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/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>
27 static DEFINE_MUTEX(block_class_lock
);
28 struct kobject
*block_depr
;
30 /* for extended dynamic devt allocation, currently only one major is used */
31 #define NR_EXT_DEVT (1 << MINORBITS)
33 /* For extended devt allocation. ext_devt_lock prevents look up
34 * results from going away underneath its user.
36 static DEFINE_SPINLOCK(ext_devt_lock
);
37 static DEFINE_IDR(ext_devt_idr
);
39 static const struct device_type disk_type
;
41 static void disk_check_events(struct disk_events
*ev
,
42 unsigned int *clearing_ptr
);
43 static void disk_alloc_events(struct gendisk
*disk
);
44 static void disk_add_events(struct gendisk
*disk
);
45 static void disk_del_events(struct gendisk
*disk
);
46 static void disk_release_events(struct gendisk
*disk
);
49 * disk_get_part - get partition
50 * @disk: disk to look partition from
51 * @partno: partition number
53 * Look for partition @partno from @disk. If found, increment
54 * reference count and return it.
60 * Pointer to the found partition on success, NULL if not found.
62 struct hd_struct
*disk_get_part(struct gendisk
*disk
, int partno
)
64 struct hd_struct
*part
= NULL
;
65 struct disk_part_tbl
*ptbl
;
67 if (unlikely(partno
< 0))
72 ptbl
= rcu_dereference(disk
->part_tbl
);
73 if (likely(partno
< ptbl
->len
)) {
74 part
= rcu_dereference(ptbl
->part
[partno
]);
76 get_device(part_to_dev(part
));
83 EXPORT_SYMBOL_GPL(disk_get_part
);
86 * disk_part_iter_init - initialize partition iterator
87 * @piter: iterator to initialize
88 * @disk: disk to iterate over
89 * @flags: DISK_PITER_* flags
91 * Initialize @piter so that it iterates over partitions of @disk.
96 void disk_part_iter_init(struct disk_part_iter
*piter
, struct gendisk
*disk
,
99 struct disk_part_tbl
*ptbl
;
102 ptbl
= rcu_dereference(disk
->part_tbl
);
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
))
114 piter
->flags
= flags
;
118 EXPORT_SYMBOL_GPL(disk_part_iter_init
);
121 * disk_part_iter_next - proceed iterator to the next partition and return it
122 * @piter: iterator of interest
124 * Proceed @piter to the next partition and return it.
129 struct hd_struct
*disk_part_iter_next(struct disk_part_iter
*piter
)
131 struct disk_part_tbl
*ptbl
;
134 /* put the last partition */
135 disk_put_part(piter
->part
);
140 ptbl
= rcu_dereference(piter
->disk
->part_tbl
);
142 /* determine iteration parameters */
143 if (piter
->flags
& DISK_PITER_REVERSE
) {
145 if (piter
->flags
& (DISK_PITER_INCL_PART0
|
146 DISK_PITER_INCL_EMPTY_PART0
))
155 /* iterate to the next partition */
156 for (; piter
->idx
!= end
; piter
->idx
+= inc
) {
157 struct hd_struct
*part
;
159 part
= rcu_dereference(ptbl
->part
[piter
->idx
]);
162 if (!part_nr_sects_read(part
) &&
163 !(piter
->flags
& DISK_PITER_INCL_EMPTY
) &&
164 !(piter
->flags
& DISK_PITER_INCL_EMPTY_PART0
&&
168 get_device(part_to_dev(part
));
178 EXPORT_SYMBOL_GPL(disk_part_iter_next
);
181 * disk_part_iter_exit - finish up partition iteration
182 * @piter: iter of interest
184 * Called when iteration is over. Cleans up @piter.
189 void disk_part_iter_exit(struct disk_part_iter
*piter
)
191 disk_put_part(piter
->part
);
194 EXPORT_SYMBOL_GPL(disk_part_iter_exit
);
196 static inline int sector_in_part(struct hd_struct
*part
, sector_t sector
)
198 return part
->start_sect
<= sector
&&
199 sector
< part
->start_sect
+ part_nr_sects_read(part
);
203 * disk_map_sector_rcu - map sector to partition
204 * @disk: gendisk of interest
205 * @sector: sector to map
207 * Find out which partition @sector maps to on @disk. This is
208 * primarily used for stats accounting.
211 * RCU read locked. The returned partition pointer is valid only
212 * while preemption is disabled.
215 * Found partition on success, part0 is returned if no partition matches
217 struct hd_struct
*disk_map_sector_rcu(struct gendisk
*disk
, sector_t sector
)
219 struct disk_part_tbl
*ptbl
;
220 struct hd_struct
*part
;
223 ptbl
= rcu_dereference(disk
->part_tbl
);
225 part
= rcu_dereference(ptbl
->last_lookup
);
226 if (part
&& sector_in_part(part
, sector
))
229 for (i
= 1; i
< ptbl
->len
; i
++) {
230 part
= rcu_dereference(ptbl
->part
[i
]);
232 if (part
&& sector_in_part(part
, sector
)) {
233 rcu_assign_pointer(ptbl
->last_lookup
, part
);
239 EXPORT_SYMBOL_GPL(disk_map_sector_rcu
);
242 * Can be deleted altogether. Later.
245 #define BLKDEV_MAJOR_HASH_SIZE 255
246 static struct blk_major_name
{
247 struct blk_major_name
*next
;
250 } *major_names
[BLKDEV_MAJOR_HASH_SIZE
];
252 /* index in the above - for now: assume no multimajor ranges */
253 static inline int major_to_index(unsigned major
)
255 return major
% BLKDEV_MAJOR_HASH_SIZE
;
258 #ifdef CONFIG_PROC_FS
259 void blkdev_show(struct seq_file
*seqf
, off_t offset
)
261 struct blk_major_name
*dp
;
263 mutex_lock(&block_class_lock
);
264 for (dp
= major_names
[major_to_index(offset
)]; dp
; dp
= dp
->next
)
265 if (dp
->major
== offset
)
266 seq_printf(seqf
, "%3d %s\n", dp
->major
, dp
->name
);
267 mutex_unlock(&block_class_lock
);
269 #endif /* CONFIG_PROC_FS */
272 * register_blkdev - register a new block device
274 * @major: the requested major device number [1..255]. If @major = 0, try to
275 * allocate any unused major number.
276 * @name: the name of the new block device as a zero terminated string
278 * The @name must be unique within the system.
