aboutsummaryrefslogtreecommitdiff
path: root/net/core/net_namespace.c
diff options
context:
space:
mode:
authorPaul Mundt <lethal@linux-sh.org>2011-01-13 15:06:28 +0900
committerPaul Mundt <lethal@linux-sh.org>2011-01-13 15:06:28 +0900
commitf43dc23d5ea91fca257be02138a255f02d98e806 (patch)
treeb29722f6e965316e90ac97abf79923ced250dc21 /net/core/net_namespace.c
parentf8e53553f452dcbf67cb89c8cba63a1cd6eb4cc0 (diff)
parent4162cf64973df51fc885825bc9ca4d055891c49f (diff)
Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6 into common/serial-rework
Conflicts: arch/sh/kernel/cpu/sh2/setup-sh7619.c arch/sh/kernel/cpu/sh2a/setup-mxg.c arch/sh/kernel/cpu/sh2a/setup-sh7201.c arch/sh/kernel/cpu/sh2a/setup-sh7203.c arch/sh/kernel/cpu/sh2a/setup-sh7206.c arch/sh/kernel/cpu/sh3/setup-sh7705.c arch/sh/kernel/cpu/sh3/setup-sh770x.c arch/sh/kernel/cpu/sh3/setup-sh7710.c arch/sh/kernel/cpu/sh3/setup-sh7720.c arch/sh/kernel/cpu/sh4/setup-sh4-202.c arch/sh/kernel/cpu/sh4/setup-sh7750.c arch/sh/kernel/cpu/sh4/setup-sh7760.c arch/sh/kernel/cpu/sh4a/setup-sh7343.c arch/sh/kernel/cpu/sh4a/setup-sh7366.c arch/sh/kernel/cpu/sh4a/setup-sh7722.c arch/sh/kernel/cpu/sh4a/setup-sh7723.c arch/sh/kernel/cpu/sh4a/setup-sh7724.c arch/sh/kernel/cpu/sh4a/setup-sh7763.c arch/sh/kernel/cpu/sh4a/setup-sh7770.c arch/sh/kernel/cpu/sh4a/setup-sh7780.c arch/sh/kernel/cpu/sh4a/setup-sh7785.c arch/sh/kernel/cpu/sh4a/setup-sh7786.c arch/sh/kernel/cpu/sh4a/setup-shx3.c arch/sh/kernel/cpu/sh5/setup-sh5.c drivers/serial/sh-sci.c drivers/serial/sh-sci.h include/linux/serial_sci.h
Diffstat (limited to 'net/core/net_namespace.c')
-rw-r--r--net/core/net_namespace.c402
1 files changed, 239 insertions, 163 deletions
diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c
index b7292a2719d..3f860261c5e 100644
--- a/net/core/net_namespace.c
+++ b/net/core/net_namespace.c
@@ -6,6 +6,8 @@
#include <linux/delay.h>
#include <linux/sched.h>
#include <linux/idr.h>
+#include <linux/rculist.h>
+#include <linux/nsproxy.h>
#include <net/net_namespace.h>
#include <net/netns/generic.h>
@@ -25,14 +27,111 @@ EXPORT_SYMBOL(init_net);
#define INITIAL_NET_GEN_PTRS 13 /* +1 for len +2 for rcu_head */
+static void net_generic_release(struct rcu_head *rcu)
+{
+ struct net_generic *ng;
+
+ ng = container_of(rcu, struct net_generic, rcu);
+ kfree(ng);
+}
+
+static int net_assign_generic(struct net *net, int id, void *data)
+{
+ struct net_generic *ng, *old_ng;
+
+ BUG_ON(!mutex_is_locked(&net_mutex));
+ BUG_ON(id == 0);
+
+ old_ng = rcu_dereference_protected(net->gen,
+ lockdep_is_held(&net_mutex));
+ ng = old_ng;
+ if (old_ng->len >= id)
+ goto assign;
+
+ ng = kzalloc(sizeof(struct net_generic) +
+ id * sizeof(void *), GFP_KERNEL);
+ if (ng == NULL)
+ return -ENOMEM;
+
+ /*
+ * Some synchronisation notes:
+ *
+ * The net_generic explores the net->gen array inside rcu
+ * read section. Besides once set the net->gen->ptr[x]
+ * pointer never changes (see rules in netns/generic.h).
