From ed22693f4fc4d780c19280a7a26438b7c9d84ecd Mon Sep 17 00:00:00 2001

From: Gerd Hoffmann <kraxel@redhat.com>

Date: Fri, 2 Dec 2022 14:10:09 +0100

Subject: [PATCH 31/32] OvmfPkg/QemuFwCfgLib: remove mQemuFwCfgSupported +

 mQemuFwCfgDmaSupported

Remove global variables, store the state in PlatformInfoHob instead.

Probing for fw_cfg happens on first use, at library initialization

time the Hob might not be present yet.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

Tested-by: Tom Lendacky <thomas.lendacky@amd.com>

Acked-by: Ard Biesheuvel <ardb@kernel.org>

(cherry picked from commit cda98df16228970dcf9a4ce2af5368219711b4b0)

---

 .../Library/QemuFwCfgLib/QemuFwCfgPeiLib.inf  |  4 ++

 OvmfPkg/Include/Library/PlatformInitLib.h     |  4 ++

 OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgPei.c   | 44 ++++++++++++++++---

 3 files changed, 45 insertions(+), 7 deletions(-)

diff --git a/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgPeiLib.inf b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgPeiLib.inf

index 1d7543a7d40f..b1f548febcf7 100644

--- a/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgPeiLib.inf

+++ b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgPeiLib.inf

@@ -39,8 +39,12 @@ [LibraryClasses]

   BaseLib

   BaseMemoryLib

   DebugLib

+  HobLib

   IoLib

   MemoryAllocationLib

+[Guids]

+  gUefiOvmfPkgPlatformInfoGuid

+

 [Pcd]

   gUefiOvmfPkgTokenSpaceGuid.PcdOvmfWorkAreaBase

diff --git a/OvmfPkg/Include/Library/PlatformInitLib.h b/OvmfPkg/Include/Library/PlatformInitLib.h

index da7ed76041d2..bf6f90a5761c 100644

--- a/OvmfPkg/Include/Library/PlatformInitLib.h

+++ b/OvmfPkg/Include/Library/PlatformInitLib.h

@@ -50,6 +50,10 @@ typedef struct {

   UINT32               S3AcpiReservedMemorySize;

   UINT64               FeatureControlValue;

+

+  BOOLEAN              QemuFwCfgChecked;

+  BOOLEAN              QemuFwCfgSupported;

+  BOOLEAN              QemuFwCfgDmaSupported;

 } EFI_HOB_PLATFORM_INFO;

 #pragma pack()

diff --git a/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgPei.c b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgPei.c

index a936fd103955..da86a3c84c02 100644

--- a/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgPei.c

+++ b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgPei.c

@@ -9,17 +9,17 @@

   SPDX-License-Identifier: BSD-2-Clause-Patent

 **/

+#include <PiPei.h>

 #include <Library/BaseLib.h>

-#include <Library/IoLib.h>

 #include <Library/DebugLib.h>

+#include <Library/HobLib.h>

+#include <Library/IoLib.h>

+#include <Library/PlatformInitLib.h>

 #include <Library/QemuFwCfgLib.h>

 #include <WorkArea.h>

 #include "QemuFwCfgLibInternal.h"

-STATIC BOOLEAN  mQemuFwCfgSupported = FALSE;

-STATIC BOOLEAN  mQemuFwCfgDmaSupported;

-

 /**

   Check if it is Tdx guest

@@ -93,13 +93,39 @@ QemuFwCfgProbe (

     ));

 }

+STATIC

+EFI_HOB_PLATFORM_INFO *

+QemuFwCfgGetPlatformInfo (

+  VOID

+  )

+{

+  EFI_HOB_PLATFORM_INFO  *PlatformInfoHob;

+  EFI_HOB_GUID_TYPE      *GuidHob;

+

+  GuidHob = GetFirstGuidHob (&gUefiOvmfPkgPlatformInfoGuid);

+  if (GuidHob == NULL) {

+    return NULL;

+  }

+

+  PlatformInfoHob = (EFI_HOB_PLATFORM_INFO *)GET_GUID_HOB_DATA (GuidHob);

+

+  if (!PlatformInfoHob->QemuFwCfgChecked) {

+    QemuFwCfgProbe (

+      &PlatformInfoHob->QemuFwCfgSupported,

+      &PlatformInfoHob->QemuFwCfgDmaSupported

+      );

+    PlatformInfoHob->QemuFwCfgChecked = TRUE;

+  }

+

+  return PlatformInfoHob;

+}

+

 RETURN_STATUS

 EFIAPI

 QemuFwCfgInitialize (

   VOID

   )

 {

-  QemuFwCfgProbe (&mQemuFwCfgSupported, &mQemuFwCfgDmaSupported);

   return RETURN_SUCCESS;

 }

@@ -117,7 +143,9 @@ InternalQemuFwCfgIsAvailable (

   VOID

   )

 {

-  return mQemuFwCfgSupported;

+  EFI_HOB_PLATFORM_INFO  *PlatformInfoHob = QemuFwCfgGetPlatformInfo ();

+

+  return PlatformInfoHob->QemuFwCfgSupported;

 }

 /**

@@ -132,7 +160,9 @@ InternalQemuFwCfgDmaIsAvailable (

   VOID

   )

 {

-  return mQemuFwCfgDmaSupported;

+  EFI_HOB_PLATFORM_INFO  *PlatformInfoHob = QemuFwCfgGetPlatformInfo ();

+

+  return PlatformInfoHob->QemuFwCfgDmaSupported;

 }

 /**

-- 

2.38.1