2005-03-21 21:01:32

by Patrick Mochel

[permalink] [raw]
Subject: [3/9] [RFC] Steps to fixing the driver model locking


[email protected], 2005-03-21 10:59:56-08:00, [email protected]
[driver core] Add driver_for_each_device().

Now there's an iterator for accessing each device bound to a driver.


Signed-off-by: Patrick Mochel <[email protected]>

diff -Nru a/drivers/base/driver.c b/drivers/base/driver.c
--- a/drivers/base/driver.c 2005-03-21 12:30:44 -08:00
+++ b/drivers/base/driver.c 2005-03-21 12:30:44 -08:00
@@ -18,6 +18,41 @@
#define to_dev(node) container_of(node, struct device, driver_list)
#define to_drv(obj) container_of(obj, struct device_driver, kobj)

+
+/**
+ * driver_for_each_device - Iterator for devices bound to a driver.
+ * @drv: Driver we're iterating.
+ * @data: Data to pass to the callback.
+ * @fn: Function to call for each device.
+ *
+ * Take the bus's rwsem and iterate over the @drv's list of devices,
+ * calling @fn for each one.
+ */
+
+int driver_for_each_device(struct device_driver * drv, struct device * start,
+ void * data, int (*fn)(struct device *, void *))
+{
+ struct list_head * head;
+ 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);
+ error = fn(dev, data);
+ put_device(dev);
+ if (error)
+ break;
+ }
+ up_read(&drv->bus->subsys.rwsem);
+ return error;
+}
+
+EXPORT_SYMBOL(driver_for_each_device);
+
+
/**
* driver_create_file - create sysfs file for driver.
* @drv: driver.
diff -Nru a/include/linux/device.h b/include/linux/device.h
--- a/include/linux/device.h 2005-03-21 12:30:44 -08:00
+++ b/include/linux/device.h 2005-03-21 12:30:44 -08:00
@@ -137,6 +137,9 @@
extern int driver_create_file(struct device_driver *, struct driver_attribute *);
extern void driver_remove_file(struct device_driver *, struct driver_attribute *);

+extern int driver_for_each_device(struct device_driver * drv, struct device * start,
+ void * data, int (*fn)(struct device *, void *));
+

/*
* device classes