hw/scsi-bus.c

   1 #include "hw.h"
   2 #include "qemu-error.h"
   3 #include "scsi.h"
   4 #include "scsi-defs.h"
   5 #include "qdev.h"
   6 #include "blockdev.h"
   7 #include "trace.h"
   8
   9 static char *scsibus_get_fw_dev_path(DeviceState *dev);
  10 static int scsi_req_parse(SCSICommand *cmd, SCSIDevice *dev, uint8_t *buf);
  11 static void scsi_req_dequeue(SCSIRequest *req);
  12 static int scsi_build_sense(uint8_t *in_buf, int in_len,
  13                             uint8_t *buf, int len, bool fixed);
  14
  15 static struct BusInfo scsi_bus_info = {
  16     .name  = "SCSI",
  17     .size  = sizeof(SCSIBus),
  18     .get_fw_dev_path = scsibus_get_fw_dev_path,
  19     .props = (Property[]) {
  20         DEFINE_PROP_UINT32("channel", SCSIDevice, channel, 0),
  21         DEFINE_PROP_UINT32("scsi-id", SCSIDevice, id, -1),
  22         DEFINE_PROP_UINT32("lun", SCSIDevice, lun, -1),
  23         DEFINE_PROP_END_OF_LIST(),
  24     },
  25 };
  26 static int next_scsi_bus;
  27
  28 /* Create a scsi bus, and attach devices to it.  */
  29 void scsi_bus_new(SCSIBus *bus, DeviceState *host, const SCSIBusInfo *info)
  30 {
  31     qbus_create_inplace(&bus->qbus, &scsi_bus_info, host, NULL);
  32     bus->busnr = next_scsi_bus++;
  33     bus->info = info;
  34     bus->qbus.allow_hotplug = 1;
  35 }
  36
  37 static void scsi_dma_restart_bh(void *opaque)
  38 {
  39     SCSIDevice *s = opaque;
  40     SCSIRequest *req, *next;
  41
  42     qemu_bh_delete(s->bh);
  43     s->bh = NULL;
  44
  45     QTAILQ_FOREACH_SAFE(req, &s->requests, next, next) {
  46         scsi_req_ref(req);
  47         if (req->retry) {
  48             req->retry = false;
  49             switch (req->cmd.mode) {
  50             case SCSI_XFER_FROM_DEV:
  51             case SCSI_XFER_TO_DEV:
  52                 scsi_req_continue(req);
  53                 break;
  54             case SCSI_XFER_NONE:
  55                 scsi_req_dequeue(req);
  56                 scsi_req_enqueue(req);
  57                 break;
  58             }
  59         }
  60         scsi_req_unref(req);
  61     }
  62 }
  63
  64 void scsi_req_retry(SCSIRequest *req)
  65 {
  66     /* No need to save a reference, because scsi_dma_restart_bh just
  67      * looks at the request list.  */
  68     req->retry = true;
  69 }
  70
  71 static void scsi_dma_restart_cb(void *opaque, int running, RunState state)
  72 {
  73     SCSIDevice *s = opaque;
  74
  75     if (!running) {
  76         return;
  77     }
  78     if (!s->bh) {
  79         s->bh = qemu_bh_new(scsi_dma_restart_bh, s);
  80         qemu_bh_schedule(s->bh);
  81     }
  82 }
  83
  84 static int scsi_qdev_init(DeviceState *qdev, DeviceInfo *base)
  85 {
  86     SCSIDevice *dev = DO_UPCAST(SCSIDevice, qdev, qdev);
  87     SCSIDeviceInfo *info = DO_UPCAST(SCSIDeviceInfo, qdev, base);
  88     SCSIBus *bus = DO_UPCAST(SCSIBus, qbus, dev->qdev.parent_bus);
  89     SCSIDevice *d;
  90     int rc = -1;
  91
  92     if (dev->channel > bus->info->max_channel) {
  93         error_report("bad scsi channel id: %d", dev->channel);
  94         goto err;
  95     }
  96     if (dev->id != -1 && dev->id > bus->info->max_target) {
  97         error_report("bad scsi device id: %d", dev->id);
  98         goto err;
  99     }
 100
 101     if (dev->id == -1) {
 102         int id = -1;
 103         if (dev->lun == -1) {
 104             dev->lun = 0;
 105         }
 106         do {
 107             d = scsi_device_find(bus, dev->channel, ++id, dev->lun);
 108         } while (d && d->lun == dev->lun && id <= bus->info->max_target);
 109         if (id > bus->info->max_target) {
 110             error_report("no free target");
 111             goto err;
 112         }
 113         dev->id = id;
 114     } else if (dev->lun == -1) {
 115         int lun = -1;
 116         do {
 117             d = scsi_device_find(bus, dev->channel, dev->id, ++lun);
 118         } while (d && d->lun == lun && lun < bus->info->max_lun);
 119         if (lun > bus->info->max_lun) {
 120             error_report("no free lun");
 121             goto err;
 122         }
 123         dev->lun = lun;
 124     } else {
 125         d = scsi_device_find(bus, dev->channel, dev->id, dev->lun);
 126         if (dev->lun == d->lun && dev != d) {
 127             qdev_free(&d->qdev);
 128         }
 129     }
 130
 131     dev->info = info;
 132     QTAILQ_INIT(&dev->requests);
 133     rc = dev->info->init(dev);
 134     if (rc == 0) {
 135         dev->vmsentry = qemu_add_vm_change_state_handler(scsi_dma_restart_cb,
 136                                                          dev);
 137     }
 138
 139 err:
 140     return rc;
 141 }
 142
 143 static int scsi_qdev_exit(DeviceState *qdev)
 144 {
 145     SCSIDevice *dev = DO_UPCAST(SCSIDevice, qdev, qdev);
 146
 147     if (dev->vmsentry) {
 148         qemu_del_vm_change_state_handler(dev->vmsentry);
 149     }
 150     if (dev->info->destroy) {
 151         dev->info->destroy(dev);
 152     }
 153     return 0;
 154 }
 155
 156 void scsi_qdev_register(SCSIDeviceInfo *info)
 157 {
 158     info->qdev.bus_info = &scsi_bus_info;
 159     info->qdev.init     = scsi_qdev_init;
 160     info->qdev.unplug   = qdev_simple_unplug_cb;
 161     info->qdev.exit     = scsi_qdev_exit;
 162     qdev_register(&info->qdev);
 163 }
 164
 165 /* handle legacy '-drive if=scsi,...' cmd line args */
 166 SCSIDevice *scsi_bus_legacy_add_drive(SCSIBus *bus, BlockDriverState *bdrv,
