Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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> |
| 23 | #include <linux/interrupt.h> |
| 24 | #include <linux/blkdev.h> |
| 25 | #include <linux/delay.h> |
| 26 | |
| 27 | #include <scsi/scsi.h> |
| 28 | #include <scsi/scsi_dbg.h> |
| 29 | #include <scsi/scsi_device.h> |
| 30 | #include <scsi/scsi_eh.h> |
| 31 | #include <scsi/scsi_host.h> |
| 32 | #include <scsi/scsi_ioctl.h> |
| 33 | #include <scsi/scsi_request.h> |
| 34 | |
| 35 | #include "scsi_priv.h" |
| 36 | #include "scsi_logging.h" |
| 37 | |
| 38 | #define SENSE_TIMEOUT (10*HZ) |
| 39 | #define START_UNIT_TIMEOUT (30*HZ) |
| 40 | |
| 41 | /* |
| 42 | * These should *probably* be handled by the host itself. |
| 43 | * Since it is allowed to sleep, it probably should. |
| 44 | */ |
| 45 | #define BUS_RESET_SETTLE_TIME (10) |
| 46 | #define HOST_RESET_SETTLE_TIME (10) |
| 47 | |
| 48 | /* called with shost->host_lock held */ |
| 49 | void scsi_eh_wakeup(struct Scsi_Host *shost) |
| 50 | { |
| 51 | if (shost->host_busy == shost->host_failed) { |
| 52 | up(shost->eh_wait); |
| 53 | SCSI_LOG_ERROR_RECOVERY(5, |
| 54 | printk("Waking error handler thread\n")); |
| 55 | } |
| 56 | } |
| 57 | |
| 58 | /** |
| 59 | * scsi_eh_scmd_add - add scsi cmd to error handling. |
| 60 | * @scmd: scmd to run eh on. |
| 61 | * @eh_flag: optional SCSI_EH flag. |
| 62 | * |
| 63 | * Return value: |
| 64 | * 0 on failure. |
| 65 | **/ |
| 66 | int scsi_eh_scmd_add(struct scsi_cmnd *scmd, int eh_flag) |
| 67 | { |
| 68 | struct Scsi_Host *shost = scmd->device->host; |
| 69 | unsigned long flags; |
| 70 | |
| 71 | if (shost->eh_wait == NULL) |
| 72 | return 0; |
| 73 | |
| 74 | spin_lock_irqsave(shost->host_lock, flags); |
| 75 | |
Christoph Hellwig | 3111b0d | 2005-06-19 13:43:26 +0200 | [diff] [blame] | 76 | scmd->eh_eflags |= eh_flag; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 77 | list_add_tail(&scmd->eh_entry, &shost->eh_cmd_q); |
Mike Anderson | d330187 | 2005-06-16 11:12:38 -0700 | [diff] [blame^] | 78 | scsi_host_set_state(shost, SHOST_RECOVERY); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 79 | shost->host_failed++; |
| 80 | scsi_eh_wakeup(shost); |
| 81 | spin_unlock_irqrestore(shost->host_lock, flags); |
| 82 | return 1; |
| 83 | } |
| 84 | |
| 85 | /** |
| 86 | * scsi_add_timer - Start timeout timer for a single scsi command. |
| 87 | * @scmd: scsi command that is about to start running. |
| 88 | * @timeout: amount of time to allow this command to run. |
| 89 | * @complete: timeout function to call if timer isn't canceled. |
| 90 | * |
| 91 | * Notes: |
| 92 | * This should be turned into an inline function. Each scsi command |
| 93 | * has its own timer, and as it is added to the queue, we set up the |
| 94 | * timer. When the command completes, we cancel the timer. |
| 95 | **/ |
| 96 | void scsi_add_timer(struct scsi_cmnd *scmd, int timeout, |
| 97 | void (*complete)(struct scsi_cmnd *)) |
| 98 | { |
| 99 | |
| 100 | /* |
| 101 | * If the clock was already running for this command, then |
| 102 | * first delete the timer. The timer handling code gets rather |
| 103 | * confused if we don't do this. |
| 104 | */ |
| 105 | if (scmd->eh_timeout.function) |
| 106 | del_timer(&scmd->eh_timeout); |
| 107 | |
| 108 | scmd->eh_timeout.data = (unsigned long)scmd; |
| 109 | scmd->eh_timeout.expires = jiffies + timeout; |
| 110 | scmd->eh_timeout.function = (void (*)(unsigned long)) complete; |
| 111 | |
| 112 | SCSI_LOG_ERROR_RECOVERY(5, printk("%s: scmd: %p, time:" |
| 113 | " %d, (%p)\n", __FUNCTION__, |
| 114 | scmd, timeout, complete)); |
| 115 | |
| 116 | add_timer(&scmd->eh_timeout); |
| 117 | } |
| 118 | EXPORT_SYMBOL(scsi_add_timer); |
| 119 | |
| 120 | /** |
| 121 | * scsi_delete_timer - Delete/cancel timer for a given function. |
| 122 | * @scmd: Cmd that we are canceling timer for |
| 123 | * |
| 124 | * Notes: |
| 125 | * This should be turned into an inline function. |
| 126 | * |
| 127 | * Return value: |
| 128 | * 1 if we were able to detach the timer. 0 if we blew it, and the |
| 129 | * timer function has already started to run. |
| 130 | **/ |
| 131 | int scsi_delete_timer(struct scsi_cmnd *scmd) |
| 132 | { |
| 133 | int rtn; |
| 134 | |
| 135 | rtn = del_timer(&scmd->eh_timeout); |
| 136 | |
| 137 | SCSI_LOG_ERROR_RECOVERY(5, printk("%s: scmd: %p," |
| 138 | " rtn: %d\n", __FUNCTION__, |
| 139 | scmd, rtn)); |
| 140 | |
| 141 | scmd->eh_timeout.data = (unsigned long)NULL; |
| 142 | scmd->eh_timeout.function = NULL; |
| 143 | |
| 144 | return rtn; |
| 145 | } |
| 146 | EXPORT_SYMBOL(scsi_delete_timer); |
| 147 | |
| 148 | /** |
| 149 | * scsi_times_out - Timeout function for normal scsi commands. |
| 150 | * @scmd: Cmd that is timing out. |
| 151 | * |
| 152 | * Notes: |
| 153 | * We do not need to lock this. There is the potential for a race |
| 154 | * only in that the normal completion handling might run, but if the |
| 155 | * normal completion function determines that the timer has already |
| 156 | * fired, then it mustn't do anything. |
| 157 | **/ |
| 158 | void scsi_times_out(struct scsi_cmnd *scmd) |
| 159 | { |
| 160 | scsi_log_completion(scmd, TIMEOUT_ERROR); |
| 161 | |
| 162 | if (scmd->device->host->hostt->eh_timed_out) |
| 163 | switch (scmd->device->host->hostt->eh_timed_out(scmd)) { |
| 164 | case EH_HANDLED: |
| 165 | __scsi_done(scmd); |
| 166 | return; |
| 167 | case EH_RESET_TIMER: |
| 168 | /* This allows a single retry even of a command |
| 169 | * with allowed == 0 */ |
| 170 | if (scmd->retries++ > scmd->allowed) |
| 171 | break; |
| 172 | scsi_add_timer(scmd, scmd->timeout_per_command, |
| 173 | scsi_times_out); |
| 174 | return; |
| 175 | case EH_NOT_HANDLED: |
| 176 | break; |
| 177 | } |
| 178 | |
| 179 | if (unlikely(!scsi_eh_scmd_add(scmd, SCSI_EH_CANCEL_CMD))) { |
| 180 | panic("Error handler thread not present at %p %p %s %d", |
| 181 | scmd, scmd->device->host, __FILE__, __LINE__); |
| 182 | } |
| 183 | } |
| 184 | |
| 185 | /** |
| 186 | * scsi_block_when_processing_errors - Prevent cmds from being queued. |
| 187 | * @sdev: Device on which we are performing recovery. |
| 188 | * |
| 189 | * Description: |
| 190 | * We block until the host is out of error recovery, and then check to |
| 191 | * see whether the host or the device is offline. |
| 192 | * |
| 193 | * Return value: |
| 194 | * 0 when dev was taken offline by error recovery. 1 OK to proceed. |
| 195 | **/ |
| 196 | int scsi_block_when_processing_errors(struct scsi_device *sdev) |
| 197 | { |
| 198 | int online; |
| 199 | |
Mike Anderson | d330187 | 2005-06-16 11:12:38 -0700 | [diff] [blame^] | 200 | wait_event(sdev->host->host_wait, (sdev->host->shost_state != |
| 201 | SHOST_RECOVERY)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 202 | |
| 203 | online = scsi_device_online(sdev); |
| 204 | |
| 205 | SCSI_LOG_ERROR_RECOVERY(5, printk("%s: rtn: %d\n", __FUNCTION__, |
| 206 | online)); |
| 207 | |
| 208 | return online; |
| 209 | } |
| 210 | EXPORT_SYMBOL(scsi_block_when_processing_errors); |
| 211 | |
| 212 | #ifdef CONFIG_SCSI_LOGGING |
| 213 | /** |
| 214 | * scsi_eh_prt_fail_stats - Log info on failures. |
| 215 | * @shost: scsi host being recovered. |
| 216 | * @work_q: Queue of scsi cmds to process. |
| 217 | **/ |
| 218 | static inline void scsi_eh_prt_fail_stats(struct Scsi_Host *shost, |
| 219 | struct list_head *work_q) |
| 220 | { |
| 221 | struct scsi_cmnd *scmd; |
| 222 | struct scsi_device *sdev; |
| 223 | int total_failures = 0; |
| 224 | int cmd_failed = 0; |
| 225 | int cmd_cancel = 0; |
| 226 | int devices_failed = 0; |
| 227 | |
| 228 | shost_for_each_device(sdev, shost) { |
| 229 | list_for_each_entry(scmd, work_q, eh_entry) { |
| 230 | if (scmd->device == sdev) { |
| 231 | ++total_failures; |
Christoph Hellwig | 3111b0d | 2005-06-19 13:43:26 +0200 | [diff] [blame] | 232 | if (scmd->eh_eflags & SCSI_EH_CANCEL_CMD) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 233 | ++cmd_cancel; |
| 234 | else |
| 235 | ++cmd_failed; |
| 236 | } |
| 237 | } |
| 238 | |
| 239 | if (cmd_cancel || cmd_failed) { |
| 240 | SCSI_LOG_ERROR_RECOVERY(3, |
| 241 | printk("%s: %d:%d:%d:%d cmds failed: %d," |
| 242 | " cancel: %d\n", |
| 243 | __FUNCTION__, shost->host_no, |
| 244 | sdev->channel, sdev->id, sdev->lun, |
| 245 | cmd_failed, cmd_cancel)); |
| 246 | cmd_cancel = 0; |
| 247 | cmd_failed = 0; |
| 248 | ++devices_failed; |
| 249 | } |
| 250 | } |
| 251 | |
| 252 | SCSI_LOG_ERROR_RECOVERY(2, printk("Total of %d commands on %d" |
| 253 | " devices require eh work\n", |
| 254 | total_failures, devices_failed)); |
| 255 | } |
| 256 | #endif |
| 257 | |
| 258 | /** |
| 259 | * scsi_check_sense - Examine scsi cmd sense |
| 260 | * @scmd: Cmd to have sense checked. |
| 261 | * |
| 262 | * Return value: |
| 263 | * SUCCESS or FAILED or NEEDS_RETRY |
| 264 | * |
| 265 | * Notes: |
| 266 | * When a deferred error is detected the current command has |
| 267 | * not been executed and needs retrying. |
| 268 | **/ |
| 269 | static int scsi_check_sense(struct scsi_cmnd *scmd) |
| 270 | { |
| 271 | struct scsi_sense_hdr sshdr; |
| 272 | |
| 273 | if (! scsi_command_normalize_sense(scmd, &sshdr)) |
| 274 | return FAILED; /* no valid sense data */ |
| 275 | |
| 276 | if (scsi_sense_is_deferred(&sshdr)) |
| 277 | return NEEDS_RETRY; |
| 278 | |
| 279 | /* |
| 280 | * Previous logic looked for FILEMARK, EOM or ILI which are |
| 281 | * mainly associated with tapes and returned SUCCESS. |
| 282 | */ |
| 283 | if (sshdr.response_code == 0x70) { |
| 284 | /* fixed format */ |
| 285 | if (scmd->sense_buffer[2] & 0xe0) |
