- * TCP segmentation offload. To enable this offload feature for a
- * packet to be transmitted on hardware supporting TSO:
- * - set the PKT_TX_TCP_SEG flag in mbuf->ol_flags (this flag implies
- * PKT_TX_TCP_CKSUM)
- * - set the flag PKT_TX_IPV4 or PKT_TX_IPV6
- * - if it's IPv4, set the PKT_TX_IP_CKSUM flag and write the IP checksum
- * to 0 in the packet
- * - fill the mbuf offload information: l2_len, l3_len, l4_len, tso_segsz
- * - calculate the pseudo header checksum without taking ip_len in accound,
- * and set it in the TCP header. Refer to rte_ipv4_phdr_cksum() and
- * rte_ipv6_phdr_cksum() that can be used as helpers.
+ * Offload the IP checksum of an external header in the hardware. The
+ * flag PKT_TX_OUTER_IPV4 should also be set by the application, alto ugh
+ * a PMD will only check PKT_TX_IP_CKSUM. The IP checksum field in the
+ * packet must be set to 0.
+ * - set the outer IP checksum field in the packet to 0
+ * - fill the mbuf offload information: outer_l2_len, outer_l3_len
+ */
+#define PKT_TX_OUTER_IP_CKSUM (1ULL << 58)
+
+/**
+ * Packet outer header is IPv4. This flag must be set when using any
+ * outer offload feature (L3 or L4 checksum) to tell the NIC that the
+ * outer header of the tunneled packet is an IPv4 packet.
+ */
+#define PKT_TX_OUTER_IPV4 (1ULL << 59)
+
+/**
+ * Packet outer header is IPv6. This flag must be set when using any
+ * outer offload feature (L4 checksum) to tell the NIC that the outer
+ * header of the tunneled packet is an IPv6 packet.