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/kernel.h>
22 #include <linux/freezer.h>
23 #include <linux/kthread.h>
24 #include <linux/interrupt.h>
25 #include <linux/blkdev.h>
26 #include <linux/delay.h>
27 #include <linux/scatterlist.h>
29 #include <scsi/scsi.h>
30 #include <scsi/scsi_cmnd.h>
31 #include <scsi/scsi_dbg.h>
32 #include <scsi/scsi_device.h>
33 #include <scsi/scsi_eh.h>
34 #include <scsi/scsi_transport.h>
35 #include <scsi/scsi_host.h>
36 #include <scsi/scsi_ioctl.h>
38 #include "scsi_priv.h"
39 #include "scsi_logging.h"
40 #include "scsi_transport_api.h"
42 #define SENSE_TIMEOUT (10*HZ)
45 * These should *probably* be handled by the host itself.
46 * Since it is allowed to sleep, it probably should.
48 #define BUS_RESET_SETTLE_TIME (10)
49 #define HOST_RESET_SETTLE_TIME (10)
51 /* called with shost->host_lock held */
52 void scsi_eh_wakeup(struct Scsi_Host
*shost
)
54 if (shost
->host_busy
== shost
->host_failed
) {
55 wake_up_process(shost
->ehandler
);
56 SCSI_LOG_ERROR_RECOVERY(5,
57 printk("Waking error handler thread\n"));
62 * scsi_schedule_eh - schedule EH for SCSI host
63 * @shost: SCSI host to invoke error handling on.
65 * Schedule SCSI EH without scmd.
67 void scsi_schedule_eh(struct Scsi_Host
*shost
)
71 spin_lock_irqsave(shost
->host_lock
, flags
);
73 if (scsi_host_set_state(shost
, SHOST_RECOVERY
) == 0 ||
74 scsi_host_set_state(shost
, SHOST_CANCEL_RECOVERY
) == 0) {
75 shost
->host_eh_scheduled
++;
76 scsi_eh_wakeup(shost
);
79 spin_unlock_irqrestore(shost
->host_lock
, flags
);
81 EXPORT_SYMBOL_GPL(scsi_schedule_eh
);
84 * scsi_eh_scmd_add - add scsi cmd to error handling.
85 * @scmd: scmd to run eh on.
86 * @eh_flag: optional SCSI_EH flag.
91 int scsi_eh_scmd_add(struct scsi_cmnd
*scmd
, int eh_flag
)
93 struct Scsi_Host
*shost
= scmd
->device
->host
;
100 spin_lock_irqsave(shost
->host_lock
, flags
);
101 if (scsi_host_set_state(shost
, SHOST_RECOVERY
))
102 if (scsi_host_set_state(shost
, SHOST_CANCEL_RECOVERY
))
106 scmd
->eh_eflags
|= eh_flag
;
107 list_add_tail(&scmd
->eh_entry
, &shost
->eh_cmd_q
);
108 shost
->host_failed
++;
109 scsi_eh_wakeup(shost
);
111 spin_unlock_irqrestore(shost
->host_lock
, flags
);
116 * scsi_add_timer - Start timeout timer for a single scsi command.
117 * @scmd: scsi command that is about to start running.
118 * @timeout: amount of time to allow this command to run.
119 * @complete: timeout function to call if timer isn't canceled.
122 * This should be turned into an inline function. Each scsi command
123 * has its own timer, and as it is added to the queue, we set up the
124 * timer. When the command completes, we cancel the timer.
126 void scsi_add_timer(struct scsi_cmnd
*scmd
, int timeout
,
127 void (*complete
)(struct scsi_cmnd
*))
131 * If the clock was already running for this command, then
132 * first delete the timer. The timer handling code gets rather
133 * confused if we don't do this.
135 if (scmd
->eh_timeout
.function
)
136 del_timer(&scmd
->eh_timeout
);
138 scmd
->eh_timeout
.data
= (unsigned long)scmd
;
139 scmd
->eh_timeout
.expires
= jiffies
+ timeout
;
140 scmd
->eh_timeout
.function
= (void (*)(unsigned long)) complete
;
142 SCSI_LOG_ERROR_RECOVERY(5, printk("%s: scmd: %p, time:"
143 " %d, (%p)\n", __FUNCTION__
,
144 scmd
, timeout
, complete
));
146 add_timer(&scmd
->eh_timeout
);
150 * scsi_delete_timer - Delete/cancel timer for a given function.
151 * @scmd: Cmd that we are canceling timer for
154 * This should be turned into an inline function.
157 * 1 if we were able to detach the timer. 0 if we blew it, and the
158 * timer function has already started to run.
160 int scsi_delete_timer(struct scsi_cmnd
*scmd
)
164 rtn
= del_timer(&scmd
->eh_timeout
);
166 SCSI_LOG_ERROR_RECOVERY(5, printk("%s: scmd: %p,"
167 " rtn: %d\n", __FUNCTION__
,
170 scmd
->eh_timeout
.data
= (unsigned long)NULL
;
171 scmd
->eh_timeout
.function
= NULL
;
177 * scsi_times_out - Timeout function for normal scsi commands.
178 * @scmd: Cmd that is timing out.
181 * We do not need to lock this. There is the potential for a race
182 * only in that the normal completion handling might run, but if the
183 * normal completion function determines that the timer has already
184 * fired, then it mustn't do anything.
186 void scsi_times_out(struct scsi_cmnd
*scmd
)
188 enum scsi_eh_timer_return (* eh_timed_out
)(struct scsi_cmnd
*);
190 scsi_log_completion(scmd
, TIMEOUT_ERROR
);
192 if (scmd
->device
->host
->transportt
->eh_timed_out
)
193 eh_timed_out
= scmd
->device
->host
->transportt
->eh_timed_out
;
194 else if (scmd
->device
->host
->hostt
->eh_timed_out
)
195 eh_timed_out
= scmd
->device
->host
->hostt
->eh_timed_out
;
200 switch (eh_timed_out(scmd
)) {
205 scsi_add_timer(scmd
, scmd
->timeout_per_command
,
212 if (unlikely(!scsi_eh_scmd_add(scmd
, SCSI_EH_CANCEL_CMD
))) {
213 scmd
->result
|= DID_TIME_OUT
<< 16;
219 * scsi_block_when_processing_errors - Prevent cmds from being queued.
220 * @sdev: Device on which we are performing recovery.
223 * We block until the host is out of error recovery, and then check to
224 * see whether the host or the device is offline.
227 * 0 when dev was taken offline by error recovery. 1 OK to proceed.
229 int scsi_block_when_processing_errors(struct scsi_device
*sdev
)
233 wait_event(sdev
->host
->host_wait
, !scsi_host_in_recovery(sdev
->host
));
235 online
= scsi_device_online(sdev
);
237 SCSI_LOG_ERROR_RECOVERY(5, printk("%s: rtn: %d\n", __FUNCTION__
,
242 EXPORT_SYMBOL(scsi_block_when_processing_errors
);
244 #ifdef CONFIG_SCSI_LOGGING
246 * scsi_eh_prt_fail_stats - Log info on failures.
