[PATCH] Add a klist to struct device_driver for the devices bound to it.

- Use it in driver_for_each_device() instead of the regular list_head and stop using
  the bus's rwsem for protection.
- Use driver_for_each_device() in driver_detach() so we don't deadlock on the
  bus's rwsem.
- Remove ->devices.
- Move klist access and sysfs link access out from under device's semaphore, since
  they're synchronized through other means.

Signed-off-by: Patrick Mochel <mochel@digitalimplant.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
mochel@digitalimplant.org 2005-03-21 12:25:36 -08:00 committed by Greg Kroah-Hartman
parent 38fdac3cdc
commit 94e7b1c5ff
4 changed files with 37 additions and 29 deletions

View File

@ -209,8 +209,8 @@ void device_initialize(struct device *dev)
kobject_init(&dev->kobj);
INIT_LIST_HEAD(&dev->node);
INIT_LIST_HEAD(&dev->children);
INIT_LIST_HEAD(&dev->driver_list);
INIT_LIST_HEAD(&dev->bus_list);
INIT_LIST_HEAD(&dev->driver_list);
INIT_LIST_HEAD(&dev->dma_pools);
init_MUTEX(&dev->sem);
}

View File

@ -40,7 +40,7 @@ void device_bind_driver(struct device * dev)
{
pr_debug("bound device '%s' to driver '%s'\n",
dev->bus_id, dev->driver->name);
list_add_tail(&dev->driver_list, &dev->driver->devices);
klist_add_tail(&dev->driver->klist_devices, &dev->knode_driver);
sysfs_create_link(&dev->driver->kobj, &dev->kobj,
kobject_name(&dev->kobj));
sysfs_create_link(&dev->kobj, &dev->driver->kobj, "driver");
@ -164,31 +164,35 @@ void driver_attach(struct device_driver * drv)
*/
void device_release_driver(struct device * dev)
{
struct device_driver * drv;
struct device_driver * drv = dev->driver;
if (!drv)
return;
sysfs_remove_link(&drv->kobj, kobject_name(&dev->kobj));
sysfs_remove_link(&dev->kobj, "driver");
klist_remove(&dev->knode_driver);
down(&dev->sem);
drv = dev->driver;
if (drv) {
sysfs_remove_link(&drv->kobj, kobject_name(&dev->kobj));
sysfs_remove_link(&dev->kobj, "driver");
list_del_init(&dev->driver_list);
if (drv->remove)
drv->remove(dev);
dev->driver = NULL;
}
if (drv->remove)
drv->remove(dev);
dev->driver = NULL;
up(&dev->sem);
}
static int __remove_driver(struct device * dev, void * unused)
{
device_release_driver(dev);
return 0;
}
/**
* driver_detach - detach driver from all devices it controls.
* @drv: driver.
*/
void driver_detach(struct device_driver * drv)
{
while (!list_empty(&drv->devices)) {
struct device * dev = container_of(drv->devices.next, struct device, driver_list);
device_release_driver(dev);
}
driver_for_each_device(drv, NULL, NULL, __remove_driver);
}

View File

@ -19,6 +19,12 @@
#define to_drv(obj) container_of(obj, struct device_driver, kobj)
static struct device * next_device(struct klist_iter * i)
{
struct klist_node * n = klist_next(i);
return n ? container_of(n, struct device, knode_driver) : NULL;
}
/**
* driver_for_each_device - Iterator for devices bound to a driver.
* @drv: Driver we're iterating.
@ -32,21 +38,18 @@
int driver_for_each_device(struct device_driver * drv, struct device * start,
void * data, int (*fn)(struct device *, void *))
{
struct list_head * head;
struct klist_iter i;
struct device * dev;
int error = 0;
down_read(&drv->bus->subsys.rwsem);
head = &drv->devices;
dev = list_prepare_entry(start, head, driver_list);
list_for_each_entry_continue(dev, head, driver_list) {
get_device(dev);
if (!drv)
return -EINVAL;
klist_iter_init_node(&drv->klist_devices, &i,
start ? &start->knode_driver : NULL);
while ((dev = next_device(&i)) && !error)
error = fn(dev, data);
put_device(dev);
if (error)
break;
}
up_read(&drv->bus->subsys.rwsem);
klist_iter_exit(&i);
return error;
}
@ -120,7 +123,7 @@ void put_driver(struct device_driver * drv)
*/
int driver_register(struct device_driver * drv)
{
INIT_LIST_HEAD(&drv->devices);
klist_init(&drv->klist_devices);
init_completion(&drv->unloaded);
return bus_add_driver(drv);
}

View File

@ -105,7 +105,7 @@ struct device_driver {
struct completion unloaded;
struct kobject kobj;
struct list_head devices;
struct klist klist_devices;
struct klist_node knode_bus;
struct module * owner;
@ -266,6 +266,7 @@ struct device {
struct list_head bus_list; /* node in bus's list */
struct list_head driver_list;
struct list_head children;
struct klist_node knode_driver;
struct klist_node knode_bus;
struct device * parent;