2 * Copyright (C) 2001, 2002 Sistina Software (UK) Limited.
3 * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved.
5 * This file is released under the GPL.
11 #include <linux/init.h>
12 #include <linux/module.h>
13 #include <linux/mutex.h>
14 #include <linux/moduleparam.h>
15 #include <linux/blkpg.h>
16 #include <linux/bio.h>
17 #include <linux/mempool.h>
18 #include <linux/slab.h>
19 #include <linux/idr.h>
20 #include <linux/hdreg.h>
21 #include <linux/delay.h>
22 #include <linux/wait.h>
23 #include <linux/kthread.h>
24 #include <linux/ktime.h>
25 #include <linux/elevator.h> /* for rq_end_sector() */
26 #include <linux/blk-mq.h>
29 #include <trace/events/block.h>
31 #define DM_MSG_PREFIX "core"
35 * ratelimit state to be used in DMXXX_LIMIT().
37 DEFINE_RATELIMIT_STATE(dm_ratelimit_state
,
38 DEFAULT_RATELIMIT_INTERVAL
,
39 DEFAULT_RATELIMIT_BURST
);
40 EXPORT_SYMBOL(dm_ratelimit_state
);
44 * Cookies are numeric values sent with CHANGE and REMOVE
45 * uevents while resuming, removing or renaming the device.
47 #define DM_COOKIE_ENV_VAR_NAME "DM_COOKIE"
48 #define DM_COOKIE_LENGTH 24
50 static const char *_name
= DM_NAME
;
52 static unsigned int major
= 0;
53 static unsigned int _major
= 0;
55 static DEFINE_IDR(_minor_idr
);
57 static DEFINE_SPINLOCK(_minor_lock
);
59 static void do_deferred_remove(struct work_struct
*w
);
61 static DECLARE_WORK(deferred_remove_work
, do_deferred_remove
);
63 static struct workqueue_struct
*deferred_remove_workqueue
;
67 * One of these is allocated per bio.
70 struct mapped_device
*md
;
74 unsigned long start_time
;
75 spinlock_t endio_lock
;
76 struct dm_stats_aux stats_aux
;
80 * For request-based dm.
81 * One of these is allocated per request.
83 struct dm_rq_target_io
{
84 struct mapped_device
*md
;
86 struct request
*orig
, *clone
;
87 struct kthread_work work
;
90 struct dm_stats_aux stats_aux
;
91 unsigned long duration_jiffies
;
96 * For request-based dm - the bio clones we allocate are embedded in these
99 * We allocate these with bio_alloc_bioset, using the front_pad parameter when
100 * the bioset is created - this means the bio has to come at the end of the
103 struct dm_rq_clone_bio_info
{
105 struct dm_rq_target_io
*tio
;
109 union map_info
*dm_get_rq_mapinfo(struct request
*rq
)
111 if (rq
&& rq
->end_io_data
)
112 return &((struct dm_rq_target_io
*)rq
->end_io_data
)->info
;
115 EXPORT_SYMBOL_GPL(dm_get_rq_mapinfo
);
117 #define MINOR_ALLOCED ((void *)-1)
120 * Bits for the md->flags field.
122 #define DMF_BLOCK_IO_FOR_SUSPEND 0
123 #define DMF_SUSPENDED 1
125 #define DMF_FREEING 3
126 #define DMF_DELETING 4
127 #define DMF_NOFLUSH_SUSPENDING 5
128 #define DMF_DEFERRED_REMOVE 6
129 #define DMF_SUSPENDED_INTERNALLY 7
132 * A dummy definition to make RCU happy.
133 * struct dm_table should never be dereferenced in this file.
140 * Work processed by per-device workqueue.
142 struct mapped_device
{
143 struct srcu_struct io_barrier
;
144 struct mutex suspend_lock
;
149 * The current mapping.
150 * Use dm_get_live_table{_fast} or take suspend_lock for
153 struct dm_table __rcu
*map
;
155 struct list_head table_devices
;
156 struct mutex table_devices_lock
;
160 struct request_queue
*queue
;
162 /* Protect queue and type against concurrent access. */
163 struct mutex type_lock
;
165 struct target_type
*immutable_target_type
;
167 struct gendisk
*disk
;
173 * A list of ios that arrived while we were suspended.
176 wait_queue_head_t wait
;
177 struct work_struct work
;
178 struct bio_list deferred
;
179 spinlock_t deferred_lock
;
182 * Processing queue (flush)
184 struct workqueue_struct
*wq
;
187 * io objects are allocated from here.
198 wait_queue_head_t eventq
;
200 struct list_head uevent_list
;
201 spinlock_t uevent_lock
; /* Protect access to uevent_list */
204 * freeze/thaw support require holding onto a super block
206 struct super_block
*frozen_sb
;
207 struct block_device
*bdev
;
209 /* forced geometry settings */
210 struct hd_geometry geometry
;
212 /* kobject and completion */
213 struct dm_kobject_holder kobj_holder
;
215 /* zero-length flush that will be cloned and submitted to targets */
216 struct bio flush_bio
;
218 /* the number of internal suspends */
219 unsigned internal_suspend_count
;
221 struct dm_stats stats
;
223 struct kthread_worker kworker
;
224 struct task_struct
*kworker_task
;
226 /* for request-based merge heuristic in dm_request_fn() */
227 unsigned seq_rq_merge_deadline_usecs
;
229 sector_t last_rq_pos
;
230 ktime_t last_rq_start_time
;
232 /* for blk-mq request-based DM support */
233 struct blk_mq_tag_set tag_set
;
237 #ifdef CONFIG_DM_MQ_DEFAULT
238 static bool use_blk_mq
= true;
240 static bool use_blk_mq
= false;
243 bool dm_use_blk_mq(struct mapped_device
*md
)
245 return md
->use_blk_mq
;
249 * For mempools pre-allocation at the table loading time.
251 struct dm_md_mempools
{
257 struct table_device
{
258 struct list_head list
;
260 struct dm_dev dm_dev
;
263 #define RESERVED_BIO_BASED_IOS 16
264 #define RESERVED_REQUEST_BASED_IOS 256
265 #define RESERVED_MAX_IOS 1024
266 static struct kmem_cache
*_io_cache
;
267 static struct kmem_cache
*_rq_tio_cache
;
268 static struct kmem_cache
*_rq_cache
;
271 * Bio-based DM's mempools' reserved IOs set by the user.
273 static unsigned reserved_bio_based_ios
= RESERVED_BIO_BASED_IOS
;
276 * Request-based DM's mempools' reserved IOs set by the user.
278 static unsigned reserved_rq_based_ios
= RESERVED_REQUEST_BASED_IOS
;
280 static unsigned __dm_get_module_param(unsigned *module_param
,
281 unsigned def
, unsigned max
)
283 unsigned param
= ACCESS_ONCE(*module_param
);
284 unsigned modified_param
= 0;
287 modified_param
= def
;
288 else if (param
> max
)
289 modified_param
= max
;
291 if (modified_param
) {
292 (void)cmpxchg(module_param
, param
, modified_param
);
293 param
= modified_param
;
299 unsigned dm_get_reserved_bio_based_ios(void)
301 return __dm_get_module_param(&reserved_bio_based_ios
,
302 RESERVED_BIO_BASED_IOS
, RESERVED_MAX_IOS
);
304 EXPORT_SYMBOL_GPL(dm_get_reserved_bio_based_ios
);
306 unsigned dm_get_reserved_rq_based_ios(void)
308 return __dm_get_module_param(&reserved_rq_based_ios
,
309 RESERVED_REQUEST_BASED_IOS
, RESERVED_MAX_IOS
);
311 EXPORT_SYMBOL_GPL(dm_get_reserved_rq_based_ios
);
313 static int __init
local_init(void)
317 /* allocate a slab for the dm_ios */
318 _io_cache
= KMEM_CACHE(dm_io
, 0);
322 _rq_tio_cache
= KMEM_CACHE(dm_rq_target_io
, 0);
324 goto out_free_io_cache
;
326 _rq_cache
= kmem_cache_create("dm_clone_request", sizeof(struct request
),
327 __alignof__(struct request
), 0, NULL
);
329 goto out_free_rq_tio_cache
;
331 r
= dm_uevent_init();
333 goto out_free_rq_cache
;
335 deferred_remove_workqueue
= alloc_workqueue("kdmremove", WQ_UNBOUND
, 1);
336 if (!deferred_remove_workqueue
) {
338 goto out_uevent_exit
;
342 r
= register_blkdev(_major
, _name
);
344 goto out_free_workqueue
;
352 destroy_workqueue(deferred_remove_workqueue
);
356 kmem_cache_destroy(_rq_cache
);
357 out_free_rq_tio_cache
:
358 kmem_cache_destroy(_rq_tio_cache
);
360 kmem_cache_destroy(_io_cache
);
365 static void local_exit(void)
367 flush_scheduled_work();
368 destroy_workqueue(deferred_remove_workqueue
);
370 kmem_cache_destroy(_rq_cache
);
371 kmem_cache_destroy(_rq_tio_cache
);
372 kmem_cache_destroy(_io_cache
);
373 unregister_blkdev(_major
, _name
);
378 DMINFO("cleaned up");
381 static int (*_inits
[])(void) __initdata
= {
392 static void (*_exits
[])(void) = {
403 static int __init
dm_init(void)
405 const int count
= ARRAY_SIZE(_inits
);
409 for (i
= 0; i
< count
; i
++) {
424 static void __exit
dm_exit(void)
426 int i
= ARRAY_SIZE(_exits
);
432 * Should be empty by this point.
434 idr_destroy(&_minor_idr
);
438 * Block device functions
440 int dm_deleting_md(struct mapped_device
*md
)
442 return test_bit(DMF_DELETING
, &md
->flags
);
445 static int dm_blk_open(struct block_device
*bdev
, fmode_t mode
)
447 struct mapped_device
*md
;
449 spin_lock(&_minor_lock
);
451 md
= bdev
->bd_disk
->private_data
;
455 if (test_bit(DMF_FREEING
, &md
->flags
) ||
456 dm_deleting_md(md
)) {
462 atomic_inc(&md
->open_count
);
464 spin_unlock(&_minor_lock
);
466 return md
? 0 : -ENXIO
;
469 static void dm_blk_close(struct gendisk
*disk
, fmode_t mode
)
471 struct mapped_device
*md
;
473 spin_lock(&_minor_lock
);
475 md
= disk
->private_data
;
479 if (atomic_dec_and_test(&md
->open_count
) &&
480 (test_bit(DMF_DEFERRED_REMOVE
, &md
->flags
)))
481 queue_work(deferred_remove_workqueue
, &deferred_remove_work
);
485 spin_unlock(&_minor_lock
);
488 int dm_open_count(struct mapped_device
*md
)
490 return atomic_read(&md
->open_count
);
494 * Guarantees nothing is using the device before it's deleted.
496 int dm_lock_for_deletion(struct mapped_device
*md
, bool mark_deferred
, bool only_deferred
)
500 spin_lock(&_minor_lock
);
502 if (dm_open_count(md
)) {
505 set_bit(DMF_DEFERRED_REMOVE
, &md
->flags
);
506 } else if (only_deferred
&& !test_bit(DMF_DEFERRED_REMOVE
, &md
->flags
))
509 set_bit(DMF_DELETING
, &md
->flags
);
511 spin_unlock(&_minor_lock
);
516 int dm_cancel_deferred_remove(struct mapped_device
*md
)
520 spin_lock(&_minor_lock
);
522 if (test_bit(DMF_DELETING
, &md
->flags
))
525 clear_bit(DMF_DEFERRED_REMOVE
, &md
->flags
);
527 spin_unlock(&_minor_lock
);
532 static void do_deferred_remove(struct work_struct
*w
)
534 dm_deferred_remove();
537 sector_t
dm_get_size(struct mapped_device
*md
)
539 return get_capacity(md
->disk
);
542 struct request_queue
*dm_get_md_queue(struct mapped_device
*md
)
547 struct dm_stats
*dm_get_stats(struct mapped_device
*md
)
552 static int dm_blk_getgeo(struct block_device
*bdev
, struct hd_geometry
*geo
)
554 struct mapped_device
*md
= bdev
->bd_disk
->private_data
;
556 return dm_get_geometry(md
, geo
);
559 static int dm_get_live_table_for_ioctl(struct mapped_device
*md
,
560 struct dm_target
**tgt
, struct block_device
**bdev
,
561 fmode_t
*mode
, int *srcu_idx
)
563 struct dm_table
*map
;
568 map
= dm_get_live_table(md
, srcu_idx
);
569 if (!map
|| !dm_table_get_size(map
))
572 /* We only support devices that have a single target */
573 if (dm_table_get_num_targets(map
) != 1)
576 *tgt
= dm_table_get_target(map
, 0);
578 if (!(*tgt
)->type
->prepare_ioctl
)
581 if (dm_suspended_md(md
)) {
586 r
= (*tgt
)->type
->prepare_ioctl(*tgt
, bdev
, mode
);
593 dm_put_live_table(md
, *srcu_idx
);
594 if (r
== -ENOTCONN
&& !fatal_signal_pending(current
)) {
601 static int dm_blk_ioctl(struct block_device
*bdev
, fmode_t mode
,
602 unsigned int cmd
, unsigned long arg
)
604 struct mapped_device
*md
= bdev
->bd_disk
->private_data
;
605 struct dm_target
*tgt
;
606 struct block_device
*tgt_bdev
= NULL
;
609 r
= dm_get_live_table_for_ioctl(md
, &tgt
, &tgt_bdev
, &mode
, &srcu_idx
);
615 * Target determined this ioctl is being issued against
616 * a logical partition of the parent bdev; so extra
617 * validation is needed.
