[PATCH 46/47] Driver core: Remove unneeded routines from driver core

Greg KH
2006-09-26T05:42:49Z

From: Alan Stern <stern@rowland.harvard.edu>

This patch (as783) simplifies the driver core slightly by removing four
unnecessary _get and _put methods.

It is vital that when a driver is removed from its bus's klist of
registered drivers, or when a device is removed from a driver's klist
of bound devices, that the klist updates complete synchronously.
Otherwise the kernel might try binding an unregistered driver to a
newly-registered device, or adding a device to the klist for a new
driver before it has been removed from the old driver's klist.

Since the removals must be synchronous, they don't need to update any
reference counts. Hence the _get and _put methods can be dispensed
with.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---
drivers/base/bus.c | 18 +-----------------
drivers/base/driver.c | 16 +---------------
2 files changed, 2 insertions(+), 32 deletions(-)

diff --git a/drivers/base/bus.c b/drivers/base/bus.c
index 636af53..12173d1 100644
--- a/drivers/base/bus.c
+++ b/drivers/base/bus.c
@@ -696,22 +696,6 @@ static void klist_devices_put(struct kli
put_device(dev);
}

-static void klist_drivers_get(struct klist_node *n)
-{
- struct device_driver *drv = container_of(n, struct device_driver,
- knode_bus);
-
- get_driver(drv);
-}
-
-static void klist_drivers_put(struct klist_node *n)
-{
- struct device_driver *drv = container_of(n, struct device_driver,
- knode_bus);
-
- put_driver(drv);
-}
-
/**
* bus_register - register a bus with the system.
* @bus: bus.
@@ -747,7 +731,7 @@ int bus_register(struct bus_type * bus)
goto bus_drivers_fail;

klist_init(&bus->klist_devices, klist_devices_get, klist_devices_put);
- klist_init(&bus->klist_drivers, klist_drivers_get, klist_drivers_put);
+ klist_init(&bus->klist_drivers, NULL, NULL);
bus_add_attrs(bus);

pr_debug("bus type '%s' registered\n", bus->name);
diff --git a/drivers/base/driver.c b/drivers/base/driver.c
index 562600d..1214cbd 100644
--- a/drivers/base/driver.c
+++ b/drivers/base/driver.c
@@ -142,20 +142,6 @@ void put_driver(struct device_driver * d
kobject_put(&drv->kobj);
}

-static void klist_devices_get(struct klist_node *n)
-{
- struct device *dev = container_of(n, struct device, knode_driver);
-
- get_device(dev);
-}
-
-static void klist_devices_put(struct klist_node *n)
-{
- struct device *dev = container_of(n, struct device, knode_driver);
-
- put_device(dev);
-}
-
/**
* driver_register - register driver with bus
* @drv: driver to register
@@ -175,7 +161,7 @@ int driver_register(struct device_driver
(drv->bus->shutdown && drv->shutdown)) {
printk(KERN_WARNING "Driver '%s' needs updating - please use bus_type methods\n", drv->name);
}
- klist_init(&drv->klist_devices, klist_devices_get, klist_devices_put);
+ klist_init(&drv->klist_devices, NULL, NULL);
init_completion(&drv->unloaded);
return bus_add_driver(drv);
}
--
1.4.2.1