MdeModulePkg/Universal/Disk/RamDiskDxe/RamDiskBlockIo.c - edk2 - Git at Google

 /** @file
   Produce EFI_BLOCK_IO_PROTOCOL on a RAM disk device.

   Copyright (c) 2016, 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.

 **/

 #include "RamDiskImpl.h"

 //
 // The EFI_BLOCK_IO_PROTOCOL instances that is installed onto the handle
 // for newly registered RAM disks
 //
 EFI_BLOCK_IO_PROTOCOL  mRamDiskBlockIoTemplate = {
   EFI_BLOCK_IO_PROTOCOL_REVISION,
   (EFI_BLOCK_IO_MEDIA *) 0,
   RamDiskBlkIoReset,
   RamDiskBlkIoReadBlocks,
   RamDiskBlkIoWriteBlocks,
   RamDiskBlkIoFlushBlocks
 };

 //
 // The EFI_BLOCK_IO_PROTOCOL2 instances that is installed onto the handle
 // for newly registered RAM disks
 //
 EFI_BLOCK_IO2_PROTOCOL  mRamDiskBlockIo2Template = {
   (EFI_BLOCK_IO_MEDIA *) 0,
   RamDiskBlkIo2Reset,
   RamDiskBlkIo2ReadBlocksEx,
   RamDiskBlkIo2WriteBlocksEx,
   RamDiskBlkIo2FlushBlocksEx
 };


 /**
   Initialize the BlockIO & BlockIO2 protocol of a RAM disk device.

   @param[in] PrivateData     Points to RAM disk private data.

 **/
 VOID
 RamDiskInitBlockIo (
   IN     RAM_DISK_PRIVATE_DATA    *PrivateData
   )
 {
   EFI_BLOCK_IO_PROTOCOL           *BlockIo;
   EFI_BLOCK_IO2_PROTOCOL          *BlockIo2;
   EFI_BLOCK_IO_MEDIA              *Media;

   BlockIo  = &PrivateData->BlockIo;
   BlockIo2 = &PrivateData->BlockIo2;
   Media    = &PrivateData->Media;

   CopyMem (BlockIo, &mRamDiskBlockIoTemplate, sizeof (EFI_BLOCK_IO_PROTOCOL));
   CopyMem (BlockIo2, &mRamDiskBlockIo2Template, sizeof (EFI_BLOCK_IO2_PROTOCOL));

   BlockIo->Media          = Media;
   BlockIo2->Media         = Media;
   Media->RemovableMedia   = FALSE;
   Media->MediaPresent     = TRUE;
   Media->LogicalPartition = FALSE;
   Media->ReadOnly         = FALSE;
   Media->WriteCaching     = FALSE;
   Media->BlockSize        = RAM_DISK_BLOCK_SIZE;
   Media->LastBlock        = DivU64x32 (
                               PrivateData->Size + RAM_DISK_BLOCK_SIZE - 1,
                               RAM_DISK_BLOCK_SIZE
                               ) - 1;
 }


 /**
   Reset the Block Device.

   @param  This                 Indicates a pointer to the calling context.
   @param  ExtendedVerification Driver may perform diagnostics on reset.

   @retval EFI_SUCCESS          The device was reset.
   @retval EFI_DEVICE_ERROR     The device is not functioning properly and could
                                not be reset.

 **/
 EFI_STATUS
 EFIAPI
 RamDiskBlkIoReset (
   IN EFI_BLOCK_IO_PROTOCOL        *This,
   IN BOOLEAN                      ExtendedVerification
   )
 {
   return EFI_SUCCESS;
 }


 /**
   Read BufferSize bytes from Lba into Buffer.

   @param[in]  This           Indicates a pointer to the calling context.
   @param[in]  MediaId        Id of the media, changes every time the media is
                              replaced.
   @param[in]  Lba            The starting Logical Block Address to read from.
   @param[in]  BufferSize     Size of Buffer, must be a multiple of device block
                              size.
   @param[out] Buffer         A pointer to the destination buffer for the data.
                              The caller is responsible for either having
                              implicit or explicit ownership of the buffer.

