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 1.11 2005/06/02 20:40:31 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 #include <sys/thread2.h>
  42
  43 #include "../cam.h"
  44 #include "../cam_ccb.h"
  45 #include "../cam_periph.h"
  46 #include "../cam_xpt_periph.h"
  47 #include "scsi_targetio.h"
  48
  49 /* Transaction information attached to each CCB sent by the user */
  50 struct targ_cmd_descr {
  51         struct cam_periph_map_info  mapinfo;
  52         TAILQ_ENTRY(targ_cmd_descr) tqe;
  53         union ccb *user_ccb;
  54         int        priority;
  55         int        func_code;
  56 };
  57
  58 /* Offset into the private CCB area for storing our descriptor */
  59 #define targ_descr      periph_priv.entries[1].ptr
  60
  61 TAILQ_HEAD(descr_queue, targ_cmd_descr);
  62
  63 typedef enum {
  64         TARG_STATE_RESV         = 0x00, /* Invalid state */
  65         TARG_STATE_OPENED       = 0x01, /* Device opened, softc initialized */
  66         TARG_STATE_LUN_ENABLED  = 0x02  /* Device enabled for a path */
  67 } targ_state;
  68
  69 /* Per-instance device software context */
  70 struct targ_softc {
  71         /* CCBs (CTIOs, ATIOs, INOTs) pending on the controller */
  72         struct ccb_queue         pending_ccb_queue;
  73
  74         /* Command descriptors awaiting CTIO resources from the XPT */
  75         struct descr_queue       work_queue;
  76
  77         /* Command descriptors that have been aborted back to the user. */
  78         struct descr_queue       abort_queue;
  79
  80         /*
  81          * Queue of CCBs that have been copied out to userland, but our
  82          * userland daemon has not yet seen.
  83          */
  84         struct ccb_queue         user_ccb_queue;
  85
  86         struct cam_periph       *periph;
  87         struct cam_path         *path;
  88         targ_state               state;
  89         struct selinfo           read_select;
  90         struct devstat           device_stats;
  91 };
  92
  93 static d_open_t         targopen;
  94 static d_close_t        targclose;
  95 static d_read_t         targread;
  96 static d_write_t        targwrite;
  97 static d_ioctl_t        targioctl;
  98 static d_poll_t         targpoll;
  99 static d_kqfilter_t     targkqfilter;
 100 static void             targreadfiltdetach(struct knote *kn);
 101 static int              targreadfilt(struct knote *kn, long hint);
 102 static struct filterops targread_filtops =
 103         { 1, NULL, targreadfiltdetach, targreadfilt };
 104
 105 #define TARG_CDEV_MAJOR 65
 106 static struct cdevsw targ_cdevsw = {
 107         /* name */      "targ",
 108         /* maj */       TARG_CDEV_MAJOR,
 109         /* flags */     D_KQFILTER,
 110         /* port */      NULL,
 111         /* clone */     NULL,
 112
 113         /* open */      targopen,
 114         /* close */     targclose,
 115         /* read */      targread,
 116         /* write */     targwrite,
 117         /* ioctl */     targioctl,
 118         /* poll */      targpoll,
 119         /* mmap */      nommap,
 120         /* strategy */  nostrategy,
 121         /* dump */      nodump,
 122         /* psize */     nopsize,
 123         /* kqfilter */  targkqfilter
 124 };
 125
 126 static cam_status       targendislun(struct cam_path *path, int enable,
 127                                      int grp6_len, int grp7_len);
 128 static cam_status       targenable(struct targ_softc *softc,
 129                                    struct cam_path *path,
 130                                    int grp6_len, int grp7_len);
 131 static cam_status       targdisable(struct targ_softc *softc);
 132 static periph_ctor_t    targctor;
 133 static periph_dtor_t    targdtor;
 134 static periph_start_t   targstart;
 135 static int              targusermerge(struct targ_softc *softc,
 136                                       struct targ_cmd_descr *descr,
 137                                       union ccb *ccb);
 138 static int              targsendccb(struct targ_softc *softc, union ccb *ccb,
 139                                     struct targ_cmd_descr *descr);
 140 static void             targdone(struct cam_periph *periph,
 141                                  union  ccb *done_ccb);
 142 static int              targreturnccb(struct targ_softc *softc,
 143                                       union  ccb *ccb);
 144 static union ccb *      targgetccb(struct targ_softc *softc, xpt_opcode type,
 145                                    int priority);
