[NET]: Introduce inet_connection_sock

This creates struct inet_connection_sock, moving members out of struct
tcp_sock that are shareable with other INET connection oriented
protocols, such as DCCP, that in my private tree already uses most of
these members.

The functions that operate on these members were renamed, using a
inet_csk_ prefix while not being moved yet to a new file, so as to
ease the review of these changes.

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

10 files changed, 440 insertions, 396 deletions

diff --git a/net/ipv4/inet_hashtables.c b/net/ipv4/inet_hashtables.c
index d94e962958a..e8d29fe736d 100644
--- a/net/ipv4/inet_hashtables.c
+++ b/net/ipv4/inet_hashtables.c
@@ -19,6 +19,7 @@
 #include <linux/slab.h>
 #include <linux/wait.h>
 
+#include <net/inet_connection_sock.h>
 #include <net/inet_hashtables.h>
 
 /*
@@ -56,10 +57,9 @@ void inet_bind_bucket_destroy(kmem_cache_t *cachep, struct inet_bind_bucket *tb)
 void inet_bind_hash(struct sock *sk, struct inet_bind_bucket *tb,
 		    const unsigned short snum)
 {
-	struct inet_sock *inet = inet_sk(sk);
-	inet->num	= snum;
+	inet_sk(sk)->num = snum;
 	sk_add_bind_node(sk, &tb->owners);
-	inet->bind_hash	= tb;
+	inet_csk(sk)->icsk_bind_hash = tb;
 }
 
 EXPORT_SYMBOL(inet_bind_hash);
@@ -69,16 +69,15 @@ EXPORT_SYMBOL(inet_bind_hash);
  */
 static void __inet_put_port(struct inet_hashinfo *hashinfo, struct sock *sk)
 {
-	struct inet_sock *inet = inet_sk(sk);
-	const int bhash = inet_bhashfn(inet->num, hashinfo->bhash_size);
+	const int bhash = inet_bhashfn(inet_sk(sk)->num, hashinfo->bhash_size);
 	struct inet_bind_hashbucket *head = &hashinfo->bhash[bhash];
 	struct inet_bind_bucket *tb;
 
 	spin_lock(&head->lock);
-	tb = inet->bind_hash;
+	tb = inet_csk(sk)->icsk_bind_hash;
 	__sk_del_bind_node(sk);
-	inet->bind_hash = NULL;
-	inet->num = 0;
+	inet_csk(sk)->icsk_bind_hash = NULL;
+	inet_sk(sk)->num = 0;
 	inet_bind_bucket_destroy(hashinfo->bind_bucket_cachep, tb);
 	spin_unlock(&head->lock);
 }
diff --git a/net/ipv4/inet_timewait_sock.c b/net/ipv4/inet_timewait_sock.c
index ceb577c7423..5cba59b869f 100644
--- a/net/ipv4/inet_timewait_sock.c
+++ b/net/ipv4/inet_timewait_sock.c
@@ -56,6 +56,7 @@ void __inet_twsk_hashdance(struct inet_timewait_sock *tw, struct sock *sk,
 			   struct inet_hashinfo *hashinfo)
 {
 	const struct inet_sock *inet = inet_sk(sk);
+	const struct inet_connection_sock *icsk = inet_csk(sk);
 	struct inet_ehash_bucket *ehead = &hashinfo->ehash[sk->sk_hashent];
 	struct inet_bind_hashbucket *bhead;
 	/* Step 1: Put TW into bind hash. Original socket stays there too.
@@ -64,8 +65,8 @@ void __inet_twsk_hashdance(struct inet_timewait_sock *tw, struct sock *sk,
 	 */
 	bhead = &hashinfo->bhash[inet_bhashfn(inet->num, hashinfo->bhash_size)];
 	spin_lock(&bhead->lock);
-	tw->tw_tb = inet->bind_hash;
-	BUG_TRAP(inet->bind_hash);
+	tw->tw_tb = icsk->icsk_bind_hash;
+	BUG_TRAP(icsk->icsk_bind_hash);
 	inet_twsk_add_bind_node(tw, &tw->tw_tb->owners);
 	spin_unlock(&bhead->lock);
 
diff --git a/net/ipv4/syncookies.c b/net/ipv4/syncookies.c
index 72d01444218..8692cb9d4bd 100644
--- a/net/ipv4/syncookies.c
+++ b/net/ipv4/syncookies.c
@@ -180,7 +180,7 @@ static inline struct sock *get_cookie_sock(struct sock *sk, struct sk_buff *skb,
 
 	child = tp->af_specific->syn_recv_sock(sk, skb, req, dst);
 	if (child)
-		tcp_acceptq_queue(sk, req, child);
+		inet_csk_reqsk_queue_add(sk, req, child);
 	else
 		reqsk_free(req);
 
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index f1a708bf7a9..8177b86570d 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -313,7 +313,7 @@ EXPORT_SYMBOL(tcp_enter_memory_pressure);
 static __inline__ unsigned int tcp_listen_poll(struct sock *sk,
 					       poll_table *wait)
 {
-	return !reqsk_queue_empty(&tcp_sk(sk)->accept_queue) ? (POLLIN | POLLRDNORM) : 0;
+	return !reqsk_queue_empty(&inet_csk(sk)->icsk_accept_queue) ? (POLLIN | POLLRDNORM) : 0;
 }
 
 /*
@@ -458,15 +458,15 @@ int tcp_ioctl(struct sock *sk, int cmd, unsigned long arg)
 int tcp_listen_start(struct sock *sk)
 {
 	struct inet_sock *inet = inet_sk(sk);
-	struct tcp_sock *tp = tcp_sk(sk);
-	int rc = reqsk_queue_alloc(&tp->accept_queue, TCP_SYNQ_HSIZE);
+	struct inet_connection_sock *icsk = inet_csk(sk);
+	int rc = reqsk_queue_alloc(&icsk->icsk_accept_queue, TCP_SYNQ_HSIZE);
 
 	if (rc != 0)
 		return rc;
 
 	sk->sk_max_ack_backlog = 0;
 	sk->sk_ack_backlog = 0;
-	tcp_delack_init(tp);
+	inet_csk_delack_init(sk);
 