   @retval EFI_SUCCESS             The data was read correctly from the device.
   @retval EFI_DEVICE_ERROR        The device reported an error while performing
                                   the read.
   @retval EFI_NO_MEDIA            There is no media in the device.
   @retval EFI_MEDIA_CHANGED       The MediaId does not matched the current
                                   device.
   @retval EFI_BAD_BUFFER_SIZE     The Buffer was not a multiple of the block
                                   size of the device.
   @retval EFI_INVALID_PARAMETER   The read request contains LBAs that are not
                                   valid, or the buffer is not on proper alignment.

 **/
 EFI_STATUS
 EFIAPI
 RamDiskBlkIoReadBlocks (
   IN EFI_BLOCK_IO_PROTOCOL        *This,
   IN UINT32                       MediaId,
   IN EFI_LBA                      Lba,
   IN UINTN                        BufferSize,
   OUT VOID                        *Buffer
   )
 {
   RAM_DISK_PRIVATE_DATA           *PrivateData;
   UINTN                           NumberOfBlocks;

   if (Buffer == NULL) {
     return EFI_INVALID_PARAMETER;
   }

   if (BufferSize == 0) {
     return EFI_SUCCESS;
   }

   PrivateData = RAM_DISK_PRIVATE_FROM_BLKIO (This);

   if (MediaId != PrivateData->Media.MediaId) {
     return EFI_MEDIA_CHANGED;
   }

   if ((BufferSize % PrivateData->Media.BlockSize) != 0) {
     return EFI_BAD_BUFFER_SIZE;
   }

   if (Lba > PrivateData->Media.LastBlock) {
     return EFI_INVALID_PARAMETER;
   }

   NumberOfBlocks = BufferSize / PrivateData->Media.BlockSize;
   if ((Lba + NumberOfBlocks - 1) > PrivateData->Media.LastBlock) {
     return EFI_INVALID_PARAMETER;
   }

   CopyMem (
     Buffer,
     (VOID *)(UINTN)(PrivateData->StartingAddr + MultU64x32 (Lba, PrivateData->Media.BlockSize)),
     BufferSize
     );

   return EFI_SUCCESS;
 }


 /**
   Write BufferSize bytes from Lba into Buffer.

   @param[in] This            Indicates a pointer to the calling context.
   @param[in] MediaId         The media ID that the write request is for.
   @param[in] Lba             The starting logical block address to be written.
                              The caller is responsible for writing to only
                              legitimate locations.
   @param[in] BufferSize      Size of Buffer, must be a multiple of device block
                              size.
   @param[in] Buffer          A pointer to the source buffer for the data.

   @retval EFI_SUCCESS             The data was written correctly to the device.
   @retval EFI_WRITE_PROTECTED     The device can not be written to.
   @retval EFI_DEVICE_ERROR        The device reported an error while performing
                                   the write.
   @retval EFI_NO_MEDIA            There is no media in the device.
   @retval EFI_MEDIA_CHNAGED       The MediaId does not matched the current
                                   device.
   @retval EFI_BAD_BUFFER_SIZE     The Buffer was not a multiple of the block
                                   size of the device.
   @retval EFI_INVALID_PARAMETER   The write request contains LBAs that are not
                                   valid, or the buffer is not on proper alignment.

 **/
 EFI_STATUS
 EFIAPI
 RamDiskBlkIoWriteBlocks (
   IN EFI_BLOCK_IO_PROTOCOL        *This,
   IN UINT32                       MediaId,
   IN EFI_LBA                      Lba,
   IN UINTN                        BufferSize,
   IN VOID                         *Buffer
   )
 {
   RAM_DISK_PRIVATE_DATA           *PrivateData;
   UINTN                           NumberOfBlocks;

   if (Buffer == NULL) {
     return EFI_INVALID_PARAMETER;
   }

   if (BufferSize == 0) {
     return EFI_SUCCESS;
   }

   PrivateData = RAM_DISK_PRIVATE_FROM_BLKIO (This);

   if (MediaId != PrivateData->Media.MediaId) {
     return EFI_MEDIA_CHANGED;
   }

   if (TRUE == PrivateData->Media.ReadOnly) {
     return EFI_WRITE_PROTECTED;
   }

   if ((BufferSize % PrivateData->Media.BlockSize) != 0) {
     return EFI_BAD_BUFFER_SIZE;
   }

   if (Lba > PrivateData->Media.LastBlock) {
     return EFI_INVALID_PARAMETER;
   }

