diff options
Diffstat (limited to 'drivers/md/persistent-data')
| -rw-r--r-- | drivers/md/persistent-data/Kconfig | 10 | ||||
| -rw-r--r-- | drivers/md/persistent-data/dm-block-manager.c | 2 | ||||
| -rw-r--r-- | drivers/md/persistent-data/dm-btree.c | 33 | ||||
| -rw-r--r-- | drivers/md/persistent-data/dm-btree.h | 8 | ||||
| -rw-r--r-- | drivers/md/persistent-data/dm-space-map-common.c | 6 | ||||
| -rw-r--r-- | drivers/md/persistent-data/dm-space-map-metadata.c | 147 | ||||
| -rw-r--r-- | drivers/md/persistent-data/dm-space-map-metadata.h | 11 |
7 files changed, 180 insertions, 37 deletions
diff --git a/drivers/md/persistent-data/Kconfig b/drivers/md/persistent-data/Kconfig index 19b268795415..0c2dec7aec20 100644 --- a/drivers/md/persistent-data/Kconfig +++ b/drivers/md/persistent-data/Kconfig @@ -6,3 +6,13 @@ config DM_PERSISTENT_DATA ---help--- Library providing immutable on-disk data structure support for device-mapper targets such as the thin provisioning target. + +config DM_DEBUG_BLOCK_STACK_TRACING + boolean "Keep stack trace of persistent data block lock holders" + depends on STACKTRACE_SUPPORT && DM_PERSISTENT_DATA + select STACKTRACE + ---help--- + Enable this for messages that may help debug problems with the + block manager locking used by thin provisioning and caching. + + If unsure, say N. diff --git a/drivers/md/persistent-data/dm-block-manager.c b/drivers/md/persistent-data/dm-block-manager.c index 064a3c271baa..455f79279a16 100644 --- a/drivers/md/persistent-data/dm-block-manager.c +++ b/drivers/md/persistent-data/dm-block-manager.c @@ -104,7 +104,7 @@ static int __check_holder(struct block_lock *lock) for (i = 0; i < MAX_HOLDERS; i++) { if (lock->holders[i] == current) { - DMERR("recursive lock detected in pool metadata"); + DMERR("recursive lock detected in metadata"); #ifdef CONFIG_DM_DEBUG_BLOCK_STACK_TRACING DMERR("previously held here:"); print_stack_trace(lock->traces + i, 4); diff --git a/drivers/md/persistent-data/dm-btree.c b/drivers/md/persistent-data/dm-btree.c index 468e371ee9b2..416060c25709 100644 --- a/drivers/md/persistent-data/dm-btree.c +++ b/drivers/md/persistent-data/dm-btree.c @@ -770,8 +770,8 @@ EXPORT_SYMBOL_GPL(dm_btree_insert_notify); /*----------------------------------------------------------------*/ -static int find_highest_key(struct ro_spine *s, dm_block_t block, - uint64_t *result_key, dm_block_t *next_block) +static int find_key(struct ro_spine *s, dm_block_t block, bool find_highest, + uint64_t *result_key, dm_block_t *next_block) { int i, r; uint32_t flags; @@ -788,7 +788,11 @@ static int find_highest_key(struct ro_spine *s, dm_block_t block, else i--; - *result_key = le64_to_cpu(ro_node(s)->keys[i]); + if (find_highest) + *result_key = le64_to_cpu(ro_node(s)->keys[i]); + else + *result_key = le64_to_cpu(ro_node(s)->keys[0]); + if (next_block || flags & INTERNAL_NODE) block = value64(ro_node(s), i); @@ -799,16 +803,16 @@ static int find_highest_key(struct ro_spine *s, dm_block_t block, return 0; } -int dm_btree_find_highest_key(struct dm_btree_info *info, dm_block_t root, - uint64_t *result_keys) +static int dm_btree_find_key(struct dm_btree_info *info, dm_block_t root, + bool find_highest, uint64_t *result_keys) { int r = 0, count = 0, level; struct ro_spine spine; init_ro_spine(&spine, info); for (level = 0; level < info->levels; level++) { - r = find_highest_key(&spine, root, result_keys + level, - level == info->levels - 1 ? NULL : &root); + r = find_key(&spine, root, find_highest, result_keys + level, + level == info->levels - 1 ? NULL : &root); if (r == -ENODATA) { r = 0; break; @@ -822,8 +826,23 @@ int dm_btree_find_highest_key(struct dm_btree_info *info, dm_block_t root, return r ? r : count; } + +int dm_btree_find_highest_key(struct dm_btree_info *info, dm_block_t root, + uint64_t *result_keys) +{ + return dm_btree_find_key(info, root, true, result_keys); +} EXPORT_SYMBOL_GPL(dm_btree_find_highest_key); +int dm_btree_find_lowest_key(struct dm_btree_info *info, dm_block_t root, + uint64_t *result_keys) +{ + return dm_btree_find_key(info, root, false, result_keys); +} +EXPORT_SYMBOL_GPL(dm_btree_find_lowest_key); + +/*----------------------------------------------------------------*/ + /* * FIXME: We shouldn't use a recursive algorithm when we have limited stack * space. Also this only works for single level trees. diff --git a/drivers/md/persistent-data/dm-btree.h b/drivers/md/persistent-data/dm-btree.h index 8672d159e0b5..dacfc34180b4 100644 --- a/drivers/md/persistent-data/dm-btree.h +++ b/drivers/md/persistent-data/dm-btree.h @@ -137,6 +137,14 @@ int dm_btree_remove(struct dm_btree_info *info, dm_block_t root, /* * Returns < 0 on failure. Otherwise the number of key entries that have * been filled out. Remember trees can have zero entries, and as such have + * no lowest key. + */ +int dm_btree_find_lowest_key(struct dm_btree_info *info, dm_block_t root, + uint64_t *result_keys); + +/* + * Returns < 0 on failure. Otherwise the number of key entries that have + * been filled out. Remember trees can have zero entries, and as such have * no highest key. */ int dm_btree_find_highest_key(struct dm_btree_info *info, dm_block_t root, diff --git a/drivers/md/persistent-data/dm-space-map-common.c b/drivers/md/persistent-data/dm-space-map-common.c index 466a60bbd716..aacbe70c2c2e 100644 --- a/drivers/md/persistent-data/dm-space-map-common.c +++ b/drivers/md/persistent-data/dm-space-map-common.c @@ -245,6 +245,10 @@ int sm_ll_extend(struct ll_disk *ll, dm_block_t extra_blocks) return -EINVAL; } + /* + * We need to set this before the dm_tm_new_block() call below. + */ + ll->nr_blocks = nr_blocks; for (i = old_blocks; i < blocks; i++) { struct dm_block *b; struct disk_index_entry idx; @@ -252,6 +256,7 @@ int sm_ll_extend(struct ll_disk *ll, dm_block_t extra_blocks) r = dm_tm_new_block(ll->tm, &dm_sm_bitmap_validator, &b); if (r < 0) return r; + idx.blocknr = cpu_to_le64(dm_block_location(b)); r = dm_tm_unlock(ll->tm, b); @@ -266,7 +271,6 @@ int sm_ll_extend(struct ll_disk *ll, dm_block_t extra_blocks) return r; } - ll->nr_blocks = nr_blocks; return 0; } diff --git a/drivers/md/persistent-data/dm-space-map-metadata.c b/drivers/md/persistent-data/dm-space-map-metadata.c index 58fc1eef7499..786b689bdfc7 100644 --- a/drivers/md/persistent-data/dm-space-map-metadata.c +++ b/drivers/md/persistent-data/dm-space-map-metadata.c @@ -91,6 +91,69 @@ struct block_op { dm_block_t block; }; +struct bop_ring_buffer { + unsigned begin; + unsigned end; + struct block_op bops[MAX_RECURSIVE_ALLOCATIONS + 1]; +}; + +static void brb_init(struct bop_ring_buffer *brb) +{ + brb->begin = 0; + brb->end = 0; +} + +static bool brb_empty(struct bop_ring_buffer *brb) +{ + return brb->begin == brb->end; +} + +static unsigned brb_next(struct bop_ring_buffer *brb, unsigned old) +{ + unsigned r = old + 1; + return (r >= (sizeof(brb->bops) / sizeof(*brb->bops))) ? 