xref: /openbmc/linux/include/net/net_namespace.h (revision f42b3800)
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/core.h>
12 #include <net/netns/unix.h>
13 #include <net/netns/packet.h>
14 #include <net/netns/ipv4.h>
15 #include <net/netns/ipv6.h>
16 #include <net/netns/dccp.h>
17 #include <net/netns/x_tables.h>
18 
19 struct proc_dir_entry;
20 struct net_device;
21 struct sock;
22 struct ctl_table_header;
23 struct net_generic;
24 
25 struct net {
26 	atomic_t		count;		/* To decided when the network
27 						 *  namespace should be freed.
28 						 */
29 #ifdef NETNS_REFCNT_DEBUG
30 	atomic_t		use_count;	/* To track references we
31 						 * destroy on demand
32 						 */
33 #endif
34 	struct list_head	list;		/* list of network namespaces */
35 	struct work_struct	work;		/* work struct for freeing */
36 
37 	struct proc_dir_entry 	*proc_net;
38 	struct proc_dir_entry 	*proc_net_stat;
39 
40 	struct list_head	sysctl_table_headers;
41 
42 	struct net_device       *loopback_dev;          /* The loopback */
43 
44 	struct list_head 	dev_base_head;
45 	struct hlist_head 	*dev_name_head;
46 	struct hlist_head	*dev_index_head;
47 
48 	/* core fib_rules */
49 	struct list_head	rules_ops;
50 	spinlock_t		rules_mod_lock;
51 
52 	struct sock 		*rtnl;			/* rtnetlink socket */
53 
54 	struct netns_core	core;
55 	struct netns_packet	packet;
56 	struct netns_unix	unx;
57 	struct netns_ipv4	ipv4;
58 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
59 	struct netns_ipv6	ipv6;
60 #endif
61 #if defined(CONFIG_IP_DCCP) || defined(CONFIG_IP_DCCP_MODULE)
62 	struct netns_dccp	dccp;
63 #endif
64 #ifdef CONFIG_NETFILTER
65 	struct netns_xt		xt;
66 #endif
67 	struct net_generic	*gen;
68 };
69 
70 
71 #include <linux/seq_file_net.h>
72 
73 /* Init's network namespace */
74 extern struct net init_net;
75 
76 #ifdef CONFIG_NET
77 #define INIT_NET_NS(net_ns) .net_ns = &init_net,
78 
79 extern struct net *copy_net_ns(unsigned long flags, struct net *net_ns);
80 
81 #else /* CONFIG_NET */
82 
83 #define INIT_NET_NS(net_ns)
84 
85 static inline struct net *copy_net_ns(unsigned long flags, struct net *net_ns)
86 {
87 	/* There is nothing to copy so this is a noop */
88 	return net_ns;
89 }
90 #endif /* CONFIG_NET */
91 
92 
93 extern struct list_head net_namespace_list;
94 
95 #ifdef CONFIG_NET_NS
96 extern void __put_net(struct net *net);
97 
98 static inline struct net *get_net(struct net *net)
99 {
100 	atomic_inc(&net->count);
101 	return net;
102 }
103 
104 static inline struct net *maybe_get_net(struct net *net)
105 {
106 	/* Used when we know struct net exists but we
107 	 * aren't guaranteed a previous reference count
108 	 * exists.  If the reference count is zero this
109 	 * function fails and returns NULL.
110 	 */
111 	if (!atomic_inc_not_zero(&net->count))
112 		net = NULL;
113 	return net;
114 }
115 
116 static inline void put_net(struct net *net)
117 {
118 	if (atomic_dec_and_test(&net->count))
119 		__put_net(net);
120 }
121 
122 static inline
123 int net_eq(const struct net *net1, const struct net *net2)
124 {
125 	return net1 == net2;
126 }
127 #else
128 static inline struct net *get_net(struct net *net)
129 {
130 	return net;
131 }
132 
133 static inline void put_net(struct net *net)
134 {
135 }
136 
137 static inline struct net *maybe_get_net(struct net *net)
138 {
139 	return net;
140 }
141 
142 static inline
143 int net_eq(const struct net *net1, const struct net *net2)
144 {
145 	return 1;
146 }
147 #endif
148 
149 
150 #ifdef NETNS_REFCNT_DEBUG
151 static inline struct net *hold_net(struct net *net)
152 {
153 	if (net)
154 		atomic_inc(&net->use_count);
155 	return net;
156 }
157 
158 static inline void release_net(struct net *net)
159 {
160 	if (net)
161 		atomic_dec(&net->use_count);
162 }
163 #else
164 static inline struct net *hold_net(struct net *net)
165 {
166 	return net;
167 }
168 
169 static inline void release_net(struct net *net)
170 {
171 }
172 #endif
173 
174 
175 #define for_each_net(VAR)				\
176 	list_for_each_entry(VAR, &net_namespace_list, list)
177 
178 #ifdef CONFIG_NET_NS
179 #define __net_init
180 #define __net_exit
181 #define __net_initdata
182 #else
183 #define __net_init	__init
184 #define __net_exit	__exit_refok
185 #define __net_initdata	__initdata
186 #endif
187 
188 struct pernet_operations {
189 	struct list_head list;
190 	int (*init)(struct net *net);
191 	void (*exit)(struct net *net);
192 };
193 
194 extern int register_pernet_subsys(struct pernet_operations *);
195 extern void unregister_pernet_subsys(struct pernet_operations *);
196 extern int register_pernet_device(struct pernet_operations *);
197 extern void unregister_pernet_device(struct pernet_operations *);
198 extern int register_pernet_gen_device(int *id, struct pernet_operations *);
199 extern void unregister_pernet_gen_device(int id, struct pernet_operations *);
200 
201 struct ctl_path;
202 struct ctl_table;
203 struct ctl_table_header;
204 extern struct ctl_table_header *register_net_sysctl_table(struct net *net,
205 	const struct ctl_path *path, struct ctl_table *table);
206 extern void unregister_net_sysctl_table(struct ctl_table_header *header);
207 
208 #endif /* __NET_NET_NAMESPACE_H */
209