[TWSK]: Introduce struct timewait_sock_ops

So that we can share several timewait sockets related functions and
make the timewait mini sockets infrastructure closer to the request
mini sockets one.

Next changesets will take advantage of this, moving more code out of
TCP and DCCP v4 and v6 to common infrastructure.

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

5 files changed, 40 insertions, 4 deletions

diff --git a/include/linux/ipv6.h b/include/linux/ipv6.h
index 7d3908594fac..a0d04891fe12 100644
--- a/include/linux/ipv6.h
+++ b/include/linux/ipv6.h
@@ -360,7 +360,8 @@ struct tcp6_timewait_sock {
 
 static inline u16 inet6_tw_offset(const struct proto *prot)
 {
-        return prot->twsk_obj_size - sizeof(struct inet6_timewait_sock);
+        return prot->twsk_prot->twsk_obj_size -
+                        sizeof(struct inet6_timewait_sock);
 }
 
 static inline struct inet6_timewait_sock *inet6_twsk(const struct sock *sk)
diff --git a/include/net/inet_timewait_sock.h b/include/net/inet_timewait_sock.h
index ca240f856c46..e396a65473d7 100644
--- a/include/net/inet_timewait_sock.h
+++ b/include/net/inet_timewait_sock.h
@@ -26,6 +26,7 @@
 
 #include <net/sock.h>
 #include <net/tcp_states.h>
+#include <net/timewait_sock.h>
 
 #include <asm/atomic.h>
 
@@ -200,7 +201,7 @@ static inline void inet_twsk_put(struct inet_timewait_sock *tw)
                 printk(KERN_DEBUG "%s timewait_sock %p released\n",
                        tw->tw_prot->name, tw);
 #endif
-                kmem_cache_free(tw->tw_prot->twsk_slab, tw);
+                kmem_cache_free(tw->tw_prot->twsk_prot->twsk_slab, tw);
                 module_put(owner);
         }
 }
diff --git a/include/net/sock.h b/include/net/sock.h
index 0fbae85c6d55..91d28957dc10 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -493,6 +493,7 @@ extern void sk_stream_kill_queues(struct sock *sk);
 extern int sk_wait_data(struct sock *sk, long *timeo);
 
 struct request_sock_ops;
+struct timewait_sock_ops;
 
 /* Networking protocol blocks we attach to sockets.
  * socket layer -> transport layer interface
@@ -557,11 +558,10 @@ struct proto {
         kmem_cache_t            *slab;
         unsigned int            obj_size;
 
-        kmem_cache_t            *twsk_slab;
-        unsigned int            twsk_obj_size;
         atomic_t                *orphan_count;
 
         struct request_sock_ops *rsk_prot;
+        struct timewait_sock_ops *twsk_prot;
 
         struct module           *owner;
 
diff --git a/include/net/tcp.h b/include/net/tcp.h
index 83b117a25c2a..176221cd0cce 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -287,6 +287,9 @@ extern int			tcp_rcv_established(struct sock *sk,
 
 extern void                     tcp_rcv_space_adjust(struct sock *sk);
 
+extern int                      tcp_twsk_unique(struct sock *sk,
+                                                struct sock *sktw, void *twp);
+
 static inline void tcp_dec_quickack_mode(struct sock *sk,
                                          const unsigned int pkts)
 {
diff --git a/include/net/timewait_sock.h b/include/net/timewait_sock.h
new file mode 100644
index 000000000000..2544281e1d5e
--- /dev/null
+++ b/include/net/timewait_sock.h
@@ -0,0 +1,31 @@
+/*
+ * NET          Generic infrastructure for Network protocols.
+ *
+ * Authors:     Arnaldo Carvalho de Melo <acme@conectiva.com.br>
+ *
+ *              This program is free software; you can redistribute it and/or
+ *              modify it under the terms of the GNU General Public License
+ *              as published by the Free Software Foundation; either version
+ *              2 of the License, or (at your option) any later version.
+ */
+#ifndef _TIMEWAIT_SOCK_H
+#define _TIMEWAIT_SOCK_H
+
+#include <linux/slab.h>
+#include <net/sock.h>
+
+struct timewait_sock_ops {
+        kmem_cache_t    *twsk_slab;
+        unsigned int    twsk_obj_size;
+        int             (*twsk_unique)(struct sock *sk,
+                                       struct sock *sktw, void *twp);
+};
+
+static inline int twsk_unique(struct sock *sk, struct sock *sktw, void *twp)
+{
+        if (sk->sk_prot->twsk_prot->twsk_unique != NULL)
+                return sk->sk_prot->twsk_prot->twsk_unique(sk, sktw, twp);
+        return 0;
+}
+
+#endif /* _TIMEWAIT_SOCK_H */