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1da177e4 LT |
1 | /* |
2 | * scsi_error.c Copyright (C) 1997 Eric Youngdale | |
3 | * | |
4 | * SCSI error/timeout handling | |
5 | * Initial versions: Eric Youngdale. Based upon conversations with | |
6 | * Leonard Zubkoff and David Miller at Linux Expo, | |
7 | * ideas originating from all over the place. | |
8 | * | |
9 | * Restructured scsi_unjam_host and associated functions. | |
10 | * September 04, 2002 Mike Anderson (andmike@us.ibm.com) | |
11 | * | |
12 | * Forward port of Russell King's (rmk@arm.linux.org.uk) changes and | |
13 | * minor cleanups. | |
14 | * September 30, 2002 Mike Anderson (andmike@us.ibm.com) | |
15 | */ | |
16 | ||
17 | #include <linux/module.h> | |
18 | #include <linux/sched.h> | |
19 | #include <linux/timer.h> | |
20 | #include <linux/string.h> | |
21 | #include <linux/slab.h> | |
22 | #include <linux/kernel.h> | |
c5478def | 23 | #include <linux/kthread.h> |
1da177e4 LT |
24 | #include <linux/interrupt.h> |
25 | #include <linux/blkdev.h> | |
26 | #include <linux/delay.h> | |
27 | ||
28 | #include <scsi/scsi.h> | |
beb40487 | 29 | #include <scsi/scsi_cmnd.h> |
1da177e4 LT |
30 | #include <scsi/scsi_dbg.h> |
31 | #include <scsi/scsi_device.h> | |
32 | #include <scsi/scsi_eh.h> | |
c829c394 | 33 | #include <scsi/scsi_transport.h> |
1da177e4 LT |
34 | #include <scsi/scsi_host.h> |
35 | #include <scsi/scsi_ioctl.h> | |
1da177e4 LT |
36 | |
37 | #include "scsi_priv.h" | |
38 | #include "scsi_logging.h" | |
39 | ||
40 | #define SENSE_TIMEOUT (10*HZ) | |
41 | #define START_UNIT_TIMEOUT (30*HZ) | |
42 | ||
43 | /* | |
44 | * These should *probably* be handled by the host itself. | |
45 | * Since it is allowed to sleep, it probably should. | |
46 | */ | |
47 | #define BUS_RESET_SETTLE_TIME (10) | |
48 | #define HOST_RESET_SETTLE_TIME (10) | |
49 | ||
50 | /* called with shost->host_lock held */ | |
51 | void scsi_eh_wakeup(struct Scsi_Host *shost) | |
52 | { | |
53 | if (shost->host_busy == shost->host_failed) { | |
3ed7a470 | 54 | wake_up_process(shost->ehandler); |
1da177e4 LT |
55 | SCSI_LOG_ERROR_RECOVERY(5, |
56 | printk("Waking error handler thread\n")); | |
57 | } | |
58 | } | |
f8bbfc24 TH |
59 | |
60 | /** | |
61 | * scsi_schedule_eh - schedule EH for SCSI host | |
62 | * @shost: SCSI host to invoke error handling on. | |
63 | * | |
64 | * Schedule SCSI EH without scmd. | |
65 | **/ | |
66 | void scsi_schedule_eh(struct Scsi_Host *shost) | |
67 | { | |
68 | unsigned long flags; | |
69 | ||
70 | spin_lock_irqsave(shost->host_lock, flags); | |
71 | ||
72 | if (scsi_host_set_state(shost, SHOST_RECOVERY) == 0 || | |
73 | scsi_host_set_state(shost, SHOST_CANCEL_RECOVERY) == 0) { | |
74 | shost->host_eh_scheduled++; | |
75 | scsi_eh_wakeup(shost); | |
76 | } | |
77 | ||
78 | spin_unlock_irqrestore(shost->host_lock, flags); | |
79 | } | |
80 | EXPORT_SYMBOL_GPL(scsi_schedule_eh); | |
1da177e4 LT |
81 | |
82 | /** | |
83 | * scsi_eh_scmd_add - add scsi cmd to error handling. | |
84 | * @scmd: scmd to run eh on. | |
85 | * @eh_flag: optional SCSI_EH flag. | |
86 | * | |
87 | * Return value: | |
88 | * 0 on failure. | |
89 | **/ | |
90 | int scsi_eh_scmd_add(struct scsi_cmnd *scmd, int eh_flag) | |
91 | { | |
92 | struct Scsi_Host *shost = scmd->device->host; | |
93 | unsigned long flags; | |
939647ee | 94 | int ret = 0; |
1da177e4 | 95 | |
3ed7a470 | 96 | if (!shost->ehandler) |
1da177e4 LT |
97 | return 0; |
98 | ||
99 | spin_lock_irqsave(shost->host_lock, flags); | |
939647ee JB |
100 | if (scsi_host_set_state(shost, SHOST_RECOVERY)) |
101 | if (scsi_host_set_state(shost, SHOST_CANCEL_RECOVERY)) | |
102 | goto out_unlock; | |
1da177e4 | 103 | |
939647ee | 104 | ret = 1; |
3111b0d1 | 105 | scmd->eh_eflags |= eh_flag; |
1da177e4 | 106 | list_add_tail(&scmd->eh_entry, &shost->eh_cmd_q); |
1da177e4 LT |
107 | shost->host_failed++; |
108 | scsi_eh_wakeup(shost); | |
939647ee | 109 | out_unlock: |
1da177e4 | 110 | spin_unlock_irqrestore(shost->host_lock, flags); |
939647ee | 111 | return ret; |
1da177e4 LT |
112 | } |
113 | ||
114 | /** | |
115 | * scsi_add_timer - Start timeout timer for a single scsi command. | |
116 | * @scmd: scsi command that is about to start running. | |
117 | * @timeout: amount of time to allow this command to run. | |
118 | * @complete: timeout function to call if timer isn't canceled. | |
119 | * | |
120 | * Notes: | |
121 | * This should be turned into an inline function. Each scsi command | |
122 | * has its own timer, and as it is added to the queue, we set up the | |
123 | * timer. When the command completes, we cancel the timer. | |
124 | **/ | |
125 | void scsi_add_timer(struct scsi_cmnd *scmd, int timeout, | |
126 | void (*complete)(struct scsi_cmnd *)) | |
127 | { | |
128 | ||
129 | /* | |
130 | * If the clock was already running for this command, then | |
131 | * first delete the timer. The timer handling code gets rather | |
132 | * confused if we don't do this. | |
133 | */ | |
134 | if (scmd->eh_timeout.function) | |
135 | del_timer(&scmd->eh_timeout); | |
136 | ||
137 | scmd->eh_timeout.data = (unsigned long)scmd; | |
138 | scmd->eh_timeout.expires = jiffies + timeout; | |
139 | scmd->eh_timeout.function = (void (*)(unsigned long)) complete; | |
140 | ||
141 | SCSI_LOG_ERROR_RECOVERY(5, printk("%s: scmd: %p, time:" | |
142 | " %d, (%p)\n", __FUNCTION__, | |
143 | scmd, timeout, complete)); | |
144 | ||
145 | add_timer(&scmd->eh_timeout); | |
146 | } | |
1da177e4 LT |
147 | |
148 | /** | |
149 | * scsi_delete_timer - Delete/cancel timer for a given function. | |
150 | * @scmd: Cmd that we are canceling timer for | |
151 | * | |
152 | * Notes: | |
153 | * This should be turned into an inline function. | |
154 | * | |
155 | * Return value: | |
156 | * 1 if we were able to detach the timer. 0 if we blew it, and the | |
157 | * timer function has already started to run. | |
158 | **/ | |
159 | int scsi_delete_timer(struct scsi_cmnd *scmd) | |
160 | { | |
161 | int rtn; | |
162 | ||
163 | rtn = del_timer(&scmd->eh_timeout); | |
164 | ||
165 | SCSI_LOG_ERROR_RECOVERY(5, printk("%s: scmd: %p," | |
166 | " rtn: %d\n", __FUNCTION__, | |
167 | scmd, rtn)); | |
168 | ||
169 | scmd->eh_timeout.data = (unsigned long)NULL; | |
170 | scmd->eh_timeout.function = NULL; | |
171 | ||
172 | return rtn; | |
173 | } | |
1da177e4 LT |
174 | |
175 | /** | |
176 | * scsi_times_out - Timeout function for normal scsi commands. | |
177 | * @scmd: Cmd that is timing out. | |
178 | * | |
179 | * Notes: | |
180 | * We do not need to lock this. There is the potential for a race | |
181 | * only in that the normal completion handling might run, but if the | |
182 | * normal completion function determines that the timer has already | |
183 | * fired, then it mustn't do anything. | |
184 | **/ | |
185 | void scsi_times_out(struct scsi_cmnd *scmd) | |
186 | { | |
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. | |
227 | **/ | |
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. | |
248 | **/ | |
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. | |
298 | **/ | |
299 | static int scsi_check_sense(struct scsi_cmnd *scmd) | |
300 | { | |
301 | struct scsi_sense_hdr sshdr; | |
302 | ||
303 | if (! scsi_command_normalize_sense(scmd, &sshdr)) | |
304 | return FAILED; /* no valid sense data */ | |
305 | ||
306 | if (scsi_sense_is_deferred(&sshdr)) | |
307 | return NEEDS_RETRY; | |
308 | ||
309 | /* | |
310 | * Previous logic looked for FILEMARK, EOM or ILI which are | |
311 | * mainly associated with tapes and returned SUCCESS. | |
312 | */ | |
313 | if (sshdr.response_code == 0x70) { | |
314 | /* fixed format */ | |
315 | if (scmd->sense_buffer[2] & 0xe0) | |
316 | return SUCCESS; | |
317 | } else { | |
318 | /* | |
319 | * descriptor format: look for "stream commands sense data | |
320 | * descriptor" (see SSC-3). Assume single sense data | |
321 | * descriptor. Ignore ILI from SBC-2 READ LONG and WRITE LONG. | |
322 | */ | |
323 | if ((sshdr.additional_length > 3) && | |
324 | (scmd->sense_buffer[8] == 0x4) && | |
325 | (scmd->sense_buffer[11] & 0xe0)) | |
326 | return SUCCESS; | |
327 | } | |
328 | ||
329 | switch (sshdr.sense_key) { | |
330 | case NO_SENSE: | |
331 | return SUCCESS; | |
332 | case RECOVERED_ERROR: | |
333 | return /* soft_error */ SUCCESS; | |
334 | ||
335 | case ABORTED_COMMAND: | |
336 | return NEEDS_RETRY; | |
