From a822c83e47d97cdef38c4352e1ef62d9f46cfe98 Mon Sep 17 00:00:00 2001 From: Joe Thornber Date: Fri, 3 Jul 2015 10:22:42 +0100 Subject: [PATCH] dm thin: allocate the cell_sort_array dynamically Given the pool's cell_sort_array holds 8192 pointers it triggers an order 5 allocation via kmalloc. This order 5 allocation is prone to failure as system memory gets more fragmented over time. Fix this by allocating the cell_sort_array using vmalloc. Signed-off-by: Joe Thornber Signed-off-by: Mike Snitzer Cc: stable@vger.kernel.org --- drivers/md/dm-thin.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c index c33f61a4cc28..8f015d924a24 100644 --- a/drivers/md/dm-thin.c +++ b/drivers/md/dm-thin.c @@ -18,6 +18,7 @@ #include #include #include +#include #include #include @@ -268,7 +269,7 @@ struct pool { process_mapping_fn process_prepared_mapping; process_mapping_fn process_prepared_discard; - struct dm_bio_prison_cell *cell_sort_array[CELL_SORT_ARRAY_SIZE]; + struct dm_bio_prison_cell **cell_sort_array; }; static enum pool_mode get_pool_mode(struct pool *pool); @@ -2777,6 +2778,7 @@ static void __pool_destroy(struct pool *pool) { __pool_table_remove(pool); + vfree(pool->cell_sort_array); if (dm_pool_metadata_close(pool->pmd) < 0) DMWARN("%s: dm_pool_metadata_close() failed.", __func__); @@ -2889,6 +2891,13 @@ static struct pool *pool_create(struct mapped_device *pool_md, goto bad_mapping_pool; } + pool->cell_sort_array = vmalloc(sizeof(*pool->cell_sort_array) * CELL_SORT_ARRAY_SIZE); + if (!pool->cell_sort_array) { + *error = "Error allocating cell sort array"; + err_p = ERR_PTR(-ENOMEM); + goto bad_sort_array; + } + pool->ref_count = 1; pool->last_commit_jiffies = jiffies; pool->pool_md = pool_md; @@ -2897,6 +2906,8 @@ static struct pool *pool_create(struct mapped_device *pool_md, return pool; +bad_sort_array: + mempool_destroy(pool->mapping_pool); bad_mapping_pool: dm_deferred_set_destroy(pool->all_io_ds); bad_all_io_ds: