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
  11 static struct BusInfo scsi_bus_info = {
  12     .name  = "SCSI",
  13     .size  = sizeof(SCSIBus),
  14     .get_fw_dev_path = scsibus_get_fw_dev_path,
  15     .props = (Property[]) {
  16         DEFINE_PROP_UINT32("scsi-id", SCSIDevice, id, -1),
  17         DEFINE_PROP_END_OF_LIST(),
  18     },
  19 };
  20 static int next_scsi_bus;
  21
  22 /* Create a scsi bus, and attach devices to it.  */
  23 void scsi_bus_new(SCSIBus *bus, DeviceState *host, int tcq, int ndev,
  24                   const SCSIBusOps *ops)
  25 {
  26     qbus_create_inplace(&bus->qbus, &scsi_bus_info, host, NULL);
  27     bus->busnr = next_scsi_bus++;
  28     bus->tcq = tcq;
  29     bus->ndev = ndev;
  30     bus->ops = ops;
  31     bus->qbus.allow_hotplug = 1;
  32 }
  33
  34 static int scsi_qdev_init(DeviceState *qdev, DeviceInfo *base)
  35 {
  36     SCSIDevice *dev = DO_UPCAST(SCSIDevice, qdev, qdev);
  37     SCSIDeviceInfo *info = DO_UPCAST(SCSIDeviceInfo, qdev, base);
  38     SCSIBus *bus = DO_UPCAST(SCSIBus, qbus, dev->qdev.parent_bus);
  39     int rc = -1;
  40
  41     if (dev->id == -1) {
  42         for (dev->id = 0; dev->id < bus->ndev; dev->id++) {
  43             if (bus->devs[dev->id] == NULL)
  44                 break;
  45         }
  46     }
  47     if (dev->id >= bus->ndev) {
  48         error_report("bad scsi device id: %d", dev->id);
  49         goto err;
  50     }
  51
  52     if (bus->devs[dev->id]) {
  53         qdev_free(&bus->devs[dev->id]->qdev);
  54     }
  55     bus->devs[dev->id] = dev;
  56
  57     dev->info = info;
  58     QTAILQ_INIT(&dev->requests);
  59     rc = dev->info->init(dev);
  60     if (rc != 0) {
  61         bus->devs[dev->id] = NULL;
  62     }
  63
  64 err:
  65     return rc;
  66 }
  67
  68 static int scsi_qdev_exit(DeviceState *qdev)
  69 {
  70     SCSIDevice *dev = DO_UPCAST(SCSIDevice, qdev, qdev);
  71     SCSIBus *bus = DO_UPCAST(SCSIBus, qbus, dev->qdev.parent_bus);
  72
  73     assert(bus->devs[dev->id] != NULL);
  74     if (bus->devs[dev->id]->info->destroy) {
  75         bus->devs[dev->id]->info->destroy(bus->devs[dev->id]);
  76     }
  77     bus->devs[dev->id] = NULL;
  78     return 0;
  79 }
  80
  81 void scsi_qdev_register(SCSIDeviceInfo *info)
  82 {
  83     info->qdev.bus_info = &scsi_bus_info;
  84     info->qdev.init     = scsi_qdev_init;
  85     info->qdev.unplug   = qdev_simple_unplug_cb;
  86     info->qdev.exit     = scsi_qdev_exit;
  87     qdev_register(&info->qdev);
  88 }
  89
  90 /* handle legacy '-drive if=scsi,...' cmd line args */
  91 SCSIDevice *scsi_bus_legacy_add_drive(SCSIBus *bus, BlockDriverState *bdrv,
  92                                       int unit, bool removable)
  93 {
  94     const char *driver;
  95     DeviceState *dev;
  96
  97     driver = bdrv_is_sg(bdrv) ? "scsi-generic" : "scsi-disk";
  98     dev = qdev_create(&bus->qbus, driver);
  99     qdev_prop_set_uint32(dev, "scsi-id", unit);
 100     if (qdev_prop_exists(dev, "removable")) {
 101         qdev_prop_set_bit(dev, "removable", removable);
 102     }
 103     if (qdev_prop_set_drive(dev, "drive", bdrv) < 0) {
 104         qdev_free(dev);
 105         return NULL;
 106     }
 107     if (qdev_init(dev) < 0)
 108         return NULL;
 109     return DO_UPCAST(SCSIDevice, qdev, dev);
 110 }
 111
 112 int scsi_bus_legacy_handle_cmdline(SCSIBus *bus)
 113 {
 114     Location loc;
 115     DriveInfo *dinfo;
 116     int res = 0, unit;
 117
 118     loc_push_none(&loc);
