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_dbg.h>
30 #include <scsi/scsi_device.h>
31 #include <scsi/scsi_eh.h>
32 #include <scsi/scsi_host.h>
33 #include <scsi/scsi_ioctl.h>
34 #include <scsi/scsi_request.h>
36 #include "scsi_priv.h"
37 #include "scsi_logging.h"
39 #define SENSE_TIMEOUT (10*HZ)
40 #define START_UNIT_TIMEOUT (30*HZ)
43 * These should *probably* be handled by the host itself.
44 * Since it is allowed to sleep, it probably should.
46 #define BUS_RESET_SETTLE_TIME (10)
47 #define HOST_RESET_SETTLE_TIME (10)
49 /* called with shost->host_lock held */
50 void scsi_eh_wakeup(struct Scsi_Host
*shost
)
52 if (shost
->host_busy
== shost
->host_failed
) {
53 wake_up_process(shost
->ehandler
);
54 SCSI_LOG_ERROR_RECOVERY(5,
55 printk("Waking error handler thread\n"));
60 * scsi_eh_scmd_add - add scsi cmd to error handling.
61 * @scmd: scmd to run eh on.
62 * @eh_flag: optional SCSI_EH flag.
67 int scsi_eh_scmd_add(struct scsi_cmnd
*scmd
, int eh_flag
)
69 struct Scsi_Host
*shost
= scmd
->device
->host
;
76 spin_lock_irqsave(shost
->host_lock
, flags
);
77 if (scsi_host_set_state(shost
, SHOST_RECOVERY
))
78 if (scsi_host_set_state(shost
, SHOST_CANCEL_RECOVERY
))
82 scmd
->eh_eflags
|= eh_flag
;
83 list_add_tail(&scmd
->eh_entry
, &shost
->eh_cmd_q
);
85 scsi_eh_wakeup(shost
);
87 spin_unlock_irqrestore(shost
->host_lock
, flags
);
92 * scsi_add_timer - Start timeout timer for a single scsi command.
93 * @scmd: scsi command that is about to start running.
94 * @timeout: amount of time to allow this command to run.
95 * @complete: timeout function to call if timer isn't canceled.
98 * This should be turned into an inline function. Each scsi command
99 * has its own timer, and as it is added to the queue, we set up the
100 * timer. When the command completes, we cancel the timer.
102 void scsi_add_timer(struct scsi_cmnd
*scmd
, int timeout
,
103 void (*complete
)(struct scsi_cmnd
*))
107 * If the clock was already running for this command, then
108 * first delete the timer. The timer handling code gets rather
109 * confused if we don't do this.
111 if (scmd
->eh_timeout
.function
)
112 del_timer(&scmd
->eh_timeout
);
114 scmd
->eh_timeout
.data
= (unsigned long)scmd
;
115 scmd
->eh_timeout
.expires
= jiffies
+ timeout
;
116 scmd
->eh_timeout
.function
= (void (*)(unsigned long)) complete
;
118 SCSI_LOG_ERROR_RECOVERY(5, printk("%s: scmd: %p, time:"
119 " %d, (%p)\n", __FUNCTION__
,
120 scmd
, timeout
, complete
));
122 add_timer(&scmd
->eh_timeout
);
126 * scsi_delete_timer - Delete/cancel timer for a given function.
127 * @scmd: Cmd that we are canceling timer for
130 * This should be turned into an inline function.
133 * 1 if we were able to detach the timer. 0 if we blew it, and the
134 * timer function has already started to run.
136 int scsi_delete_timer(struct scsi_cmnd
*scmd
)
140 rtn
= del_timer(&scmd
->eh_timeout
);
142 SCSI_LOG_ERROR_RECOVERY(5, printk("%s: scmd: %p,"
143 " rtn: %d\n", __FUNCTION__
,
146 scmd
->eh_timeout
.data
= (unsigned long)NULL
;
147 scmd
->eh_timeout
.function
= NULL
;
153 * scsi_times_out - Timeout function for normal scsi commands.
154 * @scmd: Cmd that is timing out.
157 * We do not need to lock this. There is the potential for a race
158 * only in that the normal completion handling might run, but if the
159 * normal completion function determines that the timer has already
160 * fired, then it mustn't do anything.
162 void scsi_times_out(struct scsi_cmnd
*scmd
)
164 scsi_log_completion(scmd
, TIMEOUT_ERROR
);
166 if (scmd
->device
->host
->hostt
->eh_timed_out
)
167 switch (scmd
->device
->host
->hostt
->eh_timed_out(scmd
)) {
172 /* This allows a single retry even of a command
173 * with allowed == 0 */
174 if (scmd
->retries
++ > scmd
->allowed
)
176 scsi_add_timer(scmd
, scmd
->timeout_per_command
,
183 if (unlikely(!scsi_eh_scmd_add(scmd
, SCSI_EH_CANCEL_CMD
))) {
184 scmd
->result
|= DID_TIME_OUT
<< 16;
190 * scsi_block_when_processing_errors - Prevent cmds from being queued.
191 * @sdev: Device on which we are performing recovery.
194 * We block until the host is out of error recovery, and then check to
195 * see whether the host or the device is offline.
198 * 0 when dev was taken offline by error recovery. 1 OK to proceed.
200 int scsi_block_when_processing_errors(struct scsi_device
*sdev
)
204 wait_event(sdev
->host
->host_wait
, !scsi_host_in_recovery(sdev
->host
));
206 online
= scsi_device_online(sdev
);
208 SCSI_LOG_ERROR_RECOVERY(5, printk("%s: rtn: %d\n", __FUNCTION__
,
213 EXPORT_SYMBOL(scsi_block_when_processing_errors
);
215 #ifdef CONFIG_SCSI_LOGGING
217 * scsi_eh_prt_fail_stats - Log info on failures.
218 * @shost: scsi host being recovered.
219 * @work_q: Queue of scsi cmds to process.
221 static inline void scsi_eh_prt_fail_stats(struct Scsi_Host
*shost
,
222 struct list_head
*work_q
)
224 struct scsi_cmnd
*scmd
;
225 struct scsi_device
*sdev
;
226 int total_failures
= 0;
229 int devices_failed
= 0;
231 shost_for_each_device(sdev
, shost
) {
232 list_for_each_entry(scmd
, work_q
, eh_entry
) {
233 if (scmd
->device
== sdev
) {
235 if (scmd
->eh_eflags
& SCSI_EH_CANCEL_CMD
)
242 if (cmd_cancel
|| cmd_failed
) {
243 SCSI_LOG_ERROR_RECOVERY(3,
244 sdev_printk(KERN_INFO
, sdev
,
245 "%s: cmds failed: %d, cancel: %d\n",
246 __FUNCTION__
, cmd_failed
,
254 SCSI_LOG_ERROR_RECOVERY(2, printk("Total of %d commands on %d"
255 " devices require eh work\n",
256 total_failures
, devices_failed
));
261 * scsi_check_sense - Examine scsi cmd sense
262 * @scmd: Cmd to have sense checked.
265 * SUCCESS or FAILED or NEEDS_RETRY
268 * When a deferred error is detected the current command has
269 * not been executed and needs retrying.
