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
202
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 device *parent, 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 = parent;
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
584
585void device_add_disk(struct device *parent, struct gendisk *disk)
586{
587 struct backing_dev_info *bdi;
588 dev_t devt;
589 int retval;
590
591
592
593
594
595 WARN_ON(disk->minors && !(disk->major || disk->first_minor));
596 WARN_ON(!disk->minors && !(disk->flags & GENHD_FL_EXT_DEVT));
597
598 disk->flags |= GENHD_FL_UP;
599
600 retval = blk_alloc_devt(&disk->part0, &devt);
601 if (retval) {
602 WARN_ON(1);
603 return;
604 }
605 disk_to_dev(disk)->devt = devt;
606
607
608
609
610 disk->major = MAJOR(devt);
611 disk->first_minor = MINOR(devt);
612
613 disk_alloc_events(disk);
614
615
616 bdi = &disk->queue->backing_dev_info;
617 bdi_register_owner(bdi, disk_to_dev(disk));
618
619 blk_register_region(disk_devt(disk), disk->minors, NULL,
620 exact_match, exact_lock, disk);
621 register_disk(parent, disk);
622 blk_register_queue(disk);
623
624
625
626
627
628 WARN_ON_ONCE(!blk_get_queue(disk->queue));
629
630 retval = sysfs_create_link(&disk_to_dev(disk)->kobj, &bdi->dev->kobj,
631 "bdi");
632 WARN_ON(retval);
633
634 disk_add_events(disk);
635 blk_integrity_add(disk);
636}
637EXPORT_SYMBOL(device_add_disk);
638
639void del_gendisk(struct gendisk *disk)
640{
641 struct disk_part_iter piter;
642 struct hd_struct *part;
643
644 blk_integrity_del(disk);
645 disk_del_events(disk);
646
647
648 disk_part_iter_init(&piter, disk,
649 DISK_PITER_INCL_EMPTY | DISK_PITER_REVERSE);
650 while ((part = disk_part_iter_next(&piter))) {
651 invalidate_partition(disk, part->partno);
652 delete_partition(disk, part->partno);
653 }
654 disk_part_iter_exit(&piter);
655
656 invalidate_partition(disk, 0);
657 set_capacity(disk, 0);
658 disk->flags &= ~GENHD_FL_UP;
659
660 sysfs_remove_link(&disk_to_dev(disk)->kobj, "bdi");
661 blk_unregister_queue(disk);
662 blk_unregister_region(disk_devt(disk), disk->minors);
663
664 part_stat_set_all(&disk->part0, 0);
665 disk->part0.stamp = 0;
666
667 kobject_put(disk->part0.holder_dir);
668 kobject_put(disk->slave_dir);
669 if (!sysfs_deprecated)
670 sysfs_remove_link(block_depr, dev_name(disk_to_dev(disk)));
671 pm_runtime_set_memalloc_noio(disk_to_dev(disk), false);
672 device_del(disk_to_dev(disk));
673}
674EXPORT_SYMBOL(del_gendisk);
675
676
677static ssize_t disk_badblocks_show(struct device *dev,
678 struct device_attribute *attr,
679 char *page)
680{
681 struct gendisk *disk = dev_to_disk(dev);
682
683 if (!disk->bb)
684 return sprintf(page, "\n");
685
686 return badblocks_show(disk->bb, page, 0);
687}
688
689static ssize_t disk_badblocks_store(struct device *dev,
690 struct device_attribute *attr,
691 const char *page, size_t len)
692{
693 struct gendisk *disk = dev_to_disk(dev);
694
695 if (!disk->bb)
696 return -ENXIO;
697
698 return badblocks_store(disk->bb, page, len, 0);
699}
700
701
702
703
704
705
706
707
708
709struct gendisk *get_gendisk(dev_t devt, int *partno)
710{
711 struct gendisk *disk = NULL;
712
713 if (MAJOR(devt) != BLOCK_EXT_MAJOR) {
714 struct kobject *kobj;
715
716 kobj = kobj_lookup(bdev_map, devt, partno);
717 if (kobj)
718 disk = dev_to_disk(kobj_to_dev(kobj));
719 } else {
720 struct hd_struct *part;
721
722 spin_lock_bh(&ext_devt_lock);
723 part = idr_find(&ext_devt_idr, blk_mangle_minor(MINOR(devt)));
724 if (part && get_disk(part_to_disk(part))) {
725 *partno = part->partno;
726 disk = part_to_disk(part);
727 }
