1
2
3
4
5
6
7
8
9
10
11
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 if (cmd->request->rq_flags & RQF_DONTPREP) {
123 cmd->request->rq_flags &= ~RQF_DONTPREP;
124 scsi_mq_uninit_cmd(cmd);
125 } else {
126 WARN_ON_ONCE(true);
127 }
128 blk_mq_requeue_request(cmd->request, true);
129}
130
131
132
133
134
135
136
137
138
139
140
141
142
143static void __scsi_queue_insert(struct scsi_cmnd *cmd, int reason, bool unbusy)
144{
145 struct scsi_device *device = cmd->device;
146
147 SCSI_LOG_MLQUEUE(1, scmd_printk(KERN_INFO, cmd,
148 "Inserting command %p into mlqueue\n", cmd));
149
150 scsi_set_blocked(cmd, reason);
151
152
153
154
155
156 if (unbusy)
157 scsi_device_unbusy(device, cmd);
158
159
160
161
162
163
164
165 cmd->result = 0;
166
167 blk_mq_requeue_request(cmd->request, true);
168}
169
170
171
172
173
174
175
176
177
178
179
180
181
182void scsi_queue_insert(struct scsi_cmnd *cmd, int reason)
183{
184 __scsi_queue_insert(cmd, reason, true);
185}
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206int __scsi_execute(struct scsi_device *sdev, const unsigned char *cmd,
207 int data_direction, void *buffer, unsigned bufflen,
208 unsigned char *sense, struct scsi_sense_hdr *sshdr,
209 int timeout, int retries, u64 flags, req_flags_t rq_flags,
210 int *resid)
211{
212 struct request *req;
213 struct scsi_request *rq;
214 int ret;
215
216 req = blk_get_request(sdev->request_queue,
217 data_direction == DMA_TO_DEVICE ?
218 REQ_OP_DRV_OUT : REQ_OP_DRV_IN,
219 rq_flags & RQF_PM ? BLK_MQ_REQ_PM : 0);
220 if (IS_ERR(req))
221 return PTR_ERR(req);
222
223 rq = scsi_req(req);
224
225 if (bufflen) {
226 ret = blk_rq_map_kern(sdev->request_queue, req,
227 buffer, bufflen, GFP_NOIO);
228 if (ret)
229 goto out;
230 }
231 rq->cmd_len = COMMAND_SIZE(cmd[0]);
232 memcpy(rq->cmd, cmd, rq->cmd_len);
233 rq->retries = retries;
234 req->timeout = timeout;
235 req->cmd_flags |= flags;
236 req->rq_flags |= rq_flags | RQF_QUIET;
237
238
239
240
241 blk_execute_rq(NULL, req, 1);
242
243
244
245
246
247
248
249 if (unlikely(rq->resid_len > 0 && rq->resid_len <= bufflen))
250 memset(buffer + (bufflen - rq->resid_len), 0, rq->resid_len);
251
252 if (resid)
253 *resid = rq->resid_len;
254 if (sense && rq->sense_len)
255 memcpy(sense, rq->sense, SCSI_SENSE_BUFFERSIZE);
256 if (sshdr)
257 scsi_normalize_sense(rq->sense, rq->sense_len, sshdr);
258 ret = rq->result;
259 out:
260 blk_put_request(req);
261
262 return ret;
263}
264EXPORT_SYMBOL(__scsi_execute);
265
266
267
268
269
270
271
272
273
274
275static void scsi_dec_host_busy(struct Scsi_Host *shost, struct scsi_cmnd *cmd)
276{
277 unsigned long flags;
278
279 rcu_read_lock();
280 __clear_bit(SCMD_STATE_INFLIGHT, &cmd->state);
281 if (unlikely(scsi_host_in_recovery(shost))) {
282 spin_lock_irqsave(shost->host_lock, flags);
283 if (shost->host_failed || shost->host_eh_scheduled)
284 scsi_eh_wakeup(shost);
285 spin_unlock_irqrestore(shost->host_lock, flags);
286 }
287 rcu_read_unlock();
288}
289
290void scsi_device_unbusy(struct scsi_device *sdev, struct scsi_cmnd *cmd)
291{
292 struct Scsi_Host *shost = sdev->host;
293 struct scsi_target *starget = scsi_target(sdev);
294
295 scsi_dec_host_busy(shost, cmd);
296
297 if (starget->can_queue > 0)
298 atomic_dec(&starget->target_busy);
299
300 sbitmap_put(&sdev->budget_map, cmd->budget_token);
301 cmd->budget_token = -1;
302}
303
304static void scsi_kick_queue(struct request_queue *q)
305{
306 blk_mq_run_hw_queues(q, false);
307}
308
309
310
311
312
313
314
315
316static void scsi_single_lun_run(struct scsi_device *current_sdev)
317{
318 struct Scsi_Host *shost = current_sdev->host;
319 struct scsi_device *sdev, *tmp;
320 struct scsi_target *starget = scsi_target(current_sdev);
321 unsigned long flags;
322
323 spin_lock_irqsave(shost->host_lock, flags);
324 starget->starget_sdev_user = NULL;
325 spin_unlock_irqrestore(shost->host_lock, flags);
326
327
328
329
330
331
332
333 scsi_kick_queue(current_sdev->request_queue);
334
335 spin_lock_irqsave(shost->host_lock, flags);
336 if (starget->starget_sdev_user)
337 goto out;
338 list_for_each_entry_safe(sdev, tmp, &starget->devices,
339 same_target_siblings) {
340 if (sdev == current_sdev)
341 continue;
342 if (scsi_device_get(sdev))
343 continue;
344
345 spin_unlock_irqrestore(shost->host_lock, flags);
346 scsi_kick_queue(sdev->request_queue);
347 spin_lock_irqsave(shost->host_lock, flags);
348
349 scsi_device_put(sdev);
350 }
351 out:
352 spin_unlock_irqrestore(shost->host_lock, flags);
353}
354
355static inline bool scsi_device_is_busy(struct scsi_device *sdev)
356{
357 if (scsi_device_busy(sdev) >= sdev->queue_depth)
358 return true;
359 if (atomic_read(&sdev->device_blocked) > 0)
360 return true;
361 return false;
362}
363
364static inline bool scsi_target_is_busy(struct scsi_target *starget)
365{
366 if (starget->can_queue > 0) {
367 if (atomic_read(&starget->target_busy) >= starget->can_queue)
368 return true;
369 if (atomic_read(&starget->target_blocked) > 0)
370 return true;
371 }
372 return false;
373}
374
375static inline bool scsi_host_is_busy(struct Scsi_Host *shost)
376{
377 if (atomic_read(&shost->host_blocked) > 0)
378 return true;
379 if (shost->host_self_blocked)
380 return true;
381 return false;
382}
383
384static void scsi_starved_list_run(struct Scsi_Host *shost)
385{
386 LIST_HEAD(starved_list);
387 struct scsi_device *sdev;
388 unsigned long flags;
389
390 spin_lock_irqsave(shost->host_lock, flags);
391 list_splice_init(&shost->starved_list, &starved_list);
392
393 while (!list_empty(&starved_list)) {
394 struct request_queue *slq;
395
396
397
398
399
400
401
402
403
404
405
406 if (scsi_host_is_busy(shost))
407 break;
408
409 sdev = list_entry(starved_list.next,
410 struct scsi_device, starved_entry);
411 list_del_init(&sdev->starved_entry);
412 if (scsi_target_is_busy(scsi_target(sdev))) {
413 list_move_tail(&sdev->starved_entry,
414 &shost->starved_list);
415 continue;
416 }
417
418
419
420
421
422
423
424
425
426
427
428 slq = sdev->request_queue;
429 if (!blk_get_queue(slq))
430 continue;
431 spin_unlock_irqrestore(shost->host_lock, flags);
432
433 scsi_kick_queue(slq);
434 blk_put_queue(slq);
435
436 spin_lock_irqsave(shost->host_lock, flags);
437 }
438
439 list_splice(&starved_list, &shost->starved_list);
440 spin_unlock_irqrestore(shost->host_lock, flags);
441}
442
443
444
445
446
447
448
449static void scsi_run_queue(struct request_queue *q)
450{
451 struct scsi_device *sdev = q->queuedata;
452
453 if (scsi_target(sdev)->single_lun)
454 scsi_single_lun_run(sdev);
455 if (!list_empty(&sdev->host->starved_list))
456 scsi_starved_list_run(sdev->host);
457
458 blk_mq_run_hw_queues(q, false);
459}
460
461void scsi_requeue_run_queue(struct work_struct *work)
462{
463 struct scsi_device *sdev;
464 struct request_queue *q;
465
466 sdev = container_of(work, struct scsi_device, requeue_work);
467 q = sdev->request_queue;
468 scsi_run_queue(q);
469}
470
471void scsi_run_host_queues(struct Scsi_Host *shost)
472{
473 struct scsi_device *sdev;
474
475 shost_for_each_device(sdev, shost)
476 scsi_run_queue(sdev->request_queue);
477}
478
479static void scsi_uninit_cmd(struct scsi_cmnd *cmd)
480{
481 if (!blk_rq_is_passthrough(cmd->request)) {
482 struct scsi_driver *drv = scsi_cmd_to_driver(cmd);
483
484 if (drv->uninit_command)
485 drv->uninit_command(cmd);
486 }
487}
488
489void scsi_free_sgtables(struct scsi_cmnd *cmd)
490{
491 if (cmd->sdb.table.nents)
492 sg_free_table_chained(&cmd->sdb.table,
493 SCSI_INLINE_SG_CNT);
494 if (scsi_prot_sg_count(cmd))
495 sg_free_table_chained(&cmd->prot_sdb->table,
496 SCSI_INLINE_PROT_SG_CNT);
497}
498EXPORT_SYMBOL_GPL(scsi_free_sgtables);
499
500static void scsi_mq_uninit_cmd(struct scsi_cmnd *cmd)
501{
502 scsi_free_sgtables(cmd);
503 scsi_uninit_cmd(cmd);
504}
505
506static void scsi_run_queue_async(struct scsi_device *sdev)
507{
508 if (scsi_target(sdev)->single_lun ||
509 !list_empty(&sdev->host->starved_list)) {
510 kblockd_schedule_work(&sdev->requeue_work);
511 } else {
512
513
514
515
516
517 int old = atomic_read(&sdev->restarts);
518
519
520
521
522
523
524
525
526
527 if (old && atomic_cmpxchg(&sdev->restarts, old, 0) == old)
