blob: 5bbdbf0d3664ce592f680d9670f26f7f96ce92cc [file] [log] [blame]
Eric W. Biederman5f256be2007-09-12 11:50:50 +02001#include <linux/workqueue.h>
2#include <linux/rtnetlink.h>
3#include <linux/cache.h>
4#include <linux/slab.h>
5#include <linux/list.h>
6#include <linux/delay.h>
Eric W. Biederman9dd776b2007-09-26 22:04:26 -07007#include <linux/sched.h>
Pavel Emelyanovc93cf612008-04-15 00:35:23 -07008#include <linux/idr.h>
Johannes Berg11a28d32009-07-10 09:51:33 +00009#include <linux/rculist.h>
Johannes Berg30ffee82009-07-10 09:51:35 +000010#include <linux/nsproxy.h>
Eric W. Biedermanf0630522011-05-04 17:51:50 -070011#include <linux/proc_fs.h>
12#include <linux/file.h>
Eric W. Biederman5f256be2007-09-12 11:50:50 +020013#include <net/net_namespace.h>
Pavel Emelyanovdec827d2008-04-15 00:36:08 -070014#include <net/netns/generic.h>
Eric W. Biederman5f256be2007-09-12 11:50:50 +020015
16/*
17 * Our network namespace constructor/destructor lists
18 */
19
20static LIST_HEAD(pernet_list);
21static struct list_head *first_device = &pernet_list;
22static DEFINE_MUTEX(net_mutex);
23
Eric W. Biederman5f256be2007-09-12 11:50:50 +020024LIST_HEAD(net_namespace_list);
Alexey Dobriyanb76a4612008-10-08 11:35:06 +020025EXPORT_SYMBOL_GPL(net_namespace_list);
Eric W. Biederman5f256be2007-09-12 11:50:50 +020026
Eric W. Biederman5f256be2007-09-12 11:50:50 +020027struct net init_net;
Denis V. Lunevff4b9502008-01-22 22:05:33 -080028EXPORT_SYMBOL(init_net);
Eric W. Biederman5f256be2007-09-12 11:50:50 +020029
Pavel Emelyanovdec827d2008-04-15 00:36:08 -070030#define INITIAL_NET_GEN_PTRS 13 /* +1 for len +2 for rcu_head */
31
Jiri Pirko05fceb42010-04-23 01:40:47 +000032static int net_assign_generic(struct net *net, int id, void *data)
33{
34 struct net_generic *ng, *old_ng;
35
36 BUG_ON(!mutex_is_locked(&net_mutex));
37 BUG_ON(id == 0);
38
Eric Dumazet1c877332010-10-25 03:20:11 +000039 old_ng = rcu_dereference_protected(net->gen,
40 lockdep_is_held(&net_mutex));
41 ng = old_ng;
Jiri Pirko05fceb42010-04-23 01:40:47 +000042 if (old_ng->len >= id)
43 goto assign;
44
45 ng = kzalloc(sizeof(struct net_generic) +
46 id * sizeof(void *), GFP_KERNEL);
47 if (ng == NULL)
48 return -ENOMEM;
49
50 /*
51 * Some synchronisation notes:
52 *
53 * The net_generic explores the net->gen array inside rcu
54 * read section. Besides once set the net->gen->ptr[x]
55 * pointer never changes (see rules in netns/generic.h).
56 *
57 * That said, we simply duplicate this array and schedule
58 * the old copy for kfree after a grace period.
