tcp: unify tcp flag macros

unify tcp flag macros: TCPHDR_FIN, TCPHDR_SYN, TCPHDR_RST, TCPHDR_PSH,
TCPHDR_ACK, TCPHDR_URG, TCPHDR_ECE and TCPHDR_CWR. TCBCB_FLAG_* are replaced
with the corresponding TCPHDR_*.

Signed-off-by: Changli Gao <xiaosuo@gmail.com>
----
 include/net/tcp.h                      |   24 ++++++-------
 net/ipv4/tcp.c                         |    8 ++--
 net/ipv4/tcp_input.c                   |    2 -
 net/ipv4/tcp_output.c                  |   59 ++++++++++++++++-----------------
 net/netfilter/nf_conntrack_proto_tcp.c |   32 ++++++-----------
 net/netfilter/xt_TCPMSS.c              |    4 --
 6 files changed, 58 insertions(+), 71 deletions(-)
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index b4ed957..51d316d 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -294,9 +294,9 @@
 /* Packet ECN state for a SYN-ACK */
 static inline void TCP_ECN_send_synack(struct tcp_sock *tp, struct sk_buff *skb)
 {
-	TCP_SKB_CB(skb)->flags &= ~TCPCB_FLAG_CWR;
+	TCP_SKB_CB(skb)->flags &= ~TCPHDR_CWR;
 	if (!(tp->ecn_flags & TCP_ECN_OK))
-		TCP_SKB_CB(skb)->flags &= ~TCPCB_FLAG_ECE;
+		TCP_SKB_CB(skb)->flags &= ~TCPHDR_ECE;
 }
 
 /* Packet ECN state for a SYN.  */
@@ -306,7 +306,7 @@
 
 	tp->ecn_flags = 0;
 	if (sysctl_tcp_ecn == 1) {
-		TCP_SKB_CB(skb)->flags |= TCPCB_FLAG_ECE | TCPCB_FLAG_CWR;
+		TCP_SKB_CB(skb)->flags |= TCPHDR_ECE | TCPHDR_CWR;
 		tp->ecn_flags = TCP_ECN_OK;
 	}
 }
@@ -361,7 +361,7 @@
 	skb_shinfo(skb)->gso_type = 0;
 
 	TCP_SKB_CB(skb)->seq = seq;
-	if (flags & (TCPCB_FLAG_SYN | TCPCB_FLAG_FIN))
+	if (flags & (TCPHDR_SYN | TCPHDR_FIN))
 		seq++;
 	TCP_SKB_CB(skb)->end_seq = seq;
 }
@@ -820,7 +820,7 @@
 	tcb = TCP_SKB_CB(skb);
 	memset(&opts, 0, sizeof(opts));
 
-	if (unlikely(tcb->flags & TCPCB_FLAG_SYN))
+	if (unlikely(tcb->flags & TCPHDR_SYN))
 		tcp_options_size = tcp_syn_options(sk, skb, &opts, &md5);
 	else
 		tcp_options_size = tcp_established_options(sk, skb, &opts,
@@ -843,7 +843,7 @@
 	*(((__be16 *)th) + 6)	= htons(((tcp_header_size >> 2) << 12) |
 					tcb->flags);
 
-	if (unlikely(tcb->flags & TCPCB_FLAG_SYN)) {
+	if (unlikely(tcb->flags & TCPHDR_SYN)) {
 		/* RFC1323: The window in SYN & SYN/ACK segments
 		 * is never scaled.
 		 */
@@ -866,7 +866,7 @@
 	}
 
 	tcp_options_write((__be32 *)(th + 1), tp, &opts);
-	if (likely((tcb->flags & TCPCB_FLAG_SYN) == 0))
+	if (likely((tcb->flags & TCPHDR_SYN) == 0))
 		TCP_ECN_send(sk, skb, tcp_header_size);
 
 #ifdef CONFIG_TCP_MD5SIG
@@ -880,7 +880,7 @@
 
 	icsk->icsk_af_ops->send_check(sk, skb);
 
-	if (likely(tcb->flags & TCPCB_FLAG_ACK))
+	if (likely(tcb->flags & TCPHDR_ACK))
 		tcp_event_ack_sent(sk, tcp_skb_pcount(skb));
 
 	if (skb->len != tcp_header_size)
@@ -1023,7 +1023,7 @@
 
 	/* PSH and FIN should only be set in the second packet. */
 	flags = TCP_SKB_CB(skb)->flags;
-	TCP_SKB_CB(skb)->flags = flags & ~(TCPCB_FLAG_FIN | TCPCB_FLAG_PSH);
+	TCP_SKB_CB(skb)->flags = flags & ~(TCPHDR_FIN | TCPHDR_PSH);
 	TCP_SKB_CB(buff)->flags = flags;
 	TCP_SKB_CB(buff)->sacked = TCP_SKB_CB(skb)->sacked;
 
@@ -1328,8 +1328,7 @@
 	u32 in_flight, cwnd;
 
