2 * scsi_error.c Copyright (C) 1997 Eric Youngdale
4 * SCSI error/timeout handling
5 * Initial versions: Eric Youngdale. Based upon conversations with
6 * Leonard Zubkoff and David Miller at Linux Expo,
7 * ideas originating from all over the place.
9 * Restructured scsi_unjam_host and associated functions.
10 * September 04, 2002 Mike Anderson (andmike@us.ibm.com)
12 * Forward port of Russell King's (rmk@arm.linux.org.uk) changes and
14 * September 30, 2002 Mike Anderson (andmike@us.ibm.com)
17 #include <linux/module.h>
18 #include <linux/sched.h>
19 #include <linux/gfp.h>
20 #include <linux/timer.h>
21 #include <linux/string.h>
22 #include <linux/kernel.h>
23 #include <linux/freezer.h>
24 #include <linux/kthread.h>
25 #include <linux/interrupt.h>
26 #include <linux/blkdev.h>
27 #include <linux/delay.h>
28 #include <linux/jiffies.h>
30 #include <scsi/scsi.h>
31 #include <scsi/scsi_cmnd.h>
32 #include <scsi/scsi_dbg.h>
33 #include <scsi/scsi_device.h>
34 #include <scsi/scsi_driver.h>
35 #include <scsi/scsi_eh.h>
36 #include <scsi/scsi_transport.h>
37 #include <scsi/scsi_host.h>
38 #include <scsi/scsi_ioctl.h>
40 #include "scsi_priv.h"
41 #include "scsi_logging.h"
42 #include "scsi_transport_api.h"
44 #include <trace/events/scsi.h>
46 static void scsi_eh_done(struct scsi_cmnd *scmd);
49 * These should *probably* be handled by the host itself.
50 * Since it is allowed to sleep, it probably should.
52 #define BUS_RESET_SETTLE_TIME (10)
53 #define HOST_RESET_SETTLE_TIME (10)
55 static int scsi_eh_try_stu(struct scsi_cmnd *scmd);
56 static int scsi_try_to_abort_cmd(struct scsi_host_template *,
59 /* called with shost->host_lock held */
60 void scsi_eh_wakeup(struct Scsi_Host *shost)
62 if (atomic_read(&shost->host_busy) == shost->host_failed) {
63 trace_scsi_eh_wakeup(shost);
64 wake_up_process(shost->ehandler);
65 SCSI_LOG_ERROR_RECOVERY(5, shost_printk(KERN_INFO, shost,
66 "Waking error handler thread\n"));
71 * scsi_schedule_eh - schedule EH for SCSI host
72 * @shost: SCSI host to invoke error handling on.
74 * Schedule SCSI EH without scmd.
76 void scsi_schedule_eh(struct Scsi_Host *shost)
80 spin_lock_irqsave(shost->host_lock, flags);
82 if (scsi_host_set_state(shost, SHOST_RECOVERY) == 0 ||
83 scsi_host_set_state(shost, SHOST_CANCEL_RECOVERY) == 0) {
84 shost->host_eh_scheduled++;
85 scsi_eh_wakeup(shost);
88 spin_unlock_irqrestore(shost->host_lock, flags);
90 EXPORT_SYMBOL_GPL(scsi_schedule_eh);
92 static int scsi_host_eh_past_deadline(struct Scsi_Host *shost)
94 if (!shost->last_reset || shost->eh_deadline == -1)
98 * 32bit accesses are guaranteed to be atomic
99 * (on all supported architectures), so instead
100 * of using a spinlock we can as well double check
101 * if eh_deadline has been set to 'off' during the
104 if (time_before(jiffies, shost->last_reset + shost->eh_deadline) &&
105 shost->eh_deadline > -1)
112 * scmd_eh_abort_handler - Handle command aborts
113 * @work: command to be aborted.
116 scmd_eh_abort_handler(struct work_struct *work)
118 struct scsi_cmnd *scmd =
119 container_of(work, struct scsi_cmnd, abort_work.work);
120 struct scsi_device *sdev = scmd->device;
123 if (scsi_host_eh_past_deadline(sdev->host)) {
124 SCSI_LOG_ERROR_RECOVERY(3,
125 scmd_printk(KERN_INFO, scmd,
126 "scmd %p eh timeout, not aborting\n",
129 SCSI_LOG_ERROR_RECOVERY(3,
130 scmd_printk(KERN_INFO, scmd,
131 "aborting command %p\n", scmd));
132 rtn = scsi_try_to_abort_cmd(sdev->host->hostt, scmd);
133 if (rtn == SUCCESS) {
134 set_host_byte(scmd, DID_TIME_OUT);
135 if (scsi_host_eh_past_deadline(sdev->host)) {
136 SCSI_LOG_ERROR_RECOVERY(3,
137 scmd_printk(KERN_INFO, scmd,
138 "scmd %p eh timeout, "
139 "not retrying aborted "
141 } else if (!scsi_noretry_cmd(scmd) &&
142 (++scmd->retries <= scmd->allowed)) {
143 SCSI_LOG_ERROR_RECOVERY(3,
144 scmd_printk(KERN_WARNING, scmd,
146 "aborted command\n", scmd));
147 scsi_queue_insert(scmd, SCSI_MLQUEUE_EH_RETRY);
150 SCSI_LOG_ERROR_RECOVERY(3,
151 scmd_printk(KERN_WARNING, scmd,
153 "aborted command\n", scmd));
154 scsi_finish_command(scmd);
158 SCSI_LOG_ERROR_RECOVERY(3,
159 scmd_printk(KERN_INFO, scmd,
160 "scmd %p abort failed, rtn %d\n",
165 if (!scsi_eh_scmd_add(scmd, 0)) {
166 SCSI_LOG_ERROR_RECOVERY(3,
167 scmd_printk(KERN_WARNING, scmd,
169 "aborted command\n", scmd));
170 set_host_byte(scmd, DID_TIME_OUT);
171 scsi_finish_command(scmd);
176 * scsi_abort_command - schedule a command abort
177 * @scmd: scmd to abort.
179 * We only need to abort commands after a command timeout
182 scsi_abort_command(struct scsi_cmnd *scmd)
184 struct scsi_device *sdev = scmd->device;
185 struct Scsi_Host *shost = sdev->host;
188 if (scmd->eh_eflags & SCSI_EH_ABORT_SCHEDULED) {
190 * Retry after abort failed, escalate to next level.
192 scmd->eh_eflags &= ~SCSI_EH_ABORT_SCHEDULED;
193 SCSI_LOG_ERROR_RECOVERY(3,
194 scmd_printk(KERN_INFO, scmd,
195 "scmd %p previous abort failed\n", scmd));
196 BUG_ON(delayed_work_pending(&scmd->abort_work));
201 * Do not try a command abort if
202 * SCSI EH has already started.
204 spin_lock_irqsave(shost->host_lock, flags);
205 if (scsi_host_in_recovery(shost)) {
206 spin_unlock_irqrestore(shost->host_lock, flags);
207 SCSI_LOG_ERROR_RECOVERY(3,
208 scmd_printk(KERN_INFO, scmd,
209 "scmd %p not aborting, host in recovery\n",
214 if (shost->eh_deadline != -1 && !shost->last_reset)
215 shost->last_reset = jiffies;
216 spin_unlock_irqrestore(shost->host_lock, flags);
218 scmd->eh_eflags |= SCSI_EH_ABORT_SCHEDULED;
219 SCSI_LOG_ERROR_RECOVERY(3,
220 scmd_printk(KERN_INFO, scmd,
221 "scmd %p abort scheduled\n", scmd));
222 queue_delayed_work(shost->tmf_work_q, &scmd->abort_work, HZ / 100);
227 * scsi_eh_scmd_add - add scsi cmd to error handling.
228 * @scmd: scmd to run eh on.
229 * @eh_flag: optional SCSI_EH flag.
234 int scsi_eh_scmd_add(struct scsi_cmnd *scmd, int eh_flag)
236 struct Scsi_Host *shost = scmd->device->host;
240 if (!shost->ehandler)
243 spin_lock_irqsave(shost->host_lock, flags);
244 if (scsi_host_set_state(shost, SHOST_RECOVERY))
245 if (scsi_host_set_state(shost, SHOST_CANCEL_RECOVERY))
248 if (shost->eh_deadline != -1 && !shost->last_reset)
249 shost->last_reset = jiffies;
252 if (scmd->eh_eflags & SCSI_EH_ABORT_SCHEDULED)
253 eh_flag &= ~SCSI_EH_CANCEL_CMD;
254 scmd->eh_eflags |= eh_flag;
255 list_add_tail(&scmd->eh_entry, &shost->eh_cmd_q);
256 shost->host_failed++;
257 scsi_eh_wakeup(shost);
259 spin_unlock_irqrestore(shost->host_lock, flags);
264 * scsi_times_out - Timeout function for normal scsi commands.
265 * @req: request that is timing out.
268 * We do not need to lock this. There is the potential for a race
269 * only in that the normal completion handling might run, but if the
270 * normal completion function determines that the timer has already
271 * fired, then it mustn't do anything.
273 enum blk_eh_timer_return scsi_times_out(struct request *req)
275 struct scsi_cmnd *scmd = req->special;
276 enum blk_eh_timer_return rtn = BLK_EH_NOT_HANDLED;
277 struct Scsi_Host *host = scmd->device->host;
279 trace_scsi_dispatch_cmd_timeout(scmd);
280 scsi_log_completion(scmd, TIMEOUT_ERROR);
282 if (host->eh_deadline != -1 && !host->last_reset)
283 host->last_reset = jiffies;
285 if (host->transportt->eh_timed_out)
286 rtn = host->transportt->eh_timed_out(scmd);
287 else if (host->hostt->eh_timed_out)
288 rtn = host->hostt->eh_timed_out(scmd);
290 if (rtn == BLK_EH_NOT_HANDLED) {
291 if (!host->hostt->no_async_abort &&
292 scsi_abort_command(scmd) == SUCCESS)
293 return BLK_EH_NOT_HANDLED;
295 set_host_byte(scmd, DID_TIME_OUT);
296 if (!scsi_eh_scmd_add(scmd, SCSI_EH_CANCEL_CMD))
297 rtn = BLK_EH_HANDLED;
304 * scsi_block_when_processing_errors - Prevent cmds from being queued.
