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1da177e4 LT |
1 | /* |
2 | * scsi_error.c Copyright (C) 1997 Eric Youngdale | |
3 | * | |
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. | |
8 | * | |
9 | * Restructured scsi_unjam_host and associated functions. | |
10 | * September 04, 2002 Mike Anderson (andmike@us.ibm.com) | |
11 | * | |
12 | * Forward port of Russell King's (rmk@arm.linux.org.uk) changes and | |
13 | * minor cleanups. | |
14 | * September 30, 2002 Mike Anderson (andmike@us.ibm.com) | |
15 | */ | |
16 | ||
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> | |
c5478def | 23 | #include <linux/kthread.h> |
1da177e4 LT |
24 | #include <linux/interrupt.h> |
25 | #include <linux/blkdev.h> | |
26 | #include <linux/delay.h> | |
27 | ||
28 | #include <scsi/scsi.h> | |
beb40487 | 29 | #include <scsi/scsi_cmnd.h> |
1da177e4 LT |
30 | #include <scsi/scsi_dbg.h> |
31 | #include <scsi/scsi_device.h> | |
32 | #include <scsi/scsi_eh.h> | |
c829c394 | 33 | #include <scsi/scsi_transport.h> |
1da177e4 LT |
34 | #include <scsi/scsi_host.h> |
35 | #include <scsi/scsi_ioctl.h> | |
1da177e4 LT |
36 | |
37 | #include "scsi_priv.h" | |
38 | #include "scsi_logging.h" | |
39 | ||
40 | #define SENSE_TIMEOUT (10*HZ) | |
41 | #define START_UNIT_TIMEOUT (30*HZ) | |
42 | ||
43 | /* | |
44 | * These should *probably* be handled by the host itself. | |
45 | * Since it is allowed to sleep, it probably should. | |
46 | */ | |
47 | #define BUS_RESET_SETTLE_TIME (10) | |
48 | #define HOST_RESET_SETTLE_TIME (10) | |
49 | ||
50 | /* called with shost->host_lock held */ | |
51 | void scsi_eh_wakeup(struct Scsi_Host *shost) | |
52 | { | |
53 | if (shost->host_busy == shost->host_failed) { | |
3ed7a470 | 54 | wake_up_process(shost->ehandler); |
1da177e4 LT |
55 | SCSI_LOG_ERROR_RECOVERY(5, |
56 | printk("Waking error handler thread\n")); | |
57 | } | |
58 | } | |
f8bbfc24 TH |
59 | |
60 | /** | |
61 | * scsi_schedule_eh - schedule EH for SCSI host | |
62 | * @shost: SCSI host to invoke error handling on. | |
63 | * | |
64 | * Schedule SCSI EH without scmd. | |
65 | **/ | |
66 | void scsi_schedule_eh(struct Scsi_Host *shost) | |
67 | { | |
68 | unsigned long flags; | |
69 | ||
70 | spin_lock_irqsave(shost->host_lock, flags); | |
71 | ||
72 | if (scsi_host_set_state(shost, SHOST_RECOVERY) == 0 || | |
73 | scsi_host_set_state(shost, SHOST_CANCEL_RECOVERY) == 0) { | |
74 | shost->host_eh_scheduled++; | |
75 | scsi_eh_wakeup(shost); | |
76 | } | |
77 | ||
78 | spin_unlock_irqrestore(shost->host_lock, flags); | |
79 | } | |
80 | EXPORT_SYMBOL_GPL(scsi_schedule_eh); | |
1da177e4 LT |
81 | |
82 | /** | |
83 | * scsi_eh_scmd_add - add scsi cmd to error handling. | |
84 | * @scmd: scmd to run eh on. | |
85 | * @eh_flag: optional SCSI_EH flag. | |
86 | * | |
87 | * Return value: | |
88 | * 0 on failure. | |
89 | **/ | |
90 | int scsi_eh_scmd_add(struct scsi_cmnd *scmd, int eh_flag) | |
91 | { | |
92 | struct Scsi_Host *shost = scmd->device->host; | |
93 | unsigned long flags; | |
939647ee | 94 | int ret = 0; |
1da177e4 | 95 | |
3ed7a470 | 96 | if (!shost->ehandler) |
1da177e4 LT |
97 | return 0; |
98 | ||
99 | spin_lock_irqsave(shost->host_lock, flags); | |
939647ee JB |
100 | if (scsi_host_set_state(shost, SHOST_RECOVERY)) |
101 | if (scsi_host_set_state(shost, SHOST_CANCEL_RECOVERY)) | |
102 | goto out_unlock; | |
1da177e4 | 103 | |
939647ee | 104 | ret = 1; |
3111b0d1 | 105 | scmd->eh_eflags |= eh_flag; |
1da177e4 | 106 | list_add_tail(&scmd->eh_entry, &shost->eh_cmd_q); |
1da177e4 LT |
107 | shost->host_failed++; |
108 | scsi_eh_wakeup(shost); | |
939647ee | 109 | out_unlock: |
1da177e4 | 110 | spin_unlock_irqrestore(shost->host_lock, flags); |
939647ee | 111 | return ret; |
1da177e4 LT |
112 | } |
113 | ||
114 | /** | |
115 | * scsi_add_timer - Start timeout timer for a single scsi command. | |
116 | * @scmd: scsi command that is about to start running. | |
117 | * @timeout: amount of time to allow this command to run. | |
118 | * @complete: timeout function to call if timer isn't canceled. | |
119 | * | |
120 | * Notes: | |
121 | * This should be turned into an inline function. Each scsi command | |
122 | * has its own timer, and as it is added to the queue, we set up the | |
123 | * timer. When the command completes, we cancel the timer. | |
124 | **/ | |
125 | void scsi_add_timer(struct scsi_cmnd *scmd, int timeout, | |
126 | void (*complete)(struct scsi_cmnd *)) | |
127 | { | |
128 | ||
129 | /* | |
130 | * If the clock was already running for this command, then | |
131 | * first delete the timer. The timer handling code gets rather | |
132 | * confused if we don't do this. | |
133 | */ | |
134 | if (scmd->eh_timeout.function) | |
135 | del_timer(&scmd->eh_timeout); | |
136 | ||
137 | scmd->eh_timeout.data = (unsigned long)scmd; | |
138 | scmd->eh_timeout.expires = jiffies + timeout; | |
139 | scmd->eh_timeout.function = (void (*)(unsigned long)) complete; | |
140 | ||
141 | SCSI_LOG_ERROR_RECOVERY(5, printk("%s: scmd: %p, time:" | |
142 | " %d, (%p)\n", __FUNCTION__, | |
143 | scmd, timeout, complete)); | |
144 | ||
145 | add_timer(&scmd->eh_timeout); | |
146 | } | |
1da177e4 LT |
147 | |
148 | /** | |
149 | * scsi_delete_timer - Delete/cancel timer for a given function. | |
150 | * @scmd: Cmd that we are canceling timer for | |
151 | * | |
152 | * Notes: | |
153 | * This should be turned into an inline function. | |
154 | * | |
155 | * Return value: | |
156 | * 1 if we were able to detach the timer. 0 if we blew it, and the | |
157 | * timer function has already started to run. | |
158 | **/ | |
159 | int scsi_delete_timer(struct scsi_cmnd *scmd) | |
160 | { | |
161 | int rtn; | |
162 | ||
163 | rtn = del_timer(&scmd->eh_timeout); | |
164 | ||
165 | SCSI_LOG_ERROR_RECOVERY(5, printk("%s: scmd: %p," | |
166 | " rtn: %d\n", __FUNCTION__, | |
167 | scmd, rtn)); | |
168 | ||
169 | scmd->eh_timeout.data = (unsigned long)NULL; | |
170 | scmd->eh_timeout.function = NULL; | |
171 | ||
172 | return rtn; | |
173 | } | |
1da177e4 LT |
174 | |
175 | /** | |
176 | * scsi_times_out - Timeout function for normal scsi commands. | |
177 | * @scmd: Cmd that is timing out. | |
178 | * | |
179 | * Notes: | |
180 | * We do not need to lock this. There is the potential for a race | |
181 | * only in that the normal completion handling might run, but if the | |
182 | * normal completion function determines that the timer has already | |
183 | * fired, then it mustn't do anything. | |
184 | **/ | |
185 | void scsi_times_out(struct scsi_cmnd *scmd) | |
186 | { | |
187 | scsi_log_completion(scmd, TIMEOUT_ERROR); | |
188 | ||
c829c394 JS |
189 | if (scmd->device->host->transportt->eh_timed_out) |
190 | switch (scmd->device->host->transportt->eh_timed_out(scmd)) { | |
1da177e4 LT |
191 | case EH_HANDLED: |
192 | __scsi_done(scmd); | |
193 | return; | |
194 | case EH_RESET_TIMER: | |
1da177e4 LT |
195 | scsi_add_timer(scmd, scmd->timeout_per_command, |
196 | scsi_times_out); | |
197 | return; | |
198 | case EH_NOT_HANDLED: | |
199 | break; | |
200 | } | |
201 | ||
202 | if (unlikely(!scsi_eh_scmd_add(scmd, SCSI_EH_CANCEL_CMD))) { | |
939647ee JB |
203 | scmd->result |= DID_TIME_OUT << 16; |
204 | __scsi_done(scmd); | |
1da177e4 LT |
205 | } |
206 | } | |
207 | ||
208 | /** | |
209 | * scsi_block_when_processing_errors - Prevent cmds from being queued. | |
210 | * @sdev: Device on which we are performing recovery. | |
211 | * | |
212 | * Description: | |
213 | * We block until the host is out of error recovery, and then check to | |
214 | * see whether the host or the device is offline. | |
215 | * | |
216 | * Return value: | |
217 | * 0 when dev was taken offline by error recovery. 1 OK to proceed. | |
218 | **/ | |
219 | int scsi_block_when_processing_errors(struct scsi_device *sdev) | |
220 | { | |
221 | int online; | |
222 | ||
939647ee | 223 | wait_event(sdev->host->host_wait, !scsi_host_in_recovery(sdev->host)); |
1da177e4 LT |
224 | |
225 | online = scsi_device_online(sdev); | |
226 | ||
227 | SCSI_LOG_ERROR_RECOVERY(5, printk("%s: rtn: %d\n", __FUNCTION__, | |
228 | online)); | |
229 | ||
230 | return online; | |
231 | } | |
232 | EXPORT_SYMBOL(scsi_block_when_processing_errors); | |
233 | ||
234 | #ifdef CONFIG_SCSI_LOGGING | |
235 | /** | |
236 | * scsi_eh_prt_fail_stats - Log info on failures. | |
237 | * @shost: scsi host being recovered. | |
238 | * @work_q: Queue of scsi cmds to process. | |
239 | **/ | |
240 | static inline void scsi_eh_prt_fail_stats(struct Scsi_Host *shost, | |
241 | struct list_head *work_q) | |
242 | { | |
243 | struct scsi_cmnd *scmd; | |