59 */
60
61 ng->len = id;
62 memcpy(&ng->ptr, &old_ng->ptr, old_ng->len * sizeof(void*));
63
64 rcu_assign_pointer(net->gen, ng);
Lai Jiangshan04d4dfe2011-03-18 12:06:32 +080065 kfree_rcu(old_ng, rcu);
Jiri Pirko05fceb42010-04-23 01:40:47 +000066assign:
67 ng->ptr[id - 1] = data;
68 return 0;
69}
70
Eric W. Biedermanf875bae2009-11-29 22:25:28 +000071static int ops_init(const struct pernet_operations *ops, struct net *net)
72{
73 int err;
74 if (ops->id && ops->size) {
75 void *data = kzalloc(ops->size, GFP_KERNEL);
76 if (!data)
77 return -ENOMEM;
78
79 err = net_assign_generic(net, *ops->id, data);
80 if (err) {
81 kfree(data);
82 return err;
83 }
84 }
85 if (ops->init)
86 return ops->init(net);
87 return 0;
88}
89
90static void ops_free(const struct pernet_operations *ops, struct net *net)
91{
92 if (ops->id && ops->size) {
93 int id = *ops->id;
94 kfree(net_generic(net, id));
95 }
96}
97
Eric W. Biederman72ad9372009-12-03 02:29:03 +000098static void ops_exit_list(const struct pernet_operations *ops,
99 struct list_head *net_exit_list)
100{
101 struct net *net;
102 if (ops->exit) {
103 list_for_each_entry(net, net_exit_list, exit_list)
104 ops->exit(net);
105 }
Eric W. Biederman72ad9372009-12-03 02:29:03 +0000106 if (ops->exit_batch)
107 ops->exit_batch(net_exit_list);
108}
109
110static void ops_free_list(const struct pernet_operations *ops,
111 struct list_head *net_exit_list)
112{
113 struct net *net;
114 if (ops->size && ops->id) {
115 list_for_each_entry(net, net_exit_list, exit_list)
116 ops_free(ops, net);
117 }
118}
119
Pavel Emelyanov6a1a3b92007-11-01 00:44:50 -0700120/*
121 * setup_net runs the initializers for the network namespace object.
122 */
Pavel Emelyanov1a2ee932007-11-01 00:45:59 -0700123static __net_init int setup_net(struct net *net)
Pavel Emelyanov6a1a3b92007-11-01 00:44:50 -0700124{
125 /* Must be called with net_mutex held */
Eric W. Biedermanf875bae2009-11-29 22:25:28 +0000126 const struct pernet_operations *ops, *saved_ops;
Daniel Lezcano486a87f2009-02-22 00:07:53 -0800127 int error = 0;
Eric W. Biederman72ad9372009-12-03 02:29:03 +0000128 LIST_HEAD(net_exit_list);
Pavel Emelyanov6a1a3b92007-11-01 00:44:50 -0700129
130 atomic_set(&net->count, 1);
Al Viroa685e082011-06-08 21:13:01 -0400131 atomic_set(&net->passive, 1);
Thomas Graf4e985ad2011-06-21 03:11:20 +0000132 net->dev_base_seq = 1;
Daniel Lezcano486a87f2009-02-22 00:07:53 -0800133
Denis V. Lunev5d1e4462008-04-16 01:58:04 -0700134#ifdef NETNS_REFCNT_DEBUG
Pavel Emelyanov6a1a3b92007-11-01 00:44:50 -0700135 atomic_set(&net->use_count, 0);
Denis V. Lunev5d1e4462008-04-16 01:58:04 -0700136#endif
Pavel Emelyanov6a1a3b92007-11-01 00:44:50 -0700137
Pavel Emelyanov6a1a3b92007-11-01 00:44:50 -0700138 list_for_each_entry(ops, &pernet_list, list) {
Eric W. Biedermanf875bae2009-11-29 22:25:28 +0000139 error = ops_init(ops, net);
140 if (error < 0)
141 goto out_undo;
Pavel Emelyanov6a1a3b92007-11-01 00:44:50 -0700142 }
143out:
144 return error;
145
146out_undo:
147 /* Walk through the list backwards calling the exit functions
148 * for the pernet modules whose init functions did not fail.
