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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 ([email protected])
12 *
13 * Forward port of Russell King's ([email protected]) changes and
14 * minor cleanups.
15 * September 30, 2002 Mike Anderson ([email protected])
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
60static int scsi_eh_try_stu(struct scsi_cmnd *scmd);
61static enum scsi_disposition scsi_try_to_abort_cmd(const struct scsi_host_template *,
62 struct scsi_cmnd *);
63
64void 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
76void scsi_rcu_eh_wakeup(struct work_struct *work)
77{
78 struct Scsi_Host *shost = container_of(work, struct Scsi_Host, eh_work);
79 unsigned long flags;
80 unsigned int busy;
81
82 /*
83 * Ensure any running scsi_dec_host_busy has completed its rcu section
84 * so changes to host state and host_eh_scheduled are visible to all
85 * future calls of scsi_dec_host_busy
86 */
87 synchronize_rcu();
88
89 busy = scsi_host_busy(shost);
90
91 spin_lock_irqsave(shost->host_lock, flags);
92 scsi_eh_wakeup(shost, busy);
93 spin_unlock_irqrestore(shost->host_lock, flags);
94}
95
96/**
97 * scsi_schedule_eh - schedule EH for SCSI host
98 * @shost: SCSI host to invoke error handling on.
99 *
100 * Schedule SCSI EH without scmd.
101 */
102void scsi_schedule_eh(struct Scsi_Host *shost)
103{
104 unsigned long flags;
105
106 spin_lock_irqsave(shost->host_lock, flags);
107
108 if (scsi_host_set_state(shost, SHOST_RECOVERY) == 0 ||
109 scsi_host_set_state(shost, SHOST_CANCEL_RECOVERY) == 0) {
110 shost->host_eh_scheduled++;
111 queue_work(shost->tmf_work_q, &shost->eh_work);
112 }
113
114 spin_unlock_irqrestore(shost->host_lock, flags);
115}
116EXPORT_SYMBOL_GPL(scsi_schedule_eh);
117
118static int scsi_host_eh_past_deadline(struct Scsi_Host *shost)
119{
120 if (!shost->last_reset || shost->eh_deadline == -1)
121 return 0;
122
123 /*
124 * 32bit accesses are guaranteed to be atomic
125 * (on all supported architectures), so instead
126 * of using a spinlock we can as well double check
127 * if eh_deadline has been set to 'off' during the
128 * time_before call.
129 */
130 if (time_before(jiffies, shost->last_reset + shost->eh_deadline) &&
131 shost->eh_deadline > -1)
132 return 0;
133
134 return 1;
135}
136
137static bool scsi_cmd_retry_allowed(struct scsi_cmnd *cmd)
138{
139 if (cmd->allowed == SCSI_CMD_RETRIES_NO_LIMIT)
140 return true;
141
142 return ++cmd->retries <= cmd->allowed;
143}
144
145static bool scsi_eh_should_retry_cmd(struct scsi_cmnd *cmd)
146{
147 struct scsi_device *sdev = cmd->device;
148 struct Scsi_Host *host = sdev->host;
149
150 if (host->hostt->eh_should_retry_cmd)
151 return host->hostt->eh_should_retry_cmd(cmd);
152
153 return true;
154}
155
156/**
157 * scmd_eh_abort_handler - Handle command aborts
158 * @work: command to be aborted.
159 *
160 * Note: this function must be called only for a command that has timed out.
161 * Because the block layer marks a request as complete before it calls
162 * scsi_timeout(), a .scsi_done() call from the LLD for a command that has
163 * timed out do not have any effect. Hence it is safe to call
164 * scsi_finish_command() from this function.
165 */
166void
167scmd_eh_abort_handler(struct work_struct *work)
168{
169 struct scsi_cmnd *scmd =
170 container_of(work, struct scsi_cmnd, abort_work.work);
171 struct scsi_device *sdev = scmd->device;
172 struct Scsi_Host *shost = sdev->host;
173 enum scsi_disposition rtn;
174 unsigned long flags;
175
176 if (scsi_host_eh_past_deadline(shost)) {
177 SCSI_LOG_ERROR_RECOVERY(3,
178 scmd_printk(KERN_INFO, scmd,
179 "eh timeout, not aborting\n"));
180 goto out;
181 }
182
183 SCSI_LOG_ERROR_RECOVERY(3,
184 scmd_printk(KERN_INFO, scmd,
185 "aborting command\n"));
186 rtn = scsi_try_to_abort_cmd(shost->hostt, scmd);
187 if (rtn != SUCCESS) {
188 SCSI_LOG_ERROR_RECOVERY(3,
189 scmd_printk(KERN_INFO, scmd,
190 "cmd abort %s\n",
191 (rtn == FAST_IO_FAIL) ?
192 "not send" : "failed"));
193 goto out;
194 }
195 set_host_byte(scmd, DID_TIME_OUT);
196 if (scsi_host_eh_past_deadline(shost)) {
197 SCSI_LOG_ERROR_RECOVERY(3,
198 scmd_printk(KERN_INFO, scmd,
199 "eh timeout, not retrying "
200 "aborted command\n"));
201 goto out;
202 }
203
204 spin_lock_irqsave(shost->host_lock, flags);
205 list_del_init(&scmd->eh_entry);
206
207 /*
208 * If the abort succeeds, and there is no further
209 * EH action, clear the ->last_reset time.
210 */
211 if (list_empty(&shost->eh_abort_list) &&
212 list_empty(&shost->eh_cmd_q))
213 if (shost->eh_deadline != -1)
214 shost->last_reset = 0;
215
216 spin_unlock_irqrestore(shost->host_lock, flags);
217
218 if (!scsi_noretry_cmd(scmd) &&
219 scsi_cmd_retry_allowed(scmd) &&
220 scsi_eh_should_retry_cmd(scmd)) {
221 SCSI_LOG_ERROR_RECOVERY(3,
222 scmd_printk(KERN_WARNING, scmd,
223 "retry aborted command\n"));
224 scsi_queue_insert(scmd, SCSI_MLQUEUE_EH_RETRY);
225 } else {
226 SCSI_LOG_ERROR_RECOVERY(3,
227 scmd_printk(KERN_WARNING, scmd,
228 "finish aborted command\n"));
229 scsi_finish_command(scmd);
230 }
231 return;
232
233out:
234 spin_lock_irqsave(shost->host_lock, flags);
235 list_del_init(&scmd->eh_entry);
236 spin_unlock_irqrestore(shost->host_lock, flags);
237
238 scsi_eh_scmd_add(scmd);
239}
240
241/**
242 * scsi_abort_command - schedule a command abort
243 * @scmd: scmd to abort.
244 *
245 * We only need to abort commands after a command timeout
246 */
247static int
248scsi_abort_command(struct scsi_cmnd *scmd)
249{
250 struct scsi_device *sdev = scmd->device;
251 struct Scsi_Host *shost = sdev->host;
252 unsigned long flags;
253
254 if (!shost->hostt->eh_abort_handler) {
255 /* No abort handler, fail command directly */
256 return FAILED;
257 }
258
259 if (scmd->eh_eflags & SCSI_EH_ABORT_SCHEDULED) {
260 /*
261 * Retry after abort failed, escalate to next level.
262 */
263 SCSI_LOG_ERROR_RECOVERY(3,
264 scmd_printk(KERN_INFO, scmd,
265 "previous abort failed\n"));
266 BUG_ON(delayed_work_pending(&scmd->abort_work));
267 return FAILED;
268 }
269
270 spin_lock_irqsave(shost->host_lock, flags);
271 if (shost->eh_deadline != -1 && !shost->last_reset)
272 shost->last_reset = jiffies;
273 BUG_ON(!list_empty(&scmd->eh_entry));
274 list_add_tail(&scmd->eh_entry, &shost->eh_abort_list);
275 spin_unlock_irqrestore(shost->host_lock, flags);
276
277 scmd->eh_eflags |= SCSI_EH_ABORT_SCHEDULED;
278 SCSI_LOG_ERROR_RECOVERY(3,
279 scmd_printk(KERN_INFO, scmd, "abort scheduled\n"));
280 queue_delayed_work(shost->tmf_work_q, &scmd->abort_work, HZ / 100);
281 return SUCCESS;
282}
283
284/**
285 * scsi_eh_reset - call into ->eh_action to reset internal counters
286 * @scmd: scmd to run eh on.
287 *
288 * The scsi driver might be carrying internal state about the
289 * devices, so we need to call into the driver to reset the
290 * internal state once the error handler is started.
291 */
292static void scsi_eh_reset(struct scsi_cmnd *scmd)
293{
294 if (!blk_rq_is_passthrough(scsi_cmd_to_rq(scmd))) {
295 struct scsi_driver *sdrv = scsi_cmd_to_driver(scmd);
296 if (sdrv->eh_reset)
297 sdrv->eh_reset(scmd);
298 }
299}
300
301static void scsi_eh_inc_host_failed(struct rcu_head *head)
302{
303 struct scsi_cmnd *scmd = container_of(head, typeof(*scmd), rcu);
304 struct Scsi_Host *shost = scmd->device->host;
305 unsigned int busy;
306 unsigned long flags;
307
308 spin_lock_irqsave(shost->host_lock, flags);
309 shost->host_failed++;
310 spin_unlock_irqrestore(shost->host_lock, flags);
311 /*
312 * The counting of busy requests needs to occur after adding to
313 * host_failed or after the lock acquire for adding to host_failed
314 * to prevent a race with host unbusy and missing an eh wakeup.
315 */
316 busy = scsi_host_busy(shost);
317
318 spin_lock_irqsave(shost->host_lock, flags);
319 scsi_eh_wakeup(shost, busy);
320 spin_unlock_irqrestore(shost->host_lock, flags);
321}
322
323/**
324 * scsi_eh_scmd_add - add scsi cmd to error handling.
325 * @scmd: scmd to run eh on.
326 */
327void scsi_eh_scmd_add(struct scsi_cmnd *scmd)
328{
329 struct Scsi_Host *shost = scmd->device->host;
330 unsigned long flags;
331 int ret;
332
333 WARN_ON_ONCE(!shost->ehandler);
334 WARN_ON_ONCE(!test_bit(SCMD_STATE_INFLIGHT, &scmd->state));
335
336 spin_lock_irqsave(shost->host_lock, flags);
337 if (scsi_host_set_state(shost, SHOST_RECOVERY)) {
338 ret = scsi_host_set_state(shost, SHOST_CANCEL_RECOVERY);
339 WARN_ON_ONCE(ret);
340 }
341 if (shost->eh_deadline != -1 && !shost->last_reset)
342 shost->last_reset = jiffies;
343
344 scsi_eh_reset(scmd);
345 list_add_tail(&scmd->eh_entry, &shost->eh_cmd_q);
346 spin_unlock_irqrestore(shost->host_lock, flags);
347 /*
348 * Ensure that all tasks observe the host state change before the
349 * host_failed change.
350 */
351 call_rcu_hurry(&scmd->rcu, scsi_eh_inc_host_failed);
352}
353
354/**
355 * scsi_timeout - Timeout function for normal scsi commands.
356 * @req: request that is timing out.
357 *
358 * Notes:
359 * We do not need to lock this. There is the potential for a race
360 * only in that the normal completion handling might run, but if the
361 * normal completion function determines that the timer has already
362 * fired, then it mustn't do anything.
363 */
364enum blk_eh_timer_return scsi_timeout(struct request *req)
365{
366 struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(req);
367 struct Scsi_Host *host = scmd->device->host;
368
369 trace_scsi_dispatch_cmd_timeout(scmd);
370 scsi_log_completion(scmd, TIMEOUT_ERROR);
371
372 atomic_inc(&scmd->device->iotmo_cnt);
373 if (host->eh_deadline != -1 && !host->last_reset)
374 host->last_reset = jiffies;
375
376 if (host->hostt->eh_timed_out) {
377 switch (host->hostt->eh_timed_out(scmd)) {
378 case SCSI_EH_DONE:
379 return BLK_EH_DONE;
380 case SCSI_EH_RESET_TIMER:
381 return BLK_EH_RESET_TIMER;
382 case SCSI_EH_NOT_HANDLED:
383 break;
384 }
385 }
386
387 /*
388 * If scsi_done() has already set SCMD_STATE_COMPLETE, do not modify
389 * *scmd.
390 */
391 if (test_and_set_bit(SCMD_STATE_COMPLETE, &scmd->state))
392 return BLK_EH_DONE;
393 atomic_inc(&scmd->device->iodone_cnt);
394 if (scsi_abort_command(scmd) != SUCCESS) {
395 set_host_byte(scmd, DID_TIME_OUT);
396 scsi_eh_scmd_add(scmd);
397 }
398
399 return BLK_EH_DONE;
400}
401
402/**
403 * scsi_block_when_processing_errors - Prevent cmds from being queued.
