Commit | Line | Data |
---|---|---|
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> | |
355dfa1b | 27 | #include <linux/scatterlist.h> |
1da177e4 LT |
28 | |
29 | #include <scsi/scsi.h> | |
beb40487 | 30 | #include <scsi/scsi_cmnd.h> |
1da177e4 LT |
31 | #include <scsi/scsi_dbg.h> |
32 | #include <scsi/scsi_device.h> | |
33 | #include <scsi/scsi_eh.h> | |
c829c394 | 34 | #include <scsi/scsi_transport.h> |
1da177e4 LT |
35 | #include <scsi/scsi_host.h> |
36 | #include <scsi/scsi_ioctl.h> | |
1da177e4 LT |
37 | |
38 | #include "scsi_priv.h" | |
39 | #include "scsi_logging.h" | |
79ee8304 | 40 | #include "scsi_transport_api.h" |
1da177e4 LT |
41 | |
42 | #define SENSE_TIMEOUT (10*HZ) | |
1da177e4 LT |
43 | |
44 | /* | |
45 | * These should *probably* be handled by the host itself. | |
46 | * Since it is allowed to sleep, it probably should. | |
47 | */ | |
48 | #define BUS_RESET_SETTLE_TIME (10) | |
49 | #define HOST_RESET_SETTLE_TIME (10) | |
50 | ||
51 | /* called with shost->host_lock held */ | |
52 | void scsi_eh_wakeup(struct Scsi_Host *shost) | |
53 | { | |
54 | if (shost->host_busy == shost->host_failed) { | |
3ed7a470 | 55 | wake_up_process(shost->ehandler); |
1da177e4 LT |
56 | SCSI_LOG_ERROR_RECOVERY(5, |
57 | printk("Waking error handler thread\n")); | |
58 | } | |
59 | } | |
f8bbfc24 TH |
60 | |
61 | /** | |
62 | * scsi_schedule_eh - schedule EH for SCSI host | |
63 | * @shost: SCSI host to invoke error handling on. | |
64 | * | |
65 | * Schedule SCSI EH without scmd. | |
66 | **/ | |
67 | void scsi_schedule_eh(struct Scsi_Host *shost) | |
68 | { | |
69 | unsigned long flags; | |
70 | ||
71 | spin_lock_irqsave(shost->host_lock, flags); | |
72 | ||
73 | if (scsi_host_set_state(shost, SHOST_RECOVERY) == 0 || | |
74 | scsi_host_set_state(shost, SHOST_CANCEL_RECOVERY) == 0) { | |
75 | shost->host_eh_scheduled++; | |
76 | scsi_eh_wakeup(shost); | |
77 | } | |
78 | ||
79 | spin_unlock_irqrestore(shost->host_lock, flags); | |
80 | } | |
81 | EXPORT_SYMBOL_GPL(scsi_schedule_eh); | |
1da177e4 LT |
82 | |
83 | /** | |
84 | * scsi_eh_scmd_add - add scsi cmd to error handling. | |
85 | * @scmd: scmd to run eh on. | |
86 | * @eh_flag: optional SCSI_EH flag. | |
87 | * | |
88 | * Return value: | |
89 | * 0 on failure. | |
90 | **/ | |
91 | int scsi_eh_scmd_add(struct scsi_cmnd *scmd, int eh_flag) | |
92 | { | |
93 | struct Scsi_Host *shost = scmd->device->host; | |
94 | unsigned long flags; | |
939647ee | 95 | int ret = 0; |
1da177e4 | 96 | |
3ed7a470 | 97 | if (!shost->ehandler) |
1da177e4 LT |
98 | return 0; |
99 | ||
100 | spin_lock_irqsave(shost->host_lock, flags); | |
939647ee JB |
101 | if (scsi_host_set_state(shost, SHOST_RECOVERY)) |
102 | if (scsi_host_set_state(shost, SHOST_CANCEL_RECOVERY)) | |
103 | goto out_unlock; | |
1da177e4 | 104 | |
939647ee | 105 | ret = 1; |
3111b0d1 | 106 | scmd->eh_eflags |= eh_flag; |
1da177e4 | 107 | list_add_tail(&scmd->eh_entry, &shost->eh_cmd_q); |
1da177e4 LT |
108 | shost->host_failed++; |
109 | scsi_eh_wakeup(shost); | |
939647ee | 110 | out_unlock: |
1da177e4 | 111 | spin_unlock_irqrestore(shost->host_lock, flags); |
939647ee | 112 | return ret; |
1da177e4 LT |
113 | } |
114 | ||
115 | /** | |
116 | * scsi_add_timer - Start timeout timer for a single scsi command. | |
117 | * @scmd: scsi command that is about to start running. | |
118 | * @timeout: amount of time to allow this command to run. | |
119 | * @complete: timeout function to call if timer isn't canceled. | |
120 | * | |
121 | * Notes: | |
122 | * This should be turned into an inline function. Each scsi command | |
123 | * has its own timer, and as it is added to the queue, we set up the | |
124 | * timer. When the command completes, we cancel the timer. | |
125 | **/ | |
126 | void scsi_add_timer(struct scsi_cmnd *scmd, int timeout, | |
127 | void (*complete)(struct scsi_cmnd *)) | |
128 | { | |
129 | ||
130 | /* | |
131 | * If the clock was already running for this command, then | |
132 | * first delete the timer. The timer handling code gets rather | |
133 | * confused if we don't do this. | |
134 | */ | |
135 | if (scmd->eh_timeout.function) | |
136 | del_timer(&scmd->eh_timeout); | |
137 | ||
138 | scmd->eh_timeout.data = (unsigned long)scmd; | |
139 | scmd->eh_timeout.expires = jiffies + timeout; | |
140 | scmd->eh_timeout.function = (void (*)(unsigned long)) complete; | |
141 | ||
142 | SCSI_LOG_ERROR_RECOVERY(5, printk("%s: scmd: %p, time:" | |
143 | " %d, (%p)\n", __FUNCTION__, | |
144 | scmd, timeout, complete)); | |
145 | ||
146 | add_timer(&scmd->eh_timeout); | |
147 | } | |
1da177e4 LT |
148 | |
149 | /** | |
150 | * scsi_delete_timer - Delete/cancel timer for a given function. | |
151 | * @scmd: Cmd that we are canceling timer for | |
152 | * | |
153 | * Notes: | |
154 | * This should be turned into an inline function. | |
155 | * | |
156 | * Return value: | |
157 | * 1 if we were able to detach the timer. 0 if we blew it, and the | |
158 | * timer function has already started to run. | |
159 | **/ | |
160 | int scsi_delete_timer(struct scsi_cmnd *scmd) | |
161 | { | |
162 | int rtn; | |
163 | ||
164 | rtn = del_timer(&scmd->eh_timeout); | |
165 | ||
166 | SCSI_LOG_ERROR_RECOVERY(5, printk("%s: scmd: %p," | |
167 | " rtn: %d\n", __FUNCTION__, | |
168 | scmd, rtn)); | |
169 | ||
170 | scmd->eh_timeout.data = (unsigned long)NULL; | |
171 | scmd->eh_timeout.function = NULL; | |
172 | ||
173 | return rtn; | |
174 | } | |
1da177e4 LT |
175 | |
176 | /** | |
177 | * scsi_times_out - Timeout function for normal scsi commands. | |
178 | * @scmd: Cmd that is timing out. | |
179 | * | |
180 | * Notes: | |
181 | * We do not need to lock this. There is the potential for a race | |
182 | * only in that the normal completion handling might run, but if the | |
183 | * normal completion function determines that the timer has already | |
184 | * fired, then it mustn't do anything. | |
185 | **/ | |
186 | void scsi_times_out(struct scsi_cmnd *scmd) | |
187 | { | |
6c5f8ce1 JB |
188 | enum scsi_eh_timer_return (* eh_timed_out)(struct scsi_cmnd *); |
189 | ||
1da177e4 LT |
190 | scsi_log_completion(scmd, TIMEOUT_ERROR); |
191 | ||
c829c394 | 192 | if (scmd->device->host->transportt->eh_timed_out) |
6c5f8ce1 JB |
193 | eh_timed_out = scmd->device->host->transportt->eh_timed_out; |
194 | else if (scmd->device->host->hostt->eh_timed_out) | |
195 | eh_timed_out = scmd->device->host->hostt->eh_timed_out; | |
196 | else | |
197 | eh_timed_out = NULL; | |
198 | ||
199 | if (eh_timed_out) | |
200 | switch (eh_timed_out(scmd)) { | |
1da177e4 LT |
201 | case EH_HANDLED: |
202 | __scsi_done(scmd); | |
203 | return; | |
204 | case EH_RESET_TIMER: | |
1da177e4 LT |
205 | scsi_add_timer(scmd, scmd->timeout_per_command, |
206 | scsi_times_out); | |
207 | return; | |
208 | case EH_NOT_HANDLED: | |
209 | break; | |
210 | } | |
211 | ||
212 | if (unlikely(!scsi_eh_scmd_add(scmd, SCSI_EH_CANCEL_CMD))) { | |
939647ee JB |
213 | scmd->result |= DID_TIME_OUT << 16; |
214 | __scsi_done(scmd); | |
1da177e4 LT |
215 | } |
216 | } | |
217 | ||
218 | /** | |
219 | * scsi_block_when_processing_errors - Prevent cmds from being queued. | |
220 | * @sdev: Device on which we are performing recovery. | |
221 | * | |
222 | * Description: | |
223 | * We block until the host is out of error recovery, and then check to | |
224 | * see whether the host or the device is offline. | |
225 | * | |
226 | * Return value: | |
227 | * 0 when dev was taken offline by error recovery. 1 OK to proceed. | |
228 | **/ | |
229 | int scsi_block_when_processing_errors(struct scsi_device *sdev) | |
230 | { | |
231 | int online; | |
232 | ||
939647ee | 233 | wait_event(sdev->host->host_wait, !scsi_host_in_recovery(sdev->host)); |
1da177e4 LT |
234 | |
235 | online = scsi_device_online(sdev); | |
236 | ||
237 | SCSI_LOG_ERROR_RECOVERY(5, printk("%s: rtn: %d\n", __FUNCTION__, | |
238 | online)); | |
239 | ||
240 | return online; | |
241 | } | |
242 | EXPORT_SYMBOL(scsi_block_when_processing_errors); | |
243 | ||
244 | #ifdef CONFIG_SCSI_LOGGING | |
245 | /** | |
246 | * scsi_eh_prt_fail_stats - Log info on failures. | |
247 | * @shost: scsi host being recovered. | |
248 | * @work_q: Queue of scsi cmds to process. | |
249 | **/ | |
250 | static inline void scsi_eh_prt_fail_stats(struct Scsi_Host *shost, | |
251 | struct list_head *work_q) | |
252 | { | |
253 | struct scsi_cmnd *scmd; | |
254 | struct scsi_device *sdev; | |
255 | int total_failures = 0; | |
256 | int cmd_failed = 0; | |
257 | int cmd_cancel = 0; | |
258 | int devices_failed = 0; | |
259 | ||
260 | shost_for_each_device(sdev, shost) { | |
261 | list_for_each_entry(scmd, work_q, eh_entry) { | |