 167                                       int unit, bool removable)
 168 {
 169     const char *driver;
 170     DeviceState *dev;
 171
 172     driver = bdrv_is_sg(bdrv) ? "scsi-generic" : "scsi-disk";
 173     dev = qdev_create(&bus->qbus, driver);
 174     qdev_prop_set_uint32(dev, "scsi-id", unit);
 175     if (qdev_prop_exists(dev, "removable")) {
 176         qdev_prop_set_bit(dev, "removable", removable);
 177     }
 178     if (qdev_prop_set_drive(dev, "drive", bdrv) < 0) {
 179         qdev_free(dev);
 180         return NULL;
 181     }
 182     if (qdev_init(dev) < 0)
 183         return NULL;
 184     return DO_UPCAST(SCSIDevice, qdev, dev);
 185 }
 186
 187 int scsi_bus_legacy_handle_cmdline(SCSIBus *bus)
 188 {
 189     Location loc;
 190     DriveInfo *dinfo;
 191     int res = 0, unit;
 192
 193     loc_push_none(&loc);
 194     for (unit = 0; unit < bus->info->max_target; unit++) {
 195         dinfo = drive_get(IF_SCSI, bus->busnr, unit);
 196         if (dinfo == NULL) {
 197             continue;
 198         }
 199         qemu_opts_loc_restore(dinfo->opts);
 200         if (!scsi_bus_legacy_add_drive(bus, dinfo->bdrv, unit, false)) {
 201             res = -1;
 202             break;
 203         }
 204     }
 205     loc_pop(&loc);
 206     return res;
 207 }
 208
 209 /* SCSIReqOps implementation for invalid commands.  */
 210
 211 static int32_t scsi_invalid_command(SCSIRequest *req, uint8_t *buf)
 212 {
 213     scsi_req_build_sense(req, SENSE_CODE(INVALID_OPCODE));
 214     scsi_req_complete(req, CHECK_CONDITION);
 215     return 0;
 216 }
 217
 218 static const struct SCSIReqOps reqops_invalid_opcode = {
 219     .size         = sizeof(SCSIRequest),
 220     .send_command = scsi_invalid_command
 221 };
 222
 223 /* SCSIReqOps implementation for unit attention conditions.  */
 224
 225 static int32_t scsi_unit_attention(SCSIRequest *req, uint8_t *buf)
 226 {
 227     if (req->dev && req->dev->unit_attention.key == UNIT_ATTENTION) {
 228         scsi_req_build_sense(req, req->dev->unit_attention);
 229     } else if (req->bus->unit_attention.key == UNIT_ATTENTION) {
 230         scsi_req_build_sense(req, req->bus->unit_attention);
 231     }
 232     scsi_req_complete(req, CHECK_CONDITION);
 233     return 0;
 234 }
 235
 236 static const struct SCSIReqOps reqops_unit_attention = {
 237     .size         = sizeof(SCSIRequest),
 238     .send_command = scsi_unit_attention
 239 };
 240
 241 /* SCSIReqOps implementation for REPORT LUNS and for commands sent to
 242    an invalid LUN.  */
 243
 244 typedef struct SCSITargetReq SCSITargetReq;
 245
 246 struct SCSITargetReq {
 247     SCSIRequest req;
 248     int len;
 249     uint8_t buf[2056];
 250 };
 251
 252 static void store_lun(uint8_t *outbuf, int lun)
 253 {
 254     if (lun < 256) {
 255         outbuf[1] = lun;
 256         return;
 257     }
 258     outbuf[1] = (lun & 255);
 259     outbuf[0] = (lun >> 8) | 0x40;
 260 }
 261
 262 static bool scsi_target_emulate_report_luns(SCSITargetReq *r)
 263 {
 264     DeviceState *qdev;
 265     int i, len, n;
 266     int channel, id;
 267     bool found_lun0;
 268
 269     if (r->req.cmd.xfer < 16) {
 270         return false;
 271     }
 272     if (r->req.cmd.buf[2] > 2) {
 273         return false;
 274     }
 275     channel = r->req.dev->channel;
 276     id = r->req.dev->id;
 277     found_lun0 = false;
 278     n = 0;
 279     QTAILQ_FOREACH(qdev, &r->req.bus->qbus.children, sibling) {
 280         SCSIDevice *dev = DO_UPCAST(SCSIDevice, qdev, qdev);
 281
 282         if (dev->channel == channel && dev->id == id) {
 283             if (dev->lun == 0) {
 284                 found_lun0 = true;
 285             }
 286             n += 8;
 287         }
 288     }
 289     if (!found_lun0) {
 290         n += 8;
 291     }
 292     len = MIN(n + 8, r->req.cmd.xfer & ~7);
 293     if (len > sizeof(r->buf)) {
 294         /* TODO: > 256 LUNs? */
 295         return false;
 296     }
 297
 298     memset(r->buf, 0, len);
 299     stl_be_p(&r->buf, n);
 300     i = found_lun0 ? 8 : 16;
 301     QTAILQ_FOREACH(qdev, &r->req.bus->qbus.children, sibling) {
 302         SCSIDevice *dev = DO_UPCAST(SCSIDevice, qdev, qdev);
 303
 304         if (dev->channel == channel && dev->id == id) {
 305             store_lun(&r->buf[i], dev->lun);
 306             i += 8;
 307         }
 308     }
 309     assert(i == n + 8);
 310     r->len = len;
 311     return true;
 312 }
 313
 314 static bool scsi_target_emulate_inquiry(SCSITargetReq *r)
 315 {
 316     assert(r->req.dev->lun != r->req.lun);
 317     if (r->req.cmd.buf[1] & 0x2) {
 318         /* Command support data - optional, not implemented */
 319         return false;
 320     }
 321
 322     if (r->req.cmd.buf[1] & 0x1) {
 323         /* Vital product data */
 324         uint8_t page_code = r->req.cmd.buf[2];
 325         if (r->req.cmd.xfer < 4) {
 326             return false;
 327         }
 328
 329         r->buf[r->len++] = page_code ; /* this page */
 330         r->buf[r->len++] = 0x00;
 331
 332         switch (page_code) {
 333         case 0x00: /* Supported page codes, mandatory */
 334         {
 335             int pages;
 336             pages = r->len++;
 337             r->buf[r->len++] = 0x00; /* list of supported pages (this page) */
 338             r->buf[pages] = r->len - pages - 1; /* number of pages */
 339             break;
 340         }