+ *
+ * That said, we simply duplicate this array and schedule
+ * the old copy for kfree after a grace period.
+ */
+
+ ng->len = id;
+ memcpy(&ng->ptr, &old_ng->ptr, old_ng->len * sizeof(void*));
+
+ rcu_assign_pointer(net->gen, ng);
+ call_rcu(&old_ng->rcu, net_generic_release);
+assign:
+ ng->ptr[id - 1] = data;
+ return 0;
+}
+
+static int ops_init(const struct pernet_operations *ops, struct net *net)
+{
+ int err;
+ if (ops->id && ops->size) {
+ void *data = kzalloc(ops->size, GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ err = net_assign_generic(net, *ops->id, data);
+ if (err) {
+ kfree(data);
+ return err;
+ }
+ }
+ if (ops->init)
+ return ops->init(net);
+ return 0;
+}
+
+static void ops_free(const struct pernet_operations *ops, struct net *net)
+{
+ if (ops->id && ops->size) {
+ int id = *ops->id;
+ kfree(net_generic(net, id));
+ }
+}
+
+static void ops_exit_list(const struct pernet_operations *ops,
+ struct list_head *net_exit_list)
+{
+ struct net *net;
+ if (ops->exit) {
+ list_for_each_entry(net, net_exit_list, exit_list)
+ ops->exit(net);
+ }
+ if (ops->exit_batch)
+ ops->exit_batch(net_exit_list);
+}
+
+static void ops_free_list(const struct pernet_operations *ops,
+ struct list_head *net_exit_list)
+{
+ struct net *net;
+ if (ops->size && ops->id) {
+ list_for_each_entry(net, net_exit_list, exit_list)
+ ops_free(ops, net);
+ }
+}
+
/*
* setup_net runs the initializers for the network namespace object.
*/
static __net_init int setup_net(struct net *net)
{
/* Must be called with net_mutex held */
- struct pernet_operations *ops;
+ const struct pernet_operations *ops, *saved_ops;
int error = 0;
+ LIST_HEAD(net_exit_list);
atomic_set(&net->count, 1);
@@ -41,11 +140,9 @@ static __net_init int setup_net(struct net *net)
#endif
list_for_each_entry(ops, &pernet_list, list) {
- if (ops->init) {
- error = ops->init(net);
- if (error < 0)
- goto out_undo;
- }
+ error = ops_init(ops, net);
+ if (error < 0)
+ goto out_undo;
}
out:
return error;
@@ -54,10 +151,14 @@ out_undo:
/* Walk through the list backwards calling the exit functions
* for the pernet modules whose init functions did not fail.
*/
- list_for_each_entry_continue_reverse(ops, &pernet_list, list) {
- if (ops->exit)
- ops->exit(net);
- }
+ list_add(&net->exit_list, &net_exit_list);
+ saved_ops = ops;
+ list_for_each_entry_continue_reverse(ops, &pernet_list, list)
+ ops_exit_list(ops, &net_exit_list);
+
+ ops = saved_ops;
+ list_for_each_entry_continue_reverse(ops, &pernet_list, list)
+ ops_free_list(ops, &net_exit_list);
rcu_barrier();
goto out;
@@ -127,7 +228,7 @@ static struct net *net_create(void)
rv = setup_net(net);
if (rv == 0) {
rtnl_lock();
- list_add_tail(&net->list, &net_namespace_list);
+ list_add_tail_rcu(&net->list, &net_namespace_list);
rtnl_unlock();
}
mutex_unlock(&net_mutex);
@@ -145,25 +246,45 @@ struct net *copy_net_ns(unsigned long flags, struct net *old_net)
return net_create();
}
+static DEFINE_SPINLOCK(cleanup_list_lock);
+static LIST_HEAD(cleanup_list); /* Must hold cleanup_list_lock to touch */
+
static void cleanup_net(struct work_struct *work)
{
- struct pernet_operations *ops;
- struct net *net;
+ const struct pernet_operations *ops;
+ struct net *net, *tmp;
+ LIST_HEAD(net_kill_list);
+ LIST_HEAD(net_exit_list);
- net = container_of(work, struct net, work);
+ /* Atomically snapshot the list of namespaces to cleanup */
+ spin_lock_irq(&cleanup_list_lock);
+ list_replace_init(&cleanup_list, &net_kill_list);
+ spin_unlock_irq(&cleanup_list_lock);
mutex_lock(&net_mutex);
/* Don't let anyone else find us. */
rtnl_lock();
- list_del(&net->list);
+ list_for_each_entry(net, &net_kill_list, cleanup_list) {
+ list_del_rcu(&net->list);
+ list_add_tail(&net->exit_list, &net_exit_list);
+ }
rtnl_unlock();
+ /*
+ * Another CPU might be rcu-iterating the list, wait for it.
