xref: /openbmc/linux/include/net/net_namespace.h (revision 545e4006)
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/mib.h>
13 #include <net/netns/unix.h>
14 #include <net/netns/packet.h>
15 #include <net/netns/ipv4.h>
16 #include <net/netns/ipv6.h>
17 #include <net/netns/dccp.h>
18 #include <net/netns/x_tables.h>
19 
20 struct proc_dir_entry;
21 struct net_device;
22 struct sock;
23 struct ctl_table_header;
24 struct net_generic;
25 
26 struct net {
27 	atomic_t		count;		/* To decided when the network
28 						 *  namespace should be freed.
29 						 */
30 #ifdef NETNS_REFCNT_DEBUG
31 	atomic_t		use_count;	/* To track references we
32 						 * destroy on demand
33 						 */
34 #endif
35 	struct list_head	list;		/* list of network namespaces */
36 	struct work_struct	work;		/* work struct for freeing */
37 
38 	struct proc_dir_entry 	*proc_net;
39 	struct proc_dir_entry 	*proc_net_stat;
40 
41 	struct list_head	sysctl_table_headers;
42 
43 	struct net_device       *loopback_dev;          /* The loopback */
44 
45 	struct list_head 	dev_base_head;
46 	struct hlist_head 	*dev_name_head;
47 	struct hlist_head	*dev_index_head;
48 
49 	/* core fib_rules */
50 	struct list_head	rules_ops;
51 	spinlock_t		rules_mod_lock;
52 
53 	struct sock 		*rtnl;			/* rtnetlink socket */
54 
55 	struct netns_core	core;
56 	struct netns_mib	mib;
57 	struct netns_packet	packet;
58 	struct netns_unix	unx;
59 	struct netns_ipv4	ipv4;
60 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
61 	struct netns_ipv6	ipv6;
62 #endif
63 #if defined(CONFIG_IP_DCCP) || defined(CONFIG_IP_DCCP_MODULE)
64 	struct netns_dccp	dccp;
65 #endif
66 #ifdef CONFIG_NETFILTER
67 	struct netns_xt		xt;
68 #endif
69 	struct net_generic	*gen;
70 };
71 
72 
73 #include <linux/seq_file_net.h>
74 
75 /* Init's network namespace */
76 extern struct net init_net;
77 
78 #ifdef CONFIG_NET
79 #define INIT_NET_NS(net_ns) .net_ns = &init_net,
80 
81 extern struct net *copy_net_ns(unsigned long flags, struct net *net_ns);
82 
83 #else /* CONFIG_NET */
84 
85 #define INIT_NET_NS(net_ns)
86 
87 static inline struct net *copy_net_ns(unsigned long flags, struct net *net_ns)
88 {
89 	/* There is nothing to copy so this is a noop */
90 	return net_ns;
91 }
92 #endif /* CONFIG_NET */
93 
94 
95 extern struct list_head net_namespace_list;
96 
97 #ifdef CONFIG_NET_NS
98 extern void __put_net(struct net *net);
99 
100 static inline int net_alive(struct net *net)
101 {
102 	return net && atomic_read(&net->count);
103 }
104 
105 static inline struct net *get_net(struct net *net)
106 {
107 	atomic_inc(&net->count);
108 	return net;
109 }
110 
111 static inline struct net *maybe_get_net(struct net *net)
112 {
113 	/* Used when we know struct net exists but we
114 	 * aren't guaranteed a previous reference count
115 	 * exists.  If the reference count is zero this
116 	 * function fails and returns NULL.
117 	 */
118 	if (!atomic_inc_not_zero(&net->count))
119 		net = NULL;
120 	return net;
121 }
122 
123 static inline void put_net(struct net *net)
124 {
125 	if (atomic_dec_and_test(&net->count))
126 		__put_net(net);
127 }
128 
129 static inline
130 int net_eq(const struct net *net1, const struct net *net2)
131 {
132 	return net1 == net2;
133 }
134 #else
135 
136 static inline int net_alive(struct net *net)
137 {
138 	return 1;
139 }
140 
141 static inline struct net *get_net(struct net *net)
142 {
143 	return net;
144 }
145 
146 static inline void put_net(struct net *net)
147 {
148 }
149 
150 static inline struct net *maybe_get_net(struct net *net)
151 {
152 	return net;
153 }
154 
155 static inline
156 int net_eq(const struct net *net1, const struct net *net2)
157 {
158 	return 1;
159 }
160 #endif
161 
162 
163 #ifdef NETNS_REFCNT_DEBUG
164 static inline struct net *hold_net(struct net *net)
165 {
166 	if (net)
167 		atomic_inc(&net->use_count);
168 	return net;
169 }
170 
171 static inline void release_net(struct net *net)
172 {
173 	if (net)
174 		atomic_dec(&net->use_count);
175 }
176 #else
177 static inline struct net *hold_net(struct net *net)
178 {
179 	return net;
180 }
181 
182 static inline void release_net(struct net *net)
183 {
184 }
185 #endif
186 
187 
188 #define for_each_net(VAR)				\
189 	list_for_each_entry(VAR, &net_namespace_list, list)
190 
191 #ifdef CONFIG_NET_NS
192 #define __net_init
193 #define __net_exit
194 #define __net_initdata
195 #else
196 #define __net_init	__init
197 #define __net_exit	__exit_refok
198 #define __net_initdata	__initdata
199 #endif
200 
201 struct pernet_operations {
202 	struct list_head list;
203 	int (*init)(struct net *net);
204 	void (*exit)(struct net *net);
205 };
206 
207 extern int register_pernet_subsys(struct pernet_operations *);
208 extern void unregister_pernet_subsys(struct pernet_operations *);
209 extern int register_pernet_device(struct pernet_operations *);
210 extern void unregister_pernet_device(struct pernet_operations *);
211 extern int register_pernet_gen_device(int *id, struct pernet_operations *);
212 extern void unregister_pernet_gen_device(int id, struct pernet_operations *);
213 
214 struct ctl_path;
215 struct ctl_table;
216 struct ctl_table_header;
217 
218 extern struct ctl_table_header *register_net_sysctl_table(struct net *net,
219 	const struct ctl_path *path, struct ctl_table *table);
220 extern struct ctl_table_header *register_net_sysctl_rotable(
221 	const struct ctl_path *path, struct ctl_table *table);
222 extern void unregister_net_sysctl_table(struct ctl_table_header *header);
223 
224 #endif /* __NET_NET_NAMESPACE_H */
225