 341         default:
 342             return false;
 343         }
 344         /* done with EVPD */
 345         assert(r->len < sizeof(r->buf));
 346         r->len = MIN(r->req.cmd.xfer, r->len);
 347         return true;
 348     }
 349
 350     /* Standard INQUIRY data */
 351     if (r->req.cmd.buf[2] != 0) {
 352         return false;
 353     }
 354
 355     /* PAGE CODE == 0 */
 356     if (r->req.cmd.xfer < 5) {
 357         return -1;
 358     }
 359
 360     r->len = MIN(r->req.cmd.xfer, 36);
 361     memset(r->buf, 0, r->len);
 362     if (r->req.lun != 0) {
 363         r->buf[0] = TYPE_NO_LUN;
 364     } else {
 365         r->buf[0] = TYPE_NOT_PRESENT | TYPE_INACTIVE;
 366         r->buf[2] = 5; /* Version */
 367         r->buf[3] = 2 | 0x10; /* HiSup, response data format */
 368         r->buf[4] = r->len - 5; /* Additional Length = (Len - 1) - 4 */
 369         r->buf[7] = 0x10 | (r->req.bus->info->tcq ? 0x02 : 0); /* Sync, TCQ.  */
 370         memcpy(&r->buf[8], "QEMU    ", 8);
 371         memcpy(&r->buf[16], "QEMU TARGET     ", 16);
 372         strncpy((char *) &r->buf[32], QEMU_VERSION, 4);
 373     }
 374     return true;
 375 }
 376
 377 static int32_t scsi_target_send_command(SCSIRequest *req, uint8_t *buf)
 378 {
 379     SCSITargetReq *r = DO_UPCAST(SCSITargetReq, req, req);
 380
 381     switch (buf[0]) {
 382     case REPORT_LUNS:
 383         if (!scsi_target_emulate_report_luns(r)) {
 384             goto illegal_request;
 385         }
 386         break;
 387     case INQUIRY:
 388         if (!scsi_target_emulate_inquiry(r)) {
 389             goto illegal_request;
 390         }
 391         break;
 392     case REQUEST_SENSE:
 393         if (req->cmd.xfer < 4) {
 394             goto illegal_request;
 395         }
 396         r->len = scsi_device_get_sense(r->req.dev, r->buf,
 397                                        MIN(req->cmd.xfer, sizeof r->buf),
 398                                        (req->cmd.buf[1] & 1) == 0);
 399         if (r->req.dev->sense_is_ua) {
 400             if (r->req.dev->info->unit_attention_reported) {
 401                 r->req.dev->info->unit_attention_reported(req->dev);
 402             }
 403             r->req.dev->sense_len = 0;
 404             r->req.dev->sense_is_ua = false;
 405         }
 406         break;
 407     default:
 408         scsi_req_build_sense(req, SENSE_CODE(LUN_NOT_SUPPORTED));
 409         scsi_req_complete(req, CHECK_CONDITION);
 410         return 0;
 411     illegal_request:
 412         scsi_req_build_sense(req, SENSE_CODE(INVALID_FIELD));
 413         scsi_req_complete(req, CHECK_CONDITION);
 414         return 0;
 415     }
 416
 417     if (!r->len) {
 418         scsi_req_complete(req, GOOD);
 419     }
 420     return r->len;
 421 }
 422
 423 static void scsi_target_read_data(SCSIRequest *req)
 424 {
 425     SCSITargetReq *r = DO_UPCAST(SCSITargetReq, req, req);
 426     uint32_t n;
 427
 428     n = r->len;
 429     if (n > 0) {
 430         r->len = 0;
 431         scsi_req_data(&r->req, n);
 432     } else {
 433         scsi_req_complete(&r->req, GOOD);
 434     }
 435 }
 436
 437 static uint8_t *scsi_target_get_buf(SCSIRequest *req)
 438 {
 439     SCSITargetReq *r = DO_UPCAST(SCSITargetReq, req, req);
 440
 441     return r->buf;
 442 }
 443
 444 static const struct SCSIReqOps reqops_target_command = {
 445     .size         = sizeof(SCSITargetReq),
 446     .send_command = scsi_target_send_command,
 447     .read_data    = scsi_target_read_data,
 448     .get_buf      = scsi_target_get_buf,
 449 };
 450
 451
 452 SCSIRequest *scsi_req_alloc(const SCSIReqOps *reqops, SCSIDevice *d,
 453                             uint32_t tag, uint32_t lun, void *hba_private)
 454 {
 455     SCSIRequest *req;
 456
 457     req = g_malloc0(reqops->size);
 458     req->refcount = 1;
 459     req->bus = scsi_bus_from_device(d);
 460     req->dev = d;
 461     req->tag = tag;
 462     req->lun = lun;
 463     req->hba_private = hba_private;
 464     req->status = -1;
 465     req->sense_len = 0;
 466     req->ops = reqops;
 467     trace_scsi_req_alloc(req->dev->id, req->lun, req->tag);
 468     return req;
 469 }
 470
 471 SCSIRequest *scsi_req_new(SCSIDevice *d, uint32_t tag, uint32_t lun,
 472                           uint8_t *buf, void *hba_private)
 473 {
 474     SCSIBus *bus = DO_UPCAST(SCSIBus, qbus, d->qdev.parent_bus);
 475     SCSIRequest *req;
 476     SCSICommand cmd;
 477
 478     if (scsi_req_parse(&cmd, d, buf) != 0) {
 479         trace_scsi_req_parse_bad(d->id, lun, tag, buf[0]);
 480         req = scsi_req_alloc(&reqops_invalid_opcode, d, tag, lun, hba_private);
 481     } else {
 482         trace_scsi_req_parsed(d->id, lun, tag, buf[0],
 483                               cmd.mode, cmd.xfer);
 484         if (cmd.lba != -1) {
 485             trace_scsi_req_parsed_lba(d->id, lun, tag, buf[0],
 486                                       cmd.lba);
 487         }
 488
 489         if ((d->unit_attention.key == UNIT_ATTENTION ||
 490              bus->unit_attention.key == UNIT_ATTENTION) &&
 491             (buf[0] != INQUIRY &&
 492              buf[0] != REPORT_LUNS &&
 493              buf[0] != GET_CONFIGURATION &&
 494              buf[0] != GET_EVENT_STATUS_NOTIFICATION &&
 495
 496              /*
 497               * If we already have a pending unit attention condition,
 498               * report this one before triggering another one.
