audk/OvmfPkg/XenPvBlkDxe/BlockIo.c

271 lines
8.8 KiB
C

/** @file
BlockIo implementation for Xen PV Block driver.
This file is implementing the interface between the actual driver in
BlockFront.c to the BlockIo protocol.
Copyright (C) 2014, Citrix Ltd.
SPDX-License-Identifier: BSD-2-Clause-Patent
**/
#include "XenPvBlkDxe.h"
#include "BlockFront.h"
///
/// Block I/O Media structure
///
GLOBAL_REMOVE_IF_UNREFERENCED
EFI_BLOCK_IO_MEDIA gXenPvBlkDxeBlockIoMedia = {
0, // MediaId
FALSE, // RemovableMedia
FALSE, // MediaPresent
FALSE, // LogicalPartition
TRUE, // ReadOnly
FALSE, // WriteCaching
512, // BlockSize
512, // IoAlign, BlockFront does not support less than 512 bits-aligned.
0, // LastBlock
0, // LowestAlignedLba
0, // LogicalBlocksPerPhysicalBlock
0 // OptimalTransferLengthGranularity
};
///
/// Block I/O Protocol instance
///
GLOBAL_REMOVE_IF_UNREFERENCED
EFI_BLOCK_IO_PROTOCOL gXenPvBlkDxeBlockIo = {
EFI_BLOCK_IO_PROTOCOL_REVISION3, // Revision
&gXenPvBlkDxeBlockIoMedia, // Media
XenPvBlkDxeBlockIoReset, // Reset
XenPvBlkDxeBlockIoReadBlocks, // ReadBlocks
XenPvBlkDxeBlockIoWriteBlocks, // WriteBlocks
XenPvBlkDxeBlockIoFlushBlocks // FlushBlocks
};
/**
Read/Write BufferSize bytes from Lba into Buffer.
This function is common to XenPvBlkDxeBlockIoReadBlocks and
XenPvBlkDxeBlockIoWriteBlocks.
@param This Indicates a pointer to the calling context.
@param MediaId Id of the media, changes every time the media is replaced.
@param Lba The starting Logical Block Address to read from/write to.
@param BufferSize Size of Buffer, must be a multiple of device block size.
@param Buffer A pointer to the destination/source buffer for the data.
@param IsWrite Indicate if the operation is write or read.
@return See description of XenPvBlkDxeBlockIoReadBlocks and
XenPvBlkDxeBlockIoWriteBlocks.
**/
STATIC
EFI_STATUS
XenPvBlkDxeBlockIoReadWriteBlocks (
IN EFI_BLOCK_IO_PROTOCOL *This,
IN UINT32 MediaId,
IN EFI_LBA Lba,
IN UINTN BufferSize,
IN OUT VOID *Buffer,
IN BOOLEAN IsWrite
)
{
XEN_BLOCK_FRONT_IO IoData;
EFI_BLOCK_IO_MEDIA *Media = This->Media;
UINTN Sector;
EFI_STATUS Status;
if (Buffer == NULL) {
return EFI_INVALID_PARAMETER;
}
if (BufferSize == 0) {
return EFI_SUCCESS;
}
if (BufferSize % Media->BlockSize != 0) {
DEBUG ((DEBUG_ERROR, "XenPvBlkDxe: Bad buffer size: 0x%Lx\n",
(UINT64)BufferSize));
return EFI_BAD_BUFFER_SIZE;
}
if (Lba > Media->LastBlock ||
(BufferSize / Media->BlockSize) - 1 > Media->LastBlock - Lba) {
DEBUG ((DEBUG_ERROR,
"XenPvBlkDxe: %a with invalid LBA: 0x%Lx, size: 0x%Lx\n",
IsWrite ? "Write" : "Read", Lba, (UINT64)BufferSize));
return EFI_INVALID_PARAMETER;
}
if (IsWrite && Media->ReadOnly) {
return EFI_WRITE_PROTECTED;
}
if ((Media->IoAlign > 1) && (UINTN)Buffer & (Media->IoAlign - 1)) {
//
// Grub2 does not appear to respect IoAlign of 512, so reallocate the
// buffer here.
//
VOID *NewBuffer;
//
// Try again with a properly aligned buffer.
