include/linux/rtnetlink.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef __LINUX_RTNETLINK_H
   3 #define __LINUX_RTNETLINK_H
   4
   5
   6 #include <linux/mutex.h>
   7 #include <linux/netdevice.h>
   8 #include <linux/wait.h>
   9 #include <linux/refcount.h>
  10 #include <uapi/linux/rtnetlink.h>
  11
  12 extern int rtnetlink_send(struct sk_buff *skb, struct net *net, u32 pid, u32 group, int echo);
  13
  14 static inline int rtnetlink_maybe_send(struct sk_buff *skb, struct net *net,
  15                                        u32 pid, u32 group, int echo)
  16 {
  17         return !skb ? 0 : rtnetlink_send(skb, net, pid, group, echo);
  18 }
  19
  20 extern int rtnl_unicast(struct sk_buff *skb, struct net *net, u32 pid);
  21 extern void rtnl_notify(struct sk_buff *skb, struct net *net, u32 pid,
  22                         u32 group, const struct nlmsghdr *nlh, gfp_t flags);
  23 extern void rtnl_set_sk_err(struct net *net, u32 group, int error);
  24 extern int rtnetlink_put_metrics(struct sk_buff *skb, u32 *metrics);
  25 extern int rtnl_put_cacheinfo(struct sk_buff *skb, struct dst_entry *dst,
  26                               u32 id, long expires, u32 error);
  27
  28 void rtmsg_ifinfo(int type, struct net_device *dev, unsigned int change, gfp_t flags,
  29                   u32 portid, const struct nlmsghdr *nlh);
  30 void rtmsg_ifinfo_newnet(int type, struct net_device *dev, unsigned int change,
  31                          gfp_t flags, int *new_nsid, int new_ifindex);
  32 struct sk_buff *rtmsg_ifinfo_build_skb(int type, struct net_device *dev,
  33                                        unsigned change, u32 event,
  34                                        gfp_t flags, int *new_nsid,
  35                                        int new_ifindex, u32 portid,
  36                                        const struct nlmsghdr *nlh);
  37 void rtmsg_ifinfo_send(struct sk_buff *skb, struct net_device *dev,
  38                        gfp_t flags, u32 portid, const struct nlmsghdr *nlh);
  39
  40
  41 /* RTNL is used as a global lock for all changes to network configuration  */
  42 extern void rtnl_lock(void);
  43 extern void rtnl_unlock(void);
  44 extern int rtnl_trylock(void);
  45 extern int rtnl_is_locked(void);
  46 extern int rtnl_lock_killable(void);
  47 extern bool refcount_dec_and_rtnl_lock(refcount_t *r);
  48
  49 extern wait_queue_head_t netdev_unregistering_wq;
  50 extern atomic_t dev_unreg_count;
  51 extern struct rw_semaphore pernet_ops_rwsem;
  52 extern struct rw_semaphore net_rwsem;
  53
  54 #define ASSERT_RTNL() \
  55         WARN_ONCE(!rtnl_is_locked(), \
  56                   "RTNL: assertion failed at %s (%d)\n", __FILE__,  __LINE__)
  57
  58 #ifdef CONFIG_PROVE_LOCKING
  59 extern bool lockdep_rtnl_is_held(void);
  60 #else
  61 static inline bool lockdep_rtnl_is_held(void)
  62 {
  63         return true;
  64 }
  65 #endif /* #ifdef CONFIG_PROVE_LOCKING */
  66
  67 /**
  68  * rcu_dereference_rtnl - rcu_dereference with debug checking
  69  * @p: The pointer to read, prior to dereferencing
  70  *
  71  * Do an rcu_dereference(p), but check caller either holds rcu_read_lock()
  72  * or RTNL. Note : Please prefer rtnl_dereference() or rcu_dereference()
  73  */
  74 #define rcu_dereference_rtnl(p)                                 \
  75         rcu_dereference_check(p, lockdep_rtnl_is_held())
  76
  77 /**
  78  * rtnl_dereference - fetch RCU pointer when updates are prevented by RTNL
  79  * @p: The pointer to read, prior to dereferencing
  80  *
  81  * Return the value of the specified RCU-protected pointer, but omit
  82  * the READ_ONCE(), because caller holds RTNL.
