Btrfs: fix infinite loop in btrfs_shrink_device()
If relocate of block group 0 fails with ENOSPC we end up infinitely
looping because key.offset -= 1 statement in that case brings us back to
where we started.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index bcc0acd..be2d4e0 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -2987,7 +2987,7 @@
key.offset = (u64)-1;
key.type = BTRFS_DEV_EXTENT_KEY;
- while (1) {
+ do {
ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
if (ret < 0)
goto done;
@@ -3029,8 +3029,7 @@
goto done;
if (ret == -ENOSPC)
failed++;
- key.offset -= 1;
- }
+ } while (key.offset-- > 0);
if (failed && !retried) {
failed = 0;