[PATCH 1/3] OvmfPkg: Realize EfiMemoryAcceptProtocol in AmdSevDxe

["Dionna Glaze" <dionnaglaze@google.com>]

From: Sophia Wolf <phiawolf@google.com>

When a guest OS does not support unaccepted memory, the unaccepted
memory must be accepted before returning a memory map to the caller.

EfiMemoryAcceptProtocol is defined in MdePkg and is implementated /
Installed in AmdSevDxe for AMD SEV-SNP memory acceptance.

Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: James Bottomley <jejb@linux.ibm.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>

Signed-off-by: Sophia Wolf <phiawolf@google.com>
---
 OvmfPkg/AmdSevDxe/AmdSevDxe.c                 | 27 ++++++++++++++
 OvmfPkg/AmdSevDxe/AmdSevDxe.inf               |  3 ++
 OvmfPkg/Include/Library/MemEncryptSevLib.h    | 14 ++++++++
 .../Ia32/MemEncryptSevLib.c                   | 17 +++++++++
 .../X64/DxeSnpSystemRamValidate.c             | 35 +++++++++++++++++++
 .../X64/PeiSnpSystemRamValidate.c             | 17 +++++++++
 .../X64/SecSnpSystemRamValidate.c             | 18 ++++++++++
 7 files changed, 131 insertions(+)

diff --git a/OvmfPkg/AmdSevDxe/AmdSevDxe.c b/OvmfPkg/AmdSevDxe/AmdSevDxe.c
index 662d3c4ccb..74b82a5814 100644
--- a/OvmfPkg/AmdSevDxe/AmdSevDxe.c
+++ b/OvmfPkg/AmdSevDxe/AmdSevDxe.c
@@ -20,6 +20,7 @@
 #include <Library/UefiBootServicesTableLib.h>
 #include <Guid/ConfidentialComputingSevSnpBlob.h>
 #include <Library/PcdLib.h>
+#include <Protocol/MemoryAccept.h>
 
 STATIC CONFIDENTIAL_COMPUTING_SNP_BLOB_LOCATION  mSnpBootDxeTable = {
   SIGNATURE_32 ('A',                                    'M', 'D', 'E'),
@@ -31,6 +32,25 @@ STATIC CONFIDENTIAL_COMPUTING_SNP_BLOB_LOCATION  mSnpBootDxeTable = {
   FixedPcdGet32 (PcdOvmfCpuidSize),
 };
 
+EFI_HANDLE mAmdSevDxeHandle = NULL;
+
+EFI_STATUS
+EFIAPI
+AmdSevMemoryAccept (
+  IN EFI_MEMORY_ACCEPT_PROTOCOL *This,
+  IN EFI_PHYSICAL_ADDRESS StartAddress,
+  IN UINTN Size
+)
+{
+  MemEncryptSnpAcceptPages (StartAddress, Size / SIZE_4KB);
+
+  return EFI_SUCCESS;
+}
+
+EFI_MEMORY_ACCEPT_PROTOCOL      mMemoryAcceptProtocol = {
+  AmdSevMemoryAccept
+};
+
 EFI_STATUS
 EFIAPI
 AmdSevDxeEntryPoint (
@@ -147,6 +167,13 @@ AmdSevDxeEntryPoint (
     }
   }
 
+  Status = gBS->InstallProtocolInterface (&mAmdSevDxeHandle,
+                  &gEfiMemoryAcceptProtocolGuid, EFI_NATIVE_INTERFACE,
+                  &mMemoryAcceptProtocol);
+  if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_ERROR, "Install EfiMemoryAcceptProtocol failed.\n"));
+  }
+
   //
   // If its SEV-SNP active guest then install the CONFIDENTIAL_COMPUTING_SEV_SNP_BLOB.
   // It contains the location for both the Secrets and CPUID page.
diff --git a/OvmfPkg/AmdSevDxe/AmdSevDxe.inf b/OvmfPkg/AmdSevDxe/AmdSevDxe.inf
index 9acf860cf2..5ddddabc32 100644
--- a/OvmfPkg/AmdSevDxe/AmdSevDxe.inf
+++ b/OvmfPkg/AmdSevDxe/AmdSevDxe.inf
@@ -47,6 +47,9 @@
   gUefiOvmfPkgTokenSpaceGuid.PcdOvmfSnpSecretsBase
   gUefiOvmfPkgTokenSpaceGuid.PcdOvmfSnpSecretsSize
 
+[Protocols]
+  gEfiMemoryAcceptProtocolGuid
+
 [Guids]
   gConfidentialComputingSevSnpBlobGuid
 
diff --git a/OvmfPkg/Include/Library/MemEncryptSevLib.h b/OvmfPkg/Include/Library/MemEncryptSevLib.h
index 4fa9c0d700..05ec10471d 100644
--- a/OvmfPkg/Include/Library/MemEncryptSevLib.h
+++ b/OvmfPkg/Include/Library/MemEncryptSevLib.h
@@ -228,4 +228,18 @@ MemEncryptSevSnpPreValidateSystemRam (
   IN UINTN             NumPages
   );
 
