scsi/utils.c

   1 /*
   2  *  SCSI helpers
   3  *
   4  *  Copyright 2017 Red Hat, Inc.
   5  *
   6  *  Authors:
   7  *   Fam Zheng <famz@redhat.com>
   8  *   Paolo Bonzini <pbonzini@redhat.com>
   9  *
  10  * This program is free software; you can redistribute it and/or modify it
  11  * under the terms of the GNU General Public License as published by the Free
  12  * Software Foundation; either version 2 of the License, or (at your option)
  13  * any later version.
  14  */
  15
  16 #include "qemu/osdep.h"
  17 #include "scsi/constants.h"
  18 #include "scsi/utils.h"
  19 #include "qemu/bswap.h"
  20
  21 uint32_t scsi_data_cdb_xfer(uint8_t *buf)
  22 {
  23     if ((buf[0] >> 5) == 0 && buf[4] == 0) {
  24         return 256;
  25     } else {
  26         return scsi_cdb_xfer(buf);
  27     }
  28 }
  29
  30 uint32_t scsi_cdb_xfer(uint8_t *buf)
  31 {
  32     switch (buf[0] >> 5) {
  33     case 0:
  34         return buf[4];
  35         break;
  36     case 1:
  37     case 2:
  38         return lduw_be_p(&buf[7]);
  39         break;
  40     case 4:
  41         return ldl_be_p(&buf[10]) & 0xffffffffULL;
  42         break;
  43     case 5:
  44         return ldl_be_p(&buf[6]) & 0xffffffffULL;
  45         break;
  46     default:
  47         return -1;
  48     }
  49 }
  50
  51 uint64_t scsi_cmd_lba(SCSICommand *cmd)
  52 {
  53     uint8_t *buf = cmd->buf;
  54     uint64_t lba;
  55
  56     switch (buf[0] >> 5) {
  57     case 0:
  58         lba = ldl_be_p(&buf[0]) & 0x1fffff;
  59         break;
  60     case 1:
  61     case 2:
  62     case 5:
  63         lba = ldl_be_p(&buf[2]) & 0xffffffffULL;
  64         break;
  65     case 4:
  66         lba = ldq_be_p(&buf[2]);
  67         break;
  68     default:
  69         lba = -1;
  70
  71     }
  72     return lba;
  73 }
  74
  75 int scsi_cdb_length(uint8_t *buf)
  76 {
  77     int cdb_len;
  78
  79     switch (buf[0] >> 5) {
  80     case 0:
  81         cdb_len = 6;
  82         break;
  83     case 1:
  84     case 2:
  85         cdb_len = 10;
  86         break;
  87     case 4:
  88         cdb_len = 16;
  89         break;
  90     case 5:
  91         cdb_len = 12;
  92         break;
  93     default:
  94         cdb_len = -1;
  95     }
  96     return cdb_len;
  97 }
  98
  99 SCSISense scsi_parse_sense_buf(const uint8_t *in_buf, int in_len)
 100 {
 101     bool fixed_in;
 102     SCSISense sense;
 103
 104     assert(in_len > 0);
 105     fixed_in = (in_buf[0] & 2) == 0;
 106     if (fixed_in) {
 107         if (in_len < 14) {
 108             return SENSE_CODE(IO_ERROR);
 109         }
 110         sense.key = in_buf[2];
 111         sense.asc = in_buf[12];
 112         sense.ascq = in_buf[13];
 113     } else {
 114         if (in_len < 4) {
 115             return SENSE_CODE(IO_ERROR);
 116         }
 117         sense.key = in_buf[1];
 118         sense.asc = in_buf[2];
 119         sense.ascq = in_buf[3];
 120     }
 121
 122     return sense;