619 r
= scsi_verify_blk_ioctl(NULL
, cmd
);
624 r
= __blkdev_driver_ioctl(tgt_bdev
, mode
, cmd
, arg
);
626 dm_put_live_table(md
, srcu_idx
);
630 static struct dm_io
*alloc_io(struct mapped_device
*md
)
632 return mempool_alloc(md
->io_pool
, GFP_NOIO
);
635 static void free_io(struct mapped_device
*md
, struct dm_io
*io
)
637 mempool_free(io
, md
->io_pool
);
640 static void free_tio(struct mapped_device
*md
, struct dm_target_io
*tio
)
642 bio_put(&tio
->clone
);
645 static struct dm_rq_target_io
*alloc_rq_tio(struct mapped_device
*md
,
648 return mempool_alloc(md
->io_pool
, gfp_mask
);
651 static void free_rq_tio(struct dm_rq_target_io
*tio
)
653 mempool_free(tio
, tio
->md
->io_pool
);
656 static struct request
*alloc_clone_request(struct mapped_device
*md
,
659 return mempool_alloc(md
->rq_pool
, gfp_mask
);
662 static void free_clone_request(struct mapped_device
*md
, struct request
*rq
)
664 mempool_free(rq
, md
->rq_pool
);
667 static int md_in_flight(struct mapped_device
*md
)
669 return atomic_read(&md
->pending
[READ
]) +
670 atomic_read(&md
->pending
[WRITE
]);
673 static void start_io_acct(struct dm_io
*io
)
675 struct mapped_device
*md
= io
->md
;
676 struct bio
*bio
= io
->bio
;
678 int rw
= bio_data_dir(bio
);
680 io
->start_time
= jiffies
;
682 cpu
= part_stat_lock();
683 part_round_stats(cpu
, &dm_disk(md
)->part0
);
685 atomic_set(&dm_disk(md
)->part0
.in_flight
[rw
],
686 atomic_inc_return(&md
->pending
[rw
]));
688 if (unlikely(dm_stats_used(&md
->stats
)))
689 dm_stats_account_io(&md
->stats
, bio
->bi_rw
, bio
->bi_iter
.bi_sector
,
690 bio_sectors(bio
), false, 0, &io
->stats_aux
);
693 static void end_io_acct(struct dm_io
*io
)
695 struct mapped_device
*md
= io
->md
;
696 struct bio
*bio
= io
->bio
;
697 unsigned long duration
= jiffies
- io
->start_time
;
699 int rw
= bio_data_dir(bio
);
701 generic_end_io_acct(rw
, &dm_disk(md
)->part0
, io
->start_time
);
703 if (unlikely(dm_stats_used(&md
->stats
)))
704 dm_stats_account_io(&md
->stats
, bio
->bi_rw
, bio
->bi_iter
.bi_sector
,
705 bio_sectors(bio
), true, duration
, &io
->stats_aux
);
708 * After this is decremented the bio must not be touched if it is
711 pending
= atomic_dec_return(&md
->pending
[rw
]);
712 atomic_set(&dm_disk(md
)->part0
.in_flight
[rw
], pending
);
713 pending
+= atomic_read(&md
->pending
[rw
^0x1]);
715 /* nudge anyone waiting on suspend queue */
721 * Add the bio to the list of deferred io.
723 static void queue_io(struct mapped_device
*md
, struct bio
*bio
)
727 spin_lock_irqsave(&md
->deferred_lock
, flags
);
728 bio_list_add(&md
->deferred
, bio
);
729 spin_unlock_irqrestore(&md
->deferred_lock
, flags
);
730 queue_work(md
->wq
, &md
->work
);
734 * Everyone (including functions in this file), should use this
735 * function to access the md->map field, and make sure they call
736 * dm_put_live_table() when finished.
738 struct dm_table
*dm_get_live_table(struct mapped_device
*md
, int *srcu_idx
) __acquires(md
->io_barrier
)
740 *srcu_idx
= srcu_read_lock(&md
->io_barrier
);
742 return srcu_dereference(md
->map
, &md
->io_barrier
);
745 void dm_put_live_table(struct mapped_device
*md
, int srcu_idx
) __releases(md
->io_barrier
)
747 srcu_read_unlock(&md
->io_barrier
, srcu_idx
);
750 void dm_sync_table(struct mapped_device
*md
)
752 synchronize_srcu(&md
->io_barrier
);
753 synchronize_rcu_expedited();
757 * A fast alternative to dm_get_live_table/dm_put_live_table.
758 * The caller must not block between these two functions.
760 static struct dm_table
*dm_get_live_table_fast(struct mapped_device
*md
) __acquires(RCU
)
763 return rcu_dereference(md
->map
);
766 static void dm_put_live_table_fast(struct mapped_device
*md
) __releases(RCU
)
772 * Open a table device so we can use it as a map destination.
774 static int open_table_device(struct table_device
*td
, dev_t dev
,
775 struct mapped_device
*md
)
777 static char *_claim_ptr
= "I belong to device-mapper";
778 struct block_device
*bdev
;
782 BUG_ON(td
->dm_dev
.bdev
);
784 bdev
= blkdev_get_by_dev(dev
, td
->dm_dev
.mode
| FMODE_EXCL
, _claim_ptr
);
786 return PTR_ERR(bdev
);
788 r
= bd_link_disk_holder(bdev
, dm_disk(md
));
790 blkdev_put(bdev
, td
->dm_dev
.mode
| FMODE_EXCL
);
794 td
->dm_dev
.bdev
= bdev
;
799 * Close a table device that we've been using.
801 static void close_table_device(struct table_device
*td
, struct mapped_device
*md
)
803 if (!td
->dm_dev
.bdev
)
806 bd_unlink_disk_holder(td
->dm_dev
.bdev
, dm_disk(md
));
807 blkdev_put(td
->dm_dev
.bdev
, td
->dm_dev
.mode
| FMODE_EXCL
);
808 td
->dm_dev
.bdev
= NULL
;
811 static struct table_device
*find_table_device(struct list_head
*l
, dev_t dev
,
813 struct table_device
*td
;
815 list_for_each_entry(td
, l
, list
)
816 if (td
->dm_dev
.bdev
->bd_dev
== dev
&& td
->dm_dev
.mode
== mode
)
822 int dm_get_table_device(struct mapped_device
*md
, dev_t dev
, fmode_t mode
,
823 struct dm_dev
**result
) {
825 struct table_device
*td
;
827 mutex_lock(&md
->table_devices_lock
);
828 td
= find_table_device(&md
->table_devices
, dev
, mode
);
830 td
= kmalloc(sizeof(*td
), GFP_KERNEL
);
832 mutex_unlock(&md
->table_devices_lock
);
836 td
->dm_dev
.mode
= mode
;
837 td
->dm_dev
.bdev
= NULL
;
839 if ((r
= open_table_device(td
, dev
, md
))) {
840 mutex_unlock(&md
->table_devices_lock
);
845 format_dev_t(td
->dm_dev
.name
, dev
);
847 atomic_set(&td
->count
, 0);
848 list_add(&td
->list
, &md
->table_devices
);
850 atomic_inc(&td
->count
);
851 mutex_unlock(&md
->table_devices_lock
);
853 *result
= &td
->dm_dev
;
856 EXPORT_SYMBOL_GPL(dm_get_table_device
);
858 void dm_put_table_device(struct mapped_device
*md
, struct dm_dev
*d
)
860 struct table_device
*td
= container_of(d
, struct table_device
, dm_dev
);
862 mutex_lock(&md
->table_devices_lock
);
863 if (atomic_dec_and_test(&td
->count
)) {
864 close_table_device(td
, md
);
868 mutex_unlock(&md
->table_devices_lock
);
870 EXPORT_SYMBOL(dm_put_table_device
);
872 static void free_table_devices(struct list_head
*devices
)
874 struct list_head
*tmp
, *next
;
876 list_for_each_safe(tmp
, next
, devices
) {
877 struct table_device
*td
= list_entry(tmp
, struct table_device
, list
);
879 DMWARN("dm_destroy: %s still exists with %d references",
880 td
->dm_dev
.name
, atomic_read(&td
->count
));
886 * Get the geometry associated with a dm device
888 int dm_get_geometry(struct mapped_device
*md
, struct hd_geometry
*geo
)
896 * Set the geometry of a device.
898 int dm_set_geometry(struct mapped_device
*md
, struct hd_geometry
*geo
)
900 sector_t sz
= (sector_t
)geo
->cylinders
* geo
->heads
* geo
->sectors
;
902 if (geo
->start
> sz
) {
903 DMWARN("Start sector is beyond the geometry limits.");
912 /*-----------------------------------------------------------------
914 * A more elegant soln is in the works that uses the queue
915 * merge fn, unfortunately there are a couple of changes to
916 * the block layer that I want to make for this. So in the
917 * interests of getting something for people to use I give
918 * you this clearly demarcated crap.
919 *---------------------------------------------------------------*/
921 static int __noflush_suspending(struct mapped_device
*md
)
923 return test_bit(DMF_NOFLUSH_SUSPENDING
, &md
->flags
);
927 * Decrements the number of outstanding ios that a bio has been
928 * cloned into, completing the original io if necc.
930 static void dec_pending(struct dm_io
*io
, int error
)
935 struct mapped_device
*md
= io
->md
;
937 /* Push-back supersedes any I/O errors */
938 if (unlikely(error
)) {
939 spin_lock_irqsave(&io
->endio_lock
, flags
);
940 if (!(io
->error
> 0 && __noflush_suspending(md
)))
942 spin_unlock_irqrestore(&io
->endio_lock
, flags
);
945 if (atomic_dec_and_test(&io
->io_count
)) {
946 if (io
->error
== DM_ENDIO_REQUEUE
) {
948 * Target requested pushing back the I/O.
950 spin_lock_irqsave(&md
->deferred_lock
, flags
);
951 if (__noflush_suspending(md
))
952 bio_list_add_head(&md
->deferred
, io
->bio
);
954 /* noflush suspend was interrupted. */
956 spin_unlock_irqrestore(&md
->deferred_lock
, flags
);
959 io_error
= io
->error
;
964 if (io_error
== DM_ENDIO_REQUEUE
)
967 if ((bio
->bi_rw
& REQ_FLUSH
) && bio
->bi_iter
.bi_size
) {
969 * Preflush done for flush with data, reissue
972 bio
->bi_rw
&= ~REQ_FLUSH
;
975 /* done with normal IO or empty flush */
976 trace_block_bio_complete(md
->queue
, bio
, io_error
);
977 bio
->bi_error
= io_error
;
983 static void disable_write_same(struct mapped_device
*md
)
985 struct queue_limits
*limits
= dm_get_queue_limits(md
);
987 /* device doesn't really support WRITE SAME, disable it */
988 limits
->max_write_same_sectors
= 0;
991 static void clone_endio(struct bio
*bio
)
993 int error
= bio
->bi_error
;
995 struct dm_target_io
*tio
= container_of(bio
, struct dm_target_io
, clone
);
996 struct dm_io
*io
= tio
->io
;
997 struct mapped_device
*md
= tio
->io
->md
;
998 dm_endio_fn endio
= tio
->ti
->type
->end_io
;
1001 r
= endio(tio
->ti
, bio
, error
);
1002 if (r
< 0 || r
== DM_ENDIO_REQUEUE
)
1004 * error and requeue request are handled
1008 else if (r
== DM_ENDIO_INCOMPLETE
)
1009 /* The target will handle the io */
1012 DMWARN("unimplemented target endio return value: %d", r
);
1017 if (unlikely(r
== -EREMOTEIO
&& (bio
->bi_rw
& REQ_WRITE_SAME
) &&
1018 !bdev_get_queue(bio
->bi_bdev
)->limits
.max_write_same_sectors
))
1019 disable_write_same(md
);
1022 dec_pending(io
, error
);
1026 * Partial completion handling for request-based dm
1028 static void end_clone_bio(struct bio
*clone
)
1030 struct dm_rq_clone_bio_info
*info
=
1031 container_of(clone
, struct dm_rq_clone_bio_info
, clone
);
1032 struct dm_rq_target_io
*tio
= info
->tio
;
1033 struct bio
*bio
= info
->orig
;
1034 unsigned int nr_bytes
= info
->orig
->bi_iter
.bi_size
;
1035 int error
= clone
->bi_error
;
1041 * An error has already been detected on the request.
1042 * Once error occurred, just let clone->end_io() handle
1048 * Don't notice the error to the upper layer yet.
1049 * The error handling decision is made by the target driver,
1050 * when the request is completed.
1057 * I/O for the bio successfully completed.
1058 * Notice the data completion to the upper layer.
1062 * bios are processed from the head of the list.
1063 * So the completing bio should always be rq->bio.
1064 * If it's not, something wrong is happening.