0 : r; +} + +static int brb_push(struct bop_ring_buffer *brb, + enum block_op_type type, dm_block_t b) +{ + struct block_op *bop; + unsigned next = brb_next(brb, brb->end); + + /* + * We don't allow the last bop to be filled, this way we can + * differentiate between full and empty. + */ + if (next == brb->begin) + return -ENOMEM; + + bop = brb->bops + brb->end; + bop->type = type; + bop->block = b; + + brb->end = next; + + return 0; +} + +static int brb_pop(struct bop_ring_buffer *brb, struct block_op *result) +{ + struct block_op *bop; + + if (brb_empty(brb)) + return -ENODATA; + + bop = brb->bops + brb->begin; + result->type = bop->type; + result->block = bop->block; + + brb->begin = brb_next(brb, brb->begin); + + return 0; +} + +/*----------------------------------------------------------------*/ + struct sm_metadata { struct dm_space_map sm; @@ -101,25 +164,20 @@ struct sm_metadata { unsigned recursion_count; unsigned allocated_this_transaction; - unsigned nr_uncommitted; - struct block_op uncommitted[MAX_RECURSIVE_ALLOCATIONS]; + struct bop_ring_buffer uncommitted; struct threshold threshold; }; static int add_bop(struct sm_metadata *smm, enum block_op_type type, dm_block_t b) { - struct block_op *op; + int r = brb_push(&smm->uncommitted, type, b); - if (smm->nr_uncommitted == MAX_RECURSIVE_ALLOCATIONS) { + if (r) { DMERR("too many recursive allocations"); return -ENOMEM; } - op = smm->uncommitted + smm->nr_uncommitted++; - op->type = type; - op->block = b; - return 0; } @@ -158,11 +216,17 @@ static int out(struct sm_metadata *smm) return -ENOMEM; } - if (smm->recursion_count == 1 && smm->nr_uncommitted) { - while (smm->nr_uncommitted && !r) { - smm->nr_uncommitted--; - r = commit_bop(smm, smm->uncommitted + - smm->nr_uncommitted); + if (smm->recursion_count == 1) { + while (!brb_empty(&smm->uncommitted)) { + struct block_op bop; + + r = brb_pop(&smm->uncommitted, &bop); + if (r) { + DMERR("bug in bop ring buffer"); + break; + } + + r = commit_bop(smm, &bop); if (r) break; } @@ -217,7 +281,8 @@ static int sm_metadata_get_nr_free(struct dm_space_map *sm, dm_block_t *count) static int sm_metadata_get_count(struct dm_space_map *sm, dm_block_t b, uint32_t *result) { - int r, i; + int r; + unsigned i; struct sm_metadata *smm = container_of(sm, struct sm_metadata, sm); unsigned adjustment = 0; @@ -225,8 +290,10 @@ static int sm_metadata_get_count(struct dm_space_map *sm, dm_block_t b, * We may have some uncommitted adjustments to add. This list * should always be really short. */ - for (i = 0; i < smm->nr_uncommitted; i++) { - struct block_op *op = smm->uncommitted + i; + for (i = smm->uncommitted.begin; + i != smm->uncommitted.end; + i = brb_next(&smm->uncommitted, i)) { + struct block_op *op = smm->uncommitted.bops + i; if (op->block != b) continue; @@ -254,7 +321,8 @@ static int sm_metadata_get_count(struct dm_space_map *sm, dm_block_t b, static int sm_metadata_count_is_more_than_one(struct dm_space_map *sm, dm_block_t b, int *result) { - int r, i, adjustment = 0; + int r, adjustment = 0; + unsigned i; struct sm_metadata *smm = container_of(sm, struct sm_metadata, sm); uint32_t rc; @@ -262,8 +330,11 @@ static int sm_metadata_count_is_more_than_one(struct dm_space_map *sm, * We may have some uncommitted