262 | if (scmd->device == sdev) { | |
263 | ++total_failures; | |
3111b0d1 | 264 | if (scmd->eh_eflags & SCSI_EH_CANCEL_CMD) |
1da177e4 LT |
265 | ++cmd_cancel; |
266 | else | |
267 | ++cmd_failed; | |
268 | } | |
269 | } | |
270 | ||
271 | if (cmd_cancel || cmd_failed) { | |
272 | SCSI_LOG_ERROR_RECOVERY(3, | |
9ccfc756 JB |
273 | sdev_printk(KERN_INFO, sdev, |
274 | "%s: cmds failed: %d, cancel: %d\n", | |
275 | __FUNCTION__, cmd_failed, | |
276 | cmd_cancel)); | |
1da177e4 LT |
277 | cmd_cancel = 0; |
278 | cmd_failed = 0; | |
279 | ++devices_failed; | |
280 | } | |
281 | } | |
282 | ||
283 | SCSI_LOG_ERROR_RECOVERY(2, printk("Total of %d commands on %d" | |
284 | " devices require eh work\n", | |
285 | total_failures, devices_failed)); | |
286 | } | |
287 | #endif | |
288 | ||
289 | /** | |
290 | * scsi_check_sense - Examine scsi cmd sense | |
291 | * @scmd: Cmd to have sense checked. | |
292 | * | |
293 | * Return value: | |
294 | * SUCCESS or FAILED or NEEDS_RETRY | |
295 | * | |
296 | * Notes: | |
297 | * When a deferred error is detected the current command has | |
298 | * not been executed and needs retrying. | |
299 | **/ | |
300 | static int scsi_check_sense(struct scsi_cmnd *scmd) | |
301 | { | |
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 | ||
310 | /* | |
311 | * Previous logic looked for FILEMARK, EOM or ILI which are | |
312 | * mainly associated with tapes and returned SUCCESS. | |
313 | */ | |
314 | if (sshdr.response_code == 0x70) { | |
315 | /* fixed format */ | |
316 | if (scmd->sense_buffer[2] & 0xe0) | |
317 | return SUCCESS; | |
318 | } else { | |
319 | /* | |
320 | * descriptor format: look for "stream commands sense data | |
321 | * descriptor" (see SSC-3). Assume single sense data | |
322 | * descriptor. Ignore ILI from SBC-2 READ LONG and WRITE LONG. | |
323 | */ | |
324 | if ((sshdr.additional_length > 3) && | |
325 | (scmd->sense_buffer[8] == 0x4) && | |
326 | (scmd->sense_buffer[11] & 0xe0)) | |
327 | return SUCCESS; | |
328 | } | |
329 | ||
330 | switch (sshdr.sense_key) { | |
331 | case NO_SENSE: | |
332 | return SUCCESS; | |
333 | case RECOVERED_ERROR: | |
334 | return /* soft_error */ SUCCESS; | |
335 | ||
336 | case ABORTED_COMMAND: | |
337 | return NEEDS_RETRY; | |
338 | case NOT_READY: | |
339 | case UNIT_ATTENTION: | |
340 | /* | |
341 | * if we are expecting a cc/ua because of a bus reset that we | |
342 | * performed, treat this just as a retry. otherwise this is | |
343 | * information that we should pass up to the upper-level driver | |
344 | * so that we can deal with it there. | |
345 | */ | |
346 | if (scmd->device->expecting_cc_ua) { | |
347 | scmd->device->expecting_cc_ua = 0; | |
348 | return NEEDS_RETRY; | |
349 | } | |
350 | /* | |
351 | * if the device is in the process of becoming ready, we | |
352 | * should retry. | |
353 | */ | |
354 | if ((sshdr.asc == 0x04) && (sshdr.ascq == 0x01)) | |
355 | return NEEDS_RETRY; | |
356 | /* | |
357 | * if the device is not started, we need to wake | |
358 | * the error handler to start the motor | |
359 | */ | |
360 | if (scmd->device->allow_restart && | |
361 | (sshdr.asc == 0x04) && (sshdr.ascq == 0x02)) | |
362 | return FAILED; | |
363 | return SUCCESS; | |
364 | ||
365 | /* these three are not supported */ | |
366 | case COPY_ABORTED: | |
367 | case VOLUME_OVERFLOW: | |
368 | case MISCOMPARE: | |
369 | return SUCCESS; | |
370 | ||
371 | case MEDIUM_ERROR: | |
fd1b494d LT |
372 | if (sshdr.asc == 0x11 || /* UNRECOVERED READ ERR */ |
373 | sshdr.asc == 0x13 || /* AMNF DATA FIELD */ | |
374 | sshdr.asc == 0x14) { /* RECORD NOT FOUND */ | |
375 | return SUCCESS; | |
376 | } | |
1da177e4 LT |
377 | return NEEDS_RETRY; |
378 | ||
379 | case HARDWARE_ERROR: | |
380 | if (scmd->device->retry_hwerror) | |
381 | return NEEDS_RETRY; | |
382 | else | |
383 | return SUCCESS; | |
384 | ||
385 | case ILLEGAL_REQUEST: | |
386 | case BLANK_CHECK: | |
387 | case DATA_PROTECT: | |
388 | default: | |
389 | return SUCCESS; | |
390 | } | |
391 | } | |
392 | ||
393 | /** | |
394 | * scsi_eh_completed_normally - Disposition a eh cmd on return from LLD. | |
395 | * @scmd: SCSI cmd to examine. | |
396 | * | |
397 | * Notes: | |
398 | * This is *only* called when we are examining the status of commands | |
399 | * queued during error recovery. the main difference here is that we | |
400 | * don't allow for the possibility of retries here, and we are a lot | |
401 | * more restrictive about what we consider acceptable. | |
402 | **/ | |
403 | static int scsi_eh_completed_normally(struct scsi_cmnd *scmd) | |
404 | { | |
405 | /* | |
406 | * first check the host byte, to see if there is anything in there | |
407 | * that would indicate what we need to do. | |
408 | */ | |
409 | if (host_byte(scmd->result) == DID_RESET) { | |
410 | /* | |
411 | * rats. we are already in the error handler, so we now | |
412 | * get to try and figure out what to do next. if the sense | |
413 | * is valid, we have a pretty good idea of what to do. | |
414 | * if not, we mark it as FAILED. | |
415 | */ | |
416 | return scsi_check_sense(scmd); | |
417 | } | |
418 | if (host_byte(scmd->result) != DID_OK) | |
419 | return FAILED; | |
420 | ||
421 | /* | |
422 | * next, check the message byte. | |
423 | */ | |
424 | if (msg_byte(scmd->result) != COMMAND_COMPLETE) | |
425 | return FAILED; | |
426 | ||
427 | /* | |
428 | * now, check the status byte to see if this indicates | |
429 | * anything special. | |
430 | */ | |
431 | switch (status_byte(scmd->result)) { | |
432 | case GOOD: | |
433 | case COMMAND_TERMINATED: | |
434 | return SUCCESS; | |
435 | case CHECK_CONDITION: | |
436 | return scsi_check_sense(scmd); | |
437 | case CONDITION_GOOD: | |
438 | case INTERMEDIATE_GOOD: | |
439 | case INTERMEDIATE_C_GOOD: | |
440 | /* | |
441 | * who knows? FIXME(eric) | |
442 | */ | |
443 | return SUCCESS; | |
444 | case BUSY: | |
445 | case QUEUE_FULL: | |
446 | case RESERVATION_CONFLICT: | |
447 | default: | |
448 | return FAILED; | |
449 | } | |
450 | return FAILED; | |
451 | } | |
452 | ||
1da177e4 LT |
453 | /** |
454 | * scsi_eh_done - Completion function for error handling. | |
455 | * @scmd: Cmd that is done. | |
456 | **/ | |
457 | static void scsi_eh_done(struct scsi_cmnd *scmd) | |
458 | { | |
85631672 MR |
459 | struct completion *eh_action; |
460 | ||
7dfdc9a5 CH |
461 | SCSI_LOG_ERROR_RECOVERY(3, |
462 | printk("%s scmd: %p result: %x\n", | |
463 | __FUNCTION__, scmd, scmd->result)); | |
85631672 MR |
464 | |
465 | eh_action = scmd->device->host->eh_action; | |
466 | if (eh_action) | |
467 | complete(eh_action); | |
1da177e4 LT |
468 | } |
469 | ||
292148f8 BK |
470 | /** |
471 | * scsi_try_host_reset - ask host adapter to reset itself | |
472 | * @scmd: SCSI cmd to send hsot reset. | |
473 | **/ | |
474 | static int scsi_try_host_reset(struct scsi_cmnd *scmd) | |
475 | { | |
476 | unsigned long flags; | |
477 | int rtn; | |
478 | ||
479 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Snd Host RST\n", | |
480 | __FUNCTION__)); | |
481 | ||
482 | if (!scmd->device->host->hostt->eh_host_reset_handler) | |
483 | return FAILED; | |
484 | ||
485 | rtn = scmd->device->host->hostt->eh_host_reset_handler(scmd); | |
486 | ||
487 | if (rtn == SUCCESS) { | |
488 | if (!scmd->device->host->hostt->skip_settle_delay) | |
489 | ssleep(HOST_RESET_SETTLE_TIME); | |
490 | spin_lock_irqsave(scmd->device->host->host_lock, flags); | |
491 | scsi_report_bus_reset(scmd->device->host, | |
492 | scmd_channel(scmd)); | |
493 | spin_unlock_irqrestore(scmd->device->host->host_lock, flags); | |
494 | } | |
495 | ||
496 | return rtn; | |
497 | } | |
498 | ||
499 | /** | |
500 | * scsi_try_bus_reset - ask host to perform a bus reset | |
501 | * @scmd: SCSI cmd to send bus reset. | |
502 | **/ | |
503 | static int scsi_try_bus_reset(struct scsi_cmnd *scmd) | |
504 | { | |
505 | unsigned long flags; | |
506 | int rtn; | |
507 | ||
508 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Snd Bus RST\n", | |
509 | __FUNCTION__)); | |
510 | ||
511 | if (!scmd->device->host->hostt->eh_bus_reset_handler) | |
512 | return FAILED; | |
513 | ||
514 | rtn = scmd->device->host->hostt->eh_bus_reset_handler(scmd); | |
515 | ||
516 | if (rtn == SUCCESS) { | |
517 | if (!scmd->device->host->hostt->skip_settle_delay) | |
518 | ssleep(BUS_RESET_SETTLE_TIME); | |
519 | spin_lock_irqsave(scmd->device->host->host_lock, flags); | |
520 | scsi_report_bus_reset(scmd->device->host, | |
521 | scmd_channel(scmd)); | |
522 | spin_unlock_irqrestore(scmd->device->host->host_lock, flags); | |
523 | } | |
524 | ||
525 | return rtn; | |
526 | } | |
527 | ||
528 | /** | |
529 | * scsi_try_bus_device_reset - Ask host to perform a BDR on a dev | |
