[PATCH 151/196] Driver core: move the static kobject out of struct driver

Greg Kroah-Hartman
2008-01-25T08:34:11Z

This patch removes the kobject, and a few other driver-core-only fields
out of struct driver and into the driver core only. Now drivers can be
safely create on the stack or statically (like they currently are.)

Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---
drivers/base/base.h | 8 +++++
drivers/base/bus.c | 71 +++++++++++++++++++++++++---------------------
drivers/base/dd.c | 24 ++++++++--------
drivers/base/driver.c | 40 +++++++++++++++++---------
drivers/base/module.c | 12 ++++----
drivers/base/platform.c | 2 +-
include/linux/device.h | 16 ++++------
7 files changed, 99 insertions(+), 74 deletions(-)

diff --git a/drivers/base/base.h b/drivers/base/base.h
index 0547236..3b0f395 100644
--- a/drivers/base/base.h
+++ b/drivers/base/base.h
@@ -27,6 +27,14 @@ struct bus_type_private {
struct bus_type *bus;
};

+struct driver_private {
+ struct kobject kobj;
+ struct klist klist_devices;
+ struct klist_node knode_bus;
+ struct module_kobject *mkobj;
+ struct device_driver *driver;
+};
+#define to_driver(obj) container_of(obj, struct driver_private, kobj)

/* initialisation functions */
extern int devices_init(void);
diff --git a/drivers/base/bus.c b/drivers/base/bus.c
index 04d3850..aa0c986 100644
--- a/drivers/base/bus.c
+++ b/drivers/base/bus.c
@@ -3,6 +3,8 @@
*
* Copyright (c) 2002-3 Patrick Mochel
* Copyright (c) 2002-3 Open Source Development Labs
+ * Copyright (c) 2007 Greg Kroah-Hartman <gregkh@suse.de>
+ * Copyright (c) 2007 Novell Inc.
*
* This file is released under the GPLv2
*
@@ -24,7 +26,6 @@
*/

#define to_drv_attr(_attr) container_of(_attr, struct driver_attribute, attr)
-#define to_driver(obj) container_of(obj, struct device_driver, kobj)

static int __must_check bus_rescan_devices_helper(struct device *dev,
@@ -49,11 +50,11 @@ static ssize_t
drv_attr_show(struct kobject * kobj, struct attribute * attr, char * buf)
{
struct driver_attribute * drv_attr = to_drv_attr(attr);
- struct device_driver * drv = to_driver(kobj);
+ struct driver_private *drv_priv = to_driver(kobj);
ssize_t ret = -EIO;

if (drv_attr->show)
- ret = drv_attr->show(drv, buf);
+ ret = drv_attr->show(drv_priv->driver, buf);
return ret;
}

@@ -62,11 +63,11 @@ drv_attr_store(struct kobject * kobj, struct attribute * attr,
const char * buf, size_t count)
{
struct driver_attribute * drv_attr = to_drv_attr(attr);
- struct device_driver * drv = to_driver(kobj);
+ struct driver_private *drv_priv = to_driver(kobj);
ssize_t ret = -EIO;

if (drv_attr->store)
- ret = drv_attr->store(drv, buf, count);
+ ret = drv_attr->store(drv_priv->driver, buf, count);
return ret;
}

@@ -75,22 +76,12 @@ static struct sysfs_ops driver_sysfs_ops = {
.store = drv_attr_store,
};

-
-static void driver_release(struct kobject * kobj)
+static void driver_release(struct kobject *kobj)
{
- /*
- * Yes this is an empty release function, it is this way because struct
- * device is always a static object, not a dynamic one. Yes, this is
- * not nice and bad, but remember, drivers are code, reference counted
- * by the module count, not a device, which is really data. And yes,
- * in the future I do want to have all drivers be created dynamically,
- * and am working toward that goal, but it will take a bit longer...
- *
- * But do not let this example give _anyone_ the idea that they can
- * create a release function without any code in it at all, to do that
- * is almost always wrong. If you have any questions about this,
- * please send an email to <greg@kroah.com>
- */
+ struct driver_private *drv_priv = to_driver(kobj);
+
+ pr_debug("%s: freeing %s\n", __FUNCTION__, kobject_name(kobj));
+ kfree(drv_priv);
}