305 * @sdev: Device on which we are performing recovery.
308 * We block until the host is out of error recovery, and then check to
309 * see whether the host or the device is offline.
312 * 0 when dev was taken offline by error recovery. 1 OK to proceed.
314 int scsi_block_when_processing_errors(struct scsi_device *sdev)
318 wait_event(sdev->host->host_wait, !scsi_host_in_recovery(sdev->host));
320 online = scsi_device_online(sdev);
322 SCSI_LOG_ERROR_RECOVERY(5, sdev_printk(KERN_INFO, sdev,
323 "%s: rtn: %d\n", __func__, online));
327 EXPORT_SYMBOL(scsi_block_when_processing_errors);
329 #ifdef CONFIG_SCSI_LOGGING
331 * scsi_eh_prt_fail_stats - Log info on failures.
332 * @shost: scsi host being recovered.
333 * @work_q: Queue of scsi cmds to process.
335 static inline void scsi_eh_prt_fail_stats(struct Scsi_Host *shost,
336 struct list_head *work_q)
338 struct scsi_cmnd *scmd;
339 struct scsi_device *sdev;
340 int total_failures = 0;
343 int devices_failed = 0;
345 shost_for_each_device(sdev, shost) {
346 list_for_each_entry(scmd, work_q, eh_entry) {
347 if (scmd->device == sdev) {
349 if (scmd->eh_eflags & SCSI_EH_CANCEL_CMD)
356 if (cmd_cancel || cmd_failed) {
357 SCSI_LOG_ERROR_RECOVERY(3,
358 sdev_printk(KERN_INFO, sdev,
359 "%s: cmds failed: %d, cancel: %d\n",
360 __func__, cmd_failed,
368 SCSI_LOG_ERROR_RECOVERY(2, shost_printk(KERN_INFO, shost,
369 "Total of %d commands on %d"
370 " devices require eh work\n",
371 total_failures, devices_failed));
376 * scsi_report_lun_change - Set flag on all *other* devices on the same target
377 * to indicate that a UNIT ATTENTION is expected.
378 * @sdev: Device reporting the UNIT ATTENTION
380 static void scsi_report_lun_change(struct scsi_device *sdev)
382 sdev->sdev_target->expecting_lun_change = 1;
386 * scsi_report_sense - Examine scsi sense information and log messages for
387 * certain conditions, also issue uevents for some of them.
388 * @sdev: Device reporting the sense code
389 * @sshdr: sshdr to be examined
391 static void scsi_report_sense(struct scsi_device *sdev,
392 struct scsi_sense_hdr *sshdr)
394 enum scsi_device_event evt_type = SDEV_EVT_MAXBITS; /* i.e. none */
396 if (sshdr->sense_key == UNIT_ATTENTION) {
397 if (sshdr->asc == 0x3f && sshdr->ascq == 0x03) {
398 evt_type = SDEV_EVT_INQUIRY_CHANGE_REPORTED;
399 sdev_printk(KERN_WARNING, sdev,
400 "Inquiry data has changed");
401 } else if (sshdr->asc == 0x3f && sshdr->ascq == 0x0e) {
402 evt_type = SDEV_EVT_LUN_CHANGE_REPORTED;
403 scsi_report_lun_change(sdev);
404 sdev_printk(KERN_WARNING, sdev,
405 "Warning! Received an indication that the "
406 "LUN assignments on this target have "
407 "changed. The Linux SCSI layer does not "
408 "automatically remap LUN assignments.\n");
409 } else if (sshdr->asc == 0x3f)
410 sdev_printk(KERN_WARNING, sdev,
411 "Warning! Received an indication that the "
412 "operating parameters on this target have "
413 "changed. The Linux SCSI layer does not "
414 "automatically adjust these parameters.\n");
416 if (sshdr->asc == 0x38 && sshdr->ascq == 0x07) {
417 evt_type = SDEV_EVT_SOFT_THRESHOLD_REACHED_REPORTED;
418 sdev_printk(KERN_WARNING, sdev,
419 "Warning! Received an indication that the "
420 "LUN reached a thin provisioning soft "
424 if (sshdr->asc == 0x2a && sshdr->ascq == 0x01) {
425 evt_type = SDEV_EVT_MODE_PARAMETER_CHANGE_REPORTED;
426 sdev_printk(KERN_WARNING, sdev,
427 "Mode parameters changed");
428 } else if (sshdr->asc == 0x2a && sshdr->ascq == 0x09) {
429 evt_type = SDEV_EVT_CAPACITY_CHANGE_REPORTED;
430 sdev_printk(KERN_WARNING, sdev,
431 "Capacity data has changed");
432 } else if (sshdr->asc == 0x2a)
433 sdev_printk(KERN_WARNING, sdev,
434 "Parameters changed");
437 if (evt_type != SDEV_EVT_MAXBITS) {
438 set_bit(evt_type, sdev->pending_events);
439 schedule_work(&sdev->event_work);
444 * scsi_check_sense - Examine scsi cmd sense
445 * @scmd: Cmd to have sense checked.
448 * SUCCESS or FAILED or NEEDS_RETRY or ADD_TO_MLQUEUE
451 * When a deferred error is detected the current command has
452 * not been executed and needs retrying.
454 static int scsi_check_sense(struct scsi_cmnd *scmd)
456 struct scsi_device *sdev = scmd->device;
457 struct scsi_sense_hdr sshdr;
459 if (! scsi_command_normalize_sense(scmd, &sshdr))
460 return FAILED; /* no valid sense data */
462 scsi_report_sense(sdev, &sshdr);
464 if (scsi_sense_is_deferred(&sshdr))
467 if (sdev->scsi_dh_data && sdev->scsi_dh_data->scsi_dh &&
468 sdev->scsi_dh_data->scsi_dh->check_sense) {
471 rc = sdev->scsi_dh_data->scsi_dh->check_sense(sdev, &sshdr);
472 if (rc != SCSI_RETURN_NOT_HANDLED)
474 /* handler does not care. Drop down to default handling */
477 if (scmd->cmnd[0] == TEST_UNIT_READY && scmd->scsi_done != scsi_eh_done)
479 * nasty: for mid-layer issued TURs, we need to return the
480 * actual sense data without any recovery attempt. For eh
481 * issued ones, we need to try to recover and interpret
486 * Previous logic looked for FILEMARK, EOM or ILI which are
487 * mainly associated with tapes and returned SUCCESS.
489 if (sshdr.response_code == 0x70) {
491 if (scmd->sense_buffer[2] & 0xe0)
495 * descriptor format: look for "stream commands sense data
496 * descriptor" (see SSC-3). Assume single sense data
497 * descriptor. Ignore ILI from SBC-2 READ LONG and WRITE LONG.
499 if ((sshdr.additional_length > 3) &&
500 (scmd->sense_buffer[8] == 0x4) &&
501 (scmd->sense_buffer[11] & 0xe0))
505 switch (sshdr.sense_key) {
508 case RECOVERED_ERROR:
509 return /* soft_error */ SUCCESS;
511 case ABORTED_COMMAND:
512 if (sshdr.asc == 0x10) /* DIF */
519 * if we are expecting a cc/ua because of a bus reset that we
520 * performed, treat this just as a retry. otherwise this is
521 * information that we should pass up to the upper-level driver
522 * so that we can deal with it there.
524 if (scmd->device->expecting_cc_ua) {
526 * Because some device does not queue unit
527 * attentions correctly, we carefully check
528 * additional sense code and qualifier so as
529 * not to squash media change unit attention.
531 if (sshdr.asc != 0x28 || sshdr.ascq != 0x00) {
532 scmd->device->expecting_cc_ua = 0;
537 * we might also expect a cc/ua if another LUN on the target
538 * reported a UA with an ASC/ASCQ of 3F 0E -
539 * REPORTED LUNS DATA HAS CHANGED.
541 if (scmd->device->sdev_target->expecting_lun_change &&
542 sshdr.asc == 0x3f && sshdr.ascq == 0x0e)
545 * if the device is in the process of becoming ready, we
548 if ((sshdr.asc == 0x04) && (sshdr.ascq == 0x01))
551 * if the device is not started, we need to wake
552 * the error handler to start the motor
554 if (scmd->device->allow_restart &&
555 (sshdr.asc == 0x04) && (sshdr.ascq == 0x02))
558 * Pass the UA upwards for a determination in the completion
563 /* these are not supported */
565 if (sshdr.asc == 0x27 && sshdr.ascq == 0x07) {
566 /* Thin provisioning hard threshold reached */
567 set_host_byte(scmd, DID_ALLOC_FAILURE);
571 case VOLUME_OVERFLOW:
574 set_host_byte(scmd, DID_TARGET_FAILURE);
578 if (sshdr.asc == 0x11 || /* UNRECOVERED READ ERR */
579 sshdr.asc == 0x13 || /* AMNF DATA FIELD */
580 sshdr.asc == 0x14) { /* RECORD NOT FOUND */
581 set_host_byte(scmd, DID_MEDIUM_ERROR);
587 if (scmd->device->retry_hwerror)
588 return ADD_TO_MLQUEUE;
590 set_host_byte(scmd, DID_TARGET_FAILURE);
592 case ILLEGAL_REQUEST:
593 if (sshdr.asc == 0x20 || /* Invalid command operation code */
594 sshdr.asc == 0x21 || /* Logical block address out of range */
595 sshdr.asc == 0x24 || /* Invalid field in cdb */
596 sshdr.asc == 0x26) { /* Parameter value invalid */
597 set_host_byte(scmd, DID_TARGET_FAILURE);
606 static void scsi_handle_queue_ramp_up(struct scsi_device *sdev)
608 struct scsi_host_template *sht = sdev->host->hostt;
609 struct scsi_device *tmp_sdev;
611 if (!sht->change_queue_depth ||
612 sdev->queue_depth >= sdev->max_queue_depth)
615 if (time_before(jiffies,
616 sdev->last_queue_ramp_up + sdev->queue_ramp_up_period))
619 if (time_before(jiffies,
620 sdev->last_queue_full_time + sdev->queue_ramp_up_period))
624 * Walk all devices of a target and do
627 shost_for_each_device(tmp_sdev, sdev->host) {
628 if (tmp_sdev->channel != sdev->channel ||
629 tmp_sdev->id != sdev->id ||
630 tmp_sdev->queue_depth == sdev->max_queue_depth)
633 * call back into LLD to increase queue_depth by one
634 * with ramp up reason code.