 	/* There is race window here: we announce ourselves listening,
 	 * but this transition is still not validated by get_port().
@@ -484,7 +484,7 @@ int tcp_listen_start(struct sock *sk)
 	}
 
 	sk->sk_state = TCP_CLOSE;
-	__reqsk_queue_destroy(&tp->accept_queue);
+	__reqsk_queue_destroy(&icsk->icsk_accept_queue);
 	return -EADDRINUSE;
 }
 
@@ -495,14 +495,14 @@ int tcp_listen_start(struct sock *sk)
 
 static void tcp_listen_stop (struct sock *sk)
 {
-	struct tcp_sock *tp = tcp_sk(sk);
+	struct inet_connection_sock *icsk = inet_csk(sk);
 	struct request_sock *acc_req;
 	struct request_sock *req;
 
-	tcp_delete_keepalive_timer(sk);
+	inet_csk_delete_keepalive_timer(sk);
 
 	/* make all the listen_opt local to us */
-	acc_req = reqsk_queue_yank_acceptq(&tp->accept_queue);
+	acc_req = reqsk_queue_yank_acceptq(&icsk->icsk_accept_queue);
 
 	/* Following specs, it would be better either to send FIN
 	 * (and enter FIN-WAIT-1, it is normal close)
@@ -512,7 +512,7 @@ static void tcp_listen_stop (struct sock *sk)
 	 * To be honest, we are not able to make either
 	 * of the variants now.			--ANK
 	 */
-	reqsk_queue_destroy(&tp->accept_queue);
+	reqsk_queue_destroy(&icsk->icsk_accept_queue);
 
 	while ((req = acc_req) != NULL) {
 		struct sock *child = req->sk;
@@ -1039,20 +1039,21 @@ static void cleanup_rbuf(struct sock *sk, int copied)
 	BUG_TRAP(!skb || before(tp->copied_seq, TCP_SKB_CB(skb)->end_seq));
 #endif
 
-	if (tcp_ack_scheduled(tp)) {
+	if (inet_csk_ack_scheduled(sk)) {
+		const struct inet_connection_sock *icsk = inet_csk(sk);
 		   /* Delayed ACKs frequently hit locked sockets during bulk
 		    * receive. */
-		if (tp->ack.blocked ||
+		if (icsk->icsk_ack.blocked ||
 		    /* Once-per-two-segments ACK was not sent by tcp_input.c */
-		    tp->rcv_nxt - tp->rcv_wup > tp->ack.rcv_mss ||
+		    tp->rcv_nxt - tp->rcv_wup > icsk->icsk_ack.rcv_mss ||
 		    /*
 		     * If this read emptied read buffer, we send ACK, if
 		     * connection is not bidirectional, user drained
 		     * receive buffer and there was a small segment
 		     * in queue.
 		     */
-		    (copied > 0 && (tp->ack.pending & TCP_ACK_PUSHED) &&
-		     !tp->ack.pingpong && !atomic_read(&sk->sk_rmem_alloc)))
+		    (copied > 0 && (icsk->icsk_ack.pending & ICSK_ACK_PUSHED) &&
+		     !icsk->icsk_ack.pingpong && !atomic_read(&sk->sk_rmem_alloc)))
 			time_to_ack = 1;
 	}
 
@@ -1569,7 +1570,7 @@ void tcp_destroy_sock(struct sock *sk)
 	BUG_TRAP(sk_unhashed(sk));
 
 	/* If it has not 0 inet_sk(sk)->num, it must be bound */
-	BUG_TRAP(!inet_sk(sk)->num || inet_sk(sk)->bind_hash);
+	BUG_TRAP(!inet_sk(sk)->num || inet_csk(sk)->icsk_bind_hash);
 
 	sk->sk_prot->destroy(sk);
 
@@ -1698,10 +1699,10 @@ adjudge_to_death:
 			tcp_send_active_reset(sk, GFP_ATOMIC);
 			NET_INC_STATS_BH(LINUX_MIB_TCPABORTONLINGER);
 		} else {
-			int tmo = tcp_fin_time(tp);
+			const int tmo = tcp_fin_time(sk);
 
 			if (tmo > TCP_TIMEWAIT_LEN) {
-				tcp_reset_keepalive_timer(sk, tcp_fin_time(tp));
+				inet_csk_reset_keepalive_timer(sk, tcp_fin_time(sk));
 			} else {
 				atomic_inc(&tcp_orphan_count);
 				tcp_time_wait(sk, TCP_FIN_WAIT2, tmo);
@@ -1746,6 +1747,7 @@ static inline int tcp_need_reset(int state)
 int tcp_disconnect(struct sock *sk, int flags)
 {
 	struct inet_sock *inet = inet_sk(sk);
+	struct inet_connection_sock *icsk = inet_csk(sk);
 	struct tcp_sock *tp = tcp_sk(sk);
 	int err = 0;
 	int old_state = sk->sk_state;
@@ -1782,7 +1784,7 @@ int tcp_disconnect(struct sock *sk, int flags)
 	tp->srtt = 0;
 	if ((tp->write_seq += tp->max_window + 2) == 0)
 		tp->write_seq = 1;
-	tp->backoff = 0;
+	icsk->icsk_backoff = 0;
 	tp->snd_cwnd = 2;
 	tp->probes_out = 0;
 	tp->packets_out = 0;
@@ -1790,13 +1792,13 @@ int tcp_disconnect(struct sock *sk, int flags)
 	tp->snd_cwnd_cnt = 0;
 	tcp_set_ca_state(tp, TCP_CA_Open);
 	tcp_clear_retrans(tp);
-	tcp_delack_init(tp);
+	inet_csk_delack_init(sk);
 	sk->sk_send_head = NULL;
 	tp->rx_opt.saw_tstamp = 0;
 	tcp_sack_reset(&tp->rx_opt);
 	__sk_dst_reset(sk);
 