static struct kobj_type driver_ktype = {
@@ -350,7 +341,13 @@ struct device * bus_find_device(struct bus_type *bus,
static struct device_driver * next_driver(struct klist_iter * i)
{
struct klist_node * n = klist_next(i);
- return n ? container_of(n, struct device_driver, knode_bus) : NULL;
+ struct driver_private *drv_priv;
+
+ if (n) {
+ drv_priv = container_of(n, struct driver_private, knode_bus);
+ return drv_priv->driver;
+ }
+ return NULL;
}

/**
@@ -384,7 +381,7 @@ int bus_for_each_drv(struct bus_type * bus, struct device_driver * start,
return -EINVAL;

klist_iter_init_node(&bus->p->klist_drivers, &i,
- start ? &start->knode_bus : NULL);
+ start ? &start->p->knode_bus : NULL);
while ((drv = next_driver(&i)) && !error)
error = fn(drv, data);
klist_iter_exit(&i);
@@ -620,7 +617,7 @@ static ssize_t driver_uevent_store(struct device_driver *drv,
enum kobject_action action;

if (kobject_action_type(buf, count, &action) == 0)
- kobject_uevent(&drv->kobj, action);
+ kobject_uevent(&drv->p->kobj, action);
return count;
}
static DRIVER_ATTR(uevent, S_IWUSR, NULL, driver_uevent_store);
@@ -632,19 +629,29 @@ static DRIVER_ATTR(uevent, S_IWUSR, NULL, driver_uevent_store);
*/
int bus_add_driver(struct device_driver *drv)
{
- struct bus_type * bus = bus_get(drv->bus);
+ struct bus_type *bus;
+ struct driver_private *priv;
int error = 0;

+ bus = bus_get(drv->bus);
if (!bus)
return -EINVAL;

pr_debug("bus %s: add driver %s\n", bus->name, drv->name);
- error = kobject_set_name(&drv->kobj, "%s", drv->name);
+
+ priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ error = kobject_set_name(&priv->kobj, "%s", drv->name);
if (error)
goto out_put_bus;
- drv->kobj.kset = bus->p->drivers_kset;
- drv->kobj.ktype = &driver_ktype;
- error = kobject_register(&drv->kobj);
+ priv->kobj.kset = bus->p->drivers_kset;
+ priv->kobj.ktype = &driver_ktype;
+ klist_init(&priv->klist_devices, NULL, NULL);
+ priv->driver = drv;
+ drv->p = priv;
+ error = kobject_register(&priv->kobj);
if (error)
goto out_put_bus;

@@ -653,7 +660,7 @@ int bus_add_driver(struct device_driver *drv)
if (error)
goto out_unregister;
}
- klist_add_tail(&drv->knode_bus, &bus->p->klist_drivers);
+ klist_add_tail(&priv->knode_bus, &bus->p->klist_drivers);
module_add_driver(drv->owner, drv);

error = driver_create_file(drv, &driver_attr_uevent);
@@ -676,7 +683,7 @@ int bus_add_driver(struct device_driver *drv)

return error;
out_unregister:
- kobject_unregister(&drv->kobj);
+ kobject_unregister(&priv->kobj);
out_put_bus:
bus_put(bus);
return error;
@@ -699,11 +706,11 @@ void bus_remove_driver(struct device_driver * drv)
remove_bind_files(drv);
driver_remove_attrs(drv->bus, drv);
driver_remove_file(drv, &driver_attr_uevent);
- klist_remove(&drv->knode_bus);
+ klist_remove(&drv->p->knode_bus);
pr_debug("bus %s: remove driver %s\n", drv->bus->name, drv->name);
driver_detach(drv);
module_remove_driver(drv);
- kobject_unregister(&drv->kobj);
+ kobject_unregister(&drv->p->kobj);
bus_put(drv->bus);
}

