net/enic: support TSO

The enic TSO implementation requires that the length of the Eth/IP/TCP
headers be passed to the NIC. Other than that, it's just a matter of
setting the mss and offload mode on a per packet basis.

In TSO mode, IP and TCP checksums are offloaded even if not requested
with mb->ol_flags.

Signed-off-by: John Daley <johndale@cisco.com>

diff --git a/doc/guides/nics/features/enic.ini b/doc/guides/nics/features/enic.ini
index 86576a7..51b330f 100644 (file)
--- a/doc/guides/nics/features/enic.ini
+++ b/doc/guides/nics/features/enic.ini
@@ -10,6 +10,7 @@ Queue start/stop     = Y
 MTU update           = Y
 Jumbo frame          = Y
 Scattered Rx         = Y
+TSO                  = Y
 Promiscuous mode     = Y
 Unicast MAC filter   = Y
 Multicast MAC filter = Y

diff --git a/drivers/net/enic/enic_ethdev.c b/drivers/net/enic/enic_ethdev.c
index e5ceb98..c3ba2aa 100644 (file)
--- a/drivers/net/enic/enic_ethdev.c
+++ b/drivers/net/enic/enic_ethdev.c
@@ -475,7 +475,8 @@ static void enicpmd_dev_info_get(struct rte_eth_dev *eth_dev,
                DEV_TX_OFFLOAD_VLAN_INSERT |
                DEV_TX_OFFLOAD_IPV4_CKSUM  |
                DEV_TX_OFFLOAD_UDP_CKSUM   |
-               DEV_TX_OFFLOAD_TCP_CKSUM;
+               DEV_TX_OFFLOAD_TCP_CKSUM   |
+               DEV_TX_OFFLOAD_TCP_TSO;
        device_info->default_rxconf = (struct rte_eth_rxconf) {
                .rx_free_thresh = ENIC_DEFAULT_RX_FREE_THRESH
        };

diff --git a/drivers/net/enic/enic_rxtx.c b/drivers/net/enic/enic_rxtx.c
index f762a26..5d59d8f 100644 (file)
--- a/drivers/net/enic/enic_rxtx.c
+++ b/drivers/net/enic/enic_rxtx.c
@@ -37,6 +37,9 @@
 #include "enic_compat.h"
 #include "rq_enet_desc.h"
 #include "enic.h"
+#include <rte_ether.h>
+#include <rte_ip.h>
+#include <rte_tcp.h>
 
 #define RTE_PMD_USE_PREFETCH
 
@@ -129,6 +132,60 @@ enic_cq_rx_desc_n_bytes(struct cq_desc *cqd)
                CQ_ENET_RQ_DESC_BYTES_WRITTEN_MASK;
 }
 
