2 * Copyright (C) 2011-2012 Red Hat, Inc.
4 * This file is released under the GPL.
7 #include "dm-thin-metadata.h"
8 #include "persistent-data/dm-btree.h"
9 #include "persistent-data/dm-space-map.h"
10 #include "persistent-data/dm-space-map-disk.h"
11 #include "persistent-data/dm-transaction-manager.h"
13 #include <linux/list.h>
14 #include <linux/device-mapper.h>
15 #include <linux/workqueue.h>
17 /*--------------------------------------------------------------------------
18 * As far as the metadata goes, there is:
20 * - A superblock in block zero, taking up fewer than 512 bytes for
23 * - A space map managing the metadata blocks.
25 * - A space map managing the data blocks.
27 * - A btree mapping our internal thin dev ids onto struct disk_device_details.
29 * - A hierarchical btree, with 2 levels which effectively maps (thin
30 * dev id, virtual block) -> block_time. Block time is a 64-bit
31 * field holding the time in the low 24 bits, and block in the top 40
34 * BTrees consist solely of btree_nodes, that fill a block. Some are
35 * internal nodes, as such their values are a __le64 pointing to other
36 * nodes. Leaf nodes can store data of any reasonable size (ie. much
37 * smaller than the block size). The nodes consist of the header,
38 * followed by an array of keys, followed by an array of values. We have
39 * to binary search on the keys so they're all held together to help the
42 * Space maps have 2 btrees:
44 * - One maps a uint64_t onto a struct index_entry. Which points to a
45 * bitmap block, and has some details about how many free entries there
48 * - The bitmap blocks have a header (for the checksum). Then the rest
49 * of the block is pairs of bits. With the meaning being:
54 * 3 - ref count is higher than 2
56 * - If the count is higher than 2 then the ref count is entered in a
57 * second btree that directly maps the block_address to a uint32_t ref
60 * The space map metadata variant doesn't have a bitmaps btree. Instead
61 * it has one single blocks worth of index_entries. This avoids
62 * recursive issues with the bitmap btree needing to allocate space in
63 * order to insert. With a small data block size such as 64k the
64 * metadata support data devices that are hundreds of terrabytes.
66 * The space maps allocate space linearly from front to back. Space that
67 * is freed in a transaction is never recycled within that transaction.
68 * To try and avoid fragmenting _free_ space the allocator always goes
69 * back and fills in gaps.
71 * All metadata io is in THIN_METADATA_BLOCK_SIZE sized/aligned chunks
72 * from the block manager.
73 *--------------------------------------------------------------------------*/
75 #define DM_MSG_PREFIX "thin metadata"
77 #define THIN_SUPERBLOCK_MAGIC 27022010
78 #define THIN_SUPERBLOCK_LOCATION 0
79 #define THIN_VERSION 2
80 #define SECTOR_TO_BLOCK_SHIFT 3
84 * 3 for btree insert +
85 * 2 for btree lookup used within space map
87 * 2 for shadow spine +
88 * 4 for rebalance 3 child node
90 #define THIN_MAX_CONCURRENT_LOCKS 6
92 /* This should be plenty */
93 #define SPACE_MAP_ROOT_SIZE 128
96 * Little endian on-disk superblock and device details.
98 struct thin_disk_superblock {
99 __le32 csum; /* Checksum of superblock except for this field. */
101 __le64 blocknr; /* This block number, dm_block_t. */
111 * Root held by userspace transactions.
115 __u8 data_space_map_root[SPACE_MAP_ROOT_SIZE];
116 __u8 metadata_space_map_root[SPACE_MAP_ROOT_SIZE];
119 * 2-level btree mapping (dev_id, (dev block, time)) -> data block
121 __le64 data_mapping_root;
124 * Device detail root mapping dev_id -> device_details
126 __le64 device_details_root;
128 __le32 data_block_size; /* In 512-byte sectors. */
130 __le32 metadata_block_size; /* In 512-byte sectors. */
131 __le64 metadata_nr_blocks;
134 __le32 compat_ro_flags;
135 __le32 incompat_flags;
138 struct disk_device_details {
139 __le64 mapped_blocks;
140 __le64 transaction_id; /* When created. */
141 __le32 creation_time;
142 __le32 snapshotted_time;
145 struct dm_pool_metadata {
146 struct hlist_node hash;
148 struct block_device *bdev;
149 struct dm_block_manager *bm;
150 struct dm_space_map *metadata_sm;
151 struct dm_space_map *data_sm;
152 struct dm_transaction_manager *tm;
153 struct dm_transaction_manager *nb_tm;
157 * First level holds thin_dev_t.
158 * Second level holds mappings.
160 struct dm_btree_info info;
163 * Non-blocking version of the above.
165 struct dm_btree_info nb_info;
168 * Just the top level for deleting whole devices.
170 struct dm_btree_info tl_info;
173 * Just the bottom level for creating new devices.
175 struct dm_btree_info bl_info;
178 * Describes the device details btree.
180 struct dm_btree_info details_info;
182 struct rw_semaphore root_lock;
185 dm_block_t details_root;
186 struct list_head thin_devices;
189 sector_t data_block_size;
192 * Pre-commit callback.
194 * This allows the thin provisioning target to run a callback before
195 * the metadata are committed.
197 dm_pool_pre_commit_fn pre_commit_fn;
198 void *pre_commit_context;
201 * We reserve a section of the metadata for commit overhead.
202 * All reported space does *not* include this.
204 dm_block_t metadata_reserve;
207 * Set if a transaction has to be aborted but the attempt to roll back
208 * to the previous (good) transaction failed. The only pool metadata
209 * operation possible in this state is the closing of the device.
214 * Set once a thin-pool has been accessed through one of the interfaces
215 * that imply the pool is in-service (e.g. thin devices created/deleted,
216 * thin-pool message, metadata snapshots, etc).
221 * Reading the space map roots can fail, so we read it into these
222 * buffers before the superblock is locked and updated.
