efivars: Split out variable registration

In anticipation of re-using the variable facilities in efivars from
elsewhere, split out the registration and unregistration of struct
efivars from the rest of the EFI specific sysfs code.

Signed-off-by: Mike Waychison <mikew@google.com>
Cc: Matt Domsch <Matt_Domsch@dell.com>,
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/firmware/efivars.c b/drivers/firmware/efivars.c
index 5633018..f22bfcf 100644 (file)
--- a/drivers/firmware/efivars.c
+++ b/drivers/firmware/efivars.c
@@ -95,7 +95,7 @@ struct efivars {
         * 1) ->list - adds, removals, reads, writes
         * 2) efi.[gs]et_variable() calls.
         * It must not be held when creating sysfs entries or calling kmalloc.
-        * efi.get_next_variable() is only called from efivars_init(),
+        * efi.get_next_variable() is only called from register_efivars(),
         * which is protected by the BKL, so that path is safe.
         */
        spinlock_t lock;
@@ -699,54 +699,48 @@ out_free:
        return error;
 }
 
-static struct efivars __efivars;
+static void unregister_efivars(struct efivars *efivars)
+{
+       struct efivar_entry *entry, *n;
 
-/*
- * For now we register the efi subsystem with the firmware subsystem
- * and the vars subsystem with the efi subsystem.  In the future, it
- * might make sense to split off the efi subsystem into its own
- * driver, but for now only efivars will register with it, so just
- * include it here.
- */
+       list_for_each_entry_safe(entry, n, &efivars->list, list) {
+               spin_lock(&efivars->lock);
+               list_del(&entry->list);
+               spin_unlock(&efivars->lock);
+               efivar_unregister(entry);
+       }
+       if (efivars->new_var)
+               sysfs_remove_bin_file(&efivars->kset->kobj, efivars->new_var);
+       if (efivars->del_var)
+               sysfs_remove_bin_file(&efivars->kset->kobj, efivars->del_var);
+       kfree(efivars->new_var);
+       kfree(efivars->del_var);
+       kset_unregister(efivars->kset);
+}
 
-static int __init
-efivars_init(void)
+static int register_efivars(struct efivars *efivars,
+                           struct kobject *parent_kobj)
 {
        efi_status_t status = EFI_NOT_FOUND;
        efi_guid_t vendor_guid;
        efi_char16_t *variable_name;
        unsigned long variable_name_size = 1024;
-       struct efivars *efivars = &__efivars;
        int error = 0;
 
-       if (!efi_enabled)
-               return -ENODEV;
-
        variable_name = kzalloc(variable_name_size, GFP_KERNEL);
        if (!variable_name) {
                printk(KERN_ERR "efivars: Memory allocation failed.\n");
                return -ENOMEM;
        }
 
-       printk(KERN_INFO "EFI Variables Facility v%s %s\n", EFIVARS_VERSION,
-              EFIVARS_DATE);
-
-       /* For now we'll register the efi directory at /sys/firmware/efi */
-       efi_kobj = kobject_create_and_add("efi", firmware_kobj);
-       if (!efi_kobj) {
-               printk(KERN_ERR "efivars: Firmware registration failed.\n");
-               error = -ENOMEM;
-               goto out_free;
-       }
-
        spin_lock_init(&efivars->lock);
        INIT_LIST_HEAD(&efivars->list);
 
-       efivars->kset = kset_create_and_add("vars", NULL, efi_kobj);
+       efivars->kset = kset_create_and_add("vars", NULL, parent_kobj);
        if (!efivars->kset) {
                printk(KERN_ERR "efivars: Subsystem registration failed.\n");
                error = -ENOMEM;
-               goto out_firmware_unregister;
+               goto out;
        }
 
        /*
@@ -778,21 +772,54 @@ efivars_init(void)
        } while (status != EFI_NOT_FOUND);
 
        error = create_efivars_bin_attributes(efivars);
-
-       /* Don't forget the systab entry */
-       error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group);
        if (error)
-               printk(KERN_ERR "efivars: Sysfs attribute export failed with error %d.\n", error);
-       else
-               goto out_free;
+               unregister_efivars(efivars);
 
-       kset_unregister(efivars->kset);
+out:
+       kfree(variable_name);
 
-out_firmware_unregister:
-       kobject_put(efi_kobj);
+       return error;
+}
 
-out_free:
-       kfree(variable_name);
+static struct efivars __efivars;
+
+/*
+ * For now we register the efi subsystem with the firmware subsystem
+ * and the vars subsystem with the efi subsystem.  In the future, it
+ * might make sense to split off the efi subsystem into its own
+ * driver, but for now only efivars will register with it, so just
+ * include it here.
+ */
+
+static int __init
+efivars_init(void)
+{
+       int error = 0;
+
+       printk(KERN_INFO "EFI Variables Facility v%s %s\n", EFIVARS_VERSION,
+              EFIVARS_DATE);
+
+       if (!efi_enabled)
+               return -ENODEV;
+
+       /* For now we'll register the efi directory at /sys/firmware/efi */
+       efi_kobj = kobject_create_and_add("efi", firmware_kobj);
+       if (!efi_kobj) {
+               printk(KERN_ERR "efivars: Firmware registration failed.\n");
+               return -ENOMEM;
+       }
+
+       error = register_efivars(&__efivars, efi_kobj);
+
+       /* Don't forget the systab entry */
+       error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group);
+       if (error) {
+               printk(KERN_ERR
+                      "efivars: Sysfs attribute export failed with error %d.\n",
+                      error);
+               unregister_efivars(&__efivars);
+               kobject_put(efi_kobj);
+       }
 
        return error;
 }
@@ -800,22 +827,7 @@ out_free:
 static void __exit
 efivars_exit(void)
 {
-       struct efivars *efivars = &__efivars;
-       struct efivar_entry *entry, *n;
-
-       list_for_each_entry_safe(entry, n, &efivars->list, list) {
-               spin_lock(&efivars->lock);
-               list_del(&entry->list);
-               spin_unlock(&efivars->lock);
-               efivar_unregister(entry);
-       }
-       if (efivars->new_var)
-               sysfs_remove_bin_file(&efivars->kset->kobj, efivars->new_var);
-       if (efivars->del_var)
-               sysfs_remove_bin_file(&efivars->kset->kobj, efivars->del_var);
-       kfree(efivars->new_var);
-       kfree(efivars->del_var);
-       kset_unregister(efivars->kset);
+       unregister_efivars(&__efivars);
        kobject_put(efi_kobj);
 }