-----Original Message-----
From: devel@edk2.groups.io <devel@edk2.groups.io> On Behalf Of Min Xu
Sent: Tuesday, December 13, 2022 1:48 PM
To: devel@edk2.groups.io
Cc: Tom Lendacky <thomas.lenda...@amd.com>; Aktas, Erdem
<erdemak...@google.com>; James Bottomley <j...@linux.ibm.com>; Yao,
Jiewen <jiewen....@intel.com>; Xu, Min M <min.m...@intel.com>; Gerd
Hoffmann <kra...@redhat.com>; Yao, Jiewen <jiewen....@intel.com>
Subject: [edk2-devel] [PATCH V2 3/4] OvmfPkg/IoMmuDxe: Add SEV support
for reserved shared memory
From: Tom Lendacky <thomas.lenda...@amd.com>
Add support to use the reserved shared memory within the IoMmu library.
This improves boot times for all SEV guests, with SEV-SNP benefiting the most
as it avoids the page state change call to the hypervisor.
Cc: Erdem Aktas <erdemak...@google.com>
Cc: James Bottomley <j...@linux.ibm.com>
Cc: Jiewen Yao <jiewen....@intel.com>
Cc: Min Xu <min.m...@intel.com>
Cc: Gerd Hoffmann <kra...@redhat.com>
Acked-by: Jiewen Yao <jiewen....@intel.com>
Signed-off-by: Tom Lendacky <thomas.lenda...@amd.com>
---
OvmfPkg/IoMmuDxe/CcIoMmu.c | 81 +++++++++++++++++-----------------
OvmfPkg/IoMmuDxe/IoMmuBuffer.c | 54 ++++++++++++++++++-----
2 files changed, 83 insertions(+), 52 deletions(-)
diff --git a/OvmfPkg/IoMmuDxe/CcIoMmu.c
b/OvmfPkg/IoMmuDxe/CcIoMmu.c index 1479af469881..e5cbf037c50d
100644
--- a/OvmfPkg/IoMmuDxe/CcIoMmu.c
+++ b/OvmfPkg/IoMmuDxe/CcIoMmu.c
@@ -223,30 +223,33 @@ IoMmuMap (
goto FreeMapInfo;
}
- if (CC_GUEST_IS_SEV (PcdGet64 (PcdConfidentialComputingGuestAttr))) {
- //
- // Clear the memory encryption mask on the plaintext buffer.
- //
- Status = MemEncryptSevClearPageEncMask (
- 0,
- MapInfo->PlainTextAddress,
- MapInfo->NumberOfPages
- );
- } else if (CC_GUEST_IS_TDX (PcdGet64
(PcdConfidentialComputingGuestAttr))) {
+ if (MapInfo->ReservedMemBitmap == 0) {
//
// Set the memory shared bit.
// If MapInfo->ReservedMemBitmap is 0, it means the bounce buffer is
not allocated
// from the pre-allocated shared memory, so it must be converted to
shared memory here.
//
- if (MapInfo->ReservedMemBitmap == 0) {
+ if (CC_GUEST_IS_SEV (PcdGet64 (PcdConfidentialComputingGuestAttr))) {
+ //
+ // Clear the memory encryption mask on the plaintext buffer.
+ //
+ Status = MemEncryptSevClearPageEncMask (
+ 0,
+ MapInfo->PlainTextAddress,
+ MapInfo->NumberOfPages
+ );
+ } else if (CC_GUEST_IS_TDX (PcdGet64
(PcdConfidentialComputingGuestAttr))) {
+ //
+ // Set the memory shared bit.
+ //
Status = MemEncryptTdxSetPageSharedBit (
0,
MapInfo->PlainTextAddress,
MapInfo->NumberOfPages
);
+ } else {
+ ASSERT (FALSE);
}
- } else {
- ASSERT (FALSE);
}
ASSERT_EFI_ERROR (Status);
@@ -396,30 +399,30 @@ IoMmuUnmapWorker (
break;
}
- if (CC_GUEST_IS_SEV (PcdGet64 (PcdConfidentialComputingGuestAttr))) {
- //
- // Restore the memory encryption mask on the area we used to hold the
- // plaintext.
- //
- Status = MemEncryptSevSetPageEncMask (
- 0,
- MapInfo->PlainTextAddress,
- MapInfo->NumberOfPages
- );
- } else if (CC_GUEST_IS_TDX (PcdGet64
(PcdConfidentialComputingGuestAttr))) {
- //
- // Restore the memory shared bit mask on the area we used to hold the
- // plaintext.
- //
- if (MapInfo->ReservedMemBitmap == 0) {
+ if (MapInfo->ReservedMemBitmap == 0) {
+ if (CC_GUEST_IS_SEV (PcdGet64 (PcdConfidentialComputingGuestAttr))) {
+ //
+ // Restore the memory encryption mask on the area we used to hold the
+ // plaintext.
+ //
+ Status = MemEncryptSevSetPageEncMask (
+ 0,
+ MapInfo->PlainTextAddress,
+ MapInfo->NumberOfPages
+ );
+ } else if (CC_GUEST_IS_TDX (PcdGet64
(PcdConfidentialComputingGuestAttr))) {
+ //
+ // Restore the memory shared bit mask on the area we used to hold the
+ // plaintext.
+ //
Status = MemEncryptTdxClearPageSharedBit (
0,
MapInfo->PlainTextAddress,
MapInfo->NumberOfPages
);
+ } else {
+ ASSERT (FALSE);
}
- } else {
- ASSERT (FALSE);
}
ASSERT_EFI_ERROR (Status);
@@ -924,16 +927,14 @@ InstallIoMmuProtocol (
}
//
- // Currently only Tdx guest support Reserved shared memory for DMA
operation.