528 blk_mq_run_hw_queues(sdev->request_queue, true);
529 }
530}
531
532
533static bool scsi_end_request(struct request *req, blk_status_t error,
534 unsigned int bytes)
535{
536 struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req);
537 struct scsi_device *sdev = cmd->device;
538 struct request_queue *q = sdev->request_queue;
539
540 if (blk_update_request(req, error, bytes))
541 return true;
542
543 if (blk_queue_add_random(q))
544 add_disk_randomness(req->rq_disk);
545
546 if (!blk_rq_is_passthrough(req)) {
547 WARN_ON_ONCE(!(cmd->flags & SCMD_INITIALIZED));
548 cmd->flags &= ~SCMD_INITIALIZED;
549 }
550
551
552
553
554
555
556
557 destroy_rcu_head(&cmd->rcu);
558
559
560
561
562
563
564
565
566 scsi_mq_uninit_cmd(cmd);
567
568
569
570
571
572 percpu_ref_get(&q->q_usage_counter);
573
574 __blk_mq_end_request(req, error);
575
576 scsi_run_queue_async(sdev);
577
578 percpu_ref_put(&q->q_usage_counter);
579 return false;
580}
581
582
583
584
585
586
587
588
589
590static blk_status_t scsi_result_to_blk_status(struct scsi_cmnd *cmd, int result)
591{
592 switch (host_byte(result)) {
593 case DID_OK:
594 if (scsi_status_is_good(result))
595 return BLK_STS_OK;
596 return BLK_STS_IOERR;
597 case DID_TRANSPORT_FAILFAST:
598 case DID_TRANSPORT_MARGINAL:
599 return BLK_STS_TRANSPORT;
600 case DID_TARGET_FAILURE:
601 set_host_byte(cmd, DID_OK);
602 return BLK_STS_TARGET;
603 case DID_NEXUS_FAILURE:
604 set_host_byte(cmd, DID_OK);
605 return BLK_STS_NEXUS;
606 case DID_ALLOC_FAILURE:
607 set_host_byte(cmd, DID_OK);
608 return BLK_STS_NOSPC;
609 case DID_MEDIUM_ERROR:
610 set_host_byte(cmd, DID_OK);
611 return BLK_STS_MEDIUM;
612 default:
613 return BLK_STS_IOERR;
614 }
615}
616
617
618static void scsi_io_completion_reprep(struct scsi_cmnd *cmd,
619 struct request_queue *q)
620{
621
622 scsi_mq_requeue_cmd(cmd);
623}
624
625static bool scsi_cmd_runtime_exceeced(struct scsi_cmnd *cmd)
626{
627 struct request *req = cmd->request;
628 unsigned long wait_for;
629
630 if (cmd->allowed == SCSI_CMD_RETRIES_NO_LIMIT)
631 return false;
632
633 wait_for = (cmd->allowed + 1) * req->timeout;
634 if (time_before(cmd->jiffies_at_alloc + wait_for, jiffies)) {
635 scmd_printk(KERN_ERR, cmd, "timing out command, waited %lus\n",
636 wait_for/HZ);
637 return true;
638 }
639 return false;
640}
641
642
643static void scsi_io_completion_action(struct scsi_cmnd *cmd, int result)
644{
645 struct request_queue *q = cmd->device->request_queue;
646 struct request *req = cmd->request;
647 int level = 0;
648 enum {ACTION_FAIL, ACTION_REPREP, ACTION_RETRY,
649 ACTION_DELAYED_RETRY} action;
650 struct scsi_sense_hdr sshdr;
651 bool sense_valid;
652 bool sense_current = true;
653 blk_status_t blk_stat;
654
655 sense_valid = scsi_command_normalize_sense(cmd, &sshdr);
656 if (sense_valid)
657 sense_current = !scsi_sense_is_deferred(&sshdr);
658
659 blk_stat = scsi_result_to_blk_status(cmd, result);
660
661 if (host_byte(result) == DID_RESET) {
662
663
664
665
666 action = ACTION_RETRY;
667 } else if (sense_valid && sense_current) {
668 switch (sshdr.sense_key) {
669 case UNIT_ATTENTION:
670 if (cmd->device->removable) {
671
672
673
674 cmd->device->changed = 1;
675 action = ACTION_FAIL;
676 } else {
677
678
679
680
681
682 action = ACTION_RETRY;
683 }
684 break;
685 case ILLEGAL_REQUEST:
686
687
688
689
690
691
692
693
694 if ((cmd->device->use_10_for_rw &&
695 sshdr.asc == 0x20 && sshdr.ascq == 0x00) &&
696 (cmd->cmnd[0] == READ_10 ||
697 cmd->cmnd[0] == WRITE_10)) {
698
699 cmd->device->use_10_for_rw = 0;
700 action = ACTION_REPREP;
701 } else if (sshdr.asc == 0x10) {
702 action = ACTION_FAIL;
703 blk_stat = BLK_STS_PROTECTION;
704
705 } else if (sshdr.asc == 0x20 || sshdr.asc == 0x24) {
706 action = ACTION_FAIL;
707 blk_stat = BLK_STS_TARGET;
708 } else
709 action = ACTION_FAIL;
710 break;
711 case ABORTED_COMMAND:
712 action = ACTION_FAIL;
713 if (sshdr.asc == 0x10)
714 blk_stat = BLK_STS_PROTECTION;
715 break;
716 case NOT_READY:
717
718
719
720 if (sshdr.asc == 0x04) {
721 switch (sshdr.ascq) {
722 case 0x01:
723 case 0x04:
724 case 0x05:
725 case 0x06:
726 case 0x07:
727 case 0x08:
728 case 0x09:
729 case 0x11:
730 case 0x14:
731 case 0x1a:
732 case 0x1b:
733 case 0x1d:
734 case 0x24:
735 action = ACTION_DELAYED_RETRY;
736 break;
737 case 0x0a:
738 blk_stat = BLK_STS_AGAIN;
739 fallthrough;
740 default:
741 action = ACTION_FAIL;
742 break;
743 }
744 } else
745 action = ACTION_FAIL;
746 break;
747 case VOLUME_OVERFLOW:
748
749 action = ACTION_FAIL;
750 break;
751 case DATA_PROTECT:
752 action = ACTION_FAIL;
753 if ((sshdr.asc == 0x0C && sshdr.ascq == 0x12) ||
754 (sshdr.asc == 0x55 &&
755 (sshdr.ascq == 0x0E || sshdr.ascq == 0x0F))) {
756
757 blk_stat = BLK_STS_ZONE_OPEN_RESOURCE;
758 }
759 break;
760 default:
761 action = ACTION_FAIL;
762 break;
763 }
764 } else
765 action = ACTION_FAIL;
766
767 if (action != ACTION_FAIL && scsi_cmd_runtime_exceeced(cmd))
768 action = ACTION_FAIL;
769
770 switch (action) {
771 case ACTION_FAIL:
772
773 if (!(req->rq_flags & RQF_QUIET)) {
774 static DEFINE_RATELIMIT_STATE(_rs,
775 DEFAULT_RATELIMIT_INTERVAL,
776 DEFAULT_RATELIMIT_BURST);
777
778 if (unlikely(scsi_logging_level))
779 level =
780 SCSI_LOG_LEVEL(SCSI_LOG_MLCOMPLETE_SHIFT,
781 SCSI_LOG_MLCOMPLETE_BITS);
782
783
784
785
786
787 if (!level && __ratelimit(&_rs)) {
788 scsi_print_result(cmd, NULL, FAILED);
789 if (sense_valid)
790 scsi_print_sense(cmd);
791 scsi_print_command(cmd);
792 }
793 }
794 if (!scsi_end_request(req, blk_stat, blk_rq_err_bytes(req)))
795 return;
796 fallthrough;
797 case ACTION_REPREP:
798 scsi_io_completion_reprep(cmd, q);
799 break;
800 case ACTION_RETRY:
801
802 __scsi_queue_insert(cmd, SCSI_MLQUEUE_EH_RETRY, false);
803 break;
804 case ACTION_DELAYED_RETRY:
805
806 __scsi_queue_insert(cmd, SCSI_MLQUEUE_DEVICE_BUSY, false);
807 break;
808 }
809}
810
811
812
813
814
815
816static int scsi_io_completion_nz_result(struct scsi_cmnd *cmd, int result,
817 blk_status_t *blk_statp)
818{
819 bool sense_valid;
820 bool sense_current = true;
821 struct request *req = cmd->request;
822 struct scsi_sense_hdr sshdr;
823
824 sense_valid = scsi_command_normalize_sense(cmd, &sshdr);
825 if (sense_valid)
826 sense_current = !scsi_sense_is_deferred(&sshdr);
827
828 if (blk_rq_is_passthrough(req)) {
829 if (sense_valid) {
830
831
832
833 scsi_req(req)->sense_len =
834 min(8 + cmd->sense_buffer[7],
835 SCSI_SENSE_BUFFERSIZE);
836 }
837 if (sense_current)
838 *blk_statp = scsi_result_to_blk_status(cmd, result);
839 } else if (blk_rq_bytes(req) == 0 && sense_current) {
840
841
842
843
844
845 *blk_statp = scsi_result_to_blk_status(cmd, result);
846 }
847
848
849
850
851
852
853 if (sense_valid && (sshdr.sense_key == RECOVERED_ERROR)) {
854 bool do_print = true;
855
856
857
858
859
860 if ((sshdr.asc == 0x0) && (sshdr.ascq == 0x1d))
861 do_print = false;
862 else if (req->rq_flags & RQF_QUIET)
863 do_print = false;
864 if (do_print)
865 scsi_print_sense(cmd);
866 result = 0;
867
868 *blk_statp = BLK_STS_OK;
869 }
870
871
872
873
874
875
876
877 if ((result & 0xff) && scsi_status_is_good(result)) {
878 result = 0;
879 *blk_statp = BLK_STS_OK;
880 }
881 return result;
882}
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes)
907{
908 int result = cmd->result;
909 struct request_queue *q = cmd->device->request_queue;
910 struct request *req = cmd->request;
911 blk_status_t blk_stat = BLK_STS_OK;
912
913 if (unlikely(result))
914 result = scsi_io_completion_nz_result(cmd, result, &blk_stat);
915
916 if (unlikely(blk_rq_is_passthrough(req))) {
917
918
919
920 scsi_req(req)->result = cmd->result;
921 }
922
923
924
925
926
927 SCSI_LOG_HLCOMPLETE(1, scmd_printk(KERN_INFO, cmd,
928 "%u sectors total, %d bytes done.\n",
929 blk_rq_sectors(req), good_bytes));
930
931
932
933
934
935 if (likely(blk_rq_bytes(req) > 0 || blk_stat == BLK_STS_OK)) {
936 if (likely(!scsi_end_request(req, blk_stat, good_bytes)))
937 return;
938 }
939
940
941 if (unlikely(blk_stat && scsi_noretry_cmd(cmd))) {
942 if (scsi_end_request(req, blk_stat, blk_rq_bytes(req)))
943 WARN_ONCE(true,
944 "Bytes remaining after failed, no-retry command");
945 return;
946 }
947
948
949
950
951
