From 0e182f2305a84fdf62ff2631de6e363a5a881287 Mon Sep 17 00:00:00 2001

From: Laszlo Ersek <lersek@redhat.com>

Date: Wed, 5 Jun 2013 10:14:34 +0200

Subject: [PATCH 1/3] OvmfPkg/SmbiosPlatformDxe: install legacy QEMU tables and

 save fields (X86)

Introduce basic legacy SMBIOS machinery for the QEMU platform:

- Install SMBIOS tables that QEMU passes down in complete form via fw_cfg.

- Stash individual fields that QEMU passes down to override the boot

  firmware's default SMBIOS tables.

- Add helper functions that OVMF's default SMBIOS tables will need.

Contributed-under: TianoCore Contribution Agreement 1.0

Signed-off-by: Laszlo Ersek <lersek@redhat.com>

---

 OvmfPkg/SmbiosPlatformDxe/QemuLegacy.c          | 694 ++++++++++++++++++++++++

 OvmfPkg/SmbiosPlatformDxe/QemuLegacy.h          |  52 ++

 OvmfPkg/SmbiosPlatformDxe/QemuLegacyInternal.h  | 221 ++++++++

 OvmfPkg/SmbiosPlatformDxe/SmbiosPlatformDxe.c   |  17 +-

 OvmfPkg/SmbiosPlatformDxe/SmbiosPlatformDxe.inf |   2 +

 5 files changed, 983 insertions(+), 3 deletions(-)

 create mode 100644 OvmfPkg/SmbiosPlatformDxe/QemuLegacy.c

 create mode 100644 OvmfPkg/SmbiosPlatformDxe/QemuLegacy.h

 create mode 100644 OvmfPkg/SmbiosPlatformDxe/QemuLegacyInternal.h

diff --git a/OvmfPkg/SmbiosPlatformDxe/QemuLegacy.c b/OvmfPkg/SmbiosPlatformDxe/QemuLegacy.c

new file mode 100644

index 0000000..9c57558

--- /dev/null

+++ b/OvmfPkg/SmbiosPlatformDxe/QemuLegacy.c

@@ -0,0 +1,694 @@

+/** @file

+  This file fetches and installs SMBIOS tables on the QEMU hypervisor.

+

+  Copyright (C) 2013, Red Hat, Inc.

+

+  This program and the accompanying materials are licensed and made available

+  under the terms and conditions of the BSD License which accompanies this

+  distribution.  The full text of the license may be found at

+  http://opensource.org/licenses/bsd-license.php

+

+  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, WITHOUT

+  WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

+**/

+

+#include <Library/MemoryAllocationLib.h>

+

+#include "QemuLegacy.h"

+#include "QemuLegacyInternal.h"

+

+

+//

+// An SMBIOS entry exported by QEMU over fw_cfg can have one of the following

+// types.

+//

+typedef enum

+{

+  ET_FIELD, // defines one field in some SMBIOS table

+  ET_TABLE  // defines an SMBIOS table instance in entirety

+} FW_CFG_SMBIOS_ENTRY_TYPE;

+

+//

+// Header type introducing each entry in the QemuFwCfgItemX86SmbiosTables

+// fw_cfg blob.

+//

+#pragma pack(1)

+typedef struct {

+  UINT16 Size; // including payload and this header

+  UINT8  Type; // value from FW_CFG_SMBIOS_ENTRY_TYPE

+} FW_CFG_SMBIOS_ENTRY_HDR;

+#pragma pack()

+

+//

+// Fields included at the beginning of the the payload in QEMU SMBIOS entries

+// with ET_FIELD type.

+//

+#pragma pack(1)

+typedef struct {

+  UINT8  TableType; // SMBIOS table type to patch

+  UINT16 Offset;    // offset of a field in the formatted area

+} FW_CFG_SMBIOS_FIELD;

+#pragma pack()

+

+

+/**

+  Initialize a context object tracking SMBIOS table installation and patches

+  for fields.

+

+  @param[out] Context  A BUILD_CONTEXT object allocated dynamically and

+                       initialized.

+

+  @retval EFI_OUT_OF_RESOURCES  Memory allocation failed.

+  @retval EFI_SUCCESS           Allocation and initialization successful.

+**/

+STATIC

+EFI_STATUS

+EFIAPI

+InitSmbiosContext (

+  OUT BUILD_CONTEXT **Context

+  )

+{

+  *Context = AllocateZeroPool (sizeof **Context);

+  if (*Context == NULL) {

+    DEBUG ((DEBUG_ERROR, "%a: out of memory\n", __FUNCTION__));

+    return EFI_OUT_OF_RESOURCES;

+  }

+  return EFI_SUCCESS;

+}

+

+

+/**

+  Release a context object tracking SMBIOS table installation and patches for

+  fields.