diff --git a/drivers/base/dd.c b/drivers/base/dd.c
index 7bf0e67..87a348c 100644
--- a/drivers/base/dd.c
+++ b/drivers/base/dd.c
@@ -11,6 +11,8 @@
*
* Copyright (c) 2002-5 Patrick Mochel
* Copyright (c) 2002-3 Open Source Development Labs
+ * Copyright (c) 2007 Greg Kroah-Hartman <gregkh@suse.de>
+ * Copyright (c) 2007 Novell Inc.
*
* This file is released under the GPLv2
*/
@@ -23,8 +25,6 @@
#include "base.h"
#include "power/power.h"

-#define to_drv(node) container_of(node, struct device_driver, kobj.entry)
-

static void driver_bound(struct device *dev)
{
@@ -41,20 +41,20 @@ static void driver_bound(struct device *dev)
blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
BUS_NOTIFY_BOUND_DRIVER, dev);

- klist_add_tail(&dev->knode_driver, &dev->driver->klist_devices);
+ klist_add_tail(&dev->knode_driver, &dev->driver->p->klist_devices);
}

static int driver_sysfs_add(struct device *dev)
{
int ret;

- ret = sysfs_create_link(&dev->driver->kobj, &dev->kobj,
+ ret = sysfs_create_link(&dev->driver->p->kobj, &dev->kobj,
kobject_name(&dev->kobj));
if (ret == 0) {
- ret = sysfs_create_link(&dev->kobj, &dev->driver->kobj,
+ ret = sysfs_create_link(&dev->kobj, &dev->driver->p->kobj,
"driver");
if (ret)
- sysfs_remove_link(&dev->driver->kobj,
+ sysfs_remove_link(&dev->driver->p->kobj,
kobject_name(&dev->kobj));
}
return ret;
@@ -65,7 +65,7 @@ static void driver_sysfs_remove(struct device *dev)
struct device_driver *drv = dev->driver;

if (drv) {
- sysfs_remove_link(&drv->kobj, kobject_name(&dev->kobj));
+ sysfs_remove_link(&drv->p->kobj, kobject_name(&dev->kobj));
sysfs_remove_link(&dev->kobj, "driver");
}
}
@@ -339,15 +339,15 @@ void driver_detach(struct device_driver * drv)
struct device * dev;

for (;;) {
- spin_lock(&drv->klist_devices.k_lock);
- if (list_empty(&drv->klist_devices.k_list)) {
- spin_unlock(&drv->klist_devices.k_lock);
+ spin_lock(&drv->p->klist_devices.k_lock);
+ if (list_empty(&drv->p->klist_devices.k_list)) {
+ spin_unlock(&drv->p->klist_devices.k_lock);
break;
}
- dev = list_entry(drv->klist_devices.k_list.prev,
+ dev = list_entry(drv->p->klist_devices.k_list.prev,
struct device, knode_driver.n_node);
get_device(dev);
- spin_unlock(&drv->klist_devices.k_lock);
+ spin_unlock(&drv->p->klist_devices.k_lock);

if (dev->parent) /* Needed for USB */
down(&dev->parent->sem);
diff --git a/drivers/base/driver.c b/drivers/base/driver.c
index 633ae1d..5aacff2 100644
--- a/drivers/base/driver.c
+++ b/drivers/base/driver.c
@@ -3,6 +3,8 @@
*
* Copyright (c) 2002-3 Patrick Mochel
* Copyright (c) 2002-3 Open Source Development Labs
+ * Copyright (c) 2007 Greg Kroah-Hartman <gregkh@suse.de>
+ * Copyright (c) 2007 Novell Inc.
*
* This file is released under the GPLv2
*
@@ -15,7 +17,6 @@
#include "base.h"

#define to_dev(node) container_of(node, struct device, driver_list)
-#define to_drv(obj) container_of(obj, struct device_driver, kobj)

static struct device * next_device(struct klist_iter * i)
@@ -44,7 +45,7 @@ int driver_for_each_device(struct device_driver * drv, struct device * start,
if (!drv)
return -EINVAL;

