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41#include <linux/module.h>
42#include <linux/moduleparam.h>
43#include <linux/kernel.h>
44#include <linux/timer.h>
45#include <linux/string.h>
46#include <linux/slab.h>
47#include <linux/blkdev.h>
48#include <linux/delay.h>
49#include <linux/init.h>
50#include <linux/completion.h>
51#include <linux/unistd.h>
52#include <linux/spinlock.h>
53#include <linux/kmod.h>
54#include <linux/interrupt.h>
55#include <linux/notifier.h>
56#include <linux/cpu.h>
57#include <linux/mutex.h>
58#include <linux/async.h>
59#include <asm/unaligned.h>
60
61#include <scsi/scsi.h>
62#include <scsi/scsi_cmnd.h>
63#include <scsi/scsi_dbg.h>
64#include <scsi/scsi_device.h>
65#include <scsi/scsi_driver.h>
66#include <scsi/scsi_eh.h>
67#include <scsi/scsi_host.h>
68#include <scsi/scsi_tcq.h>
69
70#include "scsi_priv.h"
71#include "scsi_logging.h"
72
73#define CREATE_TRACE_POINTS
74#include <trace/events/scsi.h>
75
76
77
78
79
80
81
82
83
84unsigned int scsi_logging_level;
85#if defined(CONFIG_SCSI_LOGGING)
86EXPORT_SYMBOL(scsi_logging_level);
87#endif
88
89
90
91
92
93
94ASYNC_DOMAIN_EXCLUSIVE(scsi_sd_pm_domain);
95EXPORT_SYMBOL(scsi_sd_pm_domain);
96
97#ifdef CONFIG_SCSI_LOGGING
98void scsi_log_send(struct scsi_cmnd *cmd)
99{
100 unsigned int level;
101
102
103
104
105
106
107
108
109
110
111
112
113 if (unlikely(scsi_logging_level)) {
114 level = SCSI_LOG_LEVEL(SCSI_LOG_MLQUEUE_SHIFT,
115 SCSI_LOG_MLQUEUE_BITS);
116 if (level > 1) {
117 scmd_printk(KERN_INFO, cmd,
118 "Send: scmd 0x%p\n", cmd);
119 scsi_print_command(cmd);
120 }
121 }
122}
123
124void scsi_log_completion(struct scsi_cmnd *cmd, int disposition)
125{
126 unsigned int level;
127
128
129
130
131
132
133
134
135
136
137
138
139
140 if (unlikely(scsi_logging_level)) {
141 level = SCSI_LOG_LEVEL(SCSI_LOG_MLCOMPLETE_SHIFT,
142 SCSI_LOG_MLCOMPLETE_BITS);
143 if (((level > 0) && (cmd->result || disposition != SUCCESS)) ||
144 (level > 1)) {
145 scsi_print_result(cmd, "Done", disposition);
146 scsi_print_command(cmd);
147 if (scsi_status_is_check_condition(cmd->result))
148 scsi_print_sense(cmd);
149 if (level > 3)
150 scmd_printk(KERN_INFO, cmd,
151 "scsi host busy %d failed %d\n",
152 scsi_host_busy(cmd->device->host),
153 cmd->device->host->host_failed);
154 }
155 }
156}
157#endif
158
159
160
161
162
163
164
165
166
167void scsi_finish_command(struct scsi_cmnd *cmd)
168{
169 struct scsi_device *sdev = cmd->device;
170 struct scsi_target *starget = scsi_target(sdev);
171 struct Scsi_Host *shost = sdev->host;
172 struct scsi_driver *drv;
173 unsigned int good_bytes;
174
175 scsi_device_unbusy(sdev, cmd);
176
177
178
179
180
181 if (atomic_read(&shost->host_blocked))
182 atomic_set(&shost->host_blocked, 0);
183 if (atomic_read(&starget->target_blocked))
184 atomic_set(&starget->target_blocked, 0);
185 if (atomic_read(&sdev->device_blocked))
186 atomic_set(&sdev->device_blocked, 0);
187
188 SCSI_LOG_MLCOMPLETE(4, sdev_printk(KERN_INFO, sdev,
189 "Notifying upper driver of completion "
190 "(result %x)\n", cmd->result));
191
192 good_bytes = scsi_bufflen(cmd);
193 if (!blk_rq_is_passthrough(scsi_cmd_to_rq(cmd))) {
194 int old_good_bytes = good_bytes;
195 drv = scsi_cmd_to_driver(cmd);
196 if (drv->done)
197 good_bytes = drv->done(cmd);
198
199
200
201
202
203
204 if (good_bytes == old_good_bytes)
205 good_bytes -= scsi_get_resid(cmd);
206 }
207 scsi_io_completion(cmd, good_bytes);
208}
209
210
211
212
213
214int scsi_device_max_queue_depth(struct scsi_device *sdev)
215{
216 return max_t(int, sdev->host->can_queue, 1024);
217}
218
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224
225
226int scsi_change_queue_depth(struct scsi_device *sdev, int depth)
