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audk/MdeModulePkg/Universal/FaultTolerantWriteDxe/FaultTolerantWrite.h

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/** @file
The internal header file includes the common header files, defines
internal structure and functions used by FtwLite module.
Copyright (c) 2006 - 2010, Intel Corporation. All rights reserved.<BR>
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 _EFI_FAULT_TOLERANT_WRITE_H_
#define _EFI_FAULT_TOLERANT_WRITE_H_
#include <PiDxe.h>
#include <Guid/SystemNvDataGuid.h>
#include <Protocol/FaultTolerantWrite.h>
#include <Protocol/FirmwareVolumeBlock.h>
#include <Protocol/SwapAddressRange.h>
#include <Library/PcdLib.h>
#include <Library/DebugLib.h>
#include <Library/UefiLib.h>
#include <Library/UefiDriverEntryPoint.h>
#include <Library/BaseMemoryLib.h>
#include <Library/MemoryAllocationLib.h>
#include <Library/UefiBootServicesTableLib.h>
//
// Flash erase polarity is 1
//
#define FTW_ERASE_POLARITY 1
#define FTW_VALID_STATE 0
#define FTW_INVALID_STATE 1
#define FTW_ERASED_BYTE ((UINT8) (255))
#define FTW_POLARITY_REVERT ((UINT8) (255))
//
// EFI Fault tolerant block update write queue entry
//
typedef struct {
UINT8 HeaderAllocated : 1;
UINT8 WritesAllocated : 1;
UINT8 Complete : 1;
#define HEADER_ALLOCATED 0x1
#define WRITES_ALLOCATED 0x2
#define WRITES_COMPLETED 0x4
UINT8 Reserved : 5;
EFI_GUID CallerId;
UINTN NumberOfWrites;
UINTN PrivateDataSize;
} EFI_FAULT_TOLERANT_WRITE_HEADER;
//
// EFI Fault tolerant block update write queue record
//
typedef struct {
UINT8 BootBlockUpdate : 1;
UINT8 SpareComplete : 1;
UINT8 DestinationComplete : 1;
#define BOOT_BLOCK_UPDATE 0x1
#define SPARE_COMPLETED 0x2
#define DEST_COMPLETED 0x4
UINT8 Reserved : 5;
EFI_LBA Lba;
UINTN Offset;
UINTN Length;
EFI_PHYSICAL_ADDRESS FvBaseAddress;
//
// UINT8 PrivateData[PrivateDataSize]
//
} EFI_FAULT_TOLERANT_WRITE_RECORD;
#define RECORD_SIZE(PrivateDataSize) (sizeof (EFI_FAULT_TOLERANT_WRITE_RECORD) + PrivateDataSize)
#define RECORD_TOTAL_SIZE(NumberOfWrites, PrivateDataSize) \
((NumberOfWrites) * (sizeof (EFI_FAULT_TOLERANT_WRITE_RECORD) + PrivateDataSize))
#define WRITE_TOTAL_SIZE(NumberOfWrites, PrivateDataSize) \
( \
sizeof (EFI_FAULT_TOLERANT_WRITE_HEADER) + (NumberOfWrites) * \
(sizeof (EFI_FAULT_TOLERANT_WRITE_RECORD) + PrivateDataSize) \
)
#define FTW_DEVICE_SIGNATURE SIGNATURE_32 ('F', 'T', 'W', 'D')
//
// EFI Fault tolerant protocol private data structure
//
typedef struct {
UINTN Signature;
EFI_HANDLE Handle;
EFI_FAULT_TOLERANT_WRITE_PROTOCOL FtwInstance;
EFI_PHYSICAL_ADDRESS WorkSpaceAddress; // Base address of working space range in flash.
EFI_PHYSICAL_ADDRESS SpareAreaAddress; // Base address of spare range in flash.
UINTN WorkSpaceLength; // Size of working space range in flash.
UINTN SpareAreaLength; // Size of spare range in flash.
UINTN NumberOfSpareBlock; // Number of the blocks in spare block.
