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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> | |
1da177e4 | 21 | #include <linux/kernel.h> |
83144186 | 22 | #include <linux/freezer.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" | |
79ee8304 | 39 | #include "scsi_transport_api.h" |
1da177e4 LT |
40 | |
41 | #define SENSE_TIMEOUT (10*HZ) | |
1da177e4 LT |
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. | |
dc8875e1 | 65 | */ |
f8bbfc24 TH |
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. | |
dc8875e1 | 89 | */ |
1da177e4 LT |
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. | |
dc8875e1 | 124 | */ |
1da177e4 LT |
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. | |
dc8875e1 | 158 | */ |
1da177e4 LT |
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. | |
dc8875e1 | 184 | */ |
1da177e4 LT |
185 | void scsi_times_out(struct scsi_cmnd *scmd) |
186 | { | |
6c5f8ce1 JB |
187 | enum scsi_eh_timer_return (* eh_timed_out)(struct scsi_cmnd *); |
188 | ||
1da177e4 LT |
189 | scsi_log_completion(scmd, TIMEOUT_ERROR); |
190 | ||
c829c394 | 191 | if (scmd->device->host->transportt->eh_timed_out) |
6c5f8ce1 JB |
192 | eh_timed_out = scmd->device->host->transportt->eh_timed_out; |
193 | else if (scmd->device->host->hostt->eh_timed_out) | |
194 | eh_timed_out = scmd->device->host->hostt->eh_timed_out; | |
195 | else | |
196 | eh_timed_out = NULL; | |
197 | ||
198 | if (eh_timed_out) | |
199 | switch (eh_timed_out(scmd)) { | |
1da177e4 LT |
200 | case EH_HANDLED: |
201 | __scsi_done(scmd); | |
202 | return; | |
203 | case EH_RESET_TIMER: | |
1da177e4 LT |
204 | scsi_add_timer(scmd, scmd->timeout_per_command, |
205 | scsi_times_out); | |
206 | return; | |
207 | case EH_NOT_HANDLED: | |
208 | break; | |
209 | } | |
210 | ||
211 | if (unlikely(!scsi_eh_scmd_add(scmd, SCSI_EH_CANCEL_CMD))) { | |
939647ee JB |
212 | scmd->result |= DID_TIME_OUT << 16; |
213 | __scsi_done(scmd); | |
1da177e4 LT |
214 | } |
215 | } | |
216 | ||
217 | /** | |
218 | * scsi_block_when_processing_errors - Prevent cmds from being queued. | |
219 | * @sdev: Device on which we are performing recovery. | |
220 | * | |
221 | * Description: | |
222 | * We block until the host is out of error recovery, and then check to | |
223 | * see whether the host or the device is offline. | |
224 | * | |
225 | * Return value: | |
226 | * 0 when dev was taken offline by error recovery. 1 OK to proceed. | |
dc8875e1 | 227 | */ |
1da177e4 LT |
228 | int scsi_block_when_processing_errors(struct scsi_device *sdev) |
229 | { | |
230 | int online; | |
231 | ||
939647ee | 232 | wait_event(sdev->host->host_wait, !scsi_host_in_recovery(sdev->host)); |
1da177e4 LT |
233 | |
234 | online = scsi_device_online(sdev); | |
235 | ||
236 | SCSI_LOG_ERROR_RECOVERY(5, printk("%s: rtn: %d\n", __FUNCTION__, | |
237 | online)); | |
238 | ||
239 | return online; | |
240 | } | |
241 | EXPORT_SYMBOL(scsi_block_when_processing_errors); | |
242 | ||
243 | #ifdef CONFIG_SCSI_LOGGING | |
244 | /** | |
245 | * scsi_eh_prt_fail_stats - Log info on failures. | |
246 | * @shost: scsi host being recovered. | |
247 | * @work_q: Queue of scsi cmds to process. | |
dc8875e1 | 248 | */ |
1da177e4 LT |
249 | static inline void scsi_eh_prt_fail_stats(struct Scsi_Host *shost, |
250 | struct list_head *work_q) | |
251 | { | |
252 | struct scsi_cmnd *scmd; | |
253 | struct scsi_device *sdev; | |
254 | int total_failures = 0; | |
255 | int cmd_failed = 0; | |
256 | int cmd_cancel = 0; | |
257 | int devices_failed = 0; | |
258 | ||
259 | shost_for_each_device(sdev, shost) { | |
260 | list_for_each_entry(scmd, work_q, eh_entry) { | |
261 | if (scmd->device == sdev) { | |
262 | ++total_failures; | |
3111b0d1 | 263 | if (scmd->eh_eflags & SCSI_EH_CANCEL_CMD) |
1da177e4 LT |
264 | ++cmd_cancel; |
265 | else | |
266 | ++cmd_failed; | |
267 | } | |
268 | } | |
269 | ||
270 | if (cmd_cancel || cmd_failed) { | |
271 | SCSI_LOG_ERROR_RECOVERY(3, | |
9ccfc756 JB |
272 | sdev_printk(KERN_INFO, sdev, |
273 | "%s: cmds failed: %d, cancel: %d\n", | |
274 | __FUNCTION__, cmd_failed, | |
275 | cmd_cancel)); | |
1da177e4 LT |
276 | cmd_cancel = 0; |
277 | cmd_failed = 0; | |
278 | ++devices_failed; | |
279 | } | |
280 | } | |
281 | ||
282 | SCSI_LOG_ERROR_RECOVERY(2, printk("Total of %d commands on %d" | |
283 | " devices require eh work\n", | |
284 | total_failures, devices_failed)); | |
285 | } | |
286 | #endif | |
287 | ||
288 | /** | |
289 | * scsi_check_sense - Examine scsi cmd sense | |
290 | * @scmd: Cmd to have sense checked. | |
291 | * | |
292 | * Return value: | |
293 | * SUCCESS or FAILED or NEEDS_RETRY | |
294 | * | |
295 | * Notes: | |
296 | * When a deferred error is detected the current command has | |
297 | * not been executed and needs retrying. | |
dc8875e1 | 298 | */ |
1da177e4 LT |
299 | static int scsi_check_sense(struct scsi_cmnd *scmd) |
300 | { | |
a6a8d9f8 | 301 | struct scsi_device *sdev = scmd->device; |
1da177e4 LT |
302 | struct scsi_sense_hdr sshdr; |
303 | ||
304 | if (! scsi_command_normalize_sense(scmd, &sshdr)) | |
305 | return FAILED; /* no valid sense data */ | |
306 | ||
307 | if (scsi_sense_is_deferred(&sshdr)) | |
308 | return NEEDS_RETRY; | |
309 | ||
a6a8d9f8 CS |
310 | if (sdev->scsi_dh_data && sdev->scsi_dh_data->scsi_dh && |
311 | sdev->scsi_dh_data->scsi_dh->check_sense) { | |
312 | int rc; | |
313 | ||
314 | rc = sdev->scsi_dh_data->scsi_dh->check_sense(sdev, &sshdr); | |
315 | if (rc != SCSI_RETURN_NOT_HANDLED) | |
316 | return rc; | |
317 | /* handler does not care. Drop down to default handling */ | |
318 | } | |
319 | ||
1da177e4 LT |
320 | /* |
321 | * Previous logic looked for FILEMARK, EOM or ILI which are | |
322 | * mainly associated with tapes and returned SUCCESS. | |
323 | */ | |
324 | if (sshdr.response_code == 0x70) { | |
325 | /* fixed format */ | |
326 | if (scmd->sense_buffer[2] & 0xe0) | |
327 | return SUCCESS; | |
328 | } else { | |
329 | /* | |
330 | * descriptor format: look for "stream commands sense data | |
331 | * descriptor" (see SSC-3). Assume single sense data | |
332 | * descriptor. Ignore ILI from SBC-2 READ LONG and WRITE LONG. | |
333 | */ | |
334 | if ((sshdr.additional_length > 3) && | |
335 | (scmd->sense_buffer[8] == 0x4) && | |
336 | (scmd->sense_buffer[11] & 0xe0)) | |
337 | return SUCCESS; | |
338 | } | |
339 | ||
340 | switch (sshdr.sense_key) { | |
341 | case NO_SENSE: | |
342 | return SUCCESS; | |
343 | case RECOVERED_ERROR: | |
344 | return /* soft_error */ SUCCESS; | |
345 | ||
346 | case ABORTED_COMMAND: | |
347 | return NEEDS_RETRY; | |
348 | case NOT_READY: | |
349 | case UNIT_ATTENTION: | |
350 | /* | |
351 | * if we are expecting a cc/ua because of a bus reset that we | |
352 | * performed, treat this just as a retry. otherwise this is | |
353 | * information that we should pass up to the upper-level driver | |
354 | * so that we can deal with it there. | |
355 | */ | |
356 | if (scmd->device->expecting_cc_ua) { | |
357 | scmd->device->expecting_cc_ua = 0; | |
358 | return NEEDS_RETRY; | |
359 | } | |
360 | /* | |
361 | * if the device is in the process of becoming ready, we | |
362 | * should retry. | |
363 | */ | |
364 | if ((sshdr.asc == 0x04) && (sshdr.ascq == 0x01)) | |
365 | return NEEDS_RETRY; | |
366 | /* | |
367 | * if the device is not started, we need to wake | |
368 | * the error handler to start the motor | |
369 | */ | |
370 | if (scmd->device->allow_restart && | |
371 | (sshdr.asc == 0x04) && (sshdr.ascq == 0x02)) | |
372 | return FAILED; | |
373 | return SUCCESS; | |
374 | ||
375 | /* these three are not supported */ | |
376 | case COPY_ABORTED: | |
377 | case VOLUME_OVERFLOW: | |
378 | case MISCOMPARE: | |
379 | return SUCCESS; | |
380 | ||
381 | case MEDIUM_ERROR: | |
fd1b494d LT |
382 | if (sshdr.asc == 0x11 || /* UNRECOVERED READ ERR */ |
383 | sshdr.asc == 0x13 || /* AMNF DATA FIELD */ | |
384 | sshdr.asc == 0x14) { /* RECORD NOT FOUND */ | |
385 | return SUCCESS; | |
386 | } | |
1da177e4 LT |
387 | return NEEDS_RETRY; |
388 | ||
389 | case HARDWARE_ERROR: | |
390 | if (scmd->device->retry_hwerror) | |
391 | return NEEDS_RETRY; | |
392 | else | |
393 | return SUCCESS; | |
394 | ||
395 | case ILLEGAL_REQUEST: | |
396 | case BLANK_CHECK: | |
397 | case DATA_PROTECT: | |
398 | default: | |
399 | return SUCCESS; | |
400 | } | |
401 | } | |
402 | ||
403 | /** | |
404 | * scsi_eh_completed_normally - Disposition a eh cmd on return from LLD. | |
405 | * @scmd: SCSI cmd to examine. | |
406 | * | |
407 | * Notes: | |
408 | * This is *only* called when we are examining the status of commands | |
409 | * queued during error recovery. the main difference here is that we | |
410 | * don't allow for the possibility of retries here, and we are a lot | |
411 | * more restrictive about what we consider acceptable. | |
dc8875e1 | 412 | */ |
1da177e4 LT |
413 | static int scsi_eh_completed_normally(struct scsi_cmnd *scmd) |
