cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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module.c (2074B)


      1// SPDX-License-Identifier: GPL-2.0
      2/*
      3 * module.c - module sysfs fun for drivers
      4 */
      5#include <linux/device.h>
      6#include <linux/module.h>
      7#include <linux/errno.h>
      8#include <linux/slab.h>
      9#include <linux/string.h>
     10#include "base.h"
     11
     12static char *make_driver_name(struct device_driver *drv)
     13{
     14	char *driver_name;
     15
     16	driver_name = kasprintf(GFP_KERNEL, "%s:%s", drv->bus->name, drv->name);
     17	if (!driver_name)
     18		return NULL;
     19
     20	return driver_name;
     21}
     22
     23static void module_create_drivers_dir(struct module_kobject *mk)
     24{
     25	static DEFINE_MUTEX(drivers_dir_mutex);
     26
     27	mutex_lock(&drivers_dir_mutex);
     28	if (mk && !mk->drivers_dir)
     29		mk->drivers_dir = kobject_create_and_add("drivers", &mk->kobj);
     30	mutex_unlock(&drivers_dir_mutex);
     31}
     32
     33void module_add_driver(struct module *mod, struct device_driver *drv)
     34{
     35	char *driver_name;
     36	int no_warn;
     37	struct module_kobject *mk = NULL;
     38
     39	if (!drv)
     40		return;
     41
     42	if (mod)
     43		mk = &mod->mkobj;
     44	else if (drv->mod_name) {
     45		struct kobject *mkobj;
     46
     47		/* Lookup built-in module entry in /sys/modules */
     48		mkobj = kset_find_obj(module_kset, drv->mod_name);
     49		if (mkobj) {
     50			mk = container_of(mkobj, struct module_kobject, kobj);
     51			/* remember our module structure */
     52			drv->p->mkobj = mk;
     53			/* kset_find_obj took a reference */
     54			kobject_put(mkobj);
     55		}
     56	}
     57
     58	if (!mk)
     59		return;
     60
     61	/* Don't check return codes; these calls are idempotent */
     62	no_warn = sysfs_create_link(&drv->p->kobj, &mk->kobj, "module");
     63	driver_name = make_driver_name(drv);
     64	if (driver_name) {
     65		module_create_drivers_dir(mk);
     66		no_warn = sysfs_create_link(mk->drivers_dir, &drv->p->kobj,
     67					    driver_name);
     68		kfree(driver_name);
     69	}
     70}
     71
     72void module_remove_driver(struct device_driver *drv)
     73{
     74	struct module_kobject *mk = NULL;
     75	char *driver_name;
     76
     77	if (!drv)
     78		return;
     79
     80	sysfs_remove_link(&drv->p->kobj, "module");
     81
     82	if (drv->owner)
     83		mk = &drv->owner->mkobj;
     84	else if (drv->p->mkobj)
     85		mk = drv->p->mkobj;
     86	if (mk && mk->drivers_dir) {
     87		driver_name = make_driver_name(drv);
     88		if (driver_name) {
     89			sysfs_remove_link(mk->drivers_dir, driver_name);
     90			kfree(driver_name);
     91		}
     92	}
     93}