[PATCH 4.9 56/71] net: refactor bind_bucket fastreuse into helper

[Greg Kroah-Hartman]

From: Tim Froidcoeur <tim.froidco...@tessares.net>

commit 62ffc589abb176821662efc4525ee4ac0b9c3894 upstream.

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.bae...@tessares.net>
Signed-off-by: Tim Froidcoeur <tim.froidco...@tessares.net>
Signed-off-by: David S. Miller <da...@davemloft.net>
Signed-off-by: Tim Froidcoeur <tim.froidco...@tessares.net>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
 include/net/inet_connection_sock.h |    4 ++++
 net/ipv4/inet_connection_sock.c    |   37 +++++++++++++++++++++++++------------
 2 files changed, 29 insertions(+), 12 deletions(-)

--- a/include/net/inet_connection_sock.h
+++ b/include/net/inet_connection_sock.h
@@ -319,5 +319,9 @@ int inet_csk_compat_getsockopt(struct so
 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 */
--- a/net/ipv4/inet_connection_sock.c
+++ b/net/ipv4/inet_connection_sock.c
@@ -89,6 +89,28 @@ int inet_csk_bind_conflict(const struct
 }
 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);
+       bool reuse = sk->sk_reuse && sk->sk_state != TCP_LISTEN;
+
+       if (!hlist_empty(&tb->owners)) {
+               if (!reuse)
+                       tb->fastreuse = 0;
+               if (!sk->sk_reuseport || !uid_eq(tb->fastuid, uid))
+                       tb->fastreuseport = 0;
+       } else {
+               tb->fastreuse = reuse;
+               if (sk->sk_reuseport) {
+                       tb->fastreuseport = 1;
+                       tb->fastuid = uid;
+               } else {
+                       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.
  * We try to allocate an odd port (and leave even ports for connect())
@@ -218,19 +240,10 @@ tb_found:
                        }
                        goto fail_unlock;
                }
-               if (!reuse)
-                       tb->fastreuse = 0;
-               if (!sk->sk_reuseport || !uid_eq(tb->fastuid, uid))
-                       tb->fastreuseport = 0;
-       } else {
-               tb->fastreuse = reuse;
-               if (sk->sk_reuseport) {
-                       tb->fastreuseport = 1;
-                       tb->fastuid = uid;
-               } else {
-                       tb->fastreuseport = 0;
-               }
        }
+
+       inet_csk_update_fastreuse(tb, sk);
+
 success:
        if (!inet_csk(sk)->icsk_bind_hash)
                inet_bind_hash(sk, tb, port);