149 */
Eric W. Biederman72ad9372009-12-03 02:29:03 +0000150 list_add(&net->exit_list, &net_exit_list);
Eric W. Biedermanf875bae2009-11-29 22:25:28 +0000151 saved_ops = ops;
Eric W. Biederman72ad9372009-12-03 02:29:03 +0000152 list_for_each_entry_continue_reverse(ops, &pernet_list, list)
153 ops_exit_list(ops, &net_exit_list);
154
Eric W. Biedermanf875bae2009-11-29 22:25:28 +0000155 ops = saved_ops;
156 list_for_each_entry_continue_reverse(ops, &pernet_list, list)
Eric W. Biederman72ad9372009-12-03 02:29:03 +0000157 ops_free_list(ops, &net_exit_list);
Pavel Emelyanov6a1a3b92007-11-01 00:44:50 -0700158
159 rcu_barrier();
160 goto out;
161}
162
Daniel Lezcano486a87f2009-02-22 00:07:53 -0800163static struct net_generic *net_alloc_generic(void)
164{
165 struct net_generic *ng;
166 size_t generic_size = sizeof(struct net_generic) +
167 INITIAL_NET_GEN_PTRS * sizeof(void *);
168
169 ng = kzalloc(generic_size, GFP_KERNEL);
170 if (ng)
171 ng->len = INITIAL_NET_GEN_PTRS;
172
173 return ng;
174}
175
Clemens Nossebe47d42009-02-23 15:37:35 -0800176#ifdef CONFIG_NET_NS
177static struct kmem_cache *net_cachep;
178static struct workqueue_struct *netns_wq;
179
Eric W. Biederman5f256be2007-09-12 11:50:50 +0200180static struct net *net_alloc(void)
181{
Daniel Lezcano486a87f2009-02-22 00:07:53 -0800182 struct net *net = NULL;
183 struct net_generic *ng;
184
185 ng = net_alloc_generic();
186 if (!ng)
187 goto out;
188
189 net = kmem_cache_zalloc(net_cachep, GFP_KERNEL);
190 if (!net)
191 goto out_free;
192
193 rcu_assign_pointer(net->gen, ng);
194out:
195 return net;
196
197out_free:
198 kfree(ng);
199 goto out;
Eric W. Biederman5f256be2007-09-12 11:50:50 +0200200}
Eric W. Biederman5f256be2007-09-12 11:50:50 +0200201
Johann Felix Soden45a19b02007-11-07 01:30:30 -0800202static void net_free(struct net *net)
203{
Denis V. Lunev5d1e4462008-04-16 01:58:04 -0700204#ifdef NETNS_REFCNT_DEBUG
Johann Felix Soden45a19b02007-11-07 01:30:30 -0800205 if (unlikely(atomic_read(&net->use_count) != 0)) {
206 printk(KERN_EMERG "network namespace not free! Usage: %d\n",
207 atomic_read(&net->use_count));
208 return;
209 }
Denis V. Lunev5d1e4462008-04-16 01:58:04 -0700210#endif
Alexey Dobriyan4ef079c2008-10-14 22:54:48 -0700211 kfree(net->gen);
Johann Felix Soden45a19b02007-11-07 01:30:30 -0800212 kmem_cache_free(net_cachep, net);
213}
214
Al Viroa685e082011-06-08 21:13:01 -0400215void net_drop_ns(void *p)
216{
217 struct net *ns = p;
218 if (ns && atomic_dec_and_test(&ns->passive))
219 net_free(ns);
220}
221
Rob Landley911cb192011-04-15 02:26:25 +0000222struct net *copy_net_ns(unsigned long flags, struct net *old_net)
Pavel Emelyanov6a1a3b92007-11-01 00:44:50 -0700223{
Alexey Dobriyan088eb2d2009-05-04 11:12:14 -0700224 struct net *net;
225 int rv;
Pavel Emelyanov6a1a3b92007-11-01 00:44:50 -0700226
Rob Landley911cb192011-04-15 02:26:25 +0000227 if (!(flags & CLONE_NEWNET))
228 return get_net(old_net);
229
Alexey Dobriyan088eb2d2009-05-04 11:12:14 -0700230 net = net_alloc();
231 if (!net)
232 return ERR_PTR(-ENOMEM);
Pavel Emelyanov6a1a3b92007-11-01 00:44:50 -0700233 mutex_lock(&net_mutex);
