| 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/gfp.h> |
| 20 | #include <linux/timer.h> |
| 21 | #include <linux/string.h> |
| 22 | #include <linux/kernel.h> |
| 23 | #include <linux/freezer.h> |
| 24 | #include <linux/kthread.h> |
| 25 | #include <linux/interrupt.h> |
| 26 | #include <linux/blkdev.h> |
| 27 | #include <linux/delay.h> |
| 28 | |
| 29 | #include <scsi/scsi.h> |
| 30 | #include <scsi/scsi_cmnd.h> |
| 31 | #include <scsi/scsi_dbg.h> |
| 32 | #include <scsi/scsi_device.h> |
| 33 | #include <scsi/scsi_eh.h> |
| 34 | #include <scsi/scsi_transport.h> |
| 35 | #include <scsi/scsi_host.h> |
| 36 | #include <scsi/scsi_ioctl.h> |
| 37 | |
| 38 | #include "scsi_priv.h" |
| 39 | #include "scsi_logging.h" |
| 40 | #include "scsi_transport_api.h" |
| 41 | |
| 42 | #include <trace/events/scsi.h> |
| 43 | |
| 44 | #define SENSE_TIMEOUT (10*HZ) |
| 45 | |
| 46 | /* |
| 47 | * These should *probably* be handled by the host itself. |
| 48 | * Since it is allowed to sleep, it probably should. |
| 49 | */ |
| 50 | #define BUS_RESET_SETTLE_TIME (10) |
| 51 | #define HOST_RESET_SETTLE_TIME (10) |
| 52 | |
| 53 | static int scsi_eh_try_stu(struct scsi_cmnd *scmd); |
| 54 | |
| 55 | /* called with shost->host_lock held */ |
| 56 | void scsi_eh_wakeup(struct Scsi_Host *shost) |
| 57 | { |
| 58 | if (shost->host_busy == shost->host_failed) { |
| 59 | trace_scsi_eh_wakeup(shost); |
| 60 | wake_up_process(shost->ehandler); |
| 61 | SCSI_LOG_ERROR_RECOVERY(5, |
| 62 | printk("Waking error handler thread\n")); |
| 63 | } |
| 64 | } |
| 65 | |
| 66 | /** |
| 67 | * scsi_schedule_eh - schedule EH for SCSI host |
| 68 | * @shost: SCSI host to invoke error handling on. |
| 69 | * |
| 70 | * Schedule SCSI EH without scmd. |
| 71 | */ |
| 72 | void scsi_schedule_eh(struct Scsi_Host *shost) |
| 73 | { |
| 74 | unsigned long flags; |
| 75 | |
| 76 | spin_lock_irqsave(shost->host_lock, flags); |
| 77 | |
| 78 | if (scsi_host_set_state(shost, SHOST_RECOVERY) == 0 || |
| 79 | scsi_host_set_state(shost, SHOST_CANCEL_RECOVERY) == 0) { |
| 80 | shost->host_eh_scheduled++; |
| 81 | scsi_eh_wakeup(shost); |
| 82 | } |
| 83 | |
| 84 | spin_unlock_irqrestore(shost->host_lock, flags); |
| 85 | } |
| 86 | EXPORT_SYMBOL_GPL(scsi_schedule_eh); |
| 87 | |
| 88 | /** |
| 89 | * scsi_eh_scmd_add - add scsi cmd to error handling. |
| 90 | * @scmd: scmd to run eh on. |
| 91 | * @eh_flag: optional SCSI_EH flag. |
| 92 | * |
| 93 | * Return value: |
| 94 | * 0 on failure. |
| 95 | */ |
| 96 | int scsi_eh_scmd_add(struct scsi_cmnd *scmd, int eh_flag) |
| 97 | { |
| 98 | struct Scsi_Host *shost = scmd->device->host; |
| 99 | unsigned long flags; |
| 100 | int ret = 0; |
| 101 | |
| 102 | if (!shost->ehandler) |
| 103 | return 0; |
| 104 | |
| 105 | spin_lock_irqsave(shost->host_lock, flags); |
| 106 | if (scsi_host_set_state(shost, SHOST_RECOVERY)) |
| 107 | if (scsi_host_set_state(shost, SHOST_CANCEL_RECOVERY)) |
| 108 | goto out_unlock; |
| 109 | |
| 110 | ret = 1; |
| 111 | scmd->eh_eflags |= eh_flag; |
| 112 | list_add_tail(&scmd->eh_entry, &shost->eh_cmd_q); |
| 113 | shost->host_failed++; |
| 114 | scsi_eh_wakeup(shost); |
| 115 | out_unlock: |
| 116 | spin_unlock_irqrestore(shost->host_lock, flags); |
| 117 | return ret; |
| 118 | } |
| 119 | |
| 120 | /** |
| 121 | * scsi_times_out - Timeout function for normal scsi commands. |
| 122 | * @req: request that is timing out. |
| 123 | * |
| 124 | * Notes: |
| 125 | * We do not need to lock this. There is the potential for a race |
| 126 | * only in that the normal completion handling might run, but if the |
| 127 | * normal completion function determines that the timer has already |
| 128 | * fired, then it mustn't do anything. |
| 129 | */ |
| 130 | enum blk_eh_timer_return scsi_times_out(struct request *req) |
| 131 | { |
| 132 | struct scsi_cmnd *scmd = req->special; |
| 133 | enum blk_eh_timer_return rtn = BLK_EH_NOT_HANDLED; |
| 134 | struct Scsi_Host *host = scmd->device->host; |
| 135 | |
| 136 | trace_scsi_dispatch_cmd_timeout(scmd); |
| 137 | scsi_log_completion(scmd, TIMEOUT_ERROR); |
| 138 | |
| 139 | if (host->transportt->eh_timed_out) |
| 140 | rtn = host->transportt->eh_timed_out(scmd); |
| 141 | else if (host->hostt->eh_timed_out) |
| 142 | rtn = host->hostt->eh_timed_out(scmd); |
| 143 | |
| 144 | if (unlikely(rtn == BLK_EH_NOT_HANDLED && |
| 145 | !scsi_eh_scmd_add(scmd, SCSI_EH_CANCEL_CMD))) { |
| 146 | scmd->result |= DID_TIME_OUT << 16; |
| 147 | rtn = BLK_EH_HANDLED; |
| 148 | } |
| 149 | |
| 150 | return rtn; |
| 151 | } |
| 152 | |
| 153 | /** |
| 154 | * scsi_block_when_processing_errors - Prevent cmds from being queued. |
| 155 | * @sdev: Device on which we are performing recovery. |
| 156 | * |
| 157 | * Description: |
| 158 | * We block until the host is out of error recovery, and then check to |
| 159 | * see whether the host or the device is offline. |
| 160 | * |
| 161 | * Return value: |
| 162 | * 0 when dev was taken offline by error recovery. 1 OK to proceed. |
| 163 | */ |
| 164 | int scsi_block_when_processing_errors(struct scsi_device *sdev) |
| 165 | { |
| 166 | int online; |
| 167 | |
| 168 | wait_event(sdev->host->host_wait, !scsi_host_in_recovery(sdev->host)); |
| 169 | |
| 170 | online = scsi_device_online(sdev); |
| 171 | |
| 172 | SCSI_LOG_ERROR_RECOVERY(5, printk("%s: rtn: %d\n", __func__, |
| 173 | online)); |
| 174 | |
| 175 | return online; |
| 176 | } |
| 177 | EXPORT_SYMBOL(scsi_block_when_processing_errors); |
| 178 | |
| 179 | #ifdef CONFIG_SCSI_LOGGING |
| 180 | /** |
| 181 | * scsi_eh_prt_fail_stats - Log info on failures. |
| 182 | * @shost: scsi host being recovered. |
| 183 | * @work_q: Queue of scsi cmds to process. |
| 184 | */ |
| 185 | static inline void scsi_eh_prt_fail_stats(struct Scsi_Host *shost, |
| 186 | struct list_head *work_q) |
| 187 | { |
| 188 | struct scsi_cmnd *scmd; |
| 189 | struct scsi_device *sdev; |
| 190 | int total_failures = 0; |
| 191 | int cmd_failed = 0; |
| 192 | int cmd_cancel = 0; |
| 193 | int devices_failed = 0; |
| 194 | |
| 195 | shost_for_each_device(sdev, shost) { |
| 196 | list_for_each_entry(scmd, work_q, eh_entry) { |
| 197 | if (scmd->device == sdev) { |
| 198 | ++total_failures; |
| 199 | if (scmd->eh_eflags & SCSI_EH_CANCEL_CMD) |
| 200 | ++cmd_cancel; |
| 201 | else |
| 202 | ++cmd_failed; |
| 203 | } |
| 204 | } |
| 205 | |
| 206 | if (cmd_cancel || cmd_failed) { |
| 207 | SCSI_LOG_ERROR_RECOVERY(3, |
| 208 | sdev_printk(KERN_INFO, sdev, |
| 209 | "%s: cmds failed: %d, cancel: %d\n", |
| 210 | __func__, cmd_failed, |
| 211 | cmd_cancel)); |
| 212 | cmd_cancel = 0; |
| 213 | cmd_failed = 0; |
| 214 | ++devices_failed; |
| 215 | } |
| 216 | } |
| 217 | |
| 218 | SCSI_LOG_ERROR_RECOVERY(2, printk("Total of %d commands on %d" |
| 219 | " devices require eh work\n", |
| 220 | total_failures, devices_failed)); |
| 221 | } |
| 222 | #endif |
| 223 | |
| 224 | /** |
| 225 | * scsi_check_sense - Examine scsi cmd sense |
| 226 | * @scmd: Cmd to have sense checked. |
| 227 | * |
| 228 | * Return value: |
| 229 | * SUCCESS or FAILED or NEEDS_RETRY or TARGET_ERROR |
| 230 | * |
| 231 | * Notes: |
| 232 | * When a deferred error is detected the current command has |
| 233 | * not been executed and needs retrying. |
| 234 | */ |
| 235 | static int scsi_check_sense(struct scsi_cmnd *scmd) |
| 236 | { |
| 237 | struct scsi_device *sdev = scmd->device; |
| 238 | struct scsi_sense_hdr sshdr; |
| 239 | |
| 240 | if (! scsi_command_normalize_sense(scmd, &sshdr)) |
| 241 | return FAILED; /* no valid sense data */ |
| 242 | |
| 243 | if (scsi_sense_is_deferred(&sshdr)) |
| 244 | return NEEDS_RETRY; |
| 245 | |
| 246 | if (sdev->scsi_dh_data && sdev->scsi_dh_data->scsi_dh && |
| 247 | sdev->scsi_dh_data->scsi_dh->check_sense) { |
| 248 | int rc; |
| 249 | |
| 250 | rc = sdev->scsi_dh_data->scsi_dh->check_sense(sdev, &sshdr); |
| 251 | if (rc != SCSI_RETURN_NOT_HANDLED) |
| 252 | return rc; |
| 253 | /* handler does not care. Drop down to default handling */ |
| 254 | } |
| 255 | |
| 256 | /* |
| 257 | * Previous logic looked for FILEMARK, EOM or ILI which are |
| 258 | * mainly associated with tapes and returned SUCCESS. |
| 259 | */ |
| 260 | if (sshdr.response_code == 0x70) { |
| 261 | /* fixed format */ |
| 262 | if (scmd->sense_buffer[2] & 0xe0) |
| 263 | return SUCCESS; |
| 264 | } else { |
| 265 | /* |
| 266 | * descriptor format: look for "stream commands sense data |
| 267 | * descriptor" (see SSC-3). Assume single sense data |
| 268 | * descriptor. Ignore ILI from SBC-2 READ LONG and WRITE LONG. |
| 269 | */ |
| 270 | if ((sshdr.additional_length > 3) && |
| 271 | (scmd->sense_buffer[8] == 0x4) && |
| 272 | (scmd->sense_buffer[11] & 0xe0)) |
| 273 | return SUCCESS; |
| 274 | } |
| 275 | |
| 276 | switch (sshdr.sense_key) { |
| 277 | case NO_SENSE: |
| 278 | return SUCCESS; |
| 279 | case RECOVERED_ERROR: |
| 280 | return /* soft_error */ SUCCESS; |
| 281 | |
| 282 | case ABORTED_COMMAND: |
| 283 | if (sshdr.asc == 0x10) /* DIF */ |
| 284 | return SUCCESS; |
| 285 | |
| 286 | return NEEDS_RETRY; |
| 287 | case NOT_READY: |
| 288 | case UNIT_ATTENTION: |
| 289 | /* |
| 290 | * if we are expecting a cc/ua because of a bus reset that we |
| 291 | * performed, treat this just as a retry. otherwise this is |
| 292 | * information that we should pass up to the upper-level driver |
| 293 | * so that we can deal with it there. |
| 294 | */ |
| 295 | if (scmd->device->expecting_cc_ua) { |
| 296 | /* |
| 297 | * Because some device does not queue unit |
| 298 | * attentions correctly, we carefully check |
| 299 | * additional sense code and qualifier so as |
| 300 | * not to squash media change unit attention. |
| 301 | */ |
| 302 | if (sshdr.asc != 0x28 || sshdr.ascq != 0x00) { |
