Revert "driver core: move klist_children into private structure"

This reverts commit 11c3b5c3e0.

Turns out that device_initialize shouldn't fail silently.
This series needs to be reworked in order to get into proper
shape.

Reported-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/base/base.h

@@ -66,20 +66,14 @@ struct class_private {
 /**
  * struct device_private - structure to hold the private to the driver core portions of the device structure.
  *
- * @klist_children - klist containing all children of this device
- * @knode_parent - node in sibling list
  * @device - pointer back to the struct class that this structure is
  * associated with.
  *
  * Nothing outside of the driver core should ever touch these fields.
  */
 struct device_private {
-	struct klist klist_children;
-	struct klist_node knode_parent;
 	struct device *device;
 };
-#define to_device_private_parent(obj)	\
-	container_of(obj, struct device_private, knode_parent)
 
 /* initialisation functions */
 extern int devices_init(void);

drivers/base/core.c

@@ -509,16 +509,14 @@ EXPORT_SYMBOL_GPL(device_schedule_callback_owner);
 
 static void klist_children_get(struct klist_node *n)
 {
-	struct device_private *p = to_device_private_parent(n);
-	struct device *dev = p->device;
+	struct device *dev = container_of(n, struct device, knode_parent);
 
 	get_device(dev);
 }
 
 static void klist_children_put(struct klist_node *n)
 {
-	struct device_private *p = to_device_private_parent(n);
-	struct device *dev = p->device;
+	struct device *dev = container_of(n, struct device, knode_parent);
 
 	put_device(dev);
 }
@@ -548,7 +546,7 @@ void device_initialize(struct device *dev)
 	dev->p->device = dev;
 	dev->kobj.kset = devices_kset;
 	kobject_init(&dev->kobj, &device_ktype);
-	klist_init(&dev->p->klist_children, klist_children_get,
+	klist_init(&dev->klist_children, klist_children_get,
 		   klist_children_put);
 	INIT_LIST_HEAD(&dev->dma_pools);
 	init_MUTEX(&dev->sem);
@@ -932,8 +930,7 @@ int device_add(struct device *dev)
 	kobject_uevent(&dev->kobj, KOBJ_ADD);
 	bus_attach_device(dev);
 	if (parent)
-		klist_add_tail(&dev->p->knode_parent,
-			       &parent->p->klist_children);
+		klist_add_tail(&dev->knode_parent, &parent->klist_children);
 
 	if (dev->class) {
 		mutex_lock(&dev->class->p->class_mutex);
@@ -1047,7 +1044,7 @@ void device_del(struct device *dev)
 	device_pm_remove(dev);
 	dpm_sysfs_remove(dev);
 	if (parent)
-		klist_del(&dev->p->knode_parent);
+		klist_del(&dev->knode_parent);
 	if (MAJOR(dev->devt)) {
 		device_remove_sys_dev_entry(dev);
 		device_remove_file(dev, &devt_attr);
@@ -1108,14 +1105,7 @@ void device_unregister(struct device *dev)
 static struct device *next_device(struct klist_iter *i)
 {
 	struct klist_node *n = klist_next(i);
-	struct device *dev = NULL;
-	struct device_private *p;
-
-	if (n) {
-		p = to_device_private_parent(n);
-		dev = p->device;
-	}
-	return dev;
+	return n ? container_of(n, struct device, knode_parent) : NULL;
 }
 
 /**
@@ -1137,7 +1127,7 @@ int device_for_each_child(struct device *parent, void *data,
 	struct device *child;
 	int error = 0;
 
-	klist_iter_init(&parent->p->klist_children, &i);
+	klist_iter_init(&parent->klist_children, &i);
 	while ((child = next_device(&i)) && !error)
 		error = fn(child, data);
 	klist_iter_exit(&i);
@@ -1168,7 +1158,7 @@ struct device *device_find_child(struct device *parent, void *data,
 	if (!parent)
 		return NULL;
 
-	klist_iter_init(&parent->p->klist_children, &i);
+	klist_iter_init(&parent->klist_children, &i);
 	while ((child = next_device(&i)))
 		if (match(child, data) && get_device(child))
 			break;
@@ -1582,10 +1572,9 @@ int device_move(struct device *dev, struct device *new_parent)
 	old_parent = dev->parent;
 	dev->parent = new_parent;
 	if (old_parent)
-		klist_remove(&dev->p->knode_parent);
+		klist_remove(&dev->knode_parent);
 	if (new_parent) {
-		klist_add_tail(&dev->p->knode_parent,
-			       &new_parent->p->klist_children);
+		klist_add_tail(&dev->knode_parent, &new_parent->klist_children);
 		set_dev_node(dev, dev_to_node(new_parent));
 	}
 
@@ -1597,11 +1586,11 @@ int device_move(struct device *dev, struct device *new_parent)
 		device_move_class_links(dev, new_parent, old_parent);
 		if (!kobject_move(&dev->kobj, &old_parent->kobj)) {
 			if (new_parent)
-				klist_remove(&dev->p->knode_parent);
+				klist_remove(&dev->knode_parent);
 			dev->parent = old_parent;
 			if (old_parent) {
-				klist_add_tail(&dev->p->knode_parent,
-					       &old_parent->p->klist_children);
+				klist_add_tail(&dev->knode_parent,
+					       &old_parent->klist_children);
 				set_dev_node(dev, dev_to_node(old_parent));
 			}
 		}

include/linux/device.h

@@ -366,6 +366,8 @@ struct device_dma_parameters {
 };
 
 struct device {
+	struct klist		klist_children;
+	struct klist_node	knode_parent;	/* node in sibling list */
 	struct klist_node	knode_driver;
 	struct klist_node	knode_bus;
 	struct device		*parent;