examples/ip_frag: fix use of ethdev internal device array

[dpdk.git] / lib / librte_mbuf / rte_mbuf.h

diff --git a/lib/librte_mbuf/rte_mbuf.h b/lib/librte_mbuf/rte_mbuf.h
index 9542488..98225ec 100644 (file)
--- a/lib/librte_mbuf/rte_mbuf.h
+++ b/lib/librte_mbuf/rte_mbuf.h
@@ -702,7 +702,18 @@ struct rte_mbuf {
                        uint64_t tso_segsz:RTE_MBUF_TSO_SEGSZ_BITS;
                        /**< TCP TSO segment size */
 
-                       /* fields for TX offloading of tunnels */
+                       /*
+                        * Fields for Tx offloading of tunnels.
+                        * These are undefined for packets which don't request
+                        * any tunnel offloads (outer IP or UDP checksum,
+                        * tunnel TSO).
+                        *
+                        * PMDs should not use these fields unconditionally
+                        * when calculating offsets.
+                        *
+                        * Applications are expected to set appropriate tunnel
+                        * offload flags when they fill in these fields.
+                        */
                        uint64_t outer_l3_len:RTE_MBUF_OUTL3_LEN_BITS;
                        /**< Outer L3 (IP) Hdr Length. */
                        uint64_t outer_l2_len:RTE_MBUF_OUTL2_LEN_BITS;