5 #include <linux/module.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/init.h>
12 #include <linux/spinlock.h>
13 #include <linux/proc_fs.h>
14 #include <linux/seq_file.h>
15 #include <linux/slab.h>
16 #include <linux/kmod.h>
17 #include <linux/kobj_map.h>
18 #include <linux/mutex.h>
19 #include <linux/idr.h>
20 #include <linux/log2.h>
21 #include <linux/pm_runtime.h>
25 static DEFINE_MUTEX(block_class_lock);
26 struct kobject *block_depr;
28 /* for extended dynamic devt allocation, currently only one major is used */
29 #define NR_EXT_DEVT (1 << MINORBITS)
31 /* For extended devt allocation. ext_devt_mutex prevents look up
32 * results from going away underneath its user.
34 static DEFINE_MUTEX(ext_devt_mutex);
35 static DEFINE_IDR(ext_devt_idr);
37 static struct device_type disk_type;
39 static void disk_check_events(struct disk_events *ev,
40 unsigned int *clearing_ptr);
41 static void disk_alloc_events(struct gendisk *disk);
42 static void disk_add_events(struct gendisk *disk);
43 static void disk_del_events(struct gendisk *disk);
44 static void disk_release_events(struct gendisk *disk);
47 * disk_get_part - get partition
48 * @disk: disk to look partition from
49 * @partno: partition number
51 * Look for partition @partno from @disk. If found, increment
52 * reference count and return it.
58 * Pointer to the found partition on success, NULL if not found.
60 struct hd_struct *disk_get_part(struct gendisk *disk, int partno)
62 struct hd_struct *part = NULL;
63 struct disk_part_tbl *ptbl;
65 if (unlikely(partno < 0))
70 ptbl = rcu_dereference(disk->part_tbl);
71 if (likely(partno < ptbl->len)) {
72 part = rcu_dereference(ptbl->part[partno]);
74 get_device(part_to_dev(part));
81 EXPORT_SYMBOL_GPL(disk_get_part);
84 * disk_part_iter_init - initialize partition iterator
85 * @piter: iterator to initialize
86 * @disk: disk to iterate over
87 * @flags: DISK_PITER_* flags
89 * Initialize @piter so that it iterates over partitions of @disk.
94 void disk_part_iter_init(struct disk_part_iter *piter, struct gendisk *disk,
97 struct disk_part_tbl *ptbl;
100 ptbl = rcu_dereference(disk->part_tbl);
105 if (flags & DISK_PITER_REVERSE)
106 piter->idx = ptbl->len - 1;
107 else if (flags & (DISK_PITER_INCL_PART0 | DISK_PITER_INCL_EMPTY_PART0))
112 piter->flags = flags;
116 EXPORT_SYMBOL_GPL(disk_part_iter_init);
119 * disk_part_iter_next - proceed iterator to the next partition and return it
120 * @piter: iterator of interest
122 * Proceed @piter to the next partition and return it.
127 struct hd_struct *disk_part_iter_next(struct disk_part_iter *piter)
129 struct disk_part_tbl *ptbl;
132 /* put the last partition */
133 disk_put_part(piter->part);
138 ptbl = rcu_dereference(piter->disk->part_tbl);
140 /* determine iteration parameters */
141 if (piter->flags & DISK_PITER_REVERSE) {
143 if (piter->flags & (DISK_PITER_INCL_PART0 |
144 DISK_PITER_INCL_EMPTY_PART0))
153 /* iterate to the next partition */
154 for (; piter->idx != end; piter->idx += inc) {
155 struct hd_struct *part;
157 part = rcu_dereference(ptbl->part[piter->idx]);
160 if (!part_nr_sects_read(part) &&
161 !(piter->flags & DISK_PITER_INCL_EMPTY) &&
162 !(piter->flags & DISK_PITER_INCL_EMPTY_PART0 &&
166 get_device(part_to_dev(part));
176 EXPORT_SYMBOL_GPL(disk_part_iter_next);
179 * disk_part_iter_exit - finish up partition iteration
180 * @piter: iter of interest
182 * Called when iteration is over. Cleans up @piter.
187 void disk_part_iter_exit(struct disk_part_iter *piter)
189 disk_put_part(piter->part);
192 EXPORT_SYMBOL_GPL(disk_part_iter_exit);
194 static inline int sector_in_part(struct hd_struct *part, sector_t sector)
196 return part->start_sect <= sector &&
197 sector < part->start_sect + part_nr_sects_read(part);
201 * disk_map_sector_rcu - map sector to partition
202 * @disk: gendisk of interest
203 * @sector: sector to map
205 * Find out which partition @sector maps to on @disk. This is
206 * primarily used for stats accounting.
209 * RCU read locked. The returned partition pointer is valid only
210 * while preemption is disabled.
213 * Found partition on success, part0 is returned if no partition matches
215 struct hd_struct *disk_map_sector_rcu(struct gendisk *disk, sector_t sector)
217 struct disk_part_tbl *ptbl;
218 struct hd_struct *part;
221 ptbl = rcu_dereference(disk->part_tbl);
223 part = rcu_dereference(ptbl->last_lookup);
224 if (part && sector_in_part(part, sector))
227 for (i = 1; i < ptbl->len; i++) {
228 part = rcu_dereference(ptbl->part[i]);
230 if (part && sector_in_part(part, sector)) {
231 rcu_assign_pointer(ptbl->last_lookup, part);
237 EXPORT_SYMBOL_GPL(disk_map_sector_rcu);
240 * Can be deleted altogether. Later.
243 static struct blk_major_name {
244 struct blk_major_name *next;
247 } *major_names[BLKDEV_MAJOR_HASH_SIZE];
249 /* index in the above - for now: assume no multimajor ranges */
250 static inline int major_to_index(unsigned major)
252 return major % BLKDEV_MAJOR_HASH_SIZE;
255 #ifdef CONFIG_PROC_FS
256 void blkdev_show(struct seq_file *seqf, off_t offset)
258 struct blk_major_name *dp;
260 if (offset < BLKDEV_MAJOR_HASH_SIZE) {
261 mutex_lock(&block_class_lock);
262 for (dp = major_names[offset]; dp; dp = dp->next)
263 seq_printf(seqf, "%3d %s\n", dp->major, dp->name);
264 mutex_unlock(&block_class_lock);
267 #endif /* CONFIG_PROC_FS */
270 * register_blkdev - register a new block device
272 * @major: the requested major device number [1..255]. If @major=0, try to
273 * allocate any unused major number.
