diff options
Diffstat (limited to 'drivers/md/persistent-data')
| -rw-r--r-- | drivers/md/persistent-data/dm-space-map-disk.c | 3 | ||||
| -rw-r--r-- | drivers/md/persistent-data/dm-space-map-metadata.c | 127 | ||||
| -rw-r--r-- | drivers/md/persistent-data/dm-space-map.h | 23 |
3 files changed, 140 insertions, 13 deletions
diff --git a/drivers/md/persistent-data/dm-space-map-disk.c b/drivers/md/persistent-data/dm-space-map-disk.c index f6d29e614ab7..e735a6d5a793 100644 --- a/drivers/md/persistent-data/dm-space-map-disk.c +++ b/drivers/md/persistent-data/dm-space-map-disk.c @@ -248,7 +248,8 @@ static struct dm_space_map ops = { .new_block = sm_disk_new_block, .commit = sm_disk_commit, .root_size = sm_disk_root_size, - .copy_root = sm_disk_copy_root + .copy_root = sm_disk_copy_root, + .register_threshold_callback = NULL }; struct dm_space_map *dm_sm_disk_create(struct dm_transaction_manager *tm, diff --git a/drivers/md/persistent-data/dm-space-map-metadata.c b/drivers/md/persistent-data/dm-space-map-metadata.c index 906cf3df71af..1c959684caef 100644 --- a/drivers/md/persistent-data/dm-space-map-metadata.c +++ b/drivers/md/persistent-data/dm-space-map-metadata.c @@ -17,6 +17,55 @@ /*----------------------------------------------------------------*/ /* + * An edge triggered threshold. + */ +struct threshold { + bool threshold_set; + bool value_set; + dm_block_t threshold; + dm_block_t current_value; + dm_sm_threshold_fn fn; + void *context; +}; + +static void threshold_init(struct threshold *t) +{ + t->threshold_set = false; + t->value_set = false; +} + +static void set_threshold(struct threshold *t, dm_block_t value, + dm_sm_threshold_fn fn, void *context) +{ + t->threshold_set = true; + t->threshold = value; + t->fn = fn; + t->context = context; +} + +static bool below_threshold(struct threshold *t, dm_block_t value) +{ + return t->threshold_set && value <= t->threshold; +} + +static bool threshold_already_triggered(struct threshold *t) +{ + return t->value_set && below_threshold(t, t->current_value); +} + +static void check_threshold(struct threshold *t, dm_block_t value) +{ + if (below_threshold(t, value) && + !threshold_already_triggered(t)) + t->fn(t->context); + + t->value_set = true; + t->current_value = value; +} + +/*----------------------------------------------------------------*/ + +/* * Space map interface. * * The low level disk format is written using the standard btree and @@ -54,6 +103,8 @@ struct sm_metadata { unsigned allocated_this_transaction; unsigned nr_uncommitted; struct block_op uncommitted[MAX_RECURSIVE_ALLOCATIONS]; + + struct threshold threshold; }; static int add_bop(struct sm_metadata *smm, enum block_op_type type, dm_block_t b) @@ -144,12 +195,6 @@ static void sm_metadata_destroy(struct dm_space_map *sm) kfree(smm); } -static int sm_metadata_extend(struct dm_space_map *sm, dm_block_t extra_blocks) -{ - DMERR("doesn't support extend"); - return -EINVAL; -} - static int sm_metadata_get_nr_blocks(struct dm_space_map *sm, dm_block_t *count) { struct sm_metadata *smm = container_of(sm, struct sm_metadata, sm); @@ -335,9 +380,19 @@ static int sm_metadata_new_block_(struct dm_space_map *sm, dm_block_t *b) static int sm_metadata_new_block(struct dm_space_map *sm, dm_block_t *b) { + dm_block_t count; + struct sm_metadata *smm = container_of(sm, struct sm_metadata, sm); + int r = sm_metadata_new_block_(sm, b); if (r) DMERR("unable to allocate new metadata block"); + + r = sm_metadata_get_nr_free(sm, &count); + if (r) + DMERR("couldn't get free block count"); + + check_threshold(&smm->threshold, count); + return r; } @@ -357,6 +412,18 @@ static int sm_metadata_commit(struct dm_space_map *sm) return 0; } +static int sm_metadata_register_threshold_callback(struct dm_space_map *sm, + dm_block_t threshold, + dm_sm_threshold_fn fn, + void *context) +{ + struct sm_metadata *smm = container_of(sm, struct sm_metadata, sm); + + set_threshold(&smm->threshold, threshold, fn, context); + + return 0; +} + static int sm_metadata_root_size(struct dm_space_map *sm, size_t *result) { *result = sizeof(struct disk_sm_root); @@ -382,6 +449,8 @@ static int sm_metadata_copy_root(struct dm_space_map *sm, void *where_le, size_t return 0; } +static int sm_metadata_extend(struct dm_space_map *sm, dm_block_t extra_blocks); + static struct dm_space_map ops = { .destroy = sm_metadata_destroy, .extend = sm_metadata_extend, @@ -395,7 +464,8 @@ static struct dm_space_map ops = { .new_block = sm_metadata_new_block, .commit = sm_metadata_commit, .root_size = sm_metadata_root_size, - .copy_root = sm_metadata_copy_root + .copy_root = sm_metadata_copy_root, + .register_threshold_callback = sm_metadata_register_threshold_callback }; /*----------------------------------------------------------------*/ @@ -410,7 +480,7 @@ static void sm_bootstrap_destroy(struct dm_space_map *sm) static int sm_bootstrap_extend(struct dm_space_map *sm, dm_block_t extra_blocks) { - DMERR("boostrap doesn't support extend"); + DMERR("bootstrap doesn't support extend"); return -EINVAL; } @@ -450,7 +520,7 @@ static int sm_bootstrap_count_is_more_than_one(struct dm_space_map *sm, static int sm_bootstrap_set_count(struct dm_space_map *sm, dm_block_t b, uint32_t count) { - DMERR("boostrap doesn't support set_count"); + DMERR("bootstrap doesn't support set_count"); return -EINVAL; } @@ -491,7 +561,7 @@ static int sm_bootstrap_commit(struct dm_space_map *sm) static int sm_bootstrap_root_size(struct dm_space_map *sm, size_t *result) { - DMERR("boostrap doesn't support root_size"); + DMERR("bootstrap doesn't support root_size"); return -EINVAL; } @@ -499,7 +569,7 @@ static int sm_bootstrap_root_size(struct dm_space_map *sm, size_t *result) static int sm_bootstrap_copy_root(struct dm_space_map *sm, void *where, size_t max) { - DMERR("boostrap doesn't support copy_root"); + DMERR("bootstrap doesn't support copy_root"); return -EINVAL; } @@ -517,11 +587,42 @@ static struct dm_space_map bootstrap_ops = { .new_block = sm_bootstrap_new_block, .commit = sm_bootstrap_commit, .root_size = sm_bootstrap_root_size, - .copy_root = sm_bootstrap_copy_root + .copy_root = sm_bootstrap_copy_root, + .register_threshold_callback = NULL }; /*----------------------------------------------------------------*/ +static int sm_metadata_extend(struct dm_space_map *sm, dm_block_t extra_blocks) +{ + int r, i; + enum allocation_event ev; + struct sm_metadata *smm = container_of(sm, struct sm_metadata, sm); + dm_block_t old_len = smm->ll.nr_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)); + + /* + * Extend. + */ + r = sm_ll_extend(&smm->ll, extra_blocks); + + /* + * Switch back to normal behaviour. + */ + memcpy(&smm->sm, &ops, sizeof(smm->sm)); + for (i = old_len; !r && i < smm->begin; i++) + r = sm_ll_inc(&smm->ll, i, &ev); + + return r; +} + +/*----------------------------------------------------------------*/ + struct dm_space_map *dm_sm_metadata_init(void) { struct sm_metadata *smm; @@ -549,6 +650,7 @@ int dm_sm_metadata_create(struct dm_space_map *sm, smm->recursion_count = 0; smm->allocated_this_transaction = 0; smm->nr_uncommitted = 0; + threshold_init(&smm->threshold); memcpy(&smm->sm, &bootstrap_ops, sizeof(smm->sm)); @@ -590,6 +692,7 @@ int dm_sm_metadata_open(struct dm_space_map *sm, smm->recursion_count = 0; smm->allocated_this_transaction = 0; smm->nr_uncommitted = 0; + threshold_init(&smm->threshold); memcpy(&smm->old_ll, &smm->ll, sizeof(smm->old_ll)); return 0; diff --git a/drivers/md/persistent-data/dm-space-map.h b/drivers/md/persistent-data/dm-space-map.h index 1cbfc6b1638a..3e6d1153b7c4 100644 --- a/drivers/md/persistent-data/dm-space-map.h +++ b/drivers/md/persistent-data/dm-space-map.h @@ -9,6 +9,8 @@ #include "dm-block-manager.h" +typedef void (*dm_sm_threshold_fn)(void *context); + /* * struct dm_space_map keeps a record of how many times each block in a device * is referenced. It needs to be fixed on disk as part of the transaction. @@ -59,6 +61,15 @@ struct dm_space_map { */ int (*root_size)(struct dm_space_map *sm, size_t *result); int (*copy_root)(struct dm_space_map *sm, void *copy_to_here_le, size_t len); + + /* + * You can register one threshold callback which is edge-triggered + * when the free space in the space map drops below the threshold. + */ + int (*register_threshold_callback)(struct dm_space_map *sm, + dm_block_t threshold, + dm_sm_threshold_fn fn, + void *context); }; /*----------------------------------------------------------------*/ @@ -131,4 +142,16 @@ static inline int dm_sm_copy_root(struct dm_space_map *sm, void *copy_to_here_le return sm->copy_root(sm, copy_to_here_le, len); } +static inline int dm_sm_register_threshold_callback(struct dm_space_map *sm, + dm_block_t threshold, + dm_sm_threshold_fn fn, + void *context) +{ + if (sm->register_threshold_callback) + return sm->register_threshold_callback(sm, threshold, fn, context); + + return -EINVAL; +} + + #endif /* _LINUX_DM_SPACE_MAP_H */ |