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/timer.h>
20 #include <linux/string.h>
21 #include <linux/slab.h>
22 #include <linux/kernel.h>
23 #include <linux/kthread.h>
24 #include <linux/interrupt.h>
25 #include <linux/blkdev.h>
26 #include <linux/delay.h>
28 #include <scsi/scsi.h>
29 #include <scsi/scsi_cmnd.h>
30 #include <scsi/scsi_dbg.h>
31 #include <scsi/scsi_device.h>
32 #include <scsi/scsi_eh.h>
33 #include <scsi/scsi_transport.h>
34 #include <scsi/scsi_host.h>
35 #include <scsi/scsi_ioctl.h>
37 #include "scsi_priv.h"
38 #include "scsi_logging.h"
40 #define SENSE_TIMEOUT (10*HZ)
41 #define START_UNIT_TIMEOUT (30*HZ)
44 * These should *probably* be handled by the host itself.
45 * Since it is allowed to sleep, it probably should.
47 #define BUS_RESET_SETTLE_TIME (10)
48 #define HOST_RESET_SETTLE_TIME (10)
50 /* called with shost->host_lock held */
51 void scsi_eh_wakeup(struct Scsi_Host *shost)
53 if (shost->host_busy == shost->host_failed) {
54 wake_up_process(shost->ehandler);
55 SCSI_LOG_ERROR_RECOVERY(5,
56 printk("Waking error handler thread\n"));
61 * scsi_schedule_eh - schedule EH for SCSI host
62 * @shost: SCSI host to invoke error handling on.
64 * Schedule SCSI EH without scmd.
66 void scsi_schedule_eh(struct Scsi_Host *shost)
70 spin_lock_irqsave(shost->host_lock, flags);
72 if (scsi_host_set_state(shost, SHOST_RECOVERY) == 0 ||
73 scsi_host_set_state(shost, SHOST_CANCEL_RECOVERY) == 0) {
74 shost->host_eh_scheduled++;
75 scsi_eh_wakeup(shost);
78 spin_unlock_irqrestore(shost->host_lock, flags);
80 EXPORT_SYMBOL_GPL(scsi_schedule_eh);
83 * scsi_eh_scmd_add - add scsi cmd to error handling.
84 * @scmd: scmd to run eh on.
85 * @eh_flag: optional SCSI_EH flag.
90 int scsi_eh_scmd_add(struct scsi_cmnd *scmd, int eh_flag)
92 struct Scsi_Host *shost = scmd->device->host;
99 spin_lock_irqsave(shost->host_lock, flags);
100 if (scsi_host_set_state(shost, SHOST_RECOVERY))
101 if (scsi_host_set_state(shost, SHOST_CANCEL_RECOVERY))
105 scmd->eh_eflags |= eh_flag;
106 list_add_tail(&scmd->eh_entry, &shost->eh_cmd_q);
107 shost->host_failed++;
108 scsi_eh_wakeup(shost);
110 spin_unlock_irqrestore(shost->host_lock, flags);
115 * scsi_add_timer - Start timeout timer for a single scsi command.
116 * @scmd: scsi command that is about to start running.
117 * @timeout: amount of time to allow this command to run.
118 * @complete: timeout function to call if timer isn't canceled.
121 * This should be turned into an inline function. Each scsi command
122 * has its own timer, and as it is added to the queue, we set up the
123 * timer. When the command completes, we cancel the timer.
125 void scsi_add_timer(struct scsi_cmnd *scmd, int timeout,
126 void (*complete)(struct scsi_cmnd *))
130 * If the clock was already running for this command, then
131 * first delete the timer. The timer handling code gets rather
132 * confused if we don't do this.
134 if (scmd->eh_timeout.function)
135 del_timer(&scmd->eh_timeout);
137 scmd->eh_timeout.data = (unsigned long)scmd;
138 scmd->eh_timeout.expires = jiffies + timeout;
139 scmd->eh_timeout.function = (void (*)(unsigned long)) complete;
141 SCSI_LOG_ERROR_RECOVERY(5, printk("%s: scmd: %p, time:"
142 " %d, (%p)\n", __FUNCTION__,
143 scmd, timeout, complete));
145 add_timer(&scmd->eh_timeout);
149 * scsi_delete_timer - Delete/cancel timer for a given function.
150 * @scmd: Cmd that we are canceling timer for
153 * This should be turned into an inline function.
156 * 1 if we were able to detach the timer. 0 if we blew it, and the
157 * timer function has already started to run.
159 int scsi_delete_timer(struct scsi_cmnd *scmd)
163 rtn = del_timer(&scmd->eh_timeout);
165 SCSI_LOG_ERROR_RECOVERY(5, printk("%s: scmd: %p,"
166 " rtn: %d\n", __FUNCTION__,
169 scmd->eh_timeout.data = (unsigned long)NULL;
170 scmd->eh_timeout.function = NULL;
176 * scsi_times_out - Timeout function for normal scsi commands.
177 * @scmd: Cmd that is timing out.
180 * We do not need to lock this. There is the potential for a race
181 * only in that the normal completion handling might run, but if the
182 * normal completion function determines that the timer has already
183 * fired, then it mustn't do anything.
185 void scsi_times_out(struct scsi_cmnd *scmd)
187 scsi_log_completion(scmd, TIMEOUT_ERROR);
189 if (scmd->device->host->transportt->eh_timed_out)
190 switch (scmd->device->host->transportt->eh_timed_out(scmd)) {
195 scsi_add_timer(scmd, scmd->timeout_per_command,
202 if (unlikely(!scsi_eh_scmd_add(scmd, SCSI_EH_CANCEL_CMD))) {
203 scmd->result |= DID_TIME_OUT << 16;
209 * scsi_block_when_processing_errors - Prevent cmds from being queued.
210 * @sdev: Device on which we are performing recovery.
213 * We block until the host is out of error recovery, and then check to
214 * see whether the host or the device is offline.
217 * 0 when dev was taken offline by error recovery. 1 OK to proceed.
219 int scsi_block_when_processing_errors(struct scsi_device *sdev)
223 wait_event(sdev->host->host_wait, !scsi_host_in_recovery(sdev->host));
225 online = scsi_device_online(sdev);
227 SCSI_LOG_ERROR_RECOVERY(5, printk("%s: rtn: %d\n", __FUNCTION__,
232 EXPORT_SYMBOL(scsi_block_when_processing_errors);
234 #ifdef CONFIG_SCSI_LOGGING
236 * scsi_eh_prt_fail_stats - Log info on failures.
