inet: Turn ->remember_stamp into ->get_peer in connection AF ops.
David S. Miller [Mon, 29 Nov 2010 21:37:14 +0000 (13:37 -0800)]
Then we can make a completely generic tcp_remember_stamp()
that uses ->get_peer() as a helper, minimizing the AF specific
code and minimizing the eventual code duplication when we implement
the ipv6 side of TW recycling.

Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/inet_connection_sock.h
include/net/tcp.h
net/ipv4/tcp_ipv4.c
net/ipv4/tcp_minisocks.c
net/ipv6/tcp_ipv6.c

index e4f494b..6c93a56 100644 (file)
@@ -43,7 +43,7 @@ struct inet_connection_sock_af_ops {
        struct sock *(*syn_recv_sock)(struct sock *sk, struct sk_buff *skb,
                                      struct request_sock *req,
                                      struct dst_entry *dst);
-       int         (*remember_stamp)(struct sock *sk);
+       struct inet_peer *(*get_peer)(struct sock *sk, bool *release_it);
        u16         net_header_len;
        u16         sockaddr_len;
        int         (*setsockopt)(struct sock *sk, int level, int optname, 
index e36c874..3e23964 100644 (file)
@@ -312,7 +312,7 @@ extern void tcp_shutdown (struct sock *sk, int how);
 
 extern int tcp_v4_rcv(struct sk_buff *skb);
 
-extern int tcp_v4_remember_stamp(struct sock *sk);
+extern struct inet_peer *tcp_v4_get_peer(struct sock *sk, bool *release_it);
 extern int tcp_v4_tw_remember_stamp(struct inet_timewait_sock *tw);
 extern int tcp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
                       size_t size);
index 00285fc..0ddf819 100644 (file)
@@ -1763,44 +1763,25 @@ do_time_wait:
        goto discard_it;
 }
 
-/* VJ's idea. Save last timestamp seen from this destination
- * and hold it at least for normal timewait interval to use for duplicate
- * segment detection in subsequent connections, before they enter synchronized
- * state.
- */
-
-int tcp_v4_remember_stamp(struct sock *sk)
+struct inet_peer *tcp_v4_get_peer(struct sock *sk, bool *release_it)
 {
+       struct rtable *rt = (struct rtable *) __sk_dst_get(sk);
        struct inet_sock *inet = inet_sk(sk);
-       struct tcp_sock *tp = tcp_sk(sk);
-       struct rtable *rt = (struct rtable *)__sk_dst_get(sk);
-       struct inet_peer *peer = NULL;
-       int release_it = 0;
+       struct inet_peer *peer;
 
        if (!rt || rt->rt_dst != inet->inet_daddr) {
                peer = inet_getpeer_v4(inet->inet_daddr, 1);
-               release_it = 1;
+               *release_it = true;
        } else {
                if (!rt->peer)
                        rt_bind_peer(rt, 1);
                peer = rt->peer;
+               *release_it = false;
        }
 
-       if (peer) {
-               if ((s32)(peer->tcp_ts - tp->rx_opt.ts_recent) <= 0 ||
-                   ((u32)get_seconds() - peer->tcp_ts_stamp > TCP_PAWS_MSL &&
-                    peer->tcp_ts_stamp <= (u32)tp->rx_opt.ts_recent_stamp)) {
-                       peer->tcp_ts_stamp = (u32)tp->rx_opt.ts_recent_stamp;
-                       peer->tcp_ts = tp->rx_opt.ts_recent;
-               }
-               if (release_it)
-                       inet_putpeer(peer);
-               return 1;
-       }
-
-       return 0;
+       return peer;
 }
-EXPORT_SYMBOL(tcp_v4_remember_stamp);
+EXPORT_SYMBOL(tcp_v4_get_peer);
 
 int tcp_v4_tw_remember_stamp(struct inet_timewait_sock *tw)
 {
@@ -1828,7 +1809,7 @@ const struct inet_connection_sock_af_ops ipv4_specific = {
        .rebuild_header    = inet_sk_rebuild_header,
        .conn_request      = tcp_v4_conn_request,
        .syn_recv_sock     = tcp_v4_syn_recv_sock,
-       .remember_stamp    = tcp_v4_remember_stamp,
+       .get_peer          = tcp_v4_get_peer,
        .net_header_len    = sizeof(struct iphdr),
        .setsockopt        = ip_setsockopt,
        .getsockopt        = ip_getsockopt,
index 43cf901..059082c 100644 (file)
@@ -49,6 +49,35 @@ struct inet_timewait_death_row tcp_death_row = {
 };
 EXPORT_SYMBOL_GPL(tcp_death_row);
 