-	BUG_TRAP(!inet->num || inet->bind_hash);
+	BUG_TRAP(!inet->num || icsk->icsk_bind_hash);
 
 	sk->sk_error_report(sk);
 	return err;
@@ -1808,7 +1810,7 @@ int tcp_disconnect(struct sock *sk, int flags)
  */
 static int wait_for_connect(struct sock *sk, long timeo)
 {
-	struct tcp_sock *tp = tcp_sk(sk);
+	struct inet_connection_sock *icsk = inet_csk(sk);
 	DEFINE_WAIT(wait);
 	int err;
 
@@ -1830,11 +1832,11 @@ static int wait_for_connect(struct sock *sk, long timeo)
 		prepare_to_wait_exclusive(sk->sk_sleep, &wait,
 					  TASK_INTERRUPTIBLE);
 		release_sock(sk);
-		if (reqsk_queue_empty(&tp->accept_queue))
+		if (reqsk_queue_empty(&icsk->icsk_accept_queue))
 			timeo = schedule_timeout(timeo);
 		lock_sock(sk);
 		err = 0;
-		if (!reqsk_queue_empty(&tp->accept_queue))
+		if (!reqsk_queue_empty(&icsk->icsk_accept_queue))
 			break;
 		err = -EINVAL;
 		if (sk->sk_state != TCP_LISTEN)
@@ -1854,9 +1856,9 @@ static int wait_for_connect(struct sock *sk, long timeo)
  *	This will accept the next outstanding connection.
  */
 
-struct sock *tcp_accept(struct sock *sk, int flags, int *err)
+struct sock *inet_csk_accept(struct sock *sk, int flags, int *err)
 {
-	struct tcp_sock *tp = tcp_sk(sk);
+	struct inet_connection_sock *icsk = inet_csk(sk);
 	struct sock *newsk;
 	int error;
 
@@ -1870,7 +1872,7 @@ struct sock *tcp_accept(struct sock *sk, int flags, int *err)
 		goto out_err;
 
 	/* Find already established connection */
-	if (reqsk_queue_empty(&tp->accept_queue)) {
+	if (reqsk_queue_empty(&icsk->icsk_accept_queue)) {
 		long timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
 
 		/* If this is a non blocking socket don't sleep */
@@ -1883,7 +1885,7 @@ struct sock *tcp_accept(struct sock *sk, int flags, int *err)
 			goto out_err;
 	}
 
-	newsk = reqsk_queue_get_child(&tp->accept_queue, sk);
+	newsk = reqsk_queue_get_child(&icsk->icsk_accept_queue, sk);
 	BUG_TRAP(newsk->sk_state != TCP_SYN_RECV);
 out:
 	release_sock(sk);
@@ -1901,6 +1903,7 @@ int tcp_setsockopt(struct sock *sk, int level, int optname, char __user *optval,
 		   int optlen)
 {
 	struct tcp_sock *tp = tcp_sk(sk);
+	struct inet_connection_sock *icsk = inet_csk(sk);
 	int val;
 	int err = 0;
 
@@ -1999,7 +2002,7 @@ int tcp_setsockopt(struct sock *sk, int level, int optname, char __user *optval,
 					elapsed = tp->keepalive_time - elapsed;
 				else
 					elapsed = 0;
-				tcp_reset_keepalive_timer(sk, elapsed);
+				inet_csk_reset_keepalive_timer(sk, elapsed);
 			}
 		}
 		break;
@@ -2019,7 +2022,7 @@ int tcp_setsockopt(struct sock *sk, int level, int optname, char __user *optval,
 		if (val < 1 || val > MAX_TCP_SYNCNT)
 			err = -EINVAL;
 		else
-			tp->syn_retries = val;
+			icsk->icsk_syn_retries = val;
 		break;
 
 	case TCP_LINGER2:
@@ -2058,16 +2061,16 @@ int tcp_setsockopt(struct sock *sk, int level, int optname, char __user *optval,
 
 	case TCP_QUICKACK:
 		if (!val) {
-			tp->ack.pingpong = 1;
+			icsk->icsk_ack.pingpong = 1;
 		} else {
-			tp->ack.pingpong = 0;
+			icsk->icsk_ack.pingpong = 0;
 			if ((1 << sk->sk_state) &
 			    (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT) &&
-			    tcp_ack_scheduled(tp)) {
-				tp->ack.pending |= TCP_ACK_PUSHED;
+			    inet_csk_ack_scheduled(sk)) {
+				icsk->icsk_ack.pending |= ICSK_ACK_PUSHED;
 				cleanup_rbuf(sk, 1);
 				if (!(val & 1))
-					tp->ack.pingpong = 1;
+					icsk->icsk_ack.pingpong = 1;
 			}
 		}
 		break;
@@ -2084,15 +2087,16 @@ int tcp_setsockopt(struct sock *sk, int level, int optname, char __user *optval,
 void tcp_get_info(struct sock *sk, struct tcp_info *info)
 {
 	struct tcp_sock *tp = tcp_sk(sk);
+	const struct inet_connection_sock *icsk = inet_csk(sk);
 	u32 now = tcp_time_stamp;
 
 	memset(info, 0, sizeof(*info));
 
 	info->tcpi_state = sk->sk_state;
 	info->tcpi_ca_state = tp->ca_state;
-	info->tcpi_retransmits = tp->retransmits;
+	info->tcpi_retransmits = icsk->icsk_retransmits;
 	info->tcpi_probes = tp->probes_out;
-	info->tcpi_backoff = tp->backoff;
+	info->tcpi_backoff = icsk->icsk_backoff;
 
 	if (tp->rx_opt.tstamp_ok)
 		info->tcpi_options |= TCPI_OPT_TIMESTAMPS;
@@ -2107,10 +2111,10 @@ void tcp_get_info(struct sock *sk, struct tcp_info *info)
 	if (tp->ecn_flags&TCP_ECN_OK)
 		info->tcpi_options |= TCPI_OPT_ECN;
 