 119     for (unit = 0; unit < bus->ndev; unit++) {
 120         dinfo = drive_get(IF_SCSI, bus->busnr, unit);
 121         if (dinfo == NULL) {
 122             continue;
 123         }
 124         qemu_opts_loc_restore(dinfo->opts);
 125         if (!scsi_bus_legacy_add_drive(bus, dinfo->bdrv, unit, false)) {
 126             res = -1;
 127             break;
 128         }
 129     }
 130     loc_pop(&loc);
 131     return res;
 132 }
 133
 134 SCSIRequest *scsi_req_alloc(size_t size, SCSIDevice *d, uint32_t tag, uint32_t lun)
 135 {
 136     SCSIRequest *req;
 137
 138     req = qemu_mallocz(size);
 139     req->refcount = 1;
 140     req->bus = scsi_bus_from_device(d);
 141     req->dev = d;
 142     req->tag = tag;
 143     req->lun = lun;
 144     req->status = -1;
 145     trace_scsi_req_alloc(req->dev->id, req->lun, req->tag);
 146     return req;
 147 }
 148
 149 SCSIRequest *scsi_req_new(SCSIDevice *d, uint32_t tag, uint32_t lun)
 150 {
 151     return d->info->alloc_req(d, tag, lun);
 152 }
 153
 154 uint8_t *scsi_req_get_buf(SCSIRequest *req)
 155 {
 156     return req->dev->info->get_buf(req);
 157 }
 158
 159 int scsi_req_get_sense(SCSIRequest *req, uint8_t *buf, int len)
 160 {
 161     if (req->dev->info->get_sense) {
 162         return req->dev->info->get_sense(req, buf, len);
 163     } else {
 164         return 0;
 165     }
 166 }
 167
 168 int32_t scsi_req_enqueue(SCSIRequest *req, uint8_t *buf)
 169 {
 170     int32_t rc;
 171
 172     assert(!req->enqueued);
 173     scsi_req_ref(req);
 174     req->enqueued = true;
 175     QTAILQ_INSERT_TAIL(&req->dev->requests, req, next);
 176
 177     scsi_req_ref(req);
 178     rc = req->dev->info->send_command(req, buf);
 179     scsi_req_unref(req);
 180     return rc;
 181 }
 182
 183 static void scsi_req_dequeue(SCSIRequest *req)
 184 {
 185     trace_scsi_req_dequeue(req->dev->id, req->lun, req->tag);
 186     if (req->enqueued) {
 187         QTAILQ_REMOVE(&req->dev->requests, req, next);
 188         req->enqueued = false;
 189         scsi_req_unref(req);
 190     }
 191 }
 192
 193 static int scsi_req_length(SCSIRequest *req, uint8_t *cmd)
 194 {
 195     switch (cmd[0] >> 5) {
 196     case 0:
 197         req->cmd.xfer = cmd[4];
 198         req->cmd.len = 6;
 199         /* length 0 means 256 blocks */
 200         if (req->cmd.xfer == 0)
 201             req->cmd.xfer = 256;
 202         break;
 203     case 1:
 204     case 2:
 205         req->cmd.xfer = cmd[8] | (cmd[7] << 8);
 206         req->cmd.len = 10;
 207         break;
 208     case 4:
 209         req->cmd.xfer = cmd[13] | (cmd[12] << 8) | (cmd[11] << 16) | (cmd[10] << 24);
 210         req->cmd.len = 16;
 211         break;
 212     case 5:
 213         req->cmd.xfer = cmd[9] | (cmd[8] << 8) | (cmd[7] << 16) | (cmd[6] << 24);
 214         req->cmd.len = 12;
 215         break;
 216     default:
 217         trace_scsi_req_parse_bad(req->dev->id, req->lun, req->tag, cmd[0]);
 218         return -1;
 219     }
 220
 221     switch(cmd[0]) {
 222     case TEST_UNIT_READY:
 223     case REZERO_UNIT:
 224     case START_STOP:
 225     case SEEK_6:
 226     case WRITE_FILEMARKS:
 227     case SPACE:
 228     case RESERVE:
 229     case RELEASE:
 230     case ERASE:
 231     case ALLOW_MEDIUM_REMOVAL:
 232     case VERIFY:
 233     case SEEK_10:
 234     case SYNCHRONIZE_CACHE:
 235     case LOCK_UNLOCK_CACHE:
 236     case LOAD_UNLOAD:
 237     case SET_CD_SPEED:
 238     case SET_LIMITS:
 239     case WRITE_LONG:
 240     case MOVE_MEDIUM:
 241     case UPDATE_BLOCK:
 242         req->cmd.xfer = 0;
 243         break;
 244     case MODE_SENSE:
 245         break;
 246     case WRITE_SAME:
 247         req->cmd.xfer = 1;
 248         break;
 249     case READ_CAPACITY:
 250         req->cmd.xfer = 8;
 251         break;
 252     case READ_BLOCK_LIMITS:
 253         req->cmd.xfer = 6;
 254         break;
 255     case READ_POSITION:
 256         req->cmd.xfer = 20;
 257         break;
 258     case SEND_VOLUME_TAG:
 259         req->cmd.xfer *= 40;
 260         break;
 261     case MEDIUM_SCAN:
 262         req->cmd.xfer *= 8;
 263         break;
 264     case WRITE_10:
 265     case WRITE_VERIFY:
 266     case WRITE_6:
 267     case WRITE_12:
 268     case WRITE_VERIFY_12:
 269     case WRITE_16:
 270     case WRITE_VERIFY_16:
 271         req->cmd.xfer *= req->dev->blocksize;
 272         break;
 273     case READ_10:
 274     case READ_6:
 275     case READ_REVERSE:
 276     case RECOVER_BUFFERED_DATA:
 277     case READ_12:
 278     case READ_16:
 279         req->cmd.xfer *= req->dev->blocksize;
 280         break;
 281     case INQUIRY:
 282         req->cmd.xfer = cmd[4] | (cmd[3] << 8);
 283         break;
 284     case MAINTENANCE_OUT:
 285     case MAINTENANCE_IN:
 286         if (req->dev->type == TYPE_ROM) {
 287             /* GPCMD_REPORT_KEY and GPCMD_SEND_KEY from multi media commands */
 288             req->cmd.xfer = cmd[9] | (cmd[8] << 8);
 289         }
 290         break;
 291     }
 292     return 0;
 293 }
 294
 295 static int scsi_req_stream_length(SCSIRequest *req, uint8_t *cmd)
 296 {
 297     switch(cmd[0]) {
 298     /* stream commands */
 299     case READ_6:
 300     case READ_REVERSE:
 301     case RECOVER_BUFFERED_DATA:
 302     case WRITE_6:
 303         req->cmd.len = 6;
 304         req->cmd.xfer = cmd[4] | (cmd[3] << 8) | (cmd[2] << 16);
 305         if (cmd[1] & 0x01) /* fixed */
 306             req->cmd.xfer *= req->dev->blocksize;
 307         break;
 308     case REWIND:
 309     case START_STOP:
 310         req->cmd.len = 6;
 311         req->cmd.xfer = 0;
 312         break;
 313     /* generic commands */
 314     default:
 315         return scsi_req_length(req, cmd);
 316     }
 317     return 0;
 318 }
 319
 320 static void scsi_req_xfer_mode(SCSIRequest *req)
 321 {
 322     switch (req->cmd.buf[0]) {
 323     case WRITE_6:
 324     case WRITE_10:
 325     case WRITE_VERIFY:
 326     case WRITE_12:
 327     case WRITE_VERIFY_12:
 328     case WRITE_16:
 329     case WRITE_VERIFY_16:
 330     case COPY:
 331     case COPY_VERIFY:
 332     case COMPARE:
 333     case CHANGE_DEFINITION:
 334     case LOG_SELECT:
 335     case MODE_SELECT:
 336     case MODE_SELECT_10:
 337     case SEND_DIAGNOSTIC:
 338     case WRITE_BUFFER:
 339     case FORMAT_UNIT:
 340     case REASSIGN_BLOCKS:
 341     case SEARCH_EQUAL:
 342     case SEARCH_HIGH:
 343     case SEARCH_LOW:
 344     case UPDATE_BLOCK:
 345     case WRITE_LONG:
 346     case WRITE_SAME:
 347     case SEARCH_HIGH_12:
 348     case SEARCH_EQUAL_12:
 349     case SEARCH_LOW_12:
 350     case SET_WINDOW:
 351     case MEDIUM_SCAN:
 352     case SEND_VOLUME_TAG:
 353     case WRITE_LONG_2:
 354     case PERSISTENT_RESERVE_OUT:
 355     case MAINTENANCE_OUT:
 356         req->cmd.mode = SCSI_XFER_TO_DEV;
 357         break;
 358     default:
 359         if (req->cmd.xfer)
 360             req->cmd.mode = SCSI_XFER_FROM_DEV;
 361         else {
 362             req->cmd.mode = SCSI_XFER_NONE;
 363         }
 364         break;