728 spin_unlock_bh(&ext_devt_lock);
729 }
730
731 return disk;
732}
733EXPORT_SYMBOL(get_gendisk);
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748struct block_device *bdget_disk(struct gendisk *disk, int partno)
749{
750 struct hd_struct *part;
751 struct block_device *bdev = NULL;
752
753 part = disk_get_part(disk, partno);
754 if (part)
755 bdev = bdget(part_devt(part));
756 disk_put_part(part);
757
758 return bdev;
759}
760EXPORT_SYMBOL(bdget_disk);
761
762
763
764
765
766
767void __init printk_all_partitions(void)
768{
769 struct class_dev_iter iter;
770 struct device *dev;
771
772 class_dev_iter_init(&iter, &block_class, NULL, &disk_type);
773 while ((dev = class_dev_iter_next(&iter))) {
774 struct gendisk *disk = dev_to_disk(dev);
775 struct disk_part_iter piter;
776 struct hd_struct *part;
777 char name_buf[BDEVNAME_SIZE];
778 char devt_buf[BDEVT_SIZE];
779
780
781
782
783
784 if (get_capacity(disk) == 0 ||
785 (disk->flags & GENHD_FL_SUPPRESS_PARTITION_INFO))
786 continue;
787
788
789
790
791
792
793 disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0);
794 while ((part = disk_part_iter_next(&piter))) {
795 bool is_part0 = part == &disk->part0;
796
797 printk("%s%s %10llu %s %s", is_part0 ? "" : " ",
798 bdevt_str(part_devt(part), devt_buf),
799 (unsigned long long)part_nr_sects_read(part) >> 1
800 , disk_name(disk, part->partno, name_buf),
801 part->info ? part->info->uuid : "");
802 if (is_part0) {
803 if (dev->parent && dev->parent->driver)
804 printk(" driver: %s\n",
805 dev->parent->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 seqf->private = NULL;
860 }
861}
862
863static void *show_partition_start(struct seq_file *seqf, loff_t *pos)
864{
865 void *p;
866
867 p = disk_seqf_start(seqf, pos);
868 if (!IS_ERR_OR_NULL(p) && !*pos)
869 seq_puts(seqf, "major minor #blocks name\n\n");
870 return p;
871}
872
873static int show_partition(struct seq_file *seqf, void *v)
874{
875 struct gendisk *sgp = v;
876 struct disk_part_iter piter;
877 struct hd_struct *part;
878 char buf[BDEVNAME_SIZE];
879
880
881 if (!get_capacity(sgp) || (!disk_max_parts(sgp) &&
882 (sgp->flags & GENHD_FL_REMOVABLE)))
883 return 0;
884 if (sgp->flags & GENHD_FL_SUPPRESS_PARTITION_INFO)
885 return 0;
886
887
888 disk_part_iter_init(&piter, sgp, DISK_PITER_INCL_PART0);
889 while ((part = disk_part_iter_next(&piter)))
890 seq_printf(seqf, "%4d %7d %10llu %s\n",
891 MAJOR(part_devt(part)), MINOR(part_devt(part)),
892 (unsigned long long)part_nr_sects_read(part) >> 1,
893 disk_name(sgp, part->partno, buf));
894 disk_part_iter_exit(&piter);
895
896 return 0;
897}
898
899static const struct seq_operations partitions_op = {
900 .start = show_partition_start,
901 .next = disk_seqf_next,
902 .stop = disk_seqf_stop,
903 .show = show_partition
904};
905
906static int partitions_open(struct inode *inode, struct file *file)
907{
908 return seq_open(file, &partitions_op);
909}
910
911static const struct file_operations proc_partitions_operations = {
912 .open = partitions_open,
913 .read = seq_read,
914 .llseek = seq_lseek,
915 .release = seq_release,
916};
917#endif
918
919
920static struct kobject *base_probe(dev_t devt, int *partno, void *data)
921{
922 if (request_module("block-major-%d-%d", MAJOR(devt), MINOR(devt)) > 0)
923
924 request_module("block-major-%d", MAJOR(devt));
925 return NULL;
926}
927
928static int __init genhd_device_init(void)
929{
930 int error;
931
932 block_class.dev_kobj = sysfs_dev_block_kobj;
933 error = class_register(&block_class);
934 if (unlikely(error))
935 return error;
936 bdev_map = kobj_map_init(base_probe, &block_class_lock);