-	info->tcpi_rto = jiffies_to_usecs(tp->rto);
-	info->tcpi_ato = jiffies_to_usecs(tp->ack.ato);
+	info->tcpi_rto = jiffies_to_usecs(icsk->icsk_rto);
+	info->tcpi_ato = jiffies_to_usecs(icsk->icsk_ack.ato);
 	info->tcpi_snd_mss = tp->mss_cache;
-	info->tcpi_rcv_mss = tp->ack.rcv_mss;
+	info->tcpi_rcv_mss = icsk->icsk_ack.rcv_mss;
 
 	info->tcpi_unacked = tp->packets_out;
 	info->tcpi_sacked = tp->sacked_out;
@@ -2119,7 +2123,7 @@ void tcp_get_info(struct sock *sk, struct tcp_info *info)
 	info->tcpi_fackets = tp->fackets_out;
 
 	info->tcpi_last_data_sent = jiffies_to_msecs(now - tp->lsndtime);
-	info->tcpi_last_data_recv = jiffies_to_msecs(now - tp->ack.lrcvtime);
+	info->tcpi_last_data_recv = jiffies_to_msecs(now - icsk->icsk_ack.lrcvtime);
 	info->tcpi_last_ack_recv = jiffies_to_msecs(now - tp->rcv_tstamp);
 
 	info->tcpi_pmtu = tp->pmtu_cookie;
@@ -2179,7 +2183,7 @@ int tcp_getsockopt(struct sock *sk, int level, int optname, char __user *optval,
 		val = tp->keepalive_probes ? : sysctl_tcp_keepalive_probes;
 		break;
 	case TCP_SYNCNT:
-		val = tp->syn_retries ? : sysctl_tcp_syn_retries;
+		val = inet_csk(sk)->icsk_syn_retries ? : sysctl_tcp_syn_retries;
 		break;
 	case TCP_LINGER2:
 		val = tp->linger2;
@@ -2209,7 +2213,7 @@ int tcp_getsockopt(struct sock *sk, int level, int optname, char __user *optval,
 		return 0;
 	}
 	case TCP_QUICKACK:
-		val = !tp->ack.pingpong;
+		val = !inet_csk(sk)->icsk_ack.pingpong;
 		break;
 
 	case TCP_CONGESTION:
@@ -2340,7 +2344,7 @@ void __init tcp_init(void)
 	tcp_register_congestion_control(&tcp_reno);
 }
 
-EXPORT_SYMBOL(tcp_accept);
+EXPORT_SYMBOL(inet_csk_accept);
 EXPORT_SYMBOL(tcp_close);
 EXPORT_SYMBOL(tcp_destroy_sock);
 EXPORT_SYMBOL(tcp_disconnect);
diff --git a/net/ipv4/tcp_diag.c b/net/ipv4/tcp_diag.c
index 60c6a797cc5..5f4c74f45e8 100644
--- a/net/ipv4/tcp_diag.c
+++ b/net/ipv4/tcp_diag.c
@@ -48,8 +48,9 @@ static struct sock *tcpnl;
 static int tcpdiag_fill(struct sk_buff *skb, struct sock *sk,
 			int ext, u32 pid, u32 seq, u16 nlmsg_flags)
 {
-	struct inet_sock *inet = inet_sk(sk);
+	const struct inet_sock *inet = inet_sk(sk);
 	struct tcp_sock *tp = tcp_sk(sk);
+	const struct inet_connection_sock *icsk = inet_csk(sk);
 	struct tcpdiagmsg *r;
 	struct nlmsghdr  *nlh;
 	struct tcp_info  *info = NULL;
@@ -129,14 +130,14 @@ static int tcpdiag_fill(struct sk_buff *skb, struct sock *sk,
 
 #define EXPIRES_IN_MS(tmo)  ((tmo-jiffies)*1000+HZ-1)/HZ
 
-	if (tp->pending == TCP_TIME_RETRANS) {
+	if (icsk->icsk_pending == ICSK_TIME_RETRANS) {
 		r->tcpdiag_timer = 1;
-		r->tcpdiag_retrans = tp->retransmits;
-		r->tcpdiag_expires = EXPIRES_IN_MS(tp->timeout);
-	} else if (tp->pending == TCP_TIME_PROBE0) {
+		r->tcpdiag_retrans = icsk->icsk_retransmits;
+		r->tcpdiag_expires = EXPIRES_IN_MS(icsk->icsk_timeout);
+	} else if (icsk->icsk_pending == ICSK_TIME_PROBE0) {
 		r->tcpdiag_timer = 4;
 		r->tcpdiag_retrans = tp->probes_out;
-		r->tcpdiag_expires = EXPIRES_IN_MS(tp->timeout);
+		r->tcpdiag_expires = EXPIRES_IN_MS(icsk->icsk_timeout);
 	} else if (timer_pending(&sk->sk_timer)) {
 		r->tcpdiag_timer = 2;
 		r->tcpdiag_retrans = tp->probes_out;
@@ -497,7 +498,7 @@ static int tcpdiag_dump_reqs(struct sk_buff *skb, struct sock *sk,
 {
 	struct tcpdiag_entry entry;
 	struct tcpdiagreq *r = NLMSG_DATA(cb->nlh);
-	struct tcp_sock *tp = tcp_sk(sk);
+	struct inet_connection_sock *icsk = inet_csk(sk);
 	struct listen_sock *lopt;
 	struct rtattr *bc = NULL;
 	struct inet_sock *inet = inet_sk(sk);
@@ -513,9 +514,9 @@ static int tcpdiag_dump_reqs(struct sk_buff *skb, struct sock *sk,
 
 	entry.family = sk->sk_family;
 
