[PATCH 4.19 136/168] net: refactor bind_bucket fastreuse into helper

Greg Kroah-Hartman
2020-08-17T17:35:18Z

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

[ 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@tessares.net>
Signed-off-by: Tim Froidcoeur <tim.froidcoeur@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
include/net/inet_connection_sock.h | 4 +
net/ipv4/inet_connection_sock.c | 93 ++++++++++++++++++++-----------------
2 files changed, 55 insertions(+), 42 deletions(-)

--- a/include/net/inet_connection_sock.h
+++ b/include/net/inet_connection_sock.h
@@ -313,5 +313,9 @@ 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
@@ -285,51 +285,12 @@ static inline int sk_reuseport_match(str
ipv6_only_sock(sk), true, false);
}

-/* 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())
- */
-int inet_csk_get_port(struct sock *sk, unsigned short snum)
+void inet_csk_update_fastreuse(struct inet_bind_bucket *tb,
+ struct sock *sk)
{
- bool reuse = sk->sk_reuse && sk->sk_state != TCP_LISTEN;
- struct inet_hashinfo *hinfo = sk->sk_prot->h.hashinfo;
- int ret = 1, port = snum;
- struct inet_bind_hashbucket *head;
- struct net *net = sock_net(sk);
- struct inet_bind_bucket *tb = NULL;
kuid_t uid = sock_i_uid(sk);
+ bool reuse = sk->sk_reuse && sk->sk_state != TCP_LISTEN;

- if (!port) {
- head = inet_csk_find_open_port(sk, &tb, &port);
- if (!head)
- return ret;
- if (!tb)
- goto tb_not_found;
- goto success;
- }
- head = &hinfo->bhash[inet_bhashfn(net, port,
- hinfo->bhash_size)];
- spin_lock_bh(&head->lock);
- inet_bind_bucket_for_each(tb, &head->chain)
- if (net_eq(ib_net(tb), net) && tb->port == port)
- goto tb_found;
-tb_not_found:
- tb = inet_bind_bucket_create(hinfo->bind_bucket_cachep,
- net, head, port);
- if (!tb)
- goto fail_unlock;
-tb_found:
- if (!hlist_empty(&tb->owners)) {
- if (sk->sk_reuse == SK_FORCE_REUSE)
- goto success;
-
- if ((tb->fastreuse > 0 && reuse) ||
- sk_reuseport_match(tb, sk))
- goto success;
- if (inet_csk_bind_conflict(sk, tb, true, true))
- goto fail_unlock;
- }
-success:
if (hlist_empty(&tb->owners)) {
tb->fastreuse = reuse;
if (sk->sk_reuseport) {
@@ -373,6 +334,54 @@ success:
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())
+ */
+int inet_csk_get_port(struct sock *sk, unsigned short snum)
+{
+ bool reuse = sk->sk_reuse && sk->sk_state != TCP_LISTEN;
+ struct inet_hashinfo *hinfo = sk->sk_prot->h.hashinfo;
+ int ret = 1, port = snum;
+ struct inet_bind_hashbucket *head;
+ struct net *net = sock_net(sk);
+ struct inet_bind_bucket *tb = NULL;
+
+ if (!port) {
+ head = inet_csk_find_open_port(sk, &tb, &port);
+ if (!head)
+ return ret;
+ if (!tb)
+ goto tb_not_found;
+ goto success;
+ }
+ head = &hinfo->bhash[inet_bhashfn(net, port,
+ hinfo->bhash_size)];
+ spin_lock_bh(&head->lock);
+ inet_bind_bucket_for_each(tb, &head->chain)
+ if (net_eq(ib_net(tb), net) && tb->port == port)
+ goto tb_found;
+tb_not_found:
+ tb = inet_bind_bucket_create(hinfo->bind_bucket_cachep,
+ net, head, port);
+ if (!tb)
+ goto fail_unlock;
+tb_found:
+ if (!hlist_empty(&tb->owners)) {
+ if (sk->sk_reuse == SK_FORCE_REUSE)
+ goto success;
+
+ if ((tb->fastreuse > 0 && reuse) ||
+ sk_reuseport_match(tb, sk))
+ goto success;
+ if (inet_csk_bind_conflict(sk, tb, true, true))
+ goto fail_unlock;
+ }
+success:
+ inet_csk_update_fastreuse(tb, sk);
+
if (!inet_csk(sk)->icsk_bind_hash)
inet_bind_hash(sk, tb, port);
WARN_ON(inet_csk(sk)->icsk_bind_hash != tb);