1 // SPDX-License-Identifier: GPL-2.0-only
3 * scsi_error.c Copyright (C) 1997 Eric Youngdale
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.
10 * Restructured scsi_unjam_host and associated functions.
11 * September 04, 2002 Mike Anderson (andmike@us.ibm.com)
13 * Forward port of Russell King's (rmk@arm.linux.org.uk) changes and
15 * September 30, 2002 Mike Anderson (andmike@us.ibm.com)
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>
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>
45 #include "scsi_priv.h"
46 #include "scsi_logging.h"
47 #include "scsi_transport_api.h"
49 #include <trace/events/scsi.h>
51 #include <asm/unaligned.h>
54 * These should *probably* be handled by the host itself.
55 * Since it is allowed to sleep, it probably should.
57 #define BUS_RESET_SETTLE_TIME (10)
58 #define HOST_RESET_SETTLE_TIME (10)
60 static int scsi_eh_try_stu(struct scsi_cmnd *scmd);
61 static enum scsi_disposition scsi_try_to_abort_cmd(struct scsi_host_template *,
64 void scsi_eh_wakeup(struct Scsi_Host *shost)
66 lockdep_assert_held(shost->host_lock);
68 if (scsi_host_busy(shost) == 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"));
77 * scsi_schedule_eh - schedule EH for SCSI host
78 * @shost: SCSI host to invoke error handling on.
80 * Schedule SCSI EH without scmd.
82 void scsi_schedule_eh(struct Scsi_Host *shost)
86 spin_lock_irqsave(shost->host_lock, flags);
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);
94 spin_unlock_irqrestore(shost->host_lock, flags);
96 EXPORT_SYMBOL_GPL(scsi_schedule_eh);
98 static int scsi_host_eh_past_deadline(struct Scsi_Host *shost)
100 if (!shost->last_reset || shost->eh_deadline == -1)
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
110 if (time_before(jiffies, shost->last_reset + shost->eh_deadline) &&
111 shost->eh_deadline > -1)
117 static bool scsi_cmd_retry_allowed(struct scsi_cmnd *cmd)
119 if (cmd->allowed == SCSI_CMD_RETRIES_NO_LIMIT)
122 return ++cmd->retries <= cmd->allowed;
125 static bool scsi_eh_should_retry_cmd(struct scsi_cmnd *cmd)
127 struct scsi_device *sdev = cmd->device;
128 struct Scsi_Host *host = sdev->host;
130 if (host->hostt->eh_should_retry_cmd)
131 return host->hostt->eh_should_retry_cmd(cmd);
137 * scmd_eh_abort_handler - Handle command aborts
138 * @work: command to be aborted.
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_times_out(), 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.
147 scmd_eh_abort_handler(struct work_struct *work)
149 struct scsi_cmnd *scmd =
150 container_of(work, struct scsi_cmnd, abort_work.work);
151 struct scsi_device *sdev = scmd->device;
152 enum scsi_disposition rtn;
154 if (scsi_host_eh_past_deadline(sdev->host)) {
155 SCSI_LOG_ERROR_RECOVERY(3,
156 scmd_printk(KERN_INFO, scmd,
157 "eh timeout, not aborting\n"));
159 SCSI_LOG_ERROR_RECOVERY(3,
160 scmd_printk(KERN_INFO, scmd,
161 "aborting command\n"));
162 rtn = scsi_try_to_abort_cmd(sdev->host->hostt, scmd);
163 if (rtn == SUCCESS) {
164 set_host_byte(scmd, DID_TIME_OUT);
165 if (scsi_host_eh_past_deadline(sdev->host)) {
166 SCSI_LOG_ERROR_RECOVERY(3,
167 scmd_printk(KERN_INFO, scmd,
168 "eh timeout, not retrying "
169 "aborted command\n"));
170 } else if (!scsi_noretry_cmd(scmd) &&
171 scsi_cmd_retry_allowed(scmd) &&
172 scsi_eh_should_retry_cmd(scmd)) {
173 SCSI_LOG_ERROR_RECOVERY(3,
174 scmd_printk(KERN_WARNING, scmd,
175 "retry aborted command\n"));
176 scsi_queue_insert(scmd, SCSI_MLQUEUE_EH_RETRY);
179 SCSI_LOG_ERROR_RECOVERY(3,
180 scmd_printk(KERN_WARNING, scmd,
181 "finish aborted command\n"));
182 scsi_finish_command(scmd);
186 SCSI_LOG_ERROR_RECOVERY(3,
187 scmd_printk(KERN_INFO, scmd,
189 (rtn == FAST_IO_FAIL) ?
190 "not send" : "failed"));
194 scsi_eh_scmd_add(scmd);
198 * scsi_abort_command - schedule a command abort
199 * @scmd: scmd to abort.
201 * We only need to abort commands after a command timeout
204 scsi_abort_command(struct scsi_cmnd *scmd)
206 struct scsi_device *sdev = scmd->device;
207 struct Scsi_Host *shost = sdev->host;
210 if (scmd->eh_eflags & SCSI_EH_ABORT_SCHEDULED) {
212 * Retry after abort failed, escalate to next level.
214 SCSI_LOG_ERROR_RECOVERY(3,
215 scmd_printk(KERN_INFO, scmd,
216 "previous abort failed\n"));
217 BUG_ON(delayed_work_pending(&scmd->abort_work));
221 spin_lock_irqsave(shost->host_lock, flags);
222 if (shost->eh_deadline != -1 && !shost->last_reset)
223 shost->last_reset = jiffies;
224 spin_unlock_irqrestore(shost->host_lock, flags);
226 scmd->eh_eflags |= SCSI_EH_ABORT_SCHEDULED;
227 SCSI_LOG_ERROR_RECOVERY(3,
228 scmd_printk(KERN_INFO, scmd, "abort scheduled\n"));
229 queue_delayed_work(shost->tmf_work_q, &scmd->abort_work, HZ / 100);
234 * scsi_eh_reset - call into ->eh_action to reset internal counters
235 * @scmd: scmd to run eh on.
237 * The scsi driver might be carrying internal state about the
238 * devices, so we need to call into the driver to reset the
239 * internal state once the error handler is started.
241 static void scsi_eh_reset(struct scsi_cmnd *scmd)
243 if (!blk_rq_is_passthrough(scsi_cmd_to_rq(scmd))) {
244 struct scsi_driver *sdrv = scsi_cmd_to_driver(scmd);
246 sdrv->eh_reset(scmd);
250 static void scsi_eh_inc_host_failed(struct rcu_head *head)
252 struct scsi_cmnd *scmd = container_of(head, typeof(*scmd), rcu);
253 struct Scsi_Host *shost = scmd->device->host;
256 spin_lock_irqsave(shost->host_lock, flags);
257 shost->host_failed++;
258 scsi_eh_wakeup(shost);
259 spin_unlock_irqrestore(shost->host_lock, flags);
263 * scsi_eh_scmd_add - add scsi cmd to error handling.
264 * @scmd: scmd to run eh on.
266 void scsi_eh_scmd_add(struct scsi_cmnd *scmd)
268 struct Scsi_Host *shost = scmd->device->host;
272 WARN_ON_ONCE(!shost->ehandler);
274 spin_lock_irqsave(shost->host_lock, flags);
275 if (scsi_host_set_state(shost, SHOST_RECOVERY)) {
276 ret = scsi_host_set_state(shost, SHOST_CANCEL_RECOVERY);
279 if (shost->eh_deadline != -1 && !shost->last_reset)
280 shost->last_reset = jiffies;
283 list_add_tail(&scmd->eh_entry, &shost->eh_cmd_q);
284 spin_unlock_irqrestore(shost->host_lock, flags);
286 * Ensure that all tasks observe the host state change before the
287 * host_failed change.
289 call_rcu(&scmd->rcu, scsi_eh_inc_host_failed);
293 * scsi_times_out - Timeout function for normal scsi commands.
294 * @req: request that is timing out.
297 * We do not need to lock this. There is the potential for a race
298 * only in that the normal completion handling might run, but if the
299 * normal completion function determines that the timer has already
300 * fired, then it mustn't do anything.
302 enum blk_eh_timer_return scsi_times_out(struct request *req)
304 struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(req);
305 enum blk_eh_timer_return rtn = BLK_EH_DONE;
306 struct Scsi_Host *host = scmd->device->host;
308 trace_scsi_dispatch_cmd_timeout(scmd);
309 scsi_log_completion(scmd, TIMEOUT_ERROR);
311 if (host->eh_deadline != -1 && !host->last_reset)
312 host->last_reset = jiffies;
314 if (host->hostt->eh_timed_out)
315 rtn = host->hostt->eh_timed_out(scmd);
317 if (rtn == BLK_EH_DONE) {
319 * Set the command to complete first in order to prevent a real
320 * completion from releasing the command while error handling
321 * is using it. If the command was already completed, then the
322 * lower level driver beat the timeout handler, and it is safe
323 * to return without escalating error recovery.
325 * If timeout handling lost the race to a real completion, the
326 * block layer may ignore that due to a fake timeout injection,
327 * so return RESET_TIMER to allow error handling another shot
330 if (test_and_set_bit(SCMD_STATE_COMPLETE, &scmd->state))
331 return BLK_EH_RESET_TIMER;
332 if (scsi_abort_command(scmd) != SUCCESS) {
333 set_host_byte(scmd, DID_TIME_OUT);
334 scsi_eh_scmd_add(scmd);
342 * scsi_block_when_processing_errors - Prevent cmds from being queued.
343 * @sdev: Device on which we are performing recovery.
346 * We block until the host is out of error recovery, and then check to
347 * see whether the host or the device is offline.
350 * 0 when dev was taken offline by error recovery. 1 OK to proceed.
