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      1 /** @file
      2 
      3   The internal header file includes the common header files, defines
      4   internal structure and functions used by Ftw module.
      5 
      6 Copyright (c) 2006 - 2014, Intel Corporation. All rights reserved.<BR>
      7 This program and the accompanying materials
      8 are licensed and made available under the terms and conditions of the BSD License
      9 which accompanies this distribution.  The full text of the license may be found at
     10 http://opensource.org/licenses/bsd-license.php
     11 
     12 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
     13 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
     14 
     15 **/
     16 
     17 #ifndef _EFI_FAULT_TOLERANT_WRITE_H_
     18 #define _EFI_FAULT_TOLERANT_WRITE_H_
     19 
     20 #include <PiDxe.h>
     21 
     22 #include <Guid/SystemNvDataGuid.h>
     23 #include <Guid/ZeroGuid.h>
     24 #include <Protocol/FaultTolerantWrite.h>
     25 #include <Protocol/FirmwareVolumeBlock.h>
     26 #include <Protocol/SwapAddressRange.h>
     27 
     28 #include <Library/PcdLib.h>
     29 #include <Library/DebugLib.h>
     30 #include <Library/UefiLib.h>
     31 #include <Library/UefiDriverEntryPoint.h>
     32 #include <Library/BaseMemoryLib.h>
     33 #include <Library/MemoryAllocationLib.h>
     34 #include <Library/UefiBootServicesTableLib.h>
     35 #include <Library/ReportStatusCodeLib.h>
     36 
     37 //
     38 // Flash erase polarity is 1
     39 //
     40 #define FTW_ERASE_POLARITY  1
     41 
     42 #define FTW_ERASED_BYTE     ((UINT8) (255))
     43 #define FTW_POLARITY_REVERT ((UINT8) (255))
     44 
     45 #define HEADER_ALLOCATED  0x1
     46 #define WRITES_ALLOCATED  0x2
     47 #define WRITES_COMPLETED  0x4
     48 
     49 #define BOOT_BLOCK_UPDATE 0x1
     50 #define SPARE_COMPLETED   0x2
     51 #define DEST_COMPLETED    0x4
     52 
     53 #define FTW_BLOCKS(Length, BlockSize) ((UINTN) ((Length) / (BlockSize) + (((Length) & ((BlockSize) - 1)) ? 1 : 0)))
     54 
     55 #define FTW_DEVICE_SIGNATURE  SIGNATURE_32 ('F', 'T', 'W', 'D')
     56 
     57 //
     58 // EFI Fault tolerant protocol private data structure
     59 //
     60 typedef struct {
     61   UINTN                                   Signature;
     62   EFI_HANDLE                              Handle;
     63   EFI_FAULT_TOLERANT_WRITE_PROTOCOL       FtwInstance;
     64   EFI_PHYSICAL_ADDRESS                    WorkSpaceAddress;   // Base address of working space range in flash.
     65   EFI_PHYSICAL_ADDRESS                    SpareAreaAddress;   // Base address of spare range in flash.
     66   UINTN                                   WorkSpaceLength;    // Size of working space range in flash.
     67   UINTN                                   NumberOfWorkSpaceBlock; // Number of the blocks in work block for work space.
     68   UINTN                                   WorkBlockSize;      // Block size in bytes of the work blocks in flash
     69   UINTN                                   SpareAreaLength;    // Size of spare range in flash.
     70   UINTN                                   NumberOfSpareBlock; // Number of the blocks in spare block.
     71   UINTN                                   SpareBlockSize;     // Block size in bytes of the spare blocks in flash
     72   EFI_FAULT_TOLERANT_WORKING_BLOCK_HEADER *FtwWorkSpaceHeader;// Pointer to Working Space Header in memory buffer
     73   EFI_FAULT_TOLERANT_WRITE_HEADER         *FtwLastWriteHeader;// Pointer to last record header in memory buffer
     74   EFI_FAULT_TOLERANT_WRITE_RECORD         *FtwLastWriteRecord;// Pointer to last record in memory buffer
     75   EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL      *FtwFvBlock;        // FVB of working block
     76   EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL      *FtwBackupFvb;      // FVB of spare block
     77   EFI_LBA                                 FtwSpareLba;        // Start LBA of spare block
     78   EFI_LBA                                 FtwWorkBlockLba;    // Start LBA of working block that contains working space in its last block.