   NumberOfBlocks = BufferSize / PrivateData->Media.BlockSize;
   if ((Lba + NumberOfBlocks - 1) > PrivateData->Media.LastBlock) {
     return EFI_INVALID_PARAMETER;
   }

   CopyMem (
     (VOID *)(UINTN)(PrivateData->StartingAddr + MultU64x32 (Lba, PrivateData->Media.BlockSize)),
     Buffer,
     BufferSize
     );

   return EFI_SUCCESS;
 }


 /**
   Flush the Block Device.

   @param[in] This            Indicates a pointer to the calling context.

   @retval EFI_SUCCESS             All outstanding data was written to the device.
   @retval EFI_DEVICE_ERROR        The device reported an error while writting
                                   back the data
   @retval EFI_NO_MEDIA            There is no media in the device.

 **/
 EFI_STATUS
 EFIAPI
 RamDiskBlkIoFlushBlocks (
   IN EFI_BLOCK_IO_PROTOCOL        *This
   )
 {
   return EFI_SUCCESS;
 }


 /**
   Resets the block device hardware.

   @param[in] This                 The pointer of EFI_BLOCK_IO2_PROTOCOL.
   @param[in] ExtendedVerification The flag about if extend verificate.

   @retval EFI_SUCCESS             The device was reset.
   @retval EFI_DEVICE_ERROR        The block device is not functioning correctly
                                   and could not be reset.

 **/
 EFI_STATUS
 EFIAPI
 RamDiskBlkIo2Reset (
   IN EFI_BLOCK_IO2_PROTOCOL       *This,
   IN BOOLEAN                      ExtendedVerification
   )
 {
   return EFI_SUCCESS;
 }


 /**
   Reads the requested number of blocks from the device.

   @param[in]      This            Indicates a pointer to the calling context.
   @param[in]      MediaId         The media ID that the read request is for.
   @param[in]      Lba             The starting logical block address to read
                                   from on the device.
   @param[in, out] Token           A pointer to the token associated with the
                                   transaction.
   @param[in]      BufferSize      The size of the Buffer in bytes. This must be
                                   a multiple of the intrinsic block size of the
                                   device.
   @param[out]     Buffer          A pointer to the destination buffer for the
                                   data. The caller is responsible for either
                                   having implicit or explicit ownership of the
                                   buffer.

   @retval EFI_SUCCESS             The read request was queued if Token->Event
                                   is not NULL. The data was read correctly from
                                   the device if the Token->Event is NULL.
   @retval EFI_DEVICE_ERROR        The device reported an error while attempting
                                   to perform the read operation.
   @retval EFI_NO_MEDIA            There is no media in the device.
   @retval EFI_MEDIA_CHANGED       The MediaId is not for the current media.
   @retval EFI_BAD_BUFFER_SIZE     The BufferSize parameter is not a multiple of
                                   the intrinsic block size of the device.
   @retval EFI_INVALID_PARAMETER   The read request contains LBAs that are not
                                   valid, or the buffer is not on proper
                                   alignment.
   @retval EFI_OUT_OF_RESOURCES    The request could not be completed due to a
                                   lack of resources.

 **/
 EFI_STATUS
 EFIAPI
 RamDiskBlkIo2ReadBlocksEx (
   IN     EFI_BLOCK_IO2_PROTOCOL   *This,
   IN     UINT32                   MediaId,
   IN     EFI_LBA                  Lba,
   IN OUT EFI_BLOCK_IO2_TOKEN      *Token,
   IN     UINTN                    BufferSize,
      OUT VOID                     *Buffer
   )
 {
   RAM_DISK_PRIVATE_DATA           *PrivateData;
   EFI_STATUS                      Status;

   PrivateData = RAM_DISK_PRIVATE_FROM_BLKIO2 (This);

   Status = RamDiskBlkIoReadBlocks (
               &PrivateData->BlockIo,
               MediaId,
               Lba,
               BufferSize,
               Buffer
               );
   if (EFI_ERROR (Status)) {
     return Status;
   }

   //
   // If caller's event is given, signal it after the memory read completes.
   //
   if ((Token != NULL) && (Token->Event != NULL)) {
     Token->TransactionStatus = EFI_SUCCESS;
     gBS->SignalEvent (Token->Event);
   }

   return EFI_SUCCESS;
 }


 /**
   Writes a specified number of blocks to the device.

