[ICSK]: Move TCP congestion avoidance members to icsk

This changeset basically moves tcp_sk()->{ca_ops,ca_state,etc} to inet_csk(),
minimal renaming/moving done in this changeset to ease review.

Most of it is just changes of struct tcp_sock * to struct sock * parameters.

With this we move to a state closer to two interesting goals:

1. Generalisation of net/ipv4/tcp_diag.c, becoming inet_diag.c, being used
   for any INET transport protocol that has struct inet_hashinfo and are
   derived from struct inet_connection_sock. Keeps the userspace API, that will
   just not display DCCP sockets, while newer versions of tools can support
   DCCP.

2. INET generic transport pluggable Congestion Avoidance infrastructure, using
   the current TCP CA infrastructure with DCCP.

Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 124 insertions, 99 deletions

diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 71d456148de7..fdd9547fb783 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -325,11 +325,12 @@ static void tcp_init_buffer_space(struct sock *sk)
 /* 5. Recalculate window clamp after socket hit its memory bounds. */
 static void tcp_clamp_window(struct sock *sk, struct tcp_sock *tp)
 {
+	struct inet_connection_sock *icsk = inet_csk(sk);
 	struct sk_buff *skb;
 	unsigned int app_win = tp->rcv_nxt - tp->copied_seq;
 	int ofo_win = 0;
 
-	inet_csk(sk)->icsk_ack.quick = 0;
+	icsk->icsk_ack.quick = 0;
 
 	skb_queue_walk(&tp->out_of_order_queue, skb) {
 		ofo_win += skb->len;
@@ -350,8 +351,8 @@ static void tcp_clamp_window(struct sock *sk, struct tcp_sock *tp)
 		app_win += ofo_win;
 		if (atomic_read(&sk->sk_rmem_alloc) >= 2 * sk->sk_rcvbuf)
 			app_win >>= 1;
-		if (app_win > inet_csk(sk)->icsk_ack.rcv_mss)
-			app_win -= inet_csk(sk)->icsk_ack.rcv_mss;
+		if (app_win > icsk->icsk_ack.rcv_mss)
+			app_win -= icsk->icsk_ack.rcv_mss;
 		app_win = max(app_win, 2U*tp->advmss);
 
 		if (!ofo_win)
@@ -549,8 +550,10 @@ static void tcp_event_data_recv(struct sock *sk, struct tcp_sock *tp, struct sk_
  * To save cycles in the RFC 1323 implementation it was better to break
  * it up into three procedures. -- erics
  */
-static void tcp_rtt_estimator(struct tcp_sock *tp, __u32 mrtt, u32 *usrtt)
+static void tcp_rtt_estimator(struct sock *sk, const __u32 mrtt, u32 *usrtt)
 {
+	struct tcp_sock *tp = tcp_sk(sk);
+	const struct inet_connection_sock *icsk = inet_csk(sk);
 	long m = mrtt; /* RTT */
 
 	/*	The following amusing code comes from Jacobson's
@@ -610,8 +613,8 @@ static void tcp_rtt_estimator(struct tcp_sock *tp, __u32 mrtt, u32 *usrtt)
 		tp->rtt_seq = tp->snd_nxt;
 	}
 
-	if (tp->ca_ops->rtt_sample)
-		tp->ca_ops->rtt_sample(tp, *usrtt);
+	if (icsk->icsk_ca_ops->rtt_sample)
+		icsk->icsk_ca_ops->rtt_sample(sk, *usrtt);
 }
 
 /* Calculate rto without backoff.  This is the second half of Van Jacobson's
@@ -663,9 +666,10 @@ void tcp_update_metrics(struct sock *sk)
 	dst_confirm(dst);
 
 	if (dst && (dst->flags&DST_HOST)) {
+		const struct inet_connection_sock *icsk = inet_csk(sk);
 		int m;
 
-		if (inet_csk(sk)->icsk_backoff || !tp->srtt) {
+		if (icsk->icsk_backoff || !tp->srtt) {
 			/* This session failed to estimate rtt. Why?
 			 * Probably, no packets returned in time.
 			 * Reset our results.
@@ -714,7 +718,7 @@ void tcp_update_metrics(struct sock *sk)
 			    tp->snd_cwnd > dst_metric(dst, RTAX_CWND))
 				dst->metrics[RTAX_CWND-1] = tp->snd_cwnd;
 		} else if (tp->snd_cwnd > tp->snd_ssthresh &&
-			   tp->ca_state == TCP_CA_Open) {
+			   icsk->icsk_ca_state == TCP_CA_Open) {
 			/* Cong. avoidance phase, cwnd is reliable. */
 			if (!dst_metric_locked(dst, RTAX_SSTHRESH))
 				dst->metrics[RTAX_SSTHRESH-1] =
@@ -828,8 +832,10 @@ reset:
 	}
 }
 
