[PATCH v2] efi/efivars: Create efivars mount point via efivars abstraction

[Lee, Chun-Yi]

This patch creates efivars mount point when active efivars abstraction
be set. It is useful for userland to determine the availability of efivars
filesystem.

v2:
Using efivars_kobject() helper instead of checking GetVariable or
GetNextVariable EFI runtime services. Because the efivarfs code could be
instantiated using a different efivars abstraction.

Cc: Matthias Brugger <mbrugger@xxxxxxxx>
Cc: Fabian Vogt <fvogt@xxxxxxxx>
Cc: Ilias Apalodimas <ilias.apalodimas@xxxxxxxxxx>
Cc: Ard Biesheuvel <ardb@xxxxxxxxxx>
Signed-off-by: "Lee, Chun-Yi" <jlee@xxxxxxxx>
---
 drivers/firmware/efi/efi.c | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c
index 3aa07c3b5136..db483fc68501 100644
--- a/drivers/firmware/efi/efi.c
+++ b/drivers/firmware/efi/efi.c
@@ -405,11 +405,13 @@ static int __init efisubsys_init(void)
 	if (error)
 		goto err_remove_group;
 
-	/* and the standard mountpoint for efivarfs */
-	error = sysfs_create_mount_point(efi_kobj, "efivars");
-	if (error) {
-		pr_err("efivars: Subsystem registration failed.\n");
-		goto err_remove_group;
+	if (efivars_kobject()) {
+		/* and the standard mountpoint for efivarfs */
+		error = sysfs_create_mount_point(efi_kobj, "efivars");
+		if (error) {
+			pr_err("efivars: Subsystem registration failed.\n");
+			goto err_remove_group;
+		}
 	}
 
 	if (efi_enabled(EFI_DBG) && efi_enabled(EFI_PRESERVE_BS_REGIONS))
-- 
2.16.4