ceph: allow object copies across different filesystems in the same cluster
OSDs are able to perform object copies across different pools. Thus,
there's no need to prevent copy_file_range from doing remote copies if the
source and destination superblocks are different. Only return -EXDEV if
they have different fsid (the cluster ID).
Signed-off-by: Luis Henriques <firstname.lastname@example.org>
Reviewed-by: Jeff Layton <email@example.com>
Signed-off-by: Ilya Dryomov <firstname.lastname@example.org>