414 | { | |
415 | /* | |
416 | * first check the host byte, to see if there is anything in there | |
417 | * that would indicate what we need to do. | |
418 | */ | |
419 | if (host_byte(scmd->result) == DID_RESET) { | |
420 | /* | |
421 | * rats. we are already in the error handler, so we now | |
422 | * get to try and figure out what to do next. if the sense | |
423 | * is valid, we have a pretty good idea of what to do. | |
424 | * if not, we mark it as FAILED. | |
425 | */ | |
426 | return scsi_check_sense(scmd); | |
427 | } | |
428 | if (host_byte(scmd->result) != DID_OK) | |
429 | return FAILED; | |
430 | ||
431 | /* | |
432 | * next, check the message byte. | |
433 | */ | |
434 | if (msg_byte(scmd->result) != COMMAND_COMPLETE) | |
435 | return FAILED; | |
436 | ||
437 | /* | |
438 | * now, check the status byte to see if this indicates | |
439 | * anything special. | |
440 | */ | |
441 | switch (status_byte(scmd->result)) { | |
442 | case GOOD: | |
443 | case COMMAND_TERMINATED: | |
444 | return SUCCESS; | |
445 | case CHECK_CONDITION: | |
446 | return scsi_check_sense(scmd); | |
447 | case CONDITION_GOOD: | |
448 | case INTERMEDIATE_GOOD: | |
449 | case INTERMEDIATE_C_GOOD: | |
450 | /* | |
451 | * who knows? FIXME(eric) | |
452 | */ | |
453 | return SUCCESS; | |
454 | case BUSY: | |
455 | case QUEUE_FULL: | |
456 | case RESERVATION_CONFLICT: | |
457 | default: | |
458 | return FAILED; | |
459 | } | |
460 | return FAILED; | |
461 | } | |
462 | ||
1da177e4 LT |
463 | /** |
464 | * scsi_eh_done - Completion function for error handling. | |
465 | * @scmd: Cmd that is done. | |
dc8875e1 | 466 | */ |
1da177e4 LT |
467 | static void scsi_eh_done(struct scsi_cmnd *scmd) |
468 | { | |
85631672 MR |
469 | struct completion *eh_action; |
470 | ||
7dfdc9a5 CH |
471 | SCSI_LOG_ERROR_RECOVERY(3, |
472 | printk("%s scmd: %p result: %x\n", | |
473 | __FUNCTION__, scmd, scmd->result)); | |
85631672 MR |
474 | |
475 | eh_action = scmd->device->host->eh_action; | |
476 | if (eh_action) | |
477 | complete(eh_action); | |
1da177e4 LT |
478 | } |
479 | ||
292148f8 BK |
480 | /** |
481 | * scsi_try_host_reset - ask host adapter to reset itself | |
482 | * @scmd: SCSI cmd to send hsot reset. | |
dc8875e1 | 483 | */ |
292148f8 BK |
484 | static int scsi_try_host_reset(struct scsi_cmnd *scmd) |
485 | { | |
486 | unsigned long flags; | |
487 | int rtn; | |
488 | ||
489 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Snd Host RST\n", | |
490 | __FUNCTION__)); | |
491 | ||
492 | if (!scmd->device->host->hostt->eh_host_reset_handler) | |
493 | return FAILED; | |
494 | ||
495 | rtn = scmd->device->host->hostt->eh_host_reset_handler(scmd); | |
496 | ||
497 | if (rtn == SUCCESS) { | |
498 | if (!scmd->device->host->hostt->skip_settle_delay) | |
499 | ssleep(HOST_RESET_SETTLE_TIME); | |
500 | spin_lock_irqsave(scmd->device->host->host_lock, flags); | |
501 | scsi_report_bus_reset(scmd->device->host, | |
502 | scmd_channel(scmd)); | |
503 | spin_unlock_irqrestore(scmd->device->host->host_lock, flags); | |
504 | } | |
505 | ||
506 | return rtn; | |
507 | } | |
508 | ||
509 | /** | |
510 | * scsi_try_bus_reset - ask host to perform a bus reset | |
511 | * @scmd: SCSI cmd to send bus reset. | |
dc8875e1 | 512 | */ |
292148f8 BK |
513 | static int scsi_try_bus_reset(struct scsi_cmnd *scmd) |
514 | { | |
515 | unsigned long flags; | |
516 | int rtn; | |
517 | ||
518 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Snd Bus RST\n", | |
519 | __FUNCTION__)); | |
520 | ||
521 | if (!scmd->device->host->hostt->eh_bus_reset_handler) | |
522 | return FAILED; | |
523 | ||
524 | rtn = scmd->device->host->hostt->eh_bus_reset_handler(scmd); | |
525 | ||
526 | if (rtn == SUCCESS) { | |
527 | if (!scmd->device->host->hostt->skip_settle_delay) | |
528 | ssleep(BUS_RESET_SETTLE_TIME); | |
529 | spin_lock_irqsave(scmd->device->host->host_lock, flags); | |
530 | scsi_report_bus_reset(scmd->device->host, | |
531 | scmd_channel(scmd)); | |
532 | spin_unlock_irqrestore(scmd->device->host->host_lock, flags); | |
533 | } | |
534 | ||
535 | return rtn; | |
536 | } | |
537 | ||
30bd7df8 MC |
538 | static void __scsi_report_device_reset(struct scsi_device *sdev, void *data) |
539 | { | |
540 | sdev->was_reset = 1; | |
541 | sdev->expecting_cc_ua = 1; | |
542 | } | |
543 | ||
544 | /** | |
545 | * scsi_try_target_reset - Ask host to perform a target reset | |
546 | * @scmd: SCSI cmd used to send a target reset | |
547 | * | |
548 | * Notes: | |
549 | * There is no timeout for this operation. if this operation is | |
550 | * unreliable for a given host, then the host itself needs to put a | |
551 | * timer on it, and set the host back to a consistent state prior to | |
552 | * returning. | |
553 | */ | |
554 | static int scsi_try_target_reset(struct scsi_cmnd *scmd) | |
555 | { | |
556 | unsigned long flags; | |
557 | int rtn; | |
558 | ||
559 | if (!scmd->device->host->hostt->eh_target_reset_handler) | |
560 | return FAILED; | |
561 | ||
562 | rtn = scmd->device->host->hostt->eh_target_reset_handler(scmd); | |
563 | if (rtn == SUCCESS) { | |
564 | spin_lock_irqsave(scmd->device->host->host_lock, flags); | |
565 | __starget_for_each_device(scsi_target(scmd->device), NULL, | |
566 | __scsi_report_device_reset); | |
567 | spin_unlock_irqrestore(scmd->device->host->host_lock, flags); | |
568 | } | |
569 | ||
570 | return rtn; | |
571 | } | |
572 | ||
292148f8 BK |
573 | /** |
574 | * scsi_try_bus_device_reset - Ask host to perform a BDR on a dev | |
575 | * @scmd: SCSI cmd used to send BDR | |
576 | * | |
577 | * Notes: | |
578 | * There is no timeout for this operation. if this operation is | |
579 | * unreliable for a given host, then the host itself needs to put a | |
580 | * timer on it, and set the host back to a consistent state prior to | |
581 | * returning. | |
dc8875e1 | 582 | */ |
292148f8 BK |
583 | static int scsi_try_bus_device_reset(struct scsi_cmnd *scmd) |
584 | { | |
585 | int rtn; | |
586 | ||
587 | if (!scmd->device->host->hostt->eh_device_reset_handler) | |
588 | return FAILED; | |
589 | ||
590 | rtn = scmd->device->host->hostt->eh_device_reset_handler(scmd); | |
30bd7df8 MC |
591 | if (rtn == SUCCESS) |
592 | __scsi_report_device_reset(scmd->device, NULL); | |
292148f8 BK |
593 | return rtn; |
594 | } | |
595 | ||
596 | static int __scsi_try_to_abort_cmd(struct scsi_cmnd *scmd) | |
597 | { | |
598 | if (!scmd->device->host->hostt->eh_abort_handler) | |
599 | return FAILED; | |
600 | ||
601 | return scmd->device->host->hostt->eh_abort_handler(scmd); | |
602 | } | |
603 | ||
604 | /** | |
605 | * scsi_try_to_abort_cmd - Ask host to abort a running command. | |
606 | * @scmd: SCSI cmd to abort from Lower Level. | |
607 | * | |
608 | * Notes: | |
609 | * This function will not return until the user's completion function | |
610 | * has been called. there is no timeout on this operation. if the | |
611 | * author of the low-level driver wishes this operation to be timed, | |
612 | * they can provide this facility themselves. helper functions in | |
613 | * scsi_error.c can be supplied to make this easier to do. | |
dc8875e1 | 614 | */ |
292148f8 BK |
615 | static int scsi_try_to_abort_cmd(struct scsi_cmnd *scmd) |
616 | { | |
617 | /* | |
618 | * scsi_done was called just after the command timed out and before | |
619 | * we had a chance to process it. (db) | |
620 | */ | |
621 | if (scmd->serial_number == 0) | |
622 | return SUCCESS; | |
623 | return __scsi_try_to_abort_cmd(scmd); | |
624 | } | |
625 | ||
626 | static void scsi_abort_eh_cmnd(struct scsi_cmnd *scmd) | |
627 | { | |
628 | if (__scsi_try_to_abort_cmd(scmd) != SUCCESS) | |
629 | if (scsi_try_bus_device_reset(scmd) != SUCCESS) | |
30bd7df8 MC |
630 | if (scsi_try_target_reset(scmd) != SUCCESS) |
631 | if (scsi_try_bus_reset(scmd) != SUCCESS) | |
632 | scsi_try_host_reset(scmd); | |
292148f8 BK |
633 | } |
634 | ||
1da177e4 | 635 | /** |
e1c23468 | 636 | * scsi_eh_prep_cmnd - Save a scsi command info as part of error recory |
2dc611de | 637 | * @scmd: SCSI command structure to hijack |
e1c23468 | 638 | * @ses: structure to save restore information |
55db6c1b | 639 | * @cmnd: CDB to send. Can be NULL if no new cmnd is needed |
64a87b24 | 640 | * @cmnd_size: size in bytes of @cmnd (must be <= BLK_MAX_CDB) |
55db6c1b | 641 | * @sense_bytes: size of sense data to copy. or 0 (if != 0 @cmnd is ignored) |
2dc611de | 642 | * |
e1c23468 | 643 | * This function is used to save a scsi command information before re-execution |
55db6c1b BH |
644 | * as part of the error recovery process. If @sense_bytes is 0 the command |
645 | * sent must be one that does not transfer any data. If @sense_bytes != 0 | |
646 | * @cmnd is ignored and this functions sets up a REQUEST_SENSE command | |
647 | * and cmnd buffers to read @sense_bytes into @scmd->sense_buffer. | |
dc8875e1 | 648 | */ |
e1c23468 BH |