1066 if (tio
->orig
->bio
!= bio
)
1067 DMERR("bio completion is going in the middle of the request");
1070 * Update the original request.
1071 * Do not use blk_end_request() here, because it may complete
1072 * the original request before the clone, and break the ordering.
1074 blk_update_request(tio
->orig
, 0, nr_bytes
);
1077 static struct dm_rq_target_io
*tio_from_request(struct request
*rq
)
1079 return (rq
->q
->mq_ops
? blk_mq_rq_to_pdu(rq
) : rq
->special
);
1082 static void rq_end_stats(struct mapped_device
*md
, struct request
*orig
)
1084 if (unlikely(dm_stats_used(&md
->stats
))) {
1085 struct dm_rq_target_io
*tio
= tio_from_request(orig
);
1086 tio
->duration_jiffies
= jiffies
- tio
->duration_jiffies
;
1087 dm_stats_account_io(&md
->stats
, orig
->cmd_flags
, blk_rq_pos(orig
),
1088 tio
->n_sectors
, true, tio
->duration_jiffies
,
1094 * Don't touch any member of the md after calling this function because
1095 * the md may be freed in dm_put() at the end of this function.
1096 * Or do dm_get() before calling this function and dm_put() later.
1098 static void rq_completed(struct mapped_device
*md
, int rw
, bool run_queue
)
1100 atomic_dec(&md
->pending
[rw
]);
1102 /* nudge anyone waiting on suspend queue */
1103 if (!md_in_flight(md
))
1107 * Run this off this callpath, as drivers could invoke end_io while
1108 * inside their request_fn (and holding the queue lock). Calling
1109 * back into ->request_fn() could deadlock attempting to grab the
1113 if (md
->queue
->mq_ops
)
1114 blk_mq_run_hw_queues(md
->queue
, true);
1116 blk_run_queue_async(md
->queue
);
1120 * dm_put() must be at the end of this function. See the comment above
1125 static void free_rq_clone(struct request
*clone
)
1127 struct dm_rq_target_io
*tio
= clone
->end_io_data
;
1128 struct mapped_device
*md
= tio
->md
;
1130 blk_rq_unprep_clone(clone
);
1132 if (md
->type
== DM_TYPE_MQ_REQUEST_BASED
)
1133 /* stacked on blk-mq queue(s) */
1134 tio
->ti
->type
->release_clone_rq(clone
);
1135 else if (!md
->queue
->mq_ops
)
1136 /* request_fn queue stacked on request_fn queue(s) */
1137 free_clone_request(md
, clone
);
1139 * NOTE: for the blk-mq queue stacked on request_fn queue(s) case:
1140 * no need to call free_clone_request() because we leverage blk-mq by
1141 * allocating the clone at the end of the blk-mq pdu (see: clone_rq)
1144 if (!md
->queue
->mq_ops
)
1149 * Complete the clone and the original request.
1150 * Must be called without clone's queue lock held,
1151 * see end_clone_request() for more details.
1153 static void dm_end_request(struct request
*clone
, int error
)
1155 int rw
= rq_data_dir(clone
);
1156 struct dm_rq_target_io
*tio
= clone
->end_io_data
;
1157 struct mapped_device
*md
= tio
->md
;
1158 struct request
*rq
= tio
->orig
;
1160 if (rq
->cmd_type
== REQ_TYPE_BLOCK_PC
) {
1161 rq
->errors
= clone
->errors
;
1162 rq
->resid_len
= clone
->resid_len
;
1166 * We are using the sense buffer of the original
1168 * So setting the length of the sense data is enough.
1170 rq
->sense_len
= clone
->sense_len
;
1173 free_rq_clone(clone
);
1174 rq_end_stats(md
, rq
);
1176 blk_end_request_all(rq
, error
);
1178 blk_mq_end_request(rq
, error
);
1179 rq_completed(md
, rw
, true);
1182 static void dm_unprep_request(struct request
*rq
)
1184 struct dm_rq_target_io
*tio
= tio_from_request(rq
);
1185 struct request
*clone
= tio
->clone
;
1187 if (!rq
->q
->mq_ops
) {
1189 rq
->cmd_flags
&= ~REQ_DONTPREP
;
1193 free_rq_clone(clone
);
1194 else if (!tio
->md
->queue
->mq_ops
)
1199 * Requeue the original request of a clone.
1201 static void old_requeue_request(struct request
*rq
)
1203 struct request_queue
*q
= rq
->q
;
1204 unsigned long flags
;
1206 spin_lock_irqsave(q
->queue_lock
, flags
);
1207 blk_requeue_request(q
, rq
);
1208 blk_run_queue_async(q
);
1209 spin_unlock_irqrestore(q
->queue_lock
, flags
);
1212 static void dm_requeue_original_request(struct mapped_device
*md
,
1215 int rw
= rq_data_dir(rq
);
1217 dm_unprep_request(rq
);
1219 rq_end_stats(md
, rq
);
1221 old_requeue_request(rq
);
1223 blk_mq_requeue_request(rq
);
1224 blk_mq_kick_requeue_list(rq
->q
);
1227 rq_completed(md
, rw
, false);
1230 static void old_stop_queue(struct request_queue
*q
)
1232 unsigned long flags
;
1234 if (blk_queue_stopped(q
))
1237 spin_lock_irqsave(q
->queue_lock
, flags
);
1239 spin_unlock_irqrestore(q
->queue_lock
, flags
);
1242 static void stop_queue(struct request_queue
*q
)
1247 blk_mq_stop_hw_queues(q
);
1250 static void old_start_queue(struct request_queue
*q
)
1252 unsigned long flags
;
1254 spin_lock_irqsave(q
->queue_lock
, flags
);
1255 if (blk_queue_stopped(q
))
1257 spin_unlock_irqrestore(q
->queue_lock
, flags
);
1260 static void start_queue(struct request_queue
*q
)
1265 blk_mq_start_stopped_hw_queues(q
, true);
1268 static void dm_done(struct request
*clone
, int error
, bool mapped
)
1271 struct dm_rq_target_io
*tio
= clone
->end_io_data
;
1272 dm_request_endio_fn rq_end_io
= NULL
;
1275 rq_end_io
= tio
->ti
->type
->rq_end_io
;
1277 if (mapped
&& rq_end_io
)
1278 r
= rq_end_io(tio
->ti
, clone
, error
, &tio
->info
);
1281 if (unlikely(r
== -EREMOTEIO
&& (clone
->cmd_flags
& REQ_WRITE_SAME
) &&
1282 !clone
->q
->limits
.max_write_same_sectors
))
1283 disable_write_same(tio
->md
);
1286 /* The target wants to complete the I/O */
1287 dm_end_request(clone
, r
);
1288 else if (r
== DM_ENDIO_INCOMPLETE
)
1289 /* The target will handle the I/O */
1291 else if (r
== DM_ENDIO_REQUEUE
)
1292 /* The target wants to requeue the I/O */
1293 dm_requeue_original_request(tio
->md
, tio
->orig
);
1295 DMWARN("unimplemented target endio return value: %d", r
);
1301 * Request completion handler for request-based dm
1303 static void dm_softirq_done(struct request
*rq
)
1306 struct dm_rq_target_io
*tio
= tio_from_request(rq
);
1307 struct request
*clone
= tio
->clone
;
1311 rq_end_stats(tio
->md
, rq
);
1312 rw
= rq_data_dir(rq
);
1313 if (!rq
->q
->mq_ops
) {
1314 blk_end_request_all(rq
, tio
->error
);
1315 rq_completed(tio
->md
, rw
, false);
1318 blk_mq_end_request(rq
, tio
->error
);
1319 rq_completed(tio
->md
, rw
, false);
1324 if (rq
->cmd_flags
& REQ_FAILED
)
1327 dm_done(clone
, tio
->error
, mapped
);
1331 * Complete the clone and the original request with the error status
1332 * through softirq context.
1334 static void dm_complete_request(struct request
*rq
, int error
)
1336 struct dm_rq_target_io
*tio
= tio_from_request(rq
);
1339 blk_complete_request(rq
);
1343 * Complete the not-mapped clone and the original request with the error status
1344 * through softirq context.
1345 * Target's rq_end_io() function isn't called.
1346 * This may be used when the target's map_rq() or clone_and_map_rq() functions fail.
1348 static void dm_kill_unmapped_request(struct request
*rq
, int error
)
1350 rq
->cmd_flags
|= REQ_FAILED
;
1351 dm_complete_request(rq
, error
);
1355 * Called with the clone's queue lock held (for non-blk-mq)
1357 static void end_clone_request(struct request
*clone
, int error
)
1359 struct dm_rq_target_io
*tio
= clone
->end_io_data
;
1361 if (!clone
->q
->mq_ops
) {
1363 * For just cleaning up the information of the queue in which
1364 * the clone was dispatched.
1365 * The clone is *NOT* freed actually here because it is alloced
1366 * from dm own mempool (REQ_ALLOCED isn't set).
1368 __blk_put_request(clone
->q
, clone
);
1372 * Actual request completion is done in a softirq context which doesn't
1373 * hold the clone's queue lock. Otherwise, deadlock could occur because:
1374 * - another request may be submitted by the upper level driver
1375 * of the stacking during the completion
1376 * - the submission which requires queue lock may be done
1377 * against this clone's queue
1379 dm_complete_request(tio
->orig
, error
);
1383 * Return maximum size of I/O possible at the supplied sector up to the current
1386 static sector_t
max_io_len_target_boundary(sector_t sector
, struct dm_target
*ti
)
1388 sector_t target_offset
= dm_target_offset(ti
, sector
);
1390 return ti
->len
- target_offset
;
1393 static sector_t
max_io_len(sector_t sector
, struct dm_target
*ti
)
1395 sector_t len
= max_io_len_target_boundary(sector
, ti
);
1396 sector_t offset
, max_len
;
1399 * Does the target need to split even further?
1401 if (ti
->max_io_len
) {
1402 offset
= dm_target_offset(ti
, sector
);
1403 if (unlikely(ti
->max_io_len
& (ti
->max_io_len
- 1)))
1404 max_len
= sector_div(offset
, ti
->max_io_len
);
1406 max_len
= offset
& (ti
->max_io_len
- 1);
1407 max_len
= ti
->max_io_len
- max_len
;
1416 int dm_set_target_max_io_len(struct dm_target
*ti
, sector_t len
)
1418 if (len
> UINT_MAX
) {
1419 DMERR("Specified maximum size of target IO (%llu) exceeds limit (%u)",
1420 (unsigned long long)len
, UINT_MAX
);
1421 ti
->error
= "Maximum size of target IO is too large";
1425 ti
->max_io_len
= (uint32_t) len
;
1429 EXPORT_SYMBOL_GPL(dm_set_target_max_io_len
);
1432 * A target may call dm_accept_partial_bio only from the map routine. It is
1433 * allowed for all bio types except REQ_FLUSH.
1435 * dm_accept_partial_bio informs the dm that the target only wants to process
1436 * additional n_sectors sectors of the bio and the rest of the data should be
1437 * sent in a next bio.
1439 * A diagram that explains the arithmetics:
1440 * +--------------------+---------------+-------+
1442 * +--------------------+---------------+-------+
1444 * <-------------- *tio->len_ptr --------------->
1445 * <------- bi_size ------->
1448 * Region 1 was already iterated over with bio_advance or similar function.
1449 * (it may be empty if the target doesn't use bio_advance)
1450 * Region 2 is the remaining bio size that the target wants to process.
1451 * (it may be empty if region 1 is non-empty, although there is no reason
1453 * The target requires that region 3 is to be sent in the next bio.
1455 * If the target wants to receive multiple copies of the bio (via num_*bios, etc),
1456 * the partially processed part (the sum of regions 1+2) must be the same for all
1457 * copies of the bio.
1459 void dm_accept_partial_bio(struct bio
*bio
, unsigned n_sectors
)
1461 struct dm_target_io
*tio
= container_of(bio
, struct dm_target_io
, clone
);
1462 unsigned bi_size
= bio
->bi_iter
.bi_size
>> SECTOR_SHIFT
;
1463 BUG_ON(bio
->bi_rw
& REQ_FLUSH
);
1464 BUG_ON(bi_size
> *tio
->len_ptr
);
1465 BUG_ON(n_sectors
> bi_size
);
1466 *tio
->len_ptr
-= bi_size
- n_sectors
;
1467 bio
->bi_iter
.bi_size
= n_sectors
<< SECTOR_SHIFT
;
1469 EXPORT_SYMBOL_GPL(dm_accept_partial_bio
);
1471 static void __map_bio(struct dm_target_io
*tio
)
1475 struct mapped_device
*md
;
1476 struct bio
*clone
= &tio
->clone
;
1477 struct dm_target
*ti
= tio
->ti
;
1479 clone
->bi_end_io
= clone_endio
;
1482 * Map the clone. If r == 0 we don't need to do
1483 * anything, the target has assumed ownership of
1486 atomic_inc(&tio
->io
->io_count
);
1487 sector
= clone
->bi_iter
.bi_sector
;
1488 r
= ti
->type
->map(ti
, clone
);
1489 if (r
== DM_MAPIO_REMAPPED
) {
1490 /* the bio has been remapped so dispatch it */
1492 trace_block_bio_remap(bdev_get_queue(clone
->bi_bdev
), clone
,
1493 tio
->io
->bio
->bi_bdev
->bd_dev
, sector
);
1495 generic_make_request(clone
);
1496 } else if (r
< 0 || r
== DM_MAPIO_REQUEUE
) {
1497 /* error the io and bail out, or requeue it if needed */
1499 dec_pending(tio
->io
, r
);
1501 } else if (r
!= DM_MAPIO_SUBMITTED
) {
1502 DMWARN("unimplemented target map return value: %d", r
);
1508 struct mapped_device
*md
;
1509 struct dm_table
*map
;
1513 unsigned sector_count
;
1516 static void bio_setup_sector(struct bio
*bio
, sector_t sector
, unsigned len
)
1518 bio
->bi_iter
.bi_sector
= sector
;
1519 bio
->bi_iter
.bi_size
= to_bytes(len
);
1523 * Creates a bio that consists of range of complete bvecs.