Alexey Dobriyan088eb2d2009-05-04 11:12:14 -0700234 rv = setup_net(net);
235 if (rv == 0) {
Daniel Lezcano486a87f2009-02-22 00:07:53 -0800236 rtnl_lock();
Johannes Berg11a28d32009-07-10 09:51:33 +0000237 list_add_tail_rcu(&net->list, &net_namespace_list);
Daniel Lezcano486a87f2009-02-22 00:07:53 -0800238 rtnl_unlock();
239 }
Pavel Emelyanov6a1a3b92007-11-01 00:44:50 -0700240 mutex_unlock(&net_mutex);
Alexey Dobriyan088eb2d2009-05-04 11:12:14 -0700241 if (rv < 0) {
Al Viroa685e082011-06-08 21:13:01 -0400242 net_drop_ns(net);
Alexey Dobriyan088eb2d2009-05-04 11:12:14 -0700243 return ERR_PTR(rv);
244 }
245 return net;
246}
Daniel Lezcano486a87f2009-02-22 00:07:53 -0800247
Eric W. Biederman2b035b32009-11-29 22:25:27 +0000248static DEFINE_SPINLOCK(cleanup_list_lock);
249static LIST_HEAD(cleanup_list); /* Must hold cleanup_list_lock to touch */
250
Eric W. Biederman5f256be2007-09-12 11:50:50 +0200251static void cleanup_net(struct work_struct *work)
252{
Eric W. Biedermanf875bae2009-11-29 22:25:28 +0000253 const struct pernet_operations *ops;
Eric W. Biederman2b035b32009-11-29 22:25:27 +0000254 struct net *net, *tmp;
255 LIST_HEAD(net_kill_list);
Eric W. Biederman72ad9372009-12-03 02:29:03 +0000256 LIST_HEAD(net_exit_list);
Eric W. Biederman5f256be2007-09-12 11:50:50 +0200257
Eric W. Biederman2b035b32009-11-29 22:25:27 +0000258 /* Atomically snapshot the list of namespaces to cleanup */
259 spin_lock_irq(&cleanup_list_lock);
260 list_replace_init(&cleanup_list, &net_kill_list);
261 spin_unlock_irq(&cleanup_list_lock);
Eric W. Biederman5f256be2007-09-12 11:50:50 +0200262
263 mutex_lock(&net_mutex);
264
265 /* Don't let anyone else find us. */
Eric W. Biedermanf4618d32007-09-26 22:40:08 -0700266 rtnl_lock();
Eric W. Biederman72ad9372009-12-03 02:29:03 +0000267 list_for_each_entry(net, &net_kill_list, cleanup_list) {
Eric W. Biederman2b035b32009-11-29 22:25:27 +0000268 list_del_rcu(&net->list);
Eric W. Biederman72ad9372009-12-03 02:29:03 +0000269 list_add_tail(&net->exit_list, &net_exit_list);
270 }
Eric W. Biedermanf4618d32007-09-26 22:40:08 -0700271 rtnl_unlock();
Eric W. Biederman5f256be2007-09-12 11:50:50 +0200272
Johannes Berg11a28d32009-07-10 09:51:33 +0000273 /*
274 * Another CPU might be rcu-iterating the list, wait for it.
275 * This needs to be before calling the exit() notifiers, so
276 * the rcu_barrier() below isn't sufficient alone.
277 */
278 synchronize_rcu();
279
Eric W. Biederman5f256be2007-09-12 11:50:50 +0200280 /* Run all of the network namespace exit methods */
Eric W. Biederman72ad9372009-12-03 02:29:03 +0000281 list_for_each_entry_reverse(ops, &pernet_list, list)
282 ops_exit_list(ops, &net_exit_list);
283
Eric W. Biedermanf875bae2009-11-29 22:25:28 +0000284 /* Free the net generic variables */
Eric W. Biederman72ad9372009-12-03 02:29:03 +0000285 list_for_each_entry_reverse(ops, &pernet_list, list)
286 ops_free_list(ops, &net_exit_list);
Eric W. Biederman5f256be2007-09-12 11:50:50 +0200287
288 mutex_unlock(&net_mutex);
289
290 /* Ensure there are no outstanding rcu callbacks using this
291 * network namespace.
