[PATCH 07/21] driver core: bus: bus_register/unregister() cleanups

Greg Kroah-Hartman
2023-02-08T11:15:38Z

Convert the bus_register() and bus_unregister() functions to use
bus_to_subsys() and not use the back-pointer to the private structure.

Because bus_add_groups() and bus_remove_groups() were only called in one
place, remove those one-line-wrapper functions and call the real sysfs
group function where it is needed instead, saving another layer of
indirection.

Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/base/bus.c | 54 ++++++++++++++++++++++------------------------
1 file changed, 26 insertions(+), 28 deletions(-)

diff --git a/drivers/base/bus.c b/drivers/base/bus.c
index f4e4efd81b29..549e55dfbfda 100644
--- a/drivers/base/bus.c
+++ b/drivers/base/bus.c
@@ -774,18 +774,6 @@ int device_reprobe(struct device *dev)
}
EXPORT_SYMBOL_GPL(device_reprobe);

-static int bus_add_groups(struct bus_type *bus,
- const struct attribute_group **groups)
-{
- return sysfs_create_groups(&bus->p->subsys.kobj, groups);
-}
-
-static void bus_remove_groups(struct bus_type *bus,
- const struct attribute_group **groups)
-{
- sysfs_remove_groups(&bus->p->subsys.kobj, groups);
-}
-
static void klist_devices_get(struct klist_node *n)
{
struct device_private *dev_prv = to_device_private_bus(n);
@@ -839,6 +827,7 @@ int bus_register(struct bus_type *bus)
{
int retval;
struct subsys_private *priv;
+ struct kobject *bus_kobj;
struct lock_class_key *key;

priv = kzalloc(sizeof(struct subsys_private), GFP_KERNEL);
@@ -850,12 +839,13 @@ int bus_register(struct bus_type *bus)

BLOCKING_INIT_NOTIFIER_HEAD(&priv->bus_notifier);

- retval = kobject_set_name(&priv->subsys.kobj, "%s", bus->name);
+ bus_kobj = &priv->subsys.kobj;
+ retval = kobject_set_name(bus_kobj, "%s", bus->name);
if (retval)
goto out;

- priv->subsys.kobj.kset = bus_kset;
- priv->subsys.kobj.ktype = &bus_ktype;
+ bus_kobj->kset = bus_kset;
+ bus_kobj->ktype = &bus_ktype;
priv->drivers_autoprobe = 1;

retval = kset_register(&priv->subsys);
@@ -866,15 +856,13 @@ int bus_register(struct bus_type *bus)
if (retval)
goto bus_uevent_fail;

- priv->devices_kset = kset_create_and_add("devices", NULL,
- &priv->subsys.kobj);
+ priv->devices_kset = kset_create_and_add("devices", NULL, bus_kobj);
if (!priv->devices_kset) {
retval = -ENOMEM;
goto bus_devices_fail;
}

- priv->drivers_kset = kset_create_and_add("drivers", NULL,
- &priv->subsys.kobj);
+ priv->drivers_kset = kset_create_and_add("drivers", NULL, bus_kobj);
if (!priv->drivers_kset) {
retval = -ENOMEM;
goto bus_drivers_fail;
@@ -891,7 +879,7 @@ int bus_register(struct bus_type *bus)
if (retval)
goto bus_probe_files_fail;

- retval = bus_add_groups(bus, bus->bus_groups);
+ retval = sysfs_create_groups(bus_kobj, bus->bus_groups);
if (retval)
goto bus_groups_fail;

@@ -901,15 +889,15 @@ int bus_register(struct bus_type *bus)
bus_groups_fail:
remove_probe_files(bus);
bus_probe_files_fail:
- kset_unregister(bus->p->drivers_kset);
+ kset_unregister(priv->drivers_kset);
bus_drivers_fail:
- kset_unregister(bus->p->devices_kset);
+ kset_unregister(priv->devices_kset);
bus_devices_fail:
bus_remove_file(bus, &bus_attr_uevent);
bus_uevent_fail:
- kset_unregister(&bus->p->subsys);
+ kset_unregister(&priv->subsys);
out:
- kfree(bus->p);
+ kfree(priv);
bus->p = NULL;
return retval;
}
@@ -924,15 +912,25 @@ EXPORT_SYMBOL_GPL(bus_register);
*/
void bus_unregister(struct bus_type *bus)
{
+ struct subsys_private *sp = bus_to_subsys(bus);
+ struct kobject *bus_kobj;
+
+ if (!sp)
+ return;
+
pr_debug("bus: '%s': unregistering\n", bus->name);
if (bus->dev_root)
device_unregister(bus->dev_root);
- bus_remove_groups(bus, bus->bus_groups);
+
+ bus_kobj = &sp->subsys.kobj;
+ sysfs_remove_groups(bus_kobj, bus->bus_groups);
remove_probe_files(bus);
- kset_unregister(bus->p->drivers_kset);
- kset_unregister(bus->p->devices_kset);
bus_remove_file(bus, &bus_attr_uevent);
- kset_unregister(&bus->p->subsys);
+
+ kset_unregister(sp->drivers_kset);
+ kset_unregister(sp->devices_kset);
+ kset_unregister(&sp->subsys);
+ subsys_put(sp);
}
EXPORT_SYMBOL_GPL(bus_unregister);

--
2.39.1