649 | void scsi_eh_prep_cmnd(struct scsi_cmnd *scmd, struct scsi_eh_save *ses, |
650 | unsigned char *cmnd, int cmnd_size, unsigned sense_bytes) | |
1da177e4 | 651 | { |
f59114b7 | 652 | struct scsi_device *sdev = scmd->device; |
1da177e4 | 653 | |
631c228c CH |
654 | /* |
655 | * We need saved copies of a number of fields - this is because | |
656 | * error handling may need to overwrite these with different values | |
657 | * to run different commands, and once error handling is complete, | |
658 | * we will need to restore these values prior to running the actual | |
659 | * command. | |
660 | */ | |
e1c23468 | 661 | ses->cmd_len = scmd->cmd_len; |
64a87b24 | 662 | ses->cmnd = scmd->cmnd; |
e1c23468 | 663 | ses->data_direction = scmd->sc_data_direction; |
30b0c37b | 664 | ses->sdb = scmd->sdb; |
6f9a35e2 | 665 | ses->next_rq = scmd->request->next_rq; |
e1c23468 | 666 | ses->result = scmd->result; |
631c228c | 667 | |
64a87b24 BH |
668 | scmd->cmnd = ses->eh_cmnd; |
669 | memset(scmd->cmnd, 0, BLK_MAX_CDB); | |
30b0c37b | 670 | memset(&scmd->sdb, 0, sizeof(scmd->sdb)); |
6f9a35e2 | 671 | scmd->request->next_rq = NULL; |
30b0c37b | 672 | |
55db6c1b | 673 | if (sense_bytes) { |
30b0c37b BH |
674 | scmd->sdb.length = min_t(unsigned, SCSI_SENSE_BUFFERSIZE, |
675 | sense_bytes); | |
e1c23468 | 676 | sg_init_one(&ses->sense_sgl, scmd->sense_buffer, |
30b0c37b BH |
677 | scmd->sdb.length); |
678 | scmd->sdb.table.sgl = &ses->sense_sgl; | |
55db6c1b | 679 | scmd->sc_data_direction = DMA_FROM_DEVICE; |
30b0c37b | 680 | scmd->sdb.table.nents = 1; |
55db6c1b | 681 | scmd->cmnd[0] = REQUEST_SENSE; |
30b0c37b | 682 | scmd->cmnd[4] = scmd->sdb.length; |
55db6c1b | 683 | scmd->cmd_len = COMMAND_SIZE(scmd->cmnd[0]); |
631c228c | 684 | } else { |
631c228c | 685 | scmd->sc_data_direction = DMA_NONE; |
55db6c1b | 686 | if (cmnd) { |
64a87b24 | 687 | BUG_ON(cmnd_size > BLK_MAX_CDB); |
55db6c1b BH |
688 | memcpy(scmd->cmnd, cmnd, cmnd_size); |
689 | scmd->cmd_len = COMMAND_SIZE(scmd->cmnd[0]); | |
690 | } | |
631c228c CH |
691 | } |
692 | ||
693 | scmd->underflow = 0; | |
631c228c | 694 | |
55db6c1b | 695 | if (sdev->scsi_level <= SCSI_2 && sdev->scsi_level != SCSI_UNKNOWN) |
1da177e4 | 696 | scmd->cmnd[1] = (scmd->cmnd[1] & 0x1f) | |
f59114b7 | 697 | (sdev->lun << 5 & 0xe0); |
1da177e4 | 698 | |
631c228c CH |
699 | /* |
700 | * Zero the sense buffer. The scsi spec mandates that any | |
701 | * untransferred sense data should be interpreted as being zero. | |
702 | */ | |
b80ca4f7 | 703 | memset(scmd->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE); |
e1c23468 BH |
704 | } |
705 | EXPORT_SYMBOL(scsi_eh_prep_cmnd); | |
706 | ||
707 | /** | |
708 | * scsi_eh_restore_cmnd - Restore a scsi command info as part of error recory | |
709 | * @scmd: SCSI command structure to restore | |
710 | * @ses: saved information from a coresponding call to scsi_prep_eh_cmnd | |
711 | * | |
712 | * Undo any damage done by above scsi_prep_eh_cmnd(). | |
dc8875e1 | 713 | */ |
e1c23468 BH |
714 | void scsi_eh_restore_cmnd(struct scsi_cmnd* scmd, struct scsi_eh_save *ses) |
715 | { | |
716 | /* | |
717 | * Restore original data | |
718 | */ | |
719 | scmd->cmd_len = ses->cmd_len; | |
64a87b24 | 720 | scmd->cmnd = ses->cmnd; |
e1c23468 | 721 | scmd->sc_data_direction = ses->data_direction; |
30b0c37b | 722 | scmd->sdb = ses->sdb; |
6f9a35e2 | 723 | scmd->request->next_rq = ses->next_rq; |
e1c23468 BH |
724 | scmd->result = ses->result; |
725 | } | |
726 | EXPORT_SYMBOL(scsi_eh_restore_cmnd); | |
631c228c | 727 | |
e1c23468 BH |
728 | /** |
729 | * scsi_send_eh_cmnd - submit a scsi command as part of error recory | |
730 | * @scmd: SCSI command structure to hijack | |
731 | * @cmnd: CDB to send | |
732 | * @cmnd_size: size in bytes of @cmnd | |
733 | * @timeout: timeout for this request | |
734 | * @sense_bytes: size of sense data to copy or 0 | |
735 | * | |
736 | * This function is used to send a scsi command down to a target device | |
737 | * as part of the error recovery process. See also scsi_eh_prep_cmnd() above. | |
738 | * | |
739 | * Return value: | |
740 | * SUCCESS or FAILED or NEEDS_RETRY | |
dc8875e1 | 741 | */ |
e1c23468 BH |
742 | static int scsi_send_eh_cmnd(struct scsi_cmnd *scmd, unsigned char *cmnd, |
743 | int cmnd_size, int timeout, unsigned sense_bytes) | |
744 | { | |
745 | struct scsi_device *sdev = scmd->device; | |
746 | struct Scsi_Host *shost = sdev->host; | |
747 | DECLARE_COMPLETION_ONSTACK(done); | |
748 | unsigned long timeleft; | |
749 | unsigned long flags; | |
750 | struct scsi_eh_save ses; | |
751 | int rtn; | |
752 | ||
753 | scsi_eh_prep_cmnd(scmd, &ses, cmnd, cmnd_size, sense_bytes); | |
7dfdc9a5 | 754 | shost->eh_action = &done; |
1da177e4 | 755 | |
f59114b7 | 756 | spin_lock_irqsave(shost->host_lock, flags); |
1da177e4 | 757 | scsi_log_send(scmd); |
f59114b7 TH |
758 | shost->hostt->queuecommand(scmd, scsi_eh_done); |
759 | spin_unlock_irqrestore(shost->host_lock, flags); | |
1da177e4 | 760 | |
7dfdc9a5 | 761 | timeleft = wait_for_completion_timeout(&done, timeout); |
1da177e4 | 762 | |
f59114b7 | 763 | shost->eh_action = NULL; |
1da177e4 | 764 | |
7dfdc9a5 | 765 | scsi_log_completion(scmd, SUCCESS); |
1da177e4 | 766 | |
7dfdc9a5 CH |
767 | SCSI_LOG_ERROR_RECOVERY(3, |
768 | printk("%s: scmd: %p, timeleft: %ld\n", | |
769 | __FUNCTION__, scmd, timeleft)); | |
1da177e4 LT |
770 | |
771 | /* | |
7dfdc9a5 CH |
772 | * If there is time left scsi_eh_done got called, and we will |
773 | * examine the actual status codes to see whether the command | |
774 | * actually did complete normally, else tell the host to forget | |
775 | * about this command. | |
1da177e4 | 776 | */ |
7dfdc9a5 | 777 | if (timeleft) { |
1da177e4 LT |
778 | rtn = scsi_eh_completed_normally(scmd); |
779 | SCSI_LOG_ERROR_RECOVERY(3, | |
780 | printk("%s: scsi_eh_completed_normally %x\n", | |
781 | __FUNCTION__, rtn)); | |
7dfdc9a5 | 782 | |
1da177e4 LT |
783 | switch (rtn) { |
784 | case SUCCESS: | |
785 | case NEEDS_RETRY: | |
786 | case FAILED: | |
787 | break; | |
788 | default: | |
789 | rtn = FAILED; | |
790 | break; | |
791 | } | |
7dfdc9a5 | 792 | } else { |
292148f8 | 793 | scsi_abort_eh_cmnd(scmd); |
7dfdc9a5 | 794 | rtn = FAILED; |
1da177e4 LT |
795 | } |
796 | ||
e1c23468 | 797 | scsi_eh_restore_cmnd(scmd, &ses); |
1da177e4 LT |
798 | return rtn; |
799 | } | |
800 | ||
801 | /** | |
802 | * scsi_request_sense - Request sense data from a particular target. | |
803 | * @scmd: SCSI cmd for request sense. | |
804 | * | |
805 | * Notes: | |
806 | * Some hosts automatically obtain this information, others require | |
807 | * that we obtain it on our own. This function will *not* return until | |
808 | * the command either times out, or it completes. | |
dc8875e1 | 809 | */ |
1da177e4 LT |
810 | static int scsi_request_sense(struct scsi_cmnd *scmd) |
811 | { | |
55db6c1b | 812 | return scsi_send_eh_cmnd(scmd, NULL, 0, SENSE_TIMEOUT, ~0); |
1da177e4 LT |
813 | } |
814 | ||
815 | /** | |
816 | * scsi_eh_finish_cmd - Handle a cmd that eh is finished with. | |
817 | * @scmd: Original SCSI cmd that eh has finished. | |
818 | * @done_q: Queue for processed commands. | |
819 | * | |
820 | * Notes: | |
821 | * We don't want to use the normal command completion while we are are | |
822 | * still handling errors - it may cause other commands to be queued, | |
eb44820c | 823 | * and that would disturb what we are doing. Thus we really want to |
1da177e4 LT |
824 | * keep a list of pending commands for final completion, and once we |
825 | * are ready to leave error handling we handle completion for real. | |
dc8875e1 | 826 | */ |
041c5fc3 | 827 | void scsi_eh_finish_cmd(struct scsi_cmnd *scmd, struct list_head *done_q) |
1da177e4 LT |
828 | { |
829 | scmd->device->host->host_failed--; | |
3111b0d1 | 830 | scmd->eh_eflags = 0; |
1da177e4 LT |
831 | list_move_tail(&scmd->eh_entry, done_q); |
832 | } | |
041c5fc3 | 833 | EXPORT_SYMBOL(scsi_eh_finish_cmd); |
1da177e4 LT |
834 | |
835 | /** | |
836 | * scsi_eh_get_sense - Get device sense data. | |
837 | * @work_q: Queue of commands to process. | |
eb44820c | 838 | * @done_q: Queue of processed commands. |
1da177e4 LT |
839 | * |
840 | * Description: | |
841 | * See if we need to request sense information. if so, then get it | |
842 | * now, so we have a better idea of what to do. | |
843 | * | |
844 | * Notes: | |
845 | * This has the unfortunate side effect that if a shost adapter does | |
eb44820c | 846 | * not automatically request sense information, we end up shutting |
1da177e4 LT |
847 | * it down before we request it. |
848 | * | |
849 | * All drivers should request sense information internally these days, | |
850 | * so for now all I have to say is tough noogies if you end up in here. | |
851 | * | |
852 | * XXX: Long term this code should go away, but that needs an audit of | |
853 | * all LLDDs first. | |