271 static int scsi_check_sense(struct scsi_cmnd
*scmd
)
273 struct scsi_sense_hdr sshdr
;
275 if (! scsi_command_normalize_sense(scmd
, &sshdr
))
276 return FAILED
; /* no valid sense data */
278 if (scsi_sense_is_deferred(&sshdr
))
282 * Previous logic looked for FILEMARK, EOM or ILI which are
283 * mainly associated with tapes and returned SUCCESS.
285 if (sshdr
.response_code
== 0x70) {
287 if (scmd
->sense_buffer
[2] & 0xe0)
291 * descriptor format: look for "stream commands sense data
292 * descriptor" (see SSC-3). Assume single sense data
293 * descriptor. Ignore ILI from SBC-2 READ LONG and WRITE LONG.
295 if ((sshdr
.additional_length
> 3) &&
296 (scmd
->sense_buffer
[8] == 0x4) &&
297 (scmd
->sense_buffer
[11] & 0xe0))
301 switch (sshdr
.sense_key
) {
304 case RECOVERED_ERROR
:
305 return /* soft_error */ SUCCESS
;
307 case ABORTED_COMMAND
:
312 * if we are expecting a cc/ua because of a bus reset that we
313 * performed, treat this just as a retry. otherwise this is
314 * information that we should pass up to the upper-level driver
315 * so that we can deal with it there.
317 if (scmd
->device
->expecting_cc_ua
) {
318 scmd
->device
->expecting_cc_ua
= 0;
322 * if the device is in the process of becoming ready, we
325 if ((sshdr
.asc
== 0x04) && (sshdr
.ascq
== 0x01))
328 * if the device is not started, we need to wake
329 * the error handler to start the motor
331 if (scmd
->device
->allow_restart
&&
332 (sshdr
.asc
== 0x04) && (sshdr
.ascq
== 0x02))
336 /* these three are not supported */
338 case VOLUME_OVERFLOW
:
346 if (scmd
->device
->retry_hwerror
)
351 case ILLEGAL_REQUEST
:
360 * scsi_eh_completed_normally - Disposition a eh cmd on return from LLD.
361 * @scmd: SCSI cmd to examine.
364 * This is *only* called when we are examining the status of commands
365 * queued during error recovery. the main difference here is that we
366 * don't allow for the possibility of retries here, and we are a lot
367 * more restrictive about what we consider acceptable.
369 static int scsi_eh_completed_normally(struct scsi_cmnd
*scmd
)
372 * first check the host byte, to see if there is anything in there
373 * that would indicate what we need to do.
375 if (host_byte(scmd
->result
) == DID_RESET
) {
377 * rats. we are already in the error handler, so we now
378 * get to try and figure out what to do next. if the sense
379 * is valid, we have a pretty good idea of what to do.
380 * if not, we mark it as FAILED.
382 return scsi_check_sense(scmd
);
384 if (host_byte(scmd
->result
) != DID_OK
)
388 * next, check the message byte.
390 if (msg_byte(scmd
->result
) != COMMAND_COMPLETE
)
394 * now, check the status byte to see if this indicates
397 switch (status_byte(scmd
->result
)) {
399 case COMMAND_TERMINATED
:
401 case CHECK_CONDITION
:
402 return scsi_check_sense(scmd
);
404 case INTERMEDIATE_GOOD
:
405 case INTERMEDIATE_C_GOOD
:
407 * who knows? FIXME(eric)
412 case RESERVATION_CONFLICT
:
420 * scsi_eh_times_out - timeout function for error handling.
421 * @scmd: Cmd that is timing out.
424 * During error handling, the kernel thread will be sleeping waiting
425 * for some action to complete on the device. our only job is to
426 * record that it timed out, and to wake up the thread.
428 static void scsi_eh_times_out(struct scsi_cmnd
*scmd
)
430 scmd
->eh_eflags
|= SCSI_EH_REC_TIMEOUT
;
431 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: scmd:%p\n", __FUNCTION__
,
434 up(scmd
->device
->host
->eh_action
);
438 * scsi_eh_done - Completion function for error handling.
439 * @scmd: Cmd that is done.
441 static void scsi_eh_done(struct scsi_cmnd
*scmd
)
444 * if the timeout handler is already running, then just set the
445 * flag which says we finished late, and return. we have no
446 * way of stopping the timeout handler from running, so we must
447 * always defer to it.
449 if (del_timer(&scmd
->eh_timeout
)) {
450 scmd
->request
->rq_status
= RQ_SCSI_DONE
;
452 SCSI_LOG_ERROR_RECOVERY(3, printk("%s scmd: %p result: %x\n",
453 __FUNCTION__
, scmd
, scmd
->result
));
455 up(scmd
->device
->host
->eh_action
);
460 * scsi_send_eh_cmnd - send a cmd to a device as part of error recovery.
461 * @scmd: SCSI Cmd to send.
462 * @timeout: Timeout for cmd.
465 * The initialization of the structures is quite a bit different in
466 * this case, and furthermore, there is a different completion handler
467 * vs scsi_dispatch_cmd.
469 * SUCCESS or FAILED or NEEDS_RETRY
471 static int scsi_send_eh_cmnd(struct scsi_cmnd
*scmd
, int timeout
)
473 struct scsi_device
*sdev
= scmd
->device
;
474 struct Scsi_Host
*shost
= sdev
->host
;
475 DECLARE_MUTEX_LOCKED(sem
);
480 * we will use a queued command if possible, otherwise we will
481 * emulate the queuing and calling of completion function ourselves.
483 if (sdev
->scsi_level
<= SCSI_2
)
484 scmd
->cmnd
[1] = (scmd
->cmnd
[1] & 0x1f) |
485 (sdev
->lun
<< 5 & 0xe0);
487 scsi_add_timer(scmd
, timeout
, scsi_eh_times_out
);
490 * set up the semaphore so we wait for the command to complete.
492 shost
->eh_action
= &sem
;
493 scmd
->request
->rq_status
= RQ_SCSI_BUSY
;
495 spin_lock_irqsave(shost
->host_lock
, flags
);
497 shost
->hostt
->queuecommand(scmd
, scsi_eh_done
);
498 spin_unlock_irqrestore(shost
->host_lock
, flags
);
501 scsi_log_completion(scmd
, SUCCESS
);
503 shost
->eh_action
= NULL
;
506 * see if timeout. if so, tell the host to forget about it.
507 * in other words, we don't want a callback any more.
509 if (scmd
->eh_eflags
& SCSI_EH_REC_TIMEOUT
) {
510 scmd
->eh_eflags
&= ~SCSI_EH_REC_TIMEOUT
;
513 * as far as the low level driver is
514 * concerned, this command is still active, so
515 * we must give the low level driver a chance
518 * FIXME(eric) - we are not tracking whether we could
519 * abort a timed out command or not. not sure how
520 * we should treat them differently anyways.
522 if (shost
->hostt
->eh_abort_handler
)
523 shost
->hostt
->eh_abort_handler(scmd
);
525 scmd
->request
->rq_status
= RQ_SCSI_DONE
;
529 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: scmd: %p, rtn:%x\n",
530 __FUNCTION__
, scmd
, rtn
));
533 * now examine the actual status codes to see whether the command
534 * actually did complete normally.
