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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 struct kmem_cache *scsi_sense_isadma_cache;
57static DEFINE_MUTEX(scsi_sense_cache_mutex);
58
59static void scsi_mq_uninit_cmd(struct scsi_cmnd *cmd);
60
61static inline struct kmem_cache *
62scsi_select_sense_cache(bool unchecked_isa_dma)
63{
64 return unchecked_isa_dma ? scsi_sense_isadma_cache : scsi_sense_cache;
65}
66
67static void scsi_free_sense_buffer(bool unchecked_isa_dma,
68 unsigned char *sense_buffer)
69{
70 kmem_cache_free(scsi_select_sense_cache(unchecked_isa_dma),
71 sense_buffer);
72}
73
74static unsigned char *scsi_alloc_sense_buffer(bool unchecked_isa_dma,
75 gfp_t gfp_mask, int numa_node)
76{
77 return kmem_cache_alloc_node(scsi_select_sense_cache(unchecked_isa_dma),
78 gfp_mask, numa_node);
79}
80
81int scsi_init_sense_cache(struct Scsi_Host *shost)
82{
83 struct kmem_cache *cache;
84 int ret = 0;
85
86 mutex_lock(&scsi_sense_cache_mutex);
87 cache = scsi_select_sense_cache(shost->unchecked_isa_dma);
88 if (cache)
89 goto exit;
90
91 if (shost->unchecked_isa_dma) {
92 scsi_sense_isadma_cache =
93 kmem_cache_create("scsi_sense_cache(DMA)",
94 SCSI_SENSE_BUFFERSIZE, 0,
95 SLAB_HWCACHE_ALIGN | SLAB_CACHE_DMA, NULL);
96 if (!scsi_sense_isadma_cache)
97 ret = -ENOMEM;
98 } else {
99 scsi_sense_cache =
100 kmem_cache_create_usercopy("scsi_sense_cache",
101 SCSI_SENSE_BUFFERSIZE, 0, SLAB_HWCACHE_ALIGN,
102 0, SCSI_SENSE_BUFFERSIZE, NULL);
103 if (!scsi_sense_cache)
104 ret = -ENOMEM;
105 }
106 exit:
107 mutex_unlock(&scsi_sense_cache_mutex);
108 return ret;
109}
110
111
112
113
114
115
116#define SCSI_QUEUE_DELAY 3
117
118static void
119scsi_set_blocked(struct scsi_cmnd *cmd, int reason)
120{
121 struct Scsi_Host *host = cmd->device->host;
122 struct scsi_device *device = cmd->device;
123 struct scsi_target *starget = scsi_target(device);
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138 switch (reason) {
139 case SCSI_MLQUEUE_HOST_BUSY:
140 atomic_set(&host->host_blocked, host->max_host_blocked);
141 break;
142 case SCSI_MLQUEUE_DEVICE_BUSY:
143 case SCSI_MLQUEUE_EH_RETRY:
144 atomic_set(&device->device_blocked,
145 device->max_device_blocked);
146 break;
147 case SCSI_MLQUEUE_TARGET_BUSY:
148 atomic_set(&starget->target_blocked,
149 starget->max_target_blocked);
150 break;
151 }
152}
153
154static void scsi_mq_requeue_cmd(struct scsi_cmnd *cmd)
155{
156 if (cmd->request->rq_flags & RQF_DONTPREP) {
157 cmd->request->rq_flags &= ~RQF_DONTPREP;
158 scsi_mq_uninit_cmd(cmd);
159 } else {
160 WARN_ON_ONCE(true);
161 }
162 blk_mq_requeue_request(cmd->request, true);
163}
164
165
166
167
168
169
170
171
172
173
174
175
176
177static void __scsi_queue_insert(struct scsi_cmnd *cmd, int reason, bool unbusy)
178{
179 struct scsi_device *device = cmd->device;
180
181 SCSI_LOG_MLQUEUE(1, scmd_printk(KERN_INFO, cmd,
182 "Inserting command %p into mlqueue\n", cmd));
183
184 scsi_set_blocked(cmd, reason);
185
186
187
188
189
190 if (unbusy)
191 scsi_device_unbusy(device, cmd);
192
193
194
195
196
197
198
199 cmd->result = 0;
200
201 blk_mq_requeue_request(cmd->request, true);
202}
203
204
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207
208
209
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211
212
213
214
215
216void scsi_queue_insert(struct scsi_cmnd *cmd, int reason)
217{
218 __scsi_queue_insert(cmd, reason, true);
219}
220
221
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238
239
240int __scsi_execute(struct scsi_device *sdev, const unsigned char *cmd,
241 int data_direction, void *buffer, unsigned bufflen,
242 unsigned char *sense, struct scsi_sense_hdr *sshdr,
243 int timeout, int retries, u64 flags, req_flags_t rq_flags,
244 int *resid)
245{
246 struct request *req;
247 struct scsi_request *rq;
248 int ret = DRIVER_ERROR << 24;
249
250 req = blk_get_request(sdev->request_queue,
251 data_direction == DMA_TO_DEVICE ?
252 REQ_OP_SCSI_OUT : REQ_OP_SCSI_IN, BLK_MQ_REQ_PREEMPT);
253 if (IS_ERR(req))
254 return ret;
255 rq = scsi_req(req);
256
257 if (bufflen && blk_rq_map_kern(sdev->request_queue, req,
258 buffer, bufflen, GFP_NOIO))
259 goto out;
260
261 rq->cmd_len = COMMAND_SIZE(cmd[0]);
262 memcpy(rq->cmd, cmd, rq->cmd_len);
263 rq->retries = retries;
264 req->timeout = timeout;
265 req->cmd_flags |= flags;
266 req->rq_flags |= rq_flags | RQF_QUIET;
267
268
269
270
271 blk_execute_rq(req->q, NULL, req, 1);
272
273
274
275
276
277
278
279 if (unlikely(rq->resid_len > 0 && rq->resid_len <= bufflen))
280 memset(buffer + (bufflen - rq->resid_len), 0, rq->resid_len);
281
282 if (resid)
283 *resid = rq->resid_len;
284 if (sense && rq->sense_len)
285 memcpy(sense, rq->sense, SCSI_SENSE_BUFFERSIZE);
286 if (sshdr)
287 scsi_normalize_sense(rq->sense, rq->sense_len, sshdr);
288 ret = rq->result;
289 out:
290 blk_put_request(req);
291
292 return ret;
293}
294EXPORT_SYMBOL(__scsi_execute);
295
296
297
298
299
300
301
302
303static void scsi_init_cmd_errh(struct scsi_cmnd *cmd)
304{
305 scsi_set_resid(cmd, 0);
306 memset(cmd->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE);
307 if (cmd->cmd_len == 0)
308 cmd->cmd_len = scsi_command_size(cmd->cmnd);
309}
310
311
312
313
314
315
316
317
318
319
320static void scsi_dec_host_busy(struct Scsi_Host *shost, struct scsi_cmnd *cmd)
321{
322 unsigned long flags;
323
324 rcu_read_lock();
325 __clear_bit(SCMD_STATE_INFLIGHT, &cmd->state);
326 if (unlikely(scsi_host_in_recovery(shost))) {
327 spin_lock_irqsave(shost->host_lock, flags);
328 if (shost->host_failed || shost->host_eh_scheduled)
329 scsi_eh_wakeup(shost);
330 spin_unlock_irqrestore(shost->host_lock, flags);
331 }
332 rcu_read_unlock();
333}
334
335void scsi_device_unbusy(struct scsi_device *sdev, struct scsi_cmnd *cmd)
336{
337 struct Scsi_Host *shost = sdev->host;
338 struct scsi_target *starget = scsi_target(sdev);
339
340 scsi_dec_host_busy(shost, cmd);
341
342 if (starget->can_queue > 0)
343 atomic_dec(&starget->target_busy);
344
345 atomic_dec(&sdev->device_busy);
346}
347
348static void scsi_kick_queue(struct request_queue *q)
349{
350 blk_mq_run_hw_queues(q, false);
351}
352
353
354
355
356
357
358
359
360static void scsi_single_lun_run(struct scsi_device *current_sdev)
361{
362 struct Scsi_Host *shost = current_sdev->host;
363 struct scsi_device *sdev, *tmp;
364 struct scsi_target *starget = scsi_target(current_sdev);
365 unsigned long flags;
366
367 spin_lock_irqsave(shost->host_lock, flags);
368 starget->starget_sdev_user = NULL;
369 spin_unlock_irqrestore(shost->host_lock, flags);
370
371
372
373
374
375
376
377 scsi_kick_queue(current_sdev->request_queue);
378
379 spin_lock_irqsave(shost->host_lock, flags);
380 if (starget->starget_sdev_user)
381 goto out;
382 list_for_each_entry_safe(sdev, tmp, &starget->devices,
383 same_target_siblings) {
384 if (sdev == current_sdev)
385 continue;
386 if (scsi_device_get(sdev))
387 continue;
388
389 spin_unlock_irqrestore(shost->host_lock, flags);
390 scsi_kick_queue(sdev->request_queue);
391 spin_lock_irqsave(shost->host_lock, flags);
392
393 scsi_device_put(sdev);
394 }
395 out:
396 spin_unlock_irqrestore(shost->host_lock, flags);
397}
398
399static inline bool scsi_device_is_busy(struct scsi_device *sdev)
400{
401 if (atomic_read(&sdev->device_busy) >= sdev->queue_depth)
402 return true;
403 if (atomic_read(&sdev->device_blocked) > 0)
404 return true;
405 return false;
406}
407
408static inline bool scsi_target_is_busy(struct scsi_target *starget)
409{
410 if (starget->can_queue > 0) {
411 if (atomic_read(&starget->target_busy) >= starget->can_queue)
412 return true;
413 if (atomic_read(&starget->target_blocked) > 0)
414 return true;
415 }
416 return false;
417}
418
419static inline bool scsi_host_is_busy(struct Scsi_Host *shost)
420{
421 if (atomic_read(&shost->host_blocked) > 0)
422 return true;
