[PATCH 1/9] OvmfPkg/VmgExitLib: Update ValidBitmap settings

["Lendacky, Thomas" <thomas.lendacky@amd.com>]

From: Tom Lendacky <thomas.lendacky@amd.com>

Use OFFSET_OF () and sizeof () to calculate the GHCB register field
offsets instead of hardcoding the values in the GHCB_REGISTER enum.
Rename GHCB_REGISTER to GHCB_QWORD_OFFSET to more appropriately describe
the enum. While redefing the values, only include (and add) fields that
are used per the GHCB specification.

Also, remove the DR7 field from the GHCB_SAVE_AREA structure since it is
not used/defined in the GHCB specification and then rename the reserved
fields as appropriate.

Cc: Michael D Kinney <michael.d.kinney@intel.com>
Cc: Liming Gao <gaoliming@byosoft.com.cn>
Cc: Zhiguang Liu <zhiguang.liu@intel.com>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ard Biesheuvel <ard.biesheuvel@arm.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
---
 MdePkg/Include/Register/Amd/Ghcb.h            | 48 ++++++++------------
 OvmfPkg/Library/VmgExitLib/VmgExitVcHandler.c |  4 +-
 2 files changed, 20 insertions(+), 32 deletions(-)

diff --git a/MdePkg/Include/Register/Amd/Ghcb.h b/MdePkg/Include/Register/Amd/Ghcb.h
index 54a80da0f6d7..33c7e8939a28 100644
--- a/MdePkg/Include/Register/Amd/Ghcb.h
+++ b/MdePkg/Include/Register/Amd/Ghcb.h
@@ -82,50 +82,25 @@
 #define IOIO_SEG_DS         (BIT11 | BIT10)
 
 
-typedef enum {
-  GhcbCpl              = 25,
-  GhcbRflags           = 46,
-  GhcbRip,
-  GhcbRsp              = 59,
-  GhcbRax              = 63,
-  GhcbRcx              = 97,
-  GhcbRdx,
-  GhcbRbx,
-  GhcbRbp              = 101,
-  GhcbRsi,
-  GhcbRdi,
-  GhcbR8,
-  GhcbR9,
-  GhcbR10,
-  GhcbR11,
-  GhcbR12,
-  GhcbR13,
-  GhcbR14,
-  GhcbR15,
-  GhcbXCr0             = 125,
-} GHCB_REGISTER;
-
 typedef PACKED struct {
   UINT8                  Reserved1[203];
   UINT8                  Cpl;
-  UINT8                  Reserved2[148];
-  UINT64                 Dr7;
-  UINT8                  Reserved3[144];
+  UINT8                  Reserved2[300];
   UINT64                 Rax;
-  UINT8                  Reserved4[264];
+  UINT8                  Reserved3[264];
   UINT64                 Rcx;
   UINT64                 Rdx;
   UINT64                 Rbx;
-  UINT8                  Reserved5[112];
+  UINT8                  Reserved4[112];
   UINT64                 SwExitCode;
   UINT64                 SwExitInfo1;
   UINT64                 SwExitInfo2;
   UINT64                 SwScratch;
-  UINT8                  Reserved6[56];
+  UINT8                  Reserved5[56];
   UINT64                 XCr0;
   UINT8                  ValidBitmap[16];
   UINT64                 X87StateGpa;
-  UINT8                  Reserved7[1016];
+  UINT8                  Reserved6[1016];
 } GHCB_SAVE_AREA;
 
 typedef PACKED struct {
@@ -136,6 +111,19 @@ typedef PACKED struct {
   UINT32                 GhcbUsage;
 } GHCB;
 
+typedef enum {
+  GhcbCpl          = OFFSET_OF (GHCB, SaveArea.Cpl) / sizeof (UINT64),
+  GhcbRax          = OFFSET_OF (GHCB, SaveArea.Rax) / sizeof (UINT64),
+  GhcbRbx          = OFFSET_OF (GHCB, SaveArea.Rbx) / sizeof (UINT64),
+  GhcbRcx          = OFFSET_OF (GHCB, SaveArea.Rcx) / sizeof (UINT64),
+  GhcbRdx          = OFFSET_OF (GHCB, SaveArea.Rdx) / sizeof (UINT64),
+  GhcbXCr0         = OFFSET_OF (GHCB, SaveArea.XCr0) / sizeof (UINT64),
+  GhcbSwExitCode   = OFFSET_OF (GHCB, SaveArea.SwExitCode) / sizeof (UINT64),
+  GhcbSwExitInfo1  = OFFSET_OF (GHCB, SaveArea.SwExitInfo1) / sizeof (UINT64),
+  GhcbSwExitInfo2  = OFFSET_OF (GHCB, SaveArea.SwExitInfo2) / sizeof (UINT64),
+  GhcbSwScratch    = OFFSET_OF (GHCB, SaveArea.SwScratch) / sizeof (UINT64),
+} GHCB_QWORD_OFFSET;
+
 typedef union {
   struct {
     UINT32  Lower32Bits;
diff --git a/OvmfPkg/Library/VmgExitLib/VmgExitVcHandler.c b/OvmfPkg/Library/VmgExitLib/VmgExitVcHandler.c
index 8e42b305e83c..c5484a3f478c 100644
--- a/OvmfPkg/Library/VmgExitLib/VmgExitVcHandler.c
+++ b/OvmfPkg/Library/VmgExitLib/VmgExitVcHandler.c
@@ -153,7 +153,7 @@ STATIC
 BOOLEAN
 GhcbIsRegValid (
   IN GHCB                *Ghcb,
-  IN GHCB_REGISTER       Reg
+  IN GHCB_QWORD_OFFSET   Reg
   )
 {
   UINT32  RegIndex;
@@ -179,7 +179,7 @@ STATIC
 VOID
 GhcbSetRegValid (
   IN OUT GHCB                *Ghcb,
-  IN     GHCB_REGISTER       Reg
+  IN     GHCB_QWORD_OFFSET   Reg
   )
 {
   UINT32  RegIndex;
-- 
2.28.0