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.
10 #include "dm-uevent.h"
12 #include <linux/init.h>
13 #include <linux/module.h>
14 #include <linux/mutex.h>
15 #include <linux/sched/signal.h>
16 #include <linux/blkpg.h>
17 #include <linux/bio.h>
18 #include <linux/mempool.h>
19 #include <linux/dax.h>
20 #include <linux/slab.h>
21 #include <linux/idr.h>
22 #include <linux/uio.h>
23 #include <linux/hdreg.h>
24 #include <linux/delay.h>
25 #include <linux/wait.h>
27 #include <linux/refcount.h>
29 #define DM_MSG_PREFIX "core"
32 * Cookies are numeric values sent with CHANGE and REMOVE
33 * uevents while resuming, removing or renaming the device.
35 #define DM_COOKIE_ENV_VAR_NAME "DM_COOKIE"
36 #define DM_COOKIE_LENGTH 24
38 static const char *_name = DM_NAME;
40 static unsigned int major = 0;
41 static unsigned int _major = 0;
43 static DEFINE_IDR(_minor_idr);
45 static DEFINE_SPINLOCK(_minor_lock);
47 static void do_deferred_remove(struct work_struct *w);
49 static DECLARE_WORK(deferred_remove_work, do_deferred_remove);
51 static struct workqueue_struct *deferred_remove_workqueue;
53 atomic_t dm_global_event_nr = ATOMIC_INIT(0);
54 DECLARE_WAIT_QUEUE_HEAD(dm_global_eventq);
56 void dm_issue_global_event(void)
58 atomic_inc(&dm_global_event_nr);
59 wake_up(&dm_global_eventq);
63 * One of these is allocated per bio.
66 struct mapped_device *md;
70 unsigned long start_time;
71 spinlock_t endio_lock;
72 struct dm_stats_aux stats_aux;
75 #define MINOR_ALLOCED ((void *)-1)
78 * Bits for the md->flags field.
80 #define DMF_BLOCK_IO_FOR_SUSPEND 0
81 #define DMF_SUSPENDED 1
84 #define DMF_DELETING 4
85 #define DMF_NOFLUSH_SUSPENDING 5
86 #define DMF_DEFERRED_REMOVE 6
87 #define DMF_SUSPENDED_INTERNALLY 7
89 #define DM_NUMA_NODE NUMA_NO_NODE
90 static int dm_numa_node = DM_NUMA_NODE;
93 * For mempools pre-allocation at the table loading time.
95 struct dm_md_mempools {
100 struct table_device {
101 struct list_head list;
103 struct dm_dev dm_dev;
106 static struct kmem_cache *_io_cache;
107 static struct kmem_cache *_rq_tio_cache;
108 static struct kmem_cache *_rq_cache;
111 * Bio-based DM's mempools' reserved IOs set by the user.
113 #define RESERVED_BIO_BASED_IOS 16
114 static unsigned reserved_bio_based_ios = RESERVED_BIO_BASED_IOS;
116 static int __dm_get_module_param_int(int *module_param, int min, int max)
118 int param = READ_ONCE(*module_param);
119 int modified_param = 0;
120 bool modified = true;
123 modified_param = min;
124 else if (param > max)
125 modified_param = max;
130 (void)cmpxchg(module_param, param, modified_param);
131 param = modified_param;
137 unsigned __dm_get_module_param(unsigned *module_param,
138 unsigned def, unsigned max)
140 unsigned param = READ_ONCE(*module_param);
141 unsigned modified_param = 0;
144 modified_param = def;
145 else if (param > max)
146 modified_param = max;
148 if (modified_param) {
149 (void)cmpxchg(module_param, param, modified_param);
150 param = modified_param;
156 unsigned dm_get_reserved_bio_based_ios(void)
158 return __dm_get_module_param(&reserved_bio_based_ios,
159 RESERVED_BIO_BASED_IOS, DM_RESERVED_MAX_IOS);
161 EXPORT_SYMBOL_GPL(dm_get_reserved_bio_based_ios);
163 static unsigned dm_get_numa_node(void)
165 return __dm_get_module_param_int(&dm_numa_node,
166 DM_NUMA_NODE, num_online_nodes() - 1);
169 static int __init local_init(void)
173 /* allocate a slab for the dm_ios */
174 _io_cache = KMEM_CACHE(dm_io, 0);
178 _rq_tio_cache = KMEM_CACHE(dm_rq_target_io, 0);
180 goto out_free_io_cache;
182 _rq_cache = kmem_cache_create("dm_old_clone_request", sizeof(struct request),
183 __alignof__(struct request), 0, NULL);
185 goto out_free_rq_tio_cache;
187 r = dm_uevent_init();
189 goto out_free_rq_cache;
191 deferred_remove_workqueue = alloc_workqueue("kdmremove", WQ_UNBOUND, 1);
192 if (!deferred_remove_workqueue) {
194 goto out_uevent_exit;
198 r = register_blkdev(_major, _name);
200 goto out_free_workqueue;
208 destroy_workqueue(deferred_remove_workqueue);
212 kmem_cache_destroy(_rq_cache);
213 out_free_rq_tio_cache:
214 kmem_cache_destroy(_rq_tio_cache);
216 kmem_cache_destroy(_io_cache);
221 static void local_exit(void)
223 flush_scheduled_work();
224 destroy_workqueue(deferred_remove_workqueue);
226 kmem_cache_destroy(_rq_cache);
227 kmem_cache_destroy(_rq_tio_cache);
228 kmem_cache_destroy(_io_cache);
229 unregister_blkdev(_major, _name);
234 DMINFO("cleaned up");
237 static int (*_inits[])(void) __initdata = {
248 static void (*_exits[])(void) = {
259 static int __init dm_init(void)
261 const int count = ARRAY_SIZE(_inits);
265 for (i = 0; i < count; i++) {
280 static void __exit dm_exit(void)
282 int i = ARRAY_SIZE(_exits);
288 * Should be empty by this point.
290 idr_destroy(&_minor_idr);
294 * Block device functions
296 int dm_deleting_md(struct mapped_device *md)
298 return test_bit(DMF_DELETING, &md->flags);
301 static int dm_blk_open(struct block_device *bdev, fmode_t mode)
303 struct mapped_device *md;
305 spin_lock(&_minor_lock);
307 md = bdev->bd_disk->private_data;
311 if (test_bit(DMF_FREEING, &md->flags) ||
312 dm_deleting_md(md)) {
318 atomic_inc(&md->open_count);
320 spin_unlock(&_minor_lock);
322 return md ? 0 : -ENXIO;
325 static void dm_blk_close(struct gendisk *disk, fmode_t mode)
327 struct mapped_device *md;
329 spin_lock(&_minor_lock);
331 md = disk->private_data;
335 if (atomic_dec_and_test(&md->open_count) &&
336 (test_bit(DMF_DEFERRED_REMOVE, &md->flags)))
337 queue_work(deferred_remove_workqueue, &deferred_remove_work);
341 spin_unlock(&_minor_lock);
344 int dm_open_count(struct mapped_device *md)
346 return atomic_read(&md->open_count);
350 * Guarantees nothing is using the device before it's deleted.
352 int dm_lock_for_deletion(struct mapped_device *md, bool mark_deferred, bool only_deferred)
356 spin_lock(&_minor_lock);
358 if (dm_open_count(md)) {
361 set_bit(DMF_DEFERRED_REMOVE, &md->flags);
362 } else if (only_deferred && !test_bit(DMF_DEFERRED_REMOVE, &md->flags))
365 set_bit(DMF_DELETING, &md->flags);
367 spin_unlock(&_minor_lock);
372 int dm_cancel_deferred_remove(struct mapped_device *md)
376 spin_lock(&_minor_lock);
378 if (test_bit(DMF_DELETING, &md->flags))
381 clear_bit(DMF_DEFERRED_REMOVE, &md->flags);
383 spin_unlock(&_minor_lock);
388 static void do_deferred_remove(struct work_struct *w)
390 dm_deferred_remove();
393 sector_t dm_get_size(struct mapped_device *md)
395 return get_capacity(md->disk);
398 struct request_queue *dm_get_md_queue(struct mapped_device *md)
403 struct dm_stats *dm_get_stats(struct mapped_device *md)
408 static int dm_blk_getgeo(struct block_device *bdev, struct hd_geometry *geo)
410 struct mapped_device *md = bdev->bd_disk->private_data;
412 return dm_get_geometry(md, geo);
415 static int dm_grab_bdev_for_ioctl(struct mapped_device *md,
416 struct block_device **bdev,
419 struct dm_target *tgt;
420 struct dm_table *map;
425 map = dm_get_live_table(md, &srcu_idx);
426 if (!map || !dm_table_get_size(map))
429 /* We only support devices that have a single target */
430 if (dm_table_get_num_targets(map) != 1)
433 tgt = dm_table_get_target(map, 0);
434 if (!tgt->type->prepare_ioctl)
437 if (dm_suspended_md(md)) {
442 r = tgt->type->prepare_ioctl(tgt, bdev, mode);
447 dm_put_live_table(md, srcu_idx);
451 dm_put_live_table(md, srcu_idx);
452 if (r == -ENOTCONN && !fatal_signal_pending(current)) {
459 static int dm_blk_ioctl(struct block_device *bdev, fmode_t mode,
460 unsigned int cmd, unsigned long arg)
462 struct mapped_device *md = bdev->bd_disk->private_data;
465 r = dm_grab_bdev_for_ioctl(md, &bdev, &mode);
471 * Target determined this ioctl is being issued against a
472 * subset of the parent bdev; require extra privileges.