536 if (rtn
== SUCCESS
) {
537 rtn
= scsi_eh_completed_normally(scmd
);
538 SCSI_LOG_ERROR_RECOVERY(3,
539 printk("%s: scsi_eh_completed_normally %x\n",
556 * scsi_request_sense - Request sense data from a particular target.
557 * @scmd: SCSI cmd for request sense.
560 * Some hosts automatically obtain this information, others require
561 * that we obtain it on our own. This function will *not* return until
562 * the command either times out, or it completes.
564 static int scsi_request_sense(struct scsi_cmnd
*scmd
)
566 static unsigned char generic_sense
[6] =
567 {REQUEST_SENSE
, 0, 0, 0, 252, 0};
568 unsigned char *scsi_result
;
572 memcpy(scmd
->cmnd
, generic_sense
, sizeof(generic_sense
));
574 scsi_result
= kmalloc(252, GFP_ATOMIC
| ((scmd
->device
->host
->hostt
->unchecked_isa_dma
) ? __GFP_DMA
: 0));
577 if (unlikely(!scsi_result
)) {
578 printk(KERN_ERR
"%s: cannot allocate scsi_result.\n",
584 * zero the sense buffer. some host adapters automatically always
585 * request sense, so it is not a good idea that
586 * scmd->request_buffer and scmd->sense_buffer point to the same
587 * address (db). 0 is not a valid sense code.
589 memset(scmd
->sense_buffer
, 0, sizeof(scmd
->sense_buffer
));
590 memset(scsi_result
, 0, 252);
592 saved_result
= scmd
->result
;
593 scmd
->request_buffer
= scsi_result
;
594 scmd
->request_bufflen
= 252;
596 scmd
->cmd_len
= COMMAND_SIZE(scmd
->cmnd
[0]);
597 scmd
->sc_data_direction
= DMA_FROM_DEVICE
;
600 rtn
= scsi_send_eh_cmnd(scmd
, SENSE_TIMEOUT
);
602 /* last chance to have valid sense data */
603 if(!SCSI_SENSE_VALID(scmd
)) {
604 memcpy(scmd
->sense_buffer
, scmd
->request_buffer
,
605 sizeof(scmd
->sense_buffer
));
611 * when we eventually call scsi_finish, we really wish to complete
612 * the original request, so let's restore the original data. (db)
614 scsi_setup_cmd_retry(scmd
);
615 scmd
->result
= saved_result
;
620 * scsi_eh_finish_cmd - Handle a cmd that eh is finished with.
621 * @scmd: Original SCSI cmd that eh has finished.
622 * @done_q: Queue for processed commands.
625 * We don't want to use the normal command completion while we are are
626 * still handling errors - it may cause other commands to be queued,
627 * and that would disturb what we are doing. thus we really want to
628 * keep a list of pending commands for final completion, and once we
629 * are ready to leave error handling we handle completion for real.
631 static void scsi_eh_finish_cmd(struct scsi_cmnd
*scmd
,
632 struct list_head
*done_q
)
634 scmd
->device
->host
->host_failed
--;
638 * set this back so that the upper level can correctly free up
641 scsi_setup_cmd_retry(scmd
);
642 list_move_tail(&scmd
->eh_entry
, done_q
);
646 * scsi_eh_get_sense - Get device sense data.
647 * @work_q: Queue of commands to process.
648 * @done_q: Queue of proccessed commands..
651 * See if we need to request sense information. if so, then get it
652 * now, so we have a better idea of what to do.
655 * This has the unfortunate side effect that if a shost adapter does
656 * not automatically request sense information, that we end up shutting
657 * it down before we request it.
659 * All drivers should request sense information internally these days,
660 * so for now all I have to say is tough noogies if you end up in here.
662 * XXX: Long term this code should go away, but that needs an audit of
665 static int scsi_eh_get_sense(struct list_head
*work_q
,
666 struct list_head
*done_q
)
668 struct scsi_cmnd
*scmd
, *next
;
671 list_for_each_entry_safe(scmd
, next
, work_q
, eh_entry
) {
672 if ((scmd
->eh_eflags
& SCSI_EH_CANCEL_CMD
) ||
673 SCSI_SENSE_VALID(scmd
))
676 SCSI_LOG_ERROR_RECOVERY(2, scmd_printk(KERN_INFO
, scmd
,
677 "%s: requesting sense\n",
679 rtn
= scsi_request_sense(scmd
);
683 SCSI_LOG_ERROR_RECOVERY(3, printk("sense requested for %p"
684 " result %x\n", scmd
,
686 SCSI_LOG_ERROR_RECOVERY(3, scsi_print_sense("bh", scmd
));
688 rtn
= scsi_decide_disposition(scmd
);
691 * if the result was normal, then just pass it along to the
695 /* we don't want this command reissued, just
696 * finished with the sense data, so set
697 * retries to the max allowed to ensure it
698 * won't get reissued */
699 scmd
->retries
= scmd
->allowed
;
700 else if (rtn
!= NEEDS_RETRY
)
703 scsi_eh_finish_cmd(scmd
, done_q
);
706 return list_empty(work_q
);
710 * scsi_try_to_abort_cmd - Ask host to abort a running command.
711 * @scmd: SCSI cmd to abort from Lower Level.
714 * This function will not return until the user's completion function
715 * has been called. there is no timeout on this operation. if the
716 * author of the low-level driver wishes this operation to be timed,
717 * they can provide this facility themselves. helper functions in
718 * scsi_error.c can be supplied to make this easier to do.
720 static int scsi_try_to_abort_cmd(struct scsi_cmnd
*scmd
)
722 if (!scmd
->device
->host
->hostt
->eh_abort_handler
)
726 * scsi_done was called just after the command timed out and before
727 * we had a chance to process it. (db)
729 if (scmd
->serial_number
== 0)
731 return scmd
->device
->host
->hostt
->eh_abort_handler(scmd
);
735 * scsi_eh_tur - Send TUR to device.
736 * @scmd: Scsi cmd to send TUR
739 * 0 - Device is ready. 1 - Device NOT ready.
741 static int scsi_eh_tur(struct scsi_cmnd
*scmd
)
743 static unsigned char tur_command
[6] = {TEST_UNIT_READY
, 0, 0, 0, 0, 0};
744 int retry_cnt
= 1, rtn
;
748 memcpy(scmd
->cmnd
, tur_command
, sizeof(tur_command
));
751 * zero the sense buffer. the scsi spec mandates that any
752 * untransferred sense data should be interpreted as being zero.
754 memset(scmd
->sense_buffer
, 0, sizeof(scmd
->sense_buffer
));
756 saved_result
= scmd
->result
;
757 scmd
->request_buffer
= NULL
;
758 scmd
->request_bufflen
= 0;
760 scmd
->cmd_len
= COMMAND_SIZE(scmd
->cmnd
[0]);
762 scmd
->sc_data_direction
= DMA_NONE
;
764 rtn
= scsi_send_eh_cmnd(scmd
, SENSE_TIMEOUT
);
767 * when we eventually call scsi_finish, we really wish to complete
768 * the original request, so let's restore the original data. (db)
770 scsi_setup_cmd_retry(scmd
);
771 scmd
->result
= saved_result
;
774 * hey, we are done. let's look to see what happened.