 146 static void             targfreeccb(struct targ_softc *softc, union ccb *ccb);
 147 static struct targ_cmd_descr *
 148                         targgetdescr(struct targ_softc *softc);
 149 static periph_init_t    targinit;
 150 static void             targasync(void *callback_arg, u_int32_t code,
 151                                   struct cam_path *path, void *arg);
 152 static void             abort_all_pending(struct targ_softc *softc);
 153 static void             notify_user(struct targ_softc *softc);
 154 static int              targcamstatus(cam_status status);
 155 static size_t           targccblen(xpt_opcode func_code);
 156
 157 static struct periph_driver targdriver =
 158 {
 159         targinit, "targ",
 160         TAILQ_HEAD_INITIALIZER(targdriver.units), /* generation */ 0
 161 };
 162 DATA_SET(periphdriver_set, targdriver);
 163
 164 static MALLOC_DEFINE(M_TARG, "TARG", "TARG data");
 165
 166 /* Create softc and initialize it. Only one proc can open each targ device. */
 167 static int
 168 targopen(dev_t dev, int flags, int fmt, struct proc *p)
 169 {
 170         struct targ_softc *softc;
 171
 172         if (dev->si_drv1 != 0) {
 173                 return (EBUSY);
 174         }
 175
 176         /* Mark device busy before any potentially blocking operations */
 177         dev->si_drv1 = (void *)~0;
 178         reference_dev(dev);             /* save ref for later destroy_dev() */
 179
 180         /* Create the targ device, allocate its softc, initialize it */
 181         make_dev(&targ_cdevsw, minor(dev), UID_ROOT, GID_WHEEL, 0600,
 182                          "targ%d", lminor(dev));
 183         MALLOC(softc, struct targ_softc *, sizeof(*softc), M_TARG,
 184                M_INTWAIT | M_ZERO);
 185         dev->si_drv1 = softc;
 186         softc->state = TARG_STATE_OPENED;
 187         softc->periph = NULL;
 188         softc->path = NULL;
 189
 190         TAILQ_INIT(&softc->pending_ccb_queue);
 191         TAILQ_INIT(&softc->work_queue);
 192         TAILQ_INIT(&softc->abort_queue);
 193         TAILQ_INIT(&softc->user_ccb_queue);
 194
 195         return (0);
 196 }
 197
 198 /* Disable LUN if enabled and teardown softc */
 199 static int
 200 targclose(dev_t dev, int flag, int fmt, struct proc *p)
 201 {
 202         struct targ_softc     *softc;
 203         int    error;
 204
 205         softc = (struct targ_softc *)dev->si_drv1;
 206         error = targdisable(softc);
 207         if (error == CAM_REQ_CMP) {
 208                 dev->si_drv1 = 0;
 209                 if (softc->periph != NULL) {
 210                         cam_periph_invalidate(softc->periph);
 211                         softc->periph = NULL;
 212                 }
 213                 destroy_dev(dev);       /* eats the open ref */
 214                 FREE(softc, M_TARG);
 215         } else {
 216                 release_dev(dev);
 217         }
 218         return (error);
 219 }
 220
 221 /* Enable/disable LUNs, set debugging level */
 222 static int
 223 targioctl(dev_t dev, u_long cmd, caddr_t addr, int flag, struct proc *p)
 224 {
 225         struct targ_softc *softc;
 226         cam_status         status;
 227
 228         softc = (struct targ_softc *)dev->si_drv1;
 229
 230         switch (cmd) {
 231         case TARGIOCENABLE:
 232         {
 233                 struct ioc_enable_lun   *new_lun;
 234                 struct cam_path         *path;
 235
 236                 new_lun = (struct ioc_enable_lun *)addr;
 237                 status = xpt_create_path(&path, /*periph*/NULL,
 238                                          new_lun->path_id,
 239                                          new_lun->target_id,
 240                                          new_lun->lun_id);
 241                 if (status != CAM_REQ_CMP) {
 242                         printf("Couldn't create path, status %#x\n", status);
 243                         break;
 244                 }
 245                 status = targenable(softc, path, new_lun->grp6_len,
 246                                     new_lun->grp7_len);
 247                 xpt_free_path(path);
 248                 break;
 249         }
 250         case TARGIOCDISABLE:
 251                 status = targdisable(softc);
 252                 break;
 253         case TARGIOCDEBUG:
 254         {
 255 #ifdef  CAMDEBUG
 256                 struct ccb_debug cdbg;
 257
 258                 bzero(&cdbg, sizeof cdbg);
 259                 if (*((int *)addr) != 0)
 260                         cdbg.flags = CAM_DEBUG_PERIPH;