UINTN BlockSize; // Block size in bytes of the blocks in flash
EFI_FAULT_TOLERANT_WORKING_BLOCK_HEADER *FtwWorkSpaceHeader;// Pointer to Working Space Header in memory buffer
EFI_FAULT_TOLERANT_WRITE_HEADER *FtwLastWriteHeader;// Pointer to last record header in memory buffer
EFI_FAULT_TOLERANT_WRITE_RECORD *FtwLastWriteRecord;// Pointer to last record in memory buffer
EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL *FtwFvBlock; // FVB of working block
EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL *FtwBackupFvb; // FVB of spare block
EFI_LBA FtwSpareLba; // Start LBA of spare block
EFI_LBA FtwWorkBlockLba; // Start LBA of working block that contains working space in its last block.
EFI_LBA FtwWorkSpaceLba; // Start LBA of working space
UINTN FtwWorkSpaceBase; // Offset into the FtwWorkSpaceLba block.
UINTN FtwWorkSpaceSize; // Size of working space range that stores write record.
UINT8 *FtwWorkSpace; // Point to Work Space in memory buffer
//
// Following a buffer of FtwWorkSpace[FTW_WORK_SPACE_SIZE],
// Allocated with EFI_FTW_DEVICE.
//
} EFI_FTW_DEVICE;
#define FTW_CONTEXT_FROM_THIS(a) CR (a, EFI_FTW_DEVICE, FtwInstance, FTW_DEVICE_SIGNATURE)
//
// Driver entry point
//
/**
This function is the entry point of the Fault Tolerant Write driver.
@param ImageHandle A handle for the image that is initializing this driver
@param SystemTable A pointer to the EFI system table
@return EFI_SUCCESS FTW has finished the initialization
@retval EFI_NOT_FOUND Locate FVB protocol error
@retval EFI_OUT_OF_RESOURCES Allocate memory error
@retval EFI_VOLUME_CORRUPTED Firmware volume is error
@retval EFI_ABORTED FTW initialization error
**/
EFI_STATUS
EFIAPI
InitializeFaultTolerantWrite (
IN EFI_HANDLE ImageHandle,
IN EFI_SYSTEM_TABLE *SystemTable
);
//
// Fault Tolerant Write Protocol API
//
/**
Query the largest block that may be updated in a fault tolerant manner.
@param This Indicates a pointer to the calling context.
@param BlockSize A pointer to a caller allocated UINTN that is updated to
indicate the size of the largest block that can be updated.
@return EFI_SUCCESS The function completed successfully
**/
EFI_STATUS
EFIAPI
FtwGetMaxBlockSize (
IN EFI_FAULT_TOLERANT_WRITE_PROTOCOL *This,
OUT UINTN *BlockSize
);
/**
Allocates space for the protocol to maintain information about writes.
Since writes must be completed in a fault tolerant manner and multiple
updates will require more resources to be successful, this function
enables the protocol to ensure that enough space exists to track
information about the upcoming writes.
All writes must be completed or aborted before another fault tolerant write can occur.
@param This Indicates a pointer to the calling context.
@param CallerId The GUID identifying the write.
@param PrivateDataSize The size of the caller's private data
that must be recorded for each write.
@param NumberOfWrites The number of fault tolerant block writes
that will need to occur.
@return EFI_SUCCESS The function completed successfully
@retval EFI_ABORTED The function could not complete successfully.
@retval EFI_ACCESS_DENIED All allocated writes have not been completed.
**/
EFI_STATUS
EFIAPI
FtwAllocate (
IN EFI_FAULT_TOLERANT_WRITE_PROTOCOL *This,
IN EFI_GUID *CallerId,
IN UINTN PrivateDataSize,
IN UINTN NumberOfWrites
);
/**
Starts a target block update. This function will record data about write
in fault tolerant storage and will complete the write in a recoverable
manner, ensuring at all times that either the original contents or
the modified contents are available.
@param This Calling context
@param Lba The logical block address of the target block.
@param Offset The offset within the target block to place the data.
@param Length The number of bytes to write to the target block.
@param PrivateData A pointer to private data that the caller requires to
complete any pending writes in the event of a fault.
