1
2
3
4
5#include <linux/module.h>
6#include <linux/fs.h>
7#include <linux/genhd.h>
8#include <linux/kdev_t.h>
9#include <linux/kernel.h>
10#include <linux/blkdev.h>
11#include <linux/backing-dev.h>
12#include <linux/init.h>
13#include <linux/spinlock.h>
14#include <linux/proc_fs.h>
15#include <linux/seq_file.h>
16#include <linux/slab.h>
17#include <linux/kmod.h>
18#include <linux/kobj_map.h>
19#include <linux/mutex.h>
20#include <linux/idr.h>
21#include <linux/log2.h>
22#include <linux/pm_runtime.h>
23#include <linux/badblocks.h>
24
25#include "blk.h"
26
27static DEFINE_MUTEX(block_class_lock);
28struct kobject *block_depr;
29
30
31#define NR_EXT_DEVT (1 << MINORBITS)
32
33
34
35
36static DEFINE_SPINLOCK(ext_devt_lock);
37static DEFINE_IDR(ext_devt_idr);
38
39static struct device_type disk_type;
40
41static void disk_check_events(struct disk_events *ev,
42 unsigned int *clearing_ptr);
43static void disk_alloc_events(struct gendisk *disk);
44static void disk_add_events(struct gendisk *disk);
45static void disk_del_events(struct gendisk *disk);
46static void disk_release_events(struct gendisk *disk);
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62struct hd_struct *disk_get_part(struct gendisk *disk, int partno)
63{
64 struct hd_struct *part = NULL;
65 struct disk_part_tbl *ptbl;
66
67 if (unlikely(partno < 0))
68 return NULL;
69
70 rcu_read_lock();
71
72 ptbl = rcu_dereference(disk->part_tbl);
73 if (likely(partno < ptbl->len)) {
74 part = rcu_dereference(ptbl->part[partno]);
75 if (part)
76 get_device(part_to_dev(part));
77 }
78
79 rcu_read_unlock();
80
81 return part;
82}
83EXPORT_SYMBOL_GPL(disk_get_part);
84
85
86
87
88
89
90
91
92
93
94
95
96void disk_part_iter_init(struct disk_part_iter *piter, struct gendisk *disk,
97 unsigned int flags)
98{
99 struct disk_part_tbl *ptbl;
100
101 rcu_read_lock();
102 ptbl = rcu_dereference(disk->part_tbl);
103
104 piter->disk = disk;
105 piter->part = NULL;
106
107 if (flags & DISK_PITER_REVERSE)
108 piter->idx = ptbl->len - 1;
109 else if (flags & (DISK_PITER_INCL_PART0 | DISK_PITER_INCL_EMPTY_PART0))
110 piter->idx = 0;
111 else
112 piter->idx = 1;
113
114 piter->flags = flags;
115
116 rcu_read_unlock();
117}
118EXPORT_SYMBOL_GPL(disk_part_iter_init);
119
120
121
122
123
124
125
126
127
128
129struct hd_struct *disk_part_iter_next(struct disk_part_iter *piter)
130{
131 struct disk_part_tbl *ptbl;
132 int inc, end;
133
134
135 disk_put_part(piter->part);
136 piter->part = NULL;
137
138
139 rcu_read_lock();
140 ptbl = rcu_dereference(piter->disk->part_tbl);
141
142
143 if (piter->flags & DISK_PITER_REVERSE) {
144 inc = -1;
145 if (piter->flags & (DISK_PITER_INCL_PART0 |
146 DISK_PITER_INCL_EMPTY_PART0))
147 end = -1;
148 else
149 end = 0;
150 } else {
151 inc = 1;
152 end = ptbl->len;
153 }
154
155
156 for (; piter->idx != end; piter->idx += inc) {
157 struct hd_struct *part;
158
159 part = rcu_dereference(ptbl->part[piter->idx]);
160 if (!part)
161 continue;
162 if (!part_nr_sects_read(part) &&
163 !(piter->flags & DISK_PITER_INCL_EMPTY) &&
164 !(piter->flags & DISK_PITER_INCL_EMPTY_PART0 &&
165 piter->idx == 0))
166 continue;
167
168 get_device(part_to_dev(part));
169 piter->part = part;
170 piter->idx += inc;
171 break;
172 }
173
174 rcu_read_unlock();
175
176 return piter->part;
177}
178EXPORT_SYMBOL_GPL(disk_part_iter_next);
179
180
181
182
183
184
185
186
187
188
189void disk_part_iter_exit(struct disk_part_iter *piter)
190{
191 disk_put_part(piter->part);
192 piter->part = NULL;
193}
194EXPORT_SYMBOL_GPL(disk_part_iter_exit);
195
196static inline int sector_in_part(struct hd_struct *part, sector_t sector)
197{
198 return part->start_sect <= sector &&
199 sector < part->start_sect + part_nr_sects_read(part);
200}
201
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203
204
205
206
207
208
209
210
211
212
213
214
215
216
217struct hd_struct *disk_map_sector_rcu(struct gendisk *disk, sector_t sector)
218{
219 struct disk_part_tbl *ptbl;
220 struct hd_struct *part;
221 int i;
222
223 ptbl = rcu_dereference(disk->part_tbl);
224
225 part = rcu_dereference(ptbl->last_lookup);
226 if (part && sector_in_part(part, sector))
227 return part;
228
229 for (i = 1; i < ptbl->len; i++) {
230 part = rcu_dereference(ptbl->part[i]);
231
232 if (part && sector_in_part(part, sector)) {
233 rcu_assign_pointer(ptbl->last_lookup, part);
234 return part;
235 }
236 }
237 return &disk->part0;
238}
239EXPORT_SYMBOL_GPL(disk_map_sector_rcu);
240
241
242
243
244
245static struct blk_major_name {
246 struct blk_major_name *next;
247 int major;
248 char name[16];
249} *major_names[BLKDEV_MAJOR_HASH_SIZE];
250
251
252static inline int major_to_index(unsigned major)
253{
254 return major % BLKDEV_MAJOR_HASH_SIZE;
255}
256
257#ifdef CONFIG_PROC_FS
258void blkdev_show(struct seq_file *seqf, off_t offset)
259{
260 struct blk_major_name *dp;
261
262 if (offset < BLKDEV_MAJOR_HASH_SIZE) {
263 mutex_lock(&block_class_lock);
264 for (dp = major_names[offset]; dp; dp = dp->next)
265 seq_printf(seqf, "%3d %s\n", dp->major, dp->name);
