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>
diff --git a/drivers/base/class.c b/drivers/base/class.c
index 9c6a0d6..8e231d0 100644
--- a/drivers/base/class.c
+++ b/drivers/base/class.c
@@ -63,6 +63,14 @@
kfree(cp);
}
+static const struct kobj_ns_type_operations *class_child_ns_type(struct kobject *kobj)
+{
+ struct class_private *cp = to_class(kobj);
+ struct class *class = cp->class;
+
+ return class->ns_type;
+}
+
static const struct sysfs_ops class_sysfs_ops = {
.show = class_attr_show,
.store = class_attr_store,
@@ -71,6 +79,7 @@
static struct kobj_type class_ktype = {
.sysfs_ops = &class_sysfs_ops,
.release = class_release,
+ .child_ns_type = class_child_ns_type,
};
/* Hotplug events for classes go to the class class_subsys */
diff --git a/drivers/base/core.c b/drivers/base/core.c
index 356dd01..f069991 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -131,9 +131,21 @@
kfree(p);
}
+static const void *device_namespace(struct kobject *kobj)
+{
+ struct device *dev = to_dev(kobj);
+ const void *ns = NULL;
+
+ if (dev->class && dev->class->ns_type)
+ ns = dev->class->namespace(dev);
+
+ return ns;
+}
+
static struct kobj_type device_ktype = {
.release = device_release,
.sysfs_ops = &dev_sysfs_ops,
+ .namespace = device_namespace,
};
@@ -595,11 +607,59 @@
return virtual_dir;
}
+struct class_dir {
+ struct kobject kobj;
+ struct class *class;
+};
+
+#define to_class_dir(obj) container_of(obj, struct class_dir, kobj)
+
+static void class_dir_release(struct kobject *kobj)
+{
+ struct class_dir *dir = to_class_dir(kobj);
+ kfree(dir);
+}
+
+static const
+struct kobj_ns_type_operations *class_dir_child_ns_type(struct kobject *kobj)
+{
+ struct class_dir *dir = to_class_dir(kobj);
+ return dir->class->ns_type;
+}
+
+static struct kobj_type class_dir_ktype = {
+ .release = class_dir_release,
+ .sysfs_ops = &kobj_sysfs_ops,
+ .child_ns_type = class_dir_child_ns_type
+};
+
+static struct kobject *
+class_dir_create_and_add(struct class *class, struct kobject *parent_kobj)
+{
+ struct class_dir *dir;
+ int retval;
+
+ dir = kzalloc(sizeof(*dir), GFP_KERNEL);
+ if (!dir)
+ return NULL;
+
+ dir->class = class;
+ kobject_init(&dir->kobj, &class_dir_ktype);
+
+ dir->kobj.kset = &class->p->class_dirs;
+
+ retval = kobject_add(&dir->kobj, parent_kobj, "%s", class->name);
+ if (retval < 0) {
+ kobject_put(&dir->kobj);
+ return NULL;
+ }
+ return &dir->kobj;
+}
+
+
static struct kobject *get_device_parent(struct device *dev,
struct device *parent)
{
- int retval;
-
if (dev->class) {
static DEFINE_MUTEX(gdp_mutex);
struct kobject *kobj = NULL;
@@ -634,18 +694,7 @@
}
/* or create a new class-directory at the parent device */
- k = kobject_create();
- if (!k) {
- mutex_unlock(&gdp_mutex);
- return NULL;
- }
- k->kset = &dev->class->p->class_dirs;
- retval = kobject_add(k, parent_kobj, "%s", dev->class->name);
- if (retval < 0) {
- mutex_unlock(&gdp_mutex);
- kobject_put(k);
- return NULL;
- }
+ k = class_dir_create_and_add(dev->class, parent_kobj);
/* do not emit an uevent for this simple "glue" directory */
mutex_unlock(&gdp_mutex);
return k;
diff --git a/include/linux/device.h b/include/linux/device.h
index 6f96191..7bb9f42 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -202,6 +202,9 @@
int (*suspend)(struct device *dev, pm_message_t state);
int (*resume)(struct device *dev);
+ const struct kobj_ns_type_operations *ns_type;
+ const void *(*namespace)(struct device *dev);
+
const struct dev_pm_ops *pm;
struct class_private *p;
diff --git a/include/linux/kobject.h b/include/linux/kobject.h
index 3950d3c..d9456f6 100644
--- a/include/linux/kobject.h
+++ b/include/linux/kobject.h
@@ -108,6 +108,8 @@
void (*release)(struct kobject *kobj);
const struct sysfs_ops *sysfs_ops;
struct attribute **default_attrs;
+ const struct kobj_ns_type_operations *(*child_ns_type)(struct kobject *kobj);
+ const void *(*namespace)(struct kobject *kobj);
};
struct kobj_uevent_env {
@@ -134,6 +136,30 @@
extern const struct sysfs_ops kobj_sysfs_ops;
+enum kobj_ns_type {
+ KOBJ_NS_TYPE_NONE = 0,
+ KOBJ_NS_TYPES
+};
+
+struct sock;
+struct kobj_ns_type_operations {
+ enum kobj_ns_type type;
+ const void *(*current_ns)(void);
+ const void *(*netlink_ns)(struct sock *sk);
+ const void *(*initial_ns)(void);
+};
+
+int kobj_ns_type_register(const struct kobj_ns_type_operations *ops);
+int kobj_ns_type_registered(enum kobj_ns_type type);
+const struct kobj_ns_type_operations *kobj_child_ns_ops(struct kobject *parent);
+const struct kobj_ns_type_operations *kobj_ns_ops(struct kobject *kobj);
+
+const void *kobj_ns_current(enum kobj_ns_type type);
+const void *kobj_ns_netlink(enum kobj_ns_type type, struct sock *sk);
+const void *kobj_ns_initial(enum kobj_ns_type type);
+void kobj_ns_exit(enum kobj_ns_type type, const void *ns);
+
+
/**
* struct kset - a set of kobjects of a specific type, belonging to a specific subsystem.
*
diff --git a/lib/kobject.c b/lib/kobject.c
index 8115eb1..bbb2bb4 100644
--- a/lib/kobject.c
+++ b/lib/kobject.c
@@ -850,6 +850,109 @@
}
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);
