kobj: Add basic infrastructure for dealing with namespaces.

Move complete knowledge of namespaces into the kobject layer
so we can use that information when reporting kobjects to
userspace.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Eric W. Biederman 2010-03-30 11:31:25 -07:00 committed by Greg Kroah-Hartman
parent ba514a57f5
commit bc451f2058
5 changed files with 204 additions and 14 deletions

View file

@ -850,6 +850,109 @@ struct kset *kset_create_and_add(const char *name,
}
EXPORT_SYMBOL_GPL(kset_create_and_add);
static DEFINE_SPINLOCK(kobj_ns_type_lock);
static const struct kobj_ns_type_operations *kobj_ns_ops_tbl[KOBJ_NS_TYPES];
int kobj_ns_type_register(const struct kobj_ns_type_operations *ops)
{
enum kobj_ns_type type = ops->type;
int error;
spin_lock(&kobj_ns_type_lock);
error = -EINVAL;
if (type >= KOBJ_NS_TYPES)
goto out;
error = -EINVAL;
if (type <= KOBJ_NS_TYPE_NONE)
goto out;
error = -EBUSY;
if (kobj_ns_ops_tbl[type])
goto out;
error = 0;
kobj_ns_ops_tbl[type] = ops;
out:
spin_unlock(&kobj_ns_type_lock);
return error;
}
int kobj_ns_type_registered(enum kobj_ns_type type)
{
int registered = 0;
spin_lock(&kobj_ns_type_lock);
if ((type > KOBJ_NS_TYPE_NONE) && (type < KOBJ_NS_TYPES))
registered = kobj_ns_ops_tbl[type] != NULL;
spin_unlock(&kobj_ns_type_lock);
return registered;
}
const struct kobj_ns_type_operations *kobj_child_ns_ops(struct kobject *parent)
{
const struct kobj_ns_type_operations *ops = NULL;
if (parent && parent->ktype->child_ns_type)
ops = parent->ktype->child_ns_type(parent);
return ops;
}
const struct kobj_ns_type_operations *kobj_ns_ops(struct kobject *kobj)
{
return kobj_child_ns_ops(kobj->parent);
}
const void *kobj_ns_current(enum kobj_ns_type type)
{
const void *ns = NULL;
spin_lock(&kobj_ns_type_lock);
if ((type > KOBJ_NS_TYPE_NONE) && (type < KOBJ_NS_TYPES) &&
kobj_ns_ops_tbl[type])
ns = kobj_ns_ops_tbl[type]->current_ns();
spin_unlock(&kobj_ns_type_lock);
return ns;
}
const void *kobj_ns_netlink(enum kobj_ns_type type, struct sock *sk)
{
const void *ns = NULL;
spin_lock(&kobj_ns_type_lock);
if ((type > KOBJ_NS_TYPE_NONE) && (type < KOBJ_NS_TYPES) &&
kobj_ns_ops_tbl[type])
ns = kobj_ns_ops_tbl[type]->netlink_ns(sk);
spin_unlock(&kobj_ns_type_lock);
return ns;
}
const void *kobj_ns_initial(enum kobj_ns_type type)
{
const void *ns = NULL;
spin_lock(&kobj_ns_type_lock);
if ((type > KOBJ_NS_TYPE_NONE) && (type < KOBJ_NS_TYPES) &&
kobj_ns_ops_tbl[type])
ns = kobj_ns_ops_tbl[type]->initial_ns();
spin_unlock(&kobj_ns_type_lock);
return ns;
}
void kobj_ns_exit(enum kobj_ns_type type, const void *ns)
{
}
EXPORT_SYMBOL(kobject_get);
EXPORT_SYMBOL(kobject_put);
EXPORT_SYMBOL(kobject_del);