530 | * @scmd: SCSI cmd used to send BDR | |
531 | * | |
532 | * Notes: | |
533 | * There is no timeout for this operation. if this operation is | |
534 | * unreliable for a given host, then the host itself needs to put a | |
535 | * timer on it, and set the host back to a consistent state prior to | |
536 | * returning. | |
537 | **/ | |
538 | static int scsi_try_bus_device_reset(struct scsi_cmnd *scmd) | |
539 | { | |
540 | int rtn; | |
541 | ||
542 | if (!scmd->device->host->hostt->eh_device_reset_handler) | |
543 | return FAILED; | |
544 | ||
545 | rtn = scmd->device->host->hostt->eh_device_reset_handler(scmd); | |
546 | if (rtn == SUCCESS) { | |
547 | scmd->device->was_reset = 1; | |
548 | scmd->device->expecting_cc_ua = 1; | |
549 | } | |
550 | ||
551 | return rtn; | |
552 | } | |
553 | ||
554 | static int __scsi_try_to_abort_cmd(struct scsi_cmnd *scmd) | |
555 | { | |
556 | if (!scmd->device->host->hostt->eh_abort_handler) | |
557 | return FAILED; | |
558 | ||
559 | return scmd->device->host->hostt->eh_abort_handler(scmd); | |
560 | } | |
561 | ||
562 | /** | |
563 | * scsi_try_to_abort_cmd - Ask host to abort a running command. | |
564 | * @scmd: SCSI cmd to abort from Lower Level. | |
565 | * | |
566 | * Notes: | |
567 | * This function will not return until the user's completion function | |
568 | * has been called. there is no timeout on this operation. if the | |
569 | * author of the low-level driver wishes this operation to be timed, | |
570 | * they can provide this facility themselves. helper functions in | |
571 | * scsi_error.c can be supplied to make this easier to do. | |
572 | **/ | |
573 | static int scsi_try_to_abort_cmd(struct scsi_cmnd *scmd) | |
574 | { | |
575 | /* | |
576 | * scsi_done was called just after the command timed out and before | |
577 | * we had a chance to process it. (db) | |
578 | */ | |
579 | if (scmd->serial_number == 0) | |
580 | return SUCCESS; | |
581 | return __scsi_try_to_abort_cmd(scmd); | |
582 | } | |
583 | ||
584 | static void scsi_abort_eh_cmnd(struct scsi_cmnd *scmd) | |
585 | { | |
586 | if (__scsi_try_to_abort_cmd(scmd) != SUCCESS) | |
587 | if (scsi_try_bus_device_reset(scmd) != SUCCESS) | |
588 | if (scsi_try_bus_reset(scmd) != SUCCESS) | |
589 | scsi_try_host_reset(scmd); | |
590 | } | |
591 | ||
1da177e4 | 592 | /** |
2dc611de CH |
593 | * scsi_send_eh_cmnd - submit a scsi command as part of error recory |
594 | * @scmd: SCSI command structure to hijack | |
55db6c1b | 595 | * @cmnd: CDB to send. Can be NULL if no new cmnd is needed |
2dc611de CH |
596 | * @cmnd_size: size in bytes of @cmnd |
597 | * @timeout: timeout for this request | |
55db6c1b | 598 | * @sense_bytes: size of sense data to copy. or 0 (if != 0 @cmnd is ignored) |
2dc611de CH |
599 | * |
600 | * This function is used to send a scsi command down to a target device | |
55db6c1b BH |
601 | * as part of the error recovery process. If @sense_bytes is 0 the command |
602 | * sent must be one that does not transfer any data. If @sense_bytes != 0 | |
603 | * @cmnd is ignored and this functions sets up a REQUEST_SENSE command | |
604 | * and cmnd buffers to read @sense_bytes into @scmd->sense_buffer. | |
1da177e4 | 605 | * |
1da177e4 LT |
606 | * Return value: |
607 | * SUCCESS or FAILED or NEEDS_RETRY | |
608 | **/ | |
0db99e33 | 609 | static int scsi_send_eh_cmnd(struct scsi_cmnd *scmd, unsigned char *cmnd, |
55db6c1b | 610 | int cmnd_size, int timeout, unsigned sense_bytes) |
1da177e4 | 611 | { |
f59114b7 | 612 | struct scsi_device *sdev = scmd->device; |
613 | struct Scsi_Host *shost = sdev->host; | |
7fbb3645 | 614 | DECLARE_COMPLETION_ONSTACK(done); |
7dfdc9a5 | 615 | unsigned long timeleft; |
1da177e4 | 616 | unsigned long flags; |
55db6c1b BH |
617 | |
618 | unsigned char old_cmd_len; | |
631c228c CH |
619 | unsigned char old_cmnd[MAX_COMMAND_SIZE]; |
620 | enum dma_data_direction old_data_direction; | |
631c228c CH |
621 | unsigned old_bufflen; |
622 | void *old_buffer; | |
55db6c1b BH |
623 | unsigned short old_use_sg; |
624 | int old_resid; | |
625 | int old_result; | |
626 | ||
627 | struct scatterlist sgl; | |
7dfdc9a5 | 628 | int rtn; |
1da177e4 | 629 | |
631c228c CH |
630 | /* |
631 | * We need saved copies of a number of fields - this is because | |
632 | * error handling may need to overwrite these with different values | |
633 | * to run different commands, and once error handling is complete, | |
634 | * we will need to restore these values prior to running the actual | |
635 | * command. | |
636 | */ | |
55db6c1b | 637 | old_cmd_len = scmd->cmd_len; |
631c228c CH |
638 | memcpy(old_cmnd, scmd->cmnd, sizeof(scmd->cmnd)); |
639 | old_data_direction = scmd->sc_data_direction; | |
55db6c1b BH |
640 | old_bufflen = scmd->request_bufflen; |
641 | old_buffer = scmd->request_buffer; | |
631c228c | 642 | old_use_sg = scmd->use_sg; |
55db6c1b BH |
643 | old_resid = scmd->resid; |
644 | old_result = scmd->result; | |
631c228c | 645 | |
55db6c1b BH |
646 | if (sense_bytes) { |
647 | scmd->request_bufflen = min_t(unsigned, | |
648 | sizeof(scmd->sense_buffer), sense_bytes); | |
649 | sg_init_one(&sgl, scmd->sense_buffer, scmd->request_bufflen); | |
2dc611de | 650 | scmd->request_buffer = &sgl; |
55db6c1b | 651 | scmd->sc_data_direction = DMA_FROM_DEVICE; |
2dc611de | 652 | scmd->use_sg = 1; |
55db6c1b BH |
653 | memset(scmd->cmnd, 0, sizeof(scmd->cmnd)); |
654 | scmd->cmnd[0] = REQUEST_SENSE; | |
655 | scmd->cmnd[4] = scmd->request_bufflen; | |
656 | scmd->cmd_len = COMMAND_SIZE(scmd->cmnd[0]); | |
631c228c CH |
657 | } else { |
658 | scmd->request_buffer = NULL; | |
659 | scmd->request_bufflen = 0; | |
660 | scmd->sc_data_direction = DMA_NONE; | |
2dc611de | 661 | scmd->use_sg = 0; |
55db6c1b BH |
662 | if (cmnd) { |
663 | memset(scmd->cmnd, 0, sizeof(scmd->cmnd)); | |
664 | memcpy(scmd->cmnd, cmnd, cmnd_size); | |
665 | scmd->cmd_len = COMMAND_SIZE(scmd->cmnd[0]); | |
666 | } | |
631c228c CH |
667 | } |
668 | ||
669 | scmd->underflow = 0; | |
631c228c | 670 | |
55db6c1b | 671 | if (sdev->scsi_level <= SCSI_2 && sdev->scsi_level != SCSI_UNKNOWN) |
1da177e4 | 672 | scmd->cmnd[1] = (scmd->cmnd[1] & 0x1f) | |
f59114b7 | 673 | (sdev->lun << 5 & 0xe0); |
1da177e4 | 674 | |
631c228c CH |
675 | /* |
676 | * Zero the sense buffer. The scsi spec mandates that any | |
677 | * untransferred sense data should be interpreted as being zero. | |
678 | */ | |
679 | memset(scmd->sense_buffer, 0, sizeof(scmd->sense_buffer)); | |
680 | ||
7dfdc9a5 | 681 | shost->eh_action = &done; |
1da177e4 | 682 | |
f59114b7 | 683 | spin_lock_irqsave(shost->host_lock, flags); |
1da177e4 | 684 | scsi_log_send(scmd); |
f59114b7 | 685 | shost->hostt->queuecommand(scmd, scsi_eh_done); |
686 | spin_unlock_irqrestore(shost->host_lock, flags); | |
1da177e4 | 687 | |
7dfdc9a5 | 688 | timeleft = wait_for_completion_timeout(&done, timeout); |
1da177e4 | 689 | |
f59114b7 | 690 | shost->eh_action = NULL; |
1da177e4 | 691 | |
7dfdc9a5 | 692 | scsi_log_completion(scmd, SUCCESS); |
1da177e4 | 693 | |
7dfdc9a5 CH |
694 | SCSI_LOG_ERROR_RECOVERY(3, |
695 | printk("%s: scmd: %p, timeleft: %ld\n", | |
696 | __FUNCTION__, scmd, timeleft)); | |
1da177e4 LT |
697 | |
698 | /* | |
7dfdc9a5 CH |
699 | * If there is time left scsi_eh_done got called, and we will |
700 | * examine the actual status codes to see whether the command | |
701 | * actually did complete normally, else tell the host to forget | |
702 | * about this command. | |
1da177e4 | 703 | */ |
7dfdc9a5 | 704 | if (timeleft) { |
1da177e4 LT |
705 | rtn = scsi_eh_completed_normally(scmd); |
706 | SCSI_LOG_ERROR_RECOVERY(3, | |
707 | printk("%s: scsi_eh_completed_normally %x\n", | |
708 | __FUNCTION__, rtn)); | |
7dfdc9a5 | 709 | |
1da177e4 LT |
710 | switch (rtn) { |
711 | case SUCCESS: | |
712 | case NEEDS_RETRY: | |
713 | case FAILED: | |
714 | break; | |
715 | default: | |
716 | rtn = FAILED; | |
717 | break; | |
718 | } | |
7dfdc9a5 | 719 | } else { |
292148f8 | 720 | scsi_abort_eh_cmnd(scmd); |
7dfdc9a5 | 721 | rtn = FAILED; |
1da177e4 LT |
722 | } |
723 | ||
631c228c | 724 | |
631c228c CH |
725 | /* |
726 | * Restore original data | |
727 | */ | |
55db6c1b | 728 | scmd->cmd_len = old_cmd_len; |
631c228c CH |
729 | memcpy(scmd->cmnd, old_cmnd, sizeof(scmd->cmnd)); |
730 | scmd->sc_data_direction = old_data_direction; | |
55db6c1b BH |
731 | scmd->request_bufflen = old_bufflen; |
732 | scmd->request_buffer = old_buffer; | |
631c228c | 733 | scmd->use_sg = old_use_sg; |
55db6c1b | 734 | scmd->resid = old_resid; |
631c228c | 735 | scmd->result = old_result; |
1da177e4 LT |
736 | return rtn; |
737 | } | |
738 | ||
739 | /** | |
740 | * scsi_request_sense - Request sense data from a particular target. | |
741 | * @scmd: SCSI cmd for request sense. | |
742 | * | |
743 | * Notes: | |
744 | * Some hosts automatically obtain this information, others require | |
745 | * that we obtain it on our own. This function will *not* return until | |
746 | * the command either times out, or it completes. | |
747 | **/ | |
748 | static int scsi_request_sense(struct scsi_cmnd *scmd) | |
749 | { | |
55db6c1b | 750 | return scsi_send_eh_cmnd(scmd, NULL, 0, SENSE_TIMEOUT, ~0); |
1da177e4 LT |
751 | } |
752 | ||
753 | /** | |
754 | * scsi_eh_finish_cmd - Handle a cmd that eh is finished with. | |
755 | * @scmd: Original SCSI cmd that eh has finished. | |
756 | * @done_q: Queue for processed commands. | |
757 | * | |
758 | * Notes: | |
759 | * We don't want to use the normal command completion while we are are | |
760 | * still handling errors - it may cause other commands to be queued, | |
761 | * and that would disturb what we are doing. thus we really want to | |
762 | * keep a list of pending commands for final completion, and once we | |
763 | * are ready to leave error handling we handle completion for real. | |
764 | **/ | |
041c5fc3 | 765 | void scsi_eh_finish_cmd(struct scsi_cmnd *scmd, struct list_head *done_q) |
1da177e4 LT |
766 | { |
767 | scmd->device->host->host_failed--; | |
3111b0d1 | 768 | scmd->eh_eflags = 0; |
1da177e4 LT |
769 | list_move_tail(&scmd->eh_entry, done_q); |
770 | } | |
041c5fc3 | 771 | EXPORT_SYMBOL(scsi_eh_finish_cmd); |
1da177e4 LT |
772 | |
773 | /** | |
774 | * scsi_eh_get_sense - Get device sense data. | |
775 | * @work_q: Queue of commands to process. | |
776 | * @done_q: Queue of proccessed commands.. | |
777 | * | |
778 | * Description: | |
779 | * See if we need to request sense information. if so, then get it | |
780 | * now, so we have a better idea of what to do. | |
781 | * | |
782 | * Notes: | |
783 | * This has the unfortunate side effect that if a shost adapter does | |
784 | * not automatically request sense information, that we end up shutting | |
785 | * it down before we request it. | |
786 | * | |
787 | * All drivers should request sense information internally these days, | |
788 | * so for now all I have to say is tough noogies if you end up in here. | |
789 | * | |
790 | * XXX: Long term this code should go away, but that needs an audit of | |
791 | * all LLDDs first. | |
792 | **/ | |
dca84e46 DW |
793 | int scsi_eh_get_sense(struct list_head *work_q, |
794 | struct list_head *done_q) | |
1da177e4 | 795 | { |
937abeaa | 796 | struct scsi_cmnd *scmd, *next; |
1da177e4 LT |
797 | int rtn; |
798 | ||
937abeaa | 799 | list_for_each_entry_safe(scmd, next, work_q, eh_entry) { |
3111b0d1 | 800 | if ((scmd->eh_eflags & SCSI_EH_CANCEL_CMD) || |
1da177e4 LT |
801 | SCSI_SENSE_VALID(scmd)) |
802 | continue; | |
803 | ||
3bf743e7 JG |
804 | SCSI_LOG_ERROR_RECOVERY(2, scmd_printk(KERN_INFO, scmd, |
805 | "%s: requesting sense\n", | |
806 | current->comm)); | |
1da177e4 LT |
807 | rtn = scsi_request_sense(scmd); |
808 | if (rtn != SUCCESS) | |
809 | continue; | |
810 | ||
811 | SCSI_LOG_ERROR_RECOVERY(3, printk("sense requested for %p" | |
812 | " result %x\n", scmd, | |
813 | scmd->result)); | |
814 | SCSI_LOG_ERROR_RECOVERY(3, scsi_print_sense("bh", scmd)); | |
815 | ||
816 | rtn = scsi_decide_disposition(scmd); | |
817 | ||
818 | /* | |
819 | * if the result was normal, then just pass it along to the | |
820 | * upper level. | |
821 | */ | |
822 | if (rtn == SUCCESS) | |
823 | /* we don't want this command reissued, just | |
824 | * finished with the sense data, so set | |
825 | * retries to the max allowed to ensure it | |
826 | * won't get reissued */ | |
827 | scmd->retries = scmd->allowed; | |
828 | else if (rtn != NEEDS_RETRY) | |
829 | continue; | |
830 | ||
831 | scsi_eh_finish_cmd(scmd, done_q); | |
832 | } | |
833 | ||
834 | return list_empty(work_q); | |
835 | } | |
dca84e46 | 836 | EXPORT_SYMBOL_GPL(scsi_eh_get_sense); |
1da177e4 | 837 | |
1da177e4 LT |
838 | /** |
839 | * scsi_eh_tur - Send TUR to device. | |
840 | * @scmd: Scsi cmd to send TUR | |
841 | * | |
842 | * Return value: | |
843 | * 0 - Device is ready. 1 - Device NOT ready. | |
844 | **/ | |
845 | static int scsi_eh_tur(struct scsi_cmnd *scmd) | |
846 | { | |
847 | static unsigned char tur_command[6] = {TEST_UNIT_READY, 0, 0, 0, 0, 0}; | |
848 | int retry_cnt = 1, rtn; | |
849 | ||
850 | retry_tur: | |
0db99e33 | 851 | rtn = scsi_send_eh_cmnd(scmd, tur_command, 6, SENSE_TIMEOUT, 0); |
1da177e4 | 852 | |
1da177e4 LT |
853 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: scmd %p rtn %x\n", |
854 | __FUNCTION__, scmd, rtn)); | |
631c228c CH |
855 | |
856 | switch (rtn) { | |
857 | case NEEDS_RETRY: | |
1da177e4 LT |
858 | if (retry_cnt--) |
859 | goto retry_tur; | |
631c228c CH |
860 | /*FALLTHRU*/ |
861 | case SUCCESS: | |
e47373ec | 862 | return 0; |
631c228c CH |
863 | default: |
864 | return 1; | |
e47373ec | 865 | } |
1da177e4 LT |
866 | } |
867 | ||
868 | /** | |
869 | * scsi_eh_abort_cmds - abort canceled commands. | |
870 | * @shost: scsi host being recovered. | |
871 | * @eh_done_q: list_head for processed commands. | |
872 | * | |
873 | * Decription: | |
874 | * Try and see whether or not it makes sense to try and abort the | |
875 | * running command. this only works out to be the case if we have one | |
876 | * command that has timed out. if the command simply failed, it makes | |
877 | * no sense to try and abort the command, since as far as the shost | |
878 | * adapter is concerned, it isn't running. | |
879 | **/ | |
880 | static int scsi_eh_abort_cmds(struct list_head *work_q, | |
881 | struct list_head *done_q) | |
882 | { | |
937abeaa | 883 | struct scsi_cmnd *scmd, *next; |
1da177e4 LT |
884 | int rtn; |
885 | ||
937abeaa | 886 | list_for_each_entry_safe(scmd, next, work_q, eh_entry) { |
3111b0d1 | 887 | if (!(scmd->eh_eflags & SCSI_EH_CANCEL_CMD)) |
1da177e4 LT |
888 | continue; |
889 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: aborting cmd:" | |
890 | "0x%p\n", current->comm, | |
891 | scmd)); | |
892 | rtn = scsi_try_to_abort_cmd(scmd); | |
893 | if (rtn == SUCCESS) { | |
3111b0d1 | 894 | scmd->eh_eflags &= ~SCSI_EH_CANCEL_CMD; |
1da177e4 LT |
895 | if (!scsi_device_online(scmd->device) || |
896 | !scsi_eh_tur(scmd)) { | |
897 | scsi_eh_finish_cmd(scmd, done_q); | |
898 | } | |
899 | ||
900 | } else | |
901 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: aborting" | |
902 | " cmd failed:" | |
903 | "0x%p\n", | |
904 | current->comm, | |
905 | scmd)); | |
906 | } | |
907 | ||
908 | return list_empty(work_q); | |
909 | } | |
910 | ||
1da177e4 LT |
911 | /** |
912 | * scsi_eh_try_stu - Send START_UNIT to device. | |
913 | * @scmd: Scsi cmd to send START_UNIT | |
914 | * | |
915 | * Return value: | |
916 | * 0 - Device is ready. 1 - Device NOT ready. | |
917 | **/ | |
918 | static int scsi_eh_try_stu(struct scsi_cmnd *scmd) | |
919 | { | |
920 | static unsigned char stu_command[6] = {START_STOP, 0, 0, 0, 1, 0}; | |
1da177e4 | 921 | |
631c228c | 922 | if (scmd->device->allow_restart) { |
ed773e66 BK |
923 | int i, rtn = NEEDS_RETRY; |
924 | ||
925 | for (i = 0; rtn == NEEDS_RETRY && i < 2; i++) | |
926 | rtn = scsi_send_eh_cmnd(scmd, stu_command, 6, | |
e555db93 | 927 | scmd->device->timeout, 0); |
1da177e4 | 928 | |
631c228c CH |
929 | if (rtn == SUCCESS) |
930 | return 0; | |
931 | } | |
1da177e4 | 932 | |
1da177e4 LT |
933 | return 1; |
934 | } | |
935 | ||
936 | /** | |
937 | * scsi_eh_stu - send START_UNIT if needed | |
938 | * @shost: scsi host being recovered. | |
939 | * @eh_done_q: list_head for processed commands. | |
940 | * | |
941 | * Notes: | |
942 | * If commands are failing due to not ready, initializing command required, | |
943 | * try revalidating the device, which will end up sending a start unit. | |
944 | **/ | |
945 | static int scsi_eh_stu(struct Scsi_Host *shost, | |
946 | struct list_head *work_q, | |
947 | struct list_head *done_q) | |
948 | { | |
937abeaa | 949 | struct scsi_cmnd *scmd, *stu_scmd, *next; |
1da177e4 LT |
950 | struct scsi_device *sdev; |
951 | ||
952 | shost_for_each_device(sdev, shost) { | |
953 | stu_scmd = NULL; | |
954 | list_for_each_entry(scmd, work_q, eh_entry) | |
955 | if (scmd->device == sdev && SCSI_SENSE_VALID(scmd) && | |
956 | scsi_check_sense(scmd) == FAILED ) { | |
957 | stu_scmd = scmd; | |
958 | break; | |
959 | } | |
960 | ||
961 | if (!stu_scmd) | |
962 | continue; | |
963 | ||
964 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending START_UNIT to sdev:" | |
965 | " 0x%p\n", current->comm, sdev)); | |
966 | ||