337 | case NOT_READY: | |
338 | case UNIT_ATTENTION: | |
339 | /* | |
340 | * if we are expecting a cc/ua because of a bus reset that we | |
341 | * performed, treat this just as a retry. otherwise this is | |
342 | * information that we should pass up to the upper-level driver | |
343 | * so that we can deal with it there. | |
344 | */ | |
345 | if (scmd->device->expecting_cc_ua) { | |
346 | scmd->device->expecting_cc_ua = 0; | |
347 | return NEEDS_RETRY; | |
348 | } | |
349 | /* | |
350 | * if the device is in the process of becoming ready, we | |
351 | * should retry. | |
352 | */ | |
353 | if ((sshdr.asc == 0x04) && (sshdr.ascq == 0x01)) | |
354 | return NEEDS_RETRY; | |
355 | /* | |
356 | * if the device is not started, we need to wake | |
357 | * the error handler to start the motor | |
358 | */ | |
359 | if (scmd->device->allow_restart && | |
360 | (sshdr.asc == 0x04) && (sshdr.ascq == 0x02)) | |
361 | return FAILED; | |
362 | return SUCCESS; | |
363 | ||
364 | /* these three are not supported */ | |
365 | case COPY_ABORTED: | |
366 | case VOLUME_OVERFLOW: | |
367 | case MISCOMPARE: | |
368 | return SUCCESS; | |
369 | ||
370 | case MEDIUM_ERROR: | |
fd1b494d LT |
371 | if (sshdr.asc == 0x11 || /* UNRECOVERED READ ERR */ |
372 | sshdr.asc == 0x13 || /* AMNF DATA FIELD */ | |
373 | sshdr.asc == 0x14) { /* RECORD NOT FOUND */ | |
374 | return SUCCESS; | |
375 | } | |
1da177e4 LT |
376 | return NEEDS_RETRY; |
377 | ||
378 | case HARDWARE_ERROR: | |
379 | if (scmd->device->retry_hwerror) | |
380 | return NEEDS_RETRY; | |
381 | else | |
382 | return SUCCESS; | |
383 | ||
384 | case ILLEGAL_REQUEST: | |
385 | case BLANK_CHECK: | |
386 | case DATA_PROTECT: | |
387 | default: | |
388 | return SUCCESS; | |
389 | } | |
390 | } | |
391 | ||
392 | /** | |
393 | * scsi_eh_completed_normally - Disposition a eh cmd on return from LLD. | |
394 | * @scmd: SCSI cmd to examine. | |
395 | * | |
396 | * Notes: | |
397 | * This is *only* called when we are examining the status of commands | |
398 | * queued during error recovery. the main difference here is that we | |
399 | * don't allow for the possibility of retries here, and we are a lot | |
400 | * more restrictive about what we consider acceptable. | |
401 | **/ | |
402 | static int scsi_eh_completed_normally(struct scsi_cmnd *scmd) | |
403 | { | |
404 | /* | |
405 | * first check the host byte, to see if there is anything in there | |
406 | * that would indicate what we need to do. | |
407 | */ | |
408 | if (host_byte(scmd->result) == DID_RESET) { | |
409 | /* | |
410 | * rats. we are already in the error handler, so we now | |
411 | * get to try and figure out what to do next. if the sense | |
412 | * is valid, we have a pretty good idea of what to do. | |
413 | * if not, we mark it as FAILED. | |
414 | */ | |
415 | return scsi_check_sense(scmd); | |
416 | } | |
417 | if (host_byte(scmd->result) != DID_OK) | |
418 | return FAILED; | |
419 | ||
420 | /* | |
421 | * next, check the message byte. | |
422 | */ | |
423 | if (msg_byte(scmd->result) != COMMAND_COMPLETE) | |
424 | return FAILED; | |
425 | ||
426 | /* | |
427 | * now, check the status byte to see if this indicates | |
428 | * anything special. | |
429 | */ | |
430 | switch (status_byte(scmd->result)) { | |
431 | case GOOD: | |
432 | case COMMAND_TERMINATED: | |
433 | return SUCCESS; | |
434 | case CHECK_CONDITION: | |
435 | return scsi_check_sense(scmd); | |
436 | case CONDITION_GOOD: | |
437 | case INTERMEDIATE_GOOD: | |
438 | case INTERMEDIATE_C_GOOD: | |
439 | /* | |
440 | * who knows? FIXME(eric) | |
441 | */ | |
442 | return SUCCESS; | |
443 | case BUSY: | |
444 | case QUEUE_FULL: | |
445 | case RESERVATION_CONFLICT: | |
446 | default: | |
447 | return FAILED; | |
448 | } | |
449 | return FAILED; | |
450 | } | |
451 | ||
1da177e4 LT |
452 | /** |
453 | * scsi_eh_done - Completion function for error handling. | |
454 | * @scmd: Cmd that is done. | |
455 | **/ | |
456 | static void scsi_eh_done(struct scsi_cmnd *scmd) | |
457 | { | |
85631672 MR |
458 | struct completion *eh_action; |
459 | ||
7dfdc9a5 CH |
460 | SCSI_LOG_ERROR_RECOVERY(3, |
461 | printk("%s scmd: %p result: %x\n", | |
462 | __FUNCTION__, scmd, scmd->result)); | |
85631672 MR |
463 | |
464 | eh_action = scmd->device->host->eh_action; | |
465 | if (eh_action) | |
466 | complete(eh_action); | |
1da177e4 LT |
467 | } |
468 | ||
292148f8 BK |
469 | /** |
470 | * scsi_try_host_reset - ask host adapter to reset itself | |
471 | * @scmd: SCSI cmd to send hsot reset. | |
472 | **/ | |
473 | static int scsi_try_host_reset(struct scsi_cmnd *scmd) | |
474 | { | |
475 | unsigned long flags; | |
476 | int rtn; | |
477 | ||
478 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Snd Host RST\n", | |
479 | __FUNCTION__)); | |
480 | ||
481 | if (!scmd->device->host->hostt->eh_host_reset_handler) | |
482 | return FAILED; | |
483 | ||
484 | rtn = scmd->device->host->hostt->eh_host_reset_handler(scmd); | |
485 | ||
486 | if (rtn == SUCCESS) { | |
487 | if (!scmd->device->host->hostt->skip_settle_delay) | |
488 | ssleep(HOST_RESET_SETTLE_TIME); | |
489 | spin_lock_irqsave(scmd->device->host->host_lock, flags); | |
490 | scsi_report_bus_reset(scmd->device->host, | |
491 | scmd_channel(scmd)); | |
492 | spin_unlock_irqrestore(scmd->device->host->host_lock, flags); | |
493 | } | |
494 | ||
495 | return rtn; | |
496 | } | |
497 | ||
498 | /** | |
499 | * scsi_try_bus_reset - ask host to perform a bus reset | |
500 | * @scmd: SCSI cmd to send bus reset. | |
501 | **/ | |
502 | static int scsi_try_bus_reset(struct scsi_cmnd *scmd) | |
503 | { | |
504 | unsigned long flags; | |
505 | int rtn; | |
506 | ||
507 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Snd Bus RST\n", | |
508 | __FUNCTION__)); | |
509 | ||
510 | if (!scmd->device->host->hostt->eh_bus_reset_handler) | |
511 | return FAILED; | |
512 | ||
513 | rtn = scmd->device->host->hostt->eh_bus_reset_handler(scmd); | |
514 | ||
515 | if (rtn == SUCCESS) { | |
516 | if (!scmd->device->host->hostt->skip_settle_delay) | |
517 | ssleep(BUS_RESET_SETTLE_TIME); | |
518 | spin_lock_irqsave(scmd->device->host->host_lock, flags); | |
519 | scsi_report_bus_reset(scmd->device->host, | |
520 | scmd_channel(scmd)); | |
521 | spin_unlock_irqrestore(scmd->device->host->host_lock, flags); | |
522 | } | |
523 | ||
524 | return rtn; | |
525 | } | |
526 | ||
527 | /** | |
528 | * scsi_try_bus_device_reset - Ask host to perform a BDR on a dev | |
529 | * @scmd: SCSI cmd used to send BDR | |
530 | * | |
531 | * Notes: | |
532 | * There is no timeout for this operation. if this operation is | |
533 | * unreliable for a given host, then the host itself needs to put a | |
534 | * timer on it, and set the host back to a consistent state prior to | |
535 | * returning. | |
536 | **/ | |
537 | static int scsi_try_bus_device_reset(struct scsi_cmnd *scmd) | |
538 | { | |
539 | int rtn; | |
540 | ||
541 | if (!scmd->device->host->hostt->eh_device_reset_handler) | |
542 | return FAILED; | |
543 | ||
544 | rtn = scmd->device->host->hostt->eh_device_reset_handler(scmd); | |
545 | if (rtn == SUCCESS) { | |
546 | scmd->device->was_reset = 1; | |
547 | scmd->device->expecting_cc_ua = 1; | |
548 | } | |
549 | ||
550 | return rtn; | |
551 | } | |
552 | ||
553 | static int __scsi_try_to_abort_cmd(struct scsi_cmnd *scmd) | |
554 | { | |
555 | if (!scmd->device->host->hostt->eh_abort_handler) | |
556 | return FAILED; | |
557 | ||
558 | return scmd->device->host->hostt->eh_abort_handler(scmd); | |
559 | } | |
560 | ||
561 | /** | |
562 | * scsi_try_to_abort_cmd - Ask host to abort a running command. | |
563 | * @scmd: SCSI cmd to abort from Lower Level. | |
564 | * | |
565 | * Notes: | |
566 | * This function will not return until the user's completion function | |
567 | * has been called. there is no timeout on this operation. if the | |
568 | * author of the low-level driver wishes this operation to be timed, | |
569 | * they can provide this facility themselves. helper functions in | |
570 | * scsi_error.c can be supplied to make this easier to do. | |
571 | **/ | |
572 | static int scsi_try_to_abort_cmd(struct scsi_cmnd *scmd) | |
573 | { | |
574 | /* | |
575 | * scsi_done was called just after the command timed out and before | |
576 | * we had a chance to process it. (db) | |
577 | */ | |
578 | if (scmd->serial_number == 0) | |