247 * @shost: scsi host being recovered.
248 * @work_q: Queue of scsi cmds to process.
250 static inline void scsi_eh_prt_fail_stats(struct Scsi_Host
*shost
,
251 struct list_head
*work_q
)
253 struct scsi_cmnd
*scmd
;
254 struct scsi_device
*sdev
;
255 int total_failures
= 0;
258 int devices_failed
= 0;
260 shost_for_each_device(sdev
, shost
) {
261 list_for_each_entry(scmd
, work_q
, eh_entry
) {
262 if (scmd
->device
== sdev
) {
264 if (scmd
->eh_eflags
& SCSI_EH_CANCEL_CMD
)
271 if (cmd_cancel
|| cmd_failed
) {
272 SCSI_LOG_ERROR_RECOVERY(3,
273 sdev_printk(KERN_INFO
, sdev
,
274 "%s: cmds failed: %d, cancel: %d\n",
275 __FUNCTION__
, cmd_failed
,
283 SCSI_LOG_ERROR_RECOVERY(2, printk("Total of %d commands on %d"
284 " devices require eh work\n",
285 total_failures
, devices_failed
));
290 * scsi_check_sense - Examine scsi cmd sense
291 * @scmd: Cmd to have sense checked.
294 * SUCCESS or FAILED or NEEDS_RETRY
297 * When a deferred error is detected the current command has
298 * not been executed and needs retrying.
300 static int scsi_check_sense(struct scsi_cmnd
*scmd
)
302 struct scsi_sense_hdr sshdr
;
304 if (! scsi_command_normalize_sense(scmd
, &sshdr
))
305 return FAILED
; /* no valid sense data */
307 if (scsi_sense_is_deferred(&sshdr
))
311 * Previous logic looked for FILEMARK, EOM or ILI which are
312 * mainly associated with tapes and returned SUCCESS.
314 if (sshdr
.response_code
== 0x70) {
316 if (scmd
->sense_buffer
[2] & 0xe0)
320 * descriptor format: look for "stream commands sense data
321 * descriptor" (see SSC-3). Assume single sense data
322 * descriptor. Ignore ILI from SBC-2 READ LONG and WRITE LONG.
324 if ((sshdr
.additional_length
> 3) &&
325 (scmd
->sense_buffer
[8] == 0x4) &&
326 (scmd
->sense_buffer
[11] & 0xe0))
330 switch (sshdr
.sense_key
) {
333 case RECOVERED_ERROR
:
334 return /* soft_error */ SUCCESS
;
336 case ABORTED_COMMAND
:
341 * if we are expecting a cc/ua because of a bus reset that we
342 * performed, treat this just as a retry. otherwise this is
343 * information that we should pass up to the upper-level driver
344 * so that we can deal with it there.
346 if (scmd
->device
->expecting_cc_ua
) {
347 scmd
->device
->expecting_cc_ua
= 0;
351 * if the device is in the process of becoming ready, we
354 if ((sshdr
.asc
== 0x04) && (sshdr
.ascq
== 0x01))
357 * if the device is not started, we need to wake
358 * the error handler to start the motor
360 if (scmd
->device
->allow_restart
&&
361 (sshdr
.asc
== 0x04) && (sshdr
.ascq
== 0x02))
365 /* these three are not supported */
367 case VOLUME_OVERFLOW
:
372 if (sshdr
.asc
== 0x11 || /* UNRECOVERED READ ERR */
373 sshdr
.asc
== 0x13 || /* AMNF DATA FIELD */
374 sshdr
.asc
== 0x14) { /* RECORD NOT FOUND */
380 if (scmd
->device
->retry_hwerror
)
385 case ILLEGAL_REQUEST
:
394 * scsi_eh_completed_normally - Disposition a eh cmd on return from LLD.
395 * @scmd: SCSI cmd to examine.
398 * This is *only* called when we are examining the status of commands
399 * queued during error recovery. the main difference here is that we
400 * don't allow for the possibility of retries here, and we are a lot
401 * more restrictive about what we consider acceptable.
403 static int scsi_eh_completed_normally(struct scsi_cmnd
*scmd
)
406 * first check the host byte, to see if there is anything in there
407 * that would indicate what we need to do.
409 if (host_byte(scmd
->result
) == DID_RESET
) {
411 * rats. we are already in the error handler, so we now
412 * get to try and figure out what to do next. if the sense
413 * is valid, we have a pretty good idea of what to do.
414 * if not, we mark it as FAILED.
416 return scsi_check_sense(scmd
);
418 if (host_byte(scmd
->result
) != DID_OK
)
422 * next, check the message byte.
424 if (msg_byte(scmd
->result
) != COMMAND_COMPLETE
)
428 * now, check the status byte to see if this indicates
431 switch (status_byte(scmd
->result
)) {
433 case COMMAND_TERMINATED
:
435 case CHECK_CONDITION
:
436 return scsi_check_sense(scmd
);
438 case INTERMEDIATE_GOOD
:
439 case INTERMEDIATE_C_GOOD
:
441 * who knows? FIXME(eric)
446 case RESERVATION_CONFLICT
:
454 * scsi_eh_done - Completion function for error handling.
455 * @scmd: Cmd that is done.
457 static void scsi_eh_done(struct scsi_cmnd
*scmd
)
459 struct completion
*eh_action
;
461 SCSI_LOG_ERROR_RECOVERY(3,
462 printk("%s scmd: %p result: %x\n",
463 __FUNCTION__
, scmd
, scmd
->result
));
465 eh_action
= scmd
->device
->host
->eh_action
;
471 * scsi_try_host_reset - ask host adapter to reset itself
472 * @scmd: SCSI cmd to send hsot reset.
474 static int scsi_try_host_reset(struct scsi_cmnd
*scmd
)
479 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Snd Host RST\n",
482 if (!scmd
->device
->host
->hostt
->eh_host_reset_handler
)
485 rtn
= scmd
->device
->host
->hostt
->eh_host_reset_handler(scmd
);
487 if (rtn
== SUCCESS
) {
488 if (!scmd
->device
->host
->hostt
->skip_settle_delay
)
489 ssleep(HOST_RESET_SETTLE_TIME
);
490 spin_lock_irqsave(scmd
->device
->host
->host_lock
, flags
);
491 scsi_report_bus_reset(scmd
->device
->host
,
493 spin_unlock_irqrestore(scmd
->device
->host
->host_lock
, flags
);
500 * scsi_try_bus_reset - ask host to perform a bus reset
501 * @scmd: SCSI cmd to send bus reset.
