPT_PATH_INQ:
1137                 len = sizeof(struct ccb_pathinq);
1138                 break;
1139         case XPT_DEBUG:
1140                 len = sizeof(struct ccb_debug);
1141                 break;
1142         case XPT_ABORT:
1143                 len = sizeof(struct ccb_abort);
1144                 break;
1145         case XPT_EN_LUN:
1146                 len = sizeof(struct ccb_en_lun);
1147                 break;
1148         default:
1149                 len = sizeof(union ccb);
1150                 break;
1151         }
1152
1153         return (len);
1154 }