244 | struct scsi_device *sdev; | |
245 | int total_failures = 0; | |
246 | int cmd_failed = 0; | |
247 | int cmd_cancel = 0; | |
248 | int devices_failed = 0; | |
249 | ||
250 | shost_for_each_device(sdev, shost) { | |
251 | list_for_each_entry(scmd, work_q, eh_entry) { | |
252 | if (scmd->device == sdev) { | |
253 | ++total_failures; | |
3111b0d1 | 254 | if (scmd->eh_eflags & SCSI_EH_CANCEL_CMD) |
1da177e4 LT |
255 | ++cmd_cancel; |
256 | else | |
257 | ++cmd_failed; | |
258 | } | |
259 | } | |
260 | ||
261 | if (cmd_cancel || cmd_failed) { | |
262 | SCSI_LOG_ERROR_RECOVERY(3, | |
9ccfc756 JB |
263 | sdev_printk(KERN_INFO, sdev, |
264 | "%s: cmds failed: %d, cancel: %d\n", | |
265 | __FUNCTION__, cmd_failed, | |
266 | cmd_cancel)); | |
1da177e4 LT |
267 | cmd_cancel = 0; |
268 | cmd_failed = 0; | |
269 | ++devices_failed; | |
270 | } | |
271 | } | |
272 | ||
273 | SCSI_LOG_ERROR_RECOVERY(2, printk("Total of %d commands on %d" | |
274 | " devices require eh work\n", | |
275 | total_failures, devices_failed)); | |
276 | } | |
277 | #endif | |
278 | ||
279 | /** | |
280 | * scsi_check_sense - Examine scsi cmd sense | |
281 | * @scmd: Cmd to have sense checked. | |
282 | * | |
283 | * Return value: | |
284 | * SUCCESS or FAILED or NEEDS_RETRY | |
285 | * | |
286 | * Notes: | |
287 | * When a deferred error is detected the current command has | |
288 | * not been executed and needs retrying. | |
289 | **/ | |
290 | static int scsi_check_sense(struct scsi_cmnd *scmd) | |
291 | { | |
292 | struct scsi_sense_hdr sshdr; | |
293 | ||
294 | if (! scsi_command_normalize_sense(scmd, &sshdr)) | |
295 | return FAILED; /* no valid sense data */ | |
296 | ||
297 | if (scsi_sense_is_deferred(&sshdr)) | |
298 | return NEEDS_RETRY; | |
299 | ||
300 | /* | |
301 | * Previous logic looked for FILEMARK, EOM or ILI which are | |
302 | * mainly associated with tapes and returned SUCCESS. | |
303 | */ | |
304 | if (sshdr.response_code == 0x70) { | |
305 | /* fixed format */ | |
306 | if (scmd->sense_buffer[2] & 0xe0) | |
307 | return SUCCESS; | |
308 | } else { | |
309 | /* | |
310 | * descriptor format: look for "stream commands sense data | |
311 | * descriptor" (see SSC-3). Assume single sense data | |
312 | * descriptor. Ignore ILI from SBC-2 READ LONG and WRITE LONG. | |
313 | */ | |
314 | if ((sshdr.additional_length > 3) && | |
315 | (scmd->sense_buffer[8] == 0x4) && | |
316 | (scmd->sense_buffer[11] & 0xe0)) | |
317 | return SUCCESS; | |
318 | } | |
319 | ||
320 | switch (sshdr.sense_key) { | |
321 | case NO_SENSE: | |
322 | return SUCCESS; | |
323 | case RECOVERED_ERROR: | |
324 | return /* soft_error */ SUCCESS; | |
325 | ||
326 | case ABORTED_COMMAND: | |
327 | return NEEDS_RETRY; | |
328 | case NOT_READY: | |
329 | case UNIT_ATTENTION: | |
330 | /* | |
331 | * if we are expecting a cc/ua because of a bus reset that we | |
332 | * performed, treat this just as a retry. otherwise this is | |
333 | * information that we should pass up to the upper-level driver | |
334 | * so that we can deal with it there. | |
335 | */ | |
336 | if (scmd->device->expecting_cc_ua) { | |
337 | scmd->device->expecting_cc_ua = 0; | |
338 | return NEEDS_RETRY; | |
339 | } | |
340 | /* | |
341 | * if the device is in the process of becoming ready, we | |
342 | * should retry. | |
343 | */ | |
344 | if ((sshdr.asc == 0x04) && (sshdr.ascq == 0x01)) | |
345 | return NEEDS_RETRY; | |
346 | /* | |
347 | * if the device is not started, we need to wake | |
348 | * the error handler to start the motor | |
349 | */ | |
350 | if (scmd->device->allow_restart && | |
351 | (sshdr.asc == 0x04) && (sshdr.ascq == 0x02)) | |
352 | return FAILED; | |
353 | return SUCCESS; | |
354 | ||
355 | /* these three are not supported */ | |
356 | case COPY_ABORTED: | |
357 | case VOLUME_OVERFLOW: | |
358 | case MISCOMPARE: | |
359 | return SUCCESS; | |
360 | ||
361 | case MEDIUM_ERROR: | |
362 | return NEEDS_RETRY; | |
363 | ||
364 | case HARDWARE_ERROR: | |
365 | if (scmd->device->retry_hwerror) | |
366 | return NEEDS_RETRY; | |
367 | else | |
368 | return SUCCESS; | |
369 | ||
370 | case ILLEGAL_REQUEST: | |
371 | case BLANK_CHECK: | |
372 | case DATA_PROTECT: | |
373 | default: | |
374 | return SUCCESS; | |
375 | } | |
376 | } | |
377 | ||
378 | /** | |
379 | * scsi_eh_completed_normally - Disposition a eh cmd on return from LLD. | |
380 | * @scmd: SCSI cmd to examine. | |
381 | * | |
382 | * Notes: | |
383 | * This is *only* called when we are examining the status of commands | |
384 | * queued during error recovery. the main difference here is that we | |
385 | * don't allow for the possibility of retries here, and we are a lot | |
386 | * more restrictive about what we consider acceptable. | |
387 | **/ | |
388 | static int scsi_eh_completed_normally(struct scsi_cmnd *scmd) | |
389 | { | |
390 | /* | |
391 | * first check the host byte, to see if there is anything in there | |
392 | * that would indicate what we need to do. | |
393 | */ | |
394 | if (host_byte(scmd->result) == DID_RESET) { | |
395 | /* | |
396 | * rats. we are already in the error handler, so we now | |
397 | * get to try and figure out what to do next. if the sense | |
398 | * is valid, we have a pretty good idea of what to do. | |
399 | * if not, we mark it as FAILED. | |
400 | */ | |
401 | return scsi_check_sense(scmd); | |
402 | } | |
403 | if (host_byte(scmd->result) != DID_OK) | |
404 | return FAILED; | |
405 | ||
406 | /* | |
407 | * next, check the message byte. | |
408 | */ | |
409 | if (msg_byte(scmd->result) != COMMAND_COMPLETE) | |
410 | return FAILED; | |
411 | ||
412 | /* | |
413 | * now, check the status byte to see if this indicates | |
414 | * anything special. | |
415 | */ | |
416 | switch (status_byte(scmd->result)) { | |
417 | case GOOD: | |
418 | case COMMAND_TERMINATED: | |
419 | return SUCCESS; | |
420 | case CHECK_CONDITION: | |
421 | return scsi_check_sense(scmd); | |
422 | case CONDITION_GOOD: | |
423 | case INTERMEDIATE_GOOD: | |
424 | case INTERMEDIATE_C_GOOD: | |
425 | /* | |
426 | * who knows? FIXME(eric) | |
427 | */ | |
428 | return SUCCESS; | |
429 | case BUSY: | |
430 | case QUEUE_FULL: | |
431 | case RESERVATION_CONFLICT: | |
432 | default: | |
433 | return FAILED; | |
434 | } | |
435 | return FAILED; | |
436 | } | |
437 | ||
1da177e4 LT |
438 | /** |
439 | * scsi_eh_done - Completion function for error handling. | |
440 | * @scmd: Cmd that is done. | |
441 | **/ | |
442 | static void scsi_eh_done(struct scsi_cmnd *scmd) | |
443 | { | |
85631672 MR |
444 | struct completion *eh_action; |
445 | ||
7dfdc9a5 CH |
446 | SCSI_LOG_ERROR_RECOVERY(3, |
447 | printk("%s scmd: %p result: %x\n", | |
448 | __FUNCTION__, scmd, scmd->result)); | |
85631672 MR |
449 | |
450 | eh_action = scmd->device->host->eh_action; | |
451 | if (eh_action) | |
452 | complete(eh_action); | |
1da177e4 LT |
453 | } |
454 | ||
455 | /** | |
456 | * scsi_send_eh_cmnd - send a cmd to a device as part of error recovery. | |
457 | * @scmd: SCSI Cmd to send. | |
458 | * @timeout: Timeout for cmd. | |
459 | * | |
1da177e4 LT |
460 | * Return value: |
461 | * SUCCESS or FAILED or NEEDS_RETRY | |
462 | **/ | |
463 | static int scsi_send_eh_cmnd(struct scsi_cmnd *scmd, int timeout) | |
464 | { | |
f59114b7 | 465 | struct scsi_device *sdev = scmd->device; |
466 | struct Scsi_Host *shost = sdev->host; | |
7dfdc9a5 CH |
467 | DECLARE_COMPLETION(done); |
468 | unsigned long timeleft; | |
1da177e4 | 469 | unsigned long flags; |
7dfdc9a5 | 470 | int rtn; |
1da177e4 | 471 | |
f59114b7 | 472 | if (sdev->scsi_level <= SCSI_2) |
1da177e4 | 473 | scmd->cmnd[1] = (scmd->cmnd[1] & 0x1f) | |
f59114b7 | 474 | (sdev->lun << 5 & 0xe0); |
1da177e4 | 475 | |
7dfdc9a5 | 476 | shost->eh_action = &done; |
1da177e4 | 477 | |
f59114b7 | 478 | spin_lock_irqsave(shost->host_lock, flags); |
1da177e4 | 479 | scsi_log_send(scmd); |
f59114b7 | 480 | shost->hostt->queuecommand(scmd, scsi_eh_done); |
481 | spin_unlock_irqrestore(shost->host_lock, flags); | |
1da177e4 | 482 | |
7dfdc9a5 | 483 | timeleft = wait_for_completion_timeout(&done, timeout); |
1da177e4 | 484 | |
f59114b7 | 485 | shost->eh_action = NULL; |
1da177e4 | 486 | |
7dfdc9a5 | 487 | scsi_log_completion(scmd, SUCCESS); |
1da177e4 | 488 | |
7dfdc9a5 CH |
489 | SCSI_LOG_ERROR_RECOVERY(3, |
490 | printk("%s: scmd: %p, timeleft: %ld\n", | |
491 | __FUNCTION__, scmd, timeleft)); | |
1da177e4 LT |
492 | |
493 | /* | |
7dfdc9a5 CH |
494 | * If there is time left scsi_eh_done got called, and we will |
495 | * examine the actual status codes to see whether the command | |
496 | * actually did complete normally, else tell the host to forget | |
