1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * scsi_error.c Copyright (C) 1997 Eric Youngdale 4 * 5 * SCSI error/timeout handling 6 * Initial versions: Eric Youngdale. Based upon conversations with 7 * Leonard Zubkoff and David Miller at Linux Expo, 8 * ideas originating from all over the place. 9 * 10 * Restructured scsi_unjam_host and associated functions. 11 * September 04, 2002 Mike Anderson (andmike@us.ibm.com) 12 * 13 * Forward port of Russell King's (rmk@arm.linux.org.uk) changes and 14 * minor cleanups. 15 * September 30, 2002 Mike Anderson (andmike@us.ibm.com) 16 */ 17 18 #include <linux/module.h> 19 #include <linux/sched.h> 20 #include <linux/gfp.h> 21 #include <linux/timer.h> 22 #include <linux/string.h> 23 #include <linux/kernel.h> 24 #include <linux/freezer.h> 25 #include <linux/kthread.h> 26 #include <linux/interrupt.h> 27 #include <linux/blkdev.h> 28 #include <linux/delay.h> 29 #include <linux/jiffies.h> 30 31 #include <scsi/scsi.h> 32 #include <scsi/scsi_cmnd.h> 33 #include <scsi/scsi_dbg.h> 34 #include <scsi/scsi_device.h> 35 #include <scsi/scsi_driver.h> 36 #include <scsi/scsi_eh.h> 37 #include <scsi/scsi_common.h> 38 #include <scsi/scsi_transport.h> 39 #include <scsi/scsi_host.h> 40 #include <scsi/scsi_ioctl.h> 41 #include <scsi/scsi_dh.h> 42 #include <scsi/scsi_devinfo.h> 43 #include <scsi/sg.h> 44 45 #include "scsi_priv.h" 46 #include "scsi_logging.h" 47 #include "scsi_transport_api.h" 48 49 #include <trace/events/scsi.h> 50 51 #include <linux/unaligned.h> 52 53 /* 54 * These should *probably* be handled by the host itself. 55 * Since it is allowed to sleep, it probably should. 56 */ 57 #define BUS_RESET_SETTLE_TIME (10) 58 #define HOST_RESET_SETTLE_TIME (10) 59 60 static int scsi_eh_try_stu(struct scsi_cmnd *scmd); 61 static enum scsi_disposition scsi_try_to_abort_cmd(const struct scsi_host_template *, 62 struct scsi_cmnd *); 63 64 void scsi_eh_wakeup(struct Scsi_Host *shost, unsigned int busy) 65 { 66 lockdep_assert_held(shost->host_lock); 67 68 if (busy == shost->host_failed) { 69 trace_scsi_eh_wakeup(shost); 70 wake_up_process(shost->ehandler); 71 SCSI_LOG_ERROR_RECOVERY(5, shost_printk(KERN_INFO, shost, 72 "Waking error handler thread\n")); 73 } 74 } 75 76 /** 77 * scsi_schedule_eh - schedule EH for SCSI host 78 * @shost: SCSI host to invoke error handling on. 79 * 80 * Schedule SCSI EH without scmd. 81 */ 82 void scsi_schedule_eh(struct Scsi_Host *shost) 83 { 84 unsigned long flags; 85 86 spin_lock_irqsave(shost->host_lock, flags); 87 88 if (scsi_host_set_state(shost, SHOST_RECOVERY) == 0 || 89 scsi_host_set_state(shost, SHOST_CANCEL_RECOVERY) == 0) { 90 shost->host_eh_scheduled++; 91 scsi_eh_wakeup(shost, scsi_host_busy(shost)); 92 } 93 94 spin_unlock_irqrestore(shost->host_lock, flags); 95 } 96 EXPORT_SYMBOL_GPL(scsi_schedule_eh); 97 98 static int scsi_host_eh_past_deadline(struct Scsi_Host *shost) 99 { 100 if (!shost->last_reset || shost->eh_deadline == -1) 101 return 0; 102 103 /* 104 * 32bit accesses are guaranteed to be atomic 105 * (on all supported architectures), so instead 106 * of using a spinlock we can as well double check 107 * if eh_deadline has been set to 'off' during the 108 * time_before call. 109 */ 110 if (time_before(jiffies, shost->last_reset + shost->eh_deadline) && 111 shost->eh_deadline > -1) 112 return 0; 113 114 return 1; 115 } 116 117 static bool scsi_cmd_retry_allowed(struct scsi_cmnd *cmd) 118 { 119 if (cmd->allowed == SCSI_CMD_RETRIES_NO_LIMIT) 120 return true; 121 122 return ++cmd->retries <= cmd->allowed; 123 } 124 125 static bool scsi_eh_should_retry_cmd(struct scsi_cmnd *cmd) 126 { 127 struct scsi_device *sdev = cmd->device; 128 struct Scsi_Host *host = sdev->host; 129 130 if (host->hostt->eh_should_retry_cmd) 131 return host->hostt->eh_should_retry_cmd(cmd); 132 133 return true; 134 } 135 136 /** 137 * scmd_eh_abort_handler - Handle command aborts 138 * @work: command to be aborted. 139 * 140 * Note: this function must be called only for a command that has timed out. 141 * Because the block layer marks a request as complete before it calls 142 * scsi_timeout(), a .scsi_done() call from the LLD for a command that has 143 * timed out do not have any effect. Hence it is safe to call 144 * scsi_finish_command() from this function. 145 */ 146 void 147 scmd_eh_abort_handler(struct work_struct *work) 148 { 149 struct scsi_cmnd *scmd = 150 container_of(work, struct scsi_cmnd, abort_work.work); 151 struct scsi_device *sdev = scmd->device; 152 struct Scsi_Host *shost = sdev->host; 153 enum scsi_disposition rtn; 154 unsigned long flags; 155 156 if (scsi_host_eh_past_deadline(shost)) { 157 SCSI_LOG_ERROR_RECOVERY(3, 158 scmd_printk(KERN_INFO, scmd, 159 "eh timeout, not aborting\n")); 160 goto out; 161 } 162 163 SCSI_LOG_ERROR_RECOVERY(3, 164 scmd_printk(KERN_INFO, scmd, 165 "aborting command\n")); 166 rtn = scsi_try_to_abort_cmd(shost->hostt, scmd); 167 if (rtn != SUCCESS) { 168 SCSI_LOG_ERROR_RECOVERY(3, 169 scmd_printk(KERN_INFO, scmd, 170 "cmd abort %s\n", 171 (rtn == FAST_IO_FAIL) ? 172 "not send" : "failed")); 173 goto out; 174 } 175 set_host_byte(scmd, DID_TIME_OUT); 176 if (scsi_host_eh_past_deadline(shost)) { 177 SCSI_LOG_ERROR_RECOVERY(3, 178 scmd_printk(KERN_INFO, scmd, 179 "eh timeout, not retrying " 180 "aborted command\n")); 181 goto out; 182 } 183 184 spin_lock_irqsave(shost->host_lock, flags); 185 list_del_init(&scmd->eh_entry); 186 187 /* 188 * If the abort succeeds, and there is no further 189 * EH action, clear the ->last_reset time. 190 */ 191 if (list_empty(&shost->eh_abort_list) && 192 list_empty(&shost->eh_cmd_q)) 193 if (shost->eh_deadline != -1) 194 shost->last_reset = 0; 195 196 spin_unlock_irqrestore(shost->host_lock, flags); 197 198 if (!scsi_noretry_cmd(scmd) && 199 scsi_cmd_retry_allowed(scmd) && 200 scsi_eh_should_retry_cmd(scmd)) { 201 SCSI_LOG_ERROR_RECOVERY(3, 202 scmd_printk(KERN_WARNING, scmd, 203 "retry aborted command\n")); 204 scsi_queue_insert(scmd, SCSI_MLQUEUE_EH_RETRY); 205 } else { 206 SCSI_LOG_ERROR_RECOVERY(3, 207 scmd_printk(KERN_WARNING, scmd, 208 "finish aborted command\n")); 209 scsi_finish_command(scmd); 210 } 211 return; 212 213 out: 214 spin_lock_irqsave(shost->host_lock, flags); 215 list_del_init(&scmd->eh_entry); 216 spin_unlock_irqrestore(shost->host_lock, flags); 217 218 scsi_eh_scmd_add(scmd); 219 } 220 221 /** 222 * scsi_abort_command - schedule a command abort 223 * @scmd: scmd to abort. 224 * 225 * We only need to abort commands after a command timeout 226 */ 227 static int 228 scsi_abort_command(struct scsi_cmnd *scmd) 229 { 230 struct scsi_device *sdev = scmd->device; 231 struct Scsi_Host *shost = sdev->host; 232 unsigned long flags; 233 234 if (!shost->hostt->eh_abort_handler) { 235 /* No abort handler, fail command directly */ 236 return FAILED; 237 } 238 239 if (scmd->eh_eflags & SCSI_EH_ABORT_SCHEDULED) { 240 /* 241 * Retry after abort failed, escalate to next level. 242 */ 243 SCSI_LOG_ERROR_RECOVERY(3, 244 scmd_printk(KERN_INFO, scmd, 245 "previous abort failed\n")); 246 BUG_ON(delayed_work_pending(&scmd->abort_work)); 247 return FAILED; 248 } 249 250 spin_lock_irqsave(shost->host_lock, flags); 251 if (shost->eh_deadline != -1 && !shost->last_reset) 252 shost->last_reset = jiffies; 253 BUG_ON(!list_empty(&scmd->eh_entry)); 254 list_add_tail(&scmd->eh_entry, &shost->eh_abort_list); 255 spin_unlock_irqrestore(shost->host_lock, flags); 256 257 scmd->eh_eflags |= SCSI_EH_ABORT_SCHEDULED; 258 SCSI_LOG_ERROR_RECOVERY(3, 259 scmd_printk(KERN_INFO, scmd, "abort scheduled\n")); 260 queue_delayed_work(shost->tmf_work_q, &scmd->abort_work, HZ / 100); 261 return SUCCESS; 262 } 263 264 /** 265 * scsi_eh_reset - call into ->eh_action to reset internal counters 266 * @scmd: scmd to run eh on. 267 * 268 * The scsi driver might be carrying internal state about the 269 * devices, so we need to call into the driver to reset the 270 * internal state once the error handler is started. 271 */ 272 static void scsi_eh_reset(struct scsi_cmnd *scmd) 273 { 274 if (!blk_rq_is_passthrough(scsi_cmd_to_rq(scmd))) { 275 struct scsi_driver *sdrv = scsi_cmd_to_driver(scmd); 276 if (sdrv->eh_reset) 277 sdrv->eh_reset(scmd); 278 } 279 } 280 281 static void scsi_eh_inc_host_failed(struct rcu_head *head) 282 { 283 struct scsi_cmnd *scmd = container_of(head, typeof(*scmd), rcu); 284 struct Scsi_Host *shost = scmd->device->host; 285 unsigned int busy = scsi_host_busy(shost); 286 unsigned long flags; 287 288 spin_lock_irqsave(shost->host_lock, flags); 289 shost->host_failed++; 290 scsi_eh_wakeup(shost, busy); 291 spin_unlock_irqrestore(shost->host_lock, flags); 292 } 293 294 /** 295 * scsi_eh_scmd_add - add scsi cmd to error handling. 296 * @scmd: scmd to run eh on. 297 */ 298 void scsi_eh_scmd_add(struct scsi_cmnd *scmd) 299 { 300 struct Scsi_Host *shost = scmd->device->host; 301 unsigned long flags; 302 int ret; 303 304 WARN_ON_ONCE(!shost->ehandler); 305 WARN_ON_ONCE(!test_bit(SCMD_STATE_INFLIGHT, &scmd->state)); 306 307 spin_lock_irqsave(shost->host_lock, flags); 308 if (scsi_host_set_state(shost, SHOST_RECOVERY)) { 309 ret = scsi_host_set_state(shost, SHOST_CANCEL_RECOVERY); 310 WARN_ON_ONCE(ret); 311 } 312 if (shost->eh_deadline != -1 && !shost->last_reset) 313 shost->last_reset = jiffies; 314 315 scsi_eh_reset(scmd); 316 list_add_tail(&scmd->eh_entry, &shost->eh_cmd_q); 317 spin_unlock_irqrestore(shost->host_lock, flags); 318 /* 319 * Ensure that all tasks observe the host state change before the 320 * host_failed change. 321 */ 322 call_rcu_hurry(&scmd->rcu, scsi_eh_inc_host_failed); 323 } 324 325 /** 326 * scsi_timeout - Timeout function for normal scsi commands. 327 * @req: request that is timing out. 328 * 329 * Notes: 330 * We do not need to lock this. There is the potential for a race 331 * only in that the normal completion handling might run, but if the 332 * normal completion function determines that the timer has already 333 * fired, then it mustn't do anything. 