266 mutex_unlock(&block_class_lock);
267 }
268}
269#endif
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287int register_blkdev(unsigned int major, const char *name)
288{
289 struct blk_major_name **n, *p;
290 int index, ret = 0;
291
292 mutex_lock(&block_class_lock);
293
294
295 if (major == 0) {
296 for (index = ARRAY_SIZE(major_names)-1; index > 0; index--) {
297 if (major_names[index] == NULL)
298 break;
299 }
300
301 if (index == 0) {
302 printk("register_blkdev: failed to get major for %s\n",
303 name);
304 ret = -EBUSY;
305 goto out;
306 }
307 major = index;
308 ret = major;
309 }
310
311 p = kmalloc(sizeof(struct blk_major_name), GFP_KERNEL);
312 if (p == NULL) {
313 ret = -ENOMEM;
314 goto out;
315 }
316
317 p->major = major;
318 strlcpy(p->name, name, sizeof(p->name));
319 p->next = NULL;
320 index = major_to_index(major);
321
322 for (n = &major_names[index]; *n; n = &(*n)->next) {
323 if ((*n)->major == major)
324 break;
325 }
326 if (!*n)
327 *n = p;
328 else
329 ret = -EBUSY;
330
331 if (ret < 0) {
332 printk("register_blkdev: cannot get major %d for %s\n",
333 major, name);
334 kfree(p);
335 }
336out:
337 mutex_unlock(&block_class_lock);
338 return ret;
339}
340
341EXPORT_SYMBOL(register_blkdev);
342
343void unregister_blkdev(unsigned int major, const char *name)
344{
345 struct blk_major_name **n;
346 struct blk_major_name *p = NULL;
347 int index = major_to_index(major);
348
349 mutex_lock(&block_class_lock);
350 for (n = &major_names[index]; *n; n = &(*n)->next)
351 if ((*n)->major == major)
352 break;
353 if (!*n || strcmp((*n)->name, name)) {
354 WARN_ON(1);
355 } else {
356 p = *n;
357 *n = p->next;
358 }
359 mutex_unlock(&block_class_lock);
360 kfree(p);
361}
362
363EXPORT_SYMBOL(unregister_blkdev);
364
365static struct kobj_map *bdev_map;
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380static int blk_mangle_minor(int minor)
381{
382#ifdef CONFIG_DEBUG_BLOCK_EXT_DEVT
383 int i;
384
385 for (i = 0; i < MINORBITS / 2; i++) {
386 int low = minor & (1 << i);
387 int high = minor & (1 << (MINORBITS - 1 - i));
388 int distance = MINORBITS - 1 - 2 * i;
389
390 minor ^= low | high;
391 low <<= distance;
392 high >>= distance;
393 minor |= low | high;
394 }
395#endif
396 return minor;
397}
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413int blk_alloc_devt(struct hd_struct *part, dev_t *devt)
414{
415 struct gendisk *disk = part_to_disk(part);
416 int idx;
417
418
419 if (part->partno < disk->minors) {
420 *devt = MKDEV(disk->major, disk->first_minor + part->partno);
421 return 0;
422 }
423
424
425 idr_preload(GFP_KERNEL);
426
427 spin_lock_bh(&ext_devt_lock);
428 idx = idr_alloc(&ext_devt_idr, part, 0, NR_EXT_DEVT, GFP_NOWAIT);
429 spin_unlock_bh(&ext_devt_lock);
430
431 idr_preload_end();
432 if (idx < 0)
433 return idx == -ENOSPC ? -EBUSY : idx;
434
435 *devt = MKDEV(BLOCK_EXT_MAJOR, blk_mangle_minor(idx));
436 return 0;
437}
438
439
440
441
442
443
444
445
446
447
448void blk_free_devt(dev_t devt)
449{
450 if (devt == MKDEV(0, 0))
451 return;
452
453 if (MAJOR(devt) == BLOCK_EXT_MAJOR) {
454 spin_lock_bh(&ext_devt_lock);
455 idr_remove(&ext_devt_idr, blk_mangle_minor(MINOR(devt)));
456 spin_unlock_bh(&ext_devt_lock);
457 }
458}
459
460static char *bdevt_str(dev_t devt, char *buf)
461{
462 if (MAJOR(devt) <= 0xff && MINOR(devt) <= 0xff) {
463 char tbuf[BDEVT_SIZE];
464 snprintf(tbuf, BDEVT_SIZE, "%02x%02x", MAJOR(devt), MINOR(devt));
465 snprintf(buf, BDEVT_SIZE, "%-9s", tbuf);
466 } else
467 snprintf(buf, BDEVT_SIZE, "%03x:%05x", MAJOR(devt), MINOR(devt));
468
469 return buf;
470}
471
472
473
474
475
476
477void blk_register_region(dev_t devt, unsigned long range, struct module *module,
478 struct kobject *(*probe)(dev_t, int *, void *),
479 int (*lock)(dev_t, void *), void *data)
480{
481 kobj_map(bdev_map, devt, range, module, probe, lock, data);
482}
483
484EXPORT_SYMBOL(blk_register_region);
485
486void blk_unregister_region(dev_t devt, unsigned long range)
487{
488 kobj_unmap(bdev_map, devt, range);
489}
490
491EXPORT_SYMBOL(blk_unregister_region);
492
493static struct kobject *exact_match(dev_t devt, int *partno, void *data)
494{
495 struct gendisk *p = data;
496
497 return &disk_to_dev(p)->kobj;
498}
499
500static int exact_lock(dev_t devt, void *data)
501{
502 struct gendisk *p = data;
503
504 if (!get_disk(p))
505 return -1;
506 return 0;
507}
508
509static void register_disk(struct gendisk *disk)
510{
511 struct device *ddev = disk_to_dev(disk);
512 struct block_device *bdev;
513 struct disk_part_iter piter;
514 struct hd_struct *part;
515 int err;
516
517 ddev->parent = disk->driverfs_dev;
518
519 dev_set_name(ddev, "%s", disk->disk_name);
520
521
522 dev_set_uevent_suppress(ddev, 1);
523
524 if (device_add(ddev))
525 return;
526 if (!sysfs_deprecated) {
527 err = sysfs_create_link(block_depr, &ddev->kobj,
528 kobject_name(&ddev->kobj));
529 if (err) {
530 device_del(ddev);
531 return;
532 }
533 }
534
535
536
537
538
539
540 pm_runtime_set_memalloc_noio(ddev, true);
541
542 disk->part0.holder_dir = kobject_create_and_add("holders", &ddev->kobj);
