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>
53 static void scsi_eh_done(struct scsi_cmnd *scmd);
56 * These should *probably* be handled by the host itself.
57 * Since it is allowed to sleep, it probably should.
59 #define BUS_RESET_SETTLE_TIME (10)
60 #define HOST_RESET_SETTLE_TIME (10)
62 static int scsi_eh_try_stu(struct scsi_cmnd *scmd);
63 static int scsi_try_to_abort_cmd(struct scsi_host_template *,
66 void scsi_eh_wakeup(struct Scsi_Host *shost)
68 lockdep_assert_held(shost->host_lock);
70 if (scsi_host_busy(shost) == shost->host_failed) {
71 trace_scsi_eh_wakeup(shost);
72 wake_up_process(shost->ehandler);
73 SCSI_LOG_ERROR_RECOVERY(5, shost_printk(KERN_INFO, shost,
74 "Waking error handler thread\n"));
79 * scsi_schedule_eh - schedule EH for SCSI host
80 * @shost: SCSI host to invoke error handling on.
82 * Schedule SCSI EH without scmd.
84 void scsi_schedule_eh(struct Scsi_Host *shost)
88 spin_lock_irqsave(shost->host_lock, flags);
90 if (scsi_host_set_state(shost, SHOST_RECOVERY) == 0 ||
91 scsi_host_set_state(shost, SHOST_CANCEL_RECOVERY) == 0) {
92 shost->host_eh_scheduled++;
93 scsi_eh_wakeup(shost);
96 spin_unlock_irqrestore(shost->host_lock, flags);
98 EXPORT_SYMBOL_GPL(scsi_schedule_eh);
100 static int scsi_host_eh_past_deadline(struct Scsi_Host *shost)
102 if (!shost->last_reset || shost->eh_deadline == -1)
106 * 32bit accesses are guaranteed to be atomic
107 * (on all supported architectures), so instead
108 * of using a spinlock we can as well double check
109 * if eh_deadline has been set to 'off' during the
112 if (time_before(jiffies, shost->last_reset + shost->eh_deadline) &&
113 shost->eh_deadline > -1)
120 * scmd_eh_abort_handler - Handle command aborts
121 * @work: command to be aborted.
123 * Note: this function must be called only for a command that has timed out.
124 * Because the block layer marks a request as complete before it calls
125 * scsi_times_out(), a .scsi_done() call from the LLD for a command that has
126 * timed out do not have any effect. Hence it is safe to call
127 * scsi_finish_command() from this function.
130 scmd_eh_abort_handler(struct work_struct *work)
132 struct scsi_cmnd *scmd =
133 container_of(work, struct scsi_cmnd, abort_work.work);
134 struct scsi_device *sdev = scmd->device;
137 if (scsi_host_eh_past_deadline(sdev->host)) {
138 SCSI_LOG_ERROR_RECOVERY(3,
139 scmd_printk(KERN_INFO, scmd,
140 "eh timeout, not aborting\n"));
142 SCSI_LOG_ERROR_RECOVERY(3,
143 scmd_printk(KERN_INFO, scmd,
144 "aborting command\n"));
145 rtn = scsi_try_to_abort_cmd(sdev->host->hostt, scmd);
146 if (rtn == SUCCESS) {
147 set_host_byte(scmd, DID_TIME_OUT);
148 if (scsi_host_eh_past_deadline(sdev->host)) {
149 SCSI_LOG_ERROR_RECOVERY(3,
150 scmd_printk(KERN_INFO, scmd,
151 "eh timeout, not retrying "
152 "aborted command\n"));
153 } else if (!scsi_noretry_cmd(scmd) &&
154 (++scmd->retries <= scmd->allowed)) {
155 SCSI_LOG_ERROR_RECOVERY(3,
156 scmd_printk(KERN_WARNING, scmd,
157 "retry aborted command\n"));
158 scsi_queue_insert(scmd, SCSI_MLQUEUE_EH_RETRY);
161 SCSI_LOG_ERROR_RECOVERY(3,
162 scmd_printk(KERN_WARNING, scmd,
163 "finish aborted command\n"));
164 scsi_finish_command(scmd);
168 SCSI_LOG_ERROR_RECOVERY(3,
169 scmd_printk(KERN_INFO, scmd,
171 (rtn == FAST_IO_FAIL) ?
172 "not send" : "failed"));
176 scsi_eh_scmd_add(scmd);
180 * scsi_abort_command - schedule a command abort
181 * @scmd: scmd to abort.
183 * We only need to abort commands after a command timeout
186 scsi_abort_command(struct scsi_cmnd *scmd)
188 struct scsi_device *sdev = scmd->device;
189 struct Scsi_Host *shost = sdev->host;
192 if (scmd->eh_eflags & SCSI_EH_ABORT_SCHEDULED) {
194 * Retry after abort failed, escalate to next level.
196 SCSI_LOG_ERROR_RECOVERY(3,
197 scmd_printk(KERN_INFO, scmd,
198 "previous abort failed\n"));
199 BUG_ON(delayed_work_pending(&scmd->abort_work));
203 spin_lock_irqsave(shost->host_lock, flags);
204 if (shost->eh_deadline != -1 && !shost->last_reset)
205 shost->last_reset = jiffies;
206 spin_unlock_irqrestore(shost->host_lock, flags);
208 scmd->eh_eflags |= SCSI_EH_ABORT_SCHEDULED;
209 SCSI_LOG_ERROR_RECOVERY(3,
210 scmd_printk(KERN_INFO, scmd, "abort scheduled\n"));
211 queue_delayed_work(shost->tmf_work_q, &scmd->abort_work, HZ / 100);
216 * scsi_eh_reset - call into ->eh_action to reset internal counters
217 * @scmd: scmd to run eh on.
219 * The scsi driver might be carrying internal state about the
220 * devices, so we need to call into the driver to reset the
221 * internal state once the error handler is started.
223 static void scsi_eh_reset(struct scsi_cmnd *scmd)
225 if (!blk_rq_is_passthrough(scmd->request)) {
226 struct scsi_driver *sdrv = scsi_cmd_to_driver(scmd);
228 sdrv->eh_reset(scmd);
232 static void scsi_eh_inc_host_failed(struct rcu_head *head)
234 struct scsi_cmnd *scmd = container_of(head, typeof(*scmd), rcu);
235 struct Scsi_Host *shost = scmd->device->host;
238 spin_lock_irqsave(shost->host_lock, flags);
239 shost->host_failed++;
240 scsi_eh_wakeup(shost);
241 spin_unlock_irqrestore(shost->host_lock, flags);
245 * scsi_eh_scmd_add - add scsi cmd to error handling.
246 * @scmd: scmd to run eh on.
248 void scsi_eh_scmd_add(struct scsi_cmnd *scmd)
250 struct Scsi_Host *shost = scmd->device->host;
254 WARN_ON_ONCE(!shost->ehandler);
256 spin_lock_irqsave(shost->host_lock, flags);
257 if (scsi_host_set_state(shost, SHOST_RECOVERY)) {
258 ret = scsi_host_set_state(shost, SHOST_CANCEL_RECOVERY);
261 if (shost->eh_deadline != -1 && !shost->last_reset)
262 shost->last_reset = jiffies;
265 list_add_tail(&scmd->eh_entry, &shost->eh_cmd_q);
266 spin_unlock_irqrestore(shost->host_lock, flags);
268 * Ensure that all tasks observe the host state change before the
269 * host_failed change.
271 call_rcu(&scmd->rcu, scsi_eh_inc_host_failed);
275 * scsi_times_out - Timeout function for normal scsi commands.
276 * @req: request that is timing out.
279 * We do not need to lock this. There is the potential for a race
280 * only in that the normal completion handling might run, but if the
281 * normal completion function determines that the timer has already
282 * fired, then it mustn't do anything.
284 enum blk_eh_timer_return scsi_times_out(struct request *req)
286 struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(req);
287 enum blk_eh_timer_return rtn = BLK_EH_DONE;
288 struct Scsi_Host *host = scmd->device->host;
290 trace_scsi_dispatch_cmd_timeout(scmd);
291 scsi_log_completion(scmd, TIMEOUT_ERROR);
293 if (host->eh_deadline != -1 && !host->last_reset)
294 host->last_reset = jiffies;
296 if (host->hostt->eh_timed_out)
297 rtn = host->hostt->eh_timed_out(scmd);
299 if (rtn == BLK_EH_DONE) {
301 * Set the command to complete first in order to prevent a real
302 * completion from releasing the command while error handling
303 * is using it. If the command was already completed, then the
304 * lower level driver beat the timeout handler, and it is safe
305 * to return without escalating error recovery.
307 * If timeout handling lost the race to a real completion, the
308 * block layer may ignore that due to a fake timeout injection,
309 * so return RESET_TIMER to allow error handling another shot
312 if (test_and_set_bit(SCMD_STATE_COMPLETE, &scmd->state))
313 return BLK_EH_RESET_TIMER;
314 if (scsi_abort_command(scmd) != SUCCESS) {
315 set_host_byte(scmd, DID_TIME_OUT);
316 scsi_eh_scmd_add(scmd);
324 * scsi_block_when_processing_errors - Prevent cmds from being queued.
325 * @sdev: Device on which we are performing recovery.
328 * We block until the host is out of error recovery, and then check to
329 * see whether the host or the device is offline.
332 * 0 when dev was taken offline by error recovery. 1 OK to proceed.