     79   UINTN                                   NumberOfWorkBlock;  // Number of the blocks in work block.
     80   EFI_LBA                                 FtwWorkSpaceLba;    // Start LBA of working space
     81   UINTN                                   FtwWorkSpaceBase;   // Offset into the FtwWorkSpaceLba block.
     82   UINTN                                   FtwWorkSpaceSize;   // Size of working space range that stores write record.
     83   EFI_LBA                                 FtwWorkSpaceLbaInSpare; // Start LBA of working space in spare block.
     84   UINTN                                   FtwWorkSpaceBaseInSpare;// Offset into the FtwWorkSpaceLbaInSpare block.
     85   UINT8                                   *FtwWorkSpace;      // Point to Work Space in memory buffer
     86   //
     87   // Following a buffer of FtwWorkSpace[FTW_WORK_SPACE_SIZE],
     88   // Allocated with EFI_FTW_DEVICE.
     89   //
     90 } EFI_FTW_DEVICE;
     91 
     92 #define FTW_CONTEXT_FROM_THIS(a)  CR (a, EFI_FTW_DEVICE, FtwInstance, FTW_DEVICE_SIGNATURE)
     93 
     94 //
     95 // Driver entry point
     96 //
     97 /**
     98   This function is the entry point of the Fault Tolerant Write driver.
     99 
    100   @param ImageHandle     A handle for the image that is initializing this driver
    101   @param SystemTable     A pointer to the EFI system table
    102 
    103   @return EFI_SUCCESS           FTW has finished the initialization
    104   @retval EFI_NOT_FOUND         Locate FVB protocol error
    105   @retval EFI_OUT_OF_RESOURCES  Allocate memory error
    106   @retval EFI_VOLUME_CORRUPTED  Firmware volume is error
    107   @retval EFI_ABORTED           FTW initialization error
    108 
    109 **/
    110 EFI_STATUS
    111 EFIAPI
    112 InitializeFaultTolerantWrite (
    113   IN EFI_HANDLE         ImageHandle,
    114   IN EFI_SYSTEM_TABLE   *SystemTable
    115   );
    116 
    117 //
    118 // Fault Tolerant Write Protocol API
    119 //
    120 
    121 /**
    122   Query the largest block that may be updated in a fault tolerant manner.
    123 
    124 
    125   @param This            Indicates a pointer to the calling context.
    126   @param BlockSize       A pointer to a caller allocated UINTN that is updated to
    127                          indicate the size of the largest block that can be updated.
    128 
    129   @return EFI_SUCCESS   The function completed successfully
    130 
    131 **/
    132 EFI_STATUS
    133 EFIAPI
    134 FtwGetMaxBlockSize (
    135   IN EFI_FAULT_TOLERANT_WRITE_PROTOCOL    *This,
    136   OUT UINTN                               *BlockSize
    137   );
    138 
    139 /**
    140   Allocates space for the protocol to maintain information about writes.
    141   Since writes must be completed in a fault tolerant manner and multiple
    142   updates will require more resources to be successful, this function
    143   enables the protocol to ensure that enough space exists to track
    144   information about the upcoming writes.
    145 
    146   All writes must be completed or aborted before another fault tolerant write can occur.
    147 
    148   @param This            Indicates a pointer to the calling context.
    149   @param CallerId        The GUID identifying the write.
    150   @param PrivateDataSize The size of the caller's private data
    151                          that must be recorded for each write.
    152   @param NumberOfWrites  The number of fault tolerant block writes
    153                          that will need to occur.
    154 
    155   @return EFI_SUCCESS        The function completed successfully
    156   @retval EFI_ABORTED        The function could not complete successfully.
    157   @retval EFI_ACCESS_DENIED  All allocated writes have not been completed.