224 __u8 data_space_map_root[SPACE_MAP_ROOT_SIZE];
225 __u8 metadata_space_map_root[SPACE_MAP_ROOT_SIZE];
228 struct dm_thin_device {
229 struct list_head list;
230 struct dm_pool_metadata *pmd;
235 bool aborted_with_changes:1;
236 uint64_t mapped_blocks;
237 uint64_t transaction_id;
238 uint32_t creation_time;
239 uint32_t snapshotted_time;
242 /*----------------------------------------------------------------
243 * superblock validator
244 *--------------------------------------------------------------*/
246 #define SUPERBLOCK_CSUM_XOR 160774
248 static void sb_prepare_for_write(struct dm_block_validator *v,
252 struct thin_disk_superblock *disk_super = dm_block_data(b);
254 disk_super->blocknr = cpu_to_le64(dm_block_location(b));
255 disk_super->csum = cpu_to_le32(dm_bm_checksum(&disk_super->flags,
256 block_size - sizeof(__le32),
257 SUPERBLOCK_CSUM_XOR));
260 static int sb_check(struct dm_block_validator *v,
264 struct thin_disk_superblock *disk_super = dm_block_data(b);
267 if (dm_block_location(b) != le64_to_cpu(disk_super->blocknr)) {
268 DMERR("sb_check failed: blocknr %llu: "
269 "wanted %llu", le64_to_cpu(disk_super->blocknr),
270 (unsigned long long)dm_block_location(b));
274 if (le64_to_cpu(disk_super->magic) != THIN_SUPERBLOCK_MAGIC) {
275 DMERR("sb_check failed: magic %llu: "
276 "wanted %llu", le64_to_cpu(disk_super->magic),
277 (unsigned long long)THIN_SUPERBLOCK_MAGIC);
281 csum_le = cpu_to_le32(dm_bm_checksum(&disk_super->flags,
282 block_size - sizeof(__le32),
283 SUPERBLOCK_CSUM_XOR));
284 if (csum_le != disk_super->csum) {
285 DMERR("sb_check failed: csum %u: wanted %u",
286 le32_to_cpu(csum_le), le32_to_cpu(disk_super->csum));
293 static struct dm_block_validator sb_validator = {
294 .name = "superblock",
295 .prepare_for_write = sb_prepare_for_write,
299 /*----------------------------------------------------------------
300 * Methods for the btree value types
301 *--------------------------------------------------------------*/
303 static uint64_t pack_block_time(dm_block_t b, uint32_t t)
305 return (b << 24) | t;
308 static void unpack_block_time(uint64_t v, dm_block_t *b, uint32_t *t)
311 *t = v & ((1 << 24) - 1);
314 static void data_block_inc(void *context, const void *value_le)
316 struct dm_space_map *sm = context;
321 memcpy(&v_le, value_le, sizeof(v_le));
322 unpack_block_time(le64_to_cpu(v_le), &b, &t);
323 dm_sm_inc_block(sm, b);
326 static void data_block_dec(void *context, const void *value_le)
328 struct dm_space_map *sm = context;
333 memcpy(&v_le, value_le, sizeof(v_le));
334 unpack_block_time(le64_to_cpu(v_le), &b, &t);
335 dm_sm_dec_block(sm, b);
338 static int data_block_equal(void *context, const void *value1_le, const void *value2_le)
344 memcpy(&v1_le, value1_le, sizeof(v1_le));
345 memcpy(&v2_le, value2_le, sizeof(v2_le));
346 unpack_block_time(le64_to_cpu(v1_le), &b1, &t);
347 unpack_block_time(le64_to_cpu(v2_le), &b2, &t);
352 static void subtree_inc(void *context, const void *value)
354 struct dm_btree_info *info = context;
358 memcpy(&root_le, value, sizeof(root_le));
359 root = le64_to_cpu(root_le);
360 dm_tm_inc(info->tm, root);
363 static void subtree_dec(void *context, const void *value)
365 struct dm_btree_info *info = context;
369 memcpy(&root_le, value, sizeof(root_le));
370 root = le64_to_cpu(root_le);
371 if (dm_btree_del(info, root))
372 DMERR("btree delete failed");
375 static int subtree_equal(void *context, const void *value1_le, const void *value2_le)
378 memcpy(&v1_le, value1_le, sizeof(v1_le));
379 memcpy(&v2_le, value2_le, sizeof(v2_le));
381 return v1_le == v2_le;
384 /*----------------------------------------------------------------*/
387 * Variant that is used for in-core only changes or code that
388 * shouldn't put the pool in service on its own (e.g. commit).
390 static inline void pmd_write_lock_in_core(struct dm_pool_metadata *pmd)
391 __acquires(pmd->root_lock)
393 down_write(&pmd->root_lock);
396 static inline void pmd_write_lock(struct dm_pool_metadata *pmd)
398 pmd_write_lock_in_core(pmd);
399 if (unlikely(!pmd->in_service))
400 pmd->in_service = true;
403 static inline void pmd_write_unlock(struct dm_pool_metadata *pmd)
404 __releases(pmd->root_lock)
406 up_write(&pmd->root_lock);
409 /*----------------------------------------------------------------*/
411 static int superblock_lock_zero(struct dm_pool_metadata *pmd,
412 struct dm_block **sblock)
414 return dm_bm_write_lock_zero(pmd->bm, THIN_SUPERBLOCK_LOCATION,
415 &sb_validator, sblock);
418 static int superblock_lock(struct dm_pool_metadata *pmd,
419 struct dm_block **sblock)
421 return dm_bm_write_lock(pmd->bm, THIN_SUPERBLOCK_LOCATION,
422 &sb_validator, sblock);
425 static int __superblock_all_zeroes(struct dm_block_manager *bm, int *result)
430 __le64 *data_le, zero = cpu_to_le64(0);
431 unsigned block_size = dm_bm_block_size(bm) / sizeof(__le64);
434 * We can't use a validator here - it may be all zeroes.
