/sys/modules/*/holders

  /sys/module/usbcore/
  |-- drivers
  |   |-- usb:hub -> ../../../subsystem/usb/drivers/hub
  |   |-- usb:usb -> ../../../subsystem/usb/drivers/usb
  |   `-- usb:usbfs -> ../../../subsystem/usb/drivers/usbfs
  |-- holders
  |   |-- ehci_hcd -> ../../../module/ehci_hcd
  |   |-- uhci_hcd -> ../../../module/uhci_hcd
  |   |-- usb_storage -> ../../../module/usb_storage
  |   `-- usbhid -> ../../../module/usbhid
  |-- initstate

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

diff --git a/include/linux/module.h b/include/linux/module.h
index 90dc2542978ca73d7787f7bd1e9d05501220ab78..419d3ef293dd996ba4ee3fda9501feebdd13e0aa 100644 (file)
--- a/include/linux/module.h
+++ b/include/linux/module.h
@@ -264,6 +264,7 @@ struct module
        struct module_attribute *modinfo_attrs;
        const char *version;
        const char *srcversion;
+       struct kobject *holders_dir;
 
        /* Exported symbols */
        const struct kernel_symbol *syms;

diff --git a/kernel/module.c b/kernel/module.c
index 9de4209f6a67ff5eba1e50c707d19373224a9a7a..8a94e054230c07abb5371c8e8b4e369f3e8476bd 100644 (file)
--- 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;
 
@@ -1125,15 +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->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)
@@ -1144,7 +1161,9 @@ static int mod_sysfs_setup(struct module *mod,
 
 out_unreg_param:
        module_param_sysfs_remove(mod);
-out_unreg_drivers:
+out_unreg_holders:
+       kobject_unregister(mod->holders_dir);
+out_unreg:
        kobject_del(&mod->mkobj.kobj);
        kobject_put(&mod->mkobj.kobj);
 out:
@@ -1157,6 +1176,8 @@ static void mod_kobject_remove(struct module *mod)
        module_param_sysfs_remove(mod);
        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);
 }
@@ -1761,6 +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"));
 

diff --git a/kernel/params.c b/kernel/params.c
index cbaac85942d5a3fba3856db6908804a12baaf4eb..553cf7d6a4be113f0dcb89f1be51aa9989d51453 100644 (file)
--- a/kernel/params.c
+++ b/kernel/params.c
@@ -30,6 +30,8 @@
 #define DEBUGP(fmt, a...)
 #endif
 
+static struct kobj_type module_ktype;
+
 static inline char dash2underscore(char c)
 {
        if (c == '-')
@@ -671,6 +673,19 @@ static struct sysfs_ops module_sysfs_ops = {
        .store = module_attr_store,
 };
 
+static int uevent_filter(struct kset *kset, struct kobject *kobj)
+{
+       struct kobj_type *ktype = get_ktype(kobj);
+
+       if (ktype == &module_ktype)
+               return 1;
+       return 0;
+}
+
+static struct kset_uevent_ops module_uevent_ops = {
+       .filter = uevent_filter,
+};
+
 #else
 static struct sysfs_ops module_sysfs_ops = {
        .show = NULL,
@@ -682,7 +697,7 @@ static struct kobj_type module_ktype = {
        .sysfs_ops =    &module_sysfs_ops,
 };
 
-decl_subsys(module, &module_ktype, NULL);
+decl_subsys(module, &module_ktype, &module_uevent_ops);
 
 /*
  * param_sysfs_init - wrapper for built-in params support