334 */ 335 enum blk_eh_timer_return scsi_timeout(struct request *req) 336 { 337 struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(req); 338 struct Scsi_Host *host = scmd->device->host; 339 340 trace_scsi_dispatch_cmd_timeout(scmd); 341 scsi_log_completion(scmd, TIMEOUT_ERROR); 342 343 atomic_inc(&scmd->device->iotmo_cnt); 344 if (host->eh_deadline != -1 && !host->last_reset) 345 host->last_reset = jiffies; 346 347 if (host->hostt->eh_timed_out) { 348 switch (host->hostt->eh_timed_out(scmd)) { 349 case SCSI_EH_DONE: 350 return BLK_EH_DONE; 351 case SCSI_EH_RESET_TIMER: 352 return BLK_EH_RESET_TIMER; 353 case SCSI_EH_NOT_HANDLED: 354 break; 355 } 356 } 357 358 /* 359 * If scsi_done() has already set SCMD_STATE_COMPLETE, do not modify 360 * *scmd. 361 */ 362 if (test_and_set_bit(SCMD_STATE_COMPLETE, &scmd->state)) 363 return BLK_EH_DONE; 364 atomic_inc(&scmd->device->iodone_cnt); 365 if (scsi_abort_command(scmd) != SUCCESS) { 366 set_host_byte(scmd, DID_TIME_OUT); 367 scsi_eh_scmd_add(scmd); 368 } 369 370 return BLK_EH_DONE; 371 } 372 373 /** 374 * scsi_block_when_processing_errors - Prevent cmds from being queued. 375 * @sdev: Device on which we are performing recovery. 376 * 377 * Description: 378 * We block until the host is out of error recovery, and then check to 379 * see whether the host or the device is offline. 380 * 381 * Return value: 382 * 0 when dev was taken offline by error recovery. 1 OK to proceed. 383 */ 384 int scsi_block_when_processing_errors(struct scsi_device *sdev) 385 { 386 int online; 387 388 wait_event(sdev->host->host_wait, !scsi_host_in_recovery(sdev->host)); 389 390 online = scsi_device_online(sdev); 391 392 return online; 393 } 394 EXPORT_SYMBOL(scsi_block_when_processing_errors); 395 396 #ifdef CONFIG_SCSI_LOGGING 397 /** 398 * scsi_eh_prt_fail_stats - Log info on failures. 399 * @shost: scsi host being recovered. 400 * @work_q: Queue of scsi cmds to process. 401 */ 402 static inline void scsi_eh_prt_fail_stats(struct Scsi_Host *shost, 403 struct list_head *work_q) 404 { 405 struct scsi_cmnd *scmd; 406 struct scsi_device *sdev; 407 int total_failures = 0; 408 int cmd_failed = 0; 409 int cmd_cancel = 0; 410 int devices_failed = 0; 411 412 shost_for_each_device(sdev, shost) { 413 list_for_each_entry(scmd, work_q, eh_entry) { 414 if (scmd->device == sdev) { 415 ++total_failures; 416 if (scmd->eh_eflags & SCSI_EH_ABORT_SCHEDULED) 417 ++cmd_cancel; 418 else 419 ++cmd_failed; 420 } 421 } 422 423 if (cmd_cancel || cmd_failed) { 424 SCSI_LOG_ERROR_RECOVERY(3, 425 shost_printk(KERN_INFO, shost, 426 "%s: cmds failed: %d, cancel: %d\n", 427 __func__, cmd_failed, 428 cmd_cancel)); 429 cmd_cancel = 0; 430 cmd_failed = 0; 431 ++devices_failed; 432 } 433 } 434 435 SCSI_LOG_ERROR_RECOVERY(2, shost_printk(KERN_INFO, shost, 436 "Total of %d commands on %d" 437 " devices require eh work\n", 438 total_failures, devices_failed)); 439 } 440 #endif 441 442 /** 443 * scsi_report_lun_change - Set flag on all *other* devices on the same target 444 * to indicate that a UNIT ATTENTION is expected. 445 * @sdev: Device reporting the UNIT ATTENTION 446 */ 447 static void scsi_report_lun_change(struct scsi_device *sdev) 448 { 449 sdev->sdev_target->expecting_lun_change = 1; 450 } 451 452 /** 453 * scsi_report_sense - Examine scsi sense information and log messages for 454 * certain conditions, also issue uevents for some of them. 455 * @sdev: Device reporting the sense code 456 * @sshdr: sshdr to be examined 457 */ 458 static void scsi_report_sense(struct scsi_device *sdev, 459 struct scsi_sense_hdr *sshdr) 460 { 461 enum scsi_device_event evt_type = SDEV_EVT_MAXBITS; /* i.e. none */ 462 463 if (sshdr->sense_key == UNIT_ATTENTION) { 464 if (sshdr->asc == 0x3f && sshdr->ascq == 0x03) { 465 evt_type = SDEV_EVT_INQUIRY_CHANGE_REPORTED; 466 sdev_printk(KERN_WARNING, sdev, 467 "Inquiry data has changed"); 468 } else if (sshdr->asc == 0x3f && sshdr->ascq == 0x0e) { 469 evt_type = SDEV_EVT_LUN_CHANGE_REPORTED; 470 scsi_report_lun_change(sdev); 471 sdev_printk(KERN_WARNING, sdev, 472 "LUN assignments on this target have " 473 "changed. The Linux SCSI layer does not " 474 "automatically remap LUN assignments.\n"); 475 } else if (sshdr->asc == 0x3f) 476 sdev_printk(KERN_WARNING, sdev, 477 "Operating parameters on this target have " 478 "changed. The Linux SCSI layer does not " 479 "automatically adjust these parameters.\n"); 480 481 if (sshdr->asc == 0x38 && sshdr->ascq == 0x07) { 482 evt_type = SDEV_EVT_SOFT_THRESHOLD_REACHED_REPORTED; 483 sdev_printk(KERN_WARNING, sdev, 484 "Warning! Received an indication that the " 485 "LUN reached a thin provisioning soft " 486 "threshold.\n"); 487 } 488 489 if (sshdr->asc == 0x29) { 490 evt_type = SDEV_EVT_POWER_ON_RESET_OCCURRED; 491 /* 492 * Do not print message if it is an expected side-effect 493 * of runtime PM. 494 */ 495 if (!sdev->silence_suspend) 496 sdev_printk(KERN_WARNING, sdev, 497 "Power-on or device reset occurred\n"); 498 } 499 500 if (sshdr->asc == 0x2a && sshdr->ascq == 0x01) { 501 evt_type = SDEV_EVT_MODE_PARAMETER_CHANGE_REPORTED; 502 sdev_printk(KERN_WARNING, sdev, 503 "Mode parameters changed"); 504 } else if (sshdr->asc == 0x2a && sshdr->ascq == 0x06) { 505 evt_type = SDEV_EVT_ALUA_STATE_CHANGE_REPORTED; 506 sdev_printk(KERN_WARNING, sdev, 507 "Asymmetric access state changed"); 508 } else if (sshdr->asc == 0x2a && sshdr->ascq == 0x09) { 509 evt_type = SDEV_EVT_CAPACITY_CHANGE_REPORTED; 510 sdev_printk(KERN_WARNING, sdev, 511 "Capacity data has changed"); 512 } else if (sshdr->asc == 0x2a) 513 sdev_printk(KERN_WARNING, sdev, 514 "Parameters changed"); 515 } 516 517 if (evt_type != SDEV_EVT_MAXBITS) { 518 set_bit(evt_type, sdev->pending_events); 519 schedule_work(&sdev->event_work); 520 } 521 } 522 523 static inline void set_scsi_ml_byte(struct scsi_cmnd *cmd, u8 status) 524 { 525 cmd->result = (cmd->result & 0xffff00ff) | (status << 8); 526 } 527 528 /** 529 * scsi_check_sense - Examine scsi cmd sense 530 * @scmd: Cmd to have sense checked. 531 * 532 * Return value: 533 * SUCCESS or FAILED or NEEDS_RETRY or ADD_TO_MLQUEUE 534 * 535 * Notes: 536 * When a deferred error is detected the current command has 537 * not been executed and needs retrying. 538 */ 539 enum scsi_disposition scsi_check_sense(struct scsi_cmnd *scmd) 540 { 541 struct request *req = scsi_cmd_to_rq(scmd); 542 struct scsi_device *sdev = scmd->device; 543 struct scsi_sense_hdr sshdr; 544 545 if (! scsi_command_normalize_sense(scmd, &sshdr)) 546 return FAILED; /* no valid sense data */ 547 548 scsi_report_sense(sdev, &sshdr); 549 550 if (sshdr.sense_key == UNIT_ATTENTION) { 551 /* 552 * Increment the counters for Power on/Reset or New Media so 553 * that all ULDs interested in these can see that those have 554 * happened, even if someone else gets the sense data. 555 */ 556 if (sshdr.asc == 0x28) 557 scmd->device->ua_new_media_ctr++; 558 else if (sshdr.asc == 0x29) 559 scmd->device->ua_por_ctr++; 560 } 561 562 if (scsi_sense_is_deferred(&sshdr)) 563 return NEEDS_RETRY; 564 565 if (sdev->handler && sdev->handler->check_sense) { 566 enum scsi_disposition rc; 567 568 rc = sdev->handler->check_sense(sdev, &sshdr); 569 if (rc != SCSI_RETURN_NOT_HANDLED) 570 return rc; 571 /* handler does not care. Drop down to default handling */ 572 } 573 574 if (scmd->cmnd[0] == TEST_UNIT_READY && 575 scmd->submitter != SUBMITTED_BY_SCSI_ERROR_HANDLER) 576 /* 577 * nasty: for mid-layer issued TURs, we need to return the 578 * actual sense data without any recovery attempt. For eh 579 * issued ones, we need to try to recover and interpret 580 */ 581 return SUCCESS; 582 583 /* 584 * Previous logic looked for FILEMARK, EOM or ILI which are 585 * mainly associated with tapes and returned SUCCESS. 586 */ 587 if (sshdr.response_code == 0x70) { 588 /* fixed format */ 589 if (scmd->sense_buffer[2] & 0xe0) 590 return SUCCESS; 591 } else { 592 /* 593 * descriptor format: look for "stream commands sense data 594 * descriptor" (see SSC-3). Assume single sense data 595 * descriptor. Ignore ILI from SBC-2 READ LONG and WRITE LONG. 596 */ 597 if ((sshdr.additional_length > 3) && 598 (scmd->sense_buffer[8] == 0x4) && 599 (scmd->sense_buffer[11] & 0xe0)) 600 return SUCCESS; 601 } 602 603 switch (sshdr.sense_key) { 604 case NO_SENSE: 605 return SUCCESS; 606 case RECOVERED_ERROR: 607 return /* soft_error */ SUCCESS; 608 609 case ABORTED_COMMAND: 610 if (sshdr.asc == 0x10) /* DIF */ 611 return SUCCESS; 612 613 /* 614 * Check aborts due to command duration limit policy: 615 * ABORTED COMMAND additional sense code with the 616 * COMMAND TIMEOUT BEFORE PROCESSING or 617 * COMMAND TIMEOUT DURING PROCESSING or 618 * COMMAND TIMEOUT DURING PROCESSING DUE TO ERROR RECOVERY 619 * additional sense code qualifiers. 620 */ 621 if (sshdr.asc == 0x2e && 622 sshdr.ascq >= 0x01 && sshdr.ascq <= 0x03) { 623 set_scsi_ml_byte(scmd, SCSIML_STAT_DL_TIMEOUT); 624 req->cmd_flags |= REQ_FAILFAST_DEV; 625 req->rq_flags |= RQF_QUIET; 626 return SUCCESS; 627 } 628 629 if (sshdr.asc == 0x44 && sdev->sdev_bflags & BLIST_RETRY_ITF) 630 return ADD_TO_MLQUEUE; 631 if (sshdr.asc == 0xc1 && sshdr.ascq == 0x01 && 632 sdev->sdev_bflags & BLIST_RETRY_ASC_C1) 633 return ADD_TO_MLQUEUE; 634 635 return NEEDS_RETRY; 636 case NOT_READY: 637 case UNIT_ATTENTION: 638 /* 639 * if we are expecting a cc/ua because of a bus reset that we 640 * performed, treat this just as a retry. otherwise this is 641 * information that we should pass up to the upper-level driver 642 * so that we can deal with it there. 643 */ 644 if (scmd->device->expecting_cc_ua) { 645 /* 646 * Because some device does not queue unit 647 * attentions correctly, we carefully check 648 * additional sense code and qualifier so as 649 * not to squash media change unit attention. 650 */ 651 if (sshdr.asc != 0x28 || sshdr.ascq != 0x00) { 652 scmd->device->expecting_cc_ua = 0; 653 return NEEDS_RETRY; 654 } 655 } 656 /* 657 * we might also expect a cc/ua if another LUN on the target 658 * reported a UA with an ASC/ASCQ of 3F 0E - 659 * REPORTED LUNS DATA HAS CHANGED. 660 */ 661 if (scmd->device->sdev_target->expecting_lun_change && 662 sshdr.asc == 0x3f && sshdr.ascq == 0x0e) 663 return NEEDS_RETRY; 664 /* 665 * if the device is in the process of becoming ready, we 666 * should retry. 