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diff --git a/src/VBox/Storage/VHD.cpp b/src/VBox/Storage/VHD.cpp
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+/* $Id: VHD.cpp $ */
+/** @file
+ * VHD Disk image, Core Code.
+ */
+
+/*
+ * Copyright (C) 2006-2022 Oracle and/or its affiliates.
+ *
+ * This file is part of VirtualBox base platform packages, as
+ * available from https://www.virtualbox.org.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, in version 3 of the
+ * License.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <https://www.gnu.org/licenses>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-only
+ */
+
+
+/*********************************************************************************************************************************
+* Header Files *
+*********************************************************************************************************************************/
+#define LOG_GROUP LOG_GROUP_VD_VHD
+#include <VBox/vd-plugin.h>
+#include <VBox/err.h>
+
+#include <VBox/log.h>
+#include <VBox/version.h>
+#include <iprt/asm.h>
+#include <iprt/assert.h>
+#include <iprt/mem.h>
+#include <iprt/uuid.h>
+#include <iprt/path.h>
+#include <iprt/string.h>
+#include <iprt/utf16.h>
+
+#include "VDBackends.h"
+
+#define VHD_RELATIVE_MAX_PATH 512
+#define VHD_ABSOLUTE_MAX_PATH 512
+
+#define VHD_SECTOR_SIZE 512
+#define VHD_BLOCK_SIZE (2 * _1M)
+
+/** The maximum VHD size is 2TB due to the 32bit sector numbers in the BAT.
+ * Note that this is the maximum file size including all footers and headers
+ * and not the maximum virtual disk size presented to the guest.
+ */
+#define VHD_MAX_SIZE (2 * _1T)
+/** Maximum number of 512 byte sectors for a VHD image. */
+#define VHD_MAX_SECTORS (VHD_MAX_SIZE / VHD_SECTOR_SIZE)
+
+/* This is common to all VHD disk types and is located at the end of the image */
+#pragma pack(1)
+typedef struct VHDFooter
+{
+ char Cookie[8];
+ uint32_t Features;
+ uint32_t Version;
+ uint64_t DataOffset;
+ uint32_t Timestamp;
+ uint8_t CreatorApp[4];
+ uint32_t CreatorVer;
+ uint32_t CreatorOS;
+ uint64_t OrigSize;
+ uint64_t CurSize;
+ uint16_t DiskGeometryCylinder;
+ uint8_t DiskGeometryHeads;
+ uint8_t DiskGeometrySectors;
+ uint32_t DiskType;
+ uint32_t Checksum;
+ char UniqueID[16];
+ uint8_t SavedState;
+ uint8_t Reserved[427];
+} VHDFooter;
+#pragma pack()
+
+/* this really is spelled with only one n */
+#define VHD_FOOTER_COOKIE "conectix"
+#define VHD_FOOTER_COOKIE_SIZE 8
+
+#define VHD_FOOTER_FEATURES_NOT_ENABLED 0
+#define VHD_FOOTER_FEATURES_TEMPORARY 1
+#define VHD_FOOTER_FEATURES_RESERVED 2
+
+#define VHD_FOOTER_FILE_FORMAT_VERSION 0x00010000
+#define VHD_FOOTER_DATA_OFFSET_FIXED UINT64_C(0xffffffffffffffff)
+#define VHD_FOOTER_DISK_TYPE_FIXED 2
+#define VHD_FOOTER_DISK_TYPE_DYNAMIC 3
+#define VHD_FOOTER_DISK_TYPE_DIFFERENCING 4
+
+#define VHD_MAX_LOCATOR_ENTRIES 8
+#define VHD_PLATFORM_CODE_NONE 0
+#define VHD_PLATFORM_CODE_WI2R 0x57693272
+#define VHD_PLATFORM_CODE_WI2K 0x5769326B
+#define VHD_PLATFORM_CODE_W2RU 0x57327275
+#define VHD_PLATFORM_CODE_W2KU 0x57326B75
+#define VHD_PLATFORM_CODE_MAC 0x4D163220
+#define VHD_PLATFORM_CODE_MACX 0x4D163258
+
+/* Header for expanding disk images. */
+#pragma pack(1)
+typedef struct VHDParentLocatorEntry
+{
+ uint32_t u32Code;
+ uint32_t u32DataSpace;
+ uint32_t u32DataLength;
+ uint32_t u32Reserved;
+ uint64_t u64DataOffset;
+} VHDPLE, *PVHDPLE;
+
+typedef struct VHDDynamicDiskHeader
+{
+ char Cookie[8];
+ uint64_t DataOffset;
+ uint64_t TableOffset;
+ uint32_t HeaderVersion;
+ uint32_t MaxTableEntries;
+ uint32_t BlockSize;
+ uint32_t Checksum;
+ uint8_t ParentUuid[16];
+ uint32_t ParentTimestamp;
+ uint32_t Reserved0;
+ uint16_t ParentUnicodeName[256];
+ VHDPLE ParentLocatorEntry[VHD_MAX_LOCATOR_ENTRIES];
+ uint8_t Reserved1[256];
+} VHDDynamicDiskHeader;
+#pragma pack()
+
+#define VHD_DYNAMIC_DISK_HEADER_COOKIE "cxsparse"
+#define VHD_DYNAMIC_DISK_HEADER_COOKIE_SIZE 8
+#define VHD_DYNAMIC_DISK_HEADER_VERSION 0x00010000
+
+/**
+ * Complete VHD image data structure.
+ */
+typedef struct VHDIMAGE
+{
+ /** Image file name. */
+ const char *pszFilename;
+ /** Opaque storage handle. */
+ PVDIOSTORAGE pStorage;
+
+ /** Pointer to the per-disk VD interface list. */
+ PVDINTERFACE pVDIfsDisk;
+ /** Pointer to the per-image VD interface list. */
+ PVDINTERFACE pVDIfsImage;
+ /** Error interface. */
+ PVDINTERFACEERROR pIfError;
+ /** I/O interface. */
+ PVDINTERFACEIOINT pIfIo;
+
+ /** Open flags passed by VBoxHDD layer. */
+ unsigned uOpenFlags;
+ /** Image flags defined during creation or determined during open. */
+ unsigned uImageFlags;
+ /** Total size of the image. */
+ uint64_t cbSize;
+
+ /** Physical geometry of this image. */
+ VDGEOMETRY PCHSGeometry;
+ /** Logical geometry of this image. */
+ VDGEOMETRY LCHSGeometry;
+
+ /** Image UUID. */
+ RTUUID ImageUuid;
+ /** Parent image UUID. */
+ RTUUID ParentUuid;
+
+ /** Parent's time stamp at the time of image creation. */
+ uint32_t u32ParentTimestamp;
+ /** Relative path to the parent image. */
+ char *pszParentFilename;
+
+ /** The Block Allocation Table. */
+ uint32_t *pBlockAllocationTable;
+ /** Number of entries in the table. */
+ uint32_t cBlockAllocationTableEntries;
+
+ /** Size of one data block. */
+ uint32_t cbDataBlock;
+ /** Sectors per data block. */
+ uint32_t cSectorsPerDataBlock;
+ /** Length of the sector bitmap in bytes. */
+ uint32_t cbDataBlockBitmap;
+ /** A copy of the disk footer. */
+ VHDFooter vhdFooterCopy;
+ /** Current end offset of the file (without the disk footer). */
+ uint64_t uCurrentEndOfFile;
+ /** Size of the data block bitmap in sectors. */
+ uint32_t cDataBlockBitmapSectors;
+ /** Start of the block allocation table. */
+ uint64_t uBlockAllocationTableOffset;
+ /** Buffer to hold block's bitmap for bit search operations. */
+ uint8_t *pu8Bitmap;
+ /** Offset to the next data structure (dynamic disk header). */
+ uint64_t u64DataOffset;
+ /** Flag to force dynamic disk header update. */
+ bool fDynHdrNeedsUpdate;
+ /** The static region list. */
+ VDREGIONLIST RegionList;
+} VHDIMAGE, *PVHDIMAGE;
+
+/**
+ * Structure tracking the expansion process of the image
+ * for async access.
+ */
+typedef struct VHDIMAGEEXPAND
+{
+ /** Flag indicating the status of each step. */
+ volatile uint32_t fFlags;
+ /** The index in the block allocation table which is written. */
+ uint32_t idxBatAllocated;
+ /** Big endian representation of the block index
+ * which is written in the BAT. */
+ uint32_t idxBlockBe;
+ /** Old end of the file - used for rollback in case of an error. */
+ uint64_t cbEofOld;
+ /** Sector bitmap written to the new block - variable in size. */
+ uint8_t au8Bitmap[1];
+} VHDIMAGEEXPAND, *PVHDIMAGEEXPAND;
+
+/**
+ * Flag defines
+ */
+#define VHDIMAGEEXPAND_STEP_IN_PROGRESS (0x0)
+#define VHDIMAGEEXPAND_STEP_FAILED (0x2)
+#define VHDIMAGEEXPAND_STEP_SUCCESS (0x3)
+/** All steps completed successfully. */
+#define VHDIMAGEEXPAND_ALL_SUCCESS (0xff)
+/** All steps completed (no success indicator) */
+#define VHDIMAGEEXPAND_ALL_COMPLETE (0xaa)
+
+/** Every status field has 2 bits so we can encode 4 steps in one byte. */
+#define VHDIMAGEEXPAND_STATUS_MASK 0x03
+#define VHDIMAGEEXPAND_BLOCKBITMAP_STATUS_SHIFT 0x00
+#define VHDIMAGEEXPAND_USERBLOCK_STATUS_SHIFT 0x02
+#define VHDIMAGEEXPAND_FOOTER_STATUS_SHIFT 0x04
+#define VHDIMAGEEXPAND_BAT_STATUS_SHIFT 0x06
+
+/**
+ * Helper macros to get and set the status field.
+ */
+#define VHDIMAGEEXPAND_STATUS_GET(fFlags, cShift) \
+ (((fFlags) >> (cShift)) & VHDIMAGEEXPAND_STATUS_MASK)
+#define VHDIMAGEEXPAND_STATUS_SET(fFlags, cShift, uVal) \
+ ASMAtomicOrU32(&(fFlags), ((uVal) & VHDIMAGEEXPAND_STATUS_MASK) << (cShift))
+
+
+/*********************************************************************************************************************************
+* Static Variables *
+*********************************************************************************************************************************/
+
+/** NULL-terminated array of supported file extensions. */
+static const VDFILEEXTENSION s_aVhdFileExtensions[] =
+{
+ {"vhd", VDTYPE_HDD},
+ {NULL, VDTYPE_INVALID}
+};
+
+
+/*********************************************************************************************************************************
+* Internal Functions *
+*********************************************************************************************************************************/
+
+
+/**
+ * Internal: Compute and update header checksum.
+ */
+static uint32_t vhdChecksum(void *pHeader, uint32_t cbSize)
+{
+ uint32_t u32ChkSum = 0;
+ for (uint32_t i = 0; i < cbSize; i++)
+ u32ChkSum += ((unsigned char *)pHeader)[i];
+ return ~u32ChkSum;
+}
+
+/**
+ * Internal: Convert filename to UTF16 with appropriate endianness.
+ */
+static int vhdFilenameToUtf16(const char *pszFilename, uint16_t *pu16Buf,
+ uint32_t cbBufSize, uint32_t *pcbActualSize,
+ bool fBigEndian)
+{
+ int rc;
+ PRTUTF16 pTmp16 = NULL;
+ size_t cTmp16Len;
+
+ rc = RTStrToUtf16(pszFilename, &pTmp16);
+ if (RT_SUCCESS(rc))
+ {
+ cTmp16Len = RTUtf16Len(pTmp16);
+ if (cTmp16Len * sizeof(*pTmp16) <= cbBufSize)
+ {
+ if (fBigEndian)
+ for (unsigned i = 0; i < cTmp16Len; i++)
+ pu16Buf[i] = RT_H2BE_U16(pTmp16[i]);
+ else
+ memcpy(pu16Buf, pTmp16, cTmp16Len * sizeof(*pTmp16));
+ if (pcbActualSize)
+ *pcbActualSize = (uint32_t)(cTmp16Len * sizeof(*pTmp16));
+ }
+ else
+ rc = VERR_FILENAME_TOO_LONG;
+ }
+
+ if (pTmp16)
+ RTUtf16Free(pTmp16);
+ return rc;
+}
+
+/**
+ * Internal: Update one locator entry.
+ */
+static int vhdLocatorUpdate(PVHDIMAGE pImage, PVHDPLE pLocator, const char *pszFilename)
+{
+ int rc = VINF_SUCCESS;
+ uint32_t cb = 0;
+ uint32_t cbMaxLen = RT_BE2H_U32(pLocator->u32DataSpace);
+ void *pvBuf = RTMemTmpAllocZ(cbMaxLen);
+ char *pszTmp;
+
+ if (!pvBuf)
+ return VERR_NO_MEMORY;
+
+ switch (RT_BE2H_U32(pLocator->u32Code))
+ {
+ case VHD_PLATFORM_CODE_WI2R:
+ {
+ if (RTPathStartsWithRoot(pszFilename))
+ {
+ /* Convert to relative path. */
+ char szPath[RTPATH_MAX];
+ rc = RTPathCalcRelative(szPath, sizeof(szPath), pImage->pszFilename, true /*fFromFile*/, pszFilename);
+ if (RT_SUCCESS(rc))
+ {
+ /* Update plain relative name. */
+ cb = (uint32_t)strlen(szPath);
+ if (cb > cbMaxLen)
+ {
+ rc = VERR_FILENAME_TOO_LONG;
+ break;
+ }
+ memcpy(pvBuf, szPath, cb);
+ }
+ }
+ else
+ {
+ /* Update plain relative name. */
+ cb = (uint32_t)strlen(pszFilename);
+ if (cb > cbMaxLen)
+ {
+ rc = VERR_FILENAME_TOO_LONG;
+ break;
+ }
+ memcpy(pvBuf, pszFilename, cb);
+ }
+ if (RT_SUCCESS(rc))
+ pLocator->u32DataLength = RT_H2BE_U32(cb);
+ break;
+ }
+ case VHD_PLATFORM_CODE_WI2K:
+ /* Update plain absolute name. */
+ rc = RTPathAbs(pszFilename, (char *)pvBuf, cbMaxLen);
+ if (RT_SUCCESS(rc))
+ {
+ cb = (uint32_t)strlen((const char *)pvBuf);
+ pLocator->u32DataLength = RT_H2BE_U32(cb);
+ }
+ break;
+ case VHD_PLATFORM_CODE_W2RU:
+ if (RTPathStartsWithRoot(pszFilename))
+ {
+ /* Convert to relative path. */
+ char szPath[RTPATH_MAX];
+ rc = RTPathCalcRelative(szPath, sizeof(szPath), pImage->pszFilename, true /*fFromFile*/, pszFilename);
+ if (RT_SUCCESS(rc))
+ rc = vhdFilenameToUtf16(szPath, (uint16_t *)pvBuf, cbMaxLen, &cb, false);
+ }
+ else
+ {
+ /* Update unicode relative name. */
+ rc = vhdFilenameToUtf16(pszFilename, (uint16_t *)pvBuf, cbMaxLen, &cb, false);
+ }
+
+ if (RT_SUCCESS(rc))
+ pLocator->u32DataLength = RT_H2BE_U32(cb);
+ break;
+ case VHD_PLATFORM_CODE_W2KU:
+ /* Update unicode absolute name. */
+ pszTmp = (char*)RTMemTmpAllocZ(cbMaxLen);
+ if (!pszTmp)
+ {
+ rc = VERR_NO_MEMORY;
+ break;
+ }
+ rc = RTPathAbs(pszFilename, pszTmp, cbMaxLen);
+ if (RT_FAILURE(rc))
+ {
+ RTMemTmpFree(pszTmp);
+ break;
+ }
+ rc = vhdFilenameToUtf16(pszTmp, (uint16_t *)pvBuf, cbMaxLen, &cb, false);
+ RTMemTmpFree(pszTmp);
+ if (RT_SUCCESS(rc))
+ pLocator->u32DataLength = RT_H2BE_U32(cb);
+ break;
+ default:
+ rc = VERR_NOT_IMPLEMENTED;
+ break;
+ }
+
+ if (RT_SUCCESS(rc))
+ {
+ Assert(cb > 0);
+ rc = vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage,
+ RT_BE2H_U64(pLocator->u64DataOffset),
+ pvBuf, cb);
+ }
+
+ if (pvBuf)
+ RTMemTmpFree(pvBuf);
+ return rc;
+}
+
+/**
+ * Internal: Update dynamic disk header from VHDIMAGE.
