[RTNETLINK]: Introduce generic rtnl_create_link().

This routine gets the parsed rtnl attributes and creates a new
link with generic info (IFLA_LINKINFO policy). Its intention
is to help the drivers, that need to create several links at
once (like VETH).

This is nothing but a copy-paste-ed part of rtnl_newlink() function
that is responsible for creation of new device.

Signed-off-by: Pavel Emelianov <xemul@openvz.org>
Acked-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/net/rtnetlink.h b/include/net/rtnetlink.h
index 3861c05..8218288 100644 (file)
--- a/include/net/rtnetlink.h
+++ b/include/net/rtnetlink.h
@@ -78,6 +78,10 @@ extern void  __rtnl_link_unregister(struct rtnl_link_ops *ops);
 extern int     rtnl_link_register(struct rtnl_link_ops *ops);
 extern void    rtnl_link_unregister(struct rtnl_link_ops *ops);
 
+extern struct net_device *rtnl_create_link(char *ifname,
+               const struct rtnl_link_ops *ops, struct nlattr *tb[]);
+extern const struct nla_policy ifla_policy[IFLA_MAX+1];
+
 #define MODULE_ALIAS_RTNL_LINK(kind) MODULE_ALIAS("rtnl-link-" kind)
 
 #endif

diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 2b0b6fa..dca9e80 100644 (file)
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -713,7 +713,7 @@ cont:
        return skb->len;
 }
 
-static const struct nla_policy ifla_policy[IFLA_MAX+1] = {
+const struct nla_policy ifla_policy[IFLA_MAX+1] = {
        [IFLA_IFNAME]           = { .type = NLA_STRING, .len = IFNAMSIZ-1 },
        [IFLA_ADDRESS]          = { .type = NLA_BINARY, .len = MAX_ADDR_LEN },
        [IFLA_BROADCAST]        = { .type = NLA_BINARY, .len = MAX_ADDR_LEN },
@@ -937,6 +937,48 @@ static int rtnl_dellink(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
        return 0;
 }
 
+struct net_device *rtnl_create_link(char *ifname,
+               const struct rtnl_link_ops *ops, struct nlattr *tb[])
+{
+       int err;
+       struct net_device *dev;
+
+       err = -ENOMEM;
+       dev = alloc_netdev(ops->priv_size, ifname, ops->setup);
+       if (!dev)
+               goto err;
+
+       if (strchr(dev->name, '%')) {
+               err = dev_alloc_name(dev, dev->name);
+               if (err < 0)
+                       goto err_free;
+       }
+
+       dev->rtnl_link_ops = ops;
+
+       if (tb[IFLA_MTU])
+               dev->mtu = nla_get_u32(tb[IFLA_MTU]);
+       if (tb[IFLA_ADDRESS])
+               memcpy(dev->dev_addr, nla_data(tb[IFLA_ADDRESS]),
+                               nla_len(tb[IFLA_ADDRESS]));
+       if (tb[IFLA_BROADCAST])
+               memcpy(dev->broadcast, nla_data(tb[IFLA_BROADCAST]),
+                               nla_len(tb[IFLA_BROADCAST]));
+       if (tb[IFLA_TXQLEN])
+               dev->tx_queue_len = nla_get_u32(tb[IFLA_TXQLEN]);
+       if (tb[IFLA_OPERSTATE])
+               set_operstate(dev, nla_get_u8(tb[IFLA_OPERSTATE]));
+       if (tb[IFLA_LINKMODE])
+               dev->link_mode = nla_get_u8(tb[IFLA_LINKMODE]);
+
+       return dev;
+
+err_free:
+       free_netdev(dev);
+err:
+       return ERR_PTR(err);
+}
+
 static int rtnl_newlink(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 {
        const struct rtnl_link_ops *ops;
@@ -1049,38 +1091,17 @@ replay:
 
                if (!ifname[0])
                        snprintf(ifname, IFNAMSIZ, "%s%%d", ops->kind);
-               dev = alloc_netdev(ops->priv_size, ifname, ops->setup);
-               if (!dev)
-                       return -ENOMEM;
-
-               if (strchr(dev->name, '%')) {
-                       err = dev_alloc_name(dev, dev->name);
-                       if (err < 0)
-                               goto err_free;
-               }
-               dev->rtnl_link_ops = ops;
-
-               if (tb[IFLA_MTU])
-                       dev->mtu = nla_get_u32(tb[IFLA_MTU]);
-               if (tb[IFLA_ADDRESS])
-                       memcpy(dev->dev_addr, nla_data(tb[IFLA_ADDRESS]),
-                              nla_len(tb[IFLA_ADDRESS]));
-               if (tb[IFLA_BROADCAST])
-                       memcpy(dev->broadcast, nla_data(tb[IFLA_BROADCAST]),
-                              nla_len(tb[IFLA_BROADCAST]));
-               if (tb[IFLA_TXQLEN])
-                       dev->tx_queue_len = nla_get_u32(tb[IFLA_TXQLEN]);
-               if (tb[IFLA_OPERSTATE])
-                       set_operstate(dev, nla_get_u8(tb[IFLA_OPERSTATE]));
-               if (tb[IFLA_LINKMODE])
-                       dev->link_mode = nla_get_u8(tb[IFLA_LINKMODE]);
-
-               if (ops->newlink)
+
+               dev = rtnl_create_link(ifname, ops, tb);
+
+               if (IS_ERR(dev))
+                       err = PTR_ERR(dev);
+               else if (ops->newlink)
                        err = ops->newlink(dev, tb, data);
                else
                        err = register_netdevice(dev);
-err_free:
-               if (err < 0)
+
+               if (err < 0 && !IS_ERR(dev))
                        free_netdev(dev);
                return err;
        }
@@ -1329,3 +1350,5 @@ EXPORT_SYMBOL(rtnl_unlock);
 EXPORT_SYMBOL(rtnl_unicast);
 EXPORT_SYMBOL(rtnl_notify);
 EXPORT_SYMBOL(rtnl_set_sk_err);
+EXPORT_SYMBOL(rtnl_create_link);
+EXPORT_SYMBOL(ifla_policy);