[mirror_edk2.git] / MdeModulePkg / Core / Dxe / FwVol / FwVol.c

/** @file\r
  Firmware File System driver that produce Firmware Volume protocol.\r
  Layers on top of Firmware Block protocol to produce a file abstraction\r
  of FV based files.\r
\r
Copyright (c) 2006 - 2019, Intel Corporation. All rights reserved.<BR>\r
SPDX-License-Identifier: BSD-2-Clause-Patent\r
\r
**/\r
\r
#include "DxeMain.h"\r
#include "FwVolDriver.h"\r
\r
\r
//\r
// Protocol notify related globals\r
//\r
VOID          *gEfiFwVolBlockNotifyReg;\r
EFI_EVENT     gEfiFwVolBlockEvent;\r
\r
FV_DEVICE mFvDevice = {\r
  FV2_DEVICE_SIGNATURE,\r
  NULL,\r
  NULL,\r
  {\r
    FvGetVolumeAttributes,\r
    FvSetVolumeAttributes,\r
    FvReadFile,\r
    FvReadFileSection,\r
    FvWriteFile,\r
    FvGetNextFile,\r
  sizeof (UINTN),\r
    NULL,\r
    FvGetVolumeInfo,\r
    FvSetVolumeInfo\r
  },\r
  NULL,\r
  NULL,\r
  NULL,\r
  NULL,\r
  { NULL, NULL },\r
  0,\r
  0,\r
  FALSE,\r
  FALSE\r
};\r
\r
\r
//\r
// FFS helper functions\r
//\r
/**\r
  Read data from Firmware Block by FVB protocol Read.\r
  The data may cross the multi block ranges.\r
\r
  @param  Fvb                   The FW_VOL_BLOCK_PROTOCOL instance from which to read data.\r
  @param  StartLba              Pointer to StartLba.\r
                                On input, the start logical block index from which to read.\r
                                On output,the end logical block index after reading.\r
  @param  Offset                Pointer to Offset\r
                                On input, offset into the block at which to begin reading.\r
                                On output, offset into the end block after reading.\r
  @param  DataSize              Size of data to be read.\r
  @param  Data                  Pointer to Buffer that the data will be read into.\r
\r
  @retval EFI_SUCCESS           Successfully read data from firmware block.\r
  @retval others\r
**/\r
EFI_STATUS\r
ReadFvbData (\r
  IN     EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL     *Fvb,\r
  IN OUT EFI_LBA                                *StartLba,\r
  IN OUT UINTN                                  *Offset,\r
  IN     UINTN                                  DataSize,\r
  OUT    UINT8                                  *Data\r
  )\r
{\r
  UINTN                       BlockSize;\r
  UINTN                       NumberOfBlocks;\r
  UINTN                       BlockIndex;\r
  UINTN                       ReadDataSize;\r
  EFI_STATUS                  Status;\r
\r
  //\r
  // Try read data in current block\r
  //\r
  BlockIndex   = 0;\r
  ReadDataSize = DataSize;\r
  Status = Fvb->Read (Fvb, *StartLba, *Offset, &ReadDataSize, Data);\r
  if (Status == EFI_SUCCESS) {\r
    *Offset  += DataSize;\r
    return EFI_SUCCESS;\r
  } else if (Status != EFI_BAD_BUFFER_SIZE) {\r
    //\r
    // other error will direct return\r
    //\r
    return Status;\r
  }\r
\r
  //\r
  // Data crosses the blocks, read data from next block\r
  //\r
  DataSize -= ReadDataSize;\r
  Data     += ReadDataSize;\r
  *StartLba = *StartLba + 1;\r
  while (DataSize > 0) {\r
