Commit c6f7e72a authored by Greg Kroah-Hartman's avatar Greg Kroah-Hartman
Browse files

driver core: remove fields from struct bus_type 



struct bus_type is static everywhere in the kernel.  This moves the
kobject in the structure out of it, and a bunch of other private only to
the driver core fields are now moved to a private structure.  This lets
us dynamically create the backing kobject properly and gives us the
chance to be able to document to users exactly how to use the struct
bus_type as there are no fields they can improperly access.

Thanks to Kay for the build fixes on this patch.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent b249072e

drivers/base/base.h

+29 −1
Original line number Diff line number Diff line 


/* initialisation functions */

/**

 * struct bus_type_private - structure to hold the private to the driver core portions of the bus_type structure.

 *

 * @subsys - the struct kset that defines this bus.  This is the main kobject

 * @drivers_kset - the list of drivers associated with this bus

 * @devices_kset - the list of devices associated with this bus

 * @klist_devices - the klist to iterate over the @devices_kset

 * @klist_drivers - the klist to iterate over the @drivers_kset

 * @bus_notifier - the bus notifier list for anything that cares about things

 * on this bus.

 * @bus - pointer back to the struct bus_type that this structure is associated

 * with.

 *

 * This structure is the one that is the actual kobject allowing struct

 * bus_type to be statically allocated safely.  Nothing outside of the driver

 * core should ever touch these fields.

 */

struct bus_type_private {

	struct kset subsys;

	struct kset *drivers_kset;

	struct kset *devices_kset;

	struct klist klist_devices;

	struct klist klist_drivers;

	struct blocking_notifier_head bus_notifier;

	unsigned int drivers_autoprobe:1;

	struct bus_type *bus;

};





/* initialisation functions */

extern int devices_init(void);

extern int buses_init(void);

extern int classes_init(void);

drivers/base/bus.c

+65 −51
Original line number Diff line number Diff line
@@ -17,7 +17,7 @@ 
#include "power/power.h"



#define to_bus_attr(_attr) container_of(_attr, struct bus_attribute, attr)

#define to_bus(obj) container_of(obj, struct bus_type, subsys.kobj)

#define to_bus(obj) container_of(obj, struct bus_type_private, subsys.kobj)



/*

 * sysfs bindings for drivers
@@ -32,13 +32,17 @@ static int __must_check bus_rescan_devices_helper(struct device *dev, 


static struct bus_type *bus_get(struct bus_type *bus)

{

	return bus ? container_of(kset_get(&bus->subsys),

				struct bus_type, subsys) : NULL;

	if (bus) {

		kset_get(&bus->p->subsys);

		return bus;

	}

	return NULL;

}



static void bus_put(struct bus_type *bus)

{

	kset_put(&bus->subsys);

	if (bus)

		kset_put(&bus->p->subsys);

}



static ssize_t
@@ -104,11 +108,11 @@ static ssize_t 
bus_attr_show(struct kobject * kobj, struct attribute * attr, char * buf)

{

	struct bus_attribute * bus_attr = to_bus_attr(attr);

	struct bus_type * bus = to_bus(kobj);

	struct bus_type_private *bus_priv = to_bus(kobj);

	ssize_t ret = 0;



	if (bus_attr->show)

		ret = bus_attr->show(bus, buf);

		ret = bus_attr->show(bus_priv->bus, buf);

	return ret;

}
@@ -117,11 +121,11 @@ bus_attr_store(struct kobject * kobj, struct attribute * attr, 
	       const char * buf, size_t count)

{

	struct bus_attribute * bus_attr = to_bus_attr(attr);

	struct bus_type * bus = to_bus(kobj);

	struct bus_type_private *bus_priv = to_bus(kobj);

	ssize_t ret = 0;



	if (bus_attr->store)

		ret = bus_attr->store(bus, buf, count);

		ret = bus_attr->store(bus_priv->bus, buf, count);

	return ret;

}
@@ -134,7 +138,7 @@ int bus_create_file(struct bus_type * bus, struct bus_attribute * attr) 
{

	int error;

	if (bus_get(bus)) {

		error = sysfs_create_file(&bus->subsys.kobj, &attr->attr);

		error = sysfs_create_file(&bus->p->subsys.kobj, &attr->attr);

		bus_put(bus);

	} else

		error = -EINVAL;
@@ -144,7 +148,7 @@ int bus_create_file(struct bus_type * bus, struct bus_attribute * attr) 
void bus_remove_file(struct bus_type * bus, struct bus_attribute * attr)

