diff options
| -rw-r--r-- | drivers/md/dm-bio-list.h | 10 | ||||
| -rw-r--r-- | drivers/md/dm-bio-record.h | 26 | ||||
| -rw-r--r-- | drivers/md/dm-crypt.c | 6 | ||||
| -rw-r--r-- | drivers/md/dm-exception-store.c | 252 | ||||
| -rw-r--r-- | drivers/md/dm-exception-store.h | 58 | ||||
| -rw-r--r-- | drivers/md/dm-io.c | 5 | ||||
| -rw-r--r-- | drivers/md/dm-log.c | 75 | ||||
| -rw-r--r-- | drivers/md/dm-path-selector.c | 21 | ||||
| -rw-r--r-- | drivers/md/dm-raid1.c | 50 | ||||
| -rw-r--r-- | drivers/md/dm-snap-persistent.c | 153 | ||||
| -rw-r--r-- | drivers/md/dm-snap-transient.c | 86 | ||||
| -rw-r--r-- | drivers/md/dm-snap.c | 384 | ||||
| -rw-r--r-- | drivers/md/dm-snap.h | 105 | ||||
| -rw-r--r-- | drivers/md/dm-table.c | 26 | ||||
| -rw-r--r-- | drivers/md/dm-target.c | 104 | ||||
| -rw-r--r-- | drivers/md/dm.c | 134 | ||||
| -rw-r--r-- | drivers/md/dm.h | 2 | ||||
| -rw-r--r-- | include/linux/device-mapper.h | 3 | ||||
| -rw-r--r-- | include/linux/dm-dirty-log.h | 13 |
19 files changed, 893 insertions, 620 deletions
diff --git a/drivers/md/dm-bio-list.h b/drivers/md/dm-bio-list.h index d4509be..345098b 100644 --- a/drivers/md/dm-bio-list.h +++ b/drivers/md/dm-bio-list.h @@ -52,6 +52,16 @@ static inline void bio_list_add(struct bio_list *bl, struct bio *bio) bl->tail = bio; } +static inline void bio_list_add_head(struct bio_list *bl, struct bio *bio) +{ + bio->bi_next = bl->head; + + bl->head = bio; + + if (!bl->tail) + bl->tail = bio; +} + static inline void bio_list_merge(struct bio_list *bl, struct bio_list *bl2) { if (!bl2->head) diff --git a/drivers/md/dm-bio-record.h b/drivers/md/dm-bio-record.h index d3ec217..3a8cfa2 100644 --- a/drivers/md/dm-bio-record.h +++ b/drivers/md/dm-bio-record.h @@ -16,30 +16,56 @@ * functions in this file help the target record and restore the * original bio state. */ + +struct dm_bio_vec_details { +#if PAGE_SIZE < 65536 + __u16 bv_len; + __u16 bv_offset; +#else + unsigned bv_len; + unsigned bv_offset; +#endif +}; + struct dm_bio_details { sector_t bi_sector; struct block_device *bi_bdev; unsigned int bi_size; unsigned short bi_idx; unsigned long bi_flags; + struct dm_bio_vec_details bi_io_vec[BIO_MAX_PAGES]; }; static inline void dm_bio_record(struct dm_bio_details *bd, struct bio *bio) { + unsigned i; + bd->bi_sector = bio->bi_sector; bd->bi_bdev = bio->bi_bdev; bd->bi_size = bio->bi_size; bd->bi_idx = bio->bi_idx; bd->bi_flags = bio->bi_flags; + + for (i = 0; i < bio->bi_vcnt; i++) { + bd->bi_io_vec[i].bv_len = bio->bi_io_vec[i].bv_len; + bd->bi_io_vec[i].bv_offset = bio->bi_io_vec[i].bv_offset; + } } static inline void dm_bio_restore(struct dm_bio_details *bd, struct bio *bio) { + unsigned i; + bio->bi_sector = bd->bi_sector; bio->bi_bdev = bd->bi_bdev; bio->bi_size = bd->bi_size; bio->bi_idx = bd->bi_idx; bio->bi_flags = bd->bi_flags; + + for (i = 0; i < bio->bi_vcnt; i++) { + bio->bi_io_vec[i].bv_len = bd->bi_io_vec[i].bv_len; + bio->bi_io_vec[i].bv_offset = bd->bi_io_vec[i].bv_offset; + } } #endif diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c index bfefd07..53394e8 100644 --- a/drivers/md/dm-crypt.c +++ b/drivers/md/dm-crypt.c @@ -1156,8 +1156,7 @@ bad_ivmode: crypto_free_ablkcipher(tfm); bad_cipher: /* Must zero key material before freeing */ - memset(cc, 0, sizeof(*cc) + cc->key_size * sizeof(u8)); - kfree(cc); + kzfree(cc); return -EINVAL; } @@ -1183,8 +1182,7 @@ static void crypt_dtr(struct dm_target *ti) dm_put_device(ti, cc->dev); /* Must zero key material before freeing */ - memset(cc, 0, sizeof(*cc) + cc->key_size * sizeof(u8)); - kfree(cc); + kzfree(cc); } static int crypt_map(struct dm_target *ti, struct bio *bio, diff --git a/drivers/md/dm-exception-store.c b/drivers/md/dm-exception-store.c index dccbfb0..a2e26c2 100644 --- a/drivers/md/dm-exception-store.c +++ b/drivers/md/dm-exception-store.c @@ -7,6 +7,7 @@ #include "dm-exception-store.h" +#include <linux/ctype.h> #include <linux/mm.h> #include <linux/pagemap.h> #include <linux/vmalloc.h> @@ -14,6 +15,257 @@ #define DM_MSG_PREFIX "snapshot exception stores" +static LIST_HEAD(_exception_store_types); +static DEFINE_SPINLOCK(_lock); + +static struct dm_exception_store_type *__find_exception_store_type(const char *name) +{ + struct dm_exception_store_type *type; + + list_for_each_entry(type, &_exception_store_types, list) + if (!strcmp(name, type->name)) + return type; + + return NULL; +} + +static struct dm_exception_store_type *_get_exception_store_type(const char *name) +{ + struct dm_exception_store_type *type; + + spin_lock(&_lock); + + type = __find_exception_store_type(name); + + if (type && !try_module_get(type->module)) + type = NULL; + + spin_unlock(&_lock); + + return type; +} + +/* + * get_type + * @type_name + * + * Attempt to retrieve the dm_exception_store_type by name. If not already + * available, attempt to load the appropriate module. + * + * Exstore modules are named "dm-exstore-" followed by the 'type_name'. + * Modules may contain multiple types. + * This function will first try the module "dm-exstore-<type_name>", + * then truncate 'type_name' on the last '-' and try again. + * + * For example, if type_name was "clustered-shared", it would search + * 'dm-exstore-clustered-shared' then 'dm-exstore-clustered'. + * + * 'dm-exception-store-<type_name>' is too long of a name in my + * opinion, which is why I've chosen to have the files + * containing exception store implementations be 'dm-exstore-<type_name>'. + * If you want your module to be autoloaded, you will follow this + * naming convention. + * + * Returns: dm_exception_store_type* on success, NULL on failure + */ +static struct dm_exception_store_type *get_type(const char *type_name) +{ + char *p, *type_name_dup; + struct dm_exception_store_type *type; + + type = _get_exception_store_type(type_name); + if (type) + return type; + + type_name_dup = kstrdup(type_name, GFP_KERNEL); + if (!type_name_dup) { + DMERR("No memory left to attempt load for \"%s\"", type_name); + return NULL; + } + + while (request_module("dm-exstore-%s", type_name_dup) || + !(type = _get_exception_store_type(type_name))) { + p = strrchr(type_name_dup, '-'); + if (!p) + break; + p[0] = '\0'; + } + + if (!type) + DMWARN("Module for exstore type \"%s\" not found.", type_name); + + kfree(type_name_dup); + + return type; +} + +static void put_type(struct dm_exception_store_type *type) +{ + spin_lock(&_lock); + module_put(type->module); + spin_unlock(&_lock); +} + +int dm_exception_store_type_register(struct dm_exception_store_type *type) +{ + int r = 0; + + spin_lock(&_lock); + if (!__find_exception_store_type(type->name)) + list_add(&type->list, &_exception_store_types); + else + r = -EEXIST; + spin_unlock(&_lock); + + return r; +} +EXPORT_SYMBOL(dm_exception_store_type_register); + +int dm_exception_store_type_unregister(struct dm_exception_store_type *type) +{ + spin_lock(&_lock); + + if (!__find_exception_store_type(type->name)) { + spin_unlock(&_lock); + return -EINVAL; + } + + list_del(&type->list); + + spin_unlock(&_lock); + + return 0; +} +EXPORT_SYMBOL(dm_exception_store_type_unregister); + +/* + * Round a number up to the nearest 'size' boundary. size must + * be a power of 2. + */ +static ulong round_up(ulong n, ulong size) +{ + size--; + return (n + size) & ~size; +} + +static int set_chunk_size(struct dm_exception_store *store, + const char *chunk_size_arg, char **error) +{ + unsigned long chunk_size_ulong; + char *value; + + chunk_size_ulong = simple_strtoul(chunk_size_arg, &value, 10); + if (*chunk_size_arg == '\0' || *value != '\0') { + *error = "Invalid chunk size"; + return -EINVAL; + } + + if (!chunk_size_ulong) { + store->chunk_size = store->chunk_mask = store->chunk_shift = 0; + return 0; + } + + /* + * Chunk size must be multiple of page size. Silently + * round up if it's not. + */ + chunk_size_ulong = round_up(chunk_size_ulong, PAGE_SIZE >> 9); + + /* Check chunk_size is a power of 2 */ + if (!is_power_of_2(chunk_size_ulong)) { + *error = "Chunk size is not a power of 2"; + return -EINVAL; + } + + /* Validate the chunk size against the device block size */ + if (chunk_size_ulong % (bdev_hardsect_size(store->cow->bdev) >> 9)) { + *error = "Chunk size is not a multiple of device blocksize"; + return -EINVAL; + } + + store->chunk_size = chunk_size_ulong; + store->chunk_mask = chunk_size_ulong - 1; + store->chunk_shift = ffs(chunk_size_ulong) - 1; + + return 0; +} + +int dm_exception_store_create(struct dm_target *ti, int argc, char **argv, + unsigned *args_used, + struct