    158 
    159 **/
    160 EFI_STATUS
    161 EFIAPI
    162 FtwAllocate (
    163   IN EFI_FAULT_TOLERANT_WRITE_PROTOCOL    *This,
    164   IN EFI_GUID                             *CallerId,
    165   IN UINTN                                PrivateDataSize,
    166   IN UINTN                                NumberOfWrites
    167   );
    168 
    169 /**
    170   Starts a target block update. This function will record data about write
    171   in fault tolerant storage and will complete the write in a recoverable
    172   manner, ensuring at all times that either the original contents or
    173   the modified contents are available.
    174 
    175 
    176   @param This            Calling context
    177   @param Lba             The logical block address of the target block.
    178   @param Offset          The offset within the target block to place the data.
    179   @param Length          The number of bytes to write to the target block.
    180   @param PrivateData     A pointer to private data that the caller requires to
    181                          complete any pending writes in the event of a fault.
    182   @param FvBlockHandle   The handle of FVB protocol that provides services for
    183                          reading, writing, and erasing the target block.
    184   @param Buffer          The data to write.
    185 
    186   @retval EFI_SUCCESS          The function completed successfully
    187   @retval EFI_ABORTED          The function could not complete successfully.
    188   @retval EFI_BAD_BUFFER_SIZE  The input data can't fit within the spare block.
    189                                Offset + *NumBytes > SpareAreaLength.
    190   @retval EFI_ACCESS_DENIED    No writes have been allocated.
    191   @retval EFI_OUT_OF_RESOURCES Cannot allocate enough memory resource.
    192   @retval EFI_NOT_FOUND        Cannot find FVB protocol by handle.
    193 
    194 **/
    195 EFI_STATUS
    196 EFIAPI
    197 FtwWrite (
    198   IN EFI_FAULT_TOLERANT_WRITE_PROTOCOL     *This,
    199   IN EFI_LBA                               Lba,
    200   IN UINTN                                 Offset,
    201   IN UINTN                                 Length,
    202   IN VOID                                  *PrivateData,
    203   IN EFI_HANDLE                            FvBlockHandle,
    204   IN VOID                                  *Buffer
    205   );
    206 
    207 /**
    208   Restarts a previously interrupted write. The caller must provide the
    209   block protocol needed to complete the interrupted write.
    210 
    211   @param This            Calling context.
    212   @param FvBlockHandle   The handle of FVB protocol that provides services for
    213                          reading, writing, and erasing the target block.
    214 
    215   @retval  EFI_SUCCESS          The function completed successfully
    216   @retval  EFI_ACCESS_DENIED    No pending writes exist
    217   @retval  EFI_NOT_FOUND        FVB protocol not found by the handle
    218   @retval  EFI_ABORTED          The function could not complete successfully
    219 
    220 **/
    221 EFI_STATUS
    222 EFIAPI
    223 FtwRestart (
    224   IN EFI_FAULT_TOLERANT_WRITE_PROTOCOL     *This,
    225   IN EFI_HANDLE                            FvBlockHandle
    226   );
    227 
    228 /**
    229   Aborts all previous allocated writes.
    230 
    231   @param  This                 Calling context
    232 
    233   @retval EFI_SUCCESS          The function completed successfully
    234   @retval EFI_ABORTED          The function could not complete successfully.
    235   @retval EFI_NOT_FOUND        No allocated writes exist.
    236 
    237 **/
    238 EFI_STATUS
    239 EFIAPI
    240 FtwAbort (
    241   IN EFI_FAULT_TOLERANT_WRITE_PROTOCOL     *This
    242   );
    243 
    244 /**
    245   Starts a target block update. This records information about the write
    246   in fault tolerant storage and will complete the write in a recoverable
    247   manner, ensuring at all times that either the original contents or
    248   the modified contents are available.
    249 
    250   @param This            Indicates a pointer to the calling context.
    251   @param CallerId        The GUID identifying the last write.
    252   @param Lba             The logical block address of the last write.
    253   @param Offset          The offset within the block of the last write.
    254   @param Length          The length of the last write.