+ // For CC guests, use reserved shared memory for DMA operation.
//
- if (CC_GUEST_IS_TDX (PcdGet64 (PcdConfidentialComputingGuestAttr))) {
- mReservedSharedMemSupported = TRUE;
- Status = IoMmuInitReservedSharedMem ();
- if (EFI_ERROR (Status)) {
- mReservedSharedMemSupported = FALSE;
- } else {
- DEBUG ((DEBUG_INFO, "%a: Feature of reserved memory for DMA is
supported.\n", __FUNCTION__));
- }
+ mReservedSharedMemSupported = TRUE;
+ Status = IoMmuInitReservedSharedMem ();
+ if (EFI_ERROR (Status)) {
+ mReservedSharedMemSupported = FALSE; } else {
+ DEBUG ((DEBUG_INFO, "%a: Feature of reserved memory for DMA is
+ supported.\n", __FUNCTION__));
}
return EFI_SUCCESS;
diff --git a/OvmfPkg/IoMmuDxe/IoMmuBuffer.c
b/OvmfPkg/IoMmuDxe/IoMmuBuffer.c index 1e77d8a57402..3139d10f4c2d
100644
--- a/OvmfPkg/IoMmuDxe/IoMmuBuffer.c
+++ b/OvmfPkg/IoMmuDxe/IoMmuBuffer.c
@@ -9,7 +9,9 @@
#include <Library/BaseMemoryLib.h>
#include <Library/DebugLib.h>
#include <Library/MemoryAllocationLib.h>
+#include <Library/MemEncryptSevLib.h>
#include <Library/MemEncryptTdxLib.h>
+#include <Library/PcdLib.h>
#include <Library/UefiBootServicesTableLib.h>
#include "IoMmuInternal.h"
@@ -139,6 +141,7 @@ IoMmuInitReservedSharedMem (
UINTN TotalPages;
IOMMU_RESERVED_MEM_RANGE *MemRange;
EFI_PHYSICAL_ADDRESS PhysicalAddress;
+ UINT64 SharedAddress;
if (!mReservedSharedMemSupported) {
return EFI_UNSUPPORTED;
@@ -163,12 +166,25 @@ IoMmuInitReservedSharedMem (
MemRange->StartAddressOfMemRange = PhysicalAddress;
for (Index2 = 0; Index2 < MemRange->Slots; Index2++) {
- Status = MemEncryptTdxSetPageSharedBit (
- 0,
- (UINT64)(UINTN)(MemRange->StartAddressOfMemRange + Index2
* SIZE_OF_MEM_RANGE (MemRange) + MemRange->HeaderSize),
- EFI_SIZE_TO_PAGES (MemRange->DataSize)
- );
- ASSERT (!EFI_ERROR (Status));
+ SharedAddress = (UINT64)(UINTN)(MemRange-
StartAddressOfMemRange
+ + Index2 * SIZE_OF_MEM_RANGE (MemRange) + MemRange->HeaderSize);
+
+ if (CC_GUEST_IS_SEV (PcdGet64 (PcdConfidentialComputingGuestAttr)))
{
+ Status = MemEncryptSevClearPageEncMask (
+ 0,
+ SharedAddress,
+ EFI_SIZE_TO_PAGES (MemRange->DataSize)
+ );
+ ASSERT (!EFI_ERROR (Status));
+ } else if (CC_GUEST_IS_TDX (PcdGet64
(PcdConfidentialComputingGuestAttr))) {
+ Status = MemEncryptTdxSetPageSharedBit (
+ 0,
+ SharedAddress,
+ EFI_SIZE_TO_PAGES (MemRange->DataSize)
+ );
+ ASSERT (!EFI_ERROR (Status));
+ } else {
+ ASSERT (FALSE);
+ }
}
PhysicalAddress += (MemRange->Slots * SIZE_OF_MEM_RANGE
(MemRange)); @@ -190,16 +206,30 @@
IoMmuReleaseReservedSharedMem (
EFI_STATUS Status;
UINT32 Index1, Index2;
IOMMU_RESERVED_MEM_RANGE *MemRange;
+ UINT64 SharedAddress;
for (Index1 = 0; Index1 < ARRAY_SIZE (mReservedMemRanges); Index1++) {
MemRange = &mReservedMemRanges[Index1];
for (Index2 = 0; Index2 < MemRange->Slots; Index2++) {
- Status = MemEncryptTdxClearPageSharedBit (
- 0,
- (UINT64)(UINTN)(MemRange->StartAddressOfMemRange + Index2
* SIZE_OF_MEM_RANGE (MemRange) + MemRange->HeaderSize),
- EFI_SIZE_TO_PAGES (MemRange->DataSize)
- );
- ASSERT (!EFI_ERROR (Status));
+ SharedAddress = (UINT64)(UINTN)(MemRange-
StartAddressOfMemRange
+ + Index2 * SIZE_OF_MEM_RANGE (MemRange) + MemRange->HeaderSize);
+
+ if (CC_GUEST_IS_SEV (PcdGet64 (PcdConfidentialComputingGuestAttr)))
{
+ Status = MemEncryptSevSetPageEncMask (
+ 0,
+ SharedAddress,
+ EFI_SIZE_TO_PAGES (MemRange->DataSize)
+ );
+ ASSERT (!EFI_ERROR (Status));
+ } else if (CC_GUEST_IS_TDX (PcdGet64
(PcdConfidentialComputingGuestAttr))) {
+ Status = MemEncryptTdxClearPageSharedBit (
+ 0,
+ SharedAddress,
+ EFI_SIZE_TO_PAGES (MemRange->DataSize)
+ );
+ ASSERT (!EFI_ERROR (Status));
+ } else {
+ ASSERT (FALSE);
+ }
}
}
--
2.29.2.windows.2