dc8875e1 | 854 | */ |
dca84e46 DW |
855 | int scsi_eh_get_sense(struct list_head *work_q, |
856 | struct list_head *done_q) | |
1da177e4 | 857 | { |
937abeaa | 858 | struct scsi_cmnd *scmd, *next; |
1da177e4 LT |
859 | int rtn; |
860 | ||
937abeaa | 861 | list_for_each_entry_safe(scmd, next, work_q, eh_entry) { |
3111b0d1 | 862 | if ((scmd->eh_eflags & SCSI_EH_CANCEL_CMD) || |
1da177e4 LT |
863 | SCSI_SENSE_VALID(scmd)) |
864 | continue; | |
865 | ||
3bf743e7 JG |
866 | SCSI_LOG_ERROR_RECOVERY(2, scmd_printk(KERN_INFO, scmd, |
867 | "%s: requesting sense\n", | |
868 | current->comm)); | |
1da177e4 LT |
869 | rtn = scsi_request_sense(scmd); |
870 | if (rtn != SUCCESS) | |
871 | continue; | |
872 | ||
873 | SCSI_LOG_ERROR_RECOVERY(3, printk("sense requested for %p" | |
874 | " result %x\n", scmd, | |
875 | scmd->result)); | |
876 | SCSI_LOG_ERROR_RECOVERY(3, scsi_print_sense("bh", scmd)); | |
877 | ||
878 | rtn = scsi_decide_disposition(scmd); | |
879 | ||
880 | /* | |
881 | * if the result was normal, then just pass it along to the | |
882 | * upper level. | |
883 | */ | |
884 | if (rtn == SUCCESS) | |
885 | /* we don't want this command reissued, just | |
886 | * finished with the sense data, so set | |
887 | * retries to the max allowed to ensure it | |
888 | * won't get reissued */ | |
889 | scmd->retries = scmd->allowed; | |
890 | else if (rtn != NEEDS_RETRY) | |
891 | continue; | |
892 | ||
893 | scsi_eh_finish_cmd(scmd, done_q); | |
894 | } | |
895 | ||
896 | return list_empty(work_q); | |
897 | } | |
dca84e46 | 898 | EXPORT_SYMBOL_GPL(scsi_eh_get_sense); |
1da177e4 | 899 | |
1da177e4 LT |
900 | /** |
901 | * scsi_eh_tur - Send TUR to device. | |
eb44820c | 902 | * @scmd: &scsi_cmnd to send TUR |
1da177e4 LT |
903 | * |
904 | * Return value: | |
905 | * 0 - Device is ready. 1 - Device NOT ready. | |
dc8875e1 | 906 | */ |
1da177e4 LT |
907 | static int scsi_eh_tur(struct scsi_cmnd *scmd) |
908 | { | |
909 | static unsigned char tur_command[6] = {TEST_UNIT_READY, 0, 0, 0, 0, 0}; | |
910 | int retry_cnt = 1, rtn; | |
911 | ||
912 | retry_tur: | |
0db99e33 | 913 | rtn = scsi_send_eh_cmnd(scmd, tur_command, 6, SENSE_TIMEOUT, 0); |
1da177e4 | 914 | |
1da177e4 LT |
915 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: scmd %p rtn %x\n", |
916 | __FUNCTION__, scmd, rtn)); | |
631c228c CH |
917 | |
918 | switch (rtn) { | |
919 | case NEEDS_RETRY: | |
1da177e4 LT |
920 | if (retry_cnt--) |
921 | goto retry_tur; | |
631c228c CH |
922 | /*FALLTHRU*/ |
923 | case SUCCESS: | |
e47373ec | 924 | return 0; |
631c228c CH |
925 | default: |
926 | return 1; | |
e47373ec | 927 | } |
1da177e4 LT |
928 | } |
929 | ||
930 | /** | |
eb44820c RL |
931 | * scsi_eh_abort_cmds - abort pending commands. |
932 | * @work_q: &list_head for pending commands. | |
933 | * @done_q: &list_head for processed commands. | |
1da177e4 LT |
934 | * |
935 | * Decription: | |
936 | * Try and see whether or not it makes sense to try and abort the | |
eb44820c RL |
937 | * running command. This only works out to be the case if we have one |
938 | * command that has timed out. If the command simply failed, it makes | |
1da177e4 LT |
939 | * no sense to try and abort the command, since as far as the shost |
940 | * adapter is concerned, it isn't running. | |
dc8875e1 | 941 | */ |
1da177e4 LT |
942 | static int scsi_eh_abort_cmds(struct list_head *work_q, |
943 | struct list_head *done_q) | |
944 | { | |
937abeaa | 945 | struct scsi_cmnd *scmd, *next; |
1da177e4 LT |
946 | int rtn; |
947 | ||
937abeaa | 948 | list_for_each_entry_safe(scmd, next, work_q, eh_entry) { |
3111b0d1 | 949 | if (!(scmd->eh_eflags & SCSI_EH_CANCEL_CMD)) |
1da177e4 LT |
950 | continue; |
951 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: aborting cmd:" | |
952 | "0x%p\n", current->comm, | |
953 | scmd)); | |
954 | rtn = scsi_try_to_abort_cmd(scmd); | |
955 | if (rtn == SUCCESS) { | |
3111b0d1 | 956 | scmd->eh_eflags &= ~SCSI_EH_CANCEL_CMD; |
1da177e4 LT |
957 | if (!scsi_device_online(scmd->device) || |
958 | !scsi_eh_tur(scmd)) { | |
959 | scsi_eh_finish_cmd(scmd, done_q); | |
960 | } | |
961 | ||
962 | } else | |
963 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: aborting" | |
964 | " cmd failed:" | |
965 | "0x%p\n", | |
966 | current->comm, | |
967 | scmd)); | |
968 | } | |
969 | ||
970 | return list_empty(work_q); | |
971 | } | |
972 | ||
1da177e4 LT |
973 | /** |
974 | * scsi_eh_try_stu - Send START_UNIT to device. | |
eb44820c | 975 | * @scmd: &scsi_cmnd to send START_UNIT |
1da177e4 LT |
976 | * |
977 | * Return value: | |
978 | * 0 - Device is ready. 1 - Device NOT ready. | |
dc8875e1 | 979 | */ |
1da177e4 LT |
980 | static int scsi_eh_try_stu(struct scsi_cmnd *scmd) |
981 | { | |
982 | static unsigned char stu_command[6] = {START_STOP, 0, 0, 0, 1, 0}; | |
1da177e4 | 983 | |
631c228c | 984 | if (scmd->device->allow_restart) { |
ed773e66 BK |
985 | int i, rtn = NEEDS_RETRY; |
986 | ||
987 | for (i = 0; rtn == NEEDS_RETRY && i < 2; i++) | |
988 | rtn = scsi_send_eh_cmnd(scmd, stu_command, 6, | |
e555db93 | 989 | scmd->device->timeout, 0); |
1da177e4 | 990 | |
631c228c CH |
991 | if (rtn == SUCCESS) |
992 | return 0; | |
993 | } | |
1da177e4 | 994 | |
1da177e4 LT |
995 | return 1; |
996 | } | |
997 | ||
998 | /** | |
999 | * scsi_eh_stu - send START_UNIT if needed | |
eb44820c RL |
1000 | * @shost: &scsi host being recovered. |
1001 | * @work_q: &list_head for pending commands. | |
1002 | * @done_q: &list_head for processed commands. | |
1da177e4 LT |
1003 | * |
1004 | * Notes: | |
1005 | * If commands are failing due to not ready, initializing command required, | |
1006 | * try revalidating the device, which will end up sending a start unit. | |
dc8875e1 | 1007 | */ |
1da177e4 LT |
1008 | static int scsi_eh_stu(struct Scsi_Host *shost, |
1009 | struct list_head *work_q, | |
1010 | struct list_head *done_q) | |
1011 | { | |
937abeaa | 1012 | struct scsi_cmnd *scmd, *stu_scmd, *next; |
1da177e4 LT |
1013 | struct scsi_device *sdev; |
1014 | ||
1015 | shost_for_each_device(sdev, shost) { | |
1016 | stu_scmd = NULL; | |
1017 | list_for_each_entry(scmd, work_q, eh_entry) | |
1018 | if (scmd->device == sdev && SCSI_SENSE_VALID(scmd) && | |
1019 | scsi_check_sense(scmd) == FAILED ) { | |
1020 | stu_scmd = scmd; | |
1021 | break; | |
1022 | } | |
1023 | ||
1024 | if (!stu_scmd) | |
1025 | continue; | |
1026 | ||
1027 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending START_UNIT to sdev:" | |
1028 | " 0x%p\n", current->comm, sdev)); | |
1029 | ||
1030 | if (!scsi_eh_try_stu(stu_scmd)) { | |
1031 | if (!scsi_device_online(sdev) || | |
1032 | !scsi_eh_tur(stu_scmd)) { | |
937abeaa CH |
1033 | list_for_each_entry_safe(scmd, next, |
1034 | work_q, eh_entry) { | |
1da177e4 LT |
1035 | if (scmd->device == sdev) |
1036 | scsi_eh_finish_cmd(scmd, done_q); | |
1037 | } | |
1038 | } | |
1039 | } else { | |
1040 | SCSI_LOG_ERROR_RECOVERY(3, | |
1041 | printk("%s: START_UNIT failed to sdev:" | |
1042 | " 0x%p\n", current->comm, sdev)); | |
1043 | } | |
1044 | } | |
1045 | ||
1046 | return list_empty(work_q); | |
1047 | } | |
1048 | ||
1049 | ||
1050 | /** | |
1051 | * scsi_eh_bus_device_reset - send bdr if needed | |
1052 | * @shost: scsi host being recovered. | |
eb44820c RL |
1053 | * @work_q: &list_head for pending commands. |
1054 | * @done_q: &list_head for processed commands. | |
1da177e4 LT |
1055 | * |
1056 | * Notes: | |
eb44820c | 1057 | * Try a bus device reset. Still, look to see whether we have multiple |
1da177e4 LT |
1058 | * devices that are jammed or not - if we have multiple devices, it |
1059 | * makes no sense to try bus_device_reset - we really would need to try | |
1060 | * a bus_reset instead. | |
dc8875e1 | 1061 | */ |
1da177e4 LT |
1062 | static int scsi_eh_bus_device_reset(struct Scsi_Host *shost, |
1063 | struct list_head *work_q, | |
1064 | struct list_head *done_q) | |
1065 | { | |
937abeaa | 1066 | struct scsi_cmnd *scmd, *bdr_scmd, *next; |
1da177e4 LT |
1067 | struct scsi_device *sdev; |
1068 | int rtn; | |
1069 | ||
1070 | shost_for_each_device(sdev, shost) { | |
1071 | bdr_scmd = NULL; | |
1072 | list_for_each_entry(scmd, work_q, eh_entry) | |
1073 | if (scmd->device == sdev) { | |
1074 | bdr_scmd = scmd; | |
1075 | break; | |
1076 | } | |
1077 | ||
1078 | if (!bdr_scmd) | |
1079 | continue; | |
1080 | ||
1081 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending BDR sdev:" | |
1082 | " 0x%p\n", current->comm, | |
1083 | sdev)); | |
1084 | rtn = scsi_try_bus_device_reset(bdr_scmd); | |
1085 | if (rtn == SUCCESS) { | |
1086 | if (!scsi_device_online(sdev) || | |
1087 | !scsi_eh_tur(bdr_scmd)) { | |
937abeaa CH |
1088 | list_for_each_entry_safe(scmd, next, |
1089 | work_q, eh_entry) { | |
1da177e4 LT |
1090 | if (scmd->device == sdev) |
1091 | scsi_eh_finish_cmd(scmd, | |
1092 | done_q); | |
1093 | } | |
1094 | } | |
1095 | } else { | |