| 303 | scmd->device->expecting_cc_ua = 0; |
| 304 | return NEEDS_RETRY; |
| 305 | } |
| 306 | } |
| 307 | /* |
| 308 | * if the device is in the process of becoming ready, we |
| 309 | * should retry. |
| 310 | */ |
| 311 | if ((sshdr.asc == 0x04) && (sshdr.ascq == 0x01)) |
| 312 | return NEEDS_RETRY; |
| 313 | /* |
| 314 | * if the device is not started, we need to wake |
| 315 | * the error handler to start the motor |
| 316 | */ |
| 317 | if (scmd->device->allow_restart && |
| 318 | (sshdr.asc == 0x04) && (sshdr.ascq == 0x02)) |
| 319 | return FAILED; |
| 320 | |
| 321 | if (sshdr.asc == 0x3f && sshdr.ascq == 0x0e) |
| 322 | scmd_printk(KERN_WARNING, scmd, |
| 323 | "Warning! Received an indication that the " |
| 324 | "LUN assignments on this target have " |
| 325 | "changed. The Linux SCSI layer does not " |
| 326 | "automatically remap LUN assignments.\n"); |
| 327 | else if (sshdr.asc == 0x3f) |
| 328 | scmd_printk(KERN_WARNING, scmd, |
| 329 | "Warning! Received an indication that the " |
| 330 | "operating parameters on this target have " |
| 331 | "changed. The Linux SCSI layer does not " |
| 332 | "automatically adjust these parameters.\n"); |
| 333 | |
| 334 | if (sshdr.asc == 0x38 && sshdr.ascq == 0x07) |
| 335 | scmd_printk(KERN_WARNING, scmd, |
| 336 | "Warning! Received an indication that the " |
| 337 | "LUN reached a thin provisioning soft " |
| 338 | "threshold.\n"); |
| 339 | |
| 340 | /* |
| 341 | * Pass the UA upwards for a determination in the completion |
| 342 | * functions. |
| 343 | */ |
| 344 | return SUCCESS; |
| 345 | |
| 346 | /* these are not supported */ |
| 347 | case COPY_ABORTED: |
| 348 | case VOLUME_OVERFLOW: |
| 349 | case MISCOMPARE: |
| 350 | case BLANK_CHECK: |
| 351 | case DATA_PROTECT: |
| 352 | return TARGET_ERROR; |
| 353 | |
| 354 | case MEDIUM_ERROR: |
| 355 | if (sshdr.asc == 0x11 || /* UNRECOVERED READ ERR */ |
| 356 | sshdr.asc == 0x13 || /* AMNF DATA FIELD */ |
| 357 | sshdr.asc == 0x14) { /* RECORD NOT FOUND */ |
| 358 | return TARGET_ERROR; |
| 359 | } |
| 360 | return NEEDS_RETRY; |
| 361 | |
| 362 | case HARDWARE_ERROR: |
| 363 | if (scmd->device->retry_hwerror) |
| 364 | return ADD_TO_MLQUEUE; |
| 365 | else |
| 366 | return TARGET_ERROR; |
| 367 | |
| 368 | case ILLEGAL_REQUEST: |
| 369 | default: |
| 370 | return SUCCESS; |
| 371 | } |
| 372 | } |
| 373 | |
| 374 | static void scsi_handle_queue_ramp_up(struct scsi_device *sdev) |
| 375 | { |
| 376 | struct scsi_host_template *sht = sdev->host->hostt; |
| 377 | struct scsi_device *tmp_sdev; |
| 378 | |
| 379 | if (!sht->change_queue_depth || |
| 380 | sdev->queue_depth >= sdev->max_queue_depth) |
| 381 | return; |
| 382 | |
| 383 | if (time_before(jiffies, |
| 384 | sdev->last_queue_ramp_up + sdev->queue_ramp_up_period)) |
| 385 | return; |
| 386 | |
| 387 | if (time_before(jiffies, |
| 388 | sdev->last_queue_full_time + sdev->queue_ramp_up_period)) |
| 389 | return; |
| 390 | |
| 391 | /* |
| 392 | * Walk all devices of a target and do |
| 393 | * ramp up on them. |
| 394 | */ |
| 395 | shost_for_each_device(tmp_sdev, sdev->host) { |
| 396 | if (tmp_sdev->channel != sdev->channel || |
| 397 | tmp_sdev->id != sdev->id || |
| 398 | tmp_sdev->queue_depth == sdev->max_queue_depth) |
| 399 | continue; |
| 400 | /* |
| 401 | * call back into LLD to increase queue_depth by one |
| 402 | * with ramp up reason code. |
| 403 | */ |
| 404 | sht->change_queue_depth(tmp_sdev, tmp_sdev->queue_depth + 1, |
| 405 | SCSI_QDEPTH_RAMP_UP); |
| 406 | sdev->last_queue_ramp_up = jiffies; |
| 407 | } |
| 408 | } |
| 409 | |
| 410 | static void scsi_handle_queue_full(struct scsi_device *sdev) |
| 411 | { |
| 412 | struct scsi_host_template *sht = sdev->host->hostt; |
| 413 | struct scsi_device *tmp_sdev; |
| 414 | |
| 415 | if (!sht->change_queue_depth) |
| 416 | return; |
| 417 | |
| 418 | shost_for_each_device(tmp_sdev, sdev->host) { |
| 419 | if (tmp_sdev->channel != sdev->channel || |
| 420 | tmp_sdev->id != sdev->id) |
| 421 | continue; |
| 422 | /* |
| 423 | * We do not know the number of commands that were at |
| 424 | * the device when we got the queue full so we start |
| 425 | * from the highest possible value and work our way down. |
| 426 | */ |
| 427 | sht->change_queue_depth(tmp_sdev, tmp_sdev->queue_depth - 1, |
| 428 | SCSI_QDEPTH_QFULL); |
| 429 | } |
| 430 | } |
| 431 | |
| 432 | /** |
| 433 | * scsi_eh_completed_normally - Disposition a eh cmd on return from LLD. |
| 434 | * @scmd: SCSI cmd to examine. |
| 435 | * |
| 436 | * Notes: |
| 437 | * This is *only* called when we are examining the status of commands |
| 438 | * queued during error recovery. the main difference here is that we |
| 439 | * don't allow for the possibility of retries here, and we are a lot |
| 440 | * more restrictive about what we consider acceptable. |
| 441 | */ |
| 442 | static int scsi_eh_completed_normally(struct scsi_cmnd *scmd) |
| 443 | { |
| 444 | /* |
| 445 | * first check the host byte, to see if there is anything in there |
| 446 | * that would indicate what we need to do. |
| 447 | */ |
| 448 | if (host_byte(scmd->result) == DID_RESET) { |
| 449 | /* |
| 450 | * rats. we are already in the error handler, so we now |
| 451 | * get to try and figure out what to do next. if the sense |
| 452 | * is valid, we have a pretty good idea of what to do. |
| 453 | * if not, we mark it as FAILED. |
| 454 | */ |
| 455 | return scsi_check_sense(scmd); |
| 456 | } |
| 457 | if (host_byte(scmd->result) != DID_OK) |
| 458 | return FAILED; |
| 459 | |
| 460 | /* |
| 461 | * next, check the message byte. |
| 462 | */ |
| 463 | if (msg_byte(scmd->result) != COMMAND_COMPLETE) |
| 464 | return FAILED; |
| 465 | |
| 466 | /* |
| 467 | * now, check the status byte to see if this indicates |
| 468 | * anything special. |
| 469 | */ |
| 470 | switch (status_byte(scmd->result)) { |
| 471 | case GOOD: |
| 472 | scsi_handle_queue_ramp_up(scmd->device); |
| 473 | case COMMAND_TERMINATED: |
| 474 | return SUCCESS; |
| 475 | case CHECK_CONDITION: |
| 476 | return scsi_check_sense(scmd); |
| 477 | case CONDITION_GOOD: |
| 478 | case INTERMEDIATE_GOOD: |
| 479 | case INTERMEDIATE_C_GOOD: |
| 480 | /* |
| 481 | * who knows? FIXME(eric) |
| 482 | */ |
| 483 | return SUCCESS; |
| 484 | case RESERVATION_CONFLICT: |
| 485 | if (scmd->cmnd[0] == TEST_UNIT_READY) |
| 486 | /* it is a success, we probed the device and |
| 487 | * found it */ |
| 488 | return SUCCESS; |
| 489 | /* otherwise, we failed to send the command */ |
| 490 | return FAILED; |
| 491 | case QUEUE_FULL: |
| 492 | scsi_handle_queue_full(scmd->device); |
| 493 | /* fall through */ |
| 494 | case BUSY: |
| 495 | return NEEDS_RETRY; |
| 496 | default: |
| 497 | return FAILED; |
| 498 | } |
| 499 | return FAILED; |
| 500 | } |
| 501 | |
| 502 | /** |
| 503 | * scsi_eh_done - Completion function for error handling. |
| 504 | * @scmd: Cmd that is done. |
| 505 | */ |
| 506 | static void scsi_eh_done(struct scsi_cmnd *scmd) |
| 507 | { |
| 508 | struct completion *eh_action; |
| 509 | |
| 510 | SCSI_LOG_ERROR_RECOVERY(3, |
| 511 | printk("%s scmd: %p result: %x\n", |
| 512 | __func__, scmd, scmd->result)); |
| 513 | |
| 514 | eh_action = scmd->device->host->eh_action; |
| 515 | if (eh_action) |
| 516 | complete(eh_action); |
| 517 | } |
| 518 | |
| 519 | /** |
| 520 | * scsi_try_host_reset - ask host adapter to reset itself |
| 521 | * @scmd: SCSI cmd to send hsot reset. |
| 522 | */ |
| 523 | static int scsi_try_host_reset(struct scsi_cmnd *scmd) |
| 524 | { |
| 525 | unsigned long flags; |
| 526 | int rtn; |
| 527 | struct Scsi_Host *host = scmd->device->host; |
| 528 | struct scsi_host_template *hostt = host->hostt; |
| 529 | |
| 530 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Snd Host RST\n", |
| 531 | __func__)); |
| 532 | |
| 533 | if (!hostt->eh_host_reset_handler) |
| 534 | return FAILED; |
| 535 | |
| 536 | rtn = hostt->eh_host_reset_handler(scmd); |
| 537 | |
| 538 | if (rtn == SUCCESS) { |
| 539 | if (!hostt->skip_settle_delay) |
| 540 | ssleep(HOST_RESET_SETTLE_TIME); |
| 541 | spin_lock_irqsave(host->host_lock, flags); |
| 542 | scsi_report_bus_reset(host, scmd_channel(scmd)); |
| 543 | spin_unlock_irqrestore(host->host_lock, flags); |
| 544 | } |
| 545 | |
| 546 | return rtn; |
| 547 | } |
| 548 | |
| 549 | /** |
| 550 | * scsi_try_bus_reset - ask host to perform a bus reset |
| 551 | * @scmd: SCSI cmd to send bus reset. |
| 552 | */ |
| 553 | static int scsi_try_bus_reset(struct scsi_cmnd *scmd) |
| 554 | { |
| 555 | unsigned long flags; |
| 556 | int rtn; |
| 557 | struct Scsi_Host *host = scmd->device->host; |
| 558 | struct scsi_host_template *hostt = host->hostt; |
| 559 | |
| 560 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Snd Bus RST\n", |
| 561 | __func__)); |
| 562 | |
| 563 | if (!hostt->eh_bus_reset_handler) |
| 564 | return FAILED; |
| 565 | |
| 566 | rtn = hostt->eh_bus_reset_handler(scmd); |
| 567 | |
| 568 | if (rtn == SUCCESS) { |
| 569 | if (!hostt->skip_settle_delay) |
| 570 | ssleep(BUS_RESET_SETTLE_TIME); |
| 571 | spin_lock_irqsave(host->host_lock, flags); |
| 572 | scsi_report_bus_reset(host, scmd_channel(scmd)); |
| 573 | spin_unlock_irqrestore(host->host_lock, flags); |
| 574 | } |
| 575 | |
| 576 | return rtn; |
| 577 | } |
| 578 | |
| 579 | static void __scsi_report_device_reset(struct scsi_device *sdev, void *data) |
| 580 | { |
| 581 | sdev->was_reset = 1; |
| 582 | sdev->expecting_cc_ua = 1; |
| 583 | } |
| 584 | |
| 585 | /** |
| 586 | * scsi_try_target_reset - Ask host to perform a target reset |
| 587 | * @scmd: SCSI cmd used to send a target reset |
| 588 | * |
| 589 | * Notes: |
| 590 | * There is no timeout for this operation. if this operation is |
| 591 | * unreliable for a given host, then the host itself needs to put a |