423 if (shost->host_self_blocked)
424 return true;
425 return false;
426}
427
428static void scsi_starved_list_run(struct Scsi_Host *shost)
429{
430 LIST_HEAD(starved_list);
431 struct scsi_device *sdev;
432 unsigned long flags;
433
434 spin_lock_irqsave(shost->host_lock, flags);
435 list_splice_init(&shost->starved_list, &starved_list);
436
437 while (!list_empty(&starved_list)) {
438 struct request_queue *slq;
439
440
441
442
443
444
445
446
447
448
449
450 if (scsi_host_is_busy(shost))
451 break;
452
453 sdev = list_entry(starved_list.next,
454 struct scsi_device, starved_entry);
455 list_del_init(&sdev->starved_entry);
456 if (scsi_target_is_busy(scsi_target(sdev))) {
457 list_move_tail(&sdev->starved_entry,
458 &shost->starved_list);
459 continue;
460 }
461
462
463
464
465
466
467
468
469
470
471
472 slq = sdev->request_queue;
473 if (!blk_get_queue(slq))
474 continue;
475 spin_unlock_irqrestore(shost->host_lock, flags);
476
477 scsi_kick_queue(slq);
478 blk_put_queue(slq);
479
480 spin_lock_irqsave(shost->host_lock, flags);
481 }
482
483 list_splice(&starved_list, &shost->starved_list);
484 spin_unlock_irqrestore(shost->host_lock, flags);
485}
486
487
488
489
490
491
492
493static void scsi_run_queue(struct request_queue *q)
494{
495 struct scsi_device *sdev = q->queuedata;
496
497 if (scsi_target(sdev)->single_lun)
498 scsi_single_lun_run(sdev);
499 if (!list_empty(&sdev->host->starved_list))
500 scsi_starved_list_run(sdev->host);
501
502 blk_mq_run_hw_queues(q, false);
503}
504
505void scsi_requeue_run_queue(struct work_struct *work)
506{
507 struct scsi_device *sdev;
508 struct request_queue *q;
509
510 sdev = container_of(work, struct scsi_device, requeue_work);
511 q = sdev->request_queue;
512 scsi_run_queue(q);
513}
514
515void scsi_run_host_queues(struct Scsi_Host *shost)
516{
517 struct scsi_device *sdev;
518
519 shost_for_each_device(sdev, shost)
520 scsi_run_queue(sdev->request_queue);
521}
522
523static void scsi_uninit_cmd(struct scsi_cmnd *cmd)
524{
525 if (!blk_rq_is_passthrough(cmd->request)) {
526 struct scsi_driver *drv = scsi_cmd_to_driver(cmd);
527
528 if (drv->uninit_command)
529 drv->uninit_command(cmd);
530 }
531}
532
533static void scsi_free_sgtables(struct scsi_cmnd *cmd)
534{
535 if (cmd->sdb.table.nents)
536 sg_free_table_chained(&cmd->sdb.table,
537 SCSI_INLINE_SG_CNT);
538 if (scsi_prot_sg_count(cmd))
539 sg_free_table_chained(&cmd->prot_sdb->table,
540 SCSI_INLINE_PROT_SG_CNT);
541}
542
543static void scsi_mq_uninit_cmd(struct scsi_cmnd *cmd)
544{
545 scsi_free_sgtables(cmd);
546 scsi_uninit_cmd(cmd);
547}
548
549static void scsi_run_queue_async(struct scsi_device *sdev)
550{
551 if (scsi_target(sdev)->single_lun ||
552 !list_empty(&sdev->host->starved_list))
553 kblockd_schedule_work(&sdev->requeue_work);
554 else
555 blk_mq_run_hw_queues(sdev->request_queue, true);
556}
557
558
559static bool scsi_end_request(struct request *req, blk_status_t error,
560 unsigned int bytes)
561{
562 struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req);
563 struct scsi_device *sdev = cmd->device;
564 struct request_queue *q = sdev->request_queue;
565
566 if (blk_update_request(req, error, bytes))
567 return true;
568
569 if (blk_queue_add_random(q))
570 add_disk_randomness(req->rq_disk);
571
572 if (!blk_rq_is_scsi(req)) {
573 WARN_ON_ONCE(!(cmd->flags & SCMD_INITIALIZED));
574 cmd->flags &= ~SCMD_INITIALIZED;
575 }
576
577
578
579
580
581
582
583 destroy_rcu_head(&cmd->rcu);
584
585
586
587
588
589
590
591
592 scsi_mq_uninit_cmd(cmd);
593
594
595
596
597
598 percpu_ref_get(&q->q_usage_counter);
599
600 __blk_mq_end_request(req, error);
601
602 scsi_run_queue_async(sdev);
603
604 percpu_ref_put(&q->q_usage_counter);
605 return false;
606}
607
608
609
610
611
612
613
614
615
616static blk_status_t scsi_result_to_blk_status(struct scsi_cmnd *cmd, int result)
617{
618 switch (host_byte(result)) {
619 case DID_OK:
620
621
622
623
624
625 if (scsi_status_is_good(result) && (result & ~0xff) == 0)
626 return BLK_STS_OK;
627 return BLK_STS_IOERR;
628 case DID_TRANSPORT_FAILFAST:
629 return BLK_STS_TRANSPORT;
630 case DID_TARGET_FAILURE:
631 set_host_byte(cmd, DID_OK);
632 return BLK_STS_TARGET;
633 case DID_NEXUS_FAILURE:
634 set_host_byte(cmd, DID_OK);
635 return BLK_STS_NEXUS;
636 case DID_ALLOC_FAILURE:
637 set_host_byte(cmd, DID_OK);
638 return BLK_STS_NOSPC;
639 case DID_MEDIUM_ERROR:
640 set_host_byte(cmd, DID_OK);
641 return BLK_STS_MEDIUM;
642 default:
643 return BLK_STS_IOERR;
644 }
645}
646
647
648static void scsi_io_completion_reprep(struct scsi_cmnd *cmd,
649 struct request_queue *q)
650{
651
652 scsi_mq_requeue_cmd(cmd);
653}
654
655
656static void scsi_io_completion_action(struct scsi_cmnd *cmd, int result)
657{
658 struct request_queue *q = cmd->device->request_queue;
659 struct request *req = cmd->request;
660 int level = 0;
661 enum {ACTION_FAIL, ACTION_REPREP, ACTION_RETRY,
662 ACTION_DELAYED_RETRY} action;
663 unsigned long wait_for = (cmd->allowed + 1) * req->timeout;
664 struct scsi_sense_hdr sshdr;
665 bool sense_valid;
666 bool sense_current = true;
667 blk_status_t blk_stat;
668
669 sense_valid = scsi_command_normalize_sense(cmd, &sshdr);
670 if (sense_valid)
671 sense_current = !scsi_sense_is_deferred(&sshdr);
672
673 blk_stat = scsi_result_to_blk_status(cmd, result);
674
675 if (host_byte(result) == DID_RESET) {
676
677
678
679
680 action = ACTION_RETRY;
681 } else if (sense_valid && sense_current) {
682 switch (sshdr.sense_key) {
683 case UNIT_ATTENTION:
684 if (cmd->device->removable) {
685
686
687
688 cmd->device->changed = 1;
689 action = ACTION_FAIL;
690 } else {
691
692
693
694
695
696 action = ACTION_RETRY;
697 }
698 break;
699 case ILLEGAL_REQUEST:
700
701
702
703
704
705
706
707
708 if ((cmd->device->use_10_for_rw &&
709 sshdr.asc == 0x20 && sshdr.ascq == 0x00) &&
710 (cmd->cmnd[0] == READ_10 ||
711 cmd->cmnd[0] == WRITE_10)) {
712
713 cmd->device->use_10_for_rw = 0;
714 action = ACTION_REPREP;
715 } else if (sshdr.asc == 0x10) {
716 action = ACTION_FAIL;
717 blk_stat = BLK_STS_PROTECTION;
718
719 } else if (sshdr.asc == 0x20 || sshdr.asc == 0x24) {
720 action = ACTION_FAIL;
721 blk_stat = BLK_STS_TARGET;
722 } else
723 action = ACTION_FAIL;
724 break;
725 case ABORTED_COMMAND:
726 action = ACTION_FAIL;
727 if (sshdr.asc == 0x10)
728 blk_stat = BLK_STS_PROTECTION;
729 break;
730 case NOT_READY:
731
732
733
734 if (sshdr.asc == 0x04) {
735 switch (sshdr.ascq) {
736 case 0x01:
737 case 0x04:
738 case 0x05:
739 case 0x06:
740 case 0x07:
741 case 0x08:
742 case 0x09:
743 case 0x14:
744 case 0x1a:
745 case 0x1b:
746 case 0x1d:
747 case 0x24:
748 action = ACTION_DELAYED_RETRY;
749 break;
750 default:
751 action = ACTION_FAIL;
752 break;
753 }
754 } else
755 action = ACTION_FAIL;
756 break;
757 case VOLUME_OVERFLOW:
758
759 action = ACTION_FAIL;
760 break;
761 default:
762 action = ACTION_FAIL;
763 break;
764 }
765 } else
766 action = ACTION_FAIL;
767
768 if (action != ACTION_FAIL &&
769 time_before(cmd->jiffies_at_alloc + wait_for, jiffies))
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 (driver_byte(result) == DRIVER_SENSE)
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 = cmd->request;
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 (status_byte(result) && 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 = cmd->request;
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
977blk_status_t scsi_init_io(struct scsi_cmnd *cmd)
978{
979 struct scsi_device *sdev = cmd->device;
980 struct request *rq = cmd->request;
981 unsigned short nr_segs = blk_rq_nr_phys_segments(rq);
982 struct scatterlist *last_sg = NULL;
983 blk_status_t ret;
984 bool need_drain = scsi_cmd_needs_dma_drain(sdev, rq);
985 int count;
986
987 if (WARN_ON_ONCE(!nr_segs))
988 return BLK_STS_IOERR;
989
990
991
992
993
994 if (need_drain)
