1 // SPDX-License-Identifier: GPL-2.0-only
3 * Copyright (C) 1999 Eric Youngdale
4 * Copyright (C) 2014 Christoph Hellwig
6 * SCSI queueing library.
7 * Initial versions: Eric Youngdale (eric@andante.org).
8 * Based upon conversations with large numbers
9 * of people at Linux Expo.
12 #include <linux/bio.h>
13 #include <linux/bitops.h>
14 #include <linux/blkdev.h>
15 #include <linux/completion.h>
16 #include <linux/kernel.h>
17 #include <linux/export.h>
18 #include <linux/init.h>
19 #include <linux/pci.h>
20 #include <linux/delay.h>
21 #include <linux/hardirq.h>
22 #include <linux/scatterlist.h>
23 #include <linux/blk-mq.h>
24 #include <linux/blk-integrity.h>
25 #include <linux/ratelimit.h>
26 #include <asm/unaligned.h>
28 #include <scsi/scsi.h>
29 #include <scsi/scsi_cmnd.h>
30 #include <scsi/scsi_dbg.h>
31 #include <scsi/scsi_device.h>
32 #include <scsi/scsi_driver.h>
33 #include <scsi/scsi_eh.h>
34 #include <scsi/scsi_host.h>
35 #include <scsi/scsi_transport.h> /* __scsi_init_queue() */
36 #include <scsi/scsi_dh.h>
38 #include <trace/events/scsi.h>
40 #include "scsi_debugfs.h"
41 #include "scsi_priv.h"
42 #include "scsi_logging.h"
45 * Size of integrity metadata is usually small, 1 inline sg should
48 #ifdef CONFIG_ARCH_NO_SG_CHAIN
49 #define SCSI_INLINE_PROT_SG_CNT 0
50 #define SCSI_INLINE_SG_CNT 0
52 #define SCSI_INLINE_PROT_SG_CNT 1
53 #define SCSI_INLINE_SG_CNT 2
56 static struct kmem_cache *scsi_sense_cache;
57 static DEFINE_MUTEX(scsi_sense_cache_mutex);
59 static void scsi_mq_uninit_cmd(struct scsi_cmnd *cmd);
61 int scsi_init_sense_cache(struct Scsi_Host *shost)
65 mutex_lock(&scsi_sense_cache_mutex);
66 if (!scsi_sense_cache) {
68 kmem_cache_create_usercopy("scsi_sense_cache",
69 SCSI_SENSE_BUFFERSIZE, 0, SLAB_HWCACHE_ALIGN,
70 0, SCSI_SENSE_BUFFERSIZE, NULL);
71 if (!scsi_sense_cache)
74 mutex_unlock(&scsi_sense_cache_mutex);
79 scsi_set_blocked(struct scsi_cmnd *cmd, int reason)
81 struct Scsi_Host *host = cmd->device->host;
82 struct scsi_device *device = cmd->device;
83 struct scsi_target *starget = scsi_target(device);
86 * Set the appropriate busy bit for the device/host.
88 * If the host/device isn't busy, assume that something actually
89 * completed, and that we should be able to queue a command now.
91 * Note that the prior mid-layer assumption that any host could
92 * always queue at least one command is now broken. The mid-layer
93 * will implement a user specifiable stall (see
94 * scsi_host.max_host_blocked and scsi_device.max_device_blocked)
95 * if a command is requeued with no other commands outstanding
96 * either for the device or for the host.
99 case SCSI_MLQUEUE_HOST_BUSY:
100 atomic_set(&host->host_blocked, host->max_host_blocked);
102 case SCSI_MLQUEUE_DEVICE_BUSY:
103 case SCSI_MLQUEUE_EH_RETRY:
104 atomic_set(&device->device_blocked,
105 device->max_device_blocked);
107 case SCSI_MLQUEUE_TARGET_BUSY:
108 atomic_set(&starget->target_blocked,
109 starget->max_target_blocked);
114 static void scsi_mq_requeue_cmd(struct scsi_cmnd *cmd, unsigned long msecs)
116 struct request *rq = scsi_cmd_to_rq(cmd);
118 if (rq->rq_flags & RQF_DONTPREP) {
119 rq->rq_flags &= ~RQF_DONTPREP;
120 scsi_mq_uninit_cmd(cmd);
125 blk_mq_requeue_request(rq, false);
126 if (!scsi_host_in_recovery(cmd->device->host))
127 blk_mq_delay_kick_requeue_list(rq->q, msecs);
131 * __scsi_queue_insert - private queue insertion
132 * @cmd: The SCSI command being requeued
133 * @reason: The reason for the requeue
134 * @unbusy: Whether the queue should be unbusied
136 * This is a private queue insertion. The public interface
137 * scsi_queue_insert() always assumes the queue should be unbusied
138 * because it's always called before the completion. This function is
139 * for a requeue after completion, which should only occur in this
142 static void __scsi_queue_insert(struct scsi_cmnd *cmd, int reason, bool unbusy)
144 struct scsi_device *device = cmd->device;
146 SCSI_LOG_MLQUEUE(1, scmd_printk(KERN_INFO, cmd,
147 "Inserting command %p into mlqueue\n", cmd));
149 scsi_set_blocked(cmd, reason);
152 * Decrement the counters, since these commands are no longer
153 * active on the host/device.
156 scsi_device_unbusy(device, cmd);
159 * Requeue this command. It will go before all other commands
160 * that are already in the queue. Schedule requeue work under
161 * lock such that the kblockd_schedule_work() call happens
162 * before blk_mq_destroy_queue() finishes.
166 blk_mq_requeue_request(scsi_cmd_to_rq(cmd),
167 !scsi_host_in_recovery(cmd->device->host));
171 * scsi_queue_insert - Reinsert a command in the queue.
172 * @cmd: command that we are adding to queue.
173 * @reason: why we are inserting command to queue.
175 * We do this for one of two cases. Either the host is busy and it cannot accept
176 * any more commands for the time being, or the device returned QUEUE_FULL and
177 * can accept no more commands.
179 * Context: This could be called either from an interrupt context or a normal
182 void scsi_queue_insert(struct scsi_cmnd *cmd, int reason)
184 __scsi_queue_insert(cmd, reason, true);
188 * scsi_execute_cmd - insert request and wait for the result
191 * @opf: block layer request cmd_flags
192 * @buffer: data buffer
193 * @bufflen: len of buffer
194 * @timeout: request timeout in HZ
195 * @retries: number of times to retry request
196 * @args: Optional args. See struct definition for field descriptions
198 * Returns the scsi_cmnd result field if a command was executed, or a negative
199 * Linux error code if we didn't get that far.
201 int scsi_execute_cmd(struct scsi_device *sdev, const unsigned char *cmd,
202 blk_opf_t opf, void *buffer, unsigned int bufflen,
203 int timeout, int retries,
204 const struct scsi_exec_args *args)
206 static const struct scsi_exec_args default_args;
208 struct scsi_cmnd *scmd;
212 args = &default_args;
213 else if (WARN_ON_ONCE(args->sense &&
214 args->sense_len != SCSI_SENSE_BUFFERSIZE))
217 req = scsi_alloc_request(sdev->request_queue, opf, args->req_flags);
222 ret = blk_rq_map_kern(sdev->request_queue, req,
223 buffer, bufflen, GFP_NOIO);
227 scmd = blk_mq_rq_to_pdu(req);
228 scmd->cmd_len = COMMAND_SIZE(cmd[0]);
229 memcpy(scmd->cmnd, cmd, scmd->cmd_len);
230 scmd->allowed = retries;
231 scmd->flags |= args->scmd_flags;
232 req->timeout = timeout;
233 req->rq_flags |= RQF_QUIET;
236 * head injection *required* here otherwise quiesce won't work
238 blk_execute_rq(req, true);
241 * Some devices (USB mass-storage in particular) may transfer
242 * garbage data together with a residue indicating that the data
243 * is invalid. Prevent the garbage from being misinterpreted
244 * and prevent security leaks by zeroing out the excess data.
246 if (unlikely(scmd->resid_len > 0 && scmd->resid_len <= bufflen))
247 memset(buffer + bufflen - scmd->resid_len, 0, scmd->resid_len);
250 *args->resid = scmd->resid_len;
252 memcpy(args->sense, scmd->sense_buffer, SCSI_SENSE_BUFFERSIZE);
254 scsi_normalize_sense(scmd->sense_buffer, scmd->sense_len,
259 blk_mq_free_request(req);
263 EXPORT_SYMBOL(scsi_execute_cmd);
266 * Wake up the error handler if necessary. Avoid as follows that the error
267 * handler is not woken up if host in-flight requests number ==
268 * shost->host_failed: use call_rcu() in scsi_eh_scmd_add() in combination
269 * with an RCU read lock in this function to ensure that this function in
270 * its entirety either finishes before scsi_eh_scmd_add() increases the
271 * host_failed counter or that it notices the shost state change made by
272 * scsi_eh_scmd_add().
274 static void scsi_dec_host_busy(struct Scsi_Host *shost, struct scsi_cmnd *cmd)
279 __clear_bit(SCMD_STATE_INFLIGHT, &cmd->state);
280 if (unlikely(scsi_host_in_recovery(shost))) {
281 spin_lock_irqsave(shost->host_lock, flags);
282 if (shost->host_failed || shost->host_eh_scheduled)
283 scsi_eh_wakeup(shost);
284 spin_unlock_irqrestore(shost->host_lock, flags);
289 void scsi_device_unbusy(struct scsi_device *sdev, struct scsi_cmnd *cmd)
291 struct Scsi_Host *shost = sdev->host;
292 struct scsi_target *starget = scsi_target(sdev);
294 scsi_dec_host_busy(shost, cmd);
296 if (starget->can_queue > 0)
297 atomic_dec(&starget->target_busy);
299 sbitmap_put(&sdev->budget_map, cmd->budget_token);
300 cmd->budget_token = -1;
304 * Kick the queue of SCSI device @sdev if @sdev != current_sdev. Called with
305 * interrupts disabled.
307 static void scsi_kick_sdev_queue(struct scsi_device *sdev, void *data)
309 struct scsi_device *current_sdev = data;
311 if (sdev != current_sdev)
312 blk_mq_run_hw_queues(sdev->request_queue, true);
316 * Called for single_lun devices on IO completion. Clear starget_sdev_user,
317 * and call blk_run_queue for all the scsi_devices on the target -
318 * including current_sdev first.
320 * Called with *no* scsi locks held.
322 static void scsi_single_lun_run(struct scsi_device *current_sdev)
324 struct Scsi_Host *shost = current_sdev->host;
325 struct scsi_target *starget = scsi_target(current_sdev);
328 spin_lock_irqsave(shost->host_lock, flags);
329 starget->starget_sdev_user = NULL;
330 spin_unlock_irqrestore(shost->host_lock, flags);
333 * Call blk_run_queue for all LUNs on the target, starting with
334 * current_sdev. We race with others (to set starget_sdev_user),
335 * but in most cases, we will be first. Ideally, each LU on the
336 * target would get some limited time or requests on the target.
338 blk_mq_run_hw_queues(current_sdev->request_queue,
339 shost->queuecommand_may_block);
341 spin_lock_irqsave(shost->host_lock, flags);
342 if (!starget->starget_sdev_user)
343 __starget_for_each_device(starget, current_sdev,
344 scsi_kick_sdev_queue);
345 spin_unlock_irqrestore(shost->host_lock, flags);
348 static inline bool scsi_device_is_busy(struct scsi_device *sdev)
350 if (scsi_device_busy(sdev) >= sdev->queue_depth)
352 if (atomic_read(&sdev->device_blocked) > 0)
357 static inline bool scsi_target_is_busy(struct scsi_target *starget)
359 if (starget->can_queue > 0) {
360 if (atomic_read(&starget->target_busy) >= starget->can_queue)
362 if (atomic_read(&starget->target_blocked) > 0)
368 static inline bool scsi_host_is_busy(struct Scsi_Host *shost)
370 if (atomic_read(&shost->host_blocked) > 0)
372 if (shost->host_self_blocked)
377 static void scsi_starved_list_run(struct Scsi_Host *shost)
379 LIST_HEAD(starved_list);
380 struct scsi_device *sdev;
383 spin_lock_irqsave(shost->host_lock, flags);
384 list_splice_init(&shost->starved_list, &starved_list);
386 while (!list_empty(&starved_list)) {
387 struct request_queue *slq;
390 * As long as shost is accepting commands and we have
391 * starved queues, call blk_run_queue. scsi_request_fn
392 * drops the queue_lock and can add us back to the
395 * host_lock protects the starved_list and starved_entry.