-static void tcp_update_reordering(struct tcp_sock *tp, int metric, int ts)
+static void tcp_update_reordering(struct sock *sk, const int metric,
+				  const int ts)
 {
+	struct tcp_sock *tp = tcp_sk(sk);
 	if (metric > tp->reordering) {
 		tp->reordering = min(TCP_MAX_REORDERING, metric);
 
@@ -844,7 +850,7 @@ static void tcp_update_reordering(struct tcp_sock *tp, int metric, int ts)
 			NET_INC_STATS_BH(LINUX_MIB_TCPSACKREORDER);
 #if FASTRETRANS_DEBUG > 1
 		printk(KERN_DEBUG "Disorder%d %d %u f%u s%u rr%d\n",
-		       tp->rx_opt.sack_ok, tp->ca_state,
+		       tp->rx_opt.sack_ok, inet_csk(sk)->icsk_ca_state,
 		       tp->reordering,
 		       tp->fackets_out,
 		       tp->sacked_out,
@@ -906,6 +912,7 @@ static void tcp_update_reordering(struct tcp_sock *tp, int metric, int ts)
 static int
 tcp_sacktag_write_queue(struct sock *sk, struct sk_buff *ack_skb, u32 prior_snd_una)
 {
+	const struct inet_connection_sock *icsk = inet_csk(sk);
 	struct tcp_sock *tp = tcp_sk(sk);
 	unsigned char *ptr = ack_skb->h.raw + TCP_SKB_CB(ack_skb)->sacked;
 	struct tcp_sack_block *sp = (struct tcp_sack_block *)(ptr+2);
@@ -1071,7 +1078,7 @@ tcp_sacktag_write_queue(struct sock *sk, struct sk_buff *ack_skb, u32 prior_snd_
 	 * we have to account for reordering! Ugly,
 	 * but should help.
 	 */
-	if (lost_retrans && tp->ca_state == TCP_CA_Recovery) {
+	if (lost_retrans && icsk->icsk_ca_state == TCP_CA_Recovery) {
 		struct sk_buff *skb;
 
 		sk_stream_for_retrans_queue(skb, sk) {
@@ -1100,8 +1107,8 @@ tcp_sacktag_write_queue(struct sock *sk, struct sk_buff *ack_skb, u32 prior_snd_
 
 	tp->left_out = tp->sacked_out + tp->lost_out;
 
-	if ((reord < tp->fackets_out) && tp->ca_state != TCP_CA_Loss)
-		tcp_update_reordering(tp, ((tp->fackets_out + 1) - reord), 0);
+	if ((reord < tp->fackets_out) && icsk->icsk_ca_state != TCP_CA_Loss)
+		tcp_update_reordering(sk, ((tp->fackets_out + 1) - reord), 0);
 
 #if FASTRETRANS_DEBUG > 0
 	BUG_TRAP((int)tp->sacked_out >= 0);
@@ -1118,17 +1125,18 @@ tcp_sacktag_write_queue(struct sock *sk, struct sk_buff *ack_skb, u32 prior_snd_
  */
 void tcp_enter_frto(struct sock *sk)
 {
+	const struct inet_connection_sock *icsk = inet_csk(sk);
 	struct tcp_sock *tp = tcp_sk(sk);
 	struct sk_buff *skb;
 
 	tp->frto_counter = 1;
 
-	if (tp->ca_state <= TCP_CA_Disorder ||
+	if (icsk->icsk_ca_state <= TCP_CA_Disorder ||
             tp->snd_una == tp->high_seq ||
-            (tp->ca_state == TCP_CA_Loss && !inet_csk(sk)->icsk_retransmits)) {
-		tp->prior_ssthresh = tcp_current_ssthresh(tp);
-		tp->snd_ssthresh = tp->ca_ops->ssthresh(tp);
-		tcp_ca_event(tp, CA_EVENT_FRTO);
+            (icsk->icsk_ca_state == TCP_CA_Loss && !icsk->icsk_retransmits)) {
+		tp->prior_ssthresh = tcp_current_ssthresh(sk);
+		tp->snd_ssthresh = icsk->icsk_ca_ops->ssthresh(sk);
+		tcp_ca_event(sk, CA_EVENT_FRTO);
 	}
 
 	/* Have to clear retransmission markers here to keep the bookkeeping
@@ -1145,7 +1153,7 @@ void tcp_enter_frto(struct sock *sk)
 	}
 	tcp_sync_left_out(tp);
 
-	tcp_set_ca_state(tp, TCP_CA_Open);
+	tcp_set_ca_state(sk, TCP_CA_Open);
 	tp->frto_highmark = tp->snd_nxt;
 }
 
