[dpdk-dev] [PATCH v4 2/3] net/i40e: add TSO support on tunneling packet

[Jianfeng Tan]

To enable Tx side offload on tunneling packet, driver should set
correct tunneling parameters: (1) EIPT, External IP header type;
(2) EIPLEN, External IP; (3) L4TUNT; (4) L4TUNLEN. This parsing
behavior is based on (ol_flag & PKT_TX_TUNNEL_MASK). And when
it's a tunneling packet, MACLEN defines the outer L2 header.

Also, we define TSO on each kind of tunneling type as a capabilities.
Now only i40e declares to support them.

Signed-off-by: Zhe Tao <zhe.tao at intel.com>
Signed-off-by: Jianfeng Tan <jianfeng.tan at intel.com>
---
 drivers/net/i40e/i40e_ethdev.c |  6 ++-
 drivers/net/i40e/i40e_rxtx.c   | 90 +++++++++++++++++++++++++++++-------------
 lib/librte_ether/rte_ethdev.h  |  4 ++
 3 files changed, 72 insertions(+), 28 deletions(-)

diff --git a/drivers/net/i40e/i40e_ethdev.c b/drivers/net/i40e/i40e_ethdev.c
index d0aeb70..64ba570 100644
--- a/drivers/net/i40e/i40e_ethdev.c
+++ b/drivers/net/i40e/i40e_ethdev.c
@@ -2576,7 +2576,11 @@ i40e_dev_info_get(struct rte_eth_dev *dev, struct rte_eth_dev_info *dev_info)
 		DEV_TX_OFFLOAD_TCP_CKSUM |
 		DEV_TX_OFFLOAD_SCTP_CKSUM |
 		DEV_TX_OFFLOAD_OUTER_IPV4_CKSUM |
-		DEV_TX_OFFLOAD_TCP_TSO;
+		DEV_TX_OFFLOAD_TCP_TSO |
+		DEV_TX_OFFLOAD_VXLAN_TNL_TSO |
+		DEV_TX_OFFLOAD_GRE_TNL_TSO |
+		DEV_TX_OFFLOAD_IPIP_TNL_TSO |
+		DEV_TX_OFFLOAD_GENEVE_TNL_TSO;
 	dev_info->hash_key_size = (I40E_PFQF_HKEY_MAX_INDEX + 1) *
 						sizeof(uint32_t);
 	dev_info->reta_size = pf->hash_lut_size;
diff --git a/drivers/net/i40e/i40e_rxtx.c b/drivers/net/i40e/i40e_rxtx.c
index 554d167..4eac713 100644
--- a/drivers/net/i40e/i40e_rxtx.c
+++ b/drivers/net/i40e/i40e_rxtx.c
@@ -779,33 +779,65 @@ i40e_rxd_build_fdir(volatile union i40e_rx_desc *rxdp, struct rte_mbuf *mb)
 #endif
 	return flags;
 }
+
+static inline void
+i40e_parse_tunneling_params(uint64_t ol_flags,
+			    union i40e_tx_offload tx_offload,
+			    uint32_t *cd_tunneling)
+{
+	/* EIPT: External (outer) IP header type */
+	if (ol_flags & PKT_TX_OUTER_IP_CKSUM)
+		*cd_tunneling |= I40E_TX_CTX_EXT_IP_IPV4;
+	else if (ol_flags & PKT_TX_OUTER_IPV4)
+		*cd_tunneling |= I40E_TX_CTX_EXT_IP_IPV4_NO_CSUM;
+	else if (ol_flags & PKT_TX_OUTER_IPV6)
+		*cd_tunneling |= I40E_TX_CTX_EXT_IP_IPV6;
+
+	/* EIPLEN: External (outer) IP header length, in DWords */
+	*cd_tunneling |= (tx_offload.outer_l3_len >> 2) <<
+		I40E_TXD_CTX_QW0_EXT_IPLEN_SHIFT;
+
+	/* L4TUNT: L4 Tunneling Type */
+	switch (ol_flags & PKT_TX_TUNNEL_MASK) {
+	case PKT_TX_TUNNEL_IPIP:
+		/* for non UDP / GRE tunneling, set to 00b */
+		break;
+	case PKT_TX_TUNNEL_VXLAN:
+	case PKT_TX_TUNNEL_GENEVE:
+		*cd_tunneling |= I40E_TXD_CTX_UDP_TUNNELING;
+		break;
+	case PKT_TX_TUNNEL_GRE:
+		*cd_tunneling |= I40E_TXD_CTX_GRE_TUNNELING;
+		break;
+	default:
+		PMD_TX_LOG(ERR, "Tunnel type not supported\n");
+		return;
+	}
+
+	/* L4TUNLEN: L4 Tunneling Length, in Words
+	 *
+	 * We depend on app to set rte_mbuf.l2_len correctly.
+	 * For IP in GRE it should be set to the length of the GRE
+	 * header;
+	 * for MAC in GRE or MAC in UDP it should be set to the length
+	 * of the GRE or UDP headers plus the inner MAC up to including
+	 * its last Ethertype.
+	 */
+	*cd_tunneling |= (tx_offload.l2_len >> 1) <<
+		I40E_TXD_CTX_QW0_NATLEN_SHIFT;
+}
+
 static inline void
 i40e_txd_enable_checksum(uint64_t ol_flags,
 			uint32_t *td_cmd,
 			uint32_t *td_offset,
-			union i40e_tx_offload tx_offload,
-			uint32_t *cd_tunneling)
+			union i40e_tx_offload tx_offload)
 {
-	/* UDP tunneling packet TX checksum offload */
-	if (ol_flags & PKT_TX_OUTER_IP_CKSUM) {
-
+	/* Set MACLEN */
+	if (ol_flags & PKT_TX_TUNNEL_MASK)
 		*td_offset |= (tx_offload.outer_l2_len >> 1)
 				<< I40E_TX_DESC_LENGTH_MACLEN_SHIFT;
-
-		if (ol_flags & PKT_TX_OUTER_IP_CKSUM)
-			*cd_tunneling |= I40E_TX_CTX_EXT_IP_IPV4;
-		else if (ol_flags & PKT_TX_OUTER_IPV4)
-			*cd_tunneling |= I40E_TX_CTX_EXT_IP_IPV4_NO_CSUM;
-		else if (ol_flags & PKT_TX_OUTER_IPV6)
-			*cd_tunneling |= I40E_TX_CTX_EXT_IP_IPV6;
-
-		/* Now set the ctx descriptor fields */
-		*cd_tunneling |= (tx_offload.outer_l3_len >> 2) <<
-				I40E_TXD_CTX_QW0_EXT_IPLEN_SHIFT |
-				(tx_offload.l2_len >> 1) <<
-				I40E_TXD_CTX_QW0_NATLEN_SHIFT;
-
-	} else
+	else
 		*td_offset |= (tx_offload.l2_len >> 1)
 			<< I40E_TX_DESC_LENGTH_MACLEN_SHIFT;
 