543 disk->slave_dir = kobject_create_and_add("slaves", &ddev->kobj);
544
545
546 if (!disk_part_scan_enabled(disk))
547 goto exit;
548
549
550 if (!get_capacity(disk))
551 goto exit;
552
553 bdev = bdget_disk(disk, 0);
554 if (!bdev)
555 goto exit;
556
557 bdev->bd_invalidated = 1;
558 err = blkdev_get(bdev, FMODE_READ, NULL);
559 if (err < 0)
560 goto exit;
561 blkdev_put(bdev, FMODE_READ);
562
563exit:
564
565 dev_set_uevent_suppress(ddev, 0);
566 kobject_uevent(&ddev->kobj, KOBJ_ADD);
567
568
569 disk_part_iter_init(&piter, disk, 0);
570 while ((part = disk_part_iter_next(&piter)))
571 kobject_uevent(&part_to_dev(part)->kobj, KOBJ_ADD);
572 disk_part_iter_exit(&piter);
573}
574
575
576
577
578
579
580
581
582
583
584void add_disk(struct gendisk *disk)
585{
586 struct backing_dev_info *bdi;
587 dev_t devt;
588 int retval;
589
590
591
592
593
594 WARN_ON(disk->minors && !(disk->major || disk->first_minor));
595 WARN_ON(!disk->minors && !(disk->flags & GENHD_FL_EXT_DEVT));
596
597 disk->flags |= GENHD_FL_UP;
598
599 retval = blk_alloc_devt(&disk->part0, &devt);
600 if (retval) {
601 WARN_ON(1);
602 return;
603 }
604 disk_to_dev(disk)->devt = devt;
605
606
607
608
609 disk->major = MAJOR(devt);
610 disk->first_minor = MINOR(devt);
611
612 disk_alloc_events(disk);
613
614
615 bdi = &disk->queue->backing_dev_info;
616 bdi_register_dev(bdi, disk_devt(disk));
617
618 blk_register_region(disk_devt(disk), disk->minors, NULL,
619 exact_match, exact_lock, disk);
620 register_disk(disk);
621 blk_register_queue(disk);
622
623
624
625
626
627 WARN_ON_ONCE(!blk_get_queue(disk->queue));
628
629 retval = sysfs_create_link(&disk_to_dev(disk)->kobj, &bdi->dev->kobj,
630 "bdi");
631 WARN_ON(retval);
632
633 disk_add_events(disk);
634 blk_integrity_add(disk);
635}
636EXPORT_SYMBOL(add_disk);
637
638void del_gendisk(struct gendisk *disk)
639{
640 struct disk_part_iter piter;
641 struct hd_struct *part;
642
643 blk_integrity_del(disk);
644 disk_del_events(disk);
645
646
647 disk_part_iter_init(&piter, disk,
648 DISK_PITER_INCL_EMPTY | DISK_PITER_REVERSE);
649 while ((part = disk_part_iter_next(&piter))) {
650 invalidate_partition(disk, part->partno);
651 delete_partition(disk, part->partno);
652 }
653 disk_part_iter_exit(&piter);
654
655 invalidate_partition(disk, 0);
656 set_capacity(disk, 0);
657 disk->flags &= ~GENHD_FL_UP;
658
659 sysfs_remove_link(&disk_to_dev(disk)->kobj, "bdi");
660 blk_unregister_queue(disk);
661 blk_unregister_region(disk_devt(disk), disk->minors);
662
663 part_stat_set_all(&disk->part0, 0);
664 disk->part0.stamp = 0;
665
666 kobject_put(disk->part0.holder_dir);
667 kobject_put(disk->slave_dir);
668 if (!sysfs_deprecated)
669 sysfs_remove_link(block_depr, dev_name(disk_to_dev(disk)));
670 pm_runtime_set_memalloc_noio(disk_to_dev(disk), false);
671 device_del(disk_to_dev(disk));
672}
673EXPORT_SYMBOL(del_gendisk);
674
675
676static ssize_t disk_badblocks_show(struct device *dev,
677 struct device_attribute *attr,
678 char *page)
679{
680 struct gendisk *disk = dev_to_disk(dev);
681
682 if (!disk->bb)
683 return sprintf(page, "\n");
684
685 return badblocks_show(disk->bb, page, 0);
686}
687
688static ssize_t disk_badblocks_store(struct device *dev,
689 struct device_attribute *attr,
690 const char *page, size_t len)
691{
692 struct gendisk *disk = dev_to_disk(dev);
693
694 if (!disk->bb)
695 return -ENXIO;
696
697 return badblocks_store(disk->bb, page, len, 0);
698}
699
700
701
702
703
704
705
706
707
708struct gendisk *get_gendisk(dev_t devt, int *partno)
709{
710 struct gendisk *disk = NULL;
711
712 if (MAJOR(devt) != BLOCK_EXT_MAJOR) {
713 struct kobject *kobj;
714
715 kobj = kobj_lookup(bdev_map, devt, partno);
716 if (kobj)
717 disk = dev_to_disk(kobj_to_dev(kobj));
718 } else {
719 struct hd_struct *part;
720
721 spin_lock_bh(&ext_devt_lock);
722 part = idr_find(&ext_devt_idr, blk_mangle_minor(MINOR(devt)));
723 if (part && get_disk(part_to_disk(part))) {
724 *partno = part->partno;
725 disk = part_to_disk(part);
726 }
727 spin_unlock_bh(&ext_devt_lock);
728 }
729
730 return disk;
731}
732EXPORT_SYMBOL(get_gendisk);
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747struct block_device *bdget_disk(struct gendisk *disk, int partno)
748{
749 struct hd_struct *part;
750 struct block_device *bdev = NULL;
751
752 part = disk_get_part(disk, partno);
753 if (part)
754 bdev = bdget(part_devt(part));
755 disk_put_part(part);
756
757 return bdev;
758}
759EXPORT_SYMBOL(bdget_disk);
760
761
762
763
764
765
766void __init printk_all_partitions(void)
767{
768 struct class_dev_iter iter;
769 struct device *dev;
770
771 class_dev_iter_init(&iter, &block_class, NULL, &disk_type);
772 while ((dev = class_dev_iter_next(&iter))) {
773 struct gendisk *disk = dev_to_disk(dev);
774 struct disk_part_iter piter;
775 struct hd_struct *part;
776 char name_buf[BDEVNAME_SIZE];
777 char devt_buf[BDEVT_SIZE];
778
779
780
781
782
783 if (get_capacity(disk) == 0 ||
784 (disk->flags & GENHD_FL_SUPPRESS_PARTITION_INFO))
785 continue;
786
787
788