396 * scsi_request_fn must get the host_lock before checking
397 * or modifying starved_list or starved_entry.
399 if (scsi_host_is_busy(shost))
402 sdev = list_entry(starved_list.next,
403 struct scsi_device, starved_entry);
404 list_del_init(&sdev->starved_entry);
405 if (scsi_target_is_busy(scsi_target(sdev))) {
406 list_move_tail(&sdev->starved_entry,
407 &shost->starved_list);
412 * Once we drop the host lock, a racing scsi_remove_device()
413 * call may remove the sdev from the starved list and destroy
414 * it and the queue. Mitigate by taking a reference to the
415 * queue and never touching the sdev again after we drop the
416 * host lock. Note: if __scsi_remove_device() invokes
417 * blk_mq_destroy_queue() before the queue is run from this
418 * function then blk_run_queue() will return immediately since
419 * blk_mq_destroy_queue() marks the queue with QUEUE_FLAG_DYING.
421 slq = sdev->request_queue;
422 if (!blk_get_queue(slq))
424 spin_unlock_irqrestore(shost->host_lock, flags);
426 blk_mq_run_hw_queues(slq, false);
429 spin_lock_irqsave(shost->host_lock, flags);
431 /* put any unprocessed entries back */
432 list_splice(&starved_list, &shost->starved_list);
433 spin_unlock_irqrestore(shost->host_lock, flags);
437 * scsi_run_queue - Select a proper request queue to serve next.
438 * @q: last request's queue
440 * The previous command was completely finished, start a new one if possible.
442 static void scsi_run_queue(struct request_queue *q)
444 struct scsi_device *sdev = q->queuedata;
446 if (scsi_target(sdev)->single_lun)
447 scsi_single_lun_run(sdev);
448 if (!list_empty(&sdev->host->starved_list))
449 scsi_starved_list_run(sdev->host);
451 /* Note: blk_mq_kick_requeue_list() runs the queue asynchronously. */
452 blk_mq_kick_requeue_list(q);
455 void scsi_requeue_run_queue(struct work_struct *work)
457 struct scsi_device *sdev;
458 struct request_queue *q;
460 sdev = container_of(work, struct scsi_device, requeue_work);
461 q = sdev->request_queue;
465 void scsi_run_host_queues(struct Scsi_Host *shost)
467 struct scsi_device *sdev;
469 shost_for_each_device(sdev, shost)
470 scsi_run_queue(sdev->request_queue);
473 static void scsi_uninit_cmd(struct scsi_cmnd *cmd)
475 if (!blk_rq_is_passthrough(scsi_cmd_to_rq(cmd))) {
476 struct scsi_driver *drv = scsi_cmd_to_driver(cmd);
478 if (drv->uninit_command)
479 drv->uninit_command(cmd);
483 void scsi_free_sgtables(struct scsi_cmnd *cmd)
485 if (cmd->sdb.table.nents)
486 sg_free_table_chained(&cmd->sdb.table,
488 if (scsi_prot_sg_count(cmd))
489 sg_free_table_chained(&cmd->prot_sdb->table,
490 SCSI_INLINE_PROT_SG_CNT);
492 EXPORT_SYMBOL_GPL(scsi_free_sgtables);
494 static void scsi_mq_uninit_cmd(struct scsi_cmnd *cmd)
496 scsi_free_sgtables(cmd);
497 scsi_uninit_cmd(cmd);
500 static void scsi_run_queue_async(struct scsi_device *sdev)
502 if (scsi_host_in_recovery(sdev->host))
505 if (scsi_target(sdev)->single_lun ||
506 !list_empty(&sdev->host->starved_list)) {
507 kblockd_schedule_work(&sdev->requeue_work);
510 * smp_mb() present in sbitmap_queue_clear() or implied in
511 * .end_io is for ordering writing .device_busy in
512 * scsi_device_unbusy() and reading sdev->restarts.
514 int old = atomic_read(&sdev->restarts);
517 * ->restarts has to be kept as non-zero if new budget
520 * No need to run queue when either another re-run
521 * queue wins in updating ->restarts or a new budget
524 if (old && atomic_cmpxchg(&sdev->restarts, old, 0) == old)
525 blk_mq_run_hw_queues(sdev->request_queue, true);
529 /* Returns false when no more bytes to process, true if there are more */
530 static bool scsi_end_request(struct request *req, blk_status_t error,
533 struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req);
534 struct scsi_device *sdev = cmd->device;
535 struct request_queue *q = sdev->request_queue;
537 if (blk_update_request(req, error, bytes))
541 if (blk_queue_add_random(q))
542 add_disk_randomness(req->q->disk);
544 if (!blk_rq_is_passthrough(req)) {
545 WARN_ON_ONCE(!(cmd->flags & SCMD_INITIALIZED));
546 cmd->flags &= ~SCMD_INITIALIZED;
550 * Calling rcu_barrier() is not necessary here because the
551 * SCSI error handler guarantees that the function called by
552 * call_rcu() has been called before scsi_end_request() is
555 destroy_rcu_head(&cmd->rcu);
558 * In the MQ case the command gets freed by __blk_mq_end_request,
559 * so we have to do all cleanup that depends on it earlier.
561 * We also can't kick the queues from irq context, so we
562 * will have to defer it to a workqueue.
564 scsi_mq_uninit_cmd(cmd);
567 * queue is still alive, so grab the ref for preventing it
568 * from being cleaned up during running queue.
570 percpu_ref_get(&q->q_usage_counter);
572 __blk_mq_end_request(req, error);
574 scsi_run_queue_async(sdev);
576 percpu_ref_put(&q->q_usage_counter);
581 * scsi_result_to_blk_status - translate a SCSI result code into blk_status_t
582 * @result: scsi error code
584 * Translate a SCSI result code into a blk_status_t value.
586 static blk_status_t scsi_result_to_blk_status(int result)
589 * Check the scsi-ml byte first in case we converted a host or status
592 switch (scsi_ml_byte(result)) {
595 case SCSIML_STAT_RESV_CONFLICT:
596 return BLK_STS_RESV_CONFLICT;
597 case SCSIML_STAT_NOSPC:
598 return BLK_STS_NOSPC;
599 case SCSIML_STAT_MED_ERROR:
600 return BLK_STS_MEDIUM;
601 case SCSIML_STAT_TGT_FAILURE:
602 return BLK_STS_TARGET;
603 case SCSIML_STAT_DL_TIMEOUT:
604 return BLK_STS_DURATION_LIMIT;
607 switch (host_byte(result)) {
609 if (scsi_status_is_good(result))
611 return BLK_STS_IOERR;
612 case DID_TRANSPORT_FAILFAST:
613 case DID_TRANSPORT_MARGINAL:
614 return BLK_STS_TRANSPORT;
616 return BLK_STS_IOERR;
621 * scsi_rq_err_bytes - determine number of bytes till the next failure boundary
622 * @rq: request to examine
625 * A request could be merge of IOs which require different failure
626 * handling. This function determines the number of bytes which
627 * can be failed from the beginning of the request without
628 * crossing into area which need to be retried further.
631 * The number of bytes to fail.
633 static unsigned int scsi_rq_err_bytes(const struct request *rq)
635 blk_opf_t ff = rq->cmd_flags & REQ_FAILFAST_MASK;
636 unsigned int bytes = 0;
639 if (!(rq->rq_flags & RQF_MIXED_MERGE))
640 return blk_rq_bytes(rq);
643 * Currently the only 'mixing' which can happen is between
644 * different fastfail types. We can safely fail portions
645 * which have all the failfast bits that the first one has -
646 * the ones which are at least as eager to fail as the first
649 for (bio = rq->bio; bio; bio = bio->bi_next) {
650 if ((bio->bi_opf & ff) != ff)
652 bytes += bio->bi_iter.bi_size;
655 /* this could lead to infinite loop */
656 BUG_ON(blk_rq_bytes(rq) && !bytes);
660 static bool scsi_cmd_runtime_exceeced(struct scsi_cmnd *cmd)
662 struct request *req = scsi_cmd_to_rq(cmd);
663 unsigned long wait_for;
665 if (cmd->allowed == SCSI_CMD_RETRIES_NO_LIMIT)
668 wait_for = (cmd->allowed + 1) * req->timeout;
669 if (time_before(cmd->jiffies_at_alloc + wait_for, jiffies)) {
670 scmd_printk(KERN_ERR, cmd, "timing out command, waited %lus\n",
678 * When ALUA transition state is returned, reprep the cmd to
679 * use the ALUA handler's transition timeout. Delay the reprep
680 * 1 sec to avoid aggressive retries of the target in that
683 #define ALUA_TRANSITION_REPREP_DELAY 1000
685 /* Helper for scsi_io_completion() when special action required. */
686 static void scsi_io_completion_action(struct scsi_cmnd *cmd, int result)
688 struct request *req = scsi_cmd_to_rq(cmd);
690 enum {ACTION_FAIL, ACTION_REPREP, ACTION_DELAYED_REPREP,
691 ACTION_RETRY, ACTION_DELAYED_RETRY} action;
692 struct scsi_sense_hdr sshdr;
694 bool sense_current = true; /* false implies "deferred sense" */
695 blk_status_t blk_stat;
697 sense_valid = scsi_command_normalize_sense(cmd, &sshdr);
699 sense_current = !scsi_sense_is_deferred(&sshdr);
701 blk_stat = scsi_result_to_blk_status(result);
703 if (host_byte(result) == DID_RESET) {
704 /* Third party bus reset or reset for error recovery
705 * reasons. Just retry the command and see what
708 action = ACTION_RETRY;
709 } else if (sense_valid && sense_current) {
710 switch (sshdr.sense_key) {
712 if (cmd->device->removable) {
713 /* Detected disc change. Set a bit
714 * and quietly refuse further access.
716 cmd->device->changed = 1;
717 action = ACTION_FAIL;
719 /* Must have been a power glitch, or a
720 * bus reset. Could not have been a
721 * media change, so we just retry the
722 * command and see what happens.
724 action = ACTION_RETRY;
727 case ILLEGAL_REQUEST:
728 /* If we had an ILLEGAL REQUEST returned, then
729 * we may have performed an unsupported
730 * command. The only thing this should be
731 * would be a ten byte read where only a six
732 * byte read was supported. Also, on a system
733 * where READ CAPACITY failed, we may have
734 * read past the end of the disk.
736 if ((cmd->device->use_10_for_rw &&
737 sshdr.asc == 0x20 && sshdr.ascq == 0x00) &&
738 (cmd->cmnd[0] == READ_10 ||
739 cmd->cmnd[0] == WRITE_10)) {
740 /* This will issue a new 6-byte command. */
741 cmd->device->use_10_for_rw = 0;
742 action = ACTION_REPREP;
743 } else if (sshdr.asc == 0x10) /* DIX */ {
744 action = ACTION_FAIL;
745 blk_stat = BLK_STS_PROTECTION;
746 /* INVALID COMMAND OPCODE or INVALID FIELD IN CDB */
747 } else if (sshdr.asc == 0x20 || sshdr.asc == 0x24) {
748 action = ACTION_FAIL;
749 blk_stat = BLK_STS_TARGET;
751 action = ACTION_FAIL;
753 case ABORTED_COMMAND:
754 action = ACTION_FAIL;
755 if (sshdr.asc == 0x10) /* DIF */
756 blk_stat = BLK_STS_PROTECTION;
759 /* If the device is in the process of becoming
760 * ready, or has a temporary blockage, retry.