+

+  @param[in,out] Context  The BUILD_CONTEXT object to tear down.

+**/

+STATIC

+VOID

+EFIAPI

+UninitSmbiosContext (

+  IN OUT BUILD_CONTEXT *Context

+  )

+{

+  INT32 Type;

+  INT32 Idx;

+

+  //

+  // free all patches

+  //

+  for (Type = 0; Type < TABLE_TYPE_LIMIT; ++Type) {

+    for (Idx = 0; Idx < PATCH_SUBSCRIPT_LIMIT; ++Idx) {

+      PATCH *Patch;

+

+      Patch = &Context->Table[Type].Patch[Idx];

+      if (Patch->Base != NULL) {

+        FreePool (Patch->Base);

+      }

+    }

+  }

+  FreePool (Context);

+}

+

+

+/**

+  Save a patch targeting an SMBIOS field in dynamically allocated memory.

+

+  @param[in,out] Context      The initialized BUILD_CONTEXT object to save the

+                              patch in.

+  @param[in]     TableType    The patch to be saved targets this table type.

+                              Patches for table types equal to or greater than

+                              TABLE_TYPE_LIMIT are ignored.

+  @param[in]     FieldOffset  The patch to be saved targets the field that

+                              begins at offset FieldOffset in SMBIOS table type

+                              TableType. FieldOffset is enforced not to point

+                              into the SMBIOS table header. A FieldOffset value

+                              equal to or greater than 255 is rejected, since

+                              the formatted area of an SMBIOS table never

+                              exceeds 255 bytes. FieldOffset is not validated

+                              against actual field offsets here, it is only

+                              saved for later lookup.

+  @param[in]     PatchData    Byte array constituting the patch body.

+  @param[in]     PatchSize    Number of bytes in PatchData.

+

+  @retval EFI_SUCCESS            Patch has been either ignored due to not

+                                 meeting the criterion on TableType, or it has

+                                 been saved successfully.

+  @retval EFI_INVALID_PARAMETER  FieldOffset is invalid.

+  @retval EFI_OUT_OF_RESOURCES   Couldn't allocate memory for the patch.

+**/

+STATIC

+EFI_STATUS

+EFIAPI

+SaveSmbiosPatch (

+  IN OUT BUILD_CONTEXT *Context,

+  IN     UINT8         TableType,

+  IN     UINT16        FieldOffset,

+  IN     UINT8         *PatchData,

+  IN     UINT16        PatchSize

+)

+{

+  UINT8 *NewBase;

+  PATCH *Patch;

+

+  if (TableType >= TABLE_TYPE_LIMIT) {

+    DEBUG ((DEBUG_VERBOSE,

+      "%a: ignoring patch for unsupported table type %d\n",

+      __FUNCTION__, TableType));

+    return EFI_SUCCESS;

+  }

+

+  if (FieldOffset < FIELD_OFFSET_MINIMUM

+      || FieldOffset - FIELD_OFFSET_MINIMUM >= PATCH_SUBSCRIPT_LIMIT) {

+    DEBUG ((DEBUG_ERROR,

+      "%a: invalid patch for table type %d field offset %d\n",

+      __FUNCTION__, TableType, FieldOffset));

+    return EFI_INVALID_PARAMETER;

+  }

+

+  NewBase = AllocateCopyPool (PatchSize, PatchData);

+  if (PatchSize > 0 && NewBase == NULL) {

+    DEBUG ((DEBUG_ERROR, "%a: table type %d field offset %d: out of memory\n",

+      __FUNCTION__, TableType, FieldOffset));

+    return EFI_OUT_OF_RESOURCES;

+  }

+

+  Patch = &Context->Table[TableType].Patch[FieldOffset - FIELD_OFFSET_MINIMUM];

+  //

+  // replace previous patch if it exists

+  //

+  if (Patch->Base != NULL) {

+    DEBUG ((DEBUG_VERBOSE,

+      "%a: replacing prior patch for table type %d field offset %d\n",

+      __FUNCTION__, TableType, FieldOffset));

+    FreePool (Patch->Base);

+  }

+

+  Patch->Base = NewBase;

+  Patch->Size = PatchSize;

+  return EFI_SUCCESS;

+}

+

+

+/**

+  Apply a saved patch to a field located in the formatted are of a not yet

+  installed SMBIOS table.

+

+  The patch is looked up based on (Context, TableType, FieldOffset).

+

+  @param[in]  Context      The BUILD_CONTEXT object storing saved patches.