 123 }
 124
 125 int scsi_build_sense_buf(uint8_t *out_buf, size_t size, SCSISense sense,
 126                          bool fixed_sense)
 127 {
 128     int len;
 129     uint8_t buf[SCSI_SENSE_LEN] = { 0 };
 130
 131     if (fixed_sense) {
 132         buf[0] = 0x70;
 133         buf[2] = sense.key;
 134         buf[7] = 10;
 135         buf[12] = sense.asc;
 136         buf[13] = sense.ascq;
 137         len = 18;
 138     } else {
 139         buf[0] = 0x72;
 140         buf[1] = sense.key;
 141         buf[2] = sense.asc;
 142         buf[3] = sense.ascq;
 143         len = 8;
 144     }
 145     len = MIN(len, size);
 146     memcpy(out_buf, buf, len);
 147     return len;
 148 }
 149
 150 int scsi_build_sense(uint8_t *buf, SCSISense sense)
 151 {
 152     return scsi_build_sense_buf(buf, SCSI_SENSE_LEN, sense, true);
 153 }
 154
 155 /*
 156  * Predefined sense codes
 157  */
 158
 159 /* No sense data available */
 160 const struct SCSISense sense_code_NO_SENSE = {
 161     .key = NO_SENSE , .asc = 0x00 , .ascq = 0x00
 162 };
 163
 164 /* LUN not ready, Manual intervention required */
 165 const struct SCSISense sense_code_LUN_NOT_READY = {
 166     .key = NOT_READY, .asc = 0x04, .ascq = 0x03
 167 };
 168
 169 /* LUN not ready, Medium not present */
 170 const struct SCSISense sense_code_NO_MEDIUM = {
 171     .key = NOT_READY, .asc = 0x3a, .ascq = 0x00
 172 };
 173
 174 /* LUN not ready, medium removal prevented */
 175 const struct SCSISense sense_code_NOT_READY_REMOVAL_PREVENTED = {
 176     .key = NOT_READY, .asc = 0x53, .ascq = 0x02
 177 };
 178
 179 /* Hardware error, internal target failure */
 180 const struct SCSISense sense_code_TARGET_FAILURE = {
 181     .key = HARDWARE_ERROR, .asc = 0x44, .ascq = 0x00
 182 };
 183
 184 /* Illegal request, invalid command operation code */
 185 const struct SCSISense sense_code_INVALID_OPCODE = {
 186     .key = ILLEGAL_REQUEST, .asc = 0x20, .ascq = 0x00
 187 };
 188
 189 /* Illegal request, LBA out of range */
 190 const struct SCSISense sense_code_LBA_OUT_OF_RANGE = {
 191     .key = ILLEGAL_REQUEST, .asc = 0x21, .ascq = 0x00
 192 };
 193
 194 /* Illegal request, Invalid field in CDB */
 195 const struct SCSISense sense_code_INVALID_FIELD = {
 196     .key = ILLEGAL_REQUEST, .asc = 0x24, .ascq = 0x00
 197 };
 198
 199 /* Illegal request, Invalid field in parameter list */
 200 const struct SCSISense sense_code_INVALID_PARAM = {
 201     .key = ILLEGAL_REQUEST, .asc = 0x26, .ascq = 0x00
 202 };
 203
 204 /* Illegal request, Parameter list length error */
 205 const struct SCSISense sense_code_INVALID_PARAM_LEN = {
 206     .key = ILLEGAL_REQUEST, .asc = 0x1a, .ascq = 0x00
 207 };
 208
 209 /* Illegal request, LUN not supported */
 210 const struct SCSISense sense_code_LUN_NOT_SUPPORTED = {
 211     .key = ILLEGAL_REQUEST, .asc = 0x25, .ascq = 0x00
 212 };
 213
 214 /* Illegal request, Saving parameters not supported */
 215 const struct SCSISense sense_code_SAVING_PARAMS_NOT_SUPPORTED = {
