[NET]: Make some network-related proc files use seq_list_xxx helpers

This includes /proc/net/protocols, /proc/net/rxrpc_calls and
/proc/net/rxrpc_connections files.

All three need seq_list_start_head to show some header.
Signed-off-by: Pavel Emelianov <xemul@openvz.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/core/sock.c

@@ -1851,46 +1851,15 @@ void proto_unregister(struct proto *prot)
 EXPORT_SYMBOL(proto_unregister);
 
 #ifdef CONFIG_PROC_FS
-static inline struct proto *__proto_head(void)
-{
-	return list_entry(proto_list.next, struct proto, node);
-}
-
-static inline struct proto *proto_head(void)
-{
-	return list_empty(&proto_list) ? NULL : __proto_head();
-}
-
-static inline struct proto *proto_next(struct proto *proto)
-{
-	return proto->node.next == &proto_list ? NULL :
-		list_entry(proto->node.next, struct proto, node);
-}
-
-static inline struct proto *proto_get_idx(loff_t pos)
-{
-	struct proto *proto;
-	loff_t i = 0;
-
-	list_for_each_entry(proto, &proto_list, node)
-		if (i++ == pos)
-			goto out;
-
-	proto = NULL;
-out:
-	return proto;
-}
-
 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
 {
 	read_lock(&proto_list_lock);
-	return *pos ? proto_get_idx(*pos - 1) : SEQ_START_TOKEN;
+	return seq_list_start_head(&proto_list, *pos);
 }
 
 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 {
-	++*pos;
-	return v == SEQ_START_TOKEN ? proto_head() : proto_next(v);
+	return seq_list_next(v, &proto_list, pos);
 }
 
 static void proto_seq_stop(struct seq_file *seq, void *v)
@@ -1938,7 +1907,7 @@ static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
 
 static int proto_seq_show(struct seq_file *seq, void *v)
 {
-	if (v == SEQ_START_TOKEN)
+	if (v == &proto_list)
 		seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
 			   "protocol",
 			   "size",
@@ -1950,7 +1919,7 @@ static int proto_seq_show(struct seq_file *seq, void *v)
 			   "module",
 			   "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
 	else
-		proto_seq_printf(seq, v);
+		proto_seq_printf(seq, list_entry(v, struct proto, node));
 	return 0;
 }
 

net/rxrpc/ar-proc.c

@@ -30,31 +30,13 @@ static const char *rxrpc_conn_states[] = {
  */
 static void *rxrpc_call_seq_start(struct seq_file *seq, loff_t *_pos)
 {
-	struct list_head *_p;
-	loff_t pos = *_pos;
-
 	read_lock(&rxrpc_call_lock);
-	if (!pos)
-		return SEQ_START_TOKEN;
-	pos--;
-
-	list_for_each(_p, &rxrpc_calls)
-		if (!pos--)
-			break;
-
-	return _p != &rxrpc_calls ? _p : NULL;
+	return seq_list_start_head(&rxrpc_calls, *_pos);
 }
 
 static void *rxrpc_call_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 {
-	struct list_head *_p;
-
-	(*pos)++;
-
-	_p = v;
-	_p = (v == SEQ_START_TOKEN) ? rxrpc_calls.next : _p->next;
-
-	return _p != &rxrpc_calls ? _p : NULL;
+	return seq_list_next(v, &rxrpc_calls, pos);
 }
 
 static void rxrpc_call_seq_stop(struct seq_file *seq, void *v)
@@ -68,7 +50,7 @@ static int rxrpc_call_seq_show(struct seq_file *seq, void *v)
 	struct rxrpc_call *call;
 	char lbuff[4 + 4 + 4 + 4 + 5 + 1], rbuff[4 + 4 + 4 + 4 + 5 + 1];
 
-	if (v == SEQ_START_TOKEN) {
+	if (v == &rxrpc_calls) {
 		seq_puts(seq,
 			 "Proto Local                  Remote                "
 			 " SvID ConnID   CallID   End Use State    Abort   "
@@ -129,32 +111,14 @@ struct file_operations rxrpc_call_seq_fops = {
  */
 static void *rxrpc_connection_seq_start(struct seq_file *seq, loff_t *_pos)
 {
-	struct list_head *_p;
-	loff_t pos = *_pos;
-
 	read_lock(&rxrpc_connection_lock);
-	if (!pos)
-		return SEQ_START_TOKEN;
-	pos--;
-
-	list_for_each(_p, &rxrpc_connections)
-		if (!pos--)
-			break;
-
-	return _p != &rxrpc_connections ? _p : NULL;
+	return seq_list_start_head(&rxrpc_connections, *_pos);
 }
 
 static void *rxrpc_connection_seq_next(struct seq_file *seq, void *v,
 				       loff_t *pos)
 {
-	struct list_head *_p;
-
-	(*pos)++;
-
-	_p = v;
-	_p = (v == SEQ_START_TOKEN) ? rxrpc_connections.next : _p->next;
-
-	return _p != &rxrpc_connections ? _p : NULL;
+	return seq_list_next(v, &rxrpc_connections, pos);
 }
 
 static void rxrpc_connection_seq_stop(struct seq_file *seq, void *v)
@@ -168,7 +132,7 @@ static int rxrpc_connection_seq_show(struct seq_file *seq, void *v)
 	struct rxrpc_transport *trans;
 	char lbuff[4 + 4 + 4 + 4 + 5 + 1], rbuff[4 + 4 + 4 + 4 + 5 + 1];
 
-	if (v == SEQ_START_TOKEN) {
+	if (v == &rxrpc_connections) {
 		seq_puts(seq,
 			 "Proto Local                  Remote                "
 			 " SvID ConnID   Calls    End Use State    Key     "