[IPV6]: Added GSO support for TCPv6

This patch adds GSO support for IPv6 and TCPv6.  This is based on a patch
by Ananda Raju <Ananda.Raju@neterion.com>.  His original description is:

	This patch enables TSO over IPv6. Currently Linux network stacks
	restricts TSO over IPv6 by clearing of the NETIF_F_TSO bit from
	"dev->features". This patch will remove this restriction.

	This patch will introduce a new flag NETIF_F_TSO6 which will be used
	to check whether device supports TSO over IPv6. If device support TSO
	over IPv6 then we don't clear of NETIF_F_TSO and which will make the
	TCP layer to create TSO packets. Any device supporting TSO over IPv6
	will set NETIF_F_TSO6 flag in "dev->features" along with NETIF_F_TSO.

	In case when user disables TSO using ethtool, NETIF_F_TSO will get
	cleared from "dev->features". So even if we have NETIF_F_TSO6 we don't
	get TSO packets created by TCP layer.

	SKB_GSO_TCPV4 renamed to SKB_GSO_TCP to make it generic GSO packet.
	SKB_GSO_UDPV4 renamed to SKB_GSO_UDP as UFO is not a IPv4 feature.
	UFO is supported over IPv6 also

	The following table shows there is significant improvement in
	throughput with normal frames and CPU usage for both normal and jumbo.

	--------------------------------------------------
	|          |     1500        |      9600         |
	|          ------------------|-------------------|
	|          | thru     CPU    |  thru     CPU     |
	--------------------------------------------------
	| TSO OFF  | 2.00   5.5% id  |  5.66   20.0% id  |
	--------------------------------------------------
	| TSO ON   | 2.63   78.0 id  |  5.67   39.0% id  |
	--------------------------------------------------

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 9 insertions, 6 deletions

diff --git a/drivers/net/s2io.c b/drivers/net/s2io.c
index 3defe5d4f7d3..74764694c64f 100644
--- a/drivers/net/s2io.c
+++ b/drivers/net/s2io.c
@@ -3960,7 +3960,7 @@ static int s2io_xmit(struct sk_buff *skb, struct net_device *dev)
         txdp->Control_2 = 0;
 #ifdef NETIF_F_TSO
         mss = skb_shinfo(skb)->gso_size;
-        if (skb_shinfo(skb)->gso_type == SKB_GSO_TCPV4) {
+        if (skb_shinfo(skb)->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6)) {
                 txdp->Control_1 |= TXD_TCP_LSO_EN;
                 txdp->Control_1 |= TXD_TCP_LSO_MSS(mss);
         }
@@ -3980,7 +3980,7 @@ static int s2io_xmit(struct sk_buff *skb, struct net_device *dev)
         }
 
         frg_len = skb->len - skb->data_len;
-        if (skb_shinfo(skb)->gso_type == SKB_GSO_UDPV4) {
+        if (skb_shinfo(skb)->gso_type == SKB_GSO_UDP) {
                 int ufo_size;
 
                 ufo_size = skb_shinfo(skb)->gso_size;
@@ -4009,7 +4009,7 @@ static int s2io_xmit(struct sk_buff *skb, struct net_device *dev)
         txdp->Host_Control = (unsigned long) skb;
         txdp->Control_1 |= TXD_BUFFER0_SIZE(frg_len);
 
-        if (skb_shinfo(skb)->gso_type == SKB_GSO_UDPV4)
+        if (skb_shinfo(skb)->gso_type == SKB_GSO_UDP)
                 txdp->Control_1 |= TXD_UFO_EN;
 
         frg_cnt = skb_shinfo(skb)->nr_frags;
@@ -4024,12 +4024,12 @@ static int s2io_xmit(struct sk_buff *skb, struct net_device *dev)
                     (sp->pdev, frag->page, frag->page_offset,
                      frag->size, PCI_DMA_TODEVICE);
                 txdp->Control_1 = TXD_BUFFER0_SIZE(frag->size);
-                if (skb_shinfo(skb)->gso_type == SKB_GSO_UDPV4)
+                if (skb_shinfo(skb)->gso_type == SKB_GSO_UDP)
                         txdp->Control_1 |= TXD_UFO_EN;
         }
         txdp->Control_1 |= TXD_GATHER_CODE_LAST;
 
-        if (skb_shinfo(skb)->gso_type == SKB_GSO_UDPV4)
+        if (skb_shinfo(skb)->gso_type == SKB_GSO_UDP)
                 frg_cnt++; /* as Txd0 was used for inband header */
 
         tx_fifo = mac_control->tx_FIFO_start[queue];
@@ -4043,7 +4043,7 @@ static int s2io_xmit(struct sk_buff *skb, struct net_device *dev)
         if (mss)
                 val64 |= TX_FIFO_SPECIAL_FUNC;
 #endif
-        if (skb_shinfo(skb)->gso_type == SKB_GSO_UDPV4)
+        if (skb_shinfo(skb)->gso_type == SKB_GSO_UDP)
                 val64 |= TX_FIFO_SPECIAL_FUNC;
         writeq(val64, &tx_fifo->List_Control);
 
@@ -7021,6 +7021,9 @@ s2io_init_nic(struct pci_dev *pdev, const struct pci_device_id *pre)
 #ifdef NETIF_F_TSO
         dev->features |= NETIF_F_TSO;
 #endif
+#ifdef NETIF_F_TSO6
+        dev->features |= NETIF_F_TSO6;
+#endif
         if (sp->device_type & XFRAME_II_DEVICE) {
                 dev->features |= NETIF_F_UFO;
                 dev->features |= NETIF_F_HW_CSUM;