227{
228 depth = min_t(int, depth, scsi_device_max_queue_depth(sdev));
229
230 if (depth > 0) {
231 sdev->queue_depth = depth;
232 wmb();
233 }
234
235 if (sdev->request_queue)
236 blk_set_queue_depth(sdev->request_queue, depth);
237
238 sbitmap_resize(&sdev->budget_map, sdev->queue_depth);
239
240 return sdev->queue_depth;
241}
242EXPORT_SYMBOL(scsi_change_queue_depth);
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262
263int scsi_track_queue_full(struct scsi_device *sdev, int depth)
264{
265
266
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268
269
270
271 if ((jiffies >> 4) == (sdev->last_queue_full_time >> 4))
272 return 0;
273
274 sdev->last_queue_full_time = jiffies;
275 if (sdev->last_queue_full_depth != depth) {
276 sdev->last_queue_full_count = 1;
277 sdev->last_queue_full_depth = depth;
278 } else {
279 sdev->last_queue_full_count++;
280 }
281
282 if (sdev->last_queue_full_count <= 10)
283 return 0;
284
285 return scsi_change_queue_depth(sdev, depth);
286}
287EXPORT_SYMBOL(scsi_track_queue_full);
288
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300
301static int scsi_vpd_inquiry(struct scsi_device *sdev, unsigned char *buffer,
302 u8 page, unsigned len)
303{
304 int result;
305 unsigned char cmd[16];
306
307 if (len < 4)
308 return -EINVAL;
309
310 cmd[0] = INQUIRY;
311 cmd[1] = 1;
312 cmd[2] = page;
313 cmd[3] = len >> 8;
314 cmd[4] = len & 0xff;
315 cmd[5] = 0;
316
317
318
319
320
321 result = scsi_execute_req(sdev, cmd, DMA_FROM_DEVICE, buffer,
322 len, NULL, 30 * HZ, 3, NULL);
323 if (result)
324 return -EIO;
325
326
327 if (buffer[1] != page)
328 return -EIO;
329
330 return get_unaligned_be16(&buffer[2]) + 4;
331}
332
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346
347int scsi_get_vpd_page(struct scsi_device *sdev, u8 page, unsigned char *buf,
348 int buf_len)
349{
350 int i, result;
351
352 if (sdev->skip_vpd_pages)
353 goto fail;
354
355
356 result = scsi_vpd_inquiry(sdev, buf, 0, buf_len);
357 if (result < 4)
358 goto fail;
359
360
361 if (page == 0)
362 return 0;
363
364 for (i = 4; i < min(result, buf_len); i++)
365 if (buf[i] == page)
366 goto found;
367
368 if (i < result && i >= buf_len)
369
370 goto found;
371
372 goto fail;
373
374 found:
375 result = scsi_vpd_inquiry(sdev, buf, page, buf_len);
376 if (result < 0)
377 goto fail;
378
379 return 0;
380
381 fail:
382 return -EINVAL;
383}
384EXPORT_SYMBOL_GPL(scsi_get_vpd_page);
385
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391
392
393static struct scsi_vpd *scsi_get_vpd_buf(struct scsi_device *sdev, u8 page)
394{
395 struct scsi_vpd *vpd_buf;
396 int vpd_len = SCSI_VPD_PG_LEN, result;
397
398retry_pg:
399 vpd_buf = kmalloc(sizeof(*vpd_buf) + vpd_len, GFP_KERNEL);
400 if (!vpd_buf)
401 return NULL;
402
403 result = scsi_vpd_inquiry(sdev, vpd_buf->data, page, vpd_len);
404 if (result < 0) {
405 kfree(vpd_buf);
406 return NULL;
407 }
408 if (result > vpd_len) {
409 vpd_len = result;
410 kfree(vpd_buf);
411 goto retry_pg;
412 }
413
414 vpd_buf->len = result;
415
416 return vpd_buf;
417}
418
419static void scsi_update_vpd_page(struct scsi_device *sdev, u8 page,
420 struct scsi_vpd __rcu **sdev_vpd_buf)
421{
422 struct scsi_vpd *vpd_buf;
423
424 vpd_buf = scsi_get_vpd_buf(sdev, page);
425 if (!vpd_buf)
426 return;
427
428 mutex_lock(&sdev->inquiry_mutex);
429 vpd_buf = rcu_replace_pointer(*sdev_vpd_buf, vpd_buf,
430 lockdep_is_held(&sdev->inquiry_mutex));
431 mutex_unlock(&sdev->inquiry_mutex);
432
433 if (vpd_buf)
434 kfree_rcu(vpd_buf, rcu);
435}
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444
445
446void scsi_attach_vpd(struct scsi_device *sdev)
447{
448 int i;
449 struct scsi_vpd *vpd_buf;