352 int scsi_block_when_processing_errors(struct scsi_device *sdev)
356 wait_event(sdev->host->host_wait, !scsi_host_in_recovery(sdev->host));
358 online = scsi_device_online(sdev);
362 EXPORT_SYMBOL(scsi_block_when_processing_errors);
364 #ifdef CONFIG_SCSI_LOGGING
366 * scsi_eh_prt_fail_stats - Log info on failures.
367 * @shost: scsi host being recovered.
368 * @work_q: Queue of scsi cmds to process.
370 static inline void scsi_eh_prt_fail_stats(struct Scsi_Host *shost,
371 struct list_head *work_q)
373 struct scsi_cmnd *scmd;
374 struct scsi_device *sdev;
375 int total_failures = 0;
378 int devices_failed = 0;
380 shost_for_each_device(sdev, shost) {
381 list_for_each_entry(scmd, work_q, eh_entry) {
382 if (scmd->device == sdev) {
384 if (scmd->eh_eflags & SCSI_EH_ABORT_SCHEDULED)
391 if (cmd_cancel || cmd_failed) {
392 SCSI_LOG_ERROR_RECOVERY(3,
393 shost_printk(KERN_INFO, shost,
394 "%s: cmds failed: %d, cancel: %d\n",
395 __func__, cmd_failed,
403 SCSI_LOG_ERROR_RECOVERY(2, shost_printk(KERN_INFO, shost,
404 "Total of %d commands on %d"
405 " devices require eh work\n",
406 total_failures, devices_failed));
411 * scsi_report_lun_change - Set flag on all *other* devices on the same target
412 * to indicate that a UNIT ATTENTION is expected.
413 * @sdev: Device reporting the UNIT ATTENTION
415 static void scsi_report_lun_change(struct scsi_device *sdev)
417 sdev->sdev_target->expecting_lun_change = 1;
421 * scsi_report_sense - Examine scsi sense information and log messages for
422 * certain conditions, also issue uevents for some of them.
423 * @sdev: Device reporting the sense code
424 * @sshdr: sshdr to be examined
426 static void scsi_report_sense(struct scsi_device *sdev,
427 struct scsi_sense_hdr *sshdr)
429 enum scsi_device_event evt_type = SDEV_EVT_MAXBITS; /* i.e. none */
431 if (sshdr->sense_key == UNIT_ATTENTION) {
432 if (sshdr->asc == 0x3f && sshdr->ascq == 0x03) {
433 evt_type = SDEV_EVT_INQUIRY_CHANGE_REPORTED;
434 sdev_printk(KERN_WARNING, sdev,
435 "Inquiry data has changed");
436 } else if (sshdr->asc == 0x3f && sshdr->ascq == 0x0e) {
437 evt_type = SDEV_EVT_LUN_CHANGE_REPORTED;
438 scsi_report_lun_change(sdev);
439 sdev_printk(KERN_WARNING, sdev,
440 "Warning! Received an indication that the "
441 "LUN assignments on this target have "
442 "changed. The Linux SCSI layer does not "
443 "automatically remap LUN assignments.\n");
444 } else if (sshdr->asc == 0x3f)
445 sdev_printk(KERN_WARNING, sdev,
446 "Warning! Received an indication that the "
447 "operating parameters on this target have "
448 "changed. The Linux SCSI layer does not "
449 "automatically adjust these parameters.\n");
451 if (sshdr->asc == 0x38 && sshdr->ascq == 0x07) {
452 evt_type = SDEV_EVT_SOFT_THRESHOLD_REACHED_REPORTED;
453 sdev_printk(KERN_WARNING, sdev,
454 "Warning! Received an indication that the "
455 "LUN reached a thin provisioning soft "
459 if (sshdr->asc == 0x29) {
460 evt_type = SDEV_EVT_POWER_ON_RESET_OCCURRED;
461 sdev_printk(KERN_WARNING, sdev,
462 "Power-on or device reset occurred\n");
465 if (sshdr->asc == 0x2a && sshdr->ascq == 0x01) {
466 evt_type = SDEV_EVT_MODE_PARAMETER_CHANGE_REPORTED;
467 sdev_printk(KERN_WARNING, sdev,
468 "Mode parameters changed");
469 } else if (sshdr->asc == 0x2a && sshdr->ascq == 0x06) {
470 evt_type = SDEV_EVT_ALUA_STATE_CHANGE_REPORTED;
471 sdev_printk(KERN_WARNING, sdev,
472 "Asymmetric access state changed");
473 } else if (sshdr->asc == 0x2a && sshdr->ascq == 0x09) {
474 evt_type = SDEV_EVT_CAPACITY_CHANGE_REPORTED;
475 sdev_printk(KERN_WARNING, sdev,
476 "Capacity data has changed");
477 } else if (sshdr->asc == 0x2a)
478 sdev_printk(KERN_WARNING, sdev,
479 "Parameters changed");
482 if (evt_type != SDEV_EVT_MAXBITS) {
483 set_bit(evt_type, sdev->pending_events);
484 schedule_work(&sdev->event_work);
489 * scsi_check_sense - Examine scsi cmd sense
490 * @scmd: Cmd to have sense checked.
493 * SUCCESS or FAILED or NEEDS_RETRY or ADD_TO_MLQUEUE
496 * When a deferred error is detected the current command has
497 * not been executed and needs retrying.
499 enum scsi_disposition scsi_check_sense(struct scsi_cmnd *scmd)
501 struct scsi_device *sdev = scmd->device;
502 struct scsi_sense_hdr sshdr;
504 if (! scsi_command_normalize_sense(scmd, &sshdr))
505 return FAILED; /* no valid sense data */
507 scsi_report_sense(sdev, &sshdr);
509 if (scsi_sense_is_deferred(&sshdr))
512 if (sdev->handler && sdev->handler->check_sense) {
513 enum scsi_disposition rc;
515 rc = sdev->handler->check_sense(sdev, &sshdr);
516 if (rc != SCSI_RETURN_NOT_HANDLED)
518 /* handler does not care. Drop down to default handling */
521 if (scmd->cmnd[0] == TEST_UNIT_READY &&
522 scmd->submitter != SUBMITTED_BY_SCSI_ERROR_HANDLER)
524 * nasty: for mid-layer issued TURs, we need to return the
525 * actual sense data without any recovery attempt. For eh
526 * issued ones, we need to try to recover and interpret
531 * Previous logic looked for FILEMARK, EOM or ILI which are
532 * mainly associated with tapes and returned SUCCESS.
534 if (sshdr.response_code == 0x70) {
536 if (scmd->sense_buffer[2] & 0xe0)
540 * descriptor format: look for "stream commands sense data
541 * descriptor" (see SSC-3). Assume single sense data
542 * descriptor. Ignore ILI from SBC-2 READ LONG and WRITE LONG.
544 if ((sshdr.additional_length > 3) &&
545 (scmd->sense_buffer[8] == 0x4) &&
546 (scmd->sense_buffer[11] & 0xe0))
550 switch (sshdr.sense_key) {
553 case RECOVERED_ERROR:
554 return /* soft_error */ SUCCESS;
556 case ABORTED_COMMAND:
557 if (sshdr.asc == 0x10) /* DIF */
560 if (sshdr.asc == 0x44 && sdev->sdev_bflags & BLIST_RETRY_ITF)
561 return ADD_TO_MLQUEUE;
562 if (sshdr.asc == 0xc1 && sshdr.ascq == 0x01 &&
563 sdev->sdev_bflags & BLIST_RETRY_ASC_C1)
564 return ADD_TO_MLQUEUE;
570 * if we are expecting a cc/ua because of a bus reset that we
571 * performed, treat this just as a retry. otherwise this is
572 * information that we should pass up to the upper-level driver
573 * so that we can deal with it there.
575 if (scmd->device->expecting_cc_ua) {
577 * Because some device does not queue unit
578 * attentions correctly, we carefully check
579 * additional sense code and qualifier so as
580 * not to squash media change unit attention.
582 if (sshdr.asc != 0x28 || sshdr.ascq != 0x00) {
583 scmd->device->expecting_cc_ua = 0;
588 * we might also expect a cc/ua if another LUN on the target
589 * reported a UA with an ASC/ASCQ of 3F 0E -
590 * REPORTED LUNS DATA HAS CHANGED.
