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/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 */