667 */ 668 if ((sshdr.asc == 0x04) && (sshdr.ascq == 0x01)) 669 return NEEDS_RETRY; 670 /* 671 * if the device is not started, we need to wake 672 * the error handler to start the motor 673 */ 674 if (scmd->device->allow_restart && 675 (sshdr.asc == 0x04) && (sshdr.ascq == 0x02)) 676 return FAILED; 677 /* 678 * Pass the UA upwards for a determination in the completion 679 * functions. 680 */ 681 return SUCCESS; 682 683 /* these are not supported */ 684 case DATA_PROTECT: 685 if (sshdr.asc == 0x27 && sshdr.ascq == 0x07) { 686 /* Thin provisioning hard threshold reached */ 687 set_scsi_ml_byte(scmd, SCSIML_STAT_NOSPC); 688 return SUCCESS; 689 } 690 fallthrough; 691 case COPY_ABORTED: 692 case VOLUME_OVERFLOW: 693 case MISCOMPARE: 694 case BLANK_CHECK: 695 set_scsi_ml_byte(scmd, SCSIML_STAT_TGT_FAILURE); 696 return SUCCESS; 697 698 case MEDIUM_ERROR: 699 if (sshdr.asc == 0x11 || /* UNRECOVERED READ ERR */ 700 sshdr.asc == 0x13 || /* AMNF DATA FIELD */ 701 sshdr.asc == 0x14) { /* RECORD NOT FOUND */ 702 set_scsi_ml_byte(scmd, SCSIML_STAT_MED_ERROR); 703 return SUCCESS; 704 } 705 return NEEDS_RETRY; 706 707 case HARDWARE_ERROR: 708 if (scmd->device->retry_hwerror) 709 return ADD_TO_MLQUEUE; 710 else 711 set_scsi_ml_byte(scmd, SCSIML_STAT_TGT_FAILURE); 712 fallthrough; 713 714 case ILLEGAL_REQUEST: 715 if (sshdr.asc == 0x20 || /* Invalid command operation code */ 716 sshdr.asc == 0x21 || /* Logical block address out of range */ 717 sshdr.asc == 0x22 || /* Invalid function */ 718 sshdr.asc == 0x24 || /* Invalid field in cdb */ 719 sshdr.asc == 0x26 || /* Parameter value invalid */ 720 sshdr.asc == 0x27) { /* Write protected */ 721 set_scsi_ml_byte(scmd, SCSIML_STAT_TGT_FAILURE); 722 } 723 return SUCCESS; 724 725 case COMPLETED: 726 /* 727 * A command using command duration limits (CDL) with a 728 * descriptor set with policy 0xD may be completed with success 729 * and the sense data DATA CURRENTLY UNAVAILABLE, indicating 730 * that the command was in fact aborted because it exceeded its 731 * duration limit. Never retry these commands. 732 */ 733 if (sshdr.asc == 0x55 && sshdr.ascq == 0x0a) { 734 set_scsi_ml_byte(scmd, SCSIML_STAT_DL_TIMEOUT); 735 req->cmd_flags |= REQ_FAILFAST_DEV; 736 req->rq_flags |= RQF_QUIET; 737 } 738 return SUCCESS; 739 740 default: 741 return SUCCESS; 742 } 743 } 744 EXPORT_SYMBOL_GPL(scsi_check_sense); 745 746 static void scsi_handle_queue_ramp_up(struct scsi_device *sdev) 747 { 748 const struct scsi_host_template *sht = sdev->host->hostt; 749 struct scsi_device *tmp_sdev; 750 751 if (!sht->track_queue_depth || 752 sdev->queue_depth >= sdev->max_queue_depth) 753 return; 754 755 if (time_before(jiffies, 756 sdev->last_queue_ramp_up + sdev->queue_ramp_up_period)) 757 return; 758 759 if (time_before(jiffies, 760 sdev->last_queue_full_time + sdev->queue_ramp_up_period)) 761 return; 762 763 /* 764 * Walk all devices of a target and do 765 * ramp up on them. 766 */ 767 shost_for_each_device(tmp_sdev, sdev->host) { 768 if (tmp_sdev->channel != sdev->channel || 769 tmp_sdev->id != sdev->id || 770 tmp_sdev->queue_depth == sdev->max_queue_depth) 771 continue; 772 773 scsi_change_queue_depth(tmp_sdev, tmp_sdev->queue_depth + 1); 774 sdev->last_queue_ramp_up = jiffies; 775 } 776 } 777 778 static void scsi_handle_queue_full(struct scsi_device *sdev) 779 { 780 const struct scsi_host_template *sht = sdev->host->hostt; 781 struct scsi_device *tmp_sdev; 782 783 if (!sht->track_queue_depth) 784 return; 785 786 shost_for_each_device(tmp_sdev, sdev->host) { 787 if (tmp_sdev->channel != sdev->channel || 788 tmp_sdev->id != sdev->id) 789 continue; 790 /* 791 * We do not know the number of commands that were at 792 * the device when we got the queue full so we start 793 * from the highest possible value and work our way down. 794 */ 795 scsi_track_queue_full(tmp_sdev, tmp_sdev->queue_depth - 1); 796 } 797 } 798 799 /** 800 * scsi_eh_completed_normally - Disposition a eh cmd on return from LLD. 801 * @scmd: SCSI cmd to examine. 802 * 803 * Notes: 804 * This is *only* called when we are examining the status of commands 805 * queued during error recovery. the main difference here is that we 806 * don't allow for the possibility of retries here, and we are a lot 807 * more restrictive about what we consider acceptable. 808 */ 809 static enum scsi_disposition scsi_eh_completed_normally(struct scsi_cmnd *scmd) 810 { 811 /* 812 * first check the host byte, to see if there is anything in there 813 * that would indicate what we need to do. 814 */ 815 if (host_byte(scmd->result) == DID_RESET) { 816 /* 817 * rats. we are already in the error handler, so we now 818 * get to try and figure out what to do next. if the sense 819 * is valid, we have a pretty good idea of what to do. 820 * if not, we mark it as FAILED. 821 */ 822 return scsi_check_sense(scmd); 823 } 824 if (host_byte(scmd->result) != DID_OK) 825 return FAILED; 826 827 /* 828 * now, check the status byte to see if this indicates 829 * anything special. 830 */ 831 switch (get_status_byte(scmd)) { 832 case SAM_STAT_GOOD: 833 scsi_handle_queue_ramp_up(scmd->device); 834 if (scmd->sense_buffer && SCSI_SENSE_VALID(scmd)) 835 /* 836 * If we have sense data, call scsi_check_sense() in 837 * order to set the correct SCSI ML byte (if any). 838 * No point in checking the return value, since the 839 * command has already completed successfully. 840 */ 841 scsi_check_sense(scmd); 842 fallthrough; 843 case SAM_STAT_COMMAND_TERMINATED: 844 return SUCCESS; 845 case SAM_STAT_CHECK_CONDITION: 846 return scsi_check_sense(scmd); 847 case SAM_STAT_CONDITION_MET: 848 case SAM_STAT_INTERMEDIATE: 849 case SAM_STAT_INTERMEDIATE_CONDITION_MET: 850 /* 851 * who knows? FIXME(eric) 852 */ 853 return SUCCESS; 854 case SAM_STAT_RESERVATION_CONFLICT: 855 if (scmd->cmnd[0] == TEST_UNIT_READY) 856 /* it is a success, we probed the device and 857 * found it */ 858 return SUCCESS; 859 /* otherwise, we failed to send the command */ 860 return FAILED; 861 case SAM_STAT_TASK_SET_FULL: 862 scsi_handle_queue_full(scmd->device); 863 fallthrough; 864 case SAM_STAT_BUSY: 865 return NEEDS_RETRY; 866 default: 867 return FAILED; 868 } 869 return FAILED; 870 } 871 872 /** 873 * scsi_eh_done - Completion function for error handling. 874 * @scmd: Cmd that is done. 875 */ 876 void scsi_eh_done(struct scsi_cmnd *scmd) 877 { 878 struct completion *eh_action; 879 880 SCSI_LOG_ERROR_RECOVERY(3, scmd_printk(KERN_INFO, scmd, 881 "%s result: %x\n", __func__, scmd->result)); 882 883 eh_action = scmd->device->host->eh_action; 884 if (eh_action) 885 complete(eh_action); 886 } 887 888 /** 889 * scsi_try_host_reset - ask host adapter to reset itself 890 * @scmd: SCSI cmd to send host reset. 891 */ 892 static enum scsi_disposition scsi_try_host_reset(struct scsi_cmnd *scmd) 893 { 894 unsigned long flags; 895 enum scsi_disposition rtn; 896 struct Scsi_Host *host = scmd->device->host; 897 const struct scsi_host_template *hostt = host->hostt; 898 899 SCSI_LOG_ERROR_RECOVERY(3, 900 shost_printk(KERN_INFO, host, "Snd Host RST\n")); 901 902 if (!hostt->eh_host_reset_handler) 903 return FAILED; 904 905 rtn = hostt->eh_host_reset_handler(scmd); 906 907 if (rtn == SUCCESS) { 908 if (!hostt->skip_settle_delay) 909 ssleep(HOST_RESET_SETTLE_TIME); 910 spin_lock_irqsave(host->host_lock, flags); 911 scsi_report_bus_reset(host, scmd_channel(scmd)); 912 spin_unlock_irqrestore(host->host_lock, flags); 913 } 914 915 return rtn; 916 } 917 918 /** 919 * scsi_try_bus_reset - ask host to perform a bus reset 920 * @scmd: SCSI cmd to send bus reset. 921 */ 922 static enum scsi_disposition scsi_try_bus_reset(struct scsi_cmnd *scmd) 923 { 924 unsigned long flags; 925 enum scsi_disposition rtn; 926 struct Scsi_Host *host = scmd->device->host; 927 const struct scsi_host_template *hostt = host->hostt; 928 929 SCSI_LOG_ERROR_RECOVERY(3, scmd_printk(KERN_INFO, scmd, 930 "%s: Snd Bus RST\n", __func__)); 931 932 if (!hostt->eh_bus_reset_handler) 933 return FAILED; 934 935 rtn = hostt->eh_bus_reset_handler(scmd); 936 937 if (rtn == SUCCESS) { 938 if (!hostt->skip_settle_delay) 939 ssleep(BUS_RESET_SETTLE_TIME); 940 spin_lock_irqsave(host->host_lock, flags); 941 scsi_report_bus_reset(host, scmd_channel(scmd)); 942 spin_unlock_irqrestore(host->host_lock, flags); 943 } 944 945 return rtn; 946 } 947 948 static void __scsi_report_device_reset(struct scsi_device *sdev, void *data) 949 { 950 sdev->was_reset = 1; 951 sdev->expecting_cc_ua = 1; 952 } 953 954 /** 955 * scsi_try_target_reset - Ask host to perform a target reset 956 * @scmd: SCSI cmd used to send a target reset 957 * 958 * Notes: 959 * There is no timeout for this operation. if this operation is 960 * unreliable for a given host, then the host itself needs to put a 961 * timer on it, and set the host back to a consistent state prior to 962 * returning. 963 */ 964 static enum scsi_disposition scsi_try_target_reset(struct scsi_cmnd *scmd) 965 { 966 unsigned long flags; 967 enum scsi_disposition rtn; 968 struct Scsi_Host *host = scmd->device->host; 969 const struct scsi_host_template *hostt = host->hostt; 970 971 if (!hostt->eh_target_reset_handler) 972 return FAILED; 973 974 rtn = hostt->eh_target_reset_handler(scmd); 975 if (rtn == SUCCESS) { 976 spin_lock_irqsave(host->host_lock, flags); 977 __starget_for_each_device(scsi_target(scmd->device), NULL, 978 __scsi_report_device_reset); 979 spin_unlock_irqrestore(host->host_lock, flags); 980 } 981 982 return rtn; 983 } 984 985 /** 986 * scsi_try_bus_device_reset - Ask host to perform a BDR on a dev 987 * @scmd: SCSI cmd used to send BDR 988 * 989 * Notes: 990 * There is no timeout for this operation. if this operation is 991 * unreliable for a given host, then the host itself needs to put a 992 * timer on it, and set the host back to a consistent state prior to 993 * returning. 