[IP_SOCKGLUE]: Remove most of the tcp specific calls

As DCCP needs to be called in the same spots.

Now we have a member in inet_sock (is_icsk), set at sock creation time from
struct inet_protosw->flags (if INET_PROTOSW_ICSK is set, like for TCP and
DCCP) to see if a struct sock instance is a inet_connection_sock for places
like the ones in ip_sockglue.c (v4 and v6) where we previously were looking if
sk_type was SOCK_STREAM, that is insufficient because we now use the same code
for DCCP, that has sk_type SOCK_DCCP.

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

net/dccp/diag.c

@@ -28,7 +28,7 @@ static void dccp_get_info(struct sock *sk, struct tcp_info *info)
 	info->tcpi_retransmits	= icsk->icsk_retransmits;
 	info->tcpi_probes	= icsk->icsk_probes_out;
 	info->tcpi_backoff	= icsk->icsk_backoff;
-	info->tcpi_pmtu		= dp->dccps_pmtu_cookie;
+	info->tcpi_pmtu		= icsk->icsk_pmtu_cookie;
 
 	if (dp->dccps_options.dccpo_send_ack_vector)
 		info->tcpi_options |= TCPI_OPT_SACK;

net/dccp/input.c

@@ -311,7 +311,7 @@ static int dccp_rcv_request_sent_state_process(struct sock *sk,
 			goto out_invalid_packet;
 		}
 
-		dccp_sync_mss(sk, dp->dccps_pmtu_cookie);
+		dccp_sync_mss(sk, icsk->icsk_pmtu_cookie);
 
 		/*
 		 *    Step 10: Process REQUEST state (second part)

net/dccp/ipv4.c

@@ -104,9 +104,9 @@ int dccp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
 	inet->dport = usin->sin_port;
 	inet->daddr = daddr;
 
-	dp->dccps_ext_header_len = 0;
+	inet_csk(sk)->icsk_ext_hdr_len = 0;
 	if (inet->opt != NULL)
-		dp->dccps_ext_header_len = inet->opt->optlen;
+		inet_csk(sk)->icsk_ext_hdr_len = inet->opt->optlen;
 	/*
 	 * Socket identity is still unknown (sport may be zero).
 	 * However we set state to DCCP_REQUESTING and not releasing socket
@@ -191,7 +191,7 @@ static inline void dccp_do_pmtu_discovery(struct sock *sk,
 	mtu = dst_mtu(dst);
 
 	if (inet->pmtudisc != IP_PMTUDISC_DONT &&
-	    dp->dccps_pmtu_cookie > mtu) {
+	    inet_csk(sk)->icsk_pmtu_cookie > mtu) {
 		dccp_sync_mss(sk, mtu);
 
 		/*
@@ -1051,6 +1051,7 @@ struct inet_connection_sock_af_ops dccp_ipv4_af_ops = {
 int dccp_v4_init_sock(struct sock *sk)
 {
 	struct dccp_sock *dp = dccp_sk(sk);
+	struct inet_connection_sock *icsk = inet_csk(sk);
 	static int dccp_ctl_socket_init = 1;
 
 	dccp_options_init(&dp->dccps_options);
@@ -1090,10 +1091,11 @@ int dccp_v4_init_sock(struct sock *sk)
 		dccp_ctl_socket_init = 0;
 
 	dccp_init_xmit_timers(sk);
-	inet_csk(sk)->icsk_rto = DCCP_TIMEOUT_INIT;
+	icsk->icsk_rto = DCCP_TIMEOUT_INIT;
 	sk->sk_state = DCCP_CLOSED;
 	sk->sk_write_space = dccp_write_space;
-	inet_csk(sk)->icsk_af_ops = &dccp_ipv4_af_ops;
+	icsk->icsk_af_ops = &dccp_ipv4_af_ops;
+	icsk->icsk_sync_mss = dccp_sync_mss;
 	dp->dccps_mss_cache = 536;
 	dp->dccps_role = DCCP_ROLE_UNDEFINED;
 	dp->dccps_service = DCCP_SERVICE_INVALID_VALUE;

net/dccp/ipv6.c

@@ -88,6 +88,7 @@ static int dccp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
 			   int addr_len)
 {
 	struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr;
+	struct inet_connection_sock *icsk = inet_csk(sk);
 	struct inet_sock *inet = inet_sk(sk);
 	struct ipv6_pinfo *np = inet6_sk(sk);
 	struct dccp_sock *dp = dccp_sk(sk);
@@ -158,7 +159,7 @@ static int dccp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
 	 */
 
 	if (addr_type == IPV6_ADDR_MAPPED) {
-		u32 exthdrlen = dp->dccps_ext_header_len;
+		u32 exthdrlen = icsk->icsk_ext_hdr_len;
 		struct sockaddr_in sin;
 
 		SOCK_DEBUG(sk, "connect: ipv4 mapped\n");
@@ -170,14 +171,14 @@ static int dccp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
 		sin.sin_port = usin->sin6_port;
 		sin.sin_addr.s_addr = usin->sin6_addr.s6_addr32[3];
 