937 blk_dev_init();
938
939 register_blkdev(BLOCK_EXT_MAJOR, "blkext");
940
941
942 if (!sysfs_deprecated)
943 block_depr = kobject_create_and_add("block", NULL);
944 return 0;
945}
946
947subsys_initcall(genhd_device_init);
948
949static ssize_t disk_range_show(struct device *dev,
950 struct device_attribute *attr, char *buf)
951{
952 struct gendisk *disk = dev_to_disk(dev);
953
954 return sprintf(buf, "%d\n", disk->minors);
955}
956
957static ssize_t disk_ext_range_show(struct device *dev,
958 struct device_attribute *attr, char *buf)
959{
960 struct gendisk *disk = dev_to_disk(dev);
961
962 return sprintf(buf, "%d\n", disk_max_parts(disk));
963}
964
965static ssize_t disk_removable_show(struct device *dev,
966 struct device_attribute *attr, char *buf)
967{
968 struct gendisk *disk = dev_to_disk(dev);
969
970 return sprintf(buf, "%d\n",
971 (disk->flags & GENHD_FL_REMOVABLE ? 1 : 0));
972}
973
974static ssize_t disk_ro_show(struct device *dev,
975 struct device_attribute *attr, char *buf)
976{
977 struct gendisk *disk = dev_to_disk(dev);
978
979 return sprintf(buf, "%d\n", get_disk_ro(disk) ? 1 : 0);
980}
981
982static ssize_t disk_capability_show(struct device *dev,
983 struct device_attribute *attr, char *buf)
984{
985 struct gendisk *disk = dev_to_disk(dev);
986
987 return sprintf(buf, "%x\n", disk->flags);
988}
989
990static ssize_t disk_alignment_offset_show(struct device *dev,
991 struct device_attribute *attr,
992 char *buf)
993{
994 struct gendisk *disk = dev_to_disk(dev);
995
996 return sprintf(buf, "%d\n", queue_alignment_offset(disk->queue));
997}
998
999static ssize_t disk_discard_alignment_show(struct device *dev,
1000 struct device_attribute *attr,
1001 char *buf)
1002{
1003 struct gendisk *disk = dev_to_disk(dev);
1004
1005 return sprintf(buf, "%d\n", queue_discard_alignment(disk->queue));
1006}
1007
1008static DEVICE_ATTR(range, S_IRUGO, disk_range_show, NULL);
1009static DEVICE_ATTR(ext_range, S_IRUGO, disk_ext_range_show, NULL);
1010static DEVICE_ATTR(removable, S_IRUGO, disk_removable_show, NULL);
1011static DEVICE_ATTR(ro, S_IRUGO, disk_ro_show, NULL);
1012static DEVICE_ATTR(size, S_IRUGO, part_size_show, NULL);
1013static DEVICE_ATTR(alignment_offset, S_IRUGO, disk_alignment_offset_show, NULL);
1014static DEVICE_ATTR(discard_alignment, S_IRUGO, disk_discard_alignment_show,
1015 NULL);
1016static DEVICE_ATTR(capability, S_IRUGO, disk_capability_show, NULL);
1017static DEVICE_ATTR(stat, S_IRUGO, part_stat_show, NULL);
1018static DEVICE_ATTR(inflight, S_IRUGO, part_inflight_show, NULL);
1019static DEVICE_ATTR(badblocks, S_IRUGO | S_IWUSR, disk_badblocks_show,
1020 disk_badblocks_store);
1021#ifdef CONFIG_FAIL_MAKE_REQUEST
1022static struct device_attribute dev_attr_fail =
1023 __ATTR(make-it-fail, S_IRUGO|S_IWUSR, part_fail_show, part_fail_store);
1024#endif
1025#ifdef CONFIG_FAIL_IO_TIMEOUT
1026static struct device_attribute dev_attr_fail_timeout =
1027 __ATTR(io-timeout-fail, S_IRUGO|S_IWUSR, part_timeout_show,
1028 part_timeout_store);
1029#endif
1030
1031static struct attribute *disk_attrs[] = {
1032 &dev_attr_range.attr,
1033 &dev_attr_ext_range.attr,
1034 &dev_attr_removable.attr,
1035 &dev_attr_ro.attr,
1036 &dev_attr_size.attr,
1037 &dev_attr_alignment_offset.attr,
1038 &dev_attr_discard_alignment.attr,
1039 &dev_attr_capability.attr,
1040 &dev_attr_stat.attr,
1041 &dev_attr_inflight.attr,
1042 &dev_attr_badblocks.attr,
1043#ifdef CONFIG_FAIL_MAKE_REQUEST
1044 &dev_attr_fail.attr,
1045#endif
1046#ifdef CONFIG_FAIL_IO_TIMEOUT
1047 &dev_attr_fail_timeout.attr,
1048#endif
1049 NULL
