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OvmfPkg/MemEncryptSevLib: Make the MemEncryptSevLib available for SEC

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BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=3108

In preparation for a new interface to be added to the MemEncryptSevLib
library that will be used in SEC, create an SEC version of the library.

This requires the creation of SEC specific files.

Some of the current MemEncryptSevLib functions perform memory allocations
which cannot be performed in SEC, so these interfaces will return an error
during SEC. Also, the current MemEncryptSevLib library uses some static
variables to optimize access to variables, which cannot be used in SEC.

Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ard Biesheuvel <ard.biesheuvel@arm.com>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Acked-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Message-Id: <bc7fa76cc23784ab3f37356b6c10dfec61942c38.1610045305.git.thomas.lendacky@amd.com>
This commit is contained in:
Tom Lendacky
2021-01-07 12:48:21 -06:00
committed by mergify[bot]
parent 60b195d257
commit a746ca5b47
7 changed files with 289 additions and 4 deletions
Download Patch File Download Diff File Expand all files Collapse all files

80
OvmfPkg/Library/BaseMemEncryptSevLib/X64/SecVirtualMemory.c Normal file
View File

@@ -0,0 +1,80 @@
/** @file
Virtual Memory Management Services to set or clear the memory encryption bit
Copyright (c) 2020, AMD Incorporated. All rights reserved.<BR>
SPDX-License-Identifier: BSD-2-Clause-Patent
**/
#include <Library/CpuLib.h>
#include <Library/MemEncryptSevLib.h>
#include "VirtualMemory.h"
/**
This function clears memory encryption bit for the memory region specified by
PhysicalAddress and Length from the current page table context.
@param[in] Cr3BaseAddress Cr3 Base Address (if zero then use
current CR3)
@param[in] PhysicalAddress The physical address that is the start
address of a memory region.
@param[in] Length The length of memory region
@param[in] Flush Flush the caches before applying the
encryption mask
@retval RETURN_SUCCESS The attributes were cleared for the
memory region.
@retval RETURN_INVALID_PARAMETER Number of pages is zero.
@retval RETURN_UNSUPPORTED Clearing the memory encyrption attribute
is not supported
**/
RETURN_STATUS
EFIAPI
InternalMemEncryptSevSetMemoryDecrypted (
IN PHYSICAL_ADDRESS Cr3BaseAddress,
IN PHYSICAL_ADDRESS PhysicalAddress,
IN UINTN Length,
IN BOOLEAN Flush
)
{
//
// This function is not available during SEC.
//
return RETURN_UNSUPPORTED;
}
/**
This function sets memory encryption bit for the memory region specified by
PhysicalAddress and Length from the current page table context.
@param[in] Cr3BaseAddress Cr3 Base Address (if zero then use
current CR3)
@param[in] PhysicalAddress The physical address that is the start
address of a memory region.
@param[in] Length The length of memory region
@param[in] Flush Flush the caches before applying the
encryption mask
@retval RETURN_SUCCESS The attributes were set for the memory
region.
@retval RETURN_INVALID_PARAMETER Number of pages is zero.
@retval RETURN_UNSUPPORTED Setting the memory encyrption attribute
is not supported
**/
RETURN_STATUS
EFIAPI
InternalMemEncryptSevSetMemoryEncrypted (
IN PHYSICAL_ADDRESS Cr3BaseAddress,
IN PHYSICAL_ADDRESS PhysicalAddress,
IN UINTN Length,
IN BOOLEAN Flush
)
{
//
// This function is not available during SEC.
//
return RETURN_UNSUPPORTED;
}