+ */
+static int vhdDynamicHeaderUpdate(PVHDIMAGE pImage)
+{
+ VHDDynamicDiskHeader ddh;
+ int rc, i;
+
+ if (!pImage)
+ return VERR_VD_NOT_OPENED;
+
+ rc = vdIfIoIntFileReadSync(pImage->pIfIo, pImage->pStorage,
+ pImage->u64DataOffset, &ddh, sizeof(ddh));
+ if (RT_FAILURE(rc))
+ return rc;
+ if (memcmp(ddh.Cookie, VHD_DYNAMIC_DISK_HEADER_COOKIE, VHD_DYNAMIC_DISK_HEADER_COOKIE_SIZE) != 0)
+ return VERR_VD_VHD_INVALID_HEADER;
+
+ uint32_t u32Checksum = RT_BE2H_U32(ddh.Checksum);
+ ddh.Checksum = 0;
+ if (u32Checksum != vhdChecksum(&ddh, sizeof(ddh)))
+ return VERR_VD_VHD_INVALID_HEADER;
+
+ /* Update parent's timestamp. */
+ ddh.ParentTimestamp = RT_H2BE_U32(pImage->u32ParentTimestamp);
+ /* Update parent's filename. */
+ if (pImage->pszParentFilename)
+ {
+ rc = vhdFilenameToUtf16(RTPathFilename(pImage->pszParentFilename),
+ ddh.ParentUnicodeName, sizeof(ddh.ParentUnicodeName) - 1, NULL, true);
+ if (RT_FAILURE(rc))
+ return rc;
+ }
+
+ /* Update parent's locators. */
+ for (i = 0; i < VHD_MAX_LOCATOR_ENTRIES; i++)
+ {
+ /* Skip empty locators */
+ if ( ddh.ParentLocatorEntry[i].u32Code != RT_H2BE_U32(VHD_PLATFORM_CODE_NONE)
+ && pImage->pszParentFilename)
+ {
+ rc = vhdLocatorUpdate(pImage, &ddh.ParentLocatorEntry[i], pImage->pszParentFilename);
+ if (RT_FAILURE(rc))
+ return rc;
+ }
+ }
+ /* Update parent's UUID */
+ memcpy(ddh.ParentUuid, pImage->ParentUuid.au8, sizeof(ddh.ParentUuid));
+
+ /* Update data offset and number of table entries. */
+ ddh.MaxTableEntries = RT_H2BE_U32(pImage->cBlockAllocationTableEntries);
+
+ ddh.Checksum = 0;
+ ddh.Checksum = RT_H2BE_U32(vhdChecksum(&ddh, sizeof(ddh)));
+ rc = vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage,
+ pImage->u64DataOffset, &ddh, sizeof(ddh));
+ return rc;
+}
+
+/**
+ * Internal: Update the VHD footer.
+ */
+static int vhdUpdateFooter(PVHDIMAGE pImage)
+{
+ int rc = VINF_SUCCESS;
+
+ /* Update fields which can change. */
+ pImage->vhdFooterCopy.CurSize = RT_H2BE_U64(pImage->cbSize);
+ pImage->vhdFooterCopy.DiskGeometryCylinder = RT_H2BE_U16(pImage->PCHSGeometry.cCylinders);
+ pImage->vhdFooterCopy.DiskGeometryHeads = pImage->PCHSGeometry.cHeads;
+ pImage->vhdFooterCopy.DiskGeometrySectors = pImage->PCHSGeometry.cSectors;
+
+ pImage->vhdFooterCopy.Checksum = 0;
+ pImage->vhdFooterCopy.Checksum = RT_H2BE_U32(vhdChecksum(&pImage->vhdFooterCopy, sizeof(VHDFooter)));
+
+ if (pImage->pBlockAllocationTable)
+ rc = vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage, 0,
+ &pImage->vhdFooterCopy, sizeof(VHDFooter));
+
+ if (RT_SUCCESS(rc))
+ rc = vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage,
+ pImage->uCurrentEndOfFile, &pImage->vhdFooterCopy,
+ sizeof(VHDFooter));
+
+ return rc;
+}
+
+/**
+ * Internal. Flush image data to disk.
+ */
+static int vhdFlushImage(PVHDIMAGE pImage)
+{
+ int rc = VINF_SUCCESS;
+
+ if (pImage->uOpenFlags & VD_OPEN_FLAGS_READONLY)
+ return VINF_SUCCESS;
+
+ if (pImage->pBlockAllocationTable)
+ {
+ /*
+ * This is an expanding image. Write the BAT and copy of the disk footer.
+ */
+ size_t cbBlockAllocationTableToWrite = pImage->cBlockAllocationTableEntries * sizeof(uint32_t);
+ uint32_t *pBlockAllocationTableToWrite = (uint32_t *)RTMemAllocZ(cbBlockAllocationTableToWrite);
+
+ if (!pBlockAllocationTableToWrite)
+ return VERR_NO_MEMORY;
+
+ /*
+ * The BAT entries have to be stored in big endian format.
+ */
+ for (unsigned i = 0; i < pImage->cBlockAllocationTableEntries; i++)
+ pBlockAllocationTableToWrite[i] = RT_H2BE_U32(pImage->pBlockAllocationTable[i]);
+
+ /*
+ * Write the block allocation table after the copy of the disk footer and the dynamic disk header.
+ */
+ vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage, pImage->uBlockAllocationTableOffset,
+ pBlockAllocationTableToWrite, cbBlockAllocationTableToWrite);
+ if (pImage->fDynHdrNeedsUpdate)
+ rc = vhdDynamicHeaderUpdate(pImage);
+ RTMemFree(pBlockAllocationTableToWrite);
+ }
+
+ if (RT_SUCCESS(rc))
+ rc = vhdUpdateFooter(pImage);
+
+ if (RT_SUCCESS(rc))
+ rc = vdIfIoIntFileFlushSync(pImage->pIfIo, pImage->pStorage);
+
+ return rc;
+}
+
+/**
+ * Internal. Free all allocated space for representing an image except pImage,
+ * and optionally delete the image from disk.
+ */
+static int vhdFreeImage(PVHDIMAGE pImage, bool fDelete)
+{
+ int rc = VINF_SUCCESS;
+
+ /* Freeing a never allocated image (e.g. because the open failed) is
+ * not signalled as an error. After all nothing bad happens. */
+ if (pImage)
+ {
+ if (pImage->pStorage)
+ {
+ /* No point updating the file that is deleted anyway. */
+ if (!fDelete)
+ vhdFlushImage(pImage);
+
+ rc = vdIfIoIntFileClose(pImage->pIfIo, pImage->pStorage);
+ pImage->pStorage = NULL;
+ }
+
+ if (pImage->pszParentFilename)
+ {
+ RTStrFree(pImage->pszParentFilename);
+ pImage->pszParentFilename = NULL;
+ }
+ if (pImage->pBlockAllocationTable)
+ {
+ RTMemFree(pImage->pBlockAllocationTable);
+ pImage->pBlockAllocationTable = NULL;
+ }
+ if (pImage->pu8Bitmap)
+ {
+ RTMemFree(pImage->pu8Bitmap);
+ pImage->pu8Bitmap = NULL;
+ }
+
+ if (fDelete && pImage->pszFilename)
+ {
+ int rc2 = vdIfIoIntFileDelete(pImage->pIfIo, pImage->pszFilename);
+ if (RT_SUCCESS(rc))
+ rc = rc2;
+ }
+ }
+
+ LogFlowFunc(("returns %Rrc\n", rc));
+ return rc;
+}
+
+/* 946684800 is the number of seconds between 1/1/1970 and 1/1/2000 */
+#define VHD_TO_UNIX_EPOCH_SECONDS UINT64_C(946684800)
+
+static uint32_t vhdRtTime2VhdTime(PCRTTIMESPEC pRtTimestamp)
+{
+ uint64_t u64Seconds = RTTimeSpecGetSeconds(pRtTimestamp);
+ return (uint32_t)(u64Seconds - VHD_TO_UNIX_EPOCH_SECONDS);
+}
+
+static void vhdTime2RtTime(PRTTIMESPEC pRtTimestamp, uint32_t u32VhdTimestamp)
+{
+ RTTimeSpecSetSeconds(pRtTimestamp, VHD_TO_UNIX_EPOCH_SECONDS + u32VhdTimestamp);
+}
+
+/**
+ * Internal: Allocates the block bitmap rounding up to the next 32bit or 64bit boundary.
+ * Can be freed with RTMemFree. The memory is zeroed.
+ */
+DECLINLINE(uint8_t *)vhdBlockBitmapAllocate(PVHDIMAGE pImage)
+{
+#ifdef RT_ARCH_AMD64
+ return (uint8_t *)RTMemAllocZ(pImage->cbDataBlockBitmap + 8);
+#else
+ return (uint8_t *)RTMemAllocZ(pImage->cbDataBlockBitmap + 4);
+#endif
+}
+
+/**
+ * Internal: called when the async expansion process completed (failure or success).
+ * Will do the necessary rollback if an error occurred.
+ */
+static int vhdAsyncExpansionComplete(PVHDIMAGE pImage, PVDIOCTX pIoCtx, PVHDIMAGEEXPAND pExpand)
+{
+ int rc = VINF_SUCCESS;
+ uint32_t fFlags = ASMAtomicReadU32(&pExpand->fFlags);
+ bool fIoInProgress = false;
+
+ /* Quick path, check if everything succeeded. */
+ if (fFlags == VHDIMAGEEXPAND_ALL_SUCCESS)
+ {
+ pImage->pBlockAllocationTable[pExpand->idxBatAllocated] = RT_BE2H_U32(pExpand->idxBlockBe);
+ RTMemFree(pExpand);
+ }
+ else
+ {
+ uint32_t uStatus;
+
+ uStatus = VHDIMAGEEXPAND_STATUS_GET(pExpand->fFlags, VHDIMAGEEXPAND_BAT_STATUS_SHIFT);
+ if ( uStatus == VHDIMAGEEXPAND_STEP_FAILED
+ || uStatus == VHDIMAGEEXPAND_STEP_SUCCESS)
+ {
+ /* Undo and restore the old value. */
+ pImage->pBlockAllocationTable[pExpand->idxBatAllocated] = ~0U;
+
+ /* Restore the old value on the disk.
+ * No need for a completion callback because we can't
+ * do anything if this fails. */
+ if (uStatus == VHDIMAGEEXPAND_STEP_SUCCESS)
+ {
+ rc = vdIfIoIntFileWriteMeta(pImage->pIfIo, pImage->pStorage,
+ pImage->uBlockAllocationTableOffset
+ + pExpand->idxBatAllocated * sizeof(uint32_t),
+ &pImage->pBlockAllocationTable[pExpand->idxBatAllocated],
+ sizeof(uint32_t), pIoCtx, NULL, NULL);
+ fIoInProgress |= rc == VERR_VD_ASYNC_IO_IN_PROGRESS;
+ }
+ }
+
+ /* Restore old size (including the footer because another application might
+ * fill up the free space making it impossible to add the footer)
+ * and add the footer at the right place again. */
+ rc = vdIfIoIntFileSetSize(pImage->pIfIo, pImage->pStorage,
+ pExpand->cbEofOld + sizeof(VHDFooter));
+ AssertRC(rc);
+
+ pImage->uCurrentEndOfFile = pExpand->cbEofOld;
+ rc = vdIfIoIntFileWriteMeta(pImage->pIfIo, pImage->pStorage,
+ pImage->uCurrentEndOfFile,
+ &pImage->vhdFooterCopy, sizeof(VHDFooter),
+ pIoCtx, NULL, NULL);
+ fIoInProgress |= rc == VERR_VD_ASYNC_IO_IN_PROGRESS;
+ }
+
+ return fIoInProgress ? VERR_VD_ASYNC_IO_IN_PROGRESS : rc;
+}
+
+static int vhdAsyncExpansionStepCompleted(void *pBackendData, PVDIOCTX pIoCtx, void *pvUser, int rcReq, unsigned iStep)
+{
+ PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
+ PVHDIMAGEEXPAND pExpand = (PVHDIMAGEEXPAND)pvUser;
+
+ LogFlowFunc(("pBackendData=%#p pIoCtx=%#p pvUser=%#p rcReq=%Rrc iStep=%u\n",
+ pBackendData, pIoCtx, pvUser, rcReq, iStep));
+
+ if (RT_SUCCESS(rcReq))
+ VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, iStep, VHDIMAGEEXPAND_STEP_SUCCESS);
+ else
+ VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, iStep, VHDIMAGEEXPAND_STEP_FAILED);
+
+ if ((pExpand->fFlags & VHDIMAGEEXPAND_ALL_COMPLETE) == VHDIMAGEEXPAND_ALL_COMPLETE)
+ return vhdAsyncExpansionComplete(pImage, pIoCtx, pExpand);
+
+ return VERR_VD_ASYNC_IO_IN_PROGRESS;
+}
+
+static DECLCALLBACK(int) vhdAsyncExpansionDataBlockBitmapComplete(void *pBackendData, PVDIOCTX pIoCtx, void *pvUser, int rcReq)
+{
+ return vhdAsyncExpansionStepCompleted(pBackendData, pIoCtx, pvUser, rcReq, VHDIMAGEEXPAND_BLOCKBITMAP_STATUS_SHIFT);
+}
+
+static DECLCALLBACK(int) vhdAsyncExpansionDataComplete(void *pBackendData, PVDIOCTX pIoCtx, void *pvUser, int rcReq)
+{
+ return vhdAsyncExpansionStepCompleted(pBackendData, pIoCtx, pvUser, rcReq, VHDIMAGEEXPAND_USERBLOCK_STATUS_SHIFT);
+}
+
+static DECLCALLBACK(int) vhdAsyncExpansionBatUpdateComplete(void *pBackendData, PVDIOCTX pIoCtx, void *pvUser, int rcReq)
+{
+ return vhdAsyncExpansionStepCompleted(pBackendData, pIoCtx, pvUser, rcReq, VHDIMAGEEXPAND_BAT_STATUS_SHIFT);
+}
+
+static DECLCALLBACK(int) vhdAsyncExpansionFooterUpdateComplete(void *pBackendData, PVDIOCTX pIoCtx, void *pvUser, int rcReq)
+{
+ return vhdAsyncExpansionStepCompleted(pBackendData, pIoCtx, pvUser, rcReq, VHDIMAGEEXPAND_FOOTER_STATUS_SHIFT);
+}
+
+static int vhdLoadDynamicDisk(PVHDIMAGE pImage, uint64_t uDynamicDiskHeaderOffset)
+{
+ VHDDynamicDiskHeader vhdDynamicDiskHeader;
+ int rc = VINF_SUCCESS;
+ uint32_t *pBlockAllocationTable;
+ uint64_t uBlockAllocationTableOffset;
+ unsigned i = 0;
+
+ Log(("Open a dynamic disk.\n"));
+
+ /*
+ * Read the dynamic disk header.
+ */
+ rc = vdIfIoIntFileReadSync(pImage->pIfIo, pImage->pStorage, uDynamicDiskHeaderOffset,
+ &vhdDynamicDiskHeader, sizeof(VHDDynamicDiskHeader));
+ if (memcmp(vhdDynamicDiskHeader.Cookie, VHD_DYNAMIC_DISK_HEADER_COOKIE, VHD_DYNAMIC_DISK_HEADER_COOKIE_SIZE))
+ return VERR_INVALID_PARAMETER;
+
+ pImage->cbDataBlock = RT_BE2H_U32(vhdDynamicDiskHeader.BlockSize);
+ LogFlowFunc(("BlockSize=%u\n", pImage->cbDataBlock));
+ pImage->cBlockAllocationTableEntries = RT_BE2H_U32(vhdDynamicDiskHeader.MaxTableEntries);
+ LogFlowFunc(("MaxTableEntries=%lu\n", pImage->cBlockAllocationTableEntries));
+ AssertMsg(!(pImage->cbDataBlock % VHD_SECTOR_SIZE), ("%s: Data block size is not a multiple of %!\n", __FUNCTION__, VHD_SECTOR_SIZE));
+
+ /*
+ * Bail out if the number of BAT entries exceeds the number of sectors for a maximum image.
+ * Lower the number of sectors in the BAT as a few sectors are already occupied by the footers
+ * and headers.
+ */
+ if (pImage->cBlockAllocationTableEntries > (VHD_MAX_SECTORS - 2))
+ return VERR_VD_VHD_INVALID_HEADER;
+
+ pImage->cSectorsPerDataBlock = pImage->cbDataBlock / VHD_SECTOR_SIZE;
+ LogFlowFunc(("SectorsPerDataBlock=%u\n", pImage->cSectorsPerDataBlock));
+
+ /*
+ * Every block starts with a bitmap indicating which sectors are valid and which are not.
+ * We store the size of it to be able to calculate the real offset.
+ */
+ pImage->cbDataBlockBitmap = pImage->cSectorsPerDataBlock / 8;
+ pImage->cDataBlockBitmapSectors = pImage->cbDataBlockBitmap / VHD_SECTOR_SIZE;
+ /* Round up to full sector size */
+ if (pImage->cbDataBlockBitmap % VHD_SECTOR_SIZE > 0)
+ pImage->cDataBlockBitmapSectors++;
+ LogFlowFunc(("cbDataBlockBitmap=%u\n", pImage->cbDataBlockBitmap));
+ LogFlowFunc(("cDataBlockBitmapSectors=%u\n", pImage->cDataBlockBitmapSectors));
+
+ pImage->pu8Bitmap = vhdBlockBitmapAllocate(pImage);
+ if (!pImage->pu8Bitmap)
+ return VERR_NO_MEMORY;
+
+ pBlockAllocationTable = (uint32_t *)RTMemAllocZ(pImage->cBlockAllocationTableEntries * sizeof(uint32_t));
+ if (!pBlockAllocationTable)
+ return VERR_NO_MEMORY;
+
+ /*
+ * Read the table.
+ */
+ uBlockAllocationTableOffset = RT_BE2H_U64(vhdDynamicDiskHeader.TableOffset);
+ LogFlowFunc(("uBlockAllocationTableOffset=%llu\n", uBlockAllocationTableOffset));
+ pImage->uBlockAllocationTableOffset = uBlockAllocationTableOffset;
+ rc = vdIfIoIntFileReadSync(pImage->pIfIo, pImage->pStorage,
+ uBlockAllocationTableOffset, pBlockAllocationTable,
+ pImage->cBlockAllocationTableEntries * sizeof(uint32_t));
+ if (RT_FAILURE(rc))
+ {
+ RTMemFree(pBlockAllocationTable);
+ return rc;
+ }
+
+ /*
+ * Because the offset entries inside the allocation table are stored big endian
+ * we need to convert them into host endian.