334 int scsi_block_when_processing_errors(struct scsi_device *sdev)
338 wait_event(sdev->host->host_wait, !scsi_host_in_recovery(sdev->host));
340 online = scsi_device_online(sdev);
344 EXPORT_SYMBOL(scsi_block_when_processing_errors);
346 #ifdef CONFIG_SCSI_LOGGING
348 * scsi_eh_prt_fail_stats - Log info on failures.
349 * @shost: scsi host being recovered.
350 * @work_q: Queue of scsi cmds to process.
352 static inline void scsi_eh_prt_fail_stats(struct Scsi_Host *shost,
353 struct list_head *work_q)
355 struct scsi_cmnd *scmd;
356 struct scsi_device *sdev;
357 int total_failures = 0;
360 int devices_failed = 0;
362 shost_for_each_device(sdev, shost) {
363 list_for_each_entry(scmd, work_q, eh_entry) {
364 if (scmd->device == sdev) {
366 if (scmd->eh_eflags & SCSI_EH_ABORT_SCHEDULED)
373 if (cmd_cancel || cmd_failed) {
374 SCSI_LOG_ERROR_RECOVERY(3,
375 shost_printk(KERN_INFO, shost,
376 "%s: cmds failed: %d, cancel: %d\n",
377 __func__, cmd_failed,
385 SCSI_LOG_ERROR_RECOVERY(2, shost_printk(KERN_INFO, shost,
386 "Total of %d commands on %d"
387 " devices require eh work\n",
388 total_failures, devices_failed));
393 * scsi_report_lun_change - Set flag on all *other* devices on the same target
394 * to indicate that a UNIT ATTENTION is expected.
395 * @sdev: Device reporting the UNIT ATTENTION
397 static void scsi_report_lun_change(struct scsi_device *sdev)
399 sdev->sdev_target->expecting_lun_change = 1;
403 * scsi_report_sense - Examine scsi sense information and log messages for
404 * certain conditions, also issue uevents for some of them.
405 * @sdev: Device reporting the sense code
406 * @sshdr: sshdr to be examined
408 static void scsi_report_sense(struct scsi_device *sdev,
409 struct scsi_sense_hdr *sshdr)
411 enum scsi_device_event evt_type = SDEV_EVT_MAXBITS; /* i.e. none */
413 if (sshdr->sense_key == UNIT_ATTENTION) {
414 if (sshdr->asc == 0x3f && sshdr->ascq == 0x03) {
415 evt_type = SDEV_EVT_INQUIRY_CHANGE_REPORTED;
416 sdev_printk(KERN_WARNING, sdev,
417 "Inquiry data has changed");
418 } else if (sshdr->asc == 0x3f && sshdr->ascq == 0x0e) {
419 evt_type = SDEV_EVT_LUN_CHANGE_REPORTED;
420 scsi_report_lun_change(sdev);
421 sdev_printk(KERN_WARNING, sdev,
422 "Warning! Received an indication that the "
423 "LUN assignments on this target have "
424 "changed. The Linux SCSI layer does not "
425 "automatically remap LUN assignments.\n");
426 } else if (sshdr->asc == 0x3f)
427 sdev_printk(KERN_WARNING, sdev,
428 "Warning! Received an indication that the "
429 "operating parameters on this target have "
430 "changed. The Linux SCSI layer does not "
431 "automatically adjust these parameters.\n");
433 if (sshdr->asc == 0x38 && sshdr->ascq == 0x07) {
434 evt_type = SDEV_EVT_SOFT_THRESHOLD_REACHED_REPORTED;
435 sdev_printk(KERN_WARNING, sdev,
436 "Warning! Received an indication that the "
437 "LUN reached a thin provisioning soft "
441 if (sshdr->asc == 0x29) {
442 evt_type = SDEV_EVT_POWER_ON_RESET_OCCURRED;
443 sdev_printk(KERN_WARNING, sdev,
444 "Power-on or device reset occurred\n");
447 if (sshdr->asc == 0x2a && sshdr->ascq == 0x01) {
448 evt_type = SDEV_EVT_MODE_PARAMETER_CHANGE_REPORTED;
449 sdev_printk(KERN_WARNING, sdev,
450 "Mode parameters changed");
451 } else if (sshdr->asc == 0x2a && sshdr->ascq == 0x06) {
452 evt_type = SDEV_EVT_ALUA_STATE_CHANGE_REPORTED;
453 sdev_printk(KERN_WARNING, sdev,
454 "Asymmetric access state changed");
455 } else if (sshdr->asc == 0x2a && sshdr->ascq == 0x09) {
456 evt_type = SDEV_EVT_CAPACITY_CHANGE_REPORTED;
457 sdev_printk(KERN_WARNING, sdev,
458 "Capacity data has changed");
459 } else if (sshdr->asc == 0x2a)
460 sdev_printk(KERN_WARNING, sdev,
461 "Parameters changed");
464 if (evt_type != SDEV_EVT_MAXBITS) {
465 set_bit(evt_type, sdev->pending_events);
466 schedule_work(&sdev->event_work);
471 * scsi_check_sense - Examine scsi cmd sense
472 * @scmd: Cmd to have sense checked.
475 * SUCCESS or FAILED or NEEDS_RETRY or ADD_TO_MLQUEUE
478 * When a deferred error is detected the current command has
479 * not been executed and needs retrying.
481 int scsi_check_sense(struct scsi_cmnd *scmd)
483 struct scsi_device *sdev = scmd->device;
484 struct scsi_sense_hdr sshdr;
486 if (! scsi_command_normalize_sense(scmd, &sshdr))
487 return FAILED; /* no valid sense data */
489 scsi_report_sense(sdev, &sshdr);
491 if (scsi_sense_is_deferred(&sshdr))
494 if (sdev->handler && sdev->handler->check_sense) {
497 rc = sdev->handler->check_sense(sdev, &sshdr);
498 if (rc != SCSI_RETURN_NOT_HANDLED)
500 /* handler does not care. Drop down to default handling */
503 if (scmd->cmnd[0] == TEST_UNIT_READY && scmd->scsi_done != scsi_eh_done)
505 * nasty: for mid-layer issued TURs, we need to return the
506 * actual sense data without any recovery attempt. For eh
507 * issued ones, we need to try to recover and interpret
512 * Previous logic looked for FILEMARK, EOM or ILI which are
513 * mainly associated with tapes and returned SUCCESS.
515 if (sshdr.response_code == 0x70) {
517 if (scmd->sense_buffer[2] & 0xe0)
521 * descriptor format: look for "stream commands sense data
522 * descriptor" (see SSC-3). Assume single sense data
523 * descriptor. Ignore ILI from SBC-2 READ LONG and WRITE LONG.
525 if ((sshdr.additional_length > 3) &&
526 (scmd->sense_buffer[8] == 0x4) &&
527 (scmd->sense_buffer[11] & 0xe0))
531 switch (sshdr.sense_key) {
534 case RECOVERED_ERROR:
535 return /* soft_error */ SUCCESS;
537 case ABORTED_COMMAND:
538 if (sshdr.asc == 0x10) /* DIF */
541 if (sshdr.asc == 0x44 && sdev->sdev_bflags & BLIST_RETRY_ITF)
542 return ADD_TO_MLQUEUE;
543 if (sshdr.asc == 0xc1 && sshdr.ascq == 0x01 &&
544 sdev->sdev_bflags & BLIST_RETRY_ASC_C1)
545 return ADD_TO_MLQUEUE;
551 * if we are expecting a cc/ua because of a bus reset that we
552 * performed, treat this just as a retry. otherwise this is
553 * information that we should pass up to the upper-level driver
554 * so that we can deal with it there.
556 if (scmd->device->expecting_cc_ua) {
558 * Because some device does not queue unit
559 * attentions correctly, we carefully check
560 * additional sense code and qualifier so as
561 * not to squash media change unit attention.
563 if (sshdr.asc != 0x28 || sshdr.ascq != 0x00) {
564 scmd->device->expecting_cc_ua = 0;
569 * we might also expect a cc/ua if another LUN on the target
570 * reported a UA with an ASC/ASCQ of 3F 0E -
571 * REPORTED LUNS DATA HAS CHANGED.