    255   @param PrivateDataSize bytes from the private data
    256                          stored for this write.
    257   @param PrivateData     A pointer to a buffer. The function will copy
    258   @param Complete        A Boolean value with TRUE indicating
    259                          that the write was completed.
    260 
    261   @retval EFI_SUCCESS           The function completed successfully
    262   @retval EFI_ABORTED           The function could not complete successfully
    263   @retval EFI_NOT_FOUND         No allocated writes exist
    264   @retval EFI_BUFFER_TOO_SMALL  Input buffer is not larget enough
    265 
    266 **/
    267 EFI_STATUS
    268 EFIAPI
    269 FtwGetLastWrite (
    270   IN EFI_FAULT_TOLERANT_WRITE_PROTOCOL     *This,
    271   OUT EFI_GUID                             *CallerId,
    272   OUT EFI_LBA                              *Lba,
    273   OUT UINTN                                *Offset,
    274   OUT UINTN                                *Length,
    275   IN OUT UINTN                             *PrivateDataSize,
    276   OUT VOID                                 *PrivateData,
    277   OUT BOOLEAN                              *Complete
    278   );
    279 
    280 /**
    281   Erase spare block.
    282 
    283   @param FtwDevice        The private data of FTW driver
    284 
    285   @retval EFI_SUCCESS           The erase request was successfully completed.
    286   @retval EFI_ACCESS_DENIED     The firmware volume is in the WriteDisabled state.
    287   @retval EFI_DEVICE_ERROR      The block device is not functioning
    288                                 correctly and could not be written.
    289                                 The firmware device may have been
    290                                 partially erased.
    291   @retval EFI_INVALID_PARAMETER One or more of the LBAs listed
    292                                 in the variable argument list do
    293                                 not exist in the firmware volume.
    294 
    295 
    296 **/
    297 EFI_STATUS
    298 FtwEraseSpareBlock (
    299   IN EFI_FTW_DEVICE   *FtwDevice
    300   );
    301 
    302 /**
    303   Retrieve the proper FVB protocol interface by HANDLE.
    304 
    305 
    306   @param FvBlockHandle   The handle of FVB protocol that provides services for
    307                          reading, writing, and erasing the target block.
    308   @param FvBlock         The interface of FVB protocol
    309 
    310   @retval  EFI_SUCCESS   The function completed successfully
    311   @retval  EFI_ABORTED   The function could not complete successfully
    312 
    313 **/
    314 EFI_STATUS
    315 FtwGetFvbByHandle (
    316   IN EFI_HANDLE                           FvBlockHandle,
    317   OUT EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL  **FvBlock
    318   );
    319 
    320 /**
    321 
    322   Is it in working block?
    323 
    324   @param FtwDevice       The private data of FTW driver
    325   @param FvBlock         Fvb protocol instance
    326   @param Lba             The block specified
    327 
    328   @return A BOOLEAN value indicating in working block or not.
    329 
    330 **/
    331 BOOLEAN
    332 IsWorkingBlock (
    333   EFI_FTW_DEVICE                      *FtwDevice,
    334   EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL  *FvBlock,
    335   EFI_LBA                             Lba
    336   );
    337 
    338 /**
    339 
    340   Is it in boot block?
    341 
    342   @param FtwDevice       The private data of FTW driver
    343   @param FvBlock         Fvb protocol instance
    344 
    345   @return A BOOLEAN value indicating in boot block or not.
    346 
    347 **/
    348 BOOLEAN
    349 IsBootBlock (
    350   EFI_FTW_DEVICE                      *FtwDevice,
    351   EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL  *FvBlock
    352   );
