dm thin: cleanup dead code

Remove unused @data_block parameter from cell_defer.
Change thin_bio_map to use many returns rather than setting a variable.

Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>

diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c
index 2cb81bf3a8e38f036f4e766c31a201ecfdc0523f..6b9322e63651eef4fe61a0e12748ecfe44b190d7 100644 (file)
--- a/drivers/md/dm-thin.c
+++ b/drivers/md/dm-thin.c
@@ -510,8 +510,7 @@ static void overwrite_endio(struct bio *bio, int err)
 /*
  * This sends the bios in the cell back to the deferred_bios list.
  */
-static void cell_defer(struct thin_c *tc, struct dm_bio_prison_cell *cell,
-                      dm_block_t data_block)
+static void cell_defer(struct thin_c *tc, struct dm_bio_prison_cell *cell)
 {
        struct pool *pool = tc->pool;
        unsigned long flags;
@@ -528,12 +527,9 @@ static void cell_defer(struct thin_c *tc, struct dm_bio_prison_cell *cell,
  */
 static void cell_defer_no_holder(struct thin_c *tc, struct dm_bio_prison_cell *cell)
 {
-       struct bio_list bios;
        struct pool *pool = tc->pool;
        unsigned long flags;
 
-       bio_list_init(&bios);
-
        spin_lock_irqsave(&pool->lock, flags);
        dm_cell_release_no_holder(cell, &pool->deferred_bios);
        spin_unlock_irqrestore(&pool->lock, flags);
@@ -586,7 +582,7 @@ static void process_prepared_mapping(struct dm_thin_new_mapping *m)
                cell_defer_no_holder(tc, m->cell);
                bio_endio(bio, 0);
        } else
-               cell_defer(tc, m->cell, m->data_block);
+               cell_defer(tc, m->cell);
 
 out:
        list_del(&m->list);
@@ -1447,8 +1443,7 @@ static int thin_bio_map(struct dm_target *ti, struct bio *bio,
                         * of doing so.  Just error it.
                         */
                        bio_io_error(bio);
-                       r = DM_MAPIO_SUBMITTED;
-                       break;
+                       return DM_MAPIO_SUBMITTED;
                }
                /* fall through */
 
@@ -1458,8 +1453,7 @@ static int thin_bio_map(struct dm_target *ti, struct bio *bio,
                 * provide the hint to load the metadata into cache.
                 */
                thin_defer_bio(tc, bio);
-               r = DM_MAPIO_SUBMITTED;
-               break;
+               return DM_MAPIO_SUBMITTED;
 
        default:
                /*
@@ -1468,11 +1462,8 @@ static int thin_bio_map(struct dm_target *ti, struct bio *bio,
                 * pool is switched to fail-io mode.
                 */
                bio_io_error(bio);
-               r = DM_MAPIO_SUBMITTED;
-               break;
+               return DM_MAPIO_SUBMITTED;
        }
-
-       return r;
 }
 
 static int pool_is_congested(struct dm_target_callbacks *cb, int bdi_bits)