+/* VJ's idea. Save last timestamp seen from this destination
+ * and hold it at least for normal timewait interval to use for duplicate
+ * segment detection in subsequent connections, before they enter synchronized
+ * state.
+ */
+
+static int tcp_remember_stamp(struct sock *sk)
+{
+       const struct inet_connection_sock *icsk = inet_csk(sk);
+       struct tcp_sock *tp = tcp_sk(sk);
+       struct inet_peer *peer;
+       bool release_it;
+
+       peer = icsk->icsk_af_ops->get_peer(sk, &release_it);
+       if (peer) {
+               if ((s32)(peer->tcp_ts - tp->rx_opt.ts_recent) <= 0 ||
+                   ((u32)get_seconds() - peer->tcp_ts_stamp > TCP_PAWS_MSL &&
+                    peer->tcp_ts_stamp <= (u32)tp->rx_opt.ts_recent_stamp)) {
+                       peer->tcp_ts_stamp = (u32)tp->rx_opt.ts_recent_stamp;
+                       peer->tcp_ts = tp->rx_opt.ts_recent;
+               }
+               if (release_it)
+                       inet_putpeer(peer);
+               return 1;
+       }
+
+       return 0;
+}
+
 static __inline__ int tcp_in_window(u32 seq, u32 end_seq, u32 s_win, u32 e_win)
 {
        if (seq == s_win)
@@ -274,7 +303,7 @@ void tcp_time_wait(struct sock *sk, int state, int timeo)
        int recycle_ok = 0;
 
        if (tcp_death_row.sysctl_tw_recycle && tp->rx_opt.ts_recent_stamp)
-               recycle_ok = icsk->icsk_af_ops->remember_stamp(sk);
+               recycle_ok = tcp_remember_stamp(sk);
 
        if (tcp_death_row.tw_count < tcp_death_row.sysctl_max_tw_buckets)
                tw = inet_twsk_alloc(sk, state);
index 7e41e2c..e394d00 100644 (file)
@@ -1818,10 +1818,10 @@ do_time_wait:
        goto discard_it;
 }
 
-static int tcp_v6_remember_stamp(struct sock *sk)
+struct inet_peer *tcp_v6_get_peer(struct sock *sk, bool *release_it)
 {
        /* Alas, not yet... */
-       return 0;
+       return NULL;
 }
 
 static const struct inet_connection_sock_af_ops ipv6_specific = {
@@ -1830,7 +1830,7 @@ static const struct inet_connection_sock_af_ops ipv6_specific = {
        .rebuild_header    = inet6_sk_rebuild_header,
        .conn_request      = tcp_v6_conn_request,
        .syn_recv_sock     = tcp_v6_syn_recv_sock,
-       .remember_stamp    = tcp_v6_remember_stamp,
+       .get_peer          = tcp_v6_get_peer,
        .net_header_len    = sizeof(struct ipv6hdr),
        .setsockopt        = ipv6_setsockopt,
        .getsockopt        = ipv6_getsockopt,
@@ -1862,7 +1862,7 @@ static const struct inet_connection_sock_af_ops ipv6_mapped = {
        .rebuild_header    = inet_sk_rebuild_header,
        .conn_request      = tcp_v6_conn_request,
        .syn_recv_sock     = tcp_v6_syn_recv_sock,
-       .remember_stamp    = tcp_v4_remember_stamp,
+       .get_peer          = tcp_v4_get_peer,
        .net_header_len    = sizeof(struct iphdr),
        .setsockopt        = ipv6_setsockopt,
        .getsockopt        = ipv6_getsockopt,