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
);
48 void part_inc_in_flight(struct request_queue
*q
, struct hd_struct
*part
, int rw
)
53 part_stat_local_inc(part
, in_flight
[rw
]);
55 part_stat_local_inc(&part_to_disk(part
)->part0
, in_flight
[rw
]);
58 void part_dec_in_flight(struct request_queue
*q
, struct hd_struct
*part
, int rw
)
63 part_stat_local_dec(part
, in_flight
[rw
]);
65 part_stat_local_dec(&part_to_disk(part
)->part0
, in_flight
[rw
]);
68 unsigned int part_in_flight(struct request_queue
*q
, struct hd_struct
*part
)
71 unsigned int inflight
;
74 return blk_mq_in_flight(q
, part
);
78 for_each_possible_cpu(cpu
) {
79 inflight
+= part_stat_local_read_cpu(part
, in_flight
[0], cpu
) +
80 part_stat_local_read_cpu(part
, in_flight
[1], cpu
);
82 if ((int)inflight
< 0)
88 void part_in_flight_rw(struct request_queue
*q
, struct hd_struct
*part
,
89 unsigned int inflight
[2])
94 blk_mq_in_flight_rw(q
, part
, inflight
);
100 for_each_possible_cpu(cpu
) {
101 inflight
[0] += part_stat_local_read_cpu(part
, in_flight
[0], cpu
);
102 inflight
[1] += part_stat_local_read_cpu(part
, in_flight
[1], cpu
);
104 if ((int)inflight
[0] < 0)
106 if ((int)inflight
[1] < 0)
110 struct hd_struct
*__disk_get_part(struct gendisk
*disk
, int partno
)
112 struct disk_part_tbl
*ptbl
= rcu_dereference(disk
->part_tbl
);
114 if (unlikely(partno
< 0 || partno
>= ptbl
->len
))
116 return rcu_dereference(ptbl
->part
[partno
]);
120 * disk_get_part - get partition
121 * @disk: disk to look partition from
122 * @partno: partition number
124 * Look for partition @partno from @disk. If found, increment
125 * reference count and return it.
131 * Pointer to the found partition on success, NULL if not found.
133 struct hd_struct
*disk_get_part(struct gendisk
*disk
, int partno
)
135 struct hd_struct
*part
;
138 part
= __disk_get_part(disk
, partno
);
140 get_device(part_to_dev(part
));
145 EXPORT_SYMBOL_GPL(disk_get_part
);
148 * disk_part_iter_init - initialize partition iterator
149 * @piter: iterator to initialize
150 * @disk: disk to iterate over
151 * @flags: DISK_PITER_* flags
153 * Initialize @piter so that it iterates over partitions of @disk.
158 void disk_part_iter_init(struct disk_part_iter
*piter
, struct gendisk
*disk
,
161 struct disk_part_tbl
*ptbl
;
164 ptbl
= rcu_dereference(disk
->part_tbl
);
169 if (flags
& DISK_PITER_REVERSE
)
170 piter
->idx
= ptbl
->len
- 1;
171 else if (flags
& (DISK_PITER_INCL_PART0
| DISK_PITER_INCL_EMPTY_PART0
))
176 piter
->flags
= flags
;
180 EXPORT_SYMBOL_GPL(disk_part_iter_init
);
183 * disk_part_iter_next - proceed iterator to the next partition and return it
184 * @piter: iterator of interest
186 * Proceed @piter to the next partition and return it.
191 struct hd_struct
*disk_part_iter_next(struct disk_part_iter
*piter
)
193 struct disk_part_tbl
*ptbl
;
196 /* put the last partition */
197 disk_put_part(piter
->part
);
202 ptbl
= rcu_dereference(piter
->disk
->part_tbl
);
204 /* determine iteration parameters */
205 if (piter
->flags
& DISK_PITER_REVERSE
) {
207 if (piter
->flags
& (DISK_PITER_INCL_PART0
|
208 DISK_PITER_INCL_EMPTY_PART0
))
217 /* iterate to the next partition */
218 for (; piter
->idx
!= end
; piter
->idx
+= inc
) {
219 struct hd_struct
*part
;
221 part
= rcu_dereference(ptbl
->part
[piter
->idx
]);
224 if (!part_nr_sects_read(part
) &&
225 !(piter
->flags
& DISK_PITER_INCL_EMPTY
) &&
226 !(piter
->flags
& DISK_PITER_INCL_EMPTY_PART0
&&
230 get_device(part_to_dev(part
));
240 EXPORT_SYMBOL_GPL(disk_part_iter_next
);
243 * disk_part_iter_exit - finish up partition iteration
244 * @piter: iter of interest
246 * Called when iteration is over. Cleans up @piter.
251 void disk_part_iter_exit(struct disk_part_iter
*piter
)
253 disk_put_part(piter
->part
);
256 EXPORT_SYMBOL_GPL(disk_part_iter_exit
);
258 static inline int sector_in_part(struct hd_struct
*part
, sector_t sector
)
260 return part
->start_sect
<= sector
&&
261 sector
< part
->start_sect
+ part_nr_sects_read(part
);
265 * disk_map_sector_rcu - map sector to partition
266 * @disk: gendisk of interest
267 * @sector: sector to map
269 * Find out which partition @sector maps to on @disk. This is
270 * primarily used for stats accounting.
273 * RCU read locked. The returned partition pointer is valid only
274 * while preemption is disabled.
277 * Found partition on success, part0 is returned if no partition matches
279 struct hd_struct
*disk_map_sector_rcu(struct gendisk
*disk
, sector_t sector
)
281 struct disk_part_tbl
*ptbl
;
282 struct hd_struct
*part
;
285 ptbl
= rcu_dereference(disk
->part_tbl
);
287 part
= rcu_dereference(ptbl
->last_lookup
);
288 if (part
&& sector_in_part(part
, sector
))
291 for (i
= 1; i
< ptbl
->len
; i
++) {
292 part
= rcu_dereference(ptbl
->part
[i
]);
294 if (part
&& sector_in_part(part
, sector
)) {
295 rcu_assign_pointer(ptbl
->last_lookup
, part
);
301 EXPORT_SYMBOL_GPL(disk_map_sector_rcu
);
304 * Can be deleted altogether. Later.
307 #define BLKDEV_MAJOR_HASH_SIZE 255
308 static struct blk_major_name
{
309 struct blk_major_name
*next
;
312 } *major_names
[BLKDEV_MAJOR_HASH_SIZE
];
314 /* index in the above - for now: assume no multimajor ranges */
315 static inline int major_to_index(unsigned major
)
317 return major
% BLKDEV_MAJOR_HASH_SIZE
;
320 #ifdef CONFIG_PROC_FS
321 void blkdev_show(struct seq_file
*seqf
, off_t offset
)
323 struct blk_major_name
*dp
;
325 mutex_lock(&block_class_lock
);
326 for (dp
= major_names
[major_to_index(offset
)]; dp
; dp
= dp
->next
)
327 if (dp
->major
== offset
)
328 seq_printf(seqf
, "%3d %s\n", dp
->major
, dp
->name
);
329 mutex_unlock(&block_class_lock
);
331 #endif /* CONFIG_PROC_FS */
334 * register_blkdev - register a new block device
336 * @major: the requested major device number [1..BLKDEV_MAJOR_MAX-1]. If
337 * @major = 0, try to allocate any unused major number.
338 * @name: the name of the new block device as a zero terminated string
340 * The @name must be unique within the system.
