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   @param[in]  Flush                   Flush the caches before applying the
  46                                       encryption mask
  47
  48   @retval RETURN_SUCCESS              The attributes were cleared for the
  49                                       memory region.
  50   @retval RETURN_INVALID_PARAMETER    Number of pages is zero.
  51   @retval RETURN_UNSUPPORTED          Clearing the memory encyrption attribute
  52                                       is not supported
  53 **/
  54 RETURN_STATUS
  55 EFIAPI
  56 InternalMemEncryptSevSetMemoryDecrypted (
  57   IN  PHYSICAL_ADDRESS        Cr3BaseAddress,
  58   IN  PHYSICAL_ADDRESS        PhysicalAddress,
  59   IN  UINTN                   Length,
  60   IN  BOOLEAN                 Flush
  61   )
  62 {
  63   //
  64   // This function is not available during SEC.
  65   //
  66   return RETURN_UNSUPPORTED;
  67 }
  68
  69 /**
  70   This function sets memory encryption bit for the memory region specified by
  71   PhysicalAddress and Length from the current page table context.
  72
  73   @param[in]  Cr3BaseAddress          Cr3 Base Address (if zero then use
  74                                       current CR3)
  75   @param[in]  PhysicalAddress         The physical address that is the start
  76                                       address of a memory region.
  77   @param[in]  Length                  The length of memory region
  78   @param[in]  Flush                   Flush the caches before applying the
  79                                       encryption mask
  80
  81   @retval RETURN_SUCCESS              The attributes were set for the memory
  82                                       region.
  83   @retval RETURN_INVALID_PARAMETER    Number of pages is zero.
  84   @retval RETURN_UNSUPPORTED          Setting the memory encyrption attribute
  85                                       is not supported
  86 **/
  87 RETURN_STATUS
  88 EFIAPI
  89 InternalMemEncryptSevSetMemoryEncrypted (
  90   IN  PHYSICAL_ADDRESS        Cr3BaseAddress,
  91   IN  PHYSICAL_ADDRESS        PhysicalAddress,
  92   IN  UINTN                   Length,
  93   IN  BOOLEAN                 Flush
  94   )
  95 {
  96   //
  97   // This function is not available during SEC.
  98   //
  99   return RETURN_UNSUPPORTED;
 100 }
 101
 102 /**
 103   This function clears memory encryption bit for the MMIO region specified by
 104   PhysicalAddress and Length.
 105
 106   @param[in]  Cr3BaseAddress          Cr3 Base Address (if zero then use
 107                                       current CR3)
 108   @param[in]  PhysicalAddress         The physical address that is the start
 109                                       address of a MMIO region.
 110   @param[in]  Length                  The length of memory region
 111
 112   @retval RETURN_SUCCESS              The attributes were cleared for the
 113                                       memory region.
 114   @retval RETURN_INVALID_PARAMETER    Length is zero.
 115   @retval RETURN_UNSUPPORTED          Clearing the memory encyrption attribute
 116                                       is not supported
 117 **/
 118 RETURN_STATUS
 119 EFIAPI
 120 InternalMemEncryptSevClearMmioPageEncMask (
 121   IN  PHYSICAL_ADDRESS        Cr3BaseAddress,
 122   IN  PHYSICAL_ADDRESS        PhysicalAddress,
 123   IN  UINTN                   Length
 124   )
 125 {
 126   //
 127   // This function is not available during SEC.
 128   //
 129   return RETURN_UNSUPPORTED;
 130 }