// SPDX-License-Identifier: GPL-2.0+
/*
 * UEFI runtime variable services
 *
 * Copyright (c) 2020, Heinrich Schuchardt <xypron.glpk@gmx.de>
 */

#include <common.h>
#include <efi_loader.h>
#include <efi_variable.h>

/**
 * efi_efi_get_variable() - retrieve value of a UEFI variable
 *
 * This function implements the GetVariable runtime service.
 *
 * See the Unified Extensible Firmware Interface (UEFI) specification for
 * details.
 *
 * @variable_name:	name of the variable
 * @vendor:		vendor GUID
 * @attributes:		attributes of the variable
 * @data_size:		size of the buffer to which the variable value is copied
 * @data:		buffer to which the variable value is copied
 * Return:		status code
 */
efi_status_t EFIAPI efi_get_variable(u16 *variable_name,
				     const efi_guid_t *vendor, u32 *attributes,
				     efi_uintn_t *data_size, void *data)
{
	efi_status_t ret;

	EFI_ENTRY("\"%ls\" %pUl %p %p %p", variable_name, vendor, attributes,
		  data_size, data);

	ret = efi_get_variable_int(variable_name, vendor, attributes,
				   data_size, data, NULL);

	/* Remove EFI_VARIABLE_READ_ONLY flag */
	if (attributes)
		*attributes &= EFI_VARIABLE_MASK;

	return EFI_EXIT(ret);
}

/**
 * efi_set_variable() - set value of a UEFI variable
 *
 * This function implements the SetVariable runtime service.
 *
 * See the Unified Extensible Firmware Interface (UEFI) specification for
 * details.
 *
 * @variable_name:	name of the variable
 * @vendor:		vendor GUID
 * @attributes:		attributes of the variable
 * @data_size:		size of the buffer with the variable value
 * @data:		buffer with the variable value
 * Return:		status code
 */
efi_status_t EFIAPI efi_set_variable(u16 *variable_name,
				     const efi_guid_t *vendor, u32 attributes,
				     efi_uintn_t data_size, const void *data)
{
	efi_status_t ret;

	EFI_ENTRY("\"%ls\" %pUl %x %zu %p", variable_name, vendor, attributes,
		  data_size, data);

	/* Make sure that the EFI_VARIABLE_READ_ONLY flag is not set */
	if (attributes & ~(u32)EFI_VARIABLE_MASK)
		ret = EFI_INVALID_PARAMETER;
	else
		ret = efi_set_variable_int(variable_name, vendor, attributes,
					   data_size, data, true);

	return EFI_EXIT(ret);
}