579 | return SUCCESS; | |
580 | return __scsi_try_to_abort_cmd(scmd); | |
581 | } | |
582 | ||
583 | static void scsi_abort_eh_cmnd(struct scsi_cmnd *scmd) | |
584 | { | |
585 | if (__scsi_try_to_abort_cmd(scmd) != SUCCESS) | |
586 | if (scsi_try_bus_device_reset(scmd) != SUCCESS) | |
587 | if (scsi_try_bus_reset(scmd) != SUCCESS) | |
588 | scsi_try_host_reset(scmd); | |
589 | } | |
590 | ||
1da177e4 | 591 | /** |
2dc611de CH |
592 | * scsi_send_eh_cmnd - submit a scsi command as part of error recory |
593 | * @scmd: SCSI command structure to hijack | |
594 | * @cmnd: CDB to send | |
595 | * @cmnd_size: size in bytes of @cmnd | |
596 | * @timeout: timeout for this request | |
597 | * @copy_sense: request sense data if set to 1 | |
598 | * | |
599 | * This function is used to send a scsi command down to a target device | |
600 | * as part of the error recovery process. If @copy_sense is 0 the command | |
601 | * sent must be one that does not transfer any data. If @copy_sense is 1 | |
602 | * the command must be REQUEST_SENSE and this functions copies out the | |
603 | * sense buffer it got into @scmd->sense_buffer. | |
1da177e4 | 604 | * |
1da177e4 LT |
605 | * Return value: |
606 | * SUCCESS or FAILED or NEEDS_RETRY | |
607 | **/ | |
0db99e33 MC |
608 | static int scsi_send_eh_cmnd(struct scsi_cmnd *scmd, unsigned char *cmnd, |
609 | int cmnd_size, int timeout, int copy_sense) | |
1da177e4 | 610 | { |
f59114b7 | 611 | struct scsi_device *sdev = scmd->device; |
612 | struct Scsi_Host *shost = sdev->host; | |
631c228c | 613 | int old_result = scmd->result; |
7fbb3645 | 614 | DECLARE_COMPLETION_ONSTACK(done); |
7dfdc9a5 | 615 | unsigned long timeleft; |
1da177e4 | 616 | unsigned long flags; |
2dc611de | 617 | struct scatterlist sgl; |
631c228c CH |
618 | unsigned char old_cmnd[MAX_COMMAND_SIZE]; |
619 | enum dma_data_direction old_data_direction; | |
620 | unsigned short old_use_sg; | |
621 | unsigned char old_cmd_len; | |
622 | unsigned old_bufflen; | |
623 | void *old_buffer; | |
7dfdc9a5 | 624 | int rtn; |
1da177e4 | 625 | |
631c228c CH |
626 | /* |
627 | * We need saved copies of a number of fields - this is because | |
628 | * error handling may need to overwrite these with different values | |
629 | * to run different commands, and once error handling is complete, | |
630 | * we will need to restore these values prior to running the actual | |
631 | * command. | |
632 | */ | |
633 | old_buffer = scmd->request_buffer; | |
634 | old_bufflen = scmd->request_bufflen; | |
635 | memcpy(old_cmnd, scmd->cmnd, sizeof(scmd->cmnd)); | |
636 | old_data_direction = scmd->sc_data_direction; | |
637 | old_cmd_len = scmd->cmd_len; | |
638 | old_use_sg = scmd->use_sg; | |
639 | ||
0db99e33 MC |
640 | memset(scmd->cmnd, 0, sizeof(scmd->cmnd)); |
641 | memcpy(scmd->cmnd, cmnd, cmnd_size); | |
642 | ||
631c228c | 643 | if (copy_sense) { |
fa1f5ea8 | 644 | gfp_t gfp_mask = GFP_ATOMIC; |
631c228c CH |
645 | |
646 | if (shost->hostt->unchecked_isa_dma) | |
647 | gfp_mask |= __GFP_DMA; | |
648 | ||
2dc611de CH |
649 | sgl.page = alloc_page(gfp_mask); |
650 | if (!sgl.page) | |
631c228c | 651 | return FAILED; |
2dc611de CH |
652 | sgl.offset = 0; |
653 | sgl.length = 252; | |
654 | ||
655 | scmd->sc_data_direction = DMA_FROM_DEVICE; | |
656 | scmd->request_bufflen = sgl.length; | |
657 | scmd->request_buffer = &sgl; | |
658 | scmd->use_sg = 1; | |
631c228c CH |
659 | } else { |
660 | scmd->request_buffer = NULL; | |
661 | scmd->request_bufflen = 0; | |
662 | scmd->sc_data_direction = DMA_NONE; | |
2dc611de | 663 | scmd->use_sg = 0; |
631c228c CH |
664 | } |
665 | ||
666 | scmd->underflow = 0; | |
631c228c CH |
667 | scmd->cmd_len = COMMAND_SIZE(scmd->cmnd[0]); |
668 | ||
f59114b7 | 669 | if (sdev->scsi_level <= SCSI_2) |
1da177e4 | 670 | scmd->cmnd[1] = (scmd->cmnd[1] & 0x1f) | |
f59114b7 | 671 | (sdev->lun << 5 & 0xe0); |
1da177e4 | 672 | |
631c228c CH |
673 | /* |
674 | * Zero the sense buffer. The scsi spec mandates that any | |
675 | * untransferred sense data should be interpreted as being zero. | |
676 | */ | |
677 | memset(scmd->sense_buffer, 0, sizeof(scmd->sense_buffer)); | |
678 | ||
7dfdc9a5 | 679 | shost->eh_action = &done; |
1da177e4 | 680 | |
f59114b7 | 681 | spin_lock_irqsave(shost->host_lock, flags); |
1da177e4 | 682 | scsi_log_send(scmd); |
f59114b7 | 683 | shost->hostt->queuecommand(scmd, scsi_eh_done); |
684 | spin_unlock_irqrestore(shost->host_lock, flags); | |
1da177e4 | 685 | |
7dfdc9a5 | 686 | timeleft = wait_for_completion_timeout(&done, timeout); |
1da177e4 | 687 | |
f59114b7 | 688 | shost->eh_action = NULL; |
1da177e4 | 689 | |
7dfdc9a5 | 690 | scsi_log_completion(scmd, SUCCESS); |
1da177e4 | 691 | |
7dfdc9a5 CH |
692 | SCSI_LOG_ERROR_RECOVERY(3, |
693 | printk("%s: scmd: %p, timeleft: %ld\n", | |
694 | __FUNCTION__, scmd, timeleft)); | |
1da177e4 LT |
695 | |
696 | /* | |
7dfdc9a5 CH |
697 | * If there is time left scsi_eh_done got called, and we will |
698 | * examine the actual status codes to see whether the command | |
699 | * actually did complete normally, else tell the host to forget | |
700 | * about this command. | |
1da177e4 | 701 | */ |
7dfdc9a5 | 702 | if (timeleft) { |
1da177e4 LT |
703 | rtn = scsi_eh_completed_normally(scmd); |
704 | SCSI_LOG_ERROR_RECOVERY(3, | |
705 | printk("%s: scsi_eh_completed_normally %x\n", | |
706 | __FUNCTION__, rtn)); | |
7dfdc9a5 | 707 | |
1da177e4 LT |
708 | switch (rtn) { |
709 | case SUCCESS: | |
710 | case NEEDS_RETRY: | |
711 | case FAILED: | |
712 | break; | |
713 | default: | |
714 | rtn = FAILED; | |
715 | break; | |
716 | } | |
7dfdc9a5 | 717 | } else { |
292148f8 | 718 | scsi_abort_eh_cmnd(scmd); |
7dfdc9a5 | 719 | rtn = FAILED; |
1da177e4 LT |
720 | } |
721 | ||
631c228c CH |
722 | |
723 | /* | |
724 | * Last chance to have valid sense data. | |
725 | */ | |
726 | if (copy_sense) { | |
727 | if (!SCSI_SENSE_VALID(scmd)) { | |
728 | memcpy(scmd->sense_buffer, scmd->request_buffer, | |
729 | sizeof(scmd->sense_buffer)); | |
730 | } | |
2dc611de | 731 | __free_page(sgl.page); |
631c228c CH |
732 | } |
733 | ||
734 | ||
735 | /* | |
736 | * Restore original data | |
737 | */ | |
738 | scmd->request_buffer = old_buffer; | |
739 | scmd->request_bufflen = old_bufflen; | |
740 | memcpy(scmd->cmnd, old_cmnd, sizeof(scmd->cmnd)); | |
741 | scmd->sc_data_direction = old_data_direction; | |
742 | scmd->cmd_len = old_cmd_len; | |
743 | scmd->use_sg = old_use_sg; | |
744 | scmd->result = old_result; | |
1da177e4 LT |
745 | return rtn; |
746 | } | |
747 | ||
748 | /** | |
749 | * scsi_request_sense - Request sense data from a particular target. | |
750 | * @scmd: SCSI cmd for request sense. | |
751 | * | |
752 | * Notes: | |
753 | * Some hosts automatically obtain this information, others require | |
754 | * that we obtain it on our own. This function will *not* return until | |
755 | * the command either times out, or it completes. | |
756 | **/ | |
757 | static int scsi_request_sense(struct scsi_cmnd *scmd) | |
758 | { | |
759 | static unsigned char generic_sense[6] = | |
631c228c | 760 | {REQUEST_SENSE, 0, 0, 0, 252, 0}; |
1da177e4 | 761 | |
0db99e33 | 762 | return scsi_send_eh_cmnd(scmd, generic_sense, 6, SENSE_TIMEOUT, 1); |
1da177e4 LT |
763 | } |
764 | ||
765 | /** | |
766 | * scsi_eh_finish_cmd - Handle a cmd that eh is finished with. | |
767 | * @scmd: Original SCSI cmd that eh has finished. | |
768 | * @done_q: Queue for processed commands. | |
769 | * | |
770 | * Notes: | |
771 | * We don't want to use the normal command completion while we are are | |
772 | * still handling errors - it may cause other commands to be queued, | |
773 | * and that would disturb what we are doing. thus we really want to | |
774 | * keep a list of pending commands for final completion, and once we | |
775 | * are ready to leave error handling we handle completion for real. | |
776 | **/ | |
041c5fc3 | 777 | void scsi_eh_finish_cmd(struct scsi_cmnd *scmd, struct list_head *done_q) |
1da177e4 LT |
778 | { |
779 | scmd->device->host->host_failed--; | |
3111b0d1 | 780 | scmd->eh_eflags = 0; |
1da177e4 LT |
781 | list_move_tail(&scmd->eh_entry, done_q); |
782 | } | |
041c5fc3 | 783 | EXPORT_SYMBOL(scsi_eh_finish_cmd); |
1da177e4 LT |
784 | |
785 | /** | |
786 | * scsi_eh_get_sense - Get device sense data. | |
787 | * @work_q: Queue of commands to process. | |
788 | * @done_q: Queue of proccessed commands.. | |