    353 
    354 /**
    355   Copy the content of spare block to a target block. Size is FTW_BLOCK_SIZE.
    356   Spare block is accessed by FTW backup FVB protocol interface.
    357   Target block is accessed by FvBlock protocol interface.
    358 
    359 
    360   @param FtwDevice       The private data of FTW driver
    361   @param FvBlock         FVB Protocol interface to access target block
    362   @param Lba             Lba of the target block
    363   @param BlockSize       The size of the block
    364   @param NumberOfBlocks  The number of consecutive blocks starting with Lba
    365 
    366   @retval  EFI_SUCCESS               Spare block content is copied to target block
    367   @retval  EFI_INVALID_PARAMETER     Input parameter error
    368   @retval  EFI_OUT_OF_RESOURCES      Allocate memory error
    369   @retval  EFI_ABORTED               The function could not complete successfully
    370 
    371 **/
    372 EFI_STATUS
    373 FlushSpareBlockToTargetBlock (
    374   EFI_FTW_DEVICE                      *FtwDevice,
    375   EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL  *FvBlock,
    376   EFI_LBA                             Lba,
    377   UINTN                               BlockSize,
    378   UINTN                               NumberOfBlocks
    379   );
    380 
    381 /**
    382   Copy the content of spare block to working block. Size is FTW_BLOCK_SIZE.
    383   Spare block is accessed by FTW backup FVB protocol interface. LBA is
    384   FtwDevice->FtwSpareLba.
    385   Working block is accessed by FTW working FVB protocol interface. LBA is
    386   FtwDevice->FtwWorkBlockLba.
    387 
    388   Since the working block header is important when FTW initializes, the
    389   state of the operation should be handled carefully. The Crc value is
    390   calculated without STATE element.
    391 
    392   @param FtwDevice       The private data of FTW driver
    393 
    394   @retval  EFI_SUCCESS               Spare block content is copied to target block
    395   @retval  EFI_OUT_OF_RESOURCES      Allocate memory error
    396   @retval  EFI_ABORTED               The function could not complete successfully
    397 
    398 **/
    399 EFI_STATUS
    400 FlushSpareBlockToWorkingBlock (
    401   EFI_FTW_DEVICE                      *FtwDevice
    402   );
    403 
    404 /**
    405   Copy the content of spare block to a boot block. Size is FTW_BLOCK_SIZE.
    406   Spare block is accessed by FTW working FVB protocol interface.
    407   Target block is accessed by FvBlock protocol interface.
    408 
    409   FTW will do extra work on boot block update.
    410   FTW should depend on a protocol of EFI_ADDRESS_RANGE_SWAP_PROTOCOL,
    411   which is produced by a chipset driver.
    412   FTW updating boot block steps may be:
    413   1. GetRangeLocation(), if the Range is inside the boot block, FTW know
    414   that boot block will be update. It shall add a FLAG in the working block.
    415   2. When spare block is ready,
    416   3. SetSwapState(SWAPPED)
    417   4. erasing boot block,
    418   5. programming boot block until the boot block is ok.
    419   6. SetSwapState(UNSWAPPED)
    420   FTW shall not allow to update boot block when battery state is error.
    421 
    422   @param FtwDevice       The private data of FTW driver
    423 
    424   @retval EFI_SUCCESS             Spare block content is copied to boot block
    425   @retval EFI_INVALID_PARAMETER   Input parameter error
    426   @retval EFI_OUT_OF_RESOURCES    Allocate memory error
    427   @retval EFI_ABORTED             The function could not complete successfully
    428 
    429 **/
    430 EFI_STATUS
    431 FlushSpareBlockToBootBlock (
    432   EFI_FTW_DEVICE                      *FtwDevice
    433   );
    434 
    435 /**
    436   Update a bit of state on a block device. The location of the bit is
    437   calculated by the (Lba, Offset, bit). Here bit is determined by the
    438   the name of a certain bit.
    439 
    440 
    441   @param FvBlock         FVB Protocol interface to access SrcBlock and DestBlock
    442   @param BlockSize       The size of the block
    443   @param Lba             Lba of a block
    444   @param Offset          Offset on the Lba
    445   @param NewBit          New value that will override the old value if it can be change
    446 
    447   @retval  EFI_SUCCESS    A state bit has been updated successfully
    448   @retval  Others         Access block device error.
