audk/OvmfPkg/Library/BaseMemEncryptSevLib/X64/MemEncryptSevLib.c

85 lines
3.4 KiB
C

/** @file
Secure Encrypted Virtualization (SEV) library helper function
Copyright (c) 2017, AMD Incorporated. All rights reserved.<BR>
This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD
License which accompanies this distribution. The full text of the license may
be found at http://opensource.org/licenses/bsd-license.php
THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
**/
#include <Library/BaseLib.h>
#include <Library/DebugLib.h>
#include <Register/Cpuid.h>
#include <Register/Amd/Cpuid.h>
#include <Register/Amd/Msr.h>
#include <Library/MemEncryptSevLib.h>
#include "VirtualMemory.h"
/**
This function clears memory encryption bit for the memory region specified by
BaseAddress and Number of pages from the current page table context.
@param[in] Cr3BaseAddress Cr3 Base Address (if zero then use current CR3)
@param[in] BaseAddress The physical address that is the start address
of a memory region.
@param[in] NumberOfPages The number of pages from start memory region.
@param[in] Flush Flush the caches before clearing the bit
(mostly TRUE except MMIO addresses)
@retval RETURN_SUCCESS The attributes were cleared for the memory
region.
@retval RETURN_INVALID_PARAMETER Number of pages is zero.
@retval RETURN_UNSUPPORTED Clearing the memory encryption attribute is
not supported
**/
RETURN_STATUS
EFIAPI
MemEncryptSevClearPageEncMask (
IN PHYSICAL_ADDRESS Cr3BaseAddress,
IN PHYSICAL_ADDRESS BaseAddress,
IN UINTN NumPages,
IN BOOLEAN Flush
)
{
return InternalMemEncryptSevSetMemoryDecrypted (Cr3BaseAddress, BaseAddress, EFI_PAGES_TO_SIZE(NumPages), Flush);
}
/**
This function clears memory encryption bit for the memory region specified by
BaseAddress and Number of pages from the current page table context.
@param[in] Cr3BaseAddress Cr3 Base Address (if zero then use current CR3)
@param[in] BaseAddress The physical address that is the start address
of a memory region.
@param[in] NumberOfPages The number of pages from start memory region.
@param[in] Flush Flush the caches before clearing the bit
(mostly TRUE except MMIO addresses)
@retval RETURN_SUCCESS The attributes were cleared for the memory
region.
@retval RETURN_INVALID_PARAMETER Number of pages is zero.
@retval RETURN_UNSUPPORTED Clearing the memory encryption attribute is
not supported
**/
RETURN_STATUS
EFIAPI
MemEncryptSevSetPageEncMask (
IN PHYSICAL_ADDRESS Cr3BaseAddress,
IN PHYSICAL_ADDRESS BaseAddress,
IN UINTN NumPages,
IN BOOLEAN Flush
)
{
return InternalMemEncryptSevSetMemoryEncrypted (Cr3BaseAddress, BaseAddress, EFI_PAGES_TO_SIZE(NumPages), Flush);
}