789 | * | |
790 | * Description: | |
791 | * See if we need to request sense information. if so, then get it | |
792 | * now, so we have a better idea of what to do. | |
793 | * | |
794 | * Notes: | |
795 | * This has the unfortunate side effect that if a shost adapter does | |
796 | * not automatically request sense information, that we end up shutting | |
797 | * it down before we request it. | |
798 | * | |
799 | * All drivers should request sense information internally these days, | |
800 | * so for now all I have to say is tough noogies if you end up in here. | |
801 | * | |
802 | * XXX: Long term this code should go away, but that needs an audit of | |
803 | * all LLDDs first. | |
804 | **/ | |
dca84e46 DW |
805 | int scsi_eh_get_sense(struct list_head *work_q, |
806 | struct list_head *done_q) | |
1da177e4 | 807 | { |
937abeaa | 808 | struct scsi_cmnd *scmd, *next; |
1da177e4 LT |
809 | int rtn; |
810 | ||
937abeaa | 811 | list_for_each_entry_safe(scmd, next, work_q, eh_entry) { |
3111b0d1 | 812 | if ((scmd->eh_eflags & SCSI_EH_CANCEL_CMD) || |
1da177e4 LT |
813 | SCSI_SENSE_VALID(scmd)) |
814 | continue; | |
815 | ||
3bf743e7 JG |
816 | SCSI_LOG_ERROR_RECOVERY(2, scmd_printk(KERN_INFO, scmd, |
817 | "%s: requesting sense\n", | |
818 | current->comm)); | |
1da177e4 LT |
819 | rtn = scsi_request_sense(scmd); |
820 | if (rtn != SUCCESS) | |
821 | continue; | |
822 | ||
823 | SCSI_LOG_ERROR_RECOVERY(3, printk("sense requested for %p" | |
824 | " result %x\n", scmd, | |
825 | scmd->result)); | |
826 | SCSI_LOG_ERROR_RECOVERY(3, scsi_print_sense("bh", scmd)); | |
827 | ||
828 | rtn = scsi_decide_disposition(scmd); | |
829 | ||
830 | /* | |
831 | * if the result was normal, then just pass it along to the | |
832 | * upper level. | |
833 | */ | |
834 | if (rtn == SUCCESS) | |
835 | /* we don't want this command reissued, just | |
836 | * finished with the sense data, so set | |
837 | * retries to the max allowed to ensure it | |
838 | * won't get reissued */ | |
839 | scmd->retries = scmd->allowed; | |
840 | else if (rtn != NEEDS_RETRY) | |
841 | continue; | |
842 | ||
843 | scsi_eh_finish_cmd(scmd, done_q); | |
844 | } | |
845 | ||
846 | return list_empty(work_q); | |
847 | } | |
dca84e46 | 848 | EXPORT_SYMBOL_GPL(scsi_eh_get_sense); |
1da177e4 | 849 | |
1da177e4 LT |
850 | /** |
851 | * scsi_eh_tur - Send TUR to device. | |
852 | * @scmd: Scsi cmd to send TUR | |
853 | * | |
854 | * Return value: | |
855 | * 0 - Device is ready. 1 - Device NOT ready. | |
856 | **/ | |
857 | static int scsi_eh_tur(struct scsi_cmnd *scmd) | |
858 | { | |
859 | static unsigned char tur_command[6] = {TEST_UNIT_READY, 0, 0, 0, 0, 0}; | |
860 | int retry_cnt = 1, rtn; | |
861 | ||
862 | retry_tur: | |
0db99e33 | 863 | rtn = scsi_send_eh_cmnd(scmd, tur_command, 6, SENSE_TIMEOUT, 0); |
1da177e4 | 864 | |
1da177e4 LT |
865 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: scmd %p rtn %x\n", |
866 | __FUNCTION__, scmd, rtn)); | |
631c228c CH |
867 | |
868 | switch (rtn) { | |
869 | case NEEDS_RETRY: | |
1da177e4 LT |
870 | if (retry_cnt--) |
871 | goto retry_tur; | |
631c228c CH |
872 | /*FALLTHRU*/ |
873 | case SUCCESS: | |
e47373ec | 874 | return 0; |
631c228c CH |
875 | default: |
876 | return 1; | |
e47373ec | 877 | } |
1da177e4 LT |
878 | } |
879 | ||
880 | /** | |
881 | * scsi_eh_abort_cmds - abort canceled commands. | |
882 | * @shost: scsi host being recovered. | |
883 | * @eh_done_q: list_head for processed commands. | |
884 | * | |
885 | * Decription: | |
886 | * Try and see whether or not it makes sense to try and abort the | |
887 | * running command. this only works out to be the case if we have one | |
888 | * command that has timed out. if the command simply failed, it makes | |
889 | * no sense to try and abort the command, since as far as the shost | |
890 | * adapter is concerned, it isn't running. | |
891 | **/ | |
892 | static int scsi_eh_abort_cmds(struct list_head *work_q, | |
893 | struct list_head *done_q) | |
894 | { | |
937abeaa | 895 | struct scsi_cmnd *scmd, *next; |
1da177e4 LT |
896 | int rtn; |
897 | ||
937abeaa | 898 | list_for_each_entry_safe(scmd, next, work_q, eh_entry) { |
3111b0d1 | 899 | if (!(scmd->eh_eflags & SCSI_EH_CANCEL_CMD)) |
1da177e4 LT |
900 | continue; |
901 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: aborting cmd:" | |
902 | "0x%p\n", current->comm, | |
903 | scmd)); | |
904 | rtn = scsi_try_to_abort_cmd(scmd); | |
905 | if (rtn == SUCCESS) { | |
3111b0d1 | 906 | scmd->eh_eflags &= ~SCSI_EH_CANCEL_CMD; |
1da177e4 LT |
907 | if (!scsi_device_online(scmd->device) || |
908 | !scsi_eh_tur(scmd)) { | |
909 | scsi_eh_finish_cmd(scmd, done_q); | |
910 | } | |
911 | ||
912 | } else | |
913 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: aborting" | |
914 | " cmd failed:" | |
915 | "0x%p\n", | |
916 | current->comm, | |
917 | scmd)); | |
918 | } | |
919 | ||
920 | return list_empty(work_q); | |
921 | } | |
922 | ||
1da177e4 LT |
923 | /** |
924 | * scsi_eh_try_stu - Send START_UNIT to device. | |
925 | * @scmd: Scsi cmd to send START_UNIT | |
926 | * | |
927 | * Return value: | |
928 | * 0 - Device is ready. 1 - Device NOT ready. | |
929 | **/ | |
930 | static int scsi_eh_try_stu(struct scsi_cmnd *scmd) | |
931 | { | |
932 | static unsigned char stu_command[6] = {START_STOP, 0, 0, 0, 1, 0}; | |
1da177e4 | 933 | |
631c228c CH |
934 | if (scmd->device->allow_restart) { |
935 | int rtn; | |
1da177e4 | 936 | |
0db99e33 MC |
937 | rtn = scsi_send_eh_cmnd(scmd, stu_command, 6, |
938 | START_UNIT_TIMEOUT, 0); | |
631c228c CH |
939 | if (rtn == SUCCESS) |
940 | return 0; | |
941 | } | |
1da177e4 | 942 | |
1da177e4 LT |
943 | return 1; |
944 | } | |
945 | ||
946 | /** | |
947 | * scsi_eh_stu - send START_UNIT if needed | |
948 | * @shost: scsi host being recovered. | |
949 | * @eh_done_q: list_head for processed commands. | |
950 | * | |
951 | * Notes: | |
952 | * If commands are failing due to not ready, initializing command required, | |
953 | * try revalidating the device, which will end up sending a start unit. | |
954 | **/ | |
955 | static int scsi_eh_stu(struct Scsi_Host *shost, | |
956 | struct list_head *work_q, | |
957 | struct list_head *done_q) | |
958 | { | |
937abeaa | 959 | struct scsi_cmnd *scmd, *stu_scmd, *next; |
1da177e4 LT |
960 | struct scsi_device *sdev; |
961 | ||
962 | shost_for_each_device(sdev, shost) { | |
963 | stu_scmd = NULL; | |
964 | list_for_each_entry(scmd, work_q, eh_entry) | |
965 | if (scmd->device == sdev && SCSI_SENSE_VALID(scmd) && | |
966 | scsi_check_sense(scmd) == FAILED ) { | |
967 | stu_scmd = scmd; | |
968 | break; | |
969 | } | |
970 | ||
971 | if (!stu_scmd) | |
972 | continue; | |
973 | ||
974 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending START_UNIT to sdev:" | |
975 | " 0x%p\n", current->comm, sdev)); | |
976 | ||
977 | if (!scsi_eh_try_stu(stu_scmd)) { | |
978 | if (!scsi_device_online(sdev) || | |
979 | !scsi_eh_tur(stu_scmd)) { | |
937abeaa CH |
980 | list_for_each_entry_safe(scmd, next, |
981 | work_q, eh_entry) { | |
1da177e4 LT |
982 | if (scmd->device == sdev) |
983 | scsi_eh_finish_cmd(scmd, done_q); | |
984 | } | |
985 | } | |
986 | } else { | |
987 | SCSI_LOG_ERROR_RECOVERY(3, | |
988 | printk("%s: START_UNIT failed to sdev:" | |
989 | " 0x%p\n", current->comm, sdev)); | |
990 | } | |
991 | } | |
992 | ||
993 | return list_empty(work_q); | |
994 | } | |
995 | ||
996 | ||
997 | /** | |
998 | * scsi_eh_bus_device_reset - send bdr if needed | |
999 | * @shost: scsi host being recovered. | |
1000 | * @eh_done_q: list_head for processed commands. | |
1001 | * | |
1002 | * Notes: | |
1003 | * Try a bus device reset. still, look to see whether we have multiple | |
1004 | * devices that are jammed or not - if we have multiple devices, it | |
1005 | * makes no sense to try bus_device_reset - we really would need to try | |
1006 | * a bus_reset instead. | |
1007 | **/ | |
1008 | static int scsi_eh_bus_device_reset(struct Scsi_Host *shost, | |
1009 | struct list_head *work_q, | |
1010 | struct list_head *done_q) | |
1011 | { | |
937abeaa | 1012 | struct scsi_cmnd *scmd, *bdr_scmd, *next; |
1da177e4 LT |
1013 | struct scsi_device *sdev; |
1014 | int rtn; | |
1015 | ||
1016 | shost_for_each_device(sdev, shost) { | |
1017 | bdr_scmd = NULL; | |
1018 | list_for_each_entry(scmd, work_q, eh_entry) | |