592 if (scmd->device->sdev_target->expecting_lun_change &&
593 sshdr.asc == 0x3f && sshdr.ascq == 0x0e)
596 * if the device is in the process of becoming ready, we
599 if ((sshdr.asc == 0x04) && (sshdr.ascq == 0x01))
602 * if the device is not started, we need to wake
603 * the error handler to start the motor
605 if (scmd->device->allow_restart &&
606 (sshdr.asc == 0x04) && (sshdr.ascq == 0x02))
609 * Pass the UA upwards for a determination in the completion
614 /* these are not supported */
616 if (sshdr.asc == 0x27 && sshdr.ascq == 0x07) {
617 /* Thin provisioning hard threshold reached */
618 set_host_byte(scmd, DID_ALLOC_FAILURE);
623 case VOLUME_OVERFLOW:
626 set_host_byte(scmd, DID_TARGET_FAILURE);
630 if (sshdr.asc == 0x11 || /* UNRECOVERED READ ERR */
631 sshdr.asc == 0x13 || /* AMNF DATA FIELD */
632 sshdr.asc == 0x14) { /* RECORD NOT FOUND */
633 set_host_byte(scmd, DID_MEDIUM_ERROR);
639 if (scmd->device->retry_hwerror)
640 return ADD_TO_MLQUEUE;
642 set_host_byte(scmd, DID_TARGET_FAILURE);
645 case ILLEGAL_REQUEST:
646 if (sshdr.asc == 0x20 || /* Invalid command operation code */
647 sshdr.asc == 0x21 || /* Logical block address out of range */
648 sshdr.asc == 0x22 || /* Invalid function */
649 sshdr.asc == 0x24 || /* Invalid field in cdb */
650 sshdr.asc == 0x26 || /* Parameter value invalid */
651 sshdr.asc == 0x27) { /* Write protected */
652 set_host_byte(scmd, DID_TARGET_FAILURE);
660 EXPORT_SYMBOL_GPL(scsi_check_sense);
662 static void scsi_handle_queue_ramp_up(struct scsi_device *sdev)
664 struct scsi_host_template *sht = sdev->host->hostt;
665 struct scsi_device *tmp_sdev;
667 if (!sht->track_queue_depth ||
668 sdev->queue_depth >= sdev->max_queue_depth)
671 if (time_before(jiffies,
672 sdev->last_queue_ramp_up + sdev->queue_ramp_up_period))
675 if (time_before(jiffies,
676 sdev->last_queue_full_time + sdev->queue_ramp_up_period))
680 * Walk all devices of a target and do
683 shost_for_each_device(tmp_sdev, sdev->host) {
684 if (tmp_sdev->channel != sdev->channel ||
685 tmp_sdev->id != sdev->id ||
686 tmp_sdev->queue_depth == sdev->max_queue_depth)
689 scsi_change_queue_depth(tmp_sdev, tmp_sdev->queue_depth + 1);
690 sdev->last_queue_ramp_up = jiffies;
694 static void scsi_handle_queue_full(struct scsi_device *sdev)
696 struct scsi_host_template *sht = sdev->host->hostt;
697 struct scsi_device *tmp_sdev;
699 if (!sht->track_queue_depth)
702 shost_for_each_device(tmp_sdev, sdev->host) {
703 if (tmp_sdev->channel != sdev->channel ||
704 tmp_sdev->id != sdev->id)
707 * We do not know the number of commands that were at
708 * the device when we got the queue full so we start
709 * from the highest possible value and work our way down.
711 scsi_track_queue_full(tmp_sdev, tmp_sdev->queue_depth - 1);
716 * scsi_eh_completed_normally - Disposition a eh cmd on return from LLD.
717 * @scmd: SCSI cmd to examine.
720 * This is *only* called when we are examining the status of commands
721 * queued during error recovery. the main difference here is that we
722 * don't allow for the possibility of retries here, and we are a lot
723 * more restrictive about what we consider acceptable.
725 static enum scsi_disposition scsi_eh_completed_normally(struct scsi_cmnd *scmd)
728 * first check the host byte, to see if there is anything in there
729 * that would indicate what we need to do.
731 if (host_byte(scmd->result) == DID_RESET) {
733 * rats. we are already in the error handler, so we now
734 * get to try and figure out what to do next. if the sense
735 * is valid, we have a pretty good idea of what to do.
736 * if not, we mark it as FAILED.
738 return scsi_check_sense(scmd);
740 if (host_byte(scmd->result) != DID_OK)
744 * now, check the status byte to see if this indicates
747 switch (get_status_byte(scmd)) {
749 scsi_handle_queue_ramp_up(scmd->device);
751 case SAM_STAT_COMMAND_TERMINATED:
753 case SAM_STAT_CHECK_CONDITION:
754 return scsi_check_sense(scmd);
755 case SAM_STAT_CONDITION_MET:
756 case SAM_STAT_INTERMEDIATE:
757 case SAM_STAT_INTERMEDIATE_CONDITION_MET:
759 * who knows? FIXME(eric)
762 case SAM_STAT_RESERVATION_CONFLICT:
763 if (scmd->cmnd[0] == TEST_UNIT_READY)
764 /* it is a success, we probed the device and
767 /* otherwise, we failed to send the command */
769 case SAM_STAT_TASK_SET_FULL:
770 scsi_handle_queue_full(scmd->device);
781 * scsi_eh_done - Completion function for error handling.
782 * @scmd: Cmd that is done.
784 void scsi_eh_done(struct scsi_cmnd *scmd)
786 struct completion *eh_action;
788 SCSI_LOG_ERROR_RECOVERY(3, scmd_printk(KERN_INFO, scmd,
789 "%s result: %x\n", __func__, scmd->result));
791 eh_action = scmd->device->host->eh_action;
797 * scsi_try_host_reset - ask host adapter to reset itself
798 * @scmd: SCSI cmd to send host reset.
800 static enum scsi_disposition scsi_try_host_reset(struct scsi_cmnd *scmd)
803 enum scsi_disposition rtn;
804 struct Scsi_Host *host = scmd->device->host;
805 struct scsi_host_template *hostt = host->hostt;
807 SCSI_LOG_ERROR_RECOVERY(3,
808 shost_printk(KERN_INFO, host, "Snd Host RST\n"));
810 if (!hostt->eh_host_reset_handler)
813 rtn = hostt->eh_host_reset_handler(scmd);
815 if (rtn == SUCCESS) {
816 if (!hostt->skip_settle_delay)
817 ssleep(HOST_RESET_SETTLE_TIME);
818 spin_lock_irqsave(host->host_lock, flags);
819 scsi_report_bus_reset(host, scmd_channel(scmd));
820 spin_unlock_irqrestore(host->host_lock, flags);
827 * scsi_try_bus_reset - ask host to perform a bus reset
828 * @scmd: SCSI cmd to send bus reset.
830 static enum scsi_disposition scsi_try_bus_reset(struct scsi_cmnd *scmd)
833 enum scsi_disposition rtn;
834 struct Scsi_Host *host = scmd->device->host;
835 struct scsi_host_template *hostt = host->hostt;
837 SCSI_LOG_ERROR_RECOVERY(3, scmd_printk(KERN_INFO, scmd,
838 "%s: Snd Bus RST\n", __func__));
840 if (!hostt->eh_bus_reset_handler)
843 rtn = hostt->eh_bus_reset_handler(scmd);
845 if (rtn == SUCCESS) {
846 if (!hostt->skip_settle_delay)
847 ssleep(BUS_RESET_SETTLE_TIME);
848 spin_lock_irqsave(host->host_lock, flags);
849 scsi_report_bus_reset(host, scmd_channel(scmd));
850 spin_unlock_irqrestore(host->host_lock, flags);
856 static void __scsi_report_device_reset(struct scsi_device *sdev, void *data)
859 sdev->expecting_cc_ua = 1;
863 * scsi_try_target_reset - Ask host to perform a target reset
864 * @scmd: SCSI cmd used to send a target reset
867 * There is no timeout for this operation. if this operation is
868 * unreliable for a given host, then the host itself needs to put a
869 * timer on it, and set the host back to a consistent state prior to
872 static enum scsi_disposition scsi_try_target_reset(struct scsi_cmnd *scmd)
875 enum scsi_disposition rtn;
876 struct Scsi_Host *host = scmd->device->host;
877 struct scsi_host_template *hostt = host->hostt;
879 if (!hostt->eh_target_reset_handler)
882 rtn = hostt->eh_target_reset_handler(scmd);
883 if (rtn == SUCCESS) {
884 spin_lock_irqsave(host->host_lock, flags);
885 __starget_for_each_device(scsi_target(scmd->device), NULL,
886 __scsi_report_device_reset);
887 spin_unlock_irqrestore(host->host_lock, flags);
894 * scsi_try_bus_device_reset - Ask host to perform a BDR on a dev
895 * @scmd: SCSI cmd used to send BDR
898 * There is no timeout for this operation. if this operation is
899 * unreliable for a given host, then the host itself needs to put a
900 * timer on it, and set the host back to a consistent state prior to
903 static enum scsi_disposition scsi_try_bus_device_reset(struct scsi_cmnd *scmd)
905 enum scsi_disposition rtn;
906 struct scsi_host_template *hostt = scmd->device->host->hostt;
908 if (!hostt->eh_device_reset_handler)
911 rtn = hostt->eh_device_reset_handler(scmd);
913 __scsi_report_device_reset(scmd->device, NULL);
918 * scsi_try_to_abort_cmd - Ask host to abort a SCSI command
919 * @hostt: SCSI driver host template
920 * @scmd: SCSI cmd used to send a target reset
923 * SUCCESS, FAILED, or FAST_IO_FAIL
926 * SUCCESS does not necessarily indicate that the command
927 * has been aborted; it only indicates that the LLDDs
928 * has cleared all references to that command.
929 * LLDDs should return FAILED only if an abort was required
930 * but could not be executed. LLDDs should return FAST_IO_FAIL
931 * if the device is temporarily unavailable (eg due to a
932 * link down on FibreChannel)
934 static enum scsi_disposition
935 scsi_try_to_abort_cmd(struct scsi_host_template *hostt, struct scsi_cmnd *scmd)
937 if (!hostt->eh_abort_handler)
940 return hostt->eh_abort_handler(scmd);
943 static void scsi_abort_eh_cmnd(struct scsi_cmnd *scmd)
945 if (scsi_try_to_abort_cmd(scmd->device->host->hostt, scmd) != SUCCESS)
946 if (scsi_try_bus_device_reset(scmd) != SUCCESS)
947 if (scsi_try_target_reset(scmd) != SUCCESS)
948 if (scsi_try_bus_reset(scmd) != SUCCESS)
949 scsi_try_host_reset(scmd);
953 * scsi_eh_prep_cmnd - Save a scsi command info as part of error recovery
954 * @scmd: SCSI command structure to hijack
955 * @ses: structure to save restore information
956 * @cmnd: CDB to send. Can be NULL if no new cmnd is needed
957 * @cmnd_size: size in bytes of @cmnd (must be <= BLK_MAX_CDB)
958 * @sense_bytes: size of sense data to copy. or 0 (if != 0 @cmnd is ignored)
960 * This function is used to save a scsi command information before re-execution
961 * as part of the error recovery process. If @sense_bytes is 0 the command
962 * sent must be one that does not transfer any data. If @sense_bytes != 0
963 * @cmnd is ignored and this functions sets up a REQUEST_SENSE command
964 * and cmnd buffers to read @sense_bytes into @scmd->sense_buffer.