573 if (scmd->device->sdev_target->expecting_lun_change &&
574 sshdr.asc == 0x3f && sshdr.ascq == 0x0e)
577 * if the device is in the process of becoming ready, we
580 if ((sshdr.asc == 0x04) && (sshdr.ascq == 0x01))
583 * if the device is not started, we need to wake
584 * the error handler to start the motor
586 if (scmd->device->allow_restart &&
587 (sshdr.asc == 0x04) && (sshdr.ascq == 0x02))
590 * Pass the UA upwards for a determination in the completion
595 /* these are not supported */
597 if (sshdr.asc == 0x27 && sshdr.ascq == 0x07) {
598 /* Thin provisioning hard threshold reached */
599 set_host_byte(scmd, DID_ALLOC_FAILURE);
604 case VOLUME_OVERFLOW:
607 set_host_byte(scmd, DID_TARGET_FAILURE);
611 if (sshdr.asc == 0x11 || /* UNRECOVERED READ ERR */
612 sshdr.asc == 0x13 || /* AMNF DATA FIELD */
613 sshdr.asc == 0x14) { /* RECORD NOT FOUND */
614 set_host_byte(scmd, DID_MEDIUM_ERROR);
620 if (scmd->device->retry_hwerror)
621 return ADD_TO_MLQUEUE;
623 set_host_byte(scmd, DID_TARGET_FAILURE);
626 case ILLEGAL_REQUEST:
627 if (sshdr.asc == 0x20 || /* Invalid command operation code */
628 sshdr.asc == 0x21 || /* Logical block address out of range */
629 sshdr.asc == 0x22 || /* Invalid function */
630 sshdr.asc == 0x24 || /* Invalid field in cdb */
631 sshdr.asc == 0x26 || /* Parameter value invalid */
632 sshdr.asc == 0x27) { /* Write protected */
633 set_host_byte(scmd, DID_TARGET_FAILURE);
641 EXPORT_SYMBOL_GPL(scsi_check_sense);
643 static void scsi_handle_queue_ramp_up(struct scsi_device *sdev)
645 struct scsi_host_template *sht = sdev->host->hostt;
646 struct scsi_device *tmp_sdev;
648 if (!sht->track_queue_depth ||
649 sdev->queue_depth >= sdev->max_queue_depth)
652 if (time_before(jiffies,
653 sdev->last_queue_ramp_up + sdev->queue_ramp_up_period))
656 if (time_before(jiffies,
657 sdev->last_queue_full_time + sdev->queue_ramp_up_period))
661 * Walk all devices of a target and do
664 shost_for_each_device(tmp_sdev, sdev->host) {
665 if (tmp_sdev->channel != sdev->channel ||
666 tmp_sdev->id != sdev->id ||
667 tmp_sdev->queue_depth == sdev->max_queue_depth)
670 scsi_change_queue_depth(tmp_sdev, tmp_sdev->queue_depth + 1);
671 sdev->last_queue_ramp_up = jiffies;
675 static void scsi_handle_queue_full(struct scsi_device *sdev)
677 struct scsi_host_template *sht = sdev->host->hostt;
678 struct scsi_device *tmp_sdev;
680 if (!sht->track_queue_depth)
683 shost_for_each_device(tmp_sdev, sdev->host) {
684 if (tmp_sdev->channel != sdev->channel ||
685 tmp_sdev->id != sdev->id)
688 * We do not know the number of commands that were at
689 * the device when we got the queue full so we start
690 * from the highest possible value and work our way down.
692 scsi_track_queue_full(tmp_sdev, tmp_sdev->queue_depth - 1);
697 * scsi_eh_completed_normally - Disposition a eh cmd on return from LLD.
698 * @scmd: SCSI cmd to examine.
701 * This is *only* called when we are examining the status of commands
702 * queued during error recovery. the main difference here is that we
703 * don't allow for the possibility of retries here, and we are a lot
704 * more restrictive about what we consider acceptable.
706 static int scsi_eh_completed_normally(struct scsi_cmnd *scmd)
709 * first check the host byte, to see if there is anything in there
710 * that would indicate what we need to do.
712 if (host_byte(scmd->result) == DID_RESET) {
714 * rats. we are already in the error handler, so we now
715 * get to try and figure out what to do next. if the sense
716 * is valid, we have a pretty good idea of what to do.
717 * if not, we mark it as FAILED.
719 return scsi_check_sense(scmd);
721 if (host_byte(scmd->result) != DID_OK)
725 * next, check the message byte.
727 if (msg_byte(scmd->result) != COMMAND_COMPLETE)
731 * now, check the status byte to see if this indicates
734 switch (status_byte(scmd->result)) {
736 scsi_handle_queue_ramp_up(scmd->device);
738 case COMMAND_TERMINATED:
740 case CHECK_CONDITION:
741 return scsi_check_sense(scmd);
743 case INTERMEDIATE_GOOD:
744 case INTERMEDIATE_C_GOOD:
746 * who knows? FIXME(eric)
749 case RESERVATION_CONFLICT:
750 if (scmd->cmnd[0] == TEST_UNIT_READY)
751 /* it is a success, we probed the device and
754 /* otherwise, we failed to send the command */
757 scsi_handle_queue_full(scmd->device);
768 * scsi_eh_done - Completion function for error handling.
769 * @scmd: Cmd that is done.
771 static void scsi_eh_done(struct scsi_cmnd *scmd)
773 struct completion *eh_action;
775 SCSI_LOG_ERROR_RECOVERY(3, scmd_printk(KERN_INFO, scmd,
776 "%s result: %x\n", __func__, scmd->result));
778 eh_action = scmd->device->host->eh_action;
784 * scsi_try_host_reset - ask host adapter to reset itself
785 * @scmd: SCSI cmd to send host reset.
787 static int scsi_try_host_reset(struct scsi_cmnd *scmd)
791 struct Scsi_Host *host = scmd->device->host;
792 struct scsi_host_template *hostt = host->hostt;
794 SCSI_LOG_ERROR_RECOVERY(3,
795 shost_printk(KERN_INFO, host, "Snd Host RST\n"));
797 if (!hostt->eh_host_reset_handler)
800 rtn = hostt->eh_host_reset_handler(scmd);
802 if (rtn == SUCCESS) {
803 if (!hostt->skip_settle_delay)
804 ssleep(HOST_RESET_SETTLE_TIME);
805 spin_lock_irqsave(host->host_lock, flags);
806 scsi_report_bus_reset(host, scmd_channel(scmd));
807 spin_unlock_irqrestore(host->host_lock, flags);
814 * scsi_try_bus_reset - ask host to perform a bus reset
815 * @scmd: SCSI cmd to send bus reset.
817 static int scsi_try_bus_reset(struct scsi_cmnd *scmd)
821 struct Scsi_Host *host = scmd->device->host;
822 struct scsi_host_template *hostt = host->hostt;
824 SCSI_LOG_ERROR_RECOVERY(3, scmd_printk(KERN_INFO, scmd,
825 "%s: Snd Bus RST\n", __func__));
827 if (!hostt->eh_bus_reset_handler)
830 rtn = hostt->eh_bus_reset_handler(scmd);
832 if (rtn == SUCCESS) {
833 if (!hostt->skip_settle_delay)
834 ssleep(BUS_RESET_SETTLE_TIME);
835 spin_lock_irqsave(host->host_lock, flags);
836 scsi_report_bus_reset(host, scmd_channel(scmd));
837 spin_unlock_irqrestore(host->host_lock, flags);
843 static void __scsi_report_device_reset(struct scsi_device *sdev, void *data)
846 sdev->expecting_cc_ua = 1;
850 * scsi_try_target_reset - Ask host to perform a target reset
851 * @scmd: SCSI cmd used to send a target reset
854 * There is no timeout for this operation. if this operation is
855 * unreliable for a given host, then the host itself needs to put a
856 * timer on it, and set the host back to a consistent state prior to
859 static int scsi_try_target_reset(struct scsi_cmnd *scmd)
863 struct Scsi_Host *host = scmd->device->host;
864 struct scsi_host_template *hostt = host->hostt;
866 if (!hostt->eh_target_reset_handler)
869 rtn = hostt->eh_target_reset_handler(scmd);
870 if (rtn == SUCCESS) {
871 spin_lock_irqsave(host->host_lock, flags);
872 __starget_for_each_device(scsi_target(scmd->device), NULL,
873 __scsi_report_device_reset);
874 spin_unlock_irqrestore(host->host_lock, flags);
881 * scsi_try_bus_device_reset - Ask host to perform a BDR on a dev
882 * @scmd: SCSI cmd used to send BDR
885 * There is no timeout for this operation. if this operation is
886 * unreliable for a given host, then the host itself needs to put a
887 * timer on it, and set the host back to a consistent state prior to
890 static int scsi_try_bus_device_reset(struct scsi_cmnd *scmd)
893 struct scsi_host_template *hostt = scmd->device->host->hostt;
895 if (!hostt->eh_device_reset_handler)
898 rtn = hostt->eh_device_reset_handler(scmd);
900 __scsi_report_device_reset(scmd->device, NULL);
905 * scsi_try_to_abort_cmd - Ask host to abort a SCSI command
906 * @hostt: SCSI driver host template
907 * @scmd: SCSI cmd used to send a target reset
910 * SUCCESS, FAILED, or FAST_IO_FAIL
913 * SUCCESS does not necessarily indicate that the command
914 * has been aborted; it only indicates that the LLDDs
915 * has cleared all references to that command.
916 * LLDDs should return FAILED only if an abort was required
917 * but could not be executed. LLDDs should return FAST_IO_FAIL
918 * if the device is temporarily unavailable (eg due to a
919 * link down on FibreChannel)
921 static int scsi_try_to_abort_cmd(struct scsi_host_template *hostt,
922 struct scsi_cmnd *scmd)
924 if (!hostt->eh_abort_handler)
927 return hostt->eh_abort_handler(scmd);
930 static void scsi_abort_eh_cmnd(struct scsi_cmnd *scmd)
932 if (scsi_try_to_abort_cmd(scmd->device->host->hostt, scmd) != SUCCESS)
933 if (scsi_try_bus_device_reset(scmd) != SUCCESS)
934 if (scsi_try_target_reset(scmd) != SUCCESS)
935 if (scsi_try_bus_reset(scmd) != SUCCESS)
936 scsi_try_host_reset(scmd);
940 * scsi_eh_prep_cmnd - Save a scsi command info as part of error recovery
941 * @scmd: SCSI command structure to hijack
942 * @ses: structure to save restore information
943 * @cmnd: CDB to send. Can be NULL if no new cmnd is needed
944 * @cmnd_size: size in bytes of @cmnd (must be <= BLK_MAX_CDB)
945 * @sense_bytes: size of sense data to copy. or 0 (if != 0 @cmnd is ignored)
947 * This function is used to save a scsi command information before re-execution
948 * as part of the error recovery process. If @sense_bytes is 0 the command
949 * sent must be one that does not transfer any data. If @sense_bytes != 0
950 * @cmnd is ignored and this functions sets up a REQUEST_SENSE command
951 * and cmnd buffers to read @sense_bytes into @scmd->sense_buffer.
