diff options
Diffstat (limited to 'drivers/md')
-rw-r--r-- | drivers/md/Kconfig | 22 | ||||
-rw-r--r-- | drivers/md/bitmap.c | 4 | ||||
-rw-r--r-- | drivers/md/dm-cache-metadata.c | 104 | ||||
-rw-r--r-- | drivers/md/dm-cache-metadata.h | 5 | ||||
-rw-r--r-- | drivers/md/dm-cache-policy-internal.h | 7 | ||||
-rw-r--r-- | drivers/md/dm-cache-policy-mq.c | 681 | ||||
-rw-r--r-- | drivers/md/dm-cache-policy.c | 4 | ||||
-rw-r--r-- | drivers/md/dm-cache-policy.h | 21 | ||||
-rw-r--r-- | drivers/md/dm-cache-target.c | 687 | ||||
-rw-r--r-- | drivers/md/dm-crypt.c | 216 | ||||
-rw-r--r-- | drivers/md/dm-ioctl.c | 36 | ||||
-rw-r--r-- | drivers/md/dm-mpath.c | 34 | ||||
-rw-r--r-- | drivers/md/dm-table.c | 23 | ||||
-rw-r--r-- | drivers/md/dm.c | 47 | ||||
-rw-r--r-- | drivers/md/dm.h | 13 | ||||
-rw-r--r-- | drivers/md/md.c | 2 | ||||
-rw-r--r-- | drivers/md/md.h | 2 | ||||
-rw-r--r-- | drivers/md/persistent-data/dm-array.c | 5 | ||||
-rw-r--r-- | drivers/md/persistent-data/dm-space-map-disk.c | 18 | ||||
-rw-r--r-- | drivers/md/raid5.c | 14 |
20 files changed, 1471 insertions, 474 deletions
diff --git a/drivers/md/Kconfig b/drivers/md/Kconfig index 30b426e..f2ccbc3 100644 --- a/drivers/md/Kconfig +++ b/drivers/md/Kconfig @@ -297,6 +297,17 @@ config DM_MIRROR Allow volume managers to mirror logical volumes, also needed for live data migration tools such as 'pvmove'. +config DM_LOG_USERSPACE + tristate "Mirror userspace logging" + depends on DM_MIRROR && NET + select CONNECTOR + ---help--- + The userspace logging module provides a mechanism for + relaying the dm-dirty-log API to userspace. Log designs + which are more suited to userspace implementation (e.g. + shared storage logs) or experimental logs can be implemented + by leveraging this framework. + config DM_RAID tristate "RAID 1/4/5/6/10 target" depends on BLK_DEV_DM @@ -323,17 +334,6 @@ config DM_RAID RAID-5, RAID-6 distributes the syndromes across the drives in one of the available parity distribution methods. -config DM_LOG_USERSPACE - tristate "Mirror userspace logging" - depends on DM_MIRROR && NET - select CONNECTOR - ---help--- - The userspace logging module provides a mechanism for - relaying the dm-dirty-log API to userspace. Log designs - which are more suited to userspace implementation (e.g. - shared storage logs) or experimental logs can be implemented - by leveraging this framework. - config DM_ZERO tristate "Zero target" depends on BLK_DEV_DM diff --git a/drivers/md/bitmap.c b/drivers/md/bitmap.c index a7fd821..12dc29b 100644 --- a/drivers/md/bitmap.c +++ b/drivers/md/bitmap.c @@ -1654,9 +1654,9 @@ int bitmap_create(struct mddev *mddev) bitmap->mddev = mddev; if (mddev->kobj.sd) - bm = sysfs_get_dirent(mddev->kobj.sd, NULL, "bitmap"); + bm = sysfs_get_dirent(mddev->kobj.sd, "bitmap"); if (bm) { - bitmap->sysfs_can_clear = sysfs_get_dirent(bm, NULL, "can_clear"); + bitmap->sysfs_can_clear = sysfs_get_dirent(bm, "can_clear"); sysfs_put(bm); } else bitmap->sysfs_can_clear = NULL; diff --git a/drivers/md/dm-cache-metadata.c b/drivers/md/dm-cache-metadata.c index 1af7255..9ef0752 100644 --- a/drivers/md/dm-cache-metadata.c +++ b/drivers/md/dm-cache-metadata.c @@ -20,7 +20,13 @@ #define CACHE_SUPERBLOCK_MAGIC 06142003 #define CACHE_SUPERBLOCK_LOCATION 0 -#define CACHE_VERSION 1 + +/* + * defines a range of metadata versions that this module can handle. + */ +#define MIN_CACHE_VERSION 1 +#define MAX_CACHE_VERSION 1 + #define CACHE_METADATA_CACHE_SIZE 64 /* @@ -134,6 +140,18 @@ static void sb_prepare_for_write(struct dm_block_validator *v, SUPERBLOCK_CSUM_XOR)); } +static int check_metadata_version(struct cache_disk_superblock *disk_super) +{ + uint32_t metadata_version = le32_to_cpu(disk_super->version); + if (metadata_version < MIN_CACHE_VERSION || metadata_version > MAX_CACHE_VERSION) { + DMERR("Cache metadata version %u found, but only versions between %u and %u supported.", + metadata_version, MIN_CACHE_VERSION, MAX_CACHE_VERSION); + return -EINVAL; + } + + return 0; +} + static int sb_check(struct dm_block_validator *v, struct dm_block *b, size_t sb_block_size) @@ -164,7 +182,7 @@ static int sb_check(struct dm_block_validator *v, return -EILSEQ; } - return 0; + return check_metadata_version(disk_super); } static struct dm_block_validator sb_validator = { @@ -198,7 +216,7 @@ static int superblock_lock(struct dm_cache_metadata *cmd, /*----------------------------------------------------------------*/ -static int __superblock_all_zeroes(struct dm_block_manager *bm, int *result) +static int __superblock_all_zeroes(struct dm_block_manager *bm, bool *result) { int r; unsigned i; @@ -214,10 +232,10 @@ static int __superblock_all_zeroes(struct dm_block_manager *bm, int *result) return r; data_le = dm_block_data(b); - *result = 1; + *result = true; for (i = 0; i < sb_block_size; i++) { if (data_le[i] != zero) { - *result = 0; + *result = false; break; } } @@ -270,7 +288,7 @@ static int __write_initial_superblock(struct dm_cache_metadata *cmd) disk_super->flags = 0; memset(disk_super->uuid, 0, sizeof(disk_super->uuid)); disk_super->magic = cpu_to_le64(CACHE_SUPERBLOCK_MAGIC); - disk_super->version = cpu_to_le32(CACHE_VERSION); + disk_super->version = cpu_to_le32(MAX_CACHE_VERSION); memset(disk_super->policy_name, 0, sizeof(disk_super->policy_name)); memset(disk_super->policy_version, 0, sizeof(disk_super->policy_version)); disk_super->policy_hint_size = 0; @@ -411,7 +429,8 @@ bad: static int __open_or_format_metadata(struct dm_cache_metadata *cmd, bool format_device) { - int r, unformatted; + int r; + bool unformatted = false; r = __superblock_all_zeroes(cmd->bm, &unformatted); if (r) @@ -666,19 +685,85 @@ void dm_cache_metadata_close(struct dm_cache_metadata *cmd) kfree(cmd); } +/* + * Checks that the given cache block is either unmapped or clean. + */ +static int block_unmapped_or_clean(struct dm_cache_metadata *cmd, dm_cblock_t b, + bool *result) +{ + int r; + __le64 value; + dm_oblock_t ob; + unsigned flags; + + r = dm_array_get_value(&cmd->info, cmd->root, from_cblock(b), &value); + if (r) { + DMERR("block_unmapped_or_clean failed"); + return r; + } + + unpack_value(value, &ob, &flags); + *result = !((flags & M_VALID) && (flags & M_DIRTY)); + + return 0; +} + +static int blocks_are_unmapped_or_clean(struct dm_cache_metadata *cmd, + dm_cblock_t begin, dm_cblock_t end, + bool *result) +{ + int r; + *result = true; + + while (begin != end) { + r = block_unmapped_or_clean(cmd, begin, result); + if (r) + return r; + + if (!*result) { + DMERR("cache block %llu is dirty", + (unsigned long long) from_cblock(begin)); + return 0; + } + + begin = to_cblock(from_cblock(begin) + 1); + } + + return 0; +} + int dm_cache_resize(struct dm_cache_metadata *cmd, dm_cblock_t new_cache_size) { int r; + bool clean; __le64 null_mapping = pack_value(0, 0); down_write(&cmd->root_lock); __dm_bless_for_disk(&null_mapping); + + if (from_cblock(new_cache_size) < from_cblock(cmd->cache_blocks)) { + r = blocks_are_unmapped_or_clean(cmd, new_cache_size, cmd->cache_blocks, &clean); + if (r) { + __dm_unbless_for_disk(&null_mapping); + goto out; + } + + if (!clean) { + DMERR("unable to shrink cache due to dirty blocks"); + r = -EINVAL; + __dm_unbless_for_disk(&null_mapping); + goto out; + } + } + r = dm_array_resize(&cmd->info, cmd->root, from_cblock(cmd->cache_blocks), from_cblock(new_cache_size), &null_mapping, &cmd->root); if (!r) cmd->cache_blocks = new_cache_size; cmd->changed = true; + +out: up_write(&cmd->root_lock); return r; @@ -1182,3 +1267,8 @@ int dm_cache_save_hint(struct dm_cache_metadata *cmd, dm_cblock_t cblock, return r; } + +int dm_cache_metadata_all_clean(struct dm_cache_metadata *cmd, bool *result) +{ + return blocks_are_unmapped_or_clean(cmd, 0, cmd->cache_blocks, result); +} diff --git a/drivers/md/dm-cache-metadata.h b/drivers/md/dm-cache-metadata.h index f45cef2..cd906f1 100644 --- a/drivers/md/dm-cache-metadata.h +++ b/drivers/md/dm-cache-metadata.h @@ -137,6 +137,11 @@ int dm_cache_begin_hints(struct dm_cache_metadata *cmd, struct dm_cache_policy * int dm_cache_save_hint(struct dm_cache_metadata *cmd, dm_cblock_t cblock, uint32_t hint); +/* + * Query method. Are all the blocks in the cache clean? + */ +int dm_cache_metadata_all_clean(struct dm_cache_metadata *cmd, bool *result); + /*----------------------------------------------------------------*/ #endif /* DM_CACHE_METADATA_H */ diff --git a/drivers/md/dm-cache-policy-internal.h b/drivers/md/dm-cache-policy-internal.h index 0928abd..2256a1f 100644 --- a/drivers/md/dm-cache-policy-internal.h +++ b/drivers/md/dm-cache-policy-internal.h @@ -61,7 +61,12 @@ static inline int policy_writeback_work(struct dm_cache_policy *p, static inline void policy_remove_mapping(struct dm_cache_policy *p, dm_oblock_t oblock) { - return p->remove_mapping(p, oblock); + p->remove_mapping(p, oblock); +} + +static inline int policy_remove_cblock(struct dm_cache_policy *p, dm_cblock_t cblock) +{ + return p->remove_cblock(p, cblock); } static inline void policy_force_mapping(struct dm_cache_policy *p, diff --git a/drivers/md/dm-cache-policy-mq.c b/drivers/md/dm-cache-policy-mq.c index 4296155..416b7b7 100644 --- a/drivers/md/dm-cache-policy-mq.c +++ b/drivers/md/dm-cache-policy-mq.c @@ -26,19 +26,6 @@ static unsigned next_power(unsigned n, unsigned min) /*----------------------------------------------------------------*/ -static unsigned long *alloc_bitset(unsigned nr_entries) -{ - size_t s = sizeof(unsigned long) * dm_div_up(nr_entries, BITS_PER_LONG); - return vzalloc(s); -} - -static void free_bitset(unsigned long *bits) -{ - vfree(bits); -} - -/*----------------------------------------------------------------*/ - /* * Large, sequential ios are probably better left on the origin device since * spindles tend to have good bandwidth. @@ -151,6 +138,21 @@ static void queue_init(struct queue *q) } /* + * Checks to see if the queue is empty. + * FIXME: reduce cpu usage. + */ +static bool queue_empty(struct queue *q) +{ + unsigned i; + + for (i = 0; i < NR_QUEUE_LEVELS; i++) + if (!list_empty(q->qs + i)) + return false; + + return true; +} + +/* * Insert an entry to the back of the given level. */ static void queue_push(struct queue *q, unsigned level, struct list_head *elt) @@ -218,17 +220,116 @@ struct entry { struct hlist_node hlist; struct list_head list; dm_oblock_t oblock; - dm_cblock_t cblock; /* valid iff in_cache */ /* * FIXME: pack these better */ - bool in_cache:1; + bool dirty:1; unsigned hit_count; unsigned generation; unsigned tick; }; +/* + * Rather than storing the cblock in an entry, we allocate all entries in + * an array, and infer the cblock from the entry position. + * + * Free entries are linked together into a list. + */ +struct entry_pool { + struct entry *entries, *entries_end; + struct list_head free; + unsigned nr_allocated; +}; + +static int epool_init(struct entry_pool *ep, unsigned nr_entries) +{ + unsigned i; + + ep->entries = vzalloc(sizeof(struct entry) * nr_entries); + if (!ep->entries) + return -ENOMEM; + + ep->entries_end = ep->entries + nr_entries; + + INIT_LIST_HEAD(&ep->free); + for (i = 0; i < nr_entries; i++) + list_add(&ep->entries[i].list, &ep->free); + + ep->nr_allocated = 0; + + return 0; +} + +static void epool_exit(struct entry_pool *ep) +{ + vfree(ep->entries); +} + +static struct entry *alloc_entry(struct entry_pool *ep) +{ + struct entry *e; + + if (list_empty(&ep->free)) + return NULL; + + e = list_entry(list_pop(&ep->free), struct entry, list); + INIT_LIST_HEAD(&e->list); + INIT_HLIST_NODE(&e->hlist); + ep->nr_allocated++; + + return e; +} + +/* + * This assumes the cblock hasn't already been allocated. + */ +static struct entry *alloc_particular_entry(struct entry_pool *ep, dm_cblock_t cblock) +{ + struct entry *e = ep->entries + from_cblock(cblock); + list_del(&e->list); + + INIT_LIST_HEAD(&e->list); + INIT_HLIST_NODE(&e->hlist); + ep->nr_allocated++; + + return e; +} + +static void free_entry(struct entry_pool *ep, struct entry *e) +{ + BUG_ON(!ep->nr_allocated); + ep->nr_allocated--; + INIT_HLIST_NODE(&e->hlist); + list_add(&e->list, &ep->free); +} + +/* + * Returns NULL if the entry is free. + */ +static struct entry *epool_find(struct entry_pool *ep, dm_cblock_t cblock) +{ + struct entry *e = ep->entries + from_cblock(cblock); + return !hlist_unhashed(&e->hlist) ? e : NULL; +} + +static bool epool_empty(struct entry_pool *ep) +{ + return list_empty(&ep->free); +} + +static bool in_pool(struct entry_pool *ep, struct entry *e) +{ + return e >= ep->entries && e < ep->entries_end; +} + +static dm_cblock_t infer_cblock(struct entry_pool *ep, struct entry *e) +{ + return to_cblock(e - ep->entries); +} + +/*----------------------------------------------------------------*/ + struct mq_policy { struct dm_cache_policy policy; @@ -238,13 +339,22 @@ struct mq_policy { struct io_tracker tracker; /* - * We maintain two queues of entries. The cache proper contains - * the currently active mappings. Whereas the pre_cache tracks - * blocks that are being hit frequently and potential candidates - * for promotion to the cache. + * Entries come from two pools, one of pre-cache entries, and one + * for the cache proper. + */ + struct entry_pool pre_cache_pool; + struct entry_pool cache_pool; + + /* + * We maintain three queues of entries. The cache proper, + * consisting of a clean and dirty queue, contains the currently + * active mappings. Whereas the pre_cache tracks blocks that + * are being hit frequently and potential candidates for promotion + * to the cache. */ struct queue pre_cache; - struct queue cache; + struct queue cache_clean; + struct queue cache_dirty; /* * Keeps track of time, incremented by the core. We use this to @@ -282,25 +392,6 @@ struct mq_policy { unsigned promote_threshold; /* - * We need cache_size entries for the cache, and choose to have - * cache_size entries for the pre_cache too. One motivation for - * using the same size is to make the hit counts directly - * comparable between pre_cache and cache. - */ - unsigned nr_entries; - unsigned nr_entries_allocated; - struct list_head free; - - /* - * Cache blocks may be unallocated. We store this info in a - * bitset. - */ - unsigned long *allocation_bitset; - unsigned nr_cblocks_allocated; - unsigned find_free_nr_words; - unsigned find_free_last_word; - - /* * The hash table allows us to quickly find an entry by origin * block. Both pre_cache and cache entries are in here. */ @@ -310,49 +401,6 @@ struct mq_policy { }; /*----------------------------------------------------------------*/ -/* Free/alloc mq cache entry structures. */ -static void takeout_queue(struct list_head *lh, struct queue *q) -{ - unsigned level; - - for (level = 0; level < NR_QUEUE_LEVELS; level++) - list_splice(q->qs + level, lh); -} - -static void free_entries(struct mq_policy *mq) -{ - struct entry *e, *tmp; - - takeout_queue(&mq->free, &mq->pre_cache); - takeout_queue(&mq->free, &mq->cache); - - list_for_each_entry_safe(e, tmp, &mq->free, list) - kmem_cache_free(mq_entry_cache, e); -} - -static int alloc_entries(struct mq_policy *mq, unsigned elts) -{ - unsigned u = mq->nr_entries; - - INIT_LIST_HEAD(&mq->free); - mq->nr_entries_allocated = 0; - - while (u--) { - struct entry *e = kmem_cache_zalloc(mq_entry_cache, GFP_KERNEL); - - if (!e) { - free_entries(mq); - return -ENOMEM; - } - - - list_add(&e->list, &mq->free); - } - - return 0; -} - -/*----------------------------------------------------------------*/ /* * Simple hash table implementation. Should replace with the standard hash @@ -388,96 +436,14 @@ static void hash_remove(struct entry *e) /*----------------------------------------------------------------*/ -/* - * Allocates a new entry structure. The memory is allocated in one lump, - * so we just handing it out here. Returns NULL if all entries have - * already been allocated. Cannot fail otherwise. - */ -static struct entry *alloc_entry(struct mq_policy *mq) -{ - struct entry *e; - - if (mq->nr_entries_allocated >= mq->nr_entries) { - BUG_ON(!list_empty(&mq->free)); - return NULL; - } - - e = list_entry(list_pop(&mq->free), struct entry, list); - INIT_LIST_HEAD(&e->list); - INIT_HLIST_NODE(&e->hlist); - - mq->nr_entries_allocated++; - return e; -} - -/*----------------------------------------------------------------*/ - -/* - * Mark cache blocks allocated or not in the bitset. - */ -static void alloc_cblock(struct mq_policy *mq, dm_cblock_t cblock) -{ - BUG_ON(from_cblock(cblock) > from_cblock(mq->cache_size)); - BUG_ON(test_bit(from_cblock(cblock), mq->allocation_bitset)); - - set_bit(from_cblock(cblock), mq->allocation_bitset); - mq->nr_cblocks_allocated++; -} - -static void free_cblock(struct mq_policy *mq, dm_cblock_t cblock) -{ - BUG_ON(from_cblock(cblock) > from_cblock(mq->cache_size)); - BUG_ON(!test_bit(from_cblock(cblock), mq->allocation_bitset)); - - clear_bit(from_cblock(cblock), mq->allocation_bitset); - mq->nr_cblocks_allocated--; -} - static bool any_free_cblocks(struct mq_policy *mq) { - return mq->nr_cblocks_allocated < from_cblock(mq->cache_size); + return !epool_empty(&mq->cache_pool); } -/* - * Fills result out with a cache block that isn't in use, or return - * -ENOSPC. This does _not_ mark the cblock as allocated, the caller is - * reponsible for that. - */ -static int __find_free_cblock(struct mq_policy *mq, unsigned begin, unsigned end, - dm_cblock_t *result, unsigned *last_word) +static bool any_clean_cblocks(struct mq_policy *mq) { - int r = -ENOSPC; - unsigned w; - - for (w = begin; w < end; w++) { - /* - * ffz is undefined if no zero exists - */ - if (mq->allocation_bitset[w] != ~0UL) { - *last_word = w; - *result = to_cblock((w * BITS_PER_LONG) + ffz(mq->allocation_bitset[w])); - if (from_cblock(*result) < from_cblock(mq->cache_size)) - r = 0; - - break; - } - } - - return r; -} - -static int find_free_cblock(struct mq_policy *mq, dm_cblock_t *result) -{ - int r; - - if (!any_free_cblocks(mq)) - return -ENOSPC; - - r = __find_free_cblock(mq, mq->find_free_last_word, mq->find_free_nr_words, result, &mq->find_free_last_word); - if (r == -ENOSPC && mq->find_free_last_word) - r = __find_free_cblock(mq, 0, mq->find_free_last_word, result, &mq->find_free_last_word); - - return r; + return !queue_empty(&mq->cache_clean); } /*----------------------------------------------------------------*/ @@ -496,33 +462,35 @@ static unsigned queue_level(struct entry *e) return min((unsigned) ilog2(e->hit_count), NR_QUEUE_LEVELS - 1u); } +static bool in_cache(struct mq_policy *mq, struct entry *e) +{ + return in_pool(&mq->cache_pool, e); +} + /* * Inserts the entry into the pre_cache or the cache. Ensures the cache - * block is marked as allocated if necc. Inserts into the hash table. Sets the - * tick which records when the entry was last moved about. + * block is marked as allocated if necc. Inserts into the hash table. + * Sets the tick which records when the entry was last moved about. */ static void push(struct mq_policy *mq, struct entry *e) { e->tick = mq->tick; hash_insert(mq, e); - if (e->in_cache) { - alloc_cblock(mq, e->cblock); - queue_push(&mq->cache, queue_level(e), &e->list); - } else + if (in_cache(mq, e)) + queue_push(e->dirty ? &mq->cache_dirty : &mq->cache_clean, + queue_level(e), &e->list); + else queue_push(&mq->pre_cache, queue_level(e), &e->list); } /* * Removes an entry from pre_cache or cache. Removes from the hash table. - * Frees off the cache block if necc. */ static void del(struct mq_policy *mq, struct entry *e) { queue_remove(&e->list); hash_remove(e); - if (e->in_cache) - free_cblock(mq, e->cblock); } /* @@ -531,14 +499,14 @@ static void del(struct mq_policy *mq, struct entry *e) */ static struct entry *pop(struct mq_policy *mq, struct queue *q) { - struct entry *e = container_of(queue_pop(q), struct entry, list); + struct entry *e; + struct list_head *h = queue_pop(q); - if (e) { - hash_remove(e); + if (!h) + return NULL; - if (e->in_cache) - free_cblock(mq, e->cblock); - } + e = container_of(h, struct entry, list); + hash_remove(e); return e; } @@ -556,7 +524,8 @@ static bool updated_this_tick(struct mq_policy *mq, struct entry *e) * of the entries. * * At the moment the threshold is taken by averaging the hit counts of some - * of the entries in the cache (the first 20 entries of the first level). + * of the entries in the cache (the first 20 entries across all levels in + * ascending order, giving preference to the clean entries at each level). * * We can be much cleverer than this though. For example, each promotion * could bump up the threshold helping to prevent churn. Much more to do @@ -571,14 +540,21 @@ static void check_generation(struct mq_policy *mq) struct list_head *head; struct entry *e; - if ((mq->hit_count >= mq->generation_period) && - (mq->nr_cblocks_allocated == from_cblock(mq->cache_size))) { - + if ((mq->hit_count >= mq->generation_period) && (epool_empty(&mq->cache_pool))) { mq->hit_count = 0; mq->generation++; for (level = 0; level < NR_QUEUE_LEVELS && count < MAX_TO_AVERAGE; level++) { - head = mq->cache.qs + level; + head = mq->cache_clean.qs + level; + list_for_each_entry(e, head, list) { + nr++; + total += e->hit_count; + + if (++count >= MAX_TO_AVERAGE) + break; + } + + head = mq->cache_dirty.qs + level; list_for_each_entry(e, head, list) { nr++; total += e->hit_count; @@ -631,19 +607,30 @@ static void requeue_and_update_tick(struct mq_policy *mq, struct entry *e) * - set the hit count to a hard coded value other than 1, eg, is it better * if it goes in at level 2? */ -static dm_cblock_t demote_cblock(struct mq_policy *mq, dm_oblock_t *oblock) +static int demote_cblock(struct mq_policy *mq, dm_oblock_t *oblock) { - dm_cblock_t result; - struct entry *demoted = pop(mq, &mq->cache); + struct entry *demoted = pop(mq, &mq->cache_clean); + + if (!demoted) + /* + * We could get a block from mq->cache_dirty, but that + * would add extra latency to the triggering bio as it + * waits for the writeback. Better to not promote this + * time and hope there's a clean block next time this block + * is hit. + */ + return -ENOSPC; - BUG_ON(!demoted); - result = demoted->cblock; *oblock = demoted->oblock; - demoted->in_cache = false; - demoted->hit_count = 1; - push(mq, demoted); + free_entry(&mq->cache_pool, demoted); + + /* + * We used to put the demoted block into the pre-cache, but I think + * it's simpler to just let it work it's way up from zero again. + * Stops blocks flickering in and out of the cache. + */ - return result; + return 0; } /* @@ -662,17 +649,18 @@ static dm_cblock_t demote_cblock(struct mq_policy *mq, dm_oblock_t *oblock) static unsigned adjusted_promote_threshold(struct mq_policy *mq, bool discarded_oblock, int data_dir) { - if (discarded_oblock && any_free_cblocks(mq) && data_dir == WRITE) + if (data_dir == READ) + return mq->promote_threshold + READ_PROMOTE_THRESHOLD; + + if (discarded_oblock && (any_free_cblocks(mq) || any_clean_cblocks(mq))) { /* * We don't need to do any copying at all, so give this a - * very low threshold. In practice this only triggers - * during initial population after a format. + * very low threshold. */ return DISCARDED_PROMOTE_THRESHOLD; + } - return data_dir == READ ? - (mq->promote_threshold + READ_PROMOTE_THRESHOLD) : - (mq->promote_threshold + WRITE_PROMOTE_THRESHOLD); + return mq->promote_threshold + WRITE_PROMOTE_THRESHOLD; } static bool should_promote(struct mq_policy *mq, struct entry *e, @@ -688,34 +676,49 @@ static int cache_entry_found(struct mq_policy *mq, { requeue_and_update_tick(mq, e); - if (e->in_cache) { + if (in_cache(mq, e)) { result->op = POLICY_HIT; - result->cblock = e->cblock; + result->cblock = infer_cblock(&mq->cache_pool, e); } return 0; } /* - * Moves and entry from the pre_cache to the cache. The main work is + * Moves an entry from the pre_cache to the cache. The main work is * finding which cache block to use. */ static int pre_cache_to_cache(struct mq_policy *mq, struct entry *e, struct policy_result *result) { - dm_cblock_t cblock; + int r; + struct entry *new_e; - if (find_free_cblock(mq, &cblock) == -ENOSPC) { + /* Ensure there's a free cblock in the cache */ + if (epool_empty(&mq->cache_pool)) { result->op = POLICY_REPLACE; - cblock = demote_cblock(mq, &result->old_oblock); + r = demote_cblock(mq, &result->old_oblock); + if (r) { + result->op = POLICY_MISS; + return 0; + } } else result->op = POLICY_NEW; - result->cblock = e->cblock = cblock; + new_e = alloc_entry(&mq->cache_pool); + BUG_ON(!new_e); + + new_e->oblock = e->oblock; + new_e->dirty = false; + new_e->hit_count = e->hit_count; + new_e->generation = e->generation; + new_e->tick = e->tick; del(mq, e); - e->in_cache = true; - push(mq, e); + free_entry(&mq->pre_cache_pool, e); + push(mq, new_e); + + result->cblock = infer_cblock(&mq->cache_pool, new_e); return 0; } @@ -743,7 +746,7 @@ static int pre_cache_entry_found(struct mq_policy *mq, struct entry *e, static void insert_in_pre_cache(struct mq_policy *mq, dm_oblock_t oblock) { - struct entry *e = alloc_entry(mq); + struct entry *e = alloc_entry(&mq->pre_cache_pool); if (!e) /* @@ -757,7 +760,7 @@ static void insert_in_pre_cache(struct mq_policy *mq, return; } - e->in_cache = false; + e->dirty = false; e->oblock = oblock; e->hit_count = 1; e->generation = mq->generation; @@ -767,30 +770,36 @@ static void insert_in_pre_cache(struct mq_policy *mq, static void insert_in_cache(struct mq_policy *mq, dm_oblock_t oblock, struct policy_result *result) { + int r; struct entry *e; - dm_cblock_t cblock; - if (find_free_cblock(mq, &cblock) == -ENOSPC) { - result->op = POLICY_MISS; - insert_in_pre_cache(mq, oblock); - return; - } + if (epool_empty(&mq->cache_pool)) { + result->op = POLICY_REPLACE; + r = demote_cblock(mq, &result->old_oblock); + if (unlikely(r)) { + result->op = POLICY_MISS; + insert_in_pre_cache(mq, oblock); + return; + } - e = alloc_entry(mq); - if (unlikely(!e)) { - result->op = POLICY_MISS; - return; + /* + * This will always succeed, since we've just demoted. + */ + e = alloc_entry(&mq->cache_pool); + BUG_ON(!e); + + } else { + e = alloc_entry(&mq->cache_pool); + result->op = POLICY_NEW; } e->oblock = oblock; - e->cblock = cblock; - e->in_cache = true; + e->dirty = false; e->hit_count = 1; e->generation = mq->generation; push(mq, e); - result->op = POLICY_NEW; - result->cblock = e->cblock; + result->cblock = infer_cblock(&mq->cache_pool, e); } static int no_entry_found(struct mq_policy *mq, dm_oblock_t oblock, @@ -821,13 +830,16 @@ static int map(struct mq_policy *mq, dm_oblock_t oblock, int r = 0; struct entry *e = hash_lookup(mq, oblock); - if (e && e->in_cache) + if (e && in_cache(mq, e)) r = cache_entry_found(mq, e, result); + else if (iot_pattern(&mq->tracker) == PATTERN_SEQUENTIAL) result->op = POLICY_MISS; + else if (e) r = pre_cache_entry_found(mq, e, can_migrate, discarded_oblock, data_dir, result); + else r = no_entry_found(mq, oblock, can_migrate, discarded_oblock, data_dir, result); @@ -854,9 +866,9 @@ static void mq_destroy(struct dm_cache_policy *p) { struct mq_policy *mq = to_mq_policy(p); - free_bitset(mq->allocation_bitset); kfree(mq->table); - free_entries(mq); + epool_exit(&mq->cache_pool); + epool_exit(&mq->pre_cache_pool); kfree(mq); } @@ -904,8 +916,8 @@ static int mq_lookup(struct dm_cache_policy *p, dm_oblock_t oblock, dm_cblock_t return -EWOULDBLOCK; e = hash_lookup(mq, oblock); - if (e && e->in_cache) { - *cblock = e->cblock; + if (e && in_cache(mq, e)) { + *cblock = infer_cblock(&mq->cache_pool, e); r = 0; } else r = -ENOENT; @@ -915,6 +927,36 @@ static int mq_lookup(struct dm_cache_policy *p, dm_oblock_t oblock, dm_cblock_t return r; } +static void __mq_set_clear_dirty(struct mq_policy *mq, dm_oblock_t oblock, bool set) +{ + struct entry *e; + + e = hash_lookup(mq, oblock); + BUG_ON(!e || !in_cache(mq, e)); + + del(mq, e); + e->dirty = set; + push(mq, e); +} + +static void mq_set_dirty(struct dm_cache_policy *p, dm_oblock_t oblock) +{ + struct mq_policy *mq = to_mq_policy(p); + + mutex_lock(&mq->lock); + __mq_set_clear_dirty(mq, oblock, true); + mutex_unlock(&mq->lock); +} + +static void mq_clear_dirty(struct dm_cache_policy *p, dm_oblock_t oblock) +{ + struct mq_policy *mq = to_mq_policy(p); + + mutex_lock(&mq->lock); + __mq_set_clear_dirty(mq, oblock, false); + mutex_unlock(&mq->lock); +} + static int mq_load_mapping(struct dm_cache_policy *p, dm_oblock_t oblock, dm_cblock_t cblock, uint32_t hint, bool hint_valid) @@ -922,13 +964,9 @@ static int mq_load_mapping(struct dm_cache_policy *p, struct mq_policy *mq = to_mq_policy(p); struct entry *e; - e = alloc_entry(mq); - if (!e) - return -ENOMEM; - - e->cblock = cblock; + e = alloc_particular_entry(&mq->cache_pool, cblock); e->oblock = oblock; - e->in_cache = true; + e->dirty = false; /* this gets corrected in a minute */ e->hit_count = hint_valid ? hint : 1; e->generation = mq->generation; push(mq, e); @@ -936,57 +974,126 @@ static int mq_load_mapping(struct dm_cache_policy *p, return 0; } +static int mq_save_hints(struct mq_policy *mq, struct queue *q, + policy_walk_fn fn, void *context) +{ + int r; + unsigned level; + struct entry *e; + + for (level = 0; level < NR_QUEUE_LEVELS; level++) + list_for_each_entry(e, q->qs + level, list) { + r = fn(context, infer_cblock(&mq->cache_pool, e), + e->oblock, e->hit_count); + if (r) + return r; + } + + return 0; +} + static int mq_walk_mappings(struct dm_cache_policy *p, policy_walk_fn fn, void *context) { struct mq_policy *mq = to_mq_policy(p); int r = 0; - struct entry *e; - unsigned level; mutex_lock(&mq->lock); - for (level = 0; level < NR_QUEUE_LEVELS; level++) - list_for_each_entry(e, &mq->cache.qs[level], list) { - r = fn(context, e->cblock, e->oblock, e->hit_count); - if (r) - goto out; - } + r = mq_save_hints(mq, &mq->cache_clean, fn, context); + if (!r) + r = mq_save_hints(mq, &mq->cache_dirty, fn, context); -out: mutex_unlock(&mq->lock); return r; } +static void __remove_mapping(struct mq_policy *mq, dm_oblock_t oblock) +{ + struct entry *e; + + e = hash_lookup(mq, oblock); + BUG_ON(!e || !in_cache(mq, e)); + + del(mq, e); + free_entry(&mq->cache_pool, e); +} + static void mq_remove_mapping(struct dm_cache_policy *p, dm_oblock_t oblock) { struct mq_policy *mq = to_mq_policy(p); - struct entry *e; mutex_lock(&mq->lock); + __remove_mapping(mq, oblock); + mutex_unlock(&mq->lock); +} - e = hash_lookup(mq, oblock); +static int __remove_cblock(struct mq_policy *mq, dm_cblock_t cblock) +{ + struct entry *e = epool_find(&mq->cache_pool, cblock); - BUG_ON(!e || !e->in_cache); + if (!e) + return -ENODATA; del(mq, e); - e->in_cache = false; - push(mq, e); + free_entry(&mq->cache_pool, e); + return 0; +} + +static int mq_remove_cblock(struct dm_cache_policy *p, dm_cblock_t cblock) +{ + int r; + struct mq_policy *mq = to_mq_policy(p); + + mutex_lock(&mq->lock); + r = __remove_cblock(mq, cblock); mutex_unlock(&mq->lock); + + return r; } -static void force_mapping(struct mq_policy *mq, - dm_oblock_t current_oblock, dm_oblock_t new_oblock) +static int __mq_writeback_work(struct mq_policy *mq, dm_oblock_t *oblock, + dm_cblock_t *cblock) { - struct entry *e = hash_lookup(mq, current_oblock); + struct entry *e = pop(mq, &mq->cache_dirty); - BUG_ON(!e || !e->in_cache); + if (!e) + return -ENODATA; - del(mq, e); - e->oblock = new_oblock; + *oblock = e->oblock; + *cblock = infer_cblock(&mq->cache_pool, e); + e->dirty = false; push(mq, e); + + return 0; +} + +static int mq_writeback_work(struct dm_cache_policy *p, dm_oblock_t *oblock, + dm_cblock_t *cblock) +{ + int r; + struct mq_policy *mq = to_mq_policy(p); + + mutex_lock(&mq->lock); + r = __mq_writeback_work(mq, oblock, cblock); + mutex_unlock(&mq->lock); + + return r; +} + +static void __force_mapping(struct mq_policy *mq, + dm_oblock_t current_oblock, dm_oblock_t new_oblock) +{ + struct entry *e = hash_lookup(mq, current_oblock); + + if (e && in_cache(mq, e)) { + del(mq, e); + e->oblock = new_oblock; + e->dirty = true; + push(mq, e); + } } static void mq_force_mapping(struct dm_cache_policy *p, @@ -995,16 +1102,20 @@ static void mq_force_mapping(struct dm_cache_policy *p, struct mq_policy *mq = to_mq_policy(p); mutex_lock(&mq->lock); - force_mapping(mq, current_oblock, new_oblock); + __force_mapping(mq, current_oblock, new_oblock); mutex_unlock(&mq->lock); } static dm_cblock_t mq_residency(struct dm_cache_policy *p) { + dm_cblock_t r; struct mq_policy *mq = to_mq_policy(p); - /* FIXME: lock mutex, not sure we can block here */ - return to_cblock(mq->nr_cblocks_allocated); + mutex_lock(&mq->lock); + r = to_cblock(mq->cache_pool.nr_allocated); + mutex_unlock(&mq->lock); + + return r; } static void mq_tick(struct dm_cache_policy *p) @@ -1057,10 +1168,13 @@ static void init_policy_functions(struct mq_policy *mq) mq->policy.destroy = mq_destroy; mq->policy.map = mq_map; mq->policy.lookup = mq_lookup; + mq->policy.set_dirty = mq_set_dirty; + mq->policy.clear_dirty = mq_clear_dirty; mq->policy.load_mapping = mq_load_mapping; mq->policy.walk_mappings = mq_walk_mappings; mq->policy.remove_mapping = mq_remove_mapping; - mq->policy.writeback_work = NULL; + mq->policy.remove_cblock = mq_remove_cblock; + mq->policy.writeback_work = mq_writeback_work; mq->policy.force_mapping = mq_force_mapping; mq->policy.residency = mq_residency; mq->policy.tick = mq_tick; @@ -1072,7 +1186,6 @@ static struct dm_cache_policy *mq_create(dm_cblock_t cache_size, sector_t origin_size, sector_t cache_block_size) { - int r; struct mq_policy *mq = kzalloc(sizeof(*mq), GFP_KERNEL); if (!mq) @@ -1080,8 +1193,18 @@ static struct dm_cache_policy *mq_create(dm_cblock_t cache_size, init_policy_functions(mq); iot_init(&mq->tracker, SEQUENTIAL_THRESHOLD_DEFAULT, RANDOM_THRESHOLD_DEFAULT); - mq->cache_size = cache_size; + + if (epool_init(&mq->pre_cache_pool, from_cblock(cache_size))) { + DMERR("couldn't initialize pool of pre-cache entries"); + goto bad_pre_cache_init; + } + + if (epool_init(&mq->cache_pool, from_cblock(cache_size))) { + DMERR("couldn't initialize pool of cache entries"); + goto bad_cache_init; + } + mq->tick_protected = 0; mq->tick = 0; mq->hit_count = 0; @@ -1089,20 +1212,12 @@ static struct dm_cache_policy *mq_create(dm_cblock_t cache_size, mq->promote_threshold = 0; mutex_init(&mq->lock); spin_lock_init(&mq->tick_lock); - mq->find_free_nr_words = dm_div_up(from_cblock(mq->cache_size), BITS_PER_LONG); - mq->find_free_last_word = 0; queue_init(&mq->pre_cache); - queue_init(&mq->cache); - mq->generation_period = max((unsigned) from_cblock(cache_size), 1024U); + queue_init(&mq->cache_clean); + queue_init(&mq->cache_dirty); - mq->nr_entries = 2 * from_cblock(cache_size); - r = alloc_entries(mq, mq->nr_entries); - if (r) - goto bad_cache_alloc; - - mq->nr_entries_allocated = 0; - mq->nr_cblocks_allocated = 0; + mq->generation_period = max((unsigned) from_cblock(cache_size), 1024U); mq->nr_buckets = next_power(from_cblock(cache_size) / 2, 16); mq->hash_bits = ffs(mq->nr_buckets) - 1; @@ -1110,17 +1225,13 @@ static struct dm_cache_policy *mq_create(dm_cblock_t cache_size, if (!mq->table) goto bad_alloc_table; - mq->allocation_bitset = alloc_bitset(from_cblock(cache_size)); - if (!mq->allocation_bitset) - goto bad_alloc_bitset; - return &mq->policy; -bad_alloc_bitset: - kfree(mq->table); bad_alloc_table: - free_entries(mq); -bad_cache_alloc: + epool_exit(&mq->cache_pool); +bad_cache_init: + epool_exit(&mq->pre_cache_pool); +bad_pre_cache_init: kfree(mq); return NULL; @@ -1130,7 +1241,7 @@ bad_cache_alloc: static struct dm_cache_policy_type mq_policy_type = { .name = "mq", - .version = {1, 0, 0}, + .version = {1, 1, 0}, .hint_size = 4, .owner = THIS_MODULE, .create = mq_create @@ -1138,7 +1249,7 @@ static struct dm_cache_policy_type mq_policy_type = { static struct dm_cache_policy_type default_policy_type = { .name = "default", - .version = {1, 0, 0}, + .version = {1, 1, 0}, .hint_size = 4, .owner = THIS_MODULE, .create = mq_create diff --git a/drivers/md/dm-cache-policy.c b/drivers/md/dm-cache-policy.c index 21c03c5..d800579 100644 --- a/drivers/md/dm-cache-policy.c +++ b/drivers/md/dm-cache-policy.c @@ -119,13 +119,13 @@ struct dm_cache_policy *dm_cache_policy_create(const char *name, type = get_policy(name); if (!type) { DMWARN("unknown policy type"); - return NULL; + return ERR_PTR(-EINVAL); } p = type->create(cache_size, origin_size, cache_block_size); if (!p) { put_policy(type); - return NULL; + return ERR_PTR(-ENOMEM); } p->private = type; diff --git a/drivers/md/dm-cache-policy.h b/drivers/md/dm-cache-policy.h index 33369ca..052c00a 100644 --- a/drivers/md/dm-cache-policy.h +++ b/drivers/md/dm-cache-policy.h @@ -135,9 +135,6 @@ struct dm_cache_policy { */ int (*lookup)(struct dm_cache_policy *p, dm_oblock_t oblock, dm_cblock_t *cblock); - /* - * oblock must be a mapped block. Must not block. - */ void (*set_dirty)(struct dm_cache_policy *p, dm_oblock_t oblock); void (*clear_dirty)(struct dm_cache_policy *p, dm_oblock_t oblock); @@ -159,8 +156,24 @@ struct dm_cache_policy { void (*force_mapping)(struct dm_cache_policy *p, dm_oblock_t current_oblock, dm_oblock_t new_oblock); - int (*writeback_work)(struct dm_cache_policy *p, dm_oblock_t *oblock, dm_cblock_t *cblock); + /* + * This is called via the invalidate_cblocks message. It is + * possible the particular cblock has already been removed due to a + * write io in passthrough mode. In which case this should return + * -ENODATA. + */ + int (*remove_cblock)(struct dm_cache_policy *p, dm_cblock_t cblock); + /* + * Provide a dirty block to be written back by the core target. + * + * Returns: + * + * 0 and @cblock,@oblock: block to write back provided + * + * -ENODATA: no dirty blocks available + */ + int (*writeback_work)(struct dm_cache_policy *p, dm_oblock_t *oblock, dm_cblock_t *cblock); /* * How full is the cache? diff --git a/drivers/md/dm-cache-target.c b/drivers/md/dm-cache-target.c index 2956976..9efcf10 100644 --- a/drivers/md/dm-cache-target.c +++ b/drivers/md/dm-cache-target.c @@ -61,6 +61,34 @@ static void free_bitset(unsigned long *bits) /*----------------------------------------------------------------*/ +/* + * There are a couple of places where we let a bio run, but want to do some + * work before calling its endio function. We do this by temporarily + * changing the endio fn. + */ +struct dm_hook_info { + bio_end_io_t *bi_end_io; + void *bi_private; +}; + +static void dm_hook_bio(struct dm_hook_info *h, struct bio *bio, + bio_end_io_t *bi_end_io, void *bi_private) +{ + h->bi_end_io = bio->bi_end_io; + h->bi_private = bio->bi_private; + + bio->bi_end_io = bi_end_io; + bio->bi_private = bi_private; +} + +static void dm_unhook_bio(struct dm_hook_info *h, struct bio *bio) +{ + bio->bi_end_io = h->bi_end_io; + bio->bi_private = h->bi_private; +} + +/*----------------------------------------------------------------*/ + #define PRISON_CELLS 1024 #define MIGRATION_POOL_SIZE 128 #define COMMIT_PERIOD HZ @@ -76,14 +104,37 @@ static void free_bitset(unsigned long *bits) /* * FIXME: the cache is read/write for the time being. */ -enum cache_mode { +enum cache_metadata_mode { CM_WRITE, /* metadata may be changed */ CM_READ_ONLY, /* metadata may not be changed */ }; +enum cache_io_mode { + /* + * Data is written to cached blocks only. These blocks are marked + * dirty. If you lose the cache device you will lose data. + * Potential performance increase for both reads and writes. + */ + CM_IO_WRITEBACK, + + /* + * Data is written to both cache and origin. Blocks are never + * dirty. Potential performance benfit for reads only. + */ + CM_IO_WRITETHROUGH, + + /* + * A degraded mode useful for various cache coherency situations + * (eg, rolling back snapshots). Reads and writes always go to the + * origin. If a write goes to a cached oblock, then the cache + * block is invalidated. + */ + CM_IO_PASSTHROUGH +}; + struct cache_features { - enum cache_mode mode; - bool write_through:1; + enum cache_metadata_mode mode; + enum cache_io_mode io_mode; }; struct cache_stats { @@ -99,6 +150,25 @@ struct cache_stats { atomic_t discard_count; }; +/* + * Defines a range of cblocks, begin to (end - 1) are in the range. end is + * the one-past-the-end value. + */ +struct cblock_range { + dm_cblock_t begin; + dm_cblock_t end; +}; + +struct invalidation_request { + struct list_head list; + struct cblock_range *cblocks; + + atomic_t complete; + int err; + + wait_queue_head_t result_wait; +}; + struct cache { struct dm_target *ti; struct dm_target_callbacks callbacks; @@ -148,6 +218,10 @@ struct cache { wait_queue_head_t migration_wait; atomic_t nr_migrations; + wait_queue_head_t quiescing_wait; + atomic_t quiescing; + atomic_t quiescing_ack; + /* * cache_size entries, dirty if set */ @@ -186,7 +260,7 @@ struct cache { bool need_tick_bio:1; bool sized:1; - bool quiescing:1; + bool invalidate:1; bool commit_requested:1; bool loaded_mappings:1; bool loaded_discards:1; @@ -197,6 +271,12 @@ struct cache { struct cache_features features; struct cache_stats stats; + + /* + * Invalidation fields. + */ + spinlock_t invalidation_lock; + struct list_head invalidation_requests; }; struct per_bio_data { @@ -211,7 +291,7 @@ struct per_bio_data { */ struct cache *cache; dm_cblock_t cblock; - bio_end_io_t *saved_bi_end_io; + struct dm_hook_info hook_info; struct dm_bio_details bio_details; }; @@ -228,6 +308,8 @@ struct dm_cache_migration { bool writeback:1; bool demote:1; bool promote:1; + bool requeue_holder:1; + bool invalidate:1; struct dm_bio_prison_cell *old_ocell; struct dm_bio_prison_cell *new_ocell; @@ -533,9 +615,24 @@ static void save_stats(struct cache *cache) #define PB_DATA_SIZE_WB (offsetof(struct per_bio_data, cache)) #define PB_DATA_SIZE_WT (sizeof(struct per_bio_data)) +static bool writethrough_mode(struct cache_features *f) +{ + return f->io_mode == CM_IO_WRITETHROUGH; +} + +static bool writeback_mode(struct cache_features *f) +{ + return f->io_mode == CM_IO_WRITEBACK; +} + +static bool passthrough_mode(struct cache_features *f) +{ + return f->io_mode == CM_IO_PASSTHROUGH; +} + static size_t get_per_bio_data_size(struct cache *cache) { - return cache->features.write_through ? PB_DATA_SIZE_WT : PB_DATA_SIZE_WB; + return writethrough_mode(&cache->features) ? PB_DATA_SIZE_WT : PB_DATA_SIZE_WB; } static struct per_bio_data *get_per_bio_data(struct bio *bio, size_t data_size) @@ -605,6 +702,7 @@ static void remap_to_origin_clear_discard(struct cache *cache, struct bio *bio, static void remap_to_cache_dirty(struct cache *cache, struct bio *bio, dm_oblock_t oblock, dm_cblock_t cblock) { + check_if_tick_bio_needed(cache, bio); remap_to_cache(cache, bio, cblock); if (bio_data_dir(bio) == WRITE) { set_dirty(cache, oblock, cblock); @@ -662,7 +760,8 @@ static void defer_writethrough_bio(struct cache *cache, struct bio *bio) static void writethrough_endio(struct bio *bio, int err) { struct per_bio_data *pb = get_per_bio_data(bio, PB_DATA_SIZE_WT); - bio->bi_end_io = pb->saved_bi_end_io; + + dm_unhook_bio(&pb->hook_info, bio); if (err) { bio_endio(bio, err); @@ -693,9 +792,8 @@ static void remap_to_origin_then_cache(struct cache *cache, struct bio *bio, pb->cache = cache; pb->cblock = cblock; - pb->saved_bi_end_io = bio->bi_end_io; + dm_hook_bio(&pb->hook_info, bio, writethrough_endio, NULL); dm_bio_record(&pb->bio_details, bio); - bio->bi_end_io = writethrough_endio; remap_to_origin_clear_discard(pb->cache, bio, oblock); } @@ -748,8 +846,9 @@ static void cell_defer(struct cache *cache, struct dm_bio_prison_cell *cell, static void cleanup_migration(struct dm_cache_migration *mg) { - dec_nr_migrations(mg->cache); + struct cache *cache = mg->cache; free_migration(mg); + dec_nr_migrations(cache); } static void migration_failure(struct dm_cache_migration *mg) @@ -765,13 +864,13 @@ static void migration_failure(struct dm_cache_migration *mg) DMWARN_LIMIT("demotion failed; couldn't copy block"); policy_force_mapping(cache->policy, mg->new_oblock, mg->old_oblock); - cell_defer(cache, mg->old_ocell, mg->promote ? 0 : 1); + cell_defer(cache, mg->old_ocell, mg->promote ? false : true); if (mg->promote) - cell_defer(cache, mg->new_ocell, 1); + cell_defer(cache, mg->new_ocell, true); } else { DMWARN_LIMIT("promotion failed; couldn't copy block"); policy_remove_mapping(cache->policy, mg->new_oblock); - cell_defer(cache, mg->new_ocell, 1); + cell_defer(cache, mg->new_ocell, true); } cleanup_migration(mg); @@ -823,7 +922,7 @@ static void migration_success_post_commit(struct dm_cache_migration *mg) return; } else if (mg->demote) { - cell_defer(cache, mg->old_ocell, mg->promote ? 