274 * @name: the name of the new block device as a zero terminated string
276 * The @name must be unique within the system.
278 * The return value depends on the @major input parameter.
279 * - if a major device number was requested in range [1..255] then the
280 * function returns zero on success, or a negative error code
281 * - if any unused major number was requested with @major=0 parameter
282 * then the return value is the allocated major number in range
283 * [1..255] or a negative error code otherwise
285 int register_blkdev(unsigned int major, const char *name)
287 struct blk_major_name **n, *p;
290 mutex_lock(&block_class_lock);
294 for (index = ARRAY_SIZE(major_names)-1; index > 0; index--) {
295 if (major_names[index] == NULL)
300 printk("register_blkdev: failed to get major for %s\n",
309 p = kmalloc(sizeof(struct blk_major_name), GFP_KERNEL);
316 strlcpy(p->name, name, sizeof(p->name));
318 index = major_to_index(major);
320 for (n = &major_names[index]; *n; n = &(*n)->next) {
321 if ((*n)->major == major)
330 printk("register_blkdev: cannot get major %d for %s\n",
335 mutex_unlock(&block_class_lock);
339 EXPORT_SYMBOL(register_blkdev);
341 void unregister_blkdev(unsigned int major, const char *name)
343 struct blk_major_name **n;
344 struct blk_major_name *p = NULL;
345 int index = major_to_index(major);
347 mutex_lock(&block_class_lock);
348 for (n = &major_names[index]; *n; n = &(*n)->next)
349 if ((*n)->major == major)
351 if (!*n || strcmp((*n)->name, name)) {
357 mutex_unlock(&block_class_lock);
361 EXPORT_SYMBOL(unregister_blkdev);
363 static struct kobj_map *bdev_map;
366 * blk_mangle_minor - scatter minor numbers apart
367 * @minor: minor number to mangle
369 * Scatter consecutively allocated @minor number apart if MANGLE_DEVT
370 * is enabled. Mangling twice gives the original value.
378 static int blk_mangle_minor(int minor)
380 #ifdef CONFIG_DEBUG_BLOCK_EXT_DEVT
383 for (i = 0; i < MINORBITS / 2; i++) {
384 int low = minor & (1 << i);
385 int high = minor & (1 << (MINORBITS - 1 - i));
386 int distance = MINORBITS - 1 - 2 * i;
388 minor ^= low | high; /* clear both bits */
389 low <<= distance; /* swap the positions */
391 minor |= low | high; /* and set */
398 * blk_alloc_devt - allocate a dev_t for a partition
399 * @part: partition to allocate dev_t for
400 * @devt: out parameter for resulting dev_t
402 * Allocate a dev_t for block device.
405 * 0 on success, allocated dev_t is returned in *@devt. -errno on
411 int blk_alloc_devt(struct hd_struct *part, dev_t *devt)
413 struct gendisk *disk = part_to_disk(part);
416 /* in consecutive minor range? */
417 if (part->partno < disk->minors) {
418 *devt = MKDEV(disk->major, disk->first_minor + part->partno);
422 /* allocate ext devt */
423 mutex_lock(&ext_devt_mutex);
424 idx = idr_alloc(&ext_devt_idr, part, 0, NR_EXT_DEVT, GFP_KERNEL);
425 mutex_unlock(&ext_devt_mutex);
427 return idx == -ENOSPC ? -EBUSY : idx;
429 *devt = MKDEV(BLOCK_EXT_MAJOR, blk_mangle_minor(idx));
434 * blk_free_devt - free a dev_t
435 * @devt: dev_t to free
437 * Free @devt which was allocated using blk_alloc_devt().
442 void blk_free_devt(dev_t devt)
446 if (devt == MKDEV(0, 0))
449 if (MAJOR(devt) == BLOCK_EXT_MAJOR) {
450 mutex_lock(&ext_devt_mutex);
451 idr_remove(&ext_devt_idr, blk_mangle_minor(MINOR(devt)));
452 mutex_unlock(&ext_devt_mutex);
456 static char *bdevt_str(dev_t devt, char *buf)
458 if (MAJOR(devt) <= 0xff && MINOR(devt) <= 0xff) {
459 char tbuf[BDEVT_SIZE];
460 snprintf(tbuf, BDEVT_SIZE, "%02x%02x", MAJOR(devt), MINOR(devt));
461 snprintf(buf, BDEVT_SIZE, "%-9s", tbuf);
463 snprintf(buf, BDEVT_SIZE, "%03x:%05x", MAJOR(devt), MINOR(devt));
469 * Register device numbers dev..(dev+range-1)
470 * range must be nonzero
471 * The hash chain is sorted on range, so that subranges can override.
473 void blk_register_region(dev_t devt, unsigned long range, struct module *module,
474 struct kobject *(*probe)(dev_t, int *, void *),
475 int (*lock)(dev_t, void *), void *data)
477 kobj_map(bdev_map, devt, range, module, probe, lock, data);
480 EXPORT_SYMBOL(blk_register_region);
482 void blk_unregister_region(dev_t devt, unsigned long range)
484 kobj_unmap(bdev_map, devt, range);
487 EXPORT_SYMBOL(blk_unregister_region);
489 static struct kobject *exact_match(dev_t devt, int *partno, void *data)
491 struct gendisk *p = data;
493 return &disk_to_dev(p)->kobj;
496 static int exact_lock(dev_t devt, void *data)
498 struct gendisk *p = data;
505 static void register_disk(struct gendisk *disk)
507 struct device *ddev = disk_to_dev(disk);
508 struct block_device *bdev;
509 struct disk_part_iter piter;
510 struct hd_struct *part;
513 ddev->parent = disk->driverfs_dev;
515 dev_set_name(ddev, "%s", disk->disk_name);
517 /* delay uevents, until we scanned partition table */
518 dev_set_uevent_suppress(ddev, 1);
520 if (device_add(ddev))
522 if (!sysfs_deprecated) {
523 err = sysfs_create_link(block_depr, &ddev->kobj,
524 kobject_name(&ddev->kobj));
532 * avoid probable deadlock caused by allocating memory with
533 * GFP_KERNEL in runtime_resume callback of its all ancestor
536 pm_runtime_set_memalloc_noio(ddev, true);
538 disk->part0.holder_dir = kobject_create_and_add("holders", &ddev->kobj);
539 disk->slave_dir = kobject_create_and_add("slaves", &ddev->kobj);
541 /* No minors to use for partitions */
542 if (!disk_part_scan_enabled(disk))
545 /* No such device (e.g., media were just removed) */
546 if (!get_capacity(disk))
549 bdev = bdget_disk(disk, 0);
553 bdev->bd_invalidated = 1;
554 err = blkdev_get(bdev, FMODE_READ, NULL);
557 blkdev_put(bdev, FMODE_READ);
560 /* announce disk after possible partitions are created */
561 dev_set_uevent_suppress(ddev, 0);
562 kobject_uevent(&ddev->kobj, KOBJ_ADD);
564 /* announce possible partitions */
565 disk_part_iter_init(&piter, disk, 0);
566 while ((part = disk_part_iter_next(&piter)))
567 kobject_uevent(&part_to_dev(part)->kobj, KOBJ_ADD);
568 disk_part_iter_exit(&piter);
572 * add_disk - add partitioning information to kernel list
573 * @disk: per-device partitioning information
575 * This function registers the partitioning information in @disk
578 * FIXME: error handling
580 void add_disk(struct gendisk *disk)
582 struct backing_dev_info *bdi;
586 /* minors == 0 indicates to use ext devt from part0 and should
587 * be accompanied with EXT_DEVT flag. Make sure all
588 * parameters make sense.