636 sht->change_queue_depth(tmp_sdev, tmp_sdev->queue_depth + 1,
637 SCSI_QDEPTH_RAMP_UP);
638 sdev->last_queue_ramp_up = jiffies;
642 static void scsi_handle_queue_full(struct scsi_device *sdev)
644 struct scsi_host_template *sht = sdev->host->hostt;
645 struct scsi_device *tmp_sdev;
647 if (!sht->change_queue_depth)
650 shost_for_each_device(tmp_sdev, sdev->host) {
651 if (tmp_sdev->channel != sdev->channel ||
652 tmp_sdev->id != sdev->id)
655 * We do not know the number of commands that were at
656 * the device when we got the queue full so we start
657 * from the highest possible value and work our way down.
659 sht->change_queue_depth(tmp_sdev, tmp_sdev->queue_depth - 1,
665 * scsi_eh_completed_normally - Disposition a eh cmd on return from LLD.
666 * @scmd: SCSI cmd to examine.
669 * This is *only* called when we are examining the status of commands
670 * queued during error recovery. the main difference here is that we
671 * don't allow for the possibility of retries here, and we are a lot
672 * more restrictive about what we consider acceptable.
674 static int scsi_eh_completed_normally(struct scsi_cmnd *scmd)
677 * first check the host byte, to see if there is anything in there
678 * that would indicate what we need to do.
680 if (host_byte(scmd->result) == DID_RESET) {
682 * rats. we are already in the error handler, so we now
683 * get to try and figure out what to do next. if the sense
684 * is valid, we have a pretty good idea of what to do.
685 * if not, we mark it as FAILED.
687 return scsi_check_sense(scmd);
689 if (host_byte(scmd->result) != DID_OK)
693 * next, check the message byte.
695 if (msg_byte(scmd->result) != COMMAND_COMPLETE)
699 * now, check the status byte to see if this indicates
702 switch (status_byte(scmd->result)) {
704 scsi_handle_queue_ramp_up(scmd->device);
705 case COMMAND_TERMINATED:
707 case CHECK_CONDITION:
708 return scsi_check_sense(scmd);
710 case INTERMEDIATE_GOOD:
711 case INTERMEDIATE_C_GOOD:
713 * who knows? FIXME(eric)
716 case RESERVATION_CONFLICT:
717 if (scmd->cmnd[0] == TEST_UNIT_READY)
718 /* it is a success, we probed the device and
721 /* otherwise, we failed to send the command */
724 scsi_handle_queue_full(scmd->device);
735 * scsi_eh_done - Completion function for error handling.
736 * @scmd: Cmd that is done.
738 static void scsi_eh_done(struct scsi_cmnd *scmd)
740 struct completion *eh_action;
742 SCSI_LOG_ERROR_RECOVERY(3, scmd_printk(KERN_INFO, scmd,
743 "%s scmd: %p result: %x\n",
744 __func__, scmd, scmd->result));
746 eh_action = scmd->device->host->eh_action;
752 * scsi_try_host_reset - ask host adapter to reset itself
753 * @scmd: SCSI cmd to send host reset.
755 static int scsi_try_host_reset(struct scsi_cmnd *scmd)
759 struct Scsi_Host *host = scmd->device->host;
760 struct scsi_host_template *hostt = host->hostt;
762 SCSI_LOG_ERROR_RECOVERY(3,
763 shost_printk(KERN_INFO, host, "Snd Host RST\n"));
765 if (!hostt->eh_host_reset_handler)
768 rtn = hostt->eh_host_reset_handler(scmd);
770 if (rtn == SUCCESS) {
771 if (!hostt->skip_settle_delay)
772 ssleep(HOST_RESET_SETTLE_TIME);
773 spin_lock_irqsave(host->host_lock, flags);
774 scsi_report_bus_reset(host, scmd_channel(scmd));
775 spin_unlock_irqrestore(host->host_lock, flags);
782 * scsi_try_bus_reset - ask host to perform a bus reset
783 * @scmd: SCSI cmd to send bus reset.
785 static int scsi_try_bus_reset(struct scsi_cmnd *scmd)
789 struct Scsi_Host *host = scmd->device->host;
790 struct scsi_host_template *hostt = host->hostt;
792 SCSI_LOG_ERROR_RECOVERY(3, scmd_printk(KERN_INFO, scmd,
793 "%s: Snd Bus RST\n", __func__));
795 if (!hostt->eh_bus_reset_handler)
798 rtn = hostt->eh_bus_reset_handler(scmd);
800 if (rtn == SUCCESS) {
801 if (!hostt->skip_settle_delay)
802 ssleep(BUS_RESET_SETTLE_TIME);
803 spin_lock_irqsave(host->host_lock, flags);
804 scsi_report_bus_reset(host, scmd_channel(scmd));
805 spin_unlock_irqrestore(host->host_lock, flags);
811 static void __scsi_report_device_reset(struct scsi_device *sdev, void *data)
814 sdev->expecting_cc_ua = 1;
818 * scsi_try_target_reset - Ask host to perform a target reset
819 * @scmd: SCSI cmd used to send a target reset
822 * There is no timeout for this operation. if this operation is
823 * unreliable for a given host, then the host itself needs to put a
824 * timer on it, and set the host back to a consistent state prior to
827 static int scsi_try_target_reset(struct scsi_cmnd *scmd)
831 struct Scsi_Host *host = scmd->device->host;
832 struct scsi_host_template *hostt = host->hostt;
834 if (!hostt->eh_target_reset_handler)
837 rtn = hostt->eh_target_reset_handler(scmd);
838 if (rtn == SUCCESS) {
839 spin_lock_irqsave(host->host_lock, flags);
840 __starget_for_each_device(scsi_target(scmd->device), NULL,
841 __scsi_report_device_reset);
842 spin_unlock_irqrestore(host->host_lock, flags);
849 * scsi_try_bus_device_reset - Ask host to perform a BDR on a dev
850 * @scmd: SCSI cmd used to send BDR
853 * There is no timeout for this operation. if this operation is
854 * unreliable for a given host, then the host itself needs to put a
855 * timer on it, and set the host back to a consistent state prior to
858 static int scsi_try_bus_device_reset(struct scsi_cmnd *scmd)
861 struct scsi_host_template *hostt = scmd->device->host->hostt;
863 if (!hostt->eh_device_reset_handler)
866 rtn = hostt->eh_device_reset_handler(scmd);
868 __scsi_report_device_reset(scmd->device, NULL);
872 static int scsi_try_to_abort_cmd(struct scsi_host_template *hostt, struct scsi_cmnd *scmd)
874 if (!hostt->eh_abort_handler)
877 return hostt->eh_abort_handler(scmd);
880 static void scsi_abort_eh_cmnd(struct scsi_cmnd *scmd)
882 if (scsi_try_to_abort_cmd(scmd->device->host->hostt, scmd) != SUCCESS)
883 if (scsi_try_bus_device_reset(scmd) != SUCCESS)
884 if (scsi_try_target_reset(scmd) != SUCCESS)
885 if (scsi_try_bus_reset(scmd) != SUCCESS)
886 scsi_try_host_reset(scmd);
890 * scsi_eh_prep_cmnd - Save a scsi command info as part of error recovery
891 * @scmd: SCSI command structure to hijack
892 * @ses: structure to save restore information
893 * @cmnd: CDB to send. Can be NULL if no new cmnd is needed
894 * @cmnd_size: size in bytes of @cmnd (must be <= BLK_MAX_CDB)
895 * @sense_bytes: size of sense data to copy. or 0 (if != 0 @cmnd is ignored)
897 * This function is used to save a scsi command information before re-execution
898 * as part of the error recovery process. If @sense_bytes is 0 the command
899 * sent must be one that does not transfer any data. If @sense_bytes != 0
900 * @cmnd is ignored and this functions sets up a REQUEST_SENSE command
901 * and cmnd buffers to read @sense_bytes into @scmd->sense_buffer.
903 void scsi_eh_prep_cmnd(struct scsi_cmnd *scmd, struct scsi_eh_save *ses,
904 unsigned char *cmnd, int cmnd_size, unsigned sense_bytes)
906 struct scsi_device *sdev = scmd->device;
909 * We need saved copies of a number of fields - this is because
910 * error handling may need to overwrite these with different values
911 * to run different commands, and once error handling is complete,
912 * we will need to restore these values prior to running the actual
915 ses->cmd_len = scmd->cmd_len;
916 ses->cmnd = scmd->cmnd;
917 ses->data_direction = scmd->sc_data_direction;
918 ses->sdb = scmd->sdb;
919 ses->next_rq = scmd->request->next_rq;
920 ses->result = scmd->result;
921 ses->underflow = scmd->underflow;
922 ses->prot_op = scmd->prot_op;
924 scmd->prot_op = SCSI_PROT_NORMAL;
926 scmd->cmnd = ses->eh_cmnd;
927 memset(scmd->cmnd, 0, BLK_MAX_CDB);
928 memset(&scmd->sdb, 0, sizeof(scmd->sdb));
929 scmd->request->next_rq = NULL;
933 scmd->sdb.length = min_t(unsigned, SCSI_SENSE_BUFFERSIZE,
935 sg_init_one(&ses->sense_sgl, scmd->sense_buffer,
937 scmd->sdb.table.sgl = &ses->sense_sgl;
938 scmd->sc_data_direction = DMA_FROM_DEVICE;
939 scmd->sdb.table.nents = 1;
940 scmd->cmnd[0] = REQUEST_SENSE;
941 scmd->cmnd[4] = scmd->sdb.length;
942 scmd->cmd_len = COMMAND_SIZE(scmd->cmnd[0]);
944 scmd->sc_data_direction = DMA_NONE;
946 BUG_ON(cmnd_size > BLK_MAX_CDB);
947 memcpy(scmd->cmnd, cmnd, cmnd_size);
948 scmd->cmd_len = COMMAND_SIZE(scmd->cmnd[0]);
954 if (sdev->scsi_level <= SCSI_2 && sdev->scsi_level != SCSI_UNKNOWN)
955 scmd->cmnd[1] = (scmd->cmnd[1] & 0x1f) |
956 (sdev->lun << 5 & 0xe0);
959 * Zero the sense buffer. The scsi spec mandates that any
960 * untransferred sense data should be interpreted as being zero.
