/** @file
  Produce EFI_BLOCK_IO_PROTOCOL on a RAM disk device.

  Copyright (c) 2016 - 2019, Intel Corporation. All rights reserved.<BR>
  SPDX-License-Identifier: BSD-2-Clause-Patent

**/

#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;
  UINT32                  Remainder;

  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;

  for (Media->BlockSize = RAM_DISK_DEFAULT_BLOCK_SIZE;
       Media->BlockSize >= 1;
       Media->BlockSize = Media->BlockSize >> 1)
  {
    Media->LastBlock = DivU64x32Remainder (PrivateData->Size, Media->BlockSize, &Remainder) - 1;
    if (Remainder == 0) {
      break;
    }
  }

  ASSERT (Media->BlockSize != 0);

  return;
}

/**
  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;

  PrivateData = RAM_DISK_PRIVATE_FROM_BLKIO (This);

  if (MediaId != PrivateData->Media.MediaId) {
    return EFI_MEDIA_CHANGED;
  }

  if (Buffer == NULL) {
    return EFI_INVALID_PARAMETER;
  }

  if (BufferSize == 0) {
    return EFI_SUCCESS;
  }

  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;

  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 (Buffer == NULL) {
    return EFI_INVALID_PARAMETER;
  }

  if (BufferSize == 0) {
    return EFI_SUCCESS;
  }

  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;
}