 365     }
 366 }
 367
 368 static uint64_t scsi_req_lba(SCSIRequest *req)
 369 {
 370     uint8_t *buf = req->cmd.buf;
 371     uint64_t lba;
 372
 373     switch (buf[0] >> 5) {
 374     case 0:
 375         lba = (uint64_t) buf[3] | ((uint64_t) buf[2] << 8) |
 376               (((uint64_t) buf[1] & 0x1f) << 16);
 377         break;
 378     case 1:
 379     case 2:
 380         lba = (uint64_t) buf[5] | ((uint64_t) buf[4] << 8) |
 381               ((uint64_t) buf[3] << 16) | ((uint64_t) buf[2] << 24);
 382         break;
 383     case 4:
 384         lba = (uint64_t) buf[9] | ((uint64_t) buf[8] << 8) |
 385               ((uint64_t) buf[7] << 16) | ((uint64_t) buf[6] << 24) |
 386               ((uint64_t) buf[5] << 32) | ((uint64_t) buf[4] << 40) |
 387               ((uint64_t) buf[3] << 48) | ((uint64_t) buf[2] << 56);
 388         break;
 389     case 5:
 390         lba = (uint64_t) buf[5] | ((uint64_t) buf[4] << 8) |
 391               ((uint64_t) buf[3] << 16) | ((uint64_t) buf[2] << 24);
 392         break;
 393     default:
 394         lba = -1;
 395
 396     }
 397     return lba;
 398 }
 399
 400 int scsi_req_parse(SCSIRequest *req, uint8_t *buf)
 401 {
 402     int rc;
 403
 404     if (req->dev->type == TYPE_TAPE) {
 405         rc = scsi_req_stream_length(req, buf);
 406     } else {
 407         rc = scsi_req_length(req, buf);
 408     }
 409     if (rc != 0)
 410         return rc;
 411
 412     memcpy(req->cmd.buf, buf, req->cmd.len);
 413     scsi_req_xfer_mode(req);
 414     req->cmd.lba = scsi_req_lba(req);
 415     trace_scsi_req_parsed(req->dev->id, req->lun, req->tag, buf[0],
 416                           req->cmd.mode, req->cmd.xfer, req->cmd.lba);
 417     return 0;
 418 }
 419
 420 /*
 421  * Predefined sense codes
 422  */
 423
 424 /* No sense data available */
 425 const struct SCSISense sense_code_NO_SENSE = {
 426     .key = NO_SENSE , .asc = 0x00 , .ascq = 0x00
 427 };
 428
 429 /* LUN not ready, Manual intervention required */
 430 const struct SCSISense sense_code_LUN_NOT_READY = {
 431     .key = NOT_READY, .asc = 0x04, .ascq = 0x03
 432 };
 433
 434 /* LUN not ready, Medium not present */
 435 const struct SCSISense sense_code_NO_MEDIUM = {
 436     .key = NOT_READY, .asc = 0x3a, .ascq = 0x00
 437 };
 438
 439 /* Hardware error, internal target failure */
 440 const struct SCSISense sense_code_TARGET_FAILURE = {
 441     .key = HARDWARE_ERROR, .asc = 0x44, .ascq = 0x00
 442 };
 443
 444 /* Illegal request, invalid command operation code */
 445 const struct SCSISense sense_code_INVALID_OPCODE = {
 446     .key = ILLEGAL_REQUEST, .asc = 0x20, .ascq = 0x00
 447 };
 448
 449 /* Illegal request, LBA out of range */
 450 const struct SCSISense sense_code_LBA_OUT_OF_RANGE = {
 451     .key = ILLEGAL_REQUEST, .asc = 0x21, .ascq = 0x00
 452 };
 453
 454 /* Illegal request, Invalid field in CDB */
 455 const struct SCSISense sense_code_INVALID_FIELD = {
 456     .key = ILLEGAL_REQUEST, .asc = 0x24, .ascq = 0x00
 457 };
 458
 459 /* Illegal request, LUN not supported */
 460 const struct SCSISense sense_code_LUN_NOT_SUPPORTED = {
 461     .key = ILLEGAL_REQUEST, .asc = 0x25, .ascq = 0x00
 462 };
 463
 464 /* Command aborted, I/O process terminated */
 465 const struct SCSISense sense_code_IO_ERROR = {
 466     .key = ABORTED_COMMAND, .asc = 0x00, .ascq = 0x06
 467 };
 468
 469 /* Command aborted, I_T Nexus loss occurred */
 470 const struct SCSISense sense_code_I_T_NEXUS_LOSS = {
 471     .key = ABORTED_COMMAND, .asc = 0x29, .ascq = 0x07
 472 };
 473