237 * @shost: scsi host being recovered.
238 * @work_q: Queue of scsi cmds to process.
240 static inline void scsi_eh_prt_fail_stats(struct Scsi_Host *shost,
241 struct list_head *work_q)
243 struct scsi_cmnd *scmd;
244 struct scsi_device *sdev;
245 int total_failures = 0;
248 int devices_failed = 0;
250 shost_for_each_device(sdev, shost) {
251 list_for_each_entry(scmd, work_q, eh_entry) {
252 if (scmd->device == sdev) {
254 if (scmd->eh_eflags & SCSI_EH_CANCEL_CMD)
261 if (cmd_cancel || cmd_failed) {
262 SCSI_LOG_ERROR_RECOVERY(3,
263 sdev_printk(KERN_INFO, sdev,
264 "%s: cmds failed: %d, cancel: %d\n",
265 __FUNCTION__, cmd_failed,
273 SCSI_LOG_ERROR_RECOVERY(2, printk("Total of %d commands on %d"
274 " devices require eh work\n",
275 total_failures, devices_failed));
280 * scsi_check_sense - Examine scsi cmd sense
281 * @scmd: Cmd to have sense checked.
284 * SUCCESS or FAILED or NEEDS_RETRY
287 * When a deferred error is detected the current command has
288 * not been executed and needs retrying.
290 static int scsi_check_sense(struct scsi_cmnd *scmd)
292 struct scsi_sense_hdr sshdr;
294 if (! scsi_command_normalize_sense(scmd, &sshdr))
295 return FAILED; /* no valid sense data */
297 if (scsi_sense_is_deferred(&sshdr))
301 * Previous logic looked for FILEMARK, EOM or ILI which are
302 * mainly associated with tapes and returned SUCCESS.
304 if (sshdr.response_code == 0x70) {
306 if (scmd->sense_buffer[2] & 0xe0)
310 * descriptor format: look for "stream commands sense data
311 * descriptor" (see SSC-3). Assume single sense data
312 * descriptor. Ignore ILI from SBC-2 READ LONG and WRITE LONG.
314 if ((sshdr.additional_length > 3) &&
315 (scmd->sense_buffer[8] == 0x4) &&
316 (scmd->sense_buffer[11] & 0xe0))
320 switch (sshdr.sense_key) {
323 case RECOVERED_ERROR:
324 return /* soft_error */ SUCCESS;
326 case ABORTED_COMMAND:
331 * if we are expecting a cc/ua because of a bus reset that we
332 * performed, treat this just as a retry. otherwise this is
333 * information that we should pass up to the upper-level driver
334 * so that we can deal with it there.
336 if (scmd->device->expecting_cc_ua) {
337 scmd->device->expecting_cc_ua = 0;
341 * if the device is in the process of becoming ready, we
344 if ((sshdr.asc == 0x04) && (sshdr.ascq == 0x01))
347 * if the device is not started, we need to wake
348 * the error handler to start the motor
350 if (scmd->device->allow_restart &&
351 (sshdr.asc == 0x04) && (sshdr.ascq == 0x02))
355 /* these three are not supported */
357 case VOLUME_OVERFLOW:
365 if (scmd->device->retry_hwerror)
370 case ILLEGAL_REQUEST:
379 * scsi_eh_completed_normally - Disposition a eh cmd on return from LLD.
380 * @scmd: SCSI cmd to examine.
383 * This is *only* called when we are examining the status of commands
384 * queued during error recovery. the main difference here is that we
385 * don't allow for the possibility of retries here, and we are a lot
386 * more restrictive about what we consider acceptable.
388 static int scsi_eh_completed_normally(struct scsi_cmnd *scmd)
391 * first check the host byte, to see if there is anything in there
392 * that would indicate what we need to do.
394 if (host_byte(scmd->result) == DID_RESET) {
396 * rats. we are already in the error handler, so we now
397 * get to try and figure out what to do next. if the sense
398 * is valid, we have a pretty good idea of what to do.
399 * if not, we mark it as FAILED.
401 return scsi_check_sense(scmd);
403 if (host_byte(scmd->result) != DID_OK)
407 * next, check the message byte.
409 if (msg_byte(scmd->result) != COMMAND_COMPLETE)
413 * now, check the status byte to see if this indicates
416 switch (status_byte(scmd->result)) {
418 case COMMAND_TERMINATED:
420 case CHECK_CONDITION:
421 return scsi_check_sense(scmd);
423 case INTERMEDIATE_GOOD:
424 case INTERMEDIATE_C_GOOD:
426 * who knows? FIXME(eric)
431 case RESERVATION_CONFLICT:
439 * scsi_eh_done - Completion function for error handling.
440 * @scmd: Cmd that is done.
442 static void scsi_eh_done(struct scsi_cmnd *scmd)
444 struct completion *eh_action;
446 SCSI_LOG_ERROR_RECOVERY(3,
447 printk("%s scmd: %p result: %x\n",
448 __FUNCTION__, scmd, scmd->result));
450 eh_action = scmd->device->host->eh_action;
456 * scsi_send_eh_cmnd - submit a scsi command as part of error recory
457 * @scmd: SCSI command structure to hijack
459 * @cmnd_size: size in bytes of @cmnd
460 * @timeout: timeout for this request
461 * @copy_sense: request sense data if set to 1
463 * This function is used to send a scsi command down to a target device
464 * as part of the error recovery process. If @copy_sense is 0 the command
465 * sent must be one that does not transfer any data. If @copy_sense is 1
466 * the command must be REQUEST_SENSE and this functions copies out the
467 * sense buffer it got into @scmd->sense_buffer.
470 * SUCCESS or FAILED or NEEDS_RETRY
472 static int scsi_send_eh_cmnd(struct scsi_cmnd *scmd, unsigned char *cmnd,
473 int cmnd_size, int timeout, int copy_sense)
475 struct scsi_device *sdev = scmd->device;
476 struct Scsi_Host *shost = sdev->host;
477 int old_result = scmd->result;
478 DECLARE_COMPLETION_ONSTACK(done);
479 unsigned long timeleft;
481 struct scatterlist sgl;
482 unsigned char old_cmnd[MAX_COMMAND_SIZE];
483 enum dma_data_direction old_data_direction;
484 unsigned short old_use_sg;
485 unsigned char old_cmd_len;
486 unsigned old_bufflen;
491 * We need saved copies of a number of fields - this is because
492 * error handling may need to overwrite these with different values
493 * to run different commands, and once error handling is complete,
494 * we will need to restore these values prior to running the actual
497 old_buffer = scmd->request_buffer;
498 old_bufflen = scmd->request_bufflen;
499 memcpy(old_cmnd, scmd->cmnd, sizeof(scmd->cmnd));
500 old_data_direction = scmd->sc_data_direction;
501 old_cmd_len = scmd->cmd_len;
502 old_use_sg = scmd->use_sg;
504 memset(scmd->cmnd, 0, sizeof(scmd->cmnd));
505 memcpy(scmd->cmnd, cmnd, cmnd_size);
508 gfp_t gfp_mask = GFP_ATOMIC;
510 if (shost->hostt->unchecked_isa_dma)
511 gfp_mask |= __GFP_DMA;
513 sgl.page = alloc_page(gfp_mask);
519 scmd->sc_data_direction = DMA_FROM_DEVICE;
520 scmd->request_bufflen = sgl.length;
521 scmd->request_buffer = &sgl;
524 scmd->request_buffer = NULL;
525 scmd->request_bufflen = 0;
526 scmd->sc_data_direction = DMA_NONE;
531 scmd->cmd_len = COMMAND_SIZE(scmd->cmnd[0]);
533 if (sdev->scsi_level <= SCSI_2)
534 scmd->cmnd[1] = (scmd->cmnd[1] & 0x1f) |
535 (sdev->lun << 5 & 0xe0);
538 * Zero the sense buffer. The scsi spec mandates that any
539 * untransferred sense data should be interpreted as being zero.
541 memset(scmd->sense_buffer, 0, sizeof(scmd->sense_buffer));
543 shost->eh_action = &done;
545 spin_lock_irqsave(shost->host_lock, flags);
547 shost->hostt->queuecommand(scmd, scsi_eh_done);
548 spin_unlock_irqrestore(shost->host_lock, flags);
550 timeleft = wait_for_completion_timeout(&done, timeout);
552 shost->eh_action = NULL;
554 scsi_log_completion(scmd, SUCCESS);
556 SCSI_LOG_ERROR_RECOVERY(3,
557 printk("%s: scmd: %p, timeleft: %ld\n",
558 __FUNCTION__, scmd, timeleft));
561 * If there is time left scsi_eh_done got called, and we will
562 * examine the actual status codes to see whether the command
563 * actually did complete normally, else tell the host to forget
564 * about this command.
567 rtn = scsi_eh_completed_normally(scmd);
568 SCSI_LOG_ERROR_RECOVERY(3,
569 printk("%s: scsi_eh_completed_normally %x\n",
583 * FIXME(eric) - we are not tracking whether we could
584 * abort a timed out command or not. not sure how
585 * we should treat them differently anyways.
587 if (shost->hostt->eh_abort_handler)
588 shost->hostt->eh_abort_handler(scmd);
594 * Last chance to have valid sense data.
597 if (!SCSI_SENSE_VALID(scmd)) {
598 memcpy(scmd->sense_buffer, scmd->request_buffer,
599 sizeof(scmd->sense_buffer));
601 __free_page(sgl.page);
606 * Restore original data
608 scmd->request_buffer = old_buffer;
609 scmd->request_bufflen = old_bufflen;
610 memcpy(scmd->cmnd, old_cmnd, sizeof(scmd->cmnd));
611 scmd->sc_data_direction = old_data_direction;
612 scmd->cmd_len = old_cmd_len;
613 scmd->use_sg = old_use_sg;
614 scmd->result = old_result;
619 * scsi_request_sense - Request sense data from a particular target.
620 * @scmd: SCSI cmd for request sense.
623 * Some hosts automatically obtain this information, others require
624 * that we obtain it on our own. This function will *not* return until
625 * the command either times out, or it completes.
627 static int scsi_request_sense(struct scsi_cmnd *scmd)
629 static unsigned char generic_sense[6] =
630 {REQUEST_SENSE, 0, 0, 0, 252, 0};
632 return scsi_send_eh_cmnd(scmd, generic_sense, 6, SENSE_TIMEOUT, 1);
636 * scsi_eh_finish_cmd - Handle a cmd that eh is finished with.
637 * @scmd: Original SCSI cmd that eh has finished.
638 * @done_q: Queue for processed commands.
641 * We don't want to use the normal command completion while we are are
642 * still handling errors - it may cause other commands to be queued,
643 * and that would disturb what we are doing. thus we really want to
644 * keep a list of pending commands for final completion, and once we
645 * are ready to leave error handling we handle completion for real.
647 void scsi_eh_finish_cmd(struct scsi_cmnd *scmd, struct list_head *done_q)
649 scmd->device->host->host_failed--;
651 list_move_tail(&scmd->eh_entry, done_q);
653 EXPORT_SYMBOL(scsi_eh_finish_cmd);
656 * scsi_eh_get_sense - Get device sense data.
657 * @work_q: Queue of commands to process.
658 * @done_q: Queue of proccessed commands..
661 * See if we need to request sense information. if so, then get it
662 * now, so we have a better idea of what to do.
665 * This has the unfortunate side effect that if a shost adapter does
666 * not automatically request sense information, that we end up shutting
667 * it down before we request it.
669 * All drivers should request sense information internally these days,
670 * so for now all I have to say is tough noogies if you end up in here.
672 * XXX: Long term this code should go away, but that needs an audit of
675 int scsi_eh_get_sense(struct list_head *work_q,
676 struct list_head *done_q)
678 struct scsi_cmnd *scmd, *next;
681 list_for_each_entry_safe(scmd, next, work_q, eh_entry) {
682 if ((scmd->eh_eflags & SCSI_EH_CANCEL_CMD) ||
683 SCSI_SENSE_VALID(scmd))
686 SCSI_LOG_ERROR_RECOVERY(2, scmd_printk(KERN_INFO, scmd,
687 "%s: requesting sense\n",
689 rtn = scsi_request_sense(scmd);
693 SCSI_LOG_ERROR_RECOVERY(3, printk("sense requested for %p"
694 " result %x\n", scmd,
696 SCSI_LOG_ERROR_RECOVERY(3, scsi_print_sense("bh", scmd));
698 rtn = scsi_decide_disposition(scmd);
701 * if the result was normal, then just pass it along to the
705 /* we don't want this command reissued, just
706 * finished with the sense data, so set
707 * retries to the max allowed to ensure it
708 * won't get reissued */
709 scmd->retries = scmd->allowed;
710 else if (rtn != NEEDS_RETRY)
713 scsi_eh_finish_cmd(scmd, done_q);
716 return list_empty(work_q);
718 EXPORT_SYMBOL_GPL(scsi_eh_get_sense);
721 * scsi_try_to_abort_cmd - Ask host to abort a running command.
