net: Simplify ppp_generic pernet operations.

Take advantage of the new pernet automatic storage management,
and stop using compatibility network namespace functions.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ppp_generic.c

@@ -864,12 +864,7 @@ static const struct file_operations ppp_device_fops = {
 
 static __net_init int ppp_init_net(struct net *net)
 {
-	struct ppp_net *pn;
-	int err;
-
-	pn = kzalloc(sizeof(*pn), GFP_KERNEL);
-	if (!pn)
-		return -ENOMEM;
+	struct ppp_net *pn = net_generic(net, ppp_net_id);
 
 	idr_init(&pn->units_idr);
 	mutex_init(&pn->all_ppp_mutex);
@@ -879,32 +874,21 @@ static __net_init int ppp_init_net(struct net *net)
 
 	spin_lock_init(&pn->all_channels_lock);
 
-	err = net_assign_generic(net, ppp_net_id, pn);
-	if (err) {
-		kfree(pn);
-		return err;
-	}
-
 	return 0;
 }
 
 static __net_exit void ppp_exit_net(struct net *net)
 {
-	struct ppp_net *pn;
+	struct ppp_net *pn = net_generic(net, ppp_net_id);
 
-	pn = net_generic(net, ppp_net_id);
 	idr_destroy(&pn->units_idr);
-	/*
-	 * if someone has cached our net then
-	 * further net_generic call will return NULL
-	 */
-	net_assign_generic(net, ppp_net_id, NULL);
-	kfree(pn);
 }
 
 static struct pernet_operations ppp_net_ops = {
 	.init = ppp_init_net,
 	.exit = ppp_exit_net,
+	.id   = &ppp_net_id,
+	.size = sizeof(struct ppp_net),
 };
 
 #define PPP_MAJOR	108
@@ -917,7 +901,7 @@ static int __init ppp_init(void)
 
 	printk(KERN_INFO "PPP generic driver version " PPP_VERSION "\n");
 
-	err = register_pernet_gen_device(&ppp_net_id, &ppp_net_ops);
+	err = register_pernet_device(&ppp_net_ops);
 	if (err) {
 		printk(KERN_ERR "failed to register PPP pernet device (%d)\n", err);
 		goto out;
@@ -943,7 +927,7 @@ static int __init ppp_init(void)
 out_chrdev:
 	unregister_chrdev(PPP_MAJOR, "ppp");
 out_net:
-	unregister_pernet_gen_device(ppp_net_id, &ppp_net_ops);
+	unregister_pernet_device(&ppp_net_ops);
 out:
 	return err;
 }
@@ -2835,7 +2819,7 @@ static void __exit ppp_cleanup(void)
 	unregister_chrdev(PPP_MAJOR, "ppp");
 	device_destroy(ppp_class, MKDEV(PPP_MAJOR, 0));
 	class_destroy(ppp_class);
-	unregister_pernet_gen_device(ppp_net_id, &ppp_net_ops);
+	unregister_pernet_device(&ppp_net_ops);
 }
 
 /*