OvmfPkg/Include/Library/MemEncryptSevLib.h

   1 /** @file
   2
   3   Define Secure Encrypted Virtualization (SEV) base 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 #ifndef _MEM_ENCRYPT_SEV_LIB_H_
  12 #define _MEM_ENCRYPT_SEV_LIB_H_
  13
  14 #include <Base.h>
  15
  16 //
  17 // Define the maximum number of #VCs allowed (e.g. the level of nesting
  18 // that is allowed => 2 allows for 1 nested #VCs). I this value is changed,
  19 // be sure to increase the size of
  20 //   gUefiOvmfPkgTokenSpaceGuid.PcdOvmfSecGhcbBackupSize
  21 // in any FDF file using this PCD.
  22 //
  23 #define VMGEXIT_MAXIMUM_VC_COUNT   2
  24
  25 //
  26 // Per-CPU data mapping structure
  27 //   Use UINT32 for cached indicators and compare to a specific value
  28 //   so that the hypervisor can't indicate a value is cached by just
  29 //   writing random data to that area.
  30 //
  31 typedef struct {
  32   UINT32  Dr7Cached;
  33   UINT64  Dr7;
  34
  35   UINTN   VcCount;
  36   VOID    *GhcbBackupPages;
  37 } SEV_ES_PER_CPU_DATA;
  38
  39 //
  40 // Internal structure for holding SEV-ES information needed during SEC phase
  41 // and valid only during SEC phase and early PEI during platform
  42 // initialization.
  43 //
  44 // This structure is also used by assembler files:
  45 //   OvmfPkg/ResetVector/ResetVector.nasmb
  46 //   OvmfPkg/ResetVector/Ia32/PageTables64.asm
  47 //   OvmfPkg/ResetVector/Ia32/Flat32ToFlat64.asm
  48 // any changes must stay in sync with its usage.
  49 //
  50 typedef struct _SEC_SEV_ES_WORK_AREA {
  51   UINT8    SevEsEnabled;
  52   UINT8    Reserved1[7];
  53
  54   UINT64   RandomData;
  55
  56   UINT64   EncryptionMask;
  57 } SEC_SEV_ES_WORK_AREA;
  58
  59 //
  60 // Memory encryption address range states.
  61 //
  62 typedef enum {
  63   MemEncryptSevAddressRangeUnencrypted,
  64   MemEncryptSevAddressRangeEncrypted,
  65   MemEncryptSevAddressRangeMixed,
  66   MemEncryptSevAddressRangeError,
  67 } MEM_ENCRYPT_SEV_ADDRESS_RANGE_STATE;
  68
  69 /**
  70   Returns a boolean to indicate whether SEV-ES is enabled.
  71
  72   @retval TRUE           SEV-ES is enabled
  73   @retval FALSE          SEV-ES is not enabled
  74 **/
  75 BOOLEAN
  76 EFIAPI
  77 MemEncryptSevEsIsEnabled (
  78   VOID
  79   );
  80
  81 /**
  82   Returns a boolean to indicate whether SEV is enabled
  83
  84   @retval TRUE           SEV is enabled
  85   @retval FALSE          SEV is not enabled
  86 **/
  87 BOOLEAN
  88 EFIAPI
  89 MemEncryptSevIsEnabled (
  90   VOID
  91   );
  92
  93 /**
  94   This function clears memory encryption bit for the memory region specified by
  95   BaseAddress and NumPages from the current page table context.
  96
  97   @param[in]  Cr3BaseAddress          Cr3 Base Address (if zero then use
  98                                       current CR3)
  99   @param[in]  BaseAddress             The physical address that is the start
 100                                       address of a memory region.
 101   @param[in]  NumPages                The number of pages from start memory
 102                                       region.
 103
 104   @retval RETURN_SUCCESS              The attributes were cleared for the
 105                                       memory region.
 106   @retval RETURN_INVALID_PARAMETER    Number of pages is zero.
 107   @retval RETURN_UNSUPPORTED          Clearing the memory encryption attribute
 108                                       is not supported
 109 **/
 110 RETURN_STATUS
 111 EFIAPI
 112 MemEncryptSevClearPageEncMask (
 113   IN PHYSICAL_ADDRESS         Cr3BaseAddress,
 114   IN PHYSICAL_ADDRESS         BaseAddress,
 115   IN UINTN                    NumPages
 116   );
 117
 118 /**
 119   This function sets memory encryption bit for the memory region specified by
 120   BaseAddress and NumPages from the current page table context.
 121
 122   @param[in]  Cr3BaseAddress          Cr3 Base Address (if zero then use
 123                                       current CR3)
 124   @param[in]  BaseAddress             The physical address that is the start
 125                                       address of a memory region.
