OvmfPkg/Library/BaseMemEncryptSevLib/X64/MemEncryptSevLib.c

   1 /** @file
   2
   3   Secure Encrypted Virtualization (SEV) library helper function
   4
   5   Copyright (c) 2017 - 2020, AMD Incorporated. All rights reserved.<BR>
   6
   7   SPDX-License-Identifier: BSD-2-Clause-Patent
   8
   9 **/
  10
  11 #include <Library/BaseLib.h>
  12 #include <Library/DebugLib.h>
  13 #include <Library/MemEncryptSevLib.h>
  14 #include <Register/Amd/Cpuid.h>
  15 #include <Register/Amd/Msr.h>
  16 #include <Register/Cpuid.h>
  17
  18 #include "VirtualMemory.h"
  19
  20 /**
  21   This function clears memory encryption bit for the memory region specified by
  22   BaseAddress and NumPages from the current page table context.
  23
  24   @param[in]  Cr3BaseAddress          Cr3 Base Address (if zero then use
  25                                       current CR3)
  26   @param[in]  BaseAddress             The physical address that is the start
  27                                       address of a memory region.
  28   @param[in]  NumPages                The number of pages from start memory
  29                                       region.
  30
  31   @retval RETURN_SUCCESS              The attributes were cleared for the
  32                                       memory region.
  33   @retval RETURN_INVALID_PARAMETER    Number of pages is zero.
  34   @retval RETURN_UNSUPPORTED          Clearing the memory encryption attribute
  35                                       is not supported
  36 **/
  37 RETURN_STATUS
  38 EFIAPI
  39 MemEncryptSevClearPageEncMask (
  40   IN PHYSICAL_ADDRESS  Cr3BaseAddress,
  41   IN PHYSICAL_ADDRESS  BaseAddress,
  42   IN UINTN             NumPages
  43   )
  44 {
  45   return InternalMemEncryptSevSetMemoryDecrypted (
  46            Cr3BaseAddress,
  47            BaseAddress,
  48            EFI_PAGES_TO_SIZE (NumPages)
  49            );
  50 }
  51
  52 /**
  53   This function sets memory encryption bit for the memory region specified by
  54   BaseAddress and NumPages from the current page table context.
  55
  56   @param[in]  Cr3BaseAddress          Cr3 Base Address (if zero then use
  57                                       current CR3)
  58   @param[in]  BaseAddress             The physical address that is the start
  59                                       address of a memory region.
  60   @param[in]  NumPages                The number of pages from start memory
  61                                       region.
  62
  63   @retval RETURN_SUCCESS              The attributes were set for the memory
  64                                       region.
  65   @retval RETURN_INVALID_PARAMETER    Number of pages is zero.
  66   @retval RETURN_UNSUPPORTED          Setting the memory encryption attribute
  67                                       is not supported
  68 **/
  69 RETURN_STATUS
  70 EFIAPI
  71 MemEncryptSevSetPageEncMask (
  72   IN PHYSICAL_ADDRESS  Cr3BaseAddress,
  73   IN PHYSICAL_ADDRESS  BaseAddress,
  74   IN UINTN             NumPages
  75   )
  76 {
  77   return InternalMemEncryptSevSetMemoryEncrypted (
  78            Cr3BaseAddress,
  79            BaseAddress,
  80            EFI_PAGES_TO_SIZE (NumPages)
  81            );
  82 }
  83
  84 /**
  85   Returns the encryption state of the specified virtual address range.
  86
  87   @param[in]  Cr3BaseAddress          Cr3 Base Address (if zero then use
  88                                       current CR3)
  89   @param[in]  BaseAddress             Base address to check
  90   @param[in]  Length                  Length of virtual address range
  91
  92   @retval MemEncryptSevAddressRangeUnencrypted  Address range is mapped
  93                                                 unencrypted
  94   @retval MemEncryptSevAddressRangeEncrypted    Address range is mapped
  95                                                 encrypted
  96   @retval MemEncryptSevAddressRangeMixed        Address range is mapped mixed
  97   @retval MemEncryptSevAddressRangeError        Address range is not mapped
  98 **/
  99 MEM_ENCRYPT_SEV_ADDRESS_RANGE_STATE
 100 EFIAPI
 101 MemEncryptSevGetAddressRangeState (
 102   IN PHYSICAL_ADDRESS  Cr3BaseAddress,
 103   IN PHYSICAL_ADDRESS  BaseAddress,
 104   IN UINTN             Length
 105   )
 106 {
 107   return InternalMemEncryptSevGetAddressRangeState (
 108            Cr3BaseAddress,
 109            BaseAddress,
 110            Length
 111            );
 112 }
 113
 114 /**
 115   This function clears memory encryption bit for the mmio region specified by
 116   BaseAddress and NumPages.
 117
 118   @param[in]  Cr3BaseAddress          Cr3 Base Address (if zero then use
 119                                       current CR3)
 120   @param[in]  BaseAddress             The physical address that is the start
 121                                       address of a mmio region.
 122   @param[in]  NumPages                The number of pages from start memory
 123                                       region.
 124
 125   @retval RETURN_SUCCESS              The attributes were cleared for the
 126                                       memory region.
 127   @retval RETURN_INVALID_PARAMETER    Number of pages is zero.
 128   @retval RETURN_UNSUPPORTED          Clearing the memory encryption attribute
 129                                       is not supported
 130 **/
 131 RETURN_STATUS
 132 EFIAPI
 133 MemEncryptSevClearMmioPageEncMask (
 134   IN PHYSICAL_ADDRESS  Cr3BaseAddress,
 135   IN PHYSICAL_ADDRESS  BaseAddress,
 136   IN UINTN             NumPages
 137   )
 138 {
 139   return InternalMemEncryptSevClearMmioPageEncMask (
 140            Cr3BaseAddress,
 141            BaseAddress,
 142            EFI_PAGES_TO_SIZE (NumPages)
 143            );
 144 }