474 if (!capable(CAP_SYS_RAWIO)) {
476 "%s: sending ioctl %x to DM device without required privilege.",
483 r = __blkdev_driver_ioctl(bdev, mode, cmd, arg);
489 static struct dm_io *alloc_io(struct mapped_device *md)
491 return mempool_alloc(md->io_pool, GFP_NOIO);
494 static void free_io(struct mapped_device *md, struct dm_io *io)
496 mempool_free(io, md->io_pool);
499 static void free_tio(struct dm_target_io *tio)
501 bio_put(&tio->clone);
504 int md_in_flight(struct mapped_device *md)
506 return atomic_read(&md->pending[READ]) +
507 atomic_read(&md->pending[WRITE]);
510 static void start_io_acct(struct dm_io *io)
512 struct mapped_device *md = io->md;
513 struct bio *bio = io->bio;
515 int rw = bio_data_dir(bio);
517 io->start_time = jiffies;
519 cpu = part_stat_lock();
520 part_round_stats(md->queue, cpu, &dm_disk(md)->part0);
522 atomic_set(&dm_disk(md)->part0.in_flight[rw],
523 atomic_inc_return(&md->pending[rw]));
525 if (unlikely(dm_stats_used(&md->stats)))
526 dm_stats_account_io(&md->stats, bio_data_dir(bio),
527 bio->bi_iter.bi_sector, bio_sectors(bio),
528 false, 0, &io->stats_aux);
531 static void end_io_acct(struct dm_io *io)
533 struct mapped_device *md = io->md;
534 struct bio *bio = io->bio;
535 unsigned long duration = jiffies - io->start_time;
537 int rw = bio_data_dir(bio);
539 generic_end_io_acct(md->queue, rw, &dm_disk(md)->part0, io->start_time);
541 if (unlikely(dm_stats_used(&md->stats)))
542 dm_stats_account_io(&md->stats, bio_data_dir(bio),
543 bio->bi_iter.bi_sector, bio_sectors(bio),
544 true, duration, &io->stats_aux);
547 * After this is decremented the bio must not be touched if it is
550 pending = atomic_dec_return(&md->pending[rw]);
551 atomic_set(&dm_disk(md)->part0.in_flight[rw], pending);
552 pending += atomic_read(&md->pending[rw^0x1]);
554 /* nudge anyone waiting on suspend queue */
560 * Add the bio to the list of deferred io.
562 static void queue_io(struct mapped_device *md, struct bio *bio)
566 spin_lock_irqsave(&md->deferred_lock, flags);
567 bio_list_add(&md->deferred, bio);
568 spin_unlock_irqrestore(&md->deferred_lock, flags);
569 queue_work(md->wq, &md->work);
573 * Everyone (including functions in this file), should use this
574 * function to access the md->map field, and make sure they call
575 * dm_put_live_table() when finished.
577 struct dm_table *dm_get_live_table(struct mapped_device *md, int *srcu_idx) __acquires(md->io_barrier)
579 *srcu_idx = srcu_read_lock(&md->io_barrier);
581 return srcu_dereference(md->map, &md->io_barrier);
584 void dm_put_live_table(struct mapped_device *md, int srcu_idx) __releases(md->io_barrier)
586 srcu_read_unlock(&md->io_barrier, srcu_idx);
589 void dm_sync_table(struct mapped_device *md)
591 synchronize_srcu(&md->io_barrier);
592 synchronize_rcu_expedited();
596 * A fast alternative to dm_get_live_table/dm_put_live_table.
597 * The caller must not block between these two functions.
599 static struct dm_table *dm_get_live_table_fast(struct mapped_device *md) __acquires(RCU)
602 return rcu_dereference(md->map);
605 static void dm_put_live_table_fast(struct mapped_device *md) __releases(RCU)
611 * Open a table device so we can use it as a map destination.
613 static int open_table_device(struct table_device *td, dev_t dev,
614 struct mapped_device *md)
616 static char *_claim_ptr = "I belong to device-mapper";
617 struct block_device *bdev;
621 BUG_ON(td->dm_dev.bdev);
623 bdev = blkdev_get_by_dev(dev, td->dm_dev.mode | FMODE_EXCL, _claim_ptr);
625 return PTR_ERR(bdev);
627 r = bd_link_disk_holder(bdev, dm_disk(md));
629 blkdev_put(bdev, td->dm_dev.mode | FMODE_EXCL);
633 td->dm_dev.bdev = bdev;
634 td->dm_dev.dax_dev = dax_get_by_host(bdev->bd_disk->disk_name);
639 * Close a table device that we've been using.
641 static void close_table_device(struct table_device *td, struct mapped_device *md)
643 if (!td->dm_dev.bdev)
646 bd_unlink_disk_holder(td->dm_dev.bdev, dm_disk(md));
647 blkdev_put(td->dm_dev.bdev, td->dm_dev.mode | FMODE_EXCL);
648 put_dax(td->dm_dev.dax_dev);
649 td->dm_dev.bdev = NULL;
650 td->dm_dev.dax_dev = NULL;
653 static struct table_device *find_table_device(struct list_head *l, dev_t dev,
655 struct table_device *td;
657 list_for_each_entry(td, l, list)
658 if (td->dm_dev.bdev->bd_dev == dev && td->dm_dev.mode == mode)
664 int dm_get_table_device(struct mapped_device *md, dev_t dev, fmode_t mode,
665 struct dm_dev **result) {
667 struct table_device *td;
669 mutex_lock(&md->table_devices_lock);
670 td = find_table_device(&md->table_devices, dev, mode);
672 td = kmalloc_node(sizeof(*td), GFP_KERNEL, md->numa_node_id);
674 mutex_unlock(&md->table_devices_lock);
678 td->dm_dev.mode = mode;
679 td->dm_dev.bdev = NULL;
681 if ((r = open_table_device(td, dev, md))) {
682 mutex_unlock(&md->table_devices_lock);
687 format_dev_t(td->dm_dev.name, dev);
689 refcount_set(&td->count, 1);
690 list_add(&td->list, &md->table_devices);
692 refcount_inc(&td->count);
694 mutex_unlock(&md->table_devices_lock);
696 *result = &td->dm_dev;
699 EXPORT_SYMBOL_GPL(dm_get_table_device);
701 void dm_put_table_device(struct mapped_device *md, struct dm_dev *d)
703 struct table_device *td = container_of(d, struct table_device, dm_dev);
705 mutex_lock(&md->table_devices_lock);
706 if (refcount_dec_and_test(&td->count)) {
707 close_table_device(td, md);
711 mutex_unlock(&md->table_devices_lock);
713 EXPORT_SYMBOL(dm_put_table_device);
715 static void free_table_devices(struct list_head *devices)
717 struct list_head *tmp, *next;
719 list_for_each_safe(tmp, next, devices) {
720 struct table_device *td = list_entry(tmp, struct table_device, list);
722 DMWARN("dm_destroy: %s still exists with %d references",
723 td->dm_dev.name, refcount_read(&td->count));
729 * Get the geometry associated with a dm device
731 int dm_get_geometry(struct mapped_device *md, struct hd_geometry *geo)
739 * Set the geometry of a device.
741 int dm_set_geometry(struct mapped_device *md, struct hd_geometry *geo)
743 sector_t sz = (sector_t)geo->cylinders * geo->heads * geo->sectors;
745 if (geo->start > sz) {
746 DMWARN("Start sector is beyond the geometry limits.");
755 /*-----------------------------------------------------------------
757 * A more elegant soln is in the works that uses the queue
758 * merge fn, unfortunately there are a couple of changes to
759 * the block layer that I want to make for this. So in the
760 * interests of getting something for people to use I give
761 * you this clearly demarcated crap.
762 *---------------------------------------------------------------*/
764 static int __noflush_suspending(struct mapped_device *md)
766 return test_bit(DMF_NOFLUSH_SUSPENDING, &md->flags);
770 * Decrements the number of outstanding ios that a bio has been
771 * cloned into, completing the original io if necc.
773 static void dec_pending(struct dm_io *io, blk_status_t error)
776 blk_status_t io_error;
778 struct mapped_device *md = io->md;
780 /* Push-back supersedes any I/O errors */
781 if (unlikely(error)) {
782 spin_lock_irqsave(&io->endio_lock, flags);
783 if (!(io->status == BLK_STS_DM_REQUEUE &&
784 __noflush_suspending(md)))
786 spin_unlock_irqrestore(&io->endio_lock, flags);
789 if (atomic_dec_and_test(&io->io_count)) {
790 if (io->status == BLK_STS_DM_REQUEUE) {
792 * Target requested pushing back the I/O.
794 spin_lock_irqsave(&md->deferred_lock, flags);
795 if (__noflush_suspending(md))
796 bio_list_add_head(&md->deferred, io->bio);
798 /* noflush suspend was interrupted. */
799 io->status = BLK_STS_IOERR;
800 spin_unlock_irqrestore(&md->deferred_lock, flags);
803 io_error = io->status;
808 if (io_error == BLK_STS_DM_REQUEUE)
811 if ((bio->bi_opf & REQ_PREFLUSH) && bio->bi_iter.bi_size) {
813 * Preflush done for flush with data, reissue
814 * without REQ_PREFLUSH.