762 if (sshdr.asc == 0x04) {
763 switch (sshdr.ascq) {
764 case 0x01: /* becoming ready */
765 case 0x04: /* format in progress */
766 case 0x05: /* rebuild in progress */
767 case 0x06: /* recalculation in progress */
768 case 0x07: /* operation in progress */
769 case 0x08: /* Long write in progress */
770 case 0x09: /* self test in progress */
771 case 0x11: /* notify (enable spinup) required */
772 case 0x14: /* space allocation in progress */
773 case 0x1a: /* start stop unit in progress */
774 case 0x1b: /* sanitize in progress */
775 case 0x1d: /* configuration in progress */
776 case 0x24: /* depopulation in progress */
777 case 0x25: /* depopulation restore in progress */
778 action = ACTION_DELAYED_RETRY;
780 case 0x0a: /* ALUA state transition */
781 action = ACTION_DELAYED_REPREP;
784 action = ACTION_FAIL;
788 action = ACTION_FAIL;
790 case VOLUME_OVERFLOW:
791 /* See SSC3rXX or current. */
792 action = ACTION_FAIL;
795 action = ACTION_FAIL;
796 if ((sshdr.asc == 0x0C && sshdr.ascq == 0x12) ||
797 (sshdr.asc == 0x55 &&
798 (sshdr.ascq == 0x0E || sshdr.ascq == 0x0F))) {
799 /* Insufficient zone resources */
800 blk_stat = BLK_STS_ZONE_OPEN_RESOURCE;
806 action = ACTION_FAIL;
810 action = ACTION_FAIL;
812 if (action != ACTION_FAIL && scsi_cmd_runtime_exceeced(cmd))
813 action = ACTION_FAIL;
817 /* Give up and fail the remainder of the request */
818 if (!(req->rq_flags & RQF_QUIET)) {
819 static DEFINE_RATELIMIT_STATE(_rs,
820 DEFAULT_RATELIMIT_INTERVAL,
821 DEFAULT_RATELIMIT_BURST);
823 if (unlikely(scsi_logging_level))
825 SCSI_LOG_LEVEL(SCSI_LOG_MLCOMPLETE_SHIFT,
826 SCSI_LOG_MLCOMPLETE_BITS);
829 * if logging is enabled the failure will be printed
830 * in scsi_log_completion(), so avoid duplicate messages
832 if (!level && __ratelimit(&_rs)) {
833 scsi_print_result(cmd, NULL, FAILED);
835 scsi_print_sense(cmd);
836 scsi_print_command(cmd);
839 if (!scsi_end_request(req, blk_stat, scsi_rq_err_bytes(req)))
843 scsi_mq_requeue_cmd(cmd, 0);
845 case ACTION_DELAYED_REPREP:
846 scsi_mq_requeue_cmd(cmd, ALUA_TRANSITION_REPREP_DELAY);
849 /* Retry the same command immediately */
850 __scsi_queue_insert(cmd, SCSI_MLQUEUE_EH_RETRY, false);
852 case ACTION_DELAYED_RETRY:
853 /* Retry the same command after a delay */
854 __scsi_queue_insert(cmd, SCSI_MLQUEUE_DEVICE_BUSY, false);
860 * Helper for scsi_io_completion() when cmd->result is non-zero. Returns a
861 * new result that may suppress further error checking. Also modifies
862 * *blk_statp in some cases.
864 static int scsi_io_completion_nz_result(struct scsi_cmnd *cmd, int result,
865 blk_status_t *blk_statp)
868 bool sense_current = true; /* false implies "deferred sense" */
869 struct request *req = scsi_cmd_to_rq(cmd);
870 struct scsi_sense_hdr sshdr;
872 sense_valid = scsi_command_normalize_sense(cmd, &sshdr);
874 sense_current = !scsi_sense_is_deferred(&sshdr);
876 if (blk_rq_is_passthrough(req)) {
879 * SG_IO wants current and deferred errors
881 cmd->sense_len = min(8 + cmd->sense_buffer[7],
882 SCSI_SENSE_BUFFERSIZE);
885 *blk_statp = scsi_result_to_blk_status(result);
886 } else if (blk_rq_bytes(req) == 0 && sense_current) {
888 * Flush commands do not transfers any data, and thus cannot use
889 * good_bytes != blk_rq_bytes(req) as the signal for an error.
890 * This sets *blk_statp explicitly for the problem case.
892 *blk_statp = scsi_result_to_blk_status(result);
895 * Recovered errors need reporting, but they're always treated as
896 * success, so fiddle the result code here. For passthrough requests
897 * we already took a copy of the original into sreq->result which
898 * is what gets returned to the user
900 if (sense_valid && (sshdr.sense_key == RECOVERED_ERROR)) {
901 bool do_print = true;
903 * if ATA PASS-THROUGH INFORMATION AVAILABLE [0x0, 0x1d]
904 * skip print since caller wants ATA registers. Only occurs
905 * on SCSI ATA PASS_THROUGH commands when CK_COND=1
907 if ((sshdr.asc == 0x0) && (sshdr.ascq == 0x1d))
909 else if (req->rq_flags & RQF_QUIET)
912 scsi_print_sense(cmd);
914 /* for passthrough, *blk_statp may be set */
915 *blk_statp = BLK_STS_OK;
918 * Another corner case: the SCSI status byte is non-zero but 'good'.
919 * Example: PRE-FETCH command returns SAM_STAT_CONDITION_MET when
920 * it is able to fit nominated LBs in its cache (and SAM_STAT_GOOD
921 * if it can't fit). Treat SAM_STAT_CONDITION_MET and the related
922 * intermediate statuses (both obsolete in SAM-4) as good.
924 if ((result & 0xff) && scsi_status_is_good(result)) {
926 *blk_statp = BLK_STS_OK;
932 * scsi_io_completion - Completion processing for SCSI commands.
933 * @cmd: command that is finished.
934 * @good_bytes: number of processed bytes.
936 * We will finish off the specified number of sectors. If we are done, the
937 * command block will be released and the queue function will be goosed. If we
938 * are not done then we have to figure out what to do next:
940 * a) We can call scsi_mq_requeue_cmd(). The request will be
941 * unprepared and put back on the queue. Then a new command will
942 * be created for it. This should be used if we made forward
943 * progress, or if we want to switch from READ(10) to READ(6) for
946 * b) We can call scsi_io_completion_action(). The request will be
947 * put back on the queue and retried using the same command as
948 * before, possibly after a delay.
950 * c) We can call scsi_end_request() with blk_stat other than
951 * BLK_STS_OK, to fail the remainder of the request.
953 void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes)
955 int result = cmd->result;
956 struct request *req = scsi_cmd_to_rq(cmd);
957 blk_status_t blk_stat = BLK_STS_OK;
959 if (unlikely(result)) /* a nz result may or may not be an error */
960 result = scsi_io_completion_nz_result(cmd, result, &blk_stat);
963 * Next deal with any sectors which we were able to correctly
966 SCSI_LOG_HLCOMPLETE(1, scmd_printk(KERN_INFO, cmd,
967 "%u sectors total, %d bytes done.\n",
968 blk_rq_sectors(req), good_bytes));
971 * Failed, zero length commands always need to drop down
972 * to retry code. Fast path should return in this block.
974 if (likely(blk_rq_bytes(req) > 0 || blk_stat == BLK_STS_OK)) {
975 if (likely(!scsi_end_request(req, blk_stat, good_bytes)))
976 return; /* no bytes remaining */
979 /* Kill remainder if no retries. */
980 if (unlikely(blk_stat && scsi_noretry_cmd(cmd))) {
981 if (scsi_end_request(req, blk_stat, blk_rq_bytes(req)))
983 "Bytes remaining after failed, no-retry command");
988 * If there had been no error, but we have leftover bytes in the
989 * request just queue the command up again.
991 if (likely(result == 0))
992 scsi_mq_requeue_cmd(cmd, 0);
994 scsi_io_completion_action(cmd, result);
997 static inline bool scsi_cmd_needs_dma_drain(struct scsi_device *sdev,
1000 return sdev->dma_drain_len && blk_rq_is_passthrough(rq) &&
1001 !op_is_write(req_op(rq)) &&
1002 sdev->host->hostt->dma_need_drain(rq);
1006 * scsi_alloc_sgtables - Allocate and initialize data and integrity scatterlists
1007 * @cmd: SCSI command data structure to initialize.
1009 * Initializes @cmd->sdb and also @cmd->prot_sdb if data integrity is enabled
1013 * * BLK_STS_OK - on success
1014 * * BLK_STS_RESOURCE - if the failure is retryable
1015 * * BLK_STS_IOERR - if the failure is fatal
1017 blk_status_t scsi_alloc_sgtables(struct scsi_cmnd *cmd)
1019 struct scsi_device *sdev = cmd->device;
1020 struct request *rq = scsi_cmd_to_rq(cmd);
1021 unsigned short nr_segs = blk_rq_nr_phys_segments(rq);
1022 struct scatterlist *last_sg = NULL;
1024 bool need_drain = scsi_cmd_needs_dma_drain(sdev, rq);
1027 if (WARN_ON_ONCE(!nr_segs))
1028 return BLK_STS_IOERR;
1031 * Make sure there is space for the drain. The driver must adjust
1032 * max_hw_segments to be prepared for this.
1038 * If sg table allocation fails, requeue request later.
1040 if (unlikely(sg_alloc_table_chained(&cmd->sdb.table, nr_segs,
1041 cmd->sdb.table.sgl, SCSI_INLINE_SG_CNT)))
1042 return BLK_STS_RESOURCE;
1045 * Next, walk the list, and fill in the addresses and sizes of
1048 count = __blk_rq_map_sg(rq->q, rq, cmd->sdb.table.sgl, &last_sg);
1050 if (blk_rq_bytes(rq) & rq->q->dma_pad_mask) {
1051 unsigned int pad_len =
1052 (rq->q->dma_pad_mask & ~blk_rq_bytes(rq)) + 1;
1054 last_sg->length += pad_len;
1055 cmd->extra_len += pad_len;
1059 sg_unmark_end(last_sg);
1060 last_sg = sg_next(last_sg);
1061 sg_set_buf(last_sg, sdev->dma_drain_buf, sdev->dma_drain_len);
1062 sg_mark_end(last_sg);
1064 cmd->extra_len += sdev->dma_drain_len;
1068 BUG_ON(count > cmd->sdb.table.nents);
1069 cmd->sdb.table.nents = count;
1070 cmd->sdb.length = blk_rq_payload_bytes(rq);
1072 if (blk_integrity_rq(rq)) {
1073 struct scsi_data_buffer *prot_sdb = cmd->prot_sdb;
1076 if (WARN_ON_ONCE(!prot_sdb)) {
1078 * This can happen if someone (e.g. multipath)
1079 * queues a command to a device on an adapter
1080 * that does not support DIX.
1082 ret = BLK_STS_IOERR;
1083 goto out_free_sgtables;
1086 ivecs = blk_rq_count_integrity_sg(rq->q, rq->bio);
1088 if (sg_alloc_table_chained(&prot_sdb->table, ivecs,
1089 prot_sdb->table.sgl,
1090 SCSI_INLINE_PROT_SG_CNT)) {
1091 ret = BLK_STS_RESOURCE;
1092 goto out_free_sgtables;
1095 count = blk_rq_map_integrity_sg(rq->q, rq->bio,
1096 prot_sdb->table.sgl);
1097 BUG_ON(count > ivecs);
1098 BUG_ON(count > queue_max_integrity_segments(rq->q));
1100 cmd->prot_sdb = prot_sdb;
1101 cmd->prot_sdb->table.nents = count;
1106 scsi_free_sgtables(cmd);
1109 EXPORT_SYMBOL(scsi_alloc_sgtables);
1112 * scsi_initialize_rq - initialize struct scsi_cmnd partially
1113 * @rq: Request associated with the SCSI command to be initialized.
1115 * This function initializes the members of struct scsi_cmnd that must be
1116 * initialized before request processing starts and that won't be
1117 * reinitialized if a SCSI command is requeued.
1119 static void scsi_initialize_rq(struct request *rq)
1121 struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq);
1123 memset(cmd->cmnd, 0, sizeof(cmd->cmnd));
1124 cmd->cmd_len = MAX_COMMAND_SIZE;
1126 init_rcu_head(&cmd->rcu);
1127 cmd->jiffies_at_alloc = jiffies;
1131 struct request *scsi_alloc_request(struct request_queue *q, blk_opf_t opf,
1132 blk_mq_req_flags_t flags)
1136 rq = blk_mq_alloc_request(q, opf, flags);
1138 scsi_initialize_rq(rq);
1141 EXPORT_SYMBOL_GPL(scsi_alloc_request);
1144 * Only called when the request isn't completed by SCSI, and not freed by
1147 static void scsi_cleanup_rq(struct request *rq)
1149 if (rq->rq_flags & RQF_DONTPREP) {
1150 scsi_mq_uninit_cmd(blk_mq_rq_to_pdu(rq));
1151 rq->rq_flags &= ~RQF_DONTPREP;
1155 /* Called before a request is prepared. See also scsi_mq_prep_fn(). */
1156 void scsi_init_command(struct scsi_device *dev, struct scsi_cmnd *cmd)
1158 struct request *rq = scsi_cmd_to_rq(cmd);
1160 if (!blk_rq_is_passthrough(rq) && !(cmd->flags & SCMD_INITIALIZED)) {
1161 cmd->flags |= SCMD_INITIALIZED;
1162 scsi_initialize_rq(rq);
1166 INIT_LIST_HEAD(&cmd->eh_entry);
1167 INIT_DELAYED_WORK(&cmd->abort_work, scmd_eh_abort_handler);
1170 static blk_status_t scsi_setup_scsi_cmnd(struct scsi_device *sdev,
1171 struct request *req)
1173 struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req);
1176 * Passthrough requests may transfer data, in which case they must
1177 * a bio attached to them. Or they might contain a SCSI command
1178 * that does not transfer data, in which case they may optionally
1179 * submit a request without an attached bio.