966 void scsi_eh_prep_cmnd(struct scsi_cmnd *scmd, struct scsi_eh_save *ses,
967 unsigned char *cmnd, int cmnd_size, unsigned sense_bytes)
969 struct scsi_device *sdev = scmd->device;
972 * We need saved copies of a number of fields - this is because
973 * error handling may need to overwrite these with different values
974 * to run different commands, and once error handling is complete,
975 * we will need to restore these values prior to running the actual
978 ses->cmd_len = scmd->cmd_len;
979 ses->cmnd = scmd->cmnd;
980 ses->data_direction = scmd->sc_data_direction;
981 ses->sdb = scmd->sdb;
982 ses->result = scmd->result;
983 ses->resid_len = scmd->req.resid_len;
984 ses->underflow = scmd->underflow;
985 ses->prot_op = scmd->prot_op;
986 ses->eh_eflags = scmd->eh_eflags;
988 scmd->prot_op = SCSI_PROT_NORMAL;
990 scmd->cmnd = ses->eh_cmnd;
991 memset(scmd->cmnd, 0, BLK_MAX_CDB);
992 memset(&scmd->sdb, 0, sizeof(scmd->sdb));
994 scmd->req.resid_len = 0;
997 scmd->sdb.length = min_t(unsigned, SCSI_SENSE_BUFFERSIZE,
999 sg_init_one(&ses->sense_sgl, scmd->sense_buffer,
1001 scmd->sdb.table.sgl = &ses->sense_sgl;
1002 scmd->sc_data_direction = DMA_FROM_DEVICE;
1003 scmd->sdb.table.nents = scmd->sdb.table.orig_nents = 1;
1004 scmd->cmnd[0] = REQUEST_SENSE;
1005 scmd->cmnd[4] = scmd->sdb.length;
1006 scmd->cmd_len = COMMAND_SIZE(scmd->cmnd[0]);
1008 scmd->sc_data_direction = DMA_NONE;
1010 BUG_ON(cmnd_size > BLK_MAX_CDB);
1011 memcpy(scmd->cmnd, cmnd, cmnd_size);
1012 scmd->cmd_len = COMMAND_SIZE(scmd->cmnd[0]);
1016 scmd->underflow = 0;
1018 if (sdev->scsi_level <= SCSI_2 && sdev->scsi_level != SCSI_UNKNOWN)
1019 scmd->cmnd[1] = (scmd->cmnd[1] & 0x1f) |
1020 (sdev->lun << 5 & 0xe0);
1023 * Zero the sense buffer. The scsi spec mandates that any
1024 * untransferred sense data should be interpreted as being zero.
1026 memset(scmd->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE);
1028 EXPORT_SYMBOL(scsi_eh_prep_cmnd);
1031 * scsi_eh_restore_cmnd - Restore a scsi command info as part of error recovery
1032 * @scmd: SCSI command structure to restore
1033 * @ses: saved information from a coresponding call to scsi_eh_prep_cmnd
1035 * Undo any damage done by above scsi_eh_prep_cmnd().
1037 void scsi_eh_restore_cmnd(struct scsi_cmnd* scmd, struct scsi_eh_save *ses)
1040 * Restore original data
1042 scmd->cmd_len = ses->cmd_len;
1043 scmd->cmnd = ses->cmnd;
1044 scmd->sc_data_direction = ses->data_direction;
1045 scmd->sdb = ses->sdb;
1046 scmd->result = ses->result;
1047 scmd->req.resid_len = ses->resid_len;
1048 scmd->underflow = ses->underflow;
1049 scmd->prot_op = ses->prot_op;
1050 scmd->eh_eflags = ses->eh_eflags;
1052 EXPORT_SYMBOL(scsi_eh_restore_cmnd);
1055 * scsi_send_eh_cmnd - submit a scsi command as part of error recovery
1056 * @scmd: SCSI command structure to hijack
1057 * @cmnd: CDB to send
1058 * @cmnd_size: size in bytes of @cmnd
1059 * @timeout: timeout for this request
1060 * @sense_bytes: size of sense data to copy or 0
1062 * This function is used to send a scsi command down to a target device
1063 * as part of the error recovery process. See also scsi_eh_prep_cmnd() above.
1066 * SUCCESS or FAILED or NEEDS_RETRY
1068 static enum scsi_disposition scsi_send_eh_cmnd(struct scsi_cmnd *scmd,
1069 unsigned char *cmnd, int cmnd_size, int timeout, unsigned sense_bytes)
1071 struct scsi_device *sdev = scmd->device;
1072 struct Scsi_Host *shost = sdev->host;
1073 DECLARE_COMPLETION_ONSTACK(done);
1074 unsigned long timeleft = timeout, delay;
1075 struct scsi_eh_save ses;
1076 const unsigned long stall_for = msecs_to_jiffies(100);
1080 scsi_eh_prep_cmnd(scmd, &ses, cmnd, cmnd_size, sense_bytes);
1081 shost->eh_action = &done;
1083 scsi_log_send(scmd);
1084 scmd->submitter = SUBMITTED_BY_SCSI_ERROR_HANDLER;
1087 * Lock sdev->state_mutex to avoid that scsi_device_quiesce() can
1088 * change the SCSI device state after we have examined it and before
1089 * .queuecommand() is called.
1091 mutex_lock(&sdev->state_mutex);
1092 while (sdev->sdev_state == SDEV_BLOCK && timeleft > 0) {
1093 mutex_unlock(&sdev->state_mutex);
1094 SCSI_LOG_ERROR_RECOVERY(5, sdev_printk(KERN_DEBUG, sdev,
1095 "%s: state %d <> %d\n", __func__, sdev->sdev_state,
1097 delay = min(timeleft, stall_for);
1099 msleep(jiffies_to_msecs(delay));
1100 mutex_lock(&sdev->state_mutex);
1102 if (sdev->sdev_state != SDEV_BLOCK)
1103 rtn = shost->hostt->queuecommand(shost, scmd);
1106 mutex_unlock(&sdev->state_mutex);
1109 if (timeleft > stall_for) {
1110 scsi_eh_restore_cmnd(scmd, &ses);
1112 timeleft -= stall_for;
1113 msleep(jiffies_to_msecs(stall_for));
1116 /* signal not to enter either branch of the if () below */
1120 timeleft = wait_for_completion_timeout(&done, timeout);
1124 shost->eh_action = NULL;
1126 scsi_log_completion(scmd, rtn);
1128 SCSI_LOG_ERROR_RECOVERY(3, scmd_printk(KERN_INFO, scmd,
1129 "%s timeleft: %ld\n",
1130 __func__, timeleft));
1133 * If there is time left scsi_eh_done got called, and we will examine
1134 * the actual status codes to see whether the command actually did
1135 * complete normally, else if we have a zero return and no time left,
1136 * the command must still be pending, so abort it and return FAILED.
1137 * If we never actually managed to issue the command, because
1138 * ->queuecommand() kept returning non zero, use the rtn = FAILED
1139 * value above (so don't execute either branch of the if)
1142 rtn = scsi_eh_completed_normally(scmd);
1143 SCSI_LOG_ERROR_RECOVERY(3, scmd_printk(KERN_INFO, scmd,
1144 "%s: scsi_eh_completed_normally %x\n", __func__, rtn));
1151 case ADD_TO_MLQUEUE:
1158 } else if (rtn != FAILED) {
1159 scsi_abort_eh_cmnd(scmd);
1163 scsi_eh_restore_cmnd(scmd, &ses);
1169 * scsi_request_sense - Request sense data from a particular target.
1170 * @scmd: SCSI cmd for request sense.
1173 * Some hosts automatically obtain this information, others require
1174 * that we obtain it on our own. This function will *not* return until
1175 * the command either times out, or it completes.
1177 static enum scsi_disposition scsi_request_sense(struct scsi_cmnd *scmd)
1179 return scsi_send_eh_cmnd(scmd, NULL, 0, scmd->device->eh_timeout, ~0);
1182 static enum scsi_disposition
1183 scsi_eh_action(struct scsi_cmnd *scmd, enum scsi_disposition rtn)
1185 if (!blk_rq_is_passthrough(scsi_cmd_to_rq(scmd))) {
1186 struct scsi_driver *sdrv = scsi_cmd_to_driver(scmd);
1187 if (sdrv->eh_action)
1188 rtn = sdrv->eh_action(scmd, rtn);
1194 * scsi_eh_finish_cmd - Handle a cmd that eh is finished with.
1195 * @scmd: Original SCSI cmd that eh has finished.
1196 * @done_q: Queue for processed commands.
1199 * We don't want to use the normal command completion while we are are
1200 * still handling errors - it may cause other commands to be queued,
1201 * and that would disturb what we are doing. Thus we really want to
1202 * keep a list of pending commands for final completion, and once we
1203 * are ready to leave error handling we handle completion for real.
1205 void scsi_eh_finish_cmd(struct scsi_cmnd *scmd, struct list_head *done_q)
1207 list_move_tail(&scmd->eh_entry, done_q);
1209 EXPORT_SYMBOL(scsi_eh_finish_cmd);
1212 * scsi_eh_get_sense - Get device sense data.
1213 * @work_q: Queue of commands to process.
1214 * @done_q: Queue of processed commands.
1217 * See if we need to request sense information. if so, then get it
1218 * now, so we have a better idea of what to do.
1221 * This has the unfortunate side effect that if a shost adapter does
1222 * not automatically request sense information, we end up shutting
1223 * it down before we request it.
1225 * All drivers should request sense information internally these days,
1226 * so for now all I have to say is tough noogies if you end up in here.
