+#define to_module_attr(n) container_of(n, struct module_attribute, attr);
+
+static ssize_t module_attr_show(struct kobject *kobj,
+ struct attribute *attr,
+ char *buf)
+{
+ int count;
+ struct module_attribute *attribute = to_module_attr(attr);
+
+ if (!attribute->param->get)
+ return -EPERM;
+
+ count = attribute->param->get(buf, attribute->param);
+ if (count > 0) {
+ strcat(buf, "\n");
+ ++count;
+ }
+ return count;
+}
+
+/* sysfs always hands a nul-terminated string in buf. We rely on that. */
+static ssize_t module_attr_store(struct kobject *kobj,
+ struct attribute *attr,
+ const char *buf, size_t len)
+{
+ int err;
+ struct module_attribute *attribute = to_module_attr(attr);
+
+ if (!attribute->param->set)
+ return -EPERM;
+
+ err = attribute->param->set(buf, attribute->param);
+ if (!err)
+ return len;
+ return err;
+}
+
+static struct sysfs_ops module_sysfs_ops = {
+ .show = module_attr_show,
+ .store = module_attr_store,
+};
+
+static void module_kobj_release(struct kobject *kobj)
+{
+ kfree(container_of(kobj, struct module_kobject, kobj));
+}
+
+static struct kobj_type module_ktype = {
+ .sysfs_ops = &module_sysfs_ops,
+ .release = &module_kobj_release,
+};
+static decl_subsys(module, &module_ktype, NULL);
+
+static int mod_sysfs_setup(struct module *mod,
+ struct kernel_param *kparam,
+ unsigned int num_params)
+{
+ unsigned int i;
+ int err;
+
+ /* We overallocate: not every param is in sysfs, and maybe no refcnt */
+ mod->mkobj = kmalloc(sizeof(*mod->mkobj)
+ + sizeof(mod->mkobj->attr[0]) * (num_params+1),
+ GFP_KERNEL);
+ if (!mod->mkobj)
+ return -ENOMEM;
+
+ memset(&mod->mkobj->kobj, 0, sizeof(mod->mkobj->kobj));
+ err = kobject_set_name(&mod->mkobj->kobj, mod->name);
+ if (err)
+ goto out;
+ kobj_set_kset_s(mod->mkobj, module_subsys);
+ err = kobject_register(&mod->mkobj->kobj);
+ if (err)
+ goto out;
+
+ mod->mkobj->num_attributes = 0;
+
+ for (i = 0; i < num_params; i++) {
+ if (kparam[i].perm) {
+ err = add_attribute(mod, &kparam[i]);
+ if (err)
+ goto out_unreg;
+ }
+ }
+ err = sysfs_unload_setup(mod);
+ if (err)
+ goto out_unreg;
+ return 0;
+
+out_unreg:
+ for (i = 0; i < mod->mkobj->num_attributes; i++)
+ sysfs_remove_file(&mod->mkobj->kobj,&mod->mkobj->attr[i].attr);
+ /* Calls module_kobj_release */
+ kobject_unregister(&mod->mkobj->kobj);
+ return err;
+out:
+ kfree(mod->mkobj);
+ return err;
+}
+
+static void mod_kobject_remove(struct module *mod)
+{
+ unsigned int i;
+ for (i = 0; i < mod->mkobj->num_attributes; i++)
+ sysfs_remove_file(&mod->mkobj->kobj,&mod->mkobj->attr[i].attr);
+ /* Calls module_kobj_release */
+ kobject_unregister(&mod->mkobj->kobj);
+}
+