| 286 | return SUCCESS; |
| 287 | } else { |
| 288 | /* |
| 289 | * descriptor format: look for "stream commands sense data |
| 290 | * descriptor" (see SSC-3). Assume single sense data |
| 291 | * descriptor. Ignore ILI from SBC-2 READ LONG and WRITE LONG. |
| 292 | */ |
| 293 | if ((sshdr.additional_length > 3) && |
| 294 | (scmd->sense_buffer[8] == 0x4) && |
| 295 | (scmd->sense_buffer[11] & 0xe0)) |
| 296 | return SUCCESS; |
| 297 | } |
| 298 | |
| 299 | switch (sshdr.sense_key) { |
| 300 | case NO_SENSE: |
| 301 | return SUCCESS; |
| 302 | case RECOVERED_ERROR: |
| 303 | return /* soft_error */ SUCCESS; |
| 304 | |
| 305 | case ABORTED_COMMAND: |
| 306 | return NEEDS_RETRY; |
| 307 | case NOT_READY: |
| 308 | case UNIT_ATTENTION: |
| 309 | /* |
| 310 | * if we are expecting a cc/ua because of a bus reset that we |
| 311 | * performed, treat this just as a retry. otherwise this is |
| 312 | * information that we should pass up to the upper-level driver |
| 313 | * so that we can deal with it there. |
| 314 | */ |
| 315 | if (scmd->device->expecting_cc_ua) { |
| 316 | scmd->device->expecting_cc_ua = 0; |
| 317 | return NEEDS_RETRY; |
| 318 | } |
| 319 | /* |
| 320 | * if the device is in the process of becoming ready, we |
| 321 | * should retry. |
| 322 | */ |
| 323 | if ((sshdr.asc == 0x04) && (sshdr.ascq == 0x01)) |
| 324 | return NEEDS_RETRY; |
| 325 | /* |
| 326 | * if the device is not started, we need to wake |
| 327 | * the error handler to start the motor |
| 328 | */ |
| 329 | if (scmd->device->allow_restart && |
| 330 | (sshdr.asc == 0x04) && (sshdr.ascq == 0x02)) |
| 331 | return FAILED; |
| 332 | return SUCCESS; |
| 333 | |
| 334 | /* these three are not supported */ |
| 335 | case COPY_ABORTED: |
| 336 | case VOLUME_OVERFLOW: |
| 337 | case MISCOMPARE: |
| 338 | return SUCCESS; |
| 339 | |
| 340 | case MEDIUM_ERROR: |
| 341 | return NEEDS_RETRY; |
| 342 | |
| 343 | case HARDWARE_ERROR: |
| 344 | if (scmd->device->retry_hwerror) |
| 345 | return NEEDS_RETRY; |
| 346 | else |
| 347 | return SUCCESS; |
| 348 | |
| 349 | case ILLEGAL_REQUEST: |
| 350 | case BLANK_CHECK: |
| 351 | case DATA_PROTECT: |
| 352 | default: |
| 353 | return SUCCESS; |
| 354 | } |
| 355 | } |
| 356 | |
| 357 | /** |
| 358 | * scsi_eh_completed_normally - Disposition a eh cmd on return from LLD. |
| 359 | * @scmd: SCSI cmd to examine. |
| 360 | * |
| 361 | * Notes: |
| 362 | * This is *only* called when we are examining the status of commands |
| 363 | * queued during error recovery. the main difference here is that we |
| 364 | * don't allow for the possibility of retries here, and we are a lot |
| 365 | * more restrictive about what we consider acceptable. |
| 366 | **/ |
| 367 | static int scsi_eh_completed_normally(struct scsi_cmnd *scmd) |
| 368 | { |
| 369 | /* |
| 370 | * first check the host byte, to see if there is anything in there |
| 371 | * that would indicate what we need to do. |
| 372 | */ |
| 373 | if (host_byte(scmd->result) == DID_RESET) { |
| 374 | /* |
| 375 | * rats. we are already in the error handler, so we now |
| 376 | * get to try and figure out what to do next. if the sense |
| 377 | * is valid, we have a pretty good idea of what to do. |
| 378 | * if not, we mark it as FAILED. |
| 379 | */ |
| 380 | return scsi_check_sense(scmd); |
| 381 | } |
| 382 | if (host_byte(scmd->result) != DID_OK) |
| 383 | return FAILED; |
| 384 | |
| 385 | /* |
| 386 | * next, check the message byte. |
| 387 | */ |
| 388 | if (msg_byte(scmd->result) != COMMAND_COMPLETE) |
| 389 | return FAILED; |
| 390 | |
| 391 | /* |
| 392 | * now, check the status byte to see if this indicates |
| 393 | * anything special. |
| 394 | */ |
| 395 | switch (status_byte(scmd->result)) { |
| 396 | case GOOD: |
| 397 | case COMMAND_TERMINATED: |
| 398 | return SUCCESS; |
| 399 | case CHECK_CONDITION: |
| 400 | return scsi_check_sense(scmd); |
| 401 | case CONDITION_GOOD: |
| 402 | case INTERMEDIATE_GOOD: |
| 403 | case INTERMEDIATE_C_GOOD: |
| 404 | /* |
| 405 | * who knows? FIXME(eric) |
| 406 | */ |
| 407 | return SUCCESS; |
| 408 | case BUSY: |
| 409 | case QUEUE_FULL: |
| 410 | case RESERVATION_CONFLICT: |
| 411 | default: |
| 412 | return FAILED; |
| 413 | } |
| 414 | return FAILED; |
| 415 | } |
| 416 | |
| 417 | /** |
| 418 | * scsi_eh_times_out - timeout function for error handling. |
| 419 | * @scmd: Cmd that is timing out. |
| 420 | * |
| 421 | * Notes: |
| 422 | * During error handling, the kernel thread will be sleeping waiting |
| 423 | * for some action to complete on the device. our only job is to |
| 424 | * record that it timed out, and to wake up the thread. |
| 425 | **/ |
| 426 | static void scsi_eh_times_out(struct scsi_cmnd *scmd) |
| 427 | { |
Christoph Hellwig | 3111b0d | 2005-06-19 13:43:26 +0200 | [diff] [blame] | 428 | scmd->eh_eflags |= SCSI_EH_REC_TIMEOUT; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 429 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: scmd:%p\n", __FUNCTION__, |
| 430 | scmd)); |
| 431 | |
Tejun Heo | 5b8ef84 | 2005-05-14 00:46:18 +0900 | [diff] [blame] | 432 | up(scmd->device->host->eh_action); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 433 | } |
| 434 | |
| 435 | /** |
| 436 | * scsi_eh_done - Completion function for error handling. |
| 437 | * @scmd: Cmd that is done. |
| 438 | **/ |
| 439 | static void scsi_eh_done(struct scsi_cmnd *scmd) |
| 440 | { |
| 441 | /* |
| 442 | * if the timeout handler is already running, then just set the |
| 443 | * flag which says we finished late, and return. we have no |
| 444 | * way of stopping the timeout handler from running, so we must |
| 445 | * always defer to it. |
| 446 | */ |
| 447 | if (del_timer(&scmd->eh_timeout)) { |
| 448 | scmd->request->rq_status = RQ_SCSI_DONE; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 449 | |
| 450 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s scmd: %p result: %x\n", |
| 451 | __FUNCTION__, scmd, scmd->result)); |
| 452 | |
Tejun Heo | 5b8ef84 | 2005-05-14 00:46:18 +0900 | [diff] [blame] | 453 | up(scmd->device->host->eh_action); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 454 | } |
| 455 | } |
| 456 | |
| 457 | /** |
| 458 | * scsi_send_eh_cmnd - send a cmd to a device as part of error recovery. |
| 459 | * @scmd: SCSI Cmd to send. |
| 460 | * @timeout: Timeout for cmd. |
| 461 | * |
| 462 | * Notes: |
| 463 | * The initialization of the structures is quite a bit different in |
| 464 | * this case, and furthermore, there is a different completion handler |
| 465 | * vs scsi_dispatch_cmd. |
| 466 | * Return value: |
| 467 | * SUCCESS or FAILED or NEEDS_RETRY |
| 468 | **/ |
| 469 | static int scsi_send_eh_cmnd(struct scsi_cmnd *scmd, int timeout) |
| 470 | { |
| f59114b | 2005-04-17 15:00:23 -0500 | [diff] [blame] | 471 | struct scsi_device *sdev = scmd->device; |
| 472 | struct Scsi_Host *shost = sdev->host; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 473 | DECLARE_MUTEX_LOCKED(sem); |
| 474 | unsigned long flags; |
| 475 | int rtn = SUCCESS; |
| 476 | |
| 477 | /* |
| 478 | * we will use a queued command if possible, otherwise we will |
| 479 | * emulate the queuing and calling of completion function ourselves. |
| 480 | */ |
| f59114b | 2005-04-17 15:00:23 -0500 | [diff] [blame] | 481 | if (sdev->scsi_level <= SCSI_2) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 482 | scmd->cmnd[1] = (scmd->cmnd[1] & 0x1f) | |
| f59114b | 2005-04-17 15:00:23 -0500 | [diff] [blame] | 483 | (sdev->lun << 5 & 0xe0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 484 | |
| 485 | scsi_add_timer(scmd, timeout, scsi_eh_times_out); |
| 486 | |
| 487 | /* |
| 488 | * set up the semaphore so we wait for the command to complete. |
| 489 | */ |
| f59114b | 2005-04-17 15:00:23 -0500 | [diff] [blame] | 490 | shost->eh_action = &sem; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 491 | scmd->request->rq_status = RQ_SCSI_BUSY; |
| 492 | |
| f59114b | 2005-04-17 15:00:23 -0500 | [diff] [blame] | 493 | spin_lock_irqsave(shost->host_lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 494 | scsi_log_send(scmd); |
| f59114b | 2005-04-17 15:00:23 -0500 | [diff] [blame] | 495 | shost->hostt->queuecommand(scmd, scsi_eh_done); |
| 496 | spin_unlock_irqrestore(shost->host_lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 497 | |
| 498 | down(&sem); |
| 499 | scsi_log_completion(scmd, SUCCESS); |
| 500 | |
| f59114b | 2005-04-17 15:00:23 -0500 | [diff] [blame] | 501 | shost->eh_action = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 502 | |
| 503 | /* |
| 504 | * see if timeout. if so, tell the host to forget about it. |
| 505 | * in other words, we don't want a callback any more. |
| 506 | */ |
Christoph Hellwig | 3111b0d | 2005-06-19 13:43:26 +0200 | [diff] [blame] | 507 | if (scmd->eh_eflags & SCSI_EH_REC_TIMEOUT) { |
| 508 | scmd->eh_eflags &= ~SCSI_EH_REC_TIMEOUT; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 509 | |
| 510 | /* |
| 511 | * as far as the low level driver is |
| 512 | * concerned, this command is still active, so |
| 513 | * we must give the low level driver a chance |
| 514 | * to abort it. (db) |
| 515 | * |
| 516 | * FIXME(eric) - we are not tracking whether we could |
| 517 | * abort a timed out command or not. not sure how |
| 518 | * we should treat them differently anyways. |
| 519 | */ |
| f59114b | 2005-04-17 15:00:23 -0500 | [diff] [blame] | 520 | if (shost->hostt->eh_abort_handler) |
| 521 | shost->hostt->eh_abort_handler(scmd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 522 | |
| 523 | scmd->request->rq_status = RQ_SCSI_DONE; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 524 | rtn = FAILED; |