 499               */
 500              !(buf[0] == REQUEST_SENSE && d->sense_is_ua))) {
 501             req = scsi_req_alloc(&reqops_unit_attention, d, tag, lun,
 502                                  hba_private);
 503         } else if (lun != d->lun ||
 504             buf[0] == REPORT_LUNS ||
 505             buf[0] == REQUEST_SENSE) {
 506             req = scsi_req_alloc(&reqops_target_command, d, tag, lun,
 507                                  hba_private);
 508         } else {
 509             req = d->info->alloc_req(d, tag, lun, buf, hba_private);
 510         }
 511     }
 512
 513     req->cmd = cmd;
 514     switch (buf[0]) {
 515     case INQUIRY:
 516         trace_scsi_inquiry(d->id, lun, tag, cmd.buf[1], cmd.buf[2]);
 517         break;
 518     case TEST_UNIT_READY:
 519         trace_scsi_test_unit_ready(d->id, lun, tag);
 520         break;
 521     case REPORT_LUNS:
 522         trace_scsi_report_luns(d->id, lun, tag);
 523         break;
 524     case REQUEST_SENSE:
 525         trace_scsi_request_sense(d->id, lun, tag);
 526         break;
 527     default:
 528         break;
 529     }
 530
 531     return req;
 532 }
 533
 534 uint8_t *scsi_req_get_buf(SCSIRequest *req)
 535 {
 536     return req->ops->get_buf(req);
 537 }
 538
 539 static void scsi_clear_unit_attention(SCSIRequest *req)
 540 {
 541     SCSISense *ua;
 542     if (req->dev->unit_attention.key != UNIT_ATTENTION &&
 543         req->bus->unit_attention.key != UNIT_ATTENTION) {
 544         return;
 545     }
 546
 547     /*
 548      * If an INQUIRY command enters the enabled command state,
 549      * the device server shall [not] clear any unit attention condition;
 550      * See also MMC-6, paragraphs 6.5 and 6.6.2.
 551      */
 552     if (req->cmd.buf[0] == INQUIRY ||
 553         req->cmd.buf[0] == GET_CONFIGURATION ||
 554         req->cmd.buf[0] == GET_EVENT_STATUS_NOTIFICATION) {
 555         return;
 556     }
 557
 558     if (req->dev->unit_attention.key == UNIT_ATTENTION) {
 559         ua = &req->dev->unit_attention;
 560     } else {
 561         ua = &req->bus->unit_attention;
 562     }
 563
 564     /*
 565      * If a REPORT LUNS command enters the enabled command state, [...]
 566      * the device server shall clear any pending unit attention condition
 567      * with an additional sense code of REPORTED LUNS DATA HAS CHANGED.
 568      */
 569     if (req->cmd.buf[0] == REPORT_LUNS &&
 570         !(ua->asc == SENSE_CODE(REPORTED_LUNS_CHANGED).asc &&
 571           ua->ascq == SENSE_CODE(REPORTED_LUNS_CHANGED).ascq)) {
 572         return;
 573     }
 574
 575     *ua = SENSE_CODE(NO_SENSE);
 576 }
 577
 578 int scsi_req_get_sense(SCSIRequest *req, uint8_t *buf, int len)
 579 {
 580     int ret;
 581
 582     assert(len >= 14);
 583     if (!req->sense_len) {
 584         return 0;
 585     }
 586
 587     ret = scsi_build_sense(req->sense, req->sense_len, buf, len, true);
 588
 589     /*
 590      * FIXME: clearing unit attention conditions upon autosense should be done
 591      * only if the UA_INTLCK_CTRL field in the Control mode page is set to 00b
 592      * (SAM-5, 5.14).
 593      *
 594      * We assume UA_INTLCK_CTRL to be 00b for HBAs that support autosense, and
 595      * 10b for HBAs that do not support it (do not call scsi_req_get_sense).
 596      * Here we handle unit attention clearing for UA_INTLCK_CTRL == 00b.
 597      */
 598     if (req->dev->sense_is_ua) {
 599         if (req->dev->info->unit_attention_reported) {
 600             req->dev->info->unit_attention_reported(req->dev);
 601         }
 602         req->dev->sense_len = 0;
 603         req->dev->sense_is_ua = false;
 604     }
 605     return ret;
 606 }
 607
 608 int scsi_device_get_sense(SCSIDevice *dev, uint8_t *buf, int len, bool fixed)
 609 {
 610     return scsi_build_sense(dev->sense, dev->sense_len, buf, len, fixed);
 611 }
 612
 613 void scsi_req_build_sense(SCSIRequest *req, SCSISense sense)
 614 {
 615     trace_scsi_req_build_sense(req->dev->id, req->lun, req->tag,
 616                                sense.key, sense.asc, sense.ascq);
 617     memset(req->sense, 0, 18);
 618     req->sense[0] = 0xf0;
 619     req->sense[2] = sense.key;
 620     req->sense[7] = 10;
 621     req->sense[12] = sense.asc;
 622     req->sense[13] = sense.ascq;
 623     req->sense_len = 18;
 624 }
 625
 626 int32_t scsi_req_enqueue(SCSIRequest *req)
 627 {
 628     int32_t rc;
 629
 630     assert(!req->enqueued);
 631     scsi_req_ref(req);
 632     req->enqueued = true;
 633     QTAILQ_INSERT_TAIL(&req->dev->requests, req, next);
 634
 635     scsi_req_ref(req);
 636     rc = req->ops->send_command(req, req->cmd.buf);
 637     scsi_req_unref(req);
 638     return rc;
 639 }
 640
 641 static void scsi_req_dequeue(SCSIRequest *req)
 642 {
 643     trace_scsi_req_dequeue(req->dev->id, req->lun, req->tag);
 644     req->retry = false;
 645     if (req->enqueued) {
 646         QTAILQ_REMOVE(&req->dev->requests, req, next);
 647         req->enqueued = false;
 648         scsi_req_unref(req);
 649     }
 650 }
 651
 652 static int scsi_req_length(SCSICommand *cmd, SCSIDevice *dev, uint8_t *buf)
 653 {
 654     switch (buf[0] >> 5) {
 655     case 0:
 656         cmd->xfer = buf[4];
 657         cmd->len = 6;
 658         /* length 0 means 256 blocks */
 659         if (cmd->xfer == 0) {
 660             cmd->xfer = 256;
 661         }
 662         break;
 663     case 1:
 664     case 2:
 665         cmd->xfer = lduw_be_p(&buf[7]);
 666         cmd->len = 10;
 667         break;
 668     case 4:
 669         cmd->xfer = ldl_be_p(&buf[10]);
 670         cmd->len = 16;
 671         break;
 672     case 5:
 673         cmd->xfer = ldl_be_p(&buf[6]);
 674         cmd->len = 12;