1096 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: BDR" | |
1097 | " failed sdev:" | |
1098 | "0x%p\n", | |
1099 | current->comm, | |
1100 | sdev)); | |
1101 | } | |
1102 | } | |
1103 | ||
1104 | return list_empty(work_q); | |
1105 | } | |
1106 | ||
30bd7df8 MC |
1107 | /** |
1108 | * scsi_eh_target_reset - send target reset if needed | |
1109 | * @shost: scsi host being recovered. | |
1110 | * @work_q: &list_head for pending commands. | |
1111 | * @done_q: &list_head for processed commands. | |
1112 | * | |
1113 | * Notes: | |
1114 | * Try a target reset. | |
1115 | */ | |
1116 | static int scsi_eh_target_reset(struct Scsi_Host *shost, | |
1117 | struct list_head *work_q, | |
1118 | struct list_head *done_q) | |
1119 | { | |
1120 | struct scsi_cmnd *scmd, *tgtr_scmd, *next; | |
1121 | unsigned int id; | |
1122 | int rtn; | |
1123 | ||
1124 | for (id = 0; id <= shost->max_id; id++) { | |
1125 | tgtr_scmd = NULL; | |
1126 | list_for_each_entry(scmd, work_q, eh_entry) { | |
1127 | if (id == scmd_id(scmd)) { | |
1128 | tgtr_scmd = scmd; | |
1129 | break; | |
1130 | } | |
1131 | } | |
1132 | if (!tgtr_scmd) | |
1133 | continue; | |
1134 | ||
1135 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending target reset " | |
1136 | "to target %d\n", | |
1137 | current->comm, id)); | |
1138 | rtn = scsi_try_target_reset(tgtr_scmd); | |
1139 | if (rtn == SUCCESS) { | |
1140 | list_for_each_entry_safe(scmd, next, work_q, eh_entry) { | |
1141 | if (id == scmd_id(scmd)) | |
1142 | if (!scsi_device_online(scmd->device) || | |
1143 | !scsi_eh_tur(tgtr_scmd)) | |
1144 | scsi_eh_finish_cmd(scmd, | |
1145 | done_q); | |
1146 | } | |
1147 | } else | |
1148 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Target reset" | |
1149 | " failed target: " | |
1150 | "%d\n", | |
1151 | current->comm, id)); | |
1152 | } | |
1153 | ||
1154 | return list_empty(work_q); | |
1155 | } | |
1156 | ||
1da177e4 LT |
1157 | /** |
1158 | * scsi_eh_bus_reset - send a bus reset | |
eb44820c RL |
1159 | * @shost: &scsi host being recovered. |
1160 | * @work_q: &list_head for pending commands. | |
1161 | * @done_q: &list_head for processed commands. | |
dc8875e1 | 1162 | */ |
1da177e4 LT |
1163 | static int scsi_eh_bus_reset(struct Scsi_Host *shost, |
1164 | struct list_head *work_q, | |
1165 | struct list_head *done_q) | |
1166 | { | |
937abeaa | 1167 | struct scsi_cmnd *scmd, *chan_scmd, *next; |
1da177e4 LT |
1168 | unsigned int channel; |
1169 | int rtn; | |
1170 | ||
1171 | /* | |
1172 | * we really want to loop over the various channels, and do this on | |
1173 | * a channel by channel basis. we should also check to see if any | |
1174 | * of the failed commands are on soft_reset devices, and if so, skip | |
1175 | * the reset. | |
1176 | */ | |
1177 | ||
1178 | for (channel = 0; channel <= shost->max_channel; channel++) { | |
1179 | chan_scmd = NULL; | |
1180 | list_for_each_entry(scmd, work_q, eh_entry) { | |
422c0d61 | 1181 | if (channel == scmd_channel(scmd)) { |
1da177e4 LT |
1182 | chan_scmd = scmd; |
1183 | break; | |
1184 | /* | |
1185 | * FIXME add back in some support for | |
1186 | * soft_reset devices. | |
1187 | */ | |
1188 | } | |
1189 | } | |
1190 | ||
1191 | if (!chan_scmd) | |
1192 | continue; | |
1193 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending BRST chan:" | |
1194 | " %d\n", current->comm, | |
1195 | channel)); | |
1196 | rtn = scsi_try_bus_reset(chan_scmd); | |
1197 | if (rtn == SUCCESS) { | |
937abeaa | 1198 | list_for_each_entry_safe(scmd, next, work_q, eh_entry) { |
422c0d61 | 1199 | if (channel == scmd_channel(scmd)) |
1da177e4 LT |
1200 | if (!scsi_device_online(scmd->device) || |
1201 | !scsi_eh_tur(scmd)) | |
1202 | scsi_eh_finish_cmd(scmd, | |
1203 | done_q); | |
1204 | } | |
1205 | } else { | |
1206 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: BRST" | |
1207 | " failed chan: %d\n", | |
1208 | current->comm, | |
1209 | channel)); | |
1210 | } | |
1211 | } | |
1212 | return list_empty(work_q); | |
1213 | } | |
1214 | ||
1215 | /** | |
1216 | * scsi_eh_host_reset - send a host reset | |
1217 | * @work_q: list_head for processed commands. | |
1218 | * @done_q: list_head for processed commands. | |
dc8875e1 | 1219 | */ |
1da177e4 LT |
1220 | static int scsi_eh_host_reset(struct list_head *work_q, |
1221 | struct list_head *done_q) | |
1222 | { | |
937abeaa | 1223 | struct scsi_cmnd *scmd, *next; |
1da177e4 | 1224 | int rtn; |
1da177e4 LT |
1225 | |
1226 | if (!list_empty(work_q)) { | |
1227 | scmd = list_entry(work_q->next, | |
1228 | struct scsi_cmnd, eh_entry); | |
1229 | ||
1230 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending HRST\n" | |
1231 | , current->comm)); | |
1232 | ||
1233 | rtn = scsi_try_host_reset(scmd); | |
1234 | if (rtn == SUCCESS) { | |
937abeaa | 1235 | list_for_each_entry_safe(scmd, next, work_q, eh_entry) { |
1da177e4 LT |
1236 | if (!scsi_device_online(scmd->device) || |
1237 | (!scsi_eh_try_stu(scmd) && !scsi_eh_tur(scmd)) || | |
1238 | !scsi_eh_tur(scmd)) | |
1239 | scsi_eh_finish_cmd(scmd, done_q); | |
1240 | } | |
1241 | } else { | |
1242 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: HRST" | |
1243 | " failed\n", | |
1244 | current->comm)); | |
1245 | } | |
1246 | } | |
1247 | return list_empty(work_q); | |
1248 | } | |
1249 | ||
1250 | /** | |
1251 | * scsi_eh_offline_sdevs - offline scsi devices that fail to recover | |
1252 | * @work_q: list_head for processed commands. | |
1253 | * @done_q: list_head for processed commands. | |
dc8875e1 | 1254 | */ |
1da177e4 LT |
1255 | static void scsi_eh_offline_sdevs(struct list_head *work_q, |
1256 | struct list_head *done_q) | |
1257 | { | |
937abeaa | 1258 | struct scsi_cmnd *scmd, *next; |
1da177e4 | 1259 | |
937abeaa | 1260 | list_for_each_entry_safe(scmd, next, work_q, eh_entry) { |
31765d7d MW |
1261 | sdev_printk(KERN_INFO, scmd->device, "Device offlined - " |
1262 | "not ready after error recovery\n"); | |
1da177e4 | 1263 | scsi_device_set_state(scmd->device, SDEV_OFFLINE); |
3111b0d1 | 1264 | if (scmd->eh_eflags & SCSI_EH_CANCEL_CMD) { |
1da177e4 LT |
1265 | /* |
1266 | * FIXME: Handle lost cmds. | |
1267 | */ | |
1268 | } | |
1269 | scsi_eh_finish_cmd(scmd, done_q); | |
1270 | } | |
1271 | return; | |
1272 | } | |
1273 | ||
1274 | /** | |
1275 | * scsi_decide_disposition - Disposition a cmd on return from LLD. | |
1276 | * @scmd: SCSI cmd to examine. | |
1277 | * | |
1278 | * Notes: | |
1279 | * This is *only* called when we are examining the status after sending | |
1280 | * out the actual data command. any commands that are queued for error | |
1281 | * recovery (e.g. test_unit_ready) do *not* come through here. | |
1282 | * | |
1283 | * When this routine returns failed, it means the error handler thread | |
1284 | * is woken. In cases where the error code indicates an error that | |
1285 | * doesn't require the error handler read (i.e. we don't need to | |
1286 | * abort/reset), this function should return SUCCESS. | |
dc8875e1 | 1287 | */ |
1da177e4 LT |
1288 | int scsi_decide_disposition(struct scsi_cmnd *scmd) |
1289 | { | |
1290 | int rtn; | |
1291 | ||
1292 | /* | |
1293 | * if the device is offline, then we clearly just pass the result back | |
1294 | * up to the top level. | |
1295 | */ | |
1296 | if (!scsi_device_online(scmd->device)) { | |
1297 | SCSI_LOG_ERROR_RECOVERY(5, printk("%s: device offline - report" | |
1298 | " as SUCCESS\n", | |
1299 | __FUNCTION__)); | |
1300 | return SUCCESS; | |
1301 | } | |
1302 | ||
1303 | /* | |
1304 | * first check the host byte, to see if there is anything in there | |
1305 | * that would indicate what we need to do. | |
1306 | */ | |
1307 | switch (host_byte(scmd->result)) { | |
1308 | case DID_PASSTHROUGH: | |
1309 | /* | |
1310 | * no matter what, pass this through to the upper layer. | |
1311 | * nuke this special code so that it looks like we are saying | |
1312 | * did_ok. | |
1313 | */ | |
1314 | scmd->result &= 0xff00ffff; | |
1315 | return SUCCESS; | |
1316 | case DID_OK: | |
1317 | /* | |
1318 | * looks good. drop through, and check the next byte. | |
1319 | */ | |
1320 | break; | |
1321 | case DID_NO_CONNECT: | |
1322 | case DID_BAD_TARGET: | |
1323 | case DID_ABORT: | |
1324 | /* | |
1325 | * note - this means that we just report the status back | |
1326 | * to the top level driver, not that we actually think | |
1327 | * that it indicates SUCCESS. | |
1328 | */ | |
1329 | return SUCCESS; | |
1330 | /* | |
1331 | * when the low level driver returns did_soft_error, | |
1332 | * it is responsible for keeping an internal retry counter | |
1333 | * in order to avoid endless loops (db) | |
1334 | * | |
1335 | * actually this is a bug in this function here. we should | |
1336 | * be mindful of the maximum number of retries specified | |
1337 | * and not get stuck in a loop. | |
1338 | */ | |
1339 | case DID_SOFT_ERROR: | |
1340 | goto maybe_retry; | |