776 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: scmd %p rtn %x\n",
777 __FUNCTION__
, scmd
, rtn
));
780 else if (rtn
== NEEDS_RETRY
) {
789 * scsi_eh_abort_cmds - abort canceled commands.
790 * @shost: scsi host being recovered.
791 * @eh_done_q: list_head for processed commands.
794 * Try and see whether or not it makes sense to try and abort the
795 * running command. this only works out to be the case if we have one
796 * command that has timed out. if the command simply failed, it makes
797 * no sense to try and abort the command, since as far as the shost
798 * adapter is concerned, it isn't running.
800 static int scsi_eh_abort_cmds(struct list_head
*work_q
,
801 struct list_head
*done_q
)
803 struct scsi_cmnd
*scmd
, *next
;
806 list_for_each_entry_safe(scmd
, next
, work_q
, eh_entry
) {
807 if (!(scmd
->eh_eflags
& SCSI_EH_CANCEL_CMD
))
809 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: aborting cmd:"
810 "0x%p\n", current
->comm
,
812 rtn
= scsi_try_to_abort_cmd(scmd
);
813 if (rtn
== SUCCESS
) {
814 scmd
->eh_eflags
&= ~SCSI_EH_CANCEL_CMD
;
815 if (!scsi_device_online(scmd
->device
) ||
816 !scsi_eh_tur(scmd
)) {
817 scsi_eh_finish_cmd(scmd
, done_q
);
821 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: aborting"
828 return list_empty(work_q
);
832 * scsi_try_bus_device_reset - Ask host to perform a BDR on a dev
833 * @scmd: SCSI cmd used to send BDR
836 * There is no timeout for this operation. if this operation is
837 * unreliable for a given host, then the host itself needs to put a
838 * timer on it, and set the host back to a consistent state prior to
841 static int scsi_try_bus_device_reset(struct scsi_cmnd
*scmd
)
845 if (!scmd
->device
->host
->hostt
->eh_device_reset_handler
)
848 rtn
= scmd
->device
->host
->hostt
->eh_device_reset_handler(scmd
);
849 if (rtn
== SUCCESS
) {
850 scmd
->device
->was_reset
= 1;
851 scmd
->device
->expecting_cc_ua
= 1;
858 * scsi_eh_try_stu - Send START_UNIT to device.
859 * @scmd: Scsi cmd to send START_UNIT
862 * 0 - Device is ready. 1 - Device NOT ready.
864 static int scsi_eh_try_stu(struct scsi_cmnd
*scmd
)
866 static unsigned char stu_command
[6] = {START_STOP
, 0, 0, 0, 1, 0};
870 if (!scmd
->device
->allow_restart
)
873 memcpy(scmd
->cmnd
, stu_command
, sizeof(stu_command
));
876 * zero the sense buffer. the scsi spec mandates that any
877 * untransferred sense data should be interpreted as being zero.
879 memset(scmd
->sense_buffer
, 0, sizeof(scmd
->sense_buffer
));
881 saved_result
= scmd
->result
;
882 scmd
->request_buffer
= NULL
;
883 scmd
->request_bufflen
= 0;
885 scmd
->cmd_len
= COMMAND_SIZE(scmd
->cmnd
[0]);
887 scmd
->sc_data_direction
= DMA_NONE
;
889 rtn
= scsi_send_eh_cmnd(scmd
, START_UNIT_TIMEOUT
);
892 * when we eventually call scsi_finish, we really wish to complete
893 * the original request, so let's restore the original data. (db)
895 scsi_setup_cmd_retry(scmd
);
896 scmd
->result
= saved_result
;
899 * hey, we are done. let's look to see what happened.
901 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: scmd %p rtn %x\n",
902 __FUNCTION__
, scmd
, rtn
));
909 * scsi_eh_stu - send START_UNIT if needed
910 * @shost: scsi host being recovered.
911 * @eh_done_q: list_head for processed commands.
914 * If commands are failing due to not ready, initializing command required,
915 * try revalidating the device, which will end up sending a start unit.
917 static int scsi_eh_stu(struct Scsi_Host
*shost
,
918 struct list_head
*work_q
,
919 struct list_head
*done_q
)
921 struct scsi_cmnd
*scmd
, *stu_scmd
, *next
;
922 struct scsi_device
*sdev
;
924 shost_for_each_device(sdev
, shost
) {
926 list_for_each_entry(scmd
, work_q
, eh_entry
)
927 if (scmd
->device
== sdev
&& SCSI_SENSE_VALID(scmd
) &&
928 scsi_check_sense(scmd
) == FAILED
) {
936 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending START_UNIT to sdev:"
937 " 0x%p\n", current
->comm
, sdev
));
939 if (!scsi_eh_try_stu(stu_scmd
)) {
940 if (!scsi_device_online(sdev
) ||
941 !scsi_eh_tur(stu_scmd
)) {
942 list_for_each_entry_safe(scmd
, next
,
944 if (scmd
->device
== sdev
)
945 scsi_eh_finish_cmd(scmd
, done_q
);
949 SCSI_LOG_ERROR_RECOVERY(3,
950 printk("%s: START_UNIT failed to sdev:"
951 " 0x%p\n", current
->comm
, sdev
));
955 return list_empty(work_q
);
960 * scsi_eh_bus_device_reset - send bdr if needed
961 * @shost: scsi host being recovered.
962 * @eh_done_q: list_head for processed commands.
965 * Try a bus device reset. still, look to see whether we have multiple
966 * devices that are jammed or not - if we have multiple devices, it
967 * makes no sense to try bus_device_reset - we really would need to try
968 * a bus_reset instead.
970 static int scsi_eh_bus_device_reset(struct Scsi_Host
*shost
,
971 struct list_head
*work_q
,
972 struct list_head
*done_q
)
974 struct scsi_cmnd
*scmd
, *bdr_scmd
, *next
;
975 struct scsi_device
*sdev
;
978 shost_for_each_device(sdev
, shost
) {
980 list_for_each_entry(scmd
, work_q
, eh_entry
)
981 if (scmd
->device
== sdev
) {
989 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending BDR sdev:"
990 " 0x%p\n", current
->comm
,
992 rtn
= scsi_try_bus_device_reset(bdr_scmd
);
993 if (rtn
== SUCCESS
) {
994 if (!scsi_device_online(sdev
) ||
995 !scsi_eh_tur(bdr_scmd
)) {
996 list_for_each_entry_safe(scmd
, next
,
998 if (scmd
->device
== sdev
)
999 scsi_eh_finish_cmd(scmd
,
1004 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: BDR"
1012 return list_empty(work_q
);
1016 * scsi_try_bus_reset - ask host to perform a bus reset
1017 * @scmd: SCSI cmd to send bus reset.