994 */ 995 static enum scsi_disposition scsi_try_bus_device_reset(struct scsi_cmnd *scmd) 996 { 997 enum scsi_disposition rtn; 998 const struct scsi_host_template *hostt = scmd->device->host->hostt; 999 1000 if (!hostt->eh_device_reset_handler) 1001 return FAILED; 1002 1003 rtn = hostt->eh_device_reset_handler(scmd); 1004 if (rtn == SUCCESS) 1005 __scsi_report_device_reset(scmd->device, NULL); 1006 return rtn; 1007 } 1008 1009 /** 1010 * scsi_try_to_abort_cmd - Ask host to abort a SCSI command 1011 * @hostt: SCSI driver host template 1012 * @scmd: SCSI cmd used to send a target reset 1013 * 1014 * Return value: 1015 * SUCCESS, FAILED, or FAST_IO_FAIL 1016 * 1017 * Notes: 1018 * SUCCESS does not necessarily indicate that the command 1019 * has been aborted; it only indicates that the LLDDs 1020 * has cleared all references to that command. 1021 * LLDDs should return FAILED only if an abort was required 1022 * but could not be executed. LLDDs should return FAST_IO_FAIL 1023 * if the device is temporarily unavailable (eg due to a 1024 * link down on FibreChannel) 1025 */ 1026 static enum scsi_disposition 1027 scsi_try_to_abort_cmd(const struct scsi_host_template *hostt, struct scsi_cmnd *scmd) 1028 { 1029 if (!hostt->eh_abort_handler) 1030 return FAILED; 1031 1032 return hostt->eh_abort_handler(scmd); 1033 } 1034 1035 static void scsi_abort_eh_cmnd(struct scsi_cmnd *scmd) 1036 { 1037 if (scsi_try_to_abort_cmd(scmd->device->host->hostt, scmd) != SUCCESS) 1038 if (scsi_try_bus_device_reset(scmd) != SUCCESS) 1039 if (scsi_try_target_reset(scmd) != SUCCESS) 1040 if (scsi_try_bus_reset(scmd) != SUCCESS) 1041 scsi_try_host_reset(scmd); 1042 } 1043 1044 /** 1045 * scsi_eh_prep_cmnd - Save a scsi command info as part of error recovery 1046 * @scmd: SCSI command structure to hijack 1047 * @ses: structure to save restore information 1048 * @cmnd: CDB to send. Can be NULL if no new cmnd is needed 1049 * @cmnd_size: size in bytes of @cmnd (must be <= MAX_COMMAND_SIZE) 1050 * @sense_bytes: size of sense data to copy. or 0 (if != 0 @cmnd is ignored) 1051 * 1052 * This function is used to save a scsi command information before re-execution 1053 * as part of the error recovery process. If @sense_bytes is 0 the command 1054 * sent must be one that does not transfer any data. If @sense_bytes != 0 1055 * @cmnd is ignored and this functions sets up a REQUEST_SENSE command 1056 * and cmnd buffers to read @sense_bytes into @scmd->sense_buffer. 1057 */ 1058 void scsi_eh_prep_cmnd(struct scsi_cmnd *scmd, struct scsi_eh_save *ses, 1059 unsigned char *cmnd, int cmnd_size, unsigned sense_bytes) 1060 { 1061 struct scsi_device *sdev = scmd->device; 1062 1063 /* 1064 * We need saved copies of a number of fields - this is because 1065 * error handling may need to overwrite these with different values 1066 * to run different commands, and once error handling is complete, 1067 * we will need to restore these values prior to running the actual 1068 * command. 1069 */ 1070 ses->cmd_len = scmd->cmd_len; 1071 ses->data_direction = scmd->sc_data_direction; 1072 ses->sdb = scmd->sdb; 1073 ses->result = scmd->result; 1074 ses->resid_len = scmd->resid_len; 1075 ses->underflow = scmd->underflow; 1076 ses->prot_op = scmd->prot_op; 1077 ses->eh_eflags = scmd->eh_eflags; 1078 1079 scmd->prot_op = SCSI_PROT_NORMAL; 1080 scmd->eh_eflags = 0; 1081 memcpy(ses->cmnd, scmd->cmnd, sizeof(ses->cmnd)); 1082 memset(scmd->cmnd, 0, sizeof(scmd->cmnd)); 1083 memset(&scmd->sdb, 0, sizeof(scmd->sdb)); 1084 scmd->result = 0; 1085 scmd->resid_len = 0; 1086 1087 if (sense_bytes) { 1088 scmd->sdb.length = min_t(unsigned, SCSI_SENSE_BUFFERSIZE, 1089 sense_bytes); 1090 sg_init_one(&ses->sense_sgl, scmd->sense_buffer, 1091 scmd->sdb.length); 1092 scmd->sdb.table.sgl = &ses->sense_sgl; 1093 scmd->sc_data_direction = DMA_FROM_DEVICE; 1094 scmd->sdb.table.nents = scmd->sdb.table.orig_nents = 1; 1095 scmd->cmnd[0] = REQUEST_SENSE; 1096 scmd->cmnd[4] = scmd->sdb.length; 1097 scmd->cmd_len = COMMAND_SIZE(scmd->cmnd[0]); 1098 } else { 1099 scmd->sc_data_direction = DMA_NONE; 1100 if (cmnd) { 1101 BUG_ON(cmnd_size > sizeof(scmd->cmnd)); 1102 memcpy(scmd->cmnd, cmnd, cmnd_size); 1103 scmd->cmd_len = COMMAND_SIZE(scmd->cmnd[0]); 1104 } 1105 } 1106 1107 scmd->underflow = 0; 1108 1109 if (sdev->scsi_level <= SCSI_2 && sdev->scsi_level != SCSI_UNKNOWN) 1110 scmd->cmnd[1] = (scmd->cmnd[1] & 0x1f) | 1111 (sdev->lun << 5 & 0xe0); 1112 1113 /* 1114 * Zero the sense buffer. The scsi spec mandates that any 1115 * untransferred sense data should be interpreted as being zero. 1116 */ 1117 memset(scmd->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE); 1118 } 1119 EXPORT_SYMBOL(scsi_eh_prep_cmnd); 1120 1121 /** 1122 * scsi_eh_restore_cmnd - Restore a scsi command info as part of error recovery 1123 * @scmd: SCSI command structure to restore 1124 * @ses: saved information from a coresponding call to scsi_eh_prep_cmnd 1125 * 1126 * Undo any damage done by above scsi_eh_prep_cmnd(). 1127 */ 1128 void scsi_eh_restore_cmnd(struct scsi_cmnd* scmd, struct scsi_eh_save *ses) 1129 { 1130 /* 1131 * Restore original data 1132 */ 1133 scmd->cmd_len = ses->cmd_len; 1134 memcpy(scmd->cmnd, ses->cmnd, sizeof(ses->cmnd)); 1135 scmd->sc_data_direction = ses->data_direction; 1136 scmd->sdb = ses->sdb; 1137 scmd->result = ses->result; 1138 scmd->resid_len = ses->resid_len; 1139 scmd->underflow = ses->underflow; 1140 scmd->prot_op = ses->prot_op; 1141 scmd->eh_eflags = ses->eh_eflags; 1142 } 1143 EXPORT_SYMBOL(scsi_eh_restore_cmnd); 1144 1145 /** 1146 * scsi_send_eh_cmnd - submit a scsi command as part of error recovery 1147 * @scmd: SCSI command structure to hijack 1148 * @cmnd: CDB to send 1149 * @cmnd_size: size in bytes of @cmnd 1150 * @timeout: timeout for this request 1151 * @sense_bytes: size of sense data to copy or 0 1152 * 1153 * This function is used to send a scsi command down to a target device 1154 * as part of the error recovery process. See also scsi_eh_prep_cmnd() above. 1155 * 1156 * Return value: 1157 * SUCCESS or FAILED or NEEDS_RETRY 1158 */ 1159 static enum scsi_disposition scsi_send_eh_cmnd(struct scsi_cmnd *scmd, 1160 unsigned char *cmnd, int cmnd_size, int timeout, unsigned sense_bytes) 1161 { 1162 struct scsi_device *sdev = scmd->device; 1163 struct Scsi_Host *shost = sdev->host; 1164 DECLARE_COMPLETION_ONSTACK(done); 1165 unsigned long timeleft = timeout, delay; 1166 struct scsi_eh_save ses; 1167 const unsigned long stall_for = msecs_to_jiffies(100); 1168 int rtn; 1169 1170 retry: 1171 scsi_eh_prep_cmnd(scmd, &ses, cmnd, cmnd_size, sense_bytes); 1172 shost->eh_action = &done; 1173 1174 scsi_log_send(scmd); 1175 scmd->submitter = SUBMITTED_BY_SCSI_ERROR_HANDLER; 1176 scmd->flags |= SCMD_LAST; 1177 1178 /* 1179 * Lock sdev->state_mutex to avoid that scsi_device_quiesce() can 1180 * change the SCSI device state after we have examined it and before 1181 * .queuecommand() is called. 1182 */ 1183 mutex_lock(&sdev->state_mutex); 1184 while (sdev->sdev_state == SDEV_BLOCK && timeleft > 0) { 1185 mutex_unlock(&sdev->state_mutex); 1186 SCSI_LOG_ERROR_RECOVERY(5, sdev_printk(KERN_DEBUG, sdev, 1187 "%s: state %d <> %d\n", __func__, sdev->sdev_state, 1188 SDEV_BLOCK)); 1189 delay = min(timeleft, stall_for); 1190 timeleft -= delay; 1191 msleep(jiffies_to_msecs(delay)); 1192 mutex_lock(&sdev->state_mutex); 1193 } 1194 if (sdev->sdev_state != SDEV_BLOCK) 1195 rtn = shost->hostt->queuecommand(shost, scmd); 1196 else 1197 rtn = FAILED; 1198 mutex_unlock(&sdev->state_mutex); 1199 1200 if (rtn) { 1201 if (timeleft > stall_for) { 1202 scsi_eh_restore_cmnd(scmd, &ses); 1203 1204 timeleft -= stall_for; 1205 msleep(jiffies_to_msecs(stall_for)); 1206 goto retry; 1207 } 1208 /* signal not to enter either branch of the if () below */ 1209 timeleft = 0; 1210 rtn = FAILED; 1211 } else { 1212 timeleft = wait_for_completion_timeout(&done, timeout); 1213 rtn = SUCCESS; 1214 } 1215 1216 shost->eh_action = NULL; 1217 1218 scsi_log_completion(scmd, rtn); 1219 1220 SCSI_LOG_ERROR_RECOVERY(3, scmd_printk(KERN_INFO, scmd, 1221 "%s timeleft: %ld\n", 1222 __func__, timeleft)); 1223 1224 /* 1225 * If there is time left scsi_eh_done got called, and we will examine 1226 * the actual status codes to see whether the command actually did 1227 * complete normally, else if we have a zero return and no time left, 1228 * the command must still be pending, so abort it and return FAILED. 1229 * If we never actually managed to issue the command, because 1230 * ->queuecommand() kept returning non zero, use the rtn = FAILED 1231 * value above (so don't execute either branch of the if) 1232 */ 1233 if (timeleft) { 1234 rtn = scsi_eh_completed_normally(scmd); 1235 SCSI_LOG_ERROR_RECOVERY(3, scmd_printk(KERN_INFO, scmd, 1236 "%s: scsi_eh_completed_normally %x\n", __func__, rtn)); 1237 1238 switch (rtn) { 1239 case SUCCESS: 1240 case NEEDS_RETRY: 1241 case FAILED: 1242 break; 1243 case ADD_TO_MLQUEUE: 1244 rtn = NEEDS_RETRY; 1245 break; 1246 default: 1247 rtn = FAILED; 1248 break; 1249 } 1250 } else if (rtn != FAILED) { 1251 scsi_abort_eh_cmnd(scmd); 1252 rtn = FAILED; 1253 } 1254 1255 scsi_eh_restore_cmnd(scmd, &ses); 1256 1257 return rtn; 1258 } 1259 1260 /** 1261 * scsi_request_sense - Request sense data from a particular target. 1262 * @scmd: SCSI cmd for request sense. 1263 * 1264 * Notes: 1265 * Some hosts automatically obtain this information, others require 1266 * that we obtain it on our own. This function will *not* return until 1267 * the command either times out, or it completes. 1268 */ 1269 static enum scsi_disposition scsi_request_sense(struct scsi_cmnd *scmd) 1270 { 1271 return scsi_send_eh_cmnd(scmd, NULL, 0, scmd->device->eh_timeout, ~0); 1272 } 1273 1274 static enum scsi_disposition 1275 scsi_eh_action(struct scsi_cmnd *scmd, enum scsi_disposition rtn) 1276 { 1277 if (!blk_rq_is_passthrough(scsi_cmd_to_rq(scmd))) { 1278 struct scsi_driver *sdrv = scsi_cmd_to_driver(scmd); 1279 if (sdrv->eh_action) 1280 rtn = sdrv->eh_action(scmd, rtn); 1281 } 1282 return rtn; 1283 } 1284 1285 /** 1286 * scsi_eh_finish_cmd - Handle a cmd that eh is finished with. 1287 * @scmd: Original SCSI cmd that eh has finished. 1288 * @done_q: Queue for processed commands. 