342 * The return value depends on the @major input parameter:
344 * - if a major device number was requested in range [1..BLKDEV_MAJOR_MAX-1]
345 * then the function returns zero on success, or a negative error code
346 * - if any unused major number was requested with @major = 0 parameter
347 * then the return value is the allocated major number in range
348 * [1..BLKDEV_MAJOR_MAX-1] or a negative error code otherwise
350 * See Documentation/admin-guide/devices.txt for the list of allocated
353 int register_blkdev(unsigned int major
, const char *name
)
355 struct blk_major_name
**n
, *p
;
358 mutex_lock(&block_class_lock
);
362 for (index
= ARRAY_SIZE(major_names
)-1; index
> 0; index
--) {
363 if (major_names
[index
] == NULL
)
368 printk("register_blkdev: failed to get major for %s\n",
377 if (major
>= BLKDEV_MAJOR_MAX
) {
378 pr_err("register_blkdev: major requested (%u) is greater than the maximum (%u) for %s\n",
379 major
, BLKDEV_MAJOR_MAX
-1, name
);
385 p
= kmalloc(sizeof(struct blk_major_name
), GFP_KERNEL
);
392 strlcpy(p
->name
, name
, sizeof(p
->name
));
394 index
= major_to_index(major
);
396 for (n
= &major_names
[index
]; *n
; n
= &(*n
)->next
) {
397 if ((*n
)->major
== major
)
406 printk("register_blkdev: cannot get major %u for %s\n",
411 mutex_unlock(&block_class_lock
);
415 EXPORT_SYMBOL(register_blkdev
);
417 void unregister_blkdev(unsigned int major
, const char *name
)
419 struct blk_major_name
**n
;
420 struct blk_major_name
*p
= NULL
;
421 int index
= major_to_index(major
);
423 mutex_lock(&block_class_lock
);
424 for (n
= &major_names
[index
]; *n
; n
= &(*n
)->next
)
425 if ((*n
)->major
== major
)
427 if (!*n
|| strcmp((*n
)->name
, name
)) {
433 mutex_unlock(&block_class_lock
);
437 EXPORT_SYMBOL(unregister_blkdev
);
439 static struct kobj_map
*bdev_map
;
442 * blk_mangle_minor - scatter minor numbers apart
443 * @minor: minor number to mangle
445 * Scatter consecutively allocated @minor number apart if MANGLE_DEVT
446 * is enabled. Mangling twice gives the original value.
454 static int blk_mangle_minor(int minor
)
456 #ifdef CONFIG_DEBUG_BLOCK_EXT_DEVT
459 for (i
= 0; i
< MINORBITS
/ 2; i
++) {
460 int low
= minor
& (1 << i
);
461 int high
= minor
& (1 << (MINORBITS
- 1 - i
));
462 int distance
= MINORBITS
- 1 - 2 * i
;
464 minor
^= low
| high
; /* clear both bits */
465 low
<<= distance
; /* swap the positions */
467 minor
|= low
| high
; /* and set */
474 * blk_alloc_devt - allocate a dev_t for a partition
475 * @part: partition to allocate dev_t for
476 * @devt: out parameter for resulting dev_t
478 * Allocate a dev_t for block device.
481 * 0 on success, allocated dev_t is returned in *@devt. -errno on
487 int blk_alloc_devt(struct hd_struct
*part
, dev_t
*devt
)
489 struct gendisk
*disk
= part_to_disk(part
);
492 /* in consecutive minor range? */
493 if (part
->partno
< disk
->minors
) {
494 *devt
= MKDEV(disk
->major
, disk
->first_minor
+ part
->partno
);
498 /* allocate ext devt */
499 idr_preload(GFP_KERNEL
);
501 spin_lock_bh(&ext_devt_lock
);
502 idx
= idr_alloc(&ext_devt_idr
, part
, 0, NR_EXT_DEVT
, GFP_NOWAIT
);
503 spin_unlock_bh(&ext_devt_lock
);
507 return idx
== -ENOSPC
? -EBUSY
: idx
;
509 *devt
= MKDEV(BLOCK_EXT_MAJOR
, blk_mangle_minor(idx
));
514 * blk_free_devt - free a dev_t
515 * @devt: dev_t to free
517 * Free @devt which was allocated using blk_alloc_devt().
522 void blk_free_devt(dev_t devt
)
524 if (devt
== MKDEV(0, 0))
527 if (MAJOR(devt
) == BLOCK_EXT_MAJOR
) {
528 spin_lock_bh(&ext_devt_lock
);
529 idr_remove(&ext_devt_idr
, blk_mangle_minor(MINOR(devt
)));
530 spin_unlock_bh(&ext_devt_lock
);
534 static char *bdevt_str(dev_t devt
, char *buf
)
536 if (MAJOR(devt
) <= 0xff && MINOR(devt
) <= 0xff) {
537 char tbuf
[BDEVT_SIZE
];
538 snprintf(tbuf
, BDEVT_SIZE
, "%02x%02x", MAJOR(devt
), MINOR(devt
));
539 snprintf(buf
, BDEVT_SIZE
, "%-9s", tbuf
);
541 snprintf(buf
, BDEVT_SIZE
, "%03x:%05x", MAJOR(devt
), MINOR(devt
));
547 * Register device numbers dev..(dev+range-1)
548 * range must be nonzero
549 * The hash chain is sorted on range, so that subranges can override.
551 void blk_register_region(dev_t devt
, unsigned long range
, struct module
*module
,
552 struct kobject
*(*probe
)(dev_t
, int *, void *),
553 int (*lock
)(dev_t
, void *), void *data
)
555 kobj_map(bdev_map
, devt
, range
, module
, probe
, lock
, data
);
558 EXPORT_SYMBOL(blk_register_region
);
560 void blk_unregister_region(dev_t devt
, unsigned long range
)
562 kobj_unmap(bdev_map
, devt
, range
);
565 EXPORT_SYMBOL(blk_unregister_region
);
567 static struct kobject
*exact_match(dev_t devt
, int *partno
, void *data
)
569 struct gendisk
*p
= data
;
571 return &disk_to_dev(p
)->kobj
;
574 static int exact_lock(dev_t devt
, void *data
)
576 struct gendisk
*p
= data
;
578 if (!get_disk_and_module(p
))
583 static void register_disk(struct device
*parent
, struct gendisk
*disk
,
584 const struct attribute_group
**groups
)
586 struct device
*ddev
= disk_to_dev(disk
);
587 struct block_device
*bdev
;
588 struct disk_part_iter piter
;
589 struct hd_struct
*part
;
592 ddev
->parent
= parent
;
594 dev_set_name(ddev
, "%s", disk
->disk_name
);
596 /* delay uevents, until we scanned partition table */
597 dev_set_uevent_suppress(ddev
, 1);
600 WARN_ON(ddev
->groups
);
601 ddev
->groups
= groups
;
603 if (device_add(ddev
))
605 if (!sysfs_deprecated
) {
606 err
= sysfs_create_link(block_depr
, &ddev
->kobj
,
607 kobject_name(&ddev
->kobj
));
615 * avoid probable deadlock caused by allocating memory with
616 * GFP_KERNEL in runtime_resume callback of its all ancestor
619 pm_runtime_set_memalloc_noio(ddev
, true);
621 disk
->part0
.holder_dir
= kobject_create_and_add("holders", &ddev
->kobj
);
622 disk
->slave_dir
= kobject_create_and_add("slaves", &ddev
->kobj
);
624 if (disk
->flags
& GENHD_FL_HIDDEN
) {
625 dev_set_uevent_suppress(ddev
, 0);
629 /* No minors to use for partitions */
630 if (!disk_part_scan_enabled(disk
))
633 /* No such device (e.g., media were just removed) */
634 if (!get_capacity(disk
))
637 bdev
= bdget_disk(disk
, 0);
641 bdev
->bd_invalidated
= 1;
642 err
= blkdev_get(bdev
, FMODE_READ
, NULL
);
645 blkdev_put(bdev
, FMODE_READ
);
648 /* announce disk after possible partitions are created */
649 dev_set_uevent_suppress(ddev
, 0);
650 kobject_uevent(&ddev
->kobj
, KOBJ_ADD
);
652 /* announce possible partitions */
653 disk_part_iter_init(&piter
, disk
, 0);
654 while ((part
= disk_part_iter_next(&piter
)))
655 kobject_uevent(&part_to_dev(part
)->kobj
, KOBJ_ADD
);
656 disk_part_iter_exit(&piter
);
658 err
= sysfs_create_link(&ddev
->kobj
,
659 &disk
->queue
->backing_dev_info
->dev
->kobj
,
665 * __device_add_disk - add disk information to kernel list
666 * @parent: parent device for the disk
667 * @disk: per-device partitioning information
668 * @groups: Additional per-device sysfs groups
669 * @register_queue: register the queue if set to true
671 * This function registers the partitioning information in @disk
674 * FIXME: error handling
676 static void __device_add_disk(struct device
*parent
, struct gendisk
*disk
,
677 const struct attribute_group
**groups
,
683 /* minors == 0 indicates to use ext devt from part0 and should
684 * be accompanied with EXT_DEVT flag. Make sure all
685 * parameters make sense.
687 WARN_ON(disk
->minors
&& !(disk
->major
|| disk
->first_minor
));
688 WARN_ON(!disk
->minors
&&
689 !(disk
->flags
& (GENHD_FL_EXT_DEVT
| GENHD_FL_HIDDEN
)));
691 disk
->flags
|= GENHD_FL_UP
;
693 retval
= blk_alloc_devt(&disk
->part0
, &devt
);
698 disk
->major
= MAJOR(devt
);
699 disk
->first_minor
= MINOR(devt
);
701 disk_alloc_events(disk
);
703 if (disk
->flags
& GENHD_FL_HIDDEN
) {
705 * Don't let hidden disks show up in /proc/partitions,
706 * and don't bother scanning for partitions either.
708 disk
->flags
|= GENHD_FL_SUPPRESS_PARTITION_INFO
;
709 disk
->flags
|= GENHD_FL_NO_PART_SCAN
;
713 /* Register BDI before referencing it from bdev */
714 disk_to_dev(disk
)->devt
= devt
;
715 ret
= bdi_register_owner(disk
->queue
->backing_dev_info
,
718 blk_register_region(disk_devt(disk
), disk
->minors
, NULL
,
719 exact_match
, exact_lock
, disk
);
721 register_disk(parent
, disk
, groups
);
723 blk_register_queue(disk
);
726 * Take an extra ref on queue which will be put on disk_release()
727 * so that it sticks around as long as @disk is there.
729 WARN_ON_ONCE(!blk_get_queue(disk
->queue
));
731 disk_add_events(disk
);
732 blk_integrity_add(disk
);
735 void device_add_disk(struct device
*parent
, struct gendisk
*disk
,
736 const struct attribute_group
**groups
)
739 __device_add_disk(parent
, disk
, groups
, true);
741 EXPORT_SYMBOL(device_add_disk
);
743 void device_add_disk_no_queue_reg(struct device
*parent
, struct gendisk
*disk
)
745 __device_add_disk(parent
, disk
, NULL
, false);
747 EXPORT_SYMBOL(device_add_disk_no_queue_reg
);
749 void del_gendisk(struct gendisk
*disk
)
751 struct disk_part_iter piter
;
752 struct hd_struct
*part
;
754 blk_integrity_del(disk
);
755 disk_del_events(disk
);
758 * Block lookups of the disk until all bdevs are unhashed and the
759 * disk is marked as dead (GENHD_FL_UP cleared).
761 down_write(&disk
->lookup_sem
);
762 /* invalidate stuff */
763 disk_part_iter_init(&piter
, disk
,
764 DISK_PITER_INCL_EMPTY
| DISK_PITER_REVERSE
);
765 while ((part
= disk_part_iter_next(&piter
))) {
766 invalidate_partition(disk
, part
->partno
);
767 bdev_unhash_inode(part_devt(part
));
768 delete_partition(disk
, part
->partno
);
770 disk_part_iter_exit(&piter
);
772 invalidate_partition(disk
, 0);
773 bdev_unhash_inode(disk_devt(disk
));
774 set_capacity(disk
, 0);
775 disk
->flags
&= ~GENHD_FL_UP
;
776 up_write(&disk
->lookup_sem
);
778 if (!(disk
->flags
& GENHD_FL_HIDDEN
))
779 sysfs_remove_link(&disk_to_dev(disk
)->kobj
, "bdi");
782 * Unregister bdi before releasing device numbers (as they can
783 * get reused and we'd get clashes in sysfs).
785 if (!(disk
->flags
& GENHD_FL_HIDDEN
))
786 bdi_unregister(disk
->queue
->backing_dev_info
);
787 blk_unregister_queue(disk
);
792 if (!(disk
->flags
& GENHD_FL_HIDDEN
))
793 blk_unregister_region(disk_devt(disk
), disk
->minors
);
795 kobject_put(disk
->part0
.holder_dir
);
796 kobject_put(disk
->slave_dir
);
798 part_stat_set_all(&disk
->part0
, 0);
799 disk
->part0
.stamp
= 0;
800 if (!sysfs_deprecated
)
801 sysfs_remove_link(block_depr
, dev_name(disk_to_dev(disk
)));
802 pm_runtime_set_memalloc_noio(disk_to_dev(disk
), false);
803 device_del(disk_to_dev(disk
));
805 EXPORT_SYMBOL(del_gendisk
);
807 /* sysfs access to bad-blocks list. */
808 static ssize_t
disk_badblocks_show(struct device
*dev
,
809 struct device_attribute
*attr
,
812 struct gendisk
*disk
= dev_to_disk(dev
);
815 return sprintf(page
, "\n");
817 return badblocks_show(disk
->bb
, page
, 0);
820 static ssize_t
disk_badblocks_store(struct device
*dev
,
821 struct device_attribute
*attr
,
822 const char *page
, size_t len
)
824 struct gendisk
*disk
= dev_to_disk(dev
);
829 return badblocks_store(disk
->bb
, page
, len
, 0);
833 * get_gendisk - get partitioning information for a given device
834 * @devt: device to get partitioning information for
835 * @partno: returned partition index
837 * This function gets the structure containing partitioning
838 * information for the given device @devt.
840 struct gendisk
*get_gendisk(dev_t devt
, int *partno
)
842 struct gendisk
*disk
= NULL
;
844 if (MAJOR(devt
) != BLOCK_EXT_MAJOR
) {
845 struct kobject
*kobj
;
847 kobj
= kobj_lookup(bdev_map
, devt
, partno
);
849 disk
= dev_to_disk(kobj_to_dev(kobj
));
851 struct hd_struct
*part
;
853 spin_lock_bh(&ext_devt_lock
);
854 part
= idr_find(&ext_devt_idr
, blk_mangle_minor(MINOR(devt
)));
855 if (part
&& get_disk_and_module(part_to_disk(part
))) {
856 *partno
= part
->partno
;
857 disk
= part_to_disk(part
);
859 spin_unlock_bh(&ext_devt_lock
);
866 * Synchronize with del_gendisk() to not return disk that is being
869 down_read(&disk
->lookup_sem
);
870 if (unlikely((disk
->flags
& GENHD_FL_HIDDEN
) ||
871 !(disk
->flags
& GENHD_FL_UP
))) {
872 up_read(&disk
->lookup_sem
);
873 put_disk_and_module(disk
);
876 up_read(&disk
->lookup_sem
);
880 EXPORT_SYMBOL(get_gendisk
);
883 * bdget_disk - do bdget() by gendisk and partition number
884 * @disk: gendisk of interest
885 * @partno: partition number
887 * Find partition @partno from @disk, do bdget() on it.