@param FvBlockHandle The handle of FVB protocol that provides services for
reading, writing, and erasing the target block.
@param Buffer The data to write.
@retval EFI_SUCCESS The function completed successfully
@retval EFI_ABORTED The function could not complete successfully.
@retval EFI_BAD_BUFFER_SIZE The input data can't fit within the spare block.
Offset + *NumBytes > SpareAreaLength.
@retval EFI_ACCESS_DENIED No writes have been allocated.
@retval EFI_OUT_OF_RESOURCES Cannot allocate enough memory resource.
@retval EFI_NOT_FOUND Cannot find FVB protocol by handle.
**/
EFI_STATUS
EFIAPI
FtwWrite (
IN EFI_FAULT_TOLERANT_WRITE_PROTOCOL *This,
IN EFI_LBA Lba,
IN UINTN Offset,
IN UINTN Length,
IN VOID *PrivateData,
IN EFI_HANDLE FvBlockHandle,
IN VOID *Buffer
);
/**
Restarts a previously interrupted write. The caller must provide the
block protocol needed to complete the interrupted write.
@param This Calling context.
@param FvBlockHandle The handle of FVB protocol that provides services for
reading, writing, and erasing the target block.
@retval EFI_SUCCESS The function completed successfully
@retval EFI_ACCESS_DENIED No pending writes exist
@retval EFI_NOT_FOUND FVB protocol not found by the handle
@retval EFI_ABORTED The function could not complete successfully
**/
EFI_STATUS
EFIAPI
FtwRestart (
IN EFI_FAULT_TOLERANT_WRITE_PROTOCOL *This,
IN EFI_HANDLE FvBlockHandle
);
/**
Aborts all previous allocated writes.
@param This Calling context
@retval EFI_SUCCESS The function completed successfully
@retval EFI_ABORTED The function could not complete successfully.
@retval EFI_NOT_FOUND No allocated writes exist.
**/
EFI_STATUS
EFIAPI
FtwAbort (
IN EFI_FAULT_TOLERANT_WRITE_PROTOCOL *This
);
/**
Starts a target block update. This records information about the write
in fault tolerant storage and will complete the write in a recoverable
manner, ensuring at all times that either the original contents or
the modified contents are available.
@param This Indicates a pointer to the calling context.
@param CallerId The GUID identifying the last write.
@param Lba The logical block address of the last write.
@param Offset The offset within the block of the last write.
@param Length The length of the last write.
@param PrivateDataSize bytes from the private data
stored for this write.
@param PrivateData A pointer to a buffer. The function will copy
@param Complete A Boolean value with TRUE indicating
that the write was completed.
@retval EFI_SUCCESS The function completed successfully
@retval EFI_ABORTED The function could not complete successfully
@retval EFI_NOT_FOUND No allocated writes exist
@retval EFI_BUFFER_TOO_SMALL Input buffer is not larget enough
**/
EFI_STATUS
EFIAPI
FtwGetLastWrite (
IN EFI_FAULT_TOLERANT_WRITE_PROTOCOL *This,
OUT EFI_GUID *CallerId,
OUT EFI_LBA *Lba,
OUT UINTN *Offset,
OUT UINTN *Length,
IN OUT UINTN *PrivateDataSize,
OUT VOID *PrivateData,
OUT BOOLEAN *Complete
);
/**
Erase spare block.
@param FtwDevice The private data of FTW driver
@retval EFI_SUCCESS The erase request was successfully completed.
@retval EFI_ACCESS_DENIED The firmware volume is in the WriteDisabled state.
@retval EFI_DEVICE_ERROR The block device is not functioning
correctly and could not be written.
The firmware device may have been
partially erased.
@retval EFI_INVALID_PARAMETER One or more of the LBAs listed
in the variable argument list do
not exist in the firmware volume.
**/
EFI_STATUS
FtwEraseSpareBlock (
IN EFI_FTW_DEVICE *FtwDevice
);
/**
Retrive the proper FVB protocol interface by HANDLE.
@param FvBlockHandle The handle of FVB protocol that provides services for
reading, writing, and erasing the target block.