952 if (likely(result == 0))
953 scsi_io_completion_reprep(cmd, q);
954 else
955 scsi_io_completion_action(cmd, result);
956}
957
958static inline bool scsi_cmd_needs_dma_drain(struct scsi_device *sdev,
959 struct request *rq)
960{
961 return sdev->dma_drain_len && blk_rq_is_passthrough(rq) &&
962 !op_is_write(req_op(rq)) &&
963 sdev->host->hostt->dma_need_drain(rq);
964}
965
966
967
968
969
970
971
972
973
974
975
976
977
978blk_status_t scsi_alloc_sgtables(struct scsi_cmnd *cmd)
979{
980 struct scsi_device *sdev = cmd->device;
981 struct request *rq = cmd->request;
982 unsigned short nr_segs = blk_rq_nr_phys_segments(rq);
983 struct scatterlist *last_sg = NULL;
984 blk_status_t ret;
985 bool need_drain = scsi_cmd_needs_dma_drain(sdev, rq);
986 int count;
987
988 if (WARN_ON_ONCE(!nr_segs))
989 return BLK_STS_IOERR;
990
991
992
993
994
995 if (need_drain)
996 nr_segs++;
997
998
999
1000
1001 if (unlikely(sg_alloc_table_chained(&cmd->sdb.table, nr_segs,
1002 cmd->sdb.table.sgl, SCSI_INLINE_SG_CNT)))
1003 return BLK_STS_RESOURCE;
1004
1005
1006
1007
1008
1009 count = __blk_rq_map_sg(rq->q, rq, cmd->sdb.table.sgl, &last_sg);
1010
1011 if (blk_rq_bytes(rq) & rq->q->dma_pad_mask) {
1012 unsigned int pad_len =
1013 (rq->q->dma_pad_mask & ~blk_rq_bytes(rq)) + 1;
1014
1015 last_sg->length += pad_len;
1016 cmd->extra_len += pad_len;
1017 }
1018
1019 if (need_drain) {
1020 sg_unmark_end(last_sg);
1021 last_sg = sg_next(last_sg);
1022 sg_set_buf(last_sg, sdev->dma_drain_buf, sdev->dma_drain_len);
1023 sg_mark_end(last_sg);
1024
1025 cmd->extra_len += sdev->dma_drain_len;
1026 count++;
1027 }
1028
1029 BUG_ON(count > cmd->sdb.table.nents);
1030 cmd->sdb.table.nents = count;
1031 cmd->sdb.length = blk_rq_payload_bytes(rq);
1032
1033 if (blk_integrity_rq(rq)) {
1034 struct scsi_data_buffer *prot_sdb = cmd->prot_sdb;
1035 int ivecs;
1036
1037 if (WARN_ON_ONCE(!prot_sdb)) {
1038
1039
1040
1041
1042
1043 ret = BLK_STS_IOERR;
1044 goto out_free_sgtables;
1045 }
1046
1047 ivecs = blk_rq_count_integrity_sg(rq->q, rq->bio);
1048
1049 if (sg_alloc_table_chained(&prot_sdb->table, ivecs,
1050 prot_sdb->table.sgl,
1051 SCSI_INLINE_PROT_SG_CNT)) {
1052 ret = BLK_STS_RESOURCE;
1053 goto out_free_sgtables;
1054 }
1055
1056 count = blk_rq_map_integrity_sg(rq->q, rq->bio,
1057 prot_sdb->table.sgl);
1058 BUG_ON(count > ivecs);
1059 BUG_ON(count > queue_max_integrity_segments(rq->q));
1060
1061 cmd->prot_sdb = prot_sdb;
1062 cmd->prot_sdb->table.nents = count;
1063 }
1064
1065 return BLK_STS_OK;
1066out_free_sgtables:
1067 scsi_free_sgtables(cmd);
1068 return ret;
1069}
1070EXPORT_SYMBOL(scsi_alloc_sgtables);
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083static void scsi_initialize_rq(struct request *rq)
1084{
1085 struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq);
1086
1087 scsi_req_init(&cmd->req);
1088 init_rcu_head(&cmd->rcu);
1089 cmd->jiffies_at_alloc = jiffies;
1090 cmd->retries = 0;
1091}
1092
1093
1094
1095
1096
1097static void scsi_cleanup_rq(struct request *rq)
1098{
1099 if (rq->rq_flags & RQF_DONTPREP) {
1100 scsi_mq_uninit_cmd(blk_mq_rq_to_pdu(rq));
1101 rq->rq_flags &= ~RQF_DONTPREP;
1102 }
1103}
1104
1105
1106void scsi_init_command(struct scsi_device *dev, struct scsi_cmnd *cmd)
1107{
1108 void *buf = cmd->sense_buffer;
1109 void *prot = cmd->prot_sdb;
1110 struct request *rq = blk_mq_rq_from_pdu(cmd);
1111 unsigned int flags = cmd->flags & SCMD_PRESERVED_FLAGS;
1112 unsigned long jiffies_at_alloc;
1113 int retries, to_clear;
1114 bool in_flight;
1115 int budget_token = cmd->budget_token;
1116
1117 if (!blk_rq_is_passthrough(rq) && !(flags & SCMD_INITIALIZED)) {
1118 flags |= SCMD_INITIALIZED;
1119 scsi_initialize_rq(rq);
1120 }
1121
1122 jiffies_at_alloc = cmd->jiffies_at_alloc;
1123 retries = cmd->retries;
1124 in_flight = test_bit(SCMD_STATE_INFLIGHT, &cmd->state);
1125
1126
1127
1128
1129
1130 to_clear = sizeof(*cmd) - sizeof(cmd->req);
1131 if (!dev->host->hostt->init_cmd_priv)
1132 to_clear += dev->host->hostt->cmd_size;
1133 memset((char *)cmd + sizeof(cmd->req), 0, to_clear);
1134
1135 cmd->device = dev;
1136 cmd->sense_buffer = buf;
1137 cmd->prot_sdb = prot;
1138 cmd->flags = flags;
1139 INIT_DELAYED_WORK(&cmd->abort_work, scmd_eh_abort_handler);
1140 cmd->jiffies_at_alloc = jiffies_at_alloc;
1141 cmd->retries = retries;
1142 if (in_flight)
1143 __set_bit(SCMD_STATE_INFLIGHT, &cmd->state);
1144 cmd->budget_token = budget_token;
1145
1146}
1147
1148static blk_status_t scsi_setup_scsi_cmnd(struct scsi_device *sdev,
1149 struct request *req)
1150{
1151 struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req);
1152
1153
1154
1155
1156
1157
1158
1159 if (req->bio) {
1160 blk_status_t ret = scsi_alloc_sgtables(cmd);
1161 if (unlikely(ret != BLK_STS_OK))
1162 return ret;
1163 } else {
1164 BUG_ON(blk_rq_bytes(req));
1165
1166 memset(&cmd->sdb, 0, sizeof(cmd->sdb));
1167 }
1168
1169 cmd->cmd_len = scsi_req(req)->cmd_len;
1170 if (cmd->cmd_len == 0)
1171 cmd->cmd_len = scsi_command_size(cmd->cmnd);
1172 cmd->cmnd = scsi_req(req)->cmd;
1173 cmd->transfersize = blk_rq_bytes(req);
1174 cmd->allowed = scsi_req(req)->retries;
1175 return BLK_STS_OK;
1176}
1177
1178static blk_status_t
1179scsi_device_state_check(struct scsi_device *sdev, struct request *req)
1180{
1181 switch (sdev->sdev_state) {
1182 case SDEV_CREATED:
1183 return BLK_STS_OK;
1184 case SDEV_OFFLINE:
1185 case SDEV_TRANSPORT_OFFLINE:
1186
1187
1188
1189
1190
1191 if (!sdev->offline_already) {
1192 sdev->offline_already = true;
1193 sdev_printk(KERN_ERR, sdev,
1194 "rejecting I/O to offline device\n");
1195 }
1196 return BLK_STS_IOERR;
1197 case SDEV_DEL:
1198
1199
1200
1201
1202 sdev_printk(KERN_ERR, sdev,
1203 "rejecting I/O to dead device\n");
1204 return BLK_STS_IOERR;
1205 case SDEV_BLOCK:
1206 case SDEV_CREATED_BLOCK:
1207 return BLK_STS_RESOURCE;
1208 case SDEV_QUIESCE:
1209
1210
1211
1212
1213 if (req && WARN_ON_ONCE(!(req->rq_flags & RQF_PM)))
1214 return BLK_STS_RESOURCE;
1215 return BLK_STS_OK;
1216 default:
1217
1218
1219
1220
1221 if (req && !(req->rq_flags & RQF_PM))
1222 return BLK_STS_IOERR;
1223 return BLK_STS_OK;
1224 }
1225}
1226
1227
1228
1229
1230
1231static inline int scsi_dev_queue_ready(struct request_queue *q,
1232 struct scsi_device *sdev)
1233{
1234 int token;
1235
1236 token = sbitmap_get(&sdev->budget_map);
1237 if (atomic_read(&sdev->device_blocked)) {
1238 if (token < 0)
1239 goto out;
1240
1241 if (scsi_device_busy(sdev) > 1)
1242 goto out_dec;
1243
1244
1245
1246
1247 if (atomic_dec_return(&sdev->device_blocked) > 0)
1248 goto out_dec;
1249 SCSI_LOG_MLQUEUE(3, sdev_printk(KERN_INFO, sdev,
1250 "unblocking device at zero depth\n"));
1251 }
1252
1253 return token;
1254out_dec:
1255 if (token >= 0)
1256 sbitmap_put(&sdev->budget_map, token);
1257out:
1258 return -1;
1259}
1260
1261
1262
1263
1264
1265static inline int scsi_target_queue_ready(struct Scsi_Host *shost,
1266 struct scsi_device *sdev)
1267{
1268 struct scsi_target *starget = scsi_target(sdev);
1269 unsigned int busy;
1270
1271 if (starget->single_lun) {
1272 spin_lock_irq(shost->host_lock);
1273 if (starget->starget_sdev_user &&
1274 starget->starget_sdev_user != sdev) {
1275 spin_unlock_irq(shost->host_lock);
1276 return 0;
1277 }
1278 starget->starget_sdev_user = sdev;
1279 spin_unlock_irq(shost->host_lock);
1280 }
1281
1282 if (starget->can_queue <= 0)
1283 return 1;
1284
1285 busy = atomic_inc_return(&starget->target_busy) - 1;
1286 if (atomic_read(&starget->target_blocked) > 0) {
1287 if (busy)
1288 goto starved;
1289
1290
1291
1292
1293 if (atomic_dec_return(&starget->target_blocked) > 0)
1294 goto out_dec;
1295
1296 SCSI_LOG_MLQUEUE(3, starget_printk(KERN_INFO, starget,
1297 "unblocking target at zero depth\n"));
1298 }
1299
1300 if (busy >= starget->can_queue)
1301 goto starved;
1302
1303 return 1;
1304
1305starved:
1306 spin_lock_irq(shost->host_lock);
1307 list_move_tail(&sdev->starved_entry, &shost->starved_list);
1308 spin_unlock_irq(shost->host_lock);
1309out_dec:
1310 if (starget->can_queue > 0)
1311 atomic_dec(&starget->target_busy);
1312 return 0;
1313}
1314
1315
1316
1317
1318
1319
1320static inline int scsi_host_queue_ready(struct request_queue *q,