    449                           Notes:
    450                           Assume all bits of State are inside the same BYTE.
    451   @retval  EFI_ABORTED    Read block fail
    452 
    453 **/
    454 EFI_STATUS
    455 FtwUpdateFvState (
    456   IN EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL  *FvBlock,
    457   IN UINTN                               BlockSize,
    458   IN EFI_LBA                             Lba,
    459   IN UINTN                               Offset,
    460   IN UINT8                               NewBit
    461   );
    462 
    463 /**
    464   Get the last Write Header pointer.
    465   The last write header is the header whose 'complete' state hasn't been set.
    466   After all, this header may be a EMPTY header entry for next Allocate.
    467 
    468 
    469   @param FtwWorkSpaceHeader Pointer of the working block header
    470   @param FtwWorkSpaceSize   Size of the work space
    471   @param FtwWriteHeader     Pointer to retrieve the last write header
    472 
    473   @retval  EFI_SUCCESS      Get the last write record successfully
    474   @retval  EFI_ABORTED      The FTW work space is damaged
    475 
    476 **/
    477 EFI_STATUS
    478 FtwGetLastWriteHeader (
    479   IN EFI_FAULT_TOLERANT_WORKING_BLOCK_HEADER  *FtwWorkSpaceHeader,
    480   IN UINTN                                    FtwWorkSpaceSize,
    481   OUT EFI_FAULT_TOLERANT_WRITE_HEADER         **FtwWriteHeader
    482   );
    483 
    484 /**
    485   Get the last Write Record pointer. The last write Record is the Record
    486   whose DestinationCompleted state hasn't been set. After all, this Record
    487   may be a EMPTY record entry for next write.
    488 
    489 
    490   @param FtwWriteHeader  Pointer to the write record header
    491   @param FtwWriteRecord  Pointer to retrieve the last write record
    492 
    493   @retval EFI_SUCCESS        Get the last write record successfully
    494   @retval EFI_ABORTED        The FTW work space is damaged
    495 
    496 **/
    497 EFI_STATUS
    498 FtwGetLastWriteRecord (
    499   IN EFI_FAULT_TOLERANT_WRITE_HEADER          *FtwWriteHeader,
    500   OUT EFI_FAULT_TOLERANT_WRITE_RECORD         **FtwWriteRecord
    501   );
    502 
    503 /**
    504   To check if FtwRecord is the first record of FtwHeader.
    505 
    506   @param FtwHeader  Pointer to the write record header
    507   @param FtwRecord  Pointer to the write record
    508 
    509   @retval TRUE      FtwRecord is the first Record of the FtwHeader
    510   @retval FALSE     FtwRecord is not the first Record of the FtwHeader
    511 
    512 **/
    513 BOOLEAN
    514 IsFirstRecordOfWrites (
    515   IN EFI_FAULT_TOLERANT_WRITE_HEADER    *FtwHeader,
    516   IN EFI_FAULT_TOLERANT_WRITE_RECORD    *FtwRecord
    517   );
    518 
    519 /**
    520   To check if FtwRecord is the last record of FtwHeader. Because the
    521   FtwHeader has NumberOfWrites & PrivateDataSize, the FtwRecord can be
    522   determined if it is the last record of FtwHeader.
    523 
    524   @param FtwHeader  Pointer to the write record header
    525   @param FtwRecord  Pointer to the write record
    526 
    527   @retval TRUE      FtwRecord is the last Record of the FtwHeader
    528   @retval FALSE     FtwRecord is not the last Record of the FtwHeader
    529 
    530 **/
    531 BOOLEAN
    532 IsLastRecordOfWrites (
    533   IN EFI_FAULT_TOLERANT_WRITE_HEADER    *FtwHeader,
    534   IN EFI_FAULT_TOLERANT_WRITE_RECORD    *FtwRecord
    535   );
    536 
    537 /**
    538   To check if FtwRecord is the first record of FtwHeader.
    539 
    540   @param FtwHeader  Pointer to the write record header
    541   @param FtwRecord  Pointer to retrieve the previous write record
    542 
    543   @retval EFI_ACCESS_DENIED  Input record is the first record, no previous record is return.
    544   @retval EFI_SUCCESS        The previous write record is found.