450
451 if (!scsi_device_supports_vpd(sdev))
452 return;
453
454
455 vpd_buf = scsi_get_vpd_buf(sdev, 0);
456 if (!vpd_buf)
457 return;
458
459 for (i = 4; i < vpd_buf->len; i++) {
460 if (vpd_buf->data[i] == 0x0)
461 scsi_update_vpd_page(sdev, 0x0, &sdev->vpd_pg0);
462 if (vpd_buf->data[i] == 0x80)
463 scsi_update_vpd_page(sdev, 0x80, &sdev->vpd_pg80);
464 if (vpd_buf->data[i] == 0x83)
465 scsi_update_vpd_page(sdev, 0x83, &sdev->vpd_pg83);
466 if (vpd_buf->data[i] == 0x89)
467 scsi_update_vpd_page(sdev, 0x89, &sdev->vpd_pg89);
468 }
469 kfree(vpd_buf);
470}
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482
483int scsi_report_opcode(struct scsi_device *sdev, unsigned char *buffer,
484 unsigned int len, unsigned char opcode)
485{
486 unsigned char cmd[16];
487 struct scsi_sense_hdr sshdr;
488 int result;
489
490 if (sdev->no_report_opcodes || sdev->scsi_level < SCSI_SPC_3)
491 return -EINVAL;
492
493 memset(cmd, 0, 16);
494 cmd[0] = MAINTENANCE_IN;
495 cmd[1] = MI_REPORT_SUPPORTED_OPERATION_CODES;
496 cmd[2] = 1;
497 cmd[3] = opcode;
498 put_unaligned_be32(len, &cmd[6]);
499 memset(buffer, 0, len);
500
501 result = scsi_execute_req(sdev, cmd, DMA_FROM_DEVICE, buffer, len,
502 &sshdr, 30 * HZ, 3, NULL);
503
504 if (result < 0)
505 return result;
506 if (result && scsi_sense_valid(&sshdr) &&
507 sshdr.sense_key == ILLEGAL_REQUEST &&
508 (sshdr.asc == 0x20 || sshdr.asc == 0x24) && sshdr.ascq == 0x00)
509 return -EINVAL;
510
511 if ((buffer[1] & 3) == 3)
512 return 1;
513
514 return 0;
515}
516EXPORT_SYMBOL(scsi_report_opcode);
517
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528
529int scsi_device_get(struct scsi_device *sdev)
530{
531 if (sdev->sdev_state == SDEV_DEL || sdev->sdev_state == SDEV_CANCEL)
532 goto fail;
533 if (!get_device(&sdev->sdev_gendev))
534 goto fail;
535 if (!try_module_get(sdev->host->hostt->module))
536 goto fail_put_device;
537 return 0;
538
539fail_put_device:
540 put_device(&sdev->sdev_gendev);
541fail:
542 return -ENXIO;
543}
544EXPORT_SYMBOL(scsi_device_get);
545
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553
554void scsi_device_put(struct scsi_device *sdev)
555{
556 struct module *mod = sdev->host->hostt->module;
557
558 put_device(&sdev->sdev_gendev);
559 module_put(mod);
560}
561EXPORT_SYMBOL(scsi_device_put);
562
563
564struct scsi_device *__scsi_iterate_devices(struct Scsi_Host *shost,
565 struct scsi_device *prev)
566{
567 struct list_head *list = (prev ? &prev->siblings : &shost->__devices);
568 struct scsi_device *next = NULL;
569 unsigned long flags;
570
571 spin_lock_irqsave(shost->host_lock, flags);
572 while (list->next != &shost->__devices) {
573 next = list_entry(list->next, struct scsi_device, siblings);
574
575 if (!scsi_device_get(next))
576 break;
577 next = NULL;
578 list = list->next;
579 }
580 spin_unlock_irqrestore(shost->host_lock, flags);
581
582 if (prev)
583 scsi_device_put(prev);
584 return next;
585}
586EXPORT_SYMBOL(__scsi_iterate_devices);
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597
598void starget_for_each_device(struct scsi_target *starget, void *data,
599 void (*fn)(struct scsi_device *, void *))
600{
601 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
602 struct scsi_device *sdev;
603
604 shost_for_each_device(sdev, shost) {
605 if ((sdev->channel == starget->channel) &&
606 (sdev->id == starget->id))
607 fn(sdev, data);
608 }
609}
610EXPORT_SYMBOL(starget_for_each_device);
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619
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621
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625
626void __starget_for_each_device(struct scsi_target *starget, void *data,