| 592 | * timer on it, and set the host back to a consistent state prior to |
| 593 | * returning. |
| 594 | */ |
| 595 | static int scsi_try_target_reset(struct scsi_cmnd *scmd) |
| 596 | { |
| 597 | unsigned long flags; |
| 598 | int rtn; |
| 599 | struct Scsi_Host *host = scmd->device->host; |
| 600 | struct scsi_host_template *hostt = host->hostt; |
| 601 | |
| 602 | if (!hostt->eh_target_reset_handler) |
| 603 | return FAILED; |
| 604 | |
| 605 | rtn = hostt->eh_target_reset_handler(scmd); |
| 606 | if (rtn == SUCCESS) { |
| 607 | spin_lock_irqsave(host->host_lock, flags); |
| 608 | __starget_for_each_device(scsi_target(scmd->device), NULL, |
| 609 | __scsi_report_device_reset); |
| 610 | spin_unlock_irqrestore(host->host_lock, flags); |
| 611 | } |
| 612 | |
| 613 | return rtn; |
| 614 | } |
| 615 | |
| 616 | /** |
| 617 | * scsi_try_bus_device_reset - Ask host to perform a BDR on a dev |
| 618 | * @scmd: SCSI cmd used to send BDR |
| 619 | * |
| 620 | * Notes: |
| 621 | * There is no timeout for this operation. if this operation is |
| 622 | * unreliable for a given host, then the host itself needs to put a |
| 623 | * timer on it, and set the host back to a consistent state prior to |
| 624 | * returning. |
| 625 | */ |
| 626 | static int scsi_try_bus_device_reset(struct scsi_cmnd *scmd) |
| 627 | { |
| 628 | int rtn; |
| 629 | struct scsi_host_template *hostt = scmd->device->host->hostt; |
| 630 | |
| 631 | if (!hostt->eh_device_reset_handler) |
| 632 | return FAILED; |
| 633 | |
| 634 | rtn = hostt->eh_device_reset_handler(scmd); |
| 635 | if (rtn == SUCCESS) |
| 636 | __scsi_report_device_reset(scmd->device, NULL); |
| 637 | return rtn; |
| 638 | } |
| 639 | |
| 640 | static int scsi_try_to_abort_cmd(struct scsi_host_template *hostt, struct scsi_cmnd *scmd) |
| 641 | { |
| 642 | if (!hostt->eh_abort_handler) |
| 643 | return FAILED; |
| 644 | |
| 645 | return hostt->eh_abort_handler(scmd); |
| 646 | } |
| 647 | |
| 648 | static void scsi_abort_eh_cmnd(struct scsi_cmnd *scmd) |
| 649 | { |
| 650 | if (scsi_try_to_abort_cmd(scmd->device->host->hostt, scmd) != SUCCESS) |
| 651 | if (scsi_try_bus_device_reset(scmd) != SUCCESS) |
| 652 | if (scsi_try_target_reset(scmd) != SUCCESS) |
| 653 | if (scsi_try_bus_reset(scmd) != SUCCESS) |
| 654 | scsi_try_host_reset(scmd); |
| 655 | } |
| 656 | |
| 657 | /** |
| 658 | * scsi_eh_prep_cmnd - Save a scsi command info as part of error recory |
| 659 | * @scmd: SCSI command structure to hijack |
| 660 | * @ses: structure to save restore information |
| 661 | * @cmnd: CDB to send. Can be NULL if no new cmnd is needed |
| 662 | * @cmnd_size: size in bytes of @cmnd (must be <= BLK_MAX_CDB) |
| 663 | * @sense_bytes: size of sense data to copy. or 0 (if != 0 @cmnd is ignored) |
| 664 | * |
| 665 | * This function is used to save a scsi command information before re-execution |
| 666 | * as part of the error recovery process. If @sense_bytes is 0 the command |
| 667 | * sent must be one that does not transfer any data. If @sense_bytes != 0 |
| 668 | * @cmnd is ignored and this functions sets up a REQUEST_SENSE command |
| 669 | * and cmnd buffers to read @sense_bytes into @scmd->sense_buffer. |
| 670 | */ |
| 671 | void scsi_eh_prep_cmnd(struct scsi_cmnd *scmd, struct scsi_eh_save *ses, |
| 672 | unsigned char *cmnd, int cmnd_size, unsigned sense_bytes) |
| 673 | { |
| 674 | struct scsi_device *sdev = scmd->device; |
| 675 | |
| 676 | /* |
| 677 | * We need saved copies of a number of fields - this is because |
| 678 | * error handling may need to overwrite these with different values |
| 679 | * to run different commands, and once error handling is complete, |
| 680 | * we will need to restore these values prior to running the actual |
| 681 | * command. |
| 682 | */ |
| 683 | ses->cmd_len = scmd->cmd_len; |
| 684 | ses->cmnd = scmd->cmnd; |
| 685 | ses->data_direction = scmd->sc_data_direction; |
| 686 | ses->sdb = scmd->sdb; |
| 687 | ses->next_rq = scmd->request->next_rq; |
| 688 | ses->result = scmd->result; |
| 689 | ses->underflow = scmd->underflow; |
| 690 | ses->prot_op = scmd->prot_op; |
| 691 | |
| 692 | scmd->prot_op = SCSI_PROT_NORMAL; |
| 693 | scmd->cmnd = ses->eh_cmnd; |
| 694 | memset(scmd->cmnd, 0, BLK_MAX_CDB); |
| 695 | memset(&scmd->sdb, 0, sizeof(scmd->sdb)); |
| 696 | scmd->request->next_rq = NULL; |
| 697 | |
| 698 | if (sense_bytes) { |
| 699 | scmd->sdb.length = min_t(unsigned, SCSI_SENSE_BUFFERSIZE, |
| 700 | sense_bytes); |
| 701 | sg_init_one(&ses->sense_sgl, scmd->sense_buffer, |
| 702 | scmd->sdb.length); |
| 703 | scmd->sdb.table.sgl = &ses->sense_sgl; |
| 704 | scmd->sc_data_direction = DMA_FROM_DEVICE; |
| 705 | scmd->sdb.table.nents = 1; |
| 706 | scmd->cmnd[0] = REQUEST_SENSE; |
| 707 | scmd->cmnd[4] = scmd->sdb.length; |
| 708 | scmd->cmd_len = COMMAND_SIZE(scmd->cmnd[0]); |
| 709 | } else { |
| 710 | scmd->sc_data_direction = DMA_NONE; |
| 711 | if (cmnd) { |
| 712 | BUG_ON(cmnd_size > BLK_MAX_CDB); |
| 713 | memcpy(scmd->cmnd, cmnd, cmnd_size); |
| 714 | scmd->cmd_len = COMMAND_SIZE(scmd->cmnd[0]); |
| 715 | } |
| 716 | } |
| 717 | |
| 718 | scmd->underflow = 0; |
| 719 | |
| 720 | if (sdev->scsi_level <= SCSI_2 && sdev->scsi_level != SCSI_UNKNOWN) |
| 721 | scmd->cmnd[1] = (scmd->cmnd[1] & 0x1f) | |
| 722 | (sdev->lun << 5 & 0xe0); |
| 723 | |
| 724 | /* |
| 725 | * Zero the sense buffer. The scsi spec mandates that any |
| 726 | * untransferred sense data should be interpreted as being zero. |
| 727 | */ |
| 728 | memset(scmd->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE); |
| 729 | } |
| 730 | EXPORT_SYMBOL(scsi_eh_prep_cmnd); |
| 731 | |
| 732 | /** |
| 733 | * scsi_eh_restore_cmnd - Restore a scsi command info as part of error recory |
| 734 | * @scmd: SCSI command structure to restore |
| 735 | * @ses: saved information from a coresponding call to scsi_eh_prep_cmnd |
| 736 | * |
| 737 | * Undo any damage done by above scsi_eh_prep_cmnd(). |
| 738 | */ |
| 739 | void scsi_eh_restore_cmnd(struct scsi_cmnd* scmd, struct scsi_eh_save *ses) |
| 740 | { |
| 741 | /* |
| 742 | * Restore original data |
| 743 | */ |
| 744 | scmd->cmd_len = ses->cmd_len; |
| 745 | scmd->cmnd = ses->cmnd; |
| 746 | scmd->sc_data_direction = ses->data_direction; |
| 747 | scmd->sdb = ses->sdb; |
| 748 | scmd->request->next_rq = ses->next_rq; |
| 749 | scmd->result = ses->result; |
| 750 | scmd->underflow = ses->underflow; |
| 751 | scmd->prot_op = ses->prot_op; |
| 752 | } |
| 753 | EXPORT_SYMBOL(scsi_eh_restore_cmnd); |
| 754 | |
| 755 | /** |
| 756 | * scsi_send_eh_cmnd - submit a scsi command as part of error recory |
| 757 | * @scmd: SCSI command structure to hijack |
| 758 | * @cmnd: CDB to send |
| 759 | * @cmnd_size: size in bytes of @cmnd |
| 760 | * @timeout: timeout for this request |
| 761 | * @sense_bytes: size of sense data to copy or 0 |
| 762 | * |
| 763 | * This function is used to send a scsi command down to a target device |
| 764 | * as part of the error recovery process. See also scsi_eh_prep_cmnd() above. |
| 765 | * |
| 766 | * Return value: |
| 767 | * SUCCESS or FAILED or NEEDS_RETRY |
| 768 | */ |
| 769 | static int scsi_send_eh_cmnd(struct scsi_cmnd *scmd, unsigned char *cmnd, |
| 770 | int cmnd_size, int timeout, unsigned sense_bytes) |
| 771 | { |
| 772 | struct scsi_device *sdev = scmd->device; |
| 773 | struct Scsi_Host *shost = sdev->host; |
| 774 | DECLARE_COMPLETION_ONSTACK(done); |
| 775 | unsigned long timeleft; |
| 776 | struct scsi_eh_save ses; |
| 777 | int rtn; |
| 778 | |
| 779 | scsi_eh_prep_cmnd(scmd, &ses, cmnd, cmnd_size, sense_bytes); |
| 780 | shost->eh_action = &done; |
| 781 | |
| 782 | scsi_log_send(scmd); |
| 783 | scmd->scsi_done = scsi_eh_done; |
| 784 | shost->hostt->queuecommand(shost, scmd); |
| 785 | |
| 786 | timeleft = wait_for_completion_timeout(&done, timeout); |
| 787 | |
| 788 | shost->eh_action = NULL; |
| 789 | |
| 790 | scsi_log_completion(scmd, SUCCESS); |
| 791 | |
| 792 | SCSI_LOG_ERROR_RECOVERY(3, |
| 793 | printk("%s: scmd: %p, timeleft: %ld\n", |
| 794 | __func__, scmd, timeleft)); |
| 795 | |
| 796 | /* |
| 797 | * If there is time left scsi_eh_done got called, and we will |
| 798 | * examine the actual status codes to see whether the command |
| 799 | * actually did complete normally, else tell the host to forget |
| 800 | * about this command. |
| 801 | */ |
| 802 | if (timeleft) { |
| 803 | rtn = scsi_eh_completed_normally(scmd); |
| 804 | SCSI_LOG_ERROR_RECOVERY(3, |
| 805 | printk("%s: scsi_eh_completed_normally %x\n", |
| 806 | __func__, rtn)); |
| 807 | |
| 808 | switch (rtn) { |
| 809 | case SUCCESS: |
| 810 | case NEEDS_RETRY: |
| 811 | case FAILED: |
| 812 | case TARGET_ERROR: |
| 813 | break; |
| 814 | case ADD_TO_MLQUEUE: |
| 815 | rtn = NEEDS_RETRY; |
| 816 | break; |
| 817 | default: |
| 818 | rtn = FAILED; |
| 819 | break; |
| 820 | } |
| 821 | } else { |
| 822 | scsi_abort_eh_cmnd(scmd); |
| 823 | rtn = FAILED; |
| 824 | } |
| 825 | |
| 826 | scsi_eh_restore_cmnd(scmd, &ses); |
| 827 | return rtn; |
| 828 | } |
| 829 | |
| 830 | /** |
| 831 | * scsi_request_sense - Request sense data from a particular target. |
| 832 | * @scmd: SCSI cmd for request sense. |
| 833 | * |
| 834 | * Notes: |
| 835 | * Some hosts automatically obtain this information, others require |
| 836 | * that we obtain it on our own. This function will *not* return until |
| 837 | * the command either times out, or it completes. |
| 838 | */ |
| 839 | static int scsi_request_sense(struct scsi_cmnd *scmd) |
| 840 | { |
| 841 | return scsi_send_eh_cmnd(scmd, NULL, 0, SENSE_TIMEOUT, ~0); |
| 842 | } |
| 843 | |
| 844 | /** |
| 845 | * scsi_eh_finish_cmd - Handle a cmd that eh is finished with. |
| 846 | * @scmd: Original SCSI cmd that eh has finished. |
| 847 | * @done_q: Queue for processed commands. |