497 | * about this command. | |
1da177e4 | 498 | */ |
7dfdc9a5 | 499 | if (timeleft) { |
1da177e4 LT |
500 | rtn = scsi_eh_completed_normally(scmd); |
501 | SCSI_LOG_ERROR_RECOVERY(3, | |
502 | printk("%s: scsi_eh_completed_normally %x\n", | |
503 | __FUNCTION__, rtn)); | |
7dfdc9a5 | 504 | |
1da177e4 LT |
505 | switch (rtn) { |
506 | case SUCCESS: | |
507 | case NEEDS_RETRY: | |
508 | case FAILED: | |
509 | break; | |
510 | default: | |
511 | rtn = FAILED; | |
512 | break; | |
513 | } | |
7dfdc9a5 CH |
514 | } else { |
515 | /* | |
516 | * FIXME(eric) - we are not tracking whether we could | |
517 | * abort a timed out command or not. not sure how | |
518 | * we should treat them differently anyways. | |
519 | */ | |
520 | if (shost->hostt->eh_abort_handler) | |
521 | shost->hostt->eh_abort_handler(scmd); | |
522 | rtn = FAILED; | |
1da177e4 LT |
523 | } |
524 | ||
525 | return rtn; | |
526 | } | |
527 | ||
528 | /** | |
529 | * scsi_request_sense - Request sense data from a particular target. | |
530 | * @scmd: SCSI cmd for request sense. | |
531 | * | |
532 | * Notes: | |
533 | * Some hosts automatically obtain this information, others require | |
534 | * that we obtain it on our own. This function will *not* return until | |
535 | * the command either times out, or it completes. | |
536 | **/ | |
537 | static int scsi_request_sense(struct scsi_cmnd *scmd) | |
538 | { | |
539 | static unsigned char generic_sense[6] = | |
540 | {REQUEST_SENSE, 0, 0, 0, 252, 0}; | |
541 | unsigned char *scsi_result; | |
542 | int saved_result; | |
543 | int rtn; | |
544 | ||
545 | memcpy(scmd->cmnd, generic_sense, sizeof(generic_sense)); | |
546 | ||
bc86120a | 547 | scsi_result = kmalloc(252, GFP_ATOMIC | ((scmd->device->host->hostt->unchecked_isa_dma) ? __GFP_DMA : 0)); |
1da177e4 LT |
548 | |
549 | ||
550 | if (unlikely(!scsi_result)) { | |
551 | printk(KERN_ERR "%s: cannot allocate scsi_result.\n", | |
552 | __FUNCTION__); | |
553 | return FAILED; | |
554 | } | |
555 | ||
556 | /* | |
557 | * zero the sense buffer. some host adapters automatically always | |
558 | * request sense, so it is not a good idea that | |
559 | * scmd->request_buffer and scmd->sense_buffer point to the same | |
560 | * address (db). 0 is not a valid sense code. | |
561 | */ | |
562 | memset(scmd->sense_buffer, 0, sizeof(scmd->sense_buffer)); | |
563 | memset(scsi_result, 0, 252); | |
564 | ||
565 | saved_result = scmd->result; | |
566 | scmd->request_buffer = scsi_result; | |
567 | scmd->request_bufflen = 252; | |
568 | scmd->use_sg = 0; | |
569 | scmd->cmd_len = COMMAND_SIZE(scmd->cmnd[0]); | |
570 | scmd->sc_data_direction = DMA_FROM_DEVICE; | |
571 | scmd->underflow = 0; | |
572 | ||
573 | rtn = scsi_send_eh_cmnd(scmd, SENSE_TIMEOUT); | |
574 | ||
575 | /* last chance to have valid sense data */ | |
576 | if(!SCSI_SENSE_VALID(scmd)) { | |
577 | memcpy(scmd->sense_buffer, scmd->request_buffer, | |
578 | sizeof(scmd->sense_buffer)); | |
579 | } | |
580 | ||
581 | kfree(scsi_result); | |
582 | ||
583 | /* | |
584 | * when we eventually call scsi_finish, we really wish to complete | |
585 | * the original request, so let's restore the original data. (db) | |
586 | */ | |
587 | scsi_setup_cmd_retry(scmd); | |
588 | scmd->result = saved_result; | |
589 | return rtn; | |
590 | } | |
591 | ||
592 | /** | |
593 | * scsi_eh_finish_cmd - Handle a cmd that eh is finished with. | |
594 | * @scmd: Original SCSI cmd that eh has finished. | |
595 | * @done_q: Queue for processed commands. | |
596 | * | |
597 | * Notes: | |
598 | * We don't want to use the normal command completion while we are are | |
599 | * still handling errors - it may cause other commands to be queued, | |
600 | * and that would disturb what we are doing. thus we really want to | |
601 | * keep a list of pending commands for final completion, and once we | |
602 | * are ready to leave error handling we handle completion for real. | |
603 | **/ | |
041c5fc3 | 604 | void scsi_eh_finish_cmd(struct scsi_cmnd *scmd, struct list_head *done_q) |
1da177e4 LT |
605 | { |
606 | scmd->device->host->host_failed--; | |
3111b0d1 | 607 | scmd->eh_eflags = 0; |
1da177e4 LT |
608 | |
609 | /* | |
610 | * set this back so that the upper level can correctly free up | |
611 | * things. | |
612 | */ | |
613 | scsi_setup_cmd_retry(scmd); | |
614 | list_move_tail(&scmd->eh_entry, done_q); | |
615 | } | |
041c5fc3 | 616 | EXPORT_SYMBOL(scsi_eh_finish_cmd); |
1da177e4 LT |
617 | |
618 | /** | |
619 | * scsi_eh_get_sense - Get device sense data. | |
620 | * @work_q: Queue of commands to process. | |
621 | * @done_q: Queue of proccessed commands.. | |
622 | * | |
623 | * Description: | |
624 | * See if we need to request sense information. if so, then get it | |
625 | * now, so we have a better idea of what to do. | |
626 | * | |
627 | * Notes: | |
628 | * This has the unfortunate side effect that if a shost adapter does | |
629 | * not automatically request sense information, that we end up shutting | |
630 | * it down before we request it. | |
631 | * | |
632 | * All drivers should request sense information internally these days, | |
633 | * so for now all I have to say is tough noogies if you end up in here. | |
634 | * | |
635 | * XXX: Long term this code should go away, but that needs an audit of | |
636 | * all LLDDs first. | |
637 | **/ | |
638 | static int scsi_eh_get_sense(struct list_head *work_q, | |
639 | struct list_head *done_q) | |
640 | { | |
937abeaa | 641 | struct scsi_cmnd *scmd, *next; |
1da177e4 LT |
642 | int rtn; |
643 | ||
937abeaa | 644 | list_for_each_entry_safe(scmd, next, work_q, eh_entry) { |
3111b0d1 | 645 | if ((scmd->eh_eflags & SCSI_EH_CANCEL_CMD) || |
1da177e4 LT |
646 | SCSI_SENSE_VALID(scmd)) |
647 | continue; | |
648 | ||
3bf743e7 JG |
649 | SCSI_LOG_ERROR_RECOVERY(2, scmd_printk(KERN_INFO, scmd, |
650 | "%s: requesting sense\n", | |
651 | current->comm)); | |
1da177e4 LT |
652 | rtn = scsi_request_sense(scmd); |
653 | if (rtn != SUCCESS) | |
654 | continue; | |
655 | ||
656 | SCSI_LOG_ERROR_RECOVERY(3, printk("sense requested for %p" | |
657 | " result %x\n", scmd, | |
658 | scmd->result)); | |
659 | SCSI_LOG_ERROR_RECOVERY(3, scsi_print_sense("bh", scmd)); | |
660 | ||
661 | rtn = scsi_decide_disposition(scmd); | |
662 | ||
663 | /* | |
664 | * if the result was normal, then just pass it along to the | |
665 | * upper level. | |
666 | */ | |
667 | if (rtn == SUCCESS) | |
668 | /* we don't want this command reissued, just | |
669 | * finished with the sense data, so set | |
670 | * retries to the max allowed to ensure it | |
671 | * won't get reissued */ | |
672 | scmd->retries = scmd->allowed; | |
673 | else if (rtn != NEEDS_RETRY) | |
674 | continue; | |
675 | ||
676 | scsi_eh_finish_cmd(scmd, done_q); | |
677 | } | |
678 | ||
679 | return list_empty(work_q); | |
680 | } | |
681 | ||
682 | /** | |
683 | * scsi_try_to_abort_cmd - Ask host to abort a running command. | |
684 | * @scmd: SCSI cmd to abort from Lower Level. | |
685 | * | |
686 | * Notes: | |
687 | * This function will not return until the user's completion function | |
688 | * has been called. there is no timeout on this operation. if the | |
689 | * author of the low-level driver wishes this operation to be timed, | |
690 | * they can provide this facility themselves. helper functions in | |
691 | * scsi_error.c can be supplied to make this easier to do. | |
692 | **/ | |
693 | static int scsi_try_to_abort_cmd(struct scsi_cmnd *scmd) | |
694 | { | |
1da177e4 | 695 | if (!scmd->device->host->hostt->eh_abort_handler) |
8fa728a2 | 696 | return FAILED; |
1da177e4 LT |
697 | |
698 | /* | |
699 | * scsi_done was called just after the command timed out and before | |
700 | * we had a chance to process it. (db) | |
701 | */ | |
702 | if (scmd->serial_number == 0) | |
703 | return SUCCESS; | |
8fa728a2 | 704 | return scmd->device->host->hostt->eh_abort_handler(scmd); |
1da177e4 LT |
705 | } |
706 | ||
707 | /** | |
708 | * scsi_eh_tur - Send TUR to device. | |
709 | * @scmd: Scsi cmd to send TUR | |
710 | * | |
711 | * Return value: | |
712 | * 0 - Device is ready. 1 - Device NOT ready. | |
713 | **/ | |
714 | static int scsi_eh_tur(struct scsi_cmnd *scmd) | |
715 | { | |
716 | static unsigned char tur_command[6] = {TEST_UNIT_READY, 0, 0, 0, 0, 0}; | |
717 | int retry_cnt = 1, rtn; | |
793698ce | 718 | int saved_result; |
1da177e4 LT |
719 | |
720 | retry_tur: | |
721 | memcpy(scmd->cmnd, tur_command, sizeof(tur_command)); | |
722 | ||
723 | /* | |
724 | * zero the sense buffer. the scsi spec mandates that any | |
