1 // SPDX-License-Identifier: GPL-2.0-only
3 * Copyright (C) 2011-2012 Red Hat, Inc.
5 * This file is released under the GPL.
8 #include "dm-thin-metadata.h"
9 #include "persistent-data/dm-btree.h"
10 #include "persistent-data/dm-space-map.h"
11 #include "persistent-data/dm-space-map-disk.h"
12 #include "persistent-data/dm-transaction-manager.h"
14 #include <linux/list.h>
15 #include <linux/device-mapper.h>
16 #include <linux/workqueue.h>
19 *--------------------------------------------------------------------------
20 * As far as the metadata goes, there is:
22 * - A superblock in block zero, taking up fewer than 512 bytes for
25 * - A space map managing the metadata blocks.
27 * - A space map managing the data blocks.
29 * - A btree mapping our internal thin dev ids onto struct disk_device_details.
31 * - A hierarchical btree, with 2 levels which effectively maps (thin
32 * dev id, virtual block) -> block_time. Block time is a 64-bit
33 * field holding the time in the low 24 bits, and block in the top 40
36 * BTrees consist solely of btree_nodes, that fill a block. Some are
37 * internal nodes, as such their values are a __le64 pointing to other
38 * nodes. Leaf nodes can store data of any reasonable size (ie. much
39 * smaller than the block size). The nodes consist of the header,
40 * followed by an array of keys, followed by an array of values. We have
41 * to binary search on the keys so they're all held together to help the
44 * Space maps have 2 btrees:
46 * - One maps a uint64_t onto a struct index_entry. Which points to a
47 * bitmap block, and has some details about how many free entries there
50 * - The bitmap blocks have a header (for the checksum). Then the rest
51 * of the block is pairs of bits. With the meaning being:
56 * 3 - ref count is higher than 2
58 * - If the count is higher than 2 then the ref count is entered in a
59 * second btree that directly maps the block_address to a uint32_t ref
62 * The space map metadata variant doesn't have a bitmaps btree. Instead
63 * it has one single blocks worth of index_entries. This avoids
64 * recursive issues with the bitmap btree needing to allocate space in
65 * order to insert. With a small data block size such as 64k the
66 * metadata support data devices that are hundreds of terrabytes.
68 * The space maps allocate space linearly from front to back. Space that
69 * is freed in a transaction is never recycled within that transaction.
70 * To try and avoid fragmenting _free_ space the allocator always goes
71 * back and fills in gaps.
73 * All metadata io is in THIN_METADATA_BLOCK_SIZE sized/aligned chunks
74 * from the block manager.
75 *--------------------------------------------------------------------------
78 #define DM_MSG_PREFIX "thin metadata"
80 #define THIN_SUPERBLOCK_MAGIC 27022010
81 #define THIN_SUPERBLOCK_LOCATION 0
82 #define THIN_VERSION 2
83 #define SECTOR_TO_BLOCK_SHIFT 3
87 * 3 for btree insert +
88 * 2 for btree lookup used within space map
90 * 2 for shadow spine +
91 * 4 for rebalance 3 child node
93 #define THIN_MAX_CONCURRENT_LOCKS 6
95 /* This should be plenty */
96 #define SPACE_MAP_ROOT_SIZE 128
99 * Little endian on-disk superblock and device details.
101 struct thin_disk_superblock {
102 __le32 csum; /* Checksum of superblock except for this field. */
104 __le64 blocknr; /* This block number, dm_block_t. */
114 * Root held by userspace transactions.
118 __u8 data_space_map_root[SPACE_MAP_ROOT_SIZE];
119 __u8 metadata_space_map_root[SPACE_MAP_ROOT_SIZE];
122 * 2-level btree mapping (dev_id, (dev block, time)) -> data block
124 __le64 data_mapping_root;
127 * Device detail root mapping dev_id -> device_details
129 __le64 device_details_root;
131 __le32 data_block_size; /* In 512-byte sectors. */
133 __le32 metadata_block_size; /* In 512-byte sectors. */
134 __le64 metadata_nr_blocks;
137 __le32 compat_ro_flags;
138 __le32 incompat_flags;
141 struct disk_device_details {
142 __le64 mapped_blocks;
143 __le64 transaction_id; /* When created. */
144 __le32 creation_time;
145 __le32 snapshotted_time;
148 struct dm_pool_metadata {
149 struct hlist_node hash;
151 struct block_device *bdev;
152 struct dm_block_manager *bm;
153 struct dm_space_map *metadata_sm;
154 struct dm_space_map *data_sm;
155 struct dm_transaction_manager *tm;
156 struct dm_transaction_manager *nb_tm;
160 * First level holds thin_dev_t.
161 * Second level holds mappings.
163 struct dm_btree_info info;
166 * Non-blocking version of the above.
168 struct dm_btree_info nb_info;
171 * Just the top level for deleting whole devices.
173 struct dm_btree_info tl_info;
176 * Just the bottom level for creating new devices.
178 struct dm_btree_info bl_info;
181 * Describes the device details btree.
183 struct dm_btree_info details_info;
185 struct rw_semaphore root_lock;
188 dm_block_t details_root;
189 struct list_head thin_devices;
192 sector_t data_block_size;
195 * Pre-commit callback.
197 * This allows the thin provisioning target to run a callback before
198 * the metadata are committed.
200 dm_pool_pre_commit_fn pre_commit_fn;
201 void *pre_commit_context;
204 * We reserve a section of the metadata for commit overhead.
205 * All reported space does *not* include this.
207 dm_block_t metadata_reserve;
210 * Set if a transaction has to be aborted but the attempt to roll back
211 * to the previous (good) transaction failed. The only pool metadata
212 * operation possible in this state is the closing of the device.
217 * Set once a thin-pool has been accessed through one of the interfaces
218 * that imply the pool is in-service (e.g. thin devices created/deleted,
219 * thin-pool message, metadata snapshots, etc).
224 * Reading the space map roots can fail, so we read it into these
225 * buffers before the superblock is locked and updated.
