[PATCH 4.4 1/2] net: refactor bind_bucket fastreuse into helper

[Tim Froidcoeur]

[ Upstream commit 62ffc589abb176821662efc4525ee4ac0b9c3894 ]

Refactor the fastreuse update code in inet_csk_get_port into a small
helper function that can be called from other places.

Acked-by: Matthieu Baerts <matthieu.baerts@xxxxxxxxxxxx>
Signed-off-by: Tim Froidcoeur <tim.froidcoeur@xxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Tim Froidcoeur <tim.froidcoeur@xxxxxxxxxxxx>
---
 include/net/inet_connection_sock.h |  4 +++
 net/ipv4/inet_connection_sock.c    | 46 ++++++++++++++++++------------
 2 files changed, 32 insertions(+), 18 deletions(-)

diff --git a/include/net/inet_connection_sock.h b/include/net/inet_connection_sock.h
index 72599bbc8255..a77a37c6349d 100644
--- a/include/net/inet_connection_sock.h
+++ b/include/net/inet_connection_sock.h
@@ -319,5 +319,9 @@ int inet_csk_compat_getsockopt(struct sock *sk, int level, int optname,
 int inet_csk_compat_setsockopt(struct sock *sk, int level, int optname,
 			       char __user *optval, unsigned int optlen);
 
+/* update the fast reuse flag when adding a socket */
+void inet_csk_update_fastreuse(struct inet_bind_bucket *tb,
+			       struct sock *sk);
+
 struct dst_entry *inet_csk_update_pmtu(struct sock *sk, u32 mtu);
 #endif /* _INET_CONNECTION_SOCK_H */
diff --git a/net/ipv4/inet_connection_sock.c b/net/ipv4/inet_connection_sock.c
index 6c9158805b57..9678dd8d70c3 100644
--- a/net/ipv4/inet_connection_sock.c
+++ b/net/ipv4/inet_connection_sock.c
@@ -87,6 +87,31 @@ int inet_csk_bind_conflict(const struct sock *sk,
 }
 EXPORT_SYMBOL_GPL(inet_csk_bind_conflict);
 
+void inet_csk_update_fastreuse(struct inet_bind_bucket *tb,
+			       struct sock *sk)
+{
+	kuid_t uid = sock_i_uid(sk);
+
+	if (hlist_empty(&tb->owners)) {
+		if (sk->sk_reuse && sk->sk_state != TCP_LISTEN)
+			tb->fastreuse = 1;
+		else
+			tb->fastreuse = 0;
+		if (sk->sk_reuseport) {
+			tb->fastreuseport = 1;
+			tb->fastuid = uid;
+		} else
+			tb->fastreuseport = 0;
+	} else {
+		if (tb->fastreuse &&
+		    (!sk->sk_reuse || sk->sk_state == TCP_LISTEN))
+			tb->fastreuse = 0;
+		if (tb->fastreuseport &&
+		    (!sk->sk_reuseport || !uid_eq(tb->fastuid, uid)))
+			tb->fastreuseport = 0;
+	}
+}
+
 /* Obtain a reference to a local port for the given sock,
  * if snum is zero it means select any available local port.
  */
@@ -216,24 +241,9 @@ tb_not_found:
 	if (!tb && (tb = inet_bind_bucket_create(hashinfo->bind_bucket_cachep,
 					net, head, snum)) == NULL)
 		goto fail_unlock;
-	if (hlist_empty(&tb->owners)) {
-		if (sk->sk_reuse && sk->sk_state != TCP_LISTEN)
-			tb->fastreuse = 1;
-		else
-			tb->fastreuse = 0;
-		if (sk->sk_reuseport) {
-			tb->fastreuseport = 1;
-			tb->fastuid = uid;
-		} else
-			tb->fastreuseport = 0;
-	} else {
-		if (tb->fastreuse &&
-		    (!sk->sk_reuse || sk->sk_state == TCP_LISTEN))
-			tb->fastreuse = 0;
-		if (tb->fastreuseport &&
-		    (!sk->sk_reuseport || !uid_eq(tb->fastuid, uid)))
-			tb->fastreuseport = 0;
-	}
+
+	inet_csk_update_fastreuse(tb, sk);
+
 success:
 	if (!inet_csk(sk)->icsk_bind_hash)
 		inet_bind_hash(sk, tb, snum);
-- 
2.25.1