-	read_lock_bh(&tp->accept_queue.syn_wait_lock);
+	read_lock_bh(&icsk->icsk_accept_queue.syn_wait_lock);
 
-	lopt = tp->accept_queue.listen_opt;
+	lopt = icsk->icsk_accept_queue.listen_opt;
 	if (!lopt || !lopt->qlen)
 		goto out;
 
@@ -572,7 +573,7 @@ static int tcpdiag_dump_reqs(struct sk_buff *skb, struct sock *sk,
 	}
 
 out:
-	read_unlock_bh(&tp->accept_queue.syn_wait_lock);
+	read_unlock_bh(&icsk->icsk_accept_queue.syn_wait_lock);
 
 	return err;
 }
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index ffa24025cd0..8a8c5c2d90c 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -114,20 +114,21 @@ int sysctl_tcp_moderate_rcvbuf = 1;
 /* Adapt the MSS value used to make delayed ack decision to the 
  * real world.
  */ 
-static inline void tcp_measure_rcv_mss(struct tcp_sock *tp,
-				       struct sk_buff *skb)
+static inline void tcp_measure_rcv_mss(struct sock *sk,
+				       const struct sk_buff *skb)
 {
-	unsigned int len, lss;
+	struct inet_connection_sock *icsk = inet_csk(sk);
+	const unsigned int lss = icsk->icsk_ack.last_seg_size; 
+	unsigned int len;
 
-	lss = tp->ack.last_seg_size; 
-	tp->ack.last_seg_size = 0; 
+	icsk->icsk_ack.last_seg_size = 0; 
 
 	/* skb->len may jitter because of SACKs, even if peer
 	 * sends good full-sized frames.
 	 */
 	len = skb->len;
-	if (len >= tp->ack.rcv_mss) {
-		tp->ack.rcv_mss = len;
+	if (len >= icsk->icsk_ack.rcv_mss) {
+		icsk->icsk_ack.rcv_mss = len;
 	} else {
 		/* Otherwise, we make more careful check taking into account,
 		 * that SACKs block is variable.
@@ -147,41 +148,44 @@ static inline void tcp_measure_rcv_mss(struct tcp_sock *tp,
 			 * tcp header plus fixed timestamp option length.
 			 * Resulting "len" is MSS free of SACK jitter.
 			 */
-			len -= tp->tcp_header_len;
-			tp->ack.last_seg_size = len;
+			len -= tcp_sk(sk)->tcp_header_len;
+			icsk->icsk_ack.last_seg_size = len;
 			if (len == lss) {
-				tp->ack.rcv_mss = len;
+				icsk->icsk_ack.rcv_mss = len;
 				return;
 			}
 		}
-		tp->ack.pending |= TCP_ACK_PUSHED;
+		icsk->icsk_ack.pending |= ICSK_ACK_PUSHED;
 	}
 }
 
-static void tcp_incr_quickack(struct tcp_sock *tp)
+static void tcp_incr_quickack(struct sock *sk)
 {
-	unsigned quickacks = tp->rcv_wnd/(2*tp->ack.rcv_mss);
+	struct inet_connection_sock *icsk = inet_csk(sk);
+	unsigned quickacks = tcp_sk(sk)->rcv_wnd / (2 * icsk->icsk_ack.rcv_mss);
 
 	if (quickacks==0)
 		quickacks=2;
-	if (quickacks > tp->ack.quick)
-		tp->ack.quick = min(quickacks, TCP_MAX_QUICKACKS);
+	if (quickacks > icsk->icsk_ack.quick)
+		icsk->icsk_ack.quick = min(quickacks, TCP_MAX_QUICKACKS);
 }
 
-void tcp_enter_quickack_mode(struct tcp_sock *tp)
+void tcp_enter_quickack_mode(struct sock *sk)
 {
-	tcp_incr_quickack(tp);
-	tp->ack.pingpong = 0;
-	tp->ack.ato = TCP_ATO_MIN;
+	struct inet_connection_sock *icsk = inet_csk(sk);
+	tcp_incr_quickack(sk);
+	icsk->icsk_ack.pingpong = 0;
+	icsk->icsk_ack.ato = TCP_ATO_MIN;
 }
 
 /* Send ACKs quickly, if "quick" count is not exhausted
  * and the session is not interactive.
  */
 
-static __inline__ int tcp_in_quickack_mode(struct tcp_sock *tp)
+static inline int tcp_in_quickack_mode(const struct sock *sk)
 {
-	return (tp->ack.quick && !tp->ack.pingpong);
+	const struct inet_connection_sock *icsk = inet_csk(sk);
+	return icsk->icsk_ack.quick && !icsk->icsk_ack.pingpong;
 }
 
 /* Buffer size and advertised window tuning.
@@ -224,8 +228,8 @@ static void tcp_fixup_sndbuf(struct sock *sk)
  */
 