 	/* Don't be strict about the congestion window for the final FIN.  */
-	if ((TCP_SKB_CB(skb)->flags & TCPCB_FLAG_FIN) &&
-	    tcp_skb_pcount(skb) == 1)
+	if ((TCP_SKB_CB(skb)->flags & TCPHDR_FIN) && tcp_skb_pcount(skb) == 1)
 		return 1;
 
 	in_flight = tcp_packets_in_flight(tp);
@@ -1398,7 +1397,7 @@
 	 * Nagle can be ignored during F-RTO too (see RFC4138).
 	 */
 	if (tcp_urg_mode(tp) || (tp->frto_counter == 2) ||
-	    (TCP_SKB_CB(skb)->flags & TCPCB_FLAG_FIN))
+	    (TCP_SKB_CB(skb)->flags & TCPHDR_FIN))
 		return 1;
 
 	if (!tcp_nagle_check(tp, skb, cur_mss, nonagle))
@@ -1487,7 +1486,7 @@
 
 	/* PSH and FIN should only be set in the second packet. */
 	flags = TCP_SKB_CB(skb)->flags;
-	TCP_SKB_CB(skb)->flags = flags & ~(TCPCB_FLAG_FIN | TCPCB_FLAG_PSH);
+	TCP_SKB_CB(skb)->flags = flags & ~(TCPHDR_FIN | TCPHDR_PSH);
 	TCP_SKB_CB(buff)->flags = flags;
 
 	/* This packet was never sent out yet, so no SACK bits. */
@@ -1518,7 +1517,7 @@
 	const struct inet_connection_sock *icsk = inet_csk(sk);
 	u32 send_win, cong_win, limit, in_flight;
 
-	if (TCP_SKB_CB(skb)->flags & TCPCB_FLAG_FIN)
+	if (TCP_SKB_CB(skb)->flags & TCPHDR_FIN)
 		goto send_now;
 
 	if (icsk->icsk_ca_state != TCP_CA_Open)
@@ -1644,7 +1643,7 @@
 
 	TCP_SKB_CB(nskb)->seq = TCP_SKB_CB(skb)->seq;
 	TCP_SKB_CB(nskb)->end_seq = TCP_SKB_CB(skb)->seq + probe_size;
-	TCP_SKB_CB(nskb)->flags = TCPCB_FLAG_ACK;
+	TCP_SKB_CB(nskb)->flags = TCPHDR_ACK;
 	TCP_SKB_CB(nskb)->sacked = 0;
 	nskb->csum = 0;
 	nskb->ip_summed = skb->ip_summed;
@@ -1669,7 +1668,7 @@
 			sk_wmem_free_skb(sk, skb);
 		} else {
 			TCP_SKB_CB(nskb)->flags |= TCP_SKB_CB(skb)->flags &
-						   ~(TCPCB_FLAG_FIN|TCPCB_FLAG_PSH);
+						   ~(TCPHDR_FIN|TCPHDR_PSH);
 			if (!skb_shinfo(skb)->nr_frags) {
 				skb_pull(skb, copy);
 				if (skb->ip_summed != CHECKSUM_PARTIAL)
@@ -2020,7 +2019,7 @@
 
 	if (!sysctl_tcp_retrans_collapse)
 		return;
-	if (TCP_SKB_CB(skb)->flags & TCPCB_FLAG_SYN)
+	if (TCP_SKB_CB(skb)->flags & TCPHDR_SYN)
 		return;
 
 	tcp_for_write_queue_from_safe(skb, tmp, sk) {
@@ -2112,7 +2111,7 @@
 	 * since it is cheap to do so and saves bytes on the network.
 	 */
 	if (skb->len > 0 &&
-	    (TCP_SKB_CB(skb)->flags & TCPCB_FLAG_FIN) &&
+	    (TCP_SKB_CB(skb)->flags & TCPHDR_FIN) &&
 	    tp->snd_una == (TCP_SKB_CB(skb)->end_seq - 1)) {
 		if (!pskb_trim(skb, 0)) {
 			/* Reuse, even though it does some unnecessary work */
@@ -2301,7 +2300,7 @@
 	mss_now = tcp_current_mss(sk);
 
 	if (tcp_send_head(sk) != NULL) {
-		TCP_SKB_CB(skb)->flags |= TCPCB_FLAG_FIN;
+		TCP_SKB_CB(skb)->flags |= TCPHDR_FIN;
 		TCP_SKB_CB(skb)->end_seq++;
 		tp->write_seq++;
 	} else {
@@ -2318,7 +2317,7 @@
 		skb_reserve(skb, MAX_TCP_HEADER);
 		/* FIN eats a sequence byte, write_seq advanced by tcp_queue_skb(). */
 		tcp_init_nondata_skb(skb, tp->write_seq,
-				     TCPCB_FLAG_ACK | TCPCB_FLAG_FIN);
+				     TCPHDR_ACK | TCPHDR_FIN);
 		tcp_queue_skb(sk, skb);
 	}
 	__tcp_push_pending_frames(sk, mss_now, TCP_NAGLE_OFF);
@@ -2343,7 +2342,7 @@
 	/* Reserve space for headers and prepare control bits. */
 	skb_reserve(skb, MAX_TCP_HEADER);
 	tcp_init_nondata_skb(skb, tcp_acceptable_seq(sk),
-			     TCPCB_FLAG_ACK | TCPCB_FLAG_RST);
+			     TCPHDR_ACK | TCPHDR_RST);
 	/* Send it off. */
 	TCP_SKB_CB(skb)->when = tcp_time_stamp;
 	if (tcp_transmit_skb(sk, skb, 0, priority))
@@ -2363,11 +2362,11 @@
 	struct sk_buff *skb;
 