1182 blk_status_t ret = scsi_alloc_sgtables(cmd);
1183 if (unlikely(ret != BLK_STS_OK))
1186 BUG_ON(blk_rq_bytes(req));
1188 memset(&cmd->sdb, 0, sizeof(cmd->sdb));
1191 cmd->transfersize = blk_rq_bytes(req);
1196 scsi_device_state_check(struct scsi_device *sdev, struct request *req)
1198 switch (sdev->sdev_state) {
1202 case SDEV_TRANSPORT_OFFLINE:
1204 * If the device is offline we refuse to process any
1205 * commands. The device must be brought online
1206 * before trying any recovery commands.
1208 if (!sdev->offline_already) {
1209 sdev->offline_already = true;
1210 sdev_printk(KERN_ERR, sdev,
1211 "rejecting I/O to offline device\n");
1213 return BLK_STS_IOERR;
1216 * If the device is fully deleted, we refuse to
1217 * process any commands as well.
1219 sdev_printk(KERN_ERR, sdev,
1220 "rejecting I/O to dead device\n");
1221 return BLK_STS_IOERR;
1223 case SDEV_CREATED_BLOCK:
1224 return BLK_STS_RESOURCE;
1227 * If the device is blocked we only accept power management
1230 if (req && WARN_ON_ONCE(!(req->rq_flags & RQF_PM)))
1231 return BLK_STS_RESOURCE;
1235 * For any other not fully online state we only allow
1236 * power management commands.
1238 if (req && !(req->rq_flags & RQF_PM))
1239 return BLK_STS_OFFLINE;
1245 * scsi_dev_queue_ready: if we can send requests to sdev, assign one token
1246 * and return the token else return -1.
1248 static inline int scsi_dev_queue_ready(struct request_queue *q,
1249 struct scsi_device *sdev)
1253 token = sbitmap_get(&sdev->budget_map);
1257 if (!atomic_read(&sdev->device_blocked))
1261 * Only unblock if no other commands are pending and
1262 * if device_blocked has decreased to zero
1264 if (scsi_device_busy(sdev) > 1 ||
1265 atomic_dec_return(&sdev->device_blocked) > 0) {
1266 sbitmap_put(&sdev->budget_map, token);
1270 SCSI_LOG_MLQUEUE(3, sdev_printk(KERN_INFO, sdev,
1271 "unblocking device at zero depth\n"));
1277 * scsi_target_queue_ready: checks if there we can send commands to target
1278 * @sdev: scsi device on starget to check.
1280 static inline int scsi_target_queue_ready(struct Scsi_Host *shost,
1281 struct scsi_device *sdev)
1283 struct scsi_target *starget = scsi_target(sdev);
1286 if (starget->single_lun) {
1287 spin_lock_irq(shost->host_lock);
1288 if (starget->starget_sdev_user &&
1289 starget->starget_sdev_user != sdev) {
1290 spin_unlock_irq(shost->host_lock);
1293 starget->starget_sdev_user = sdev;
1294 spin_unlock_irq(shost->host_lock);
1297 if (starget->can_queue <= 0)
1300 busy = atomic_inc_return(&starget->target_busy) - 1;
1301 if (atomic_read(&starget->target_blocked) > 0) {
1306 * unblock after target_blocked iterates to zero
1308 if (atomic_dec_return(&starget->target_blocked) > 0)
1311 SCSI_LOG_MLQUEUE(3, starget_printk(KERN_INFO, starget,
1312 "unblocking target at zero depth\n"));
1315 if (busy >= starget->can_queue)
1321 spin_lock_irq(shost->host_lock);
1322 list_move_tail(&sdev->starved_entry, &shost->starved_list);
1323 spin_unlock_irq(shost->host_lock);
1325 if (starget->can_queue > 0)
1326 atomic_dec(&starget->target_busy);
1331 * scsi_host_queue_ready: if we can send requests to shost, return 1 else
1332 * return 0. We must end up running the queue again whenever 0 is
1333 * returned, else IO can hang.
1335 static inline int scsi_host_queue_ready(struct request_queue *q,
1336 struct Scsi_Host *shost,
1337 struct scsi_device *sdev,
1338 struct scsi_cmnd *cmd)
1340 if (atomic_read(&shost->host_blocked) > 0) {
1341 if (scsi_host_busy(shost) > 0)
1345 * unblock after host_blocked iterates to zero
1347 if (atomic_dec_return(&shost->host_blocked) > 0)
1351 shost_printk(KERN_INFO, shost,
1352 "unblocking host at zero depth\n"));
1355 if (shost->host_self_blocked)
1358 /* We're OK to process the command, so we can't be starved */
1359 if (!list_empty(&sdev->starved_entry)) {
1360 spin_lock_irq(shost->host_lock);
1361 if (!list_empty(&sdev->starved_entry))
1362 list_del_init(&sdev->starved_entry);
1363 spin_unlock_irq(shost->host_lock);
1366 __set_bit(SCMD_STATE_INFLIGHT, &cmd->state);
1371 spin_lock_irq(shost->host_lock);
1372 if (list_empty(&sdev->starved_entry))
1373 list_add_tail(&sdev->starved_entry, &shost->starved_list);
1374 spin_unlock_irq(shost->host_lock);
1376 scsi_dec_host_busy(shost, cmd);
1381 * Busy state exporting function for request stacking drivers.
1383 * For efficiency, no lock is taken to check the busy state of
1384 * shost/starget/sdev, since the returned value is not guaranteed and
1385 * may be changed after request stacking drivers call the function,
1386 * regardless of taking lock or not.
1388 * When scsi can't dispatch I/Os anymore and needs to kill I/Os scsi
1389 * needs to return 'not busy'. Otherwise, request stacking drivers
1390 * may hold requests forever.
1392 static bool scsi_mq_lld_busy(struct request_queue *q)
1394 struct scsi_device *sdev = q->queuedata;
1395 struct Scsi_Host *shost;
1397 if (blk_queue_dying(q))
1403 * Ignore host/starget busy state.
1404 * Since block layer does not have a concept of fairness across
1405 * multiple queues, congestion of host/starget needs to be handled
1408 if (scsi_host_in_recovery(shost) || scsi_device_is_busy(sdev))
1415 * Block layer request completion callback. May be called from interrupt
1418 static void scsi_complete(struct request *rq)
1420 struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq);
1421 enum scsi_disposition disposition;
1423 INIT_LIST_HEAD(&cmd->eh_entry);
1425 atomic_inc(&cmd->device->iodone_cnt);
1427 atomic_inc(&cmd->device->ioerr_cnt);
1429 disposition = scsi_decide_disposition(cmd);
1430 if (disposition != SUCCESS && scsi_cmd_runtime_exceeced(cmd))
1431 disposition = SUCCESS;
1433 scsi_log_completion(cmd, disposition);
1435 switch (disposition) {
1437 scsi_finish_command(cmd);
1440 scsi_queue_insert(cmd, SCSI_MLQUEUE_EH_RETRY);
1442 case ADD_TO_MLQUEUE:
1443 scsi_queue_insert(cmd, SCSI_MLQUEUE_DEVICE_BUSY);
1446 scsi_eh_scmd_add(cmd);
1452 * scsi_dispatch_cmd - Dispatch a command to the low-level driver.
1453 * @cmd: command block we are dispatching.
1455 * Return: nonzero return request was rejected and device's queue needs to be
1458 static int scsi_dispatch_cmd(struct scsi_cmnd *cmd)
1460 struct Scsi_Host *host = cmd->device->host;
1463 atomic_inc(&cmd->device->iorequest_cnt);
1465 /* check if the device is still usable */
1466 if (unlikely(cmd->device->sdev_state == SDEV_DEL)) {
1467 /* in SDEV_DEL we error all commands. DID_NO_CONNECT
1468 * returns an immediate error upwards, and signals
1469 * that the device is no longer present */
1470 cmd->result = DID_NO_CONNECT << 16;
1474 /* Check to see if the scsi lld made this device blocked. */
1475 if (unlikely(scsi_device_blocked(cmd->device))) {
1477 * in blocked state, the command is just put back on
1478 * the device queue. The suspend state has already
1479 * blocked the queue so future requests should not
1480 * occur until the device transitions out of the
1483 SCSI_LOG_MLQUEUE(3, scmd_printk(KERN_INFO, cmd,
1484 "queuecommand : device blocked\n"));
1485 atomic_dec(&cmd->device->iorequest_cnt);
1486 return SCSI_MLQUEUE_DEVICE_BUSY;
1489 /* Store the LUN value in cmnd, if needed. */
1490 if (cmd->device->lun_in_cdb)
1491 cmd->cmnd[1] = (cmd->cmnd[1] & 0x1f) |
1492 (cmd->device->lun << 5 & 0xe0);
1497 * Before we queue this command, check if the command
1498 * length exceeds what the host adapter can handle.
1500 if (cmd->cmd_len > cmd->device->host->max_cmd_len) {
1501 SCSI_LOG_MLQUEUE(3, scmd_printk(KERN_INFO, cmd,
1502 "queuecommand : command too long. "
1503 "cdb_size=%d host->max_cmd_len=%d\n",
1504 cmd->cmd_len, cmd->device->host->max_cmd_len));
1505 cmd->result = (DID_ABORT << 16);
1509 if (unlikely(host->shost_state == SHOST_DEL)) {
1510 cmd->result = (DID_NO_CONNECT << 16);
1515 trace_scsi_dispatch_cmd_start(cmd);
1516 rtn = host->hostt->queuecommand(host, cmd);
1518 atomic_dec(&cmd->device->iorequest_cnt);
1519 trace_scsi_dispatch_cmd_error(cmd, rtn);
1520 if (rtn != SCSI_MLQUEUE_DEVICE_BUSY &&
1521 rtn != SCSI_MLQUEUE_TARGET_BUSY)
1522 rtn = SCSI_MLQUEUE_HOST_BUSY;
1524 SCSI_LOG_MLQUEUE(3, scmd_printk(KERN_INFO, cmd,
1525 "queuecommand : request rejected\n"));
1534 /* Size in bytes of the sg-list stored in the scsi-mq command-private data. */
1535 static unsigned int scsi_mq_inline_sgl_size(struct Scsi_Host *shost)
1537 return min_t(unsigned int, shost->sg_tablesize, SCSI_INLINE_SG_CNT) *
1538 sizeof(struct scatterlist);
1541 static blk_status_t scsi_prepare_cmd(struct request *req)
1543 struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req);
1544 struct scsi_device *sdev = req->q->queuedata;
1545 struct Scsi_Host *shost = sdev->host;
1546 bool in_flight = test_bit(SCMD_STATE_INFLIGHT, &cmd->state);
1547 struct scatterlist *sg;
1549 scsi_init_command(sdev, cmd);
1553 cmd->prot_flags = 0;
1555 memset(&cmd->sdb, 0, sizeof(cmd->sdb));
1557 cmd->transfersize = 0;
1558 cmd->host_scribble = NULL;
1563 __set_bit(SCMD_STATE_INFLIGHT, &cmd->state);
1566 * Only clear the driver-private command data if the LLD does not supply
1567 * a function to initialize that data.