1525 static void clone_bio(struct dm_target_io
*tio
, struct bio
*bio
,
1526 sector_t sector
, unsigned len
)
1528 struct bio
*clone
= &tio
->clone
;
1530 __bio_clone_fast(clone
, bio
);
1532 if (bio_integrity(bio
))
1533 bio_integrity_clone(clone
, bio
, GFP_NOIO
);
1535 bio_advance(clone
, to_bytes(sector
- clone
->bi_iter
.bi_sector
));
1536 clone
->bi_iter
.bi_size
= to_bytes(len
);
1538 if (bio_integrity(bio
))
1539 bio_integrity_trim(clone
, 0, len
);
1542 static struct dm_target_io
*alloc_tio(struct clone_info
*ci
,
1543 struct dm_target
*ti
,
1544 unsigned target_bio_nr
)
1546 struct dm_target_io
*tio
;
1549 clone
= bio_alloc_bioset(GFP_NOIO
, 0, ci
->md
->bs
);
1550 tio
= container_of(clone
, struct dm_target_io
, clone
);
1554 tio
->target_bio_nr
= target_bio_nr
;
1559 static void __clone_and_map_simple_bio(struct clone_info
*ci
,
1560 struct dm_target
*ti
,
1561 unsigned target_bio_nr
, unsigned *len
)
1563 struct dm_target_io
*tio
= alloc_tio(ci
, ti
, target_bio_nr
);
1564 struct bio
*clone
= &tio
->clone
;
1568 __bio_clone_fast(clone
, ci
->bio
);
1570 bio_setup_sector(clone
, ci
->sector
, *len
);
1575 static void __send_duplicate_bios(struct clone_info
*ci
, struct dm_target
*ti
,
1576 unsigned num_bios
, unsigned *len
)
1578 unsigned target_bio_nr
;
1580 for (target_bio_nr
= 0; target_bio_nr
< num_bios
; target_bio_nr
++)
1581 __clone_and_map_simple_bio(ci
, ti
, target_bio_nr
, len
);
1584 static int __send_empty_flush(struct clone_info
*ci
)
1586 unsigned target_nr
= 0;
1587 struct dm_target
*ti
;
1589 BUG_ON(bio_has_data(ci
->bio
));
1590 while ((ti
= dm_table_get_target(ci
->map
, target_nr
++)))
1591 __send_duplicate_bios(ci
, ti
, ti
->num_flush_bios
, NULL
);
1596 static void __clone_and_map_data_bio(struct clone_info
*ci
, struct dm_target
*ti
,
1597 sector_t sector
, unsigned *len
)
1599 struct bio
*bio
= ci
->bio
;
1600 struct dm_target_io
*tio
;
1601 unsigned target_bio_nr
;
1602 unsigned num_target_bios
= 1;
1605 * Does the target want to receive duplicate copies of the bio?
1607 if (bio_data_dir(bio
) == WRITE
&& ti
->num_write_bios
)
1608 num_target_bios
= ti
->num_write_bios(ti
, bio
);
1610 for (target_bio_nr
= 0; target_bio_nr
< num_target_bios
; target_bio_nr
++) {
1611 tio
= alloc_tio(ci
, ti
, target_bio_nr
);
1613 clone_bio(tio
, bio
, sector
, *len
);
1618 typedef unsigned (*get_num_bios_fn
)(struct dm_target
*ti
);
1620 static unsigned get_num_discard_bios(struct dm_target
*ti
)
1622 return ti
->num_discard_bios
;
1625 static unsigned get_num_write_same_bios(struct dm_target
*ti
)
1627 return ti
->num_write_same_bios
;
1630 typedef bool (*is_split_required_fn
)(struct dm_target
*ti
);
1632 static bool is_split_required_for_discard(struct dm_target
*ti
)
1634 return ti
->split_discard_bios
;
1637 static int __send_changing_extent_only(struct clone_info
*ci
,
1638 get_num_bios_fn get_num_bios
,
1639 is_split_required_fn is_split_required
)
1641 struct dm_target
*ti
;
1646 ti
= dm_table_find_target(ci
->map
, ci
->sector
);
1647 if (!dm_target_is_valid(ti
))
1651 * Even though the device advertised support for this type of
1652 * request, that does not mean every target supports it, and
1653 * reconfiguration might also have changed that since the
1654 * check was performed.
1656 num_bios
= get_num_bios
? get_num_bios(ti
) : 0;
1660 if (is_split_required
&& !is_split_required(ti
))
1661 len
= min((sector_t
)ci
->sector_count
, max_io_len_target_boundary(ci
->sector
, ti
));
1663 len
= min((sector_t
)ci
->sector_count
, max_io_len(ci
->sector
, ti
));
1665 __send_duplicate_bios(ci
, ti
, num_bios
, &len
);
1668 } while (ci
->sector_count
-= len
);
1673 static int __send_discard(struct clone_info
*ci
)
1675 return __send_changing_extent_only(ci
, get_num_discard_bios
,
1676 is_split_required_for_discard
);
1679 static int __send_write_same(struct clone_info
*ci
)
1681 return __send_changing_extent_only(ci
, get_num_write_same_bios
, NULL
);
1685 * Select the correct strategy for processing a non-flush bio.
1687 static int __split_and_process_non_flush(struct clone_info
*ci
)
1689 struct bio
*bio
= ci
->bio
;
1690 struct dm_target
*ti
;
1693 if (unlikely(bio
->bi_rw
& REQ_DISCARD
))
1694 return __send_discard(ci
);
1695 else if (unlikely(bio
->bi_rw
& REQ_WRITE_SAME
))
1696 return __send_write_same(ci
);
1698 ti
= dm_table_find_target(ci
->map
, ci
->sector
);
1699 if (!dm_target_is_valid(ti
))
1702 len
= min_t(sector_t
, max_io_len(ci
->sector
, ti
), ci
->sector_count
);
1704 __clone_and_map_data_bio(ci
, ti
, ci
->sector
, &len
);
1707 ci
->sector_count
-= len
;
1713 * Entry point to split a bio into clones and submit them to the targets.
1715 static void __split_and_process_bio(struct mapped_device
*md
,
1716 struct dm_table
*map
, struct bio
*bio
)
1718 struct clone_info ci
;
1721 if (unlikely(!map
)) {
1728 ci
.io
= alloc_io(md
);
1730 atomic_set(&ci
.io
->io_count
, 1);
1733 spin_lock_init(&ci
.io
->endio_lock
);
1734 ci
.sector
= bio
->bi_iter
.bi_sector
;
1736 start_io_acct(ci
.io
);
1738 if (bio
->bi_rw
& REQ_FLUSH
) {
1739 ci
.bio
= &ci
.md
->flush_bio
;
1740 ci
.sector_count
= 0;
1741 error
= __send_empty_flush(&ci
);
1742 /* dec_pending submits any data associated with flush */
1745 ci
.sector_count
= bio_sectors(bio
);
1746 while (ci
.sector_count
&& !error
)
1747 error
= __split_and_process_non_flush(&ci
);
1750 /* drop the extra reference count */
1751 dec_pending(ci
.io
, error
);
1753 /*-----------------------------------------------------------------
1755 *---------------------------------------------------------------*/
1758 * The request function that just remaps the bio built up by
1761 static blk_qc_t
dm_make_request(struct request_queue
*q
, struct bio
*bio
)
1763 int rw
= bio_data_dir(bio
);
1764 struct mapped_device
*md
= q
->queuedata
;
1766 struct dm_table
*map
;
1768 map
= dm_get_live_table(md
, &srcu_idx
);
1770 generic_start_io_acct(rw
, bio_sectors(bio
), &dm_disk(md
)->part0
);
1772 /* if we're suspended, we have to queue this io for later */
1773 if (unlikely(test_bit(DMF_BLOCK_IO_FOR_SUSPEND
, &md
->flags
))) {
1774 dm_put_live_table(md
, srcu_idx
);
1776 if (bio_rw(bio
) != READA
)
1780 return BLK_QC_T_NONE
;
1783 __split_and_process_bio(md
, map
, bio
);
1784 dm_put_live_table(md
, srcu_idx
);
1785 return BLK_QC_T_NONE
;
1788 int dm_request_based(struct mapped_device
*md
)
1790 return blk_queue_stackable(md
->queue
);
1793 static void dm_dispatch_clone_request(struct request
*clone
, struct request
*rq
)
1797 if (blk_queue_io_stat(clone
->q
))
1798 clone
->cmd_flags
|= REQ_IO_STAT
;
1800 clone
->start_time
= jiffies
;
1801 r
= blk_insert_cloned_request(clone
->q
, clone
);
1803 /* must complete clone in terms of original request */
1804 dm_complete_request(rq
, r
);
1807 static int dm_rq_bio_constructor(struct bio
*bio
, struct bio
*bio_orig
,
1810 struct dm_rq_target_io
*tio
= data
;
1811 struct dm_rq_clone_bio_info
*info
=
1812 container_of(bio
, struct dm_rq_clone_bio_info
, clone
);
1814 info
->orig
= bio_orig
;
1816 bio
->bi_end_io
= end_clone_bio
;
1821 static int setup_clone(struct request
*clone
, struct request
*rq
,
1822 struct dm_rq_target_io
*tio
, gfp_t gfp_mask
)
1826 r
= blk_rq_prep_clone(clone
, rq
, tio
->md
->bs
, gfp_mask
,
1827 dm_rq_bio_constructor
, tio
);
1831 clone
->cmd
= rq
->cmd
;
1832 clone
->cmd_len
= rq
->cmd_len
;
1833 clone
->sense
= rq
->sense
;
1834 clone
->end_io
= end_clone_request
;
1835 clone
->end_io_data
= tio
;
1842 static struct request
*clone_rq(struct request
*rq
, struct mapped_device
*md
,
1843 struct dm_rq_target_io
*tio
, gfp_t gfp_mask
)
1846 * Do not allocate a clone if tio->clone was already set
1847 * (see: dm_mq_queue_rq).
1849 bool alloc_clone
= !tio
->clone
;
1850 struct request
*clone
;
1853 clone
= alloc_clone_request(md
, gfp_mask
);
1859 blk_rq_init(NULL
, clone
);
1860 if (setup_clone(clone
, rq
, tio
, gfp_mask
)) {
1863 free_clone_request(md
, clone
);
1870 static void map_tio_request(struct kthread_work
*work
);
1872 static void init_tio(struct dm_rq_target_io
*tio
, struct request
*rq
,
1873 struct mapped_device
*md
)
1880 memset(&tio
->info
, 0, sizeof(tio
->info
));
1881 if (md
->kworker_task
)
1882 init_kthread_work(&tio
->work
, map_tio_request
);
1885 static struct dm_rq_target_io
*prep_tio(struct request
*rq
,
1886 struct mapped_device
*md
, gfp_t gfp_mask
)
1888 struct dm_rq_target_io
*tio
;
1890 struct dm_table
*table
;
1892 tio
= alloc_rq_tio(md
, gfp_mask
);
1896 init_tio(tio
, rq
, md
);
1898 table
= dm_get_live_table(md
, &srcu_idx
);
1899 if (!dm_table_mq_request_based(table
)) {
1900 if (!clone_rq(rq
, md
, tio
, gfp_mask
)) {
1901 dm_put_live_table(md
, srcu_idx
);
1906 dm_put_live_table(md
, srcu_idx
);
1912 * Called with the queue lock held.