1341 | case DID_IMM_RETRY: | |
1342 | return NEEDS_RETRY; | |
1343 | ||
bf341919 JB |
1344 | case DID_REQUEUE: |
1345 | return ADD_TO_MLQUEUE; | |
1346 | ||
1da177e4 LT |
1347 | case DID_ERROR: |
1348 | if (msg_byte(scmd->result) == COMMAND_COMPLETE && | |
1349 | status_byte(scmd->result) == RESERVATION_CONFLICT) | |
1350 | /* | |
1351 | * execute reservation conflict processing code | |
1352 | * lower down | |
1353 | */ | |
1354 | break; | |
1355 | /* fallthrough */ | |
1356 | ||
1357 | case DID_BUS_BUSY: | |
1358 | case DID_PARITY: | |
1359 | goto maybe_retry; | |
1360 | case DID_TIME_OUT: | |
1361 | /* | |
1362 | * when we scan the bus, we get timeout messages for | |
1363 | * these commands if there is no device available. | |
1364 | * other hosts report did_no_connect for the same thing. | |
1365 | */ | |
1366 | if ((scmd->cmnd[0] == TEST_UNIT_READY || | |
1367 | scmd->cmnd[0] == INQUIRY)) { | |
1368 | return SUCCESS; | |
1369 | } else { | |
1370 | return FAILED; | |
1371 | } | |
1372 | case DID_RESET: | |
1373 | return SUCCESS; | |
1374 | default: | |
1375 | return FAILED; | |
1376 | } | |
1377 | ||
1378 | /* | |
1379 | * next, check the message byte. | |
1380 | */ | |
1381 | if (msg_byte(scmd->result) != COMMAND_COMPLETE) | |
1382 | return FAILED; | |
1383 | ||
1384 | /* | |
1385 | * check the status byte to see if this indicates anything special. | |
1386 | */ | |
1387 | switch (status_byte(scmd->result)) { | |
1388 | case QUEUE_FULL: | |
1389 | /* | |
1390 | * the case of trying to send too many commands to a | |
1391 | * tagged queueing device. | |
1392 | */ | |
1393 | case BUSY: | |
1394 | /* | |
1395 | * device can't talk to us at the moment. Should only | |
1396 | * occur (SAM-3) when the task queue is empty, so will cause | |
1397 | * the empty queue handling to trigger a stall in the | |
1398 | * device. | |
1399 | */ | |
1400 | return ADD_TO_MLQUEUE; | |
1401 | case GOOD: | |
1402 | case COMMAND_TERMINATED: | |
1403 | case TASK_ABORTED: | |
1404 | return SUCCESS; | |
1405 | case CHECK_CONDITION: | |
1406 | rtn = scsi_check_sense(scmd); | |
1407 | if (rtn == NEEDS_RETRY) | |
1408 | goto maybe_retry; | |
1409 | /* if rtn == FAILED, we have no sense information; | |
1410 | * returning FAILED will wake the error handler thread | |
1411 | * to collect the sense and redo the decide | |
1412 | * disposition */ | |
1413 | return rtn; | |
1414 | case CONDITION_GOOD: | |
1415 | case INTERMEDIATE_GOOD: | |
1416 | case INTERMEDIATE_C_GOOD: | |
1417 | case ACA_ACTIVE: | |
1418 | /* | |
1419 | * who knows? FIXME(eric) | |
1420 | */ | |
1421 | return SUCCESS; | |
1422 | ||
1423 | case RESERVATION_CONFLICT: | |
9ccfc756 JB |
1424 | sdev_printk(KERN_INFO, scmd->device, |
1425 | "reservation conflict\n"); | |
1da177e4 LT |
1426 | return SUCCESS; /* causes immediate i/o error */ |
1427 | default: | |
1428 | return FAILED; | |
1429 | } | |
1430 | return FAILED; | |
1431 | ||
1432 | maybe_retry: | |
1433 | ||
1434 | /* we requeue for retry because the error was retryable, and | |
1435 | * the request was not marked fast fail. Note that above, | |
1436 | * even if the request is marked fast fail, we still requeue | |
1437 | * for queue congestion conditions (QUEUE_FULL or BUSY) */ | |
8884efab | 1438 | if ((++scmd->retries) <= scmd->allowed |
1da177e4 LT |
1439 | && !blk_noretry_request(scmd->request)) { |
1440 | return NEEDS_RETRY; | |
1441 | } else { | |
1442 | /* | |
1443 | * no more retries - report this one back to upper level. | |
1444 | */ | |
1445 | return SUCCESS; | |
1446 | } | |
1447 | } | |
1448 | ||
1da177e4 LT |
1449 | /** |
1450 | * scsi_eh_lock_door - Prevent medium removal for the specified device | |
1451 | * @sdev: SCSI device to prevent medium removal | |
1452 | * | |
1453 | * Locking: | |
1454 | * We must be called from process context; scsi_allocate_request() | |
1455 | * may sleep. | |
1456 | * | |
1457 | * Notes: | |
1458 | * We queue up an asynchronous "ALLOW MEDIUM REMOVAL" request on the | |
1459 | * head of the devices request queue, and continue. | |
1460 | * | |
1461 | * Bugs: | |
1462 | * scsi_allocate_request() may sleep waiting for existing requests to | |
1463 | * be processed. However, since we haven't kicked off any request | |
1464 | * processing for this host, this may deadlock. | |
1465 | * | |
1466 | * If scsi_allocate_request() fails for what ever reason, we | |
1467 | * completely forget to lock the door. | |
dc8875e1 | 1468 | */ |
1da177e4 LT |
1469 | static void scsi_eh_lock_door(struct scsi_device *sdev) |
1470 | { | |
6e68af66 | 1471 | unsigned char cmnd[MAX_COMMAND_SIZE]; |
1da177e4 | 1472 | |
6e68af66 MC |
1473 | cmnd[0] = ALLOW_MEDIUM_REMOVAL; |
1474 | cmnd[1] = 0; | |
1475 | cmnd[2] = 0; | |
1476 | cmnd[3] = 0; | |
1477 | cmnd[4] = SCSI_REMOVAL_PREVENT; | |
1478 | cmnd[5] = 0; | |
1da177e4 | 1479 | |
bb1d1073 | 1480 | scsi_execute_async(sdev, cmnd, 6, DMA_NONE, NULL, 0, 0, 10 * HZ, |
6e68af66 | 1481 | 5, NULL, NULL, GFP_KERNEL); |
1da177e4 LT |
1482 | } |
1483 | ||
1484 | ||
1485 | /** | |
1486 | * scsi_restart_operations - restart io operations to the specified host. | |
1487 | * @shost: Host we are restarting. | |
1488 | * | |
1489 | * Notes: | |
1490 | * When we entered the error handler, we blocked all further i/o to | |
1491 | * this device. we need to 'reverse' this process. | |
dc8875e1 | 1492 | */ |
1da177e4 LT |
1493 | static void scsi_restart_operations(struct Scsi_Host *shost) |
1494 | { | |
1495 | struct scsi_device *sdev; | |
939647ee | 1496 | unsigned long flags; |
1da177e4 LT |
1497 | |
1498 | /* | |
1499 | * If the door was locked, we need to insert a door lock request | |
1500 | * onto the head of the SCSI request queue for the device. There | |
1501 | * is no point trying to lock the door of an off-line device. | |
1502 | */ | |
1503 | shost_for_each_device(sdev, shost) { | |
1504 | if (scsi_device_online(sdev) && sdev->locked) | |
1505 | scsi_eh_lock_door(sdev); | |
1506 | } | |
1507 | ||
1508 | /* | |
1509 | * next free up anything directly waiting upon the host. this | |
1510 | * will be requests for character device operations, and also for | |
1511 | * ioctls to queued block devices. | |
1512 | */ | |
1513 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: waking up host to restart\n", | |
1514 | __FUNCTION__)); | |
1515 | ||
939647ee JB |
1516 | spin_lock_irqsave(shost->host_lock, flags); |
1517 | if (scsi_host_set_state(shost, SHOST_RUNNING)) | |
1518 | if (scsi_host_set_state(shost, SHOST_CANCEL)) | |
1519 | BUG_ON(scsi_host_set_state(shost, SHOST_DEL)); | |
1520 | spin_unlock_irqrestore(shost->host_lock, flags); | |
1da177e4 LT |
1521 | |
1522 | wake_up(&shost->host_wait); | |
1523 | ||
1524 | /* | |
1525 | * finally we need to re-initiate requests that may be pending. we will | |
1526 | * have had everything blocked while error handling is taking place, and | |
1527 | * now that error recovery is done, we will need to ensure that these | |
1528 | * requests are started. | |
1529 | */ | |
1530 | scsi_run_host_queues(shost); | |
1531 | } | |
1532 | ||
1533 | /** | |
1534 | * scsi_eh_ready_devs - check device ready state and recover if not. | |
1535 | * @shost: host to be recovered. | |
eb44820c RL |
1536 | * @work_q: &list_head for pending commands. |
1537 | * @done_q: &list_head for processed commands. | |
dc8875e1 | 1538 | */ |
dca84e46 DW |
1539 | void scsi_eh_ready_devs(struct Scsi_Host *shost, |
1540 | struct list_head *work_q, | |
1541 | struct list_head *done_q) | |
1da177e4 LT |
1542 | { |
1543 | if (!scsi_eh_stu(shost, work_q, done_q)) | |
1544 | if (!scsi_eh_bus_device_reset(shost, work_q, done_q)) | |
30bd7df8 MC |
1545 | if (!scsi_eh_target_reset(shost, work_q, done_q)) |
1546 | if (!scsi_eh_bus_reset(shost, work_q, done_q)) | |
1547 | if (!scsi_eh_host_reset(work_q, done_q)) | |
1548 | scsi_eh_offline_sdevs(work_q, | |
1549 | done_q); | |
1da177e4 | 1550 | } |
dca84e46 | 1551 | EXPORT_SYMBOL_GPL(scsi_eh_ready_devs); |
1da177e4 LT |
1552 | |
1553 | /** | |
1554 | * scsi_eh_flush_done_q - finish processed commands or retry them. | |
1555 | * @done_q: list_head of processed commands. | |
dc8875e1 | 1556 | */ |
041c5fc3 | 1557 | void scsi_eh_flush_done_q(struct list_head *done_q) |
1da177e4 | 1558 | { |
937abeaa | 1559 | struct scsi_cmnd *scmd, *next; |
1da177e4 | 1560 | |
937abeaa CH |
1561 | list_for_each_entry_safe(scmd, next, done_q, eh_entry) { |
1562 | list_del_init(&scmd->eh_entry); | |
1da177e4 LT |
1563 | if (scsi_device_online(scmd->device) && |
1564 | !blk_noretry_request(scmd->request) && | |
8884efab | 1565 | (++scmd->retries <= scmd->allowed)) { |
1da177e4 LT |
1566 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: flush" |
1567 | " retry cmd: %p\n", | |
1568 | current->comm, | |
1569 | scmd)); | |
1570 | scsi_queue_insert(scmd, SCSI_MLQUEUE_EH_RETRY); | |
1571 | } else { | |
793698ce PM |
1572 | /* |
1573 | * If just we got sense for the device (called | |