 261                 else
 262                         cdbg.flags = CAM_DEBUG_NONE;
 263                 xpt_setup_ccb(&cdbg.ccb_h, softc->path, /*priority*/0);
 264                 cdbg.ccb_h.func_code = XPT_DEBUG;
 265                 cdbg.ccb_h.cbfcnp = targdone;
 266
 267                 /* If no periph available, disallow debugging changes */
 268                 if ((softc->state & TARG_STATE_LUN_ENABLED) == 0) {
 269                         status = CAM_DEV_NOT_THERE;
 270                         break;
 271                 }
 272                 xpt_action((union ccb *)&cdbg);
 273                 status = cdbg.ccb_h.status & CAM_STATUS_MASK;
 274 #else
 275                 status = CAM_FUNC_NOTAVAIL;
 276 #endif
 277                 break;
 278         }
 279         default:
 280                 status = CAM_PROVIDE_FAIL;
 281                 break;
 282         }
 283
 284         return (targcamstatus(status));
 285 }
 286
 287 /* Writes are always ready, reads wait for user_ccb_queue or abort_queue */
 288 static int
 289 targpoll(dev_t dev, int poll_events, struct proc *p)
 290 {
 291         struct targ_softc *softc;
 292         int     revents;
 293
 294         softc = (struct targ_softc *)dev->si_drv1;
 295
 296         /* Poll for write() is always ok. */
 297         revents = poll_events & (POLLOUT | POLLWRNORM);
 298         if ((poll_events & (POLLIN | POLLRDNORM)) != 0) {
 299                 crit_enter();
 300                 /* Poll for read() depends on user and abort queues. */
 301                 if (!TAILQ_EMPTY(&softc->user_ccb_queue) ||
 302                     !TAILQ_EMPTY(&softc->abort_queue)) {
 303                         revents |= poll_events & (POLLIN | POLLRDNORM);
 304                 }
 305                 /* Only sleep if the user didn't poll for write. */
 306                 if (revents == 0)
 307                         selrecord(p, &softc->read_select);
 308                 crit_exit();
 309         }
 310
 311         return (revents);
 312 }
 313
 314 static int
 315 targkqfilter(dev_t dev, struct knote *kn)
 316 {
 317         struct  targ_softc *softc;
 318
 319         softc = (struct targ_softc *)dev->si_drv1;
 320         kn->kn_hook = (caddr_t)softc;
 321         kn->kn_fop = &targread_filtops;
 322         crit_enter();
 323         SLIST_INSERT_HEAD(&softc->read_select.si_note, kn, kn_selnext);
 324         crit_exit();
 325         return (0);
 326 }
 327
 328 static void
 329 targreadfiltdetach(struct knote *kn)
 330 {
 331         struct  targ_softc *softc;
 332
 333         softc = (struct targ_softc *)kn->kn_hook;
 334         crit_enter();
 335         SLIST_REMOVE(&softc->read_select.si_note, kn, knote, kn_selnext);
 336         crit_exit();
 337 }
 338
 339 /* Notify the user's kqueue when the user queue or abort queue gets a CCB */
 340 static int
 341 targreadfilt(struct knote *kn, long hint)
 342 {
 343         struct targ_softc *softc;
 344         int     retval;
 345
 346         softc = (struct targ_softc *)kn->kn_hook;
 347         crit_enter();
 348         retval = !TAILQ_EMPTY(&softc->user_ccb_queue) ||
 349                  !TAILQ_EMPTY(&softc->abort_queue);
 350         crit_exit();
 351         return (retval);
 352 }
 353
 354 /* Send the HBA the enable/disable message */
 355 static cam_status
 356 targendislun(struct cam_path *path, int enable, int grp6_len, int grp7_len)
 357 {
 358         struct ccb_en_lun en_ccb;
 359         cam_status        status;
 360
 361         /* Tell the lun to begin answering selects */
 362         xpt_setup_ccb(&en_ccb.ccb_h, path, /*priority*/1);
 363         en_ccb.ccb_h.func_code = XPT_EN_LUN;
 364         /* Don't need support for any vendor specific commands */
 365         en_ccb.grp6_len = grp6_len;
 366         en_ccb.grp7_len = grp7_len;
 367         en_ccb.enable = enable ? 1 : 0;
 368         xpt_action((union ccb *)&en_ccb);
 369         status = en_ccb.ccb_h.status & CAM_STATUS_MASK;
 370         if (status != CAM_REQ_CMP) {
 371                 xpt_print_path(path);
 372                 printf("%sable lun CCB rejected, status %#x\n",
 373                        enable ? "en" : "dis", status);
 374         }
 375         return (status);
 376 }
 377
 378 /* Enable target mode on a LUN, given its path */
 379 static cam_status
 380 targenable(struct targ_softc *softc, struct cam_path *path, int grp6_len,
 381            int grp7_len)
 382 {
 383         struct cam_periph *periph;
 384         struct ccb_pathinq cpi;
