net: rtnetlink: add linkprop commands to add and delete alternative ifnames

Add two commands to add and delete list of link properties. Implement
the first property type along - alternative ifnames.
Each net device can have multiple alternative names.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 57 insertions, 1 deletions

diff --git a/net/core/dev.c b/net/core/dev.c
index d2053d07c94a..7a456c6a7ad8 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -245,7 +245,13 @@ static struct netdev_name_node *netdev_name_node_alloc(struct net_device *dev,
 static struct netdev_name_node *
 netdev_name_node_head_alloc(struct net_device *dev)
 {
-	return netdev_name_node_alloc(dev, dev->name);
+	struct netdev_name_node *name_node;
+
+	name_node = netdev_name_node_alloc(dev, dev->name);
+	if (!name_node)
+		return NULL;
+	INIT_LIST_HEAD(&name_node->list);
+	return name_node;
 }
 
 static void netdev_name_node_free(struct netdev_name_node *name_node)
@@ -289,6 +295,55 @@ static struct netdev_name_node *netdev_name_node_lookup_rcu(struct net *net,
 	return NULL;
 }
 
+int netdev_name_node_alt_create(struct net_device *dev, const char *name)
+{
+	struct netdev_name_node *name_node;
+	struct net *net = dev_net(dev);
+
+	name_node = netdev_name_node_lookup(net, name);
+	if (name_node)
+		return -EEXIST;
+	name_node = netdev_name_node_alloc(dev, name);
+	if (!name_node)
+		return -ENOMEM;
+	netdev_name_node_add(net, name_node);
+	/* The node that holds dev->name acts as a head of per-device list. */
+	list_add_tail(&name_node->list, &dev->name_node->list);
+
+	return 0;
+}
+EXPORT_SYMBOL(netdev_name_node_alt_create);
+
+static void __netdev_name_node_alt_destroy(struct netdev_name_node *name_node)
+{
+	list_del(&name_node->list);
+	netdev_name_node_del(name_node);
+	kfree(name_node->name);
+	netdev_name_node_free(name_node);
+}
+
+int netdev_name_node_alt_destroy(struct net_device *dev, const char *name)
+{
+	struct netdev_name_node *name_node;
+	struct net *net = dev_net(dev);
+
+	name_node = netdev_name_node_lookup(net, name);
+	if (!name_node)
+		return -ENOENT;
+	__netdev_name_node_alt_destroy(name_node);
+
+	return 0;
+}
+EXPORT_SYMBOL(netdev_name_node_alt_destroy);
+
+static void netdev_name_node_alt_flush(struct net_device *dev)
+{
+	struct netdev_name_node *name_node, *tmp;
+
+	list_for_each_entry_safe(name_node, tmp, &dev->name_node->list, list)
+		__netdev_name_node_alt_destroy(name_node);
+}
+
 /* Device list insertion */
 static void list_netdevice(struct net_device *dev)
 {
@@ -8317,6 +8372,7 @@ static void rollback_registered_many(struct list_head *head)
 		dev_uc_flush(dev);
 		dev_mc_flush(dev);
 
+		netdev_name_node_alt_flush(dev);
 		netdev_name_node_free(dev->name_node);
 
 		if (dev->netdev_ops->ndo_uninit)