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 #ifdef CONFIG_NET
  64 #include <linux/seq_file_net.h>
  65
  66 /* Init's network namespace */
  67 extern struct net init_net;
  68 #define INIT_NET_NS(net_ns) .net_ns = &init_net,
  69
  70 extern struct net *copy_net_ns(unsigned long flags, struct net *net_ns);
  71
  72 #else /* CONFIG_NET */
  73
  74 #define INIT_NET_NS(net_ns)
  75
  76 static inline struct net *copy_net_ns(unsigned long flags, struct net *net_ns)
  77 {
  78         /* There is nothing to copy so this is a noop */
  79         return net_ns;
  80 }
  81 #endif /* CONFIG_NET */
  82
  83
  84 extern struct list_head net_namespace_list;
  85
  86 #ifdef CONFIG_NET_NS
  87 extern void __put_net(struct net *net);
  88
  89 static inline struct net *get_net(struct net *net)
  90 {
  91         atomic_inc(&net->count);
  92         return net;
  93 }
  94
  95 static inline struct net *maybe_get_net(struct net *net)
  96 {
  97         /* Used when we know struct net exists but we
  98          * aren't guaranteed a previous reference count
  99          * exists.  If the reference count is zero this
 100          * function fails and returns NULL.
 101          */
 102         if (!atomic_inc_not_zero(&net->count))
 103                 net = NULL;
 104         return net;
 105 }
 106
 107 static inline void put_net(struct net *net)
 108 {
 109         if (atomic_dec_and_test(&net->count))
 110                 __put_net(net);
 111 }
 112
 113 static inline struct net *hold_net(struct net *net)
 114 {
 115         atomic_inc(&net->use_count);
 116         return net;
 117 }
 118
 119 static inline void release_net(struct net *net)
 120 {
 121         atomic_dec(&net->use_count);
 122 }
 123
 124 static inline
 125 int net_eq(const struct net *net1, const struct net *net2)
 126 {
 127         return net1 == net2;
 128 }
 129 #else
 130 static inline struct net *get_net(struct net *net)
 131 {
 132         return net;
 133 }
 134
 135 static inline void put_net(struct net *net)
 136 {
 137 }
 138
 139 static inline struct net *hold_net(struct net *net)
 140 {
 141         return net;
 142 }
 143
 144 static inline void release_net(struct net *net)
 145 {
 146 }
 147
 148 static inline struct net *maybe_get_net(struct net *net)
 149 {
 150         return net;
 151 }
 152
 153 static inline
 154 int net_eq(const struct net *net1, const struct net *net2)
 155 {
 156         return 1;
 157 }
 158 #endif
 159
 160 #define for_each_net(VAR)                               \
 161         list_for_each_entry(VAR, &net_namespace_list, list)
 162
 163 #ifdef CONFIG_NET_NS
 164 #define __net_init
 165 #define __net_exit
 166 #define __net_initdata
 167 #else
 168 #define __net_init      __init
 169 #define __net_exit      __exit_refok
 170 #define __net_initdata  __initdata
 171 #endif
 172
 173 struct pernet_operations {
 174         struct list_head list;
 175         int (*init)(struct net *net);
 176         void (*exit)(struct net *net);
 177 };
 178
 179 extern int register_pernet_subsys(struct pernet_operations *);
 180 extern void unregister_pernet_subsys(struct pernet_operations *);
 181 extern int register_pernet_device(struct pernet_operations *);
 182 extern void unregister_pernet_device(struct pernet_operations *);
 183
 184 struct ctl_path;
 185 struct ctl_table;
 186 struct ctl_table_header;
 187 extern struct ctl_table_header *register_net_sysctl_table(struct net *net,
 188         const struct ctl_path *path, struct ctl_table *table);
 189 extern void unregister_net_sysctl_table(struct ctl_table_header *header);
 190
 191 #endif /* __NET_NET_NAMESPACE_H */