[PATCH 2/5] driver core: class: make class_register() take a const *

From: Greg Kroah-Hartman
Date: Sun Apr 02 2023 - 13:59:31 EST


Now that the class code is cleaned up to not modify the class pointer
registered with it, change class_register() to take a const * to allow
the structure to be placed into read-only memory.

Cc: "Rafael J. Wysocki" <rafael@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/base/base.h | 2 +-
drivers/base/class.c | 6 +++---
include/linux/device/class.h | 2 +-
3 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/base/base.h b/drivers/base/base.h
index e96f3343fd7c..eb4c0ace9242 100644
--- a/drivers/base/base.h
+++ b/drivers/base/base.h
@@ -54,7 +54,7 @@ struct subsys_private {
struct device *dev_root;

struct kset glue_dirs;
- struct class *class;
+ const struct class *class;

struct lock_class_key lock_key;
};
diff --git a/drivers/base/class.c b/drivers/base/class.c
index 53fc7052340c..05bce79d3d19 100644
--- a/drivers/base/class.c
+++ b/drivers/base/class.c
@@ -93,7 +93,7 @@ static ssize_t class_attr_store(struct kobject *kobj, struct attribute *attr,
static void class_release(struct kobject *kobj)
{
struct subsys_private *cp = to_subsys_private(kobj);
- struct class *class = cp->class;
+ const struct class *class = cp->class;

pr_debug("class '%s': release.\n", class->name);

@@ -110,7 +110,7 @@ static void class_release(struct kobject *kobj)
static const struct kobj_ns_type_operations *class_child_ns_type(const struct kobject *kobj)
{
const struct subsys_private *cp = to_subsys_private(kobj);
- struct class *class = cp->class;
+ const struct class *class = cp->class;

return class->ns_type;
}
@@ -175,7 +175,7 @@ static void klist_class_dev_put(struct klist_node *n)
put_device(dev);
}

-int class_register(struct class *cls)
+int class_register(const struct class *cls)
{
struct subsys_private *cp;
struct lock_class_key *key;
diff --git a/include/linux/device/class.h b/include/linux/device/class.h
index f3c418fa129a..4bf46f9bbb56 100644
--- a/include/linux/device/class.h
+++ b/include/linux/device/class.h
@@ -76,7 +76,7 @@ struct class_dev_iter {
const struct device_type *type;
};

-int __must_check class_register(struct class *class);
+int __must_check class_register(const struct class *class);
void class_unregister(const struct class *class);
bool class_is_registered(const struct class *class);

--
2.40.0