227 __u8 data_space_map_root[SPACE_MAP_ROOT_SIZE];
228 __u8 metadata_space_map_root[SPACE_MAP_ROOT_SIZE];
231 struct dm_thin_device {
232 struct list_head list;
233 struct dm_pool_metadata *pmd;
238 bool aborted_with_changes:1;
239 uint64_t mapped_blocks;
240 uint64_t transaction_id;
241 uint32_t creation_time;
242 uint32_t snapshotted_time;
246 *--------------------------------------------------------------
247 * superblock validator
248 *--------------------------------------------------------------
250 #define SUPERBLOCK_CSUM_XOR 160774
252 static void sb_prepare_for_write(struct dm_block_validator *v,
256 struct thin_disk_superblock *disk_super = dm_block_data(b);
258 disk_super->blocknr = cpu_to_le64(dm_block_location(b));
259 disk_super->csum = cpu_to_le32(dm_bm_checksum(&disk_super->flags,
260 block_size - sizeof(__le32),
261 SUPERBLOCK_CSUM_XOR));
264 static int sb_check(struct dm_block_validator *v,
268 struct thin_disk_superblock *disk_super = dm_block_data(b);
271 if (dm_block_location(b) != le64_to_cpu(disk_super->blocknr)) {
272 DMERR("%s failed: blocknr %llu: wanted %llu",
273 __func__, le64_to_cpu(disk_super->blocknr),
274 (unsigned long long)dm_block_location(b));
278 if (le64_to_cpu(disk_super->magic) != THIN_SUPERBLOCK_MAGIC) {
279 DMERR("%s failed: magic %llu: wanted %llu",
280 __func__, le64_to_cpu(disk_super->magic),
281 (unsigned long long)THIN_SUPERBLOCK_MAGIC);
285 csum_le = cpu_to_le32(dm_bm_checksum(&disk_super->flags,
286 block_size - sizeof(__le32),
287 SUPERBLOCK_CSUM_XOR));
288 if (csum_le != disk_super->csum) {
289 DMERR("%s failed: csum %u: wanted %u",
290 __func__, le32_to_cpu(csum_le), le32_to_cpu(disk_super->csum));
297 static struct dm_block_validator sb_validator = {
298 .name = "superblock",
299 .prepare_for_write = sb_prepare_for_write,
304 *--------------------------------------------------------------
305 * Methods for the btree value types
306 *--------------------------------------------------------------
308 static uint64_t pack_block_time(dm_block_t b, uint32_t t)
310 return (b << 24) | t;
313 static void unpack_block_time(uint64_t v, dm_block_t *b, uint32_t *t)
316 *t = v & ((1 << 24) - 1);
320 * It's more efficient to call dm_sm_{inc,dec}_blocks as few times as
321 * possible. 'with_runs' reads contiguous runs of blocks, and calls the
324 typedef int (*run_fn)(struct dm_space_map *, dm_block_t, dm_block_t);
326 static void with_runs(struct dm_space_map *sm, const __le64 *value_le, unsigned int count, run_fn fn)
328 uint64_t b, begin, end;
333 for (i = 0; i < count; i++, value_le++) {
334 /* We know value_le is 8 byte aligned */
335 unpack_block_time(le64_to_cpu(*value_le), &b, &t);
356 static void data_block_inc(void *context, const void *value_le, unsigned int count)
358 with_runs((struct dm_space_map *) context,
359 (const __le64 *) value_le, count, dm_sm_inc_blocks);
362 static void data_block_dec(void *context, const void *value_le, unsigned int count)
364 with_runs((struct dm_space_map *) context,
365 (const __le64 *) value_le, count, dm_sm_dec_blocks);
368 static int data_block_equal(void *context, const void *value1_le, const void *value2_le)
374 memcpy(&v1_le, value1_le, sizeof(v1_le));
375 memcpy(&v2_le, value2_le, sizeof(v2_le));
376 unpack_block_time(le64_to_cpu(v1_le), &b1, &t);
377 unpack_block_time(le64_to_cpu(v2_le), &b2, &t);
382 static void subtree_inc(void *context, const void *value, unsigned int count)
384 struct dm_btree_info *info = context;
385 const __le64 *root_le = value;
388 for (i = 0; i < count; i++, root_le++)
389 dm_tm_inc(info->tm, le64_to_cpu(*root_le));
392 static void subtree_dec(void *context, const void *value, unsigned int count)
394 struct dm_btree_info *info = context;
395 const __le64 *root_le = value;
398 for (i = 0; i < count; i++, root_le++)
399 if (dm_btree_del(info, le64_to_cpu(*root_le)))
400 DMERR("btree delete failed");
403 static int subtree_equal(void *context, const void *value1_le, const void *value2_le)
407 memcpy(&v1_le, value1_le, sizeof(v1_le));
408 memcpy(&v2_le, value2_le, sizeof(v2_le));
410 return v1_le == v2_le;
413 /*----------------------------------------------------------------*/
416 * Variant that is used for in-core only changes or code that
417 * shouldn't put the pool in service on its own (e.g. commit).
419 static inline void pmd_write_lock_in_core(struct dm_pool_metadata *pmd)
420 __acquires(pmd->root_lock)
422 down_write(&pmd->root_lock);
425 static inline void pmd_write_lock(struct dm_pool_metadata *pmd)
427 pmd_write_lock_in_core(pmd);
428 if (unlikely(!pmd->in_service))
429 pmd->in_service = true;
432 static inline void pmd_write_unlock(struct dm_pool_metadata *pmd)
433 __releases(pmd->root_lock)
435 up_write(&pmd->root_lock);
438 /*----------------------------------------------------------------*/
440 static int superblock_lock_zero(struct dm_pool_metadata *pmd,
441 struct dm_block **sblock)
443 return dm_bm_write_lock_zero(pmd->bm, THIN_SUPERBLOCK_LOCATION,
444 &sb_validator, sblock);
447 static int superblock_lock(struct dm_pool_metadata *pmd,
448 struct dm_block **sblock)
450 return dm_bm_write_lock(pmd->bm, THIN_SUPERBLOCK_LOCATION,
451 &sb_validator, sblock);
454 static int __superblock_all_zeroes(struct dm_block_manager *bm, int *result)
459 __le64 *data_le, zero = cpu_to_le64(0);
460 unsigned int block_size = dm_bm_block_size(bm) / sizeof(__le64);
463 * We can't use a validator here - it may be all zeroes.