725 | * untransferred sense data should be interpreted as being zero. | |
726 | */ | |
727 | memset(scmd->sense_buffer, 0, sizeof(scmd->sense_buffer)); | |
728 | ||
793698ce | 729 | saved_result = scmd->result; |
1da177e4 LT |
730 | scmd->request_buffer = NULL; |
731 | scmd->request_bufflen = 0; | |
732 | scmd->use_sg = 0; | |
733 | scmd->cmd_len = COMMAND_SIZE(scmd->cmnd[0]); | |
734 | scmd->underflow = 0; | |
735 | scmd->sc_data_direction = DMA_NONE; | |
736 | ||
737 | rtn = scsi_send_eh_cmnd(scmd, SENSE_TIMEOUT); | |
738 | ||
739 | /* | |
740 | * when we eventually call scsi_finish, we really wish to complete | |
741 | * the original request, so let's restore the original data. (db) | |
742 | */ | |
743 | scsi_setup_cmd_retry(scmd); | |
793698ce | 744 | scmd->result = saved_result; |
1da177e4 LT |
745 | |
746 | /* | |
747 | * hey, we are done. let's look to see what happened. | |
748 | */ | |
749 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: scmd %p rtn %x\n", | |
750 | __FUNCTION__, scmd, rtn)); | |
751 | if (rtn == SUCCESS) | |
752 | return 0; | |
e47373ec | 753 | else if (rtn == NEEDS_RETRY) { |
1da177e4 LT |
754 | if (retry_cnt--) |
755 | goto retry_tur; | |
e47373ec AS |
756 | return 0; |
757 | } | |
1da177e4 LT |
758 | return 1; |
759 | } | |
760 | ||
761 | /** | |
762 | * scsi_eh_abort_cmds - abort canceled commands. | |
763 | * @shost: scsi host being recovered. | |
764 | * @eh_done_q: list_head for processed commands. | |
765 | * | |
766 | * Decription: | |
767 | * Try and see whether or not it makes sense to try and abort the | |
768 | * running command. this only works out to be the case if we have one | |
769 | * command that has timed out. if the command simply failed, it makes | |
770 | * no sense to try and abort the command, since as far as the shost | |
771 | * adapter is concerned, it isn't running. | |
772 | **/ | |
773 | static int scsi_eh_abort_cmds(struct list_head *work_q, | |
774 | struct list_head *done_q) | |
775 | { | |
937abeaa | 776 | struct scsi_cmnd *scmd, *next; |
1da177e4 LT |
777 | int rtn; |
778 | ||
937abeaa | 779 | list_for_each_entry_safe(scmd, next, work_q, eh_entry) { |
3111b0d1 | 780 | if (!(scmd->eh_eflags & SCSI_EH_CANCEL_CMD)) |
1da177e4 LT |
781 | continue; |
782 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: aborting cmd:" | |
783 | "0x%p\n", current->comm, | |
784 | scmd)); | |
785 | rtn = scsi_try_to_abort_cmd(scmd); | |
786 | if (rtn == SUCCESS) { | |
3111b0d1 | 787 | scmd->eh_eflags &= ~SCSI_EH_CANCEL_CMD; |
1da177e4 LT |
788 | if (!scsi_device_online(scmd->device) || |
789 | !scsi_eh_tur(scmd)) { | |
790 | scsi_eh_finish_cmd(scmd, done_q); | |
791 | } | |
792 | ||
793 | } else | |
794 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: aborting" | |
795 | " cmd failed:" | |
796 | "0x%p\n", | |
797 | current->comm, | |
798 | scmd)); | |
799 | } | |
800 | ||
801 | return list_empty(work_q); | |
802 | } | |
803 | ||
804 | /** | |
805 | * scsi_try_bus_device_reset - Ask host to perform a BDR on a dev | |
806 | * @scmd: SCSI cmd used to send BDR | |
807 | * | |
808 | * Notes: | |
809 | * There is no timeout for this operation. if this operation is | |
810 | * unreliable for a given host, then the host itself needs to put a | |
811 | * timer on it, and set the host back to a consistent state prior to | |
812 | * returning. | |
813 | **/ | |
814 | static int scsi_try_bus_device_reset(struct scsi_cmnd *scmd) | |
815 | { | |
94d0e7b8 | 816 | int rtn; |
1da177e4 LT |
817 | |
818 | if (!scmd->device->host->hostt->eh_device_reset_handler) | |
94d0e7b8 | 819 | return FAILED; |
1da177e4 | 820 | |
1da177e4 | 821 | rtn = scmd->device->host->hostt->eh_device_reset_handler(scmd); |
1da177e4 LT |
822 | if (rtn == SUCCESS) { |
823 | scmd->device->was_reset = 1; | |
824 | scmd->device->expecting_cc_ua = 1; | |
825 | } | |
826 | ||
827 | return rtn; | |
828 | } | |
829 | ||
830 | /** | |
831 | * scsi_eh_try_stu - Send START_UNIT to device. | |
832 | * @scmd: Scsi cmd to send START_UNIT | |
833 | * | |
834 | * Return value: | |
835 | * 0 - Device is ready. 1 - Device NOT ready. | |
836 | **/ | |
837 | static int scsi_eh_try_stu(struct scsi_cmnd *scmd) | |
838 | { | |
839 | static unsigned char stu_command[6] = {START_STOP, 0, 0, 0, 1, 0}; | |
840 | int rtn; | |
793698ce | 841 | int saved_result; |
1da177e4 LT |
842 | |
843 | if (!scmd->device->allow_restart) | |
844 | return 1; | |
845 | ||
846 | memcpy(scmd->cmnd, stu_command, sizeof(stu_command)); | |
847 | ||
848 | /* | |
849 | * zero the sense buffer. the scsi spec mandates that any | |
850 | * untransferred sense data should be interpreted as being zero. | |
851 | */ | |
852 | memset(scmd->sense_buffer, 0, sizeof(scmd->sense_buffer)); | |
853 | ||
793698ce | 854 | saved_result = scmd->result; |
1da177e4 LT |
855 | scmd->request_buffer = NULL; |
856 | scmd->request_bufflen = 0; | |
857 | scmd->use_sg = 0; | |
858 | scmd->cmd_len = COMMAND_SIZE(scmd->cmnd[0]); | |
859 | scmd->underflow = 0; | |
860 | scmd->sc_data_direction = DMA_NONE; | |
861 | ||
862 | rtn = scsi_send_eh_cmnd(scmd, START_UNIT_TIMEOUT); | |
863 | ||
864 | /* | |
865 | * when we eventually call scsi_finish, we really wish to complete | |
866 | * the original request, so let's restore the original data. (db) | |
867 | */ | |
868 | scsi_setup_cmd_retry(scmd); | |
793698ce | 869 | scmd->result = saved_result; |
1da177e4 LT |
870 | |
871 | /* | |
872 | * hey, we are done. let's look to see what happened. | |
873 | */ | |
874 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: scmd %p rtn %x\n", | |
875 | __FUNCTION__, scmd, rtn)); | |
876 | if (rtn == SUCCESS) | |
877 | return 0; | |
878 | return 1; | |
879 | } | |
880 | ||
881 | /** | |
882 | * scsi_eh_stu - send START_UNIT if needed | |
883 | * @shost: scsi host being recovered. | |
884 | * @eh_done_q: list_head for processed commands. | |
885 | * | |
886 | * Notes: | |
887 | * If commands are failing due to not ready, initializing command required, | |
888 | * try revalidating the device, which will end up sending a start unit. | |
889 | **/ | |
890 | static int scsi_eh_stu(struct Scsi_Host *shost, | |
891 | struct list_head *work_q, | |
892 | struct list_head *done_q) | |
893 | { | |
937abeaa | 894 | struct scsi_cmnd *scmd, *stu_scmd, *next; |
1da177e4 LT |
895 | struct scsi_device *sdev; |
896 | ||
897 | shost_for_each_device(sdev, shost) { | |
898 | stu_scmd = NULL; | |
899 | list_for_each_entry(scmd, work_q, eh_entry) | |
900 | if (scmd->device == sdev && SCSI_SENSE_VALID(scmd) && | |
901 | scsi_check_sense(scmd) == FAILED ) { | |
902 | stu_scmd = scmd; | |
903 | break; | |
904 | } | |
905 | ||
906 | if (!stu_scmd) | |
907 | continue; | |
908 | ||
909 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending START_UNIT to sdev:" | |
910 | " 0x%p\n", current->comm, sdev)); | |
911 | ||
912 | if (!scsi_eh_try_stu(stu_scmd)) { | |
913 | if (!scsi_device_online(sdev) || | |
914 | !scsi_eh_tur(stu_scmd)) { | |
937abeaa CH |
915 | list_for_each_entry_safe(scmd, next, |
916 | work_q, eh_entry) { | |
1da177e4 LT |
917 | if (scmd->device == sdev) |
918 | scsi_eh_finish_cmd(scmd, done_q); | |
919 | } | |
920 | } | |
921 | } else { | |
922 | SCSI_LOG_ERROR_RECOVERY(3, | |
923 | printk("%s: START_UNIT failed to sdev:" | |
924 | " 0x%p\n", current->comm, sdev)); | |
925 | } | |
926 | } | |
927 | ||
928 | return list_empty(work_q); | |
929 | } | |
930 | ||
931 | ||
932 | /** | |
933 | * scsi_eh_bus_device_reset - send bdr if needed | |
934 | * @shost: scsi host being recovered. | |
935 | * @eh_done_q: list_head for processed commands. | |
936 | * | |
937 | * Notes: | |
938 | * Try a bus device reset. still, look to see whether we have multiple | |
939 | * devices that are jammed or not - if we have multiple devices, it | |
940 | * makes no sense to try bus_device_reset - we really would need to try | |
941 | * a bus_reset instead. | |
942 | **/ | |
943 | static int scsi_eh_bus_device_reset(struct Scsi_Host *shost, | |
944 | struct list_head *work_q, | |
945 | struct list_head *done_q) | |
946 | { | |
937abeaa | 947 | struct scsi_cmnd *scmd, *bdr_scmd, *next; |
1da177e4 LT |
948 | struct scsi_device *sdev; |
949 | int rtn; | |
950 | ||
951 | shost_for_each_device(sdev, shost) { | |
952 | bdr_scmd = NULL; | |
953 | list_for_each_entry(scmd, work_q, eh_entry) | |
954 | if (scmd->device == sdev) { | |
955 | bdr_scmd = scmd; | |
956 | break; | |
957 | } | |
958 | ||
959 | if (!bdr_scmd) | |
960 | continue; | |
961 | ||
962 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending BDR sdev:" | |
963 | " 0x%p\n", current->comm, | |
