LXR linux/include/net/net

   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#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
  20#include <net/netns/conntrack.h>
  21#endif
  22#include <net/netns/xfrm.h>
  23
  24struct proc_dir_entry;
  25struct net_device;
  26struct sock;
  27struct ctl_table_header;
  28struct net_generic;
  29struct sock;
  30
  31
  32#define NETDEV_HASHBITS    8
  33#define NETDEV_HASHENTRIES (1 << NETDEV_HASHBITS)
  34
  35struct net {
  36        atomic_t                count;          /* To decided when the network
  37                                                 *  namespace should be freed.
  38                                                 */
  39#ifdef NETNS_REFCNT_DEBUG
  40        atomic_t                use_count;      /* To track references we
  41                                                 * destroy on demand
  42                                                 */
  43#endif
  44        struct list_head        list;           /* list of network namespaces */
  45        struct list_head        cleanup_list;   /* namespaces on death row */
  46        struct list_head        exit_list;      /* Use only net_mutex */
  47
  48        struct proc_dir_entry   *proc_net;
  49        struct proc_dir_entry   *proc_net_stat;
  50
  51#ifdef CONFIG_SYSCTL
  52        struct ctl_table_set    sysctls;
  53#endif
  54
  55        struct net_device       *loopback_dev;          /* The loopback */
  56
  57        struct list_head        dev_base_head;
  58        struct hlist_head       *dev_name_head;
  59        struct hlist_head       *dev_index_head;
  60
  61        /* core fib_rules */
  62        struct list_head        rules_ops;
  63        spinlock_t              rules_mod_lock;
  64
  65        struct sock             *rtnl;                  /* rtnetlink socket */
  66        struct sock             *genl_sock;
  67
  68        struct netns_core       core;
  69        struct netns_mib        mib;
  70        struct netns_packet     packet;
  71        struct netns_unix       unx;
  72        struct netns_ipv4       ipv4;
  73#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
  74        struct netns_ipv6       ipv6;
  75#endif
  76#if defined(CONFIG_IP_DCCP) || defined(CONFIG_IP_DCCP_MODULE)
  77        struct netns_dccp       dccp;
  78#endif
  79#ifdef CONFIG_NETFILTER
  80        struct netns_xt         xt;
  81#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
  82        struct netns_ct         ct;
  83#endif
  84        struct sock             *nfnl;
  85        struct sock             *nfnl_stash;
  86#endif
  87#ifdef CONFIG_XFRM
  88        struct netns_xfrm       xfrm;
  89#endif
  90#ifdef CONFIG_WEXT_CORE
  91        struct sk_buff_head     wext_nlevents;
  92#endif
  93        struct net_generic      *gen;
  94};
  95
  96
  97#include <linux/seq_file_net.h>
  98
  99/* Init's network namespace */
 100extern struct net init_net;
 101
 102#ifdef CONFIG_NET
 103extern struct net *copy_net_ns(unsigned long flags, struct net *net_ns);
 104
 105#else /* CONFIG_NET */
 106static inline struct net *copy_net_ns(unsigned long flags, struct net *net_ns)
 107{
 108        /* There is nothing to copy so this is a noop */
 109        return net_ns;
 110}
 111#endif /* CONFIG_NET */
 112
 113
 114extern struct list_head net_namespace_list;
 115
 116extern struct net *get_net_ns_by_pid(pid_t pid);
 117
 118#ifdef CONFIG_NET_NS
 119extern void __put_net(struct net *net);
 120
 121static inline struct net *get_net(struct net *net)
 122{
 123        atomic_inc(&net->count);
 124        return net;
 125}
 126
 127static inline struct net *maybe_get_net(struct net *net)
 128{
 129        /* Used when we know struct net exists but we
 130         * aren't guaranteed a previous reference count
 131         * exists.  If the reference count is zero this
 132         * function fails and returns NULL.