+  @param[in]  TableType    Selects the table type for which the patch has been

+                           saved. It is assumed that the caller has validated

+                           TableType against TABLE_TYPE_LIMIT (upper

+                           exclusive).

+  @param[in]  FieldOffset  Selects the SMBIOS field for which the patch has

+                           been saved. It is assumed that the caller has

+                           validated FieldOffset against FIELD_OFFSET_MINIMUM

+                           (lower inclusive) and 255 (upper exclusive).

+  @param[in]  FieldSize    The caller supplies the size of the field to patch

+                           in FieldSize. The patch saved for

+                           TableType:FieldOffset, if any, is only applied if

+                           its size equals FieldSize.

+  @param[out] TableBase    Base of the SMBIOS table of type TableType in which

+                           the field starting at FieldOffset needs to be

+                           patched.

+

+  @retval EFI_NOT_FOUND          No patch found for TableType:FieldOffset in

+                                 Context. This return value is considered

+                                 informative (ie. non-fatal).

+  @retval EFI_INVALID_PARAMETER  Patch found for TableType:FieldOffset, but its

+                                 size doesn't match FieldSize. This result is

+                                 considered a fatal error of the patch origin.

+  @retval EFI_SUCCESS            The SMBIOS table at TableBase has been patched

+                                 starting at FieldOffset for a length of

+                                 FieldSize.

+**/

+EFI_STATUS

+EFIAPI

+PatchSmbiosFormatted (

+  IN  BUILD_CONTEXT *Context,

+  IN  UINT8         TableType,

+  IN  UINT16        FieldOffset,

+  IN  UINT16        FieldSize,

+  OUT UINT8         *TableBase

+  )

+{

+  PATCH *Patch;

+

+  ASSERT (TableType < TABLE_TYPE_LIMIT);

+  ASSERT (FieldOffset >= FIELD_OFFSET_MINIMUM);

+  ASSERT (FieldOffset - FIELD_OFFSET_MINIMUM < PATCH_SUBSCRIPT_LIMIT);

+

+  Patch = &Context->Table[TableType].Patch[FieldOffset - FIELD_OFFSET_MINIMUM];

+  if (Patch->Base == NULL) {

+    return EFI_NOT_FOUND;

+  }

+

+  if (Patch->Size != FieldSize) {

+    DEBUG ((DEBUG_ERROR, "%a: table type %d, field offset %d: "

+      "patch size %d doesn't match field size %d\n",

+      __FUNCTION__, TableType, FieldOffset, Patch->Size, FieldSize));

+    return EFI_INVALID_PARAMETER;

+  }

+

+  CopyMem (TableBase + FieldOffset, Patch->Base, FieldSize);

+  return EFI_SUCCESS;

+}

+

+

+/**

+  Apply a saved patch to a text string located in the unformatted area of an

+  already installed SMBIOS table.

+

+  The patch is looked up based on (Context, TableType, FieldOffset).

+

+  @param[in]  Smbios        The EFI_SMBIOS_PROTOCOL instance used previously

+                            for installing the SMBIOS table.

+  @param[in]  SmbiosHandle  The EFI_SMBIOS_HANDLE previously returned by

+                            Smbios->Add().

+  @param[in]  Context       The BUILD_CONTEXT object storing saved patches.

+  @param[in]  TableType     Selects the table type for which the patch has been

+                            saved. It is assumed that the caller has validated

+                            TableType against TABLE_TYPE_LIMIT (upper

+                            exclusive).

+  @param[in]  FieldOffset   Selects the SMBIOS field for which the patch has

+                            been saved. It is assumed that the caller has

+                            validated FieldOffset against FIELD_OFFSET_MINIMUM

+                            (lower inclusive) and 255 (upper exclusive).

+                            It is also assumed that TableBase[FieldOffset]

+                            accesses a field of type SMBIOS_TABLE_STRING, ie. a

+                            field in the formatted area that identifies an

+                            existent text string in the unformatted area. Text

+                            string identifiers are one-based.

+  @param[out] TableBase     Base of the SMBIOS table of type TableType in which

+                            the SMBIOS_TABLE_STRING field at FieldOffset

+                            identifies the existent text string to update.

+

+  @retval EFI_NOT_FOUND          No patch found for TableType:FieldOffset in

+                                 Context. This return value is considered

+                                 informative (ie. non-fatal).

+  @retval EFI_INVALID_PARAMETER  Patch found for TableType:FieldOffset, but it

+                                 doesn't end with a NUL character. This result

+                                 is considered a fatal error of the patch

+                                 origin.

