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 (shost->host_busy == shost->host_failed) {
63 trace_scsi_eh_wakeup(shost);
64 wake_up_process(shost->ehandler);
65 SCSI_LOG_ERROR_RECOVERY(5,
66 printk("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 scmd->result |= DID_TIME_OUT << 16;
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 scmd->result |= DID_TIME_OUT << 16;
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 cancel_delayed_work(&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 && !host->hostt->no_async_abort)
291 if (scsi_abort_command(scmd) == SUCCESS)
292 return BLK_EH_NOT_HANDLED;
294 scmd->result |= DID_TIME_OUT << 16;
296 if (unlikely(rtn == BLK_EH_NOT_HANDLED &&
297 !scsi_eh_scmd_add(scmd, SCSI_EH_CANCEL_CMD)))
298 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, printk("%s: rtn: %d\n", __func__,
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, printk("Total of %d commands on %d"
369 " devices require eh work\n",
370 total_failures, devices_failed));
375 * scsi_report_lun_change - Set flag on all *other* devices on the same target
376 * to indicate that a UNIT ATTENTION is expected.
377 * @sdev: Device reporting the UNIT ATTENTION
379 static void scsi_report_lun_change(struct scsi_device *sdev)
381 sdev->sdev_target->expecting_lun_change = 1;
385 * scsi_report_sense - Examine scsi sense information and log messages for
386 * certain conditions, also issue uevents for some of them.
387 * @sdev: Device reporting the sense code
388 * @sshdr: sshdr to be examined
390 static void scsi_report_sense(struct scsi_device *sdev,
391 struct scsi_sense_hdr *sshdr)
393 enum scsi_device_event evt_type = SDEV_EVT_MAXBITS; /* i.e. none */
395 if (sshdr->sense_key == UNIT_ATTENTION) {
396 if (sshdr->asc == 0x3f && sshdr->ascq == 0x03) {
397 evt_type = SDEV_EVT_INQUIRY_CHANGE_REPORTED;
398 sdev_printk(KERN_WARNING, sdev,
399 "Inquiry data has changed");
400 } else if (sshdr->asc == 0x3f && sshdr->ascq == 0x0e) {
401 evt_type = SDEV_EVT_LUN_CHANGE_REPORTED;
402 scsi_report_lun_change(sdev);
403 sdev_printk(KERN_WARNING, sdev,
404 "Warning! Received an indication that the "
405 "LUN assignments on this target have "
406 "changed. The Linux SCSI layer does not "
407 "automatically remap LUN assignments.\n");
408 } else if (sshdr->asc == 0x3f)
409 sdev_printk(KERN_WARNING, sdev,
410 "Warning! Received an indication that the "
411 "operating parameters on this target have "
412 "changed. The Linux SCSI layer does not "
413 "automatically adjust these parameters.\n");
415 if (sshdr->asc == 0x38 && sshdr->ascq == 0x07) {
416 evt_type = SDEV_EVT_SOFT_THRESHOLD_REACHED_REPORTED;
417 sdev_printk(KERN_WARNING, sdev,
418 "Warning! Received an indication that the "
419 "LUN reached a thin provisioning soft "
423 if (sshdr->asc == 0x2a && sshdr->ascq == 0x01) {
424 evt_type = SDEV_EVT_MODE_PARAMETER_CHANGE_REPORTED;
425 sdev_printk(KERN_WARNING, sdev,
426 "Mode parameters changed");
427 } else if (sshdr->asc == 0x2a && sshdr->ascq == 0x09) {
428 evt_type = SDEV_EVT_CAPACITY_CHANGE_REPORTED;
429 sdev_printk(KERN_WARNING, sdev,
430 "Capacity data has changed");
431 } else if (sshdr->asc == 0x2a)
432 sdev_printk(KERN_WARNING, sdev,
433 "Parameters changed");
436 if (evt_type != SDEV_EVT_MAXBITS) {
437 set_bit(evt_type, sdev->pending_events);
438 schedule_work(&sdev->event_work);
443 * scsi_check_sense - Examine scsi cmd sense
444 * @scmd: Cmd to have sense checked.
447 * SUCCESS or FAILED or NEEDS_RETRY or ADD_TO_MLQUEUE
450 * When a deferred error is detected the current command has
451 * not been executed and needs retrying.
453 static int scsi_check_sense(struct scsi_cmnd *scmd)
455 struct scsi_device *sdev = scmd->device;
456 struct scsi_sense_hdr sshdr;
458 if (! scsi_command_normalize_sense(scmd, &sshdr))
459 return FAILED; /* no valid sense data */
461 if (scmd->cmnd[0] == TEST_UNIT_READY && scmd->scsi_done != scsi_eh_done)
463 * nasty: for mid-layer issued TURs, we need to return the
464 * actual sense data without any recovery attempt. For eh
465 * issued ones, we need to try to recover and interpret
469 scsi_report_sense(sdev, &sshdr);
471 if (scsi_sense_is_deferred(&sshdr))
474 if (sdev->scsi_dh_data && sdev->scsi_dh_data->scsi_dh &&
475 sdev->scsi_dh_data->scsi_dh->check_sense) {
478 rc = sdev->scsi_dh_data->scsi_dh->check_sense(sdev, &sshdr);
479 if (rc != SCSI_RETURN_NOT_HANDLED)
481 /* handler does not care. Drop down to default handling */
485 * Previous logic looked for FILEMARK, EOM or ILI which are
486 * mainly associated with tapes and returned SUCCESS.
488 if (sshdr.response_code == 0x70) {
490 if (scmd->sense_buffer[2] & 0xe0)
494 * descriptor format: look for "stream commands sense data
495 * descriptor" (see SSC-3). Assume single sense data
496 * descriptor. Ignore ILI from SBC-2 READ LONG and WRITE LONG.
498 if ((sshdr.additional_length > 3) &&
499 (scmd->sense_buffer[8] == 0x4) &&
500 (scmd->sense_buffer[11] & 0xe0))
504 switch (sshdr.sense_key) {
507 case RECOVERED_ERROR:
508 return /* soft_error */ SUCCESS;
510 case ABORTED_COMMAND:
511 if (sshdr.asc == 0x10) /* DIF */
518 * if we are expecting a cc/ua because of a bus reset that we
519 * performed, treat this just as a retry. otherwise this is
520 * information that we should pass up to the upper-level driver
521 * so that we can deal with it there.
523 if (scmd->device->expecting_cc_ua) {
525 * Because some device does not queue unit
526 * attentions correctly, we carefully check
527 * additional sense code and qualifier so as
528 * not to squash media change unit attention.
530 if (sshdr.asc != 0x28 || sshdr.ascq != 0x00) {
531 scmd->device->expecting_cc_ua = 0;
536 * we might also expect a cc/ua if another LUN on the target
537 * reported a UA with an ASC/ASCQ of 3F 0E -
538 * REPORTED LUNS DATA HAS CHANGED.