| 525 | } |
| 526 | |
| 527 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: scmd: %p, rtn:%x\n", |
| 528 | __FUNCTION__, scmd, rtn)); |
| 529 | |
| 530 | /* |
| 531 | * now examine the actual status codes to see whether the command |
| 532 | * actually did complete normally. |
| 533 | */ |
| 534 | if (rtn == SUCCESS) { |
| 535 | rtn = scsi_eh_completed_normally(scmd); |
| 536 | SCSI_LOG_ERROR_RECOVERY(3, |
| 537 | printk("%s: scsi_eh_completed_normally %x\n", |
| 538 | __FUNCTION__, rtn)); |
| 539 | switch (rtn) { |
| 540 | case SUCCESS: |
| 541 | case NEEDS_RETRY: |
| 542 | case FAILED: |
| 543 | break; |
| 544 | default: |
| 545 | rtn = FAILED; |
| 546 | break; |
| 547 | } |
| 548 | } |
| 549 | |
| 550 | return rtn; |
| 551 | } |
| 552 | |
| 553 | /** |
| 554 | * scsi_request_sense - Request sense data from a particular target. |
| 555 | * @scmd: SCSI cmd for request sense. |
| 556 | * |
| 557 | * Notes: |
| 558 | * Some hosts automatically obtain this information, others require |
| 559 | * that we obtain it on our own. This function will *not* return until |
| 560 | * the command either times out, or it completes. |
| 561 | **/ |
| 562 | static int scsi_request_sense(struct scsi_cmnd *scmd) |
| 563 | { |
| 564 | static unsigned char generic_sense[6] = |
| 565 | {REQUEST_SENSE, 0, 0, 0, 252, 0}; |
| 566 | unsigned char *scsi_result; |
| 567 | int saved_result; |
| 568 | int rtn; |
| 569 | |
| 570 | memcpy(scmd->cmnd, generic_sense, sizeof(generic_sense)); |
| 571 | |
Al Viro | bc86120 | 2005-04-24 12:28:34 -0700 | [diff] [blame] | 572 | scsi_result = kmalloc(252, GFP_ATOMIC | ((scmd->device->host->hostt->unchecked_isa_dma) ? __GFP_DMA : 0)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 573 | |
| 574 | |
| 575 | if (unlikely(!scsi_result)) { |
| 576 | printk(KERN_ERR "%s: cannot allocate scsi_result.\n", |
| 577 | __FUNCTION__); |
| 578 | return FAILED; |
| 579 | } |
| 580 | |
| 581 | /* |
| 582 | * zero the sense buffer. some host adapters automatically always |
| 583 | * request sense, so it is not a good idea that |
| 584 | * scmd->request_buffer and scmd->sense_buffer point to the same |
| 585 | * address (db). 0 is not a valid sense code. |
| 586 | */ |
| 587 | memset(scmd->sense_buffer, 0, sizeof(scmd->sense_buffer)); |
| 588 | memset(scsi_result, 0, 252); |
| 589 | |
| 590 | saved_result = scmd->result; |
| 591 | scmd->request_buffer = scsi_result; |
| 592 | scmd->request_bufflen = 252; |
| 593 | scmd->use_sg = 0; |
| 594 | scmd->cmd_len = COMMAND_SIZE(scmd->cmnd[0]); |
| 595 | scmd->sc_data_direction = DMA_FROM_DEVICE; |
| 596 | scmd->underflow = 0; |
| 597 | |
| 598 | rtn = scsi_send_eh_cmnd(scmd, SENSE_TIMEOUT); |
| 599 | |
| 600 | /* last chance to have valid sense data */ |
| 601 | if(!SCSI_SENSE_VALID(scmd)) { |
| 602 | memcpy(scmd->sense_buffer, scmd->request_buffer, |
| 603 | sizeof(scmd->sense_buffer)); |
| 604 | } |
| 605 | |
| 606 | kfree(scsi_result); |
| 607 | |
| 608 | /* |
| 609 | * when we eventually call scsi_finish, we really wish to complete |
| 610 | * the original request, so let's restore the original data. (db) |
| 611 | */ |
| 612 | scsi_setup_cmd_retry(scmd); |
| 613 | scmd->result = saved_result; |
| 614 | return rtn; |
| 615 | } |
| 616 | |
| 617 | /** |
| 618 | * scsi_eh_finish_cmd - Handle a cmd that eh is finished with. |
| 619 | * @scmd: Original SCSI cmd that eh has finished. |
| 620 | * @done_q: Queue for processed commands. |
| 621 | * |
| 622 | * Notes: |
| 623 | * We don't want to use the normal command completion while we are are |
| 624 | * still handling errors - it may cause other commands to be queued, |
| 625 | * and that would disturb what we are doing. thus we really want to |
| 626 | * keep a list of pending commands for final completion, and once we |
| 627 | * are ready to leave error handling we handle completion for real. |
| 628 | **/ |
| 629 | static void scsi_eh_finish_cmd(struct scsi_cmnd *scmd, |
| 630 | struct list_head *done_q) |
| 631 | { |
| 632 | scmd->device->host->host_failed--; |
Christoph Hellwig | 3111b0d | 2005-06-19 13:43:26 +0200 | [diff] [blame] | 633 | scmd->eh_eflags = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 634 | |
| 635 | /* |
| 636 | * set this back so that the upper level can correctly free up |
| 637 | * things. |
| 638 | */ |
| 639 | scsi_setup_cmd_retry(scmd); |
| 640 | list_move_tail(&scmd->eh_entry, done_q); |
| 641 | } |
| 642 | |
| 643 | /** |
| 644 | * scsi_eh_get_sense - Get device sense data. |
| 645 | * @work_q: Queue of commands to process. |
| 646 | * @done_q: Queue of proccessed commands.. |
| 647 | * |
| 648 | * Description: |
| 649 | * See if we need to request sense information. if so, then get it |
| 650 | * now, so we have a better idea of what to do. |
| 651 | * |
| 652 | * Notes: |
| 653 | * This has the unfortunate side effect that if a shost adapter does |
| 654 | * not automatically request sense information, that we end up shutting |
| 655 | * it down before we request it. |
| 656 | * |
| 657 | * All drivers should request sense information internally these days, |
| 658 | * so for now all I have to say is tough noogies if you end up in here. |
| 659 | * |
| 660 | * XXX: Long term this code should go away, but that needs an audit of |
| 661 | * all LLDDs first. |
| 662 | **/ |
| 663 | static int scsi_eh_get_sense(struct list_head *work_q, |
| 664 | struct list_head *done_q) |
| 665 | { |
Christoph Hellwig | 937abeaa | 2005-06-19 13:43:56 +0200 | [diff] [blame] | 666 | struct scsi_cmnd *scmd, *next; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 667 | int rtn; |
| 668 | |
Christoph Hellwig | 937abeaa | 2005-06-19 13:43:56 +0200 | [diff] [blame] | 669 | list_for_each_entry_safe(scmd, next, work_q, eh_entry) { |
Christoph Hellwig | 3111b0d | 2005-06-19 13:43:26 +0200 | [diff] [blame] | 670 | if ((scmd->eh_eflags & SCSI_EH_CANCEL_CMD) || |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 671 | SCSI_SENSE_VALID(scmd)) |
| 672 | continue; |
| 673 | |
| 674 | SCSI_LOG_ERROR_RECOVERY(2, printk("%s: requesting sense" |
| 675 | " for id: %d\n", |
| 676 | current->comm, |
| 677 | scmd->device->id)); |
| 678 | rtn = scsi_request_sense(scmd); |
| 679 | if (rtn != SUCCESS) |
| 680 | continue; |
| 681 | |
| 682 | SCSI_LOG_ERROR_RECOVERY(3, printk("sense requested for %p" |
| 683 | " result %x\n", scmd, |
| 684 | scmd->result)); |
| 685 | SCSI_LOG_ERROR_RECOVERY(3, scsi_print_sense("bh", scmd)); |
| 686 | |
| 687 | rtn = scsi_decide_disposition(scmd); |
| 688 | |
| 689 | /* |
| 690 | * if the result was normal, then just pass it along to the |
| 691 | * upper level. |
| 692 | */ |
| 693 | if (rtn == SUCCESS) |
| 694 | /* we don't want this command reissued, just |
| 695 | * finished with the sense data, so set |
| 696 | * retries to the max allowed to ensure it |
| 697 | * won't get reissued */ |
| 698 | scmd->retries = scmd->allowed; |
| 699 | else if (rtn != NEEDS_RETRY) |
| 700 | continue; |
| 701 | |
| 702 | scsi_eh_finish_cmd(scmd, done_q); |
| 703 | } |
| 704 | |
| 705 | return list_empty(work_q); |
| 706 | } |
| 707 | |
| 708 | /** |
| 709 | * scsi_try_to_abort_cmd - Ask host to abort a running command. |
| 710 | * @scmd: SCSI cmd to abort from Lower Level. |
| 711 | * |
| 712 | * Notes: |
| 713 | * This function will not return until the user's completion function |
| 714 | * has been called. there is no timeout on this operation. if the |
| 715 | * author of the low-level driver wishes this operation to be timed, |
| 716 | * they can provide this facility themselves. helper functions in |
| 717 | * scsi_error.c can be supplied to make this easier to do. |
| 718 | **/ |
| 719 | static int scsi_try_to_abort_cmd(struct scsi_cmnd *scmd) |
| 720 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 721 | if (!scmd->device->host->hostt->eh_abort_handler) |
Jeff Garzik | 8fa728a | 2005-05-28 07:54:40 -0400 | [diff] [blame] | 722 | return FAILED; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 723 | |
| 724 | /* |
| 725 | * scsi_done was called just after the command timed out and before |
| 726 | * we had a chance to process it. (db) |
| 727 | */ |
| 728 | if (scmd->serial_number == 0) |
| 729 | return SUCCESS; |
Jeff Garzik | 8fa728a | 2005-05-28 07:54:40 -0400 | [diff] [blame] | 730 | return scmd->device->host->hostt->eh_abort_handler(scmd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 731 | } |
| 732 | |
| 733 | /** |
| 734 | * scsi_eh_tur - Send TUR to device. |
| 735 | * @scmd: Scsi cmd to send TUR |
| 736 | * |
| 737 | * Return value: |
| 738 | * 0 - Device is ready. 1 - Device NOT ready. |
| 739 | **/ |
| 740 | static int scsi_eh_tur(struct scsi_cmnd *scmd) |
| 741 | { |
| 742 | static unsigned char tur_command[6] = {TEST_UNIT_READY, 0, 0, 0, 0, 0}; |
| 743 | int retry_cnt = 1, rtn; |
Patrick Mansfield | 793698c | 2005-05-16 17:42:15 -0700 | [diff] [blame] | 744 | int saved_result; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 745 | |
| 746 | retry_tur: |
| 747 | memcpy(scmd->cmnd, tur_command, sizeof(tur_command)); |
| 748 | |
| 749 | /* |
| 750 | * zero the sense buffer. the scsi spec mandates that any |
| 751 | * untransferred sense data should be interpreted as being zero. |
| 752 | */ |
| 753 | memset(scmd->sense_buffer, 0, sizeof(scmd->sense_buffer)); |
| 754 | |
Patrick Mansfield | 793698c | 2005-05-16 17:42:15 -0700 | [diff] [blame] | 755 | saved_result = scmd->result; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 756 | scmd->request_buffer = NULL; |
| 757 | scmd->request_bufflen = 0; |
| 758 | scmd->use_sg = 0; |
| 759 | scmd->cmd_len = COMMAND_SIZE(scmd->cmnd[0]); |