   @param[in]      This            Indicates a pointer to the calling context.
   @param[in]      MediaId         The media ID that the write request is for.
   @param[in]      Lba             The starting logical block address to be
                                   written. The caller is responsible for
                                   writing to only legitimate locations.
   @param[in, out] Token           A pointer to the token associated with the
                                   transaction.
   @param[in]      BufferSize      The size in bytes of Buffer. This must be a
                                   multiple of the intrinsic block size of the
                                   device.
   @param[in]      Buffer          A pointer to the source buffer for the data.

   @retval EFI_SUCCESS             The write request was queued if Event is not
                                   NULL. The data was written correctly to the
                                   device if the Event is NULL.
   @retval EFI_WRITE_PROTECTED     The device cannot be written to.
   @retval EFI_NO_MEDIA            There is no media in the device.
   @retval EFI_MEDIA_CHANGED       The MediaId is not for the current media.
   @retval EFI_DEVICE_ERROR        The device reported an error while attempting
                                   to perform the write operation.
   @retval EFI_BAD_BUFFER_SIZE     The BufferSize parameter is not a multiple of
                                   the intrinsic block size of the device.
   @retval EFI_INVALID_PARAMETER   The write request contains LBAs that are not
                                   valid, or the buffer is not on proper
                                   alignment.
   @retval EFI_OUT_OF_RESOURCES    The request could not be completed due to a
                                   lack of resources.

 **/
 EFI_STATUS
 EFIAPI
 RamDiskBlkIo2WriteBlocksEx (
   IN     EFI_BLOCK_IO2_PROTOCOL   *This,
   IN     UINT32                   MediaId,
   IN     EFI_LBA                  Lba,
   IN OUT EFI_BLOCK_IO2_TOKEN      *Token,
   IN     UINTN                    BufferSize,
   IN     VOID                     *Buffer
   )
 {
   RAM_DISK_PRIVATE_DATA           *PrivateData;
   EFI_STATUS                      Status;

   PrivateData = RAM_DISK_PRIVATE_FROM_BLKIO2 (This);

   Status = RamDiskBlkIoWriteBlocks (
               &PrivateData->BlockIo,
               MediaId,
               Lba,
               BufferSize,
               Buffer
               );
   if (EFI_ERROR (Status)) {
     return Status;
   }

   //
   // If caller's event is given, signal it after the memory write completes.
   //
   if ((Token != NULL) && (Token->Event != NULL)) {
     Token->TransactionStatus = EFI_SUCCESS;
     gBS->SignalEvent (Token->Event);
   }

   return EFI_SUCCESS;
 }


 /**
   Flushes all modified data to a physical block device.

   @param[in]      This            Indicates a pointer to the calling context.
   @param[in, out] Token           A pointer to the token associated with the
                                   transaction.

   @retval EFI_SUCCESS             The flush request was queued if Event is not
                                   NULL. All outstanding data was written
                                   correctly to the device if the Event is NULL.
   @retval EFI_DEVICE_ERROR        The device reported an error while attempting
                                   to write data.
   @retval EFI_WRITE_PROTECTED     The device cannot be written to.
   @retval EFI_NO_MEDIA            There is no media in the device.
   @retval EFI_MEDIA_CHANGED       The MediaId is not for the current media.
   @retval EFI_OUT_OF_RESOURCES    The request could not be completed due to a
                                   lack of resources.