404 * @sdev: Device on which we are performing recovery.
405 *
406 * Description:
407 * We block until the host is out of error recovery, and then check to
408 * see whether the host or the device is offline.
409 *
410 * Return value:
411 * 0 when dev was taken offline by error recovery. 1 OK to proceed.
412 */
413int scsi_block_when_processing_errors(struct scsi_device *sdev)
414{
415 int online;
416
417 wait_event(sdev->host->host_wait, !scsi_host_in_recovery(sdev->host));
418
419 online = scsi_device_online(sdev);
420
421 return online;
422}
423EXPORT_SYMBOL(scsi_block_when_processing_errors);
424
425#ifdef CONFIG_SCSI_LOGGING
426/**
427 * scsi_eh_prt_fail_stats - Log info on failures.
428 * @shost: scsi host being recovered.
429 * @work_q: Queue of scsi cmds to process.
430 */
431static inline void scsi_eh_prt_fail_stats(struct Scsi_Host *shost,
432 struct list_head *work_q)
433{
434 struct scsi_cmnd *scmd;
435 struct scsi_device *sdev;
436 int total_failures = 0;
437 int cmd_failed = 0;
438 int cmd_cancel = 0;
439 int devices_failed = 0;
440
441 shost_for_each_device(sdev, shost) {
442 list_for_each_entry(scmd, work_q, eh_entry) {
443 if (scmd->device == sdev) {
444 ++total_failures;
445 if (scmd->eh_eflags & SCSI_EH_ABORT_SCHEDULED)
446 ++cmd_cancel;
447 else
448 ++cmd_failed;
449 }
450 }
451
452 if (cmd_cancel || cmd_failed) {
453 SCSI_LOG_ERROR_RECOVERY(3,
454 shost_printk(KERN_INFO, shost,
455 "%s: cmds failed: %d, cancel: %d\n",
456 __func__, cmd_failed,
457 cmd_cancel));
458 cmd_cancel = 0;
459 cmd_failed = 0;
460 ++devices_failed;
461 }
462 }
463
464 SCSI_LOG_ERROR_RECOVERY(2, shost_printk(KERN_INFO, shost,
465 "Total of %d commands on %d"
466 " devices require eh work\n",
467 total_failures, devices_failed));
468}
469#endif
470
471 /**
472 * scsi_report_lun_change - Set flag on all *other* devices on the same target
473 * to indicate that a UNIT ATTENTION is expected.
474 * @sdev: Device reporting the UNIT ATTENTION
475 */
476static void scsi_report_lun_change(struct scsi_device *sdev)
477{
478 sdev->sdev_target->expecting_lun_change = 1;
479}
480
481/**
482 * scsi_report_sense - Examine scsi sense information and log messages for
483 * certain conditions, also issue uevents for some of them.
484 * @sdev: Device reporting the sense code
485 * @sshdr: sshdr to be examined
486 */
487static void scsi_report_sense(struct scsi_device *sdev,
488 struct scsi_sense_hdr *sshdr)
489{
490 enum scsi_device_event evt_type = SDEV_EVT_MAXBITS; /* i.e. none */
491
492 if (sshdr->sense_key == UNIT_ATTENTION) {
493 if (sshdr->asc == 0x3f && sshdr->ascq == 0x03) {
494 evt_type = SDEV_EVT_INQUIRY_CHANGE_REPORTED;
495 sdev_printk(KERN_WARNING, sdev,
496 "Inquiry data has changed");
497 } else if (sshdr->asc == 0x3f && sshdr->ascq == 0x0e) {
498 evt_type = SDEV_EVT_LUN_CHANGE_REPORTED;
499 scsi_report_lun_change(sdev);
500 sdev_printk(KERN_WARNING, sdev,
501 "LUN assignments on this target have "
502 "changed. The Linux SCSI layer does not "
503 "automatically remap LUN assignments.\n");
504 } else if (sshdr->asc == 0x3f)
505 sdev_printk(KERN_WARNING, sdev,
506 "Operating parameters on this target have "
507 "changed. The Linux SCSI layer does not "
508 "automatically adjust these parameters.\n");
509
510 if (sshdr->asc == 0x38 && sshdr->ascq == 0x07) {
511 evt_type = SDEV_EVT_SOFT_THRESHOLD_REACHED_REPORTED;
512 sdev_printk(KERN_WARNING, sdev,
513 "Warning! Received an indication that the "
514 "LUN reached a thin provisioning soft "
515 "threshold.\n");
516 }
517
518 if (sshdr->asc == 0x29) {
519 evt_type = SDEV_EVT_POWER_ON_RESET_OCCURRED;
520 /*
521 * Do not print message if it is an expected side-effect
522 * of runtime PM.
523 */
524 if (!sdev->silence_suspend)
525 sdev_printk(KERN_WARNING, sdev,
526 "Power-on or device reset occurred\n");
527 }
528
529 if (sshdr->asc == 0x2a && sshdr->ascq == 0x01) {
530 evt_type = SDEV_EVT_MODE_PARAMETER_CHANGE_REPORTED;
531 sdev_printk(KERN_WARNING, sdev,
532 "Mode parameters changed");
533 } else if (sshdr->asc == 0x2a && sshdr->ascq == 0x06) {
534 evt_type = SDEV_EVT_ALUA_STATE_CHANGE_REPORTED;
535 sdev_printk(KERN_WARNING, sdev,
536 "Asymmetric access state changed");
537 } else if (sshdr->asc == 0x2a && sshdr->ascq == 0x09) {
538 evt_type = SDEV_EVT_CAPACITY_CHANGE_REPORTED;
539 sdev_printk(KERN_WARNING, sdev,
540 "Capacity data has changed");
541 } else if (sshdr->asc == 0x2a)
542 sdev_printk(KERN_WARNING, sdev,
543 "Parameters changed");
544 }
545
546 if (evt_type != SDEV_EVT_MAXBITS) {
547 set_bit(evt_type, sdev->pending_events);
548 schedule_work(&sdev->event_work);
549 }
550}
551
552static inline void set_scsi_ml_byte(struct scsi_cmnd *cmd, u8 status)
553{
554 cmd->result = (cmd->result & 0xffff00ff) | (status << 8);
555}
556
557/**
558 * scsi_check_sense - Examine scsi cmd sense
559 * @scmd: Cmd to have sense checked.
560 *
561 * Return value:
562 * SUCCESS or FAILED or NEEDS_RETRY or ADD_TO_MLQUEUE
563 *
564 * Notes:
565 * When a deferred error is detected the current command has
566 * not been executed and needs retrying.
567 */
568enum scsi_disposition scsi_check_sense(struct scsi_cmnd *scmd)
569{
570 struct request *req = scsi_cmd_to_rq(scmd);
571 struct scsi_device *sdev = scmd->device;
572 struct scsi_sense_hdr sshdr;
573
574 if (! scsi_command_normalize_sense(scmd, &sshdr))
575 return FAILED; /* no valid sense data */
576
577 scsi_report_sense(sdev, &sshdr);
578
579 if (sshdr.sense_key == UNIT_ATTENTION) {
580 /*
581 * Increment the counters for Power on/Reset or New Media so
582 * that all ULDs interested in these can see that those have
583 * happened, even if someone else gets the sense data.
584 */
585 if (sshdr.asc == 0x28)
586 atomic_inc(&sdev->ua_new_media_ctr);
587 else if (sshdr.asc == 0x29)
588 atomic_inc(&sdev->ua_por_ctr);
589 }
590
591 if (scsi_sense_is_deferred(&sshdr))
592 return NEEDS_RETRY;
593
594 if (sdev->handler && sdev->handler->check_sense) {
595 enum scsi_disposition rc;
596
597 rc = sdev->handler->check_sense(sdev, &sshdr);
598 if (rc != SCSI_RETURN_NOT_HANDLED)
599 return rc;
600 /* handler does not care. Drop down to default handling */
601 }
602
603 if (scmd->cmnd[0] == TEST_UNIT_READY &&
604 scmd->submitter != SUBMITTED_BY_SCSI_ERROR_HANDLER)
605 /*
606 * nasty: for mid-layer issued TURs, we need to return the
607 * actual sense data without any recovery attempt. For eh
608 * issued ones, we need to try to recover and interpret
609 */
610 return SUCCESS;
611
612 /*
613 * Previous logic looked for FILEMARK, EOM or ILI which are
614 * mainly associated with tapes and returned SUCCESS.
615 */
616 if (sshdr.response_code == 0x70) {
617 /* fixed format */
618 if (scmd->sense_buffer[2] & 0xe0)
619 return SUCCESS;
620 } else {
621 /*
622 * descriptor format: look for "stream commands sense data
623 * descriptor" (see SSC-3). Assume single sense data
624 * descriptor. Ignore ILI from SBC-2 READ LONG and WRITE LONG.
625 */
626 if ((sshdr.additional_length > 3) &&
627 (scmd->sense_buffer[8] == 0x4) &&
628 (scmd->sense_buffer[11] & 0xe0))
629 return SUCCESS;
630 }
631
632 switch (sshdr.sense_key) {
633 case NO_SENSE:
634 return SUCCESS;
635 case RECOVERED_ERROR:
636 return /* soft_error */ SUCCESS;
637
638 case ABORTED_COMMAND:
639 if (sshdr.asc == 0x10) /* DIF */
640 return SUCCESS;
641
642 /*
643 * Check aborts due to command duration limit policy:
644 * ABORTED COMMAND additional sense code with the
645 * COMMAND TIMEOUT BEFORE PROCESSING or
646 * COMMAND TIMEOUT DURING PROCESSING or
647 * COMMAND TIMEOUT DURING PROCESSING DUE TO ERROR RECOVERY
648 * additional sense code qualifiers.
649 */
650 if (sshdr.asc == 0x2e &&
651 sshdr.ascq >= 0x01 && sshdr.ascq <= 0x03) {
652 set_scsi_ml_byte(scmd, SCSIML_STAT_DL_TIMEOUT);
653 req->cmd_flags |= REQ_FAILFAST_DEV;
654 req->rq_flags |= RQF_QUIET;
655 return SUCCESS;
656 }
657
658 if (sshdr.asc == 0x44 && sdev->sdev_bflags & BLIST_RETRY_ITF)
659 return ADD_TO_MLQUEUE;
660 if (sshdr.asc == 0xc1 && sshdr.ascq == 0x01 &&
661 sdev->sdev_bflags & BLIST_RETRY_ASC_C1)
662 return ADD_TO_MLQUEUE;
663
664 return NEEDS_RETRY;
665 case NOT_READY:
666 case UNIT_ATTENTION:
667 /*
668 * if we are expecting a cc/ua because of a bus reset that we
669 * performed, treat this just as a retry. otherwise this is
670 * information that we should pass up to the upper-level driver
671 * so that we can deal with it there.
672 */
673 if (scmd->device->expecting_cc_ua) {
674 /*
675 * Because some device does not queue unit
676 * attentions correctly, we carefully check
677 * additional sense code and qualifier so as
678 * not to squash media change unit attention.
679 */
680 if (sshdr.asc != 0x28 || sshdr.ascq != 0x00) {
681 scmd->device->expecting_cc_ua = 0;
682 return NEEDS_RETRY;
683 }
684 }
685 /*
686 * we might also expect a cc/ua if another LUN on the target
687 * reported a UA with an ASC/ASCQ of 3F 0E -
688 * REPORTED LUNS DATA HAS CHANGED.
689 */
690 if (scmd->device->sdev_target->expecting_lun_change &&
691 sshdr.asc == 0x3f && sshdr.ascq == 0x0e)
692 return NEEDS_RETRY;
693 /*
694 * if the device is in the process of becoming ready, we
695 * should retry.
696 */
697 if ((sshdr.asc == 0x04) &&
698 (sshdr.ascq == 0x01 || sshdr.ascq == 0x0a))
699 return NEEDS_RETRY;
700 /*
701 * if the device is not started, we need to wake
702 * the error handler to start the motor
703 */
704 if (scmd->device->allow_restart &&
705 (sshdr.asc == 0x04) && (sshdr.ascq == 0x02))
706 return FAILED;
707 /*
708 * Pass the UA upwards for a determination in the completion
709 * functions.