dm_exception_store **store) +{ + int r = 0; + struct dm_exception_store_type *type; + struct dm_exception_store *tmp_store; + char persistent; + + if (argc < 3) { + ti->error = "Insufficient exception store arguments"; + return -EINVAL; + } + + tmp_store = kmalloc(sizeof(*tmp_store), GFP_KERNEL); + if (!tmp_store) { + ti->error = "Exception store allocation failed"; + return -ENOMEM; + } + + persistent = toupper(*argv[1]); + if (persistent != 'P' && persistent != 'N') { + ti->error = "Persistent flag is not P or N"; + return -EINVAL; + } + + type = get_type(argv[1]); + if (!type) { + ti->error = "Exception store type not recognised"; + r = -EINVAL; + goto bad_type; + } + + tmp_store->type = type; + tmp_store->ti = ti; + + r = dm_get_device(ti, argv[0], 0, 0, + FMODE_READ | FMODE_WRITE, &tmp_store->cow); + if (r) { + ti->error = "Cannot get COW device"; + goto bad_cow; + } + + r = set_chunk_size(tmp_store, argv[2], &ti->error); + if (r) + goto bad_cow; + + r = type->ctr(tmp_store, 0, NULL); + if (r) { + ti->error = "Exception store type constructor failed"; + goto bad_ctr; + } + + *args_used = 3; + *store = tmp_store; + return 0; + +bad_ctr: + dm_put_device(ti, tmp_store->cow); +bad_cow: + put_type(type); +bad_type: + kfree(tmp_store); + return r; +} +EXPORT_SYMBOL(dm_exception_store_create); + +void dm_exception_store_destroy(struct dm_exception_store *store) +{ + store->type->dtr(store); + dm_put_device(store->ti, store->cow); + put_type(store->type); + kfree(store); +} +EXPORT_SYMBOL(dm_exception_store_destroy); + int dm_exception_store_init(void) { int r; diff --git a/drivers/md/dm-exception-store.h b/drivers/md/dm-exception-store.h index bb9f33d..0a2e6e7 100644 --- a/drivers/md/dm-exception-store.h +++ b/drivers/md/dm-exception-store.h @@ -37,11 +37,18 @@ struct dm_snap_exception { * Abstraction to handle the meta/layout of exception stores (the * COW device). */ -struct dm_exception_store { +struct dm_exception_store; +struct dm_exception_store_type { + const char *name; + struct module *module; + + int (*ctr) (struct dm_exception_store *store, + unsigned argc, char **argv); + /* * Destroys this object when you've finished with it. */ - void (*destroy) (struct dm_exception_store *store); + void (*dtr) (struct dm_exception_store *store); /* * The target shouldn't read the COW device until this is @@ -72,8 +79,9 @@ struct dm_exception_store { */ void (*drop_snapshot) (struct dm_exception_store *store); - int (*status) (struct dm_exception_store *store, status_type_t status, - char *result, unsigned int maxlen); + unsigned (*status) (struct dm_exception_store *store, + status_type_t status, char *result, + unsigned maxlen); /* * Return how full the snapshot is. @@ -82,7 +90,21 @@ struct dm_exception_store { sector_t *numerator, sector_t *denominator); - struct dm_snapshot *snap; + /* For internal device-mapper use only. */ + struct list_head list; +}; + +struct dm_exception_store { + struct dm_exception_store_type *type; + struct dm_target *ti; + + struct dm_dev *cow; + + /* Size of data blocks saved - must be a power of 2 */ + chunk_t chunk_size; + chunk_t chunk_mask; + chunk_t chunk_shift; + void *context; }; @@ -129,6 +151,28 @@ static inline void dm_consecutive_chunk_count_inc(struct dm_snap_exception *e) # endif +/* + * Return the number of sectors in the device. + */ +static inline sector_t get_dev_size(struct block_device *bdev) +{ + return bdev->bd_inode->i_size >> SECTOR_SHIFT; +} + +static inline chunk_t sector_to_chunk(struct dm_exception_store *store, + sector_t sector) +{ + return (sector & ~store->chunk_mask) >> store->chunk_shift; +} + +int dm_exception_store_type_register(struct dm_exception_store_type *type); +int dm_exception_store_type_unregister(struct dm_exception_store_type *type); + +int dm_exception_store_create(struct dm_target *ti, int argc, char **argv, + unsigned *args_used, + struct dm_exception_store **store); +void dm_exception_store_destroy(struct dm_exception_store *store); + int dm_exception_store_init(void); void dm_exception_store_exit(void); @@ -141,8 +185,4 @@ void dm_persistent_snapshot_exit(void); int dm_transient_snapshot_init(void); void dm_transient_snapshot_exit(void); -int dm_create_persistent(struct dm_exception_store *store); - -int dm_create_transient(struct dm_exception_store *store); - #endif /* _LINUX_DM_EXCEPTION_STORE */ diff --git a/drivers/md/dm-io.c b/drivers/md/dm-io.c index 36e2b5e..e73aabd 100644 --- a/drivers/md/dm-io.c +++ b/drivers/md/dm-io.c @@ -370,16 +370,13 @@ static int sync_io(struct dm_io_client *client, unsigned int num_regions, while (1) { set_current_state(TASK_UNINTERRUPTIBLE); - if (!atomic_read(&io.count) || signal_pending(current)) + if (!atomic_read(&io.count)) break; io_schedule(); } set_current_state(TASK_RUNNING); - if (atomic_read(&io.count)) - return -EINTR; - if (error_bits) *error_bits = io.error_bits; diff --git a/drivers/md/dm-log.c b/drivers/md/dm-log.c index 737961f..be233bc 100644 --- a/drivers/md/dm-log.c +++ b/drivers/md/dm-log.c @@ -16,40 +16,29 @@ #define DM_MSG_PREFIX "dirty region log" -struct dm_dirty_log_internal { - struct dm_dirty_log_type *type; - - struct list_head list; - long use; -}; - static LIST_HEAD(_log_types); static DEFINE_SPINLOCK(_lock); -static struct dm_dirty_log_internal *__find_dirty_log_type(const char *name) +static struct dm_dirty_log_type *__find_dirty_log_type(const char *name) { - struct dm_dirty_log_internal *log_type; + struct dm_dirty_log_type *log_type; list_for_each_entry(log_type, &_log_types, list) - if (!strcmp(name, log_type->type->name)) + if (!strcmp(name, log_type->name)) return log_type; return NULL; } -static struct dm_dirty_log_internal *_get_dirty_log_type(const char *name) +static struct dm_dirty_log_type *_get_dirty_log_type(const char *name) { - struct dm_dirty_log_internal *log_type; + struct dm_dirty_log_type *log_type; spin_lock(&_lock); log_type = __find_dirty_log_type(name); - if (log_type) { - if (!log_type->use && !try_module_get(log_type->type->module)) - log_type = NULL; - else - log_type->use++; - } + if (log_type && !try_module_get(log_type->module)) + log_type = NULL; spin_unlock(&_lock); @@ -76,14 +65,14 @@ static struct dm_dirty_log_internal *_get_dirty_log_type(const char *name) static struct dm_dirty_log_type *get_type(const char *type_name) { char *p, *type_name_dup; - struct dm_dirty_log_internal *log_type; + struct dm_dirty_log_type *log_type; if (!type_name) return NULL; log_type = _get_dirty_log_type(type_name); if (log_type) - return log_type->type; + return log_type; type_name_dup = kstrdup(type_name, GFP_KERNEL); if (!type_name_dup) { @@ -105,56 +94,33 @@ static struct dm_dirty_log_type *get_type(const char *type_name) kfree(type_name_dup); - return log_type ? log_type->type : NULL; + return log_type; } static void put_type(struct dm_dirty_log_type *type) { - struct dm_dirty_log_internal *log_type; - if (!type) return; spin_lock(&_lock); - log_type = __find_dirty_log_type(type->name); - if (!log_type) + if (!__find_dirty_log_type(type->name)) goto out; - if (!--log_type->use) - module_put(type->module); - - BUG_ON(log_type->use < 0); + module_put(type->module); out: spin_unlock(&_lock); } -static struct dm_dirty_log_internal *_alloc_dirty_log_type(struct dm_dirty_log_type *type) -{ - struct dm_dirty_log_internal *log_type = kzalloc(sizeof(*log_type), - GFP_KERNEL); - - if (log_type) - log_type->type = type; - - return log_type; -} - int dm_dirty_log_type_register(struct dm_dirty_log_type *type) { - struct dm_dirty_log_internal *log_type = _alloc_dirty_log_type(type); int r = 0; - if (!log_type) - return -ENOMEM; - spin_lock(&_lock); if (!__find_dirty_log_type(type->name)) - list_add(&log_type->list, &_log_types); - else { - kfree(log_type); + list_add(&type->list, &_log_types); + else r = -EEXIST; - } spin_unlock(&_lock); return r; @@ -163,25 +129,16 @@ EXPORT_SYMBOL(dm_dirty_log_type_register); int dm_dirty_log_type_unregister(struct dm_dirty_log_type *type) { - struct dm_dirty_log_internal *log_type; - spin_lock(&_lock); - log_type = __find_dirty_log_type(type->name); - if (!log_type) { + if (!