@param FvBlock The interface of FVB protocol
@retval EFI_SUCCESS The function completed successfully
@retval EFI_ABORTED The function could not complete successfully
**/
EFI_STATUS
FtwGetFvbByHandle (
IN EFI_HANDLE FvBlockHandle,
OUT EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL **FvBlock
);
/**
Is it in working block?
@param FtwDevice The private data of FTW driver
@param FvBlock Fvb protocol instance
@param Lba The block specified
@return A BOOLEAN value indicating in working block or not.
**/
BOOLEAN
IsWorkingBlock (
EFI_FTW_DEVICE *FtwDevice,
EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL *FvBlock,
EFI_LBA Lba
);
/**
Is it in boot block?
@param FtwDevice The private data of FTW driver
@param FvBlock Fvb protocol instance
@param Lba The block specified
@return A BOOLEAN value indicating in boot block or not.
**/
BOOLEAN
IsBootBlock (
EFI_FTW_DEVICE *FtwDevice,
EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL *FvBlock,
EFI_LBA Lba
);
/**
Copy the content of spare block to a target block. Size is FTW_BLOCK_SIZE.
Spare block is accessed by FTW backup FVB protocol interface. LBA is 1.
Target block is accessed by FvbBlock protocol interface. LBA is Lba.
@param FtwDevice The private data of FTW driver
@param FvBlock FVB Protocol interface to access target block
@param Lba Lba of the target block
@retval EFI_SUCCESS Spare block content is copied to target block
@retval EFI_INVALID_PARAMETER Input parameter error
@retval EFI_OUT_OF_RESOURCES Allocate memory error
@retval EFI_ABORTED The function could not complete successfully
**/
EFI_STATUS
FlushSpareBlockToTargetBlock (
EFI_FTW_DEVICE *FtwDevice,
EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL *FvBlock,
EFI_LBA Lba
);
/**
Copy the content of spare block to working block. Size is FTW_BLOCK_SIZE.
Spare block is accessed by FTW backup FVB protocol interface. LBA is
FtwDevice->FtwSpareLba.
Working block is accessed by FTW working FVB protocol interface. LBA is
FtwDevice->FtwWorkBlockLba.
Since the working block header is important when FTW initializes, the
state of the operation should be handled carefully. The Crc value is
calculated without STATE element.
@param FtwDevice The private data of FTW driver
@retval EFI_SUCCESS Spare block content is copied to target block
@retval EFI_OUT_OF_RESOURCES Allocate memory error
@retval EFI_ABORTED The function could not complete successfully
**/
EFI_STATUS
FlushSpareBlockToWorkingBlock (
EFI_FTW_DEVICE *FtwDevice
);
/**
Copy the content of spare block to a boot block. Size is FTW_BLOCK_SIZE.
Spare block is accessed by FTW working FVB protocol interface. LBA is 1.
Target block is accessed by FvbBlock protocol interface. LBA is Lba.
FTW will do extra work on boot block update.
FTW should depend on a protocol of EFI_ADDRESS_RANGE_SWAP_PROTOCOL,
which is produced by a chipset driver.
FTW updating boot block steps may be:
1. GetRangeLocation(), if the Range is inside the boot block, FTW know
that boot block will be update. It shall add a FLAG in the working block.
2. When spare block is ready,
3. SetSwapState(EFI_SWAPPED)
4. erasing boot block,
5. programming boot block until the boot block is ok.
6. SetSwapState(UNSWAPPED)
FTW shall not allow to update boot block when battery state is error.
@param FtwDevice The private data of FTW driver
@retval EFI_SUCCESS Spare block content is copied to boot block
@retval EFI_INVALID_PARAMETER Input parameter error
@retval EFI_OUT_OF_RESOURCES Allocate memory error
@retval EFI_ABORTED The function could not complete successfully
**/
EFI_STATUS
FlushSpareBlockToBootBlock (
EFI_FTW_DEVICE *FtwDevice
);
/**
Update a bit of state on a block device. The location of the bit is
calculated by the (Lba, Offset, bit). Here bit is determined by the
the name of a certain bit.