436 r = dm_bm_read_lock(bm, THIN_SUPERBLOCK_LOCATION, NULL, &b);
440 data_le = dm_block_data(b);
442 for (i = 0; i < block_size; i++) {
443 if (data_le[i] != zero) {
454 static void __setup_btree_details(struct dm_pool_metadata *pmd)
456 pmd->info.tm = pmd->tm;
457 pmd->info.levels = 2;
458 pmd->info.value_type.context = pmd->data_sm;
459 pmd->info.value_type.size = sizeof(__le64);
460 pmd->info.value_type.inc = data_block_inc;
461 pmd->info.value_type.dec = data_block_dec;
462 pmd->info.value_type.equal = data_block_equal;
464 memcpy(&pmd->nb_info, &pmd->info, sizeof(pmd->nb_info));
465 pmd->nb_info.tm = pmd->nb_tm;
467 pmd->tl_info.tm = pmd->tm;
468 pmd->tl_info.levels = 1;
469 pmd->tl_info.value_type.context = &pmd->bl_info;
470 pmd->tl_info.value_type.size = sizeof(__le64);
471 pmd->tl_info.value_type.inc = subtree_inc;
472 pmd->tl_info.value_type.dec = subtree_dec;
473 pmd->tl_info.value_type.equal = subtree_equal;
475 pmd->bl_info.tm = pmd->tm;
476 pmd->bl_info.levels = 1;
477 pmd->bl_info.value_type.context = pmd->data_sm;
478 pmd->bl_info.value_type.size = sizeof(__le64);
479 pmd->bl_info.value_type.inc = data_block_inc;
480 pmd->bl_info.value_type.dec = data_block_dec;
481 pmd->bl_info.value_type.equal = data_block_equal;
483 pmd->details_info.tm = pmd->tm;
484 pmd->details_info.levels = 1;
485 pmd->details_info.value_type.context = NULL;
486 pmd->details_info.value_type.size = sizeof(struct disk_device_details);
487 pmd->details_info.value_type.inc = NULL;
488 pmd->details_info.value_type.dec = NULL;
489 pmd->details_info.value_type.equal = NULL;
492 static int save_sm_roots(struct dm_pool_metadata *pmd)
497 r = dm_sm_root_size(pmd->metadata_sm, &len);
501 r = dm_sm_copy_root(pmd->metadata_sm, &pmd->metadata_space_map_root, len);
505 r = dm_sm_root_size(pmd->data_sm, &len);
509 return dm_sm_copy_root(pmd->data_sm, &pmd->data_space_map_root, len);
512 static void copy_sm_roots(struct dm_pool_metadata *pmd,
513 struct thin_disk_superblock *disk)
515 memcpy(&disk->metadata_space_map_root,
516 &pmd->metadata_space_map_root,
517 sizeof(pmd->metadata_space_map_root));
519 memcpy(&disk->data_space_map_root,
520 &pmd->data_space_map_root,
521 sizeof(pmd->data_space_map_root));
524 static int __write_initial_superblock(struct dm_pool_metadata *pmd)
527 struct dm_block *sblock;
528 struct thin_disk_superblock *disk_super;
529 sector_t bdev_size = i_size_read(pmd->bdev->bd_inode) >> SECTOR_SHIFT;
531 if (bdev_size > THIN_METADATA_MAX_SECTORS)
532 bdev_size = THIN_METADATA_MAX_SECTORS;
534 r = dm_sm_commit(pmd->data_sm);
538 r = dm_tm_pre_commit(pmd->tm);
542 r = save_sm_roots(pmd);
546 r = superblock_lock_zero(pmd, &sblock);
550 disk_super = dm_block_data(sblock);
551 disk_super->flags = 0;
552 memset(disk_super->uuid, 0, sizeof(disk_super->uuid));
553 disk_super->magic = cpu_to_le64(THIN_SUPERBLOCK_MAGIC);
554 disk_super->version = cpu_to_le32(THIN_VERSION);
555 disk_super->time = 0;
556 disk_super->trans_id = 0;
557 disk_super->held_root = 0;
559 copy_sm_roots(pmd, disk_super);
561 disk_super->data_mapping_root = cpu_to_le64(pmd->root);
562 disk_super->device_details_root = cpu_to_le64(pmd->details_root);
563 disk_super->metadata_block_size = cpu_to_le32(THIN_METADATA_BLOCK_SIZE);
564 disk_super->metadata_nr_blocks = cpu_to_le64(bdev_size >> SECTOR_TO_BLOCK_SHIFT);
565 disk_super->data_block_size = cpu_to_le32(pmd->data_block_size);
567 return dm_tm_commit(pmd->tm, sblock);
570 static int __format_metadata(struct dm_pool_metadata *pmd)
574 r = dm_tm_create_with_sm(pmd->bm, THIN_SUPERBLOCK_LOCATION,
575 &pmd->tm, &pmd->metadata_sm);
577 DMERR("tm_create_with_sm failed");
581 pmd->data_sm = dm_sm_disk_create(pmd->tm, 0);
582 if (IS_ERR(pmd->data_sm)) {
583 DMERR("sm_disk_create failed");
584 r = PTR_ERR(pmd->data_sm);
588 pmd->nb_tm = dm_tm_create_non_blocking_clone(pmd->tm);
590 DMERR("could not create non-blocking clone tm");
592 goto bad_cleanup_data_sm;
595 __setup_btree_details(pmd);
597 r = dm_btree_empty(&pmd->info, &pmd->root);
599 goto bad_cleanup_nb_tm;
601 r = dm_btree_empty(&pmd->details_info, &pmd->details_root);
603 DMERR("couldn't create devices root");
604 goto bad_cleanup_nb_tm;
607 r = __write_initial_superblock(pmd);
609 goto bad_cleanup_nb_tm;
614 dm_tm_destroy(pmd->nb_tm);
616 dm_sm_destroy(pmd->data_sm);
618 dm_tm_destroy(pmd->tm);
619 dm_sm_destroy(pmd->metadata_sm);
624 static int __check_incompat_features(struct thin_disk_superblock *disk_super,
625 struct dm_pool_metadata *pmd)
629 features = le32_to_cpu(disk_super->incompat_flags) & ~THIN_FEATURE_INCOMPAT_SUPP;
631 DMERR("could not access metadata due to unsupported optional features (%lx).",
632 (unsigned long)features);
637 * Check for read-only metadata to skip the following RDWR checks.
639 if (get_disk_ro(pmd->bdev->bd_disk))
642 features = le32_to_cpu(disk_super->compat_ro_flags) & ~THIN_FEATURE_COMPAT_RO_SUPP;
644 DMERR("could not access metadata RDWR due to unsupported optional features (%lx).",
645 (unsigned long)features);
652 static int __open_metadata(struct dm_pool_metadata *pmd)
655 struct dm_block *sblock;
656 struct thin_disk_superblock *disk_super;
658 r = dm_bm_read_lock(pmd->bm, THIN_SUPERBLOCK_LOCATION,
659 &sb_validator, &sblock);
661 DMERR("couldn't read superblock");
665 disk_super = dm_block_data(sblock);
667 /* Verify the data block size hasn't changed */
668 if (le32_to_cpu(disk_super->data_block_size) != pmd->data_block_size) {
669 DMERR("changing the data block size (from %u to %llu) is not supported",
670 le32_to_cpu(disk_super->data_block_size),
671 (unsigned long long)pmd->data_block_size);
673 goto bad_unlock_sblock;
676 r = __check_incompat_features(disk_super, pmd);
678 goto bad_unlock_sblock;
680 r = dm_tm_open_with_sm(pmd->bm, THIN_SUPERBLOCK_LOCATION,
681 disk_super->metadata_space_map_root,
682 sizeof(disk_super->metadata_space_map_root),
683 &pmd->tm, &pmd->metadata_sm);
685 DMERR("tm_open_with_sm failed");
686 goto bad_unlock_sblock;
689 pmd->data_sm = dm_sm_disk_open(pmd->tm, disk_super->data_space_map_root,
690 sizeof(disk_super->data_space_map_root));
691 if (IS_ERR(pmd->data_sm)) {
692 DMERR("sm_disk_open failed");
693 r = PTR_ERR(pmd->data_sm);
697 pmd->nb_tm = dm_tm_create_non_blocking_clone(pmd->tm);
699 DMERR("could not create non-blocking clone tm");
701 goto bad_cleanup_data_sm;
705 * For pool metadata opening process, root setting is redundant
706 * because it will be set again in __begin_transaction(). But dm
707 * pool aborting process really needs to get last transaction's
708 * root to avoid accessing broken btree.
