[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>
diff --git a/drivers/base/driver.c b/drivers/base/driver.c
index 484fed1..34bd38a 100644
--- a/drivers/base/driver.c
+++ b/drivers/base/driver.c
@@ -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 @@
*/
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);
}