__find_dirty_log_type(type->name)) { spin_unlock(&_lock); return -EINVAL; } - if (log_type->use) { - spin_unlock(&_lock); - return -ETXTBSY; - } - - list_del(&log_type->list); + list_del(&type->list); spin_unlock(&_lock); - kfree(log_type); return 0; } diff --git a/drivers/md/dm-path-selector.c b/drivers/md/dm-path-selector.c index 96ea226..42c04f0 100644 --- a/drivers/md/dm-path-selector.c +++ b/drivers/md/dm-path-selector.c @@ -17,9 +17,7 @@ struct ps_internal { struct path_selector_type pst; - struct list_head list; - long use; }; #define pst_to_psi(__pst) container_of((__pst), struct ps_internal, pst) @@ -45,12 +43,8 @@ static struct ps_internal *get_path_selector(const char *name) down_read(&_ps_lock); psi = __find_path_selector_type(name); - if (psi) { - if ((psi->use == 0) && !try_module_get(psi->pst.module)) - psi = NULL; - else - psi->use++; - } + if (psi && !try_module_get(psi->pst.module)) + psi = NULL; up_read(&_ps_lock); return psi; @@ -84,11 +78,7 @@ void dm_put_path_selector(struct path_selector_type *pst) if (!psi) goto out; - if (--psi->use == 0) - module_put(psi->pst.module); - - BUG_ON(psi->use < 0); - + module_put(psi->pst.module); out: up_read(&_ps_lock); } @@ -136,11 +126,6 @@ int dm_unregister_path_selector(struct path_selector_type *pst) return -EINVAL; } - if (psi->use) { - up_write(&_ps_lock); - return -ETXTBSY; - } - list_del(&psi->list); up_write(&_ps_lock); diff --git a/drivers/md/dm-raid1.c b/drivers/md/dm-raid1.c index 4d6bc10..536ef0b 100644 --- a/drivers/md/dm-raid1.c +++ b/drivers/md/dm-raid1.c @@ -145,6 +145,8 @@ struct dm_raid1_read_record { struct dm_bio_details details; }; +static struct kmem_cache *_dm_raid1_read_record_cache; + /* * Every mirror should look like this one. */ @@ -586,6 +588,9 @@ static void do_writes(struct mirror_set *ms, struct bio_list *writes) int state; struct bio *bio; struct bio_list sync, nosync, recover, *this_list = NULL; + struct bio_list requeue; + struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh); + region_t region; if (!writes->head) return; @@ -596,10 +601,18 @@ static void do_writes(struct mirror_set *ms, struct bio_list *writes) bio_list_init(&sync); bio_list_init(&nosync); bio_list_init(&recover); + bio_list_init(&requeue); while ((bio = bio_list_pop(writes))) { - state = dm_rh_get_state(ms->rh, - dm_rh_bio_to_region(ms->rh, bio), 1); + region = dm_rh_bio_to_region(ms->rh, bio); + + if (log->type->is_remote_recovering && + log->type->is_remote_recovering(log, region)) { + bio_list_add(&requeue, bio); + continue; + } + + state = dm_rh_get_state(ms->rh, region, 1); switch (state) { case DM_RH_CLEAN: case DM_RH_DIRTY: @@ -619,6 +632,16 @@ static void do_writes(struct mirror_set *ms, struct bio_list *writes) } /* + * Add bios that are delayed due to remote recovery + * back on to the write queue + */ + if (unlikely(requeue.head)) { + spin_lock_irq(&ms->lock); + bio_list_merge(&ms->writes, &requeue); + spin_unlock_irq(&ms->lock); + } + + /* * Increment the pending counts for any regions that will * be written to (writes to recover regions are going to * be delayed). @@ -764,9 +787,9 @@ static struct mirror_set *alloc_context(unsigned int nr_mirrors, atomic_set(&ms->suspend, 0); atomic_set(&ms->default_mirror, DEFAULT_MIRROR); - len = sizeof(struct dm_raid1_read_record); - ms->read_record_pool = mempool_create_kmalloc_pool(MIN_READ_RECORDS, - len); + ms->read_record_pool = mempool_create_slab_pool(MIN_READ_RECORDS, + _dm_raid1_read_record_cache); + if (!ms->read_record_pool) { ti->error = "Error creating mirror read_record_pool"; kfree(ms); @@ -1279,16 +1302,31 @@ static int __init dm_mirror_init(void) { int r; + _dm_raid1_read_record_cache = KMEM_CACHE(dm_raid1_read_record, 0); + if (!_dm_raid1_read_record_cache) { + DMERR("Can't allocate dm_raid1_read_record cache"); + r = -ENOMEM; + goto bad_cache; + } + r = dm_register_target(&mirror_target); - if (r < 0) + if (r < 0) { DMERR("Failed to register mirror target"); + goto bad_target; + } + + return 0; +bad_target: + kmem_cache_destroy(_dm_raid1_read_record_cache); +bad_cache: return r; } static void __exit dm_mirror_exit(void) { dm_unregister_target(&mirror_target); + kmem_cache_destroy(_dm_raid1_read_record_cache); } /* Module hooks */ diff --git a/drivers/md/dm-snap-persistent.c b/drivers/md/dm-snap-persistent.c index 936b34e..e75c6dd 100644 --- a/drivers/md/dm-snap-persistent.c +++ b/drivers/md/dm-snap-persistent.c @@ -6,7 +6,6 @@ */ #include "dm-exception-store.h" -#include "dm-snap.h" #include <linux/mm.h> #include <linux/pagemap.h> @@ -89,7 +88,7 @@ struct commit_callback { * The top level structure for a persistent exception store. */ struct pstore { - struct dm_snapshot *snap; /* up pointer to my snapshot */ + struct dm_exception_store *store; int version; int valid; uint32_t exceptions_per_area; @@ -141,7 +140,7 @@ static int alloc_area(struct pstore *ps) int r = -ENOMEM; size_t len; - len = ps->snap->chunk_size << SECTOR_SHIFT; + len = ps->store->chunk_size << SECTOR_SHIFT; /* * Allocate the chunk_size block of memory that will hold @@ -163,9 +162,12 @@ static int alloc_area(struct pstore *ps) static void free_area(struct pstore *ps) { - vfree(ps->area); + if (ps->area) + vfree(ps->area); ps->area = NULL; - vfree(ps->zero_area); + + if (ps->zero_area) + vfree(ps->zero_area); ps->zero_area = NULL; } @@ -189,9 +191,9 @@ static void do_metadata(struct work_struct *work) static int chunk_io(struct pstore *ps, chunk_t chunk, int rw, int metadata) { struct dm_io_region where = { - .bdev = ps->snap->cow->bdev, - .sector = ps->snap->chunk_size * chunk, - .count = ps->snap->chunk_size, + .bdev = ps->store->cow->bdev, + .sector = ps->store->chunk_size * chunk, + .count = ps->store->chunk_size, }; struct dm_io_request io_req = { .bi_rw = rw, @@ -247,15 +249,15 @@ static int area_io(struct pstore *ps, int rw) static void zero_memory_area(struct pstore *ps) { - memset(ps->area, 0, ps->snap->chunk_size << SECTOR_SHIFT); + memset(ps->area, 0, ps->store->chunk_size << SECTOR_SHIFT); } static int zero_disk_area(struct pstore *ps, chunk_t area) { struct dm_io_region where = { - .bdev = ps->snap->cow->bdev, - .sector = ps->snap->chunk_size * area_location(ps, area), - .count = ps->snap->chunk_size, + .bdev = ps->store->cow->bdev, + .sector = ps->store->chunk_size * area_location(ps, area), + .count = ps->store->chunk_size, }; struct dm_io_request io_req = { .bi_rw = WRITE, @@ -278,15 +280,15 @@ static int read_header(struct pstore *ps, int *new_snapshot) /* * Use default chunk size (or hardsect_size, if larger) if none supplied */ - if (!ps->snap->chunk_size) { - ps->snap->chunk_size = max(DM_CHUNK_SIZE_DEFAULT_SECTORS, - bdev_hardsect_size(ps->snap->cow->bdev) >> 9); - ps->snap->chunk_mask = ps->snap->chunk_size - 1; - ps->snap->chunk_shift = ffs(ps->snap->chunk_size) - 1; + if (!ps->store->chunk_size) { + ps->store->chunk_size = max(DM_CHUNK_SIZE_DEFAULT_SECTORS, + bdev_hardsect_size(ps->store->cow->bdev) >> 9); + ps->store->chunk_mask = ps->store->chunk_size - 1; + ps->store->chunk_shift = ffs(ps->store->chunk_size) - 1; chunk_size_supplied = 0; } - ps->io_client = dm_io_client_create(sectors_to_pages(ps->snap-> + ps->io_client = dm_io_client_create(sectors_to_pages(ps->store-> chunk_size)); if (IS_ERR(ps->io_client)) return PTR_ERR(ps->io_client); @@ -317,22 +319,22 @@ static int read_header(struct pstore *ps, int *new_snapshot) ps->version = le32_to_cpu(dh->version); chunk_size = le32_to_cpu(dh->chunk_size); - if (!chunk_size_supplied || ps->snap->chunk_size == chunk_size) + if (!chunk_size_supplied || ps->store->chunk_size == chunk_size) return 0; DMWARN("chunk size %llu in device metadata overrides " "table chunk size of %llu.", (unsigned long long)chunk_size, - (unsigned long long)ps->snap->chunk_size); + (unsigned long long)ps->store->chunk_size); /* We had a bogus chunk_size. Fix stuff up. */ free_area(ps); - ps->snap->chunk_size = chunk_size; - ps->snap->chunk_mask = chunk_size - 1; - ps->snap->chunk_shift = ffs(chunk_size) - 1; + ps->store->chunk_size = chunk_size; + ps->store->chunk_mask = chunk_size - 1; + ps->store->chunk_shift = ffs(chunk_size) - 1; - r = dm_io_client_resize(sectors_to_pages(ps->snap->chunk_size), + r = dm_io_client_resize(sectors_to_pages(ps->store->chunk_size), ps->io_client); if (r) return r; @@ -349,13 +351,13 @@ static int write_header(struct pstore *ps) { struct disk_header *dh; - memset(ps->area, 0, ps->snap->chunk_size << SECTOR_SHIFT); + memset(ps->area, 0, ps->store->chunk_size << SECTOR_SHIFT); dh = (struct disk_header *) ps->area; dh->magic = cpu_to_le32(SNAP_MAGIC); dh->valid = cpu_to_le32(ps->valid); dh->version = cpu_to_le32(ps->version); - dh->chunk_size = cpu_to_le32(ps->snap->chunk_size); + dh->chunk_size = cpu_to_le32(ps->store->chunk_size); return chunk_io(ps, 0, WRITE, 1); } @@ -474,18 +476,25 @@ static struct pstore *get_info(struct dm_exception_store *store) static void