 216     .key = ILLEGAL_REQUEST, .asc = 0x39, .ascq = 0x00
 217 };
 218
 219 /* Illegal request, Incompatible medium installed */
 220 const struct SCSISense sense_code_INCOMPATIBLE_FORMAT = {
 221     .key = ILLEGAL_REQUEST, .asc = 0x30, .ascq = 0x00
 222 };
 223
 224 /* Illegal request, medium removal prevented */
 225 const struct SCSISense sense_code_ILLEGAL_REQ_REMOVAL_PREVENTED = {
 226     .key = ILLEGAL_REQUEST, .asc = 0x53, .ascq = 0x02
 227 };
 228
 229 /* Illegal request, Invalid Transfer Tag */
 230 const struct SCSISense sense_code_INVALID_TAG = {
 231     .key = ILLEGAL_REQUEST, .asc = 0x4b, .ascq = 0x01
 232 };
 233
 234 /* Command aborted, I/O process terminated */
 235 const struct SCSISense sense_code_IO_ERROR = {
 236     .key = ABORTED_COMMAND, .asc = 0x00, .ascq = 0x06
 237 };
 238
 239 /* Command aborted, I_T Nexus loss occurred */
 240 const struct SCSISense sense_code_I_T_NEXUS_LOSS = {
 241     .key = ABORTED_COMMAND, .asc = 0x29, .ascq = 0x07
 242 };
 243
 244 /* Command aborted, Logical Unit failure */
 245 const struct SCSISense sense_code_LUN_FAILURE = {
 246     .key = ABORTED_COMMAND, .asc = 0x3e, .ascq = 0x01
 247 };
 248
 249 /* Command aborted, Overlapped Commands Attempted */
 250 const struct SCSISense sense_code_OVERLAPPED_COMMANDS = {
 251     .key = ABORTED_COMMAND, .asc = 0x4e, .ascq = 0x00
 252 };
 253
 254 /* Command aborted, LUN Communication Failure */
 255 const struct SCSISense sense_code_LUN_COMM_FAILURE = {
 256     .key = ABORTED_COMMAND, .asc = 0x08, .ascq = 0x00
 257 };
 258
 259 /* Medium Error, Unrecovered read error */
 260 const struct SCSISense sense_code_READ_ERROR = {
 261     .key = MEDIUM_ERROR, .asc = 0x11, .ascq = 0x00
 262 };
 263
 264 /* Not ready, Cause not reportable */
 265 const struct SCSISense sense_code_NOT_READY = {
 266     .key = NOT_READY, .asc = 0x04, .ascq = 0x00
 267 };
 268
 269 /* Unit attention, Capacity data has changed */
 270 const struct SCSISense sense_code_CAPACITY_CHANGED = {
 271     .key = UNIT_ATTENTION, .asc = 0x2a, .ascq = 0x09
 272 };
 273
 274 /* Unit attention, Power on, reset or bus device reset occurred */
 275 const struct SCSISense sense_code_RESET = {
 276     .key = UNIT_ATTENTION, .asc = 0x29, .ascq = 0x00
 277 };
 278
 279 /* Unit attention, SCSI bus reset */
 280 const struct SCSISense sense_code_SCSI_BUS_RESET = {
 281     .key = UNIT_ATTENTION, .asc = 0x29, .ascq = 0x02
 282 };
 283
 284 /* Unit attention, No medium */
 285 const struct SCSISense sense_code_UNIT_ATTENTION_NO_MEDIUM = {
 286     .key = UNIT_ATTENTION, .asc = 0x3a, .ascq = 0x00
 287 };
 288
 289 /* Unit attention, Medium may have changed */
 290 const struct SCSISense sense_code_MEDIUM_CHANGED = {
 291     .key = UNIT_ATTENTION, .asc = 0x28, .ascq = 0x00
 292 };
 293
 294 /* Unit attention, Reported LUNs data has changed */
 295 const struct SCSISense sense_code_REPORTED_LUNS_CHANGED = {
 296     .key = UNIT_ATTENTION, .asc = 0x3f, .ascq = 0x0e
 297 };
 298