 **/
 EFI_STATUS
 EFIAPI
 RamDiskBlkIo2FlushBlocksEx (
   IN     EFI_BLOCK_IO2_PROTOCOL   *This,
   IN OUT EFI_BLOCK_IO2_TOKEN      *Token
   )
 {
   RAM_DISK_PRIVATE_DATA           *PrivateData;

   PrivateData = RAM_DISK_PRIVATE_FROM_BLKIO2 (This);

   if (TRUE == PrivateData->Media.ReadOnly) {
     return EFI_WRITE_PROTECTED;
   }

   //
   // If caller's event is given, signal it directly.
   //
   if ((Token != NULL) && (Token->Event != NULL)) {
     Token->TransactionStatus = EFI_SUCCESS;
     gBS->SignalEvent (Token->Event);
   }

   return EFI_SUCCESS;
 }
	/** @file
	Produce EFI_BLOCK_IO_PROTOCOL on a RAM disk device.

	Copyright (c) 2016, 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.

	**/

	#include "RamDiskImpl.h"

	//
	// The EFI_BLOCK_IO_PROTOCOL instances that is installed onto the handle
	// for newly registered RAM disks
	//
	EFI_BLOCK_IO_PROTOCOL mRamDiskBlockIoTemplate = {
	EFI_BLOCK_IO_PROTOCOL_REVISION,
	(EFI_BLOCK_IO_MEDIA *) 0,
	RamDiskBlkIoReset,
	RamDiskBlkIoReadBlocks,
	RamDiskBlkIoWriteBlocks,
	RamDiskBlkIoFlushBlocks
	};

	//
	// The EFI_BLOCK_IO_PROTOCOL2 instances that is installed onto the handle
	// for newly registered RAM disks
	//
	EFI_BLOCK_IO2_PROTOCOL mRamDiskBlockIo2Template = {
	(EFI_BLOCK_IO_MEDIA *) 0,
	RamDiskBlkIo2Reset,
	RamDiskBlkIo2ReadBlocksEx,
	RamDiskBlkIo2WriteBlocksEx,
	RamDiskBlkIo2FlushBlocksEx
	};


	/**
	Initialize the BlockIO & BlockIO2 protocol of a RAM disk device.

	@param[in] PrivateData Points to RAM disk private data.

	**/
	VOID
	RamDiskInitBlockIo (
	IN RAM_DISK_PRIVATE_DATA *PrivateData
	)
	{
	EFI_BLOCK_IO_PROTOCOL *BlockIo;
	EFI_BLOCK_IO2_PROTOCOL *BlockIo2;
	EFI_BLOCK_IO_MEDIA *Media;

	BlockIo = &PrivateData->BlockIo;
	BlockIo2 = &PrivateData->BlockIo2;
	Media = &PrivateData->Media;

	CopyMem (BlockIo, &mRamDiskBlockIoTemplate, sizeof (EFI_BLOCK_IO_PROTOCOL));
	CopyMem (BlockIo2, &mRamDiskBlockIo2Template, sizeof (EFI_BLOCK_IO2_PROTOCOL));

	BlockIo->Media = Media;
	BlockIo2->Media = Media;
	Media->RemovableMedia = FALSE;
	Media->MediaPresent = TRUE;
	Media->LogicalPartition = FALSE;
	Media->ReadOnly = FALSE;
	Media->WriteCaching = FALSE;
	Media->BlockSize = RAM_DISK_BLOCK_SIZE;
	Media->LastBlock = DivU64x32 (
	PrivateData->Size + RAM_DISK_BLOCK_SIZE - 1,
	RAM_DISK_BLOCK_SIZE
	) - 1;
	}


	/**
	Reset the Block Device.

	@param This Indicates a pointer to the calling context.
	@param ExtendedVerification Driver may perform diagnostics on reset.

	@retval EFI_SUCCESS The device was reset.
	@retval EFI_DEVICE_ERROR The device is not functioning properly and could
	not be reset.

	**/
	EFI_STATUS
	EFIAPI
	RamDiskBlkIoReset (
	IN EFI_BLOCK_IO_PROTOCOL *This,
	IN BOOLEAN ExtendedVerification
	)
	{
	return EFI_SUCCESS;
	}


	/**
	Read BufferSize bytes from Lba into Buffer.

	@param[in] This Indicates a pointer to the calling context.
	@param[in] MediaId Id of the media, changes every time the media is
	replaced.
	@param[in] Lba The starting Logical Block Address to read from.
	@param[in] BufferSize Size of Buffer, must be a multiple of device block
	size.
	@param[out] Buffer A pointer to the destination buffer for the data.
	The caller is responsible for either having
	implicit or explicit ownership of the buffer.