 126   @param[in]  NumPages                The number of pages from start memory
 127                                       region.
 128
 129   @retval RETURN_SUCCESS              The attributes were set for the memory
 130                                       region.
 131   @retval RETURN_INVALID_PARAMETER    Number of pages is zero.
 132   @retval RETURN_UNSUPPORTED          Setting the memory encryption attribute
 133                                       is not supported
 134 **/
 135 RETURN_STATUS
 136 EFIAPI
 137 MemEncryptSevSetPageEncMask (
 138   IN PHYSICAL_ADDRESS         Cr3BaseAddress,
 139   IN PHYSICAL_ADDRESS         BaseAddress,
 140   IN UINTN                    NumPages
 141   );
 142
 143
 144 /**
 145   Locate the page range that covers the initial (pre-SMBASE-relocation) SMRAM
 146   Save State Map.
 147
 148   @param[out] BaseAddress     The base address of the lowest-address page that
 149                               covers the initial SMRAM Save State Map.
 150
 151   @param[out] NumberOfPages   The number of pages in the page range that covers
 152                               the initial SMRAM Save State Map.
 153
 154   @retval RETURN_SUCCESS      BaseAddress and NumberOfPages have been set on
 155                               output.
 156
 157   @retval RETURN_UNSUPPORTED  SMM is unavailable.
 158 **/
 159 RETURN_STATUS
 160 EFIAPI
 161 MemEncryptSevLocateInitialSmramSaveStateMapPages (
 162   OUT UINTN *BaseAddress,
 163   OUT UINTN *NumberOfPages
 164   );
 165
 166 /**
 167   Returns the SEV encryption mask.
 168
 169   @return  The SEV pagetable encryption mask
 170 **/
 171 UINT64
 172 EFIAPI
 173 MemEncryptSevGetEncryptionMask (
 174   VOID
 175   );
 176
 177 /**
 178   Returns the encryption state of the specified virtual address range.
 179
 180   @param[in]  Cr3BaseAddress          Cr3 Base Address (if zero then use
 181                                       current CR3)
 182   @param[in]  BaseAddress             Base address to check
 183   @param[in]  Length                  Length of virtual address range
 184
 185   @retval MemEncryptSevAddressRangeUnencrypted  Address range is mapped
 186                                                 unencrypted
 187   @retval MemEncryptSevAddressRangeEncrypted    Address range is mapped
 188                                                 encrypted
 189   @retval MemEncryptSevAddressRangeMixed        Address range is mapped mixed
 190   @retval MemEncryptSevAddressRangeError        Address range is not mapped
 191 **/
 192 MEM_ENCRYPT_SEV_ADDRESS_RANGE_STATE
 193 EFIAPI
 194 MemEncryptSevGetAddressRangeState (
 195   IN PHYSICAL_ADDRESS         Cr3BaseAddress,
 196   IN PHYSICAL_ADDRESS         BaseAddress,
 197   IN UINTN                    Length
 198   );
 199
 200 /**
 201   This function clears memory encryption bit for the MMIO region specified by
 202   BaseAddress and NumPages.
 203
 204   @param[in]  Cr3BaseAddress          Cr3 Base Address (if zero then use
 205                                       current CR3)
 206   @param[in]  BaseAddress             The physical address that is the start
 207                                       address of a MMIO region.
 208   @param[in]  NumPages                The number of pages from start memory
 209                                       region.
 210
 211   @retval RETURN_SUCCESS              The attributes were cleared for the
 212                                       memory region.
 213   @retval RETURN_INVALID_PARAMETER    Number of pages is zero.
 214   @retval RETURN_UNSUPPORTED          Clearing the memory encryption attribute
 215                                       is not supported
 216 **/
 217 RETURN_STATUS
 218 EFIAPI
 219 MemEncryptSevClearMmioPageEncMask (
 220   IN PHYSICAL_ADDRESS         Cr3BaseAddress,
 221   IN PHYSICAL_ADDRESS         BaseAddress,
 222   IN UINTN                    NumPages
 223   );
 224
 225 #endif // _MEM_ENCRYPT_SEV_LIB_H_