+  @retval EFI_SUCCESS            The text string identified by

+                                 TableBase[FieldOffset] has been replaced in

+                                 the installed SMBIOS table under SmbiosHandle.

+  @return                        Error codes returned by

+                                 Smbios->UpdateString(). EFI_NOT_FOUND shall

+                                 not be returned.

+**/

+EFI_STATUS

+EFIAPI

+PatchSmbiosUnformatted (

+  IN  EFI_SMBIOS_PROTOCOL *Smbios,

+  IN  EFI_SMBIOS_HANDLE   SmbiosHandle,

+  IN  BUILD_CONTEXT       *Context,

+  IN  UINT8               TableType,

+  IN  UINT16              FieldOffset,

+  IN  UINT8               *TableBase

+  )

+{

+  PATCH      *Patch;

+  UINTN      StringNumber;

+  EFI_STATUS Status;

+

+  ASSERT (TableType < TABLE_TYPE_LIMIT);

+  ASSERT (FieldOffset >= FIELD_OFFSET_MINIMUM);

+  ASSERT (FieldOffset - FIELD_OFFSET_MINIMUM < PATCH_SUBSCRIPT_LIMIT);

+

+  Patch = &Context->Table[TableType].Patch[FieldOffset - FIELD_OFFSET_MINIMUM];

+  if (Patch->Base == NULL) {

+    return EFI_NOT_FOUND;

+  }

+

+  if (Patch->Size == 0 || Patch->Base[Patch->Size - 1] != '\0') {

+    DEBUG ((DEBUG_ERROR, "%a: table type %d, field offset %d: "

+      "missing terminator, or trailing garbage\n",

+      __FUNCTION__, TableType, FieldOffset));

+    return EFI_INVALID_PARAMETER;

+  }

+

+  StringNumber = TableBase[FieldOffset];

+  ASSERT (StringNumber != 0);

+

+  Status = Smbios->UpdateString (Smbios, &SmbiosHandle, &StringNumber,

+                     (CHAR8 *)Patch->Base);

+  if (EFI_ERROR (Status)) {

+    ASSERT (Status != EFI_NOT_FOUND);

+    DEBUG ((DEBUG_ERROR, "%a: table type %d, field offset %d, "

+      "string number %d: Smbios->UpdateString(): %r\n", __FUNCTION__,

+      TableType, FieldOffset, TableBase[FieldOffset], Status));

+    return Status;

+  }

+  return EFI_SUCCESS;

+}

+

+

+/**

+  Process an SMBIOS firmware configuration entry with ET_FIELD type, exported

+  by QEMU under QemuFwCfgItemX86SmbiosTables.

+

+  Such entries describe patches to be saved with SaveSmbiosPatch().

+

+  @param[in,out] Context      The BUILD_CONTEXT object tracking saved patches.

+  @param[in]     Payload      Points to the buffer to parse as

+                              FW_CFG_SMBIOS_FIELD.

+  @param[in]     PayloadSize  Number of bytes in Payload.

+

+  @retval EFI_INVALID_PARAMETER  PayloadSize is less than the size of

+                                 FW_CFG_SMBIOS_FIELD -- fields describing

+                                 the patch are incomplete.

+  @retval EFI_SUCCESS            Payload has been parsed and patch has been

+                                 saved successfully.

+  @return                        Error codes returned by SaveSmbiosPatch().

+**/

+STATIC

+EFI_STATUS

+EFIAPI

+VisitSmbiosField (

+  IN OUT BUILD_CONTEXT *Context,

+  IN     UINT8         *Payload,

+  IN     UINT16        PayloadSize

+  )

+{

+  FW_CFG_SMBIOS_FIELD *Field;

+

+  if (PayloadSize < (INT32) sizeof *Field) {

+    DEBUG ((DEBUG_ERROR, "%a: required minimum size %d, available %d\n",

+      __FUNCTION__, (INT32) sizeof *Field, PayloadSize));

+    return EFI_INVALID_PARAMETER;

+  }

+

+  Field = (FW_CFG_SMBIOS_FIELD *) Payload;

+  return SaveSmbiosPatch (Context, Field->TableType, Field->Offset,

+           Payload + sizeof *Field, (UINT16) (PayloadSize - sizeof *Field));

+}

+

+

+/**

+  Process an SMBIOS firmware configuration entry with ET_TABLE type, exported

+  by QEMU under QemuFwCfgItemX86SmbiosTables.

+

+  Such entries describe entire SMBIOS table instances to install verbatim. This

+  module never overrides tables installed in this manner with default tables.

+

+  @param[in]     Smbios          The EFI_SMBIOS_PROTOCOL instance used for

+                                 installing SMBIOS tables.