465 r = dm_bm_read_lock(bm, THIN_SUPERBLOCK_LOCATION, NULL, &b);
469 data_le = dm_block_data(b);
471 for (i = 0; i < block_size; i++) {
472 if (data_le[i] != zero) {
483 static void __setup_btree_details(struct dm_pool_metadata *pmd)
485 pmd->info.tm = pmd->tm;
486 pmd->info.levels = 2;
487 pmd->info.value_type.context = pmd->data_sm;
488 pmd->info.value_type.size = sizeof(__le64);
489 pmd->info.value_type.inc = data_block_inc;
490 pmd->info.value_type.dec = data_block_dec;
491 pmd->info.value_type.equal = data_block_equal;
493 memcpy(&pmd->nb_info, &pmd->info, sizeof(pmd->nb_info));
494 pmd->nb_info.tm = pmd->nb_tm;
496 pmd->tl_info.tm = pmd->tm;
497 pmd->tl_info.levels = 1;
498 pmd->tl_info.value_type.context = &pmd->bl_info;
499 pmd->tl_info.value_type.size = sizeof(__le64);
500 pmd->tl_info.value_type.inc = subtree_inc;
501 pmd->tl_info.value_type.dec = subtree_dec;
502 pmd->tl_info.value_type.equal = subtree_equal;
504 pmd->bl_info.tm = pmd->tm;
505 pmd->bl_info.levels = 1;
506 pmd->bl_info.value_type.context = pmd->data_sm;
507 pmd->bl_info.value_type.size = sizeof(__le64);
508 pmd->bl_info.value_type.inc = data_block_inc;
509 pmd->bl_info.value_type.dec = data_block_dec;
510 pmd->bl_info.value_type.equal = data_block_equal;
512 pmd->details_info.tm = pmd->tm;
513 pmd->details_info.levels = 1;
514 pmd->details_info.value_type.context = NULL;
515 pmd->details_info.value_type.size = sizeof(struct disk_device_details);
516 pmd->details_info.value_type.inc = NULL;
517 pmd->details_info.value_type.dec = NULL;
518 pmd->details_info.value_type.equal = NULL;
521 static int save_sm_roots(struct dm_pool_metadata *pmd)
526 r = dm_sm_root_size(pmd->metadata_sm, &len);
530 r = dm_sm_copy_root(pmd->metadata_sm, &pmd->metadata_space_map_root, len);
534 r = dm_sm_root_size(pmd->data_sm, &len);
538 return dm_sm_copy_root(pmd->data_sm, &pmd->data_space_map_root, len);
541 static void copy_sm_roots(struct dm_pool_metadata *pmd,
542 struct thin_disk_superblock *disk)
544 memcpy(&disk->metadata_space_map_root,
545 &pmd->metadata_space_map_root,
546 sizeof(pmd->metadata_space_map_root));
548 memcpy(&disk->data_space_map_root,
549 &pmd->data_space_map_root,
550 sizeof(pmd->data_space_map_root));
553 static int __write_initial_superblock(struct dm_pool_metadata *pmd)
556 struct dm_block *sblock;
557 struct thin_disk_superblock *disk_super;
558 sector_t bdev_size = bdev_nr_sectors(pmd->bdev);
560 if (bdev_size > THIN_METADATA_MAX_SECTORS)
561 bdev_size = THIN_METADATA_MAX_SECTORS;
563 r = dm_sm_commit(pmd->data_sm);
567 r = dm_tm_pre_commit(pmd->tm);
571 r = save_sm_roots(pmd);
575 r = superblock_lock_zero(pmd, &sblock);
579 disk_super = dm_block_data(sblock);
580 disk_super->flags = 0;
581 memset(disk_super->uuid, 0, sizeof(disk_super->uuid));
582 disk_super->magic = cpu_to_le64(THIN_SUPERBLOCK_MAGIC);
583 disk_super->version = cpu_to_le32(THIN_VERSION);
584 disk_super->time = 0;
585 disk_super->trans_id = 0;
586 disk_super->held_root = 0;
588 copy_sm_roots(pmd, disk_super);
590 disk_super->data_mapping_root = cpu_to_le64(pmd->root);
591 disk_super->device_details_root = cpu_to_le64(pmd->details_root);
592 disk_super->metadata_block_size = cpu_to_le32(THIN_METADATA_BLOCK_SIZE);
593 disk_super->metadata_nr_blocks = cpu_to_le64(bdev_size >> SECTOR_TO_BLOCK_SHIFT);
594 disk_super->data_block_size = cpu_to_le32(pmd->data_block_size);
596 return dm_tm_commit(pmd->tm, sblock);
599 static int __format_metadata(struct dm_pool_metadata *pmd)
603 r = dm_tm_create_with_sm(pmd->bm, THIN_SUPERBLOCK_LOCATION,
604 &pmd->tm, &pmd->metadata_sm);
606 DMERR("tm_create_with_sm failed");
610 pmd->data_sm = dm_sm_disk_create(pmd->tm, 0);
611 if (IS_ERR(pmd->data_sm)) {
612 DMERR("sm_disk_create failed");
613 r = PTR_ERR(pmd->data_sm);
617 pmd->nb_tm = dm_tm_create_non_blocking_clone(pmd->tm);
619 DMERR("could not create non-blocking clone tm");
621 goto bad_cleanup_data_sm;
624 __setup_btree_details(pmd);
626 r = dm_btree_empty(&pmd->info, &pmd->root);
628 goto bad_cleanup_nb_tm;
630 r = dm_btree_empty(&pmd->details_info, &pmd->details_root);
632 DMERR("couldn't create devices root");
633 goto bad_cleanup_nb_tm;
636 r = __write_initial_superblock(pmd);
638 goto bad_cleanup_nb_tm;
643 dm_tm_destroy(pmd->nb_tm);
645 dm_sm_destroy(pmd->data_sm);
647 dm_tm_destroy(pmd->tm);
648 dm_sm_destroy(pmd->metadata_sm);
653 static int __check_incompat_features(struct thin_disk_superblock *disk_super,
654 struct dm_pool_metadata *pmd)
658 features = le32_to_cpu(disk_super->incompat_flags) & ~THIN_FEATURE_INCOMPAT_SUPP;
660 DMERR("could not access metadata due to unsupported optional features (%lx).",
661 (unsigned long)features);
666 * Check for read-only metadata to skip the following RDWR checks.
668 if (bdev_read_only(pmd->bdev))
671 features = le32_to_cpu(disk_super->compat_ro_flags) & ~THIN_FEATURE_COMPAT_RO_SUPP;
673 DMERR("could not access metadata RDWR due to unsupported optional features (%lx).",
674 (unsigned long)features);
681 static int __open_metadata(struct dm_pool_metadata *pmd)
684 struct dm_block *sblock;
685 struct thin_disk_superblock *disk_super;
687 r = dm_bm_read_lock(pmd->bm, THIN_SUPERBLOCK_LOCATION,
688 &sb_validator, &sblock);
690 DMERR("couldn't read superblock");
694 disk_super = dm_block_data(sblock);
696 /* Verify the data block size hasn't changed */
697 if (le32_to_cpu(disk_super->data_block_size) != pmd->data_block_size) {
698 DMERR("changing the data block size (from %u to %llu) is not supported",
699 le32_to_cpu(disk_super->data_block_size),
700 (unsigned long long)pmd->data_block_size);
702 goto bad_unlock_sblock;
705 r = __check_incompat_features(disk_super, pmd);
707 goto bad_unlock_sblock;
709 r = dm_tm_open_with_sm(pmd->bm, THIN_SUPERBLOCK_LOCATION,
710 disk_super->metadata_space_map_root,
711 sizeof(disk_super->metadata_space_map_root),
712 &pmd->tm, &pmd->metadata_sm);
714 DMERR("tm_open_with_sm failed");
715 goto bad_unlock_sblock;
718 pmd->data_sm = dm_sm_disk_open(pmd->tm, disk_super->data_space_map_root,
719 sizeof(disk_super->data_space_map_root));
720 if (IS_ERR(pmd->data_sm)) {
721 DMERR("sm_disk_open failed");
722 r = PTR_ERR(pmd->data_sm);
726 pmd->nb_tm = dm_tm_create_non_blocking_clone(pmd->tm);
728 DMERR("could not create non-blocking clone tm");
730 goto bad_cleanup_data_sm;
734 * For pool metadata opening process, root setting is redundant
735 * because it will be set again in __begin_transaction(). But dm
736 * pool aborting process really needs to get last transaction's
737 * root to avoid accessing broken btree.