 133         */
 134        if (!atomic_inc_not_zero(&net->count))
 135                net = NULL;
 136        return net;
 137}
 138
 139static inline void put_net(struct net *net)
 140{
 141        if (atomic_dec_and_test(&net->count))
 142                __put_net(net);
 143}
 144
 145static inline
 146int net_eq(const struct net *net1, const struct net *net2)
 147{
 148        return net1 == net2;
 149}
 150#else
 151
 152static inline struct net *get_net(struct net *net)
 153{
 154        return net;
 155}
 156
 157static inline void put_net(struct net *net)
 158{
 159}
 160
 161static inline struct net *maybe_get_net(struct net *net)
 162{
 163        return net;
 164}
 165
 166static inline
 167int net_eq(const struct net *net1, const struct net *net2)
 168{
 169        return 1;
 170}
 171#endif
 172
 173
 174#ifdef NETNS_REFCNT_DEBUG
 175static inline struct net *hold_net(struct net *net)
 176{
 177        if (net)
 178                atomic_inc(&net->use_count);
 179        return net;
 180}
 181
 182static inline void release_net(struct net *net)
 183{
 184        if (net)
 185                atomic_dec(&net->use_count);
 186}
 187#else
 188static inline struct net *hold_net(struct net *net)
 189{
 190        return net;
 191}
 192
 193static inline void release_net(struct net *net)
 194{
 195}
 196#endif
 197
 198#ifdef CONFIG_NET_NS
 199
 200static inline void write_pnet(struct net **pnet, struct net *net)
 201{
 202        *pnet = net;
 203}
 204
 205static inline struct net *read_pnet(struct net * const *pnet)
 206{
 207        return *pnet;
 208}
 209
 210#else
 211
 212#define write_pnet(pnet, net)   do { (void)(net);} while (0)
 213#define read_pnet(pnet)         (&init_net)
 214
 215#endif
 216
 217#define for_each_net(VAR)                               \
 218        list_for_each_entry(VAR, &net_namespace_list, list)
 219
 220#define for_each_net_rcu(VAR)                           \
 221        list_for_each_entry_rcu(VAR, &net_namespace_list, list)
 222
 223#ifdef CONFIG_NET_NS
 224#define __net_init
 225#define __net_exit
 226#define __net_initdata
 227#else
 228#define __net_init      __init
 229#define __net_exit      __exit_refok
 230#define __net_initdata  __initdata
 231#endif
 232
 233struct pernet_operations {
 234        struct list_head list;
 235        int (*init)(struct net *net);
 236        void (*exit)(struct net *net);
 237        void (*exit_batch)(struct list_head *net_exit_list);
 238        int *id;
 239        size_t size;
 240};
 241
 242/*
 243 * Use these carefully.  If you implement a network device and it
 244 * needs per network namespace operations use device pernet operations,
 245 * otherwise use pernet subsys operations.
 246 *
 247 * Network interfaces need to be removed from a dying netns _before_
 248 * subsys notifiers can be called, as most of the network code cleanup
 249 * (which is done from subsys notifiers) runs with the assumption that
 250 * dev_remove_pack has been called so no new packets will arrive during
 251 * and after the cleanup functions have been called.  dev_remove_pack
 252 * is not per namespace so instead the guarantee of no more packets
 253 * arriving in a network namespace is provided by ensuring that all
 254 * network devices and all sockets have left the network namespace
 255 * before the cleanup methods are called.
 256 *
 257 * For the longest time the ipv4 icmp code was registered as a pernet
 258 * device which caused kernel oops, and panics during network
 259 * namespace cleanup.   So please don't get this wrong.
 260 */
 261extern int register_pernet_subsys(struct pernet_operations *);
 262extern void unregister_pernet_subsys(struct pernet_operations *);
 263extern int register_pernet_device(struct pernet_operations *);
 264extern void unregister_pernet_device(struct pernet_operations *);
 265
 266struct ctl_path;
 267struct ctl_table;
 268struct ctl_table_header;
 269
 270extern struct ctl_table_header *register_net_sysctl_table(struct net *net,
 271        const struct ctl_path *path, struct ctl_table *table);
 272extern struct ctl_table_header *register_net_sysctl_rotable(
 273        const struct ctl_path *path, struct ctl_table *table);
 274extern void unregister_net_sysctl_table(struct ctl_table_header *header);
 275
 276#endif /* __NET_NET_NAMESPACE_H */
 277