[INET]: Generalise tcp_v4_lookup_listener
[acme@toy net-2.6.14]$ grep built-in /tmp/before /tmp/after
/tmp/before: 282560 13122 9312 304994 4a762 net/ipv4/built-in.o
/tmp/after: 282560 13122 9312 304994 4a762 net/ipv4/built-in.o
Will be used in DCCP, not exporting it right now not to get in Adrian
Bunk's exported-but-not-used-on-modules radar 8)
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/inet_hashtables.h b/include/net/inet_hashtables.h
index 6731df2..1c4fa00 100644
--- a/include/net/inet_hashtables.h
+++ b/include/net/inet_hashtables.h
@@ -16,8 +16,10 @@
#include <linux/interrupt.h>
#include <linux/ip.h>
+#include <linux/ipv6.h>
#include <linux/list.h>
#include <linux/slab.h>
+#include <linux/socket.h>
#include <linux/spinlock.h>
#include <linux/types.h>
#include <linux/wait.h>
@@ -274,4 +276,38 @@
if (sk->sk_state == TCP_LISTEN)
wake_up(&hashinfo->lhash_wait);
}
+
+extern struct sock *__inet_lookup_listener(const struct hlist_head *head,
+ const u32 daddr,
+ const unsigned short hnum,
+ const int dif);
+
+/* Optimize the common listener case. */
+static inline struct sock *inet_lookup_listener(struct inet_hashinfo *hashinfo,
+ const u32 daddr,
+ const unsigned short hnum,
+ const int dif)
+{
+ struct sock *sk = NULL;
+ struct hlist_head *head;
+
+ read_lock(&hashinfo->lhash_lock);
+ head = &hashinfo->listening_hash[inet_lhashfn(hnum)];
+ if (!hlist_empty(head)) {
+ const struct inet_sock *inet = inet_sk((sk = __sk_head(head)));
+
+ if (inet->num == hnum && !sk->sk_node.next &&
+ (!inet->rcv_saddr || inet->rcv_saddr == daddr) &&
+ (sk->sk_family == PF_INET || !ipv6_only_sock(sk)) &&
+ !sk->sk_bound_dev_if)
+ goto sherry_cache;
+ sk = __inet_lookup_listener(head, daddr, hnum, dif);
+ }
+ if (sk) {
+sherry_cache:
+ sock_hold(sk);
+ }
+ read_unlock(&hashinfo->lhash_lock);
+ return sk;
+}
#endif /* _INET_HASHTABLES_H */
diff --git a/net/ipv4/inet_hashtables.c b/net/ipv4/inet_hashtables.c
index 06cbc6f..88fcba05b 100644
--- a/net/ipv4/inet_hashtables.c
+++ b/net/ipv4/inet_hashtables.c
@@ -121,3 +121,44 @@
}
EXPORT_SYMBOL(inet_listen_wlock);
+
+/*
+ * Don't inline this cruft. Here are some nice properties to exploit here. The
+ * BSD API does not allow a listening sock to specify the remote port nor the
+ * remote address for the connection. So always assume those are both
+ * wildcarded during the search since they can never be otherwise.
+ */
+struct sock *__inet_lookup_listener(const struct hlist_head *head, const u32 daddr,
+ const unsigned short hnum, const int dif)
+{
+ struct sock *result = NULL, *sk;
+ const struct hlist_node *node;
+ int hiscore = -1;
+
+ sk_for_each(sk, node, head) {
+ const struct inet_sock *inet = inet_sk(sk);
+
+ if (inet->num == hnum && !ipv6_only_sock(sk)) {
+ const __u32 rcv_saddr = inet->rcv_saddr;
+ int score = sk->sk_family == PF_INET ? 1 : 0;
+
+ if (rcv_saddr) {
+ if (rcv_saddr != daddr)
+ continue;
+ score += 2;
+ }
+ if (sk->sk_bound_dev_if) {
+ if (sk->sk_bound_dev_if != dif)
+ continue;
+ score += 2;
+ }
+ if (score == 5)
+ return sk;
+ if (score > hiscore) {
+ hiscore = score;
+ result = sk;
+ }
+ }
+ }
+ return result;
+}
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index dca1be6..a678709 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -238,78 +238,6 @@
inet_unhash(&tcp_hashinfo, sk);
}
-/* Don't inline this cruft. Here are some nice properties to
- * exploit here. The BSD API does not allow a listening TCP
- * to specify the remote port nor the remote address for the
- * connection. So always assume those are both wildcarded
- * during the search since they can never be otherwise.
