Driver core: show drivers in /sys/module/

Show the drivers, which belong to the module:
  $ ls -l /sys/module/usbcore/drivers/
  hub -> ../../../bus/usb/drivers/hub
  usb -> ../../../bus/usb/drivers/usb
  usbfs -> ../../../bus/usb/drivers/usbfs

Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 25 insertions, 6 deletions

diff --git a/kernel/module.c b/kernel/module.c
index f0166563c602..45e01cb60101 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -1086,22 +1086,35 @@ static int mod_sysfs_setup(struct module *mod,
                 goto out;
         kobj_set_kset_s(&mod->mkobj, module_subsys);
         mod->mkobj.mod = mod;
-        err = kobject_register(&mod->mkobj.kobj);
+
+        /* delay uevent until full sysfs population */
+        kobject_init(&mod->mkobj.kobj);
+        err = kobject_add(&mod->mkobj.kobj);
         if (err)
                 goto out;
 
+        mod->drivers_dir = kobject_add_dir(&mod->mkobj.kobj, "drivers");
+        if (!mod->drivers_dir)
+                goto out_unreg;
+
         err = module_param_sysfs_setup(mod, kparam, num_params);
         if (err)
-                goto out_unreg;
+                goto out_unreg_drivers;
 
         err = module_add_modinfo_attrs(mod);
         if (err)
-                goto out_unreg;
+                goto out_unreg_param;
 
+        kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
         return 0;
 
+out_unreg_drivers:
+        kobject_unregister(mod->drivers_dir);
+out_unreg_param:
+        module_param_sysfs_remove(mod);
 out_unreg:
-        kobject_unregister(&mod->mkobj.kobj);
+        kobject_del(&mod->mkobj.kobj);
+        kobject_put(&mod->mkobj.kobj);
 out:
         return err;
 }
@@ -1110,6 +1123,7 @@ static void mod_kobject_remove(struct module *mod)
 {
         module_remove_modinfo_attrs(mod);
         module_param_sysfs_remove(mod);
+        kobject_unregister(mod->drivers_dir);
 
         kobject_unregister(&mod->mkobj.kobj);
 }
@@ -2275,11 +2289,14 @@ void print_modules(void)
 
 void module_add_driver(struct module *mod, struct device_driver *drv)
 {
+        int no_warn;
+
         if (!mod || !drv)
                 return;
 
-        /* Don't check return code; this call is idempotent */
-        sysfs_create_link(&drv->kobj, &mod->mkobj.kobj, "module");
+        /* Don't check return codes; these calls are idempotent */
+        no_warn = sysfs_create_link(&drv->kobj, &mod->mkobj.kobj, "module");
+        no_warn = sysfs_create_link(mod->drivers_dir, &drv->kobj, drv->name);
 }
 EXPORT_SYMBOL(module_add_driver);
 
@@ -2288,6 +2305,8 @@ void module_remove_driver(struct device_driver *drv)
         if (!drv)
                 return;
         sysfs_remove_link(&drv->kobj, "module");
+        if (drv->owner && drv->owner->drivers_dir)
+                sysfs_remove_link(drv->owner->drivers_dir, drv->name);
 }
 EXPORT_SYMBOL(module_remove_driver);