Modules: only add drivers/ direcory if needed

This changes the module core to only create the drivers/ directory if we
are going to put something in it.

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

2 files changed, 11 insertions, 10 deletions

diff --git a/kernel/module.c b/kernel/module.c
index 0f4489af3e2..9de4209f6a6 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -1131,12 +1131,6 @@ static int mod_sysfs_setup(struct module *mod,
         if (err)
                 goto out;
 
-        mod->mkobj.drivers_dir = kobject_add_dir(&mod->mkobj.kobj, "drivers");
-        if (!mod->mkobj.drivers_dir) {
-                err = -ENOMEM;
-                goto out_unreg;
-        }
-
         err = module_param_sysfs_setup(mod, kparam, num_params);
         if (err)
                 goto out_unreg_drivers;
@@ -1151,8 +1145,6 @@ static int mod_sysfs_setup(struct module *mod,
 out_unreg_param:
         module_param_sysfs_remove(mod);
 out_unreg_drivers:
-        kobject_unregister(mod->mkobj.drivers_dir);
-out_unreg:
         kobject_del(&mod->mkobj.kobj);
         kobject_put(&mod->mkobj.kobj);
 out:
@@ -1163,7 +1155,8 @@ static void mod_kobject_remove(struct module *mod)
 {
         module_remove_modinfo_attrs(mod);
         module_param_sysfs_remove(mod);
-        kobject_unregister(mod->mkobj.drivers_dir);
+        if (mod->mkobj.drivers_dir)
+                kobject_unregister(mod->mkobj.drivers_dir);
 
         kobject_unregister(&mod->mkobj.kobj);
 }
@@ -2340,6 +2333,14 @@ static char *make_driver_name(struct device_driver *drv)
         return driver_name;
 }
 
+static void module_create_drivers_dir(struct module_kobject *mk)
+{
+        if (!mk || mk->drivers_dir)
+                return;
+
+        mk->drivers_dir = kobject_add_dir(&mk->kobj, "drivers");
+}
+
 void module_add_driver(struct module *mod, struct device_driver *drv)
 {
         char *driver_name;
@@ -2367,6 +2368,7 @@ void module_add_driver(struct module *mod, struct device_driver *drv)
         no_warn = sysfs_create_link(&drv->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->kobj,
                                             driver_name);
                 kfree(driver_name);
diff --git a/kernel/params.c b/kernel/params.c
index 737b7c5e93a..cbaac85942d 100644
--- a/kernel/params.c
+++ b/kernel/params.c
@@ -565,7 +565,6 @@ static void __init kernel_param_sysfs_setup(const char *name,
         ret = kobject_add(&mk->kobj);
         BUG_ON(ret < 0);
         param_sysfs_setup(mk, kparam, num_params, name_skip);
-        mk->drivers_dir = kobject_add_dir(&mk->kobj, "drivers");
         kobject_uevent(&mk->kobj, KOBJ_ADD);
 }