-		inet_csk(sk)->icsk_af_ops = &dccp_ipv6_mapped;
+		icsk->icsk_af_ops = &dccp_ipv6_mapped;
 		sk->sk_backlog_rcv = dccp_v4_do_rcv;
 
 		err = dccp_v4_connect(sk, (struct sockaddr *)&sin, sizeof(sin));
 
 		if (err) {
-			dp->dccps_ext_header_len = exthdrlen;
-			inet_csk(sk)->icsk_af_ops = &dccp_ipv6_af_ops;
+			icsk->icsk_ext_hdr_len = exthdrlen;
+			icsk->icsk_af_ops = &dccp_ipv6_af_ops;
 			sk->sk_backlog_rcv = dccp_v6_do_rcv;
 			goto failure;
 		} else {
@@ -227,9 +228,10 @@ static int dccp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
 
 	ip6_dst_store(sk, dst, NULL);
 
-	dp->dccps_ext_header_len = 0;
+	icsk->icsk_ext_hdr_len = 0;
 	if (np->opt)
-		dp->dccps_ext_header_len = np->opt->opt_flen + np->opt->opt_nflen;
+		icsk->icsk_ext_hdr_len = (np->opt->opt_flen +
+					  np->opt->opt_nflen);
 
 	inet->dport = usin->sin6_port;
 
@@ -292,7 +294,6 @@ static void dccp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 	np = inet6_sk(sk);
 
 	if (type == ICMPV6_PKT_TOOBIG) {
-		struct dccp_sock *dp = dccp_sk(sk);
 		struct dst_entry *dst = NULL;
 
 		if (sock_owned_by_user(sk))
@@ -332,7 +333,7 @@ static void dccp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 		} else
 			dst_hold(dst);
 
-		if (dp->dccps_pmtu_cookie > dst_mtu(dst)) {
+		if (inet_csk(sk)->icsk_pmtu_cookie > dst_mtu(dst)) {
 			dccp_sync_mss(sk, dst_mtu(dst));
 		} /* else let the usual retransmit timer handle it */
 		dst_release(dst);
@@ -808,7 +809,7 @@ static struct sock *dccp_v6_request_recv_sock(struct sock *sk,
 		   worked with IPv6 icsk.icsk_af_ops.
 		   Sync it now.
 		 */
-		dccp_sync_mss(newsk, newdp->dccps_pmtu_cookie);
+		dccp_sync_mss(newsk, inet_csk(newsk)->icsk_pmtu_cookie);
 
 		return newsk;
 	}
@@ -916,10 +917,10 @@ static struct sock *dccp_v6_request_recv_sock(struct sock *sk,
 			sock_kfree_s(sk, opt, opt->tot_len);
 	}
 
-	newdp->dccps_ext_header_len = 0;
+	inet_csk(newsk)->icsk_ext_hdr_len = 0;
 	if (newnp->opt)
-		newdp->dccps_ext_header_len = newnp->opt->opt_nflen +
-					      newnp->opt->opt_flen;
+		inet_csk(newsk)->icsk_ext_hdr_len = (newnp->opt->opt_nflen +
+						     newnp->opt->opt_flen);
 
 	dccp_sync_mss(newsk, dst_mtu(dst));
 
@@ -1230,6 +1231,7 @@ static struct inet_protosw dccp_v6_protosw = {
 	.prot		= &dccp_v6_prot,
 	.ops		= &inet6_dccp_ops,
 	.capability	= -1,
+	.flags		= INET_PROTOSW_ICSK,
 };
 
 static int __init dccp_v6_init(void)

net/dccp/output.c

@@ -134,12 +134,13 @@ static int dccp_transmit_skb(struct sock *sk, struct sk_buff *skb)
 
 unsigned int dccp_sync_mss(struct sock *sk, u32 pmtu)
 {
+	struct inet_connection_sock *icsk = inet_csk(sk);
 	struct dccp_sock *dp = dccp_sk(sk);
-	int mss_now = (pmtu - inet_csk(sk)->icsk_af_ops->net_header_len -
+	int mss_now = (pmtu - icsk->icsk_af_ops->net_header_len -
 		       sizeof(struct dccp_hdr) - sizeof(struct dccp_hdr_ext));
 
 	/* Now subtract optional transport overhead */
-	mss_now -= dp->dccps_ext_header_len;
+	mss_now -= icsk->icsk_ext_hdr_len;
 
 	/*
 	 * FIXME: this should come from the CCID infrastructure, where, say,
@@ -152,7 +153,7 @@ unsigned int dccp_sync_mss(struct sock *sk, u32 pmtu)
 	mss_now -= ((5 + 6 + 10 + 6 + 6 + 6 + 3) / 4) * 4;
 
 	/* And store cached results */
-	dp->dccps_pmtu_cookie = pmtu;
+	icsk->icsk_pmtu_cookie = pmtu;
 	dp->dccps_mss_cache = mss_now;
 
 	return mss_now;

net/dccp/proto.c

@@ -712,7 +712,7 @@ static struct inet_protosw dccp_v4_protosw = {
 	.ops		= &inet_dccp_ops,
 	.capability	= -1,
 	.no_check	= 0,
-	.flags		= 0,
+	.flags		= INET_PROTOSW_ICSK,
 };
 
 /*