1050};
1051
1052static struct attribute_group disk_attr_group = {
1053 .attrs = disk_attrs,
1054};
1055
1056static const struct attribute_group *disk_attr_groups[] = {
1057 &disk_attr_group,
1058 NULL
1059};
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072static void disk_replace_part_tbl(struct gendisk *disk,
1073 struct disk_part_tbl *new_ptbl)
1074{
1075 struct disk_part_tbl *old_ptbl = disk->part_tbl;
1076
1077 rcu_assign_pointer(disk->part_tbl, new_ptbl);
1078
1079 if (old_ptbl) {
1080 rcu_assign_pointer(old_ptbl->last_lookup, NULL);
1081 kfree_rcu(old_ptbl, rcu_head);
1082 }
1083}
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099int disk_expand_part_tbl(struct gendisk *disk, int partno)
1100{
1101 struct disk_part_tbl *old_ptbl = disk->part_tbl;
1102 struct disk_part_tbl *new_ptbl;
1103 int len = old_ptbl ? old_ptbl->len : 0;
1104 int i, target;
1105 size_t size;
1106
1107
1108
1109
1110
1111 target = partno + 1;
1112 if (target < 0)
1113 return -EINVAL;
1114
1115
1116 if (disk_max_parts(disk) && target > disk_max_parts(disk))
1117 return -EINVAL;
1118
1119 if (target <= len)
1120 return 0;
1121
1122 size = sizeof(*new_ptbl) + target * sizeof(new_ptbl->part[0]);
1123 new_ptbl = kzalloc_node(size, GFP_KERNEL, disk->node_id);
1124 if (!new_ptbl)
1125 return -ENOMEM;
1126
1127 new_ptbl->len = target;
1128
1129 for (i = 0; i < len; i++)
1130 rcu_assign_pointer(new_ptbl->part[i], old_ptbl->part[i]);
1131
1132 disk_replace_part_tbl(disk, new_ptbl);
1133 return 0;
1134}
1135
1136static void disk_release(struct device *dev)
1137{
1138 struct gendisk *disk = dev_to_disk(dev);
1139
1140 blk_free_devt(dev->devt);
1141 disk_release_events(disk);
1142 kfree(disk->random);
1143 disk_replace_part_tbl(disk, NULL);
1144 hd_free_part(&disk->part0);
1145 if (disk->queue)
1146 blk_put_queue(disk->queue);
1147 kfree(disk);
1148}
1149struct class block_class = {
1150 .name = "block",
1151};
1152
1153static char *block_devnode(struct device *dev, umode_t *mode,
1154 kuid_t *uid, kgid_t *gid)
1155{
1156 struct gendisk *disk = dev_to_disk(dev);
1157
1158 if (disk->devnode)
1159 return disk->devnode(disk, mode);
1160 return NULL;
1161}
1162
1163static struct device_type disk_type = {
1164 .name = "disk",
1165 .groups = disk_attr_groups,
1166 .release = disk_release,
1167 .devnode = block_devnode,
1168};
1169
1170#ifdef CONFIG_PROC_FS
1171
1172
1173
1174
1175
1176
1177
1178static int diskstats_show(struct seq_file *seqf, void *v)
1179{
1180 struct gendisk *gp = v;
1181 struct disk_part_iter piter;
1182 struct hd_struct *hd;
1183 char buf[BDEVNAME_SIZE];
1184 int cpu;
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194 disk_part_iter_init(&piter, gp, DISK_PITER_INCL_EMPTY_PART0);
1195 while ((hd = disk_part_iter_next(&piter))) {
1196 cpu = part_stat_lock();
1197 part_round_stats(cpu, hd);
1198 part_stat_unlock();
1199 seq_printf(seqf, "%4d %7d %s %lu %lu %lu "
1200 "%u %lu %lu %lu %u %u %u %u\n",
1201 MAJOR(part_devt(hd)), MINOR(part_devt(hd)),
1202 disk_name(gp, hd->partno, buf),
1203 part_stat_read(hd, ios[READ]),
1204 part_stat_read(hd, merges[READ]),
1205 part_stat_read(hd, sectors[READ]),
1206 jiffies_to_msecs(part_stat_read(hd, ticks[READ])),
1207 part_stat_read(hd, ios[WRITE]),
1208 part_stat_read(hd, merges[WRITE]),
1209 part_stat_read(hd, sectors[WRITE]),
1210 jiffies_to_msecs(part_stat_read(hd, ticks[WRITE])),
1211 part_in_flight(hd),
1212 jiffies_to_msecs(part_stat_read(hd, io_ticks)),
1213 jiffies_to_msecs(part_stat_read(hd, time_in_queue))
1214 );
1215 }
1216 disk_part_iter_exit(&piter);
1217
1218 return 0;