1321 struct Scsi_Host *shost,
1322 struct scsi_device *sdev,
1323 struct scsi_cmnd *cmd)
1324{
1325 if (scsi_host_in_recovery(shost))
1326 return 0;
1327
1328 if (atomic_read(&shost->host_blocked) > 0) {
1329 if (scsi_host_busy(shost) > 0)
1330 goto starved;
1331
1332
1333
1334
1335 if (atomic_dec_return(&shost->host_blocked) > 0)
1336 goto out_dec;
1337
1338 SCSI_LOG_MLQUEUE(3,
1339 shost_printk(KERN_INFO, shost,
1340 "unblocking host at zero depth\n"));
1341 }
1342
1343 if (shost->host_self_blocked)
1344 goto starved;
1345
1346
1347 if (!list_empty(&sdev->starved_entry)) {
1348 spin_lock_irq(shost->host_lock);
1349 if (!list_empty(&sdev->starved_entry))
1350 list_del_init(&sdev->starved_entry);
1351 spin_unlock_irq(shost->host_lock);
1352 }
1353
1354 __set_bit(SCMD_STATE_INFLIGHT, &cmd->state);
1355
1356 return 1;
1357
1358starved:
1359 spin_lock_irq(shost->host_lock);
1360 if (list_empty(&sdev->starved_entry))
1361 list_add_tail(&sdev->starved_entry, &shost->starved_list);
1362 spin_unlock_irq(shost->host_lock);
1363out_dec:
1364 scsi_dec_host_busy(shost, cmd);
1365 return 0;
1366}
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380static bool scsi_mq_lld_busy(struct request_queue *q)
1381{
1382 struct scsi_device *sdev = q->queuedata;
1383 struct Scsi_Host *shost;
1384
1385 if (blk_queue_dying(q))
1386 return false;
1387
1388 shost = sdev->host;
1389
1390
1391
1392
1393
1394
1395
1396 if (scsi_host_in_recovery(shost) || scsi_device_is_busy(sdev))
1397 return true;
1398
1399 return false;
1400}
1401
1402
1403
1404
1405
1406static void scsi_complete(struct request *rq)
1407{
1408 struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq);
1409 enum scsi_disposition disposition;
1410
1411 INIT_LIST_HEAD(&cmd->eh_entry);
1412
1413 atomic_inc(&cmd->device->iodone_cnt);
1414 if (cmd->result)
1415 atomic_inc(&cmd->device->ioerr_cnt);
1416
1417 disposition = scsi_decide_disposition(cmd);
1418 if (disposition != SUCCESS && scsi_cmd_runtime_exceeced(cmd))
1419 disposition = SUCCESS;
1420
1421 scsi_log_completion(cmd, disposition);
1422
1423 switch (disposition) {
1424 case SUCCESS:
1425 scsi_finish_command(cmd);
1426 break;
1427 case NEEDS_RETRY:
1428 scsi_queue_insert(cmd, SCSI_MLQUEUE_EH_RETRY);
1429 break;
1430 case ADD_TO_MLQUEUE:
1431 scsi_queue_insert(cmd, SCSI_MLQUEUE_DEVICE_BUSY);
1432 break;
1433 default:
1434 scsi_eh_scmd_add(cmd);
1435 break;
1436 }
1437}
1438
1439
1440
1441
1442
1443
1444
1445
1446static int scsi_dispatch_cmd(struct scsi_cmnd *cmd)
1447{
1448 struct Scsi_Host *host = cmd->device->host;
1449 int rtn = 0;
1450
1451 atomic_inc(&cmd->device->iorequest_cnt);
1452
1453
1454 if (unlikely(cmd->device->sdev_state == SDEV_DEL)) {
1455
1456
1457
1458 cmd->result = DID_NO_CONNECT << 16;
1459 goto done;
1460 }
1461
1462
1463 if (unlikely(scsi_device_blocked(cmd->device))) {
1464
1465
1466
1467
1468
1469
1470
1471 SCSI_LOG_MLQUEUE(3, scmd_printk(KERN_INFO, cmd,
1472 "queuecommand : device blocked\n"));
1473 return SCSI_MLQUEUE_DEVICE_BUSY;
1474 }
1475
1476
1477 if (cmd->device->lun_in_cdb)
1478 cmd->cmnd[1] = (cmd->cmnd[1] & 0x1f) |
1479 (cmd->device->lun << 5 & 0xe0);
1480
1481 scsi_log_send(cmd);
1482
1483
1484
1485
1486
1487 if (cmd->cmd_len > cmd->device->host->max_cmd_len) {
1488 SCSI_LOG_MLQUEUE(3, scmd_printk(KERN_INFO, cmd,
1489 "queuecommand : command too long. "
1490 "cdb_size=%d host->max_cmd_len=%d\n",
1491 cmd->cmd_len, cmd->device->host->max_cmd_len));
1492 cmd->result = (DID_ABORT << 16);
1493 goto done;
1494 }
1495
1496 if (unlikely(host->shost_state == SHOST_DEL)) {
1497 cmd->result = (DID_NO_CONNECT << 16);
1498 goto done;
1499
1500 }
1501
1502 trace_scsi_dispatch_cmd_start(cmd);
1503 rtn = host->hostt->queuecommand(host, cmd);
1504 if (rtn) {
1505 trace_scsi_dispatch_cmd_error(cmd, rtn);
1506 if (rtn != SCSI_MLQUEUE_DEVICE_BUSY &&
1507 rtn != SCSI_MLQUEUE_TARGET_BUSY)
1508 rtn = SCSI_MLQUEUE_HOST_BUSY;
1509
1510 SCSI_LOG_MLQUEUE(3, scmd_printk(KERN_INFO, cmd,
1511 "queuecommand : request rejected\n"));
1512 }
1513
1514 return rtn;
1515 done:
1516 cmd->scsi_done(cmd);
1517 return 0;
1518}
1519
1520
1521static unsigned int scsi_mq_inline_sgl_size(struct Scsi_Host *shost)
1522{
1523 return min_t(unsigned int, shost->sg_tablesize, SCSI_INLINE_SG_CNT) *
1524 sizeof(struct scatterlist);
1525}
1526
1527static blk_status_t scsi_prepare_cmd(struct request *req)
1528{
1529 struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req);
1530 struct scsi_device *sdev = req->q->queuedata;
1531 struct Scsi_Host *shost = sdev->host;
1532 struct scatterlist *sg;
1533
1534 scsi_init_command(sdev, cmd);
1535
1536 cmd->request = req;
1537 cmd->tag = req->tag;
1538 cmd->prot_op = SCSI_PROT_NORMAL;
1539 if (blk_rq_bytes(req))
1540 cmd->sc_data_direction = rq_dma_dir(req);
1541 else
1542 cmd->sc_data_direction = DMA_NONE;
1543
1544 sg = (void *)cmd + sizeof(struct scsi_cmnd) + shost->hostt->cmd_size;
1545 cmd->sdb.table.sgl = sg;
1546
1547 if (scsi_host_get_prot(shost)) {
1548 memset(cmd->prot_sdb, 0, sizeof(struct scsi_data_buffer));
1549
1550 cmd->prot_sdb->table.sgl =
1551 (struct scatterlist *)(cmd->prot_sdb + 1);
1552 }
1553
1554
1555
1556
1557
1558 if (blk_rq_is_passthrough(req))
1559 return scsi_setup_scsi_cmnd(sdev, req);
1560
1561 if (sdev->handler && sdev->handler->prep_fn) {
1562 blk_status_t ret = sdev->handler->prep_fn(sdev, req);
1563
1564 if (ret != BLK_STS_OK)
1565 return ret;
1566 }
1567
1568 cmd->cmnd = scsi_req(req)->cmd = scsi_req(req)->__cmd;
1569 memset(cmd->cmnd, 0, BLK_MAX_CDB);
1570 return scsi_cmd_to_driver(cmd)->init_command(cmd);
1571}
1572
1573static void scsi_mq_done(struct scsi_cmnd *cmd)
1574{
1575 if (unlikely(blk_should_fake_timeout(cmd->request->q)))
1576 return;
1577 if (unlikely(test_and_set_bit(SCMD_STATE_COMPLETE, &cmd->state)))
1578 return;
1579 trace_scsi_dispatch_cmd_done(cmd);
1580 blk_mq_complete_request(cmd->request);
1581}
1582
1583static void scsi_mq_put_budget(struct request_queue *q, int budget_token)
1584{
1585 struct scsi_device *sdev = q->queuedata;
1586
1587 sbitmap_put(&sdev->budget_map, budget_token);
1588}
1589
1590static int scsi_mq_get_budget(struct request_queue *q)
1591{
1592 struct scsi_device *sdev = q->queuedata;
1593 int token = scsi_dev_queue_ready(q, sdev);
1594
1595 if (token >= 0)
1596 return token;
1597
1598 atomic_inc(&sdev->restarts);
1599
1600
1601
1602
1603
1604
1605 smp_mb__after_atomic();
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615 if (unlikely(scsi_device_busy(sdev) == 0 &&
1616 !scsi_device_blocked(sdev)))
1617 blk_mq_delay_run_hw_queues(sdev->request_queue, SCSI_QUEUE_DELAY);
1618 return -1;
1619}
1620
1621static void scsi_mq_set_rq_budget_token(struct request *req, int token)
1622{
1623 struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req);
1624
1625 cmd->budget_token = token;
1626}
1627
1628static int scsi_mq_get_rq_budget_token(struct request *req)
1629{
1630 struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req);
1631
1632 return cmd->budget_token;
1633}
1634
1635static blk_status_t scsi_queue_rq(struct blk_mq_hw_ctx *hctx,
1636 const struct blk_mq_queue_data *bd)
1637{
1638 struct request *req = bd->rq;
1639 struct request_queue *q = req->q;
1640 struct scsi_device *sdev = q->queuedata;
1641 struct Scsi_Host *shost = sdev->host;
1642 struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req);
1643 blk_status_t ret;
1644 int reason;
1645
1646 WARN_ON_ONCE(cmd->budget_token < 0);
1647
1648
1649
1650
1651
1652 if (unlikely(sdev->sdev_state != SDEV_RUNNING)) {
1653 ret = scsi_device_state_check(sdev, req);
1654 if (ret != BLK_STS_OK)
1655 goto out_put_budget;
1656 }
1657
1658 ret = BLK_STS_RESOURCE;
1659 if (!scsi_target_queue_ready(shost, sdev))
1660 goto out_put_budget;
1661 if (!scsi_host_queue_ready(q, shost, sdev, cmd))
1662 goto out_dec_target_busy;
1663
1664 if (!(req->rq_flags & RQF_DONTPREP)) {
1665 ret = scsi_prepare_cmd(req);
1666 if (ret != BLK_STS_OK)
1667 goto out_dec_host_busy;
1668 req->rq_flags |= RQF_DONTPREP;
1669 } else {
1670 clear_bit(SCMD_STATE_COMPLETE, &cmd->state);
1671 }
1672
1673 cmd->flags &= SCMD_PRESERVED_FLAGS;
1674 if (sdev->simple_tags)
1675 cmd->flags |= SCMD_TAGGED;