1228 * XXX: Long term this code should go away, but that needs an audit of
1231 int scsi_eh_get_sense(struct list_head *work_q,
1232 struct list_head *done_q)
1234 struct scsi_cmnd *scmd, *next;
1235 struct Scsi_Host *shost;
1236 enum scsi_disposition rtn;
1239 * If SCSI_EH_ABORT_SCHEDULED has been set, it is timeout IO,
1240 * should not get sense.
1242 list_for_each_entry_safe(scmd, next, work_q, eh_entry) {
1243 if ((scmd->eh_eflags & SCSI_EH_ABORT_SCHEDULED) ||
1244 SCSI_SENSE_VALID(scmd))
1247 shost = scmd->device->host;
1248 if (scsi_host_eh_past_deadline(shost)) {
1249 SCSI_LOG_ERROR_RECOVERY(3,
1250 scmd_printk(KERN_INFO, scmd,
1251 "%s: skip request sense, past eh deadline\n",
1255 if (!scsi_status_is_check_condition(scmd->result))
1257 * don't request sense if there's no check condition
1258 * status because the error we're processing isn't one
1259 * that has a sense code (and some devices get
1260 * confused by sense requests out of the blue)
1264 SCSI_LOG_ERROR_RECOVERY(2, scmd_printk(KERN_INFO, scmd,
1265 "%s: requesting sense\n",
1267 rtn = scsi_request_sense(scmd);
1271 SCSI_LOG_ERROR_RECOVERY(3, scmd_printk(KERN_INFO, scmd,
1272 "sense requested, result %x\n", scmd->result));
1273 SCSI_LOG_ERROR_RECOVERY(3, scsi_print_sense(scmd));
1275 rtn = scsi_decide_disposition(scmd);
1278 * if the result was normal, then just pass it along to the
1283 * We don't want this command reissued, just finished
1284 * with the sense data, so set retries to the max
1285 * allowed to ensure it won't get reissued. If the user
1286 * has requested infinite retries, we also want to
1287 * finish this command, so force completion by setting
1288 * retries and allowed to the same value.
1290 if (scmd->allowed == SCSI_CMD_RETRIES_NO_LIMIT)
1291 scmd->retries = scmd->allowed = 1;
1293 scmd->retries = scmd->allowed;
1294 else if (rtn != NEEDS_RETRY)
1297 scsi_eh_finish_cmd(scmd, done_q);
1300 return list_empty(work_q);
1302 EXPORT_SYMBOL_GPL(scsi_eh_get_sense);
1305 * scsi_eh_tur - Send TUR to device.
1306 * @scmd: &scsi_cmnd to send TUR
1309 * 0 - Device is ready. 1 - Device NOT ready.
1311 static int scsi_eh_tur(struct scsi_cmnd *scmd)
1313 static unsigned char tur_command[6] = {TEST_UNIT_READY, 0, 0, 0, 0, 0};
1315 enum scsi_disposition rtn;
1318 rtn = scsi_send_eh_cmnd(scmd, tur_command, 6,
1319 scmd->device->eh_timeout, 0);
1321 SCSI_LOG_ERROR_RECOVERY(3, scmd_printk(KERN_INFO, scmd,
1322 "%s return: %x\n", __func__, rtn));
1337 * scsi_eh_test_devices - check if devices are responding from error recovery.
1338 * @cmd_list: scsi commands in error recovery.
1339 * @work_q: queue for commands which still need more error recovery
1340 * @done_q: queue for commands which are finished
1341 * @try_stu: boolean on if a STU command should be tried in addition to TUR.
1344 * Tests if devices are in a working state. Commands to devices now in
1345 * a working state are sent to the done_q while commands to devices which
1346 * are still failing to respond are returned to the work_q for more
1349 static int scsi_eh_test_devices(struct list_head *cmd_list,
1350 struct list_head *work_q,
1351 struct list_head *done_q, int try_stu)
1353 struct scsi_cmnd *scmd, *next;
1354 struct scsi_device *sdev;
1357 while (!list_empty(cmd_list)) {
1358 scmd = list_entry(cmd_list->next, struct scsi_cmnd, eh_entry);
1359 sdev = scmd->device;
1362 if (scsi_host_eh_past_deadline(sdev->host)) {
1363 /* Push items back onto work_q */
1364 list_splice_init(cmd_list, work_q);
1365 SCSI_LOG_ERROR_RECOVERY(3,
1366 sdev_printk(KERN_INFO, sdev,
1367 "%s: skip test device, past eh deadline",
1373 finish_cmds = !scsi_device_online(scmd->device) ||
1374 (try_stu && !scsi_eh_try_stu(scmd) &&
1375 !scsi_eh_tur(scmd)) ||
1378 list_for_each_entry_safe(scmd, next, cmd_list, eh_entry)
1379 if (scmd->device == sdev) {
1382 scsi_eh_action(scmd, SUCCESS) == SUCCESS))
1383 scsi_eh_finish_cmd(scmd, done_q);
1385 list_move_tail(&scmd->eh_entry, work_q);
1388 return list_empty(work_q);
1392 * scsi_eh_try_stu - Send START_UNIT to device.
1393 * @scmd: &scsi_cmnd to send START_UNIT
1396 * 0 - Device is ready. 1 - Device NOT ready.
1398 static int scsi_eh_try_stu(struct scsi_cmnd *scmd)
1400 static unsigned char stu_command[6] = {START_STOP, 0, 0, 0, 1, 0};
1402 if (scmd->device->allow_restart) {
1404 enum scsi_disposition rtn = NEEDS_RETRY;
1406 for (i = 0; rtn == NEEDS_RETRY && i < 2; i++)
1407 rtn = scsi_send_eh_cmnd(scmd, stu_command, 6, scmd->device->request_queue->rq_timeout, 0);
1417 * scsi_eh_stu - send START_UNIT if needed
1418 * @shost: &scsi host being recovered.
1419 * @work_q: &list_head for pending commands.
1420 * @done_q: &list_head for processed commands.
1423 * If commands are failing due to not ready, initializing command required,
1424 * try revalidating the device, which will end up sending a start unit.
1426 static int scsi_eh_stu(struct Scsi_Host *shost,
1427 struct list_head *work_q,
1428 struct list_head *done_q)
1430 struct scsi_cmnd *scmd, *stu_scmd, *next;
1431 struct scsi_device *sdev;
1433 shost_for_each_device(sdev, shost) {
1434 if (scsi_host_eh_past_deadline(shost)) {
1435 SCSI_LOG_ERROR_RECOVERY(3,
1436 sdev_printk(KERN_INFO, sdev,
1437 "%s: skip START_UNIT, past eh deadline\n",
1439 scsi_device_put(sdev);
1443 list_for_each_entry(scmd, work_q, eh_entry)
1444 if (scmd->device == sdev && SCSI_SENSE_VALID(scmd) &&
1445 scsi_check_sense(scmd) == FAILED ) {
1453 SCSI_LOG_ERROR_RECOVERY(3,
1454 sdev_printk(KERN_INFO, sdev,
1455 "%s: Sending START_UNIT\n",
1458 if (!scsi_eh_try_stu(stu_scmd)) {
1459 if (!scsi_device_online(sdev) ||
1460 !scsi_eh_tur(stu_scmd)) {
1461 list_for_each_entry_safe(scmd, next,
1463 if (scmd->device == sdev &&
1464 scsi_eh_action(scmd, SUCCESS) == SUCCESS)
1465 scsi_eh_finish_cmd(scmd, done_q);
1469 SCSI_LOG_ERROR_RECOVERY(3,
1470 sdev_printk(KERN_INFO, sdev,
1471 "%s: START_UNIT failed\n",
1476 return list_empty(work_q);
1481 * scsi_eh_bus_device_reset - send bdr if needed
1482 * @shost: scsi host being recovered.
1483 * @work_q: &list_head for pending commands.
1484 * @done_q: &list_head for processed commands.
1487 * Try a bus device reset. Still, look to see whether we have multiple
1488 * devices that are jammed or not - if we have multiple devices, it
1489 * makes no sense to try bus_device_reset - we really would need to try
1490 * a bus_reset instead.
1492 static int scsi_eh_bus_device_reset(struct Scsi_Host *shost,
1493 struct list_head *work_q,
1494 struct list_head *done_q)
1496 struct scsi_cmnd *scmd, *bdr_scmd, *next;
1497 struct scsi_device *sdev;
1498 enum scsi_disposition rtn;
1500 shost_for_each_device(sdev, shost) {
1501 if (scsi_host_eh_past_deadline(shost)) {
1502 SCSI_LOG_ERROR_RECOVERY(3,
1503 sdev_printk(KERN_INFO, sdev,
1504 "%s: skip BDR, past eh deadline\n",
1506 scsi_device_put(sdev);
1510 list_for_each_entry(scmd, work_q, eh_entry)
1511 if (scmd->device == sdev) {
1519 SCSI_LOG_ERROR_RECOVERY(3,
1520 sdev_printk(KERN_INFO, sdev,
1521 "%s: Sending BDR\n", current->comm));
1522 rtn = scsi_try_bus_device_reset(bdr_scmd);
1523 if (rtn == SUCCESS || rtn == FAST_IO_FAIL) {
1524 if (!scsi_device_online(sdev) ||
1525 rtn == FAST_IO_FAIL ||
1526 !scsi_eh_tur(bdr_scmd)) {
1527 list_for_each_entry_safe(scmd, next,
1529 if (scmd->device == sdev &&
1530 scsi_eh_action(scmd, rtn) != FAILED)
1531 scsi_eh_finish_cmd(scmd,
1536 SCSI_LOG_ERROR_RECOVERY(3,
1537 sdev_printk(KERN_INFO, sdev,
1538 "%s: BDR failed\n", current->comm));
1542 return list_empty(work_q);
1546 * scsi_eh_target_reset - send target reset if needed
1547 * @shost: scsi host being recovered.