@@ -1191,7 +1199,7 @@ static void tcp_enter_frto_loss(struct sock *sk)
 
 	tp->reordering = min_t(unsigned int, tp->reordering,
 					     sysctl_tcp_reordering);
-	tcp_set_ca_state(tp, TCP_CA_Loss);
+	tcp_set_ca_state(sk, TCP_CA_Loss);
 	tp->high_seq = tp->frto_highmark;
 	TCP_ECN_queue_cwr(tp);
 }
@@ -1215,16 +1223,17 @@ void tcp_clear_retrans(struct tcp_sock *tp)
  */
 void tcp_enter_loss(struct sock *sk, int how)
 {
+	const struct inet_connection_sock *icsk = inet_csk(sk);
 	struct tcp_sock *tp = tcp_sk(sk);
 	struct sk_buff *skb;
 	int cnt = 0;
 
 	/* Reduce ssthresh if it has not yet been made inside this window. */
-	if (tp->ca_state <= TCP_CA_Disorder || tp->snd_una == tp->high_seq ||
-	    (tp->ca_state == TCP_CA_Loss && !inet_csk(sk)->icsk_retransmits)) {
-		tp->prior_ssthresh = tcp_current_ssthresh(tp);
-		tp->snd_ssthresh = tp->ca_ops->ssthresh(tp);
-		tcp_ca_event(tp, CA_EVENT_LOSS);
+	if (icsk->icsk_ca_state <= TCP_CA_Disorder || tp->snd_una == tp->high_seq ||
+	    (icsk->icsk_ca_state == TCP_CA_Loss && !icsk->icsk_retransmits)) {
+		tp->prior_ssthresh = tcp_current_ssthresh(sk);
+		tp->snd_ssthresh = icsk->icsk_ca_ops->ssthresh(sk);
+		tcp_ca_event(sk, CA_EVENT_LOSS);
 	}
 	tp->snd_cwnd	   = 1;
 	tp->snd_cwnd_cnt   = 0;
@@ -1255,7 +1264,7 @@ void tcp_enter_loss(struct sock *sk, int how)
 
 	tp->reordering = min_t(unsigned int, tp->reordering,
 					     sysctl_tcp_reordering);
-	tcp_set_ca_state(tp, TCP_CA_Loss);
+	tcp_set_ca_state(sk, TCP_CA_Loss);
 	tp->high_seq = tp->snd_nxt;
 	TCP_ECN_queue_cwr(tp);
 }
@@ -1272,13 +1281,14 @@ static int tcp_check_sack_reneging(struct sock *sk)
 	 */
 	if ((skb = skb_peek(&sk->sk_write_queue)) != NULL &&
 	    (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_ACKED)) {
+		struct inet_connection_sock *icsk = inet_csk(sk);
 		NET_INC_STATS_BH(LINUX_MIB_TCPSACKRENEGING);
 
 		tcp_enter_loss(sk, 1);
-		inet_csk(sk)->icsk_retransmits++;
+		icsk->icsk_retransmits++;
 		tcp_retransmit_skb(sk, skb_peek(&sk->sk_write_queue));
 		inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS,
-					  inet_csk(sk)->icsk_rto, TCP_RTO_MAX);
+					  icsk->icsk_rto, TCP_RTO_MAX);
 		return 1;
 	}
 	return 0;
@@ -1431,8 +1441,9 @@ static int tcp_time_to_recover(struct sock *sk, struct tcp_sock *tp)
  * in assumption of absent reordering, interpret this as reordering.
  * The only another reason could be bug in receiver TCP.
  */
-static void tcp_check_reno_reordering(struct tcp_sock *tp, int addend)
+static void tcp_check_reno_reordering(struct sock *sk, const int addend)
 {
+	struct tcp_sock *tp = tcp_sk(sk);
 	u32 holes;
 
 	holes = max(tp->lost_out, 1U);
@@ -1440,16 +1451,17 @@ static void tcp_check_reno_reordering(struct tcp_sock *tp, int addend)
 
 	if ((tp->sacked_out + holes) > tp->packets_out) {
 		tp->sacked_out = tp->packets_out - holes;
-		tcp_update_reordering(tp, tp->packets_out+addend, 0);
+		tcp_update_reordering(sk, tp->packets_out + addend, 0);
 	}
 }
 
 /* Emulate SACKs for SACKless connection: account for a new dupack. */
 
-static void tcp_add_reno_sack(struct tcp_sock *tp)
+static void tcp_add_reno_sack(struct sock *sk)
 {
+	struct tcp_sock *tp = tcp_sk(sk);
 	tp->sacked_out++;
-	tcp_check_reno_reordering(tp, 0);
+	tcp_check_reno_reordering(sk, 0);
 	tcp_sync_left_out(tp);
 }
 
@@ -1464,7 +1476,7 @@ static void tcp_remove_reno_sacks(struct sock *sk, struct tcp_sock *tp, int acke
 		else
 			tp->sacked_out -= acked-1;
 	}
-	tcp_check_reno_reordering(tp, acked);
+	tcp_check_reno_reordering(sk, acked);
 	tcp_sync_left_out(tp);
 }
 