503 static int scsi_try_bus_reset(struct scsi_cmnd
*scmd
)
508 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Snd Bus RST\n",
511 if (!scmd
->device
->host
->hostt
->eh_bus_reset_handler
)
514 rtn
= scmd
->device
->host
->hostt
->eh_bus_reset_handler(scmd
);
516 if (rtn
== SUCCESS
) {
517 if (!scmd
->device
->host
->hostt
->skip_settle_delay
)
518 ssleep(BUS_RESET_SETTLE_TIME
);
519 spin_lock_irqsave(scmd
->device
->host
->host_lock
, flags
);
520 scsi_report_bus_reset(scmd
->device
->host
,
522 spin_unlock_irqrestore(scmd
->device
->host
->host_lock
, flags
);
529 * scsi_try_bus_device_reset - Ask host to perform a BDR on a dev
530 * @scmd: SCSI cmd used to send BDR
533 * There is no timeout for this operation. if this operation is
534 * unreliable for a given host, then the host itself needs to put a
535 * timer on it, and set the host back to a consistent state prior to
538 static int scsi_try_bus_device_reset(struct scsi_cmnd
*scmd
)
542 if (!scmd
->device
->host
->hostt
->eh_device_reset_handler
)
545 rtn
= scmd
->device
->host
->hostt
->eh_device_reset_handler(scmd
);
546 if (rtn
== SUCCESS
) {
547 scmd
->device
->was_reset
= 1;
548 scmd
->device
->expecting_cc_ua
= 1;
554 static int __scsi_try_to_abort_cmd(struct scsi_cmnd
*scmd
)
556 if (!scmd
->device
->host
->hostt
->eh_abort_handler
)
559 return scmd
->device
->host
->hostt
->eh_abort_handler(scmd
);
563 * scsi_try_to_abort_cmd - Ask host to abort a running command.
564 * @scmd: SCSI cmd to abort from Lower Level.
567 * This function will not return until the user's completion function
568 * has been called. there is no timeout on this operation. if the
569 * author of the low-level driver wishes this operation to be timed,
570 * they can provide this facility themselves. helper functions in
571 * scsi_error.c can be supplied to make this easier to do.
573 static int scsi_try_to_abort_cmd(struct scsi_cmnd
*scmd
)
576 * scsi_done was called just after the command timed out and before
577 * we had a chance to process it. (db)
579 if (scmd
->serial_number
== 0)
581 return __scsi_try_to_abort_cmd(scmd
);
584 static void scsi_abort_eh_cmnd(struct scsi_cmnd
*scmd
)
586 if (__scsi_try_to_abort_cmd(scmd
) != SUCCESS
)
587 if (scsi_try_bus_device_reset(scmd
) != SUCCESS
)
588 if (scsi_try_bus_reset(scmd
) != SUCCESS
)
589 scsi_try_host_reset(scmd
);
593 * scsi_send_eh_cmnd - submit a scsi command as part of error recory
594 * @scmd: SCSI command structure to hijack
595 * @cmnd: CDB to send. Can be NULL if no new cmnd is needed
596 * @cmnd_size: size in bytes of @cmnd
597 * @timeout: timeout for this request
598 * @sense_bytes: size of sense data to copy. or 0 (if != 0 @cmnd is ignored)
600 * This function is used to send a scsi command down to a target device
601 * as part of the error recovery process. If @sense_bytes is 0 the command
602 * sent must be one that does not transfer any data. If @sense_bytes != 0
603 * @cmnd is ignored and this functions sets up a REQUEST_SENSE command
604 * and cmnd buffers to read @sense_bytes into @scmd->sense_buffer.
607 * SUCCESS or FAILED or NEEDS_RETRY
609 static int scsi_send_eh_cmnd(struct scsi_cmnd
*scmd
, unsigned char *cmnd
,
610 int cmnd_size
, int timeout
, unsigned sense_bytes
)
612 struct scsi_device
*sdev
= scmd
->device
;
613 struct Scsi_Host
*shost
= sdev
->host
;
614 DECLARE_COMPLETION_ONSTACK(done
);
615 unsigned long timeleft
;
618 unsigned char old_cmd_len
;
619 unsigned char old_cmnd
[MAX_COMMAND_SIZE
];
620 enum dma_data_direction old_data_direction
;
621 unsigned old_bufflen
;
623 unsigned short old_use_sg
;
627 struct scatterlist sgl
;
631 * We need saved copies of a number of fields - this is because
632 * error handling may need to overwrite these with different values
633 * to run different commands, and once error handling is complete,
634 * we will need to restore these values prior to running the actual
637 old_cmd_len
= scmd
->cmd_len
;
638 memcpy(old_cmnd
, scmd
->cmnd
, sizeof(scmd
->cmnd
));
639 old_data_direction
= scmd
->sc_data_direction
;
640 old_bufflen
= scmd
->request_bufflen
;
641 old_buffer
= scmd
->request_buffer
;
642 old_use_sg
= scmd
->use_sg
;
643 old_resid
= scmd
->resid
;
644 old_result
= scmd
->result
;
647 scmd
->request_bufflen
= min_t(unsigned,
648 sizeof(scmd
->sense_buffer
), sense_bytes
);
649 sg_init_one(&sgl
, scmd
->sense_buffer
, scmd
->request_bufflen
);
650 scmd
->request_buffer
= &sgl
;
651 scmd
->sc_data_direction
= DMA_FROM_DEVICE
;
653 memset(scmd
->cmnd
, 0, sizeof(scmd
->cmnd
));
654 scmd
->cmnd
[0] = REQUEST_SENSE
;
655 scmd
->cmnd
[4] = scmd
->request_bufflen
;
656 scmd
->cmd_len
= COMMAND_SIZE(scmd
->cmnd
[0]);
658 scmd
->request_buffer
= NULL
;
659 scmd
->request_bufflen
= 0;
660 scmd
->sc_data_direction
= DMA_NONE
;
663 memset(scmd
->cmnd
, 0, sizeof(scmd
->cmnd
));
664 memcpy(scmd
->cmnd
, cmnd
, cmnd_size
);
665 scmd
->cmd_len
= COMMAND_SIZE(scmd
->cmnd
[0]);
671 if (sdev
->scsi_level
<= SCSI_2
&& sdev
->scsi_level
!= SCSI_UNKNOWN
)
672 scmd
->cmnd
[1] = (scmd
->cmnd
[1] & 0x1f) |
673 (sdev
->lun
<< 5 & 0xe0);
676 * Zero the sense buffer. The scsi spec mandates that any
677 * untransferred sense data should be interpreted as being zero.
679 memset(scmd
->sense_buffer
, 0, sizeof(scmd
->sense_buffer
));
681 shost
->eh_action
= &done
;
683 spin_lock_irqsave(shost
->host_lock
, flags
);
685 shost
->hostt
->queuecommand(scmd
, scsi_eh_done
);
686 spin_unlock_irqrestore(shost
->host_lock
, flags
);
688 timeleft
= wait_for_completion_timeout(&done
, timeout
);
690 shost
->eh_action
= NULL
;
692 scsi_log_completion(scmd
, SUCCESS
);
694 SCSI_LOG_ERROR_RECOVERY(3,
695 printk("%s: scmd: %p, timeleft: %ld\n",
696 __FUNCTION__
, scmd
, timeleft
));
699 * If there is time left scsi_eh_done got called, and we will
700 * examine the actual status codes to see whether the command
701 * actually did complete normally, else tell the host to forget
702 * about this command.