 675         break;
 676     default:
 677         return -1;
 678     }
 679
 680     switch (buf[0]) {
 681     case TEST_UNIT_READY:
 682     case REWIND:
 683     case START_STOP:
 684     case SEEK_6:
 685     case WRITE_FILEMARKS:
 686     case SPACE:
 687     case RESERVE:
 688     case RELEASE:
 689     case ERASE:
 690     case ALLOW_MEDIUM_REMOVAL:
 691     case VERIFY_10:
 692     case SEEK_10:
 693     case SYNCHRONIZE_CACHE:
 694     case LOCK_UNLOCK_CACHE:
 695     case LOAD_UNLOAD:
 696     case SET_CD_SPEED:
 697     case SET_LIMITS:
 698     case WRITE_LONG_10:
 699     case MOVE_MEDIUM:
 700     case UPDATE_BLOCK:
 701         cmd->xfer = 0;
 702         break;
 703     case MODE_SENSE:
 704         break;
 705     case WRITE_SAME_10:
 706         cmd->xfer = 1;
 707         break;
 708     case READ_CAPACITY_10:
 709         cmd->xfer = 8;
 710         break;
 711     case READ_BLOCK_LIMITS:
 712         cmd->xfer = 6;
 713         break;
 714     case READ_POSITION:
 715         cmd->xfer = 20;
 716         break;
 717     case SEND_VOLUME_TAG:
 718         cmd->xfer *= 40;
 719         break;
 720     case MEDIUM_SCAN:
 721         cmd->xfer *= 8;
 722         break;
 723     case WRITE_10:
 724     case WRITE_VERIFY_10:
 725     case WRITE_6:
 726     case WRITE_12:
 727     case WRITE_VERIFY_12:
 728     case WRITE_16:
 729     case WRITE_VERIFY_16:
 730         cmd->xfer *= dev->blocksize;
 731         break;
 732     case READ_10:
 733     case READ_6:
 734     case READ_REVERSE:
 735     case RECOVER_BUFFERED_DATA:
 736     case READ_12:
 737     case READ_16:
 738         cmd->xfer *= dev->blocksize;
 739         break;
 740     case INQUIRY:
 741         cmd->xfer = buf[4] | (buf[3] << 8);
 742         break;
 743     case MAINTENANCE_OUT:
 744     case MAINTENANCE_IN:
 745         if (dev->type == TYPE_ROM) {
 746             /* GPCMD_REPORT_KEY and GPCMD_SEND_KEY from multi media commands */
 747             cmd->xfer = buf[9] | (buf[8] << 8);
 748         }
 749         break;
 750     }
 751     return 0;
 752 }
 753
 754 static int scsi_req_stream_length(SCSICommand *cmd, SCSIDevice *dev, uint8_t *buf)
 755 {
 756     switch (buf[0]) {
 757     /* stream commands */
 758     case READ_6:
 759     case READ_REVERSE:
 760     case RECOVER_BUFFERED_DATA:
 761     case WRITE_6:
 762         cmd->len = 6;
 763         cmd->xfer = buf[4] | (buf[3] << 8) | (buf[2] << 16);
 764         if (buf[1] & 0x01) { /* fixed */
 765             cmd->xfer *= dev->blocksize;
 766         }
 767         break;
 768     case REWIND:
 769     case START_STOP:
 770         cmd->len = 6;
 771         cmd->xfer = 0;
 772         break;
 773     /* generic commands */
 774     default:
 775         return scsi_req_length(cmd, dev, buf);
 776     }
 777     return 0;
 778 }
 779
 780 static void scsi_cmd_xfer_mode(SCSICommand *cmd)
 781 {
 782     switch (cmd->buf[0]) {
 783     case WRITE_6:
 784     case WRITE_10:
 785     case WRITE_VERIFY_10:
 786     case WRITE_12:
 787     case WRITE_VERIFY_12:
 788     case WRITE_16:
 789     case WRITE_VERIFY_16:
 790     case COPY:
 791     case COPY_VERIFY:
 792     case COMPARE:
 793     case CHANGE_DEFINITION:
 794     case LOG_SELECT:
 795     case MODE_SELECT:
 796     case MODE_SELECT_10:
 797     case SEND_DIAGNOSTIC:
 798     case WRITE_BUFFER:
 799     case FORMAT_UNIT:
 800     case REASSIGN_BLOCKS:
 801     case SEARCH_EQUAL:
 802     case SEARCH_HIGH:
 803     case SEARCH_LOW:
 804     case UPDATE_BLOCK:
 805     case WRITE_LONG_10:
 806     case WRITE_SAME_10:
 807     case SEARCH_HIGH_12:
 808     case SEARCH_EQUAL_12:
 809     case SEARCH_LOW_12:
 810     case MEDIUM_SCAN:
 811     case SEND_VOLUME_TAG:
 812     case PERSISTENT_RESERVE_OUT:
 813     case MAINTENANCE_OUT:
 814         cmd->mode = SCSI_XFER_TO_DEV;
 815         break;
 816     default:
 817         if (cmd->xfer)
 818             cmd->mode = SCSI_XFER_FROM_DEV;
 819         else {
 820             cmd->mode = SCSI_XFER_NONE;
 821         }
 822         break;
 823     }
 824 }
 825
 826 static uint64_t scsi_cmd_lba(SCSICommand *cmd)
 827 {
 828     uint8_t *buf = cmd->buf;
 829     uint64_t lba;
 830
 831     switch (buf[0] >> 5) {
 832     case 0:
 833         lba = ldl_be_p(&buf[0]) & 0x1fffff;
 834         break;
 835     case 1:
 836     case 2:
 837     case 5:
 838         lba = ldl_be_p(&buf[2]);
 839         break;
 840     case 4:
 841         lba = ldq_be_p(&buf[2]);
 842         break;
 843     default:
 844         lba = -1;
 845
 846     }
 847     return lba;
 848 }
 849
 850 int scsi_req_parse(SCSICommand *cmd, SCSIDevice *dev, uint8_t *buf)
 851 {
 852     int rc;
 853
 854     if (dev->type == TYPE_TAPE) {
 855         rc = scsi_req_stream_length(cmd, dev, buf);
 856     } else {
 857         rc = scsi_req_length(cmd, dev, buf);
 858     }
 859     if (rc != 0)
 860         return rc;
 861
 862     memcpy(cmd->buf, buf, cmd->len);
 863     scsi_cmd_xfer_mode(cmd);
 864     cmd->lba = scsi_cmd_lba(cmd);
 865     return 0;
 866 }
 867
 868 /*
 869  * Predefined sense codes
 870  */
 871
 872 /* No sense data available */
 873 const struct SCSISense sense_code_NO_SENSE = {
 874     .key = NO_SENSE , .asc = 0x00 , .ascq = 0x00
 875 };
 876
 877 /* LUN not ready, Manual intervention required */
 878 const struct SCSISense sense_code_LUN_NOT_READY = {
 879     .key = NOT_READY, .asc = 0x04, .ascq = 0x03
 880 };
 881
 882 /* LUN not ready, Medium not present */
 883 const struct SCSISense sense_code_NO_MEDIUM = {
 884     .key = NOT_READY, .asc = 0x3a, .ascq = 0x00
 885 };
 886
 887 /* LUN not ready, medium removal prevented */
 888 const struct SCSISense sense_code_NOT_READY_REMOVAL_PREVENTED = {