893 * Resulting block_device on success, NULL on failure.
895 struct block_device
*bdget_disk(struct gendisk
*disk
, int partno
)
897 struct hd_struct
*part
;
898 struct block_device
*bdev
= NULL
;
900 part
= disk_get_part(disk
, partno
);
902 bdev
= bdget(part_devt(part
));
907 EXPORT_SYMBOL(bdget_disk
);
910 * print a full list of all partitions - intended for places where the root
911 * filesystem can't be mounted and thus to give the victim some idea of what
914 void __init
printk_all_partitions(void)
916 struct class_dev_iter iter
;
919 class_dev_iter_init(&iter
, &block_class
, NULL
, &disk_type
);
920 while ((dev
= class_dev_iter_next(&iter
))) {
921 struct gendisk
*disk
= dev_to_disk(dev
);
922 struct disk_part_iter piter
;
923 struct hd_struct
*part
;
924 char name_buf
[BDEVNAME_SIZE
];
925 char devt_buf
[BDEVT_SIZE
];
928 * Don't show empty devices or things that have been
931 if (get_capacity(disk
) == 0 ||
932 (disk
->flags
& GENHD_FL_SUPPRESS_PARTITION_INFO
))
936 * Note, unlike /proc/partitions, I am showing the
937 * numbers in hex - the same format as the root=
940 disk_part_iter_init(&piter
, disk
, DISK_PITER_INCL_PART0
);
941 while ((part
= disk_part_iter_next(&piter
))) {
942 bool is_part0
= part
== &disk
->part0
;
944 printk("%s%s %10llu %s %s", is_part0
? "" : " ",
945 bdevt_str(part_devt(part
), devt_buf
),
946 (unsigned long long)part_nr_sects_read(part
) >> 1
947 , disk_name(disk
, part
->partno
, name_buf
),
948 part
->info
? part
->info
->uuid
: "");
950 if (dev
->parent
&& dev
->parent
->driver
)
951 printk(" driver: %s\n",
952 dev
->parent
->driver
->name
);
954 printk(" (driver?)\n");
958 disk_part_iter_exit(&piter
);
960 class_dev_iter_exit(&iter
);
963 #ifdef CONFIG_PROC_FS
965 static void *disk_seqf_start(struct seq_file
*seqf
, loff_t
*pos
)
968 struct class_dev_iter
*iter
;
971 iter
= kmalloc(sizeof(*iter
), GFP_KERNEL
);
973 return ERR_PTR(-ENOMEM
);
975 seqf
->private = iter
;
976 class_dev_iter_init(iter
, &block_class
, NULL
, &disk_type
);
978 dev
= class_dev_iter_next(iter
);
983 return dev_to_disk(dev
);
986 static void *disk_seqf_next(struct seq_file
*seqf
, void *v
, loff_t
*pos
)
991 dev
= class_dev_iter_next(seqf
->private);
993 return dev_to_disk(dev
);
998 static void disk_seqf_stop(struct seq_file
*seqf
, void *v
)
1000 struct class_dev_iter
*iter
= seqf
->private;
1002 /* stop is called even after start failed :-( */
1004 class_dev_iter_exit(iter
);
1006 seqf
->private = NULL
;
1010 static void *show_partition_start(struct seq_file
*seqf
, loff_t
*pos
)
1014 p
= disk_seqf_start(seqf
, pos
);
1015 if (!IS_ERR_OR_NULL(p
) && !*pos
)
1016 seq_puts(seqf
, "major minor #blocks name\n\n");
1020 static int show_partition(struct seq_file
*seqf
, void *v
)
1022 struct gendisk
*sgp
= v
;
1023 struct disk_part_iter piter
;
1024 struct hd_struct
*part
;
1025 char buf
[BDEVNAME_SIZE
];
1027 /* Don't show non-partitionable removeable devices or empty devices */
1028 if (!get_capacity(sgp
) || (!disk_max_parts(sgp
) &&
1029 (sgp
->flags
& GENHD_FL_REMOVABLE
)))
1031 if (sgp
->flags
& GENHD_FL_SUPPRESS_PARTITION_INFO
)
1034 /* show the full disk and all non-0 size partitions of it */
1035 disk_part_iter_init(&piter
, sgp
, DISK_PITER_INCL_PART0
);
1036 while ((part
= disk_part_iter_next(&piter
)))
1037 seq_printf(seqf
, "%4d %7d %10llu %s\n",
1038 MAJOR(part_devt(part
)), MINOR(part_devt(part
)),
1039 (unsigned long long)part_nr_sects_read(part
) >> 1,
1040 disk_name(sgp
, part
->partno
, buf
));
1041 disk_part_iter_exit(&piter
);
1046 static const struct seq_operations partitions_op
= {
1047 .start
= show_partition_start
,
1048 .next
= disk_seqf_next
,
1049 .stop
= disk_seqf_stop
,
1050 .show
= show_partition
1055 static struct kobject
*base_probe(dev_t devt
, int *partno
, void *data
)
1057 if (request_module("block-major-%d-%d", MAJOR(devt
), MINOR(devt
)) > 0)
1058 /* Make old-style 2.4 aliases work */
1059 request_module("block-major-%d", MAJOR(devt
));
1063 static int __init
genhd_device_init(void)
1067 block_class
.dev_kobj
= sysfs_dev_block_kobj
;
1068 error
= class_register(&block_class
);
1069 if (unlikely(error
))
1071 bdev_map
= kobj_map_init(base_probe
, &block_class_lock
);
1074 register_blkdev(BLOCK_EXT_MAJOR
, "blkext");
1076 /* create top-level block dir */
1077 if (!sysfs_deprecated
)
1078 block_depr
= kobject_create_and_add("block", NULL
);
1082 subsys_initcall(genhd_device_init
);
1084 static ssize_t
disk_range_show(struct device
*dev
,
1085 struct device_attribute
*attr
, char *buf
)
1087 struct gendisk
*disk
= dev_to_disk(dev
);
1089 return sprintf(buf
, "%d\n", disk
->minors
);
1092 static ssize_t
disk_ext_range_show(struct device
*dev
,
1093 struct device_attribute
*attr
, char *buf
)
1095 struct gendisk
*disk
= dev_to_disk(dev
);
1097 return sprintf(buf
, "%d\n", disk_max_parts(disk
));
1100 static ssize_t
disk_removable_show(struct device
*dev
,
1101 struct device_attribute
*attr
, char *buf
)
1103 struct gendisk
*disk
= dev_to_disk(dev
);
1105 return sprintf(buf
, "%d\n",
1106 (disk
->flags
& GENHD_FL_REMOVABLE
? 1 : 0));
1109 static ssize_t
disk_hidden_show(struct device
*dev
,
1110 struct device_attribute
*attr
, char *buf
)
1112 struct gendisk
*disk
= dev_to_disk(dev
);
1114 return sprintf(buf
, "%d\n",
1115 (disk
->flags
& GENHD_FL_HIDDEN
? 1 : 0));
1118 static ssize_t
disk_ro_show(struct device
*dev
,
1119 struct device_attribute
*attr
, char *buf
)
1121 struct gendisk
*disk
= dev_to_disk(dev
);
1123 return sprintf(buf
, "%d\n", get_disk_ro(disk
) ? 1 : 0);
1126 static ssize_t
disk_capability_show(struct device