967 | if (!scsi_eh_try_stu(stu_scmd)) { | |
968 | if (!scsi_device_online(sdev) || | |
969 | !scsi_eh_tur(stu_scmd)) { | |
937abeaa CH |
970 | list_for_each_entry_safe(scmd, next, |
971 | work_q, eh_entry) { | |
1da177e4 LT |
972 | if (scmd->device == sdev) |
973 | scsi_eh_finish_cmd(scmd, done_q); | |
974 | } | |
975 | } | |
976 | } else { | |
977 | SCSI_LOG_ERROR_RECOVERY(3, | |
978 | printk("%s: START_UNIT failed to sdev:" | |
979 | " 0x%p\n", current->comm, sdev)); | |
980 | } | |
981 | } | |
982 | ||
983 | return list_empty(work_q); | |
984 | } | |
985 | ||
986 | ||
987 | /** | |
988 | * scsi_eh_bus_device_reset - send bdr if needed | |
989 | * @shost: scsi host being recovered. | |
990 | * @eh_done_q: list_head for processed commands. | |
991 | * | |
992 | * Notes: | |
993 | * Try a bus device reset. still, look to see whether we have multiple | |
994 | * devices that are jammed or not - if we have multiple devices, it | |
995 | * makes no sense to try bus_device_reset - we really would need to try | |
996 | * a bus_reset instead. | |
997 | **/ | |
998 | static int scsi_eh_bus_device_reset(struct Scsi_Host *shost, | |
999 | struct list_head *work_q, | |
1000 | struct list_head *done_q) | |
1001 | { | |
937abeaa | 1002 | struct scsi_cmnd *scmd, *bdr_scmd, *next; |
1da177e4 LT |
1003 | struct scsi_device *sdev; |
1004 | int rtn; | |
1005 | ||
1006 | shost_for_each_device(sdev, shost) { | |
1007 | bdr_scmd = NULL; | |
1008 | list_for_each_entry(scmd, work_q, eh_entry) | |
1009 | if (scmd->device == sdev) { | |
1010 | bdr_scmd = scmd; | |
1011 | break; | |
1012 | } | |
1013 | ||
1014 | if (!bdr_scmd) | |
1015 | continue; | |
1016 | ||
1017 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending BDR sdev:" | |
1018 | " 0x%p\n", current->comm, | |
1019 | sdev)); | |
1020 | rtn = scsi_try_bus_device_reset(bdr_scmd); | |
1021 | if (rtn == SUCCESS) { | |
1022 | if (!scsi_device_online(sdev) || | |
1023 | !scsi_eh_tur(bdr_scmd)) { | |
937abeaa CH |
1024 | list_for_each_entry_safe(scmd, next, |
1025 | work_q, eh_entry) { | |
1da177e4 LT |
1026 | if (scmd->device == sdev) |
1027 | scsi_eh_finish_cmd(scmd, | |
1028 | done_q); | |
1029 | } | |
1030 | } | |
1031 | } else { | |
1032 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: BDR" | |
1033 | " failed sdev:" | |
1034 | "0x%p\n", | |
1035 | current->comm, | |
1036 | sdev)); | |
1037 | } | |
1038 | } | |
1039 | ||
1040 | return list_empty(work_q); | |
1041 | } | |
1042 | ||
1da177e4 LT |
1043 | /** |
1044 | * scsi_eh_bus_reset - send a bus reset | |
1045 | * @shost: scsi host being recovered. | |
1046 | * @eh_done_q: list_head for processed commands. | |
1047 | **/ | |
1048 | static int scsi_eh_bus_reset(struct Scsi_Host *shost, | |
1049 | struct list_head *work_q, | |
1050 | struct list_head *done_q) | |
1051 | { | |
937abeaa | 1052 | struct scsi_cmnd *scmd, *chan_scmd, *next; |
1da177e4 LT |
1053 | unsigned int channel; |
1054 | int rtn; | |
1055 | ||
1056 | /* | |
1057 | * we really want to loop over the various channels, and do this on | |
1058 | * a channel by channel basis. we should also check to see if any | |
1059 | * of the failed commands are on soft_reset devices, and if so, skip | |
1060 | * the reset. | |
1061 | */ | |
1062 | ||
1063 | for (channel = 0; channel <= shost->max_channel; channel++) { | |
1064 | chan_scmd = NULL; | |
1065 | list_for_each_entry(scmd, work_q, eh_entry) { | |
422c0d61 | 1066 | if (channel == scmd_channel(scmd)) { |
1da177e4 LT |
1067 | chan_scmd = scmd; |
1068 | break; | |
1069 | /* | |
1070 | * FIXME add back in some support for | |
1071 | * soft_reset devices. | |
1072 | */ | |
1073 | } | |
1074 | } | |
1075 | ||
1076 | if (!chan_scmd) | |
1077 | continue; | |
1078 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending BRST chan:" | |
1079 | " %d\n", current->comm, | |
1080 | channel)); | |
1081 | rtn = scsi_try_bus_reset(chan_scmd); | |
1082 | if (rtn == SUCCESS) { | |
937abeaa | 1083 | list_for_each_entry_safe(scmd, next, work_q, eh_entry) { |
422c0d61 | 1084 | if (channel == scmd_channel(scmd)) |
1da177e4 LT |
1085 | if (!scsi_device_online(scmd->device) || |
1086 | !scsi_eh_tur(scmd)) | |
1087 | scsi_eh_finish_cmd(scmd, | |
1088 | done_q); | |
1089 | } | |
1090 | } else { | |
1091 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: BRST" | |
1092 | " failed chan: %d\n", | |
1093 | current->comm, | |
1094 | channel)); | |
1095 | } | |
1096 | } | |
1097 | return list_empty(work_q); | |
1098 | } | |
1099 | ||
1100 | /** | |
1101 | * scsi_eh_host_reset - send a host reset | |
1102 | * @work_q: list_head for processed commands. | |
1103 | * @done_q: list_head for processed commands. | |
1104 | **/ | |
1105 | static int scsi_eh_host_reset(struct list_head *work_q, | |
1106 | struct list_head *done_q) | |
1107 | { | |
937abeaa | 1108 | struct scsi_cmnd *scmd, *next; |
1da177e4 | 1109 | int rtn; |
1da177e4 LT |
1110 | |
1111 | if (!list_empty(work_q)) { | |
1112 | scmd = list_entry(work_q->next, | |
1113 | struct scsi_cmnd, eh_entry); | |
1114 | ||
1115 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending HRST\n" | |
1116 | , current->comm)); | |
1117 | ||
1118 | rtn = scsi_try_host_reset(scmd); | |
1119 | if (rtn == SUCCESS) { | |
937abeaa | 1120 | list_for_each_entry_safe(scmd, next, work_q, eh_entry) { |
1da177e4 LT |
1121 | if (!scsi_device_online(scmd->device) || |
1122 | (!scsi_eh_try_stu(scmd) && !scsi_eh_tur(scmd)) || | |
1123 | !scsi_eh_tur(scmd)) | |
1124 | scsi_eh_finish_cmd(scmd, done_q); | |
1125 | } | |
1126 | } else { | |
1127 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: HRST" | |
1128 | " failed\n", | |
1129 | current->comm)); | |
1130 | } | |
1131 | } | |
1132 | return list_empty(work_q); | |
1133 | } | |
1134 | ||
1135 | /** | |
1136 | * scsi_eh_offline_sdevs - offline scsi devices that fail to recover | |
1137 | * @work_q: list_head for processed commands. | |
1138 | * @done_q: list_head for processed commands. | |
1139 | * | |
1140 | **/ | |
1141 | static void scsi_eh_offline_sdevs(struct list_head *work_q, | |
1142 | struct list_head *done_q) | |
1143 | { | |
937abeaa | 1144 | struct scsi_cmnd *scmd, *next; |
1da177e4 | 1145 | |
937abeaa | 1146 | list_for_each_entry_safe(scmd, next, work_q, eh_entry) { |
31765d7d MW |
1147 | sdev_printk(KERN_INFO, scmd->device, "Device offlined - " |
1148 | "not ready after error recovery\n"); | |
1da177e4 | 1149 | scsi_device_set_state(scmd->device, SDEV_OFFLINE); |
3111b0d1 | 1150 | if (scmd->eh_eflags & SCSI_EH_CANCEL_CMD) { |
1da177e4 LT |
1151 | /* |
1152 | * FIXME: Handle lost cmds. | |
1153 | */ | |
1154 | } | |
1155 | scsi_eh_finish_cmd(scmd, done_q); | |
1156 | } | |
1157 | return; | |
1158 | } | |
1159 | ||
1160 | /** | |
1161 | * scsi_decide_disposition - Disposition a cmd on return from LLD. | |
1162 | * @scmd: SCSI cmd to examine. | |
1163 | * | |
1164 | * Notes: | |
1165 | * This is *only* called when we are examining the status after sending | |
1166 | * out the actual data command. any commands that are queued for error | |
1167 | * recovery (e.g. test_unit_ready) do *not* come through here. | |
1168 | * | |
1169 | * When this routine returns failed, it means the error handler thread | |
1170 | * is woken. In cases where the error code indicates an error that | |
1171 | * doesn't require the error handler read (i.e. we don't need to | |
1172 | * abort/reset), this function should return SUCCESS. | |
1173 | **/ | |
1174 | int scsi_decide_disposition(struct scsi_cmnd *scmd) | |
1175 | { | |
1176 | int rtn; | |
1177 | ||
1178 | /* | |
1179 | * if the device is offline, then we clearly just pass the result back | |
1180 | * up to the top level. | |
1181 | */ | |
1182 | if (!scsi_device_online(scmd->device)) { | |
1183 | SCSI_LOG_ERROR_RECOVERY(5, printk("%s: device offline - report" | |
1184 | " as SUCCESS\n", | |
1185 | __FUNCTION__)); | |
1186 | return SUCCESS; | |
1187 | } | |
1188 | ||
1189 | /* | |
1190 | * first check the host byte, to see if there is anything in there | |
1191 | * that would indicate what we need to do. | |
1192 | */ | |
1193 | switch (host_byte(scmd->result)) { | |
1194 | case DID_PASSTHROUGH: | |
1195 | /* | |
1196 | * no matter what, pass this through to the upper layer. | |
1197 | * nuke this special code so that it looks like we are saying | |
1198 | * did_ok. | |
1199 | */ | |
1200 | scmd->result &= 0xff00ffff; | |
1201 | return SUCCESS; | |
1202 | case DID_OK: | |
1203 | /* | |
1204 | * looks good. drop through, and check the next byte. | |
1205 | */ | |
1206 | break; | |
1207 | case DID_NO_CONNECT: | |
1208 | case DID_BAD_TARGET: | |
1209 | case DID_ABORT: | |
1210 | /* | |
1211 | * note - this means that we just report the status back | |