    545 
    546 **/
    547 EFI_STATUS
    548 GetPreviousRecordOfWrites (
    549   IN     EFI_FAULT_TOLERANT_WRITE_HEADER    *FtwHeader,
    550   IN OUT EFI_FAULT_TOLERANT_WRITE_RECORD    **FtwRecord
    551   );
    552 
    553 /**
    554 
    555   Check whether a flash buffer is erased.
    556 
    557   @param Buffer          Buffer to check
    558   @param BufferSize      Size of the buffer
    559 
    560   @return A BOOLEAN value indicating erased or not.
    561 
    562 **/
    563 BOOLEAN
    564 IsErasedFlashBuffer (
    565   IN UINT8           *Buffer,
    566   IN UINTN           BufferSize
    567   );
    568 /**
    569   Initialize a work space when there is no work space.
    570 
    571   @param WorkingHeader   Pointer of working block header
    572 
    573   @retval  EFI_SUCCESS    The function completed successfully
    574   @retval  EFI_ABORTED    The function could not complete successfully.
    575 
    576 **/
    577 EFI_STATUS
    578 InitWorkSpaceHeader (
    579   IN EFI_FAULT_TOLERANT_WORKING_BLOCK_HEADER *WorkingHeader
    580   );
    581 /**
    582   Read from working block to refresh the work space in memory.
    583 
    584   @param FtwDevice   Point to private data of FTW driver
    585 
    586   @retval  EFI_SUCCESS    The function completed successfully
    587   @retval  EFI_ABORTED    The function could not complete successfully.
    588 
    589 **/
    590 EFI_STATUS
    591 WorkSpaceRefresh (
    592   IN EFI_FTW_DEVICE  *FtwDevice
    593   );
    594 /**
    595   Check to see if it is a valid work space.
    596 
    597 
    598   @param WorkingHeader   Pointer of working block header
    599 
    600   @retval  EFI_SUCCESS    The function completed successfully
    601   @retval  EFI_ABORTED    The function could not complete successfully.
    602 
    603 **/
    604 BOOLEAN
    605 IsValidWorkSpace (
    606   IN EFI_FAULT_TOLERANT_WORKING_BLOCK_HEADER *WorkingHeader
    607   );
    608 /**
    609   Reclaim the work space on the working block.
    610 
    611   @param FtwDevice       Point to private data of FTW driver
    612   @param PreserveRecord  Whether to preserve the working record is needed
    613 
    614   @retval EFI_SUCCESS            The function completed successfully
    615   @retval EFI_OUT_OF_RESOURCES   Allocate memory error
    616   @retval EFI_ABORTED            The function could not complete successfully
    617 
    618 **/
    619 EFI_STATUS
    620 FtwReclaimWorkSpace (
    621   IN EFI_FTW_DEVICE  *FtwDevice,
    622   IN BOOLEAN         PreserveRecord
    623   );
    624 
    625 /**
    626 
    627   Get firmware volume block by address.
    628 
    629 
    630   @param Address         Address specified the block
    631   @param FvBlock         The block caller wanted
    632 
    633   @retval  EFI_SUCCESS    The protocol instance if found.
    634   @retval  EFI_NOT_FOUND  Block not found
    635 
    636 **/
    637 EFI_HANDLE
    638 GetFvbByAddress (
    639   IN  EFI_PHYSICAL_ADDRESS               Address,
    640   OUT EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL **FvBlock
    641   );
    642 
    643 /**
    644   Retrieve the proper Swap Address Range protocol interface.
    645 
    646   @param[out] SarProtocol       The interface of SAR protocol
    647 
    648   @retval EFI_SUCCESS           The SAR protocol instance was found and returned in SarProtocol.
    649   @retval EFI_NOT_FOUND         The SAR protocol instance was not found.
    650   @retval EFI_INVALID_PARAMETER SarProtocol is NULL.
    651 
    652 **/
    653 EFI_STATUS
    654 FtwGetSarProtocol (
    655   OUT VOID                                **SarProtocol
    656   );
    657 
    658 /**
    659   Function returns an array of handles that support the FVB protocol
    660   in a buffer allocated from pool.
