xref: /linux-6.15/include/linux/rtnetlink.h (revision e17fb91c)
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 #ifdef CONFIG_PROVE_LOCKING
55 extern bool lockdep_rtnl_is_held(void);
56 #else
57 static inline bool lockdep_rtnl_is_held(void)
58 {
59 	return true;
60 }
61 #endif /* #ifdef CONFIG_PROVE_LOCKING */
62 
63 /**
64  * rcu_dereference_rtnl - rcu_dereference with debug checking
65  * @p: The pointer to read, prior to dereferencing
66  *
67  * Do an rcu_dereference(p), but check caller either holds rcu_read_lock()
68  * or RTNL. Note : Please prefer rtnl_dereference() or rcu_dereference()
69  */
70 #define rcu_dereference_rtnl(p)					\
71 	rcu_dereference_check(p, lockdep_rtnl_is_held())
72 
73 /**
74  * rtnl_dereference - fetch RCU pointer when updates are prevented by RTNL
75  * @p: The pointer to read, prior to dereferencing
76  *
77  * Return the value of the specified RCU-protected pointer, but omit
78  * the READ_ONCE(), because caller holds RTNL.
79  */
80 #define rtnl_dereference(p)					\
81 	rcu_dereference_protected(p, lockdep_rtnl_is_held())
82 
83 /**
84  * rcu_replace_pointer_rtnl - replace an RCU pointer under rtnl_lock, returning
85  * its old value
86  * @rp: RCU pointer, whose value is returned
87  * @p: regular pointer
88  *
89  * Perform a replacement under rtnl_lock, where @rp is an RCU-annotated
90  * pointer. The old value of @rp is returned, and @rp is set to @p
91  */
92 #define rcu_replace_pointer_rtnl(rp, p)			\
93 	rcu_replace_pointer(rp, p, lockdep_rtnl_is_held())
94 
95 static inline struct netdev_queue *dev_ingress_queue(struct net_device *dev)
96 {
97 	return rtnl_dereference(dev->ingress_queue);
98 }
99 
100 static inline struct netdev_queue *dev_ingress_queue_rcu(struct net_device *dev)
101 {
102 	return rcu_dereference(dev->ingress_queue);
103 }
104 
105 struct netdev_queue *dev_ingress_queue_create(struct net_device *dev);
106 
107 #ifdef CONFIG_NET_INGRESS
108 void net_inc_ingress_queue(void);
109 void net_dec_ingress_queue(void);
110 #endif
111 
112 #ifdef CONFIG_NET_EGRESS
113 void net_inc_egress_queue(void);
114 void net_dec_egress_queue(void);
115 void netdev_xmit_skip_txqueue(bool skip);
116 #endif
117 
118 void rtnetlink_init(void);
119 void __rtnl_unlock(void);
120 void rtnl_kfree_skbs(struct sk_buff *head, struct sk_buff *tail);
121 
122 #define ASSERT_RTNL() \
123 	WARN_ONCE(!rtnl_is_locked(), \
124 		  "RTNL: assertion failed at %s (%d)\n", __FILE__,  __LINE__)
125 
126 extern int ndo_dflt_fdb_dump(struct sk_buff *skb,
127 			     struct netlink_callback *cb,
128 			     struct net_device *dev,
129 			     struct net_device *filter_dev,
130 			     int *idx);
131 extern int ndo_dflt_fdb_add(struct ndmsg *ndm,
132 			    struct nlattr *tb[],
133 			    struct net_device *dev,
134 			    const unsigned char *addr,
135 			    u16 vid,
136 			    u16 flags);
137 extern int ndo_dflt_fdb_del(struct ndmsg *ndm,
138 			    struct nlattr *tb[],
139 			    struct net_device *dev,
140 			    const unsigned char *addr,
141 			    u16 vid);
142 
143 extern int ndo_dflt_bridge_getlink(struct sk_buff *skb, u32 pid, u32 seq,
144 				   struct net_device *dev, u16 mode,
145 				   u32 flags, u32 mask, int nlflags,
146 				   u32 filter_mask,
147 				   int (*vlan_fill)(struct sk_buff *skb,
148 						    struct net_device *dev,
149 						    u32 filter_mask));
150 
151 extern void rtnl_offload_xstats_notify(struct net_device *dev);
152 
153 static inline int rtnl_has_listeners(const struct net *net, u32 group)
154 {
155 	struct sock *rtnl = net->rtnl;
156 
157 	return netlink_has_listeners(rtnl, group);
158 }
159 
160 /**
161  * rtnl_notify_needed - check if notification is needed
162  * @net: Pointer to the net namespace
163  * @nlflags: netlink ingress message flags
164  * @group: rtnl group
165  *
166  * Based on the ingress message flags and rtnl group, returns true
167  * if a notification is needed, false otherwise.
168  */
169 static inline bool
170 rtnl_notify_needed(const struct net *net, u16 nlflags, u32 group)
171 {
172 	return (nlflags & NLM_F_ECHO) || rtnl_has_listeners(net, group);
173 }
174 
175 void netdev_set_operstate(struct net_device *dev, int newstate);
176 
177 #endif	/* __LINUX_RTNETLINK_H */
178