From: Mikulas Patocka This patch removes endio_hook_pool from dm-thin and uses per-bio data instead. This patch removes any use of map_info in preparation for the next patch that removes map_info from bio-based device mapper. Signed-off-by: Mikulas Patocka Signed-off-by: Alasdair G Kergon --- drivers/md/dm-thin.c | 49 +++++++++++++------------------------------------ 1 file changed, 13 insertions(+), 36 deletions(-) Index: linux/drivers/md/dm-thin.c =================================================================== --- linux.orig/drivers/md/dm-thin.c +++ linux/drivers/md/dm-thin.c @@ -186,7 +186,6 @@ struct pool { struct dm_thin_new_mapping *next_mapping; mempool_t *mapping_pool; - mempool_t *endio_hook_pool; process_bio_fn process_bio; process_bio_fn process_discard; @@ -304,7 +303,7 @@ static void __requeue_bio_list(struct th bio_list_init(master); while ((bio = bio_list_pop(&bios))) { - struct dm_thin_endio_hook *h = dm_get_mapinfo(bio)->ptr; + struct dm_thin_endio_hook *h = dm_per_bio_data(bio, sizeof(struct dm_thin_endio_hook)); if (h->tc == tc) bio_endio(bio, DM_ENDIO_REQUEUE); @@ -375,7 +374,7 @@ static void inc_all_io_entry(struct pool if (bio->bi_rw & REQ_DISCARD) return; - h = dm_get_mapinfo(bio)->ptr; + h = dm_per_bio_data(bio, sizeof(struct dm_thin_endio_hook)); h->all_io_entry = dm_deferred_entry_inc(pool->all_io_ds); } @@ -485,7 +484,7 @@ static void copy_complete(int read_err, static void overwrite_endio(struct bio *bio, int err) { unsigned long flags; - struct dm_thin_endio_hook *h = dm_get_mapinfo(bio)->ptr; + struct dm_thin_endio_hook *h = dm_per_bio_data(bio, sizeof(struct dm_thin_endio_hook)); struct dm_thin_new_mapping *m = h->overwrite_mapping; struct pool *pool = m->tc->pool; @@ -714,7 +713,7 @@ static void schedule_copy(struct thin_c * bio immediately. Otherwise we use kcopyd to clone the data first. */ if (io_overwrites_block(pool, bio)) { - struct dm_thin_endio_hook *h = dm_get_mapinfo(bio)->ptr; + struct dm_thin_endio_hook *h = dm_per_bio_data(bio, sizeof(struct dm_thin_endio_hook)); h->overwrite_mapping = m; m->bio = bio; @@ -784,7 +783,7 @@ static void schedule_zero(struct thin_c process_prepared_mapping(m); else if (io_overwrites_block(pool, bio)) { - struct dm_thin_endio_hook *h = dm_get_mapinfo(bio)->ptr; + struct dm_thin_endio_hook *h = dm_per_bio_data(bio, sizeof(struct dm_thin_endio_hook)); h->overwrite_mapping = m; m->bio = bio; @@ -899,7 +898,7 @@ static int alloc_data_block(struct thin_ */ static void retry_on_resume(struct bio *bio) { - struct dm_thin_endio_hook *h = dm_get_mapinfo(bio)->ptr; + struct dm_thin_endio_hook *h = dm_per_bio_data(bio, sizeof(struct dm_thin_endio_hook)); struct thin_c *tc = h->tc; struct pool *pool = tc->pool; unsigned long flags; @@ -1051,7 +1050,7 @@ static void process_shared_bio(struct th if (bio_data_dir(bio) == WRITE && bio->bi_size) break_sharing(tc, bio, block, &key, lookup_result, cell); else { - struct dm_thin_endio_hook *h = dm_get_mapinfo(bio)->ptr; + struct dm_thin_endio_hook *h = dm_per_bio_data(bio, sizeof(struct dm_thin_endio_hook)); h->shared_read_entry = dm_deferred_entry_inc(pool->shared_read_ds); inc_all_io_entry(pool, bio); @@ -1226,7 +1225,7 @@ static void process_deferred_bios(struct spin_unlock_irqrestore(&pool->lock, flags); while ((bio = bio_list_pop(&bios))) { - struct dm_thin_endio_hook *h = dm_get_mapinfo(bio)->ptr; + struct