540 if (scmd->device->sdev_target->expecting_lun_change &&
541 sshdr.asc == 0x3f && sshdr.ascq == 0x0e)
544 * if the device is in the process of becoming ready, we
547 if ((sshdr.asc == 0x04) && (sshdr.ascq == 0x01))
550 * if the device is not started, we need to wake
551 * the error handler to start the motor
553 if (scmd->device->allow_restart &&
554 (sshdr.asc == 0x04) && (sshdr.ascq == 0x02))
557 * Pass the UA upwards for a determination in the completion
562 /* these are not supported */
564 if (sshdr.asc == 0x27 && sshdr.ascq == 0x07) {
565 /* Thin provisioning hard threshold reached */
566 set_host_byte(scmd, DID_ALLOC_FAILURE);
570 case VOLUME_OVERFLOW:
573 set_host_byte(scmd, DID_TARGET_FAILURE);
577 if (sshdr.asc == 0x11 || /* UNRECOVERED READ ERR */
578 sshdr.asc == 0x13 || /* AMNF DATA FIELD */
579 sshdr.asc == 0x14) { /* RECORD NOT FOUND */
580 set_host_byte(scmd, DID_MEDIUM_ERROR);
586 if (scmd->device->retry_hwerror)
587 return ADD_TO_MLQUEUE;
589 set_host_byte(scmd, DID_TARGET_FAILURE);
591 case ILLEGAL_REQUEST:
592 if (sshdr.asc == 0x20 || /* Invalid command operation code */
593 sshdr.asc == 0x21 || /* Logical block address out of range */
594 sshdr.asc == 0x24 || /* Invalid field in cdb */
595 sshdr.asc == 0x26) { /* Parameter value invalid */
596 set_host_byte(scmd, DID_TARGET_FAILURE);
605 static void scsi_handle_queue_ramp_up(struct scsi_device *sdev)
607 struct scsi_host_template *sht = sdev->host->hostt;
608 struct scsi_device *tmp_sdev;
610 if (!sht->change_queue_depth ||
611 sdev->queue_depth >= sdev->max_queue_depth)
614 if (time_before(jiffies,
615 sdev->last_queue_ramp_up + sdev->queue_ramp_up_period))
618 if (time_before(jiffies,
619 sdev->last_queue_full_time + sdev->queue_ramp_up_period))
623 * Walk all devices of a target and do
626 shost_for_each_device(tmp_sdev, sdev->host) {
627 if (tmp_sdev->channel != sdev->channel ||
628 tmp_sdev->id != sdev->id ||
629 tmp_sdev->queue_depth == sdev->max_queue_depth)
632 * call back into LLD to increase queue_depth by one
633 * with ramp up reason code.
635 sht->change_queue_depth(tmp_sdev, tmp_sdev->queue_depth + 1,
636 SCSI_QDEPTH_RAMP_UP);
637 sdev->last_queue_ramp_up = jiffies;
641 static void scsi_handle_queue_full(struct scsi_device *sdev)
643 struct scsi_host_template *sht = sdev->host->hostt;
644 struct scsi_device *tmp_sdev;
646 if (!sht->change_queue_depth)
649 shost_for_each_device(tmp_sdev, sdev->host) {
650 if (tmp_sdev->channel != sdev->channel ||
651 tmp_sdev->id != sdev->id)
654 * We do not know the number of commands that were at
655 * the device when we got the queue full so we start
656 * from the highest possible value and work our way down.
658 sht->change_queue_depth(tmp_sdev, tmp_sdev->queue_depth - 1,
664 * scsi_eh_completed_normally - Disposition a eh cmd on return from LLD.
665 * @scmd: SCSI cmd to examine.
668 * This is *only* called when we are examining the status of commands
669 * queued during error recovery. the main difference here is that we
670 * don't allow for the possibility of retries here, and we are a lot
671 * more restrictive about what we consider acceptable.
673 static int scsi_eh_completed_normally(struct scsi_cmnd *scmd)
676 * first check the host byte, to see if there is anything in there
677 * that would indicate what we need to do.
679 if (host_byte(scmd->result) == DID_RESET) {
681 * rats. we are already in the error handler, so we now
682 * get to try and figure out what to do next. if the sense
683 * is valid, we have a pretty good idea of what to do.
684 * if not, we mark it as FAILED.
686 return scsi_check_sense(scmd);
688 if (host_byte(scmd->result) != DID_OK)
692 * next, check the message byte.
694 if (msg_byte(scmd->result) != COMMAND_COMPLETE)
698 * now, check the status byte to see if this indicates
701 switch (status_byte(scmd->result)) {
703 scsi_handle_queue_ramp_up(scmd->device);
704 case COMMAND_TERMINATED:
706 case CHECK_CONDITION:
707 return scsi_check_sense(scmd);
709 case INTERMEDIATE_GOOD:
710 case INTERMEDIATE_C_GOOD:
712 * who knows? FIXME(eric)
715 case RESERVATION_CONFLICT:
716 if (scmd->cmnd[0] == TEST_UNIT_READY)
717 /* it is a success, we probed the device and
720 /* otherwise, we failed to send the command */
723 scsi_handle_queue_full(scmd->device);
734 * scsi_eh_done - Completion function for error handling.
735 * @scmd: Cmd that is done.
737 static void scsi_eh_done(struct scsi_cmnd *scmd)
739 struct completion *eh_action;
741 SCSI_LOG_ERROR_RECOVERY(3,
742 printk("%s scmd: %p result: %x\n",
743 __func__, scmd, scmd->result));
745 eh_action = scmd->device->host->eh_action;
751 * scsi_try_host_reset - ask host adapter to reset itself
752 * @scmd: SCSI cmd to send host reset.
754 static int scsi_try_host_reset(struct scsi_cmnd *scmd)
758 struct Scsi_Host *host = scmd->device->host;
759 struct scsi_host_template *hostt = host->hostt;
761 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Snd Host RST\n",
764 if (!hostt->eh_host_reset_handler)
767 rtn = hostt->eh_host_reset_handler(scmd);
769 if (rtn == SUCCESS) {
770 if (!hostt->skip_settle_delay)
771 ssleep(HOST_RESET_SETTLE_TIME);
772 spin_lock_irqsave(host->host_lock, flags);
773 scsi_report_bus_reset(host, scmd_channel(scmd));
774 spin_unlock_irqrestore(host->host_lock, flags);
781 * scsi_try_bus_reset - ask host to perform a bus reset
782 * @scmd: SCSI cmd to send bus reset.
