btrfs: cleanup noused initialization of dev in btrfs_end_bio()

It is introduced by:
 c404e0dc2c843b154f9a36c3aec10d0a715d88eb
 Btrfs: fix use-after-free in the finishing procedure of the device replace

But seems no relationship with that bug, this patch revirt these
code block for cleanup.

Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 8396699..d4cd405 100644 (file)
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -5715,7 +5715,6 @@ static inline void btrfs_end_bbio(struct btrfs_bio *bbio, struct bio *bio, int e
 static void btrfs_end_bio(struct bio *bio, int err)
 {
        struct btrfs_bio *bbio = bio->bi_private;
-       struct btrfs_device *dev = bbio->stripes[0].dev;
        int is_orig_bio = 0;
 
        if (err) {
@@ -5723,6 +5722,7 @@ static void btrfs_end_bio(struct bio *bio, int err)
                if (err == -EIO || err == -EREMOTEIO) {
                        unsigned int stripe_index =
                                btrfs_io_bio(bio)->stripe_index;
+                       struct btrfs_device *dev;
 
                        BUG_ON(stripe_index >= bbio->num_stripes);
                        dev = bbio->stripes[stripe_index].dev;