710 */
711 return SUCCESS;
712
713 /* these are not supported */
714 case DATA_PROTECT:
715 if (sshdr.asc == 0x27 && sshdr.ascq == 0x07) {
716 /* Thin provisioning hard threshold reached */
717 set_scsi_ml_byte(scmd, SCSIML_STAT_NOSPC);
718 return SUCCESS;
719 }
720 fallthrough;
721 case COPY_ABORTED:
722 case VOLUME_OVERFLOW:
723 case MISCOMPARE:
724 case BLANK_CHECK:
725 set_scsi_ml_byte(scmd, SCSIML_STAT_TGT_FAILURE);
726 return SUCCESS;
727
728 case MEDIUM_ERROR:
729 if (sshdr.asc == 0x11 || /* UNRECOVERED READ ERR */
730 sshdr.asc == 0x13 || /* AMNF DATA FIELD */
731 sshdr.asc == 0x14) { /* RECORD NOT FOUND */
732 set_scsi_ml_byte(scmd, SCSIML_STAT_MED_ERROR);
733 return SUCCESS;
734 }
735 return NEEDS_RETRY;
736
737 case HARDWARE_ERROR:
738 if (scmd->device->retry_hwerror)
739 return ADD_TO_MLQUEUE;
740 else
741 set_scsi_ml_byte(scmd, SCSIML_STAT_TGT_FAILURE);
742 fallthrough;
743
744 case ILLEGAL_REQUEST:
745 if (sshdr.asc == 0x20 || /* Invalid command operation code */
746 sshdr.asc == 0x21 || /* Logical block address out of range */
747 sshdr.asc == 0x22 || /* Invalid function */
748 sshdr.asc == 0x24 || /* Invalid field in cdb */
749 sshdr.asc == 0x26 || /* Parameter value invalid */
750 sshdr.asc == 0x27) { /* Write protected */
751 set_scsi_ml_byte(scmd, SCSIML_STAT_TGT_FAILURE);
752 }
753 return SUCCESS;
754
755 case COMPLETED:
756 /*
757 * A command using command duration limits (CDL) with a
758 * descriptor set with policy 0xD may be completed with success
759 * and the sense data DATA CURRENTLY UNAVAILABLE, indicating
760 * that the command was in fact aborted because it exceeded its
761 * duration limit. Never retry these commands.
762 */
763 if (sshdr.asc == 0x55 && sshdr.ascq == 0x0a) {
764 set_scsi_ml_byte(scmd, SCSIML_STAT_DL_TIMEOUT);
765 req->cmd_flags |= REQ_FAILFAST_DEV;
766 req->rq_flags |= RQF_QUIET;
767 }
768 return SUCCESS;
769
770 default:
771 return SUCCESS;
772 }
773}
774EXPORT_SYMBOL_GPL(scsi_check_sense);
775
776static void scsi_handle_queue_ramp_up(struct scsi_device *sdev)
777{
778 const struct scsi_host_template *sht = sdev->host->hostt;
779 struct scsi_device *tmp_sdev;
780
781 if (!sdev->budget_map.map)
782 return;
783
784 if (!sht->track_queue_depth ||
785 sdev->queue_depth >= sdev->max_queue_depth)
786 return;
787
788 if (time_before(jiffies,
789 sdev->last_queue_ramp_up + sdev->queue_ramp_up_period))
790 return;
791
792 if (time_before(jiffies,
793 sdev->last_queue_full_time + sdev->queue_ramp_up_period))
794 return;
795
796 /*
797 * Walk all devices of a target and do
798 * ramp up on them.
799 */
800 shost_for_each_device(tmp_sdev, sdev->host) {
801 if (tmp_sdev->channel != sdev->channel ||
802 tmp_sdev->id != sdev->id ||
803 tmp_sdev->queue_depth == sdev->max_queue_depth)
804 continue;
805
806 scsi_change_queue_depth(tmp_sdev, tmp_sdev->queue_depth + 1);
807 sdev->last_queue_ramp_up = jiffies;
808 }
809}
810
811static void scsi_handle_queue_full(struct scsi_device *sdev)
812{
813 const struct scsi_host_template *sht = sdev->host->hostt;
814 struct scsi_device *tmp_sdev;
815
816 if (!sht->track_queue_depth)
817 return;
818
819 shost_for_each_device(tmp_sdev, sdev->host) {
820 if (tmp_sdev->channel != sdev->channel ||
821 tmp_sdev->id != sdev->id)
822 continue;
823 /*
824 * We do not know the number of commands that were at
825 * the device when we got the queue full so we start
826 * from the highest possible value and work our way down.
827 */
828 scsi_track_queue_full(tmp_sdev, tmp_sdev->queue_depth - 1);
829 }
830}
831
832/**
833 * scsi_eh_completed_normally - Disposition a eh cmd on return from LLD.
834 * @scmd: SCSI cmd to examine.
835 *
836 * Notes:
837 * This is *only* called when we are examining the status of commands
838 * queued during error recovery. the main difference here is that we
839 * don't allow for the possibility of retries here, and we are a lot
840 * more restrictive about what we consider acceptable.
841 */
842static enum scsi_disposition scsi_eh_completed_normally(struct scsi_cmnd *scmd)
843{
844 /*
845 * first check the host byte, to see if there is anything in there
846 * that would indicate what we need to do.
847 */
848 if (host_byte(scmd->result) == DID_RESET) {
849 /*
850 * rats. we are already in the error handler, so we now
851 * get to try and figure out what to do next. if the sense
852 * is valid, we have a pretty good idea of what to do.
853 * if not, we mark it as FAILED.
854 */
855 return scsi_check_sense(scmd);
856 }
857 if (host_byte(scmd->result) != DID_OK)
858 return FAILED;
859
860 /*
861 * now, check the status byte to see if this indicates
862 * anything special.
863 */
864 switch (get_status_byte(scmd)) {
865 case SAM_STAT_GOOD:
866 scsi_handle_queue_ramp_up(scmd->device);
867 if (scmd->sense_buffer && SCSI_SENSE_VALID(scmd))
868 /*
869 * If we have sense data, call scsi_check_sense() in
870 * order to set the correct SCSI ML byte (if any).
871 * No point in checking the return value, since the
872 * command has already completed successfully.
873 */
874 scsi_check_sense(scmd);
875 fallthrough;
876 case SAM_STAT_COMMAND_TERMINATED:
877 return SUCCESS;
878 case SAM_STAT_CHECK_CONDITION:
879 return scsi_check_sense(scmd);
880 case SAM_STAT_CONDITION_MET:
881 case SAM_STAT_INTERMEDIATE:
882 case SAM_STAT_INTERMEDIATE_CONDITION_MET:
883 /*
884 * who knows? FIXME(eric)
885 */
886 return SUCCESS;
887 case SAM_STAT_RESERVATION_CONFLICT:
888 if (scmd->cmnd[0] == TEST_UNIT_READY)
889 /* it is a success, we probed the device and
890 * found it */
891 return SUCCESS;
892 /* otherwise, we failed to send the command */
893 return FAILED;
894 case SAM_STAT_TASK_SET_FULL:
895 scsi_handle_queue_full(scmd->device);
896 fallthrough;
897 case SAM_STAT_BUSY:
898 return NEEDS_RETRY;
899 default:
900 return FAILED;
901 }
902 return FAILED;
903}
904
905/**
906 * scsi_eh_done - Completion function for error handling.
907 * @scmd: Cmd that is done.
908 */
909void scsi_eh_done(struct scsi_cmnd *scmd)
910{
911 struct completion *eh_action;
912
913 SCSI_LOG_ERROR_RECOVERY(3, scmd_printk(KERN_INFO, scmd,
914 "%s result: %x\n", __func__, scmd->result));
915
916 eh_action = scmd->device->host->eh_action;
917 if (eh_action)
918 complete(eh_action);
919}
920
921/**
922 * scsi_try_host_reset - ask host adapter to reset itself
923 * @scmd: SCSI cmd to send host reset.
924 */
925static enum scsi_disposition scsi_try_host_reset(struct scsi_cmnd *scmd)
926{
927 unsigned long flags;
928 enum scsi_disposition rtn;
929 struct Scsi_Host *host = scmd->device->host;
930 const struct scsi_host_template *hostt = host->hostt;
931
932 SCSI_LOG_ERROR_RECOVERY(3,
933 shost_printk(KERN_INFO, host, "Snd Host RST\n"));
934
935 if (!hostt->eh_host_reset_handler)
936 return FAILED;
937
938 rtn = hostt->eh_host_reset_handler(scmd);
939
940 if (rtn == SUCCESS) {
941 if (!hostt->skip_settle_delay)
942 ssleep(HOST_RESET_SETTLE_TIME);
943 spin_lock_irqsave(host->host_lock, flags);
944 scsi_report_bus_reset(host, scmd_channel(scmd));
945 spin_unlock_irqrestore(host->host_lock, flags);
946 }
947
948 return rtn;
949}
950
951/**
952 * scsi_try_bus_reset - ask host to perform a bus reset
953 * @scmd: SCSI cmd to send bus reset.
954 */
955static enum scsi_disposition scsi_try_bus_reset(struct scsi_cmnd *scmd)
956{
957 unsigned long flags;
958 enum scsi_disposition rtn;
959 struct Scsi_Host *host = scmd->device->host;
960 const struct scsi_host_template *hostt = host->hostt;
961
962 SCSI_LOG_ERROR_RECOVERY(3, scmd_printk(KERN_INFO, scmd,
963 "%s: Snd Bus RST\n", __func__));
964
965 if (!hostt->eh_bus_reset_handler)
966 return FAILED;
967
968 rtn = hostt->eh_bus_reset_handler(scmd);
969
970 if (rtn == SUCCESS) {
971 if (!hostt->skip_settle_delay)
972 ssleep(BUS_RESET_SETTLE_TIME);
973 spin_lock_irqsave(host->host_lock, flags);
974 scsi_report_bus_reset(host, scmd_channel(scmd));
975 spin_unlock_irqrestore(host->host_lock, flags);
976 }
977
978 return rtn;
979}
980
981static void __scsi_report_device_reset(struct scsi_device *sdev, void *data)
982{
983 sdev->was_reset = 1;
984 sdev->expecting_cc_ua = 1;
985}
986
987/**
988 * scsi_try_target_reset - Ask host to perform a target reset
989 * @scmd: SCSI cmd used to send a target reset
990 *
991 * Notes:
992 * There is no timeout for this operation. if this operation is
993 * unreliable for a given host, then the host itself needs to put a
994 * timer on it, and set the host back to a consistent state prior to
995 * returning.
996 */
997static enum scsi_disposition scsi_try_target_reset(struct scsi_cmnd *scmd)
998{
999 unsigned long flags;
1000 enum scsi_disposition rtn;
1001 struct Scsi_Host *host = scmd->device->host;
1002 const struct scsi_host_template *hostt = host->hostt;
1003
1004 if (!hostt->eh_target_reset_handler)
1005 return FAILED;
1006
1007 rtn = hostt->eh_target_reset_handler(scmd);
1008 if (rtn == SUCCESS) {
1009 spin_lock_irqsave(host->host_lock, flags);
1010 __starget_for_each_device(scsi_target(scmd->device), NULL,
1011 __scsi_report_device_reset);
1012 spin_unlock_irqrestore(host->host_lock, flags);
1013 }
1014
1015 return rtn;
1016}
1017
1018/**
1019 * scsi_try_bus_device_reset - Ask host to perform a BDR on a dev
1020 * @scmd: SCSI cmd used to send BDR
1021 *
1022 * Notes:
1023 * There is no timeout for this operation. if this operation is
1024 * unreliable for a given host, then the host itself needs to put a
1025 * timer on it, and set the host back to a consistent state prior to
1026 * returning.
1027 */
1028static enum scsi_disposition scsi_try_bus_device_reset(struct scsi_cmnd *scmd)
1029{
1030 enum scsi_disposition rtn;
1031 const struct scsi_host_template *hostt = scmd->device->host->hostt;
1032
1033 if (!hostt->eh_device_reset_handler)
1034 return FAILED;
1035
1036 rtn = hostt->eh_device_reset_handler(scmd);
1037 if (rtn == SUCCESS)
1038 __scsi_report_device_reset(scmd->device, NULL);
1039 return rtn;
1040}
1041
1042/**
1043 * scsi_try_to_abort_cmd - Ask host to abort a SCSI command
1044 * @hostt: SCSI driver host template
1045 * @scmd: SCSI cmd used to send a target reset
1046 *
1047 * Return value:
1048 * SUCCESS, FAILED, or FAST_IO_FAIL
1049 *
1050 * Notes:
1051 * SUCCESS does not necessarily indicate that the command
1052 * has been aborted; it only indicates that the LLDDs
1053 * has cleared all references to that command.
1054 * LLDDs should return FAILED only if an abort was required
1055 * but could not be executed. LLDDs should return FAST_IO_FAIL
1056 * if the device is temporarily unavailable (eg due to a
1057 * link down on FibreChannel)
1058 */
1059static enum scsi_disposition
1060scsi_try_to_abort_cmd(const struct scsi_host_template *hostt, struct scsi_cmnd *scmd)
1061{
1062 if (!hostt->eh_abort_handler)
1063 return FAILED;
1064
1065 return hostt->eh_abort_handler(scmd);
1066}
1067
1068static void scsi_abort_eh_cmnd(struct scsi_cmnd *scmd)
1069{
1070 if (scsi_try_to_abort_cmd(scmd->device->host->hostt, scmd) != SUCCESS)
1071 if (scsi_try_bus_device_reset(scmd) != SUCCESS)
1072 if (scsi_try_target_reset(scmd) != SUCCESS)
1073 if (scsi_try_bus_reset(scmd) != SUCCESS)
1074 scsi_try_host_reset(scmd);
1075}
1076
1077/**
1078 * scsi_eh_prep_cmnd - Save a scsi command info as part of error recovery
1079 * @scmd: SCSI command structure to hijack
1080 * @ses: structure to save restore information
1081 * @cmnd: CDB to send. Can be NULL if no new cmnd is needed
1082 * @cmnd_size: size in bytes of @cmnd (must be <= MAX_COMMAND_SIZE)
1083 * @sense_bytes: size of sense data to copy. or 0 (if != 0 @cmnd is ignored)
1084 *
1085 * This function is used to save a scsi command information before re-execution
1086 * as part of the error recovery process. If @sense_bytes is 0 the command
1087 * sent must be one that does not transfer any data. If @sense_bytes != 0
1088 * @cmnd is ignored and this functions sets up a REQUEST_SENSE command
1089 * and cmnd buffers to read @sense_bytes into @scmd->sense_buffer.
1090 */
1091void scsi_eh_prep_cmnd(struct scsi_cmnd *scmd, struct scsi_eh_save *ses,
1092 unsigned char *cmnd, int cmnd_size, unsigned sense_bytes)
1093{
1094 struct scsi_device *sdev = scmd->device;
1095#ifdef CONFIG_BLK_INLINE_ENCRYPTION
1096 struct request *rq = scsi_cmd_to_rq(scmd);
1097#endif
1098
1099 /*
1100 * We need saved copies of a number of fields - this is because
1101 * error handling may need to overwrite these with different values
1102 * to run different commands, and once error handling is complete,
1103 * we will need to restore these values prior to running the actual
1104 * command.
1105 */
1106 ses->cmd_len = scmd->cmd_len;
1107 ses->data_direction = scmd->sc_data_direction;
1108 ses->sdb = scmd->sdb;
1109 ses->result = scmd->result;
1110 ses->resid_len = scmd->resid_len;
1111 ses->underflow = scmd->underflow;
1112 ses->prot_op = scmd->prot_op;
1113 ses->eh_eflags = scmd->eh_eflags;
1114
1115 scmd->prot_op = SCSI_PROT_NORMAL;
1116 scmd->eh_eflags = 0;
1117 memcpy(ses->cmnd, scmd->cmnd, sizeof(ses->cmnd));
1118 memset(scmd->cmnd, 0, sizeof(scmd->cmnd));
1119 memset(&scmd->sdb, 0, sizeof(scmd->sdb));
1120 scmd->result = 0;
1121 scmd->resid_len = 0;
1122
1123 if (sense_bytes) {
1124 scmd->sdb.length = min_t(unsigned, SCSI_SENSE_BUFFERSIZE,
1125 sense_bytes);
1126 sg_init_one(&ses->sense_sgl, scmd->sense_buffer,
1127 scmd->sdb.length);
1128 scmd->sdb.table.sgl = &ses->sense_sgl;
1129 scmd->sc_data_direction = DMA_FROM_DEVICE;
1130 scmd->sdb.table.nents = scmd->sdb.table.orig_nents = 1;
1131 scmd->cmnd[0] = REQUEST_SENSE;
1132 scmd->cmnd[4] = scmd->sdb.length;
1133 scmd->cmd_len = COMMAND_SIZE(scmd->cmnd[0]);
1134 } else {
1135 scmd->sc_data_direction = DMA_NONE;
1136 if (cmnd) {
1137 BUG_ON(cmnd_size > sizeof(scmd->cmnd));
1138 memcpy(scmd->cmnd, cmnd, cmnd_size);
1139 scmd->cmd_len = COMMAND_SIZE(scmd->cmnd[0]);
1140 }
1141 }
1142
1143 scmd->underflow = 0;
1144
1145 if (sdev->scsi_level <= SCSI_2 && sdev->scsi_level != SCSI_UNKNOWN)
1146 scmd->cmnd[1] = (scmd->cmnd[1] & 0x1f) |
1147 (sdev->lun << 5 & 0xe0);
1148
1149 /*
1150 * Encryption must be disabled for the commands submitted by the error handler.
1151 * Hence, clear the encryption context information.
1152 */
1153#ifdef CONFIG_BLK_INLINE_ENCRYPTION
1154 ses->rq_crypt_keyslot = rq->crypt_keyslot;
1155 ses->rq_crypt_ctx = rq->crypt_ctx;
1156
1157 rq->crypt_keyslot = NULL;
1158 rq->crypt_ctx = NULL;
1159#endif
1160
1161 /*
1162 * Zero the sense buffer. The scsi spec mandates that any
1163 * untransferred sense data should be interpreted as being zero.
1164 */
1165 memset(scmd->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE);
1166}
1167EXPORT_SYMBOL(scsi_eh_prep_cmnd);
1168
1169/**
1170 * scsi_eh_restore_cmnd - Restore a scsi command info as part of error recovery
1171 * @scmd: SCSI command structure to restore
1172 * @ses: saved information from a coresponding call to scsi_eh_prep_cmnd
1173 *
1174 * Undo any damage done by above scsi_eh_prep_cmnd().
1175 */
1176void scsi_eh_restore_cmnd(struct scsi_cmnd* scmd, struct scsi_eh_save *ses)
1177{
1178#ifdef CONFIG_BLK_INLINE_ENCRYPTION
1179 struct request *rq = scsi_cmd_to_rq(scmd);
1180#endif
1181
1182 /*
1183 * Restore original data
1184 */
1185 scmd->cmd_len = ses->cmd_len;
1186 memcpy(scmd->cmnd, ses->cmnd, sizeof(ses->cmnd));
1187 scmd->sc_data_direction = ses->data_direction;
1188 scmd->sdb = ses->sdb;
1189 scmd->result = ses->result;
1190 scmd->resid_len = ses->resid_len;
1191 scmd->underflow = ses->underflow;
1192 scmd->prot_op = ses->prot_op;
1193 scmd->eh_eflags = ses->eh_eflags;
1194
1195#ifdef CONFIG_BLK_INLINE_ENCRYPTION
1196 rq->crypt_keyslot = ses->rq_crypt_keyslot;
1197 rq->crypt_ctx = ses->rq_crypt_ctx;
1198#endif
1199}
1200EXPORT_SYMBOL(scsi_eh_restore_cmnd);
1201
1202/**
1203 * scsi_send_eh_cmnd - submit a scsi command as part of error recovery
1204 * @scmd: SCSI command structure to hijack
1205 * @cmnd: CDB to send
1206 * @cmnd_size: size in bytes of @cmnd
1207 * @timeout: timeout for this request
1208 * @sense_bytes: size of sense data to copy or 0
1209 *
1210 * This function is used to send a scsi command down to a target device
1211 * as part of the error recovery process. See also scsi_eh_prep_cmnd() above.
1212 *
1213 * Return value:
1214 * SUCCESS or FAILED or NEEDS_RETRY
1215 */
1216static enum scsi_disposition scsi_send_eh_cmnd(struct scsi_cmnd *scmd,
1217 unsigned char *cmnd, int cmnd_size, int timeout, unsigned sense_bytes)
1218{
1219 struct scsi_device *sdev = scmd->device;
1220 struct Scsi_Host *shost = sdev->host;
1221 DECLARE_COMPLETION_ONSTACK(done);
1222 unsigned long timeleft = timeout, delay;
1223 struct scsi_eh_save ses;
1224 const unsigned long stall_for = msecs_to_jiffies(100);
1225 int rtn;
1226
1227retry:
1228 scsi_eh_prep_cmnd(scmd, &ses, cmnd, cmnd_size, sense_bytes);
1229 shost->eh_action = &done;
1230
1231 scsi_log_send(scmd);
1232 scmd->submitter = SUBMITTED_BY_SCSI_ERROR_HANDLER;
1233 scmd->flags |= SCMD_LAST;
1234
1235 /*
1236 * Lock sdev->state_mutex to avoid that scsi_device_quiesce() can
1237 * change the SCSI device state after we have examined it and before
1238 * .queuecommand() is called.
1239 */
1240 mutex_lock(&sdev->state_mutex);
1241 while (sdev->sdev_state == SDEV_BLOCK && timeleft > 0) {
1242 mutex_unlock(&sdev->state_mutex);
1243 SCSI_LOG_ERROR_RECOVERY(5, sdev_printk(KERN_DEBUG, sdev,
1244 "%s: state %d <> %d\n", __func__, sdev->sdev_state,
1245 SDEV_BLOCK));
1246 delay = min(timeleft, stall_for);
1247 timeleft -= delay;
1248 msleep(jiffies_to_msecs(delay));
1249 mutex_lock(&sdev->state_mutex);
1250 }
1251 if (sdev->sdev_state != SDEV_BLOCK)
1252 rtn = shost->hostt->queuecommand(shost, scmd);
1253 else
1254 rtn = FAILED;
1255 mutex_unlock(&sdev->state_mutex);
1256
1257 if (rtn) {
1258 if (timeleft > stall_for) {
1259 scsi_eh_restore_cmnd(scmd, &ses);
1260
1261 timeleft -= stall_for;
1262 msleep(jiffies_to_msecs(stall_for));
1263 goto retry;
1264 }
1265 /* signal not to enter either branch of the if () below */
1266 timeleft = 0;
1267 rtn = FAILED;
1268 } else {
1269 timeleft = wait_for_completion_timeout(&done, timeout);
1270 rtn = SUCCESS;
1271 }
1272
1273 shost->eh_action = NULL;
1274
1275 scsi_log_completion(scmd, rtn);
1276
1277 SCSI_LOG_ERROR_RECOVERY(3, scmd_printk(KERN_INFO, scmd,
1278 "%s timeleft: %ld\n",
1279 __func__, timeleft));
1280
1281 /*
1282 * If there is time left scsi_eh_done got called, and we will examine
1283 * the actual status codes to see whether the command actually did
1284 * complete normally, else if we have a zero return and no time left,
1285 * the command must still be pending, so abort it and return FAILED.
1286 * If we never actually managed to issue the command, because
1287 * ->queuecommand() kept returning non zero, use the rtn = FAILED
1288 * value above (so don't execute either branch of the if)
1289 */
1290 if (timeleft) {
1291 rtn = scsi_eh_completed_normally(scmd);
1292 SCSI_LOG_ERROR_RECOVERY(3, scmd_printk(KERN_INFO, scmd,
1293 "%s: scsi_eh_completed_normally %x\n", __func__, rtn));
1294
1295 switch (rtn) {
1296 case SUCCESS:
1297 case NEEDS_RETRY:
1298 case FAILED:
1299 break;
1300 case ADD_TO_MLQUEUE:
1301 rtn = NEEDS_RETRY;
1302 break;
1303 default:
1304 rtn = FAILED;
1305 break;
1306 }
1307 } else if (rtn != FAILED) {
1308 scsi_abort_eh_cmnd(scmd);
1309 rtn = FAILED;
1310 }
1311
1312 scsi_eh_restore_cmnd(scmd, &ses);
1313
1314 return rtn;
1315}
1316
1317/**
1318 * scsi_request_sense - Request sense data from a particular target.
1319 * @scmd: SCSI cmd for request sense.
1320 *
1321 * Notes:
1322 * Some hosts automatically obtain this information, others require
1323 * that we obtain it on our own. This function will *not* return until
1324 * the command either times out, or it completes.
1325 */
1326static enum scsi_disposition scsi_request_sense(struct scsi_cmnd *scmd)
1327{
1328 return scsi_send_eh_cmnd(scmd, NULL, 0, scmd->device->eh_timeout, ~0);
1329}
1330
1331static enum scsi_disposition
1332scsi_eh_action(struct scsi_cmnd *scmd, enum scsi_disposition rtn)
1333{
1334 if (!blk_rq_is_passthrough(scsi_cmd_to_rq(scmd))) {
1335 struct scsi_driver *sdrv = scsi_cmd_to_driver(scmd);
1336 if (sdrv->eh_action)
1337 rtn = sdrv->eh_action(scmd, rtn);
1338 }
1339 return rtn;
1340}
1341
1342/**
1343 * scsi_eh_finish_cmd - Handle a cmd that eh is finished with.