+/* Find the offset to L5. This is needed by enic TSO implementation.
+ * Return 0 if not a TCP packet or can't figure out the length.
+ */
+static inline uint8_t tso_header_len(struct rte_mbuf *mbuf)
+{
+       struct ether_hdr *eh;
+       struct vlan_hdr *vh;
+       struct ipv4_hdr *ip4;
+       struct ipv6_hdr *ip6;
+       struct tcp_hdr *th;
+       uint8_t hdr_len;
+       uint16_t ether_type;
+
+       /* offset past Ethernet header */
+       eh = rte_pktmbuf_mtod(mbuf, struct ether_hdr *);
+       ether_type = eh->ether_type;
+       hdr_len = sizeof(struct ether_hdr);
+       if (ether_type == rte_cpu_to_be_16(ETHER_TYPE_VLAN)) {
+               vh = rte_pktmbuf_mtod_offset(mbuf, struct vlan_hdr *, hdr_len);
+               ether_type = vh->eth_proto;
+               hdr_len += sizeof(struct vlan_hdr);
+       }
+
+       /* offset past IP header */
+       switch (rte_be_to_cpu_16(ether_type)) {
+       case ETHER_TYPE_IPv4:
+               ip4 = rte_pktmbuf_mtod_offset(mbuf, struct ipv4_hdr *, hdr_len);
+               if (ip4->next_proto_id != IPPROTO_TCP)
+                       return 0;
+               hdr_len += (ip4->version_ihl & 0xf) * 4;
+               break;
+       case ETHER_TYPE_IPv6:
+               ip6 = rte_pktmbuf_mtod_offset(mbuf, struct ipv6_hdr *, hdr_len);
+               if (ip6->proto != IPPROTO_TCP)
+                       return 0;
+               hdr_len += sizeof(struct ipv6_hdr);
+               break;
+       default:
+               return 0;
+       }
+
+       if ((hdr_len + sizeof(struct tcp_hdr)) > mbuf->pkt_len)
+               return 0;
+
+       /* offset past TCP header */
+       th = rte_pktmbuf_mtod_offset(mbuf, struct tcp_hdr *, hdr_len);
+       hdr_len += (th->data_off >> 4) * 4;
+
+       if (hdr_len > mbuf->pkt_len)
+               return 0;
+
+       return hdr_len;
+}
+
 static inline uint8_t
 enic_cq_rx_check_err(struct cq_desc *cqd)
 {
@@ -466,6 +523,8 @@ uint16_t enic_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts,
        uint8_t vlan_tag_insert;
        uint8_t eop;
        uint64_t bus_addr;
+       uint8_t offload_mode;
+       uint16_t header_len;
 
        enic_cleanup_wq(enic, wq);
        wq_desc_avail = vnic_wq_desc_avail(wq);
@@ -497,13 +556,17 @@ uint16_t enic_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts,
                desc_p = descs + head_idx;
 
                eop = (data_len == pkt_len);
-
-               if (ol_flags & ol_flags_mask) {
-                       if (ol_flags & PKT_TX_VLAN_PKT) {
-                               vlan_tag_insert = 1;
-                               vlan_id = tx_pkt->vlan_tci;
+               offload_mode = WQ_ENET_OFFLOAD_MODE_CSUM;
+               header_len = 0;
+
+               if (tx_pkt->tso_segsz) {
+                       header_len = tso_header_len(tx_pkt);
+                       if (header_len) {
+                               offload_mode = WQ_ENET_OFFLOAD_MODE_TSO;
+                               mss = tx_pkt->tso_segsz;
                        }
-
+               }
+               if ((ol_flags & ol_flags_mask) && (header_len == 0)) {
                        if (ol_flags & PKT_TX_IP_CKSUM)
                                mss |= ENIC_CALC_IP_CKSUM;
 
@@ -516,8 +579,14 @@ uint16_t enic_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts,
                        }
                }
 
-               wq_enet_desc_enc(&desc_tmp, bus_addr, data_len, mss, 0, 0, eop,
-                                eop, 0, vlan_tag_insert, vlan_id, 0);
+               if (ol_flags & PKT_TX_VLAN_PKT) {
+                       vlan_tag_insert = 1;
+                       vlan_id = tx_pkt->vlan_tci;
+               }
+
+               wq_enet_desc_enc(&desc_tmp, bus_addr, data_len, mss, header_len,
+                                offload_mode, eop, eop, 0, vlan_tag_insert,
+                                vlan_id, 0);
 
                *desc_p = desc_tmp;
                buf = &wq->bufs[head_idx];
@@ -537,8 +606,9 @@ uint16_t enic_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts,
                                           + tx_pkt->data_off);
                                wq_enet_desc_enc((struct wq_enet_desc *)
                                                 &desc_tmp, bus_addr, data_len,
-                                                mss, 0, 0, eop, eop, 0,
-                                                vlan_tag_insert, vlan_id, 0);
+                                                mss, 0, offload_mode, eop, eop,
+                                                0, vlan_tag_insert, vlan_id,
+                                                0);
 
                                *desc_p = desc_tmp;
                                buf = &wq->bufs[head_idx];