| 848 | * |
| 849 | * Notes: |
| 850 | * We don't want to use the normal command completion while we are are |
| 851 | * still handling errors - it may cause other commands to be queued, |
| 852 | * and that would disturb what we are doing. Thus we really want to |
| 853 | * keep a list of pending commands for final completion, and once we |
| 854 | * are ready to leave error handling we handle completion for real. |
| 855 | */ |
| 856 | void scsi_eh_finish_cmd(struct scsi_cmnd *scmd, struct list_head *done_q) |
| 857 | { |
| 858 | scmd->device->host->host_failed--; |
| 859 | scmd->eh_eflags = 0; |
| 860 | list_move_tail(&scmd->eh_entry, done_q); |
| 861 | } |
| 862 | EXPORT_SYMBOL(scsi_eh_finish_cmd); |
| 863 | |
| 864 | /** |
| 865 | * scsi_eh_get_sense - Get device sense data. |
| 866 | * @work_q: Queue of commands to process. |
| 867 | * @done_q: Queue of processed commands. |
| 868 | * |
| 869 | * Description: |
| 870 | * See if we need to request sense information. if so, then get it |
| 871 | * now, so we have a better idea of what to do. |
| 872 | * |
| 873 | * Notes: |
| 874 | * This has the unfortunate side effect that if a shost adapter does |
| 875 | * not automatically request sense information, we end up shutting |
| 876 | * it down before we request it. |
| 877 | * |
| 878 | * All drivers should request sense information internally these days, |
| 879 | * so for now all I have to say is tough noogies if you end up in here. |
| 880 | * |
| 881 | * XXX: Long term this code should go away, but that needs an audit of |
| 882 | * all LLDDs first. |
| 883 | */ |
| 884 | int scsi_eh_get_sense(struct list_head *work_q, |
| 885 | struct list_head *done_q) |
| 886 | { |
| 887 | struct scsi_cmnd *scmd, *next; |
| 888 | int rtn; |
| 889 | |
| 890 | list_for_each_entry_safe(scmd, next, work_q, eh_entry) { |
| 891 | if ((scmd->eh_eflags & SCSI_EH_CANCEL_CMD) || |
| 892 | SCSI_SENSE_VALID(scmd)) |
| 893 | continue; |
| 894 | |
| 895 | SCSI_LOG_ERROR_RECOVERY(2, scmd_printk(KERN_INFO, scmd, |
| 896 | "%s: requesting sense\n", |
| 897 | current->comm)); |
| 898 | rtn = scsi_request_sense(scmd); |
| 899 | if (rtn != SUCCESS) |
| 900 | continue; |
| 901 | |
| 902 | SCSI_LOG_ERROR_RECOVERY(3, printk("sense requested for %p" |
| 903 | " result %x\n", scmd, |
| 904 | scmd->result)); |
| 905 | SCSI_LOG_ERROR_RECOVERY(3, scsi_print_sense("bh", scmd)); |
| 906 | |
| 907 | rtn = scsi_decide_disposition(scmd); |
| 908 | |
| 909 | /* |
| 910 | * if the result was normal, then just pass it along to the |
| 911 | * upper level. |
| 912 | */ |
| 913 | if (rtn == SUCCESS) |
| 914 | /* we don't want this command reissued, just |
| 915 | * finished with the sense data, so set |
| 916 | * retries to the max allowed to ensure it |
| 917 | * won't get reissued */ |
| 918 | scmd->retries = scmd->allowed; |
| 919 | else if (rtn != NEEDS_RETRY) |
| 920 | continue; |
| 921 | |
| 922 | scsi_eh_finish_cmd(scmd, done_q); |
| 923 | } |
| 924 | |
| 925 | return list_empty(work_q); |
| 926 | } |
| 927 | EXPORT_SYMBOL_GPL(scsi_eh_get_sense); |
| 928 | |
| 929 | /** |
| 930 | * scsi_eh_tur - Send TUR to device. |
| 931 | * @scmd: &scsi_cmnd to send TUR |
| 932 | * |
| 933 | * Return value: |
| 934 | * 0 - Device is ready. 1 - Device NOT ready. |
| 935 | */ |
| 936 | static int scsi_eh_tur(struct scsi_cmnd *scmd) |
| 937 | { |
| 938 | static unsigned char tur_command[6] = {TEST_UNIT_READY, 0, 0, 0, 0, 0}; |
| 939 | int retry_cnt = 1, rtn; |
| 940 | |
| 941 | retry_tur: |
| 942 | rtn = scsi_send_eh_cmnd(scmd, tur_command, 6, SENSE_TIMEOUT, 0); |
| 943 | |
| 944 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: scmd %p rtn %x\n", |
| 945 | __func__, scmd, rtn)); |
| 946 | |
| 947 | switch (rtn) { |
| 948 | case NEEDS_RETRY: |
| 949 | if (retry_cnt--) |
| 950 | goto retry_tur; |
| 951 | /*FALLTHRU*/ |
| 952 | case SUCCESS: |
| 953 | return 0; |
| 954 | default: |
| 955 | return 1; |
| 956 | } |
| 957 | } |
| 958 | |
| 959 | /** |
| 960 | * scsi_eh_test_devices - check if devices are responding from error recovery. |
| 961 | * @cmd_list: scsi commands in error recovery. |
| 962 | * @work_q: queue for commands which still need more error recovery |
| 963 | * @done_q: queue for commands which are finished |
| 964 | * @try_stu: boolean on if a STU command should be tried in addition to TUR. |
| 965 | * |
| 966 | * Decription: |
| 967 | * Tests if devices are in a working state. Commands to devices now in |
| 968 | * a working state are sent to the done_q while commands to devices which |
| 969 | * are still failing to respond are returned to the work_q for more |
| 970 | * processing. |
| 971 | **/ |
| 972 | static int scsi_eh_test_devices(struct list_head *cmd_list, |
| 973 | struct list_head *work_q, |
| 974 | struct list_head *done_q, int try_stu) |
| 975 | { |
| 976 | struct scsi_cmnd *scmd, *next; |
| 977 | struct scsi_device *sdev; |
| 978 | int finish_cmds; |
| 979 | |
| 980 | while (!list_empty(cmd_list)) { |
| 981 | scmd = list_entry(cmd_list->next, struct scsi_cmnd, eh_entry); |
| 982 | sdev = scmd->device; |
| 983 | |
| 984 | finish_cmds = !scsi_device_online(scmd->device) || |
| 985 | (try_stu && !scsi_eh_try_stu(scmd) && |
| 986 | !scsi_eh_tur(scmd)) || |
| 987 | !scsi_eh_tur(scmd); |
| 988 | |
| 989 | list_for_each_entry_safe(scmd, next, cmd_list, eh_entry) |
| 990 | if (scmd->device == sdev) { |
| 991 | if (finish_cmds) |
| 992 | scsi_eh_finish_cmd(scmd, done_q); |
| 993 | else |
| 994 | list_move_tail(&scmd->eh_entry, work_q); |
| 995 | } |
| 996 | } |
| 997 | return list_empty(work_q); |
| 998 | } |
| 999 | |
| 1000 | |
| 1001 | /** |
| 1002 | * scsi_eh_abort_cmds - abort pending commands. |
| 1003 | * @work_q: &list_head for pending commands. |
| 1004 | * @done_q: &list_head for processed commands. |
| 1005 | * |
| 1006 | * Decription: |
| 1007 | * Try and see whether or not it makes sense to try and abort the |
| 1008 | * running command. This only works out to be the case if we have one |
| 1009 | * command that has timed out. If the command simply failed, it makes |
| 1010 | * no sense to try and abort the command, since as far as the shost |
| 1011 | * adapter is concerned, it isn't running. |
| 1012 | */ |
| 1013 | static int scsi_eh_abort_cmds(struct list_head *work_q, |
| 1014 | struct list_head *done_q) |
| 1015 | { |
| 1016 | struct scsi_cmnd *scmd, *next; |
| 1017 | LIST_HEAD(check_list); |
| 1018 | int rtn; |
| 1019 | |
| 1020 | list_for_each_entry_safe(scmd, next, work_q, eh_entry) { |
| 1021 | if (!(scmd->eh_eflags & SCSI_EH_CANCEL_CMD)) |
| 1022 | continue; |
| 1023 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: aborting cmd:" |
| 1024 | "0x%p\n", current->comm, |
| 1025 | scmd)); |
| 1026 | rtn = scsi_try_to_abort_cmd(scmd->device->host->hostt, scmd); |
| 1027 | if (rtn == SUCCESS || rtn == FAST_IO_FAIL) { |
| 1028 | scmd->eh_eflags &= ~SCSI_EH_CANCEL_CMD; |
| 1029 | if (rtn == FAST_IO_FAIL) |
| 1030 | scsi_eh_finish_cmd(scmd, done_q); |
| 1031 | else |
| 1032 | list_move_tail(&scmd->eh_entry, &check_list); |
| 1033 | } else |
| 1034 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: aborting" |
| 1035 | " cmd failed:" |
| 1036 | "0x%p\n", |
| 1037 | current->comm, |
| 1038 | scmd)); |
| 1039 | } |
| 1040 | |
| 1041 | return scsi_eh_test_devices(&check_list, work_q, done_q, 0); |
| 1042 | } |
| 1043 | |
| 1044 | /** |
| 1045 | * scsi_eh_try_stu - Send START_UNIT to device. |
| 1046 | * @scmd: &scsi_cmnd to send START_UNIT |
| 1047 | * |
| 1048 | * Return value: |
| 1049 | * 0 - Device is ready. 1 - Device NOT ready. |
| 1050 | */ |
| 1051 | static int scsi_eh_try_stu(struct scsi_cmnd *scmd) |
| 1052 | { |
| 1053 | static unsigned char stu_command[6] = {START_STOP, 0, 0, 0, 1, 0}; |
| 1054 | |
| 1055 | if (scmd->device->allow_restart) { |
| 1056 | int i, rtn = NEEDS_RETRY; |
| 1057 | |
| 1058 | for (i = 0; rtn == NEEDS_RETRY && i < 2; i++) |
| 1059 | rtn = scsi_send_eh_cmnd(scmd, stu_command, 6, scmd->device->request_queue->rq_timeout, 0); |
| 1060 | |
| 1061 | if (rtn == SUCCESS) |
| 1062 | return 0; |
| 1063 | } |
| 1064 | |
| 1065 | return 1; |
| 1066 | } |
| 1067 | |
| 1068 | /** |
| 1069 | * scsi_eh_stu - send START_UNIT if needed |
| 1070 | * @shost: &scsi host being recovered. |
| 1071 | * @work_q: &list_head for pending commands. |
| 1072 | * @done_q: &list_head for processed commands. |
| 1073 | * |
| 1074 | * Notes: |
| 1075 | * If commands are failing due to not ready, initializing command required, |
| 1076 | * try revalidating the device, which will end up sending a start unit. |
| 1077 | */ |
| 1078 | static int scsi_eh_stu(struct Scsi_Host *shost, |
| 1079 | struct list_head *work_q, |
| 1080 | struct list_head *done_q) |
| 1081 | { |
| 1082 | struct scsi_cmnd *scmd, *stu_scmd, *next; |
| 1083 | struct scsi_device *sdev; |
| 1084 | |
| 1085 | shost_for_each_device(sdev, shost) { |
| 1086 | stu_scmd = NULL; |
| 1087 | list_for_each_entry(scmd, work_q, eh_entry) |
| 1088 | if (scmd->device == sdev && SCSI_SENSE_VALID(scmd) && |
| 1089 | scsi_check_sense(scmd) == FAILED ) { |
| 1090 | stu_scmd = scmd; |
| 1091 | break; |
| 1092 | } |
| 1093 | |
| 1094 | if (!stu_scmd) |
| 1095 | continue; |
| 1096 | |
| 1097 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending START_UNIT to sdev:" |
| 1098 | " 0x%p\n", current->comm, sdev)); |
| 1099 | |
| 1100 | if (!scsi_eh_try_stu(stu_scmd)) { |
| 1101 | if (!scsi_device_online(sdev) || |
| 1102 | !scsi_eh_tur(stu_scmd)) { |
| 1103 | list_for_each_entry_safe(scmd, next, |
| 1104 | work_q, eh_entry) { |
| 1105 | if (scmd->device == sdev) |
| 1106 | scsi_eh_finish_cmd(scmd, done_q); |
| 1107 | } |
| 1108 | } |
| 1109 | } else { |
| 1110 | SCSI_LOG_ERROR_RECOVERY(3, |
| 1111 | printk("%s: START_UNIT failed to sdev:" |