1344 * @scmd: Original SCSI cmd that eh has finished.
1345 * @done_q: Queue for processed commands.
1346 *
1347 * Notes:
1348 * We don't want to use the normal command completion while we are are
1349 * still handling errors - it may cause other commands to be queued,
1350 * and that would disturb what we are doing. Thus we really want to
1351 * keep a list of pending commands for final completion, and once we
1352 * are ready to leave error handling we handle completion for real.
1353 */
1354void scsi_eh_finish_cmd(struct scsi_cmnd *scmd, struct list_head *done_q)
1355{
1356 list_move_tail(&scmd->eh_entry, done_q);
1357}
1358EXPORT_SYMBOL(scsi_eh_finish_cmd);
1359
1360/**
1361 * scsi_eh_get_sense - Get device sense data.
1362 * @work_q: Queue of commands to process.
1363 * @done_q: Queue of processed commands.
1364 *
1365 * Description:
1366 * See if we need to request sense information. if so, then get it
1367 * now, so we have a better idea of what to do.
1368 *
1369 * Notes:
1370 * This has the unfortunate side effect that if a shost adapter does
1371 * not automatically request sense information, we end up shutting
1372 * it down before we request it.
1373 *
1374 * All drivers should request sense information internally these days,
1375 * so for now all I have to say is tough noogies if you end up in here.
1376 *
1377 * XXX: Long term this code should go away, but that needs an audit of
1378 * all LLDDs first.
1379 */
1380int scsi_eh_get_sense(struct list_head *work_q,
1381 struct list_head *done_q)
1382{
1383 struct scsi_cmnd *scmd, *next;
1384 struct Scsi_Host *shost;
1385 enum scsi_disposition rtn;
1386
1387 /*
1388 * If SCSI_EH_ABORT_SCHEDULED has been set, it is timeout IO,
1389 * should not get sense.
1390 */
1391 list_for_each_entry_safe(scmd, next, work_q, eh_entry) {
1392 if ((scmd->eh_eflags & SCSI_EH_ABORT_SCHEDULED) ||
1393 SCSI_SENSE_VALID(scmd))
1394 continue;
1395
1396 shost = scmd->device->host;
1397 if (scsi_host_eh_past_deadline(shost)) {
1398 SCSI_LOG_ERROR_RECOVERY(3,
1399 scmd_printk(KERN_INFO, scmd,
1400 "%s: skip request sense, past eh deadline\n",
1401 current->comm));
1402 break;
1403 }
1404 if (!scsi_status_is_check_condition(scmd->result))
1405 /*
1406 * don't request sense if there's no check condition
1407 * status because the error we're processing isn't one
1408 * that has a sense code (and some devices get
1409 * confused by sense requests out of the blue)
1410 */
1411 continue;
1412
1413 SCSI_LOG_ERROR_RECOVERY(2, scmd_printk(KERN_INFO, scmd,
1414 "%s: requesting sense\n",
1415 current->comm));
1416 rtn = scsi_request_sense(scmd);
1417 if (rtn != SUCCESS)
1418 continue;
1419
1420 SCSI_LOG_ERROR_RECOVERY(3, scmd_printk(KERN_INFO, scmd,
1421 "sense requested, result %x\n", scmd->result));
1422 SCSI_LOG_ERROR_RECOVERY(3, scsi_print_sense(scmd));
1423
1424 rtn = scsi_decide_disposition(scmd);
1425
1426 /*
1427 * if the result was normal, then just pass it along to the
1428 * upper level.
1429 */
1430 if (rtn == SUCCESS)
1431 /*
1432 * We don't want this command reissued, just finished
1433 * with the sense data, so set retries to the max
1434 * allowed to ensure it won't get reissued. If the user
1435 * has requested infinite retries, we also want to
1436 * finish this command, so force completion by setting
1437 * retries and allowed to the same value.
1438 */
1439 if (scmd->allowed == SCSI_CMD_RETRIES_NO_LIMIT)
1440 scmd->retries = scmd->allowed = 1;
1441 else
1442 scmd->retries = scmd->allowed;
1443 else if (rtn != NEEDS_RETRY)
1444 continue;
1445
1446 scsi_eh_finish_cmd(scmd, done_q);
1447 }
1448
1449 return list_empty(work_q);
1450}
1451EXPORT_SYMBOL_GPL(scsi_eh_get_sense);
1452
1453/**
1454 * scsi_eh_tur - Send TUR to device.
1455 * @scmd: &scsi_cmnd to send TUR
1456 *
1457 * Return value:
1458 * 0 - Device is ready. 1 - Device NOT ready.
1459 */
1460static int scsi_eh_tur(struct scsi_cmnd *scmd)
1461{
1462 static unsigned char tur_command[6] = {TEST_UNIT_READY, 0, 0, 0, 0, 0};
1463 int retry_cnt = 1;
1464 enum scsi_disposition rtn;
1465
1466retry_tur:
1467 rtn = scsi_send_eh_cmnd(scmd, tur_command, 6,
1468 scmd->device->eh_timeout, 0);
1469
1470 SCSI_LOG_ERROR_RECOVERY(3, scmd_printk(KERN_INFO, scmd,
1471 "%s return: %x\n", __func__, rtn));
1472
1473 switch (rtn) {
1474 case NEEDS_RETRY:
1475 if (retry_cnt--)
1476 goto retry_tur;
1477 fallthrough;
1478 case SUCCESS:
1479 return 0;
1480 default:
1481 return 1;
1482 }
1483}
1484
1485/**
1486 * scsi_eh_test_devices - check if devices are responding from error recovery.
1487 * @cmd_list: scsi commands in error recovery.
1488 * @work_q: queue for commands which still need more error recovery
1489 * @done_q: queue for commands which are finished
1490 * @try_stu: boolean on if a STU command should be tried in addition to TUR.
1491 *
1492 * Decription:
1493 * Tests if devices are in a working state. Commands to devices now in
1494 * a working state are sent to the done_q while commands to devices which
1495 * are still failing to respond are returned to the work_q for more
1496 * processing.
1497 **/
1498static int scsi_eh_test_devices(struct list_head *cmd_list,
1499 struct list_head *work_q,
1500 struct list_head *done_q, int try_stu)
1501{
1502 struct scsi_cmnd *scmd, *next;
1503 struct scsi_device *sdev;
1504 int finish_cmds;
1505
1506 while (!list_empty(cmd_list)) {
1507 scmd = list_entry(cmd_list->next, struct scsi_cmnd, eh_entry);
1508 sdev = scmd->device;
1509
1510 if (!try_stu) {
1511 if (scsi_host_eh_past_deadline(sdev->host)) {
1512 /* Push items back onto work_q */
1513 list_splice_init(cmd_list, work_q);
1514 SCSI_LOG_ERROR_RECOVERY(3,
1515 sdev_printk(KERN_INFO, sdev,
1516 "%s: skip test device, past eh deadline",
1517 current->comm));
1518 break;
1519 }
1520 }
1521
1522 finish_cmds = !scsi_device_online(scmd->device) ||
1523 (try_stu && !scsi_eh_try_stu(scmd) &&
1524 !scsi_eh_tur(scmd)) ||
1525 !scsi_eh_tur(scmd);
1526
1527 list_for_each_entry_safe(scmd, next, cmd_list, eh_entry)
1528 if (scmd->device == sdev) {
1529 if (finish_cmds &&
1530 (try_stu ||
1531 scsi_eh_action(scmd, SUCCESS) == SUCCESS))
1532 scsi_eh_finish_cmd(scmd, done_q);
1533 else
1534 list_move_tail(&scmd->eh_entry, work_q);
1535 }
1536 }
1537 return list_empty(work_q);
1538}
1539
1540/**
1541 * scsi_eh_try_stu - Send START_UNIT to device.
1542 * @scmd: &scsi_cmnd to send START_UNIT
1543 *
1544 * Return value:
1545 * 0 - Device is ready. 1 - Device NOT ready.
1546 */
1547static int scsi_eh_try_stu(struct scsi_cmnd *scmd)
1548{
1549 static unsigned char stu_command[6] = {START_STOP, 0, 0, 0, 1, 0};
1550
1551 if (scmd->device->allow_restart) {
1552 int i;
1553 enum scsi_disposition rtn = NEEDS_RETRY;
1554
1555 for (i = 0; rtn == NEEDS_RETRY && i < 2; i++)
1556 rtn = scsi_send_eh_cmnd(scmd, stu_command, 6,
1557 scmd->device->eh_timeout, 0);
1558
1559 if (rtn == SUCCESS)
1560 return 0;
1561 }
1562
1563 return 1;
1564}
1565
1566 /**
1567 * scsi_eh_stu - send START_UNIT if needed
1568 * @shost: &scsi host being recovered.
1569 * @work_q: &list_head for pending commands.
1570 * @done_q: &list_head for processed commands.
1571 *
1572 * Notes:
1573 * If commands are failing due to not ready, initializing command required,
1574 * try revalidating the device, which will end up sending a start unit.
1575 */
1576static int scsi_eh_stu(struct Scsi_Host *shost,
1577 struct list_head *work_q,
1578 struct list_head *done_q)
1579{
1580 struct scsi_cmnd *scmd, *stu_scmd, *next;
1581 struct scsi_device *sdev;
1582
1583 shost_for_each_device(sdev, shost) {
1584 if (scsi_host_eh_past_deadline(shost)) {
1585 SCSI_LOG_ERROR_RECOVERY(3,
1586 sdev_printk(KERN_INFO, sdev,
1587 "%s: skip START_UNIT, past eh deadline\n",
1588 current->comm));
1589 scsi_device_put(sdev);
1590 break;
1591 }
1592 stu_scmd = NULL;
1593 list_for_each_entry(scmd, work_q, eh_entry)
1594 if (scmd->device == sdev && SCSI_SENSE_VALID(scmd) &&
1595 scsi_check_sense(scmd) == FAILED ) {
1596 stu_scmd = scmd;
1597 break;
1598 }
1599
1600 if (!stu_scmd)
1601 continue;
1602
1603 SCSI_LOG_ERROR_RECOVERY(3,
1604 sdev_printk(KERN_INFO, sdev,
1605 "%s: Sending START_UNIT\n",
1606 current->comm));
1607
1608 if (!scsi_eh_try_stu(stu_scmd)) {
1609 if (!scsi_device_online(sdev) ||
1610 !scsi_eh_tur(stu_scmd)) {
1611 list_for_each_entry_safe(scmd, next,
1612 work_q, eh_entry) {
1613 if (scmd->device == sdev &&
1614 scsi_eh_action(scmd, SUCCESS) == SUCCESS)
1615 scsi_eh_finish_cmd(scmd, done_q);
1616 }
1617 }
1618 } else {
1619 SCSI_LOG_ERROR_RECOVERY(3,
1620 sdev_printk(KERN_INFO, sdev,
1621 "%s: START_UNIT failed\n",
1622 current->comm));
1623 }
1624 }
1625
1626 return list_empty(work_q);
1627}
1628
1629
1630/**
1631 * scsi_eh_bus_device_reset - send bdr if needed
1632 * @shost: scsi host being recovered.
1633 * @work_q: &list_head for pending commands.
1634 * @done_q: &list_head for processed commands.
1635 *
1636 * Notes:
1637 * Try a bus device reset. Still, look to see whether we have multiple
1638 * devices that are jammed or not - if we have multiple devices, it
1639 * makes no sense to try bus_device_reset - we really would need to try
1640 * a bus_reset instead.
1641 */
1642static int scsi_eh_bus_device_reset(struct Scsi_Host *shost,
1643 struct list_head *work_q,
1644 struct list_head *done_q)
1645{
1646 struct scsi_cmnd *scmd, *bdr_scmd, *next;
1647 struct scsi_device *sdev;
1648 enum scsi_disposition rtn;
1649
1650 shost_for_each_device(sdev, shost) {
1651 if (scsi_host_eh_past_deadline(shost)) {
1652 SCSI_LOG_ERROR_RECOVERY(3,
1653 sdev_printk(KERN_INFO, sdev,
1654 "%s: skip BDR, past eh deadline\n",
1655 current->comm));
1656 scsi_device_put(sdev);
1657 break;
1658 }
1659 bdr_scmd = NULL;
1660 list_for_each_entry(scmd, work_q, eh_entry)
1661 if (scmd->device == sdev) {
1662 bdr_scmd = scmd;
1663 break;
1664 }
1665
1666 if (!bdr_scmd)
1667 continue;
1668
1669 SCSI_LOG_ERROR_RECOVERY(3,
1670 sdev_printk(KERN_INFO, sdev,
1671 "%s: Sending BDR\n", current->comm));
1672 rtn = scsi_try_bus_device_reset(bdr_scmd);
1673 if (rtn == SUCCESS || rtn == FAST_IO_FAIL) {
1674 if (!scsi_device_online(sdev) ||
1675 rtn == FAST_IO_FAIL ||
1676 !scsi_eh_tur(bdr_scmd)) {
1677 list_for_each_entry_safe(scmd, next,
1678 work_q, eh_entry) {
1679 if (scmd->device == sdev &&
1680 scsi_eh_action(scmd, rtn) != FAILED)
1681 scsi_eh_finish_cmd(scmd,
1682 done_q);
1683 }
1684 }
1685 } else {
1686 SCSI_LOG_ERROR_RECOVERY(3,
1687 sdev_printk(KERN_INFO, sdev,
1688 "%s: BDR failed\n", current->comm));
1689 }
1690 }
1691
1692 return list_empty(work_q);
1693}
1694
1695/**
1696 * scsi_eh_target_reset - send target reset if needed
1697 * @shost: scsi host being recovered.
