It's protected by the s_gen_ttl_lock, so we should fetch under it
and ensure that we're using the same generation in both places.
Signed-off-by: NJeff Layton <jlayton@kernel.org>
Reviewed-by: N"Yan, Zheng" <zyan@redhat.com>
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>