995 nr_segs++;
996
997
998
999
1000 if (unlikely(sg_alloc_table_chained(&cmd->sdb.table, nr_segs,
1001 cmd->sdb.table.sgl, SCSI_INLINE_SG_CNT)))
1002 return BLK_STS_RESOURCE;
1003
1004
1005
1006
1007
1008 count = __blk_rq_map_sg(rq->q, rq, cmd->sdb.table.sgl, &last_sg);
1009
1010 if (blk_rq_bytes(rq) & rq->q->dma_pad_mask) {
1011 unsigned int pad_len =
1012 (rq->q->dma_pad_mask & ~blk_rq_bytes(rq)) + 1;
1013
1014 last_sg->length += pad_len;
1015 cmd->extra_len += pad_len;
1016 }
1017
1018 if (need_drain) {
1019 sg_unmark_end(last_sg);
1020 last_sg = sg_next(last_sg);
1021 sg_set_buf(last_sg, sdev->dma_drain_buf, sdev->dma_drain_len);
1022 sg_mark_end(last_sg);
1023
1024 cmd->extra_len += sdev->dma_drain_len;
1025 count++;
1026 }
1027
1028 BUG_ON(count > cmd->sdb.table.nents);
1029 cmd->sdb.table.nents = count;
1030 cmd->sdb.length = blk_rq_payload_bytes(rq);
1031
1032 if (blk_integrity_rq(rq)) {
1033 struct scsi_data_buffer *prot_sdb = cmd->prot_sdb;
1034 int ivecs;
1035
1036 if (WARN_ON_ONCE(!prot_sdb)) {
1037
1038
1039
1040
1041
1042 ret = BLK_STS_IOERR;
1043 goto out_free_sgtables;
1044 }
1045
1046 ivecs = blk_rq_count_integrity_sg(rq->q, rq->bio);
1047
1048 if (sg_alloc_table_chained(&prot_sdb->table, ivecs,
1049 prot_sdb->table.sgl,
1050 SCSI_INLINE_PROT_SG_CNT)) {
1051 ret = BLK_STS_RESOURCE;
1052 goto out_free_sgtables;
1053 }
1054
1055 count = blk_rq_map_integrity_sg(rq->q, rq->bio,
1056 prot_sdb->table.sgl);
1057 BUG_ON(count > ivecs);
1058 BUG_ON(count > queue_max_integrity_segments(rq->q));
1059
1060 cmd->prot_sdb = prot_sdb;
1061 cmd->prot_sdb->table.nents = count;
1062 }
1063
1064 return BLK_STS_OK;
1065out_free_sgtables:
1066 scsi_free_sgtables(cmd);
1067 return ret;
1068}
1069EXPORT_SYMBOL(scsi_init_io);
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082static void scsi_initialize_rq(struct request *rq)
1083{
1084 struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq);
1085
1086 scsi_req_init(&cmd->req);
1087 init_rcu_head(&cmd->rcu);
1088 cmd->jiffies_at_alloc = jiffies;
1089 cmd->retries = 0;
1090}
1091
1092
1093
1094
1095
1096static void scsi_cleanup_rq(struct request *rq)
1097{
1098 if (rq->rq_flags & RQF_DONTPREP) {
1099 scsi_mq_uninit_cmd(blk_mq_rq_to_pdu(rq));
1100 rq->rq_flags &= ~RQF_DONTPREP;
1101 }
1102}
1103
1104
1105void scsi_init_command(struct scsi_device *dev, struct scsi_cmnd *cmd)
1106{
1107 void *buf = cmd->sense_buffer;
1108 void *prot = cmd->prot_sdb;
1109 struct request *rq = blk_mq_rq_from_pdu(cmd);
1110 unsigned int flags = cmd->flags & SCMD_PRESERVED_FLAGS;
1111 unsigned long jiffies_at_alloc;
1112 int retries, to_clear;
1113 bool in_flight;
1114
1115 if (!blk_rq_is_scsi(rq) && !(flags & SCMD_INITIALIZED)) {
1116 flags |= SCMD_INITIALIZED;
1117 scsi_initialize_rq(rq);
1118 }
1119
1120 jiffies_at_alloc = cmd->jiffies_at_alloc;
1121 retries = cmd->retries;
1122 in_flight = test_bit(SCMD_STATE_INFLIGHT, &cmd->state);
1123
1124
1125
1126
1127
1128 to_clear = sizeof(*cmd) - sizeof(cmd->req);
1129 if (!dev->host->hostt->init_cmd_priv)
1130 to_clear += dev->host->hostt->cmd_size;
1131 memset((char *)cmd + sizeof(cmd->req), 0, to_clear);
1132
1133 cmd->device = dev;
1134 cmd->sense_buffer = buf;
1135 cmd->prot_sdb = prot;
1136 cmd->flags = flags;
1137 INIT_DELAYED_WORK(&cmd->abort_work, scmd_eh_abort_handler);
1138 cmd->jiffies_at_alloc = jiffies_at_alloc;
1139 cmd->retries = retries;
1140 if (in_flight)
1141 __set_bit(SCMD_STATE_INFLIGHT, &cmd->state);
1142
1143}
1144
1145static blk_status_t scsi_setup_scsi_cmnd(struct scsi_device *sdev,
1146 struct request *req)
1147{
1148 struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req);
1149
1150
1151
1152
1153
1154
1155
1156 if (req->bio) {
1157 blk_status_t ret = scsi_init_io(cmd);
1158 if (unlikely(ret != BLK_STS_OK))
1159 return ret;
1160 } else {
1161 BUG_ON(blk_rq_bytes(req));
1162
1163 memset(&cmd->sdb, 0, sizeof(cmd->sdb));
1164 }
1165
1166 cmd->cmd_len = scsi_req(req)->cmd_len;
1167 cmd->cmnd = scsi_req(req)->cmd;
1168 cmd->transfersize = blk_rq_bytes(req);
1169 cmd->allowed = scsi_req(req)->retries;
1170 return BLK_STS_OK;
1171}
1172
1173
1174
1175
1176
1177static blk_status_t scsi_setup_fs_cmnd(struct scsi_device *sdev,
1178 struct request *req)
1179{
1180 struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req);
1181
1182 if (unlikely(sdev->handler && sdev->handler->prep_fn)) {
1183 blk_status_t ret = sdev->handler->prep_fn(sdev, req);
1184 if (ret != BLK_STS_OK)
1185 return ret;
1186 }
1187
1188 cmd->cmnd = scsi_req(req)->cmd = scsi_req(req)->__cmd;
1189 memset(cmd->cmnd, 0, BLK_MAX_CDB);
1190 return scsi_cmd_to_driver(cmd)->init_command(cmd);
1191}
1192
1193static blk_status_t scsi_setup_cmnd(struct scsi_device *sdev,
1194 struct request *req)
1195{
1196 struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req);
1197 blk_status_t ret;
1198
1199 if (!blk_rq_bytes(req))
1200 cmd->sc_data_direction = DMA_NONE;
1201 else if (rq_data_dir(req) == WRITE)
1202 cmd->sc_data_direction = DMA_TO_DEVICE;
1203 else
1204 cmd->sc_data_direction = DMA_FROM_DEVICE;
1205
1206 if (blk_rq_is_scsi(req))
1207 ret = scsi_setup_scsi_cmnd(sdev, req);
1208 else
1209 ret = scsi_setup_fs_cmnd(sdev, req);
1210
1211 if (ret != BLK_STS_OK)
1212 scsi_free_sgtables(cmd);
1213
1214 return ret;
1215}
1216
1217static blk_status_t
1218scsi_prep_state_check(struct scsi_device *sdev, struct request *req)
1219{
1220 switch (sdev->sdev_state) {
1221 case SDEV_OFFLINE:
1222 case SDEV_TRANSPORT_OFFLINE:
1223
1224
1225
1226
1227
1228 if (!sdev->offline_already) {
1229 sdev->offline_already = true;
1230 sdev_printk(KERN_ERR, sdev,
1231 "rejecting I/O to offline device\n");
1232 }
1233 return BLK_STS_IOERR;
1234 case SDEV_DEL:
1235
1236
1237
1238
1239 sdev_printk(KERN_ERR, sdev,
1240 "rejecting I/O to dead device\n");
1241 return BLK_STS_IOERR;
1242 case SDEV_BLOCK:
1243 case SDEV_CREATED_BLOCK:
1244 return BLK_STS_RESOURCE;
1245 case SDEV_QUIESCE:
1246
1247
1248
1249 if (req && !(req->rq_flags & RQF_PREEMPT))
1250 return BLK_STS_RESOURCE;
1251 return BLK_STS_OK;
1252 default:
1253
1254
1255
1256
1257
1258 if (req && !(req->rq_flags & RQF_PREEMPT))
1259 return BLK_STS_IOERR;
1260 return BLK_STS_OK;
1261 }
1262}
1263
1264
1265
1266
1267
1268
1269
1270static inline int scsi_dev_queue_ready(struct request_queue *q,
1271 struct scsi_device *sdev)
1272{
1273 unsigned int busy;
1274
1275 busy = atomic_inc_return(&sdev->device_busy) - 1;
1276 if (atomic_read(&sdev->device_blocked)) {
1277 if (busy)
1278 goto out_dec;
1279
1280
1281
1282
1283 if (atomic_dec_return(&sdev->device_blocked) > 0)
1284 goto out_dec;
1285 SCSI_LOG_MLQUEUE(3, sdev_printk(KERN_INFO, sdev,
1286 "unblocking device at zero depth\n"));
1287 }
1288
1289 if (busy >= sdev->queue_depth)
1290 goto out_dec;
1291
1292 return 1;
1293out_dec:
1294 atomic_dec(&sdev->device_busy);
1295 return 0;
1296}
1297
1298
1299
1300
1301
1302static inline int scsi_target_queue_ready(struct Scsi_Host *shost,
1303 struct scsi_device *sdev)
1304{
1305 struct scsi_target *starget = scsi_target(sdev);
1306 unsigned int busy;
1307
1308 if (starget->single_lun) {
1309 spin_lock_irq(shost->host_lock);
1310 if (starget->starget_sdev_user &&
1311 starget->starget_sdev_user != sdev) {
1312 spin_unlock_irq(shost->host_lock);
1313 return 0;
1314 }
1315 starget->starget_sdev_user = sdev;
1316 spin_unlock_irq(shost->host_lock);
1317 }
1318
1319 if (starget->can_queue <= 0)
1320 return 1;
1321
1322 busy = atomic_inc_return(&starget->target_busy) - 1;
1323 if (atomic_read(&starget->target_blocked) > 0) {
1324 if (busy)
1325 goto starved;
1326
1327
1328
1329
1330 if (atomic_dec_return(&starget->target_blocked) > 0)
1331 goto out_dec;
1332
1333 SCSI_LOG_MLQUEUE(3, starget_printk(KERN_INFO, starget,
1334 "unblocking target at zero depth\n"));
1335 }
1336
1337 if (busy >= starget->can_queue)
