driver core: bus: bus_add/probe/remove_device() cleanups

Convert the bus_add_device(), bus_probe_device(), and
bus_remove_device() functions to use bus_to_subsys() and not use the
back-pointer to the private structure.

Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Link: https://lore.kernel.org/r/20230208111330.439504-7-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Greg Kroah-Hartman 2023-02-08 12:13:15 +01:00
parent a00fdb988d
commit 5221b82d46

View file

@ -466,32 +466,46 @@ EXPORT_SYMBOL_GPL(bus_for_each_drv);
*/
int bus_add_device(struct device *dev)
{
struct bus_type *bus = bus_get(dev->bus);
int error = 0;
struct subsys_private *sp = bus_to_subsys(dev->bus);
int error;
if (bus) {
pr_debug("bus: '%s': add device %s\n", bus->name, dev_name(dev));
error = device_add_groups(dev, bus->dev_groups);
if (error)
goto out_put;
error = sysfs_create_link(&bus->p->devices_kset->kobj,
&dev->kobj, dev_name(dev));
if (error)
goto out_groups;
error = sysfs_create_link(&dev->kobj,
&dev->bus->p->subsys.kobj, "subsystem");
if (error)
goto out_subsys;
klist_add_tail(&dev->p->knode_bus, &bus->p->klist_devices);
if (!sp) {
/*
* This is a normal operation for many devices that do not
* have a bus assigned to them, just say that all went
* well.
*/
return 0;
}
/*
* Reference in sp is now incremented and will be dropped when
* the device is removed from the bus
*/
pr_debug("bus: '%s': add device %s\n", sp->bus->name, dev_name(dev));
error = device_add_groups(dev, sp->bus->dev_groups);
if (error)
goto out_put;
error = sysfs_create_link(&sp->devices_kset->kobj, &dev->kobj, dev_name(dev));
if (error)
goto out_groups;
error = sysfs_create_link(&dev->kobj, &sp->subsys.kobj, "subsystem");
if (error)
goto out_subsys;
klist_add_tail(&dev->p->knode_bus, &sp->klist_devices);
return 0;
out_subsys:
sysfs_remove_link(&bus->p->devices_kset->kobj, dev_name(dev));
sysfs_remove_link(&sp->devices_kset->kobj, dev_name(dev));
out_groups:
device_remove_groups(dev, bus->dev_groups);
device_remove_groups(dev, sp->bus->dev_groups);
out_put:
bus_put(dev->bus);
subsys_put(sp);
return error;
}
@ -503,20 +517,21 @@ int bus_add_device(struct device *dev)
*/
void bus_probe_device(struct device *dev)
{
struct bus_type *bus = dev->bus;
struct subsys_private *sp = bus_to_subsys(dev->bus);
struct subsys_interface *sif;
if (!bus)
if (!sp)
return;
if (bus->p->drivers_autoprobe)
if (sp->drivers_autoprobe)
device_initial_probe(dev);
mutex_lock(&bus->p->mutex);
list_for_each_entry(sif, &bus->p->interfaces, node)
mutex_lock(&sp->mutex);
list_for_each_entry(sif, &sp->interfaces, node)
if (sif->add_dev)
sif->add_dev(dev, sif);
mutex_unlock(&bus->p->mutex);
mutex_unlock(&sp->mutex);
subsys_put(sp);
}
/**
@ -531,21 +546,20 @@ void bus_probe_device(struct device *dev)
*/
void bus_remove_device(struct device *dev)
{
struct bus_type *bus = dev->bus;
struct subsys_private *sp = bus_to_subsys(dev->bus);
struct subsys_interface *sif;
if (!bus)
if (!sp)
return;
mutex_lock(&bus->p->mutex);
list_for_each_entry(sif, &bus->p->interfaces, node)
mutex_lock(&sp->mutex);
list_for_each_entry(sif, &sp->interfaces, node)
if (sif->remove_dev)
sif->remove_dev(dev, sif);
mutex_unlock(&bus->p->mutex);
mutex_unlock(&sp->mutex);
sysfs_remove_link(&dev->kobj, "subsystem");
sysfs_remove_link(&dev->bus->p->devices_kset->kobj,
dev_name(dev));
sysfs_remove_link(&sp->devices_kset->kobj, dev_name(dev));
device_remove_groups(dev, dev->bus->dev_groups);
if (klist_node_attached(&dev->p->knode_bus))
klist_del(&dev->p->knode_bus);
@ -553,7 +567,14 @@ void bus_remove_device(struct device *dev)
pr_debug("bus: '%s': remove device %s\n",
dev->bus->name, dev_name(dev));
device_release_driver(dev);
bus_put(dev->bus);
/*
* Decrement the reference count twice, once for the bus_to_subsys()
* call in the start of this function, and the second one from the
* reference increment in bus_add_device()
*/
subsys_put(sp);
subsys_put(sp);
}
static int __must_check add_bind_files(struct device_driver *drv)