1019 | if (scmd->device == sdev) { | |
1020 | bdr_scmd = scmd; | |
1021 | break; | |
1022 | } | |
1023 | ||
1024 | if (!bdr_scmd) | |
1025 | continue; | |
1026 | ||
1027 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending BDR sdev:" | |
1028 | " 0x%p\n", current->comm, | |
1029 | sdev)); | |
1030 | rtn = scsi_try_bus_device_reset(bdr_scmd); | |
1031 | if (rtn == SUCCESS) { | |
1032 | if (!scsi_device_online(sdev) || | |
1033 | !scsi_eh_tur(bdr_scmd)) { | |
937abeaa CH |
1034 | list_for_each_entry_safe(scmd, next, |
1035 | work_q, eh_entry) { | |
1da177e4 LT |
1036 | if (scmd->device == sdev) |
1037 | scsi_eh_finish_cmd(scmd, | |
1038 | done_q); | |
1039 | } | |
1040 | } | |
1041 | } else { | |
1042 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: BDR" | |
1043 | " failed sdev:" | |
1044 | "0x%p\n", | |
1045 | current->comm, | |
1046 | sdev)); | |
1047 | } | |
1048 | } | |
1049 | ||
1050 | return list_empty(work_q); | |
1051 | } | |
1052 | ||
1da177e4 LT |
1053 | /** |
1054 | * scsi_eh_bus_reset - send a bus reset | |
1055 | * @shost: scsi host being recovered. | |
1056 | * @eh_done_q: list_head for processed commands. | |
1057 | **/ | |
1058 | static int scsi_eh_bus_reset(struct Scsi_Host *shost, | |
1059 | struct list_head *work_q, | |
1060 | struct list_head *done_q) | |
1061 | { | |
937abeaa | 1062 | struct scsi_cmnd *scmd, *chan_scmd, *next; |
1da177e4 LT |
1063 | unsigned int channel; |
1064 | int rtn; | |
1065 | ||
1066 | /* | |
1067 | * we really want to loop over the various channels, and do this on | |
1068 | * a channel by channel basis. we should also check to see if any | |
1069 | * of the failed commands are on soft_reset devices, and if so, skip | |
1070 | * the reset. | |
1071 | */ | |
1072 | ||
1073 | for (channel = 0; channel <= shost->max_channel; channel++) { | |
1074 | chan_scmd = NULL; | |
1075 | list_for_each_entry(scmd, work_q, eh_entry) { | |
422c0d61 | 1076 | if (channel == scmd_channel(scmd)) { |
1da177e4 LT |
1077 | chan_scmd = scmd; |
1078 | break; | |
1079 | /* | |
1080 | * FIXME add back in some support for | |
1081 | * soft_reset devices. | |
1082 | */ | |
1083 | } | |
1084 | } | |
1085 | ||
1086 | if (!chan_scmd) | |
1087 | continue; | |
1088 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending BRST chan:" | |
1089 | " %d\n", current->comm, | |
1090 | channel)); | |
1091 | rtn = scsi_try_bus_reset(chan_scmd); | |
1092 | if (rtn == SUCCESS) { | |
937abeaa | 1093 | list_for_each_entry_safe(scmd, next, work_q, eh_entry) { |
422c0d61 | 1094 | if (channel == scmd_channel(scmd)) |
1da177e4 LT |
1095 | if (!scsi_device_online(scmd->device) || |
1096 | !scsi_eh_tur(scmd)) | |
1097 | scsi_eh_finish_cmd(scmd, | |
1098 | done_q); | |
1099 | } | |
1100 | } else { | |
1101 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: BRST" | |
1102 | " failed chan: %d\n", | |
1103 | current->comm, | |
1104 | channel)); | |
1105 | } | |
1106 | } | |
1107 | return list_empty(work_q); | |
1108 | } | |
1109 | ||
1110 | /** | |
1111 | * scsi_eh_host_reset - send a host reset | |
1112 | * @work_q: list_head for processed commands. | |
1113 | * @done_q: list_head for processed commands. | |
1114 | **/ | |
1115 | static int scsi_eh_host_reset(struct list_head *work_q, | |
1116 | struct list_head *done_q) | |
1117 | { | |
937abeaa | 1118 | struct scsi_cmnd *scmd, *next; |
1da177e4 | 1119 | int rtn; |
1da177e4 LT |
1120 | |
1121 | if (!list_empty(work_q)) { | |
1122 | scmd = list_entry(work_q->next, | |
1123 | struct scsi_cmnd, eh_entry); | |
1124 | ||
1125 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending HRST\n" | |
1126 | , current->comm)); | |
1127 | ||
1128 | rtn = scsi_try_host_reset(scmd); | |
1129 | if (rtn == SUCCESS) { | |
937abeaa | 1130 | list_for_each_entry_safe(scmd, next, work_q, eh_entry) { |
1da177e4 LT |
1131 | if (!scsi_device_online(scmd->device) || |
1132 | (!scsi_eh_try_stu(scmd) && !scsi_eh_tur(scmd)) || | |
1133 | !scsi_eh_tur(scmd)) | |
1134 | scsi_eh_finish_cmd(scmd, done_q); | |
1135 | } | |
1136 | } else { | |
1137 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: HRST" | |
1138 | " failed\n", | |
1139 | current->comm)); | |
1140 | } | |
1141 | } | |
1142 | return list_empty(work_q); | |
1143 | } | |
1144 | ||
1145 | /** | |
1146 | * scsi_eh_offline_sdevs - offline scsi devices that fail to recover | |
1147 | * @work_q: list_head for processed commands. | |
1148 | * @done_q: list_head for processed commands. | |
1149 | * | |
1150 | **/ | |
1151 | static void scsi_eh_offline_sdevs(struct list_head *work_q, | |
1152 | struct list_head *done_q) | |
1153 | { | |
937abeaa | 1154 | struct scsi_cmnd *scmd, *next; |
1da177e4 | 1155 | |
937abeaa | 1156 | list_for_each_entry_safe(scmd, next, work_q, eh_entry) { |
9ccfc756 JB |
1157 | sdev_printk(KERN_INFO, scmd->device, |
1158 | "scsi: Device offlined - not" | |
1159 | " ready after error recovery\n"); | |
1da177e4 | 1160 | scsi_device_set_state(scmd->device, SDEV_OFFLINE); |
3111b0d1 | 1161 | if (scmd->eh_eflags & SCSI_EH_CANCEL_CMD) { |
1da177e4 LT |
1162 | /* |
1163 | * FIXME: Handle lost cmds. | |
1164 | */ | |
1165 | } | |
1166 | scsi_eh_finish_cmd(scmd, done_q); | |
1167 | } | |
1168 | return; | |
1169 | } | |
1170 | ||
1171 | /** | |
1172 | * scsi_decide_disposition - Disposition a cmd on return from LLD. | |
1173 | * @scmd: SCSI cmd to examine. | |
1174 | * | |
1175 | * Notes: | |
1176 | * This is *only* called when we are examining the status after sending | |
1177 | * out the actual data command. any commands that are queued for error | |
1178 | * recovery (e.g. test_unit_ready) do *not* come through here. | |
1179 | * | |
1180 | * When this routine returns failed, it means the error handler thread | |
1181 | * is woken. In cases where the error code indicates an error that | |
1182 | * doesn't require the error handler read (i.e. we don't need to | |
1183 | * abort/reset), this function should return SUCCESS. | |
1184 | **/ | |
1185 | int scsi_decide_disposition(struct scsi_cmnd *scmd) | |
1186 | { | |
1187 | int rtn; | |
1188 | ||
1189 | /* | |
1190 | * if the device is offline, then we clearly just pass the result back | |
1191 | * up to the top level. | |
1192 | */ | |
1193 | if (!scsi_device_online(scmd->device)) { | |
1194 | SCSI_LOG_ERROR_RECOVERY(5, printk("%s: device offline - report" | |
1195 | " as SUCCESS\n", | |
1196 | __FUNCTION__)); | |
1197 | return SUCCESS; | |
1198 | } | |
1199 | ||
1200 | /* | |
1201 | * first check the host byte, to see if there is anything in there | |
1202 | * that would indicate what we need to do. | |
1203 | */ | |
1204 | switch (host_byte(scmd->result)) { | |
1205 | case DID_PASSTHROUGH: | |
1206 | /* | |
1207 | * no matter what, pass this through to the upper layer. | |
1208 | * nuke this special code so that it looks like we are saying | |
1209 | * did_ok. | |
1210 | */ | |
1211 | scmd->result &= 0xff00ffff; | |
1212 | return SUCCESS; | |
1213 | case DID_OK: | |
1214 | /* | |
1215 | * looks good. drop through, and check the next byte. | |
1216 | */ | |
1217 | break; | |
1218 | case DID_NO_CONNECT: | |
1219 | case DID_BAD_TARGET: | |
1220 | case DID_ABORT: | |
1221 | /* | |
1222 | * note - this means that we just report the status back | |
1223 | * to the top level driver, not that we actually think | |
1224 | * that it indicates SUCCESS. | |
1225 | */ | |
1226 | return SUCCESS; | |
1227 | /* | |
1228 | * when the low level driver returns did_soft_error, | |
1229 | * it is responsible for keeping an internal retry counter | |
1230 | * in order to avoid endless loops (db) | |
1231 | * | |
1232 | * actually this is a bug in this function here. we should | |
1233 | * be mindful of the maximum number of retries specified | |
1234 | * and not get stuck in a loop. | |
1235 | */ | |
1236 | case DID_SOFT_ERROR: | |
1237 | goto maybe_retry; | |
1238 | case DID_IMM_RETRY: | |
1239 | return NEEDS_RETRY; | |
1240 | ||
bf341919 | 1241 | case DID_REQUEUE: |
1242 | return ADD_TO_MLQUEUE; | |
1243 | ||
1da177e4 LT |
1244 | case DID_ERROR: |
1245 | if (msg_byte(scmd->result) == COMMAND_COMPLETE && | |
1246 | status_byte(scmd->result) == RESERVATION_CONFLICT) | |
1247 | /* | |
1248 | * execute reservation conflict processing code | |
1249 | * lower down | |
1250 | */ | |
1251 | break; | |
1252 | /* fallthrough */ | |
1253 | ||
1254 | case DID_BUS_BUSY: | |
1255 | case DID_PARITY: | |
