dm raid1: use per_bio_data

Replace read_record_pool with per_bio_data in dm-raid1.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>

diff --git a/drivers/md/dm-raid1.c b/drivers/md/dm-raid1.c
index cec5f9b3a27817c7d5845b7ce02a69579b6c8a68..b4bc287bea7e2fb6bf3255b327e6eff1598ea07c 100644 (file)
--- a/drivers/md/dm-raid1.c
+++ b/drivers/md/dm-raid1.c
@@ -61,7 +61,6 @@ struct mirror_set {
        struct dm_region_hash *rh;
        struct dm_kcopyd_client *kcopyd_client;
        struct dm_io_client *io_client;
-       mempool_t *read_record_pool;
 
        /* recovery */
        region_t nr_regions;
@@ -139,14 +138,11 @@ static void dispatch_bios(void *context, struct bio_list *bio_list)
                queue_bio(ms, bio, WRITE);
 }
 
-#define MIN_READ_RECORDS 20
 struct dm_raid1_read_record {
        struct mirror *m;
        struct dm_bio_details details;
 };
 
-static struct kmem_cache *_dm_raid1_read_record_cache;
-
 /*
  * Every mirror should look like this one.
  */
@@ -876,19 +872,9 @@ static struct mirror_set *alloc_context(unsigned int nr_mirrors,
        atomic_set(&ms->suspend, 0);
        atomic_set(&ms->default_mirror, DEFAULT_MIRROR);
 
-       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);
-               return NULL;
-       }
-
        ms->io_client = dm_io_client_create();
        if (IS_ERR(ms->io_client)) {
                ti->error = "Error creating dm_io client";
-               mempool_destroy(ms->read_record_pool);
                kfree(ms);
                return NULL;
        }
@@ -900,7 +886,6 @@ static struct mirror_set *alloc_context(unsigned int nr_mirrors,
        if (IS_ERR(ms->rh)) {
                ti->error = "Error creating dirty region hash";
                dm_io_client_destroy(ms->io_client);
-               mempool_destroy(ms->read_record_pool);
                kfree(ms);
                return NULL;
        }
@@ -916,7 +901,6 @@ static void free_context(struct mirror_set *ms, struct dm_target *ti,
 
        dm_io_client_destroy(ms->io_client);
        dm_region_hash_destroy(ms->rh);
-       mempool_destroy(ms->read_record_pool);
        kfree(ms);
 }
 
@@ -1088,6 +1072,7 @@ static int mirror_ctr(struct dm_target *ti, unsigned int argc, char **argv)
 
        ti->num_flush_requests = 1;
        ti->num_discard_requests = 1;
+       ti->per_bio_data_size = sizeof(struct dm_raid1_read_record);
        ti->discard_zeroes_data_unsupported = true;
 
        ms->kmirrord_wq = alloc_workqueue("kmirrord",
@@ -1161,7 +1146,7 @@ static int mirror_map(struct dm_target *ti, struct bio *bio,
        int r, rw = bio_rw(bio);
        struct mirror *m;
        struct mirror_set *ms = ti->private;
-       struct dm_raid1_read_record *read_record = NULL;
+       struct dm_raid1_read_record *read_record;
        struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh);
 
        if (rw == WRITE) {
@@ -1194,7 +1179,7 @@ static int mirror_map(struct dm_target *ti, struct bio *bio,
        if (unlikely(!m))
                return -EIO;
 
-       read_record = mempool_alloc(ms->read_record_pool, GFP_NOIO);
+       read_record = dm_per_bio_data(bio, sizeof(struct dm_raid1_read_record));
        dm_bio_record(&read_record->details, bio);
        map_context->ptr = read_record;
        read_record->m = m;
@@ -1254,7 +1239,6 @@ static int mirror_end_io(struct dm_target *ti, struct bio *bio,
                        bd = &read_record->details;
 
                        dm_bio_restore(bd, bio);
-                       mempool_free(read_record, ms->read_record_pool);
                        map_context->ptr = NULL;
                        queue_bio(ms, bio, rw);
                        return DM_ENDIO_INCOMPLETE;
@@ -1263,10 +1247,7 @@ static int mirror_end_io(struct dm_target *ti, struct bio *bio,
        }
 
 out:
-       if (read_record) {
-               mempool_free(read_record, ms->read_record_pool);
-               map_context->ptr = NULL;
-       }
+       map_context->ptr = NULL;
 
        return error;
 }
@@ -1420,7 +1401,7 @@ static int mirror_iterate_devices(struct dm_target *ti,
 
 static struct target_type mirror_target = {
        .name    = "mirror",
-       .version = {1, 12, 1},
+       .version = {1, 13, 1},
        .module  = THIS_MODULE,
        .ctr     = mirror_ctr,
        .dtr     = mirror_dtr,
@@ -1437,13 +1418,6 @@ 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) {
                DMERR("Failed to register mirror target");
@@ -1453,15 +1427,12 @@ static int __init dm_mirror_init(void)
        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 */