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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/ratelimit.h>
25#include <asm/unaligned.h>
26
27#include <scsi/scsi.h>
28#include <scsi/scsi_cmnd.h>
29#include <scsi/scsi_dbg.h>
30#include <scsi/scsi_device.h>
31#include <scsi/scsi_driver.h>
32#include <scsi/scsi_eh.h>
33#include <scsi/scsi_host.h>
34#include <scsi/scsi_transport.h>
35#include <scsi/scsi_dh.h>
36
37#include <trace/events/scsi.h>
38
39#include "scsi_debugfs.h"
40#include "scsi_priv.h"
41#include "scsi_logging.h"
42
43
44
45
46
47#ifdef CONFIG_ARCH_NO_SG_CHAIN
48#define SCSI_INLINE_PROT_SG_CNT 0
49#define SCSI_INLINE_SG_CNT 0
50#else
51#define SCSI_INLINE_PROT_SG_CNT 1
52#define SCSI_INLINE_SG_CNT 2
53#endif
54
55static struct kmem_cache *scsi_sense_cache;
56static DEFINE_MUTEX(scsi_sense_cache_mutex);
57
58static void scsi_mq_uninit_cmd(struct scsi_cmnd *cmd);
59
60int scsi_init_sense_cache(struct Scsi_Host *shost)
61{
62 int ret = 0;
63
64 mutex_lock(&scsi_sense_cache_mutex);
65 if (!scsi_sense_cache) {
66 scsi_sense_cache =
67 kmem_cache_create_usercopy("scsi_sense_cache",
68 SCSI_SENSE_BUFFERSIZE, 0, SLAB_HWCACHE_ALIGN,
69 0, SCSI_SENSE_BUFFERSIZE, NULL);
70 if (!scsi_sense_cache)
71 ret = -ENOMEM;
72 }
73 mutex_unlock(&scsi_sense_cache_mutex);
74 return ret;
75}
76
77
78
79
80
81
82#define SCSI_QUEUE_DELAY 3
83
84static void
85scsi_set_blocked(struct scsi_cmnd *cmd, int reason)
86{
87 struct Scsi_Host *host = cmd->device->host;
88 struct scsi_device *device = cmd->device;
89 struct scsi_target *starget = scsi_target(device);
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104 switch (reason) {
105 case SCSI_MLQUEUE_HOST_BUSY:
106 atomic_set(&host->host_blocked, host->max_host_blocked);
107 break;
108 case SCSI_MLQUEUE_DEVICE_BUSY:
109 case SCSI_MLQUEUE_EH_RETRY:
110 atomic_set(&device->device_blocked,
111 device->max_device_blocked);
112 break;
113 case SCSI_MLQUEUE_TARGET_BUSY:
114 atomic_set(&starget->target_blocked,
115 starget->max_target_blocked);
116 break;
117 }
118}
119
120static void scsi_mq_requeue_cmd(struct scsi_cmnd *cmd)
121{
122 struct request *rq = scsi_cmd_to_rq(cmd);
123
124 if (rq->rq_flags & RQF_DONTPREP) {
125 rq->rq_flags &= ~RQF_DONTPREP;
126 scsi_mq_uninit_cmd(cmd);
127 } else {
128 WARN_ON_ONCE(true);
129 }
130 blk_mq_requeue_request(rq, true);
131}
132
133
134
135
136
137
138
139
140
141
142
143
144
145static void __scsi_queue_insert(struct scsi_cmnd *cmd, int reason, bool unbusy)
146{
147 struct scsi_device *device = cmd->device;
148
149 SCSI_LOG_MLQUEUE(1, scmd_printk(KERN_INFO, cmd,
150 "Inserting command %p into mlqueue\n", cmd));
151
152 scsi_set_blocked(cmd, reason);
153
154
155
156
157
158 if (unbusy)
159 scsi_device_unbusy(device, cmd);
160
161
162
163
164
165
166
167 cmd->result = 0;
168
169 blk_mq_requeue_request(scsi_cmd_to_rq(cmd), true);
170}
171
172
173
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181
182
183
184void scsi_queue_insert(struct scsi_cmnd *cmd, int reason)
185{
186 __scsi_queue_insert(cmd, reason, true);
187}
188
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206
207
208int __scsi_execute(struct scsi_device *sdev, const unsigned char *cmd,
209 int data_direction, void *buffer, unsigned bufflen,
210 unsigned char *sense, struct scsi_sense_hdr *sshdr,
211 int timeout, int retries, u64 flags, req_flags_t rq_flags,
212 int *resid)
213{
214 struct request *req;
215 struct scsi_request *rq;
216 int ret;
217
218 req = blk_get_request(sdev->request_queue,
219 data_direction == DMA_TO_DEVICE ?
220 REQ_OP_DRV_OUT : REQ_OP_DRV_IN,
221 rq_flags & RQF_PM ? BLK_MQ_REQ_PM : 0);
222 if (IS_ERR(req))
223 return PTR_ERR(req);
224
225 rq = scsi_req(req);
226
227 if (bufflen) {
228 ret = blk_rq_map_kern(sdev->request_queue, req,
229 buffer, bufflen, GFP_NOIO);
230 if (ret)
231 goto out;
232 }
233 rq->cmd_len = COMMAND_SIZE(cmd[0]);
234 memcpy(rq->cmd, cmd, rq->cmd_len);
235 rq->retries = retries;
236 req->timeout = timeout;
237 req->cmd_flags |= flags;
238 req->rq_flags |= rq_flags | RQF_QUIET;
239
240
241
242
243 blk_execute_rq(NULL, req, 1);
244
245
246
247
248
249
250
251 if (unlikely(rq->resid_len > 0 && rq->resid_len <= bufflen))
252 memset(buffer + (bufflen - rq->resid_len), 0, rq->resid_len);
253
254 if (resid)
255 *resid = rq->resid_len;
256 if (sense && rq->sense_len)
257 memcpy(sense, rq->sense, SCSI_SENSE_BUFFERSIZE);
258 if (sshdr)
259 scsi_normalize_sense(rq->sense, rq->sense_len, sshdr);
260 ret = rq->result;
261 out:
262 blk_put_request(req);
263
264 return ret;
265}
266EXPORT_SYMBOL(__scsi_execute);
267
268
269
270
271
272
273
274
275
276
277static void scsi_dec_host_busy(struct Scsi_Host *shost, struct scsi_cmnd *cmd)
278{
279 unsigned long flags;
280
281 rcu_read_lock();
282 __clear_bit(SCMD_STATE_INFLIGHT, &cmd->state);
283 if (unlikely(scsi_host_in_recovery(shost))) {
284 spin_lock_irqsave(shost->host_lock, flags);
285 if (shost->host_failed || shost->host_eh_scheduled)
286 scsi_eh_wakeup(shost);
287 spin_unlock_irqrestore(shost->host_lock, flags);
288 }
289 rcu_read_unlock();
290}
291
292void scsi_device_unbusy(struct scsi_device *sdev, struct scsi_cmnd *cmd)
293{
294 struct Scsi_Host *shost = sdev->host;
295 struct scsi_target *starget = scsi_target(sdev);
296
297 scsi_dec_host_busy(shost, cmd);
298
299 if (starget->can_queue > 0)
300 atomic_dec(&starget->target_busy);
301
302 sbitmap_put(&sdev->budget_map, cmd->budget_token);
303 cmd->budget_token = -1;
304}
305
306static void scsi_kick_queue(struct request_queue *q)
307{
308 blk_mq_run_hw_queues(q, false);
309}
310
311
312
313
314
315
316
317
318static void scsi_single_lun_run(struct scsi_device *current_sdev)
319{
320 struct Scsi_Host *shost = current_sdev->host;
321 struct scsi_device *sdev, *tmp;
322 struct scsi_target *starget = scsi_target(current_sdev);
323 unsigned long flags;
324
325 spin_lock_irqsave(shost->host_lock, flags);
326 starget->starget_sdev_user = NULL;
327 spin_unlock_irqrestore(shost->host_lock, flags);
328
329
330
331
332
333
334
335 scsi_kick_queue(current_sdev->request_queue);
336
337 spin_lock_irqsave(shost->host_lock, flags);
338 if (starget->starget_sdev_user)
339 goto out;
340 list_for_each_entry_safe(sdev, tmp, &starget->devices,
341 same_target_siblings) {
342 if (sdev == current_sdev)
343 continue;
344 if (scsi_device_get(sdev))
345 continue;
346
347 spin_unlock_irqrestore(shost->host_lock, flags);
348 scsi_kick_queue(sdev->request_queue);
349 spin_lock_irqsave(shost->host_lock, flags);
350
351 scsi_device_put(sdev);
352 }
353 out:
354 spin_unlock_irqrestore(shost->host_lock, flags);
355}
356
357static inline bool scsi_device_is_busy(struct scsi_device *sdev)
358{
359 if (scsi_device_busy(sdev) >= sdev->queue_depth)
360 return true;
361 if (atomic_read(&sdev->device_blocked) > 0)
362 return true;
363 return false;
364}
365
366static inline bool scsi_target_is_busy(struct scsi_target *starget)
367{
368 if (starget->can_queue > 0) {
369 if (atomic_read(&starget->target_busy) >= starget->can_queue)
370 return true;
371 if (atomic_read(&starget->target_blocked) > 0)
372 return true;
373 }
374 return false;
375}
376
377static inline bool scsi_host_is_busy(struct Scsi_Host *shost)
378{
379 if (atomic_read(&shost->host_blocked) > 0)
380 return true;
381 if (shost->host_self_blocked)
382 return true;
383 return false;
384}
385
386static void scsi_starved_list_run(struct Scsi_Host *shost)
387{
388 LIST_HEAD(starved_list);
389 struct scsi_device *sdev;
390 unsigned long flags;
391
392 spin_lock_irqsave(shost->host_lock, flags);
393 list_splice_init(&shost->starved_list, &starved_list);
394
395 while (!list_empty(&starved_list)) {
396 struct request_queue *slq;
397
398
399
400
401
402
403
404
405
406
407
408 if (scsi_host_is_busy(shost))
409 break;
410
411 sdev = list_entry(starved_list.next,
412 struct scsi_device, starved_entry);
413 list_del_init(&sdev->starved_entry);
414 if (scsi_target_is_busy(scsi_target(sdev))) {
415 list_move_tail(&sdev->starved_entry,
416 &shost->starved_list);
417 continue;
418 }
419
420
421
422
423
424
425
426
427
428
429
430 slq = sdev->request_queue;
431 if (!blk_get_queue(slq))
432 continue;
433 spin_unlock_irqrestore(shost->host_lock, flags);
434
435 scsi_kick_queue(slq);
436 blk_put_queue(slq);
437
438 spin_lock_irqsave(shost->host_lock, flags);
439 }
440
441 list_splice(&starved_list, &shost->starved_list);
442 spin_unlock_irqrestore(shost->host_lock, flags);
443}
444
445
446
447
448