1212 | * to the top level driver, not that we actually think | |
1213 | * that it indicates SUCCESS. | |
1214 | */ | |
1215 | return SUCCESS; | |
1216 | /* | |
1217 | * when the low level driver returns did_soft_error, | |
1218 | * it is responsible for keeping an internal retry counter | |
1219 | * in order to avoid endless loops (db) | |
1220 | * | |
1221 | * actually this is a bug in this function here. we should | |
1222 | * be mindful of the maximum number of retries specified | |
1223 | * and not get stuck in a loop. | |
1224 | */ | |
1225 | case DID_SOFT_ERROR: | |
1226 | goto maybe_retry; | |
1227 | case DID_IMM_RETRY: | |
1228 | return NEEDS_RETRY; | |
1229 | ||
bf341919 | 1230 | case DID_REQUEUE: |
1231 | return ADD_TO_MLQUEUE; | |
1232 | ||
1da177e4 LT |
1233 | case DID_ERROR: |
1234 | if (msg_byte(scmd->result) == COMMAND_COMPLETE && | |
1235 | status_byte(scmd->result) == RESERVATION_CONFLICT) | |
1236 | /* | |
1237 | * execute reservation conflict processing code | |
1238 | * lower down | |
1239 | */ | |
1240 | break; | |
1241 | /* fallthrough */ | |
1242 | ||
1243 | case DID_BUS_BUSY: | |
1244 | case DID_PARITY: | |
1245 | goto maybe_retry; | |
1246 | case DID_TIME_OUT: | |
1247 | /* | |
1248 | * when we scan the bus, we get timeout messages for | |
1249 | * these commands if there is no device available. | |
1250 | * other hosts report did_no_connect for the same thing. | |
1251 | */ | |
1252 | if ((scmd->cmnd[0] == TEST_UNIT_READY || | |
1253 | scmd->cmnd[0] == INQUIRY)) { | |
1254 | return SUCCESS; | |
1255 | } else { | |
1256 | return FAILED; | |
1257 | } | |
1258 | case DID_RESET: | |
1259 | return SUCCESS; | |
1260 | default: | |
1261 | return FAILED; | |
1262 | } | |
1263 | ||
1264 | /* | |
1265 | * next, check the message byte. | |
1266 | */ | |
1267 | if (msg_byte(scmd->result) != COMMAND_COMPLETE) | |
1268 | return FAILED; | |
1269 | ||
1270 | /* | |
1271 | * check the status byte to see if this indicates anything special. | |
1272 | */ | |
1273 | switch (status_byte(scmd->result)) { | |
1274 | case QUEUE_FULL: | |
1275 | /* | |
1276 | * the case of trying to send too many commands to a | |
1277 | * tagged queueing device. | |
1278 | */ | |
1279 | case BUSY: | |
1280 | /* | |
1281 | * device can't talk to us at the moment. Should only | |
1282 | * occur (SAM-3) when the task queue is empty, so will cause | |
1283 | * the empty queue handling to trigger a stall in the | |
1284 | * device. | |
1285 | */ | |
1286 | return ADD_TO_MLQUEUE; | |
1287 | case GOOD: | |
1288 | case COMMAND_TERMINATED: | |
1289 | case TASK_ABORTED: | |
1290 | return SUCCESS; | |
1291 | case CHECK_CONDITION: | |
1292 | rtn = scsi_check_sense(scmd); | |
1293 | if (rtn == NEEDS_RETRY) | |
1294 | goto maybe_retry; | |
1295 | /* if rtn == FAILED, we have no sense information; | |
1296 | * returning FAILED will wake the error handler thread | |
1297 | * to collect the sense and redo the decide | |
1298 | * disposition */ | |
1299 | return rtn; | |
1300 | case CONDITION_GOOD: | |
1301 | case INTERMEDIATE_GOOD: | |
1302 | case INTERMEDIATE_C_GOOD: | |
1303 | case ACA_ACTIVE: | |
1304 | /* | |
1305 | * who knows? FIXME(eric) | |
1306 | */ | |
1307 | return SUCCESS; | |
1308 | ||
1309 | case RESERVATION_CONFLICT: | |
9ccfc756 JB |
1310 | sdev_printk(KERN_INFO, scmd->device, |
1311 | "reservation conflict\n"); | |
1da177e4 LT |
1312 | return SUCCESS; /* causes immediate i/o error */ |
1313 | default: | |
1314 | return FAILED; | |
1315 | } | |
1316 | return FAILED; | |
1317 | ||
1318 | maybe_retry: | |
1319 | ||
1320 | /* we requeue for retry because the error was retryable, and | |
1321 | * the request was not marked fast fail. Note that above, | |
1322 | * even if the request is marked fast fail, we still requeue | |
1323 | * for queue congestion conditions (QUEUE_FULL or BUSY) */ | |
8884efab | 1324 | if ((++scmd->retries) <= scmd->allowed |
1da177e4 LT |
1325 | && !blk_noretry_request(scmd->request)) { |
1326 | return NEEDS_RETRY; | |
1327 | } else { | |
1328 | /* | |
1329 | * no more retries - report this one back to upper level. | |
1330 | */ | |
1331 | return SUCCESS; | |
1332 | } | |
1333 | } | |
1334 | ||
1da177e4 LT |
1335 | /** |
1336 | * scsi_eh_lock_door - Prevent medium removal for the specified device | |
1337 | * @sdev: SCSI device to prevent medium removal | |
1338 | * | |
1339 | * Locking: | |
1340 | * We must be called from process context; scsi_allocate_request() | |
1341 | * may sleep. | |
1342 | * | |
1343 | * Notes: | |
1344 | * We queue up an asynchronous "ALLOW MEDIUM REMOVAL" request on the | |
1345 | * head of the devices request queue, and continue. | |
1346 | * | |
1347 | * Bugs: | |
1348 | * scsi_allocate_request() may sleep waiting for existing requests to | |
1349 | * be processed. However, since we haven't kicked off any request | |
1350 | * processing for this host, this may deadlock. | |
1351 | * | |
1352 | * If scsi_allocate_request() fails for what ever reason, we | |
1353 | * completely forget to lock the door. | |
1354 | **/ | |
1355 | static void scsi_eh_lock_door(struct scsi_device *sdev) | |
1356 | { | |
6e68af66 | 1357 | unsigned char cmnd[MAX_COMMAND_SIZE]; |
1da177e4 | 1358 | |
6e68af66 MC |
1359 | cmnd[0] = ALLOW_MEDIUM_REMOVAL; |
1360 | cmnd[1] = 0; | |
1361 | cmnd[2] = 0; | |
1362 | cmnd[3] = 0; | |
1363 | cmnd[4] = SCSI_REMOVAL_PREVENT; | |
1364 | cmnd[5] = 0; | |
1da177e4 | 1365 | |
bb1d1073 | 1366 | scsi_execute_async(sdev, cmnd, 6, DMA_NONE, NULL, 0, 0, 10 * HZ, |
6e68af66 | 1367 | 5, NULL, NULL, GFP_KERNEL); |
1da177e4 LT |
1368 | } |
1369 | ||
1370 | ||
1371 | /** | |
1372 | * scsi_restart_operations - restart io operations to the specified host. | |
1373 | * @shost: Host we are restarting. | |
1374 | * | |
1375 | * Notes: | |
1376 | * When we entered the error handler, we blocked all further i/o to | |
1377 | * this device. we need to 'reverse' this process. | |
1378 | **/ | |
1379 | static void scsi_restart_operations(struct Scsi_Host *shost) | |
1380 | { | |
1381 | struct scsi_device *sdev; | |
939647ee | 1382 | unsigned long flags; |
1da177e4 LT |
1383 | |
1384 | /* | |
1385 | * If the door was locked, we need to insert a door lock request | |
1386 | * onto the head of the SCSI request queue for the device. There | |
1387 | * is no point trying to lock the door of an off-line device. | |
1388 | */ | |
1389 | shost_for_each_device(sdev, shost) { | |
1390 | if (scsi_device_online(sdev) && sdev->locked) | |
1391 | scsi_eh_lock_door(sdev); | |
1392 | } | |
1393 | ||
1394 | /* | |
1395 | * next free up anything directly waiting upon the host. this | |
1396 | * will be requests for character device operations, and also for | |
1397 | * ioctls to queued block devices. | |
1398 | */ | |
1399 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: waking up host to restart\n", | |
1400 | __FUNCTION__)); | |
1401 | ||
939647ee JB |
1402 | spin_lock_irqsave(shost->host_lock, flags); |
1403 | if (scsi_host_set_state(shost, SHOST_RUNNING)) | |
1404 | if (scsi_host_set_state(shost, SHOST_CANCEL)) | |
1405 | BUG_ON(scsi_host_set_state(shost, SHOST_DEL)); | |
1406 | spin_unlock_irqrestore(shost->host_lock, flags); | |
1da177e4 LT |
1407 | |
1408 | wake_up(&shost->host_wait); | |
1409 | ||
1410 | /* | |
1411 | * finally we need to re-initiate requests that may be pending. we will | |
1412 | * have had everything blocked while error handling is taking place, and | |
1413 | * now that error recovery is done, we will need to ensure that these | |
1414 | * requests are started. | |
1415 | */ | |
1416 | scsi_run_host_queues(shost); | |
1417 | } | |
1418 | ||
1419 | /** | |
1420 | * scsi_eh_ready_devs - check device ready state and recover if not. | |
1421 | * @shost: host to be recovered. | |
1422 | * @eh_done_q: list_head for processed commands. | |
1423 | * | |
1424 | **/ | |
dca84e46 DW |
1425 | void scsi_eh_ready_devs(struct Scsi_Host *shost, |
1426 | struct list_head *work_q, | |
1427 | struct list_head *done_q) | |
1da177e4 LT |
1428 | { |
1429 | if (!scsi_eh_stu(shost, work_q, done_q)) | |
1430 | if (!scsi_eh_bus_device_reset(shost, work_q, done_q)) | |
1431 | if (!scsi_eh_bus_reset(shost, work_q, done_q)) | |
1432 | if (!scsi_eh_host_reset(work_q, done_q)) | |
1433 | scsi_eh_offline_sdevs(work_q, done_q); | |
1434 | } | |
dca84e46 | 1435 | EXPORT_SYMBOL_GPL(scsi_eh_ready_devs); |
1da177e4 LT |
1436 | |
1437 | /** | |
1438 | * scsi_eh_flush_done_q - finish processed commands or retry them. | |
1439 | * @done_q: list_head of processed commands. | |
1440 | * | |
1441 | **/ | |
041c5fc3 | 1442 | void scsi_eh_flush_done_q(struct list_head *done_q) |