590 WARN_ON(disk->minors && !(disk->major || disk->first_minor));
591 WARN_ON(!disk->minors && !(disk->flags & GENHD_FL_EXT_DEVT));
593 disk->flags |= GENHD_FL_UP;
595 retval = blk_alloc_devt(&disk->part0, &devt);
600 disk_to_dev(disk)->devt = devt;
602 /* ->major and ->first_minor aren't supposed to be
603 * dereferenced from here on, but set them just in case.
605 disk->major = MAJOR(devt);
606 disk->first_minor = MINOR(devt);
608 disk_alloc_events(disk);
610 /* Register BDI before referencing it from bdev */
611 bdi = &disk->queue->backing_dev_info;
612 bdi_register_dev(bdi, disk_devt(disk));
614 blk_register_region(disk_devt(disk), disk->minors, NULL,
615 exact_match, exact_lock, disk);
617 blk_register_queue(disk);
620 * Take an extra ref on queue which will be put on disk_release()
621 * so that it sticks around as long as @disk is there.
623 WARN_ON_ONCE(!blk_get_queue(disk->queue));
625 retval = sysfs_create_link(&disk_to_dev(disk)->kobj, &bdi->dev->kobj,
629 disk_add_events(disk);
631 EXPORT_SYMBOL(add_disk);
633 void del_gendisk(struct gendisk *disk)
635 struct disk_part_iter piter;
636 struct hd_struct *part;
638 disk_del_events(disk);
640 /* invalidate stuff */
641 disk_part_iter_init(&piter, disk,
642 DISK_PITER_INCL_EMPTY | DISK_PITER_REVERSE);
643 while ((part = disk_part_iter_next(&piter))) {
644 invalidate_partition(disk, part->partno);
645 delete_partition(disk, part->partno);
647 disk_part_iter_exit(&piter);
649 invalidate_partition(disk, 0);
650 set_capacity(disk, 0);
651 disk->flags &= ~GENHD_FL_UP;
653 sysfs_remove_link(&disk_to_dev(disk)->kobj, "bdi");
654 bdi_unregister(&disk->queue->backing_dev_info);
655 blk_unregister_queue(disk);
656 blk_unregister_region(disk_devt(disk), disk->minors);
658 part_stat_set_all(&disk->part0, 0);
659 disk->part0.stamp = 0;
661 kobject_put(disk->part0.holder_dir);
662 kobject_put(disk->slave_dir);
663 disk->driverfs_dev = NULL;
664 if (!sysfs_deprecated)
665 sysfs_remove_link(block_depr, dev_name(disk_to_dev(disk)));
666 pm_runtime_set_memalloc_noio(disk_to_dev(disk), false);
667 device_del(disk_to_dev(disk));
668 blk_free_devt(disk_to_dev(disk)->devt);
670 EXPORT_SYMBOL(del_gendisk);
673 * get_gendisk - get partitioning information for a given device
674 * @devt: device to get partitioning information for
675 * @partno: returned partition index
677 * This function gets the structure containing partitioning
678 * information for the given device @devt.
680 struct gendisk *get_gendisk(dev_t devt, int *partno)
682 struct gendisk *disk = NULL;
684 if (MAJOR(devt) != BLOCK_EXT_MAJOR) {
685 struct kobject *kobj;
687 kobj = kobj_lookup(bdev_map, devt, partno);
689 disk = dev_to_disk(kobj_to_dev(kobj));
691 struct hd_struct *part;
693 mutex_lock(&ext_devt_mutex);
694 part = idr_find(&ext_devt_idr, blk_mangle_minor(MINOR(devt)));
695 if (part && get_disk(part_to_disk(part))) {
696 *partno = part->partno;
697 disk = part_to_disk(part);
699 mutex_unlock(&ext_devt_mutex);
704 EXPORT_SYMBOL(get_gendisk);
707 * bdget_disk - do bdget() by gendisk and partition number
708 * @disk: gendisk of interest
709 * @partno: partition number
711 * Find partition @partno from @disk, do bdget() on it.
717 * Resulting block_device on success, NULL on failure.