710 pmd->root = le64_to_cpu(disk_super->data_mapping_root);
711 pmd->details_root = le64_to_cpu(disk_super->device_details_root);
713 __setup_btree_details(pmd);
714 dm_bm_unlock(sblock);
719 dm_sm_destroy(pmd->data_sm);
721 dm_tm_destroy(pmd->tm);
722 dm_sm_destroy(pmd->metadata_sm);
724 dm_bm_unlock(sblock);
729 static int __open_or_format_metadata(struct dm_pool_metadata *pmd, bool format_device)
733 r = __superblock_all_zeroes(pmd->bm, &unformatted);
738 return format_device ? __format_metadata(pmd) : -EPERM;
740 return __open_metadata(pmd);
743 static int __create_persistent_data_objects(struct dm_pool_metadata *pmd, bool format_device)
747 pmd->bm = dm_block_manager_create(pmd->bdev, THIN_METADATA_BLOCK_SIZE << SECTOR_SHIFT,
748 THIN_MAX_CONCURRENT_LOCKS);
749 if (IS_ERR(pmd->bm)) {
750 DMERR("could not create block manager");
751 r = PTR_ERR(pmd->bm);
756 r = __open_or_format_metadata(pmd, format_device);
758 dm_block_manager_destroy(pmd->bm);
765 static void __destroy_persistent_data_objects(struct dm_pool_metadata *pmd,
768 dm_sm_destroy(pmd->data_sm);
769 dm_sm_destroy(pmd->metadata_sm);
770 dm_tm_destroy(pmd->nb_tm);
771 dm_tm_destroy(pmd->tm);
773 dm_block_manager_destroy(pmd->bm);
776 static int __begin_transaction(struct dm_pool_metadata *pmd)
779 struct thin_disk_superblock *disk_super;
780 struct dm_block *sblock;
783 * We re-read the superblock every time. Shouldn't need to do this
786 r = dm_bm_read_lock(pmd->bm, THIN_SUPERBLOCK_LOCATION,
787 &sb_validator, &sblock);
791 disk_super = dm_block_data(sblock);
792 pmd->time = le32_to_cpu(disk_super->time);
793 pmd->root = le64_to_cpu(disk_super->data_mapping_root);
794 pmd->details_root = le64_to_cpu(disk_super->device_details_root);
795 pmd->trans_id = le64_to_cpu(disk_super->trans_id);
796 pmd->flags = le32_to_cpu(disk_super->flags);
797 pmd->data_block_size = le32_to_cpu(disk_super->data_block_size);
799 dm_bm_unlock(sblock);
803 static int __write_changed_details(struct dm_pool_metadata *pmd)
806 struct dm_thin_device *td, *tmp;
807 struct disk_device_details details;
810 list_for_each_entry_safe(td, tmp, &pmd->thin_devices, list) {
816 details.mapped_blocks = cpu_to_le64(td->mapped_blocks);
817 details.transaction_id = cpu_to_le64(td->transaction_id);
818 details.creation_time = cpu_to_le32(td->creation_time);
819 details.snapshotted_time = cpu_to_le32(td->snapshotted_time);
820 __dm_bless_for_disk(&details);
822 r = dm_btree_insert(&pmd->details_info, pmd->details_root,
823 &key, &details, &pmd->details_root);
838 static int __commit_transaction(struct dm_pool_metadata *pmd)
841 struct thin_disk_superblock *disk_super;
842 struct dm_block *sblock;
845 * We need to know if the thin_disk_superblock exceeds a 512-byte sector.
847 BUILD_BUG_ON(sizeof(struct thin_disk_superblock) > 512);
848 BUG_ON(!rwsem_is_locked(&pmd->root_lock));
850 if (unlikely(!pmd->in_service))
853 if (pmd->pre_commit_fn) {
854 r = pmd->pre_commit_fn(pmd->pre_commit_context);
856 DMERR("pre-commit callback failed");
861 r = __write_changed_details(pmd);
865 r = dm_sm_commit(pmd->data_sm);
869 r = dm_tm_pre_commit(pmd->tm);
873 r = save_sm_roots(pmd);
877 r = superblock_lock(pmd, &sblock);
881 disk_super = dm_block_data(sblock);
882 disk_super->time = cpu_to_le32(pmd->time);
883 disk_super->data_mapping_root = cpu_to_le64(pmd->root);
884 disk_super->device_details_root = cpu_to_le64(pmd->details_root);
885 disk_super->trans_id = cpu_to_le64(pmd->trans_id);
886 disk_super->flags = cpu_to_le32(pmd->flags);
888 copy_sm_roots(pmd, disk_super);
890 return dm_tm_commit(pmd->tm, sblock);
893 static void __set_metadata_reserve(struct dm_pool_metadata *pmd)
897 dm_block_t max_blocks = 4096; /* 16M */
899 r = dm_sm_get_nr_blocks(pmd->metadata_sm, &total);
901 DMERR("could not get size of metadata device");
902 pmd->metadata_reserve = max_blocks;
904 pmd->metadata_reserve = min(max_blocks, div_u64(total, 10));
907 struct dm_pool_metadata *dm_pool_metadata_open(struct block_device *bdev,
908 sector_t data_block_size,
912 struct dm_pool_metadata *pmd;
914 pmd = kmalloc(sizeof(*pmd), GFP_KERNEL);
916 DMERR("could not allocate metadata struct");
917 return ERR_PTR(-ENOMEM);
920 init_rwsem(&pmd->root_lock);
922 INIT_LIST_HEAD(&pmd->thin_devices);
923 pmd->fail_io = false;
924 pmd->in_service = false;
926 pmd->data_block_size = data_block_size;
927 pmd->pre_commit_fn = NULL;
928 pmd->pre_commit_context = NULL;
930 r = __create_persistent_data_objects(pmd, format_device);
936 r = __begin_transaction(pmd);
938 if (dm_pool_metadata_close(pmd) < 0)
939 DMWARN("%s: dm_pool_metadata_close() failed.", __func__);
943 __set_metadata_reserve(pmd);
948 int dm_pool_metadata_close(struct dm_pool_metadata *pmd)
951 unsigned open_devices = 0;
952 struct dm_thin_device *td, *tmp;
954 down_read(&pmd->root_lock);
955 list_for_each_entry_safe(td, tmp, &pmd->thin_devices, list) {
963 up_read(&pmd->root_lock);
966 DMERR("attempt to close pmd when %u device(s) are still open",
971 pmd_write_lock_in_core(pmd);
972 if (!pmd->fail_io && !dm_bm_is_read_only(pmd->bm)) {
973 r = __commit_transaction(pmd);
975 DMWARN("%s: __commit_transaction() failed, error = %d",
978 pmd_write_unlock(pmd);
980 __destroy_persistent_data_objects(pmd, true);
987 * __open_device: Returns @td corresponding to device with id @dev,
988 * creating it if @create is set and incrementing @td->open_count.