0 : 1); + cell_defer(cache, mg->old_ocell, mg->promote ? false : true); if (mg->promote) { mg->demote = false; @@ -832,11 +931,19 @@ static void migration_success_post_commit(struct dm_cache_migration *mg) list_add_tail(&mg->list, &cache->quiesced_migrations); spin_unlock_irqrestore(&cache->lock, flags); - } else + } else { + if (mg->invalidate) + policy_remove_mapping(cache->policy, mg->old_oblock); cleanup_migration(mg); + } } else { - cell_defer(cache, mg->new_ocell, true); + if (mg->requeue_holder) + cell_defer(cache, mg->new_ocell, true); + else { + bio_endio(mg->new_ocell->holder, 0); + cell_defer(cache, mg->new_ocell, false); + } clear_dirty(cache, mg->new_oblock, mg->cblock); cleanup_migration(mg); } @@ -881,8 +988,46 @@ static void issue_copy_real(struct dm_cache_migration *mg) r = dm_kcopyd_copy(cache->copier, &o_region, 1, &c_region, 0, copy_complete, mg); } - if (r < 0) + if (r < 0) { + DMERR_LIMIT("issuing migration failed"); migration_failure(mg); + } +} + +static void overwrite_endio(struct bio *bio, int err) +{ + struct dm_cache_migration *mg = bio->bi_private; + struct cache *cache = mg->cache; + size_t pb_data_size = get_per_bio_data_size(cache); + struct per_bio_data *pb = get_per_bio_data(bio, pb_data_size); + unsigned long flags; + + if (err) + mg->err = true; + + spin_lock_irqsave(&cache->lock, flags); + list_add_tail(&mg->list, &cache->completed_migrations); + dm_unhook_bio(&pb->hook_info, bio); + mg->requeue_holder = false; + spin_unlock_irqrestore(&cache->lock, flags); + + wake_worker(cache); +} + +static void issue_overwrite(struct dm_cache_migration *mg, struct bio *bio) +{ + size_t pb_data_size = get_per_bio_data_size(mg->cache); + struct per_bio_data *pb = get_per_bio_data(bio, pb_data_size); + + dm_hook_bio(&pb->hook_info, bio, overwrite_endio, mg); + remap_to_cache_dirty(mg->cache, bio, mg->new_oblock, mg->cblock); + generic_make_request(bio); +} + +static bool bio_writes_complete_block(struct cache *cache, struct bio *bio) +{ + return (bio_data_dir(bio) == WRITE) && + (bio->bi_size == (cache->sectors_per_block << SECTOR_SHIFT)); } static void avoid_copy(struct dm_cache_migration *mg) @@ -899,9 +1044,17 @@ static void issue_copy(struct dm_cache_migration *mg) if (mg->writeback || mg->demote) avoid = !is_dirty(cache, mg->cblock) || is_discarded_oblock(cache, mg->old_oblock); - else + else { + struct bio *bio = mg->new_ocell->holder; + avoid = is_discarded_oblock(cache, mg->new_oblock); + if (!avoid && bio_writes_complete_block(cache, bio)) { + issue_overwrite(mg, bio); + return; + } + } + avoid ? avoid_copy(mg) : issue_copy_real(mg); } @@ -991,6 +1144,8 @@ static void promote(struct cache *cache, struct prealloc *structs, mg->writeback = false; mg->demote = false; mg->promote = true; + mg->requeue_holder = true; + mg->invalidate = false; mg->cache = cache; mg->new_oblock = oblock; mg->cblock = cblock; @@ -1012,6 +1167,8 @@ static void writeback(struct cache *cache, struct prealloc *structs, mg->writeback = true; mg->demote = false; mg->promote = false; + mg->requeue_holder = true; + mg->invalidate = false; mg->cache = cache; mg->old_oblock = oblock; mg->cblock = cblock; @@ -1035,6 +1192,8 @@ static void demote_then_promote(struct cache *cache, struct prealloc *structs, mg->writeback = false; mg->demote = true; mg->promote = true; + mg->requeue_holder = true; + mg->invalidate = false; mg->cache = cache; mg->old_oblock = old_oblock; mg->new_oblock = new_oblock; @@ -1047,6 +1206,33 @@ static void demote_then_promote(struct cache *cache, struct prealloc *structs, quiesce_migration(mg); } +/* + * Invalidate a cache entry. No writeback occurs; any changes in the cache + * block are thrown away. + */ +static void invalidate(struct cache *cache, struct prealloc *structs, + dm_oblock_t oblock, dm_cblock_t cblock, + struct dm_bio_prison_cell *cell) +{ + struct dm_cache_migration *mg = prealloc_get_migration(structs); + + mg->err = false; + mg->writeback = false; + mg->demote = true; + mg->promote = false; + mg->requeue_holder = true; + mg->invalidate = true; + mg->cache = cache; + mg->old_oblock = oblock; + mg->cblock = cblock; + mg->old_ocell = cell; + mg->new_ocell = NULL; + mg->start_jiffies = jiffies; + + inc_nr_migrations(cache); + quiesce_migration(mg); +} + /*---------------------------------------------------------------- * bio processing *--------------------------------------------------------------*/ @@ -1109,13 +1295,6 @@ static bool spare_migration_bandwidth(struct cache *cache) return current_volume < cache->migration_threshold; } -static bool is_writethrough_io(struct cache *cache, struct bio *bio, - dm_cblock_t cblock) -{ - return bio_data_dir(bio) == WRITE && - cache->features.write_through && !is_dirty(cache, cblock); -} - static void inc_hit_counter(struct cache *cache, struct bio *bio) { atomic_inc(bio_data_dir(bio) == READ ? @@ -1128,6 +1307,15 @@ static void inc_miss_counter(struct cache *cache, struct bio *bio) &cache->stats.read_miss : &cache->stats.write_miss); } +static void issue_cache_bio(struct cache *cache, struct bio *bio, + struct per_bio_data *pb, + dm_oblock_t oblock, dm_cblock_t cblock) +{ + pb->all_io_entry = dm_deferred_entry_inc(cache->all_io_ds); + remap_to_cache_dirty(cache, bio, oblock, cblock); + issue(cache, bio); +} + static void process_bio(struct cache *cache, struct prealloc *structs, struct bio *bio) { @@ -1139,7 +1327,8 @@ static void process_bio(struct cache *cache, struct prealloc *structs, size_t pb_data_size = get_per_bio_data_size(cache); struct per_bio_data *pb = get_per_bio_data(bio, pb_data_size); bool discarded_block = is_discarded_oblock(cache, block); - bool can_migrate = discarded_block || spare_migration_bandwidth(cache); + bool passthrough = passthrough_mode(&cache->features); + bool can_migrate = !passthrough && (discarded_block || spare_migration_bandwidth(cache)); /* * Check to see if that block is currently migrating. @@ -1160,15 +1349,39 @@ static void process_bio(struct cache *cache, struct prealloc *structs, switch (lookup_result.op) { case POLICY_HIT: - inc_hit_counter(cache, bio); - pb->all_io_entry = dm_deferred_entry_inc(cache->all_io_ds); + if (passthrough) { + inc_miss_counter(cache, bio); - if (is_writethrough_io(cache, bio, lookup_result.cblock)) - remap_to_origin_then_cache(cache, bio, block, lookup_result.cblock); - else - remap_to_cache_dirty(cache, bio, block, lookup_result.cblock); + /* + * Passthrough always maps to the origin, + * invalidating any cache blocks that are written + * to. + */ + + if (bio_data_dir(bio) == WRITE) { + atomic_inc(&cache->stats.demotion); + invalidate(cache, structs, block, lookup_result.cblock, new_ocell); + release_cell = false; + + } else { + /* FIXME: factor out issue_origin() */ + pb->all_io_entry = dm_deferred_entry_inc(cache->all_io_ds); + remap_to_origin_clear_discard(cache, bio, block); + issue(cache, bio); + } + } else { + inc_hit_counter(cache, bio); + + if (bio_data_dir(bio) == WRITE && + writethrough_mode(&cache->features) && + !is_dirty(cache, lookup_result.cblock)) { + pb->all_io_entry = dm_deferred_entry_inc(cache->all_io_ds); + remap_to_origin_then_cache(cache, bio, block, lookup_result.cblock); + issue(cache, bio); + } else + issue_cache_bio(cache, bio, pb, block, lookup_result.cblock); + } - issue(cache, bio); break; case POLICY_MISS: @@ -1227,15 +1440,17 @@ static int need_commit_due_to_time(struct cache *cache) static int commit_if_needed(struct cache *cache) { - if (dm_cache_changed_this_transaction(cache->cmd) && - (cache->commit_requested || need_commit_due_to_time(cache))) { + int r = 0; + + if ((cache->commit_requested || need_commit_due_to_time(cache)) && + dm_cache_changed_this_transaction(cache->cmd)) { atomic_inc(&cache->stats.commit_count); - cache->last_commit_jiffies = jiffies; cache->commit_requested = false; - return dm_cache_commit(cache->cmd, false); + r = dm_cache_commit(cache->cmd, false); + cache->last_commit_jiffies = jiffies; } - return 0; + return r; } static void process_deferred_bios(struct cache *cache) @@ -1344,36 +1559,88 @@ static void writeback_some_dirty_blocks(struct cache *cache) } /*---------------------------------------------------------------- - * Main worker loop + * Invalidations. + * Dropping something from the cache *without* writing back. *--------------------------------------------------------------*/ -static void start_quiescing(struct cache *cache) + +static void process_invalidation_request(struct cache *cache, struct invalidation_request *req) { - unsigned long flags; + int r = 0; + uint64_t begin = from_cblock(req->cblocks->begin); + uint64_t end = from_cblock(req->cblocks->end); - spin_lock_irqsave(&cache->lock, flags); - cache->quiescing = 1; - spin_unlock_irqrestore(&cache->lock, flags); + while (begin != end) { + r = policy_remove_cblock(cache->policy, to_cblock(begin)); + if (!r) { + r = dm_cache_remove_mapping(cache->cmd, to_cblock(begin)); + if (r) + break; + + } else if (r == -ENODATA) { + /* harmless, already unmapped */ + r = 0; + + } else { + DMERR("policy_remove_cblock failed"); + break; + } + + begin++; + } + + cache->commit_requested = true; + + req->err = r; + atomic_set(&req->complete, 1); + + wake_up(&req->result_wait); } -static void stop_quiescing(struct cache *cache) +static void process_invalidation_requests(struct cache *cache) { - unsigned long flags; + struct list_head list; + struct invalidation_request *req, *tmp; - spin_lock_irqsave(&cache->lock, flags); - cache->quiescing = 0; - spin_unlock_irqrestore(&cache->lock, flags); + INIT_LIST_HEAD(&list); + spin_lock(&cache->invalidation_lock); + list_splice_init(&cache->invalidation_requests, &list); + spin_unlock(&cache->invalidation_lock); + + list_for_each_entry_safe (req, tmp, &list, list) + process_invalidation_request(cache, req); } +/*---------------------------------------------------------------- + * Main worker loop + *--------------------------------------------------------------*/ static bool is_quiescing(struct cache *cache) { - int r; - unsigned long flags; + return atomic_read(&cache->quiescing); +} - spin_lock_irqsave(&cache->lock, flags); - r = cache->quiescing; - spin_unlock_irqrestore(&cache->lock, flags); +static void ack_quiescing(struct cache *cache) +{ + if (is_quiescing(cache)) { + atomic_inc(&cache->quiescing_ack); + wake_up(&cache->quiescing_wait); + } +} - return r; +static void wait_for_quiescing_ack(struct cache *cache) +{ + wait_event(cache->quiescing_wait, atomic_read(&cache->quiescing_ack)); +} + +static void start_quiescing(struct cache *cache) +{ + atomic_inc(&cache->quiescing); + wait_for_quiescing_ack(cache); +} + +static void stop_quiescing(struct cache *cache) +{ + atomic_set(&cache->quiescing, 0); + atomic_set(&cache->quiescing_ack, 0); } static void wait_for_migrations(struct cache *cache) @@ -1412,7 +1679,8 @@ static int more_work(struct cache *cache) !bio_list_empty(&cache->deferred_writethrough_bios) || !list_empty(&cache->quiesced_migrations) || !list_empty(&cache->completed_migrations) || - !list_empty(&cache->need_commit_migrations); + !list_empty(&cache->need_commit_migrations) || + cache->invalidate; } static void do_worker(struct work_struct *ws) @@ -1420,16 +1688,16 @@ static void do_worker(struct work_struct *ws) struct cache *cache = container_of(ws, struct cache, worker); do { - if (!is_quiescing(cache)) + if (!is_quiescing(cache)) { + writeback_some_dirty_blocks(cache); + process_deferred_writethrough_bios(cache); process_deferred_bios(cache); + process_invalidation_requests(cache); + } process_migrations(cache, &cache->quiesced_migrations, issue_copy); process_migrations(cache, &cache->completed_migrations, complete_migration); - writeback_some_dirty_blocks(cache); - - process_deferred_writethrough_bios(cache); - if (commit_if_needed(cache)) { process_deferred_flush_bios(cache, false); @@ -1442,6 +1710,9 @@ static void do_worker(struct work_struct *ws) process_migrations(cache, &cache->need_commit_migrations, migration_success_post_commit); } + + ack_quiescing(cache); + } while (more_work(cache)); } @@ -1715,7 +1986,7 @@ static int parse_block_size(struct cache_args *ca, struct dm_arg_set *as, static void init_features(struct cache_features *cf) { cf->mode = CM_WRITE; - cf->write_through = false; + cf->io_mode = CM_IO_WRITEBACK; } static int parse_features(struct cache_args *ca, struct dm_arg_set *as, @@ -1740,10 +2011,13 @@ static int parse_features(struct cache_args *ca, struct dm_arg_set *as, arg = dm_shift_arg(as); if (!strcasecmp(arg, "writeback")) - cf->write_through = false; + cf->io_mode = CM_IO_WRITEBACK; else if (!strcasecmp(arg, "writethrough")) - cf->write_through = true; + cf->io_mode = CM_IO_WRITETHROUGH; + + else if (!strcasecmp(arg, "passthrough")) + cf->io_mode = CM_IO_PASSTHROUGH; else { *error = "Unrecognised cache feature requested"; @@ -1872,14 +2146,15 @@ static int set_config_values(struct cache *cache, int argc, const char **argv) static int create_cache_policy(struct cache *cache, struct cache_args *ca, char **error) { - cache->policy = dm_cache_policy_create(ca->policy_name, - cache->cache_size, - cache->origin_sectors, - cache->sectors_per_block); - if (!cache->policy) { + struct dm_cache_policy *p = dm_cache_policy_create(ca->policy_name, + cache->cache_size, + cache->origin_sectors, + cache->sectors_per_block); + if (IS_ERR(p)) { *error = "Error creating cache's policy"; - return -ENOMEM; + return PTR_ERR(p); } + cache->policy = p; return 0; } @@ -1995,6 +2270,22 @@ static int cache_create(struct cache_args *ca, struct cache **result) } cache->cmd = cmd; + if (passthrough_mode(&cache->features)) { + bool all_clean; + + r = dm_cache_metadata_all_clean(cache->cmd, &all_clean); + if (r) { + *error = "dm_cache_metadata_all_clean() failed"; + goto bad; + } + + if (!all_clean) { + *error = "Cannot enter passthrough mode unless all blocks are clean"; + r = -EINVAL; + goto bad; + } + } + spin_lock_init(&cache->lock); bio_list_init(&cache->deferred_bios); bio_list_init(&cache->deferred_flush_bios); @@ -2005,6 +2296,10 @@ static int cache_create(struct cache_args *ca, struct cache **result) atomic_set(&cache->nr_migrations, 0); init_waitqueue_head(&cache->migration_wait); + init_waitqueue_head(&cache->quiescing_wait); + atomic_set(&cache->quiescing, 0); + atomic_set(&cache->quiescing_ack, 0); + r = -ENOMEM; cache->nr_dirty = 0; cache->dirty_bitset = alloc_bitset(from_cblock(cache->cache_size)); @@ -2064,7 +2359,7 @@ static int cache_create(struct cache_args *ca, struct cache **result) cache->need_tick_bio = true; cache->sized = false; - cache->quiescing = false; + cache->invalidate = false; cache->commit_requested = false; cache->loaded_mappings = false; cache->loaded_discards = false; @@ -2078,6 +2373,9 @@ static int cache_create(struct cache_args *ca, struct cache **result) atomic_set(&cache->stats.commit_count, 0); atomic_set(&cache->stats.discard_count, 0); + spin_lock_init(&cache->invalidation_lock); + INIT_LIST_HEAD(&cache->invalidation_requests); + *result = cache; return 0; @@ -2207,17 +2505,37 @@ static int cache_map(struct dm_target *ti, struct bio *bio) return DM_MAPIO_SUBMITTED; } + r = DM_MAPIO_REMAPPED; switch (lookup_result.op) { case POLICY_HIT: - inc_hit_counter(cache, bio); - pb->all_io_entry = dm_deferred_entry_inc(cache->all_io_ds); + if (passthrough_mode(&cache->features)) { + if (bio_data_dir(bio) == WRITE) { + /* + * We need to invalidate this block, so + * defer for the worker thread. + */ + cell_defer(cache, cell, true); + r = DM_MAPIO_SUBMITTED; + + } else { + pb->all_io_entry = dm_deferred_entry_inc(cache->all_io_ds); + inc_miss_counter(cache, bio); + remap_to_origin_clear_discard(cache, bio, block); + + cell_defer(cache, cell, false); + } - if (is_writethrough_io(cache, bio, lookup_result.cblock)) - remap_to_origin_then_cache(cache, bio, block, lookup_result.cblock); - else - remap_to_cache_dirty(cache, bio, block, lookup_result.cblock); + } else { + inc_hit_counter(cache, bio); - cell_defer(cache, cell, false); + if (bio_data_dir(bio) == WRITE && writethrough_mode(&cache->features) && + !is_dirty(cache, lookup_result.cblock)) + remap_to_origin_then_cache(cache, bio, block, lookup_result.cblock); + else + remap_to_cache_dirty(cache, bio, block, lookup_result.cblock); + + cell_defer(cache, cell, false); + } break; case POLICY_MISS: @@ -2242,10 +2560,10 @@ static int cache_map(struct dm_target *ti, struct bio *bio) DMERR_LIMIT("%s: erroring bio: unknown policy op: %u", __func__, (unsigned) lookup_result.op); bio_io_error(bio); - return DM_MAPIO_SUBMITTED; + r = DM_MAPIO_SUBMITTED; } - return DM_MAPIO_REMAPPED; + return r; } static int cache_end_io(struct dm_target *ti, struct bio *bio, int error) @@ -2406,26 +2724,71 @@ static int load_discard(void *context, sector_t discard_block_size, return 0; } +static dm_cblock_t get_cache_dev_size(struct cache *cache) +{ + sector_t size = get_dev_size(cache->cache_dev); + (void) sector_div(size, cache->sectors_per_block); + return to_cblock(size); +} + +static bool can_resize(struct cache *cache, dm_cblock_t new_size) +{ + if (from_cblock(new_size) > from_cblock(cache->cache_size)) + return true; + + /* + * We can't drop a dirty block when shrinking the cache. + */ + while (from_cblock(new_size) < from_cblock(cache->cache_size)) { + new_size = to_cblock(from_cblock(new_size) + 1); + if (is_dirty(cache, new_size)) { + DMERR("unable to shrink cache; cache block %llu is dirty", + (unsigned long long) from_cblock(new_size)); + return false; + } + } + + return true; +} + +static int resize_cache_dev(struct cache *cache, dm_cblock_t new_size) +{ + int r; + + r = dm_cache_resize(cache->cmd, cache->cache_size); + if (r) { + DMERR("could not resize cache metadata"); + return r; + } + + cache->cache_size = new_size; + + return 0; +} + static int cache_preresume(struct dm_target *ti) { int r = 0; struct cache *cache = ti->private; - sector_t actual_cache_size = get_dev_size(cache->cache_dev); - (void) sector_div(actual_cache_size, cache->sectors_per_block); + dm_cblock_t csize = get_cache_dev_size(cache); /* * Check to see if the cache has resized. */ - if (from_cblock(cache->cache_size) != actual_cache_size || !cache->sized) { - cache->cache_size = to_cblock(actual_cache_size); - - r = dm_cache_resize(cache->cmd, cache->cache_size); - if (r) { - DMERR("could not resize cache metadata"); + if (!cache->sized) { + r = resize_cache_dev(cache, csize); + if (r) return r; - } cache->sized = true; + + } else if (csize != cache->cache_size) { + if (!can_resize(cache, csize)) + return -EINVAL; + + r = resize_cache_dev(cache, csize); + if (r) + return r; } if (!cache->loaded_mappings) { @@ -2518,10 +2881,19 @@ static void cache_status(struct dm_target *ti, status_type_t type, (unsigned long long) from_cblock(residency), cache->nr_dirty); - if (cache->features.write_through) + if (writethrough_mode(&cache->features)) DMEMIT("1 writethrough "); - else - DMEMIT("0 "); + + else if (passthrough_mode(&cache->features)) + DMEMIT("1 passthrough "); + + else if (writeback_mode(&cache->features)) + DMEMIT("1 writeback "); + + else { + DMERR("internal error: unknown io mode: %d", (int) cache->features.io_mode); + goto err; + } DMEMIT("2 migration_threshold %llu ", (unsigned long long) cache->migration_threshold); if (sz < maxlen) { @@ -2553,7 +2925,128 @@ err: } /* - * Supports <key> <value>. + * A cache block range can take two forms: + * + * i) A single cblock, eg. '3456' + * ii) A begin and end cblock with dots between, eg. 123-234 + */ +static int parse_cblock_range(struct cache *cache, const char *str, + struct cblock_range *result) +{ + char dummy; + uint64_t b, e; + int r; + + /* + * Try and parse form (ii) first. + */ + r = sscanf(str, "%llu-%llu%c", &b, &e, &dummy); + if (r < 0) + return r; + + if (r == 2) { + result->begin = to_cblock(b); + result->end = to_cblock(e); + return 0; + } + + /* + * That didn't work, try form (i). + */ + r = sscanf(str, "%llu%c", &b, &dummy); + if (r < 0) + return r; + + if (r == 1) { + result->begin = to_cblock(b); + result->end = to_cblock(from_cblock(result->begin) + 1u); + return 0; + } + + DMERR("invalid cblock range '%s'", str); + return -EINVAL; +} + +static int validate_cblock_range(struct cache *cache, struct cblock_range *range) +{ + uint64_t b = from_cblock(range->begin); + uint64_t e = from_cblock(range->end); + uint64_t n = from_cblock(cache->cache_size); + + if (b >= n) { + DMERR("begin cblock out of range: %llu >= %llu", b, n); + return -EINVAL; + } + + if (e > n) { + DMERR("end cblock out of range: %llu > %llu", e, n); + return -EINVAL; + } + + if (b >= e) { + DMERR("invalid cblock range: %llu >= %llu", b, e); + return -EINVAL; + } + + return 0; +} + +static int request_invalidation(struct cache *cache, struct cblock_range *range) +{ + struct invalidation_request req; + + INIT_LIST_HEAD(&req.list); + req.cblocks = range; + atomic_set(&req.complete, 0); + req.err = 0; + init_waitqueue_head(&req.result_wait); + + spin_lock(&cache->invalidation_lock); + list_add(&req.list, &cache->invalidation_requests); + spin_unlock(&cache->invalidation_lock); + wake_worker(cache); + + wait_event(req.result_wait, atomic_read(&req.complete)); + return req.err; +} + +static int process_invalidate_cblocks_message(struct cache *cache, unsigned count, + const char **cblock_ranges) +{ + int r = 0; + unsigned i; + struct cblock_range range; + + if (!passthrough_mode(&cache->features)) { + DMERR("cache has to be in passthrough mode for invalidation"); + return -EPERM; + } + + for (i = 0; i < count; i++) { + r = parse_cblock_range(cache, cblock_ranges[i], &range); + if (r) + break; + + r = validate_cblock_range(cache, &range); + if (r) + break; + + /* + * Pass begin and end origin blocks to the worker and wake it. + */ + r = request_invalidation(cache, &range); + if (r) + break; + } + + return r; +} + +/* + * Supports + * "<key> <value>" + * and + * "invalidate_cblocks [(<begin>)|(<begin>-<end>)]* * * The key migration_threshold is supported by the cache target core. */ @@ -2561,6 +3054,12 @@ static int cache_message(struct dm_target *ti, unsigned argc, char **argv) { struct cache *cache = ti->private; + if (!argc) + return -EINVAL; + + if (!strcasecmp(argv[0], "invalidate_cblocks")) + return process_invalidate_cblocks_message(cache, argc - 1, (const char **) argv + 1); + if (argc != 2) return -EINVAL; @@ -2630,7 +3129,7 @@ static void cache_io_hints(struct dm_target *ti, struct queue_limits *limits) static struct target_type cache_target = { .name = "cache", - .version = {1, 1, 1}, + .version = {1, 2, 0}, .module = THIS_MODULE, .ctr = cache_ctr, .dtr = cache_dtr, diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c index 0fce0bc..81b0fa6 100644 --- a/drivers/md/dm-crypt.c +++ b/drivers/md/dm-crypt.c @@ -2,6 +2,7 @@ * Copyright (C) 2003 Christophe Saout <christophe@saout.de> * Copyright (C) 2004 Clemens Fruhwirth <clemens@endorphin.org> * Copyright (C) 2006-2009 Red Hat, Inc. All rights reserved. + * Copyright (C) 2013 Milan Broz <gmazyland@gmail.com> * * This file is released under the GPL. */ @@ -98,6 +99,13 @@ struct iv_lmk_private { u8 *seed; }; +#define TCW_WHITENING_SIZE 16 +struct iv_tcw_private { + struct crypto_shash *crc32_tfm; + u8 *iv_seed; + u8 *whitening; +}; + /* * Crypt: maps a linear range of a block device * and encrypts / decrypts at the same time. @@ -139,6 +147,7 @@ struct crypt_config { struct iv_essiv_private essiv; struct iv_benbi_private benbi; struct iv_lmk_private lmk; + struct iv_tcw_private tcw; } iv_gen_private; sector_t iv_offset; unsigned int iv_size; @@ -171,7 +180,8 @@ struct crypt_config { unsigned long flags; unsigned int key_size; - unsigned int key_parts; + unsigned int key_parts; /* independent parts in key buffer */ + unsigned int key_extra_size; /* additional keys length */ u8 key[0]; }; @@ -230,6 +240,16 @@ static struct crypto_ablkcipher *any_tfm(struct crypt_config *cc) * version 3: the same as version 2 with additional IV seed * (it uses 65 keys, last key is used as IV seed) * + * tcw: Compatible implementation of the block