@@ -1538,14 +1550,16 @@ static inline void tcp_moderate_cwnd(struct tcp_sock *tp)
 }
 
 /* Decrease cwnd each second ack. */
-static void tcp_cwnd_down(struct tcp_sock *tp)
+static void tcp_cwnd_down(struct sock *sk)
 {
+	const struct inet_connection_sock *icsk = inet_csk(sk);
+	struct tcp_sock *tp = tcp_sk(sk);
 	int decr = tp->snd_cwnd_cnt + 1;
 
 	tp->snd_cwnd_cnt = decr&1;
 	decr >>= 1;
 
-	if (decr && tp->snd_cwnd > tp->ca_ops->min_cwnd(tp))
+	if (decr && tp->snd_cwnd > icsk->icsk_ca_ops->min_cwnd(sk))
 		tp->snd_cwnd -= decr;
 
 	tp->snd_cwnd = min(tp->snd_cwnd, tcp_packets_in_flight(tp)+1);
@@ -1579,11 +1593,15 @@ static void DBGUNDO(struct sock *sk, struct tcp_sock *tp, const char *msg)
 #define DBGUNDO(x...) do { } while (0)
 #endif
 
-static void tcp_undo_cwr(struct tcp_sock *tp, int undo)
+static void tcp_undo_cwr(struct sock *sk, const int undo)
 {
+	struct tcp_sock *tp = tcp_sk(sk);
+
 	if (tp->prior_ssthresh) {
-		if (tp->ca_ops->undo_cwnd)
-			tp->snd_cwnd = tp->ca_ops->undo_cwnd(tp);
+		const struct inet_connection_sock *icsk = inet_csk(sk);
+
+		if (icsk->icsk_ca_ops->undo_cwnd)
+			tp->snd_cwnd = icsk->icsk_ca_ops->undo_cwnd(sk);
 		else
 			tp->snd_cwnd = max(tp->snd_cwnd, tp->snd_ssthresh<<1);
 
@@ -1611,9 +1629,9 @@ static int tcp_try_undo_recovery(struct sock *sk, struct tcp_sock *tp)
 		/* Happy end! We did not retransmit anything
 		 * or our original transmission succeeded.
 		 */
-		DBGUNDO(sk, tp, tp->ca_state == TCP_CA_Loss ? "loss" : "retrans");
-		tcp_undo_cwr(tp, 1);
-		if (tp->ca_state == TCP_CA_Loss)
+		DBGUNDO(sk, tp, inet_csk(sk)->icsk_ca_state == TCP_CA_Loss ? "loss" : "retrans");
+		tcp_undo_cwr(sk, 1);
+		if (inet_csk(sk)->icsk_ca_state == TCP_CA_Loss)
 			NET_INC_STATS_BH(LINUX_MIB_TCPLOSSUNDO);
 		else
 			NET_INC_STATS_BH(LINUX_MIB_TCPFULLUNDO);
@@ -1626,7 +1644,7 @@ static int tcp_try_undo_recovery(struct sock *sk, struct tcp_sock *tp)
 		tcp_moderate_cwnd(tp);
 		return 1;
 	}
-	tcp_set_ca_state(tp, TCP_CA_Open);
+	tcp_set_ca_state(sk, TCP_CA_Open);
 	return 0;
 }
 
@@ -1635,7 +1653,7 @@ static void tcp_try_undo_dsack(struct sock *sk, struct tcp_sock *tp)
 {
 	if (tp->undo_marker && !tp->undo_retrans) {
 		DBGUNDO(sk, tp, "D-SACK");
-		tcp_undo_cwr(tp, 1);
+		tcp_undo_cwr(sk, 1);
 		tp->undo_marker = 0;
 		NET_INC_STATS_BH(LINUX_MIB_TCPDSACKUNDO);
 	}
@@ -1656,10 +1674,10 @@ static int tcp_try_undo_partial(struct sock *sk, struct tcp_sock *tp,
 		if (tp->retrans_out == 0)
 			tp->retrans_stamp = 0;
 
-		tcp_update_reordering(tp, tcp_fackets_out(tp)+acked, 1);
+		tcp_update_reordering(sk, tcp_fackets_out(tp) + acked, 1);
 
 		DBGUNDO(sk, tp, "Hoe");
-		tcp_undo_cwr(tp, 0);
+		tcp_undo_cwr(sk, 0);
 		NET_INC_STATS_BH(LINUX_MIB_TCPPARTIALUNDO);
 
 		/* So... Do not make Hoe's retransmit yet.
@@ -1682,22 +1700,23 @@ static int tcp_try_undo_loss(struct sock *sk, struct tcp_sock *tp)
 		DBGUNDO(sk, tp, "partial loss");
 		tp->lost_out = 0;
 		tp->left_out = tp->sacked_out;
-		tcp_undo_cwr(tp, 1);
+		tcp_undo_cwr(sk, 1);
 		NET_INC_STATS_BH(LINUX_MIB_TCPLOSSUNDO);
 		inet_csk(sk)->icsk_retransmits = 0;
 		tp->undo_marker = 0;
 		if (!IsReno(tp))
-			tcp_set_ca_state(tp, TCP_CA_Open);
+			tcp_set_ca_state(sk, TCP_CA_Open);
 		return 1;
 	}
 	return 0;
 }
 
-static inline void tcp_complete_cwr(struct tcp_sock *tp)
+static inline void tcp_complete_cwr(struct sock *sk)
 {
+	struct tcp_sock *tp = tcp_sk(sk);
 	tp->snd_cwnd = min(tp->snd_cwnd, tp->snd_ssthresh);
 	tp->snd_cwnd_stamp = tcp_time_stamp;
-	tcp_ca_event(tp, CA_EVENT_COMPLETE_CWR);
+	tcp_ca_event(sk, CA_EVENT_COMPLETE_CWR);
 }
 
 static void tcp_try_to_open(struct sock *sk, struct tcp_sock *tp, int flag)
@@ -1708,21 +1727,21 @@ static void tcp_try_to_open(struct sock *sk, struct tcp_sock *tp, int flag)
 		tp->retrans_stamp = 0;
 
 	if (flag&FLAG_ECE)
-		tcp_enter_cwr(tp);
+		tcp_enter_cwr(sk);
 
-	if (tp->ca_state != TCP_CA_CWR) {
+	if (inet_csk(sk)->icsk_ca_state != TCP_CA_CWR) {
 		int state = TCP_CA_Open;
 
 		if (tp->left_out || tp->retrans_out || tp->undo_marker)
 			state = TCP_CA_Disorder;
 
-		if (tp->ca_state != state) {
-			tcp_set_ca_state(tp, state);
+		if (inet_csk(sk)->icsk_ca_state != state) {
+			tcp_set_ca_state(sk, state);
 			tp->high_seq = tp->snd_nxt;
 		}
 		tcp_moderate_cwnd(tp);
 	} else {
-		tcp_cwnd_down(tp);
+		tcp_cwnd_down(sk);
 	}
 }
 
@@ -1741,6 +1760,7 @@ static void
 tcp_fastretrans_alert(struct sock *sk, u32 prior_snd_una,
 		      int prior_packets, int flag)
 {
+	struct inet_connection_sock *icsk = inet_csk(sk);
 	struct tcp_sock *tp = tcp_sk(sk);
 	int is_dupack = (tp->snd_una == prior_snd_una && !(flag&FLAG_NOT_DUP));
 
@@ -1764,7 +1784,7 @@ tcp_fastretrans_alert(struct sock *sk, u32 prior_snd_una,
 	/* C. Process data loss notification, provided it is valid. */
 	if ((flag&FLAG_DATA_LOST) &&
 	    before(tp->snd_una, tp->high_seq) &&
-	    tp->ca_state != TCP_CA_Open &&
+	    icsk->icsk_ca_state != TCP_CA_Open &&
 	    tp->fackets_out > tp->reordering) {
 		tcp_mark_head_lost(sk, tp, tp->fackets_out-tp->reordering, tp->high_seq);
 		NET_INC_STATS_BH(LINUX_MIB_TCPLOSS);
@@ -1775,14 +1795,14 @@ tcp_fastretrans_alert(struct sock *sk, u32 prior_snd_una,
 
 	/* E. Check state exit conditions. State can be terminated
 	 *    when high_seq is ACKed. */
-	if (tp->ca_state == TCP_CA_Open) {
+	if (icsk->icsk_ca_state == TCP_CA_Open) {
 		if (!sysctl_tcp_frto)
 			BUG_TRAP(tp->retrans_out == 0);
 		tp->retrans_stamp = 0;
 	} else if (!before(tp->snd_una, tp->high_seq)) {
-		switch (tp->ca_state) {
+		switch (icsk->icsk_ca_state) {
 		case TCP_CA_Loss:
-			inet_csk(sk)->icsk_retransmits = 0;
+			icsk->icsk_retransmits = 0;
 			if (tcp_try_undo_recovery(sk, tp))
 				return;
 			break;
@@ -1791,8 +1811,8 @@ tcp_fastretrans_alert(struct sock *sk, u32 prior_snd_una,
 			/* CWR is to be held something *above* high_seq
 			 * is ACKed for CWR bit to reach receiver. */
 			if (tp->snd_una != tp->high_seq) {
-				tcp_complete_cwr(tp);
-				tcp_set_ca_state(tp, TCP_CA_Open);
+				tcp_complete_cwr(sk);
+				tcp_set_ca_state(sk, TCP_CA_Open);
 			}
 			break;
 