persistent_fraction_full(struct dm_exception_store *store, sector_t *numerator, sector_t *denominator) { - *numerator = get_info(store)->next_free * store->snap->chunk_size; - *denominator = get_dev_size(store->snap->cow->bdev); + *numerator = get_info(store)->next_free * store->chunk_size; + *denominator = get_dev_size(store->cow->bdev); } -static void persistent_destroy(struct dm_exception_store *store) +static void persistent_dtr(struct dm_exception_store *store) { struct pstore *ps = get_info(store); destroy_workqueue(ps->metadata_wq); - dm_io_client_destroy(ps->io_client); - vfree(ps->callbacks); + + /* Created in read_header */ + if (ps->io_client) + dm_io_client_destroy(ps->io_client); free_area(ps); + + /* Allocated in persistent_read_metadata */ + if (ps->callbacks) + vfree(ps->callbacks); + kfree(ps); } @@ -507,7 +516,7 @@ static int persistent_read_metadata(struct dm_exception_store *store, /* * Now we know correct chunk_size, complete the initialisation. */ - ps->exceptions_per_area = (ps->snap->chunk_size << SECTOR_SHIFT) / + ps->exceptions_per_area = (ps->store->chunk_size << SECTOR_SHIFT) / sizeof(struct disk_exception); ps->callbacks = dm_vcalloc(ps->exceptions_per_area, sizeof(*ps->callbacks)); @@ -564,10 +573,10 @@ static int persistent_prepare_exception(struct dm_exception_store *store, struct pstore *ps = get_info(store); uint32_t stride; chunk_t next_free; - sector_t size = get_dev_size(store->snap->cow->bdev); + sector_t size = get_dev_size(store->cow->bdev); /* Is there enough room ? */ - if (size < ((ps->next_free + 1) * store->snap->chunk_size)) + if (size < ((ps->next_free + 1) * store->chunk_size)) return -ENOSPC; e->new_chunk = ps->next_free; @@ -656,16 +665,17 @@ static void persistent_drop_snapshot(struct dm_exception_store *store) DMWARN("write header failed"); } -int dm_create_persistent(struct dm_exception_store *store) +static int persistent_ctr(struct dm_exception_store *store, + unsigned argc, char **argv) { struct pstore *ps; /* allocate the pstore */ - ps = kmalloc(sizeof(*ps), GFP_KERNEL); + ps = kzalloc(sizeof(*ps), GFP_KERNEL); if (!ps) return -ENOMEM; - ps->snap = store->snap; + ps->store = store; ps->valid = 1; ps->version = SNAPSHOT_DISK_VERSION; ps->area = NULL; @@ -683,22 +693,77 @@ int dm_create_persistent(struct dm_exception_store *store) return -ENOMEM; } - store->destroy = persistent_destroy; - store->read_metadata = persistent_read_metadata; - store->prepare_exception = persistent_prepare_exception; - store->commit_exception = persistent_commit_exception; - store->drop_snapshot = persistent_drop_snapshot; - store->fraction_full = persistent_fraction_full; store->context = ps; return 0; } +static unsigned persistent_status(struct dm_exception_store *store, + status_type_t status, char *result, + unsigned maxlen) +{ + unsigned sz = 0; + + switch (status) { + case STATUSTYPE_INFO: + break; + case STATUSTYPE_TABLE: + DMEMIT(" %s P %llu", store->cow->name, + (unsigned long long)store->chunk_size); + } + + return sz; +} + +static struct dm_exception_store_type _persistent_type = { + .name = "persistent", + .module = THIS_MODULE, + .ctr = persistent_ctr, + .dtr = persistent_dtr, + .read_metadata = persistent_read_metadata, + .prepare_exception = persistent_prepare_exception, + .commit_exception = persistent_commit_exception, + .drop_snapshot = persistent_drop_snapshot, + .fraction_full = persistent_fraction_full, + .status = persistent_status, +}; + +static struct dm_exception_store_type _persistent_compat_type = { + .name = "P", + .module = THIS_MODULE, + .ctr = persistent_ctr, + .dtr = persistent_dtr, + .read_metadata = persistent_read_metadata, + .prepare_exception = persistent_prepare_exception, + .commit_exception = persistent_commit_exception, + .drop_snapshot = persistent_drop_snapshot, + .fraction_full = persistent_fraction_full, + .status = persistent_status, +}; + int dm_persistent_snapshot_init(void) { - return 0; + int r; + + r = dm_exception_store_type_register(&_persistent_type); + if (r) { + DMERR("Unable to register persistent exception store type"); + return r; + } + + r = dm_exception_store_type_register(&_persistent_compat_type); + if (r) { + DMERR("Unable to register old-style persistent exception " + "store type"); + dm_exception_store_type_unregister(&_persistent_type); + return r; + } + + return r; } void dm_persistent_snapshot_exit(void) { + dm_exception_store_type_unregister(&_persistent_type); + dm_exception_store_type_unregister(&_persistent_compat_type); } diff --git a/drivers/md/dm-snap-transient.c b/drivers/md/dm-snap-transient.c index 7f6e2e6..cde5aa5 100644 --- a/drivers/md/dm-snap-transient.c +++ b/drivers/md/dm-snap-transient.c @@ -6,7 +6,6 @@ */ #include "dm-exception-store.h" -#include "dm-snap.h" #include <linux/mm.h> #include <linux/pagemap.h> @@ -23,7 +22,7 @@ struct transient_c { sector_t next_free; }; -static void transient_destroy(struct dm_exception_store *store) +static void transient_dtr(struct dm_exception_store *store) { kfree(store->context); } @@ -39,14 +38,14 @@ static int transient_read_metadata(struct dm_exception_store *store, static int transient_prepare_exception(struct dm_exception_store *store, struct dm_snap_exception *e) { - struct transient_c *tc = (struct transient_c *) store->context; - sector_t size = get_dev_size(store->snap->cow->bdev); + struct transient_c *tc = store->context; + sector_t size = get_dev_size(store->cow->bdev); - if (size < (tc->next_free + store->snap->chunk_size)) + if (size < (tc->next_free + store->chunk_size)) return -1; - e->new_chunk = sector_to_chunk(store->snap, tc->next_free); - tc->next_free += store->snap->chunk_size; + e->new_chunk = sector_to_chunk(store, tc->next_free); + tc->next_free += store->chunk_size; return 0; } @@ -64,20 +63,14 @@ static void transient_fraction_full(struct dm_exception_store *store, sector_t *numerator, sector_t *denominator) { *numerator = ((struct transient_c *) store->context)->next_free; - *denominator = get_dev_size(store->snap->cow->bdev); + *denominator = get_dev_size(store->cow->bdev); } -int dm_create_transient(struct dm_exception_store *store) +static int transient_ctr(struct dm_exception_store *store, + unsigned argc, char **argv) { struct transient_c *tc; - store->destroy = transient_destroy; - store->read_metadata = transient_read_metadata; - store->prepare_exception = transient_prepare_exception; - store->commit_exception = transient_commit_exception; - store->drop_snapshot = NULL; - store->fraction_full = transient_fraction_full; - tc = kmalloc(sizeof(struct transient_c), GFP_KERNEL); if (!tc) return -ENOMEM; @@ -88,11 +81,70 @@ int dm_create_transient(struct dm_exception_store *store) return 0; } +static unsigned transient_status(struct dm_exception_store *store, + status_type_t status, char *result, + unsigned maxlen) +{ + unsigned sz = 0; + + switch (status) { + case STATUSTYPE_INFO: + break; + case STATUSTYPE_TABLE: + DMEMIT(" %s N %llu", store->cow->name, + (unsigned long long)store->chunk_size); + } + + return sz; +} + +static struct dm_exception_store_type _transient_type = { + .name = "transient", + .module = THIS_MODULE, + .ctr = transient_ctr, + .dtr = transient_dtr, + .read_metadata = transient_read_metadata, + .prepare_exception = transient_prepare_exception, + .commit_exception = transient_commit_exception, + .fraction_full = transient_fraction_full, + .status = transient_status, +}; + +static struct dm_exception_store_type _transient_compat_type = { + .name = "N", + .module = THIS_MODULE, + .ctr = transient_ctr, + .dtr = transient_dtr, + .read_metadata = transient_read_metadata, + .prepare_exception = transient_prepare_exception, + .commit_exception = transient_commit_exception, + .fraction_full = transient_fraction_full, + .status = transient_status, +}; + int dm_transient_snapshot_init(void) { - return 0; + int r; + + r = dm_exception_store_type_register(&_transient_type); + if (r) { + DMWARN("Unable to register transient exception store type"); + return r; + } + + r = dm_exception_store_type_register(&_transient_compat_type); + if (r) { + DMWARN("Unable to register old-style transient " + "exception store type"); + dm_exception_store_type_unregister(&_transient_type); + return r; + } + + return r; } void dm_transient_snapshot_exit(void) { + dm_exception_store_type_unregister(&_transient_type); + dm_exception_store_type_unregister(&_transient_compat_type); } diff --git a/drivers/md/dm-snap.c b/drivers/md/dm-snap.c index 65ff82f..981a041 100644 --- a/drivers/md/dm-snap.c +++ b/drivers/md/dm-snap.c @@ -7,7 +7,6 @@ */ #include <linux/blkdev.h> -#include <linux/ctype.h> #include <linux/device-mapper.h> #include <linux/delay.h> #include <linux/fs.h> @@ -20,9 +19,9 @@ #include <linux/vmalloc.h> #include <linux/log2.h> #include <linux/dm-kcopyd.h> +#include <linux/workqueue.h> #include "dm-exception-store.h" -#include "dm-snap.h" #include "dm-bio-list.h" #define DM_MSG_PREFIX "snapshots" @@ -47,9 +46,76 @@ */ #define MIN_IOS 256 +#define DM_TRACKED_CHUNK_HASH_SIZE 16 +#define DM_TRACKED_CHUNK_HASH(x) ((unsigned long)(x) & \ + (DM_TRACKED_CHUNK_HASH_SIZE - 1)) + +struct exception_table { + uint32_t hash_mask; + unsigned hash_shift; + struct list_head *table; +}; + +struct dm_snapshot { + struct rw_semaphore lock; + + struct dm_dev *origin; + + /* List of snapshots per Origin */ + struct list_head list; + + /* You can't use a snapshot if this is 0 (e.g. if full) */ + int valid; + + /* Origin writes don't trigger exceptions until this is set */ + int active; + + mempool_t *pending_pool; + + atomic_t pending_exceptions_count; + + struct exception_table pending; + struct exception_table complete; + + /* + * pe_lock protects all pending_exception operations and access + * as well as the snapshot_bios list. + */ + spinlock_t pe_lock; + + /* The on disk metadata handler */ + struct dm_exception_store *store; + + struct dm_kcopyd_client *kcopyd_client; + + /* Queue of snapshot writes for ksnapd to flush */ + struct bio_list queued_bios; + struct work_struct queued_bios_work; + + /* Chunks with outstanding reads */ + mempool_t *tracked_chunk_pool; + spinlock_t tracked_chunk_lock; + struct hlist_head tracked_chunk_hash[DM_TRACKED_CHUNK_HASH_SIZE]; +}; + static struct workqueue_struct *ksnapd; static void flush_queued_bios(struct work_struct *work); +static sector_t chunk_to_sector(struct dm_exception_store *store, + chunk_t chunk) +{ + return chunk << store->chunk_shift; +} + +static int bdev_equal(struct block_device *lhs, struct block_device *rhs) +{ + /* + * There is only ever one instance of a particular block + * device so we can compare pointers safely. + */ + return lhs == rhs; +} + struct dm_snap_pending_exception { struct dm_snap_exception e; @@ -476,11 +542,11 @@ static int init_hash_tables(struct dm_snapshot *s) * Calculate based on the size of the original volume or * the COW volume... */ - cow_dev_size = get_dev_size(s->cow->bdev); + cow_dev_size = get_dev_size(s->store->cow->bdev); origin_dev_size = get_dev_size(s->origin->bdev); max_buckets = calc_max_buckets(); - hash_size = min(origin_dev_size, cow_dev_size) >> s->chunk_shift; + hash_size = min(origin_dev_size, cow_dev_size) >> s->store->chunk_shift; hash_size = min(hash_size, max_buckets); hash_size = rounddown_pow_of_two(hash_size); @@ -505,58 +571,6 @@ static int init_hash_tables(struct dm_snapshot *s) } /* - * Round a number up to the nearest 'size' boundary. size must - * be a power of 2. - */ -static ulong round_up(ulong n, ulong size) -{ - size--; - return (n + size) & ~size; -} - -static int set_chunk_size(struct dm_snapshot *s, const char *chunk_size_arg, - char **error) -{ - unsigned long chunk_size; - char *value; - - chunk_size = simple_strtoul(chunk_size_arg, &value, 10); - if (*chunk_size_arg == '\0' || *value != '\0') { - *error = "Invalid chunk size"; - return -EINVAL; - } - - if (!chunk_size) { - s->chunk_size = s->chunk_mask = s->chunk_shift = 0; - return 0; - } - - /* - * Chunk size must be multiple of page size. Silently - * round up if it's not. - */ - chunk_size = round_up(chunk_size, PAGE_SIZE >> 9); - - /* Check chunk_size is a power of 2 */ - if (!is_power_of_2(chunk_size)) { - *error = "Chunk size is not a power of 2"; - return -EINVAL; - } - - /* Validate the chunk size against the device block size */ - if (chunk_size % (bdev_hardsect_size(s->cow->bdev) >> 9)) { - *error = "Chunk size is not a multiple of device blocksize"; - return -EINVAL; - } - - s->chunk_size = chunk_size; - s->chunk_mask = chunk_size - 1; - s->chunk_shift = ffs(chunk_size) - 1; - - return 0; -} - -/* * Construct a snapshot mapping: <origin_dev> <COW-dev> <p/n> <chunk-size> */ static int snapshot_ctr(struct dm_target *ti, unsigned int argc, char **argv) @@ -564,91 +578,68 @@ static int snapshot_ctr(struct dm_target *ti, unsigned int argc, char **argv) struct dm_snapshot *s; int i; int r = -EINVAL; - char persistent; char *origin_path; - char *cow_path; + struct dm_exception_store *store; + unsigned args_used; if (argc != 4) { ti->error = "requires exactly 4 arguments"; r = -EINVAL; - goto bad1; + goto bad_args; } origin_path = argv[0]; - cow_path = argv[1]; - persistent = toupper(*argv[2]); + argv++; + argc--; - if (persistent != 'P' && persistent != 'N') { - ti->error = "Persistent flag is not P or N"; + r = dm_exception_store_create(ti, argc, argv, &args_used, &store); + if (r) { + ti->error = "Couldn't create exception store"; r = -EINVAL; - goto bad1; + goto bad_args; } + argv += args_used; + argc -= args_used; + s = kmalloc(sizeof(*s), GFP_KERNEL); - if (s == NULL) { + if (!s) { ti->error = "Cannot allocate snapshot context private " "structure"; r = -ENOMEM; - goto bad1; + goto bad_snap; } r = dm_get_device(ti, origin_path, 0, ti->len, FMODE_READ, &s->origin); if (r) { ti->error = "Cannot get origin device"; - goto bad2; - } - - r = dm_get_device(ti, cow_path, 0, 0, - FMODE_READ | FMODE_WRITE, &s->cow); - if (r) { - dm_put_device(ti, s->origin); - ti->error = "Cannot get COW device"; - goto bad2; + goto bad_origin; } - r = set_chunk_size(s, argv[3], &ti->error); - if (r) - goto bad3; - - s->type = persistent; - + s->store = store; s->valid = 1; s->active = 0; atomic_set(&s->pending_exceptions_count, 0); init_rwsem(&s->lock); spin_lock_init(&s->pe_lock); - s->ti = ti; /* Allocate hash table for COW data */ if (init_hash_tables(s)) { ti->error = "Unable to allocate hash table space"; r = -ENOMEM; - goto bad3; - } - - s->store.snap = s; - - if (persistent == 'P') - r = dm_create_persistent(&s->store); - else - r = dm_create_transient(&s->store); - - if (r) { - ti->error = "Couldn't create exception store"; - r = -EINVAL; - goto bad4; + goto bad_hash_tables; } r = dm_kcopyd_client_create(SNAPSHOT_PAGES, &s->kcopyd_client); if (r) { ti->error = "Could not create kcopyd client"; - goto bad5; + goto bad_kcopyd; } s->pending_pool = mempool_create_slab_pool(MIN_IOS, pending_cache); if (!s->pending_pool) { ti->error = "Could not allocate mempool for pending exceptions"; - goto bad6; + goto bad_pending_pool; } s->tracked_chunk_pool = mempool_create_slab_pool(MIN_IOS, @@ -665,7 +656,8 @@ static int snapshot_ctr(struct dm_target *ti, unsigned int argc, char **argv) spin_lock_init(&s->tracked_chunk_lock); /* Metadata must only be loaded into one table at once */ - r = s->store.read_metadata(&s->store, dm_add_exception, (void *)s); + r = s->store->type->read_metadata(s->store, dm_add_exception, + (void *)s); if (r < 0) { ti->error = "Failed to read snapshot metadata"; goto bad_load_and_register; @@ -686,34 +678,33 @@ static int snapshot_ctr(struct dm_target *ti, unsigned int argc, char **argv) } ti->private = s; - ti->split_io = s->chunk_size; + ti->split_io = s->store->chunk_size; return 0; - bad_load_and_register: +bad_load_and_register: mempool_destroy(s->tracked_chunk_pool); - bad_tracked_chunk_pool: +bad_tracked_chunk_pool: mempool_destroy(s->pending_pool); - bad6: +bad_pending_pool: dm_kcopyd_client_destroy(s->kcopyd_client); - bad5: - s->store.destroy(&s->store); - - bad4: +bad_kcopyd: exit_exception_table(&s->pending, pending_cache); exit_exception_table(&s->complete, exception_cache); - bad3: - dm_put_device(ti, s->cow); +bad_hash_tables: dm_put_device(ti, s->origin); - bad2: +bad_origin: kfree(s); - bad1: +bad_snap: + dm_exception_store_destroy(store); + +bad_args: return r; } @@ -724,8 +715,6 @@ static void __free_exceptions(struct dm_snapshot *s) exit_exception_table(&s->pending, pending_cache); exit_exception_table(&s->complete, exception_cache); - - s->store.destroy(&s->store); } static void snapshot_dtr(struct dm_target *ti) @@ -761,7 +750,8 @@ static void snapshot_dtr(struct dm_target *ti) mempool_destroy(s->pending_pool); dm_put_device(ti, s->origin); - dm_put_device(ti, s->cow); + + dm_exception_store_destroy(s->store); kfree(s); } @@ -820,12 +810,12 @@ static void __invalidate_snapshot(struct dm_snapshot *s, int err) else if (err == -ENOMEM) DMERR("Invalidating snapshot: Unable to allocate exception."); - if (s->store.drop_snapshot) - s->store.drop_snapshot(&s->store); + if (s->store->type->drop_snapshot) + s->store->type->drop_snapshot(s->store); s->valid = 0; - dm_table_event(s->ti->table); + dm_table_event(s->store->ti->table); } static void get_pending_exception(struct dm_snap_pending_exception *pe) @@ -943,8 +933,8 @@ static void copy_callback(int read_err, unsigned long write_err, void *context) else /* Update the metadata if we are persistent */ - s->store.commit_exception(&s->store, &pe->e, commit_callback, - pe); + s->store->type->commit_exception(s->store, &pe->e, + commit_callback, pe); } /* @@ -960,11 +950,11 @@ static void start_copy(struct dm_snap_pending_exception *pe) dev_size = get_dev_size(bdev); src.bdev = bdev; - src.sector = chunk_to_sector(s, pe->e.old_chunk); - src.count = min(s->chunk_size, dev_size - src.sector); + src.sector = chunk_to_sector(s->store, pe->e.old_chunk); + src.count = min(s->store->chunk_size, dev_size - src.sector); - dest.bdev = s->cow->bdev; - dest.sector = chunk_to_sector(s, pe->e.new_chunk); + dest.bdev = s->store->cow->bdev; + dest.sector = chunk_to_sector(s->store, pe->e.new_chunk); dest.count = src.count; /* Hand over to kcopyd */ @@ -972,6 +962,17 @@ static void start_copy(struct dm_snap_pending_exception *pe) &src, 1, &dest, 0, copy_callback, pe); } +static struct dm_snap_pending_exception * +__lookup_pending_exception(struct dm_snapshot *s, chunk_t chunk) +{ + struct dm_snap_exception *e = lookup_exception(&s->pending, chunk); + + if (!e) + return NULL; + + return container_of(e, struct dm_snap_pending_exception, e); +} + /* * Looks to see if this snapshot already has a pending exception * for this chunk, otherwise it allocates a new one and inserts @@ -981,40 +982,15 @@ static void start_copy(struct dm_snap_pending_exception *pe) * this. */ static struct dm_snap_pending_exception * -__find_pending_exception(struct dm_snapshot *s, struct bio *bio) +__find_pending_exception(struct dm_snapshot *s, + struct dm_snap_pending_exception *pe, chunk_t chunk) { - struct dm_snap_exception *e; - struct dm_snap_pending_exception *pe; - chunk_t chunk = sector_to_chunk(s, bio->bi_sector); + struct dm_snap_pending_exception *pe2; - /* - * Is there a pending exception for this already ? - */ - e = lookup_exception(&s->pending, chunk); - if (e) { - /* cast the exception to a pending exception */ - pe = container_of(e, struct dm_snap_pending_exception, e); - goto out; - } - - /* - * Create a new pending exception, we don't want - * to hold the lock while we do this. - */ - up_write(&s->lock); - pe = alloc_pending_exception(s); - down_write(&s->lock); - - if (!s->valid) { - free_pending_exception(pe); - return NULL; - } - - e = lookup_exception(&s->pending, chunk); - if (e) { + pe2 = __lookup_pending_exception(s, chunk); + if (pe2) { free_pending_exception(pe); - pe = container_of(e, struct dm_snap_pending_exception, e); - goto out; + return pe2; } pe->e.old_chunk = chunk; @@ -1024,7 +1000,7 @@ __find_pending_exception(struct dm_snapshot *s, struct bio *bio) atomic_set(&pe->ref_count, 0); pe->started = 0; - if (s->store.prepare_exception(&s->store, &pe->e)) { + if (s->store->type->prepare_exception(s->store, &pe->e)) { free_pending_exception(pe); return NULL; } @@ -1032,17 +1008,18 @@ __find_pending_exception(struct dm_snapshot *s, struct bio *bio) get_pending_exception(pe); insert_exception(&s->pending, &pe->e); - out: return pe; } static void remap_exception(struct dm_snapshot *s, struct dm_snap_exception *e, struct bio *bio, chunk_t chunk) { - bio->bi_bdev = s->cow->bdev; - bio->bi_sector = chunk_to_sector(s, dm_chunk_number(e->new_chunk) + - (chunk - e->old_chunk)) + - (bio->bi_sector & s->chunk_mask); + bio->bi_bdev = s->store->cow->bdev; + bio->bi_sector = chunk_to_sector(s->store, + dm_chunk_number(e->new_chunk) + + (chunk - e->old_chunk)) + + (bio->bi_sector & + s->store->chunk_mask); } static int snapshot_map(struct dm_target *ti, struct bio *bio, @@ -1054,7 +1031,7 @@ static int snapshot_map(struct dm_target *ti, struct bio *bio, chunk_t chunk; struct dm_snap_pending_exception *pe = NULL; - chunk = sector_to_chunk(s, bio->bi_sector); + chunk = sector_to_chunk(s->store, bio->bi_sector); /* Full snapshots are not usable */ /* To get here the table must be live so s->active is always set. */ @@ -1083,11 +1060,31 @@ static int snapshot_map(struct dm_target *ti, struct bio *bio, * writeable. */ if (bio_rw(bio) == WRITE) { - pe = __find_pending_exception(s, bio); + pe = __lookup_pending_exception(s, chunk); if (!pe) { - __invalidate_snapshot(s, -ENOMEM); - r = -EIO; - goto out_unlock; + up_write(&s->lock); + pe = alloc_pending_exception(s); + down_write(&s->lock); + + if (!s->valid) { + free_pending_exception(pe); + r = -EIO; + goto out_unlock; + } + + e = lookup_exception(&s->complete, chunk); + if (e) { + free_pending_exception(pe); + remap_exception(s, e, bio, chunk); + goto out_unlock; + } + + pe = __find_pending_exception(s, pe, chunk); + if (!pe) { + __invalidate_snapshot(s, -ENOMEM); + r = -EIO; + goto out_unlock; + } } remap_exception(s, &pe->e, bio, chunk); @@ -1137,24 +1134,25 @@ static void snapshot_resume(struct dm_target *ti) static int snapshot_status(struct dm_target *ti, status_type_t type, char *result, unsigned int maxlen) { + unsigned sz = 0; struct dm_snapshot *snap = ti->private; switch (type) { case STATUSTYPE_INFO: if (!snap->valid) - snprintf(result, maxlen, "Invalid"); + DMEMIT("Invalid"); else { - if (snap->store.fraction_full) { + if (snap->store->type->fraction_full) { sector_t numerator, denominator; - snap->store.fraction_full(&snap->store, - &numerator, - &denominator); - snprintf(result, maxlen, "%llu/%llu", - (unsigned long long)numerator, - (unsigned long long)denominator); + snap->store->type->fraction_full(snap->store, + &numerator, + &denominator); + DMEMIT("%llu/%llu", + (unsigned long long)numerator, + (unsigned long long)denominator); } else - snprintf(result, maxlen, "Unknown"); + DMEMIT("Unknown"); } break; @@ -1164,10 +1162,9 @@ static int snapshot_status(struct dm_target *ti, status_type_t type, * to make private copies if the output is to * make sense. */ - snprintf(result, maxlen, "%s %s %c %llu", - snap->origin->name, snap->cow->name, - snap->type, - (unsigned long long)snap->chunk_size); + DMEMIT("%s", snap->origin->name); + snap->store->type->status(snap->store, type, result + sz, + maxlen - sz); break; } @@ -1196,14 +1193,14 @@ static int __origin_write(struct list_head *snapshots, struct bio *bio) goto next_snapshot; /* Nothing to do if writing beyond end of snapshot */ - if (bio->bi_sector >= dm_table_get_size(snap->ti->table)) + if (bio->bi_sector >= dm_table_get_size(snap->store->ti->table)) goto next_snapshot; /* * Remember, different snapshots can have * different chunk sizes. */ - chunk = sector_to_chunk(snap, bio->bi_sector); + chunk = sector_to_chunk(snap->store, bio->bi_sector); /* * Check exception table to see if block @@ -1217,10 +1214,28 @@ static int __origin_write(struct list_head *snapshots, struct bio *bio) if (e) goto next_snapshot; - pe = __find_pending_exception(snap, bio); + pe = __lookup_pending_exception(snap, chunk); if (!pe) { - __invalidate_snapshot(snap, -ENOMEM); - goto next_snapshot; + up_write(&snap->lock); + pe = alloc_pending_exception(snap); + down_write(&snap->lock); + + if (!snap->valid) { + free_pending_exception(pe); + goto next_snapshot; + } + + e = lookup_exception(&snap->complete, chunk); + if (e) { + free_pending_exception(pe); + goto next_snapshot; + } + + pe = __find_pending_exception(snap, pe, chunk); + if (!pe) { + __invalidate_snapshot(snap, -ENOMEM); + goto next_snapshot; + } } if (!primary_pe) { @@ -1360,7 +1375,8 @@ static void origin_resume(struct dm_target *ti) o = __lookup_origin(dev->bdev); if (o) list_for_each_entry (snap, &o->snapshots, list) - chunk_size = min_not_zero(chunk_size, snap->chunk_size); + chunk_size = min_not_zero(chunk_size, + snap->store->chunk_size); up_read(&_origins_lock); ti->split_io = chunk_size; diff --git a/drivers/md/dm-snap.h b/drivers/md/dm-snap.h deleted file mode 100644 index d9e62b4..0000000 --- a/drivers/md/dm-snap.h +++ /dev/null @@ -1,105 +0,0 @@ -/* - * Copyright (C) 2001-2002 Sistina Software (UK) Limited. - * - * This file is released under the GPL. - */ - -#ifndef DM_SNAPSHOT_H -#define DM_SNAPSHOT_H - -#include <linux/device-mapper.h> -#include "dm-exception-store.h" -#include "dm-bio-list.h" -#include <linux/blkdev.h> -#include <linux/workqueue.h> - -struct exception_table { - uint32_t hash_mask; - unsigned hash_shift; - struct