#include <linux/list.h>
#include <linux/delay.h>
#include <linux/sched.h>
+#include <linux/idr.h>
#include <net/net_namespace.h>
+#include <net/netns/generic.h>
/*
* Our network namespace constructor/destructor lists
static struct list_head *first_device = &pernet_list;
static DEFINE_MUTEX(net_mutex);
-static DEFINE_MUTEX(net_list_mutex);
LIST_HEAD(net_namespace_list);
-static struct kmem_cache *net_cachep;
-
struct net init_net;
-EXPORT_SYMBOL_GPL(init_net);
-
-void net_lock(void)
-{
- mutex_lock(&net_list_mutex);
-}
-
-void net_unlock(void)
-{
- mutex_unlock(&net_list_mutex);
-}
-
-static struct net *net_alloc(void)
-{
- return kmem_cache_alloc(net_cachep, GFP_KERNEL);
-}
-
-static void net_free(struct net *net)
-{
- if (!net)
- return;
-
- if (unlikely(atomic_read(&net->use_count) != 0)) {
- printk(KERN_EMERG "network namespace not free! Usage: %d\n",
- atomic_read(&net->use_count));
- return;
- }
-
- kmem_cache_free(net_cachep, net);
-}
-
-static void cleanup_net(struct work_struct *work)
-{
- struct pernet_operations *ops;
- struct net *net;
-
- net = container_of(work, struct net, work);
-
- mutex_lock(&net_mutex);
-
- /* Don't let anyone else find us. */
- net_lock();
- list_del(&net->list);
- net_unlock();
-
- /* Run all of the network namespace exit methods */
- list_for_each_entry_reverse(ops, &pernet_list, list) {
- if (ops->exit)
- ops->exit(net);
- }
-
- mutex_unlock(&net_mutex);
-
- /* Ensure there are no outstanding rcu callbacks using this
- * network namespace.
- */
- rcu_barrier();
-
- /* Finally it is safe to free my network namespace structure */
- net_free(net);
-}
-
+EXPORT_SYMBOL(init_net);
-void __put_net(struct net *net)
-{
- /* Cleanup the network namespace in process context */
- INIT_WORK(&net->work, cleanup_net);
- schedule_work(&net->work);
-}
-EXPORT_SYMBOL_GPL(__put_net);
+#define INITIAL_NET_GEN_PTRS 13 /* +1 for len +2 for rcu_head */
/*
* setup_net runs the initializers for the network namespace object.
*/
-static int setup_net(struct net *net)
+static __net_init int setup_net(struct net *net)
{
/* Must be called with net_mutex held */
struct pernet_operations *ops;
int error;
+ struct net_generic *ng;
- memset(net, 0, sizeof(struct net));
atomic_set(&net->count, 1);
atomic_set(&net->use_count, 0);
+ error = -ENOMEM;
+ ng = kzalloc(sizeof(struct net_generic) +
+ INITIAL_NET_GEN_PTRS * sizeof(void *), GFP_KERNEL);
+ if (ng == NULL)
+ goto out;
+
+ ng->len = INITIAL_NET_GEN_PTRS;
+ INIT_RCU_HEAD(&ng->rcu);
+ rcu_assign_pointer(net->gen, ng);
+
error = 0;
list_for_each_entry(ops, &pernet_list, list) {
if (ops->init) {
if (ops->exit)
ops->exit(net);
}
+
+ rcu_barrier();
+ kfree(ng);
goto out;
}
+#ifdef CONFIG_NET_NS
+static struct kmem_cache *net_cachep;
+static struct workqueue_struct *netns_wq;
+
+static struct net *net_alloc(void)
+{
+ return kmem_cache_zalloc(net_cachep, GFP_KERNEL);
+}
+
+static void net_free(struct net *net)
+{
+ if (!net)
+ return;
+
+ if (unlikely(atomic_read(&net->use_count) != 0)) {
+ printk(KERN_EMERG "network namespace not free! Usage: %d\n",
+ atomic_read(&net->use_count));
+ return;
+ }
+
+ kmem_cache_free(net_cachep, net);
+}
+
struct net *copy_net_ns(unsigned long flags, struct net *old_net)
{
struct net *new_net = NULL;
if (!(flags & CLONE_NEWNET))
return old_net;
-#ifndef CONFIG_NET_NS
- return ERR_PTR(-EINVAL);
-#endif
-
err = -ENOMEM;
new_net = net_alloc();
if (!new_net)
if (err)
goto out_unlock;
- net_lock();
+ rtnl_lock();
list_add_tail(&new_net->list, &net_namespace_list);
- net_unlock();
+ rtnl_unlock();
out_unlock:
return new_net;
}
+static void cleanup_net(struct work_struct *work)
+{
+ struct pernet_operations *ops;
+ struct net *net;
+
+ net = container_of(work, struct net, work);
+
+ mutex_lock(&net_mutex);
+
+ /* Don't let anyone else find us. */
+ rtnl_lock();
+ list_del(&net->list);
+ rtnl_unlock();
+
+ /* Run all of the network namespace exit methods */
+ list_for_each_entry_reverse(ops, &pernet_list, list) {
+ if (ops->exit)
+ ops->exit(net);
+ }
+
+ mutex_unlock(&net_mutex);
+
+ /* Ensure there are no outstanding rcu callbacks using this
+ * network namespace.