	@retval EFI_SUCCESS The data was read correctly from the device.
	@retval EFI_DEVICE_ERROR The device reported an error while performing
	the read.
	@retval EFI_NO_MEDIA There is no media in the device.
	@retval EFI_MEDIA_CHANGED The MediaId does not matched the current
	device.
	@retval EFI_BAD_BUFFER_SIZE The Buffer was not a multiple of the block
	size of the device.
	@retval EFI_INVALID_PARAMETER The read request contains LBAs that are not
	valid, or the buffer is not on proper alignment.

	**/
	EFI_STATUS
	EFIAPI
	RamDiskBlkIoReadBlocks (
	IN EFI_BLOCK_IO_PROTOCOL *This,
	IN UINT32 MediaId,
	IN EFI_LBA Lba,
	IN UINTN BufferSize,
	OUT VOID *Buffer
	)
	{
	RAM_DISK_PRIVATE_DATA *PrivateData;
	UINTN NumberOfBlocks;

	if (Buffer == NULL) {
	return EFI_INVALID_PARAMETER;
	}

	if (BufferSize == 0) {
	return EFI_SUCCESS;
	}

	PrivateData = RAM_DISK_PRIVATE_FROM_BLKIO (This);

	if (MediaId != PrivateData->Media.MediaId) {
	return EFI_MEDIA_CHANGED;
	}

	if ((BufferSize % PrivateData->Media.BlockSize) != 0) {
	return EFI_BAD_BUFFER_SIZE;
	}

	if (Lba > PrivateData->Media.LastBlock) {
	return EFI_INVALID_PARAMETER;
	}

	NumberOfBlocks = BufferSize / PrivateData->Media.BlockSize;
	if ((Lba + NumberOfBlocks - 1) > PrivateData->Media.LastBlock) {
	return EFI_INVALID_PARAMETER;
	}

	CopyMem (
	Buffer,
	(VOID *)(UINTN)(PrivateData->StartingAddr + MultU64x32 (Lba, PrivateData->Media.BlockSize)),
	BufferSize
	);

	return EFI_SUCCESS;
	}


	/**
	Write BufferSize bytes from Lba into Buffer.

	@param[in] This Indicates a pointer to the calling context.
	@param[in] MediaId The media ID that the write request is for.
	@param[in] Lba The starting logical block address to be written.
	The caller is responsible for writing to only
	legitimate locations.
	@param[in] BufferSize Size of Buffer, must be a multiple of device block
	size.
	@param[in] Buffer A pointer to the source buffer for the data.

	@retval EFI_SUCCESS The data was written correctly to the device.
	@retval EFI_WRITE_PROTECTED The device can not be written to.
	@retval EFI_DEVICE_ERROR The device reported an error while performing
	the write.
	@retval EFI_NO_MEDIA There is no media in the device.
	@retval EFI_MEDIA_CHNAGED The MediaId does not matched the current
	device.
	@retval EFI_BAD_BUFFER_SIZE The Buffer was not a multiple of the block
	size of the device.
	@retval EFI_INVALID_PARAMETER The write request contains LBAs that are not
	valid, or the buffer is not on proper alignment.

	**/
	EFI_STATUS
	EFIAPI
	RamDiskBlkIoWriteBlocks (
	IN EFI_BLOCK_IO_PROTOCOL *This,
	IN UINT32 MediaId,
	IN EFI_LBA Lba,
	IN UINTN BufferSize,
	IN VOID *Buffer
	)
	{
	RAM_DISK_PRIVATE_DATA *PrivateData;
	UINTN NumberOfBlocks;

	if (Buffer == NULL) {
	return EFI_INVALID_PARAMETER;
	}

	if (BufferSize == 0) {
	return EFI_SUCCESS;
	}

	PrivateData = RAM_DISK_PRIVATE_FROM_BLKIO (This);

	if (MediaId != PrivateData->Media.MediaId) {
	return EFI_MEDIA_CHANGED;
	}

	if (TRUE == PrivateData->Media.ReadOnly) {
	return EFI_WRITE_PROTECTED;
	}

	if ((BufferSize % PrivateData->Media.BlockSize) != 0) {
	return EFI_BAD_BUFFER_SIZE;
	}

	if (Lba > PrivateData->Media.LastBlock) {
	return EFI_INVALID_PARAMETER;
	}

	NumberOfBlocks = BufferSize / PrivateData->Media.BlockSize;
	if ((Lba + NumberOfBlocks - 1) > PrivateData->Media.LastBlock) {
	return EFI_INVALID_PARAMETER;
	}