719 struct block_device *bdget_disk(struct gendisk *disk, int partno)
721 struct hd_struct *part;
722 struct block_device *bdev = NULL;
724 part = disk_get_part(disk, partno);
726 bdev = bdget(part_devt(part));
731 EXPORT_SYMBOL(bdget_disk);
734 * print a full list of all partitions - intended for places where the root
735 * filesystem can't be mounted and thus to give the victim some idea of what
738 void __init printk_all_partitions(void)
740 struct class_dev_iter iter;
743 class_dev_iter_init(&iter, &block_class, NULL, &disk_type);
744 while ((dev = class_dev_iter_next(&iter))) {
745 struct gendisk *disk = dev_to_disk(dev);
746 struct disk_part_iter piter;
747 struct hd_struct *part;
748 char name_buf[BDEVNAME_SIZE];
749 char devt_buf[BDEVT_SIZE];
752 * Don't show empty devices or things that have been
755 if (get_capacity(disk) == 0 ||
756 (disk->flags & GENHD_FL_SUPPRESS_PARTITION_INFO))
760 * Note, unlike /proc/partitions, I am showing the
761 * numbers in hex - the same format as the root=
764 disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0);
765 while ((part = disk_part_iter_next(&piter))) {
766 bool is_part0 = part == &disk->part0;
768 printk("%s%s %10llu %s %s", is_part0 ? "" : " ",
769 bdevt_str(part_devt(part), devt_buf),
770 (unsigned long long)part_nr_sects_read(part) >> 1
771 , disk_name(disk, part->partno, name_buf),
772 part->info ? part->info->uuid : "");
774 if (disk->driverfs_dev != NULL &&
775 disk->driverfs_dev->driver != NULL)
776 printk(" driver: %s\n",
777 disk->driverfs_dev->driver->name);
779 printk(" (driver?)\n");
783 disk_part_iter_exit(&piter);
785 class_dev_iter_exit(&iter);
788 #ifdef CONFIG_PROC_FS
790 static void *disk_seqf_start(struct seq_file *seqf, loff_t *pos)
793 struct class_dev_iter *iter;
796 iter = kmalloc(sizeof(*iter), GFP_KERNEL);
798 return ERR_PTR(-ENOMEM);
800 seqf->private = iter;
801 class_dev_iter_init(iter, &block_class, NULL, &disk_type);
803 dev = class_dev_iter_next(iter);
808 return dev_to_disk(dev);
811 static void *disk_seqf_next(struct seq_file *seqf, void *v, loff_t *pos)
816 dev = class_dev_iter_next(seqf->private);
818 return dev_to_disk(dev);
823 static void disk_seqf_stop(struct seq_file *seqf, void *v)
825 struct class_dev_iter *iter = seqf->private;
827 /* stop is called even after start failed :-( */
829 class_dev_iter_exit(iter);
834 static void *show_partition_start(struct seq_file *seqf, loff_t *pos)
838 p = disk_seqf_start(seqf, pos);
839 if (!IS_ERR_OR_NULL(p) && !*pos)
840 seq_puts(seqf, "major minor #blocks name\n\n");
844 static int show_partition(struct seq_file *seqf, void *v)
846 struct gendisk *sgp = v;
847 struct disk_part_iter piter;
848 struct hd_struct *part;
849 char buf[BDEVNAME_SIZE];
851 /* Don't show non-partitionable removeable devices or empty devices */
852 if (!get_capacity(sgp) || (!disk_max_parts(sgp) &&
853 (sgp->flags & GENHD_FL_REMOVABLE)))
855 if (sgp->flags & GENHD_FL_SUPPRESS_PARTITION_INFO)
858 /* show the full disk and all non-0 size partitions of it */
859 disk_part_iter_init(&piter, sgp, DISK_PITER_INCL_PART0);
860 while ((part = disk_part_iter_next(&piter)))
861 seq_printf(seqf, "%4d %7d %10llu %s\n",
862 MAJOR(part_devt(part)), MINOR(part_devt(part)),
863 (unsigned long long)part_nr_sects_read(part) >> 1,
864 disk_name(sgp, part->partno, buf));
865 disk_part_iter_exit(&piter);
870 static const struct seq_operations partitions_op = {
871 .start = show_partition_start,
872 .next = disk_seqf_next,
873 .stop = disk_seqf_stop,
874 .show = show_partition
877 static int partitions_open(struct inode *inode, struct file *file)
879 return seq_open(file, &partitions_op);
882 static const struct file_operations proc_partitions_operations = {
883 .open = partitions_open,
886 .release = seq_release,
891 static struct kobject *base_probe(dev_t devt, int *partno, void *data)
893 if (request_module("block-major-%d-%d", MAJOR(devt), MINOR(devt)) > 0)
894 /* Make old-style 2.4 aliases work */
895 request_module("block-major-%d", MAJOR(devt));
899 static int __init genhd_device_init(void)
903 block_class.dev_kobj = sysfs_dev_block_kobj;
904 error = class_register(&block_class);
907 bdev_map = kobj_map_init(base_probe, &block_class_lock);
910 register_blkdev(BLOCK_EXT_MAJOR, "blkext");
912 /* create top-level block dir */
913 if (!sysfs_deprecated)
914 block_depr = kobject_create_and_add("block", NULL);
918 subsys_initcall(genhd_device_init);
920 static ssize_t disk_range_show(struct device *dev,
921 struct device_attribute *attr, char *buf)
923 struct gendisk *disk = dev_to_disk(dev);
925 return sprintf(buf, "%d\n", disk->minors);
928 static ssize_t disk_ext_range_show(struct device *dev,
929 struct device_attribute *attr, char *buf)
931 struct gendisk *disk = dev_to_disk(dev);
933 return sprintf(buf, "%d\n", disk_max_parts(disk));
936 static ssize_t disk_removable_show(struct device *dev,
937 struct device_attribute *attr, char *buf)
939 struct gendisk *disk = dev_to_disk(dev);
941 return sprintf(buf, "%d\n",
942 (disk->flags & GENHD_FL_REMOVABLE ? 1 : 0));
945 static ssize_t disk_ro_show(struct device *dev,
946 struct device_attribute *attr, char *buf)
948 struct gendisk *disk = dev_to_disk(dev);
