dm: Use kzalloc for all structs with embedded biosets/mempools

mempool_init()/bioset_init() require that the mempools/biosets be zeroed
first; they probably should not _require_ this, but not allocating those
structs with kzalloc is a fairly nonsensical thing to do (calling
mempool_exit()/bioset_exit() on an uninitialized mempool/bioset is legal
and safe, but only works if said memory was zeroed.)

Acked-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

drivers/md/dm-bio-prison-v1.c

@@ -33,7 +33,7 @@ static struct kmem_cache *_cell_cache;
  */
 struct dm_bio_prison *dm_bio_prison_create(void)
 {
-	struct dm_bio_prison *prison = kmalloc(sizeof(*prison), GFP_KERNEL);
+	struct dm_bio_prison *prison = kzalloc(sizeof(*prison), GFP_KERNEL);
 	int ret;
 
 	if (!prison)

drivers/md/dm-bio-prison-v2.c

@@ -35,7 +35,7 @@ static struct kmem_cache *_cell_cache;
  */
 struct dm_bio_prison_v2 *dm_bio_prison_create_v2(struct workqueue_struct *wq)
 {
-	struct dm_bio_prison_v2 *prison = kmalloc(sizeof(*prison), GFP_KERNEL);
+	struct dm_bio_prison_v2 *prison = kzalloc(sizeof(*prison), GFP_KERNEL);
 	int ret;
 
 	if (!prison)

drivers/md/dm-io.c

@@ -51,7 +51,7 @@ struct dm_io_client *dm_io_client_create(void)
 	unsigned min_ios = dm_get_reserved_bio_based_ios();
 	int ret;
 
-	client = kmalloc(sizeof(*client), GFP_KERNEL);
+	client = kzalloc(sizeof(*client), GFP_KERNEL);
 	if (!client)
 		return ERR_PTR(-ENOMEM);
 

drivers/md/dm-kcopyd.c

@@ -882,7 +882,7 @@ struct dm_kcopyd_client *dm_kcopyd_client_create(struct dm_kcopyd_throttle *thro
 	int r;
 	struct dm_kcopyd_client *kc;
 
-	kc = kmalloc(sizeof(*kc), GFP_KERNEL);
+	kc = kzalloc(sizeof(*kc), GFP_KERNEL);
 	if (!kc)
 		return ERR_PTR(-ENOMEM);
 

drivers/md/dm-region-hash.c

@@ -180,7 +180,7 @@ struct dm_region_hash *dm_region_hash_create(
 		;
 	nr_buckets >>= 1;
 
-	rh = kmalloc(sizeof(*rh), GFP_KERNEL);
+	rh = kzalloc(sizeof(*rh), GFP_KERNEL);
 	if (!rh) {
 		DMERR("unable to allocate region hash memory");
 		return ERR_PTR(-ENOMEM);

drivers/md/dm-snap.c

@@ -1120,7 +1120,7 @@ static int snapshot_ctr(struct dm_target *ti, unsigned int argc, char **argv)
 		origin_mode = FMODE_WRITE;
 	}
 
-	s = kmalloc(sizeof(*s), GFP_KERNEL);
+	s = kzalloc(sizeof(*s), GFP_KERNEL);
 	if (!s) {
 		ti->error = "Cannot allocate private snapshot structure";
 		r = -ENOMEM;

drivers/md/dm-thin.c

@@ -2861,7 +2861,7 @@ static struct pool *pool_create(struct mapped_device *pool_md,
 		return (struct pool *)pmd;
 	}
 
-	pool = kmalloc(sizeof(*pool), GFP_KERNEL);
+	pool = kzalloc(sizeof(*pool), GFP_KERNEL);
 	if (!pool) {
 		*error = "Error allocating memory for pool";
 		err_p = ERR_PTR(-ENOMEM);