705 rtn
= scsi_eh_completed_normally(scmd
);
706 SCSI_LOG_ERROR_RECOVERY(3,
707 printk("%s: scsi_eh_completed_normally %x\n",
720 scsi_abort_eh_cmnd(scmd
);
726 * Restore original data
728 scmd
->cmd_len
= old_cmd_len
;
729 memcpy(scmd
->cmnd
, old_cmnd
, sizeof(scmd
->cmnd
));
730 scmd
->sc_data_direction
= old_data_direction
;
731 scmd
->request_bufflen
= old_bufflen
;
732 scmd
->request_buffer
= old_buffer
;
733 scmd
->use_sg
= old_use_sg
;
734 scmd
->resid
= old_resid
;
735 scmd
->result
= old_result
;
740 * scsi_request_sense - Request sense data from a particular target.
741 * @scmd: SCSI cmd for request sense.
744 * Some hosts automatically obtain this information, others require
745 * that we obtain it on our own. This function will *not* return until
746 * the command either times out, or it completes.
748 static int scsi_request_sense(struct scsi_cmnd
*scmd
)
750 return scsi_send_eh_cmnd(scmd
, NULL
, 0, SENSE_TIMEOUT
, ~0);
754 * scsi_eh_finish_cmd - Handle a cmd that eh is finished with.
755 * @scmd: Original SCSI cmd that eh has finished.
756 * @done_q: Queue for processed commands.
759 * We don't want to use the normal command completion while we are are
760 * still handling errors - it may cause other commands to be queued,
761 * and that would disturb what we are doing. thus we really want to
762 * keep a list of pending commands for final completion, and once we
763 * are ready to leave error handling we handle completion for real.
765 void scsi_eh_finish_cmd(struct scsi_cmnd
*scmd
, struct list_head
*done_q
)
767 scmd
->device
->host
->host_failed
--;
769 list_move_tail(&scmd
->eh_entry
, done_q
);
771 EXPORT_SYMBOL(scsi_eh_finish_cmd
);
774 * scsi_eh_get_sense - Get device sense data.
775 * @work_q: Queue of commands to process.
776 * @done_q: Queue of proccessed commands..
779 * See if we need to request sense information. if so, then get it
780 * now, so we have a better idea of what to do.
783 * This has the unfortunate side effect that if a shost adapter does
784 * not automatically request sense information, that we end up shutting
785 * it down before we request it.
787 * All drivers should request sense information internally these days,
788 * so for now all I have to say is tough noogies if you end up in here.
790 * XXX: Long term this code should go away, but that needs an audit of
793 int scsi_eh_get_sense(struct list_head
*work_q
,
794 struct list_head
*done_q
)
796 struct scsi_cmnd
*scmd
, *next
;
799 list_for_each_entry_safe(scmd
, next
, work_q
, eh_entry
) {
800 if ((scmd
->eh_eflags
& SCSI_EH_CANCEL_CMD
) ||
801 SCSI_SENSE_VALID(scmd
))
804 SCSI_LOG_ERROR_RECOVERY(2, scmd_printk(KERN_INFO
, scmd
,
805 "%s: requesting sense\n",
807 rtn
= scsi_request_sense(scmd
);
811 SCSI_LOG_ERROR_RECOVERY(3, printk("sense requested for %p"
812 " result %x\n", scmd
,
814 SCSI_LOG_ERROR_RECOVERY(3, scsi_print_sense("bh", scmd
));
816 rtn
= scsi_decide_disposition(scmd
);
819 * if the result was normal, then just pass it along to the
823 /* we don't want this command reissued, just
824 * finished with the sense data, so set
825 * retries to the max allowed to ensure it
826 * won't get reissued */
827 scmd
->retries
= scmd
->allowed
;
828 else if (rtn
!= NEEDS_RETRY
)
831 scsi_eh_finish_cmd(scmd
, done_q
);
834 return list_empty(work_q
);
836 EXPORT_SYMBOL_GPL(scsi_eh_get_sense
);
839 * scsi_eh_tur - Send TUR to device.
840 * @scmd: Scsi cmd to send TUR
843 * 0 - Device is ready. 1 - Device NOT ready.
845 static int scsi_eh_tur(struct scsi_cmnd
*scmd
)
847 static unsigned char tur_command
[6] = {TEST_UNIT_READY
, 0, 0, 0, 0, 0};
848 int retry_cnt
= 1, rtn
;
851 rtn
= scsi_send_eh_cmnd(scmd
, tur_command
, 6, SENSE_TIMEOUT
, 0);
853 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: scmd %p rtn %x\n",
854 __FUNCTION__
, scmd
, rtn
));
869 * scsi_eh_abort_cmds - abort canceled commands.
870 * @shost: scsi host being recovered.
871 * @eh_done_q: list_head for processed commands.
874 * Try and see whether or not it makes sense to try and abort the
875 * running command. this only works out to be the case if we have one
876 * command that has timed out. if the command simply failed, it makes
877 * no sense to try and abort the command, since as far as the shost
878 * adapter is concerned, it isn't running.
880 static int scsi_eh_abort_cmds(struct list_head
*work_q
,
881 struct list_head
*done_q
)
883 struct scsi_cmnd
*scmd
, *next
;
886 list_for_each_entry_safe(scmd
, next
, work_q
, eh_entry
) {
887 if (!(scmd
->eh_eflags
& SCSI_EH_CANCEL_CMD
))
889 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: aborting cmd:"
890 "0x%p\n", current
->comm
,
892 rtn
= scsi_try_to_abort_cmd(scmd
);
893 if (rtn
== SUCCESS
) {
894 scmd
->eh_eflags
&= ~SCSI_EH_CANCEL_CMD
;
895 if (!scsi_device_online(scmd
->device
) ||
896 !scsi_eh_tur(scmd
)) {
897 scsi_eh_finish_cmd(scmd
, done_q
);
901 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: aborting"
908 return list_empty(work_q
);
912 * scsi_eh_try_stu - Send START_UNIT to device.
913 * @scmd: Scsi cmd to send START_UNIT
916 * 0 - Device is ready. 1 - Device NOT ready.
918 static int scsi_eh_try_stu(struct scsi_cmnd
*scmd
)
920 static unsigned char stu_command
[6] = {START_STOP
, 0, 0, 0, 1, 0};
922 if (scmd
->device
->allow_restart
) {
923 int i
, rtn
= NEEDS_RETRY
;
925 for (i
= 0; rtn
== NEEDS_RETRY
&& i
< 2; i
++)
926 rtn
= scsi_send_eh_cmnd(scmd
, stu_command
, 6,
927 scmd
->device
->timeout
, 0);
937 * scsi_eh_stu - send START_UNIT if needed
938 * @shost: scsi host being recovered.
939 * @eh_done_q: list_head for processed commands.
942 * If commands are failing due to not ready, initializing command required,
943 * try revalidating the device, which will end up sending a start unit.