739 pmd->root = le64_to_cpu(disk_super->data_mapping_root);
740 pmd->details_root = le64_to_cpu(disk_super->device_details_root);
742 __setup_btree_details(pmd);
743 dm_bm_unlock(sblock);
748 dm_sm_destroy(pmd->data_sm);
750 dm_tm_destroy(pmd->tm);
751 dm_sm_destroy(pmd->metadata_sm);
753 dm_bm_unlock(sblock);
758 static int __open_or_format_metadata(struct dm_pool_metadata *pmd, bool format_device)
762 r = __superblock_all_zeroes(pmd->bm, &unformatted);
767 return format_device ? __format_metadata(pmd) : -EPERM;
769 return __open_metadata(pmd);
772 static int __create_persistent_data_objects(struct dm_pool_metadata *pmd, bool format_device)
776 pmd->bm = dm_block_manager_create(pmd->bdev, THIN_METADATA_BLOCK_SIZE << SECTOR_SHIFT,
777 THIN_MAX_CONCURRENT_LOCKS);
778 if (IS_ERR(pmd->bm)) {
779 DMERR("could not create block manager");
780 r = PTR_ERR(pmd->bm);
785 r = __open_or_format_metadata(pmd, format_device);
787 dm_block_manager_destroy(pmd->bm);
794 static void __destroy_persistent_data_objects(struct dm_pool_metadata *pmd,
797 dm_sm_destroy(pmd->data_sm);
798 dm_sm_destroy(pmd->metadata_sm);
799 dm_tm_destroy(pmd->nb_tm);
800 dm_tm_destroy(pmd->tm);
802 dm_block_manager_destroy(pmd->bm);
805 static int __begin_transaction(struct dm_pool_metadata *pmd)
808 struct thin_disk_superblock *disk_super;
809 struct dm_block *sblock;
812 * We re-read the superblock every time. Shouldn't need to do this
815 r = dm_bm_read_lock(pmd->bm, THIN_SUPERBLOCK_LOCATION,
816 &sb_validator, &sblock);
820 disk_super = dm_block_data(sblock);
821 pmd->time = le32_to_cpu(disk_super->time);
822 pmd->root = le64_to_cpu(disk_super->data_mapping_root);
823 pmd->details_root = le64_to_cpu(disk_super->device_details_root);
824 pmd->trans_id = le64_to_cpu(disk_super->trans_id);
825 pmd->flags = le32_to_cpu(disk_super->flags);
826 pmd->data_block_size = le32_to_cpu(disk_super->data_block_size);
828 dm_bm_unlock(sblock);
832 static int __write_changed_details(struct dm_pool_metadata *pmd)
835 struct dm_thin_device *td, *tmp;
836 struct disk_device_details details;
839 list_for_each_entry_safe(td, tmp, &pmd->thin_devices, list) {
845 details.mapped_blocks = cpu_to_le64(td->mapped_blocks);
846 details.transaction_id = cpu_to_le64(td->transaction_id);
847 details.creation_time = cpu_to_le32(td->creation_time);
848 details.snapshotted_time = cpu_to_le32(td->snapshotted_time);
849 __dm_bless_for_disk(&details);
851 r = dm_btree_insert(&pmd->details_info, pmd->details_root,
852 &key, &details, &pmd->details_root);
867 static int __commit_transaction(struct dm_pool_metadata *pmd)
870 struct thin_disk_superblock *disk_super;
871 struct dm_block *sblock;
874 * We need to know if the thin_disk_superblock exceeds a 512-byte sector.
876 BUILD_BUG_ON(sizeof(struct thin_disk_superblock) > 512);
877 BUG_ON(!rwsem_is_locked(&pmd->root_lock));
879 if (unlikely(!pmd->in_service))
882 if (pmd->pre_commit_fn) {
883 r = pmd->pre_commit_fn(pmd->pre_commit_context);
885 DMERR("pre-commit callback failed");
890 r = __write_changed_details(pmd);
894 r = dm_sm_commit(pmd->data_sm);
898 r = dm_tm_pre_commit(pmd->tm);
902 r = save_sm_roots(pmd);
906 r = superblock_lock(pmd, &sblock);
910 disk_super = dm_block_data(sblock);
911 disk_super->time = cpu_to_le32(pmd->time);
912 disk_super->data_mapping_root = cpu_to_le64(pmd->root);
913 disk_super->device_details_root = cpu_to_le64(pmd->details_root);
914 disk_super->trans_id = cpu_to_le64(pmd->trans_id);
915 disk_super->flags = cpu_to_le32(pmd->flags);
917 copy_sm_roots(pmd, disk_super);
919 return dm_tm_commit(pmd->tm, sblock);
922 static void __set_metadata_reserve(struct dm_pool_metadata *pmd)
926 dm_block_t max_blocks = 4096; /* 16M */
928 r = dm_sm_get_nr_blocks(pmd->metadata_sm, &total);
930 DMERR("could not get size of metadata device");
931 pmd->metadata_reserve = max_blocks;
933 pmd->metadata_reserve = min(max_blocks, div_u64(total, 10));
936 struct dm_pool_metadata *dm_pool_metadata_open(struct block_device *bdev,
937 sector_t data_block_size,
941 struct dm_pool_metadata *pmd;
943 pmd = kmalloc(sizeof(*pmd), GFP_KERNEL);
945 DMERR("could not allocate metadata struct");
946 return ERR_PTR(-ENOMEM);
949 init_rwsem(&pmd->root_lock);
951 INIT_LIST_HEAD(&pmd->thin_devices);
952 pmd->fail_io = false;
953 pmd->in_service = false;
955 pmd->data_block_size = data_block_size;
956 pmd->pre_commit_fn = NULL;
957 pmd->pre_commit_context = NULL;
959 r = __create_persistent_data_objects(pmd, format_device);
965 r = __begin_transaction(pmd);
967 if (dm_pool_metadata_close(pmd) < 0)
968 DMWARN("%s: dm_pool_metadata_close() failed.", __func__);
972 __set_metadata_reserve(pmd);
977 int dm_pool_metadata_close(struct dm_pool_metadata *pmd)
980 unsigned int open_devices = 0;
981 struct dm_thin_device *td, *tmp;
983 down_read(&pmd->root_lock);
984 list_for_each_entry_safe(td, tmp, &pmd->thin_devices, list) {
992 up_read(&pmd->root_lock);
995 DMERR("attempt to close pmd when %u device(s) are still open",
1000 pmd_write_lock_in_core(pmd);
1001 if (!pmd->fail_io && !dm_bm_is_read_only(pmd->bm)) {
1002 r = __commit_transaction(pmd);
1004 DMWARN("%s: __commit_transaction() failed, error = %d",
1007 pmd_write_unlock(pmd);
1009 __destroy_persistent_data_objects(pmd, true);
1016 * __open_device: Returns @td corresponding to device with id @dev,
1017 * creating it if @create is set and incrementing @td->open_count.