1698 * @work_q: &list_head for pending commands.
1699 * @done_q: &list_head for processed commands.
1700 *
1701 * Notes:
1702 * Try a target reset.
1703 */
1704static int scsi_eh_target_reset(struct Scsi_Host *shost,
1705 struct list_head *work_q,
1706 struct list_head *done_q)
1707{
1708 LIST_HEAD(tmp_list);
1709 LIST_HEAD(check_list);
1710
1711 list_splice_init(work_q, &tmp_list);
1712
1713 while (!list_empty(&tmp_list)) {
1714 struct scsi_cmnd *next, *scmd;
1715 enum scsi_disposition rtn;
1716 unsigned int id;
1717
1718 if (scsi_host_eh_past_deadline(shost)) {
1719 /* push back on work queue for further processing */
1720 list_splice_init(&check_list, work_q);
1721 list_splice_init(&tmp_list, work_q);
1722 SCSI_LOG_ERROR_RECOVERY(3,
1723 shost_printk(KERN_INFO, shost,
1724 "%s: Skip target reset, past eh deadline\n",
1725 current->comm));
1726 return list_empty(work_q);
1727 }
1728
1729 scmd = list_entry(tmp_list.next, struct scsi_cmnd, eh_entry);
1730 id = scmd_id(scmd);
1731
1732 SCSI_LOG_ERROR_RECOVERY(3,
1733 shost_printk(KERN_INFO, shost,
1734 "%s: Sending target reset to target %d\n",
1735 current->comm, id));
1736 rtn = scsi_try_target_reset(scmd);
1737 if (rtn != SUCCESS && rtn != FAST_IO_FAIL)
1738 SCSI_LOG_ERROR_RECOVERY(3,
1739 shost_printk(KERN_INFO, shost,
1740 "%s: Target reset failed"
1741 " target: %d\n",
1742 current->comm, id));
1743 list_for_each_entry_safe(scmd, next, &tmp_list, eh_entry) {
1744 if (scmd_id(scmd) != id)
1745 continue;
1746
1747 if (rtn == SUCCESS)
1748 list_move_tail(&scmd->eh_entry, &check_list);
1749 else if (rtn == FAST_IO_FAIL)
1750 scsi_eh_finish_cmd(scmd, done_q);
1751 else
1752 /* push back on work queue for further processing */
1753 list_move(&scmd->eh_entry, work_q);
1754 }
1755 }
1756
1757 return scsi_eh_test_devices(&check_list, work_q, done_q, 0);
1758}
1759
1760/**
1761 * scsi_eh_bus_reset - send a bus reset
1762 * @shost: &scsi host being recovered.
1763 * @work_q: &list_head for pending commands.
1764 * @done_q: &list_head for processed commands.
1765 */
1766static int scsi_eh_bus_reset(struct Scsi_Host *shost,
1767 struct list_head *work_q,
1768 struct list_head *done_q)
1769{
1770 struct scsi_cmnd *scmd, *chan_scmd, *next;
1771 LIST_HEAD(check_list);
1772 unsigned int channel;
1773 enum scsi_disposition rtn;
1774
1775 /*
1776 * we really want to loop over the various channels, and do this on
1777 * a channel by channel basis. we should also check to see if any
1778 * of the failed commands are on soft_reset devices, and if so, skip
1779 * the reset.
1780 */
1781
1782 for (channel = 0; channel <= shost->max_channel; channel++) {
1783 if (scsi_host_eh_past_deadline(shost)) {
1784 list_splice_init(&check_list, work_q);
1785 SCSI_LOG_ERROR_RECOVERY(3,
1786 shost_printk(KERN_INFO, shost,
1787 "%s: skip BRST, past eh deadline\n",
1788 current->comm));
1789 return list_empty(work_q);
1790 }
1791
1792 chan_scmd = NULL;
1793 list_for_each_entry(scmd, work_q, eh_entry) {
1794 if (channel == scmd_channel(scmd)) {
1795 chan_scmd = scmd;
1796 break;
1797 /*
1798 * FIXME add back in some support for
1799 * soft_reset devices.
1800 */
1801 }
1802 }
1803
1804 if (!chan_scmd)
1805 continue;
1806 SCSI_LOG_ERROR_RECOVERY(3,
1807 shost_printk(KERN_INFO, shost,
1808 "%s: Sending BRST chan: %d\n",
1809 current->comm, channel));
1810 rtn = scsi_try_bus_reset(chan_scmd);
1811 if (rtn == SUCCESS || rtn == FAST_IO_FAIL) {
1812 list_for_each_entry_safe(scmd, next, work_q, eh_entry) {
1813 if (channel == scmd_channel(scmd)) {
1814 if (rtn == FAST_IO_FAIL)
1815 scsi_eh_finish_cmd(scmd,
1816 done_q);
1817 else
1818 list_move_tail(&scmd->eh_entry,
1819 &check_list);
1820 }
1821 }
1822 } else {
1823 SCSI_LOG_ERROR_RECOVERY(3,
1824 shost_printk(KERN_INFO, shost,
1825 "%s: BRST failed chan: %d\n",
1826 current->comm, channel));
1827 }
1828 }
1829 return scsi_eh_test_devices(&check_list, work_q, done_q, 0);
1830}
1831
1832/**
1833 * scsi_eh_host_reset - send a host reset
1834 * @shost: host to be reset.
1835 * @work_q: &list_head for pending commands.
1836 * @done_q: &list_head for processed commands.
1837 */
1838static int scsi_eh_host_reset(struct Scsi_Host *shost,
1839 struct list_head *work_q,
1840 struct list_head *done_q)
1841{
1842 struct scsi_cmnd *scmd, *next;
1843 LIST_HEAD(check_list);
1844 enum scsi_disposition rtn;
1845
1846 if (!list_empty(work_q)) {
1847 scmd = list_entry(work_q->next,
1848 struct scsi_cmnd, eh_entry);
1849
1850 SCSI_LOG_ERROR_RECOVERY(3,
1851 shost_printk(KERN_INFO, shost,
1852 "%s: Sending HRST\n",
1853 current->comm));
1854
1855 rtn = scsi_try_host_reset(scmd);
1856 if (rtn == SUCCESS) {
1857 list_splice_init(work_q, &check_list);
1858 } else if (rtn == FAST_IO_FAIL) {
1859 list_for_each_entry_safe(scmd, next, work_q, eh_entry) {
1860 scsi_eh_finish_cmd(scmd, done_q);
1861 }
1862 } else {
1863 SCSI_LOG_ERROR_RECOVERY(3,
1864 shost_printk(KERN_INFO, shost,
1865 "%s: HRST failed\n",
1866 current->comm));
1867 }
1868 }
1869 return scsi_eh_test_devices(&check_list, work_q, done_q, 1);
1870}
1871
1872/**
1873 * scsi_eh_offline_sdevs - offline scsi devices that fail to recover
1874 * @work_q: &list_head for pending commands.
1875 * @done_q: &list_head for processed commands.
1876 */
1877static void scsi_eh_offline_sdevs(struct list_head *work_q,
1878 struct list_head *done_q)
1879{
1880 struct scsi_cmnd *scmd, *next;
1881 struct scsi_device *sdev;
1882
1883 list_for_each_entry_safe(scmd, next, work_q, eh_entry) {
1884 sdev_printk(KERN_INFO, scmd->device, "Device offlined - "
1885 "not ready after error recovery\n");
1886 sdev = scmd->device;
1887
1888 mutex_lock(&sdev->state_mutex);
1889 scsi_device_set_state(sdev, SDEV_OFFLINE);
1890 mutex_unlock(&sdev->state_mutex);
1891
1892 scsi_eh_finish_cmd(scmd, done_q);
1893 }
1894 return;
1895}
1896
1897/**
1898 * scsi_noretry_cmd - determine if command should be failed fast
1899 * @scmd: SCSI cmd to examine.
1900 */
1901bool scsi_noretry_cmd(struct scsi_cmnd *scmd)
1902{
1903 struct request *req = scsi_cmd_to_rq(scmd);
1904
1905 switch (host_byte(scmd->result)) {
1906 case DID_OK:
1907 break;
1908 case DID_TIME_OUT:
1909 goto check_type;
1910 case DID_BUS_BUSY:
1911 return !!(req->cmd_flags & REQ_FAILFAST_TRANSPORT);
1912 case DID_PARITY:
1913 return !!(req->cmd_flags & REQ_FAILFAST_DEV);
1914 case DID_ERROR:
1915 if (get_status_byte(scmd) == SAM_STAT_RESERVATION_CONFLICT)
1916 return false;
1917 fallthrough;
1918 case DID_SOFT_ERROR:
1919 return !!(req->cmd_flags & REQ_FAILFAST_DRIVER);
1920 }
1921
1922 /* Never retry commands aborted due to a duration limit timeout */
1923 if (scsi_ml_byte(scmd->result) == SCSIML_STAT_DL_TIMEOUT)
1924 return true;
1925
1926 if (!scsi_status_is_check_condition(scmd->result))
1927 return false;
1928
1929check_type:
1930 /*
1931 * assume caller has checked sense and determined
1932 * the check condition was retryable.
1933 */
1934 if (req->cmd_flags & REQ_FAILFAST_DEV || blk_rq_is_passthrough(req))
1935 return true;
1936
1937 return false;
1938}
1939
1940/**
1941 * scsi_decide_disposition - Disposition a cmd on return from LLD.
1942 * @scmd: SCSI cmd to examine.
1943 *
1944 * Notes:
1945 * This is *only* called when we are examining the status after sending
1946 * out the actual data command. any commands that are queued for error
1947 * recovery (e.g. test_unit_ready) do *not* come through here.
1948 *
1949 * When this routine returns failed, it means the error handler thread
1950 * is woken. In cases where the error code indicates an error that
1951 * doesn't require the error handler read (i.e. we don't need to
1952 * abort/reset), this function should return SUCCESS.
1953 */
1954enum scsi_disposition scsi_decide_disposition(struct scsi_cmnd *scmd)
1955{
1956 enum scsi_disposition rtn;
1957
1958 /*
1959 * if the device is offline, then we clearly just pass the result back
1960 * up to the top level.
1961 */
1962 if (!scsi_device_online(scmd->device)) {
1963 SCSI_LOG_ERROR_RECOVERY(5, scmd_printk(KERN_INFO, scmd,
1964 "%s: device offline - report as SUCCESS\n", __func__));
1965 return SUCCESS;
1966 }
1967
1968 /*
1969 * first check the host byte, to see if there is anything in there
1970 * that would indicate what we need to do.
1971 */
1972 switch (host_byte(scmd->result)) {
1973 case DID_PASSTHROUGH:
1974 /*
1975 * no matter what, pass this through to the upper layer.
1976 * nuke this special code so that it looks like we are saying
1977 * did_ok.
1978 */
1979 scmd->result &= 0xff00ffff;
1980 return SUCCESS;
1981 case DID_OK:
1982 /*
1983 * looks good. drop through, and check the next byte.
1984 */
1985 break;
1986 case DID_ABORT:
1987 if (scmd->eh_eflags & SCSI_EH_ABORT_SCHEDULED) {
1988 set_host_byte(scmd, DID_TIME_OUT);
1989 return SUCCESS;
1990 }
1991 fallthrough;
1992 case DID_NO_CONNECT:
1993 case DID_BAD_TARGET:
1994 /*
1995 * note - this means that we just report the status back
1996 * to the top level driver, not that we actually think
1997 * that it indicates SUCCESS.
