net/l3mdev/l3mdev.c

   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);