@@ -1484,7 +1516,8 @@ i40e_calc_context_desc(uint64_t flags)
 {
 	static uint64_t mask = PKT_TX_OUTER_IP_CKSUM |
 		PKT_TX_TCP_SEG |
-		PKT_TX_QINQ_PKT;
+		PKT_TX_QINQ_PKT |
+		PKT_TX_TUNNEL_MASK;
 
 #ifdef RTE_LIBRTE_IEEE1588
 	mask |= PKT_TX_IEEE1588_TMST;
@@ -1506,7 +1539,7 @@ i40e_set_tso_ctx(struct rte_mbuf *mbuf, union i40e_tx_offload tx_offload)
 	}
 
 	/**
-	 * in case of tunneling packet, the outer_l2_len and
+	 * in case of non tunneling packet, the outer_l2_len and
 	 * outer_l3_len must be 0.
 	 */
 	hdr_len = tx_offload.outer_l2_len +
@@ -1623,12 +1656,15 @@ i40e_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts, uint16_t nb_pkts)
 		/* Always enable CRC offload insertion */
 		td_cmd |= I40E_TX_DESC_CMD_ICRC;
 
-		/* Enable checksum offloading */
+		/* Fill in tunneling parameters if necessary */
 		cd_tunneling_params = 0;
-		if (ol_flags & I40E_TX_CKSUM_OFFLOAD_MASK) {
-			i40e_txd_enable_checksum(ol_flags, &td_cmd, &td_offset,
-				tx_offload, &cd_tunneling_params);
-		}
+		if (ol_flags & PKT_TX_TUNNEL_MASK)
+			i40e_parse_tunneling_params(ol_flags, tx_offload,
+						    &cd_tunneling_params);
+		/* Enable checksum offloading */
+		if (ol_flags & I40E_TX_CKSUM_OFFLOAD_MASK)
+			i40e_txd_enable_checksum(ol_flags, &td_cmd,
+						 &td_offset, tx_offload);
 
 		if (nb_ctx) {
 			/* Setup TX context descriptor if required */
diff --git a/lib/librte_ether/rte_ethdev.h b/lib/librte_ether/rte_ethdev.h
index b0fe033..7bf0cc4 100644
--- a/lib/librte_ether/rte_ethdev.h
+++ b/lib/librte_ether/rte_ethdev.h
@@ -864,6 +864,10 @@ struct rte_eth_conf {
 #define DEV_TX_OFFLOAD_UDP_TSO     0x00000040
 #define DEV_TX_OFFLOAD_OUTER_IPV4_CKSUM 0x00000080 /**< Used for tunneling packet. */
 #define DEV_TX_OFFLOAD_QINQ_INSERT 0x00000100
+#define DEV_TX_OFFLOAD_VXLAN_TNL_TSO    0x00000200    /**< Used for tunneling packet. */
+#define DEV_TX_OFFLOAD_GRE_TNL_TSO      0x00000400    /**< Used for tunneling packet. */
+#define DEV_TX_OFFLOAD_IPIP_TNL_TSO     0x00000800    /**< Used for tunneling packet. */
+#define DEV_TX_OFFLOAD_GENEVE_TNL_TSO   0x00001000    /**< Used for tunneling packet. */
 
 /**
  * Ethernet device information
-- 
2.7.4