722 * @scmd: SCSI cmd to abort from Lower Level.
725 * This function will not return until the user's completion function
726 * has been called. there is no timeout on this operation. if the
727 * author of the low-level driver wishes this operation to be timed,
728 * they can provide this facility themselves. helper functions in
729 * scsi_error.c can be supplied to make this easier to do.
731 static int scsi_try_to_abort_cmd(struct scsi_cmnd *scmd)
733 if (!scmd->device->host->hostt->eh_abort_handler)
737 * scsi_done was called just after the command timed out and before
738 * we had a chance to process it. (db)
740 if (scmd->serial_number == 0)
742 return scmd->device->host->hostt->eh_abort_handler(scmd);
746 * scsi_eh_tur - Send TUR to device.
747 * @scmd: Scsi cmd to send TUR
750 * 0 - Device is ready. 1 - Device NOT ready.
752 static int scsi_eh_tur(struct scsi_cmnd *scmd)
754 static unsigned char tur_command[6] = {TEST_UNIT_READY, 0, 0, 0, 0, 0};
755 int retry_cnt = 1, rtn;
758 rtn = scsi_send_eh_cmnd(scmd, tur_command, 6, SENSE_TIMEOUT, 0);
760 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: scmd %p rtn %x\n",
761 __FUNCTION__, scmd, rtn));
776 * scsi_eh_abort_cmds - abort canceled commands.
777 * @shost: scsi host being recovered.
778 * @eh_done_q: list_head for processed commands.
781 * Try and see whether or not it makes sense to try and abort the
782 * running command. this only works out to be the case if we have one
783 * command that has timed out. if the command simply failed, it makes
784 * no sense to try and abort the command, since as far as the shost
785 * adapter is concerned, it isn't running.
787 static int scsi_eh_abort_cmds(struct list_head *work_q,
788 struct list_head *done_q)
790 struct scsi_cmnd *scmd, *next;
793 list_for_each_entry_safe(scmd, next, work_q, eh_entry) {
794 if (!(scmd->eh_eflags & SCSI_EH_CANCEL_CMD))
796 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: aborting cmd:"
797 "0x%p\n", current->comm,
799 rtn = scsi_try_to_abort_cmd(scmd);
800 if (rtn == SUCCESS) {
801 scmd->eh_eflags &= ~SCSI_EH_CANCEL_CMD;
802 if (!scsi_device_online(scmd->device) ||
803 !scsi_eh_tur(scmd)) {
804 scsi_eh_finish_cmd(scmd, done_q);
808 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: aborting"
815 return list_empty(work_q);
819 * scsi_try_bus_device_reset - Ask host to perform a BDR on a dev
820 * @scmd: SCSI cmd used to send BDR
823 * There is no timeout for this operation. if this operation is
824 * unreliable for a given host, then the host itself needs to put a
825 * timer on it, and set the host back to a consistent state prior to
828 static int scsi_try_bus_device_reset(struct scsi_cmnd *scmd)
832 if (!scmd->device->host->hostt->eh_device_reset_handler)
835 rtn = scmd->device->host->hostt->eh_device_reset_handler(scmd);
836 if (rtn == SUCCESS) {
837 scmd->device->was_reset = 1;
838 scmd->device->expecting_cc_ua = 1;
845 * scsi_eh_try_stu - Send START_UNIT to device.
846 * @scmd: Scsi cmd to send START_UNIT
849 * 0 - Device is ready. 1 - Device NOT ready.
851 static int scsi_eh_try_stu(struct scsi_cmnd *scmd)
853 static unsigned char stu_command[6] = {START_STOP, 0, 0, 0, 1, 0};
855 if (scmd->device->allow_restart) {
858 rtn = scsi_send_eh_cmnd(scmd, stu_command, 6,
859 START_UNIT_TIMEOUT, 0);
868 * scsi_eh_stu - send START_UNIT if needed
869 * @shost: scsi host being recovered.
870 * @eh_done_q: list_head for processed commands.
873 * If commands are failing due to not ready, initializing command required,
874 * try revalidating the device, which will end up sending a start unit.
876 static int scsi_eh_stu(struct Scsi_Host *shost,
877 struct list_head *work_q,
878 struct list_head *done_q)
880 struct scsi_cmnd *scmd, *stu_scmd, *next;
881 struct scsi_device *sdev;
883 shost_for_each_device(sdev, shost) {
885 list_for_each_entry(scmd, work_q, eh_entry)
886 if (scmd->device == sdev && SCSI_SENSE_VALID(scmd) &&
887 scsi_check_sense(scmd) == FAILED ) {
895 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending START_UNIT to sdev:"
896 " 0x%p\n", current->comm, sdev));
898 if (!scsi_eh_try_stu(stu_scmd)) {
899 if (!scsi_device_online(sdev) ||
900 !scsi_eh_tur(stu_scmd)) {
901 list_for_each_entry_safe(scmd, next,
903 if (scmd->device == sdev)
904 scsi_eh_finish_cmd(scmd, done_q);
908 SCSI_LOG_ERROR_RECOVERY(3,
909 printk("%s: START_UNIT failed to sdev:"
910 " 0x%p\n", current->comm, sdev));
914 return list_empty(work_q);
919 * scsi_eh_bus_device_reset - send bdr if needed
920 * @shost: scsi host being recovered.
921 * @eh_done_q: list_head for processed commands.
924 * Try a bus device reset. still, look to see whether we have multiple
925 * devices that are jammed or not - if we have multiple devices, it
926 * makes no sense to try bus_device_reset - we really would need to try
927 * a bus_reset instead.
929 static int scsi_eh_bus_device_reset(struct Scsi_Host *shost,
930 struct list_head *work_q,
931 struct list_head *done_q)
933 struct scsi_cmnd *scmd, *bdr_scmd, *next;
934 struct scsi_device *sdev;
937 shost_for_each_device(sdev, shost) {
939 list_for_each_entry(scmd, work_q, eh_entry)
940 if (scmd->device == sdev) {
948 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending BDR sdev:"
949 " 0x%p\n", current->comm,
951 rtn = scsi_try_bus_device_reset(bdr_scmd);
952 if (rtn == SUCCESS) {
953 if (!scsi_device_online(sdev) ||
954 !scsi_eh_tur(bdr_scmd)) {
955 list_for_each_entry_safe(scmd, next,
957 if (scmd->device == sdev)
958 scsi_eh_finish_cmd(scmd,
963 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: BDR"
971 return list_empty(work_q);
975 * scsi_try_bus_reset - ask host to perform a bus reset
976 * @scmd: SCSI cmd to send bus reset.