950 return sprintf(buf, "%d\n", get_disk_ro(disk) ? 1 : 0);
953 static ssize_t disk_capability_show(struct device *dev,
954 struct device_attribute *attr, char *buf)
956 struct gendisk *disk = dev_to_disk(dev);
958 return sprintf(buf, "%x\n", disk->flags);
961 static ssize_t disk_alignment_offset_show(struct device *dev,
962 struct device_attribute *attr,
965 struct gendisk *disk = dev_to_disk(dev);
967 return sprintf(buf, "%d\n", queue_alignment_offset(disk->queue));
970 static ssize_t disk_discard_alignment_show(struct device *dev,
971 struct device_attribute *attr,
974 struct gendisk *disk = dev_to_disk(dev);
976 return sprintf(buf, "%d\n", queue_discard_alignment(disk->queue));
979 static DEVICE_ATTR(range, S_IRUGO, disk_range_show, NULL);
980 static DEVICE_ATTR(ext_range, S_IRUGO, disk_ext_range_show, NULL);
981 static DEVICE_ATTR(removable, S_IRUGO, disk_removable_show, NULL);
982 static DEVICE_ATTR(ro, S_IRUGO, disk_ro_show, NULL);
983 static DEVICE_ATTR(size, S_IRUGO, part_size_show, NULL);
984 static DEVICE_ATTR(alignment_offset, S_IRUGO, disk_alignment_offset_show, NULL);
985 static DEVICE_ATTR(discard_alignment, S_IRUGO, disk_discard_alignment_show,
987 static DEVICE_ATTR(capability, S_IRUGO, disk_capability_show, NULL);
988 static DEVICE_ATTR(stat, S_IRUGO, part_stat_show, NULL);
989 static DEVICE_ATTR(inflight, S_IRUGO, part_inflight_show, NULL);
990 #ifdef CONFIG_FAIL_MAKE_REQUEST
991 static struct device_attribute dev_attr_fail =
992 __ATTR(make-it-fail, S_IRUGO|S_IWUSR, part_fail_show, part_fail_store);
994 #ifdef CONFIG_FAIL_IO_TIMEOUT
995 static struct device_attribute dev_attr_fail_timeout =
996 __ATTR(io-timeout-fail, S_IRUGO|S_IWUSR, part_timeout_show,
1000 static struct attribute *disk_attrs[] = {
1001 &dev_attr_range.attr,
1002 &dev_attr_ext_range.attr,
1003 &dev_attr_removable.attr,
1005 &dev_attr_size.attr,
1006 &dev_attr_alignment_offset.attr,
1007 &dev_attr_discard_alignment.attr,
1008 &dev_attr_capability.attr,
1009 &dev_attr_stat.attr,
1010 &dev_attr_inflight.attr,
1011 #ifdef CONFIG_FAIL_MAKE_REQUEST
1012 &dev_attr_fail.attr,
1014 #ifdef CONFIG_FAIL_IO_TIMEOUT
1015 &dev_attr_fail_timeout.attr,
1020 static struct attribute_group disk_attr_group = {
1021 .attrs = disk_attrs,
1024 static const struct attribute_group *disk_attr_groups[] = {
1030 * disk_replace_part_tbl - replace disk->part_tbl in RCU-safe way
1031 * @disk: disk to replace part_tbl for
1032 * @new_ptbl: new part_tbl to install
1034 * Replace disk->part_tbl with @new_ptbl in RCU-safe way. The
1035 * original ptbl is freed using RCU callback.
1038 * Matching bd_mutx locked.
1040 static void disk_replace_part_tbl(struct gendisk *disk,
1041 struct disk_part_tbl *new_ptbl)
1043 struct disk_part_tbl *old_ptbl = disk->part_tbl;
1045 rcu_assign_pointer(disk->part_tbl, new_ptbl);
1048 rcu_assign_pointer(old_ptbl->last_lookup, NULL);
1049 kfree_rcu(old_ptbl, rcu_head);
1054 * disk_expand_part_tbl - expand disk->part_tbl
1055 * @disk: disk to expand part_tbl for
1056 * @partno: expand such that this partno can fit in
1058 * Expand disk->part_tbl such that @partno can fit in. disk->part_tbl
1059 * uses RCU to allow unlocked dereferencing for stats and other stuff.
1062 * Matching bd_mutex locked, might sleep.
1065 * 0 on success, -errno on failure.
1067 int disk_expand_part_tbl(struct gendisk *disk, int partno)
1069 struct disk_part_tbl *old_ptbl = disk->part_tbl;
1070 struct disk_part_tbl *new_ptbl;
1071 int len = old_ptbl ? old_ptbl->len : 0;
1072 int target = partno + 1;
1076 /* disk_max_parts() is zero during initialization, ignore if so */
1077 if (disk_max_parts(disk) && target > disk_max_parts(disk))
1083 size = sizeof(*new_ptbl) + target * sizeof(new_ptbl->part[0]);
1084 new_ptbl = kzalloc_node(size, GFP_KERNEL, disk->node_id);
1088 new_ptbl->len = target;
1090 for (i = 0; i < len; i++)
1091 rcu_assign_pointer(new_ptbl->part[i], old_ptbl->part[i]);
1093 disk_replace_part_tbl(disk, new_ptbl);
1097 static void disk_release(struct device *dev)
1099 struct gendisk *disk = dev_to_disk(dev);
1101 disk_release_events(disk);
1102 kfree(disk->random);
1103 disk_replace_part_tbl(disk, NULL);
1104 free_part_stats(&disk->part0);
1105 free_part_info(&disk->part0);
1107 blk_put_queue(disk->queue);
1111 static int disk_uevent(struct device *dev, struct kobj_uevent_env *env)
1113 struct gendisk *disk = dev_to_disk(dev);
1114 struct disk_part_iter piter;
1115 struct hd_struct *part;
1118 disk_part_iter_init(&piter, disk, 0);
1119 while((part = disk_part_iter_next(&piter)))
1121 disk_part_iter_exit(&piter);
1122 add_uevent_var(env, "NPARTS=%u", cnt);
1126 struct class block_class = {
1130 static char *block_devnode(struct device *dev, umode_t *mode,
1131 kuid_t *uid, kgid_t *gid)
1133 struct gendisk *disk = dev_to_disk(dev);
1136 return disk->devnode(disk, mode);
1140 static struct device_type disk_type = {
1142 .groups = disk_attr_groups,
1143 .release = disk_release,
1144 .devnode = block_devnode,
1145 .uevent = disk_uevent,
1148 #ifdef CONFIG_PROC_FS
1150 * aggregate disk stat collector. Uses the same stats that the sysfs
1151 * entries do, above, but makes them available through one seq_file.