- */
-static struct sock *__tcp_v4_lookup_listener(struct hlist_head *head,
- const u32 daddr,
- const unsigned short hnum,
- const int dif)
-{
- struct sock *result = NULL, *sk;
- struct hlist_node *node;
- int score, hiscore;
-
- hiscore=-1;
- sk_for_each(sk, node, head) {
- struct inet_sock *inet = inet_sk(sk);
-
- if (inet->num == hnum && !ipv6_only_sock(sk)) {
- __u32 rcv_saddr = inet->rcv_saddr;
-
- score = (sk->sk_family == PF_INET ? 1 : 0);
- if (rcv_saddr) {
- if (rcv_saddr != daddr)
- continue;
- score+=2;
- }
- if (sk->sk_bound_dev_if) {
- if (sk->sk_bound_dev_if != dif)
- continue;
- score+=2;
- }
- if (score == 5)
- return sk;
- if (score > hiscore) {
- hiscore = score;
- result = sk;
- }
- }
- }
- return result;
-}
-
-/* Optimize the common listener case. */
-static inline struct sock *tcp_v4_lookup_listener(const u32 daddr,
- const unsigned short hnum,
- const int dif)
-{
- struct sock *sk = NULL;
- struct hlist_head *head;
-
- read_lock(&tcp_hashinfo.lhash_lock);
- head = &tcp_hashinfo.listening_hash[inet_lhashfn(hnum)];
- if (!hlist_empty(head)) {
- struct inet_sock *inet = inet_sk((sk = __sk_head(head)));
-
- if (inet->num == hnum && !sk->sk_node.next &&
- (!inet->rcv_saddr || inet->rcv_saddr == daddr) &&
- (sk->sk_family == PF_INET || !ipv6_only_sock(sk)) &&
- !sk->sk_bound_dev_if)
- goto sherry_cache;
- sk = __tcp_v4_lookup_listener(head, daddr, hnum, dif);
- }
- if (sk) {
-sherry_cache:
- sock_hold(sk);
- }
- read_unlock(&tcp_hashinfo.lhash_lock);
- return sk;
-}
-
/* Sockets in TCP_CLOSE state are _always_ taken out of the hash, so
* we need not check it for TCP lookups anymore, thanks Alexey. -DaveM
*
@@ -358,7 +286,7 @@
struct sock *sk = __tcp_v4_lookup_established(saddr, sport,
daddr, hnum, dif);
- return sk ? : tcp_v4_lookup_listener(daddr, hnum, dif);
+ return sk ? : inet_lookup_listener(&tcp_hashinfo, daddr, hnum, dif);
}
inline struct sock *tcp_v4_lookup(u32 saddr, u16 sport, u32 daddr,
@@ -1641,9 +1569,10 @@
switch (tcp_timewait_state_process((struct tcp_tw_bucket *)sk,
skb, th, skb->len)) {
case TCP_TW_SYN: {
- struct sock *sk2 = tcp_v4_lookup_listener(skb->nh.iph->daddr,
- ntohs(th->dest),
- tcp_v4_iif(skb));
+ struct sock *sk2 = inet_lookup_listener(&tcp_hashinfo,
+ skb->nh.iph->daddr,
+ ntohs(th->dest),
+ tcp_v4_iif(skb));
if (sk2) {
tcp_tw_deschedule((struct tcp_tw_bucket *)sk);
tcp_tw_put((struct tcp_tw_bucket *)sk);