1219}
1220
1221static const struct seq_operations diskstats_op = {
1222 .start = disk_seqf_start,
1223 .next = disk_seqf_next,
1224 .stop = disk_seqf_stop,
1225 .show = diskstats_show
1226};
1227
1228static int diskstats_open(struct inode *inode, struct file *file)
1229{
1230 return seq_open(file, &diskstats_op);
1231}
1232
1233static const struct file_operations proc_diskstats_operations = {
1234 .open = diskstats_open,
1235 .read = seq_read,
1236 .llseek = seq_lseek,
1237 .release = seq_release,
1238};
1239
1240static int __init proc_genhd_init(void)
1241{
1242 proc_create("diskstats", 0, NULL, &proc_diskstats_operations);
1243 proc_create("partitions", 0, NULL, &proc_partitions_operations);
1244 return 0;
1245}
1246module_init(proc_genhd_init);
1247#endif
1248
1249dev_t blk_lookup_devt(const char *name, int partno)
1250{
1251 dev_t devt = MKDEV(0, 0);
1252 struct class_dev_iter iter;
1253 struct device *dev;
1254
1255 class_dev_iter_init(&iter, &block_class, NULL, &disk_type);
1256 while ((dev = class_dev_iter_next(&iter))) {
1257 struct gendisk *disk = dev_to_disk(dev);
1258 struct hd_struct *part;
1259
1260 if (strcmp(dev_name(dev), name))
1261 continue;
1262
1263 if (partno < disk->minors) {
1264
1265
1266
1267 devt = MKDEV(MAJOR(dev->devt),
1268 MINOR(dev->devt) + partno);
1269 break;
1270 }
1271 part = disk_get_part(disk, partno);
1272 if (part) {
1273 devt = part_devt(part);
1274 disk_put_part(part);
1275 break;
1276 }
1277 disk_put_part(part);
1278 }
1279 class_dev_iter_exit(&iter);
1280 return devt;
1281}
1282EXPORT_SYMBOL(blk_lookup_devt);
1283
1284struct gendisk *alloc_disk(int minors)
1285{
1286 return alloc_disk_node(minors, NUMA_NO_NODE);
1287}
1288EXPORT_SYMBOL(alloc_disk);
1289
1290struct gendisk *alloc_disk_node(int minors, int node_id)
1291{
1292 struct gendisk *disk;
1293
1294 disk = kzalloc_node(sizeof(struct gendisk), GFP_KERNEL, node_id);
1295 if (disk) {
1296 if (!init_part_stats(&disk->part0)) {
1297 kfree(disk);
1298 return NULL;
1299 }
1300 disk->node_id = node_id;
1301 if (disk_expand_part_tbl(disk, 0)) {
1302 free_part_stats(&disk->part0);
1303 kfree(disk);
1304 return NULL;
1305 }
1306 disk->part_tbl->part[0] = &disk->part0;
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317 seqcount_init(&disk->part0.nr_sects_seq);
1318 if (hd_ref_init(&disk->part0)) {
1319 hd_free_part(&disk->part0);
1320 kfree(disk);
1321 return NULL;
1322 }
1323
1324 disk->minors = minors;
1325 rand_initialize_disk(disk);
1326 disk_to_dev(disk)->class = &block_class;
1327 disk_to_dev(disk)->type = &disk_type;
1328 device_initialize(disk_to_dev(disk));
1329 }
1330 return disk;
1331}
1332EXPORT_SYMBOL(alloc_disk_node);
1333
1334struct kobject *get_disk(struct gendisk *disk)
1335{
1336 struct module *owner;
1337 struct kobject *kobj;
1338
1339 if (!disk->fops)
1340 return NULL;
1341 owner = disk->fops->owner;
1342 if (owner && !try_module_get(owner))
1343 return NULL;
1344 kobj = kobject_get(&disk_to_dev(disk)->kobj);
1345 if (kobj == NULL) {
1346 module_put(owner);
1347 return NULL;
1348 }
1349 return kobj;
1350
1351}
1352
1353EXPORT_SYMBOL(get_disk);
1354
1355void put_disk(struct gendisk *disk)
1356{
1357 if (disk)
1358 kobject_put(&disk_to_dev(disk)->kobj);
1359}
1360
1361EXPORT_SYMBOL(put_disk);
1362
1363static void set_disk_ro_uevent(struct gendisk *gd, int ro)
1364{
1365 char event[] = "DISK_RO=1";
1366 char *envp[] = { event, NULL };
1367
1368 if (!ro)
1369 event[8] = '0';
1370 kobject_uevent_env(&disk_to_dev(gd)->kobj, KOBJ_CHANGE, envp);
1371}
1372
1373void set_device_ro(struct block_device *bdev, int flag)
1374{