    Status = Fvb->GetBlockSize (Fvb, *StartLba, &BlockSize, &NumberOfBlocks);\r
    if (EFI_ERROR (Status)) {\r
      return Status;\r
    }\r
\r
    //\r
    // Read data from the crossing blocks\r
    //\r
    BlockIndex = 0;\r
    while (BlockIndex < NumberOfBlocks && DataSize >= BlockSize) {\r
      Status = Fvb->Read (Fvb, *StartLba + BlockIndex, 0, &BlockSize, Data);\r
      if (EFI_ERROR (Status)) {\r
        return Status;\r
      }\r
      Data += BlockSize;\r
      DataSize -= BlockSize;\r
      BlockIndex ++;\r
    }\r
\r
    //\r
    // Data doesn't exceed the current block range.\r
    //\r
    if (DataSize < BlockSize) {\r
      break;\r
    }\r
\r
    //\r
    // Data must be got from the next block range.\r
    //\r
    *StartLba += NumberOfBlocks;\r
  }\r
\r
  //\r
  // read the remaining data\r
  //\r
  if (DataSize > 0) {\r
    Status = Fvb->Read (Fvb, *StartLba + BlockIndex, 0, &DataSize, Data);\r
    if (EFI_ERROR (Status)) {\r
      return Status;\r
    }\r
  }\r
\r
  //\r
  // Update Lba and Offset used by the following read.\r
  //\r
  *StartLba += BlockIndex;\r
  *Offset   = DataSize;\r
\r
  return EFI_SUCCESS;\r
}\r
\r
/**\r
  Given the supplied FW_VOL_BLOCK_PROTOCOL, allocate a buffer for output and\r
  copy the real length volume header into it.\r
\r
  @param  Fvb                   The FW_VOL_BLOCK_PROTOCOL instance from which to\r
                                read the volume header\r
  @param  FwVolHeader           Pointer to pointer to allocated buffer in which\r
                                the volume header is returned.\r
\r
  @retval EFI_OUT_OF_RESOURCES  No enough buffer could be allocated.\r
  @retval EFI_SUCCESS           Successfully read volume header to the allocated\r
                                buffer.\r
  @retval EFI_INVALID_PARAMETER The FV Header signature is not as expected or\r
                                the file system could not be understood.\r
\r
**/\r
EFI_STATUS\r
GetFwVolHeader (\r
  IN     EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL     *Fvb,\r
  OUT    EFI_FIRMWARE_VOLUME_HEADER             **FwVolHeader\r
  )\r
{\r
  EFI_STATUS                  Status;\r
  EFI_FIRMWARE_VOLUME_HEADER  TempFvh;\r
  UINTN                       FvhLength;\r
  EFI_LBA                     StartLba;\r
  UINTN                       Offset;\r
  UINT8                       *Buffer;\r
\r
  //\r
  // Read the standard FV header\r
  //\r
  StartLba = 0;\r
  Offset   = 0;\r
  FvhLength = sizeof (EFI_FIRMWARE_VOLUME_HEADER);\r
  Status = ReadFvbData (Fvb, &StartLba, &Offset, FvhLength, (UINT8 *)&TempFvh);\r
  if (EFI_ERROR (Status)) {\r
    return Status;\r
  }\r
\r
  //\r
  // Validate FV Header signature, if not as expected, continue.\r
  //\r
  if (TempFvh.Signature != EFI_FVH_SIGNATURE) {\r
    return EFI_INVALID_PARAMETER;\r
  }\r
\r
  //\r
  // Check to see that the file system is indeed formatted in a way we can\r
  // understand it...\r
  //\r
  if ((!CompareGuid (&TempFvh.FileSystemGuid, &gEfiFirmwareFileSystem2Guid)) &&\r
      (!CompareGuid (&TempFvh.FileSystemGuid, &gEfiFirmwareFileSystem3Guid))) {\r
