Btrfs-progs: fix detection of root objects in cmds-property.c
Several fixes:
1) The function check_is_root() returns 0 if the object is root;
2) Don't treat any error from get fsid ioctl as meaning the target
is root. Only -ENOTTY means it's a root (parent directory is
not a btrfs fs) and a -ENOTDIR means our target object is not a
directory, therefore it can be the root;
3) Fix the comparison of the target and target's parent fs ids. If
they are different, it means the target is a mount point in a
btrfs fs, therefore it's a root, otherwise it isn't.
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>