945 static int scsi_eh_stu(struct Scsi_Host
*shost
,
946 struct list_head
*work_q
,
947 struct list_head
*done_q
)
949 struct scsi_cmnd
*scmd
, *stu_scmd
, *next
;
950 struct scsi_device
*sdev
;
952 shost_for_each_device(sdev
, shost
) {
954 list_for_each_entry(scmd
, work_q
, eh_entry
)
955 if (scmd
->device
== sdev
&& SCSI_SENSE_VALID(scmd
) &&
956 scsi_check_sense(scmd
) == FAILED
) {
964 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending START_UNIT to sdev:"
965 " 0x%p\n", current
->comm
, sdev
));
967 if (!scsi_eh_try_stu(stu_scmd
)) {
968 if (!scsi_device_online(sdev
) ||
969 !scsi_eh_tur(stu_scmd
)) {
970 list_for_each_entry_safe(scmd
, next
,
972 if (scmd
->device
== sdev
)
973 scsi_eh_finish_cmd(scmd
, done_q
);
977 SCSI_LOG_ERROR_RECOVERY(3,
978 printk("%s: START_UNIT failed to sdev:"
979 " 0x%p\n", current
->comm
, sdev
));
983 return list_empty(work_q
);
988 * scsi_eh_bus_device_reset - send bdr if needed
989 * @shost: scsi host being recovered.
990 * @eh_done_q: list_head for processed commands.
993 * Try a bus device reset. still, look to see whether we have multiple
994 * devices that are jammed or not - if we have multiple devices, it
995 * makes no sense to try bus_device_reset - we really would need to try
996 * a bus_reset instead.
998 static int scsi_eh_bus_device_reset(struct Scsi_Host
*shost
,
999 struct list_head
*work_q
,
1000 struct list_head
*done_q
)
1002 struct scsi_cmnd
*scmd
, *bdr_scmd
, *next
;
1003 struct scsi_device
*sdev
;
1006 shost_for_each_device(sdev
, shost
) {
1008 list_for_each_entry(scmd
, work_q
, eh_entry
)
1009 if (scmd
->device
== sdev
) {
1017 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending BDR sdev:"
1018 " 0x%p\n", current
->comm
,
1020 rtn
= scsi_try_bus_device_reset(bdr_scmd
);
1021 if (rtn
== SUCCESS
) {
1022 if (!scsi_device_online(sdev
) ||
1023 !scsi_eh_tur(bdr_scmd
)) {
1024 list_for_each_entry_safe(scmd
, next
,
1026 if (scmd
->device
== sdev
)
1027 scsi_eh_finish_cmd(scmd
,
1032 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: BDR"
1040 return list_empty(work_q
);
1044 * scsi_eh_bus_reset - send a bus reset
1045 * @shost: scsi host being recovered.
1046 * @eh_done_q: list_head for processed commands.
1048 static int scsi_eh_bus_reset(struct Scsi_Host
*shost
,
1049 struct list_head
*work_q
,
1050 struct list_head
*done_q
)
1052 struct scsi_cmnd
*scmd
, *chan_scmd
, *next
;
1053 unsigned int channel
;
1057 * we really want to loop over the various channels, and do this on
1058 * a channel by channel basis. we should also check to see if any
1059 * of the failed commands are on soft_reset devices, and if so, skip
1063 for (channel
= 0; channel
<= shost
->max_channel
; channel
++) {
1065 list_for_each_entry(scmd
, work_q
, eh_entry
) {
1066 if (channel
== scmd_channel(scmd
)) {
1070 * FIXME add back in some support for
1071 * soft_reset devices.
1078 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending BRST chan:"
1079 " %d\n", current
->comm
,
1081 rtn
= scsi_try_bus_reset(chan_scmd
);
1082 if (rtn
== SUCCESS
) {
1083 list_for_each_entry_safe(scmd
, next
, work_q
, eh_entry
) {
1084 if (channel
== scmd_channel(scmd
))
1085 if (!scsi_device_online(scmd
->device
) ||
1087 scsi_eh_finish_cmd(scmd
,
1091 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: BRST"
1092 " failed chan: %d\n",
1097 return list_empty(work_q
);
1101 * scsi_eh_host_reset - send a host reset
1102 * @work_q: list_head for processed commands.
1103 * @done_q: list_head for processed commands.
1105 static int scsi_eh_host_reset(struct list_head
*work_q
,
1106 struct list_head
*done_q
)
1108 struct scsi_cmnd
*scmd
, *next
;
1111 if (!list_empty(work_q
)) {
1112 scmd
= list_entry(work_q
->next
,
1113 struct scsi_cmnd
, eh_entry
);
1115 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending HRST\n"
1118 rtn
= scsi_try_host_reset(scmd
);
1119 if (rtn
== SUCCESS
) {
1120 list_for_each_entry_safe(scmd
, next
, work_q
, eh_entry
) {
1121 if (!scsi_device_online(scmd
->device
) ||
1122 (!scsi_eh_try_stu(scmd
) && !scsi_eh_tur(scmd
)) ||
1124 scsi_eh_finish_cmd(scmd
, done_q
);
1127 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: HRST"
1132 return list_empty(work_q
);
1136 * scsi_eh_offline_sdevs - offline scsi devices that fail to recover
1137 * @work_q: list_head for processed commands.
1138 * @done_q: list_head for processed commands.
1141 static void scsi_eh_offline_sdevs(struct list_head
*work_q
,
1142 struct list_head
*done_q
)
1144 struct scsi_cmnd
*scmd
, *next
;
1146 list_for_each_entry_safe(scmd
, next
, work_q
, eh_entry
) {
1147 sdev_printk(KERN_INFO
, scmd
->device
, "Device offlined - "
1148 "not ready after error recovery\n");
1149 scsi_device_set_state(scmd
->device
, SDEV_OFFLINE
);
1150 if (scmd
->eh_eflags
& SCSI_EH_CANCEL_CMD
) {
1152 * FIXME: Handle lost cmds.
1155 scsi_eh_finish_cmd(scmd
, done_q
);
1161 * scsi_decide_disposition - Disposition a cmd on return from LLD.
1162 * @scmd: SCSI cmd to examine.
1165 * This is *only* called when we are examining the status after sending
1166 * out the actual data command. any commands that are queued for error
1167 * recovery (e.g. test_unit_ready) do *not* come through here.
1169 * When this routine returns failed, it means the error handler thread
1170 * is woken. In cases where the error code indicates an error that
1171 * doesn't require the error handler read (i.e. we don't need to
1172 * abort/reset), this function should return SUCCESS.
1174 int scsi_decide_disposition(struct scsi_cmnd
*scmd
)
1179 * if the device is offline, then we clearly just pass the result back
1180 * up to the top level.
1182 if (!scsi_device_online(scmd
->device
)) {
1183 SCSI_LOG_ERROR_RECOVERY(5, printk("%s: device offline - report"
1190 * first check the host byte, to see if there is anything in there
1191 * that would indicate what we need to do.