    return EFI_INVALID_PARAMETER;\r
  }\r
\r
  //\r
  // Allocate a buffer for the caller\r
  //\r
  *FwVolHeader = AllocatePool (TempFvh.HeaderLength);\r
  if (*FwVolHeader == NULL) {\r
    return EFI_OUT_OF_RESOURCES;\r
  }\r
\r
  //\r
  // Copy the standard header into the buffer\r
  //\r
  CopyMem (*FwVolHeader, &TempFvh, sizeof (EFI_FIRMWARE_VOLUME_HEADER));\r
\r
  //\r
  // Read the rest of the header\r
  //\r
  FvhLength = TempFvh.HeaderLength - sizeof (EFI_FIRMWARE_VOLUME_HEADER);\r
  Buffer = (UINT8 *)*FwVolHeader + sizeof (EFI_FIRMWARE_VOLUME_HEADER);\r
  Status = ReadFvbData (Fvb, &StartLba, &Offset, FvhLength, Buffer);\r
  if (EFI_ERROR (Status)) {\r
    //\r
    // Read failed so free buffer\r
    //\r
    CoreFreePool (*FwVolHeader);\r
  }\r
\r
  return Status;\r
}\r
\r
\r
\r
/**\r
  Free FvDevice resource when error happens\r
\r
  @param  FvDevice              pointer to the FvDevice to be freed.\r
\r
**/\r
VOID\r
FreeFvDeviceResource (\r
  IN FV_DEVICE  *FvDevice\r
  )\r
{\r
  FFS_FILE_LIST_ENTRY         *FfsFileEntry;\r
  LIST_ENTRY                  *NextEntry;\r
\r
  //\r
  // Free File List Entry\r
  //\r
  FfsFileEntry = (FFS_FILE_LIST_ENTRY *)FvDevice->FfsFileListHeader.ForwardLink;\r
  while (&FfsFileEntry->Link != &FvDevice->FfsFileListHeader) {\r
    NextEntry = (&FfsFileEntry->Link)->ForwardLink;\r
\r
    if (FfsFileEntry->StreamHandle != 0) {\r
      //\r
      // Close stream and free resources from SEP\r
      //\r
      CloseSectionStream (FfsFileEntry->StreamHandle, FALSE);\r
    }\r
\r
    if (FfsFileEntry->FileCached) {\r
      //\r
      // Free the cached file buffer.\r
      //\r
      CoreFreePool (FfsFileEntry->FfsHeader);\r
    }\r
\r
    CoreFreePool (FfsFileEntry);\r
\r
    FfsFileEntry = (FFS_FILE_LIST_ENTRY *) NextEntry;\r
  }\r
\r
  if (!FvDevice->IsMemoryMapped) {\r
    //\r
    // Free the cached FV buffer.\r
    //\r
    CoreFreePool (FvDevice->CachedFv);\r
  }\r
\r
  //\r
  // Free Volume Header\r
  //\r
  CoreFreePool (FvDevice->FwVolHeader);\r
\r
  return;\r
}\r
\r
\r
\r
/**\r
  Check if an FV is consistent and allocate cache for it.\r
\r
  @param  FvDevice              A pointer to the FvDevice to be checked.\r
\r
  @retval EFI_OUT_OF_RESOURCES  No enough buffer could be allocated.\r
  @retval EFI_SUCCESS           FV is consistent and cache is allocated.\r
  @retval EFI_VOLUME_CORRUPTED  File system is corrupted.\r
\r
**/\r
EFI_STATUS\r
FvCheck (\r
  IN OUT FV_DEVICE  *FvDevice\r
  )\r
{\r
  EFI_STATUS                            Status;\r
  EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL    *Fvb;\r
  EFI_FIRMWARE_VOLUME_HEADER            *FwVolHeader;\r
  EFI_FIRMWARE_VOLUME_EXT_HEADER        *FwVolExtHeader;\r
  EFI_FVB_ATTRIBUTES_2                  FvbAttributes;\r
  EFI_FV_BLOCK_MAP_ENTRY                *BlockMap;\r
  FFS_FILE_LIST_ENTRY                   *FfsFileEntry;\r
  EFI_FFS_FILE_HEADER                   *FfsHeader;\r
  UINT8                                 *CacheLocation;\r
  UINTN                                 Index;\r
  EFI_LBA                               LbaIndex;\r
  UINTN                                 Size;\r
