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 */
424 if (!idr_pre_get(&ext_devt_idr, GFP_KERNEL))
426 mutex_lock(&ext_devt_mutex);
427 rc = idr_get_new(&ext_devt_idr, part, &idx);
428 if (!rc && idx >= NR_EXT_DEVT) {
429 idr_remove(&ext_devt_idr, idx);
432 mutex_unlock(&ext_devt_mutex);
433 } while (rc == -EAGAIN);
438 *devt = MKDEV(BLOCK_EXT_MAJOR, blk_mangle_minor(idx));
443 * blk_free_devt - free a dev_t
444 * @devt: dev_t to free
446 * Free @devt which was allocated using blk_alloc_devt().
451 void blk_free_devt(dev_t devt)
455 if (devt == MKDEV(0, 0))
458 if (MAJOR(devt) == BLOCK_EXT_MAJOR) {
459 mutex_lock(&ext_devt_mutex);
460 idr_remove(&ext_devt_idr, blk_mangle_minor(MINOR(devt)));
461 mutex_unlock(&ext_devt_mutex);
465 static char *bdevt_str(dev_t devt, char *buf)
467 if (MAJOR(devt) <= 0xff && MINOR(devt) <= 0xff) {
468 char tbuf[BDEVT_SIZE];
469 snprintf(tbuf, BDEVT_SIZE, "%02x%02x", MAJOR(devt), MINOR(devt));
470 snprintf(buf, BDEVT_SIZE, "%-9s", tbuf);
472 snprintf(buf, BDEVT_SIZE, "%03x:%05x", MAJOR(devt), MINOR(devt));
478 * Register device numbers dev..(dev+range-1)
479 * range must be nonzero
480 * The hash chain is sorted on range, so that subranges can override.
482 void blk_register_region(dev_t devt, unsigned long range, struct module *module,
483 struct kobject *(*probe)(dev_t, int *, void *),
484 int (*lock)(dev_t, void *), void *data)
486 kobj_map(bdev_map, devt, range, module, probe, lock, data);
489 EXPORT_SYMBOL(blk_register_region);
491 void blk_unregister_region(dev_t devt, unsigned long range)
493 kobj_unmap(bdev_map, devt, range);
496 EXPORT_SYMBOL(blk_unregister_region);
498 static struct kobject *exact_match(dev_t devt, int *partno, void *data)
500 struct gendisk *p = data;
502 return &disk_to_dev(p)->kobj;
505 static int exact_lock(dev_t devt, void *data)
507 struct gendisk *p = data;
514 static void register_disk(struct gendisk *disk)
516 struct device *ddev = disk_to_dev(disk);
517 struct block_device *bdev;
518 struct disk_part_iter piter;
519 struct hd_struct *part;
522 ddev->parent = disk->driverfs_dev;
524 dev_set_name(ddev, disk->disk_name);
526 /* delay uevents, until we scanned partition table */
527 dev_set_uevent_suppress(ddev, 1);
529 if (device_add(ddev))
531 if (!sysfs_deprecated) {
532 err = sysfs_create_link(block_depr, &ddev->kobj,
533 kobject_name(&ddev->kobj));
541 * avoid probable deadlock caused by allocating memory with
542 * GFP_KERNEL in runtime_resume callback of its all ancestor
545 pm_runtime_set_memalloc_noio(ddev, true);
547 disk->part0.holder_dir = kobject_create_and_add("holders", &ddev->kobj);
548 disk->slave_dir = kobject_create_and_add("slaves", &ddev->kobj);
550 /* No minors to use for partitions */
551 if (!disk_part_scan_enabled(disk))
554 /* No such device (e.g., media were just removed) */
555 if (!get_capacity(disk))
558 bdev = bdget_disk(disk, 0);
562 bdev->bd_invalidated = 1;
563 err = blkdev_get(bdev, FMODE_READ, NULL);
566 blkdev_put(bdev, FMODE_READ);
569 /* announce disk after possible partitions are created */
570 dev_set_uevent_suppress(ddev, 0);
571 kobject_uevent(&ddev->kobj, KOBJ_ADD);
573 /* announce possible partitions */
574 disk_part_iter_init(&piter, disk, 0);
575 while ((part = disk_part_iter_next(&piter)))
576 kobject_uevent(&part_to_dev(part)->kobj, KOBJ_ADD);
577 disk_part_iter_exit(&piter);
581 * add_disk - add partitioning information to kernel list
582 * @disk: per-device partitioning information
584 * This function registers the partitioning information in @disk
587 * FIXME: error handling
589 void add_disk(struct gendisk *disk)
591 struct backing_dev_info *bdi;
595 /* minors == 0 indicates to use ext devt from part0 and should
596 * be accompanied with EXT_DEVT flag. Make sure all
597 * parameters make sense.
599 WARN_ON(disk->minors && !(disk->major || disk->first_minor));
600 WARN_ON(!disk->minors && !(disk->flags & GENHD_FL_EXT_DEVT));
602 disk->flags |= GENHD_FL_UP;
604 retval = blk_alloc_devt(&disk->part0, &devt);
609 disk_to_dev(disk)->devt = devt;
611 /* ->major and ->first_minor aren't supposed to be
612 * dereferenced from here on, but set them just in case.