789
790
791
792 disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0);
793 while ((part = disk_part_iter_next(&piter))) {
794 bool is_part0 = part == &disk->part0;
795
796 printk("%s%s %10llu %s %s", is_part0 ? "" : " ",
797 bdevt_str(part_devt(part), devt_buf),
798 (unsigned long long)part_nr_sects_read(part) >> 1
799 , disk_name(disk, part->partno, name_buf),
800 part->info ? part->info->uuid : "");
801 if (is_part0) {
802 if (disk->driverfs_dev != NULL &&
803 disk->driverfs_dev->driver != NULL)
804 printk(" driver: %s\n",
805 disk->driverfs_dev->driver->name);
806 else
807 printk(" (driver?)\n");
808 } else
809 printk("\n");
810 }
811 disk_part_iter_exit(&piter);
812 }
813 class_dev_iter_exit(&iter);
814}
815
816#ifdef CONFIG_PROC_FS
817
818static void *disk_seqf_start(struct seq_file *seqf, loff_t *pos)
819{
820 loff_t skip = *pos;
821 struct class_dev_iter *iter;
822 struct device *dev;
823
824 iter = kmalloc(sizeof(*iter), GFP_KERNEL);
825 if (!iter)
826 return ERR_PTR(-ENOMEM);
827
828 seqf->private = iter;
829 class_dev_iter_init(iter, &block_class, NULL, &disk_type);
830 do {
831 dev = class_dev_iter_next(iter);
832 if (!dev)
833 return NULL;
834 } while (skip--);
835
836 return dev_to_disk(dev);
837}
838
839static void *disk_seqf_next(struct seq_file *seqf, void *v, loff_t *pos)
840{
841 struct device *dev;
842
843 (*pos)++;
844 dev = class_dev_iter_next(seqf->private);
845 if (dev)
846 return dev_to_disk(dev);
847
848 return NULL;
849}
850
851static void disk_seqf_stop(struct seq_file *seqf, void *v)
852{
853 struct class_dev_iter *iter = seqf->private;
854
855
856 if (iter) {
857 class_dev_iter_exit(iter);
858 kfree(iter);
859 }
860}
861
862static void *show_partition_start(struct seq_file *seqf, loff_t *pos)
863{
864 void *p;
865
866 p = disk_seqf_start(seqf, pos);
867 if (!IS_ERR_OR_NULL(p) && !*pos)
868 seq_puts(seqf, "major minor #blocks name\n\n");
869 return p;
870}
871
872static int show_partition(struct seq_file *seqf, void *v)
873{
874 struct gendisk *sgp = v;
875 struct disk_part_iter piter;
876 struct hd_struct *part;
877 char buf[BDEVNAME_SIZE];
878
879
880 if (!get_capacity(sgp) || (!disk_max_parts(sgp) &&
881 (sgp->flags & GENHD_FL_REMOVABLE)))
882 return 0;
883 if (sgp->flags & GENHD_FL_SUPPRESS_PARTITION_INFO)
884 return 0;
885
886
887 disk_part_iter_init(&piter, sgp, DISK_PITER_INCL_PART0);
888 while ((part = disk_part_iter_next(&piter)))
889 seq_printf(seqf, "%4d %7d %10llu %s\n",
890 MAJOR(part_devt(part)), MINOR(part_devt(part)),
891 (unsigned long long)part_nr_sects_read(part) >> 1,
892 disk_name(sgp, part->partno, buf));
893 disk_part_iter_exit(&piter);
894
895 return 0;
896}
897
898static const struct seq_operations partitions_op = {
899 .start = show_partition_start,
900 .next = disk_seqf_next,
901 .stop = disk_seqf_stop,
902 .show = show_partition
903};
904
905static int partitions_open(struct inode *inode, struct file *file)
906{
907 return seq_open(file, &partitions_op);
908}
909
910static const struct file_operations proc_partitions_operations = {
911 .open = partitions_open,
912 .read = seq_read,
913 .llseek = seq_lseek,
914 .release = seq_release,
915};
916#endif
917
918
919static struct kobject *base_probe(dev_t devt, int *partno, void *data)
920{
921 if (request_module("block-major-%d-%d", MAJOR(devt), MINOR(devt)) > 0)
922
923 request_module("block-major-%d", MAJOR(devt));
924 return NULL;
925}
926
927static int __init genhd_device_init(void)
928{
929 int error;
930
931 block_class.dev_kobj = sysfs_dev_block_kobj;
932 error = class_register(&block_class);
933 if (unlikely(error))
934 return error;
935 bdev_map = kobj_map_init(base_probe, &block_class_lock);
936 blk_dev_init();
937
938 register_blkdev(BLOCK_EXT_MAJOR, "blkext");
939
940
941 if (!sysfs_deprecated)
942 block_depr = kobject_create_and_add("block", NULL);
943 return 0;
944}
945
946subsys_initcall(genhd_device_init);
947
948static ssize_t disk_range_show(struct device *dev,
949 struct device_attribute *attr, char *buf)
950{
951 struct gendisk *disk = dev_to_disk(dev);
952
953 return sprintf(buf, "%d\n", disk->minors);
954}
955
956static ssize_t disk_ext_range_show(struct device *dev,
957 struct device_attribute *attr, char *buf)
958{
959 struct gendisk *disk = dev_to_disk(dev);
960
961 return sprintf(buf, "%d\n", disk_max_parts(disk));
962}
963
964static ssize_t disk_removable_show(struct device *dev,
965 struct device_attribute *attr, char *buf)
966{
967 struct gendisk *disk = dev_to_disk(dev);
968
969 return sprintf(buf, "%d\n",
970 (disk->flags & GENHD_FL_REMOVABLE ? 1 : 0));
971}
972
973static ssize_t disk_ro_show(struct device *dev,
974 struct device_attribute *attr, char *buf)
975{
976 struct gendisk *disk = dev_to_disk(dev);
977
978 return sprintf(buf, "%d\n", get_disk_ro(disk) ? 1 : 0);
979}
980
981static ssize_t disk_capability_show(struct device *dev,
982 struct device_attribute *attr, char *buf)
983{
984 struct gendisk *disk = dev_to_disk(dev);
985
986 return sprintf(buf, "%x\n", disk->flags);
987}
988
989static ssize_t disk_alignment_offset_show(struct device *dev,