 385         cam_status         status;
 386
 387         if ((softc->state & TARG_STATE_LUN_ENABLED) != 0)
 388                 return (CAM_LUN_ALRDY_ENA);
 389
 390         /* Make sure SIM supports target mode */
 391         xpt_setup_ccb(&cpi.ccb_h, path, /*priority*/1);
 392         cpi.ccb_h.func_code = XPT_PATH_INQ;
 393         xpt_action((union ccb *)&cpi);
 394         status = cpi.ccb_h.status & CAM_STATUS_MASK;
 395         if (status != CAM_REQ_CMP) {
 396                 printf("pathinq failed, status %#x\n", status);
 397                 goto enable_fail;
 398         }
 399         if ((cpi.target_sprt & PIT_PROCESSOR) == 0) {
 400                 printf("controller does not support target mode\n");
 401                 status = CAM_FUNC_NOTAVAIL;
 402                 goto enable_fail;
 403         }
 404
 405         /* Destroy any periph on our path if it is disabled */
 406         periph = cam_periph_find(path, "targ");
 407         if (periph != NULL) {
 408                 struct targ_softc *del_softc;
 409
 410                 del_softc = (struct targ_softc *)periph->softc;
 411                 if ((del_softc->state & TARG_STATE_LUN_ENABLED) == 0) {
 412                         cam_periph_invalidate(del_softc->periph);
 413                         del_softc->periph = NULL;
 414                 } else {
 415                         printf("Requested path still in use by targ%d\n",
 416                                periph->unit_number);
 417                         status = CAM_LUN_ALRDY_ENA;
 418                         goto enable_fail;
 419                 }
 420         }
 421
 422         /* Create a periph instance attached to this path */
 423         status = cam_periph_alloc(targctor, NULL, targdtor, targstart,
 424                         "targ", CAM_PERIPH_BIO, path, targasync, 0, softc);
 425         if (status != CAM_REQ_CMP) {
 426                 printf("cam_periph_alloc failed, status %#x\n", status);
 427                 goto enable_fail;
 428         }
 429
 430         /* Ensure that the periph now exists. */
 431         if (cam_periph_find(path, "targ") == NULL) {
 432                 panic("targenable: succeeded but no periph?");
 433                 /* NOTREACHED */
 434         }
 435
 436         /* Send the enable lun message */
 437         status = targendislun(path, /*enable*/1, grp6_len, grp7_len);
 438         if (status != CAM_REQ_CMP) {
 439                 printf("enable lun failed, status %#x\n", status);
 440                 goto enable_fail;
 441         }
 442         softc->state |= TARG_STATE_LUN_ENABLED;
 443
 444 enable_fail:
 445         return (status);
 446 }
 447
 448 /* Disable this softc's target instance if enabled */
 449 static cam_status
 450 targdisable(struct targ_softc *softc)
 451 {
 452         cam_status status;
 453
 454         if ((softc->state & TARG_STATE_LUN_ENABLED) == 0)
 455                 return (CAM_REQ_CMP);
 456
 457         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targdisable\n"));
 458
 459         /* Abort any ccbs pending on the controller */
 460         crit_enter();
 461         abort_all_pending(softc);
 462         crit_exit();
 463
 464         /* Disable this lun */
 465         status = targendislun(softc->path, /*enable*/0,
 466                               /*grp6_len*/0, /*grp7_len*/0);
 467         if (status == CAM_REQ_CMP)
 468                 softc->state &= ~TARG_STATE_LUN_ENABLED;
 469         else
 470                 printf("Disable lun failed, status %#x\n", status);
 471
 472         return (status);
 473 }
 474
 475 /* Initialize a periph (called from cam_periph_alloc) */
 476 static cam_status
 477 targctor(struct cam_periph *periph, void *arg)
 478 {
 479         struct targ_softc *softc;
 480
 481         /* Store pointer to softc for periph-driven routines */
 482         softc = (struct targ_softc *)arg;
 483         periph->softc = softc;
 484         softc->periph = periph;
 485         softc->path = periph->path;
 486         return (CAM_REQ_CMP);
 487 }
 488
 489 static void
 490 targdtor(struct cam_periph *periph)
 491 {
 492         struct targ_softc     *softc;
 493         struct ccb_hdr        *ccb_h;
 494         struct targ_cmd_descr *descr;
 495
 496         softc = (struct targ_softc *)periph->softc;
 497
 498         /*
 499          * targdisable() aborts CCBs back to the user and leaves them
 500          * on user_ccb_queue and abort_queue in case the user is still
 501          * interested in them.  We free them now.
