ipv4: introduce __ip_dev_find()

ip_dev_find(net, addr) finds a device given an IPv4 source address and
takes a reference on it.

Introduce __ip_dev_find(), taking a third argument, to optionally take
the device reference. Callers not asking the reference to be taken
should be in an rcu_read_lock() protected section.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 6 insertions, 1 deletions

diff --git a/include/linux/inetdevice.h b/include/linux/inetdevice.h
index 1ec09bb4a3ab..ccd5b07d678d 100644
--- a/include/linux/inetdevice.h
+++ b/include/linux/inetdevice.h
@@ -159,7 +159,12 @@ struct in_ifaddr {
 extern int register_inetaddr_notifier(struct notifier_block *nb);
 extern int unregister_inetaddr_notifier(struct notifier_block *nb);
 
-extern struct net_device *ip_dev_find(struct net *net, __be32 addr);
+extern struct net_device *__ip_dev_find(struct net *net, __be32 addr, bool devref);
+static inline struct net_device *ip_dev_find(struct net *net, __be32 addr)
+{
+        return __ip_dev_find(net, addr, true);
+}
+
 extern int              inet_addr_onlink(struct in_device *in_dev, __be32 a, __be32 b);
 extern int              devinet_ioctl(struct net *net, unsigned int cmd, void __user *);
 extern void             devinet_init(void);