 /* Slow part of check#2. */
-static int __tcp_grow_window(struct sock *sk, struct tcp_sock *tp,
-			     struct sk_buff *skb)
+static int __tcp_grow_window(const struct sock *sk, struct tcp_sock *tp,
+			     const struct sk_buff *skb)
 {
 	/* Optimize this! */
 	int truesize = tcp_win_from_space(skb->truesize)/2;
@@ -233,7 +237,7 @@ static int __tcp_grow_window(struct sock *sk, struct tcp_sock *tp,
 
 	while (tp->rcv_ssthresh <= window) {
 		if (truesize <= skb->len)
-			return 2*tp->ack.rcv_mss;
+			return 2 * inet_csk(sk)->icsk_ack.rcv_mss;
 
 		truesize >>= 1;
 		window >>= 1;
@@ -260,7 +264,7 @@ static inline void tcp_grow_window(struct sock *sk, struct tcp_sock *tp,
 
 		if (incr) {
 			tp->rcv_ssthresh = min(tp->rcv_ssthresh + incr, tp->window_clamp);
-			tp->ack.quick |= 1;
+			inet_csk(sk)->icsk_ack.quick |= 1;
 		}
 	}
 }
@@ -325,7 +329,7 @@ static void tcp_clamp_window(struct sock *sk, struct tcp_sock *tp)
 	unsigned int app_win = tp->rcv_nxt - tp->copied_seq;
 	int ofo_win = 0;
 
-	tp->ack.quick = 0;
+	inet_csk(sk)->icsk_ack.quick = 0;
 
 	skb_queue_walk(&tp->out_of_order_queue, skb) {
 		ofo_win += skb->len;
@@ -346,8 +350,8 @@ 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 > tp->ack.rcv_mss)
-			app_win -= tp->ack.rcv_mss;
+		if (app_win > inet_csk(sk)->icsk_ack.rcv_mss)
+			app_win -= inet_csk(sk)->icsk_ack.rcv_mss;
 		app_win = max(app_win, 2U*tp->advmss);
 
 		if (!ofo_win)
@@ -415,11 +419,12 @@ new_measure:
 	tp->rcv_rtt_est.time = tcp_time_stamp;
 }
 
-static inline void tcp_rcv_rtt_measure_ts(struct tcp_sock *tp, struct sk_buff *skb)
+static inline void tcp_rcv_rtt_measure_ts(struct sock *sk, const struct sk_buff *skb)
 {
+	struct tcp_sock *tp = tcp_sk(sk);
 	if (tp->rx_opt.rcv_tsecr &&
 	    (TCP_SKB_CB(skb)->end_seq -
-	     TCP_SKB_CB(skb)->seq >= tp->ack.rcv_mss))
+	     TCP_SKB_CB(skb)->seq >= inet_csk(sk)->icsk_ack.rcv_mss))
 		tcp_rcv_rtt_update(tp, tcp_time_stamp - tp->rx_opt.rcv_tsecr, 0);
 }
 
@@ -492,41 +497,42 @@ new_measure:
  */
 static void tcp_event_data_recv(struct sock *sk, struct tcp_sock *tp, struct sk_buff *skb)
 {
+	struct inet_connection_sock *icsk = inet_csk(sk);
 	u32 now;
 
-	tcp_schedule_ack(tp);
+	inet_csk_schedule_ack(sk);
 
-	tcp_measure_rcv_mss(tp, skb);
+	tcp_measure_rcv_mss(sk, skb);
 
 	tcp_rcv_rtt_measure(tp);
 	
 	now = tcp_time_stamp;
 
-	if (!tp->ack.ato) {
+	if (!icsk->icsk_ack.ato) {
 		/* The _first_ data packet received, initialize
 		 * delayed ACK engine.
 		 */
-		tcp_incr_quickack(tp);
-		tp->ack.ato = TCP_ATO_MIN;
+		tcp_incr_quickack(sk);
+		icsk->icsk_ack.ato = TCP_ATO_MIN;
 	} else {
-		int m = now - tp->ack.lrcvtime;
+		int m = now - icsk->icsk_ack.lrcvtime;
 
 		if (m <= TCP_ATO_MIN/2) {
 			/* The fastest case is the first. */
-			tp->ack.ato = (tp->ack.ato>>1) + TCP_ATO_MIN/2;
-		} else if (m < tp->ack.ato) {
-			tp->ack.ato = (tp->ack.ato>>1) + m;
-			if (tp->ack.ato > tp->rto)
-				tp->ack.ato = tp->rto;
-		} else if (m > tp->rto) {
+			icsk->icsk_ack.ato = (icsk->icsk_ack.ato >> 1) + TCP_ATO_MIN / 2;
+		} else if (m < icsk->icsk_ack.ato) {
+			icsk->icsk_ack.ato = (icsk->icsk_ack.ato >> 1) + m;
+			if (icsk->icsk_ack.ato > icsk->icsk_rto)
+				icsk->icsk_ack.ato = icsk->icsk_rto;
+		} else if (m > icsk->icsk_rto) {
 			/* Too long gap. Apparently sender falled to
 			 * restart window, so that we send ACKs quickly.
 			 */
-			tcp_incr_quickack(tp);
+			tcp_incr_quickack(sk);
 			sk_stream_mem_reclaim(sk);
 		}
 	}
-	tp->ack.lrcvtime = now;
+	icsk->icsk_ack.lrcvtime = now;
 
 	TCP_ECN_check_ce(tp, skb);
 
@@ -611,8 +617,9 @@ static void tcp_rtt_estimator(struct tcp_sock *tp, __u32 mrtt, u32 *usrtt)
 /* Calculate rto without backoff.  This is the second half of Van Jacobson's
  * routine referred to above.
  */
-static inline void tcp_set_rto(struct tcp_sock *tp)
+static inline void tcp_set_rto(struct sock *sk)
 {
+	const struct tcp_sock *tp = tcp_sk(sk);
 	/* Old crap is replaced with new one. 8)
 	 *
 	 * More seriously:
@@ -623,7 +630,7 @@ static inline void tcp_set_rto(struct tcp_sock *tp)
 	 *    is invisible. Actually, Linux-2.4 also generates erratic
 	 *    ACKs in some curcumstances.
 	 */
-	tp->rto = (tp->srtt >> 3) + tp->rttvar;
+	inet_csk(sk)->icsk_rto = (tp->srtt >> 3) + tp->rttvar;
 