978 static int scsi_try_bus_reset(struct scsi_cmnd *scmd)
983 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Snd Bus RST\n",
986 if (!scmd->device->host->hostt->eh_bus_reset_handler)
989 rtn = scmd->device->host->hostt->eh_bus_reset_handler(scmd);
991 if (rtn == SUCCESS) {
992 if (!scmd->device->host->hostt->skip_settle_delay)
993 ssleep(BUS_RESET_SETTLE_TIME);
994 spin_lock_irqsave(scmd->device->host->host_lock, flags);
995 scsi_report_bus_reset(scmd->device->host,
997 spin_unlock_irqrestore(scmd->device->host->host_lock, flags);
1004 * scsi_try_host_reset - ask host adapter to reset itself
1005 * @scmd: SCSI cmd to send hsot reset.
1007 static int scsi_try_host_reset(struct scsi_cmnd *scmd)
1009 unsigned long flags;
1012 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Snd Host RST\n",
1015 if (!scmd->device->host->hostt->eh_host_reset_handler)
1018 rtn = scmd->device->host->hostt->eh_host_reset_handler(scmd);
1020 if (rtn == SUCCESS) {
1021 if (!scmd->device->host->hostt->skip_settle_delay)
1022 ssleep(HOST_RESET_SETTLE_TIME);
1023 spin_lock_irqsave(scmd->device->host->host_lock, flags);
1024 scsi_report_bus_reset(scmd->device->host,
1025 scmd_channel(scmd));
1026 spin_unlock_irqrestore(scmd->device->host->host_lock, flags);
1033 * scsi_eh_bus_reset - send a bus reset
1034 * @shost: scsi host being recovered.
1035 * @eh_done_q: list_head for processed commands.
1037 static int scsi_eh_bus_reset(struct Scsi_Host *shost,
1038 struct list_head *work_q,
1039 struct list_head *done_q)
1041 struct scsi_cmnd *scmd, *chan_scmd, *next;
1042 unsigned int channel;
1046 * we really want to loop over the various channels, and do this on
1047 * a channel by channel basis. we should also check to see if any
1048 * of the failed commands are on soft_reset devices, and if so, skip
1052 for (channel = 0; channel <= shost->max_channel; channel++) {
1054 list_for_each_entry(scmd, work_q, eh_entry) {
1055 if (channel == scmd_channel(scmd)) {
1059 * FIXME add back in some support for
1060 * soft_reset devices.
1067 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending BRST chan:"
1068 " %d\n", current->comm,
1070 rtn = scsi_try_bus_reset(chan_scmd);
1071 if (rtn == SUCCESS) {
1072 list_for_each_entry_safe(scmd, next, work_q, eh_entry) {
1073 if (channel == scmd_channel(scmd))
1074 if (!scsi_device_online(scmd->device) ||
1076 scsi_eh_finish_cmd(scmd,
1080 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: BRST"
1081 " failed chan: %d\n",
1086 return list_empty(work_q);
1090 * scsi_eh_host_reset - send a host reset
1091 * @work_q: list_head for processed commands.
1092 * @done_q: list_head for processed commands.
1094 static int scsi_eh_host_reset(struct list_head *work_q,
1095 struct list_head *done_q)
1097 struct scsi_cmnd *scmd, *next;
1100 if (!list_empty(work_q)) {
1101 scmd = list_entry(work_q->next,
1102 struct scsi_cmnd, eh_entry);
1104 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending HRST\n"
1107 rtn = scsi_try_host_reset(scmd);
1108 if (rtn == SUCCESS) {
1109 list_for_each_entry_safe(scmd, next, work_q, eh_entry) {
1110 if (!scsi_device_online(scmd->device) ||
1111 (!scsi_eh_try_stu(scmd) && !scsi_eh_tur(scmd)) ||
1113 scsi_eh_finish_cmd(scmd, done_q);
1116 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: HRST"
1121 return list_empty(work_q);
1125 * scsi_eh_offline_sdevs - offline scsi devices that fail to recover
1126 * @work_q: list_head for processed commands.
1127 * @done_q: list_head for processed commands.
1130 static void scsi_eh_offline_sdevs(struct list_head *work_q,
1131 struct list_head *done_q)
1133 struct scsi_cmnd *scmd, *next;
1135 list_for_each_entry_safe(scmd, next, work_q, eh_entry) {
1136 sdev_printk(KERN_INFO, scmd->device,
1137 "scsi: Device offlined - not"
1138 " ready after error recovery\n");
1139 scsi_device_set_state(scmd->device, SDEV_OFFLINE);
1140 if (scmd->eh_eflags & SCSI_EH_CANCEL_CMD) {
1142 * FIXME: Handle lost cmds.
1145 scsi_eh_finish_cmd(scmd, done_q);
1151 * scsi_decide_disposition - Disposition a cmd on return from LLD.
1152 * @scmd: SCSI cmd to examine.
1155 * This is *only* called when we are examining the status after sending
1156 * out the actual data command. any commands that are queued for error
1157 * recovery (e.g. test_unit_ready) do *not* come through here.
1159 * When this routine returns failed, it means the error handler thread
1160 * is woken. In cases where the error code indicates an error that
1161 * doesn't require the error handler read (i.e. we don't need to
1162 * abort/reset), this function should return SUCCESS.
1164 int scsi_decide_disposition(struct scsi_cmnd *scmd)
1169 * if the device is offline, then we clearly just pass the result back
1170 * up to the top level.
1172 if (!scsi_device_online(scmd->device)) {
1173 SCSI_LOG_ERROR_RECOVERY(5, printk("%s: device offline - report"
1180 * first check the host byte, to see if there is anything in there
1181 * that would indicate what we need to do.
1183 switch (host_byte(scmd->result)) {
1184 case DID_PASSTHROUGH:
1186 * no matter what, pass this through to the upper layer.
1187 * nuke this special code so that it looks like we are saying
1190 scmd->result &= 0xff00ffff;
1194 * looks good. drop through, and check the next byte.
1197 case DID_NO_CONNECT:
1198 case DID_BAD_TARGET:
1201 * note - this means that we just report the status back
1202 * to the top level driver, not that we actually think
1203 * that it indicates SUCCESS.
1207 * when the low level driver returns did_soft_error,
1208 * it is responsible for keeping an internal retry counter
1209 * in order to avoid endless loops (db)
1211 * actually this is a bug in this function here. we should
1212 * be mindful of the maximum number of retries specified
1213 * and not get stuck in a loop.