280 * The return value depends on the @major input parameter:
282 * - if a major device number was requested in range [1..255] then the
283 * function returns zero on success, or a negative error code
284 * - if any unused major number was requested with @major = 0 parameter
285 * then the return value is the allocated major number in range
286 * [1..255] or a negative error code otherwise
288 int register_blkdev(unsigned int major
, const char *name
)
290 struct blk_major_name
**n
, *p
;
293 mutex_lock(&block_class_lock
);
297 for (index
= ARRAY_SIZE(major_names
)-1; index
> 0; index
--) {
298 if (major_names
[index
] == NULL
)
303 printk("register_blkdev: failed to get major for %s\n",
312 if (major
>= BLKDEV_MAJOR_MAX
) {
313 pr_err("register_blkdev: major requested (%d) is greater than the maximum (%d) for %s\n",
314 major
, BLKDEV_MAJOR_MAX
, name
);
320 p
= kmalloc(sizeof(struct blk_major_name
), GFP_KERNEL
);
327 strlcpy(p
->name
, name
, sizeof(p
->name
));
329 index
= major_to_index(major
);
331 for (n
= &major_names
[index
]; *n
; n
= &(*n
)->next
) {
332 if ((*n
)->major
== major
)
341 printk("register_blkdev: cannot get major %d for %s\n",
346 mutex_unlock(&block_class_lock
);
350 EXPORT_SYMBOL(register_blkdev
);
352 void unregister_blkdev(unsigned int major
, const char *name
)
354 struct blk_major_name
**n
;
355 struct blk_major_name
*p
= NULL
;
356 int index
= major_to_index(major
);
358 mutex_lock(&block_class_lock
);
359 for (n
= &major_names
[index
]; *n
; n
= &(*n
)->next
)
360 if ((*n
)->major
== major
)
362 if (!*n
|| strcmp((*n
)->name
, name
)) {
368 mutex_unlock(&block_class_lock
);
372 EXPORT_SYMBOL(unregister_blkdev
);
374 static struct kobj_map
*bdev_map
;
377 * blk_mangle_minor - scatter minor numbers apart
378 * @minor: minor number to mangle
380 * Scatter consecutively allocated @minor number apart if MANGLE_DEVT
381 * is enabled. Mangling twice gives the original value.
389 static int blk_mangle_minor(int minor
)
391 #ifdef CONFIG_DEBUG_BLOCK_EXT_DEVT
394 for (i
= 0; i
< MINORBITS
/ 2; i
++) {
395 int low
= minor
& (1 << i
);
396 int high
= minor
& (1 << (MINORBITS
- 1 - i
));
397 int distance
= MINORBITS
- 1 - 2 * i
;
399 minor
^= low
| high
; /* clear both bits */
400 low
<<= distance
; /* swap the positions */
402 minor
|= low
| high
; /* and set */
409 * blk_alloc_devt - allocate a dev_t for a partition
410 * @part: partition to allocate dev_t for
411 * @devt: out parameter for resulting dev_t
413 * Allocate a dev_t for block device.
416 * 0 on success, allocated dev_t is returned in *@devt. -errno on
422 int blk_alloc_devt(struct hd_struct
*part
, dev_t
*devt
)
424 struct gendisk
*disk
= part_to_disk(part
);
427 /* in consecutive minor range? */
428 if (part
->partno
< disk
->minors
) {
429 *devt
= MKDEV(disk
->major
, disk
->first_minor
+ part
->partno
);
433 /* allocate ext devt */
434 idr_preload(GFP_KERNEL
);
436 spin_lock_bh(&ext_devt_lock
);
437 idx
= idr_alloc(&ext_devt_idr
, part
, 0, NR_EXT_DEVT
, GFP_NOWAIT
);
438 spin_unlock_bh(&ext_devt_lock
);
442 return idx
== -ENOSPC
? -EBUSY
: idx
;
444 *devt
= MKDEV(BLOCK_EXT_MAJOR
, blk_mangle_minor(idx
));
449 * blk_free_devt - free a dev_t
450 * @devt: dev_t to free
452 * Free @devt which was allocated using blk_alloc_devt().
457 void blk_free_devt(dev_t devt
)
459 if (devt
== MKDEV(0, 0))
462 if (MAJOR(devt
) == BLOCK_EXT_MAJOR
) {
463 spin_lock_bh(&ext_devt_lock
);
464 idr_remove(&ext_devt_idr
, blk_mangle_minor(MINOR(devt
)));
465 spin_unlock_bh(&ext_devt_lock
);
469 static char *bdevt_str(dev_t devt
, char *buf
)
471 if (MAJOR(devt
) <= 0xff && MINOR(devt
) <= 0xff) {
472 char tbuf
[BDEVT_SIZE
];
473 snprintf(tbuf
, BDEVT_SIZE
, "%02x%02x", MAJOR(devt
), MINOR(devt
));
474 snprintf(buf
, BDEVT_SIZE
, "%-9s", tbuf
);
476 snprintf(buf
, BDEVT_SIZE
, "%03x:%05x", MAJOR(devt
), MINOR(devt
));
482 * Register device numbers dev..(dev+range-1)
483 * range must be nonzero
484 * The hash chain is sorted on range, so that subranges can override.
486 void blk_register_region(dev_t devt
, unsigned long range
, struct module
*module
,
487 struct kobject
*(*probe
)(dev_t
, int *, void *),
488 int (*lock
)(dev_t
, void *), void *data
)
490 kobj_map(bdev_map
, devt
, range
, module
, probe
, lock
, data
);
493 EXPORT_SYMBOL(blk_register_region
);
495 void blk_unregister_region(dev_t devt
, unsigned long range
)
497 kobj_unmap(bdev_map
, devt
, range
);
500 EXPORT_SYMBOL(blk_unregister_region
);
502 static struct kobject
*exact_match(dev_t devt
, int *partno
, void *data
)
504 struct gendisk
*p
= data
;
506 return &disk_to_dev(p
)->kobj
;
509 static int exact_lock(dev_t devt
, void *data
)
511 struct gendisk
*p
= data
;
518 static void register_disk(struct device
*parent
, struct gendisk
*disk
)
520 struct device
*ddev
= disk_to_dev(disk
);
521 struct block_device
*bdev
;
522 struct disk_part_iter piter
;
523 struct hd_struct
*part
;
526 ddev
->parent
= parent
;
528 dev_set_name(ddev
, "%s", disk
->disk_name
);
530 /* delay uevents, until we scanned partition table */
531 dev_set_uevent_suppress(ddev
, 1);
533 if (device_add(ddev
))
535 if (!sysfs_deprecated
) {
536 err
= sysfs_create_link(block_depr
, &ddev
->kobj
,
537 kobject_name(&ddev
->kobj
));
545 * avoid probable deadlock caused by allocating memory with
546 * GFP_KERNEL in runtime_resume callback of its all ancestor
549 pm_runtime_set_memalloc_noio(ddev
, true);
551 disk
->part0
.holder_dir
= kobject_create_and_add("holders", &ddev
->kobj
);
552 disk
->slave_dir
= kobject_create_and_add("slaves", &ddev
->kobj
);
554 /* No minors to use for partitions */
555 if (!disk_part_scan_enabled(disk
))
558 /* No such device (e.g., media were just removed) */
559 if (!get_capacity(disk
))
562 bdev
= bdget_disk(disk
, 0);
566 bdev
->bd_invalidated
= 1;
567 err
= blkdev_get(bdev
, FMODE_READ
, NULL
);
570 blkdev_put(bdev
, FMODE_READ
);
573 /* announce disk after possible partitions are created */
574 dev_set_uevent_suppress(ddev
, 0);
575 kobject_uevent(&ddev
->kobj
, KOBJ_ADD
);
577 /* announce possible partitions */
578 disk_part_iter_init(&piter
, disk
, 0);
579 while ((part
= disk_part_iter_next(&piter
)))
580 kobject_uevent(&part_to_dev(part
)->kobj
, KOBJ_ADD
);
581 disk_part_iter_exit(&piter
);
585 * device_add_disk - add partitioning information to kernel list
586 * @parent: parent device for the disk
587 * @disk: per-device partitioning information
589 * This function registers the partitioning information in @disk
592 * FIXME: error handling
594 void device_add_disk(struct device
*parent
, struct gendisk
*disk
)
596 struct backing_dev_info
*bdi
;
600 /* minors == 0 indicates to use ext devt from part0 and should
601 * be accompanied with EXT_DEVT flag. Make sure all
602 * parameters make sense.