1574 | * scsi_eh_get_sense), scmd->result is already | |
1575 | * set, do not set DRIVER_TIMEOUT. | |
1576 | */ | |
1da177e4 LT |
1577 | if (!scmd->result) |
1578 | scmd->result |= (DRIVER_TIMEOUT << 24); | |
1579 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: flush finish" | |
1580 | " cmd: %p\n", | |
1581 | current->comm, scmd)); | |
1582 | scsi_finish_command(scmd); | |
1583 | } | |
1584 | } | |
1585 | } | |
041c5fc3 | 1586 | EXPORT_SYMBOL(scsi_eh_flush_done_q); |
1da177e4 LT |
1587 | |
1588 | /** | |
1589 | * scsi_unjam_host - Attempt to fix a host which has a cmd that failed. | |
1590 | * @shost: Host to unjam. | |
1591 | * | |
1592 | * Notes: | |
1593 | * When we come in here, we *know* that all commands on the bus have | |
1594 | * either completed, failed or timed out. we also know that no further | |
1595 | * commands are being sent to the host, so things are relatively quiet | |
1596 | * and we have freedom to fiddle with things as we wish. | |
1597 | * | |
1598 | * This is only the *default* implementation. it is possible for | |
1599 | * individual drivers to supply their own version of this function, and | |
1600 | * if the maintainer wishes to do this, it is strongly suggested that | |
1601 | * this function be taken as a template and modified. this function | |
1602 | * was designed to correctly handle problems for about 95% of the | |
1603 | * different cases out there, and it should always provide at least a | |
1604 | * reasonable amount of error recovery. | |
1605 | * | |
1606 | * Any command marked 'failed' or 'timeout' must eventually have | |
1607 | * scsi_finish_cmd() called for it. we do all of the retry stuff | |
1608 | * here, so when we restart the host after we return it should have an | |
1609 | * empty queue. | |
dc8875e1 | 1610 | */ |
1da177e4 LT |
1611 | static void scsi_unjam_host(struct Scsi_Host *shost) |
1612 | { | |
1613 | unsigned long flags; | |
1614 | LIST_HEAD(eh_work_q); | |
1615 | LIST_HEAD(eh_done_q); | |
1616 | ||
1617 | spin_lock_irqsave(shost->host_lock, flags); | |
1618 | list_splice_init(&shost->eh_cmd_q, &eh_work_q); | |
1619 | spin_unlock_irqrestore(shost->host_lock, flags); | |
1620 | ||
1621 | SCSI_LOG_ERROR_RECOVERY(1, scsi_eh_prt_fail_stats(shost, &eh_work_q)); | |
1622 | ||
1623 | if (!scsi_eh_get_sense(&eh_work_q, &eh_done_q)) | |
1624 | if (!scsi_eh_abort_cmds(&eh_work_q, &eh_done_q)) | |
1625 | scsi_eh_ready_devs(shost, &eh_work_q, &eh_done_q); | |
1626 | ||
1627 | scsi_eh_flush_done_q(&eh_done_q); | |
1628 | } | |
1629 | ||
1630 | /** | |
ad42eb1b | 1631 | * scsi_error_handler - SCSI error handler thread |
1da177e4 LT |
1632 | * @data: Host for which we are running. |
1633 | * | |
1634 | * Notes: | |
ad42eb1b CH |
1635 | * This is the main error handling loop. This is run as a kernel thread |
1636 | * for every SCSI host and handles all error handling activity. | |
dc8875e1 | 1637 | */ |
1da177e4 LT |
1638 | int scsi_error_handler(void *data) |
1639 | { | |
ad42eb1b | 1640 | struct Scsi_Host *shost = data; |
1da177e4 | 1641 | |
1da177e4 | 1642 | /* |
ad42eb1b CH |
1643 | * We use TASK_INTERRUPTIBLE so that the thread is not |
1644 | * counted against the load average as a running process. | |
1645 | * We never actually get interrupted because kthread_run | |
1646 | * disables singal delivery for the created thread. | |
1da177e4 | 1647 | */ |
3ed7a470 JB |
1648 | set_current_state(TASK_INTERRUPTIBLE); |
1649 | while (!kthread_should_stop()) { | |
ee7863bc | 1650 | if ((shost->host_failed == 0 && shost->host_eh_scheduled == 0) || |
3ed7a470 | 1651 | shost->host_failed != shost->host_busy) { |
ad42eb1b CH |
1652 | SCSI_LOG_ERROR_RECOVERY(1, |
1653 | printk("Error handler scsi_eh_%d sleeping\n", | |
1654 | shost->host_no)); | |
3ed7a470 JB |
1655 | schedule(); |
1656 | set_current_state(TASK_INTERRUPTIBLE); | |
1657 | continue; | |
1658 | } | |
1da177e4 | 1659 | |
3ed7a470 | 1660 | __set_current_state(TASK_RUNNING); |
ad42eb1b CH |
1661 | SCSI_LOG_ERROR_RECOVERY(1, |
1662 | printk("Error handler scsi_eh_%d waking up\n", | |
1663 | shost->host_no)); | |
1da177e4 | 1664 | |
1da177e4 LT |
1665 | /* |
1666 | * We have a host that is failing for some reason. Figure out | |
1667 | * what we need to do to get it up and online again (if we can). | |
1668 | * If we fail, we end up taking the thing offline. | |
1669 | */ | |
9227c33d CH |
1670 | if (shost->transportt->eh_strategy_handler) |
1671 | shost->transportt->eh_strategy_handler(shost); | |
1da177e4 LT |
1672 | else |
1673 | scsi_unjam_host(shost); | |
1674 | ||
1da177e4 LT |
1675 | /* |
1676 | * Note - if the above fails completely, the action is to take | |
1677 | * individual devices offline and flush the queue of any | |
1678 | * outstanding requests that may have been pending. When we | |
1679 | * restart, we restart any I/O to any other devices on the bus | |
1680 | * which are still online. | |
1681 | */ | |
1682 | scsi_restart_operations(shost); | |
3ed7a470 | 1683 | set_current_state(TASK_INTERRUPTIBLE); |
1da177e4 | 1684 | } |
461a0ffb SR |
1685 | __set_current_state(TASK_RUNNING); |
1686 | ||
ad42eb1b CH |
1687 | SCSI_LOG_ERROR_RECOVERY(1, |
1688 | printk("Error handler scsi_eh_%d exiting\n", shost->host_no)); | |
3ed7a470 | 1689 | shost->ehandler = NULL; |
1da177e4 LT |
1690 | return 0; |
1691 | } | |
1692 | ||
1693 | /* | |
1694 | * Function: scsi_report_bus_reset() | |
1695 | * | |
1696 | * Purpose: Utility function used by low-level drivers to report that | |
1697 | * they have observed a bus reset on the bus being handled. | |
1698 | * | |
1699 | * Arguments: shost - Host in question | |
1700 | * channel - channel on which reset was observed. | |
1701 | * | |
1702 | * Returns: Nothing | |
1703 | * | |
1704 | * Lock status: Host lock must be held. | |
1705 | * | |
1706 | * Notes: This only needs to be called if the reset is one which | |
1707 | * originates from an unknown location. Resets originated | |
1708 | * by the mid-level itself don't need to call this, but there | |
1709 | * should be no harm. | |
1710 | * | |
1711 | * The main purpose of this is to make sure that a CHECK_CONDITION | |
1712 | * is properly treated. | |
1713 | */ | |
1714 | void scsi_report_bus_reset(struct Scsi_Host *shost, int channel) | |
1715 | { | |
1716 | struct scsi_device *sdev; | |
1717 | ||
1718 | __shost_for_each_device(sdev, shost) { | |
30bd7df8 MC |
1719 | if (channel == sdev_channel(sdev)) |
1720 | __scsi_report_device_reset(sdev, NULL); | |
1da177e4 LT |
1721 | } |
1722 | } | |
1723 | EXPORT_SYMBOL(scsi_report_bus_reset); | |
1724 | ||
1725 | /* | |
1726 | * Function: scsi_report_device_reset() | |
1727 | * | |
1728 | * Purpose: Utility function used by low-level drivers to report that | |
1729 | * they have observed a device reset on the device being handled. | |
1730 | * | |
1731 | * Arguments: shost - Host in question | |
1732 | * channel - channel on which reset was observed | |
1733 | * target - target on which reset was observed | |
1734 | * | |
1735 | * Returns: Nothing | |
1736 | * | |
1737 | * Lock status: Host lock must be held | |
1738 | * | |
1739 | * Notes: This only needs to be called if the reset is one which | |
1740 | * originates from an unknown location. Resets originated | |
1741 | * by the mid-level itself don't need to call this, but there | |
1742 | * should be no harm. | |
1743 | * | |
1744 | * The main purpose of this is to make sure that a CHECK_CONDITION | |
1745 | * is properly treated. | |
1746 | */ | |
1747 | void scsi_report_device_reset(struct Scsi_Host *shost, int channel, int target) | |
1748 | { | |
1749 | struct scsi_device *sdev; | |
1750 | ||
1751 | __shost_for_each_device(sdev, shost) { | |
422c0d61 | 1752 | if (channel == sdev_channel(sdev) && |
30bd7df8 MC |
1753 | target == sdev_id(sdev)) |
1754 | __scsi_report_device_reset(sdev, NULL); | |
1da177e4 LT |
1755 | } |
1756 | } | |
1757 | EXPORT_SYMBOL(scsi_report_device_reset); | |
1758 | ||
1759 | static void | |
1760 | scsi_reset_provider_done_command(struct scsi_cmnd *scmd) | |
1761 | { | |
1762 | } | |
1763 | ||
1764 | /* | |
1765 | * Function: scsi_reset_provider | |
1766 | * | |
1767 | * Purpose: Send requested reset to a bus or device at any phase. | |
1768 | * | |
1769 | * Arguments: device - device to send reset to | |
1770 | * flag - reset type (see scsi.h) | |
1771 | * | |
1772 | * Returns: SUCCESS/FAILURE. | |
1773 | * | |
1774 | * Notes: This is used by the SCSI Generic driver to provide | |
1775 | * Bus/Device reset capability. | |
1776 | */ | |
1777 | int | |
1778 | scsi_reset_provider(struct scsi_device *dev, int flag) | |
1779 | { | |
1780 | struct scsi_cmnd *scmd = scsi_get_command(dev, GFP_KERNEL); | |
d7a1bb0a | 1781 | struct Scsi_Host *shost = dev->host; |
1da177e4 | 1782 | struct request req; |
d7a1bb0a | 1783 | unsigned long flags; |
1da177e4 LT |
1784 | int rtn; |
1785 | ||
