OvmfPkg: Apply uncrustify changes

[mirror_edk2.git] / OvmfPkg / Library / VmgExitLib / SecVmgExitVcHandler.c

/** @file\r
  X64 #VC Exception Handler functon.\r
\r
  Copyright (C) 2020, Advanced Micro Devices, Inc. All rights reserved.<BR>\r
  SPDX-License-Identifier: BSD-2-Clause-Patent\r
\r
**/\r
\r
#include <Base.h>\r
#include <Uefi.h>\r
#include <Library/BaseMemoryLib.h>\r
#include <Library/MemEncryptSevLib.h>\r
#include <Library/VmgExitLib.h>\r
#include <Register/Amd/Msr.h>\r
\r
#include "VmgExitVcHandler.h"\r
\r
/**\r
  Handle a #VC exception.\r
\r
  Performs the necessary processing to handle a #VC exception.\r
\r
  @param[in, out]  ExceptionType  Pointer to an EFI_EXCEPTION_TYPE to be set\r
                                  as value to use on error.\r
  @param[in, out]  SystemContext  Pointer to EFI_SYSTEM_CONTEXT\r
\r
  @retval  EFI_SUCCESS            Exception handled\r
  @retval  EFI_UNSUPPORTED        #VC not supported, (new) exception value to\r
                                  propagate provided\r
  @retval  EFI_PROTOCOL_ERROR     #VC handling failed, (new) exception value to\r
                                  propagate provided\r
\r
**/\r
EFI_STATUS\r
EFIAPI\r
VmgExitHandleVc (\r
  IN OUT EFI_EXCEPTION_TYPE  *ExceptionType,\r
  IN OUT EFI_SYSTEM_CONTEXT  SystemContext\r
  )\r
{\r
  MSR_SEV_ES_GHCB_REGISTER  Msr;\r
  GHCB                      *Ghcb;\r
  GHCB                      *GhcbBackup;\r
  EFI_STATUS                VcRet;\r
  BOOLEAN                   InterruptState;\r
  SEV_ES_PER_CPU_DATA       *SevEsData;\r
\r
  InterruptState = GetInterruptState ();\r
  if (InterruptState) {\r
    DisableInterrupts ();\r
  }\r
\r
  Msr.GhcbPhysicalAddress = AsmReadMsr64 (MSR_SEV_ES_GHCB);\r
  ASSERT (Msr.GhcbInfo.Function == 0);\r
  ASSERT (Msr.Ghcb != 0);\r
\r
  Ghcb       = Msr.Ghcb;\r
  GhcbBackup = NULL;\r
\r
  SevEsData = (SEV_ES_PER_CPU_DATA *)(Ghcb + 1);\r
  SevEsData->VcCount++;\r
\r
  //\r
  // Check for maximum SEC #VC nesting.\r
  //\r
  if (SevEsData->VcCount > VMGEXIT_MAXIMUM_VC_COUNT) {\r
    VmgExitIssueAssert (SevEsData);\r
  } else if (SevEsData->VcCount > 1) {\r
    UINTN  GhcbBackupSize;\r
\r
    //\r
    // Be sure that the proper amount of pages are allocated\r
    //\r
    GhcbBackupSize = (VMGEXIT_MAXIMUM_VC_COUNT - 1) * sizeof (*Ghcb);\r
    if (GhcbBackupSize > FixedPcdGet32 (PcdOvmfSecGhcbBackupSize)) {\r
      //\r
      // Not enough SEC backup pages allocated.\r
      //\r
      VmgExitIssueAssert (SevEsData);\r
    }\r
\r
    //\r
    // Save the active GHCB to a backup page.\r
    //   To access the correct backup page, increment the backup page pointer\r
    //   based on the current VcCount.\r
    //\r
    GhcbBackup  = (GHCB *)FixedPcdGet32 (PcdOvmfSecGhcbBackupBase);\r
    GhcbBackup += (SevEsData->VcCount - 2);\r
\r
    CopyMem (GhcbBackup, Ghcb, sizeof (*Ghcb));\r
  }\r
\r
  VcRet = InternalVmgExitHandleVc (Ghcb, ExceptionType, SystemContext);\r
\r
  if (GhcbBackup != NULL) {\r
    //\r
    // Restore the active GHCB from the backup page.\r
    //\r
    CopyMem (Ghcb, GhcbBackup, sizeof (*Ghcb));\r
  }\r
\r
  SevEsData->VcCount--;\r
\r
  if (InterruptState) {\r
    EnableInterrupts ();\r
  }\r
\r
  return VcRet;\r
}\r