dm request: add caches
This patch prepares some kmem_caches for request-based dm.
Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 8237141..4882ce7 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -32,6 +32,7 @@
static DEFINE_SPINLOCK(_minor_lock);
/*
+ * For bio-based dm.
* One of these is allocated per bio.
*/
struct dm_io {
@@ -43,6 +44,7 @@
};
/*
+ * For bio-based dm.
* One of these is allocated per target within a bio. Hopefully
* this will be simplified out one day.
*/
@@ -54,6 +56,27 @@
DEFINE_TRACE(block_bio_complete);
+/*
+ * For request-based dm.
+ * One of these is allocated per request.
+ */
+struct dm_rq_target_io {
+ struct mapped_device *md;
+ struct dm_target *ti;
+ struct request *orig, clone;
+ int error;
+ union map_info info;
+};
+
+/*
+ * For request-based dm.
+ * One of these is allocated per bio.
+ */
+struct dm_rq_clone_bio_info {
+ struct bio *orig;
+ struct request *rq;
+};
+
union map_info *dm_get_mapinfo(struct bio *bio)
{
if (bio && bio->bi_private)
@@ -149,6 +172,8 @@
#define MIN_IOS 256
static struct kmem_cache *_io_cache;
static struct kmem_cache *_tio_cache;
+static struct kmem_cache *_rq_tio_cache;
+static struct kmem_cache *_rq_bio_info_cache;
static int __init local_init(void)
{
@@ -164,9 +189,17 @@
if (!_tio_cache)
goto out_free_io_cache;
+ _rq_tio_cache = KMEM_CACHE(dm_rq_target_io, 0);
+ if (!_rq_tio_cache)
+ goto out_free_tio_cache;
+
+ _rq_bio_info_cache = KMEM_CACHE(dm_rq_clone_bio_info, 0);
+ if (!_rq_bio_info_cache)
+ goto out_free_rq_tio_cache;
+
r = dm_uevent_init();
if (r)
- goto out_free_tio_cache;
+ goto out_free_rq_bio_info_cache;
_major = major;
r = register_blkdev(_major, _name);
@@ -180,6 +213,10 @@
out_uevent_exit:
dm_uevent_exit();
+out_free_rq_bio_info_cache:
+ kmem_cache_destroy(_rq_bio_info_cache);
+out_free_rq_tio_cache:
+ kmem_cache_destroy(_rq_tio_cache);
out_free_tio_cache:
kmem_cache_destroy(_tio_cache);
out_free_io_cache:
@@ -190,6 +227,8 @@
static void local_exit(void)
{
+ kmem_cache_destroy(_rq_bio_info_cache);
+ kmem_cache_destroy(_rq_tio_cache);
kmem_cache_destroy(_tio_cache);
kmem_cache_destroy(_io_cache);
unregister_blkdev(_major, _name);