driver core: move device->knode_class to device_private

As the description of struct device_private says, it stores data which
is private to driver core. And it already has similar fields like:
knode_parent, knode_driver, knode_driver and knode_bus. This look it is
more proper to put knode_class together with those fields to make it
private to driver core.

This patch move device->knode_class to device_private to make it comply
with code convention.
Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/base/base.h

@@ -60,6 +60,7 @@ struct driver_private {
  * @knode_parent - node in sibling list
  * @knode_driver - node in driver list
  * @knode_bus - node in bus list
+ * @knode_class - node in class list
  * @deferred_probe - entry in deferred_probe_list which is used to retry the
  *	binding of drivers which were unable to get all the resources needed by
  *	the device; typically because it depends on another driver getting
@@ -74,6 +75,7 @@ struct device_private {
 	struct klist_node knode_parent;
 	struct klist_node knode_driver;
 	struct klist_node knode_bus;
+	struct klist_node knode_class;
 	struct list_head deferred_probe;
 	struct device *device;
 };
@@ -83,6 +85,8 @@ struct device_private {
 	container_of(obj, struct device_private, knode_driver)
 #define to_device_private_bus(obj)	\
 	container_of(obj, struct device_private, knode_bus)
+#define to_device_private_class(obj)	\
+	container_of(obj, struct device_private, knode_class)
 
 /* initialisation functions */
 extern int devices_init(void);

drivers/base/class.c

@@ -117,16 +117,22 @@ static void class_put(struct class *cls)
 		kset_put(&cls->p->subsys);
 }
 
+static struct device *klist_class_to_dev(struct klist_node *n)
+{
+	struct device_private *p = to_device_private_class(n);
+	return p->device;
+}
+
 static void klist_class_dev_get(struct klist_node *n)
 {
-	struct device *dev = container_of(n, struct device, knode_class);
+	struct device *dev = klist_class_to_dev(n);
 
 	get_device(dev);
 }
 
 static void klist_class_dev_put(struct klist_node *n)
 {
-	struct device *dev = container_of(n, struct device, knode_class);
+	struct device *dev = klist_class_to_dev(n);
 
 	put_device(dev);
 }
@@ -277,7 +283,7 @@ void class_dev_iter_init(struct class_dev_iter *iter, struct class *class,
 	struct klist_node *start_knode = NULL;
 
 	if (start)
-		start_knode = &start->knode_class;
+		start_knode = &start->p->knode_class;
 	klist_iter_init_node(&class->p->klist_devices, &iter->ki, start_knode);
 	iter->type = type;
 }
@@ -304,7 +310,7 @@ struct device *class_dev_iter_next(struct class_dev_iter *iter)
 		knode = klist_next(&iter->ki);
 		if (!knode)
 			return NULL;
-		dev = container_of(knode, struct device, knode_class);
+		dev = klist_class_to_dev(knode);
 		if (!iter->type || iter->type == dev->type)
 			return dev;
 	}

drivers/base/core.c

@@ -1966,7 +1966,7 @@ int device_add(struct device *dev)
 	if (dev->class) {
 		mutex_lock(&dev->class->p->mutex);
 		/* tie the class to the device */
-		klist_add_tail(&dev->knode_class,
+		klist_add_tail(&dev->p->knode_class,
 			       &dev->class->p->klist_devices);
 
 		/* notify any interfaces that the device is here */
@@ -2105,7 +2105,7 @@ void device_del(struct device *dev)
 			if (class_intf->remove_dev)
 				class_intf->remove_dev(dev, class_intf);
 		/* remove the device from the class list */
-		klist_del(&dev->knode_class);
+		klist_del(&dev->p->knode_class);
 		mutex_unlock(&dev->class->p->mutex);
 	}
 	device_remove_file(dev, &dev_attr_uevent);

include/linux/device.h

@@ -1035,7 +1035,6 @@ struct device {
 	spinlock_t		devres_lock;
 	struct list_head	devres_head;
 
-	struct klist_node	knode_class;
 	struct class		*class;
 	const struct attribute_group **groups;	/* optional groups */