989 * On failure, @td is undefined.
991 static int __open_device(struct dm_pool_metadata *pmd,
992 dm_thin_id dev, int create,
993 struct dm_thin_device **td)
996 struct dm_thin_device *td2;
998 struct disk_device_details details_le;
1001 * If the device is already open, return it.
1003 list_for_each_entry(td2, &pmd->thin_devices, list)
1004 if (td2->id == dev) {
1006 * May not create an already-open device.
1017 * Check the device exists.
1019 r = dm_btree_lookup(&pmd->details_info, pmd->details_root,
1022 if (r != -ENODATA || !create)
1026 * Create new device.
1029 details_le.mapped_blocks = 0;
1030 details_le.transaction_id = cpu_to_le64(pmd->trans_id);
1031 details_le.creation_time = cpu_to_le32(pmd->time);
1032 details_le.snapshotted_time = cpu_to_le32(pmd->time);
1035 *td = kmalloc(sizeof(**td), GFP_NOIO);
1041 (*td)->open_count = 1;
1042 (*td)->changed = changed;
1043 (*td)->aborted_with_changes = false;
1044 (*td)->mapped_blocks = le64_to_cpu(details_le.mapped_blocks);
1045 (*td)->transaction_id = le64_to_cpu(details_le.transaction_id);
1046 (*td)->creation_time = le32_to_cpu(details_le.creation_time);
1047 (*td)->snapshotted_time = le32_to_cpu(details_le.snapshotted_time);
1049 list_add(&(*td)->list, &pmd->thin_devices);
1054 static void __close_device(struct dm_thin_device *td)
1059 static int __create_thin(struct dm_pool_metadata *pmd,
1063 dm_block_t dev_root;
1065 struct dm_thin_device *td;
1068 r = dm_btree_lookup(&pmd->details_info, pmd->details_root,
1074 * Create an empty btree for the mappings.
1076 r = dm_btree_empty(&pmd->bl_info, &dev_root);
1081 * Insert it into the main mapping tree.
1083 value = cpu_to_le64(dev_root);
1084 __dm_bless_for_disk(&value);
1085 r = dm_btree_insert(&pmd->tl_info, pmd->root, &key, &value, &pmd->root);
1087 dm_btree_del(&pmd->bl_info, dev_root);
1091 r = __open_device(pmd, dev, 1, &td);
1093 dm_btree_remove(&pmd->tl_info, pmd->root, &key, &pmd->root);
1094 dm_btree_del(&pmd->bl_info, dev_root);
1102 int dm_pool_create_thin(struct dm_pool_metadata *pmd, dm_thin_id dev)
1106 pmd_write_lock(pmd);
1108 r = __create_thin(pmd, dev);
1109 pmd_write_unlock(pmd);
1114 static int __set_snapshot_details(struct dm_pool_metadata *pmd,
1115 struct dm_thin_device *snap,
1116 dm_thin_id origin, uint32_t time)
1119 struct dm_thin_device *td;
1121 r = __open_device(pmd, origin, 0, &td);
1126 td->snapshotted_time = time;
1128 snap->mapped_blocks = td->mapped_blocks;
1129 snap->snapshotted_time = time;
1135 static int __create_snap(struct dm_pool_metadata *pmd,
1136 dm_thin_id dev, dm_thin_id origin)
1139 dm_block_t origin_root;
1140 uint64_t key = origin, dev_key = dev;
1141 struct dm_thin_device *td;
1144 /* check this device is unused */
1145 r = dm_btree_lookup(&pmd->details_info, pmd->details_root,
1150 /* find the mapping tree for the origin */
1151 r = dm_btree_lookup(&pmd->tl_info, pmd->root, &key, &value);
1154 origin_root = le64_to_cpu(value);
1156 /* clone the origin, an inc will do */
1157 dm_tm_inc(pmd->tm, origin_root);
1159 /* insert into the main mapping tree */
1160 value = cpu_to_le64(origin_root);
1161 __dm_bless_for_disk(&value);
1163 r = dm_btree_insert(&pmd->tl_info, pmd->root, &key, &value, &pmd->root);
1165 dm_tm_dec(pmd->tm, origin_root);
1171 r = __open_device(pmd, dev, 1, &td);
1175 r = __set_snapshot_details(pmd, td, origin, pmd->time);
1184 dm_btree_remove(&pmd->tl_info, pmd->root, &key, &pmd->root);
1185 dm_btree_remove(&pmd->details_info, pmd->details_root,
1186 &key, &pmd->details_root);
1190 int dm_pool_create_snap(struct dm_pool_metadata *pmd,
1196 pmd_write_lock(pmd);
1198 r = __create_snap(pmd, dev, origin);
1199 pmd_write_unlock(pmd);
1204 static int __delete_device(struct dm_pool_metadata *pmd, dm_thin_id dev)
1208 struct dm_thin_device *td;
1210 /* TODO: failure should mark the transaction invalid */
1211 r = __open_device(pmd, dev, 0, &td);
1215 if (td->open_count > 1) {
1220 list_del(&td->list);
1222 r = dm_btree_remove(&pmd->details_info, pmd->details_root,
1223 &key, &pmd->details_root);
1227 r = dm_btree_remove(&pmd->tl_info, pmd->root, &key, &pmd->root);
1234 int dm_pool_delete_thin_device(struct dm_pool_metadata *pmd,
1239 pmd_write_lock(pmd);
1241 r = __delete_device(pmd, dev);
1242 pmd_write_unlock(pmd);
1247 int dm_pool_set_metadata_transaction_id(struct dm_pool_metadata *pmd,
1248 uint64_t current_id,
1253 pmd_write_lock(pmd);
1258 if (pmd->trans_id != current_id) {
1259 DMERR("mismatched transaction id");
1263 pmd->trans_id = new_id;
1267 pmd_write_unlock(pmd);
1272 int dm_pool_get_metadata_transaction_id(struct dm_pool_metadata *pmd,
1277 down_read(&pmd->root_lock);
1278 if (!pmd->fail_io) {
1279 *result = pmd->trans_id;
1282 up_read(&pmd->root_lock);
1287 static int __reserve_metadata_snap(struct dm_pool_metadata *pmd)
1290 struct thin_disk_superblock *disk_super;
1291 struct dm_block *copy, *sblock;
1292 dm_block_t held_root;
1295 * We commit to ensure the btree roots which we increment in a
1296 * moment are up to date.
1298 r = __commit_transaction(pmd);
1300 DMWARN("%s: __commit_transaction() failed, error = %d",
1306 * Copy the superblock.