{

	if (bus_get(bus)) {

		sysfs_remove_file(&bus->subsys.kobj, &attr->attr);

		sysfs_remove_file(&bus->p->subsys.kobj, &attr->attr);

		bus_put(bus);

	}

}
@@ -237,16 +241,16 @@ static DRIVER_ATTR(bind, S_IWUSR, NULL, driver_bind); 


static ssize_t show_drivers_autoprobe(struct bus_type *bus, char *buf)

{

	return sprintf(buf, "%d\n", bus->drivers_autoprobe);

	return sprintf(buf, "%d\n", bus->p->drivers_autoprobe);

}



static ssize_t store_drivers_autoprobe(struct bus_type *bus,

				       const char *buf, size_t count)

{

	if (buf[0] == '0')

		bus->drivers_autoprobe = 0;

		bus->p->drivers_autoprobe = 0;

	else

		bus->drivers_autoprobe = 1;

		bus->p->drivers_autoprobe = 1;

	return count;

}
@@ -300,7 +304,7 @@ int bus_for_each_dev(struct bus_type * bus, struct device * start, 
	if (!bus)

		return -EINVAL;



	klist_iter_init_node(&bus->klist_devices, &i,

	klist_iter_init_node(&bus->p->klist_devices, &i,

			     (start ? &start->knode_bus : NULL));

	while ((dev = next_device(&i)) && !error)

		error = fn(dev, data);
@@ -333,7 +337,7 @@ struct device * bus_find_device(struct bus_type *bus, 
	if (!bus)

		return NULL;



	klist_iter_init_node(&bus->klist_devices, &i,

	klist_iter_init_node(&bus->p->klist_devices, &i,

			     (start ? &start->knode_bus : NULL));

	while ((dev = next_device(&i)))

		if (match(dev, data) && get_device(dev))
@@ -379,7 +383,7 @@ int bus_for_each_drv(struct bus_type * bus, struct device_driver * start, 
	if (!bus)

		return -EINVAL;



	klist_iter_init_node(&bus->klist_drivers, &i,

	klist_iter_init_node(&bus->p->klist_drivers, &i,

			     start ? &start->knode_bus : NULL);

	while ((drv = next_driver(&i)) && !error)

		error = fn(drv, data);
@@ -420,7 +424,7 @@ static void device_remove_attrs(struct bus_type * bus, struct device * dev) 
static int make_deprecated_bus_links(struct device *dev)

{

	return sysfs_create_link(&dev->kobj,

				 &dev->bus->subsys.kobj, "bus");

				 &dev->bus->p->subsys.kobj, "bus");

}



static void remove_deprecated_bus_links(struct device *dev)
@@ -449,12 +453,12 @@ int bus_add_device(struct device * dev) 
		error = device_add_attrs(bus, dev);

		if (error)

			goto out_put;

		error = sysfs_create_link(&bus->devices_kset->kobj,

		error = sysfs_create_link(&bus->p->devices_kset->kobj,

						&dev->kobj, dev->bus_id);

		if (error)

			goto out_id;

		error = sysfs_create_link(&dev->kobj,

				&dev->bus->subsys.kobj, "subsystem");

				&dev->bus->p->subsys.kobj, "subsystem");

		if (error)

			goto out_subsys;

		error = make_deprecated_bus_links(dev);
@@ -466,7 +470,7 @@ int bus_add_device(struct device * dev) 
out_deprecated:

	sysfs_remove_link(&dev->kobj, "subsystem");

out_subsys:

	sysfs_remove_link(&bus->devices_kset->kobj, dev->bus_id);

	sysfs_remove_link(&bus->p->devices_kset->kobj, dev->bus_id);

out_id:

	device_remove_attrs(bus, dev);

out_put:
@@ -488,11 +492,11 @@ void bus_attach_device(struct device * dev) 


	if (bus) {

		dev->is_registered = 1;

		if (bus->drivers_autoprobe)

		if (bus->p->drivers_autoprobe)

			ret = device_attach(dev);

		WARN_ON(ret < 0);

		if (ret >= 0)

			klist_add_tail(&dev->knode_bus, &bus->klist_devices);

			klist_add_tail(&dev->knode_bus, &bus->p->klist_devices);

		else

			dev->is_registered = 0;