*dev
,
1127 struct device_attribute
*attr
, char *buf
)
1129 struct gendisk
*disk
= dev_to_disk(dev
);
1131 return sprintf(buf
, "%x\n", disk
->flags
);
1134 static ssize_t
disk_alignment_offset_show(struct device
*dev
,
1135 struct device_attribute
*attr
,
1138 struct gendisk
*disk
= dev_to_disk(dev
);
1140 return sprintf(buf
, "%d\n", queue_alignment_offset(disk
->queue
));
1143 static ssize_t
disk_discard_alignment_show(struct device
*dev
,
1144 struct device_attribute
*attr
,
1147 struct gendisk
*disk
= dev_to_disk(dev
);
1149 return sprintf(buf
, "%d\n", queue_discard_alignment(disk
->queue
));
1152 static DEVICE_ATTR(range
, 0444, disk_range_show
, NULL
);
1153 static DEVICE_ATTR(ext_range
, 0444, disk_ext_range_show
, NULL
);
1154 static DEVICE_ATTR(removable
, 0444, disk_removable_show
, NULL
);
1155 static DEVICE_ATTR(hidden
, 0444, disk_hidden_show
, NULL
);
1156 static DEVICE_ATTR(ro
, 0444, disk_ro_show
, NULL
);
1157 static DEVICE_ATTR(size
, 0444, part_size_show
, NULL
);
1158 static DEVICE_ATTR(alignment_offset
, 0444, disk_alignment_offset_show
, NULL
);
1159 static DEVICE_ATTR(discard_alignment
, 0444, disk_discard_alignment_show
, NULL
);
1160 static DEVICE_ATTR(capability
, 0444, disk_capability_show
, NULL
);
1161 static DEVICE_ATTR(stat
, 0444, part_stat_show
, NULL
);
1162 static DEVICE_ATTR(inflight
, 0444, part_inflight_show
, NULL
);
1163 static DEVICE_ATTR(badblocks
, 0644, disk_badblocks_show
, disk_badblocks_store
);
1164 #ifdef CONFIG_FAIL_MAKE_REQUEST
1165 static struct device_attribute dev_attr_fail
=
1166 __ATTR(make
-it
-fail
, 0644, part_fail_show
, part_fail_store
);
1168 #ifdef CONFIG_FAIL_IO_TIMEOUT
1169 static struct device_attribute dev_attr_fail_timeout
=
1170 __ATTR(io
-timeout
-fail
, 0644, part_timeout_show
, part_timeout_store
);
1173 static struct attribute
*disk_attrs
[] = {
1174 &dev_attr_range
.attr
,
1175 &dev_attr_ext_range
.attr
,
1176 &dev_attr_removable
.attr
,
1177 &dev_attr_hidden
.attr
,
1179 &dev_attr_size
.attr
,
1180 &dev_attr_alignment_offset
.attr
,
1181 &dev_attr_discard_alignment
.attr
,
1182 &dev_attr_capability
.attr
,
1183 &dev_attr_stat
.attr
,
1184 &dev_attr_inflight
.attr
,
1185 &dev_attr_badblocks
.attr
,
1186 #ifdef CONFIG_FAIL_MAKE_REQUEST
1187 &dev_attr_fail
.attr
,
1189 #ifdef CONFIG_FAIL_IO_TIMEOUT
1190 &dev_attr_fail_timeout
.attr
,
1195 static umode_t
disk_visible(struct kobject
*kobj
, struct attribute
*a
, int n
)
1197 struct device
*dev
= container_of(kobj
, typeof(*dev
), kobj
);
1198 struct gendisk
*disk
= dev_to_disk(dev
);
1200 if (a
== &dev_attr_badblocks
.attr
&& !disk
->bb
)
1205 static struct attribute_group disk_attr_group
= {
1206 .attrs
= disk_attrs
,
1207 .is_visible
= disk_visible
,
1210 static const struct attribute_group
*disk_attr_groups
[] = {
1216 * disk_replace_part_tbl - replace disk->part_tbl in RCU-safe way
1217 * @disk: disk to replace part_tbl for
1218 * @new_ptbl: new part_tbl to install
1220 * Replace disk->part_tbl with @new_ptbl in RCU-safe way. The
1221 * original ptbl is freed using RCU callback.
1224 * Matching bd_mutex locked or the caller is the only user of @disk.
1226 static void disk_replace_part_tbl(struct gendisk
*disk
,
1227 struct disk_part_tbl
*new_ptbl
)
1229 struct disk_part_tbl
*old_ptbl
=
1230 rcu_dereference_protected(disk
->part_tbl
, 1);
1232 rcu_assign_pointer(disk
->part_tbl
, new_ptbl
);
1235 rcu_assign_pointer(old_ptbl
->last_lookup
, NULL
);
1236 kfree_rcu(old_ptbl
, rcu_head
);
1241 * disk_expand_part_tbl - expand disk->part_tbl
1242 * @disk: disk to expand part_tbl for
1243 * @partno: expand such that this partno can fit in
1245 * Expand disk->part_tbl such that @partno can fit in. disk->part_tbl
1246 * uses RCU to allow unlocked dereferencing for stats and other stuff.
1249 * Matching bd_mutex locked or the caller is the only user of @disk.
1253 * 0 on success, -errno on failure.
1255 int disk_expand_part_tbl(struct gendisk
*disk
, int partno
)
1257 struct disk_part_tbl
*old_ptbl
=
1258 rcu_dereference_protected(disk
->part_tbl
, 1);
1259 struct disk_part_tbl
*new_ptbl
;
1260 int len
= old_ptbl
? old_ptbl
->len
: 0;
1265 * check for int overflow, since we can get here from blkpg_ioctl()
1266 * with a user passed 'partno'.
1268 target
= partno
+ 1;
1272 /* disk_max_parts() is zero during initialization, ignore if so */
1273 if (disk_max_parts(disk
) && target
> disk_max_parts(disk
))
1279 size
= sizeof(*new_ptbl
) + target
* sizeof(new_ptbl
->part
[0]);
1280 new_ptbl
= kzalloc_node(size
, GFP_KERNEL
, disk
->node_id
);
1284 new_ptbl
->len
= target
;
1286 for (i
= 0; i
< len
; i
++)
1287 rcu_assign_pointer(new_ptbl
->part
[i
], old_ptbl
->part
[i
]);
1289 disk_replace_part_tbl(disk
, new_ptbl
);
1293 static void disk_release(struct device
*dev
)
1295 struct gendisk
*disk
= dev_to_disk(dev
);
1297 blk_free_devt(dev
->devt
);
1298 disk_release_events(disk
);
1299 kfree(disk
->random
);
1300 disk_replace_part_tbl(disk
, NULL
);
1301 hd_free_part(&disk
->part0
);
1303 blk_put_queue(disk
->queue
);
1306 struct class block_class
= {
1310 static char *block_devnode(struct device
*dev
, umode_t
*mode
,
1311 kuid_t
*uid
, kgid_t
*gid
)
1313 struct gendisk
*disk
= dev_to_disk(dev
);
1316 return disk
->devnode(disk
, mode
);
1320 static const struct device_type disk_type
= {
1322 .groups
= disk_attr_groups
,
1323 .release
= disk_release
,
1324 .devnode
= block_devnode
,
1327 #ifdef CONFIG_PROC_FS
1329 * aggregate disk stat collector. Uses the same stats that the sysfs
1330 * entries do, above, but makes them available through one seq_file.