990 struct device_attribute *attr,
991 char *buf)
992{
993 struct gendisk *disk = dev_to_disk(dev);
994
995 return sprintf(buf, "%d\n", queue_alignment_offset(disk->queue));
996}
997
998static ssize_t disk_discard_alignment_show(struct device *dev,
999 struct device_attribute *attr,
1000 char *buf)
1001{
1002 struct gendisk *disk = dev_to_disk(dev);
1003
1004 return sprintf(buf, "%d\n", queue_discard_alignment(disk->queue));
1005}
1006
1007static DEVICE_ATTR(range, S_IRUGO, disk_range_show, NULL);
1008static DEVICE_ATTR(ext_range, S_IRUGO, disk_ext_range_show, NULL);
1009static DEVICE_ATTR(removable, S_IRUGO, disk_removable_show, NULL);
1010static DEVICE_ATTR(ro, S_IRUGO, disk_ro_show, NULL);
1011static DEVICE_ATTR(size, S_IRUGO, part_size_show, NULL);
1012static DEVICE_ATTR(alignment_offset, S_IRUGO, disk_alignment_offset_show, NULL);
1013static DEVICE_ATTR(discard_alignment, S_IRUGO, disk_discard_alignment_show,
1014 NULL);
1015static DEVICE_ATTR(capability, S_IRUGO, disk_capability_show, NULL);
1016static DEVICE_ATTR(stat, S_IRUGO, part_stat_show, NULL);
1017static DEVICE_ATTR(inflight, S_IRUGO, part_inflight_show, NULL);
1018static DEVICE_ATTR(badblocks, S_IRUGO | S_IWUSR, disk_badblocks_show,
1019 disk_badblocks_store);
1020#ifdef CONFIG_FAIL_MAKE_REQUEST
1021static struct device_attribute dev_attr_fail =
1022 __ATTR(make-it-fail, S_IRUGO|S_IWUSR, part_fail_show, part_fail_store);
1023#endif
1024#ifdef CONFIG_FAIL_IO_TIMEOUT
1025static struct device_attribute dev_attr_fail_timeout =
1026 __ATTR(io-timeout-fail, S_IRUGO|S_IWUSR, part_timeout_show,
1027 part_timeout_store);
1028#endif
1029
1030static struct attribute *disk_attrs[] = {
1031 &dev_attr_range.attr,
1032 &dev_attr_ext_range.attr,
1033 &dev_attr_removable.attr,
1034 &dev_attr_ro.attr,
1035 &dev_attr_size.attr,
1036 &dev_attr_alignment_offset.attr,
1037 &dev_attr_discard_alignment.attr,
1038 &dev_attr_capability.attr,
1039 &dev_attr_stat.attr,
1040 &dev_attr_inflight.attr,
1041 &dev_attr_badblocks.attr,
1042#ifdef CONFIG_FAIL_MAKE_REQUEST
1043 &dev_attr_fail.attr,
1044#endif
1045#ifdef CONFIG_FAIL_IO_TIMEOUT
1046 &dev_attr_fail_timeout.attr,
1047#endif
1048 NULL
1049};
1050
1051static struct attribute_group disk_attr_group = {
1052 .attrs = disk_attrs,
1053};
1054
1055static const struct attribute_group *disk_attr_groups[] = {
1056 &disk_attr_group,
1057 NULL
1058};
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071static void disk_replace_part_tbl(struct gendisk *disk,
1072 struct disk_part_tbl *new_ptbl)
1073{
1074 struct disk_part_tbl *old_ptbl = disk->part_tbl;
1075
1076 rcu_assign_pointer(disk->part_tbl, new_ptbl);
1077
1078 if (old_ptbl) {
1079 rcu_assign_pointer(old_ptbl->last_lookup, NULL);
1080 kfree_rcu(old_ptbl, rcu_head);
1081 }
1082}
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098int disk_expand_part_tbl(struct gendisk *disk, int partno)
1099{
1100 struct disk_part_tbl *old_ptbl = disk->part_tbl;
1101 struct disk_part_tbl *new_ptbl;
1102 int len = old_ptbl ? old_ptbl->len : 0;
1103 int i, target;
1104 size_t size;
1105
1106
1107
1108
1109
1110 target = partno + 1;
1111 if (target < 0)
1112 return -EINVAL;
1113
1114
1115 if (disk_max_parts(disk) && target > disk_max_parts(disk))
1116 return -EINVAL;
1117
1118 if (target <= len)
1119 return 0;
1120
1121 size = sizeof(*new_ptbl) + target * sizeof(new_ptbl->part[0]);
1122 new_ptbl = kzalloc_node(size, GFP_KERNEL, disk->node_id);
1123 if (!new_ptbl)
1124 return -ENOMEM;
1125
1126 new_ptbl->len = target;
1127
1128 for (i = 0; i < len; i++)
1129 rcu_assign_pointer(new_ptbl->part[i], old_ptbl->part[i]);
1130
1131 disk_replace_part_tbl(disk, new_ptbl);
1132 return 0;
1133}
1134
1135static void disk_release(struct device *dev)
1136{
1137 struct gendisk *disk = dev_to_disk(dev);
1138
1139 blk_free_devt(dev->devt);
1140 disk_release_events(disk);
1141 kfree(disk->random);
1142 disk_replace_part_tbl(disk, NULL);
1143 hd_free_part(&disk->part0);
1144 if (disk->queue)
1145 blk_put_queue(disk->queue);
1146 kfree(disk);
1147}
1148struct class block_class = {
1149 .name = "block",
1150};
1151
1152static char *block_devnode(struct device *dev, umode_t *mode,
1153 kuid_t *uid, kgid_t *gid)
1154{
1155 struct gendisk *disk = dev_to_disk(dev);
1156
1157 if (disk->devnode)
1158 return disk->devnode(disk, mode);
1159 return NULL;
1160}
1161
1162static struct device_type disk_type = {
1163 .name = "disk",
1164 .groups = disk_attr_groups,
1165 .release = disk_release,
1166 .devnode = block_devnode,
1167};
1168
1169#ifdef CONFIG_PROC_FS
1170
1171
1172
1173
1174
1175
1176
1177static int diskstats_show(struct seq_file *seqf, void *v)
1178{
1179 struct gendisk *gp = v;
1180 struct disk_part_iter piter;
1181 struct hd_struct *hd;
1182 char buf[BDEVNAME_SIZE];
1183 int cpu;
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193 disk_part_iter_init(&piter, gp, DISK_PITER_INCL_EMPTY_PART0);
1194 while ((hd = disk_part_iter_next(&piter))) {
1195 cpu = part_stat_lock();
1196 part_round_stats(cpu, hd);
1197 part_stat_unlock();