  EFI_FFS_FILE_STATE                    FileState;\r
  UINT8                                 *TopFvAddress;\r
  UINTN                                 TestLength;\r
  EFI_PHYSICAL_ADDRESS                  PhysicalAddress;\r
  BOOLEAN                               FileCached;\r
  UINTN                                 WholeFileSize;\r
  EFI_FFS_FILE_HEADER                   *CacheFfsHeader;\r
\r
  FileCached = FALSE;\r
  CacheFfsHeader = NULL;\r
\r
  Fvb = FvDevice->Fvb;\r
  FwVolHeader = FvDevice->FwVolHeader;\r
\r
  Status = Fvb->GetAttributes (Fvb, &FvbAttributes);\r
  if (EFI_ERROR (Status)) {\r
    return Status;\r
  }\r
\r
  Size = (UINTN) FwVolHeader->FvLength;\r
  if ((FvbAttributes & EFI_FVB2_MEMORY_MAPPED) != 0) {\r
    FvDevice->IsMemoryMapped = TRUE;\r
\r
    Status = Fvb->GetPhysicalAddress (Fvb, &PhysicalAddress);\r
    if (EFI_ERROR (Status)) {\r
      return Status;\r
    }\r
\r
    //\r
    // Don't cache memory mapped FV really.\r
    //\r
    FvDevice->CachedFv = (UINT8 *) (UINTN) PhysicalAddress;\r
  } else {\r
    FvDevice->IsMemoryMapped = FALSE;\r
    FvDevice->CachedFv = AllocatePool (Size);\r
\r
    if (FvDevice->CachedFv == NULL) {\r
      return EFI_OUT_OF_RESOURCES;\r
    }\r
  }\r
\r
  //\r
  // Remember a pointer to the end of the CachedFv\r
  //\r
  FvDevice->EndOfCachedFv = FvDevice->CachedFv + Size;\r
\r
  if (!FvDevice->IsMemoryMapped) {\r
    //\r
    // Copy FV into memory using the block map.\r
    //\r
    BlockMap = FwVolHeader->BlockMap;\r
    CacheLocation = FvDevice->CachedFv;\r
    LbaIndex = 0;\r
    while ((BlockMap->NumBlocks != 0) || (BlockMap->Length != 0)) {\r
      //\r
      // read the FV data\r
      //\r
      Size = BlockMap->Length;\r
      for (Index = 0; Index < BlockMap->NumBlocks; Index++) {\r
        Status = Fvb->Read (\r
                        Fvb,\r
                        LbaIndex,\r
                        0,\r
                        &Size,\r
                        CacheLocation\r
                        );\r
\r
        //\r
        // Not check EFI_BAD_BUFFER_SIZE, for Size = BlockMap->Length\r
        //\r
        if (EFI_ERROR (Status)) {\r
          goto Done;\r
        }\r
\r
        LbaIndex++;\r
        CacheLocation += BlockMap->Length;\r
      }\r
\r
      BlockMap++;\r
    }\r
  }\r
\r
  //\r
  // Scan to check the free space & File list\r
  //\r
  if ((FvbAttributes & EFI_FVB2_ERASE_POLARITY) != 0) {\r
    FvDevice->ErasePolarity = 1;\r
  } else {\r
    FvDevice->ErasePolarity = 0;\r
  }\r
\r
\r
  //\r
  // go through the whole FV cache, check the consistence of the FV.\r
  // Make a linked list of all the Ffs file headers\r
  //\r
  Status = EFI_SUCCESS;\r
  InitializeListHead (&FvDevice->FfsFileListHeader);\r
\r
  //\r
  // Build FFS list\r
  //\r
  if (FwVolHeader->ExtHeaderOffset != 0) {\r
    //\r
    // Searching for files starts on an 8 byte aligned boundary after the end of the Extended Header if it exists.\r
    //\r
    FwVolExtHeader = (EFI_FIRMWARE_VOLUME_EXT_HEADER *) (FvDevice->CachedFv + FwVolHeader->ExtHeaderOffset);\r
