flow_dissector: add mpls support (v2)

Add support for parsing MPLS flows to the flow dissector in preparation for
adding MPLS match support to cls_flower.

Signed-off-by: Benjamin LaHaise <benjamin.lahaise@netronome.com>
Signed-off-by: Benjamin LaHaise <bcrl@kvack.org>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Simon Horman <simon.horman@netronome.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Jiri Pirko <jiri@mellanox.com>
Cc: Eric Dumazet <jhs@mojatatu.com>
Cc: Hadar Hen Zion <hadarh@mellanox.com>
Cc: Gao Feng <fgao@ikuai8.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/flow_dissector.h b/include/net/flow_dissector.h
index ac97030..8d21d44 100644
--- a/include/net/flow_dissector.h
+++ b/include/net/flow_dissector.h
@@ -41,6 +41,13 @@ struct flow_dissector_key_vlan {
 	u16	padding;
 };
 
+struct flow_dissector_key_mpls {
+	u32	mpls_ttl:8,
+		mpls_bos:1,
+		mpls_tc:3,
+		mpls_label:20;
+};
+
 struct flow_dissector_key_keyid {
 	__be32	keyid;
 };
@@ -169,6 +176,7 @@ enum flow_dissector_key_id {
 	FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS, /* struct flow_dissector_key_ipv6_addrs */
 	FLOW_DISSECTOR_KEY_ENC_CONTROL, /* struct flow_dissector_key_control */
 	FLOW_DISSECTOR_KEY_ENC_PORTS, /* struct flow_dissector_key_ports */
+	FLOW_DISSECTOR_KEY_MPLS, /* struct flow_dissector_key_mpls */
 
 	FLOW_DISSECTOR_KEY_MAX,
 };