[NET]: Rework dev_base via list_head (v3)

Cleanup of dev_base list use, with the aim to simplify making device
list per-namespace. In almost every occasion, use of dev_base variable
and dev->next pointer could be easily replaced by for_each_netdev
loop. A few most complicated places were converted to using
first_netdev()/next_netdev().

Signed-off-by: Pavel Emelianov <xemul@openvz.org>
Acked-by: Kirill Korotaev <dev@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 3452433..d02685c 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -449,7 +449,7 @@
 	struct inet6_dev *idev;
 
 	read_lock(&dev_base_lock);
-	for (dev=dev_base; dev; dev=dev->next) {
+	for_each_netdev(dev) {
 		rcu_read_lock();
 		idev = __in6_dev_get(dev);
 		if (idev) {
@@ -911,7 +911,7 @@
 	read_lock(&dev_base_lock);
 	rcu_read_lock();
 
-	for (dev = dev_base; dev; dev=dev->next) {
+	for_each_netdev(dev) {
 		struct inet6_dev *idev;
 		struct inet6_ifaddr *ifa;
 
@@ -2064,7 +2064,7 @@
 		return;
 	}
 
-	for (dev = dev_base; dev != NULL; dev = dev->next) {
+	for_each_netdev(dev) {
 		struct in_device * in_dev = __in_dev_get_rtnl(dev);
 		if (in_dev && (dev->flags & IFF_UP)) {
 			struct in_ifaddr * ifa;
@@ -2225,7 +2225,7 @@
 			return;
 	}
 	/* then try to inherit it from any device */
-	for (link_dev = dev_base; link_dev; link_dev = link_dev->next) {
+	for_each_netdev(link_dev) {
 		if (!ipv6_inherit_linklocal(idev, link_dev))
 			return;
 	}
@@ -3257,14 +3257,15 @@
 	s_idx = cb->args[0];
 	s_ip_idx = ip_idx = cb->args[1];
 
-	for (dev = dev_base, idx = 0; dev; dev = dev->next, idx++) {
+	idx = 0;
+	for_each_netdev(dev) {
 		if (idx < s_idx)
-			continue;
+			goto cont;
 		if (idx > s_idx)
 			s_ip_idx = 0;
 		ip_idx = 0;
 		if ((idev = in6_dev_get(dev)) == NULL)
-			continue;
+			goto cont;
 		read_lock_bh(&idev->lock);
 		switch (type) {
 		case UNICAST_ADDR:
@@ -3311,6 +3312,8 @@
 		}
 		read_unlock_bh(&idev->lock);
 		in6_dev_put(idev);
+cont:
+		idx++;
 	}
 done:
 	if (err <= 0) {
@@ -3575,16 +3578,19 @@
 	struct inet6_dev *idev;
 
 	read_lock(&dev_base_lock);
-	for (dev=dev_base, idx=0; dev; dev = dev->next, idx++) {
+	idx = 0;
+	for_each_netdev(dev) {
 		if (idx < s_idx)
-			continue;
+			goto cont;
 		if ((idev = in6_dev_get(dev)) == NULL)
-			continue;
+			goto cont;
 		err = inet6_fill_ifinfo(skb, idev, NETLINK_CB(cb->skb).pid,
 				cb->nlh->nlmsg_seq, RTM_NEWLINK, NLM_F_MULTI);
 		in6_dev_put(idev);
 		if (err <= 0)
 			break;
+cont:
+		idx++;
 	}
 	read_unlock(&dev_base_lock);
 	cb->args[0] = idx;
@@ -4247,7 +4253,7 @@
 	 *	clean dev list.
 	 */
 
-	for (dev=dev_base; dev; dev=dev->next) {
+	for_each_netdev(dev) {
 		if ((idev = __in6_dev_get(dev)) == NULL)
 			continue;
 		addrconf_ifdown(dev, 1);
diff --git a/net/ipv6/anycast.c b/net/ipv6/anycast.c
index 09117d6..9b81264 100644
--- a/net/ipv6/anycast.c
+++ b/net/ipv6/anycast.c
@@ -423,14 +423,18 @@
  */
 int ipv6_chk_acast_addr(struct net_device *dev, struct in6_addr *addr)
 {
+	int found = 0;
+
 	if (dev)
 		return ipv6_chk_acast_dev(dev, addr);
 	read_lock(&dev_base_lock);
-	for (dev=dev_base; dev; dev=dev->next)
-		if (ipv6_chk_acast_dev(dev, addr))
+	for_each_netdev(dev)
+		if (ipv6_chk_acast_dev(dev, addr)) {
+			found = 1;
 			break;
+		}
 	read_unlock(&dev_base_lock);
-	return dev != 0;
+	return found;
 }
 
 
@@ -447,9 +451,8 @@
 	struct ifacaddr6 *im = NULL;
 	struct ac6_iter_state *state = ac6_seq_private(seq);
 
-	for (state->dev = dev_base, state->idev = NULL;
-	     state->dev;
-	     state->dev = state->dev->next) {
+	state->idev = NULL;
+	for_each_netdev(state->dev) {
 		struct inet6_dev *idev;
 		idev = in6_dev_get(state->dev);
 		if (!idev)
@@ -476,7 +479,7 @@
 			read_unlock_bh(&state->idev->lock);
 			in6_dev_put(state->idev);
 		}
-		state->dev = state->dev->next;
+		state->dev = next_net_device(state->dev);
 		if (!state->dev) {
 			state->idev = NULL;
 			break;
diff --git a/net/ipv6/mcast.c b/net/ipv6/mcast.c
index 6c27589..3e308fb 100644
--- a/net/ipv6/mcast.c
+++ b/net/ipv6/mcast.c
@@ -2331,9 +2331,8 @@
 	struct ifmcaddr6 *im = NULL;
 	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
 
-	for (state->dev = dev_base, state->idev = NULL;
-	     state->dev;
-	     state->dev = state->dev->next) {
+	state->idev = NULL;
+	for_each_netdev(state->dev) {
 		struct inet6_dev *idev;
 		idev = in6_dev_get(state->dev);
 		if (!idev)
@@ -2360,7 +2359,7 @@
 			read_unlock_bh(&state->idev->lock);
 			in6_dev_put(state->idev);
 		}
-		state->dev = state->dev->next;
+		state->dev = next_net_device(state->dev);
 		if (!state->dev) {
 			state->idev = NULL;
 			break;
@@ -2475,9 +2474,9 @@
 	struct ifmcaddr6 *im = NULL;
 	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
 
-	for (state->dev = dev_base, state->idev = NULL, state->im = NULL;
-	     state->dev;
-	     state->dev = state->dev->next) {
+	state->idev = NULL;
+	state->im = NULL;
+	for_each_netdev(state->dev) {
 		struct inet6_dev *idev;
 		idev = in6_dev_get(state->dev);
 		if (unlikely(idev == NULL))
@@ -2513,7 +2512,7 @@
 				read_unlock_bh(&state->idev->lock);
 				in6_dev_put(state->idev);
 			}
-			state->dev = state->dev->next;
+			state->dev = next_net_device(state->dev);
 			if (!state->dev) {
 				state->idev = NULL;
 				goto out;