292 */
293 rcu_barrier();
294
295 /* Finally it is safe to free my network namespace structure */
Eric W. Biederman72ad9372009-12-03 02:29:03 +0000296 list_for_each_entry_safe(net, tmp, &net_exit_list, exit_list) {
297 list_del_init(&net->exit_list);
Al Viroa685e082011-06-08 21:13:01 -0400298 net_drop_ns(net);
Eric W. Biederman2b035b32009-11-29 22:25:27 +0000299 }
Eric W. Biederman5f256be2007-09-12 11:50:50 +0200300}
Eric W. Biederman2b035b32009-11-29 22:25:27 +0000301static DECLARE_WORK(net_cleanup_work, cleanup_net);
Eric W. Biederman5f256be2007-09-12 11:50:50 +0200302
Eric W. Biederman5f256be2007-09-12 11:50:50 +0200303void __put_net(struct net *net)
304{
305 /* Cleanup the network namespace in process context */
Eric W. Biederman2b035b32009-11-29 22:25:27 +0000306 unsigned long flags;
307
308 spin_lock_irqsave(&cleanup_list_lock, flags);
309 list_add(&net->cleanup_list, &cleanup_list);
310 spin_unlock_irqrestore(&cleanup_list_lock, flags);
311
312 queue_work(netns_wq, &net_cleanup_work);
Eric W. Biederman5f256be2007-09-12 11:50:50 +0200313}
314EXPORT_SYMBOL_GPL(__put_net);
315
Stephen Rothwell956c9202011-05-12 13:51:13 +1000316struct net *get_net_ns_by_fd(int fd)
317{
318 struct proc_inode *ei;
319 struct file *file;
320 struct net *net;
321
Stephen Rothwell956c9202011-05-12 13:51:13 +1000322 file = proc_ns_fget(fd);
Al Viroc316e6a2011-06-05 00:37:35 +0000323 if (IS_ERR(file))
324 return ERR_CAST(file);
Stephen Rothwell956c9202011-05-12 13:51:13 +1000325
326 ei = PROC_I(file->f_dentry->d_inode);
Al Viroc316e6a2011-06-05 00:37:35 +0000327 if (ei->ns_ops == &netns_operations)
328 net = get_net(ei->ns);
329 else
330 net = ERR_PTR(-EINVAL);
Stephen Rothwell956c9202011-05-12 13:51:13 +1000331
Al Viroc316e6a2011-06-05 00:37:35 +0000332 fput(file);
Stephen Rothwell956c9202011-05-12 13:51:13 +1000333 return net;
334}
335
Pavel Emelyanov6a1a3b92007-11-01 00:44:50 -0700336#else
Eric W. Biederman9dd776b2007-09-26 22:04:26 -0700337struct net *copy_net_ns(unsigned long flags, struct net *old_net)
338{
Pavel Emelyanov6a1a3b92007-11-01 00:44:50 -0700339 if (flags & CLONE_NEWNET)
340 return ERR_PTR(-EINVAL);
341 return old_net;
Eric W. Biederman9dd776b2007-09-26 22:04:26 -0700342}
Stephen Rothwell956c9202011-05-12 13:51:13 +1000343
344struct net *get_net_ns_by_fd(int fd)
345{
346 return ERR_PTR(-EINVAL);
347}
Pavel Emelyanov6a1a3b92007-11-01 00:44:50 -0700348#endif
Eric W. Biederman9dd776b2007-09-26 22:04:26 -0700349
Johannes Berg30ffee82009-07-10 09:51:35 +0000350struct net *get_net_ns_by_pid(pid_t pid)
351{
352 struct task_struct *tsk;
353 struct net *net;
354
355 /* Lookup the network namespace */
356 net = ERR_PTR(-ESRCH);
357 rcu_read_lock();
358 tsk = find_task_by_vpid(pid);
359 if (tsk) {
360 struct nsproxy *nsproxy;
361 nsproxy = task_nsproxy(tsk);
362 if (nsproxy)
363 net = get_net(nsproxy->net_ns);
364 }
365 rcu_read_unlock();
366 return net;
367}
368EXPORT_SYMBOL_GPL(get_net_ns_by_pid);
369
Eric W. Biederman5f256be2007-09-12 11:50:50 +0200370static int __init net_ns_init(void)
371{
Daniel Lezcano486a87f2009-02-22 00:07:53 -0800372 struct net_generic *ng;
Eric W. Biederman5f256be2007-09-12 11:50:50 +0200373
Pavel Emelyanovd57a9212007-11-01 00:46:50 -0700374#ifdef CONFIG_NET_NS
Eric W. Biederman5f256be2007-09-12 11:50:50 +0200375 net_cachep = kmem_cache_create("net_namespace", sizeof(struct net),
376 SMP_CACHE_BYTES,
377 SLAB_PANIC, NULL);
Benjamin Thery3ef13552007-11-19 23:18:16 -0800378