 299 /* Unit attention, Device internal reset */
 300 const struct SCSISense sense_code_DEVICE_INTERNAL_RESET = {
 301     .key = UNIT_ATTENTION, .asc = 0x29, .ascq = 0x04
 302 };
 303
 304 /* Data Protection, Write Protected */
 305 const struct SCSISense sense_code_WRITE_PROTECTED = {
 306     .key = DATA_PROTECT, .asc = 0x27, .ascq = 0x00
 307 };
 308
 309 /* Data Protection, Space Allocation Failed Write Protect */
 310 const struct SCSISense sense_code_SPACE_ALLOC_FAILED = {
 311     .key = DATA_PROTECT, .asc = 0x27, .ascq = 0x07
 312 };
 313
 314 /*
 315  * scsi_convert_sense
 316  *
 317  * Convert between fixed and descriptor sense buffers
 318  */
 319 int scsi_convert_sense(uint8_t *in_buf, int in_len,
 320                        uint8_t *buf, int len, bool fixed)
 321 {
 322     SCSISense sense;
 323     bool fixed_in;
 324
 325     fixed_in = (in_buf[0] & 2) == 0;
 326     if (in_len && fixed == fixed_in) {
 327         memcpy(buf, in_buf, MIN(len, in_len));
 328         return MIN(len, in_len);
 329     }
 330
 331     if (in_len == 0) {
 332         sense = SENSE_CODE(NO_SENSE);
 333     } else {
 334         sense = scsi_parse_sense_buf(in_buf, in_len);
 335     }
 336     return scsi_build_sense_buf(buf, len, sense, fixed);
 337 }
 338
 339 int scsi_sense_to_errno(int key, int asc, int ascq)
 340 {
 341     switch (key) {
 342     case NO_SENSE:
 343     case RECOVERED_ERROR:
 344     case UNIT_ATTENTION:
 345         /* These sense keys are not errors */
 346         return 0;
 347     case ABORTED_COMMAND: /* COMMAND ABORTED */
 348         return ECANCELED;
 349     case NOT_READY:
 350     case ILLEGAL_REQUEST:
 351     case DATA_PROTECT:
 352         /* Parse ASCQ */
 353         break;
 354     default:
 355         return EIO;
 356     }
 357     switch ((asc << 8) | ascq) {
 358     case 0x1a00: /* PARAMETER LIST LENGTH ERROR */
 359     case 0x2000: /* INVALID OPERATION CODE */
 360     case 0x2400: /* INVALID FIELD IN CDB */
 361     case 0x2600: /* INVALID FIELD IN PARAMETER LIST */
 362         return EINVAL;
 363     case 0x2100: /* LBA OUT OF RANGE */
 364     case 0x2707: /* SPACE ALLOC FAILED */
 365         return ENOSPC;
 366     case 0x2500: /* LOGICAL UNIT NOT SUPPORTED */
 367         return ENOTSUP;
 368     case 0x3a00: /* MEDIUM NOT PRESENT */
 369     case 0x3a01: /* MEDIUM NOT PRESENT TRAY CLOSED */
 370     case 0x3a02: /* MEDIUM NOT PRESENT TRAY OPEN */
 371         return ENOMEDIUM;
 372     case 0x2700: /* WRITE PROTECTED */
 373         return EACCES;
 374     case 0x0401: /* NOT READY, IN PROGRESS OF BECOMING READY */
 375         return EAGAIN;
 376     case 0x0402: /* NOT READY, INITIALIZING COMMAND REQUIRED */
 377         return ENOTCONN;
 378     default:
 379         return EIO;
 380     }
 381 }
 382
 383 int scsi_sense_buf_to_errno(const uint8_t *in_buf, size_t in_len)
 384 {
 385     SCSISense sense;
 386     if (in_len < 1) {
 387         return EIO;
 388     }
 389
 390     sense = scsi_parse_sense_buf(in_buf, in_len);