+ * This needs to be before calling the exit() notifiers, so
+ * the rcu_barrier() below isn't sufficient alone.
+ */
+ synchronize_rcu();
+
/* Run all of the network namespace exit methods */
- list_for_each_entry_reverse(ops, &pernet_list, list) {
- if (ops->exit)
- ops->exit(net);
- }
+ list_for_each_entry_reverse(ops, &pernet_list, list)
+ ops_exit_list(ops, &net_exit_list);
+
+ /* Free the net generic variables */
+ list_for_each_entry_reverse(ops, &pernet_list, list)
+ ops_free_list(ops, &net_exit_list);
mutex_unlock(&net_mutex);
@@ -173,14 +294,23 @@ static void cleanup_net(struct work_struct *work)
rcu_barrier();
/* Finally it is safe to free my network namespace structure */
- net_free(net);
+ list_for_each_entry_safe(net, tmp, &net_exit_list, exit_list) {
+ list_del_init(&net->exit_list);
+ net_free(net);
+ }
}
+static DECLARE_WORK(net_cleanup_work, cleanup_net);
void __put_net(struct net *net)
{
/* Cleanup the network namespace in process context */
- INIT_WORK(&net->work, cleanup_net);
- queue_work(netns_wq, &net->work);
+ unsigned long flags;
+
+ spin_lock_irqsave(&cleanup_list_lock, flags);
+ list_add(&net->cleanup_list, &cleanup_list);
+ spin_unlock_irqrestore(&cleanup_list_lock, flags);
+
+ queue_work(netns_wq, &net_cleanup_work);
}
EXPORT_SYMBOL_GPL(__put_net);
@@ -193,6 +323,26 @@ struct net *copy_net_ns(unsigned long flags, struct net *old_net)
}
#endif
+struct net *get_net_ns_by_pid(pid_t pid)
+{
+ struct task_struct *tsk;
+ struct net *net;
+
+ /* Lookup the network namespace */
+ net = ERR_PTR(-ESRCH);
+ rcu_read_lock();
+ tsk = find_task_by_vpid(pid);
+ if (tsk) {
+ struct nsproxy *nsproxy;
+ nsproxy = task_nsproxy(tsk);
+ if (nsproxy)
+ net = get_net(nsproxy->net_ns);
+ }
+ rcu_read_unlock();
+ return net;
+}
+EXPORT_SYMBOL_GPL(get_net_ns_by_pid);
+
static int __init net_ns_init(void)
{
struct net_generic *ng;
@@ -219,7 +369,7 @@ static int __init net_ns_init(void)
panic("Could not setup the initial network namespace");
rtnl_lock();
- list_add_tail(&init_net.list, &net_namespace_list);
+ list_add_tail_rcu(&init_net.list, &net_namespace_list);
rtnl_unlock();
mutex_unlock(&net_mutex);
@@ -230,18 +380,20 @@ static int __init net_ns_init(void)
pure_initcall(net_ns_init);
#ifdef CONFIG_NET_NS
-static int register_pernet_operations(struct list_head *list,
- struct pernet_operations *ops)
+static int __register_pernet_operations(struct list_head *list,
+ struct pernet_operations *ops)
{
- struct net *net, *undo_net;
+ struct net *net;
int error;
+ LIST_HEAD(net_exit_list);
list_add_tail(&ops->list, list);
- if (ops->init) {
