[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>

10 files changed, 24 insertions, 26 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;
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 6db03ab7cec8..85f99f60deea 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -315,9 +315,10 @@ struct net_device
 #define NETIF_F_GSO_SHIFT       16
 #define NETIF_F_GSO_MASK        0xffff0000
 #define NETIF_F_TSO             (SKB_GSO_TCPV4 << NETIF_F_GSO_SHIFT)
-#define NETIF_F_UFO             (SKB_GSO_UDPV4 << NETIF_F_GSO_SHIFT)
+#define NETIF_F_UFO             (SKB_GSO_UDP << NETIF_F_GSO_SHIFT)
 #define NETIF_F_GSO_ROBUST      (SKB_GSO_DODGY << NETIF_F_GSO_SHIFT)
-#define NETIF_F_TSO_ECN         (SKB_GSO_TCPV4_ECN << NETIF_F_GSO_SHIFT)
+#define NETIF_F_TSO_ECN         (SKB_GSO_TCP_ECN << NETIF_F_GSO_SHIFT)
+#define NETIF_F_TSO6            (SKB_GSO_TCPV6 << NETIF_F_GSO_SHIFT)
 
 #define NETIF_F_GEN_CSUM        (NETIF_F_NO_CSUM | NETIF_F_HW_CSUM)
 #define NETIF_F_ALL_CSUM        (NETIF_F_IP_CSUM | NETIF_F_GEN_CSUM)
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 59918be91d0a..57d7d4965f9a 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -171,13 +171,15 @@ enum {
 
 enum {
         SKB_GSO_TCPV4 = 1 << 0,
-        SKB_GSO_UDPV4 = 1 << 1,
+        SKB_GSO_UDP = 1 << 1,
 
         /* This indicates the skb is from an untrusted source. */
         SKB_GSO_DODGY = 1 << 2,
 
         /* This indicates the tcp segment has CWR set. */
-        SKB_GSO_TCPV4_ECN = 1 << 3,
+        SKB_GSO_TCP_ECN = 1 << 3,
+
+        SKB_GSO_TCPV6 = 1 << 4,
 };
 
 /** 
diff --git a/include/net/ip6_route.h b/include/net/ip6_route.h
index a398ae5e30f9..ab29dafb1a6a 100644
--- a/include/net/ip6_route.h
+++ b/include/net/ip6_route.h
@@ -146,7 +146,7 @@ static inline void ip6_dst_store(struct sock *sk, struct dst_entry *dst,
         struct rt6_info *rt = (struct rt6_info *) dst;
 
         write_lock(&sk->sk_dst_lock);
-        __sk_dst_set(sk, dst);
+        sk_setup_caps(sk, dst);
         np->daddr_cache = daddr;
         np->dst_cookie = rt->rt6i_node ? rt->rt6i_node->fn_sernum : 0;
         write_unlock(&sk->sk_dst_lock);
diff --git a/include/net/tcp_ecn.h b/include/net/tcp_ecn.h
index 7bb366f70934..4629d77173f2 100644
--- a/include/net/tcp_ecn.h
+++ b/include/net/tcp_ecn.h
@@ -55,9 +55,7 @@ static inline void TCP_ECN_send(struct sock *sk, struct tcp_sock *tp,
                         if (tp->ecn_flags&TCP_ECN_QUEUE_CWR) {
                                 tp->ecn_flags &= ~TCP_ECN_QUEUE_CWR;
                                 skb->h.th->cwr = 1;
-                                if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4)
-                                        skb_shinfo(skb)->gso_type |=
-                                                SKB_GSO_TCPV4_ECN;
+                                skb_shinfo(skb)->gso_type |= SKB_GSO_TCP_ECN;
                         }
                 } else {
                         /* ACK or retransmitted segment: clear ECT|CE */
diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index 7624fd1d8f9f..243d2a763363 100644
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -744,7 +744,7 @@ static inline int ip_ufo_append_data(struct sock *sk,
         if (!err) {
                 /* specify the length of each IP datagram fragment*/
                 skb_shinfo(skb)->gso_size = mtu - fragheaderlen;
-                skb_shinfo(skb)->gso_type = SKB_GSO_UDPV4;
+                skb_shinfo(skb)->gso_type = SKB_GSO_UDP;
                 __skb_queue_tail(&sk->sk_write_queue, skb);
 
