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  * @l3mdev_get_rt6_dst: Get cached IPv6 rt6_info (dst_entry) for device
  24  */
  25
  26 struct l3mdev_ops {
  27         u32             (*l3mdev_fib_table)(const struct net_device *dev);
  28
  29         /* IPv4 ops */
  30         struct rtable * (*l3mdev_get_rtable)(const struct net_device *dev,
  31                                              const struct flowi4 *fl4);
  32         int             (*l3mdev_get_saddr)(struct net_device *dev,
  33                                             struct flowi4 *fl4);
  34
  35         /* IPv6 ops */
  36         struct dst_entry * (*l3mdev_get_rt6_dst)(const struct net_device *dev,
  37                                                  const struct flowi6 *fl6);
  38 };
  39
  40 #ifdef CONFIG_NET_L3_MASTER_DEV
  41
  42 int l3mdev_master_ifindex_rcu(struct net_device *dev);
  43 static inline int l3mdev_master_ifindex(struct net_device *dev)
  44 {
  45         int ifindex;
  46
  47         rcu_read_lock();
  48         ifindex = l3mdev_master_ifindex_rcu(dev);
  49         rcu_read_unlock();
  50
  51         return ifindex;
  52 }
  53
  54 /* get index of an interface to use for FIB lookups. For devices
  55  * enslaved to an L3 master device FIB lookups are based on the
  56  * master index
  57  */
  58 static inline int l3mdev_fib_oif_rcu(struct net_device *dev)
  59 {
  60         return l3mdev_master_ifindex_rcu(dev) ? : dev->ifindex;
  61 }
  62
  63 static inline int l3mdev_fib_oif(struct net_device *dev)
  64 {
  65         int oif;
  66
  67         rcu_read_lock();
  68         oif = l3mdev_fib_oif_rcu(dev);
  69         rcu_read_unlock();
  70
  71         return oif;
  72 }
  73
  74 u32 l3mdev_fib_table_rcu(const struct net_device *dev);
  75 u32 l3mdev_fib_table_by_index(struct net *net, int ifindex);
  76 static inline u32 l3mdev_fib_table(const struct net_device *dev)
  77 {
  78         u32 tb_id;
  79
  80         rcu_read_lock();
  81         tb_id = l3mdev_fib_table_rcu(dev);
  82         rcu_read_unlock();
  83
  84         return tb_id;
  85 }
  86
  87 static inline struct rtable *l3mdev_get_rtable(const struct net_device *dev,
  88                                                const struct flowi4 *fl4)
  89 {
  90         if (netif_is_l3_master(dev) && dev->l3mdev_ops->l3mdev_get_rtable)
  91                 return dev->l3mdev_ops->l3mdev_get_rtable(dev, fl4);
  92
  93         return NULL;
  94 }
  95
  96 static inline bool netif_index_is_l3_master(struct net *net, int ifindex)
  97 {
  98         struct net_device *dev;
  99         bool rc = false;
 100
 101         if (ifindex == 0)
 102                 return false;
 103
 104         rcu_read_lock();
 105
 106         dev = dev_get_by_index_rcu(net, ifindex);
 107         if (dev)
 108                 rc = netif_is_l3_master(dev);
 109
 110         rcu_read_unlock();
 111
 112         return rc;
 113 }
 114
 115 static inline int l3mdev_get_saddr(struct net *net, int ifindex,
 116                                    struct flowi4 *fl4)
 117 {
 118         struct net_device *dev;
 119         int rc = 0;
 120
 121         if (ifindex) {
 122
 123                 rcu_read_lock();
 124
 125                 dev = dev_get_by_index_rcu(net, ifindex);
 126                 if (dev && netif_is_l3_master(dev) &&
 127                     dev->l3mdev_ops->l3mdev_get_saddr) {
 128                         rc = dev->l3mdev_ops->l3mdev_get_saddr(dev, fl4);
 129                 }
 130
 131                 rcu_read_unlock();
 132         }
 133
 134         return rc;
 135 }
 136
 137 static inline struct dst_entry *l3mdev_get_rt6_dst(const struct net_device *dev,
 138                                                    const struct flowi6 *fl6)
 139 {
 140         if (netif_is_l3_master(dev) && dev->l3mdev_ops->l3mdev_get_rt6_dst)
 141                 return dev->l3mdev_ops->l3mdev_get_rt6_dst(dev, fl6);
 142
 143         return NULL;
 144 }
 145
 146 static inline
 147 struct dst_entry *l3mdev_rt6_dst_by_oif(struct net *net,
 148                                         const struct flowi6 *fl6)
 149 {
 150         struct dst_entry *dst = NULL;
 151         struct net_device *dev;
 152
 153         dev = dev_get_by_index(net, fl6->flowi6_oif);
 154         if (dev) {
 155                 dst = l3mdev_get_rt6_dst(dev, fl6);
 156                 dev_put(dev);
 157         }
 158
 159         return dst;
 160 }
 161
 162 #else
 163
 164 static inline int l3mdev_master_ifindex_rcu(struct net_device *dev)
 165 {
 166         return 0;
 167 }
 168 static inline int l3mdev_master_ifindex(struct net_device *dev)
 169 {
 170         return 0;
 171 }
 172
 173 static inline int l3mdev_fib_oif_rcu(struct net_device *dev)
 174 {
 175         return dev ? dev->ifindex : 0;
 176 }
 177 static inline int l3mdev_fib_oif(struct net_device *dev)
 178 {
 179         return dev ? dev->ifindex : 0;
 180 }
 181
 182 static inline u32 l3mdev_fib_table_rcu(const struct net_device *dev)
 183 {
 184         return 0;
 185 }
 186 static inline u32 l3mdev_fib_table(const struct net_device *dev)
 187 {
 188         return 0;
 189 }
 190 static inline u32 l3mdev_fib_table_by_index(struct net *net, int ifindex)
 191 {
 192         return 0;
 193 }
 194
 195 static inline struct rtable *l3mdev_get_rtable(const struct net_device *dev,
 196                                                const struct flowi4 *fl4)
 197 {
 198         return NULL;
 199 }
 200
 201 static inline bool netif_index_is_l3_master(struct net *net, int ifindex)
 202 {
 203         return false;
 204 }
 205
 206 static inline int l3mdev_get_saddr(struct net *net, int ifindex,
 207                                    struct flowi4 *fl4)
 208 {
 209         return 0;
 210 }
 211
 212 static inline
 213 struct dst_entry *l3mdev_get_rt6_dst(const struct net_device *dev,
 214                                      const struct flowi6 *fl6)
 215 {
 216         return NULL;
 217 }
 218 static inline
 219 struct dst_entry *l3mdev_rt6_dst_by_oif(struct net *net,
 220                                         const struct flowi6 *fl6)
 221 {
 222         return NULL;
 223 }
 224 #endif
 225
 226 #endif /* _NET_L3MDEV_H_ */