627 void (*fn)(struct scsi_device *, void *))
628{
629 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
630 struct scsi_device *sdev;
631
632 __shost_for_each_device(sdev, shost) {
633 if ((sdev->channel == starget->channel) &&
634 (sdev->id == starget->id))
635 fn(sdev, data);
636 }
637}
638EXPORT_SYMBOL(__starget_for_each_device);
639
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654
655struct scsi_device *__scsi_device_lookup_by_target(struct scsi_target *starget,
656 u64 lun)
657{
658 struct scsi_device *sdev;
659
660 list_for_each_entry(sdev, &starget->devices, same_target_siblings) {
661 if (sdev->sdev_state == SDEV_DEL)
662 continue;
663 if (sdev->lun ==lun)
664 return sdev;
665 }
666
667 return NULL;
668}
669EXPORT_SYMBOL(__scsi_device_lookup_by_target);
670
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678
679
680struct scsi_device *scsi_device_lookup_by_target(struct scsi_target *starget,
681 u64 lun)
682{
683 struct scsi_device *sdev;
684 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
685 unsigned long flags;
686
687 spin_lock_irqsave(shost->host_lock, flags);
688 sdev = __scsi_device_lookup_by_target(starget, lun);
689 if (sdev && scsi_device_get(sdev))
690 sdev = NULL;
691 spin_unlock_irqrestore(shost->host_lock, flags);
692
693 return sdev;
694}
695EXPORT_SYMBOL(scsi_device_lookup_by_target);
696
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712
713struct scsi_device *__scsi_device_lookup(struct Scsi_Host *shost,
714 uint channel, uint id, u64 lun)
715{
716 struct scsi_device *sdev;
717
718 list_for_each_entry(sdev, &shost->__devices, siblings) {
719 if (sdev->sdev_state == SDEV_DEL)
720 continue;
721 if (sdev->channel == channel && sdev->id == id &&
722 sdev->lun ==lun)
723 return sdev;
724 }
725
726 return NULL;
727}
728EXPORT_SYMBOL(__scsi_device_lookup);
729
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739
740
741struct scsi_device *scsi_device_lookup(struct Scsi_Host *shost,
742 uint channel, uint id, u64 lun)
743{
744 struct scsi_device *sdev;
745 unsigned long flags;
746
747 spin_lock_irqsave(shost->host_lock, flags);
748 sdev = __scsi_device_lookup(shost, channel, id, lun);
749 if (sdev && scsi_device_get(sdev))
750 sdev = NULL;
751 spin_unlock_irqrestore(shost->host_lock, flags);
752
753 return sdev;
754}
755EXPORT_SYMBOL(scsi_device_lookup);
756
757MODULE_DESCRIPTION("SCSI core");
758MODULE_LICENSE("GPL");
759
760module_param(scsi_logging_level, int, S_IRUGO|S_IWUSR);
761MODULE_PARM_DESC(scsi_logging_level, "a bit mask of logging levels");
762
763static int __init init_scsi(void)
764{
765 int error;
766
767 error = scsi_init_procfs();
768 if (error)
769 goto cleanup_queue;
770 error = scsi_init_devinfo();
771 if (error)
772 goto cleanup_procfs;
773 error = scsi_init_hosts();
774 if (error)
775 goto cleanup_devlist;
776 error = scsi_init_sysctl();
777 if (error)
778 goto cleanup_hosts;
779 error = scsi_sysfs_register();
780 if (error)
781 goto cleanup_sysctl;
782
783 scsi_netlink_init();
784
785 printk(KERN_NOTICE "SCSI subsystem initialized\n");
786 return 0;
787
788cleanup_sysctl:
789 scsi_exit_sysctl();
790cleanup_hosts:
791 scsi_exit_hosts();
792cleanup_devlist:
793 scsi_exit_devinfo();
794cleanup_procfs:
795 scsi_exit_procfs();
796cleanup_queue:
797 scsi_exit_queue();
798 printk(KERN_ERR "SCSI subsystem failed to initialize, error = %d\n",
799 -error);
800 return error;
801}
802
803static void __exit exit_scsi(void)
804{
805 scsi_netlink_exit();
806 scsi_sysfs_unregister();
807 scsi_exit_sysctl();
808 scsi_exit_hosts();
809 scsi_exit_devinfo();
810 scsi_exit_procfs();
811 scsi_exit_queue();
812}
813
814subsys_initcall(init_scsi);
815module_exit(exit_scsi);
816