@@ -1803,7 +1823,7 @@ tcp_fastretrans_alert(struct sock *sk, u32 prior_snd_una,
 			     * catching for all duplicate ACKs. */
 			    IsReno(tp) || tp->snd_una != tp->high_seq) {
 				tp->undo_marker = 0;
-				tcp_set_ca_state(tp, TCP_CA_Open);
+				tcp_set_ca_state(sk, TCP_CA_Open);
 			}
 			break;
 
@@ -1812,17 +1832,17 @@ tcp_fastretrans_alert(struct sock *sk, u32 prior_snd_una,
 				tcp_reset_reno_sack(tp);
 			if (tcp_try_undo_recovery(sk, tp))
 				return;
-			tcp_complete_cwr(tp);
+			tcp_complete_cwr(sk);
 			break;
 		}
 	}
 
 	/* F. Process state. */
-	switch (tp->ca_state) {
+	switch (icsk->icsk_ca_state) {
 	case TCP_CA_Recovery:
 		if (prior_snd_una == tp->snd_una) {
 			if (IsReno(tp) && is_dupack)
-				tcp_add_reno_sack(tp);
+				tcp_add_reno_sack(sk);
 		} else {
 			int acked = prior_packets - tp->packets_out;
 			if (IsReno(tp))
@@ -1832,13 +1852,13 @@ tcp_fastretrans_alert(struct sock *sk, u32 prior_snd_una,
 		break;
 	case TCP_CA_Loss:
 		if (flag&FLAG_DATA_ACKED)
-			inet_csk(sk)->icsk_retransmits = 0;
+			icsk->icsk_retransmits = 0;
 		if (!tcp_try_undo_loss(sk, tp)) {
 			tcp_moderate_cwnd(tp);
 			tcp_xmit_retransmit_queue(sk);
 			return;
 		}
-		if (tp->ca_state != TCP_CA_Open)
+		if (icsk->icsk_ca_state != TCP_CA_Open)
 			return;
 		/* Loss is undone; fall through to processing in Open state. */
 	default:
@@ -1846,10 +1866,10 @@ tcp_fastretrans_alert(struct sock *sk, u32 prior_snd_una,
 			if (tp->snd_una != prior_snd_una)
 				tcp_reset_reno_sack(tp);
 			if (is_dupack)
-				tcp_add_reno_sack(tp);
+				tcp_add_reno_sack(sk);
 		}
 
-		if (tp->ca_state == TCP_CA_Disorder)
+		if (icsk->icsk_ca_state == TCP_CA_Disorder)
 			tcp_try_undo_dsack(sk, tp);
 
 		if (!tcp_time_to_recover(sk, tp)) {
@@ -1869,20 +1889,20 @@ tcp_fastretrans_alert(struct sock *sk, u32 prior_snd_una,
 		tp->undo_marker = tp->snd_una;
 		tp->undo_retrans = tp->retrans_out;
 
-		if (tp->ca_state < TCP_CA_CWR) {
+		if (icsk->icsk_ca_state < TCP_CA_CWR) {
 			if (!(flag&FLAG_ECE))
-				tp->prior_ssthresh = tcp_current_ssthresh(tp);
-			tp->snd_ssthresh = tp->ca_ops->ssthresh(tp);
+				tp->prior_ssthresh = tcp_current_ssthresh(sk);
+			tp->snd_ssthresh = icsk->icsk_ca_ops->ssthresh(sk);
 			TCP_ECN_queue_cwr(tp);
 		}
 
 		tp->snd_cwnd_cnt = 0;
-		tcp_set_ca_state(tp, TCP_CA_Recovery);
+		tcp_set_ca_state(sk, TCP_CA_Recovery);
 	}
 
 	if (is_dupack || tcp_head_timedout(sk, tp))
 		tcp_update_scoreboard(sk, tp);
-	tcp_cwnd_down(tp);
+	tcp_cwnd_down(sk);
 	tcp_xmit_retransmit_queue(sk);
 }
 
@@ -1908,7 +1928,7 @@ static void tcp_ack_saw_tstamp(struct sock *sk, u32 *usrtt, int flag)
 	 */
 	struct tcp_sock *tp = tcp_sk(sk);
 	const __u32 seq_rtt = tcp_time_stamp - tp->rx_opt.rcv_tsecr;
-	tcp_rtt_estimator(tp, seq_rtt, usrtt);
+	tcp_rtt_estimator(sk, seq_rtt, usrtt);
 	tcp_set_rto(sk);
 	inet_csk(sk)->icsk_backoff = 0;
 	tcp_bound_rto(sk);
@@ -1928,7 +1948,7 @@ static void tcp_ack_no_tstamp(struct sock *sk, u32 seq_rtt, u32 *usrtt, int flag
 	if (flag & FLAG_RETRANS_DATA_ACKED)
 		return;
 