    FfsHeader = (EFI_FFS_FILE_HEADER *) ((UINT8 *) FwVolExtHeader + FwVolExtHeader->ExtHeaderSize);\r
  } else {\r
    FfsHeader = (EFI_FFS_FILE_HEADER *) (FvDevice->CachedFv + FwVolHeader->HeaderLength);\r
  }\r
  FfsHeader = (EFI_FFS_FILE_HEADER *) ALIGN_POINTER (FfsHeader, 8);\r
  TopFvAddress = FvDevice->EndOfCachedFv;\r
  while (((UINTN) FfsHeader >= (UINTN) FvDevice->CachedFv) && ((UINTN) FfsHeader <= (UINTN) ((UINTN) TopFvAddress - sizeof (EFI_FFS_FILE_HEADER)))) {\r
\r
    if (FileCached) {\r
      CoreFreePool (CacheFfsHeader);\r
      FileCached = FALSE;\r
    }\r
\r
    TestLength = TopFvAddress - ((UINT8 *) FfsHeader);\r
    if (TestLength > sizeof (EFI_FFS_FILE_HEADER)) {\r
      TestLength = sizeof (EFI_FFS_FILE_HEADER);\r
    }\r
\r
    if (IsBufferErased (FvDevice->ErasePolarity, FfsHeader, TestLength)) {\r
      //\r
      // We have found the free space so we are done!\r
      //\r
      goto Done;\r
    }\r
\r
    if (!IsValidFfsHeader (FvDevice->ErasePolarity, FfsHeader, &FileState)) {\r
      if ((FileState == EFI_FILE_HEADER_INVALID) ||\r
          (FileState == EFI_FILE_HEADER_CONSTRUCTION)) {\r
        if (IS_FFS_FILE2 (FfsHeader)) {\r
          if (!FvDevice->IsFfs3Fv) {\r
            DEBUG ((EFI_D_ERROR, "Found a FFS3 formatted file: %g in a non-FFS3 formatted FV.\n", &FfsHeader->Name));\r
          }\r
          FfsHeader = (EFI_FFS_FILE_HEADER *) ((UINT8 *) FfsHeader + sizeof (EFI_FFS_FILE_HEADER2));\r
        } else {\r
          FfsHeader = (EFI_FFS_FILE_HEADER *) ((UINT8 *) FfsHeader + sizeof (EFI_FFS_FILE_HEADER));\r
        }\r
        continue;\r
      } else {\r
        //\r
        // File system is corrputed\r
        //\r
        Status = EFI_VOLUME_CORRUPTED;\r
        goto Done;\r
      }\r
    }\r
\r
    CacheFfsHeader = FfsHeader;\r
    if ((CacheFfsHeader->Attributes & FFS_ATTRIB_CHECKSUM) == FFS_ATTRIB_CHECKSUM) {\r
      if (FvDevice->IsMemoryMapped) {\r
        //\r
        // Memory mapped FV has not been cached.\r
        // Here is to cache FFS file to memory buffer for following checksum calculating.\r
        // And then, the cached file buffer can be also used for FvReadFile.\r
        //\r
        WholeFileSize = IS_FFS_FILE2 (CacheFfsHeader) ? FFS_FILE2_SIZE (CacheFfsHeader): FFS_FILE_SIZE (CacheFfsHeader);\r
        CacheFfsHeader = AllocateCopyPool (WholeFileSize, CacheFfsHeader);\r
        if (CacheFfsHeader == NULL) {\r
          Status = EFI_OUT_OF_RESOURCES;\r
          goto Done;\r
        }\r
        FileCached = TRUE;\r
      }\r
    }\r
\r
    if (!IsValidFfsFile (FvDevice->ErasePolarity, CacheFfsHeader)) {\r
      //\r
      // File system is corrupted\r
      //\r
      Status = EFI_VOLUME_CORRUPTED;\r
      goto Done;\r
    }\r
\r
    if (IS_FFS_FILE2 (CacheFfsHeader)) {\r
      ASSERT (FFS_FILE2_SIZE (CacheFfsHeader) > 0x00FFFFFF);\r
      if (!FvDevice->IsFfs3Fv) {\r
        DEBUG ((EFI_D_ERROR, "Found a FFS3 formatted file: %g in a non-FFS3 formatted FV.\n", &CacheFfsHeader->Name));\r
        FfsHeader = (EFI_FFS_FILE_HEADER *) ((UINT8 *) FfsHeader + FFS_FILE2_SIZE (CacheFfsHeader));\r
        //\r
