Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
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 <linux/rcupdate.h>
11#include "base.h"
12
13static char *make_driver_name(const struct device_driver *drv)
14{
15 char *driver_name;
16
17 driver_name = kasprintf(GFP_KERNEL, "%s:%s", drv->bus->name, drv->name);
18 if (!driver_name)
19 return NULL;
20
21 return driver_name;
22}
23
24static void module_create_drivers_dir(struct module_kobject *mk)
25{
26 static DEFINE_MUTEX(drivers_dir_mutex);
27
28 mutex_lock(&drivers_dir_mutex);
29 if (mk && !mk->drivers_dir)
30 mk->drivers_dir = kobject_create_and_add("drivers", &mk->kobj);
31 mutex_unlock(&drivers_dir_mutex);
32}
33
34int module_add_driver(struct module *mod, const struct device_driver *drv)
35{
36 char *driver_name;
37 struct module_kobject *mk = NULL;
38 int ret;
39
40 if (!drv)
41 return 0;
42
43 if (mod)
44 mk = &mod->mkobj;
45 else if (drv->mod_name) {
46 struct kobject *mkobj;
47
48 /* Lookup built-in module entry in /sys/modules */
49 mkobj = kset_find_obj(module_kset, drv->mod_name);
50 if (mkobj) {
51 mk = container_of(mkobj, struct module_kobject, kobj);
52 /* remember our module structure */
53 drv->p->mkobj = mk;
54 /* kset_find_obj took a reference */
55 kobject_put(mkobj);
56 }
57 }
58
59 if (!mk)
60 return 0;
61
62 ret = sysfs_create_link(&drv->p->kobj, &mk->kobj, "module");
63 if (ret)
64 return ret;
65
66 driver_name = make_driver_name(drv);
67 if (!driver_name) {
68 ret = -ENOMEM;
69 goto out;
70 }
71
72 module_create_drivers_dir(mk);
73 if (!mk->drivers_dir) {
74 ret = -EINVAL;
75 goto out;
76 }
77
78 ret = sysfs_create_link(mk->drivers_dir, &drv->p->kobj, driver_name);
79 if (ret)
80 goto out;
81
82 kfree(driver_name);
83
84 return 0;
85out:
86 sysfs_remove_link(&drv->p->kobj, "module");
87 sysfs_remove_link(mk->drivers_dir, driver_name);
88 kfree(driver_name);
89
90 return ret;
91}
92
93void module_remove_driver(const struct device_driver *drv)
94{
95 struct module_kobject *mk = NULL;
96 char *driver_name;
97
98 if (!drv)
99 return;
100
101 /* Synchronize with dev_uevent() */
102 synchronize_rcu();
103
104 sysfs_remove_link(&drv->p->kobj, "module");
105
106 if (drv->owner)
107 mk = &drv->owner->mkobj;
108 else if (drv->p->mkobj)
109 mk = drv->p->mkobj;
110 if (mk && mk->drivers_dir) {
111 driver_name = make_driver_name(drv);
112 if (driver_name) {
113 sysfs_remove_link(mk->drivers_dir, driver_name);
114 kfree(driver_name);
115 }
116 }
117}