From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: [PATCH net-next2.6] ipv6: avoid dev_hold()/dev_put() in rawv6_bind() Date: Fri, 06 Nov 2009 11:53:22 +0100 Message-ID: <4AF40022.6050100@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: Linux Netdev List To: "David S. Miller" Return-path: Received: from gw1.cosmosbay.com ([212.99.114.194]:40097 "EHLO gw1.cosmosbay.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756413AbZKFKxU (ORCPT ); Fri, 6 Nov 2009 05:53:20 -0500 Sender: netdev-owner@vger.kernel.org List-ID: Using RCU helps not touching device refcount in rawv6_bind() Signed-off-by: Eric Dumazet --- net/ipv6/raw.c | 23 +++++++++++------------ 1 files changed, 11 insertions(+), 12 deletions(-) diff --git a/net/ipv6/raw.c b/net/ipv6/raw.c index 818ef21..80f356a 100644 --- a/net/ipv6/raw.c +++ b/net/ipv6/raw.c @@ -249,7 +249,7 @@ static int rawv6_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len) /* Raw sockets are IPv6 only */ if (addr_type == IPV6_ADDR_MAPPED) - return(-EADDRNOTAVAIL); + return -EADDRNOTAVAIL; lock_sock(sk); @@ -257,6 +257,7 @@ static int rawv6_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len) if (sk->sk_state != TCP_CLOSE) goto out; + rcu_read_unlock(); /* Check if the address belongs to the host. */ if (addr_type != IPV6_ADDR_ANY) { struct net_device *dev = NULL; @@ -272,13 +273,13 @@ static int rawv6_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len) /* Binding to link-local address requires an interface */ if (!sk->sk_bound_dev_if) - goto out; + goto out_unlock; - dev = dev_get_by_index(sock_net(sk), sk->sk_bound_dev_if); - if (!dev) { - err = -ENODEV; - goto out; - } + err = -ENODEV; + dev = dev_get_by_index_rcu(sock_net(sk), + sk->sk_bound_dev_if); + if (!dev) + goto out_unlock; } /* ipv4 addr of the socket is invalid. Only the @@ -289,13 +290,9 @@ static int rawv6_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len) err = -EADDRNOTAVAIL; if (!ipv6_chk_addr(sock_net(sk), &addr->sin6_addr, dev, 0)) { - if (dev) - dev_put(dev); - goto out; + goto out_unlock; } } - if (dev) - dev_put(dev); } inet->inet_rcv_saddr = inet->inet_saddr = v4addr; @@ -303,6 +300,8 @@ static int rawv6_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len) if (!(addr_type & IPV6_ADDR_MULTICAST)) ipv6_addr_copy(&np->saddr, &addr->sin6_addr); err = 0; +out_unlock: + rcu_read_unlock(); out: release_sock(sk); return err;