chaining mode used + * by the TrueCrypt device encryption system (prior to version 4.1). + * For more info see: http://www.truecrypt.org + * It operates on full 512 byte sectors and uses CBC + * with an IV derived from initial key and the sector number. + * In addition, whitening value is applied on every sector, whitening + * is calculated from initial key, sector number and mixed using CRC32. + * Note that this encryption scheme is vulnerable to watermarking attacks + * and should be used for old compatible containers access only. + * * plumb: unimplemented, see: * http://article.gmane.org/gmane.linux.kernel.device-mapper.dm-crypt/454 */ @@ -530,7 +550,7 @@ static int crypt_iv_lmk_one(struct crypt_config *cc, u8 *iv, char ctx[crypto_shash_descsize(lmk->hash_tfm)]; } sdesc; struct md5_state md5state; - u32 buf[4]; + __le32 buf[4]; int i, r; sdesc.desc.tfm = lmk->hash_tfm; @@ -608,6 +628,153 @@ static int crypt_iv_lmk_post(struct crypt_config *cc, u8 *iv, return r; } +static void crypt_iv_tcw_dtr(struct crypt_config *cc) +{ + struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; + + kzfree(tcw->iv_seed); + tcw->iv_seed = NULL; + kzfree(tcw->whitening); + tcw->whitening = NULL; + + if (tcw->crc32_tfm && !IS_ERR(tcw->crc32_tfm)) + crypto_free_shash(tcw->crc32_tfm); + tcw->crc32_tfm = NULL; +} + +static int crypt_iv_tcw_ctr(struct crypt_config *cc, struct dm_target *ti, + const char *opts) +{ + struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; + + if (cc->key_size <= (cc->iv_size + TCW_WHITENING_SIZE)) { + ti->error = "Wrong key size for TCW"; + return -EINVAL; + } + + tcw->crc32_tfm = crypto_alloc_shash("crc32", 0, 0); + if (IS_ERR(tcw->crc32_tfm)) { + ti->error = "Error initializing CRC32 in TCW"; + return PTR_ERR(tcw->crc32_tfm); + } + + tcw->iv_seed = kzalloc(cc->iv_size, GFP_KERNEL); + tcw->whitening = kzalloc(TCW_WHITENING_SIZE, GFP_KERNEL); + if (!tcw->iv_seed || !tcw->whitening) { + crypt_iv_tcw_dtr(cc); + ti->error = "Error allocating seed storage in TCW"; + return -ENOMEM; + } + + return 0; +} + +static int crypt_iv_tcw_init(struct crypt_config *cc) +{ + struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; + int key_offset = cc->key_size - cc->iv_size - TCW_WHITENING_SIZE; + + memcpy(tcw->iv_seed, &cc->key[key_offset], cc->iv_size); + memcpy(tcw->whitening, &cc->key[key_offset + cc->iv_size], + TCW_WHITENING_SIZE); + + return 0; +} + +static int crypt_iv_tcw_wipe(struct crypt_config *cc) +{ + struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; + + memset(tcw->iv_seed, 0, cc->iv_size); + memset(tcw->whitening, 0, TCW_WHITENING_SIZE); + + return 0; +} + +static int crypt_iv_tcw_whitening(struct crypt_config *cc, + struct dm_crypt_request *dmreq, + u8 *data) +{ + struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; + u64 sector = cpu_to_le64((u64)dmreq->iv_sector); + u8 buf[TCW_WHITENING_SIZE]; + struct { + struct shash_desc desc; + char ctx[crypto_shash_descsize(tcw->crc32_tfm)]; + } sdesc; + int i, r; + + /* xor whitening with sector number */ + memcpy(buf, tcw->whitening, TCW_WHITENING_SIZE); + crypto_xor(buf, (u8 *)§or, 8); + crypto_xor(&buf[8], (u8 *)§or, 8); + + /* calculate crc32 for every 32bit part and xor it */ + sdesc.desc.tfm = tcw->crc32_tfm; + sdesc.desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP; + for (i = 0; i < 4; i++) { + r = crypto_shash_init(&sdesc.desc); + if (r) + goto out; + r = crypto_shash_update(&sdesc.desc, &buf[i * 4], 4); + if (r) + goto out; + r = crypto_shash_final(&sdesc.desc, &buf[i * 4]); + if (r) + goto out; + } + crypto_xor(&buf[0], &buf[12], 4); + crypto_xor(&buf[4], &buf[8], 4); + + /* apply whitening (8 bytes) to whole sector */ + for (i = 0; i < ((1 << SECTOR_SHIFT) / 8); i++) + crypto_xor(data + i * 8, buf, 8); +out: + memset(buf, 0, sizeof(buf)); + return r; +} + +static int crypt_iv_tcw_gen(struct crypt_config *cc, u8 *iv, + struct dm_crypt_request *dmreq) +{ + struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; + u64 sector = cpu_to_le64((u64)dmreq->iv_sector); + u8 *src; + int r = 0; + + /* Remove whitening from ciphertext */ + if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) { + src = kmap_atomic(sg_page(&dmreq->sg_in)); + r = crypt_iv_tcw_whitening(cc, dmreq, src + dmreq->sg_in.offset); + kunmap_atomic(src); + } + + /* Calculate IV */ + memcpy(iv, tcw->iv_seed, cc->iv_size); + crypto_xor(iv, (u8 *)§or, 8); + if (cc->iv_size > 8) + crypto_xor(&iv[8], (u8 *)§or, cc->iv_size - 8); + + return r; +} + +static int crypt_iv_tcw_post(struct crypt_config *cc, u8 *iv, + struct dm_crypt_request *dmreq) +{ + u8 *dst; + int r; + + if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) + return 0; + + /* Apply whitening on ciphertext */ + dst = kmap_atomic(sg_page(&dmreq->sg_out)); + r = crypt_iv_tcw_whitening(cc, dmreq, dst + dmreq->sg_out.offset); + kunmap_atomic(dst); + + return r; +} + static struct crypt_iv_operations crypt_iv_plain_ops = { .generator = crypt_iv_plain_gen }; @@ -643,6 +810,15 @@ static struct crypt_iv_operations crypt_iv_lmk_ops = { .post = crypt_iv_lmk_post }; +static struct crypt_iv_operations crypt_iv_tcw_ops = { + .ctr = crypt_iv_tcw_ctr, + .dtr = crypt_iv_tcw_dtr, + .init = crypt_iv_tcw_init, + .wipe = crypt_iv_tcw_wipe, + .generator = crypt_iv_tcw_gen, + .post = crypt_iv_tcw_post +}; + static void crypt_convert_init(struct crypt_config *cc, struct convert_context *ctx, struct bio *bio_out, struct bio *bio_in, @@ -774,7 +950,7 @@ static int crypt_convert(struct crypt_config *cc, /* async */ case -EBUSY: wait_for_completion(&ctx->restart); - INIT_COMPLETION(ctx->restart); + reinit_completion(&ctx->restart); /* fall through*/ case -EINPROGRESS: this_cc->req = NULL; @@ -1274,9 +1450,12 @@ static int crypt_alloc_tfms(struct crypt_config *cc, char *ciphermode) static int crypt_setkey_allcpus(struct crypt_config *cc) { - unsigned subkey_size = cc->key_size >> ilog2(cc->tfms_count); + unsigned subkey_size; int err = 0, i, r; + /* Ignore extra keys (which are used for IV etc) */ + subkey_size = (cc->key_size - cc->key_extra_size) >> ilog2(cc->tfms_count); + for (i = 0; i < cc->tfms_count; i++) { r = crypto_ablkcipher_setkey(cc->tfms[i], cc->key + (i * subkey_size), @@ -1409,6 +1588,7 @@ static int crypt_ctr_cipher(struct dm_target *ti, return -EINVAL; } cc->key_parts = cc->tfms_count; + cc->key_extra_size = 0; cc->cipher = kstrdup(cipher, GFP_KERNEL); if (!cc->cipher) @@ -1460,13 +1640,6 @@ static int crypt_ctr_cipher(struct dm_target *ti, goto bad; } - /* Initialize and set key */ - ret = crypt_set_key(cc, key); - if (ret < 0) { - ti->error = "Error decoding and setting key"; - goto bad; - } - /* Initialize IV */ cc->iv_size = crypto_ablkcipher_ivsize(any_tfm(cc)); if (cc->iv_size) @@ -1493,18 +1666,33 @@ static int crypt_ctr_cipher(struct dm_target *ti, cc->iv_gen_ops = &crypt_iv_null_ops; else if (strcmp(ivmode, "lmk") == 0) { cc->iv_gen_ops = &crypt_iv_lmk_ops; - /* Version 2 and 3 is recognised according + /* + * Version 2 and 3 is recognised according * to length of provided multi-key string. * If present (version 3), last key is used as IV seed. + * All keys (including IV seed) are always the same size. */ - if (cc->key_size % cc->key_parts) + if (cc->key_size % cc->key_parts) { cc->key_parts++; + cc->key_extra_size = cc->key_size / cc->key_parts; + } + } else if (strcmp(ivmode, "tcw") == 0) { + cc->iv_gen_ops = &crypt_iv_tcw_ops; + cc->key_parts += 2; /* IV + whitening */ + cc->key_extra_size = cc->iv_size + TCW_WHITENING_SIZE; } else { ret = -EINVAL; ti->error = "Invalid IV mode"; goto bad; } + /* Initialize and set key */ + ret = crypt_set_key(cc, key); + if (ret < 0) { + ti->error = "Error decoding and setting key"; + goto bad; + } + /* Allocate IV */ if (cc->iv_gen_ops && cc->iv_gen_ops->ctr) { ret = cc->iv_gen_ops->ctr(cc, ti, ivopts); @@ -1817,7 +2005,7 @@ static int crypt_iterate_devices(struct dm_target *ti, static struct target_type crypt_target = { .name = "crypt", - .version = {1, 12, 1}, + .version = {1, 13, 0}, .module = THIS_MODULE, .ctr = crypt_ctr, .dtr = crypt_dtr, diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c index afe0814..5152142 100644 --- a/drivers/md/dm-ioctl.c +++ b/drivers/md/dm-ioctl.c @@ -57,7 +57,7 @@ struct vers_iter { static struct list_head _name_buckets[NUM_BUCKETS]; static struct list_head _uuid_buckets[NUM_BUCKETS]; -static void dm_hash_remove_all(int keep_open_devices); +static void dm_hash_remove_all(bool keep_open_devices, bool mark_deferred, bool only_deferred); /* * Guards access to both hash tables. @@ -86,7 +86,7 @@ static int dm_hash_init(void) static void dm_hash_exit(void) { - dm_hash_remove_all(0); + dm_hash_remove_all(false, false, false); } /*----------------------------------------------------------------- @@ -276,7 +276,7 @@ static struct dm_table *__hash_remove(struct hash_cell *hc) return table; } -static void dm_hash_remove_all(int keep_open_devices) +static void dm_hash_remove_all(bool keep_open_devices, bool mark_deferred, bool only_deferred) { int i, dev_skipped; struct hash_cell *hc; @@ -293,7 +293,8 @@ retry: md = hc->md; dm_get(md); - if (keep_open_devices && dm_lock_for_deletion(md)) { + if (keep_open_devices && + dm_lock_for_deletion(md, mark_deferred, only_deferred)) { dm_put(md); dev_skipped++; continue; @@ -450,6 +451,11 @@ static struct mapped_device *dm_hash_rename(struct dm_ioctl *param, return md; } +void dm_deferred_remove(void) +{ + dm_hash_remove_all(true, false, true); +} + /*----------------------------------------------------------------- * Implementation of the ioctl commands *---------------------------------------------------------------*/ @@ -461,7 +467,7 @@ typedef int (*ioctl_fn)(struct dm_ioctl *param, size_t param_size); static int remove_all(struct dm_ioctl *param, size_t param_size) { - dm_hash_remove_all(1); + dm_hash_remove_all(true, !!(param->flags & DM_DEFERRED_REMOVE), false); param->data_size = 0; return 0; } @@ -683,6 +689,9 @@ static void __dev_status(struct mapped_device *md, struct dm_ioctl *param) if (dm_suspended_md(md)) param->flags |= DM_SUSPEND_FLAG; + if (dm_test_deferred_remove_flag(md)) + param->flags |= DM_DEFERRED_REMOVE; + param->dev = huge_encode_dev(disk_devt(disk)); /* @@ -832,8 +841,13 @@ static int dev_remove(struct dm_ioctl *param, size_t param_size) /* * Ensure the device is not open and nothing further can open it. */ - r = dm_lock_for_deletion(md); + r = dm_lock_for_deletion(md, !!