1018 * On failure, @td is undefined.
1020 static int __open_device(struct dm_pool_metadata *pmd,
1021 dm_thin_id dev, int create,
1022 struct dm_thin_device **td)
1025 struct dm_thin_device *td2;
1027 struct disk_device_details details_le;
1030 * If the device is already open, return it.
1032 list_for_each_entry(td2, &pmd->thin_devices, list)
1033 if (td2->id == dev) {
1035 * May not create an already-open device.
1046 * Check the device exists.
1048 r = dm_btree_lookup(&pmd->details_info, pmd->details_root,
1051 if (r != -ENODATA || !create)
1055 * Create new device.
1058 details_le.mapped_blocks = 0;
1059 details_le.transaction_id = cpu_to_le64(pmd->trans_id);
1060 details_le.creation_time = cpu_to_le32(pmd->time);
1061 details_le.snapshotted_time = cpu_to_le32(pmd->time);
1064 *td = kmalloc(sizeof(**td), GFP_NOIO);
1070 (*td)->open_count = 1;
1071 (*td)->changed = changed;
1072 (*td)->aborted_with_changes = false;
1073 (*td)->mapped_blocks = le64_to_cpu(details_le.mapped_blocks);
1074 (*td)->transaction_id = le64_to_cpu(details_le.transaction_id);
1075 (*td)->creation_time = le32_to_cpu(details_le.creation_time);
1076 (*td)->snapshotted_time = le32_to_cpu(details_le.snapshotted_time);
1078 list_add(&(*td)->list, &pmd->thin_devices);
1083 static void __close_device(struct dm_thin_device *td)
1088 static int __create_thin(struct dm_pool_metadata *pmd,
1092 dm_block_t dev_root;
1094 struct dm_thin_device *td;
1097 r = dm_btree_lookup(&pmd->details_info, pmd->details_root,
1103 * Create an empty btree for the mappings.
1105 r = dm_btree_empty(&pmd->bl_info, &dev_root);
1110 * Insert it into the main mapping tree.
1112 value = cpu_to_le64(dev_root);
1113 __dm_bless_for_disk(&value);
1114 r = dm_btree_insert(&pmd->tl_info, pmd->root, &key, &value, &pmd->root);
1116 dm_btree_del(&pmd->bl_info, dev_root);
1120 r = __open_device(pmd, dev, 1, &td);
1122 dm_btree_remove(&pmd->tl_info, pmd->root, &key, &pmd->root);
1123 dm_btree_del(&pmd->bl_info, dev_root);
1131 int dm_pool_create_thin(struct dm_pool_metadata *pmd, dm_thin_id dev)
1135 pmd_write_lock(pmd);
1137 r = __create_thin(pmd, dev);
1138 pmd_write_unlock(pmd);
1143 static int __set_snapshot_details(struct dm_pool_metadata *pmd,
1144 struct dm_thin_device *snap,
1145 dm_thin_id origin, uint32_t time)
1148 struct dm_thin_device *td;
1150 r = __open_device(pmd, origin, 0, &td);
1155 td->snapshotted_time = time;
1157 snap->mapped_blocks = td->mapped_blocks;
1158 snap->snapshotted_time = time;
1164 static int __create_snap(struct dm_pool_metadata *pmd,
1165 dm_thin_id dev, dm_thin_id origin)
1168 dm_block_t origin_root;
1169 uint64_t key = origin, dev_key = dev;
1170 struct dm_thin_device *td;
1173 /* check this device is unused */
1174 r = dm_btree_lookup(&pmd->details_info, pmd->details_root,
1179 /* find the mapping tree for the origin */
1180 r = dm_btree_lookup(&pmd->tl_info, pmd->root, &key, &value);
1183 origin_root = le64_to_cpu(value);
1185 /* clone the origin, an inc will do */
1186 dm_tm_inc(pmd->tm, origin_root);
1188 /* insert into the main mapping tree */
1189 value = cpu_to_le64(origin_root);
1190 __dm_bless_for_disk(&value);
1192 r = dm_btree_insert(&pmd->tl_info, pmd->root, &key, &value, &pmd->root);
1194 dm_tm_dec(pmd->tm, origin_root);
1200 r = __open_device(pmd, dev, 1, &td);
1204 r = __set_snapshot_details(pmd, td, origin, pmd->time);
1213 dm_btree_remove(&pmd->tl_info, pmd->root, &key, &pmd->root);
1214 dm_btree_remove(&pmd->details_info, pmd->details_root,
1215 &key, &pmd->details_root);
1219 int dm_pool_create_snap(struct dm_pool_metadata *pmd,
1225 pmd_write_lock(pmd);
1227 r = __create_snap(pmd, dev, origin);
1228 pmd_write_unlock(pmd);
1233 static int __delete_device(struct dm_pool_metadata *pmd, dm_thin_id dev)
1237 struct dm_thin_device *td;
1239 /* TODO: failure should mark the transaction invalid */
1240 r = __open_device(pmd, dev, 0, &td);
1244 if (td->open_count > 1) {
1249 list_del(&td->list);
1251 r = dm_btree_remove(&pmd->details_info, pmd->details_root,
1252 &key, &pmd->details_root);
1256 r = dm_btree_remove(&pmd->tl_info, pmd->root, &key, &pmd->root);
1263 int dm_pool_delete_thin_device(struct dm_pool_metadata *pmd,
1268 pmd_write_lock(pmd);
1270 r = __delete_device(pmd, dev);
1271 pmd_write_unlock(pmd);
1276 int dm_pool_set_metadata_transaction_id(struct dm_pool_metadata *pmd,
1277 uint64_t current_id,
1282 pmd_write_lock(pmd);
1287 if (pmd->trans_id != current_id) {
1288 DMERR("mismatched transaction id");
1292 pmd->trans_id = new_id;
1296 pmd_write_unlock(pmd);
1301 int dm_pool_get_metadata_transaction_id(struct dm_pool_metadata *pmd,
1306 down_read(&pmd->root_lock);
1307 if (!pmd->fail_io) {
1308 *result = pmd->trans_id;
1311 up_read(&pmd->root_lock);
1316 static int __reserve_metadata_snap(struct dm_pool_metadata *pmd)
1319 struct thin_disk_superblock *disk_super;
1320 struct dm_block *copy, *sblock;
1321 dm_block_t held_root;
1324 * We commit to ensure the btree roots which we increment in a
1325 * moment are up to date.
