Btrfs: remove unnecessary code of stripe_index assignment in __btrfs_map_block

stripe_index's value was set again in latter line:
stripe_index = 0;

Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
(cherry picked from commit 6de65650758e819d3dfdc621010dcd6117e8d186)

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 01920515f90d4cfc4fa5c13b9dcca0a5e8a6a6b4..a91102d50f163d7ec59d74faa67c5bb39cd891d1 100644 (file)
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -5173,9 +5173,7 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
 
                        /* push stripe_nr back to the start of the full stripe */
                        stripe_nr = raid56_full_stripe_start;
-                       do_div(stripe_nr, stripe_len);
-
-                       stripe_index = do_div(stripe_nr, nr_data_stripes(map));
+                       do_div(stripe_nr, stripe_len * nr_data_stripes(map));
 
                        /* RAID[56] write or recovery. Return all stripes */
                        num_stripes = map->num_stripes;