449
450
451static void scsi_run_queue(struct request_queue *q)
452{
453 struct scsi_device *sdev = q->queuedata;
454
455 if (scsi_target(sdev)->single_lun)
456 scsi_single_lun_run(sdev);
457 if (!list_empty(&sdev->host->starved_list))
458 scsi_starved_list_run(sdev->host);
459
460 blk_mq_run_hw_queues(q, false);
461}
462
463void scsi_requeue_run_queue(struct work_struct *work)
464{
465 struct scsi_device *sdev;
466 struct request_queue *q;
467
468 sdev = container_of(work, struct scsi_device, requeue_work);
469 q = sdev->request_queue;
470 scsi_run_queue(q);
471}
472
473void scsi_run_host_queues(struct Scsi_Host *shost)
474{
475 struct scsi_device *sdev;
476
477 shost_for_each_device(sdev, shost)
478 scsi_run_queue(sdev->request_queue);
479}
480
481static void scsi_uninit_cmd(struct scsi_cmnd *cmd)
482{
483 if (!blk_rq_is_passthrough(scsi_cmd_to_rq(cmd))) {
484 struct scsi_driver *drv = scsi_cmd_to_driver(cmd);
485
486 if (drv->uninit_command)
487 drv->uninit_command(cmd);
488 }
489}
490
491void scsi_free_sgtables(struct scsi_cmnd *cmd)
492{
493 if (cmd->sdb.table.nents)
494 sg_free_table_chained(&cmd->sdb.table,
495 SCSI_INLINE_SG_CNT);
496 if (scsi_prot_sg_count(cmd))
497 sg_free_table_chained(&cmd->prot_sdb->table,
498 SCSI_INLINE_PROT_SG_CNT);
499}
500EXPORT_SYMBOL_GPL(scsi_free_sgtables);
501
502static void scsi_mq_uninit_cmd(struct scsi_cmnd *cmd)
503{
504 scsi_free_sgtables(cmd);
505 scsi_uninit_cmd(cmd);
506}
507
508static void scsi_run_queue_async(struct scsi_device *sdev)
509{
510 if (scsi_target(sdev)->single_lun ||
511 !list_empty(&sdev->host->starved_list)) {
512 kblockd_schedule_work(&sdev->requeue_work);
513 } else {
514
515
516
517
518
519 int old = atomic_read(&sdev->restarts);
520
521
522
523
524
525
526
527
528
529 if (old && atomic_cmpxchg(&sdev->restarts, old, 0) == old)
530 blk_mq_run_hw_queues(sdev->request_queue, true);
531 }
532}
533
534
535static bool scsi_end_request(struct request *req, blk_status_t error,
536 unsigned int bytes)
537{
538 struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req);
539 struct scsi_device *sdev = cmd->device;
540 struct request_queue *q = sdev->request_queue;
541
542 if (blk_update_request(req, error, bytes))
543 return true;
544
545 if (blk_queue_add_random(q))
546 add_disk_randomness(req->rq_disk);
547
548 if (!blk_rq_is_passthrough(req)) {
549 WARN_ON_ONCE(!(cmd->flags & SCMD_INITIALIZED));
550 cmd->flags &= ~SCMD_INITIALIZED;
551 }
552
553
554
555
556
557
558
559 destroy_rcu_head(&cmd->rcu);
560
561
562
563
564
565
566
567
568 scsi_mq_uninit_cmd(cmd);
569
570
571
572
573
574 percpu_ref_get(&q->q_usage_counter);
575
576 __blk_mq_end_request(req, error);
577
578 scsi_run_queue_async(sdev);
579
580 percpu_ref_put(&q->q_usage_counter);
581 return false;
582}
583
584
585
586
587
588
589
590
591
592static blk_status_t scsi_result_to_blk_status(struct scsi_cmnd *cmd, int result)
593{
594 switch (host_byte(result)) {
595 case DID_OK:
596 if (scsi_status_is_good(result))
597 return BLK_STS_OK;
598 return BLK_STS_IOERR;
599 case DID_TRANSPORT_FAILFAST:
600 case DID_TRANSPORT_MARGINAL:
601 return BLK_STS_TRANSPORT;
602 case DID_TARGET_FAILURE:
603 set_host_byte(cmd, DID_OK);
604 return BLK_STS_TARGET;
605 case DID_NEXUS_FAILURE:
606 set_host_byte(cmd, DID_OK);
607 return BLK_STS_NEXUS;
608 case DID_ALLOC_FAILURE:
609 set_host_byte(cmd, DID_OK);
610 return BLK_STS_NOSPC;
611 case DID_MEDIUM_ERROR:
612 set_host_byte(cmd, DID_OK);
613 return BLK_STS_MEDIUM;
614 default:
615 return BLK_STS_IOERR;
616 }
617}
618
619
620static void scsi_io_completion_reprep(struct scsi_cmnd *cmd,
621 struct request_queue *q)
622{
623
624 scsi_mq_requeue_cmd(cmd);
625}
626
627static bool scsi_cmd_runtime_exceeced(struct scsi_cmnd *cmd)
628{
629 struct request *req = scsi_cmd_to_rq(cmd);
630 unsigned long wait_for;
631
632 if (cmd->allowed == SCSI_CMD_RETRIES_NO_LIMIT)
633 return false;
634
635 wait_for = (cmd->allowed + 1) * req->timeout;
636 if (time_before(cmd->jiffies_at_alloc + wait_for, jiffies)) {
637 scmd_printk(KERN_ERR, cmd, "timing out command, waited %lus\n",
638 wait_for/HZ);
639 return true;
640 }
641 return false;
642}
643
644
645static void scsi_io_completion_action(struct scsi_cmnd *cmd, int result)
646{
647 struct request_queue *q = cmd->device->request_queue;
648 struct request *req = scsi_cmd_to_rq(cmd);
649 int level = 0;
650 enum {ACTION_FAIL, ACTION_REPREP, ACTION_RETRY,
651 ACTION_DELAYED_RETRY} action;
652 struct scsi_sense_hdr sshdr;
653 bool sense_valid;
654 bool sense_current = true;
655 blk_status_t blk_stat;
656
657 sense_valid = scsi_command_normalize_sense(cmd, &sshdr);
658 if (sense_valid)
659 sense_current = !scsi_sense_is_deferred(&sshdr);
660
661 blk_stat = scsi_result_to_blk_status(cmd, result);
662
663 if (host_byte(result) == DID_RESET) {
664
665
666
667
668 action = ACTION_RETRY;
669 } else if (sense_valid && sense_current) {
670 switch (sshdr.sense_key) {
671 case UNIT_ATTENTION:
672 if (cmd->device->removable) {
673
674
675
676 cmd->device->changed = 1;
677 action = ACTION_FAIL;
678 } else {
679
680
681
682
683
684 action = ACTION_RETRY;
685 }
686 break;
687 case ILLEGAL_REQUEST:
688
689
690
691
692
693
694
695
696 if ((cmd->device->use_10_for_rw &&
697 sshdr.asc == 0x20 && sshdr.ascq == 0x00) &&
698 (cmd->cmnd[0] == READ_10 ||
699 cmd->cmnd[0] == WRITE_10)) {
700
701 cmd->device->use_10_for_rw = 0;
702 action = ACTION_REPREP;
703 } else if (sshdr.asc == 0x10) {
704 action = ACTION_FAIL;
705 blk_stat = BLK_STS_PROTECTION;
706
707 } else if (sshdr.asc == 0x20 || sshdr.asc == 0x24) {
708 action = ACTION_FAIL;
709 blk_stat = BLK_STS_TARGET;
710 } else
711 action = ACTION_FAIL;
712 break;
713 case ABORTED_COMMAND:
714 action = ACTION_FAIL;
715 if (sshdr.asc == 0x10)
716 blk_stat = BLK_STS_PROTECTION;
717 break;
718 case NOT_READY:
719
720
721
722 if (sshdr.asc == 0x04) {
723 switch (sshdr.ascq) {
724 case 0x01:
725 case 0x04:
726 case 0x05:
727 case 0x06:
728 case 0x07:
729 case 0x08:
730 case 0x09:
731 case 0x11:
732 case 0x14:
733 case 0x1a:
734 case 0x1b:
735 case 0x1d:
736 case 0x24:
737 action = ACTION_DELAYED_RETRY;
738 break;
739 case 0x0a:
740 blk_stat = BLK_STS_AGAIN;
741 fallthrough;
742 default:
743 action = ACTION_FAIL;
744 break;
745 }
746 } else
747 action = ACTION_FAIL;
748 break;
749 case VOLUME_OVERFLOW:
750
751 action = ACTION_FAIL;
752 break;
753 case DATA_PROTECT:
754 action = ACTION_FAIL;
755 if ((sshdr.asc == 0x0C && sshdr.ascq == 0x12) ||
756 (sshdr.asc == 0x55 &&
757 (sshdr.ascq == 0x0E || sshdr.ascq == 0x0F))) {
758
759 blk_stat = BLK_STS_ZONE_OPEN_RESOURCE;
760 }
761 break;
762 default:
763 action = ACTION_FAIL;
764 break;
765 }
766 } else
767 action = ACTION_FAIL;
768
769 if (action != ACTION_FAIL && scsi_cmd_runtime_exceeced(cmd))
770 action = ACTION_FAIL;
771
772 switch (action) {
773 case ACTION_FAIL:
774
775 if (!(req->rq_flags & RQF_QUIET)) {
776 static DEFINE_RATELIMIT_STATE(_rs,
777 DEFAULT_RATELIMIT_INTERVAL,
778 DEFAULT_RATELIMIT_BURST);
779
780 if (unlikely(scsi_logging_level))
781 level =
782 SCSI_LOG_LEVEL(SCSI_LOG_MLCOMPLETE_SHIFT,
783 SCSI_LOG_MLCOMPLETE_BITS);
784
785
786
787
788
789 if (!level && __ratelimit(&_rs)) {
790 scsi_print_result(cmd, NULL, FAILED);
791 if (sense_valid)
792 scsi_print_sense(cmd);
793 scsi_print_command(cmd);
794 }
795 }
796 if (!scsi_end_request(req, blk_stat, blk_rq_err_bytes(req)))
797 return;
798 fallthrough;
799 case ACTION_REPREP:
800 scsi_io_completion_reprep(cmd, q);
801 break;
802 case ACTION_RETRY:
803
804 __scsi_queue_insert(cmd, SCSI_MLQUEUE_EH_RETRY, false);
805 break;
806 case ACTION_DELAYED_RETRY:
807
808 __scsi_queue_insert(cmd, SCSI_MLQUEUE_DEVICE_BUSY, false);
809 break;
810 }
811}
812
813
814
815
816
817
818static int scsi_io_completion_nz_result(struct scsi_cmnd *cmd, int result,
819 blk_status_t *blk_statp)
820{
821 bool sense_valid;
822 bool sense_current = true;
823 struct request *req = scsi_cmd_to_rq(cmd);
824 struct scsi_sense_hdr sshdr;
825
826 sense_valid = scsi_command_normalize_sense(cmd, &sshdr);
827 if (sense_valid)
828 sense_current = !scsi_sense_is_deferred(&sshdr);
829
830 if (blk_rq_is_passthrough(req)) {
831 if (sense_valid) {
832
833
834
835 scsi_req(req)->sense_len =
836 min(8 + cmd->sense_buffer[7],
837 SCSI_SENSE_BUFFERSIZE);
838 }
839 if (sense_current)
840 *blk_statp = scsi_result_to_blk_status(cmd, result);
841 } else if (blk_rq_bytes(req) == 0 && sense_current) {
842
843
844
845
846
847 *blk_statp = scsi_result_to_blk_status(cmd, result);
848 }
849
850
851
852
853
854
855 if (sense_valid && (sshdr.sense_key == RECOVERED_ERROR)) {
856 bool do_print = true;
857
858
859
860
861
862 if ((sshdr.asc == 0x0) && (sshdr.ascq == 0x1d))
863 do_print = false;
864 else if (req->rq_flags & RQF_QUIET)
865 do_print = false;
866 if (do_print)
867 scsi_print_sense(cmd);
868 result = 0;
869
870 *blk_statp = BLK_STS_OK;
871 }
872
873
874
875
876
877
878
879 if ((result & 0xff) && scsi_status_is_good(result)) {
880 result = 0;
881 *blk_statp = BLK_STS_OK;
882 }
883 return result;
884}
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes)
909{
910 int result = cmd->result;
911 struct request_queue *q = cmd->device->request_queue;
912 struct request *req = scsi_cmd_to_rq(cmd);
913 blk_status_t blk_stat = BLK_STS_OK;
914
915 if (unlikely(result))
916 result = scsi_io_completion_nz_result(cmd, result, &blk_stat);
917
918 if (unlikely(blk_rq_is_passthrough(req))) {
919
920
921
922 scsi_req(req)->result = cmd->result;
923 }
924
925
926
927
928
929 SCSI_LOG_HLCOMPLETE(1, scmd_printk(KERN_INFO, cmd,
930 "%u sectors total, %d bytes done.\n",
931 blk_rq_sectors(req), good_bytes));
932
933
934
935
936
937 if (likely(blk_rq_bytes(req) > 0 || blk_stat == BLK_STS_OK)) {
938 if (likely(!scsi_end_request(req, blk_stat, good_bytes)))
939 return;
940 }
941
942
943 if (unlikely(blk_stat && scsi_noretry_cmd(cmd))) {
944 if (scsi_end_request(req, blk_stat, blk_rq_bytes(req)))
945 WARN_ONCE(true,
946 "Bytes remaining after failed, no-retry command");
947 return;
948 }
949
950
951
952
953
954 if (likely(result == 0))
955 scsi_io_completion_reprep(cmd, q);
956 else
957 scsi_io_completion_action(cmd, result);
958}
959
960static inline bool scsi_cmd_needs_dma_drain(struct scsi_device *sdev,
961 struct request *rq)
962{
963 return sdev->dma_drain_len && blk_rq_is_passthrough(rq) &&
964 !op_is_write(req_op(rq)) &&
965 sdev->host->hostt->dma_need_drain(rq);
966}
967
968
969
970
971
972
973
974
975
976
977
978
979
980blk_status_t scsi_alloc_sgtables(struct scsi_cmnd *cmd)
981{
982 struct scsi_device *sdev = cmd->device;
983 struct request *rq = scsi_cmd_to_rq(cmd);
984 unsigned short nr_segs = blk_rq_nr_phys_segments(rq);
985 struct scatterlist *last_sg = NULL;
986 blk_status_t ret;
987 bool need_drain = scsi_cmd_needs_dma_drain(sdev, rq);
988 int count;
989
990 if (WARN_ON_ONCE(!nr_segs))
991 return BLK_STS_IOERR;
992
993
994
995
996
997 if (need_drain)
998 nr_segs++;
999
1000
1001
1002
1003 if (unlikely(sg_alloc_table_chained(&cmd->sdb.table, nr_segs,
1004 cmd->sdb.table.sgl, SCSI_INLINE_SG_CNT)))
1005 return BLK_STS_RESOURCE;
1006
1007
1008
1009
1010
1011 count = __blk_rq_map_sg(rq->q, rq, cmd->sdb.table.sgl, &last_sg);
1012
1013 if (blk_rq_bytes(rq) & rq->q->dma_pad_mask) {
1014 unsigned int pad_len =
1015 (rq->q->dma_pad_mask & ~blk_rq_bytes(rq)) + 1;
1016
1017 last_sg->length += pad_len;
1018 cmd->extra_len += pad_len;
1019 }
1020
1021 if (need_drain) {
1022 sg_unmark_end(last_sg);
1023 last_sg = sg_next(last_sg);
1024 sg_set_buf(last_sg, sdev->dma_drain_buf, sdev->dma_drain_len);
1025 sg_mark_end(last_sg);
1026
1027 cmd->extra_len += sdev->dma_drain_len;
1028 count++;
1029 }
1030
1031 BUG_ON(count > cmd->sdb.table.nents);
1032 cmd->sdb.table.nents = count;
1033 cmd->sdb.length = blk_rq_payload_bytes(rq);
1034
1035 if (blk_integrity_rq(rq)) {
1036 struct scsi_data_buffer *prot_sdb = cmd->prot_sdb;
1037 int ivecs;
1038
1039 if (WARN_ON_ONCE(!prot_sdb)) {
1040
1041
1042
1043
1044
1045 ret = BLK_STS_IOERR;
1046 goto out_free_sgtables;
1047 }
1048
1049 ivecs = blk_rq_count_integrity_sg(rq->q, rq->bio);
1050
1051 if (sg_alloc_table_chained(&prot_sdb->table, ivecs,
1052 prot_sdb->table.sgl,
1053 SCSI_INLINE_PROT_SG_CNT)) {
1054 ret = BLK_STS_RESOURCE;
1055 goto out_free_sgtables;
1056 }
1057
1058 count = blk_rq_map_integrity_sg(rq->q, rq->bio,
1059 prot_sdb->table.sgl);
1060 BUG_ON(count > ivecs);
1061 BUG_ON(count > queue_max_integrity_segments(rq->q));
1062
1063 cmd->prot_sdb = prot_sdb;
1064 cmd->prot_sdb->table.nents = count;
1065 }
1066
1067 return BLK_STS_OK;
1068out_free_sgtables:
1069 scsi_free_sgtables(cmd);
1070 return ret;
1071}
1072EXPORT_SYMBOL(scsi_alloc_sgtables);
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085static void scsi_initialize_rq(struct request *rq)
1086{
1087 struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq);
1088 struct scsi_request *req = &cmd->req;
1089
1090 memset(req->__cmd, 0, sizeof(req->__cmd));
1091 req->cmd = req->__cmd;
1092 req->cmd_len = BLK_MAX_CDB;
1093 req->sense_len = 0;
1094
1095 init_rcu_head(&cmd->rcu);
1096 cmd->jiffies_at_alloc = jiffies;
1097 cmd->retries = 0;
1098}
1099
1100
1101
1102
1103
1104static void scsi_cleanup_rq(struct request *rq)
1105{
1106 if (rq->rq_flags & RQF_DONTPREP) {
1107 scsi_mq_uninit_cmd(blk_mq_rq_to_pdu(rq));
1108 rq->rq_flags &= ~RQF_DONTPREP;
1109 }
1110}
1111
1112
1113void scsi_init_command(struct scsi_device *dev, struct scsi_cmnd *cmd)
1114{
1115 void *buf = cmd->sense_buffer;
1116 void *prot = cmd->prot_sdb;
1117 struct request *rq = scsi_cmd_to_rq(cmd);
1118 unsigned int flags = cmd->flags & SCMD_PRESERVED_FLAGS;
1119 unsigned long jiffies_at_alloc;
1120 int retries, to_clear;
1121 bool in_flight;
1122 int budget_token = cmd->budget_token;
1123
1124 if (!blk_rq_is_passthrough(rq) && !(flags & SCMD_INITIALIZED)) {
1125 flags |= SCMD_INITIALIZED;
1126 scsi_initialize_rq(rq);
1127 }
1128
1129 jiffies_at_alloc = cmd->jiffies_at_alloc;
1130 retries = cmd->retries;
1131 in_flight = test_bit(SCMD_STATE_INFLIGHT, &cmd->state);
1132
1133
1134
1135
1136
1137 to_clear = sizeof(*cmd) - sizeof(cmd->req);
1138 if (!dev->host->hostt->init_cmd_priv)
1139 to_clear += dev->host->hostt->cmd_size;
1140 memset((char *)cmd + sizeof(cmd->req), 0, to_clear);
1141
1142 cmd->device = dev;
1143 cmd->sense_buffer = buf;
1144 cmd->prot_sdb = prot;
1145 cmd->flags = flags;
1146 INIT_DELAYED_WORK(&cmd->abort_work, scmd_eh_abort_handler);
1147 cmd->jiffies_at_alloc = jiffies_at_alloc;
1148 cmd->retries = retries;
1149 if (in_flight)
1150 __set_bit(SCMD_STATE_INFLIGHT, &cmd->state);
1151 cmd->budget_token = budget_token;
1152
1153}
1154
1155static blk_status_t scsi_setup_scsi_cmnd(struct scsi_device *sdev,
1156 struct request *req)
1157{
1158 struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req);
1159
1160
1161
1162
1163
1164
1165
1166 if (req->bio) {
1167 blk_status_t ret = scsi_alloc_sgtables(cmd);
1168 if (unlikely(ret != BLK_STS_OK))
1169 return ret;
1170 } else {
1171 BUG_ON(blk_rq_bytes(req));
1172
1173 memset(&cmd->sdb, 0, sizeof(cmd->sdb));
1174 }
1175
1176 cmd->cmd_len = scsi_req(req)->cmd_len;
1177 if (cmd->cmd_len == 0)
1178 cmd->cmd_len = scsi_command_size(cmd->cmnd);
1179 cmd->cmnd = scsi_req(req)->cmd;
1180 cmd->transfersize = blk_rq_bytes(req);
1181 cmd->allowed = scsi_req(req)->retries;
1182 return BLK_STS_OK;
1183}
1184
1185static blk_status_t
1186scsi_device_state_check(struct scsi_device *sdev, struct request *req)
1187{
1188 switch (sdev->sdev_state) {
1189 case SDEV_CREATED:
1190 return BLK_STS_OK;
1191 case SDEV_OFFLINE:
1192 case SDEV_TRANSPORT_OFFLINE:
1193
1194
1195
1196
1197
1198 if (!sdev->offline_already) {
1199 sdev->offline_already = true;
1200 sdev_printk(KERN_ERR, sdev,
1201 "rejecting I/O to offline device\n");
1202 }
1203 return BLK_STS_IOERR;
1204 case SDEV_DEL:
1205
1206
1207
1208
1209 sdev_printk(KERN_ERR, sdev,
1210 "rejecting I/O to dead device\n");
1211 return BLK_STS_IOERR;
1212 case SDEV_BLOCK:
1213 case SDEV_CREATED_BLOCK:
1214 return BLK_STS_RESOURCE;
1215 case SDEV_QUIESCE:
1216
1217
1218
1219
1220 if (req && WARN_ON_ONCE(!(req->rq_flags & RQF_PM)))
1221 return BLK_STS_RESOURCE;
1222 return BLK_STS_OK;
1223 default:
1224
1225
1226
1227
1228 if (req && !(req->rq_flags & RQF_PM))
1229 return BLK_STS_IOERR;
1230 return BLK_STS_OK;
1231 }
1232}
1233
1234
1235
1236
1237
1238static inline int scsi_dev_queue_ready(struct request_queue *q,
1239 struct scsi_device *sdev)
1240{
1241 int token;
1242
1243 token = sbitmap_get(&sdev->budget_map);
1244 if (atomic_read(&sdev->device_blocked)) {
1245 if (token < 0)
1246 goto out;
1247
1248 if (scsi_device_busy(sdev) > 1)
1249 goto out_dec;
1250
1251
1252
1253
1254 if (atomic_dec_return(&sdev->device_blocked) > 0)
1255 goto out_dec;
1256 SCSI_LOG_MLQUEUE(3, sdev_printk(KERN_INFO, sdev,
1257 "unblocking device at zero depth\n"));
1258 }
1259
1260 return token;
1261out_dec:
1262 if (token >= 0)