	CopyMem (
	(VOID *)(UINTN)(PrivateData->StartingAddr + MultU64x32 (Lba, PrivateData->Media.BlockSize)),
	Buffer,
	BufferSize
	);

	return EFI_SUCCESS;
	}


	/**
	Flush the Block Device.

	@param[in] This Indicates a pointer to the calling context.

	@retval EFI_SUCCESS All outstanding data was written to the device.
	@retval EFI_DEVICE_ERROR The device reported an error while writting
	back the data
	@retval EFI_NO_MEDIA There is no media in the device.

	**/
	EFI_STATUS
	EFIAPI
	RamDiskBlkIoFlushBlocks (
	IN EFI_BLOCK_IO_PROTOCOL *This
	)
	{
	return EFI_SUCCESS;
	}


	/**
	Resets the block device hardware.

	@param[in] This The pointer of EFI_BLOCK_IO2_PROTOCOL.
	@param[in] ExtendedVerification The flag about if extend verificate.

	@retval EFI_SUCCESS The device was reset.
	@retval EFI_DEVICE_ERROR The block device is not functioning correctly
	and could not be reset.

	**/
	EFI_STATUS
	EFIAPI
	RamDiskBlkIo2Reset (
	IN EFI_BLOCK_IO2_PROTOCOL *This,
	IN BOOLEAN ExtendedVerification
	)
	{
	return EFI_SUCCESS;
	}


	/**
	Reads the requested number of blocks from the device.

	@param[in] This Indicates a pointer to the calling context.
	@param[in] MediaId The media ID that the read request is for.
	@param[in] Lba The starting logical block address to read
	from on the device.
	@param[in, out] Token A pointer to the token associated with the
	transaction.
	@param[in] BufferSize The size of the Buffer in bytes. This must be
	a multiple of the intrinsic block size of the
	device.
	@param[out] Buffer A pointer to the destination buffer for the
	data. The caller is responsible for either
	having implicit or explicit ownership of the
	buffer.

	@retval EFI_SUCCESS The read request was queued if Token->Event
	is not NULL. The data was read correctly from
	the device if the Token->Event is NULL.
	@retval EFI_DEVICE_ERROR The device reported an error while attempting
	to perform the read operation.
	@retval EFI_NO_MEDIA There is no media in the device.
	@retval EFI_MEDIA_CHANGED The MediaId is not for the current media.
	@retval EFI_BAD_BUFFER_SIZE The BufferSize parameter is not a multiple of
	the intrinsic block size of the device.
	@retval EFI_INVALID_PARAMETER The read request contains LBAs that are not
	valid, or the buffer is not on proper
	alignment.
	@retval EFI_OUT_OF_RESOURCES The request could not be completed due to a
	lack of resources.

	**/
	EFI_STATUS
	EFIAPI
	RamDiskBlkIo2ReadBlocksEx (
	IN EFI_BLOCK_IO2_PROTOCOL *This,
	IN UINT32 MediaId,
	IN EFI_LBA Lba,
	IN OUT EFI_BLOCK_IO2_TOKEN *Token,
	IN UINTN BufferSize,
	OUT VOID *Buffer
	)
	{
	RAM_DISK_PRIVATE_DATA *PrivateData;
	EFI_STATUS Status;

	PrivateData = RAM_DISK_PRIVATE_FROM_BLKIO2 (This);

	Status = RamDiskBlkIoReadBlocks (
	&PrivateData->BlockIo,
	MediaId,
	Lba,
	BufferSize,
	Buffer
	);
	if (EFI_ERROR (Status)) {
	return Status;
	}

	//
	// If caller's event is given, signal it after the memory read completes.
	//
	if ((Token != NULL) && (Token->Event != NULL)) {
	Token->TransactionStatus = EFI_SUCCESS;
	gBS->SignalEvent (Token->Event);
	}

	return EFI_SUCCESS;
	}


	/**
	Writes a specified number of blocks to the device.

