From foo@baz Tue Apr 9 12:12:43 2002 To: Greg KH Date: 21 Mar 2005 12:00:18 -08:00 From: mochel@digitalimplant.org Subject: [driver core] Add a klist to struct bus_type for its drivers. - Use it in bus_for_each_drv(). - Use the klist spinlock instead of the bus rwsem. Signed-off-by: Patrick Mochel Signed-off-by: Greg Kroah-Hartman --- drivers/base/bus.c | 52 +++++++++++++++++++++---------------------------- include/linux/device.h | 2 + 2 files changed, 25 insertions(+), 29 deletions(-) --- gregkh-2.6.orig/drivers/base/bus.c 2005-05-05 11:08:04.000000000 -0700 +++ gregkh-2.6/drivers/base/bus.c 2005-05-05 11:08:05.000000000 -0700 @@ -135,30 +135,6 @@ decl_subsys(bus, &ktype_bus, NULL); -static int __bus_for_each_drv(struct bus_type *bus, struct device_driver *start, - void * data, int (*fn)(struct device_driver *, void *)) -{ - struct list_head *head; - struct device_driver *drv; - int error = 0; - - if (!(bus = get_bus(bus))) - return -EINVAL; - - head = &bus->drivers.list; - drv = list_prepare_entry(start, head, kobj.entry); - list_for_each_entry_continue(drv, head, kobj.entry) { - get_driver(drv); - error = fn(drv, data); - put_driver(drv); - if (error) - break; - } - put_bus(bus); - return error; -} - - static struct device * next_device(struct klist_iter * i) { struct klist_node * n = klist_next(i); @@ -203,6 +179,14 @@ return error; } + + +static struct device_driver * next_driver(struct klist_iter * i) +{ + struct klist_node * n = klist_next(i); + return n ? container_of(n, struct device_driver, knode_bus) : NULL; +} + /** * bus_for_each_drv - driver iterator * @bus: bus we're dealing with. @@ -226,12 +210,19 @@ int bus_for_each_drv(struct bus_type * bus, struct device_driver * start, void * data, int (*fn)(struct device_driver *, void *)) { - int ret; + struct klist_iter i; + struct device_driver * drv; + int error = 0; - down_read(&bus->subsys.rwsem); - ret = __bus_for_each_drv(bus, start, data, fn); - up_read(&bus->subsys.rwsem); - return ret; + if (!bus) + return -EINVAL; + + klist_iter_init_node(&bus->klist_drivers, &i, + start ? &start->knode_bus : NULL); + while ((drv = next_driver(&i)) && !error) + error = fn(drv, data); + klist_iter_exit(&i); + return error; } static int device_add_attrs(struct bus_type * bus, struct device * dev) @@ -376,6 +367,7 @@ down_write(&bus->subsys.rwsem); driver_attach(drv); up_write(&bus->subsys.rwsem); + klist_add_tail(&bus->klist_drivers, &drv->knode_bus); module_add_driver(drv->owner, drv); driver_add_attrs(bus, drv); @@ -397,6 +389,7 @@ { if (drv->bus) { driver_remove_attrs(drv->bus, drv); + klist_remove(&drv->knode_bus); down_write(&drv->bus->subsys.rwsem); pr_debug("bus %s: remove driver %s\n", drv->bus->name, drv->name); driver_detach(drv); @@ -536,6 +529,7 @@ goto bus_drivers_fail; klist_init(&bus->klist_devices); + klist_init(&bus->klist_drivers); bus_add_attrs(bus); pr_debug("bus type '%s' registered\n", bus->name); --- gregkh-2.6.orig/include/linux/device.h 2005-05-05 11:08:04.000000000 -0700 +++ gregkh-2.6/include/linux/device.h 2005-05-05 11:08:05.000000000 -0700 @@ -53,6 +53,7 @@ struct kset drivers; struct kset devices; struct klist klist_devices; + struct klist klist_drivers; struct bus_attribute * bus_attrs; struct device_attribute * dev_attrs; @@ -105,6 +106,7 @@ struct completion unloaded; struct kobject kobj; struct list_head devices; + struct klist_node knode_bus; struct module * owner;