1 files changed, 63 insertions, 26 deletions

diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 76b148b..2451aeb 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -661,6 +661,47 @@ struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp)
 	return NULL;
 }
 
+static unsigned int tcp_xmit_size_goal(struct sock *sk, u32 mss_now,
+				       int large_allowed)
+{
+	struct tcp_sock *tp = tcp_sk(sk);
+	u32 xmit_size_goal, old_size_goal;
+
+	xmit_size_goal = mss_now;
+
+	if (large_allowed && sk_can_gso(sk)) {
+		xmit_size_goal = ((sk->sk_gso_max_size - 1) -
+				  inet_csk(sk)->icsk_af_ops->net_header_len -
+				  inet_csk(sk)->icsk_ext_hdr_len -
+				  tp->tcp_header_len);
+
+		xmit_size_goal = tcp_bound_to_half_wnd(tp, xmit_size_goal);
+
+		/* We try hard to avoid divides here */
+		old_size_goal = tp->xmit_size_goal_segs * mss_now;
+
+		if (likely(old_size_goal <= xmit_size_goal &&
+			   old_size_goal + mss_now > xmit_size_goal)) {
+			xmit_size_goal = old_size_goal;
+		} else {
+			tp->xmit_size_goal_segs = xmit_size_goal / mss_now;
+			xmit_size_goal = tp->xmit_size_goal_segs * mss_now;
+		}
+	}
+
+	return max(xmit_size_goal, mss_now);
+}
+
+static int tcp_send_mss(struct sock *sk, int *size_goal, int flags)
+{
+	int mss_now;
+
+	mss_now = tcp_current_mss(sk);
+	*size_goal = tcp_xmit_size_goal(sk, mss_now, !(flags & MSG_OOB));
+
+	return mss_now;
+}
+
 static ssize_t do_tcp_sendpages(struct sock *sk, struct page **pages, int poffset,
 			 size_t psize, int flags)
 {
@@ -677,13 +718,12 @@ static ssize_t do_tcp_sendpages(struct sock *sk, struct page **pages, int poffse
 
 	clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
 
-	mss_now = tcp_current_mss(sk, !(flags&MSG_OOB));
-	size_goal = tp->xmit_size_goal;
+	mss_now = tcp_send_mss(sk, &size_goal, flags);
 	copied = 0;
 
 	err = -EPIPE;
 	if (sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN))
-		goto do_error;
+		goto out_err;
 
 	while (psize > 0) {
 		struct sk_buff *skb = tcp_write_queue_tail(sk);
@@ -761,8 +801,7 @@ wait_for_memory:
 		if ((err = sk_stream_wait_memory(sk, &timeo)) != 0)
 			goto do_error;
 
-		mss_now = tcp_current_mss(sk, !(flags&MSG_OOB));
-		size_goal = tp->xmit_size_goal;
+		mss_now = tcp_send_mss(sk, &size_goal, flags);
 	}
 
 out:
@@ -844,8 +883,7 @@ int tcp_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg,
 	/* This should be in poll */
 	clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
 
-	mss_now = tcp_current_mss(sk, !(flags&MSG_OOB));
-	size_goal = tp->xmit_size_goal;
+	mss_now = tcp_send_mss(sk, &size_goal, flags);
 
 	/* Ok commence sending. */
 	iovlen = msg->msg_iovlen;
@@ -854,7 +892,7 @@ int tcp_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg,
 
 	err = -EPIPE;
 	if (sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN))
-		goto do_error;
+		goto out_err;
 
 	while (--iovlen >= 0) {
 		int seglen = iov->iov_len;
@@ -1007,8 +1045,7 @@ wait_for_memory:
 			if ((err = sk_stream_wait_memory(sk, &timeo)) != 0)
 				goto do_error;
 
-			mss_now = tcp_current_mss(sk, !(flags&MSG_OOB));
-			size_goal = tp->xmit_size_goal;
+			mss_now = tcp_send_mss(sk, &size_goal, flags);
 		}
 	}
 