784 static int scsi_try_bus_reset(struct scsi_cmnd *scmd)
788 struct Scsi_Host *host = scmd->device->host;
789 struct scsi_host_template *hostt = host->hostt;
791 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Snd Bus RST\n",
794 if (!hostt->eh_bus_reset_handler)
797 rtn = hostt->eh_bus_reset_handler(scmd);
799 if (rtn == SUCCESS) {
800 if (!hostt->skip_settle_delay)
801 ssleep(BUS_RESET_SETTLE_TIME);
802 spin_lock_irqsave(host->host_lock, flags);
803 scsi_report_bus_reset(host, scmd_channel(scmd));
804 spin_unlock_irqrestore(host->host_lock, flags);
810 static void __scsi_report_device_reset(struct scsi_device *sdev, void *data)
813 sdev->expecting_cc_ua = 1;
817 * scsi_try_target_reset - Ask host to perform a target reset
818 * @scmd: SCSI cmd used to send a target reset
821 * There is no timeout for this operation. if this operation is
822 * unreliable for a given host, then the host itself needs to put a
823 * timer on it, and set the host back to a consistent state prior to
826 static int scsi_try_target_reset(struct scsi_cmnd *scmd)
830 struct Scsi_Host *host = scmd->device->host;
831 struct scsi_host_template *hostt = host->hostt;
833 if (!hostt->eh_target_reset_handler)
836 rtn = hostt->eh_target_reset_handler(scmd);
837 if (rtn == SUCCESS) {
838 spin_lock_irqsave(host->host_lock, flags);
839 __starget_for_each_device(scsi_target(scmd->device), NULL,
840 __scsi_report_device_reset);
841 spin_unlock_irqrestore(host->host_lock, flags);
848 * scsi_try_bus_device_reset - Ask host to perform a BDR on a dev
849 * @scmd: SCSI cmd used to send BDR
852 * There is no timeout for this operation. if this operation is
853 * unreliable for a given host, then the host itself needs to put a
854 * timer on it, and set the host back to a consistent state prior to
857 static int scsi_try_bus_device_reset(struct scsi_cmnd *scmd)
860 struct scsi_host_template *hostt = scmd->device->host->hostt;
862 if (!hostt->eh_device_reset_handler)
865 rtn = hostt->eh_device_reset_handler(scmd);
867 __scsi_report_device_reset(scmd->device, NULL);
871 static int scsi_try_to_abort_cmd(struct scsi_host_template *hostt, struct scsi_cmnd *scmd)
873 if (!hostt->eh_abort_handler)
876 return hostt->eh_abort_handler(scmd);
879 static void scsi_abort_eh_cmnd(struct scsi_cmnd *scmd)
881 if (scsi_try_to_abort_cmd(scmd->device->host->hostt, scmd) != SUCCESS)
882 if (scsi_try_bus_device_reset(scmd) != SUCCESS)
883 if (scsi_try_target_reset(scmd) != SUCCESS)
884 if (scsi_try_bus_reset(scmd) != SUCCESS)
885 scsi_try_host_reset(scmd);
889 * scsi_eh_prep_cmnd - Save a scsi command info as part of error recovery
890 * @scmd: SCSI command structure to hijack
891 * @ses: structure to save restore information
892 * @cmnd: CDB to send. Can be NULL if no new cmnd is needed
893 * @cmnd_size: size in bytes of @cmnd (must be <= BLK_MAX_CDB)
894 * @sense_bytes: size of sense data to copy. or 0 (if != 0 @cmnd is ignored)
896 * This function is used to save a scsi command information before re-execution
897 * as part of the error recovery process. If @sense_bytes is 0 the command
898 * sent must be one that does not transfer any data. If @sense_bytes != 0
899 * @cmnd is ignored and this functions sets up a REQUEST_SENSE command
900 * and cmnd buffers to read @sense_bytes into @scmd->sense_buffer.
902 void scsi_eh_prep_cmnd(struct scsi_cmnd *scmd, struct scsi_eh_save *ses,
903 unsigned char *cmnd, int cmnd_size, unsigned sense_bytes)
905 struct scsi_device *sdev = scmd->device;
908 * We need saved copies of a number of fields - this is because
909 * error handling may need to overwrite these with different values
910 * to run different commands, and once error handling is complete,
911 * we will need to restore these values prior to running the actual
914 ses->cmd_len = scmd->cmd_len;
915 ses->cmnd = scmd->cmnd;
916 ses->data_direction = scmd->sc_data_direction;
917 ses->sdb = scmd->sdb;
918 ses->next_rq = scmd->request->next_rq;
919 ses->result = scmd->result;
920 ses->underflow = scmd->underflow;
921 ses->prot_op = scmd->prot_op;
923 scmd->prot_op = SCSI_PROT_NORMAL;
925 scmd->cmnd = ses->eh_cmnd;
926 memset(scmd->cmnd, 0, BLK_MAX_CDB);
927 memset(&scmd->sdb, 0, sizeof(scmd->sdb));
928 scmd->request->next_rq = NULL;
932 scmd->sdb.length = min_t(unsigned, SCSI_SENSE_BUFFERSIZE,
934 sg_init_one(&ses->sense_sgl, scmd->sense_buffer,
936 scmd->sdb.table.sgl = &ses->sense_sgl;
937 scmd->sc_data_direction = DMA_FROM_DEVICE;
938 scmd->sdb.table.nents = 1;
939 scmd->cmnd[0] = REQUEST_SENSE;
940 scmd->cmnd[4] = scmd->sdb.length;
941 scmd->cmd_len = COMMAND_SIZE(scmd->cmnd[0]);
943 scmd->sc_data_direction = DMA_NONE;
945 BUG_ON(cmnd_size > BLK_MAX_CDB);
946 memcpy(scmd->cmnd, cmnd, cmnd_size);
947 scmd->cmd_len = COMMAND_SIZE(scmd->cmnd[0]);
953 if (sdev->scsi_level <= SCSI_2 && sdev->scsi_level != SCSI_UNKNOWN)
954 scmd->cmnd[1] = (scmd->cmnd[1] & 0x1f) |
955 (sdev->lun << 5 & 0xe0);
958 * Zero the sense buffer. The scsi spec mandates that any
959 * untransferred sense data should be interpreted as being zero.
961 memset(scmd->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE);
963 EXPORT_SYMBOL(scsi_eh_prep_cmnd);
966 * scsi_eh_restore_cmnd - Restore a scsi command info as part of error recovery
967 * @scmd: SCSI command structure to restore
968 * @ses: saved information from a coresponding call to scsi_eh_prep_cmnd
970 * Undo any damage done by above scsi_eh_prep_cmnd().
972 void scsi_eh_restore_cmnd(struct scsi_cmnd* scmd, struct scsi_eh_save *ses)
975 * Restore original data
977 scmd->cmd_len = ses->cmd_len;
978 scmd->cmnd = ses->cmnd;
979 scmd->sc_data_direction = ses->data_direction;
980 scmd->sdb = ses->sdb;
981 scmd->request->next_rq = ses->next_rq;
982 scmd->result = ses->result;
983 scmd->underflow = ses->underflow;
984 scmd->prot_op = ses->prot_op;
986 EXPORT_SYMBOL(scsi_eh_restore_cmnd);
989 * scsi_send_eh_cmnd - submit a scsi command as part of error recovery
990 * @scmd: SCSI command structure to hijack
992 * @cmnd_size: size in bytes of @cmnd
993 * @timeout: timeout for this request
994 * @sense_bytes: size of sense data to copy or 0
996 * This function is used to send a scsi command down to a target device
997 * as part of the error recovery process. See also scsi_eh_prep_cmnd() above.
1000 * SUCCESS or FAILED or NEEDS_RETRY
1002 static int scsi_send_eh_cmnd(struct scsi_cmnd *scmd, unsigned char *cmnd,
1003 int cmnd_size, int timeout, unsigned sense_bytes)
1005 struct scsi_device *sdev = scmd->device;
1006 struct Scsi_Host *shost = sdev->host;
1007 DECLARE_COMPLETION_ONSTACK(done);
1008 unsigned long timeleft = timeout;
1009 struct scsi_eh_save ses;
1010 const unsigned long stall_for = msecs_to_jiffies(100);
1014 scsi_eh_prep_cmnd(scmd, &ses, cmnd, cmnd_size, sense_bytes);
1015 shost->eh_action = &done;
1017 scsi_log_send(scmd);
1018 scmd->scsi_done = scsi_eh_done;
1019 rtn = shost->hostt->queuecommand(shost, scmd);
1021 if (timeleft > stall_for) {
1022 scsi_eh_restore_cmnd(scmd, &ses);
1023 timeleft -= stall_for;
1024 msleep(jiffies_to_msecs(stall_for));
1027 /* signal not to enter either branch of the if () below */
1031 timeleft = wait_for_completion_timeout(&done, timeout);
1035 shost->eh_action = NULL;
1037 scsi_log_completion(scmd, rtn);
1039 SCSI_LOG_ERROR_RECOVERY(3,
1040 printk("%s: scmd: %p, timeleft: %ld\n",
1041 __func__, scmd, timeleft));
1044 * If there is time left scsi_eh_done got called, and we will examine
1045 * the actual status codes to see whether the command actually did
1046 * complete normally, else if we have a zero return and no time left,
1047 * the command must still be pending, so abort it and return FAILED.