list_head *table; -}; - -#define DM_TRACKED_CHUNK_HASH_SIZE 16 -#define DM_TRACKED_CHUNK_HASH(x) ((unsigned long)(x) & \ - (DM_TRACKED_CHUNK_HASH_SIZE - 1)) - -struct dm_snapshot { - struct rw_semaphore lock; - struct dm_target *ti; - - struct dm_dev *origin; - struct dm_dev *cow; - - /* List of snapshots per Origin */ - struct list_head list; - - /* Size of data blocks saved - must be a power of 2 */ - chunk_t chunk_size; - chunk_t chunk_mask; - chunk_t chunk_shift; - - /* You can't use a snapshot if this is 0 (e.g. if full) */ - int valid; - - /* Origin writes don't trigger exceptions until this is set */ - int active; - - /* Used for display of table */ - char type; - - mempool_t *pending_pool; - - atomic_t pending_exceptions_count; - - struct exception_table pending; - struct exception_table complete; - - /* - * pe_lock protects all pending_exception operations and access - * as well as the snapshot_bios list. - */ - spinlock_t pe_lock; - - /* The on disk metadata handler */ - struct dm_exception_store store; - - struct dm_kcopyd_client *kcopyd_client; - - /* Queue of snapshot writes for ksnapd to flush */ - struct bio_list queued_bios; - struct work_struct queued_bios_work; - - /* Chunks with outstanding reads */ - mempool_t *tracked_chunk_pool; - spinlock_t tracked_chunk_lock; - struct hlist_head tracked_chunk_hash[DM_TRACKED_CHUNK_HASH_SIZE]; -}; - -/* - * Return the number of sectors in the device. - */ -static inline sector_t get_dev_size(struct block_device *bdev) -{ - return bdev->bd_inode->i_size >> SECTOR_SHIFT; -} - -static inline chunk_t sector_to_chunk(struct dm_snapshot *s, sector_t sector) -{ - return (sector & ~s->chunk_mask) >> s->chunk_shift; -} - -static inline sector_t chunk_to_sector(struct dm_snapshot *s, chunk_t chunk) -{ - return chunk << s->chunk_shift; -} - -static inline int bdev_equal(struct block_device *lhs, struct block_device *rhs) -{ - /* - * There is only ever one instance of a particular block - * device so we can compare pointers safely. - */ - return lhs == rhs; -} - -#endif diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c index 2fd66c3..e8361b1 100644 --- a/drivers/md/dm-table.c +++ b/drivers/md/dm-table.c @@ -399,28 +399,30 @@ static int check_device_area(struct dm_dev_internal *dd, sector_t start, } /* - * This upgrades the mode on an already open dm_dev. Being + * This upgrades the mode on an already open dm_dev, being * careful to leave things as they were if we fail to reopen the - * device. + * device and not to touch the existing bdev field in case + * it is accessed concurrently inside dm_table_any_congested(). */ static int upgrade_mode(struct dm_dev_internal *dd, fmode_t new_mode, struct mapped_device *md) { int r; - struct dm_dev_internal dd_copy; - dev_t dev = dd->dm_dev.bdev->bd_dev; + struct dm_dev_internal dd_new, dd_old; - dd_copy = *dd; + dd_new = dd_old = *dd; + + dd_new.dm_dev.mode |= new_mode; + dd_new.dm_dev.bdev = NULL; + + r = open_dev(&dd_new, dd->dm_dev.bdev->bd_dev, md); + if (r) + return r; dd->dm_dev.mode |= new_mode; - dd->dm_dev.bdev = NULL; - r = open_dev(dd, dev, md); - if (!r) - close_dev(&dd_copy, md); - else - *dd = dd_copy; + close_dev(&dd_old, md); - return r; + return 0; } /* diff --git a/drivers/md/dm-target.c b/drivers/md/dm-target.c index 7decf10..04feccf 100644 --- a/drivers/md/dm-target.c +++ b/drivers/md/dm-target.c @@ -14,45 +14,34 @@ #define DM_MSG_PREFIX "target" -struct tt_internal { - struct target_type tt; - - struct list_head list; - long use; -}; - static LIST_HEAD(_targets); static DECLARE_RWSEM(_lock); #define DM_MOD_NAME_SIZE 32 -static inline struct tt_internal *__find_target_type(const char *name) +static inline struct target_type *__find_target_type(const char *name) { - struct tt_internal *ti; + struct target_type *tt; - list_for_each_entry (ti, &_targets, list) - if (!strcmp(name, ti->tt.name)) - return ti; + list_for_each_entry(tt, &_targets, list) + if (!strcmp(name, tt->name)) + return tt; return NULL; } -static struct tt_internal *get_target_type(const char *name) +static struct target_type *get_target_type(const char *name) { - struct tt_internal *ti; + struct target_type *tt; down_read(&_lock); - ti = __find_target_type(name); - if (ti) { - if ((ti->use == 0) && !try_module_get(ti->tt.module)) - ti = NULL; - else - ti->use++; - } + tt = __find_target_type(name); + if (tt && !try_module_get(tt->module)) + tt = NULL; up_read(&_lock); - return ti; + return tt; } static void load_module(const char *name) @@ -62,92 +51,59 @@ static void load_module(const char *name) struct target_type *dm_get_target_type(const char *name) { - struct tt_internal *ti = get_target_type(name); + struct target_type *tt = get_target_type(name); - if (!ti) { + if (!tt) { load_module(name); - ti = get_target_type(name); + tt = get_target_type(name); } - return ti ? &ti->tt : NULL; + return tt; } -void dm_put_target_type(struct target_type *t) +void dm_put_target_type(struct target_type *tt) { - struct tt_internal *ti = (struct tt_internal *) t; - down_read(&_lock); - if (--ti->use == 0) - module_put(ti->tt.module); - - BUG_ON(ti->use < 0); + module_put(tt->module); up_read(&_lock); - - return; -} - -static struct tt_internal *alloc_target(struct target_type *t) -{ - struct tt_internal *ti = kzalloc(sizeof(*ti), GFP_KERNEL); - - if (ti) - ti->tt = *t; - - return ti; } - int dm_target_iterate(void (*iter_func)(struct target_type *tt, void *param), void *param) { - struct tt_internal *ti; + struct target_type *tt; down_read(&_lock); - list_for_each_entry (ti, &_targets, list) - iter_func(&ti->tt, param); + list_for_each_entry(tt, &_targets, list) + iter_func(tt, param); up_read(&_lock); return 0; } -int dm_register_target(struct target_type *t) +int dm_register_target(struct target_type *tt) { int rv = 0; - struct tt_internal *ti = alloc_target(t); - - if (!ti) - return -ENOMEM; down_write(&_lock); - if (__find_target_type(t->name)) + if (__find_target_type(tt->name)) rv = -EEXIST; else - list_add(&ti->list, &_targets); + list_add(&tt->list, &_targets); up_write(&_lock); - if (rv) - kfree(ti); return rv; } -void dm_unregister_target(struct target_type *t) +void dm_unregister_target(struct target_type *tt) { - struct tt_internal *ti; - down_write(&_lock); - if (!(ti = __find_target_type(t->name))) { - DMCRIT("Unregistering unrecognised target: %s", t->name); - BUG(); - } - - if (ti->use) { - DMCRIT("Attempt to unregister target still in use: %s", - t->name); + if (!__find_target_type(tt->name)) { + DMCRIT("Unregistering unrecognised target: %s", tt->name); BUG(); } - list_del(&ti->list); - kfree(ti); + list_del(&tt->list); up_write(&_lock); } @@ -156,17 +112,17 @@ void dm_unregister_target(struct target_type *t) * io-err: always fails an io, useful for bringing * up LVs that have holes in them. */ -static int io_err_ctr(struct dm_target *ti, unsigned int argc, char **args) +static int io_err_ctr(struct dm_target *tt, unsigned int argc, char **args) { return 0; } -static void io_err_dtr(struct dm_target *ti) +static void io_err_dtr(struct dm_target *tt) { /* empty */ } -static int io_err_map(struct dm_target *ti, struct bio *bio, +static int io_err_map(struct dm_target *tt, struct bio *bio, union map_info *map_context) { return -EIO; diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 8d40f27..788ba96 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -99,19 +99,9 @@ union map_info *dm_get_mapinfo(struct bio *bio) /* * Work processed by per-device workqueue. */ -struct dm_wq_req { - enum { - DM_WQ_FLUSH_DEFERRED, - } type; - struct work_struct work; - struct mapped_device *md; - void *context; -}; - struct mapped_device { struct rw_semaphore io_lock; struct mutex suspend_lock; - spinlock_t pushback_lock; rwlock_t map_lock; atomic_t holders; atomic_t open_count; @@ -129,8 +119,9 @@ struct mapped_device { */ atomic_t pending; wait_queue_head_t wait; + struct work_struct work; struct bio_list deferred; - struct bio_list pushback; + spinlock_t deferred_lock; /* * Processing queue (flush/barriers) @@ -453,7 +444,9 @@ static int queue_io(struct mapped_device *md, struct bio *bio) return 1; } + spin_lock_irq(&md->deferred_lock); bio_list_add(&md->deferred, bio); + spin_unlock_irq(&md->deferred_lock); up_write(&md->io_lock); return 0; /* deferred successfully */ @@ -537,16 +530,14 @@ static void dec_pending(struct dm_io *io, int error) if (io->error == DM_ENDIO_REQUEUE) { /* * Target requested pushing back the I/O. - * This must be handled before the sleeper on - * suspend queue merges