1193 switch (host_byte(scmd
->result
)) {
1194 case DID_PASSTHROUGH
:
1196 * no matter what, pass this through to the upper layer.
1197 * nuke this special code so that it looks like we are saying
1200 scmd
->result
&= 0xff00ffff;
1204 * looks good. drop through, and check the next byte.
1207 case DID_NO_CONNECT
:
1208 case DID_BAD_TARGET
:
1211 * note - this means that we just report the status back
1212 * to the top level driver, not that we actually think
1213 * that it indicates SUCCESS.
1217 * when the low level driver returns did_soft_error,
1218 * it is responsible for keeping an internal retry counter
1219 * in order to avoid endless loops (db)
1221 * actually this is a bug in this function here. we should
1222 * be mindful of the maximum number of retries specified
1223 * and not get stuck in a loop.
1225 case DID_SOFT_ERROR
:
1231 return ADD_TO_MLQUEUE
;
1234 if (msg_byte(scmd
->result
) == COMMAND_COMPLETE
&&
1235 status_byte(scmd
->result
) == RESERVATION_CONFLICT
)
1237 * execute reservation conflict processing code
1248 * when we scan the bus, we get timeout messages for
1249 * these commands if there is no device available.
1250 * other hosts report did_no_connect for the same thing.
1252 if ((scmd
->cmnd
[0] == TEST_UNIT_READY
||
1253 scmd
->cmnd
[0] == INQUIRY
)) {
1265 * next, check the message byte.
1267 if (msg_byte(scmd
->result
) != COMMAND_COMPLETE
)
1271 * check the status byte to see if this indicates anything special.
1273 switch (status_byte(scmd
->result
)) {
1276 * the case of trying to send too many commands to a
1277 * tagged queueing device.
1281 * device can't talk to us at the moment. Should only
1282 * occur (SAM-3) when the task queue is empty, so will cause
1283 * the empty queue handling to trigger a stall in the
1286 return ADD_TO_MLQUEUE
;
1288 case COMMAND_TERMINATED
:
1291 case CHECK_CONDITION
:
1292 rtn
= scsi_check_sense(scmd
);
1293 if (rtn
== NEEDS_RETRY
)
1295 /* if rtn == FAILED, we have no sense information;
1296 * returning FAILED will wake the error handler thread
1297 * to collect the sense and redo the decide
1300 case CONDITION_GOOD
:
1301 case INTERMEDIATE_GOOD
:
1302 case INTERMEDIATE_C_GOOD
:
1305 * who knows? FIXME(eric)
1309 case RESERVATION_CONFLICT
:
1310 sdev_printk(KERN_INFO
, scmd
->device
,
1311 "reservation conflict\n");
1312 return SUCCESS
; /* causes immediate i/o error */
1320 /* we requeue for retry because the error was retryable, and
1321 * the request was not marked fast fail. Note that above,
1322 * even if the request is marked fast fail, we still requeue
1323 * for queue congestion conditions (QUEUE_FULL or BUSY) */
1324 if ((++scmd
->retries
) <= scmd
->allowed
1325 && !blk_noretry_request(scmd
->request
)) {
1329 * no more retries - report this one back to upper level.
1336 * scsi_eh_lock_door - Prevent medium removal for the specified device
1337 * @sdev: SCSI device to prevent medium removal
1340 * We must be called from process context; scsi_allocate_request()
1344 * We queue up an asynchronous "ALLOW MEDIUM REMOVAL" request on the
1345 * head of the devices request queue, and continue.
1348 * scsi_allocate_request() may sleep waiting for existing requests to
1349 * be processed. However, since we haven't kicked off any request
1350 * processing for this host, this may deadlock.
1352 * If scsi_allocate_request() fails for what ever reason, we
1353 * completely forget to lock the door.
1355 static void scsi_eh_lock_door(struct scsi_device
*sdev
)
1357 unsigned char cmnd
[MAX_COMMAND_SIZE
];
1359 cmnd
[0] = ALLOW_MEDIUM_REMOVAL
;
1363 cmnd
[4] = SCSI_REMOVAL_PREVENT
;
1366 scsi_execute_async(sdev
, cmnd
, 6, DMA_NONE
, NULL
, 0, 0, 10 * HZ
,
1367 5, NULL
, NULL
, GFP_KERNEL
);
1372 * scsi_restart_operations - restart io operations to the specified host.
1373 * @shost: Host we are restarting.
1376 * When we entered the error handler, we blocked all further i/o to
1377 * this device. we need to 'reverse' this process.
1379 static void scsi_restart_operations(struct Scsi_Host
*shost
)
1381 struct scsi_device
*sdev
;
1382 unsigned long flags
;
1385 * If the door was locked, we need to insert a door lock request
1386 * onto the head of the SCSI request queue for the device. There
1387 * is no point trying to lock the door of an off-line device.
1389 shost_for_each_device(sdev
, shost
) {
1390 if (scsi_device_online(sdev
) && sdev
->locked
)
1391 scsi_eh_lock_door(sdev
);
1395 * next free up anything directly waiting upon the host. this
1396 * will be requests for character device operations, and also for
1397 * ioctls to queued block devices.
1399 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: waking up host to restart\n",
1402 spin_lock_irqsave(shost
->host_lock
, flags
);
1403 if (scsi_host_set_state(shost
, SHOST_RUNNING
))
1404 if (scsi_host_set_state(shost
, SHOST_CANCEL
))
1405 BUG_ON(scsi_host_set_state(shost
, SHOST_DEL
));
1406 spin_unlock_irqrestore(shost
->host_lock
, flags
);
1408 wake_up(&shost
->host_wait
);
1411 * finally we need to re-initiate requests that may be pending. we will
1412 * have had everything blocked while error handling is taking place, and
1413 * now that error recovery is done, we will need to ensure that these
1414 * requests are started.
1416 scsi_run_host_queues(shost
);
1420 * scsi_eh_ready_devs - check device ready state and recover if not.
1421 * @shost: host to be recovered.
1422 * @eh_done_q: list_head for processed commands.
1425 void scsi_eh_ready_devs(struct Scsi_Host
*shost
,
1426 struct list_head
*work_q
,
1427 struct list_head
*done_q
)
1429 if (!scsi_eh_stu(shost
, work_q
, done_q
))
1430 if (!scsi_eh_bus_device_reset(shost
, work_q
, done_q
))
1431 if (!scsi_eh_bus_reset(shost
, work_q
, done_q
))
1432 if (!scsi_eh_host_reset(work_q
, done_q
))
1433 scsi_eh_offline_sdevs(work_q
, done_q
);
1435 EXPORT_SYMBOL_GPL(scsi_eh_ready_devs
);
1438 * scsi_eh_flush_done_q - finish processed commands or retry them.
1439 * @done_q: list_head of processed commands.
1442 void scsi_eh_flush_done_q(struct list_head
*done_q
)
1444 struct scsi_cmnd
*scmd
, *next
;
1446 list_for_each_entry_safe(scmd
, next
, done_q
, eh_entry
) {
1447 list_del_init(&scmd
->eh_entry
);
1448 if (scsi_device_online(scmd
->device
) &&
1449 !blk_noretry_request(scmd
->request
) &&
1450 (++scmd
->retries
<= scmd
->allowed
)) {
1451 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: flush"
1455 scsi_queue_insert(scmd
, SCSI_MLQUEUE_EH_RETRY
);
1458 * If just we got sense for the device (called
1459 * scsi_eh_get_sense), scmd->result is already
1460 * set, do not set DRIVER_TIMEOUT.
1463 scmd
->result
|= (DRIVER_TIMEOUT
<< 24);
1464 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: flush finish"
1466 current
->comm
, scmd
));
1467 scsi_finish_command(scmd
);
1471 EXPORT_SYMBOL(scsi_eh_flush_done_q
);
1474 * scsi_unjam_host - Attempt to fix a host which has a cmd that failed.
1475 * @shost: Host to unjam.
1478 * When we come in here, we *know* that all commands on the bus have
1479 * either completed, failed or timed out. we also know that no further
1480 * commands are being sent to the host, so things are relatively quiet
1481 * and we have freedom to fiddle with things as we wish.
1483 * This is only the *default* implementation. it is possible for
1484 * individual drivers to supply their own version of this function, and
1485 * if the maintainer wishes to do this, it is strongly suggested that
1486 * this function be taken as a template and modified. this function
1487 * was designed to correctly handle problems for about 95% of the
1488 * different cases out there, and it should always provide at least a
1489 * reasonable amount of error recovery.
1491 * Any command marked 'failed' or 'timeout' must eventually have
1492 * scsi_finish_cmd() called for it. we do all of the retry stuff
1493 * here, so when we restart the host after we return it should have an
1496 static void scsi_unjam_host(struct Scsi_Host
*shost
)
1498 unsigned long flags
;
1499 LIST_HEAD(eh_work_q
);
1500 LIST_HEAD(eh_done_q
);
1502 spin_lock_irqsave(shost
->host_lock
, flags
);
1503 list_splice_init(&shost
->eh_cmd_q
, &eh_work_q
);
1504 spin_unlock_irqrestore(shost
->host_lock
, flags
);
1506 SCSI_LOG_ERROR_RECOVERY(1, scsi_eh_prt_fail_stats(shost
, &eh_work_q
));
1508 if (!scsi_eh_get_sense(&eh_work_q
, &eh_done_q
))
1509 if (!scsi_eh_abort_cmds(&eh_work_q
, &eh_done_q
))
1510 scsi_eh_ready_devs(shost
, &eh_work_q
, &eh_done_q
);
1512 scsi_eh_flush_done_q(&eh_done_q
);
1516 * scsi_error_handler - SCSI error handler thread
1517 * @data: Host for which we are running.
1520 * This is the main error handling loop. This is run as a kernel thread
1521 * for every SCSI host and handles all error handling activity.
1523 int scsi_error_handler(void *data
)
1525 struct Scsi_Host
*shost
= data
;
1528 * We use TASK_INTERRUPTIBLE so that the thread is not
1529 * counted against the load average as a running process.
1530 * We never actually get interrupted because kthread_run
1531 * disables singal delivery for the created thread.
1533 set_current_state(TASK_INTERRUPTIBLE
);
1534 while (!kthread_should_stop()) {
1535 if ((shost
->host_failed
== 0 && shost
->host_eh_scheduled
== 0) ||
1536 shost
->host_failed
!= shost
->host_busy
) {
1537 SCSI_LOG_ERROR_RECOVERY(1,
1538 printk("Error handler scsi_eh_%d sleeping\n",
1541 set_current_state(TASK_INTERRUPTIBLE
);
1545 __set_current_state(TASK_RUNNING
);
1546 SCSI_LOG_ERROR_RECOVERY(1,
1547 printk("Error handler scsi_eh_%d waking up\n",
1551 * We have a host that is failing for some reason. Figure out
1552 * what we need to do to get it up and online again (if we can).
1553 * If we fail, we end up taking the thing offline.
1555 if (shost
->transportt
->eh_strategy_handler
)
1556 shost
->transportt
->eh_strategy_handler(shost
);
1558 scsi_unjam_host(shost
);
1561 * Note - if the above fails completely, the action is to take
1562 * individual devices offline and flush the queue of any
1563 * outstanding requests that may have been pending. When we
1564 * restart, we restart any I/O to any other devices on the bus
1565 * which are still online.
1567 scsi_restart_operations(shost
);
1568 set_current_state(TASK_INTERRUPTIBLE
);
1570 __set_current_state(TASK_RUNNING
);
1572 SCSI_LOG_ERROR_RECOVERY(1,
1573 printk("Error handler scsi_eh_%d exiting\n", shost
->host_no
));
1574 shost
->ehandler
= NULL
;
1579 * Function: scsi_report_bus_reset()
1581 * Purpose: Utility function used by low-level drivers to report that
1582 * they have observed a bus reset on the bus being handled.
1584 * Arguments: shost - Host in question
1585 * channel - channel on which reset was observed.
1589 * Lock status: Host lock must be held.
1591 * Notes: This only needs to be called if the reset is one which
1592 * originates from an unknown location. Resets originated
1593 * by the mid-level itself don't need to call this, but there
1594 * should be no harm.
1596 * The main purpose of this is to make sure that a CHECK_CONDITION
1597 * is properly treated.
1599 void scsi_report_bus_reset(struct Scsi_Host
*shost
, int channel
)
1601 struct scsi_device
*sdev
;
1603 __shost_for_each_device(sdev
, shost
) {
1604 if (channel
== sdev_channel(sdev
)) {
1605 sdev
->was_reset
= 1;
1606 sdev
->expecting_cc_ua
= 1;
1610 EXPORT_SYMBOL(scsi_report_bus_reset
);
1613 * Function: scsi_report_device_reset()
1615 * Purpose: Utility function used by low-level drivers to report that
1616 * they have observed a device reset on the device being handled.
1618 * Arguments: shost - Host in question
1619 * channel - channel on which reset was observed
1620 * target - target on which reset was observed
1624 * Lock status: Host lock must be held
1626 * Notes: This only needs to be called if the reset is one which
1627 * originates from an unknown location. Resets originated
1628 * by the mid-level itself don't need to call this, but there
1629 * should be no harm.
1631 * The main purpose of this is to make sure that a CHECK_CONDITION
1632 * is properly treated.
1634 void scsi_report_device_reset(struct Scsi_Host
*shost
, int channel
, int target
)
1636 struct scsi_device
*sdev
;
1638 __shost_for_each_device(sdev
, shost
) {
1639 if (channel
== sdev_channel(sdev
) &&
1640 target
== sdev_id(sdev
)) {
1641 sdev
->was_reset
= 1;
1642 sdev
->expecting_cc_ua
= 1;
1646 EXPORT_SYMBOL(scsi_report_device_reset
);
1649 scsi_reset_provider_done_command(struct scsi_cmnd
*scmd
)
1654 * Function: scsi_reset_provider
1656 * Purpose: Send requested reset to a bus or device at any phase.