 474 /* Command aborted, Logical Unit failure */
 475 const struct SCSISense sense_code_LUN_FAILURE = {
 476     .key = ABORTED_COMMAND, .asc = 0x3e, .ascq = 0x01
 477 };
 478
 479 /*
 480  * scsi_build_sense
 481  *
 482  * Build a sense buffer
 483  */
 484 int scsi_build_sense(SCSISense sense, uint8_t *buf, int len, int fixed)
 485 {
 486     if (!fixed && len < 8) {
 487         return 0;
 488     }
 489
 490     memset(buf, 0, len);
 491     if (fixed) {
 492         /* Return fixed format sense buffer */
 493         buf[0] = 0xf0;
 494         buf[2] = sense.key;
 495         buf[7] = 7;
 496         buf[12] = sense.asc;
 497         buf[13] = sense.ascq;
 498         return MIN(len, 18);
 499     } else {
 500         /* Return descriptor format sense buffer */
 501         buf[0] = 0x72;
 502         buf[1] = sense.key;
 503         buf[2] = sense.asc;
 504         buf[3] = sense.ascq;
 505         return 8;
 506     }
 507 }
 508
 509 static const char *scsi_command_name(uint8_t cmd)
 510 {
 511     static const char *names[] = {
 512         [ TEST_UNIT_READY          ] = "TEST_UNIT_READY",
 513         [ REZERO_UNIT              ] = "REZERO_UNIT",
 514         /* REWIND and REZERO_UNIT use the same operation code */
 515         [ REQUEST_SENSE            ] = "REQUEST_SENSE",
 516         [ FORMAT_UNIT              ] = "FORMAT_UNIT",
 517         [ READ_BLOCK_LIMITS        ] = "READ_BLOCK_LIMITS",
 518         [ REASSIGN_BLOCKS          ] = "REASSIGN_BLOCKS",
 519         [ READ_6                   ] = "READ_6",
 520         [ WRITE_6                  ] = "WRITE_6",
 521         [ SEEK_6                   ] = "SEEK_6",
 522         [ READ_REVERSE             ] = "READ_REVERSE",
 523         [ WRITE_FILEMARKS          ] = "WRITE_FILEMARKS",
 524         [ SPACE                    ] = "SPACE",
 525         [ INQUIRY                  ] = "INQUIRY",
 526         [ RECOVER_BUFFERED_DATA    ] = "RECOVER_BUFFERED_DATA",
 527         [ MAINTENANCE_IN           ] = "MAINTENANCE_IN",
 528         [ MAINTENANCE_OUT          ] = "MAINTENANCE_OUT",
 529         [ MODE_SELECT              ] = "MODE_SELECT",
 530         [ RESERVE                  ] = "RESERVE",
 531         [ RELEASE                  ] = "RELEASE",
 532         [ COPY                     ] = "COPY",
 533         [ ERASE                    ] = "ERASE",
 534         [ MODE_SENSE               ] = "MODE_SENSE",
 535         [ START_STOP               ] = "START_STOP",
 536         [ RECEIVE_DIAGNOSTIC       ] = "RECEIVE_DIAGNOSTIC",
 537         [ SEND_DIAGNOSTIC          ] = "SEND_DIAGNOSTIC",
 538         [ ALLOW_MEDIUM_REMOVAL     ] = "ALLOW_MEDIUM_REMOVAL",
 539
 540         [ SET_WINDOW               ] = "SET_WINDOW",
 541         [ READ_CAPACITY            ] = "READ_CAPACITY",
 542         [ READ_10                  ] = "READ_10",
 543         [ WRITE_10                 ] = "WRITE_10",
 544         [ SEEK_10                  ] = "SEEK_10",
 545         [ WRITE_VERIFY             ] = "WRITE_VERIFY",
 546         [ VERIFY                   ] = "VERIFY",
 547         [ SEARCH_HIGH              ] = "SEARCH_HIGH",
 548         [ SEARCH_EQUAL             ] = "SEARCH_EQUAL",
 549         [ SEARCH_LOW               ] = "SEARCH_LOW",
 550         [ SET_LIMITS               ] = "SET_LIMITS",
 551         [ PRE_FETCH                ] = "PRE_FETCH",
 552         /* READ_POSITION and PRE_FETCH use the same operation code */
 553         [ SYNCHRONIZE_CACHE        ] = "SYNCHRONIZE_CACHE",
 554         [ LOCK_UNLOCK_CACHE        ] = "LOCK_UNLOCK_CACHE",
