[PATCH V2 5/6] Drivers: net: hyperv: Enable send side checksum offload

[K. Y. Srinivasan]

Enable send side checksum offload.

Signed-off-by: K. Y. Srinivasan <k...@microsoft.com>
Reviewed-by: Haiyang Zhang <haiya...@microsoft.com>
---
 drivers/net/hyperv/hyperv_net.h |   10 ++++++
 drivers/net/hyperv/netvsc_drv.c |   69 +++++++++++++++++++++++++++++++++++++-
 2 files changed, 77 insertions(+), 2 deletions(-)

diff --git a/drivers/net/hyperv/hyperv_net.h b/drivers/net/hyperv/hyperv_net.h
index faeb746..4cf2382 100644
--- a/drivers/net/hyperv/hyperv_net.h
+++ b/drivers/net/hyperv/hyperv_net.h
@@ -1035,6 +1035,16 @@ struct rndis_message {
 #define NDIS_PACKET_TYPE_FUNCTIONAL    0x00000400
 #define NDIS_PACKET_TYPE_MAC_FRAME     0x00000800
 
+#define INFO_IPV4       2
+#define INFO_IPV6       4
+#define INFO_TCP        2
+#define INFO_UDP        4
+
+#define TRANSPORT_INFO_NOT_IP   0
+#define TRANSPORT_INFO_IPV4_TCP ((INFO_IPV4 << 16) | INFO_TCP)
+#define TRANSPORT_INFO_IPV4_UDP ((INFO_IPV4 << 16) | INFO_UDP)
+#define TRANSPORT_INFO_IPV6_TCP ((INFO_IPV6 << 16) | INFO_TCP)
+#define TRANSPORT_INFO_IPV6_UDP ((INFO_IPV6 << 16) | INFO_UDP)
 
 
 #endif /* _HYPERV_NET_H */
diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
index 467bb3c..affee1b 100644
--- a/drivers/net/hyperv/netvsc_drv.c
+++ b/drivers/net/hyperv/netvsc_drv.c
@@ -257,6 +257,35 @@ static int netvsc_get_slots(struct sk_buff *skb)
        return slots + frag_slots;
 }
 
+static u32 get_net_transport_info(struct sk_buff *skb, u32 *trans_off)
+{
+       u32 ret_val = TRANSPORT_INFO_NOT_IP;
+
+       if ((eth_hdr(skb)->h_proto != htons(ETH_P_IP)) &&
+               (eth_hdr(skb)->h_proto != htons(ETH_P_IPV6))) {
+               goto not_ip;
+       }
+
+       *trans_off = skb_transport_offset(skb);
+
+       if ((eth_hdr(skb)->h_proto == htons(ETH_P_IP))) {
+               struct iphdr *iphdr = ip_hdr(skb);
+
+               if (iphdr->protocol == IPPROTO_TCP)
+                       ret_val = TRANSPORT_INFO_IPV4_TCP;
+               else if (iphdr->protocol == IPPROTO_UDP)
+                       ret_val = TRANSPORT_INFO_IPV4_UDP;
+       } else {
+               if (ipv6_hdr(skb)->nexthdr == IPPROTO_TCP)
+                       ret_val = TRANSPORT_INFO_IPV6_TCP;
+               else if (ipv6_hdr(skb)->nexthdr == IPPROTO_UDP)
+                       ret_val = TRANSPORT_INFO_IPV6_UDP;
+       }
+
+not_ip:
+       return ret_val;
+}
+
 static int netvsc_start_xmit(struct sk_buff *skb, struct net_device *net)
 {
        struct net_device_context *net_device_ctx = netdev_priv(net);
@@ -268,6 +297,10 @@ static int netvsc_start_xmit(struct sk_buff *skb, struct 
net_device *net)
        u32 rndis_msg_size;
        bool isvlan;
        struct rndis_per_packet_info *ppi;
+       struct ndis_tcp_ip_checksum_info *csum_info;
+       int  hdr_offset;
+       u32 net_trans_info;
+
 
        /* We will atmost need two pages to describe the rndis
         * header. We can only transmit MAX_PAGE_BUFFER_COUNT number
@@ -335,6 +368,37 @@ static int netvsc_start_xmit(struct sk_buff *skb, struct 
net_device *net)
                                VLAN_PRIO_SHIFT;
        }
 
+       net_trans_info = get_net_transport_info(skb, &hdr_offset);
+       if (net_trans_info == TRANSPORT_INFO_NOT_IP)
+               goto do_send;
+
+       /*
+        * Setup the sendside checksum offload only if this is not a
+        * GSO packet.
+        */
+       if (skb_is_gso(skb))
+               goto do_send;
+
+       rndis_msg_size += NDIS_CSUM_PPI_SIZE;
+       ppi = init_ppi_data(rndis_msg, NDIS_CSUM_PPI_SIZE,
+                           TCPIP_CHKSUM_PKTINFO);
+
+       csum_info = (struct ndis_tcp_ip_checksum_info *)((void *)ppi +
+                       ppi->ppi_offset);
+
+       if (net_trans_info & (INFO_IPV4 << 16))
+               csum_info->transmit.is_ipv4 = 1;
+       else
+               csum_info->transmit.is_ipv6 = 1;
+
+       if (net_trans_info & INFO_TCP) {
+               csum_info->transmit.tcp_checksum = 1;
+               csum_info->transmit.tcp_header_offset = hdr_offset;
+       } else if (net_trans_info & INFO_UDP) {
+               csum_info->transmit.udp_checksum = 1;
+       }
+
+do_send:
        /* Start filling in the page buffers with the rndis hdr */
        rndis_msg->msg_len += rndis_msg_size;
        packet->page_buf_cnt = init_page_array(rndis_msg, rndis_msg_size,
@@ -589,8 +653,9 @@ static int netvsc_probe(struct hv_device *dev,
        net->netdev_ops = &device_ops;
 
        /* TODO: Add GSO and Checksum offload */
-       net->hw_features = NETIF_F_RXCSUM | NETIF_F_SG;
-       net->features = NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_SG | NETIF_F_RXCSUM;
+       net->hw_features = NETIF_F_RXCSUM | NETIF_F_SG | NETIF_F_IP_CSUM;
+       net->features = NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_SG | NETIF_F_RXCSUM |
+                       NETIF_F_IP_CSUM;
 
        SET_ETHTOOL_OPS(net, &ethtool_ops);
        SET_NETDEV_DEV(net, &dev->device);
-- 
1.7.4.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/