816 bio->bi_opf &= ~REQ_PREFLUSH;
819 /* done with normal IO or empty flush */
820 bio->bi_status = io_error;
826 void disable_write_same(struct mapped_device *md)
828 struct queue_limits *limits = dm_get_queue_limits(md);
830 /* device doesn't really support WRITE SAME, disable it */
831 limits->max_write_same_sectors = 0;
834 void disable_write_zeroes(struct mapped_device *md)
836 struct queue_limits *limits = dm_get_queue_limits(md);
838 /* device doesn't really support WRITE ZEROES, disable it */
839 limits->max_write_zeroes_sectors = 0;
842 static void clone_endio(struct bio *bio)
844 blk_status_t error = bio->bi_status;
845 struct dm_target_io *tio = container_of(bio, struct dm_target_io, clone);
846 struct dm_io *io = tio->io;
847 struct mapped_device *md = tio->io->md;
848 dm_endio_fn endio = tio->ti->type->end_io;
850 if (unlikely(error == BLK_STS_TARGET)) {
851 if (bio_op(bio) == REQ_OP_WRITE_SAME &&
852 !bio->bi_disk->queue->limits.max_write_same_sectors)
853 disable_write_same(md);
854 if (bio_op(bio) == REQ_OP_WRITE_ZEROES &&
855 !bio->bi_disk->queue->limits.max_write_zeroes_sectors)
856 disable_write_zeroes(md);
860 int r = endio(tio->ti, bio, &error);
862 case DM_ENDIO_REQUEUE:
863 error = BLK_STS_DM_REQUEUE;
867 case DM_ENDIO_INCOMPLETE:
868 /* The target will handle the io */
871 DMWARN("unimplemented target endio return value: %d", r);
877 dec_pending(io, error);
881 * Return maximum size of I/O possible at the supplied sector up to the current
884 static sector_t max_io_len_target_boundary(sector_t sector, struct dm_target *ti)
886 sector_t target_offset = dm_target_offset(ti, sector);
888 return ti->len - target_offset;
891 static sector_t max_io_len(sector_t sector, struct dm_target *ti)
893 sector_t len = max_io_len_target_boundary(sector, ti);
894 sector_t offset, max_len;
897 * Does the target need to split even further?
899 if (ti->max_io_len) {
900 offset = dm_target_offset(ti, sector);
901 if (unlikely(ti->max_io_len & (ti->max_io_len - 1)))
902 max_len = sector_div(offset, ti->max_io_len);
904 max_len = offset & (ti->max_io_len - 1);
905 max_len = ti->max_io_len - max_len;
914 int dm_set_target_max_io_len(struct dm_target *ti, sector_t len)
916 if (len > UINT_MAX) {
917 DMERR("Specified maximum size of target IO (%llu) exceeds limit (%u)",
918 (unsigned long long)len, UINT_MAX);
919 ti->error = "Maximum size of target IO is too large";
924 * BIO based queue uses its own splitting. When multipage bvecs
925 * is switched on, size of the incoming bio may be too big to
926 * be handled in some targets, such as crypt.
928 * When these targets are ready for the big bio, we can remove
931 ti->max_io_len = min_t(uint32_t, len, BIO_MAX_PAGES * PAGE_SIZE);
935 EXPORT_SYMBOL_GPL(dm_set_target_max_io_len);
937 static struct dm_target *dm_dax_get_live_target(struct mapped_device *md,
938 sector_t sector, int *srcu_idx)
940 struct dm_table *map;
941 struct dm_target *ti;
943 map = dm_get_live_table(md, srcu_idx);
947 ti = dm_table_find_target(map, sector);
948 if (!dm_target_is_valid(ti))
954 static long dm_dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff,
955 long nr_pages, void **kaddr, pfn_t *pfn)
957 struct mapped_device *md = dax_get_private(dax_dev);
958 sector_t sector = pgoff * PAGE_SECTORS;
959 struct dm_target *ti;
960 long len, ret = -EIO;
963 ti = dm_dax_get_live_target(md, sector, &srcu_idx);
967 if (!ti->type->direct_access)
969 len = max_io_len(sector, ti) / PAGE_SECTORS;
972 nr_pages = min(len, nr_pages);
973 if (ti->type->direct_access)
974 ret = ti->type->direct_access(ti, pgoff, nr_pages, kaddr, pfn);
977 dm_put_live_table(md, srcu_idx);
982 static size_t dm_dax_copy_from_iter(struct dax_device *dax_dev, pgoff_t pgoff,
983 void *addr, size_t bytes, struct iov_iter *i)
985 struct mapped_device *md = dax_get_private(dax_dev);
986 sector_t sector = pgoff * PAGE_SECTORS;
987 struct dm_target *ti;
991 ti = dm_dax_get_live_target(md, sector, &srcu_idx);
995 if (!ti->type->dax_copy_from_iter) {
996 ret = copy_from_iter(addr, bytes, i);
999 ret = ti->type->dax_copy_from_iter(ti, pgoff, addr, bytes, i);
1001 dm_put_live_table(md, srcu_idx);
1007 * A target may call dm_accept_partial_bio only from the map routine. It is
1008 * allowed for all bio types except REQ_PREFLUSH.
1010 * dm_accept_partial_bio informs the dm that the target only wants to process
1011 * additional n_sectors sectors of the bio and the rest of the data should be
1012 * sent in a next bio.
1014 * A diagram that explains the arithmetics:
1015 * +--------------------+---------------+-------+
1017 * +--------------------+---------------+-------+
1019 * <-------------- *tio->len_ptr --------------->
1020 * <------- bi_size ------->
1023 * Region 1 was already iterated over with bio_advance or similar function.
1024 * (it may be empty if the target doesn't use bio_advance)
1025 * Region 2 is the remaining bio size that the target wants to process.
1026 * (it may be empty if region 1 is non-empty, although there is no reason
1028 * The target requires that region 3 is to be sent in the next bio.
1030 * If the target wants to receive multiple copies of the bio (via num_*bios, etc),
1031 * the partially processed part (the sum of regions 1+2) must be the same for all
1032 * copies of the bio.
1034 void dm_accept_partial_bio(struct bio *bio, unsigned n_sectors)
1036 struct dm_target_io *tio = container_of(bio, struct dm_target_io, clone);
1037 unsigned bi_size = bio->bi_iter.bi_size >> SECTOR_SHIFT;
1038 BUG_ON(bio->bi_opf & REQ_PREFLUSH);
1039 BUG_ON(bi_size > *tio->len_ptr);
1040 BUG_ON(n_sectors > bi_size);
1041 *tio->len_ptr -= bi_size - n_sectors;
1042 bio->bi_iter.bi_size = n_sectors << SECTOR_SHIFT;
1044 EXPORT_SYMBOL_GPL(dm_accept_partial_bio);
1047 * The zone descriptors obtained with a zone report indicate
1048 * zone positions within the target device. The zone descriptors
1049 * must be remapped to match their position within the dm device.
1050 * A target may call dm_remap_zone_report after completion of a
1051 * REQ_OP_ZONE_REPORT bio to remap the zone descriptors obtained
1052 * from the target device mapping to the dm device.
1054 void dm_remap_zone_report(struct dm_target *ti, struct bio *bio, sector_t start)
1056 #ifdef CONFIG_BLK_DEV_ZONED
1057 struct dm_target_io *tio = container_of(bio, struct dm_target_io, clone);
1058 struct bio *report_bio = tio->io->bio;
1059 struct blk_zone_report_hdr *hdr = NULL;
1060 struct blk_zone *zone;
1061 unsigned int nr_rep = 0;
1063 struct bio_vec bvec;
1064 struct bvec_iter iter;
1071 * Remap the start sector of the reported zones. For sequential zones,
1072 * also remap the write pointer position.
1074 bio_for_each_segment(bvec, report_bio, iter) {
1075 addr = kmap_atomic(bvec.bv_page);
1077 /* Remember the report header in the first page */
1080 ofst = sizeof(struct blk_zone_report_hdr);
1084 /* Set zones start sector */
1085 while (hdr->nr_zones && ofst < bvec.bv_len) {
1087 if (zone->start >= start + ti->len) {
1091 zone->start = zone->start + ti->begin - start;
1092 if (zone->type != BLK_ZONE_TYPE_CONVENTIONAL) {
1093 if (zone->cond == BLK_ZONE_COND_FULL)
1094 zone->wp = zone->start + zone->len;
1095 else if (zone->cond == BLK_ZONE_COND_EMPTY)
1096 zone->wp = zone->start;
1098 zone->wp = zone->wp + ti->begin - start;
1100 ofst += sizeof(struct blk_zone);
1106 kunmap_atomic(addr);
1113 hdr->nr_zones = nr_rep;
1117 bio_advance(report_bio, report_bio->bi_iter.bi_size);
1119 #else /* !CONFIG_BLK_DEV_ZONED */
1120 bio->bi_status = BLK_STS_NOTSUPP;
1123 EXPORT_SYMBOL_GPL(dm_remap_zone_report);
1126 * Flush current->bio_list when the target map method blocks.
1127 * This fixes deadlocks in snapshot and possibly in other targets.
