xref: /openbmc/linux/include/net/net_namespace.h (revision 643d1f7f)
1 /*
2  * Operations on the network namespace
3  */
4 #ifndef __NET_NET_NAMESPACE_H
5 #define __NET_NET_NAMESPACE_H
6 
7 #include <asm/atomic.h>
8 #include <linux/workqueue.h>
9 #include <linux/list.h>
10 
11 #include <net/netns/unix.h>
12 #include <net/netns/packet.h>
13 #include <net/netns/ipv4.h>
14 #include <net/netns/ipv6.h>
15 #include <net/netns/x_tables.h>
16 
17 struct proc_dir_entry;
18 struct net_device;
19 struct sock;
20 struct ctl_table_header;
21 
22 struct net {
23 	atomic_t		count;		/* To decided when the network
24 						 *  namespace should be freed.
25 						 */
26 	atomic_t		use_count;	/* To track references we
27 						 * destroy on demand
28 						 */
29 	struct list_head	list;		/* list of network namespaces */
30 	struct work_struct	work;		/* work struct for freeing */
31 
32 	struct proc_dir_entry 	*proc_net;
33 	struct proc_dir_entry 	*proc_net_stat;
34 	struct proc_dir_entry 	*proc_net_root;
35 
36 	struct list_head	sysctl_table_headers;
37 
38 	struct net_device       *loopback_dev;          /* The loopback */
39 
40 	struct list_head 	dev_base_head;
41 	struct hlist_head 	*dev_name_head;
42 	struct hlist_head	*dev_index_head;
43 
44 	/* core fib_rules */
45 	struct list_head	rules_ops;
46 	spinlock_t		rules_mod_lock;
47 
48 	struct sock 		*rtnl;			/* rtnetlink socket */
49 
50 	/* core sysctls */
51 	struct ctl_table_header	*sysctl_core_hdr;
52 	int			sysctl_somaxconn;
53 
54 	struct netns_packet	packet;
55 	struct netns_unix	unx;
56 	struct netns_ipv4	ipv4;
57 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
58 	struct netns_ipv6	ipv6;
59 #endif
60 #ifdef CONFIG_NETFILTER
61 	struct netns_xt		xt;
62 #endif
63 };
64 
65 #ifdef CONFIG_NET
66 /* Init's network namespace */
67 extern struct net init_net;
68 #define INIT_NET_NS(net_ns) .net_ns = &init_net,
69 #else
70 #define INIT_NET_NS(net_ns)
71 #endif
72 
73 extern struct list_head net_namespace_list;
74 
75 #ifdef CONFIG_NET
76 extern struct net *copy_net_ns(unsigned long flags, struct net *net_ns);
77 #else
78 static inline struct net *copy_net_ns(unsigned long flags, struct net *net_ns)
79 {
80 	/* There is nothing to copy so this is a noop */
81 	return net_ns;
82 }
83 #endif
84 
85 #ifdef CONFIG_NET_NS
86 extern void __put_net(struct net *net);
87 
88 static inline struct net *get_net(struct net *net)
89 {
90 	atomic_inc(&net->count);
91 	return net;
92 }
93 
94 static inline struct net *maybe_get_net(struct net *net)
95 {
96 	/* Used when we know struct net exists but we
97 	 * aren't guaranteed a previous reference count
98 	 * exists.  If the reference count is zero this
99 	 * function fails and returns NULL.
100 	 */
101 	if (!atomic_inc_not_zero(&net->count))
102 		net = NULL;
103 	return net;
104 }
105 
106 static inline void put_net(struct net *net)
107 {
108 	if (atomic_dec_and_test(&net->count))
109 		__put_net(net);
110 }
111 
112 static inline struct net *hold_net(struct net *net)
113 {
114 	atomic_inc(&net->use_count);
115 	return net;
116 }
117 
118 static inline void release_net(struct net *net)
119 {
120 	atomic_dec(&net->use_count);
121 }
122 #else
123 static inline struct net *get_net(struct net *net)
124 {
125 	return net;
126 }
127 
128 static inline void put_net(struct net *net)
129 {
130 }
131 
132 static inline struct net *hold_net(struct net *net)
133 {
134 	return net;
135 }
136 
137 static inline void release_net(struct net *net)
138 {
139 }
140 
141 static inline struct net *maybe_get_net(struct net *net)
142 {
143 	return net;
144 }
145 #endif
146 
147 #define for_each_net(VAR)				\
148 	list_for_each_entry(VAR, &net_namespace_list, list)
149 
150 #ifdef CONFIG_NET_NS
151 #define __net_init
152 #define __net_exit
153 #define __net_initdata
154 #else
155 #define __net_init	__init
156 #define __net_exit	__exit_refok
157 #define __net_initdata	__initdata
158 #endif
159 
160 struct pernet_operations {
161 	struct list_head list;
162 	int (*init)(struct net *net);
163 	void (*exit)(struct net *net);
164 };
165 
166 extern int register_pernet_subsys(struct pernet_operations *);
167 extern void unregister_pernet_subsys(struct pernet_operations *);
168 extern int register_pernet_device(struct pernet_operations *);
169 extern void unregister_pernet_device(struct pernet_operations *);
170 
171 struct ctl_path;
172 struct ctl_table;
173 struct ctl_table_header;
174 extern struct ctl_table_header *register_net_sysctl_table(struct net *net,
175 	const struct ctl_path *path, struct ctl_table *table);
176 extern void unregister_net_sysctl_table(struct ctl_table_header *header);
177 
178 #endif /* __NET_NET_NAMESPACE_H */
179