1375 bdev->bd_part->policy = flag;
1376}
1377
1378EXPORT_SYMBOL(set_device_ro);
1379
1380void set_disk_ro(struct gendisk *disk, int flag)
1381{
1382 struct disk_part_iter piter;
1383 struct hd_struct *part;
1384
1385 if (disk->part0.policy != flag) {
1386 set_disk_ro_uevent(disk, flag);
1387 disk->part0.policy = flag;
1388 }
1389
1390 disk_part_iter_init(&piter, disk, DISK_PITER_INCL_EMPTY);
1391 while ((part = disk_part_iter_next(&piter)))
1392 part->policy = flag;
1393 disk_part_iter_exit(&piter);
1394}
1395
1396EXPORT_SYMBOL(set_disk_ro);
1397
1398int bdev_read_only(struct block_device *bdev)
1399{
1400 if (!bdev)
1401 return 0;
1402 return bdev->bd_part->policy;
1403}
1404
1405EXPORT_SYMBOL(bdev_read_only);
1406
1407int invalidate_partition(struct gendisk *disk, int partno)
1408{
1409 int res = 0;
1410 struct block_device *bdev = bdget_disk(disk, partno);
1411 if (bdev) {
1412 fsync_bdev(bdev);
1413 res = __invalidate_device(bdev, true);
1414 bdput(bdev);
1415 }
1416 return res;
1417}
1418
1419EXPORT_SYMBOL(invalidate_partition);
1420
1421
1422
1423
1424struct disk_events {
1425 struct list_head node;
1426 struct gendisk *disk;
1427 spinlock_t lock;
1428
1429 struct mutex block_mutex;
1430 int block;
1431 unsigned int pending;
1432 unsigned int clearing;
1433
1434 long poll_msecs;
1435 struct delayed_work dwork;
1436};
1437
1438static const char *disk_events_strs[] = {
1439 [ilog2(DISK_EVENT_MEDIA_CHANGE)] = "media_change",
1440 [ilog2(DISK_EVENT_EJECT_REQUEST)] = "eject_request",
1441};
1442
1443static char *disk_uevents[] = {
1444 [ilog2(DISK_EVENT_MEDIA_CHANGE)] = "DISK_MEDIA_CHANGE=1",
1445 [ilog2(DISK_EVENT_EJECT_REQUEST)] = "DISK_EJECT_REQUEST=1",
1446};
1447
1448
1449static DEFINE_MUTEX(disk_events_mutex);
1450static LIST_HEAD(disk_events);
1451
1452
1453static unsigned long disk_events_dfl_poll_msecs;
1454
1455static unsigned long disk_events_poll_jiffies(struct gendisk *disk)
1456{
1457 struct disk_events *ev = disk->ev;
1458 long intv_msecs = 0;
1459
1460
1461
1462
1463
1464
1465 if (ev->poll_msecs >= 0)
1466 intv_msecs = ev->poll_msecs;
1467 else if (disk->events & ~disk->async_events)
1468 intv_msecs = disk_events_dfl_poll_msecs;
1469
1470 return msecs_to_jiffies(intv_msecs);
1471}
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488void disk_block_events(struct gendisk *disk)
1489{
1490 struct disk_events *ev = disk->ev;
1491 unsigned long flags;
1492 bool cancel;
1493
1494 if (!ev)
1495 return;
1496
1497
1498
1499
1500
1501 mutex_lock(&ev->block_mutex);
1502
1503 spin_lock_irqsave(&ev->lock, flags);
1504 cancel = !ev->block++;
1505 spin_unlock_irqrestore(&ev->lock, flags);
1506
1507 if (cancel)
1508 cancel_delayed_work_sync(&disk->ev->dwork);
1509
1510 mutex_unlock(&ev->block_mutex);
1511}
1512
1513static void __disk_unblock_events(struct gendisk *disk, bool check_now)
1514{
1515 struct disk_events *ev = disk->ev;
1516 unsigned long intv;
1517 unsigned long flags;
1518
1519 spin_lock_irqsave(&ev->lock, flags);
1520
1521 if (WARN_ON_ONCE(ev->block <= 0))
1522 goto out_unlock;
1523
1524 if (--ev->block)
1525 goto out_unlock;
1526
1527 intv = disk_events_poll_jiffies(disk);
1528 if (check_now)
1529 queue_delayed_work(system_freezable_power_efficient_wq,
1530 &ev->dwork, 0);
1531 else if (intv)
1532 queue_delayed_work(system_freezable_power_efficient_wq,
1533 &ev->dwork, intv);
1534out_unlock:
1535 spin_unlock_irqrestore(&ev->lock, flags);
1536}
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548void disk_unblock_events(struct gendisk *disk)
1549{
1550 if (disk->ev)
1551 __disk_unblock_events(disk, false);