1048 * If we never actually managed to issue the command, because
1049 * ->queuecommand() kept returning non zero, use the rtn = FAILED
1050 * value above (so don't execute either branch of the if)
1053 rtn = scsi_eh_completed_normally(scmd);
1054 SCSI_LOG_ERROR_RECOVERY(3,
1055 printk("%s: scsi_eh_completed_normally %x\n",
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 shost_printk(KERN_INFO, shost,
1160 "skip %s, 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, printk("sense requested for %p"
1181 " result %x\n", scmd,
1183 SCSI_LOG_ERROR_RECOVERY(3, scsi_print_sense("bh", 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, printk("%s: scmd %p rtn %x\n",
1224 __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 shost_printk(KERN_INFO, sdev->host,
1269 "skip %s, 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 shost_printk(KERN_INFO, shost,
1322 "skip %s, past eh deadline\n",
1324 return list_empty(work_q);
1326 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: aborting cmd:"
1327 "0x%p\n", current->comm,
1329 rtn = scsi_try_to_abort_cmd(shost->hostt, scmd);
1330 if (rtn == FAILED) {
1331 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: aborting"
1336 list_splice_init(&check_list, work_q);
1337 return list_empty(work_q);
1339 scmd->eh_eflags &= ~SCSI_EH_CANCEL_CMD;
1340 if (rtn == FAST_IO_FAIL)
1341 scsi_eh_finish_cmd(scmd, done_q);
1343 list_move_tail(&scmd->eh_entry, &check_list);
1346 return scsi_eh_test_devices(&check_list, work_q, done_q, 0);
1350 * scsi_eh_try_stu - Send START_UNIT to device.
1351 * @scmd: &scsi_cmnd to send START_UNIT
1354 * 0 - Device is ready. 1 - Device NOT ready.
1356 static int scsi_eh_try_stu(struct scsi_cmnd *scmd)
1358 static unsigned char stu_command[6] = {START_STOP, 0, 0, 0, 1, 0};
1360 if (scmd->device->allow_restart) {
1361 int i, rtn = NEEDS_RETRY;
1363 for (i = 0; rtn == NEEDS_RETRY && i < 2; i++)
1364 rtn = scsi_send_eh_cmnd(scmd, stu_command, 6, scmd->device->request_queue->rq_timeout, 0);
1374 * scsi_eh_stu - send START_UNIT if needed
1375 * @shost: &scsi host being recovered.
1376 * @work_q: &list_head for pending commands.
1377 * @done_q: &list_head for processed commands.
1380 * If commands are failing due to not ready, initializing command required,
1381 * try revalidating the device, which will end up sending a start unit.
1383 static int scsi_eh_stu(struct Scsi_Host *shost,
1384 struct list_head *work_q,
1385 struct list_head *done_q)
1387 struct scsi_cmnd *scmd, *stu_scmd, *next;
1388 struct scsi_device *sdev;
1390 shost_for_each_device(sdev, shost) {
1391 if (scsi_host_eh_past_deadline(shost)) {
1392 SCSI_LOG_ERROR_RECOVERY(3,
1393 shost_printk(KERN_INFO, shost,
1394 "skip %s, past eh deadline\n",
1399 list_for_each_entry(scmd, work_q, eh_entry)
1400 if (scmd->device == sdev && SCSI_SENSE_VALID(scmd) &&
1401 scsi_check_sense(scmd) == FAILED ) {
1409 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending START_UNIT to sdev:"
1410 " 0x%p\n", current->comm, sdev));
1412 if (!scsi_eh_try_stu(stu_scmd)) {
1413 if (!scsi_device_online(sdev) ||
1414 !scsi_eh_tur(stu_scmd)) {
1415 list_for_each_entry_safe(scmd, next,
1417 if (scmd->device == sdev &&
1418 scsi_eh_action(scmd, SUCCESS) == SUCCESS)
1419 scsi_eh_finish_cmd(scmd, done_q);
1423 SCSI_LOG_ERROR_RECOVERY(3,
1424 printk("%s: START_UNIT failed to sdev:"
1425 " 0x%p\n", current->comm, sdev));
1429 return list_empty(work_q);
1434 * scsi_eh_bus_device_reset - send bdr if needed
1435 * @shost: scsi host being recovered.
1436 * @work_q: &list_head for pending commands.
1437 * @done_q: &list_head for processed commands.
1440 * Try a bus device reset. Still, look to see whether we have multiple
1441 * devices that are jammed or not - if we have multiple devices, it
1442 * makes no sense to try bus_device_reset - we really would need to try
1443 * a bus_reset instead.
1445 static int scsi_eh_bus_device_reset(struct Scsi_Host *shost,
1446 struct list_head *work_q,
1447 struct list_head *done_q)
1449 struct scsi_cmnd *scmd, *bdr_scmd, *next;
1450 struct scsi_device *sdev;
1453 shost_for_each_device(sdev, shost) {
1454 if (scsi_host_eh_past_deadline(shost)) {
1455 SCSI_LOG_ERROR_RECOVERY(3,
1456 shost_printk(KERN_INFO, shost,
1457 "skip %s, past eh deadline\n",
1462 list_for_each_entry(scmd, work_q, eh_entry)
1463 if (scmd->device == sdev) {
1471 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending BDR sdev:"
1472 " 0x%p\n", current->comm,
1474 rtn = scsi_try_bus_device_reset(bdr_scmd);
1475 if (rtn == SUCCESS || rtn == FAST_IO_FAIL) {
1476 if (!scsi_device_online(sdev) ||
1477 rtn == FAST_IO_FAIL ||
1478 !scsi_eh_tur(bdr_scmd)) {
1479 list_for_each_entry_safe(scmd, next,
1481 if (scmd->device == sdev &&
1482 scsi_eh_action(scmd, rtn) != FAILED)
1483 scsi_eh_finish_cmd(scmd,
1488 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: BDR"
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 "skip %s, 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, printk("%s: Sending target reset "
1538 current->comm, id));
1539 rtn = scsi_try_target_reset(scmd);
1540 if (rtn != SUCCESS && rtn != FAST_IO_FAIL)
1541 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Target reset"
1544 current->comm, id));
1545 list_for_each_entry_safe(scmd, next, &tmp_list, eh_entry) {
1546 if (scmd_id(scmd) != id)
1550 list_move_tail(&scmd->eh_entry, &check_list);
1551 else if (rtn == FAST_IO_FAIL)
1552 scsi_eh_finish_cmd(scmd, done_q);
1554 /* push back on work queue for further processing */
1555 list_move(&scmd->eh_entry, work_q);
1559 return scsi_eh_test_devices(&check_list, work_q, done_q, 0);
1563 * scsi_eh_bus_reset - send a bus reset
1564 * @shost: &scsi host being recovered.