1548 * @work_q: &list_head for pending commands.
1549 * @done_q: &list_head for processed commands.
1552 * Try a target reset.
1554 static int scsi_eh_target_reset(struct Scsi_Host *shost,
1555 struct list_head *work_q,
1556 struct list_head *done_q)
1558 LIST_HEAD(tmp_list);
1559 LIST_HEAD(check_list);
1561 list_splice_init(work_q, &tmp_list);
1563 while (!list_empty(&tmp_list)) {
1564 struct scsi_cmnd *next, *scmd;
1565 enum scsi_disposition rtn;
1568 if (scsi_host_eh_past_deadline(shost)) {
1569 /* push back on work queue for further processing */
1570 list_splice_init(&check_list, work_q);
1571 list_splice_init(&tmp_list, work_q);
1572 SCSI_LOG_ERROR_RECOVERY(3,
1573 shost_printk(KERN_INFO, shost,
1574 "%s: Skip target reset, past eh deadline\n",
1576 return list_empty(work_q);
1579 scmd = list_entry(tmp_list.next, struct scsi_cmnd, eh_entry);
1582 SCSI_LOG_ERROR_RECOVERY(3,
1583 shost_printk(KERN_INFO, shost,
1584 "%s: Sending target reset to target %d\n",
1585 current->comm, id));
1586 rtn = scsi_try_target_reset(scmd);
1587 if (rtn != SUCCESS && rtn != FAST_IO_FAIL)
1588 SCSI_LOG_ERROR_RECOVERY(3,
1589 shost_printk(KERN_INFO, shost,
1590 "%s: Target reset failed"
1592 current->comm, id));
1593 list_for_each_entry_safe(scmd, next, &tmp_list, eh_entry) {
1594 if (scmd_id(scmd) != id)
1598 list_move_tail(&scmd->eh_entry, &check_list);
1599 else if (rtn == FAST_IO_FAIL)
1600 scsi_eh_finish_cmd(scmd, done_q);
1602 /* push back on work queue for further processing */
1603 list_move(&scmd->eh_entry, work_q);
1607 return scsi_eh_test_devices(&check_list, work_q, done_q, 0);
1611 * scsi_eh_bus_reset - send a bus reset
1612 * @shost: &scsi host being recovered.
1613 * @work_q: &list_head for pending commands.
1614 * @done_q: &list_head for processed commands.
1616 static int scsi_eh_bus_reset(struct Scsi_Host *shost,
1617 struct list_head *work_q,
1618 struct list_head *done_q)
1620 struct scsi_cmnd *scmd, *chan_scmd, *next;
1621 LIST_HEAD(check_list);
1622 unsigned int channel;
1623 enum scsi_disposition rtn;
1626 * we really want to loop over the various channels, and do this on
1627 * a channel by channel basis. we should also check to see if any
1628 * of the failed commands are on soft_reset devices, and if so, skip
1632 for (channel = 0; channel <= shost->max_channel; channel++) {
1633 if (scsi_host_eh_past_deadline(shost)) {
1634 list_splice_init(&check_list, work_q);
1635 SCSI_LOG_ERROR_RECOVERY(3,
1636 shost_printk(KERN_INFO, shost,
1637 "%s: skip BRST, past eh deadline\n",
1639 return list_empty(work_q);
1643 list_for_each_entry(scmd, work_q, eh_entry) {
1644 if (channel == scmd_channel(scmd)) {
1648 * FIXME add back in some support for
1649 * soft_reset devices.
1656 SCSI_LOG_ERROR_RECOVERY(3,
1657 shost_printk(KERN_INFO, shost,
1658 "%s: Sending BRST chan: %d\n",
1659 current->comm, channel));
1660 rtn = scsi_try_bus_reset(chan_scmd);
1661 if (rtn == SUCCESS || rtn == FAST_IO_FAIL) {
1662 list_for_each_entry_safe(scmd, next, work_q, eh_entry) {
1663 if (channel == scmd_channel(scmd)) {
1664 if (rtn == FAST_IO_FAIL)
1665 scsi_eh_finish_cmd(scmd,
1668 list_move_tail(&scmd->eh_entry,
1673 SCSI_LOG_ERROR_RECOVERY(3,
1674 shost_printk(KERN_INFO, shost,
1675 "%s: BRST failed chan: %d\n",
1676 current->comm, channel));
1679 return scsi_eh_test_devices(&check_list, work_q, done_q, 0);
1683 * scsi_eh_host_reset - send a host reset
1684 * @shost: host to be reset.
1685 * @work_q: &list_head for pending commands.
1686 * @done_q: &list_head for processed commands.
1688 static int scsi_eh_host_reset(struct Scsi_Host *shost,
1689 struct list_head *work_q,
1690 struct list_head *done_q)
1692 struct scsi_cmnd *scmd, *next;
1693 LIST_HEAD(check_list);
1694 enum scsi_disposition rtn;
1696 if (!list_empty(work_q)) {
1697 scmd = list_entry(work_q->next,
1698 struct scsi_cmnd, eh_entry);
1700 SCSI_LOG_ERROR_RECOVERY(3,
1701 shost_printk(KERN_INFO, shost,
1702 "%s: Sending HRST\n",
1705 rtn = scsi_try_host_reset(scmd);
1706 if (rtn == SUCCESS) {
1707 list_splice_init(work_q, &check_list);
1708 } else if (rtn == FAST_IO_FAIL) {
1709 list_for_each_entry_safe(scmd, next, work_q, eh_entry) {
1710 scsi_eh_finish_cmd(scmd, done_q);
1713 SCSI_LOG_ERROR_RECOVERY(3,
1714 shost_printk(KERN_INFO, shost,
1715 "%s: HRST failed\n",
1719 return scsi_eh_test_devices(&check_list, work_q, done_q, 1);
1723 * scsi_eh_offline_sdevs - offline scsi devices that fail to recover
1724 * @work_q: &list_head for pending commands.
1725 * @done_q: &list_head for processed commands.
1727 static void scsi_eh_offline_sdevs(struct list_head *work_q,
1728 struct list_head *done_q)
1730 struct scsi_cmnd *scmd, *next;
1731 struct scsi_device *sdev;
1733 list_for_each_entry_safe(scmd, next, work_q, eh_entry) {
1734 sdev_printk(KERN_INFO, scmd->device, "Device offlined - "
1735 "not ready after error recovery\n");
1736 sdev = scmd->device;
1738 mutex_lock(&sdev->state_mutex);
1739 scsi_device_set_state(sdev, SDEV_OFFLINE);
1740 mutex_unlock(&sdev->state_mutex);
1742 scsi_eh_finish_cmd(scmd, done_q);
1748 * scsi_noretry_cmd - determine if command should be failed fast
1749 * @scmd: SCSI cmd to examine.
1751 int scsi_noretry_cmd(struct scsi_cmnd *scmd)
1753 struct request *req = scsi_cmd_to_rq(scmd);
1755 switch (host_byte(scmd->result)) {
1761 return req->cmd_flags & REQ_FAILFAST_TRANSPORT;
1763 return req->cmd_flags & REQ_FAILFAST_DEV;
1765 if (get_status_byte(scmd) == SAM_STAT_RESERVATION_CONFLICT)
1768 case DID_SOFT_ERROR:
1769 return req->cmd_flags & REQ_FAILFAST_DRIVER;
1772 if (!scsi_status_is_check_condition(scmd->result))
1777 * assume caller has checked sense and determined
1778 * the check condition was retryable.
1780 if (req->cmd_flags & REQ_FAILFAST_DEV || blk_rq_is_passthrough(req))
1787 * scsi_decide_disposition - Disposition a cmd on return from LLD.
1788 * @scmd: SCSI cmd to examine.
1791 * This is *only* called when we are examining the status after sending
1792 * out the actual data command. any commands that are queued for error
1793 * recovery (e.g. test_unit_ready) do *not* come through here.
1795 * When this routine returns failed, it means the error handler thread
1796 * is woken. In cases where the error code indicates an error that
1797 * doesn't require the error handler read (i.e. we don't need to
1798 * abort/reset), this function should return SUCCESS.
1800 enum scsi_disposition scsi_decide_disposition(struct scsi_cmnd *scmd)
1802 enum scsi_disposition rtn;
1805 * if the device is offline, then we clearly just pass the result back
1806 * up to the top level.
1808 if (!scsi_device_online(scmd->device)) {
1809 SCSI_LOG_ERROR_RECOVERY(5, scmd_printk(KERN_INFO, scmd,
1810 "%s: device offline - report as SUCCESS\n", __func__));
1815 * first check the host byte, to see if there is anything in there
1816 * that would indicate what we need to do.
1818 switch (host_byte(scmd->result)) {
1819 case DID_PASSTHROUGH:
1821 * no matter what, pass this through to the upper layer.
1822 * nuke this special code so that it looks like we are saying
1825 scmd->result &= 0xff00ffff;
1829 * looks good. drop through, and check the next byte.
1833 if (scmd->eh_eflags & SCSI_EH_ABORT_SCHEDULED) {
1834 set_host_byte(scmd, DID_TIME_OUT);
1838 case DID_NO_CONNECT:
1839 case DID_BAD_TARGET:
1841 * note - this means that we just report the status back
1842 * to the top level driver, not that we actually think
1843 * that it indicates SUCCESS.
1846 case DID_SOFT_ERROR:
1848 * when the low level driver returns did_soft_error,
1849 * it is responsible for keeping an internal retry counter
1850 * in order to avoid endless loops (db)
1857 return ADD_TO_MLQUEUE;
1858 case DID_TRANSPORT_DISRUPTED:
1860 * LLD/transport was disrupted during processing of the IO.
1861 * The transport class is now blocked/blocking,
1862 * and the transport will decide what to do with the IO
1863 * based on its timers and recovery capablilities if
1864 * there are enough retries.