 889     .key = NOT_READY, .asc = 0x53, .ascq = 0x00
 890 };
 891
 892 /* Hardware error, internal target failure */
 893 const struct SCSISense sense_code_TARGET_FAILURE = {
 894     .key = HARDWARE_ERROR, .asc = 0x44, .ascq = 0x00
 895 };
 896
 897 /* Illegal request, invalid command operation code */
 898 const struct SCSISense sense_code_INVALID_OPCODE = {
 899     .key = ILLEGAL_REQUEST, .asc = 0x20, .ascq = 0x00
 900 };
 901
 902 /* Illegal request, LBA out of range */
 903 const struct SCSISense sense_code_LBA_OUT_OF_RANGE = {
 904     .key = ILLEGAL_REQUEST, .asc = 0x21, .ascq = 0x00
 905 };
 906
 907 /* Illegal request, Invalid field in CDB */
 908 const struct SCSISense sense_code_INVALID_FIELD = {
 909     .key = ILLEGAL_REQUEST, .asc = 0x24, .ascq = 0x00
 910 };
 911
 912 /* Illegal request, LUN not supported */
 913 const struct SCSISense sense_code_LUN_NOT_SUPPORTED = {
 914     .key = ILLEGAL_REQUEST, .asc = 0x25, .ascq = 0x00
 915 };
 916
 917 /* Illegal request, Saving parameters not supported */
 918 const struct SCSISense sense_code_SAVING_PARAMS_NOT_SUPPORTED = {
 919     .key = ILLEGAL_REQUEST, .asc = 0x39, .ascq = 0x00
 920 };
 921
 922 /* Illegal request, Incompatible medium installed */
 923 const struct SCSISense sense_code_INCOMPATIBLE_FORMAT = {
 924     .key = ILLEGAL_REQUEST, .asc = 0x30, .ascq = 0x00
 925 };
 926
 927 /* Illegal request, medium removal prevented */
 928 const struct SCSISense sense_code_ILLEGAL_REQ_REMOVAL_PREVENTED = {
 929     .key = ILLEGAL_REQUEST, .asc = 0x53, .ascq = 0x00
 930 };
 931
 932 /* Command aborted, I/O process terminated */
 933 const struct SCSISense sense_code_IO_ERROR = {
 934     .key = ABORTED_COMMAND, .asc = 0x00, .ascq = 0x06
 935 };
 936
 937 /* Command aborted, I_T Nexus loss occurred */
 938 const struct SCSISense sense_code_I_T_NEXUS_LOSS = {
 939     .key = ABORTED_COMMAND, .asc = 0x29, .ascq = 0x07
 940 };
 941
 942 /* Command aborted, Logical Unit failure */
 943 const struct SCSISense sense_code_LUN_FAILURE = {
 944     .key = ABORTED_COMMAND, .asc = 0x3e, .ascq = 0x01
 945 };
 946
 947 /* Unit attention, Power on, reset or bus device reset occurred */
 948 const struct SCSISense sense_code_RESET = {
 949     .key = UNIT_ATTENTION, .asc = 0x29, .ascq = 0x00
 950 };
 951
 952 /* Unit attention, No medium */
 953 const struct SCSISense sense_code_UNIT_ATTENTION_NO_MEDIUM = {
 954     .key = UNIT_ATTENTION, .asc = 0x3a, .ascq = 0x00
 955 };
 956
 957 /* Unit attention, Medium may have changed */
 958 const struct SCSISense sense_code_MEDIUM_CHANGED = {
 959     .key = UNIT_ATTENTION, .asc = 0x28, .ascq = 0x00
 960 };
 961
 962 /* Unit attention, Reported LUNs data has changed */
 963 const struct SCSISense sense_code_REPORTED_LUNS_CHANGED = {
 964     .key = UNIT_ATTENTION, .asc = 0x3f, .ascq = 0x0e
 965 };
 966
 967 /* Unit attention, Device internal reset */
 968 const struct SCSISense sense_code_DEVICE_INTERNAL_RESET = {
 969     .key = UNIT_ATTENTION, .asc = 0x29, .ascq = 0x04
 970 };
 971
 972 /*
 973  * scsi_build_sense
 974  *
 975  * Convert between fixed and descriptor sense buffers
 976  */
 977 int scsi_build_sense(uint8_t *in_buf, int in_len,
 978                      uint8_t *buf, int len, bool fixed)
 979 {
 980     bool fixed_in;
 981     SCSISense sense;
 982     if (!fixed && len < 8) {
 983         return 0;
 984     }
 985
 986     if (in_len == 0) {
 987         sense.key = NO_SENSE;
 988         sense.asc = 0;
 989         sense.ascq = 0;
 990     } else {
 991         fixed_in = (in_buf[0] & 2) == 0;
 992
 993         if (fixed == fixed_in) {
 994             memcpy(buf, in_buf, MIN(len, in_len));
 995             return MIN(len, in_len);
 996         }
 997
 998         if (fixed_in) {
 999             sense.key = in_buf[2];
1000             sense.asc = in_buf[12];
1001             sense.ascq = in_buf[13];
1002         } else {
1003             sense.key = in_buf[1];
1004             sense.asc = in_buf[2];
1005             sense.ascq = in_buf[3];
1006         }
1007     }
1008
1009     memset(buf, 0, len);
1010     if (fixed) {
1011         /* Return fixed format sense buffer */
1012         buf[0] = 0xf0;
1013         buf[2] = sense.key;
1014         buf[7] = 10;
1015         buf[12] = sense.asc;
1016         buf[13] = sense.ascq;
1017         return MIN(len, 18);
1018     } else {
1019         /* Return descriptor format sense buffer */
1020         buf[0] = 0x72;
1021         buf[1] = sense.key;
1022         buf[2] = sense.asc;
1023         buf[3] = sense.ascq;
1024         return 8;
1025     }
1026 }
1027
1028 static const char *scsi_command_name(uint8_t cmd)
1029 {
1030     static const char *names[] = {
1031         [ TEST_UNIT_READY          ] = "TEST_UNIT_READY",
1032         [ REWIND                   ] = "REWIND",
1033         [ REQUEST_SENSE            ] = "REQUEST_SENSE",
1034         [ FORMAT_UNIT              ] = "FORMAT_UNIT",
1035         [ READ_BLOCK_LIMITS        ] = "READ_BLOCK_LIMITS",
1036         [ REASSIGN_BLOCKS          ] = "REASSIGN_BLOCKS",
1037         [ READ_6                   ] = "READ_6",
1038         [ WRITE_6                  ] = "WRITE_6",
1039         [ SEEK_6                   ] = "SEEK_6",
1040         [ READ_REVERSE             ] = "READ_REVERSE",
1041         [ WRITE_FILEMARKS          ] = "WRITE_FILEMARKS",
1042         [ SPACE                    ] = "SPACE",
1043         [ INQUIRY                  ] = "INQUIRY",
1044         [ RECOVER_BUFFERED_DATA    ] = "RECOVER_BUFFERED_DATA",
1045         [ MAINTENANCE_IN           ] = "MAINTENANCE_IN",
1046         [ MAINTENANCE_OUT          ] = "MAINTENANCE_OUT",
1047         [ MODE_SELECT              ] = "MODE_SELECT",
1048         [ RESERVE                  ] = "RESERVE",