1263 sbitmap_put(&sdev->budget_map, token);
1264out:
1265 return -1;
1266}
1267
1268
1269
1270
1271
1272static inline int scsi_target_queue_ready(struct Scsi_Host *shost,
1273 struct scsi_device *sdev)
1274{
1275 struct scsi_target *starget = scsi_target(sdev);
1276 unsigned int busy;
1277
1278 if (starget->single_lun) {
1279 spin_lock_irq(shost->host_lock);
1280 if (starget->starget_sdev_user &&
1281 starget->starget_sdev_user != sdev) {
1282 spin_unlock_irq(shost->host_lock);
1283 return 0;
1284 }
1285 starget->starget_sdev_user = sdev;
1286 spin_unlock_irq(shost->host_lock);
1287 }
1288
1289 if (starget->can_queue <= 0)
1290 return 1;
1291
1292 busy = atomic_inc_return(&starget->target_busy) - 1;
1293 if (atomic_read(&starget->target_blocked) > 0) {
1294 if (busy)
1295 goto starved;
1296
1297
1298
1299
1300 if (atomic_dec_return(&starget->target_blocked) > 0)
1301 goto out_dec;
1302
1303 SCSI_LOG_MLQUEUE(3, starget_printk(KERN_INFO, starget,
1304 "unblocking target at zero depth\n"));
1305 }
1306
1307 if (busy >= starget->can_queue)
1308 goto starved;
1309
1310 return 1;
1311
1312starved:
1313 spin_lock_irq(shost->host_lock);
1314 list_move_tail(&sdev->starved_entry, &shost->starved_list);
1315 spin_unlock_irq(shost->host_lock);
1316out_dec:
1317 if (starget->can_queue > 0)
1318 atomic_dec(&starget->target_busy);
1319 return 0;
1320}
1321
1322
1323
1324
1325
1326
1327static inline int scsi_host_queue_ready(struct request_queue *q,
1328 struct Scsi_Host *shost,
1329 struct scsi_device *sdev,
1330 struct scsi_cmnd *cmd)
1331{
1332 if (scsi_host_in_recovery(shost))
1333 return 0;
1334
1335 if (atomic_read(&shost->host_blocked) > 0) {
1336 if (scsi_host_busy(shost) > 0)
1337 goto starved;
1338
1339
1340
1341
1342 if (atomic_dec_return(&shost->host_blocked) > 0)
1343 goto out_dec;
1344
1345 SCSI_LOG_MLQUEUE(3,
1346 shost_printk(KERN_INFO, shost,
1347 "unblocking host at zero depth\n"));
1348 }
1349
1350 if (shost->host_self_blocked)
1351 goto starved;
1352
1353
1354 if (!list_empty(&sdev->starved_entry)) {
1355 spin_lock_irq(shost->host_lock);
1356 if (!list_empty(&sdev->starved_entry))
1357 list_del_init(&sdev->starved_entry);
1358 spin_unlock_irq(shost->host_lock);
1359 }
1360
1361 __set_bit(SCMD_STATE_INFLIGHT, &cmd->state);
1362
1363 return 1;
1364
1365starved:
1366 spin_lock_irq(shost->host_lock);
1367 if (list_empty(&sdev->starved_entry))
1368 list_add_tail(&sdev->starved_entry, &shost->starved_list);
1369 spin_unlock_irq(shost->host_lock);
1370out_dec:
1371 scsi_dec_host_busy(shost, cmd);
1372 return 0;
1373}
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387static bool scsi_mq_lld_busy(struct request_queue *q)
1388{
1389 struct scsi_device *sdev = q->queuedata;
1390 struct Scsi_Host *shost;
1391
1392 if (blk_queue_dying(q))
1393 return false;
1394
1395 shost = sdev->host;
1396
1397
1398
1399
1400
1401
1402
1403 if (scsi_host_in_recovery(shost) || scsi_device_is_busy(sdev))
1404 return true;
1405
1406 return false;
1407}
1408
1409
1410
1411
1412
1413static void scsi_complete(struct request *rq)
1414{
1415 struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq);
1416 enum scsi_disposition disposition;
1417
1418 INIT_LIST_HEAD(&cmd->eh_entry);
1419
1420 atomic_inc(&cmd->device->iodone_cnt);
1421 if (cmd->result)
1422 atomic_inc(&cmd->device->ioerr_cnt);
1423
1424 disposition = scsi_decide_disposition(cmd);
1425 if (disposition != SUCCESS && scsi_cmd_runtime_exceeced(cmd))
1426 disposition = SUCCESS;
1427
1428 scsi_log_completion(cmd, disposition);
1429
1430 switch (disposition) {
1431 case SUCCESS:
1432 scsi_finish_command(cmd);
1433 break;
1434 case NEEDS_RETRY:
1435 scsi_queue_insert(cmd, SCSI_MLQUEUE_EH_RETRY);
1436 break;
1437 case ADD_TO_MLQUEUE:
1438 scsi_queue_insert(cmd, SCSI_MLQUEUE_DEVICE_BUSY);
1439 break;
1440 default:
1441 scsi_eh_scmd_add(cmd);
1442 break;
1443 }
1444}
1445
1446
1447
1448
1449
1450
1451
1452
1453static int scsi_dispatch_cmd(struct scsi_cmnd *cmd)
1454{
1455 struct Scsi_Host *host = cmd->device->host;
1456 int rtn = 0;
1457
1458 atomic_inc(&cmd->device->iorequest_cnt);
1459
1460
1461 if (unlikely(cmd->device->sdev_state == SDEV_DEL)) {
1462
1463
1464
1465 cmd->result = DID_NO_CONNECT << 16;
1466 goto done;
1467 }
1468
1469
1470 if (unlikely(scsi_device_blocked(cmd->device))) {
1471
1472
1473
1474
1475
1476
1477
1478 SCSI_LOG_MLQUEUE(3, scmd_printk(KERN_INFO, cmd,
1479 "queuecommand : device blocked\n"));
1480 return SCSI_MLQUEUE_DEVICE_BUSY;
1481 }
1482
1483
1484 if (cmd->device->lun_in_cdb)
1485 cmd->cmnd[1] = (cmd->cmnd[1] & 0x1f) |
1486 (cmd->device->lun << 5 & 0xe0);
1487
1488 scsi_log_send(cmd);
1489
1490
1491
1492
1493
1494 if (cmd->cmd_len > cmd->device->host->max_cmd_len) {
1495 SCSI_LOG_MLQUEUE(3, scmd_printk(KERN_INFO, cmd,
1496 "queuecommand : command too long. "
1497 "cdb_size=%d host->max_cmd_len=%d\n",
1498 cmd->cmd_len, cmd->device->host->max_cmd_len));
1499 cmd->result = (DID_ABORT << 16);
1500 goto done;
1501 }
1502
1503 if (unlikely(host->shost_state == SHOST_DEL)) {
1504 cmd->result = (DID_NO_CONNECT << 16);
1505 goto done;
1506
1507 }
1508
1509 trace_scsi_dispatch_cmd_start(cmd);
1510 rtn = host->hostt->queuecommand(host, cmd);
1511 if (rtn) {
1512 trace_scsi_dispatch_cmd_error(cmd, rtn);
1513 if (rtn != SCSI_MLQUEUE_DEVICE_BUSY &&
1514 rtn != SCSI_MLQUEUE_TARGET_BUSY)
1515 rtn = SCSI_MLQUEUE_HOST_BUSY;
1516
1517 SCSI_LOG_MLQUEUE(3, scmd_printk(KERN_INFO, cmd,
1518 "queuecommand : request rejected\n"));
1519 }
1520
1521 return rtn;
1522 done:
1523 cmd->scsi_done(cmd);
1524 return 0;
1525}
1526
1527
1528static unsigned int scsi_mq_inline_sgl_size(struct Scsi_Host *shost)
1529{
1530 return min_t(unsigned int, shost->sg_tablesize, SCSI_INLINE_SG_CNT) *
1531 sizeof(struct scatterlist);
1532}
1533
1534static blk_status_t scsi_prepare_cmd(struct request *req)
1535{
1536 struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req);
1537 struct scsi_device *sdev = req->q->queuedata;
1538 struct Scsi_Host *shost = sdev->host;
1539 struct scatterlist *sg;
1540
1541 scsi_init_command(sdev, cmd);
1542
1543 cmd->prot_op = SCSI_PROT_NORMAL;
1544 if (blk_rq_bytes(req))
1545 cmd->sc_data_direction = rq_dma_dir(req);
1546 else
1547 cmd->sc_data_direction = DMA_NONE;
1548
1549 sg = (void *)cmd + sizeof(struct scsi_cmnd) + shost->hostt->cmd_size;
1550 cmd->sdb.table.sgl = sg;
1551
1552 if (scsi_host_get_prot(shost)) {
1553 memset(cmd->prot_sdb, 0, sizeof(struct scsi_data_buffer));
1554
1555 cmd->prot_sdb->table.sgl =
1556 (struct scatterlist *)(cmd->prot_sdb + 1);
1557 }
1558
1559
1560
1561
1562
1563 if (blk_rq_is_passthrough(req))
1564 return scsi_setup_scsi_cmnd(sdev, req);
1565
1566 if (sdev->handler && sdev->handler->prep_fn) {
1567 blk_status_t ret = sdev->handler->prep_fn(sdev, req);
1568
1569 if (ret != BLK_STS_OK)
1570 return ret;
1571 }
1572
1573 cmd->cmnd = scsi_req(req)->cmd = scsi_req(req)->__cmd;
1574 memset(cmd->cmnd, 0, BLK_MAX_CDB);
1575 return scsi_cmd_to_driver(cmd)->init_command(cmd);
1576}
1577
1578static void scsi_mq_done(struct scsi_cmnd *cmd)
1579{
1580 if (unlikely(blk_should_fake_timeout(scsi_cmd_to_rq(cmd)->q)))
1581 return;
1582 if (unlikely(test_and_set_bit(SCMD_STATE_COMPLETE, &cmd->state)))
1583 return;
1584 trace_scsi_dispatch_cmd_done(cmd);
1585 blk_mq_complete_request(scsi_cmd_to_rq(cmd));
1586}
1587
1588static void scsi_mq_put_budget(struct request_queue *q, int budget_token)
1589{
1590 struct scsi_device *sdev = q->queuedata;
1591
1592 sbitmap_put(&sdev->budget_map, budget_token);
1593}
1594
1595static int scsi_mq_get_budget(struct request_queue *q)
1596{
1597 struct scsi_device *sdev = q->queuedata;
1598 int token = scsi_dev_queue_ready(q, sdev);
1599
1600 if (token >= 0)
1601 return token;
1602
1603 atomic_inc(&sdev->restarts);
1604
1605
1606
1607
1608
1609
1610 smp_mb__after_atomic();
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620 if (unlikely(scsi_device_busy(sdev) == 0 &&
1621 !scsi_device_blocked(sdev)))
1622 blk_mq_delay_run_hw_queues(sdev->request_queue, SCSI_QUEUE_DELAY);
1623 return -1;
1624}
1625
1626static void scsi_mq_set_rq_budget_token(struct request *req, int token)
1627{
1628 struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req);
1629
1630 cmd->budget_token = token;
1631}
1632
1633static int scsi_mq_get_rq_budget_token(struct request *req)
1634{
1635 struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req);
1636
1637 return cmd->budget_token;
1638}
1639
1640static blk_status_t scsi_queue_rq(struct blk_mq_hw_ctx *hctx,
1641 const struct blk_mq_queue_data *bd)
1642{
1643 struct request *req = bd->rq;
1644 struct request_queue *q = req->q;
1645 struct scsi_device *sdev = q->queuedata;
1646 struct Scsi_Host *shost = sdev->host;
1647 struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req);
1648 blk_status_t ret;
1649 int reason;
1650
1651 WARN_ON_ONCE(cmd->budget_token < 0);
1652
1653
1654
1655
1656
1657 if (unlikely(sdev->sdev_state != SDEV_RUNNING)) {
1658 ret = scsi_device_state_check(sdev, req);
1659 if (ret != BLK_STS_OK)
1660 goto out_put_budget;
1661 }
1662
1663 ret = BLK_STS_RESOURCE;
1664 if (!scsi_target_queue_ready(shost, sdev))
1665 goto out_put_budget;
1666 if (!scsi_host_queue_ready(q, shost, sdev, cmd))
1667 goto out_dec_target_busy;
1668
1669 if (!(req->rq_flags & RQF_DONTPREP)) {
1670 ret = scsi_prepare_cmd(req);
1671 if (ret != BLK_STS_OK)
1672 goto out_dec_host_busy;
1673 req->rq_flags |= RQF_DONTPREP;
1674 } else {
1675 clear_bit(SCMD_STATE_COMPLETE, &cmd->state);
1676 }
1677
1678 cmd->flags &= SCMD_PRESERVED_FLAGS;
1679 if (sdev->simple_tags)
1680 cmd->flags |= SCMD_TAGGED;
1681 if (bd->last)
1682 cmd->flags |= SCMD_LAST;
1683
1684 scsi_set_resid(cmd, 0);
1685 memset(cmd->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE);
1686 cmd->scsi_done = scsi_mq_done;
1687
1688 blk_mq_start_request(req);
1689 reason = scsi_dispatch_cmd(cmd);
1690 if (reason) {
1691 scsi_set_blocked(cmd, reason);
1692 ret = BLK_STS_RESOURCE;
1693 goto out_dec_host_busy;
1694 }
1695
1696 return BLK_STS_OK;
1697
1698out_dec_host_busy:
1699 scsi_dec_host_busy(shost, cmd);
1700out_dec_target_busy:
1701 if (scsi_target(sdev)->can_queue > 0)
1702 atomic_dec(&scsi_target(sdev)->target_busy);
1703out_put_budget:
1704 scsi_mq_put_budget(q, cmd->budget_token);
1705 cmd->budget_token = -1;
1706 switch (ret) {
1707 case BLK_STS_OK:
1708 break;
1709 case BLK_STS_RESOURCE:
1710 case BLK_STS_ZONE_RESOURCE:
1711 if (scsi_device_blocked(sdev))
1712 ret = BLK_STS_DEV_RESOURCE;
1713 break;
1714 case BLK_STS_AGAIN:
1715 scsi_req(req)->result = DID_BUS_BUSY << 16;
1716 if (req->rq_flags & RQF_DONTPREP)
1717 scsi_mq_uninit_cmd(cmd);
1718 break;
1719 default:
1720 if (unlikely(!scsi_device_online(sdev)))
1721 scsi_req(req)->result = DID_NO_CONNECT << 16;
1722 else
1723 scsi_req(req)->result = DID_ERROR << 16;
1724
1725
1726
1727
1728
1729 if (req->rq_flags & RQF_DONTPREP)
1730 scsi_mq_uninit_cmd(cmd);
1731 scsi_run_queue_async(sdev);
1732 break;
1733 }
1734 return ret;
1735}
1736
1737static enum blk_eh_timer_return scsi_timeout(struct request *req,
1738 bool reserved)
1739{
1740 if (reserved)
1741 return BLK_EH_RESET_TIMER;
1742 return scsi_times_out(req);
1743}
1744
1745static int scsi_mq_init_request(struct blk_mq_tag_set *set, struct request *rq,
1746 unsigned int hctx_idx, unsigned int numa_node)
1747{
1748 struct Scsi_Host *shost = set->driver_data;
1749 struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq);
1750 struct scatterlist *sg;
1751 int ret = 0;
1752
1753 cmd->sense_buffer =
1754 kmem_cache_alloc_node(scsi_sense_cache, GFP_KERNEL, numa_node);
1755 if (!cmd->sense_buffer)
1756 return -ENOMEM;
1757 cmd->req.sense = cmd->sense_buffer;
1758
1759 if (scsi_host_get_prot(shost)) {
1760 sg = (void *)cmd + sizeof(struct scsi_cmnd) +
1761 shost->hostt->cmd_size;
1762 cmd->prot_sdb = (void *)sg + scsi_mq_inline_sgl_size(shost);
1763 }
1764
1765 if (shost->hostt->init_cmd_priv) {
1766 ret = shost->hostt->init_cmd_priv(shost, cmd);
1767 if (ret < 0)
1768 kmem_cache_free(scsi_sense_cache, cmd->sense_buffer);
1769 }
1770
1771 return ret;
1772}
1773
1774static void scsi_mq_exit_request(struct blk_mq_tag_set *set, struct request *rq,
1775 unsigned int hctx_idx)
1776{
1777 struct Scsi_Host *shost = set->driver_data;
1778 struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq);
1779
1780 if (shost->hostt->exit_cmd_priv)
1781 shost->hostt->exit_cmd_priv(shost, cmd);
1782 kmem_cache_free(scsi_sense_cache, cmd->sense_buffer);
1783}
1784
1785
1786static int scsi_mq_poll(struct blk_mq_hw_ctx *hctx)
1787{
1788 struct Scsi_Host *shost = hctx->driver_data;
1789
1790 if (shost->hostt->mq_poll)
1791 return shost->hostt->mq_poll(shost, hctx->queue_num);
1792
1793 return 0;
1794}
1795
1796static int scsi_init_hctx(struct blk_mq_hw_ctx *hctx, void *data,
1797 unsigned int hctx_idx)
1798{
1799 struct Scsi_Host *shost = data;
1800
1801 hctx->driver_data = shost;
1802 return 0;
1803}
1804
1805static int scsi_map_queues(struct blk_mq_tag_set *set)
1806{
1807 struct Scsi_Host *shost = container_of(set, struct Scsi_Host, tag_set);
1808
1809 if (shost->hostt->map_queues)
1810 return shost->hostt->map_queues(shost);
1811 return blk_mq_map_queues(&set->map[HCTX_TYPE_DEFAULT]);
1812}
1813
1814void __scsi_init_queue(struct Scsi_Host *shost, struct request_queue *q)
1815{
1816 struct device *dev = shost->dma_dev;
1817
1818
1819
1820
1821 blk_queue_max_segments(q, min_t(unsigned short, shost->sg_tablesize,
1822 SG_MAX_SEGMENTS));
1823
1824 if (scsi_host_prot_dma(shost)) {
1825 shost->sg_prot_tablesize =
1826 min_not_zero(shost->sg_prot_tablesize,
1827 (unsigned short)SCSI_MAX_PROT_SG_SEGMENTS);
1828 BUG_ON(shost->sg_prot_tablesize < shost->sg_tablesize);
1829 blk_queue_max_integrity_segments(q, shost->sg_prot_tablesize);
1830 }
1831
1832 if (dev->dma_mask) {
1833 shost->max_sectors = min_t(unsigned int, shost->max_sectors,
1834 dma_max_mapping_size(dev) >> SECTOR_SHIFT);
1835 }
1836 blk_queue_max_hw_sectors(q, shost->max_sectors);
1837 blk_queue_segment_boundary(q, shost->dma_boundary);
1838 dma_set_seg_boundary(dev, shost->dma_boundary);
1839
1840 blk_queue_max_segment_size(q, shost->max_segment_size);
1841 blk_queue_virt_boundary(q, shost->virt_boundary_mask);
1842 dma_set_max_seg_size(dev, queue_max_segment_size(q));
1843
1844
1845
1846
1847
1848
1849
1850
1851 blk_queue_dma_alignment(q, max(4, dma_get_cache_alignment()) - 1);
1852}
1853EXPORT_SYMBOL_GPL(__scsi_init_queue);
1854
1855static const struct blk_mq_ops scsi_mq_ops_no_commit = {
1856 .get_budget = scsi_mq_get_budget,
1857 .put_budget = scsi_mq_put_budget,
1858 .queue_rq = scsi_queue_rq,
1859 .complete = scsi_complete,
1860 .timeout = scsi_timeout,
1861#ifdef CONFIG_BLK_DEBUG_FS
1862 .show_rq = scsi_show_rq,
1863#endif
1864 .init_request = scsi_mq_init_request,
1865 .exit_request = scsi_mq_exit_request,
1866 .initialize_rq_fn = scsi_initialize_rq,
1867 .cleanup_rq = scsi_cleanup_rq,
1868 .busy = scsi_mq_lld_busy,
1869 .map_queues = scsi_map_queues,
1870 .init_hctx = scsi_init_hctx,
1871 .poll = scsi_mq_poll,
1872 .set_rq_budget_token = scsi_mq_set_rq_budget_token,
1873 .get_rq_budget_token = scsi_mq_get_rq_budget_token,
1874};
1875
1876
1877static void scsi_commit_rqs(struct blk_mq_hw_ctx *hctx)
1878{
1879 struct Scsi_Host *shost = hctx->driver_data;
1880
1881 shost->hostt->commit_rqs(shost, hctx->queue_num);
1882}
1883
1884static const struct blk_mq_ops scsi_mq_ops = {
1885 .get_budget = scsi_mq_get_budget,
1886 .put_budget = scsi_mq_put_budget,
1887 .queue_rq = scsi_queue_rq,
1888 .commit_rqs = scsi_commit_rqs,
1889 .complete = scsi_complete,
1890 .timeout = scsi_timeout,
1891#ifdef CONFIG_BLK_DEBUG_FS
1892 .show_rq = scsi_show_rq,
1893#endif
1894 .init_request = scsi_mq_init_request,
1895 .exit_request = scsi_mq_exit_request,
1896 .initialize_rq_fn = scsi_initialize_rq,
1897 .cleanup_rq = scsi_cleanup_rq,
1898 .busy = scsi_mq_lld_busy,
1899 .map_queues = scsi_map_queues,
1900 .init_hctx = scsi_init_hctx,
1901 .poll = scsi_mq_poll,
1902 .set_rq_budget_token = scsi_mq_set_rq_budget_token,
1903 .get_rq_budget_token = scsi_mq_get_rq_budget_token,
1904};
1905
1906int scsi_mq_setup_tags(struct Scsi_Host *shost)
1907{
1908 unsigned int cmd_size, sgl_size;
1909 struct blk_mq_tag_set *tag_set = &shost->tag_set;
1910
1911 sgl_size = max_t(unsigned int, sizeof(struct scatterlist),
1912 scsi_mq_inline_sgl_size(shost));
1913 cmd_size = sizeof(struct scsi_cmnd) + shost->hostt->cmd_size + sgl_size;
1914 if (scsi_host_get_prot(shost))
1915 cmd_size += sizeof(struct scsi_data_buffer) +
1916 sizeof(struct scatterlist) * SCSI_INLINE_PROT_SG_CNT;
1917
1918 memset(tag_set, 0, sizeof(*tag_set));
1919 if (shost->hostt->commit_rqs)
1920 tag_set->ops = &scsi_mq_ops;
1921 else
1922 tag_set->ops = &scsi_mq_ops_no_commit;
1923 tag_set->nr_hw_queues = shost->nr_hw_queues ? : 1;
1924 tag_set->nr_maps = shost->nr_maps ? : 1;
1925 tag_set->queue_depth = shost->can_queue;
