include/net/l3mdev.h

   1 /*
   2  * include/net/l3mdev.h - L3 master device API
   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 #ifndef _NET_L3MDEV_H_
  12 #define _NET_L3MDEV_H_
  13
  14 /**
  15  * struct l3mdev_ops - l3mdev operations
  16  *
  17  * @l3mdev_fib_table: Get FIB table id to use for lookups
  18  *
  19  * @l3mdev_get_rtable: Get cached IPv4 rtable (dst_entry) for device
  20  *
  21  * @l3mdev_get_saddr: Get source address for a flow
  22  */
  23
  24 struct l3mdev_ops {
  25         u32             (*l3mdev_fib_table)(const struct net_device *dev);
  26         struct rtable * (*l3mdev_get_rtable)(const struct net_device *dev,
  27                                              const struct flowi4 *fl4);
  28         void            (*l3mdev_get_saddr)(struct net_device *dev,
  29                                             struct flowi4 *fl4);
  30 };
  31
  32 #ifdef CONFIG_NET_L3_MASTER_DEV
  33
  34 int l3mdev_master_ifindex_rcu(struct net_device *dev);
  35 static inline int l3mdev_master_ifindex(struct net_device *dev)
  36 {
  37         int ifindex;
  38
  39         rcu_read_lock();
  40         ifindex = l3mdev_master_ifindex_rcu(dev);
  41         rcu_read_unlock();
  42
  43         return ifindex;
  44 }
  45
  46 /* get index of an interface to use for FIB lookups. For devices
  47  * enslaved to an L3 master device FIB lookups are based on the
  48  * master index
  49  */
  50 static inline int l3mdev_fib_oif_rcu(struct net_device *dev)
  51 {
  52         return l3mdev_master_ifindex_rcu(dev) ? : dev->ifindex;
  53 }
  54
  55 static inline int l3mdev_fib_oif(struct net_device *dev)
  56 {
  57         int oif;
  58
  59         rcu_read_lock();
  60         oif = l3mdev_fib_oif_rcu(dev);
  61         rcu_read_unlock();
  62
  63         return oif;
  64 }
  65
  66 u32 l3mdev_fib_table_rcu(const struct net_device *dev);
  67 u32 l3mdev_fib_table_by_index(struct net *net, int ifindex);
  68 static inline u32 l3mdev_fib_table(const struct net_device *dev)
  69 {
  70         u32 tb_id;
  71
  72         rcu_read_lock();
  73         tb_id = l3mdev_fib_table_rcu(dev);
  74         rcu_read_unlock();
  75
  76         return tb_id;
  77 }
  78
  79 static inline struct rtable *l3mdev_get_rtable(const struct net_device *dev,
  80                                                const struct flowi4 *fl4)
  81 {
  82         if (netif_is_l3_master(dev) && dev->l3mdev_ops->l3mdev_get_rtable)
  83                 return dev->l3mdev_ops->l3mdev_get_rtable(dev, fl4);
  84
  85         return NULL;
  86 }
  87
  88 static inline bool netif_index_is_l3_master(struct net *net, int ifindex)
  89 {
  90         struct net_device *dev;
  91         bool rc = false;
  92
  93         if (ifindex == 0)
  94                 return false;
  95
  96         rcu_read_lock();
  97
  98         dev = dev_get_by_index_rcu(net, ifindex);
  99         if (dev)
 100                 rc = netif_is_l3_master(dev);
 101
 102         rcu_read_unlock();
 103
 104         return rc;
 105 }
 106
 107 static inline void l3mdev_get_saddr(struct net *net, int ifindex,
 108                                     struct flowi4 *fl4)
 109 {
 110         struct net_device *dev;
 111
 112         if (ifindex) {
 113
 114                 rcu_read_lock();
 115
 116                 dev = dev_get_by_index_rcu(net, ifindex);
 117                 if (dev && netif_is_l3_master(dev) &&
 118                     dev->l3mdev_ops->l3mdev_get_saddr) {
 119                         dev->l3mdev_ops->l3mdev_get_saddr(dev, fl4);
 120                 }
 121
 122                 rcu_read_unlock();
 123         }
 124 }
 125
 126 #else
 127
 128 static inline int l3mdev_master_ifindex_rcu(struct net_device *dev)
 129 {
 130         return 0;
 131 }
 132 static inline int l3mdev_master_ifindex(struct net_device *dev)
 133 {
 134         return 0;
 135 }
 136
 137 static inline int l3mdev_fib_oif_rcu(struct net_device *dev)
 138 {
 139         return dev ? dev->ifindex : 0;
 140 }
 141 static inline int l3mdev_fib_oif(struct net_device *dev)
 142 {
 143         return dev ? dev->ifindex : 0;
 144 }
 145
 146 static inline u32 l3mdev_fib_table_rcu(const struct net_device *dev)
 147 {
 148         return 0;
 149 }
 150 static inline u32 l3mdev_fib_table(const struct net_device *dev)
 151 {
 152         return 0;
 153 }
 154 static inline u32 l3mdev_fib_table_by_index(struct net *net, int ifindex)
 155 {
 156         return 0;
 157 }
 158
 159 static inline struct rtable *l3mdev_get_rtable(const struct net_device *dev,
 160                                                const struct flowi4 *fl4)
 161 {
 162         return NULL;
 163 }
 164
 165 static inline bool netif_index_is_l3_master(struct net *net, int ifindex)
 166 {
 167         return false;
 168 }
 169
 170 static inline void l3mdev_get_saddr(struct net *net, int ifindex,
 171                                     struct flowi4 *fl4)
 172 {
 173 }
 174 #endif
 175
 176 #endif /* _NET_L3MDEV_H_ */