964 | sdev)); | |
965 | rtn = scsi_try_bus_device_reset(bdr_scmd); | |
966 | if (rtn == SUCCESS) { | |
967 | if (!scsi_device_online(sdev) || | |
968 | !scsi_eh_tur(bdr_scmd)) { | |
937abeaa CH |
969 | list_for_each_entry_safe(scmd, next, |
970 | work_q, eh_entry) { | |
1da177e4 LT |
971 | if (scmd->device == sdev) |
972 | scsi_eh_finish_cmd(scmd, | |
973 | done_q); | |
974 | } | |
975 | } | |
976 | } else { | |
977 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: BDR" | |
978 | " failed sdev:" | |
979 | "0x%p\n", | |
980 | current->comm, | |
981 | sdev)); | |
982 | } | |
983 | } | |
984 | ||
985 | return list_empty(work_q); | |
986 | } | |
987 | ||
988 | /** | |
989 | * scsi_try_bus_reset - ask host to perform a bus reset | |
990 | * @scmd: SCSI cmd to send bus reset. | |
991 | **/ | |
992 | static int scsi_try_bus_reset(struct scsi_cmnd *scmd) | |
993 | { | |
994 | unsigned long flags; | |
995 | int rtn; | |
996 | ||
997 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Snd Bus RST\n", | |
998 | __FUNCTION__)); | |
1da177e4 LT |
999 | |
1000 | if (!scmd->device->host->hostt->eh_bus_reset_handler) | |
1001 | return FAILED; | |
1002 | ||
1da177e4 | 1003 | rtn = scmd->device->host->hostt->eh_bus_reset_handler(scmd); |
1da177e4 LT |
1004 | |
1005 | if (rtn == SUCCESS) { | |
1006 | if (!scmd->device->host->hostt->skip_settle_delay) | |
1007 | ssleep(BUS_RESET_SETTLE_TIME); | |
1008 | spin_lock_irqsave(scmd->device->host->host_lock, flags); | |
422c0d61 JG |
1009 | scsi_report_bus_reset(scmd->device->host, |
1010 | scmd_channel(scmd)); | |
1da177e4 LT |
1011 | spin_unlock_irqrestore(scmd->device->host->host_lock, flags); |
1012 | } | |
1013 | ||
1014 | return rtn; | |
1015 | } | |
1016 | ||
1017 | /** | |
1018 | * scsi_try_host_reset - ask host adapter to reset itself | |
1019 | * @scmd: SCSI cmd to send hsot reset. | |
1020 | **/ | |
1021 | static int scsi_try_host_reset(struct scsi_cmnd *scmd) | |
1022 | { | |
1023 | unsigned long flags; | |
1024 | int rtn; | |
1025 | ||
1026 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Snd Host RST\n", | |
1027 | __FUNCTION__)); | |
1da177e4 LT |
1028 | |
1029 | if (!scmd->device->host->hostt->eh_host_reset_handler) | |
1030 | return FAILED; | |
1031 | ||
1da177e4 | 1032 | rtn = scmd->device->host->hostt->eh_host_reset_handler(scmd); |
1da177e4 LT |
1033 | |
1034 | if (rtn == SUCCESS) { | |
1035 | if (!scmd->device->host->hostt->skip_settle_delay) | |
1036 | ssleep(HOST_RESET_SETTLE_TIME); | |
1037 | spin_lock_irqsave(scmd->device->host->host_lock, flags); | |
422c0d61 JG |
1038 | scsi_report_bus_reset(scmd->device->host, |
1039 | scmd_channel(scmd)); | |
1da177e4 LT |
1040 | spin_unlock_irqrestore(scmd->device->host->host_lock, flags); |
1041 | } | |
1042 | ||
1043 | return rtn; | |
1044 | } | |
1045 | ||
1046 | /** | |
1047 | * scsi_eh_bus_reset - send a bus reset | |
1048 | * @shost: scsi host being recovered. | |
1049 | * @eh_done_q: list_head for processed commands. | |
1050 | **/ | |
1051 | static int scsi_eh_bus_reset(struct Scsi_Host *shost, | |
1052 | struct list_head *work_q, | |
1053 | struct list_head *done_q) | |
1054 | { | |
937abeaa | 1055 | struct scsi_cmnd *scmd, *chan_scmd, *next; |
1da177e4 LT |
1056 | unsigned int channel; |
1057 | int rtn; | |
1058 | ||
1059 | /* | |
1060 | * we really want to loop over the various channels, and do this on | |
1061 | * a channel by channel basis. we should also check to see if any | |
1062 | * of the failed commands are on soft_reset devices, and if so, skip | |
1063 | * the reset. | |
1064 | */ | |
1065 | ||
1066 | for (channel = 0; channel <= shost->max_channel; channel++) { | |
1067 | chan_scmd = NULL; | |
1068 | list_for_each_entry(scmd, work_q, eh_entry) { | |
422c0d61 | 1069 | if (channel == scmd_channel(scmd)) { |
1da177e4 LT |
1070 | chan_scmd = scmd; |
1071 | break; | |
1072 | /* | |
1073 | * FIXME add back in some support for | |
1074 | * soft_reset devices. | |
1075 | */ | |
1076 | } | |
1077 | } | |
1078 | ||
1079 | if (!chan_scmd) | |
1080 | continue; | |
1081 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending BRST chan:" | |
1082 | " %d\n", current->comm, | |
1083 | channel)); | |
1084 | rtn = scsi_try_bus_reset(chan_scmd); | |
1085 | if (rtn == SUCCESS) { | |
937abeaa | 1086 | list_for_each_entry_safe(scmd, next, work_q, eh_entry) { |
422c0d61 | 1087 | if (channel == scmd_channel(scmd)) |
1da177e4 LT |
1088 | if (!scsi_device_online(scmd->device) || |
1089 | !scsi_eh_tur(scmd)) | |
1090 | scsi_eh_finish_cmd(scmd, | |
1091 | done_q); | |
1092 | } | |
1093 | } else { | |
1094 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: BRST" | |
1095 | " failed chan: %d\n", | |
1096 | current->comm, | |
1097 | channel)); | |
1098 | } | |
1099 | } | |
1100 | return list_empty(work_q); | |
1101 | } | |
1102 | ||
1103 | /** | |
1104 | * scsi_eh_host_reset - send a host reset | |
1105 | * @work_q: list_head for processed commands. | |
1106 | * @done_q: list_head for processed commands. | |
1107 | **/ | |
1108 | static int scsi_eh_host_reset(struct list_head *work_q, | |
1109 | struct list_head *done_q) | |
1110 | { | |
937abeaa | 1111 | struct scsi_cmnd *scmd, *next; |
1da177e4 | 1112 | int rtn; |
1da177e4 LT |
1113 | |
1114 | if (!list_empty(work_q)) { | |
1115 | scmd = list_entry(work_q->next, | |
1116 | struct scsi_cmnd, eh_entry); | |
1117 | ||
1118 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending HRST\n" | |
1119 | , current->comm)); | |
1120 | ||
1121 | rtn = scsi_try_host_reset(scmd); | |
1122 | if (rtn == SUCCESS) { | |
937abeaa | 1123 | list_for_each_entry_safe(scmd, next, work_q, eh_entry) { |
1da177e4 LT |
1124 | if (!scsi_device_online(scmd->device) || |
1125 | (!scsi_eh_try_stu(scmd) && !scsi_eh_tur(scmd)) || | |
1126 | !scsi_eh_tur(scmd)) | |
1127 | scsi_eh_finish_cmd(scmd, done_q); | |
1128 | } | |
1129 | } else { | |
1130 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: HRST" | |
1131 | " failed\n", | |
1132 | current->comm)); | |
1133 | } | |
1134 | } | |
1135 | return list_empty(work_q); | |
1136 | } | |
1137 | ||
1138 | /** | |
1139 | * scsi_eh_offline_sdevs - offline scsi devices that fail to recover | |
1140 | * @work_q: list_head for processed commands. | |
1141 | * @done_q: list_head for processed commands. | |
1142 | * | |
1143 | **/ | |
1144 | static void scsi_eh_offline_sdevs(struct list_head *work_q, | |
1145 | struct list_head *done_q) | |
1146 | { | |
937abeaa | 1147 | struct scsi_cmnd *scmd, *next; |
1da177e4 | 1148 | |
937abeaa | 1149 | list_for_each_entry_safe(scmd, next, work_q, eh_entry) { |
9ccfc756 JB |
1150 | sdev_printk(KERN_INFO, scmd->device, |
1151 | "scsi: Device offlined - not" | |
1152 | " ready after error recovery\n"); | |
1da177e4 | 1153 | scsi_device_set_state(scmd->device, SDEV_OFFLINE); |
3111b0d1 | 1154 | if (scmd->eh_eflags & SCSI_EH_CANCEL_CMD) { |
1da177e4 LT |
1155 | /* |
1156 | * FIXME: Handle lost cmds. | |
1157 | */ | |
1158 | } | |
1159 | scsi_eh_finish_cmd(scmd, done_q); | |
1160 | } | |
1161 | return; | |
1162 | } | |
1163 | ||
1164 | /** | |
1165 | * scsi_decide_disposition - Disposition a cmd on return from LLD. | |
1166 | * @scmd: SCSI cmd to examine. | |
1167 | * | |
1168 | * Notes: | |
1169 | * This is *only* called when we are examining the status after sending | |
1170 | * out the actual data command. any commands that are queued for error | |
1171 | * recovery (e.g. test_unit_ready) do *not* come through here. | |
1172 | * | |
1173 | * When this routine returns failed, it means the error handler thread | |
1174 | * is woken. In cases where the error code indicates an error that | |
1175 | * doesn't require the error handler read (i.e. we don't need to | |
1176 | * abort/reset), this function should return SUCCESS. | |
1177 | **/ | |
1178 | int scsi_decide_disposition(struct scsi_cmnd *scmd) | |
1179 | { | |
1180 | int rtn; | |
1181 | ||
1182 | /* | |
1183 | * if the device is offline, then we clearly just pass the result back | |
1184 | * up to the top level. | |
1185 | */ | |
1186 | if (!scsi_device_online(scmd->device)) { | |
1187 | SCSI_LOG_ERROR_RECOVERY(5, printk("%s: device offline - report" | |
1188 | " as SUCCESS\n", | |
1189 | __FUNCTION__)); | |
1190 | return SUCCESS; | |
1191 | } | |
1192 | ||
1193 | /* | |
1194 | * first check the host byte, to see if there is anything in there | |
1195 | * that would indicate what we need to do. | |
1196 | */ | |
1197 | switch (host_byte(scmd->result)) { | |
1198 | case DID_PASSTHROUGH: | |
1199 | /* | |
1200 | * no matter what, pass this through to the upper layer. | |
1201 | * nuke this special code so that it looks like we are saying | |
1202 | * did_ok. | |
1203 | */ | |
1204 | scmd->result &= 0xff00ffff; | |
1205 | return SUCCESS; | |
1206 | case DID_OK: | |
1207 | /* | |
1208 | * looks good. drop through, and check the next byte. | |
1209 | */ | |
1210 | break; | |
1211 | case DID_NO_CONNECT: | |
1212 | case DID_BAD_TARGET: | |
1213 | case DID_ABORT: | |
1214 | /* | |
1215 | * note - this means that we just report the status back | |
1216 | * to the top level driver, not that we actually think | |
1217 | * that it indicates SUCCESS. | |
1218 | */ | |
1219 | return SUCCESS; | |
1220 | /* | |
1221 | * when the low level driver returns did_soft_error, | |
1222 | * it is responsible for keeping an internal retry counter | |
1223 | * in order to avoid endless loops (db) | |
1224 | * | |
1225 | * actually this is a bug in this function here. we should | |
1226 | * be mindful of the maximum number of retries specified | |
1227 | * and not get stuck in a loop. | |
1228 | */ | |
1229 | case DID_SOFT_ERROR: | |
1230 | goto maybe_retry; | |
1231 | case DID_IMM_RETRY: | |
1232 | return NEEDS_RETRY; | |
1233 | ||
bf341919 | 1234 | case DID_REQUEUE: |
1235 | return ADD_TO_MLQUEUE; | |
1236 | ||
1da177e4 LT |
1237 | case DID_ERROR: |
1238 | if (msg_byte(scmd->result) == COMMAND_COMPLETE && | |
1239 | status_byte(scmd->result) == RESERVATION_CONFLICT) | |
1240 | /* | |
1241 | * execute reservation conflict processing code | |
1242 | * lower down | |
1243 | */ | |
1244 | break; | |
1245 | /* fallthrough */ | |
1246 | ||
1247 | case DID_BUS_BUSY: | |
1248 | case DID_PARITY: | |
1249 | goto maybe_retry; | |
1250 | case DID_TIME_OUT: | |
1251 | /* | |
1252 | * when we scan the bus, we get timeout messages for | |
1253 | * these commands if there is no device available. | |
1254 | * other hosts report did_no_connect for the same thing. | |
1255 | */ | |
1256 | if ((scmd->cmnd[0] == TEST_UNIT_READY || | |
1257 | scmd->cmnd[0] == INQUIRY)) { | |
1258 | return SUCCESS; | |
1259 | } else { | |
1260 | return FAILED; | |
1261 | } | |
1262 | case DID_RESET: | |
1263 | return SUCCESS; | |
1264 | default: | |
1265 | return FAILED; | |
1266 | } | |
1267 | ||
1268 | /* | |
1269 | * next, check the message byte. | |
1270 | */ | |
1271 | if (msg_byte(scmd->result) != COMMAND_COMPLETE) | |
1272 | return FAILED; | |
1273 | ||
1274 | /* | |
1275 | * check the status byte to see if this indicates anything special. | |
1276 | */ | |
1277 | switch (status_byte(scmd->result)) { | |
1278 | case QUEUE_FULL: | |
1279 | /* | |
1280 | * the case of trying to send too many commands to a | |
1281 | * tagged queueing device. | |
1282 | */ | |
1283 | case BUSY: | |
1284 | /* | |
1285 | * device can't talk to us at the moment. Should only | |
1286 | * occur (SAM-3) when the task queue is empty, so will cause | |
1287 | * the empty queue handling to trigger a stall in the | |
1288 | * device. | |
1289 | */ | |
1290 | return ADD_TO_MLQUEUE; | |
1291 | case GOOD: | |
1292 | case COMMAND_TERMINATED: | |
1293 | case TASK_ABORTED: | |
1294 | return SUCCESS; | |
1295 | case CHECK_CONDITION: | |
1296 | rtn = scsi_check_sense(scmd); | |
1297 | if (rtn == NEEDS_RETRY) | |
1298 | goto maybe_retry; | |
1299 | /* if rtn == FAILED, we have no sense information; | |
1300 | * returning FAILED will wake the error handler thread | |
1301 | * to collect the sense and redo the decide | |
1302 | * disposition */ | |
1303 | return rtn; | |
1304 | case CONDITION_GOOD: | |
1305 | case INTERMEDIATE_GOOD: | |
1306 | case INTERMEDIATE_C_GOOD: | |
1307 | case ACA_ACTIVE: | |
1308 | /* | |
1309 | * who knows? FIXME(eric) | |
1310 | */ | |
1311 | return SUCCESS; | |
1312 | ||
1313 | case RESERVATION_CONFLICT: | |
9ccfc756 JB |
1314 | sdev_printk(KERN_INFO, scmd->device, |
1315 | "reservation conflict\n"); | |
1da177e4 LT |
1316 | return SUCCESS; /* causes immediate i/o error */ |
1317 | default: | |
1318 | return FAILED; | |
1319 | } | |
1320 | return FAILED; | |
1321 | ||
1322 | maybe_retry: | |
1323 | ||
1324 | /* we requeue for retry because the error was retryable, and | |
1325 | * the request was not marked fast fail. Note that above, | |
1326 | * even if the request is marked fast fail, we still requeue | |
1327 | * for queue congestion conditions (QUEUE_FULL or BUSY) */ | |
8884efab | 1328 | if ((++scmd->retries) <= scmd->allowed |
1da177e4 LT |
1329 | && !blk_noretry_request(scmd->request)) { |
1330 | return NEEDS_RETRY; | |
1331 | } else { | |
1332 | /* | |
1333 | * no more retries - report this one back to upper level. | |
1334 | */ | |
1335 | return SUCCESS; | |
1336 | } | |
1337 | } | |
1338 | ||
1da177e4 LT |
1339 | /** |
1340 | * scsi_eh_lock_door - Prevent medium removal for the specified device | |
1341 | * @sdev: SCSI device to prevent medium removal | |
1342 | * | |
1343 | * Locking: | |
1344 | * We must be called from process context; scsi_allocate_request() | |
1345 | * may sleep. | |
1346 | * | |
1347 | * Notes: | |
1348 | * We queue up an asynchronous "ALLOW MEDIUM REMOVAL" request on the | |
1349 | * head of the devices request queue, and continue. | |
1350 | * | |
1351 | * Bugs: | |
1352 | * scsi_allocate_request() may sleep waiting for existing requests to | |
1353 | * be processed. However, since we haven't kicked off any request | |
1354 | * processing for this host, this may deadlock. | |
1355 | * | |
1356 | * If scsi_allocate_request() fails for what ever reason, we | |
1357 | * completely forget to lock the door. | |
1358 | **/ | |
1359 | static void scsi_eh_lock_door(struct scsi_device *sdev) | |
1360 | { | |
6e68af66 | 1361 | unsigned char cmnd[MAX_COMMAND_SIZE]; |
1da177e4 | 1362 | |
6e68af66 MC |
1363 | cmnd[0] = ALLOW_MEDIUM_REMOVAL; |
1364 | cmnd[1] = 0; | |
1365 | cmnd[2] = 0; | |
1366 | cmnd[3] = 0; | |
1367 | cmnd[4] = SCSI_REMOVAL_PREVENT; | |
1368 | cmnd[5] = 0; | |
1da177e4 | 1369 | |
bb1d1073 | 1370 | scsi_execute_async(sdev, cmnd, 6, DMA_NONE, NULL, 0, 0, 10 * HZ, |
6e68af66 | 1371 | 5, NULL, NULL, GFP_KERNEL); |
1da177e4 LT |
1372 | } |
1373 | ||
1374 | ||
1375 | /** | |
1376 | * scsi_restart_operations - restart io operations to the specified host. | |
1377 | * @shost: Host we are restarting. | |
1378 | * | |
1379 | * Notes: | |
1380 | * When we entered the error handler, we blocked all further i/o to | |
1381 | * this device. we need to 'reverse' this process. | |
1382 | **/ | |
1383 | static void scsi_restart_operations(struct Scsi_Host *shost) | |
1384 | { | |
1385 | struct scsi_device *sdev; | |
939647ee | 1386 | unsigned long flags; |
1da177e4 LT |
1387 | |
1388 | /* | |
1389 | * If the door was locked, we need to insert a door lock request | |
1390 | * onto the head of the SCSI request queue for the device. There | |
1391 | * is no point trying to lock the door of an off-line device. | |
1392 | */ | |
1393 | shost_for_each_device(sdev, shost) { | |
1394 | if (scsi_device_online(sdev) && sdev->locked) | |
1395 | scsi_eh_lock_door(sdev); | |
1396 | } | |
1397 | ||
1398 | /* | |
1399 | * next free up anything directly waiting upon the host. this | |
1400 | * will be requests for character device operations, and also for | |
1401 | * ioctls to queued block devices. | |
1402 | */ | |
1403 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: waking up host to restart\n", | |
1404 | __FUNCTION__)); | |
1405 | ||
939647ee JB |
1406 | spin_lock_irqsave(shost->host_lock, flags); |
1407 | if (scsi_host_set_state(shost, SHOST_RUNNING)) | |
1408 | if (scsi_host_set_state(shost, SHOST_CANCEL)) | |
1409 | BUG_ON(scsi_host_set_state(shost, SHOST_DEL)); | |
1410 | spin_unlock_irqrestore(shost->host_lock, flags); | |
1da177e4 LT |
1411 | |
1412 | wake_up(&shost->host_wait); | |
1413 | ||
1414 | /* | |
1415 | * finally we need to re-initiate requests that may be pending. we will | |
1416 | * have had everything blocked while error handling is taking place, and | |
1417 | * now that error recovery is done, we will need to ensure that these | |
1418 | * requests are started. | |
1419 | */ | |
1420 | scsi_run_host_queues(shost); | |
1421 | } | |
1422 | ||
1423 | /** | |
1424 | * scsi_eh_ready_devs - check device ready state and recover if not. | |
1425 | * @shost: host to be recovered. | |
1426 | * @eh_done_q: list_head for processed commands. | |
1427 | * | |
1428 | **/ | |
1429 | static void scsi_eh_ready_devs(struct Scsi_Host *shost, | |
1430 | struct list_head *work_q, | |
1431 | struct list_head *done_q) | |
1432 | { | |
1433 | if (!scsi_eh_stu(shost, work_q, done_q)) | |
1434 | if (!scsi_eh_bus_device_reset(shost, work_q, done_q)) | |
