netns: assign PDE->data before gluing entry into /proc tree

In this unfortunate case, proc_mkdir_mode wrapper can't be used anymore and
this is no way to reuse proc_create_data due to nlinks assignment. So,
copy the code from proc_mkdir and assign PDE->data at the appropriate
moment.
Signed-off-by: NDenis V. Lunev <den@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

fs/proc/generic.c

@@ -641,6 +641,23 @@ struct proc_dir_entry *proc_mkdir_mode(const char *name, mode_t mode,
 	return ent;
 }
 
+struct proc_dir_entry *proc_net_mkdir(struct net *net, const char *name,
+		struct proc_dir_entry *parent)
+{
+	struct proc_dir_entry *ent;
+
+	ent = __proc_create(&parent, name, S_IFDIR | S_IRUGO | S_IXUGO, 2);
+	if (ent) {
+		ent->data = net;
+		if (proc_register(parent, ent) < 0) {
+			kfree(ent);
+			ent = NULL;
+		}
+	}
+	return ent;
+}
+EXPORT_SYMBOL_GPL(proc_net_mkdir);
+
 struct proc_dir_entry *proc_mkdir(const char *name,
 		struct proc_dir_entry *parent)
 {

fs/proc/proc_net.c

@@ -159,17 +159,6 @@ struct net *get_proc_net(const struct inode *inode)
 }
 EXPORT_SYMBOL_GPL(get_proc_net);
 
-struct proc_dir_entry *proc_net_mkdir(struct net *net, const char *name,
-		struct proc_dir_entry *parent)
-{
-	struct proc_dir_entry *pde;
-	pde = proc_mkdir_mode(name, S_IRUGO | S_IXUGO, parent);
-	if (pde != NULL)
-		pde->data = net;
-	return pde;
-}
-EXPORT_SYMBOL_GPL(proc_net_mkdir);
-
 static __net_init int proc_net_ns_init(struct net *net)
 {
 	struct proc_dir_entry *netd, *net_statd;