1019 static int scsi_try_bus_reset(struct scsi_cmnd
*scmd
)
1021 unsigned long flags
;
1024 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Snd Bus RST\n",
1027 if (!scmd
->device
->host
->hostt
->eh_bus_reset_handler
)
1030 rtn
= scmd
->device
->host
->hostt
->eh_bus_reset_handler(scmd
);
1032 if (rtn
== SUCCESS
) {
1033 if (!scmd
->device
->host
->hostt
->skip_settle_delay
)
1034 ssleep(BUS_RESET_SETTLE_TIME
);
1035 spin_lock_irqsave(scmd
->device
->host
->host_lock
, flags
);
1036 scsi_report_bus_reset(scmd
->device
->host
, scmd
->device
->channel
);
1037 spin_unlock_irqrestore(scmd
->device
->host
->host_lock
, flags
);
1044 * scsi_try_host_reset - ask host adapter to reset itself
1045 * @scmd: SCSI cmd to send hsot reset.
1047 static int scsi_try_host_reset(struct scsi_cmnd
*scmd
)
1049 unsigned long flags
;
1052 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Snd Host RST\n",
1055 if (!scmd
->device
->host
->hostt
->eh_host_reset_handler
)
1058 rtn
= scmd
->device
->host
->hostt
->eh_host_reset_handler(scmd
);
1060 if (rtn
== SUCCESS
) {
1061 if (!scmd
->device
->host
->hostt
->skip_settle_delay
)
1062 ssleep(HOST_RESET_SETTLE_TIME
);
1063 spin_lock_irqsave(scmd
->device
->host
->host_lock
, flags
);
1064 scsi_report_bus_reset(scmd
->device
->host
, scmd
->device
->channel
);
1065 spin_unlock_irqrestore(scmd
->device
->host
->host_lock
, flags
);
1072 * scsi_eh_bus_reset - send a bus reset
1073 * @shost: scsi host being recovered.
1074 * @eh_done_q: list_head for processed commands.
1076 static int scsi_eh_bus_reset(struct Scsi_Host
*shost
,
1077 struct list_head
*work_q
,
1078 struct list_head
*done_q
)
1080 struct scsi_cmnd
*scmd
, *chan_scmd
, *next
;
1081 unsigned int channel
;
1085 * we really want to loop over the various channels, and do this on
1086 * a channel by channel basis. we should also check to see if any
1087 * of the failed commands are on soft_reset devices, and if so, skip
1091 for (channel
= 0; channel
<= shost
->max_channel
; channel
++) {
1093 list_for_each_entry(scmd
, work_q
, eh_entry
) {
1094 if (channel
== scmd
->device
->channel
) {
1098 * FIXME add back in some support for
1099 * soft_reset devices.
1106 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending BRST chan:"
1107 " %d\n", current
->comm
,
1109 rtn
= scsi_try_bus_reset(chan_scmd
);
1110 if (rtn
== SUCCESS
) {
1111 list_for_each_entry_safe(scmd
, next
, work_q
, eh_entry
) {
1112 if (channel
== scmd
->device
->channel
)
1113 if (!scsi_device_online(scmd
->device
) ||
1115 scsi_eh_finish_cmd(scmd
,
1119 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: BRST"
1120 " failed chan: %d\n",
1125 return list_empty(work_q
);
1129 * scsi_eh_host_reset - send a host reset
1130 * @work_q: list_head for processed commands.
1131 * @done_q: list_head for processed commands.
1133 static int scsi_eh_host_reset(struct list_head
*work_q
,
1134 struct list_head
*done_q
)
1136 struct scsi_cmnd
*scmd
, *next
;
1139 if (!list_empty(work_q
)) {
1140 scmd
= list_entry(work_q
->next
,
1141 struct scsi_cmnd
, eh_entry
);
1143 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending HRST\n"
1146 rtn
= scsi_try_host_reset(scmd
);
1147 if (rtn
== SUCCESS
) {
1148 list_for_each_entry_safe(scmd
, next
, work_q
, eh_entry
) {
1149 if (!scsi_device_online(scmd
->device
) ||
1150 (!scsi_eh_try_stu(scmd
) && !scsi_eh_tur(scmd
)) ||
1152 scsi_eh_finish_cmd(scmd
, done_q
);
1155 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: HRST"
1160 return list_empty(work_q
);
1164 * scsi_eh_offline_sdevs - offline scsi devices that fail to recover
1165 * @work_q: list_head for processed commands.
1166 * @done_q: list_head for processed commands.
1169 static void scsi_eh_offline_sdevs(struct list_head
*work_q
,
1170 struct list_head
*done_q
)
1172 struct scsi_cmnd
*scmd
, *next
;
1174 list_for_each_entry_safe(scmd
, next
, work_q
, eh_entry
) {
1175 sdev_printk(KERN_INFO
, scmd
->device
,
1176 "scsi: Device offlined - not"
1177 " ready after error recovery\n");
1178 scsi_device_set_state(scmd
->device
, SDEV_OFFLINE
);
1179 if (scmd
->eh_eflags
& SCSI_EH_CANCEL_CMD
) {
1181 * FIXME: Handle lost cmds.
1184 scsi_eh_finish_cmd(scmd
, done_q
);
1190 * scsi_decide_disposition - Disposition a cmd on return from LLD.
1191 * @scmd: SCSI cmd to examine.
1194 * This is *only* called when we are examining the status after sending
1195 * out the actual data command. any commands that are queued for error
1196 * recovery (e.g. test_unit_ready) do *not* come through here.
1198 * When this routine returns failed, it means the error handler thread
1199 * is woken. In cases where the error code indicates an error that
1200 * doesn't require the error handler read (i.e. we don't need to
1201 * abort/reset), this function should return SUCCESS.
1203 int scsi_decide_disposition(struct scsi_cmnd
*scmd
)
1208 * if the device is offline, then we clearly just pass the result back
1209 * up to the top level.
1211 if (!scsi_device_online(scmd
->device
)) {
1212 SCSI_LOG_ERROR_RECOVERY(5, printk("%s: device offline - report"
1219 * first check the host byte, to see if there is anything in there
1220 * that would indicate what we need to do.
1222 switch (host_byte(scmd
->result
)) {
1223 case DID_PASSTHROUGH
:
1225 * no matter what, pass this through to the upper layer.
1226 * nuke this special code so that it looks like we are saying
1229 scmd
->result
&= 0xff00ffff;
1233 * looks good. drop through, and check the next byte.
1236 case DID_NO_CONNECT
:
1237 case DID_BAD_TARGET
:
1240 * note - this means that we just report the status back
1241 * to the top level driver, not that we actually think
1242 * that it indicates SUCCESS.
1246 * when the low level driver returns did_soft_error,
1247 * it is responsible for keeping an internal retry counter
1248 * in order to avoid endless loops (db)
1250 * actually this is a bug in this function here. we should
1251 * be mindful of the maximum number of retries specified
1252 * and not get stuck in a loop.
1254 case DID_SOFT_ERROR
:
1260 return ADD_TO_MLQUEUE
;
1263 if (msg_byte(scmd
->result
) == COMMAND_COMPLETE
&&
1264 status_byte(scmd
->result
) == RESERVATION_CONFLICT
)
1266 * execute reservation conflict processing code
1277 * when we scan the bus, we get timeout messages for
1278 * these commands if there is no device available.