1327 r = __commit_transaction(pmd);
1329 DMWARN("%s: __commit_transaction() failed, error = %d",
1335 * Copy the superblock.
1337 dm_sm_inc_block(pmd->metadata_sm, THIN_SUPERBLOCK_LOCATION);
1338 r = dm_tm_shadow_block(pmd->tm, THIN_SUPERBLOCK_LOCATION,
1339 &sb_validator, ©, &inc);
1345 held_root = dm_block_location(copy);
1346 disk_super = dm_block_data(copy);
1348 if (le64_to_cpu(disk_super->held_root)) {
1349 DMWARN("Pool metadata snapshot already exists: release this before taking another.");
1351 dm_tm_dec(pmd->tm, held_root);
1352 dm_tm_unlock(pmd->tm, copy);
1357 * Wipe the spacemap since we're not publishing this.
1359 memset(&disk_super->data_space_map_root, 0,
1360 sizeof(disk_super->data_space_map_root));
1361 memset(&disk_super->metadata_space_map_root, 0,
1362 sizeof(disk_super->metadata_space_map_root));
1365 * Increment the data structures that need to be preserved.
1367 dm_tm_inc(pmd->tm, le64_to_cpu(disk_super->data_mapping_root));
1368 dm_tm_inc(pmd->tm, le64_to_cpu(disk_super->device_details_root));
1369 dm_tm_unlock(pmd->tm, copy);
1372 * Write the held root into the superblock.
1374 r = superblock_lock(pmd, &sblock);
1376 dm_tm_dec(pmd->tm, held_root);
1380 disk_super = dm_block_data(sblock);
1381 disk_super->held_root = cpu_to_le64(held_root);
1382 dm_bm_unlock(sblock);
1386 int dm_pool_reserve_metadata_snap(struct dm_pool_metadata *pmd)
1390 pmd_write_lock(pmd);
1392 r = __reserve_metadata_snap(pmd);
1393 pmd_write_unlock(pmd);
1398 static int __release_metadata_snap(struct dm_pool_metadata *pmd)
1401 struct thin_disk_superblock *disk_super;
1402 struct dm_block *sblock, *copy;
1403 dm_block_t held_root;
1405 r = superblock_lock(pmd, &sblock);
1409 disk_super = dm_block_data(sblock);
1410 held_root = le64_to_cpu(disk_super->held_root);
1411 disk_super->held_root = cpu_to_le64(0);
1413 dm_bm_unlock(sblock);
1416 DMWARN("No pool metadata snapshot found: nothing to release.");
1420 r = dm_tm_read_lock(pmd->tm, held_root, &sb_validator, ©);
1424 disk_super = dm_block_data(copy);
1425 dm_btree_del(&pmd->info, le64_to_cpu(disk_super->data_mapping_root));
1426 dm_btree_del(&pmd->details_info, le64_to_cpu(disk_super->device_details_root));
1427 dm_sm_dec_block(pmd->metadata_sm, held_root);
1429 dm_tm_unlock(pmd->tm, copy);
1434 int dm_pool_release_metadata_snap(struct dm_pool_metadata *pmd)
1438 pmd_write_lock(pmd);
1440 r = __release_metadata_snap(pmd);
1441 pmd_write_unlock(pmd);
1446 static int __get_metadata_snap(struct dm_pool_metadata *pmd,
1450 struct thin_disk_superblock *disk_super;
1451 struct dm_block *sblock;
1453 r = dm_bm_read_lock(pmd->bm, THIN_SUPERBLOCK_LOCATION,
1454 &sb_validator, &sblock);
1458 disk_super = dm_block_data(sblock);
1459 *result = le64_to_cpu(disk_super->held_root);
1461 dm_bm_unlock(sblock);
1466 int dm_pool_get_metadata_snap(struct dm_pool_metadata *pmd,
1471 down_read(&pmd->root_lock);
1473 r = __get_metadata_snap(pmd, result);
1474 up_read(&pmd->root_lock);
1479 int dm_pool_open_thin_device(struct dm_pool_metadata *pmd, dm_thin_id dev,
1480 struct dm_thin_device **td)
1484 pmd_write_lock_in_core(pmd);
1486 r = __open_device(pmd, dev, 0, td);
1487 pmd_write_unlock(pmd);
1492 int dm_pool_close_thin_device(struct dm_thin_device *td)
1494 pmd_write_lock_in_core(td->pmd);
1496 pmd_write_unlock(td->pmd);
1501 dm_thin_id dm_thin_dev_id(struct dm_thin_device *td)
1507 * Check whether @time (of block creation) is older than @td's last snapshot.
1508 * If so then the associated block is shared with the last snapshot device.
1509 * Any block on a device created *after* the device last got snapshotted is
1510 * necessarily not shared.