614 disk->major = MAJOR(devt);
615 disk->first_minor = MINOR(devt);
617 disk_alloc_events(disk);
619 /* Register BDI before referencing it from bdev */
620 bdi = &disk->queue->backing_dev_info;
621 bdi_register_dev(bdi, disk_devt(disk));
623 blk_register_region(disk_devt(disk), disk->minors, NULL,
624 exact_match, exact_lock, disk);
626 blk_register_queue(disk);
629 * Take an extra ref on queue which will be put on disk_release()
630 * so that it sticks around as long as @disk is there.
632 WARN_ON_ONCE(!blk_get_queue(disk->queue));
634 retval = sysfs_create_link(&disk_to_dev(disk)->kobj, &bdi->dev->kobj,
638 disk_add_events(disk);
640 EXPORT_SYMBOL(add_disk);
642 void del_gendisk(struct gendisk *disk)
644 struct disk_part_iter piter;
645 struct hd_struct *part;
647 disk_del_events(disk);
649 /* invalidate stuff */
650 disk_part_iter_init(&piter, disk,
651 DISK_PITER_INCL_EMPTY | DISK_PITER_REVERSE);
652 while ((part = disk_part_iter_next(&piter))) {
653 invalidate_partition(disk, part->partno);
654 delete_partition(disk, part->partno);
656 disk_part_iter_exit(&piter);
658 invalidate_partition(disk, 0);
659 set_capacity(disk, 0);
660 disk->flags &= ~GENHD_FL_UP;
662 sysfs_remove_link(&disk_to_dev(disk)->kobj, "bdi");
663 bdi_unregister(&disk->queue->backing_dev_info);
664 blk_unregister_queue(disk);
665 blk_unregister_region(disk_devt(disk), disk->minors);
667 part_stat_set_all(&disk->part0, 0);
668 disk->part0.stamp = 0;
670 kobject_put(disk->part0.holder_dir);
671 kobject_put(disk->slave_dir);
672 disk->driverfs_dev = NULL;
673 if (!sysfs_deprecated)
674 sysfs_remove_link(block_depr, dev_name(disk_to_dev(disk)));
675 pm_runtime_set_memalloc_noio(disk_to_dev(disk), false);
676 device_del(disk_to_dev(disk));
677 blk_free_devt(disk_to_dev(disk)->devt);
679 EXPORT_SYMBOL(del_gendisk);
682 * get_gendisk - get partitioning information for a given device
683 * @devt: device to get partitioning information for
684 * @partno: returned partition index
686 * This function gets the structure containing partitioning
687 * information for the given device @devt.
689 struct gendisk *get_gendisk(dev_t devt, int *partno)
691 struct gendisk *disk = NULL;
693 if (MAJOR(devt) != BLOCK_EXT_MAJOR) {
694 struct kobject *kobj;
696 kobj = kobj_lookup(bdev_map, devt, partno);
698 disk = dev_to_disk(kobj_to_dev(kobj));
700 struct hd_struct *part;
702 mutex_lock(&ext_devt_mutex);
703 part = idr_find(&ext_devt_idr, blk_mangle_minor(MINOR(devt)));
704 if (part && get_disk(part_to_disk(part))) {
705 *partno = part->partno;
706 disk = part_to_disk(part);
708 mutex_unlock(&ext_devt_mutex);
713 EXPORT_SYMBOL(get_gendisk);
716 * bdget_disk - do bdget() by gendisk and partition number
717 * @disk: gendisk of interest
718 * @partno: partition number
720 * Find partition @partno from @disk, do bdget() on it.
726 * Resulting block_device on success, NULL on failure.
728 struct block_device *bdget_disk(struct gendisk *disk, int partno)
730 struct hd_struct *part;
731 struct block_device *bdev = NULL;
733 part = disk_get_part(disk, partno);
735 bdev = bdget(part_devt(part));
740 EXPORT_SYMBOL(bdget_disk);
743 * print a full list of all partitions - intended for places where the root
744 * filesystem can't be mounted and thus to give the victim some idea of what
747 void __init printk_all_partitions(void)
749 struct class_dev_iter iter;
752 class_dev_iter_init(&iter, &block_class, NULL, &disk_type);
753 while ((dev = class_dev_iter_next(&iter))) {
754 struct gendisk *disk = dev_to_disk(dev);
755 struct disk_part_iter piter;
756 struct hd_struct *part;
757 char name_buf[BDEVNAME_SIZE];
758 char devt_buf[BDEVT_SIZE];
761 * Don't show empty devices or things that have been
764 if (get_capacity(disk) == 0 ||
765 (disk->flags & GENHD_FL_SUPPRESS_PARTITION_INFO))
769 * Note, unlike /proc/partitions, I am showing the
770 * numbers in hex - the same format as the root=
773 disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0);
774 while ((part = disk_part_iter_next(&piter))) {
775 bool is_part0 = part == &disk->part0;
777 printk("%s%s %10llu %s %s", is_part0 ? "" : " ",
778 bdevt_str(part_devt(part), devt_buf),
779 (unsigned long long)part_nr_sects_read(part) >> 1
780 , disk_name(disk, part->partno, name_buf),
