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Diffstat (limited to 'drivers')
-rw-r--r--drivers/base/class.c113
1 files changed, 61 insertions, 52 deletions
diff --git a/drivers/base/class.c b/drivers/base/class.c
index c53d6f98cfc6..1f12bd5d56d9 100644
--- a/drivers/base/class.c
+++ b/drivers/base/class.c
@@ -66,24 +66,6 @@ done:
return sp;
}
-static const struct class *class_get(const struct class *class)
-{
- struct subsys_private *sp = class_to_subsys(class);
-
- if (sp)
- return class;
- return NULL;
-}
-
-static void class_put(const struct class *class)
-{
- struct subsys_private *sp = class_to_subsys(class);
-
- /* two puts are required as the call to bus_to_subsys incremented it again */
- subsys_put(sp);
- subsys_put(sp);
-}
-
static ssize_t class_attr_show(struct kobject *kobj, struct attribute *attr,
char *buf)
{
@@ -148,13 +130,15 @@ static const struct kobj_type class_ktype = {
int class_create_file_ns(const struct class *cls, const struct class_attribute *attr,
const void *ns)
{
+ struct subsys_private *sp = class_to_subsys(cls);
int error;
- if (cls)
- error = sysfs_create_file_ns(&cls->p->subsys.kobj,
- &attr->attr, ns);
- else
- error = -EINVAL;
+ if (!sp)
+ return -EINVAL;
+
+ error = sysfs_create_file_ns(&sp->subsys.kobj, &attr->attr, ns);
+ subsys_put(sp);
+
return error;
}
EXPORT_SYMBOL_GPL(class_create_file_ns);
@@ -162,8 +146,13 @@ EXPORT_SYMBOL_GPL(class_create_file_ns);
void class_remove_file_ns(const struct class *cls, const struct class_attribute *attr,
const void *ns)
{
- if (cls)
- sysfs_remove_file_ns(&cls->p->subsys.kobj, &attr->attr, ns);
+ struct subsys_private *sp = class_to_subsys(cls);
+
+ if (!sp)
+ return;
+
+ sysfs_remove_file_ns(&sp->subsys.kobj, &attr->attr, ns);
+ subsys_put(sp);
}
EXPORT_SYMBOL_GPL(class_remove_file_ns);
@@ -187,18 +176,6 @@ static void klist_class_dev_put(struct klist_node *n)
put_device(dev);
}
-static int class_add_groups(const struct class *cls,
- const struct attribute_group **groups)
-{
- return sysfs_create_groups(&cls->p->subsys.kobj, groups);
-}
-
-static void class_remove_groups(const struct class *cls,
- const struct attribute_group **groups)
-{
- return sysfs_remove_groups(&cls->p->subsys.kobj, groups);
-}
-
int class_register(struct class *cls)
{
struct subsys_private *cp;
@@ -235,8 +212,7 @@ int class_register(struct class *cls)
if (error)
goto err_out;
- error = class_add_groups(class_get(cls), cls->class_groups);
- class_put(cls);
+ error = sysfs_create_groups(&cp->subsys.kobj, cls->class_groups);
if (error) {
kobject_del(&cp->subsys.kobj);
kfree_const(cp->subsys.kobj.name);
@@ -253,9 +229,16 @@ EXPORT_SYMBOL_GPL(class_register);
void class_unregister(const struct class *cls)
{
+ struct subsys_private *sp = class_to_subsys(cls);
+
+ if (!sp)
+ return;
+
pr_debug("device class '%s': unregistering\n", cls->name);
- class_remove_groups(cls, cls->class_groups);
- kset_unregister(&cls->p->subsys);
+
+ sysfs_remove_groups(&sp->subsys.kobj, cls->class_groups);
+ kset_unregister(&sp->subsys);
+ subsys_put(sp);
}
EXPORT_SYMBOL_GPL(class_unregister);
@@ -334,11 +317,15 @@ EXPORT_SYMBOL_GPL(class_destroy);
void class_dev_iter_init(struct class_dev_iter *iter, const struct class *class,
const struct device *start, const struct device_type *type)
{
+ struct subsys_private *sp = class_to_subsys(class);
struct klist_node *start_knode = NULL;
+ if (!sp)
+ return;
+
if (start)
start_knode = &start->p->knode_class;
- klist_iter_init_node(&class->p->klist_devices, &iter->ki, start_knode);
+ klist_iter_init_node(&sp->klist_devices, &iter->ki, start_knode);