1198 seq_printf(seqf, "%4d %7d %s %lu %lu %lu "
1199 "%u %lu %lu %lu %u %u %u %u\n",
1200 MAJOR(part_devt(hd)), MINOR(part_devt(hd)),
1201 disk_name(gp, hd->partno, buf),
1202 part_stat_read(hd, ios[READ]),
1203 part_stat_read(hd, merges[READ]),
1204 part_stat_read(hd, sectors[READ]),
1205 jiffies_to_msecs(part_stat_read(hd, ticks[READ])),
1206 part_stat_read(hd, ios[WRITE]),
1207 part_stat_read(hd, merges[WRITE]),
1208 part_stat_read(hd, sectors[WRITE]),
1209 jiffies_to_msecs(part_stat_read(hd, ticks[WRITE])),
1210 part_in_flight(hd),
1211 jiffies_to_msecs(part_stat_read(hd, io_ticks)),
1212 jiffies_to_msecs(part_stat_read(hd, time_in_queue))
1213 );
1214 }
1215 disk_part_iter_exit(&piter);
1216
1217 return 0;
1218}
1219
1220static const struct seq_operations diskstats_op = {
1221 .start = disk_seqf_start,
1222 .next = disk_seqf_next,
1223 .stop = disk_seqf_stop,
1224 .show = diskstats_show
1225};
1226
1227static int diskstats_open(struct inode *inode, struct file *file)
1228{
1229 return seq_open(file, &diskstats_op);
1230}
1231
1232static const struct file_operations proc_diskstats_operations = {
1233 .open = diskstats_open,
1234 .read = seq_read,
1235 .llseek = seq_lseek,
1236 .release = seq_release,
1237};
1238
1239static int __init proc_genhd_init(void)
1240{
1241 proc_create("diskstats", 0, NULL, &proc_diskstats_operations);
1242 proc_create("partitions", 0, NULL, &proc_partitions_operations);
1243 return 0;
1244}
1245module_init(proc_genhd_init);
1246#endif
1247
1248dev_t blk_lookup_devt(const char *name, int partno)
1249{
1250 dev_t devt = MKDEV(0, 0);
1251 struct class_dev_iter iter;
1252 struct device *dev;
1253
1254 class_dev_iter_init(&iter, &block_class, NULL, &disk_type);
1255 while ((dev = class_dev_iter_next(&iter))) {
1256 struct gendisk *disk = dev_to_disk(dev);
1257 struct hd_struct *part;
1258
1259 if (strcmp(dev_name(dev), name))
1260 continue;
1261
1262 if (partno < disk->minors) {
1263
1264
1265
1266 devt = MKDEV(MAJOR(dev->devt),
1267 MINOR(dev->devt) + partno);
1268 break;
1269 }
1270 part = disk_get_part(disk, partno);
1271 if (part) {
1272 devt = part_devt(part);
1273 disk_put_part(part);
1274 break;
1275 }
1276 disk_put_part(part);
1277 }
1278 class_dev_iter_exit(&iter);
1279 return devt;
1280}
1281EXPORT_SYMBOL(blk_lookup_devt);
1282
1283struct gendisk *alloc_disk(int minors)
1284{
1285 return alloc_disk_node(minors, NUMA_NO_NODE);
1286}
1287EXPORT_SYMBOL(alloc_disk);
1288
1289struct gendisk *alloc_disk_node(int minors, int node_id)
1290{
1291 struct gendisk *disk;
1292
1293 disk = kzalloc_node(sizeof(struct gendisk), GFP_KERNEL, node_id);
1294 if (disk) {
1295 if (!init_part_stats(&disk->part0)) {
1296 kfree(disk);
1297 return NULL;
1298 }
1299 disk->node_id = node_id;
1300 if (disk_expand_part_tbl(disk, 0)) {
1301 free_part_stats(&disk->part0);
1302 kfree(disk);
1303 return NULL;
1304 }
1305 disk->part_tbl->part[0] = &disk->part0;
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316 seqcount_init(&disk->part0.nr_sects_seq);
1317 if (hd_ref_init(&disk->part0)) {
1318 hd_free_part(&disk->part0);
1319 kfree(disk);
1320 return NULL;
1321 }
1322
1323 disk->minors = minors;
1324 rand_initialize_disk(disk);
1325 disk_to_dev(disk)->class = &block_class;
1326 disk_to_dev(disk)->type = &disk_type;
1327 device_initialize(disk_to_dev(disk));
1328 }
1329 return disk;
1330}
1331EXPORT_SYMBOL(alloc_disk_node);
1332
1333struct kobject *get_disk(struct gendisk *disk)
1334{
1335 struct module *owner;
1336 struct kobject *kobj;
1337
1338 if (!disk->fops)
1339 return NULL;
1340 owner = disk->fops->owner;
1341 if (owner && !try_module_get(owner))
1342 return NULL;
1343 kobj = kobject_get(&disk_to_dev(disk)->kobj);
1344 if (kobj == NULL) {
1345 module_put(owner);
1346 return NULL;
1347 }
1348 return kobj;
1349
1350}
1351
1352EXPORT_SYMBOL(get_disk);
1353
1354void put_disk(struct gendisk *disk)
1355{
1356 if (disk)
1357 kobject_put(&disk_to_dev(disk)->kobj);
1358}
1359
1360EXPORT_SYMBOL(put_disk);
1361
1362static void set_disk_ro_uevent(struct gendisk *gd, int ro)
1363{
1364 char event[] = "DISK_RO=1";
1365 char *envp[] = { event, NULL };
1366
1367 if (!ro)
1368 event[8] = '0';
1369 kobject_uevent_env(&disk_to_dev(gd)->kobj, KOBJ_CHANGE, envp);
1370}
1371
1372void set_device_ro(struct block_device *bdev, int flag)
1373{
1374 bdev->bd_part->policy = flag;
1375}
1376
1377EXPORT_SYMBOL(set_device_ro);
1378
1379void set_disk_ro(struct gendisk *disk, int flag)
1380{
1381 struct disk_part_iter piter;
1382 struct hd_struct *part;
1383
1384 if (disk->part0.policy != flag) {
1385 set_disk_ro_uevent(disk, flag);
1386 disk->part0.policy = flag;
1387 }
1388
1389 disk_part_iter_init(&piter, disk, DISK_PITER_INCL_EMPTY);
1390 while ((part = disk_part_iter_next(&piter)))
1391 part->policy = flag;
1392 disk_part_iter_exit(&piter);
1393}
1394
1395EXPORT_SYMBOL(set_disk_ro);
1396
1397int bdev_read_only(struct block_device *bdev)
1398{
1399 if (!bdev)
1400 return 0;
1401 return bdev->bd_part->policy;
1402}
1403
1404EXPORT_SYMBOL(bdev_read_only);
1405