953 void scsi_eh_prep_cmnd(struct scsi_cmnd *scmd, struct scsi_eh_save *ses,
954 unsigned char *cmnd, int cmnd_size, unsigned sense_bytes)
956 struct scsi_device *sdev = scmd->device;
959 * We need saved copies of a number of fields - this is because
960 * error handling may need to overwrite these with different values
961 * to run different commands, and once error handling is complete,
962 * we will need to restore these values prior to running the actual
965 ses->cmd_len = scmd->cmd_len;
966 ses->cmnd = scmd->cmnd;
967 ses->data_direction = scmd->sc_data_direction;
968 ses->sdb = scmd->sdb;
969 ses->result = scmd->result;
970 ses->underflow = scmd->underflow;
971 ses->prot_op = scmd->prot_op;
972 ses->eh_eflags = scmd->eh_eflags;
974 scmd->prot_op = SCSI_PROT_NORMAL;
976 scmd->cmnd = ses->eh_cmnd;
977 memset(scmd->cmnd, 0, BLK_MAX_CDB);
978 memset(&scmd->sdb, 0, sizeof(scmd->sdb));
982 scmd->sdb.length = min_t(unsigned, SCSI_SENSE_BUFFERSIZE,
984 sg_init_one(&ses->sense_sgl, scmd->sense_buffer,
986 scmd->sdb.table.sgl = &ses->sense_sgl;
987 scmd->sc_data_direction = DMA_FROM_DEVICE;
988 scmd->sdb.table.nents = scmd->sdb.table.orig_nents = 1;
989 scmd->cmnd[0] = REQUEST_SENSE;
990 scmd->cmnd[4] = scmd->sdb.length;
991 scmd->cmd_len = COMMAND_SIZE(scmd->cmnd[0]);
993 scmd->sc_data_direction = DMA_NONE;
995 BUG_ON(cmnd_size > BLK_MAX_CDB);
996 memcpy(scmd->cmnd, cmnd, cmnd_size);
997 scmd->cmd_len = COMMAND_SIZE(scmd->cmnd[0]);
1001 scmd->underflow = 0;
1003 if (sdev->scsi_level <= SCSI_2 && sdev->scsi_level != SCSI_UNKNOWN)
1004 scmd->cmnd[1] = (scmd->cmnd[1] & 0x1f) |
1005 (sdev->lun << 5 & 0xe0);
1008 * Zero the sense buffer. The scsi spec mandates that any
1009 * untransferred sense data should be interpreted as being zero.
1011 memset(scmd->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE);
1013 EXPORT_SYMBOL(scsi_eh_prep_cmnd);
1016 * scsi_eh_restore_cmnd - Restore a scsi command info as part of error recovery
1017 * @scmd: SCSI command structure to restore
1018 * @ses: saved information from a coresponding call to scsi_eh_prep_cmnd
1020 * Undo any damage done by above scsi_eh_prep_cmnd().
1022 void scsi_eh_restore_cmnd(struct scsi_cmnd* scmd, struct scsi_eh_save *ses)
1025 * Restore original data
1027 scmd->cmd_len = ses->cmd_len;
1028 scmd->cmnd = ses->cmnd;
1029 scmd->sc_data_direction = ses->data_direction;
1030 scmd->sdb = ses->sdb;
1031 scmd->result = ses->result;
1032 scmd->underflow = ses->underflow;
1033 scmd->prot_op = ses->prot_op;
1034 scmd->eh_eflags = ses->eh_eflags;
1036 EXPORT_SYMBOL(scsi_eh_restore_cmnd);
1039 * scsi_send_eh_cmnd - submit a scsi command as part of error recovery
1040 * @scmd: SCSI command structure to hijack
1041 * @cmnd: CDB to send
1042 * @cmnd_size: size in bytes of @cmnd
1043 * @timeout: timeout for this request
1044 * @sense_bytes: size of sense data to copy or 0
1046 * This function is used to send a scsi command down to a target device
1047 * as part of the error recovery process. See also scsi_eh_prep_cmnd() above.
1050 * SUCCESS or FAILED or NEEDS_RETRY
1052 static int scsi_send_eh_cmnd(struct scsi_cmnd *scmd, unsigned char *cmnd,
1053 int cmnd_size, int timeout, unsigned sense_bytes)
1055 struct scsi_device *sdev = scmd->device;
1056 struct Scsi_Host *shost = sdev->host;
1057 DECLARE_COMPLETION_ONSTACK(done);
1058 unsigned long timeleft = timeout, delay;
1059 struct scsi_eh_save ses;
1060 const unsigned long stall_for = msecs_to_jiffies(100);
1064 scsi_eh_prep_cmnd(scmd, &ses, cmnd, cmnd_size, sense_bytes);
1065 shost->eh_action = &done;
1067 scsi_log_send(scmd);
1068 scmd->scsi_done = scsi_eh_done;
1071 * Lock sdev->state_mutex to avoid that scsi_device_quiesce() can
1072 * change the SCSI device state after we have examined it and before
1073 * .queuecommand() is called.
1075 mutex_lock(&sdev->state_mutex);
1076 while (sdev->sdev_state == SDEV_BLOCK && timeleft > 0) {
1077 mutex_unlock(&sdev->state_mutex);
1078 SCSI_LOG_ERROR_RECOVERY(5, sdev_printk(KERN_DEBUG, sdev,
1079 "%s: state %d <> %d\n", __func__, sdev->sdev_state,
1081 delay = min(timeleft, stall_for);
1083 msleep(jiffies_to_msecs(delay));
1084 mutex_lock(&sdev->state_mutex);
1086 if (sdev->sdev_state != SDEV_BLOCK)
1087 rtn = shost->hostt->queuecommand(shost, scmd);
1089 rtn = SCSI_MLQUEUE_DEVICE_BUSY;
1090 mutex_unlock(&sdev->state_mutex);
1093 if (timeleft > stall_for) {
1094 scsi_eh_restore_cmnd(scmd, &ses);
1095 timeleft -= stall_for;
1096 msleep(jiffies_to_msecs(stall_for));
1099 /* signal not to enter either branch of the if () below */
1103 timeleft = wait_for_completion_timeout(&done, timeout);
1107 shost->eh_action = NULL;
1109 scsi_log_completion(scmd, rtn);
1111 SCSI_LOG_ERROR_RECOVERY(3, scmd_printk(KERN_INFO, scmd,
1112 "%s timeleft: %ld\n",
1113 __func__, timeleft));
1116 * If there is time left scsi_eh_done got called, and we will examine
1117 * the actual status codes to see whether the command actually did
1118 * complete normally, else if we have a zero return and no time left,
1119 * the command must still be pending, so abort it and return FAILED.
1120 * If we never actually managed to issue the command, because
1121 * ->queuecommand() kept returning non zero, use the rtn = FAILED
1122 * value above (so don't execute either branch of the if)
1125 rtn = scsi_eh_completed_normally(scmd);
1126 SCSI_LOG_ERROR_RECOVERY(3, scmd_printk(KERN_INFO, scmd,
1127 "%s: scsi_eh_completed_normally %x\n", __func__, rtn));
1134 case ADD_TO_MLQUEUE:
1141 } else if (rtn != FAILED) {
1142 scsi_abort_eh_cmnd(scmd);
1146 scsi_eh_restore_cmnd(scmd, &ses);
1152 * scsi_request_sense - Request sense data from a particular target.
1153 * @scmd: SCSI cmd for request sense.
1156 * Some hosts automatically obtain this information, others require
1157 * that we obtain it on our own. This function will *not* return until
1158 * the command either times out, or it completes.
1160 static int scsi_request_sense(struct scsi_cmnd *scmd)
1162 return scsi_send_eh_cmnd(scmd, NULL, 0, scmd->device->eh_timeout, ~0);
1165 static int scsi_eh_action(struct scsi_cmnd *scmd, int rtn)
1167 if (!blk_rq_is_passthrough(scmd->request)) {
1168 struct scsi_driver *sdrv = scsi_cmd_to_driver(scmd);
1169 if (sdrv->eh_action)
1170 rtn = sdrv->eh_action(scmd, rtn);
1176 * scsi_eh_finish_cmd - Handle a cmd that eh is finished with.
1177 * @scmd: Original SCSI cmd that eh has finished.
1178 * @done_q: Queue for processed commands.
1181 * We don't want to use the normal command completion while we are are
1182 * still handling errors - it may cause other commands to be queued,
1183 * and that would disturb what we are doing. Thus we really want to
1184 * keep a list of pending commands for final completion, and once we
1185 * are ready to leave error handling we handle completion for real.
1187 void scsi_eh_finish_cmd(struct scsi_cmnd *scmd, struct list_head *done_q)
1189 list_move_tail(&scmd->eh_entry, done_q);
1191 EXPORT_SYMBOL(scsi_eh_finish_cmd);
1194 * scsi_eh_get_sense - Get device sense data.
1195 * @work_q: Queue of commands to process.
1196 * @done_q: Queue of processed commands.
1199 * See if we need to request sense information. if so, then get it
1200 * now, so we have a better idea of what to do.
1203 * This has the unfortunate side effect that if a shost adapter does
1204 * not automatically request sense information, we end up shutting
1205 * it down before we request it.
1207 * All drivers should request sense information internally these days,
1208 * so for now all I have to say is tough noogies if you end up in here.
1210 * XXX: Long term this code should go away, but that needs an audit of
1213 int scsi_eh_get_sense(struct list_head *work_q,
1214 struct list_head *done_q)
1216 struct scsi_cmnd *scmd, *next;
1217 struct Scsi_Host *shost;
1221 * If SCSI_EH_ABORT_SCHEDULED has been set, it is timeout IO,
1222 * should not get sense.