(param->flags & DM_DEFERRED_REMOVE), false); if (r) { + if (r == -EBUSY && param->flags & DM_DEFERRED_REMOVE) { + up_write(&_hash_lock); + dm_put(md); + return 0; + } DMDEBUG_LIMIT("unable to remove open device %s", hc->name); up_write(&_hash_lock); dm_put(md); @@ -848,6 +862,8 @@ static int dev_remove(struct dm_ioctl *param, size_t param_size) dm_table_destroy(t); } + param->flags &= ~DM_DEFERRED_REMOVE; + if (!dm_kobject_uevent(md, KOBJ_REMOVE, param->event_nr)) param->flags |= DM_UEVENT_GENERATED_FLAG; @@ -1469,6 +1485,14 @@ static int message_for_md(struct mapped_device *md, unsigned argc, char **argv, if (**argv != '@') return 2; /* no '@' prefix, deliver to target */ + if (!strcasecmp(argv[0], "@cancel_deferred_remove")) { + if (argc != 1) { + DMERR("Invalid arguments for @cancel_deferred_remove"); + return -EINVAL; + } + return dm_cancel_deferred_remove(md); + } + r = dm_stats_message(md, argc, argv, result, maxlen); if (r < 2) return r; diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c index de570a5..6eb9dc9 100644 --- a/drivers/md/dm-mpath.c +++ b/drivers/md/dm-mpath.c @@ -87,6 +87,7 @@ struct multipath { unsigned queue_if_no_path:1; /* Queue I/O if last path fails? */ unsigned saved_queue_if_no_path:1; /* Saved state during suspension */ unsigned retain_attached_hw_handler:1; /* If there's already a hw_handler present, don't change it. */ + unsigned pg_init_disabled:1; /* pg_init is not currently allowed */ unsigned pg_init_retries; /* Number of times to retry pg_init */ unsigned pg_init_count; /* Number of times pg_init called */ @@ -390,13 +391,16 @@ static int map_io(struct multipath *m, struct request *clone, if (was_queued) m->queue_size--; - if ((pgpath && m->queue_io) || - (!pgpath && m->queue_if_no_path)) { + if (m->pg_init_required) { + if (!m->pg_init_in_progress) + queue_work(kmultipathd, &m->process_queued_ios); + r = DM_MAPIO_REQUEUE; + } else if ((pgpath && m->queue_io) || + (!pgpath && m->queue_if_no_path)) { /* Queue for the daemon to resubmit */ list_add_tail(&clone->queuelist, &m->queued_ios); m->queue_size++; - if ((m->pg_init_required && !m->pg_init_in_progress) || - !m->queue_io) + if (!m->queue_io) queue_work(kmultipathd, &m->process_queued_ios); pgpath = NULL; r = DM_MAPIO_SUBMITTED; @@ -497,7 +501,8 @@ static void process_queued_ios(struct work_struct *work) (!pgpath && !m->queue_if_no_path)) must_queue = 0; - if (m->pg_init_required && !m->pg_init_in_progress && pgpath) + if (m->pg_init_required && !m->pg_init_in_progress && pgpath && + !m->pg_init_disabled) __pg_init_all_paths(m); spin_unlock_irqrestore(&m->lock, flags); @@ -942,10 +947,20 @@ static void multipath_wait_for_pg_init_completion(struct multipath *m) static void flush_multipath_work(struct multipath *m) { + unsigned long flags; + + spin_lock_irqsave(&m->lock, flags); + m->pg_init_disabled = 1; + spin_unlock_irqrestore(&m->lock, flags); + flush_workqueue(kmpath_handlerd); multipath_wait_for_pg_init_completion(m); flush_workqueue(kmultipathd); flush_work(&m->trigger_event); + + spin_lock_irqsave(&m->lock, flags); + m->pg_init_disabled = 0; + spin_unlock_irqrestore(&m->lock, flags); } static void multipath_dtr(struct dm_target *ti) @@ -1164,7 +1179,7 @@ static int pg_init_limit_reached(struct multipath *m, struct pgpath *pgpath) spin_lock_irqsave(&m->lock, flags); - if (m->pg_init_count <= m->pg_init_retries) + if (m->pg_init_count <= m->pg_init_retries && !m->pg_init_disabled) m->pg_init_required = 1; else limit_reached = 1; @@ -1665,6 +1680,11 @@ static int multipath_busy(struct dm_target *ti) spin_lock_irqsave(&m->lock, flags); + /* pg_init in progress, requeue until done */ + if (m->pg_init_in_progress) { + busy = 1; + goto out; + } /* Guess which priority_group will be used at next mapping time */ if (unlikely(!m->current_pgpath && m->next_pg)) pg = m->next_pg; @@ -1714,7 +1734,7 @@ out: *---------------------------------------------------------------*/ static struct target_type multipath_target = { .name = "multipath", - .version = {1, 5, 1}, + .version = {1, 6, 0}, .module = THIS_MODULE, .ctr = multipath_ctr, .dtr = multipath_dtr, diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c index 8f87835..465f08c 100644 --- a/drivers/md/dm-table.c +++ b/drivers/md/dm-table.c @@ -545,14 +545,28 @@ static int adjoin(struct dm_table *table, struct dm_target *ti) /* * Used to dynamically allocate the arg array. + * + * We do first allocation with GFP_NOIO because dm-mpath and dm-thin must + * process messages even if some device is suspended. These messages have a + * small fixed number of arguments. + * + * On the other hand, dm-switch needs to process bulk data using messages and + * excessive use of GFP_NOIO could cause trouble. */ static char **realloc_argv(unsigned *array_size, char **old_argv) { char **argv; unsigned new_size; + gfp_t gfp; - new_size = *array_size ? *array_size * 2 : 64; - argv = kmalloc(new_size * sizeof(*argv), GFP_KERNEL); + if (*array_size) { + new_size = *array_size * 2; + gfp = GFP_KERNEL; + } else { + new_size = 8; + gfp = GFP_NOIO; + } + argv = kmalloc(new_size * sizeof(*argv), gfp); if (argv) { memcpy(argv, old_argv, *array_size * sizeof(*argv)); *array_size = new_size; @@ -1548,8 +1562,11 @@ int dm_table_resume_targets(struct dm_table *t) continue; r = ti->type->preresume(ti); - if (r) + if (r) { + DMERR("%s: %s: preresume failed, error = %d", + dm_device_name(t->md), ti->type->name, r); return r; + } } for (i = 0; i < t->num_targets; i++) { diff --git a/drivers/md/dm.c b/drivers/md/dm.c index b3e26c7..0704c52 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -49,6 +49,11 @@ static unsigned int _major = 0; static DEFINE_IDR(_minor_idr); static DEFINE_SPINLOCK(_minor_lock); + +static void do_deferred_remove(struct work_struct *w); + +static DECLARE_WORK(deferred_remove_work, do_deferred_remove); + /* * For bio-based dm. * One of these is allocated per bio. @@ -116,6 +121,7 @@ EXPORT_SYMBOL_GPL(dm_get_rq_mapinfo); #define DMF_DELETING 4 #define DMF_NOFLUSH_SUSPENDING 5 #define DMF_MERGE_IS_OPTIONAL 6 +#define DMF_DEFERRED_REMOVE 7 /* * A dummy definition to make RCU happy. @@ -299,6 +305,8 @@ out_free_io_cache: static void local_exit(void) { + flush_scheduled_work(); + kmem_cache_destroy(_rq_tio_cache); kmem_cache_destroy(_io_cache); unregister_blkdev(_major, _name); @@ -404,7 +412,10 @@ static void dm_blk_close(struct gendisk *disk, fmode_t mode) spin_lock(&_minor_lock); - atomic_dec(&md->open_count); + if (atomic_dec_and_test(&md->open_count) && + (test_bit(DMF_DEFERRED_REMOVE, &md->flags))) + schedule_work(&deferred_remove_work); + dm_put(md); spin_unlock(&_minor_lock); @@ -418,14 +429,18 @@ int dm_open_count(struct mapped_device *md) /* * Guarantees nothing is using the device before it's deleted. */ -int dm_lock_for_deletion(struct mapped_device *md) +int dm_lock_for_deletion(struct mapped_device *md, bool mark_deferred, bool only_deferred) { int r = 0; spin_lock(&_minor_lock); - if (dm_open_count(md)) + if (dm_open_count(md)) { r = -EBUSY; + if (mark_deferred) + set_bit(DMF_DEFERRED_REMOVE, &md->flags); + } else if (only_deferred && !test_bit(DMF_DEFERRED_REMOVE, &md->flags)) + r = -EEXIST; else set_bit(DMF_DELETING, &md->flags); @@ -434,6 +449,27 @@ int dm_lock_for_deletion(struct mapped_device *md) return r; } +int dm_cancel_deferred_remove(struct mapped_device *md) +{ + int r = 0; + + spin_lock(&_minor_lock); + + if (test_bit(DMF_DELETING, &md->flags)) + r = -EBUSY; + else + clear_bit(DMF_DEFERRED_REMOVE, &md->flags); + + spin_unlock(&_minor_lock); + + return r; +} + +static void do_deferred_remove(struct work_struct *w) +{ + dm_deferred_remove(); +} + sector_t dm_get_size(struct mapped_device *md) { return get_capacity(md->disk); @@ -2894,6 +2930,11 @@ int dm_suspended_md(struct mapped_device *md) return test_bit(DMF_SUSPENDED, &md->flags); } +int dm_test_deferred_remove_flag(struct mapped_device *md) +{ + return test_bit(DMF_DEFERRED_REMOVE, &md->flags); +} + int dm_suspended(struct dm_target *ti) { return dm_suspended_md(dm_table_get_md(ti->table)); diff --git a/drivers/md/dm.h b/drivers/md/dm.h index 1d1ad7b..c57ba55 100644 --- a/drivers/md/dm.h +++ b/drivers/md/dm.h @@ -129,6 +129,16 @@ int dm_deleting_md(struct mapped_device *md); int dm_suspended_md(struct mapped_device *md); /* + * Test if the device is scheduled for deferred remove. + */ +int dm_test_deferred_remove_flag(struct mapped_device *md); + +/* + * Try to remove devices marked for deferred removal. + */ +void dm_deferred_remove(void); + +/* * The device-mapper can be driven through one of two interfaces; * ioctl or filesystem, depending which patch you have applied. */ @@ -158,7 +168,8 @@ void dm_stripe_exit(void); void dm_destroy(struct mapped_device *md); void dm_destroy_immediate(struct mapped_device *md); int dm_open_count(struct mapped_device *md); -int dm_lock_for_deletion(struct mapped_device *md); +int dm_lock_for_deletion(struct mapped_device *md, bool mark_deferred, bool only_deferred); +int dm_cancel_deferred_remove(struct mapped_device *md); int dm_request_based(struct mapped_device *md); sector_t dm_get_size(struct mapped_device *md); struct dm_stats *dm_get_stats(struct mapped_device *md); diff --git a/drivers/md/md.c b/drivers/md/md.c index 7521190..8766eab 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -3515,7 +3515,7 @@ level_store(struct mddev *mddev, const char *buf, size_t len) printk(KERN_WARNING "md: cannot register extra attributes for %s\n", mdname(mddev)); - mddev->sysfs_action = sysfs_get_dirent(mddev->kobj.sd, NULL, "sync_action"); + mddev->sysfs_action = sysfs_get_dirent(mddev->kobj.sd, "sync_action"); } if (mddev->pers->sync_request != NULL && pers->sync_request == NULL) { diff --git a/drivers/md/md.h b/drivers/md/md.h index c96456c..2f5cc8a 100644 --- a/drivers/md/md.h +++ b/drivers/md/md.h @@ -501,7 +501,7 @@ extern struct attribute_group md_bitmap_group; static inline struct sysfs_dirent *sysfs_get_dirent_safe(struct sysfs_dirent *sd, char *name) { if (sd) - return sysfs_get_dirent(sd, NULL, name); + return sysfs_get_dirent(sd, name); return sd; } static inline void sysfs_notify_dirent_safe(struct sysfs_dirent *sd) diff --git a/drivers/md/persistent-data/dm-array.c b/drivers/md/persistent-data/dm-array.c index 172147e..af96e24 100644 --- a/drivers/md/persistent-data/dm-array.c +++ b/drivers/md/persistent-data/dm-array.c @@ -509,15 +509,18 @@ static int grow_add_tail_block(struct resize *resize) static int grow_needs_more_blocks(struct resize *resize) { int r; + unsigned old_nr_blocks = resize->old_nr_full_blocks; if (resize->old_nr_entries_in_last_block > 0) { + old_nr_blocks++; + r = grow_extend_tail_block(resize, resize->max_entries); if (r) return r; } r = insert_full_ablocks(resize->info, resize->size_of_block, - resize->old_nr_full_blocks, + old_nr_blocks, resize->new_nr_full_blocks, resize->max_entries, resize->value, &resize->root); diff --git a/drivers/md/persistent-data/dm-space-map-disk.c b/drivers/md/persistent-data/dm-space-map-disk.c index e735a6d..cfbf961 100644 --- a/drivers/md/persistent-data/dm-space-map-disk.c +++ b/drivers/md/persistent-data/dm-space-map-disk.c @@ -140,26 +140,10 @@ static int sm_disk_inc_block(struct dm_space_map *sm, dm_block_t b) static int sm_disk_dec_block(struct dm_space_map *sm, dm_block_t b) { - int r; - uint32_t old_count; enum allocation_event ev; struct sm_disk *smd = container_of(sm, struct sm_disk, sm); - r = sm_ll_dec(&smd->ll, b, &ev); - if (!r && (ev == SM_FREE)) { - /* - * It's only free if it's also free in the last - * transaction. - */ - r = sm_ll_lookup(&smd->old_ll, b, &old_count); - if (r) - return r; - - if (!old_count) - smd->nr_allocated_this_transaction--; - } - - return r; + return sm_ll_dec(&smd->ll, b, &ev); } static int sm_disk_new_block(struct dm_space_map *sm, dm_block_t *b) diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index f8b9068..7f0e17a 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -293,20 +293,6 @@ static void __release_stripe(struct r5conf *conf, struct stripe_head *sh) do_release_stripe(conf, sh); } -static struct llist_node *llist_reverse_order(struct llist_node *head) -{ - struct llist_node *new_head = NULL; - - while (head) { - struct llist_node *tmp = head; - head = head->next; - tmp->next = new_head; - new_head = tmp; - } - - return new_head; -} - /* should hold conf->device_lock already */ static int release_stripe_list(struct r5conf *conf) { |