1279 * other hosts report did_no_connect for the same thing.
1281 if ((scmd
->cmnd
[0] == TEST_UNIT_READY
||
1282 scmd
->cmnd
[0] == INQUIRY
)) {
1294 * next, check the message byte.
1296 if (msg_byte(scmd
->result
) != COMMAND_COMPLETE
)
1300 * check the status byte to see if this indicates anything special.
1302 switch (status_byte(scmd
->result
)) {
1305 * the case of trying to send too many commands to a
1306 * tagged queueing device.
1310 * device can't talk to us at the moment. Should only
1311 * occur (SAM-3) when the task queue is empty, so will cause
1312 * the empty queue handling to trigger a stall in the
1315 return ADD_TO_MLQUEUE
;
1317 case COMMAND_TERMINATED
:
1320 case CHECK_CONDITION
:
1321 rtn
= scsi_check_sense(scmd
);
1322 if (rtn
== NEEDS_RETRY
)
1324 /* if rtn == FAILED, we have no sense information;
1325 * returning FAILED will wake the error handler thread
1326 * to collect the sense and redo the decide
1329 case CONDITION_GOOD
:
1330 case INTERMEDIATE_GOOD
:
1331 case INTERMEDIATE_C_GOOD
:
1334 * who knows? FIXME(eric)
1338 case RESERVATION_CONFLICT
:
1339 sdev_printk(KERN_INFO
, scmd
->device
,
1340 "reservation conflict\n");
1341 return SUCCESS
; /* causes immediate i/o error */
1349 /* we requeue for retry because the error was retryable, and
1350 * the request was not marked fast fail. Note that above,
1351 * even if the request is marked fast fail, we still requeue
1352 * for queue congestion conditions (QUEUE_FULL or BUSY) */
1353 if ((++scmd
->retries
) < scmd
->allowed
1354 && !blk_noretry_request(scmd
->request
)) {
1358 * no more retries - report this one back to upper level.
1365 * scsi_eh_lock_done - done function for eh door lock request
1366 * @scmd: SCSI command block for the door lock request
1369 * We completed the asynchronous door lock request, and it has either
1370 * locked the door or failed. We must free the command structures
1371 * associated with this request.
1373 static void scsi_eh_lock_done(struct scsi_cmnd
*scmd
)
1375 struct scsi_request
*sreq
= scmd
->sc_request
;
1377 scsi_release_request(sreq
);
1382 * scsi_eh_lock_door - Prevent medium removal for the specified device
1383 * @sdev: SCSI device to prevent medium removal
1386 * We must be called from process context; scsi_allocate_request()
1390 * We queue up an asynchronous "ALLOW MEDIUM REMOVAL" request on the
1391 * head of the devices request queue, and continue.
1394 * scsi_allocate_request() may sleep waiting for existing requests to
1395 * be processed. However, since we haven't kicked off any request
1396 * processing for this host, this may deadlock.
1398 * If scsi_allocate_request() fails for what ever reason, we
1399 * completely forget to lock the door.
1401 static void scsi_eh_lock_door(struct scsi_device
*sdev
)
1403 struct scsi_request
*sreq
= scsi_allocate_request(sdev
, GFP_KERNEL
);
1405 if (unlikely(!sreq
)) {
1406 printk(KERN_ERR
"%s: request allocate failed,"
1407 "prevent media removal cmd not sent\n", __FUNCTION__
);
1411 sreq
->sr_cmnd
[0] = ALLOW_MEDIUM_REMOVAL
;
1412 sreq
->sr_cmnd
[1] = 0;
1413 sreq
->sr_cmnd
[2] = 0;
1414 sreq
->sr_cmnd
[3] = 0;
1415 sreq
->sr_cmnd
[4] = SCSI_REMOVAL_PREVENT
;
1416 sreq
->sr_cmnd
[5] = 0;
1417 sreq
->sr_data_direction
= DMA_NONE
;
1418 sreq
->sr_bufflen
= 0;
1419 sreq
->sr_buffer
= NULL
;
1420 sreq
->sr_allowed
= 5;
1421 sreq
->sr_done
= scsi_eh_lock_done
;
1422 sreq
->sr_timeout_per_command
= 10 * HZ
;
1423 sreq
->sr_cmd_len
= COMMAND_SIZE(sreq
->sr_cmnd
[0]);
1425 scsi_insert_special_req(sreq
, 1);
1430 * scsi_restart_operations - restart io operations to the specified host.
1431 * @shost: Host we are restarting.
1434 * When we entered the error handler, we blocked all further i/o to
1435 * this device. we need to 'reverse' this process.
1437 static void scsi_restart_operations(struct Scsi_Host
*shost
)
1439 struct scsi_device
*sdev
;
1440 unsigned long flags
;
1443 * If the door was locked, we need to insert a door lock request
1444 * onto the head of the SCSI request queue for the device. There
1445 * is no point trying to lock the door of an off-line device.
1447 shost_for_each_device(sdev
, shost
) {
1448 if (scsi_device_online(sdev
) && sdev
->locked
)
1449 scsi_eh_lock_door(sdev
);
1453 * next free up anything directly waiting upon the host. this
1454 * will be requests for character device operations, and also for
1455 * ioctls to queued block devices.
1457 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: waking up host to restart\n",
1460 spin_lock_irqsave(shost
->host_lock
, flags
);
1461 if (scsi_host_set_state(shost
, SHOST_RUNNING
))
1462 if (scsi_host_set_state(shost
, SHOST_CANCEL
))
1463 BUG_ON(scsi_host_set_state(shost
, SHOST_DEL
));
1464 spin_unlock_irqrestore(shost
->host_lock
, flags
);
1466 wake_up(&shost
->host_wait
);
1469 * finally we need to re-initiate requests that may be pending. we will
1470 * have had everything blocked while error handling is taking place, and
1471 * now that error recovery is done, we will need to ensure that these
1472 * requests are started.
1474 scsi_run_host_queues(shost
);
1478 * scsi_eh_ready_devs - check device ready state and recover if not.
1479 * @shost: host to be recovered.
1480 * @eh_done_q: list_head for processed commands.
1483 static void scsi_eh_ready_devs(struct Scsi_Host
*shost
,
1484 struct list_head
*work_q
,
1485 struct list_head
*done_q
)
1487 if (!scsi_eh_stu(shost
, work_q
, done_q
))
1488 if (!scsi_eh_bus_device_reset(shost
, work_q
, done_q
))
1489 if (!scsi_eh_bus_reset(shost
, work_q
, done_q
))
1490 if (!scsi_eh_host_reset(work_q
, done_q
))
1491 scsi_eh_offline_sdevs(work_q
, done_q
);
1495 * scsi_eh_flush_done_q - finish processed commands or retry them.
1496 * @done_q: list_head of processed commands.
