diff options
Diffstat (limited to 'fs/overlayfs')
| -rw-r--r-- | fs/overlayfs/super.c | 19 |
1 files changed, 15 insertions, 4 deletions
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c index 13a8a8617e44..76440feb79f6 100644 --- a/fs/overlayfs/super.c +++ b/fs/overlayfs/super.c @@ -252,6 +252,7 @@ static void ovl_put_super(struct super_block *sb) ovl_free_fs(ofs); } +/* Sync real dirty inodes in upper filesystem (if it exists) */ static int ovl_sync_fs(struct super_block *sb, int wait) { struct ovl_fs *ofs = sb->s_fs_info; @@ -260,14 +261,24 @@ static int ovl_sync_fs(struct super_block *sb, int wait) if (!ofs->upper_mnt) return 0; - upper_sb = ofs->upper_mnt->mnt_sb; - if (!upper_sb->s_op->sync_fs) + + /* + * If this is a sync(2) call or an emergency sync, all the super blocks + * will be iterated, including upper_sb, so no need to do anything. + * + * If this is a syncfs(2) call, then we do need to call + * sync_filesystem() on upper_sb, but enough if we do it when being + * called with wait == 1. + */ + if (!wait) return 0; - /* real inodes have already been synced by sync_filesystem(ovl_sb) */ + upper_sb = ofs->upper_mnt->mnt_sb; + down_read(&upper_sb->s_umount); - ret = upper_sb->s_op->sync_fs(upper_sb, wait); + ret = sync_filesystem(upper_sb); up_read(&upper_sb->s_umount); + return ret; } |