| 760 | scmd->underflow = 0; |
| 761 | scmd->sc_data_direction = DMA_NONE; |
| 762 | |
| 763 | rtn = scsi_send_eh_cmnd(scmd, SENSE_TIMEOUT); |
| 764 | |
| 765 | /* |
| 766 | * when we eventually call scsi_finish, we really wish to complete |
| 767 | * the original request, so let's restore the original data. (db) |
| 768 | */ |
| 769 | scsi_setup_cmd_retry(scmd); |
Patrick Mansfield | 793698c | 2005-05-16 17:42:15 -0700 | [diff] [blame] | 770 | scmd->result = saved_result; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 771 | |
| 772 | /* |
| 773 | * hey, we are done. let's look to see what happened. |
| 774 | */ |
| 775 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: scmd %p rtn %x\n", |
| 776 | __FUNCTION__, scmd, rtn)); |
| 777 | if (rtn == SUCCESS) |
| 778 | return 0; |
| 779 | else if (rtn == NEEDS_RETRY) |
| 780 | if (retry_cnt--) |
| 781 | goto retry_tur; |
| 782 | return 1; |
| 783 | } |
| 784 | |
| 785 | /** |
| 786 | * scsi_eh_abort_cmds - abort canceled commands. |
| 787 | * @shost: scsi host being recovered. |
| 788 | * @eh_done_q: list_head for processed commands. |
| 789 | * |
| 790 | * Decription: |
| 791 | * Try and see whether or not it makes sense to try and abort the |
| 792 | * running command. this only works out to be the case if we have one |
| 793 | * command that has timed out. if the command simply failed, it makes |
| 794 | * no sense to try and abort the command, since as far as the shost |
| 795 | * adapter is concerned, it isn't running. |
| 796 | **/ |
| 797 | static int scsi_eh_abort_cmds(struct list_head *work_q, |
| 798 | struct list_head *done_q) |
| 799 | { |
Christoph Hellwig | 937abeaa | 2005-06-19 13:43:56 +0200 | [diff] [blame] | 800 | struct scsi_cmnd *scmd, *next; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 801 | int rtn; |
| 802 | |
Christoph Hellwig | 937abeaa | 2005-06-19 13:43:56 +0200 | [diff] [blame] | 803 | list_for_each_entry_safe(scmd, next, work_q, eh_entry) { |
Christoph Hellwig | 3111b0d | 2005-06-19 13:43:26 +0200 | [diff] [blame] | 804 | if (!(scmd->eh_eflags & SCSI_EH_CANCEL_CMD)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 805 | continue; |
| 806 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: aborting cmd:" |
| 807 | "0x%p\n", current->comm, |
| 808 | scmd)); |
| 809 | rtn = scsi_try_to_abort_cmd(scmd); |
| 810 | if (rtn == SUCCESS) { |
Christoph Hellwig | 3111b0d | 2005-06-19 13:43:26 +0200 | [diff] [blame] | 811 | scmd->eh_eflags &= ~SCSI_EH_CANCEL_CMD; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 812 | if (!scsi_device_online(scmd->device) || |
| 813 | !scsi_eh_tur(scmd)) { |
| 814 | scsi_eh_finish_cmd(scmd, done_q); |
| 815 | } |
| 816 | |
| 817 | } else |
| 818 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: aborting" |
| 819 | " cmd failed:" |
| 820 | "0x%p\n", |
| 821 | current->comm, |
| 822 | scmd)); |
| 823 | } |
| 824 | |
| 825 | return list_empty(work_q); |
| 826 | } |
| 827 | |
| 828 | /** |
| 829 | * scsi_try_bus_device_reset - Ask host to perform a BDR on a dev |
| 830 | * @scmd: SCSI cmd used to send BDR |
| 831 | * |
| 832 | * Notes: |
| 833 | * There is no timeout for this operation. if this operation is |
| 834 | * unreliable for a given host, then the host itself needs to put a |
| 835 | * timer on it, and set the host back to a consistent state prior to |
| 836 | * returning. |
| 837 | **/ |
| 838 | static int scsi_try_bus_device_reset(struct scsi_cmnd *scmd) |
| 839 | { |
Jeff Garzik | 94d0e7b8 | 2005-05-28 07:55:48 -0400 | [diff] [blame] | 840 | int rtn; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 841 | |
| 842 | if (!scmd->device->host->hostt->eh_device_reset_handler) |
Jeff Garzik | 94d0e7b8 | 2005-05-28 07:55:48 -0400 | [diff] [blame] | 843 | return FAILED; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 844 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 845 | rtn = scmd->device->host->hostt->eh_device_reset_handler(scmd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 846 | if (rtn == SUCCESS) { |
| 847 | scmd->device->was_reset = 1; |
| 848 | scmd->device->expecting_cc_ua = 1; |
| 849 | } |
| 850 | |
| 851 | return rtn; |
| 852 | } |
| 853 | |
| 854 | /** |
| 855 | * scsi_eh_try_stu - Send START_UNIT to device. |
| 856 | * @scmd: Scsi cmd to send START_UNIT |
| 857 | * |
| 858 | * Return value: |
| 859 | * 0 - Device is ready. 1 - Device NOT ready. |
| 860 | **/ |
| 861 | static int scsi_eh_try_stu(struct scsi_cmnd *scmd) |
| 862 | { |
| 863 | static unsigned char stu_command[6] = {START_STOP, 0, 0, 0, 1, 0}; |
| 864 | int rtn; |
Patrick Mansfield | 793698c | 2005-05-16 17:42:15 -0700 | [diff] [blame] | 865 | int saved_result; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 866 | |
| 867 | if (!scmd->device->allow_restart) |
| 868 | return 1; |
| 869 | |
| 870 | memcpy(scmd->cmnd, stu_command, sizeof(stu_command)); |
| 871 | |
| 872 | /* |
| 873 | * zero the sense buffer. the scsi spec mandates that any |
| 874 | * untransferred sense data should be interpreted as being zero. |
| 875 | */ |
| 876 | memset(scmd->sense_buffer, 0, sizeof(scmd->sense_buffer)); |
| 877 | |
Patrick Mansfield | 793698c | 2005-05-16 17:42:15 -0700 | [diff] [blame] | 878 | saved_result = scmd->result; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 879 | scmd->request_buffer = NULL; |
| 880 | scmd->request_bufflen = 0; |
| 881 | scmd->use_sg = 0; |
| 882 | scmd->cmd_len = COMMAND_SIZE(scmd->cmnd[0]); |
| 883 | scmd->underflow = 0; |
| 884 | scmd->sc_data_direction = DMA_NONE; |
| 885 | |
| 886 | rtn = scsi_send_eh_cmnd(scmd, START_UNIT_TIMEOUT); |
| 887 | |
| 888 | /* |
| 889 | * when we eventually call scsi_finish, we really wish to complete |
| 890 | * the original request, so let's restore the original data. (db) |
| 891 | */ |
| 892 | scsi_setup_cmd_retry(scmd); |
Patrick Mansfield | 793698c | 2005-05-16 17:42:15 -0700 | [diff] [blame] | 893 | scmd->result = saved_result; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 894 | |
| 895 | /* |
| 896 | * hey, we are done. let's look to see what happened. |
| 897 | */ |
| 898 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: scmd %p rtn %x\n", |
| 899 | __FUNCTION__, scmd, rtn)); |
| 900 | if (rtn == SUCCESS) |
| 901 | return 0; |
| 902 | return 1; |
| 903 | } |
| 904 | |
| 905 | /** |
| 906 | * scsi_eh_stu - send START_UNIT if needed |
| 907 | * @shost: scsi host being recovered. |
| 908 | * @eh_done_q: list_head for processed commands. |
| 909 | * |
| 910 | * Notes: |
| 911 | * If commands are failing due to not ready, initializing command required, |
| 912 | * try revalidating the device, which will end up sending a start unit. |
| 913 | **/ |
| 914 | static int scsi_eh_stu(struct Scsi_Host *shost, |
| 915 | struct list_head *work_q, |
| 916 | struct list_head *done_q) |
| 917 | { |
Christoph Hellwig | 937abeaa | 2005-06-19 13:43:56 +0200 | [diff] [blame] | 918 | struct scsi_cmnd *scmd, *stu_scmd, *next; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 919 | struct scsi_device *sdev; |
| 920 | |
| 921 | shost_for_each_device(sdev, shost) { |
| 922 | stu_scmd = NULL; |
| 923 | list_for_each_entry(scmd, work_q, eh_entry) |
| 924 | if (scmd->device == sdev && SCSI_SENSE_VALID(scmd) && |
| 925 | scsi_check_sense(scmd) == FAILED ) { |
| 926 | stu_scmd = scmd; |
| 927 | break; |
| 928 | } |
| 929 | |
| 930 | if (!stu_scmd) |
| 931 | continue; |
| 932 | |
| 933 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending START_UNIT to sdev:" |
| 934 | " 0x%p\n", current->comm, sdev)); |
| 935 | |
| 936 | if (!scsi_eh_try_stu(stu_scmd)) { |
| 937 | if (!scsi_device_online(sdev) || |
| 938 | !scsi_eh_tur(stu_scmd)) { |
Christoph Hellwig | 937abeaa | 2005-06-19 13:43:56 +0200 | [diff] [blame] | 939 | list_for_each_entry_safe(scmd, next, |
| 940 | work_q, eh_entry) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 941 | if (scmd->device == sdev) |
| 942 | scsi_eh_finish_cmd(scmd, done_q); |
| 943 | } |
| 944 | } |
| 945 | } else { |
| 946 | SCSI_LOG_ERROR_RECOVERY(3, |
| 947 | printk("%s: START_UNIT failed to sdev:" |
| 948 | " 0x%p\n", current->comm, sdev)); |
| 949 | } |
| 950 | } |
| 951 | |
| 952 | return list_empty(work_q); |
| 953 | } |
| 954 | |
| 955 | |
| 956 | /** |
| 957 | * scsi_eh_bus_device_reset - send bdr if needed |
| 958 | * @shost: scsi host being recovered. |
| 959 | * @eh_done_q: list_head for processed commands. |
| 960 | * |
| 961 | * Notes: |
| 962 | * Try a bus device reset. still, look to see whether we have multiple |
| 963 | * devices that are jammed or not - if we have multiple devices, it |
| 964 | * makes no sense to try bus_device_reset - we really would need to try |
| 965 | * a bus_reset instead. |
| 966 | **/ |
| 967 | static int scsi_eh_bus_device_reset(struct Scsi_Host *shost, |
| 968 | struct list_head *work_q, |
| 969 | struct list_head *done_q) |
| 970 | { |
Christoph Hellwig | 937abeaa | 2005-06-19 13:43:56 +0200 | [diff] [blame] | 971 | struct scsi_cmnd *scmd, *bdr_scmd, *next; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 972 | struct scsi_device *sdev; |
| 973 | int rtn; |
| 974 | |
| 975 | shost_for_each_device(sdev, shost) { |
| 976 | bdr_scmd = NULL; |
| 977 | list_for_each_entry(scmd, work_q, eh_entry) |
| 978 | if (scmd->device == sdev) { |
| 979 | bdr_scmd = scmd; |
| 980 | break; |
| 981 | } |
| 982 | |
| 983 | if (!bdr_scmd) |
| 984 | continue; |
| 985 | |
| 986 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending BDR sdev:" |
| 987 | " 0x%p\n", current->comm, |
| 988 | sdev)); |
| 989 | rtn = scsi_try_bus_device_reset(bdr_scmd); |
| 990 | if (rtn == SUCCESS) { |
| 991 | if (!scsi_device_online(sdev) || |
| 992 | !scsi_eh_tur(bdr_scmd)) { |
Christoph Hellwig | 937abeaa | 2005-06-19 13:43:56 +0200 | [diff] [blame] | 993 | list_for_each_entry_safe(scmd, next, |
| 994 | work_q, eh_entry) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 995 | if (scmd->device == sdev) |
| 996 | scsi_eh_finish_cmd(scmd, |
| 997 | done_q); |
| 998 | } |
| 999 | } |
| 1000 | } else { |
| 1001 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: BDR" |
| 1002 | " failed sdev:" |
| 1003 | "0x%p\n", |
| 1004 | current->comm, |
| 1005 | sdev)); |
| 1006 | } |
| 1007 | } |
| 1008 | |
| 1009 | return list_empty(work_q); |
| 1010 | } |
| 1011 | |
| 1012 | /** |
| 1013 | * scsi_try_bus_reset - ask host to perform a bus reset |
| 1014 | * @scmd: SCSI cmd to send bus reset. |
| 1015 | **/ |
| 1016 | static int scsi_try_bus_reset(struct scsi_cmnd *scmd) |
| 1017 | { |
| 1018 | unsigned long flags; |
| 1019 | int rtn; |
| 1020 | |
| 1021 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Snd Bus RST\n", |
| 1022 | __FUNCTION__)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1023 | |
| 1024 | if (!scmd->device->host->hostt->eh_bus_reset_handler) |
| 1025 | return FAILED; |
| 1026 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1027 | rtn = scmd->device->host->hostt->eh_bus_reset_handler(scmd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1028 | |
| 1029 | if (rtn == SUCCESS) { |
| 1030 | if (!scmd->device->host->hostt->skip_settle_delay) |
| 1031 | ssleep(BUS_RESET_SETTLE_TIME); |
| 1032 | spin_lock_irqsave(scmd->device->host->host_lock, flags); |
| 1033 | scsi_report_bus_reset(scmd->device->host, scmd->device->channel); |
| 1034 | spin_unlock_irqrestore(scmd->device->host->host_lock, flags); |
| 1035 | } |
| 1036 | |
| 1037 | return rtn; |
| 1038 | } |
| 1039 | |
| 1040 | /** |
| 1041 | * scsi_try_host_reset - ask host adapter to reset itself |
| 1042 | * @scmd: SCSI cmd to send hsot reset. |
| 1043 | **/ |
| 1044 | static int scsi_try_host_reset(struct scsi_cmnd *scmd) |
| 1045 | { |
| 1046 | unsigned long flags; |
| 1047 | int rtn; |
| 1048 | |
| 1049 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Snd Host RST\n", |
| 1050 | __FUNCTION__)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1051 | |
| 1052 | if (!scmd->device->host->hostt->eh_host_reset_handler) |
| 1053 | return FAILED; |
| 1054 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1055 | rtn = scmd->device->host->hostt->eh_host_reset_handler(scmd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1056 | |
| 1057 | if (rtn == SUCCESS) { |
| 1058 | if (!scmd->device->host->hostt->skip_settle_delay) |
| 1059 | ssleep(HOST_RESET_SETTLE_TIME); |
| 1060 | spin_lock_irqsave(scmd->device->host->host_lock, flags); |
| 1061 | scsi_report_bus_reset(scmd->device->host, scmd->device->channel); |
| 1062 | spin_unlock_irqrestore(scmd->device->host->host_lock, flags); |
| 1063 | } |
| 1064 | |
| 1065 | return rtn; |
| 1066 | } |
| 1067 | |
| 1068 | /** |
| 1069 | * scsi_eh_bus_reset - send a bus reset |
| 1070 | * @shost: scsi host being recovered. |
| 1071 | * @eh_done_q: list_head for processed commands. |
| 1072 | **/ |
| 1073 | static int scsi_eh_bus_reset(struct Scsi_Host *shost, |
| 1074 | struct list_head *work_q, |
| 1075 | struct list_head *done_q) |
| 1076 | { |
Christoph Hellwig | 937abeaa | 2005-06-19 13:43:56 +0200 | [diff] [blame] | 1077 | struct scsi_cmnd *scmd, *chan_scmd, *next; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1078 | unsigned int channel; |
| 1079 | int rtn; |
| 1080 | |
| 1081 | /* |
| 1082 | * we really want to loop over the various channels, and do this on |
| 1083 | * a channel by channel basis. we should also check to see if any |
| 1084 | * of the failed commands are on soft_reset devices, and if so, skip |
| 1085 | * the reset. |
| 1086 | */ |
| 1087 | |
| 1088 | for (channel = 0; channel <= shost->max_channel; channel++) { |
| 1089 | chan_scmd = NULL; |
| 1090 | list_for_each_entry(scmd, work_q, eh_entry) { |
| 1091 | if (channel == scmd->device->channel) { |
| 1092 | chan_scmd = scmd; |
| 1093 | break; |
| 1094 | /* |
| 1095 | * FIXME add back in some support for |
| 1096 | * soft_reset devices. |
| 1097 | */ |
| 1098 | } |
| 1099 | } |
| 1100 | |
| 1101 | if (!chan_scmd) |
| 1102 | continue; |
| 1103 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending BRST chan:" |
| 1104 | " %d\n", current->comm, |
| 1105 | channel)); |
| 1106 | rtn = scsi_try_bus_reset(chan_scmd); |
| 1107 | if (rtn == SUCCESS) { |
Christoph Hellwig | 937abeaa | 2005-06-19 13:43:56 +0200 | [diff] [blame] | 1108 | list_for_each_entry_safe(scmd, next, work_q, eh_entry) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1109 | if (channel == scmd->device->channel) |
| 1110 | if (!scsi_device_online(scmd->device) || |
| 1111 | !scsi_eh_tur(scmd)) |
| 1112 | scsi_eh_finish_cmd(scmd, |
| 1113 | done_q); |
| 1114 | } |
| 1115 | } else { |
| 1116 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: BRST" |
| 1117 | " failed chan: %d\n", |
| 1118 | current->comm, |
| 1119 | channel)); |
| 1120 | } |
| 1121 | } |
| 1122 | return list_empty(work_q); |
| 1123 | } |
| 1124 | |
| 1125 | /** |
| 1126 | * scsi_eh_host_reset - send a host reset |
| 1127 | * @work_q: list_head for processed commands. |
| 1128 | * @done_q: list_head for processed commands. |
| 1129 | **/ |
| 1130 | static int scsi_eh_host_reset(struct list_head *work_q, |
| 1131 | struct list_head *done_q) |
| 1132 | { |
Christoph Hellwig | 937abeaa | 2005-06-19 13:43:56 +0200 | [diff] [blame] | 1133 | struct scsi_cmnd *scmd, *next; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1134 | int rtn; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1135 | |
| 1136 | if (!list_empty(work_q)) { |
| 1137 | scmd = list_entry(work_q->next, |
| 1138 | struct scsi_cmnd, eh_entry); |
| 1139 | |
| 1140 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending HRST\n" |
| 1141 | , current->comm)); |
| 1142 | |
| 1143 | rtn = scsi_try_host_reset(scmd); |
| 1144 | if (rtn == SUCCESS) { |
Christoph Hellwig | 937abeaa | 2005-06-19 13:43:56 +0200 | [diff] [blame] | 1145 | list_for_each_entry_safe(scmd, next, work_q, eh_entry) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1146 | if (!scsi_device_online(scmd->device) || |
| 1147 | (!scsi_eh_try_stu(scmd) && !scsi_eh_tur(scmd)) || |
| 1148 | !scsi_eh_tur(scmd)) |
| 1149 | scsi_eh_finish_cmd(scmd, done_q); |
| 1150 | } |
| 1151 | } else { |
| 1152 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: HRST" |
| 1153 | " failed\n", |
| 1154 | current->comm)); |
| 1155 | } |
| 1156 | } |
| 1157 | return list_empty(work_q); |
| 1158 | } |
| 1159 | |
| 1160 | /** |
| 1161 | * scsi_eh_offline_sdevs - offline scsi devices that fail to recover |
| 1162 | * @work_q: list_head for processed commands. |
| 1163 | * @done_q: list_head for processed commands. |
| 1164 | * |
| 1165 | **/ |
| 1166 | static void scsi_eh_offline_sdevs(struct list_head *work_q, |
| 1167 | struct list_head *done_q) |
| 1168 | { |
Christoph Hellwig | 937abeaa | 2005-06-19 13:43:56 +0200 | [diff] [blame] | 1169 | struct scsi_cmnd *scmd, *next; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1170 | |
Christoph Hellwig | 937abeaa | 2005-06-19 13:43:56 +0200 | [diff] [blame] | 1171 | list_for_each_entry_safe(scmd, next, work_q, eh_entry) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1172 | printk(KERN_INFO "scsi: Device offlined - not" |
| 1173 | " ready after error recovery: host" |
| 1174 | " %d channel %d id %d lun %d\n", |
| 1175 | scmd->device->host->host_no, |
| 1176 | scmd->device->channel, |
| 1177 | scmd->device->id, |
| 1178 | scmd->device->lun); |
| 1179 | scsi_device_set_state(scmd->device, SDEV_OFFLINE); |
Christoph Hellwig | 3111b0d | 2005-06-19 13:43:26 +0200 | [diff] [blame] | 1180 | if (scmd->eh_eflags & SCSI_EH_CANCEL_CMD) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1181 | /* |
| 1182 | * FIXME: Handle lost cmds. |
| 1183 | */ |
| 1184 | } |
| 1185 | scsi_eh_finish_cmd(scmd, done_q); |
| 1186 | } |
| 1187 | return; |
| 1188 | } |
| 1189 | |
| 1190 | /** |
| 1191 | * scsi_decide_disposition - Disposition a cmd on return from LLD. |
| 1192 | * @scmd: SCSI cmd to examine. |
| 1193 | * |
| 1194 | * Notes: |
| 1195 | * This is *only* called when we are examining the status after sending |
| 1196 | * out the actual data command. any commands that are queued for error |
| 1197 | * recovery (e.g. test_unit_ready) do *not* come through here. |
| 1198 | * |
| 1199 | * When this routine returns failed, it means the error handler thread |
| 1200 | * is woken. In cases where the error code indicates an error that |
| 1201 | * doesn't require the error handler read (i.e. we don't need to |
| 1202 | * abort/reset), this function should return SUCCESS. |
| 1203 | **/ |
| 1204 | int scsi_decide_disposition(struct scsi_cmnd *scmd) |
| 1205 | { |
| 1206 | int rtn; |
| 1207 | |
| 1208 | /* |
| 1209 | * if the device is offline, then we clearly just pass the result back |
| 1210 | * up to the top level. |
| 1211 | */ |
| 1212 | if (!scsi_device_online(scmd->device)) { |
| 1213 | SCSI_LOG_ERROR_RECOVERY(5, printk("%s: device offline - report" |
| 1214 | " as SUCCESS\n", |
| 1215 | __FUNCTION__)); |
| 1216 | return SUCCESS; |
| 1217 | } |
| 1218 | |
| 1219 | /* |
| 1220 | * first check the host byte, to see if there is anything in there |
| 1221 | * that would indicate what we need to do. |
| 1222 | */ |
| 1223 | switch (host_byte(scmd->result)) { |
| 1224 | case DID_PASSTHROUGH: |
| 1225 | /* |
| 1226 | * no matter what, pass this through to the upper layer. |