1658 * Arguments: device - device to send reset to
1659 * flag - reset type (see scsi.h)
1661 * Returns: SUCCESS/FAILURE.
1663 * Notes: This is used by the SCSI Generic driver to provide
1664 * Bus/Device reset capability.
1667 scsi_reset_provider(struct scsi_device
*dev
, int flag
)
1669 struct scsi_cmnd
*scmd
= scsi_get_command(dev
, GFP_KERNEL
);
1670 struct Scsi_Host
*shost
= dev
->host
;
1672 unsigned long flags
;
1675 scmd
->request
= &req
;
1676 memset(&scmd
->eh_timeout
, 0, sizeof(scmd
->eh_timeout
));
1678 memset(&scmd
->cmnd
, '\0', sizeof(scmd
->cmnd
));
1680 scmd
->scsi_done
= scsi_reset_provider_done_command
;
1681 scmd
->request_buffer
= NULL
;
1682 scmd
->request_bufflen
= 0;
1686 scmd
->sc_data_direction
= DMA_BIDIRECTIONAL
;
1688 init_timer(&scmd
->eh_timeout
);
1690 spin_lock_irqsave(shost
->host_lock
, flags
);
1691 shost
->tmf_in_progress
= 1;
1692 spin_unlock_irqrestore(shost
->host_lock
, flags
);
1695 case SCSI_TRY_RESET_DEVICE
:
1696 rtn
= scsi_try_bus_device_reset(scmd
);
1700 case SCSI_TRY_RESET_BUS
:
1701 rtn
= scsi_try_bus_reset(scmd
);
1705 case SCSI_TRY_RESET_HOST
:
1706 rtn
= scsi_try_host_reset(scmd
);
1712 spin_lock_irqsave(shost
->host_lock
, flags
);
1713 shost
->tmf_in_progress
= 0;
1714 spin_unlock_irqrestore(shost
->host_lock
, flags
);
1717 * be sure to wake up anyone who was sleeping or had their queue
1718 * suspended while we performed the TMF.
1720 SCSI_LOG_ERROR_RECOVERY(3,
1721 printk("%s: waking up host to restart after TMF\n",
1724 wake_up(&shost
->host_wait
);
1726 scsi_run_host_queues(shost
);
1728 scsi_next_command(scmd
);
1731 EXPORT_SYMBOL(scsi_reset_provider
);
1734 * scsi_normalize_sense - normalize main elements from either fixed or
1735 * descriptor sense data format into a common format.
1737 * @sense_buffer: byte array containing sense data returned by device
1738 * @sb_len: number of valid bytes in sense_buffer
1739 * @sshdr: pointer to instance of structure that common
1740 * elements are written to.
1743 * The "main elements" from sense data are: response_code, sense_key,
1744 * asc, ascq and additional_length (only for descriptor format).
1746 * Typically this function can be called after a device has
1747 * responded to a SCSI command with the CHECK_CONDITION status.
1750 * 1 if valid sense data information found, else 0;
1752 int scsi_normalize_sense(const u8
*sense_buffer
, int sb_len
,
1753 struct scsi_sense_hdr
*sshdr
)
1755 if (!sense_buffer
|| !sb_len
)
1758 memset(sshdr
, 0, sizeof(struct scsi_sense_hdr
));
1760 sshdr
->response_code
= (sense_buffer
[0] & 0x7f);
1762 if (!scsi_sense_valid(sshdr
))
1765 if (sshdr
->response_code
>= 0x72) {
1770 sshdr
->sense_key
= (sense_buffer
[1] & 0xf);
1772 sshdr
->asc
= sense_buffer
[2];
1774 sshdr
->ascq
= sense_buffer
[3];
1776 sshdr
->additional_length
= sense_buffer
[7];
1782 sshdr
->sense_key
= (sense_buffer
[2] & 0xf);
1784 sb_len
= (sb_len
< (sense_buffer
[7] + 8)) ?
1785 sb_len
: (sense_buffer
[7] + 8);
1787 sshdr
->asc
= sense_buffer
[12];
1789 sshdr
->ascq
= sense_buffer
[13];
1795 EXPORT_SYMBOL(scsi_normalize_sense
);
1797 int scsi_command_normalize_sense(struct scsi_cmnd
*cmd
,
1798 struct scsi_sense_hdr
*sshdr
)
1800 return scsi_normalize_sense(cmd
->sense_buffer
,
1801 sizeof(cmd
->sense_buffer
), sshdr
);
1803 EXPORT_SYMBOL(scsi_command_normalize_sense
);
1806 * scsi_sense_desc_find - search for a given descriptor type in
1807 * descriptor sense data format.
1809 * @sense_buffer: byte array of descriptor format sense data
1810 * @sb_len: number of valid bytes in sense_buffer
1811 * @desc_type: value of descriptor type to find
1812 * (e.g. 0 -> information)
1815 * only valid when sense data is in descriptor format
1818 * pointer to start of (first) descriptor if found else NULL
1820 const u8
* scsi_sense_desc_find(const u8
* sense_buffer
, int sb_len
,
1823 int add_sen_len
, add_len
, desc_len
, k
;
1826 if ((sb_len
< 8) || (0 == (add_sen_len
= sense_buffer
[7])))
1828 if ((sense_buffer
[0] < 0x72) || (sense_buffer
[0] > 0x73))
1830 add_sen_len
= (add_sen_len
< (sb_len
- 8)) ?
1831 add_sen_len
: (sb_len
- 8);
1832 descp
= &sense_buffer
[8];
1833 for (desc_len
= 0, k
= 0; k
< add_sen_len
; k
+= desc_len
) {
1835 add_len
= (k
< (add_sen_len
- 1)) ? descp
[1]: -1;
1836 desc_len
= add_len
+ 2;
1837 if (descp
[0] == desc_type
)
1839 if (add_len
< 0) // short descriptor ??
1844 EXPORT_SYMBOL(scsi_sense_desc_find
);
1847 * scsi_get_sense_info_fld - attempts to get information field from
1848 * sense data (either fixed or descriptor format)
1850 * @sense_buffer: byte array of sense data
1851 * @sb_len: number of valid bytes in sense_buffer
1852 * @info_out: pointer to 64 integer where 8 or 4 byte information
1853 * field will be placed if found.
1856 * 1 if information field found, 0 if not found.
1858 int scsi_get_sense_info_fld(const u8
* sense_buffer
, int sb_len
,
1867 switch (sense_buffer
[0] & 0x7f) {
1870 if (sense_buffer
[0] & 0x80) {
1871 *info_out
= (sense_buffer
[3] << 24) +
1872 (sense_buffer
[4] << 16) +
1873 (sense_buffer
[5] << 8) + sense_buffer
[6];
1879 ucp
= scsi_sense_desc_find(sense_buffer
, sb_len
,
1881 if (ucp
&& (0xa == ucp
[1])) {
1883 for (j
= 0; j
< 8; ++j
) {
1896 EXPORT_SYMBOL(scsi_get_sense_info_fld
);