+ */
+ pImage->pBlockAllocationTable = (uint32_t *)RTMemAllocZ(pImage->cBlockAllocationTableEntries * sizeof(uint32_t));
+ if (!pImage->pBlockAllocationTable)
+ {
+ RTMemFree(pBlockAllocationTable);
+ return VERR_NO_MEMORY;
+ }
+
+ for (i = 0; i < pImage->cBlockAllocationTableEntries; i++)
+ pImage->pBlockAllocationTable[i] = RT_BE2H_U32(pBlockAllocationTable[i]);
+
+ RTMemFree(pBlockAllocationTable);
+
+ if (pImage->uImageFlags & VD_IMAGE_FLAGS_DIFF)
+ memcpy(pImage->ParentUuid.au8, vhdDynamicDiskHeader.ParentUuid, sizeof(pImage->ParentUuid));
+
+ return rc;
+}
+
+static int vhdOpenImage(PVHDIMAGE pImage, unsigned uOpenFlags)
+{
+ uint64_t FileSize;
+ VHDFooter vhdFooter;
+
+ pImage->uOpenFlags = uOpenFlags;
+
+ pImage->pIfError = VDIfErrorGet(pImage->pVDIfsDisk);
+ pImage->pIfIo = VDIfIoIntGet(pImage->pVDIfsImage);
+ AssertPtrReturn(pImage->pIfIo, VERR_INVALID_PARAMETER);
+
+ /*
+ * Open the image.
+ */
+ int rc = vdIfIoIntFileOpen(pImage->pIfIo, pImage->pszFilename,
+ VDOpenFlagsToFileOpenFlags(uOpenFlags,
+ false /* fCreate */),
+ &pImage->pStorage);
+ if (RT_FAILURE(rc))
+ {
+ /* Do NOT signal an appropriate error here, as the VD layer has the
+ * choice of retrying the open if it failed. */
+ return rc;
+ }
+
+ rc = vdIfIoIntFileGetSize(pImage->pIfIo, pImage->pStorage, &FileSize);
+ pImage->uCurrentEndOfFile = FileSize - sizeof(VHDFooter);
+
+ rc = vdIfIoIntFileReadSync(pImage->pIfIo, pImage->pStorage, pImage->uCurrentEndOfFile,
+ &vhdFooter, sizeof(VHDFooter));
+ if (RT_SUCCESS(rc))
+ {
+ if (memcmp(vhdFooter.Cookie, VHD_FOOTER_COOKIE, VHD_FOOTER_COOKIE_SIZE) != 0)
+ {
+ /*
+ * There is also a backup header at the beginning in case the image got corrupted.
+ * Such corrupted images are detected here to let the open handler repair it later.
+ */
+ rc = vdIfIoIntFileReadSync(pImage->pIfIo, pImage->pStorage, 0,
+ &vhdFooter, sizeof(VHDFooter));
+ if (RT_SUCCESS(rc))
+ {
+ if (memcmp(vhdFooter.Cookie, VHD_FOOTER_COOKIE, VHD_FOOTER_COOKIE_SIZE) != 0)
+ rc = VERR_VD_VHD_INVALID_HEADER;
+ else
+ rc = VERR_VD_IMAGE_CORRUPTED;
+ }
+ }
+ }
+
+ if (RT_FAILURE(rc))
+ {
+ vhdFreeImage(pImage, false);
+ return rc;
+ }
+
+ switch (RT_BE2H_U32(vhdFooter.DiskType))
+ {
+ case VHD_FOOTER_DISK_TYPE_FIXED:
+ pImage->uImageFlags |= VD_IMAGE_FLAGS_FIXED;
+ break;
+ case VHD_FOOTER_DISK_TYPE_DYNAMIC:
+ pImage->uImageFlags &= ~VD_IMAGE_FLAGS_FIXED;
+ break;
+ case VHD_FOOTER_DISK_TYPE_DIFFERENCING:
+ pImage->uImageFlags |= VD_IMAGE_FLAGS_DIFF;
+ pImage->uImageFlags &= ~VD_IMAGE_FLAGS_FIXED;
+ break;
+ default:
+ vhdFreeImage(pImage, false);
+ return VERR_NOT_IMPLEMENTED;
+ }
+
+ pImage->cbSize = RT_BE2H_U64(vhdFooter.CurSize);
+ pImage->LCHSGeometry.cCylinders = 0;
+ pImage->LCHSGeometry.cHeads = 0;
+ pImage->LCHSGeometry.cSectors = 0;
+ pImage->PCHSGeometry.cCylinders = RT_BE2H_U16(vhdFooter.DiskGeometryCylinder);
+ pImage->PCHSGeometry.cHeads = vhdFooter.DiskGeometryHeads;
+ pImage->PCHSGeometry.cSectors = vhdFooter.DiskGeometrySectors;
+
+ /*
+ * Copy of the disk footer.
+ * If we allocate new blocks in differencing disks on write access
+ * the footer is overwritten. We need to write it at the end of the file.
+ */
+ memcpy(&pImage->vhdFooterCopy, &vhdFooter, sizeof(VHDFooter));
+
+ /*
+ * Is there a better way?
+ */
+ memcpy(&pImage->ImageUuid, &vhdFooter.UniqueID, 16);
+
+ pImage->u64DataOffset = RT_BE2H_U64(vhdFooter.DataOffset);
+ LogFlowFunc(("DataOffset=%llu\n", pImage->u64DataOffset));
+
+ if (!(pImage->uImageFlags & VD_IMAGE_FLAGS_FIXED))
+ rc = vhdLoadDynamicDisk(pImage, pImage->u64DataOffset);
+
+ if (RT_SUCCESS(rc))
+ {
+ PVDREGIONDESC pRegion = &pImage->RegionList.aRegions[0];
+ pImage->RegionList.fFlags = 0;
+ pImage->RegionList.cRegions = 1;
+
+ pRegion->offRegion = 0; /* Disk start. */
+ pRegion->cbBlock = 512;
+ pRegion->enmDataForm = VDREGIONDATAFORM_RAW;
+ pRegion->enmMetadataForm = VDREGIONMETADATAFORM_NONE;
+ pRegion->cbData = 512;
+ pRegion->cbMetadata = 0;
+ pRegion->cRegionBlocksOrBytes = pImage->cbSize;
+ }
+ else
+ vhdFreeImage(pImage, false);
+ return rc;
+}
+
+/**
+ * Internal: Checks if a sector in the block bitmap is set
+ */
+DECLINLINE(bool) vhdBlockBitmapSectorContainsData(PVHDIMAGE pImage, uint32_t cBlockBitmapEntry)
+{
+ uint32_t iBitmap = (cBlockBitmapEntry / 8); /* Byte in the block bitmap. */
+
+ /*
+ * The index of the bit in the byte of the data block bitmap.
+ * The most significant bit stands for a lower sector number.
+ */
+ uint8_t iBitInByte = (8-1) - (cBlockBitmapEntry % 8);
+ uint8_t *puBitmap = pImage->pu8Bitmap + iBitmap;
+
+ AssertMsg(puBitmap < (pImage->pu8Bitmap + pImage->cbDataBlockBitmap),
+ ("VHD: Current bitmap position exceeds maximum size of the bitmap\n"));
+
+ return ((*puBitmap) & RT_BIT(iBitInByte)) != 0;
+}
+
+/**
+ * Internal: Sets the given sector in the sector bitmap.
+ */
+DECLINLINE(bool) vhdBlockBitmapSectorSet(PVHDIMAGE pImage, uint8_t *pu8Bitmap, uint32_t cBlockBitmapEntry)
+{
+ RT_NOREF1(pImage);
+ uint32_t iBitmap = (cBlockBitmapEntry / 8); /* Byte in the block bitmap. */
+
+ /*
+ * The index of the bit in the byte of the data block bitmap.
+ * The most significant bit stands for a lower sector number.
+ */
+ uint8_t iBitInByte = (8-1) - (cBlockBitmapEntry % 8);
+ uint8_t *puBitmap = pu8Bitmap + iBitmap;
+
+ AssertMsg(puBitmap < (pu8Bitmap + pImage->cbDataBlockBitmap),
+ ("VHD: Current bitmap position exceeds maximum size of the bitmap\n"));
+
+ bool fClear = ((*puBitmap) & RT_BIT(iBitInByte)) == 0;
+ *puBitmap |= RT_BIT(iBitInByte);
+ return fClear;
+}
+
+/**
+ * Internal: Derive drive geometry from its size.
+ */
+static void vhdSetDiskGeometry(PVHDIMAGE pImage, uint64_t cbSize)
+{
+ uint64_t u64TotalSectors = cbSize / VHD_SECTOR_SIZE;
+ uint32_t u32CylinderTimesHeads, u32Heads, u32SectorsPerTrack;
+
+ if (u64TotalSectors > 65535 * 16 * 255)
+ {
+ /* ATA disks limited to 127 GB. */
+ u64TotalSectors = 65535 * 16 * 255;
+ }
+
+ if (u64TotalSectors >= 65535 * 16 * 63)
+ {
+ u32SectorsPerTrack = 255;
+ u32Heads = 16;
+ u32CylinderTimesHeads = u64TotalSectors / u32SectorsPerTrack;
+ }
+ else
+ {
+ u32SectorsPerTrack = 17;
+ u32CylinderTimesHeads = u64TotalSectors / u32SectorsPerTrack;
+
+ u32Heads = (u32CylinderTimesHeads + 1023) / 1024;
+
+ if (u32Heads < 4)
+ {
+ u32Heads = 4;
+ }
+ if (u32CylinderTimesHeads >= (u32Heads * 1024) || u32Heads > 16)
+ {
+ u32SectorsPerTrack = 31;
+ u32Heads = 16;
+ u32CylinderTimesHeads = u64TotalSectors / u32SectorsPerTrack;
+ }
+ if (u32CylinderTimesHeads >= (u32Heads * 1024))
+ {
+ u32SectorsPerTrack = 63;
+ u32Heads = 16;
+ u32CylinderTimesHeads = u64TotalSectors / u32SectorsPerTrack;
+ }
+ }
+ pImage->PCHSGeometry.cCylinders = u32CylinderTimesHeads / u32Heads;
+ pImage->PCHSGeometry.cHeads = u32Heads;
+ pImage->PCHSGeometry.cSectors = u32SectorsPerTrack;
+ pImage->LCHSGeometry.cCylinders = 0;
+ pImage->LCHSGeometry.cHeads = 0;
+ pImage->LCHSGeometry.cSectors = 0;
+}
+
+
+static uint32_t vhdAllocateParentLocators(PVHDIMAGE pImage, VHDDynamicDiskHeader *pDDH, uint64_t u64Offset)
+{
+ RT_NOREF1(pImage);
+ PVHDPLE pLocator = pDDH->ParentLocatorEntry;
+
+ /*
+ * The VHD spec states that the DataSpace field holds the number of sectors
+ * required to store the parent locator path.
+ * As it turned out VPC and Hyper-V store the amount of bytes reserved for the
+ * path and not the number of sectors.
+ */
+
+ /* Unicode absolute Windows path. */
+ pLocator->u32Code = RT_H2BE_U32(VHD_PLATFORM_CODE_W2KU);
+ pLocator->u32DataSpace = RT_H2BE_U32(VHD_ABSOLUTE_MAX_PATH * sizeof(RTUTF16));
+ pLocator->u64DataOffset = RT_H2BE_U64(u64Offset);
+ pLocator++;
+ u64Offset += VHD_ABSOLUTE_MAX_PATH * sizeof(RTUTF16);
+ /* Unicode relative Windows path. */
+ pLocator->u32Code = RT_H2BE_U32(VHD_PLATFORM_CODE_W2RU);
+ pLocator->u32DataSpace = RT_H2BE_U32(VHD_RELATIVE_MAX_PATH * sizeof(RTUTF16));
+ pLocator->u64DataOffset = RT_H2BE_U64(u64Offset);
+ u64Offset += VHD_RELATIVE_MAX_PATH * sizeof(RTUTF16);
+ return u64Offset;
+}
+
+/**
+ * Internal: Additional code for dynamic VHD image creation.
+ */
+static int vhdCreateDynamicImage(PVHDIMAGE pImage, uint64_t cbSize)
+{
+ int rc;
+ VHDDynamicDiskHeader DynamicDiskHeader;
+ uint32_t u32BlockAllocationTableSectors;
+ void *pvTmp = NULL;
+
+ memset(&DynamicDiskHeader, 0, sizeof(DynamicDiskHeader));
+
+ pImage->u64DataOffset = sizeof(VHDFooter);
+ pImage->cbDataBlock = VHD_BLOCK_SIZE; /* 2 MB */
+ pImage->cSectorsPerDataBlock = pImage->cbDataBlock / VHD_SECTOR_SIZE;
+ pImage->cbDataBlockBitmap = pImage->cSectorsPerDataBlock / 8;
+ pImage->cDataBlockBitmapSectors = pImage->cbDataBlockBitmap / VHD_SECTOR_SIZE;
+ /* Align to sector boundary */
+ if (pImage->cbDataBlockBitmap % VHD_SECTOR_SIZE > 0)
+ pImage->cDataBlockBitmapSectors++;
+ pImage->pu8Bitmap = vhdBlockBitmapAllocate(pImage);
+ if (!pImage->pu8Bitmap)
+ return vdIfError(pImage->pIfError, VERR_NO_MEMORY, RT_SRC_POS, N_("VHD: cannot allocate memory for bitmap storage"));
+
+ /* Initialize BAT. */
+ pImage->uBlockAllocationTableOffset = (uint64_t)sizeof(VHDFooter) + sizeof(VHDDynamicDiskHeader);
+ pImage->cBlockAllocationTableEntries = (uint32_t)((cbSize + pImage->cbDataBlock - 1) / pImage->cbDataBlock); /* Align table to the block size. */
+ u32BlockAllocationTableSectors = (pImage->cBlockAllocationTableEntries * sizeof(uint32_t) + VHD_SECTOR_SIZE - 1) / VHD_SECTOR_SIZE;
+ pImage->pBlockAllocationTable = (uint32_t *)RTMemAllocZ(pImage->cBlockAllocationTableEntries * sizeof(uint32_t));
+ if (!pImage->pBlockAllocationTable)
+ return vdIfError(pImage->pIfError, VERR_NO_MEMORY, RT_SRC_POS, N_("VHD: cannot allocate memory for BAT"));
+
+ for (unsigned i = 0; i < pImage->cBlockAllocationTableEntries; i++)
+ {
+ pImage->pBlockAllocationTable[i] = 0xFFFFFFFF; /* It is actually big endian. */
+ }
+
+ /* Round up to the sector size. */
+ if (pImage->uImageFlags & VD_IMAGE_FLAGS_DIFF) /* fix hyper-v unreadable error */
+ pImage->uCurrentEndOfFile = vhdAllocateParentLocators(pImage, &DynamicDiskHeader,
+ pImage->uBlockAllocationTableOffset + u32BlockAllocationTableSectors * VHD_SECTOR_SIZE);
+ else
+ pImage->uCurrentEndOfFile = pImage->uBlockAllocationTableOffset + u32BlockAllocationTableSectors * VHD_SECTOR_SIZE;
+
+ /* Set dynamic image size. */
+ pvTmp = RTMemTmpAllocZ(pImage->uCurrentEndOfFile + sizeof(VHDFooter));
+ if (!pvTmp)
+ return vdIfError(pImage->pIfError, VERR_NO_MEMORY, RT_SRC_POS, N_("VHD: cannot set the file size for '%s'"), pImage->pszFilename);
+
+ rc = vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage, 0, pvTmp,
+ pImage->uCurrentEndOfFile + sizeof(VHDFooter));
+ if (RT_FAILURE(rc))
+ {
+ RTMemTmpFree(pvTmp);
+ return vdIfError(pImage->pIfError, rc, RT_SRC_POS, N_("VHD: cannot set the file size for '%s'"), pImage->pszFilename);
+ }
+
+ RTMemTmpFree(pvTmp);
+
+ /* Initialize and write the dynamic disk header. */
+ memcpy(DynamicDiskHeader.Cookie, VHD_DYNAMIC_DISK_HEADER_COOKIE, sizeof(DynamicDiskHeader.Cookie));
+ DynamicDiskHeader.DataOffset = UINT64_C(0xFFFFFFFFFFFFFFFF); /* Initially the disk has no data. */
+ DynamicDiskHeader.TableOffset = RT_H2BE_U64(pImage->uBlockAllocationTableOffset);
+ DynamicDiskHeader.HeaderVersion = RT_H2BE_U32(VHD_DYNAMIC_DISK_HEADER_VERSION);
+ DynamicDiskHeader.BlockSize = RT_H2BE_U32(pImage->cbDataBlock);
+ DynamicDiskHeader.MaxTableEntries = RT_H2BE_U32(pImage->cBlockAllocationTableEntries);
+ /* Compute and update checksum. */
+ DynamicDiskHeader.Checksum = 0;
+ DynamicDiskHeader.Checksum = RT_H2BE_U32(vhdChecksum(&DynamicDiskHeader, sizeof(DynamicDiskHeader)));
+
+ rc = vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage, sizeof(VHDFooter),
+ &DynamicDiskHeader, sizeof(DynamicDiskHeader));
+ if (RT_FAILURE(rc))
+ return vdIfError(pImage->pIfError, rc, RT_SRC_POS, N_("VHD: cannot write dynamic disk header to image '%s'"), pImage->pszFilename);
+
+ /* Write BAT. */
+ rc = vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage, pImage->uBlockAllocationTableOffset,
+ pImage->pBlockAllocationTable,
+ pImage->cBlockAllocationTableEntries * sizeof(uint32_t));
+ if (RT_FAILURE(rc))
+ return vdIfError(pImage->pIfError, rc, RT_SRC_POS, N_("VHD: cannot write BAT to image '%s'"), pImage->pszFilename);
+
+ return rc;
+}
+
+/**
+ * Internal: The actual code for VHD image creation, both fixed and dynamic.