| 1227 | * nuke this special code so that it looks like we are saying |
| 1228 | * did_ok. |
| 1229 | */ |
| 1230 | scmd->result &= 0xff00ffff; |
| 1231 | return SUCCESS; |
| 1232 | case DID_OK: |
| 1233 | /* |
| 1234 | * looks good. drop through, and check the next byte. |
| 1235 | */ |
| 1236 | break; |
| 1237 | case DID_NO_CONNECT: |
| 1238 | case DID_BAD_TARGET: |
| 1239 | case DID_ABORT: |
| 1240 | /* |
| 1241 | * note - this means that we just report the status back |
| 1242 | * to the top level driver, not that we actually think |
| 1243 | * that it indicates SUCCESS. |
| 1244 | */ |
| 1245 | return SUCCESS; |
| 1246 | /* |
| 1247 | * when the low level driver returns did_soft_error, |
| 1248 | * it is responsible for keeping an internal retry counter |
| 1249 | * in order to avoid endless loops (db) |
| 1250 | * |
| 1251 | * actually this is a bug in this function here. we should |
| 1252 | * be mindful of the maximum number of retries specified |
| 1253 | * and not get stuck in a loop. |
| 1254 | */ |
| 1255 | case DID_SOFT_ERROR: |
| 1256 | goto maybe_retry; |
| 1257 | case DID_IMM_RETRY: |
| 1258 | return NEEDS_RETRY; |
| 1259 | |
| bf34191 | 2005-04-12 17:49:09 -0500 | [diff] [blame] | 1260 | case DID_REQUEUE: |
| 1261 | return ADD_TO_MLQUEUE; |
| 1262 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1263 | case DID_ERROR: |
| 1264 | if (msg_byte(scmd->result) == COMMAND_COMPLETE && |
| 1265 | status_byte(scmd->result) == RESERVATION_CONFLICT) |
| 1266 | /* |
| 1267 | * execute reservation conflict processing code |
| 1268 | * lower down |
| 1269 | */ |
| 1270 | break; |
| 1271 | /* fallthrough */ |
| 1272 | |
| 1273 | case DID_BUS_BUSY: |
| 1274 | case DID_PARITY: |
| 1275 | goto maybe_retry; |
| 1276 | case DID_TIME_OUT: |
| 1277 | /* |
| 1278 | * when we scan the bus, we get timeout messages for |
| 1279 | * these commands if there is no device available. |
| 1280 | * other hosts report did_no_connect for the same thing. |
| 1281 | */ |
| 1282 | if ((scmd->cmnd[0] == TEST_UNIT_READY || |
| 1283 | scmd->cmnd[0] == INQUIRY)) { |
| 1284 | return SUCCESS; |
| 1285 | } else { |
| 1286 | return FAILED; |
| 1287 | } |
| 1288 | case DID_RESET: |
| 1289 | return SUCCESS; |
| 1290 | default: |
| 1291 | return FAILED; |
| 1292 | } |
| 1293 | |
| 1294 | /* |
| 1295 | * next, check the message byte. |
| 1296 | */ |
| 1297 | if (msg_byte(scmd->result) != COMMAND_COMPLETE) |
| 1298 | return FAILED; |
| 1299 | |
| 1300 | /* |
| 1301 | * check the status byte to see if this indicates anything special. |
| 1302 | */ |
| 1303 | switch (status_byte(scmd->result)) { |
| 1304 | case QUEUE_FULL: |
| 1305 | /* |
| 1306 | * the case of trying to send too many commands to a |
| 1307 | * tagged queueing device. |
| 1308 | */ |
| 1309 | case BUSY: |
| 1310 | /* |
| 1311 | * device can't talk to us at the moment. Should only |
| 1312 | * occur (SAM-3) when the task queue is empty, so will cause |
| 1313 | * the empty queue handling to trigger a stall in the |
| 1314 | * device. |
| 1315 | */ |
| 1316 | return ADD_TO_MLQUEUE; |
| 1317 | case GOOD: |
| 1318 | case COMMAND_TERMINATED: |
| 1319 | case TASK_ABORTED: |
| 1320 | return SUCCESS; |
| 1321 | case CHECK_CONDITION: |
| 1322 | rtn = scsi_check_sense(scmd); |
| 1323 | if (rtn == NEEDS_RETRY) |
| 1324 | goto maybe_retry; |
| 1325 | /* if rtn == FAILED, we have no sense information; |
| 1326 | * returning FAILED will wake the error handler thread |
| 1327 | * to collect the sense and redo the decide |
| 1328 | * disposition */ |
| 1329 | return rtn; |
| 1330 | case CONDITION_GOOD: |
| 1331 | case INTERMEDIATE_GOOD: |
| 1332 | case INTERMEDIATE_C_GOOD: |
| 1333 | case ACA_ACTIVE: |
| 1334 | /* |
| 1335 | * who knows? FIXME(eric) |
| 1336 | */ |
| 1337 | return SUCCESS; |
| 1338 | |
| 1339 | case RESERVATION_CONFLICT: |
| 1340 | printk(KERN_INFO "scsi: reservation conflict: host" |
| 1341 | " %d channel %d id %d lun %d\n", |
| 1342 | scmd->device->host->host_no, scmd->device->channel, |
| 1343 | scmd->device->id, scmd->device->lun); |
| 1344 | return SUCCESS; /* causes immediate i/o error */ |
| 1345 | default: |
| 1346 | return FAILED; |
| 1347 | } |
| 1348 | return FAILED; |
| 1349 | |
| 1350 | maybe_retry: |
| 1351 | |
| 1352 | /* we requeue for retry because the error was retryable, and |
| 1353 | * the request was not marked fast fail. Note that above, |
| 1354 | * even if the request is marked fast fail, we still requeue |
| 1355 | * for queue congestion conditions (QUEUE_FULL or BUSY) */ |
| 1356 | if ((++scmd->retries) < scmd->allowed |
| 1357 | && !blk_noretry_request(scmd->request)) { |
| 1358 | return NEEDS_RETRY; |
| 1359 | } else { |
| 1360 | /* |
| 1361 | * no more retries - report this one back to upper level. |
| 1362 | */ |
| 1363 | return SUCCESS; |
| 1364 | } |
| 1365 | } |
| 1366 | |
| 1367 | /** |
| 1368 | * scsi_eh_lock_done - done function for eh door lock request |
| 1369 | * @scmd: SCSI command block for the door lock request |
| 1370 | * |
| 1371 | * Notes: |
| 1372 | * We completed the asynchronous door lock request, and it has either |
| 1373 | * locked the door or failed. We must free the command structures |
| 1374 | * associated with this request. |
| 1375 | **/ |
| 1376 | static void scsi_eh_lock_done(struct scsi_cmnd *scmd) |
| 1377 | { |
| 1378 | struct scsi_request *sreq = scmd->sc_request; |
| 1379 | |
| 1380 | scsi_release_request(sreq); |
| 1381 | } |
| 1382 | |
| 1383 | |
| 1384 | /** |
| 1385 | * scsi_eh_lock_door - Prevent medium removal for the specified device |
| 1386 | * @sdev: SCSI device to prevent medium removal |
| 1387 | * |
| 1388 | * Locking: |
| 1389 | * We must be called from process context; scsi_allocate_request() |
| 1390 | * may sleep. |
| 1391 | * |
| 1392 | * Notes: |
| 1393 | * We queue up an asynchronous "ALLOW MEDIUM REMOVAL" request on the |
| 1394 | * head of the devices request queue, and continue. |
| 1395 | * |
| 1396 | * Bugs: |
| 1397 | * scsi_allocate_request() may sleep waiting for existing requests to |
| 1398 | * be processed. However, since we haven't kicked off any request |
| 1399 | * processing for this host, this may deadlock. |
| 1400 | * |
| 1401 | * If scsi_allocate_request() fails for what ever reason, we |
| 1402 | * completely forget to lock the door. |
| 1403 | **/ |
| 1404 | static void scsi_eh_lock_door(struct scsi_device *sdev) |
| 1405 | { |
| 1406 | struct scsi_request *sreq = scsi_allocate_request(sdev, GFP_KERNEL); |
| 1407 | |
| 1408 | if (unlikely(!sreq)) { |
| 1409 | printk(KERN_ERR "%s: request allocate failed," |
| 1410 | "prevent media removal cmd not sent\n", __FUNCTION__); |
| 1411 | return; |
| 1412 | } |
| 1413 | |
| 1414 | sreq->sr_cmnd[0] = ALLOW_MEDIUM_REMOVAL; |
| 1415 | sreq->sr_cmnd[1] = 0; |
| 1416 | sreq->sr_cmnd[2] = 0; |
| 1417 | sreq->sr_cmnd[3] = 0; |
| 1418 | sreq->sr_cmnd[4] = SCSI_REMOVAL_PREVENT; |
| 1419 | sreq->sr_cmnd[5] = 0; |
| 1420 | sreq->sr_data_direction = DMA_NONE; |
| 1421 | sreq->sr_bufflen = 0; |
| 1422 | sreq->sr_buffer = NULL; |
| 1423 | sreq->sr_allowed = 5; |
| 1424 | sreq->sr_done = scsi_eh_lock_done; |
| 1425 | sreq->sr_timeout_per_command = 10 * HZ; |
| 1426 | sreq->sr_cmd_len = COMMAND_SIZE(sreq->sr_cmnd[0]); |
| 1427 | |
| 1428 | scsi_insert_special_req(sreq, 1); |
| 1429 | } |
| 1430 | |
| 1431 | |
| 1432 | /** |
| 1433 | * scsi_restart_operations - restart io operations to the specified host. |
| 1434 | * @shost: Host we are restarting. |
| 1435 | * |
| 1436 | * Notes: |
| 1437 | * When we entered the error handler, we blocked all further i/o to |
| 1438 | * this device. we need to 'reverse' this process. |
| 1439 | **/ |
| 1440 | static void scsi_restart_operations(struct Scsi_Host *shost) |
| 1441 | { |
| 1442 | struct scsi_device *sdev; |
| 1443 | |
| 1444 | /* |
| 1445 | * If the door was locked, we need to insert a door lock request |
| 1446 | * onto the head of the SCSI request queue for the device. There |
| 1447 | * is no point trying to lock the door of an off-line device. |
| 1448 | */ |
| 1449 | shost_for_each_device(sdev, shost) { |
| 1450 | if (scsi_device_online(sdev) && sdev->locked) |
| 1451 | scsi_eh_lock_door(sdev); |
| 1452 | } |
| 1453 | |
| 1454 | /* |
| 1455 | * next free up anything directly waiting upon the host. this |
| 1456 | * will be requests for character device operations, and also for |
| 1457 | * ioctls to queued block devices. |
| 1458 | */ |
| 1459 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: waking up host to restart\n", |
| 1460 | __FUNCTION__)); |
| 1461 | |
Mike Anderson | d330187 | 2005-06-16 11:12:38 -0700 | [diff] [blame^] | 1462 | scsi_host_set_state(shost, SHOST_RUNNING); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1463 | |
| 1464 | wake_up(&shost->host_wait); |
| 1465 | |
| 1466 | /* |
| 1467 | * finally we need to re-initiate requests that may be pending. we will |
| 1468 | * have had everything blocked while error handling is taking place, and |
| 1469 | * now that error recovery is done, we will need to ensure that these |
| 1470 | * requests are started. |
| 1471 | */ |
| 1472 | scsi_run_host_queues(shost); |
| 1473 | } |
| 1474 | |
| 1475 | /** |
| 1476 | * scsi_eh_ready_devs - check device ready state and recover if not. |
| 1477 | * @shost: host to be recovered. |
| 1478 | * @eh_done_q: list_head for processed commands. |
| 1479 | * |
| 1480 | **/ |
| 1481 | static void scsi_eh_ready_devs(struct Scsi_Host *shost, |
| 1482 | struct list_head *work_q, |
| 1483 | struct list_head *done_q) |
| 1484 | { |
| 1485 | if (!scsi_eh_stu(shost, work_q, done_q)) |
| 1486 | if (!scsi_eh_bus_device_reset(shost, work_q, done_q)) |