1406int invalidate_partition(struct gendisk *disk, int partno)
1407{
1408 int res = 0;
1409 struct block_device *bdev = bdget_disk(disk, partno);
1410 if (bdev) {
1411 fsync_bdev(bdev);
1412 res = __invalidate_device(bdev, true);
1413 bdput(bdev);
1414 }
1415 return res;
1416}
1417
1418EXPORT_SYMBOL(invalidate_partition);
1419
1420
1421
1422
1423struct disk_events {
1424 struct list_head node;
1425 struct gendisk *disk;
1426 spinlock_t lock;
1427
1428 struct mutex block_mutex;
1429 int block;
1430 unsigned int pending;
1431 unsigned int clearing;
1432
1433 long poll_msecs;
1434 struct delayed_work dwork;
1435};
1436
1437static const char *disk_events_strs[] = {
1438 [ilog2(DISK_EVENT_MEDIA_CHANGE)] = "media_change",
1439 [ilog2(DISK_EVENT_EJECT_REQUEST)] = "eject_request",
1440};
1441
1442static char *disk_uevents[] = {
1443 [ilog2(DISK_EVENT_MEDIA_CHANGE)] = "DISK_MEDIA_CHANGE=1",
1444 [ilog2(DISK_EVENT_EJECT_REQUEST)] = "DISK_EJECT_REQUEST=1",
1445};
1446
1447
1448static DEFINE_MUTEX(disk_events_mutex);
1449static LIST_HEAD(disk_events);
1450
1451
1452static unsigned long disk_events_dfl_poll_msecs;
1453
1454static unsigned long disk_events_poll_jiffies(struct gendisk *disk)
1455{
1456 struct disk_events *ev = disk->ev;
1457 long intv_msecs = 0;
1458
1459
1460
1461
1462
1463
1464 if (ev->poll_msecs >= 0)
1465 intv_msecs = ev->poll_msecs;
1466 else if (disk->events & ~disk->async_events)
1467 intv_msecs = disk_events_dfl_poll_msecs;
1468
1469 return msecs_to_jiffies(intv_msecs);
1470}
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487void disk_block_events(struct gendisk *disk)
1488{
1489 struct disk_events *ev = disk->ev;
1490 unsigned long flags;
1491 bool cancel;
1492
1493 if (!ev)
1494 return;
1495
1496
1497
1498
1499
1500 mutex_lock(&ev->block_mutex);
1501
1502 spin_lock_irqsave(&ev->lock, flags);
1503 cancel = !ev->block++;
1504 spin_unlock_irqrestore(&ev->lock, flags);
1505
1506 if (cancel)
1507 cancel_delayed_work_sync(&disk->ev->dwork);
1508
1509 mutex_unlock(&ev->block_mutex);
1510}
1511
1512static void __disk_unblock_events(struct gendisk *disk, bool check_now)
1513{
1514 struct disk_events *ev = disk->ev;
1515 unsigned long intv;
1516 unsigned long flags;
1517
1518 spin_lock_irqsave(&ev->lock, flags);
1519
1520 if (WARN_ON_ONCE(ev->block <= 0))
1521 goto out_unlock;
1522
1523 if (--ev->block)
1524 goto out_unlock;
1525
1526
1527
1528
1529
1530 intv = disk_events_poll_jiffies(disk);
1531 set_timer_slack(&ev->dwork.timer, intv / 4);
1532 if (check_now)
1533 queue_delayed_work(system_freezable_power_efficient_wq,
1534 &ev->dwork, 0);
1535 else if (intv)
1536 queue_delayed_work(system_freezable_power_efficient_wq,
1537 &ev->dwork, intv);
1538out_unlock:
1539 spin_unlock_irqrestore(&ev->lock, flags);
1540}
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552void disk_unblock_events(struct gendisk *disk)
1553{
1554 if (disk->ev)
1555 __disk_unblock_events(disk, false);
1556}
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570void disk_flush_events(struct gendisk *disk, unsigned int mask)
1571{
1572 struct disk_events *ev = disk->ev;
1573
1574 if (!ev)
1575 return;
1576
1577 spin_lock_irq(&ev->lock);
1578 ev->clearing |= mask;
1579 if (!ev->block)
1580 mod_delayed_work(system_freezable_power_efficient_wq,
1581 &ev->dwork, 0);
1582 spin_unlock_irq(&ev->lock);
1583}
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596unsigned int disk_clear_events(struct gendisk *disk, unsigned int mask)
1597{
1598 const struct block_device_operations *bdops = disk->fops;
1599 struct disk_events *ev = disk->ev;
1600 unsigned int pending;
1601 unsigned int clearing = mask;
1602
1603 if (!ev) {
1604
1605 if ((mask & DISK_EVENT_MEDIA_CHANGE) &&
1606 bdops->media_changed && bdops->media_changed(disk))
1607 return DISK_EVENT_MEDIA_CHANGE;
1608 return 0;
1609 }
1610
1611 disk_block_events(disk);
1612
1613
1614
1615
1616
1617
1618 spin_lock_irq(&ev->lock);
1619 clearing |= ev->clearing;
1620 ev->clearing = 0;
1621 spin_unlock_irq(&ev->lock);
1622
1623 disk_check_events(ev, &clearing);
1624
1625
1626
1627
1628 __disk_unblock_events(disk, ev->clearing ? true : false);
1629
1630
1631 spin_lock_irq(&ev->lock);
1632 pending = ev->pending & mask;
1633 ev->pending &= ~mask;
1634 spin_unlock_irq(&ev->lock);
1635 WARN_ON_ONCE(clearing & mask);
1636
1637 return pending;
1638}
1639
1640
1641
1642
1643
1644static void disk_events_workfn(struct work_struct *work)
1645{
1646 struct delayed_work *dwork = to_delayed_work(work);
1647 struct disk_events *ev = container_of(dwork, struct disk_events, dwork);
1648
1649 disk_check_events(ev, &ev->clearing);
1650}
1651
1652static void disk_check_events(struct disk_events *ev,
1653 unsigned int *clearing_ptr)
1654{
1655 struct gendisk *disk = ev->disk;
1656 char *envp[ARRAY_SIZE(disk_uevents) + 1] = { };
1657 unsigned int clearing = *clearing_ptr;
1658 unsigned int events;
1659 unsigned long intv;
1660 int nr_events = 0, i;
1661
1662
1663 events = disk->fops->check_events(disk, clearing);
1664
1665
1666 spin_lock_irq(&ev->lock);
1667