1da177e4 | 1443 | { |
937abeaa | 1444 | struct scsi_cmnd *scmd, *next; |
1da177e4 | 1445 | |
937abeaa CH |
1446 | list_for_each_entry_safe(scmd, next, done_q, eh_entry) { |
1447 | list_del_init(&scmd->eh_entry); | |
1da177e4 LT |
1448 | if (scsi_device_online(scmd->device) && |
1449 | !blk_noretry_request(scmd->request) && | |
8884efab | 1450 | (++scmd->retries <= scmd->allowed)) { |
1da177e4 LT |
1451 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: flush" |
1452 | " retry cmd: %p\n", | |
1453 | current->comm, | |
1454 | scmd)); | |
1455 | scsi_queue_insert(scmd, SCSI_MLQUEUE_EH_RETRY); | |
1456 | } else { | |
793698ce PM |
1457 | /* |
1458 | * If just we got sense for the device (called | |
1459 | * scsi_eh_get_sense), scmd->result is already | |
1460 | * set, do not set DRIVER_TIMEOUT. | |
1461 | */ | |
1da177e4 LT |
1462 | if (!scmd->result) |
1463 | scmd->result |= (DRIVER_TIMEOUT << 24); | |
1464 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: flush finish" | |
1465 | " cmd: %p\n", | |
1466 | current->comm, scmd)); | |
1467 | scsi_finish_command(scmd); | |
1468 | } | |
1469 | } | |
1470 | } | |
041c5fc3 | 1471 | EXPORT_SYMBOL(scsi_eh_flush_done_q); |
1da177e4 LT |
1472 | |
1473 | /** | |
1474 | * scsi_unjam_host - Attempt to fix a host which has a cmd that failed. | |
1475 | * @shost: Host to unjam. | |
1476 | * | |
1477 | * Notes: | |
1478 | * When we come in here, we *know* that all commands on the bus have | |
1479 | * either completed, failed or timed out. we also know that no further | |
1480 | * commands are being sent to the host, so things are relatively quiet | |
1481 | * and we have freedom to fiddle with things as we wish. | |
1482 | * | |
1483 | * This is only the *default* implementation. it is possible for | |
1484 | * individual drivers to supply their own version of this function, and | |
1485 | * if the maintainer wishes to do this, it is strongly suggested that | |
1486 | * this function be taken as a template and modified. this function | |
1487 | * was designed to correctly handle problems for about 95% of the | |
1488 | * different cases out there, and it should always provide at least a | |
1489 | * reasonable amount of error recovery. | |
1490 | * | |
1491 | * Any command marked 'failed' or 'timeout' must eventually have | |
1492 | * scsi_finish_cmd() called for it. we do all of the retry stuff | |
1493 | * here, so when we restart the host after we return it should have an | |
1494 | * empty queue. | |
1495 | **/ | |
1496 | static void scsi_unjam_host(struct Scsi_Host *shost) | |
1497 | { | |
1498 | unsigned long flags; | |
1499 | LIST_HEAD(eh_work_q); | |
1500 | LIST_HEAD(eh_done_q); | |
1501 | ||
1502 | spin_lock_irqsave(shost->host_lock, flags); | |
1503 | list_splice_init(&shost->eh_cmd_q, &eh_work_q); | |
1504 | spin_unlock_irqrestore(shost->host_lock, flags); | |
1505 | ||
1506 | SCSI_LOG_ERROR_RECOVERY(1, scsi_eh_prt_fail_stats(shost, &eh_work_q)); | |
1507 | ||
1508 | if (!scsi_eh_get_sense(&eh_work_q, &eh_done_q)) | |
1509 | if (!scsi_eh_abort_cmds(&eh_work_q, &eh_done_q)) | |
1510 | scsi_eh_ready_devs(shost, &eh_work_q, &eh_done_q); | |
1511 | ||
1512 | scsi_eh_flush_done_q(&eh_done_q); | |
1513 | } | |
1514 | ||
1515 | /** | |
ad42eb1b | 1516 | * scsi_error_handler - SCSI error handler thread |
1da177e4 LT |
1517 | * @data: Host for which we are running. |
1518 | * | |
1519 | * Notes: | |
ad42eb1b CH |
1520 | * This is the main error handling loop. This is run as a kernel thread |
1521 | * for every SCSI host and handles all error handling activity. | |
1da177e4 LT |
1522 | **/ |
1523 | int scsi_error_handler(void *data) | |
1524 | { | |
ad42eb1b | 1525 | struct Scsi_Host *shost = data; |
1da177e4 | 1526 | |
1da177e4 | 1527 | /* |
ad42eb1b CH |
1528 | * We use TASK_INTERRUPTIBLE so that the thread is not |
1529 | * counted against the load average as a running process. | |
1530 | * We never actually get interrupted because kthread_run | |
1531 | * disables singal delivery for the created thread. | |
1da177e4 | 1532 | */ |
3ed7a470 JB |
1533 | set_current_state(TASK_INTERRUPTIBLE); |
1534 | while (!kthread_should_stop()) { | |
ee7863bc | 1535 | if ((shost->host_failed == 0 && shost->host_eh_scheduled == 0) || |
3ed7a470 | 1536 | shost->host_failed != shost->host_busy) { |
ad42eb1b CH |
1537 | SCSI_LOG_ERROR_RECOVERY(1, |
1538 | printk("Error handler scsi_eh_%d sleeping\n", | |
1539 | shost->host_no)); | |
3ed7a470 JB |
1540 | schedule(); |
1541 | set_current_state(TASK_INTERRUPTIBLE); | |
1542 | continue; | |
1543 | } | |
1da177e4 | 1544 | |
3ed7a470 | 1545 | __set_current_state(TASK_RUNNING); |
ad42eb1b CH |
1546 | SCSI_LOG_ERROR_RECOVERY(1, |
1547 | printk("Error handler scsi_eh_%d waking up\n", | |
1548 | shost->host_no)); | |
1da177e4 | 1549 | |
1da177e4 LT |
1550 | /* |
1551 | * We have a host that is failing for some reason. Figure out | |
1552 | * what we need to do to get it up and online again (if we can). | |
1553 | * If we fail, we end up taking the thing offline. | |
1554 | */ | |
9227c33d CH |
1555 | if (shost->transportt->eh_strategy_handler) |
1556 | shost->transportt->eh_strategy_handler(shost); | |
1da177e4 LT |
1557 | else |
1558 | scsi_unjam_host(shost); | |
1559 | ||
1da177e4 LT |
1560 | /* |
1561 | * Note - if the above fails completely, the action is to take | |
1562 | * individual devices offline and flush the queue of any | |
1563 | * outstanding requests that may have been pending. When we | |
1564 | * restart, we restart any I/O to any other devices on the bus | |
1565 | * which are still online. | |
1566 | */ | |
1567 | scsi_restart_operations(shost); | |
3ed7a470 | 1568 | set_current_state(TASK_INTERRUPTIBLE); |
1da177e4 | 1569 | } |
461a0ffb SR |
1570 | __set_current_state(TASK_RUNNING); |
1571 | ||
ad42eb1b CH |
1572 | SCSI_LOG_ERROR_RECOVERY(1, |
1573 | printk("Error handler scsi_eh_%d exiting\n", shost->host_no)); | |
3ed7a470 | 1574 | shost->ehandler = NULL; |
1da177e4 LT |
1575 | return 0; |
1576 | } | |
1577 | ||
1578 | /* | |
1579 | * Function: scsi_report_bus_reset() | |
1580 | * | |
1581 | * Purpose: Utility function used by low-level drivers to report that | |
1582 | * they have observed a bus reset on the bus being handled. | |
1583 | * | |
1584 | * Arguments: shost - Host in question | |
1585 | * channel - channel on which reset was observed. | |
1586 | * | |
1587 | * Returns: Nothing | |
1588 | * | |
1589 | * Lock status: Host lock must be held. | |
1590 | * | |
1591 | * Notes: This only needs to be called if the reset is one which | |
1592 | * originates from an unknown location. Resets originated | |
1593 | * by the mid-level itself don't need to call this, but there | |
1594 | * should be no harm. | |
1595 | * | |
1596 | * The main purpose of this is to make sure that a CHECK_CONDITION | |
1597 | * is properly treated. | |
1598 | */ | |
1599 | void scsi_report_bus_reset(struct Scsi_Host *shost, int channel) | |
1600 | { | |
1601 | struct scsi_device *sdev; | |
1602 | ||
1603 | __shost_for_each_device(sdev, shost) { | |
422c0d61 | 1604 | if (channel == sdev_channel(sdev)) { |
1da177e4 LT |
1605 | sdev->was_reset = 1; |
1606 | sdev->expecting_cc_ua = 1; | |
1607 | } | |
1608 | } | |
1609 | } | |
1610 | EXPORT_SYMBOL(scsi_report_bus_reset); | |
1611 | ||
1612 | /* | |
1613 | * Function: scsi_report_device_reset() | |
1614 | * | |
1615 | * Purpose: Utility function used by low-level drivers to report that | |
1616 | * they have observed a device reset on the device being handled. | |
1617 | * | |
1618 | * Arguments: shost - Host in question | |
1619 | * channel - channel on which reset was observed | |
1620 | * target - target on which reset was observed | |
1621 | * | |
1622 | * Returns: Nothing | |
1623 | * | |
1624 | * Lock status: Host lock must be held | |
1625 | * | |
1626 | * Notes: This only needs to be called if the reset is one which | |
1627 | * originates from an unknown location. Resets originated | |
1628 | * by the mid-level itself don't need to call this, but there | |
1629 | * should be no harm. | |
1630 | * | |
1631 | * The main purpose of this is to make sure that a CHECK_CONDITION | |
1632 | * is properly treated. | |
1633 | */ | |
1634 | void scsi_report_device_reset(struct Scsi_Host *shost, int channel, int target) | |
1635 | { | |
1636 | struct scsi_device *sdev; | |
1637 | ||
1638 | __shost_for_each_device(sdev, shost) { | |
422c0d61 JG |
1639 | if (channel == sdev_channel(sdev) && |
1640 | target == sdev_id(sdev)) { | |
1da177e4 LT |
1641 | sdev->was_reset = 1; |
1642 | sdev->expecting_cc_ua = 1; | |
1643 | } | |
1644 | } | |
1645 | } | |
1646 | EXPORT_SYMBOL(scsi_report_device_reset); | |