| 1487 | if (!scsi_eh_bus_reset(shost, work_q, done_q)) |
| 1488 | if (!scsi_eh_host_reset(work_q, done_q)) |
| 1489 | scsi_eh_offline_sdevs(work_q, done_q); |
| 1490 | } |
| 1491 | |
| 1492 | /** |
| 1493 | * scsi_eh_flush_done_q - finish processed commands or retry them. |
| 1494 | * @done_q: list_head of processed commands. |
| 1495 | * |
| 1496 | **/ |
| 1497 | static void scsi_eh_flush_done_q(struct list_head *done_q) |
| 1498 | { |
Christoph Hellwig | 937abeaa | 2005-06-19 13:43:56 +0200 | [diff] [blame] | 1499 | struct scsi_cmnd *scmd, *next; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1500 | |
Christoph Hellwig | 937abeaa | 2005-06-19 13:43:56 +0200 | [diff] [blame] | 1501 | list_for_each_entry_safe(scmd, next, done_q, eh_entry) { |
| 1502 | list_del_init(&scmd->eh_entry); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1503 | if (scsi_device_online(scmd->device) && |
| 1504 | !blk_noretry_request(scmd->request) && |
| 1505 | (++scmd->retries < scmd->allowed)) { |
| 1506 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: flush" |
| 1507 | " retry cmd: %p\n", |
| 1508 | current->comm, |
| 1509 | scmd)); |
| 1510 | scsi_queue_insert(scmd, SCSI_MLQUEUE_EH_RETRY); |
| 1511 | } else { |
Patrick Mansfield | 793698c | 2005-05-16 17:42:15 -0700 | [diff] [blame] | 1512 | /* |
| 1513 | * If just we got sense for the device (called |
| 1514 | * scsi_eh_get_sense), scmd->result is already |
| 1515 | * set, do not set DRIVER_TIMEOUT. |
| 1516 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1517 | if (!scmd->result) |
| 1518 | scmd->result |= (DRIVER_TIMEOUT << 24); |
| 1519 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: flush finish" |
| 1520 | " cmd: %p\n", |
| 1521 | current->comm, scmd)); |
| 1522 | scsi_finish_command(scmd); |
| 1523 | } |
| 1524 | } |
| 1525 | } |
| 1526 | |
| 1527 | /** |
| 1528 | * scsi_unjam_host - Attempt to fix a host which has a cmd that failed. |
| 1529 | * @shost: Host to unjam. |
| 1530 | * |
| 1531 | * Notes: |
| 1532 | * When we come in here, we *know* that all commands on the bus have |
| 1533 | * either completed, failed or timed out. we also know that no further |
| 1534 | * commands are being sent to the host, so things are relatively quiet |
| 1535 | * and we have freedom to fiddle with things as we wish. |
| 1536 | * |
| 1537 | * This is only the *default* implementation. it is possible for |
| 1538 | * individual drivers to supply their own version of this function, and |
| 1539 | * if the maintainer wishes to do this, it is strongly suggested that |
| 1540 | * this function be taken as a template and modified. this function |
| 1541 | * was designed to correctly handle problems for about 95% of the |
| 1542 | * different cases out there, and it should always provide at least a |
| 1543 | * reasonable amount of error recovery. |
| 1544 | * |
| 1545 | * Any command marked 'failed' or 'timeout' must eventually have |
| 1546 | * scsi_finish_cmd() called for it. we do all of the retry stuff |
| 1547 | * here, so when we restart the host after we return it should have an |
| 1548 | * empty queue. |
| 1549 | **/ |
| 1550 | static void scsi_unjam_host(struct Scsi_Host *shost) |
| 1551 | { |
| 1552 | unsigned long flags; |
| 1553 | LIST_HEAD(eh_work_q); |
| 1554 | LIST_HEAD(eh_done_q); |
| 1555 | |
| 1556 | spin_lock_irqsave(shost->host_lock, flags); |
| 1557 | list_splice_init(&shost->eh_cmd_q, &eh_work_q); |
| 1558 | spin_unlock_irqrestore(shost->host_lock, flags); |
| 1559 | |
| 1560 | SCSI_LOG_ERROR_RECOVERY(1, scsi_eh_prt_fail_stats(shost, &eh_work_q)); |
| 1561 | |
| 1562 | if (!scsi_eh_get_sense(&eh_work_q, &eh_done_q)) |
| 1563 | if (!scsi_eh_abort_cmds(&eh_work_q, &eh_done_q)) |
| 1564 | scsi_eh_ready_devs(shost, &eh_work_q, &eh_done_q); |
| 1565 | |
| 1566 | scsi_eh_flush_done_q(&eh_done_q); |
| 1567 | } |
| 1568 | |
| 1569 | /** |
| 1570 | * scsi_error_handler - Handle errors/timeouts of SCSI cmds. |
| 1571 | * @data: Host for which we are running. |
| 1572 | * |
| 1573 | * Notes: |
| 1574 | * This is always run in the context of a kernel thread. The idea is |
| 1575 | * that we start this thing up when the kernel starts up (one per host |
| 1576 | * that we detect), and it immediately goes to sleep and waits for some |
| 1577 | * event (i.e. failure). When this takes place, we have the job of |
| 1578 | * trying to unjam the bus and restarting things. |
| 1579 | **/ |
| 1580 | int scsi_error_handler(void *data) |
| 1581 | { |
| 1582 | struct Scsi_Host *shost = (struct Scsi_Host *) data; |
| 1583 | int rtn; |
| 1584 | DECLARE_MUTEX_LOCKED(sem); |
| 1585 | |
| 1586 | /* |
| 1587 | * Flush resources |
| 1588 | */ |
| 1589 | |
| 1590 | daemonize("scsi_eh_%d", shost->host_no); |
| 1591 | |
| 1592 | current->flags |= PF_NOFREEZE; |
| 1593 | |
| 1594 | shost->eh_wait = &sem; |
| 1595 | shost->ehandler = current; |
| 1596 | |
| 1597 | /* |
| 1598 | * Wake up the thread that created us. |
| 1599 | */ |
| 1600 | SCSI_LOG_ERROR_RECOVERY(3, printk("Wake up parent of" |
| 1601 | " scsi_eh_%d\n",shost->host_no)); |
| 1602 | |
| 1603 | complete(shost->eh_notify); |
| 1604 | |
| 1605 | while (1) { |
| 1606 | /* |
| 1607 | * If we get a signal, it means we are supposed to go |
| 1608 | * away and die. This typically happens if the user is |
| 1609 | * trying to unload a module. |
| 1610 | */ |
| 1611 | SCSI_LOG_ERROR_RECOVERY(1, printk("Error handler" |
| 1612 | " scsi_eh_%d" |
| 1613 | " sleeping\n",shost->host_no)); |
| 1614 | |
| 1615 | /* |
| 1616 | * Note - we always use down_interruptible with the semaphore |
| 1617 | * even if the module was loaded as part of the kernel. The |
| 1618 | * reason is that down() will cause this thread to be counted |
| 1619 | * in the load average as a running process, and down |
| 1620 | * interruptible doesn't. Given that we need to allow this |
| 1621 | * thread to die if the driver was loaded as a module, using |
| 1622 | * semaphores isn't unreasonable. |
| 1623 | */ |
| 1624 | down_interruptible(&sem); |
| 1625 | if (shost->eh_kill) |
| 1626 | break; |
| 1627 | |
| 1628 | SCSI_LOG_ERROR_RECOVERY(1, printk("Error handler" |
| 1629 | " scsi_eh_%d waking" |
| 1630 | " up\n",shost->host_no)); |
| 1631 | |
| 1632 | shost->eh_active = 1; |
| 1633 | |
| 1634 | /* |
| 1635 | * We have a host that is failing for some reason. Figure out |
| 1636 | * what we need to do to get it up and online again (if we can). |
| 1637 | * If we fail, we end up taking the thing offline. |
| 1638 | */ |
| 1639 | if (shost->hostt->eh_strategy_handler) |
| 1640 | rtn = shost->hostt->eh_strategy_handler(shost); |
| 1641 | else |
| 1642 | scsi_unjam_host(shost); |
| 1643 | |
| 1644 | shost->eh_active = 0; |
| 1645 | |
| 1646 | /* |
| 1647 | * Note - if the above fails completely, the action is to take |
| 1648 | * individual devices offline and flush the queue of any |
| 1649 | * outstanding requests that may have been pending. When we |
| 1650 | * restart, we restart any I/O to any other devices on the bus |
| 1651 | * which are still online. |
| 1652 | */ |
| 1653 | scsi_restart_operations(shost); |
| 1654 | |
| 1655 | } |
| 1656 | |
| 1657 | SCSI_LOG_ERROR_RECOVERY(1, printk("Error handler scsi_eh_%d" |
| 1658 | " exiting\n",shost->host_no)); |
| 1659 | |
| 1660 | /* |
| 1661 | * Make sure that nobody tries to wake us up again. |
| 1662 | */ |
| 1663 | shost->eh_wait = NULL; |
| 1664 | |
| 1665 | /* |
| 1666 | * Knock this down too. From this point on, the host is flying |
| 1667 | * without a pilot. If this is because the module is being unloaded, |
| 1668 | * that's fine. If the user sent a signal to this thing, we are |
| 1669 | * potentially in real danger. |
| 1670 | */ |
| 1671 | shost->eh_active = 0; |
| 1672 | shost->ehandler = NULL; |
| 1673 | |
| 1674 | /* |
| 1675 | * If anyone is waiting for us to exit (i.e. someone trying to unload |
| 1676 | * a driver), then wake up that process to let them know we are on |
| 1677 | * the way out the door. |
| 1678 | */ |
| 1679 | complete_and_exit(shost->eh_notify, 0); |
| 1680 | return 0; |
| 1681 | } |
| 1682 | |
| 1683 | /* |
| 1684 | * Function: scsi_report_bus_reset() |
| 1685 | * |
| 1686 | * Purpose: Utility function used by low-level drivers to report that |
| 1687 | * they have observed a bus reset on the bus being handled. |
| 1688 | * |
| 1689 | * Arguments: shost - Host in question |
| 1690 | * channel - channel on which reset was observed. |
| 1691 | * |
| 1692 | * Returns: Nothing |
| 1693 | * |
| 1694 | * Lock status: Host lock must be held. |
| 1695 | * |
| 1696 | * Notes: This only needs to be called if the reset is one which |
| 1697 | * originates from an unknown location. Resets originated |
| 1698 | * by the mid-level itself don't need to call this, but there |
| 1699 | * should be no harm. |
| 1700 | * |
| 1701 | * The main purpose of this is to make sure that a CHECK_CONDITION |
| 1702 | * is properly treated. |
| 1703 | */ |
| 1704 | void scsi_report_bus_reset(struct Scsi_Host *shost, int channel) |
| 1705 | { |
| 1706 | struct scsi_device *sdev; |
| 1707 | |
| 1708 | __shost_for_each_device(sdev, shost) { |
| 1709 | if (channel == sdev->channel) { |
| 1710 | sdev->was_reset = 1; |
| 1711 | sdev->expecting_cc_ua = 1; |
| 1712 | } |
| 1713 | } |
| 1714 | } |
| 1715 | EXPORT_SYMBOL(scsi_report_bus_reset); |
| 1716 | |
| 1717 | /* |
| 1718 | * Function: scsi_report_device_reset() |
| 1719 | * |
| 1720 | * Purpose: Utility function used by low-level drivers to report that |
| 1721 | * they have observed a device reset on the device being handled. |
| 1722 | * |
| 1723 | * Arguments: shost - Host in question |