1512 static bool __snapshotted_since(struct dm_thin_device *td, uint32_t time)
1514 return td->snapshotted_time > time;
1517 static void unpack_lookup_result(struct dm_thin_device *td, __le64 value,
1518 struct dm_thin_lookup_result *result)
1520 uint64_t block_time = 0;
1521 dm_block_t exception_block;
1522 uint32_t exception_time;
1524 block_time = le64_to_cpu(value);
1525 unpack_block_time(block_time, &exception_block, &exception_time);
1526 result->block = exception_block;
1527 result->shared = __snapshotted_since(td, exception_time);
1530 static int __find_block(struct dm_thin_device *td, dm_block_t block,
1531 int can_issue_io, struct dm_thin_lookup_result *result)
1535 struct dm_pool_metadata *pmd = td->pmd;
1536 dm_block_t keys[2] = { td->id, block };
1537 struct dm_btree_info *info;
1542 info = &pmd->nb_info;
1544 r = dm_btree_lookup(info, pmd->root, keys, &value);
1546 unpack_lookup_result(td, value, result);
1551 int dm_thin_find_block(struct dm_thin_device *td, dm_block_t block,
1552 int can_issue_io, struct dm_thin_lookup_result *result)
1555 struct dm_pool_metadata *pmd = td->pmd;
1557 down_read(&pmd->root_lock);
1559 up_read(&pmd->root_lock);
1563 r = __find_block(td, block, can_issue_io, result);
1565 up_read(&pmd->root_lock);
1569 static int __find_next_mapped_block(struct dm_thin_device *td, dm_block_t block,
1571 struct dm_thin_lookup_result *result)
1575 struct dm_pool_metadata *pmd = td->pmd;
1576 dm_block_t keys[2] = { td->id, block };
1578 r = dm_btree_lookup_next(&pmd->info, pmd->root, keys, vblock, &value);
1580 unpack_lookup_result(td, value, result);
1585 static int __find_mapped_range(struct dm_thin_device *td,
1586 dm_block_t begin, dm_block_t end,
1587 dm_block_t *thin_begin, dm_block_t *thin_end,
1588 dm_block_t *pool_begin, bool *maybe_shared)
1591 dm_block_t pool_end;
1592 struct dm_thin_lookup_result lookup;
1597 r = __find_next_mapped_block(td, begin, &begin, &lookup);
1604 *thin_begin = begin;
1605 *pool_begin = lookup.block;
1606 *maybe_shared = lookup.shared;
1609 pool_end = *pool_begin + 1;
1610 while (begin != end) {
1611 r = __find_block(td, begin, true, &lookup);
1619 if ((lookup.block != pool_end) ||
1620 (lookup.shared != *maybe_shared))
1631 int dm_thin_find_mapped_range(struct dm_thin_device *td,
1632 dm_block_t begin, dm_block_t end,
1633 dm_block_t *thin_begin, dm_block_t *thin_end,
1634 dm_block_t *pool_begin, bool *maybe_shared)
1637 struct dm_pool_metadata *pmd = td->pmd;
1639 down_read(&pmd->root_lock);
1640 if (!pmd->fail_io) {
1641 r = __find_mapped_range(td, begin, end, thin_begin, thin_end,
1642 pool_begin, maybe_shared);
1644 up_read(&pmd->root_lock);
1649 static int __insert(struct dm_thin_device *td, dm_block_t block,
1650 dm_block_t data_block)
1654 struct dm_pool_metadata *pmd = td->pmd;
1655 dm_block_t keys[2] = { td->id, block };
1657 value = cpu_to_le64(pack_block_time(data_block, pmd->time));
1658 __dm_bless_for_disk(&value);
1660 r = dm_btree_insert_notify(&pmd->info, pmd->root, keys, &value,
1661 &pmd->root, &inserted);
1667 td->mapped_blocks++;
1672 int dm_thin_insert_block(struct dm_thin_device *td, dm_block_t block,
1673 dm_block_t data_block)
1677 pmd_write_lock(td->pmd);
1678 if (!td->pmd->fail_io)
1679 r = __insert(td, block, data_block);
1680 pmd_write_unlock(td->pmd);
1685 static int __remove_range(struct dm_thin_device *td, dm_block_t begin, dm_block_t end)
1688 unsigned int count, total_count = 0;
1689 struct dm_pool_metadata *pmd = td->pmd;
1690 dm_block_t keys[1] = { td->id };
1692 dm_block_t mapping_root;
1695 * Find the mapping tree
1697 r = dm_btree_lookup(&pmd->tl_info, pmd->root, keys, &value);
1702 * Remove from the mapping tree, taking care to inc the
1703 * ref count so it doesn't get deleted.
1705 mapping_root = le64_to_cpu(value);
1706 dm_tm_inc(pmd->tm, mapping_root);
1707 r = dm_btree_remove(&pmd->tl_info, pmd->root, keys, &pmd->root);
1712 * Remove leaves stops at the first unmapped entry, so we have to
1713 * loop round finding mapped ranges.
1715 while (begin < end) {
1716 r = dm_btree_lookup_next(&pmd->bl_info, mapping_root, &begin, &begin, &value);
1726 r = dm_btree_remove_leaves(&pmd->bl_info, mapping_root, &begin, end, &mapping_root, &count);
1730 total_count += count;
1733 td->mapped_blocks -= total_count;
1737 * Reinsert the mapping tree.
1739 value = cpu_to_le64(mapping_root);
1740 __dm_bless_for_disk(&value);
1741 return dm_btree_insert(&pmd->tl_info, pmd->root, keys, &value, &pmd->root);
1744 int dm_thin_remove_range(struct dm_thin_device *td,
1745 dm_block_t begin, dm_block_t end)
1749 pmd_write_lock(td->pmd);
1750 if (!td->pmd->fail_io)
1751 r = __remove_range(td, begin, end);
1752 pmd_write_unlock(td->pmd);
1757 int dm_pool_block_is_shared(struct dm_pool_metadata *pmd, dm_block_t b, bool *result)
1762 down_read(&pmd->root_lock);
1763 r = dm_sm_get_count(pmd->data_sm, b, &ref_count);
1765 *result = (ref_count > 1);
1766 up_read(&pmd->root_lock);
1771 int dm_pool_inc_data_range(struct dm_pool_metadata *pmd, dm_block_t b, dm_block_t e)
1775 pmd_write_lock(pmd);
1776 r = dm_sm_inc_blocks(pmd->data_sm, b, e);
1777 pmd_write_unlock(pmd);
1782 int dm_pool_dec_data_range(struct dm_pool_metadata *pmd, dm_block_t b, dm_block_t e)
1786 pmd_write_lock(pmd);
1787 r = dm_sm_dec_blocks(pmd->data_sm, b, e);
1788 pmd_write_unlock(pmd);
1793 bool dm_thin_changed_this_transaction(struct dm_thin_device *td)
1797 down_read(&td->pmd->root_lock);
1799 up_read(&td->pmd->root_lock);
1804 bool dm_pool_changed_this_transaction(struct dm_pool_metadata *pmd)
1807 struct dm_thin_device *td, *tmp;
1809 down_read(&pmd->root_lock);
1810 list_for_each_entry_safe(td, tmp, &pmd->thin_devices, list) {
1816 up_read(&pmd->root_lock);
1821 bool dm_thin_aborted_changes(struct dm_thin_device *td)
1825 down_read(&td->pmd->root_lock);
1826 r = td->aborted_with_changes;
1827 up_read(&td->pmd->root_lock);
1832 int dm_pool_alloc_data_block(struct dm_pool_metadata *pmd, dm_block_t *result)
1836 pmd_write_lock(pmd);
1838 r = dm_sm_new_block(pmd->data_sm, result);
1839 pmd_write_unlock(pmd);
1844 int dm_pool_commit_metadata(struct dm_pool_metadata *pmd)
1849 * Care is taken to not have commit be what
1850 * triggers putting the thin-pool in-service.
1852 pmd_write_lock_in_core(pmd);
1856 r = __commit_transaction(pmd);
1861 * Open the next transaction.
1863 r = __begin_transaction(pmd);
1865 pmd_write_unlock(pmd);
1869 static void __set_abort_with_changes_flags(struct dm_pool_metadata *pmd)
1871 struct dm_thin_device *td;
1873 list_for_each_entry(td, &pmd->thin_devices, list)
1874 td->aborted_with_changes = td->changed;
1877 int dm_pool_abort_metadata(struct dm_pool_metadata *pmd)
1880 struct dm_block_manager *old_bm = NULL, *new_bm = NULL;
1882 /* fail_io is double-checked with pmd->root_lock held below */
1883 if (unlikely(pmd->fail_io))
1887 * Replacement block manager (new_bm) is created and old_bm destroyed outside of
1888 * pmd root_lock to avoid ABBA deadlock that would result (due to life-cycle of
1889 * shrinker associated with the block manager's bufio client vs pmd root_lock).