962 memset(scmd->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE);
964 EXPORT_SYMBOL(scsi_eh_prep_cmnd);
967 * scsi_eh_restore_cmnd - Restore a scsi command info as part of error recovery
968 * @scmd: SCSI command structure to restore
969 * @ses: saved information from a coresponding call to scsi_eh_prep_cmnd
971 * Undo any damage done by above scsi_eh_prep_cmnd().
973 void scsi_eh_restore_cmnd(struct scsi_cmnd* scmd, struct scsi_eh_save *ses)
976 * Restore original data
978 scmd->cmd_len = ses->cmd_len;
979 scmd->cmnd = ses->cmnd;
980 scmd->sc_data_direction = ses->data_direction;
981 scmd->sdb = ses->sdb;
982 scmd->request->next_rq = ses->next_rq;
983 scmd->result = ses->result;
984 scmd->underflow = ses->underflow;
985 scmd->prot_op = ses->prot_op;
987 EXPORT_SYMBOL(scsi_eh_restore_cmnd);
990 * scsi_send_eh_cmnd - submit a scsi command as part of error recovery
991 * @scmd: SCSI command structure to hijack
993 * @cmnd_size: size in bytes of @cmnd
994 * @timeout: timeout for this request
995 * @sense_bytes: size of sense data to copy or 0
997 * This function is used to send a scsi command down to a target device
998 * as part of the error recovery process. See also scsi_eh_prep_cmnd() above.
1001 * SUCCESS or FAILED or NEEDS_RETRY
1003 static int scsi_send_eh_cmnd(struct scsi_cmnd *scmd, unsigned char *cmnd,
1004 int cmnd_size, int timeout, unsigned sense_bytes)
1006 struct scsi_device *sdev = scmd->device;
1007 struct Scsi_Host *shost = sdev->host;
1008 DECLARE_COMPLETION_ONSTACK(done);
1009 unsigned long timeleft = timeout;
1010 struct scsi_eh_save ses;
1011 const unsigned long stall_for = msecs_to_jiffies(100);
1015 scsi_eh_prep_cmnd(scmd, &ses, cmnd, cmnd_size, sense_bytes);
1016 shost->eh_action = &done;
1018 scsi_log_send(scmd);
1019 scmd->scsi_done = scsi_eh_done;
1020 rtn = shost->hostt->queuecommand(shost, scmd);
1022 if (timeleft > stall_for) {
1023 scsi_eh_restore_cmnd(scmd, &ses);
1024 timeleft -= stall_for;
1025 msleep(jiffies_to_msecs(stall_for));
1028 /* signal not to enter either branch of the if () below */
1032 timeleft = wait_for_completion_timeout(&done, timeout);
1036 shost->eh_action = NULL;
1038 scsi_log_completion(scmd, rtn);
1040 SCSI_LOG_ERROR_RECOVERY(3, scmd_printk(KERN_INFO, scmd,
1041 "%s: scmd: %p, timeleft: %ld\n",
1042 __func__, scmd, timeleft));
1045 * If there is time left scsi_eh_done got called, and we will examine
1046 * the actual status codes to see whether the command actually did
1047 * complete normally, else if we have a zero return and no time left,
1048 * the command must still be pending, so abort it and return FAILED.
1049 * If we never actually managed to issue the command, because
1050 * ->queuecommand() kept returning non zero, use the rtn = FAILED
1051 * value above (so don't execute either branch of the if)
1054 rtn = scsi_eh_completed_normally(scmd);
1055 SCSI_LOG_ERROR_RECOVERY(3, scmd_printk(KERN_INFO, scmd,
1056 "%s: scsi_eh_completed_normally %x\n", __func__, rtn));
1063 case ADD_TO_MLQUEUE:
1071 scsi_abort_eh_cmnd(scmd);
1075 scsi_eh_restore_cmnd(scmd, &ses);
1081 * scsi_request_sense - Request sense data from a particular target.
1082 * @scmd: SCSI cmd for request sense.
1085 * Some hosts automatically obtain this information, others require
1086 * that we obtain it on our own. This function will *not* return until
1087 * the command either times out, or it completes.
1089 static int scsi_request_sense(struct scsi_cmnd *scmd)
1091 return scsi_send_eh_cmnd(scmd, NULL, 0, scmd->device->eh_timeout, ~0);
1094 static int scsi_eh_action(struct scsi_cmnd *scmd, int rtn)
1096 if (scmd->request->cmd_type != REQ_TYPE_BLOCK_PC) {
1097 struct scsi_driver *sdrv = scsi_cmd_to_driver(scmd);
1098 if (sdrv->eh_action)
1099 rtn = sdrv->eh_action(scmd, rtn);
1105 * scsi_eh_finish_cmd - Handle a cmd that eh is finished with.
1106 * @scmd: Original SCSI cmd that eh has finished.
1107 * @done_q: Queue for processed commands.
1110 * We don't want to use the normal command completion while we are are
1111 * still handling errors - it may cause other commands to be queued,
1112 * and that would disturb what we are doing. Thus we really want to
1113 * keep a list of pending commands for final completion, and once we
1114 * are ready to leave error handling we handle completion for real.
1116 void scsi_eh_finish_cmd(struct scsi_cmnd *scmd, struct list_head *done_q)
1118 scmd->device->host->host_failed--;
1119 scmd->eh_eflags = 0;
1120 list_move_tail(&scmd->eh_entry, done_q);
1122 EXPORT_SYMBOL(scsi_eh_finish_cmd);
1125 * scsi_eh_get_sense - Get device sense data.
1126 * @work_q: Queue of commands to process.
1127 * @done_q: Queue of processed commands.
1130 * See if we need to request sense information. if so, then get it
1131 * now, so we have a better idea of what to do.
1134 * This has the unfortunate side effect that if a shost adapter does
1135 * not automatically request sense information, we end up shutting
1136 * it down before we request it.
1138 * All drivers should request sense information internally these days,
1139 * so for now all I have to say is tough noogies if you end up in here.
1141 * XXX: Long term this code should go away, but that needs an audit of
1144 int scsi_eh_get_sense(struct list_head *work_q,
1145 struct list_head *done_q)
1147 struct scsi_cmnd *scmd, *next;
1148 struct Scsi_Host *shost;
1151 list_for_each_entry_safe(scmd, next, work_q, eh_entry) {
1152 if ((scmd->eh_eflags & SCSI_EH_CANCEL_CMD) ||
1153 SCSI_SENSE_VALID(scmd))
1156 shost = scmd->device->host;
1157 if (scsi_host_eh_past_deadline(shost)) {
1158 SCSI_LOG_ERROR_RECOVERY(3,
1159 scmd_printk(KERN_INFO, scmd,
1160 "%s: skip request sense, past eh deadline\n",
1164 if (status_byte(scmd->result) != CHECK_CONDITION)
1166 * don't request sense if there's no check condition
1167 * status because the error we're processing isn't one
1168 * that has a sense code (and some devices get
1169 * confused by sense requests out of the blue)
1173 SCSI_LOG_ERROR_RECOVERY(2, scmd_printk(KERN_INFO, scmd,
1174 "%s: requesting sense\n",
1176 rtn = scsi_request_sense(scmd);
1180 SCSI_LOG_ERROR_RECOVERY(3, scmd_printk(KERN_INFO, scmd,
1181 "sense requested for %p result %x\n",
1182 scmd, scmd->result));
1183 SCSI_LOG_ERROR_RECOVERY(3, scsi_print_sense(scmd));
1185 rtn = scsi_decide_disposition(scmd);
1188 * if the result was normal, then just pass it along to the
1192 /* we don't want this command reissued, just
1193 * finished with the sense data, so set
1194 * retries to the max allowed to ensure it
1195 * won't get reissued */
1196 scmd->retries = scmd->allowed;
1197 else if (rtn != NEEDS_RETRY)
1200 scsi_eh_finish_cmd(scmd, done_q);
1203 return list_empty(work_q);
1205 EXPORT_SYMBOL_GPL(scsi_eh_get_sense);
1208 * scsi_eh_tur - Send TUR to device.
1209 * @scmd: &scsi_cmnd to send TUR
1212 * 0 - Device is ready. 1 - Device NOT ready.
1214 static int scsi_eh_tur(struct scsi_cmnd *scmd)
1216 static unsigned char tur_command[6] = {TEST_UNIT_READY, 0, 0, 0, 0, 0};
1217 int retry_cnt = 1, rtn;
1220 rtn = scsi_send_eh_cmnd(scmd, tur_command, 6,
1221 scmd->device->eh_timeout, 0);
1223 SCSI_LOG_ERROR_RECOVERY(3, scmd_printk(KERN_INFO, scmd,
1224 "%s: scmd %p rtn %x\n", __func__, scmd, rtn));
1239 * scsi_eh_test_devices - check if devices are responding from error recovery.
1240 * @cmd_list: scsi commands in error recovery.
1241 * @work_q: queue for commands which still need more error recovery
1242 * @done_q: queue for commands which are finished
1243 * @try_stu: boolean on if a STU command should be tried in addition to TUR.
