Commit e4f05682 authored by Greg Kroah-Hartman's avatar Greg Kroah-Hartman
Browse files

driver core: bus: bus_add/remove_driver() cleanups 

Convert the bus_add_driver() and bus_remove_driver() functions to use
bus_to_subsys() and not use the back-pointer to the private structure.

Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Link: https://lore.kernel.org/r/20230208111330.439504-12-gregkh@linuxfoundation.org


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 32a8121a

drivers/base/bus.c

+26 −13
Original line number Diff line number Diff line
@@ -636,15 +636,18 @@ static DRIVER_ATTR_WO(uevent); 
 */

int bus_add_driver(struct device_driver *drv)

{

	struct bus_type *bus;

	struct subsys_private *sp = bus_to_subsys(drv->bus);

	struct driver_private *priv;

	int error = 0;



	bus = bus_get(drv->bus);

	if (!bus)

	if (!sp)

		return -EINVAL;



	pr_debug("bus: '%s': add driver %s\n", bus->name, drv->name);

	/*

	 * Reference in sp is now incremented and will be dropped when

	 * the driver is removed from the bus

	 */

	pr_debug("bus: '%s': add driver %s\n", sp->bus->name, drv->name);



	priv = kzalloc(sizeof(*priv), GFP_KERNEL);

	if (!priv) {
@@ -654,14 +657,14 @@ int bus_add_driver(struct device_driver *drv) 
	klist_init(&priv->klist_devices, NULL, NULL);

	priv->driver = drv;

	drv->p = priv;

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

	priv->kobj.kset = sp->drivers_kset;

	error = kobject_init_and_add(&priv->kobj, &driver_ktype, NULL,

				     "%s", drv->name);

	if (error)

		goto out_unregister;



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

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

	klist_add_tail(&priv->knode_bus, &sp->klist_drivers);

	if (sp->drivers_autoprobe) {

		error = driver_attach(drv);

		if (error)

			goto out_del_list;
@@ -673,7 +676,7 @@ int bus_add_driver(struct device_driver *drv) 
		printk(KERN_ERR "%s: uevent attr (%s) failed\n",

			__func__, drv->name);

	}

	error = driver_add_groups(drv, bus->drv_groups);

	error = driver_add_groups(drv, sp->bus->drv_groups);

	if (error) {

		/* How the hell do we get out of this pickle? Give up */

		printk(KERN_ERR "%s: driver_add_groups(%s) failed\n",
@@ -698,7 +701,7 @@ int bus_add_driver(struct device_driver *drv) 
	/* drv->p is freed in driver_release()  */

	drv->p = NULL;

out_put_bus:

	bus_put(bus);

	subsys_put(sp);

	return error;

}
@@ -712,19 +715,29 @@ int bus_add_driver(struct device_driver *drv) 
 */

void bus_remove_driver(struct device_driver *drv)

{

	if (!drv->bus)

	struct subsys_private *sp = bus_to_subsys(drv->bus);



	if (!sp)

		return;



	pr_debug("bus: '%s': remove driver %s\n", sp->bus->name, drv->name);



	if (!drv->suppress_bind_attrs)

		remove_bind_files(drv);

	driver_remove_groups(drv, drv->bus->drv_groups);

	driver_remove_groups(drv, sp->bus->drv_groups);

	driver_remove_file(drv, &driver_attr_uevent);

	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_put(&drv->p->kobj);

	bus_put(drv->bus);



	/*

	 * Decrement the reference count twice, once for the bus_to_subsys()

	 * call in the start of this function, and the second one from the

	 * reference increment in bus_add_driver()

	 */

	subsys_put(sp);

	subsys_put(sp);

}



/* Helper for bus_rescan_devices's iter */