1565 * @work_q: &list_head for pending commands.
1566 * @done_q: &list_head for processed commands.
1568 static int scsi_eh_bus_reset(struct Scsi_Host *shost,
1569 struct list_head *work_q,
1570 struct list_head *done_q)
1572 struct scsi_cmnd *scmd, *chan_scmd, *next;
1573 LIST_HEAD(check_list);
1574 unsigned int channel;
1578 * we really want to loop over the various channels, and do this on
1579 * a channel by channel basis. we should also check to see if any
1580 * of the failed commands are on soft_reset devices, and if so, skip
1584 for (channel = 0; channel <= shost->max_channel; channel++) {
1585 if (scsi_host_eh_past_deadline(shost)) {
1586 list_splice_init(&check_list, work_q);
1587 SCSI_LOG_ERROR_RECOVERY(3,
1588 shost_printk(KERN_INFO, shost,
1589 "skip %s, past eh deadline\n",
1591 return list_empty(work_q);
1595 list_for_each_entry(scmd, work_q, eh_entry) {
1596 if (channel == scmd_channel(scmd)) {
1600 * FIXME add back in some support for
1601 * soft_reset devices.
1608 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending BRST chan:"
1609 " %d\n", current->comm,
1611 rtn = scsi_try_bus_reset(chan_scmd);
1612 if (rtn == SUCCESS || rtn == FAST_IO_FAIL) {
1613 list_for_each_entry_safe(scmd, next, work_q, eh_entry) {
1614 if (channel == scmd_channel(scmd)) {
1615 if (rtn == FAST_IO_FAIL)
1616 scsi_eh_finish_cmd(scmd,
1619 list_move_tail(&scmd->eh_entry,
1624 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: BRST"
1625 " failed chan: %d\n",
1630 return scsi_eh_test_devices(&check_list, work_q, done_q, 0);
1634 * scsi_eh_host_reset - send a host reset
1635 * @work_q: list_head for processed commands.
1636 * @done_q: list_head for processed commands.
1638 static int scsi_eh_host_reset(struct list_head *work_q,
1639 struct list_head *done_q)
1641 struct scsi_cmnd *scmd, *next;
1642 LIST_HEAD(check_list);
1645 if (!list_empty(work_q)) {
1646 scmd = list_entry(work_q->next,
1647 struct scsi_cmnd, eh_entry);
1649 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending HRST\n"
1652 rtn = scsi_try_host_reset(scmd);
1653 if (rtn == SUCCESS) {
1654 list_splice_init(work_q, &check_list);
1655 } else if (rtn == FAST_IO_FAIL) {
1656 list_for_each_entry_safe(scmd, next, work_q, eh_entry) {
1657 scsi_eh_finish_cmd(scmd, done_q);
1660 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: HRST"
1665 return scsi_eh_test_devices(&check_list, work_q, done_q, 1);
1669 * scsi_eh_offline_sdevs - offline scsi devices that fail to recover
1670 * @work_q: list_head for processed commands.
1671 * @done_q: list_head for processed commands.
1673 static void scsi_eh_offline_sdevs(struct list_head *work_q,
1674 struct list_head *done_q)
1676 struct scsi_cmnd *scmd, *next;
1678 list_for_each_entry_safe(scmd, next, work_q, eh_entry) {
1679 sdev_printk(KERN_INFO, scmd->device, "Device offlined - "
1680 "not ready after error recovery\n");
1681 scsi_device_set_state(scmd->device, SDEV_OFFLINE);
1682 if (scmd->eh_eflags & SCSI_EH_CANCEL_CMD) {
1684 * FIXME: Handle lost cmds.
1687 scsi_eh_finish_cmd(scmd, done_q);
1693 * scsi_noretry_cmd - determine if command should be failed fast
1694 * @scmd: SCSI cmd to examine.
1696 int scsi_noretry_cmd(struct scsi_cmnd *scmd)
1698 switch (host_byte(scmd->result)) {
1704 return (scmd->request->cmd_flags & REQ_FAILFAST_TRANSPORT);
1706 return (scmd->request->cmd_flags & REQ_FAILFAST_DEV);
1708 if (msg_byte(scmd->result) == COMMAND_COMPLETE &&
1709 status_byte(scmd->result) == RESERVATION_CONFLICT)
1712 case DID_SOFT_ERROR:
1713 return (scmd->request->cmd_flags & REQ_FAILFAST_DRIVER);
1716 if (status_byte(scmd->result) != CHECK_CONDITION)
1721 * assume caller has checked sense and determined
1722 * the check condition was retryable.
1724 if (scmd->request->cmd_flags & REQ_FAILFAST_DEV ||
1725 scmd->request->cmd_type == REQ_TYPE_BLOCK_PC)
1732 * scsi_decide_disposition - Disposition a cmd on return from LLD.
1733 * @scmd: SCSI cmd to examine.
1736 * This is *only* called when we are examining the status after sending
1737 * out the actual data command. any commands that are queued for error
1738 * recovery (e.g. test_unit_ready) do *not* come through here.
1740 * When this routine returns failed, it means the error handler thread
1741 * is woken. In cases where the error code indicates an error that
1742 * doesn't require the error handler read (i.e. we don't need to
1743 * abort/reset), this function should return SUCCESS.
1745 int scsi_decide_disposition(struct scsi_cmnd *scmd)
1750 * if the device is offline, then we clearly just pass the result back
1751 * up to the top level.
1753 if (!scsi_device_online(scmd->device)) {
1754 SCSI_LOG_ERROR_RECOVERY(5, printk("%s: device offline - report"
1761 * first check the host byte, to see if there is anything in there
1762 * that would indicate what we need to do.
1764 switch (host_byte(scmd->result)) {
1765 case DID_PASSTHROUGH:
1767 * no matter what, pass this through to the upper layer.
1768 * nuke this special code so that it looks like we are saying
1771 scmd->result &= 0xff00ffff;
1775 * looks good. drop through, and check the next byte.
1779 if (scmd->eh_eflags & SCSI_EH_ABORT_SCHEDULED) {
1780 scmd->result |= DID_TIME_OUT << 16;
1783 case DID_NO_CONNECT:
1784 case DID_BAD_TARGET:
1786 * note - this means that we just report the status back
1787 * to the top level driver, not that we actually think
1788 * that it indicates SUCCESS.
1792 * when the low level driver returns did_soft_error,
1793 * it is responsible for keeping an internal retry counter
1794 * in order to avoid endless loops (db)
1796 * actually this is a bug in this function here. we should
1797 * be mindful of the maximum number of retries specified
1798 * and not get stuck in a loop.
1800 case DID_SOFT_ERROR:
1806 return ADD_TO_MLQUEUE;
1807 case DID_TRANSPORT_DISRUPTED:
1809 * LLD/transport was disrupted during processing of the IO.
1810 * The transport class is now blocked/blocking,
1811 * and the transport will decide what to do with the IO
1812 * based on its timers and recovery capablilities if
1813 * there are enough retries.
1816 case DID_TRANSPORT_FAILFAST:
1818 * The transport decided to failfast the IO (most likely
1819 * the fast io fail tmo fired), so send IO directly upwards.