1926 tag_set->cmd_size = cmd_size;
1927 tag_set->numa_node = NUMA_NO_NODE;
1928 tag_set->flags = BLK_MQ_F_SHOULD_MERGE;
1929 tag_set->flags |=
1930 BLK_ALLOC_POLICY_TO_MQ_FLAG(shost->hostt->tag_alloc_policy);
1931 tag_set->driver_data = shost;
1932 if (shost->host_tagset)
1933 tag_set->flags |= BLK_MQ_F_TAG_HCTX_SHARED;
1934
1935 return blk_mq_alloc_tag_set(tag_set);
1936}
1937
1938void scsi_mq_destroy_tags(struct Scsi_Host *shost)
1939{
1940 blk_mq_free_tag_set(&shost->tag_set);
1941}
1942
1943
1944
1945
1946
1947
1948
1949
1950struct scsi_device *scsi_device_from_queue(struct request_queue *q)
1951{
1952 struct scsi_device *sdev = NULL;
1953
1954 if (q->mq_ops == &scsi_mq_ops_no_commit ||
1955 q->mq_ops == &scsi_mq_ops)
1956 sdev = q->queuedata;
1957 if (!sdev || !get_device(&sdev->sdev_gendev))
1958 sdev = NULL;
1959
1960 return sdev;
1961}
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971void scsi_block_requests(struct Scsi_Host *shost)
1972{
1973 shost->host_self_blocked = 1;
1974}
1975EXPORT_SYMBOL(scsi_block_requests);
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987void scsi_unblock_requests(struct Scsi_Host *shost)
1988{
1989 shost->host_self_blocked = 0;
1990 scsi_run_host_queues(shost);
1991}
1992EXPORT_SYMBOL(scsi_unblock_requests);
1993
1994void scsi_exit_queue(void)
1995{
1996 kmem_cache_destroy(scsi_sense_cache);
1997}
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017int
2018scsi_mode_select(struct scsi_device *sdev, int pf, int sp, int modepage,
2019 unsigned char *buffer, int len, int timeout, int retries,
2020 struct scsi_mode_data *data, struct scsi_sense_hdr *sshdr)
2021{
2022 unsigned char cmd[10];
2023 unsigned char *real_buffer;
2024 int ret;
2025
2026 memset(cmd, 0, sizeof(cmd));
2027 cmd[1] = (pf ? 0x10 : 0) | (sp ? 0x01 : 0);
2028
2029 if (sdev->use_10_for_ms) {
2030 if (len > 65535)
2031 return -EINVAL;
2032 real_buffer = kmalloc(8 + len, GFP_KERNEL);
2033 if (!real_buffer)
2034 return -ENOMEM;
2035 memcpy(real_buffer + 8, buffer, len);
2036 len += 8;
2037 real_buffer[0] = 0;
2038 real_buffer[1] = 0;
2039 real_buffer[2] = data->medium_type;
2040 real_buffer[3] = data->device_specific;
2041 real_buffer[4] = data->longlba ? 0x01 : 0;
2042 real_buffer[5] = 0;
2043 real_buffer[6] = data->block_descriptor_length >> 8;
2044 real_buffer[7] = data->block_descriptor_length;
2045
2046 cmd[0] = MODE_SELECT_10;
2047 cmd[7] = len >> 8;
2048 cmd[8] = len;
2049 } else {
2050 if (len > 255 || data->block_descriptor_length > 255 ||
2051 data->longlba)
2052 return -EINVAL;
2053
2054 real_buffer = kmalloc(4 + len, GFP_KERNEL);
2055 if (!real_buffer)
2056 return -ENOMEM;
2057 memcpy(real_buffer + 4, buffer, len);
2058 len += 4;
2059 real_buffer[0] = 0;
2060 real_buffer[1] = data->medium_type;
2061 real_buffer[2] = data->device_specific;
2062 real_buffer[3] = data->block_descriptor_length;
2063
2064 cmd[0] = MODE_SELECT;
2065 cmd[4] = len;
2066 }
2067
2068 ret = scsi_execute_req(sdev, cmd, DMA_TO_DEVICE, real_buffer, len,
2069 sshdr, timeout, retries, NULL);
2070 kfree(real_buffer);
2071 return ret;
2072}
2073EXPORT_SYMBOL_GPL(scsi_mode_select);
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090int
2091scsi_mode_sense(struct scsi_device *sdev, int dbd, int modepage,
2092 unsigned char *buffer, int len, int timeout, int retries,
2093 struct scsi_mode_data *data, struct scsi_sense_hdr *sshdr)
2094{
2095 unsigned char cmd[12];
2096 int use_10_for_ms;
2097 int header_length;
2098 int result, retry_count = retries;
2099 struct scsi_sense_hdr my_sshdr;
2100
2101 memset(data, 0, sizeof(*data));
2102 memset(&cmd[0], 0, 12);
2103
2104 dbd = sdev->set_dbd_for_ms ? 8 : dbd;
2105 cmd[1] = dbd & 0x18;
2106 cmd[2] = modepage;
2107
2108
2109 if (!sshdr)
2110 sshdr = &my_sshdr;
2111
2112 retry:
2113 use_10_for_ms = sdev->use_10_for_ms;
2114
2115 if (use_10_for_ms) {
2116 if (len < 8)
2117 len = 8;
2118
2119 cmd[0] = MODE_SENSE_10;
2120 cmd[8] = len;
2121 header_length = 8;
2122 } else {
2123 if (len < 4)
2124 len = 4;
2125
2126 cmd[0] = MODE_SENSE;
2127 cmd[4] = len;
2128 header_length = 4;
2129 }
2130
2131 memset(buffer, 0, len);
2132
2133 result = scsi_execute_req(sdev, cmd, DMA_FROM_DEVICE, buffer, len,
2134 sshdr, timeout, retries, NULL);
2135 if (result < 0)
2136 return result;
2137
2138
2139
2140
2141
2142
2143 if (!scsi_status_is_good(result)) {
2144 if (scsi_sense_valid(sshdr)) {
2145 if ((sshdr->sense_key == ILLEGAL_REQUEST) &&
2146 (sshdr->asc == 0x20) && (sshdr->ascq == 0)) {
2147
2148
2149
2150 if (use_10_for_ms) {
2151 sdev->use_10_for_ms = 0;
2152 goto retry;
2153 }
2154 }
2155 if (scsi_status_is_check_condition(result) &&
2156 sshdr->sense_key == UNIT_ATTENTION &&
2157 retry_count) {
2158 retry_count--;
2159 goto retry;
2160 }
2161 }
2162 return -EIO;
2163 }
2164 if (unlikely(buffer[0] == 0x86 && buffer[1] == 0x0b &&
2165 (modepage == 6 || modepage == 8))) {
2166
2167 header_length = 0;
2168 data->length = 13;
2169 data->medium_type = 0;
2170 data->device_specific = 0;
2171 data->longlba = 0;
2172 data->block_descriptor_length = 0;
2173 } else if (use_10_for_ms) {
2174 data->length = buffer[0]*256 + buffer[1] + 2;
2175 data->medium_type = buffer[2];
2176 data->device_specific = buffer[3];
2177 data->longlba = buffer[4] & 0x01;
2178 data->block_descriptor_length = buffer[6]*256
2179 + buffer[7];
2180 } else {
2181 data->length = buffer[0] + 1;
2182 data->medium_type = buffer[1];
2183 data->device_specific = buffer[2];
2184 data->block_descriptor_length = buffer[3];
2185 }
2186 data->header_length = header_length;
2187
2188 return 0;
2189}
2190EXPORT_SYMBOL(scsi_mode_sense);
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202int
2203scsi_test_unit_ready(struct scsi_device *sdev, int timeout, int retries,
2204 struct scsi_sense_hdr *sshdr)
2205{
2206 char cmd[] = {
2207 TEST_UNIT_READY, 0, 0, 0, 0, 0,
2208 };
2209 int result;
2210
2211
2212 do {
2213 result = scsi_execute_req(sdev, cmd, DMA_NONE, NULL, 0, sshdr,
2214 timeout, 1, NULL);
2215 if (sdev->removable && scsi_sense_valid(sshdr) &&
2216 sshdr->sense_key == UNIT_ATTENTION)
2217 sdev->changed = 1;
2218 } while (scsi_sense_valid(sshdr) &&
2219 sshdr->sense_key == UNIT_ATTENTION && --retries);
2220
2221 return result;
2222}
2223EXPORT_SYMBOL(scsi_test_unit_ready);
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233int
2234scsi_device_set_state(struct scsi_device *sdev, enum scsi_device_state state)
2235{
2236 enum scsi_device_state oldstate = sdev->sdev_state;
2237
2238 if (state == oldstate)
2239 return 0;
2240
2241 switch (state) {
2242 case SDEV_CREATED:
2243 switch (oldstate) {
2244 case SDEV_CREATED_BLOCK:
2245 break;
2246 default:
2247 goto illegal;
2248 }
2249 break;
2250
2251 case SDEV_RUNNING:
2252 switch (oldstate) {
2253 case SDEV_CREATED:
2254 case SDEV_OFFLINE:
2255 case SDEV_TRANSPORT_OFFLINE:
2256 case SDEV_QUIESCE:
2257 case SDEV_BLOCK:
2258 break;
2259 default:
2260 goto illegal;
2261 }
2262 break;
2263
2264 case SDEV_QUIESCE:
2265 switch (oldstate) {
2266 case SDEV_RUNNING:
2267 case SDEV_OFFLINE:
2268 case SDEV_TRANSPORT_OFFLINE:
2269 break;
2270 default:
2271 goto illegal;
2272 }
2273 break;
2274
2275 case SDEV_OFFLINE:
2276 case SDEV_TRANSPORT_OFFLINE:
2277 switch (oldstate) {
2278 case SDEV_CREATED:
2279 case SDEV_RUNNING:
2280 case SDEV_QUIESCE:
2281 case SDEV_BLOCK:
2282 break;
2283 default:
2284 goto illegal;
2285 }
2286 break;
2287
2288 case SDEV_BLOCK:
2289 switch (oldstate) {
2290 case SDEV_RUNNING:
2291 case SDEV_CREATED_BLOCK:
2292 case SDEV_QUIESCE:
2293 case SDEV_OFFLINE:
2294 break;
2295 default:
2296 goto illegal;
2297 }
2298 break;
2299
2300 case SDEV_CREATED_BLOCK:
2301 switch (oldstate) {
2302 case SDEV_CREATED:
2303 break;
2304 default:
2305 goto illegal;
2306 }
2307 break;
2308
2309 case SDEV_CANCEL:
2310 switch (oldstate) {
2311 case SDEV_CREATED:
2312 case SDEV_RUNNING:
2313 case SDEV_QUIESCE:
2314 case SDEV_OFFLINE:
2315 case SDEV_TRANSPORT_OFFLINE:
2316 break;
2317 default:
2318 goto illegal;
2319 }
2320 break;
2321
2322 case SDEV_DEL:
2323 switch (oldstate) {
2324 case SDEV_CREATED:
2325 case SDEV_RUNNING:
2326 case SDEV_OFFLINE:
2327 case SDEV_TRANSPORT_OFFLINE:
2328 case SDEV_CANCEL:
2329 case SDEV_BLOCK:
2330 case SDEV_CREATED_BLOCK:
2331 break;
2332 default:
2333 goto illegal;
2334 }
2335 break;
2336
2337 }
2338 sdev->offline_already = false;
2339 sdev->sdev_state = state;
2340 return 0;
2341
2342 illegal:
2343 SCSI_LOG_ERROR_RECOVERY(1,