1914 static int dm_prep_fn(struct request_queue
*q
, struct request
*rq
)
1916 struct mapped_device
*md
= q
->queuedata
;
1917 struct dm_rq_target_io
*tio
;
1919 if (unlikely(rq
->special
)) {
1920 DMWARN("Already has something in rq->special.");
1921 return BLKPREP_KILL
;
1924 tio
= prep_tio(rq
, md
, GFP_ATOMIC
);
1926 return BLKPREP_DEFER
;
1929 rq
->cmd_flags
|= REQ_DONTPREP
;
1936 * 0 : the request has been processed
1937 * DM_MAPIO_REQUEUE : the original request needs to be requeued
1938 * < 0 : the request was completed due to failure
1940 static int map_request(struct dm_rq_target_io
*tio
, struct request
*rq
,
1941 struct mapped_device
*md
)
1944 struct dm_target
*ti
= tio
->ti
;
1945 struct request
*clone
= NULL
;
1949 r
= ti
->type
->map_rq(ti
, clone
, &tio
->info
);
1951 r
= ti
->type
->clone_and_map_rq(ti
, rq
, &tio
->info
, &clone
);
1953 /* The target wants to complete the I/O */
1954 dm_kill_unmapped_request(rq
, r
);
1957 if (r
!= DM_MAPIO_REMAPPED
)
1959 if (setup_clone(clone
, rq
, tio
, GFP_ATOMIC
)) {
1961 ti
->type
->release_clone_rq(clone
);
1962 return DM_MAPIO_REQUEUE
;
1967 case DM_MAPIO_SUBMITTED
:
1968 /* The target has taken the I/O to submit by itself later */
1970 case DM_MAPIO_REMAPPED
:
1971 /* The target has remapped the I/O so dispatch it */
1972 trace_block_rq_remap(clone
->q
, clone
, disk_devt(dm_disk(md
)),
1974 dm_dispatch_clone_request(clone
, rq
);
1976 case DM_MAPIO_REQUEUE
:
1977 /* The target wants to requeue the I/O */
1978 dm_requeue_original_request(md
, tio
->orig
);
1982 DMWARN("unimplemented target map return value: %d", r
);
1986 /* The target wants to complete the I/O */
1987 dm_kill_unmapped_request(rq
, r
);
1994 static void map_tio_request(struct kthread_work
*work
)
1996 struct dm_rq_target_io
*tio
= container_of(work
, struct dm_rq_target_io
, work
);
1997 struct request
*rq
= tio
->orig
;
1998 struct mapped_device
*md
= tio
->md
;
2000 if (map_request(tio
, rq
, md
) == DM_MAPIO_REQUEUE
)
2001 dm_requeue_original_request(md
, rq
);
2004 static void dm_start_request(struct mapped_device
*md
, struct request
*orig
)
2006 if (!orig
->q
->mq_ops
)
2007 blk_start_request(orig
);
2009 blk_mq_start_request(orig
);
2010 atomic_inc(&md
->pending
[rq_data_dir(orig
)]);
2012 if (md
->seq_rq_merge_deadline_usecs
) {
2013 md
->last_rq_pos
= rq_end_sector(orig
);
2014 md
->last_rq_rw
= rq_data_dir(orig
);
2015 md
->last_rq_start_time
= ktime_get();
2018 if (unlikely(dm_stats_used(&md
->stats
))) {
2019 struct dm_rq_target_io
*tio
= tio_from_request(orig
);
2020 tio
->duration_jiffies
= jiffies
;
2021 tio
->n_sectors
= blk_rq_sectors(orig
);
2022 dm_stats_account_io(&md
->stats
, orig
->cmd_flags
, blk_rq_pos(orig
),
2023 tio
->n_sectors
, false, 0, &tio
->stats_aux
);
2027 * Hold the md reference here for the in-flight I/O.
2028 * We can't rely on the reference count by device opener,
2029 * because the device may be closed during the request completion
2030 * when all bios are completed.
2031 * See the comment in rq_completed() too.
2036 #define MAX_SEQ_RQ_MERGE_DEADLINE_USECS 100000
2038 ssize_t
dm_attr_rq_based_seq_io_merge_deadline_show(struct mapped_device
*md
, char *buf
)
2040 return sprintf(buf
, "%u\n", md
->seq_rq_merge_deadline_usecs
);
2043 ssize_t
dm_attr_rq_based_seq_io_merge_deadline_store(struct mapped_device
*md
,
2044 const char *buf
, size_t count
)
2048 if (!dm_request_based(md
) || md
->use_blk_mq
)
2051 if (kstrtouint(buf
, 10, &deadline
))
2054 if (deadline
> MAX_SEQ_RQ_MERGE_DEADLINE_USECS
)
2055 deadline
= MAX_SEQ_RQ_MERGE_DEADLINE_USECS
;
2057 md
->seq_rq_merge_deadline_usecs
= deadline
;
2062 static bool dm_request_peeked_before_merge_deadline(struct mapped_device
*md
)
2064 ktime_t kt_deadline
;
2066 if (!md
->seq_rq_merge_deadline_usecs
)
2069 kt_deadline
= ns_to_ktime((u64
)md
->seq_rq_merge_deadline_usecs
* NSEC_PER_USEC
);
2070 kt_deadline
= ktime_add_safe(md
->last_rq_start_time
, kt_deadline
);
2072 return !ktime_after(ktime_get(), kt_deadline
);
2076 * q->request_fn for request-based dm.
2077 * Called with the queue lock held.
2079 static void dm_request_fn(struct request_queue
*q
)
2081 struct mapped_device
*md
= q
->queuedata
;
2083 struct dm_table
*map
= dm_get_live_table(md
, &srcu_idx
);
2084 struct dm_target
*ti
;
2086 struct dm_rq_target_io
*tio
;
2090 * For suspend, check blk_queue_stopped() and increment
2091 * ->pending within a single queue_lock not to increment the
2092 * number of in-flight I/Os after the queue is stopped in
2095 while (!blk_queue_stopped(q
)) {
2096 rq
= blk_peek_request(q
);
2100 /* always use block 0 to find the target for flushes for now */
2102 if (!(rq
->cmd_flags
& REQ_FLUSH
))
2103 pos
= blk_rq_pos(rq
);
2105 ti
= dm_table_find_target(map
, pos
);
2106 if (!dm_target_is_valid(ti
)) {
2108 * Must perform setup, that rq_completed() requires,
2109 * before calling dm_kill_unmapped_request
2111 DMERR_LIMIT("request attempted access beyond the end of device");
2112 dm_start_request(md
, rq
);
2113 dm_kill_unmapped_request(rq
, -EIO
);
2117 if (dm_request_peeked_before_merge_deadline(md
) &&
2118 md_in_flight(md
) && rq
->bio
&& rq
->bio
->bi_vcnt
== 1 &&
2119 md
->last_rq_pos
== pos
&& md
->last_rq_rw
== rq_data_dir(rq
))
2122 if (ti
->type
->busy
&& ti
->type
->busy(ti
))
2125 dm_start_request(md
, rq
);
2127 tio
= tio_from_request(rq
);
2128 /* Establish tio->ti before queuing work (map_tio_request) */
2130 queue_kthread_work(&md
->kworker
, &tio
->work
);
2131 BUG_ON(!irqs_disabled());
2137 blk_delay_queue(q
, HZ
/ 100);
2139 dm_put_live_table(md
, srcu_idx
);
2142 static int dm_any_congested(void *congested_data
, int bdi_bits
)
2145 struct mapped_device
*md
= congested_data
;
2146 struct dm_table
*map
;
2148 if (!test_bit(DMF_BLOCK_IO_FOR_SUSPEND
, &md
->flags
)) {
2149 map
= dm_get_live_table_fast(md
);
2152 * Request-based dm cares about only own queue for
2153 * the query about congestion status of request_queue
2155 if (dm_request_based(md
))
2156 r
= md
->queue
->backing_dev_info
.wb
.state
&
2159 r
= dm_table_any_congested(map
, bdi_bits
);
2161 dm_put_live_table_fast(md
);
2167 /*-----------------------------------------------------------------
2168 * An IDR is used to keep track of allocated minor numbers.
2169 *---------------------------------------------------------------*/
2170 static void free_minor(int minor
)
2172 spin_lock(&_minor_lock
);
2173 idr_remove(&_minor_idr
, minor
);
2174 spin_unlock(&_minor_lock
);
2178 * See if the device with a specific minor # is free.
2180 static int specific_minor(int minor
)
2184 if (minor
>= (1 << MINORBITS
))
2187 idr_preload(GFP_KERNEL
);
2188 spin_lock(&_minor_lock
);
2190 r
= idr_alloc(&_minor_idr
, MINOR_ALLOCED
, minor
, minor
+ 1, GFP_NOWAIT
);
2192 spin_unlock(&_minor_lock
);
2195 return r
== -ENOSPC
? -EBUSY
: r
;
2199 static int next_free_minor(int *minor
)
2203 idr_preload(GFP_KERNEL
);
2204 spin_lock(&_minor_lock
);
2206 r
= idr_alloc(&_minor_idr
, MINOR_ALLOCED
, 0, 1 << MINORBITS
, GFP_NOWAIT
);
2208 spin_unlock(&_minor_lock
);
2216 static const struct block_device_operations dm_blk_dops
;
2218 static void dm_wq_work(struct work_struct
*work
);
2220 static void dm_init_md_queue(struct mapped_device
*md
)
2223 * Request-based dm devices cannot be stacked on top of bio-based dm
2224 * devices. The type of this dm device may not have been decided yet.
2225 * The type is decided at the first table loading time.
2226 * To prevent problematic device stacking, clear the queue flag
2227 * for request stacking support until then.
2229 * This queue is new, so no concurrency on the queue_flags.
2231 queue_flag_clear_unlocked(QUEUE_FLAG_STACKABLE
, md
->queue
);
2234 * Initialize data that will only be used by a non-blk-mq DM queue
2235 * - must do so here (in alloc_dev callchain) before queue is used
2237 md
->queue
->queuedata
= md
;
2238 md
->queue
->backing_dev_info
.congested_data
= md
;
2241 static void dm_init_old_md_queue(struct mapped_device
*md
)
2243 md
->use_blk_mq
= false;
2244 dm_init_md_queue(md
);
2247 * Initialize aspects of queue that aren't relevant for blk-mq
2249 md
->queue
->backing_dev_info
.congested_fn
= dm_any_congested
;
2250 blk_queue_bounce_limit(md
->queue
, BLK_BOUNCE_ANY
);
2253 static void cleanup_mapped_device(struct mapped_device
*md
)
2256 destroy_workqueue(md
->wq
);
2257 if (md
->kworker_task
)
2258 kthread_stop(md
->kworker_task
);
2259 mempool_destroy(md
->io_pool
);
2260 mempool_destroy(md
->rq_pool
);
2262 bioset_free(md
->bs
);
2264 cleanup_srcu_struct(&md
->io_barrier
);
2267 spin_lock(&_minor_lock
);
2268 md
->disk
->private_data
= NULL
;
2269 spin_unlock(&_minor_lock
);
2270 del_gendisk(md
->disk
);
2275 blk_cleanup_queue(md
->queue
);
2284 * Allocate and initialise a blank device with a given minor.
2286 static struct mapped_device
*alloc_dev(int minor
)
2289 struct mapped_device
*md
= kzalloc(sizeof(*md
), GFP_KERNEL
);
2293 DMWARN("unable to allocate device, out of memory.");
2297 if (!try_module_get(THIS_MODULE
))
2298 goto bad_module_get
;
2300 /* get a minor number for the dev */
2301 if (minor
== DM_ANY_MINOR
)
2302 r
= next_free_minor(&minor
);
2304 r
= specific_minor(minor
);
2308 r
= init_srcu_struct(&md
->io_barrier
);
2310 goto bad_io_barrier
;
2312 md
->use_blk_mq
= use_blk_mq
;
2313 md
->type
= DM_TYPE_NONE
;
2314 mutex_init(&md
->suspend_lock
);
2315 mutex_init(&md
->type_lock
);
2316 mutex_init(&md
->table_devices_lock
);
2317 spin_lock_init(&md
->deferred_lock
);
2318 atomic_set(&md
->holders
, 1);
2319 atomic_set(&md
->open_count
, 0);
2320 atomic_set(&md
->event_nr
, 0);
2321 atomic_set(&md
->uevent_seq
, 0);
2322 INIT_LIST_HEAD(&md
->uevent_list
);
2323 INIT_LIST_HEAD(&md
->table_devices
);
2324 spin_lock_init(&md
->uevent_lock
);
2326 md
->queue
= blk_alloc_queue(GFP_KERNEL
);
2330 dm_init_md_queue(md
);
2332 md
->disk
= alloc_disk(1);
2336 atomic_set(&md
->pending
[0], 0);
2337 atomic_set(&md
->pending
[1], 0);
2338 init_waitqueue_head(&md
->wait
);
2339 INIT_WORK(&md
->work
, dm_wq_work
);
2340 init_waitqueue_head(&md
->eventq
);
2341 init_completion(&md
->kobj_holder
.completion
);
2342 md
->kworker_task
= NULL
;
2344 md
->disk
->major
= _major
;
2345 md
->disk
->first_minor
= minor
;
2346 md
->disk
->fops
= &dm_blk_dops
;
2347 md
->disk
->queue
= md
->queue
;
2348 md
->disk
->private_data
= md
;
2349 sprintf(md
->disk
->disk_name
, "dm-%d", minor
);
2351 format_dev_t(md
->name
, MKDEV(_major
, minor
));
2353 md
->wq
= alloc_workqueue("kdmflush", WQ_MEM_RECLAIM
, 0);
2357 md
->bdev
= bdget_disk(md
->disk
, 0);
2361 bio_init(&md
->flush_bio
);
2362 md
->flush_bio
.bi_bdev
= md
->bdev
;
2363 md
->flush_bio
.bi_rw
= WRITE_FLUSH
;
2365 dm_stats_init(&md
->stats
);
2367 /* Populate the mapping, nobody knows we exist yet */
2368 spin_lock(&_minor_lock
);
2369 old_md
= idr_replace(&_minor_idr
, md
, minor
);
2370 spin_unlock(&_minor_lock
);
2372 BUG_ON(old_md
!= MINOR_ALLOCED
);
2377 cleanup_mapped_device(md
);
2381 module_put(THIS_MODULE
);
2387 static void unlock_fs(struct mapped_device
*md
);
2389 static void free_dev(struct mapped_device
*md
)
2391 int minor
= MINOR(disk_devt(md
->disk
));
2395 cleanup_mapped_device(md
);
2397 blk_mq_free_tag_set(&md
->tag_set
);
2399 free_table_devices(&md
->table_devices
);
2400 dm_stats_cleanup(&md
->stats
);
2403 module_put(THIS_MODULE
);
2407 static void __bind_mempools(struct mapped_device
*md
, struct dm_table
*t
)
2409 struct dm_md_mempools
*p
= dm_table_get_md_mempools(t
);
2412 /* The md already has necessary mempools. */
2413 if (dm_table_get_type(t
) == DM_TYPE_BIO_BASED
) {
2415 * Reload bioset because front_pad may have changed
2416 * because a different table was loaded.