781 part->info ? part->info->uuid : "");
783 if (disk->driverfs_dev != NULL &&
784 disk->driverfs_dev->driver != NULL)
785 printk(" driver: %s\n",
786 disk->driverfs_dev->driver->name);
788 printk(" (driver?)\n");
792 disk_part_iter_exit(&piter);
794 class_dev_iter_exit(&iter);
797 #ifdef CONFIG_PROC_FS
799 static void *disk_seqf_start(struct seq_file *seqf, loff_t *pos)
802 struct class_dev_iter *iter;
805 iter = kmalloc(sizeof(*iter), GFP_KERNEL);
807 return ERR_PTR(-ENOMEM);
809 seqf->private = iter;
810 class_dev_iter_init(iter, &block_class, NULL, &disk_type);
812 dev = class_dev_iter_next(iter);
817 return dev_to_disk(dev);
820 static void *disk_seqf_next(struct seq_file *seqf, void *v, loff_t *pos)
825 dev = class_dev_iter_next(seqf->private);
827 return dev_to_disk(dev);
832 static void disk_seqf_stop(struct seq_file *seqf, void *v)
834 struct class_dev_iter *iter = seqf->private;
836 /* stop is called even after start failed :-( */
838 class_dev_iter_exit(iter);
843 static void *show_partition_start(struct seq_file *seqf, loff_t *pos)
847 p = disk_seqf_start(seqf, pos);
848 if (!IS_ERR_OR_NULL(p) && !*pos)
849 seq_puts(seqf, "major minor #blocks name\n\n");
853 static int show_partition(struct seq_file *seqf, void *v)
855 struct gendisk *sgp = v;
856 struct disk_part_iter piter;
857 struct hd_struct *part;
858 char buf[BDEVNAME_SIZE];
860 /* Don't show non-partitionable removeable devices or empty devices */
861 if (!get_capacity(sgp) || (!disk_max_parts(sgp) &&
862 (sgp->flags & GENHD_FL_REMOVABLE)))
864 if (sgp->flags & GENHD_FL_SUPPRESS_PARTITION_INFO)
867 /* show the full disk and all non-0 size partitions of it */
868 disk_part_iter_init(&piter, sgp, DISK_PITER_INCL_PART0);
869 while ((part = disk_part_iter_next(&piter)))
870 seq_printf(seqf, "%4d %7d %10llu %s\n",
871 MAJOR(part_devt(part)), MINOR(part_devt(part)),
872 (unsigned long long)part_nr_sects_read(part) >> 1,
873 disk_name(sgp, part->partno, buf));
874 disk_part_iter_exit(&piter);
879 static const struct seq_operations partitions_op = {
880 .start = show_partition_start,
881 .next = disk_seqf_next,
882 .stop = disk_seqf_stop,
883 .show = show_partition
886 static int partitions_open(struct inode *inode, struct file *file)
888 return seq_open(file, &partitions_op);
891 static const struct file_operations proc_partitions_operations = {
892 .open = partitions_open,
895 .release = seq_release,
900 static struct kobject *base_probe(dev_t devt, int *partno, void *data)
902 if (request_module("block-major-%d-%d", MAJOR(devt), MINOR(devt)) > 0)
903 /* Make old-style 2.4 aliases work */
904 request_module("block-major-%d", MAJOR(devt));
908 static int __init genhd_device_init(void)
912 block_class.dev_kobj = sysfs_dev_block_kobj;
913 error = class_register(&block_class);
916 bdev_map = kobj_map_init(base_probe, &block_class_lock);
919 register_blkdev(BLOCK_EXT_MAJOR, "blkext");
921 /* create top-level block dir */
922 if (!sysfs_deprecated)
923 block_depr = kobject_create_and_add("block", NULL);
927 subsys_initcall(genhd_device_init);
929 static ssize_t disk_range_show(struct device *dev,
930 struct device_attribute *attr, char *buf)
932 struct gendisk *disk = dev_to_disk(dev);
934 return sprintf(buf, "%d\n", disk->minors);
937 static ssize_t disk_ext_range_show(struct device *dev,
938 struct device_attribute *attr, char *buf)
940 struct gendisk *disk = dev_to_disk(dev);
942 return sprintf(buf, "%d\n", disk_max_parts(disk));
945 static ssize_t disk_removable_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",
951 (disk->flags & GENHD_FL_REMOVABLE ? 1 : 0));
954 static ssize_t disk_ro_show(struct device *dev,
955 struct device_attribute *attr, char *buf)
957 struct gendisk *disk = dev_to_disk(dev);
959 return sprintf(buf, "%d\n", get_disk_ro(disk) ? 1 : 0);
962 static ssize_t disk_capability_show(struct device *dev,
963 struct device_attribute *attr, char *buf)
965 struct gendisk *disk = dev_to_disk(dev);
967 return sprintf(buf, "%x\n", disk->flags);
970 static ssize_t disk_alignment_offset_show(struct device *dev,
971 struct device_attribute *attr,
974 struct gendisk *disk = dev_to_disk(dev);
976 return sprintf(buf, "%d\n", queue_alignment_offset(disk->queue));
979 static ssize_t disk_discard_alignment_show(struct device *dev,
