OvmfPkg/Library/BaseMemEncryptSevLib/X64/SecVirtualMemory.c

   1 /** @file
   2
   3   Virtual Memory Management Services to set or clear the memory encryption bit
   4
   5   Copyright (c) 2020, AMD Incorporated. All rights reserved.<BR>
   6
   7   SPDX-License-Identifier: BSD-2-Clause-Patent
   8
   9 **/
  10
  11 #include <Library/CpuLib.h>
  12 #include <Library/MemEncryptSevLib.h>
  13
  14 #include "VirtualMemory.h"
  15
  16 /**
  17   This function clears memory encryption bit for the memory region specified by
  18   PhysicalAddress and Length from the current page table context.
  19
  20   @param[in]  Cr3BaseAddress          Cr3 Base Address (if zero then use
  21                                       current CR3)
  22   @param[in]  PhysicalAddress         The physical address that is the start
  23                                       address of a memory region.
  24   @param[in]  Length                  The length of memory region
  25   @param[in]  Flush                   Flush the caches before applying the
  26                                       encryption mask
  27
  28   @retval RETURN_SUCCESS              The attributes were cleared for the
  29                                       memory region.
  30   @retval RETURN_INVALID_PARAMETER    Number of pages is zero.
  31   @retval RETURN_UNSUPPORTED          Clearing the memory encyrption attribute
  32                                       is not supported
  33 **/
  34 RETURN_STATUS
  35 EFIAPI
  36 InternalMemEncryptSevSetMemoryDecrypted (
  37   IN  PHYSICAL_ADDRESS        Cr3BaseAddress,
  38   IN  PHYSICAL_ADDRESS        PhysicalAddress,
  39   IN  UINTN                   Length,
  40   IN  BOOLEAN                 Flush
  41   )
  42 {
  43   //
  44   // This function is not available during SEC.
  45   //
  46   return RETURN_UNSUPPORTED;
  47 }
  48
  49 /**
  50   This function sets memory encryption bit for the memory region specified by
  51   PhysicalAddress and Length from the current page table context.
  52
  53   @param[in]  Cr3BaseAddress          Cr3 Base Address (if zero then use
  54                                       current CR3)
  55   @param[in]  PhysicalAddress         The physical address that is the start
  56                                       address of a memory region.
  57   @param[in]  Length                  The length of memory region
  58   @param[in]  Flush                   Flush the caches before applying the
  59                                       encryption mask
  60
  61   @retval RETURN_SUCCESS              The attributes were set for the memory
  62                                       region.
  63   @retval RETURN_INVALID_PARAMETER    Number of pages is zero.
  64   @retval RETURN_UNSUPPORTED          Setting the memory encyrption attribute
  65                                       is not supported
  66 **/
  67 RETURN_STATUS
  68 EFIAPI
  69 InternalMemEncryptSevSetMemoryEncrypted (
  70   IN  PHYSICAL_ADDRESS        Cr3BaseAddress,
  71   IN  PHYSICAL_ADDRESS        PhysicalAddress,
  72   IN  UINTN                   Length,
  73   IN  BOOLEAN                 Flush
  74   )
  75 {
  76   //
  77   // This function is not available during SEC.
  78   //
  79   return RETURN_UNSUPPORTED;
  80 }