| 1112 | " 0x%p\n", current->comm, sdev)); |
| 1113 | } |
| 1114 | } |
| 1115 | |
| 1116 | return list_empty(work_q); |
| 1117 | } |
| 1118 | |
| 1119 | |
| 1120 | /** |
| 1121 | * scsi_eh_bus_device_reset - send bdr if needed |
| 1122 | * @shost: scsi host being recovered. |
| 1123 | * @work_q: &list_head for pending commands. |
| 1124 | * @done_q: &list_head for processed commands. |
| 1125 | * |
| 1126 | * Notes: |
| 1127 | * Try a bus device reset. Still, look to see whether we have multiple |
| 1128 | * devices that are jammed or not - if we have multiple devices, it |
| 1129 | * makes no sense to try bus_device_reset - we really would need to try |
| 1130 | * a bus_reset instead. |
| 1131 | */ |
| 1132 | static int scsi_eh_bus_device_reset(struct Scsi_Host *shost, |
| 1133 | struct list_head *work_q, |
| 1134 | struct list_head *done_q) |
| 1135 | { |
| 1136 | struct scsi_cmnd *scmd, *bdr_scmd, *next; |
| 1137 | struct scsi_device *sdev; |
| 1138 | int rtn; |
| 1139 | |
| 1140 | shost_for_each_device(sdev, shost) { |
| 1141 | bdr_scmd = NULL; |
| 1142 | list_for_each_entry(scmd, work_q, eh_entry) |
| 1143 | if (scmd->device == sdev) { |
| 1144 | bdr_scmd = scmd; |
| 1145 | break; |
| 1146 | } |
| 1147 | |
| 1148 | if (!bdr_scmd) |
| 1149 | continue; |
| 1150 | |
| 1151 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending BDR sdev:" |
| 1152 | " 0x%p\n", current->comm, |
| 1153 | sdev)); |
| 1154 | rtn = scsi_try_bus_device_reset(bdr_scmd); |
| 1155 | if (rtn == SUCCESS || rtn == FAST_IO_FAIL) { |
| 1156 | if (!scsi_device_online(sdev) || |
| 1157 | rtn == FAST_IO_FAIL || |
| 1158 | !scsi_eh_tur(bdr_scmd)) { |
| 1159 | list_for_each_entry_safe(scmd, next, |
| 1160 | work_q, eh_entry) { |
| 1161 | if (scmd->device == sdev) |
| 1162 | scsi_eh_finish_cmd(scmd, |
| 1163 | done_q); |
| 1164 | } |
| 1165 | } |
| 1166 | } else { |
| 1167 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: BDR" |
| 1168 | " failed sdev:" |
| 1169 | "0x%p\n", |
| 1170 | current->comm, |
| 1171 | sdev)); |
| 1172 | } |
| 1173 | } |
| 1174 | |
| 1175 | return list_empty(work_q); |
| 1176 | } |
| 1177 | |
| 1178 | /** |
| 1179 | * scsi_eh_target_reset - send target reset if needed |
| 1180 | * @shost: scsi host being recovered. |
| 1181 | * @work_q: &list_head for pending commands. |
| 1182 | * @done_q: &list_head for processed commands. |
| 1183 | * |
| 1184 | * Notes: |
| 1185 | * Try a target reset. |
| 1186 | */ |
| 1187 | static int scsi_eh_target_reset(struct Scsi_Host *shost, |
| 1188 | struct list_head *work_q, |
| 1189 | struct list_head *done_q) |
| 1190 | { |
| 1191 | LIST_HEAD(tmp_list); |
| 1192 | LIST_HEAD(check_list); |
| 1193 | |
| 1194 | list_splice_init(work_q, &tmp_list); |
| 1195 | |
| 1196 | while (!list_empty(&tmp_list)) { |
| 1197 | struct scsi_cmnd *next, *scmd; |
| 1198 | int rtn; |
| 1199 | unsigned int id; |
| 1200 | |
| 1201 | scmd = list_entry(tmp_list.next, struct scsi_cmnd, eh_entry); |
| 1202 | id = scmd_id(scmd); |
| 1203 | |
| 1204 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending target reset " |
| 1205 | "to target %d\n", |
| 1206 | current->comm, id)); |
| 1207 | rtn = scsi_try_target_reset(scmd); |
| 1208 | if (rtn != SUCCESS && rtn != FAST_IO_FAIL) |
| 1209 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Target reset" |
| 1210 | " failed target: " |
| 1211 | "%d\n", |
| 1212 | current->comm, id)); |
| 1213 | list_for_each_entry_safe(scmd, next, &tmp_list, eh_entry) { |
| 1214 | if (scmd_id(scmd) != id) |
| 1215 | continue; |
| 1216 | |
| 1217 | if (rtn == SUCCESS) |
| 1218 | list_move_tail(&scmd->eh_entry, &check_list); |
| 1219 | else if (rtn == FAST_IO_FAIL) |
| 1220 | scsi_eh_finish_cmd(scmd, done_q); |
| 1221 | else |
| 1222 | /* push back on work queue for further processing */ |
| 1223 | list_move(&scmd->eh_entry, work_q); |
| 1224 | } |
| 1225 | } |
| 1226 | |
| 1227 | return scsi_eh_test_devices(&check_list, work_q, done_q, 0); |
| 1228 | } |
| 1229 | |
| 1230 | /** |
| 1231 | * scsi_eh_bus_reset - send a bus reset |
| 1232 | * @shost: &scsi host being recovered. |
| 1233 | * @work_q: &list_head for pending commands. |
| 1234 | * @done_q: &list_head for processed commands. |
| 1235 | */ |
| 1236 | static int scsi_eh_bus_reset(struct Scsi_Host *shost, |
| 1237 | struct list_head *work_q, |
| 1238 | struct list_head *done_q) |
| 1239 | { |
| 1240 | struct scsi_cmnd *scmd, *chan_scmd, *next; |
| 1241 | LIST_HEAD(check_list); |
| 1242 | unsigned int channel; |
| 1243 | int rtn; |
| 1244 | |
| 1245 | /* |
| 1246 | * we really want to loop over the various channels, and do this on |
| 1247 | * a channel by channel basis. we should also check to see if any |
| 1248 | * of the failed commands are on soft_reset devices, and if so, skip |
| 1249 | * the reset. |
| 1250 | */ |
| 1251 | |
| 1252 | for (channel = 0; channel <= shost->max_channel; channel++) { |
| 1253 | chan_scmd = NULL; |
| 1254 | list_for_each_entry(scmd, work_q, eh_entry) { |
| 1255 | if (channel == scmd_channel(scmd)) { |
| 1256 | chan_scmd = scmd; |
| 1257 | break; |
| 1258 | /* |
| 1259 | * FIXME add back in some support for |
| 1260 | * soft_reset devices. |
| 1261 | */ |
| 1262 | } |
| 1263 | } |
| 1264 | |
| 1265 | if (!chan_scmd) |
| 1266 | continue; |
| 1267 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending BRST chan:" |
| 1268 | " %d\n", current->comm, |
| 1269 | channel)); |
| 1270 | rtn = scsi_try_bus_reset(chan_scmd); |
| 1271 | if (rtn == SUCCESS || rtn == FAST_IO_FAIL) { |
| 1272 | list_for_each_entry_safe(scmd, next, work_q, eh_entry) { |
| 1273 | if (channel == scmd_channel(scmd)) { |
| 1274 | if (rtn == FAST_IO_FAIL) |
| 1275 | scsi_eh_finish_cmd(scmd, |
| 1276 | done_q); |
| 1277 | else |
| 1278 | list_move_tail(&scmd->eh_entry, |
| 1279 | &check_list); |
| 1280 | } |
| 1281 | } |
| 1282 | } else { |
| 1283 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: BRST" |
| 1284 | " failed chan: %d\n", |
| 1285 | current->comm, |
| 1286 | channel)); |
| 1287 | } |
| 1288 | } |
| 1289 | return scsi_eh_test_devices(&check_list, work_q, done_q, 0); |
| 1290 | } |
| 1291 | |
| 1292 | /** |
| 1293 | * scsi_eh_host_reset - send a host reset |
| 1294 | * @work_q: list_head for processed commands. |
| 1295 | * @done_q: list_head for processed commands. |
| 1296 | */ |
| 1297 | static int scsi_eh_host_reset(struct list_head *work_q, |
| 1298 | struct list_head *done_q) |
| 1299 | { |
| 1300 | struct scsi_cmnd *scmd, *next; |
| 1301 | LIST_HEAD(check_list); |
| 1302 | int rtn; |
| 1303 | |
| 1304 | if (!list_empty(work_q)) { |
| 1305 | scmd = list_entry(work_q->next, |
| 1306 | struct scsi_cmnd, eh_entry); |
| 1307 | |
| 1308 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: Sending HRST\n" |
| 1309 | , current->comm)); |
| 1310 | |
| 1311 | rtn = scsi_try_host_reset(scmd); |
| 1312 | if (rtn == SUCCESS) { |
| 1313 | list_splice_init(work_q, &check_list); |
| 1314 | } else if (rtn == FAST_IO_FAIL) { |
| 1315 | list_for_each_entry_safe(scmd, next, work_q, eh_entry) { |
| 1316 | scsi_eh_finish_cmd(scmd, done_q); |
| 1317 | } |
| 1318 | } else { |
| 1319 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: HRST" |
| 1320 | " failed\n", |
| 1321 | current->comm)); |
| 1322 | } |
| 1323 | } |
| 1324 | return scsi_eh_test_devices(&check_list, work_q, done_q, 1); |
| 1325 | } |
| 1326 | |
| 1327 | /** |
| 1328 | * scsi_eh_offline_sdevs - offline scsi devices that fail to recover |
| 1329 | * @work_q: list_head for processed commands. |
| 1330 | * @done_q: list_head for processed commands. |
| 1331 | */ |
| 1332 | static void scsi_eh_offline_sdevs(struct list_head *work_q, |
| 1333 | struct list_head *done_q) |
| 1334 | { |
| 1335 | struct scsi_cmnd *scmd, *next; |
| 1336 | |
| 1337 | list_for_each_entry_safe(scmd, next, work_q, eh_entry) { |
| 1338 | sdev_printk(KERN_INFO, scmd->device, "Device offlined - " |
| 1339 | "not ready after error recovery\n"); |
| 1340 | scsi_device_set_state(scmd->device, SDEV_OFFLINE); |
| 1341 | if (scmd->eh_eflags & SCSI_EH_CANCEL_CMD) { |
| 1342 | /* |
| 1343 | * FIXME: Handle lost cmds. |
| 1344 | */ |
| 1345 | } |
| 1346 | scsi_eh_finish_cmd(scmd, done_q); |
| 1347 | } |
| 1348 | return; |
| 1349 | } |
| 1350 | |
| 1351 | /** |
| 1352 | * scsi_noretry_cmd - determinte if command should be failed fast |
| 1353 | * @scmd: SCSI cmd to examine. |
| 1354 | */ |
| 1355 | int scsi_noretry_cmd(struct scsi_cmnd *scmd) |
| 1356 | { |
| 1357 | switch (host_byte(scmd->result)) { |
| 1358 | case DID_OK: |
| 1359 | break; |
| 1360 | case DID_BUS_BUSY: |
| 1361 | return (scmd->request->cmd_flags & REQ_FAILFAST_TRANSPORT); |
| 1362 | case DID_PARITY: |
| 1363 | return (scmd->request->cmd_flags & REQ_FAILFAST_DEV); |
| 1364 | case DID_ERROR: |
| 1365 | if (msg_byte(scmd->result) == COMMAND_COMPLETE && |
| 1366 | status_byte(scmd->result) == RESERVATION_CONFLICT) |
| 1367 | return 0; |
| 1368 | /* fall through */ |
| 1369 | case DID_SOFT_ERROR: |
| 1370 | return (scmd->request->cmd_flags & REQ_FAILFAST_DRIVER); |
| 1371 | } |
| 1372 | |
| 1373 | switch (status_byte(scmd->result)) { |
| 1374 | case CHECK_CONDITION: |
| 1375 | /* |
| 1376 | * assume caller has checked sense and determinted |
| 1377 | * the check condition was retryable. |
| 1378 | */ |
| 1379 | if (scmd->request->cmd_flags & REQ_FAILFAST_DEV || |
| 1380 | scmd->request->cmd_type == REQ_TYPE_BLOCK_PC) |
| 1381 | return 1; |
| 1382 | } |
| 1383 | |
| 1384 | return 0; |
| 1385 | } |
| 1386 | |
| 1387 | /** |
| 1388 | * scsi_decide_disposition - Disposition a cmd on return from LLD. |
| 1389 | * @scmd: SCSI cmd to examine. |
| 1390 | * |
| 1391 | * Notes: |
| 1392 | * This is *only* called when we are examining the status after sending |
| 1393 | * out the actual data command. any commands that are queued for error |
