[PATCH 44/61] driver core: create a private portion of struct device

Greg Kroah-Hartman
2009-03-25T00:46:14Z

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>
---
drivers/base/base.h | 12 ++++++++++++
drivers/base/core.c | 9 +++++++++
include/linux/device.h | 3 +++
3 files changed, 24 insertions(+), 0 deletions(-)

diff --git a/drivers/base/base.h b/drivers/base/base.h
index ca2b037..62a2cb5 100644
--- 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
--- 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
--- 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 */
--
1.6.2