1130 struct blk_plug plug;
1131 struct blk_plug_cb cb;
1134 static void flush_current_bio_list(struct blk_plug_cb *cb, bool from_schedule)
1136 struct dm_offload *o = container_of(cb, struct dm_offload, cb);
1137 struct bio_list list;
1141 INIT_LIST_HEAD(&o->cb.list);
1143 if (unlikely(!current->bio_list))
1146 for (i = 0; i < 2; i++) {
1147 list = current->bio_list[i];
1148 bio_list_init(¤t->bio_list[i]);
1150 while ((bio = bio_list_pop(&list))) {
1151 struct bio_set *bs = bio->bi_pool;
1152 if (unlikely(!bs) || bs == fs_bio_set ||
1153 !bs->rescue_workqueue) {
1154 bio_list_add(¤t->bio_list[i], bio);
1158 spin_lock(&bs->rescue_lock);
1159 bio_list_add(&bs->rescue_list, bio);
1160 queue_work(bs->rescue_workqueue, &bs->rescue_work);
1161 spin_unlock(&bs->rescue_lock);
1166 static void dm_offload_start(struct dm_offload *o)
1168 blk_start_plug(&o->plug);
1169 o->cb.callback = flush_current_bio_list;
1170 list_add(&o->cb.list, ¤t->plug->cb_list);
1173 static void dm_offload_end(struct dm_offload *o)
1175 list_del(&o->cb.list);
1176 blk_finish_plug(&o->plug);
1179 static void __map_bio(struct dm_target_io *tio)
1183 struct dm_offload o;
1184 struct bio *clone = &tio->clone;
1185 struct dm_target *ti = tio->ti;
1187 clone->bi_end_io = clone_endio;
1190 * Map the clone. If r == 0 we don't need to do
1191 * anything, the target has assumed ownership of
1194 atomic_inc(&tio->io->io_count);
1195 sector = clone->bi_iter.bi_sector;
1197 dm_offload_start(&o);
1198 r = ti->type->map(ti, clone);
1202 case DM_MAPIO_SUBMITTED:
1204 case DM_MAPIO_REMAPPED:
1205 /* the bio has been remapped so dispatch it */
1206 trace_block_bio_remap(clone->bi_disk->queue, clone,
1207 bio_dev(tio->io->bio), sector);
1208 generic_make_request(clone);
1211 dec_pending(tio->io, BLK_STS_IOERR);
1214 case DM_MAPIO_REQUEUE:
1215 dec_pending(tio->io, BLK_STS_DM_REQUEUE);
1219 DMWARN("unimplemented target map return value: %d", r);
1225 struct mapped_device *md;
1226 struct dm_table *map;
1230 unsigned sector_count;
1233 static void bio_setup_sector(struct bio *bio, sector_t sector, unsigned len)
1235 bio->bi_iter.bi_sector = sector;
1236 bio->bi_iter.bi_size = to_bytes(len);
1240 * Creates a bio that consists of range of complete bvecs.
1242 static int clone_bio(struct dm_target_io *tio, struct bio *bio,
1243 sector_t sector, unsigned len)
1245 struct bio *clone = &tio->clone;
1247 __bio_clone_fast(clone, bio);
1249 if (unlikely(bio_integrity(bio) != NULL)) {
1252 if (unlikely(!dm_target_has_integrity(tio->ti->type) &&
1253 !dm_target_passes_integrity(tio->ti->type))) {
1254 DMWARN("%s: the target %s doesn't support integrity data.",
1255 dm_device_name(tio->io->md),
1256 tio->ti->type->name);
1260 r = bio_integrity_clone(clone, bio, GFP_NOIO);
1265 if (bio_op(bio) != REQ_OP_ZONE_REPORT)
1266 bio_advance(clone, to_bytes(sector - clone->bi_iter.bi_sector));
1267 clone->bi_iter.bi_size = to_bytes(len);
1269 if (unlikely(bio_integrity(bio) != NULL))
1270 bio_integrity_trim(clone);
1275 static struct dm_target_io *alloc_tio(struct clone_info *ci,
1276 struct dm_target *ti,
1277 unsigned target_bio_nr)
1279 struct dm_target_io *tio;
1282 clone = bio_alloc_bioset(GFP_NOIO, 0, ci->md->bs);
1283 tio = container_of(clone, struct dm_target_io, clone);
1287 tio->target_bio_nr = target_bio_nr;
1292 static void __clone_and_map_simple_bio(struct clone_info *ci,
1293 struct dm_target *ti,
1294 unsigned target_bio_nr, unsigned *len)
1296 struct dm_target_io *tio = alloc_tio(ci, ti, target_bio_nr);
1297 struct bio *clone = &tio->clone;
1301 __bio_clone_fast(clone, ci->bio);
1303 bio_setup_sector(clone, ci->sector, *len);
1308 static void __send_duplicate_bios(struct clone_info *ci, struct dm_target *ti,
1309 unsigned num_bios, unsigned *len)
1311 unsigned target_bio_nr;
1313 for (target_bio_nr = 0; target_bio_nr < num_bios; target_bio_nr++)
1314 __clone_and_map_simple_bio(ci, ti, target_bio_nr, len);
1317 static int __send_empty_flush(struct clone_info *ci)
1319 unsigned target_nr = 0;
1320 struct dm_target *ti;
1322 BUG_ON(bio_has_data(ci->bio));
1323 while ((ti = dm_table_get_target(ci->map, target_nr++)))
1324 __send_duplicate_bios(ci, ti, ti->num_flush_bios, NULL);
1329 static int __clone_and_map_data_bio(struct clone_info *ci, struct dm_target *ti,
1330 sector_t sector, unsigned *len)
1332 struct bio *bio = ci->bio;
1333 struct dm_target_io *tio;
1334 unsigned target_bio_nr;
1335 unsigned num_target_bios = 1;
1339 * Does the target want to receive duplicate copies of the bio?
1341 if (bio_data_dir(bio) == WRITE && ti->num_write_bios)
1342 num_target_bios = ti->num_write_bios(ti, bio);
1344 for (target_bio_nr = 0; target_bio_nr < num_target_bios; target_bio_nr++) {
1345 tio = alloc_tio(ci, ti, target_bio_nr);
1347 r = clone_bio(tio, bio, sector, *len);
1358 typedef unsigned (*get_num_bios_fn)(struct dm_target *ti);
1360 static unsigned get_num_discard_bios(struct dm_target *ti)
1362 return ti->num_discard_bios;
1365 static unsigned get_num_write_same_bios(struct dm_target *ti)
1367 return ti->num_write_same_bios;
1370 static unsigned get_num_write_zeroes_bios(struct dm_target *ti)
1372 return ti->num_write_zeroes_bios;
1375 typedef bool (*is_split_required_fn)(struct dm_target *ti);
1377 static bool is_split_required_for_discard(struct dm_target *ti)
1379 return ti->split_discard_bios;
1382 static int __send_changing_extent_only(struct clone_info *ci,
1383 get_num_bios_fn get_num_bios,
1384 is_split_required_fn is_split_required)
1386 struct dm_target *ti;
1391 ti = dm_table_find_target(ci->map, ci->sector);
1392 if (!dm_target_is_valid(ti))
1396 * Even though the device advertised support for this type of
1397 * request, that does not mean every target supports it, and
1398 * reconfiguration might also have changed that since the
1399 * check was performed.
1401 num_bios = get_num_bios ? get_num_bios(ti) : 0;
1405 if (is_split_required && !is_split_required(ti))
1406 len = min((sector_t)ci->sector_count, max_io_len_target_boundary(ci->sector, ti));
1408 len = min((sector_t)ci->sector_count, max_io_len(ci->sector, ti));
1410 __send_duplicate_bios(ci, ti, num_bios, &len);
1413 } while (ci->sector_count -= len);
1418 static int __send_discard(struct clone_info *ci)
1420 return __send_changing_extent_only(ci, get_num_discard_bios,
1421 is_split_required_for_discard);
1424 static int __send_write_same(struct clone_info *ci)
1426 return __send_changing_extent_only(ci, get_num_write_same_bios, NULL);
1429 static int __send_write_zeroes(struct clone_info *ci)
1431 return __send_changing_extent_only(ci, get_num_write_zeroes_bios, NULL);
1435 * Select the correct strategy for processing a non-flush bio.
1437 static int __split_and_process_non_flush(struct clone_info *ci)
1439 struct bio *bio = ci->bio;
1440 struct dm_target *ti;
1444 if (unlikely(bio_op(bio) == REQ_OP_DISCARD))
1445 return __send_discard(ci);
1446 else if (unlikely(bio_op(bio) == REQ_OP_WRITE_SAME))
1447 return __send_write_same(ci);
1448 else if (unlikely(bio_op(bio) == REQ_OP_WRITE_ZEROES))
1449 return __send_write_zeroes(ci);
1451 ti = dm_table_find_target(ci->map, ci->sector);
1452 if (!dm_target_is_valid(ti))
1455 if (bio_op(bio) == REQ_OP_ZONE_REPORT)
1456 len = ci->sector_count;
1458 len = min_t(sector_t, max_io_len(ci->sector, ti),
1461 r = __clone_and_map_data_bio(ci, ti, ci->sector, &len);
1466 ci->sector_count -= len;
1472 * Entry point to split a bio into clones and submit them to the targets.
1474 static void __split_and_process_bio(struct mapped_device *md,
1475 struct dm_table *map, struct bio *bio)
1477 struct clone_info ci;
1480 if (unlikely(!map)) {
1487 ci.io = alloc_io(md);
1489 atomic_set(&ci.io->io_count, 1);
1492 spin_lock_init(&ci.io->endio_lock);
1493 ci.sector = bio->bi_iter.bi_sector;
1495 start_io_acct(ci.io);
1497 if (bio->bi_opf & REQ_PREFLUSH) {
1498 ci.bio = &ci.md->flush_bio;
1499 ci.sector_count = 0;
1500 error = __send_empty_flush(&ci);
1501 /* dec_pending submits any data associated with flush */
1502 } else if (bio_op(bio) == REQ_OP_ZONE_RESET) {
1504 ci.sector_count = 0;
1505 error = __split_and_process_non_flush(&ci);
1508 ci.sector_count = bio_sectors(bio);
1509 while (ci.sector_count && !error)
1510 error = __split_and_process_non_flush(&ci);
1513 /* drop the extra reference count */
1514 dec_pending(ci.io, errno_to_blk_status(error));
1516 /*-----------------------------------------------------------------
1518 *---------------------------------------------------------------*/
1521 * The request function that just remaps the bio built up by
1524 static blk_qc_t dm_make_request(struct request_queue *q, struct bio *bio)
1526 int rw = bio_data_dir(bio);
1527 struct mapped_device *md = q->queuedata;
1529 struct dm_table *map;
1531 map = dm_get_live_table(md, &srcu_idx);
1533 generic_start_io_acct(q, rw, bio_sectors(bio), &dm_disk(md)->part0);
1535 /* if we're suspended, we have to queue this io for later */
1536 if (unlikely(test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags))) {
1537 dm_put_live_table(md, srcu_idx);
1539 if (!(bio->bi_opf & REQ_RAHEAD))
1543 return BLK_QC_T_NONE;
1546 __split_and_process_bio(md, map, bio);
1547 dm_put_live_table(md, srcu_idx);
1548 return BLK_QC_T_NONE;
1551 static int dm_any_congested(void *congested_data, int bdi_bits)
1554 struct mapped_device *md = congested_data;
1555 struct dm_table *map;
1557 if (!test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags)) {
1558 if (dm_request_based(md)) {
1560 * With request-based DM we only need to check the
1561 * top-level queue for congestion.
