[NET] NETNS: Omit net_device->nd_net without CONFIG_NET_NS.

Introduce per-net_device inlines: dev_net(), dev_net_set().
Without CONFIG_NET_NS, no namespace other than &init_net exists.
Let's explicitly define them to help compiler optimizations.

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>

2 files changed, 27 insertions, 4 deletions

diff --git a/include/linux/inetdevice.h b/include/linux/inetdevice.h
index da05ab47ff2f..7009b0cdd06f 100644
--- a/include/linux/inetdevice.h
+++ b/include/linux/inetdevice.h
@@ -70,13 +70,13 @@ static inline void ipv4_devconf_setall(struct in_device *in_dev)
 	ipv4_devconf_set((in_dev), NET_IPV4_CONF_ ## attr, (val))
 
 #define IN_DEV_ANDCONF(in_dev, attr) \
-	(IPV4_DEVCONF_ALL(in_dev->dev->nd_net, attr) && \
+	(IPV4_DEVCONF_ALL(dev_net(in_dev->dev), attr) && \
 	 IN_DEV_CONF_GET((in_dev), attr))
 #define IN_DEV_ORCONF(in_dev, attr) \
-	(IPV4_DEVCONF_ALL(in_dev->dev->nd_net, attr) || \
+	(IPV4_DEVCONF_ALL(dev_net(in_dev->dev), attr) || \
 	 IN_DEV_CONF_GET((in_dev), attr))
 #define IN_DEV_MAXCONF(in_dev, attr) \
-	(max(IPV4_DEVCONF_ALL(in_dev->dev->nd_net, attr), \
+	(max(IPV4_DEVCONF_ALL(dev_net(in_dev->dev), attr), \
 	     IN_DEV_CONF_GET((in_dev), attr)))
 
 #define IN_DEV_FORWARD(in_dev)		IN_DEV_CONF_GET((in_dev), FORWARDING)
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index ced61f87660e..d146be40f46c 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -708,8 +708,10 @@ struct net_device
 	void                    (*poll_controller)(struct net_device *dev);
 #endif
 
+#ifdef CONFIG_NET_NS
 	/* Network namespace this network device is inside */
 	struct net		*nd_net;
+#endif
 
 	/* bridge stuff */
 	struct net_bridge_port	*br_port;
@@ -737,6 +739,27 @@ struct net_device
 #define	NETDEV_ALIGN		32
 #define	NETDEV_ALIGN_CONST	(NETDEV_ALIGN - 1)
 
+/*
+ * Net namespace inlines
+ */
+static inline
+struct net *dev_net(const struct net_device *dev)
+{
+#ifdef CONFIG_NET_NS
+	return dev->nd_net;
+#else
+	return &init_net;
+#endif
+}
+
+static inline
+void dev_net_set(struct net_device *dev, const struct net *net)
+{
+#ifdef CONFIG_NET_NS
+	dev->nd_dev = net;
+#endif
+}
+
 /**
  *	netdev_priv - access network device private data
  *	@dev: network device
@@ -813,7 +836,7 @@ static inline struct net_device *next_net_device(struct net_device *dev)
 	struct list_head *lh;
 	struct net *net;
 
-	net = dev->nd_net;
+	net = dev_net(dev);
 	lh = dev->dev_list.next;
 	return lh == &net->dev_base_head ? NULL : net_device_entry(lh);
 }