'mount an lv.
:param lowerdir: name/path of the lower directory
:type lowerdir: ``str``
:param upperdir: name/path of the upper directory
:type upperdir: ``str``
:param mount_point: path on the file system that is mounted.
:type mount_point: ``str``'

def _overlayfs_mount(self, lowerdir, upperdir, mount_point):

    build_command = [self.module.get_bin_path('mount', True), '-t    overlayfs', ('-o    lowerdir=%s,upperdir=%s' % (lowerdir, upperdir)), 'overlayfs', mount_point]
    (rc, stdout, err) = self._run_command(build_command)
    if (rc != 0):
        self.failure(err=err, rc=rc, msg=('failed    to    mount    overlayfs:%s:%s    to    %s    --    Command:    %s' % (lowerdir, upperdir, mount_point, build_command)))