1499 static void scsi_eh_flush_done_q(struct list_head
*done_q
)
1501 struct scsi_cmnd
*scmd
, *next
;
1503 list_for_each_entry_safe(scmd
, next
, done_q
, eh_entry
) {
1504 list_del_init(&scmd
->eh_entry
);
1505 if (scsi_device_online(scmd
->device
) &&
1506 !blk_noretry_request(scmd
->request
) &&
1507 (++scmd
->retries
< scmd
->allowed
)) {
1508 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: flush"
1512 scsi_queue_insert(scmd
, SCSI_MLQUEUE_EH_RETRY
);
1515 * If just we got sense for the device (called
1516 * scsi_eh_get_sense), scmd->result is already
1517 * set, do not set DRIVER_TIMEOUT.
1520 scmd
->result
|= (DRIVER_TIMEOUT
<< 24);
1521 SCSI_LOG_ERROR_RECOVERY(3, printk("%s: flush finish"
1523 current
->comm
, scmd
));
1524 scsi_finish_command(scmd
);
1530 * scsi_unjam_host - Attempt to fix a host which has a cmd that failed.
1531 * @shost: Host to unjam.
1534 * When we come in here, we *know* that all commands on the bus have
1535 * either completed, failed or timed out. we also know that no further
1536 * commands are being sent to the host, so things are relatively quiet
1537 * and we have freedom to fiddle with things as we wish.
1539 * This is only the *default* implementation. it is possible for
1540 * individual drivers to supply their own version of this function, and
1541 * if the maintainer wishes to do this, it is strongly suggested that
1542 * this function be taken as a template and modified. this function
1543 * was designed to correctly handle problems for about 95% of the
1544 * different cases out there, and it should always provide at least a
1545 * reasonable amount of error recovery.
1547 * Any command marked 'failed' or 'timeout' must eventually have
1548 * scsi_finish_cmd() called for it. we do all of the retry stuff
1549 * here, so when we restart the host after we return it should have an
1552 static void scsi_unjam_host(struct Scsi_Host
*shost
)
1554 unsigned long flags
;
1555 LIST_HEAD(eh_work_q
);
1556 LIST_HEAD(eh_done_q
);
1558 spin_lock_irqsave(shost
->host_lock
, flags
);
1559 list_splice_init(&shost
->eh_cmd_q
, &eh_work_q
);
1560 spin_unlock_irqrestore(shost
->host_lock
, flags
);
1562 SCSI_LOG_ERROR_RECOVERY(1, scsi_eh_prt_fail_stats(shost
, &eh_work_q
));
1564 if (!scsi_eh_get_sense(&eh_work_q
, &eh_done_q
))
1565 if (!scsi_eh_abort_cmds(&eh_work_q
, &eh_done_q
))
1566 scsi_eh_ready_devs(shost
, &eh_work_q
, &eh_done_q
);
1568 scsi_eh_flush_done_q(&eh_done_q
);
1572 * scsi_error_handler - Handle errors/timeouts of SCSI cmds.
1573 * @data: Host for which we are running.
1576 * This is always run in the context of a kernel thread. The idea is
1577 * that we start this thing up when the kernel starts up (one per host
1578 * that we detect), and it immediately goes to sleep and waits for some
1579 * event (i.e. failure). When this takes place, we have the job of
1580 * trying to unjam the bus and restarting things.
1582 int scsi_error_handler(void *data
)
1584 struct Scsi_Host
*shost
= (struct Scsi_Host
*) data
;
1587 current
->flags
|= PF_NOFREEZE
;
1591 * Note - we always use TASK_INTERRUPTIBLE even if the module
1592 * was loaded as part of the kernel. The reason is that
1593 * UNINTERRUPTIBLE would cause this thread to be counted in
1594 * the load average as a running process, and an interruptible
1597 set_current_state(TASK_INTERRUPTIBLE
);
1598 while (!kthread_should_stop()) {
1599 if (shost
->host_failed
== 0 ||
1600 shost
->host_failed
!= shost
->host_busy
) {
1601 SCSI_LOG_ERROR_RECOVERY(1, printk("Error handler"
1606 set_current_state(TASK_INTERRUPTIBLE
);
1610 __set_current_state(TASK_RUNNING
);
1611 SCSI_LOG_ERROR_RECOVERY(1, printk("Error handler"
1612 " scsi_eh_%d waking"
1613 " up\n",shost
->host_no
));
1615 shost
->eh_active
= 1;
1618 * We have a host that is failing for some reason. Figure out
1619 * what we need to do to get it up and online again (if we can).
1620 * If we fail, we end up taking the thing offline.
1622 if (shost
->hostt
->eh_strategy_handler
)
1623 rtn
= shost
->hostt
->eh_strategy_handler(shost
);
1625 scsi_unjam_host(shost
);
1627 shost
->eh_active
= 0;
1630 * Note - if the above fails completely, the action is to take
1631 * individual devices offline and flush the queue of any
1632 * outstanding requests that may have been pending. When we
1633 * restart, we restart any I/O to any other devices on the bus
1634 * which are still online.
1636 scsi_restart_operations(shost
);
1637 set_current_state(TASK_INTERRUPTIBLE
);
1640 __set_current_state(TASK_RUNNING
);
1642 SCSI_LOG_ERROR_RECOVERY(1, printk("Error handler scsi_eh_%d"
1643 " exiting\n",shost
->host_no
));
1646 * Make sure that nobody tries to wake us up again.
1648 shost
->ehandler
= NULL
;
1653 * Function: scsi_report_bus_reset()
1655 * Purpose: Utility function used by low-level drivers to report that
1656 * they have observed a bus reset on the bus being handled.
1658 * Arguments: shost - Host in question
1659 * channel - channel on which reset was observed.
1663 * Lock status: Host lock must be held.
1665 * Notes: This only needs to be called if the reset is one which
1666 * originates from an unknown location. Resets originated
1667 * by the mid-level itself don't need to call this, but there
1668 * should be no harm.
1670 * The main purpose of this is to make sure that a CHECK_CONDITION
1671 * is properly treated.
1673 void scsi_report_bus_reset(struct Scsi_Host
*shost
, int channel
)
1675 struct scsi_device
*sdev
;
1677 __shost_for_each_device(sdev
, shost
) {
1678 if (channel
== sdev
->channel
) {
1679 sdev
->was_reset
= 1;
1680 sdev
->expecting_cc_ua
= 1;
1684 EXPORT_SYMBOL(scsi_report_bus_reset
);
1687 * Function: scsi_report_device_reset()
1689 * Purpose: Utility function used by low-level drivers to report that
1690 * they have observed a device reset on the device being handled.
1692 * Arguments: shost - Host in question
1693 * channel - channel on which reset was observed
1694 * target - target on which reset was observed
1698 * Lock status: Host lock must be held
1700 * Notes: This only needs to be called if the reset is one which
1701 * originates from an unknown location. Resets originated
1702 * by the mid-level itself don't need to call this, but there
1703 * should be no harm.
1705 * The main purpose of this is to make sure that a CHECK_CONDITION
1706 * is properly treated.
1708 void scsi_report_device_reset(struct Scsi_Host
*shost
, int channel
, int target
)
1710 struct scsi_device
*sdev
;
1712 __shost_for_each_device(sdev
, shost
) {
1713 if (channel
== sdev
->channel
&&
1714 target
== sdev
->id
) {
1715 sdev
->was_reset
= 1;
1716 sdev
->expecting_cc_ua
= 1;
1720 EXPORT_SYMBOL(scsi_report_device_reset
);
1723 scsi_reset_provider_done_command(struct scsi_cmnd
*scmd
)
1728 * Function: scsi_reset_provider
1730 * Purpose: Send requested reset to a bus or device at any phase.