1435 | if (!scsi_eh_bus_reset(shost, work_q, done_q)) | |
1436 | if (!scsi_eh_host_reset(work_q, done_q)) | |
1437 | scsi_eh_offline_sdevs(work_q, done_q); | |
1438 | } | |
1439 | ||
1440 | /** | |
1441 | * scsi_eh_flush_done_q - finish processed commands or retry them. | |
1442 | * @done_q: list_head of processed commands. | |
1443 | * | |
1444 | **/ | |
041c5fc3 | 1445 | void scsi_eh_flush_done_q(struct list_head *done_q) |
1da177e4 | 1446 | { |
937abeaa | 1447 | struct scsi_cmnd *scmd, *next; |
1da177e4 | 1448 | |
937abeaa CH |
1449 | list_for_each_entry_safe(scmd, next, done_q, eh_entry) { |
1450 | list_del_init(&scmd->eh_entry); | |
1da177e4 LT |
1451 | if (scsi_device_online(scmd->device) && |
1452 | !blk_noretry_request(scmd->request) && | |
8884efab | 1453 | (++scmd->retries <= scmd->allowed)) { |
1da177e4 LT |
1454 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: flush" |
1455 | " retry cmd: %p\n", | |
1456 | current->comm, | |
1457 | scmd)); | |
1458 | scsi_queue_insert(scmd, SCSI_MLQUEUE_EH_RETRY); | |
1459 | } else { | |
793698ce PM |
1460 | /* |
1461 | * If just we got sense for the device (called | |
1462 | * scsi_eh_get_sense), scmd->result is already | |
1463 | * set, do not set DRIVER_TIMEOUT. | |
1464 | */ | |
1da177e4 LT |
1465 | if (!scmd->result) |
1466 | scmd->result |= (DRIVER_TIMEOUT << 24); | |
1467 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: flush finish" | |
1468 | " cmd: %p\n", | |
1469 | current->comm, scmd)); | |
1470 | scsi_finish_command(scmd); | |
1471 | } | |
1472 | } | |
1473 | } | |
041c5fc3 | 1474 | EXPORT_SYMBOL(scsi_eh_flush_done_q); |
1da177e4 LT |
1475 | |
1476 | /** | |
1477 | * scsi_unjam_host - Attempt to fix a host which has a cmd that failed. | |
1478 | * @shost: Host to unjam. | |
1479 | * | |
1480 | * Notes: | |
1481 | * When we come in here, we *know* that all commands on the bus have | |
1482 | * either completed, failed or timed out. we also know that no further | |
1483 | * commands are being sent to the host, so things are relatively quiet | |
1484 | * and we have freedom to fiddle with things as we wish. | |
1485 | * | |
1486 | * This is only the *default* implementation. it is possible for | |
1487 | * individual drivers to supply their own version of this function, and | |
1488 | * if the maintainer wishes to do this, it is strongly suggested that | |
1489 | * this function be taken as a template and modified. this function | |
1490 | * was designed to correctly handle problems for about 95% of the | |
1491 | * different cases out there, and it should always provide at least a | |
1492 | * reasonable amount of error recovery. | |
1493 | * | |
1494 | * Any command marked 'failed' or 'timeout' must eventually have | |
1495 | * scsi_finish_cmd() called for it. we do all of the retry stuff | |
1496 | * here, so when we restart the host after we return it should have an | |
1497 | * empty queue. | |
1498 | **/ | |
1499 | static void scsi_unjam_host(struct Scsi_Host *shost) | |
1500 | { | |
1501 | unsigned long flags; | |
1502 | LIST_HEAD(eh_work_q); | |
1503 | LIST_HEAD(eh_done_q); | |
1504 | ||
1505 | spin_lock_irqsave(shost->host_lock, flags); | |
1506 | list_splice_init(&shost->eh_cmd_q, &eh_work_q); | |
1507 | spin_unlock_irqrestore(shost->host_lock, flags); | |
1508 | ||
1509 | SCSI_LOG_ERROR_RECOVERY(1, scsi_eh_prt_fail_stats(shost, &eh_work_q)); | |
1510 | ||
1511 | if (!scsi_eh_get_sense(&eh_work_q, &eh_done_q)) | |
1512 | if (!scsi_eh_abort_cmds(&eh_work_q, &eh_done_q)) | |
1513 | scsi_eh_ready_devs(shost, &eh_work_q, &eh_done_q); | |
1514 | ||
1515 | scsi_eh_flush_done_q(&eh_done_q); | |
1516 | } | |
1517 | ||
1518 | /** | |
ad42eb1b | 1519 | * scsi_error_handler - SCSI error handler thread |
1da177e4 LT |
1520 | * @data: Host for which we are running. |
1521 | * | |
1522 | * Notes: | |
ad42eb1b CH |
1523 | * This is the main error handling loop. This is run as a kernel thread |
1524 | * for every SCSI host and handles all error handling activity. | |
1da177e4 LT |
1525 | **/ |
1526 | int scsi_error_handler(void *data) | |
1527 | { | |
ad42eb1b | 1528 | struct Scsi_Host *shost = data; |
1da177e4 | 1529 | |
1da177e4 | 1530 | current->flags |= PF_NOFREEZE; |
1da177e4 LT |
1531 | |
1532 | /* | |
ad42eb1b CH |
1533 | * We use TASK_INTERRUPTIBLE so that the thread is not |
1534 | * counted against the load average as a running process. | |
1535 | * We never actually get interrupted because kthread_run | |
1536 | * disables singal delivery for the created thread. | |
1da177e4 | 1537 | */ |
3ed7a470 JB |
1538 | set_current_state(TASK_INTERRUPTIBLE); |
1539 | while (!kthread_should_stop()) { | |
ee7863bc | 1540 | if ((shost->host_failed == 0 && shost->host_eh_scheduled == 0) || |
3ed7a470 | 1541 | shost->host_failed != shost->host_busy) { |
ad42eb1b CH |
1542 | SCSI_LOG_ERROR_RECOVERY(1, |
1543 | printk("Error handler scsi_eh_%d sleeping\n", | |
1544 | shost->host_no)); | |
3ed7a470 JB |
1545 | schedule(); |
1546 | set_current_state(TASK_INTERRUPTIBLE); | |
1547 | continue; | |
1548 | } | |
1da177e4 | 1549 | |
3ed7a470 | 1550 | __set_current_state(TASK_RUNNING); |
ad42eb1b CH |
1551 | SCSI_LOG_ERROR_RECOVERY(1, |
1552 | printk("Error handler scsi_eh_%d waking up\n", | |
1553 | shost->host_no)); | |
1da177e4 | 1554 | |
1da177e4 LT |
1555 | /* |
1556 | * We have a host that is failing for some reason. Figure out | |
1557 | * what we need to do to get it up and online again (if we can). | |
1558 | * If we fail, we end up taking the thing offline. | |
1559 | */ | |
9227c33d CH |
1560 | if (shost->transportt->eh_strategy_handler) |
1561 | shost->transportt->eh_strategy_handler(shost); | |
1da177e4 LT |
1562 | else |
1563 | scsi_unjam_host(shost); | |
1564 | ||
1da177e4 LT |
1565 | /* |
1566 | * Note - if the above fails completely, the action is to take | |
1567 | * individual devices offline and flush the queue of any | |
1568 | * outstanding requests that may have been pending. When we | |
1569 | * restart, we restart any I/O to any other devices on the bus | |
1570 | * which are still online. | |
1571 | */ | |
1572 | scsi_restart_operations(shost); | |
3ed7a470 | 1573 | set_current_state(TASK_INTERRUPTIBLE); |
1da177e4 | 1574 | } |
461a0ffb SR |
1575 | __set_current_state(TASK_RUNNING); |
1576 | ||
ad42eb1b CH |
1577 | SCSI_LOG_ERROR_RECOVERY(1, |
1578 | printk("Error handler scsi_eh_%d exiting\n", shost->host_no)); | |
3ed7a470 | 1579 | shost->ehandler = NULL; |
1da177e4 LT |
1580 | return 0; |
1581 | } | |
1582 | ||
1583 | /* | |
1584 | * Function: scsi_report_bus_reset() | |
1585 | * | |
1586 | * Purpose: Utility function used by low-level drivers to report that | |
1587 | * they have observed a bus reset on the bus being handled. | |
1588 | * | |
1589 | * Arguments: shost - Host in question | |
1590 | * channel - channel on which reset was observed. | |
1591 | * | |
1592 | * Returns: Nothing | |
1593 | * | |
1594 | * Lock status: Host lock must be held. | |
1595 | * | |
1596 | * Notes: This only needs to be called if the reset is one which | |
1597 | * originates from an unknown location. Resets originated | |
1598 | * by the mid-level itself don't need to call this, but there | |
1599 | * should be no harm. | |
1600 | * | |
1601 | * The main purpose of this is to make sure that a CHECK_CONDITION | |
1602 | * is properly treated. | |
1603 | */ | |
1604 | void scsi_report_bus_reset(struct Scsi_Host *shost, int channel) | |
1605 | { | |
1606 | struct scsi_device *sdev; | |
1607 | ||
1608 | __shost_for_each_device(sdev, shost) { | |
422c0d61 | 1609 | if (channel == sdev_channel(sdev)) { |
1da177e4 LT |
1610 | sdev->was_reset = 1; |
1611 | sdev->expecting_cc_ua = 1; | |
1612 | } | |
1613 | } | |
1614 | } | |
1615 | EXPORT_SYMBOL(scsi_report_bus_reset); | |
1616 | ||
1617 | /* | |
1618 | * Function: scsi_report_device_reset() | |
1619 | * | |
1620 | * Purpose: Utility function used by low-level drivers to report that | |
1621 | * they have observed a device reset on the device being handled. | |
1622 | * | |
1623 | * Arguments: shost - Host in question | |
1624 | * channel - channel on which reset was observed | |
1625 | * target - target on which reset was observed | |
1626 | * | |
1627 | * Returns: Nothing | |
1628 | * | |
1629 | * Lock status: Host lock must be held | |
1630 | * | |
1631 | * Notes: This only needs to be called if the reset is one which | |
1632 | * originates from an unknown location. Resets originated | |
1633 | * by the mid-level itself don't need to call this, but there | |
1634 | * should be no harm. | |
1635 | * | |
1636 | * The main purpose of this is to make sure that a CHECK_CONDITION | |