 502          */
 503         while ((ccb_h = TAILQ_FIRST(&softc->user_ccb_queue)) != NULL) {
 504                 TAILQ_REMOVE(&softc->user_ccb_queue, ccb_h, periph_links.tqe);
 505                 targfreeccb(softc, (union ccb *)ccb_h);
 506         }
 507         while ((descr = TAILQ_FIRST(&softc->abort_queue)) != NULL) {
 508                 TAILQ_REMOVE(&softc->abort_queue, descr, tqe);
 509                 FREE(descr, M_TARG);
 510         }
 511
 512         softc->periph = NULL;
 513         softc->path = NULL;
 514         periph->softc = NULL;
 515 }
 516
 517 /* Receive CCBs from user mode proc and send them to the HBA */
 518 static int
 519 targwrite(dev_t dev, struct uio *uio, int ioflag)
 520 {
 521         union ccb *user_ccb;
 522         struct targ_softc *softc;
 523         struct targ_cmd_descr *descr;
 524         int write_len, error;
 525         int func_code, priority;
 526
 527         softc = (struct targ_softc *)dev->si_drv1;
 528         write_len = error = 0;
 529         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 530                   ("write - uio_resid %d\n", uio->uio_resid));
 531         while (uio->uio_resid >= sizeof(user_ccb) && error == 0) {
 532                 union ccb *ccb;
 533
 534                 error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
 535                 if (error != 0) {
 536                         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 537                                   ("write - uiomove failed (%d)\n", error));
 538                         break;
 539                 }
 540                 priority = fuword(&user_ccb->ccb_h.pinfo.priority);
 541                 if (priority == -1) {
 542                         error = EINVAL;
 543                         break;
 544                 }
 545                 func_code = fuword(&user_ccb->ccb_h.func_code);
 546                 switch (func_code) {
 547                 case XPT_ACCEPT_TARGET_IO:
 548                 case XPT_IMMED_NOTIFY:
 549                         ccb = targgetccb(softc, func_code, priority);
 550                         descr = (struct targ_cmd_descr *)ccb->ccb_h.targ_descr;
 551                         descr->user_ccb = user_ccb;
 552                         descr->func_code = func_code;
 553                         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 554                                   ("Sent ATIO/INOT (%p)\n", user_ccb));
 555                         xpt_action(ccb);
 556                         crit_enter();
 557                         TAILQ_INSERT_TAIL(&softc->pending_ccb_queue,
 558                                           &ccb->ccb_h,
 559                                           periph_links.tqe);
 560                         crit_exit();
 561                         break;
 562                 default:
 563                         if ((func_code & XPT_FC_QUEUED) != 0) {
 564                                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 565                                           ("Sending queued ccb %#x (%p)\n",
 566                                           func_code, user_ccb));
 567                                 descr = targgetdescr(softc);
 568                                 descr->user_ccb = user_ccb;
 569                                 descr->priority = priority;
 570                                 descr->func_code = func_code;
 571                                 crit_enter();
 572                                 TAILQ_INSERT_TAIL(&softc->work_queue,
 573                                                   descr, tqe);
 574                                 crit_exit();
 575                                 xpt_schedule(softc->periph, priority);
 576                         } else {
 577                                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 578                                           ("Sending inline ccb %#x (%p)\n",
 579                                           func_code, user_ccb));
 580                                 ccb = targgetccb(softc, func_code, priority);
 581                                 descr = (struct targ_cmd_descr *)
 582                                          ccb->ccb_h.targ_descr;
 583                                 descr->user_ccb = user_ccb;
 584                                 descr->priority = priority;
 585                                 descr->func_code = func_code;
 586                                 if (targusermerge(softc, descr, ccb) != EFAULT)
 587                                         targsendccb(softc, ccb, descr);
 588                                 targreturnccb(softc, ccb);
 589                         }
 590                         break;
 591                 }
 592                 write_len += sizeof(user_ccb);
 593         }
 594
 595         /*
 596          * If we've successfully taken in some amount of
 597          * data, return success for that data first.  If
 598          * an error is persistent, it will be reported
 599          * on the next write.