1153 * The output looks suspiciously like /proc/partitions with a bunch of
1156 static int diskstats_show(struct seq_file *seqf, void *v)
1158 struct gendisk *gp = v;
1159 struct disk_part_iter piter;
1160 struct hd_struct *hd;
1161 char buf[BDEVNAME_SIZE];
1165 if (&disk_to_dev(gp)->kobj.entry == block_class.devices.next)
1166 seq_puts(seqf, "major minor name"
1167 " rio rmerge rsect ruse wio wmerge "
1168 "wsect wuse running use aveq"
1172 disk_part_iter_init(&piter, gp, DISK_PITER_INCL_EMPTY_PART0);
1173 while ((hd = disk_part_iter_next(&piter))) {
1174 cpu = part_stat_lock();
1175 part_round_stats(cpu, hd);
1177 seq_printf(seqf, "%4d %7d %s %lu %lu %lu "
1178 "%u %lu %lu %lu %u %u %u %u\n",
1179 MAJOR(part_devt(hd)), MINOR(part_devt(hd)),
1180 disk_name(gp, hd->partno, buf),
1181 part_stat_read(hd, ios[READ]),
1182 part_stat_read(hd, merges[READ]),
1183 part_stat_read(hd, sectors[READ]),
1184 jiffies_to_msecs(part_stat_read(hd, ticks[READ])),
1185 part_stat_read(hd, ios[WRITE]),
1186 part_stat_read(hd, merges[WRITE]),
1187 part_stat_read(hd, sectors[WRITE]),
1188 jiffies_to_msecs(part_stat_read(hd, ticks[WRITE])),
1190 jiffies_to_msecs(part_stat_read(hd, io_ticks)),
1191 jiffies_to_msecs(part_stat_read(hd, time_in_queue))
1194 disk_part_iter_exit(&piter);
1199 static const struct seq_operations diskstats_op = {
1200 .start = disk_seqf_start,
1201 .next = disk_seqf_next,
1202 .stop = disk_seqf_stop,
1203 .show = diskstats_show
1206 static int diskstats_open(struct inode *inode, struct file *file)
1208 return seq_open(file, &diskstats_op);
1211 static const struct file_operations proc_diskstats_operations = {
1212 .open = diskstats_open,
1214 .llseek = seq_lseek,
1215 .release = seq_release,
1218 static int __init proc_genhd_init(void)
1220 proc_create("diskstats", 0, NULL, &proc_diskstats_operations);
1221 proc_create("partitions", 0, NULL, &proc_partitions_operations);
1224 module_init(proc_genhd_init);
1225 #endif /* CONFIG_PROC_FS */
1227 dev_t blk_lookup_devt(const char *name, int partno)
1229 dev_t devt = MKDEV(0, 0);
1230 struct class_dev_iter iter;
1233 class_dev_iter_init(&iter, &block_class, NULL, &disk_type);
1234 while ((dev = class_dev_iter_next(&iter))) {
1235 struct gendisk *disk = dev_to_disk(dev);
1236 struct hd_struct *part;
1238 if (strcmp(dev_name(dev), name))
1241 if (partno < disk->minors) {
1242 /* We need to return the right devno, even
1243 * if the partition doesn't exist yet.
1245 devt = MKDEV(MAJOR(dev->devt),
1246 MINOR(dev->devt) + partno);
1249 part = disk_get_part(disk, partno);
1251 devt = part_devt(part);
1252 disk_put_part(part);
1255 disk_put_part(part);
1257 class_dev_iter_exit(&iter);
1260 EXPORT_SYMBOL(blk_lookup_devt);
1262 struct gendisk *alloc_disk(int minors)
1264 return alloc_disk_node(minors, NUMA_NO_NODE);
1266 EXPORT_SYMBOL(alloc_disk);
1268 struct gendisk *alloc_disk_node(int minors, int node_id)
1270 struct gendisk *disk;
1272 disk = kmalloc_node(sizeof(struct gendisk),
1273 GFP_KERNEL | __GFP_ZERO, node_id);
1275 if (!init_part_stats(&disk->part0)) {
1279 disk->node_id = node_id;
1280 if (disk_expand_part_tbl(disk, 0)) {
1281 free_part_stats(&disk->part0);
1285 disk->part_tbl->part[0] = &disk->part0;
1288 * set_capacity() and get_capacity() currently don't use
1289 * seqcounter to read/update the part0->nr_sects. Still init
1290 * the counter as we can read the sectors in IO submission
1291 * patch using seqence counters.
1293 * TODO: Ideally set_capacity() and get_capacity() should be
1294 * converted to make use of bd_mutex and sequence counters.
1296 seqcount_init(&disk->part0.nr_sects_seq);
1297 hd_ref_init(&disk->part0);
1299 disk->minors = minors;
1300 rand_initialize_disk(disk);
1301 disk_to_dev(disk)->class = &block_class;
1302 disk_to_dev(disk)->type = &disk_type;
1303 device_initialize(disk_to_dev(disk));
1307 EXPORT_SYMBOL(alloc_disk_node);
1309 struct kobject *get_disk(struct gendisk *disk)
1311 struct module *owner;
1312 struct kobject *kobj;
1316 owner = disk->fops->owner;
1317 if (owner && !try_module_get(owner))
1319 kobj = kobject_get(&disk_to_dev(disk)->kobj);
1328 EXPORT_SYMBOL(get_disk);
1330 void put_disk(struct gendisk *disk)
1333 kobject_put(&disk_to_dev(disk)->kobj);
1336 EXPORT_SYMBOL(put_disk);
1338 static void set_disk_ro_uevent(struct gendisk *gd, int ro)
1340 char event[] = "DISK_RO=1";
1341 char *envp[] = { event, NULL };
1345 kobject_uevent_env(&disk_to_dev(gd)->kobj, KOBJ_CHANGE, envp);
1348 void set_device_ro(struct block_device *bdev, int flag)
1350 bdev->bd_part->policy = flag;
1353 EXPORT_SYMBOL(set_device_ro);
1355 void set_disk_ro(struct gendisk *disk, int flag)
1357 struct disk_part_iter piter;
1358 struct hd_struct *part;
1360 if (disk->part0.policy != flag) {
1361 set_disk_ro_uevent(disk, flag);
1362 disk->part0.policy = flag;
1365 disk_part_iter_init(&piter, disk, DISK_PITER_INCL_EMPTY);
1366 while ((part = disk_part_iter_next(&piter)))
1367 part->policy = flag;
1368 disk_part_iter_exit(&piter);
1371 EXPORT_SYMBOL(set_disk_ro);
1373 int bdev_read_only(struct block_device *bdev)
1377 return bdev->bd_part->policy;
1380 EXPORT_SYMBOL(bdev_read_only);
1382 int invalidate_partition(struct gendisk *disk, int partno)
1385 struct block_device *bdev = bdget_disk(disk, partno);
1388 res = __invalidate_device(bdev, true);
1394 EXPORT_SYMBOL(invalidate_partition);
1397 * Disk events - monitor disk events like media change and eject request.