+ */
+static int vhdCreateImage(PVHDIMAGE pImage, uint64_t cbSize,
+ unsigned uImageFlags, const char *pszComment,
+ PCVDGEOMETRY pPCHSGeometry,
+ PCVDGEOMETRY pLCHSGeometry, PCRTUUID pUuid,
+ unsigned uOpenFlags,
+ PVDINTERFACEPROGRESS pIfProgress,
+ unsigned uPercentStart, unsigned uPercentSpan)
+{
+ RT_NOREF3(pszComment, pPCHSGeometry, pLCHSGeometry);
+ VHDFooter Footer;
+ RTTIMESPEC now;
+
+ pImage->uOpenFlags = uOpenFlags;
+ pImage->uImageFlags = uImageFlags;
+ pImage->pIfError = VDIfErrorGet(pImage->pVDIfsDisk);
+
+ int rc = vdIfIoIntFileOpen(pImage->pIfIo, pImage->pszFilename,
+ VDOpenFlagsToFileOpenFlags(uOpenFlags & ~VD_OPEN_FLAGS_READONLY,
+ true /* fCreate */),
+ &pImage->pStorage);
+ if (RT_SUCCESS(rc))
+ {
+ pImage->cbSize = cbSize;
+ pImage->ImageUuid = *pUuid;
+ RTUuidClear(&pImage->ParentUuid);
+ vhdSetDiskGeometry(pImage, cbSize);
+
+ /* Initialize the footer. */
+ memset(&Footer, 0, sizeof(Footer));
+ memcpy(Footer.Cookie, VHD_FOOTER_COOKIE, sizeof(Footer.Cookie));
+ Footer.Features = RT_H2BE_U32(0x2);
+ Footer.Version = RT_H2BE_U32(VHD_FOOTER_FILE_FORMAT_VERSION);
+ Footer.Timestamp = RT_H2BE_U32(vhdRtTime2VhdTime(RTTimeNow(&now)));
+ memcpy(Footer.CreatorApp, "vbox", sizeof(Footer.CreatorApp));
+ Footer.CreatorVer = RT_H2BE_U32(VBOX_VERSION);
+#ifdef RT_OS_DARWIN
+ Footer.CreatorOS = RT_H2BE_U32(0x4D616320); /* "Mac " */
+#else /* Virtual PC supports only two platforms atm, so everything else will be Wi2k. */
+ Footer.CreatorOS = RT_H2BE_U32(0x5769326B); /* "Wi2k" */
+#endif
+ Footer.OrigSize = RT_H2BE_U64(cbSize);
+ Footer.CurSize = Footer.OrigSize;
+ Footer.DiskGeometryCylinder = RT_H2BE_U16(pImage->PCHSGeometry.cCylinders);
+ Footer.DiskGeometryHeads = pImage->PCHSGeometry.cHeads;
+ Footer.DiskGeometrySectors = pImage->PCHSGeometry.cSectors;
+ memcpy(Footer.UniqueID, pImage->ImageUuid.au8, sizeof(Footer.UniqueID));
+ Footer.SavedState = 0;
+
+ if (uImageFlags & VD_IMAGE_FLAGS_FIXED)
+ {
+ Footer.DiskType = RT_H2BE_U32(VHD_FOOTER_DISK_TYPE_FIXED);
+ /*
+ * Initialize fixed image.
+ * "The size of the entire file is the size of the hard disk in
+ * the guest operating system plus the size of the footer."
+ */
+ pImage->u64DataOffset = VHD_FOOTER_DATA_OFFSET_FIXED;
+ pImage->uCurrentEndOfFile = cbSize;
+ rc = vdIfIoIntFileSetAllocationSize(pImage->pIfIo, pImage->pStorage, pImage->uCurrentEndOfFile + sizeof(VHDFooter),
+ 0 /* fFlags */, pIfProgress,
+ uPercentStart, uPercentSpan);
+ if (RT_FAILURE(rc))
+ rc = vdIfError(pImage->pIfError, rc, RT_SRC_POS, N_("VHD: cannot set the file size for '%s'"), pImage->pszFilename);
+ }
+ else
+ {
+ /*
+ * Initialize dynamic image.
+ *
+ * The overall structure of dynamic disk is:
+ *
+ * [Copy of hard disk footer (512 bytes)]
+ * [Dynamic disk header (1024 bytes)]
+ * [BAT (Block Allocation Table)]
+ * [Parent Locators]
+ * [Data block 1]
+ * [Data block 2]
+ * ...
+ * [Data block N]
+ * [Hard disk footer (512 bytes)]
+ */
+ Footer.DiskType = (uImageFlags & VD_IMAGE_FLAGS_DIFF)
+ ? RT_H2BE_U32(VHD_FOOTER_DISK_TYPE_DIFFERENCING)
+ : RT_H2BE_U32(VHD_FOOTER_DISK_TYPE_DYNAMIC);
+ /* We are half way thorough with creation of image, let the caller know. */
+ vdIfProgress(pIfProgress, (uPercentStart + uPercentSpan) / 2);
+
+ rc = vhdCreateDynamicImage(pImage, cbSize);
+ }
+
+ if (RT_SUCCESS(rc))
+ {
+ /* Compute and update the footer checksum. */
+ Footer.DataOffset = RT_H2BE_U64(pImage->u64DataOffset);
+ Footer.Checksum = 0;
+ Footer.Checksum = RT_H2BE_U32(vhdChecksum(&Footer, sizeof(Footer)));
+
+ pImage->vhdFooterCopy = Footer;
+
+ /* Store the footer */
+ rc = vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage, pImage->uCurrentEndOfFile,
+ &Footer, sizeof(Footer));
+ if (RT_SUCCESS(rc))
+ {
+ /* Dynamic images contain a copy of the footer at the very beginning of the file. */
+ if (!(uImageFlags & VD_IMAGE_FLAGS_FIXED))
+ {
+ /* Write the copy of the footer. */
+ rc = vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage, 0, &Footer, sizeof(Footer));
+ if (RT_FAILURE(rc))
+ rc = vdIfError(pImage->pIfError, rc, RT_SRC_POS, N_("VHD: cannot write a copy of footer to image '%s'"), pImage->pszFilename);
+ }
+ }
+ else
+ rc = vdIfError(pImage->pIfError, rc, RT_SRC_POS, N_("VHD: cannot write footer to image '%s'"), pImage->pszFilename);
+ }
+ }
+ else
+ rc = vdIfError(pImage->pIfError, rc, RT_SRC_POS, N_("VHD: cannot create image '%s'"), pImage->pszFilename);
+
+ if (RT_SUCCESS(rc))
+ vdIfProgress(pIfProgress, uPercentStart + uPercentSpan);
+
+ if (RT_SUCCESS(rc))
+ {
+ PVDREGIONDESC pRegion = &pImage->RegionList.aRegions[0];
+ pImage->RegionList.fFlags = 0;
+ pImage->RegionList.cRegions = 1;
+
+ pRegion->offRegion = 0; /* Disk start. */
+ pRegion->cbBlock = 512;
+ pRegion->enmDataForm = VDREGIONDATAFORM_RAW;
+ pRegion->enmMetadataForm = VDREGIONMETADATAFORM_NONE;
+ pRegion->cbData = 512;
+ pRegion->cbMetadata = 0;
+ pRegion->cRegionBlocksOrBytes = pImage->cbSize;
+ }
+ else
+ vhdFreeImage(pImage, rc != VERR_ALREADY_EXISTS);
+ return rc;
+}
+
+
+/** @interface_method_impl{VDIMAGEBACKEND,pfnProbe} */
+static DECLCALLBACK(int) vhdProbe(const char *pszFilename, PVDINTERFACE pVDIfsDisk,
+ PVDINTERFACE pVDIfsImage, VDTYPE enmDesiredType, VDTYPE *penmType)
+{
+ RT_NOREF(pVDIfsDisk, enmDesiredType);
+ LogFlowFunc(("pszFilename=\"%s\" pVDIfsDisk=%#p pVDIfsImage=%#p\n", pszFilename, pVDIfsDisk, pVDIfsImage));
+ PVDIOSTORAGE pStorage;
+ PVDINTERFACEIOINT pIfIo = VDIfIoIntGet(pVDIfsImage);
+ AssertPtrReturn(pIfIo, VERR_INVALID_PARAMETER);
+
+ int rc = vdIfIoIntFileOpen(pIfIo, pszFilename,
+ VDOpenFlagsToFileOpenFlags(VD_OPEN_FLAGS_READONLY,
+ false /* fCreate */),
+ &pStorage);
+ if (RT_SUCCESS(rc))
+ {
+ uint64_t cbFile;
+
+ rc = vdIfIoIntFileGetSize(pIfIo, pStorage, &cbFile);
+ if ( RT_SUCCESS(rc)
+ && cbFile >= sizeof(VHDFooter))
+ {
+ VHDFooter vhdFooter;
+
+ rc = vdIfIoIntFileReadSync(pIfIo, pStorage, cbFile - sizeof(VHDFooter),
+ &vhdFooter, sizeof(VHDFooter));
+ if (RT_SUCCESS(rc))
+ {
+ if (memcmp(vhdFooter.Cookie, VHD_FOOTER_COOKIE, VHD_FOOTER_COOKIE_SIZE) != 0)
+ {
+ /*
+ * There is also a backup header at the beginning in case the image got corrupted.
+ * Such corrupted images are detected here to let the open handler repair it later.
+ */
+ rc = vdIfIoIntFileReadSync(pIfIo, pStorage, 0, &vhdFooter, sizeof(VHDFooter));
+ if ( RT_FAILURE(rc)
+ || (memcmp(vhdFooter.Cookie, VHD_FOOTER_COOKIE, VHD_FOOTER_COOKIE_SIZE) != 0))
+ rc = VERR_VD_VHD_INVALID_HEADER;
+ }
+
+ if (RT_SUCCESS(rc))
+ *penmType = VDTYPE_HDD;
+ }
+ else
+ rc = VERR_VD_VHD_INVALID_HEADER;
+ }
+ else if (RT_SUCCESS(rc))
+ rc = VERR_VD_VHD_INVALID_HEADER;
+
+ vdIfIoIntFileClose(pIfIo, pStorage);
+ }
+
+ LogFlowFunc(("returns %Rrc\n", rc));
+ return rc;
+}
+
+/** @interface_method_impl{VDIMAGEBACKEND,pfnOpen} */
+static DECLCALLBACK(int) vhdOpen(const char *pszFilename, unsigned uOpenFlags,
+ PVDINTERFACE pVDIfsDisk, PVDINTERFACE pVDIfsImage,
+ VDTYPE enmType, void **ppBackendData)
+{
+ RT_NOREF1(enmType); /**< @todo r=klaus make use of the type info. */
+
+ LogFlowFunc(("pszFilename=\"%s\" uOpenFlags=%#x pVDIfsDisk=%#p pVDIfsImage=%#p enmType=%u ppBackendData=%#p\n",
+ pszFilename, uOpenFlags, pVDIfsDisk, pVDIfsImage, enmType, ppBackendData));
+ int rc = VINF_SUCCESS;
+
+ /* Check open flags. All valid flags are supported. */
+ AssertReturn(!(uOpenFlags & ~VD_OPEN_FLAGS_MASK), VERR_INVALID_PARAMETER);
+ AssertPtrReturn(pszFilename, VERR_INVALID_POINTER);
+ AssertReturn(*pszFilename != '\0', VERR_INVALID_PARAMETER);
+
+
+ PVHDIMAGE pImage = (PVHDIMAGE)RTMemAllocZ(RT_UOFFSETOF(VHDIMAGE, RegionList.aRegions[1]));
+ if (RT_LIKELY(pImage))
+ {
+ pImage->pszFilename = pszFilename;
+ pImage->pStorage = NULL;
+ pImage->pVDIfsDisk = pVDIfsDisk;
+ pImage->pVDIfsImage = pVDIfsImage;
+
+ rc = vhdOpenImage(pImage, uOpenFlags);
+ if (RT_SUCCESS(rc))
+ *ppBackendData = pImage;
+ else
+ RTMemFree(pImage);
+ }
+ else
+ rc = VERR_NO_MEMORY;
+
+ LogFlowFunc(("returns %Rrc (pBackendData=%#p)\n", rc, *ppBackendData));
+ return rc;
+}
+
+/** @interface_method_impl{VDIMAGEBACKEND,pfnCreate} */
+static DECLCALLBACK(int) vhdCreate(const char *pszFilename, uint64_t cbSize,
+ unsigned uImageFlags, const char *pszComment,
+ PCVDGEOMETRY pPCHSGeometry, PCVDGEOMETRY pLCHSGeometry,
+ PCRTUUID pUuid, unsigned uOpenFlags,
+ unsigned uPercentStart, unsigned uPercentSpan,
+ PVDINTERFACE pVDIfsDisk, PVDINTERFACE pVDIfsImage,
+ PVDINTERFACE pVDIfsOperation, VDTYPE enmType,
+ void **ppBackendData)
+{
+ LogFlowFunc(("pszFilename=\"%s\" cbSize=%llu uImageFlags=%#x pszComment=\"%s\" pPCHSGeometry=%#p pLCHSGeometry=%#p Uuid=%RTuuid uOpenFlags=%#x uPercentStart=%u uPercentSpan=%u pVDIfsDisk=%#p pVDIfsImage=%#p pVDIfsOperation=%#p enmType=%u ppBackendData=%#p",
+ pszFilename, cbSize, uImageFlags, pszComment, pPCHSGeometry, pLCHSGeometry, pUuid, uOpenFlags, uPercentStart, uPercentSpan, pVDIfsDisk, pVDIfsImage, pVDIfsOperation, enmType, ppBackendData));
+ int rc;
+ PVDINTERFACEPROGRESS pIfProgress = VDIfProgressGet(pVDIfsOperation);
+
+ /* Check the VD container type. */
+ if (enmType != VDTYPE_HDD)
+ return VERR_VD_INVALID_TYPE;
+
+ /* Check open flags. All valid flags are supported. */
+ AssertReturn(!(uOpenFlags & ~VD_OPEN_FLAGS_MASK), VERR_INVALID_PARAMETER);
+ AssertPtrReturn(pszFilename, VERR_INVALID_POINTER);
+ AssertReturn(*pszFilename != '\0', VERR_INVALID_PARAMETER);
+ AssertPtrReturn(pPCHSGeometry, VERR_INVALID_POINTER);
+ AssertPtrReturn(pLCHSGeometry, VERR_INVALID_POINTER);
+ /** @todo Check the values of other params */
+
+ PVHDIMAGE pImage = (PVHDIMAGE)RTMemAllocZ(RT_UOFFSETOF(VHDIMAGE, RegionList.aRegions[1]));
+ if (RT_LIKELY(pImage))
+ {
+ pImage->pszFilename = pszFilename;
+ pImage->pStorage = NULL;
+ pImage->pVDIfsDisk = pVDIfsDisk;
+ pImage->pVDIfsImage = pVDIfsImage;
+
+ /* Get I/O interface. */
+ pImage->pIfIo = VDIfIoIntGet(pImage->pVDIfsImage);
+ if (RT_LIKELY(RT_VALID_PTR(pImage->pIfIo)))
+ {
+ rc = vhdCreateImage(pImage, cbSize, uImageFlags, pszComment,
+ pPCHSGeometry, pLCHSGeometry, pUuid, uOpenFlags,
+ pIfProgress, uPercentStart, uPercentSpan);
+ if (RT_SUCCESS(rc))
+ {
+ /* So far the image is opened in read/write mode. Make sure the
+ * image is opened in read-only mode if the caller requested that. */
+ if (uOpenFlags & VD_OPEN_FLAGS_READONLY)
+ {
+ vhdFreeImage(pImage, false);
+ rc = vhdOpenImage(pImage, uOpenFlags);
+ }
+
+ if (RT_SUCCESS(rc))
+ *ppBackendData = pImage;
+ }
+ }
+ else
+ rc = VERR_INVALID_PARAMETER;
+
+ if (RT_FAILURE(rc))
+ RTMemFree(pImage);
+ }
+ else
+ rc = VERR_NO_MEMORY;
+
+ LogFlowFunc(("returns %Rrc\n", rc));
+ return rc;
+}
+
+/** @interface_method_impl{VDIMAGEBACKEND,pfnRename} */
+static DECLCALLBACK(int) vhdRename(void *pBackendData, const char *pszFilename)
+{
+ LogFlowFunc(("pBackendData=%#p pszFilename=%#p\n", pBackendData, pszFilename));
+ int rc = VINF_SUCCESS;
+ PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
+
+ /* Check arguments. */
+ AssertReturn((pImage && pszFilename && *pszFilename), VERR_INVALID_PARAMETER);
+
+ /* Close the image. */
+ rc = vhdFreeImage(pImage, false);
+ if (RT_SUCCESS(rc))
+ {
+ /* Rename the file. */
+ rc = vdIfIoIntFileMove(pImage->pIfIo, pImage->pszFilename, pszFilename, 0);
+ if (RT_SUCCESS(rc))
+ {
+ /* Update pImage with the new information. */
+ pImage->pszFilename = pszFilename;
+
+ /* Open the old file with new name. */
+ rc = vhdOpenImage(pImage, pImage->uOpenFlags);
+ }
+ else
+ {
+ /* The move failed, try to reopen the original image. */
+ int rc2 = vhdOpenImage(pImage, pImage->uOpenFlags);
+ if (RT_FAILURE(rc2))
+ rc = rc2;
+ }
+ }
+
+ LogFlowFunc(("returns %Rrc\n", rc));
+ return rc;
+}
+
+/** @interface_method_impl{VDIMAGEBACKEND,pfnClose} */
+static DECLCALLBACK(int) vhdClose(void *pBackendData, bool fDelete)
+{
+ LogFlowFunc(("pBackendData=%#p fDelete=%d\n", pBackendData, fDelete));
+ PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
+
+ int rc = vhdFreeImage(pImage, fDelete);
+ RTMemFree(pImage);
+
+ LogFlowFunc(("returns %Rrc\n", rc));
+ return rc;
+}
+
+/** @interface_method_impl{VDIMAGEBACKEND,pfnRead} */
+static DECLCALLBACK(int) vhdRead(void *pBackendData, uint64_t uOffset, size_t cbToRead,
+ PVDIOCTX pIoCtx, size_t *pcbActuallyRead)
+{
+ PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
+ int rc = VINF_SUCCESS;
+
+ LogFlowFunc(("pBackendData=%p uOffset=%#llx pIoCtx=%#p cbToRead=%u pcbActuallyRead=%p\n",
+ pBackendData, uOffset, pIoCtx, cbToRead, pcbActuallyRead));
+
+ AssertPtr(pImage);
+ Assert(uOffset % 512 == 0);
+ Assert(cbToRead % 512 == 0);
+ AssertPtrReturn(pIoCtx, VERR_INVALID_POINTER);
+ AssertReturn(cbToRead, VERR_INVALID_PARAMETER);
+ AssertReturn(uOffset + cbToRead <= pImage->cbSize, VERR_INVALID_PARAMETER);
+
+ /*
+ * If we have a dynamic disk image, we need to find the data block and sector to read.