 600          */
 601         if (error != 0 && write_len == 0)
 602                 return (error);
 603         if (write_len == 0 && uio->uio_resid != 0)
 604                 return (ENOSPC);
 605         return (0);
 606 }
 607
 608 /* Process requests (descrs) via the periph-supplied CCBs */
 609 static void
 610 targstart(struct cam_periph *periph, union ccb *start_ccb)
 611 {
 612         struct targ_softc *softc;
 613         struct targ_cmd_descr *descr, *next_descr;
 614         int error;
 615
 616         softc = (struct targ_softc *)periph->softc;
 617         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targstart %p\n", start_ccb));
 618
 619         crit_enter();
 620         descr = TAILQ_FIRST(&softc->work_queue);
 621         if (descr == NULL) {
 622                 crit_exit();
 623                 xpt_release_ccb(start_ccb);
 624         } else {
 625                 TAILQ_REMOVE(&softc->work_queue, descr, tqe);
 626                 next_descr = TAILQ_FIRST(&softc->work_queue);
 627                 crit_exit();
 628
 629                 /* Initiate a transaction using the descr and supplied CCB */
 630                 error = targusermerge(softc, descr, start_ccb);
 631                 if (error == 0)
 632                         error = targsendccb(softc, start_ccb, descr);
 633                 if (error != 0) {
 634                         xpt_print_path(periph->path);
 635                         printf("targsendccb failed, err %d\n", error);
 636                         xpt_release_ccb(start_ccb);
 637                         suword(&descr->user_ccb->ccb_h.status,
 638                                CAM_REQ_CMP_ERR);
 639                         crit_enter();
 640                         TAILQ_INSERT_TAIL(&softc->abort_queue, descr, tqe);
 641                         crit_exit();
 642                         notify_user(softc);
 643                 }
 644
 645                 /* If we have more work to do, stay scheduled */
 646                 if (next_descr != NULL)
 647                         xpt_schedule(periph, next_descr->priority);
 648         }
 649 }
 650
 651 static int
 652 targusermerge(struct targ_softc *softc, struct targ_cmd_descr *descr,
 653               union ccb *ccb)
 654 {
 655         struct ccb_hdr *u_ccbh, *k_ccbh;
 656         size_t ccb_len;
 657         int error;
 658
 659         u_ccbh = &descr->user_ccb->ccb_h;
 660         k_ccbh = &ccb->ccb_h;
 661
 662         /*
 663          * There are some fields in the CCB header that need to be
 664          * preserved, the rest we get from the user ccb. (See xpt_merge_ccb)
 665          */
 666         xpt_setup_ccb(k_ccbh, softc->path, descr->priority);
 667         k_ccbh->retry_count = fuword(&u_ccbh->retry_count);
 668         k_ccbh->func_code = descr->func_code;
 669         k_ccbh->flags = fuword(&u_ccbh->flags);
 670         k_ccbh->timeout = fuword(&u_ccbh->timeout);
 671         ccb_len = targccblen(k_ccbh->func_code) - sizeof(struct ccb_hdr);
 672         error = copyin(u_ccbh + 1, k_ccbh + 1, ccb_len);
 673         if (error != 0) {
 674                 k_ccbh->status = CAM_REQ_CMP_ERR;
 675                 return (error);
 676         }
 677
 678         /* Translate usermode abort_ccb pointer to its kernel counterpart */
 679         if (k_ccbh->func_code == XPT_ABORT) {
 680                 struct ccb_abort *cab;
 681                 struct ccb_hdr *ccb_h;
 682                 int s;
 683
 684                 cab = (struct ccb_abort *)ccb;
 685                 crit_enter();
 686                 TAILQ_FOREACH(ccb_h, &softc->pending_ccb_queue,
 687                     periph_links.tqe) {
 688                         struct targ_cmd_descr *ab_descr;
 689
 690                         ab_descr = (struct targ_cmd_descr *)ccb_h->targ_descr;
 691                         if (ab_descr->user_ccb == cab->abort_ccb) {
 692                                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 693                                           ("Changing abort for %p to %p\n",
 694                                           cab->abort_ccb, ccb_h));
 695                                 cab->abort_ccb = (union ccb *)ccb_h;
 696                                 break;
 697                         }
 698                 }
 699                 crit_exit();
 700                 /* CCB not found, set appropriate status */