@@ -1045,8 +1082,7 @@ out_err:
  */
 
 static int tcp_recv_urg(struct sock *sk, long timeo,
-			struct msghdr *msg, int len, int flags,
-			int *addr_len)
+			struct msghdr *msg, int len, int flags)
 {
 	struct tcp_sock *tp = tcp_sk(sk);
 
@@ -1661,7 +1697,7 @@ out:
 	return err;
 
 recv_urg:
-	err = tcp_recv_urg(sk, timeo, msg, len, flags, addr_len);
+	err = tcp_recv_urg(sk, timeo, msg, len, flags);
 	goto out;
 }
 
@@ -2478,23 +2514,23 @@ struct sk_buff **tcp_gro_receive(struct sk_buff **head, struct sk_buff *skb)
 	struct tcphdr *th2;
 	unsigned int thlen;
 	unsigned int flags;
-	unsigned int total;
 	unsigned int mss = 1;
 	int flush = 1;
+	int i;
 
-	if (!pskb_may_pull(skb, sizeof(*th)))
+	th = skb_gro_header(skb, sizeof(*th));
+	if (unlikely(!th))
 		goto out;
 
-	th = tcp_hdr(skb);
 	thlen = th->doff * 4;
 	if (thlen < sizeof(*th))
 		goto out;
 
-	if (!pskb_may_pull(skb, thlen))
+	th = skb_gro_header(skb, thlen);
+	if (unlikely(!th))
 		goto out;
 
-	th = tcp_hdr(skb);
-	__skb_pull(skb, thlen);
+	skb_gro_pull(skb, thlen);
 
 	flags = tcp_flag_word(th);
 
@@ -2504,7 +2540,7 @@ struct sk_buff **tcp_gro_receive(struct sk_buff **head, struct sk_buff *skb)
 
 		th2 = tcp_hdr(p);
 
-		if (th->source != th2->source || th->dest != th2->dest) {
+		if ((th->source ^ th2->source) | (th->dest ^ th2->dest)) {
 			NAPI_GRO_CB(p)->same_flow = 0;
 			continue;
 		}
@@ -2519,14 +2555,15 @@ found:
 	flush |= flags & TCP_FLAG_CWR;
 	flush |= (flags ^ tcp_flag_word(th2)) &
 		  ~(TCP_FLAG_CWR | TCP_FLAG_FIN | TCP_FLAG_PSH);
-	flush |= th->ack_seq != th2->ack_seq || th->window != th2->window;
-	flush |= memcmp(th + 1, th2 + 1, thlen - sizeof(*th));
+	flush |= (th->ack_seq ^ th2->ack_seq) | (th->window ^ th2->window);
+	for (i = sizeof(*th); !flush && i < thlen; i += 4)
+		flush |= *(u32 *)((u8 *)th + i) ^
+			 *(u32 *)((u8 *)th2 + i);
 
-	total = p->len;
 	mss = skb_shinfo(p)->gso_size;
 
-	flush |= skb->len > mss || skb->len <= 0;
-	flush |= ntohl(th2->seq) + total != ntohl(th->seq);
+	flush |= (skb_gro_len(skb) > mss) | !skb_gro_len(skb);
+	flush |= (ntohl(th2->seq) + skb_gro_len(p)) ^ ntohl(th->seq);
 
 	if (flush || skb_gro_receive(head, skb)) {
 		mss = 1;
@@ -2538,7 +2575,7 @@ found:
 	tcp_flag_word(th2) |= flags & (TCP_FLAG_FIN | TCP_FLAG_PSH);
 
 out_check_final:
-	flush = skb->len < mss;
+	flush = skb_gro_len(skb) < mss;
 	flush |= flags & (TCP_FLAG_URG | TCP_FLAG_PSH | TCP_FLAG_RST |
 			  TCP_FLAG_SYN | TCP_FLAG_FIN);