1338 goto starved;
1339
1340 return 1;
1341
1342starved:
1343 spin_lock_irq(shost->host_lock);
1344 list_move_tail(&sdev->starved_entry, &shost->starved_list);
1345 spin_unlock_irq(shost->host_lock);
1346out_dec:
1347 if (starget->can_queue > 0)
1348 atomic_dec(&starget->target_busy);
1349 return 0;
1350}
1351
1352
1353
1354
1355
1356
1357static inline int scsi_host_queue_ready(struct request_queue *q,
1358 struct Scsi_Host *shost,
1359 struct scsi_device *sdev,
1360 struct scsi_cmnd *cmd)
1361{
1362 if (scsi_host_in_recovery(shost))
1363 return 0;
1364
1365 if (atomic_read(&shost->host_blocked) > 0) {
1366 if (scsi_host_busy(shost) > 0)
1367 goto starved;
1368
1369
1370
1371
1372 if (atomic_dec_return(&shost->host_blocked) > 0)
1373 goto out_dec;
1374
1375 SCSI_LOG_MLQUEUE(3,
1376 shost_printk(KERN_INFO, shost,
1377 "unblocking host at zero depth\n"));
1378 }
1379
1380 if (shost->host_self_blocked)
1381 goto starved;
1382
1383
1384 if (!list_empty(&sdev->starved_entry)) {
1385 spin_lock_irq(shost->host_lock);
1386 if (!list_empty(&sdev->starved_entry))
1387 list_del_init(&sdev->starved_entry);
1388 spin_unlock_irq(shost->host_lock);
1389 }
1390
1391 __set_bit(SCMD_STATE_INFLIGHT, &cmd->state);
1392
1393 return 1;
1394
1395starved:
1396 spin_lock_irq(shost->host_lock);
1397 if (list_empty(&sdev->starved_entry))
1398 list_add_tail(&sdev->starved_entry, &shost->starved_list);
1399 spin_unlock_irq(shost->host_lock);
1400out_dec:
1401 scsi_dec_host_busy(shost, cmd);
1402 return 0;
1403}
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417static bool scsi_mq_lld_busy(struct request_queue *q)
1418{
1419 struct scsi_device *sdev = q->queuedata;
1420 struct Scsi_Host *shost;
1421
1422 if (blk_queue_dying(q))
1423 return false;
1424
1425 shost = sdev->host;
1426
1427
1428
1429
1430
1431
1432
1433 if (scsi_host_in_recovery(shost) || scsi_device_is_busy(sdev))
1434 return true;
1435
1436 return false;
1437}
1438
1439static void scsi_softirq_done(struct request *rq)
1440{
1441 struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq);
1442 unsigned long wait_for = (cmd->allowed + 1) * rq->timeout;
1443 int disposition;
1444
1445 INIT_LIST_HEAD(&cmd->eh_entry);
1446
1447 atomic_inc(&cmd->device->iodone_cnt);
1448 if (cmd->result)
1449 atomic_inc(&cmd->device->ioerr_cnt);
1450
1451 disposition = scsi_decide_disposition(cmd);
1452 if (disposition != SUCCESS &&
1453 time_before(cmd->jiffies_at_alloc + wait_for, jiffies)) {
1454 scmd_printk(KERN_ERR, cmd,
1455 "timing out command, waited %lus\n",
1456 wait_for/HZ);
1457 disposition = SUCCESS;
1458 }
1459
1460 scsi_log_completion(cmd, disposition);
1461
1462 switch (disposition) {
1463 case SUCCESS:
1464 scsi_finish_command(cmd);
1465 break;
1466 case NEEDS_RETRY:
1467 scsi_queue_insert(cmd, SCSI_MLQUEUE_EH_RETRY);
1468 break;
1469 case ADD_TO_MLQUEUE:
1470 scsi_queue_insert(cmd, SCSI_MLQUEUE_DEVICE_BUSY);
1471 break;
1472 default:
1473 scsi_eh_scmd_add(cmd);
1474 break;
1475 }
1476}
1477
1478
1479
1480
1481
1482
1483
1484
1485static int scsi_dispatch_cmd(struct scsi_cmnd *cmd)
1486{
1487 struct Scsi_Host *host = cmd->device->host;
1488 int rtn = 0;
1489
1490 atomic_inc(&cmd->device->iorequest_cnt);
1491
1492
1493 if (unlikely(cmd->device->sdev_state == SDEV_DEL)) {
1494
1495
1496
1497 cmd->result = DID_NO_CONNECT << 16;
1498 goto done;
1499 }
1500
1501
1502 if (unlikely(scsi_device_blocked(cmd->device))) {
1503
1504
1505
1506
1507
1508
1509
1510 SCSI_LOG_MLQUEUE(3, scmd_printk(KERN_INFO, cmd,
1511 "queuecommand : device blocked\n"));
1512 return SCSI_MLQUEUE_DEVICE_BUSY;
1513 }
1514
1515
1516 if (cmd->device->lun_in_cdb)
1517 cmd->cmnd[1] = (cmd->cmnd[1] & 0x1f) |
1518 (cmd->device->lun << 5 & 0xe0);
1519
1520 scsi_log_send(cmd);
1521
1522
1523
1524
1525
1526 if (cmd->cmd_len > cmd->device->host->max_cmd_len) {
1527 SCSI_LOG_MLQUEUE(3, scmd_printk(KERN_INFO, cmd,
1528 "queuecommand : command too long. "
1529 "cdb_size=%d host->max_cmd_len=%d\n",
1530 cmd->cmd_len, cmd->device->host->max_cmd_len));
1531 cmd->result = (DID_ABORT << 16);
1532 goto done;
1533 }
1534
1535 if (unlikely(host->shost_state == SHOST_DEL)) {
1536 cmd->result = (DID_NO_CONNECT << 16);
1537 goto done;
1538
1539 }
1540
1541 trace_scsi_dispatch_cmd_start(cmd);
1542 rtn = host->hostt->queuecommand(host, cmd);
1543 if (rtn) {
1544 trace_scsi_dispatch_cmd_error(cmd, rtn);
1545 if (rtn != SCSI_MLQUEUE_DEVICE_BUSY &&
1546 rtn != SCSI_MLQUEUE_TARGET_BUSY)
1547 rtn = SCSI_MLQUEUE_HOST_BUSY;
1548
1549 SCSI_LOG_MLQUEUE(3, scmd_printk(KERN_INFO, cmd,
1550 "queuecommand : request rejected\n"));
1551 }
1552
1553 return rtn;
1554 done:
1555 cmd->scsi_done(cmd);
1556 return 0;
1557}
1558
1559
1560static unsigned int scsi_mq_inline_sgl_size(struct Scsi_Host *shost)
1561{
1562 return min_t(unsigned int, shost->sg_tablesize, SCSI_INLINE_SG_CNT) *
1563 sizeof(struct scatterlist);
1564}
1565
1566static blk_status_t scsi_mq_prep_fn(struct request *req)
1567{
1568 struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req);
1569 struct scsi_device *sdev = req->q->queuedata;
1570 struct Scsi_Host *shost = sdev->host;
1571 struct scatterlist *sg;
1572
1573 scsi_init_command(sdev, cmd);
1574
1575 cmd->request = req;
1576 cmd->tag = req->tag;
1577 cmd->prot_op = SCSI_PROT_NORMAL;
1578
1579 sg = (void *)cmd + sizeof(struct scsi_cmnd) + shost->hostt->cmd_size;
1580 cmd->sdb.table.sgl = sg;
1581
1582 if (scsi_host_get_prot(shost)) {
1583 memset(cmd->prot_sdb, 0, sizeof(struct scsi_data_buffer));
1584
1585 cmd->prot_sdb->table.sgl =
1586 (struct scatterlist *)(cmd->prot_sdb + 1);
1587 }
1588
1589 blk_mq_start_request(req);
1590
1591 return scsi_setup_cmnd(sdev, req);
1592}
1593
1594static void scsi_mq_done(struct scsi_cmnd *cmd)
1595{
1596 if (unlikely(blk_should_fake_timeout(cmd->request->q)))
1597 return;
1598 if (unlikely(test_and_set_bit(SCMD_STATE_COMPLETE, &cmd->state)))
1599 return;
1600 trace_scsi_dispatch_cmd_done(cmd);
1601 blk_mq_complete_request(cmd->request);
1602}
1603
1604static void scsi_mq_put_budget(struct request_queue *q)
1605{
1606 struct scsi_device *sdev = q->queuedata;
1607
1608 atomic_dec(&sdev->device_busy);
1609}
1610
1611static bool scsi_mq_get_budget(struct request_queue *q)
1612{
1613 struct scsi_device *sdev = q->queuedata;
1614
1615 return scsi_dev_queue_ready(q, sdev);
1616}
1617
1618static blk_status_t scsi_queue_rq(struct blk_mq_hw_ctx *hctx,
1619 const struct blk_mq_queue_data *bd)
1620{
1621 struct request *req = bd->rq;
1622 struct request_queue *q = req->q;
1623 struct scsi_device *sdev = q->queuedata;
1624 struct Scsi_Host *shost = sdev->host;
1625 struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req);
1626 blk_status_t ret;
1627 int reason;
1628
1629
1630
1631
1632
1633 if (unlikely(sdev->sdev_state != SDEV_RUNNING)) {
1634 ret = scsi_prep_state_check(sdev, req);
1635 if (ret != BLK_STS_OK)
1636 goto out_put_budget;
1637 }
1638
1639 ret = BLK_STS_RESOURCE;
1640 if (!scsi_target_queue_ready(shost, sdev))
1641 goto out_put_budget;
1642 if (!scsi_host_queue_ready(q, shost, sdev, cmd))
1643 goto out_dec_target_busy;
1644
1645 if (!(req->rq_flags & RQF_DONTPREP)) {
1646 ret = scsi_mq_prep_fn(req);
1647 if (ret != BLK_STS_OK)
1648 goto out_dec_host_busy;
1649 req->rq_flags |= RQF_DONTPREP;
1650 } else {
1651 clear_bit(SCMD_STATE_COMPLETE, &cmd->state);
1652 blk_mq_start_request(req);
1653 }
1654
1655 cmd->flags &= SCMD_PRESERVED_FLAGS;
1656 if (sdev->simple_tags)
1657 cmd->flags |= SCMD_TAGGED;
1658 if (bd->last)
1659 cmd->flags |= SCMD_LAST;
1660
1661 scsi_init_cmd_errh(cmd);
1662 cmd->scsi_done = scsi_mq_done;
1663
1664 reason = scsi_dispatch_cmd(cmd);
1665 if (reason) {
1666 scsi_set_blocked(cmd, reason);
1667 ret = BLK_STS_RESOURCE;
1668 goto out_dec_host_busy;
1669 }
1670
1671 return BLK_STS_OK;
1672
1673out_dec_host_busy:
1674 scsi_dec_host_busy(shost, cmd);