1676 if (bd->last)
1677 cmd->flags |= SCMD_LAST;
1678
1679 scsi_set_resid(cmd, 0);
1680 memset(cmd->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE);
1681 cmd->scsi_done = scsi_mq_done;
1682
1683 blk_mq_start_request(req);
1684 reason = scsi_dispatch_cmd(cmd);
1685 if (reason) {
1686 scsi_set_blocked(cmd, reason);
1687 ret = BLK_STS_RESOURCE;
1688 goto out_dec_host_busy;
1689 }
1690
1691 return BLK_STS_OK;
1692
1693out_dec_host_busy:
1694 scsi_dec_host_busy(shost, cmd);
1695out_dec_target_busy:
1696 if (scsi_target(sdev)->can_queue > 0)
1697 atomic_dec(&scsi_target(sdev)->target_busy);
1698out_put_budget:
1699 scsi_mq_put_budget(q, cmd->budget_token);
1700 cmd->budget_token = -1;
1701 switch (ret) {
1702 case BLK_STS_OK:
1703 break;
1704 case BLK_STS_RESOURCE:
1705 case BLK_STS_ZONE_RESOURCE:
1706 if (scsi_device_blocked(sdev))
1707 ret = BLK_STS_DEV_RESOURCE;
1708 break;
1709 case BLK_STS_AGAIN:
1710 scsi_req(req)->result = DID_BUS_BUSY << 16;
1711 if (req->rq_flags & RQF_DONTPREP)
1712 scsi_mq_uninit_cmd(cmd);
1713 break;
1714 default:
1715 if (unlikely(!scsi_device_online(sdev)))
1716 scsi_req(req)->result = DID_NO_CONNECT << 16;
1717 else
1718 scsi_req(req)->result = DID_ERROR << 16;
1719
1720
1721
1722
1723
1724 if (req->rq_flags & RQF_DONTPREP)
1725 scsi_mq_uninit_cmd(cmd);
1726 scsi_run_queue_async(sdev);
1727 break;
1728 }
1729 return ret;
1730}
1731
1732static enum blk_eh_timer_return scsi_timeout(struct request *req,
1733 bool reserved)
1734{
1735 if (reserved)
1736 return BLK_EH_RESET_TIMER;
1737 return scsi_times_out(req);
1738}
1739
1740static int scsi_mq_init_request(struct blk_mq_tag_set *set, struct request *rq,
1741 unsigned int hctx_idx, unsigned int numa_node)
1742{
1743 struct Scsi_Host *shost = set->driver_data;
1744 struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq);
1745 struct scatterlist *sg;
1746 int ret = 0;
1747
1748 cmd->sense_buffer =
1749 kmem_cache_alloc_node(scsi_sense_cache, GFP_KERNEL, numa_node);
1750 if (!cmd->sense_buffer)
1751 return -ENOMEM;
1752 cmd->req.sense = cmd->sense_buffer;
1753
1754 if (scsi_host_get_prot(shost)) {
1755 sg = (void *)cmd + sizeof(struct scsi_cmnd) +
1756 shost->hostt->cmd_size;
1757 cmd->prot_sdb = (void *)sg + scsi_mq_inline_sgl_size(shost);
1758 }
1759
1760 if (shost->hostt->init_cmd_priv) {
1761 ret = shost->hostt->init_cmd_priv(shost, cmd);
1762 if (ret < 0)
1763 kmem_cache_free(scsi_sense_cache, cmd->sense_buffer);
1764 }
1765
1766 return ret;
1767}
1768
1769static void scsi_mq_exit_request(struct blk_mq_tag_set *set, struct request *rq,
1770 unsigned int hctx_idx)
1771{
1772 struct Scsi_Host *shost = set->driver_data;
1773 struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq);
1774
1775 if (shost->hostt->exit_cmd_priv)
1776 shost->hostt->exit_cmd_priv(shost, cmd);
1777 kmem_cache_free(scsi_sense_cache, cmd->sense_buffer);
1778}
1779
1780
1781static int scsi_mq_poll(struct blk_mq_hw_ctx *hctx)
1782{
1783 struct Scsi_Host *shost = hctx->driver_data;
1784
1785 if (shost->hostt->mq_poll)
1786 return shost->hostt->mq_poll(shost, hctx->queue_num);
1787
1788 return 0;
1789}
1790
1791static int scsi_init_hctx(struct blk_mq_hw_ctx *hctx, void *data,
1792 unsigned int hctx_idx)
1793{
1794 struct Scsi_Host *shost = data;
1795
1796 hctx->driver_data = shost;
1797 return 0;
1798}
1799
1800static int scsi_map_queues(struct blk_mq_tag_set *set)
1801{
1802 struct Scsi_Host *shost = container_of(set, struct Scsi_Host, tag_set);
1803
1804 if (shost->hostt->map_queues)
1805 return shost->hostt->map_queues(shost);
1806 return blk_mq_map_queues(&set->map[HCTX_TYPE_DEFAULT]);
1807}
1808
1809void __scsi_init_queue(struct Scsi_Host *shost, struct request_queue *q)
1810{
1811 struct device *dev = shost->dma_dev;
1812
1813
1814
1815
1816 blk_queue_max_segments(q, min_t(unsigned short, shost->sg_tablesize,
1817 SG_MAX_SEGMENTS));
1818
1819 if (scsi_host_prot_dma(shost)) {
1820 shost->sg_prot_tablesize =
1821 min_not_zero(shost->sg_prot_tablesize,
1822 (unsigned short)SCSI_MAX_PROT_SG_SEGMENTS);
1823 BUG_ON(shost->sg_prot_tablesize < shost->sg_tablesize);
1824 blk_queue_max_integrity_segments(q, shost->sg_prot_tablesize);
1825 }
1826
1827 if (dev->dma_mask) {
1828 shost->max_sectors = min_t(unsigned int, shost->max_sectors,
1829 dma_max_mapping_size(dev) >> SECTOR_SHIFT);
1830 }
1831 blk_queue_max_hw_sectors(q, shost->max_sectors);
1832 blk_queue_segment_boundary(q, shost->dma_boundary);
1833 dma_set_seg_boundary(dev, shost->dma_boundary);
1834
1835 blk_queue_max_segment_size(q, shost->max_segment_size);
1836 blk_queue_virt_boundary(q, shost->virt_boundary_mask);
1837 dma_set_max_seg_size(dev, queue_max_segment_size(q));
1838
1839
1840
1841
1842
1843
1844
1845
1846 blk_queue_dma_alignment(q, max(4, dma_get_cache_alignment()) - 1);
1847}
1848EXPORT_SYMBOL_GPL(__scsi_init_queue);
1849
1850static const struct blk_mq_ops scsi_mq_ops_no_commit = {
1851 .get_budget = scsi_mq_get_budget,
1852 .put_budget = scsi_mq_put_budget,
1853 .queue_rq = scsi_queue_rq,
1854 .complete = scsi_complete,
1855 .timeout = scsi_timeout,
1856#ifdef CONFIG_BLK_DEBUG_FS
1857 .show_rq = scsi_show_rq,
1858#endif
1859 .init_request = scsi_mq_init_request,
1860 .exit_request = scsi_mq_exit_request,
1861 .initialize_rq_fn = scsi_initialize_rq,
1862 .cleanup_rq = scsi_cleanup_rq,
1863 .busy = scsi_mq_lld_busy,
1864 .map_queues = scsi_map_queues,
1865 .init_hctx = scsi_init_hctx,
1866 .poll = scsi_mq_poll,
1867 .set_rq_budget_token = scsi_mq_set_rq_budget_token,
1868 .get_rq_budget_token = scsi_mq_get_rq_budget_token,
1869};
1870
1871
1872static void scsi_commit_rqs(struct blk_mq_hw_ctx *hctx)
1873{
1874 struct Scsi_Host *shost = hctx->driver_data;
1875
1876 shost->hostt->commit_rqs(shost, hctx->queue_num);
1877}
1878
1879static const struct blk_mq_ops scsi_mq_ops = {
1880 .get_budget = scsi_mq_get_budget,
1881 .put_budget = scsi_mq_put_budget,
1882 .queue_rq = scsi_queue_rq,
1883 .commit_rqs = scsi_commit_rqs,
1884 .complete = scsi_complete,
1885 .timeout = scsi_timeout,
1886#ifdef CONFIG_BLK_DEBUG_FS
1887 .show_rq = scsi_show_rq,
1888#endif
1889 .init_request = scsi_mq_init_request,
1890 .exit_request = scsi_mq_exit_request,
1891 .initialize_rq_fn = scsi_initialize_rq,
1892 .cleanup_rq = scsi_cleanup_rq,
1893 .busy = scsi_mq_lld_busy,
1894 .map_queues = scsi_map_queues,
1895 .init_hctx = scsi_init_hctx,
1896 .poll = scsi_mq_poll,
1897 .set_rq_budget_token = scsi_mq_set_rq_budget_token,
1898 .get_rq_budget_token = scsi_mq_get_rq_budget_token,
1899};
1900
1901int scsi_mq_setup_tags(struct Scsi_Host *shost)
1902{
1903 unsigned int cmd_size, sgl_size;
1904 struct blk_mq_tag_set *tag_set = &shost->tag_set;
1905
1906 sgl_size = max_t(unsigned int, sizeof(struct scatterlist),
1907 scsi_mq_inline_sgl_size(shost));
1908 cmd_size = sizeof(struct scsi_cmnd) + shost->hostt->cmd_size + sgl_size;
1909 if (scsi_host_get_prot(shost))
1910 cmd_size += sizeof(struct scsi_data_buffer) +
1911 sizeof(struct scatterlist) * SCSI_INLINE_PROT_SG_CNT;
1912
1913 memset(tag_set, 0, sizeof(*tag_set));
1914 if (shost->hostt->commit_rqs)
1915 tag_set->ops = &scsi_mq_ops;
1916 else
1917 tag_set->ops = &scsi_mq_ops_no_commit;
1918 tag_set->nr_hw_queues = shost->nr_hw_queues ? : 1;
1919 tag_set->nr_maps = shost->nr_maps ? : 1;
1920 tag_set->queue_depth = shost->can_queue;
1921 tag_set->cmd_size = cmd_size;
1922 tag_set->numa_node = NUMA_NO_NODE;
1923 tag_set->flags = BLK_MQ_F_SHOULD_MERGE;
1924 tag_set->flags |=
1925 BLK_ALLOC_POLICY_TO_MQ_FLAG(shost->hostt->tag_alloc_policy);
1926 tag_set->driver_data = shost;
1927 if (shost->host_tagset)
1928 tag_set->flags |= BLK_MQ_F_TAG_HCTX_SHARED;
1929
1930 return blk_mq_alloc_tag_set(tag_set);
1931}
1932
1933void scsi_mq_destroy_tags(struct Scsi_Host *shost)
1934{
1935 blk_mq_free_tag_set(&shost->tag_set);
1936}
1937
1938
1939
1940
1941
1942
1943
1944
1945struct scsi_device *scsi_device_from_queue(struct request_queue *q)
1946{
1947 struct scsi_device *sdev = NULL;
1948
1949 if (q->mq_ops == &scsi_mq_ops_no_commit ||
1950 q->mq_ops == &scsi_mq_ops)
1951 sdev = q->queuedata;
1952 if (!sdev || !get_device(&sdev->sdev_gendev))
1953 sdev = NULL;
1954
1955 return sdev;
1956}
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966void scsi_block_requests(struct Scsi_Host *shost)
1967{
1968 shost->host_self_blocked = 1;
1969}
1970EXPORT_SYMBOL(scsi_block_requests);
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982void scsi_unblock_requests(struct Scsi_Host *shost)
1983{
1984 shost->host_self_blocked = 0;
1985 scsi_run_host_queues(shost);
1986}
1987EXPORT_SYMBOL(scsi_unblock_requests);
1988
1989void scsi_exit_queue(void)
1990{
1991 kmem_cache_destroy(scsi_sense_cache);
1992}
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012int
2013scsi_mode_select(struct scsi_device *sdev, int pf, int sp, int modepage,
2014 unsigned char *buffer, int len, int timeout, int retries,
2015 struct scsi_mode_data *data, struct scsi_sense_hdr *sshdr)
2016{
2017 unsigned char cmd[10];
2018 unsigned char *real_buffer;
2019 int ret;
2020
2021 memset(cmd, 0, sizeof(cmd));
2022 cmd[1] = (pf ? 0x10 : 0) | (sp ? 0x01 : 0);
2023
2024 if (sdev->use_10_for_ms) {
2025 if (len > 65535)
2026 return -EINVAL;
2027 real_buffer = kmalloc(8 + len, GFP_KERNEL);
2028 if (!real_buffer)
2029 return -ENOMEM;
2030 memcpy(real_buffer + 8, buffer, len);
2031 len += 8;
2032 real_buffer[0] = 0;
2033 real_buffer[1] = 0;
2034 real_buffer[2] = data->medium_type;
2035 real_buffer[3] = data->device_specific;
2036 real_buffer[4] = data->longlba ? 0x01 : 0;
2037 real_buffer[5] = 0;
2038 real_buffer[6] = data->block_descriptor_length >> 8;
2039 real_buffer[7] = data->block_descriptor_length;
2040
2041 cmd[0] = MODE_SELECT_10;
2042 cmd[7] = len >> 8;
2043 cmd[8] = len;
2044 } else {
2045 if (len > 255 || data->block_descriptor_length > 255 ||
2046 data->longlba)
2047 return -EINVAL;
2048
2049 real_buffer = kmalloc(4 + len, GFP_KERNEL);
2050 if (!real_buffer)
2051 return -ENOMEM;
2052 memcpy(real_buffer + 4, buffer, len);
2053 len += 4;
2054 real_buffer[0] = 0;
2055 real_buffer[1] = data->medium_type;
2056 real_buffer[2] = data->device_specific;
2057 real_buffer[3] = data->block_descriptor_length;
2058
2059 cmd[0] = MODE_SELECT;
2060 cmd[4] = len;
2061 }
2062
2063 ret = scsi_execute_req(sdev, cmd, DMA_TO_DEVICE, real_buffer, len,
2064 sshdr, timeout, retries, NULL);
2065 kfree(real_buffer);
2066 return ret;
2067}
2068EXPORT_SYMBOL_GPL(scsi_mode_select);
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085int
2086scsi_mode_sense(struct scsi_device *sdev, int dbd, int modepage,
2087 unsigned char *buffer, int len, int timeout, int retries,
2088 struct scsi_mode_data *data, struct scsi_sense_hdr *sshdr)
2089{
2090 unsigned char cmd[12];
2091 int use_10_for_ms;
2092 int header_length;
2093 int result, retry_count = retries;
2094 struct scsi_sense_hdr my_sshdr;
2095
2096 memset(data, 0, sizeof(*data));
2097 memset(&cmd[0], 0, 12);
2098
2099 dbd = sdev->set_dbd_for_ms ? 8 : dbd;
2100 cmd[1] = dbd & 0x18;
2101 cmd[2] = modepage;
2102
2103
2104 if (!sshdr)
2105 sshdr = &my_sshdr;
2106
2107 retry:
2108 use_10_for_ms = sdev->use_10_for_ms;
2109
2110 if (use_10_for_ms) {
2111 if (len < 8)
2112 len = 8;
2113
2114 cmd[0] = MODE_SENSE_10;
2115 cmd[8] = len;
2116 header_length = 8;
2117 } else {
2118 if (len < 4)
2119 len = 4;
2120
2121 cmd[0] = MODE_SENSE;
2122 cmd[4] = len;
2123 header_length = 4;
2124 }
2125
2126 memset(buffer, 0, len);
2127
2128 result = scsi_execute_req(sdev, cmd, DMA_FROM_DEVICE, buffer, len,
2129 sshdr, timeout, retries, NULL);
2130 if (result < 0)
2131 return result;
2132
2133
2134
2135
2136
2137
2138 if (!scsi_status_is_good(result)) {
2139 if (scsi_sense_valid(sshdr)) {
2140 if ((sshdr->sense_key == ILLEGAL_REQUEST) &&
2141 (sshdr->asc == 0x20) && (sshdr->ascq == 0)) {
2142
2143
2144
2145 if (use_10_for_ms) {
2146 sdev->use_10_for_ms = 0;
2147 goto retry;
2148 }
2149 }
2150 if (scsi_status_is_check_condition(result) &&
2151 sshdr->sense_key == UNIT_ATTENTION &&
2152 retry_count) {
2153 retry_count--;
2154 goto retry;
2155 }
2156 }
2157 return -EIO;
2158 }
2159 if (unlikely(buffer[0] == 0x86 && buffer[1] == 0x0b &&
2160 (modepage == 6 || modepage == 8))) {
2161
2162 header_length = 0;
2163 data->length = 13;
2164 data->medium_type = 0;
2165 data->device_specific = 0;
2166 data->longlba = 0;
2167 data->block_descriptor_length = 0;
2168 } else if (use_10_for_ms) {
2169 data->length = buffer[0]*256 + buffer[1] + 2;
2170 data->medium_type = buffer[2];
2171 data->device_specific = buffer[3];
2172 data->longlba = buffer[4] & 0x01;
2173 data->block_descriptor_length = buffer[6]*256
2174 + buffer[7];
2175 } else {
2176 data->length = buffer[0] + 1;
2177 data->medium_type = buffer[1];
2178 data->device_specific = buffer[2];
2179 data->block_descriptor_length = buffer[3];
2180 }
2181 data->header_length = header_length;
2182
2183 return 0;
2184}
2185EXPORT_SYMBOL(scsi_mode_sense);
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197int
2198scsi_test_unit_ready(struct scsi_device *sdev, int timeout, int retries,
2199 struct scsi_sense_hdr *sshdr)
2200{
2201 char cmd[] = {
2202 TEST_UNIT_READY, 0, 0, 0, 0, 0,
2203 };
2204 int result;
2205
2206
2207 do {
2208 result = scsi_execute_req(sdev, cmd, DMA_NONE, NULL, 0, sshdr,
2209 timeout, 1, NULL);
2210 if (sdev->removable && scsi_sense_valid(sshdr) &&
2211 sshdr->sense_key == UNIT_ATTENTION)
2212 sdev->changed = 1;
2213 } while (scsi_sense_valid(sshdr) &&
2214 sshdr->sense_key == UNIT_ATTENTION && --retries);
2215
2216 return result;
2217}
2218EXPORT_SYMBOL(scsi_test_unit_ready);
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228int
2229scsi_device_set_state(struct scsi_device *sdev, enum scsi_device_state state)
2230{
2231 enum scsi_device_state oldstate = sdev->sdev_state;
2232
2233 if (state == oldstate)
2234 return 0;
2235
2236 switch (state) {
2237 case SDEV_CREATED:
2238 switch (oldstate) {
2239 case SDEV_CREATED_BLOCK:
2240 break;
2241 default:
2242 goto illegal;
2243 }
2244 break;
2245
2246 case SDEV_RUNNING:
2247 switch (oldstate) {
2248 case SDEV_CREATED:
2249 case SDEV_OFFLINE:
2250 case SDEV_TRANSPORT_OFFLINE:
2251 case SDEV_QUIESCE:
2252 case SDEV_BLOCK:
2253 break;
2254 default:
2255 goto illegal;
2256 }
2257 break;
2258
2259 case SDEV_QUIESCE:
2260 switch (oldstate) {
2261 case SDEV_RUNNING:
2262 case SDEV_OFFLINE:
2263 case SDEV_TRANSPORT_OFFLINE:
2264 break;
2265 default:
2266 goto illegal;
2267 }
2268 break;
2269
2270 case SDEV_OFFLINE:
2271 case SDEV_TRANSPORT_OFFLINE:
2272 switch (oldstate) {
2273 case SDEV_CREATED:
2274 case SDEV_RUNNING:
2275 case SDEV_QUIESCE:
2276 case SDEV_BLOCK:
2277 break;
2278 default:
2279 goto illegal;
2280 }
2281 break;
2282
2283 case SDEV_BLOCK:
2284 switch (oldstate) {
2285 case SDEV_RUNNING:
2286 case SDEV_CREATED_BLOCK:
2287 case SDEV_QUIESCE:
2288 case SDEV_OFFLINE:
2289 break;
2290 default:
2291 goto illegal;
2292 }
2293 break;
2294
2295 case SDEV_CREATED_BLOCK:
2296 switch (oldstate) {
2297 case SDEV_CREATED:
2298 break;
2299 default:
2300 goto illegal;
2301 }
2302 break;
2303
2304 case SDEV_CANCEL:
2305 switch (oldstate) {
2306 case SDEV_CREATED:
2307 case SDEV_RUNNING:
2308 case SDEV_QUIESCE:
2309 case SDEV_OFFLINE:
2310 case SDEV_TRANSPORT_OFFLINE:
2311 break;
2312 default:
2313 goto illegal;
2314 }
2315 break;
2316
2317 case SDEV_DEL:
2318 switch (oldstate) {
2319 case SDEV_CREATED:
2320 case SDEV_RUNNING:
2321 case SDEV_OFFLINE:
2322 case SDEV_TRANSPORT_OFFLINE:
2323 case SDEV_CANCEL:
2324 case SDEV_BLOCK:
2325 case SDEV_CREATED_BLOCK:
2326 break;
2327 default:
2328 goto illegal;
2329 }
2330 break;
2331
2332 }
2333 sdev->offline_already = false;
2334 sdev->sdev_state = state;
2335 return 0;
2336
2337 illegal:
2338 SCSI_LOG_ERROR_RECOVERY(1,
2339 sdev_printk(KERN_ERR, sdev,
2340 "Illegal state transition %s->%s",
2341 scsi_device_state_name(oldstate),
2342 scsi_device_state_name(state))
2343 );
2344 return -EINVAL;
2345}
2346EXPORT_SYMBOL(scsi_device_set_state);
2347
2348
2349
2350
2351
2352
2353
2354
2355static void scsi_evt_emit(struct scsi_device *sdev, struct scsi_event *evt)
2356{
2357 int idx = 0;
2358 char *envp[3];
2359
2360 switch (evt->evt_type) {
2361 case SDEV_EVT_MEDIA_CHANGE:
2362 envp[idx++] = "SDEV_MEDIA_CHANGE=1";
2363 break;
2364 case SDEV_EVT_INQUIRY_CHANGE_REPORTED:
2365 scsi_rescan_device(&sdev->sdev_gendev);