 555         [ READ_DEFECT_DATA         ] = "READ_DEFECT_DATA",
 556         [ MEDIUM_SCAN              ] = "MEDIUM_SCAN",
 557         [ COMPARE                  ] = "COMPARE",
 558         [ COPY_VERIFY              ] = "COPY_VERIFY",
 559         [ WRITE_BUFFER             ] = "WRITE_BUFFER",
 560         [ READ_BUFFER              ] = "READ_BUFFER",
 561         [ UPDATE_BLOCK             ] = "UPDATE_BLOCK",
 562         [ READ_LONG                ] = "READ_LONG",
 563         [ WRITE_LONG               ] = "WRITE_LONG",
 564         [ CHANGE_DEFINITION        ] = "CHANGE_DEFINITION",
 565         [ WRITE_SAME               ] = "WRITE_SAME",
 566         [ READ_TOC                 ] = "READ_TOC",
 567         [ LOG_SELECT               ] = "LOG_SELECT",
 568         [ LOG_SENSE                ] = "LOG_SENSE",
 569         [ MODE_SELECT_10           ] = "MODE_SELECT_10",
 570         [ RESERVE_10               ] = "RESERVE_10",
 571         [ RELEASE_10               ] = "RELEASE_10",
 572         [ MODE_SENSE_10            ] = "MODE_SENSE_10",
 573         [ PERSISTENT_RESERVE_IN    ] = "PERSISTENT_RESERVE_IN",
 574         [ PERSISTENT_RESERVE_OUT   ] = "PERSISTENT_RESERVE_OUT",
 575         [ MOVE_MEDIUM              ] = "MOVE_MEDIUM",
 576         [ READ_12                  ] = "READ_12",
 577         [ WRITE_12                 ] = "WRITE_12",
 578         [ WRITE_VERIFY_12          ] = "WRITE_VERIFY_12",
 579         [ SEARCH_HIGH_12           ] = "SEARCH_HIGH_12",
 580         [ SEARCH_EQUAL_12          ] = "SEARCH_EQUAL_12",
 581         [ SEARCH_LOW_12            ] = "SEARCH_LOW_12",
 582         [ READ_ELEMENT_STATUS      ] = "READ_ELEMENT_STATUS",
 583         [ SEND_VOLUME_TAG          ] = "SEND_VOLUME_TAG",
 584         [ WRITE_LONG_2             ] = "WRITE_LONG_2",
 585
 586         [ REPORT_DENSITY_SUPPORT   ] = "REPORT_DENSITY_SUPPORT",
 587         [ GET_CONFIGURATION        ] = "GET_CONFIGURATION",
 588         [ READ_16                  ] = "READ_16",
 589         [ WRITE_16                 ] = "WRITE_16",
 590         [ WRITE_VERIFY_16          ] = "WRITE_VERIFY_16",
 591         [ SERVICE_ACTION_IN        ] = "SERVICE_ACTION_IN",
 592         [ REPORT_LUNS              ] = "REPORT_LUNS",
 593         [ LOAD_UNLOAD              ] = "LOAD_UNLOAD",
 594         [ SET_CD_SPEED             ] = "SET_CD_SPEED",
 595         [ BLANK                    ] = "BLANK",
 596     };
 597
 598     if (cmd >= ARRAY_SIZE(names) || names[cmd] == NULL)
 599         return "*UNKNOWN*";
 600     return names[cmd];
 601 }
 602
 603 SCSIRequest *scsi_req_ref(SCSIRequest *req)
 604 {
 605     req->refcount++;
 606     return req;
 607 }
 608
 609 void scsi_req_unref(SCSIRequest *req)
 610 {
 611     if (--req->refcount == 0) {
 612         if (req->dev->info->free_req) {
 613             req->dev->info->free_req(req);
 614         }
 615         qemu_free(req);
 616     }
 617 }
 618
 619 /* Tell the device that we finished processing this chunk of I/O.  It
 620    will start the next chunk or complete the command.  */
 621 void scsi_req_continue(SCSIRequest *req)
 622 {
 623     trace_scsi_req_continue(req->dev->id, req->lun, req->tag);
 624     if (req->cmd.mode == SCSI_XFER_TO_DEV) {
 625         req->dev->info->write_data(req);
 626     } else {
 627         req->dev->info->read_data(req);
 628     }
 629 }
 630
 631 /* Called by the devices when data is ready for the HBA.  The HBA should
 632    start a DMA operation to read or fill the device's data buffer.
