mbuf: clarify outer offsets for non-tunnel packets

The default policy for offload-specific fields is that
they are undefined unless the corresponding offloads are
requested in mbuf ol_flags. This is also the case for outer
L2 and L3 length fields which must not be assumed to contain
zeros for non-tunnel packets. The patch clarifies this behaviour
in the comments and also adds appropriate checks to the PMDs which
do not check any tunnel-related offloads before using the said fields.

Signed-off-by: Ivan Malov <ivan.malov@oktetlabs.ru>
Reviewed-by: Andrew Rybchenko <arybchenko@solarflare.com>
Acked-by: Konstantin Ananyev <konstantin.ananyev@intel.com>
Acked-by: Olivier Matz <olivier.matz@6wind.com>

diff --git a/drivers/net/bnxt/bnxt_txr.c b/drivers/net/bnxt/bnxt_txr.c
index 124186e..c71e6f1 100644 (file)
--- a/drivers/net/bnxt/bnxt_txr.c
+++ b/drivers/net/bnxt/bnxt_txr.c
@@ -235,8 +235,10 @@ static uint16_t bnxt_start_xmit(struct rte_mbuf *tx_pkt,
                        txbd1->lflags |= TX_BD_LONG_LFLAGS_LSO |
                                         TX_BD_LONG_LFLAGS_T_IPID;
                        hdr_size = tx_pkt->l2_len + tx_pkt->l3_len +
-                                       tx_pkt->l4_len + tx_pkt->outer_l2_len +
-                                       tx_pkt->outer_l3_len;
+                                       tx_pkt->l4_len;
+                       hdr_size += (tx_pkt->ol_flags & PKT_TX_TUNNEL_MASK) ?
+                                   tx_pkt->outer_l2_len +
+                                   tx_pkt->outer_l3_len : 0;
                        /* The hdr_size is multiple of 16bit units not 8bit.
                         * Hence divide by 2.
                         */

diff --git a/drivers/net/fm10k/fm10k_rxtx.c b/drivers/net/fm10k/fm10k_rxtx.c
index 2f4dad0..5c31121 100644 (file)
--- a/drivers/net/fm10k/fm10k_rxtx.c
+++ b/drivers/net/fm10k/fm10k_rxtx.c
@@ -619,8 +619,9 @@ static inline void tx_xmit_pkt(struct fm10k_tx_queue *q, struct rte_mbuf *mb)
                        rte_cpu_to_le_16(rte_pktmbuf_data_len(mb));
 
        if (mb->ol_flags & PKT_TX_TCP_SEG) {
-               hdrlen = mb->outer_l2_len + mb->outer_l3_len + mb->l2_len +
-                       mb->l3_len + mb->l4_len;
+               hdrlen = mb->l2_len + mb->l3_len + mb->l4_len;
+               hdrlen += (mb->ol_flags & PKT_TX_TUNNEL_MASK) ?
+                         mb->outer_l2_len + mb->outer_l3_len : 0;
                if (q->hw_ring[q->next_free].flags & FM10K_TXD_FLAG_FTAG)
                        hdrlen += sizeof(struct fm10k_ftag);
 

diff --git a/drivers/net/i40e/i40e_rxtx.c b/drivers/net/i40e/i40e_rxtx.c
index 85c44f5..34aa6c8 100644 (file)
--- a/drivers/net/i40e/i40e_rxtx.c
+++ b/drivers/net/i40e/i40e_rxtx.c
@@ -981,15 +981,9 @@ i40e_set_tso_ctx(struct rte_mbuf *mbuf, union i40e_tx_offload tx_offload)
                return ctx_desc;
        }
 
-       /**
-        * in case of non tunneling packet, the outer_l2_len and
-        * outer_l3_len must be 0.
-        */
-       hdr_len = tx_offload.outer_l2_len +
-               tx_offload.outer_l3_len +
-               tx_offload.l2_len +
-               tx_offload.l3_len +
-               tx_offload.l4_len;
+       hdr_len = tx_offload.l2_len + tx_offload.l3_len + tx_offload.l4_len;
+       hdr_len += (mbuf->ol_flags & PKT_TX_TUNNEL_MASK) ?
+                  tx_offload.outer_l2_len + tx_offload.outer_l3_len : 0;
 
        cd_cmd = I40E_TX_CTX_DESC_TSO;
        cd_tso_len = mbuf->pkt_len - hdr_len;

diff --git a/drivers/net/iavf/iavf_rxtx.c b/drivers/net/iavf/iavf_rxtx.c
index 0be3ede..2d37c17 100644 (file)
--- a/drivers/net/iavf/iavf_rxtx.c
+++ b/drivers/net/iavf/iavf_rxtx.c
@@ -1449,9 +1449,6 @@ iavf_set_tso_ctx(struct rte_mbuf *mbuf, union iavf_tx_offload tx_offload)
                return ctx_desc;
        }
 
-       /* in case of non tunneling packet, the outer_l2_len and
-        * outer_l3_len must be 0.
-        */
        hdr_len = tx_offload.l2_len +
                  tx_offload.l3_len +
                  tx_offload.l4_len;

diff --git a/drivers/net/ice/ice_rxtx.c b/drivers/net/ice/ice_rxtx.c
index 0fb3e7f..035ed84 100644 (file)
--- a/drivers/net/ice/ice_rxtx.c
+++ b/drivers/net/ice/ice_rxtx.c
@@ -1940,15 +1940,9 @@ ice_set_tso_ctx(struct rte_mbuf *mbuf, union ice_tx_offload tx_offload)
                return ctx_desc;
        }
 
-       /**
-        * in case of non tunneling packet, the outer_l2_len and
-        * outer_l3_len must be 0.
-        */
-       hdr_len = tx_offload.outer_l2_len +
-                 tx_offload.outer_l3_len +
-                 tx_offload.l2_len +
-                 tx_offload.l3_len +
-                 tx_offload.l4_len;
+       hdr_len = tx_offload.l2_len + tx_offload.l3_len + tx_offload.l4_len;
+       hdr_len += (mbuf->ol_flags & PKT_TX_TUNNEL_MASK) ?
+                  tx_offload.outer_l2_len + tx_offload.outer_l3_len : 0;
 
        cd_cmd = ICE_TX_CTX_DESC_TSO;
        cd_tso_len = mbuf->pkt_len - hdr_len;

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;