net: ipv4: route.c: simplify procfs code

proc_creat_seq() that directly take a struct seq_operations,
and deal with network namespaces in ->open.
Signed-off-by: Yejune Deng <yejune.deng@gmail.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv4/route.c

@@ -234,19 +234,6 @@ static const struct seq_operations rt_cache_seq_ops = {
 	.show   = rt_cache_seq_show,
 };
 
-static int rt_cache_seq_open(struct inode *inode, struct file *file)
-{
-	return seq_open(file, &rt_cache_seq_ops);
-}
-
-static const struct proc_ops rt_cache_proc_ops = {
-	.proc_open	= rt_cache_seq_open,
-	.proc_read	= seq_read,
-	.proc_lseek	= seq_lseek,
-	.proc_release	= seq_release,
-};
-
-
 static void *rt_cpu_seq_start(struct seq_file *seq, loff_t *pos)
 {
 	int cpu;
@@ -324,19 +311,6 @@ static const struct seq_operations rt_cpu_seq_ops = {
 	.show   = rt_cpu_seq_show,
 };
 
-
-static int rt_cpu_seq_open(struct inode *inode, struct file *file)
-{
-	return seq_open(file, &rt_cpu_seq_ops);
-}
-
-static const struct proc_ops rt_cpu_proc_ops = {
-	.proc_open	= rt_cpu_seq_open,
-	.proc_read	= seq_read,
-	.proc_lseek	= seq_lseek,
-	.proc_release	= seq_release,
-};
-
 #ifdef CONFIG_IP_ROUTE_CLASSID
 static int rt_acct_proc_show(struct seq_file *m, void *v)
 {
@@ -367,13 +341,13 @@ static int __net_init ip_rt_do_proc_init(struct net *net)
 {
 	struct proc_dir_entry *pde;
 
-	pde = proc_create("rt_cache", 0444, net->proc_net,
-			  &rt_cache_proc_ops);
+	pde = proc_create_seq("rt_cache", 0444, net->proc_net,
+			      &rt_cache_seq_ops);
 	if (!pde)
 		goto err1;
 
-	pde = proc_create("rt_cache", 0444,
-			  net->proc_net_stat, &rt_cpu_proc_ops);
+	pde = proc_create_seq("rt_cache", 0444, net->proc_net_stat,
+			      &rt_cpu_seq_ops);
 	if (!pde)
 		goto err2;