[IPV4]: Unify and cleanup calls to devinet_sysctl_register

Currently this call is used to register sysctls for devices
and for the "default" confs. The "all" sysctls are registered
separately.

Besides, the inet_device is passed to this function, but it is
not needed there at all - just the device name and ifindex are
required.

Thanks to Herbert, who noticed, that this call doesn't even
require the devconf pointer (the last argument) - all we need
we can take from the in_device itself.

The fix is to make a __devinet_sysctl_register(), which registers
sysctls for all "devices" we need, including "default" and "all" :)

The original devinet_sysctl_register() works with struct net_device,
not the inet_device, and calls the introduced function, passing
the device name and ifindex (to be used as procname and ctl_name)
into it.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv4/devinet.c

@@ -98,8 +98,7 @@ static BLOCKING_NOTIFIER_HEAD(inetaddr_chain);
 static void inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap,
 			 int destroy);
 #ifdef CONFIG_SYSCTL
-static void devinet_sysctl_register(struct in_device *in_dev,
-				    struct ipv4_devconf *p);
+static void devinet_sysctl_register(struct in_device *idev);
 static void devinet_sysctl_unregister(struct ipv4_devconf *p);
 #endif
 
@@ -173,7 +172,7 @@ static struct in_device *inetdev_init(struct net_device *dev)
 	in_dev_hold(in_dev);
 
 #ifdef CONFIG_SYSCTL
-	devinet_sysctl_register(in_dev, &in_dev->cnf);
+	devinet_sysctl_register(in_dev);
 #endif
 	ip_mc_init_dev(in_dev);
 	if (dev->flags & IFF_UP)
@@ -1119,7 +1118,7 @@ static int inetdev_event(struct notifier_block *this, unsigned long event,
 		neigh_sysctl_unregister(in_dev->arp_parms);
 		neigh_sysctl_register(dev, in_dev->arp_parms, NET_IPV4,
 				      NET_IPV4_NEIGH, "ipv4", NULL, NULL);
-		devinet_sysctl_register(in_dev, &in_dev->cnf);
+		devinet_sysctl_register(in_dev);
 #endif
 		break;
 	}
@@ -1501,13 +1500,11 @@ static struct devinet_sysctl_table {
 	},
 };
 
-static void devinet_sysctl_register(struct in_device *in_dev,
-				    struct ipv4_devconf *p)
+static void __devinet_sysctl_register(char *dev_name, int ctl_name,
+		struct ipv4_devconf *p)
 {
 	int i;
-	struct net_device *dev = in_dev ? in_dev->dev : NULL;
 	struct devinet_sysctl_table *t;
-	char *dev_name = NULL;
 
 	t = kmemdup(&devinet_sysctl, sizeof(*t), GFP_KERNEL);
 	if (!t)
@@ -1518,13 +1515,7 @@ static void devinet_sysctl_register(struct in_device *in_dev,
 		t->devinet_vars[i].extra1 = p;
 	}
 
-	if (dev) {
-		dev_name = dev->name;
-		t->devinet_dev[0].ctl_name = dev->ifindex;
-	} else {
-		dev_name = "default";
-		t->devinet_dev[0].ctl_name = NET_PROTO_CONF_DEFAULT;
-	}
+	t->devinet_dev[0].ctl_name = ctl_name;
 
 	/*
 	 * Make a copy of dev_name, because '.procname' is regarded as const
@@ -1556,6 +1547,12 @@ static void devinet_sysctl_register(struct in_device *in_dev,
 	return;
 }
 
+static void devinet_sysctl_register(struct in_device *idev)
+{
+	return __devinet_sysctl_register(idev->dev->name, idev->dev->ifindex,
+			&idev->cnf);
+}
+
 static void devinet_sysctl_unregister(struct ipv4_devconf *p)
 {
 	if (p->sysctl) {
@@ -1577,9 +1574,10 @@ void __init devinet_init(void)
 	rtnl_register(PF_INET, RTM_DELADDR, inet_rtm_deladdr, NULL);
 	rtnl_register(PF_INET, RTM_GETADDR, NULL, inet_dump_ifaddr);
 #ifdef CONFIG_SYSCTL
-	devinet_sysctl.sysctl_header =
-		register_sysctl_table(devinet_sysctl.devinet_root_dir);
-	devinet_sysctl_register(NULL, &ipv4_devconf_dflt);
+	__devinet_sysctl_register("all", NET_PROTO_CONF_ALL,
+			&ipv4_devconf);
+	__devinet_sysctl_register("default", NET_PROTO_CONF_DEFAULT,
+			&ipv4_devconf_dflt);
 #endif
 }