        // Adjust pointer to the next 8-byte aligned boundary.\r
        //\r
        FfsHeader = (EFI_FFS_FILE_HEADER *) (((UINTN) FfsHeader + 7) & ~0x07);\r
        continue;\r
      }\r
    }\r
\r
    FileState = GetFileState (FvDevice->ErasePolarity, CacheFfsHeader);\r
\r
    //\r
    // check for non-deleted file\r
    //\r
    if (FileState != EFI_FILE_DELETED) {\r
      //\r
      // Create a FFS list entry for each non-deleted file\r
      //\r
      FfsFileEntry = AllocateZeroPool (sizeof (FFS_FILE_LIST_ENTRY));\r
      if (FfsFileEntry == NULL) {\r
        Status = EFI_OUT_OF_RESOURCES;\r
        goto Done;\r
      }\r
\r
      FfsFileEntry->FfsHeader = CacheFfsHeader;\r
      FfsFileEntry->FileCached = FileCached;\r
      FileCached = FALSE;\r
      InsertTailList (&FvDevice->FfsFileListHeader, &FfsFileEntry->Link);\r
    }\r
\r
    if (IS_FFS_FILE2 (CacheFfsHeader)) {\r
      FfsHeader = (EFI_FFS_FILE_HEADER *) ((UINT8 *) FfsHeader + FFS_FILE2_SIZE (CacheFfsHeader));\r
    } else {\r
      FfsHeader = (EFI_FFS_FILE_HEADER *) ((UINT8 *) FfsHeader + FFS_FILE_SIZE (CacheFfsHeader));\r
    }\r
\r
    //\r
    // Adjust pointer to the next 8-byte aligned boundary.\r
    //\r
    FfsHeader = (EFI_FFS_FILE_HEADER *)(((UINTN)FfsHeader + 7) & ~0x07);\r
\r
  }\r
\r
Done:\r
  if (EFI_ERROR (Status)) {\r
    if (FileCached) {\r
      CoreFreePool (CacheFfsHeader);\r
      FileCached = FALSE;\r
    }\r
    FreeFvDeviceResource (FvDevice);\r
  }\r
\r
  return Status;\r
}\r
\r
\r
\r
/**\r
  This notification function is invoked when an instance of the\r
  EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL is produced.  It layers an instance of the\r
  EFI_FIRMWARE_VOLUME2_PROTOCOL on the same handle.  This is the function where\r
  the actual initialization of the EFI_FIRMWARE_VOLUME2_PROTOCOL is done.\r
\r
  @param  Event                 The event that occured\r
  @param  Context               For EFI compatiblity.  Not used.\r
\r
**/\r
VOID\r
EFIAPI\r
NotifyFwVolBlock (\r
  IN  EFI_EVENT Event,\r
  IN  VOID      *Context\r
  )\r
{\r
  EFI_HANDLE                            Handle;\r
  EFI_STATUS                            Status;\r
  UINTN                                 BufferSize;\r
  EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL    *Fvb;\r
  EFI_FIRMWARE_VOLUME2_PROTOCOL         *Fv;\r
  FV_DEVICE                             *FvDevice;\r
  EFI_FIRMWARE_VOLUME_HEADER            *FwVolHeader;\r
  //\r
  // Examine all new handles\r
  //\r
  for (;;) {\r
    //\r
    // Get the next handle\r
    //\r
    BufferSize = sizeof (Handle);\r
    Status = CoreLocateHandle (\r
              ByRegisterNotify,\r
              NULL,\r
              gEfiFwVolBlockNotifyReg,\r
              &BufferSize,\r
              &Handle\r
              );\r
\r
    //\r
    // If not found, we're done\r
    //\r
    if (EFI_NOT_FOUND == Status) {\r
      break;\r
    }\r
\r
    if (EFI_ERROR (Status)) {\r
      continue;\r
    }\r
\r
    //\r
    // Get the FirmwareVolumeBlock protocol on that handle\r
    //\r
    Status = CoreHandleProtocol (Handle, &gEfiFirmwareVolumeBlockProtocolGuid, (VOID **)&Fvb);\r