+ */
+ if (pImage->pBlockAllocationTable)
+ {
+ /*
+ * Get the data block first.
+ */
+ uint32_t cBlockAllocationTableEntry = (uOffset / VHD_SECTOR_SIZE) / pImage->cSectorsPerDataBlock;
+ uint32_t cBATEntryIndex = (uOffset / VHD_SECTOR_SIZE) % pImage->cSectorsPerDataBlock;
+ uint64_t uVhdOffset;
+
+ LogFlowFunc(("cBlockAllocationTableEntry=%u cBatEntryIndex=%u\n", cBlockAllocationTableEntry, cBATEntryIndex));
+ LogFlowFunc(("BlockAllocationEntry=%u\n", pImage->pBlockAllocationTable[cBlockAllocationTableEntry]));
+
+ /*
+ * Clip read range to remain in this data block.
+ */
+ cbToRead = RT_MIN(cbToRead, (pImage->cbDataBlock - (cBATEntryIndex * VHD_SECTOR_SIZE)));
+
+ /*
+ * If the block is not allocated the content of the entry is ~0
+ */
+ if (pImage->pBlockAllocationTable[cBlockAllocationTableEntry] == ~0U)
+ rc = VERR_VD_BLOCK_FREE;
+ else
+ {
+ uVhdOffset = ((uint64_t)pImage->pBlockAllocationTable[cBlockAllocationTableEntry] + pImage->cDataBlockBitmapSectors + cBATEntryIndex) * VHD_SECTOR_SIZE;
+ LogFlowFunc(("uVhdOffset=%llu cbToRead=%u\n", uVhdOffset, cbToRead));
+
+ /* Read in the block's bitmap. */
+ PVDMETAXFER pMetaXfer;
+ rc = vdIfIoIntFileReadMeta(pImage->pIfIo, pImage->pStorage,
+ ((uint64_t)pImage->pBlockAllocationTable[cBlockAllocationTableEntry]) * VHD_SECTOR_SIZE,
+ pImage->pu8Bitmap, pImage->cbDataBlockBitmap,
+ pIoCtx, &pMetaXfer, NULL, NULL);
+
+ if (RT_SUCCESS(rc))
+ {
+ uint32_t cSectors = 0;
+
+ vdIfIoIntMetaXferRelease(pImage->pIfIo, pMetaXfer);
+ if (vhdBlockBitmapSectorContainsData(pImage, cBATEntryIndex))
+ {
+ cBATEntryIndex++;
+ cSectors = 1;
+
+ /*
+ * The first sector being read is marked dirty, read as much as we
+ * can from child. Note that only sectors that are marked dirty
+ * must be read from child.
+ */
+ while ( (cSectors < (cbToRead / VHD_SECTOR_SIZE))
+ && vhdBlockBitmapSectorContainsData(pImage, cBATEntryIndex))
+ {
+ cBATEntryIndex++;
+ cSectors++;
+ }
+
+ cbToRead = cSectors * VHD_SECTOR_SIZE;
+
+ LogFlowFunc(("uVhdOffset=%llu cbToRead=%u\n", uVhdOffset, cbToRead));
+ rc = vdIfIoIntFileReadUser(pImage->pIfIo, pImage->pStorage,
+ uVhdOffset, pIoCtx, cbToRead);
+ }
+ else
+ {
+ /*
+ * The first sector being read is marked clean, so we should read from
+ * our parent instead, but only as much as there are the following
+ * clean sectors, because the block may still contain dirty sectors
+ * further on. We just need to compute the number of clean sectors
+ * and pass it to our caller along with the notification that they
+ * should be read from the parent.
+ */
+ cBATEntryIndex++;
+ cSectors = 1;
+
+ while ( (cSectors < (cbToRead / VHD_SECTOR_SIZE))
+ && !vhdBlockBitmapSectorContainsData(pImage, cBATEntryIndex))
+ {
+ cBATEntryIndex++;
+ cSectors++;
+ }
+
+ cbToRead = cSectors * VHD_SECTOR_SIZE;
+ LogFunc(("Sectors free: uVhdOffset=%llu cbToRead=%u\n", uVhdOffset, cbToRead));
+ rc = VERR_VD_BLOCK_FREE;
+ }
+ }
+ else
+ AssertMsg(rc == VERR_VD_NOT_ENOUGH_METADATA, ("Reading block bitmap failed rc=%Rrc\n", rc));
+ }
+ }
+ else
+ rc = vdIfIoIntFileReadUser(pImage->pIfIo, pImage->pStorage, uOffset, pIoCtx, cbToRead);
+
+ if (pcbActuallyRead)
+ *pcbActuallyRead = cbToRead;
+
+ LogFlowFunc(("returns rc=%Rrc\n", rc));
+ return rc;
+}
+
+/** @interface_method_impl{VDIMAGEBACKEND,pfnWrite} */
+static DECLCALLBACK(int) vhdWrite(void *pBackendData, uint64_t uOffset, size_t cbToWrite,
+ PVDIOCTX pIoCtx, size_t *pcbWriteProcess, size_t *pcbPreRead,
+ size_t *pcbPostRead, unsigned fWrite)
+{
+ PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
+ int rc = VINF_SUCCESS;
+
+ LogFlowFunc(("pBackendData=%p uOffset=%llu pIoCtx=%#p cbToWrite=%u pcbWriteProcess=%p pcbPreRead=%p pcbPostRead=%p fWrite=%u\n",
+ pBackendData, uOffset, pIoCtx, cbToWrite, pcbWriteProcess, pcbPreRead, pcbPostRead, fWrite));
+
+ AssertPtr(pImage);
+ Assert(!(uOffset % VHD_SECTOR_SIZE));
+ Assert(!(cbToWrite % VHD_SECTOR_SIZE));
+ AssertPtrReturn(pIoCtx, VERR_INVALID_POINTER);
+ AssertReturn(cbToWrite, VERR_INVALID_PARAMETER);
+ AssertReturn(uOffset + cbToWrite <= RT_ALIGN_64(pImage->cbSize, pImage->cbDataBlock), VERR_INVALID_PARAMETER); /* The image size might not be on a data block size boundary. */
+
+ if (pImage->pBlockAllocationTable)
+ {
+ /*
+ * Get the data block first.
+ */
+ uint32_t cSector = uOffset / VHD_SECTOR_SIZE;
+ uint32_t cBlockAllocationTableEntry = cSector / pImage->cSectorsPerDataBlock;
+ uint32_t cBATEntryIndex = cSector % pImage->cSectorsPerDataBlock;
+ uint64_t uVhdOffset;
+
+ /*
+ * Clip write range.
+ */
+ cbToWrite = RT_MIN(cbToWrite, (pImage->cbDataBlock - (cBATEntryIndex * VHD_SECTOR_SIZE)));
+
+ /*
+ * If the block is not allocated the content of the entry is ~0
+ * and we need to allocate a new block. Note that while blocks are
+ * allocated with a relatively big granularity, each sector has its
+ * own bitmap entry, indicating whether it has been written or not.
+ * So that means for the purposes of the higher level that the
+ * granularity is invisible. This means there's no need to return
+ * VERR_VD_BLOCK_FREE unless the block hasn't been allocated yet.
+ */
+ if (pImage->pBlockAllocationTable[cBlockAllocationTableEntry] == ~0U)
+ {
+ /* Check if the block allocation should be suppressed. */
+ if ( (fWrite & VD_WRITE_NO_ALLOC)
+ || (cbToWrite != pImage->cbDataBlock))
+ {
+ *pcbPreRead = cBATEntryIndex * VHD_SECTOR_SIZE;
+ *pcbPostRead = pImage->cSectorsPerDataBlock * VHD_SECTOR_SIZE - cbToWrite - *pcbPreRead;
+
+ if (pcbWriteProcess)
+ *pcbWriteProcess = cbToWrite;
+ return VERR_VD_BLOCK_FREE;
+ }
+
+ PVHDIMAGEEXPAND pExpand;
+ pExpand = (PVHDIMAGEEXPAND)RTMemAllocZ(RT_UOFFSETOF_DYN(VHDIMAGEEXPAND,
+ au8Bitmap[pImage->cDataBlockBitmapSectors * VHD_SECTOR_SIZE]));
+ bool fIoInProgress = false;
+
+ if (!pExpand)
+ return VERR_NO_MEMORY;
+
+ pExpand->cbEofOld = pImage->uCurrentEndOfFile;
+ pExpand->idxBatAllocated = cBlockAllocationTableEntry;
+ pExpand->idxBlockBe = RT_H2BE_U32(pImage->uCurrentEndOfFile / VHD_SECTOR_SIZE);
+
+ /* Set the bits for all sectors having been written. */
+ for (uint32_t iSector = 0; iSector < (cbToWrite / VHD_SECTOR_SIZE); iSector++)
+ {
+ /* No need to check for a changed value because this is an initial write. */
+ vhdBlockBitmapSectorSet(pImage, pExpand->au8Bitmap, cBATEntryIndex);
+ cBATEntryIndex++;
+ }
+
+ do
+ {
+ /*
+ * Start with the sector bitmap.
+ */
+ rc = vdIfIoIntFileWriteMeta(pImage->pIfIo, pImage->pStorage,
+ pImage->uCurrentEndOfFile,
+ pExpand->au8Bitmap,
+ pImage->cDataBlockBitmapSectors * VHD_SECTOR_SIZE, pIoCtx,
+ vhdAsyncExpansionDataBlockBitmapComplete,
+ pExpand);
+ if (RT_SUCCESS(rc))
+ VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_BLOCKBITMAP_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_SUCCESS);
+ else if (rc == VERR_VD_ASYNC_IO_IN_PROGRESS)
+ fIoInProgress = true;
+ else
+ {
+ VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_BLOCKBITMAP_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_FAILED);
+ VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_USERBLOCK_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_FAILED);
+ VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_BAT_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_FAILED);
+ VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_FOOTER_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_FAILED);
+ break;
+ }
+
+
+ /*
+ * Write the new block at the current end of the file.
+ */
+ rc = vdIfIoIntFileWriteUser(pImage->pIfIo, pImage->pStorage,
+ pImage->uCurrentEndOfFile + (pImage->cDataBlockBitmapSectors + (cSector % pImage->cSectorsPerDataBlock)) * VHD_SECTOR_SIZE,
+ pIoCtx, cbToWrite,
+ vhdAsyncExpansionDataComplete,
+ pExpand);
+ if (RT_SUCCESS(rc))
+ VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_USERBLOCK_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_SUCCESS);
+ else if (rc == VERR_VD_ASYNC_IO_IN_PROGRESS)
+ fIoInProgress = true;
+ else
+ {
+ VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_USERBLOCK_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_FAILED);
+ VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_BAT_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_FAILED);
+ VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_FOOTER_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_FAILED);
+ break;
+ }
+
+ /*
+ * Write entry in the BAT.
+ */
+ rc = vdIfIoIntFileWriteMeta(pImage->pIfIo, pImage->pStorage,
+ pImage->uBlockAllocationTableOffset + cBlockAllocationTableEntry * sizeof(uint32_t),
+ &pExpand->idxBlockBe, sizeof(uint32_t), pIoCtx,
+ vhdAsyncExpansionBatUpdateComplete,
+ pExpand);
+ if (RT_SUCCESS(rc))
+ VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_BAT_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_SUCCESS);
+ else if (rc == VERR_VD_ASYNC_IO_IN_PROGRESS)
+ fIoInProgress = true;
+ else
+ {
+ VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_BAT_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_FAILED);
+ VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_FOOTER_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_FAILED);
+ break;
+ }
+
+ /*
+ * Set the new end of the file and link the new block into the BAT.
+ */
+ pImage->uCurrentEndOfFile += pImage->cDataBlockBitmapSectors * VHD_SECTOR_SIZE + pImage->cbDataBlock;
+
+ /* Update the footer. */
+ rc = vdIfIoIntFileWriteMeta(pImage->pIfIo, pImage->pStorage,
+ pImage->uCurrentEndOfFile,
+ &pImage->vhdFooterCopy,
+ sizeof(VHDFooter), pIoCtx,
+ vhdAsyncExpansionFooterUpdateComplete,
+ pExpand);
+ if (RT_SUCCESS(rc))
+ VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_FOOTER_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_SUCCESS);
+ else if (rc == VERR_VD_ASYNC_IO_IN_PROGRESS)
+ fIoInProgress = true;
+ else
+ {
+ VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_FOOTER_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_FAILED);
+ break;
+ }
+
+ } while (0);
+
+ if (!fIoInProgress)
+ vhdAsyncExpansionComplete(pImage, pIoCtx, pExpand);
+ else
+ rc = VERR_VD_ASYNC_IO_IN_PROGRESS;
+ }
+ else
+ {
+ /*
+ * Calculate the real offset in the file.
+ */
+ uVhdOffset = ((uint64_t)pImage->pBlockAllocationTable[cBlockAllocationTableEntry] + pImage->cDataBlockBitmapSectors + cBATEntryIndex) * VHD_SECTOR_SIZE;
+
+ /* Read in the block's bitmap. */
+ PVDMETAXFER pMetaXfer;
+ rc = vdIfIoIntFileReadMeta(pImage->pIfIo, pImage->pStorage,
+ ((uint64_t)pImage->pBlockAllocationTable[cBlockAllocationTableEntry]) * VHD_SECTOR_SIZE,
+ pImage->pu8Bitmap,
+ pImage->cbDataBlockBitmap, pIoCtx,
+ &pMetaXfer, NULL, NULL);
+ if (RT_SUCCESS(rc))
+ {
+ vdIfIoIntMetaXferRelease(pImage->pIfIo, pMetaXfer);
+
+ /* Write data. */
+ rc = vdIfIoIntFileWriteUser(pImage->pIfIo, pImage->pStorage,
+ uVhdOffset, pIoCtx, cbToWrite,
+ NULL, NULL);
+ if (RT_SUCCESS(rc) || rc == VERR_VD_ASYNC_IO_IN_PROGRESS)
+ {
+ bool fChanged = false;
+
+ /* Set the bits for all sectors having been written. */
+ for (uint32_t iSector = 0; iSector < (cbToWrite / VHD_SECTOR_SIZE); iSector++)
+ {
+ fChanged |= vhdBlockBitmapSectorSet(pImage, pImage->pu8Bitmap, cBATEntryIndex);
+ cBATEntryIndex++;
+ }
+
+ /* Only write the bitmap if it was changed. */
+ if (fChanged)
+ {
+ /*
+ * Write the bitmap back.
+ *
+ * @note We don't have a completion callback here because we
+ * can't do anything if the write fails for some reason.
+ * The error will propagated to the device/guest
+ * by the generic VD layer already and we don't need
+ * to rollback anything here.