| 1394 | * recovery (e.g. test_unit_ready) do *not* come through here. |
| 1395 | * |
| 1396 | * When this routine returns failed, it means the error handler thread |
| 1397 | * is woken. In cases where the error code indicates an error that |
| 1398 | * doesn't require the error handler read (i.e. we don't need to |
| 1399 | * abort/reset), this function should return SUCCESS. |
| 1400 | */ |
| 1401 | int scsi_decide_disposition(struct scsi_cmnd *scmd) |
| 1402 | { |
| 1403 | int rtn; |
| 1404 | |
| 1405 | /* |
| 1406 | * if the device is offline, then we clearly just pass the result back |
| 1407 | * up to the top level. |
| 1408 | */ |
| 1409 | if (!scsi_device_online(scmd->device)) { |
| 1410 | SCSI_LOG_ERROR_RECOVERY(5, printk("%s: device offline - report" |
| 1411 | " as SUCCESS\n", |
| 1412 | __func__)); |
| 1413 | return SUCCESS; |
| 1414 | } |
| 1415 | |
| 1416 | /* |
| 1417 | * first check the host byte, to see if there is anything in there |
| 1418 | * that would indicate what we need to do. |
| 1419 | */ |
| 1420 | switch (host_byte(scmd->result)) { |
| 1421 | case DID_PASSTHROUGH: |
| 1422 | /* |
| 1423 | * no matter what, pass this through to the upper layer. |
| 1424 | * nuke this special code so that it looks like we are saying |
| 1425 | * did_ok. |
| 1426 | */ |
| 1427 | scmd->result &= 0xff00ffff; |
| 1428 | return SUCCESS; |
| 1429 | case DID_OK: |
| 1430 | /* |
| 1431 | * looks good. drop through, and check the next byte. |
| 1432 | */ |
| 1433 | break; |
| 1434 | case DID_NO_CONNECT: |
| 1435 | case DID_BAD_TARGET: |
| 1436 | case DID_ABORT: |
| 1437 | /* |
| 1438 | * note - this means that we just report the status back |
| 1439 | * to the top level driver, not that we actually think |
| 1440 | * that it indicates SUCCESS. |
| 1441 | */ |
| 1442 | return SUCCESS; |
| 1443 | /* |
| 1444 | * when the low level driver returns did_soft_error, |
| 1445 | * it is responsible for keeping an internal retry counter |
| 1446 | * in order to avoid endless loops (db) |
| 1447 | * |
| 1448 | * actually this is a bug in this function here. we should |
| 1449 | * be mindful of the maximum number of retries specified |
| 1450 | * and not get stuck in a loop. |
| 1451 | */ |
| 1452 | case DID_SOFT_ERROR: |
| 1453 | goto maybe_retry; |
| 1454 | case DID_IMM_RETRY: |
| 1455 | return NEEDS_RETRY; |
| 1456 | |
| 1457 | case DID_REQUEUE: |
| 1458 | return ADD_TO_MLQUEUE; |
| 1459 | case DID_TRANSPORT_DISRUPTED: |
| 1460 | /* |
| 1461 | * LLD/transport was disrupted during processing of the IO. |
| 1462 | * The transport class is now blocked/blocking, |
| 1463 | * and the transport will decide what to do with the IO |
| 1464 | * based on its timers and recovery capablilities if |
| 1465 | * there are enough retries. |
| 1466 | */ |
| 1467 | goto maybe_retry; |
| 1468 | case DID_TRANSPORT_FAILFAST: |
| 1469 | /* |
| 1470 | * The transport decided to failfast the IO (most likely |
| 1471 | * the fast io fail tmo fired), so send IO directly upwards. |
| 1472 | */ |
| 1473 | return SUCCESS; |
| 1474 | case DID_ERROR: |
| 1475 | if (msg_byte(scmd->result) == COMMAND_COMPLETE && |
| 1476 | status_byte(scmd->result) == RESERVATION_CONFLICT) |
| 1477 | /* |
| 1478 | * execute reservation conflict processing code |
| 1479 | * lower down |
| 1480 | */ |
| 1481 | break; |
| 1482 | /* fallthrough */ |
| 1483 | case DID_BUS_BUSY: |
| 1484 | case DID_PARITY: |
| 1485 | goto maybe_retry; |
| 1486 | case DID_TIME_OUT: |
| 1487 | /* |
| 1488 | * when we scan the bus, we get timeout messages for |
| 1489 | * these commands if there is no device available. |
| 1490 | * other hosts report did_no_connect for the same thing. |
| 1491 | */ |
| 1492 | if ((scmd->cmnd[0] == TEST_UNIT_READY || |
| 1493 | scmd->cmnd[0] == INQUIRY)) { |
| 1494 | return SUCCESS; |
| 1495 | } else { |
| 1496 | return FAILED; |
| 1497 | } |
| 1498 | case DID_RESET: |
| 1499 | return SUCCESS; |
| 1500 | default: |
| 1501 | return FAILED; |
| 1502 | } |
| 1503 | |
| 1504 | /* |
| 1505 | * next, check the message byte. |
| 1506 | */ |
| 1507 | if (msg_byte(scmd->result) != COMMAND_COMPLETE) |
| 1508 | return FAILED; |
| 1509 | |
| 1510 | /* |
| 1511 | * check the status byte to see if this indicates anything special. |
| 1512 | */ |
| 1513 | switch (status_byte(scmd->result)) { |
| 1514 | case QUEUE_FULL: |
| 1515 | scsi_handle_queue_full(scmd->device); |
| 1516 | /* |
| 1517 | * the case of trying to send too many commands to a |
| 1518 | * tagged queueing device. |
| 1519 | */ |
| 1520 | case BUSY: |
| 1521 | /* |
| 1522 | * device can't talk to us at the moment. Should only |
| 1523 | * occur (SAM-3) when the task queue is empty, so will cause |
| 1524 | * the empty queue handling to trigger a stall in the |
| 1525 | * device. |
| 1526 | */ |
| 1527 | return ADD_TO_MLQUEUE; |
| 1528 | case GOOD: |
| 1529 | scsi_handle_queue_ramp_up(scmd->device); |
| 1530 | case COMMAND_TERMINATED: |
| 1531 | return SUCCESS; |
| 1532 | case TASK_ABORTED: |
| 1533 | goto maybe_retry; |
| 1534 | case CHECK_CONDITION: |
| 1535 | rtn = scsi_check_sense(scmd); |
| 1536 | if (rtn == NEEDS_RETRY) |
| 1537 | goto maybe_retry; |
| 1538 | else if (rtn == TARGET_ERROR) { |
| 1539 | /* |
| 1540 | * Need to modify host byte to signal a |
| 1541 | * permanent target failure |
| 1542 | */ |
| 1543 | scmd->result |= (DID_TARGET_FAILURE << 16); |
| 1544 | rtn = SUCCESS; |
| 1545 | } |
| 1546 | /* if rtn == FAILED, we have no sense information; |
| 1547 | * returning FAILED will wake the error handler thread |
| 1548 | * to collect the sense and redo the decide |
| 1549 | * disposition */ |
| 1550 | return rtn; |
| 1551 | case CONDITION_GOOD: |
| 1552 | case INTERMEDIATE_GOOD: |
| 1553 | case INTERMEDIATE_C_GOOD: |
| 1554 | case ACA_ACTIVE: |
| 1555 | /* |
| 1556 | * who knows? FIXME(eric) |
| 1557 | */ |
| 1558 | return SUCCESS; |
| 1559 | |
| 1560 | case RESERVATION_CONFLICT: |
| 1561 | sdev_printk(KERN_INFO, scmd->device, |
| 1562 | "reservation conflict\n"); |
| 1563 | scmd->result |= (DID_NEXUS_FAILURE << 16); |
| 1564 | return SUCCESS; /* causes immediate i/o error */ |
| 1565 | default: |
| 1566 | return FAILED; |
| 1567 | } |
| 1568 | return FAILED; |
| 1569 | |
| 1570 | maybe_retry: |
| 1571 | |
| 1572 | /* we requeue for retry because the error was retryable, and |
| 1573 | * the request was not marked fast fail. Note that above, |
| 1574 | * even if the request is marked fast fail, we still requeue |
| 1575 | * for queue congestion conditions (QUEUE_FULL or BUSY) */ |
| 1576 | if ((++scmd->retries) <= scmd->allowed |
| 1577 | && !scsi_noretry_cmd(scmd)) { |
| 1578 | return NEEDS_RETRY; |
| 1579 | } else { |
| 1580 | /* |
| 1581 | * no more retries - report this one back to upper level. |
| 1582 | */ |
| 1583 | return SUCCESS; |
| 1584 | } |
| 1585 | } |
| 1586 | |
| 1587 | static void eh_lock_door_done(struct request *req, int uptodate) |
| 1588 | { |
| 1589 | __blk_put_request(req->q, req); |
| 1590 | } |
| 1591 | |
| 1592 | /** |
| 1593 | * scsi_eh_lock_door - Prevent medium removal for the specified device |
| 1594 | * @sdev: SCSI device to prevent medium removal |
| 1595 | * |
| 1596 | * Locking: |
| 1597 | * We must be called from process context. |
| 1598 | * |
| 1599 | * Notes: |
| 1600 | * We queue up an asynchronous "ALLOW MEDIUM REMOVAL" request on the |
| 1601 | * head of the devices request queue, and continue. |
| 1602 | */ |
| 1603 | static void scsi_eh_lock_door(struct scsi_device *sdev) |
| 1604 | { |
| 1605 | struct request *req; |
| 1606 | |
| 1607 | /* |
| 1608 | * blk_get_request with GFP_KERNEL (__GFP_WAIT) sleeps until a |
| 1609 | * request becomes available |
| 1610 | */ |
| 1611 | req = blk_get_request(sdev->request_queue, READ, GFP_KERNEL); |
| 1612 | |
| 1613 | req->cmd[0] = ALLOW_MEDIUM_REMOVAL; |
| 1614 | req->cmd[1] = 0; |
| 1615 | req->cmd[2] = 0; |
| 1616 | req->cmd[3] = 0; |
| 1617 | req->cmd[4] = SCSI_REMOVAL_PREVENT; |
| 1618 | req->cmd[5] = 0; |
| 1619 | |
| 1620 | req->cmd_len = COMMAND_SIZE(req->cmd[0]); |
| 1621 | |
| 1622 | req->cmd_type = REQ_TYPE_BLOCK_PC; |
| 1623 | req->cmd_flags |= REQ_QUIET; |
| 1624 | req->timeout = 10 * HZ; |
| 1625 | req->retries = 5; |
| 1626 | |
| 1627 | blk_execute_rq_nowait(req->q, NULL, req, 1, eh_lock_door_done); |
| 1628 | } |
| 1629 | |
| 1630 | /** |
| 1631 | * scsi_restart_operations - restart io operations to the specified host. |
| 1632 | * @shost: Host we are restarting. |
| 1633 | * |
| 1634 | * Notes: |
| 1635 | * When we entered the error handler, we blocked all further i/o to |
| 1636 | * this device. we need to 'reverse' this process. |
| 1637 | */ |
| 1638 | static void scsi_restart_operations(struct Scsi_Host *shost) |
| 1639 | { |
| 1640 | struct scsi_device *sdev; |
| 1641 | unsigned long flags; |
| 1642 | |
| 1643 | /* |
| 1644 | * If the door was locked, we need to insert a door lock request |
| 1645 | * onto the head of the SCSI request queue for the device. There |
| 1646 | * is no point trying to lock the door of an off-line device. |
| 1647 | */ |
| 1648 | shost_for_each_device(sdev, shost) { |
| 1649 | if (scsi_device_online(sdev) && sdev->locked) |
| 1650 | scsi_eh_lock_door(sdev); |
| 1651 | } |
| 1652 | |
| 1653 | /* |
| 1654 | * next free up anything directly waiting upon the host. this |
| 1655 | * will be requests for character device operations, and also for |
| 1656 | * ioctls to queued block devices. |
| 1657 | */ |
| 1658 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: waking up host to restart\n", |
| 1659 | __func__)); |
| 1660 | |
| 1661 | spin_lock_irqsave(shost->host_lock, flags); |
| 1662 | if (scsi_host_set_state(shost, SHOST_RUNNING)) |
| 1663 | if (scsi_host_set_state(shost, SHOST_CANCEL)) |