    ASSERT_EFI_ERROR (Status);\r
    ASSERT (Fvb != NULL);\r
\r
    //\r
    // Make sure the Fv Header is O.K.\r
    //\r
    Status = GetFwVolHeader (Fvb, &FwVolHeader);\r
    if (EFI_ERROR (Status)) {\r
      continue;\r
    }\r
    ASSERT (FwVolHeader != NULL);\r
\r
    if (!VerifyFvHeaderChecksum (FwVolHeader)) {\r
      CoreFreePool (FwVolHeader);\r
      continue;\r
    }\r
\r
    //\r
    // Check if there is an FV protocol already installed in that handle\r
    //\r
    Status = CoreHandleProtocol (Handle, &gEfiFirmwareVolume2ProtocolGuid, (VOID **)&Fv);\r
    if (!EFI_ERROR (Status)) {\r
      //\r
      // Update Fv to use a new Fvb\r
      //\r
      FvDevice = BASE_CR (Fv, FV_DEVICE, Fv);\r
      if (FvDevice->Signature == FV2_DEVICE_SIGNATURE) {\r
        //\r
        // Only write into our device structure if it's our device structure\r
        //\r
        FvDevice->Fvb = Fvb;\r
      }\r
\r
    } else {\r
      //\r
      // No FwVol protocol on the handle so create a new one\r
      //\r
      FvDevice = AllocateCopyPool (sizeof (FV_DEVICE), &mFvDevice);\r
      if (FvDevice == NULL) {\r
        return;\r
      }\r
\r
      FvDevice->Fvb             = Fvb;\r
      FvDevice->Handle          = Handle;\r
      FvDevice->FwVolHeader     = FwVolHeader;\r
      FvDevice->IsFfs3Fv        = CompareGuid (&FwVolHeader->FileSystemGuid, &gEfiFirmwareFileSystem3Guid);\r
      FvDevice->Fv.ParentHandle = Fvb->ParentHandle;\r
      //\r
      // Inherit the authentication status from FVB.\r
      //\r
      FvDevice->AuthenticationStatus = GetFvbAuthenticationStatus (Fvb);\r
\r
      if (!EFI_ERROR (FvCheck (FvDevice))) {\r
        //\r
        // Install an New FV protocol on the existing handle\r
        //\r
        Status = CoreInstallProtocolInterface (\r
                    &Handle,\r
                    &gEfiFirmwareVolume2ProtocolGuid,\r
                    EFI_NATIVE_INTERFACE,\r
                    &FvDevice->Fv\r
                    );\r
        ASSERT_EFI_ERROR (Status);\r
      } else {\r
        //\r
        // Free FvDevice Buffer for the corrupt FV image.\r
        //\r
        CoreFreePool (FvDevice);\r
      }\r
    }\r
  }\r
\r
  return;\r
}\r
\r
\r
\r
/**\r
  This routine is the driver initialization entry point.  It registers\r
  a notification function.  This notification function are responsible\r
  for building the FV stack dynamically.\r
\r
  @param  ImageHandle           The image handle.\r
  @param  SystemTable           The system table.\r
\r
  @retval EFI_SUCCESS           Function successfully returned.\r
\r
**/\r
EFI_STATUS\r
EFIAPI\r
FwVolDriverInit (\r
  IN EFI_HANDLE                   ImageHandle,\r
  IN EFI_SYSTEM_TABLE             *SystemTable\r
  )\r
{\r
  gEfiFwVolBlockEvent = EfiCreateProtocolNotifyEvent (\r
                          &gEfiFirmwareVolumeBlockProtocolGuid,\r
                          TPL_CALLBACK,\r
                          NotifyFwVolBlock,\r
                          NULL,\r
                          &gEfiFwVolBlockNotifyReg\r
                          );\r
  return EFI_SUCCESS;\r
}\r
\r
\r