1569 if (!shost->hostt->init_cmd_priv)
1570 memset(cmd + 1, 0, shost->hostt->cmd_size);
1572 cmd->prot_op = SCSI_PROT_NORMAL;
1573 if (blk_rq_bytes(req))
1574 cmd->sc_data_direction = rq_dma_dir(req);
1576 cmd->sc_data_direction = DMA_NONE;
1578 sg = (void *)cmd + sizeof(struct scsi_cmnd) + shost->hostt->cmd_size;
1579 cmd->sdb.table.sgl = sg;
1581 if (scsi_host_get_prot(shost)) {
1582 memset(cmd->prot_sdb, 0, sizeof(struct scsi_data_buffer));
1584 cmd->prot_sdb->table.sgl =
1585 (struct scatterlist *)(cmd->prot_sdb + 1);
1589 * Special handling for passthrough commands, which don't go to the ULP
1592 if (blk_rq_is_passthrough(req))
1593 return scsi_setup_scsi_cmnd(sdev, req);
1595 if (sdev->handler && sdev->handler->prep_fn) {
1596 blk_status_t ret = sdev->handler->prep_fn(sdev, req);
1598 if (ret != BLK_STS_OK)
1602 /* Usually overridden by the ULP */
1604 memset(cmd->cmnd, 0, sizeof(cmd->cmnd));
1605 return scsi_cmd_to_driver(cmd)->init_command(cmd);
1608 static void scsi_done_internal(struct scsi_cmnd *cmd, bool complete_directly)
1610 struct request *req = scsi_cmd_to_rq(cmd);
1612 switch (cmd->submitter) {
1613 case SUBMITTED_BY_BLOCK_LAYER:
1615 case SUBMITTED_BY_SCSI_ERROR_HANDLER:
1616 return scsi_eh_done(cmd);
1617 case SUBMITTED_BY_SCSI_RESET_IOCTL:
1621 if (unlikely(blk_should_fake_timeout(scsi_cmd_to_rq(cmd)->q)))
1623 if (unlikely(test_and_set_bit(SCMD_STATE_COMPLETE, &cmd->state)))
1625 trace_scsi_dispatch_cmd_done(cmd);
1627 if (complete_directly)
1628 blk_mq_complete_request_direct(req, scsi_complete);
1630 blk_mq_complete_request(req);
1633 void scsi_done(struct scsi_cmnd *cmd)
1635 scsi_done_internal(cmd, false);
1637 EXPORT_SYMBOL(scsi_done);
1639 void scsi_done_direct(struct scsi_cmnd *cmd)
1641 scsi_done_internal(cmd, true);
1643 EXPORT_SYMBOL(scsi_done_direct);
1645 static void scsi_mq_put_budget(struct request_queue *q, int budget_token)
1647 struct scsi_device *sdev = q->queuedata;
1649 sbitmap_put(&sdev->budget_map, budget_token);
1653 * When to reinvoke queueing after a resource shortage. It's 3 msecs to
1654 * not change behaviour from the previous unplug mechanism, experimentation
1655 * may prove this needs changing.
1657 #define SCSI_QUEUE_DELAY 3
1659 static int scsi_mq_get_budget(struct request_queue *q)
1661 struct scsi_device *sdev = q->queuedata;
1662 int token = scsi_dev_queue_ready(q, sdev);
1667 atomic_inc(&sdev->restarts);
1670 * Orders atomic_inc(&sdev->restarts) and atomic_read(&sdev->device_busy).
1671 * .restarts must be incremented before .device_busy is read because the
1672 * code in scsi_run_queue_async() depends on the order of these operations.
1674 smp_mb__after_atomic();
1677 * If all in-flight requests originated from this LUN are completed
1678 * before reading .device_busy, sdev->device_busy will be observed as
1679 * zero, then blk_mq_delay_run_hw_queues() will dispatch this request
1680 * soon. Otherwise, completion of one of these requests will observe
1681 * the .restarts flag, and the request queue will be run for handling
1682 * this request, see scsi_end_request().
1684 if (unlikely(scsi_device_busy(sdev) == 0 &&
1685 !scsi_device_blocked(sdev)))
1686 blk_mq_delay_run_hw_queues(sdev->request_queue, SCSI_QUEUE_DELAY);
1690 static void scsi_mq_set_rq_budget_token(struct request *req, int token)
1692 struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req);
1694 cmd->budget_token = token;
1697 static int scsi_mq_get_rq_budget_token(struct request *req)
1699 struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req);
1701 return cmd->budget_token;
1704 static blk_status_t scsi_queue_rq(struct blk_mq_hw_ctx *hctx,
1705 const struct blk_mq_queue_data *bd)
1707 struct request *req = bd->rq;
1708 struct request_queue *q = req->q;
1709 struct scsi_device *sdev = q->queuedata;
1710 struct Scsi_Host *shost = sdev->host;
1711 struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req);
1715 WARN_ON_ONCE(cmd->budget_token < 0);
1718 * If the device is not in running state we will reject some or all
1721 if (unlikely(sdev->sdev_state != SDEV_RUNNING)) {
1722 ret = scsi_device_state_check(sdev, req);
1723 if (ret != BLK_STS_OK)
1724 goto out_put_budget;
1727 ret = BLK_STS_RESOURCE;
1728 if (!scsi_target_queue_ready(shost, sdev))
1729 goto out_put_budget;
1730 if (unlikely(scsi_host_in_recovery(shost))) {
1731 if (cmd->flags & SCMD_FAIL_IF_RECOVERING)
1732 ret = BLK_STS_OFFLINE;
1733 goto out_dec_target_busy;
1735 if (!scsi_host_queue_ready(q, shost, sdev, cmd))
1736 goto out_dec_target_busy;
1738 if (!(req->rq_flags & RQF_DONTPREP)) {
1739 ret = scsi_prepare_cmd(req);
1740 if (ret != BLK_STS_OK)
1741 goto out_dec_host_busy;
1742 req->rq_flags |= RQF_DONTPREP;
1744 clear_bit(SCMD_STATE_COMPLETE, &cmd->state);
1747 cmd->flags &= SCMD_PRESERVED_FLAGS;
1748 if (sdev->simple_tags)
1749 cmd->flags |= SCMD_TAGGED;
1751 cmd->flags |= SCMD_LAST;
1753 scsi_set_resid(cmd, 0);
1754 memset(cmd->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE);
1755 cmd->submitter = SUBMITTED_BY_BLOCK_LAYER;
1757 blk_mq_start_request(req);
1758 reason = scsi_dispatch_cmd(cmd);
1760 scsi_set_blocked(cmd, reason);
1761 ret = BLK_STS_RESOURCE;
1762 goto out_dec_host_busy;
1768 scsi_dec_host_busy(shost, cmd);
1769 out_dec_target_busy:
1770 if (scsi_target(sdev)->can_queue > 0)
1771 atomic_dec(&scsi_target(sdev)->target_busy);
1773 scsi_mq_put_budget(q, cmd->budget_token);
1774 cmd->budget_token = -1;
1778 case BLK_STS_RESOURCE:
1779 case BLK_STS_ZONE_RESOURCE:
1780 if (scsi_device_blocked(sdev))
1781 ret = BLK_STS_DEV_RESOURCE;
1784 cmd->result = DID_BUS_BUSY << 16;
1785 if (req->rq_flags & RQF_DONTPREP)
1786 scsi_mq_uninit_cmd(cmd);
1789 if (unlikely(!scsi_device_online(sdev)))
1790 cmd->result = DID_NO_CONNECT << 16;
1792 cmd->result = DID_ERROR << 16;
1794 * Make sure to release all allocated resources when
1795 * we hit an error, as we will never see this command
1798 if (req->rq_flags & RQF_DONTPREP)
1799 scsi_mq_uninit_cmd(cmd);
1800 scsi_run_queue_async(sdev);
1806 static int scsi_mq_init_request(struct blk_mq_tag_set *set, struct request *rq,
1807 unsigned int hctx_idx, unsigned int numa_node)
1809 struct Scsi_Host *shost = set->driver_data;
1810 struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq);
1811 struct scatterlist *sg;
1815 kmem_cache_alloc_node(scsi_sense_cache, GFP_KERNEL, numa_node);
1816 if (!cmd->sense_buffer)
1819 if (scsi_host_get_prot(shost)) {
1820 sg = (void *)cmd + sizeof(struct scsi_cmnd) +
1821 shost->hostt->cmd_size;
1822 cmd->prot_sdb = (void *)sg + scsi_mq_inline_sgl_size(shost);
1825 if (shost->hostt->init_cmd_priv) {
1826 ret = shost->hostt->init_cmd_priv(shost, cmd);
1828 kmem_cache_free(scsi_sense_cache, cmd->sense_buffer);
1834 static void scsi_mq_exit_request(struct blk_mq_tag_set *set, struct request *rq,
1835 unsigned int hctx_idx)
1837 struct Scsi_Host *shost = set->driver_data;
1838 struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq);
1840 if (shost->hostt->exit_cmd_priv)
1841 shost->hostt->exit_cmd_priv(shost, cmd);
1842 kmem_cache_free(scsi_sense_cache, cmd->sense_buffer);
1846 static int scsi_mq_poll(struct blk_mq_hw_ctx *hctx, struct io_comp_batch *iob)
1848 struct Scsi_Host *shost = hctx->driver_data;
1850 if (shost->hostt->mq_poll)
1851 return shost->hostt->mq_poll(shost, hctx->queue_num);
1856 static int scsi_init_hctx(struct blk_mq_hw_ctx *hctx, void *data,
1857 unsigned int hctx_idx)
1859 struct Scsi_Host *shost = data;
1861 hctx->driver_data = shost;
1865 static void scsi_map_queues(struct blk_mq_tag_set *set)
1867 struct Scsi_Host *shost = container_of(set, struct Scsi_Host, tag_set);
1869 if (shost->hostt->map_queues)
1870 return shost->hostt->map_queues(shost);
1871 blk_mq_map_queues(&set->map[HCTX_TYPE_DEFAULT]);
1874 void __scsi_init_queue(struct Scsi_Host *shost, struct request_queue *q)
1876 struct device *dev = shost->dma_dev;
1879 * this limit is imposed by hardware restrictions
1881 blk_queue_max_segments(q, min_t(unsigned short, shost->sg_tablesize,
1884 if (scsi_host_prot_dma(shost)) {
1885 shost->sg_prot_tablesize =
1886 min_not_zero(shost->sg_prot_tablesize,
1887 (unsigned short)SCSI_MAX_PROT_SG_SEGMENTS);
1888 BUG_ON(shost->sg_prot_tablesize < shost->sg_tablesize);
1889 blk_queue_max_integrity_segments(q, shost->sg_prot_tablesize);
1892 blk_queue_max_hw_sectors(q, shost->max_sectors);
1893 blk_queue_segment_boundary(q, shost->dma_boundary);
1894 dma_set_seg_boundary(dev, shost->dma_boundary);
1896 blk_queue_max_segment_size(q, shost->max_segment_size);
1897 blk_queue_virt_boundary(q, shost->virt_boundary_mask);
1898 dma_set_max_seg_size(dev, queue_max_segment_size(q));
1901 * Set a reasonable default alignment: The larger of 32-byte (dword),
1902 * which is a common minimum for HBAs, and the minimum DMA alignment,
1903 * which is set by the platform.
1905 * Devices that require a bigger alignment can increase it later.
1907 blk_queue_dma_alignment(q, max(4, dma_get_cache_alignment()) - 1);
1909 EXPORT_SYMBOL_GPL(__scsi_init_queue);
1911 static const struct blk_mq_ops scsi_mq_ops_no_commit = {
1912 .get_budget = scsi_mq_get_budget,
1913 .put_budget = scsi_mq_put_budget,
1914 .queue_rq = scsi_queue_rq,
1915 .complete = scsi_complete,
1916 .timeout = scsi_timeout,
1917 #ifdef CONFIG_BLK_DEBUG_FS
1918 .show_rq = scsi_show_rq,
1920 .init_request = scsi_mq_init_request,
1921 .exit_request = scsi_mq_exit_request,
1922 .cleanup_rq = scsi_cleanup_rq,
1923 .busy = scsi_mq_lld_busy,
1924 .map_queues = scsi_map_queues,
1925 .init_hctx = scsi_init_hctx,
1926 .poll = scsi_mq_poll,
1927 .set_rq_budget_token = scsi_mq_set_rq_budget_token,
1928 .get_rq_budget_token = scsi_mq_get_rq_budget_token,
1932 static void scsi_commit_rqs(struct blk_mq_hw_ctx *hctx)
1934 struct Scsi_Host *shost = hctx->driver_data;
1936 shost->hostt->commit_rqs(shost, hctx->queue_num);
1939 static const struct blk_mq_ops scsi_mq_ops = {
1940 .get_budget = scsi_mq_get_budget,
1941 .put_budget = scsi_mq_put_budget,
1942 .queue_rq = scsi_queue_rq,
1943 .commit_rqs = scsi_commit_rqs,
1944 .complete = scsi_complete,
1945 .timeout = scsi_timeout,
1946 #ifdef CONFIG_BLK_DEBUG_FS
1947 .show_rq = scsi_show_rq,
1949 .init_request = scsi_mq_init_request,
1950 .exit_request = scsi_mq_exit_request,
1951 .cleanup_rq = scsi_cleanup_rq,
1952 .busy = scsi_mq_lld_busy,
1953 .map_queues = scsi_map_queues,
1954 .init_hctx = scsi_init_hctx,
1955 .poll = scsi_mq_poll,
1956 .set_rq_budget_token = scsi_mq_set_rq_budget_token,
1957 .get_rq_budget_token = scsi_mq_get_rq_budget_token,
1960 int scsi_mq_setup_tags(struct Scsi_Host *shost)
1962 unsigned int cmd_size, sgl_size;
1963 struct blk_mq_tag_set *tag_set = &shost->tag_set;
1965 sgl_size = max_t(unsigned int, sizeof(struct scatterlist),
1966 scsi_mq_inline_sgl_size(shost));
1967 cmd_size = sizeof(struct scsi_cmnd) + shost->hostt->cmd_size + sgl_size;
1968 if (scsi_host_get_prot(shost))
1969 cmd_size += sizeof(struct scsi_data_buffer) +
1970 sizeof(struct scatterlist) * SCSI_INLINE_PROT_SG_CNT;
1972 memset(tag_set, 0, sizeof(*tag_set));
1973 if (shost->hostt->commit_rqs)
1974 tag_set->ops = &scsi_mq_ops;
1976 tag_set->ops = &scsi_mq_ops_no_commit;
1977 tag_set->nr_hw_queues = shost->nr_hw_queues ? : 1;
1978 tag_set->nr_maps = shost->nr_maps ? : 1;
1979 tag_set->queue_depth = shost->can_queue;
1980 tag_set->cmd_size = cmd_size;
1981 tag_set->numa_node = dev_to_node(shost->dma_dev);
1982 tag_set->flags = BLK_MQ_F_SHOULD_MERGE;
1984 BLK_ALLOC_POLICY_TO_MQ_FLAG(shost->hostt->tag_alloc_policy);
1985 if (shost->queuecommand_may_block)
1986 tag_set->flags |= BLK_MQ_F_BLOCKING;
1987 tag_set->driver_data = shost;
1988 if (shost->host_tagset)
1989 tag_set->flags |= BLK_MQ_F_TAG_HCTX_SHARED;
1991 return blk_mq_alloc_tag_set(tag_set);
1994 void scsi_mq_free_tags(struct kref *kref)
1996 struct Scsi_Host *shost = container_of(kref, typeof(*shost),
1999 blk_mq_free_tag_set(&shost->tag_set);
2000 complete(&shost->tagset_freed);
2004 * scsi_device_from_queue - return sdev associated with a request_queue
2005 * @q: The request queue to return the sdev from
2007 * Return the sdev associated with a request queue or NULL if the
2008 * request_queue does not reference a SCSI device.