//
NewBuffer = AllocateAlignedPages((BufferSize + EFI_PAGE_SIZE) / EFI_PAGE_SIZE,
Media->IoAlign);
if (!IsWrite) {
Status = XenPvBlkDxeBlockIoReadBlocks (This, MediaId,
Lba, BufferSize, NewBuffer);
CopyMem (Buffer, NewBuffer, BufferSize);
} else {
CopyMem (NewBuffer, Buffer, BufferSize);
Status = XenPvBlkDxeBlockIoWriteBlocks (This, MediaId,
Lba, BufferSize, NewBuffer);
}
FreeAlignedPages (NewBuffer, (BufferSize + EFI_PAGE_SIZE) / EFI_PAGE_SIZE);
return Status;
}
IoData.Dev = XEN_BLOCK_FRONT_FROM_BLOCK_IO (This);
Sector = (UINTN)MultU64x32 (Lba, Media->BlockSize / 512);
while (BufferSize > 0) {
if (((UINTN)Buffer & EFI_PAGE_MASK) == 0) {
IoData.Size = MIN (BLKIF_MAX_SEGMENTS_PER_REQUEST * EFI_PAGE_SIZE,
BufferSize);
} else {
IoData.Size = MIN ((BLKIF_MAX_SEGMENTS_PER_REQUEST - 1) * EFI_PAGE_SIZE,
BufferSize);
}
IoData.Buffer = Buffer;
IoData.Sector = Sector;
BufferSize -= IoData.Size;
Buffer = (VOID*) ((UINTN) Buffer + IoData.Size);
Sector += IoData.Size / 512;
Status = XenPvBlockIo (&IoData, IsWrite);
if (EFI_ERROR (Status)) {
DEBUG ((DEBUG_ERROR, "XenPvBlkDxe: Error during %a operation.\n",
IsWrite ? "write" : "read"));
return Status;
}
}
return EFI_SUCCESS;
}
/**
Read BufferSize bytes from Lba into Buffer.
@param This Indicates a pointer to the calling context.
@param MediaId Id of the media, changes every time the media is replaced.
@param Lba The starting Logical Block Address to read from
@param BufferSize Size of Buffer, must be a multiple of device block size.
@param 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 match 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
XenPvBlkDxeBlockIoReadBlocks (
IN EFI_BLOCK_IO_PROTOCOL *This,
IN UINT32 MediaId,
IN EFI_LBA Lba,
IN UINTN BufferSize,
OUT VOID *Buffer
)
{
return XenPvBlkDxeBlockIoReadWriteBlocks (This,
MediaId, Lba, BufferSize, Buffer, FALSE);
}
/**
Write BufferSize bytes from Lba into Buffer.
@param This Indicates a pointer to the calling context.
@param MediaId The media ID that the write request is for.
@param Lba The starting logical block address to be written. The caller is
responsible for writing to only legitimate locations.
@param BufferSize Size of Buffer, must be a multiple of device block size.
@param 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_CHANGED The MediaId does not match 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
XenPvBlkDxeBlockIoWriteBlocks (
IN EFI_BLOCK_IO_PROTOCOL *This,
IN UINT32 MediaId,
IN EFI_LBA Lba,
IN UINTN BufferSize,
IN VOID *Buffer
)
{
return XenPvBlkDxeBlockIoReadWriteBlocks (This,
MediaId, Lba, BufferSize, Buffer, TRUE);
}
/**
Flush the Block Device.
@param 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 writing back the data
@retval EFI_NO_MEDIA There is no media in the device.
**/
EFI_STATUS
EFIAPI
XenPvBlkDxeBlockIoFlushBlocks (
IN EFI_BLOCK_IO_PROTOCOL *This
)
{
XenPvBlockSync (XEN_BLOCK_FRONT_FROM_BLOCK_IO (This));
return EFI_SUCCESS;
}
/**
Reset the block device hardware.
@param[in] This Indicates a pointer to the calling context.
@param[in] ExtendedVerification Not used.
@retval EFI_SUCCESS The device was reset.
**/
EFI_STATUS
EFIAPI
XenPvBlkDxeBlockIoReset (
IN EFI_BLOCK_IO_PROTOCOL *This,
IN BOOLEAN ExtendedVerification
)
{
//
// Since the initialization of the devices is done, then the device is
// working correctly.
//
return EFI_SUCCESS;
}