379 /* Create workqueue for cleanup */
380 netns_wq = create_singlethread_workqueue("netns");
381 if (!netns_wq)
382 panic("Could not create netns workq");
Pavel Emelyanovd57a9212007-11-01 00:46:50 -0700383#endif
Benjamin Thery3ef13552007-11-19 23:18:16 -0800384
Daniel Lezcano486a87f2009-02-22 00:07:53 -0800385 ng = net_alloc_generic();
386 if (!ng)
387 panic("Could not allocate generic netns");
388
389 rcu_assign_pointer(init_net.gen, ng);
390
Eric W. Biederman5f256be2007-09-12 11:50:50 +0200391 mutex_lock(&net_mutex);
Stephen Hemmingerca0f3112009-05-21 15:10:31 -0700392 if (setup_net(&init_net))
393 panic("Could not setup the initial network namespace");
Eric W. Biederman5f256be2007-09-12 11:50:50 +0200394
Eric W. Biedermanf4618d32007-09-26 22:40:08 -0700395 rtnl_lock();
Johannes Berg11a28d32009-07-10 09:51:33 +0000396 list_add_tail_rcu(&init_net.list, &net_namespace_list);
Eric W. Biedermanf4618d32007-09-26 22:40:08 -0700397 rtnl_unlock();
Eric W. Biederman5f256be2007-09-12 11:50:50 +0200398
399 mutex_unlock(&net_mutex);
Eric W. Biederman5f256be2007-09-12 11:50:50 +0200400
401 return 0;
402}
403
404pure_initcall(net_ns_init);
405
Denis V. Luneved160e82007-11-13 03:23:21 -0800406#ifdef CONFIG_NET_NS
Eric W. Biedermanf875bae2009-11-29 22:25:28 +0000407static int __register_pernet_operations(struct list_head *list,
408 struct pernet_operations *ops)
Eric W. Biederman5f256be2007-09-12 11:50:50 +0200409{
Eric W. Biederman72ad9372009-12-03 02:29:03 +0000410 struct net *net;
Eric W. Biederman5f256be2007-09-12 11:50:50 +0200411 int error;
Eric W. Biederman72ad9372009-12-03 02:29:03 +0000412 LIST_HEAD(net_exit_list);
Eric W. Biederman5f256be2007-09-12 11:50:50 +0200413
Eric W. Biederman5f256be2007-09-12 11:50:50 +0200414 list_add_tail(&ops->list, list);
Eric W. Biedermanf875bae2009-11-29 22:25:28 +0000415 if (ops->init || (ops->id && ops->size)) {
Pavel Emelyanov1dba3232007-11-01 00:42:43 -0700416 for_each_net(net) {
Eric W. Biedermanf875bae2009-11-29 22:25:28 +0000417 error = ops_init(ops, net);
Eric W. Biederman5f256be2007-09-12 11:50:50 +0200418 if (error)
419 goto out_undo;
Eric W. Biederman72ad9372009-12-03 02:29:03 +0000420 list_add_tail(&net->exit_list, &net_exit_list);
Eric W. Biederman5f256be2007-09-12 11:50:50 +0200421 }
422 }
Pavel Emelyanov1dba3232007-11-01 00:42:43 -0700423 return 0;
Eric W. Biederman5f256be2007-09-12 11:50:50 +0200424
425out_undo:
426 /* If I have an error cleanup all namespaces I initialized */
427 list_del(&ops->list);
Eric W. Biederman72ad9372009-12-03 02:29:03 +0000428 ops_exit_list(ops, &net_exit_list);
429 ops_free_list(ops, &net_exit_list);
Pavel Emelyanov1dba3232007-11-01 00:42:43 -0700430 return error;
Eric W. Biederman5f256be2007-09-12 11:50:50 +0200431}
432
Eric W. Biedermanf875bae2009-11-29 22:25:28 +0000433static void __unregister_pernet_operations(struct pernet_operations *ops)
Eric W. Biederman5f256be2007-09-12 11:50:50 +0200434{
435 struct net *net;
Eric W. Biederman72ad9372009-12-03 02:29:03 +0000436 LIST_HEAD(net_exit_list);
Eric W. Biederman5f256be2007-09-12 11:50:50 +0200437
438 list_del(&ops->list);
Eric W. Biederman72ad9372009-12-03 02:29:03 +0000439 for_each_net(net)
440 list_add_tail(&net->exit_list, &net_exit_list);
441 ops_exit_list(ops, &net_exit_list);
442 ops_free_list(ops, &net_exit_list);
Eric W. Biederman5f256be2007-09-12 11:50:50 +0200443}
444
Denis V. Luneved160e82007-11-13 03:23:21 -0800445#else
446