+/**
+  Accept pages system RAM when SEV-SNP is enabled in the guest VM.
+
+  @param[in]  BaseAddress             Base address
+  @param[in]  NumPages                Number of pages starting from the base address
+
+**/
+VOID
+EFIAPI
+MemEncryptSnpAcceptPages (
+  IN PHYSICAL_ADDRESS           BaseAddress,
+  IN UINTN                      NumPages
+  );
+
 #endif // _MEM_ENCRYPT_SEV_LIB_H_
diff --git a/OvmfPkg/Library/BaseMemEncryptSevLib/Ia32/MemEncryptSevLib.c b/OvmfPkg/Library/BaseMemEncryptSevLib/Ia32/MemEncryptSevLib.c
index f92299fc77..f0747d792e 100644
--- a/OvmfPkg/Library/BaseMemEncryptSevLib/Ia32/MemEncryptSevLib.c
+++ b/OvmfPkg/Library/BaseMemEncryptSevLib/Ia32/MemEncryptSevLib.c
@@ -153,3 +153,20 @@ MemEncryptSevSnpPreValidateSystemRam (
 {
   ASSERT (FALSE);
 }
+
+/**
+  Accept pages system RAM when SEV-SNP is enabled in the guest VM.
+
+  @param[in]  BaseAddress             Base address
+  @param[in]  NumPages                Number of pages starting from the base address
+
+**/
+VOID
+EFIAPI
+MemEncryptSnpAcceptPages (
+  IN PHYSICAL_ADDRESS           BaseAddress,
+  IN UINTN                      NumPages
+  )
+{
+  ASSERT (FALSE);
+}
diff --git a/OvmfPkg/Library/BaseMemEncryptSevLib/X64/DxeSnpSystemRamValidate.c b/OvmfPkg/Library/BaseMemEncryptSevLib/X64/DxeSnpSystemRamValidate.c
index d3a95e4913..7693e0ca66 100644
--- a/OvmfPkg/Library/BaseMemEncryptSevLib/X64/DxeSnpSystemRamValidate.c
+++ b/OvmfPkg/Library/BaseMemEncryptSevLib/X64/DxeSnpSystemRamValidate.c
@@ -14,6 +14,7 @@
 #include <Library/MemEncryptSevLib.h>
 
 #include "SnpPageStateChange.h"
+#include "VirtualMemory.h"
 
 /**
   Pre-validate the system RAM when SEV-SNP is enabled in the guest VM.
@@ -38,3 +39,37 @@ MemEncryptSevSnpPreValidateSystemRam (
   //
   ASSERT (FALSE);
 }
+
+/**
+  Accept pages system RAM when SEV-SNP is enabled in the guest VM.
+
+  @param[in]  BaseAddress             Base address
+  @param[in]  NumPages                Number of pages starting from the base address
+
+**/
+VOID
+EFIAPI
+MemEncryptSnpAcceptPages (
+  IN PHYSICAL_ADDRESS           BaseAddress,
+  IN UINTN                      NumPages
+  )
+{
+  EFI_STATUS Status;
+
+  if (!MemEncryptSevSnpIsEnabled ()) {
+    return;
+  }
+  if (BaseAddress >= SIZE_4GB) {
+    Status = InternalMemEncryptSevCreateIdentityMap1G (
+               0,
+               BaseAddress,
+               EFI_PAGES_TO_SIZE (NumPages)
+               );
+    if (EFI_ERROR (Status)) {
+      ASSERT (FALSE);
+      CpuDeadLoop ();
+    }
+  }
+
+  InternalSetPageState (BaseAddress, NumPages, SevSnpPagePrivate, TRUE);
+}
diff --git a/OvmfPkg/Library/BaseMemEncryptSevLib/X64/PeiSnpSystemRamValidate.c b/OvmfPkg/Library/BaseMemEncryptSevLib/X64/PeiSnpSystemRamValidate.c
index 4970165444..1c52bfe691 100644
--- a/OvmfPkg/Library/BaseMemEncryptSevLib/X64/PeiSnpSystemRamValidate.c
+++ b/OvmfPkg/Library/BaseMemEncryptSevLib/X64/PeiSnpSystemRamValidate.c
@@ -126,3 +126,20 @@ MemEncryptSevSnpPreValidateSystemRam (
     BaseAddress = EndAddress;
   }
 }
+
+/**
+  Accept pages system RAM when SEV-SNP is enabled in the guest VM.
+
+  @param[in]  BaseAddress             Base address
+  @param[in]  NumPages                Number of pages starting from the base address
+
+**/
+VOID
+EFIAPI
+MemEncryptSnpAcceptPages (
+  IN PHYSICAL_ADDRESS           BaseAddress,
+  IN UINTN                      NumPages
+  )
+{
+  ASSERT (FALSE);
+}
diff --git a/OvmfPkg/Library/BaseMemEncryptSevLib/X64/SecSnpSystemRamValidate.c b/OvmfPkg/Library/BaseMemEncryptSevLib/X64/SecSnpSystemRamValidate.c
index 7797febb8a..edfebf6ef4 100644
--- a/OvmfPkg/Library/BaseMemEncryptSevLib/X64/SecSnpSystemRamValidate.c
+++ b/OvmfPkg/Library/BaseMemEncryptSevLib/X64/SecSnpSystemRamValidate.c
@@ -10,6 +10,7 @@
 
 #include <Uefi/UefiBaseType.h>
 #include <Library/BaseLib.h>
+#include <Library/DebugLib.h>
 #include <Library/MemEncryptSevLib.h>
 
 #include "SnpPageStateChange.h"
@@ -80,3 +81,20 @@ MemEncryptSevSnpPreValidateSystemRam (
 
   InternalSetPageState (BaseAddress, NumPages, SevSnpPagePrivate, TRUE);
 }
+
+/**
+  Accept pages system RAM when SEV-SNP is enabled in the guest VM.
+
+  @param[in]  BaseAddress             Base address
+  @param[in]  NumPages                Number of pages starting from the base address
+
+**/
+VOID
+EFIAPI
+MemEncryptSnpAcceptPages (
+  IN PHYSICAL_ADDRESS           BaseAddress,
+  IN UINTN                      NumPages
+  )
+{
+  ASSERT(FALSE);
+}
-- 
2.37.3.998.g577e59143f-goog