1675out_dec_target_busy:
1676 if (scsi_target(sdev)->can_queue > 0)
1677 atomic_dec(&scsi_target(sdev)->target_busy);
1678out_put_budget:
1679 scsi_mq_put_budget(q);
1680 switch (ret) {
1681 case BLK_STS_OK:
1682 break;
1683 case BLK_STS_RESOURCE:
1684 case BLK_STS_ZONE_RESOURCE:
1685 if (atomic_read(&sdev->device_busy) ||
1686 scsi_device_blocked(sdev))
1687 ret = BLK_STS_DEV_RESOURCE;
1688 break;
1689 default:
1690 if (unlikely(!scsi_device_online(sdev)))
1691 scsi_req(req)->result = DID_NO_CONNECT << 16;
1692 else
1693 scsi_req(req)->result = DID_ERROR << 16;
1694
1695
1696
1697
1698
1699 if (req->rq_flags & RQF_DONTPREP)
1700 scsi_mq_uninit_cmd(cmd);
1701 scsi_run_queue_async(sdev);
1702 break;
1703 }
1704 return ret;
1705}
1706
1707static enum blk_eh_timer_return scsi_timeout(struct request *req,
1708 bool reserved)
1709{
1710 if (reserved)
1711 return BLK_EH_RESET_TIMER;
1712 return scsi_times_out(req);
1713}
1714
1715static int scsi_mq_init_request(struct blk_mq_tag_set *set, struct request *rq,
1716 unsigned int hctx_idx, unsigned int numa_node)
1717{
1718 struct Scsi_Host *shost = set->driver_data;
1719 const bool unchecked_isa_dma = shost->unchecked_isa_dma;
1720 struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq);
1721 struct scatterlist *sg;
1722 int ret = 0;
1723
1724 if (unchecked_isa_dma)
1725 cmd->flags |= SCMD_UNCHECKED_ISA_DMA;
1726 cmd->sense_buffer = scsi_alloc_sense_buffer(unchecked_isa_dma,
1727 GFP_KERNEL, numa_node);
1728 if (!cmd->sense_buffer)
1729 return -ENOMEM;
1730 cmd->req.sense = cmd->sense_buffer;
1731
1732 if (scsi_host_get_prot(shost)) {
1733 sg = (void *)cmd + sizeof(struct scsi_cmnd) +
1734 shost->hostt->cmd_size;
1735 cmd->prot_sdb = (void *)sg + scsi_mq_inline_sgl_size(shost);
1736 }
1737
1738 if (shost->hostt->init_cmd_priv) {
1739 ret = shost->hostt->init_cmd_priv(shost, cmd);
1740 if (ret < 0)
1741 scsi_free_sense_buffer(unchecked_isa_dma,
1742 cmd->sense_buffer);
1743 }
1744
1745 return ret;
1746}
1747
1748static void scsi_mq_exit_request(struct blk_mq_tag_set *set, struct request *rq,
1749 unsigned int hctx_idx)
1750{
1751 struct Scsi_Host *shost = set->driver_data;
1752 struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq);
1753
1754 if (shost->hostt->exit_cmd_priv)
1755 shost->hostt->exit_cmd_priv(shost, cmd);
1756 scsi_free_sense_buffer(cmd->flags & SCMD_UNCHECKED_ISA_DMA,
1757 cmd->sense_buffer);
1758}
1759
1760static int scsi_map_queues(struct blk_mq_tag_set *set)
1761{
1762 struct Scsi_Host *shost = container_of(set, struct Scsi_Host, tag_set);
1763
1764 if (shost->hostt->map_queues)
1765 return shost->hostt->map_queues(shost);
1766 return blk_mq_map_queues(&set->map[HCTX_TYPE_DEFAULT]);
1767}
1768
1769void __scsi_init_queue(struct Scsi_Host *shost, struct request_queue *q)
1770{
1771 struct device *dev = shost->dma_dev;
1772
1773
1774
1775
1776 blk_queue_max_segments(q, min_t(unsigned short, shost->sg_tablesize,
1777 SG_MAX_SEGMENTS));
1778
1779 if (scsi_host_prot_dma(shost)) {
1780 shost->sg_prot_tablesize =
1781 min_not_zero(shost->sg_prot_tablesize,
1782 (unsigned short)SCSI_MAX_PROT_SG_SEGMENTS);
1783 BUG_ON(shost->sg_prot_tablesize < shost->sg_tablesize);
1784 blk_queue_max_integrity_segments(q, shost->sg_prot_tablesize);
1785 }
1786
1787 if (dev->dma_mask) {
1788 shost->max_sectors = min_t(unsigned int, shost->max_sectors,
1789 dma_max_mapping_size(dev) >> SECTOR_SHIFT);
1790 }
1791 blk_queue_max_hw_sectors(q, shost->max_sectors);
1792 if (shost->unchecked_isa_dma)
1793 blk_queue_bounce_limit(q, BLK_BOUNCE_ISA);
1794 blk_queue_segment_boundary(q, shost->dma_boundary);
1795 dma_set_seg_boundary(dev, shost->dma_boundary);
1796
1797 blk_queue_max_segment_size(q, shost->max_segment_size);
1798 blk_queue_virt_boundary(q, shost->virt_boundary_mask);
1799 dma_set_max_seg_size(dev, queue_max_segment_size(q));
1800
1801
1802
1803
1804
1805
1806
1807
1808 blk_queue_dma_alignment(q, max(4, dma_get_cache_alignment()) - 1);
1809}
1810EXPORT_SYMBOL_GPL(__scsi_init_queue);
1811
1812static const struct blk_mq_ops scsi_mq_ops_no_commit = {
1813 .get_budget = scsi_mq_get_budget,
1814 .put_budget = scsi_mq_put_budget,
1815 .queue_rq = scsi_queue_rq,
1816 .complete = scsi_softirq_done,
1817 .timeout = scsi_timeout,
1818#ifdef CONFIG_BLK_DEBUG_FS
1819 .show_rq = scsi_show_rq,
1820#endif
1821 .init_request = scsi_mq_init_request,
1822 .exit_request = scsi_mq_exit_request,
1823 .initialize_rq_fn = scsi_initialize_rq,
1824 .cleanup_rq = scsi_cleanup_rq,
1825 .busy = scsi_mq_lld_busy,
1826 .map_queues = scsi_map_queues,
1827};
1828
1829
1830static void scsi_commit_rqs(struct blk_mq_hw_ctx *hctx)
1831{
1832 struct request_queue *q = hctx->queue;
1833 struct scsi_device *sdev = q->queuedata;
1834 struct Scsi_Host *shost = sdev->host;
1835
1836 shost->hostt->commit_rqs(shost, hctx->queue_num);
1837}
1838
1839static const struct blk_mq_ops scsi_mq_ops = {
1840 .get_budget = scsi_mq_get_budget,
1841 .put_budget = scsi_mq_put_budget,
1842 .queue_rq = scsi_queue_rq,
1843 .commit_rqs = scsi_commit_rqs,
1844 .complete = scsi_softirq_done,
1845 .timeout = scsi_timeout,
1846#ifdef CONFIG_BLK_DEBUG_FS
1847 .show_rq = scsi_show_rq,
1848#endif
1849 .init_request = scsi_mq_init_request,
1850 .exit_request = scsi_mq_exit_request,
1851 .initialize_rq_fn = scsi_initialize_rq,
1852 .cleanup_rq = scsi_cleanup_rq,
1853 .busy = scsi_mq_lld_busy,
1854 .map_queues = scsi_map_queues,
1855};
1856
1857struct request_queue *scsi_mq_alloc_queue(struct scsi_device *sdev)
1858{
1859 sdev->request_queue = blk_mq_init_queue(&sdev->host->tag_set);
1860 if (IS_ERR(sdev->request_queue))
1861 return NULL;
1862
1863 sdev->request_queue->queuedata = sdev;
1864 __scsi_init_queue(sdev->host, sdev->request_queue);
1865 blk_queue_flag_set(QUEUE_FLAG_SCSI_PASSTHROUGH, sdev->request_queue);
1866 return sdev->request_queue;
1867}
1868
1869int scsi_mq_setup_tags(struct Scsi_Host *shost)
1870{
1871 unsigned int cmd_size, sgl_size;
1872 struct blk_mq_tag_set *tag_set = &shost->tag_set;
1873
1874 sgl_size = max_t(unsigned int, sizeof(struct scatterlist),
1875 scsi_mq_inline_sgl_size(shost));
1876 cmd_size = sizeof(struct scsi_cmnd) + shost->hostt->cmd_size + sgl_size;
1877 if (scsi_host_get_prot(shost))
1878 cmd_size += sizeof(struct scsi_data_buffer) +
1879 sizeof(struct scatterlist) * SCSI_INLINE_PROT_SG_CNT;
1880
1881 memset(tag_set, 0, sizeof(*tag_set));
1882 if (shost->hostt->commit_rqs)
1883 tag_set->ops = &scsi_mq_ops;
1884 else
1885 tag_set->ops = &scsi_mq_ops_no_commit;
1886 tag_set->nr_hw_queues = shost->nr_hw_queues ? : 1;
1887 tag_set->queue_depth = shost->can_queue;
1888 tag_set->cmd_size = cmd_size;
1889 tag_set->numa_node = NUMA_NO_NODE;
1890 tag_set->flags = BLK_MQ_F_SHOULD_MERGE;
1891 tag_set->flags |=
1892 BLK_ALLOC_POLICY_TO_MQ_FLAG(shost->hostt->tag_alloc_policy);
1893 tag_set->driver_data = shost;
1894
1895 return blk_mq_alloc_tag_set(tag_set);
1896}
1897
1898void scsi_mq_destroy_tags(struct Scsi_Host *shost)
1899{
1900 blk_mq_free_tag_set(&shost->tag_set);
1901}
1902
1903
1904
1905
1906
1907
1908
1909
1910struct scsi_device *scsi_device_from_queue(struct request_queue *q)
1911{
1912 struct scsi_device *sdev = NULL;
1913
1914 if (q->mq_ops == &scsi_mq_ops_no_commit ||
1915 q->mq_ops == &scsi_mq_ops)
1916 sdev = q->queuedata;
1917 if (!sdev || !get_device(&sdev->sdev_gendev))
1918 sdev = NULL;
1919
1920 return sdev;
1921}
1922EXPORT_SYMBOL_GPL(scsi_device_from_queue);
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932void scsi_block_requests(struct Scsi_Host *shost)
1933{
1934 shost->host_self_blocked = 1;
1935}
1936EXPORT_SYMBOL(scsi_block_requests);
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948void scsi_unblock_requests(struct Scsi_Host *shost)
1949{
1950 shost->host_self_blocked = 0;
1951 scsi_run_host_queues(shost);
1952}