1563 r = md->queue->backing_dev_info->wb.state & bdi_bits;
1565 map = dm_get_live_table_fast(md);
1567 r = dm_table_any_congested(map, bdi_bits);
1568 dm_put_live_table_fast(md);
1575 /*-----------------------------------------------------------------
1576 * An IDR is used to keep track of allocated minor numbers.
1577 *---------------------------------------------------------------*/
1578 static void free_minor(int minor)
1580 spin_lock(&_minor_lock);
1581 idr_remove(&_minor_idr, minor);
1582 spin_unlock(&_minor_lock);
1586 * See if the device with a specific minor # is free.
1588 static int specific_minor(int minor)
1592 if (minor >= (1 << MINORBITS))
1595 idr_preload(GFP_KERNEL);
1596 spin_lock(&_minor_lock);
1598 r = idr_alloc(&_minor_idr, MINOR_ALLOCED, minor, minor + 1, GFP_NOWAIT);
1600 spin_unlock(&_minor_lock);
1603 return r == -ENOSPC ? -EBUSY : r;
1607 static int next_free_minor(int *minor)
1611 idr_preload(GFP_KERNEL);
1612 spin_lock(&_minor_lock);
1614 r = idr_alloc(&_minor_idr, MINOR_ALLOCED, 0, 1 << MINORBITS, GFP_NOWAIT);
1616 spin_unlock(&_minor_lock);
1624 static const struct block_device_operations dm_blk_dops;
1625 static const struct dax_operations dm_dax_ops;
1627 static void dm_wq_work(struct work_struct *work);
1629 void dm_init_md_queue(struct mapped_device *md)
1632 * Initialize data that will only be used by a non-blk-mq DM queue
1633 * - must do so here (in alloc_dev callchain) before queue is used
1635 md->queue->queuedata = md;
1636 md->queue->backing_dev_info->congested_data = md;
1639 void dm_init_normal_md_queue(struct mapped_device *md)
1641 md->use_blk_mq = false;
1642 dm_init_md_queue(md);
1645 * Initialize aspects of queue that aren't relevant for blk-mq
1647 md->queue->backing_dev_info->congested_fn = dm_any_congested;
1650 static void cleanup_mapped_device(struct mapped_device *md)
1653 destroy_workqueue(md->wq);
1654 if (md->kworker_task)
1655 kthread_stop(md->kworker_task);
1656 mempool_destroy(md->io_pool);
1658 bioset_free(md->bs);
1661 kill_dax(md->dax_dev);
1662 put_dax(md->dax_dev);
1667 spin_lock(&_minor_lock);
1668 md->disk->private_data = NULL;
1669 spin_unlock(&_minor_lock);
1670 del_gendisk(md->disk);
1675 blk_cleanup_queue(md->queue);
1677 cleanup_srcu_struct(&md->io_barrier);
1684 dm_mq_cleanup_mapped_device(md);
1688 * Allocate and initialise a blank device with a given minor.
1690 static struct mapped_device *alloc_dev(int minor)
1692 int r, numa_node_id = dm_get_numa_node();
1693 struct dax_device *dax_dev;
1694 struct mapped_device *md;
1697 md = kvzalloc_node(sizeof(*md), GFP_KERNEL, numa_node_id);
1699 DMWARN("unable to allocate device, out of memory.");
1703 if (!try_module_get(THIS_MODULE))
1704 goto bad_module_get;
1706 /* get a minor number for the dev */
1707 if (minor == DM_ANY_MINOR)
1708 r = next_free_minor(&minor);
1710 r = specific_minor(minor);
1714 r = init_srcu_struct(&md->io_barrier);
1716 goto bad_io_barrier;
1718 md->numa_node_id = numa_node_id;
1719 md->use_blk_mq = dm_use_blk_mq_default();
1720 md->init_tio_pdu = false;
1721 md->type = DM_TYPE_NONE;
1722 mutex_init(&md->suspend_lock);
1723 mutex_init(&md->type_lock);
1724 mutex_init(&md->table_devices_lock);
1725 spin_lock_init(&md->deferred_lock);
1726 atomic_set(&md->holders, 1);
1727 atomic_set(&md->open_count, 0);
1728 atomic_set(&md->event_nr, 0);
1729 atomic_set(&md->uevent_seq, 0);
1730 INIT_LIST_HEAD(&md->uevent_list);
1731 INIT_LIST_HEAD(&md->table_devices);
1732 spin_lock_init(&md->uevent_lock);
1734 md->queue = blk_alloc_queue_node(GFP_KERNEL, numa_node_id);
1738 dm_init_md_queue(md);
1740 md->disk = alloc_disk_node(1, numa_node_id);
1744 atomic_set(&md->pending[0], 0);
1745 atomic_set(&md->pending[1], 0);
1746 init_waitqueue_head(&md->wait);
1747 INIT_WORK(&md->work, dm_wq_work);
1748 init_waitqueue_head(&md->eventq);
1749 init_completion(&md->kobj_holder.completion);
1750 md->kworker_task = NULL;
1752 md->disk->major = _major;
1753 md->disk->first_minor = minor;
1754 md->disk->fops = &dm_blk_dops;
1755 md->disk->queue = md->queue;
1756 md->disk->private_data = md;
1757 sprintf(md->disk->disk_name, "dm-%d", minor);
1759 dax_dev = alloc_dax(md, md->disk->disk_name, &dm_dax_ops);
1762 md->dax_dev = dax_dev;
1765 format_dev_t(md->name, MKDEV(_major, minor));
1767 md->wq = alloc_workqueue("kdmflush", WQ_MEM_RECLAIM, 0);
1771 md->bdev = bdget_disk(md->disk, 0);
1775 bio_init(&md->flush_bio, NULL, 0);
1776 bio_set_dev(&md->flush_bio, md->bdev);
1777 md->flush_bio.bi_opf = REQ_OP_WRITE | REQ_PREFLUSH | REQ_SYNC;
1779 dm_stats_init(&md->stats);
1781 /* Populate the mapping, nobody knows we exist yet */
1782 spin_lock(&_minor_lock);
1783 old_md = idr_replace(&_minor_idr, md, minor);
1784 spin_unlock(&_minor_lock);
1786 BUG_ON(old_md != MINOR_ALLOCED);
1791 cleanup_mapped_device(md);
1795 module_put(THIS_MODULE);
1801 static void unlock_fs(struct mapped_device *md);
1803 static void free_dev(struct mapped_device *md)
1805 int minor = MINOR(disk_devt(md->disk));
1809 cleanup_mapped_device(md);
1811 free_table_devices(&md->table_devices);
1812 dm_stats_cleanup(&md->stats);
1815 module_put(THIS_MODULE);
1819 static void __bind_mempools(struct mapped_device *md, struct dm_table *t)
1821 struct dm_md_mempools *p = dm_table_get_md_mempools(t);
1824 /* The md already has necessary mempools. */
1825 if (dm_table_bio_based(t)) {
1827 * Reload bioset because front_pad may have changed
1828 * because a different table was loaded.
1830 bioset_free(md->bs);
1835 * There's no need to reload with request-based dm
1836 * because the size of front_pad doesn't change.
1837 * Note for future: If you are to reload bioset,
1838 * prep-ed requests in the queue may refer
1839 * to bio from the old bioset, so you must walk
1840 * through the queue to unprep.
1845 BUG_ON(!p || md->io_pool || md->bs);
1847 md->io_pool = p->io_pool;
1853 /* mempool bind completed, no longer need any mempools in the table */
1854 dm_table_free_md_mempools(t);
1858 * Bind a table to the device.
1860 static void event_callback(void *context)
1862 unsigned long flags;
1864 struct mapped_device *md = (struct mapped_device *) context;
1866 spin_lock_irqsave(&md->uevent_lock, flags);
1867 list_splice_init(&md->uevent_list, &uevents);
1868 spin_unlock_irqrestore(&md->uevent_lock, flags);
1870 dm_send_uevents(&uevents, &disk_to_dev(md->disk)->kobj);
1872 atomic_inc(&md->event_nr);
1873 wake_up(&md->eventq);
1874 dm_issue_global_event();
1878 * Protected by md->suspend_lock obtained by dm_swap_table().
1880 static void __set_size(struct mapped_device *md, sector_t size)
1882 lockdep_assert_held(&md->suspend_lock);
1884 set_capacity(md->disk, size);
1886 i_size_write(md->bdev->bd_inode, (loff_t)size << SECTOR_SHIFT);
1890 * Returns old map, which caller must destroy.
1892 static struct dm_table *__bind(struct mapped_device *md, struct dm_table *t,
1893 struct queue_limits *limits)
1895 struct dm_table *old_map;
1896 struct request_queue *q = md->queue;
1899 lockdep_assert_held(&md->suspend_lock);
1901 size = dm_table_get_size(t);
1904 * Wipe any geometry if the size of the table changed.