+ if (ops->init || (ops->id && ops->size)) {
for_each_net(net) {
- error = ops->init(net);
+ error = ops_init(ops, net);
if (error)
goto out_undo;
+ list_add_tail(&net->exit_list, &net_exit_list);
}
}
return 0;
@@ -249,45 +401,82 @@ static int register_pernet_operations(struct list_head *list,
out_undo:
/* If I have an error cleanup all namespaces I initialized */
list_del(&ops->list);
- if (ops->exit) {
- for_each_net(undo_net) {
- if (undo_net == net)
- goto undone;
- ops->exit(undo_net);
- }
- }
-undone:
+ ops_exit_list(ops, &net_exit_list);
+ ops_free_list(ops, &net_exit_list);
return error;
}
-static void unregister_pernet_operations(struct pernet_operations *ops)
+static void __unregister_pernet_operations(struct pernet_operations *ops)
{
struct net *net;
+ LIST_HEAD(net_exit_list);
list_del(&ops->list);
- if (ops->exit)
- for_each_net(net)
- ops->exit(net);
+ for_each_net(net)
+ list_add_tail(&net->exit_list, &net_exit_list);
+ ops_exit_list(ops, &net_exit_list);
+ ops_free_list(ops, &net_exit_list);
}
#else
+static int __register_pernet_operations(struct list_head *list,
+ struct pernet_operations *ops)
+{
+ int err = 0;
+ err = ops_init(ops, &init_net);
+ if (err)
+ ops_free(ops, &init_net);
+ return err;
+
+}
+
+static void __unregister_pernet_operations(struct pernet_operations *ops)
+{
+ LIST_HEAD(net_exit_list);
+ list_add(&init_net.exit_list, &net_exit_list);
+ ops_exit_list(ops, &net_exit_list);
+ ops_free_list(ops, &net_exit_list);
+}
+
+#endif /* CONFIG_NET_NS */
+
+static DEFINE_IDA(net_generic_ids);
+
static int register_pernet_operations(struct list_head *list,
struct pernet_operations *ops)
{
- if (ops->init == NULL)
- return 0;
- return ops->init(&init_net);
+ int error;
+
+ if (ops->id) {
+again:
+ error = ida_get_new_above(&net_generic_ids, 1, ops->id);
+ if (error < 0) {
+ if (error == -EAGAIN) {
+ ida_pre_get(&net_generic_ids, GFP_KERNEL);
+ goto again;
+ }
+ return error;
+ }
+ }
+ error = __register_pernet_operations(list, ops);
+ if (error) {
+ rcu_barrier();
+ if (ops->id)
+ ida_remove(&net_generic_ids, *ops->id);
+ }
+
+ return error;
}
static void unregister_pernet_operations(struct pernet_operations *ops)
{
- if (ops->exit)
- ops->exit(&init_net);
+
+ __unregister_pernet_operations(ops);
+ rcu_barrier();
+ if (ops->id)
+ ida_remove(&net_generic_ids, *ops->id);
}
-#endif
-
-static DEFINE_IDA(net_generic_ids);
/**
* register_pernet_subsys - register a network namespace subsystem
@@ -327,45 +516,13 @@ EXPORT_SYMBOL_GPL(register_pernet_subsys);
* addition run the exit method for all existing network
* namespaces.
