/** @copydoc VBOXHDDBACKEND::pfnAsyncRead */
static int parallelsAsyncRead(void *pBackendData, uint64_t uOffset, size_t cbToRead,
PVDIOCTX pIoCtx, size_t *pcbActuallyRead)
{
LogFlowFunc(("pBackendData=%#p uOffset=%llu pIoCtx=%#p cbToRead=%zu pcbActuallyRead=%#p\n",
pBackendData, uOffset, pIoCtx, cbToRead, pcbActuallyRead));
int rc = VINF_SUCCESS;
PPARALLELSIMAGE pImage = (PPARALLELSIMAGE)pBackendData;
uint64_t uSector;
uint64_t uOffsetInFile;
uint32_t iIndexInAllocationTable;
AssertPtr(pImage);
Assert(uOffset % 512 == 0);
Assert(cbToRead % 512 == 0);
if (pImage->uImageFlags & VD_IMAGE_FLAGS_FIXED)
rc = vdIfIoIntFileReadUserAsync(pImage->pIfIo, pImage->pStorage, uOffset,
pIoCtx, cbToRead);
else
{
/* Calculate offset in the real file. */
uSector = uOffset / 512;
/* One chunk in the file is always one track big. */
iIndexInAllocationTable = (uint32_t)(uSector / pImage->PCHSGeometry.cSectors);
uSector = uSector % pImage->PCHSGeometry.cSectors;
cbToRead = RT_MIN(cbToRead, (pImage->PCHSGeometry.cSectors - uSector)*512);
if (pImage->pAllocationBitmap[iIndexInAllocationTable] == 0)
{
rc = VERR_VD_BLOCK_FREE;
}
else
{
uOffsetInFile = (pImage->pAllocationBitmap[iIndexInAllocationTable] + uSector) * 512;
rc = vdIfIoIntFileReadUserAsync(pImage->pIfIo, pImage->pStorage, uOffsetInFile,
pIoCtx, cbToRead);
}
}
*pcbActuallyRead = cbToRead;
LogFlowFunc(("returns %Rrc\n", rc));
return rc;
}
/** @copydoc VBOXHDDBACKEND::pfnAsyncRead */
static int rawAsyncRead(void *pBackendData, uint64_t uOffset, size_t cbRead,
PVDIOCTX pIoCtx, size_t *pcbActuallyRead)
{
int rc = VINF_SUCCESS;
PRAWIMAGE pImage = (PRAWIMAGE)pBackendData;
rc = vdIfIoIntFileReadUserAsync(pImage->pIfIo, pImage->pStorage, uOffset,
pIoCtx, cbRead);
if (RT_SUCCESS(rc))
*pcbActuallyRead = cbRead;
return rc;
}