2344 sdev_printk(KERN_ERR, sdev,
2345 "Illegal state transition %s->%s",
2346 scsi_device_state_name(oldstate),
2347 scsi_device_state_name(state))
2348 );
2349 return -EINVAL;
2350}
2351EXPORT_SYMBOL(scsi_device_set_state);
2352
2353
2354
2355
2356
2357
2358
2359
2360static void scsi_evt_emit(struct scsi_device *sdev, struct scsi_event *evt)
2361{
2362 int idx = 0;
2363 char *envp[3];
2364
2365 switch (evt->evt_type) {
2366 case SDEV_EVT_MEDIA_CHANGE:
2367 envp[idx++] = "SDEV_MEDIA_CHANGE=1";
2368 break;
2369 case SDEV_EVT_INQUIRY_CHANGE_REPORTED:
2370 scsi_rescan_device(&sdev->sdev_gendev);
2371 envp[idx++] = "SDEV_UA=INQUIRY_DATA_HAS_CHANGED";
2372 break;
2373 case SDEV_EVT_CAPACITY_CHANGE_REPORTED:
2374 envp[idx++] = "SDEV_UA=CAPACITY_DATA_HAS_CHANGED";
2375 break;
2376 case SDEV_EVT_SOFT_THRESHOLD_REACHED_REPORTED:
2377 envp[idx++] = "SDEV_UA=THIN_PROVISIONING_SOFT_THRESHOLD_REACHED";
2378 break;
2379 case SDEV_EVT_MODE_PARAMETER_CHANGE_REPORTED:
2380 envp[idx++] = "SDEV_UA=MODE_PARAMETERS_CHANGED";
2381 break;
2382 case SDEV_EVT_LUN_CHANGE_REPORTED:
2383 envp[idx++] = "SDEV_UA=REPORTED_LUNS_DATA_HAS_CHANGED";
2384 break;
2385 case SDEV_EVT_ALUA_STATE_CHANGE_REPORTED:
2386 envp[idx++] = "SDEV_UA=ASYMMETRIC_ACCESS_STATE_CHANGED";
2387 break;
2388 case SDEV_EVT_POWER_ON_RESET_OCCURRED:
2389 envp[idx++] = "SDEV_UA=POWER_ON_RESET_OCCURRED";
2390 break;
2391 default:
2392
2393 break;
2394 }
2395
2396 envp[idx++] = NULL;
2397
2398 kobject_uevent_env(&sdev->sdev_gendev.kobj, KOBJ_CHANGE, envp);
2399}
2400
2401
2402
2403
2404
2405
2406
2407
2408void scsi_evt_thread(struct work_struct *work)
2409{
2410 struct scsi_device *sdev;
2411 enum scsi_device_event evt_type;
2412 LIST_HEAD(event_list);
2413
2414 sdev = container_of(work, struct scsi_device, event_work);
2415
2416 for (evt_type = SDEV_EVT_FIRST; evt_type <= SDEV_EVT_LAST; evt_type++)
2417 if (test_and_clear_bit(evt_type, sdev->pending_events))
2418 sdev_evt_send_simple(sdev, evt_type, GFP_KERNEL);
2419
2420 while (1) {
2421 struct scsi_event *evt;
2422 struct list_head *this, *tmp;
2423 unsigned long flags;
2424
2425 spin_lock_irqsave(&sdev->list_lock, flags);
2426 list_splice_init(&sdev->event_list, &event_list);
2427 spin_unlock_irqrestore(&sdev->list_lock, flags);
2428
2429 if (list_empty(&event_list))
2430 break;
2431
2432 list_for_each_safe(this, tmp, &event_list) {
2433 evt = list_entry(this, struct scsi_event, node);
2434 list_del(&evt->node);
2435 scsi_evt_emit(sdev, evt);
2436 kfree(evt);
2437 }
2438 }
2439}
2440
2441
2442
2443
2444
2445
2446
2447
2448void sdev_evt_send(struct scsi_device *sdev, struct scsi_event *evt)
2449{
2450 unsigned long flags;
2451
2452#if 0
2453
2454
2455
2456 if (!test_bit(evt->evt_type, sdev->supported_events)) {
2457 kfree(evt);
2458 return;
2459 }
2460#endif
2461
2462 spin_lock_irqsave(&sdev->list_lock, flags);
2463 list_add_tail(&evt->node, &sdev->event_list);
2464 schedule_work(&sdev->event_work);
2465 spin_unlock_irqrestore(&sdev->list_lock, flags);
2466}
2467EXPORT_SYMBOL_GPL(sdev_evt_send);
2468
2469
2470
2471
2472
2473
2474
2475
2476struct scsi_event *sdev_evt_alloc(enum scsi_device_event evt_type,
2477 gfp_t gfpflags)
2478{
2479 struct scsi_event *evt = kzalloc(sizeof(struct scsi_event), gfpflags);
2480 if (!evt)
2481 return NULL;
2482
2483 evt->evt_type = evt_type;
2484 INIT_LIST_HEAD(&evt->node);
2485
2486
2487 switch (evt_type) {
2488 case SDEV_EVT_MEDIA_CHANGE:
2489 case SDEV_EVT_INQUIRY_CHANGE_REPORTED:
2490 case SDEV_EVT_CAPACITY_CHANGE_REPORTED:
2491 case SDEV_EVT_SOFT_THRESHOLD_REACHED_REPORTED:
2492 case SDEV_EVT_MODE_PARAMETER_CHANGE_REPORTED:
2493 case SDEV_EVT_LUN_CHANGE_REPORTED:
2494 case SDEV_EVT_ALUA_STATE_CHANGE_REPORTED:
2495 case SDEV_EVT_POWER_ON_RESET_OCCURRED:
2496 default:
2497
2498 break;
2499 }
2500
2501 return evt;
2502}
2503EXPORT_SYMBOL_GPL(sdev_evt_alloc);
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513void sdev_evt_send_simple(struct scsi_device *sdev,
2514 enum scsi_device_event evt_type, gfp_t gfpflags)
2515{
2516 struct scsi_event *evt = sdev_evt_alloc(evt_type, gfpflags);
2517 if (!evt) {
2518 sdev_printk(KERN_ERR, sdev, "event %d eaten due to OOM\n",
2519 evt_type);
2520 return;
2521 }
2522
2523 sdev_evt_send(sdev, evt);
2524}
2525EXPORT_SYMBOL_GPL(sdev_evt_send_simple);
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540int
2541scsi_device_quiesce(struct scsi_device *sdev)
2542{
2543 struct request_queue *q = sdev->request_queue;
2544 int err;
2545
2546
2547
2548
2549
2550
2551 WARN_ON_ONCE(sdev->quiesced_by && sdev->quiesced_by != current);
2552
2553 if (sdev->quiesced_by == current)
2554 return 0;
2555
2556 blk_set_pm_only(q);
2557
2558 blk_mq_freeze_queue(q);
2559
2560
2561
2562
2563
2564
2565 synchronize_rcu();
2566 blk_mq_unfreeze_queue(q);
2567
2568 mutex_lock(&sdev->state_mutex);
2569 err = scsi_device_set_state(sdev, SDEV_QUIESCE);
2570 if (err == 0)
2571 sdev->quiesced_by = current;
2572 else
2573 blk_clear_pm_only(q);
2574 mutex_unlock(&sdev->state_mutex);
2575
2576 return err;
2577}
2578EXPORT_SYMBOL(scsi_device_quiesce);
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589void scsi_device_resume(struct scsi_device *sdev)
2590{
2591
2592
2593
2594
2595 mutex_lock(&sdev->state_mutex);
2596 if (sdev->sdev_state == SDEV_QUIESCE)
2597 scsi_device_set_state(sdev, SDEV_RUNNING);
2598 if (sdev->quiesced_by) {
2599 sdev->quiesced_by = NULL;
2600 blk_clear_pm_only(sdev->request_queue);
2601 }
2602 mutex_unlock(&sdev->state_mutex);
2603}
2604EXPORT_SYMBOL(scsi_device_resume);
2605
2606static void
2607device_quiesce_fn(struct scsi_device *sdev, void *data)
2608{
2609 scsi_device_quiesce(sdev);
2610}
2611
2612void
2613scsi_target_quiesce(struct scsi_target *starget)
2614{
2615 starget_for_each_device(starget, NULL, device_quiesce_fn);
2616}
2617EXPORT_SYMBOL(scsi_target_quiesce);
2618
2619static void
2620device_resume_fn(struct scsi_device *sdev, void *data)
2621{
2622 scsi_device_resume(sdev);
2623}
2624
2625void
2626scsi_target_resume(struct scsi_target *starget)
2627{
2628 starget_for_each_device(starget, NULL, device_resume_fn);
2629}
2630EXPORT_SYMBOL(scsi_target_resume);
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646int scsi_internal_device_block_nowait(struct scsi_device *sdev)
2647{
2648 struct request_queue *q = sdev->request_queue;
2649 int err = 0;
2650
2651 err = scsi_device_set_state(sdev, SDEV_BLOCK);
2652 if (err) {
2653 err = scsi_device_set_state(sdev, SDEV_CREATED_BLOCK);
2654
2655 if (err)
2656 return err;
2657 }
2658
2659
2660
2661
2662
2663
2664 blk_mq_quiesce_queue_nowait(q);
2665 return 0;
2666}
2667EXPORT_SYMBOL_GPL(scsi_internal_device_block_nowait);
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684static int scsi_internal_device_block(struct scsi_device *sdev)
2685{
2686 struct request_queue *q = sdev->request_queue;
2687 int err;
2688
2689 mutex_lock(&sdev->state_mutex);
2690 err = scsi_internal_device_block_nowait(sdev);
2691 if (err == 0)
2692 blk_mq_quiesce_queue(q);
2693 mutex_unlock(&sdev->state_mutex);
2694
2695 return err;
2696}
2697
2698void scsi_start_queue(struct scsi_device *sdev)
2699{
2700 struct request_queue *q = sdev->request_queue;
2701
2702 blk_mq_unquiesce_queue(q);
2703}
2704
2705
2706
2707
2708
2709
2710
2711
2712
2713
2714
2715
2716
2717
2718
2719
2720int scsi_internal_device_unblock_nowait(struct scsi_device *sdev,
2721 enum scsi_device_state new_state)
2722{
2723 switch (new_state) {
2724 case SDEV_RUNNING:
2725 case SDEV_TRANSPORT_OFFLINE:
2726 break;
2727 default:
2728 return -EINVAL;
2729 }
2730
2731
2732
2733
2734
2735 switch (sdev->sdev_state) {
2736 case SDEV_BLOCK:
2737 case SDEV_TRANSPORT_OFFLINE:
2738 sdev->sdev_state = new_state;
2739 break;
2740 case SDEV_CREATED_BLOCK:
2741 if (new_state == SDEV_TRANSPORT_OFFLINE ||
2742 new_state == SDEV_OFFLINE)
2743 sdev->sdev_state = new_state;
2744 else
2745 sdev->sdev_state = SDEV_CREATED;
2746 break;
2747 case SDEV_CANCEL:
2748 case SDEV_OFFLINE:
2749 break;
2750 default:
2751 return -EINVAL;
2752 }
2753 scsi_start_queue(sdev);
2754
2755 return 0;
2756}
2757EXPORT_SYMBOL_GPL(scsi_internal_device_unblock_nowait);
2758
2759
2760
2761
2762
2763
2764
2765
2766
2767
2768
2769
2770
2771
2772
2773static int scsi_internal_device_unblock(struct scsi_device *sdev,
2774 enum scsi_device_state new_state)
2775{
2776 int ret;
2777
2778 mutex_lock(&sdev->state_mutex);
2779 ret = scsi_internal_device_unblock_nowait(sdev, new_state);