2366 envp[idx++] = "SDEV_UA=INQUIRY_DATA_HAS_CHANGED";
2367 break;
2368 case SDEV_EVT_CAPACITY_CHANGE_REPORTED:
2369 envp[idx++] = "SDEV_UA=CAPACITY_DATA_HAS_CHANGED";
2370 break;
2371 case SDEV_EVT_SOFT_THRESHOLD_REACHED_REPORTED:
2372 envp[idx++] = "SDEV_UA=THIN_PROVISIONING_SOFT_THRESHOLD_REACHED";
2373 break;
2374 case SDEV_EVT_MODE_PARAMETER_CHANGE_REPORTED:
2375 envp[idx++] = "SDEV_UA=MODE_PARAMETERS_CHANGED";
2376 break;
2377 case SDEV_EVT_LUN_CHANGE_REPORTED:
2378 envp[idx++] = "SDEV_UA=REPORTED_LUNS_DATA_HAS_CHANGED";
2379 break;
2380 case SDEV_EVT_ALUA_STATE_CHANGE_REPORTED:
2381 envp[idx++] = "SDEV_UA=ASYMMETRIC_ACCESS_STATE_CHANGED";
2382 break;
2383 case SDEV_EVT_POWER_ON_RESET_OCCURRED:
2384 envp[idx++] = "SDEV_UA=POWER_ON_RESET_OCCURRED";
2385 break;
2386 default:
2387
2388 break;
2389 }
2390
2391 envp[idx++] = NULL;
2392
2393 kobject_uevent_env(&sdev->sdev_gendev.kobj, KOBJ_CHANGE, envp);
2394}
2395
2396
2397
2398
2399
2400
2401
2402
2403void scsi_evt_thread(struct work_struct *work)
2404{
2405 struct scsi_device *sdev;
2406 enum scsi_device_event evt_type;
2407 LIST_HEAD(event_list);
2408
2409 sdev = container_of(work, struct scsi_device, event_work);
2410
2411 for (evt_type = SDEV_EVT_FIRST; evt_type <= SDEV_EVT_LAST; evt_type++)
2412 if (test_and_clear_bit(evt_type, sdev->pending_events))
2413 sdev_evt_send_simple(sdev, evt_type, GFP_KERNEL);
2414
2415 while (1) {
2416 struct scsi_event *evt;
2417 struct list_head *this, *tmp;
2418 unsigned long flags;
2419
2420 spin_lock_irqsave(&sdev->list_lock, flags);
2421 list_splice_init(&sdev->event_list, &event_list);
2422 spin_unlock_irqrestore(&sdev->list_lock, flags);
2423
2424 if (list_empty(&event_list))
2425 break;
2426
2427 list_for_each_safe(this, tmp, &event_list) {
2428 evt = list_entry(this, struct scsi_event, node);
2429 list_del(&evt->node);
2430 scsi_evt_emit(sdev, evt);
2431 kfree(evt);
2432 }
2433 }
2434}
2435
2436
2437
2438
2439
2440
2441
2442
2443void sdev_evt_send(struct scsi_device *sdev, struct scsi_event *evt)
2444{
2445 unsigned long flags;
2446
2447#if 0
2448
2449
2450
2451 if (!test_bit(evt->evt_type, sdev->supported_events)) {
2452 kfree(evt);
2453 return;
2454 }
2455#endif
2456
2457 spin_lock_irqsave(&sdev->list_lock, flags);
2458 list_add_tail(&evt->node, &sdev->event_list);
2459 schedule_work(&sdev->event_work);
2460 spin_unlock_irqrestore(&sdev->list_lock, flags);
2461}
2462EXPORT_SYMBOL_GPL(sdev_evt_send);
2463
2464
2465
2466
2467
2468
2469
2470
2471struct scsi_event *sdev_evt_alloc(enum scsi_device_event evt_type,
2472 gfp_t gfpflags)
2473{
2474 struct scsi_event *evt = kzalloc(sizeof(struct scsi_event), gfpflags);
2475 if (!evt)
2476 return NULL;
2477
2478 evt->evt_type = evt_type;
2479 INIT_LIST_HEAD(&evt->node);
2480
2481
2482 switch (evt_type) {
2483 case SDEV_EVT_MEDIA_CHANGE:
2484 case SDEV_EVT_INQUIRY_CHANGE_REPORTED:
2485 case SDEV_EVT_CAPACITY_CHANGE_REPORTED:
2486 case SDEV_EVT_SOFT_THRESHOLD_REACHED_REPORTED:
2487 case SDEV_EVT_MODE_PARAMETER_CHANGE_REPORTED:
2488 case SDEV_EVT_LUN_CHANGE_REPORTED:
2489 case SDEV_EVT_ALUA_STATE_CHANGE_REPORTED:
2490 case SDEV_EVT_POWER_ON_RESET_OCCURRED:
2491 default:
2492
2493 break;
2494 }
2495
2496 return evt;
2497}
2498EXPORT_SYMBOL_GPL(sdev_evt_alloc);
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508void sdev_evt_send_simple(struct scsi_device *sdev,
2509 enum scsi_device_event evt_type, gfp_t gfpflags)
2510{
2511 struct scsi_event *evt = sdev_evt_alloc(evt_type, gfpflags);
2512 if (!evt) {
2513 sdev_printk(KERN_ERR, sdev, "event %d eaten due to OOM\n",
2514 evt_type);
2515 return;
2516 }
2517
2518 sdev_evt_send(sdev, evt);
2519}
2520EXPORT_SYMBOL_GPL(sdev_evt_send_simple);
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535int
2536scsi_device_quiesce(struct scsi_device *sdev)
2537{
2538 struct request_queue *q = sdev->request_queue;
2539 int err;
2540
2541
2542
2543
2544
2545
2546 WARN_ON_ONCE(sdev->quiesced_by && sdev->quiesced_by != current);
2547
2548 if (sdev->quiesced_by == current)
2549 return 0;
2550
2551 blk_set_pm_only(q);
2552
2553 blk_mq_freeze_queue(q);
2554
2555
2556
2557
2558
2559
2560 synchronize_rcu();
2561 blk_mq_unfreeze_queue(q);
2562
2563 mutex_lock(&sdev->state_mutex);
2564 err = scsi_device_set_state(sdev, SDEV_QUIESCE);
2565 if (err == 0)
2566 sdev->quiesced_by = current;
2567 else
2568 blk_clear_pm_only(q);
2569 mutex_unlock(&sdev->state_mutex);
2570
2571 return err;
2572}
2573EXPORT_SYMBOL(scsi_device_quiesce);
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584void scsi_device_resume(struct scsi_device *sdev)
2585{
2586
2587
2588
2589
2590 mutex_lock(&sdev->state_mutex);
2591 if (sdev->sdev_state == SDEV_QUIESCE)
2592 scsi_device_set_state(sdev, SDEV_RUNNING);
2593 if (sdev->quiesced_by) {
2594 sdev->quiesced_by = NULL;
2595 blk_clear_pm_only(sdev->request_queue);
2596 }
2597 mutex_unlock(&sdev->state_mutex);
2598}
2599EXPORT_SYMBOL(scsi_device_resume);
2600
2601static void
2602device_quiesce_fn(struct scsi_device *sdev, void *data)
2603{
2604 scsi_device_quiesce(sdev);
2605}
2606
2607void
2608scsi_target_quiesce(struct scsi_target *starget)
2609{
2610 starget_for_each_device(starget, NULL, device_quiesce_fn);
2611}
2612EXPORT_SYMBOL(scsi_target_quiesce);
2613
2614static void
2615device_resume_fn(struct scsi_device *sdev, void *data)
2616{
2617 scsi_device_resume(sdev);
2618}
2619
2620void
2621scsi_target_resume(struct scsi_target *starget)
2622{
2623 starget_for_each_device(starget, NULL, device_resume_fn);
2624}
2625EXPORT_SYMBOL(scsi_target_resume);
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641int scsi_internal_device_block_nowait(struct scsi_device *sdev)
2642{
2643 struct request_queue *q = sdev->request_queue;
2644 int err = 0;
2645
2646 err = scsi_device_set_state(sdev, SDEV_BLOCK);
2647 if (err) {
2648 err = scsi_device_set_state(sdev, SDEV_CREATED_BLOCK);
2649
2650 if (err)
2651 return err;
2652 }
2653
2654
2655
2656
2657
2658
2659 blk_mq_quiesce_queue_nowait(q);
2660 return 0;
2661}
2662EXPORT_SYMBOL_GPL(scsi_internal_device_block_nowait);
2663
2664
2665
2666
2667
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679static int scsi_internal_device_block(struct scsi_device *sdev)
2680{
2681 struct request_queue *q = sdev->request_queue;
2682 int err;
2683
2684 mutex_lock(&sdev->state_mutex);
2685 err = scsi_internal_device_block_nowait(sdev);
2686 if (err == 0)
2687 blk_mq_quiesce_queue(q);
2688 mutex_unlock(&sdev->state_mutex);
2689
2690 return err;
2691}
2692
2693void scsi_start_queue(struct scsi_device *sdev)
2694{
2695 struct request_queue *q = sdev->request_queue;
2696
2697 blk_mq_unquiesce_queue(q);
2698}
2699
2700
2701
2702
2703
2704
2705
2706
2707
2708
2709
2710
2711
2712
2713
2714
2715int scsi_internal_device_unblock_nowait(struct scsi_device *sdev,
2716 enum scsi_device_state new_state)
2717{
2718 switch (new_state) {
2719 case SDEV_RUNNING:
2720 case SDEV_TRANSPORT_OFFLINE:
2721 break;
2722 default:
2723 return -EINVAL;
2724 }
2725
2726
2727
2728
2729
2730 switch (sdev->sdev_state) {
2731 case SDEV_BLOCK:
2732 case SDEV_TRANSPORT_OFFLINE:
2733 sdev->sdev_state = new_state;
2734 break;
2735 case SDEV_CREATED_BLOCK:
2736 if (new_state == SDEV_TRANSPORT_OFFLINE ||
2737 new_state == SDEV_OFFLINE)
2738 sdev->sdev_state = new_state;
2739 else
2740 sdev->sdev_state = SDEV_CREATED;
2741 break;
2742 case SDEV_CANCEL:
2743 case SDEV_OFFLINE:
2744 break;
2745 default:
2746 return -EINVAL;
2747 }
2748 scsi_start_queue(sdev);
2749
2750 return 0;
2751}
2752EXPORT_SYMBOL_GPL(scsi_internal_device_unblock_nowait);
2753
2754
2755
2756
2757
2758
2759
2760
2761
2762
2763
2764
2765
2766
2767
2768static int scsi_internal_device_unblock(struct scsi_device *sdev,
2769 enum scsi_device_state new_state)
2770{
2771 int ret;
2772
2773 mutex_lock(&sdev->state_mutex);
2774 ret = scsi_internal_device_unblock_nowait(sdev, new_state);
2775 mutex_unlock(&sdev->state_mutex);
2776
2777 return ret;
2778}
2779
2780static void
2781device_block(struct scsi_device *sdev, void *data)
2782{
2783 int ret;
2784
2785 ret = scsi_internal_device_block(sdev);
2786
2787 WARN_ONCE(ret, "scsi_internal_device_block(%s) failed: ret = %d\n",