    661 
    662   @param[out]  NumberHandles    The number of handles returned in Buffer.
    663   @param[out]  Buffer           A pointer to the buffer to return the requested
    664                                 array of  handles that support FVB protocol.
    665 
    666   @retval EFI_SUCCESS           The array of handles was returned in Buffer, and the number of
    667                                 handles in Buffer was returned in NumberHandles.
    668   @retval EFI_NOT_FOUND         No FVB handle was found.
    669   @retval EFI_OUT_OF_RESOURCES  There is not enough pool memory to store the matching results.
    670   @retval EFI_INVALID_PARAMETER NumberHandles is NULL or Buffer is NULL.
    671 
    672 **/
    673 EFI_STATUS
    674 GetFvbCountAndBuffer (
    675   OUT UINTN                               *NumberHandles,
    676   OUT EFI_HANDLE                          **Buffer
    677   );
    678 
    679 
    680 /**
    681   Allocate private data for FTW driver and initialize it.
    682 
    683   @param[out] FtwData           Pointer to the FTW device structure
    684 
    685   @retval EFI_SUCCESS           Initialize the FTW device successfully.
    686   @retval EFI_OUT_OF_RESOURCES  Allocate memory error
    687   @retval EFI_INVALID_PARAMETER Workspace or Spare block does not exist
    688 
    689 **/
    690 EFI_STATUS
    691 InitFtwDevice (
    692   OUT EFI_FTW_DEVICE               **FtwData
    693   );
    694 
    695 
    696 /**
    697   Initialization for Fault Tolerant Write is done in this handler.
    698 
    699   @param[in, out] FtwDevice     Pointer to the FTW device structure
    700 
    701   @retval EFI_SUCCESS           Initialize the FTW protocol successfully.
    702   @retval EFI_NOT_FOUND         No proper FVB protocol was found.
    703 
    704 **/
    705 EFI_STATUS
    706 InitFtwProtocol (
    707   IN OUT EFI_FTW_DEVICE               *FtwDevice
    708   );
    709 
    710 /**
    711   Initialize a local work space header.
    712 
    713   Since Signature and WriteQueueSize have been known, Crc can be calculated out,
    714   then the work space header will be fixed.
    715 **/
    716 VOID
    717 InitializeLocalWorkSpaceHeader (
    718   VOID
    719   );
    720 
    721 /**
    722   Read work space data from work block or spare block.
    723 
    724   @param FvBlock        FVB Protocol interface to access the block.
    725   @param BlockSize      The size of the block.
    726   @param Lba            Lba of the block.
    727   @param Offset         The offset within the block.
    728   @param Length         The number of bytes to read from the block.
    729   @param Buffer         The data is read.
    730 
    731   @retval EFI_SUCCESS   The function completed successfully.
    732   @retval EFI_ABORTED   The function could not complete successfully.
    733 
    734 **/
    735 EFI_STATUS
    736 ReadWorkSpaceData (
    737   IN EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL *FvBlock,
    738   IN UINTN                              BlockSize,
    739   IN EFI_LBA                            Lba,
    740   IN UINTN                              Offset,
    741   IN UINTN                              Length,
    742   OUT UINT8                             *Buffer
    743   );
    744 
    745 /**
    746   Write data to work block.
    747 
    748   @param FvBlock        FVB Protocol interface to access the block.
    749   @param BlockSize      The size of the block.
    750   @param Lba            Lba of the block.
    751   @param Offset         The offset within the block to place the data.
    752   @param Length         The number of bytes to write to the block.
    753   @param Buffer         The data to write.
    754 
    755   @retval EFI_SUCCESS   The function completed successfully.
    756   @retval EFI_ABORTED   The function could not complete successfully.
    757 
    758 **/
    759 EFI_STATUS
    760 WriteWorkSpaceData (
    761   IN EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL *FvBlock,
    762   IN UINTN                              BlockSize,
    763   IN EFI_LBA                            Lba,
    764   IN UINTN                              Offset,
    765   IN UINTN                              Length,
    766   IN UINT8                              *Buffer
    767   );
    768 
    769 #endif
    770