1224 list_for_each_entry_safe(scmd, next, work_q, eh_entry) {
1225 if ((scmd->eh_eflags & SCSI_EH_ABORT_SCHEDULED) ||
1226 SCSI_SENSE_VALID(scmd))
1229 shost = scmd->device->host;
1230 if (scsi_host_eh_past_deadline(shost)) {
1231 SCSI_LOG_ERROR_RECOVERY(3,
1232 scmd_printk(KERN_INFO, scmd,
1233 "%s: skip request sense, past eh deadline\n",
1237 if (status_byte(scmd->result) != CHECK_CONDITION)
1239 * don't request sense if there's no check condition
1240 * status because the error we're processing isn't one
1241 * that has a sense code (and some devices get
1242 * confused by sense requests out of the blue)
1246 SCSI_LOG_ERROR_RECOVERY(2, scmd_printk(KERN_INFO, scmd,
1247 "%s: requesting sense\n",
1249 rtn = scsi_request_sense(scmd);
1253 SCSI_LOG_ERROR_RECOVERY(3, scmd_printk(KERN_INFO, scmd,
1254 "sense requested, result %x\n", scmd->result));
1255 SCSI_LOG_ERROR_RECOVERY(3, scsi_print_sense(scmd));
1257 rtn = scsi_decide_disposition(scmd);
1260 * if the result was normal, then just pass it along to the
1264 /* we don't want this command reissued, just
1265 * finished with the sense data, so set
1266 * retries to the max allowed to ensure it
1267 * won't get reissued */
1268 scmd->retries = scmd->allowed;
1269 else if (rtn != NEEDS_RETRY)
1272 scsi_eh_finish_cmd(scmd, done_q);
1275 return list_empty(work_q);
1277 EXPORT_SYMBOL_GPL(scsi_eh_get_sense);
1280 * scsi_eh_tur - Send TUR to device.
1281 * @scmd: &scsi_cmnd to send TUR
1284 * 0 - Device is ready. 1 - Device NOT ready.
1286 static int scsi_eh_tur(struct scsi_cmnd *scmd)
1288 static unsigned char tur_command[6] = {TEST_UNIT_READY, 0, 0, 0, 0, 0};
1289 int retry_cnt = 1, rtn;
1292 rtn = scsi_send_eh_cmnd(scmd, tur_command, 6,
1293 scmd->device->eh_timeout, 0);
1295 SCSI_LOG_ERROR_RECOVERY(3, scmd_printk(KERN_INFO, scmd,
1296 "%s return: %x\n", __func__, rtn));
1311 * scsi_eh_test_devices - check if devices are responding from error recovery.
1312 * @cmd_list: scsi commands in error recovery.
1313 * @work_q: queue for commands which still need more error recovery
1314 * @done_q: queue for commands which are finished
1315 * @try_stu: boolean on if a STU command should be tried in addition to TUR.
1318 * Tests if devices are in a working state. Commands to devices now in
1319 * a working state are sent to the done_q while commands to devices which
1320 * are still failing to respond are returned to the work_q for more
1323 static int scsi_eh_test_devices(struct list_head *cmd_list,
1324 struct list_head *work_q,
1325 struct list_head *done_q, int try_stu)
1327 struct scsi_cmnd *scmd, *next;
1328 struct scsi_device *sdev;
1331 while (!list_empty(cmd_list)) {
1332 scmd = list_entry(cmd_list->next, struct scsi_cmnd, eh_entry);
1333 sdev = scmd->device;
1336 if (scsi_host_eh_past_deadline(sdev->host)) {
1337 /* Push items back onto work_q */
1338 list_splice_init(cmd_list, work_q);
1339 SCSI_LOG_ERROR_RECOVERY(3,
1340 sdev_printk(KERN_INFO, sdev,
1341 "%s: skip test device, past eh deadline",
1347 finish_cmds = !scsi_device_online(scmd->device) ||
1348 (try_stu && !scsi_eh_try_stu(scmd) &&
1349 !scsi_eh_tur(scmd)) ||
1352 list_for_each_entry_safe(scmd, next, cmd_list, eh_entry)
1353 if (scmd->device == sdev) {
1356 scsi_eh_action(scmd, SUCCESS) == SUCCESS))
1357 scsi_eh_finish_cmd(scmd, done_q);
1359 list_move_tail(&scmd->eh_entry, work_q);
1362 return list_empty(work_q);
1366 * scsi_eh_try_stu - Send START_UNIT to device.
1367 * @scmd: &scsi_cmnd to send START_UNIT
1370 * 0 - Device is ready. 1 - Device NOT ready.
1372 static int scsi_eh_try_stu(struct scsi_cmnd *scmd)
1374 static unsigned char stu_command[6] = {START_STOP, 0, 0, 0, 1, 0};
1376 if (scmd->device->allow_restart) {
1377 int i, rtn = NEEDS_RETRY;
1379 for (i = 0; rtn == NEEDS_RETRY && i < 2; i++)
1380 rtn = scsi_send_eh_cmnd(scmd, stu_command, 6, scmd->device->request_queue->rq_timeout, 0);
1390 * scsi_eh_stu - send START_UNIT if needed
1391 * @shost: &scsi host being recovered.
1392 * @work_q: &list_head for pending commands.
1393 * @done_q: &list_head for processed commands.
1396 * If commands are failing due to not ready, initializing command required,
1397 * try revalidating the device, which will end up sending a start unit.
1399 static int scsi_eh_stu(struct Scsi_Host *shost,
1400 struct list_head *work_q,
1401 struct list_head *done_q)
1403 struct scsi_cmnd *scmd, *stu_scmd, *next;
1404 struct scsi_device *sdev;
1406 shost_for_each_device(sdev, shost) {
1407 if (scsi_host_eh_past_deadline(shost)) {
1408 SCSI_LOG_ERROR_RECOVERY(3,
1409 sdev_printk(KERN_INFO, sdev,
1410 "%s: skip START_UNIT, past eh deadline\n",
1415 list_for_each_entry(scmd, work_q, eh_entry)
1416 if (scmd->device == sdev && SCSI_SENSE_VALID(scmd) &&
1417 scsi_check_sense(scmd) == FAILED ) {
1425 SCSI_LOG_ERROR_RECOVERY(3,
1426 sdev_printk(KERN_INFO, sdev,
1427 "%s: Sending START_UNIT\n",
1430 if (!scsi_eh_try_stu(stu_scmd)) {
1431 if (!scsi_device_online(sdev) ||
1432 !scsi_eh_tur(stu_scmd)) {
1433 list_for_each_entry_safe(scmd, next,
1435 if (scmd->device == sdev &&
1436 scsi_eh_action(scmd, SUCCESS) == SUCCESS)
1437 scsi_eh_finish_cmd(scmd, done_q);
1441 SCSI_LOG_ERROR_RECOVERY(3,
1442 sdev_printk(KERN_INFO, sdev,
1443 "%s: START_UNIT failed\n",
1448 return list_empty(work_q);
1453 * scsi_eh_bus_device_reset - send bdr if needed
1454 * @shost: scsi host being recovered.
1455 * @work_q: &list_head for pending commands.
1456 * @done_q: &list_head for processed commands.
1459 * Try a bus device reset. Still, look to see whether we have multiple
1460 * devices that are jammed or not - if we have multiple devices, it
1461 * makes no sense to try bus_device_reset - we really would need to try
1462 * a bus_reset instead.
1464 static int scsi_eh_bus_device_reset(struct Scsi_Host *shost,
1465 struct list_head *work_q,
1466 struct list_head *done_q)
1468 struct scsi_cmnd *scmd, *bdr_scmd, *next;
1469 struct scsi_device *sdev;
1472 shost_for_each_device(sdev, shost) {
1473 if (scsi_host_eh_past_deadline(shost)) {
1474 SCSI_LOG_ERROR_RECOVERY(3,
1475 sdev_printk(KERN_INFO, sdev,
1476 "%s: skip BDR, past eh deadline\n",
1481 list_for_each_entry(scmd, work_q, eh_entry)
1482 if (scmd->device == sdev) {
1490 SCSI_LOG_ERROR_RECOVERY(3,
1491 sdev_printk(KERN_INFO, sdev,
1492 "%s: Sending BDR\n", current->comm));
1493 rtn = scsi_try_bus_device_reset(bdr_scmd);
1494 if (rtn == SUCCESS || rtn == FAST_IO_FAIL) {
1495 if (!scsi_device_online(sdev) ||
1496 rtn == FAST_IO_FAIL ||
1497 !scsi_eh_tur(bdr_scmd)) {
1498 list_for_each_entry_safe(scmd, next,
1500 if (scmd->device == sdev &&
1501 scsi_eh_action(scmd, rtn) != FAILED)
1502 scsi_eh_finish_cmd(scmd,
1507 SCSI_LOG_ERROR_RECOVERY(3,
1508 sdev_printk(KERN_INFO, sdev,
1509 "%s: BDR failed\n", current->comm));
1513 return list_empty(work_q);
1517 * scsi_eh_target_reset - send target reset if needed
1518 * @shost: scsi host being recovered.
1519 * @work_q: &list_head for pending commands.
1520 * @done_q: &list_head for processed commands.
1523 * Try a target reset.