2780 mutex_unlock(&sdev->state_mutex);
2781
2782 return ret;
2783}
2784
2785static void
2786device_block(struct scsi_device *sdev, void *data)
2787{
2788 int ret;
2789
2790 ret = scsi_internal_device_block(sdev);
2791
2792 WARN_ONCE(ret, "scsi_internal_device_block(%s) failed: ret = %d\n",
2793 dev_name(&sdev->sdev_gendev), ret);
2794}
2795
2796static int
2797target_block(struct device *dev, void *data)
2798{
2799 if (scsi_is_target_device(dev))
2800 starget_for_each_device(to_scsi_target(dev), NULL,
2801 device_block);
2802 return 0;
2803}
2804
2805void
2806scsi_target_block(struct device *dev)
2807{
2808 if (scsi_is_target_device(dev))
2809 starget_for_each_device(to_scsi_target(dev), NULL,
2810 device_block);
2811 else
2812 device_for_each_child(dev, NULL, target_block);
2813}
2814EXPORT_SYMBOL_GPL(scsi_target_block);
2815
2816static void
2817device_unblock(struct scsi_device *sdev, void *data)
2818{
2819 scsi_internal_device_unblock(sdev, *(enum scsi_device_state *)data);
2820}
2821
2822static int
2823target_unblock(struct device *dev, void *data)
2824{
2825 if (scsi_is_target_device(dev))
2826 starget_for_each_device(to_scsi_target(dev), data,
2827 device_unblock);
2828 return 0;
2829}
2830
2831void
2832scsi_target_unblock(struct device *dev, enum scsi_device_state new_state)
2833{
2834 if (scsi_is_target_device(dev))
2835 starget_for_each_device(to_scsi_target(dev), &new_state,
2836 device_unblock);
2837 else
2838 device_for_each_child(dev, &new_state, target_unblock);
2839}
2840EXPORT_SYMBOL_GPL(scsi_target_unblock);
2841
2842int
2843scsi_host_block(struct Scsi_Host *shost)
2844{
2845 struct scsi_device *sdev;
2846 int ret = 0;
2847
2848
2849
2850
2851
2852 shost_for_each_device(sdev, shost) {
2853 mutex_lock(&sdev->state_mutex);
2854 ret = scsi_internal_device_block_nowait(sdev);
2855 mutex_unlock(&sdev->state_mutex);
2856 if (ret) {
2857 scsi_device_put(sdev);
2858 break;
2859 }
2860 }
2861
2862
2863
2864
2865
2866 WARN_ON_ONCE(shost->tag_set.flags & BLK_MQ_F_BLOCKING);
2867
2868 if (!ret)
2869 synchronize_rcu();
2870
2871 return ret;
2872}
2873EXPORT_SYMBOL_GPL(scsi_host_block);
2874
2875int
2876scsi_host_unblock(struct Scsi_Host *shost, int new_state)
2877{
2878 struct scsi_device *sdev;
2879 int ret = 0;
2880
2881 shost_for_each_device(sdev, shost) {
2882 ret = scsi_internal_device_unblock(sdev, new_state);
2883 if (ret) {
2884 scsi_device_put(sdev);
2885 break;
2886 }
2887 }
2888 return ret;
2889}
2890EXPORT_SYMBOL_GPL(scsi_host_unblock);
2891
2892
2893
2894
2895
2896
2897
2898
2899
2900
2901void *scsi_kmap_atomic_sg(struct scatterlist *sgl, int sg_count,
2902 size_t *offset, size_t *len)
2903{
2904 int i;
2905 size_t sg_len = 0, len_complete = 0;
2906 struct scatterlist *sg;
2907 struct page *page;
2908
2909 WARN_ON(!irqs_disabled());
2910
2911 for_each_sg(sgl, sg, sg_count, i) {
2912 len_complete = sg_len;
2913 sg_len += sg->length;
2914 if (sg_len > *offset)
2915 break;
2916 }
2917
2918 if (unlikely(i == sg_count)) {
2919 printk(KERN_ERR "%s: Bytes in sg: %zu, requested offset %zu, "
2920 "elements %d\n",
2921 __func__, sg_len, *offset, sg_count);
2922 WARN_ON(1);
2923 return NULL;
2924 }
2925
2926
2927 *offset = *offset - len_complete + sg->offset;
2928
2929
2930 page = nth_page(sg_page(sg), (*offset >> PAGE_SHIFT));
2931 *offset &= ~PAGE_MASK;
2932
2933
2934 sg_len = PAGE_SIZE - *offset;
2935 if (*len > sg_len)
2936 *len = sg_len;
2937
2938 return kmap_atomic(page);
2939}
2940EXPORT_SYMBOL(scsi_kmap_atomic_sg);
2941
2942
2943
2944
2945
2946void scsi_kunmap_atomic_sg(void *virt)
2947{
2948 kunmap_atomic(virt);
2949}
2950EXPORT_SYMBOL(scsi_kunmap_atomic_sg);
2951
2952void sdev_disable_disk_events(struct scsi_device *sdev)
2953{
2954 atomic_inc(&sdev->disk_events_disable_depth);
2955}
2956EXPORT_SYMBOL(sdev_disable_disk_events);
2957
2958void sdev_enable_disk_events(struct scsi_device *sdev)
2959{
2960 if (WARN_ON_ONCE(atomic_read(&sdev->disk_events_disable_depth) <= 0))
2961 return;
2962 atomic_dec(&sdev->disk_events_disable_depth);
2963}
2964EXPORT_SYMBOL(sdev_enable_disk_events);
2965
2966static unsigned char designator_prio(const unsigned char *d)
2967{
2968 if (d[1] & 0x30)
2969
2970 return 0;
2971
2972 if (d[3] == 0)
2973
2974 return 0;
2975
2976
2977
2978
2979
2980
2981
2982
2983
2984
2985
2986
2987
2988
2989
2990
2991 switch (d[1] & 0xf) {
2992 case 8:
2993
2994 return 9;
2995 case 3:
2996 switch (d[4] >> 4) {
2997 case 6:
2998
2999 return 8;
3000 case 5:
3001
3002 return 5;
3003 case 4:
3004
3005 return 4;
3006 case 3:
3007
3008 return 1;
3009 default:
3010 break;
3011 }
3012 break;
3013 case 2:
3014 switch (d[3]) {
3015 case 16:
3016
3017 return 7;
3018 case 12:
3019
3020 return 6;
3021 case 8:
3022
3023 return 3;
3024 default:
3025 break;
3026 }
3027 break;
3028 case 1:
3029
3030 return 1;
3031 default:
3032 break;
3033 }
3034
3035 return 0;
3036}
3037
3038
3039
3040
3041
3042
3043
3044
3045
3046
3047
3048
3049
3050
3051
3052int scsi_vpd_lun_id(struct scsi_device *sdev, char *id, size_t id_len)
3053{
3054 u8 cur_id_prio = 0;
3055 u8 cur_id_size = 0;
3056 const unsigned char *d, *cur_id_str;
3057 const struct scsi_vpd *vpd_pg83;
3058 int id_size = -EINVAL;
3059
3060 rcu_read_lock();
3061 vpd_pg83 = rcu_dereference(sdev->vpd_pg83);
3062 if (!vpd_pg83) {
3063 rcu_read_unlock();
3064 return -ENXIO;
3065 }
3066
3067
3068 if (id_len < 21) {
3069 rcu_read_unlock();
3070 return -EINVAL;
3071 }
3072
3073 memset(id, 0, id_len);
3074 for (d = vpd_pg83->data + 4;
3075 d < vpd_pg83->data + vpd_pg83->len;
3076 d += d[3] + 4) {
3077 u8 prio = designator_prio(d);
3078
3079 if (prio == 0 || cur_id_prio > prio)
3080 continue;
3081
3082 switch (d[1] & 0xf) {
3083 case 0x1:
3084
3085 if (cur_id_size > d[3])
3086 break;
3087 cur_id_prio = prio;
3088 cur_id_size = d[3];
3089 if (cur_id_size + 4 > id_len)
3090 cur_id_size = id_len - 4;
3091 cur_id_str = d + 4;
3092 id_size = snprintf(id, id_len, "t10.%*pE",
3093 cur_id_size, cur_id_str);
3094 break;
3095 case 0x2:
3096
3097 cur_id_prio = prio;
3098 cur_id_size = d[3];
3099 cur_id_str = d + 4;
3100 switch (cur_id_size) {
3101 case 8:
3102 id_size = snprintf(id, id_len,
3103 "eui.%8phN",
3104 cur_id_str);
3105 break;
3106 case 12:
3107 id_size = snprintf(id, id_len,
3108 "eui.%12phN",
3109 cur_id_str);
3110 break;
3111 case 16:
3112 id_size = snprintf(id, id_len,
3113 "eui.%16phN",
3114 cur_id_str);
3115 break;
3116 default:
3117 break;
3118 }
3119 break;
3120 case 0x3:
3121
3122 cur_id_prio = prio;
3123 cur_id_size = d[3];
3124 cur_id_str = d + 4;
3125 switch (cur_id_size) {
3126 case 8:
3127 id_size = snprintf(id, id_len,
3128 "naa.%8phN",
3129 cur_id_str);
3130 break;
3131 case 16:
3132 id_size = snprintf(id, id_len,
3133 "naa.%16phN",
3134 cur_id_str);
3135 break;
3136 default:
3137 break;
3138 }
3139 break;
3140 case 0x8:
3141
3142 if (cur_id_size > d[3])
3143 break;
3144
3145 if (d[3] > id_len) {
3146 prio = 2;
3147 if (cur_id_prio > prio)
3148 break;
3149 }
3150 cur_id_prio = prio;
3151 cur_id_size = id_size = d[3];
3152 cur_id_str = d + 4;
3153 if (cur_id_size >= id_len)
3154 cur_id_size = id_len - 1;
3155 memcpy(id, cur_id_str, cur_id_size);
3156 break;
3157 default:
3158 break;
3159 }
3160 }
3161 rcu_read_unlock();
3162
3163 return id_size;
3164}
3165EXPORT_SYMBOL(scsi_vpd_lun_id);
3166
3167
3168
3169
3170
3171
3172
3173
3174
3175
3176int scsi_vpd_tpg_id(struct scsi_device *sdev, int *rel_id)
3177{
3178 const unsigned char *d;
3179 const struct scsi_vpd *vpd_pg83;
3180 int group_id = -EAGAIN, rel_port = -1;
3181
3182 rcu_read_lock();
3183 vpd_pg83 = rcu_dereference(sdev->vpd_pg83);
3184 if (!vpd_pg83) {
3185 rcu_read_unlock();
3186 return -ENXIO;
3187 }
3188
3189 d = vpd_pg83->data + 4;
3190 while (d < vpd_pg83->data + vpd_pg83->len) {
3191 switch (d[1] & 0xf) {
3192 case 0x4:
3193
3194 rel_port = get_unaligned_be16(&d[6]);
3195 break;
3196 case 0x5:
3197
3198 group_id = get_unaligned_be16(&d[6]);
3199 break;
3200 default:
3201 break;
3202 }
3203 d += d[3] + 4;
3204 }
3205 rcu_read_unlock();
3206
3207 if (group_id >= 0 && rel_id && rel_port != -1)
3208 *rel_id = rel_port;
3209
3210 return group_id;
3211}
3212EXPORT_SYMBOL(scsi_vpd_tpg_id);
3213
3214
3215
3216
3217
3218
3219
3220
3221
3222
3223
3224void scsi_build_sense(struct scsi_cmnd *scmd, int desc, u8 key, u8 asc, u8 ascq)
3225{
3226 scsi_build_sense_buffer(desc, scmd->sense_buffer, key, asc, ascq);
3227 scmd->result = SAM_STAT_CHECK_CONDITION;
3228}
3229EXPORT_SYMBOL_GPL(scsi_build_sense);
3230