| 1724 | * channel - channel on which reset was observed |
| 1725 | * target - target on which reset was observed |
| 1726 | * |
| 1727 | * Returns: Nothing |
| 1728 | * |
| 1729 | * Lock status: Host lock must be held |
| 1730 | * |
| 1731 | * Notes: This only needs to be called if the reset is one which |
| 1732 | * originates from an unknown location. Resets originated |
| 1733 | * by the mid-level itself don't need to call this, but there |
| 1734 | * should be no harm. |
| 1735 | * |
| 1736 | * The main purpose of this is to make sure that a CHECK_CONDITION |
| 1737 | * is properly treated. |
| 1738 | */ |
| 1739 | void scsi_report_device_reset(struct Scsi_Host *shost, int channel, int target) |
| 1740 | { |
| 1741 | struct scsi_device *sdev; |
| 1742 | |
| 1743 | __shost_for_each_device(sdev, shost) { |
| 1744 | if (channel == sdev->channel && |
| 1745 | target == sdev->id) { |
| 1746 | sdev->was_reset = 1; |
| 1747 | sdev->expecting_cc_ua = 1; |
| 1748 | } |
| 1749 | } |
| 1750 | } |
| 1751 | EXPORT_SYMBOL(scsi_report_device_reset); |
| 1752 | |
| 1753 | static void |
| 1754 | scsi_reset_provider_done_command(struct scsi_cmnd *scmd) |
| 1755 | { |
| 1756 | } |
| 1757 | |
| 1758 | /* |
| 1759 | * Function: scsi_reset_provider |
| 1760 | * |
| 1761 | * Purpose: Send requested reset to a bus or device at any phase. |
| 1762 | * |
| 1763 | * Arguments: device - device to send reset to |
| 1764 | * flag - reset type (see scsi.h) |
| 1765 | * |
| 1766 | * Returns: SUCCESS/FAILURE. |
| 1767 | * |
| 1768 | * Notes: This is used by the SCSI Generic driver to provide |
| 1769 | * Bus/Device reset capability. |
| 1770 | */ |
| 1771 | int |
| 1772 | scsi_reset_provider(struct scsi_device *dev, int flag) |
| 1773 | { |
| 1774 | struct scsi_cmnd *scmd = scsi_get_command(dev, GFP_KERNEL); |
| 1775 | struct request req; |
| 1776 | int rtn; |
| 1777 | |
| 1778 | scmd->request = &req; |
| 1779 | memset(&scmd->eh_timeout, 0, sizeof(scmd->eh_timeout)); |
| 1780 | scmd->request->rq_status = RQ_SCSI_BUSY; |
Christoph Hellwig | b4edcbc | 2005-06-19 13:40:52 +0200 | [diff] [blame] | 1781 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1782 | memset(&scmd->cmnd, '\0', sizeof(scmd->cmnd)); |
| 1783 | |
| 1784 | scmd->scsi_done = scsi_reset_provider_done_command; |
| 1785 | scmd->done = NULL; |
| 1786 | scmd->buffer = NULL; |
| 1787 | scmd->bufflen = 0; |
| 1788 | scmd->request_buffer = NULL; |
| 1789 | scmd->request_bufflen = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1790 | |
| 1791 | scmd->cmd_len = 0; |
| 1792 | |
| 1793 | scmd->sc_data_direction = DMA_BIDIRECTIONAL; |
| 1794 | scmd->sc_request = NULL; |
| 1795 | scmd->sc_magic = SCSI_CMND_MAGIC; |
| 1796 | |
| 1797 | init_timer(&scmd->eh_timeout); |
| 1798 | |
| 1799 | /* |
| 1800 | * Sometimes the command can get back into the timer chain, |
| 1801 | * so use the pid as an identifier. |
| 1802 | */ |
| 1803 | scmd->pid = 0; |
| 1804 | |
| 1805 | switch (flag) { |
| 1806 | case SCSI_TRY_RESET_DEVICE: |
| 1807 | rtn = scsi_try_bus_device_reset(scmd); |
| 1808 | if (rtn == SUCCESS) |
| 1809 | break; |
| 1810 | /* FALLTHROUGH */ |
| 1811 | case SCSI_TRY_RESET_BUS: |
| 1812 | rtn = scsi_try_bus_reset(scmd); |
| 1813 | if (rtn == SUCCESS) |
| 1814 | break; |
| 1815 | /* FALLTHROUGH */ |
| 1816 | case SCSI_TRY_RESET_HOST: |
| 1817 | rtn = scsi_try_host_reset(scmd); |
| 1818 | break; |
| 1819 | default: |
| 1820 | rtn = FAILED; |
| 1821 | } |
| 1822 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1823 | scsi_next_command(scmd); |
| 1824 | return rtn; |
| 1825 | } |
| 1826 | EXPORT_SYMBOL(scsi_reset_provider); |
| 1827 | |
| 1828 | /** |
| 1829 | * scsi_normalize_sense - normalize main elements from either fixed or |
| 1830 | * descriptor sense data format into a common format. |
| 1831 | * |
| 1832 | * @sense_buffer: byte array containing sense data returned by device |
| 1833 | * @sb_len: number of valid bytes in sense_buffer |
| 1834 | * @sshdr: pointer to instance of structure that common |
| 1835 | * elements are written to. |
| 1836 | * |
| 1837 | * Notes: |
| 1838 | * The "main elements" from sense data are: response_code, sense_key, |
| 1839 | * asc, ascq and additional_length (only for descriptor format). |
| 1840 | * |
| 1841 | * Typically this function can be called after a device has |
| 1842 | * responded to a SCSI command with the CHECK_CONDITION status. |
| 1843 | * |
| 1844 | * Return value: |
| 1845 | * 1 if valid sense data information found, else 0; |
| 1846 | **/ |
| 1847 | int scsi_normalize_sense(const u8 *sense_buffer, int sb_len, |
| 1848 | struct scsi_sense_hdr *sshdr) |
| 1849 | { |
| 1850 | if (!sense_buffer || !sb_len || (sense_buffer[0] & 0x70) != 0x70) |
| 1851 | return 0; |
| 1852 | |
| 1853 | memset(sshdr, 0, sizeof(struct scsi_sense_hdr)); |
| 1854 | |
| 1855 | sshdr->response_code = (sense_buffer[0] & 0x7f); |
| 1856 | if (sshdr->response_code >= 0x72) { |
| 1857 | /* |
| 1858 | * descriptor format |
| 1859 | */ |
| 1860 | if (sb_len > 1) |
| 1861 | sshdr->sense_key = (sense_buffer[1] & 0xf); |
| 1862 | if (sb_len > 2) |
| 1863 | sshdr->asc = sense_buffer[2]; |
| 1864 | if (sb_len > 3) |
| 1865 | sshdr->ascq = sense_buffer[3]; |
| 1866 | if (sb_len > 7) |
| 1867 | sshdr->additional_length = sense_buffer[7]; |
| 1868 | } else { |
| 1869 | /* |
| 1870 | * fixed format |
| 1871 | */ |
| 1872 | if (sb_len > 2) |
| 1873 | sshdr->sense_key = (sense_buffer[2] & 0xf); |
| 1874 | if (sb_len > 7) { |
| 1875 | sb_len = (sb_len < (sense_buffer[7] + 8)) ? |
| 1876 | sb_len : (sense_buffer[7] + 8); |
| 1877 | if (sb_len > 12) |
| 1878 | sshdr->asc = sense_buffer[12]; |
| 1879 | if (sb_len > 13) |
| 1880 | sshdr->ascq = sense_buffer[13]; |
| 1881 | } |
| 1882 | } |
| 1883 | |
| 1884 | return 1; |
| 1885 | } |
| 1886 | EXPORT_SYMBOL(scsi_normalize_sense); |
| 1887 | |
| 1888 | int scsi_request_normalize_sense(struct scsi_request *sreq, |
| 1889 | struct scsi_sense_hdr *sshdr) |
| 1890 | { |
| 1891 | return scsi_normalize_sense(sreq->sr_sense_buffer, |
| 1892 | sizeof(sreq->sr_sense_buffer), sshdr); |
| 1893 | } |
| 1894 | EXPORT_SYMBOL(scsi_request_normalize_sense); |
| 1895 | |
| 1896 | int scsi_command_normalize_sense(struct scsi_cmnd *cmd, |
| 1897 | struct scsi_sense_hdr *sshdr) |
| 1898 | { |
| 1899 | return scsi_normalize_sense(cmd->sense_buffer, |
| 1900 | sizeof(cmd->sense_buffer), sshdr); |
| 1901 | } |
| 1902 | EXPORT_SYMBOL(scsi_command_normalize_sense); |
| 1903 | |
| 1904 | /** |
| 1905 | * scsi_sense_desc_find - search for a given descriptor type in |
| 1906 | * descriptor sense data format. |
| 1907 | * |
| 1908 | * @sense_buffer: byte array of descriptor format sense data |
| 1909 | * @sb_len: number of valid bytes in sense_buffer |
| 1910 | * @desc_type: value of descriptor type to find |
| 1911 | * (e.g. 0 -> information) |
| 1912 | * |
| 1913 | * Notes: |
| 1914 | * only valid when sense data is in descriptor format |
| 1915 | * |
| 1916 | * Return value: |
| 1917 | * pointer to start of (first) descriptor if found else NULL |
| 1918 | **/ |
| 1919 | const u8 * scsi_sense_desc_find(const u8 * sense_buffer, int sb_len, |
| 1920 | int desc_type) |
| 1921 | { |
| 1922 | int add_sen_len, add_len, desc_len, k; |
| 1923 | const u8 * descp; |
| 1924 | |
| 1925 | if ((sb_len < 8) || (0 == (add_sen_len = sense_buffer[7]))) |
| 1926 | return NULL; |
| 1927 | if ((sense_buffer[0] < 0x72) || (sense_buffer[0] > 0x73)) |
| 1928 | return NULL; |
| 1929 | add_sen_len = (add_sen_len < (sb_len - 8)) ? |
| 1930 | add_sen_len : (sb_len - 8); |
| 1931 | descp = &sense_buffer[8]; |
| 1932 | for (desc_len = 0, k = 0; k < add_sen_len; k += desc_len) { |
| 1933 | descp += desc_len; |
| 1934 | add_len = (k < (add_sen_len - 1)) ? descp[1]: -1; |
| 1935 | desc_len = add_len + 2; |
| 1936 | if (descp[0] == desc_type) |
| 1937 | return descp; |
| 1938 | if (add_len < 0) // short descriptor ?? |
| 1939 | break; |
| 1940 | } |
| 1941 | return NULL; |
| 1942 | } |
| 1943 | EXPORT_SYMBOL(scsi_sense_desc_find); |
| 1944 | |
| 1945 | /** |
| 1946 | * scsi_get_sense_info_fld - attempts to get information field from |
| 1947 | * sense data (either fixed or descriptor format) |
| 1948 | * |
| 1949 | * @sense_buffer: byte array of sense data |
| 1950 | * @sb_len: number of valid bytes in sense_buffer |
| 1951 | * @info_out: pointer to 64 integer where 8 or 4 byte information |
| 1952 | * field will be placed if found. |
| 1953 | * |
| 1954 | * Return value: |
| 1955 | * 1 if information field found, 0 if not found. |
| 1956 | **/ |
| 1957 | int scsi_get_sense_info_fld(const u8 * sense_buffer, int sb_len, |
| 1958 | u64 * info_out) |
| 1959 | { |
| 1960 | int j; |
| 1961 | const u8 * ucp; |
| 1962 | u64 ull; |
| 1963 | |
| 1964 | if (sb_len < 7) |
| 1965 | return 0; |
| 1966 | switch (sense_buffer[0] & 0x7f) { |
| 1967 | case 0x70: |
| 1968 | case 0x71: |
| 1969 | if (sense_buffer[0] & 0x80) { |
| 1970 | *info_out = (sense_buffer[3] << 24) + |
| 1971 | (sense_buffer[4] << 16) + |
| 1972 | (sense_buffer[5] << 8) + sense_buffer[6]; |
| 1973 | return 1; |
| 1974 | } else |
| 1975 | return 0; |
| 1976 | case 0x72: |
| 1977 | case 0x73: |
| 1978 | ucp = scsi_sense_desc_find(sense_buffer, sb_len, |
| 1979 | 0 /* info desc */); |
| 1980 | if (ucp && (0xa == ucp[1])) { |
| 1981 | ull = 0; |
| 1982 | for (j = 0; j < 8; ++j) { |
| 1983 | if (j > 0) |
| 1984 | ull <<= 8; |
| 1985 | ull |= ucp[4 + j]; |
| 1986 | } |
| 1987 | *info_out = ull; |
| 1988 | return 1; |
| 1989 | } else |
| 1990 | return 0; |
| 1991 | default: |
| 1992 | return 0; |
| 1993 | } |
| 1994 | } |
| 1995 | EXPORT_SYMBOL(scsi_get_sense_info_fld); |