+  @param[in]     ProducerHandle  Passed on to Smbios->Add(), ProducerHandle

+                                 tracks the origin of installed SMBIOS tables.

+  @param[in,out] Context         The BUILD_CONTEXT object tracking installed

+                                 tables.

+  @param[in]     Payload         Points to the buffer to install as an SMBIOS

+                                 table.

+  @param[in]     PayloadSize     Number of bytes in Payload.

+

+  @retval EFI_INVALID_PARAMETER  The buffer at Payload, interpreted as an

+                                 SMBIOS table, failed basic sanity checks.

+  @retval EFI_SUCCESS            Payload has been installed successfully as an

+                                 SMBIOS table.

+  @return                        Error codes returned by Smbios->Add().

+**/

+STATIC

+EFI_STATUS

+EFIAPI

+VisitSmbiosTable (

+  IN     EFI_SMBIOS_PROTOCOL *Smbios,

+  IN     EFI_HANDLE          ProducerHandle,

+  IN OUT BUILD_CONTEXT       *Context,

+  IN     UINT8               *Payload,

+  IN     UINT16              PayloadSize

+  )

+{

+  SMBIOS_STRUCTURE  *SmbiosHeader;

+  UINT16            MinimumSize;

+  EFI_SMBIOS_HANDLE SmbiosHandle;

+  EFI_STATUS        Status;

+

+  //

+  // Basic sanity checks only in order to help debugging and to catch blatantly

+  // invalid data passed with "-smbios file=binary_file" on the QEMU command

+  // line. Beyond these we don't enforce correct, type-specific SMBIOS table

+  // formatting.

+  //

+  if (PayloadSize < (INT32) sizeof *SmbiosHeader) {

+    DEBUG ((DEBUG_ERROR, "%a: required minimum size %d, available %d\n",

+      __FUNCTION__, (INT32) sizeof *SmbiosHeader, PayloadSize));

+    return EFI_INVALID_PARAMETER;

+  }

+

+  SmbiosHeader = (SMBIOS_STRUCTURE *) Payload;

+

+  if (SmbiosHeader->Length < (INT32) sizeof *SmbiosHeader) {

+    DEBUG ((DEBUG_ERROR, "%a: required minimum size %d, stated %d\n",

+      __FUNCTION__, (INT32) sizeof *SmbiosHeader, SmbiosHeader->Length));

+    return EFI_INVALID_PARAMETER;

+  }

+

+  MinimumSize = (UINT16) (SmbiosHeader->Length + 2);

+

+  if (PayloadSize < MinimumSize) {

+    DEBUG ((DEBUG_ERROR,

+      "%a: minimum for formatted area plus terminator is %d, available %d\n",

+      __FUNCTION__, MinimumSize, PayloadSize));

+    return EFI_INVALID_PARAMETER;

+  }

+

+  if (Payload[PayloadSize - 2] != '\0' ||

+      Payload[PayloadSize - 1] != '\0') {

+    DEBUG ((DEBUG_ERROR, "%a: missing terminator, or trailing garbage\n",

+      __FUNCTION__));

+    return EFI_INVALID_PARAMETER;

+  }

+

+  //

+  // request unique handle

+  //

+  SmbiosHandle = SMBIOS_HANDLE_PI_RESERVED;

+  Status = Smbios->Add (Smbios, ProducerHandle, &SmbiosHandle,

+                     (EFI_SMBIOS_TABLE_HEADER *) SmbiosHeader);

+  if (EFI_ERROR (Status)) {

+    DEBUG ((DEBUG_ERROR, "%a: Smbios->Add(): %r\n", __FUNCTION__, Status));

+    return Status;

+  }

+

+  //

+  // track known tables

+  //

+  if (SmbiosHeader->Type < TABLE_TYPE_LIMIT) {

+    Context->Table[SmbiosHeader->Type].Installed = TRUE;

+  }

+  return EFI_SUCCESS;

+}

+

+

+/**

+  Traverse the SMBIOS firmware configuration blob exported by QEMU under

+  QemuFwCfgItemX86SmbiosTables, processing each entry in turn.

+

+  Entries with ET_FIELD type are parsed as patches for the SMBIOS tables this

+  module installs as fallbacks, while entries of type ET_TABLE are parsed and

+  installed as verbatim SMBIOS tables.

+

+  Unknown entry types are silently skipped. Any error encountered during

+  traversal (for example, a recognized but malformed entry) aborts the

+  iteration, leaving the function with a possibly incomplete set of installed

+  tables.

+

+  @param[in]     Smbios          The EFI_SMBIOS_PROTOCOL instance used for

+                                 installing SMBIOS tables.