+ */
+ rc = vdIfIoIntFileWriteMeta(pImage->pIfIo, pImage->pStorage,
+ ((uint64_t)pImage->pBlockAllocationTable[cBlockAllocationTableEntry]) * VHD_SECTOR_SIZE,
+ pImage->pu8Bitmap,
+ pImage->cbDataBlockBitmap,
+ pIoCtx, NULL, NULL);
+ }
+ }
+ }
+ }
+ }
+ else
+ rc = vdIfIoIntFileWriteUser(pImage->pIfIo, pImage->pStorage,
+ uOffset, pIoCtx, cbToWrite, NULL, NULL);
+
+ if (pcbWriteProcess)
+ *pcbWriteProcess = cbToWrite;
+
+ /* Stay on the safe side. Do not run the risk of confusing the higher
+ * level, as that can be pretty lethal to image consistency. */
+ *pcbPreRead = 0;
+ *pcbPostRead = 0;
+
+ return rc;
+}
+
+/** @interface_method_impl{VDIMAGEBACKEND,pfnFlush} */
+static DECLCALLBACK(int) vhdFlush(void *pBackendData, PVDIOCTX pIoCtx)
+{
+ LogFlowFunc(("pBackendData=%#p\n", pBackendData));
+ PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
+
+ /* No need to write anything here. Data is always updated on a write. */
+ int rc = vdIfIoIntFileFlush(pImage->pIfIo, pImage->pStorage, pIoCtx, NULL, NULL);
+ LogFlowFunc(("returns %Rrc\n", rc));
+ return rc;
+}
+
+/** @interface_method_impl{VDIMAGEBACKEND,pfnGetVersion} */
+static DECLCALLBACK(unsigned) vhdGetVersion(void *pBackendData)
+{
+ LogFlowFunc(("pBackendData=%#p\n", pBackendData));
+ PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
+
+ AssertPtrReturn(pImage, 0);
+
+ unsigned uVersion = 1; /**< @todo use correct version */
+
+ LogFlowFunc(("returns %u\n", uVersion));
+ return uVersion;
+}
+
+/** @interface_method_impl{VDIMAGEBACKEND,pfnGetFileSize} */
+static DECLCALLBACK(uint64_t) vhdGetFileSize(void *pBackendData)
+{
+ LogFlowFunc(("pBackendData=%#p\n", pBackendData));
+ PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
+ uint64_t cb = 0;
+
+ AssertPtrReturn(pImage, 0);
+
+ if (pImage->pStorage)
+ cb = pImage->uCurrentEndOfFile + sizeof(VHDFooter);
+
+ LogFlowFunc(("returns %lld\n", cb));
+ return cb;
+}
+
+/** @interface_method_impl{VDIMAGEBACKEND,pfnGetPCHSGeometry} */
+static DECLCALLBACK(int) vhdGetPCHSGeometry(void *pBackendData, PVDGEOMETRY pPCHSGeometry)
+{
+ LogFlowFunc(("pBackendData=%#p pPCHSGeometry=%#p\n", pBackendData, pPCHSGeometry));
+ PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
+ int rc = VINF_SUCCESS;
+
+ AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
+
+ if (pImage->PCHSGeometry.cCylinders)
+ *pPCHSGeometry = pImage->PCHSGeometry;
+ else
+ rc = VERR_VD_GEOMETRY_NOT_SET;
+
+ LogFlowFunc(("returns %Rrc (CHS=%u/%u/%u)\n", rc, pImage->PCHSGeometry.cCylinders,
+ pImage->PCHSGeometry.cHeads, pImage->PCHSGeometry.cSectors));
+ return rc;
+}
+
+/** @interface_method_impl{VDIMAGEBACKEND,pfnSetPCHSGeometry} */
+static DECLCALLBACK(int) vhdSetPCHSGeometry(void *pBackendData, PCVDGEOMETRY pPCHSGeometry)
+{
+ LogFlowFunc(("pBackendData=%#p pPCHSGeometry=%#p PCHS=%u/%u/%u\n",
+ pBackendData, pPCHSGeometry, pPCHSGeometry->cCylinders, pPCHSGeometry->cHeads, pPCHSGeometry->cSectors));
+ PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
+ int rc = VINF_SUCCESS;
+
+ AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
+
+ if (pImage->uOpenFlags & VD_OPEN_FLAGS_READONLY)
+ rc = VERR_VD_IMAGE_READ_ONLY;
+ else
+ pImage->PCHSGeometry = *pPCHSGeometry;
+
+ LogFlowFunc(("returns %Rrc\n", rc));
+ return rc;
+}
+
+/** @interface_method_impl{VDIMAGEBACKEND,pfnGetLCHSGeometry} */
+static DECLCALLBACK(int) vhdGetLCHSGeometry(void *pBackendData, PVDGEOMETRY pLCHSGeometry)
+{
+ LogFlowFunc(("pBackendData=%#p pLCHSGeometry=%#p\n", pBackendData, pLCHSGeometry));
+ PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
+ int rc = VINF_SUCCESS;
+
+ AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
+
+ if (pImage->LCHSGeometry.cCylinders)
+ *pLCHSGeometry = pImage->LCHSGeometry;
+ else
+ rc = VERR_VD_GEOMETRY_NOT_SET;
+
+ LogFlowFunc(("returns %Rrc (CHS=%u/%u/%u)\n", rc, pImage->LCHSGeometry.cCylinders,
+ pImage->LCHSGeometry.cHeads, pImage->LCHSGeometry.cSectors));
+ return rc;
+}
+
+/** @interface_method_impl{VDIMAGEBACKEND,pfnSetLCHSGeometry} */
+static DECLCALLBACK(int) vhdSetLCHSGeometry(void *pBackendData, PCVDGEOMETRY pLCHSGeometry)
+{
+ PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
+ int rc = VINF_SUCCESS;
+
+ AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
+
+ if (pImage->uOpenFlags & VD_OPEN_FLAGS_READONLY)
+ rc = VERR_VD_IMAGE_READ_ONLY;
+ else
+ pImage->LCHSGeometry = *pLCHSGeometry;
+
+ LogFlowFunc(("returns %Rrc\n", rc));
+ return rc;
+}
+
+/** @copydoc VDIMAGEBACKEND::pfnQueryRegions */
+static DECLCALLBACK(int) vhdQueryRegions(void *pBackendData, PCVDREGIONLIST *ppRegionList)
+{
+ LogFlowFunc(("pBackendData=%#p ppRegionList=%#p\n", pBackendData, ppRegionList));
+ PVHDIMAGE pThis = (PVHDIMAGE)pBackendData;
+
+ AssertPtrReturn(pThis, VERR_VD_NOT_OPENED);
+
+ *ppRegionList = &pThis->RegionList;
+ LogFlowFunc(("returns %Rrc\n", VINF_SUCCESS));
+ return VINF_SUCCESS;
+}
+
+/** @copydoc VDIMAGEBACKEND::pfnRegionListRelease */
+static DECLCALLBACK(void) vhdRegionListRelease(void *pBackendData, PCVDREGIONLIST pRegionList)
+{
+ RT_NOREF1(pRegionList);
+ LogFlowFunc(("pBackendData=%#p pRegionList=%#p\n", pBackendData, pRegionList));
+ PVHDIMAGE pThis = (PVHDIMAGE)pBackendData;
+ AssertPtr(pThis); RT_NOREF(pThis);
+
+ /* Nothing to do here. */
+}
+
+/** @interface_method_impl{VDIMAGEBACKEND,pfnGetImageFlags} */
+static DECLCALLBACK(unsigned) vhdGetImageFlags(void *pBackendData)
+{
+ LogFlowFunc(("pBackendData=%#p\n", pBackendData));
+ PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
+
+ AssertPtrReturn(pImage, 0);
+
+ LogFlowFunc(("returns %#x\n", pImage->uImageFlags));
+ return pImage->uImageFlags;
+}
+
+/** @interface_method_impl{VDIMAGEBACKEND,pfnGetOpenFlags} */
+static DECLCALLBACK(unsigned) vhdGetOpenFlags(void *pBackendData)
+{
+ LogFlowFunc(("pBackendData=%#p\n", pBackendData));
+ PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
+
+ AssertPtrReturn(pImage, 0);
+
+ LogFlowFunc(("returns %#x\n", pImage->uOpenFlags));
+ return pImage->uOpenFlags;
+}
+
+/** @interface_method_impl{VDIMAGEBACKEND,pfnSetOpenFlags} */
+static DECLCALLBACK(int) vhdSetOpenFlags(void *pBackendData, unsigned uOpenFlags)
+{
+ LogFlowFunc(("pBackendData=%#p\n uOpenFlags=%#x", pBackendData, uOpenFlags));
+ PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
+ int rc = VINF_SUCCESS;
+
+ /* Image must be opened and the new flags must be valid. */
+ if (!pImage || (uOpenFlags & ~( VD_OPEN_FLAGS_READONLY | VD_OPEN_FLAGS_INFO
+ | VD_OPEN_FLAGS_ASYNC_IO | VD_OPEN_FLAGS_SHAREABLE
+ | VD_OPEN_FLAGS_SEQUENTIAL | VD_OPEN_FLAGS_SKIP_CONSISTENCY_CHECKS)))
+ rc = VERR_INVALID_PARAMETER;
+ else
+ {
+ /* Implement this operation via reopening the image. */
+ rc = vhdFreeImage(pImage, false);
+ if (RT_SUCCESS(rc))
+ rc = vhdOpenImage(pImage, uOpenFlags);
+ }
+
+ LogFlowFunc(("returns %Rrc\n", rc));
+ return rc;
+}
+
+/** @interface_method_impl{VDIMAGEBACKEND,pfnGetComment} */
+static DECLCALLBACK(int) vhdGetComment(void *pBackendData, char *pszComment,
+ size_t cbComment)
+{
+ RT_NOREF2(pszComment, cbComment);
+ LogFlowFunc(("pBackendData=%#p pszComment=%#p cbComment=%zu\n", pBackendData, pszComment, cbComment));
+ PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
+
+ AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
+
+ LogFlowFunc(("returns %Rrc comment='%s'\n", VERR_NOT_SUPPORTED, pszComment));
+ return VERR_NOT_SUPPORTED;
+}
+
+/** @interface_method_impl{VDIMAGEBACKEND,pfnSetComment} */
+static DECLCALLBACK(int) vhdSetComment(void *pBackendData, const char *pszComment)
+{
+ RT_NOREF1(pszComment);
+ LogFlowFunc(("pBackendData=%#p pszComment=\"%s\"\n", pBackendData, pszComment));
+ PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
+
+ AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
+
+ int rc;
+ if (pImage->uOpenFlags & VD_OPEN_FLAGS_READONLY)
+ rc = VERR_VD_IMAGE_READ_ONLY;
+ else
+ rc = VERR_NOT_SUPPORTED;
+
+ LogFlowFunc(("returns %Rrc\n", rc));
+ return rc;
+}
+
+/** @interface_method_impl{VDIMAGEBACKEND,pfnGetUuid} */
+static DECLCALLBACK(int) vhdGetUuid(void *pBackendData, PRTUUID pUuid)
+{
+ LogFlowFunc(("pBackendData=%#p pUuid=%#p\n", pBackendData, pUuid));
+ PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
+
+ AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
+
+ *pUuid = pImage->ImageUuid;
+
+ LogFlowFunc(("returns %Rrc (%RTuuid)\n", VINF_SUCCESS, pUuid));
+ return VINF_SUCCESS;
+}
+
+/** @interface_method_impl{VDIMAGEBACKEND,pfnSetUuid} */
+static DECLCALLBACK(int) vhdSetUuid(void *pBackendData, PCRTUUID pUuid)
+{
+ LogFlowFunc(("pBackendData=%#p Uuid=%RTuuid\n", pBackendData, pUuid));
+ PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
+ int rc = VINF_SUCCESS;
+
+ AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
+
+ if (!(pImage->uOpenFlags & VD_OPEN_FLAGS_READONLY))
+ {
+ pImage->ImageUuid = *pUuid;
+ /* Update the footer copy. It will get written to disk when the image is closed. */
+ memcpy(&pImage->vhdFooterCopy.UniqueID, pUuid, 16);
+ /* Update checksum. */
+ pImage->vhdFooterCopy.Checksum = 0;
+ pImage->vhdFooterCopy.Checksum = RT_H2BE_U32(vhdChecksum(&pImage->vhdFooterCopy, sizeof(VHDFooter)));
+
+ /* Need to update the dynamic disk header to update the disk footer copy at the beginning. */
+ if (!(pImage->uImageFlags & VD_IMAGE_FLAGS_FIXED))
+ pImage->fDynHdrNeedsUpdate = true;
+ }
+ else
+ rc = VERR_VD_IMAGE_READ_ONLY;
+
+ LogFlowFunc(("returns %Rrc\n", rc));
+ return rc;
+}
+
+/** @interface_method_impl{VDIMAGEBACKEND,pfnGetModificationUuid} */
+static DECLCALLBACK(int) vhdGetModificationUuid(void *pBackendData, PRTUUID pUuid)
+{
+ RT_NOREF1(pUuid);
+ LogFlowFunc(("pBackendData=%#p pUuid=%#p\n", pBackendData, pUuid));
+ PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
+
+ AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
+
+ LogFlowFunc(("returns %Rrc (%RTuuid)\n", VERR_NOT_SUPPORTED, pUuid));
+ return VERR_NOT_SUPPORTED;
+}
+
+/** @interface_method_impl{VDIMAGEBACKEND,pfnSetModificationUuid} */
+static DECLCALLBACK(int) vhdSetModificationUuid(void *pBackendData, PCRTUUID pUuid)
+{
+ RT_NOREF1(pUuid);
+ LogFlowFunc(("pBackendData=%#p Uuid=%RTuuid\n", pBackendData, pUuid));
+ PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
+
+ AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
+
+ int rc;
+ if (pImage->uOpenFlags & VD_OPEN_FLAGS_READONLY)
+ rc = VERR_VD_IMAGE_READ_ONLY;
+ else
+ rc = VERR_NOT_SUPPORTED;
+
+ LogFlowFunc(("returns %Rrc\n", rc));
+ return rc;
+}
+
+/** @interface_method_impl{VDIMAGEBACKEND,pfnGetParentUuid} */
+static DECLCALLBACK(int) vhdGetParentUuid(void *pBackendData, PRTUUID pUuid)
+{
+ LogFlowFunc(("pBackendData=%#p pUuid=%#p\n", pBackendData, pUuid));
+ PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
+
+ AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
+
+ *pUuid = pImage->ParentUuid;
+
+ LogFlowFunc(("returns %Rrc (%RTuuid)\n", VINF_SUCCESS, pUuid));
+ return VINF_SUCCESS;
+}
+
+/** @interface_method_impl{VDIMAGEBACKEND,pfnSetParentUuid} */
+static DECLCALLBACK(int) vhdSetParentUuid(void *pBackendData, PCRTUUID pUuid)
+{
+ LogFlowFunc(("pBackendData=%#p Uuid=%RTuuid\n", pBackendData, pUuid));
+ PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
+ int rc = VINF_SUCCESS;
+
+ if (pImage && pImage->pStorage)
+ {
+ if (!(pImage->uImageFlags & VD_IMAGE_FLAGS_FIXED))
+ {
+ pImage->ParentUuid = *pUuid;
+ pImage->fDynHdrNeedsUpdate = true;
+ }
+ else
+ rc = VERR_VD_IMAGE_READ_ONLY;
+ }
+ else
+ rc = VERR_VD_NOT_OPENED;
+
+ LogFlowFunc(("returns %Rrc\n", rc));
+ return rc;
+}
+
+/** @interface_method_impl{VDIMAGEBACKEND,pfnGetParentModificationUuid} */
+static DECLCALLBACK(int) vhdGetParentModificationUuid(void *pBackendData, PRTUUID pUuid)
+{
+ RT_NOREF1(pUuid);
+ LogFlowFunc(("pBackendData=%#p pUuid=%#p\n", pBackendData, pUuid));
+ PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
+
+ AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
+
+ LogFlowFunc(("returns %Rrc (%RTuuid)\n", VERR_NOT_SUPPORTED, pUuid));
+ return VERR_NOT_SUPPORTED;
+}
+
+/** @interface_method_impl{VDIMAGEBACKEND,pfnSetParentModificationUuid} */
+static DECLCALLBACK(int) vhdSetParentModificationUuid(void *pBackendData, PCRTUUID pUuid)
+{
+ RT_NOREF1(pUuid);
+ LogFlowFunc(("pBackendData=%#p Uuid=%RTuuid\n", pBackendData, pUuid));
+ PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
+
+ AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
+
+ int rc;
+ if (pImage->uOpenFlags & VD_OPEN_FLAGS_READONLY)
+ rc = VERR_VD_IMAGE_READ_ONLY;
+ else
+ rc = VERR_NOT_SUPPORTED;
+
+ LogFlowFunc(("returns %Rrc\n", rc));
+ return rc;
+}
+
+/** @interface_method_impl{VDIMAGEBACKEND,pfnDump} */
+static DECLCALLBACK(void) vhdDump(void *pBackendData)
+{
+ PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
+
+ AssertPtrReturnVoid(pImage);
+ vdIfErrorMessage(pImage->pIfError, "Header: Geometry PCHS=%u/%u/%u LCHS=%u/%u/%u cbSector=%u\n",
+ pImage->PCHSGeometry.cCylinders, pImage->PCHSGeometry.cHeads, pImage->PCHSGeometry.cSectors,
+ pImage->LCHSGeometry.cCylinders, pImage->LCHSGeometry.cHeads, pImage->LCHSGeometry.cSectors,
+ VHD_SECTOR_SIZE);