iter->type = type;
}
EXPORT_SYMBOL_GPL(class_dev_iter_init);
@@ -405,13 +392,14 @@ EXPORT_SYMBOL_GPL(class_dev_iter_exit);
int class_for_each_device(const struct class *class, const struct device *start,
void *data, int (*fn)(struct device *, void *))
{
+ struct subsys_private *sp = class_to_subsys(class);
struct class_dev_iter iter;
struct device *dev;
int error = 0;
if (!class)
return -EINVAL;
- if (!class->p) {
+ if (!sp) {
WARN(1, "%s called for class '%s' before it was initialized",
__func__, class->name);
return -EINVAL;
@@ -424,6 +412,7 @@ int class_for_each_device(const struct class *class, const struct device *start,
break;
}
class_dev_iter_exit(&iter);
+ subsys_put(sp);
return error;
}
@@ -453,12 +442,13 @@ struct device *class_find_device(const struct class *class, const struct device
const void *data,
int (*match)(struct device *, const void *))
{
+ struct subsys_private *sp = class_to_subsys(class);
struct class_dev_iter iter;
struct device *dev;
if (!class)
return NULL;
- if (!class->p) {
+ if (!sp) {
WARN(1, "%s called for class '%s' before it was initialized",
__func__, class->name);
return NULL;
@@ -472,6 +462,7 @@ struct device *class_find_device(const struct class *class, const struct device
}
}
class_dev_iter_exit(&iter);
+ subsys_put(sp);
return dev;
}
@@ -479,6 +470,7 @@ EXPORT_SYMBOL_GPL(class_find_device);
int class_interface_register(struct class_interface *class_intf)
{
+ struct subsys_private *sp;
const struct class *parent;
struct class_dev_iter iter;
struct device *dev;
@@ -486,19 +478,25 @@ int class_interface_register(struct class_interface *class_intf)
if (!class_intf || !class_intf->class)
return -ENODEV;
- parent = class_get(class_intf->class);
- if (!parent)
+ parent = class_intf->class;
+ sp = class_to_subsys(parent);
+ if (!sp)
return -EINVAL;
- mutex_lock(&parent->p->mutex);
- list_add_tail(&class_intf->node, &parent->p->interfaces);
+ /*
+ * Reference in sp is now incremented and will be dropped when
+ * the interface is removed in the call to class_interface_unregister()
+ */
+
+ mutex_lock(&sp->mutex);
+ list_add_tail(&class_intf->node, &sp->interfaces);
if (class_intf->add_dev) {
class_dev_iter_init(&iter, parent, NULL, NULL);
while ((dev = class_dev_iter_next(&iter)))
class_intf->add_dev(dev, class_intf);
class_dev_iter_exit(&iter);
}
- mutex_unlock(&parent->p->mutex);
+ mutex_unlock(&sp->mutex);
return 0;
}
@@ -506,6 +504,7 @@ EXPORT_SYMBOL_GPL(class_interface_register);
void class_interface_unregister(struct class_interface *class_intf)
{
+ struct subsys_private *sp;
struct class *parent = class_intf->class;
struct class_dev_iter iter;
struct device *dev;
@@ -513,7 +512,11 @@ void class_interface_unregister(struct class_interface *class_intf)
if (!parent)
return;
- mutex_lock(&parent->p->mutex);
+ sp = class_to_subsys(parent);
+ if (!sp)
+ return;
+
+ mutex_lock(&sp->mutex);
list_del_init(&class_intf->node);
if (class_intf->remove_dev) {
class_dev_iter_init(&iter, parent, NULL, NULL);
@@ -521,9 +524,15 @@ void class_interface_unregister(struct class_interface *class_intf)
class_intf->remove_dev(dev, class_intf);
class_dev_iter_exit(&iter);
}
- mutex_unlock(&parent->p->mutex);
+ mutex_unlock(&sp->mutex);
- class_put(parent);
+ /*
+ * Decrement the reference count twice, once for the class_to_subsys()
+ * call in the start of this function, and the second one from the
+ * reference increment in class_interface_register()
+ */
+ subsys_put(sp);
+ subsys_put(sp);
}
EXPORT_SYMBOL_GPL(class_interface_unregister);
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-26 05:25:12 +0000