 	skb = tcp_write_queue_head(sk);
-	if (skb == NULL || !(TCP_SKB_CB(skb)->flags & TCPCB_FLAG_SYN)) {
+	if (skb == NULL || !(TCP_SKB_CB(skb)->flags & TCPHDR_SYN)) {
 		printk(KERN_DEBUG "tcp_send_synack: wrong queue state\n");
 		return -EFAULT;
 	}
-	if (!(TCP_SKB_CB(skb)->flags & TCPCB_FLAG_ACK)) {
+	if (!(TCP_SKB_CB(skb)->flags & TCPHDR_ACK)) {
 		if (skb_cloned(skb)) {
 			struct sk_buff *nskb = skb_copy(skb, GFP_ATOMIC);
 			if (nskb == NULL)
@@ -2381,7 +2380,7 @@
 			skb = nskb;
 		}
 
-		TCP_SKB_CB(skb)->flags |= TCPCB_FLAG_ACK;
+		TCP_SKB_CB(skb)->flags |= TCPHDR_ACK;
 		TCP_ECN_send_synack(tcp_sk(sk), skb);
 	}
 	TCP_SKB_CB(skb)->when = tcp_time_stamp;
@@ -2460,7 +2459,7 @@
 	 * not even correctly set)
 	 */
 	tcp_init_nondata_skb(skb, tcp_rsk(req)->snt_isn,
-			     TCPCB_FLAG_SYN | TCPCB_FLAG_ACK);
+			     TCPHDR_SYN | TCPHDR_ACK);
 
 	if (OPTION_COOKIE_EXTENSION & opts.options) {
 		if (s_data_desired) {
@@ -2592,7 +2591,7 @@
 	skb_reserve(buff, MAX_TCP_HEADER);
 
 	tp->snd_nxt = tp->write_seq;
-	tcp_init_nondata_skb(buff, tp->write_seq++, TCPCB_FLAG_SYN);
+	tcp_init_nondata_skb(buff, tp->write_seq++, TCPHDR_SYN);
 	TCP_ECN_send_syn(sk, buff);
 
 	/* Send it off. */
@@ -2698,7 +2697,7 @@
 
 	/* Reserve space for headers and prepare control bits. */
 	skb_reserve(buff, MAX_TCP_HEADER);
-	tcp_init_nondata_skb(buff, tcp_acceptable_seq(sk), TCPCB_FLAG_ACK);
+	tcp_init_nondata_skb(buff, tcp_acceptable_seq(sk), TCPHDR_ACK);
 
 	/* Send it off, this clears delayed acks for us. */
 	TCP_SKB_CB(buff)->when = tcp_time_stamp;
@@ -2732,7 +2731,7 @@
 	 * end to send an ack.  Don't queue or clone SKB, just
 	 * send it.
 	 */
-	tcp_init_nondata_skb(skb, tp->snd_una - !urgent, TCPCB_FLAG_ACK);
+	tcp_init_nondata_skb(skb, tp->snd_una - !urgent, TCPHDR_ACK);
 	TCP_SKB_CB(skb)->when = tcp_time_stamp;
 	return tcp_transmit_skb(sk, skb, 0, GFP_ATOMIC);
 }
@@ -2762,13 +2761,13 @@
 		if (seg_size < TCP_SKB_CB(skb)->end_seq - TCP_SKB_CB(skb)->seq ||
 		    skb->len > mss) {
 			seg_size = min(seg_size, mss);
-			TCP_SKB_CB(skb)->flags |= TCPCB_FLAG_PSH;
+			TCP_SKB_CB(skb)->flags |= TCPHDR_PSH;
 			if (tcp_fragment(sk, skb, seg_size, mss))
 				return -1;
 		} else if (!tcp_skb_pcount(skb))
 			tcp_set_skb_tso_segs(sk, skb, mss);
 
-		TCP_SKB_CB(skb)->flags |= TCPCB_FLAG_PSH;
+		TCP_SKB_CB(skb)->flags |= TCPHDR_PSH;
 		TCP_SKB_CB(skb)->when = tcp_time_stamp;
 		err = tcp_transmit_skb(sk, skb, 1, GFP_ATOMIC);
 		if (!err)