604 WARN_ON(disk
->minors
&& !(disk
->major
|| disk
->first_minor
));
605 WARN_ON(!disk
->minors
&& !(disk
->flags
& GENHD_FL_EXT_DEVT
));
607 disk
->flags
|= GENHD_FL_UP
;
609 retval
= blk_alloc_devt(&disk
->part0
, &devt
);
614 disk_to_dev(disk
)->devt
= devt
;
616 /* ->major and ->first_minor aren't supposed to be
617 * dereferenced from here on, but set them just in case.
619 disk
->major
= MAJOR(devt
);
620 disk
->first_minor
= MINOR(devt
);
622 disk_alloc_events(disk
);
624 /* Register BDI before referencing it from bdev */
625 bdi
= disk
->queue
->backing_dev_info
;
626 bdi_register_owner(bdi
, disk_to_dev(disk
));
628 blk_register_region(disk_devt(disk
), disk
->minors
, NULL
,
629 exact_match
, exact_lock
, disk
);
630 register_disk(parent
, disk
);
631 blk_register_queue(disk
);
634 * Take an extra ref on queue which will be put on disk_release()
635 * so that it sticks around as long as @disk is there.
637 WARN_ON_ONCE(!blk_get_queue(disk
->queue
));
639 retval
= sysfs_create_link(&disk_to_dev(disk
)->kobj
, &bdi
->dev
->kobj
,
643 disk_add_events(disk
);
644 blk_integrity_add(disk
);
646 EXPORT_SYMBOL(device_add_disk
);
648 void del_gendisk(struct gendisk
*disk
)
650 struct disk_part_iter piter
;
651 struct hd_struct
*part
;
653 blk_integrity_del(disk
);
654 disk_del_events(disk
);
656 /* invalidate stuff */
657 disk_part_iter_init(&piter
, disk
,
658 DISK_PITER_INCL_EMPTY
| DISK_PITER_REVERSE
);
659 while ((part
= disk_part_iter_next(&piter
))) {
660 invalidate_partition(disk
, part
->partno
);
661 bdev_unhash_inode(part_devt(part
));
662 delete_partition(disk
, part
->partno
);
664 disk_part_iter_exit(&piter
);
666 invalidate_partition(disk
, 0);
667 bdev_unhash_inode(disk_devt(disk
));
668 set_capacity(disk
, 0);
669 disk
->flags
&= ~GENHD_FL_UP
;
671 sysfs_remove_link(&disk_to_dev(disk
)->kobj
, "bdi");
674 * Unregister bdi before releasing device numbers (as they can
675 * get reused and we'd get clashes in sysfs).
677 bdi_unregister(disk
->queue
->backing_dev_info
);
678 blk_unregister_queue(disk
);
682 blk_unregister_region(disk_devt(disk
), disk
->minors
);
684 part_stat_set_all(&disk
->part0
, 0);
685 disk
->part0
.stamp
= 0;
687 kobject_put(disk
->part0
.holder_dir
);
688 kobject_put(disk
->slave_dir
);
689 if (!sysfs_deprecated
)
690 sysfs_remove_link(block_depr
, dev_name(disk_to_dev(disk
)));
691 pm_runtime_set_memalloc_noio(disk_to_dev(disk
), false);
692 device_del(disk_to_dev(disk
));
694 EXPORT_SYMBOL(del_gendisk
);
696 /* sysfs access to bad-blocks list. */
697 static ssize_t
disk_badblocks_show(struct device
*dev
,
698 struct device_attribute
*attr
,
701 struct gendisk
*disk
= dev_to_disk(dev
);
704 return sprintf(page
, "\n");
706 return badblocks_show(disk
->bb
, page
, 0);
709 static ssize_t
disk_badblocks_store(struct device
*dev
,
710 struct device_attribute
*attr
,
711 const char *page
, size_t len
)
713 struct gendisk
*disk
= dev_to_disk(dev
);
718 return badblocks_store(disk
->bb
, page
, len
, 0);
722 * get_gendisk - get partitioning information for a given device
723 * @devt: device to get partitioning information for
724 * @partno: returned partition index
726 * This function gets the structure containing partitioning
727 * information for the given device @devt.
729 struct gendisk
*get_gendisk(dev_t devt
, int *partno
)
731 struct gendisk
*disk
= NULL
;
733 if (MAJOR(devt
) != BLOCK_EXT_MAJOR
) {
734 struct kobject
*kobj
;
736 kobj
= kobj_lookup(bdev_map
, devt
, partno
);
738 disk
= dev_to_disk(kobj_to_dev(kobj
));
740 struct hd_struct
*part
;
742 spin_lock_bh(&ext_devt_lock
);
743 part
= idr_find(&ext_devt_idr
, blk_mangle_minor(MINOR(devt
)));
744 if (part
&& get_disk(part_to_disk(part
))) {
745 *partno
= part
->partno
;
746 disk
= part_to_disk(part
);
748 spin_unlock_bh(&ext_devt_lock
);
753 EXPORT_SYMBOL(get_gendisk
);
756 * bdget_disk - do bdget() by gendisk and partition number
757 * @disk: gendisk of interest
758 * @partno: partition number
760 * Find partition @partno from @disk, do bdget() on it.
766 * Resulting block_device on success, NULL on failure.