-	tcp_rtt_estimator(tcp_sk(sk), seq_rtt, usrtt);
+	tcp_rtt_estimator(sk, seq_rtt, usrtt);
 	tcp_set_rto(sk);
 	inet_csk(sk)->icsk_backoff = 0;
 	tcp_bound_rto(sk);
@@ -1945,11 +1965,12 @@ static inline void tcp_ack_update_rtt(struct sock *sk, const int flag,
 		tcp_ack_no_tstamp(sk, seq_rtt, usrtt, flag);
 }
 
-static inline void tcp_cong_avoid(struct tcp_sock *tp, u32 ack, u32 rtt,
+static inline void tcp_cong_avoid(struct sock *sk, u32 ack, u32 rtt,
 				  u32 in_flight, int good)
 {
-	tp->ca_ops->cong_avoid(tp, ack, rtt, in_flight, good);
-	tp->snd_cwnd_stamp = tcp_time_stamp;
+	const struct inet_connection_sock *icsk = inet_csk(sk);
+	icsk->icsk_ca_ops->cong_avoid(sk, ack, rtt, in_flight, good);
+	tcp_sk(sk)->snd_cwnd_stamp = tcp_time_stamp;
 }
 
 /* Restart timer after forward progress on connection.
@@ -2098,11 +2119,12 @@ static int tcp_clean_rtx_queue(struct sock *sk, __s32 *seq_rtt_p, s32 *seq_usrtt
 	}
 
 	if (acked&FLAG_ACKED) {
+		const struct inet_connection_sock *icsk = inet_csk(sk);
 		tcp_ack_update_rtt(sk, acked, seq_rtt, seq_usrtt);
 		tcp_ack_packets_out(sk, tp);
 
-		if (tp->ca_ops->pkts_acked)
-			tp->ca_ops->pkts_acked(tp, pkts_acked);
+		if (icsk->icsk_ca_ops->pkts_acked)
+			icsk->icsk_ca_ops->pkts_acked(sk, pkts_acked);
 	}
 
 #if FASTRETRANS_DEBUG > 0
@@ -2110,19 +2132,20 @@ static int tcp_clean_rtx_queue(struct sock *sk, __s32 *seq_rtt_p, s32 *seq_usrtt
 	BUG_TRAP((int)tp->lost_out >= 0);
 	BUG_TRAP((int)tp->retrans_out >= 0);
 	if (!tp->packets_out && tp->rx_opt.sack_ok) {
+		const struct inet_connection_sock *icsk = inet_csk(sk);
 		if (tp->lost_out) {
 			printk(KERN_DEBUG "Leak l=%u %d\n",
-			       tp->lost_out, tp->ca_state);
+			       tp->lost_out, icsk->icsk_ca_state);
 			tp->lost_out = 0;
 		}
 		if (tp->sacked_out) {
 			printk(KERN_DEBUG "Leak s=%u %d\n",
-			       tp->sacked_out, tp->ca_state);
+			       tp->sacked_out, icsk->icsk_ca_state);
 			tp->sacked_out = 0;
 		}
 		if (tp->retrans_out) {
 			printk(KERN_DEBUG "Leak r=%u %d\n",
-			       tp->retrans_out, tp->ca_state);
+			       tp->retrans_out, icsk->icsk_ca_state);
 			tp->retrans_out = 0;
 		}
 	}
@@ -2152,16 +2175,17 @@ static void tcp_ack_probe(struct sock *sk)
 	}
 }
 
-static inline int tcp_ack_is_dubious(struct tcp_sock *tp, int flag)
+static inline int tcp_ack_is_dubious(const struct sock *sk, const int flag)
 {
 	return (!(flag & FLAG_NOT_DUP) || (flag & FLAG_CA_ALERT) ||
-		tp->ca_state != TCP_CA_Open);
+		inet_csk(sk)->icsk_ca_state != TCP_CA_Open);
 }
 
-static inline int tcp_may_raise_cwnd(struct tcp_sock *tp, int flag)
+static inline int tcp_may_raise_cwnd(const struct sock *sk, const int flag)
 {
+	const struct tcp_sock *tp = tcp_sk(sk);
 	return (!(flag & FLAG_ECE) || tp->snd_cwnd < tp->snd_ssthresh) &&
-		!((1<<tp->ca_state)&(TCPF_CA_Recovery|TCPF_CA_CWR));
+		!((1 << inet_csk(sk)->icsk_ca_state) & (TCPF_CA_Recovery | TCPF_CA_CWR));
 }
 