1906 if (size != dm_get_size(md))
1907 memset(&md->geometry, 0, sizeof(md->geometry));
1909 __set_size(md, size);
1911 dm_table_event_callback(t, event_callback, md);
1914 * The queue hasn't been stopped yet, if the old table type wasn't
1915 * for request-based during suspension. So stop it to prevent
1916 * I/O mapping before resume.
1917 * This must be done before setting the queue restrictions,
1918 * because request-based dm may be run just after the setting.
1920 if (dm_table_request_based(t)) {
1923 * Leverage the fact that request-based DM targets are
1924 * immutable singletons and establish md->immutable_target
1925 * - used to optimize both dm_request_fn and dm_mq_queue_rq
1927 md->immutable_target = dm_table_get_immutable_target(t);
1930 __bind_mempools(md, t);
1932 old_map = rcu_dereference_protected(md->map, lockdep_is_held(&md->suspend_lock));
1933 rcu_assign_pointer(md->map, (void *)t);
1934 md->immutable_target_type = dm_table_get_immutable_target_type(t);
1936 dm_table_set_restrictions(t, q, limits);
1944 * Returns unbound table for the caller to free.
1946 static struct dm_table *__unbind(struct mapped_device *md)
1948 struct dm_table *map = rcu_dereference_protected(md->map, 1);
1953 dm_table_event_callback(map, NULL, NULL);
1954 RCU_INIT_POINTER(md->map, NULL);
1961 * Constructor for a new device.
1963 int dm_create(int minor, struct mapped_device **result)
1965 struct mapped_device *md;
1967 md = alloc_dev(minor);
1978 * Functions to manage md->type.
1979 * All are required to hold md->type_lock.
1981 void dm_lock_md_type(struct mapped_device *md)
1983 mutex_lock(&md->type_lock);
1986 void dm_unlock_md_type(struct mapped_device *md)
1988 mutex_unlock(&md->type_lock);
1991 void dm_set_md_type(struct mapped_device *md, enum dm_queue_mode type)
1993 BUG_ON(!mutex_is_locked(&md->type_lock));
1997 enum dm_queue_mode dm_get_md_type(struct mapped_device *md)
2002 struct target_type *dm_get_immutable_target_type(struct mapped_device *md)
2004 return md->immutable_target_type;
2008 * The queue_limits are only valid as long as you have a reference
2011 struct queue_limits *dm_get_queue_limits(struct mapped_device *md)
2013 BUG_ON(!atomic_read(&md->holders));
2014 return &md->queue->limits;
2016 EXPORT_SYMBOL_GPL(dm_get_queue_limits);
2019 * Setup the DM device's queue based on md's type
2021 int dm_setup_md_queue(struct mapped_device *md, struct dm_table *t)
2024 enum dm_queue_mode type = dm_get_md_type(md);
2027 case DM_TYPE_REQUEST_BASED:
2028 r = dm_old_init_request_queue(md, t);
2030 DMERR("Cannot initialize queue for request-based mapped device");
2034 case DM_TYPE_MQ_REQUEST_BASED:
2035 r = dm_mq_init_request_queue(md, t);
2037 DMERR("Cannot initialize queue for request-based dm-mq mapped device");
2041 case DM_TYPE_BIO_BASED:
2042 case DM_TYPE_DAX_BIO_BASED:
2043 dm_init_normal_md_queue(md);
2044 blk_queue_make_request(md->queue, dm_make_request);
2046 * DM handles splitting bios as needed. Free the bio_split bioset
2047 * since it won't be used (saves 1 process per bio-based DM device).
2049 bioset_free(md->queue->bio_split);
2050 md->queue->bio_split = NULL;
2052 if (type == DM_TYPE_DAX_BIO_BASED)
2053 queue_flag_set_unlocked(QUEUE_FLAG_DAX, md->queue);
2063 struct mapped_device *dm_get_md(dev_t dev)
2065 struct mapped_device *md;
2066 unsigned minor = MINOR(dev);
2068 if (MAJOR(dev) != _major || minor >= (1 << MINORBITS))
2071 spin_lock(&_minor_lock);
2073 md = idr_find(&_minor_idr, minor);
2074 if (!md || md == MINOR_ALLOCED || (MINOR(disk_devt(dm_disk(md))) != minor) ||
2075 test_bit(DMF_FREEING, &md->flags) || dm_deleting_md(md)) {
2081 spin_unlock(&_minor_lock);
2085 EXPORT_SYMBOL_GPL(dm_get_md);
2087 void *dm_get_mdptr(struct mapped_device *md)
2089 return md->interface_ptr;
2092 void dm_set_mdptr(struct mapped_device *md, void *ptr)
2094 md->interface_ptr = ptr;
2097 void dm_get(struct mapped_device *md)
2099 atomic_inc(&md->holders);
2100 BUG_ON(test_bit(DMF_FREEING, &md->flags));
2103 int dm_hold(struct mapped_device *md)
2105 spin_lock(&_minor_lock);
2106 if (test_bit(DMF_FREEING, &md->flags)) {
2107 spin_unlock(&_minor_lock);
2111 spin_unlock(&_minor_lock);
2114 EXPORT_SYMBOL_GPL(dm_hold);
2116 const char *dm_device_name(struct mapped_device *md)
2120 EXPORT_SYMBOL_GPL(dm_device_name);
2122 static void __dm_destroy(struct mapped_device *md, bool wait)
2124 struct request_queue *q = dm_get_md_queue(md);
2125 struct dm_table *map;
2130 spin_lock(&_minor_lock);
2131 idr_replace(&_minor_idr, MINOR_ALLOCED, MINOR(disk_devt(dm_disk(md))));
2132 set_bit(DMF_FREEING, &md->flags);
2133 spin_unlock(&_minor_lock);
2135 blk_set_queue_dying(q);
2137 if (dm_request_based(md) && md->kworker_task)
2138 kthread_flush_worker(&md->kworker);
2141 * Take suspend_lock so that presuspend and postsuspend methods
2142 * do not race with internal suspend.
2144 mutex_lock(&md->suspend_lock);
2145 map = dm_get_live_table(md, &srcu_idx);
2146 if (!dm_suspended_md(md)) {
2147 dm_table_presuspend_targets(map);
2148 dm_table_postsuspend_targets(map);
2150 /* dm_put_live_table must be before msleep, otherwise deadlock is possible */
2151 dm_put_live_table(md, srcu_idx);
2152 mutex_unlock(&md->suspend_lock);
2155 * Rare, but there may be I/O requests still going to complete,
2156 * for example. Wait for all references to disappear.
2157 * No one should increment the reference count of the mapped_device,
2158 * after the mapped_device state becomes DMF_FREEING.
2161 while (atomic_read(&md->holders))
2163 else if (atomic_read(&md->holders))
2164 DMWARN("%s: Forcibly removing mapped_device still in use! (%d users)",
2165 dm_device_name(md), atomic_read(&md->holders));
2168 dm_table_destroy(__unbind(md));
2172 void dm_destroy(struct mapped_device *md)
2174 __dm_destroy(md, true);
2177 void dm_destroy_immediate(struct mapped_device *md)
2179 __dm_destroy(md, false);
2182 void dm_put(struct mapped_device *md)
2184 atomic_dec(&md->holders);
2186 EXPORT_SYMBOL_GPL(dm_put);
2188 static int dm_wait_for_completion(struct mapped_device *md, long task_state)
2194 prepare_to_wait(&md->wait, &wait, task_state);
2196 if (!md_in_flight(md))
2199 if (signal_pending_state(task_state, current)) {
2206 finish_wait(&md->wait, &wait);
2212 * Process the deferred bios
2214 static void dm_wq_work(struct work_struct *work)
2216 struct mapped_device *md = container_of(work, struct mapped_device,
2220 struct dm_table *map;
2222 map = dm_get_live_table(md, &srcu_idx);
2224 while (!test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags)) {
2225 spin_lock_irq(&md->deferred_lock);
2226 c = bio_list_pop(&md->deferred);
2227 spin_unlock_irq(&md->deferred_lock);
2232 if (dm_request_based(md))
2233 generic_make_request(c);
2235 __split_and_process_bio(md, map, c);
2238 dm_put_live_table(md, srcu_idx);
2241 static void dm_queue_flush(struct mapped_device *md)
2243 clear_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags);
2244 smp_mb__after_atomic();
2245 queue_work(md->wq, &md->work);
2249 * Swap in a new table, returning the old one for the caller to destroy.
2251 struct dm_table *dm_swap_table(struct mapped_device *md, struct dm_table *table)
2253 struct dm_table *live_map = NULL, *map = ERR_PTR(-EINVAL);
2254 struct queue_limits limits;
2257 mutex_lock(&md->suspend_lock);
2259 /* device must be suspended */
2260 if (!dm_suspended_md(md))
2264 * If the new table has no data devices, retain the existing limits.
2265 * This helps multipath with queue_if_no_path if all paths disappear,
2266 * then new I/O is queued based on these limits, and then some paths
2269 if (dm_table_has_no_data_devices(table)) {
2270 live_map = dm_get_live_table_fast(md);
2272 limits = md->queue->limits;
2273 dm_put_live_table_fast(md);
2277 r = dm_calculate_queue_limits(table, &limits);
2284 map = __bind(md, table, &limits);
2285 dm_issue_global_event();
2288 mutex_unlock(&md->suspend_lock);
2293 * Functions to lock and unlock any filesystem running on the
2296 static int lock_fs(struct mapped_device *md)
2300 WARN_ON(md->frozen_sb);
2302 md->frozen_sb = freeze_bdev(md->bdev);
2303 if (IS_ERR(md->frozen_sb)) {
2304 r = PTR_ERR(md->frozen_sb);
2305 md->frozen_sb = NULL;
2309 set_bit(DMF_FROZEN, &md->flags);
2314 static void unlock_fs(struct mapped_device *md)
2316 if (!test_bit(DMF_FROZEN, &md->flags))
2319 thaw_bdev(md->bdev, md->frozen_sb);
2320 md->frozen_sb = NULL;
2321 clear_bit(DMF_FROZEN, &md->flags);
2325 * @suspend_flags: DM_SUSPEND_LOCKFS_FLAG and/or DM_SUSPEND_NOFLUSH_FLAG
2326 * @task_state: e.g. TASK_INTERRUPTIBLE or TASK_UNINTERRUPTIBLE
2327 * @dmf_suspended_flag: DMF_SUSPENDED or DMF_SUSPENDED_INTERNALLY
2329 * If __dm_suspend returns 0, the device is completely quiescent
2330 * now. There is no request-processing activity. All new requests
2331 * are being added to md->deferred list.