1256 | goto maybe_retry; | |
1257 | case DID_TIME_OUT: | |
1258 | /* | |
1259 | * when we scan the bus, we get timeout messages for | |
1260 | * these commands if there is no device available. | |
1261 | * other hosts report did_no_connect for the same thing. | |
1262 | */ | |
1263 | if ((scmd->cmnd[0] == TEST_UNIT_READY || | |
1264 | scmd->cmnd[0] == INQUIRY)) { | |
1265 | return SUCCESS; | |
1266 | } else { | |
1267 | return FAILED; | |
1268 | } | |
1269 | case DID_RESET: | |
1270 | return SUCCESS; | |
1271 | default: | |
1272 | return FAILED; | |
1273 | } | |
1274 | ||
1275 | /* | |
1276 | * next, check the message byte. | |
1277 | */ | |
1278 | if (msg_byte(scmd->result) != COMMAND_COMPLETE) | |
1279 | return FAILED; | |
1280 | ||
1281 | /* | |
1282 | * check the status byte to see if this indicates anything special. | |
1283 | */ | |
1284 | switch (status_byte(scmd->result)) { | |
1285 | case QUEUE_FULL: | |
1286 | /* | |
1287 | * the case of trying to send too many commands to a | |
1288 | * tagged queueing device. | |
1289 | */ | |
1290 | case BUSY: | |
1291 | /* | |
1292 | * device can't talk to us at the moment. Should only | |
1293 | * occur (SAM-3) when the task queue is empty, so will cause | |
1294 | * the empty queue handling to trigger a stall in the | |
1295 | * device. | |
1296 | */ | |
1297 | return ADD_TO_MLQUEUE; | |
1298 | case GOOD: | |
1299 | case COMMAND_TERMINATED: | |
1300 | case TASK_ABORTED: | |
1301 | return SUCCESS; | |
1302 | case CHECK_CONDITION: | |
1303 | rtn = scsi_check_sense(scmd); | |
1304 | if (rtn == NEEDS_RETRY) | |
1305 | goto maybe_retry; | |
1306 | /* if rtn == FAILED, we have no sense information; | |
1307 | * returning FAILED will wake the error handler thread | |
1308 | * to collect the sense and redo the decide | |
1309 | * disposition */ | |
1310 | return rtn; | |
1311 | case CONDITION_GOOD: | |
1312 | case INTERMEDIATE_GOOD: | |
1313 | case INTERMEDIATE_C_GOOD: | |
1314 | case ACA_ACTIVE: | |
1315 | /* | |
1316 | * who knows? FIXME(eric) | |
1317 | */ | |
1318 | return SUCCESS; | |
1319 | ||
1320 | case RESERVATION_CONFLICT: | |
9ccfc756 JB |
1321 | sdev_printk(KERN_INFO, scmd->device, |
1322 | "reservation conflict\n"); | |
1da177e4 LT |
1323 | return SUCCESS; /* causes immediate i/o error */ |
1324 | default: | |
1325 | return FAILED; | |
1326 | } | |
1327 | return FAILED; | |
1328 | ||
1329 | maybe_retry: | |
1330 | ||
1331 | /* we requeue for retry because the error was retryable, and | |
1332 | * the request was not marked fast fail. Note that above, | |
1333 | * even if the request is marked fast fail, we still requeue | |
1334 | * for queue congestion conditions (QUEUE_FULL or BUSY) */ | |
8884efab | 1335 | if ((++scmd->retries) <= scmd->allowed |
1da177e4 LT |
1336 | && !blk_noretry_request(scmd->request)) { |
1337 | return NEEDS_RETRY; | |
1338 | } else { | |
1339 | /* | |
1340 | * no more retries - report this one back to upper level. | |
1341 | */ | |
1342 | return SUCCESS; | |
1343 | } | |
1344 | } | |
1345 | ||
1da177e4 LT |
1346 | /** |
1347 | * scsi_eh_lock_door - Prevent medium removal for the specified device | |
1348 | * @sdev: SCSI device to prevent medium removal | |
1349 | * | |
1350 | * Locking: | |
1351 | * We must be called from process context; scsi_allocate_request() | |
1352 | * may sleep. | |
1353 | * | |
1354 | * Notes: | |
1355 | * We queue up an asynchronous "ALLOW MEDIUM REMOVAL" request on the | |
1356 | * head of the devices request queue, and continue. | |
1357 | * | |
1358 | * Bugs: | |
1359 | * scsi_allocate_request() may sleep waiting for existing requests to | |
1360 | * be processed. However, since we haven't kicked off any request | |
1361 | * processing for this host, this may deadlock. | |
1362 | * | |
1363 | * If scsi_allocate_request() fails for what ever reason, we | |
1364 | * completely forget to lock the door. | |
1365 | **/ | |
1366 | static void scsi_eh_lock_door(struct scsi_device *sdev) | |
1367 | { | |
6e68af66 | 1368 | unsigned char cmnd[MAX_COMMAND_SIZE]; |
1da177e4 | 1369 | |
6e68af66 MC |
1370 | cmnd[0] = ALLOW_MEDIUM_REMOVAL; |
1371 | cmnd[1] = 0; | |
1372 | cmnd[2] = 0; | |
1373 | cmnd[3] = 0; | |
1374 | cmnd[4] = SCSI_REMOVAL_PREVENT; | |
1375 | cmnd[5] = 0; | |
1da177e4 | 1376 | |
bb1d1073 | 1377 | scsi_execute_async(sdev, cmnd, 6, DMA_NONE, NULL, 0, 0, 10 * HZ, |
6e68af66 | 1378 | 5, NULL, NULL, GFP_KERNEL); |
1da177e4 LT |
1379 | } |
1380 | ||
1381 | ||
1382 | /** | |
1383 | * scsi_restart_operations - restart io operations to the specified host. | |
1384 | * @shost: Host we are restarting. | |
1385 | * | |
1386 | * Notes: | |
1387 | * When we entered the error handler, we blocked all further i/o to | |
1388 | * this device. we need to 'reverse' this process. | |
1389 | **/ | |
1390 | static void scsi_restart_operations(struct Scsi_Host *shost) | |
1391 | { | |
1392 | struct scsi_device *sdev; | |
939647ee | 1393 | unsigned long flags; |
1da177e4 LT |
1394 | |
1395 | /* | |
1396 | * If the door was locked, we need to insert a door lock request | |
1397 | * onto the head of the SCSI request queue for the device. There | |
1398 | * is no point trying to lock the door of an off-line device. | |
1399 | */ | |
1400 | shost_for_each_device(sdev, shost) { | |
1401 | if (scsi_device_online(sdev) && sdev->locked) | |
1402 | scsi_eh_lock_door(sdev); | |
1403 | } | |
1404 | ||
1405 | /* | |
1406 | * next free up anything directly waiting upon the host. this | |
1407 | * will be requests for character device operations, and also for | |
1408 | * ioctls to queued block devices. | |
1409 | */ | |
1410 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: waking up host to restart\n", | |
1411 | __FUNCTION__)); | |
1412 | ||
939647ee JB |
1413 | spin_lock_irqsave(shost->host_lock, flags); |
1414 | if (scsi_host_set_state(shost, SHOST_RUNNING)) | |
1415 | if (scsi_host_set_state(shost, SHOST_CANCEL)) | |
1416 | BUG_ON(scsi_host_set_state(shost, SHOST_DEL)); | |
1417 | spin_unlock_irqrestore(shost->host_lock, flags); | |
1da177e4 LT |
1418 | |
1419 | wake_up(&shost->host_wait); | |
1420 | ||
1421 | /* | |
1422 | * finally we need to re-initiate requests that may be pending. we will | |
1423 | * have had everything blocked while error handling is taking place, and | |
1424 | * now that error recovery is done, we will need to ensure that these | |
1425 | * requests are started. | |
1426 | */ | |
1427 | scsi_run_host_queues(shost); | |
1428 | } | |
1429 | ||
1430 | /** | |
1431 | * scsi_eh_ready_devs - check device ready state and recover if not. | |
1432 | * @shost: host to be recovered. | |
1433 | * @eh_done_q: list_head for processed commands. | |
1434 | * | |
1435 | **/ | |
dca84e46 DW |
1436 | void scsi_eh_ready_devs(struct Scsi_Host *shost, |
1437 | struct list_head *work_q, | |
1438 | struct list_head *done_q) | |
1da177e4 LT |
1439 | { |
1440 | if (!scsi_eh_stu(shost, work_q, done_q)) | |
1441 | if (!scsi_eh_bus_device_reset(shost, work_q, done_q)) | |
1442 | if (!scsi_eh_bus_reset(shost, work_q, done_q)) | |
1443 | if (!scsi_eh_host_reset(work_q, done_q)) | |
1444 | scsi_eh_offline_sdevs(work_q, done_q); | |
1445 | } | |
dca84e46 | 1446 | EXPORT_SYMBOL_GPL(scsi_eh_ready_devs); |
1da177e4 LT |
1447 | |
1448 | /** | |
1449 | * scsi_eh_flush_done_q - finish processed commands or retry them. | |
1450 | * @done_q: list_head of processed commands. | |
1451 | * | |
1452 | **/ | |
041c5fc3 | 1453 | void scsi_eh_flush_done_q(struct list_head *done_q) |
1da177e4 | 1454 | { |
937abeaa | 1455 | struct scsi_cmnd *scmd, *next; |
1da177e4 | 1456 | |
937abeaa CH |
1457 | list_for_each_entry_safe(scmd, next, done_q, eh_entry) { |
1458 | list_del_init(&scmd->eh_entry); | |
1da177e4 LT |
1459 | if (scsi_device_online(scmd->device) && |
1460 | !blk_noretry_request(scmd->request) && | |
8884efab | 1461 | (++scmd->retries <= scmd->allowed)) { |
1da177e4 LT |
1462 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: flush" |
1463 | " retry cmd: %p\n", | |
1464 | current->comm, | |
1465 | scmd)); | |
1466 | scsi_queue_insert(scmd, SCSI_MLQUEUE_EH_RETRY); | |
1467 | } else { | |
793698ce PM |
1468 | /* |
1469 | * If just we got sense for the device (called | |
1470 | * scsi_eh_get_sense), scmd->result is already | |
1471 | * set, do not set DRIVER_TIMEOUT. | |
1472 | */ | |
1da177e4 LT |
1473 | if (!scmd->result) |