1890 * - must take shrinker_mutex without holding pmd->root_lock
1892 new_bm = dm_block_manager_create(pmd->bdev, THIN_METADATA_BLOCK_SIZE << SECTOR_SHIFT,
1893 THIN_MAX_CONCURRENT_LOCKS);
1895 pmd_write_lock(pmd);
1897 pmd_write_unlock(pmd);
1901 __set_abort_with_changes_flags(pmd);
1902 __destroy_persistent_data_objects(pmd, false);
1904 if (IS_ERR(new_bm)) {
1905 DMERR("could not create block manager during abort");
1907 r = PTR_ERR(new_bm);
1912 r = __open_or_format_metadata(pmd, false);
1920 pmd->fail_io = true;
1921 pmd_write_unlock(pmd);
1922 dm_block_manager_destroy(old_bm);
1924 if (new_bm && !IS_ERR(new_bm))
1925 dm_block_manager_destroy(new_bm);
1930 int dm_pool_get_free_block_count(struct dm_pool_metadata *pmd, dm_block_t *result)
1934 down_read(&pmd->root_lock);
1936 r = dm_sm_get_nr_free(pmd->data_sm, result);
1937 up_read(&pmd->root_lock);
1942 int dm_pool_get_free_metadata_block_count(struct dm_pool_metadata *pmd,
1947 down_read(&pmd->root_lock);
1949 r = dm_sm_get_nr_free(pmd->metadata_sm, result);
1952 if (*result < pmd->metadata_reserve)
1955 *result -= pmd->metadata_reserve;
1957 up_read(&pmd->root_lock);
1962 int dm_pool_get_metadata_dev_size(struct dm_pool_metadata *pmd,
1967 down_read(&pmd->root_lock);
1969 r = dm_sm_get_nr_blocks(pmd->metadata_sm, result);
1970 up_read(&pmd->root_lock);
1975 int dm_pool_get_data_dev_size(struct dm_pool_metadata *pmd, dm_block_t *result)
1979 down_read(&pmd->root_lock);
1981 r = dm_sm_get_nr_blocks(pmd->data_sm, result);
1982 up_read(&pmd->root_lock);
1987 int dm_thin_get_mapped_count(struct dm_thin_device *td, dm_block_t *result)
1990 struct dm_pool_metadata *pmd = td->pmd;
1992 down_read(&pmd->root_lock);
1993 if (!pmd->fail_io) {
1994 *result = td->mapped_blocks;
1997 up_read(&pmd->root_lock);
2002 static int __highest_block(struct dm_thin_device *td, dm_block_t *result)
2006 dm_block_t thin_root;
2007 struct dm_pool_metadata *pmd = td->pmd;
2009 r = dm_btree_lookup(&pmd->tl_info, pmd->root, &td->id, &value_le);
2013 thin_root = le64_to_cpu(value_le);
2015 return dm_btree_find_highest_key(&pmd->bl_info, thin_root, result);
2018 int dm_thin_get_highest_mapped_block(struct dm_thin_device *td,
2022 struct dm_pool_metadata *pmd = td->pmd;
2024 down_read(&pmd->root_lock);
2026 r = __highest_block(td, result);
2027 up_read(&pmd->root_lock);
2032 static int __resize_space_map(struct dm_space_map *sm, dm_block_t new_count)
2035 dm_block_t old_count;
2037 r = dm_sm_get_nr_blocks(sm, &old_count);
2041 if (new_count == old_count)
2044 if (new_count < old_count) {
2045 DMERR("cannot reduce size of space map");
2049 return dm_sm_extend(sm, new_count - old_count);
2052 int dm_pool_resize_data_dev(struct dm_pool_metadata *pmd, dm_block_t new_count)
2056 pmd_write_lock(pmd);
2058 r = __resize_space_map(pmd->data_sm, new_count);
2059 pmd_write_unlock(pmd);
2064 int dm_pool_resize_metadata_dev(struct dm_pool_metadata *pmd, dm_block_t new_count)
2068 pmd_write_lock(pmd);
2069 if (!pmd->fail_io) {
2070 r = __resize_space_map(pmd->metadata_sm, new_count);
2072 __set_metadata_reserve(pmd);
2074 pmd_write_unlock(pmd);
2079 void dm_pool_metadata_read_only(struct dm_pool_metadata *pmd)
2081 pmd_write_lock_in_core(pmd);
2082 dm_bm_set_read_only(pmd->bm);
2083 pmd_write_unlock(pmd);
2086 void dm_pool_metadata_read_write(struct dm_pool_metadata *pmd)
2088 pmd_write_lock_in_core(pmd);
2089 dm_bm_set_read_write(pmd->bm);
2090 pmd_write_unlock(pmd);
2093 int dm_pool_register_metadata_threshold(struct dm_pool_metadata *pmd,
2094 dm_block_t threshold,
2095 dm_sm_threshold_fn fn,
2100 pmd_write_lock_in_core(pmd);
2101 if (!pmd->fail_io) {
2102 r = dm_sm_register_threshold_callback(pmd->metadata_sm,
2103 threshold, fn, context);
2105 pmd_write_unlock(pmd);
2110 void dm_pool_register_pre_commit_callback(struct dm_pool_metadata *pmd,
2111 dm_pool_pre_commit_fn fn,
2114 pmd_write_lock_in_core(pmd);
2115 pmd->pre_commit_fn = fn;
2116 pmd->pre_commit_context = context;
2117 pmd_write_unlock(pmd);
2120 int dm_pool_metadata_set_needs_check(struct dm_pool_metadata *pmd)
2123 struct dm_block *sblock;
2124 struct thin_disk_superblock *disk_super;
2126 pmd_write_lock(pmd);
2130 pmd->flags |= THIN_METADATA_NEEDS_CHECK_FLAG;
2132 r = superblock_lock(pmd, &sblock);
2134 DMERR("couldn't lock superblock");
2138 disk_super = dm_block_data(sblock);
2139 disk_super->flags = cpu_to_le32(pmd->flags);
2141 dm_bm_unlock(sblock);
2143 pmd_write_unlock(pmd);
2147 bool dm_pool_metadata_needs_check(struct dm_pool_metadata *pmd)
2151 down_read(&pmd->root_lock);
2152 needs_check = pmd->flags & THIN_METADATA_NEEDS_CHECK_FLAG;
2153 up_read(&pmd->root_lock);
2158 void dm_pool_issue_prefetches(struct dm_pool_metadata *pmd)
2160 down_read(&pmd->root_lock);
2162 dm_tm_issue_prefetches(pmd->tm);
2163 up_read(&pmd->root_lock);