1998 */
1999 return SUCCESS;
2000 case DID_SOFT_ERROR:
2001 /*
2002 * when the low level driver returns did_soft_error,
2003 * it is responsible for keeping an internal retry counter
2004 * in order to avoid endless loops (db)
2005 */
2006 goto maybe_retry;
2007 case DID_IMM_RETRY:
2008 return NEEDS_RETRY;
2009
2010 case DID_REQUEUE:
2011 return ADD_TO_MLQUEUE;
2012 case DID_TRANSPORT_DISRUPTED:
2013 /*
2014 * LLD/transport was disrupted during processing of the IO.
2015 * The transport class is now blocked/blocking,
2016 * and the transport will decide what to do with the IO
2017 * based on its timers and recovery capablilities if
2018 * there are enough retries.
2019 */
2020 goto maybe_retry;
2021 case DID_TRANSPORT_FAILFAST:
2022 /*
2023 * The transport decided to failfast the IO (most likely
2024 * the fast io fail tmo fired), so send IO directly upwards.
2025 */
2026 return SUCCESS;
2027 case DID_TRANSPORT_MARGINAL:
2028 /*
2029 * caller has decided not to do retries on
2030 * abort success, so send IO directly upwards
2031 */
2032 return SUCCESS;
2033 case DID_ERROR:
2034 if (get_status_byte(scmd) == SAM_STAT_RESERVATION_CONFLICT)
2035 /*
2036 * execute reservation conflict processing code
2037 * lower down
2038 */
2039 break;
2040 fallthrough;
2041 case DID_BUS_BUSY:
2042 case DID_PARITY:
2043 goto maybe_retry;
2044 case DID_TIME_OUT:
2045 /*
2046 * when we scan the bus, we get timeout messages for
2047 * these commands if there is no device available.
2048 * other hosts report did_no_connect for the same thing.
2049 */
2050 if ((scmd->cmnd[0] == TEST_UNIT_READY ||
2051 scmd->cmnd[0] == INQUIRY)) {
2052 return SUCCESS;
2053 } else {
2054 return FAILED;
2055 }
2056 case DID_RESET:
2057 return SUCCESS;
2058 default:
2059 return FAILED;
2060 }
2061
2062 /*
2063 * check the status byte to see if this indicates anything special.
2064 */
2065 switch (get_status_byte(scmd)) {
2066 case SAM_STAT_TASK_SET_FULL:
2067 scsi_handle_queue_full(scmd->device);
2068 /*
2069 * the case of trying to send too many commands to a
2070 * tagged queueing device.
2071 */
2072 fallthrough;
2073 case SAM_STAT_BUSY:
2074 /*
2075 * device can't talk to us at the moment. Should only
2076 * occur (SAM-3) when the task queue is empty, so will cause
2077 * the empty queue handling to trigger a stall in the
2078 * device.
2079 */
2080 return ADD_TO_MLQUEUE;
2081 case SAM_STAT_GOOD:
2082 if (scmd->cmnd[0] == REPORT_LUNS)
2083 scmd->device->sdev_target->expecting_lun_change = 0;
2084 scsi_handle_queue_ramp_up(scmd->device);
2085 if (scmd->sense_buffer && SCSI_SENSE_VALID(scmd))
2086 /*
2087 * If we have sense data, call scsi_check_sense() in
2088 * order to set the correct SCSI ML byte (if any).
2089 * No point in checking the return value, since the
2090 * command has already completed successfully.
2091 */
2092 scsi_check_sense(scmd);
2093 fallthrough;
2094 case SAM_STAT_COMMAND_TERMINATED:
2095 return SUCCESS;
2096 case SAM_STAT_TASK_ABORTED:
2097 goto maybe_retry;
2098 case SAM_STAT_CHECK_CONDITION:
2099 rtn = scsi_check_sense(scmd);
2100 if (rtn == NEEDS_RETRY)
2101 goto maybe_retry;
2102 /* if rtn == FAILED, we have no sense information;
2103 * returning FAILED will wake the error handler thread
2104 * to collect the sense and redo the decide
2105 * disposition */
2106 return rtn;
2107 case SAM_STAT_CONDITION_MET:
2108 case SAM_STAT_INTERMEDIATE:
2109 case SAM_STAT_INTERMEDIATE_CONDITION_MET:
2110 case SAM_STAT_ACA_ACTIVE:
2111 /*
2112 * who knows? FIXME(eric)
2113 */
2114 return SUCCESS;
2115
2116 case SAM_STAT_RESERVATION_CONFLICT:
2117 sdev_printk(KERN_INFO, scmd->device,
2118 "reservation conflict\n");
2119 set_scsi_ml_byte(scmd, SCSIML_STAT_RESV_CONFLICT);
2120 return SUCCESS; /* causes immediate i/o error */
2121 }
2122 return FAILED;
2123
2124maybe_retry:
2125
2126 /* we requeue for retry because the error was retryable, and
2127 * the request was not marked fast fail. Note that above,
2128 * even if the request is marked fast fail, we still requeue
2129 * for queue congestion conditions (QUEUE_FULL or BUSY) */
2130 if (scsi_cmd_retry_allowed(scmd) && !scsi_noretry_cmd(scmd)) {
2131 return NEEDS_RETRY;
2132 } else {
2133 /*
2134 * no more retries - report this one back to upper level.
2135 */
2136 return SUCCESS;
2137 }
2138}
2139
2140static enum rq_end_io_ret eh_lock_door_done(struct request *req,
2141 blk_status_t status,
2142 const struct io_comp_batch *iob)
2143{
2144 blk_mq_free_request(req);
2145 return RQ_END_IO_NONE;
2146}
2147
2148/**
2149 * scsi_eh_lock_door - Prevent medium removal for the specified device
2150 * @sdev: SCSI device to prevent medium removal
2151 *
2152 * Locking:
2153 * We must be called from process context.
2154 *
2155 * Notes:
2156 * We queue up an asynchronous "ALLOW MEDIUM REMOVAL" request on the
2157 * head of the devices request queue, and continue.
2158 */
2159static void scsi_eh_lock_door(struct scsi_device *sdev)
2160{
2161 struct scsi_cmnd *scmd;
2162 struct request *req;
2163
2164 req = scsi_alloc_request(sdev->request_queue, REQ_OP_DRV_IN, BLK_MQ_REQ_NOWAIT);
2165 if (IS_ERR(req))
2166 return;
2167 scmd = blk_mq_rq_to_pdu(req);
2168
2169 scmd->cmnd[0] = ALLOW_MEDIUM_REMOVAL;
2170 scmd->cmnd[1] = 0;
2171 scmd->cmnd[2] = 0;
2172 scmd->cmnd[3] = 0;
2173 scmd->cmnd[4] = SCSI_REMOVAL_PREVENT;
2174 scmd->cmnd[5] = 0;
2175 scmd->cmd_len = COMMAND_SIZE(scmd->cmnd[0]);
2176 scmd->allowed = 5;
2177
2178 req->rq_flags |= RQF_QUIET;
2179 req->timeout = 10 * HZ;
2180 req->end_io = eh_lock_door_done;
2181
2182 blk_execute_rq_nowait(req, true);
2183}
2184
2185/**
2186 * scsi_restart_operations - restart io operations to the specified host.
2187 * @shost: Host we are restarting.
2188 *
2189 * Notes:
2190 * When we entered the error handler, we blocked all further i/o to
2191 * this device. we need to 'reverse' this process.
2192 */
2193static void scsi_restart_operations(struct Scsi_Host *shost)
2194{
2195 struct scsi_device *sdev;
2196 unsigned long flags;
2197
2198 /*
2199 * If the door was locked, we need to insert a door lock request
2200 * onto the head of the SCSI request queue for the device. There
2201 * is no point trying to lock the door of an off-line device.
2202 */
2203 shost_for_each_device(sdev, shost) {
2204 if (scsi_device_online(sdev) && sdev->was_reset && sdev->locked) {
2205 scsi_eh_lock_door(sdev);
2206 sdev->was_reset = 0;
2207 }
2208 }
2209
2210 /*
2211 * next free up anything directly waiting upon the host. this
2212 * will be requests for character device operations, and also for
2213 * ioctls to queued block devices.
2214 */
2215 SCSI_LOG_ERROR_RECOVERY(3,
2216 shost_printk(KERN_INFO, shost, "waking up host to restart\n"));
2217
2218 spin_lock_irqsave(shost->host_lock, flags);
2219 if (scsi_host_set_state(shost, SHOST_RUNNING))
2220 if (scsi_host_set_state(shost, SHOST_CANCEL))
2221 BUG_ON(scsi_host_set_state(shost, SHOST_DEL));
2222 spin_unlock_irqrestore(shost->host_lock, flags);
2223
2224 wake_up(&shost->host_wait);
2225
2226 /*
2227 * finally we need to re-initiate requests that may be pending. we will
2228 * have had everything blocked while error handling is taking place, and
2229 * now that error recovery is done, we will need to ensure that these
2230 * requests are started.
2231 */
2232 scsi_run_host_queues(shost);
2233
2234 /*
2235 * if eh is active and host_eh_scheduled is pending we need to re-run
2236 * recovery. we do this check after scsi_run_host_queues() to allow
2237 * everything pent up since the last eh run a chance to make forward
2238 * progress before we sync again. Either we'll immediately re-run
2239 * recovery or scsi_device_unbusy() will wake us again when these
2240 * pending commands complete.
2241 */
2242 spin_lock_irqsave(shost->host_lock, flags);
2243 if (shost->host_eh_scheduled)
2244 if (scsi_host_set_state(shost, SHOST_RECOVERY))
2245 WARN_ON(scsi_host_set_state(shost, SHOST_CANCEL_RECOVERY));
2246 spin_unlock_irqrestore(shost->host_lock, flags);
2247}
2248
2249/**
2250 * scsi_eh_ready_devs - check device ready state and recover if not.
2251 * @shost: host to be recovered.
2252 * @work_q: &list_head for pending commands.
2253 * @done_q: &list_head for processed commands.
2254 */
2255void scsi_eh_ready_devs(struct Scsi_Host *shost,
2256 struct list_head *work_q,
2257 struct list_head *done_q)
2258{
2259 if (!scsi_eh_stu(shost, work_q, done_q))
2260 if (!scsi_eh_bus_device_reset(shost, work_q, done_q))
2261 if (!scsi_eh_target_reset(shost, work_q, done_q))
2262 if (!scsi_eh_bus_reset(shost, work_q, done_q))
2263 if (!scsi_eh_host_reset(shost, work_q, done_q))
2264 scsi_eh_offline_sdevs(work_q,
2265 done_q);
2266}
2267EXPORT_SYMBOL_GPL(scsi_eh_ready_devs);
2268
2269/**
2270 * scsi_eh_flush_done_q - finish processed commands or retry them.
2271 * @done_q: list_head of processed commands.
2272 */
2273void scsi_eh_flush_done_q(struct list_head *done_q)
2274{
2275 struct scsi_cmnd *scmd, *next;
2276
2277 list_for_each_entry_safe(scmd, next, done_q, eh_entry) {
2278 struct scsi_device *sdev = scmd->device;
2279
2280 list_del_init(&scmd->eh_entry);
2281 if (scsi_device_online(sdev) && !scsi_noretry_cmd(scmd) &&
2282 scsi_cmd_retry_allowed(scmd) &&
2283 scsi_eh_should_retry_cmd(scmd)) {
2284 SCSI_LOG_ERROR_RECOVERY(3,
2285 scmd_printk(KERN_INFO, scmd,
2286 "%s: flush retry cmd\n",
2287 current->comm));
2288 scsi_queue_insert(scmd, SCSI_MLQUEUE_EH_RETRY);
2289 blk_mq_kick_requeue_list(sdev->request_queue);
2290 } else {
2291 /*
2292 * If just we got sense for the device (called
2293 * scsi_eh_get_sense), scmd->result is already
2294 * set, do not set DID_TIME_OUT.
2295 */
2296 if (!scmd->result &&
2297 !(scmd->flags & SCMD_FORCE_EH_SUCCESS))
2298 scmd->result |= (DID_TIME_OUT << 16);
2299 SCSI_LOG_ERROR_RECOVERY(3,
2300 scmd_printk(KERN_INFO, scmd,
2301 "%s: flush finish cmd\n",
2302 current->comm));
2303 scsi_finish_command(scmd);
2304 }
2305 }
2306}
2307EXPORT_SYMBOL(scsi_eh_flush_done_q);
2308
2309/**
2310 * scsi_unjam_host - Attempt to fix a host which has a cmd that failed.
2311 * @shost: Host to unjam.
2312 *
2313 * Notes:
2314 * When we come in here, we *know* that all commands on the bus have
2315 * either completed, failed or timed out. we also know that no further
2316 * commands are being sent to the host, so things are relatively quiet
2317 * and we have freedom to fiddle with things as we wish.