1332 * The output looks suspiciously like /proc/partitions with a bunch of
1335 static int diskstats_show(struct seq_file
*seqf
, void *v
)
1337 struct gendisk
*gp
= v
;
1338 struct disk_part_iter piter
;
1339 struct hd_struct
*hd
;
1340 char buf
[BDEVNAME_SIZE
];
1341 unsigned int inflight
;
1344 if (&disk_to_dev(gp)->kobj.entry == block_class.devices.next)
1345 seq_puts(seqf, "major minor name"
1346 " rio rmerge rsect ruse wio wmerge "
1347 "wsect wuse running use aveq"
1351 disk_part_iter_init(&piter
, gp
, DISK_PITER_INCL_EMPTY_PART0
);
1352 while ((hd
= disk_part_iter_next(&piter
))) {
1353 inflight
= part_in_flight(gp
->queue
, hd
);
1354 seq_printf(seqf
, "%4d %7d %s "
1359 MAJOR(part_devt(hd
)), MINOR(part_devt(hd
)),
1360 disk_name(gp
, hd
->partno
, buf
),
1361 part_stat_read(hd
, ios
[STAT_READ
]),
1362 part_stat_read(hd
, merges
[STAT_READ
]),
1363 part_stat_read(hd
, sectors
[STAT_READ
]),
1364 (unsigned int)part_stat_read_msecs(hd
, STAT_READ
),
1365 part_stat_read(hd
, ios
[STAT_WRITE
]),
1366 part_stat_read(hd
, merges
[STAT_WRITE
]),
1367 part_stat_read(hd
, sectors
[STAT_WRITE
]),
1368 (unsigned int)part_stat_read_msecs(hd
, STAT_WRITE
),
1370 jiffies_to_msecs(part_stat_read(hd
, io_ticks
)),
1371 jiffies_to_msecs(part_stat_read(hd
, time_in_queue
)),
1372 part_stat_read(hd
, ios
[STAT_DISCARD
]),
1373 part_stat_read(hd
, merges
[STAT_DISCARD
]),
1374 part_stat_read(hd
, sectors
[STAT_DISCARD
]),
1375 (unsigned int)part_stat_read_msecs(hd
, STAT_DISCARD
)
1378 disk_part_iter_exit(&piter
);
1383 static const struct seq_operations diskstats_op
= {
1384 .start
= disk_seqf_start
,
1385 .next
= disk_seqf_next
,
1386 .stop
= disk_seqf_stop
,
1387 .show
= diskstats_show
1390 static int __init
proc_genhd_init(void)
1392 proc_create_seq("diskstats", 0, NULL
, &diskstats_op
);
1393 proc_create_seq("partitions", 0, NULL
, &partitions_op
);
1396 module_init(proc_genhd_init
);
1397 #endif /* CONFIG_PROC_FS */
1399 dev_t
blk_lookup_devt(const char *name
, int partno
)
1401 dev_t devt
= MKDEV(0, 0);
1402 struct class_dev_iter iter
;
1405 class_dev_iter_init(&iter
, &block_class
, NULL
, &disk_type
);
1406 while ((dev
= class_dev_iter_next(&iter
))) {
1407 struct gendisk
*disk
= dev_to_disk(dev
);
1408 struct hd_struct
*part
;
1410 if (strcmp(dev_name(dev
), name
))
1413 if (partno
< disk
->minors
) {
1414 /* We need to return the right devno, even
1415 * if the partition doesn't exist yet.
1417 devt
= MKDEV(MAJOR(dev
->devt
),
1418 MINOR(dev
->devt
) + partno
);
1421 part
= disk_get_part(disk
, partno
);
1423 devt
= part_devt(part
);
1424 disk_put_part(part
);
1427 disk_put_part(part
);
1429 class_dev_iter_exit(&iter
);
1432 EXPORT_SYMBOL(blk_lookup_devt
);
1434 struct gendisk
*__alloc_disk_node(int minors
, int node_id
)
1436 struct gendisk
*disk
;
1437 struct disk_part_tbl
*ptbl
;
1439 if (minors
> DISK_MAX_PARTS
) {
1441 "block: can't allocate more than %d partitions\n",
1443 minors
= DISK_MAX_PARTS
;
1446 disk
= kzalloc_node(sizeof(struct gendisk
), GFP_KERNEL
, node_id
);
1448 if (!init_part_stats(&disk
->part0
)) {
1452 init_rwsem(&disk
->lookup_sem
);
1453 disk
->node_id
= node_id
;
1454 if (disk_expand_part_tbl(disk
, 0)) {
1455 free_part_stats(&disk
->part0
);
1459 ptbl
= rcu_dereference_protected(disk
->part_tbl
, 1);
1460 rcu_assign_pointer(ptbl
->part
[0], &disk
->part0
);
1463 * set_capacity() and get_capacity() currently don't use
1464 * seqcounter to read/update the part0->nr_sects. Still init
1465 * the counter as we can read the sectors in IO submission
1466 * patch using seqence counters.
1468 * TODO: Ideally set_capacity() and get_capacity() should be
1469 * converted to make use of bd_mutex and sequence counters.
1471 seqcount_init(&disk
->part0
.nr_sects_seq
);
1472 if (hd_ref_init(&disk
->part0
)) {
1473 hd_free_part(&disk
->part0
);
1478 disk
->minors
= minors
;
1479 rand_initialize_disk(disk
);
1480 disk_to_dev(disk
)->class = &block_class
;
1481 disk_to_dev(disk
)->type
= &disk_type
;
1482 device_initialize(disk_to_dev(disk
));
1486 EXPORT_SYMBOL(__alloc_disk_node
);
1488 struct kobject
*get_disk_and_module(struct gendisk
*disk
)
1490 struct module
*owner
;
1491 struct kobject
*kobj
;
1495 owner
= disk
->fops
->owner
;
1496 if (owner
&& !try_module_get(owner
))
1498 kobj
= kobject_get_unless_zero(&disk_to_dev(disk
)->kobj
);
1506 EXPORT_SYMBOL(get_disk_and_module
);
1508 void put_disk(struct gendisk
*disk
)
1511 kobject_put(&disk_to_dev(disk
)->kobj
);
1513 EXPORT_SYMBOL(put_disk
);
1516 * This is a counterpart of get_disk_and_module() and thus also of
1519 void put_disk_and_module(struct gendisk
*disk
)
1522 struct module
*owner
= disk
->fops
->owner
;
1528 EXPORT_SYMBOL(put_disk_and_module
);
1530 static void set_disk_ro_uevent(struct gendisk
*gd
, int ro
)
1532 char event
[] = "DISK_RO=1";
1533 char *envp
[] = { event
, NULL
};
1537 kobject_uevent_env(&disk_to_dev(gd
)->kobj
, KOBJ_CHANGE
, envp
);
1540 void set_device_ro(struct block_device
*bdev
, int flag
)
1542 bdev
->bd_part
->policy
= flag
;
1545 EXPORT_SYMBOL(set_device_ro
);
1547 void set_disk_ro(struct gendisk
*disk
, int flag
)
1549 struct disk_part_iter piter
;
1550 struct hd_struct
*part
;
1552 if (disk
->part0
.policy
!= flag
) {
1553 set_disk_ro_uevent(disk
, flag
);
1554 disk
->part0
.policy
= flag
;
1557 disk_part_iter_init(&piter
, disk
, DISK_PITER_INCL_EMPTY
);
1558 while ((part
= disk_part_iter_next(&piter
)))
1559 part
->policy
= flag
;
1560 disk_part_iter_exit(&piter
);
1563 EXPORT_SYMBOL(set_disk_ro
);
1565 int bdev_read_only(struct block_device
*bdev
)
1569 return bdev
->bd_part
->policy
;
1572 EXPORT_SYMBOL(bdev_read_only
);
1574 int invalidate_partition(struct gendisk
*disk
, int partno
)
1577 struct block_device
*bdev
= bdget_disk(disk
, partno
);
1580 res
= __invalidate_device(bdev
, true);
1586 EXPORT_SYMBOL(invalidate_partition
);
1589 * Disk events - monitor disk events like media change and eject request.