1525 static int scsi_eh_target_reset(struct Scsi_Host *shost,
1526 struct list_head *work_q,
1527 struct list_head *done_q)
1529 LIST_HEAD(tmp_list);
1530 LIST_HEAD(check_list);
1532 list_splice_init(work_q, &tmp_list);
1534 while (!list_empty(&tmp_list)) {
1535 struct scsi_cmnd *next, *scmd;
1539 if (scsi_host_eh_past_deadline(shost)) {
1540 /* push back on work queue for further processing */
1541 list_splice_init(&check_list, work_q);
1542 list_splice_init(&tmp_list, work_q);
1543 SCSI_LOG_ERROR_RECOVERY(3,
1544 shost_printk(KERN_INFO, shost,
1545 "%s: Skip target reset, past eh deadline\n",
1547 return list_empty(work_q);
1550 scmd = list_entry(tmp_list.next, struct scsi_cmnd, eh_entry);
1553 SCSI_LOG_ERROR_RECOVERY(3,
1554 shost_printk(KERN_INFO, shost,
1555 "%s: Sending target reset to target %d\n",
1556 current->comm, id));
1557 rtn = scsi_try_target_reset(scmd);
1558 if (rtn != SUCCESS && rtn != FAST_IO_FAIL)
1559 SCSI_LOG_ERROR_RECOVERY(3,
1560 shost_printk(KERN_INFO, shost,
1561 "%s: Target reset failed"
1563 current->comm, id));
1564 list_for_each_entry_safe(scmd, next, &tmp_list, eh_entry) {
1565 if (scmd_id(scmd) != id)
1569 list_move_tail(&scmd->eh_entry, &check_list);
1570 else if (rtn == FAST_IO_FAIL)
1571 scsi_eh_finish_cmd(scmd, done_q);
1573 /* push back on work queue for further processing */
1574 list_move(&scmd->eh_entry, work_q);
1578 return scsi_eh_test_devices(&check_list, work_q, done_q, 0);
1582 * scsi_eh_bus_reset - send a bus reset
1583 * @shost: &scsi host being recovered.
1584 * @work_q: &list_head for pending commands.
1585 * @done_q: &list_head for processed commands.
1587 static int scsi_eh_bus_reset(struct Scsi_Host *shost,
1588 struct list_head *work_q,
1589 struct list_head *done_q)
1591 struct scsi_cmnd *scmd, *chan_scmd, *next;
1592 LIST_HEAD(check_list);
1593 unsigned int channel;
1597 * we really want to loop over the various channels, and do this on
1598 * a channel by channel basis. we should also check to see if any
1599 * of the failed commands are on soft_reset devices, and if so, skip
1603 for (channel = 0; channel <= shost->max_channel; channel++) {
1604 if (scsi_host_eh_past_deadline(shost)) {
1605 list_splice_init(&check_list, work_q);
1606 SCSI_LOG_ERROR_RECOVERY(3,
1607 shost_printk(KERN_INFO, shost,
1608 "%s: skip BRST, past eh deadline\n",
1610 return list_empty(work_q);
1614 list_for_each_entry(scmd, work_q, eh_entry) {
1615 if (channel == scmd_channel(scmd)) {
1619 * FIXME add back in some support for
1620 * soft_reset devices.
1627 SCSI_LOG_ERROR_RECOVERY(3,
1628 shost_printk(KERN_INFO, shost,
1629 "%s: Sending BRST chan: %d\n",
1630 current->comm, channel));
1631 rtn = scsi_try_bus_reset(chan_scmd);
1632 if (rtn == SUCCESS || rtn == FAST_IO_FAIL) {
1633 list_for_each_entry_safe(scmd, next, work_q, eh_entry) {
1634 if (channel == scmd_channel(scmd)) {
1635 if (rtn == FAST_IO_FAIL)
1636 scsi_eh_finish_cmd(scmd,
1639 list_move_tail(&scmd->eh_entry,
1644 SCSI_LOG_ERROR_RECOVERY(3,
1645 shost_printk(KERN_INFO, shost,
1646 "%s: BRST failed chan: %d\n",
1647 current->comm, channel));
1650 return scsi_eh_test_devices(&check_list, work_q, done_q, 0);
1654 * scsi_eh_host_reset - send a host reset
1655 * @shost: host to be reset.
1656 * @work_q: &list_head for pending commands.
1657 * @done_q: &list_head for processed commands.
1659 static int scsi_eh_host_reset(struct Scsi_Host *shost,
1660 struct list_head *work_q,
1661 struct list_head *done_q)
1663 struct scsi_cmnd *scmd, *next;
1664 LIST_HEAD(check_list);
1667 if (!list_empty(work_q)) {
1668 scmd = list_entry(work_q->next,
1669 struct scsi_cmnd, eh_entry);
1671 SCSI_LOG_ERROR_RECOVERY(3,
1672 shost_printk(KERN_INFO, shost,
1673 "%s: Sending HRST\n",
1676 rtn = scsi_try_host_reset(scmd);
1677 if (rtn == SUCCESS) {
1678 list_splice_init(work_q, &check_list);
1679 } else if (rtn == FAST_IO_FAIL) {
1680 list_for_each_entry_safe(scmd, next, work_q, eh_entry) {
1681 scsi_eh_finish_cmd(scmd, done_q);
1684 SCSI_LOG_ERROR_RECOVERY(3,
1685 shost_printk(KERN_INFO, shost,
1686 "%s: HRST failed\n",
1690 return scsi_eh_test_devices(&check_list, work_q, done_q, 1);
1694 * scsi_eh_offline_sdevs - offline scsi devices that fail to recover
1695 * @work_q: &list_head for pending commands.
1696 * @done_q: &list_head for processed commands.
1698 static void scsi_eh_offline_sdevs(struct list_head *work_q,
1699 struct list_head *done_q)
1701 struct scsi_cmnd *scmd, *next;
1702 struct scsi_device *sdev;
1704 list_for_each_entry_safe(scmd, next, work_q, eh_entry) {
1705 sdev_printk(KERN_INFO, scmd->device, "Device offlined - "
1706 "not ready after error recovery\n");
1707 sdev = scmd->device;
1709 mutex_lock(&sdev->state_mutex);
1710 scsi_device_set_state(sdev, SDEV_OFFLINE);
1711 mutex_unlock(&sdev->state_mutex);
1713 scsi_eh_finish_cmd(scmd, done_q);
1719 * scsi_noretry_cmd - determine if command should be failed fast
1720 * @scmd: SCSI cmd to examine.
1722 int scsi_noretry_cmd(struct scsi_cmnd *scmd)
1724 switch (host_byte(scmd->result)) {
1730 return (scmd->request->cmd_flags & REQ_FAILFAST_TRANSPORT);
1732 return (scmd->request->cmd_flags & REQ_FAILFAST_DEV);
1734 if (msg_byte(scmd->result) == COMMAND_COMPLETE &&
1735 status_byte(scmd->result) == RESERVATION_CONFLICT)
1738 case DID_SOFT_ERROR:
1739 return (scmd->request->cmd_flags & REQ_FAILFAST_DRIVER);
1742 if (status_byte(scmd->result) != CHECK_CONDITION)
1747 * assume caller has checked sense and determined
1748 * the check condition was retryable.
1750 if (scmd->request->cmd_flags & REQ_FAILFAST_DEV ||
1751 blk_rq_is_passthrough(scmd->request))
1758 * scsi_decide_disposition - Disposition a cmd on return from LLD.
1759 * @scmd: SCSI cmd to examine.
1762 * This is *only* called when we are examining the status after sending
1763 * out the actual data command. any commands that are queued for error
1764 * recovery (e.g. test_unit_ready) do *not* come through here.
1766 * When this routine returns failed, it means the error handler thread
1767 * is woken. In cases where the error code indicates an error that
1768 * doesn't require the error handler read (i.e. we don't need to
1769 * abort/reset), this function should return SUCCESS.
1771 int scsi_decide_disposition(struct scsi_cmnd *scmd)
1776 * if the device is offline, then we clearly just pass the result back
1777 * up to the top level.
1779 if (!scsi_device_online(scmd->device)) {
1780 SCSI_LOG_ERROR_RECOVERY(5, scmd_printk(KERN_INFO, scmd,
1781 "%s: device offline - report as SUCCESS\n", __func__));
1786 * first check the host byte, to see if there is anything in there
1787 * that would indicate what we need to do.
1789 switch (host_byte(scmd->result)) {
1790 case DID_PASSTHROUGH:
1792 * no matter what, pass this through to the upper layer.
1793 * nuke this special code so that it looks like we are saying
1796 scmd->result &= 0xff00ffff;
1800 * looks good. drop through, and check the next byte.
1804 if (scmd->eh_eflags & SCSI_EH_ABORT_SCHEDULED) {
1805 set_host_byte(scmd, DID_TIME_OUT);
1809 case DID_NO_CONNECT:
1810 case DID_BAD_TARGET:
1812 * note - this means that we just report the status back
1813 * to the top level driver, not that we actually think
1814 * that it indicates SUCCESS.
1817 case DID_SOFT_ERROR:
1819 * when the low level driver returns did_soft_error,
1820 * it is responsible for keeping an internal retry counter
1821 * in order to avoid endless loops (db)
1828 return ADD_TO_MLQUEUE;
1829 case DID_TRANSPORT_DISRUPTED:
1831 * LLD/transport was disrupted during processing of the IO.
1832 * The transport class is now blocked/blocking,
1833 * and the transport will decide what to do with the IO
1834 * based on its timers and recovery capablilities if
1835 * there are enough retries.
1838 case DID_TRANSPORT_FAILFAST:
1840 * The transport decided to failfast the IO (most likely
1841 * the fast io fail tmo fired), so send IO directly upwards.
