[PATCH net-next RFC v1 07/27] ipv4: introduce ifa_find_rcu

[Hannes Frederic Sowa]

Signed-off-by: Hannes Frederic Sowa <han...@stressinduktion.org>
---
 include/linux/inetdevice.h |  1 +
 net/ipv4/devinet.c         | 29 +++++++++++++++++------------
 2 files changed, 18 insertions(+), 12 deletions(-)

diff --git a/include/linux/inetdevice.h b/include/linux/inetdevice.h
index d5ac959e90baa1..eb1b662f62626f 100644
--- a/include/linux/inetdevice.h
+++ b/include/linux/inetdevice.h
@@ -159,6 +159,7 @@ int unregister_inetaddr_notifier(struct notifier_block *nb);
 void inet_netconf_notify_devconf(struct net *net, int type, int ifindex,
                                 struct ipv4_devconf *devconf);
 
+struct in_ifaddr *ifa_find_rcu(struct net *net, __be32 addr);
 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)
 {
diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c
index d4a38b6e9adb79..cc15afefa1df0a 100644
--- a/net/ipv4/devinet.c
+++ b/net/ipv4/devinet.c
@@ -128,6 +128,20 @@ static void inet_hash_remove(struct in_ifaddr *ifa)
        hlist_del_init_rcu(&ifa->hash);
 }
 
+struct in_ifaddr *ifa_find_rcu(struct net *net, __be32 addr)
+{
+       u32 hash = inet_addr_hash(net, addr);
+       struct in_ifaddr *ifa;
+
+       hlist_for_each_entry_rcu(ifa, &inet_addr_lst[hash], hash) {
+               if (ifa->ifa_local == addr &&
+                   net_eq(dev_net(ifa->ifa_dev->dev), net))
+                       return ifa;
+       }
+
+       return NULL;
+}
+
 /**
  * __ip_dev_find - find the first device with a given source address.
  * @net: the net namespace
@@ -138,21 +152,12 @@ static void inet_hash_remove(struct in_ifaddr *ifa)
  */
 struct net_device *__ip_dev_find(struct net *net, __be32 addr, bool devref)
 {
-       u32 hash = inet_addr_hash(net, addr);
-       struct net_device *result = NULL;
+       struct net_device *result;
        struct in_ifaddr *ifa;
 
        rcu_read_lock();
-       hlist_for_each_entry_rcu(ifa, &inet_addr_lst[hash], hash) {
-               if (ifa->ifa_local == addr) {
-                       struct net_device *dev = ifa->ifa_dev->dev;
-
-                       if (!net_eq(dev_net(dev), net))
-                               continue;
-                       result = dev;
-                       break;
-               }
-       }
+       ifa = ifa_find_rcu(net, addr);
+       result = ifa ? ifa->ifa_dev->dev : NULL;
        if (!result) {
                struct flowi4 fl4 = { .daddr = addr };
                struct fib_result res = { 0 };
-- 
2.9.3