linux/drivers/base/module.c
Greg Kroah-Hartman 67c1ba551e driver core: module: make module_[add|remove]_driver take a const *
The functions module_add_driver() and module_remove_driver() do not
modify the struct device_driver structure directly, so they are safe to
be marked as a constant pointer type.

Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Link: https://lore.kernel.org/r/2024070850-entering-grandson-205e@gregkh
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-07-10 09:46:02 +02:00

114 lines
2.2 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* module.c - module sysfs fun for drivers
*/
#include <linux/device.h>
#include <linux/module.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/string.h>
#include "base.h"
static char *make_driver_name(const struct device_driver *drv)
{
char *driver_name;
driver_name = kasprintf(GFP_KERNEL, "%s:%s", drv->bus->name, drv->name);
if (!driver_name)
return NULL;
return driver_name;
}
static void module_create_drivers_dir(struct module_kobject *mk)
{
static DEFINE_MUTEX(drivers_dir_mutex);
mutex_lock(&drivers_dir_mutex);
if (mk && !mk->drivers_dir)
mk->drivers_dir = kobject_create_and_add("drivers", &mk->kobj);
mutex_unlock(&drivers_dir_mutex);
}
int module_add_driver(struct module *mod, const struct device_driver *drv)
{
char *driver_name;
struct module_kobject *mk = NULL;
int ret;
if (!drv)
return 0;
if (mod)
mk = &mod->mkobj;
else if (drv->mod_name) {
struct kobject *mkobj;
/* Lookup built-in module entry in /sys/modules */
mkobj = kset_find_obj(module_kset, drv->mod_name);
if (mkobj) {
mk = container_of(mkobj, struct module_kobject, kobj);
/* remember our module structure */
drv->p->mkobj = mk;
/* kset_find_obj took a reference */
kobject_put(mkobj);
}
}
if (!mk)
return 0;
ret = sysfs_create_link(&drv->p->kobj, &mk->kobj, "module");
if (ret)
return ret;
driver_name = make_driver_name(drv);
if (!driver_name) {
ret = -ENOMEM;
goto out;
}
module_create_drivers_dir(mk);
if (!mk->drivers_dir) {
ret = -EINVAL;
goto out;
}
ret = sysfs_create_link(mk->drivers_dir, &drv->p->kobj, driver_name);
if (ret)
goto out;
kfree(driver_name);
return 0;
out:
sysfs_remove_link(&drv->p->kobj, "module");
sysfs_remove_link(mk->drivers_dir, driver_name);
kfree(driver_name);
return ret;
}
void module_remove_driver(const struct device_driver *drv)
{
struct module_kobject *mk = NULL;
char *driver_name;
if (!drv)
return;
sysfs_remove_link(&drv->p->kobj, "module");
if (drv->owner)
mk = &drv->owner->mkobj;
else if (drv->p->mkobj)
mk = drv->p->mkobj;
if (mk && mk->drivers_dir) {
driver_name = make_driver_name(drv);
if (driver_name) {
sysfs_remove_link(mk->drivers_dir, driver_name);
kfree(driver_name);
}
}
}