// 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(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); } void module_add_driver(struct module *mod, struct device_driver *drv) { char *driver_name; int no_warn; struct module_kobject *mk = NULL; if (!drv) return; 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; /* Don't check return codes; these calls are idempotent */ no_warn = sysfs_create_link(&drv->p->kobj, &mk->kobj, "module"); driver_name = make_driver_name(drv); if (driver_name) { module_create_drivers_dir(mk); no_warn = sysfs_create_link(mk->drivers_dir, &drv->p->kobj, driver_name); kfree(driver_name); } } void module_remove_driver(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); } } }