768 struct block_device
*bdget_disk(struct gendisk
*disk
, int partno
)
770 struct hd_struct
*part
;
771 struct block_device
*bdev
= NULL
;
773 part
= disk_get_part(disk
, partno
);
775 bdev
= bdget(part_devt(part
));
780 EXPORT_SYMBOL(bdget_disk
);
783 * print a full list of all partitions - intended for places where the root
784 * filesystem can't be mounted and thus to give the victim some idea of what
787 void __init
printk_all_partitions(void)
789 struct class_dev_iter iter
;
792 class_dev_iter_init(&iter
, &block_class
, NULL
, &disk_type
);
793 while ((dev
= class_dev_iter_next(&iter
))) {
794 struct gendisk
*disk
= dev_to_disk(dev
);
795 struct disk_part_iter piter
;
796 struct hd_struct
*part
;
797 char name_buf
[BDEVNAME_SIZE
];
798 char devt_buf
[BDEVT_SIZE
];
801 * Don't show empty devices or things that have been
804 if (get_capacity(disk
) == 0 ||
805 (disk
->flags
& GENHD_FL_SUPPRESS_PARTITION_INFO
))
809 * Note, unlike /proc/partitions, I am showing the
810 * numbers in hex - the same format as the root=
813 disk_part_iter_init(&piter
, disk
, DISK_PITER_INCL_PART0
);
814 while ((part
= disk_part_iter_next(&piter
))) {
815 bool is_part0
= part
== &disk
->part0
;
817 printk("%s%s %10llu %s %s", is_part0
? "" : " ",
818 bdevt_str(part_devt(part
), devt_buf
),
819 (unsigned long long)part_nr_sects_read(part
) >> 1
820 , disk_name(disk
, part
->partno
, name_buf
),
821 part
->info
? part
->info
->uuid
: "");
823 if (dev
->parent
&& dev
->parent
->driver
)
824 printk(" driver: %s\n",
825 dev
->parent
->driver
->name
);
827 printk(" (driver?)\n");
831 disk_part_iter_exit(&piter
);
833 class_dev_iter_exit(&iter
);
836 #ifdef CONFIG_PROC_FS
838 static void *disk_seqf_start(struct seq_file
*seqf
, loff_t
*pos
)
841 struct class_dev_iter
*iter
;
844 iter
= kmalloc(sizeof(*iter
), GFP_KERNEL
);
846 return ERR_PTR(-ENOMEM
);
848 seqf
->private = iter
;
849 class_dev_iter_init(iter
, &block_class
, NULL
, &disk_type
);
851 dev
= class_dev_iter_next(iter
);
856 return dev_to_disk(dev
);
859 static void *disk_seqf_next(struct seq_file
*seqf
, void *v
, loff_t
*pos
)
864 dev
= class_dev_iter_next(seqf
->private);
866 return dev_to_disk(dev
);
871 static void disk_seqf_stop(struct seq_file
*seqf
, void *v
)
873 struct class_dev_iter
*iter
= seqf
->private;
875 /* stop is called even after start failed :-( */
877 class_dev_iter_exit(iter
);
879 seqf
->private = NULL
;
883 static void *show_partition_start(struct seq_file
*seqf
, loff_t
*pos
)
887 p
= disk_seqf_start(seqf
, pos
);
888 if (!IS_ERR_OR_NULL(p
) && !*pos
)
889 seq_puts(seqf
, "major minor #blocks name\n\n");
893 static int show_partition(struct seq_file
*seqf
, void *v
)
895 struct gendisk
*sgp
= v
;
896 struct disk_part_iter piter
;
897 struct hd_struct
*part
;
898 char buf
[BDEVNAME_SIZE
];
900 /* Don't show non-partitionable removeable devices or empty devices */
901 if (!get_capacity(sgp
) || (!disk_max_parts(sgp
) &&
902 (sgp
->flags
& GENHD_FL_REMOVABLE
)))
904 if (sgp
->flags
& GENHD_FL_SUPPRESS_PARTITION_INFO
)
907 /* show the full disk and all non-0 size partitions of it */
908 disk_part_iter_init(&piter
, sgp
, DISK_PITER_INCL_PART0
);
909 while ((part
= disk_part_iter_next(&piter
)))
910 seq_printf(seqf
, "%4d %7d %10llu %s\n",
911 MAJOR(part_devt(part
)), MINOR(part_devt(part
)),
912 (unsigned long long)part_nr_sects_read(part
) >> 1,
913 disk_name(sgp
, part
->partno
, buf
));
914 disk_part_iter_exit(&piter
);
919 static const struct seq_operations partitions_op
= {
920 .start
= show_partition_start
,
921 .next
= disk_seqf_next
,
922 .stop
= disk_seqf_stop
,
923 .show
= show_partition
926 static int partitions_open(struct inode
*inode
, struct file
*file
)
928 return seq_open(file
, &partitions_op
);
931 static const struct file_operations proc_partitions_operations
= {
932 .open
= partitions_open
,
935 .release
= seq_release
,
940 static struct kobject
*base_probe(dev_t devt
, int *partno
, void *data
)
942 if (request_module("block-major-%d-%d", MAJOR(devt
), MINOR(devt
)) > 0)
943 /* Make old-style 2.4 aliases work */
944 request_module("block-major-%d", MAJOR(devt
));
948 static int __init
genhd_device_init(void)
952 block_class
.dev_kobj
= sysfs_dev_block_kobj
;
953 error
= class_register(&block_class
);
956 bdev_map
= kobj_map_init(base_probe
, &block_class_lock
);
959 register_blkdev(BLOCK_EXT_MAJOR
, "blkext");
961 /* create top-level block dir */
962 if (!sysfs_deprecated
)
963 block_depr
= kobject_create_and_add("block", NULL
);
967 subsys_initcall(genhd_device_init
);
969 static ssize_t
disk_range_show(struct device
*dev
,
970 struct device_attribute
*attr
, char *buf
)
972 struct gendisk
*disk
= dev_to_disk(dev
);
974 return sprintf(buf
, "%d\n", disk
->minors
);
977 static ssize_t
disk_ext_range_show(struct device
*dev
,
978 struct device_attribute
*attr
, char *buf
)
980 struct gendisk
*disk
= dev_to_disk(dev
);
982 return sprintf(buf
, "%d\n", disk_max_parts(disk
));
985 static ssize_t
disk_removable_show(struct device
*dev
,
986 struct device_attribute
*attr
, char *buf
)
988 struct gendisk
*disk
= dev_to_disk(dev
);
990 return sprintf(buf
, "%d\n",
991 (disk
->flags
& GENHD_FL_REMOVABLE
? 1 : 0));
994 static ssize_t
disk_ro_show(struct device
*dev
,
995 struct device_attribute
*attr
, char *buf
)
997 struct gendisk
*disk
= dev_to_disk(dev
);
999 return sprintf(buf
, "%d\n", get_disk_ro(disk
) ? 1 : 0);
1002 static ssize_t