  83  */
  84 #define rtnl_dereference(p)                                     \
  85         rcu_dereference_protected(p, lockdep_rtnl_is_held())
  86
  87 /**
  88  * rcu_replace_pointer_rtnl - replace an RCU pointer under rtnl_lock, returning
  89  * its old value
  90  * @rp: RCU pointer, whose value is returned
  91  * @p: regular pointer
  92  *
  93  * Perform a replacement under rtnl_lock, where @rp is an RCU-annotated
  94  * pointer. The old value of @rp is returned, and @rp is set to @p
  95  */
  96 #define rcu_replace_pointer_rtnl(rp, p)                 \
  97         rcu_replace_pointer(rp, p, lockdep_rtnl_is_held())
  98
  99 #ifdef CONFIG_DEBUG_NET_SMALL_RTNL
 100 void __rtnl_net_lock(struct net *net);
 101 void __rtnl_net_unlock(struct net *net);
 102 void rtnl_net_lock(struct net *net);
 103 void rtnl_net_unlock(struct net *net);
 104 int rtnl_net_trylock(struct net *net);
 105 int rtnl_net_lock_cmp_fn(const struct lockdep_map *a, const struct lockdep_map *b);
 106
 107 bool rtnl_net_is_locked(struct net *net);
 108
 109 #define ASSERT_RTNL_NET(net)                                            \
 110         WARN_ONCE(!rtnl_net_is_locked(net),                             \
 111                   "RTNL_NET: assertion failed at %s (%d)\n",            \
 112                   __FILE__,  __LINE__)
 113
 114 bool lockdep_rtnl_net_is_held(struct net *net);
 115
 116 #define rcu_dereference_rtnl_net(net, p)                                \
 117         rcu_dereference_check(p, lockdep_rtnl_net_is_held(net))
 118 #define rtnl_net_dereference(net, p)                                    \
 119         rcu_dereference_protected(p, lockdep_rtnl_net_is_held(net))
 120 #define rcu_replace_pointer_rtnl_net(net, rp, p)                        \
 121         rcu_replace_pointer(rp, p, lockdep_rtnl_net_is_held(net))
 122 #else
 123 static inline void __rtnl_net_lock(struct net *net) {}
 124 static inline void __rtnl_net_unlock(struct net *net) {}
 125
 126 static inline void rtnl_net_lock(struct net *net)
 127 {
 128         rtnl_lock();
 129 }
 130
 131 static inline void rtnl_net_unlock(struct net *net)
 132 {
 133         rtnl_unlock();
 134 }
 135
 136 static inline int rtnl_net_trylock(struct net *net)
 137 {
 138         return rtnl_trylock();
 139 }
 140
 141 static inline void ASSERT_RTNL_NET(struct net *net)
 142 {
 143         ASSERT_RTNL();
 144 }
 145
 146 #define rcu_dereference_rtnl_net(net, p)                \
 147         rcu_dereference_rtnl(p)
 148 #define rtnl_net_dereference(net, p)                    \
 149         rtnl_dereference(p)
 150 #define rcu_replace_pointer_rtnl_net(net, rp, p)        \
 151         rcu_replace_pointer_rtnl(rp, p)
 152 #endif
 153
 154 static inline struct netdev_queue *dev_ingress_queue(struct net_device *dev)
 155 {
 156         return rtnl_dereference(dev->ingress_queue);
 157 }
 158
 159 static inline struct netdev_queue *dev_ingress_queue_rcu(struct net_device *dev)
 160 {
 161         return rcu_dereference(dev->ingress_queue);
 162 }
 163
 164 struct netdev_queue *dev_ingress_queue_create(struct net_device *dev);
 165
 166 #ifdef CONFIG_NET_INGRESS
 167 void net_inc_ingress_queue(void);
 168 void net_dec_ingress_queue(void);
 169 #endif
 170
 171 #ifdef CONFIG_NET_EGRESS
 172 void net_inc_egress_queue(void);
 173 void net_dec_egress_queue(void);
 174 void netdev_xmit_skip_txqueue(bool skip);
 175 #endif
 176
 177 void rtnetlink_init(void);
 178 void __rtnl_unlock(void);
 179 void rtnl_kfree_skbs(struct sk_buff *head, struct sk_buff *tail);
 180
 181 extern int ndo_dflt_fdb_dump(struct sk_buff *skb,
 182                              struct netlink_callback *cb,
 183                              struct net_device *dev,
 184                              struct net_device *filter_dev,
 185                              int *idx);
 186 extern int ndo_dflt_fdb_add(struct ndmsg *ndm,
 187                             struct nlattr *tb[],
 188                             struct net_device *dev,
 189                             const unsigned char *addr,
 190                             u16 vid,
 191                             u16 flags);
 192 extern int ndo_dflt_fdb_del(struct ndmsg *ndm,
 193                             struct nlattr *tb[],
 194                             struct net_device *dev,
 195                             const unsigned char *addr,
 196                             u16 vid);
 197
 198 extern int ndo_dflt_bridge_getlink(struct sk_buff *skb, u32 pid, u32 seq,
 199                                    struct net_device *dev, u16 mode,
 200                                    u32 flags, u32 mask, int nlflags,
 201                                    u32 filter_mask,
 202                                    int (*vlan_fill)(struct sk_buff *skb,
 203                                                     struct net_device *dev,
 204                                                     u32 filter_mask));
 205
 206 extern void rtnl_offload_xstats_notify(struct net_device *dev);
 207
 208 static inline int rtnl_has_listeners(const struct net *net, u32 group)
 209 {
 210         struct sock *rtnl = net->rtnl;
 211
 212         return netlink_has_listeners(rtnl, group);
 213 }
 214
 215 /**
 216  * rtnl_notify_needed - check if notification is needed
 217  * @net: Pointer to the net namespace
 218  * @nlflags: netlink ingress message flags
 219  * @group: rtnl group
 220  *
 221  * Based on the ingress message flags and rtnl group, returns true
 222  * if a notification is needed, false otherwise.
 223  */
 224 static inline bool
 225 rtnl_notify_needed(const struct net *net, u16 nlflags, u32 group)
 226 {
 227         return (nlflags & NLM_F_ECHO) || rtnl_has_listeners(net, group);
 228 }
 229
 230 void netdev_set_operstate(struct net_device *dev, int newstate);
 231
 232 #endif  /* __LINUX_RTNETLINK_H */