1647 | ||
1648 | static void | |
1649 | scsi_reset_provider_done_command(struct scsi_cmnd *scmd) | |
1650 | { | |
1651 | } | |
1652 | ||
1653 | /* | |
1654 | * Function: scsi_reset_provider | |
1655 | * | |
1656 | * Purpose: Send requested reset to a bus or device at any phase. | |
1657 | * | |
1658 | * Arguments: device - device to send reset to | |
1659 | * flag - reset type (see scsi.h) | |
1660 | * | |
1661 | * Returns: SUCCESS/FAILURE. | |
1662 | * | |
1663 | * Notes: This is used by the SCSI Generic driver to provide | |
1664 | * Bus/Device reset capability. | |
1665 | */ | |
1666 | int | |
1667 | scsi_reset_provider(struct scsi_device *dev, int flag) | |
1668 | { | |
1669 | struct scsi_cmnd *scmd = scsi_get_command(dev, GFP_KERNEL); | |
d7a1bb0a | 1670 | struct Scsi_Host *shost = dev->host; |
1da177e4 | 1671 | struct request req; |
d7a1bb0a | 1672 | unsigned long flags; |
1da177e4 LT |
1673 | int rtn; |
1674 | ||
1675 | scmd->request = &req; | |
1676 | memset(&scmd->eh_timeout, 0, sizeof(scmd->eh_timeout)); | |
b4edcbca | 1677 | |
1da177e4 LT |
1678 | memset(&scmd->cmnd, '\0', sizeof(scmd->cmnd)); |
1679 | ||
1680 | scmd->scsi_done = scsi_reset_provider_done_command; | |
1da177e4 LT |
1681 | scmd->request_buffer = NULL; |
1682 | scmd->request_bufflen = 0; | |
1da177e4 LT |
1683 | |
1684 | scmd->cmd_len = 0; | |
1685 | ||
1686 | scmd->sc_data_direction = DMA_BIDIRECTIONAL; | |
1da177e4 LT |
1687 | |
1688 | init_timer(&scmd->eh_timeout); | |
1689 | ||
d7a1bb0a JS |
1690 | spin_lock_irqsave(shost->host_lock, flags); |
1691 | shost->tmf_in_progress = 1; | |
1692 | spin_unlock_irqrestore(shost->host_lock, flags); | |
1693 | ||
1da177e4 LT |
1694 | switch (flag) { |
1695 | case SCSI_TRY_RESET_DEVICE: | |
1696 | rtn = scsi_try_bus_device_reset(scmd); | |
1697 | if (rtn == SUCCESS) | |
1698 | break; | |
1699 | /* FALLTHROUGH */ | |
1700 | case SCSI_TRY_RESET_BUS: | |
1701 | rtn = scsi_try_bus_reset(scmd); | |
1702 | if (rtn == SUCCESS) | |
1703 | break; | |
1704 | /* FALLTHROUGH */ | |
1705 | case SCSI_TRY_RESET_HOST: | |
1706 | rtn = scsi_try_host_reset(scmd); | |
1707 | break; | |
1708 | default: | |
1709 | rtn = FAILED; | |
1710 | } | |
1711 | ||
d7a1bb0a JS |
1712 | spin_lock_irqsave(shost->host_lock, flags); |
1713 | shost->tmf_in_progress = 0; | |
1714 | spin_unlock_irqrestore(shost->host_lock, flags); | |
1715 | ||
1716 | /* | |
1717 | * be sure to wake up anyone who was sleeping or had their queue | |
1718 | * suspended while we performed the TMF. | |
1719 | */ | |
1720 | SCSI_LOG_ERROR_RECOVERY(3, | |
1721 | printk("%s: waking up host to restart after TMF\n", | |
1722 | __FUNCTION__)); | |
1723 | ||
1724 | wake_up(&shost->host_wait); | |
1725 | ||
1726 | scsi_run_host_queues(shost); | |
1727 | ||
1da177e4 LT |
1728 | scsi_next_command(scmd); |
1729 | return rtn; | |
1730 | } | |
1731 | EXPORT_SYMBOL(scsi_reset_provider); | |
1732 | ||
1733 | /** | |
1734 | * scsi_normalize_sense - normalize main elements from either fixed or | |
1735 | * descriptor sense data format into a common format. | |
1736 | * | |
1737 | * @sense_buffer: byte array containing sense data returned by device | |
1738 | * @sb_len: number of valid bytes in sense_buffer | |
1739 | * @sshdr: pointer to instance of structure that common | |
1740 | * elements are written to. | |
1741 | * | |
1742 | * Notes: | |
1743 | * The "main elements" from sense data are: response_code, sense_key, | |
1744 | * asc, ascq and additional_length (only for descriptor format). | |
1745 | * | |
1746 | * Typically this function can be called after a device has | |
1747 | * responded to a SCSI command with the CHECK_CONDITION status. | |
1748 | * | |
1749 | * Return value: | |
1750 | * 1 if valid sense data information found, else 0; | |
1751 | **/ | |
1752 | int scsi_normalize_sense(const u8 *sense_buffer, int sb_len, | |
1753 | struct scsi_sense_hdr *sshdr) | |
1754 | { | |
33aa687d | 1755 | if (!sense_buffer || !sb_len) |
1da177e4 LT |
1756 | return 0; |
1757 | ||
1758 | memset(sshdr, 0, sizeof(struct scsi_sense_hdr)); | |
1759 | ||
1760 | sshdr->response_code = (sense_buffer[0] & 0x7f); | |
33aa687d JB |
1761 | |
1762 | if (!scsi_sense_valid(sshdr)) | |
1763 | return 0; | |
1764 | ||
1da177e4 LT |
1765 | if (sshdr->response_code >= 0x72) { |
1766 | /* | |
1767 | * descriptor format | |
1768 | */ | |
1769 | if (sb_len > 1) | |
1770 | sshdr->sense_key = (sense_buffer[1] & 0xf); | |
1771 | if (sb_len > 2) | |
1772 | sshdr->asc = sense_buffer[2]; | |
1773 | if (sb_len > 3) | |
1774 | sshdr->ascq = sense_buffer[3]; | |
1775 | if (sb_len > 7) | |
1776 | sshdr->additional_length = sense_buffer[7]; | |
1777 | } else { | |
1778 | /* | |
1779 | * fixed format | |
1780 | */ | |
1781 | if (sb_len > 2) | |
1782 | sshdr->sense_key = (sense_buffer[2] & 0xf); | |
1783 | if (sb_len > 7) { | |
1784 | sb_len = (sb_len < (sense_buffer[7] + 8)) ? | |
1785 | sb_len : (sense_buffer[7] + 8); | |
1786 | if (sb_len > 12) | |
1787 | sshdr->asc = sense_buffer[12]; | |
1788 | if (sb_len > 13) | |
1789 | sshdr->ascq = sense_buffer[13]; | |
1790 | } | |
1791 | } | |
1792 | ||
1793 | return 1; | |
1794 | } | |
1795 | EXPORT_SYMBOL(scsi_normalize_sense); | |
1796 | ||
1da177e4 LT |
1797 | int scsi_command_normalize_sense(struct scsi_cmnd *cmd, |
1798 | struct scsi_sense_hdr *sshdr) | |
1799 | { | |
1800 | return scsi_normalize_sense(cmd->sense_buffer, | |
1801 | sizeof(cmd->sense_buffer), sshdr); | |
1802 | } | |
1803 | EXPORT_SYMBOL(scsi_command_normalize_sense); | |
1804 | ||
1805 | /** | |
1806 | * scsi_sense_desc_find - search for a given descriptor type in | |
1807 | * descriptor sense data format. | |
1808 | * | |
1809 | * @sense_buffer: byte array of descriptor format sense data | |
1810 | * @sb_len: number of valid bytes in sense_buffer | |
1811 | * @desc_type: value of descriptor type to find | |
1812 | * (e.g. 0 -> information) | |
1813 | * | |
1814 | * Notes: | |
1815 | * only valid when sense data is in descriptor format | |
1816 | * | |
1817 | * Return value: | |
1818 | * pointer to start of (first) descriptor if found else NULL | |
1819 | **/ | |
1820 | const u8 * scsi_sense_desc_find(const u8 * sense_buffer, int sb_len, | |
1821 | int desc_type) | |
1822 | { | |
1823 | int add_sen_len, add_len, desc_len, k; | |
1824 | const u8 * descp; | |
1825 | ||
1826 | if ((sb_len < 8) || (0 == (add_sen_len = sense_buffer[7]))) | |
1827 | return NULL; | |
1828 | if ((sense_buffer[0] < 0x72) || (sense_buffer[0] > 0x73)) | |
1829 | return NULL; | |
1830 | add_sen_len = (add_sen_len < (sb_len - 8)) ? | |
1831 | add_sen_len : (sb_len - 8); | |
1832 | descp = &sense_buffer[8]; | |
1833 | for (desc_len = 0, k = 0; k < add_sen_len; k += desc_len) { | |
1834 | descp += desc_len; | |
1835 | add_len = (k < (add_sen_len - 1)) ? descp[1]: -1; | |
1836 | desc_len = add_len + 2; | |
1837 | if (descp[0] == desc_type) | |
1838 | return descp; | |
1839 | if (add_len < 0) // short descriptor ?? | |
1840 | break; | |
1841 | } | |
1842 | return NULL; | |
1843 | } | |
1844 | EXPORT_SYMBOL(scsi_sense_desc_find); | |
1845 | ||
1846 | /** | |
1847 | * scsi_get_sense_info_fld - attempts to get information field from | |
1848 | * sense data (either fixed or descriptor format) | |
1849 | * | |
1850 | * @sense_buffer: byte array of sense data | |
1851 | * @sb_len: number of valid bytes in sense_buffer | |
1852 | * @info_out: pointer to 64 integer where 8 or 4 byte information | |
1853 | * field will be placed if found. | |
1854 | * | |
1855 | * Return value: | |
1856 | * 1 if information field found, 0 if not found. | |
1857 | **/ | |
1858 | int scsi_get_sense_info_fld(const u8 * sense_buffer, int sb_len, | |
1859 | u64 * info_out) | |
1860 | { | |
1861 | int j; | |
1862 | const u8 * ucp; | |
1863 | u64 ull; | |
1864 | ||
1865 | if (sb_len < 7) | |
1866 | return 0; | |
1867 | switch (sense_buffer[0] & 0x7f) { | |
1868 | case 0x70: | |
1869 | case 0x71: | |
1870 | if (sense_buffer[0] & 0x80) { | |
1871 | *info_out = (sense_buffer[3] << 24) + | |
1872 | (sense_buffer[4] << 16) + | |
1873 | (sense_buffer[5] << 8) + sense_buffer[6]; | |
1874 | return 1; | |
1875 | } else | |
1876 | return 0; | |
1877 | case 0x72: | |
1878 | case 0x73: | |
1879 | ucp = scsi_sense_desc_find(sense_buffer, sb_len, | |
1880 | 0 /* info desc */); | |
1881 | if (ucp && (0xa == ucp[1])) { | |
1882 | ull = 0; | |
1883 | for (j = 0; j < 8; ++j) { | |
1884 | if (j > 0) | |
1885 | ull <<= 8; | |
1886 | ull |= ucp[4 + j]; | |
1887 | } | |
1888 | *info_out = ull; | |
1889 | return 1; | |
1890 | } else | |
1891 | return 0; | |
1892 | default: | |
1893 | return 0; | |
1894 | } | |
1895 | } | |
1896 | EXPORT_SYMBOL(scsi_get_sense_info_fld); |