1845 if (msg_byte(scmd->result) == COMMAND_COMPLETE &&
1846 status_byte(scmd->result) == RESERVATION_CONFLICT)
1848 * execute reservation conflict processing code
1858 * when we scan the bus, we get timeout messages for
1859 * these commands if there is no device available.
1860 * other hosts report did_no_connect for the same thing.
1862 if ((scmd->cmnd[0] == TEST_UNIT_READY ||
1863 scmd->cmnd[0] == INQUIRY)) {
1875 * next, check the message byte.
1877 if (msg_byte(scmd->result) != COMMAND_COMPLETE)
1881 * check the status byte to see if this indicates anything special.
1883 switch (status_byte(scmd->result)) {
1885 scsi_handle_queue_full(scmd->device);
1887 * the case of trying to send too many commands to a
1888 * tagged queueing device.
1893 * device can't talk to us at the moment. Should only
1894 * occur (SAM-3) when the task queue is empty, so will cause
1895 * the empty queue handling to trigger a stall in the
1898 return ADD_TO_MLQUEUE;
1900 if (scmd->cmnd[0] == REPORT_LUNS)
1901 scmd->device->sdev_target->expecting_lun_change = 0;
1902 scsi_handle_queue_ramp_up(scmd->device);
1904 case COMMAND_TERMINATED:
1908 case CHECK_CONDITION:
1909 rtn = scsi_check_sense(scmd);
1910 if (rtn == NEEDS_RETRY)
1912 /* if rtn == FAILED, we have no sense information;
1913 * returning FAILED will wake the error handler thread
1914 * to collect the sense and redo the decide
1917 case CONDITION_GOOD:
1918 case INTERMEDIATE_GOOD:
1919 case INTERMEDIATE_C_GOOD:
1922 * who knows? FIXME(eric)
1926 case RESERVATION_CONFLICT:
1927 sdev_printk(KERN_INFO, scmd->device,
1928 "reservation conflict\n");
1929 set_host_byte(scmd, DID_NEXUS_FAILURE);
1930 return SUCCESS; /* causes immediate i/o error */
1938 /* we requeue for retry because the error was retryable, and
1939 * the request was not marked fast fail. Note that above,
1940 * even if the request is marked fast fail, we still requeue
1941 * for queue congestion conditions (QUEUE_FULL or BUSY) */
1942 if ((++scmd->retries) <= scmd->allowed
1943 && !scsi_noretry_cmd(scmd)) {
1947 * no more retries - report this one back to upper level.
1953 static void eh_lock_door_done(struct request *req, blk_status_t status)
1955 blk_put_request(req);
1959 * scsi_eh_lock_door - Prevent medium removal for the specified device
1960 * @sdev: SCSI device to prevent medium removal
1963 * We must be called from process context.
1966 * We queue up an asynchronous "ALLOW MEDIUM REMOVAL" request on the
1967 * head of the devices request queue, and continue.
1969 static void scsi_eh_lock_door(struct scsi_device *sdev)
1971 struct request *req;
1972 struct scsi_request *rq;
1974 req = blk_get_request(sdev->request_queue, REQ_OP_SCSI_IN, 0);
1979 rq->cmd[0] = ALLOW_MEDIUM_REMOVAL;
1983 rq->cmd[4] = SCSI_REMOVAL_PREVENT;
1985 rq->cmd_len = COMMAND_SIZE(rq->cmd[0]);
1987 req->rq_flags |= RQF_QUIET;
1988 req->timeout = 10 * HZ;
1991 blk_execute_rq_nowait(req->q, NULL, req, 1, eh_lock_door_done);
1995 * scsi_restart_operations - restart io operations to the specified host.
1996 * @shost: Host we are restarting.
1999 * When we entered the error handler, we blocked all further i/o to
2000 * this device. we need to 'reverse' this process.
2002 static void scsi_restart_operations(struct Scsi_Host *shost)
2004 struct scsi_device *sdev;
2005 unsigned long flags;
2008 * If the door was locked, we need to insert a door lock request
2009 * onto the head of the SCSI request queue for the device. There
2010 * is no point trying to lock the door of an off-line device.
2012 shost_for_each_device(sdev, shost) {
2013 if (scsi_device_online(sdev) && sdev->was_reset && sdev->locked) {
2014 scsi_eh_lock_door(sdev);
2015 sdev->was_reset = 0;
2020 * next free up anything directly waiting upon the host. this
2021 * will be requests for character device operations, and also for
2022 * ioctls to queued block devices.
2024 SCSI_LOG_ERROR_RECOVERY(3,
2025 shost_printk(KERN_INFO, shost, "waking up host to restart\n"));
2027 spin_lock_irqsave(shost->host_lock, flags);
2028 if (scsi_host_set_state(shost, SHOST_RUNNING))
2029 if (scsi_host_set_state(shost, SHOST_CANCEL))
2030 BUG_ON(scsi_host_set_state(shost, SHOST_DEL));
2031 spin_unlock_irqrestore(shost->host_lock, flags);
2033 wake_up(&shost->host_wait);
2036 * finally we need to re-initiate requests that may be pending. we will
2037 * have had everything blocked while error handling is taking place, and
2038 * now that error recovery is done, we will need to ensure that these
2039 * requests are started.
2041 scsi_run_host_queues(shost);
2044 * if eh is active and host_eh_scheduled is pending we need to re-run
2045 * recovery. we do this check after scsi_run_host_queues() to allow
2046 * everything pent up since the last eh run a chance to make forward
2047 * progress before we sync again. Either we'll immediately re-run
2048 * recovery or scsi_device_unbusy() will wake us again when these
2049 * pending commands complete.
2051 spin_lock_irqsave(shost->host_lock, flags);
2052 if (shost->host_eh_scheduled)
2053 if (scsi_host_set_state(shost, SHOST_RECOVERY))
2054 WARN_ON(scsi_host_set_state(shost, SHOST_CANCEL_RECOVERY));
2055 spin_unlock_irqrestore(shost->host_lock, flags);
2059 * scsi_eh_ready_devs - check device ready state and recover if not.
2060 * @shost: host to be recovered.
2061 * @work_q: &list_head for pending commands.
2062 * @done_q: &list_head for processed commands.
2064 void scsi_eh_ready_devs(struct Scsi_Host *shost,
2065 struct list_head *work_q,
2066 struct list_head *done_q)
2068 if (!scsi_eh_stu(shost, work_q, done_q))
2069 if (!scsi_eh_bus_device_reset(shost, work_q, done_q))
2070 if (!scsi_eh_target_reset(shost, work_q, done_q))
2071 if (!scsi_eh_bus_reset(shost, work_q, done_q))
2072 if (!scsi_eh_host_reset(shost, work_q, done_q))
2073 scsi_eh_offline_sdevs(work_q,
2076 EXPORT_SYMBOL_GPL(scsi_eh_ready_devs);
2079 * scsi_eh_flush_done_q - finish processed commands or retry them.
2080 * @done_q: list_head of processed commands.
2082 void scsi_eh_flush_done_q(struct list_head *done_q)
2084 struct scsi_cmnd *scmd, *next;
2086 list_for_each_entry_safe(scmd, next, done_q, eh_entry) {
2087 list_del_init(&scmd->eh_entry);
2088 if (scsi_device_online(scmd->device) &&
2089 !scsi_noretry_cmd(scmd) &&
2090 (++scmd->retries <= scmd->allowed)) {
2091 SCSI_LOG_ERROR_RECOVERY(3,
2092 scmd_printk(KERN_INFO, scmd,
2093 "%s: flush retry cmd\n",
2095 scsi_queue_insert(scmd, SCSI_MLQUEUE_EH_RETRY);
2098 * If just we got sense for the device (called
2099 * scsi_eh_get_sense), scmd->result is already
2100 * set, do not set DRIVER_TIMEOUT.
2103 scmd->result |= (DRIVER_TIMEOUT << 24);
2104 SCSI_LOG_ERROR_RECOVERY(3,
2105 scmd_printk(KERN_INFO, scmd,
2106 "%s: flush finish cmd\n",
2108 scsi_finish_command(scmd);
2112 EXPORT_SYMBOL(scsi_eh_flush_done_q);
2115 * scsi_unjam_host - Attempt to fix a host which has a cmd that failed.
2116 * @shost: Host to unjam.
2119 * When we come in here, we *know* that all commands on the bus have
2120 * either completed, failed or timed out. we also know that no further
2121 * commands are being sent to the host, so things are relatively quiet
2122 * and we have freedom to fiddle with things as we wish.
2124 * This is only the *default* implementation. it is possible for
2125 * individual drivers to supply their own version of this function, and
2126 * if the maintainer wishes to do this, it is strongly suggested that
2127 * this function be taken as a template and modified. this function
2128 * was designed to correctly handle problems for about 95% of the
2129 * different cases out there, and it should always provide at least a
2130 * reasonable amount of error recovery.
2132 * Any command marked 'failed' or 'timeout' must eventually have
2133 * scsi_finish_cmd() called for it. we do all of the retry stuff
2134 * here, so when we restart the host after we return it should have an
2137 static void scsi_unjam_host(struct Scsi_Host *shost)
2139 unsigned long flags;
2140 LIST_HEAD(eh_work_q);
2141 LIST_HEAD(eh_done_q);
2143 spin_lock_irqsave(shost->host_lock, flags);
2144 list_splice_init(&shost->eh_cmd_q, &eh_work_q);
2145 spin_unlock_irqrestore(shost->host_lock, flags);
2147 SCSI_LOG_ERROR_RECOVERY(1, scsi_eh_prt_fail_stats(shost, &eh_work_q));
2149 if (!scsi_eh_get_sense(&eh_work_q, &eh_done_q))
2150 scsi_eh_ready_devs(shost, &eh_work_q, &eh_done_q);
2152 spin_lock_irqsave(shost->host_lock, flags);
2153 if (shost->eh_deadline != -1)
2154 shost->last_reset = 0;
2155 spin_unlock_irqrestore(shost->host_lock, flags);
2156 scsi_eh_flush_done_q(&eh_done_q);
2160 * scsi_error_handler - SCSI error handler thread
2161 * @data: Host for which we are running.