*/
-void unregister_pernet_subsys(struct pernet_operations *module)
-{
- mutex_lock(&net_mutex);
- unregister_pernet_operations(module);
- mutex_unlock(&net_mutex);
-}
-EXPORT_SYMBOL_GPL(unregister_pernet_subsys);
-
-int register_pernet_gen_subsys(int *id, struct pernet_operations *ops)
-{
- int rv;
-
- mutex_lock(&net_mutex);
-again:
- rv = ida_get_new_above(&net_generic_ids, 1, id);
- if (rv < 0) {
- if (rv == -EAGAIN) {
- ida_pre_get(&net_generic_ids, GFP_KERNEL);
- goto again;
- }
- goto out;
- }
- rv = register_pernet_operations(first_device, ops);
- if (rv < 0)
- ida_remove(&net_generic_ids, *id);
-out:
- mutex_unlock(&net_mutex);
- return rv;
-}
-EXPORT_SYMBOL_GPL(register_pernet_gen_subsys);
-
-void unregister_pernet_gen_subsys(int id, struct pernet_operations *ops)
+void unregister_pernet_subsys(struct pernet_operations *ops)
{
mutex_lock(&net_mutex);
unregister_pernet_operations(ops);
- ida_remove(&net_generic_ids, id);
mutex_unlock(&net_mutex);
}
-EXPORT_SYMBOL_GPL(unregister_pernet_gen_subsys);
+EXPORT_SYMBOL_GPL(unregister_pernet_subsys);
/**
* register_pernet_device - register a network namespace device
@@ -398,30 +555,6 @@ int register_pernet_device(struct pernet_operations *ops)
}
EXPORT_SYMBOL_GPL(register_pernet_device);
-int register_pernet_gen_device(int *id, struct pernet_operations *ops)
-{
- int error;
- mutex_lock(&net_mutex);
-again:
- error = ida_get_new_above(&net_generic_ids, 1, id);
- if (error) {
- if (error == -EAGAIN) {
- ida_pre_get(&net_generic_ids, GFP_KERNEL);
- goto again;
- }
- goto out;
- }
- error = register_pernet_operations(&pernet_list, ops);
- if (error)
- ida_remove(&net_generic_ids, *id);
- else if (first_device == &pernet_list)
- first_device = &ops->list;
-out:
- mutex_unlock(&net_mutex);
- return error;
-}
-EXPORT_SYMBOL_GPL(register_pernet_gen_device);
-
/**
* unregister_pernet_device - unregister a network namespace netdevice
* @ops: pernet operations structure to manipulate
@@ -440,60 +573,3 @@ void unregister_pernet_device(struct pernet_operations *ops)
mutex_unlock(&net_mutex);
}
EXPORT_SYMBOL_GPL(unregister_pernet_device);
-
-void unregister_pernet_gen_device(int id, struct pernet_operations *ops)
-{
- mutex_lock(&net_mutex);
- if (&ops->list == first_device)
- first_device = first_device->next;
- unregister_pernet_operations(ops);
- ida_remove(&net_generic_ids, id);
- mutex_unlock(&net_mutex);
-}
-EXPORT_SYMBOL_GPL(unregister_pernet_gen_device);
-
-static void net_generic_release(struct rcu_head *rcu)
-{
- struct net_generic *ng;
-
- ng = container_of(rcu, struct net_generic, rcu);
- kfree(ng);
-}
-
-int net_assign_generic(struct net *net, int id, void *data)
-{
- struct net_generic *ng, *old_ng;
-
- BUG_ON(!mutex_is_locked(&net_mutex));
- BUG_ON(id == 0);
-
- ng = old_ng = net->gen;
- if (old_ng->len >= id)
- goto assign;
-
- ng = kzalloc(sizeof(struct net_generic) +
- id * sizeof(void *), GFP_KERNEL);
- if (ng == NULL)
- return -ENOMEM;
-
- /*
- * Some synchronisation notes:
- *
- * The net_generic explores the net->gen array inside rcu
- * read section. Besides once set the net->gen->ptr[x]
- * pointer never changes (see rules in netns/generic.h).
- *
- * That said, we simply duplicate this array and schedule
- * the old copy for kfree after a grace period.
- */
-
- ng->len = id;
- memcpy(&ng->ptr, &old_ng->ptr, old_ng->len);
-
- rcu_assign_pointer(net->gen, ng);
- call_rcu(&old_ng->rcu, net_generic_release);
-assign:
- ng->ptr[id - 1] = data;
- return 0;
-}
-EXPORT_SYMBOL_GPL(net_assign_generic);