 /* Check that window update is acceptable.
@@ -2251,6 +2275,7 @@ static void tcp_process_frto(struct sock *sk, u32 prior_snd_una)
 /* This routine deals with incoming acks, but not outgoing ones. */
 static int tcp_ack(struct sock *sk, struct sk_buff *skb, int flag)
 {
+	struct inet_connection_sock *icsk = inet_csk(sk);
 	struct tcp_sock *tp = tcp_sk(sk);
 	u32 prior_snd_una = tp->snd_una;
 	u32 ack_seq = TCP_SKB_CB(skb)->seq;
@@ -2278,7 +2303,7 @@ static int tcp_ack(struct sock *sk, struct sk_buff *skb, int flag)
 		tp->snd_una = ack;
 		flag |= FLAG_WIN_UPDATE;
 
-		tcp_ca_event(tp, CA_EVENT_FAST_ACK);
+		tcp_ca_event(sk, CA_EVENT_FAST_ACK);
 
 		NET_INC_STATS_BH(LINUX_MIB_TCPHPACKS);
 	} else {
@@ -2295,7 +2320,7 @@ static int tcp_ack(struct sock *sk, struct sk_buff *skb, int flag)
 		if (TCP_ECN_rcv_ecn_echo(tp, skb->h.th))
 			flag |= FLAG_ECE;
 
-		tcp_ca_event(tp, CA_EVENT_SLOW_ACK);
+		tcp_ca_event(sk, CA_EVENT_SLOW_ACK);
 	}
 
 	/* We passed data and got it acked, remove any soft error
@@ -2311,19 +2336,19 @@ static int tcp_ack(struct sock *sk, struct sk_buff *skb, int flag)
 
 	/* See if we can take anything off of the retransmit queue. */
 	flag |= tcp_clean_rtx_queue(sk, &seq_rtt,
-				    tp->ca_ops->rtt_sample ? &seq_usrtt : NULL);
+				    icsk->icsk_ca_ops->rtt_sample ? &seq_usrtt : NULL);
 
 	if (tp->frto_counter)
 		tcp_process_frto(sk, prior_snd_una);
 
-	if (tcp_ack_is_dubious(tp, flag)) {
+	if (tcp_ack_is_dubious(sk, flag)) {
 		/* Advanve CWND, if state allows this. */
-		if ((flag & FLAG_DATA_ACKED) && tcp_may_raise_cwnd(tp, flag))
-			tcp_cong_avoid(tp, ack,  seq_rtt, prior_in_flight, 0);
+		if ((flag & FLAG_DATA_ACKED) && tcp_may_raise_cwnd(sk, flag))
+			tcp_cong_avoid(sk, ack,  seq_rtt, prior_in_flight, 0);
 		tcp_fastretrans_alert(sk, prior_snd_una, prior_packets, flag);
 	} else {
 		if ((flag & FLAG_DATA_ACKED))
-			tcp_cong_avoid(tp, ack, seq_rtt, prior_in_flight, 1);
+			tcp_cong_avoid(sk, ack, seq_rtt, prior_in_flight, 1);
 	}
 
 	if ((flag & FLAG_FORWARD_PROGRESS) || !(flag&FLAG_NOT_DUP))
@@ -2332,7 +2357,7 @@ static int tcp_ack(struct sock *sk, struct sk_buff *skb, int flag)
 	return 1;
 
 no_queue:
-	tp->probes_out = 0;
+	icsk->icsk_probes_out = 0;
 
 	/* If this ack opens up a zero window, clear backoff.  It was
 	 * being used to time the probes, and is probably far higher than
@@ -3301,12 +3326,12 @@ void tcp_cwnd_application_limited(struct sock *sk)
 {
 	struct tcp_sock *tp = tcp_sk(sk);
 
-	if (tp->ca_state == TCP_CA_Open &&
+	if (inet_csk(sk)->icsk_ca_state == TCP_CA_Open &&
 	    sk->sk_socket && !test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) {
 		/* Limited by application or receiver window. */
 		u32 win_used = max(tp->snd_cwnd_used, 2U);
 		if (win_used < tp->snd_cwnd) {
-			tp->snd_ssthresh = tcp_current_ssthresh(tp);
+			tp->snd_ssthresh = tcp_current_ssthresh(sk);
 			tp->snd_cwnd = (tp->snd_cwnd + win_used) >> 1;
 		}
 		tp->snd_cwnd_used = 0;
@@ -3935,7 +3960,7 @@ static int tcp_rcv_synsent_state_process(struct sock *sk, struct sk_buff *skb,
 
 		tcp_init_metrics(sk);
 
-		tcp_init_congestion_control(tp);
+		tcp_init_congestion_control(sk);
 
 		/* Prevent spurious tcp_cwnd_restart() on first data
 		 * packet.
@@ -4212,7 +4237,7 @@ int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb,
 
 				tcp_init_metrics(sk);
 
-				tcp_init_congestion_control(tp);
+				tcp_init_congestion_control(sk);
 
 				/* Prevent spurious tcp_cwnd_restart() on
 				 * first data packet.