1308 dm_sm_inc_block(pmd->metadata_sm, THIN_SUPERBLOCK_LOCATION);
1309 r = dm_tm_shadow_block(pmd->tm, THIN_SUPERBLOCK_LOCATION,
1310 &sb_validator, ©, &inc);
1316 held_root = dm_block_location(copy);
1317 disk_super = dm_block_data(copy);
1319 if (le64_to_cpu(disk_super->held_root)) {
1320 DMWARN("Pool metadata snapshot already exists: release this before taking another.");
1322 dm_tm_dec(pmd->tm, held_root);
1323 dm_tm_unlock(pmd->tm, copy);
1328 * Wipe the spacemap since we're not publishing this.
1330 memset(&disk_super->data_space_map_root, 0,
1331 sizeof(disk_super->data_space_map_root));
1332 memset(&disk_super->metadata_space_map_root, 0,
1333 sizeof(disk_super->metadata_space_map_root));
1336 * Increment the data structures that need to be preserved.
1338 dm_tm_inc(pmd->tm, le64_to_cpu(disk_super->data_mapping_root));
1339 dm_tm_inc(pmd->tm, le64_to_cpu(disk_super->device_details_root));
1340 dm_tm_unlock(pmd->tm, copy);
1343 * Write the held root into the superblock.
1345 r = superblock_lock(pmd, &sblock);
1347 dm_tm_dec(pmd->tm, held_root);
1351 disk_super = dm_block_data(sblock);
1352 disk_super->held_root = cpu_to_le64(held_root);
1353 dm_bm_unlock(sblock);
1357 int dm_pool_reserve_metadata_snap(struct dm_pool_metadata *pmd)
1361 pmd_write_lock(pmd);
1363 r = __reserve_metadata_snap(pmd);
1364 pmd_write_unlock(pmd);
1369 static int __release_metadata_snap(struct dm_pool_metadata *pmd)
1372 struct thin_disk_superblock *disk_super;
1373 struct dm_block *sblock, *copy;
1374 dm_block_t held_root;
1376 r = superblock_lock(pmd, &sblock);
1380 disk_super = dm_block_data(sblock);
1381 held_root = le64_to_cpu(disk_super->held_root);
1382 disk_super->held_root = cpu_to_le64(0);
1384 dm_bm_unlock(sblock);
1387 DMWARN("No pool metadata snapshot found: nothing to release.");
1391 r = dm_tm_read_lock(pmd->tm, held_root, &sb_validator, ©);
1395 disk_super = dm_block_data(copy);
1396 dm_btree_del(&pmd->info, le64_to_cpu(disk_super->data_mapping_root));
1397 dm_btree_del(&pmd->details_info, le64_to_cpu(disk_super->device_details_root));
1398 dm_sm_dec_block(pmd->metadata_sm, held_root);
1400 dm_tm_unlock(pmd->tm, copy);
1405 int dm_pool_release_metadata_snap(struct dm_pool_metadata *pmd)
1409 pmd_write_lock(pmd);
1411 r = __release_metadata_snap(pmd);
1412 pmd_write_unlock(pmd);
1417 static int __get_metadata_snap(struct dm_pool_metadata *pmd,
1421 struct thin_disk_superblock *disk_super;
1422 struct dm_block *sblock;
1424 r = dm_bm_read_lock(pmd->bm, THIN_SUPERBLOCK_LOCATION,
1425 &sb_validator, &sblock);
1429 disk_super = dm_block_data(sblock);
1430 *result = le64_to_cpu(disk_super->held_root);
1432 dm_bm_unlock(sblock);
1437 int dm_pool_get_metadata_snap(struct dm_pool_metadata *pmd,
1442 down_read(&pmd->root_lock);
1444 r = __get_metadata_snap(pmd, result);
1445 up_read(&pmd->root_lock);
1450 int dm_pool_open_thin_device(struct dm_pool_metadata *pmd, dm_thin_id dev,
1451 struct dm_thin_device **td)
1455 pmd_write_lock_in_core(pmd);
1457 r = __open_device(pmd, dev, 0, td);
1458 pmd_write_unlock(pmd);
1463 int dm_pool_close_thin_device(struct dm_thin_device *td)
1465 pmd_write_lock_in_core(td->pmd);
1467 pmd_write_unlock(td->pmd);
1472 dm_thin_id dm_thin_dev_id(struct dm_thin_device *td)
1478 * Check whether @time (of block creation) is older than @td's last snapshot.
1479 * If so then the associated block is shared with the last snapshot device.
1480 * Any block on a device created *after* the device last got snapshotted is
1481 * necessarily not shared.
1483 static bool __snapshotted_since(struct dm_thin_device *td, uint32_t time)
1485 return td->snapshotted_time > time;
1488 static void unpack_lookup_result(struct dm_thin_device *td, __le64 value,
1489 struct dm_thin_lookup_result *result)
1491 uint64_t block_time = 0;
1492 dm_block_t exception_block;
1493 uint32_t exception_time;
1495 block_time = le64_to_cpu(value);
1496 unpack_block_time(block_time, &exception_block, &exception_time);
1497 result->block = exception_block;
1498 result->shared = __snapshotted_since(td, exception_time);
1501 static int __find_block(struct dm_thin_device *td, dm_block_t block,
1502 int can_issue_io, struct dm_thin_lookup_result *result)
1506 struct dm_pool_metadata *pmd = td->pmd;
1507 dm_block_t keys[2] = { td->id, block };
1508 struct dm_btree_info *info;
1513 info = &pmd->nb_info;
1515 r = dm_btree_lookup(info, pmd->root, keys, &value);
1517 unpack_lookup_result(td, value, result);
1522 int dm_thin_find_block(struct dm_thin_device *td, dm_block_t block,
1523 int can_issue_io, struct dm_thin_lookup_result *result)
1526 struct dm_pool_metadata *pmd = td->pmd;
1528 down_read(&pmd->root_lock);
1530 up_read(&pmd->root_lock);
1534 r = __find_block(td, block, can_issue_io, result);
1536 up_read(&pmd->root_lock);
1540 static int __find_next_mapped_block(struct dm_thin_device *td, dm_block_t block,
1542 struct dm_thin_lookup_result *result)
1546 struct dm_pool_metadata *pmd = td->pmd;
1547 dm_block_t keys[2] = { td->id, block };
1549 r = dm_btree_lookup_next(&pmd->info, pmd->root, keys, vblock, &value);
1551 unpack_lookup_result(td, value, result);
1556 static int __find_mapped_range(struct dm_thin_device *td,
1557 dm_block_t begin, dm_block_t end,
1558 dm_block_t *thin_begin, dm_block_t *thin_end,
1559 dm_block_t *pool_begin, bool *maybe_shared)
1562 dm_block_t pool_end;
1563 struct dm_thin_lookup_result lookup;
1568 r = __find_next_mapped_block(td, begin, &begin, &lookup);
1575 *thin_begin = begin;
1576 *pool_begin = lookup.block;
1577 *maybe_shared = lookup.shared;
