open_volume 432 drivers/firmware/efi/libstub/efi-stub-helper.c status = efi_call_proto(efi_file_io_interface, open_volume, io, &fh); open_volume 921 include/linux/efi.h u32 open_volume; open_volume 926 include/linux/efi.h u64 open_volume; open_volume 931 include/linux/efi.h int (*open_volume)(struct _efi_file_io_interface *,