 391     return scsi_sense_to_errno(sense.key, sense.asc, sense.ascq);
 392 }
 393
 394 const char *scsi_command_name(uint8_t cmd)
 395 {
 396     static const char *names[] = {
 397         [ TEST_UNIT_READY          ] = "TEST_UNIT_READY",
 398         [ REWIND                   ] = "REWIND",
 399         [ REQUEST_SENSE            ] = "REQUEST_SENSE",
 400         [ FORMAT_UNIT              ] = "FORMAT_UNIT",
 401         [ READ_BLOCK_LIMITS        ] = "READ_BLOCK_LIMITS",
 402         [ REASSIGN_BLOCKS          ] = "REASSIGN_BLOCKS/INITIALIZE ELEMENT STATUS",
 403         /* LOAD_UNLOAD and INITIALIZE_ELEMENT_STATUS use the same operation code */
 404         [ READ_6                   ] = "READ_6",
 405         [ WRITE_6                  ] = "WRITE_6",
 406         [ SET_CAPACITY             ] = "SET_CAPACITY",
 407         [ READ_REVERSE             ] = "READ_REVERSE",
 408         [ WRITE_FILEMARKS          ] = "WRITE_FILEMARKS",
 409         [ SPACE                    ] = "SPACE",
 410         [ INQUIRY                  ] = "INQUIRY",
 411         [ RECOVER_BUFFERED_DATA    ] = "RECOVER_BUFFERED_DATA",
 412         [ MAINTENANCE_IN           ] = "MAINTENANCE_IN",
 413         [ MAINTENANCE_OUT          ] = "MAINTENANCE_OUT",
 414         [ MODE_SELECT              ] = "MODE_SELECT",
 415         [ RESERVE                  ] = "RESERVE",
 416         [ RELEASE                  ] = "RELEASE",
 417         [ COPY                     ] = "COPY",
 418         [ ERASE                    ] = "ERASE",
 419         [ MODE_SENSE               ] = "MODE_SENSE",
 420         [ START_STOP               ] = "START_STOP/LOAD_UNLOAD",
 421         /* LOAD_UNLOAD and START_STOP use the same operation code */
 422         [ RECEIVE_DIAGNOSTIC       ] = "RECEIVE_DIAGNOSTIC",
 423         [ SEND_DIAGNOSTIC          ] = "SEND_DIAGNOSTIC",
 424         [ ALLOW_MEDIUM_REMOVAL     ] = "ALLOW_MEDIUM_REMOVAL",
 425         [ READ_CAPACITY_10         ] = "READ_CAPACITY_10",
 426         [ READ_10                  ] = "READ_10",
 427         [ WRITE_10                 ] = "WRITE_10",
 428         [ SEEK_10                  ] = "SEEK_10/POSITION_TO_ELEMENT",
 429         /* SEEK_10 and POSITION_TO_ELEMENT use the same operation code */
 430         [ WRITE_VERIFY_10          ] = "WRITE_VERIFY_10",
 431         [ VERIFY_10                ] = "VERIFY_10",
 432         [ SEARCH_HIGH              ] = "SEARCH_HIGH",
 433         [ SEARCH_EQUAL             ] = "SEARCH_EQUAL",
 434         [ SEARCH_LOW               ] = "SEARCH_LOW",
 435         [ SET_LIMITS               ] = "SET_LIMITS",
 436         [ PRE_FETCH                ] = "PRE_FETCH/READ_POSITION",
 437         /* READ_POSITION and PRE_FETCH use the same operation code */
 438         [ SYNCHRONIZE_CACHE        ] = "SYNCHRONIZE_CACHE",
 439         [ LOCK_UNLOCK_CACHE        ] = "LOCK_UNLOCK_CACHE",
 440         [ READ_DEFECT_DATA         ] = "READ_DEFECT_DATA/INITIALIZE_ELEMENT_STATUS_WITH_RANGE",