	@param[in] This Indicates a pointer to the calling context.
	@param[in] MediaId The media ID that the write request is for.
	@param[in] Lba The starting logical block address to be
	written. The caller is responsible for
	writing to only legitimate locations.
	@param[in, out] Token A pointer to the token associated with the
	transaction.
	@param[in] BufferSize The size in bytes of Buffer. This must be a
	multiple of the intrinsic block size of the
	device.
	@param[in] Buffer A pointer to the source buffer for the data.

	@retval EFI_SUCCESS The write request was queued if Event is not
	NULL. The data was written correctly to the
	device if the Event is NULL.
	@retval EFI_WRITE_PROTECTED The device cannot be written to.
	@retval EFI_NO_MEDIA There is no media in the device.
	@retval EFI_MEDIA_CHANGED The MediaId is not for the current media.
	@retval EFI_DEVICE_ERROR The device reported an error while attempting
	to perform the write operation.
	@retval EFI_BAD_BUFFER_SIZE The BufferSize parameter is not a multiple of
	the intrinsic block size of the device.
	@retval EFI_INVALID_PARAMETER The write request contains LBAs that are not
	valid, or the buffer is not on proper
	alignment.
	@retval EFI_OUT_OF_RESOURCES The request could not be completed due to a
	lack of resources.

	**/
	EFI_STATUS
	EFIAPI
	RamDiskBlkIo2WriteBlocksEx (
	IN EFI_BLOCK_IO2_PROTOCOL *This,
	IN UINT32 MediaId,
	IN EFI_LBA Lba,
	IN OUT EFI_BLOCK_IO2_TOKEN *Token,
	IN UINTN BufferSize,
	IN VOID *Buffer
	)
	{
	RAM_DISK_PRIVATE_DATA *PrivateData;
	EFI_STATUS Status;

	PrivateData = RAM_DISK_PRIVATE_FROM_BLKIO2 (This);

	Status = RamDiskBlkIoWriteBlocks (
	&PrivateData->BlockIo,
	MediaId,
	Lba,
	BufferSize,
	Buffer
	);
	if (EFI_ERROR (Status)) {
	return Status;
	}

	//
	// If caller's event is given, signal it after the memory write completes.
	//
	if ((Token != NULL) && (Token->Event != NULL)) {
	Token->TransactionStatus = EFI_SUCCESS;
	gBS->SignalEvent (Token->Event);
	}

	return EFI_SUCCESS;
	}


	/**
	Flushes all modified data to a physical block device.

	@param[in] This Indicates a pointer to the calling context.
	@param[in, out] Token A pointer to the token associated with the
	transaction.

	@retval EFI_SUCCESS The flush request was queued if Event is not
	NULL. All outstanding data was written
	correctly to the device if the Event is NULL.
	@retval EFI_DEVICE_ERROR The device reported an error while attempting
	to write data.
	@retval EFI_WRITE_PROTECTED The device cannot be written to.
	@retval EFI_NO_MEDIA There is no media in the device.
	@retval EFI_MEDIA_CHANGED The MediaId is not for the current media.
	@retval EFI_OUT_OF_RESOURCES The request could not be completed due to a
	lack of resources.

	**/
	EFI_STATUS
	EFIAPI
	RamDiskBlkIo2FlushBlocksEx (
	IN EFI_BLOCK_IO2_PROTOCOL *This,
	IN OUT EFI_BLOCK_IO2_TOKEN *Token
	)
	{
	RAM_DISK_PRIVATE_DATA *PrivateData;

	PrivateData = RAM_DISK_PRIVATE_FROM_BLKIO2 (This);

	if (TRUE == PrivateData->Media.ReadOnly) {
	return EFI_WRITE_PROTECTED;
	}

	//
	// If caller's event is given, signal it directly.
	//
	if ((Token != NULL) && (Token->Event != NULL)) {
	Token->TransactionStatus = EFI_SUCCESS;
	gBS->SignalEvent (Token->Event);
	}

	return EFI_SUCCESS;
	}