1246 * Tests if devices are in a working state. Commands to devices now in
1247 * a working state are sent to the done_q while commands to devices which
1248 * are still failing to respond are returned to the work_q for more
1251 static int scsi_eh_test_devices(struct list_head *cmd_list,
1252 struct list_head *work_q,
1253 struct list_head *done_q, int try_stu)
1255 struct scsi_cmnd *scmd, *next;
1256 struct scsi_device *sdev;
1259 while (!list_empty(cmd_list)) {
1260 scmd = list_entry(cmd_list->next, struct scsi_cmnd, eh_entry);
1261 sdev = scmd->device;
1264 if (scsi_host_eh_past_deadline(sdev->host)) {
1265 /* Push items back onto work_q */
1266 list_splice_init(cmd_list, work_q);
1267 SCSI_LOG_ERROR_RECOVERY(3,
1268 sdev_printk(KERN_INFO, sdev,
1269 "%s: skip test device, past eh deadline",
1275 finish_cmds = !scsi_device_online(scmd->device) ||
1276 (try_stu && !scsi_eh_try_stu(scmd) &&
1277 !scsi_eh_tur(scmd)) ||
1280 list_for_each_entry_safe(scmd, next, cmd_list, eh_entry)
1281 if (scmd->device == sdev) {
1284 scsi_eh_action(scmd, SUCCESS) == SUCCESS))
1285 scsi_eh_finish_cmd(scmd, done_q);
1287 list_move_tail(&scmd->eh_entry, work_q);
1290 return list_empty(work_q);
1295 * scsi_eh_abort_cmds - abort pending commands.
1296 * @work_q: &list_head for pending commands.
1297 * @done_q: &list_head for processed commands.
1300 * Try and see whether or not it makes sense to try and abort the
1301 * running command. This only works out to be the case if we have one
1302 * command that has timed out. If the command simply failed, it makes
1303 * no sense to try and abort the command, since as far as the shost
1304 * adapter is concerned, it isn't running.
1306 static int scsi_eh_abort_cmds(struct list_head *work_q,
1307 struct list_head *done_q)
1309 struct scsi_cmnd *scmd, *next;
1310 LIST_HEAD(check_list);
1312 struct Scsi_Host *shost;
1314 list_for_each_entry_safe(scmd, next, work_q, eh_entry) {
1315 if (!(scmd->eh_eflags & SCSI_EH_CANCEL_CMD))
1317 shost = scmd->device->host;
1318 if (scsi_host_eh_past_deadline(shost)) {
1319 list_splice_init(&check_list, work_q);
1320 SCSI_LOG_ERROR_RECOVERY(3,
1321 scmd_printk(KERN_INFO, scmd,
1322 "%s: skip aborting cmd, past eh deadline\n",
1324 return list_empty(work_q);
1326 SCSI_LOG_ERROR_RECOVERY(3,
1327 scmd_printk(KERN_INFO, scmd,
1328 "%s: aborting cmd\n", current->comm));
1329 rtn = scsi_try_to_abort_cmd(shost->hostt, scmd);
1330 if (rtn == FAILED) {
1331 SCSI_LOG_ERROR_RECOVERY(3,
1332 scmd_printk(KERN_INFO, scmd,
1333 "%s: aborting cmd failed\n",
1335 list_splice_init(&check_list, work_q);
1336 return list_empty(work_q);
1338 scmd->eh_eflags &= ~SCSI_EH_CANCEL_CMD;
1339 if (rtn == FAST_IO_FAIL)
1340 scsi_eh_finish_cmd(scmd, done_q);
1342 list_move_tail(&scmd->eh_entry, &check_list);
1345 return scsi_eh_test_devices(&check_list, work_q, done_q, 0);
1349 * scsi_eh_try_stu - Send START_UNIT to device.
1350 * @scmd: &scsi_cmnd to send START_UNIT
1353 * 0 - Device is ready. 1 - Device NOT ready.
1355 static int scsi_eh_try_stu(struct scsi_cmnd *scmd)
1357 static unsigned char stu_command[6] = {START_STOP, 0, 0, 0, 1, 0};
1359 if (scmd->device->allow_restart) {
1360 int i, rtn = NEEDS_RETRY;
1362 for (i = 0; rtn == NEEDS_RETRY && i < 2; i++)
1363 rtn = scsi_send_eh_cmnd(scmd, stu_command, 6, scmd->device->request_queue->rq_timeout, 0);
1373 * scsi_eh_stu - send START_UNIT if needed
1374 * @shost: &scsi host being recovered.
1375 * @work_q: &list_head for pending commands.
1376 * @done_q: &list_head for processed commands.
1379 * If commands are failing due to not ready, initializing command required,
1380 * try revalidating the device, which will end up sending a start unit.
1382 static int scsi_eh_stu(struct Scsi_Host *shost,
1383 struct list_head *work_q,
1384 struct list_head *done_q)
1386 struct scsi_cmnd *scmd, *stu_scmd, *next;
1387 struct scsi_device *sdev;
1389 shost_for_each_device(sdev, shost) {
1390 if (scsi_host_eh_past_deadline(shost)) {
1391 SCSI_LOG_ERROR_RECOVERY(3,
1392 sdev_printk(KERN_INFO, sdev,
1393 "%s: skip START_UNIT, past eh deadline\n",
1398 list_for_each_entry(scmd, work_q, eh_entry)
1399 if (scmd->device == sdev && SCSI_SENSE_VALID(scmd) &&
1400 scsi_check_sense(scmd) == FAILED ) {
1408 SCSI_LOG_ERROR_RECOVERY(3,
1409 sdev_printk(KERN_INFO, sdev,
1410 "%s: Sending START_UNIT\n",
1413 if (!scsi_eh_try_stu(stu_scmd)) {
1414 if (!scsi_device_online(sdev) ||
1415 !scsi_eh_tur(stu_scmd)) {
1416 list_for_each_entry_safe(scmd, next,
1418 if (scmd->device == sdev &&
1419 scsi_eh_action(scmd, SUCCESS) == SUCCESS)
1420 scsi_eh_finish_cmd(scmd, done_q);
1424 SCSI_LOG_ERROR_RECOVERY(3,
1425 sdev_printk(KERN_INFO, sdev,
1426 "%s: START_UNIT failed\n",
1431 return list_empty(work_q);
1436 * scsi_eh_bus_device_reset - send bdr if needed
1437 * @shost: scsi host being recovered.
1438 * @work_q: &list_head for pending commands.
1439 * @done_q: &list_head for processed commands.
1442 * Try a bus device reset. Still, look to see whether we have multiple
1443 * devices that are jammed or not - if we have multiple devices, it
1444 * makes no sense to try bus_device_reset - we really would need to try
1445 * a bus_reset instead.
1447 static int scsi_eh_bus_device_reset(struct Scsi_Host *shost,
1448 struct list_head *work_q,
1449 struct list_head *done_q)
1451 struct scsi_cmnd *scmd, *bdr_scmd, *next;
1452 struct scsi_device *sdev;
1455 shost_for_each_device(sdev, shost) {
1456 if (scsi_host_eh_past_deadline(shost)) {
1457 SCSI_LOG_ERROR_RECOVERY(3,
1458 sdev_printk(KERN_INFO, sdev,
1459 "%s: skip BDR, past eh deadline\n",
1464 list_for_each_entry(scmd, work_q, eh_entry)
1465 if (scmd->device == sdev) {
1473 SCSI_LOG_ERROR_RECOVERY(3,
1474 sdev_printk(KERN_INFO, sdev,
1475 "%s: Sending BDR\n", current->comm));
1476 rtn = scsi_try_bus_device_reset(bdr_scmd);
1477 if (rtn == SUCCESS || rtn == FAST_IO_FAIL) {
1478 if (!scsi_device_online(sdev) ||
1479 rtn == FAST_IO_FAIL ||
1480 !scsi_eh_tur(bdr_scmd)) {
1481 list_for_each_entry_safe(scmd, next,
1483 if (scmd->device == sdev &&
1484 scsi_eh_action(scmd, rtn) != FAILED)
1485 scsi_eh_finish_cmd(scmd,
1490 SCSI_LOG_ERROR_RECOVERY(3,
1491 sdev_printk(KERN_INFO, sdev,
1492 "%s: BDR failed\n", current->comm));
1496 return list_empty(work_q);
1500 * scsi_eh_target_reset - send target reset if needed
1501 * @shost: scsi host being recovered.
1502 * @work_q: &list_head for pending commands.
1503 * @done_q: &list_head for processed commands.
1506 * Try a target reset.
1508 static int scsi_eh_target_reset(struct Scsi_Host *shost,
1509 struct list_head *work_q,
1510 struct list_head *done_q)
1512 LIST_HEAD(tmp_list);
1513 LIST_HEAD(check_list);
1515 list_splice_init(work_q, &tmp_list);
1517 while (!list_empty(&tmp_list)) {
1518 struct scsi_cmnd *next, *scmd;
1522 if (scsi_host_eh_past_deadline(shost)) {
1523 /* push back on work queue for further processing */
1524 list_splice_init(&check_list, work_q);
1525 list_splice_init(&tmp_list, work_q);
1526 SCSI_LOG_ERROR_RECOVERY(3,
1527 shost_printk(KERN_INFO, shost,
1528 "%s: Skip target reset, past eh deadline\n",
1530 return list_empty(work_q);
1533 scmd = list_entry(tmp_list.next, struct scsi_cmnd, eh_entry);
1536 SCSI_LOG_ERROR_RECOVERY(3,
1537 shost_printk(KERN_INFO, shost,
1538 "%s: Sending target reset to target %d\n",
1539 current->comm, id));
1540 rtn = scsi_try_target_reset(scmd);
1541 if (rtn != SUCCESS && rtn != FAST_IO_FAIL)
1542 SCSI_LOG_ERROR_RECOVERY(3,
1543 shost_printk(KERN_INFO, shost,
1544 "%s: Target reset failed"
1546 current->comm, id));
1547 list_for_each_entry_safe(scmd, next, &tmp_list, eh_entry) {
1548 if (scmd_id(scmd) != id)
1552 list_move_tail(&scmd->eh_entry, &check_list);
1553 else if (rtn == FAST_IO_FAIL)
1554 scsi_eh_finish_cmd(scmd, done_q);
1556 /* push back on work queue for further processing */
1557 list_move(&scmd->eh_entry, work_q);
1561 return scsi_eh_test_devices(&check_list, work_q, done_q, 0);
1565 * scsi_eh_bus_reset - send a bus reset
1566 * @shost: &scsi host being recovered.
1567 * @work_q: &list_head for pending commands.
1568 * @done_q: &list_head for processed commands.
1570 static int scsi_eh_bus_reset(struct Scsi_Host *shost,
1571 struct list_head *work_q,
1572 struct list_head *done_q)
1574 struct scsi_cmnd *scmd, *chan_scmd, *next;
1575 LIST_HEAD(check_list);
1576 unsigned int channel;
1580 * we really want to loop over the various channels, and do this on
1581 * a channel by channel basis. we should also check to see if any
1582 * of the failed commands are on soft_reset devices, and if so, skip
1586 for (channel = 0; channel <= shost->max_channel; channel++) {
1587 if (scsi_host_eh_past_deadline(shost)) {
1588 list_splice_init(&check_list, work_q);
1589 SCSI_LOG_ERROR_RECOVERY(3,
1590 shost_printk(KERN_INFO, shost,
1591 "%s: skip BRST, past eh deadline\n",
1593 return list_empty(work_q);
1597 list_for_each_entry(scmd, work_q, eh_entry) {
1598 if (channel == scmd_channel(scmd)) {
1602 * FIXME add back in some support for
1603 * soft_reset devices.
1610 SCSI_LOG_ERROR_RECOVERY(3,
1611 shost_printk(KERN_INFO, shost,
1612 "%s: Sending BRST chan: %d\n",
1613 current->comm, channel));
1614 rtn = scsi_try_bus_reset(chan_scmd);
1615 if (rtn == SUCCESS || rtn == FAST_IO_FAIL) {
1616 list_for_each_entry_safe(scmd, next, work_q, eh_entry) {
1617 if (channel == scmd_channel(scmd)) {
1618 if (rtn == FAST_IO_FAIL)
1619 scsi_eh_finish_cmd(scmd,
1622 list_move_tail(&scmd->eh_entry,
1627 SCSI_LOG_ERROR_RECOVERY(3,
1628 shost_printk(KERN_INFO, shost,
1629 "%s: BRST failed chan: %d\n",
1630 current->comm, channel));
1633 return scsi_eh_test_devices(&check_list, work_q, done_q, 0);
1637 * scsi_eh_host_reset - send a host reset
1638 * @shost: host to be reset.
1639 * @work_q: &list_head for pending commands.
1640 * @done_q: &list_head for processed commands.
1642 static int scsi_eh_host_reset(struct Scsi_Host *shost,
1643 struct list_head *work_q,
1644 struct list_head *done_q)
1646 struct scsi_cmnd *scmd, *next;
1647 LIST_HEAD(check_list);
1650 if (!list_empty(work_q)) {
1651 scmd = list_entry(work_q->next,
1652 struct scsi_cmnd, eh_entry);
1654 SCSI_LOG_ERROR_RECOVERY(3,
1655 shost_printk(KERN_INFO, shost,
1656 "%s: Sending HRST\n",
1659 rtn = scsi_try_host_reset(scmd);
1660 if (rtn == SUCCESS) {
1661 list_splice_init(work_q, &check_list);
1662 } else if (rtn == FAST_IO_FAIL) {
1663 list_for_each_entry_safe(scmd, next, work_q, eh_entry) {
1664 scsi_eh_finish_cmd(scmd, done_q);
1667 SCSI_LOG_ERROR_RECOVERY(3,
1668 shost_printk(KERN_INFO, shost,
1669 "%s: HRST failed\n",
1673 return scsi_eh_test_devices(&check_list, work_q, done_q, 1);
1677 * scsi_eh_offline_sdevs - offline scsi devices that fail to recover
1678 * @work_q: &list_head for pending commands.
1679 * @done_q: &list_head for processed commands.
1681 static void scsi_eh_offline_sdevs(struct list_head *work_q,
1682 struct list_head *done_q)
1684 struct scsi_cmnd *scmd, *next;
1686 list_for_each_entry_safe(scmd, next, work_q, eh_entry) {
1687 sdev_printk(KERN_INFO, scmd->device, "Device offlined - "
1688 "not ready after error recovery\n");
1689 scsi_device_set_state(scmd->device, SDEV_OFFLINE);
1690 if (scmd->eh_eflags & SCSI_EH_CANCEL_CMD) {
1692 * FIXME: Handle lost cmds.
1695 scsi_eh_finish_cmd(scmd, done_q);
1701 * scsi_noretry_cmd - determine if command should be failed fast
1702 * @scmd: SCSI cmd to examine.
1704 int scsi_noretry_cmd(struct scsi_cmnd *scmd)
1706 switch (host_byte(scmd->result)) {
1712 return (scmd->request->cmd_flags & REQ_FAILFAST_TRANSPORT);
1714 return (scmd->request->cmd_flags & REQ_FAILFAST_DEV);
1716 if (msg_byte(scmd->result) == COMMAND_COMPLETE &&
1717 status_byte(scmd->result) == RESERVATION_CONFLICT)
1720 case DID_SOFT_ERROR:
1721 return (scmd->request->cmd_flags & REQ_FAILFAST_DRIVER);
1724 if (status_byte(scmd->result) != CHECK_CONDITION)
1729 * assume caller has checked sense and determined
1730 * the check condition was retryable.
1732 if (scmd->request->cmd_flags & REQ_FAILFAST_DEV ||
1733 scmd->request->cmd_type == REQ_TYPE_BLOCK_PC)
1740 * scsi_decide_disposition - Disposition a cmd on return from LLD.
1741 * @scmd: SCSI cmd to examine.
1744 * This is *only* called when we are examining the status after sending
1745 * out the actual data command. any commands that are queued for error
1746 * recovery (e.g. test_unit_ready) do *not* come through here.
1748 * When this routine returns failed, it means the error handler thread
1749 * is woken. In cases where the error code indicates an error that
1750 * doesn't require the error handler read (i.e. we don't need to
1751 * abort/reset), this function should return SUCCESS.
1753 int scsi_decide_disposition(struct scsi_cmnd *scmd)
1758 * if the device is offline, then we clearly just pass the result back
1759 * up to the top level.
1761 if (!scsi_device_online(scmd->device)) {
1762 SCSI_LOG_ERROR_RECOVERY(5, scmd_printk(KERN_INFO, scmd,
1763 "%s: device offline - report as SUCCESS\n", __func__));
1768 * first check the host byte, to see if there is anything in there
1769 * that would indicate what we need to do.
1771 switch (host_byte(scmd->result)) {
1772 case DID_PASSTHROUGH:
1774 * no matter what, pass this through to the upper layer.
1775 * nuke this special code so that it looks like we are saying
1778 scmd->result &= 0xff00ffff;
1782 * looks good. drop through, and check the next byte.
1786 if (scmd->eh_eflags & SCSI_EH_ABORT_SCHEDULED) {
1787 set_host_byte(scmd, DID_TIME_OUT);
1790 case DID_NO_CONNECT:
1791 case DID_BAD_TARGET:
1793 * note - this means that we just report the status back
1794 * to the top level driver, not that we actually think
1795 * that it indicates SUCCESS.
1799 * when the low level driver returns did_soft_error,
1800 * it is responsible for keeping an internal retry counter
1801 * in order to avoid endless loops (db)
1803 * actually this is a bug in this function here. we should
1804 * be mindful of the maximum number of retries specified
1805 * and not get stuck in a loop.
1807 case DID_SOFT_ERROR:
1813 return ADD_TO_MLQUEUE;
1814 case DID_TRANSPORT_DISRUPTED:
1816 * LLD/transport was disrupted during processing of the IO.
1817 * The transport class is now blocked/blocking,
1818 * and the transport will decide what to do with the IO
1819 * based on its timers and recovery capablilities if
1820 * there are enough retries.
1823 case DID_TRANSPORT_FAILFAST:
1825 * The transport decided to failfast the IO (most likely
1826 * the fast io fail tmo fired), so send IO directly upwards.
1830 if (msg_byte(scmd->result) == COMMAND_COMPLETE &&
1831 status_byte(scmd->result) == RESERVATION_CONFLICT)
1833 * execute reservation conflict processing code
1843 * when we scan the bus, we get timeout messages for
1844 * these commands if there is no device available.
1845 * other hosts report did_no_connect for the same thing.
1847 if ((scmd->cmnd[0] == TEST_UNIT_READY ||
1848 scmd->cmnd[0] == INQUIRY)) {
1860 * next, check the message byte.
1862 if (msg_byte(scmd->result) != COMMAND_COMPLETE)
1866 * check the status byte to see if this indicates anything special.
1868 switch (status_byte(scmd->result)) {
1870 scsi_handle_queue_full(scmd->device);
1872 * the case of trying to send too many commands to a
1873 * tagged queueing device.
1877 * device can't talk to us at the moment. Should only
1878 * occur (SAM-3) when the task queue is empty, so will cause
1879 * the empty queue handling to trigger a stall in the
1882 return ADD_TO_MLQUEUE;
1884 if (scmd->cmnd[0] == REPORT_LUNS)
1885 scmd->device->sdev_target->expecting_lun_change = 0;
1886 scsi_handle_queue_ramp_up(scmd->device);
1887 case COMMAND_TERMINATED:
1891 case CHECK_CONDITION:
1892 rtn = scsi_check_sense(scmd);
1893 if (rtn == NEEDS_RETRY)
1895 /* if rtn == FAILED, we have no sense information;
1896 * returning FAILED will wake the error handler thread
1897 * to collect the sense and redo the decide
1900 case CONDITION_GOOD:
1901 case INTERMEDIATE_GOOD:
1902 case INTERMEDIATE_C_GOOD:
1905 * who knows? FIXME(eric)
1909 case RESERVATION_CONFLICT:
1910 sdev_printk(KERN_INFO, scmd->device,
1911 "reservation conflict\n");
1912 set_host_byte(scmd, DID_NEXUS_FAILURE);
1913 return SUCCESS; /* causes immediate i/o error */
1921 /* we requeue for retry because the error was retryable, and
1922 * the request was not marked fast fail. Note that above,
1923 * even if the request is marked fast fail, we still requeue
1924 * for queue congestion conditions (QUEUE_FULL or BUSY) */
1925 if ((++scmd->retries) <= scmd->allowed
1926 && !scsi_noretry_cmd(scmd)) {
1930 * no more retries - report this one back to upper level.
1936 static void eh_lock_door_done(struct request *req, int uptodate)
1938 __blk_put_request(req->q, req);
1942 * scsi_eh_lock_door - Prevent medium removal for the specified device
1943 * @sdev: SCSI device to prevent medium removal
1946 * We must be called from process context.