1474 | scmd->result |= (DRIVER_TIMEOUT << 24); | |
1475 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: flush finish" | |
1476 | " cmd: %p\n", | |
1477 | current->comm, scmd)); | |
1478 | scsi_finish_command(scmd); | |
1479 | } | |
1480 | } | |
1481 | } | |
041c5fc3 | 1482 | EXPORT_SYMBOL(scsi_eh_flush_done_q); |
1da177e4 LT |
1483 | |
1484 | /** | |
1485 | * scsi_unjam_host - Attempt to fix a host which has a cmd that failed. | |
1486 | * @shost: Host to unjam. | |
1487 | * | |
1488 | * Notes: | |
1489 | * When we come in here, we *know* that all commands on the bus have | |
1490 | * either completed, failed or timed out. we also know that no further | |
1491 | * commands are being sent to the host, so things are relatively quiet | |
1492 | * and we have freedom to fiddle with things as we wish. | |
1493 | * | |
1494 | * This is only the *default* implementation. it is possible for | |
1495 | * individual drivers to supply their own version of this function, and | |
1496 | * if the maintainer wishes to do this, it is strongly suggested that | |
1497 | * this function be taken as a template and modified. this function | |
1498 | * was designed to correctly handle problems for about 95% of the | |
1499 | * different cases out there, and it should always provide at least a | |
1500 | * reasonable amount of error recovery. | |
1501 | * | |
1502 | * Any command marked 'failed' or 'timeout' must eventually have | |
1503 | * scsi_finish_cmd() called for it. we do all of the retry stuff | |
1504 | * here, so when we restart the host after we return it should have an | |
1505 | * empty queue. | |
1506 | **/ | |
1507 | static void scsi_unjam_host(struct Scsi_Host *shost) | |
1508 | { | |
1509 | unsigned long flags; | |
1510 | LIST_HEAD(eh_work_q); | |
1511 | LIST_HEAD(eh_done_q); | |
1512 | ||
1513 | spin_lock_irqsave(shost->host_lock, flags); | |
1514 | list_splice_init(&shost->eh_cmd_q, &eh_work_q); | |
1515 | spin_unlock_irqrestore(shost->host_lock, flags); | |
1516 | ||
1517 | SCSI_LOG_ERROR_RECOVERY(1, scsi_eh_prt_fail_stats(shost, &eh_work_q)); | |
1518 | ||
1519 | if (!scsi_eh_get_sense(&eh_work_q, &eh_done_q)) | |
1520 | if (!scsi_eh_abort_cmds(&eh_work_q, &eh_done_q)) | |
1521 | scsi_eh_ready_devs(shost, &eh_work_q, &eh_done_q); | |
1522 | ||
1523 | scsi_eh_flush_done_q(&eh_done_q); | |
1524 | } | |
1525 | ||
1526 | /** | |
ad42eb1b | 1527 | * scsi_error_handler - SCSI error handler thread |
1da177e4 LT |
1528 | * @data: Host for which we are running. |
1529 | * | |
1530 | * Notes: | |
ad42eb1b CH |
1531 | * This is the main error handling loop. This is run as a kernel thread |
1532 | * for every SCSI host and handles all error handling activity. | |
1da177e4 LT |
1533 | **/ |
1534 | int scsi_error_handler(void *data) | |
1535 | { | |
ad42eb1b | 1536 | struct Scsi_Host *shost = data; |
1da177e4 | 1537 | |
1da177e4 | 1538 | current->flags |= PF_NOFREEZE; |
1da177e4 LT |
1539 | |
1540 | /* | |
ad42eb1b CH |
1541 | * We use TASK_INTERRUPTIBLE so that the thread is not |
1542 | * counted against the load average as a running process. | |
1543 | * We never actually get interrupted because kthread_run | |
1544 | * disables singal delivery for the created thread. | |
1da177e4 | 1545 | */ |
3ed7a470 JB |
1546 | set_current_state(TASK_INTERRUPTIBLE); |
1547 | while (!kthread_should_stop()) { | |
ee7863bc | 1548 | if ((shost->host_failed == 0 && shost->host_eh_scheduled == 0) || |
3ed7a470 | 1549 | shost->host_failed != shost->host_busy) { |
ad42eb1b CH |
1550 | SCSI_LOG_ERROR_RECOVERY(1, |
1551 | printk("Error handler scsi_eh_%d sleeping\n", | |
1552 | shost->host_no)); | |
3ed7a470 JB |
1553 | schedule(); |
1554 | set_current_state(TASK_INTERRUPTIBLE); | |
1555 | continue; | |
1556 | } | |
1da177e4 | 1557 | |
3ed7a470 | 1558 | __set_current_state(TASK_RUNNING); |
ad42eb1b CH |
1559 | SCSI_LOG_ERROR_RECOVERY(1, |
1560 | printk("Error handler scsi_eh_%d waking up\n", | |
1561 | shost->host_no)); | |
1da177e4 | 1562 | |
1da177e4 LT |
1563 | /* |
1564 | * We have a host that is failing for some reason. Figure out | |
1565 | * what we need to do to get it up and online again (if we can). | |
1566 | * If we fail, we end up taking the thing offline. | |
1567 | */ | |
9227c33d CH |
1568 | if (shost->transportt->eh_strategy_handler) |
1569 | shost->transportt->eh_strategy_handler(shost); | |
1da177e4 LT |
1570 | else |
1571 | scsi_unjam_host(shost); | |
1572 | ||
1da177e4 LT |
1573 | /* |
1574 | * Note - if the above fails completely, the action is to take | |
1575 | * individual devices offline and flush the queue of any | |
1576 | * outstanding requests that may have been pending. When we | |
1577 | * restart, we restart any I/O to any other devices on the bus | |
1578 | * which are still online. | |
1579 | */ | |
1580 | scsi_restart_operations(shost); | |
3ed7a470 | 1581 | set_current_state(TASK_INTERRUPTIBLE); |
1da177e4 | 1582 | } |
461a0ffb SR |
1583 | __set_current_state(TASK_RUNNING); |
1584 | ||
ad42eb1b CH |
1585 | SCSI_LOG_ERROR_RECOVERY(1, |
1586 | printk("Error handler scsi_eh_%d exiting\n", shost->host_no)); | |
3ed7a470 | 1587 | shost->ehandler = NULL; |
1da177e4 LT |
1588 | return 0; |
1589 | } | |
1590 | ||
1591 | /* | |
1592 | * Function: scsi_report_bus_reset() | |
1593 | * | |
1594 | * Purpose: Utility function used by low-level drivers to report that | |
1595 | * they have observed a bus reset on the bus being handled. | |
1596 | * | |
1597 | * Arguments: shost - Host in question | |
1598 | * channel - channel on which reset was observed. | |
1599 | * | |
1600 | * Returns: Nothing | |
1601 | * | |
1602 | * Lock status: Host lock must be held. | |
1603 | * | |
1604 | * Notes: This only needs to be called if the reset is one which | |
1605 | * originates from an unknown location. Resets originated | |
1606 | * by the mid-level itself don't need to call this, but there | |
1607 | * should be no harm. | |
1608 | * | |
1609 | * The main purpose of this is to make sure that a CHECK_CONDITION | |
1610 | * is properly treated. | |
1611 | */ | |
1612 | void scsi_report_bus_reset(struct Scsi_Host *shost, int channel) | |
1613 | { | |
1614 | struct scsi_device *sdev; | |
1615 | ||
1616 | __shost_for_each_device(sdev, shost) { | |
422c0d61 | 1617 | if (channel == sdev_channel(sdev)) { |
1da177e4 LT |
1618 | sdev->was_reset = 1; |
1619 | sdev->expecting_cc_ua = 1; | |
1620 | } | |
1621 | } | |
1622 | } | |
1623 | EXPORT_SYMBOL(scsi_report_bus_reset); | |
1624 | ||
1625 | /* | |
1626 | * Function: scsi_report_device_reset() | |
1627 | * | |
1628 | * Purpose: Utility function used by low-level drivers to report that | |
1629 | * they have observed a device reset on the device being handled. | |
1630 | * | |
1631 | * Arguments: shost - Host in question | |
1632 | * channel - channel on which reset was observed | |
1633 | * target - target on which reset was observed | |
1634 | * | |
1635 | * Returns: Nothing | |
1636 | * | |
1637 | * Lock status: Host lock must be held | |
1638 | * | |
1639 | * Notes: This only needs to be called if the reset is one which | |
1640 | * originates from an unknown location. Resets originated | |
1641 | * by the mid-level itself don't need to call this, but there | |
1642 | * should be no harm. | |
1643 | * | |
1644 | * The main purpose of this is to make sure that a CHECK_CONDITION | |
1645 | * is properly treated. | |
1646 | */ | |
1647 | void scsi_report_device_reset(struct Scsi_Host *shost, int channel, int target) | |
1648 | { | |
1649 | struct scsi_device *sdev; | |
1650 | ||
1651 | __shost_for_each_device(sdev, shost) { | |
422c0d61 JG |
1652 | if (channel == sdev_channel(sdev) && |
1653 | target == sdev_id(sdev)) { | |
1da177e4 LT |
1654 | sdev->was_reset = 1; |
1655 | sdev->expecting_cc_ua = 1; | |
1656 | } | |
1657 | } | |
1658 | } | |
1659 | EXPORT_SYMBOL(scsi_report_device_reset); | |
1660 | ||
1661 | static void | |
1662 | scsi_reset_provider_done_command(struct scsi_cmnd *scmd) | |
1663 | { | |
1664 | } | |
1665 | ||
1666 | /* | |
1667 | * Function: scsi_reset_provider | |
1668 | * | |
1669 | * Purpose: Send requested reset to a bus or device at any phase. | |
1670 | * | |
1671 | * Arguments: device - device to send reset to | |
1672 | * flag - reset type (see scsi.h) | |
1673 | * | |
1674 | * Returns: SUCCESS/FAILURE. | |
1675 | * | |
1676 | * Notes: This is used by the SCSI Generic driver to provide | |