 633    Once it completes, calling scsi_req_continue will restart I/O.  */
 634 void scsi_req_data(SCSIRequest *req, int len)
 635 {
 636     trace_scsi_req_data(req->dev->id, req->lun, req->tag, len);
 637     req->bus->ops->complete(req, SCSI_REASON_DATA, len);
 638 }
 639
 640 void scsi_req_print(SCSIRequest *req)
 641 {
 642     FILE *fp = stderr;
 643     int i;
 644
 645     fprintf(fp, "[%s id=%d] %s",
 646             req->dev->qdev.parent_bus->name,
 647             req->dev->id,
 648             scsi_command_name(req->cmd.buf[0]));
 649     for (i = 1; i < req->cmd.len; i++) {
 650         fprintf(fp, " 0x%02x", req->cmd.buf[i]);
 651     }
 652     switch (req->cmd.mode) {
 653     case SCSI_XFER_NONE:
 654         fprintf(fp, " - none\n");
 655         break;
 656     case SCSI_XFER_FROM_DEV:
 657         fprintf(fp, " - from-dev len=%zd\n", req->cmd.xfer);
 658         break;
 659     case SCSI_XFER_TO_DEV:
 660         fprintf(fp, " - to-dev len=%zd\n", req->cmd.xfer);
 661         break;
 662     default:
 663         fprintf(fp, " - Oops\n");
 664         break;
 665     }
 666 }
 667
 668 void scsi_req_complete(SCSIRequest *req)
 669 {
 670     assert(req->status != -1);
 671     scsi_req_ref(req);
 672     scsi_req_dequeue(req);
 673     req->bus->ops->complete(req, SCSI_REASON_DONE, req->status);
 674     scsi_req_unref(req);
 675 }
 676
 677 void scsi_req_cancel(SCSIRequest *req)
 678 {
 679     if (req->dev && req->dev->info->cancel_io) {
 680         req->dev->info->cancel_io(req);
 681     }
 682     scsi_req_ref(req);
 683     scsi_req_dequeue(req);
 684     if (req->bus->ops->cancel) {
 685         req->bus->ops->cancel(req);
 686     }
 687     scsi_req_unref(req);
 688 }
 689
 690 void scsi_req_abort(SCSIRequest *req, int status)
 691 {
 692     req->status = status;
 693     if (req->dev && req->dev->info->cancel_io) {
 694         req->dev->info->cancel_io(req);
 695     }
 696     scsi_req_complete(req);
 697 }
 698
 699 void scsi_device_purge_requests(SCSIDevice *sdev)
 700 {
 701     SCSIRequest *req;
 702
 703     while (!QTAILQ_EMPTY(&sdev->requests)) {
 704         req = QTAILQ_FIRST(&sdev->requests);
 705         scsi_req_cancel(req);
 706     }
 707 }
 708
 709 static char *scsibus_get_fw_dev_path(DeviceState *dev)
 710 {
 711     SCSIDevice *d = (SCSIDevice*)dev;
 712     SCSIBus *bus = scsi_bus_from_device(d);
 713     char path[100];
 714     int i;
 715
 716     for (i = 0; i < bus->ndev; i++) {
 717         if (bus->devs[i] == d) {
 718             break;
 719         }
 720     }
 721
 722     assert(i != bus->ndev);
 723
 724     snprintf(path, sizeof(path), "%s@%x", qdev_fw_name(dev), i);
 725
 726     return strdup(path);
 727 }