1049         [ RELEASE                  ] = "RELEASE",
1050         [ COPY                     ] = "COPY",
1051         [ ERASE                    ] = "ERASE",
1052         [ MODE_SENSE               ] = "MODE_SENSE",
1053         [ START_STOP               ] = "START_STOP",
1054         [ RECEIVE_DIAGNOSTIC       ] = "RECEIVE_DIAGNOSTIC",
1055         [ SEND_DIAGNOSTIC          ] = "SEND_DIAGNOSTIC",
1056         [ ALLOW_MEDIUM_REMOVAL     ] = "ALLOW_MEDIUM_REMOVAL",
1057         [ READ_CAPACITY_10         ] = "READ_CAPACITY_10",
1058         [ READ_10                  ] = "READ_10",
1059         [ WRITE_10                 ] = "WRITE_10",
1060         [ SEEK_10                  ] = "SEEK_10",
1061         [ WRITE_VERIFY_10          ] = "WRITE_VERIFY_10",
1062         [ VERIFY_10                ] = "VERIFY_10",
1063         [ SEARCH_HIGH              ] = "SEARCH_HIGH",
1064         [ SEARCH_EQUAL             ] = "SEARCH_EQUAL",
1065         [ SEARCH_LOW               ] = "SEARCH_LOW",
1066         [ SET_LIMITS               ] = "SET_LIMITS",
1067         [ PRE_FETCH                ] = "PRE_FETCH",
1068         /* READ_POSITION and PRE_FETCH use the same operation code */
1069         [ SYNCHRONIZE_CACHE        ] = "SYNCHRONIZE_CACHE",
1070         [ LOCK_UNLOCK_CACHE        ] = "LOCK_UNLOCK_CACHE",
1071         [ READ_DEFECT_DATA         ] = "READ_DEFECT_DATA",
1072         [ MEDIUM_SCAN              ] = "MEDIUM_SCAN",
1073         [ COMPARE                  ] = "COMPARE",
1074         [ COPY_VERIFY              ] = "COPY_VERIFY",
1075         [ WRITE_BUFFER             ] = "WRITE_BUFFER",
1076         [ READ_BUFFER              ] = "READ_BUFFER",
1077         [ UPDATE_BLOCK             ] = "UPDATE_BLOCK",
1078         [ READ_LONG_10             ] = "READ_LONG_10",
1079         [ WRITE_LONG_10            ] = "WRITE_LONG_10",
1080         [ CHANGE_DEFINITION        ] = "CHANGE_DEFINITION",
1081         [ WRITE_SAME_10            ] = "WRITE_SAME_10",
1082         [ UNMAP                    ] = "UNMAP",
1083         [ READ_TOC                 ] = "READ_TOC",
1084         [ REPORT_DENSITY_SUPPORT   ] = "REPORT_DENSITY_SUPPORT",
1085         [ GET_CONFIGURATION        ] = "GET_CONFIGURATION",
1086         [ LOG_SELECT               ] = "LOG_SELECT",
1087         [ LOG_SENSE                ] = "LOG_SENSE",
1088         [ MODE_SELECT_10           ] = "MODE_SELECT_10",
1089         [ RESERVE_10               ] = "RESERVE_10",
1090         [ RELEASE_10               ] = "RELEASE_10",
1091         [ MODE_SENSE_10            ] = "MODE_SENSE_10",
1092         [ PERSISTENT_RESERVE_IN    ] = "PERSISTENT_RESERVE_IN",
1093         [ PERSISTENT_RESERVE_OUT   ] = "PERSISTENT_RESERVE_OUT",
1094         [ WRITE_FILEMARKS_16       ] = "WRITE_FILEMARKS_16",
1095         [ EXTENDED_COPY            ] = "EXTENDED_COPY",
1096         [ ATA_PASSTHROUGH          ] = "ATA_PASSTHROUGH",
1097         [ ACCESS_CONTROL_IN        ] = "ACCESS_CONTROL_IN",
1098         [ ACCESS_CONTROL_OUT       ] = "ACCESS_CONTROL_OUT",
1099         [ READ_16                  ] = "READ_16",
1100         [ COMPARE_AND_WRITE        ] = "COMPARE_AND_WRITE",
1101         [ WRITE_16                 ] = "WRITE_16",
1102         [ WRITE_VERIFY_16          ] = "WRITE_VERIFY_16",
1103         [ VERIFY_16                ] = "VERIFY_16",
1104         [ SYNCHRONIZE_CACHE_16     ] = "SYNCHRONIZE_CACHE_16",
1105         [ LOCATE_16                ] = "LOCATE_16",
1106         [ WRITE_SAME_16            ] = "WRITE_SAME_16",
1107         /* ERASE_16 and WRITE_SAME_16 use the same operation code */
1108         [ SERVICE_ACTION_IN_16     ] = "SERVICE_ACTION_IN_16",
1109         [ WRITE_LONG_16            ] = "WRITE_LONG_16",
1110         [ REPORT_LUNS              ] = "REPORT_LUNS",
1111         [ BLANK                    ] = "BLANK",
1112         [ MOVE_MEDIUM              ] = "MOVE_MEDIUM",
1113         [ LOAD_UNLOAD              ] = "LOAD_UNLOAD",
1114         [ READ_12                  ] = "READ_12",
1115         [ WRITE_12                 ] = "WRITE_12",
1116         [ SERVICE_ACTION_IN_12     ] = "SERVICE_ACTION_IN_12",
1117         [ WRITE_VERIFY_12          ] = "WRITE_VERIFY_12",
1118         [ VERIFY_12                ] = "VERIFY_12",
1119         [ SEARCH_HIGH_12           ] = "SEARCH_HIGH_12",
1120         [ SEARCH_EQUAL_12          ] = "SEARCH_EQUAL_12",
1121         [ SEARCH_LOW_12            ] = "SEARCH_LOW_12",
1122         [ READ_ELEMENT_STATUS      ] = "READ_ELEMENT_STATUS",
1123         [ SEND_VOLUME_TAG          ] = "SEND_VOLUME_TAG",
1124         [ READ_DEFECT_DATA_12      ] = "READ_DEFECT_DATA_12",
1125         [ SET_CD_SPEED             ] = "SET_CD_SPEED",
1126     };
1127
1128     if (cmd >= ARRAY_SIZE(names) || names[cmd] == NULL)
1129         return "*UNKNOWN*";
1130     return names[cmd];
1131 }
1132
1133 SCSIRequest *scsi_req_ref(SCSIRequest *req)
1134 {
1135     req->refcount++;
1136     return req;
1137 }
1138
1139 void scsi_req_unref(SCSIRequest *req)
1140 {
1141     if (--req->refcount == 0) {
1142         if (req->ops->free_req) {
1143             req->ops->free_req(req);
1144         }
1145         g_free(req);
1146     }
1147 }
1148
1149 /* Tell the device that we finished processing this chunk of I/O.  It
1150    will start the next chunk or complete the command.  */
1151 void scsi_req_continue(SCSIRequest *req)
1152 {
1153     trace_scsi_req_continue(req->dev->id, req->lun, req->tag);
1154     if (req->cmd.mode == SCSI_XFER_TO_DEV) {
1155         req->ops->write_data(req);
1156     } else {
1157         req->ops->read_data(req);
1158     }
1159 }
1160
1161 /* Called by the devices when data is ready for the HBA.  The HBA should
1162    start a DMA operation to read or fill the device's data buffer.