                 return 0;
@@ -1089,7 +1089,7 @@ ssize_t	ip_append_page(struct sock *sk, struct page *page,
         if ((sk->sk_protocol == IPPROTO_UDP) &&
             (rt->u.dst.dev->features & NETIF_F_UFO)) {
                 skb_shinfo(skb)->gso_size = mtu - fragheaderlen;
-                skb_shinfo(skb)->gso_type = SKB_GSO_UDPV4;
+                skb_shinfo(skb)->gso_type = SKB_GSO_UDP;
         }
 
 
diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c
index e19457fe4f6e..0f26073117a3 100644
--- a/net/ipv6/af_inet6.c
+++ b/net/ipv6/af_inet6.c
@@ -660,8 +660,6 @@ int inet6_sk_rebuild_header(struct sock *sk)
                 }
 
                 ip6_dst_store(sk, dst, NULL);
-                sk->sk_route_caps = dst->dev->features &
-                        ~(NETIF_F_IP_CSUM | NETIF_F_TSO);
         }
 
         return 0;
diff --git a/net/ipv6/inet6_connection_sock.c b/net/ipv6/inet6_connection_sock.c
index eb2865d5ae28..5624f373164d 100644
--- a/net/ipv6/inet6_connection_sock.c
+++ b/net/ipv6/inet6_connection_sock.c
@@ -187,8 +187,6 @@ int inet6_csk_xmit(struct sk_buff *skb, int ipfragok)
                 }
 
                 ip6_dst_store(sk, dst, NULL);
-                sk->sk_route_caps = dst->dev->features &
-                        ~(NETIF_F_IP_CSUM | NETIF_F_TSO);
         }
 
         skb->dst = dst_clone(dst);
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index abb94de33768..11007c75ae02 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -230,7 +230,7 @@ int ip6_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl,
         skb->priority = sk->sk_priority;
 
         mtu = dst_mtu(dst);
-        if ((skb->len <= mtu) || ipfragok) {
+        if ((skb->len <= mtu) || ipfragok || skb_shinfo(skb)->gso_size) {
                 IP6_INC_STATS(IPSTATS_MIB_OUTREQUESTS);
                 return NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, skb, NULL, dst->dev,
                                 dst_output);
@@ -835,7 +835,7 @@ static inline int ip6_ufo_append_data(struct sock *sk,
                 /* specify the length of each IP datagram fragment*/
                 skb_shinfo(skb)->gso_size = mtu - fragheaderlen - 
                                             sizeof(struct frag_hdr);
-                skb_shinfo(skb)->gso_type = SKB_GSO_UDPV4;
+                skb_shinfo(skb)->gso_type = SKB_GSO_UDP;
                 ipv6_select_ident(skb, &fhdr);
                 skb_shinfo(skb)->ip6_frag_id = fhdr.identification;
                 __skb_queue_tail(&sk->sk_write_queue, skb);
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index bf7f8c26c488..7ea5bea49aa9 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -270,9 +270,8 @@ static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
         ipv6_addr_copy(&np->saddr, saddr);
         inet->rcv_saddr = LOOPBACK4_IPV6;
 
+        sk->sk_gso_type = SKB_GSO_TCPV6;
         ip6_dst_store(sk, dst, NULL);
-        sk->sk_route_caps = dst->dev->features &
-                ~(NETIF_F_IP_CSUM | NETIF_F_TSO);
 
         icsk->icsk_ext_hdr_len = 0;
         if (np->opt)
@@ -930,9 +929,8 @@ static struct sock * tcp_v6_syn_recv_sock(struct sock *sk, struct sk_buff *skb,
          * comment in that function for the gory details. -acme
          */
 
+        sk->sk_gso_type = SKB_GSO_TCPV6;
         ip6_dst_store(newsk, dst, NULL);
-        newsk->sk_route_caps = dst->dev->features &
-                ~(NETIF_F_IP_CSUM | NETIF_F_TSO);
 
         newtcp6sk = (struct tcp6_sock *)newsk;
         inet_sk(newsk)->pinet6 = &newtcp6sk->inet6;