Eric W. Biedermanf875bae2009-11-29 22:25:28 +0000447static int __register_pernet_operations(struct list_head *list,
448 struct pernet_operations *ops)
449{
450 int err = 0;
451 err = ops_init(ops, &init_net);
452 if (err)
453 ops_free(ops, &init_net);
454 return err;
455
456}
457
458static void __unregister_pernet_operations(struct pernet_operations *ops)
459{
Eric W. Biederman72ad9372009-12-03 02:29:03 +0000460 LIST_HEAD(net_exit_list);
461 list_add(&init_net.exit_list, &net_exit_list);
462 ops_exit_list(ops, &net_exit_list);
463 ops_free_list(ops, &net_exit_list);
Eric W. Biedermanf875bae2009-11-29 22:25:28 +0000464}
465
466#endif /* CONFIG_NET_NS */
467
468static DEFINE_IDA(net_generic_ids);
469
Denis V. Luneved160e82007-11-13 03:23:21 -0800470static int register_pernet_operations(struct list_head *list,
471 struct pernet_operations *ops)
472{
Eric W. Biedermanf875bae2009-11-29 22:25:28 +0000473 int error;
474
475 if (ops->id) {
476again:
477 error = ida_get_new_above(&net_generic_ids, 1, ops->id);
478 if (error < 0) {
479 if (error == -EAGAIN) {
480 ida_pre_get(&net_generic_ids, GFP_KERNEL);
481 goto again;
482 }
483 return error;
484 }
485 }
486 error = __register_pernet_operations(list, ops);
Eric W. Biederman3a765ed2009-12-03 02:29:06 +0000487 if (error) {
488 rcu_barrier();
489 if (ops->id)
490 ida_remove(&net_generic_ids, *ops->id);
491 }
Eric W. Biedermanf875bae2009-11-29 22:25:28 +0000492
493 return error;
Denis V. Luneved160e82007-11-13 03:23:21 -0800494}
495
496static void unregister_pernet_operations(struct pernet_operations *ops)
497{
Eric W. Biedermanf875bae2009-11-29 22:25:28 +0000498
499 __unregister_pernet_operations(ops);
Eric W. Biederman3a765ed2009-12-03 02:29:06 +0000500 rcu_barrier();
Eric W. Biedermanf875bae2009-11-29 22:25:28 +0000501 if (ops->id)
502 ida_remove(&net_generic_ids, *ops->id);
Denis V. Luneved160e82007-11-13 03:23:21 -0800503}
Pavel Emelyanovc93cf612008-04-15 00:35:23 -0700504
Eric W. Biederman5f256be2007-09-12 11:50:50 +0200505/**
506 * register_pernet_subsys - register a network namespace subsystem
507 * @ops: pernet operations structure for the subsystem
508 *
509 * Register a subsystem which has init and exit functions
510 * that are called when network namespaces are created and
511 * destroyed respectively.
512 *
513 * When registered all network namespace init functions are
514 * called for every existing network namespace. Allowing kernel
515 * modules to have a race free view of the set of network namespaces.
516 *
517 * When a new network namespace is created all of the init
518 * methods are called in the order in which they were registered.
519 *
520 * When a network namespace is destroyed all of the exit methods
521 * are called in the reverse of the order with which they were
522 * registered.
523 */
524int register_pernet_subsys(struct pernet_operations *ops)
525{
526 int error;
527 mutex_lock(&net_mutex);
528 error = register_pernet_operations(first_device, ops);
529 mutex_unlock(&net_mutex);
530 return error;
531}
532EXPORT_SYMBOL_GPL(register_pernet_subsys);
533
534/**
535 * unregister_pernet_subsys - unregister a network namespace subsystem
536 * @ops: pernet operations structure to manipulate
537 *
538 * Remove the pernet operations structure from the list to be
Oliver Pinter53379e52008-02-03 17:56:48 +0200539 * used when network namespaces are created or destroyed. In
Eric W. Biederman5f256be2007-09-12 11:50:50 +0200540 * addition run the exit method for all existing network
541 * namespaces.