2010 struct scsi_device *scsi_device_from_queue(struct request_queue *q)
2012 struct scsi_device *sdev = NULL;
2014 if (q->mq_ops == &scsi_mq_ops_no_commit ||
2015 q->mq_ops == &scsi_mq_ops)
2016 sdev = q->queuedata;
2017 if (!sdev || !get_device(&sdev->sdev_gendev))
2023 * pktcdvd should have been integrated into the SCSI layers, but for historical
2024 * reasons like the old IDE driver it isn't. This export allows it to safely
2025 * probe if a given device is a SCSI one and only attach to that.
2027 #ifdef CONFIG_CDROM_PKTCDVD_MODULE
2028 EXPORT_SYMBOL_GPL(scsi_device_from_queue);
2032 * scsi_block_requests - Utility function used by low-level drivers to prevent
2033 * further commands from being queued to the device.
2034 * @shost: host in question
2036 * There is no timer nor any other means by which the requests get unblocked
2037 * other than the low-level driver calling scsi_unblock_requests().
2039 void scsi_block_requests(struct Scsi_Host *shost)
2041 shost->host_self_blocked = 1;
2043 EXPORT_SYMBOL(scsi_block_requests);
2046 * scsi_unblock_requests - Utility function used by low-level drivers to allow
2047 * further commands to be queued to the device.
2048 * @shost: host in question
2050 * There is no timer nor any other means by which the requests get unblocked
2051 * other than the low-level driver calling scsi_unblock_requests(). This is done
2052 * as an API function so that changes to the internals of the scsi mid-layer
2053 * won't require wholesale changes to drivers that use this feature.
2055 void scsi_unblock_requests(struct Scsi_Host *shost)
2057 shost->host_self_blocked = 0;
2058 scsi_run_host_queues(shost);
2060 EXPORT_SYMBOL(scsi_unblock_requests);
2062 void scsi_exit_queue(void)
2064 kmem_cache_destroy(scsi_sense_cache);
2068 * scsi_mode_select - issue a mode select
2069 * @sdev: SCSI device to be queried
2070 * @pf: Page format bit (1 == standard, 0 == vendor specific)
2071 * @sp: Save page bit (0 == don't save, 1 == save)
2072 * @buffer: request buffer (may not be smaller than eight bytes)
2073 * @len: length of request buffer.
2074 * @timeout: command timeout
2075 * @retries: number of retries before failing
2076 * @data: returns a structure abstracting the mode header data
2077 * @sshdr: place to put sense data (or NULL if no sense to be collected).
2078 * must be SCSI_SENSE_BUFFERSIZE big.
2080 * Returns zero if successful; negative error number or scsi
2084 int scsi_mode_select(struct scsi_device *sdev, int pf, int sp,
2085 unsigned char *buffer, int len, int timeout, int retries,
2086 struct scsi_mode_data *data, struct scsi_sense_hdr *sshdr)
2088 unsigned char cmd[10];
2089 unsigned char *real_buffer;
2090 const struct scsi_exec_args exec_args = {
2095 memset(cmd, 0, sizeof(cmd));
2096 cmd[1] = (pf ? 0x10 : 0) | (sp ? 0x01 : 0);
2099 * Use MODE SELECT(10) if the device asked for it or if the mode page
2100 * and the mode select header cannot fit within the maximumm 255 bytes
2101 * of the MODE SELECT(6) command.
2103 if (sdev->use_10_for_ms ||
2105 data->block_descriptor_length > 255) {
2106 if (len > 65535 - 8)
2108 real_buffer = kmalloc(8 + len, GFP_KERNEL);
2111 memcpy(real_buffer + 8, buffer, len);
2115 real_buffer[2] = data->medium_type;
2116 real_buffer[3] = data->device_specific;
2117 real_buffer[4] = data->longlba ? 0x01 : 0;
2119 put_unaligned_be16(data->block_descriptor_length,
2122 cmd[0] = MODE_SELECT_10;
2123 put_unaligned_be16(len, &cmd[7]);
2128 real_buffer = kmalloc(4 + len, GFP_KERNEL);
2131 memcpy(real_buffer + 4, buffer, len);
2134 real_buffer[1] = data->medium_type;
2135 real_buffer[2] = data->device_specific;
2136 real_buffer[3] = data->block_descriptor_length;
2138 cmd[0] = MODE_SELECT;
2142 ret = scsi_execute_cmd(sdev, cmd, REQ_OP_DRV_OUT, real_buffer, len,
2143 timeout, retries, &exec_args);
2147 EXPORT_SYMBOL_GPL(scsi_mode_select);
2150 * scsi_mode_sense - issue a mode sense, falling back from 10 to six bytes if necessary.
2151 * @sdev: SCSI device to be queried
2152 * @dbd: set to prevent mode sense from returning block descriptors
2153 * @modepage: mode page being requested
2154 * @subpage: sub-page of the mode page being requested
2155 * @buffer: request buffer (may not be smaller than eight bytes)
2156 * @len: length of request buffer.
2157 * @timeout: command timeout
2158 * @retries: number of retries before failing
2159 * @data: returns a structure abstracting the mode header data
2160 * @sshdr: place to put sense data (or NULL if no sense to be collected).
2161 * must be SCSI_SENSE_BUFFERSIZE big.
2163 * Returns zero if successful, or a negative error number on failure
2166 scsi_mode_sense(struct scsi_device *sdev, int dbd, int modepage, int subpage,
2167 unsigned char *buffer, int len, int timeout, int retries,
2168 struct scsi_mode_data *data, struct scsi_sense_hdr *sshdr)
2170 unsigned char cmd[12];
2173 int result, retry_count = retries;
2174 struct scsi_sense_hdr my_sshdr;
2175 const struct scsi_exec_args exec_args = {
2176 /* caller might not be interested in sense, but we need it */
2177 .sshdr = sshdr ? : &my_sshdr,
2180 memset(data, 0, sizeof(*data));
2181 memset(&cmd[0], 0, 12);
2183 dbd = sdev->set_dbd_for_ms ? 8 : dbd;
2184 cmd[1] = dbd & 0x18; /* allows DBD and LLBA bits */
2188 sshdr = exec_args.sshdr;
2191 use_10_for_ms = sdev->use_10_for_ms || len > 255;
2193 if (use_10_for_ms) {
2194 if (len < 8 || len > 65535)
2197 cmd[0] = MODE_SENSE_10;
2198 put_unaligned_be16(len, &cmd[7]);
2204 cmd[0] = MODE_SENSE;
2209 memset(buffer, 0, len);
2211 result = scsi_execute_cmd(sdev, cmd, REQ_OP_DRV_IN, buffer, len,
2212 timeout, retries, &exec_args);
2216 /* This code looks awful: what it's doing is making sure an
2217 * ILLEGAL REQUEST sense return identifies the actual command
2218 * byte as the problem. MODE_SENSE commands can return
2219 * ILLEGAL REQUEST if the code page isn't supported */
2221 if (!scsi_status_is_good(result)) {
2222 if (scsi_sense_valid(sshdr)) {
2223 if ((sshdr->sense_key == ILLEGAL_REQUEST) &&
2224 (sshdr->asc == 0x20) && (sshdr->ascq == 0)) {
2226 * Invalid command operation code: retry using
2227 * MODE SENSE(6) if this was a MODE SENSE(10)
2228 * request, except if the request mode page is
2229 * too large for MODE SENSE single byte
2230 * allocation length field.
2232 if (use_10_for_ms) {
2235 sdev->use_10_for_ms = 0;
2239 if (scsi_status_is_check_condition(result) &&
2240 sshdr->sense_key == UNIT_ATTENTION &&
2248 if (unlikely(buffer[0] == 0x86 && buffer[1] == 0x0b &&
2249 (modepage == 6 || modepage == 8))) {
2250 /* Initio breakage? */
2253 data->medium_type = 0;
2254 data->device_specific = 0;
2256 data->block_descriptor_length = 0;
2257 } else if (use_10_for_ms) {
2258 data->length = get_unaligned_be16(&buffer[0]) + 2;
2259 data->medium_type = buffer[2];
2260 data->device_specific = buffer[3];
2261 data->longlba = buffer[4] & 0x01;
2262 data->block_descriptor_length = get_unaligned_be16(&buffer[6]);
2264 data->length = buffer[0] + 1;
2265 data->medium_type = buffer[1];
2266 data->device_specific = buffer[2];
2267 data->block_descriptor_length = buffer[3];
2269 data->header_length = header_length;
2273 EXPORT_SYMBOL(scsi_mode_sense);
2276 * scsi_test_unit_ready - test if unit is ready
2277 * @sdev: scsi device to change the state of.
2278 * @timeout: command timeout
2279 * @retries: number of retries before failing
2280 * @sshdr: outpout pointer for decoded sense information.
2282 * Returns zero if unsuccessful or an error if TUR failed. For
2283 * removable media, UNIT_ATTENTION sets ->changed flag.
2286 scsi_test_unit_ready(struct scsi_device *sdev, int timeout, int retries,
2287 struct scsi_sense_hdr *sshdr)
2290 TEST_UNIT_READY, 0, 0, 0, 0, 0,
2292 const struct scsi_exec_args exec_args = {
2297 /* try to eat the UNIT_ATTENTION if there are enough retries */
2299 result = scsi_execute_cmd(sdev, cmd, REQ_OP_DRV_IN, NULL, 0,
2300 timeout, 1, &exec_args);
2301 if (sdev->removable && result > 0 && scsi_sense_valid(sshdr) &&
2302 sshdr->sense_key == UNIT_ATTENTION)
2304 } while (result > 0 && scsi_sense_valid(sshdr) &&
2305 sshdr->sense_key == UNIT_ATTENTION && --retries);
2309 EXPORT_SYMBOL(scsi_test_unit_ready);
2312 * scsi_device_set_state - Take the given device through the device state model.
2313 * @sdev: scsi device to change the state of.
2314 * @state: state to change to.
2316 * Returns zero if successful or an error if the requested
2317 * transition is illegal.