1552}
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566void disk_flush_events(struct gendisk *disk, unsigned int mask)
1567{
1568 struct disk_events *ev = disk->ev;
1569
1570 if (!ev)
1571 return;
1572
1573 spin_lock_irq(&ev->lock);
1574 ev->clearing |= mask;
1575 if (!ev->block)
1576 mod_delayed_work(system_freezable_power_efficient_wq,
1577 &ev->dwork, 0);
1578 spin_unlock_irq(&ev->lock);
1579}
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592unsigned int disk_clear_events(struct gendisk *disk, unsigned int mask)
1593{
1594 const struct block_device_operations *bdops = disk->fops;
1595 struct disk_events *ev = disk->ev;
1596 unsigned int pending;
1597 unsigned int clearing = mask;
1598
1599 if (!ev) {
1600
1601 if ((mask & DISK_EVENT_MEDIA_CHANGE) &&
1602 bdops->media_changed && bdops->media_changed(disk))
1603 return DISK_EVENT_MEDIA_CHANGE;
1604 return 0;
1605 }
1606
1607 disk_block_events(disk);
1608
1609
1610
1611
1612
1613
1614 spin_lock_irq(&ev->lock);
1615 clearing |= ev->clearing;
1616 ev->clearing = 0;
1617 spin_unlock_irq(&ev->lock);
1618
1619 disk_check_events(ev, &clearing);
1620
1621
1622
1623
1624 __disk_unblock_events(disk, ev->clearing ? true : false);
1625
1626
1627 spin_lock_irq(&ev->lock);
1628 pending = ev->pending & mask;
1629 ev->pending &= ~mask;
1630 spin_unlock_irq(&ev->lock);
1631 WARN_ON_ONCE(clearing & mask);
1632
1633 return pending;
1634}
1635
1636
1637
1638
1639
1640static void disk_events_workfn(struct work_struct *work)
1641{
1642 struct delayed_work *dwork = to_delayed_work(work);
1643 struct disk_events *ev = container_of(dwork, struct disk_events, dwork);
1644
1645 disk_check_events(ev, &ev->clearing);
1646}
1647
1648static void disk_check_events(struct disk_events *ev,
1649 unsigned int *clearing_ptr)
1650{
1651 struct gendisk *disk = ev->disk;
1652 char *envp[ARRAY_SIZE(disk_uevents) + 1] = { };
1653 unsigned int clearing = *clearing_ptr;
1654 unsigned int events;
1655 unsigned long intv;
1656 int nr_events = 0, i;
1657
1658
1659 events = disk->fops->check_events(disk, clearing);
1660
1661
1662 spin_lock_irq(&ev->lock);
1663
1664 events &= ~ev->pending;
1665 ev->pending |= events;
1666 *clearing_ptr &= ~clearing;
1667
1668 intv = disk_events_poll_jiffies(disk);
1669 if (!ev->block && intv)
1670 queue_delayed_work(system_freezable_power_efficient_wq,
1671 &ev->dwork, intv);
1672
1673 spin_unlock_irq(&ev->lock);
1674
1675
1676
1677
1678
1679
1680 for (i = 0; i < ARRAY_SIZE(disk_uevents); i++)
1681 if (events & disk->events & (1 << i))
1682 envp[nr_events++] = disk_uevents[i];
1683
1684 if (nr_events)
1685 kobject_uevent_env(&disk_to_dev(disk)->kobj, KOBJ_CHANGE, envp);
1686}
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696static ssize_t __disk_events_show(unsigned int events, char *buf)
1697{
1698 const char *delim = "";
1699 ssize_t pos = 0;
1700 int i;
1701
1702 for (i = 0; i < ARRAY_SIZE(disk_events_strs); i++)
1703 if (events & (1 << i)) {
1704 pos += sprintf(buf + pos, "%s%s",
1705 delim, disk_events_strs[i]);
1706 delim = " ";
1707 }
1708 if (pos)
1709 pos += sprintf(buf + pos, "\n");
1710 return pos;
1711}
1712
1713static ssize_t disk_events_show(struct device *dev,
1714 struct device_attribute *attr, char *buf)
1715{
1716 struct gendisk *disk = dev_to_disk(dev);
1717
1718 return __disk_events_show(disk->events, buf);
1719}
1720
1721static ssize_t disk_events_async_show(struct device *dev,
1722 struct device_attribute *attr, char *buf)
1723{
1724 struct gendisk *disk = dev_to_disk(dev);
1725
1726 return __disk_events_show(disk->async_events, buf);