+ vdIfErrorMessage(pImage->pIfError, "Header: uuidCreation={%RTuuid}\n", &pImage->ImageUuid);
+ vdIfErrorMessage(pImage->pIfError, "Header: uuidParent={%RTuuid}\n", &pImage->ParentUuid);
+}
+
+/** @interface_method_impl{VDIMAGEBACKEND,pfnGetTimestamp} */
+static DECLCALLBACK(int) vhdGetTimestamp(void *pBackendData, PRTTIMESPEC pTimestamp)
+{
+ PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
+
+ AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
+
+ int rc = vdIfIoIntFileGetModificationTime(pImage->pIfIo, pImage->pszFilename, pTimestamp);
+
+ LogFlowFunc(("returns %Rrc\n", rc));
+ return rc;
+}
+
+/** @interface_method_impl{VDIMAGEBACKEND,pfnGetParentTimestamp} */
+static DECLCALLBACK(int) vhdGetParentTimestamp(void *pBackendData, PRTTIMESPEC pTimestamp)
+{
+ PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
+
+ AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
+
+ vhdTime2RtTime(pTimestamp, pImage->u32ParentTimestamp);
+ LogFlowFunc(("returns %Rrc\n", VINF_SUCCESS));
+ return VINF_SUCCESS;
+}
+
+/** @interface_method_impl{VDIMAGEBACKEND,pfnSetParentTimestamp} */
+static DECLCALLBACK(int) vhdSetParentTimestamp(void *pBackendData, PCRTTIMESPEC pTimestamp)
+{
+ int rc = VINF_SUCCESS;
+ PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
+
+ AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
+ if (pImage->uOpenFlags & VD_OPEN_FLAGS_READONLY)
+ rc = VERR_VD_IMAGE_READ_ONLY;
+ else
+ {
+ pImage->u32ParentTimestamp = vhdRtTime2VhdTime(pTimestamp);
+ pImage->fDynHdrNeedsUpdate = true;
+ }
+
+ LogFlowFunc(("returns %Rrc\n", rc));
+ return rc;
+}
+
+/** @interface_method_impl{VDIMAGEBACKEND,pfnGetParentFilename} */
+static DECLCALLBACK(int) vhdGetParentFilename(void *pBackendData, char **ppszParentFilename)
+{
+ PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
+
+ AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
+ *ppszParentFilename = RTStrDup(pImage->pszParentFilename);
+
+ LogFlowFunc(("returns %Rrc\n", VINF_SUCCESS));
+ return VINF_SUCCESS;
+}
+
+/** @interface_method_impl{VDIMAGEBACKEND,pfnSetParentFilename} */
+static DECLCALLBACK(int) vhdSetParentFilename(void *pBackendData, const char *pszParentFilename)
+{
+ int rc = VINF_SUCCESS;
+ PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
+
+ AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
+
+ if (pImage->uOpenFlags & VD_OPEN_FLAGS_READONLY)
+ rc = VERR_VD_IMAGE_READ_ONLY;
+ else
+ {
+ if (pImage->pszParentFilename)
+ RTStrFree(pImage->pszParentFilename);
+ pImage->pszParentFilename = RTStrDup(pszParentFilename);
+ if (!pImage->pszParentFilename)
+ rc = VERR_NO_MEMORY;
+ else
+ pImage->fDynHdrNeedsUpdate = true;
+ }
+
+ LogFlowFunc(("returns %Rrc\n", rc));
+ return rc;
+}
+
+/** @interface_method_impl{VDIMAGEBACKEND,pfnCompact} */
+static DECLCALLBACK(int) vhdCompact(void *pBackendData, unsigned uPercentStart,
+ unsigned uPercentSpan, PVDINTERFACE pVDIfsDisk,
+ PVDINTERFACE pVDIfsImage, PVDINTERFACE pVDIfsOperation)
+{
+ RT_NOREF2(pVDIfsDisk, pVDIfsImage);
+ PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
+ int rc = VINF_SUCCESS;
+ void *pvBuf = NULL;
+ uint32_t *paBlocks = NULL;
+ PVDINTERFACEPROGRESS pIfProgress = VDIfProgressGet(pVDIfsOperation);
+
+ PFNVDPARENTREAD pfnParentRead = NULL;
+ void *pvParent = NULL;
+ PVDINTERFACEPARENTSTATE pIfParentState = VDIfParentStateGet(pVDIfsOperation);
+ if (pIfParentState)
+ {
+ pfnParentRead = pIfParentState->pfnParentRead;
+ pvParent = pIfParentState->Core.pvUser;
+ }
+
+ do
+ {
+ AssertBreakStmt(pImage, rc = VERR_INVALID_PARAMETER);
+
+ AssertBreakStmt(!(pImage->uOpenFlags & VD_OPEN_FLAGS_READONLY),
+ rc = VERR_VD_IMAGE_READ_ONLY);
+
+ /* Reject fixed images as they don't have a BAT. */
+ if (pImage->uImageFlags & VD_IMAGE_FLAGS_FIXED)
+ {
+ rc = VERR_NOT_SUPPORTED;
+ break;
+ }
+
+ if (pfnParentRead)
+ {
+ pvParent = RTMemTmpAlloc(pImage->cbDataBlock);
+ AssertBreakStmt(pvParent, rc = VERR_NO_MEMORY);
+ }
+ pvBuf = RTMemTmpAlloc(pImage->cbDataBlock);
+ AssertBreakStmt(pvBuf, rc = VERR_NO_MEMORY);
+
+ unsigned cBlocksAllocated = 0;
+ unsigned cBlocksToMove = 0;
+ unsigned cBlocks = pImage->cBlockAllocationTableEntries;
+ uint32_t offBlocksStart = ~0U; /* Start offset of data blocks in sectors. */
+ uint32_t *paBat = pImage->pBlockAllocationTable;
+
+ /* Count the number of allocated blocks and find the start offset for the data blocks. */
+ for (unsigned i = 0; i < cBlocks; i++)
+ if (paBat[i] != ~0U)
+ {
+ cBlocksAllocated++;
+ if (paBat[i] < offBlocksStart)
+ offBlocksStart = paBat[i];
+ }
+
+ if (!cBlocksAllocated)
+ {
+ /* Nothing to do. */
+ rc = VINF_SUCCESS;
+ break;
+ }
+
+ paBlocks = (uint32_t *)RTMemTmpAllocZ(cBlocksAllocated * sizeof(uint32_t));
+ AssertBreakStmt(paBlocks, rc = VERR_NO_MEMORY);
+
+ /* Invalidate the back resolving array. */
+ for (unsigned i = 0; i < cBlocksAllocated; i++)
+ paBlocks[i] = ~0U;
+
+ /* Fill the back resolving table. */
+ for (unsigned i = 0; i < cBlocks; i++)
+ if (paBat[i] != ~0U)
+ {
+ unsigned idxBlock = (paBat[i] - offBlocksStart) / pImage->cSectorsPerDataBlock;
+ if ( idxBlock < cBlocksAllocated
+ && paBlocks[idxBlock] == ~0U)
+ paBlocks[idxBlock] = i;
+ else
+ {
+ /* The image is in an inconsistent state. Don't go further. */
+ rc = VERR_INVALID_STATE;
+ break;
+ }
+ }
+
+ if (RT_FAILURE(rc))
+ break;
+
+ /* Find redundant information and update the block pointers
+ * accordingly, creating bubbles. Keep disk up to date, as this
+ * enables cancelling. */
+ for (unsigned i = 0; i < cBlocks; i++)
+ {
+ if (paBat[i] != ~0U)
+ {
+ unsigned idxBlock = (paBat[i] - offBlocksStart) / pImage->cSectorsPerDataBlock;
+
+ /* Block present in image file, read relevant data. */
+ uint64_t u64Offset = ((uint64_t)paBat[i] + pImage->cDataBlockBitmapSectors) * VHD_SECTOR_SIZE;
+ rc = vdIfIoIntFileReadSync(pImage->pIfIo, pImage->pStorage,
+ u64Offset, pvBuf, pImage->cbDataBlock);
+ if (RT_FAILURE(rc))
+ break;
+
+ if (ASMBitFirstSet((volatile void *)pvBuf, (uint32_t)pImage->cbDataBlock * 8) == -1)
+ {
+ paBat[i] = UINT32_MAX;
+ paBlocks[idxBlock] = ~0U;
+ /* Adjust progress info, one block to be relocated. */
+ cBlocksToMove++;
+ }
+ else if (pfnParentRead)
+ {
+ rc = pfnParentRead(pvParent, (uint64_t)i * pImage->cbDataBlock, pvParent, pImage->cbDataBlock);
+ if (RT_FAILURE(rc))
+ break;
+ if (!memcmp(pvParent, pvBuf, pImage->cbDataBlock))
+ {
+ paBat[i] = ~0U;
+ paBlocks[idxBlock] = ~0U;
+ /* Adjust progress info, one block to be relocated. */
+ cBlocksToMove++;
+ }
+ }
+ }
+
+ vdIfProgress(pIfProgress, (uint64_t)i * uPercentSpan / (cBlocks + cBlocksToMove) + uPercentStart);
+ }
+
+ if (RT_SUCCESS(rc))
+ {
+ /* Fill bubbles with other data (if available). */
+ unsigned cBlocksMoved = 0;
+ unsigned uBlockUsedPos = cBlocksAllocated;
+ size_t cbBlock = pImage->cbDataBlock + pImage->cbDataBlockBitmap; /** < Size of whole block containing the bitmap and the user data. */
+
+ /* Allocate data buffer to hold the data block and allocation bitmap in front of the actual data. */
+ RTMemTmpFree(pvBuf);
+ pvBuf = RTMemTmpAllocZ(cbBlock);
+ AssertBreakStmt(pvBuf, rc = VERR_NO_MEMORY);
+
+ for (unsigned i = 0; i < cBlocksAllocated; i++)
+ {
+ unsigned uBlock = paBlocks[i];
+ if (uBlock == ~0U)
+ {
+ unsigned uBlockData = ~0U;
+ while (uBlockUsedPos > i && uBlockData == ~0U)
+ {
+ uBlockUsedPos--;
+ uBlockData = paBlocks[uBlockUsedPos];
+ }
+ /* Terminate early if there is no block which needs copying. */
+ if (uBlockUsedPos == i)
+ break;
+ uint64_t u64Offset = (uint64_t)uBlockUsedPos * cbBlock
+ + (offBlocksStart * VHD_SECTOR_SIZE);
+ rc = vdIfIoIntFileReadSync(pImage->pIfIo, pImage->pStorage,
+ u64Offset, pvBuf, cbBlock);
+ if (RT_FAILURE(rc))
+ break;
+
+ u64Offset = (uint64_t)i * cbBlock
+ + (offBlocksStart * VHD_SECTOR_SIZE);
+ rc = vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage,
+ u64Offset, pvBuf, cbBlock);
+ if (RT_FAILURE(rc))
+ break;
+
+ paBat[uBlockData] = i*(pImage->cSectorsPerDataBlock + pImage->cDataBlockBitmapSectors) + offBlocksStart;
+
+ /* Truncate the file but leave enough room for the footer to avoid
+ * races if other processes fill the whole harddisk. */
+ rc = vdIfIoIntFileSetSize(pImage->pIfIo, pImage->pStorage,
+ pImage->uCurrentEndOfFile - cbBlock + VHD_SECTOR_SIZE);
+ if (RT_FAILURE(rc))
+ break;
+
+ /* Update pointers and write footer. */
+ pImage->uCurrentEndOfFile -= cbBlock;
+
+ /* We're kinda screwed if this failes. */
+ rc = vhdUpdateFooter(pImage);
+ if (RT_FAILURE(rc))
+ break;
+
+ paBlocks[i] = uBlockData;
+ paBlocks[uBlockUsedPos] = ~0U;
+ cBlocksMoved++;
+ }
+
+ rc = vdIfProgress(pIfProgress, (uint64_t)(cBlocks + cBlocksMoved) * uPercentSpan / (cBlocks + cBlocksToMove) + uPercentStart);
+ }
+ }
+
+ /* Write the new BAT in any case. */
+ rc = vhdFlushImage(pImage);
+ } while (0);
+
+ if (paBlocks)
+ RTMemTmpFree(paBlocks);
+ if (pvParent)
+ RTMemTmpFree(pvParent);
+ if (pvBuf)
+ RTMemTmpFree(pvBuf);
+
+ if (RT_SUCCESS(rc))
+ vdIfProgress(pIfProgress, uPercentStart + uPercentSpan);
+
+ LogFlowFunc(("returns %Rrc\n", rc));
+ return rc;
+}
+
+/** @interface_method_impl{VDIMAGEBACKEND,pfnResize} */
+static DECLCALLBACK(int) vhdResize(void *pBackendData, uint64_t cbSize,
+ PCVDGEOMETRY pPCHSGeometry, PCVDGEOMETRY pLCHSGeometry,
+ unsigned uPercentStart, unsigned uPercentSpan,
+ PVDINTERFACE pVDIfsDisk, PVDINTERFACE pVDIfsImage,
+ PVDINTERFACE pVDIfsOperation)
+{
+ RT_NOREF5(uPercentSpan, uPercentStart, pVDIfsDisk, pVDIfsImage, pVDIfsOperation);
+ PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
+ int rc = VINF_SUCCESS;
+
+ /* Making the image smaller is not supported at the moment. */
+ if (cbSize < pImage->cbSize)
+ rc = VERR_VD_SHRINK_NOT_SUPPORTED;
+ else if (pImage->uImageFlags & VD_IMAGE_FLAGS_FIXED)
+ rc = VERR_NOT_SUPPORTED;
+ else if (cbSize > pImage->cbSize)
+ {
+ unsigned cBlocksAllocated = 0;
+ size_t cbBlock = pImage->cbDataBlock + pImage->cbDataBlockBitmap; /** < Size of a block including the sector bitmap. */
+ uint32_t cBlocksNew = cbSize / pImage->cbDataBlock; /** < New number of blocks in the image after the resize */
+ if (cbSize % pImage->cbDataBlock)
+ cBlocksNew++;
+
+ uint32_t cBlocksOld = pImage->cBlockAllocationTableEntries; /** < Number of blocks before the resize. */
+ uint64_t cbBlockspaceNew = RT_ALIGN_32(cBlocksNew * sizeof(uint32_t), VHD_SECTOR_SIZE); /** < Required space for the block array after the resize. */
+ uint64_t offStartDataNew = RT_ALIGN_32(pImage->uBlockAllocationTableOffset + cbBlockspaceNew, VHD_SECTOR_SIZE); /** < New start offset for block data after the resize */
+ uint64_t offStartDataOld = ~0ULL;
+
+ /* Go through the BAT and find the data start offset. */
+ for (unsigned idxBlock = 0; idxBlock < pImage->cBlockAllocationTableEntries; idxBlock++)
+ {
+ if (pImage->pBlockAllocationTable[idxBlock] != ~0U)
+ {
+ uint64_t offStartBlock = (uint64_t)pImage->pBlockAllocationTable[idxBlock] * VHD_SECTOR_SIZE;
+ if (offStartBlock < offStartDataOld)
+ offStartDataOld = offStartBlock;
+ cBlocksAllocated++;
+ }
+ }
+
+ if ( offStartDataOld != offStartDataNew
+ && cBlocksAllocated > 0)
+ {
+ /* Calculate how many sectors nee to be relocated. */
+ uint64_t cbOverlapping = offStartDataNew - offStartDataOld;
+ unsigned cBlocksReloc = (unsigned)(cbOverlapping / cbBlock);
+ if (cbOverlapping % cbBlock)
+ cBlocksReloc++;
+
+ cBlocksReloc = RT_MIN(cBlocksReloc, cBlocksAllocated);
+ offStartDataNew = offStartDataOld;
+
+ /* Do the relocation. */
+ LogFlow(("Relocating %u blocks\n", cBlocksReloc));
+
+ /*
+ * Get the blocks we need to relocate first, they are appended to the end
+ * of the image.
+ */
+ void *pvBuf = NULL, *pvZero = NULL;
+ do
+ {
+ /* Allocate data buffer. */
+ pvBuf = RTMemAllocZ(cbBlock);
+ if (!pvBuf)
+ {
+ rc = VERR_NO_MEMORY;
+ break;
+ }
+
+ /* Allocate buffer for overwriting with zeroes. */
+ pvZero = RTMemAllocZ(cbBlock);
+ if (!pvZero)
+ {
+ rc = VERR_NO_MEMORY;
+ break;
+ }
+
+ for (unsigned i = 0; i < cBlocksReloc; i++)
+ {
+ uint32_t uBlock = offStartDataNew / VHD_SECTOR_SIZE;
+
+ /* Search the index in the block table. */
+ for (unsigned idxBlock = 0; idxBlock < cBlocksOld; idxBlock++)
+ {
+ if (pImage->pBlockAllocationTable[idxBlock] == uBlock)
+ {
+ /* Read data and append to the end of the image. */
+ rc = vdIfIoIntFileReadSync(pImage->pIfIo, pImage->pStorage,
+ offStartDataNew, pvBuf, cbBlock);
+ if (RT_FAILURE(rc))
+ break;
+
+ rc = vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage,
+ pImage->uCurrentEndOfFile, pvBuf, cbBlock);
+ if (RT_FAILURE(rc))
+ break;
+
+ /* Zero out the old block area. */
+ rc = vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage,
+ offStartDataNew, pvZero, cbBlock);
+ if (RT_FAILURE(rc))
+ break;
+
+ /* Update block counter. */
+ pImage->pBlockAllocationTable[idxBlock] = pImage->uCurrentEndOfFile / VHD_SECTOR_SIZE;
+
+ pImage->uCurrentEndOfFile += cbBlock;
+
+ /* Continue with the next block. */
+ break;
+ }
+ }
+
+ if (RT_FAILURE(rc))
+ break;
+
+ offStartDataNew += cbBlock;
+ }
+ } while (0);
+
+ if (pvBuf)
+ RTMemFree(pvBuf);
+ if (pvZero)
+ RTMemFree(pvZero);
+ }
+
+ /*
+ * Relocation done, expand the block array and update the header with
+ * the new data.