1580 pool_end = *pool_begin + 1;
1581 while (begin != end) {
1582 r = __find_block(td, begin, true, &lookup);
1590 if ((lookup.block != pool_end) ||
1591 (lookup.shared != *maybe_shared))
1602 int dm_thin_find_mapped_range(struct dm_thin_device *td,
1603 dm_block_t begin, dm_block_t end,
1604 dm_block_t *thin_begin, dm_block_t *thin_end,
1605 dm_block_t *pool_begin, bool *maybe_shared)
1608 struct dm_pool_metadata *pmd = td->pmd;
1610 down_read(&pmd->root_lock);
1611 if (!pmd->fail_io) {
1612 r = __find_mapped_range(td, begin, end, thin_begin, thin_end,
1613 pool_begin, maybe_shared);
1615 up_read(&pmd->root_lock);
1620 static int __insert(struct dm_thin_device *td, dm_block_t block,
1621 dm_block_t data_block)
1625 struct dm_pool_metadata *pmd = td->pmd;
1626 dm_block_t keys[2] = { td->id, block };
1628 value = cpu_to_le64(pack_block_time(data_block, pmd->time));
1629 __dm_bless_for_disk(&value);
1631 r = dm_btree_insert_notify(&pmd->info, pmd->root, keys, &value,
1632 &pmd->root, &inserted);
1638 td->mapped_blocks++;
1643 int dm_thin_insert_block(struct dm_thin_device *td, dm_block_t block,
1644 dm_block_t data_block)
1648 pmd_write_lock(td->pmd);
1649 if (!td->pmd->fail_io)
1650 r = __insert(td, block, data_block);
1651 pmd_write_unlock(td->pmd);
1656 static int __remove(struct dm_thin_device *td, dm_block_t block)
1659 struct dm_pool_metadata *pmd = td->pmd;
1660 dm_block_t keys[2] = { td->id, block };
1662 r = dm_btree_remove(&pmd->info, pmd->root, keys, &pmd->root);
1666 td->mapped_blocks--;
1672 static int __remove_range(struct dm_thin_device *td, dm_block_t begin, dm_block_t end)
1675 unsigned count, total_count = 0;
1676 struct dm_pool_metadata *pmd = td->pmd;
1677 dm_block_t keys[1] = { td->id };
1679 dm_block_t mapping_root;
1682 * Find the mapping tree
1684 r = dm_btree_lookup(&pmd->tl_info, pmd->root, keys, &value);
1689 * Remove from the mapping tree, taking care to inc the
1690 * ref count so it doesn't get deleted.
1692 mapping_root = le64_to_cpu(value);
1693 dm_tm_inc(pmd->tm, mapping_root);
1694 r = dm_btree_remove(&pmd->tl_info, pmd->root, keys, &pmd->root);
1699 * Remove leaves stops at the first unmapped entry, so we have to
1700 * loop round finding mapped ranges.
1702 while (begin < end) {
1703 r = dm_btree_lookup_next(&pmd->bl_info, mapping_root, &begin, &begin, &value);
1713 r = dm_btree_remove_leaves(&pmd->bl_info, mapping_root, &begin, end, &mapping_root, &count);
1717 total_count += count;
1720 td->mapped_blocks -= total_count;
1724 * Reinsert the mapping tree.
1726 value = cpu_to_le64(mapping_root);
1727 __dm_bless_for_disk(&value);
1728 return dm_btree_insert(&pmd->tl_info, pmd->root, keys, &value, &pmd->root);
1731 int dm_thin_remove_block(struct dm_thin_device *td, dm_block_t block)
1735 pmd_write_lock(td->pmd);
1736 if (!td->pmd->fail_io)
1737 r = __remove(td, block);
1738 pmd_write_unlock(td->pmd);
1743 int dm_thin_remove_range(struct dm_thin_device *td,
1744 dm_block_t begin, dm_block_t end)
1748 pmd_write_lock(td->pmd);
1749 if (!td->pmd->fail_io)
1750 r = __remove_range(td, begin, end);
1751 pmd_write_unlock(td->pmd);
1756 int dm_pool_block_is_shared(struct dm_pool_metadata *pmd, dm_block_t b, bool *result)
1761 down_read(&pmd->root_lock);
1762 r = dm_sm_get_count(pmd->data_sm, b, &ref_count);
1764 *result = (ref_count > 1);
1765 up_read(&pmd->root_lock);
1770 int dm_pool_inc_data_range(struct dm_pool_metadata *pmd, dm_block_t b, dm_block_t e)
1774 pmd_write_lock(pmd);
1775 for (; b != e; b++) {
1776 r = dm_sm_inc_block(pmd->data_sm, b);
1780 pmd_write_unlock(pmd);
1785 int dm_pool_dec_data_range(struct dm_pool_metadata *pmd, dm_block_t b, dm_block_t e)
1789 pmd_write_lock(pmd);
1790 for (; b != e; b++) {
1791 r = dm_sm_dec_block(pmd->data_sm, b);
1795 pmd_write_unlock(pmd);
1800 bool dm_thin_changed_this_transaction(struct dm_thin_device *td)
1804 down_read(&td->pmd->root_lock);
1806 up_read(&td->pmd->root_lock);
1811 bool dm_pool_changed_this_transaction(struct dm_pool_metadata *pmd)
1814 struct dm_thin_device *td, *tmp;
1816 down_read(&pmd->root_lock);
1817 list_for_each_entry_safe(td, tmp, &pmd->thin_devices, list) {
1823 up_read(&pmd->root_lock);
1828 bool dm_thin_aborted_changes(struct dm_thin_device *td)
1832 down_read(&td->pmd->root_lock);
1833 r = td->aborted_with_changes;
1834 up_read(&td->pmd->root_lock);
1839 int dm_pool_alloc_data_block(struct dm_pool_metadata *pmd, dm_block_t *result)
1843 pmd_write_lock(pmd);
1845 r = dm_sm_new_block(pmd->data_sm, result);
1846 pmd_write_unlock(pmd);
1851 int dm_pool_commit_metadata(struct dm_pool_metadata *pmd)
1856 * Care is taken to not have commit be what
1857 * triggers putting the thin-pool in-service.
1859 pmd_write_lock_in_core(pmd);
1863 r = __commit_transaction(pmd);
1868 * Open the next transaction.
1870 r = __begin_transaction(pmd);
1872 pmd_write_unlock(pmd);
1876 static void __set_abort_with_changes_flags(struct dm_pool_metadata *pmd)
1878 struct dm_thin_device *td;
1880 list_for_each_entry(td, &pmd->thin_devices, list)
1881 td->aborted_with_changes = td->changed;
1884 int dm_pool_abort_metadata(struct dm_pool_metadata *pmd)
1887 struct dm_block_manager *old_bm = NULL, *new_bm = NULL;
1889 /* fail_io is double-checked with pmd->root_lock held below */
1890 if (unlikely(pmd->fail_io))
1894 * Replacement block manager (new_bm) is created and old_bm destroyed outside of
1895 * pmd root_lock to avoid ABBA deadlock that would result (due to life-cycle of
1896 * shrinker associated with the block manager's bufio client vs pmd root_lock).
1897 * - must take shrinker_rwsem without holding pmd->root_lock
1899 new_bm = dm_block_manager_create(pmd->bdev, THIN_METADATA_BLOCK_SIZE << SECTOR_SHIFT,
1900 THIN_MAX_CONCURRENT_LOCKS);
1902 pmd_write_lock(pmd);
1904 pmd_write_unlock(pmd);
1908 __set_abort_with_changes_flags(pmd);
1909 __destroy_persistent_data_objects(pmd, false);
1911 if (IS_ERR(new_bm)) {
1912 DMERR("could not create block manager during abort");
1914 r = PTR_ERR(new_bm);
1919 r = __open_or_format_metadata(pmd, false);
1927 pmd->fail_io = true;
1928 pmd_write_unlock(pmd);
1929 dm_block_manager_destroy(old_bm);
1931 if (new_bm && !IS_ERR(new_bm))
1932 dm_block_manager_destroy(new_bm);
1937 int dm_pool_get_free_block_count(struct dm_pool_metadata *pmd, dm_block_t *result)
1941 down_read(&pmd->root_lock);
1943 r = dm_sm_get_nr_free(pmd->data_sm, result);
1944 up_read(&pmd->root_lock);
1949 int dm_pool_get_free_metadata_block_count(struct dm_pool_metadata *pmd,
1954 down_read(&pmd->root_lock);
1956 r = dm_sm_get_nr_free(pmd->metadata_sm, result);
1959 if (*result < pmd->metadata_reserve)
1962 *result -= pmd->metadata_reserve;
1964 up_read(&pmd->root_lock);
1969 int dm_pool_get_metadata_dev_size(struct dm_pool_metadata *pmd,
1974 down_read(&pmd->root_lock);
1976 r = dm_sm_get_nr_blocks(pmd->metadata_sm, result);
1977 up_read(&pmd->root_lock);
1982 int dm_pool_get_data_dev_size(struct dm_pool_metadata *pmd, dm_block_t *result)
1986 down_read(&pmd->root_lock);
1988 r = dm_sm_get_nr_blocks(pmd->data_sm, result);
1989 up_read(&pmd->root_lock);
1994 int dm_thin_get_mapped_count(struct dm_thin_device *td, dm_block_t *result)
1997 struct dm_pool_metadata *pmd = td->pmd;
1999 down_read(&pmd->root_lock);
2000 if (!pmd->fail_io) {
2001 *result = td->mapped_blocks;
2004 up_read(&pmd->root_lock);
2009 static int __highest_block(struct dm_thin_device *td, dm_block_t *result)
2013 dm_block_t thin_root;
2014 struct dm_pool_metadata *pmd = td->pmd;
2016 r = dm_btree_lookup(&pmd->tl_info, pmd->root, &td->id, &value_le);
2020 thin_root = le64_to_cpu(value_le);
2022 return dm_btree_find_highest_key(&pmd->bl_info, thin_root, result);
2025 int dm_thin_get_highest_mapped_block(struct dm_thin_device *td,
2029 struct dm_pool_metadata *pmd = td->pmd;
2031 down_read(&pmd->root_lock);
2033 r = __highest_block(td, result);
2034 up_read(&pmd->root_lock);
2039 static int __resize_space_map(struct dm_space_map *sm, dm_block_t new_count)
2042 dm_block_t old_count;
2044 r = dm_sm_get_nr_blocks(sm, &old_count);
2048 if (new_count == old_count)
2051 if (new_count < old_count) {
2052 DMERR("cannot reduce size of space map");
2056 return dm_sm_extend(sm, new_count - old_count);
2059 int dm_pool_resize_data_dev(struct dm_pool_metadata *pmd, dm_block_t new_count)
2063 pmd_write_lock(pmd);
2065 r = __resize_space_map(pmd->data_sm, new_count);
2066 pmd_write_unlock(pmd);
2071 int dm_pool_resize_metadata_dev(struct dm_pool_metadata *pmd, dm_block_t new_count)
2075 pmd_write_lock(pmd);
2076 if (!pmd->fail_io) {
2077 r = __resize_space_map(pmd->metadata_sm, new_count);
2079 __set_metadata_reserve(pmd);
2081 pmd_write_unlock(pmd);
2086 void dm_pool_metadata_read_only(struct dm_pool_metadata *pmd)
2088 pmd_write_lock_in_core(pmd);
2089 dm_bm_set_read_only(pmd->bm);
2090 pmd_write_unlock(pmd);
2093 void dm_pool_metadata_read_write(struct dm_pool_metadata *pmd)
2095 pmd_write_lock_in_core(pmd);
2096 dm_bm_set_read_write(pmd->bm);
2097 pmd_write_unlock(pmd);
2100 int dm_pool_register_metadata_threshold(struct dm_pool_metadata *pmd,
2101 dm_block_t threshold,
2102 dm_sm_threshold_fn fn,
2107 pmd_write_lock_in_core(pmd);
2108 if (!pmd->fail_io) {
2109 r = dm_sm_register_threshold_callback(pmd->metadata_sm,
2110 threshold, fn, context);
2112 pmd_write_unlock(pmd);
2117 void dm_pool_register_pre_commit_callback(struct dm_pool_metadata *pmd,
2118 dm_pool_pre_commit_fn fn,
2121 pmd_write_lock_in_core(pmd);
2122 pmd->pre_commit_fn = fn;
2123 pmd->pre_commit_context = context;
2124 pmd_write_unlock(pmd);
2127 int dm_pool_metadata_set_needs_check(struct dm_pool_metadata *pmd)
2130 struct dm_block *sblock;
2131 struct thin_disk_superblock *disk_super;
2133 pmd_write_lock(pmd);
2137 pmd->flags |= THIN_METADATA_NEEDS_CHECK_FLAG;
2139 r = superblock_lock(pmd, &sblock);
2141 DMERR("couldn't lock superblock");
2145 disk_super = dm_block_data(sblock);
2146 disk_super->flags = cpu_to_le32(pmd->flags);
2148 dm_bm_unlock(sblock);
2150 pmd_write_unlock(pmd);
2154 bool dm_pool_metadata_needs_check(struct dm_pool_metadata *pmd)
2158 down_read(&pmd->root_lock);
2159 needs_check = pmd->flags & THIN_METADATA_NEEDS_CHECK_FLAG;
2160 up_read(&pmd->root_lock);
2165 void dm_pool_issue_prefetches(struct dm_pool_metadata *pmd)
2167 down_read(&pmd->root_lock);
2169 dm_tm_issue_prefetches(pmd->tm);
2170 up_read(&pmd->root_lock);