1215 case DID_SOFT_ERROR:
1221 return ADD_TO_MLQUEUE;
1224 if (msg_byte(scmd->result) == COMMAND_COMPLETE &&
1225 status_byte(scmd->result) == RESERVATION_CONFLICT)
1227 * execute reservation conflict processing code
1238 * when we scan the bus, we get timeout messages for
1239 * these commands if there is no device available.
1240 * other hosts report did_no_connect for the same thing.
1242 if ((scmd->cmnd[0] == TEST_UNIT_READY ||
1243 scmd->cmnd[0] == INQUIRY)) {
1255 * next, check the message byte.
1257 if (msg_byte(scmd->result) != COMMAND_COMPLETE)
1261 * check the status byte to see if this indicates anything special.
1263 switch (status_byte(scmd->result)) {
1266 * the case of trying to send too many commands to a
1267 * tagged queueing device.
1271 * device can't talk to us at the moment. Should only
1272 * occur (SAM-3) when the task queue is empty, so will cause
1273 * the empty queue handling to trigger a stall in the
1276 return ADD_TO_MLQUEUE;
1278 case COMMAND_TERMINATED:
1281 case CHECK_CONDITION:
1282 rtn = scsi_check_sense(scmd);
1283 if (rtn == NEEDS_RETRY)
1285 /* if rtn == FAILED, we have no sense information;
1286 * returning FAILED will wake the error handler thread
1287 * to collect the sense and redo the decide
1290 case CONDITION_GOOD:
1291 case INTERMEDIATE_GOOD:
1292 case INTERMEDIATE_C_GOOD:
1295 * who knows? FIXME(eric)
1299 case RESERVATION_CONFLICT:
1300 sdev_printk(KERN_INFO, scmd->device,
1301 "reservation conflict\n");
1302 return SUCCESS; /* causes immediate i/o error */
1310 /* we requeue for retry because the error was retryable, and
1311 * the request was not marked fast fail. Note that above,
1312 * even if the request is marked fast fail, we still requeue
1313 * for queue congestion conditions (QUEUE_FULL or BUSY) */
1314 if ((++scmd->retries) <= scmd->allowed
1315 && !blk_noretry_request(scmd->request)) {
1319 * no more retries - report this one back to upper level.
1326 * scsi_eh_lock_door - Prevent medium removal for the specified device
1327 * @sdev: SCSI device to prevent medium removal
1330 * We must be called from process context; scsi_allocate_request()
1334 * We queue up an asynchronous "ALLOW MEDIUM REMOVAL" request on the
1335 * head of the devices request queue, and continue.
1338 * scsi_allocate_request() may sleep waiting for existing requests to
1339 * be processed. However, since we haven't kicked off any request
1340 * processing for this host, this may deadlock.
1342 * If scsi_allocate_request() fails for what ever reason, we
1343 * completely forget to lock the door.
1345 static void scsi_eh_lock_door(struct scsi_device *sdev)
1347 unsigned char cmnd[MAX_COMMAND_SIZE];
1349 cmnd[0] = ALLOW_MEDIUM_REMOVAL;
1353 cmnd[4] = SCSI_REMOVAL_PREVENT;
1356 scsi_execute_async(sdev, cmnd, 6, DMA_NONE, NULL, 0, 0, 10 * HZ,
1357 5, NULL, NULL, GFP_KERNEL);
1362 * scsi_restart_operations - restart io operations to the specified host.
1363 * @shost: Host we are restarting.
1366 * When we entered the error handler, we blocked all further i/o to
1367 * this device. we need to 'reverse' this process.
1369 static void scsi_restart_operations(struct Scsi_Host *shost)
1371 struct scsi_device *sdev;
1372 unsigned long flags;
1375 * If the door was locked, we need to insert a door lock request
1376 * onto the head of the SCSI request queue for the device. There
1377 * is no point trying to lock the door of an off-line device.
1379 shost_for_each_device(sdev, shost) {
1380 if (scsi_device_online(sdev) && sdev->locked)
1381 scsi_eh_lock_door(sdev);
1385 * next free up anything directly waiting upon the host. this
1386 * will be requests for character device operations, and also for
1387 * ioctls to queued block devices.
1389 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: waking up host to restart\n",
1392 spin_lock_irqsave(shost->host_lock, flags);
1393 if (scsi_host_set_state(shost, SHOST_RUNNING))
1394 if (scsi_host_set_state(shost, SHOST_CANCEL))
1395 BUG_ON(scsi_host_set_state(shost, SHOST_DEL));
1396 spin_unlock_irqrestore(shost->host_lock, flags);
1398 wake_up(&shost->host_wait);
1401 * finally we need to re-initiate requests that may be pending. we will
1402 * have had everything blocked while error handling is taking place, and
1403 * now that error recovery is done, we will need to ensure that these
1404 * requests are started.
1406 scsi_run_host_queues(shost);
1410 * scsi_eh_ready_devs - check device ready state and recover if not.
1411 * @shost: host to be recovered.
1412 * @eh_done_q: list_head for processed commands.
1415 void scsi_eh_ready_devs(struct Scsi_Host *shost,
1416 struct list_head *work_q,
1417 struct list_head *done_q)
1419 if (!scsi_eh_stu(shost, work_q, done_q))
1420 if (!scsi_eh_bus_device_reset(shost, work_q, done_q))
1421 if (!scsi_eh_bus_reset(shost, work_q, done_q))
1422 if (!scsi_eh_host_reset(work_q, done_q))
1423 scsi_eh_offline_sdevs(work_q, done_q);
1425 EXPORT_SYMBOL_GPL(scsi_eh_ready_devs);
1428 * scsi_eh_flush_done_q - finish processed commands or retry them.
1429 * @done_q: list_head of processed commands.
1432 void scsi_eh_flush_done_q(struct list_head *done_q)
1434 struct scsi_cmnd *scmd, *next;
1436 list_for_each_entry_safe(scmd, next, done_q, eh_entry) {
1437 list_del_init(&scmd->eh_entry);
1438 if (scsi_device_online(scmd->device) &&
1439 !blk_noretry_request(scmd->request) &&
1440 (++scmd->retries <= scmd->allowed)) {
1441 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: flush"
1445 scsi_queue_insert(scmd, SCSI_MLQUEUE_EH_RETRY);
1448 * If just we got sense for the device (called
1449 * scsi_eh_get_sense), scmd->result is already
1450 * set, do not set DRIVER_TIMEOUT.