4f54eec8 | 1786 | blk_rq_init(NULL, &req); |
1da177e4 LT |
1787 | scmd->request = &req; |
1788 | memset(&scmd->eh_timeout, 0, sizeof(scmd->eh_timeout)); | |
b4edcbca | 1789 | |
64a87b24 BH |
1790 | scmd->cmnd = req.cmd; |
1791 | ||
1da177e4 | 1792 | scmd->scsi_done = scsi_reset_provider_done_command; |
30b0c37b | 1793 | memset(&scmd->sdb, 0, sizeof(scmd->sdb)); |
1da177e4 LT |
1794 | |
1795 | scmd->cmd_len = 0; | |
1796 | ||
1797 | scmd->sc_data_direction = DMA_BIDIRECTIONAL; | |
1da177e4 LT |
1798 | |
1799 | init_timer(&scmd->eh_timeout); | |
1800 | ||
d7a1bb0a JS |
1801 | spin_lock_irqsave(shost->host_lock, flags); |
1802 | shost->tmf_in_progress = 1; | |
1803 | spin_unlock_irqrestore(shost->host_lock, flags); | |
1804 | ||
1da177e4 LT |
1805 | switch (flag) { |
1806 | case SCSI_TRY_RESET_DEVICE: | |
1807 | rtn = scsi_try_bus_device_reset(scmd); | |
1808 | if (rtn == SUCCESS) | |
1809 | break; | |
1810 | /* FALLTHROUGH */ | |
30bd7df8 MC |
1811 | case SCSI_TRY_RESET_TARGET: |
1812 | rtn = scsi_try_target_reset(scmd); | |
1813 | if (rtn == SUCCESS) | |
1814 | break; | |
1815 | /* FALLTHROUGH */ | |
1da177e4 LT |
1816 | case SCSI_TRY_RESET_BUS: |
1817 | rtn = scsi_try_bus_reset(scmd); | |
1818 | if (rtn == SUCCESS) | |
1819 | break; | |
1820 | /* FALLTHROUGH */ | |
1821 | case SCSI_TRY_RESET_HOST: | |
1822 | rtn = scsi_try_host_reset(scmd); | |
1823 | break; | |
1824 | default: | |
1825 | rtn = FAILED; | |
1826 | } | |
1827 | ||
d7a1bb0a JS |
1828 | spin_lock_irqsave(shost->host_lock, flags); |
1829 | shost->tmf_in_progress = 0; | |
1830 | spin_unlock_irqrestore(shost->host_lock, flags); | |
1831 | ||
1832 | /* | |
1833 | * be sure to wake up anyone who was sleeping or had their queue | |
1834 | * suspended while we performed the TMF. | |
1835 | */ | |
1836 | SCSI_LOG_ERROR_RECOVERY(3, | |
1837 | printk("%s: waking up host to restart after TMF\n", | |
1838 | __FUNCTION__)); | |
1839 | ||
1840 | wake_up(&shost->host_wait); | |
1841 | ||
1842 | scsi_run_host_queues(shost); | |
1843 | ||
1da177e4 LT |
1844 | scsi_next_command(scmd); |
1845 | return rtn; | |
1846 | } | |
1847 | EXPORT_SYMBOL(scsi_reset_provider); | |
1848 | ||
1849 | /** | |
1850 | * scsi_normalize_sense - normalize main elements from either fixed or | |
1851 | * descriptor sense data format into a common format. | |
1852 | * | |
1853 | * @sense_buffer: byte array containing sense data returned by device | |
1854 | * @sb_len: number of valid bytes in sense_buffer | |
1855 | * @sshdr: pointer to instance of structure that common | |
1856 | * elements are written to. | |
1857 | * | |
1858 | * Notes: | |
1859 | * The "main elements" from sense data are: response_code, sense_key, | |
1860 | * asc, ascq and additional_length (only for descriptor format). | |
1861 | * | |
1862 | * Typically this function can be called after a device has | |
1863 | * responded to a SCSI command with the CHECK_CONDITION status. | |
1864 | * | |
1865 | * Return value: | |
1866 | * 1 if valid sense data information found, else 0; | |
dc8875e1 | 1867 | */ |
1da177e4 LT |
1868 | int scsi_normalize_sense(const u8 *sense_buffer, int sb_len, |
1869 | struct scsi_sense_hdr *sshdr) | |
1870 | { | |
33aa687d | 1871 | if (!sense_buffer || !sb_len) |
1da177e4 LT |
1872 | return 0; |
1873 | ||
1874 | memset(sshdr, 0, sizeof(struct scsi_sense_hdr)); | |
1875 | ||
1876 | sshdr->response_code = (sense_buffer[0] & 0x7f); | |
33aa687d JB |
1877 | |
1878 | if (!scsi_sense_valid(sshdr)) | |
1879 | return 0; | |
1880 | ||
1da177e4 LT |
1881 | if (sshdr->response_code >= 0x72) { |
1882 | /* | |
1883 | * descriptor format | |
1884 | */ | |
1885 | if (sb_len > 1) | |
1886 | sshdr->sense_key = (sense_buffer[1] & 0xf); | |
1887 | if (sb_len > 2) | |
1888 | sshdr->asc = sense_buffer[2]; | |
1889 | if (sb_len > 3) | |
1890 | sshdr->ascq = sense_buffer[3]; | |
1891 | if (sb_len > 7) | |
1892 | sshdr->additional_length = sense_buffer[7]; | |
1893 | } else { | |
1894 | /* | |
1895 | * fixed format | |
1896 | */ | |
1897 | if (sb_len > 2) | |
1898 | sshdr->sense_key = (sense_buffer[2] & 0xf); | |
1899 | if (sb_len > 7) { | |
1900 | sb_len = (sb_len < (sense_buffer[7] + 8)) ? | |
1901 | sb_len : (sense_buffer[7] + 8); | |
1902 | if (sb_len > 12) | |
1903 | sshdr->asc = sense_buffer[12]; | |
1904 | if (sb_len > 13) | |
1905 | sshdr->ascq = sense_buffer[13]; | |
1906 | } | |
1907 | } | |
1908 | ||
1909 | return 1; | |
1910 | } | |
1911 | EXPORT_SYMBOL(scsi_normalize_sense); | |
1912 | ||
1da177e4 LT |
1913 | int scsi_command_normalize_sense(struct scsi_cmnd *cmd, |
1914 | struct scsi_sense_hdr *sshdr) | |
1915 | { | |
1916 | return scsi_normalize_sense(cmd->sense_buffer, | |
b80ca4f7 | 1917 | SCSI_SENSE_BUFFERSIZE, sshdr); |
1da177e4 LT |
1918 | } |
1919 | EXPORT_SYMBOL(scsi_command_normalize_sense); | |
1920 | ||
1921 | /** | |
eb44820c | 1922 | * scsi_sense_desc_find - search for a given descriptor type in descriptor sense data format. |
1da177e4 LT |
1923 | * @sense_buffer: byte array of descriptor format sense data |
1924 | * @sb_len: number of valid bytes in sense_buffer | |
1925 | * @desc_type: value of descriptor type to find | |
1926 | * (e.g. 0 -> information) | |
1927 | * | |
1928 | * Notes: | |
1929 | * only valid when sense data is in descriptor format | |
1930 | * | |
1931 | * Return value: | |
1932 | * pointer to start of (first) descriptor if found else NULL | |
dc8875e1 | 1933 | */ |
1da177e4 LT |
1934 | const u8 * scsi_sense_desc_find(const u8 * sense_buffer, int sb_len, |
1935 | int desc_type) | |
1936 | { | |
1937 | int add_sen_len, add_len, desc_len, k; | |
1938 | const u8 * descp; | |
1939 | ||
1940 | if ((sb_len < 8) || (0 == (add_sen_len = sense_buffer[7]))) | |
1941 | return NULL; | |
1942 | if ((sense_buffer[0] < 0x72) || (sense_buffer[0] > 0x73)) | |
1943 | return NULL; | |
1944 | add_sen_len = (add_sen_len < (sb_len - 8)) ? | |
1945 | add_sen_len : (sb_len - 8); | |
1946 | descp = &sense_buffer[8]; | |
1947 | for (desc_len = 0, k = 0; k < add_sen_len; k += desc_len) { | |
1948 | descp += desc_len; | |
1949 | add_len = (k < (add_sen_len - 1)) ? descp[1]: -1; | |
1950 | desc_len = add_len + 2; | |
1951 | if (descp[0] == desc_type) | |
1952 | return descp; | |
1953 | if (add_len < 0) // short descriptor ?? | |
1954 | break; | |
1955 | } | |
1956 | return NULL; | |
1957 | } | |
1958 | EXPORT_SYMBOL(scsi_sense_desc_find); | |
1959 | ||
1960 | /** | |
eb44820c | 1961 | * scsi_get_sense_info_fld - get information field from sense data (either fixed or descriptor format) |
1da177e4 LT |
1962 | * @sense_buffer: byte array of sense data |
1963 | * @sb_len: number of valid bytes in sense_buffer | |
1964 | * @info_out: pointer to 64 integer where 8 or 4 byte information | |
1965 | * field will be placed if found. | |
1966 | * | |
1967 | * Return value: | |
1968 | * 1 if information field found, 0 if not found. | |
dc8875e1 | 1969 | */ |
1da177e4 LT |
1970 | int scsi_get_sense_info_fld(const u8 * sense_buffer, int sb_len, |
1971 | u64 * info_out) | |
1972 | { | |
1973 | int j; | |
1974 | const u8 * ucp; | |
1975 | u64 ull; | |
1976 | ||
1977 | if (sb_len < 7) | |
1978 | return 0; | |
1979 | switch (sense_buffer[0] & 0x7f) { | |
1980 | case 0x70: | |
1981 | case 0x71: | |
1982 | if (sense_buffer[0] & 0x80) { | |
1983 | *info_out = (sense_buffer[3] << 24) + | |
1984 | (sense_buffer[4] << 16) + | |
1985 | (sense_buffer[5] << 8) + sense_buffer[6]; | |
1986 | return 1; | |
1987 | } else | |
1988 | return 0; | |
1989 | case 0x72: | |
1990 | case 0x73: | |
1991 | ucp = scsi_sense_desc_find(sense_buffer, sb_len, | |
1992 | 0 /* info desc */); | |
1993 | if (ucp && (0xa == ucp[1])) { | |
1994 | ull = 0; | |
1995 | for (j = 0; j < 8; ++j) { | |
1996 | if (j > 0) | |
1997 | ull <<= 8; | |
1998 | ull |= ucp[4 + j]; | |
1999 | } | |
2000 | *info_out = ull; | |
2001 | return 1; | |
2002 | } else | |
2003 | return 0; | |
2004 | default: | |
2005 | return 0; | |
2006 | } | |
2007 | } | |
2008 | EXPORT_SYMBOL(scsi_get_sense_info_fld); | |
3bc6a261 FT |
2009 | |
2010 | /** | |
2011 | * scsi_build_sense_buffer - build sense data in a buffer | |
2012 | * @desc: Sense format (non zero == descriptor format, | |
2013 | * 0 == fixed format) | |
2014 | * @buf: Where to build sense data | |
2015 | * @key: Sense key | |
2016 | * @asc: Additional sense code | |
2017 | * @ascq: Additional sense code qualifier | |
2018 | * | |
2019 | **/ | |
2020 | void scsi_build_sense_buffer(int desc, u8 *buf, u8 key, u8 asc, u8 ascq) | |
2021 | { | |
2022 | if (desc) { | |
2023 | buf[0] = 0x72; /* descriptor, current */ | |
2024 | buf[1] = key; | |
2025 | buf[2] = asc; | |
2026 | buf[3] = ascq; | |
2027 | buf[7] = 0; | |
2028 | } else { | |
2029 | buf[0] = 0x70; /* fixed, current */ | |
2030 | buf[2] = key; | |
2031 | buf[7] = 0xa; | |
2032 | buf[12] = asc; | |
2033 | buf[13] = ascq; | |
2034 | } | |
2035 | } | |
2036 | EXPORT_SYMBOL(scsi_build_sense_buffer); |