1823 if (msg_byte(scmd->result) == COMMAND_COMPLETE &&
1824 status_byte(scmd->result) == RESERVATION_CONFLICT)
1826 * execute reservation conflict processing code
1836 * when we scan the bus, we get timeout messages for
1837 * these commands if there is no device available.
1838 * other hosts report did_no_connect for the same thing.
1840 if ((scmd->cmnd[0] == TEST_UNIT_READY ||
1841 scmd->cmnd[0] == INQUIRY)) {
1853 * next, check the message byte.
1855 if (msg_byte(scmd->result) != COMMAND_COMPLETE)
1859 * check the status byte to see if this indicates anything special.
1861 switch (status_byte(scmd->result)) {
1863 scsi_handle_queue_full(scmd->device);
1865 * the case of trying to send too many commands to a
1866 * tagged queueing device.
1870 * device can't talk to us at the moment. Should only
1871 * occur (SAM-3) when the task queue is empty, so will cause
1872 * the empty queue handling to trigger a stall in the
1875 return ADD_TO_MLQUEUE;
1877 if (scmd->cmnd[0] == REPORT_LUNS)
1878 scmd->device->sdev_target->expecting_lun_change = 0;
1879 scsi_handle_queue_ramp_up(scmd->device);
1880 case COMMAND_TERMINATED:
1884 case CHECK_CONDITION:
1885 rtn = scsi_check_sense(scmd);
1886 if (rtn == NEEDS_RETRY)
1888 /* if rtn == FAILED, we have no sense information;
1889 * returning FAILED will wake the error handler thread
1890 * to collect the sense and redo the decide
1893 case CONDITION_GOOD:
1894 case INTERMEDIATE_GOOD:
1895 case INTERMEDIATE_C_GOOD:
1898 * who knows? FIXME(eric)
1902 case RESERVATION_CONFLICT:
1903 sdev_printk(KERN_INFO, scmd->device,
1904 "reservation conflict\n");
1905 set_host_byte(scmd, DID_NEXUS_FAILURE);
1906 return SUCCESS; /* causes immediate i/o error */
1914 /* we requeue for retry because the error was retryable, and
1915 * the request was not marked fast fail. Note that above,
1916 * even if the request is marked fast fail, we still requeue
1917 * for queue congestion conditions (QUEUE_FULL or BUSY) */
1918 if ((++scmd->retries) <= scmd->allowed
1919 && !scsi_noretry_cmd(scmd)) {
1923 * no more retries - report this one back to upper level.
1929 static void eh_lock_door_done(struct request *req, int uptodate)
1931 __blk_put_request(req->q, req);
1935 * scsi_eh_lock_door - Prevent medium removal for the specified device
1936 * @sdev: SCSI device to prevent medium removal
1939 * We must be called from process context.
1942 * We queue up an asynchronous "ALLOW MEDIUM REMOVAL" request on the
1943 * head of the devices request queue, and continue.
1945 static void scsi_eh_lock_door(struct scsi_device *sdev)
1947 struct request *req;
1950 * blk_get_request with GFP_KERNEL (__GFP_WAIT) sleeps until a
1951 * request becomes available
1953 req = blk_get_request(sdev->request_queue, READ, GFP_KERNEL);
1955 blk_rq_set_block_pc(req);
1957 req->cmd[0] = ALLOW_MEDIUM_REMOVAL;
1961 req->cmd[4] = SCSI_REMOVAL_PREVENT;
1964 req->cmd_len = COMMAND_SIZE(req->cmd[0]);
1966 req->cmd_flags |= REQ_QUIET;
1967 req->timeout = 10 * HZ;
1970 blk_execute_rq_nowait(req->q, NULL, req, 1, eh_lock_door_done);
1974 * scsi_restart_operations - restart io operations to the specified host.
1975 * @shost: Host we are restarting.
1978 * When we entered the error handler, we blocked all further i/o to
1979 * this device. we need to 'reverse' this process.
1981 static void scsi_restart_operations(struct Scsi_Host *shost)
1983 struct scsi_device *sdev;
1984 unsigned long flags;
1987 * If the door was locked, we need to insert a door lock request
1988 * onto the head of the SCSI request queue for the device. There
1989 * is no point trying to lock the door of an off-line device.
1991 shost_for_each_device(sdev, shost) {
1992 if (scsi_device_online(sdev) && sdev->locked)
1993 scsi_eh_lock_door(sdev);
1997 * next free up anything directly waiting upon the host. this
1998 * will be requests for character device operations, and also for
1999 * ioctls to queued block devices.
2001 SCSI_LOG_ERROR_RECOVERY(3,
2002 printk("scsi_eh_%d waking up host to restart\n",
2005 spin_lock_irqsave(shost->host_lock, flags);
2006 if (scsi_host_set_state(shost, SHOST_RUNNING))
2007 if (scsi_host_set_state(shost, SHOST_CANCEL))
2008 BUG_ON(scsi_host_set_state(shost, SHOST_DEL));
2009 spin_unlock_irqrestore(shost->host_lock, flags);
2011 wake_up(&shost->host_wait);
2014 * finally we need to re-initiate requests that may be pending. we will
2015 * have had everything blocked while error handling is taking place, and
2016 * now that error recovery is done, we will need to ensure that these
2017 * requests are started.
2019 scsi_run_host_queues(shost);
2022 * if eh is active and host_eh_scheduled is pending we need to re-run
2023 * recovery. we do this check after scsi_run_host_queues() to allow
2024 * everything pent up since the last eh run a chance to make forward
2025 * progress before we sync again. Either we'll immediately re-run
2026 * recovery or scsi_device_unbusy() will wake us again when these
2027 * pending commands complete.
2029 spin_lock_irqsave(shost->host_lock, flags);
2030 if (shost->host_eh_scheduled)
2031 if (scsi_host_set_state(shost, SHOST_RECOVERY))
2032 WARN_ON(scsi_host_set_state(shost, SHOST_CANCEL_RECOVERY));
2033 spin_unlock_irqrestore(shost->host_lock, flags);
2037 * scsi_eh_ready_devs - check device ready state and recover if not.
2038 * @shost: host to be recovered.
2039 * @work_q: &list_head for pending commands.
2040 * @done_q: &list_head for processed commands.
2042 void scsi_eh_ready_devs(struct Scsi_Host *shost,
2043 struct list_head *work_q,
2044 struct list_head *done_q)
2046 if (!scsi_eh_stu(shost, work_q, done_q))
2047 if (!scsi_eh_bus_device_reset(shost, work_q, done_q))
2048 if (!scsi_eh_target_reset(shost, work_q, done_q))
2049 if (!scsi_eh_bus_reset(shost, work_q, done_q))
2050 if (!scsi_eh_host_reset(work_q, done_q))
2051 scsi_eh_offline_sdevs(work_q,
2054 EXPORT_SYMBOL_GPL(scsi_eh_ready_devs);
2057 * scsi_eh_flush_done_q - finish processed commands or retry them.
2058 * @done_q: list_head of processed commands.