1163    Once it completes, calling scsi_req_continue will restart I/O.  */
1164 void scsi_req_data(SCSIRequest *req, int len)
1165 {
1166     if (req->io_canceled) {
1167         trace_scsi_req_data_canceled(req->dev->id, req->lun, req->tag, len);
1168     } else {
1169         trace_scsi_req_data(req->dev->id, req->lun, req->tag, len);
1170         req->bus->info->transfer_data(req, len);
1171     }
1172 }
1173
1174 void scsi_req_print(SCSIRequest *req)
1175 {
1176     FILE *fp = stderr;
1177     int i;
1178
1179     fprintf(fp, "[%s id=%d] %s",
1180             req->dev->qdev.parent_bus->name,
1181             req->dev->id,
1182             scsi_command_name(req->cmd.buf[0]));
1183     for (i = 1; i < req->cmd.len; i++) {
1184         fprintf(fp, " 0x%02x", req->cmd.buf[i]);
1185     }
1186     switch (req->cmd.mode) {
1187     case SCSI_XFER_NONE:
1188         fprintf(fp, " - none\n");
1189         break;
1190     case SCSI_XFER_FROM_DEV:
1191         fprintf(fp, " - from-dev len=%zd\n", req->cmd.xfer);
1192         break;
1193     case SCSI_XFER_TO_DEV:
1194         fprintf(fp, " - to-dev len=%zd\n", req->cmd.xfer);
1195         break;
1196     default:
1197         fprintf(fp, " - Oops\n");
1198         break;
1199     }
1200 }
1201
1202 void scsi_req_complete(SCSIRequest *req, int status)
1203 {
1204     assert(req->status == -1);
1205     req->status = status;
1206
1207     assert(req->sense_len < sizeof(req->sense));
1208     if (status == GOOD) {
1209         req->sense_len = 0;
1210     }
1211
1212     if (req->sense_len) {
1213         memcpy(req->dev->sense, req->sense, req->sense_len);
1214         req->dev->sense_len = req->sense_len;
1215         req->dev->sense_is_ua = (req->ops == &reqops_unit_attention);
1216     } else {
1217         req->dev->sense_len = 0;
1218         req->dev->sense_is_ua = false;
1219     }
1220
1221     /*
1222      * Unit attention state is now stored in the device's sense buffer
1223      * if the HBA didn't do autosense.  Clear the pending unit attention
1224      * flags.
1225      */
1226     scsi_clear_unit_attention(req);
1227
1228     scsi_req_ref(req);
1229     scsi_req_dequeue(req);
1230     req->bus->info->complete(req, req->status);
1231     scsi_req_unref(req);
1232 }
1233
1234 void scsi_req_cancel(SCSIRequest *req)
1235 {
1236     if (!req->enqueued) {
1237         return;
1238     }
1239     scsi_req_ref(req);
1240     scsi_req_dequeue(req);
1241     req->io_canceled = true;
1242     if (req->ops->cancel_io) {
1243         req->ops->cancel_io(req);
1244     }
1245     if (req->bus->info->cancel) {
1246         req->bus->info->cancel(req);
1247     }
1248     scsi_req_unref(req);
1249 }
1250
1251 void scsi_req_abort(SCSIRequest *req, int status)
1252 {
1253     if (!req->enqueued) {
1254         return;
1255     }
1256     scsi_req_ref(req);
1257     scsi_req_dequeue(req);
1258     req->io_canceled = true;
1259     if (req->ops->cancel_io) {
1260         req->ops->cancel_io(req);
1261     }
1262     scsi_req_complete(req, status);
1263     scsi_req_unref(req);
1264 }
1265
1266 void scsi_device_purge_requests(SCSIDevice *sdev, SCSISense sense)
1267 {
1268     SCSIRequest *req;
1269
1270     while (!QTAILQ_EMPTY(&sdev->requests)) {
1271         req = QTAILQ_FIRST(&sdev->requests);
1272         scsi_req_cancel(req);
1273     }
1274     sdev->unit_attention = sense;
1275 }
1276
1277 static char *scsibus_get_fw_dev_path(DeviceState *dev)
1278 {
1279     SCSIDevice *d = DO_UPCAST(SCSIDevice, qdev, dev);
1280     char path[100];
1281
1282     snprintf(path, sizeof(path), "%s@%d:%d:%d", qdev_fw_name(dev),
1283              d->channel, d->id, d->lun);
1284
1285     return strdup(path);
1286 }
1287
1288 SCSIDevice *scsi_device_find(SCSIBus *bus, int channel, int id, int lun)
1289 {
1290     DeviceState *qdev;
1291     SCSIDevice *target_dev = NULL;
1292
1293     QTAILQ_FOREACH_REVERSE(qdev, &bus->qbus.children, ChildrenHead, sibling) {
1294         SCSIDevice *dev = DO_UPCAST(SCSIDevice, qdev, qdev);
1295
1296         if (dev->channel == channel && dev->id == id) {
1297             if (dev->lun == lun) {
1298                 return dev;
1299             }
1300             target_dev = dev;
1301         }
1302     }
1303     return target_dev;
1304 }