1677 | * Bus/Device reset capability. | |
1678 | */ | |
1679 | int | |
1680 | scsi_reset_provider(struct scsi_device *dev, int flag) | |
1681 | { | |
1682 | struct scsi_cmnd *scmd = scsi_get_command(dev, GFP_KERNEL); | |
d7a1bb0a | 1683 | struct Scsi_Host *shost = dev->host; |
1da177e4 | 1684 | struct request req; |
d7a1bb0a | 1685 | unsigned long flags; |
1da177e4 LT |
1686 | int rtn; |
1687 | ||
1688 | scmd->request = &req; | |
1689 | memset(&scmd->eh_timeout, 0, sizeof(scmd->eh_timeout)); | |
b4edcbca | 1690 | |
1da177e4 LT |
1691 | memset(&scmd->cmnd, '\0', sizeof(scmd->cmnd)); |
1692 | ||
1693 | scmd->scsi_done = scsi_reset_provider_done_command; | |
1694 | scmd->done = NULL; | |
1da177e4 LT |
1695 | scmd->request_buffer = NULL; |
1696 | scmd->request_bufflen = 0; | |
1da177e4 LT |
1697 | |
1698 | scmd->cmd_len = 0; | |
1699 | ||
1700 | scmd->sc_data_direction = DMA_BIDIRECTIONAL; | |
1da177e4 LT |
1701 | |
1702 | init_timer(&scmd->eh_timeout); | |
1703 | ||
1704 | /* | |
1705 | * Sometimes the command can get back into the timer chain, | |
1706 | * so use the pid as an identifier. | |
1707 | */ | |
1708 | scmd->pid = 0; | |
1709 | ||
d7a1bb0a JS |
1710 | spin_lock_irqsave(shost->host_lock, flags); |
1711 | shost->tmf_in_progress = 1; | |
1712 | spin_unlock_irqrestore(shost->host_lock, flags); | |
1713 | ||
1da177e4 LT |
1714 | switch (flag) { |
1715 | case SCSI_TRY_RESET_DEVICE: | |
1716 | rtn = scsi_try_bus_device_reset(scmd); | |
1717 | if (rtn == SUCCESS) | |
1718 | break; | |
1719 | /* FALLTHROUGH */ | |
1720 | case SCSI_TRY_RESET_BUS: | |
1721 | rtn = scsi_try_bus_reset(scmd); | |
1722 | if (rtn == SUCCESS) | |
1723 | break; | |
1724 | /* FALLTHROUGH */ | |
1725 | case SCSI_TRY_RESET_HOST: | |
1726 | rtn = scsi_try_host_reset(scmd); | |
1727 | break; | |
1728 | default: | |
1729 | rtn = FAILED; | |
1730 | } | |
1731 | ||
d7a1bb0a JS |
1732 | spin_lock_irqsave(shost->host_lock, flags); |
1733 | shost->tmf_in_progress = 0; | |
1734 | spin_unlock_irqrestore(shost->host_lock, flags); | |
1735 | ||
1736 | /* | |
1737 | * be sure to wake up anyone who was sleeping or had their queue | |
1738 | * suspended while we performed the TMF. | |
1739 | */ | |
1740 | SCSI_LOG_ERROR_RECOVERY(3, | |
1741 | printk("%s: waking up host to restart after TMF\n", | |
1742 | __FUNCTION__)); | |
1743 | ||
1744 | wake_up(&shost->host_wait); | |
1745 | ||
1746 | scsi_run_host_queues(shost); | |
1747 | ||
1da177e4 LT |
1748 | scsi_next_command(scmd); |
1749 | return rtn; | |
1750 | } | |
1751 | EXPORT_SYMBOL(scsi_reset_provider); | |
1752 | ||
1753 | /** | |
1754 | * scsi_normalize_sense - normalize main elements from either fixed or | |
1755 | * descriptor sense data format into a common format. | |
1756 | * | |
1757 | * @sense_buffer: byte array containing sense data returned by device | |
1758 | * @sb_len: number of valid bytes in sense_buffer | |
1759 | * @sshdr: pointer to instance of structure that common | |
1760 | * elements are written to. | |
1761 | * | |
1762 | * Notes: | |
1763 | * The "main elements" from sense data are: response_code, sense_key, | |
1764 | * asc, ascq and additional_length (only for descriptor format). | |
1765 | * | |
1766 | * Typically this function can be called after a device has | |
1767 | * responded to a SCSI command with the CHECK_CONDITION status. | |
1768 | * | |
1769 | * Return value: | |
1770 | * 1 if valid sense data information found, else 0; | |
1771 | **/ | |
1772 | int scsi_normalize_sense(const u8 *sense_buffer, int sb_len, | |
1773 | struct scsi_sense_hdr *sshdr) | |
1774 | { | |
33aa687d | 1775 | if (!sense_buffer || !sb_len) |
1da177e4 LT |
1776 | return 0; |
1777 | ||
1778 | memset(sshdr, 0, sizeof(struct scsi_sense_hdr)); | |
1779 | ||
1780 | sshdr->response_code = (sense_buffer[0] & 0x7f); | |
33aa687d JB |
1781 | |
1782 | if (!scsi_sense_valid(sshdr)) | |
1783 | return 0; | |
1784 | ||
1da177e4 LT |
1785 | if (sshdr->response_code >= 0x72) { |
1786 | /* | |
1787 | * descriptor format | |
1788 | */ | |
1789 | if (sb_len > 1) | |
1790 | sshdr->sense_key = (sense_buffer[1] & 0xf); | |
1791 | if (sb_len > 2) | |
1792 | sshdr->asc = sense_buffer[2]; | |
1793 | if (sb_len > 3) | |
1794 | sshdr->ascq = sense_buffer[3]; | |
1795 | if (sb_len > 7) | |
1796 | sshdr->additional_length = sense_buffer[7]; | |
1797 | } else { | |
1798 | /* | |
1799 | * fixed format | |
1800 | */ | |
1801 | if (sb_len > 2) | |
1802 | sshdr->sense_key = (sense_buffer[2] & 0xf); | |
1803 | if (sb_len > 7) { | |
1804 | sb_len = (sb_len < (sense_buffer[7] + 8)) ? | |
1805 | sb_len : (sense_buffer[7] + 8); | |
1806 | if (sb_len > 12) | |
1807 | sshdr->asc = sense_buffer[12]; | |
1808 | if (sb_len > 13) | |
1809 | sshdr->ascq = sense_buffer[13]; | |
1810 | } | |
1811 | } | |
1812 | ||
1813 | return 1; | |
1814 | } | |
1815 | EXPORT_SYMBOL(scsi_normalize_sense); | |
1816 | ||
1da177e4 LT |
1817 | int scsi_command_normalize_sense(struct scsi_cmnd *cmd, |
1818 | struct scsi_sense_hdr *sshdr) | |
1819 | { | |
1820 | return scsi_normalize_sense(cmd->sense_buffer, | |
1821 | sizeof(cmd->sense_buffer), sshdr); | |
1822 | } | |
1823 | EXPORT_SYMBOL(scsi_command_normalize_sense); | |
1824 | ||
1825 | /** | |
1826 | * scsi_sense_desc_find - search for a given descriptor type in | |
1827 | * descriptor sense data format. | |
1828 | * | |
1829 | * @sense_buffer: byte array of descriptor format sense data | |
1830 | * @sb_len: number of valid bytes in sense_buffer | |
1831 | * @desc_type: value of descriptor type to find | |
1832 | * (e.g. 0 -> information) | |
1833 | * | |
1834 | * Notes: | |
1835 | * only valid when sense data is in descriptor format | |
1836 | * | |
1837 | * Return value: | |
1838 | * pointer to start of (first) descriptor if found else NULL | |
1839 | **/ | |
1840 | const u8 * scsi_sense_desc_find(const u8 * sense_buffer, int sb_len, | |
1841 | int desc_type) | |
1842 | { | |
1843 | int add_sen_len, add_len, desc_len, k; | |
1844 | const u8 * descp; | |
1845 | ||
1846 | if ((sb_len < 8) || (0 == (add_sen_len = sense_buffer[7]))) | |
1847 | return NULL; | |
1848 | if ((sense_buffer[0] < 0x72) || (sense_buffer[0] > 0x73)) | |
1849 | return NULL; | |
1850 | add_sen_len = (add_sen_len < (sb_len - 8)) ? | |
1851 | add_sen_len : (sb_len - 8); | |
1852 | descp = &sense_buffer[8]; | |
1853 | for (desc_len = 0, k = 0; k < add_sen_len; k += desc_len) { | |
1854 | descp += desc_len; | |
1855 | add_len = (k < (add_sen_len - 1)) ? descp[1]: -1; | |
1856 | desc_len = add_len + 2; | |
1857 | if (descp[0] == desc_type) | |
1858 | return descp; | |
1859 | if (add_len < 0) // short descriptor ?? | |
1860 | break; | |
1861 | } | |
1862 | return NULL; | |
1863 | } | |
1864 | EXPORT_SYMBOL(scsi_sense_desc_find); | |
1865 | ||
1866 | /** | |
1867 | * scsi_get_sense_info_fld - attempts to get information field from | |
1868 | * sense data (either fixed or descriptor format) | |
1869 | * | |
1870 | * @sense_buffer: byte array of sense data | |
1871 | * @sb_len: number of valid bytes in sense_buffer | |
1872 | * @info_out: pointer to 64 integer where 8 or 4 byte information | |
1873 | * field will be placed if found. | |
1874 | * | |
1875 | * Return value: | |
1876 | * 1 if information field found, 0 if not found. | |
1877 | **/ | |
1878 | int scsi_get_sense_info_fld(const u8 * sense_buffer, int sb_len, | |
1879 | u64 * info_out) | |
1880 | { | |
1881 | int j; | |
1882 | const u8 * ucp; | |
1883 | u64 ull; | |
1884 | ||
1885 | if (sb_len < 7) | |
1886 | return 0; | |
1887 | switch (sense_buffer[0] & 0x7f) { | |
1888 | case 0x70: | |
1889 | case 0x71: | |
1890 | if (sense_buffer[0] & 0x80) { | |
1891 | *info_out = (sense_buffer[3] << 24) + | |
1892 | (sense_buffer[4] << 16) + | |
1893 | (sense_buffer[5] << 8) + sense_buffer[6]; | |
1894 | return 1; | |
1895 | } else | |
1896 | return 0; | |
1897 | case 0x72: | |
1898 | case 0x73: | |
1899 | ucp = scsi_sense_desc_find(sense_buffer, sb_len, | |
1900 | 0 /* info desc */); | |
1901 | if (ucp && (0xa == ucp[1])) { | |
1902 | ull = 0; | |
1903 | for (j = 0; j < 8; ++j) { | |
1904 | if (j > 0) | |
1905 | ull <<= 8; | |
1906 | ull |= ucp[4 + j]; | |
1907 | } | |
1908 | *info_out = ull; | |
1909 | return 1; | |
1910 | } else | |
1911 | return 0; | |
1912 | default: | |
1913 | return 0; | |
1914 | } | |
1915 | } | |
1916 | EXPORT_SYMBOL(scsi_get_sense_info_fld); |