	}
@@ -512,7 +516,7 @@ void bus_remove_device(struct device * dev) 
	if (dev->bus) {

		sysfs_remove_link(&dev->kobj, "subsystem");

		remove_deprecated_bus_links(dev);

		sysfs_remove_link(&dev->bus->devices_kset->kobj, dev->bus_id);

		sysfs_remove_link(&dev->bus->p->devices_kset->kobj, dev->bus_id);

		device_remove_attrs(dev->bus, dev);

		if (dev->is_registered) {

			dev->is_registered = 0;
@@ -638,18 +642,18 @@ int bus_add_driver(struct device_driver *drv) 
	error = kobject_set_name(&drv->kobj, "%s", drv->name);

	if (error)

		goto out_put_bus;

	drv->kobj.kset = bus->drivers_kset;

	drv->kobj.kset = bus->p->drivers_kset;

	drv->kobj.ktype = &driver_ktype;

	error = kobject_register(&drv->kobj);

	if (error)

		goto out_put_bus;



	if (drv->bus->drivers_autoprobe) {

	if (drv->bus->p->drivers_autoprobe) {

		error = driver_attach(drv);

		if (error)

			goto out_unregister;

	}

	klist_add_tail(&drv->knode_bus, &bus->klist_drivers);

	klist_add_tail(&drv->knode_bus, &bus->p->klist_drivers);

	module_add_driver(drv->owner, drv);



	error = driver_create_file(drv, &driver_attr_uevent);
@@ -828,7 +832,7 @@ static ssize_t bus_uevent_store(struct bus_type *bus, 
	enum kobject_action action;



	if (kobject_action_type(buf, count, &action) == 0)

		kobject_uevent(&bus->subsys.kobj, action);

		kobject_uevent(&bus->p->subsys.kobj, action);

	return count;

}

static BUS_ATTR(uevent, S_IWUSR, NULL, bus_uevent_store);
@@ -844,17 +848,26 @@ static BUS_ATTR(uevent, S_IWUSR, NULL, bus_uevent_store); 
int bus_register(struct bus_type * bus)

{

	int retval;

	struct bus_type_private *priv;



	priv = kzalloc(sizeof(struct bus_type_private), GFP_KERNEL);

	if (!priv)

		return -ENOMEM;



	priv->bus = bus;

	bus->p = priv;



	BLOCKING_INIT_NOTIFIER_HEAD(&bus->bus_notifier);

	BLOCKING_INIT_NOTIFIER_HEAD(&priv->bus_notifier);



	retval = kobject_set_name(&bus->subsys.kobj, "%s", bus->name);

	retval = kobject_set_name(&priv->subsys.kobj, "%s", bus->name);

	if (retval)

		goto out;



	bus->subsys.kobj.kset = bus_kset;

	bus->subsys.kobj.ktype = &bus_ktype;

	priv->subsys.kobj.kset = bus_kset;

	priv->subsys.kobj.ktype = &bus_ktype;

	priv->drivers_autoprobe = 1;



	retval = kset_register(&bus->subsys);

	retval = kset_register(&priv->subsys);

	if (retval)

		goto out;
@@ -862,24 +875,23 @@ int bus_register(struct bus_type * bus) 
	if (retval)

		goto bus_uevent_fail;



	bus->devices_kset = kset_create_and_add("devices", NULL,

						&bus->subsys.kobj);

	if (!bus->devices_kset) {

	priv->devices_kset = kset_create_and_add("devices", NULL,

						 &priv->subsys.kobj);

	if (!priv->devices_kset) {

		retval = -ENOMEM;

		goto bus_devices_fail;

	}



	bus->drivers_kset = kset_create_and_add("drivers", NULL,

						&bus->subsys.kobj);

	if (!bus->drivers_kset) {

	priv->drivers_kset = kset_create_and_add("drivers", NULL,

						 &priv->subsys.kobj);

	if (!priv->drivers_kset) {

		retval = -ENOMEM;

		goto bus_drivers_fail;

	}



	klist_init(&bus->klist_devices, klist_devices_get, klist_devices_put);

	klist_init(&bus->klist_drivers, NULL, NULL);

	klist_init(&priv->klist_devices, klist_devices_get, klist_devices_put);

	klist_init(&priv->klist_drivers, NULL, NULL);



	bus->drivers_autoprobe = 1;

	retval = add_probe_files(bus);

	if (retval)

		goto bus_probe_files_fail;
@@ -894,13 +906,14 @@ int bus_register(struct bus_type * bus) 
bus_attrs_fail:

	remove_probe_files(bus);

bus_probe_files_fail:

	kset_unregister(bus->drivers_kset);

	kset_unregister(bus->p->drivers_kset);

bus_drivers_fail:

	kset_unregister(bus->devices_kset);

	kset_unregister(bus->p->devices_kset);

bus_devices_fail:

	bus_remove_file(bus, &bus_attr_uevent);

bus_uevent_fail:

	kset_unregister(&bus->subsys);

	kset_unregister(&bus->p->subsys);

	kfree(bus->p);

out:

	return retval;