+  @param[in]     ProducerHandle  Passed on to Smbios->Add(), ProducerHandle

+                                 tracks the origin of installed SMBIOS tables.

+  @param[in,out] Context         The BUILD_CONTEXT object tracking installed

+                                 tables and saved patches.

+

+  @retval EFI_SUCCESS            The firmware configuration interface is

+                                 unavailable (no patches saved, no tables

+                                 installed).

+  @retval EFI_SUCCESS            Traversal complete. Tables provided by QEMU

+                                 have been installed. Patches have been saved

+                                 for any default tables that will be necessary.

+  @retval EFI_INVALID_PARAMETER  Encountered a corrupt entry in the SMBIOS

+                                 firmware configuration blob.

+  @retval EFI_OUT_OF_RESOURCES   Memory allocation failed.

+  @return                        Error codes returned by VisitSmbiosField() and

+                                 VisitSmbiosTable().

+**/

+STATIC

+EFI_STATUS

+EFIAPI

+ScanQemuSmbios (

+  IN     EFI_SMBIOS_PROTOCOL *Smbios,

+  IN     EFI_HANDLE          ProducerHandle,

+  IN OUT BUILD_CONTEXT       *Context

+  )

+{

+  EFI_STATUS Status;

+  UINT16     NumEntries;

+  UINT16     CurEntry;

+

+  Status = EFI_SUCCESS;

+

+  if (!QemuFwCfgIsAvailable ()) {

+    return Status;

+  }

+

+  QemuFwCfgSelectItem (QemuFwCfgItemX86SmbiosTables);

+

+  NumEntries = QemuFwCfgRead16 ();

+  for (CurEntry = 0; CurEntry < NumEntries && !EFI_ERROR (Status);

+       ++CurEntry) {

+    FW_CFG_SMBIOS_ENTRY_HDR Header;

+    UINT16                  PayloadSize;

+    UINT8                   *Payload;

+

+    QemuFwCfgReadBytes (sizeof Header, &Header);

+

+    if (Header.Size < (INT32) sizeof Header) {

+      DEBUG ((DEBUG_ERROR, "%a: invalid header size %d in entry %d\n",

+        __FUNCTION__, Header.Size, CurEntry));

+      return EFI_INVALID_PARAMETER;

+    }

+

+    PayloadSize = (UINT16) (Header.Size - sizeof Header);

+    Payload = AllocatePool (PayloadSize);

+

+    if (PayloadSize > 0 && Payload == NULL) {

+      DEBUG ((DEBUG_ERROR, "%a: failed to allocate %d bytes for entry %d\n",

+        __FUNCTION__, PayloadSize, CurEntry));

+      return EFI_OUT_OF_RESOURCES;

+    }

+

+    QemuFwCfgReadBytes (PayloadSize, Payload);

+

+    //

+    // dump the payload

+    //

+    DEBUG_CODE (

+      UINT16 Idx;

+

+      DEBUG ((DEBUG_VERBOSE,

+        "%a: entry %d, type %d, payload size %d, payload hex dump follows:",

+        __FUNCTION__, CurEntry, Header.Type, PayloadSize));

+      for (Idx = 0; Idx < PayloadSize; ++Idx) {

+        switch (Idx % 16) {

+          case 0:

+            DEBUG ((DEBUG_VERBOSE, "\n%04X:", Idx));

+            break;

+          case 8:

+            DEBUG ((DEBUG_VERBOSE, " "));

+            break;

+          default:

+            ;

+        }

+        DEBUG ((DEBUG_VERBOSE, " %02X", Payload[Idx]));

+      }

+      DEBUG ((DEBUG_VERBOSE, "\n"));

+    );

+

+    switch (Header.Type) {

+    case ET_FIELD:

+      Status = VisitSmbiosField (Context, Payload, PayloadSize);

+      break;

+    case ET_TABLE:

+      Status = VisitSmbiosTable (Smbios, ProducerHandle, Context, Payload,

+                 PayloadSize);

+      break;

+    default:

+      ;

+    }

+

+    FreePool (Payload);

+  }

+

+  return Status;

+}

+

+

+/**

+  Install some of the default SMBIOS tables for table types that QEMU hasn't

+  provided under QemuFwCfgItemX86SmbiosTables, but are required by the

+  SMBIOS-2.7.1 specification.

+

+  @param[in]     Smbios          The EFI_SMBIOS_PROTOCOL instance used for

+                                 installing SMBIOS tables.

+  @param[in]     ProducerHandle  Passed on to Smbios->Add(), ProducerHandle

+                                 tracks the origin of installed SMBIOS tables.

+  @param[in,out] Context         The BUILD_CONTEXT object tracking installed

+                                 tables and saved patches.

+

+  @return  Status codes returned by the InstallSmbiosTypeXX() functions,

+           including the final EFI_SUCCESS if all such calls succeed.

+**/

+STATIC

+EFI_STATUS

+EFIAPI

+InstallDefaultTables (

+  IN     EFI_SMBIOS_PROTOCOL *Smbios,

+  IN     EFI_HANDLE          ProducerHandle,

+  IN OUT BUILD_CONTEXT       *Context

+  )

+{

+  return EFI_SUCCESS;

+}

+

+

+/**

+  Fetch and install SMBIOS tables on the QEMU hypervisor.

+

+  First, tables provided by QEMU in entirety are installed verbatim.

+

+  Then the function prepares some of the remaining tables required by the

+  SMBIOS-2.7.1 specification. For each such table,

+  - if QEMU provides any fields for the table, they take effect verbatim,

+  - remaining fields are set by this function.

+

+  @param[in] Smbios       The EFI_SMBIOS_PROTOCOL instance used for installing

+                          the SMBIOS tables.

+  @param[in] ImageHandle  The image handle of the calling module, passed as

+                          ProducerHandle to the Smbios->Add() call.

+

+  @retval EFI_SUCCESS            All tables have been installed.

+  @retval EFI_UNSUPPORTED        The pair (Smbios->MajorVersion,

+                                 Smbios->MinorVersion) precedes (2, 3)

+                                 lexicographically.

+  @return                        Error codes returned by Smbios->Add() or

+                                 internal functions. Some tables may not have

+                                 been installed or fully patched.

+**/

+EFI_STATUS

+EFIAPI

+InstallQemuSmbiosTables (

+  IN EFI_SMBIOS_PROTOCOL *Smbios,

+  IN EFI_HANDLE          ImageHandle

+  )

+{

+  EFI_STATUS    Status;

+  BUILD_CONTEXT *Context;

+

+  if (Smbios->MajorVersion < 2 || Smbios->MinorVersion < 3) {

+    DEBUG ((DEBUG_ERROR, "%a: unsupported Smbios version %d.%d\n",

+      __FUNCTION__, Smbios->MajorVersion, Smbios->MinorVersion));

+    return EFI_UNSUPPORTED;

+  }

+

+  Status = InitSmbiosContext (&Context);

+  if (EFI_ERROR (Status)) {

+    return Status;

+  }

+

+  //

+  // <IndustryStandard/SmBios.h> and <Protocol/Smbios.h> must agree.

+  //

+  ASSERT (sizeof(SMBIOS_STRUCTURE) == sizeof(EFI_SMBIOS_TABLE_HEADER));

+

+  Status = ScanQemuSmbios (Smbios, ImageHandle, Context);

+  if (EFI_ERROR (Status)) {

+    goto Cleanup;

+  }

+

+  Status = InstallDefaultTables (Smbios, ImageHandle, Context);

+

+Cleanup:

+  UninitSmbiosContext (Context);

+  return Status;

+}

diff --git a/OvmfPkg/SmbiosPlatformDxe/QemuLegacy.h b/OvmfPkg/SmbiosPlatformDxe/QemuLegacy.h

new file mode 100644

index 0000000..40d5ad3

--- /dev/null

+++ b/OvmfPkg/SmbiosPlatformDxe/QemuLegacy.h

@@ -0,0 +1,52 @@

+/** @file

+  This header file provides QEMU-specific public prototypes for the main driver

+  file, "SmbiosPlatformDxe.c".

+

+  Copyright (C) 2013, Red Hat, Inc.

+

+  This program and the accompanying materials are licensed and made available

+  under the terms and conditions of the BSD License which accompanies this

+  distribution.  The full text of the license may be found at

+  http://opensource.org/licenses/bsd-license.php

+

+  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, WITHOUT

+  WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

+**/

+

+#ifndef _QEMU_LEGACY_H_

+#define _QEMU_LEGACY_H_

+

+#include <Protocol/Smbios.h>

+

+

+/**

+  Fetch and install SMBIOS tables on the QEMU hypervisor.

+

+  First, tables provided by QEMU in entirety are installed verbatim.

+

+  Then the function prepares some of the remaining tables required by the

+  SMBIOS-2.7.1 specification. For each such table,

+  - if QEMU provides any fields for the table, they take effect verbatim,

+  - remaining fields are set by this function.

+

+  @param[in] Smbios       The EFI_SMBIOS_PROTOCOL instance used for installing

+                          the SMBIOS tables.

+  @param[in] ImageHandle  The image handle of the calling module, passed as

+                          ProducerHandle to the Smbios->Add() call.

+

+  @retval EFI_SUCCESS            All tables have been installed.

+  @retval EFI_UNSUPPORTED        The pair (Smbios->MajorVersion,

+                                 Smbios->MinorVersion) precedes (2, 3)

+                                 lexicographically.

+  @return                        Error codes returned by Smbios->Add() or

+                                 internal functions. Some tables may not have

+                                 been installed or fully patched.

+**/

+EFI_STATUS

+EFIAPI

+InstallQemuSmbiosTables (

+  IN EFI_SMBIOS_PROTOCOL *Smbios,

+  IN EFI_HANDLE          ImageHandle

+  );

+

+#endif

diff --git a/OvmfPkg/SmbiosPlatformDxe/QemuLegacyInternal.h b/OvmfPkg/SmbiosPlatformDxe/QemuLegacyInternal.h

new file mode 100644

index 0000000..8613407

--- /dev/null

+++ b/OvmfPkg/SmbiosPlatformDxe/QemuLegacyInternal.h

@@ -0,0 +1,221 @@

+/** @file

+  This header provides common includes, and communicates internal types,

+  function prototypes and macros between "Qemu.c" and "QemuTypeXX.c", that

+  relate to the installation and patching of SMBIOS tables on the QEMU

+  platform.

+

+  Copyright (C) 2013, Red Hat, Inc.

+

+  This program and the accompanying materials are licensed and made available

+  under the terms and conditions of the BSD License which accompanies this

+  distribution.  The full text of the license may be found at

+  http://opensource.org/licenses/bsd-license.php

+

+  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, WITHOUT

+  WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

+**/

+

+#ifndef _QEMU_LEGACY_INTERNAL_H_

+#define _QEMU_LEGACY_INTERNAL_H_

+

+#include <IndustryStandard/SmBios.h>

+#include <Library/BaseLib.h>

+#include <Library/BaseMemoryLib.h>

+#include <Library/DebugLib.h>

+#include <Library/QemuFwCfgLib.h>

+#include <Protocol/Smbios.h>

+

+

+//

+// Type identifiers of all tables mandated by the SMBIOS-2.7.1 specification

+// fall strictly under this limit.

+//

+#define TABLE_TYPE_LIMIT (EFI_SMBIOS_TYPE_SYSTEM_BOOT_INFORMATION + 1)

+

+

+//

+// Track a patch in dynamic memory, originating from a QEMU SMBIOS firmware

+// configuration entry with ET_FIELD type.

+//

+typedef struct {

+  UINT8  *Base;

+  UINT16 Size;

+} PATCH;

+

+

+#define FIELD_OFFSET_MINIMUM  ((INT32) sizeof(SMBIOS_STRUCTURE))

+#define PATCH_SUBSCRIPT_LIMIT (255 - FIELD_OFFSET_MINIMUM)

+

+//

+// The following structure tracks the installation of each SMBIOS table with a

+// type below TABLE_TYPE_LIMIT, and captures QEMU SMBIOS firmware configuration

+// entries with ET_FIELD type that target the default table for the same type.

+//

+typedef struct {

+  BOOLEAN Installed; // at least one instance of the type has been installed

+

+  PATCH Patch[PATCH_SUBSCRIPT_LIMIT]; // Patches indexed by the field offset

+                                      // that they target in this specific

+                                      // table type. Patching the SMBIOS table

+                                      // header is not allowed, hence we can

+                                      // shift down field offsets. An unused

+                                      // element has zeroed-out fields.

+} TABLE_CONTEXT;

+

+

+//

+// Track the installation of, and stored patches for, all table types below

+// TABLE_TYPE_LIMIT.

+//

+typedef struct {

+  TABLE_CONTEXT Table[TABLE_TYPE_LIMIT];

+} BUILD_CONTEXT;

+

+

+//

+// Convenience / safety macro for defining C structure types for default SMBIOS

+// tables.

+//

+// Rules of use:

+// - Use only within #pragma pack(1).

+// - This macro depends on the macro

+//   "OVMF_TYPE ## TableType ## _STRINGS" specifying the text strings

+//   (unformatted area) for TableType. Each "QemuTypeXX.c" file needs to

+//   provide said macro before using the one below.

+//

+#define OVMF_SMBIOS(TableType)                                                \

+          typedef struct {                                                    \

+            SMBIOS_TABLE_TYPE##TableType Base;                                \

+            UINT8             Strings[sizeof OVMF_TYPE##TableType##_STRINGS]; \

+          } OVMF_TYPE##TableType

+