@param FvBlock FVB Protocol interface to access SrcBlock and DestBlock
@param Lba Lba of a block
@param Offset Offset on the Lba
@param NewBit New value that will override the old value if it can be change
@retval EFI_SUCCESS A state bit has been updated successfully
@retval Others Access block device error.
Notes:
Assume all bits of State are inside the same BYTE.
@retval EFI_ABORTED Read block fail
**/
EFI_STATUS
FtwUpdateFvState (
IN EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL *FvBlock,
IN EFI_LBA Lba,
IN UINTN Offset,
IN UINT8 NewBit
);
/**
Get the last Write Header pointer.
The last write header is the header whose 'complete' state hasn't been set.
After all, this header may be a EMPTY header entry for next Allocate.
@param FtwWorkSpaceHeader Pointer of the working block header
@param FtwWorkSpaceSize Size of the work space
@param FtwWriteHeader Pointer to retrieve the last write header
@retval EFI_SUCCESS Get the last write record successfully
@retval EFI_ABORTED The FTW work space is damaged
**/
EFI_STATUS
FtwGetLastWriteHeader (
IN EFI_FAULT_TOLERANT_WORKING_BLOCK_HEADER *FtwWorkSpaceHeader,
IN UINTN FtwWorkSpaceSize,
OUT EFI_FAULT_TOLERANT_WRITE_HEADER **FtwWriteHeader
);
/**
Get the last Write Record pointer. The last write Record is the Record
whose DestinationCompleted state hasn't been set. After all, this Record
may be a EMPTY record entry for next write.
@param FtwWriteHeader Pointer to the write record header
@param FtwWriteRecord Pointer to retrieve the last write record
@retval EFI_SUCCESS Get the last write record successfully
@retval EFI_ABORTED The FTW work space is damaged
**/
EFI_STATUS
FtwGetLastWriteRecord (
IN EFI_FAULT_TOLERANT_WRITE_HEADER *FtwWriteHeader,
OUT EFI_FAULT_TOLERANT_WRITE_RECORD **FtwWriteRecord
);
/**
To check if FtwRecord is the first record of FtwHeader.
@param FtwHeader Pointer to the write record header
@param FtwRecord Pointer to the write record
@retval TRUE FtwRecord is the first Record of the FtwHeader
@retval FALSE FtwRecord is not the first Record of the FtwHeader
**/
BOOLEAN
IsFirstRecordOfWrites (
IN EFI_FAULT_TOLERANT_WRITE_HEADER *FtwHeader,
IN EFI_FAULT_TOLERANT_WRITE_RECORD *FtwRecord
);
/**
To check if FtwRecord is the last record of FtwHeader. Because the
FtwHeader has NumberOfWrites & PrivateDataSize, the FtwRecord can be
determined if it is the last record of FtwHeader.
@param FtwHeader Pointer to the write record header
@param FtwRecord Pointer to the write record
@retval TRUE FtwRecord is the last Record of the FtwHeader
@retval FALSE FtwRecord is not the last Record of the FtwHeader
**/
BOOLEAN
IsLastRecordOfWrites (
IN EFI_FAULT_TOLERANT_WRITE_HEADER *FtwHeader,
IN EFI_FAULT_TOLERANT_WRITE_RECORD *FtwRecord
);
/**
To check if FtwRecord is the first record of FtwHeader.
@param FtwHeader Pointer to the write record header
@param FtwRecord Pointer to retrieve the previous write record
@retval EFI_ACCESS_DENIED Input record is the first record, no previous record is return.
@retval EFI_SUCCESS The previous write record is found.
**/
EFI_STATUS
GetPreviousRecordOfWrites (
IN EFI_FAULT_TOLERANT_WRITE_HEADER *FtwHeader,
IN OUT EFI_FAULT_TOLERANT_WRITE_RECORD **FtwRecord
);
/**
Check whether a flash buffer is erased.
@param Buffer Buffer to check
@param BufferSize Size of the buffer
@return A BOOLEAN value indicating erased or not.
**/
BOOLEAN
IsErasedFlashBuffer (
IN UINT8 *Buffer,
IN UINTN BufferSize
);
/**
Initialize a work space when there is no work space.
@param WorkingHeader Pointer of working block header
@retval EFI_SUCCESS The function completed successfully
@retval EFI_ABORTED The function could not complete successfully.
**/
EFI_STATUS
InitWorkSpaceHeader (
IN EFI_FAULT_TOLERANT_WORKING_BLOCK_HEADER *WorkingHeader
);
/**
Read from working block to refresh the work space in memory.
@param FtwDevice Point to private data of FTW driver
@retval EFI_SUCCESS The function completed successfully
@retval EFI_ABORTED The function could not complete successfully.
**/
EFI_STATUS
WorkSpaceRefresh (
IN EFI_FTW_DEVICE *FtwDevice
);
/**
Check to see if it is a valid work space.
@param WorkingHeader Pointer of working block header
@retval EFI_SUCCESS The function completed successfully
@retval EFI_ABORTED The function could not complete successfully.
**/
BOOLEAN
IsValidWorkSpace (
IN EFI_FAULT_TOLERANT_WORKING_BLOCK_HEADER *WorkingHeader
);
/**
Reclaim the work space on the working block.
@param FtwDevice Point to private data of FTW driver
@param PreserveRecord Whether to preserve the working record is needed
@retval EFI_SUCCESS The function completed successfully
@retval EFI_OUT_OF_RESOURCES Allocate memory error
@retval EFI_ABORTED The function could not complete successfully
**/
EFI_STATUS
FtwReclaimWorkSpace (
IN EFI_FTW_DEVICE *FtwDevice,
IN BOOLEAN PreserveRecord
);
/**
Get firmware block by address.
@param Address Address specified the block
@param FvBlock The block caller wanted
@retval EFI_SUCCESS The protocol instance if found.
@retval EFI_NOT_FOUND Block not found
**/
EFI_HANDLE
GetFvbByAddress (
IN EFI_PHYSICAL_ADDRESS Address,
OUT EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL **FvBlock
);
/**
Retrive the proper Swap Address Range protocol interface.
@param[out] SarProtocol The interface of SAR protocol
@retval EFI_SUCCESS The SAR protocol instance was found and returned in SarProtocol.
@retval EFI_NOT_FOUND The SAR protocol instance was not found.
@retval EFI_INVALID_PARAMETER SarProtocol is NULL.
**/
EFI_STATUS
FtwGetSarProtocol (
OUT VOID **SarProtocol
);
/**
Function returns an array of handles that support the FVB protocol
in a buffer allocated from pool.
@param[out] NumberHandles The number of handles returned in Buffer.
@param[out] Buffer A pointer to the buffer to return the requested
array of handles that support FVB protocol.
@retval EFI_SUCCESS The array of handles was returned in Buffer, and the number of
handles in Buffer was returned in NumberHandles.
@retval EFI_NOT_FOUND No FVB handle was found.
@retval EFI_OUT_OF_RESOURCES There is not enough pool memory to store the matching results.
@retval EFI_INVALID_PARAMETER NumberHandles is NULL or Buffer is NULL.
**/
EFI_STATUS
GetFvbCountAndBuffer (
OUT UINTN *NumberHandles,
OUT EFI_HANDLE **Buffer
);
/**
Allocate private data for FTW driver and initialize it.
@param[out] FtwData Pointer to the FTW device structure
@retval EFI_SUCCESS Initialize the FTW device successfully.
@retval EFI_OUT_OF_RESOURCES Allocate memory error
@retval EFI_INVALID_PARAMETER Workspace or Spare block does not exist
**/
EFI_STATUS
InitFtwDevice (
OUT EFI_FTW_DEVICE **FtwData
);
/**
Initialization for Fault Tolerant Write is done in this handler.
@param[in, out] FtwDevice Pointer to the FTW device structure
@retval EFI_SUCCESS Initialize the FTW protocol successfully.
@retval EFI_NOT_FOUND No proper FVB protocol was found.
**/
EFI_STATUS
InitFtwProtocol (
IN OUT EFI_FTW_DEVICE *FtwDevice
);
#endif
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