 	/* 2. Fixups made earlier cannot be right.
 	 *    If we do not estimate RTO correctly without them,
@@ -635,10 +642,10 @@ static inline void tcp_set_rto(struct tcp_sock *tp)
 /* NOTE: clamping at TCP_RTO_MIN is not required, current algo
  * guarantees that rto is higher.
  */
-static inline void tcp_bound_rto(struct tcp_sock *tp)
+static inline void tcp_bound_rto(struct sock *sk)
 {
-	if (tp->rto > TCP_RTO_MAX)
-		tp->rto = TCP_RTO_MAX;
+	if (inet_csk(sk)->icsk_rto > TCP_RTO_MAX)
+		inet_csk(sk)->icsk_rto = TCP_RTO_MAX;
 }
 
 /* Save metrics learned by this TCP session.
@@ -658,7 +665,7 @@ void tcp_update_metrics(struct sock *sk)
 	if (dst && (dst->flags&DST_HOST)) {
 		int m;
 
-		if (tp->backoff || !tp->srtt) {
+		if (inet_csk(sk)->icsk_backoff || !tp->srtt) {
 			/* This session failed to estimate rtt. Why?
 			 * Probably, no packets returned in time.
 			 * Reset our results.
@@ -801,9 +808,9 @@ static void tcp_init_metrics(struct sock *sk)
 		tp->mdev = dst_metric(dst, RTAX_RTTVAR);
 		tp->mdev_max = tp->rttvar = max(tp->mdev, TCP_RTO_MIN);
 	}
-	tcp_set_rto(tp);
-	tcp_bound_rto(tp);
-	if (tp->rto < TCP_TIMEOUT_INIT && !tp->rx_opt.saw_tstamp)
+	tcp_set_rto(sk);
+	tcp_bound_rto(sk);
+	if (inet_csk(sk)->icsk_rto < TCP_TIMEOUT_INIT && !tp->rx_opt.saw_tstamp)
 		goto reset;
 	tp->snd_cwnd = tcp_init_cwnd(tp, dst);
 	tp->snd_cwnd_stamp = tcp_time_stamp;
@@ -817,7 +824,7 @@ reset:
 	if (!tp->rx_opt.saw_tstamp && tp->srtt) {
 		tp->srtt = 0;
 		tp->mdev = tp->mdev_max = tp->rttvar = TCP_TIMEOUT_INIT;
-		tp->rto = TCP_TIMEOUT_INIT;
+		inet_csk(sk)->icsk_rto = TCP_TIMEOUT_INIT;
 	}
 }
 
@@ -1118,7 +1125,7 @@ void tcp_enter_frto(struct sock *sk)
 
 	if (tp->ca_state <= TCP_CA_Disorder ||
             tp->snd_una == tp->high_seq ||
-            (tp->ca_state == TCP_CA_Loss && !tp->retransmits)) {
+            (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);
@@ -1214,7 +1221,7 @@ void tcp_enter_loss(struct sock *sk, int how)
 
 	/* 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 && !tp->retransmits)) {
+	    (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);
@@ -1253,7 +1260,7 @@ void tcp_enter_loss(struct sock *sk, int how)
 	TCP_ECN_queue_cwr(tp);
 }
 
-static int tcp_check_sack_reneging(struct sock *sk, struct tcp_sock *tp)
+static int tcp_check_sack_reneging(struct sock *sk)
 {
 	struct sk_buff *skb;
 
@@ -1268,9 +1275,10 @@ static int tcp_check_sack_reneging(struct sock *sk, struct tcp_sock *tp)
 		NET_INC_STATS_BH(LINUX_MIB_TCPSACKRENEGING);
 
 		tcp_enter_loss(sk, 1);
-		tp->retransmits++;
+		inet_csk(sk)->icsk_retransmits++;
 		tcp_retransmit_skb(sk, skb_peek(&sk->sk_write_queue));
-		tcp_reset_xmit_timer(sk, TCP_TIME_RETRANS, tp->rto);
+		inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS,
+					  inet_csk(sk)->icsk_rto);
 		return 1;
 	}
 	return 0;
@@ -1281,15 +1289,15 @@ static inline int tcp_fackets_out(struct tcp_sock *tp)
 	return IsReno(tp) ? tp->sacked_out+1 : tp->fackets_out;
 }
 
-static inline int tcp_skb_timedout(struct tcp_sock *tp, struct sk_buff *skb)
+static inline int tcp_skb_timedout(struct sock *sk, struct sk_buff *skb)
 {
-	return (tcp_time_stamp - TCP_SKB_CB(skb)->when > tp->rto);
+	return (tcp_time_stamp - TCP_SKB_CB(skb)->when > inet_csk(sk)->icsk_rto);
 }
 
 static inline int tcp_head_timedout(struct sock *sk, struct tcp_sock *tp)
 {
 	return tp->packets_out &&
-	       tcp_skb_timedout(tp, skb_peek(&sk->sk_write_queue));
+	       tcp_skb_timedout(sk, skb_peek(&sk->sk_write_queue));
 }
 
