summaryrefslogtreecommitdiffstats
path: root/include/net/net_namespace.h
blob: 90802a668c235f20f9b40f63db4b001d7123de3b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
/*
 * Operations on the network namespace
 */
#ifndef __NET_NET_NAMESPACE_H
#define __NET_NET_NAMESPACE_H

#include <asm/atomic.h>
#include <linux/workqueue.h>
#include <linux/list.h>

struct proc_dir_entry;
struct net_device;
struct sock;
struct net {
	atomic_t		count;		/* To decided when the network
						 *  namespace should be freed.
						 */
	atomic_t		use_count;	/* To track references we
						 * destroy on demand
						 */
	struct list_head	list;		/* list of network namespaces */
	struct work_struct	work;		/* work struct for freeing */

	struct proc_dir_entry 	*proc_net;
	struct proc_dir_entry 	*proc_net_stat;
	struct proc_dir_entry 	*proc_net_root;

	struct net_device       *loopback_dev;          /* The loopback */

	struct list_head 	dev_base_head;
	struct hlist_head 	*dev_name_head;
	struct hlist_head	*dev_index_head;

	struct sock 		*rtnl;			/* rtnetlink socket */
};

#ifdef CONFIG_NET
/* Init's network namespace */
extern struct net init_net;
#define INIT_NET_NS(net_ns) .net_ns = &init_net,
#else
#define INIT_NET_NS(net_ns)
#endif

extern struct list_head net_namespace_list;

#ifdef CONFIG_NET
extern struct net *copy_net_ns(unsigned long flags, struct net *net_ns);
#else
static inline struct net *copy_net_ns(unsigned long flags, struct net *net_ns)
{
	/* There is nothing to copy so this is a noop */
	return net_ns;
}
#endif

#ifdef CONFIG_NET_NS
extern void __put_net(struct net *net);

static inline struct net *get_net(struct net *net)
{
	atomic_inc(&net->count);
	return net;
}

static inline struct net *maybe_get_net(struct net *net)
{
	/* Used when we know struct net exists but we
	 * aren't guaranteed a previous reference count
	 * exists.  If the reference count is zero this
	 * function fails and returns NULL.
	 */
	if (!atomic_inc_not_zero(&net->count))
		net = NULL;
	return net;
}

static inline void put_net(struct net *net)
{
	if (atomic_dec_and_test(&net->count))
		__put_net(net);
}

static inline struct net *hold_net(struct net *net)
{
	atomic_inc(&net->use_count);
	return net;
}

static inline void release_net(struct net *net)
{
	atomic_dec(&net->use_count);
}
#else
static inline struct net *get_net(struct net *net)
{
	return net;
}

static inline void put_net(struct net *net)
{
}

static inline struct net *hold_net(struct net *net)
{
	return net;
}

static inline void release_net(struct net *net)
{
}

static inline struct net *maybe_get_net(struct net *net)
{
	return net;
}
#endif

#define for_each_net(VAR)				\
	list_for_each_entry(VAR, &net_namespace_list, list)

#ifdef CONFIG_NET_NS
#define __net_init
#define __net_exit
#define __net_initdata
#else
#define __net_init	__init
#define __net_exit	__exit_refok
#define __net_initdata	__initdata
#endif

struct pernet_operations {
	struct list_head list;
	int (*init)(struct net *net);
	void (*exit)(struct net *net);
};

extern int register_pernet_subsys(struct pernet_operations *);
extern void unregister_pernet_subsys(struct pernet_operations *);
extern int register_pernet_device(struct pernet_operations *);
extern void unregister_pernet_device(struct pernet_operations *);

#endif /* __NET_NET_NAMESPACE_H */
OpenPOWER on IntegriCloud