btrfs: copy fsid to super_block s_uuid
authorAnand Jain <anand.jain@oracle.com>
Tue, 1 Aug 2017 10:35:08 +0000 (18:35 +0800)
committerDavid Sterba <dsterba@suse.com>
Mon, 30 Oct 2017 11:27:55 +0000 (12:27 +0100)
commitee87cf5ed9fe8e41d057f5f5c7f49c18b6d3f94c
tree800bed282b3056062e3a160e093765c38bc096c9
parent718dc5fade1a97cff58aa6581d05c0ab8a9fcf1d
btrfs: copy fsid to super_block s_uuid

We didn't copy fsid to struct super_block.s_uuid so Overlay disables
index feature with btrfs as the lower FS.

kernel: overlayfs: fs on '/lower' does not support file handles, falling back to index=off.

Fix this by publishing the fsid through struct super_block.s_uuid.

[ dsterba: I think that setting s_uuid is the last missing bit. Overlay
  needs the file handle encoding support from the lower filesystem, which
  is supported. Filling the whole filesystem id is correct, the subvolume
  id is encoded in the file handle buffer from inside btrfs_encode_fh. ]

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
fs/btrfs/disk-io.c