1953EXPORT_SYMBOL(scsi_unblock_requests);
1954
1955void scsi_exit_queue(void)
1956{
1957 kmem_cache_destroy(scsi_sense_cache);
1958 kmem_cache_destroy(scsi_sense_isadma_cache);
1959}
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979int
1980scsi_mode_select(struct scsi_device *sdev, int pf, int sp, int modepage,
1981 unsigned char *buffer, int len, int timeout, int retries,
1982 struct scsi_mode_data *data, struct scsi_sense_hdr *sshdr)
1983{
1984 unsigned char cmd[10];
1985 unsigned char *real_buffer;
1986 int ret;
1987
1988 memset(cmd, 0, sizeof(cmd));
1989 cmd[1] = (pf ? 0x10 : 0) | (sp ? 0x01 : 0);
1990
1991 if (sdev->use_10_for_ms) {
1992 if (len > 65535)
1993 return -EINVAL;
1994 real_buffer = kmalloc(8 + len, GFP_KERNEL);
1995 if (!real_buffer)
1996 return -ENOMEM;
1997 memcpy(real_buffer + 8, buffer, len);
1998 len += 8;
1999 real_buffer[0] = 0;
2000 real_buffer[1] = 0;
2001 real_buffer[2] = data->medium_type;
2002 real_buffer[3] = data->device_specific;
2003 real_buffer[4] = data->longlba ? 0x01 : 0;
2004 real_buffer[5] = 0;
2005 real_buffer[6] = data->block_descriptor_length >> 8;
2006 real_buffer[7] = data->block_descriptor_length;
2007
2008 cmd[0] = MODE_SELECT_10;
2009 cmd[7] = len >> 8;
2010 cmd[8] = len;
2011 } else {
2012 if (len > 255 || data->block_descriptor_length > 255 ||
2013 data->longlba)
2014 return -EINVAL;
2015
2016 real_buffer = kmalloc(4 + len, GFP_KERNEL);
2017 if (!real_buffer)
2018 return -ENOMEM;
2019 memcpy(real_buffer + 4, buffer, len);
2020 len += 4;
2021 real_buffer[0] = 0;
2022 real_buffer[1] = data->medium_type;
2023 real_buffer[2] = data->device_specific;
2024 real_buffer[3] = data->block_descriptor_length;
2025
2026 cmd[0] = MODE_SELECT;
2027 cmd[4] = len;
2028 }
2029
2030 ret = scsi_execute_req(sdev, cmd, DMA_TO_DEVICE, real_buffer, len,
2031 sshdr, timeout, retries, NULL);
2032 kfree(real_buffer);
2033 return ret;
2034}
2035EXPORT_SYMBOL_GPL(scsi_mode_select);
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054int
2055scsi_mode_sense(struct scsi_device *sdev, int dbd, int modepage,
2056 unsigned char *buffer, int len, int timeout, int retries,
2057 struct scsi_mode_data *data, struct scsi_sense_hdr *sshdr)
2058{
2059 unsigned char cmd[12];
2060 int use_10_for_ms;
2061 int header_length;
2062 int result, retry_count = retries;
2063 struct scsi_sense_hdr my_sshdr;
2064
2065 memset(data, 0, sizeof(*data));
2066 memset(&cmd[0], 0, 12);
2067
2068 dbd = sdev->set_dbd_for_ms ? 8 : dbd;
2069 cmd[1] = dbd & 0x18;
2070 cmd[2] = modepage;
2071
2072
2073 if (!sshdr)
2074 sshdr = &my_sshdr;
2075
2076 retry:
2077 use_10_for_ms = sdev->use_10_for_ms;
2078
2079 if (use_10_for_ms) {
2080 if (len < 8)
2081 len = 8;
2082
2083 cmd[0] = MODE_SENSE_10;
2084 cmd[8] = len;
2085 header_length = 8;
2086 } else {
2087 if (len < 4)
2088 len = 4;
2089
2090 cmd[0] = MODE_SENSE;
2091 cmd[4] = len;
2092 header_length = 4;
2093 }
2094
2095 memset(buffer, 0, len);
2096
2097 result = scsi_execute_req(sdev, cmd, DMA_FROM_DEVICE, buffer, len,
2098 sshdr, timeout, retries, NULL);
2099
2100
2101
2102
2103
2104
2105 if (use_10_for_ms && !scsi_status_is_good(result) &&
2106 driver_byte(result) == DRIVER_SENSE) {
2107 if (scsi_sense_valid(sshdr)) {
2108 if ((sshdr->sense_key == ILLEGAL_REQUEST) &&
2109 (sshdr->asc == 0x20) && (sshdr->ascq == 0)) {
2110
2111
2112
2113 sdev->use_10_for_ms = 0;
2114 goto retry;
2115 }
2116 }
2117 }
2118
2119 if (scsi_status_is_good(result)) {
2120 if (unlikely(buffer[0] == 0x86 && buffer[1] == 0x0b &&
2121 (modepage == 6 || modepage == 8))) {
2122
2123 header_length = 0;
2124 data->length = 13;
2125 data->medium_type = 0;
2126 data->device_specific = 0;
2127 data->longlba = 0;
2128 data->block_descriptor_length = 0;
2129 } else if (use_10_for_ms) {
2130 data->length = buffer[0]*256 + buffer[1] + 2;
2131 data->medium_type = buffer[2];
2132 data->device_specific = buffer[3];
2133 data->longlba = buffer[4] & 0x01;
2134 data->block_descriptor_length = buffer[6]*256
2135 + buffer[7];
2136 } else {
2137 data->length = buffer[0] + 1;
2138 data->medium_type = buffer[1];
2139 data->device_specific = buffer[2];
2140 data->block_descriptor_length = buffer[3];
2141 }
2142 data->header_length = header_length;
2143 } else if ((status_byte(result) == CHECK_CONDITION) &&
2144 scsi_sense_valid(sshdr) &&
2145 sshdr->sense_key == UNIT_ATTENTION && retry_count) {
2146 retry_count--;
2147 goto retry;
2148 }
2149
2150 return result;
2151}
2152EXPORT_SYMBOL(scsi_mode_sense);
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164int
2165scsi_test_unit_ready(struct scsi_device *sdev, int timeout, int retries,
2166 struct scsi_sense_hdr *sshdr)
2167{
2168 char cmd[] = {
2169 TEST_UNIT_READY, 0, 0, 0, 0, 0,
2170 };
2171 int result;
2172
2173
2174 do {
2175 result = scsi_execute_req(sdev, cmd, DMA_NONE, NULL, 0, sshdr,
2176 timeout, 1, NULL);
2177 if (sdev->removable && scsi_sense_valid(sshdr) &&
2178 sshdr->sense_key == UNIT_ATTENTION)
2179 sdev->changed = 1;
2180 } while (scsi_sense_valid(sshdr) &&
2181 sshdr->sense_key == UNIT_ATTENTION && --retries);
2182
2183 return result;
2184}
2185EXPORT_SYMBOL(scsi_test_unit_ready);
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195int
2196scsi_device_set_state(struct scsi_device *sdev, enum scsi_device_state state)
2197{
2198 enum scsi_device_state oldstate = sdev->sdev_state;
2199
2200 if (state == oldstate)
2201 return 0;
2202
2203 switch (state) {
2204 case SDEV_CREATED:
2205 switch (oldstate) {
2206 case SDEV_CREATED_BLOCK:
2207 break;
2208 default:
2209 goto illegal;
2210 }
2211 break;
2212
2213 case SDEV_RUNNING:
2214 switch (oldstate) {
2215 case SDEV_CREATED:
2216 case SDEV_OFFLINE:
2217 case SDEV_TRANSPORT_OFFLINE:
2218 case SDEV_QUIESCE:
2219 case SDEV_BLOCK:
2220 break;
2221 default:
2222 goto illegal;
2223 }
2224 break;
2225
2226 case SDEV_QUIESCE:
2227 switch (oldstate) {
2228 case SDEV_RUNNING:
2229 case SDEV_OFFLINE:
2230 case SDEV_TRANSPORT_OFFLINE:
2231 break;
2232 default:
2233 goto illegal;
2234 }
2235 break;
2236
2237 case SDEV_OFFLINE:
2238 case SDEV_TRANSPORT_OFFLINE:
2239 switch (oldstate) {
2240 case SDEV_CREATED:
2241 case SDEV_RUNNING:
2242 case SDEV_QUIESCE:
2243 case SDEV_BLOCK:
2244 break;
2245 default:
2246 goto illegal;
2247 }
2248 break;
2249
2250 case SDEV_BLOCK:
2251 switch (oldstate) {
2252 case SDEV_RUNNING:
2253 case SDEV_CREATED_BLOCK:
2254 case SDEV_QUIESCE:
2255 case SDEV_OFFLINE:
2256 break;
2257 default:
2258 goto illegal;
2259 }
2260 break;
2261
2262 case SDEV_CREATED_BLOCK:
2263 switch (oldstate) {
2264 case SDEV_CREATED:
2265 break;
2266 default:
2267 goto illegal;
2268 }
2269 break;
2270
2271 case SDEV_CANCEL:
2272 switch (oldstate) {
2273 case SDEV_CREATED:
2274 case SDEV_RUNNING:
2275 case SDEV_QUIESCE:
2276 case SDEV_OFFLINE:
2277 case SDEV_TRANSPORT_OFFLINE:
2278 break;
2279 default:
2280 goto illegal;
2281 }
2282 break;
2283
2284 case SDEV_DEL:
2285 switch (oldstate) {
2286 case SDEV_CREATED:
2287 case SDEV_RUNNING:
2288 case SDEV_OFFLINE:
2289 case SDEV_TRANSPORT_OFFLINE:
2290 case SDEV_CANCEL:
2291 case SDEV_BLOCK:
2292 case SDEV_CREATED_BLOCK:
2293 break;
2294 default:
2295 goto illegal;
2296 }
2297 break;
2298
2299 }
2300 sdev->offline_already = false;
2301 sdev->sdev_state = state;
2302 return 0;
2303
2304 illegal:
2305 SCSI_LOG_ERROR_RECOVERY(1,
2306 sdev_printk(KERN_ERR, sdev,
2307 "Illegal state transition %s->%s",
2308 scsi_device_state_name(oldstate),
2309 scsi_device_state_name(state))
2310 );
2311 return -EINVAL;
2312}
2313EXPORT_SYMBOL(scsi_device_set_state);
2314
2315
2316
2317
2318
2319
2320
2321
2322static void scsi_evt_emit(struct scsi_device *sdev, struct scsi_event *evt)
2323{
2324 int idx = 0;
2325 char *envp[3];
2326
2327 switch (evt->evt_type) {
2328 case SDEV_EVT_MEDIA_CHANGE:
2329 envp[idx++] = "SDEV_MEDIA_CHANGE=1";
2330 break;
