[PATCH] dynamic allocation for dummy net device

[Stephen Hemminger <shemminger@xxxxxxxx>]

Change dummy driver to dynamically allocate it's net_device using alloc_netdev.
This prevents problems later when network device objects persist after 
unregister.

--- linux-2.5/drivers/net/dummy.c       2003-06-12 13:35:41.000000000 -0700
+++ linux-2.5-dyn/drivers/net/dummy.c   2003-06-12 15:00:15.000000000 -0700
@@ -51,15 +51,9 @@ static int dummy_accept_fastpath(struct 
 }
 #endif
 
-static int __init dummy_init(struct net_device *dev)
+static void __init dummy_setup(struct net_device *dev)
 {
        /* Initialize the device structure. */
-
-       dev->priv = kmalloc(sizeof(struct net_device_stats), GFP_KERNEL);
-       if (dev->priv == NULL)
-               return -ENOMEM;
-       memset(dev->priv, 0, sizeof(struct net_device_stats));
-
        dev->get_stats = dummy_get_stats;
        dev->hard_start_xmit = dummy_xmit;
        dev->set_multicast_list = set_multicast_list;
@@ -72,8 +66,7 @@ static int __init dummy_init(struct net_
        dev->tx_queue_len = 0;
        dev->flags |= IFF_NOARP;
        dev->flags &= ~IFF_MULTICAST;
-
-       return 0;
+       SET_MODULE_OWNER(dev);
 }
 
 static int dummy_xmit(struct sk_buff *skb, struct net_device *dev)
@@ -92,32 +85,30 @@ static struct net_device_stats *dummy_ge
        return dev->priv;
 }
 
-static struct net_device dev_dummy;
+static struct net_device *dev_dummy;
 
 static int __init dummy_init_module(void)
 {
        int err;
 
-       dev_dummy.init = dummy_init;
-       SET_MODULE_OWNER(&dev_dummy);
+       dev_dummy = alloc_netdev(sizeof(struct net_device_stats),
+                                "dummy%d", dummy_setup);
 
-       /* Find a name for this unit */
-       err=dev_alloc_name(&dev_dummy,"dummy%d");
-       if(err<0)
-               return err;
-       err = register_netdev(&dev_dummy);
-       if (err<0)
-               return err;
-       return 0;
+       if (!dev_dummy)
+               return -ENOMEM;
+
+       if ((err = register_netdev(dev_dummy))) {
+               kfree(dev_dummy);
+               dev_dummy = NULL;
+       }
+       return err;
 }
 
 static void __exit dummy_cleanup_module(void)
 {
-       unregister_netdev(&dev_dummy);
-       kfree(dev_dummy.priv);
-
-       memset(&dev_dummy, 0, sizeof(dev_dummy));
-       dev_dummy.init = dummy_init;
+       unregister_netdev(dev_dummy);
+       kfree(dev_dummy);
+       dev_dummy = NULL;
 }
 
 module_init(dummy_init_module);