}
@@ -917,33 +930,34 @@ void bus_unregister(struct bus_type * bus) 
	pr_debug("bus %s: unregistering\n", bus->name);

	bus_remove_attrs(bus);

	remove_probe_files(bus);

	kset_unregister(bus->drivers_kset);

	kset_unregister(bus->devices_kset);

	kset_unregister(bus->p->drivers_kset);

	kset_unregister(bus->p->devices_kset);

	bus_remove_file(bus, &bus_attr_uevent);

	kset_unregister(&bus->subsys);

	kset_unregister(&bus->p->subsys);

	kfree(bus->p);

}



int bus_register_notifier(struct bus_type *bus, struct notifier_block *nb)

{

	return blocking_notifier_chain_register(&bus->bus_notifier, nb);

	return blocking_notifier_chain_register(&bus->p->bus_notifier, nb);

}

EXPORT_SYMBOL_GPL(bus_register_notifier);



int bus_unregister_notifier(struct bus_type *bus, struct notifier_block *nb)

{

	return blocking_notifier_chain_unregister(&bus->bus_notifier, nb);

	return blocking_notifier_chain_unregister(&bus->p->bus_notifier, nb);

}

EXPORT_SYMBOL_GPL(bus_unregister_notifier);



struct kset *bus_get_kset(struct bus_type *bus)

{

	return &bus->subsys;

	return &bus->p->subsys;

}

EXPORT_SYMBOL_GPL(bus_get_kset);



struct klist *bus_get_device_klist(struct bus_type *bus)

{

	return &bus->klist_devices;

	return &bus->p->klist_devices;

}

EXPORT_SYMBOL_GPL(bus_get_device_klist);

drivers/base/core.c

+3 −3
Original line number Diff line number Diff line
@@ -769,7 +769,7 @@ int device_add(struct device *dev) 


	/* notify clients of device entry (new way) */

	if (dev->bus)

		blocking_notifier_call_chain(&dev->bus->bus_notifier,

		blocking_notifier_call_chain(&dev->bus->p->bus_notifier,

					     BUS_NOTIFY_ADD_DEVICE, dev);



	error = device_create_file(dev, &uevent_attr);
@@ -820,7 +820,7 @@ int device_add(struct device *dev) 
	dpm_sysfs_remove(dev);

 PMError:

	if (dev->bus)

		blocking_notifier_call_chain(&dev->bus->bus_notifier,

		blocking_notifier_call_chain(&dev->bus->p->bus_notifier,

					     BUS_NOTIFY_DEL_DEVICE, dev);

	device_remove_attrs(dev);

 AttrsError:
@@ -999,7 +999,7 @@ void device_del(struct device * dev) 
	if (platform_notify_remove)

		platform_notify_remove(dev);

	if (dev->bus)

		blocking_notifier_call_chain(&dev->bus->bus_notifier,

		blocking_notifier_call_chain(&dev->bus->p->bus_notifier,

					     BUS_NOTIFY_DEL_DEVICE, dev);

	kobject_uevent(&dev->kobj, KOBJ_REMOVE);

	kobject_del(&dev->kobj);

drivers/base/dd.c

+2 −2
Original line number Diff line number Diff line
@@ -38,7 +38,7 @@ static void driver_bound(struct device *dev) 
		 dev->bus_id, dev->driver->name);



	if (dev->bus)

		blocking_notifier_call_chain(&dev->bus->bus_notifier,

		blocking_notifier_call_chain(&dev->bus->p->bus_notifier,

					     BUS_NOTIFY_BOUND_DRIVER, dev);



	klist_add_tail(&dev->knode_driver, &dev->driver->klist_devices);
@@ -296,7 +296,7 @@ static void __device_release_driver(struct device * dev) 
		klist_remove(&dev->knode_driver);



		if (dev->bus)

			blocking_notifier_call_chain(&dev->bus->bus_notifier,

			blocking_notifier_call_chain(&dev->bus->p->bus_notifier,

						     BUS_NOTIFY_UNBIND_DRIVER,

						     dev);

drivers/base/driver.c

+1 −1
Original line number Diff line number Diff line
@@ -185,7 +185,7 @@ 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->drivers_kset, name);

	struct kobject *k = kset_find_obj(bus->p->drivers_kset, name);

	if (k)

		return to_drv(k);

	return NULL;

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