the pushback list. */ - spin_lock_irqsave(&md->pushback_lock, flags); + spin_lock_irqsave(&md->deferred_lock, flags); if (__noflush_suspending(md)) - bio_list_add(&md->pushback, io->bio); + bio_list_add(&md->deferred, io->bio); else /* noflush suspend was interrupted. */ io->error = -EIO; - spin_unlock_irqrestore(&md->pushback_lock, flags); + spin_unlock_irqrestore(&md->deferred_lock, flags); } end_io_acct(io); @@ -834,20 +825,22 @@ static int __clone_and_map(struct clone_info *ci) } /* - * Split the bio into several clones. + * Split the bio into several clones and submit it to targets. */ -static int __split_bio(struct mapped_device *md, struct bio *bio) +static void __split_and_process_bio(struct mapped_device *md, struct bio *bio) { struct clone_info ci; int error = 0; ci.map = dm_get_table(md); - if (unlikely(!ci.map)) - return -EIO; + if (unlikely(!ci.map)) { + bio_io_error(bio); + return; + } if (unlikely(bio_barrier(bio) && !dm_table_barrier_ok(ci.map))) { dm_table_put(ci.map); bio_endio(bio, -EOPNOTSUPP); - return 0; + return; } ci.md = md; ci.bio = bio; @@ -867,8 +860,6 @@ static int __split_bio(struct mapped_device *md, struct bio *bio) /* drop the extra reference count */ dec_pending(ci.io, error); dm_table_put(ci.map); - - return 0; } /*----------------------------------------------------------------- * CRUD END @@ -959,8 +950,9 @@ static int dm_request(struct request_queue *q, struct bio *bio) down_read(&md->io_lock); } - r = __split_bio(md, bio); + __split_and_process_bio(md, bio); up_read(&md->io_lock); + return 0; out_req: if (r < 0) @@ -1074,6 +1066,8 @@ out: static struct block_device_operations dm_blk_dops; +static void dm_wq_work(struct work_struct *work); + /* * Allocate and initialise a blank device with a given minor. */ @@ -1101,7 +1095,7 @@ static struct mapped_device *alloc_dev(int minor) init_rwsem(&md->io_lock); mutex_init(&md->suspend_lock); - spin_lock_init(&md->pushback_lock); + spin_lock_init(&md->deferred_lock); rwlock_init(&md->map_lock); atomic_set(&md->holders, 1); atomic_set(&md->open_count, 0); @@ -1118,6 +1112,7 @@ static struct mapped_device *alloc_dev(int minor) md->queue->backing_dev_info.congested_fn = dm_any_congested; md->queue->backing_dev_info.congested_data = md; blk_queue_make_request(md->queue, dm_request); + blk_queue_ordered(md->queue, QUEUE_ORDERED_DRAIN, NULL); blk_queue_bounce_limit(md->queue, BLK_BOUNCE_ANY); md->queue->unplug_fn = dm_unplug_all; blk_queue_merge_bvec(md->queue, dm_merge_bvec); @@ -1140,6 +1135,7 @@ static struct mapped_device *alloc_dev(int minor) atomic_set(&md->pending, 0); init_waitqueue_head(&md->wait); + INIT_WORK(&md->work, dm_wq_work); init_waitqueue_head(&md->eventq); md->disk->major = _major; @@ -1379,18 +1375,24 @@ void dm_put(struct mapped_device *md) } EXPORT_SYMBOL_GPL(dm_put); -static int dm_wait_for_completion(struct mapped_device *md) +static int dm_wait_for_completion(struct mapped_device *md, int interruptible) { int r = 0; + DECLARE_WAITQUEUE(wait, current); + + dm_unplug_all(md->queue); + + add_wait_queue(&md->wait, &wait); while (1) { - set_current_state(TASK_INTERRUPTIBLE); + set_current_state(interruptible); smp_mb(); if (!atomic_read(&md->pending)) break; - if (signal_pending(current)) { + if (interruptible == TASK_INTERRUPTIBLE && + signal_pending(current)) { r = -EINTR; break; } @@ -1399,67 +1401,40 @@ static int dm_wait_for_completion(struct mapped_device *md) } set_current_state(TASK_RUNNING); + remove_wait_queue(&md->wait, &wait); + return r; } /* * Process the deferred bios */ -static void __flush_deferred_io(struct mapped_device *md) +static void dm_wq_work(struct work_struct *work) { + struct mapped_device *md = container_of(work, struct mapped_device, + work); struct bio *c; - while ((c = bio_list_pop(&md->deferred))) { - if (__split_bio(md, c)) - bio_io_error(c); - } - - clear_bit(DMF_BLOCK_IO, &md->flags); -} + down_write(&md->io_lock); -static void __merge_pushback_list(struct mapped_device *md) -{ - unsigned long flags; +next_bio: + spin_lock_irq(&md->deferred_lock); + c = bio_list_pop(&md->deferred); + spin_unlock_irq(&md->deferred_lock); - spin_lock_irqsave(&md->pushback_lock, flags); - clear_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); - bio_list_merge_head(&md->deferred, &md->pushback); - bio_list_init(&md->pushback); - spin_unlock_irqrestore(&md->pushback_lock, flags); -} + if (c) { + __split_and_process_bio(md, c); + goto next_bio; + } -static void dm_wq_work(struct work_struct *work) -{ - struct dm_wq_req *req = container_of(work, struct dm_wq_req, work); - struct mapped_device *md = req->md; + clear_bit(DMF_BLOCK_IO, &md->flags); - down_write(&md->io_lock); - switch (req->type) { - case DM_WQ_FLUSH_DEFERRED: - __flush_deferred_io(md); - break; - default: - DMERR("dm_wq_work: unrecognised work type %d", req->type); - BUG(); - } up_write(&md->io_lock); } -static void dm_wq_queue(struct mapped_device *md, int type, void *context, - struct dm_wq_req *req) -{ - req->type = type; - req->md = md; - req->context = context; - INIT_WORK(&req->work, dm_wq_work); - queue_work(md->wq, &req->work); -} - -static void dm_queue_flush(struct mapped_device *md, int type, void *context) +static void dm_queue_flush(struct mapped_device *md) { - struct dm_wq_req req; - - dm_wq_queue(md, type, context, &req); + queue_work(md->wq, &md->work); flush_workqueue(md->wq); } @@ -1534,7 +1509,6 @@ static void unlock_fs(struct mapped_device *md) int dm_suspend(struct mapped_device *md, unsigned suspend_flags) { struct dm_table *map = NULL; - DECLARE_WAITQUEUE(wait, current); int r = 0; int do_lockfs = suspend_flags & DM_SUSPEND_LOCKFS_FLAG ? 1 : 0; int noflush = suspend_flags & DM_SUSPEND_NOFLUSH_FLAG ? 1 : 0; @@ -1584,28 +1558,22 @@ int dm_suspend(struct mapped_device *md, unsigned suspend_flags) down_write(&md->io_lock); set_bit(DMF_BLOCK_IO, &md->flags); - add_wait_queue(&md->wait, &wait); up_write(&md->io_lock); - /* unplug */ - if (map) - dm_table_unplug_all(map); - /* * Wait for the already-mapped ios to complete. */ - r = dm_wait_for_completion(md); + r = dm_wait_for_completion(md, TASK_INTERRUPTIBLE); down_write(&md->io_lock); - remove_wait_queue(&md->wait, &wait); if (noflush) - __merge_pushback_list(md); + clear_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); up_write(&md->io_lock); /* were we interrupted ? */ if (r < 0) { - dm_queue_flush(md, DM_WQ_FLUSH_DEFERRED, NULL); + dm_queue_flush(md); unlock_fs(md); goto out; /* pushback list is already flushed, so skip flush */ @@ -1645,7 +1613,7 @@ int dm_resume(struct mapped_device *md) if (r) goto out; - dm_queue_flush(md, DM_WQ_FLUSH_DEFERRED, NULL); + dm_queue_flush(md); unlock_fs(md); diff --git a/drivers/md/dm.h b/drivers/md/dm.h index 20194e0..b48397c 100644 --- a/drivers/md/dm.h +++ b/drivers/md/dm.h @@ -60,7 +60,7 @@ int dm_table_barrier_ok(struct dm_table *t); int dm_target_init(void); void dm_target_exit(void); struct target_type *dm_get_target_type(const char *name); -void dm_put_target_type(struct target_type *t); +void dm_put_target_type(struct target_type *tt); int dm_target_iterate(void (*iter_func)(struct target_type *tt, void *param), void *param); diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h index 8209e08..66ec05a 100644 --- a/include/linux/device-mapper.h +++ b/include/linux/device-mapper.h @@ -139,6 +139,9 @@ struct target_type { dm_ioctl_fn ioctl; dm_merge_fn merge; dm_busy_fn busy; + + /* For internal device-mapper use. */ + struct list_head list; }; struct io_restrictions { diff --git a/include/linux/dm-dirty-log.h b/include/linux/dm-dirty-log.h index 600c5fb..5e8b11d 100644 --- a/include/linux/dm-dirty-log.h +++ b/include/linux/dm-dirty-log.h @@ -28,6 +28,9 @@ struct dm_dirty_log_type { const char *name; struct module *module; + /* For internal device-mapper use */ + struct list_head list; + int (*ctr)(struct dm_dirty_log *log, struct dm_target *ti, unsigned argc, char **argv); void (*dtr)(struct dm_dirty_log *log); @@ -113,6 +116,16 @@ struct dm_dirty_log_type { */ int (*status)(struct dm_dirty_log *log, status_type_t status_type, char *result, unsigned maxlen); + + /* + * is_remote_recovering is necessary for cluster mirroring. It provides + * a way to detect recovery on another node, so we aren't writing + * concurrently. This function is likely to block (when a cluster log + * is used). + * + * Returns: 0, 1 + */ + int (*is_remote_recovering)(struct dm_dirty_log *log, region_t region); }; int dm_dirty_log_type_register(struct dm_dirty_log_type *type); |