542 */
Jiri Pirkob3c981d2010-04-25 00:49:56 -0700543void unregister_pernet_subsys(struct pernet_operations *ops)
Eric W. Biederman5f256be2007-09-12 11:50:50 +0200544{
545 mutex_lock(&net_mutex);
Jiri Pirkob3c981d2010-04-25 00:49:56 -0700546 unregister_pernet_operations(ops);
Eric W. Biederman5f256be2007-09-12 11:50:50 +0200547 mutex_unlock(&net_mutex);
548}
549EXPORT_SYMBOL_GPL(unregister_pernet_subsys);
550
551/**
552 * register_pernet_device - register a network namespace device
553 * @ops: pernet operations structure for the subsystem
554 *
555 * Register a device which has init and exit functions
556 * that are called when network namespaces are created and
557 * destroyed respectively.
558 *
559 * When registered all network namespace init functions are
560 * called for every existing network namespace. Allowing kernel
561 * modules to have a race free view of the set of network namespaces.
562 *
563 * When a new network namespace is created all of the init
564 * methods are called in the order in which they were registered.
565 *
566 * When a network namespace is destroyed all of the exit methods
567 * are called in the reverse of the order with which they were
568 * registered.
569 */
570int register_pernet_device(struct pernet_operations *ops)
571{
572 int error;
573 mutex_lock(&net_mutex);
574 error = register_pernet_operations(&pernet_list, ops);
575 if (!error && (first_device == &pernet_list))
576 first_device = &ops->list;
577 mutex_unlock(&net_mutex);
578 return error;
579}
580EXPORT_SYMBOL_GPL(register_pernet_device);
581
582/**
583 * unregister_pernet_device - unregister a network namespace netdevice
584 * @ops: pernet operations structure to manipulate
585 *
586 * Remove the pernet operations structure from the list to be
Oliver Pinter53379e52008-02-03 17:56:48 +0200587 * used when network namespaces are created or destroyed. In
Eric W. Biederman5f256be2007-09-12 11:50:50 +0200588 * addition run the exit method for all existing network
589 * namespaces.
590 */
591void unregister_pernet_device(struct pernet_operations *ops)
592{
593 mutex_lock(&net_mutex);
594 if (&ops->list == first_device)
595 first_device = first_device->next;
596 unregister_pernet_operations(ops);
597 mutex_unlock(&net_mutex);
598}
599EXPORT_SYMBOL_GPL(unregister_pernet_device);
Eric W. Biederman13b6f572010-03-07 18:14:23 -0800600
601#ifdef CONFIG_NET_NS
602static void *netns_get(struct task_struct *task)
603{
Eric W. Biedermanf0630522011-05-04 17:51:50 -0700604 struct net *net = NULL;
605 struct nsproxy *nsproxy;
606
Eric W. Biederman13b6f572010-03-07 18:14:23 -0800607 rcu_read_lock();
Eric W. Biedermanf0630522011-05-04 17:51:50 -0700608 nsproxy = task_nsproxy(task);
609 if (nsproxy)
610 net = get_net(nsproxy->net_ns);
Eric W. Biederman13b6f572010-03-07 18:14:23 -0800611 rcu_read_unlock();
Eric W. Biedermanf0630522011-05-04 17:51:50 -0700612
Eric W. Biederman13b6f572010-03-07 18:14:23 -0800613 return net;
614}
615
616static void netns_put(void *ns)
617{
618 put_net(ns);
619}
620
621static int netns_install(struct nsproxy *nsproxy, void *ns)
622{
623 put_net(nsproxy->net_ns);
624 nsproxy->net_ns = get_net(ns);
625 return 0;
626}
627
628const struct proc_ns_operations netns_operations = {
629 .name = "net",
630 .type = CLONE_NEWNET,
631 .get = netns_get,
632 .put = netns_put,
633 .install = netns_install,
634};
635#endif