disk_capability_show(struct device
*dev
,
1003 struct device_attribute
*attr
, char *buf
)
1005 struct gendisk
*disk
= dev_to_disk(dev
);
1007 return sprintf(buf
, "%x\n", disk
->flags
);
1010 static ssize_t
disk_alignment_offset_show(struct device
*dev
,
1011 struct device_attribute
*attr
,
1014 struct gendisk
*disk
= dev_to_disk(dev
);
1016 return sprintf(buf
, "%d\n", queue_alignment_offset(disk
->queue
));
1019 static ssize_t
disk_discard_alignment_show(struct device
*dev
,
1020 struct device_attribute
*attr
,
1023 struct gendisk
*disk
= dev_to_disk(dev
);
1025 return sprintf(buf
, "%d\n", queue_discard_alignment(disk
->queue
));
1028 static DEVICE_ATTR(range
, S_IRUGO
, disk_range_show
, NULL
);
1029 static DEVICE_ATTR(ext_range
, S_IRUGO
, disk_ext_range_show
, NULL
);
1030 static DEVICE_ATTR(removable
, S_IRUGO
, disk_removable_show
, NULL
);
1031 static DEVICE_ATTR(ro
, S_IRUGO
, disk_ro_show
, NULL
);
1032 static DEVICE_ATTR(size
, S_IRUGO
, part_size_show
, NULL
);
1033 static DEVICE_ATTR(alignment_offset
, S_IRUGO
, disk_alignment_offset_show
, NULL
);
1034 static DEVICE_ATTR(discard_alignment
, S_IRUGO
, disk_discard_alignment_show
,
1036 static DEVICE_ATTR(capability
, S_IRUGO
, disk_capability_show
, NULL
);
1037 static DEVICE_ATTR(stat
, S_IRUGO
, part_stat_show
, NULL
);
1038 static DEVICE_ATTR(inflight
, S_IRUGO
, part_inflight_show
, NULL
);
1039 static DEVICE_ATTR(badblocks
, S_IRUGO
| S_IWUSR
, disk_badblocks_show
,
1040 disk_badblocks_store
);
1041 #ifdef CONFIG_FAIL_MAKE_REQUEST
1042 static struct device_attribute dev_attr_fail
=
1043 __ATTR(make
-it
-fail
, S_IRUGO
|S_IWUSR
, part_fail_show
, part_fail_store
);
1045 #ifdef CONFIG_FAIL_IO_TIMEOUT
1046 static struct device_attribute dev_attr_fail_timeout
=
1047 __ATTR(io
-timeout
-fail
, S_IRUGO
|S_IWUSR
, part_timeout_show
,
1048 part_timeout_store
);
1051 static struct attribute
*disk_attrs
[] = {
1052 &dev_attr_range
.attr
,
1053 &dev_attr_ext_range
.attr
,
1054 &dev_attr_removable
.attr
,
1056 &dev_attr_size
.attr
,
1057 &dev_attr_alignment_offset
.attr
,
1058 &dev_attr_discard_alignment
.attr
,
1059 &dev_attr_capability
.attr
,
1060 &dev_attr_stat
.attr
,
1061 &dev_attr_inflight
.attr
,
1062 &dev_attr_badblocks
.attr
,
1063 #ifdef CONFIG_FAIL_MAKE_REQUEST
1064 &dev_attr_fail
.attr
,
1066 #ifdef CONFIG_FAIL_IO_TIMEOUT
1067 &dev_attr_fail_timeout
.attr
,
1072 static umode_t
disk_visible(struct kobject
*kobj
, struct attribute
*a
, int n
)
1074 struct device
*dev
= container_of(kobj
, typeof(*dev
), kobj
);
1075 struct gendisk
*disk
= dev_to_disk(dev
);
1077 if (a
== &dev_attr_badblocks
.attr
&& !disk
->bb
)
1082 static struct attribute_group disk_attr_group
= {
1083 .attrs
= disk_attrs
,
1084 .is_visible
= disk_visible
,
1087 static const struct attribute_group
*disk_attr_groups
[] = {
1093 * disk_replace_part_tbl - replace disk->part_tbl in RCU-safe way
1094 * @disk: disk to replace part_tbl for
1095 * @new_ptbl: new part_tbl to install
1097 * Replace disk->part_tbl with @new_ptbl in RCU-safe way. The
1098 * original ptbl is freed using RCU callback.
1101 * Matching bd_mutx locked.
1103 static void disk_replace_part_tbl(struct gendisk
*disk
,
1104 struct disk_part_tbl
*new_ptbl
)
1106 struct disk_part_tbl
*old_ptbl
= disk
->part_tbl
;
1108 rcu_assign_pointer(disk
->part_tbl
, new_ptbl
);
1111 rcu_assign_pointer(old_ptbl
->last_lookup
, NULL
);
1112 kfree_rcu(old_ptbl
, rcu_head
);
1117 * disk_expand_part_tbl - expand disk->part_tbl
1118 * @disk: disk to expand part_tbl for
1119 * @partno: expand such that this partno can fit in
1121 * Expand disk->part_tbl such that @partno can fit in. disk->part_tbl
1122 * uses RCU to allow unlocked dereferencing for stats and other stuff.
1125 * Matching bd_mutex locked, might sleep.
1128 * 0 on success, -errno on failure.
1130 int disk_expand_part_tbl(struct gendisk
*disk
, int partno
)
1132 struct disk_part_tbl
*old_ptbl
= disk
->part_tbl
;
1133 struct disk_part_tbl
*new_ptbl
;
1134 int len
= old_ptbl
? old_ptbl
->len
: 0;
1139 * check for int overflow, since we can get here from blkpg_ioctl()
1140 * with a user passed 'partno'.
1142 target
= partno
+ 1;
1146 /* disk_max_parts() is zero during initialization, ignore if so */
1147 if (disk_max_parts(disk
) && target
> disk_max_parts(disk
))
1153 size
= sizeof(*new_ptbl
) + target
* sizeof(new_ptbl
->part
[0]);
1154 new_ptbl
= kzalloc_node(size
, GFP_KERNEL
, disk
->node_id
);
1158 new_ptbl
->len
= target
;
1160 for (i
= 0; i
< len
; i
++)
1161 rcu_assign_pointer(new_ptbl
->part
[i
], old_ptbl
->part
[i
]);
1163 disk_replace_part_tbl(disk
, new_ptbl
);
1167 static void disk_release(struct device
*dev
)
1169 struct gendisk
*disk
= dev_to_disk(dev
);
1171 blk_free_devt(dev
->devt
);
1172 disk_release_events(disk
);
1173 kfree(disk
->random
);
1174 disk_replace_part_tbl(disk
, NULL
);
1175 hd_free_part(&disk
->part0
);
1177 blk_put_queue(disk
->queue
);
1180 struct class block_class
= {
1184 static char *block_devnode(struct device
*dev
, umode_t
*mode
,
1185 kuid_t
*uid
, kgid_t
*gid
)
1187 struct gendisk
*disk
= dev_to_disk(dev
);
1190 return disk
->devnode(disk
, mode
);
1194 static const struct device_type disk_type
= {
1196 .groups
= disk_attr_groups
,
1197 .release
= disk_release
,
1198 .devnode
= block_devnode
,
1201 #ifdef CONFIG_PROC_FS
1203 * aggregate disk stat collector. Uses the same stats that the sysfs
1204 * entries do, above, but makes them available through one seq_file.
1206 * The output looks suspiciously like /proc/partitions with a bunch of
1209 static int diskstats_show(struct seq_file
*seqf
, void *v
)
1211 struct gendisk
*gp
= v
;
1212 struct disk_part_iter piter
;
1213 struct hd_struct
*hd
;
1214 char buf
[BDEVNAME_SIZE
];
1218 if (&disk_to_dev(gp)->kobj.entry == block_class.devices.next)
1219 seq_puts(seqf, "major minor name"
1220 " rio rmerge rsect ruse wio wmerge "
1221 "wsect wuse running use aveq"
1225 disk_part_iter_init(&piter
, gp
, DISK_PITER_INCL_EMPTY_PART0
);
1226 while ((hd
= disk_part_iter_next(&piter
))) {
1227 cpu
= part_stat_lock();
1228 part_round_stats(cpu
, hd
);
1230 seq_printf(seqf
, "%4d %7d %s %lu %lu %lu "
1231 "%u %lu %lu %lu %u %u %u %u\n",
1232 MAJOR(part_devt(hd
)), MINOR(part_devt(hd
)),
1233 disk_name(gp
, hd
->partno
, buf
),
1234 part_stat_read(hd
, ios
[READ
]),
1235 part_stat_read(hd
, merges
[READ
]),
1236 part_stat_read(hd
, sectors
[READ
]),
1237 jiffies_to_msecs(part_stat_read(hd
, ticks
[READ
])),
1238 part_stat_read(hd
, ios
[WRITE
]),
1239 part_stat_read(hd
, merges
[WRITE
]),
1240 part_stat_read(hd
, sectors
[WRITE
]),
1241 jiffies_to_msecs(part_stat_read(hd
, ticks
[WRITE
])),
1243 jiffies_to_msecs(part_stat_read(hd
, io_ticks
)),
1244 jiffies_to_msecs(part_stat_read(hd
, time_in_queue
))
1247 disk_part_iter_exit(&piter
);
1252 static const struct seq_operations diskstats_op
= {
1253 .start
= disk_seqf_start
,
1254 .next
= disk_seqf_next
,
1255 .stop
= disk_seqf_stop
,
1256 .show
= diskstats_show
1259 static int diskstats_open(struct inode
*inode
, struct file
*file
)
1261 return seq_open(file
, &diskstats_op
);
1264 static const struct file_operations proc_diskstats_operations
= {
1265 .open
= diskstats_open
,
1267 .llseek
= seq_lseek
,
1268 .release
= seq_release
,
1271 static int __init
proc_genhd_init(void)
1273 proc_create("diskstats", 0, NULL
, &proc_diskstats_operations
);
1274 proc_create("partitions", 0, NULL
, &proc_partitions_operations
);
1277 module_init(proc_genhd_init
);
1278 #endif /* CONFIG_PROC_FS */
1280 dev_t
blk_lookup_devt(const char *name
, int partno
)
1282 dev_t devt
= MKDEV(0, 0);
1283 struct class_dev_iter iter
;
1286 class_dev_iter_init(&iter
, &block_class
, NULL
, &disk_type
);
1287 while ((dev
= class_dev_iter_next(&iter
))) {
1288 struct gendisk
*disk
= dev_to_disk(dev
);
1289 struct hd_struct
*part
;
1291 if (strcmp(dev_name(dev
), name
))
1294 if (partno
< disk
->minors
) {
1295 /* We need to return the right devno, even
1296 * if the partition doesn't exist yet.
1298 devt
= MKDEV(MAJOR(dev
->devt
),
1299 MINOR(dev
->devt
) + partno
);
1302 part
= disk_get_part(disk
, partno
);
1304 devt
= part_devt(part
);
1305 disk_put_part(part
);
1308 disk_put_part(part
);
1310 class_dev_iter_exit(&iter
);
1313 EXPORT_SYMBOL(blk_lookup_devt
);
1315 struct gendisk
*alloc_disk(int minors
)
1317 return alloc_disk_node(minors
, NUMA_NO_NODE
);
1319 EXPORT_SYMBOL(alloc_disk
);
1321 struct gendisk
*alloc_disk_node(int minors
, int node_id
)
1323 struct gendisk
*disk
;
1325 disk
= kzalloc_node(sizeof(struct gendisk
), GFP_KERNEL
, node_id
);
1327 if (!init_part_stats(&disk
->part0
)) {
1331 disk
->node_id
= node_id
;
1332 if (disk_expand_part_tbl(disk
, 0)) {
1333 free_part_stats(&disk
->part0
);
1337 disk
->part_tbl
->part
[0] = &disk
->part0
;
1340 * set_capacity() and get_capacity() currently don't use
1341 * seqcounter to read/update the part0->nr_sects. Still init
1342 * the counter as we can read the sectors in IO submission
1343 * patch using seqence counters.
1345 * TODO: Ideally set_capacity() and get_capacity() should be
1346 * converted to make use of bd_mutex and sequence counters.
1348 seqcount_init(&disk
->part0
.nr_sects_seq
);
1349 if (hd_ref_init(&disk
->part0
)) {
1350 hd_free_part(&disk
->part0
);
1355 disk
->minors
= minors
;
1356 rand_initialize_disk(disk
);
1357 disk_to_dev(disk
)->class = &block_class
;
1358 disk_to_dev(disk
)->type
= &disk_type
;
1359 device_initialize(disk_to_dev(disk
));
1363 EXPORT_SYMBOL(alloc_disk_node
);
1365 struct kobject
*get_disk(struct gendisk
*disk
)
1367 struct module
*owner
;
1368 struct kobject
*kobj
;
1372 owner
= disk
->fops
->owner
;
1373 if (owner
&& !try_module_get(owner
))
1375 kobj
= kobject_get_unless_zero(&disk_to_dev(disk
)->kobj
);
1384 EXPORT_SYMBOL(get_disk
);
1386 void put_disk(struct gendisk
*disk
)
1389 kobject_put(&disk_to_dev(disk
)->kobj
);
1392 EXPORT_SYMBOL(put_disk
);
1394 static void set_disk_ro_uevent(struct gendisk
*gd
, int ro
)
1396 char event
[] = "DISK_RO=1";
1397 char *envp
[] = { event
, NULL
};
1401 kobject_uevent_env(&disk_to_dev(gd
)->kobj
, KOBJ_CHANGE
, envp
);
1404 void set_device_ro(struct block_device
*bdev
, int flag
)
1406 bdev
->bd_part
->policy
= flag
;
1409 EXPORT_SYMBOL(set_device_ro
);
1411 void set_disk_ro(struct gendisk
*disk
, int flag
)
1413 struct disk_part_iter piter
;
1414 struct hd_struct
*part
;
1416 if (disk
->part0
.policy
!= flag
) {
1417 set_disk_ro_uevent(disk
, flag
);
1418 disk
->part0
.policy
= flag
;
1421 disk_part_iter_init(&piter
, disk
, DISK_PITER_INCL_EMPTY
);
1422 while ((part
= disk_part_iter_next(&piter
)))
1423 part
->policy
= flag
;
1424 disk_part_iter_exit(&piter
);
1427 EXPORT_SYMBOL(set_disk_ro
);
1429 int bdev_read_only(struct block_device
*bdev
)
1433 return bdev
->bd_part
->policy
;
1436 EXPORT_SYMBOL(bdev_read_only
);
1438 int invalidate_partition(struct gendisk
*disk
, int partno
)
1441 struct block_device
*bdev
= bdget_disk(disk
, partno
);
1444 res
= __invalidate_device(bdev
, true);
1450 EXPORT_SYMBOL(invalidate_partition
);
1453 * Disk events - monitor disk events like media change and eject request.
