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
 12extern int rtnetlink_send(struct sk_buff *skb, struct net *net, u32 pid, u32 group, int echo);
 13
 14static 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
 20extern int rtnl_unicast(struct sk_buff *skb, struct net *net, u32 pid);
 21extern void rtnl_notify(struct sk_buff *skb, struct net *net, u32 pid,
 22			u32 group, const struct nlmsghdr *nlh, gfp_t flags);
 23extern void rtnl_set_sk_err(struct net *net, u32 group, int error);
 24extern int rtnetlink_put_metrics(struct sk_buff *skb, u32 *metrics);
 25extern int rtnl_put_cacheinfo(struct sk_buff *skb, struct dst_entry *dst,
 26			      u32 id, long expires, u32 error);
 27
 28void rtmsg_ifinfo(int type, struct net_device *dev, unsigned int change, gfp_t flags,
 29		  u32 portid, const struct nlmsghdr *nlh);
 30void rtmsg_ifinfo_newnet(int type, struct net_device *dev, unsigned int change,
 31			 gfp_t flags, int *new_nsid, int new_ifindex);
 32struct 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);
 37void 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  */
 42extern void rtnl_lock(void);
 43extern void rtnl_unlock(void);
 44extern int rtnl_trylock(void);
 45extern int rtnl_is_locked(void);
 46extern int rtnl_lock_interruptible(void);
 47extern int rtnl_lock_killable(void);
 48extern bool refcount_dec_and_rtnl_lock(refcount_t *r);
 49
 50extern wait_queue_head_t netdev_unregistering_wq;
 51extern atomic_t dev_unreg_count;
 52extern struct rw_semaphore pernet_ops_rwsem;
 53extern struct rw_semaphore net_rwsem;
 54
 55#define ASSERT_RTNL() \
 56	WARN_ONCE(!rtnl_is_locked(), \
 57		  "RTNL: assertion failed at %s (%d)\n", __FILE__,  __LINE__)
 58
 59#ifdef CONFIG_PROVE_LOCKING
 60extern bool lockdep_rtnl_is_held(void);
 61#else
 62static inline bool lockdep_rtnl_is_held(void)
 63{
 64	return true;
 65}
 66#endif /* #ifdef CONFIG_PROVE_LOCKING */
 67
 68/**
 69 * rcu_dereference_rtnl - rcu_dereference with debug checking
 70 * @p: The pointer to read, prior to dereferencing
 71 *
 72 * Do an rcu_dereference(p), but check caller either holds rcu_read_lock()
 73 * or RTNL. Note : Please prefer rtnl_dereference() or rcu_dereference()
 74 */
 75#define rcu_dereference_rtnl(p)					\
 76	rcu_dereference_check(p, lockdep_rtnl_is_held())
 77
 78/**
 79 * rtnl_dereference - fetch RCU pointer when updates are prevented by RTNL
 80 * @p: The pointer to read, prior to dereferencing
 81 *
 82 * Return: the value of the specified RCU-protected pointer, but omit
 83 * the READ_ONCE(), because caller holds RTNL.
 84 */
 85#define rtnl_dereference(p)					\
 86	rcu_dereference_protected(p, lockdep_rtnl_is_held())
 87
 88/**
 89 * rcu_replace_pointer_rtnl - replace an RCU pointer under rtnl_lock, returning
 90 * its old value
 91 * @rp: RCU pointer, whose value is returned
 92 * @p: regular pointer
 93 *
 94 * Perform a replacement under rtnl_lock, where @rp is an RCU-annotated
 95 * pointer. The old value of @rp is returned, and @rp is set to @p
 96 */
 97#define rcu_replace_pointer_rtnl(rp, p)			\
 98	rcu_replace_pointer(rp, p, lockdep_rtnl_is_held())
 99
100#ifdef CONFIG_DEBUG_NET_SMALL_RTNL
101void __rtnl_net_lock(struct net *net);
102void __rtnl_net_unlock(struct net *net);
103void rtnl_net_lock(struct net *net);
104void rtnl_net_unlock(struct net *net);
105int rtnl_net_trylock(struct net *net);
106int rtnl_net_lock_killable(struct net *net);
107int rtnl_net_lock_cmp_fn(const struct lockdep_map *a, const struct lockdep_map *b);
108
109bool rtnl_net_is_locked(struct net *net);
110
111#define ASSERT_RTNL_NET(net)						\
112	WARN_ONCE(!rtnl_net_is_locked(net),				\
113		  "RTNL_NET: assertion failed at %s (%d)\n",		\
114		  __FILE__,  __LINE__)
115
116bool lockdep_rtnl_net_is_held(struct net *net);
117
118#define rcu_dereference_rtnl_net(net, p)				\