+ */
+ if (RT_SUCCESS(rc))
+ {
+ uint32_t *paBlocksNew = (uint32_t *)RTMemRealloc(pImage->pBlockAllocationTable, cBlocksNew * sizeof(uint32_t));
+ if (paBlocksNew)
+ {
+ pImage->pBlockAllocationTable = paBlocksNew;
+
+ /* Mark the new blocks as unallocated. */
+ for (unsigned idxBlock = cBlocksOld; idxBlock < cBlocksNew; idxBlock++)
+ pImage->pBlockAllocationTable[idxBlock] = ~0U;
+ }
+ else
+ rc = VERR_NO_MEMORY;
+
+ if (RT_SUCCESS(rc))
+ {
+ /* Write the block array before updating the rest. */
+ rc = vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage,
+ pImage->uBlockAllocationTableOffset,
+ pImage->pBlockAllocationTable,
+ cBlocksNew * sizeof(uint32_t));
+ }
+
+ if (RT_SUCCESS(rc))
+ {
+ /* Update size and new block count. */
+ pImage->cBlockAllocationTableEntries = cBlocksNew;
+ pImage->cbSize = cbSize;
+
+ /* Update geometry. */
+ pImage->PCHSGeometry = *pPCHSGeometry;
+ pImage->LCHSGeometry = *pLCHSGeometry;
+ }
+ }
+
+ /* Update header information in base image file. */
+ pImage->fDynHdrNeedsUpdate = true;
+ vhdFlushImage(pImage);
+ }
+ /* Same size doesn't change the image at all. */
+
+ LogFlowFunc(("returns %Rrc\n", rc));
+ return rc;
+}
+
+/** @interface_method_impl{VDIMAGEBACKEND,pfnRepair} */
+static DECLCALLBACK(int) vhdRepair(const char *pszFilename, PVDINTERFACE pVDIfsDisk,
+ PVDINTERFACE pVDIfsImage, uint32_t fFlags)
+{
+ LogFlowFunc(("pszFilename=\"%s\" pVDIfsDisk=%#p pVDIfsImage=%#p\n", pszFilename, pVDIfsDisk, pVDIfsImage));
+ int rc;
+ PVDINTERFACEERROR pIfError;
+ PVDINTERFACEIOINT pIfIo;
+ PVDIOSTORAGE pStorage = NULL;
+ uint64_t cbFile;
+ VHDFooter vhdFooter;
+ VHDDynamicDiskHeader dynamicDiskHeader;
+ uint32_t *paBat = NULL;
+ uint32_t *pu32BlockBitmap = NULL;
+
+ pIfIo = VDIfIoIntGet(pVDIfsImage);
+ AssertPtrReturn(pIfIo, VERR_INVALID_PARAMETER);
+
+ pIfError = VDIfErrorGet(pVDIfsDisk);
+
+ do
+ {
+ uint64_t offDynamicDiskHeader = 0;
+ uint64_t offBat = 0;
+ uint64_t offFooter = 0;
+ uint32_t cBatEntries = 0;
+ bool fDynamic = false;
+ bool fRepairFooter = false;
+ bool fRepairBat = false;
+ bool fRepairDynHeader = false;
+
+ rc = vdIfIoIntFileOpen(pIfIo, pszFilename,
+ VDOpenFlagsToFileOpenFlags( fFlags & VD_REPAIR_DRY_RUN
+ ? VD_OPEN_FLAGS_READONLY
+ : 0,
+ false /* fCreate */),
+ &pStorage);
+ if (RT_FAILURE(rc))
+ {
+ rc = vdIfError(pIfError, rc, RT_SRC_POS, "Failed to open image \"%s\"", pszFilename);
+ break;
+ }
+
+ rc = vdIfIoIntFileGetSize(pIfIo, pStorage, &cbFile);
+ if (RT_FAILURE(rc))
+ {
+ rc = vdIfError(pIfError, rc, RT_SRC_POS, "Failed to query image size");
+ break;
+ }
+
+ if (cbFile < sizeof(VHDFooter))
+ {
+ rc = vdIfError(pIfError, VERR_VD_INVALID_SIZE, RT_SRC_POS,
+ "Image must be at least %u bytes (got %llu)",
+ sizeof(VHDFooter), cbFile);
+ break;
+ }
+
+ rc = vdIfIoIntFileReadSync(pIfIo, pStorage, cbFile - sizeof(VHDFooter),
+ &vhdFooter, sizeof(VHDFooter));
+ if (RT_FAILURE(rc))
+ {
+ rc = vdIfError(pIfError, rc, RT_SRC_POS, "Failed to read footer of image");
+ break;
+ }
+
+ if (memcmp(vhdFooter.Cookie, VHD_FOOTER_COOKIE, VHD_FOOTER_COOKIE_SIZE) != 0)
+ {
+ /* Dynamic images have a backup at the beginning of the image. */
+ rc = vdIfIoIntFileReadSync(pIfIo, pStorage, 0,
+ &vhdFooter, sizeof(VHDFooter));
+ if (RT_FAILURE(rc))
+ {
+ rc = vdIfError(pIfError, rc, RT_SRC_POS, "Failed to read header of image");
+ break;
+ }
+
+ /*
+ * Check for the header, if this fails the image is either completely corrupted
+ * and impossible to repair or in another format.
+ */
+ if (memcmp(vhdFooter.Cookie, VHD_FOOTER_COOKIE, VHD_FOOTER_COOKIE_SIZE) != 0)
+ {
+ rc = vdIfError(pIfError, VERR_VD_IMAGE_REPAIR_IMPOSSIBLE, RT_SRC_POS,
+ "No valid VHD structures found");
+ break;
+ }
+ else
+ vdIfErrorMessage(pIfError, "Missing footer structure, using backup\n");
+
+ /* Remember to fix the footer structure. */
+ fRepairFooter = true;
+ }
+
+ offFooter = cbFile - sizeof(VHDFooter);
+
+ /* Verify that checksums match. */
+ uint32_t u32ChkSumOld = RT_BE2H_U32(vhdFooter.Checksum);
+ vhdFooter.Checksum = 0;
+ uint32_t u32ChkSum = vhdChecksum(&vhdFooter, sizeof(VHDFooter));
+
+ vhdFooter.Checksum = RT_H2BE_U32(u32ChkSum);
+
+ if (u32ChkSumOld != u32ChkSum)
+ {
+ vdIfErrorMessage(pIfError, "Checksum is invalid (should be %u got %u), repairing\n",
+ u32ChkSum, u32ChkSumOld);
+ fRepairFooter = true;
+ break;
+ }
+
+ switch (RT_BE2H_U32(vhdFooter.DiskType))
+ {
+ case VHD_FOOTER_DISK_TYPE_FIXED:
+ fDynamic = false;
+ break;
+ case VHD_FOOTER_DISK_TYPE_DYNAMIC:
+ fDynamic = true;
+ break;
+ case VHD_FOOTER_DISK_TYPE_DIFFERENCING:
+ fDynamic = true;
+ break;
+ default:
+ {
+ rc = vdIfError(pIfError, VERR_VD_IMAGE_REPAIR_IMPOSSIBLE, RT_SRC_POS,
+ "VHD image type %u is not supported",
+ RT_BE2H_U32(vhdFooter.DiskType));
+ break;
+ }
+ }
+
+ /* Load and check dynamic disk header if required. */
+ if (fDynamic)
+ {
+ size_t cbBlock;
+
+ offDynamicDiskHeader = RT_BE2H_U64(vhdFooter.DataOffset);
+ if (offDynamicDiskHeader + sizeof(VHDDynamicDiskHeader) > cbFile)
+ {
+ rc = vdIfError(pIfError, VERR_VD_IMAGE_REPAIR_IMPOSSIBLE, RT_SRC_POS,
+ "VHD image type is not supported");
+ break;
+ }
+
+ rc = vdIfIoIntFileReadSync(pIfIo, pStorage, offDynamicDiskHeader,
+ &dynamicDiskHeader, sizeof(VHDDynamicDiskHeader));
+ if (RT_FAILURE(rc))
+ {
+ rc = vdIfError(pIfError, VERR_VD_IMAGE_REPAIR_IMPOSSIBLE, RT_SRC_POS,
+ "Failed to read dynamic disk header (at %llu), %Rrc",
+ offDynamicDiskHeader, rc);
+ break;
+ }
+
+ /* Verify that checksums match. */
+ u32ChkSumOld = RT_BE2H_U32(dynamicDiskHeader.Checksum);
+ dynamicDiskHeader.Checksum = 0;
+ u32ChkSum = vhdChecksum(&dynamicDiskHeader, sizeof(VHDDynamicDiskHeader));
+
+ dynamicDiskHeader.Checksum = RT_H2BE_U32(u32ChkSum);
+
+ if (u32ChkSumOld != u32ChkSum)
+ {
+ vdIfErrorMessage(pIfError, "Checksum of dynamic disk header is invalid (should be %u got %u), repairing\n",
+ u32ChkSum, u32ChkSumOld);
+ fRepairDynHeader = true;
+ break;
+ }
+
+ /* Read the block allocation table and fix any inconsistencies. */
+ offBat = RT_BE2H_U64(dynamicDiskHeader.TableOffset);
+ cBatEntries = RT_BE2H_U32(dynamicDiskHeader.MaxTableEntries);
+ cbBlock = RT_BE2H_U32(dynamicDiskHeader.BlockSize);
+ cbBlock += cbBlock / VHD_SECTOR_SIZE / 8;
+
+ if (offBat + cBatEntries * sizeof(uint32_t) > cbFile)
+ {
+ rc = vdIfError(pIfError, VERR_VD_IMAGE_REPAIR_IMPOSSIBLE, RT_SRC_POS,
+ "Block allocation table is not inside the image");
+ break;
+ }
+
+ paBat = (uint32_t *)RTMemAllocZ(cBatEntries * sizeof(uint32_t));
+ if (!paBat)
+ {
+ rc = vdIfError(pIfError, VERR_VD_IMAGE_REPAIR_IMPOSSIBLE, RT_SRC_POS,
+ "Could not allocate memory for the block allocation table (%u bytes)",
+ cBatEntries * sizeof(uint32_t));
+ break;
+ }
+
+ rc = vdIfIoIntFileReadSync(pIfIo, pStorage, offBat, paBat,
+ cBatEntries * sizeof(uint32_t));
+ if (RT_FAILURE(rc))
+ {
+ rc = vdIfError(pIfError, VERR_VD_IMAGE_REPAIR_IMPOSSIBLE, RT_SRC_POS,
+ "Could not read block allocation table (at %llu), %Rrc",
+ offBat, rc);
+ break;
+ }
+
+ pu32BlockBitmap = (uint32_t *)RTMemAllocZ(RT_ALIGN_Z(cBatEntries / 8, 4));
+ if (!pu32BlockBitmap)
+ {
+ rc = vdIfError(pIfError, VERR_NO_MEMORY, RT_SRC_POS,
+ "Failed to allocate memory for block bitmap");
+ break;
+ }
+
+ uint32_t idxMinBlock = UINT32_C(0xffffffff);
+ for (uint32_t i = 0; i < cBatEntries; i++)
+ {
+ paBat[i] = RT_BE2H_U32(paBat[i]);
+ if (paBat[i] < idxMinBlock)
+ idxMinBlock = paBat[i];
+ }
+
+ vdIfErrorMessage(pIfError, "First data block at sector %u\n", idxMinBlock);
+
+ for (uint32_t i = 0; i < cBatEntries; i++)
+ {
+ if (paBat[i] != UINT32_C(0xffffffff))
+ {
+ uint64_t offBlock =(uint64_t)paBat[i] * VHD_SECTOR_SIZE;
+
+ /*
+ * Check that the offsets are valid (inside of the image) and
+ * that there are no double references.
+ */
+ if (offBlock + cbBlock > cbFile)
+ {
+ vdIfErrorMessage(pIfError, "Entry %u points to invalid offset %llu, clearing\n",
+ i, offBlock);
+ paBat[i] = UINT32_C(0xffffffff);
+ fRepairBat = true;
+ }
+ else if (offBlock + cbBlock > offFooter)
+ {
+ vdIfErrorMessage(pIfError, "Entry %u intersects with footer, aligning footer\n",
+ i);
+ offFooter = offBlock + cbBlock;
+ fRepairBat = true;
+ }
+
+ if ( paBat[i] != UINT32_C(0xffffffff)
+ && ASMBitTestAndSet(pu32BlockBitmap, (uint32_t)((paBat[i] - idxMinBlock) / (cbBlock / VHD_SECTOR_SIZE))))
+ {
+ vdIfErrorMessage(pIfError, "Entry %u points to an already referenced data block, clearing\n",
+ i);
+ paBat[i] = UINT32_C(0xffffffff);
+ fRepairBat = true;
+ }
+ }
+ }
+ }
+
+ /* Write repaired structures now. */
+ if (!(fRepairBat || fRepairDynHeader || fRepairFooter))
+ vdIfErrorMessage(pIfError, "VHD image is in a consistent state, no repair required\n");
+ else if (!(fFlags & VD_REPAIR_DRY_RUN))
+ {
+ if (fRepairBat)
+ {
+ for (uint32_t i = 0; i < cBatEntries; i++)
+ paBat[i] = RT_H2BE_U32(paBat[i]);
+
+ vdIfErrorMessage(pIfError, "Writing repaired block allocation table...\n");
+
+ rc = vdIfIoIntFileWriteSync(pIfIo, pStorage, offBat, paBat,
+ cBatEntries * sizeof(uint32_t));
+ if (RT_FAILURE(rc))
+ {
+ rc = vdIfError(pIfError, VERR_VD_IMAGE_REPAIR_IMPOSSIBLE, RT_SRC_POS,
+ "Could not write repaired block allocation table (at %llu), %Rrc",
+ offBat, rc);
+ break;
+ }
+ }
+
+ if (fRepairDynHeader)
+ {
+ Assert(fDynamic);
+
+ vdIfErrorMessage(pIfError, "Writing repaired dynamic disk header...\n");
+ rc = vdIfIoIntFileWriteSync(pIfIo, pStorage, offDynamicDiskHeader, &dynamicDiskHeader,
+ sizeof(VHDDynamicDiskHeader));
+ if (RT_FAILURE(rc))
+ {
+ rc = vdIfError(pIfError, VERR_VD_IMAGE_REPAIR_IMPOSSIBLE, RT_SRC_POS,
+ "Could not write repaired dynamic disk header (at %llu), %Rrc",
+ offDynamicDiskHeader, rc);
+ break;
+ }
+ }
+
+ if (fRepairFooter)
+ {
+ vdIfErrorMessage(pIfError, "Writing repaired Footer...\n");
+
+ if (fDynamic)
+ {
+ /* Write backup at image beginning. */
+ rc = vdIfIoIntFileWriteSync(pIfIo, pStorage, 0, &vhdFooter,
+ sizeof(VHDFooter));
+ if (RT_FAILURE(rc))
+ {
+ rc = vdIfError(pIfError, VERR_VD_IMAGE_REPAIR_IMPOSSIBLE, RT_SRC_POS,
+ "Could not write repaired backup footer (at %llu), %Rrc",
+ 0, rc);
+ break;
+ }
+ }
+
+ rc = vdIfIoIntFileWriteSync(pIfIo, pStorage, offFooter, &vhdFooter,
+ sizeof(VHDFooter));
+ if (RT_FAILURE(rc))
+ {
+ rc = vdIfError(pIfError, VERR_VD_IMAGE_REPAIR_IMPOSSIBLE, RT_SRC_POS,
+ "Could not write repaired footer (at %llu), %Rrc",
+ cbFile - sizeof(VHDFooter), rc);
+ break;
+ }
+ }
+
+ vdIfErrorMessage(pIfError, "Corrupted VHD image repaired successfully\n");
+ }
+ } while(0);
+
+ if (paBat)
+ RTMemFree(paBat);
+
+ if (pu32BlockBitmap)
+ RTMemFree(pu32BlockBitmap);
+
+ if (pStorage)
+ {
+ int rc2 = vdIfIoIntFileClose(pIfIo, pStorage);
+ if (RT_SUCCESS(rc))
+ rc = rc2; /* Propagate status code only when repairing the image was successful. */
+ }
+
+ LogFlowFunc(("returns %Rrc\n", rc));
+ return rc;
+}
+
+
+const VDIMAGEBACKEND g_VhdBackend =
+{
+ /* u32Version */
+ VD_IMGBACKEND_VERSION,
+ /* pszBackendName */
+ "VHD",
+ /* uBackendCaps */
+ VD_CAP_UUID | VD_CAP_DIFF | VD_CAP_FILE |
+ VD_CAP_CREATE_FIXED | VD_CAP_CREATE_DYNAMIC |
+ VD_CAP_ASYNC | VD_CAP_VFS | VD_CAP_PREFERRED,
+ /* paFileExtensions */
+ s_aVhdFileExtensions,
+ /* paConfigInfo */
+ NULL,
+ /* pfnProbe */
+ vhdProbe,
+ /* pfnOpen */
+ vhdOpen,
+ /* pfnCreate */
+ vhdCreate,
+ /* pfnRename */
+ vhdRename,
+ /* pfnClose */
+ vhdClose,
+ /* pfnRead */
+ vhdRead,
+ /* pfnWrite */
+ vhdWrite,
+ /* pfnFlush */
+ vhdFlush,
+ /* pfnDiscard */
+ NULL,
+ /* pfnGetVersion */
+ vhdGetVersion,
+ /* pfnGetFileSize */
+ vhdGetFileSize,
+ /* pfnGetPCHSGeometry */
+ vhdGetPCHSGeometry,
+ /* pfnSetPCHSGeometry */
+ vhdSetPCHSGeometry,
+ /* pfnGetLCHSGeometry */
+ vhdGetLCHSGeometry,
+ /* pfnSetLCHSGeometry */
+ vhdSetLCHSGeometry,
+ /* pfnQueryRegions */
+ vhdQueryRegions,
+ /* pfnRegionListRelease */
+ vhdRegionListRelease,
+ /* pfnGetImageFlags */
+ vhdGetImageFlags,
+ /* pfnGetOpenFlags */
+ vhdGetOpenFlags,
+ /* pfnSetOpenFlags */
+ vhdSetOpenFlags,
+ /* pfnGetComment */
+ vhdGetComment,
+ /* pfnSetComment */
+ vhdSetComment,
+ /* pfnGetUuid */
+ vhdGetUuid,
+ /* pfnSetUuid */
+ vhdSetUuid,
+ /* pfnGetModificationUuid */
+ vhdGetModificationUuid,
+ /* pfnSetModificationUuid */
+ vhdSetModificationUuid,
+ /* pfnGetParentUuid */
+ vhdGetParentUuid,
+ /* pfnSetParentUuid */
+ vhdSetParentUuid,
+ /* pfnGetParentModificationUuid */
+ vhdGetParentModificationUuid,
+ /* pfnSetParentModificationUuid */
+ vhdSetParentModificationUuid,
+ /* pfnDump */
+ vhdDump,
+ /* pfnGetTimestamp */
+ vhdGetTimestamp,
+ /* pfnGetParentTimestamp */
+ vhdGetParentTimestamp,
+ /* pfnSetParentTimestamp */
+ vhdSetParentTimestamp,
+ /* pfnGetParentFilename */
+ vhdGetParentFilename,
+ /* pfnSetParentFilename */
+ vhdSetParentFilename,
+ /* pfnComposeLocation */
+ genericFileComposeLocation,
+ /* pfnComposeName */
+ genericFileComposeName,
+ /* pfnCompact */
+ vhdCompact,
+ /* pfnResize */
+ vhdResize,
+ /* pfnRepair */
+ vhdRepair,
+ /* pfnTraverseMetadata */
+ NULL,
+ /* u32VersionEnd */
+ VD_IMGBACKEND_VERSION
+};