1453 scmd->result |= (DRIVER_TIMEOUT << 24);
1454 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: flush finish"
1456 current->comm, scmd));
1457 scsi_finish_command(scmd);
1461 EXPORT_SYMBOL(scsi_eh_flush_done_q);
1464 * scsi_unjam_host - Attempt to fix a host which has a cmd that failed.
1465 * @shost: Host to unjam.
1468 * When we come in here, we *know* that all commands on the bus have
1469 * either completed, failed or timed out. we also know that no further
1470 * commands are being sent to the host, so things are relatively quiet
1471 * and we have freedom to fiddle with things as we wish.
1473 * This is only the *default* implementation. it is possible for
1474 * individual drivers to supply their own version of this function, and
1475 * if the maintainer wishes to do this, it is strongly suggested that
1476 * this function be taken as a template and modified. this function
1477 * was designed to correctly handle problems for about 95% of the
1478 * different cases out there, and it should always provide at least a
1479 * reasonable amount of error recovery.
1481 * Any command marked 'failed' or 'timeout' must eventually have
1482 * scsi_finish_cmd() called for it. we do all of the retry stuff
1483 * here, so when we restart the host after we return it should have an
1486 static void scsi_unjam_host(struct Scsi_Host *shost)
1488 unsigned long flags;
1489 LIST_HEAD(eh_work_q);
1490 LIST_HEAD(eh_done_q);
1492 spin_lock_irqsave(shost->host_lock, flags);
1493 list_splice_init(&shost->eh_cmd_q, &eh_work_q);
1494 spin_unlock_irqrestore(shost->host_lock, flags);
1496 SCSI_LOG_ERROR_RECOVERY(1, scsi_eh_prt_fail_stats(shost, &eh_work_q));
1498 if (!scsi_eh_get_sense(&eh_work_q, &eh_done_q))
1499 if (!scsi_eh_abort_cmds(&eh_work_q, &eh_done_q))
1500 scsi_eh_ready_devs(shost, &eh_work_q, &eh_done_q);
1502 scsi_eh_flush_done_q(&eh_done_q);
1506 * scsi_error_handler - SCSI error handler thread
1507 * @data: Host for which we are running.
1510 * This is the main error handling loop. This is run as a kernel thread
1511 * for every SCSI host and handles all error handling activity.
1513 int scsi_error_handler(void *data)
1515 struct Scsi_Host *shost = data;
1517 current->flags |= PF_NOFREEZE;
1520 * We use TASK_INTERRUPTIBLE so that the thread is not
1521 * counted against the load average as a running process.
1522 * We never actually get interrupted because kthread_run
1523 * disables singal delivery for the created thread.
1525 set_current_state(TASK_INTERRUPTIBLE);
1526 while (!kthread_should_stop()) {
1527 if ((shost->host_failed == 0 && shost->host_eh_scheduled == 0) ||
1528 shost->host_failed != shost->host_busy) {
1529 SCSI_LOG_ERROR_RECOVERY(1,
1530 printk("Error handler scsi_eh_%d sleeping\n",
1533 set_current_state(TASK_INTERRUPTIBLE);
1537 __set_current_state(TASK_RUNNING);
1538 SCSI_LOG_ERROR_RECOVERY(1,
1539 printk("Error handler scsi_eh_%d waking up\n",
1543 * We have a host that is failing for some reason. Figure out
1544 * what we need to do to get it up and online again (if we can).
1545 * If we fail, we end up taking the thing offline.
1547 if (shost->transportt->eh_strategy_handler)
1548 shost->transportt->eh_strategy_handler(shost);
1550 scsi_unjam_host(shost);
1553 * Note - if the above fails completely, the action is to take
1554 * individual devices offline and flush the queue of any
1555 * outstanding requests that may have been pending. When we
1556 * restart, we restart any I/O to any other devices on the bus
1557 * which are still online.
1559 scsi_restart_operations(shost);
1560 set_current_state(TASK_INTERRUPTIBLE);
1562 __set_current_state(TASK_RUNNING);
1564 SCSI_LOG_ERROR_RECOVERY(1,
1565 printk("Error handler scsi_eh_%d exiting\n", shost->host_no));
1566 shost->ehandler = NULL;
1571 * Function: scsi_report_bus_reset()
1573 * Purpose: Utility function used by low-level drivers to report that
1574 * they have observed a bus reset on the bus being handled.
1576 * Arguments: shost - Host in question
1577 * channel - channel on which reset was observed.
1581 * Lock status: Host lock must be held.
1583 * Notes: This only needs to be called if the reset is one which
1584 * originates from an unknown location. Resets originated
1585 * by the mid-level itself don't need to call this, but there
1586 * should be no harm.
1588 * The main purpose of this is to make sure that a CHECK_CONDITION
1589 * is properly treated.
1591 void scsi_report_bus_reset(struct Scsi_Host *shost, int channel)
1593 struct scsi_device *sdev;
1595 __shost_for_each_device(sdev, shost) {
1596 if (channel == sdev_channel(sdev)) {
1597 sdev->was_reset = 1;
1598 sdev->expecting_cc_ua = 1;
1602 EXPORT_SYMBOL(scsi_report_bus_reset);
1605 * Function: scsi_report_device_reset()
1607 * Purpose: Utility function used by low-level drivers to report that
1608 * they have observed a device reset on the device being handled.
1610 * Arguments: shost - Host in question
1611 * channel - channel on which reset was observed
1612 * target - target on which reset was observed
1616 * Lock status: Host lock must be held
1618 * Notes: This only needs to be called if the reset is one which
1619 * originates from an unknown location. Resets originated
1620 * by the mid-level itself don't need to call this, but there
1621 * should be no harm.
1623 * The main purpose of this is to make sure that a CHECK_CONDITION
1624 * is properly treated.
1626 void scsi_report_device_reset(struct Scsi_Host *shost, int channel, int target)
1628 struct scsi_device *sdev;
1630 __shost_for_each_device(sdev, shost) {
1631 if (channel == sdev_channel(sdev) &&
1632 target == sdev_id(sdev)) {
1633 sdev->was_reset = 1;
1634 sdev->expecting_cc_ua = 1;
1638 EXPORT_SYMBOL(scsi_report_device_reset);
1641 scsi_reset_provider_done_command(struct scsi_cmnd *scmd)
1646 * Function: scsi_reset_provider
1648 * Purpose: Send requested reset to a bus or device at any phase.
1650 * Arguments: device - device to send reset to
1651 * flag - reset type (see scsi.h)
1653 * Returns: SUCCESS/FAILURE.
