VmgExitLib.c File Reference

#include <Base.h>
#include <Uefi.h>
#include <Library/BaseMemoryLib.h>
#include <Library/VmgExitLib.h>
#include <Register/Amd/Msr.h>

Go to the source code of this file.

Functions
STATIC UINT64	VmgExitErrorCheck (IN GHCB *Ghcb)
UINT64 EFIAPI	VmgExit (IN OUT GHCB *Ghcb, IN UINT64 ExitCode, IN UINT64 ExitInfo1, IN UINT64 ExitInfo2)
VOID EFIAPI	VmgInit (IN OUT GHCB *Ghcb, IN OUT BOOLEAN *InterruptState)
VOID EFIAPI	VmgDone (IN OUT GHCB *Ghcb, IN BOOLEAN InterruptState)
VOID EFIAPI	VmgSetOffsetValid (IN OUT GHCB *Ghcb, IN GHCB_REGISTER Offset)
BOOLEAN EFIAPI	VmgIsOffsetValid (IN GHCB *Ghcb, IN GHCB_REGISTER Offset)

Detailed Description

VMGEXIT Support Library.

Copyright (C) 2020, Advanced Micro Devices, Inc. All rights reserved.
SPDX-License-Identifier: BSD-2-Clause-Patent

Definition in file VmgExitLib.c.

Function Documentation

VmgDone()

VOID EFIAPI VmgDone	(	IN OUT GHCB *	Ghcb,
		IN BOOLEAN	InterruptState
	)

Perform post-VMGEXIT cleanup.

Performs the necessary steps to cleanup after invoking VMGEXIT. Must be called after obtaining needed fields within the GHCB.

Parameters

[in,out]	Ghcb	A pointer to the GHCB
[in]	InterruptState	An indicator to conditionally (re)enable interrupts

Definition at line 175 of file VmgExitLib.c.

VmgExit()

UINT64 EFIAPI VmgExit	(	IN OUT GHCB *	Ghcb,
		IN UINT64	ExitCode,
		IN UINT64	ExitInfo1,
		IN UINT64	ExitInfo2
	)

Perform VMGEXIT.

Sets the necessary fields of the GHCB, invokes the VMGEXIT instruction and then handles the return actions.

Parameters

[in,out]	Ghcb	A pointer to the GHCB
[in]	ExitCode	VMGEXIT code to be assigned to the SwExitCode field of the GHCB.
[in]	ExitInfo1	VMGEXIT information to be assigned to the SwExitInfo1 field of the GHCB.
[in]	ExitInfo2	VMGEXIT information to be assigned to the SwExitInfo2 field of the GHCB.

Return values

0	VMGEXIT succeeded.

Returns

Exception number to be propagated, VMGEXIT processing did not succeed.

Definition at line 105 of file VmgExitLib.c.

VmgExitErrorCheck()

STATIC UINT64 VmgExitErrorCheck

(

IN GHCB *

Ghcb

)

Check for VMGEXIT error

Check if the hypervisor has returned an error after completion of the VMGEXIT by examining the SwExitInfo1 field of the GHCB.

Parameters

[in]

Ghcb

A pointer to the GHCB

Return values

0	VMGEXIT succeeded.

Returns

Exception number to be propagated, VMGEXIT processing did not succeed.

Definition at line 30 of file VmgExitLib.c.

VmgInit()

VOID EFIAPI VmgInit	(	IN OUT GHCB *	Ghcb,
		IN OUT BOOLEAN *	InterruptState
	)

Perform pre-VMGEXIT initialization/preparation.

Performs the necessary steps in preparation for invoking VMGEXIT. Must be called before setting any fields within the GHCB.

Parameters

[in,out]	Ghcb	A pointer to the GHCB
[in,out]	InterruptState	A pointer to hold the current interrupt state, used for restoring in VmgDone ()

Definition at line 145 of file VmgExitLib.c.

VmgIsOffsetValid()

BOOLEAN EFIAPI VmgIsOffsetValid	(	IN GHCB *	Ghcb,
		IN GHCB_REGISTER	Offset
	)

Checks if a specified offset is valid in the GHCB.

The ValidBitmap area represents the areas of the GHCB that have been marked valid. Return whether the bit in the ValidBitmap is set for the input offset.

Parameters

[in]	Ghcb	A pointer to the GHCB
[in]	Offset	Qword offset in the GHCB to mark valid

Return values

TRUE	Offset is marked valid in the GHCB
FALSE	Offset is not marked valid in the GHCB

Definition at line 226 of file VmgExitLib.c.

VmgSetOffsetValid()

VOID EFIAPI VmgSetOffsetValid	(	IN OUT GHCB *	Ghcb,
		IN GHCB_REGISTER	Offset
	)

Marks a field at the specified offset as valid in the GHCB.

The ValidBitmap area represents the areas of the GHCB that have been marked valid. Set the bit in ValidBitmap for the input offset.

Parameters

[in,out]	Ghcb	Pointer to the Guest-Hypervisor Communication Block
[in]	Offset	Qword offset in the GHCB to mark valid

Definition at line 197 of file VmgExitLib.c.