1289 * 1290 * Notes: 1291 * We don't want to use the normal command completion while we are are 1292 * still handling errors - it may cause other commands to be queued, 1293 * and that would disturb what we are doing. Thus we really want to 1294 * keep a list of pending commands for final completion, and once we 1295 * are ready to leave error handling we handle completion for real. 1296 */ 1297 void scsi_eh_finish_cmd(struct scsi_cmnd *scmd, struct list_head *done_q) 1298 { 1299 list_move_tail(&scmd->eh_entry, done_q); 1300 } 1301 EXPORT_SYMBOL(scsi_eh_finish_cmd); 1302 1303 /** 1304 * scsi_eh_get_sense - Get device sense data. 1305 * @work_q: Queue of commands to process. 1306 * @done_q: Queue of processed commands. 1307 * 1308 * Description: 1309 * See if we need to request sense information. if so, then get it 1310 * now, so we have a better idea of what to do. 1311 * 1312 * Notes: 1313 * This has the unfortunate side effect that if a shost adapter does 1314 * not automatically request sense information, we end up shutting 1315 * it down before we request it. 1316 * 1317 * All drivers should request sense information internally these days, 1318 * so for now all I have to say is tough noogies if you end up in here. 1319 * 1320 * XXX: Long term this code should go away, but that needs an audit of 1321 * all LLDDs first. 1322 */ 1323 int scsi_eh_get_sense(struct list_head *work_q, 1324 struct list_head *done_q) 1325 { 1326 struct scsi_cmnd *scmd, *next; 1327 struct Scsi_Host *shost; 1328 enum scsi_disposition rtn; 1329 1330 /* 1331 * If SCSI_EH_ABORT_SCHEDULED has been set, it is timeout IO, 1332 * should not get sense. 1333 */ 1334 list_for_each_entry_safe(scmd, next, work_q, eh_entry) { 1335 if ((scmd->eh_eflags & SCSI_EH_ABORT_SCHEDULED) || 1336 SCSI_SENSE_VALID(scmd)) 1337 continue; 1338 1339 shost = scmd->device->host; 1340 if (scsi_host_eh_past_deadline(shost)) { 1341 SCSI_LOG_ERROR_RECOVERY(3, 1342 scmd_printk(KERN_INFO, scmd, 1343 "%s: skip request sense, past eh deadline\n", 1344 current->comm)); 1345 break; 1346 } 1347 if (!scsi_status_is_check_condition(scmd->result)) 1348 /* 1349 * don't request sense if there's no check condition 1350 * status because the error we're processing isn't one 1351 * that has a sense code (and some devices get 1352 * confused by sense requests out of the blue) 1353 */ 1354 continue; 1355 1356 SCSI_LOG_ERROR_RECOVERY(2, scmd_printk(KERN_INFO, scmd, 1357 "%s: requesting sense\n", 1358 current->comm)); 1359 rtn = scsi_request_sense(scmd); 1360 if (rtn != SUCCESS) 1361 continue; 1362 1363 SCSI_LOG_ERROR_RECOVERY(3, scmd_printk(KERN_INFO, scmd, 1364 "sense requested, result %x\n", scmd->result)); 1365 SCSI_LOG_ERROR_RECOVERY(3, scsi_print_sense(scmd)); 1366 1367 rtn = scsi_decide_disposition(scmd); 1368 1369 /* 1370 * if the result was normal, then just pass it along to the 1371 * upper level. 1372 */ 1373 if (rtn == SUCCESS) 1374 /* 1375 * We don't want this command reissued, just finished 1376 * with the sense data, so set retries to the max 1377 * allowed to ensure it won't get reissued. If the user 1378 * has requested infinite retries, we also want to 1379 * finish this command, so force completion by setting 1380 * retries and allowed to the same value. 1381 */ 1382 if (scmd->allowed == SCSI_CMD_RETRIES_NO_LIMIT) 1383 scmd->retries = scmd->allowed = 1; 1384 else 1385 scmd->retries = scmd->allowed; 1386 else if (rtn != NEEDS_RETRY) 1387 continue; 1388 1389 scsi_eh_finish_cmd(scmd, done_q); 1390 } 1391 1392 return list_empty(work_q); 1393 } 1394 EXPORT_SYMBOL_GPL(scsi_eh_get_sense); 1395 1396 /** 1397 * scsi_eh_tur - Send TUR to device. 1398 * @scmd: &scsi_cmnd to send TUR 1399 * 1400 * Return value: 1401 * 0 - Device is ready. 1 - Device NOT ready. 1402 */ 1403 static int scsi_eh_tur(struct scsi_cmnd *scmd) 1404 { 1405 static unsigned char tur_command[6] = {TEST_UNIT_READY, 0, 0, 0, 0, 0}; 1406 int retry_cnt = 1; 1407 enum scsi_disposition rtn; 1408 1409 retry_tur: 1410 rtn = scsi_send_eh_cmnd(scmd, tur_command, 6, 1411 scmd->device->eh_timeout, 0); 1412 1413 SCSI_LOG_ERROR_RECOVERY(3, scmd_printk(KERN_INFO, scmd, 1414 "%s return: %x\n", __func__, rtn)); 1415 1416 switch (rtn) { 1417 case NEEDS_RETRY: 1418 if (retry_cnt--) 1419 goto retry_tur; 1420 fallthrough; 1421 case SUCCESS: 1422 return 0; 1423 default: 1424 return 1; 1425 } 1426 } 1427 1428 /** 1429 * scsi_eh_test_devices - check if devices are responding from error recovery. 1430 * @cmd_list: scsi commands in error recovery. 1431 * @work_q: queue for commands which still need more error recovery 1432 * @done_q: queue for commands which are finished 1433 * @try_stu: boolean on if a STU command should be tried in addition to TUR. 1434 * 1435 * Decription: 1436 * Tests if devices are in a working state. Commands to devices now in 1437 * a working state are sent to the done_q while commands to devices which 1438 * are still failing to respond are returned to the work_q for more 1439 * processing. 1440 **/ 1441 static int scsi_eh_test_devices(struct list_head *cmd_list, 1442 struct list_head *work_q, 1443 struct list_head *done_q, int try_stu) 1444 { 1445 struct scsi_cmnd *scmd, *next; 1446 struct scsi_device *sdev; 1447 int finish_cmds; 1448 1449 while (!list_empty(cmd_list)) { 1450 scmd = list_entry(cmd_list->next, struct scsi_cmnd, eh_entry); 1451 sdev = scmd->device; 1452 1453 if (!try_stu) { 1454 if (scsi_host_eh_past_deadline(sdev->host)) { 1455 /* Push items back onto work_q */ 1456 list_splice_init(cmd_list, work_q); 1457 SCSI_LOG_ERROR_RECOVERY(3, 1458 sdev_printk(KERN_INFO, sdev, 1459 "%s: skip test device, past eh deadline", 1460 current->comm)); 1461 break; 1462 } 1463 } 1464 1465 finish_cmds = !scsi_device_online(scmd->device) || 1466 (try_stu && !scsi_eh_try_stu(scmd) && 1467 !scsi_eh_tur(scmd)) || 1468 !scsi_eh_tur(scmd); 1469 1470 list_for_each_entry_safe(scmd, next, cmd_list, eh_entry) 1471 if (scmd->device == sdev) { 1472 if (finish_cmds && 1473 (try_stu || 1474 scsi_eh_action(scmd, SUCCESS) == SUCCESS)) 1475 scsi_eh_finish_cmd(scmd, done_q); 1476 else 1477 list_move_tail(&scmd->eh_entry, work_q); 1478 } 1479 } 1480 return list_empty(work_q); 1481 } 1482 1483 /** 1484 * scsi_eh_try_stu - Send START_UNIT to device. 1485 * @scmd: &scsi_cmnd to send START_UNIT 1486 * 1487 * Return value: 1488 * 0 - Device is ready. 1 - Device NOT ready. 1489 */ 1490 static int scsi_eh_try_stu(struct scsi_cmnd *scmd) 1491 { 1492 static unsigned char stu_command[6] = {START_STOP, 0, 0, 0, 1, 0}; 1493 1494 if (scmd->device->allow_restart) { 1495 int i; 1496 enum scsi_disposition rtn = NEEDS_RETRY; 1497 1498 for (i = 0; rtn == NEEDS_RETRY && i < 2; i++) 1499 rtn = scsi_send_eh_cmnd(scmd, stu_command, 6, 1500 scmd->device->eh_timeout, 0); 1501 1502 if (rtn == SUCCESS) 1503 return 0; 1504 } 1505 1506 return 1; 1507 } 1508 1509 /** 1510 * scsi_eh_stu - send START_UNIT if needed 1511 * @shost: &scsi host being recovered. 1512 * @work_q: &list_head for pending commands. 1513 * @done_q: &list_head for processed commands. 1514 * 1515 * Notes: 1516 * If commands are failing due to not ready, initializing command required, 1517 * try revalidating the device, which will end up sending a start unit. 1518 */ 1519 static int scsi_eh_stu(struct Scsi_Host *shost, 1520 struct list_head *work_q, 1521 struct list_head *done_q) 1522 { 1523 struct scsi_cmnd *scmd, *stu_scmd, *next; 1524 struct scsi_device *sdev; 1525 1526 shost_for_each_device(sdev, shost) { 1527 if (scsi_host_eh_past_deadline(shost)) { 1528 SCSI_LOG_ERROR_RECOVERY(3, 1529 sdev_printk(KERN_INFO, sdev, 1530 "%s: skip START_UNIT, past eh deadline\n", 1531 current->comm)); 1532 scsi_device_put(sdev); 1533 break; 1534 } 1535 stu_scmd = NULL; 1536 list_for_each_entry(scmd, work_q, eh_entry) 1537 if (scmd->device == sdev && SCSI_SENSE_VALID(scmd) && 1538 scsi_check_sense(scmd) == FAILED ) { 1539 stu_scmd = scmd; 1540 break; 1541 } 1542 1543 if (!stu_scmd) 1544 continue; 1545 1546 SCSI_LOG_ERROR_RECOVERY(3, 1547 sdev_printk(KERN_INFO, sdev, 1548 "%s: Sending START_UNIT\n", 1549 current->comm)); 1550 1551 if (!scsi_eh_try_stu(stu_scmd)) { 1552 if (!scsi_device_online(sdev) || 1553 !scsi_eh_tur(stu_scmd)) { 1554 list_for_each_entry_safe(scmd, next, 1555 work_q, eh_entry) { 1556 if (scmd->device == sdev && 1557 scsi_eh_action(scmd, SUCCESS) == SUCCESS) 1558 scsi_eh_finish_cmd(scmd, done_q); 1559 } 1560 } 1561 } else { 1562 SCSI_LOG_ERROR_RECOVERY(3, 1563 sdev_printk(KERN_INFO, sdev, 1564 "%s: START_UNIT failed\n", 1565 current->comm)); 1566 } 1567 } 1568 1569 return list_empty(work_q); 1570 } 1571 1572 1573 /** 1574 * scsi_eh_bus_device_reset - send bdr if needed 1575 * @shost: scsi host being recovered. 1576 * @work_q: &list_head for pending commands. 1577 * @done_q: &list_head for processed commands. 1578 * 1579 * Notes: 1580 * Try a bus device reset. Still, look to see whether we have multiple 1581 * devices that are jammed or not - if we have multiple devices, it 1582 * makes no sense to try bus_device_reset - we really would need to try 1583 * a bus_reset instead. 1584 */ 1585 static int scsi_eh_bus_device_reset(struct Scsi_Host *shost, 1586 struct list_head *work_q, 1587 struct list_head *done_q) 1588 { 1589 struct scsi_cmnd *scmd, *bdr_scmd, *next; 1590 struct scsi_device *sdev; 1591 enum scsi_disposition rtn; 1592 1593 shost_for_each_device(sdev, shost) { 1594 if (scsi_host_eh_past_deadline(shost)) { 1595 SCSI_LOG_ERROR_RECOVERY(3, 1596 sdev_printk(KERN_INFO, sdev, 1597 "%s: skip BDR, past eh deadline\n", 1598 current->comm)); 1599 scsi_device_put(sdev); 1600 break; 1601 } 1602 bdr_scmd = NULL; 1603 list_for_each_entry(scmd, work_q, eh_entry) 1604 if (scmd->device == sdev) { 1605 bdr_scmd = scmd; 1606 break; 1607 } 1608 1609 if (!bdr_scmd) 1610 continue; 1611 1612 SCSI_LOG_ERROR_RECOVERY(3, 1613 sdev_printk(KERN_INFO, sdev, 1614 "%s: Sending BDR\n", current->comm)); 1615 rtn = scsi_try_bus_device_reset(bdr_scmd); 1616 if (rtn == SUCCESS || rtn == FAST_IO_FAIL) { 1617 if (!scsi_device_online(sdev) || 1618 rtn == FAST_IO_FAIL || 1619 !scsi_eh_tur(bdr_scmd)) { 1620 list_for_each_entry_safe(scmd, next, 1621 work_q, eh_entry) { 1622 if (scmd->device == sdev && 1623 scsi_eh_action(scmd, rtn) != FAILED) 1624 scsi_eh_finish_cmd(scmd, 1625 done_q); 1626 } 1627 } 1628 } else { 1629 SCSI_LOG_ERROR_RECOVERY(3, 1630 sdev_printk(KERN_INFO, sdev, 1631 "%s: BDR failed\n", current->comm)); 1632 } 1633 } 1634 1635 return list_empty(work_q); 1636 } 1637 1638 /** 1639 * scsi_eh_target_reset - send target reset if needed 1640 * @shost: scsi host being recovered. 