 441         /* READ_DEFECT_DATA and INITIALIZE_ELEMENT_STATUS_WITH_RANGE use the same operation code */
 442         [ MEDIUM_SCAN              ] = "MEDIUM_SCAN",
 443         [ COMPARE                  ] = "COMPARE",
 444         [ COPY_VERIFY              ] = "COPY_VERIFY",
 445         [ WRITE_BUFFER             ] = "WRITE_BUFFER",
 446         [ READ_BUFFER              ] = "READ_BUFFER",
 447         [ UPDATE_BLOCK             ] = "UPDATE_BLOCK",
 448         [ READ_LONG_10             ] = "READ_LONG_10",
 449         [ WRITE_LONG_10            ] = "WRITE_LONG_10",
 450         [ CHANGE_DEFINITION        ] = "CHANGE_DEFINITION",
 451         [ WRITE_SAME_10            ] = "WRITE_SAME_10",
 452         [ UNMAP                    ] = "UNMAP",
 453         [ READ_TOC                 ] = "READ_TOC",
 454         [ REPORT_DENSITY_SUPPORT   ] = "REPORT_DENSITY_SUPPORT",
 455         [ SANITIZE                 ] = "SANITIZE",
 456         [ GET_CONFIGURATION        ] = "GET_CONFIGURATION",
 457         [ LOG_SELECT               ] = "LOG_SELECT",
 458         [ LOG_SENSE                ] = "LOG_SENSE",
 459         [ MODE_SELECT_10           ] = "MODE_SELECT_10",
 460         [ RESERVE_10               ] = "RESERVE_10",
 461         [ RELEASE_10               ] = "RELEASE_10",
 462         [ MODE_SENSE_10            ] = "MODE_SENSE_10",
 463         [ PERSISTENT_RESERVE_IN    ] = "PERSISTENT_RESERVE_IN",
 464         [ PERSISTENT_RESERVE_OUT   ] = "PERSISTENT_RESERVE_OUT",
 465         [ WRITE_FILEMARKS_16       ] = "WRITE_FILEMARKS_16",
 466         [ EXTENDED_COPY            ] = "EXTENDED_COPY",
 467         [ ATA_PASSTHROUGH_16       ] = "ATA_PASSTHROUGH_16",
 468         [ ACCESS_CONTROL_IN        ] = "ACCESS_CONTROL_IN",
 469         [ ACCESS_CONTROL_OUT       ] = "ACCESS_CONTROL_OUT",
 470         [ READ_16                  ] = "READ_16",
 471         [ COMPARE_AND_WRITE        ] = "COMPARE_AND_WRITE",
 472         [ WRITE_16                 ] = "WRITE_16",
 473         [ WRITE_VERIFY_16          ] = "WRITE_VERIFY_16",
 474         [ VERIFY_16                ] = "VERIFY_16",
 475         [ PRE_FETCH_16             ] = "PRE_FETCH_16",
 476         [ SYNCHRONIZE_CACHE_16     ] = "SPACE_16/SYNCHRONIZE_CACHE_16",
 477         /* SPACE_16 and SYNCHRONIZE_CACHE_16 use the same operation code */
 478         [ LOCATE_16                ] = "LOCATE_16",
 479         [ WRITE_SAME_16            ] = "ERASE_16/WRITE_SAME_16",
 480         /* ERASE_16 and WRITE_SAME_16 use the same operation code */
 481         [ SERVICE_ACTION_IN_16     ] = "SERVICE_ACTION_IN_16",
 482         [ WRITE_LONG_16            ] = "WRITE_LONG_16",
 483         [ REPORT_LUNS              ] = "REPORT_LUNS",
 484         [ ATA_PASSTHROUGH_12       ] = "BLANK/ATA_PASSTHROUGH_12",
 485         [ MOVE_MEDIUM              ] = "MOVE_MEDIUM",
 486         [ EXCHANGE_MEDIUM          ] = "EXCHANGE MEDIUM",
 487         [ READ_12                  ] = "READ_12",