| 1664 | BUG_ON(scsi_host_set_state(shost, SHOST_DEL)); |
| 1665 | spin_unlock_irqrestore(shost->host_lock, flags); |
| 1666 | |
| 1667 | wake_up(&shost->host_wait); |
| 1668 | |
| 1669 | /* |
| 1670 | * finally we need to re-initiate requests that may be pending. we will |
| 1671 | * have had everything blocked while error handling is taking place, and |
| 1672 | * now that error recovery is done, we will need to ensure that these |
| 1673 | * requests are started. |
| 1674 | */ |
| 1675 | scsi_run_host_queues(shost); |
| 1676 | } |
| 1677 | |
| 1678 | /** |
| 1679 | * scsi_eh_ready_devs - check device ready state and recover if not. |
| 1680 | * @shost: host to be recovered. |
| 1681 | * @work_q: &list_head for pending commands. |
| 1682 | * @done_q: &list_head for processed commands. |
| 1683 | */ |
| 1684 | void scsi_eh_ready_devs(struct Scsi_Host *shost, |
| 1685 | struct list_head *work_q, |
| 1686 | struct list_head *done_q) |
| 1687 | { |
| 1688 | if (!scsi_eh_stu(shost, work_q, done_q)) |
| 1689 | if (!scsi_eh_bus_device_reset(shost, work_q, done_q)) |
| 1690 | if (!scsi_eh_target_reset(shost, work_q, done_q)) |
| 1691 | if (!scsi_eh_bus_reset(shost, work_q, done_q)) |
| 1692 | if (!scsi_eh_host_reset(work_q, done_q)) |
| 1693 | scsi_eh_offline_sdevs(work_q, |
| 1694 | done_q); |
| 1695 | } |
| 1696 | EXPORT_SYMBOL_GPL(scsi_eh_ready_devs); |
| 1697 | |
| 1698 | /** |
| 1699 | * scsi_eh_flush_done_q - finish processed commands or retry them. |
| 1700 | * @done_q: list_head of processed commands. |
| 1701 | */ |
| 1702 | void scsi_eh_flush_done_q(struct list_head *done_q) |
| 1703 | { |
| 1704 | struct scsi_cmnd *scmd, *next; |
| 1705 | |
| 1706 | list_for_each_entry_safe(scmd, next, done_q, eh_entry) { |
| 1707 | list_del_init(&scmd->eh_entry); |
| 1708 | if (scsi_device_online(scmd->device) && |
| 1709 | !scsi_noretry_cmd(scmd) && |
| 1710 | (++scmd->retries <= scmd->allowed)) { |
| 1711 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: flush" |
| 1712 | " retry cmd: %p\n", |
| 1713 | current->comm, |
| 1714 | scmd)); |
| 1715 | scsi_queue_insert(scmd, SCSI_MLQUEUE_EH_RETRY); |
| 1716 | } else { |
| 1717 | /* |
| 1718 | * If just we got sense for the device (called |
| 1719 | * scsi_eh_get_sense), scmd->result is already |
| 1720 | * set, do not set DRIVER_TIMEOUT. |
| 1721 | */ |
| 1722 | if (!scmd->result) |
| 1723 | scmd->result |= (DRIVER_TIMEOUT << 24); |
| 1724 | SCSI_LOG_ERROR_RECOVERY(3, printk("%s: flush finish" |
| 1725 | " cmd: %p\n", |
| 1726 | current->comm, scmd)); |
| 1727 | scsi_finish_command(scmd); |
| 1728 | } |
| 1729 | } |
| 1730 | } |
| 1731 | EXPORT_SYMBOL(scsi_eh_flush_done_q); |
| 1732 | |
| 1733 | /** |
| 1734 | * scsi_unjam_host - Attempt to fix a host which has a cmd that failed. |
| 1735 | * @shost: Host to unjam. |
| 1736 | * |
| 1737 | * Notes: |
| 1738 | * When we come in here, we *know* that all commands on the bus have |
| 1739 | * either completed, failed or timed out. we also know that no further |
| 1740 | * commands are being sent to the host, so things are relatively quiet |
| 1741 | * and we have freedom to fiddle with things as we wish. |
| 1742 | * |
| 1743 | * This is only the *default* implementation. it is possible for |
| 1744 | * individual drivers to supply their own version of this function, and |
| 1745 | * if the maintainer wishes to do this, it is strongly suggested that |
| 1746 | * this function be taken as a template and modified. this function |
| 1747 | * was designed to correctly handle problems for about 95% of the |
| 1748 | * different cases out there, and it should always provide at least a |
| 1749 | * reasonable amount of error recovery. |
| 1750 | * |
| 1751 | * Any command marked 'failed' or 'timeout' must eventually have |
| 1752 | * scsi_finish_cmd() called for it. we do all of the retry stuff |
| 1753 | * here, so when we restart the host after we return it should have an |
| 1754 | * empty queue. |
| 1755 | */ |
| 1756 | static void scsi_unjam_host(struct Scsi_Host *shost) |
| 1757 | { |
| 1758 | unsigned long flags; |
| 1759 | LIST_HEAD(eh_work_q); |
| 1760 | LIST_HEAD(eh_done_q); |
| 1761 | |
| 1762 | spin_lock_irqsave(shost->host_lock, flags); |
| 1763 | list_splice_init(&shost->eh_cmd_q, &eh_work_q); |
| 1764 | spin_unlock_irqrestore(shost->host_lock, flags); |
| 1765 | |
| 1766 | SCSI_LOG_ERROR_RECOVERY(1, scsi_eh_prt_fail_stats(shost, &eh_work_q)); |
| 1767 | |
| 1768 | if (!scsi_eh_get_sense(&eh_work_q, &eh_done_q)) |
| 1769 | if (!scsi_eh_abort_cmds(&eh_work_q, &eh_done_q)) |
| 1770 | scsi_eh_ready_devs(shost, &eh_work_q, &eh_done_q); |
| 1771 | |
| 1772 | scsi_eh_flush_done_q(&eh_done_q); |
| 1773 | } |
| 1774 | |
| 1775 | /** |
| 1776 | * scsi_error_handler - SCSI error handler thread |
| 1777 | * @data: Host for which we are running. |
| 1778 | * |
| 1779 | * Notes: |
| 1780 | * This is the main error handling loop. This is run as a kernel thread |
| 1781 | * for every SCSI host and handles all error handling activity. |
| 1782 | */ |
| 1783 | int scsi_error_handler(void *data) |
| 1784 | { |
| 1785 | struct Scsi_Host *shost = data; |
| 1786 | |
| 1787 | /* |
| 1788 | * We use TASK_INTERRUPTIBLE so that the thread is not |
| 1789 | * counted against the load average as a running process. |
| 1790 | * We never actually get interrupted because kthread_run |
| 1791 | * disables signal delivery for the created thread. |
| 1792 | */ |
| 1793 | set_current_state(TASK_INTERRUPTIBLE); |
| 1794 | while (!kthread_should_stop()) { |
| 1795 | if ((shost->host_failed == 0 && shost->host_eh_scheduled == 0) || |
| 1796 | shost->host_failed != shost->host_busy) { |
| 1797 | SCSI_LOG_ERROR_RECOVERY(1, |
| 1798 | printk("Error handler scsi_eh_%d sleeping\n", |
| 1799 | shost->host_no)); |
| 1800 | schedule(); |
| 1801 | set_current_state(TASK_INTERRUPTIBLE); |
| 1802 | continue; |
| 1803 | } |
| 1804 | |
| 1805 | __set_current_state(TASK_RUNNING); |
| 1806 | SCSI_LOG_ERROR_RECOVERY(1, |
| 1807 | printk("Error handler scsi_eh_%d waking up\n", |
| 1808 | shost->host_no)); |
| 1809 | |
| 1810 | /* |
| 1811 | * We have a host that is failing for some reason. Figure out |
| 1812 | * what we need to do to get it up and online again (if we can). |
| 1813 | * If we fail, we end up taking the thing offline. |
| 1814 | */ |
| 1815 | if (!shost->eh_noresume && scsi_autopm_get_host(shost) != 0) { |
| 1816 | SCSI_LOG_ERROR_RECOVERY(1, |
| 1817 | printk(KERN_ERR "Error handler scsi_eh_%d " |
| 1818 | "unable to autoresume\n", |
| 1819 | shost->host_no)); |
| 1820 | continue; |
| 1821 | } |
| 1822 | |
| 1823 | if (shost->transportt->eh_strategy_handler) |
| 1824 | shost->transportt->eh_strategy_handler(shost); |
| 1825 | else |
| 1826 | scsi_unjam_host(shost); |
| 1827 | |
| 1828 | /* |
| 1829 | * Note - if the above fails completely, the action is to take |
| 1830 | * individual devices offline and flush the queue of any |
| 1831 | * outstanding requests that may have been pending. When we |
| 1832 | * restart, we restart any I/O to any other devices on the bus |
| 1833 | * which are still online. |
| 1834 | */ |
| 1835 | scsi_restart_operations(shost); |
| 1836 | if (!shost->eh_noresume) |
| 1837 | scsi_autopm_put_host(shost); |
| 1838 | set_current_state(TASK_INTERRUPTIBLE); |
| 1839 | } |
| 1840 | __set_current_state(TASK_RUNNING); |
| 1841 | |
| 1842 | SCSI_LOG_ERROR_RECOVERY(1, |
| 1843 | printk("Error handler scsi_eh_%d exiting\n", shost->host_no)); |
| 1844 | shost->ehandler = NULL; |
| 1845 | return 0; |
| 1846 | } |
| 1847 | |
| 1848 | /* |
| 1849 | * Function: scsi_report_bus_reset() |
| 1850 | * |
| 1851 | * Purpose: Utility function used by low-level drivers to report that |
| 1852 | * they have observed a bus reset on the bus being handled. |
| 1853 | * |
| 1854 | * Arguments: shost - Host in question |
| 1855 | * channel - channel on which reset was observed. |
| 1856 | * |
| 1857 | * Returns: Nothing |
| 1858 | * |
| 1859 | * Lock status: Host lock must be held. |
| 1860 | * |
| 1861 | * Notes: This only needs to be called if the reset is one which |
| 1862 | * originates from an unknown location. Resets originated |
| 1863 | * by the mid-level itself don't need to call this, but there |
| 1864 | * should be no harm. |
| 1865 | * |
| 1866 | * The main purpose of this is to make sure that a CHECK_CONDITION |
| 1867 | * is properly treated. |
| 1868 | */ |
| 1869 | void scsi_report_bus_reset(struct Scsi_Host *shost, int channel) |
| 1870 | { |
| 1871 | struct scsi_device *sdev; |
| 1872 | |
| 1873 | __shost_for_each_device(sdev, shost) { |
| 1874 | if (channel == sdev_channel(sdev)) |
| 1875 | __scsi_report_device_reset(sdev, NULL); |
| 1876 | } |
| 1877 | } |
| 1878 | EXPORT_SYMBOL(scsi_report_bus_reset); |
| 1879 | |
| 1880 | /* |
| 1881 | * Function: scsi_report_device_reset() |
| 1882 | * |
| 1883 | * Purpose: Utility function used by low-level drivers to report that |
| 1884 | * they have observed a device reset on the device being handled. |
| 1885 | * |
| 1886 | * Arguments: shost - Host in question |
| 1887 | * channel - channel on which reset was observed |
| 1888 | * target - target on which reset was observed |
| 1889 | * |
| 1890 | * Returns: Nothing |
| 1891 | * |
| 1892 | * Lock status: Host lock must be held |
| 1893 | * |
| 1894 | * Notes: This only needs to be called if the reset is one which |
| 1895 | * originates from an unknown location. Resets originated |
| 1896 | * by the mid-level itself don't need to call this, but there |
| 1897 | * should be no harm. |
| 1898 | * |
| 1899 | * The main purpose of this is to make sure that a CHECK_CONDITION |
| 1900 | * is properly treated. |
| 1901 | */ |
| 1902 | void scsi_report_device_reset(struct Scsi_Host *shost, int channel, int target) |
| 1903 | { |
| 1904 | struct scsi_device *sdev; |