+ */
+ rcu_barrier();
+
+ /* Finally it is safe to free my network namespace structure */
+ net_free(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);
+}
+EXPORT_SYMBOL_GPL(__put_net);
+
+#else
+struct net *copy_net_ns(unsigned long flags, struct net *old_net)
+{
+ if (flags & CLONE_NEWNET)
+ return ERR_PTR(-EINVAL);
+ return old_net;
+}
+#endif
+
static int __init net_ns_init(void)
{
int err;
printk(KERN_INFO "net_namespace: %zd bytes\n", sizeof(struct net));
+#ifdef CONFIG_NET_NS
net_cachep = kmem_cache_create("net_namespace", sizeof(struct net),
SMP_CACHE_BYTES,
SLAB_PANIC, NULL);
+
+ /* Create workqueue for cleanup */
+ netns_wq = create_singlethread_workqueue("netns");
+ if (!netns_wq)
+ panic("Could not create netns workq");
+#endif
+
mutex_lock(&net_mutex);
err = setup_net(&init_net);
- net_lock();
+ rtnl_lock();
list_add_tail(&init_net.list, &net_namespace_list);
- net_unlock();
+ rtnl_unlock();
mutex_unlock(&net_mutex);
if (err)
pure_initcall(net_ns_init);
+#ifdef CONFIG_NET_NS
static int register_pernet_operations(struct list_head *list,
struct pernet_operations *ops)
{
struct net *net, *undo_net;
int error;
- error = 0;
list_add_tail(&ops->list, list);
- for_each_net(net) {
- if (ops->init) {
+ if (ops->init) {
+ for_each_net(net) {
error = ops->init(net);
if (error)
goto out_undo;
}
}
-out:
- return error;
+ return 0;
out_undo:
/* If I have an error cleanup all namespaces I initialized */
list_del(&ops->list);
- for_each_net(undo_net) {
- if (undo_net == net)
- goto undone;
- if (ops->exit)
+ if (ops->exit) {
+ for_each_net(undo_net) {
+ if (undo_net == net)
+ goto undone;
ops->exit(undo_net);
+ }
}
undone:
- goto out;
+ return error;
}
static void unregister_pernet_operations(struct pernet_operations *ops)
struct net *net;
list_del(&ops->list);
- for_each_net(net)
- if (ops->exit)
+ if (ops->exit)
+ for_each_net(net)
ops->exit(net);
}
+#else
+
+static int register_pernet_operations(struct list_head *list,
+ struct pernet_operations *ops)
+{
+ if (ops->init == NULL)
+ return 0;
+ return ops->init(&init_net);
+}
+
+static void unregister_pernet_operations(struct pernet_operations *ops)
+{
+ if (ops->exit)
+ ops->exit(&init_net);
+}
+#endif
+
+static DEFINE_IDA(net_generic_ids);
+
/**
* register_pernet_subsys - register a network namespace subsystem
* @ops: pernet operations structure for the subsystem
* @ops: pernet operations structure to manipulate
*
* Remove the pernet operations structure from the list to be
- * used when network namespaces are created or destoryed. In
+ * used when network namespaces are created or destroyed. In
* addition run the exit method for all existing network
* namespaces.
*/
}
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
*
* Remove the pernet operations structure from the list to be
- * used when network namespaces are created or destoryed. In
+ * used when network namespaces are created or destroyed. In
* addition run the exit method for all existing network
* namespaces.
*/
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;
+ INIT_RCU_HEAD(&ng->rcu);
+ 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);
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff