1#ifndef _AF_NETLINK_H
2#define _AF_NETLINK_H
3
4#include <linux/rhashtable.h>
5#include <linux/atomic.h>
6#include <net/sock.h>
7
8#define NLGRPSZ(x)	(ALIGN(x, sizeof(unsigned long) * 8) / 8)
9#define NLGRPLONGS(x)	(NLGRPSZ(x)/sizeof(unsigned long))
10
11struct netlink_ring {
12	void			**pg_vec;
13	unsigned int		head;
14	unsigned int		frames_per_block;
15	unsigned int		frame_size;
16	unsigned int		frame_max;
17
18	unsigned int		pg_vec_order;
19	unsigned int		pg_vec_pages;
20	unsigned int		pg_vec_len;
21
22	atomic_t		pending;
23};
24
25struct netlink_sock {
26	/* struct sock has to be the first member of netlink_sock */
27	struct sock		sk;
28	u32			portid;
29	u32			dst_portid;
30	u32			dst_group;
31	u32			flags;
32	u32			subscriptions;
33	u32			ngroups;
34	unsigned long		*groups;
35	unsigned long		state;
36	size_t			max_recvmsg_len;
37	wait_queue_head_t	wait;
38	bool			bound;
39	bool			cb_running;
40	struct netlink_callback	cb;
41	struct mutex		*cb_mutex;
42	struct mutex		cb_def_mutex;
43	void			(*netlink_rcv)(struct sk_buff *skb);
44	int			(*netlink_bind)(struct net *net, int group);
45	void			(*netlink_unbind)(struct net *net, int group);
46	struct module		*module;
47#ifdef CONFIG_NETLINK_MMAP
48	struct mutex		pg_vec_lock;
49	struct netlink_ring	rx_ring;
50	struct netlink_ring	tx_ring;
51	atomic_t		mapped;
52#endif /* CONFIG_NETLINK_MMAP */
53
54	struct rhash_head	node;
55	struct rcu_head		rcu;
56};
57
58static inline struct netlink_sock *nlk_sk(struct sock *sk)
59{
60	return container_of(sk, struct netlink_sock, sk);
61}
62
63static inline bool netlink_skb_is_mmaped(const struct sk_buff *skb)
64{
65#ifdef CONFIG_NETLINK_MMAP
66	return NETLINK_CB(skb).flags & NETLINK_SKB_MMAPED;
67#else
68	return false;
69#endif /* CONFIG_NETLINK_MMAP */
70}
71
72struct netlink_table {
73	struct rhashtable	hash;
74	struct hlist_head	mc_list;
75	struct listeners __rcu	*listeners;
76	unsigned int		flags;
77	unsigned int		groups;
78	struct mutex		*cb_mutex;
79	struct module		*module;
80	int			(*bind)(struct net *net, int group);
81	void			(*unbind)(struct net *net, int group);
82	bool			(*compare)(struct net *net, struct sock *sock);
83	int			registered;
84};
85
86extern struct netlink_table *nl_table;
87extern rwlock_t nl_table_lock;
88
89#endif
90