1668 events &= ~ev->pending;
1669 ev->pending |= events;
1670 *clearing_ptr &= ~clearing;
1671
1672 intv = disk_events_poll_jiffies(disk);
1673 if (!ev->block && intv)
1674 queue_delayed_work(system_freezable_power_efficient_wq,
1675 &ev->dwork, intv);
1676
1677 spin_unlock_irq(&ev->lock);
1678
1679
1680
1681
1682
1683
1684 for (i = 0; i < ARRAY_SIZE(disk_uevents); i++)
1685 if (events & disk->events & (1 << i))
1686 envp[nr_events++] = disk_uevents[i];
1687
1688 if (nr_events)
1689 kobject_uevent_env(&disk_to_dev(disk)->kobj, KOBJ_CHANGE, envp);
1690}
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700static ssize_t __disk_events_show(unsigned int events, char *buf)
1701{
1702 const char *delim = "";
1703 ssize_t pos = 0;
1704 int i;
1705
1706 for (i = 0; i < ARRAY_SIZE(disk_events_strs); i++)
1707 if (events & (1 << i)) {
1708 pos += sprintf(buf + pos, "%s%s",
1709 delim, disk_events_strs[i]);
1710 delim = " ";
1711 }
1712 if (pos)
1713 pos += sprintf(buf + pos, "\n");
1714 return pos;
1715}
1716
1717static ssize_t disk_events_show(struct device *dev,
1718 struct device_attribute *attr, char *buf)
1719{
1720 struct gendisk *disk = dev_to_disk(dev);
1721
1722 return __disk_events_show(disk->events, buf);
1723}
1724
1725static ssize_t disk_events_async_show(struct device *dev,
1726 struct device_attribute *attr, char *buf)
1727{
1728 struct gendisk *disk = dev_to_disk(dev);
1729
1730 return __disk_events_show(disk->async_events, buf);
1731}
1732
1733static ssize_t disk_events_poll_msecs_show(struct device *dev,
1734 struct device_attribute *attr,
1735 char *buf)
1736{
1737 struct gendisk *disk = dev_to_disk(dev);
1738
1739 return sprintf(buf, "%ld\n", disk->ev->poll_msecs);
1740}
1741
1742static ssize_t disk_events_poll_msecs_store(struct device *dev,
1743 struct device_attribute *attr,
1744 const char *buf, size_t count)
1745{
1746 struct gendisk *disk = dev_to_disk(dev);
1747 long intv;
1748
1749 if (!count || !sscanf(buf, "%ld", &intv))
1750 return -EINVAL;
1751
1752 if (intv < 0 && intv != -1)
1753 return -EINVAL;
1754
1755 disk_block_events(disk);
1756 disk->ev->poll_msecs = intv;
1757 __disk_unblock_events(disk, true);
1758
1759 return count;
1760}
1761
1762static const DEVICE_ATTR(events, S_IRUGO, disk_events_show, NULL);
1763static const DEVICE_ATTR(events_async, S_IRUGO, disk_events_async_show, NULL);
1764static const DEVICE_ATTR(events_poll_msecs, S_IRUGO|S_IWUSR,
1765 disk_events_poll_msecs_show,
1766 disk_events_poll_msecs_store);
1767
1768static const struct attribute *disk_events_attrs[] = {
1769 &dev_attr_events.attr,
1770 &dev_attr_events_async.attr,
1771 &dev_attr_events_poll_msecs.attr,
1772 NULL,
1773};
1774
1775
1776
1777
1778
1779
1780
1781static int disk_events_set_dfl_poll_msecs(const char *val,
1782 const struct kernel_param *kp)
1783{
1784 struct disk_events *ev;
1785 int ret;
1786
1787 ret = param_set_ulong(val, kp);
1788 if (ret < 0)
1789 return ret;
1790
1791 mutex_lock(&disk_events_mutex);
1792
1793 list_for_each_entry(ev, &disk_events, node)
1794 disk_flush_events(ev->disk, 0);
1795
1796 mutex_unlock(&disk_events_mutex);
1797
1798 return 0;
1799}
1800
1801static const struct kernel_param_ops disk_events_dfl_poll_msecs_param_ops = {
1802 .set = disk_events_set_dfl_poll_msecs,
1803 .get = param_get_ulong,
1804};
1805
1806#undef MODULE_PARAM_PREFIX
1807#define MODULE_PARAM_PREFIX "block."
1808
1809module_param_cb(events_dfl_poll_msecs, &disk_events_dfl_poll_msecs_param_ops,
1810 &disk_events_dfl_poll_msecs, 0644);
1811
1812
1813
1814
1815static void disk_alloc_events(struct gendisk *disk)
1816{
1817 struct disk_events *ev;
1818
1819 if (!disk->fops->check_events)
1820 return;
1821
1822 ev = kzalloc(sizeof(*ev), GFP_KERNEL);
1823 if (!ev) {
1824 pr_warn("%s: failed to initialize events\n", disk->disk_name);
1825 return;
1826 }
1827
1828 INIT_LIST_HEAD(&ev->node);
1829 ev->disk = disk;
1830 spin_lock_init(&ev->lock);
1831 mutex_init(&ev->block_mutex);
1832 ev->block = 1;
1833 ev->poll_msecs = -1;
1834 INIT_DELAYED_WORK(&ev->dwork, disk_events_workfn);
1835
1836 disk->ev = ev;
1837}
1838
1839static void disk_add_events(struct gendisk *disk)
1840{
1841 if (!disk->ev)
1842 return;
1843
1844
1845 if (sysfs_create_files(&disk_to_dev(disk)->kobj, disk_events_attrs) < 0)
1846 pr_warn("%s: failed to create sysfs files for events\n",
1847 disk->disk_name);
1848
1849 mutex_lock(&disk_events_mutex);
1850 list_add_tail(&disk->ev->node, &disk_events);
1851 mutex_unlock(&disk_events_mutex);
1852
1853
1854
1855
1856
1857 __disk_unblock_events(disk, true);
1858}
1859
1860static void disk_del_events(struct gendisk *disk)
1861{
1862 if (!disk->ev)
1863 return;
1864
1865 disk_block_events(disk);
1866
1867 mutex_lock(&disk_events_mutex);
1868 list_del_init(&disk->ev->node);
1869 mutex_unlock(&disk_events_mutex);
1870
1871 sysfs_remove_files(&disk_to_dev(disk)->kobj, disk_events_attrs);
1872}
1873
1874static void disk_release_events(struct gendisk *disk)
1875{
1876
1877 WARN_ON_ONCE(disk->ev && disk->ev->block != 1);
1878 kfree(disk->ev);
1879}
1880