1867 case DID_TRANSPORT_FAILFAST:
1869 * The transport decided to failfast the IO (most likely
1870 * the fast io fail tmo fired), so send IO directly upwards.
1873 case DID_TRANSPORT_MARGINAL:
1875 * caller has decided not to do retries on
1876 * abort success, so send IO directly upwards
1880 if (get_status_byte(scmd) == SAM_STAT_RESERVATION_CONFLICT)
1882 * execute reservation conflict processing code
1892 * when we scan the bus, we get timeout messages for
1893 * these commands if there is no device available.
1894 * other hosts report did_no_connect for the same thing.
1896 if ((scmd->cmnd[0] == TEST_UNIT_READY ||
1897 scmd->cmnd[0] == INQUIRY)) {
1909 * check the status byte to see if this indicates anything special.
1911 switch (get_status_byte(scmd)) {
1912 case SAM_STAT_TASK_SET_FULL:
1913 scsi_handle_queue_full(scmd->device);
1915 * the case of trying to send too many commands to a
1916 * tagged queueing device.
1921 * device can't talk to us at the moment. Should only
1922 * occur (SAM-3) when the task queue is empty, so will cause
1923 * the empty queue handling to trigger a stall in the
1926 return ADD_TO_MLQUEUE;
1928 if (scmd->cmnd[0] == REPORT_LUNS)
1929 scmd->device->sdev_target->expecting_lun_change = 0;
1930 scsi_handle_queue_ramp_up(scmd->device);
1932 case SAM_STAT_COMMAND_TERMINATED:
1934 case SAM_STAT_TASK_ABORTED:
1936 case SAM_STAT_CHECK_CONDITION:
1937 rtn = scsi_check_sense(scmd);
1938 if (rtn == NEEDS_RETRY)
1940 /* if rtn == FAILED, we have no sense information;
1941 * returning FAILED will wake the error handler thread
1942 * to collect the sense and redo the decide
1945 case SAM_STAT_CONDITION_MET:
1946 case SAM_STAT_INTERMEDIATE:
1947 case SAM_STAT_INTERMEDIATE_CONDITION_MET:
1948 case SAM_STAT_ACA_ACTIVE:
1950 * who knows? FIXME(eric)
1954 case SAM_STAT_RESERVATION_CONFLICT:
1955 sdev_printk(KERN_INFO, scmd->device,
1956 "reservation conflict\n");
1957 set_host_byte(scmd, DID_NEXUS_FAILURE);
1958 return SUCCESS; /* causes immediate i/o error */
1966 /* we requeue for retry because the error was retryable, and
1967 * the request was not marked fast fail. Note that above,
1968 * even if the request is marked fast fail, we still requeue
1969 * for queue congestion conditions (QUEUE_FULL or BUSY) */
1970 if (scsi_cmd_retry_allowed(scmd) && !scsi_noretry_cmd(scmd)) {
1974 * no more retries - report this one back to upper level.
1980 static void eh_lock_door_done(struct request *req, blk_status_t status)
1982 blk_mq_free_request(req);
1986 * scsi_eh_lock_door - Prevent medium removal for the specified device
1987 * @sdev: SCSI device to prevent medium removal
1990 * We must be called from process context.
1993 * We queue up an asynchronous "ALLOW MEDIUM REMOVAL" request on the
1994 * head of the devices request queue, and continue.
1996 static void scsi_eh_lock_door(struct scsi_device *sdev)
1998 struct request *req;
1999 struct scsi_request *rq;
2001 req = scsi_alloc_request(sdev->request_queue, REQ_OP_DRV_IN, 0);
2006 rq->cmd[0] = ALLOW_MEDIUM_REMOVAL;
2010 rq->cmd[4] = SCSI_REMOVAL_PREVENT;
2012 rq->cmd_len = COMMAND_SIZE(rq->cmd[0]);
2014 req->rq_flags |= RQF_QUIET;
2015 req->timeout = 10 * HZ;
2018 blk_execute_rq_nowait(NULL, req, 1, eh_lock_door_done);
2022 * scsi_restart_operations - restart io operations to the specified host.
2023 * @shost: Host we are restarting.
2026 * When we entered the error handler, we blocked all further i/o to
2027 * this device. we need to 'reverse' this process.
2029 static void scsi_restart_operations(struct Scsi_Host *shost)
2031 struct scsi_device *sdev;
2032 unsigned long flags;
2035 * If the door was locked, we need to insert a door lock request
2036 * onto the head of the SCSI request queue for the device. There
2037 * is no point trying to lock the door of an off-line device.
2039 shost_for_each_device(sdev, shost) {
2040 if (scsi_device_online(sdev) && sdev->was_reset && sdev->locked) {
2041 scsi_eh_lock_door(sdev);
2042 sdev->was_reset = 0;
2047 * next free up anything directly waiting upon the host. this
2048 * will be requests for character device operations, and also for
2049 * ioctls to queued block devices.
2051 SCSI_LOG_ERROR_RECOVERY(3,
2052 shost_printk(KERN_INFO, shost, "waking up host to restart\n"));
2054 spin_lock_irqsave(shost->host_lock, flags);
2055 if (scsi_host_set_state(shost, SHOST_RUNNING))
2056 if (scsi_host_set_state(shost, SHOST_CANCEL))
2057 BUG_ON(scsi_host_set_state(shost, SHOST_DEL));
2058 spin_unlock_irqrestore(shost->host_lock, flags);
2060 wake_up(&shost->host_wait);
2063 * finally we need to re-initiate requests that may be pending. we will
2064 * have had everything blocked while error handling is taking place, and
2065 * now that error recovery is done, we will need to ensure that these
2066 * requests are started.
2068 scsi_run_host_queues(shost);
2071 * if eh is active and host_eh_scheduled is pending we need to re-run
2072 * recovery. we do this check after scsi_run_host_queues() to allow
2073 * everything pent up since the last eh run a chance to make forward
2074 * progress before we sync again. Either we'll immediately re-run
2075 * recovery or scsi_device_unbusy() will wake us again when these
2076 * pending commands complete.
2078 spin_lock_irqsave(shost->host_lock, flags);
2079 if (shost->host_eh_scheduled)
2080 if (scsi_host_set_state(shost, SHOST_RECOVERY))
2081 WARN_ON(scsi_host_set_state(shost, SHOST_CANCEL_RECOVERY));
2082 spin_unlock_irqrestore(shost->host_lock, flags);
2086 * scsi_eh_ready_devs - check device ready state and recover if not.
2087 * @shost: host to be recovered.
2088 * @work_q: &list_head for pending commands.
2089 * @done_q: &list_head for processed commands.
2091 void scsi_eh_ready_devs(struct Scsi_Host *shost,
2092 struct list_head *work_q,
2093 struct list_head *done_q)
2095 if (!scsi_eh_stu(shost, work_q, done_q))
2096 if (!scsi_eh_bus_device_reset(shost, work_q, done_q))
2097 if (!scsi_eh_target_reset(shost, work_q, done_q))
2098 if (!scsi_eh_bus_reset(shost, work_q, done_q))
2099 if (!scsi_eh_host_reset(shost, work_q, done_q))
2100 scsi_eh_offline_sdevs(work_q,
2103 EXPORT_SYMBOL_GPL(scsi_eh_ready_devs);
2106 * scsi_eh_flush_done_q - finish processed commands or retry them.
2107 * @done_q: list_head of processed commands.
2109 void scsi_eh_flush_done_q(struct list_head *done_q)
2111 struct scsi_cmnd *scmd, *next;
2113 list_for_each_entry_safe(scmd, next, done_q, eh_entry) {
2114 list_del_init(&scmd->eh_entry);
2115 if (scsi_device_online(scmd->device) &&
2116 !scsi_noretry_cmd(scmd) && scsi_cmd_retry_allowed(scmd) &&
2117 scsi_eh_should_retry_cmd(scmd)) {
2118 SCSI_LOG_ERROR_RECOVERY(3,
2119 scmd_printk(KERN_INFO, scmd,
2120 "%s: flush retry cmd\n",
2122 scsi_queue_insert(scmd, SCSI_MLQUEUE_EH_RETRY);
2125 * If just we got sense for the device (called
2126 * scsi_eh_get_sense), scmd->result is already
2127 * set, do not set DID_TIME_OUT.
2130 scmd->result |= (DID_TIME_OUT << 16);
2131 SCSI_LOG_ERROR_RECOVERY(3,
2132 scmd_printk(KERN_INFO, scmd,
2133 "%s: flush finish cmd\n",
2135 scsi_finish_command(scmd);
2139 EXPORT_SYMBOL(scsi_eh_flush_done_q);
2142 * scsi_unjam_host - Attempt to fix a host which has a cmd that failed.
2143 * @shost: Host to unjam.
2146 * When we come in here, we *know* that all commands on the bus have
2147 * either completed, failed or timed out. we also know that no further
2148 * commands are being sent to the host, so things are relatively quiet
2149 * and we have freedom to fiddle with things as we wish.
2151 * This is only the *default* implementation. it is possible for
2152 * individual drivers to supply their own version of this function, and
2153 * if the maintainer wishes to do this, it is strongly suggested that
2154 * this function be taken as a template and modified. this function
2155 * was designed to correctly handle problems for about 95% of the
2156 * different cases out there, and it should always provide at least a
2157 * reasonable amount of error recovery.
