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   Return the pagetable memory encryption mask.
  18
  19   @return  The pagetable memory encryption mask.
  20
  21 **/
  22 UINT64
  23 EFIAPI
  24 InternalGetMemEncryptionAddressMask (
  25   VOID
  26   )
  27 {
  28   UINT64  EncryptionMask;
  29
  30   EncryptionMask  = MemEncryptSevGetEncryptionMask ();
  31   EncryptionMask &= PAGING_1G_ADDRESS_MASK_64;
  32
  33   return EncryptionMask;
  34 }
  35
  36 /**
  37   This function clears memory encryption bit for the memory region specified by
  38   PhysicalAddress and Length from the current page table context.
  39
  40   @param[in]  Cr3BaseAddress          Cr3 Base Address (if zero then use
  41                                       current CR3)
  42   @param[in]  PhysicalAddress         The physical address that is the start
  43                                       address of a memory region.
  44   @param[in]  Length                  The length of memory region
  45
  46   @retval RETURN_SUCCESS              The attributes were cleared for the
  47                                       memory region.
  48   @retval RETURN_INVALID_PARAMETER    Number of pages is zero.
  49   @retval RETURN_UNSUPPORTED          Clearing the memory encyrption attribute
  50                                       is not supported
  51 **/
  52 RETURN_STATUS
  53 EFIAPI
  54 InternalMemEncryptSevSetMemoryDecrypted (
  55   IN  PHYSICAL_ADDRESS  Cr3BaseAddress,
  56   IN  PHYSICAL_ADDRESS  PhysicalAddress,
  57   IN  UINTN             Length
  58   )
  59 {
  60   //
  61   // This function is not available during SEC.
  62   //
  63   return RETURN_UNSUPPORTED;
  64 }
  65
  66 /**
  67   This function sets memory encryption bit for the memory region specified by
  68   PhysicalAddress and Length from the current page table context.
  69
  70   @param[in]  Cr3BaseAddress          Cr3 Base Address (if zero then use
  71                                       current CR3)
  72   @param[in]  PhysicalAddress         The physical address that is the start
  73                                       address of a memory region.
  74   @param[in]  Length                  The length of memory region
  75   @param[in]  Flush                   Flush the caches before applying the
  76                                       encryption mask
  77
  78   @retval RETURN_SUCCESS              The attributes were set for the memory
  79                                       region.
  80   @retval RETURN_INVALID_PARAMETER    Number of pages is zero.
  81   @retval RETURN_UNSUPPORTED          Setting the memory encyrption attribute
  82                                       is not supported
  83 **/
  84 RETURN_STATUS
  85 EFIAPI
  86 InternalMemEncryptSevSetMemoryEncrypted (
  87   IN  PHYSICAL_ADDRESS  Cr3BaseAddress,
  88   IN  PHYSICAL_ADDRESS  PhysicalAddress,
  89   IN  UINTN             Length
  90   )
  91 {
  92   //
  93   // This function is not available during SEC.
  94   //
  95   return RETURN_UNSUPPORTED;
  96 }
  97
  98 /**
  99   This function clears memory encryption bit for the MMIO region specified by
 100   PhysicalAddress and Length.
 101
 102   @param[in]  Cr3BaseAddress          Cr3 Base Address (if zero then use
 103                                       current CR3)
 104   @param[in]  PhysicalAddress         The physical address that is the start
 105                                       address of a MMIO region.
 106   @param[in]  Length                  The length of memory region
 107
 108   @retval RETURN_SUCCESS              The attributes were cleared for the
 109                                       memory region.
 110   @retval RETURN_INVALID_PARAMETER    Length is zero.
 111   @retval RETURN_UNSUPPORTED          Clearing the memory encyrption attribute
 112                                       is not supported
 113 **/
 114 RETURN_STATUS
 115 EFIAPI
 116 InternalMemEncryptSevClearMmioPageEncMask (
 117   IN  PHYSICAL_ADDRESS  Cr3BaseAddress,
 118   IN  PHYSICAL_ADDRESS  PhysicalAddress,
 119   IN  UINTN             Length
 120   )
 121 {
 122   //
 123   // This function is not available during SEC.
 124   //
 125   return RETURN_UNSUPPORTED;
 126 }