2788 dev_name(&sdev->sdev_gendev), ret);
2789}
2790
2791static int
2792target_block(struct device *dev, void *data)
2793{
2794 if (scsi_is_target_device(dev))
2795 starget_for_each_device(to_scsi_target(dev), NULL,
2796 device_block);
2797 return 0;
2798}
2799
2800void
2801scsi_target_block(struct device *dev)
2802{
2803 if (scsi_is_target_device(dev))
2804 starget_for_each_device(to_scsi_target(dev), NULL,
2805 device_block);
2806 else
2807 device_for_each_child(dev, NULL, target_block);
2808}
2809EXPORT_SYMBOL_GPL(scsi_target_block);
2810
2811static void
2812device_unblock(struct scsi_device *sdev, void *data)
2813{
2814 scsi_internal_device_unblock(sdev, *(enum scsi_device_state *)data);
2815}
2816
2817static int
2818target_unblock(struct device *dev, void *data)
2819{
2820 if (scsi_is_target_device(dev))
2821 starget_for_each_device(to_scsi_target(dev), data,
2822 device_unblock);
2823 return 0;
2824}
2825
2826void
2827scsi_target_unblock(struct device *dev, enum scsi_device_state new_state)
2828{
2829 if (scsi_is_target_device(dev))
2830 starget_for_each_device(to_scsi_target(dev), &new_state,
2831 device_unblock);
2832 else
2833 device_for_each_child(dev, &new_state, target_unblock);
2834}
2835EXPORT_SYMBOL_GPL(scsi_target_unblock);
2836
2837int
2838scsi_host_block(struct Scsi_Host *shost)
2839{
2840 struct scsi_device *sdev;
2841 int ret = 0;
2842
2843
2844
2845
2846
2847 shost_for_each_device(sdev, shost) {
2848 mutex_lock(&sdev->state_mutex);
2849 ret = scsi_internal_device_block_nowait(sdev);
2850 mutex_unlock(&sdev->state_mutex);
2851 if (ret) {
2852 scsi_device_put(sdev);
2853 break;
2854 }
2855 }
2856
2857
2858
2859
2860
2861 WARN_ON_ONCE(shost->tag_set.flags & BLK_MQ_F_BLOCKING);
2862
2863 if (!ret)
2864 synchronize_rcu();
2865
2866 return ret;
2867}
2868EXPORT_SYMBOL_GPL(scsi_host_block);
2869
2870int
2871scsi_host_unblock(struct Scsi_Host *shost, int new_state)
2872{
2873 struct scsi_device *sdev;
2874 int ret = 0;
2875
2876 shost_for_each_device(sdev, shost) {
2877 ret = scsi_internal_device_unblock(sdev, new_state);
2878 if (ret) {
2879 scsi_device_put(sdev);
2880 break;
2881 }
2882 }
2883 return ret;
2884}
2885EXPORT_SYMBOL_GPL(scsi_host_unblock);
2886
2887
2888
2889
2890
2891
2892
2893
2894
2895
2896void *scsi_kmap_atomic_sg(struct scatterlist *sgl, int sg_count,
2897 size_t *offset, size_t *len)
2898{
2899 int i;
2900 size_t sg_len = 0, len_complete = 0;
2901 struct scatterlist *sg;
2902 struct page *page;
2903
2904 WARN_ON(!irqs_disabled());
2905
2906 for_each_sg(sgl, sg, sg_count, i) {
2907 len_complete = sg_len;
2908 sg_len += sg->length;
2909 if (sg_len > *offset)
2910 break;
2911 }
2912
2913 if (unlikely(i == sg_count)) {
2914 printk(KERN_ERR "%s: Bytes in sg: %zu, requested offset %zu, "
2915 "elements %d\n",
2916 __func__, sg_len, *offset, sg_count);
2917 WARN_ON(1);
2918 return NULL;
2919 }
2920
2921
2922 *offset = *offset - len_complete + sg->offset;
2923
2924
2925 page = nth_page(sg_page(sg), (*offset >> PAGE_SHIFT));
2926 *offset &= ~PAGE_MASK;
2927
2928
2929 sg_len = PAGE_SIZE - *offset;
2930 if (*len > sg_len)
2931 *len = sg_len;
2932
2933 return kmap_atomic(page);
2934}
2935EXPORT_SYMBOL(scsi_kmap_atomic_sg);
2936
2937
2938
2939
2940
2941void scsi_kunmap_atomic_sg(void *virt)
2942{
2943 kunmap_atomic(virt);
2944}
2945EXPORT_SYMBOL(scsi_kunmap_atomic_sg);
2946
2947void sdev_disable_disk_events(struct scsi_device *sdev)
2948{
2949 atomic_inc(&sdev->disk_events_disable_depth);
2950}
2951EXPORT_SYMBOL(sdev_disable_disk_events);
2952
2953void sdev_enable_disk_events(struct scsi_device *sdev)
2954{
2955 if (WARN_ON_ONCE(atomic_read(&sdev->disk_events_disable_depth) <= 0))
2956 return;
2957 atomic_dec(&sdev->disk_events_disable_depth);
2958}
2959EXPORT_SYMBOL(sdev_enable_disk_events);
2960
2961static unsigned char designator_prio(const unsigned char *d)
2962{
2963 if (d[1] & 0x30)
2964
2965 return 0;
2966
2967 if (d[3] == 0)
2968
2969 return 0;
2970
2971
2972
2973
2974
2975
2976
2977
2978
2979
2980
2981
2982
2983
2984
2985
2986 switch (d[1] & 0xf) {
2987 case 8:
2988
2989 return 9;
2990 case 3:
2991 switch (d[4] >> 4) {
2992 case 6:
2993
2994 return 8;
2995 case 5:
2996
2997 return 5;
2998 case 4:
2999
3000 return 4;
3001 case 3:
3002
3003 return 1;
3004 default:
3005 break;
3006 }
3007 break;
3008 case 2:
3009 switch (d[3]) {
3010 case 16:
3011
3012 return 7;
3013 case 12:
3014
3015 return 6;
3016 case 8:
3017
3018 return 3;
3019 default:
3020 break;
3021 }
3022 break;
3023 case 1:
3024
3025 return 1;
3026 default:
3027 break;
3028 }
3029
3030 return 0;
3031}
3032
3033
3034
3035
3036
3037
3038
3039
3040
3041
3042
3043
3044
3045
3046
3047int scsi_vpd_lun_id(struct scsi_device *sdev, char *id, size_t id_len)
3048{
3049 u8 cur_id_prio = 0;
3050 u8 cur_id_size = 0;
3051 const unsigned char *d, *cur_id_str;
3052 const struct scsi_vpd *vpd_pg83;
3053 int id_size = -EINVAL;
3054
3055 rcu_read_lock();
3056 vpd_pg83 = rcu_dereference(sdev->vpd_pg83);
3057 if (!vpd_pg83) {
3058 rcu_read_unlock();
3059 return -ENXIO;
3060 }
3061
3062
3063 if (id_len < 21) {
3064 rcu_read_unlock();
3065 return -EINVAL;
3066 }
3067
3068 memset(id, 0, id_len);
3069 for (d = vpd_pg83->data + 4;
3070 d < vpd_pg83->data + vpd_pg83->len;
3071 d += d[3] + 4) {
3072 u8 prio = designator_prio(d);
3073
3074 if (prio == 0 || cur_id_prio > prio)
3075 continue;
3076
3077 switch (d[1] & 0xf) {
3078 case 0x1:
3079
3080 if (cur_id_size > d[3])
3081 break;
3082 cur_id_prio = prio;
3083 cur_id_size = d[3];
3084 if (cur_id_size + 4 > id_len)
3085 cur_id_size = id_len - 4;
3086 cur_id_str = d + 4;
3087 id_size = snprintf(id, id_len, "t10.%*pE",
3088 cur_id_size, cur_id_str);
3089 break;
3090 case 0x2:
3091
3092 cur_id_prio = prio;
3093 cur_id_size = d[3];
3094 cur_id_str = d + 4;
3095 switch (cur_id_size) {
3096 case 8:
3097 id_size = snprintf(id, id_len,
3098 "eui.%8phN",
3099 cur_id_str);
3100 break;
3101 case 12:
3102 id_size = snprintf(id, id_len,
3103 "eui.%12phN",
3104 cur_id_str);
3105 break;
3106 case 16:
3107 id_size = snprintf(id, id_len,
3108 "eui.%16phN",
3109 cur_id_str);
3110 break;
3111 default:
3112 break;
3113 }
3114 break;
3115 case 0x3:
3116
3117 cur_id_prio = prio;
3118 cur_id_size = d[3];
3119 cur_id_str = d + 4;
3120 switch (cur_id_size) {
3121 case 8:
3122 id_size = snprintf(id, id_len,
3123 "naa.%8phN",
3124 cur_id_str);
3125 break;
3126 case 16:
3127 id_size = snprintf(id, id_len,
3128 "naa.%16phN",
3129 cur_id_str);
3130 break;
3131 default:
3132 break;
3133 }
3134 break;
3135 case 0x8:
3136
3137 if (cur_id_size > d[3])
3138 break;
3139
3140 if (d[3] > id_len) {
3141 prio = 2;
3142 if (cur_id_prio > prio)
3143 break;
3144 }
3145 cur_id_prio = prio;
3146 cur_id_size = id_size = d[3];
3147 cur_id_str = d + 4;
3148 if (cur_id_size >= id_len)
3149 cur_id_size = id_len - 1;
3150 memcpy(id, cur_id_str, cur_id_size);
3151 break;
3152 default:
3153 break;
3154 }
3155 }
3156 rcu_read_unlock();
3157
3158 return id_size;
3159}
3160EXPORT_SYMBOL(scsi_vpd_lun_id);
3161
3162
3163
3164
3165
3166
3167
3168
3169
3170
3171int scsi_vpd_tpg_id(struct scsi_device *sdev, int *rel_id)
3172{
3173 const unsigned char *d;
3174 const struct scsi_vpd *vpd_pg83;
3175 int group_id = -EAGAIN, rel_port = -1;
3176
3177 rcu_read_lock();
3178 vpd_pg83 = rcu_dereference(sdev->vpd_pg83);
3179 if (!vpd_pg83) {
3180 rcu_read_unlock();
3181 return -ENXIO;
3182 }
3183
3184 d = vpd_pg83->data + 4;
3185 while (d < vpd_pg83->data + vpd_pg83->len) {
3186 switch (d[1] & 0xf) {
3187 case 0x4:
3188
3189 rel_port = get_unaligned_be16(&d[6]);
3190 break;
3191 case 0x5:
3192
3193 group_id = get_unaligned_be16(&d[6]);
3194 break;
3195 default:
3196 break;
3197 }
3198 d += d[3] + 4;
3199 }
3200 rcu_read_unlock();
3201
3202 if (group_id >= 0 && rel_id && rel_port != -1)
3203 *rel_id = rel_port;
3204
3205 return group_id;
3206}
3207EXPORT_SYMBOL(scsi_vpd_tpg_id);
3208
3209
3210
3211
3212
3213
3214
3215
3216
3217
3218
3219void scsi_build_sense(struct scsi_cmnd *scmd, int desc, u8 key, u8 asc, u8 ascq)
3220{
3221 scsi_build_sense_buffer(desc, scmd->sense_buffer, key, asc, ascq);
3222 scmd->result = SAM_STAT_CHECK_CONDITION;
3223}
3224EXPORT_SYMBOL_GPL(scsi_build_sense);
3225