adjustments to add. This list * should always be really short. */ - for (i = 0; i < smm->nr_uncommitted; i++) { - struct block_op *op = smm->uncommitted + i; + for (i = smm->uncommitted.begin; + i != smm->uncommitted.end; + i = brb_next(&smm->uncommitted, i)) { + + struct block_op *op = smm->uncommitted.bops + i; if (op->block != b) continue; @@ -385,13 +456,13 @@ static int sm_metadata_new_block(struct dm_space_map *sm, dm_block_t *b) int r = sm_metadata_new_block_(sm, b); if (r) { - DMERR("unable to allocate new metadata block"); + DMERR_LIMIT("unable to allocate new metadata block"); return r; } r = sm_metadata_get_nr_free(sm, &count); if (r) { - DMERR("couldn't get free block count"); + DMERR_LIMIT("couldn't get free block count"); return r; } @@ -608,20 +679,38 @@ static int sm_metadata_extend(struct dm_space_map *sm, dm_block_t extra_blocks) * Flick into a mode where all blocks get allocated in the new area. */ smm->begin = old_len; - memcpy(&smm->sm, &bootstrap_ops, sizeof(smm->sm)); + memcpy(sm, &bootstrap_ops, sizeof(*sm)); /* * Extend. */ r = sm_ll_extend(&smm->ll, extra_blocks); + if (r) + goto out; /* - * Switch back to normal behaviour. + * We repeatedly increment then commit until the commit doesn't + * allocate any new blocks. */ - memcpy(&smm->sm, &ops, sizeof(smm->sm)); - for (i = old_len; !r && i < smm->begin; i++) - r = sm_ll_inc(&smm->ll, i, &ev); + do { + for (i = old_len; !r && i < smm->begin; i++) { + r = sm_ll_inc(&smm->ll, i, &ev); + if (r) + goto out; + } + old_len = smm->begin; + + r = sm_ll_commit(&smm->ll); + if (r) + goto out; + + } while (old_len != smm->begin); +out: + /* + * Switch back to normal behaviour. + */ + memcpy(sm, &ops, sizeof(*sm)); return r; } @@ -653,7 +742,7 @@ int dm_sm_metadata_create(struct dm_space_map *sm, smm->begin = superblock + 1; smm->recursion_count = 0; smm->allocated_this_transaction = 0; - smm->nr_uncommitted = 0; + brb_init(&smm->uncommitted); threshold_init(&smm->threshold); memcpy(&smm->sm, &bootstrap_ops, sizeof(smm->sm)); @@ -662,6 +751,8 @@ int dm_sm_metadata_create(struct dm_space_map *sm, if (r) return r; + if (nr_blocks > DM_SM_METADATA_MAX_BLOCKS) + nr_blocks = DM_SM_METADATA_MAX_BLOCKS; r = sm_ll_extend(&smm->ll, nr_blocks); if (r) return r; @@ -695,7 +786,7 @@ int dm_sm_metadata_open(struct dm_space_map *sm, smm->begin = 0; smm->recursion_count = 0; smm->allocated_this_transaction = 0; - smm->nr_uncommitted = 0; + brb_init(&smm->uncommitted); threshold_init(&smm->threshold); memcpy(&smm->old_ll, &smm->ll, sizeof(smm->old_ll)); diff --git a/drivers/md/persistent-data/dm-space-map-metadata.h b/drivers/md/persistent-data/dm-space-map-metadata.h index 39bba0801cf2..64df923974d8 100644 --- a/drivers/md/persistent-data/dm-space-map-metadata.h +++ b/drivers/md/persistent-data/dm-space-map-metadata.h @@ -9,6 +9,17 @@ #include "dm-transaction-manager.h" +#define DM_SM_METADATA_BLOCK_SIZE (4096 >> SECTOR_SHIFT) + +/* + * The metadata device is currently limited in size. + * + * We have one block of index, which can hold 255 index entries. Each + * index entry contains allocation info about ~16k metadata blocks. + */ +#define DM_SM_METADATA_MAX_BLOCKS (255 * ((1 << 14) - 64)) +#define DM_SM_METADATA_MAX_SECTORS (DM_SM_METADATA_MAX_BLOCKS * DM_SM_METADATA_BLOCK_SIZE) + /* * Unfortunately we have to use two-phase construction due to the cycle * between the tm and sm. |