- klist_iter_init_node(&drv->klist_devices, &i,
+ klist_iter_init_node(&drv->p->klist_devices, &i,
start ? &start->knode_driver : NULL);
while ((dev = next_device(&i)) && !error)
error = fn(dev, data);
@@ -80,7 +81,7 @@ struct device * driver_find_device(struct device_driver *drv,
if (!drv)
return NULL;

- klist_iter_init_node(&drv->klist_devices, &i,
+ klist_iter_init_node(&drv->p->klist_devices, &i,
(start ? &start->knode_driver : NULL));
while ((dev = next_device(&i)))
if (match(dev, data) && get_device(dev))
@@ -100,7 +101,7 @@ int driver_create_file(struct device_driver * drv, struct driver_attribute * att
{
int error;
if (get_driver(drv)) {
- error = sysfs_create_file(&drv->kobj, &attr->attr);
+ error = sysfs_create_file(&drv->p->kobj, &attr->attr);
put_driver(drv);
} else
error = -EINVAL;
@@ -117,7 +118,7 @@ int driver_create_file(struct device_driver * drv, struct driver_attribute * att
void driver_remove_file(struct device_driver * drv, struct driver_attribute * attr)
{
if (get_driver(drv)) {
- sysfs_remove_file(&drv->kobj, &attr->attr);
+ sysfs_remove_file(&drv->p->kobj, &attr->attr);
put_driver(drv);
}
}
@@ -143,7 +144,7 @@ int driver_add_kobj(struct device_driver *drv, struct kobject *kobj,
if (!name)
return -ENOMEM;

- return kobject_add_ng(kobj, &drv->kobj, "%s", name);
+ return kobject_add_ng(kobj, &drv->p->kobj, "%s", name);
}
EXPORT_SYMBOL_GPL(driver_add_kobj);

@@ -153,7 +154,15 @@ EXPORT_SYMBOL_GPL(driver_add_kobj);
*/
struct device_driver * get_driver(struct device_driver * drv)
{
- return drv ? to_drv(kobject_get(&drv->kobj)) : NULL;
+ if (drv) {
+ struct driver_private *priv;
+ struct kobject *kobj;
+
+ kobj = kobject_get(&drv->p->kobj);
+ priv = to_driver(kobj);
+ return priv->driver;
+ }
+ return NULL;
}

@@ -163,7 +172,7 @@ struct device_driver * get_driver(struct device_driver * drv)
*/
void put_driver(struct device_driver * drv)
{
- kobject_put(&drv->kobj);
+ kobject_put(&drv->p->kobj);
}

static int driver_add_groups(struct device_driver *drv,
@@ -174,10 +183,10 @@ static int driver_add_groups(struct device_driver *drv,

if (groups) {
for (i = 0; groups[i]; i++) {
- error = sysfs_create_group(&drv->kobj, groups[i]);
+ error = sysfs_create_group(&drv->p->kobj, groups[i]);
if (error) {
while (--i >= 0)
- sysfs_remove_group(&drv->kobj,
+ sysfs_remove_group(&drv->p->kobj,
groups[i]);
break;
}
@@ -193,7 +202,7 @@ static void driver_remove_groups(struct device_driver *drv,

if (groups)
for (i = 0; groups[i]; i++)
- sysfs_remove_group(&drv->kobj, groups[i]);
+ sysfs_remove_group(&drv->p->kobj, groups[i]);
}

