1 files changed, 59 insertions, 17 deletions

diff --git a/kernel/module.c b/kernel/module.c
index d0f2260a0210..8a94e054230c 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -537,6 +537,8 @@ static int already_uses(struct module *a, struct module *b)
 static int use_module(struct module *a, struct module *b)
 {
         struct module_use *use;
+        int no_warn;
+
         if (b == NULL || already_uses(a, b)) return 1;
 
         if (!strong_try_module_get(b))
@@ -552,6 +554,7 @@ static int use_module(struct module *a, struct module *b)
 
         use->module_which_uses = a;
         list_add(&use->list, &b->modules_which_use_me);
+        no_warn = sysfs_create_link(b->holders_dir, &a->mkobj.kobj, a->name);
         return 1;
 }
 
@@ -569,6 +572,7 @@ static void module_unload_free(struct module *mod)
                                 module_put(i);
                                 list_del(&use->list);
                                 kfree(use);
+                                sysfs_remove_link(i->holders_dir, mod->name);
                                 /* There can be at most one match. */
                                 break;
                         }
@@ -1106,9 +1110,7 @@ static void module_remove_modinfo_attrs(struct module *mod)
         kfree(mod->modinfo_attrs);
 }
 
-static int mod_sysfs_setup(struct module *mod,
-                           struct kernel_param *kparam,
-                           unsigned int num_params)
+static int mod_sysfs_init(struct module *mod)
 {
         int err;
 
@@ -1125,21 +1127,30 @@ static int mod_sysfs_setup(struct module *mod,
         kobj_set_kset_s(&mod->mkobj, module_subsys);
         mod->mkobj.mod = mod;
 
-        /* delay uevent until full sysfs population */
         kobject_init(&mod->mkobj.kobj);
+
+out:
+        return err;
+}
+
+static int mod_sysfs_setup(struct module *mod,
+                           struct kernel_param *kparam,
+                           unsigned int num_params)
+{
+        int err;
+
+        /* delay uevent until full sysfs population */
         err = kobject_add(&mod->mkobj.kobj);
         if (err)
                 goto out;
 
-        mod->drivers_dir = kobject_add_dir(&mod->mkobj.kobj, "drivers");
-        if (!mod->drivers_dir) {
-                err = -ENOMEM;
+        mod->holders_dir = kobject_add_dir(&mod->mkobj.kobj, "holders");
+        if (!mod->holders_dir)
                 goto out_unreg;
-        }
 
         err = module_param_sysfs_setup(mod, kparam, num_params);
         if (err)
-                goto out_unreg_drivers;
+                goto out_unreg_holders;
 
         err = module_add_modinfo_attrs(mod);
         if (err)
@@ -1150,8 +1161,8 @@ static int mod_sysfs_setup(struct module *mod,
 
 out_unreg_param:
         module_param_sysfs_remove(mod);
-out_unreg_drivers:
-        kobject_unregister(mod->drivers_dir);
+out_unreg_holders:
+        kobject_unregister(mod->holders_dir);
 out_unreg:
         kobject_del(&mod->mkobj.kobj);
         kobject_put(&mod->mkobj.kobj);
@@ -1163,7 +1174,10 @@ static void mod_kobject_remove(struct module *mod)
 {
         module_remove_modinfo_attrs(mod);
         module_param_sysfs_remove(mod);
-        kobject_unregister(mod->drivers_dir);
+        if (mod->mkobj.drivers_dir)
+                kobject_unregister(mod->mkobj.drivers_dir);
+        if (mod->holders_dir)
+                kobject_unregister(mod->holders_dir);
 
         kobject_unregister(&mod->mkobj.kobj);
 }
@@ -1768,6 +1782,10 @@ static struct module *load_module(void __user *umod,
         /* Now we've moved module, initialize linked lists, etc. */
         module_unload_init(mod);
 
+        /* Initialize kobject, so we can reference it. */
+        if (mod_sysfs_init(mod) != 0)
+                goto cleanup;
+
         /* Set up license info based on the info section */
         set_license(mod, get_modinfo(sechdrs, infoindex, "license"));
 
@@ -2340,19 +2358,43 @@ 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;
         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_subsys.kset, drv->mod_name);
+                if (mkobj)
+                        mk = container_of(mkobj, struct module_kobject, kobj);
+        }
 
-        if (!mod || !drv)
+        if (!mk)
                 return;
 
         /* 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(&drv->kobj, &mk->kobj, "module");
         driver_name = make_driver_name(drv);
         if (driver_name) {
-                no_warn = sysfs_create_link(mod->drivers_dir, &drv->kobj,
+                module_create_drivers_dir(mk);
+                no_warn = sysfs_create_link(mk->drivers_dir, &drv->kobj,
                                             driver_name);
                 kfree(driver_name);
         }
@@ -2367,10 +2409,10 @@ void module_remove_driver(struct device_driver *drv)
                 return;
 
         sysfs_remove_link(&drv->kobj, "module");
-        if (drv->owner && drv->owner->drivers_dir) {
+        if (drv->owner && drv->owner->mkobj.drivers_dir) {
                 driver_name = make_driver_name(drv);
                 if (driver_name) {
-                        sysfs_remove_link(drv->owner->drivers_dir,
+                        sysfs_remove_link(drv->owner->mkobj.drivers_dir,
                                           driver_name);
                         kfree(driver_name);
                 }