980 struct device_attribute *attr,
983 struct gendisk *disk = dev_to_disk(dev);
985 return sprintf(buf, "%d\n", queue_discard_alignment(disk->queue));
988 static DEVICE_ATTR(range, S_IRUGO, disk_range_show, NULL);
989 static DEVICE_ATTR(ext_range, S_IRUGO, disk_ext_range_show, NULL);
990 static DEVICE_ATTR(removable, S_IRUGO, disk_removable_show, NULL);
991 static DEVICE_ATTR(ro, S_IRUGO, disk_ro_show, NULL);
992 static DEVICE_ATTR(size, S_IRUGO, part_size_show, NULL);
993 static DEVICE_ATTR(alignment_offset, S_IRUGO, disk_alignment_offset_show, NULL);
994 static DEVICE_ATTR(discard_alignment, S_IRUGO, disk_discard_alignment_show,
996 static DEVICE_ATTR(capability, S_IRUGO, disk_capability_show, NULL);
997 static DEVICE_ATTR(stat, S_IRUGO, part_stat_show, NULL);
998 static DEVICE_ATTR(inflight, S_IRUGO, part_inflight_show, NULL);
999 #ifdef CONFIG_FAIL_MAKE_REQUEST
1000 static struct device_attribute dev_attr_fail =
1001 __ATTR(make-it-fail, S_IRUGO|S_IWUSR, part_fail_show, part_fail_store);
1003 #ifdef CONFIG_FAIL_IO_TIMEOUT
1004 static struct device_attribute dev_attr_fail_timeout =
1005 __ATTR(io-timeout-fail, S_IRUGO|S_IWUSR, part_timeout_show,
1006 part_timeout_store);
1009 static struct attribute *disk_attrs[] = {
1010 &dev_attr_range.attr,
1011 &dev_attr_ext_range.attr,
1012 &dev_attr_removable.attr,
1014 &dev_attr_size.attr,
1015 &dev_attr_alignment_offset.attr,
1016 &dev_attr_discard_alignment.attr,
1017 &dev_attr_capability.attr,
1018 &dev_attr_stat.attr,
1019 &dev_attr_inflight.attr,
1020 #ifdef CONFIG_FAIL_MAKE_REQUEST
1021 &dev_attr_fail.attr,
1023 #ifdef CONFIG_FAIL_IO_TIMEOUT
1024 &dev_attr_fail_timeout.attr,
1029 static struct attribute_group disk_attr_group = {
1030 .attrs = disk_attrs,
1033 static const struct attribute_group *disk_attr_groups[] = {
1039 * disk_replace_part_tbl - replace disk->part_tbl in RCU-safe way
1040 * @disk: disk to replace part_tbl for
1041 * @new_ptbl: new part_tbl to install
1043 * Replace disk->part_tbl with @new_ptbl in RCU-safe way. The
1044 * original ptbl is freed using RCU callback.
1047 * Matching bd_mutx locked.
1049 static void disk_replace_part_tbl(struct gendisk *disk,
1050 struct disk_part_tbl *new_ptbl)
1052 struct disk_part_tbl *old_ptbl = disk->part_tbl;
1054 rcu_assign_pointer(disk->part_tbl, new_ptbl);
1057 rcu_assign_pointer(old_ptbl->last_lookup, NULL);
1058 kfree_rcu(old_ptbl, rcu_head);
1063 * disk_expand_part_tbl - expand disk->part_tbl
1064 * @disk: disk to expand part_tbl for
1065 * @partno: expand such that this partno can fit in
1067 * Expand disk->part_tbl such that @partno can fit in. disk->part_tbl
1068 * uses RCU to allow unlocked dereferencing for stats and other stuff.
1071 * Matching bd_mutex locked, might sleep.
1074 * 0 on success, -errno on failure.
1076 int disk_expand_part_tbl(struct gendisk *disk, int partno)
1078 struct disk_part_tbl *old_ptbl = disk->part_tbl;
1079 struct disk_part_tbl *new_ptbl;
1080 int len = old_ptbl ? old_ptbl->len : 0;
1081 int target = partno + 1;
1085 /* disk_max_parts() is zero during initialization, ignore if so */
1086 if (disk_max_parts(disk) && target > disk_max_parts(disk))
1092 size = sizeof(*new_ptbl) + target * sizeof(new_ptbl->part[0]);
1093 new_ptbl = kzalloc_node(size, GFP_KERNEL, disk->node_id);
1097 new_ptbl->len = target;
1099 for (i = 0; i < len; i++)
1100 rcu_assign_pointer(new_ptbl->part[i], old_ptbl->part[i]);
1102 disk_replace_part_tbl(disk, new_ptbl);
1106 static void disk_release(struct device *dev)
1108 struct gendisk *disk = dev_to_disk(dev);
1110 disk_release_events(disk);
1111 kfree(disk->random);
1112 disk_replace_part_tbl(disk, NULL);
1113 free_part_stats(&disk->part0);
1114 free_part_info(&disk->part0);
1116 blk_put_queue(disk->queue);
1119 struct class block_class = {
1123 static char *block_devnode(struct device *dev, umode_t *mode)
1125 struct gendisk *disk = dev_to_disk(dev);
1128 return disk->devnode(disk, mode);
1132 static struct device_type disk_type = {
1134 .groups = disk_attr_groups,
1135 .release = disk_release,
1136 .devnode = block_devnode,
1139 #ifdef CONFIG_PROC_FS
1141 * aggregate disk stat collector. Uses the same stats that the sysfs
1142 * entries do, above, but makes them available through one seq_file.