1727}
1728
1729static ssize_t disk_events_poll_msecs_show(struct device *dev,
1730 struct device_attribute *attr,
1731 char *buf)
1732{
1733 struct gendisk *disk = dev_to_disk(dev);
1734
1735 return sprintf(buf, "%ld\n", disk->ev->poll_msecs);
1736}
1737
1738static ssize_t disk_events_poll_msecs_store(struct device *dev,
1739 struct device_attribute *attr,
1740 const char *buf, size_t count)
1741{
1742 struct gendisk *disk = dev_to_disk(dev);
1743 long intv;
1744
1745 if (!count || !sscanf(buf, "%ld", &intv))
1746 return -EINVAL;
1747
1748 if (intv < 0 && intv != -1)
1749 return -EINVAL;
1750
1751 disk_block_events(disk);
1752 disk->ev->poll_msecs = intv;
1753 __disk_unblock_events(disk, true);
1754
1755 return count;
1756}
1757
1758static const DEVICE_ATTR(events, S_IRUGO, disk_events_show, NULL);
1759static const DEVICE_ATTR(events_async, S_IRUGO, disk_events_async_show, NULL);
1760static const DEVICE_ATTR(events_poll_msecs, S_IRUGO|S_IWUSR,
1761 disk_events_poll_msecs_show,
1762 disk_events_poll_msecs_store);
1763
1764static const struct attribute *disk_events_attrs[] = {
1765 &dev_attr_events.attr,
1766 &dev_attr_events_async.attr,
1767 &dev_attr_events_poll_msecs.attr,
1768 NULL,
1769};
1770
1771
1772
1773
1774
1775
1776
1777static int disk_events_set_dfl_poll_msecs(const char *val,
1778 const struct kernel_param *kp)
1779{
1780 struct disk_events *ev;
1781 int ret;
1782
1783 ret = param_set_ulong(val, kp);
1784 if (ret < 0)
1785 return ret;
1786
1787 mutex_lock(&disk_events_mutex);
1788
1789 list_for_each_entry(ev, &disk_events, node)
1790 disk_flush_events(ev->disk, 0);
1791
1792 mutex_unlock(&disk_events_mutex);
1793
1794 return 0;
1795}
1796
1797static const struct kernel_param_ops disk_events_dfl_poll_msecs_param_ops = {
1798 .set = disk_events_set_dfl_poll_msecs,
1799 .get = param_get_ulong,
1800};
1801
1802#undef MODULE_PARAM_PREFIX
1803#define MODULE_PARAM_PREFIX "block."
1804
1805module_param_cb(events_dfl_poll_msecs, &disk_events_dfl_poll_msecs_param_ops,
1806 &disk_events_dfl_poll_msecs, 0644);
1807
1808
1809
1810
1811static void disk_alloc_events(struct gendisk *disk)
1812{
1813 struct disk_events *ev;
1814
1815 if (!disk->fops->check_events)
1816 return;
1817
1818 ev = kzalloc(sizeof(*ev), GFP_KERNEL);
1819 if (!ev) {
1820 pr_warn("%s: failed to initialize events\n", disk->disk_name);
1821 return;
1822 }
1823
1824 INIT_LIST_HEAD(&ev->node);
1825 ev->disk = disk;
1826 spin_lock_init(&ev->lock);
1827 mutex_init(&ev->block_mutex);
1828 ev->block = 1;
1829 ev->poll_msecs = -1;
1830 INIT_DELAYED_WORK(&ev->dwork, disk_events_workfn);
1831
1832 disk->ev = ev;
1833}
1834
1835static void disk_add_events(struct gendisk *disk)
1836{
1837 if (!disk->ev)
1838 return;
1839
1840
1841 if (sysfs_create_files(&disk_to_dev(disk)->kobj, disk_events_attrs) < 0)
1842 pr_warn("%s: failed to create sysfs files for events\n",
1843 disk->disk_name);
1844
1845 mutex_lock(&disk_events_mutex);
1846 list_add_tail(&disk->ev->node, &disk_events);
1847 mutex_unlock(&disk_events_mutex);
1848
1849
1850
1851
1852
1853 __disk_unblock_events(disk, true);
1854}
1855
1856static void disk_del_events(struct gendisk *disk)
1857{
1858 if (!disk->ev)
1859 return;
1860
1861 disk_block_events(disk);
1862
1863 mutex_lock(&disk_events_mutex);
1864 list_del_init(&disk->ev->node);
1865 mutex_unlock(&disk_events_mutex);
1866
1867 sysfs_remove_files(&disk_to_dev(disk)->kobj, disk_events_attrs);
1868}
1869
1870static void disk_release_events(struct gendisk *disk)
1871{
1872
1873 WARN_ON_ONCE(disk->ev && disk->ev->block != 1);
1874 kfree(disk->ev);
1875}
1876