audk/UefiCpuPkg/Library/VmgExitLibNull/VmgExitLibNull.c

122 lines
3.2 KiB
C

/** @file
VMGEXIT Base Support Library.
Copyright (C) 2020, Advanced Micro Devices, Inc. All rights reserved.<BR>
SPDX-License-Identifier: BSD-2-Clause-Patent
**/
#include <Base.h>
#include <Uefi.h>
#include <Library/VmgExitLib.h>
/**
Perform VMGEXIT.
Sets the necessary fields of the GHCB, invokes the VMGEXIT instruction and
then handles the return actions.
The base library function returns an error in the form of a
GHCB_EVENT_INJECTION representing a GP_EXCEPTION.
@param[in, out] Ghcb A pointer to the GHCB
@param[in] ExitCode VMGEXIT code to be assigned to the SwExitCode
field of the GHCB.
@param[in] ExitInfo1 VMGEXIT information to be assigned to the
SwExitInfo1 field of the GHCB.
@param[in] ExitInfo2 VMGEXIT information to be assigned to the
SwExitInfo2 field of the GHCB.
@retval 0 VMGEXIT succeeded.
@return Exception number to be propagated, VMGEXIT
processing did not succeed.
**/
UINT64
EFIAPI
VmgExit (
IN OUT GHCB *Ghcb,
IN UINT64 ExitCode,
IN UINT64 ExitInfo1,
IN UINT64 ExitInfo2
)
{
GHCB_EVENT_INJECTION Event;
Event.Uint64 = 0;
Event.Elements.Vector = GP_EXCEPTION;
Event.Elements.Type = GHCB_EVENT_INJECTION_TYPE_EXCEPTION;
Event.Elements.Valid = 1;
return Event.Uint64;
}
/**
Perform pre-VMGEXIT initialization/preparation.
Performs the necessary steps in preparation for invoking VMGEXIT. Must be
called before setting any fields within the GHCB.
The base library function does nothing.
@param[in, out] Ghcb A pointer to the GHCB
**/
VOID
EFIAPI
VmgInit (
IN OUT GHCB *Ghcb
)
{
}
/**
Perform post-VMGEXIT cleanup.
Performs the necessary steps to cleanup after invoking VMGEXIT. Must be
called after obtaining needed fields within the GHCB.
The base library function does nothing.
@param[in, out] Ghcb A pointer to the GHCB
**/
VOID
EFIAPI
VmgDone (
IN OUT GHCB *Ghcb
)
{
}
/**
Handle a #VC exception.
Performs the necessary processing to handle a #VC exception.
The base library function returns an error equal to VC_EXCEPTION,
to be propagated to the standard exception handling stack.
@param[in, out] ExceptionType Pointer to an EFI_EXCEPTION_TYPE to be set
as value to use on error.
@param[in, out] SystemContext Pointer to EFI_SYSTEM_CONTEXT
@retval EFI_SUCCESS Exception handled
@retval EFI_UNSUPPORTED #VC not supported, (new) exception value to
propagate provided
@retval EFI_PROTOCOL_ERROR #VC handling failed, (new) exception value to
propagate provided
**/
EFI_STATUS
EFIAPI
VmgExitHandleVc (
IN OUT EFI_EXCEPTION_TYPE *ExceptionType,
IN OUT EFI_SYSTEM_CONTEXT SystemContext
)
{
*ExceptionType = VC_EXCEPTION;
return EFI_UNSUPPORTED;
}