2320 scsi_device_set_state(struct scsi_device *sdev, enum scsi_device_state state)
2322 enum scsi_device_state oldstate = sdev->sdev_state;
2324 if (state == oldstate)
2330 case SDEV_CREATED_BLOCK:
2341 case SDEV_TRANSPORT_OFFLINE:
2354 case SDEV_TRANSPORT_OFFLINE:
2362 case SDEV_TRANSPORT_OFFLINE:
2377 case SDEV_CREATED_BLOCK:
2386 case SDEV_CREATED_BLOCK:
2401 case SDEV_TRANSPORT_OFFLINE:
2413 case SDEV_TRANSPORT_OFFLINE:
2416 case SDEV_CREATED_BLOCK:
2424 sdev->offline_already = false;
2425 sdev->sdev_state = state;
2429 SCSI_LOG_ERROR_RECOVERY(1,
2430 sdev_printk(KERN_ERR, sdev,
2431 "Illegal state transition %s->%s",
2432 scsi_device_state_name(oldstate),
2433 scsi_device_state_name(state))
2437 EXPORT_SYMBOL(scsi_device_set_state);
2440 * scsi_evt_emit - emit a single SCSI device uevent
2441 * @sdev: associated SCSI device
2442 * @evt: event to emit
2444 * Send a single uevent (scsi_event) to the associated scsi_device.
2446 static void scsi_evt_emit(struct scsi_device *sdev, struct scsi_event *evt)
2451 switch (evt->evt_type) {
2452 case SDEV_EVT_MEDIA_CHANGE:
2453 envp[idx++] = "SDEV_MEDIA_CHANGE=1";
2455 case SDEV_EVT_INQUIRY_CHANGE_REPORTED:
2456 scsi_rescan_device(sdev);
2457 envp[idx++] = "SDEV_UA=INQUIRY_DATA_HAS_CHANGED";
2459 case SDEV_EVT_CAPACITY_CHANGE_REPORTED:
2460 envp[idx++] = "SDEV_UA=CAPACITY_DATA_HAS_CHANGED";
2462 case SDEV_EVT_SOFT_THRESHOLD_REACHED_REPORTED:
2463 envp[idx++] = "SDEV_UA=THIN_PROVISIONING_SOFT_THRESHOLD_REACHED";
2465 case SDEV_EVT_MODE_PARAMETER_CHANGE_REPORTED:
2466 envp[idx++] = "SDEV_UA=MODE_PARAMETERS_CHANGED";
2468 case SDEV_EVT_LUN_CHANGE_REPORTED:
2469 envp[idx++] = "SDEV_UA=REPORTED_LUNS_DATA_HAS_CHANGED";
2471 case SDEV_EVT_ALUA_STATE_CHANGE_REPORTED:
2472 envp[idx++] = "SDEV_UA=ASYMMETRIC_ACCESS_STATE_CHANGED";
2474 case SDEV_EVT_POWER_ON_RESET_OCCURRED:
2475 envp[idx++] = "SDEV_UA=POWER_ON_RESET_OCCURRED";
2484 kobject_uevent_env(&sdev->sdev_gendev.kobj, KOBJ_CHANGE, envp);
2488 * scsi_evt_thread - send a uevent for each scsi event
2489 * @work: work struct for scsi_device
2491 * Dispatch queued events to their associated scsi_device kobjects
2494 void scsi_evt_thread(struct work_struct *work)
2496 struct scsi_device *sdev;
2497 enum scsi_device_event evt_type;
2498 LIST_HEAD(event_list);
2500 sdev = container_of(work, struct scsi_device, event_work);
2502 for (evt_type = SDEV_EVT_FIRST; evt_type <= SDEV_EVT_LAST; evt_type++)
2503 if (test_and_clear_bit(evt_type, sdev->pending_events))
2504 sdev_evt_send_simple(sdev, evt_type, GFP_KERNEL);
2507 struct scsi_event *evt;
2508 struct list_head *this, *tmp;
2509 unsigned long flags;
2511 spin_lock_irqsave(&sdev->list_lock, flags);
2512 list_splice_init(&sdev->event_list, &event_list);
2513 spin_unlock_irqrestore(&sdev->list_lock, flags);
2515 if (list_empty(&event_list))
2518 list_for_each_safe(this, tmp, &event_list) {
2519 evt = list_entry(this, struct scsi_event, node);
2520 list_del(&evt->node);
2521 scsi_evt_emit(sdev, evt);
2528 * sdev_evt_send - send asserted event to uevent thread
2529 * @sdev: scsi_device event occurred on
2530 * @evt: event to send
2532 * Assert scsi device event asynchronously.
2534 void sdev_evt_send(struct scsi_device *sdev, struct scsi_event *evt)
2536 unsigned long flags;
2539 /* FIXME: currently this check eliminates all media change events
2540 * for polled devices. Need to update to discriminate between AN
2541 * and polled events */
2542 if (!test_bit(evt->evt_type, sdev->supported_events)) {
2548 spin_lock_irqsave(&sdev->list_lock, flags);
2549 list_add_tail(&evt->node, &sdev->event_list);
2550 schedule_work(&sdev->event_work);
2551 spin_unlock_irqrestore(&sdev->list_lock, flags);
2553 EXPORT_SYMBOL_GPL(sdev_evt_send);
2556 * sdev_evt_alloc - allocate a new scsi event
2557 * @evt_type: type of event to allocate
2558 * @gfpflags: GFP flags for allocation
2560 * Allocates and returns a new scsi_event.
2562 struct scsi_event *sdev_evt_alloc(enum scsi_device_event evt_type,
2565 struct scsi_event *evt = kzalloc(sizeof(struct scsi_event), gfpflags);
2569 evt->evt_type = evt_type;
2570 INIT_LIST_HEAD(&evt->node);
2572 /* evt_type-specific initialization, if any */
2574 case SDEV_EVT_MEDIA_CHANGE:
2575 case SDEV_EVT_INQUIRY_CHANGE_REPORTED:
2576 case SDEV_EVT_CAPACITY_CHANGE_REPORTED:
2577 case SDEV_EVT_SOFT_THRESHOLD_REACHED_REPORTED:
2578 case SDEV_EVT_MODE_PARAMETER_CHANGE_REPORTED:
2579 case SDEV_EVT_LUN_CHANGE_REPORTED:
2580 case SDEV_EVT_ALUA_STATE_CHANGE_REPORTED:
2581 case SDEV_EVT_POWER_ON_RESET_OCCURRED:
2589 EXPORT_SYMBOL_GPL(sdev_evt_alloc);
2592 * sdev_evt_send_simple - send asserted event to uevent thread
2593 * @sdev: scsi_device event occurred on
2594 * @evt_type: type of event to send
2595 * @gfpflags: GFP flags for allocation
2597 * Assert scsi device event asynchronously, given an event type.
2599 void sdev_evt_send_simple(struct scsi_device *sdev,
2600 enum scsi_device_event evt_type, gfp_t gfpflags)
2602 struct scsi_event *evt = sdev_evt_alloc(evt_type, gfpflags);
2604 sdev_printk(KERN_ERR, sdev, "event %d eaten due to OOM\n",
2609 sdev_evt_send(sdev, evt);
2611 EXPORT_SYMBOL_GPL(sdev_evt_send_simple);
2614 * scsi_device_quiesce - Block all commands except power management.
2615 * @sdev: scsi device to quiesce.
2617 * This works by trying to transition to the SDEV_QUIESCE state
2618 * (which must be a legal transition). When the device is in this
2619 * state, only power management requests will be accepted, all others will
2622 * Must be called with user context, may sleep.
2624 * Returns zero if unsuccessful or an error if not.
2627 scsi_device_quiesce(struct scsi_device *sdev)
2629 struct request_queue *q = sdev->request_queue;
2633 * It is allowed to call scsi_device_quiesce() multiple times from
2634 * the same context but concurrent scsi_device_quiesce() calls are
2637 WARN_ON_ONCE(sdev->quiesced_by && sdev->quiesced_by != current);
2639 if (sdev->quiesced_by == current)
2644 blk_mq_freeze_queue(q);
2646 * Ensure that the effect of blk_set_pm_only() will be visible
2647 * for percpu_ref_tryget() callers that occur after the queue
2648 * unfreeze even if the queue was already frozen before this function
2649 * was called. See also https://lwn.net/Articles/573497/.
2652 blk_mq_unfreeze_queue(q);
2654 mutex_lock(&sdev->state_mutex);
2655 err = scsi_device_set_state(sdev, SDEV_QUIESCE);
2657 sdev->quiesced_by = current;
2659 blk_clear_pm_only(q);
2660 mutex_unlock(&sdev->state_mutex);
2664 EXPORT_SYMBOL(scsi_device_quiesce);
2667 * scsi_device_resume - Restart user issued commands to a quiesced device.
2668 * @sdev: scsi device to resume.
2670 * Moves the device from quiesced back to running and restarts the
2673 * Must be called with user context, may sleep.
2675 void scsi_device_resume(struct scsi_device *sdev)
2677 /* check if the device state was mutated prior to resume, and if
2678 * so assume the state is being managed elsewhere (for example
2679 * device deleted during suspend)
2681 mutex_lock(&sdev->state_mutex);
2682 if (sdev->sdev_state == SDEV_QUIESCE)
2683 scsi_device_set_state(sdev, SDEV_RUNNING);
2684 if (sdev->quiesced_by) {
2685 sdev->quiesced_by = NULL;
2686 blk_clear_pm_only(sdev->request_queue);
2688 mutex_unlock(&sdev->state_mutex);
2690 EXPORT_SYMBOL(scsi_device_resume);
2693 device_quiesce_fn(struct scsi_device *sdev, void *data)
2695 scsi_device_quiesce(sdev);
2699 scsi_target_quiesce(struct scsi_target *starget)
2701 starget_for_each_device(starget, NULL, device_quiesce_fn);
2703 EXPORT_SYMBOL(scsi_target_quiesce);
2706 device_resume_fn(struct scsi_device *sdev, void *data)
2708 scsi_device_resume(sdev);
2712 scsi_target_resume(struct scsi_target *starget)
2714 starget_for_each_device(starget, NULL, device_resume_fn);
2716 EXPORT_SYMBOL(scsi_target_resume);
2718 static int __scsi_internal_device_block_nowait(struct scsi_device *sdev)
2720 if (scsi_device_set_state(sdev, SDEV_BLOCK))
2721 return scsi_device_set_state(sdev, SDEV_CREATED_BLOCK);
2726 void scsi_start_queue(struct scsi_device *sdev)
2728 if (cmpxchg(&sdev->queue_stopped, 1, 0))
2729 blk_mq_unquiesce_queue(sdev->request_queue);
2732 static void scsi_stop_queue(struct scsi_device *sdev)
2735 * The atomic variable of ->queue_stopped covers that
2736 * blk_mq_quiesce_queue* is balanced with blk_mq_unquiesce_queue.
2738 * The caller needs to wait until quiesce is done.
2740 if (!cmpxchg(&sdev->queue_stopped, 0, 1))
2741 blk_mq_quiesce_queue_nowait(sdev->request_queue);
2745 * scsi_internal_device_block_nowait - try to transition to the SDEV_BLOCK state
2746 * @sdev: device to block
2748 * Pause SCSI command processing on the specified device. Does not sleep.
2750 * Returns zero if successful or a negative error code upon failure.
2753 * This routine transitions the device to the SDEV_BLOCK state (which must be
2754 * a legal transition). When the device is in this state, command processing
2755 * is paused until the device leaves the SDEV_BLOCK state. See also
2756 * scsi_internal_device_unblock_nowait().
2758 int scsi_internal_device_block_nowait(struct scsi_device *sdev)
2760 int ret = __scsi_internal_device_block_nowait(sdev);
2763 * The device has transitioned to SDEV_BLOCK. Stop the
2764 * block layer from calling the midlayer with this device's
2768 scsi_stop_queue(sdev);
2771 EXPORT_SYMBOL_GPL(scsi_internal_device_block_nowait);
2774 * scsi_device_block - try to transition to the SDEV_BLOCK state
2775 * @sdev: device to block
2776 * @data: dummy argument, ignored
2778 * Pause SCSI command processing on the specified device. Callers must wait
2779 * until all ongoing scsi_queue_rq() calls have finished after this function
2783 * This routine transitions the device to the SDEV_BLOCK state (which must be
2784 * a legal transition). When the device is in this state, command processing
2785 * is paused until the device leaves the SDEV_BLOCK state. See also
2786 * scsi_internal_device_unblock().
2788 static void scsi_device_block(struct scsi_device *sdev, void *data)
2791 enum scsi_device_state state;
2793 mutex_lock(&sdev->state_mutex);
2794 err = __scsi_internal_device_block_nowait(sdev);
2795 state = sdev->sdev_state;
2798 * scsi_stop_queue() must be called with the state_mutex
2799 * held. Otherwise a simultaneous scsi_start_queue() call
2800 * might unquiesce the queue before we quiesce it.
