xref: /openbmc/linux/net/l3mdev/l3mdev.c (revision cc8bbe1a)
1 /*
2  * net/l3mdev/l3mdev.c - L3 master device implementation
3  * Copyright (c) 2015 Cumulus Networks
4  * Copyright (c) 2015 David Ahern <dsa@cumulusnetworks.com>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  */
11 
12 #include <linux/netdevice.h>
13 #include <net/l3mdev.h>
14 
15 /**
16  *	l3mdev_master_ifindex - get index of L3 master device
17  *	@dev: targeted interface
18  */
19 
20 int l3mdev_master_ifindex_rcu(struct net_device *dev)
21 {
22 	int ifindex = 0;
23 
24 	if (!dev)
25 		return 0;
26 
27 	if (netif_is_l3_master(dev)) {
28 		ifindex = dev->ifindex;
29 	} else if (netif_is_l3_slave(dev)) {
30 		struct net_device *master;
31 
32 		master = netdev_master_upper_dev_get_rcu(dev);
33 		if (master)
34 			ifindex = master->ifindex;
35 	}
36 
37 	return ifindex;
38 }
39 EXPORT_SYMBOL_GPL(l3mdev_master_ifindex_rcu);
40 
41 /**
42  *	l3mdev_fib_table - get FIB table id associated with an L3
43  *                             master interface
44  *	@dev: targeted interface
45  */
46 
47 u32 l3mdev_fib_table_rcu(const struct net_device *dev)
48 {
49 	u32 tb_id = 0;
50 
51 	if (!dev)
52 		return 0;
53 
54 	if (netif_is_l3_master(dev)) {
55 		if (dev->l3mdev_ops->l3mdev_fib_table)
56 			tb_id = dev->l3mdev_ops->l3mdev_fib_table(dev);
57 	} else if (netif_is_l3_slave(dev)) {
58 		/* Users of netdev_master_upper_dev_get_rcu need non-const,
59 		 * but current inet_*type functions take a const
60 		 */
61 		struct net_device *_dev = (struct net_device *) dev;
62 		const struct net_device *master;
63 
64 		master = netdev_master_upper_dev_get_rcu(_dev);
65 		if (master &&
66 		    master->l3mdev_ops->l3mdev_fib_table)
67 			tb_id = master->l3mdev_ops->l3mdev_fib_table(master);
68 	}
69 
70 	return tb_id;
71 }
72 EXPORT_SYMBOL_GPL(l3mdev_fib_table_rcu);
73 
74 u32 l3mdev_fib_table_by_index(struct net *net, int ifindex)
75 {
76 	struct net_device *dev;
77 	u32 tb_id = 0;
78 
79 	if (!ifindex)
80 		return 0;
81 
82 	rcu_read_lock();
83 
84 	dev = dev_get_by_index_rcu(net, ifindex);
85 	if (dev)
86 		tb_id = l3mdev_fib_table_rcu(dev);
87 
88 	rcu_read_unlock();
89 
90 	return tb_id;
91 }
92 EXPORT_SYMBOL_GPL(l3mdev_fib_table_by_index);
93