2418 bioset_free(md
->bs
);
2423 * There's no need to reload with request-based dm
2424 * because the size of front_pad doesn't change.
2425 * Note for future: If you are to reload bioset,
2426 * prep-ed requests in the queue may refer
2427 * to bio from the old bioset, so you must walk
2428 * through the queue to unprep.
2433 BUG_ON(!p
|| md
->io_pool
|| md
->rq_pool
|| md
->bs
);
2435 md
->io_pool
= p
->io_pool
;
2437 md
->rq_pool
= p
->rq_pool
;
2443 /* mempool bind completed, no longer need any mempools in the table */
2444 dm_table_free_md_mempools(t
);
2448 * Bind a table to the device.
2450 static void event_callback(void *context
)
2452 unsigned long flags
;
2454 struct mapped_device
*md
= (struct mapped_device
*) context
;
2456 spin_lock_irqsave(&md
->uevent_lock
, flags
);
2457 list_splice_init(&md
->uevent_list
, &uevents
);
2458 spin_unlock_irqrestore(&md
->uevent_lock
, flags
);
2460 dm_send_uevents(&uevents
, &disk_to_dev(md
->disk
)->kobj
);
2462 atomic_inc(&md
->event_nr
);
2463 wake_up(&md
->eventq
);
2467 * Protected by md->suspend_lock obtained by dm_swap_table().
2469 static void __set_size(struct mapped_device
*md
, sector_t size
)
2471 set_capacity(md
->disk
, size
);
2473 i_size_write(md
->bdev
->bd_inode
, (loff_t
)size
<< SECTOR_SHIFT
);
2477 * Returns old map, which caller must destroy.
2479 static struct dm_table
*__bind(struct mapped_device
*md
, struct dm_table
*t
,
2480 struct queue_limits
*limits
)
2482 struct dm_table
*old_map
;
2483 struct request_queue
*q
= md
->queue
;
2486 size
= dm_table_get_size(t
);
2489 * Wipe any geometry if the size of the table changed.
2491 if (size
!= dm_get_size(md
))
2492 memset(&md
->geometry
, 0, sizeof(md
->geometry
));
2494 __set_size(md
, size
);
2496 dm_table_event_callback(t
, event_callback
, md
);
2499 * The queue hasn't been stopped yet, if the old table type wasn't
2500 * for request-based during suspension. So stop it to prevent
2501 * I/O mapping before resume.
2502 * This must be done before setting the queue restrictions,
2503 * because request-based dm may be run just after the setting.
2505 if (dm_table_request_based(t
))
2508 __bind_mempools(md
, t
);
2510 old_map
= rcu_dereference_protected(md
->map
, lockdep_is_held(&md
->suspend_lock
));
2511 rcu_assign_pointer(md
->map
, t
);
2512 md
->immutable_target_type
= dm_table_get_immutable_target_type(t
);
2514 dm_table_set_restrictions(t
, q
, limits
);
2522 * Returns unbound table for the caller to free.
2524 static struct dm_table
*__unbind(struct mapped_device
*md
)
2526 struct dm_table
*map
= rcu_dereference_protected(md
->map
, 1);
2531 dm_table_event_callback(map
, NULL
, NULL
);
2532 RCU_INIT_POINTER(md
->map
, NULL
);
2539 * Constructor for a new device.
2541 int dm_create(int minor
, struct mapped_device
**result
)
2543 struct mapped_device
*md
;
2545 md
= alloc_dev(minor
);
2556 * Functions to manage md->type.
2557 * All are required to hold md->type_lock.
2559 void dm_lock_md_type(struct mapped_device
*md
)
2561 mutex_lock(&md
->type_lock
);
2564 void dm_unlock_md_type(struct mapped_device
*md
)
2566 mutex_unlock(&md
->type_lock
);
2569 void dm_set_md_type(struct mapped_device
*md
, unsigned type
)
2571 BUG_ON(!mutex_is_locked(&md
->type_lock
));
2575 unsigned dm_get_md_type(struct mapped_device
*md
)
2577 BUG_ON(!mutex_is_locked(&md
->type_lock
));
2581 struct target_type
*dm_get_immutable_target_type(struct mapped_device
*md
)
2583 return md
->immutable_target_type
;
2587 * The queue_limits are only valid as long as you have a reference
2590 struct queue_limits
*dm_get_queue_limits(struct mapped_device
*md
)
2592 BUG_ON(!atomic_read(&md
->holders
));
2593 return &md
->queue
->limits
;
2595 EXPORT_SYMBOL_GPL(dm_get_queue_limits
);
2597 static void init_rq_based_worker_thread(struct mapped_device
*md
)
2599 /* Initialize the request-based DM worker thread */
2600 init_kthread_worker(&md
->kworker
);
2601 md
->kworker_task
= kthread_run(kthread_worker_fn
, &md
->kworker
,
2602 "kdmwork-%s", dm_device_name(md
));
2606 * Fully initialize a request-based queue (->elevator, ->request_fn, etc).
2608 static int dm_init_request_based_queue(struct mapped_device
*md
)
2610 struct request_queue
*q
= NULL
;
2612 /* Fully initialize the queue */
2613 q
= blk_init_allocated_queue(md
->queue
, dm_request_fn
, NULL
);
2617 /* disable dm_request_fn's merge heuristic by default */
2618 md
->seq_rq_merge_deadline_usecs
= 0;
2621 dm_init_old_md_queue(md
);
2622 blk_queue_softirq_done(md
->queue
, dm_softirq_done
);
2623 blk_queue_prep_rq(md
->queue
, dm_prep_fn
);
2625 init_rq_based_worker_thread(md
);
2627 elv_register_queue(md
->queue
);
2632 static int dm_mq_init_request(void *data
, struct request
*rq
,
2633 unsigned int hctx_idx
, unsigned int request_idx
,
2634 unsigned int numa_node
)
2636 struct mapped_device
*md
= data
;
2637 struct dm_rq_target_io
*tio
= blk_mq_rq_to_pdu(rq
);
2640 * Must initialize md member of tio, otherwise it won't
2641 * be available in dm_mq_queue_rq.
2648 static int dm_mq_queue_rq(struct blk_mq_hw_ctx
*hctx
,
2649 const struct blk_mq_queue_data
*bd
)
2651 struct request
*rq
= bd
->rq
;
2652 struct dm_rq_target_io
*tio
= blk_mq_rq_to_pdu(rq
);
2653 struct mapped_device
*md
= tio
->md
;
2655 struct dm_table
*map
= dm_get_live_table(md
, &srcu_idx
);
2656 struct dm_target
*ti
;
2659 /* always use block 0 to find the target for flushes for now */
2661 if (!(rq
->cmd_flags
& REQ_FLUSH
))
2662 pos
= blk_rq_pos(rq
);
2664 ti
= dm_table_find_target(map
, pos
);
2665 if (!dm_target_is_valid(ti
)) {
2666 dm_put_live_table(md
, srcu_idx
);
2667 DMERR_LIMIT("request attempted access beyond the end of device");
2669 * Must perform setup, that rq_completed() requires,
2670 * before returning BLK_MQ_RQ_QUEUE_ERROR
2672 dm_start_request(md
, rq
);
2673 return BLK_MQ_RQ_QUEUE_ERROR
;
2675 dm_put_live_table(md
, srcu_idx
);
2677 if (ti
->type
->busy
&& ti
->type
->busy(ti
))
2678 return BLK_MQ_RQ_QUEUE_BUSY
;
2680 dm_start_request(md
, rq
);
2682 /* Init tio using md established in .init_request */
2683 init_tio(tio
, rq
, md
);
2686 * Establish tio->ti before queuing work (map_tio_request)
2687 * or making direct call to map_request().
2691 /* Clone the request if underlying devices aren't blk-mq */
2692 if (dm_table_get_type(map
) == DM_TYPE_REQUEST_BASED
) {
2693 /* clone request is allocated at the end of the pdu */
2694 tio
->clone
= (void *)blk_mq_rq_to_pdu(rq
) + sizeof(struct dm_rq_target_io
);
2695 (void) clone_rq(rq
, md
, tio
, GFP_ATOMIC
);
2696 queue_kthread_work(&md
->kworker
, &tio
->work
);
2698 /* Direct call is fine since .queue_rq allows allocations */
2699 if (map_request(tio
, rq
, md
) == DM_MAPIO_REQUEUE
) {
2700 /* Undo dm_start_request() before requeuing */
2701 rq_end_stats(md
, rq
);
2702 rq_completed(md
, rq_data_dir(rq
), false);
2703 return BLK_MQ_RQ_QUEUE_BUSY
;
2707 return BLK_MQ_RQ_QUEUE_OK
;
2710 static struct blk_mq_ops dm_mq_ops
= {
2711 .queue_rq
= dm_mq_queue_rq
,
2712 .map_queue
= blk_mq_map_queue
,
2713 .complete
= dm_softirq_done
,
2714 .init_request
= dm_mq_init_request
,
2717 static int dm_init_request_based_blk_mq_queue(struct mapped_device
*md
)
2719 unsigned md_type
= dm_get_md_type(md
);
2720 struct request_queue
*q
;
2723 memset(&md
->tag_set
, 0, sizeof(md
->tag_set
));
2724 md
->tag_set
.ops
= &dm_mq_ops
;
2725 md
->tag_set
.queue_depth
= BLKDEV_MAX_RQ
;
2726 md
->tag_set
.numa_node
= NUMA_NO_NODE
;
2727 md
->tag_set
.flags
= BLK_MQ_F_SHOULD_MERGE
| BLK_MQ_F_SG_MERGE
;
2728 md
->tag_set
.nr_hw_queues
= 1;
2729 if (md_type
== DM_TYPE_REQUEST_BASED
) {
2730 /* make the memory for non-blk-mq clone part of the pdu */
2731 md
->tag_set
.cmd_size
= sizeof(struct dm_rq_target_io
) + sizeof(struct request
);
2733 md
->tag_set
.cmd_size
= sizeof(struct dm_rq_target_io
);
2734 md
->tag_set
.driver_data
= md
;
2736 err
= blk_mq_alloc_tag_set(&md
->tag_set
);
2740 q
= blk_mq_init_allocated_queue(&md
->tag_set
, md
->queue
);
2746 dm_init_md_queue(md
);
2748 /* backfill 'mq' sysfs registration normally done in blk_register_queue */
2749 blk_mq_register_disk(md
->disk
);
2751 if (md_type
== DM_TYPE_REQUEST_BASED
)
2752 init_rq_based_worker_thread(md
);
2757 blk_mq_free_tag_set(&md
->tag_set
);
2761 static unsigned filter_md_type(unsigned type
, struct mapped_device
*md
)
2763 if (type
== DM_TYPE_BIO_BASED
)
2766 return !md
->use_blk_mq
? DM_TYPE_REQUEST_BASED
: DM_TYPE_MQ_REQUEST_BASED
;
2770 * Setup the DM device's queue based on md's type
2772 int dm_setup_md_queue(struct mapped_device
*md
)
2775 unsigned md_type
= filter_md_type(dm_get_md_type(md
), md
);
2778 case DM_TYPE_REQUEST_BASED
:
2779 r
= dm_init_request_based_queue(md
);
2781 DMWARN("Cannot initialize queue for request-based mapped device");
2785 case DM_TYPE_MQ_REQUEST_BASED
:
2786 r
= dm_init_request_based_blk_mq_queue(md
);
2788 DMWARN("Cannot initialize queue for request-based blk-mq mapped device");
2792 case DM_TYPE_BIO_BASED
:
2793 dm_init_old_md_queue(md
);
2794 blk_queue_make_request(md
->queue
, dm_make_request
);
2796 * DM handles splitting bios as needed. Free the bio_split bioset
2797 * since it won't be used (saves 1 process per bio-based DM device).
2799 bioset_free(md
->queue
->bio_split
);
2800 md
->queue
->bio_split
= NULL
;
2807 struct mapped_device
*dm_get_md(dev_t dev
)
2809 struct mapped_device
*md
;
2810 unsigned minor
= MINOR(dev
);
2812 if (MAJOR(dev
) != _major
|| minor
>= (1 << MINORBITS
))
2815 spin_lock(&_minor_lock
);
2817 md
= idr_find(&_minor_idr
, minor
);
2819 if ((md
== MINOR_ALLOCED
||
2820 (MINOR(disk_devt(dm_disk(md
))) != minor
) ||
2821 dm_deleting_md(md
) ||
2822 test_bit(DMF_FREEING
, &md
->flags
))) {
2830 spin_unlock(&_minor_lock
);
2834 EXPORT_SYMBOL_GPL(dm_get_md
);
2836 void *dm_get_mdptr(struct mapped_device
*md
)
2838 return md
->interface_ptr
;
2841 void dm_set_mdptr(struct mapped_device
*md
, void *ptr
)
2843 md
->interface_ptr
= ptr
;
2846 void dm_get(struct mapped_device
*md
)
2848 atomic_inc(&md
->holders
);
2849 BUG_ON(test_bit(DMF_FREEING
, &md
->flags
));
2852 int dm_hold(struct mapped_device
*md
)
2854 spin_lock(&_minor_lock
);
2855 if (test_bit(DMF_FREEING
, &md
->flags
)) {
2856 spin_unlock(&_minor_lock
);
2860 spin_unlock(&_minor_lock
);
2863 EXPORT_SYMBOL_GPL(dm_hold
);
2865 const char *dm_device_name(struct mapped_device
*md
)
2869 EXPORT_SYMBOL_GPL(dm_device_name
);
2871 static void __dm_destroy(struct mapped_device
*md
, bool wait
)
2873 struct dm_table
*map
;
2878 spin_lock(&_minor_lock
);
2879 idr_replace(&_minor_idr
, MINOR_ALLOCED
, MINOR(disk_devt(dm_disk(md
))));
2880 set_bit(DMF_FREEING
, &md
->flags
);
2881 spin_unlock(&_minor_lock
);
2883 if (dm_request_based(md
) && md
->kworker_task
)
2884 flush_kthread_worker(&md
->kworker
);
2887 * Take suspend_lock so that presuspend and postsuspend methods
2888 * do not race with internal suspend.
2890 mutex_lock(&md
->suspend_lock
);
2891 map
= dm_get_live_table(md
, &srcu_idx
);
2892 if (!dm_suspended_md(md
)) {
2893 dm_table_presuspend_targets(map
);
2894 dm_table_postsuspend_targets(map
);
2896 /* dm_put_live_table must be before msleep, otherwise deadlock is possible */
2897 dm_put_live_table(md
, srcu_idx
);
2898 mutex_unlock(&md
->suspend_lock
);
2901 * Rare, but there may be I/O requests still going to complete,
2902 * for example. Wait for all references to disappear.
2903 * No one should increment the reference count of the mapped_device,
2904 * after the mapped_device state becomes DMF_FREEING.
2907 while (atomic_read(&md
->holders
))
2909 else if (atomic_read(&md
->holders
))
2910 DMWARN("%s: Forcibly removing mapped_device still in use! (%d users)",
2911 dm_device_name(md
), atomic_read(&md
->holders
));
2914 dm_table_destroy(__unbind(md
));
2918 void dm_destroy(struct mapped_device
*md
)
2920 __dm_destroy(md
, true);
2923 void dm_destroy_immediate(struct mapped_device
*md
)
2925 __dm_destroy(md
, false);
2928 void dm_put(struct mapped_device
*md
)
2930 atomic_dec(&md
->holders
);
2932 EXPORT_SYMBOL_GPL(dm_put
);
2934 static int dm_wait_for_completion(struct mapped_device
*md
, int interruptible
)
2937 DECLARE_WAITQUEUE(wait
, current
);
2939 add_wait_queue(&md
->wait
, &wait
);
2942 set_current_state(interruptible
);
2944 if (!md_in_flight(md
))
2947 if (interruptible
== TASK_INTERRUPTIBLE
&&
2948 signal_pending(current
)) {
2955 set_current_state(TASK_RUNNING
);
2957 remove_wait_queue(&md
->wait
, &wait
);
2963 * Process the deferred bios
2965 static void dm_wq_work(struct work_struct
*work
)
2967 struct mapped_device
*md
= container_of(work
, struct mapped_device
,
2971 struct dm_table
*map
;
2973 map
= dm_get_live_table(md
, &srcu_idx
);
2975 while (!test_bit(DMF_BLOCK_IO_FOR_SUSPEND
, &md
->flags
)) {
2976 spin_lock_irq(&md
->deferred_lock
);
2977 c
= bio_list_pop(&md
->deferred
);
2978 spin_unlock_irq(&md
->deferred_lock
);
2983 if (dm_request_based(md
))
2984 generic_make_request(c
);
2986 __split_and_process_bio(md
, map
, c
);
2989 dm_put_live_table(md
, srcu_idx
);
2992 static void dm_queue_flush(struct mapped_device
*md
)
2994 clear_bit(DMF_BLOCK_IO_FOR_SUSPEND
, &md
->flags
);
2995 smp_mb__after_atomic();
2996 queue_work(md
->wq
, &md
->work
);
3000 * Swap in a new table, returning the old one for the caller to destroy.
3002 struct dm_table
*dm_swap_table(struct mapped_device
*md
, struct dm_table
*table
)
3004 struct dm_table
*live_map
= NULL
, *map
= ERR_PTR(-EINVAL
);
3005 struct queue_limits limits
;
3008 mutex_lock(&md
->suspend_lock
);
3010 /* device must be suspended */
3011 if (!dm_suspended_md(md
))
3015 * If the new table has no data devices, retain the existing limits.
3016 * This helps multipath with queue_if_no_path if all paths disappear,
3017 * then new I/O is queued based on these limits, and then some paths
3020 if (dm_table_has_no_data_devices(table
)) {
3021 live_map
= dm_get_live_table_fast(md
);
3023 limits
= md
->queue
->limits
;
3024 dm_put_live_table_fast(md
);
3028 r
= dm_calculate_queue_limits(table
, &limits
);
3035 map
= __bind(md
, table
, &limits
);
3038 mutex_unlock(&md
->suspend_lock
);
3043 * Functions to lock and unlock any filesystem running on the
3046 static int lock_fs(struct mapped_device
*md
)
3050 WARN_ON(md
->frozen_sb
);
3052 md
->frozen_sb
= freeze_bdev(md
->bdev
);
3053 if (IS_ERR(md
->frozen_sb
)) {
3054 r
= PTR_ERR(md
->frozen_sb
);
3055 md
->frozen_sb
= NULL
;
3059 set_bit(DMF_FROZEN
, &md
->flags
);
3064 static void unlock_fs(struct mapped_device
*md
)
3066 if (!test_bit(DMF_FROZEN
, &md
->flags
))
3069 thaw_bdev(md
->bdev
, md
->frozen_sb
);
3070 md
->frozen_sb
= NULL
;
3071 clear_bit(DMF_FROZEN
, &md
->flags
);
3075 * If __dm_suspend returns 0, the device is completely quiescent
3076 * now. There is no request-processing activity. All new requests
3077 * are being added to md->deferred list.
3079 * Caller must hold md->suspend_lock
3081 static int __dm_suspend(struct mapped_device
*md
, struct dm_table
*map
,
3082 unsigned suspend_flags
, int interruptible
)
3084 bool do_lockfs
= suspend_flags
& DM_SUSPEND_LOCKFS_FLAG
;
3085 bool noflush
= suspend_flags
& DM_SUSPEND_NOFLUSH_FLAG
;
3089 * DMF_NOFLUSH_SUSPENDING must be set before presuspend.
3090 * This flag is cleared before dm_suspend returns.
3093 set_bit(DMF_NOFLUSH_SUSPENDING
, &md
->flags
);
3096 * This gets reverted if there's an error later and the targets
3097 * provide the .presuspend_undo hook.
3099 dm_table_presuspend_targets(map
);
3102 * Flush I/O to the device.
3103 * Any I/O submitted after lock_fs() may not be flushed.
3104 * noflush takes precedence over do_lockfs.
3105 * (lock_fs() flushes I/Os and waits for them to complete.)
3107 if (!noflush
&& do_lockfs
) {
3110 dm_table_presuspend_undo_targets(map
);
3116 * Here we must make sure that no processes are submitting requests
3117 * to target drivers i.e. no one may be executing
3118 * __split_and_process_bio. This is called from dm_request and
3121 * To get all processes out of __split_and_process_bio in dm_request,
3122 * we take the write lock. To prevent any process from reentering
3123 * __split_and_process_bio from dm_request and quiesce the thread
3124 * (dm_wq_work), we set BMF_BLOCK_IO_FOR_SUSPEND and call
3125 * flush_workqueue(md->wq).
3127 set_bit(DMF_BLOCK_IO_FOR_SUSPEND
, &md
->flags
);
3129 synchronize_srcu(&md
->io_barrier
);
3132 * Stop md->queue before flushing md->wq in case request-based
3133 * dm defers requests to md->wq from md->queue.
3135 if (dm_request_based(md
)) {
3136 stop_queue(md
->queue
);
3137 if (md
->kworker_task
)
3138 flush_kthread_worker(&md
->kworker
);
3141 flush_workqueue(md
->wq
);
3144 * At this point no more requests are entering target request routines.
3145 * We call dm_wait_for_completion to wait for all existing requests
3148 r
= dm_wait_for_completion(md
, interruptible
);
3151 clear_bit(DMF_NOFLUSH_SUSPENDING
, &md
->flags
);
3153 synchronize_srcu(&md
->io_barrier
);
3155 /* were we interrupted ? */
3159 if (dm_request_based(md
))
3160 start_queue(md
->queue
);
3163 dm_table_presuspend_undo_targets(map
);
3164 /* pushback list is already flushed, so skip flush */
3171 * We need to be able to change a mapping table under a mounted
3172 * filesystem. For example we might want to move some data in
3173 * the background. Before the table can be swapped with
3174 * dm_bind_table, dm_suspend must be called to flush any in
3175 * flight bios and ensure that any further io gets deferred.
3178 * Suspend mechanism in request-based dm.
3180 * 1. Flush all I/Os by lock_fs() if needed.
3181 * 2. Stop dispatching any I/O by stopping the request_queue.
3182 * 3. Wait for all in-flight I/Os to be completed or requeued.
3184 * To abort suspend, start the request_queue.
3186 int dm_suspend(struct mapped_device
*md
, unsigned suspend_flags
)
3188 struct dm_table
*map
= NULL
;
3192 mutex_lock_nested(&md
->suspend_lock
, SINGLE_DEPTH_NESTING
);
3194 if (dm_suspended_md(md
)) {
3199 if (dm_suspended_internally_md(md
)) {
3200 /* already internally suspended, wait for internal resume */
3201 mutex_unlock(&md
->suspend_lock
);
3202 r
= wait_on_bit(&md
->flags
, DMF_SUSPENDED_INTERNALLY
, TASK_INTERRUPTIBLE
);
3208 map
= rcu_dereference_protected(md
->map
, lockdep_is_held(&md
->suspend_lock
));
3210 r
= __dm_suspend(md
, map
, suspend_flags
, TASK_INTERRUPTIBLE
);
3214 set_bit(DMF_SUSPENDED
, &md
->flags
);
3216 dm_table_postsuspend_targets(map
);
3219 mutex_unlock(&md
->suspend_lock
);
3223 static int __dm_resume(struct mapped_device
*md
, struct dm_table
*map
)
3226 int r
= dm_table_resume_targets(map
);
3234 * Flushing deferred I/Os must be done after targets are resumed
3235 * so that mapping of targets can work correctly.
3236 * Request-based dm is queueing the deferred I/Os in its request_queue.
3238 if (dm_request_based(md
))
3239 start_queue(md
->queue
);
3246 int dm_resume(struct mapped_device
*md
)
3249 struct dm_table
*map
= NULL
;
3252 mutex_lock_nested(&md
->suspend_lock
, SINGLE_DEPTH_NESTING
);
3254 if (!dm_suspended_md(md
))
3257 if (dm_suspended_internally_md(md
)) {
3258 /* already internally suspended, wait for internal resume */
3259 mutex_unlock(&md
->suspend_lock
);
3260 r
= wait_on_bit(&md
->flags
, DMF_SUSPENDED_INTERNALLY
, TASK_INTERRUPTIBLE
);
3266 map
= rcu_dereference_protected(md
->map
, lockdep_is_held(&md
->suspend_lock
));
3267 if (!map
|| !dm_table_get_size(map
))
3270 r
= __dm_resume(md
, map
);
3274 clear_bit(DMF_SUSPENDED
, &md
->flags
);
3278 mutex_unlock(&md
->suspend_lock
);
3284 * Internal suspend/resume works like userspace-driven suspend. It waits
3285 * until all bios finish and prevents issuing new bios to the target drivers.
3286 * It may be used only from the kernel.
3289 static void __dm_internal_suspend(struct mapped_device
*md
, unsigned suspend_flags
)
3291 struct dm_table
*map
= NULL
;
3293 if (md
->internal_suspend_count
++)
3294 return; /* nested internal suspend */
3296 if (dm_suspended_md(md
)) {
3297 set_bit(DMF_SUSPENDED_INTERNALLY
, &md
->flags
);
3298 return; /* nest suspend */
3301 map
= rcu_dereference_protected(md
->map
, lockdep_is_held(&md
->suspend_lock
));
3304 * Using TASK_UNINTERRUPTIBLE because only NOFLUSH internal suspend is
3305 * supported. Properly supporting a TASK_INTERRUPTIBLE internal suspend
3306 * would require changing .presuspend to return an error -- avoid this
3307 * until there is a need for more elaborate variants of internal suspend.
