Btrfs: fix remount vs autodefrag

If we remount the fs to close the auto defragment or make the fs R/O,
we should stop the auto defragment.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>

1 files changed, 5 insertions, 0 deletions

diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 9f67e623206d..6e6dd8cdad92 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -374,6 +374,11 @@ int btrfs_run_defrag_inodes(struct btrfs_fs_info *fs_info)
 
         atomic_inc(&fs_info->defrag_running);
         while(1) {
+                /* Pause the auto defragger. */
+                if (test_bit(BTRFS_FS_STATE_REMOUNTING,
+                             &fs_info->fs_state))
+                        break;
+
                 if (!__need_auto_defrag(fs_info->tree_root))
                         break;