2333 static int __dm_suspend(struct mapped_device *md, struct dm_table *map,
2334 unsigned suspend_flags, long task_state,
2335 int dmf_suspended_flag)
2337 bool do_lockfs = suspend_flags & DM_SUSPEND_LOCKFS_FLAG;
2338 bool noflush = suspend_flags & DM_SUSPEND_NOFLUSH_FLAG;
2341 lockdep_assert_held(&md->suspend_lock);
2344 * DMF_NOFLUSH_SUSPENDING must be set before presuspend.
2345 * This flag is cleared before dm_suspend returns.
2348 set_bit(DMF_NOFLUSH_SUSPENDING, &md->flags);
2350 pr_debug("%s: suspending with flush\n", dm_device_name(md));
2353 * This gets reverted if there's an error later and the targets
2354 * provide the .presuspend_undo hook.
2356 dm_table_presuspend_targets(map);
2359 * Flush I/O to the device.
2360 * Any I/O submitted after lock_fs() may not be flushed.
2361 * noflush takes precedence over do_lockfs.
2362 * (lock_fs() flushes I/Os and waits for them to complete.)
2364 if (!noflush && do_lockfs) {
2367 dm_table_presuspend_undo_targets(map);
2373 * Here we must make sure that no processes are submitting requests
2374 * to target drivers i.e. no one may be executing
2375 * __split_and_process_bio. This is called from dm_request and
2378 * To get all processes out of __split_and_process_bio in dm_request,
2379 * we take the write lock. To prevent any process from reentering
2380 * __split_and_process_bio from dm_request and quiesce the thread
2381 * (dm_wq_work), we set BMF_BLOCK_IO_FOR_SUSPEND and call
2382 * flush_workqueue(md->wq).
2384 set_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags);
2386 synchronize_srcu(&md->io_barrier);
2389 * Stop md->queue before flushing md->wq in case request-based
2390 * dm defers requests to md->wq from md->queue.
2392 if (dm_request_based(md)) {
2393 dm_stop_queue(md->queue);
2394 if (md->kworker_task)
2395 kthread_flush_worker(&md->kworker);
2398 flush_workqueue(md->wq);
2401 * At this point no more requests are entering target request routines.
2402 * We call dm_wait_for_completion to wait for all existing requests
2405 r = dm_wait_for_completion(md, task_state);
2407 set_bit(dmf_suspended_flag, &md->flags);
2410 clear_bit(DMF_NOFLUSH_SUSPENDING, &md->flags);
2412 synchronize_srcu(&md->io_barrier);
2414 /* were we interrupted ? */
2418 if (dm_request_based(md))
2419 dm_start_queue(md->queue);
2422 dm_table_presuspend_undo_targets(map);
2423 /* pushback list is already flushed, so skip flush */
2430 * We need to be able to change a mapping table under a mounted
2431 * filesystem. For example we might want to move some data in
2432 * the background. Before the table can be swapped with
2433 * dm_bind_table, dm_suspend must be called to flush any in
2434 * flight bios and ensure that any further io gets deferred.
2437 * Suspend mechanism in request-based dm.
2439 * 1. Flush all I/Os by lock_fs() if needed.
2440 * 2. Stop dispatching any I/O by stopping the request_queue.
2441 * 3. Wait for all in-flight I/Os to be completed or requeued.
2443 * To abort suspend, start the request_queue.
2445 int dm_suspend(struct mapped_device *md, unsigned suspend_flags)
2447 struct dm_table *map = NULL;
2451 mutex_lock_nested(&md->suspend_lock, SINGLE_DEPTH_NESTING);
2453 if (dm_suspended_md(md)) {
2458 if (dm_suspended_internally_md(md)) {
2459 /* already internally suspended, wait for internal resume */
2460 mutex_unlock(&md->suspend_lock);
2461 r = wait_on_bit(&md->flags, DMF_SUSPENDED_INTERNALLY, TASK_INTERRUPTIBLE);
2467 map = rcu_dereference_protected(md->map, lockdep_is_held(&md->suspend_lock));
2469 r = __dm_suspend(md, map, suspend_flags, TASK_INTERRUPTIBLE, DMF_SUSPENDED);
2473 dm_table_postsuspend_targets(map);
2476 mutex_unlock(&md->suspend_lock);
2480 static int __dm_resume(struct mapped_device *md, struct dm_table *map)
2483 int r = dm_table_resume_targets(map);
2491 * Flushing deferred I/Os must be done after targets are resumed
2492 * so that mapping of targets can work correctly.
2493 * Request-based dm is queueing the deferred I/Os in its request_queue.
2495 if (dm_request_based(md))
2496 dm_start_queue(md->queue);
2503 int dm_resume(struct mapped_device *md)
2506 struct dm_table *map = NULL;
2510 mutex_lock_nested(&md->suspend_lock, SINGLE_DEPTH_NESTING);
2512 if (!dm_suspended_md(md))
2515 if (dm_suspended_internally_md(md)) {
2516 /* already internally suspended, wait for internal resume */
2517 mutex_unlock(&md->suspend_lock);
2518 r = wait_on_bit(&md->flags, DMF_SUSPENDED_INTERNALLY, TASK_INTERRUPTIBLE);
2524 map = rcu_dereference_protected(md->map, lockdep_is_held(&md->suspend_lock));
2525 if (!map || !dm_table_get_size(map))
2528 r = __dm_resume(md, map);
2532 clear_bit(DMF_SUSPENDED, &md->flags);
2534 mutex_unlock(&md->suspend_lock);
2540 * Internal suspend/resume works like userspace-driven suspend. It waits
2541 * until all bios finish and prevents issuing new bios to the target drivers.
2542 * It may be used only from the kernel.
2545 static void __dm_internal_suspend(struct mapped_device *md, unsigned suspend_flags)
2547 struct dm_table *map = NULL;
2549 lockdep_assert_held(&md->suspend_lock);
2551 if (md->internal_suspend_count++)
2552 return; /* nested internal suspend */
2554 if (dm_suspended_md(md)) {
2555 set_bit(DMF_SUSPENDED_INTERNALLY, &md->flags);
2556 return; /* nest suspend */
2559 map = rcu_dereference_protected(md->map, lockdep_is_held(&md->suspend_lock));
2562 * Using TASK_UNINTERRUPTIBLE because only NOFLUSH internal suspend is
2563 * supported. Properly supporting a TASK_INTERRUPTIBLE internal suspend
2564 * would require changing .presuspend to return an error -- avoid this
2565 * until there is a need for more elaborate variants of internal suspend.
2567 (void) __dm_suspend(md, map, suspend_flags, TASK_UNINTERRUPTIBLE,
2568 DMF_SUSPENDED_INTERNALLY);
2570 dm_table_postsuspend_targets(map);
2573 static void __dm_internal_resume(struct mapped_device *md)
2575 BUG_ON(!md->internal_suspend_count);
2577 if (--md->internal_suspend_count)
2578 return; /* resume from nested internal suspend */
2580 if (dm_suspended_md(md))
2581 goto done; /* resume from nested suspend */
2584 * NOTE: existing callers don't need to call dm_table_resume_targets
2585 * (which may fail -- so best to avoid it for now by passing NULL map)
2587 (void) __dm_resume(md, NULL);
2590 clear_bit(DMF_SUSPENDED_INTERNALLY, &md->flags);
2591 smp_mb__after_atomic();
2592 wake_up_bit(&md->flags, DMF_SUSPENDED_INTERNALLY);
2595 void dm_internal_suspend_noflush(struct mapped_device *md)
2597 mutex_lock(&md->suspend_lock);
2598 __dm_internal_suspend(md, DM_SUSPEND_NOFLUSH_FLAG);
2599 mutex_unlock(&md->suspend_lock);
2601 EXPORT_SYMBOL_GPL(dm_internal_suspend_noflush);
2603 void dm_internal_resume(struct mapped_device *md)
2605 mutex_lock(&md->suspend_lock);
2606 __dm_internal_resume(md);
2607 mutex_unlock(&md->suspend_lock);
2609 EXPORT_SYMBOL_GPL(dm_internal_resume);
2612 * Fast variants of internal suspend/resume hold md->suspend_lock,
2613 * which prevents interaction with userspace-driven suspend.
2616 void dm_internal_suspend_fast(struct mapped_device *md)
2618 mutex_lock(&md->suspend_lock);
2619 if (dm_suspended_md(md) || dm_suspended_internally_md(md))
2622 set_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags);
2623 synchronize_srcu(&md->io_barrier);
2624 flush_workqueue(md->wq);
2625 dm_wait_for_completion(md, TASK_UNINTERRUPTIBLE);
2627 EXPORT_SYMBOL_GPL(dm_internal_suspend_fast);
2629 void dm_internal_resume_fast(struct mapped_device *md)
2631 if (dm_suspended_md(md) || dm_suspended_internally_md(md))
2637 mutex_unlock(&md->suspend_lock);
2639 EXPORT_SYMBOL_GPL(dm_internal_resume_fast);
2641 /*-----------------------------------------------------------------
2642 * Event notification.
