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