[RFC PATCH 2/2] ixgbevf: Add support for UDP segmentation offload

[Alexander Duyck]

From: Alexander Duyck <alexander.h.du...@intel.com>

This patch adds support for UDP segmentation offload. Relatively few
changes were needed to add this support as it functions much like the TCP
segmentation offload.

Signed-off-by: Alexander Duyck <alexander.h.du...@intel.com>
---
 drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c |   25 ++++++++++++++++-----
 1 file changed, 19 insertions(+), 6 deletions(-)

diff --git a/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c 
b/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c
index 9a939dcaf727..c2986142c98a 100644
--- a/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c
+++ b/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c
@@ -3709,6 +3709,7 @@ static int ixgbevf_tso(struct ixgbevf_ring *tx_ring,
        } ip;
        union {
                struct tcphdr *tcp;
+               struct udphdr *udp;
                unsigned char *hdr;
        } l4;
        u32 paylen, l4_offset;
@@ -3731,7 +3732,8 @@ static int ixgbevf_tso(struct ixgbevf_ring *tx_ring,
        l4.hdr = skb_checksum_start(skb);
 
        /* ADV DTYP TUCMD MKRLOC/ISCSIHEDLEN */
-       type_tucmd = IXGBE_ADVTXD_TUCMD_L4T_TCP;
+       type_tucmd = (skb->csum_offset == offsetof(struct tcphdr, check)) ?
+                    IXGBE_ADVTXD_TUCMD_L4T_TCP : IXGBE_ADVTXD_TUCMD_L4T_UDP;
 
        /* initialize outer IP header fields */
        if (ip.v4->version == 4) {
@@ -3759,12 +3761,20 @@ static int ixgbevf_tso(struct ixgbevf_ring *tx_ring,
        /* determine offset of inner transport header */
        l4_offset = l4.hdr - skb->data;
 
-       /* compute length of segmentation header */
-       *hdr_len = (l4.tcp->doff * 4) + l4_offset;
-
        /* remove payload length from inner checksum */
        paylen = skb->len - l4_offset;
-       csum_replace_by_diff(&l4.tcp->check, htonl(paylen));
+
+       if (type_tucmd & IXGBE_ADVTXD_TUCMD_L4T_TCP) {
+               /* compute length of segmentation header */
+               *hdr_len = (l4.tcp->doff * 4) + l4_offset;
+               csum_replace_by_diff(&l4.tcp->check,
+                                    (__force __wsum)htonl(paylen));
+       } else {
+               /* compute length of segmentation header */
+               *hdr_len = sizeof(*l4.udp) + l4_offset;
+               csum_replace_by_diff(&l4.udp->check,
+                                    (__force __wsum)htonl(paylen));
+       }
 
        /* update gso size and bytecount with header size */
        first->gso_segs = skb_shinfo(skb)->gso_segs;
@@ -4368,6 +4378,7 @@ static void ixgbevf_get_stats(struct net_device *netdev,
        if (unlikely(mac_hdr_len > IXGBEVF_MAX_MAC_HDR_LEN))
                return features & ~(NETIF_F_HW_CSUM |
                                    NETIF_F_SCTP_CRC |
+                                   NETIF_F_GSO_UDP_L4 |
                                    NETIF_F_HW_VLAN_CTAG_TX |
                                    NETIF_F_TSO |
                                    NETIF_F_TSO6);
@@ -4376,6 +4387,7 @@ static void ixgbevf_get_stats(struct net_device *netdev,
        if (unlikely(network_hdr_len >  IXGBEVF_MAX_NETWORK_HDR_LEN))
                return features & ~(NETIF_F_HW_CSUM |
                                    NETIF_F_SCTP_CRC |
+                                   NETIF_F_GSO_UDP_L4 |
                                    NETIF_F_TSO |
                                    NETIF_F_TSO6);
 
@@ -4571,7 +4583,8 @@ static int ixgbevf_probe(struct pci_dev *pdev, const 
struct pci_device_id *ent)
                              NETIF_F_TSO6 |
                              NETIF_F_RXCSUM |
                              NETIF_F_HW_CSUM |
-                             NETIF_F_SCTP_CRC;
+                             NETIF_F_SCTP_CRC |
+                             NETIF_F_GSO_UDP_L4;
 
 #define IXGBEVF_GSO_PARTIAL_FEATURES (NETIF_F_GSO_GRE | \
                                      NETIF_F_GSO_GRE_CSUM | \