2802 scsi_stop_queue(sdev);
2804 mutex_unlock(&sdev->state_mutex);
2806 WARN_ONCE(err, "%s: failed to block %s in state %d\n",
2807 __func__, dev_name(&sdev->sdev_gendev), state);
2811 * scsi_internal_device_unblock_nowait - resume a device after a block request
2812 * @sdev: device to resume
2813 * @new_state: state to set the device to after unblocking
2815 * Restart the device queue for a previously suspended SCSI device. Does not
2818 * Returns zero if successful or a negative error code upon failure.
2821 * This routine transitions the device to the SDEV_RUNNING state or to one of
2822 * the offline states (which must be a legal transition) allowing the midlayer
2823 * to goose the queue for this device.
2825 int scsi_internal_device_unblock_nowait(struct scsi_device *sdev,
2826 enum scsi_device_state new_state)
2828 switch (new_state) {
2830 case SDEV_TRANSPORT_OFFLINE:
2837 * Try to transition the scsi device to SDEV_RUNNING or one of the
2838 * offlined states and goose the device queue if successful.
2840 switch (sdev->sdev_state) {
2842 case SDEV_TRANSPORT_OFFLINE:
2843 sdev->sdev_state = new_state;
2845 case SDEV_CREATED_BLOCK:
2846 if (new_state == SDEV_TRANSPORT_OFFLINE ||
2847 new_state == SDEV_OFFLINE)
2848 sdev->sdev_state = new_state;
2850 sdev->sdev_state = SDEV_CREATED;
2858 scsi_start_queue(sdev);
2862 EXPORT_SYMBOL_GPL(scsi_internal_device_unblock_nowait);
2865 * scsi_internal_device_unblock - resume a device after a block request
2866 * @sdev: device to resume
2867 * @new_state: state to set the device to after unblocking
2869 * Restart the device queue for a previously suspended SCSI device. May sleep.
2871 * Returns zero if successful or a negative error code upon failure.
2874 * This routine transitions the device to the SDEV_RUNNING state or to one of
2875 * the offline states (which must be a legal transition) allowing the midlayer
2876 * to goose the queue for this device.
2878 static int scsi_internal_device_unblock(struct scsi_device *sdev,
2879 enum scsi_device_state new_state)
2883 mutex_lock(&sdev->state_mutex);
2884 ret = scsi_internal_device_unblock_nowait(sdev, new_state);
2885 mutex_unlock(&sdev->state_mutex);
2891 target_block(struct device *dev, void *data)
2893 if (scsi_is_target_device(dev))
2894 starget_for_each_device(to_scsi_target(dev), NULL,
2900 * scsi_block_targets - transition all SCSI child devices to SDEV_BLOCK state
2901 * @dev: a parent device of one or more scsi_target devices
2902 * @shost: the Scsi_Host to which this device belongs
2904 * Iterate over all children of @dev, which should be scsi_target devices,
2905 * and switch all subordinate scsi devices to SDEV_BLOCK state. Wait for
2906 * ongoing scsi_queue_rq() calls to finish. May sleep.
2909 * @dev must not itself be a scsi_target device.
2912 scsi_block_targets(struct Scsi_Host *shost, struct device *dev)
2914 WARN_ON_ONCE(scsi_is_target_device(dev));
2915 device_for_each_child(dev, NULL, target_block);
2916 blk_mq_wait_quiesce_done(&shost->tag_set);
2918 EXPORT_SYMBOL_GPL(scsi_block_targets);
2921 device_unblock(struct scsi_device *sdev, void *data)
2923 scsi_internal_device_unblock(sdev, *(enum scsi_device_state *)data);
2927 target_unblock(struct device *dev, void *data)
2929 if (scsi_is_target_device(dev))
2930 starget_for_each_device(to_scsi_target(dev), data,
2936 scsi_target_unblock(struct device *dev, enum scsi_device_state new_state)
2938 if (scsi_is_target_device(dev))
2939 starget_for_each_device(to_scsi_target(dev), &new_state,
2942 device_for_each_child(dev, &new_state, target_unblock);
2944 EXPORT_SYMBOL_GPL(scsi_target_unblock);
2947 * scsi_host_block - Try to transition all logical units to the SDEV_BLOCK state
2948 * @shost: device to block
2950 * Pause SCSI command processing for all logical units associated with the SCSI
2951 * host and wait until pending scsi_queue_rq() calls have finished.
2953 * Returns zero if successful or a negative error code upon failure.
2956 scsi_host_block(struct Scsi_Host *shost)
2958 struct scsi_device *sdev;
2962 * Call scsi_internal_device_block_nowait so we can avoid
2963 * calling synchronize_rcu() for each LUN.
2965 shost_for_each_device(sdev, shost) {
2966 mutex_lock(&sdev->state_mutex);
2967 ret = scsi_internal_device_block_nowait(sdev);
2968 mutex_unlock(&sdev->state_mutex);
2970 scsi_device_put(sdev);
2975 /* Wait for ongoing scsi_queue_rq() calls to finish. */
2976 blk_mq_wait_quiesce_done(&shost->tag_set);
2980 EXPORT_SYMBOL_GPL(scsi_host_block);
2983 scsi_host_unblock(struct Scsi_Host *shost, int new_state)
2985 struct scsi_device *sdev;
2988 shost_for_each_device(sdev, shost) {
2989 ret = scsi_internal_device_unblock(sdev, new_state);
2991 scsi_device_put(sdev);
2997 EXPORT_SYMBOL_GPL(scsi_host_unblock);
3000 * scsi_kmap_atomic_sg - find and atomically map an sg-elemnt
3001 * @sgl: scatter-gather list
3002 * @sg_count: number of segments in sg
3003 * @offset: offset in bytes into sg, on return offset into the mapped area
3004 * @len: bytes to map, on return number of bytes mapped
3006 * Returns virtual address of the start of the mapped page
3008 void *scsi_kmap_atomic_sg(struct scatterlist *sgl, int sg_count,
3009 size_t *offset, size_t *len)
3012 size_t sg_len = 0, len_complete = 0;
3013 struct scatterlist *sg;
3016 WARN_ON(!irqs_disabled());
3018 for_each_sg(sgl, sg, sg_count, i) {
3019 len_complete = sg_len; /* Complete sg-entries */
3020 sg_len += sg->length;
3021 if (sg_len > *offset)
3025 if (unlikely(i == sg_count)) {
3026 printk(KERN_ERR "%s: Bytes in sg: %zu, requested offset %zu, "
3028 __func__, sg_len, *offset, sg_count);
3033 /* Offset starting from the beginning of first page in this sg-entry */
3034 *offset = *offset - len_complete + sg->offset;
3036 /* Assumption: contiguous pages can be accessed as "page + i" */
3037 page = nth_page(sg_page(sg), (*offset >> PAGE_SHIFT));
3038 *offset &= ~PAGE_MASK;
3040 /* Bytes in this sg-entry from *offset to the end of the page */
3041 sg_len = PAGE_SIZE - *offset;
3045 return kmap_atomic(page);
3047 EXPORT_SYMBOL(scsi_kmap_atomic_sg);
3050 * scsi_kunmap_atomic_sg - atomically unmap a virtual address, previously mapped with scsi_kmap_atomic_sg
3051 * @virt: virtual address to be unmapped
3053 void scsi_kunmap_atomic_sg(void *virt)
3055 kunmap_atomic(virt);
3057 EXPORT_SYMBOL(scsi_kunmap_atomic_sg);
3059 void sdev_disable_disk_events(struct scsi_device *sdev)
3061 atomic_inc(&sdev->disk_events_disable_depth);
3063 EXPORT_SYMBOL(sdev_disable_disk_events);
3065 void sdev_enable_disk_events(struct scsi_device *sdev)
3067 if (WARN_ON_ONCE(atomic_read(&sdev->disk_events_disable_depth) <= 0))
3069 atomic_dec(&sdev->disk_events_disable_depth);
3071 EXPORT_SYMBOL(sdev_enable_disk_events);
3073 static unsigned char designator_prio(const unsigned char *d)
3076 /* not associated with LUN */
3080 /* invalid length */
3084 * Order of preference for lun descriptor:
3085 * - SCSI name string
3086 * - NAA IEEE Registered Extended
3087 * - EUI-64 based 16-byte
3088 * - EUI-64 based 12-byte
3089 * - NAA IEEE Registered
3090 * - NAA IEEE Extended
3091 * - EUI-64 based 8-byte
3092 * - SCSI name string (truncated)
3094 * as longer descriptors reduce the likelyhood
3095 * of identification clashes.
3098 switch (d[1] & 0xf) {
3100 /* SCSI name string, variable-length UTF-8 */
3103 switch (d[4] >> 4) {
3105 /* NAA registered extended */
3108 /* NAA registered */
3114 /* NAA locally assigned */
3123 /* EUI64-based, 16 byte */
3126 /* EUI64-based, 12 byte */
3129 /* EUI64-based, 8 byte */
3146 * scsi_vpd_lun_id - return a unique device identification
3147 * @sdev: SCSI device
3148 * @id: buffer for the identification
3149 * @id_len: length of the buffer
3151 * Copies a unique device identification into @id based
3152 * on the information in the VPD page 0x83 of the device.
3153 * The string will be formatted as a SCSI name string.
3155 * Returns the length of the identification or error on failure.
3156 * If the identifier is longer than the supplied buffer the actual
3157 * identifier length is returned and the buffer is not zero-padded.
3159 int scsi_vpd_lun_id(struct scsi_device *sdev, char *id, size_t id_len)
3163 const unsigned char *d, *cur_id_str;
3164 const struct scsi_vpd *vpd_pg83;
3165 int id_size = -EINVAL;
3168 vpd_pg83 = rcu_dereference(sdev->vpd_pg83);
3174 /* The id string must be at least 20 bytes + terminating NULL byte */
3180 memset(id, 0, id_len);
3181 for (d = vpd_pg83->data + 4;
3182 d < vpd_pg83->data + vpd_pg83->len;
3184 u8 prio = designator_prio(d);
3186 if (prio == 0 || cur_id_prio > prio)
3189 switch (d[1] & 0xf) {
3192 if (cur_id_size > d[3])
3196 if (cur_id_size + 4 > id_len)
3197 cur_id_size = id_len - 4;
3199 id_size = snprintf(id, id_len, "t10.%*pE",
3200 cur_id_size, cur_id_str);
3207 switch (cur_id_size) {
3209 id_size = snprintf(id, id_len,
3214 id_size = snprintf(id, id_len,
3219 id_size = snprintf(id, id_len,
3232 switch (cur_id_size) {
3234 id_size = snprintf(id, id_len,
3239 id_size = snprintf(id, id_len,
3248 /* SCSI name string */
3249 if (cur_id_size > d[3])
3251 /* Prefer others for truncated descriptor */
3252 if (d[3] > id_len) {
3254 if (cur_id_prio > prio)
3258 cur_id_size = id_size = d[3];
3260 if (cur_id_size >= id_len)
3261 cur_id_size = id_len - 1;
3262 memcpy(id, cur_id_str, cur_id_size);
3272 EXPORT_SYMBOL(scsi_vpd_lun_id);
3275 * scsi_vpd_tpg_id - return a target port group identifier
3276 * @sdev: SCSI device
3278 * Returns the Target Port Group identifier from the information
3279 * froom VPD page 0x83 of the device.
3281 * Returns the identifier or error on failure.
3283 int scsi_vpd_tpg_id(struct scsi_device *sdev, int *rel_id)
3285 const unsigned char *d;
3286 const struct scsi_vpd *vpd_pg83;
3287 int group_id = -EAGAIN, rel_port = -1;
3290 vpd_pg83 = rcu_dereference(sdev->vpd_pg83);
3296 d = vpd_pg83->data + 4;
3297 while (d < vpd_pg83->data + vpd_pg83->len) {
3298 switch (d[1] & 0xf) {
3300 /* Relative target port */
3301 rel_port = get_unaligned_be16(&d[6]);
3304 /* Target port group */
3305 group_id = get_unaligned_be16(&d[6]);
3314 if (group_id >= 0 && rel_id && rel_port != -1)
3319 EXPORT_SYMBOL(scsi_vpd_tpg_id);
3322 * scsi_build_sense - build sense data for a command
3323 * @scmd: scsi command for which the sense should be formatted
3324 * @desc: Sense format (non-zero == descriptor format,
3325 * 0 == fixed format)
3327 * @asc: Additional sense code
3328 * @ascq: Additional sense code qualifier
3331 void scsi_build_sense(struct scsi_cmnd *scmd, int desc, u8 key, u8 asc, u8 ascq)
3333 scsi_build_sense_buffer(desc, scmd->sense_buffer, key, asc, ascq);
3334 scmd->result = SAM_STAT_CHECK_CONDITION;
3336 EXPORT_SYMBOL_GPL(scsi_build_sense);