2331 case SDEV_EVT_INQUIRY_CHANGE_REPORTED:
2332 scsi_rescan_device(&sdev->sdev_gendev);
2333 envp[idx++] = "SDEV_UA=INQUIRY_DATA_HAS_CHANGED";
2334 break;
2335 case SDEV_EVT_CAPACITY_CHANGE_REPORTED:
2336 envp[idx++] = "SDEV_UA=CAPACITY_DATA_HAS_CHANGED";
2337 break;
2338 case SDEV_EVT_SOFT_THRESHOLD_REACHED_REPORTED:
2339 envp[idx++] = "SDEV_UA=THIN_PROVISIONING_SOFT_THRESHOLD_REACHED";
2340 break;
2341 case SDEV_EVT_MODE_PARAMETER_CHANGE_REPORTED:
2342 envp[idx++] = "SDEV_UA=MODE_PARAMETERS_CHANGED";
2343 break;
2344 case SDEV_EVT_LUN_CHANGE_REPORTED:
2345 envp[idx++] = "SDEV_UA=REPORTED_LUNS_DATA_HAS_CHANGED";
2346 break;
2347 case SDEV_EVT_ALUA_STATE_CHANGE_REPORTED:
2348 envp[idx++] = "SDEV_UA=ASYMMETRIC_ACCESS_STATE_CHANGED";
2349 break;
2350 case SDEV_EVT_POWER_ON_RESET_OCCURRED:
2351 envp[idx++] = "SDEV_UA=POWER_ON_RESET_OCCURRED";
2352 break;
2353 default:
2354
2355 break;
2356 }
2357
2358 envp[idx++] = NULL;
2359
2360 kobject_uevent_env(&sdev->sdev_gendev.kobj, KOBJ_CHANGE, envp);
2361}
2362
2363
2364
2365
2366
2367
2368
2369
2370void scsi_evt_thread(struct work_struct *work)
2371{
2372 struct scsi_device *sdev;
2373 enum scsi_device_event evt_type;
2374 LIST_HEAD(event_list);
2375
2376 sdev = container_of(work, struct scsi_device, event_work);
2377
2378 for (evt_type = SDEV_EVT_FIRST; evt_type <= SDEV_EVT_LAST; evt_type++)
2379 if (test_and_clear_bit(evt_type, sdev->pending_events))
2380 sdev_evt_send_simple(sdev, evt_type, GFP_KERNEL);
2381
2382 while (1) {
2383 struct scsi_event *evt;
2384 struct list_head *this, *tmp;
2385 unsigned long flags;
2386
2387 spin_lock_irqsave(&sdev->list_lock, flags);
2388 list_splice_init(&sdev->event_list, &event_list);
2389 spin_unlock_irqrestore(&sdev->list_lock, flags);
2390
2391 if (list_empty(&event_list))
2392 break;
2393
2394 list_for_each_safe(this, tmp, &event_list) {
2395 evt = list_entry(this, struct scsi_event, node);
2396 list_del(&evt->node);
2397 scsi_evt_emit(sdev, evt);
2398 kfree(evt);
2399 }
2400 }
2401}
2402
2403
2404
2405
2406
2407
2408
2409
2410void sdev_evt_send(struct scsi_device *sdev, struct scsi_event *evt)
2411{
2412 unsigned long flags;
2413
2414#if 0
2415
2416
2417
2418 if (!test_bit(evt->evt_type, sdev->supported_events)) {
2419 kfree(evt);
2420 return;
2421 }
2422#endif
2423
2424 spin_lock_irqsave(&sdev->list_lock, flags);
2425 list_add_tail(&evt->node, &sdev->event_list);
2426 schedule_work(&sdev->event_work);
2427 spin_unlock_irqrestore(&sdev->list_lock, flags);
2428}
2429EXPORT_SYMBOL_GPL(sdev_evt_send);
2430
2431
2432
2433
2434
2435
2436
2437
2438struct scsi_event *sdev_evt_alloc(enum scsi_device_event evt_type,
2439 gfp_t gfpflags)
2440{
2441 struct scsi_event *evt = kzalloc(sizeof(struct scsi_event), gfpflags);
2442 if (!evt)
2443 return NULL;
2444
2445 evt->evt_type = evt_type;
2446 INIT_LIST_HEAD(&evt->node);
2447
2448
2449 switch (evt_type) {
2450 case SDEV_EVT_MEDIA_CHANGE:
2451 case SDEV_EVT_INQUIRY_CHANGE_REPORTED:
2452 case SDEV_EVT_CAPACITY_CHANGE_REPORTED:
2453 case SDEV_EVT_SOFT_THRESHOLD_REACHED_REPORTED:
2454 case SDEV_EVT_MODE_PARAMETER_CHANGE_REPORTED:
2455 case SDEV_EVT_LUN_CHANGE_REPORTED:
2456 case SDEV_EVT_ALUA_STATE_CHANGE_REPORTED:
2457 case SDEV_EVT_POWER_ON_RESET_OCCURRED:
2458 default:
2459
2460 break;
2461 }
2462
2463 return evt;
2464}
2465EXPORT_SYMBOL_GPL(sdev_evt_alloc);
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475void sdev_evt_send_simple(struct scsi_device *sdev,
2476 enum scsi_device_event evt_type, gfp_t gfpflags)
2477{
2478 struct scsi_event *evt = sdev_evt_alloc(evt_type, gfpflags);
2479 if (!evt) {
2480 sdev_printk(KERN_ERR, sdev, "event %d eaten due to OOM\n",
2481 evt_type);
2482 return;
2483 }
2484
2485 sdev_evt_send(sdev, evt);
2486}
2487EXPORT_SYMBOL_GPL(sdev_evt_send_simple);
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504int
2505scsi_device_quiesce(struct scsi_device *sdev)
2506{
2507 struct request_queue *q = sdev->request_queue;
2508 int err;
2509
2510
2511
2512
2513
2514
2515 WARN_ON_ONCE(sdev->quiesced_by && sdev->quiesced_by != current);
2516
2517 if (sdev->quiesced_by == current)
2518 return 0;
2519
2520 blk_set_pm_only(q);
2521
2522 blk_mq_freeze_queue(q);
2523
2524
2525
2526
2527
2528
2529 synchronize_rcu();
2530 blk_mq_unfreeze_queue(q);
2531
2532 mutex_lock(&sdev->state_mutex);
2533 err = scsi_device_set_state(sdev, SDEV_QUIESCE);
2534 if (err == 0)
2535 sdev->quiesced_by = current;
2536 else
2537 blk_clear_pm_only(q);
2538 mutex_unlock(&sdev->state_mutex);
2539
2540 return err;
2541}
2542EXPORT_SYMBOL(scsi_device_quiesce);
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553void scsi_device_resume(struct scsi_device *sdev)
2554{
2555
2556
2557
2558
2559 mutex_lock(&sdev->state_mutex);
2560 if (sdev->quiesced_by) {
2561 sdev->quiesced_by = NULL;
2562 blk_clear_pm_only(sdev->request_queue);
2563 }
2564 if (sdev->sdev_state == SDEV_QUIESCE)
2565 scsi_device_set_state(sdev, SDEV_RUNNING);
2566 mutex_unlock(&sdev->state_mutex);
2567}
2568EXPORT_SYMBOL(scsi_device_resume);
2569
2570static void
2571device_quiesce_fn(struct scsi_device *sdev, void *data)
2572{
2573 scsi_device_quiesce(sdev);
2574}
2575
2576void
2577scsi_target_quiesce(struct scsi_target *starget)
2578{
2579 starget_for_each_device(starget, NULL, device_quiesce_fn);
2580}
2581EXPORT_SYMBOL(scsi_target_quiesce);
2582
2583static void
2584device_resume_fn(struct scsi_device *sdev, void *data)
2585{
2586 scsi_device_resume(sdev);
2587}
2588
2589void
2590scsi_target_resume(struct scsi_target *starget)
2591{
2592 starget_for_each_device(starget, NULL, device_resume_fn);
2593}
2594EXPORT_SYMBOL(scsi_target_resume);
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
2610int scsi_internal_device_block_nowait(struct scsi_device *sdev)
2611{
2612 struct request_queue *q = sdev->request_queue;
2613 int err = 0;
2614
2615 err = scsi_device_set_state(sdev, SDEV_BLOCK);
2616 if (err) {
2617 err = scsi_device_set_state(sdev, SDEV_CREATED_BLOCK);
2618
2619 if (err)
2620 return err;
2621 }
2622
2623
2624
2625
2626
2627
2628 blk_mq_quiesce_queue_nowait(q);
2629 return 0;
2630}
2631EXPORT_SYMBOL_GPL(scsi_internal_device_block_nowait);
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646
2647
2648static int scsi_internal_device_block(struct scsi_device *sdev)
2649{
2650 struct request_queue *q = sdev->request_queue;
2651 int err;
2652
2653 mutex_lock(&sdev->state_mutex);
2654 err = scsi_internal_device_block_nowait(sdev);
2655 if (err == 0)
2656 blk_mq_quiesce_queue(q);
2657 mutex_unlock(&sdev->state_mutex);
2658
2659 return err;
2660}
2661
2662void scsi_start_queue(struct scsi_device *sdev)
2663{
2664 struct request_queue *q = sdev->request_queue;
2665
2666 blk_mq_unquiesce_queue(q);
2667}
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684int scsi_internal_device_unblock_nowait(struct scsi_device *sdev,
2685 enum scsi_device_state new_state)
2686{
2687 switch (new_state) {
2688 case SDEV_RUNNING:
2689 case SDEV_TRANSPORT_OFFLINE:
2690 break;
2691 default:
2692 return -EINVAL;
2693 }
2694
2695
2696
2697
2698
2699 switch (sdev->sdev_state) {
2700 case SDEV_BLOCK:
2701 case SDEV_TRANSPORT_OFFLINE:
2702 sdev->sdev_state = new_state;
2703 break;
2704 case SDEV_CREATED_BLOCK:
2705 if (new_state == SDEV_TRANSPORT_OFFLINE ||
2706 new_state == SDEV_OFFLINE)
2707 sdev->sdev_state = new_state;
2708 else
2709 sdev->sdev_state = SDEV_CREATED;
2710 break;
2711 case SDEV_CANCEL:
2712 case SDEV_OFFLINE:
2713 break;
2714 default:
2715 return -EINVAL;
2716 }
2717 scsi_start_queue(sdev);
2718
2719 return 0;
2720}
2721EXPORT_SYMBOL_GPL(scsi_internal_device_unblock_nowait);
2722
2723
2724
2725
2726
2727
2728
2729
2730
2731
2732
2733
2734
2735
2736
2737static int scsi_internal_device_unblock(struct scsi_device *sdev,
2738 enum scsi_device_state new_state)
2739{
2740 int ret;
2741