 /* Linux NewReno/SACK/FACK/ECN state machine.
@@ -1509,7 +1517,7 @@ static void tcp_update_scoreboard(struct sock *sk, struct tcp_sock *tp)
 		struct sk_buff *skb;
 
 		sk_stream_for_retrans_queue(skb, sk) {
-			if (tcp_skb_timedout(tp, skb) &&
+			if (tcp_skb_timedout(sk, skb) &&
 			    !(TCP_SKB_CB(skb)->sacked&TCPCB_TAGBITS)) {
 				TCP_SKB_CB(skb)->sacked |= TCPCB_LOST;
 				tp->lost_out += tcp_skb_pcount(skb);
@@ -1676,7 +1684,7 @@ static int tcp_try_undo_loss(struct sock *sk, struct tcp_sock *tp)
 		tp->left_out = tp->sacked_out;
 		tcp_undo_cwr(tp, 1);
 		NET_INC_STATS_BH(LINUX_MIB_TCPLOSSUNDO);
-		tp->retransmits = 0;
+		inet_csk(sk)->icsk_retransmits = 0;
 		tp->undo_marker = 0;
 		if (!IsReno(tp))
 			tcp_set_ca_state(tp, TCP_CA_Open);
@@ -1750,7 +1758,7 @@ tcp_fastretrans_alert(struct sock *sk, u32 prior_snd_una,
 		tp->prior_ssthresh = 0;
 
 	/* B. In all the states check for reneging SACKs. */
-	if (tp->sacked_out && tcp_check_sack_reneging(sk, tp))
+	if (tp->sacked_out && tcp_check_sack_reneging(sk))
 		return;
 
 	/* C. Process data loss notification, provided it is valid. */
@@ -1774,7 +1782,7 @@ tcp_fastretrans_alert(struct sock *sk, u32 prior_snd_una,
 	} else if (!before(tp->snd_una, tp->high_seq)) {
 		switch (tp->ca_state) {
 		case TCP_CA_Loss:
-			tp->retransmits = 0;
+			inet_csk(sk)->icsk_retransmits = 0;
 			if (tcp_try_undo_recovery(sk, tp))
 				return;
 			break;
@@ -1824,7 +1832,7 @@ tcp_fastretrans_alert(struct sock *sk, u32 prior_snd_una,
 		break;
 	case TCP_CA_Loss:
 		if (flag&FLAG_DATA_ACKED)
-			tp->retransmits = 0;
+			inet_csk(sk)->icsk_retransmits = 0;
 		if (!tcp_try_undo_loss(sk, tp)) {
 			tcp_moderate_cwnd(tp);
 			tcp_xmit_retransmit_queue(sk);
@@ -1881,10 +1889,8 @@ tcp_fastretrans_alert(struct sock *sk, u32 prior_snd_una,
 /* Read draft-ietf-tcplw-high-performance before mucking
  * with this code. (Superceeds RFC1323)
  */
-static void tcp_ack_saw_tstamp(struct tcp_sock *tp, u32 *usrtt, int flag)
+static void tcp_ack_saw_tstamp(struct sock *sk, u32 *usrtt, int flag)
 {
-	__u32 seq_rtt;
-
 	/* RTTM Rule: A TSecr value received in a segment is used to
 	 * update the averaged RTT measurement only if the segment
 	 * acknowledges some new data, i.e., only if it advances the
@@ -1900,14 +1906,15 @@ static void tcp_ack_saw_tstamp(struct tcp_sock *tp, u32 *usrtt, int flag)
 	 * answer arrives rto becomes 120 seconds! If at least one of segments
 	 * in window is lost... Voila.	 			--ANK (010210)
 	 */
-	seq_rtt = tcp_time_stamp - tp->rx_opt.rcv_tsecr;
+	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_set_rto(tp);
-	tp->backoff = 0;
-	tcp_bound_rto(tp);
+	tcp_set_rto(sk);
+	inet_csk(sk)->icsk_backoff = 0;
+	tcp_bound_rto(sk);
 }
 
-static void tcp_ack_no_tstamp(struct tcp_sock *tp, u32 seq_rtt, u32 *usrtt, int flag)
+static void tcp_ack_no_tstamp(struct sock *sk, u32 seq_rtt, u32 *usrtt, int flag)
 {
 	/* We don't have a timestamp. Can only use
 	 * packets that are not retransmitted to determine
@@ -1921,20 +1928,21 @@ static void tcp_ack_no_tstamp(struct tcp_sock *tp, u32 seq_rtt, u32 *usrtt, int
 	if (flag & FLAG_RETRANS_DATA_ACKED)
 		return;
 
-	tcp_rtt_estimator(tp, seq_rtt, usrtt);
-	tcp_set_rto(tp);
-	tp->backoff = 0;
-	tcp_bound_rto(tp);
+	tcp_rtt_estimator(tcp_sk(sk), seq_rtt, usrtt);
+	tcp_set_rto(sk);
+	inet_csk(sk)->icsk_backoff = 0;
+	tcp_bound_rto(sk);
 }
 
-static inline void tcp_ack_update_rtt(struct tcp_sock *tp,
-				      int flag, s32 seq_rtt, u32 *usrtt)
+static inline void tcp_ack_update_rtt(struct sock *sk, const int flag,
+				      const s32 seq_rtt, u32 *usrtt)
 {
+	const struct tcp_sock *tp = tcp_sk(sk);
 	/* Note that peer MAY send zero echo. In this case it is ignored. (rfc1323) */
 	if (tp->rx_opt.saw_tstamp && tp->rx_opt.rcv_tsecr)
-		tcp_ack_saw_tstamp(tp, usrtt, flag);
+		tcp_ack_saw_tstamp(sk, usrtt, flag);
 	else if (seq_rtt >= 0)
-		tcp_ack_no_tstamp(tp, seq_rtt, usrtt, flag);
+		tcp_ack_no_tstamp(sk, seq_rtt, usrtt, flag);
 }
 
 static inline void tcp_cong_avoid(struct tcp_sock *tp, u32 ack, u32 rtt,
@@ -1951,9 +1959,9 @@ static inline void tcp_cong_avoid(struct tcp_sock *tp, u32 ack, u32 rtt,
 static inline void tcp_ack_packets_out(struct sock *sk, struct tcp_sock *tp)
 {
 	if (!tp->packets_out) {
-		tcp_clear_xmit_timer(sk, TCP_TIME_RETRANS);