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 static inline int l3mdev_master_ifindex_by_index(struct net *net, int ifindex)
  55 {
  56         struct net_device *dev;
  57         int rc = 0;
  58
  59         if (likely(ifindex)) {
  60                 rcu_read_lock();
  61
  62                 dev = dev_get_by_index_rcu(net, ifindex);
  63                 if (dev)
  64                         rc = l3mdev_master_ifindex_rcu(dev);
  65
  66                 rcu_read_unlock();
  67         }
  68
  69         return rc;
  70 }
  71
  72 /* get index of an interface to use for FIB lookups. For devices
  73  * enslaved to an L3 master device FIB lookups are based on the
  74  * master index
  75  */
  76 static inline int l3mdev_fib_oif_rcu(struct net_device *dev)
  77 {
  78         return l3mdev_master_ifindex_rcu(dev) ? : dev->ifindex;
  79 }
  80
  81 static inline int l3mdev_fib_oif(struct net_device *dev)
  82 {
  83         int oif;
  84
  85         rcu_read_lock();
  86         oif = l3mdev_fib_oif_rcu(dev);
  87         rcu_read_unlock();
  88
  89         return oif;
  90 }
  91
  92 u32 l3mdev_fib_table_rcu(const struct net_device *dev);
  93 u32 l3mdev_fib_table_by_index(struct net *net, int ifindex);
  94 static inline u32 l3mdev_fib_table(const struct net_device *dev)
  95 {
  96         u32 tb_id;
  97
  98         rcu_read_lock();
  99         tb_id = l3mdev_fib_table_rcu(dev);
 100         rcu_read_unlock();
 101
 102         return tb_id;
 103 }
 104
 105 static inline struct rtable *l3mdev_get_rtable(const struct net_device *dev,
 106                                                const struct flowi4 *fl4)
 107 {
 108         if (netif_is_l3_master(dev) && dev->l3mdev_ops->l3mdev_get_rtable)
 109                 return dev->l3mdev_ops->l3mdev_get_rtable(dev, fl4);
 110
 111         return NULL;
 112 }
 113
 114 static inline bool netif_index_is_l3_master(struct net *net, int ifindex)
 115 {
 116         struct net_device *dev;
 117         bool rc = false;
 118
 119         if (ifindex == 0)
 120                 return false;
 121
 122         rcu_read_lock();
 123
 124         dev = dev_get_by_index_rcu(net, ifindex);
 125         if (dev)
 126                 rc = netif_is_l3_master(dev);
 127
 128         rcu_read_unlock();
 129
 130         return rc;
 131 }
 132
 133 static inline int l3mdev_get_saddr(struct net *net, int ifindex,
 134                                    struct flowi4 *fl4)
 135 {
 136         struct net_device *dev;
 137         int rc = 0;
 138
 139         if (ifindex) {
 140
 141                 rcu_read_lock();
 142
 143                 dev = dev_get_by_index_rcu(net, ifindex);
 144                 if (dev && netif_is_l3_master(dev) &&
 145                     dev->l3mdev_ops->l3mdev_get_saddr) {
 146                         rc = dev->l3mdev_ops->l3mdev_get_saddr(dev, fl4);
 147                 }
 148
 149                 rcu_read_unlock();
 150         }
 151
 152         return rc;
 153 }
 154
 155 static inline struct dst_entry *l3mdev_get_rt6_dst(const struct net_device *dev,
 156                                                    const struct flowi6 *fl6)
 157 {
 158         if (netif_is_l3_master(dev) && dev->l3mdev_ops->l3mdev_get_rt6_dst)
 159                 return dev->l3mdev_ops->l3mdev_get_rt6_dst(dev, fl6);
 160
 161         return NULL;
 162 }
 163
 164 static inline
 165 struct dst_entry *l3mdev_rt6_dst_by_oif(struct net *net,
 166                                         const struct flowi6 *fl6)
 167 {
 168         struct dst_entry *dst = NULL;
 169         struct net_device *dev;
 170
 171         dev = dev_get_by_index(net, fl6->flowi6_oif);
 172         if (dev) {
 173                 dst = l3mdev_get_rt6_dst(dev, fl6);
 174                 dev_put(dev);
 175         }
 176
 177         return dst;
 178 }
 179
 180 #else
 181
 182 static inline int l3mdev_master_ifindex_rcu(struct net_device *dev)
 183 {
 184         return 0;
 185 }
 186 static inline int l3mdev_master_ifindex(struct net_device *dev)
 187 {
 188         return 0;
 189 }
 190
 191 static inline int l3mdev_master_ifindex_by_index(struct net *net, int ifindex)
 192 {
 193         return 0;
 194 }
 195
 196 static inline int l3mdev_fib_oif_rcu(struct net_device *dev)
 197 {
 198         return dev ? dev->ifindex : 0;
 199 }
 200 static inline int l3mdev_fib_oif(struct net_device *dev)
 201 {
 202         return dev ? dev->ifindex : 0;
 203 }
 204
 205 static inline u32 l3mdev_fib_table_rcu(const struct net_device *dev)
 206 {
 207         return 0;
 208 }
 209 static inline u32 l3mdev_fib_table(const struct net_device *dev)
 210 {
 211         return 0;
 212 }
 213 static inline u32 l3mdev_fib_table_by_index(struct net *net, int ifindex)
 214 {
 215         return 0;
 216 }
 217
 218 static inline struct rtable *l3mdev_get_rtable(const struct net_device *dev,
 219                                                const struct flowi4 *fl4)
 220 {
 221         return NULL;
 222 }
 223
 224 static inline bool netif_index_is_l3_master(struct net *net, int ifindex)
 225 {
 226         return false;
 227 }
 228
 229 static inline int l3mdev_get_saddr(struct net *net, int ifindex,
 230                                    struct flowi4 *fl4)
 231 {
 232         return 0;
 233 }
 234
 235 static inline
 236 struct dst_entry *l3mdev_get_rt6_dst(const struct net_device *dev,
 237                                      const struct flowi6 *fl6)
 238 {
 239         return NULL;
 240 }
 241 static inline
 242 struct dst_entry *l3mdev_rt6_dst_by_oif(struct net *net,
 243                                         const struct flowi6 *fl6)
 244 {
 245         return NULL;
 246 }
 247 #endif
 248
 249 #endif /* _NET_L3MDEV_H_ */