2643 *---------------------------------------------------------------*/
2644 int dm_kobject_uevent(struct mapped_device *md, enum kobject_action action,
2647 char udev_cookie[DM_COOKIE_LENGTH];
2648 char *envp[] = { udev_cookie, NULL };
2651 return kobject_uevent(&disk_to_dev(md->disk)->kobj, action);
2653 snprintf(udev_cookie, DM_COOKIE_LENGTH, "%s=%u",
2654 DM_COOKIE_ENV_VAR_NAME, cookie);
2655 return kobject_uevent_env(&disk_to_dev(md->disk)->kobj,
2660 uint32_t dm_next_uevent_seq(struct mapped_device *md)
2662 return atomic_add_return(1, &md->uevent_seq);
2665 uint32_t dm_get_event_nr(struct mapped_device *md)
2667 return atomic_read(&md->event_nr);
2670 int dm_wait_event(struct mapped_device *md, int event_nr)
2672 return wait_event_interruptible(md->eventq,
2673 (event_nr != atomic_read(&md->event_nr)));
2676 void dm_uevent_add(struct mapped_device *md, struct list_head *elist)
2678 unsigned long flags;
2680 spin_lock_irqsave(&md->uevent_lock, flags);
2681 list_add(elist, &md->uevent_list);
2682 spin_unlock_irqrestore(&md->uevent_lock, flags);
2686 * The gendisk is only valid as long as you have a reference
2689 struct gendisk *dm_disk(struct mapped_device *md)
2693 EXPORT_SYMBOL_GPL(dm_disk);
2695 struct kobject *dm_kobject(struct mapped_device *md)
2697 return &md->kobj_holder.kobj;
2700 struct mapped_device *dm_get_from_kobject(struct kobject *kobj)
2702 struct mapped_device *md;
2704 md = container_of(kobj, struct mapped_device, kobj_holder.kobj);
2706 spin_lock(&_minor_lock);
2707 if (test_bit(DMF_FREEING, &md->flags) || dm_deleting_md(md)) {
2713 spin_unlock(&_minor_lock);
2718 int dm_suspended_md(struct mapped_device *md)
2720 return test_bit(DMF_SUSPENDED, &md->flags);
2723 int dm_suspended_internally_md(struct mapped_device *md)
2725 return test_bit(DMF_SUSPENDED_INTERNALLY, &md->flags);
2728 int dm_test_deferred_remove_flag(struct mapped_device *md)
2730 return test_bit(DMF_DEFERRED_REMOVE, &md->flags);
2733 int dm_suspended(struct dm_target *ti)
2735 return dm_suspended_md(dm_table_get_md(ti->table));
2737 EXPORT_SYMBOL_GPL(dm_suspended);
2739 int dm_noflush_suspending(struct dm_target *ti)
2741 return __noflush_suspending(dm_table_get_md(ti->table));
2743 EXPORT_SYMBOL_GPL(dm_noflush_suspending);
2745 struct dm_md_mempools *dm_alloc_md_mempools(struct mapped_device *md, enum dm_queue_mode type,
2746 unsigned integrity, unsigned per_io_data_size)
2748 struct dm_md_mempools *pools = kzalloc_node(sizeof(*pools), GFP_KERNEL, md->numa_node_id);
2749 unsigned int pool_size = 0;
2750 unsigned int front_pad;
2756 case DM_TYPE_BIO_BASED:
2757 case DM_TYPE_DAX_BIO_BASED:
2758 pool_size = dm_get_reserved_bio_based_ios();
2759 front_pad = roundup(per_io_data_size, __alignof__(struct dm_target_io)) + offsetof(struct dm_target_io, clone);
2761 pools->io_pool = mempool_create_slab_pool(pool_size, _io_cache);
2762 if (!pools->io_pool)
2765 case DM_TYPE_REQUEST_BASED:
2766 case DM_TYPE_MQ_REQUEST_BASED:
2767 pool_size = dm_get_reserved_rq_based_ios();
2768 front_pad = offsetof(struct dm_rq_clone_bio_info, clone);
2769 /* per_io_data_size is used for blk-mq pdu at queue allocation */
2775 pools->bs = bioset_create(pool_size, front_pad, BIOSET_NEED_RESCUER);
2779 if (integrity && bioset_integrity_create(pools->bs, pool_size))
2785 dm_free_md_mempools(pools);
2790 void dm_free_md_mempools(struct dm_md_mempools *pools)
2795 mempool_destroy(pools->io_pool);
2798 bioset_free(pools->bs);
2810 static int dm_call_pr(struct block_device *bdev, iterate_devices_callout_fn fn,
2813 struct mapped_device *md = bdev->bd_disk->private_data;
2814 struct dm_table *table;
2815 struct dm_target *ti;
2816 int ret = -ENOTTY, srcu_idx;
2818 table = dm_get_live_table(md, &srcu_idx);
2819 if (!table || !dm_table_get_size(table))
2822 /* We only support devices that have a single target */
2823 if (dm_table_get_num_targets(table) != 1)
2825 ti = dm_table_get_target(table, 0);
2828 if (!ti->type->iterate_devices)
2831 ret = ti->type->iterate_devices(ti, fn, data);
2833 dm_put_live_table(md, srcu_idx);
2838 * For register / unregister we need to manually call out to every path.
2840 static int __dm_pr_register(struct dm_target *ti, struct dm_dev *dev,
2841 sector_t start, sector_t len, void *data)
2843 struct dm_pr *pr = data;
2844 const struct pr_ops *ops = dev->bdev->bd_disk->fops->pr_ops;
2846 if (!ops || !ops->pr_register)
2848 return ops->pr_register(dev->bdev, pr->old_key, pr->new_key, pr->flags);
2851 static int dm_pr_register(struct block_device *bdev, u64 old_key, u64 new_key,
2862 ret = dm_call_pr(bdev, __dm_pr_register, &pr);
2863 if (ret && new_key) {
2864 /* unregister all paths if we failed to register any path */
2865 pr.old_key = new_key;
2868 pr.fail_early = false;
2869 dm_call_pr(bdev, __dm_pr_register, &pr);
2875 static int dm_pr_reserve(struct block_device *bdev, u64 key, enum pr_type type,
2878 struct mapped_device *md = bdev->bd_disk->private_data;
2879 const struct pr_ops *ops;
2883 r = dm_grab_bdev_for_ioctl(md, &bdev, &mode);
2887 ops = bdev->bd_disk->fops->pr_ops;
2888 if (ops && ops->pr_reserve)
2889 r = ops->pr_reserve(bdev, key, type, flags);
2897 static int dm_pr_release(struct block_device *bdev, u64 key, enum pr_type type)
2899 struct mapped_device *md = bdev->bd_disk->private_data;
2900 const struct pr_ops *ops;
2904 r = dm_grab_bdev_for_ioctl(md, &bdev, &mode);
2908 ops = bdev->bd_disk->fops->pr_ops;
2909 if (ops && ops->pr_release)
2910 r = ops->pr_release(bdev, key, type);
2918 static int dm_pr_preempt(struct block_device *bdev, u64 old_key, u64 new_key,
2919 enum pr_type type, bool abort)
2921 struct mapped_device *md = bdev->bd_disk->private_data;
2922 const struct pr_ops *ops;
2926 r = dm_grab_bdev_for_ioctl(md, &bdev, &mode);
2930 ops = bdev->bd_disk->fops->pr_ops;
2931 if (ops && ops->pr_preempt)
2932 r = ops->pr_preempt(bdev, old_key, new_key, type, abort);
2940 static int dm_pr_clear(struct block_device *bdev, u64 key)
2942 struct mapped_device *md = bdev->bd_disk->private_data;
2943 const struct pr_ops *ops;
2947 r = dm_grab_bdev_for_ioctl(md, &bdev, &mode);
2951 ops = bdev->bd_disk->fops->pr_ops;
2952 if (ops && ops->pr_clear)
2953 r = ops->pr_clear(bdev, key);
2961 static const struct pr_ops dm_pr_ops = {
2962 .pr_register = dm_pr_register,
2963 .pr_reserve = dm_pr_reserve,
2964 .pr_release = dm_pr_release,
2965 .pr_preempt = dm_pr_preempt,
2966 .pr_clear = dm_pr_clear,
2969 static const struct block_device_operations dm_blk_dops = {
2970 .open = dm_blk_open,
2971 .release = dm_blk_close,
2972 .ioctl = dm_blk_ioctl,
2973 .getgeo = dm_blk_getgeo,
2974 .pr_ops = &dm_pr_ops,
2975 .owner = THIS_MODULE
2978 static const struct dax_operations dm_dax_ops = {
2979 .direct_access = dm_dax_direct_access,
2980 .copy_from_iter = dm_dax_copy_from_iter,
2986 module_init(dm_init);
2987 module_exit(dm_exit);
2989 module_param(major, uint, 0);
2990 MODULE_PARM_DESC(major, "The major number of the device mapper");
2992 module_param(reserved_bio_based_ios, uint, S_IRUGO | S_IWUSR);
2993 MODULE_PARM_DESC(reserved_bio_based_ios, "Reserved IOs in bio-based mempools");
2995 module_param(dm_numa_node, int, S_IRUGO | S_IWUSR);
2996 MODULE_PARM_DESC(dm_numa_node, "NUMA node for DM device memory allocations");
2998 MODULE_DESCRIPTION(DM_NAME " driver");
2999 MODULE_AUTHOR("Joe Thornber <dm-devel@redhat.com>");
3000 MODULE_LICENSE("GPL");