1637 | * is properly treated. | |
1638 | */ | |
1639 | void scsi_report_device_reset(struct Scsi_Host *shost, int channel, int target) | |
1640 | { | |
1641 | struct scsi_device *sdev; | |
1642 | ||
1643 | __shost_for_each_device(sdev, shost) { | |
422c0d61 JG |
1644 | if (channel == sdev_channel(sdev) && |
1645 | target == sdev_id(sdev)) { | |
1da177e4 LT |
1646 | sdev->was_reset = 1; |
1647 | sdev->expecting_cc_ua = 1; | |
1648 | } | |
1649 | } | |
1650 | } | |
1651 | EXPORT_SYMBOL(scsi_report_device_reset); | |
1652 | ||
1653 | static void | |
1654 | scsi_reset_provider_done_command(struct scsi_cmnd *scmd) | |
1655 | { | |
1656 | } | |
1657 | ||
1658 | /* | |
1659 | * Function: scsi_reset_provider | |
1660 | * | |
1661 | * Purpose: Send requested reset to a bus or device at any phase. | |
1662 | * | |
1663 | * Arguments: device - device to send reset to | |
1664 | * flag - reset type (see scsi.h) | |
1665 | * | |
1666 | * Returns: SUCCESS/FAILURE. | |
1667 | * | |
1668 | * Notes: This is used by the SCSI Generic driver to provide | |
1669 | * Bus/Device reset capability. | |
1670 | */ | |
1671 | int | |
1672 | scsi_reset_provider(struct scsi_device *dev, int flag) | |
1673 | { | |
1674 | struct scsi_cmnd *scmd = scsi_get_command(dev, GFP_KERNEL); | |
1675 | struct request req; | |
1676 | int rtn; | |
1677 | ||
1678 | scmd->request = &req; | |
1679 | memset(&scmd->eh_timeout, 0, sizeof(scmd->eh_timeout)); | |
b4edcbca | 1680 | |
1da177e4 LT |
1681 | memset(&scmd->cmnd, '\0', sizeof(scmd->cmnd)); |
1682 | ||
1683 | scmd->scsi_done = scsi_reset_provider_done_command; | |
1684 | scmd->done = NULL; | |
1685 | scmd->buffer = NULL; | |
1686 | scmd->bufflen = 0; | |
1687 | scmd->request_buffer = NULL; | |
1688 | scmd->request_bufflen = 0; | |
1da177e4 LT |
1689 | |
1690 | scmd->cmd_len = 0; | |
1691 | ||
1692 | scmd->sc_data_direction = DMA_BIDIRECTIONAL; | |
1da177e4 LT |
1693 | |
1694 | init_timer(&scmd->eh_timeout); | |
1695 | ||
1696 | /* | |
1697 | * Sometimes the command can get back into the timer chain, | |
1698 | * so use the pid as an identifier. | |
1699 | */ | |
1700 | scmd->pid = 0; | |
1701 | ||
1702 | switch (flag) { | |
1703 | case SCSI_TRY_RESET_DEVICE: | |
1704 | rtn = scsi_try_bus_device_reset(scmd); | |
1705 | if (rtn == SUCCESS) | |
1706 | break; | |
1707 | /* FALLTHROUGH */ | |
1708 | case SCSI_TRY_RESET_BUS: | |
1709 | rtn = scsi_try_bus_reset(scmd); | |
1710 | if (rtn == SUCCESS) | |
1711 | break; | |
1712 | /* FALLTHROUGH */ | |
1713 | case SCSI_TRY_RESET_HOST: | |
1714 | rtn = scsi_try_host_reset(scmd); | |
1715 | break; | |
1716 | default: | |
1717 | rtn = FAILED; | |
1718 | } | |
1719 | ||
1da177e4 LT |
1720 | scsi_next_command(scmd); |
1721 | return rtn; | |
1722 | } | |
1723 | EXPORT_SYMBOL(scsi_reset_provider); | |
1724 | ||
1725 | /** | |
1726 | * scsi_normalize_sense - normalize main elements from either fixed or | |
1727 | * descriptor sense data format into a common format. | |
1728 | * | |
1729 | * @sense_buffer: byte array containing sense data returned by device | |
1730 | * @sb_len: number of valid bytes in sense_buffer | |
1731 | * @sshdr: pointer to instance of structure that common | |
1732 | * elements are written to. | |
1733 | * | |
1734 | * Notes: | |
1735 | * The "main elements" from sense data are: response_code, sense_key, | |
1736 | * asc, ascq and additional_length (only for descriptor format). | |
1737 | * | |
1738 | * Typically this function can be called after a device has | |
1739 | * responded to a SCSI command with the CHECK_CONDITION status. | |
1740 | * | |
1741 | * Return value: | |
1742 | * 1 if valid sense data information found, else 0; | |
1743 | **/ | |
1744 | int scsi_normalize_sense(const u8 *sense_buffer, int sb_len, | |
1745 | struct scsi_sense_hdr *sshdr) | |
1746 | { | |
33aa687d | 1747 | if (!sense_buffer || !sb_len) |
1da177e4 LT |
1748 | return 0; |
1749 | ||
1750 | memset(sshdr, 0, sizeof(struct scsi_sense_hdr)); | |
1751 | ||
1752 | sshdr->response_code = (sense_buffer[0] & 0x7f); | |
33aa687d JB |
1753 | |
1754 | if (!scsi_sense_valid(sshdr)) | |
1755 | return 0; | |
1756 | ||
1da177e4 LT |
1757 | if (sshdr->response_code >= 0x72) { |
1758 | /* | |
1759 | * descriptor format | |
1760 | */ | |
1761 | if (sb_len > 1) | |
1762 | sshdr->sense_key = (sense_buffer[1] & 0xf); | |
1763 | if (sb_len > 2) | |
1764 | sshdr->asc = sense_buffer[2]; | |
1765 | if (sb_len > 3) | |
1766 | sshdr->ascq = sense_buffer[3]; | |
1767 | if (sb_len > 7) | |
1768 | sshdr->additional_length = sense_buffer[7]; | |
1769 | } else { | |
1770 | /* | |
1771 | * fixed format | |
1772 | */ | |
1773 | if (sb_len > 2) | |
1774 | sshdr->sense_key = (sense_buffer[2] & 0xf); | |
1775 | if (sb_len > 7) { | |
1776 | sb_len = (sb_len < (sense_buffer[7] + 8)) ? | |
1777 | sb_len : (sense_buffer[7] + 8); | |
1778 | if (sb_len > 12) | |
1779 | sshdr->asc = sense_buffer[12]; | |
1780 | if (sb_len > 13) | |
1781 | sshdr->ascq = sense_buffer[13]; | |
1782 | } | |
1783 | } | |
1784 | ||
1785 | return 1; | |
1786 | } | |
1787 | EXPORT_SYMBOL(scsi_normalize_sense); | |
1788 | ||
1da177e4 LT |
1789 | int scsi_command_normalize_sense(struct scsi_cmnd *cmd, |
1790 | struct scsi_sense_hdr *sshdr) | |
1791 | { | |
1792 | return scsi_normalize_sense(cmd->sense_buffer, | |
1793 | sizeof(cmd->sense_buffer), sshdr); | |
1794 | } | |
1795 | EXPORT_SYMBOL(scsi_command_normalize_sense); | |
1796 | ||
1797 | /** | |
1798 | * scsi_sense_desc_find - search for a given descriptor type in | |
1799 | * descriptor sense data format. | |
1800 | * | |
1801 | * @sense_buffer: byte array of descriptor format sense data | |
1802 | * @sb_len: number of valid bytes in sense_buffer | |
1803 | * @desc_type: value of descriptor type to find | |
1804 | * (e.g. 0 -> information) | |
1805 | * | |
1806 | * Notes: | |
1807 | * only valid when sense data is in descriptor format | |
1808 | * | |
1809 | * Return value: | |
1810 | * pointer to start of (first) descriptor if found else NULL | |
1811 | **/ | |
1812 | const u8 * scsi_sense_desc_find(const u8 * sense_buffer, int sb_len, | |
1813 | int desc_type) | |
1814 | { | |
1815 | int add_sen_len, add_len, desc_len, k; | |
1816 | const u8 * descp; | |
1817 | ||
1818 | if ((sb_len < 8) || (0 == (add_sen_len = sense_buffer[7]))) | |
1819 | return NULL; | |
1820 | if ((sense_buffer[0] < 0x72) || (sense_buffer[0] > 0x73)) | |
1821 | return NULL; | |
1822 | add_sen_len = (add_sen_len < (sb_len - 8)) ? | |
1823 | add_sen_len : (sb_len - 8); | |
1824 | descp = &sense_buffer[8]; | |
1825 | for (desc_len = 0, k = 0; k < add_sen_len; k += desc_len) { | |
1826 | descp += desc_len; | |
1827 | add_len = (k < (add_sen_len - 1)) ? descp[1]: -1; | |
1828 | desc_len = add_len + 2; | |
1829 | if (descp[0] == desc_type) | |
1830 | return descp; | |
1831 | if (add_len < 0) // short descriptor ?? | |
1832 | break; | |
1833 | } | |
1834 | return NULL; | |
1835 | } | |
1836 | EXPORT_SYMBOL(scsi_sense_desc_find); | |
1837 | ||
1838 | /** | |
1839 | * scsi_get_sense_info_fld - attempts to get information field from | |
1840 | * sense data (either fixed or descriptor format) | |
1841 | * | |
1842 | * @sense_buffer: byte array of sense data | |
1843 | * @sb_len: number of valid bytes in sense_buffer | |
1844 | * @info_out: pointer to 64 integer where 8 or 4 byte information | |
1845 | * field will be placed if found. | |
1846 | * | |
1847 | * Return value: | |
1848 | * 1 if information field found, 0 if not found. | |
1849 | **/ | |
1850 | int scsi_get_sense_info_fld(const u8 * sense_buffer, int sb_len, | |
1851 | u64 * info_out) | |
1852 | { | |
1853 | int j; | |
1854 | const u8 * ucp; | |
1855 | u64 ull; | |
1856 | ||
1857 | if (sb_len < 7) | |
1858 | return 0; | |
1859 | switch (sense_buffer[0] & 0x7f) { | |
1860 | case 0x70: | |
1861 | case 0x71: | |
1862 | if (sense_buffer[0] & 0x80) { | |
1863 | *info_out = (sense_buffer[3] << 24) + | |
1864 | (sense_buffer[4] << 16) + | |
1865 | (sense_buffer[5] << 8) + sense_buffer[6]; | |
1866 | return 1; | |
1867 | } else | |
1868 | return 0; | |
1869 | case 0x72: | |
1870 | case 0x73: | |
1871 | ucp = scsi_sense_desc_find(sense_buffer, sb_len, | |
1872 | 0 /* info desc */); | |
1873 | if (ucp && (0xa == ucp[1])) { | |
1874 | ull = 0; | |
1875 | for (j = 0; j < 8; ++j) { | |
1876 | if (j > 0) | |
1877 | ull <<= 8; | |
1878 | ull |= ucp[4 + j]; | |
1879 | } | |
1880 | *info_out = ull; | |
1881 | return 1; | |
1882 | } else | |
1883 | return 0; | |
1884 | default: | |
1885 | return 0; | |
1886 | } | |
1887 | } | |
1888 | EXPORT_SYMBOL(scsi_get_sense_info_fld); |