[INET_TWSK]: Introduce inet_twsk_alloc

With the parts of tcp_time_wait that are not TCP specific, tcp_time_wait uses
it and so will dccp_time_wait.

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

3 files changed, 33 insertions, 22 deletions

diff --git a/include/net/inet_timewait_sock.h b/include/net/inet_timewait_sock.h
index 020f28058fd4..e00861b16696 100644
--- a/include/net/inet_timewait_sock.h
+++ b/include/net/inet_timewait_sock.h
@@ -142,6 +142,9 @@ static inline void inet_twsk_put(struct inet_timewait_sock *tw)
         }
 }
 
+extern struct inet_timewait_sock *inet_twsk_alloc(const struct sock *sk,
+                                                  const int state);
+
 extern void __inet_twsk_kill(struct inet_timewait_sock *tw,
                              struct inet_hashinfo *hashinfo);
 
diff --git a/net/ipv4/inet_timewait_sock.c b/net/ipv4/inet_timewait_sock.c
index d38d160faeb7..ceb577c74237 100644
--- a/net/ipv4/inet_timewait_sock.c
+++ b/net/ipv4/inet_timewait_sock.c
@@ -81,3 +81,31 @@ void __inet_twsk_hashdance(struct inet_timewait_sock *tw, struct sock *sk,
 
         write_unlock(&ehead->lock);
 }
+
+struct inet_timewait_sock *inet_twsk_alloc(const struct sock *sk, const int state)
+{
+        struct inet_timewait_sock *tw = kmem_cache_alloc(sk->sk_prot_creator->twsk_slab,
+                                                         SLAB_ATOMIC);
+        if (tw != NULL) {
+                const struct inet_sock *inet = inet_sk(sk);
+
+                /* Give us an identity. */
+                tw->tw_daddr        = inet->daddr;
+                tw->tw_rcv_saddr    = inet->rcv_saddr;
+                tw->tw_bound_dev_if = sk->sk_bound_dev_if;
+                tw->tw_num          = inet->num;
+                tw->tw_state        = TCP_TIME_WAIT;
+                tw->tw_substate     = state;
+                tw->tw_sport        = inet->sport;
+                tw->tw_dport        = inet->dport;
+                tw->tw_family       = sk->sk_family;
+                tw->tw_reuse        = sk->sk_reuse;
+                tw->tw_hashent      = sk->sk_hashent;
+                tw->tw_ipv6only     = 0;
+                tw->tw_prot         = sk->sk_prot_creator;
+                atomic_set(&tw->tw_refcnt, 1);
+                inet_twsk_dead_node_init(tw);
+        }
+
+        return tw;
+}
diff --git a/net/ipv4/tcp_minisocks.c b/net/ipv4/tcp_minisocks.c
index 4112f7a6d108..66ce1790a94f 100644
--- a/net/ipv4/tcp_minisocks.c
+++ b/net/ipv4/tcp_minisocks.c
@@ -267,37 +267,18 @@ void tcp_time_wait(struct sock *sk, int state, int timeo)
                 recycle_ok = tp->af_specific->remember_stamp(sk);
 
         if (tcp_tw_count < sysctl_tcp_max_tw_buckets)
-                tw = kmem_cache_alloc(sk->sk_prot_creator->twsk_slab, SLAB_ATOMIC);
+                tw = inet_twsk_alloc(sk, state);
 
         if (tw != NULL) {
                 struct tcp_timewait_sock *tcptw = tcp_twsk((struct sock *)tw);
-                const struct inet_sock *inet = inet_sk(sk);
                 const int rto = (tp->rto << 2) - (tp->rto >> 1);
 
-                /* Remember our protocol */
-                tw->tw_prot             = sk->sk_prot_creator;
-
-                /* Give us an identity. */
-                tw->tw_daddr            = inet->daddr;
-                tw->tw_rcv_saddr        = inet->rcv_saddr;
-                tw->tw_bound_dev_if     = sk->sk_bound_dev_if;
-                tw->tw_num              = inet->num;
-                tw->tw_state            = TCP_TIME_WAIT;
-                tw->tw_substate         = state;
-                tw->tw_sport            = inet->sport;
-                tw->tw_dport            = inet->dport;
-                tw->tw_family           = sk->sk_family;
-                tw->tw_reuse            = sk->sk_reuse;
                 tw->tw_rcv_wscale       = tp->rx_opt.rcv_wscale;
-                atomic_set(&tw->tw_refcnt, 1);
-
-                tw->tw_hashent          = sk->sk_hashent;
                 tcptw->tw_rcv_nxt       = tp->rcv_nxt;
                 tcptw->tw_snd_nxt       = tp->snd_nxt;
                 tcptw->tw_rcv_wnd       = tcp_receive_window(tp);
                 tcptw->tw_ts_recent     = tp->rx_opt.ts_recent;
                 tcptw->tw_ts_recent_stamp = tp->rx_opt.ts_recent_stamp;
-                inet_twsk_dead_node_init(tw);
 
 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
                 if (tw->tw_family == PF_INET6) {
@@ -307,8 +288,7 @@ void tcp_time_wait(struct sock *sk, int state, int timeo)
                         ipv6_addr_copy(&tcp6tw->tw_v6_daddr, &np->daddr);
                         ipv6_addr_copy(&tcp6tw->tw_v6_rcv_saddr, &np->rcv_saddr);
                         tw->tw_ipv6only = np->ipv6only;
-                } else
-                        tw->tw_ipv6only = 0;
+                }
 #endif
                 /* Linkage updates. */
                 __inet_twsk_hashdance(tw, sk, &tcp_hashinfo);