2060 void scsi_eh_flush_done_q(struct list_head *done_q)
2062 struct scsi_cmnd *scmd, *next;
2064 list_for_each_entry_safe(scmd, next, done_q, eh_entry) {
2065 list_del_init(&scmd->eh_entry);
2066 if (scsi_device_online(scmd->device) &&
2067 !scsi_noretry_cmd(scmd) &&
2068 (++scmd->retries <= scmd->allowed)) {
2069 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: flush"
2073 scsi_queue_insert(scmd, SCSI_MLQUEUE_EH_RETRY);
2076 * If just we got sense for the device (called
2077 * scsi_eh_get_sense), scmd->result is already
2078 * set, do not set DRIVER_TIMEOUT.
2081 scmd->result |= (DRIVER_TIMEOUT << 24);
2082 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: flush finish"
2084 current->comm, scmd));
2085 scsi_finish_command(scmd);
2089 EXPORT_SYMBOL(scsi_eh_flush_done_q);
2092 * scsi_unjam_host - Attempt to fix a host which has a cmd that failed.
2093 * @shost: Host to unjam.
2096 * When we come in here, we *know* that all commands on the bus have
2097 * either completed, failed or timed out. we also know that no further
2098 * commands are being sent to the host, so things are relatively quiet
2099 * and we have freedom to fiddle with things as we wish.
2101 * This is only the *default* implementation. it is possible for
2102 * individual drivers to supply their own version of this function, and
2103 * if the maintainer wishes to do this, it is strongly suggested that
2104 * this function be taken as a template and modified. this function
2105 * was designed to correctly handle problems for about 95% of the
2106 * different cases out there, and it should always provide at least a
2107 * reasonable amount of error recovery.
2109 * Any command marked 'failed' or 'timeout' must eventually have
2110 * scsi_finish_cmd() called for it. we do all of the retry stuff
2111 * here, so when we restart the host after we return it should have an
2114 static void scsi_unjam_host(struct Scsi_Host *shost)
2116 unsigned long flags;
2117 LIST_HEAD(eh_work_q);
2118 LIST_HEAD(eh_done_q);
2120 spin_lock_irqsave(shost->host_lock, flags);
2121 list_splice_init(&shost->eh_cmd_q, &eh_work_q);
2122 spin_unlock_irqrestore(shost->host_lock, flags);
2124 SCSI_LOG_ERROR_RECOVERY(1, scsi_eh_prt_fail_stats(shost, &eh_work_q));
2126 if (!scsi_eh_get_sense(&eh_work_q, &eh_done_q))
2127 if (!scsi_eh_abort_cmds(&eh_work_q, &eh_done_q))
2128 scsi_eh_ready_devs(shost, &eh_work_q, &eh_done_q);
2130 spin_lock_irqsave(shost->host_lock, flags);
2131 if (shost->eh_deadline != -1)
2132 shost->last_reset = 0;
2133 spin_unlock_irqrestore(shost->host_lock, flags);
2134 scsi_eh_flush_done_q(&eh_done_q);
2138 * scsi_error_handler - SCSI error handler thread
2139 * @data: Host for which we are running.
2142 * This is the main error handling loop. This is run as a kernel thread
2143 * for every SCSI host and handles all error handling activity.
2145 int scsi_error_handler(void *data)
2147 struct Scsi_Host *shost = data;
2150 * We use TASK_INTERRUPTIBLE so that the thread is not
2151 * counted against the load average as a running process.
2152 * We never actually get interrupted because kthread_run
2153 * disables signal delivery for the created thread.
2155 while (!kthread_should_stop()) {
2156 set_current_state(TASK_INTERRUPTIBLE);
2157 if ((shost->host_failed == 0 && shost->host_eh_scheduled == 0) ||
2158 shost->host_failed != shost->host_busy) {
2159 SCSI_LOG_ERROR_RECOVERY(1,
2160 printk("scsi_eh_%d: sleeping\n",
2166 __set_current_state(TASK_RUNNING);
2167 SCSI_LOG_ERROR_RECOVERY(1,
2168 printk("scsi_eh_%d: waking up %d/%d/%d\n",
2169 shost->host_no, shost->host_eh_scheduled,
2170 shost->host_failed, shost->host_busy));
2173 * We have a host that is failing for some reason. Figure out
2174 * what we need to do to get it up and online again (if we can).
2175 * If we fail, we end up taking the thing offline.
2177 if (!shost->eh_noresume && scsi_autopm_get_host(shost) != 0) {
2178 SCSI_LOG_ERROR_RECOVERY(1,
2179 printk(KERN_ERR "Error handler scsi_eh_%d "
2180 "unable to autoresume\n",
2185 if (shost->transportt->eh_strategy_handler)
2186 shost->transportt->eh_strategy_handler(shost);
2188 scsi_unjam_host(shost);
2191 * Note - if the above fails completely, the action is to take
2192 * individual devices offline and flush the queue of any
2193 * outstanding requests that may have been pending. When we
2194 * restart, we restart any I/O to any other devices on the bus
2195 * which are still online.
2197 scsi_restart_operations(shost);
2198 if (!shost->eh_noresume)
2199 scsi_autopm_put_host(shost);
2201 __set_current_state(TASK_RUNNING);
2203 SCSI_LOG_ERROR_RECOVERY(1,
2204 printk("Error handler scsi_eh_%d exiting\n", shost->host_no));
2205 shost->ehandler = NULL;
2210 * Function: scsi_report_bus_reset()
2212 * Purpose: Utility function used by low-level drivers to report that
2213 * they have observed a bus reset on the bus being handled.
2215 * Arguments: shost - Host in question
2216 * channel - channel on which reset was observed.
2220 * Lock status: Host lock must be held.
2222 * Notes: This only needs to be called if the reset is one which
2223 * originates from an unknown location. Resets originated
2224 * by the mid-level itself don't need to call this, but there
2225 * should be no harm.
2227 * The main purpose of this is to make sure that a CHECK_CONDITION
2228 * is properly treated.
2230 void scsi_report_bus_reset(struct Scsi_Host *shost, int channel)
2232 struct scsi_device *sdev;
2234 __shost_for_each_device(sdev, shost) {
2235 if (channel == sdev_channel(sdev))
2236 __scsi_report_device_reset(sdev, NULL);
2239 EXPORT_SYMBOL(scsi_report_bus_reset);
2242 * Function: scsi_report_device_reset()
2244 * Purpose: Utility function used by low-level drivers to report that
2245 * they have observed a device reset on the device being handled.
2247 * Arguments: shost - Host in question
2248 * channel - channel on which reset was observed
2249 * target - target on which reset was observed
2253 * Lock status: Host lock must be held
2255 * Notes: This only needs to be called if the reset is one which
2256 * originates from an unknown location. Resets originated
2257 * by the mid-level itself don't need to call this, but there
2258 * should be no harm.
2260 * The main purpose of this is to make sure that a CHECK_CONDITION
2261 * is properly treated.
2263 void scsi_report_device_reset(struct Scsi_Host *shost, int channel, int target)
2265 struct scsi_device *sdev;
2267 __shost_for_each_device(sdev, shost) {
2268 if (channel == sdev_channel(sdev) &&
2269 target == sdev_id(sdev))
2270 __scsi_report_device_reset(sdev, NULL);
2273 EXPORT_SYMBOL(scsi_report_device_reset);
2276 scsi_reset_provider_done_command(struct scsi_cmnd *scmd)
2281 * Function: scsi_reset_provider
2283 * Purpose: Send requested reset to a bus or device at any phase.
2285 * Arguments: device - device to send reset to
2286 * flag - reset type (see scsi.h)
2288 * Returns: SUCCESS/FAILURE.