1732 * Arguments: device - device to send reset to
1733 * flag - reset type (see scsi.h)
1735 * Returns: SUCCESS/FAILURE.
1737 * Notes: This is used by the SCSI Generic driver to provide
1738 * Bus/Device reset capability.
1741 scsi_reset_provider(struct scsi_device
*dev
, int flag
)
1743 struct scsi_cmnd
*scmd
= scsi_get_command(dev
, GFP_KERNEL
);
1747 scmd
->request
= &req
;
1748 memset(&scmd
->eh_timeout
, 0, sizeof(scmd
->eh_timeout
));
1749 scmd
->request
->rq_status
= RQ_SCSI_BUSY
;
1751 memset(&scmd
->cmnd
, '\0', sizeof(scmd
->cmnd
));
1753 scmd
->scsi_done
= scsi_reset_provider_done_command
;
1755 scmd
->buffer
= NULL
;
1757 scmd
->request_buffer
= NULL
;
1758 scmd
->request_bufflen
= 0;
1762 scmd
->sc_data_direction
= DMA_BIDIRECTIONAL
;
1763 scmd
->sc_request
= NULL
;
1764 scmd
->sc_magic
= SCSI_CMND_MAGIC
;
1766 init_timer(&scmd
->eh_timeout
);
1769 * Sometimes the command can get back into the timer chain,
1770 * so use the pid as an identifier.
1775 case SCSI_TRY_RESET_DEVICE
:
1776 rtn
= scsi_try_bus_device_reset(scmd
);
1780 case SCSI_TRY_RESET_BUS
:
1781 rtn
= scsi_try_bus_reset(scmd
);
1785 case SCSI_TRY_RESET_HOST
:
1786 rtn
= scsi_try_host_reset(scmd
);
1792 scsi_next_command(scmd
);
1795 EXPORT_SYMBOL(scsi_reset_provider
);
1798 * scsi_normalize_sense - normalize main elements from either fixed or
1799 * descriptor sense data format into a common format.
1801 * @sense_buffer: byte array containing sense data returned by device
1802 * @sb_len: number of valid bytes in sense_buffer
1803 * @sshdr: pointer to instance of structure that common
1804 * elements are written to.
1807 * The "main elements" from sense data are: response_code, sense_key,
1808 * asc, ascq and additional_length (only for descriptor format).
1810 * Typically this function can be called after a device has
1811 * responded to a SCSI command with the CHECK_CONDITION status.
1814 * 1 if valid sense data information found, else 0;
1816 int scsi_normalize_sense(const u8
*sense_buffer
, int sb_len
,
1817 struct scsi_sense_hdr
*sshdr
)
1819 if (!sense_buffer
|| !sb_len
)
1822 memset(sshdr
, 0, sizeof(struct scsi_sense_hdr
));
1824 sshdr
->response_code
= (sense_buffer
[0] & 0x7f);
1826 if (!scsi_sense_valid(sshdr
))
1829 if (sshdr
->response_code
>= 0x72) {
1834 sshdr
->sense_key
= (sense_buffer
[1] & 0xf);
1836 sshdr
->asc
= sense_buffer
[2];
1838 sshdr
->ascq
= sense_buffer
[3];
1840 sshdr
->additional_length
= sense_buffer
[7];
1846 sshdr
->sense_key
= (sense_buffer
[2] & 0xf);
1848 sb_len
= (sb_len
< (sense_buffer
[7] + 8)) ?
1849 sb_len
: (sense_buffer
[7] + 8);
1851 sshdr
->asc
= sense_buffer
[12];
1853 sshdr
->ascq
= sense_buffer
[13];
1859 EXPORT_SYMBOL(scsi_normalize_sense
);
1861 int scsi_request_normalize_sense(struct scsi_request
*sreq
,
1862 struct scsi_sense_hdr
*sshdr
)
1864 return scsi_normalize_sense(sreq
->sr_sense_buffer
,
1865 sizeof(sreq
->sr_sense_buffer
), sshdr
);
1867 EXPORT_SYMBOL(scsi_request_normalize_sense
);
1869 int scsi_command_normalize_sense(struct scsi_cmnd
*cmd
,
1870 struct scsi_sense_hdr
*sshdr
)
1872 return scsi_normalize_sense(cmd
->sense_buffer
,
1873 sizeof(cmd
->sense_buffer
), sshdr
);
1875 EXPORT_SYMBOL(scsi_command_normalize_sense
);
1878 * scsi_sense_desc_find - search for a given descriptor type in
1879 * descriptor sense data format.
1881 * @sense_buffer: byte array of descriptor format sense data
1882 * @sb_len: number of valid bytes in sense_buffer
1883 * @desc_type: value of descriptor type to find
1884 * (e.g. 0 -> information)
1887 * only valid when sense data is in descriptor format
1890 * pointer to start of (first) descriptor if found else NULL
1892 const u8
* scsi_sense_desc_find(const u8
* sense_buffer
, int sb_len
,
1895 int add_sen_len
, add_len
, desc_len
, k
;
1898 if ((sb_len
< 8) || (0 == (add_sen_len
= sense_buffer
[7])))
1900 if ((sense_buffer
[0] < 0x72) || (sense_buffer
[0] > 0x73))
1902 add_sen_len
= (add_sen_len
< (sb_len
- 8)) ?
1903 add_sen_len
: (sb_len
- 8);
1904 descp
= &sense_buffer
[8];
1905 for (desc_len
= 0, k
= 0; k
< add_sen_len
; k
+= desc_len
) {
1907 add_len
= (k
< (add_sen_len
- 1)) ? descp
[1]: -1;
1908 desc_len
= add_len
+ 2;
1909 if (descp
[0] == desc_type
)
1911 if (add_len
< 0) // short descriptor ??
1916 EXPORT_SYMBOL(scsi_sense_desc_find
);
1919 * scsi_get_sense_info_fld - attempts to get information field from
1920 * sense data (either fixed or descriptor format)
1922 * @sense_buffer: byte array of sense data
1923 * @sb_len: number of valid bytes in sense_buffer
1924 * @info_out: pointer to 64 integer where 8 or 4 byte information
1925 * field will be placed if found.
1928 * 1 if information field found, 0 if not found.
1930 int scsi_get_sense_info_fld(const u8
* sense_buffer
, int sb_len
,
1939 switch (sense_buffer
[0] & 0x7f) {
1942 if (sense_buffer
[0] & 0x80) {
1943 *info_out
= (sense_buffer
[3] << 24) +
1944 (sense_buffer
[4] << 16) +
1945 (sense_buffer
[5] << 8) + sense_buffer
[6];
1951 ucp
= scsi_sense_desc_find(sense_buffer
, sb_len
,
1953 if (ucp
&& (0xa == ucp
[1])) {
1955 for (j
= 0; j
< 8; ++j
) {
1968 EXPORT_SYMBOL(scsi_get_sense_info_fld
);