[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>

6 files changed, 30 insertions, 29 deletions

diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index d368cf249000..617e858beff1 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -302,6 +302,7 @@ lookup_protocol:
                 sk->sk_reuse = 1;
 
         inet = inet_sk(sk);
+        inet->is_icsk = INET_PROTOSW_ICSK & answer_flags;
 
         if (SOCK_RAW == sock->type) {
                 inet->num = protocol;
@@ -869,7 +870,8 @@ static struct inet_protosw inetsw_array[] =
                 .ops =        &inet_stream_ops,
                 .capability = -1,
                 .no_check =   0,
-                .flags =      INET_PROTOSW_PERMANENT,
+                .flags =      INET_PROTOSW_PERMANENT |
+                              INET_PROTOSW_ICSK,
         },
 
         {
diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
index 4f2d87257309..add019c746f8 100644
--- a/net/ipv4/ip_sockglue.c
+++ b/net/ipv4/ip_sockglue.c
@@ -29,8 +29,7 @@
 #include <net/sock.h>
 #include <net/ip.h>
 #include <net/icmp.h>
-#include <net/tcp.h>
-#include <linux/tcp.h>
+#include <net/tcp_states.h>
 #include <linux/udp.h>
 #include <linux/igmp.h>
 #include <linux/netfilter.h>
@@ -427,8 +426,8 @@ int ip_setsockopt(struct sock *sk, int level, int optname, char __user *optval,
                         err = ip_options_get_from_user(&opt, optval, optlen);
                         if (err)
                                 break;
-                        if (sk->sk_type == SOCK_STREAM) {
-                                struct tcp_sock *tp = tcp_sk(sk);
+                        if (inet->is_icsk) {
+                                struct inet_connection_sock *icsk = inet_csk(sk);
 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
                                 if (sk->sk_family == PF_INET ||
                                     (!((1 << sk->sk_state) &
@@ -436,10 +435,10 @@ int ip_setsockopt(struct sock *sk, int level, int optname, char __user *optval,
                                      inet->daddr != LOOPBACK4_IPV6)) {
 #endif
                                         if (inet->opt)
-                                                tp->ext_header_len -= inet->opt->optlen;
+                                                icsk->icsk_ext_hdr_len -= inet->opt->optlen;
                                         if (opt)
-                                                tp->ext_header_len += opt->optlen;
-                                        tcp_sync_mss(sk, tp->pmtu_cookie);
+                                                icsk->icsk_ext_hdr_len += opt->optlen;
+                                        icsk->icsk_sync_mss(sk, icsk->icsk_pmtu_cookie);
 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
                                 }
 #endif
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index eacfe6a3442c..00aa80e93243 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -1914,7 +1914,7 @@ void tcp_get_info(struct sock *sk, struct tcp_info *info)
         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;
+        info->tcpi_pmtu = icsk->icsk_pmtu_cookie;
         info->tcpi_rcv_ssthresh = tp->rcv_ssthresh;
         info->tcpi_rtt = jiffies_to_usecs(tp->srtt)>>3;
         info->tcpi_rttvar = jiffies_to_usecs(tp->mdev)>>2;
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 7de6184d4bd8..981d1203b152 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -2342,7 +2342,7 @@ static int tcp_ack_update_window(struct sock *sk, struct tcp_sock *tp,
 
                         if (nwin > tp->max_window) {
                                 tp->max_window = nwin;
-                                tcp_sync_mss(sk, tp->pmtu_cookie);
+                                tcp_sync_mss(sk, inet_csk(sk)->icsk_pmtu_cookie);
                         }
                 }
         }
@@ -3967,12 +3967,12 @@ static int tcp_rcv_synsent_state_process(struct sock *sk, struct sk_buff *skb,
                                          struct tcphdr *th, unsigned len)
 {
         struct tcp_sock *tp = tcp_sk(sk);
+        struct inet_connection_sock *icsk = inet_csk(sk);
         int saved_clamp = tp->rx_opt.mss_clamp;
 
         tcp_parse_options(skb, &tp->rx_opt, 0);
 
         if (th->ack) {
-                struct inet_connection_sock *icsk;
                 /* rfc793:
                  * "If the state is SYN-SENT then
                  *    first check the ACK bit
@@ -4061,7 +4061,7 @@ static int tcp_rcv_synsent_state_process(struct sock *sk, struct sk_buff *skb,
                 if (tp->rx_opt.sack_ok && sysctl_tcp_fack)
                         tp->rx_opt.sack_ok |= 2;
 
-                tcp_sync_mss(sk, tp->pmtu_cookie);
+                tcp_sync_mss(sk, icsk->icsk_pmtu_cookie);
                 tcp_initialize_rcv_mss(sk);
 
                 /* Remember, tcp_poll() does not lock socket!
@@ -4071,8 +4071,6 @@ static int tcp_rcv_synsent_state_process(struct sock *sk, struct sk_buff *skb,
                 mb();
                 tcp_set_state(sk, TCP_ESTABLISHED);
 
-                icsk = inet_csk(sk);
-
                 /* Make sure socket is routed, for correct metrics.  */
                 icsk->icsk_af_ops->rebuild_header(sk);
 
@@ -4173,7 +4171,7 @@ discard:
                 if (tp->ecn_flags&TCP_ECN_OK)
                         sock_set_flag(sk, SOCK_NO_LARGESEND);
 
-                tcp_sync_mss(sk, tp->pmtu_cookie);
+                tcp_sync_mss(sk, icsk->icsk_pmtu_cookie);
                 tcp_initialize_rcv_mss(sk);
 
 
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index c2fe61becd61..9b62d80bb20f 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -220,9 +220,9 @@ int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
         inet->dport = usin->sin_port;
         inet->daddr = daddr;
 