1144 * The output looks suspiciously like /proc/partitions with a bunch of
1147 static int diskstats_show(struct seq_file *seqf, void *v)
1149 struct gendisk *gp = v;
1150 struct disk_part_iter piter;
1151 struct hd_struct *hd;
1152 char buf[BDEVNAME_SIZE];
1156 if (&disk_to_dev(gp)->kobj.entry == block_class.devices.next)
1157 seq_puts(seqf, "major minor name"
1158 " rio rmerge rsect ruse wio wmerge "
1159 "wsect wuse running use aveq"
1163 disk_part_iter_init(&piter, gp, DISK_PITER_INCL_EMPTY_PART0);
1164 while ((hd = disk_part_iter_next(&piter))) {
1165 cpu = part_stat_lock();
1166 part_round_stats(cpu, hd);
1168 seq_printf(seqf, "%4d %7d %s %lu %lu %lu "
1169 "%u %lu %lu %lu %u %u %u %u\n",
1170 MAJOR(part_devt(hd)), MINOR(part_devt(hd)),
1171 disk_name(gp, hd->partno, buf),
1172 part_stat_read(hd, ios[READ]),
1173 part_stat_read(hd, merges[READ]),
1174 part_stat_read(hd, sectors[READ]),
1175 jiffies_to_msecs(part_stat_read(hd, ticks[READ])),
1176 part_stat_read(hd, ios[WRITE]),
1177 part_stat_read(hd, merges[WRITE]),
1178 part_stat_read(hd, sectors[WRITE]),
1179 jiffies_to_msecs(part_stat_read(hd, ticks[WRITE])),
1181 jiffies_to_msecs(part_stat_read(hd, io_ticks)),
1182 jiffies_to_msecs(part_stat_read(hd, time_in_queue))
1185 disk_part_iter_exit(&piter);
1190 static const struct seq_operations diskstats_op = {
1191 .start = disk_seqf_start,
1192 .next = disk_seqf_next,
1193 .stop = disk_seqf_stop,
1194 .show = diskstats_show
1197 static int diskstats_open(struct inode *inode, struct file *file)
1199 return seq_open(file, &diskstats_op);
1202 static const struct file_operations proc_diskstats_operations = {
1203 .open = diskstats_open,
1205 .llseek = seq_lseek,
1206 .release = seq_release,
1209 static int __init proc_genhd_init(void)
1211 proc_create("diskstats", 0, NULL, &proc_diskstats_operations);
1212 proc_create("partitions", 0, NULL, &proc_partitions_operations);
1215 module_init(proc_genhd_init);
1216 #endif /* CONFIG_PROC_FS */
1218 dev_t blk_lookup_devt(const char *name, int partno)
1220 dev_t devt = MKDEV(0, 0);
1221 struct class_dev_iter iter;
1224 class_dev_iter_init(&iter, &block_class, NULL, &disk_type);
1225 while ((dev = class_dev_iter_next(&iter))) {
1226 struct gendisk *disk = dev_to_disk(dev);
1227 struct hd_struct *part;
1229 if (strcmp(dev_name(dev), name))
1232 if (partno < disk->minors) {
1233 /* We need to return the right devno, even
1234 * if the partition doesn't exist yet.
1236 devt = MKDEV(MAJOR(dev->devt),
1237 MINOR(dev->devt) + partno);
1240 part = disk_get_part(disk, partno);
1242 devt = part_devt(part);
1243 disk_put_part(part);
1246 disk_put_part(part);
1248 class_dev_iter_exit(&iter);
1251 EXPORT_SYMBOL(blk_lookup_devt);
1253 struct gendisk *alloc_disk(int minors)
1255 return alloc_disk_node(minors, NUMA_NO_NODE);
1257 EXPORT_SYMBOL(alloc_disk);
1259 struct gendisk *alloc_disk_node(int minors, int node_id)
1261 struct gendisk *disk;
1263 disk = kmalloc_node(sizeof(struct gendisk),
1264 GFP_KERNEL | __GFP_ZERO, node_id);
1266 if (!init_part_stats(&disk->part0)) {
1270 disk->node_id = node_id;
1271 if (disk_expand_part_tbl(disk, 0)) {
1272 free_part_stats(&disk->part0);
1276 disk->part_tbl->part[0] = &disk->part0;
1279 * set_capacity() and get_capacity() currently don't use
1280 * seqcounter to read/update the part0->nr_sects. Still init
1281 * the counter as we can read the sectors in IO submission
1282 * patch using seqence counters.
1284 * TODO: Ideally set_capacity() and get_capacity() should be
1285 * converted to make use of bd_mutex and sequence counters.
