include/net/net_namespace.h

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