@@ -214,7 +223,6 @@ int driver_register(struct device_driver * drv)
(drv->bus->shutdown && drv->shutdown)) {
printk(KERN_WARNING "Driver '%s' needs updating - please use bus_type methods\n", drv->name);
}
- klist_init(&drv->klist_devices, NULL, NULL);
ret = bus_add_driver(drv);
if (ret)
return ret;
@@ -250,8 +258,12 @@ void driver_unregister(struct device_driver * drv)
struct device_driver *driver_find(const char *name, struct bus_type *bus)
{
struct kobject *k = kset_find_obj(bus->p->drivers_kset, name);
- if (k)
- return to_drv(k);
+ struct driver_private *priv;
+
+ if (k) {
+ priv = to_driver(k);
+ return priv->driver;
+ }
return NULL;
}

diff --git a/drivers/base/module.c b/drivers/base/module.c
index cad07be..103be9c 100644
--- a/drivers/base/module.c
+++ b/drivers/base/module.c
@@ -50,7 +50,7 @@ void module_add_driver(struct module *mod, struct device_driver *drv)
if (mkobj) {
mk = container_of(mkobj, struct module_kobject, kobj);
/* remember our module structure */
- drv->mkobj = mk;
+ drv->p->mkobj = mk;
/* kset_find_obj took a reference */
kobject_put(mkobj);
}
@@ -60,11 +60,11 @@ void module_add_driver(struct module *mod, struct device_driver *drv)
return;

/* Don't check return codes; these calls are idempotent */
- no_warn = sysfs_create_link(&drv->kobj, &mk->kobj, "module");
+ no_warn = sysfs_create_link(&drv->p->kobj, &mk->kobj, "module");
driver_name = make_driver_name(drv);
if (driver_name) {
module_create_drivers_dir(mk);
- no_warn = sysfs_create_link(mk->drivers_dir, &drv->kobj,
+ no_warn = sysfs_create_link(mk->drivers_dir, &drv->p->kobj,
driver_name);
kfree(driver_name);
}
@@ -78,12 +78,12 @@ void module_remove_driver(struct device_driver *drv)
if (!drv)
return;

- sysfs_remove_link(&drv->kobj, "module");
+ sysfs_remove_link(&drv->p->kobj, "module");

if (drv->owner)
mk = &drv->owner->mkobj;
- else if (drv->mkobj)
- mk = drv->mkobj;
+ else if (drv->p->mkobj)
+ mk = drv->p->mkobj;
if (mk && mk->drivers_dir) {
driver_name = make_driver_name(drv);
if (driver_name) {
diff --git a/drivers/base/platform.c b/drivers/base/platform.c
index d56a05f..bdd59e8 100644
--- a/drivers/base/platform.c
+++ b/drivers/base/platform.c
@@ -499,7 +499,7 @@ int __init_or_module platform_driver_probe(struct platform_driver *drv,
*/
spin_lock(&platform_bus_type.p->klist_drivers.k_lock);
drv->probe = NULL;
- if (code == 0 && list_empty(&drv->driver.klist_devices.k_list))
+ if (code == 0 && list_empty(&drv->driver.p->klist_devices.k_list))
retval = -ENODEV;
drv->driver.probe = platform_drv_probe_fail;
spin_unlock(&platform_bus_type.p->klist_drivers.k_lock);
diff --git a/include/linux/device.h b/include/linux/device.h
index 721ee31..92ba3a8 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -32,6 +32,7 @@

struct device;
struct device_driver;
+struct driver_private;
struct class;
struct class_device;
struct bus_type;
@@ -113,16 +114,11 @@ extern struct kset *bus_get_kset(struct bus_type *bus);
extern struct klist *bus_get_device_klist(struct bus_type *bus);

struct device_driver {
- const char * name;
- struct bus_type * bus;
-
- struct kobject kobj;
- struct klist klist_devices;
- struct klist_node knode_bus;
+ const char *name;
+ struct bus_type *bus;

- struct module * owner;
- const char * mod_name; /* used for built-in modules */
- struct module_kobject * mkobj;
+ struct module *owner;
+ const char *mod_name; /* used for built-in modules */

int (*probe) (struct device * dev);
int (*remove) (struct device * dev);
@@ -130,6 +126,8 @@ struct device_driver {
int (*suspend) (struct device * dev, pm_message_t state);
int (*resume) (struct device * dev);
struct attribute_group **groups;
+
+ struct driver_private *p;
};

--
1.5.3.8