1591 struct disk_events
{
1592 struct list_head node
; /* all disk_event's */
1593 struct gendisk
*disk
; /* the associated disk */
1596 struct mutex block_mutex
; /* protects blocking */
1597 int block
; /* event blocking depth */
1598 unsigned int pending
; /* events already sent out */
1599 unsigned int clearing
; /* events being cleared */
1601 long poll_msecs
; /* interval, -1 for default */
1602 struct delayed_work dwork
;
1605 static const char *disk_events_strs
[] = {
1606 [ilog2(DISK_EVENT_MEDIA_CHANGE
)] = "media_change",
1607 [ilog2(DISK_EVENT_EJECT_REQUEST
)] = "eject_request",
1610 static char *disk_uevents
[] = {
1611 [ilog2(DISK_EVENT_MEDIA_CHANGE
)] = "DISK_MEDIA_CHANGE=1",
1612 [ilog2(DISK_EVENT_EJECT_REQUEST
)] = "DISK_EJECT_REQUEST=1",
1615 /* list of all disk_events */
1616 static DEFINE_MUTEX(disk_events_mutex
);
1617 static LIST_HEAD(disk_events
);
1619 /* disable in-kernel polling by default */
1620 static unsigned long disk_events_dfl_poll_msecs
;
1622 static unsigned long disk_events_poll_jiffies(struct gendisk
*disk
)
1624 struct disk_events
*ev
= disk
->ev
;
1625 long intv_msecs
= 0;
1628 * If device-specific poll interval is set, always use it. If
1629 * the default is being used, poll iff there are events which
1630 * can't be monitored asynchronously.
1632 if (ev
->poll_msecs
>= 0)
1633 intv_msecs
= ev
->poll_msecs
;
1634 else if (disk
->events
& ~disk
->async_events
)
1635 intv_msecs
= disk_events_dfl_poll_msecs
;
1637 return msecs_to_jiffies(intv_msecs
);
1641 * disk_block_events - block and flush disk event checking
1642 * @disk: disk to block events for
1644 * On return from this function, it is guaranteed that event checking
1645 * isn't in progress and won't happen until unblocked by
1646 * disk_unblock_events(). Events blocking is counted and the actual
1647 * unblocking happens after the matching number of unblocks are done.
1649 * Note that this intentionally does not block event checking from
1650 * disk_clear_events().
1655 void disk_block_events(struct gendisk
*disk
)
1657 struct disk_events
*ev
= disk
->ev
;
1658 unsigned long flags
;
1665 * Outer mutex ensures that the first blocker completes canceling
1666 * the event work before further blockers are allowed to finish.
1668 mutex_lock(&ev
->block_mutex
);
1670 spin_lock_irqsave(&ev
->lock
, flags
);
1671 cancel
= !ev
->block
++;
1672 spin_unlock_irqrestore(&ev
->lock
, flags
);
1675 cancel_delayed_work_sync(&disk
->ev
->dwork
);
1677 mutex_unlock(&ev
->block_mutex
);
1680 static void __disk_unblock_events(struct gendisk
*disk
, bool check_now
)
1682 struct disk_events
*ev
= disk
->ev
;
1684 unsigned long flags
;
1686 spin_lock_irqsave(&ev
->lock
, flags
);
1688 if (WARN_ON_ONCE(ev
->block
<= 0))
1694 intv
= disk_events_poll_jiffies(disk
);
1696 queue_delayed_work(system_freezable_power_efficient_wq
,
1699 queue_delayed_work(system_freezable_power_efficient_wq
,
1702 spin_unlock_irqrestore(&ev
->lock
, flags
);
1706 * disk_unblock_events - unblock disk event checking
1707 * @disk: disk to unblock events for
1709 * Undo disk_block_events(). When the block count reaches zero, it
1710 * starts events polling if configured.
1713 * Don't care. Safe to call from irq context.
1715 void disk_unblock_events(struct gendisk
*disk
)
1718 __disk_unblock_events(disk
, false);
1722 * disk_flush_events - schedule immediate event checking and flushing
1723 * @disk: disk to check and flush events for
1724 * @mask: events to flush
1726 * Schedule immediate event checking on @disk if not blocked. Events in
1727 * @mask are scheduled to be cleared from the driver. Note that this
1728 * doesn't clear the events from @disk->ev.
1731 * If @mask is non-zero must be called with bdev->bd_mutex held.
1733 void disk_flush_events(struct gendisk
*disk
, unsigned int mask
)
1735 struct disk_events
*ev
= disk
->ev
;
1740 spin_lock_irq(&ev
->lock
);
1741 ev
->clearing
|= mask
;
1743 mod_delayed_work(system_freezable_power_efficient_wq
,
1745 spin_unlock_irq(&ev
->lock
);
1749 * disk_clear_events - synchronously check, clear and return pending events
1750 * @disk: disk to fetch and clear events from
1751 * @mask: mask of events to be fetched and cleared
1753 * Disk events are synchronously checked and pending events in @mask
1754 * are cleared and returned. This ignores the block count.
1759 unsigned int disk_clear_events(struct gendisk
*disk
, unsigned int mask
)
1761 const struct block_device_operations
*bdops
= disk
->fops
;
1762 struct disk_events
*ev
= disk
->ev
;
1763 unsigned int pending
;
1764 unsigned int clearing
= mask
;
1767 /* for drivers still using the old ->media_changed method */
1768 if ((mask
& DISK_EVENT_MEDIA_CHANGE
) &&
1769 bdops
->media_changed
&& bdops
->media_changed(disk
))
1770 return DISK_EVENT_MEDIA_CHANGE
;
1774 disk_block_events(disk
);
1777 * store the union of mask and ev->clearing on the stack so that the
1778 * race with disk_flush_events does not cause ambiguity (ev->clearing
1779 * can still be modified even if events are blocked).
1781 spin_lock_irq(&ev
->lock
);
1782 clearing
|= ev
->clearing
;
1784 spin_unlock_irq(&ev
->lock
);
1786 disk_check_events(ev
, &clearing
);
1788 * if ev->clearing is not 0, the disk_flush_events got called in the
1789 * middle of this function, so we want to run the workfn without delay.
1791 __disk_unblock_events(disk
, ev
->clearing
? true : false);
1793 /* then, fetch and clear pending events */
1794 spin_lock_irq(&ev
->lock
);
1795 pending
= ev
->pending
& mask
;
1796 ev
->pending
&= ~mask
;
1797 spin_unlock_irq(&ev
->lock
);
1798 WARN_ON_ONCE(clearing
& mask
);
1804 * Separate this part out so that a different pointer for clearing_ptr can be
1805 * passed in for disk_clear_events.
