driver core: create a private portion of struct device

This is to be used to move things out of struct device that no code
outside of the driver core should ever touch.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/base/base.h b/drivers/base/base.h
index ca2b037..62a2cb5 100644 (file)
--- a/drivers/base/base.h
+++ b/drivers/base/base.h
@@ -63,6 +63,18 @@ struct class_private {
 #define to_class(obj)  \
        container_of(obj, struct class_private, class_subsys.kobj)
 
+/**
+ * struct device_private - structure to hold the private to the driver core portions of the device structure.
+ *
+ * @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 device *device;
+};
+
 /* initialisation functions */
 extern int devices_init(void);
 extern int buses_init(void);

diff --git a/drivers/base/core.c b/drivers/base/core.c
index 059966b..16d8599 100644 (file)
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -109,6 +109,7 @@ static struct sysfs_ops dev_sysfs_ops = {
 static void device_release(struct kobject *kobj)
 {
        struct device *dev = to_dev(kobj);
+       struct device_private *p = dev->p;
 
        if (dev->release)
                dev->release(dev);
@@ -120,6 +121,7 @@ static void device_release(struct kobject *kobj)
                WARN(1, KERN_ERR "Device '%s' does not have a release() "
                        "function, it is broken and must be fixed.\n",
                        dev_name(dev));
+       kfree(p);
 }
 
 static struct kobj_type device_ktype = {
@@ -859,6 +861,13 @@ int device_add(struct device *dev)
        if (!dev)
                goto done;
 
+       dev->p = kzalloc(sizeof(*dev->p), GFP_KERNEL);
+       if (!dev->p) {
+               error = -ENOMEM;
+               goto done;
+       }
+       dev->p->device = dev;
+
        /*
         * for statically allocated devices, which should all be converted
         * some day, we need to initialize the name. We prevent reading back

diff --git a/include/linux/device.h b/include/linux/device.h
index c56b154..4cf063f 100644 (file)
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -28,6 +28,7 @@
 #define BUS_ID_SIZE            20
 
 struct device;
+struct device_private;
 struct device_driver;
 struct driver_private;
 struct class;
@@ -373,6 +374,8 @@ struct device {
        struct klist_node       knode_bus;
        struct device           *parent;
 
+       struct device_private   *p;
+
        struct kobject kobj;
        unsigned                uevent_suppress:1;
        const char              *init_name; /* initial name of the device */