1641 * @work_q: &list_head for pending commands. 1642 * @done_q: &list_head for processed commands. 1643 * 1644 * Notes: 1645 * Try a target reset. 1646 */ 1647 static int scsi_eh_target_reset(struct Scsi_Host *shost, 1648 struct list_head *work_q, 1649 struct list_head *done_q) 1650 { 1651 LIST_HEAD(tmp_list); 1652 LIST_HEAD(check_list); 1653 1654 list_splice_init(work_q, &tmp_list); 1655 1656 while (!list_empty(&tmp_list)) { 1657 struct scsi_cmnd *next, *scmd; 1658 enum scsi_disposition rtn; 1659 unsigned int id; 1660 1661 if (scsi_host_eh_past_deadline(shost)) { 1662 /* push back on work queue for further processing */ 1663 list_splice_init(&check_list, work_q); 1664 list_splice_init(&tmp_list, work_q); 1665 SCSI_LOG_ERROR_RECOVERY(3, 1666 shost_printk(KERN_INFO, shost, 1667 "%s: Skip target reset, past eh deadline\n", 1668 current->comm)); 1669 return list_empty(work_q); 1670 } 1671 1672 scmd = list_entry(tmp_list.next, struct scsi_cmnd, eh_entry); 1673 id = scmd_id(scmd); 1674 1675 SCSI_LOG_ERROR_RECOVERY(3, 1676 shost_printk(KERN_INFO, shost, 1677 "%s: Sending target reset to target %d\n", 1678 current->comm, id)); 1679 rtn = scsi_try_target_reset(scmd); 1680 if (rtn != SUCCESS && rtn != FAST_IO_FAIL) 1681 SCSI_LOG_ERROR_RECOVERY(3, 1682 shost_printk(KERN_INFO, shost, 1683 "%s: Target reset failed" 1684 " target: %d\n", 1685 current->comm, id)); 1686 list_for_each_entry_safe(scmd, next, &tmp_list, eh_entry) { 1687 if (scmd_id(scmd) != id) 1688 continue; 1689 1690 if (rtn == SUCCESS) 1691 list_move_tail(&scmd->eh_entry, &check_list); 1692 else if (rtn == FAST_IO_FAIL) 1693 scsi_eh_finish_cmd(scmd, done_q); 1694 else 1695 /* push back on work queue for further processing */ 1696 list_move(&scmd->eh_entry, work_q); 1697 } 1698 } 1699 1700 return scsi_eh_test_devices(&check_list, work_q, done_q, 0); 1701 } 1702 1703 /** 1704 * scsi_eh_bus_reset - send a bus reset 1705 * @shost: &scsi host being recovered. 1706 * @work_q: &list_head for pending commands. 1707 * @done_q: &list_head for processed commands. 1708 */ 1709 static int scsi_eh_bus_reset(struct Scsi_Host *shost, 1710 struct list_head *work_q, 1711 struct list_head *done_q) 1712 { 1713 struct scsi_cmnd *scmd, *chan_scmd, *next; 1714 LIST_HEAD(check_list); 1715 unsigned int channel; 1716 enum scsi_disposition rtn; 1717 1718 /* 1719 * we really want to loop over the various channels, and do this on 1720 * a channel by channel basis. we should also check to see if any 1721 * of the failed commands are on soft_reset devices, and if so, skip 1722 * the reset. 1723 */ 1724 1725 for (channel = 0; channel <= shost->max_channel; channel++) { 1726 if (scsi_host_eh_past_deadline(shost)) { 1727 list_splice_init(&check_list, work_q); 1728 SCSI_LOG_ERROR_RECOVERY(3, 1729 shost_printk(KERN_INFO, shost, 1730 "%s: skip BRST, past eh deadline\n", 1731 current->comm)); 1732 return list_empty(work_q); 1733 } 1734 1735 chan_scmd = NULL; 1736 list_for_each_entry(scmd, work_q, eh_entry) { 1737 if (channel == scmd_channel(scmd)) { 1738 chan_scmd = scmd; 1739 break; 1740 /* 1741 * FIXME add back in some support for 1742 * soft_reset devices. 1743 */ 1744 } 1745 } 1746 1747 if (!chan_scmd) 1748 continue; 1749 SCSI_LOG_ERROR_RECOVERY(3, 1750 shost_printk(KERN_INFO, shost, 1751 "%s: Sending BRST chan: %d\n", 1752 current->comm, channel)); 1753 rtn = scsi_try_bus_reset(chan_scmd); 1754 if (rtn == SUCCESS || rtn == FAST_IO_FAIL) { 1755 list_for_each_entry_safe(scmd, next, work_q, eh_entry) { 1756 if (channel == scmd_channel(scmd)) { 1757 if (rtn == FAST_IO_FAIL) 1758 scsi_eh_finish_cmd(scmd, 1759 done_q); 1760 else 1761 list_move_tail(&scmd->eh_entry, 1762 &check_list); 1763 } 1764 } 1765 } else { 1766 SCSI_LOG_ERROR_RECOVERY(3, 1767 shost_printk(KERN_INFO, shost, 1768 "%s: BRST failed chan: %d\n", 1769 current->comm, channel)); 1770 } 1771 } 1772 return scsi_eh_test_devices(&check_list, work_q, done_q, 0); 1773 } 1774 1775 /** 1776 * scsi_eh_host_reset - send a host reset 1777 * @shost: host to be reset. 1778 * @work_q: &list_head for pending commands. 1779 * @done_q: &list_head for processed commands. 1780 */ 1781 static int scsi_eh_host_reset(struct Scsi_Host *shost, 1782 struct list_head *work_q, 1783 struct list_head *done_q) 1784 { 1785 struct scsi_cmnd *scmd, *next; 1786 LIST_HEAD(check_list); 1787 enum scsi_disposition rtn; 1788 1789 if (!list_empty(work_q)) { 1790 scmd = list_entry(work_q->next, 1791 struct scsi_cmnd, eh_entry); 1792 1793 SCSI_LOG_ERROR_RECOVERY(3, 1794 shost_printk(KERN_INFO, shost, 1795 "%s: Sending HRST\n", 1796 current->comm)); 1797 1798 rtn = scsi_try_host_reset(scmd); 1799 if (rtn == SUCCESS) { 1800 list_splice_init(work_q, &check_list); 1801 } else if (rtn == FAST_IO_FAIL) { 1802 list_for_each_entry_safe(scmd, next, work_q, eh_entry) { 1803 scsi_eh_finish_cmd(scmd, done_q); 1804 } 1805 } else { 1806 SCSI_LOG_ERROR_RECOVERY(3, 1807 shost_printk(KERN_INFO, shost, 1808 "%s: HRST failed\n", 1809 current->comm)); 1810 } 1811 } 1812 return scsi_eh_test_devices(&check_list, work_q, done_q, 1); 1813 } 1814 1815 /** 1816 * scsi_eh_offline_sdevs - offline scsi devices that fail to recover 1817 * @work_q: &list_head for pending commands. 1818 * @done_q: &list_head for processed commands. 1819 */ 1820 static void scsi_eh_offline_sdevs(struct list_head *work_q, 1821 struct list_head *done_q) 1822 { 1823 struct scsi_cmnd *scmd, *next; 1824 struct scsi_device *sdev; 1825 1826 list_for_each_entry_safe(scmd, next, work_q, eh_entry) { 1827 sdev_printk(KERN_INFO, scmd->device, "Device offlined - " 1828 "not ready after error recovery\n"); 1829 sdev = scmd->device; 1830 1831 mutex_lock(&sdev->state_mutex); 1832 scsi_device_set_state(sdev, SDEV_OFFLINE); 1833 mutex_unlock(&sdev->state_mutex); 1834 1835 scsi_eh_finish_cmd(scmd, done_q); 1836 } 1837 return; 1838 } 1839 1840 /** 1841 * scsi_noretry_cmd - determine if command should be failed fast 1842 * @scmd: SCSI cmd to examine. 1843 */ 1844 bool scsi_noretry_cmd(struct scsi_cmnd *scmd) 1845 { 1846 struct request *req = scsi_cmd_to_rq(scmd); 1847 1848 switch (host_byte(scmd->result)) { 1849 case DID_OK: 1850 break; 1851 case DID_TIME_OUT: 1852 goto check_type; 1853 case DID_BUS_BUSY: 1854 return !!(req->cmd_flags & REQ_FAILFAST_TRANSPORT); 1855 case DID_PARITY: 1856 return !!(req->cmd_flags & REQ_FAILFAST_DEV); 1857 case DID_ERROR: 1858 if (get_status_byte(scmd) == SAM_STAT_RESERVATION_CONFLICT) 1859 return false; 1860 fallthrough; 1861 case DID_SOFT_ERROR: 1862 return !!(req->cmd_flags & REQ_FAILFAST_DRIVER); 1863 } 1864 1865 /* Never retry commands aborted due to a duration limit timeout */ 1866 if (scsi_ml_byte(scmd->result) == SCSIML_STAT_DL_TIMEOUT) 1867 return true; 1868 1869 if (!scsi_status_is_check_condition(scmd->result)) 1870 return false; 1871 1872 check_type: 1873 /* 1874 * assume caller has checked sense and determined 1875 * the check condition was retryable. 1876 */ 1877 if (req->cmd_flags & REQ_FAILFAST_DEV || blk_rq_is_passthrough(req)) 1878 return true; 1879 1880 return false; 1881 } 1882 1883 /** 1884 * scsi_decide_disposition - Disposition a cmd on return from LLD. 1885 * @scmd: SCSI cmd to examine. 1886 * 1887 * Notes: 1888 * This is *only* called when we are examining the status after sending 1889 * out the actual data command. any commands that are queued for error 1890 * recovery (e.g. test_unit_ready) do *not* come through here. 1891 * 1892 * When this routine returns failed, it means the error handler thread 1893 * is woken. In cases where the error code indicates an error that 1894 * doesn't require the error handler read (i.e. we don't need to 1895 * abort/reset), this function should return SUCCESS. 1896 */ 1897 enum scsi_disposition scsi_decide_disposition(struct scsi_cmnd *scmd) 1898 { 1899 enum scsi_disposition rtn; 1900 1901 /* 1902 * if the device is offline, then we clearly just pass the result back 1903 * up to the top level. 1904 */ 1905 if (!scsi_device_online(scmd->device)) { 1906 SCSI_LOG_ERROR_RECOVERY(5, scmd_printk(KERN_INFO, scmd, 1907 "%s: device offline - report as SUCCESS\n", __func__)); 1908 return SUCCESS; 1909 } 1910 1911 /* 1912 * first check the host byte, to see if there is anything in there 1913 * that would indicate what we need to do. 1914 */ 1915 switch (host_byte(scmd->result)) { 1916 case DID_PASSTHROUGH: 1917 /* 1918 * no matter what, pass this through to the upper layer. 1919 * nuke this special code so that it looks like we are saying 1920 * did_ok. 1921 */ 1922 scmd->result &= 0xff00ffff; 1923 return SUCCESS; 1924 case DID_OK: 1925 /* 1926 * looks good. drop through, and check the next byte. 1927 */ 1928 break; 1929 case DID_ABORT: 1930 if (scmd->eh_eflags & SCSI_EH_ABORT_SCHEDULED) { 1931 set_host_byte(scmd, DID_TIME_OUT); 1932 return SUCCESS; 1933 } 1934 fallthrough; 1935 case DID_NO_CONNECT: 1936 case DID_BAD_TARGET: 1937 /* 1938 * note - this means that we just report the status back 1939 * to the top level driver, not that we actually think 1940 * that it indicates SUCCESS. 1941 */ 1942 return SUCCESS; 1943 case DID_SOFT_ERROR: 1944 /* 1945 * when the low level driver returns did_soft_error, 1946 * it is responsible for keeping an internal retry counter 1947 * in order to avoid endless loops (db) 1948 */ 1949 goto maybe_retry; 1950 case DID_IMM_RETRY: 1951 return NEEDS_RETRY; 1952 1953 case DID_REQUEUE: 1954 return ADD_TO_MLQUEUE; 1955 case DID_TRANSPORT_DISRUPTED: 1956 /* 1957 * LLD/transport was disrupted during processing of the IO. 1958 * The transport class is now blocked/blocking, 1959 * and the transport will decide what to do with the IO 1960 * based on its timers and recovery capablilities if 1961 * there are enough retries. 1962 */ 1963 goto maybe_retry; 1964 case DID_TRANSPORT_FAILFAST: 1965 /* 1966 * The transport decided to failfast the IO (most likely 1967 * the fast io fail tmo fired), so send IO directly upwards. 1968 */ 1969 return SUCCESS; 1970 case DID_TRANSPORT_MARGINAL: 1971 /* 1972 * caller has decided not to do retries on 1973 * abort success, so send IO directly upwards 1974 */ 1975 return SUCCESS; 1976 case DID_ERROR: 1977 if (get_status_byte(scmd) == SAM_STAT_RESERVATION_CONFLICT) 1978 /* 1979 * execute reservation conflict processing code 1980 * lower down 1981 */ 1982 break; 1983 fallthrough; 1984 case DID_BUS_BUSY: 1985 case DID_PARITY: 1986 goto maybe_retry; 1987 case DID_TIME_OUT: 1988 /* 1989 * when we scan the bus, we get timeout messages for 1990 * these commands if there is no device available. 1991 * other hosts report did_no_connect for the same thing. 1992 */ 1993 if ((scmd->cmnd[0] == TEST_UNIT_READY || 1994 scmd->cmnd[0] == INQUIRY)) { 1995 return SUCCESS; 1996 } else { 1997 return FAILED; 1998 } 1999 case DID_RESET: 2000 return SUCCESS; 2001 default: 2002 return FAILED; 2003 } 2004 2005 /* 2006 * check the status byte to see if this indicates anything special. 2007 */ 2008 switch (get_status_byte(scmd)) { 2009 case SAM_STAT_TASK_SET_FULL: 2010 scsi_handle_queue_full(scmd->device); 2011 /* 2012 * the case of trying to send too many commands to a 2013 * tagged queueing device. 2014 */ 2015 fallthrough; 2016 case SAM_STAT_BUSY: 2017 /* 2018 * device can't talk to us at the moment. Should only 2019 * occur (SAM-3) when the task queue is empty, so will cause 2020 * the empty queue handling to trigger a stall in the 2021 * device. 2022 */ 2023 return ADD_TO_MLQUEUE; 2024 case SAM_STAT_GOOD: 2025 if (scmd->cmnd[0] == REPORT_LUNS) 2026 scmd->device->sdev_target->expecting_lun_change = 0; 2027 scsi_handle_queue_ramp_up(scmd->device); 2028 if (scmd->sense_buffer && SCSI_SENSE_VALID(scmd)) 2029 /* 2030 * If we have sense data, call scsi_check_sense() in 2031 * order to set the correct SCSI ML byte (if any). 2032 * No point in checking the return value, since the 2033 * command has already completed successfully. 2034 */ 2035 scsi_check_sense(scmd); 2036 fallthrough; 2037 case SAM_STAT_COMMAND_TERMINATED: 2038 return SUCCESS; 2039 case SAM_STAT_TASK_ABORTED: 2040 goto maybe_retry; 2041 case SAM_STAT_CHECK_CONDITION: 2042 rtn = scsi_check_sense(scmd); 2043 if (rtn == NEEDS_RETRY) 2044 goto maybe_retry; 2045 /* if rtn == FAILED, we have no sense information; 2046 * returning FAILED will wake the error handler thread 2047 * to collect the sense and redo the decide 2048 * disposition */ 2049 return rtn; 2050 case SAM_STAT_CONDITION_MET: 2051 case SAM_STAT_INTERMEDIATE: 2052 case SAM_STAT_INTERMEDIATE_CONDITION_MET: 2053 case SAM_STAT_ACA_ACTIVE: 2054 /* 2055 * who knows? FIXME(eric) 2056 */ 2057 return SUCCESS; 2058 2059 case SAM_STAT_RESERVATION_CONFLICT: 2060 sdev_printk(KERN_INFO, scmd->device, 2061 "reservation conflict\n"); 2062 set_scsi_ml_byte(scmd, SCSIML_STAT_RESV_CONFLICT); 2063 return SUCCESS; /* causes immediate i/o error */ 2064 } 2065 return FAILED; 2066 2067 maybe_retry: 2068 2069 /* we requeue for retry because the error was retryable, and 2070 * the request was not marked fast fail. Note that above, 2071 * even if the request is marked fast fail, we still requeue 2072 * for queue congestion conditions (QUEUE_FULL or BUSY) */ 2073 if (scsi_cmd_retry_allowed(scmd) && !scsi_noretry_cmd(scmd)) { 2074 return NEEDS_RETRY; 2075 } else { 2076 /* 2077 * no more retries - report this one back to upper level. 2078 */ 2079 return SUCCESS; 2080 } 2081 } 2082 2083 static enum rq_end_io_ret eh_lock_door_done(struct request *req, 2084 blk_status_t status) 2085 { 2086 blk_mq_free_request(req); 2087 return RQ_END_IO_NONE; 2088 } 2089 2090 /** 2091 * scsi_eh_lock_door - Prevent medium removal for the specified device 2092 * @sdev: SCSI device to prevent medium removal 2093 * 2094 * Locking: 2095 * We must be called from process context. 2096 * 2097 * Notes: 2098 * We queue up an asynchronous "ALLOW MEDIUM REMOVAL" request on the 2099 * head of the devices request queue, and continue. 2100 */ 2101 static void scsi_eh_lock_door(struct scsi_device *sdev) 2102 { 2103 struct scsi_cmnd *scmd; 2104 struct request *req; 2105 2106 req = scsi_alloc_request(sdev->request_queue, REQ_OP_DRV_IN, 0); 2107 if (IS_ERR(req)) 2108 return; 2109 scmd = blk_mq_rq_to_pdu(req); 2110 2111 scmd->cmnd[0] = ALLOW_MEDIUM_REMOVAL; 2112 scmd->cmnd[1] = 0; 2113 scmd->cmnd[2] = 0; 2114 scmd->cmnd[3] = 0; 2115 scmd->cmnd[4] = SCSI_REMOVAL_PREVENT; 2116 scmd->cmnd[5] = 0; 2117 scmd->cmd_len = COMMAND_SIZE(scmd->cmnd[0]); 2118 scmd->allowed = 5; 2119 2120 req->rq_flags |= RQF_QUIET; 2121 req->timeout = 10 * HZ; 2122 req->end_io = eh_lock_door_done; 2123 2124 blk_execute_rq_nowait(req, true); 2125 } 2126 2127 /** 2128 * scsi_restart_operations - restart io operations to the specified host. 2129 * @shost: Host we are restarting. 2130 * 2131 * Notes: 2132 * When we entered the error handler, we blocked all further i/o to 2133 * this device. we need to 'reverse' this process. 2134 */ 2135 static void scsi_restart_operations(struct Scsi_Host *shost) 2136 { 2137 struct scsi_device *sdev; 2138 unsigned long flags; 2139 2140 /* 2141 * If the door was locked, we need to insert a door lock request 2142 * onto the head of the SCSI request queue for the device. There 2143 * is no point trying to lock the door of an off-line device. 2144 */ 2145 shost_for_each_device(sdev, shost) { 2146 if (scsi_device_online(sdev) && sdev->was_reset && sdev->locked) { 2147 scsi_eh_lock_door(sdev); 2148 sdev->was_reset = 0; 2149 } 2150 } 2151 2152 /* 2153 * next free up anything directly waiting upon the host. this 2154 * will be requests for character device operations, and also for 2155 * ioctls to queued block devices. 2156 */ 2157 SCSI_LOG_ERROR_RECOVERY(3, 2158 shost_printk(KERN_INFO, shost, "waking up host to restart\n")); 2159 2160 spin_lock_irqsave(shost->host_lock, flags); 2161 if (scsi_host_set_state(shost, SHOST_RUNNING)) 2162 if (scsi_host_set_state(shost, SHOST_CANCEL)) 2163 BUG_ON(scsi_host_set_state(shost, SHOST_DEL)); 2164 spin_unlock_irqrestore(shost->host_lock, flags); 2165 2166 wake_up(&shost->host_wait); 2167 2168 /* 2169 * finally we need to re-initiate requests that may be pending. we will 2170 * have had everything blocked while error handling is taking place, and 2171 * now that error recovery is done, we will need to ensure that these 2172 * requests are started. 2173 */ 2174 scsi_run_host_queues(shost); 2175 2176 /* 2177 * if eh is active and host_eh_scheduled is pending we need to re-run 2178 * recovery. we do this check after scsi_run_host_queues() to allow 2179 * everything pent up since the last eh run a chance to make forward 2180 * progress before we sync again. Either we'll immediately re-run 2181 * recovery or scsi_device_unbusy() will wake us again when these 2182 * pending commands complete. 2183 */ 2184 spin_lock_irqsave(shost->host_lock, flags); 2185 if (shost->host_eh_scheduled) 2186 if (scsi_host_set_state(shost, SHOST_RECOVERY)) 2187 WARN_ON(scsi_host_set_state(shost, SHOST_CANCEL_RECOVERY)); 2188 spin_unlock_irqrestore(shost->host_lock, flags); 2189 } 2190 2191 /** 2192 * scsi_eh_ready_devs - check device ready state and recover if not. 2193 * @shost: host to be recovered. 2194 * @work_q: &list_head for pending commands. 2195 * @done_q: &list_head for processed commands. 2196 */ 2197 void scsi_eh_ready_devs(struct Scsi_Host *shost, 2198 struct list_head *work_q, 2199 struct list_head *done_q) 2200 { 2201 if (!scsi_eh_stu(shost, work_q, done_q)) 2202 if (!scsi_eh_bus_device_reset(shost, work_q, done_q)) 2203 if (!scsi_eh_target_reset(shost, work_q, done_q)) 2204 if (!scsi_eh_bus_reset(shost, work_q, done_q)) 2205 if (!scsi_eh_host_reset(shost, work_q, done_q)) 2206 scsi_eh_offline_sdevs(work_q, 2207 done_q); 2208 } 2209 EXPORT_SYMBOL_GPL(scsi_eh_ready_devs); 2210 2211 /** 2212 * scsi_eh_flush_done_q - finish processed commands or retry them. 2213 * @done_q: list_head of processed commands. 2214 */ 2215 void scsi_eh_flush_done_q(struct list_head *done_q) 2216 { 2217 struct scsi_cmnd *scmd, *next; 2218 2219 list_for_each_entry_safe(scmd, next, done_q, eh_entry) { 2220 struct scsi_device *sdev = scmd->device; 2221 2222 list_del_init(&scmd->eh_entry); 2223 if (scsi_device_online(sdev) && !scsi_noretry_cmd(scmd) && 2224 scsi_cmd_retry_allowed(scmd) && 2225 scsi_eh_should_retry_cmd(scmd)) { 2226 SCSI_LOG_ERROR_RECOVERY(3, 2227 scmd_printk(KERN_INFO, scmd, 2228 "%s: flush retry cmd\n", 2229 current->comm)); 2230 scsi_queue_insert(scmd, SCSI_MLQUEUE_EH_RETRY); 2231 blk_mq_kick_requeue_list(sdev->request_queue); 2232 } else { 2233 /* 2234 * If just we got sense for the device (called 2235 * scsi_eh_get_sense), scmd->result is already 2236 * set, do not set DID_TIME_OUT. 2237 */ 2238 if (!scmd->result && 2239 !(scmd->flags & SCMD_FORCE_EH_SUCCESS)) 2240 scmd->result |= (DID_TIME_OUT << 16); 2241 SCSI_LOG_ERROR_RECOVERY(3, 2242 scmd_printk(KERN_INFO, scmd, 2243 "%s: flush finish cmd\n", 2244 current->comm)); 2245 scsi_finish_command(scmd); 2246 } 2247 } 2248 } 2249 EXPORT_SYMBOL(scsi_eh_flush_done_q); 2250 2251 /** 2252 * scsi_unjam_host - Attempt to fix a host which has a cmd that failed. 2253 * @shost: Host to unjam. 2254 * 2255 * Notes: 2256 * When we come in here, we *know* that all commands on the bus have 2257 * either completed, failed or timed out. we also know that no further 2258 * commands are being sent to the host, so things are relatively quiet 2259 * and we have freedom to fiddle with things as we wish. 2260 * 2261 * This is only the *default* implementation. it is possible for 2262 * individual drivers to supply their own version of this function, and 2263 * if the maintainer wishes to do this, it is strongly suggested that 2264 * this function be taken as a template and modified. this function 2265 * was designed to correctly handle problems for about 95% of the 2266 * different cases out there, and it should always provide at least a 2267 * reasonable amount of error recovery. 