[PATCH 4.17 070/336] f2fs: fix to dont trigger writeback during recovery

[Greg Kroah-Hartman]

4.17-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Chao Yu <yuchao0@xxxxxxxxxx>

[ Upstream commit 64c74a7ab505ea40d1b3e5d02735ecab08ae1b14 ]

- f2fs_fill_super
 - recover_fsync_data
  - recover_data
   - del_fsync_inode
    - iput
     - iput_final
      - write_inode_now
       - f2fs_write_inode
        - f2fs_balance_fs
         - f2fs_balance_fs_bg
          - sync_dirty_inodes

With data_flush mount option, during recovery, in order to avoid entering
above writeback flow, let's detect recovery status and do skip in
f2fs_balance_fs_bg.

Signed-off-by: Chao Yu <yuchao0@xxxxxxxxxx>
Signed-off-by: Yunlei He <heyunlei@xxxxxxxxxx>
Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 fs/f2fs/segment.c |    3 +++
 1 file changed, 3 insertions(+)

--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -478,6 +478,9 @@ void f2fs_balance_fs(struct f2fs_sb_info
 
 void f2fs_balance_fs_bg(struct f2fs_sb_info *sbi)
 {
+	if (unlikely(is_sbi_flag_set(sbi, SBI_POR_DOING)))
+		return;
+
 	/* try to shrink extent cache when there is no enough memory */
 	if (!available_free_memory(sbi, EXTENT_CACHE))
 		f2fs_shrink_extent_tree(sbi, EXTENT_CACHE_SHRINK_NUMBER);