2290 * Notes: This is used by the SCSI Generic driver to provide
2291 * Bus/Device reset capability.
2294 scsi_reset_provider(struct scsi_device *dev, int flag)
2296 struct scsi_cmnd *scmd;
2297 struct Scsi_Host *shost = dev->host;
2299 unsigned long flags;
2302 if (scsi_autopm_get_host(shost) < 0)
2305 if (!get_device(&dev->sdev_gendev)) {
2307 goto out_put_autopm_host;
2310 scmd = scsi_get_command(dev, GFP_KERNEL);
2313 put_device(&dev->sdev_gendev);
2314 goto out_put_autopm_host;
2317 blk_rq_init(NULL, &req);
2318 scmd->request = &req;
2320 scmd->cmnd = req.cmd;
2322 scmd->scsi_done = scsi_reset_provider_done_command;
2323 memset(&scmd->sdb, 0, sizeof(scmd->sdb));
2327 scmd->sc_data_direction = DMA_BIDIRECTIONAL;
2329 spin_lock_irqsave(shost->host_lock, flags);
2330 shost->tmf_in_progress = 1;
2331 spin_unlock_irqrestore(shost->host_lock, flags);
2334 case SCSI_TRY_RESET_DEVICE:
2335 rtn = scsi_try_bus_device_reset(scmd);
2339 case SCSI_TRY_RESET_TARGET:
2340 rtn = scsi_try_target_reset(scmd);
2344 case SCSI_TRY_RESET_BUS:
2345 rtn = scsi_try_bus_reset(scmd);
2349 case SCSI_TRY_RESET_HOST:
2350 rtn = scsi_try_host_reset(scmd);
2356 spin_lock_irqsave(shost->host_lock, flags);
2357 shost->tmf_in_progress = 0;
2358 spin_unlock_irqrestore(shost->host_lock, flags);
2361 * be sure to wake up anyone who was sleeping or had their queue
2362 * suspended while we performed the TMF.
2364 SCSI_LOG_ERROR_RECOVERY(3,
2365 printk("%s: waking up host to restart after TMF\n",
2368 wake_up(&shost->host_wait);
2370 scsi_run_host_queues(shost);
2372 scsi_next_command(scmd);
2373 out_put_autopm_host:
2374 scsi_autopm_put_host(shost);
2377 EXPORT_SYMBOL(scsi_reset_provider);
2380 * scsi_normalize_sense - normalize main elements from either fixed or
2381 * descriptor sense data format into a common format.
2383 * @sense_buffer: byte array containing sense data returned by device
2384 * @sb_len: number of valid bytes in sense_buffer
2385 * @sshdr: pointer to instance of structure that common
2386 * elements are written to.
2389 * The "main elements" from sense data are: response_code, sense_key,
2390 * asc, ascq and additional_length (only for descriptor format).
2392 * Typically this function can be called after a device has
2393 * responded to a SCSI command with the CHECK_CONDITION status.
2396 * 1 if valid sense data information found, else 0;
2398 int scsi_normalize_sense(const u8 *sense_buffer, int sb_len,
2399 struct scsi_sense_hdr *sshdr)
2401 if (!sense_buffer || !sb_len)
2404 memset(sshdr, 0, sizeof(struct scsi_sense_hdr));
2406 sshdr->response_code = (sense_buffer[0] & 0x7f);
2408 if (!scsi_sense_valid(sshdr))
2411 if (sshdr->response_code >= 0x72) {
2416 sshdr->sense_key = (sense_buffer[1] & 0xf);
2418 sshdr->asc = sense_buffer[2];
2420 sshdr->ascq = sense_buffer[3];
2422 sshdr->additional_length = sense_buffer[7];
2428 sshdr->sense_key = (sense_buffer[2] & 0xf);
2430 sb_len = (sb_len < (sense_buffer[7] + 8)) ?
2431 sb_len : (sense_buffer[7] + 8);
2433 sshdr->asc = sense_buffer[12];
2435 sshdr->ascq = sense_buffer[13];
2441 EXPORT_SYMBOL(scsi_normalize_sense);
2443 int scsi_command_normalize_sense(struct scsi_cmnd *cmd,
2444 struct scsi_sense_hdr *sshdr)
2446 return scsi_normalize_sense(cmd->sense_buffer,
2447 SCSI_SENSE_BUFFERSIZE, sshdr);
2449 EXPORT_SYMBOL(scsi_command_normalize_sense);
2452 * scsi_sense_desc_find - search for a given descriptor type in descriptor sense data format.
2453 * @sense_buffer: byte array of descriptor format sense data
2454 * @sb_len: number of valid bytes in sense_buffer
2455 * @desc_type: value of descriptor type to find
2456 * (e.g. 0 -> information)
2459 * only valid when sense data is in descriptor format
2462 * pointer to start of (first) descriptor if found else NULL
2464 const u8 * scsi_sense_desc_find(const u8 * sense_buffer, int sb_len,
2467 int add_sen_len, add_len, desc_len, k;
2470 if ((sb_len < 8) || (0 == (add_sen_len = sense_buffer[7])))
2472 if ((sense_buffer[0] < 0x72) || (sense_buffer[0] > 0x73))
2474 add_sen_len = (add_sen_len < (sb_len - 8)) ?
2475 add_sen_len : (sb_len - 8);
2476 descp = &sense_buffer[8];
2477 for (desc_len = 0, k = 0; k < add_sen_len; k += desc_len) {
2479 add_len = (k < (add_sen_len - 1)) ? descp[1]: -1;
2480 desc_len = add_len + 2;
2481 if (descp[0] == desc_type)
2483 if (add_len < 0) // short descriptor ??
2488 EXPORT_SYMBOL(scsi_sense_desc_find);
2491 * scsi_get_sense_info_fld - get information field from sense data (either fixed or descriptor format)
2492 * @sense_buffer: byte array of sense data
2493 * @sb_len: number of valid bytes in sense_buffer
2494 * @info_out: pointer to 64 integer where 8 or 4 byte information
2495 * field will be placed if found.
2498 * 1 if information field found, 0 if not found.
2500 int scsi_get_sense_info_fld(const u8 * sense_buffer, int sb_len,
2509 switch (sense_buffer[0] & 0x7f) {
2512 if (sense_buffer[0] & 0x80) {
2513 *info_out = (sense_buffer[3] << 24) +
2514 (sense_buffer[4] << 16) +
2515 (sense_buffer[5] << 8) + sense_buffer[6];
2521 ucp = scsi_sense_desc_find(sense_buffer, sb_len,
2523 if (ucp && (0xa == ucp[1])) {
2525 for (j = 0; j < 8; ++j) {
2538 EXPORT_SYMBOL(scsi_get_sense_info_fld);
2541 * scsi_build_sense_buffer - build sense data in a buffer
2542 * @desc: Sense format (non zero == descriptor format,
2543 * 0 == fixed format)
2544 * @buf: Where to build sense data
2546 * @asc: Additional sense code
2547 * @ascq: Additional sense code qualifier
2550 void scsi_build_sense_buffer(int desc, u8 *buf, u8 key, u8 asc, u8 ascq)
2553 buf[0] = 0x72; /* descriptor, current */
2559 buf[0] = 0x70; /* fixed, current */
2566 EXPORT_SYMBOL(scsi_build_sense_buffer);