1949 * We queue up an asynchronous "ALLOW MEDIUM REMOVAL" request on the
1950 * head of the devices request queue, and continue.
1952 static void scsi_eh_lock_door(struct scsi_device *sdev)
1954 struct request *req;
1957 * blk_get_request with GFP_KERNEL (__GFP_WAIT) sleeps until a
1958 * request becomes available
1960 req = blk_get_request(sdev->request_queue, READ, GFP_KERNEL);
1964 blk_rq_set_block_pc(req);
1966 req->cmd[0] = ALLOW_MEDIUM_REMOVAL;
1970 req->cmd[4] = SCSI_REMOVAL_PREVENT;
1973 req->cmd_len = COMMAND_SIZE(req->cmd[0]);
1975 req->cmd_flags |= REQ_QUIET;
1976 req->timeout = 10 * HZ;
1979 blk_execute_rq_nowait(req->q, NULL, req, 1, eh_lock_door_done);
1983 * scsi_restart_operations - restart io operations to the specified host.
1984 * @shost: Host we are restarting.
1987 * When we entered the error handler, we blocked all further i/o to
1988 * this device. we need to 'reverse' this process.
1990 static void scsi_restart_operations(struct Scsi_Host *shost)
1992 struct scsi_device *sdev;
1993 unsigned long flags;
1996 * If the door was locked, we need to insert a door lock request
1997 * onto the head of the SCSI request queue for the device. There
1998 * is no point trying to lock the door of an off-line device.
2000 shost_for_each_device(sdev, shost) {
2001 if (scsi_device_online(sdev) && sdev->was_reset && sdev->locked) {
2002 scsi_eh_lock_door(sdev);
2003 sdev->was_reset = 0;
2008 * next free up anything directly waiting upon the host. this
2009 * will be requests for character device operations, and also for
2010 * ioctls to queued block devices.
2012 SCSI_LOG_ERROR_RECOVERY(3,
2013 shost_printk(KERN_INFO, shost, "waking up host to restart\n"));
2015 spin_lock_irqsave(shost->host_lock, flags);
2016 if (scsi_host_set_state(shost, SHOST_RUNNING))
2017 if (scsi_host_set_state(shost, SHOST_CANCEL))
2018 BUG_ON(scsi_host_set_state(shost, SHOST_DEL));
2019 spin_unlock_irqrestore(shost->host_lock, flags);
2021 wake_up(&shost->host_wait);
2024 * finally we need to re-initiate requests that may be pending. we will
2025 * have had everything blocked while error handling is taking place, and
2026 * now that error recovery is done, we will need to ensure that these
2027 * requests are started.
2029 scsi_run_host_queues(shost);
2032 * if eh is active and host_eh_scheduled is pending we need to re-run
2033 * recovery. we do this check after scsi_run_host_queues() to allow
2034 * everything pent up since the last eh run a chance to make forward
2035 * progress before we sync again. Either we'll immediately re-run
2036 * recovery or scsi_device_unbusy() will wake us again when these
2037 * pending commands complete.
2039 spin_lock_irqsave(shost->host_lock, flags);
2040 if (shost->host_eh_scheduled)
2041 if (scsi_host_set_state(shost, SHOST_RECOVERY))
2042 WARN_ON(scsi_host_set_state(shost, SHOST_CANCEL_RECOVERY));
2043 spin_unlock_irqrestore(shost->host_lock, flags);
2047 * scsi_eh_ready_devs - check device ready state and recover if not.
2048 * @shost: host to be recovered.
2049 * @work_q: &list_head for pending commands.
2050 * @done_q: &list_head for processed commands.
2052 void scsi_eh_ready_devs(struct Scsi_Host *shost,
2053 struct list_head *work_q,
2054 struct list_head *done_q)
2056 if (!scsi_eh_stu(shost, work_q, done_q))
2057 if (!scsi_eh_bus_device_reset(shost, work_q, done_q))
2058 if (!scsi_eh_target_reset(shost, work_q, done_q))
2059 if (!scsi_eh_bus_reset(shost, work_q, done_q))
2060 if (!scsi_eh_host_reset(shost, work_q, done_q))
2061 scsi_eh_offline_sdevs(work_q,
2064 EXPORT_SYMBOL_GPL(scsi_eh_ready_devs);
2067 * scsi_eh_flush_done_q - finish processed commands or retry them.
2068 * @done_q: list_head of processed commands.
2070 void scsi_eh_flush_done_q(struct list_head *done_q)
2072 struct scsi_cmnd *scmd, *next;
2074 list_for_each_entry_safe(scmd, next, done_q, eh_entry) {
2075 list_del_init(&scmd->eh_entry);
2076 if (scsi_device_online(scmd->device) &&
2077 !scsi_noretry_cmd(scmd) &&
2078 (++scmd->retries <= scmd->allowed)) {
2079 SCSI_LOG_ERROR_RECOVERY(3,
2080 scmd_printk(KERN_INFO, scmd,
2081 "%s: flush retry cmd: %p\n",
2082 current->comm, scmd));
2083 scsi_queue_insert(scmd, SCSI_MLQUEUE_EH_RETRY);
2086 * If just we got sense for the device (called
2087 * scsi_eh_get_sense), scmd->result is already
2088 * set, do not set DRIVER_TIMEOUT.
2091 scmd->result |= (DRIVER_TIMEOUT << 24);
2092 SCSI_LOG_ERROR_RECOVERY(3,
2093 scmd_printk(KERN_INFO, scmd,
2094 "%s: flush finish cmd: %p\n",
2095 current->comm, scmd));
2096 scsi_finish_command(scmd);
2100 EXPORT_SYMBOL(scsi_eh_flush_done_q);
2103 * scsi_unjam_host - Attempt to fix a host which has a cmd that failed.
2104 * @shost: Host to unjam.
2107 * When we come in here, we *know* that all commands on the bus have
2108 * either completed, failed or timed out. we also know that no further
2109 * commands are being sent to the host, so things are relatively quiet
2110 * and we have freedom to fiddle with things as we wish.
2112 * This is only the *default* implementation. it is possible for
2113 * individual drivers to supply their own version of this function, and
2114 * if the maintainer wishes to do this, it is strongly suggested that
2115 * this function be taken as a template and modified. this function
2116 * was designed to correctly handle problems for about 95% of the
2117 * different cases out there, and it should always provide at least a
2118 * reasonable amount of error recovery.
2120 * Any command marked 'failed' or 'timeout' must eventually have
2121 * scsi_finish_cmd() called for it. we do all of the retry stuff
2122 * here, so when we restart the host after we return it should have an
2125 static void scsi_unjam_host(struct Scsi_Host *shost)
2127 unsigned long flags;
2128 LIST_HEAD(eh_work_q);
2129 LIST_HEAD(eh_done_q);
2131 spin_lock_irqsave(shost->host_lock, flags);
2132 list_splice_init(&shost->eh_cmd_q, &eh_work_q);
2133 spin_unlock_irqrestore(shost->host_lock, flags);
2135 SCSI_LOG_ERROR_RECOVERY(1, scsi_eh_prt_fail_stats(shost, &eh_work_q));
2137 if (!scsi_eh_get_sense(&eh_work_q, &eh_done_q))
2138 if (!scsi_eh_abort_cmds(&eh_work_q, &eh_done_q))
2139 scsi_eh_ready_devs(shost, &eh_work_q, &eh_done_q);
2141 spin_lock_irqsave(shost->host_lock, flags);
2142 if (shost->eh_deadline != -1)
2143 shost->last_reset = 0;
2144 spin_unlock_irqrestore(shost->host_lock, flags);
2145 scsi_eh_flush_done_q(&eh_done_q);
2149 * scsi_error_handler - SCSI error handler thread
2150 * @data: Host for which we are running.
2153 * This is the main error handling loop. This is run as a kernel thread
2154 * for every SCSI host and handles all error handling activity.
2156 int scsi_error_handler(void *data)
2158 struct Scsi_Host *shost = data;
2161 * We use TASK_INTERRUPTIBLE so that the thread is not
2162 * counted against the load average as a running process.
2163 * We never actually get interrupted because kthread_run
2164 * disables signal delivery for the created thread.
2166 while (!kthread_should_stop()) {
2167 set_current_state(TASK_INTERRUPTIBLE);
2168 if ((shost->host_failed == 0 && shost->host_eh_scheduled == 0) ||
2169 shost->host_failed != atomic_read(&shost->host_busy)) {
2170 SCSI_LOG_ERROR_RECOVERY(1,
2171 shost_printk(KERN_INFO, shost,
2172 "scsi_eh_%d: sleeping\n",
2178 __set_current_state(TASK_RUNNING);
2179 SCSI_LOG_ERROR_RECOVERY(1,
2180 shost_printk(KERN_INFO, shost,
2181 "scsi_eh_%d: waking up %d/%d/%d\n",
2182 shost->host_no, shost->host_eh_scheduled,
2184 atomic_read(&shost->host_busy)));
2187 * We have a host that is failing for some reason. Figure out
2188 * what we need to do to get it up and online again (if we can).
2189 * If we fail, we end up taking the thing offline.
2191 if (!shost->eh_noresume && scsi_autopm_get_host(shost) != 0) {
2192 SCSI_LOG_ERROR_RECOVERY(1,
2193 shost_printk(KERN_ERR, shost,
2194 "scsi_eh_%d: unable to autoresume\n",
2199 if (shost->transportt->eh_strategy_handler)
2200 shost->transportt->eh_strategy_handler(shost);
2202 scsi_unjam_host(shost);
2205 * Note - if the above fails completely, the action is to take
2206 * individual devices offline and flush the queue of any
2207 * outstanding requests that may have been pending. When we
2208 * restart, we restart any I/O to any other devices on the bus
2209 * which are still online.
2211 scsi_restart_operations(shost);
2212 if (!shost->eh_noresume)
2213 scsi_autopm_put_host(shost);
2215 __set_current_state(TASK_RUNNING);
2217 SCSI_LOG_ERROR_RECOVERY(1,
2218 shost_printk(KERN_INFO, shost,
2219 "Error handler scsi_eh_%d exiting\n",
2221 shost->ehandler = NULL;
2226 * Function: scsi_report_bus_reset()
2228 * Purpose: Utility function used by low-level drivers to report that
2229 * they have observed a bus reset on the bus being handled.
2231 * Arguments: shost - Host in question
2232 * channel - channel on which reset was observed.
2236 * Lock status: Host lock must be held.
2238 * Notes: This only needs to be called if the reset is one which
2239 * originates from an unknown location. Resets originated
2240 * by the mid-level itself don't need to call this, but there
2241 * should be no harm.
2243 * The main purpose of this is to make sure that a CHECK_CONDITION
2244 * is properly treated.
2246 void scsi_report_bus_reset(struct Scsi_Host *shost, int channel)
2248 struct scsi_device *sdev;
2250 __shost_for_each_device(sdev, shost) {
2251 if (channel == sdev_channel(sdev))
2252 __scsi_report_device_reset(sdev, NULL);
2255 EXPORT_SYMBOL(scsi_report_bus_reset);
2258 * Function: scsi_report_device_reset()
2260 * Purpose: Utility function used by low-level drivers to report that
2261 * they have observed a device reset on the device being handled.
2263 * Arguments: shost - Host in question
2264 * channel - channel on which reset was observed
2265 * target - target on which reset was observed
2269 * Lock status: Host lock must be held
2271 * Notes: This only needs to be called if the reset is one which
2272 * originates from an unknown location. Resets originated
2273 * by the mid-level itself don't need to call this, but there
2274 * should be no harm.
2276 * The main purpose of this is to make sure that a CHECK_CONDITION
2277 * is properly treated.
2279 void scsi_report_device_reset(struct Scsi_Host *shost, int channel, int target)
2281 struct scsi_device *sdev;
2283 __shost_for_each_device(sdev, shost) {
2284 if (channel == sdev_channel(sdev) &&
2285 target == sdev_id(sdev))
2286 __scsi_report_device_reset(sdev, NULL);
2289 EXPORT_SYMBOL(scsi_report_device_reset);
2292 scsi_reset_provider_done_command(struct scsi_cmnd *scmd)
2297 * Function: scsi_reset_provider
2299 * Purpose: Send requested reset to a bus or device at any phase.
2301 * Arguments: device - device to send reset to
2302 * flag - reset type (see scsi.h)
2304 * Returns: SUCCESS/FAILURE.
2306 * Notes: This is used by the SCSI Generic driver to provide
2307 * Bus/Device reset capability.
2310 scsi_reset_provider(struct scsi_device *dev, int flag)
2312 struct scsi_cmnd *scmd;
2313 struct Scsi_Host *shost = dev->host;
2315 unsigned long flags;
2318 if (scsi_autopm_get_host(shost) < 0)
2321 if (!get_device(&dev->sdev_gendev)) {
2323 goto out_put_autopm_host;
2326 scmd = scsi_get_command(dev, GFP_KERNEL);
2329 put_device(&dev->sdev_gendev);
2330 goto out_put_autopm_host;
2333 blk_rq_init(NULL, &req);
2334 scmd->request = &req;
2336 scmd->cmnd = req.cmd;
2338 scmd->scsi_done = scsi_reset_provider_done_command;
2339 memset(&scmd->sdb, 0, sizeof(scmd->sdb));
2343 scmd->sc_data_direction = DMA_BIDIRECTIONAL;
2345 spin_lock_irqsave(shost->host_lock, flags);
2346 shost->tmf_in_progress = 1;
2347 spin_unlock_irqrestore(shost->host_lock, flags);
2350 case SCSI_TRY_RESET_DEVICE:
2351 rtn = scsi_try_bus_device_reset(scmd);
2355 case SCSI_TRY_RESET_TARGET:
2356 rtn = scsi_try_target_reset(scmd);
2360 case SCSI_TRY_RESET_BUS:
2361 rtn = scsi_try_bus_reset(scmd);
2365 case SCSI_TRY_RESET_HOST:
2366 case SCSI_TRY_RESET_HOST | SCSI_TRY_RESET_NO_ESCALATE:
2367 rtn = scsi_try_host_reset(scmd);
2369 case SCSI_TRY_RESET_DEVICE | SCSI_TRY_RESET_NO_ESCALATE:
2370 rtn = scsi_try_bus_device_reset(scmd);
2372 case SCSI_TRY_RESET_TARGET | SCSI_TRY_RESET_NO_ESCALATE:
2373 rtn = scsi_try_target_reset(scmd);
2375 case SCSI_TRY_RESET_BUS | SCSI_TRY_RESET_NO_ESCALATE:
2376 rtn = scsi_try_bus_reset(scmd);
2382 spin_lock_irqsave(shost->host_lock, flags);
2383 shost->tmf_in_progress = 0;
2384 spin_unlock_irqrestore(shost->host_lock, flags);
2387 * be sure to wake up anyone who was sleeping or had their queue
2388 * suspended while we performed the TMF.
2390 SCSI_LOG_ERROR_RECOVERY(3,
2391 shost_printk(KERN_INFO, shost,
2392 "waking up host to restart after TMF\n"));
2394 wake_up(&shost->host_wait);
2396 scsi_run_host_queues(shost);
2398 scsi_next_command(scmd);
2399 out_put_autopm_host:
2400 scsi_autopm_put_host(shost);
2403 EXPORT_SYMBOL(scsi_reset_provider);
2406 * scsi_normalize_sense - normalize main elements from either fixed or
2407 * descriptor sense data format into a common format.
2409 * @sense_buffer: byte array containing sense data returned by device
2410 * @sb_len: number of valid bytes in sense_buffer
2411 * @sshdr: pointer to instance of structure that common
2412 * elements are written to.
2415 * The "main elements" from sense data are: response_code, sense_key,
2416 * asc, ascq and additional_length (only for descriptor format).
2418 * Typically this function can be called after a device has
2419 * responded to a SCSI command with the CHECK_CONDITION status.
2422 * true if valid sense data information found, else false;
2424 bool scsi_normalize_sense(const u8 *sense_buffer, int sb_len,
2425 struct scsi_sense_hdr *sshdr)
2427 if (!sense_buffer || !sb_len)
2430 memset(sshdr, 0, sizeof(struct scsi_sense_hdr));
2432 sshdr->response_code = (sense_buffer[0] & 0x7f);
2434 if (!scsi_sense_valid(sshdr))
2437 if (sshdr->response_code >= 0x72) {
2442 sshdr->sense_key = (sense_buffer[1] & 0xf);
2444 sshdr->asc = sense_buffer[2];
2446 sshdr->ascq = sense_buffer[3];
2448 sshdr->additional_length = sense_buffer[7];
2454 sshdr->sense_key = (sense_buffer[2] & 0xf);
2456 sb_len = (sb_len < (sense_buffer[7] + 8)) ?
2457 sb_len : (sense_buffer[7] + 8);
2459 sshdr->asc = sense_buffer[12];
2461 sshdr->ascq = sense_buffer[13];
2467 EXPORT_SYMBOL(scsi_normalize_sense);
2469 bool scsi_command_normalize_sense(const struct scsi_cmnd *cmd,
2470 struct scsi_sense_hdr *sshdr)
2472 return scsi_normalize_sense(cmd->sense_buffer,
2473 SCSI_SENSE_BUFFERSIZE, sshdr);
2475 EXPORT_SYMBOL(scsi_command_normalize_sense);
2478 * scsi_sense_desc_find - search for a given descriptor type in descriptor sense data format.
2479 * @sense_buffer: byte array of descriptor format sense data
2480 * @sb_len: number of valid bytes in sense_buffer
2481 * @desc_type: value of descriptor type to find
2482 * (e.g. 0 -> information)
2485 * only valid when sense data is in descriptor format
2488 * pointer to start of (first) descriptor if found else NULL
2490 const u8 * scsi_sense_desc_find(const u8 * sense_buffer, int sb_len,
2493 int add_sen_len, add_len, desc_len, k;
2496 if ((sb_len < 8) || (0 == (add_sen_len = sense_buffer[7])))
2498 if ((sense_buffer[0] < 0x72) || (sense_buffer[0] > 0x73))
2500 add_sen_len = (add_sen_len < (sb_len - 8)) ?
2501 add_sen_len : (sb_len - 8);
2502 descp = &sense_buffer[8];
2503 for (desc_len = 0, k = 0; k < add_sen_len; k += desc_len) {
2505 add_len = (k < (add_sen_len - 1)) ? descp[1]: -1;
2506 desc_len = add_len + 2;
2507 if (descp[0] == desc_type)
2509 if (add_len < 0) // short descriptor ??
2514 EXPORT_SYMBOL(scsi_sense_desc_find);
2517 * scsi_get_sense_info_fld - get information field from sense data (either fixed or descriptor format)
2518 * @sense_buffer: byte array of sense data
2519 * @sb_len: number of valid bytes in sense_buffer
2520 * @info_out: pointer to 64 integer where 8 or 4 byte information
2521 * field will be placed if found.
2524 * 1 if information field found, 0 if not found.
2526 int scsi_get_sense_info_fld(const u8 * sense_buffer, int sb_len,
2535 switch (sense_buffer[0] & 0x7f) {
2538 if (sense_buffer[0] & 0x80) {
2539 *info_out = (sense_buffer[3] << 24) +
2540 (sense_buffer[4] << 16) +
2541 (sense_buffer[5] << 8) + sense_buffer[6];
2547 ucp = scsi_sense_desc_find(sense_buffer, sb_len,
2549 if (ucp && (0xa == ucp[1])) {
2551 for (j = 0; j < 8; ++j) {
2564 EXPORT_SYMBOL(scsi_get_sense_info_fld);
2567 * scsi_build_sense_buffer - build sense data in a buffer
2568 * @desc: Sense format (non zero == descriptor format,
2569 * 0 == fixed format)
2570 * @buf: Where to build sense data
2572 * @asc: Additional sense code
2573 * @ascq: Additional sense code qualifier
2576 void scsi_build_sense_buffer(int desc, u8 *buf, u8 key, u8 asc, u8 ascq)
2579 buf[0] = 0x72; /* descriptor, current */
2585 buf[0] = 0x70; /* fixed, current */
2592 EXPORT_SYMBOL(scsi_build_sense_buffer);