2268 * 2269 * Any command marked 'failed' or 'timeout' must eventually have 2270 * scsi_finish_cmd() called for it. we do all of the retry stuff 2271 * here, so when we restart the host after we return it should have an 2272 * empty queue. 2273 */ 2274 static void scsi_unjam_host(struct Scsi_Host *shost) 2275 { 2276 unsigned long flags; 2277 LIST_HEAD(eh_work_q); 2278 LIST_HEAD(eh_done_q); 2279 2280 spin_lock_irqsave(shost->host_lock, flags); 2281 list_splice_init(&shost->eh_cmd_q, &eh_work_q); 2282 spin_unlock_irqrestore(shost->host_lock, flags); 2283 2284 SCSI_LOG_ERROR_RECOVERY(1, scsi_eh_prt_fail_stats(shost, &eh_work_q)); 2285 2286 if (!scsi_eh_get_sense(&eh_work_q, &eh_done_q)) 2287 scsi_eh_ready_devs(shost, &eh_work_q, &eh_done_q); 2288 2289 spin_lock_irqsave(shost->host_lock, flags); 2290 if (shost->eh_deadline != -1) 2291 shost->last_reset = 0; 2292 spin_unlock_irqrestore(shost->host_lock, flags); 2293 scsi_eh_flush_done_q(&eh_done_q); 2294 } 2295 2296 /** 2297 * scsi_error_handler - SCSI error handler thread 2298 * @data: Host for which we are running. 2299 * 2300 * Notes: 2301 * This is the main error handling loop. This is run as a kernel thread 2302 * for every SCSI host and handles all error handling activity. 2303 */ 2304 int scsi_error_handler(void *data) 2305 { 2306 struct Scsi_Host *shost = data; 2307 2308 /* 2309 * We use TASK_INTERRUPTIBLE so that the thread is not 2310 * counted against the load average as a running process. 2311 * We never actually get interrupted because kthread_run 2312 * disables signal delivery for the created thread. 2313 */ 2314 while (true) { 2315 /* 2316 * The sequence in kthread_stop() sets the stop flag first 2317 * then wakes the process. To avoid missed wakeups, the task 2318 * should always be in a non running state before the stop 2319 * flag is checked 2320 */ 2321 set_current_state(TASK_INTERRUPTIBLE); 2322 if (kthread_should_stop()) 2323 break; 2324 2325 if ((shost->host_failed == 0 && shost->host_eh_scheduled == 0) || 2326 shost->host_failed != scsi_host_busy(shost)) { 2327 SCSI_LOG_ERROR_RECOVERY(1, 2328 shost_printk(KERN_INFO, shost, 2329 "scsi_eh_%d: sleeping\n", 2330 shost->host_no)); 2331 schedule(); 2332 continue; 2333 } 2334 2335 __set_current_state(TASK_RUNNING); 2336 SCSI_LOG_ERROR_RECOVERY(1, 2337 shost_printk(KERN_INFO, shost, 2338 "scsi_eh_%d: waking up %d/%d/%d\n", 2339 shost->host_no, shost->host_eh_scheduled, 2340 shost->host_failed, 2341 scsi_host_busy(shost))); 2342 2343 /* 2344 * We have a host that is failing for some reason. Figure out 2345 * what we need to do to get it up and online again (if we can). 2346 * If we fail, we end up taking the thing offline. 2347 */ 2348 if (!shost->eh_noresume && scsi_autopm_get_host(shost) != 0) { 2349 SCSI_LOG_ERROR_RECOVERY(1, 2350 shost_printk(KERN_ERR, shost, 2351 "scsi_eh_%d: unable to autoresume\n", 2352 shost->host_no)); 2353 continue; 2354 } 2355 2356 if (shost->transportt->eh_strategy_handler) 2357 shost->transportt->eh_strategy_handler(shost); 2358 else 2359 scsi_unjam_host(shost); 2360 2361 /* All scmds have been handled */ 2362 shost->host_failed = 0; 2363 2364 /* 2365 * Note - if the above fails completely, the action is to take 2366 * individual devices offline and flush the queue of any 2367 * outstanding requests that may have been pending. When we 2368 * restart, we restart any I/O to any other devices on the bus 2369 * which are still online. 2370 */ 2371 scsi_restart_operations(shost); 2372 if (!shost->eh_noresume) 2373 scsi_autopm_put_host(shost); 2374 } 2375 __set_current_state(TASK_RUNNING); 2376 2377 SCSI_LOG_ERROR_RECOVERY(1, 2378 shost_printk(KERN_INFO, shost, 2379 "Error handler scsi_eh_%d exiting\n", 2380 shost->host_no)); 2381 shost->ehandler = NULL; 2382 return 0; 2383 } 2384 2385 /** 2386 * scsi_report_bus_reset() - report bus reset observed 2387 * 2388 * Utility function used by low-level drivers to report that 2389 * they have observed a bus reset on the bus being handled. 2390 * 2391 * @shost: Host in question 2392 * @channel: channel on which reset was observed. 2393 * 2394 * Returns: Nothing 2395 * 2396 * Lock status: Host lock must be held. 2397 * 2398 * Notes: This only needs to be called if the reset is one which 2399 * originates from an unknown location. Resets originated 2400 * by the mid-level itself don't need to call this, but there 2401 * should be no harm. 2402 * 2403 * The main purpose of this is to make sure that a CHECK_CONDITION 2404 * is properly treated. 2405 */ 2406 void scsi_report_bus_reset(struct Scsi_Host *shost, int channel) 2407 { 2408 struct scsi_device *sdev; 2409 2410 __shost_for_each_device(sdev, shost) { 2411 if (channel == sdev_channel(sdev)) 2412 __scsi_report_device_reset(sdev, NULL); 2413 } 2414 } 2415 EXPORT_SYMBOL(scsi_report_bus_reset); 2416 2417 /** 2418 * scsi_report_device_reset() - report device reset observed 2419 * 2420 * Utility function used by low-level drivers to report that 2421 * they have observed a device reset on the device being handled. 2422 * 2423 * @shost: Host in question 2424 * @channel: channel on which reset was observed 2425 * @target: target on which reset was observed 2426 * 2427 * Returns: Nothing 2428 * 2429 * Lock status: Host lock must be held 2430 * 2431 * Notes: This only needs to be called if the reset is one which 2432 * originates from an unknown location. Resets originated 2433 * by the mid-level itself don't need to call this, but there 2434 * should be no harm. 2435 * 2436 * The main purpose of this is to make sure that a CHECK_CONDITION 2437 * is properly treated. 2438 */ 2439 void scsi_report_device_reset(struct Scsi_Host *shost, int channel, int target) 2440 { 2441 struct scsi_device *sdev; 2442 2443 __shost_for_each_device(sdev, shost) { 2444 if (channel == sdev_channel(sdev) && 2445 target == sdev_id(sdev)) 2446 __scsi_report_device_reset(sdev, NULL); 2447 } 2448 } 2449 EXPORT_SYMBOL(scsi_report_device_reset); 2450 2451 /** 2452 * scsi_ioctl_reset: explicitly reset a host/bus/target/device 2453 * @dev: scsi_device to operate on 2454 * @arg: reset type (see sg.h) 2455 */ 2456 int 2457 scsi_ioctl_reset(struct scsi_device *dev, int __user *arg) 2458 { 2459 struct scsi_cmnd *scmd; 2460 struct Scsi_Host *shost = dev->host; 2461 struct request *rq; 2462 unsigned long flags; 2463 int error = 0, val; 2464 enum scsi_disposition rtn; 2465 2466 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO)) 2467 return -EACCES; 2468 2469 error = get_user(val, arg); 2470 if (error) 2471 return error; 2472 2473 if (scsi_autopm_get_host(shost) < 0) 2474 return -EIO; 2475 2476 error = -EIO; 2477 rq = kzalloc(sizeof(struct request) + sizeof(struct scsi_cmnd) + 2478 shost->hostt->cmd_size, GFP_KERNEL); 2479 if (!rq) 2480 goto out_put_autopm_host; 2481 blk_rq_init(NULL, rq); 2482 2483 scmd = (struct scsi_cmnd *)(rq + 1); 2484 scsi_init_command(dev, scmd); 2485 2486 scmd->submitter = SUBMITTED_BY_SCSI_RESET_IOCTL; 2487 scmd->flags |= SCMD_LAST; 2488 memset(&scmd->sdb, 0, sizeof(scmd->sdb)); 2489 2490 scmd->cmd_len = 0; 2491 2492 scmd->sc_data_direction = DMA_BIDIRECTIONAL; 2493 2494 spin_lock_irqsave(shost->host_lock, flags); 2495 shost->tmf_in_progress = 1; 2496 spin_unlock_irqrestore(shost->host_lock, flags); 2497 2498 switch (val & ~SG_SCSI_RESET_NO_ESCALATE) { 2499 case SG_SCSI_RESET_NOTHING: 2500 rtn = SUCCESS; 2501 break; 2502 case SG_SCSI_RESET_DEVICE: 2503 rtn = scsi_try_bus_device_reset(scmd); 2504 if (rtn == SUCCESS || (val & SG_SCSI_RESET_NO_ESCALATE)) 2505 break; 2506 fallthrough; 2507 case SG_SCSI_RESET_TARGET: 2508 rtn = scsi_try_target_reset(scmd); 2509 if (rtn == SUCCESS || (val & SG_SCSI_RESET_NO_ESCALATE)) 2510 break; 2511 fallthrough; 2512 case SG_SCSI_RESET_BUS: 2513 rtn = scsi_try_bus_reset(scmd); 2514 if (rtn == SUCCESS || (val & SG_SCSI_RESET_NO_ESCALATE)) 2515 break; 2516 fallthrough; 2517 case SG_SCSI_RESET_HOST: 2518 rtn = scsi_try_host_reset(scmd); 2519 if (rtn == SUCCESS) 2520 break; 2521 fallthrough; 2522 default: 2523 rtn = FAILED; 2524 break; 2525 } 2526 2527 error = (rtn == SUCCESS) ? 0 : -EIO; 2528 2529 spin_lock_irqsave(shost->host_lock, flags); 2530 shost->tmf_in_progress = 0; 2531 spin_unlock_irqrestore(shost->host_lock, flags); 2532 2533 /* 2534 * be sure to wake up anyone who was sleeping or had their queue 2535 * suspended while we performed the TMF. 2536 */ 2537 SCSI_LOG_ERROR_RECOVERY(3, 2538 shost_printk(KERN_INFO, shost, 2539 "waking up host to restart after TMF\n")); 2540 2541 wake_up(&shost->host_wait); 2542 scsi_run_host_queues(shost); 2543 2544 kfree(rq); 2545 2546 out_put_autopm_host: 2547 scsi_autopm_put_host(shost); 2548 return error; 2549 } 2550 2551 bool scsi_command_normalize_sense(const struct scsi_cmnd *cmd, 2552 struct scsi_sense_hdr *sshdr) 2553 { 2554 return scsi_normalize_sense(cmd->sense_buffer, 2555 SCSI_SENSE_BUFFERSIZE, sshdr); 2556 } 2557 EXPORT_SYMBOL(scsi_command_normalize_sense); 2558 2559 /** 2560 * scsi_get_sense_info_fld - get information field from sense data (either fixed or descriptor format) 2561 * @sense_buffer: byte array of sense data 2562 * @sb_len: number of valid bytes in sense_buffer 2563 * @info_out: pointer to 64 integer where 8 or 4 byte information 2564 * field will be placed if found. 2565 * 2566 * Return value: 2567 * true if information field found, false if not found. 2568 */ 2569 bool scsi_get_sense_info_fld(const u8 *sense_buffer, int sb_len, 2570 u64 *info_out) 2571 { 2572 const u8 * ucp; 2573 2574 if (sb_len < 7) 2575 return false; 2576 switch (sense_buffer[0] & 0x7f) { 2577 case 0x70: 2578 case 0x71: 2579 if (sense_buffer[0] & 0x80) { 2580 *info_out = get_unaligned_be32(&sense_buffer[3]); 2581 return true; 2582 } 2583 return false; 2584 case 0x72: 2585 case 0x73: 2586 ucp = scsi_sense_desc_find(sense_buffer, sb_len, 2587 0 /* info desc */); 2588 if (ucp && (0xa == ucp[1])) { 2589 *info_out = get_unaligned_be64(&ucp[4]); 2590 return true; 2591 } 2592 return false; 2593 default: 2594 return false; 2595 } 2596 } 2597 EXPORT_SYMBOL(scsi_get_sense_info_fld); 2598