When reading the refcount table entry in get_refcount(), only bits which
are actually significant for the refcount block offset should be taken
into account.
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NLaszlo Ersek <lersek@redhat.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>