2159 * Any command marked 'failed' or 'timeout' must eventually have
2160 * scsi_finish_cmd() called for it. we do all of the retry stuff
2161 * here, so when we restart the host after we return it should have an
2164 static void scsi_unjam_host(struct Scsi_Host *shost)
2166 unsigned long flags;
2167 LIST_HEAD(eh_work_q);
2168 LIST_HEAD(eh_done_q);
2170 spin_lock_irqsave(shost->host_lock, flags);
2171 list_splice_init(&shost->eh_cmd_q, &eh_work_q);
2172 spin_unlock_irqrestore(shost->host_lock, flags);
2174 SCSI_LOG_ERROR_RECOVERY(1, scsi_eh_prt_fail_stats(shost, &eh_work_q));
2176 if (!scsi_eh_get_sense(&eh_work_q, &eh_done_q))
2177 scsi_eh_ready_devs(shost, &eh_work_q, &eh_done_q);
2179 spin_lock_irqsave(shost->host_lock, flags);
2180 if (shost->eh_deadline != -1)
2181 shost->last_reset = 0;
2182 spin_unlock_irqrestore(shost->host_lock, flags);
2183 scsi_eh_flush_done_q(&eh_done_q);
2187 * scsi_error_handler - SCSI error handler thread
2188 * @data: Host for which we are running.
2191 * This is the main error handling loop. This is run as a kernel thread
2192 * for every SCSI host and handles all error handling activity.
2194 int scsi_error_handler(void *data)
2196 struct Scsi_Host *shost = data;
2199 * We use TASK_INTERRUPTIBLE so that the thread is not
2200 * counted against the load average as a running process.
2201 * We never actually get interrupted because kthread_run
2202 * disables signal delivery for the created thread.
2206 * The sequence in kthread_stop() sets the stop flag first
2207 * then wakes the process. To avoid missed wakeups, the task
2208 * should always be in a non running state before the stop
2211 set_current_state(TASK_INTERRUPTIBLE);
2212 if (kthread_should_stop())
2215 if ((shost->host_failed == 0 && shost->host_eh_scheduled == 0) ||
2216 shost->host_failed != scsi_host_busy(shost)) {
2217 SCSI_LOG_ERROR_RECOVERY(1,
2218 shost_printk(KERN_INFO, shost,
2219 "scsi_eh_%d: sleeping\n",
2225 __set_current_state(TASK_RUNNING);
2226 SCSI_LOG_ERROR_RECOVERY(1,
2227 shost_printk(KERN_INFO, shost,
2228 "scsi_eh_%d: waking up %d/%d/%d\n",
2229 shost->host_no, shost->host_eh_scheduled,
2231 scsi_host_busy(shost)));
2234 * We have a host that is failing for some reason. Figure out
2235 * what we need to do to get it up and online again (if we can).
2236 * If we fail, we end up taking the thing offline.
2238 if (!shost->eh_noresume && scsi_autopm_get_host(shost) != 0) {
2239 SCSI_LOG_ERROR_RECOVERY(1,
2240 shost_printk(KERN_ERR, shost,
2241 "scsi_eh_%d: unable to autoresume\n",
2246 if (shost->transportt->eh_strategy_handler)
2247 shost->transportt->eh_strategy_handler(shost);
2249 scsi_unjam_host(shost);
2251 /* All scmds have been handled */
2252 shost->host_failed = 0;
2255 * Note - if the above fails completely, the action is to take
2256 * individual devices offline and flush the queue of any
2257 * outstanding requests that may have been pending. When we
2258 * restart, we restart any I/O to any other devices on the bus
2259 * which are still online.
2261 scsi_restart_operations(shost);
2262 if (!shost->eh_noresume)
2263 scsi_autopm_put_host(shost);
2265 __set_current_state(TASK_RUNNING);
2267 SCSI_LOG_ERROR_RECOVERY(1,
2268 shost_printk(KERN_INFO, shost,
2269 "Error handler scsi_eh_%d exiting\n",
2271 shost->ehandler = NULL;
2276 * Function: scsi_report_bus_reset()
2278 * Purpose: Utility function used by low-level drivers to report that
2279 * they have observed a bus reset on the bus being handled.
2281 * Arguments: shost - Host in question
2282 * channel - channel on which reset was observed.
2286 * Lock status: Host lock must be held.
2288 * Notes: This only needs to be called if the reset is one which
2289 * originates from an unknown location. Resets originated
2290 * by the mid-level itself don't need to call this, but there
2291 * should be no harm.
2293 * The main purpose of this is to make sure that a CHECK_CONDITION
2294 * is properly treated.
2296 void scsi_report_bus_reset(struct Scsi_Host *shost, int channel)
2298 struct scsi_device *sdev;
2300 __shost_for_each_device(sdev, shost) {
2301 if (channel == sdev_channel(sdev))
2302 __scsi_report_device_reset(sdev, NULL);
2305 EXPORT_SYMBOL(scsi_report_bus_reset);
2308 * Function: scsi_report_device_reset()
2310 * Purpose: Utility function used by low-level drivers to report that
2311 * they have observed a device reset on the device being handled.
2313 * Arguments: shost - Host in question
2314 * channel - channel on which reset was observed
2315 * target - target on which reset was observed
2319 * Lock status: Host lock must be held
2321 * Notes: This only needs to be called if the reset is one which
2322 * originates from an unknown location. Resets originated
2323 * by the mid-level itself don't need to call this, but there
2324 * should be no harm.
2326 * The main purpose of this is to make sure that a CHECK_CONDITION
2327 * is properly treated.
2329 void scsi_report_device_reset(struct Scsi_Host *shost, int channel, int target)
2331 struct scsi_device *sdev;
2333 __shost_for_each_device(sdev, shost) {
2334 if (channel == sdev_channel(sdev) &&
2335 target == sdev_id(sdev))
2336 __scsi_report_device_reset(sdev, NULL);
2339 EXPORT_SYMBOL(scsi_report_device_reset);
2342 * scsi_ioctl_reset: explicitly reset a host/bus/target/device
2343 * @dev: scsi_device to operate on
2344 * @arg: reset type (see sg.h)
2347 scsi_ioctl_reset(struct scsi_device *dev, int __user *arg)
2349 struct scsi_cmnd *scmd;
2350 struct Scsi_Host *shost = dev->host;
2352 unsigned long flags;
2354 enum scsi_disposition rtn;
2356 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2359 error = get_user(val, arg);
2363 if (scsi_autopm_get_host(shost) < 0)
2367 rq = kzalloc(sizeof(struct request) + sizeof(struct scsi_cmnd) +
2368 shost->hostt->cmd_size, GFP_KERNEL);
2370 goto out_put_autopm_host;
2371 blk_rq_init(NULL, rq);
2373 scmd = (struct scsi_cmnd *)(rq + 1);
2374 scsi_init_command(dev, scmd);
2375 scmd->cmnd = scsi_req(rq)->cmd;
2377 scmd->submitter = SUBMITTED_BY_SCSI_RESET_IOCTL;
2378 memset(&scmd->sdb, 0, sizeof(scmd->sdb));
2382 scmd->sc_data_direction = DMA_BIDIRECTIONAL;
2384 spin_lock_irqsave(shost->host_lock, flags);
2385 shost->tmf_in_progress = 1;
2386 spin_unlock_irqrestore(shost->host_lock, flags);
2388 switch (val & ~SG_SCSI_RESET_NO_ESCALATE) {
2389 case SG_SCSI_RESET_NOTHING:
2392 case SG_SCSI_RESET_DEVICE:
2393 rtn = scsi_try_bus_device_reset(scmd);
2394 if (rtn == SUCCESS || (val & SG_SCSI_RESET_NO_ESCALATE))
2397 case SG_SCSI_RESET_TARGET:
2398 rtn = scsi_try_target_reset(scmd);
2399 if (rtn == SUCCESS || (val & SG_SCSI_RESET_NO_ESCALATE))
2402 case SG_SCSI_RESET_BUS:
2403 rtn = scsi_try_bus_reset(scmd);
2404 if (rtn == SUCCESS || (val & SG_SCSI_RESET_NO_ESCALATE))
2407 case SG_SCSI_RESET_HOST:
2408 rtn = scsi_try_host_reset(scmd);
2417 error = (rtn == SUCCESS) ? 0 : -EIO;
2419 spin_lock_irqsave(shost->host_lock, flags);
2420 shost->tmf_in_progress = 0;
2421 spin_unlock_irqrestore(shost->host_lock, flags);
2424 * be sure to wake up anyone who was sleeping or had their queue
2425 * suspended while we performed the TMF.
2427 SCSI_LOG_ERROR_RECOVERY(3,
2428 shost_printk(KERN_INFO, shost,
2429 "waking up host to restart after TMF\n"));
2431 wake_up(&shost->host_wait);
2432 scsi_run_host_queues(shost);
2436 out_put_autopm_host:
2437 scsi_autopm_put_host(shost);
2441 bool scsi_command_normalize_sense(const struct scsi_cmnd *cmd,
2442 struct scsi_sense_hdr *sshdr)
2444 return scsi_normalize_sense(cmd->sense_buffer,
2445 SCSI_SENSE_BUFFERSIZE, sshdr);
2447 EXPORT_SYMBOL(scsi_command_normalize_sense);
2450 * scsi_get_sense_info_fld - get information field from sense data (either fixed or descriptor format)
2451 * @sense_buffer: byte array of sense data
2452 * @sb_len: number of valid bytes in sense_buffer
2453 * @info_out: pointer to 64 integer where 8 or 4 byte information
2454 * field will be placed if found.
2457 * true if information field found, false if not found.
2459 bool scsi_get_sense_info_fld(const u8 *sense_buffer, int sb_len,
2466 switch (sense_buffer[0] & 0x7f) {
2469 if (sense_buffer[0] & 0x80) {
2470 *info_out = get_unaligned_be32(&sense_buffer[3]);
2476 ucp = scsi_sense_desc_find(sense_buffer, sb_len,
2478 if (ucp && (0xa == ucp[1])) {
2479 *info_out = get_unaligned_be64(&ucp[4]);
2487 EXPORT_SYMBOL(scsi_get_sense_info_fld);