119	rcu_dereference_check(p, lockdep_rtnl_net_is_held(net))
120#define rtnl_net_dereference(net, p)					\
121	rcu_dereference_protected(p, lockdep_rtnl_net_is_held(net))
122#define rcu_replace_pointer_rtnl_net(net, rp, p)			\
123	rcu_replace_pointer(rp, p, lockdep_rtnl_net_is_held(net))
124#else
125static inline void __rtnl_net_lock(struct net *net) {}
126static inline void __rtnl_net_unlock(struct net *net) {}
127
128static inline void rtnl_net_lock(struct net *net)
129{
130	rtnl_lock();
131}
132
133static inline void rtnl_net_unlock(struct net *net)
134{
135	rtnl_unlock();
136}
137
138static inline int rtnl_net_trylock(struct net *net)
139{
140	return rtnl_trylock();
141}
142
143static inline int rtnl_net_lock_killable(struct net *net)
144{
145	return rtnl_lock_killable();
146}
147
148static inline void ASSERT_RTNL_NET(struct net *net)
149{
150	ASSERT_RTNL();
151}
152
153#define rcu_dereference_rtnl_net(net, p)		\
154	rcu_dereference_rtnl(p)
155#define rtnl_net_dereference(net, p)			\
156	rtnl_dereference(p)
157#define rcu_replace_pointer_rtnl_net(net, rp, p)	\
158	rcu_replace_pointer_rtnl(rp, p)
159#endif
160
161static inline struct netdev_queue *dev_ingress_queue(struct net_device *dev)
162{
163	return rtnl_dereference(dev->ingress_queue);
164}
165
166static inline struct netdev_queue *dev_ingress_queue_rcu(struct net_device *dev)
167{
168	return rcu_dereference(dev->ingress_queue);
169}
170
171struct netdev_queue *dev_ingress_queue_create(struct net_device *dev);
172
173#ifdef CONFIG_NET_INGRESS
174void net_inc_ingress_queue(void);
175void net_dec_ingress_queue(void);
176#endif
177
178#ifdef CONFIG_NET_EGRESS
179void net_inc_egress_queue(void);
180void net_dec_egress_queue(void);
181void netdev_xmit_skip_txqueue(bool skip);
182#endif
183
184void rtnetlink_init(void);
185void __rtnl_unlock(void);
186void rtnl_kfree_skbs(struct sk_buff *head, struct sk_buff *tail);
187
188/* Shared by rtnl_fdb_dump() and various ndo_fdb_dump() helpers. */
189struct ndo_fdb_dump_context {
190	unsigned long ifindex;
191	unsigned long fdb_idx;
192};
193
194extern int ndo_dflt_fdb_dump(struct sk_buff *skb,
195			     struct netlink_callback *cb,
196			     struct net_device *dev,
197			     struct net_device *filter_dev,
198			     int *idx);
199extern int ndo_dflt_fdb_add(struct ndmsg *ndm,
200			    struct nlattr *tb[],
201			    struct net_device *dev,
202			    const unsigned char *addr,
203			    u16 vid,
204			    u16 flags);
205extern int ndo_dflt_fdb_del(struct ndmsg *ndm,
206			    struct nlattr *tb[],
207			    struct net_device *dev,
208			    const unsigned char *addr,
209			    u16 vid);
210
211extern int ndo_dflt_bridge_getlink(struct sk_buff *skb, u32 pid, u32 seq,
212				   struct net_device *dev, u16 mode,
213				   u32 flags, u32 mask, int nlflags,
214				   u32 filter_mask,
215				   int (*vlan_fill)(struct sk_buff *skb,
216						    struct net_device *dev,
217						    u32 filter_mask));
218
219extern void rtnl_offload_xstats_notify(struct net_device *dev);
220
221static inline int rtnl_has_listeners(const struct net *net, u32 group)
222{
223	struct sock *rtnl = net->rtnl;
224
225	return netlink_has_listeners(rtnl, group);
226}
227
228/**
229 * rtnl_notify_needed - check if notification is needed
230 * @net: Pointer to the net namespace
231 * @nlflags: netlink ingress message flags
232 * @group: rtnl group
233 *
234 * Based on the ingress message flags and rtnl group, returns true
235 * if a notification is needed, false otherwise.
236 */
237static inline bool
238rtnl_notify_needed(const struct net *net, u16 nlflags, u32 group)
239{
240	return (nlflags & NLM_F_ECHO) || rtnl_has_listeners(net, group);
241}
242
243void netif_set_operstate(struct net_device *dev, int newstate);
244
245#endif	/* __LINUX_RTNETLINK_H */