+struct flow {
+ ovs_be32 tun_id; /* Encapsulating tunnel ID. */
+ ovs_be32 nw_src; /* IP source address. */
+ ovs_be32 nw_dst; /* IP destination address. */
+ uint16_t in_port; /* Input switch port. */
+ ovs_be16 dl_vlan; /* Input VLAN. */
+ ovs_be16 dl_type; /* Ethernet frame type. */
+ ovs_be16 tp_src; /* TCP/UDP source port. */
+ ovs_be16 tp_dst; /* TCP/UDP destination port. */
+ uint8_t dl_src[6]; /* Ethernet source address. */
+ uint8_t dl_dst[6]; /* Ethernet destination address. */
+ uint8_t nw_proto; /* IP protocol or low 8 bits of ARP opcode. */
+ uint8_t dl_vlan_pcp; /* Input VLAN priority. */
+ uint8_t nw_tos; /* IP ToS (DSCP field, 6 bits). */
+};
+
+/* Assert that there are FLOW_SIG_SIZE bytes of significant data in "struct
+ * flow", followed by FLOW_PAD_SIZE bytes of padding. */
+#define FLOW_SIG_SIZE 37
+#define FLOW_PAD_SIZE 3
+BUILD_ASSERT_DECL(offsetof(struct flow, nw_tos) == FLOW_SIG_SIZE - 1);
+BUILD_ASSERT_DECL(sizeof(((struct flow *)0)->nw_tos) == 1);
+BUILD_ASSERT_DECL(sizeof(struct flow) == FLOW_SIG_SIZE + FLOW_PAD_SIZE);