3309 (void) __dm_suspend(md
, map
, suspend_flags
, TASK_UNINTERRUPTIBLE
);
3311 set_bit(DMF_SUSPENDED_INTERNALLY
, &md
->flags
);
3313 dm_table_postsuspend_targets(map
);
3316 static void __dm_internal_resume(struct mapped_device
*md
)
3318 BUG_ON(!md
->internal_suspend_count
);
3320 if (--md
->internal_suspend_count
)
3321 return; /* resume from nested internal suspend */
3323 if (dm_suspended_md(md
))
3324 goto done
; /* resume from nested suspend */
3327 * NOTE: existing callers don't need to call dm_table_resume_targets
3328 * (which may fail -- so best to avoid it for now by passing NULL map)
3330 (void) __dm_resume(md
, NULL
);
3333 clear_bit(DMF_SUSPENDED_INTERNALLY
, &md
->flags
);
3334 smp_mb__after_atomic();
3335 wake_up_bit(&md
->flags
, DMF_SUSPENDED_INTERNALLY
);
3338 void dm_internal_suspend_noflush(struct mapped_device
*md
)
3340 mutex_lock(&md
->suspend_lock
);
3341 __dm_internal_suspend(md
, DM_SUSPEND_NOFLUSH_FLAG
);
3342 mutex_unlock(&md
->suspend_lock
);
3344 EXPORT_SYMBOL_GPL(dm_internal_suspend_noflush
);
3346 void dm_internal_resume(struct mapped_device
*md
)
3348 mutex_lock(&md
->suspend_lock
);
3349 __dm_internal_resume(md
);
3350 mutex_unlock(&md
->suspend_lock
);
3352 EXPORT_SYMBOL_GPL(dm_internal_resume
);
3355 * Fast variants of internal suspend/resume hold md->suspend_lock,
3356 * which prevents interaction with userspace-driven suspend.
3359 void dm_internal_suspend_fast(struct mapped_device
*md
)
3361 mutex_lock(&md
->suspend_lock
);
3362 if (dm_suspended_md(md
) || dm_suspended_internally_md(md
))
3365 set_bit(DMF_BLOCK_IO_FOR_SUSPEND
, &md
->flags
);
3366 synchronize_srcu(&md
->io_barrier
);
3367 flush_workqueue(md
->wq
);
3368 dm_wait_for_completion(md
, TASK_UNINTERRUPTIBLE
);
3370 EXPORT_SYMBOL_GPL(dm_internal_suspend_fast
);
3372 void dm_internal_resume_fast(struct mapped_device
*md
)
3374 if (dm_suspended_md(md
) || dm_suspended_internally_md(md
))
3380 mutex_unlock(&md
->suspend_lock
);
3382 EXPORT_SYMBOL_GPL(dm_internal_resume_fast
);
3384 /*-----------------------------------------------------------------
3385 * Event notification.
3386 *---------------------------------------------------------------*/
3387 int dm_kobject_uevent(struct mapped_device
*md
, enum kobject_action action
,
3390 char udev_cookie
[DM_COOKIE_LENGTH
];
3391 char *envp
[] = { udev_cookie
, NULL
};
3394 return kobject_uevent(&disk_to_dev(md
->disk
)->kobj
, action
);
3396 snprintf(udev_cookie
, DM_COOKIE_LENGTH
, "%s=%u",
3397 DM_COOKIE_ENV_VAR_NAME
, cookie
);
3398 return kobject_uevent_env(&disk_to_dev(md
->disk
)->kobj
,
3403 uint32_t dm_next_uevent_seq(struct mapped_device
*md
)
3405 return atomic_add_return(1, &md
->uevent_seq
);
3408 uint32_t dm_get_event_nr(struct mapped_device
*md
)
3410 return atomic_read(&md
->event_nr
);
3413 int dm_wait_event(struct mapped_device
*md
, int event_nr
)
3415 return wait_event_interruptible(md
->eventq
,
3416 (event_nr
!= atomic_read(&md
->event_nr
)));
3419 void dm_uevent_add(struct mapped_device
*md
, struct list_head
*elist
)
3421 unsigned long flags
;
3423 spin_lock_irqsave(&md
->uevent_lock
, flags
);
3424 list_add(elist
, &md
->uevent_list
);
3425 spin_unlock_irqrestore(&md
->uevent_lock
, flags
);
3429 * The gendisk is only valid as long as you have a reference
3432 struct gendisk
*dm_disk(struct mapped_device
*md
)
3436 EXPORT_SYMBOL_GPL(dm_disk
);
3438 struct kobject
*dm_kobject(struct mapped_device
*md
)
3440 return &md
->kobj_holder
.kobj
;
3443 struct mapped_device
*dm_get_from_kobject(struct kobject
*kobj
)
3445 struct mapped_device
*md
;
3447 md
= container_of(kobj
, struct mapped_device
, kobj_holder
.kobj
);
3449 if (test_bit(DMF_FREEING
, &md
->flags
) ||
3457 int dm_suspended_md(struct mapped_device
*md
)
3459 return test_bit(DMF_SUSPENDED
, &md
->flags
);
3462 int dm_suspended_internally_md(struct mapped_device
*md
)
3464 return test_bit(DMF_SUSPENDED_INTERNALLY
, &md
->flags
);
3467 int dm_test_deferred_remove_flag(struct mapped_device
*md
)
3469 return test_bit(DMF_DEFERRED_REMOVE
, &md
->flags
);
3472 int dm_suspended(struct dm_target
*ti
)
3474 return dm_suspended_md(dm_table_get_md(ti
->table
));
3476 EXPORT_SYMBOL_GPL(dm_suspended
);
3478 int dm_noflush_suspending(struct dm_target
*ti
)
3480 return __noflush_suspending(dm_table_get_md(ti
->table
));
3482 EXPORT_SYMBOL_GPL(dm_noflush_suspending
);
3484 struct dm_md_mempools
*dm_alloc_md_mempools(struct mapped_device
*md
, unsigned type
,
3485 unsigned integrity
, unsigned per_bio_data_size
)
3487 struct dm_md_mempools
*pools
= kzalloc(sizeof(*pools
), GFP_KERNEL
);
3488 struct kmem_cache
*cachep
= NULL
;
3489 unsigned int pool_size
= 0;
3490 unsigned int front_pad
;
3495 type
= filter_md_type(type
, md
);
3498 case DM_TYPE_BIO_BASED
:
3500 pool_size
= dm_get_reserved_bio_based_ios();
3501 front_pad
= roundup(per_bio_data_size
, __alignof__(struct dm_target_io
)) + offsetof(struct dm_target_io
, clone
);
3503 case DM_TYPE_REQUEST_BASED
:
3504 cachep
= _rq_tio_cache
;
3505 pool_size
= dm_get_reserved_rq_based_ios();
3506 pools
->rq_pool
= mempool_create_slab_pool(pool_size
, _rq_cache
);
3507 if (!pools
->rq_pool
)
3509 /* fall through to setup remaining rq-based pools */
3510 case DM_TYPE_MQ_REQUEST_BASED
:
3512 pool_size
= dm_get_reserved_rq_based_ios();
3513 front_pad
= offsetof(struct dm_rq_clone_bio_info
, clone
);
3514 /* per_bio_data_size is not used. See __bind_mempools(). */
3515 WARN_ON(per_bio_data_size
!= 0);
3522 pools
->io_pool
= mempool_create_slab_pool(pool_size
, cachep
);
3523 if (!pools
->io_pool
)
3527 pools
->bs
= bioset_create_nobvec(pool_size
, front_pad
);
3531 if (integrity
&& bioset_integrity_create(pools
->bs
, pool_size
))
3537 dm_free_md_mempools(pools
);
3542 void dm_free_md_mempools(struct dm_md_mempools
*pools
)
3547 mempool_destroy(pools
->io_pool
);
3548 mempool_destroy(pools
->rq_pool
);
3551 bioset_free(pools
->bs
);
3556 static int dm_pr_register(struct block_device
*bdev
, u64 old_key
, u64 new_key
,
3559 struct mapped_device
*md
= bdev
->bd_disk
->private_data
;
3560 const struct pr_ops
*ops
;
3561 struct dm_target
*tgt
;
3565 r
= dm_get_live_table_for_ioctl(md
, &tgt
, &bdev
, &mode
, &srcu_idx
);
3569 ops
= bdev
->bd_disk
->fops
->pr_ops
;
3570 if (ops
&& ops
->pr_register
)
3571 r
= ops
->pr_register(bdev
, old_key
, new_key
, flags
);
3575 dm_put_live_table(md
, srcu_idx
);
3579 static int dm_pr_reserve(struct block_device
*bdev
, u64 key
, enum pr_type type
,
3582 struct mapped_device
*md
= bdev
->bd_disk
->private_data
;
3583 const struct pr_ops
*ops
;
3584 struct dm_target
*tgt
;
3588 r
= dm_get_live_table_for_ioctl(md
, &tgt
, &bdev
, &mode
, &srcu_idx
);
3592 ops
= bdev
->bd_disk
->fops
->pr_ops
;
3593 if (ops
&& ops
->pr_reserve
)
3594 r
= ops
->pr_reserve(bdev
, key
, type
, flags
);
3598 dm_put_live_table(md
, srcu_idx
);
3602 static int dm_pr_release(struct block_device
*bdev
, u64 key
, enum pr_type type
)
3604 struct mapped_device
*md
= bdev
->bd_disk
->private_data
;
3605 const struct pr_ops
*ops
;
3606 struct dm_target
*tgt
;
3610 r
= dm_get_live_table_for_ioctl(md
, &tgt
, &bdev
, &mode
, &srcu_idx
);
3614 ops
= bdev
->bd_disk
->fops
->pr_ops
;
3615 if (ops
&& ops
->pr_release
)
3616 r
= ops
->pr_release(bdev
, key
, type
);
3620 dm_put_live_table(md
, srcu_idx
);
3624 static int dm_pr_preempt(struct block_device
*bdev
, u64 old_key
, u64 new_key
,
3625 enum pr_type type
, bool abort
)
3627 struct mapped_device
*md
= bdev
->bd_disk
->private_data
;
3628 const struct pr_ops
*ops
;
3629 struct dm_target
*tgt
;
3633 r
= dm_get_live_table_for_ioctl(md
, &tgt
, &bdev
, &mode
, &srcu_idx
);
3637 ops
= bdev
->bd_disk
->fops
->pr_ops
;
3638 if (ops
&& ops
->pr_preempt
)
3639 r
= ops
->pr_preempt(bdev
, old_key
, new_key
, type
, abort
);
3643 dm_put_live_table(md
, srcu_idx
);
3647 static int dm_pr_clear(struct block_device
*bdev
, u64 key
)
3649 struct mapped_device
*md
= bdev
->bd_disk
->private_data
;
3650 const struct pr_ops
*ops
;
3651 struct dm_target
*tgt
;
3655 r
= dm_get_live_table_for_ioctl(md
, &tgt
, &bdev
, &mode
, &srcu_idx
);
3659 ops
= bdev
->bd_disk
->fops
->pr_ops
;
3660 if (ops
&& ops
->pr_clear
)
3661 r
= ops
->pr_clear(bdev
, key
);
3665 dm_put_live_table(md
, srcu_idx
);
3669 static const struct pr_ops dm_pr_ops
= {
3670 .pr_register
= dm_pr_register
,
3671 .pr_reserve
= dm_pr_reserve
,
3672 .pr_release
= dm_pr_release
,
3673 .pr_preempt
= dm_pr_preempt
,
3674 .pr_clear
= dm_pr_clear
,
3677 static const struct block_device_operations dm_blk_dops
= {
3678 .open
= dm_blk_open
,
3679 .release
= dm_blk_close
,
3680 .ioctl
= dm_blk_ioctl
,
3681 .getgeo
= dm_blk_getgeo
,
3682 .pr_ops
= &dm_pr_ops
,
3683 .owner
= THIS_MODULE
3689 module_init(dm_init
);
3690 module_exit(dm_exit
);
3692 module_param(major
, uint
, 0);
3693 MODULE_PARM_DESC(major
, "The major number of the device mapper");
3695 module_param(reserved_bio_based_ios
, uint
, S_IRUGO
| S_IWUSR
);
3696 MODULE_PARM_DESC(reserved_bio_based_ios
, "Reserved IOs in bio-based mempools");
3698 module_param(reserved_rq_based_ios
, uint
, S_IRUGO
| S_IWUSR
);
3699 MODULE_PARM_DESC(reserved_rq_based_ios
, "Reserved IOs in request-based mempools");
3701 module_param(use_blk_mq
, bool, S_IRUGO
| S_IWUSR
);
3702 MODULE_PARM_DESC(use_blk_mq
, "Use block multiqueue for request-based DM devices");
3704 MODULE_DESCRIPTION(DM_NAME
" driver");
3705 MODULE_AUTHOR("Joe Thornber <dm-devel@redhat.com>");
3706 MODULE_LICENSE("GPL");