1399 struct disk_events {
1400 struct list_head node; /* all disk_event's */
1401 struct gendisk *disk; /* the associated disk */
1404 struct mutex block_mutex; /* protects blocking */
1405 int block; /* event blocking depth */
1406 unsigned int pending; /* events already sent out */
1407 unsigned int clearing; /* events being cleared */
1409 long poll_msecs; /* interval, -1 for default */
1410 struct delayed_work dwork;
1413 static const char *disk_events_strs[] = {
1414 [ilog2(DISK_EVENT_MEDIA_CHANGE)] = "media_change",
1415 [ilog2(DISK_EVENT_EJECT_REQUEST)] = "eject_request",
1418 static char *disk_uevents[] = {
1419 [ilog2(DISK_EVENT_MEDIA_CHANGE)] = "DISK_MEDIA_CHANGE=1",
1420 [ilog2(DISK_EVENT_EJECT_REQUEST)] = "DISK_EJECT_REQUEST=1",
1423 /* list of all disk_events */
1424 static DEFINE_MUTEX(disk_events_mutex);
1425 static LIST_HEAD(disk_events);
1427 /* disable in-kernel polling by default */
1428 static unsigned long disk_events_dfl_poll_msecs = 0;
1430 static unsigned long disk_events_poll_jiffies(struct gendisk *disk)
1432 struct disk_events *ev = disk->ev;
1433 long intv_msecs = 0;
1436 * If device-specific poll interval is set, always use it. If
1437 * the default is being used, poll iff there are events which
1438 * can't be monitored asynchronously.
1440 if (ev->poll_msecs >= 0)
1441 intv_msecs = ev->poll_msecs;
1442 else if (disk->events & ~disk->async_events)
1443 intv_msecs = disk_events_dfl_poll_msecs;
1445 return msecs_to_jiffies(intv_msecs);
1449 * disk_block_events - block and flush disk event checking
1450 * @disk: disk to block events for
1452 * On return from this function, it is guaranteed that event checking
1453 * isn't in progress and won't happen until unblocked by
1454 * disk_unblock_events(). Events blocking is counted and the actual
1455 * unblocking happens after the matching number of unblocks are done.
1457 * Note that this intentionally does not block event checking from
1458 * disk_clear_events().
1463 void disk_block_events(struct gendisk *disk)
1465 struct disk_events *ev = disk->ev;
1466 unsigned long flags;
1473 * Outer mutex ensures that the first blocker completes canceling
1474 * the event work before further blockers are allowed to finish.
1476 mutex_lock(&ev->block_mutex);
1478 spin_lock_irqsave(&ev->lock, flags);
1479 cancel = !ev->block++;
1480 spin_unlock_irqrestore(&ev->lock, flags);
1483 cancel_delayed_work_sync(&disk->ev->dwork);
1485 mutex_unlock(&ev->block_mutex);
1488 static void __disk_unblock_events(struct gendisk *disk, bool check_now)
1490 struct disk_events *ev = disk->ev;
1492 unsigned long flags;
1494 spin_lock_irqsave(&ev->lock, flags);
1496 if (WARN_ON_ONCE(ev->block <= 0))
1503 * Not exactly a latency critical operation, set poll timer
1504 * slack to 25% and kick event check.
1506 intv = disk_events_poll_jiffies(disk);
1507 set_timer_slack(&ev->dwork.timer, intv / 4);
1509 queue_delayed_work(system_freezable_power_efficient_wq,
1512 queue_delayed_work(system_freezable_power_efficient_wq,
1515 spin_unlock_irqrestore(&ev->lock, flags);
1519 * disk_unblock_events - unblock disk event checking
1520 * @disk: disk to unblock events for
1522 * Undo disk_block_events(). When the block count reaches zero, it
1523 * starts events polling if configured.
1526 * Don't care. Safe to call from irq context.
1528 void disk_unblock_events(struct gendisk *disk)
1531 __disk_unblock_events(disk, false);
1535 * disk_flush_events - schedule immediate event checking and flushing
1536 * @disk: disk to check and flush events for
1537 * @mask: events to flush
1539 * Schedule immediate event checking on @disk if not blocked. Events in
1540 * @mask are scheduled to be cleared from the driver. Note that this
1541 * doesn't clear the events from @disk->ev.
1544 * If @mask is non-zero must be called with bdev->bd_mutex held.
1546 void disk_flush_events(struct gendisk *disk, unsigned int mask)
1548 struct disk_events *ev = disk->ev;
1553 spin_lock_irq(&ev->lock);
1554 ev->clearing |= mask;
1556 mod_delayed_work(system_freezable_power_efficient_wq,
1558 spin_unlock_irq(&ev->lock);
1562 * disk_clear_events - synchronously check, clear and return pending events
1563 * @disk: disk to fetch and clear events from
1564 * @mask: mask of events to be fetched and clearted
1566 * Disk events are synchronously checked and pending events in @mask
1567 * are cleared and returned. This ignores the block count.
1572 unsigned int disk_clear_events(struct gendisk *disk, unsigned int mask)
1574 const struct block_device_operations *bdops = disk->fops;
1575 struct disk_events *ev = disk->ev;
1576 unsigned int pending;
1577 unsigned int clearing = mask;
1580 /* for drivers still using the old ->media_changed method */
1581 if ((mask & DISK_EVENT_MEDIA_CHANGE) &&
1582 bdops->media_changed && bdops->media_changed(disk))
1583 return DISK_EVENT_MEDIA_CHANGE;
1587 disk_block_events(disk);
1590 * store the union of mask and ev->clearing on the stack so that the
1591 * race with disk_flush_events does not cause ambiguity (ev->clearing
1592 * can still be modified even if events are blocked).
1594 spin_lock_irq(&ev->lock);
1595 clearing |= ev->clearing;
1597 spin_unlock_irq(&ev->lock);
1599 disk_check_events(ev, &clearing);
1601 * if ev->clearing is not 0, the disk_flush_events got called in the
1602 * middle of this function, so we want to run the workfn without delay.
1604 __disk_unblock_events(disk, ev->clearing ? true : false);
1606 /* then, fetch and clear pending events */
1607 spin_lock_irq(&ev->lock);
1608 pending = ev->pending & mask;
1609 ev->pending &= ~mask;
1610 spin_unlock_irq(&ev->lock);
1611 WARN_ON_ONCE(clearing & mask);
1617 * Separate this part out so that a different pointer for clearing_ptr can be
1618 * passed in for disk_clear_events.