1807 static void disk_events_workfn(struct work_struct
*work
)
1809 struct delayed_work
*dwork
= to_delayed_work(work
);
1810 struct disk_events
*ev
= container_of(dwork
, struct disk_events
, dwork
);
1812 disk_check_events(ev
, &ev
->clearing
);
1815 static void disk_check_events(struct disk_events
*ev
,
1816 unsigned int *clearing_ptr
)
1818 struct gendisk
*disk
= ev
->disk
;
1819 char *envp
[ARRAY_SIZE(disk_uevents
) + 1] = { };
1820 unsigned int clearing
= *clearing_ptr
;
1821 unsigned int events
;
1823 int nr_events
= 0, i
;
1826 events
= disk
->fops
->check_events(disk
, clearing
);
1828 /* accumulate pending events and schedule next poll if necessary */
1829 spin_lock_irq(&ev
->lock
);
1831 events
&= ~ev
->pending
;
1832 ev
->pending
|= events
;
1833 *clearing_ptr
&= ~clearing
;
1835 intv
= disk_events_poll_jiffies(disk
);
1836 if (!ev
->block
&& intv
)
1837 queue_delayed_work(system_freezable_power_efficient_wq
,
1840 spin_unlock_irq(&ev
->lock
);
1843 * Tell userland about new events. Only the events listed in
1844 * @disk->events are reported. Unlisted events are processed the
1845 * same internally but never get reported to userland.
1847 for (i
= 0; i
< ARRAY_SIZE(disk_uevents
); i
++)
1848 if (events
& disk
->events
& (1 << i
))
1849 envp
[nr_events
++] = disk_uevents
[i
];
1852 kobject_uevent_env(&disk_to_dev(disk
)->kobj
, KOBJ_CHANGE
, envp
);
1856 * A disk events enabled device has the following sysfs nodes under
1857 * its /sys/block/X/ directory.
1859 * events : list of all supported events
1860 * events_async : list of events which can be detected w/o polling
1861 * events_poll_msecs : polling interval, 0: disable, -1: system default
1863 static ssize_t
__disk_events_show(unsigned int events
, char *buf
)
1865 const char *delim
= "";
1869 for (i
= 0; i
< ARRAY_SIZE(disk_events_strs
); i
++)
1870 if (events
& (1 << i
)) {
1871 pos
+= sprintf(buf
+ pos
, "%s%s",
1872 delim
, disk_events_strs
[i
]);
1876 pos
+= sprintf(buf
+ pos
, "\n");
1880 static ssize_t
disk_events_show(struct device
*dev
,
1881 struct device_attribute
*attr
, char *buf
)
1883 struct gendisk
*disk
= dev_to_disk(dev
);
1885 return __disk_events_show(disk
->events
, buf
);
1888 static ssize_t
disk_events_async_show(struct device
*dev
,
1889 struct device_attribute
*attr
, char *buf
)
1891 struct gendisk
*disk
= dev_to_disk(dev
);
1893 return __disk_events_show(disk
->async_events
, buf
);
1896 static ssize_t
disk_events_poll_msecs_show(struct device
*dev
,
1897 struct device_attribute
*attr
,
1900 struct gendisk
*disk
= dev_to_disk(dev
);
1902 return sprintf(buf
, "%ld\n", disk
->ev
->poll_msecs
);
1905 static ssize_t
disk_events_poll_msecs_store(struct device
*dev
,
1906 struct device_attribute
*attr
,
1907 const char *buf
, size_t count
)
1909 struct gendisk
*disk
= dev_to_disk(dev
);
1912 if (!count
|| !sscanf(buf
, "%ld", &intv
))
1915 if (intv
< 0 && intv
!= -1)
1918 disk_block_events(disk
);
1919 disk
->ev
->poll_msecs
= intv
;
1920 __disk_unblock_events(disk
, true);
1925 static const DEVICE_ATTR(events
, 0444, disk_events_show
, NULL
);
1926 static const DEVICE_ATTR(events_async
, 0444, disk_events_async_show
, NULL
);
1927 static const DEVICE_ATTR(events_poll_msecs
, 0644,
1928 disk_events_poll_msecs_show
,
1929 disk_events_poll_msecs_store
);
1931 static const struct attribute
*disk_events_attrs
[] = {
1932 &dev_attr_events
.attr
,
1933 &dev_attr_events_async
.attr
,
1934 &dev_attr_events_poll_msecs
.attr
,
1939 * The default polling interval can be specified by the kernel
1940 * parameter block.events_dfl_poll_msecs which defaults to 0
1941 * (disable). This can also be modified runtime by writing to
1942 * /sys/module/block/events_dfl_poll_msecs.
1944 static int disk_events_set_dfl_poll_msecs(const char *val
,
1945 const struct kernel_param
*kp
)
1947 struct disk_events
*ev
;
1950 ret
= param_set_ulong(val
, kp
);
1954 mutex_lock(&disk_events_mutex
);
1956 list_for_each_entry(ev
, &disk_events
, node
)
1957 disk_flush_events(ev
->disk
, 0);
1959 mutex_unlock(&disk_events_mutex
);
1964 static const struct kernel_param_ops disk_events_dfl_poll_msecs_param_ops
= {
1965 .set
= disk_events_set_dfl_poll_msecs
,
1966 .get
= param_get_ulong
,
1969 #undef MODULE_PARAM_PREFIX
1970 #define MODULE_PARAM_PREFIX "block."
1972 module_param_cb(events_dfl_poll_msecs
, &disk_events_dfl_poll_msecs_param_ops
,
1973 &disk_events_dfl_poll_msecs
, 0644);
1976 * disk_{alloc|add|del|release}_events - initialize and destroy disk_events.
1978 static void disk_alloc_events(struct gendisk
*disk
)
1980 struct disk_events
*ev
;
1982 if (!disk
->fops
->check_events
)
1985 ev
= kzalloc(sizeof(*ev
), GFP_KERNEL
);
1987 pr_warn("%s: failed to initialize events\n", disk
->disk_name
);
1991 INIT_LIST_HEAD(&ev
->node
);
1993 spin_lock_init(&ev
->lock
);
1994 mutex_init(&ev
->block_mutex
);
1996 ev
->poll_msecs
= -1;
1997 INIT_DELAYED_WORK(&ev
->dwork
, disk_events_workfn
);
2002 static void disk_add_events(struct gendisk
*disk
)
2007 /* FIXME: error handling */
2008 if (sysfs_create_files(&disk_to_dev(disk
)->kobj
, disk_events_attrs
) < 0)
2009 pr_warn("%s: failed to create sysfs files for events\n",
2012 mutex_lock(&disk_events_mutex
);
2013 list_add_tail(&disk
->ev
->node
, &disk_events
);
2014 mutex_unlock(&disk_events_mutex
);
2017 * Block count is initialized to 1 and the following initial
2018 * unblock kicks it into action.
2020 __disk_unblock_events(disk
, true);
2023 static void disk_del_events(struct gendisk
*disk
)
2028 disk_block_events(disk
);
2030 mutex_lock(&disk_events_mutex
);
2031 list_del_init(&disk
->ev
->node
);
2032 mutex_unlock(&disk_events_mutex
);
2034 sysfs_remove_files(&disk_to_dev(disk
)->kobj
, disk_events_attrs
);
2037 static void disk_release_events(struct gendisk
*disk
)
2039 /* the block count should be 1 from disk_del_events() */
2040 WARN_ON_ONCE(disk
->ev
&& disk
->ev
->block
!= 1);