 488         [ WRITE_12                 ] = "WRITE_12",
 489         [ ERASE_12                 ] = "ERASE_12/GET_PERFORMANCE",
 490         /* ERASE_12 and GET_PERFORMANCE use the same operation code */
 491         [ SERVICE_ACTION_IN_12     ] = "SERVICE_ACTION_IN_12",
 492         [ WRITE_VERIFY_12          ] = "WRITE_VERIFY_12",
 493         [ VERIFY_12                ] = "VERIFY_12",
 494         [ SEARCH_HIGH_12           ] = "SEARCH_HIGH_12",
 495         [ SEARCH_EQUAL_12          ] = "SEARCH_EQUAL_12",
 496         [ SEARCH_LOW_12            ] = "SEARCH_LOW_12",
 497         [ READ_ELEMENT_STATUS      ] = "READ_ELEMENT_STATUS",
 498         [ SEND_VOLUME_TAG          ] = "SEND_VOLUME_TAG/SET_STREAMING",
 499         /* SEND_VOLUME_TAG and SET_STREAMING use the same operation code */
 500         [ READ_CD                  ] = "READ_CD",
 501         [ READ_DEFECT_DATA_12      ] = "READ_DEFECT_DATA_12",
 502         [ READ_DVD_STRUCTURE       ] = "READ_DVD_STRUCTURE",
 503         [ RESERVE_TRACK            ] = "RESERVE_TRACK",
 504         [ SEND_CUE_SHEET           ] = "SEND_CUE_SHEET",
 505         [ SEND_DVD_STRUCTURE       ] = "SEND_DVD_STRUCTURE",
 506         [ SET_CD_SPEED             ] = "SET_CD_SPEED",
 507         [ SET_READ_AHEAD           ] = "SET_READ_AHEAD",
 508         [ ALLOW_OVERWRITE          ] = "ALLOW_OVERWRITE",
 509         [ MECHANISM_STATUS         ] = "MECHANISM_STATUS",
 510         [ GET_EVENT_STATUS_NOTIFICATION ] = "GET_EVENT_STATUS_NOTIFICATION",
 511         [ READ_DISC_INFORMATION    ] = "READ_DISC_INFORMATION",
 512     };
 513
 514     if (cmd >= ARRAY_SIZE(names) || names[cmd] == NULL) {
 515         return "*UNKNOWN*";
 516     }
 517     return names[cmd];
 518 }
 519
 520 #ifdef CONFIG_LINUX
 521 int sg_io_sense_from_errno(int errno_value, struct sg_io_hdr *io_hdr,
 522                            SCSISense *sense)
 523 {
 524     if (errno_value != 0) {
 525         switch (errno_value) {
 526         case EDOM:
 527             return TASK_SET_FULL;
 528         case ENOMEM:
 529             *sense = SENSE_CODE(TARGET_FAILURE);
 530             return CHECK_CONDITION;
 531         default:
 532             *sense = SENSE_CODE(IO_ERROR);
 533             return CHECK_CONDITION;
 534         }
 535     } else {
 536         if (io_hdr->host_status == SG_ERR_DID_NO_CONNECT ||
 537             io_hdr->host_status == SG_ERR_DID_BUS_BUSY ||
 538             io_hdr->host_status == SG_ERR_DID_TIME_OUT ||
 539             (io_hdr->driver_status & SG_ERR_DRIVER_TIMEOUT)) {
 540             return BUSY;
 541         } else if (io_hdr->host_status) {
 542             *sense = SENSE_CODE(I_T_NEXUS_LOSS);
 543             return CHECK_CONDITION;
 544         } else if (io_hdr->status) {
 545             return io_hdr->status;
 546         } else if (io_hdr->driver_status & SG_ERR_DRIVER_SENSE) {
 547             return CHECK_CONDITION;
 548         } else {
 549             return GOOD;
 550         }
 551     }
 552 }
 553 #endif