1455 struct disk_events
{
1456 struct list_head node
; /* all disk_event's */
1457 struct gendisk
*disk
; /* the associated disk */
1460 struct mutex block_mutex
; /* protects blocking */
1461 int block
; /* event blocking depth */
1462 unsigned int pending
; /* events already sent out */
1463 unsigned int clearing
; /* events being cleared */
1465 long poll_msecs
; /* interval, -1 for default */
1466 struct delayed_work dwork
;
1469 static const char *disk_events_strs
[] = {
1470 [ilog2(DISK_EVENT_MEDIA_CHANGE
)] = "media_change",
1471 [ilog2(DISK_EVENT_EJECT_REQUEST
)] = "eject_request",
1474 static char *disk_uevents
[] = {
1475 [ilog2(DISK_EVENT_MEDIA_CHANGE
)] = "DISK_MEDIA_CHANGE=1",
1476 [ilog2(DISK_EVENT_EJECT_REQUEST
)] = "DISK_EJECT_REQUEST=1",
1479 /* list of all disk_events */
1480 static DEFINE_MUTEX(disk_events_mutex
);
1481 static LIST_HEAD(disk_events
);
1483 /* disable in-kernel polling by default */
1484 static unsigned long disk_events_dfl_poll_msecs
;
1486 static unsigned long disk_events_poll_jiffies(struct gendisk
*disk
)
1488 struct disk_events
*ev
= disk
->ev
;
1489 long intv_msecs
= 0;
1492 * If device-specific poll interval is set, always use it. If
1493 * the default is being used, poll iff there are events which
1494 * can't be monitored asynchronously.
1496 if (ev
->poll_msecs
>= 0)
1497 intv_msecs
= ev
->poll_msecs
;
1498 else if (disk
->events
& ~disk
->async_events
)
1499 intv_msecs
= disk_events_dfl_poll_msecs
;
1501 return msecs_to_jiffies(intv_msecs
);
1505 * disk_block_events - block and flush disk event checking
1506 * @disk: disk to block events for
1508 * On return from this function, it is guaranteed that event checking
1509 * isn't in progress and won't happen until unblocked by
1510 * disk_unblock_events(). Events blocking is counted and the actual
1511 * unblocking happens after the matching number of unblocks are done.
1513 * Note that this intentionally does not block event checking from
1514 * disk_clear_events().
1519 void disk_block_events(struct gendisk
*disk
)
1521 struct disk_events
*ev
= disk
->ev
;
1522 unsigned long flags
;
1529 * Outer mutex ensures that the first blocker completes canceling
1530 * the event work before further blockers are allowed to finish.
1532 mutex_lock(&ev
->block_mutex
);
1534 spin_lock_irqsave(&ev
->lock
, flags
);
1535 cancel
= !ev
->block
++;
1536 spin_unlock_irqrestore(&ev
->lock
, flags
);
1539 cancel_delayed_work_sync(&disk
->ev
->dwork
);
1541 mutex_unlock(&ev
->block_mutex
);
1544 static void __disk_unblock_events(struct gendisk
*disk
, bool check_now
)
1546 struct disk_events
*ev
= disk
->ev
;
1548 unsigned long flags
;
1550 spin_lock_irqsave(&ev
->lock
, flags
);
1552 if (WARN_ON_ONCE(ev
->block
<= 0))
1558 intv
= disk_events_poll_jiffies(disk
);
1560 queue_delayed_work(system_freezable_power_efficient_wq
,
1563 queue_delayed_work(system_freezable_power_efficient_wq
,
1566 spin_unlock_irqrestore(&ev
->lock
, flags
);
1570 * disk_unblock_events - unblock disk event checking
1571 * @disk: disk to unblock events for
1573 * Undo disk_block_events(). When the block count reaches zero, it
1574 * starts events polling if configured.
1577 * Don't care. Safe to call from irq context.
1579 void disk_unblock_events(struct gendisk
*disk
)
1582 __disk_unblock_events(disk
, false);
1586 * disk_flush_events - schedule immediate event checking and flushing
1587 * @disk: disk to check and flush events for
1588 * @mask: events to flush
1590 * Schedule immediate event checking on @disk if not blocked. Events in
1591 * @mask are scheduled to be cleared from the driver. Note that this
1592 * doesn't clear the events from @disk->ev.
1595 * If @mask is non-zero must be called with bdev->bd_mutex held.
1597 void disk_flush_events(struct gendisk
*disk
, unsigned int mask
)
1599 struct disk_events
*ev
= disk
->ev
;
1604 spin_lock_irq(&ev
->lock
);
1605 ev
->clearing
|= mask
;
1607 mod_delayed_work(system_freezable_power_efficient_wq
,
1609 spin_unlock_irq(&ev
->lock
);
1613 * disk_clear_events - synchronously check, clear and return pending events
1614 * @disk: disk to fetch and clear events from
1615 * @mask: mask of events to be fetched and cleared
1617 * Disk events are synchronously checked and pending events in @mask
1618 * are cleared and returned. This ignores the block count.
1623 unsigned int disk_clear_events(struct gendisk
*disk
, unsigned int mask
)
1625 const struct block_device_operations
*bdops
= disk
->fops
;
1626 struct disk_events
*ev
= disk
->ev
;
1627 unsigned int pending
;
1628 unsigned int clearing
= mask
;
1631 /* for drivers still using the old ->media_changed method */
1632 if ((mask
& DISK_EVENT_MEDIA_CHANGE
) &&
1633 bdops
->media_changed
&& bdops
->media_changed(disk
))
1634 return DISK_EVENT_MEDIA_CHANGE
;
1638 disk_block_events(disk
);
1641 * store the union of mask and ev->clearing on the stack so that the
1642 * race with disk_flush_events does not cause ambiguity (ev->clearing
1643 * can still be modified even if events are blocked).
1645 spin_lock_irq(&ev
->lock
);
1646 clearing
|= ev
->clearing
;
1648 spin_unlock_irq(&ev
->lock
);
1650 disk_check_events(ev
, &clearing
);
1652 * if ev->clearing is not 0, the disk_flush_events got called in the
1653 * middle of this function, so we want to run the workfn without delay.
1655 __disk_unblock_events(disk
, ev
->clearing
? true : false);
1657 /* then, fetch and clear pending events */
1658 spin_lock_irq(&ev
->lock
);
1659 pending
= ev
->pending
& mask
;
1660 ev
->pending
&= ~mask
;
1661 spin_unlock_irq(&ev
->lock
);
1662 WARN_ON_ONCE(clearing
& mask
);
1668 * Separate this part out so that a different pointer for clearing_ptr can be
1669 * passed in for disk_clear_events.
1671 static void disk_events_workfn(struct work_struct
*work
)
1673 struct delayed_work
*dwork
= to_delayed_work(work
);
1674 struct disk_events
*ev
= container_of(dwork
, struct disk_events
, dwork
);
1676 disk_check_events(ev
, &ev
->clearing
);
1679 static void disk_check_events(struct disk_events
*ev
,
1680 unsigned int *clearing_ptr
)
1682 struct gendisk
*disk
= ev
->disk
;
1683 char *envp
[ARRAY_SIZE(disk_uevents
) + 1] = { };
1684 unsigned int clearing
= *clearing_ptr
;
1685 unsigned int events
;
1687 int nr_events
= 0, i
;
1690 events
= disk
->fops
->check_events(disk
, clearing
);
1692 /* accumulate pending events and schedule next poll if necessary */
1693 spin_lock_irq(&ev
->lock
);
1695 events
&= ~ev
->pending
;
1696 ev
->pending
|= events
;
1697 *clearing_ptr
&= ~clearing
;
1699 intv
= disk_events_poll_jiffies(disk
);
1700 if (!ev
->block
&& intv
)
1701 queue_delayed_work(system_freezable_power_efficient_wq
,
1704 spin_unlock_irq(&ev
->lock
);
1707 * Tell userland about new events. Only the events listed in
1708 * @disk->events are reported. Unlisted events are processed the
1709 * same internally but never get reported to userland.
1711 for (i
= 0; i
< ARRAY_SIZE(disk_uevents
); i
++)
1712 if (events
& disk
->events
& (1 << i
))
1713 envp
[nr_events
++] = disk_uevents
[i
];
1716 kobject_uevent_env(&disk_to_dev(disk
)->kobj
, KOBJ_CHANGE
, envp
);
1720 * A disk events enabled device has the following sysfs nodes under
1721 * its /sys/block/X/ directory.
1723 * events : list of all supported events
1724 * events_async : list of events which can be detected w/o polling
1725 * events_poll_msecs : polling interval, 0: disable, -1: system default
1727 static ssize_t
__disk_events_show(unsigned int events
, char *buf
)
1729 const char *delim
= "";
1733 for (i
= 0; i
< ARRAY_SIZE(disk_events_strs
); i
++)
1734 if (events
& (1 << i
)) {
1735 pos
+= sprintf(buf
+ pos
, "%s%s",
1736 delim
, disk_events_strs
[i
]);
1740 pos
+= sprintf(buf
+ pos
, "\n");
1744 static ssize_t
disk_events_show(struct device
*dev
,
1745 struct device_attribute
*attr
, char *buf
)
1747 struct gendisk
*disk
= dev_to_disk(dev
);
1749 return __disk_events_show(disk
->events
, buf
);
1752 static ssize_t
disk_events_async_show(struct device
*dev
,
1753 struct device_attribute
*attr
, char *buf
)
1755 struct gendisk
*disk
= dev_to_disk(dev
);
1757 return __disk_events_show(disk
->async_events
, buf
);
1760 static ssize_t
disk_events_poll_msecs_show(struct device
*dev
,
1761 struct device_attribute
*attr
,
1764 struct gendisk
*disk
= dev_to_disk(dev
);
1766 return sprintf(buf
, "%ld\n", disk
->ev
->poll_msecs
);
1769 static ssize_t
disk_events_poll_msecs_store(struct device
*dev
,
1770 struct device_attribute
*attr
,
1771 const char *buf
, size_t count
)
1773 struct gendisk
*disk
= dev_to_disk(dev
);
1776 if (!count
|| !sscanf(buf
, "%ld", &intv
))
1779 if (intv
< 0 && intv
!= -1)
1782 disk_block_events(disk
);
1783 disk
->ev
->poll_msecs
= intv
;
1784 __disk_unblock_events(disk
, true);
1789 static const DEVICE_ATTR(events
, S_IRUGO
, disk_events_show
, NULL
);
1790 static const DEVICE_ATTR(events_async
, S_IRUGO
, disk_events_async_show
, NULL
);
1791 static const DEVICE_ATTR(events_poll_msecs
, S_IRUGO
|S_IWUSR
,
1792 disk_events_poll_msecs_show
,
1793 disk_events_poll_msecs_store
);
1795 static const struct attribute
*disk_events_attrs
[] = {
1796 &dev_attr_events
.attr
,
1797 &dev_attr_events_async
.attr
,
1798 &dev_attr_events_poll_msecs
.attr
,
1803 * The default polling interval can be specified by the kernel
1804 * parameter block.events_dfl_poll_msecs which defaults to 0
1805 * (disable). This can also be modified runtime by writing to
1806 * /sys/module/block/events_dfl_poll_msecs.
1808 static int disk_events_set_dfl_poll_msecs(const char *val
,
1809 const struct kernel_param
*kp
)
1811 struct disk_events
*ev
;
1814 ret
= param_set_ulong(val
, kp
);
1818 mutex_lock(&disk_events_mutex
);
1820 list_for_each_entry(ev
, &disk_events
, node
)
1821 disk_flush_events(ev
->disk
, 0);
1823 mutex_unlock(&disk_events_mutex
);
1828 static const struct kernel_param_ops disk_events_dfl_poll_msecs_param_ops
= {
1829 .set
= disk_events_set_dfl_poll_msecs
,
1830 .get
= param_get_ulong
,
1833 #undef MODULE_PARAM_PREFIX
1834 #define MODULE_PARAM_PREFIX "block."
1836 module_param_cb(events_dfl_poll_msecs
, &disk_events_dfl_poll_msecs_param_ops
,
1837 &disk_events_dfl_poll_msecs
, 0644);
1840 * disk_{alloc|add|del|release}_events - initialize and destroy disk_events.
1842 static void disk_alloc_events(struct gendisk
*disk
)
1844 struct disk_events
*ev
;
1846 if (!disk
->fops
->check_events
)
1849 ev
= kzalloc(sizeof(*ev
), GFP_KERNEL
);
1851 pr_warn("%s: failed to initialize events\n", disk
->disk_name
);
1855 INIT_LIST_HEAD(&ev
->node
);
1857 spin_lock_init(&ev
->lock
);
1858 mutex_init(&ev
->block_mutex
);
1860 ev
->poll_msecs
= -1;
1861 INIT_DELAYED_WORK(&ev
->dwork
, disk_events_workfn
);
1866 static void disk_add_events(struct gendisk
*disk
)
1871 /* FIXME: error handling */
1872 if (sysfs_create_files(&disk_to_dev(disk
)->kobj
, disk_events_attrs
) < 0)
1873 pr_warn("%s: failed to create sysfs files for events\n",
1876 mutex_lock(&disk_events_mutex
);
1877 list_add_tail(&disk
->ev
->node
, &disk_events
);
1878 mutex_unlock(&disk_events_mutex
);
1881 * Block count is initialized to 1 and the following initial
1882 * unblock kicks it into action.
1884 __disk_unblock_events(disk
, true);
1887 static void disk_del_events(struct gendisk
*disk
)
1892 disk_block_events(disk
);
1894 mutex_lock(&disk_events_mutex
);
1895 list_del_init(&disk
->ev
->node
);
1896 mutex_unlock(&disk_events_mutex
);
1898 sysfs_remove_files(&disk_to_dev(disk
)->kobj
, disk_events_attrs
);
1901 static void disk_release_events(struct gendisk
*disk
)
1903 /* the block count should be 1 from disk_del_events() */
1904 WARN_ON_ONCE(disk
->ev
&& disk
->ev
->block
!= 1);