1655 * Notes: This is used by the SCSI Generic driver to provide
1656 * Bus/Device reset capability.
1659 scsi_reset_provider(struct scsi_device *dev, int flag)
1661 struct scsi_cmnd *scmd = scsi_get_command(dev, GFP_KERNEL);
1662 struct Scsi_Host *shost = dev->host;
1664 unsigned long flags;
1667 scmd->request = &req;
1668 memset(&scmd->eh_timeout, 0, sizeof(scmd->eh_timeout));
1670 memset(&scmd->cmnd, '\0', sizeof(scmd->cmnd));
1672 scmd->scsi_done = scsi_reset_provider_done_command;
1674 scmd->request_buffer = NULL;
1675 scmd->request_bufflen = 0;
1679 scmd->sc_data_direction = DMA_BIDIRECTIONAL;
1681 init_timer(&scmd->eh_timeout);
1684 * Sometimes the command can get back into the timer chain,
1685 * so use the pid as an identifier.
1689 spin_lock_irqsave(shost->host_lock, flags);
1690 shost->tmf_in_progress = 1;
1691 spin_unlock_irqrestore(shost->host_lock, flags);
1694 case SCSI_TRY_RESET_DEVICE:
1695 rtn = scsi_try_bus_device_reset(scmd);
1699 case SCSI_TRY_RESET_BUS:
1700 rtn = scsi_try_bus_reset(scmd);
1704 case SCSI_TRY_RESET_HOST:
1705 rtn = scsi_try_host_reset(scmd);
1711 spin_lock_irqsave(shost->host_lock, flags);
1712 shost->tmf_in_progress = 0;
1713 spin_unlock_irqrestore(shost->host_lock, flags);
1716 * be sure to wake up anyone who was sleeping or had their queue
1717 * suspended while we performed the TMF.
1719 SCSI_LOG_ERROR_RECOVERY(3,
1720 printk("%s: waking up host to restart after TMF\n",
1723 wake_up(&shost->host_wait);
1725 scsi_run_host_queues(shost);
1727 scsi_next_command(scmd);
1730 EXPORT_SYMBOL(scsi_reset_provider);
1733 * scsi_normalize_sense - normalize main elements from either fixed or
1734 * descriptor sense data format into a common format.
1736 * @sense_buffer: byte array containing sense data returned by device
1737 * @sb_len: number of valid bytes in sense_buffer
1738 * @sshdr: pointer to instance of structure that common
1739 * elements are written to.
1742 * The "main elements" from sense data are: response_code, sense_key,
1743 * asc, ascq and additional_length (only for descriptor format).
1745 * Typically this function can be called after a device has
1746 * responded to a SCSI command with the CHECK_CONDITION status.
1749 * 1 if valid sense data information found, else 0;
1751 int scsi_normalize_sense(const u8 *sense_buffer, int sb_len,
1752 struct scsi_sense_hdr *sshdr)
1754 if (!sense_buffer || !sb_len)
1757 memset(sshdr, 0, sizeof(struct scsi_sense_hdr));
1759 sshdr->response_code = (sense_buffer[0] & 0x7f);
1761 if (!scsi_sense_valid(sshdr))
1764 if (sshdr->response_code >= 0x72) {
1769 sshdr->sense_key = (sense_buffer[1] & 0xf);
1771 sshdr->asc = sense_buffer[2];
1773 sshdr->ascq = sense_buffer[3];
1775 sshdr->additional_length = sense_buffer[7];
1781 sshdr->sense_key = (sense_buffer[2] & 0xf);
1783 sb_len = (sb_len < (sense_buffer[7] + 8)) ?
1784 sb_len : (sense_buffer[7] + 8);
1786 sshdr->asc = sense_buffer[12];
1788 sshdr->ascq = sense_buffer[13];
1794 EXPORT_SYMBOL(scsi_normalize_sense);
1796 int scsi_command_normalize_sense(struct scsi_cmnd *cmd,
1797 struct scsi_sense_hdr *sshdr)
1799 return scsi_normalize_sense(cmd->sense_buffer,
1800 sizeof(cmd->sense_buffer), sshdr);
1802 EXPORT_SYMBOL(scsi_command_normalize_sense);
1805 * scsi_sense_desc_find - search for a given descriptor type in
1806 * descriptor sense data format.
1808 * @sense_buffer: byte array of descriptor format sense data
1809 * @sb_len: number of valid bytes in sense_buffer
1810 * @desc_type: value of descriptor type to find
1811 * (e.g. 0 -> information)
1814 * only valid when sense data is in descriptor format
1817 * pointer to start of (first) descriptor if found else NULL
1819 const u8 * scsi_sense_desc_find(const u8 * sense_buffer, int sb_len,
1822 int add_sen_len, add_len, desc_len, k;
1825 if ((sb_len < 8) || (0 == (add_sen_len = sense_buffer[7])))
1827 if ((sense_buffer[0] < 0x72) || (sense_buffer[0] > 0x73))
1829 add_sen_len = (add_sen_len < (sb_len - 8)) ?
1830 add_sen_len : (sb_len - 8);
1831 descp = &sense_buffer[8];
1832 for (desc_len = 0, k = 0; k < add_sen_len; k += desc_len) {
1834 add_len = (k < (add_sen_len - 1)) ? descp[1]: -1;
1835 desc_len = add_len + 2;
1836 if (descp[0] == desc_type)
1838 if (add_len < 0) // short descriptor ??
1843 EXPORT_SYMBOL(scsi_sense_desc_find);
1846 * scsi_get_sense_info_fld - attempts to get information field from
1847 * sense data (either fixed or descriptor format)
1849 * @sense_buffer: byte array of sense data
1850 * @sb_len: number of valid bytes in sense_buffer
1851 * @info_out: pointer to 64 integer where 8 or 4 byte information
1852 * field will be placed if found.
1855 * 1 if information field found, 0 if not found.
1857 int scsi_get_sense_info_fld(const u8 * sense_buffer, int sb_len,
1866 switch (sense_buffer[0] & 0x7f) {
1869 if (sense_buffer[0] & 0x80) {
1870 *info_out = (sense_buffer[3] << 24) +
1871 (sense_buffer[4] << 16) +
1872 (sense_buffer[5] << 8) + sense_buffer[6];
1878 ucp = scsi_sense_desc_find(sense_buffer, sb_len,
1880 if (ucp && (0xa == ucp[1])) {
1882 for (j = 0; j < 8; ++j) {
1895 EXPORT_SYMBOL(scsi_get_sense_info_fld);