| 1905 | |
| 1906 | __shost_for_each_device(sdev, shost) { |
| 1907 | if (channel == sdev_channel(sdev) && |
| 1908 | target == sdev_id(sdev)) |
| 1909 | __scsi_report_device_reset(sdev, NULL); |
| 1910 | } |
| 1911 | } |
| 1912 | EXPORT_SYMBOL(scsi_report_device_reset); |
| 1913 | |
| 1914 | static void |
| 1915 | scsi_reset_provider_done_command(struct scsi_cmnd *scmd) |
| 1916 | { |
| 1917 | } |
| 1918 | |
| 1919 | /* |
| 1920 | * Function: scsi_reset_provider |
| 1921 | * |
| 1922 | * Purpose: Send requested reset to a bus or device at any phase. |
| 1923 | * |
| 1924 | * Arguments: device - device to send reset to |
| 1925 | * flag - reset type (see scsi.h) |
| 1926 | * |
| 1927 | * Returns: SUCCESS/FAILURE. |
| 1928 | * |
| 1929 | * Notes: This is used by the SCSI Generic driver to provide |
| 1930 | * Bus/Device reset capability. |
| 1931 | */ |
| 1932 | int |
| 1933 | scsi_reset_provider(struct scsi_device *dev, int flag) |
| 1934 | { |
| 1935 | struct scsi_cmnd *scmd; |
| 1936 | struct Scsi_Host *shost = dev->host; |
| 1937 | struct request req; |
| 1938 | unsigned long flags; |
| 1939 | int rtn; |
| 1940 | |
| 1941 | if (scsi_autopm_get_host(shost) < 0) |
| 1942 | return FAILED; |
| 1943 | |
| 1944 | scmd = scsi_get_command(dev, GFP_KERNEL); |
| 1945 | blk_rq_init(NULL, &req); |
| 1946 | scmd->request = &req; |
| 1947 | |
| 1948 | scmd->cmnd = req.cmd; |
| 1949 | |
| 1950 | scmd->scsi_done = scsi_reset_provider_done_command; |
| 1951 | memset(&scmd->sdb, 0, sizeof(scmd->sdb)); |
| 1952 | |
| 1953 | scmd->cmd_len = 0; |
| 1954 | |
| 1955 | scmd->sc_data_direction = DMA_BIDIRECTIONAL; |
| 1956 | |
| 1957 | spin_lock_irqsave(shost->host_lock, flags); |
| 1958 | shost->tmf_in_progress = 1; |
| 1959 | spin_unlock_irqrestore(shost->host_lock, flags); |
| 1960 | |
| 1961 | switch (flag) { |
| 1962 | case SCSI_TRY_RESET_DEVICE: |
| 1963 | rtn = scsi_try_bus_device_reset(scmd); |
| 1964 | if (rtn == SUCCESS) |
| 1965 | break; |
| 1966 | /* FALLTHROUGH */ |
| 1967 | case SCSI_TRY_RESET_TARGET: |
| 1968 | rtn = scsi_try_target_reset(scmd); |
| 1969 | if (rtn == SUCCESS) |
| 1970 | break; |
| 1971 | /* FALLTHROUGH */ |
| 1972 | case SCSI_TRY_RESET_BUS: |
| 1973 | rtn = scsi_try_bus_reset(scmd); |
| 1974 | if (rtn == SUCCESS) |
| 1975 | break; |
| 1976 | /* FALLTHROUGH */ |
| 1977 | case SCSI_TRY_RESET_HOST: |
| 1978 | rtn = scsi_try_host_reset(scmd); |
| 1979 | break; |
| 1980 | default: |
| 1981 | rtn = FAILED; |
| 1982 | } |
| 1983 | |
| 1984 | spin_lock_irqsave(shost->host_lock, flags); |
| 1985 | shost->tmf_in_progress = 0; |
| 1986 | spin_unlock_irqrestore(shost->host_lock, flags); |
| 1987 | |
| 1988 | /* |
| 1989 | * be sure to wake up anyone who was sleeping or had their queue |
| 1990 | * suspended while we performed the TMF. |
| 1991 | */ |
| 1992 | SCSI_LOG_ERROR_RECOVERY(3, |
| 1993 | printk("%s: waking up host to restart after TMF\n", |
| 1994 | __func__)); |
| 1995 | |
| 1996 | wake_up(&shost->host_wait); |
| 1997 | |
| 1998 | scsi_run_host_queues(shost); |
| 1999 | |
| 2000 | scsi_next_command(scmd); |
| 2001 | scsi_autopm_put_host(shost); |
| 2002 | return rtn; |
| 2003 | } |
| 2004 | EXPORT_SYMBOL(scsi_reset_provider); |
| 2005 | |
| 2006 | /** |
| 2007 | * scsi_normalize_sense - normalize main elements from either fixed or |
| 2008 | * descriptor sense data format into a common format. |
| 2009 | * |
| 2010 | * @sense_buffer: byte array containing sense data returned by device |
| 2011 | * @sb_len: number of valid bytes in sense_buffer |
| 2012 | * @sshdr: pointer to instance of structure that common |
| 2013 | * elements are written to. |
| 2014 | * |
| 2015 | * Notes: |
| 2016 | * The "main elements" from sense data are: response_code, sense_key, |
| 2017 | * asc, ascq and additional_length (only for descriptor format). |
| 2018 | * |
| 2019 | * Typically this function can be called after a device has |
| 2020 | * responded to a SCSI command with the CHECK_CONDITION status. |
| 2021 | * |
| 2022 | * Return value: |
| 2023 | * 1 if valid sense data information found, else 0; |
| 2024 | */ |
| 2025 | int scsi_normalize_sense(const u8 *sense_buffer, int sb_len, |
| 2026 | struct scsi_sense_hdr *sshdr) |
| 2027 | { |
| 2028 | if (!sense_buffer || !sb_len) |
| 2029 | return 0; |
| 2030 | |
| 2031 | memset(sshdr, 0, sizeof(struct scsi_sense_hdr)); |
| 2032 | |
| 2033 | sshdr->response_code = (sense_buffer[0] & 0x7f); |
| 2034 | |
| 2035 | if (!scsi_sense_valid(sshdr)) |
| 2036 | return 0; |
| 2037 | |
| 2038 | if (sshdr->response_code >= 0x72) { |
| 2039 | /* |
| 2040 | * descriptor format |
| 2041 | */ |
| 2042 | if (sb_len > 1) |
| 2043 | sshdr->sense_key = (sense_buffer[1] & 0xf); |
| 2044 | if (sb_len > 2) |
| 2045 | sshdr->asc = sense_buffer[2]; |
| 2046 | if (sb_len > 3) |
| 2047 | sshdr->ascq = sense_buffer[3]; |
| 2048 | if (sb_len > 7) |
| 2049 | sshdr->additional_length = sense_buffer[7]; |
| 2050 | } else { |
| 2051 | /* |
| 2052 | * fixed format |
| 2053 | */ |
| 2054 | if (sb_len > 2) |
| 2055 | sshdr->sense_key = (sense_buffer[2] & 0xf); |
| 2056 | if (sb_len > 7) { |
| 2057 | sb_len = (sb_len < (sense_buffer[7] + 8)) ? |
| 2058 | sb_len : (sense_buffer[7] + 8); |
| 2059 | if (sb_len > 12) |
| 2060 | sshdr->asc = sense_buffer[12]; |
| 2061 | if (sb_len > 13) |
| 2062 | sshdr->ascq = sense_buffer[13]; |
| 2063 | } |
| 2064 | } |
| 2065 | |
| 2066 | return 1; |
| 2067 | } |
| 2068 | EXPORT_SYMBOL(scsi_normalize_sense); |
| 2069 | |
| 2070 | int scsi_command_normalize_sense(struct scsi_cmnd *cmd, |
| 2071 | struct scsi_sense_hdr *sshdr) |
| 2072 | { |
| 2073 | return scsi_normalize_sense(cmd->sense_buffer, |
| 2074 | SCSI_SENSE_BUFFERSIZE, sshdr); |
| 2075 | } |
| 2076 | EXPORT_SYMBOL(scsi_command_normalize_sense); |
| 2077 | |
| 2078 | /** |
| 2079 | * scsi_sense_desc_find - search for a given descriptor type in descriptor sense data format. |
| 2080 | * @sense_buffer: byte array of descriptor format sense data |
| 2081 | * @sb_len: number of valid bytes in sense_buffer |
| 2082 | * @desc_type: value of descriptor type to find |
| 2083 | * (e.g. 0 -> information) |
| 2084 | * |
| 2085 | * Notes: |
| 2086 | * only valid when sense data is in descriptor format |
| 2087 | * |
| 2088 | * Return value: |
| 2089 | * pointer to start of (first) descriptor if found else NULL |
| 2090 | */ |
| 2091 | const u8 * scsi_sense_desc_find(const u8 * sense_buffer, int sb_len, |
| 2092 | int desc_type) |
| 2093 | { |
| 2094 | int add_sen_len, add_len, desc_len, k; |
| 2095 | const u8 * descp; |
| 2096 | |
| 2097 | if ((sb_len < 8) || (0 == (add_sen_len = sense_buffer[7]))) |
| 2098 | return NULL; |
| 2099 | if ((sense_buffer[0] < 0x72) || (sense_buffer[0] > 0x73)) |
| 2100 | return NULL; |
| 2101 | add_sen_len = (add_sen_len < (sb_len - 8)) ? |
| 2102 | add_sen_len : (sb_len - 8); |
| 2103 | descp = &sense_buffer[8]; |
| 2104 | for (desc_len = 0, k = 0; k < add_sen_len; k += desc_len) { |
| 2105 | descp += desc_len; |
| 2106 | add_len = (k < (add_sen_len - 1)) ? descp[1]: -1; |
| 2107 | desc_len = add_len + 2; |
| 2108 | if (descp[0] == desc_type) |
| 2109 | return descp; |
| 2110 | if (add_len < 0) // short descriptor ?? |
| 2111 | break; |
| 2112 | } |
| 2113 | return NULL; |
| 2114 | } |
| 2115 | EXPORT_SYMBOL(scsi_sense_desc_find); |
| 2116 | |
| 2117 | /** |
| 2118 | * scsi_get_sense_info_fld - get information field from sense data (either fixed or descriptor format) |
| 2119 | * @sense_buffer: byte array of sense data |
| 2120 | * @sb_len: number of valid bytes in sense_buffer |
| 2121 | * @info_out: pointer to 64 integer where 8 or 4 byte information |
| 2122 | * field will be placed if found. |
| 2123 | * |
| 2124 | * Return value: |
| 2125 | * 1 if information field found, 0 if not found. |
| 2126 | */ |
| 2127 | int scsi_get_sense_info_fld(const u8 * sense_buffer, int sb_len, |
| 2128 | u64 * info_out) |
| 2129 | { |
| 2130 | int j; |
| 2131 | const u8 * ucp; |
| 2132 | u64 ull; |
| 2133 | |
| 2134 | if (sb_len < 7) |
| 2135 | return 0; |
| 2136 | switch (sense_buffer[0] & 0x7f) { |
| 2137 | case 0x70: |
| 2138 | case 0x71: |
| 2139 | if (sense_buffer[0] & 0x80) { |
| 2140 | *info_out = (sense_buffer[3] << 24) + |
| 2141 | (sense_buffer[4] << 16) + |
| 2142 | (sense_buffer[5] << 8) + sense_buffer[6]; |
| 2143 | return 1; |
| 2144 | } else |
| 2145 | return 0; |
| 2146 | case 0x72: |
| 2147 | case 0x73: |
| 2148 | ucp = scsi_sense_desc_find(sense_buffer, sb_len, |
| 2149 | 0 /* info desc */); |
| 2150 | if (ucp && (0xa == ucp[1])) { |
| 2151 | ull = 0; |
| 2152 | for (j = 0; j < 8; ++j) { |
| 2153 | if (j > 0) |
| 2154 | ull <<= 8; |
| 2155 | ull |= ucp[4 + j]; |
| 2156 | } |
| 2157 | *info_out = ull; |
| 2158 | return 1; |
| 2159 | } else |
| 2160 | return 0; |
| 2161 | default: |
| 2162 | return 0; |
| 2163 | } |
| 2164 | } |
| 2165 | EXPORT_SYMBOL(scsi_get_sense_info_fld); |
| 2166 | |
| 2167 | /** |
| 2168 | * scsi_build_sense_buffer - build sense data in a buffer |
| 2169 | * @desc: Sense format (non zero == descriptor format, |
| 2170 | * 0 == fixed format) |
| 2171 | * @buf: Where to build sense data |
| 2172 | * @key: Sense key |
| 2173 | * @asc: Additional sense code |
| 2174 | * @ascq: Additional sense code qualifier |
| 2175 | * |
| 2176 | **/ |
| 2177 | void scsi_build_sense_buffer(int desc, u8 *buf, u8 key, u8 asc, u8 ascq) |
| 2178 | { |
| 2179 | if (desc) { |
| 2180 | buf[0] = 0x72; /* descriptor, current */ |
| 2181 | buf[1] = key; |
| 2182 | buf[2] = asc; |
| 2183 | buf[3] = ascq; |
| 2184 | buf[7] = 0; |
| 2185 | } else { |
| 2186 | buf[0] = 0x70; /* fixed, current */ |
| 2187 | buf[2] = key; |
| 2188 | buf[7] = 0xa; |
| 2189 | buf[12] = asc; |
| 2190 | buf[13] = ascq; |
| 2191 | } |
| 2192 | } |
| 2193 | EXPORT_SYMBOL(scsi_build_sense_buffer); |