[TCP]: Introduce tcp_wnd_end() to reduce line lengths

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/tcp.h b/include/net/tcp.h
index 76286e8..6a732d4 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -785,6 +785,12 @@
 	return 3;
 }
 
+/* Returns end sequence number of the receiver's advertised window */
+static inline u32 tcp_wnd_end(const struct tcp_sock *tp)
+{
+	return tp->snd_una + tp->snd_wnd;
+}
+
 /* RFC2861 Check whether we are limited by application or congestion window
  * This is the inverse of cwnd check in tcp_tso_should_defer
  */
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 41f4b86..366f63a 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -2921,8 +2921,7 @@
 
 	/* Was it a usable window open? */
 
-	if (!after(TCP_SKB_CB(tcp_send_head(sk))->end_seq,
-		   tp->snd_una + tp->snd_wnd)) {
+	if (!after(TCP_SKB_CB(tcp_send_head(sk))->end_seq, tcp_wnd_end(tp))) {
 		icsk->icsk_backoff = 0;
 		inet_csk_clear_xmit_timer(sk, ICSK_TIME_PROBE0);
 		/* Socket must be waked up by subsequent tcp_data_snd_check().
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index 1ca638b..821fae2 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -89,10 +89,10 @@
 {
 	struct tcp_sock *tp = tcp_sk(sk);
 
-	if (!before(tp->snd_una+tp->snd_wnd, tp->snd_nxt))
+	if (!before(tcp_wnd_end(tp), tp->snd_nxt))
 		return tp->snd_nxt;
 	else
-		return tp->snd_una+tp->snd_wnd;
+		return tcp_wnd_end(tp);
 }
 
 /* Calculate mss to advertise in SYN segment.
@@ -1024,7 +1024,7 @@
 	struct tcp_sock *tp = tcp_sk(sk);
 	u32 needed, window, cwnd_len;
 
-	window = (tp->snd_una + tp->snd_wnd - TCP_SKB_CB(skb)->seq);
+	window = tcp_wnd_end(tp) - TCP_SKB_CB(skb)->seq;
 	cwnd_len = mss_now * cwnd;
 
 	if (likely(cwnd_len <= window && skb != tcp_write_queue_tail(sk)))
@@ -1134,7 +1134,7 @@
 	if (skb->len > cur_mss)
 		end_seq = TCP_SKB_CB(skb)->seq + cur_mss;
 
-	return !after(end_seq, tp->snd_una + tp->snd_wnd);
+	return !after(end_seq, tcp_wnd_end(tp));
 }
 
 /* This checks if the data bearing packet SKB (usually tcp_send_head(sk))
@@ -1251,7 +1251,7 @@
 	BUG_ON(tcp_skb_pcount(skb) <= 1 ||
 	       (tp->snd_cwnd <= in_flight));
 
-	send_win = (tp->snd_una + tp->snd_wnd) - TCP_SKB_CB(skb)->seq;
+	send_win = tcp_wnd_end(tp) - TCP_SKB_CB(skb)->seq;
 
 	/* From in_flight test above, we know that cwnd > in_flight.  */
 	cong_win = (tp->snd_cwnd - in_flight) * tp->mss_cache;
@@ -1332,7 +1332,7 @@
 
 	if (tp->snd_wnd < size_needed)
 		return -1;
-	if (after(tp->snd_nxt + size_needed, tp->snd_una + tp->snd_wnd))
+	if (after(tp->snd_nxt + size_needed, tcp_wnd_end(tp)))
 		return 0;
 
 	/* Do we need to wait to drain cwnd? With none in flight, don't stall */
@@ -1687,7 +1687,7 @@
 			return;
 
 		/* Next skb is out of window. */
-		if (after(TCP_SKB_CB(next_skb)->end_seq, tp->snd_una+tp->snd_wnd))
+		if (after(TCP_SKB_CB(next_skb)->end_seq, tcp_wnd_end(tp)))
 			return;
 
 		/* Punt if not enough space exists in the first SKB for
@@ -1831,7 +1831,7 @@
 	 * case, when window is shrunk to zero. In this case
 	 * our retransmit serves as a zero window probe.
 	 */
-	if (!before(TCP_SKB_CB(skb)->seq, tp->snd_una+tp->snd_wnd)
+	if (!before(TCP_SKB_CB(skb)->seq, tcp_wnd_end(tp))
 	    && TCP_SKB_CB(skb)->seq != tp->snd_una)
 		return -EAGAIN;
 
@@ -2497,10 +2497,10 @@
 		struct sk_buff *skb;
 
 		if ((skb = tcp_send_head(sk)) != NULL &&
-		    before(TCP_SKB_CB(skb)->seq, tp->snd_una+tp->snd_wnd)) {
+		    before(TCP_SKB_CB(skb)->seq, tcp_wnd_end(tp))) {
 			int err;
 			unsigned int mss = tcp_current_mss(sk, 0);
-			unsigned int seg_size = tp->snd_una+tp->snd_wnd-TCP_SKB_CB(skb)->seq;
+			unsigned int seg_size = tcp_wnd_end(tp) - TCP_SKB_CB(skb)->seq;
 
 			if (before(tp->pushed_seq, TCP_SKB_CB(skb)->end_seq))
 				tp->pushed_seq = TCP_SKB_CB(skb)->end_seq;