dm_thin_endio_hook *h = dm_per_bio_data(bio, sizeof(struct dm_thin_endio_hook)); struct thin_c *tc = h->tc; /* @@ -1359,17 +1358,14 @@ static void thin_defer_bio(struct thin_c wake_worker(pool); } -static struct dm_thin_endio_hook *thin_hook_bio(struct thin_c *tc, struct bio *bio) +static void thin_hook_bio(struct thin_c *tc, struct bio *bio) { - struct pool *pool = tc->pool; - struct dm_thin_endio_hook *h = mempool_alloc(pool->endio_hook_pool, GFP_NOIO); + struct dm_thin_endio_hook *h = dm_per_bio_data(bio, sizeof(struct dm_thin_endio_hook)); h->tc = tc; h->shared_read_entry = NULL; h->all_io_entry = NULL; h->overwrite_mapping = NULL; - - return h; } /* @@ -1386,7 +1382,7 @@ static int thin_bio_map(struct dm_target struct dm_bio_prison_cell *cell1, *cell2; struct dm_cell_key key; - map_context->ptr = thin_hook_bio(tc, bio); + thin_hook_bio(tc, bio); if (get_pool_mode(tc->pool) == PM_FAIL) { bio_io_error(bio); @@ -1595,14 +1591,12 @@ static void __pool_destroy(struct pool * if (pool->next_mapping) mempool_free(pool->next_mapping, pool->mapping_pool); mempool_destroy(pool->mapping_pool); - mempool_destroy(pool->endio_hook_pool); dm_deferred_set_destroy(pool->shared_read_ds); dm_deferred_set_destroy(pool->all_io_ds); kfree(pool); } static struct kmem_cache *_new_mapping_cache; -static struct kmem_cache *_endio_hook_cache; static struct pool *pool_create(struct mapped_device *pool_md, struct block_device *metadata_dev, @@ -1696,13 +1690,6 @@ static struct pool *pool_create(struct m goto bad_mapping_pool; } - pool->endio_hook_pool = mempool_create_slab_pool(ENDIO_HOOK_POOL_SIZE, - _endio_hook_cache); - if (!pool->endio_hook_pool) { - *error = "Error creating pool's endio_hook mempool"; - err_p = ERR_PTR(-ENOMEM); - goto bad_endio_hook_pool; - } pool->ref_count = 1; pool->last_commit_jiffies = jiffies; pool->pool_md = pool_md; @@ -1711,8 +1698,6 @@ static struct pool *pool_create(struct m return pool; -bad_endio_hook_pool: - mempool_destroy(pool->mapping_pool); bad_mapping_pool: dm_deferred_set_destroy(pool->all_io_ds); bad_all_io_ds: @@ -2607,6 +2592,7 @@ static int thin_ctr(struct dm_target *ti ti->num_flush_requests = 1; ti->flush_supported = true; + ti->per_bio_data_size = sizeof(struct dm_thin_endio_hook); /* In case the pool supports discards, pass them on. */ if (tc->pool->pf.discard_enabled) { @@ -2653,7 +2639,7 @@ static int thin_endio(struct dm_target * union map_info *map_context) { unsigned long flags; - struct dm_thin_endio_hook *h = map_context->ptr; + struct dm_thin_endio_hook *h = dm_per_bio_data(bio, sizeof(struct dm_thin_endio_hook)); struct list_head work; struct dm_thin_new_mapping *m, *tmp; struct pool *pool = h->tc->pool; @@ -2683,8 +2669,6 @@ static int thin_endio(struct dm_target * } } - mempool_free(h, pool->endio_hook_pool); - return 0; } @@ -2813,14 +2797,8 @@ static int __init dm_thin_init(void) if (!_new_mapping_cache) goto bad_new_mapping_cache; - _endio_hook_cache = KMEM_CACHE(dm_thin_endio_hook, 0); - if (!_endio_hook_cache) - goto bad_endio_hook_cache; - return 0; -bad_endio_hook_cache: - kmem_cache_destroy(_new_mapping_cache); bad_new_mapping_cache: dm_unregister_target(&pool_target); bad_pool_target: @@ -2835,7 +2813,6 @@ static void dm_thin_exit(void) dm_unregister_target(&pool_target); kmem_cache_destroy(_new_mapping_cache); - kmem_cache_destroy(_endio_hook_cache); } module_init(dm_thin_init);