1620 static void disk_events_workfn(struct work_struct *work)
1622 struct delayed_work *dwork = to_delayed_work(work);
1623 struct disk_events *ev = container_of(dwork, struct disk_events, dwork);
1625 disk_check_events(ev, &ev->clearing);
1628 static void disk_check_events(struct disk_events *ev,
1629 unsigned int *clearing_ptr)
1631 struct gendisk *disk = ev->disk;
1632 char *envp[ARRAY_SIZE(disk_uevents) + 1] = { };
1633 unsigned int clearing = *clearing_ptr;
1634 unsigned int events;
1636 int nr_events = 0, i;
1639 events = disk->fops->check_events(disk, clearing);
1641 /* accumulate pending events and schedule next poll if necessary */
1642 spin_lock_irq(&ev->lock);
1644 events &= ~ev->pending;
1645 ev->pending |= events;
1646 *clearing_ptr &= ~clearing;
1648 intv = disk_events_poll_jiffies(disk);
1649 if (!ev->block && intv)
1650 queue_delayed_work(system_freezable_power_efficient_wq,
1653 spin_unlock_irq(&ev->lock);
1656 * Tell userland about new events. Only the events listed in
1657 * @disk->events are reported. Unlisted events are processed the
1658 * same internally but never get reported to userland.
1660 for (i = 0; i < ARRAY_SIZE(disk_uevents); i++)
1661 if (events & disk->events & (1 << i))
1662 envp[nr_events++] = disk_uevents[i];
1665 kobject_uevent_env(&disk_to_dev(disk)->kobj, KOBJ_CHANGE, envp);
1669 * A disk events enabled device has the following sysfs nodes under
1670 * its /sys/block/X/ directory.
1672 * events : list of all supported events
1673 * events_async : list of events which can be detected w/o polling
1674 * events_poll_msecs : polling interval, 0: disable, -1: system default
1676 static ssize_t __disk_events_show(unsigned int events, char *buf)
1678 const char *delim = "";
1682 for (i = 0; i < ARRAY_SIZE(disk_events_strs); i++)
1683 if (events & (1 << i)) {
1684 pos += sprintf(buf + pos, "%s%s",
1685 delim, disk_events_strs[i]);
1689 pos += sprintf(buf + pos, "\n");
1693 static ssize_t disk_events_show(struct device *dev,
1694 struct device_attribute *attr, char *buf)
1696 struct gendisk *disk = dev_to_disk(dev);
1698 return __disk_events_show(disk->events, buf);
1701 static ssize_t disk_events_async_show(struct device *dev,
1702 struct device_attribute *attr, char *buf)
1704 struct gendisk *disk = dev_to_disk(dev);
1706 return __disk_events_show(disk->async_events, buf);
1709 static ssize_t disk_events_poll_msecs_show(struct device *dev,
1710 struct device_attribute *attr,
1713 struct gendisk *disk = dev_to_disk(dev);
1715 return sprintf(buf, "%ld\n", disk->ev->poll_msecs);
1718 static ssize_t disk_events_poll_msecs_store(struct device *dev,
1719 struct device_attribute *attr,
1720 const char *buf, size_t count)
1722 struct gendisk *disk = dev_to_disk(dev);
1725 if (!count || !sscanf(buf, "%ld", &intv))
1728 if (intv < 0 && intv != -1)
1731 disk_block_events(disk);
1732 disk->ev->poll_msecs = intv;
1733 __disk_unblock_events(disk, true);
1738 static const DEVICE_ATTR(events, S_IRUGO, disk_events_show, NULL);
1739 static const DEVICE_ATTR(events_async, S_IRUGO, disk_events_async_show, NULL);
1740 static const DEVICE_ATTR(events_poll_msecs, S_IRUGO|S_IWUSR,
1741 disk_events_poll_msecs_show,
1742 disk_events_poll_msecs_store);
1744 static const struct attribute *disk_events_attrs[] = {
1745 &dev_attr_events.attr,
1746 &dev_attr_events_async.attr,
1747 &dev_attr_events_poll_msecs.attr,
1752 * The default polling interval can be specified by the kernel
1753 * parameter block.events_dfl_poll_msecs which defaults to 0
1754 * (disable). This can also be modified runtime by writing to
1755 * /sys/module/block/events_dfl_poll_msecs.
1757 static int disk_events_set_dfl_poll_msecs(const char *val,
1758 const struct kernel_param *kp)
1760 struct disk_events *ev;
1763 ret = param_set_ulong(val, kp);
1767 mutex_lock(&disk_events_mutex);
1769 list_for_each_entry(ev, &disk_events, node)
1770 disk_flush_events(ev->disk, 0);
1772 mutex_unlock(&disk_events_mutex);
1777 static const struct kernel_param_ops disk_events_dfl_poll_msecs_param_ops = {
1778 .set = disk_events_set_dfl_poll_msecs,
1779 .get = param_get_ulong,
1782 #undef MODULE_PARAM_PREFIX
1783 #define MODULE_PARAM_PREFIX "block."
1785 module_param_cb(events_dfl_poll_msecs, &disk_events_dfl_poll_msecs_param_ops,
1786 &disk_events_dfl_poll_msecs, 0644);
1789 * disk_{alloc|add|del|release}_events - initialize and destroy disk_events.
1791 static void disk_alloc_events(struct gendisk *disk)
1793 struct disk_events *ev;
1795 if (!disk->fops->check_events)
1798 ev = kzalloc(sizeof(*ev), GFP_KERNEL);
1800 pr_warn("%s: failed to initialize events\n", disk->disk_name);
1804 INIT_LIST_HEAD(&ev->node);
1806 spin_lock_init(&ev->lock);
1807 mutex_init(&ev->block_mutex);
1809 ev->poll_msecs = -1;
1810 INIT_DELAYED_WORK(&ev->dwork, disk_events_workfn);
1815 static void disk_add_events(struct gendisk *disk)
1820 /* FIXME: error handling */
1821 if (sysfs_create_files(&disk_to_dev(disk)->kobj, disk_events_attrs) < 0)
1822 pr_warn("%s: failed to create sysfs files for events\n",
1825 mutex_lock(&disk_events_mutex);
1826 list_add_tail(&disk->ev->node, &disk_events);
1827 mutex_unlock(&disk_events_mutex);
1830 * Block count is initialized to 1 and the following initial
1831 * unblock kicks it into action.
1833 __disk_unblock_events(disk, true);
1836 static void disk_del_events(struct gendisk *disk)
1841 disk_block_events(disk);
1843 mutex_lock(&disk_events_mutex);
1844 list_del_init(&disk->ev->node);
1845 mutex_unlock(&disk_events_mutex);
1847 sysfs_remove_files(&disk_to_dev(disk)->kobj, disk_events_attrs);
1850 static void disk_release_events(struct gendisk *disk)
1852 /* the block count should be 1 from disk_del_events() */
1853 WARN_ON_ONCE(disk->ev && disk->ev->block != 1);