1287 seqcount_init(&disk->part0.nr_sects_seq);
1288 hd_ref_init(&disk->part0);
1290 disk->minors = minors;
1291 rand_initialize_disk(disk);
1292 disk_to_dev(disk)->class = &block_class;
1293 disk_to_dev(disk)->type = &disk_type;
1294 device_initialize(disk_to_dev(disk));
1298 EXPORT_SYMBOL(alloc_disk_node);
1300 struct kobject *get_disk(struct gendisk *disk)
1302 struct module *owner;
1303 struct kobject *kobj;
1307 owner = disk->fops->owner;
1308 if (owner && !try_module_get(owner))
1310 kobj = kobject_get(&disk_to_dev(disk)->kobj);
1319 EXPORT_SYMBOL(get_disk);
1321 void put_disk(struct gendisk *disk)
1324 kobject_put(&disk_to_dev(disk)->kobj);
1327 EXPORT_SYMBOL(put_disk);
1329 static void set_disk_ro_uevent(struct gendisk *gd, int ro)
1331 char event[] = "DISK_RO=1";
1332 char *envp[] = { event, NULL };
1336 kobject_uevent_env(&disk_to_dev(gd)->kobj, KOBJ_CHANGE, envp);
1339 void set_device_ro(struct block_device *bdev, int flag)
1341 bdev->bd_part->policy = flag;
1344 EXPORT_SYMBOL(set_device_ro);
1346 void set_disk_ro(struct gendisk *disk, int flag)
1348 struct disk_part_iter piter;
1349 struct hd_struct *part;
1351 if (disk->part0.policy != flag) {
1352 set_disk_ro_uevent(disk, flag);
1353 disk->part0.policy = flag;
1356 disk_part_iter_init(&piter, disk, DISK_PITER_INCL_EMPTY);
1357 while ((part = disk_part_iter_next(&piter)))
1358 part->policy = flag;
1359 disk_part_iter_exit(&piter);
1362 EXPORT_SYMBOL(set_disk_ro);
1364 int bdev_read_only(struct block_device *bdev)
1368 return bdev->bd_part->policy;
1371 EXPORT_SYMBOL(bdev_read_only);
1373 int invalidate_partition(struct gendisk *disk, int partno)
1376 struct block_device *bdev = bdget_disk(disk, partno);
1379 res = __invalidate_device(bdev, true);
1385 EXPORT_SYMBOL(invalidate_partition);
1388 * Disk events - monitor disk events like media change and eject request.
1390 struct disk_events {
1391 struct list_head node; /* all disk_event's */
1392 struct gendisk *disk; /* the associated disk */
1395 struct mutex block_mutex; /* protects blocking */
1396 int block; /* event blocking depth */
1397 unsigned int pending; /* events already sent out */
1398 unsigned int clearing; /* events being cleared */
1400 long poll_msecs; /* interval, -1 for default */
1401 struct delayed_work dwork;
1404 static const char *disk_events_strs[] = {
1405 [ilog2(DISK_EVENT_MEDIA_CHANGE)] = "media_change",
1406 [ilog2(DISK_EVENT_EJECT_REQUEST)] = "eject_request",
1409 static char *disk_uevents[] = {
1410 [ilog2(DISK_EVENT_MEDIA_CHANGE)] = "DISK_MEDIA_CHANGE=1",
1411 [ilog2(DISK_EVENT_EJECT_REQUEST)] = "DISK_EJECT_REQUEST=1",
1414 /* list of all disk_events */
1415 static DEFINE_MUTEX(disk_events_mutex);
1416 static LIST_HEAD(disk_events);
1418 /* disable in-kernel polling by default */
1419 static unsigned long disk_events_dfl_poll_msecs = 0;
1421 static unsigned long disk_events_poll_jiffies(struct gendisk *disk)
1423 struct disk_events *ev = disk->ev;
1424 long intv_msecs = 0;
1427 * If device-specific poll interval is set, always use it. If
1428 * the default is being used, poll iff there are events which
1429 * can't be monitored asynchronously.
1431 if (ev->poll_msecs >= 0)
1432 intv_msecs = ev->poll_msecs;
1433 else if (disk->events & ~disk->async_events)
1434 intv_msecs = disk_events_dfl_poll_msecs;
1436 return msecs_to_jiffies(intv_msecs);
1440 * disk_block_events - block and flush disk event checking
1441 * @disk: disk to block events for
1443 * On return from this function, it is guaranteed that event checking
1444 * isn't in progress and won't happen until unblocked by
1445 * disk_unblock_events(). Events blocking is counted and the actual
1446 * unblocking happens after the matching number of unblocks are done.
1448 * Note that this intentionally does not block event checking from
1449 * disk_clear_events().
1454 void disk_block_events(struct gendisk *disk)
1456 struct disk_events *ev = disk->ev;
1457 unsigned long flags;
1464 * Outer mutex ensures that the first blocker completes canceling
1465 * the event work before further blockers are allowed to finish.
1467 mutex_lock(&ev->block_mutex);
1469 spin_lock_irqsave(&ev->lock, flags);
1470 cancel = !ev->block++;
1471 spin_unlock_irqrestore(&ev->lock, flags);
1474 cancel_delayed_work_sync(&disk->ev->dwork);
1476 mutex_unlock(&ev->block_mutex);
1479 static void __disk_unblock_events(struct gendisk *disk, bool check_now)
1481 struct disk_events *ev = disk->ev;
1483 unsigned long flags;
1485 spin_lock_irqsave(&ev->lock, flags);
1487 if (WARN_ON_ONCE(ev->block <= 0))
1494 * Not exactly a latency critical operation, set poll timer
1495 * slack to 25% and kick event check.
1497 intv = disk_events_poll_jiffies(disk);
1498 set_timer_slack(&ev->dwork.timer, intv / 4);
1500 queue_delayed_work(system_freezable_wq, &ev->dwork, 0);
1502 queue_delayed_work(system_freezable_wq, &ev->dwork, intv);
1504 spin_unlock_irqrestore(&ev->lock, flags);
1508 * disk_unblock_events - unblock disk event checking
1509 * @disk: disk to unblock events for
1511 * Undo disk_block_events(). When the block count reaches zero, it
1512 * starts events polling if configured.
1515 * Don't care. Safe to call from irq context.
1517 void disk_unblock_events(struct gendisk *disk)
1520 __disk_unblock_events(disk, false);
1524 * disk_flush_events - schedule immediate event checking and flushing
1525 * @disk: disk to check and flush events for
1526 * @mask: events to flush
1528 * Schedule immediate event checking on @disk if not blocked. Events in
1529 * @mask are scheduled to be cleared from the driver. Note that this
1530 * doesn't clear the events from @disk->ev.
1533 * If @mask is non-zero must be called with bdev->bd_mutex held.
1535 void disk_flush_events(struct gendisk *disk, unsigned int mask)
1537 struct disk_events *ev = disk->ev;
1542 spin_lock_irq(&ev->lock);
1543 ev->clearing |= mask;
1545 mod_delayed_work(system_freezable_wq, &ev->dwork, 0);
1546 spin_unlock_irq(&ev->lock);
1550 * disk_clear_events - synchronously check, clear and return pending events
1551 * @disk: disk to fetch and clear events from
1552 * @mask: mask of events to be fetched and clearted
1554 * Disk events are synchronously checked and pending events in @mask
1555 * are cleared and returned. This ignores the block count.
1560 unsigned int disk_clear_events(struct gendisk *disk, unsigned int mask)
1562 const struct block_device_operations *bdops = disk->fops;
1563 struct disk_events *ev = disk->ev;
1564 unsigned int pending;
1565 unsigned int clearing = mask;
1568 /* for drivers still using the old ->media_changed method */
1569 if ((mask & DISK_EVENT_MEDIA_CHANGE) &&
1570 bdops->media_changed && bdops->media_changed(disk))
1571 return DISK_EVENT_MEDIA_CHANGE;
1575 disk_block_events(disk);
1578 * store the union of mask and ev->clearing on the stack so that the
1579 * race with disk_flush_events does not cause ambiguity (ev->clearing
1580 * can still be modified even if events are blocked).
1582 spin_lock_irq(&ev->lock);
1583 clearing |= ev->clearing;
1585 spin_unlock_irq(&ev->lock);
1587 disk_check_events(ev, &clearing);
1589 * if ev->clearing is not 0, the disk_flush_events got called in the
1590 * middle of this function, so we want to run the workfn without delay.
1592 __disk_unblock_events(disk, ev->clearing ? true : false);
1594 /* then, fetch and clear pending events */
1595 spin_lock_irq(&ev->lock);
1596 pending = ev->pending & mask;
1597 ev->pending &= ~mask;
1598 spin_unlock_irq(&ev->lock);
1599 WARN_ON_ONCE(clearing & mask);
1605 * Separate this part out so that a different pointer for clearing_ptr can be
1606 * passed in for disk_clear_events.
1608 static void disk_events_workfn(struct work_struct *work)
1610 struct delayed_work *dwork = to_delayed_work(work);
1611 struct disk_events *ev = container_of(dwork, struct disk_events, dwork);
1613 disk_check_events(ev, &ev->clearing);
1616 static void disk_check_events(struct disk_events *ev,
1617 unsigned int *clearing_ptr)
1619 struct gendisk *disk = ev->disk;
1620 char *envp[ARRAY_SIZE(disk_uevents) + 1] = { };
1621 unsigned int clearing = *clearing_ptr;
1622 unsigned int events;
1624 int nr_events = 0, i;
1627 events = disk->fops->check_events(disk, clearing);
1629 /* accumulate pending events and schedule next poll if necessary */
1630 spin_lock_irq(&ev->lock);
1632 events &= ~ev->pending;
1633 ev->pending |= events;
1634 *clearing_ptr &= ~clearing;
1636 intv = disk_events_poll_jiffies(disk);
1637 if (!ev->block && intv)
1638 queue_delayed_work(system_freezable_wq, &ev->dwork, intv);
1640 spin_unlock_irq(&ev->lock);
1643 * Tell userland about new events. Only the events listed in
1644 * @disk->events are reported. Unlisted events are processed the
1645 * same internally but never get reported to userland.
1647 for (i = 0; i < ARRAY_SIZE(disk_uevents); i++)
1648 if (events & disk->events & (1 << i))
1649 envp[nr_events++] = disk_uevents[i];
1652 kobject_uevent_env(&disk_to_dev(disk)->kobj, KOBJ_CHANGE, envp);
1656 * A disk events enabled device has the following sysfs nodes under
1657 * its /sys/block/X/ directory.
