xref: /linux/net/netlink/af_netlink.h (revision 3932b9ca55b0be314a36d3e84faff3e823c081f5)
1 #ifndef _AF_NETLINK_H
2 #define _AF_NETLINK_H
3 
4 #include <linux/rhashtable.h>
5 #include <net/sock.h>
6 
7 #define NLGRPSZ(x)	(ALIGN(x, sizeof(unsigned long) * 8) / 8)
8 #define NLGRPLONGS(x)	(NLGRPSZ(x)/sizeof(unsigned long))
9 
10 struct netlink_ring {
11 	void			**pg_vec;
12 	unsigned int		head;
13 	unsigned int		frames_per_block;
14 	unsigned int		frame_size;
15 	unsigned int		frame_max;
16 
17 	unsigned int		pg_vec_order;
18 	unsigned int		pg_vec_pages;
19 	unsigned int		pg_vec_len;
20 
21 	atomic_t		pending;
22 };
23 
24 struct netlink_sock {
25 	/* struct sock has to be the first member of netlink_sock */
26 	struct sock		sk;
27 	u32			portid;
28 	u32			dst_portid;
29 	u32			dst_group;
30 	u32			flags;
31 	u32			subscriptions;
32 	u32			ngroups;
33 	unsigned long		*groups;
34 	unsigned long		state;
35 	size_t			max_recvmsg_len;
36 	wait_queue_head_t	wait;
37 	bool			cb_running;
38 	struct netlink_callback	cb;
39 	struct mutex		*cb_mutex;
40 	struct mutex		cb_def_mutex;
41 	void			(*netlink_rcv)(struct sk_buff *skb);
42 	int			(*netlink_bind)(int group);
43 	void			(*netlink_unbind)(int group);
44 	struct module		*module;
45 #ifdef CONFIG_NETLINK_MMAP
46 	struct mutex		pg_vec_lock;
47 	struct netlink_ring	rx_ring;
48 	struct netlink_ring	tx_ring;
49 	atomic_t		mapped;
50 #endif /* CONFIG_NETLINK_MMAP */
51 
52 	struct rhash_head	node;
53 };
54 
55 static inline struct netlink_sock *nlk_sk(struct sock *sk)
56 {
57 	return container_of(sk, struct netlink_sock, sk);
58 }
59 
60 struct netlink_table {
61 	struct rhashtable	hash;
62 	struct hlist_head	mc_list;
63 	struct listeners __rcu	*listeners;
64 	unsigned int		flags;
65 	unsigned int		groups;
66 	struct mutex		*cb_mutex;
67 	struct module		*module;
68 	int			(*bind)(int group);
69 	void			(*unbind)(int group);
70 	bool			(*compare)(struct net *net, struct sock *sock);
71 	int			registered;
72 };
73 
74 extern struct netlink_table *nl_table;
75 extern rwlock_t nl_table_lock;
76 extern struct mutex nl_sk_hash_lock;
77 
78 #endif
79