2742 mutex_lock(&sdev->state_mutex);
2743 ret = scsi_internal_device_unblock_nowait(sdev, new_state);
2744 mutex_unlock(&sdev->state_mutex);
2745
2746 return ret;
2747}
2748
2749static void
2750device_block(struct scsi_device *sdev, void *data)
2751{
2752 int ret;
2753
2754 ret = scsi_internal_device_block(sdev);
2755
2756 WARN_ONCE(ret, "scsi_internal_device_block(%s) failed: ret = %d\n",
2757 dev_name(&sdev->sdev_gendev), ret);
2758}
2759
2760static int
2761target_block(struct device *dev, void *data)
2762{
2763 if (scsi_is_target_device(dev))
2764 starget_for_each_device(to_scsi_target(dev), NULL,
2765 device_block);
2766 return 0;
2767}
2768
2769void
2770scsi_target_block(struct device *dev)
2771{
2772 if (scsi_is_target_device(dev))
2773 starget_for_each_device(to_scsi_target(dev), NULL,
2774 device_block);
2775 else
2776 device_for_each_child(dev, NULL, target_block);
2777}
2778EXPORT_SYMBOL_GPL(scsi_target_block);
2779
2780static void
2781device_unblock(struct scsi_device *sdev, void *data)
2782{
2783 scsi_internal_device_unblock(sdev, *(enum scsi_device_state *)data);
2784}
2785
2786static int
2787target_unblock(struct device *dev, void *data)
2788{
2789 if (scsi_is_target_device(dev))
2790 starget_for_each_device(to_scsi_target(dev), data,
2791 device_unblock);
2792 return 0;
2793}
2794
2795void
2796scsi_target_unblock(struct device *dev, enum scsi_device_state new_state)
2797{
2798 if (scsi_is_target_device(dev))
2799 starget_for_each_device(to_scsi_target(dev), &new_state,
2800 device_unblock);
2801 else
2802 device_for_each_child(dev, &new_state, target_unblock);
2803}
2804EXPORT_SYMBOL_GPL(scsi_target_unblock);
2805
2806int
2807scsi_host_block(struct Scsi_Host *shost)
2808{
2809 struct scsi_device *sdev;
2810 int ret = 0;
2811
2812
2813
2814
2815
2816 shost_for_each_device(sdev, shost) {
2817 mutex_lock(&sdev->state_mutex);
2818 ret = scsi_internal_device_block_nowait(sdev);
2819 mutex_unlock(&sdev->state_mutex);
2820 if (ret) {
2821 scsi_device_put(sdev);
2822 break;
2823 }
2824 }
2825
2826
2827
2828
2829
2830 WARN_ON_ONCE(shost->tag_set.flags & BLK_MQ_F_BLOCKING);
2831
2832 if (!ret)
2833 synchronize_rcu();
2834
2835 return ret;
2836}
2837EXPORT_SYMBOL_GPL(scsi_host_block);
2838
2839int
2840scsi_host_unblock(struct Scsi_Host *shost, int new_state)
2841{
2842 struct scsi_device *sdev;
2843 int ret = 0;
2844
2845 shost_for_each_device(sdev, shost) {
2846 ret = scsi_internal_device_unblock(sdev, new_state);
2847 if (ret) {
2848 scsi_device_put(sdev);
2849 break;
2850 }
2851 }
2852 return ret;
2853}
2854EXPORT_SYMBOL_GPL(scsi_host_unblock);
2855
2856
2857
2858
2859
2860
2861
2862
2863
2864
2865void *scsi_kmap_atomic_sg(struct scatterlist *sgl, int sg_count,
2866 size_t *offset, size_t *len)
2867{
2868 int i;
2869 size_t sg_len = 0, len_complete = 0;
2870 struct scatterlist *sg;
2871 struct page *page;
2872
2873 WARN_ON(!irqs_disabled());
2874
2875 for_each_sg(sgl, sg, sg_count, i) {
2876 len_complete = sg_len;
2877 sg_len += sg->length;
2878 if (sg_len > *offset)
2879 break;
2880 }
2881
2882 if (unlikely(i == sg_count)) {
2883 printk(KERN_ERR "%s: Bytes in sg: %zu, requested offset %zu, "
2884 "elements %d\n",
2885 __func__, sg_len, *offset, sg_count);
2886 WARN_ON(1);
2887 return NULL;
2888 }
2889
2890
2891 *offset = *offset - len_complete + sg->offset;
2892
2893
2894 page = nth_page(sg_page(sg), (*offset >> PAGE_SHIFT));
2895 *offset &= ~PAGE_MASK;
2896
2897
2898 sg_len = PAGE_SIZE - *offset;
2899 if (*len > sg_len)
2900 *len = sg_len;
2901
2902 return kmap_atomic(page);
2903}
2904EXPORT_SYMBOL(scsi_kmap_atomic_sg);
2905
2906
2907
2908
2909
2910void scsi_kunmap_atomic_sg(void *virt)
2911{
2912 kunmap_atomic(virt);
2913}
2914EXPORT_SYMBOL(scsi_kunmap_atomic_sg);
2915
2916void sdev_disable_disk_events(struct scsi_device *sdev)
2917{
2918 atomic_inc(&sdev->disk_events_disable_depth);
2919}
2920EXPORT_SYMBOL(sdev_disable_disk_events);
2921
2922void sdev_enable_disk_events(struct scsi_device *sdev)
2923{
2924 if (WARN_ON_ONCE(atomic_read(&sdev->disk_events_disable_depth) <= 0))
2925 return;
2926 atomic_dec(&sdev->disk_events_disable_depth);
2927}
2928EXPORT_SYMBOL(sdev_enable_disk_events);
2929
2930
2931
2932
2933
2934
2935
2936
2937
2938
2939
2940
2941
2942
2943
2944int scsi_vpd_lun_id(struct scsi_device *sdev, char *id, size_t id_len)
2945{
2946 u8 cur_id_type = 0xff;
2947 u8 cur_id_size = 0;
2948 const unsigned char *d, *cur_id_str;
2949 const struct scsi_vpd *vpd_pg83;
2950 int id_size = -EINVAL;
2951
2952 rcu_read_lock();
2953 vpd_pg83 = rcu_dereference(sdev->vpd_pg83);
2954 if (!vpd_pg83) {
2955 rcu_read_unlock();
2956 return -ENXIO;
2957 }
2958
2959
2960
2961
2962
2963
2964
2965
2966
2967
2968
2969
2970
2971
2972
2973
2974 if (id_len < 21) {
2975 rcu_read_unlock();
2976 return -EINVAL;
2977 }
2978
2979 memset(id, 0, id_len);
2980 d = vpd_pg83->data + 4;
2981 while (d < vpd_pg83->data + vpd_pg83->len) {
2982
2983 if ((d[1] & 0x30) != 0x00)
2984 goto next_desig;
2985
2986 switch (d[1] & 0xf) {
2987 case 0x1:
2988
2989 if (cur_id_size > d[3])
2990 break;
2991
2992 if (cur_id_type > 0x01 && cur_id_type != 0xff)
2993 break;
2994 cur_id_size = d[3];
2995 if (cur_id_size + 4 > id_len)
2996 cur_id_size = id_len - 4;
2997 cur_id_str = d + 4;
2998 cur_id_type = d[1] & 0xf;
2999 id_size = snprintf(id, id_len, "t10.%*pE",
3000 cur_id_size, cur_id_str);
3001 break;
3002 case 0x2:
3003
3004 if (cur_id_size > d[3])
3005 break;
3006
3007 if (cur_id_type == 0x3 &&
3008 cur_id_size == d[3])
3009 break;
3010 cur_id_size = d[3];
3011 cur_id_str = d + 4;
3012 cur_id_type = d[1] & 0xf;
3013 switch (cur_id_size) {
3014 case 8:
3015 id_size = snprintf(id, id_len,
3016 "eui.%8phN",
3017 cur_id_str);
3018 break;
3019 case 12:
3020 id_size = snprintf(id, id_len,
3021 "eui.%12phN",
3022 cur_id_str);
3023 break;
3024 case 16:
3025 id_size = snprintf(id, id_len,
3026 "eui.%16phN",
3027 cur_id_str);
3028 break;
3029 default:
3030 cur_id_size = 0;
3031 break;
3032 }
3033 break;
3034 case 0x3:
3035
3036 if (cur_id_size > d[3])
3037 break;
3038 cur_id_size = d[3];
3039 cur_id_str = d + 4;
3040 cur_id_type = d[1] & 0xf;
3041 switch (cur_id_size) {
3042 case 8:
3043 id_size = snprintf(id, id_len,
3044 "naa.%8phN",
3045 cur_id_str);
3046 break;
3047 case 16:
3048 id_size = snprintf(id, id_len,
3049 "naa.%16phN",
3050 cur_id_str);
3051 break;
3052 default:
3053 cur_id_size = 0;
3054 break;
3055 }
3056 break;
3057 case 0x8:
3058
3059 if (cur_id_size + 4 > d[3])
3060 break;
3061
3062 if (cur_id_size && d[3] > id_len)
3063 break;
3064 cur_id_size = id_size = d[3];
3065 cur_id_str = d + 4;
3066 cur_id_type = d[1] & 0xf;
3067 if (cur_id_size >= id_len)
3068 cur_id_size = id_len - 1;
3069 memcpy(id, cur_id_str, cur_id_size);
3070
3071 if (cur_id_size != id_size)
3072 cur_id_size = 6;
3073 break;
3074 default:
3075 break;
3076 }
3077next_desig:
3078 d += d[3] + 4;
3079 }
3080 rcu_read_unlock();
3081
3082 return id_size;
3083}
3084EXPORT_SYMBOL(scsi_vpd_lun_id);
3085
3086
3087
3088
3089
3090
3091
3092
3093
3094
3095int scsi_vpd_tpg_id(struct scsi_device *sdev, int *rel_id)
3096{
3097 const unsigned char *d;
3098 const struct scsi_vpd *vpd_pg83;
3099 int group_id = -EAGAIN, rel_port = -1;
3100
3101 rcu_read_lock();
3102 vpd_pg83 = rcu_dereference(sdev->vpd_pg83);
3103 if (!vpd_pg83) {
3104 rcu_read_unlock();
3105 return -ENXIO;
3106 }
3107
3108 d = vpd_pg83->data + 4;
3109 while (d < vpd_pg83->data + vpd_pg83->len) {
3110 switch (d[1] & 0xf) {
3111 case 0x4:
3112
3113 rel_port = get_unaligned_be16(&d[6]);
3114 break;
3115 case 0x5:
3116
3117 group_id = get_unaligned_be16(&d[6]);
3118 break;
3119 default:
3120 break;
3121 }
3122 d += d[3] + 4;
3123 }
3124 rcu_read_unlock();
3125
3126 if (group_id >= 0 && rel_id && rel_port != -1)
3127 *rel_id = rel_port;
3128
3129 return group_id;
3130}
3131EXPORT_SYMBOL(scsi_vpd_tpg_id);
3132