2164 * This is the main error handling loop. This is run as a kernel thread
2165 * for every SCSI host and handles all error handling activity.
2167 int scsi_error_handler(void *data)
2169 struct Scsi_Host *shost = data;
2172 * We use TASK_INTERRUPTIBLE so that the thread is not
2173 * counted against the load average as a running process.
2174 * We never actually get interrupted because kthread_run
2175 * disables signal delivery for the created thread.
2179 * The sequence in kthread_stop() sets the stop flag first
2180 * then wakes the process. To avoid missed wakeups, the task
2181 * should always be in a non running state before the stop
2184 set_current_state(TASK_INTERRUPTIBLE);
2185 if (kthread_should_stop())
2188 if ((shost->host_failed == 0 && shost->host_eh_scheduled == 0) ||
2189 shost->host_failed != scsi_host_busy(shost)) {
2190 SCSI_LOG_ERROR_RECOVERY(1,
2191 shost_printk(KERN_INFO, shost,
2192 "scsi_eh_%d: sleeping\n",
2198 __set_current_state(TASK_RUNNING);
2199 SCSI_LOG_ERROR_RECOVERY(1,
2200 shost_printk(KERN_INFO, shost,
2201 "scsi_eh_%d: waking up %d/%d/%d\n",
2202 shost->host_no, shost->host_eh_scheduled,
2204 scsi_host_busy(shost)));
2207 * We have a host that is failing for some reason. Figure out
2208 * what we need to do to get it up and online again (if we can).
2209 * If we fail, we end up taking the thing offline.
2211 if (!shost->eh_noresume && scsi_autopm_get_host(shost) != 0) {
2212 SCSI_LOG_ERROR_RECOVERY(1,
2213 shost_printk(KERN_ERR, shost,
2214 "scsi_eh_%d: unable to autoresume\n",
2219 if (shost->transportt->eh_strategy_handler)
2220 shost->transportt->eh_strategy_handler(shost);
2222 scsi_unjam_host(shost);
2224 /* All scmds have been handled */
2225 shost->host_failed = 0;
2228 * Note - if the above fails completely, the action is to take
2229 * individual devices offline and flush the queue of any
2230 * outstanding requests that may have been pending. When we
2231 * restart, we restart any I/O to any other devices on the bus
2232 * which are still online.
2234 scsi_restart_operations(shost);
2235 if (!shost->eh_noresume)
2236 scsi_autopm_put_host(shost);
2238 __set_current_state(TASK_RUNNING);
2240 SCSI_LOG_ERROR_RECOVERY(1,
2241 shost_printk(KERN_INFO, shost,
2242 "Error handler scsi_eh_%d exiting\n",
2244 shost->ehandler = NULL;
2249 * Function: scsi_report_bus_reset()
2251 * Purpose: Utility function used by low-level drivers to report that
2252 * they have observed a bus reset on the bus being handled.
2254 * Arguments: shost - Host in question
2255 * channel - channel on which reset was observed.
2259 * Lock status: Host lock must be held.
2261 * Notes: This only needs to be called if the reset is one which
2262 * originates from an unknown location. Resets originated
2263 * by the mid-level itself don't need to call this, but there
2264 * should be no harm.
2266 * The main purpose of this is to make sure that a CHECK_CONDITION
2267 * is properly treated.
2269 void scsi_report_bus_reset(struct Scsi_Host *shost, int channel)
2271 struct scsi_device *sdev;
2273 __shost_for_each_device(sdev, shost) {
2274 if (channel == sdev_channel(sdev))
2275 __scsi_report_device_reset(sdev, NULL);
2278 EXPORT_SYMBOL(scsi_report_bus_reset);
2281 * Function: scsi_report_device_reset()
2283 * Purpose: Utility function used by low-level drivers to report that
2284 * they have observed a device reset on the device being handled.
2286 * Arguments: shost - Host in question
2287 * channel - channel on which reset was observed
2288 * target - target on which reset was observed
2292 * Lock status: Host lock must be held
2294 * Notes: This only needs to be called if the reset is one which
2295 * originates from an unknown location. Resets originated
2296 * by the mid-level itself don't need to call this, but there
2297 * should be no harm.
2299 * The main purpose of this is to make sure that a CHECK_CONDITION
2300 * is properly treated.
2302 void scsi_report_device_reset(struct Scsi_Host *shost, int channel, int target)
2304 struct scsi_device *sdev;
2306 __shost_for_each_device(sdev, shost) {
2307 if (channel == sdev_channel(sdev) &&
2308 target == sdev_id(sdev))
2309 __scsi_report_device_reset(sdev, NULL);
2312 EXPORT_SYMBOL(scsi_report_device_reset);
2315 scsi_reset_provider_done_command(struct scsi_cmnd *scmd)
2320 * scsi_ioctl_reset: explicitly reset a host/bus/target/device
2321 * @dev: scsi_device to operate on
2322 * @arg: reset type (see sg.h)
2325 scsi_ioctl_reset(struct scsi_device *dev, int __user *arg)
2327 struct scsi_cmnd *scmd;
2328 struct Scsi_Host *shost = dev->host;
2330 unsigned long flags;
2331 int error = 0, rtn, val;
2333 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2336 error = get_user(val, arg);
2340 if (scsi_autopm_get_host(shost) < 0)
2344 rq = kzalloc(sizeof(struct request) + sizeof(struct scsi_cmnd) +
2345 shost->hostt->cmd_size, GFP_KERNEL);
2347 goto out_put_autopm_host;
2348 blk_rq_init(NULL, rq);
2350 scmd = (struct scsi_cmnd *)(rq + 1);
2351 scsi_init_command(dev, scmd);
2353 scmd->cmnd = scsi_req(rq)->cmd;
2355 scmd->scsi_done = scsi_reset_provider_done_command;
2356 memset(&scmd->sdb, 0, sizeof(scmd->sdb));
2360 scmd->sc_data_direction = DMA_BIDIRECTIONAL;
2362 spin_lock_irqsave(shost->host_lock, flags);
2363 shost->tmf_in_progress = 1;
2364 spin_unlock_irqrestore(shost->host_lock, flags);
2366 switch (val & ~SG_SCSI_RESET_NO_ESCALATE) {
2367 case SG_SCSI_RESET_NOTHING:
2370 case SG_SCSI_RESET_DEVICE:
2371 rtn = scsi_try_bus_device_reset(scmd);
2372 if (rtn == SUCCESS || (val & SG_SCSI_RESET_NO_ESCALATE))
2375 case SG_SCSI_RESET_TARGET:
2376 rtn = scsi_try_target_reset(scmd);
2377 if (rtn == SUCCESS || (val & SG_SCSI_RESET_NO_ESCALATE))
2380 case SG_SCSI_RESET_BUS:
2381 rtn = scsi_try_bus_reset(scmd);
2382 if (rtn == SUCCESS || (val & SG_SCSI_RESET_NO_ESCALATE))
2385 case SG_SCSI_RESET_HOST:
2386 rtn = scsi_try_host_reset(scmd);
2395 error = (rtn == SUCCESS) ? 0 : -EIO;
2397 spin_lock_irqsave(shost->host_lock, flags);
2398 shost->tmf_in_progress = 0;
2399 spin_unlock_irqrestore(shost->host_lock, flags);
2402 * be sure to wake up anyone who was sleeping or had their queue
2403 * suspended while we performed the TMF.
2405 SCSI_LOG_ERROR_RECOVERY(3,
2406 shost_printk(KERN_INFO, shost,
2407 "waking up host to restart after TMF\n"));
2409 wake_up(&shost->host_wait);
2410 scsi_run_host_queues(shost);
2412 scsi_put_command(scmd);
2415 out_put_autopm_host:
2416 scsi_autopm_put_host(shost);
2420 bool scsi_command_normalize_sense(const struct scsi_cmnd *cmd,
2421 struct scsi_sense_hdr *sshdr)
2423 return scsi_normalize_sense(cmd->sense_buffer,
2424 SCSI_SENSE_BUFFERSIZE, sshdr);
2426 EXPORT_SYMBOL(scsi_command_normalize_sense);
2429 * scsi_get_sense_info_fld - get information field from sense data (either fixed or descriptor format)
2430 * @sense_buffer: byte array of sense data
2431 * @sb_len: number of valid bytes in sense_buffer
2432 * @info_out: pointer to 64 integer where 8 or 4 byte information
2433 * field will be placed if found.
2436 * true if information field found, false if not found.
2438 bool scsi_get_sense_info_fld(const u8 *sense_buffer, int sb_len,
2445 switch (sense_buffer[0] & 0x7f) {
2448 if (sense_buffer[0] & 0x80) {
2449 *info_out = get_unaligned_be32(&sense_buffer[3]);
2455 ucp = scsi_sense_desc_find(sense_buffer, sb_len,
2457 if (ucp && (0xa == ucp[1])) {
2458 *info_out = get_unaligned_be64(&ucp[4]);
2466 EXPORT_SYMBOL(scsi_get_sense_info_fld);