-        tp->ext_header_len = 0;
+        inet_csk(sk)->icsk_ext_hdr_len = 0;
         if (inet->opt)
-                tp->ext_header_len = inet->opt->optlen;
+                inet_csk(sk)->icsk_ext_hdr_len = inet->opt->optlen;
 
         tp->rx_opt.mss_clamp = 536;
 
@@ -275,7 +275,6 @@ static inline void do_pmtu_discovery(struct sock *sk, struct iphdr *iph,
 {
         struct dst_entry *dst;
         struct inet_sock *inet = inet_sk(sk);
-        struct tcp_sock *tp = tcp_sk(sk);
 
         /* We are not interested in TCP_LISTEN and open_requests (SYN-ACKs
          * send out by Linux are always <576bytes so they should go through
@@ -304,7 +303,7 @@ static inline void do_pmtu_discovery(struct sock *sk, struct iphdr *iph,
         mtu = dst_mtu(dst);
 
         if (inet->pmtudisc != IP_PMTUDISC_DONT &&
-            tp->pmtu_cookie > mtu) {
+            inet_csk(sk)->icsk_pmtu_cookie > mtu) {
                 tcp_sync_mss(sk, mtu);
 
                 /* Resend the TCP packet because it's
@@ -895,9 +894,9 @@ struct sock *tcp_v4_syn_recv_sock(struct sock *sk, struct sk_buff *skb,
         ireq->opt             = NULL;
         newinet->mc_index     = inet_iif(skb);
         newinet->mc_ttl       = skb->nh.iph->ttl;
-        newtp->ext_header_len = 0;
+        inet_csk(newsk)->icsk_ext_hdr_len = 0;
         if (newinet->opt)
-                newtp->ext_header_len = newinet->opt->optlen;
+                inet_csk(newsk)->icsk_ext_hdr_len = newinet->opt->optlen;
         newinet->id = newtp->write_seq ^ jiffies;
 
         tcp_sync_mss(newsk, dst_mtu(dst));
@@ -1266,6 +1265,7 @@ static int tcp_v4_init_sock(struct sock *sk)
         sock_set_flag(sk, SOCK_USE_WRITE_QUEUE);
 
         icsk->icsk_af_ops = &ipv4_specific;
+        icsk->icsk_sync_mss = tcp_sync_mss;
 
         sk->sk_sndbuf = sysctl_tcp_wmem[1];
         sk->sk_rcvbuf = sysctl_tcp_rmem[1];
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index af1946c52c37..3a0a914de917 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -621,7 +621,7 @@ int tcp_trim_head(struct sock *sk, struct sk_buff *skb, u32 len)
    It is minimum of user_mss and mss received with SYN.
    It also does not include TCP options.
 
-   tp->pmtu_cookie is last pmtu, seen by this function.
+   inet_csk(sk)->icsk_pmtu_cookie is last pmtu, seen by this function.
 
    tp->mss_cache is current effective sending mss, including
    all tcp options except for SACKs. It is evaluated,
@@ -631,17 +631,18 @@ int tcp_trim_head(struct sock *sk, struct sk_buff *skb, u32 len)
    NOTE1. rfc1122 clearly states that advertised MSS
    DOES NOT include either tcp or ip options.
 
-   NOTE2. tp->pmtu_cookie and tp->mss_cache are READ ONLY outside
-   this function.                       --ANK (980731)
+   NOTE2. inet_csk(sk)->icsk_pmtu_cookie and tp->mss_cache
+   are READ ONLY outside this function.         --ANK (980731)
  */
 
 unsigned int tcp_sync_mss(struct sock *sk, u32 pmtu)
 {
         struct tcp_sock *tp = tcp_sk(sk);
+        struct inet_connection_sock *icsk = inet_csk(sk);
         /* Calculate base mss without TCP options:
            It is MMS_S - sizeof(tcphdr) of rfc1122
          */
-        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 tcphdr));
 
         /* Clamp it (mss_clamp does not include tcp options) */
@@ -649,7 +650,7 @@ unsigned int tcp_sync_mss(struct sock *sk, u32 pmtu)
                 mss_now = tp->rx_opt.mss_clamp;
 
         /* Now subtract optional transport overhead */
-        mss_now -= tp->ext_header_len;
+        mss_now -= icsk->icsk_ext_hdr_len;
 
         /* Then reserve room for full set of TCP options and 8 bytes of data */
         if (mss_now < 48)
@@ -663,7 +664,7 @@ unsigned int tcp_sync_mss(struct sock *sk, u32 pmtu)
                 mss_now = max((tp->max_window>>1), 68U - tp->tcp_header_len);
 
         /* And store cached results */
-        tp->pmtu_cookie = pmtu;
+        icsk->icsk_pmtu_cookie = pmtu;
         tp->mss_cache = mss_now;
 
         return mss_now;
@@ -693,7 +694,7 @@ unsigned int tcp_current_mss(struct sock *sk, int large_allowed)
 
         if (dst) {
                 u32 mtu = dst_mtu(dst);
-                if (mtu != tp->pmtu_cookie)
+                if (mtu != inet_csk(sk)->icsk_pmtu_cookie)
                         mss_now = tcp_sync_mss(sk, mtu);
         }
 
@@ -706,7 +707,8 @@ unsigned int tcp_current_mss(struct sock *sk, int large_allowed)
         if (doing_tso) {
                 xmit_size_goal = (65535 -
                                   inet_csk(sk)->icsk_af_ops->net_header_len -
-                                  tp->ext_header_len - tp->tcp_header_len);
+                                  inet_csk(sk)->icsk_ext_hdr_len -
+                                  tp->tcp_header_len);
 
                 if (tp->max_window &&
                     (xmit_size_goal > (tp->max_window >> 1)))