2318 *
2319 * This is only the *default* implementation. it is possible for
2320 * individual drivers to supply their own version of this function, and
2321 * if the maintainer wishes to do this, it is strongly suggested that
2322 * this function be taken as a template and modified. this function
2323 * was designed to correctly handle problems for about 95% of the
2324 * different cases out there, and it should always provide at least a
2325 * reasonable amount of error recovery.
2326 *
2327 * Any command marked 'failed' or 'timeout' must eventually have
2328 * scsi_finish_cmd() called for it. we do all of the retry stuff
2329 * here, so when we restart the host after we return it should have an
2330 * empty queue.
2331 */
2332static void scsi_unjam_host(struct Scsi_Host *shost)
2333{
2334 unsigned long flags;
2335 LIST_HEAD(eh_work_q);
2336 LIST_HEAD(eh_done_q);
2337
2338 spin_lock_irqsave(shost->host_lock, flags);
2339 list_splice_init(&shost->eh_cmd_q, &eh_work_q);
2340 spin_unlock_irqrestore(shost->host_lock, flags);
2341
2342 SCSI_LOG_ERROR_RECOVERY(1, scsi_eh_prt_fail_stats(shost, &eh_work_q));
2343
2344 if (!scsi_eh_get_sense(&eh_work_q, &eh_done_q))
2345 scsi_eh_ready_devs(shost, &eh_work_q, &eh_done_q);
2346
2347 spin_lock_irqsave(shost->host_lock, flags);
2348 if (shost->eh_deadline != -1)
2349 shost->last_reset = 0;
2350 spin_unlock_irqrestore(shost->host_lock, flags);
2351 scsi_eh_flush_done_q(&eh_done_q);
2352}
2353
2354/**
2355 * scsi_error_handler - SCSI error handler thread
2356 * @data: Host for which we are running.
2357 *
2358 * Notes:
2359 * This is the main error handling loop. This is run as a kernel thread
2360 * for every SCSI host and handles all error handling activity.
2361 */
2362int scsi_error_handler(void *data)
2363{
2364 struct Scsi_Host *shost = data;
2365 bool eh_noresume;
2366
2367 /*
2368 * We use TASK_INTERRUPTIBLE so that the thread is not
2369 * counted against the load average as a running process.
2370 * We never actually get interrupted because kthread_run
2371 * disables signal delivery for the created thread.
2372 */
2373 while (true) {
2374 /*
2375 * The sequence in kthread_stop() sets the stop flag first
2376 * then wakes the process. To avoid missed wakeups, the task
2377 * should always be in a non running state before the stop
2378 * flag is checked
2379 */
2380 set_current_state(TASK_INTERRUPTIBLE);
2381 if (kthread_should_stop())
2382 break;
2383
2384 if ((shost->host_failed == 0 && shost->host_eh_scheduled == 0) ||
2385 shost->host_failed != scsi_host_busy(shost)) {
2386 SCSI_LOG_ERROR_RECOVERY(1,
2387 shost_printk(KERN_INFO, shost,
2388 "scsi_eh_%d: sleeping\n",
2389 shost->host_no));
2390 schedule();
2391 continue;
2392 }
2393
2394 __set_current_state(TASK_RUNNING);
2395 SCSI_LOG_ERROR_RECOVERY(1,
2396 shost_printk(KERN_INFO, shost,
2397 "scsi_eh_%d: waking up %d/%d/%d\n",
2398 shost->host_no, shost->host_eh_scheduled,
2399 shost->host_failed,
2400 scsi_host_busy(shost)));
2401
2402 /*
2403 * We have a host that is failing for some reason. Figure out
2404 * what we need to do to get it up and online again (if we can).
2405 * If we fail, we end up taking the thing offline.
2406 */
2407 eh_noresume = READ_ONCE(shost->eh_noresume);
2408 if (!eh_noresume && scsi_autopm_get_host(shost) != 0) {
2409 SCSI_LOG_ERROR_RECOVERY(1,
2410 shost_printk(KERN_ERR, shost,
2411 "scsi_eh_%d: unable to autoresume\n",
2412 shost->host_no));
2413 continue;
2414 }
2415
2416 if (shost->transportt->eh_strategy_handler)
2417 shost->transportt->eh_strategy_handler(shost);
2418 else
2419 scsi_unjam_host(shost);
2420
2421 /* All scmds have been handled */
2422 shost->host_failed = 0;
2423
2424 /*
2425 * Note - if the above fails completely, the action is to take
2426 * individual devices offline and flush the queue of any
2427 * outstanding requests that may have been pending. When we
2428 * restart, we restart any I/O to any other devices on the bus
2429 * which are still online.
2430 */
2431 scsi_restart_operations(shost);
2432 if (!eh_noresume)
2433 scsi_autopm_put_host(shost);
2434 }
2435 __set_current_state(TASK_RUNNING);
2436
2437 SCSI_LOG_ERROR_RECOVERY(1,
2438 shost_printk(KERN_INFO, shost,
2439 "Error handler scsi_eh_%d exiting\n",
2440 shost->host_no));
2441 shost->ehandler = NULL;
2442 return 0;
2443}
2444
2445/**
2446 * scsi_report_bus_reset() - report bus reset observed
2447 *
2448 * Utility function used by low-level drivers to report that
2449 * they have observed a bus reset on the bus being handled.
2450 *
2451 * @shost: Host in question
2452 * @channel: channel on which reset was observed.
2453 *
2454 * Returns: Nothing
2455 *
2456 * Lock status: Host lock must be held.
2457 *
2458 * Notes: This only needs to be called if the reset is one which
2459 * originates from an unknown location. Resets originated
2460 * by the mid-level itself don't need to call this, but there
2461 * should be no harm.
2462 *
2463 * The main purpose of this is to make sure that a CHECK_CONDITION
2464 * is properly treated.
2465 */
2466void scsi_report_bus_reset(struct Scsi_Host *shost, int channel)
2467{
2468 struct scsi_device *sdev;
2469
2470 __shost_for_each_device(sdev, shost) {
2471 if (channel == sdev_channel(sdev))
2472 __scsi_report_device_reset(sdev, NULL);
2473 }
2474}
2475EXPORT_SYMBOL(scsi_report_bus_reset);
2476
2477/**
2478 * scsi_report_device_reset() - report device reset observed
2479 *
2480 * Utility function used by low-level drivers to report that
2481 * they have observed a device reset on the device being handled.
2482 *
2483 * @shost: Host in question
2484 * @channel: channel on which reset was observed
2485 * @target: target on which reset was observed
2486 *
2487 * Returns: Nothing
2488 *
2489 * Lock status: Host lock must be held
2490 *
2491 * Notes: This only needs to be called if the reset is one which
2492 * originates from an unknown location. Resets originated
2493 * by the mid-level itself don't need to call this, but there
2494 * should be no harm.
2495 *
2496 * The main purpose of this is to make sure that a CHECK_CONDITION
2497 * is properly treated.
2498 */
2499void scsi_report_device_reset(struct Scsi_Host *shost, int channel, int target)
2500{
2501 struct scsi_device *sdev;
2502
2503 __shost_for_each_device(sdev, shost) {
2504 if (channel == sdev_channel(sdev) &&
2505 target == sdev_id(sdev))
2506 __scsi_report_device_reset(sdev, NULL);
2507 }
2508}
2509EXPORT_SYMBOL(scsi_report_device_reset);
2510
2511/**
2512 * scsi_ioctl_reset: explicitly reset a host/bus/target/device
2513 * @dev: scsi_device to operate on
2514 * @arg: reset type (see sg.h)
2515 */
2516int
2517scsi_ioctl_reset(struct scsi_device *dev, int __user *arg)
2518{
2519 struct scsi_cmnd *scmd;
2520 struct Scsi_Host *shost = dev->host;
2521 struct request *rq;
2522 unsigned long flags;
2523 int error = 0, val;
2524 enum scsi_disposition rtn;
2525
2526 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2527 return -EACCES;
2528
2529 error = get_user(val, arg);
2530 if (error)
2531 return error;
2532
2533 if (scsi_autopm_get_host(shost) < 0)
2534 return -EIO;
2535
2536 error = -EIO;
2537 rq = kzalloc(sizeof(struct request) + sizeof(struct scsi_cmnd) +
2538 shost->hostt->cmd_size, GFP_KERNEL);
2539 if (!rq)
2540 goto out_put_autopm_host;
2541 blk_rq_init(NULL, rq);
2542
2543 scmd = (struct scsi_cmnd *)(rq + 1);
2544 scsi_init_command(dev, scmd);
2545
2546 scmd->submitter = SUBMITTED_BY_SCSI_RESET_IOCTL;
2547 scmd->flags |= SCMD_LAST;
2548 memset(&scmd->sdb, 0, sizeof(scmd->sdb));
2549
2550 scmd->cmd_len = 0;
2551
2552 scmd->sc_data_direction = DMA_BIDIRECTIONAL;
2553
2554 spin_lock_irqsave(shost->host_lock, flags);
2555 shost->tmf_in_progress = 1;
2556 spin_unlock_irqrestore(shost->host_lock, flags);
2557
2558 switch (val & ~SG_SCSI_RESET_NO_ESCALATE) {
2559 case SG_SCSI_RESET_NOTHING:
2560 rtn = SUCCESS;
2561 break;
2562 case SG_SCSI_RESET_DEVICE:
2563 rtn = scsi_try_bus_device_reset(scmd);
2564 if (rtn == SUCCESS || (val & SG_SCSI_RESET_NO_ESCALATE))
2565 break;
2566 fallthrough;
2567 case SG_SCSI_RESET_TARGET:
2568 rtn = scsi_try_target_reset(scmd);
2569 if (rtn == SUCCESS || (val & SG_SCSI_RESET_NO_ESCALATE))
2570 break;
2571 fallthrough;
2572 case SG_SCSI_RESET_BUS:
2573 rtn = scsi_try_bus_reset(scmd);
2574 if (rtn == SUCCESS || (val & SG_SCSI_RESET_NO_ESCALATE))
2575 break;
2576 fallthrough;
2577 case SG_SCSI_RESET_HOST:
2578 rtn = scsi_try_host_reset(scmd);
2579 if (rtn == SUCCESS)
2580 break;
2581 fallthrough;
2582 default:
2583 rtn = FAILED;
2584 break;
2585 }
2586
2587 error = (rtn == SUCCESS) ? 0 : -EIO;
2588
2589 spin_lock_irqsave(shost->host_lock, flags);
2590 shost->tmf_in_progress = 0;
2591 spin_unlock_irqrestore(shost->host_lock, flags);
2592
2593 /*
2594 * be sure to wake up anyone who was sleeping or had their queue
2595 * suspended while we performed the TMF.
2596 */
2597 SCSI_LOG_ERROR_RECOVERY(3,
2598 shost_printk(KERN_INFO, shost,
2599 "waking up host to restart after TMF\n"));
2600
2601 wake_up(&shost->host_wait);
2602 scsi_run_host_queues(shost);
2603
2604 kfree(rq);
2605
2606out_put_autopm_host:
2607 scsi_autopm_put_host(shost);
2608 return error;
2609}
2610
2611bool scsi_command_normalize_sense(const struct scsi_cmnd *cmd,
2612 struct scsi_sense_hdr *sshdr)
2613{
2614 return scsi_normalize_sense(cmd->sense_buffer,
2615 SCSI_SENSE_BUFFERSIZE, sshdr);
2616}
2617EXPORT_SYMBOL(scsi_command_normalize_sense);
2618
2619/**
2620 * scsi_get_sense_info_fld - get information field from sense data (either fixed or descriptor format)
2621 * @sense_buffer: byte array of sense data
2622 * @sb_len: number of valid bytes in sense_buffer
2623 * @info_out: pointer to 64 integer where 8 or 4 byte information
2624 * field will be placed if found.
2625 *
2626 * Return value:
2627 * true if information field found, false if not found.
2628 */
2629bool scsi_get_sense_info_fld(const u8 *sense_buffer, int sb_len,
2630 u64 *info_out)
2631{
2632 const u8 * ucp;
2633
2634 if (sb_len < 7)
2635 return false;
2636 switch (sense_buffer[0] & 0x7f) {
2637 case 0x70:
2638 case 0x71:
2639 if (sense_buffer[0] & 0x80) {
2640 *info_out = get_unaligned_be32(&sense_buffer[3]);
2641 return true;
2642 }
2643 return false;
2644 case 0x72:
2645 case 0x73:
2646 ucp = scsi_sense_desc_find(sense_buffer, sb_len,
2647 0 /* info desc */);
2648 if (ucp && (0xa == ucp[1])) {
2649 *info_out = get_unaligned_be64(&ucp[4]);
2650 return true;
2651 }
2652 return false;
2653 default:
2654 return false;
2655 }
2656}
2657EXPORT_SYMBOL(scsi_get_sense_info_fld);