1659 * events : list of all supported events
1660 * events_async : list of events which can be detected w/o polling
1661 * events_poll_msecs : polling interval, 0: disable, -1: system default
1663 static ssize_t __disk_events_show(unsigned int events, char *buf)
1665 const char *delim = "";
1669 for (i = 0; i < ARRAY_SIZE(disk_events_strs); i++)
1670 if (events & (1 << i)) {
1671 pos += sprintf(buf + pos, "%s%s",
1672 delim, disk_events_strs[i]);
1676 pos += sprintf(buf + pos, "\n");
1680 static ssize_t disk_events_show(struct device *dev,
1681 struct device_attribute *attr, char *buf)
1683 struct gendisk *disk = dev_to_disk(dev);
1685 return __disk_events_show(disk->events, buf);
1688 static ssize_t disk_events_async_show(struct device *dev,
1689 struct device_attribute *attr, char *buf)
1691 struct gendisk *disk = dev_to_disk(dev);
1693 return __disk_events_show(disk->async_events, buf);
1696 static ssize_t disk_events_poll_msecs_show(struct device *dev,
1697 struct device_attribute *attr,
1700 struct gendisk *disk = dev_to_disk(dev);
1702 return sprintf(buf, "%ld\n", disk->ev->poll_msecs);
1705 static ssize_t disk_events_poll_msecs_store(struct device *dev,
1706 struct device_attribute *attr,
1707 const char *buf, size_t count)
1709 struct gendisk *disk = dev_to_disk(dev);
1712 if (!count || !sscanf(buf, "%ld", &intv))
1715 if (intv < 0 && intv != -1)
1718 disk_block_events(disk);
1719 disk->ev->poll_msecs = intv;
1720 __disk_unblock_events(disk, true);
1725 static const DEVICE_ATTR(events, S_IRUGO, disk_events_show, NULL);
1726 static const DEVICE_ATTR(events_async, S_IRUGO, disk_events_async_show, NULL);
1727 static const DEVICE_ATTR(events_poll_msecs, S_IRUGO|S_IWUSR,
1728 disk_events_poll_msecs_show,
1729 disk_events_poll_msecs_store);
1731 static const struct attribute *disk_events_attrs[] = {
1732 &dev_attr_events.attr,
1733 &dev_attr_events_async.attr,
1734 &dev_attr_events_poll_msecs.attr,
1739 * The default polling interval can be specified by the kernel
1740 * parameter block.events_dfl_poll_msecs which defaults to 0
1741 * (disable). This can also be modified runtime by writing to
1742 * /sys/module/block/events_dfl_poll_msecs.
1744 static int disk_events_set_dfl_poll_msecs(const char *val,
1745 const struct kernel_param *kp)
1747 struct disk_events *ev;
1750 ret = param_set_ulong(val, kp);
1754 mutex_lock(&disk_events_mutex);
1756 list_for_each_entry(ev, &disk_events, node)
1757 disk_flush_events(ev->disk, 0);
1759 mutex_unlock(&disk_events_mutex);
1764 static const struct kernel_param_ops disk_events_dfl_poll_msecs_param_ops = {
1765 .set = disk_events_set_dfl_poll_msecs,
1766 .get = param_get_ulong,
1769 #undef MODULE_PARAM_PREFIX
1770 #define MODULE_PARAM_PREFIX "block."
1772 module_param_cb(events_dfl_poll_msecs, &disk_events_dfl_poll_msecs_param_ops,
1773 &disk_events_dfl_poll_msecs, 0644);
1776 * disk_{alloc|add|del|release}_events - initialize and destroy disk_events.
1778 static void disk_alloc_events(struct gendisk *disk)
1780 struct disk_events *ev;
1782 if (!disk->fops->check_events)
1785 ev = kzalloc(sizeof(*ev), GFP_KERNEL);
1787 pr_warn("%s: failed to initialize events\n", disk->disk_name);
1791 INIT_LIST_HEAD(&ev->node);
1793 spin_lock_init(&ev->lock);
1794 mutex_init(&ev->block_mutex);
1796 ev->poll_msecs = -1;
1797 INIT_DELAYED_WORK(&ev->dwork, disk_events_workfn);
1802 static void disk_add_events(struct gendisk *disk)
1807 /* FIXME: error handling */
1808 if (sysfs_create_files(&disk_to_dev(disk)->kobj, disk_events_attrs) < 0)
1809 pr_warn("%s: failed to create sysfs files for events\n",
1812 mutex_lock(&disk_events_mutex);
1813 list_add_tail(&disk->ev->node, &disk_events);
1814 mutex_unlock(&disk_events_mutex);
1817 * Block count is initialized to 1 and the following initial
1818 * unblock kicks it into action.
1820 __disk_unblock_events(disk, true);
1823 static void disk_del_events(struct gendisk *disk)
1828 disk_block_events(disk);
1830 mutex_lock(&disk_events_mutex);
1831 list_del_init(&disk->ev->node);
1832 mutex_unlock(&disk_events_mutex);
1834 sysfs_remove_files(&disk_to_dev(disk)->kobj, disk_events_attrs);
1837 static void disk_release_events(struct gendisk *disk)
1839 /* the block count should be 1 from disk_del_events() */
1840 WARN_ON_ONCE(disk->ev && disk->ev->block != 1);