 701                 if (ccb_h == NULL) {
 702                         k_ccbh->status = CAM_PATH_INVALID;
 703                         error = ESRCH;
 704                 }
 705         }
 706
 707         return (error);
 708 }
 709
 710 /* Build and send a kernel CCB formed from descr->user_ccb */
 711 static int
 712 targsendccb(struct targ_softc *softc, union ccb *ccb,
 713             struct targ_cmd_descr *descr)
 714 {
 715         struct cam_periph_map_info *mapinfo;
 716         struct ccb_hdr *ccb_h;
 717         int error;
 718
 719         ccb_h = &ccb->ccb_h;
 720         mapinfo = &descr->mapinfo;
 721         mapinfo->num_bufs_used = 0;
 722
 723         /*
 724          * There's no way for the user to have a completion
 725          * function, so we put our own completion function in here.
 726          * We also stash in a reference to our descriptor so targreturnccb()
 727          * can find our mapping info.
 728          */
 729         ccb_h->cbfcnp = targdone;
 730         ccb_h->targ_descr = descr;
 731
 732         /*
 733          * We only attempt to map the user memory into kernel space
 734          * if they haven't passed in a physical memory pointer,
 735          * and if there is actually an I/O operation to perform.
 736          * Right now cam_periph_mapmem() only supports SCSI and device
 737          * match CCBs.  For the SCSI CCBs, we only pass the CCB in if
 738          * there's actually data to map.  cam_periph_mapmem() will do the
 739          * right thing, even if there isn't data to map, but since CCBs
 740          * without data are a reasonably common occurance (e.g. test unit
 741          * ready), it will save a few cycles if we check for it here.
 742          */
 743         if (((ccb_h->flags & CAM_DATA_PHYS) == 0)
 744          && (((ccb_h->func_code == XPT_CONT_TARGET_IO)
 745             && ((ccb_h->flags & CAM_DIR_MASK) != CAM_DIR_NONE))
 746           || (ccb_h->func_code == XPT_DEV_MATCH))) {
 747
 748                 error = cam_periph_mapmem(ccb, mapinfo);
 749
 750                 /*
 751                  * cam_periph_mapmem returned an error, we can't continue.
 752                  * Return the error to the user.
 753                  */
 754                 if (error) {
 755                         ccb_h->status = CAM_REQ_CMP_ERR;
 756                         mapinfo->num_bufs_used = 0;
 757                         return (error);
 758                 }
 759         }
 760
 761         /*
 762          * Once queued on the pending CCB list, this CCB will be protected
 763          * by our error recovery handler.
 764          */
 765         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("sendccb %p\n", ccb));
 766         if (XPT_FC_IS_QUEUED(ccb)) {
 767                 crit_enter();
 768                 TAILQ_INSERT_TAIL(&softc->pending_ccb_queue, ccb_h,
 769                                   periph_links.tqe);
 770                 crit_exit();
 771         }
 772         xpt_action(ccb);
 773
 774         return (0);
 775 }
 776
 777 /* Completion routine for CCBs (called in a critical section) */
 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;
 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         crit_enter();
 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                                         crit_exit();
 848                                         goto read_fail;
 849                                 }
 850                         }
 851                 } else {
 852                         crit_exit();
 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                 crit_exit();
 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                 crit_enter();
 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                 crit_exit();
 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                 crit_enter();
 898                 user_descr = TAILQ_FIRST(abort_queue);
 899         }
 900         crit_exit();
 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_INTWAIT);
 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),
 999                 M_TARG, M_INTWAIT);
1000         descr->mapinfo.num_bufs_used = 0;
1001         return (descr);
1002 }
1003
1004 static void
1005 targinit(void)
1006 {
1007         cdevsw_add(&targ_cdevsw, 0, 0);
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 }