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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:17:27 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:17:27 +0000
commitf215e02bf85f68d3a6106c2a1f4f7f063f819064 (patch)
tree6bb5b92c046312c4e95ac2620b10ddf482d3fa8b /include/VBox/vd-image-backend.h
parentInitial commit. (diff)
downloadvirtualbox-f215e02bf85f68d3a6106c2a1f4f7f063f819064.tar.xz
virtualbox-f215e02bf85f68d3a6106c2a1f4f7f063f819064.zip
Adding upstream version 7.0.14-dfsg.upstream/7.0.14-dfsg
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'include/VBox/vd-image-backend.h')
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diff --git a/include/VBox/vd-image-backend.h b/include/VBox/vd-image-backend.h
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+/** @file
+ * VD: Image backend interface.
+ */
+
+/*
+ * Copyright (C) 2006-2023 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>.
+ *
+ * The contents of this file may alternatively be used under the terms
+ * of the Common Development and Distribution License Version 1.0
+ * (CDDL), a copy of it is provided in the "COPYING.CDDL" file included
+ * in the VirtualBox distribution, in which case the provisions of the
+ * CDDL are applicable instead of those of the GPL.
+ *
+ * You may elect to license modified versions of this file under the
+ * terms and conditions of either the GPL or the CDDL or both.
+ *
+ * SPDX-License-Identifier: GPL-3.0-only OR CDDL-1.0
+ */
+
+#ifndef VBOX_INCLUDED_vd_image_backend_h
+#define VBOX_INCLUDED_vd_image_backend_h
+#ifndef RT_WITHOUT_PRAGMA_ONCE
+# pragma once
+#endif
+
+#include <VBox/vd.h>
+#include <VBox/vd-common.h>
+#include <VBox/vd-ifs-internal.h>
+
+
+/** @name VBox HDD backend write flags
+ * @{
+ */
+/** Do not allocate a new block on this write. This is just an advisory
+ * flag. The backend may still decide in some circumstances that it wants
+ * to ignore this flag (which may cause extra dynamic image expansion). */
+#define VD_WRITE_NO_ALLOC RT_BIT(1)
+/** @}*/
+
+/** @name VBox HDD backend discard flags
+ * @{
+ */
+/** Don't discard block but mark the given range as unused
+ * (usually by writing 0's to it).
+ * This doesn't require the range to be aligned on a block boundary but
+ * the image size might not be decreased. */
+#define VD_DISCARD_MARK_UNUSED RT_BIT(0)
+/** @}*/
+
+/** @name VBox HDD backend metadata traverse flags
+ * @{
+ */
+/** Include per block metadata while traversing the metadata.
+ * This might take much longer instead of traversing just global metadata. */
+#define VD_TRAVERSE_METADATA_INCLUDE_PER_BLOCK_METADATA RT_BIT(0)
+/** @}*/
+
+/**
+ * Image format backend interface used by VBox HDD Container implementation.
+ */
+typedef struct VDIMAGEBACKEND
+{
+ /** Structure version. VD_IMGBACKEND_VERSION defines the current version. */
+ uint32_t u32Version;
+ /** The name of the backend (constant string). */
+ const char *pszBackendName;
+ /** The capabilities of the backend. */
+ uint64_t uBackendCaps;
+
+ /**
+ * Pointer to a NULL-terminated array, containing the supported
+ * file extensions. Note that some backends do not work on files, so this
+ * pointer may just contain NULL.
+ */
+ PCVDFILEEXTENSION paFileExtensions;
+
+ /**
+ * Pointer to an array of structs describing each supported config key.
+ * Terminated by a NULL config key. Note that some backends do not support
+ * the configuration interface, so this pointer may just contain NULL.
+ * Mandatory if the backend sets VD_CAP_CONFIG.
+ */
+ PCVDCONFIGINFO paConfigInfo;
+
+ /**
+ * Check whether the file is supported by the backend.
+ *
+ * @returns VBox status code.
+ * @param pszFilename Name of the image file.
+ * @param pVDIfsDisk Pointer to the per-disk VD interface list.
+ * @param pVDIfsImage Pointer to the per-image VD interface list.
+ * @param enmDesiredType The desired image type, VDTYPE_INVALID if anything goes.
+ * @param penmType Returns the supported device type on success.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnProbe, (const char *pszFilename, PVDINTERFACE pVDIfsDisk,
+ PVDINTERFACE pVDIfsImage, VDTYPE enmDesiredType, VDTYPE *penmType));
+
+ /**
+ * Open a disk image.
+ *
+ * @returns VBox status code.
+ * @param pszFilename Name of the image file to open. Guaranteed to be available and
+ * unchanged during the lifetime of this image.
+ * @param uOpenFlags Image file open mode, see VD_OPEN_FLAGS_* constants.
+ * @param pVDIfsDisk Pointer to the per-disk VD interface list.
+ * @param pVDIfsImage Pointer to the per-image VD interface list.
+ * @param enmType Requested type of the image.
+ * @param ppBackendData Opaque state data for this image.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnOpen, (const char *pszFilename, unsigned uOpenFlags,
+ PVDINTERFACE pVDIfsDisk, PVDINTERFACE pVDIfsImage,
+ VDTYPE enmType, void **ppBackendData));
+
+ /**
+ * Create a disk image.
+ *
+ * @returns VBox status code.
+ * @param pszFilename Name of the image file to create. Guaranteed to be available and
+ * unchanged during the lifetime of this image.
+ * @param cbSize Image size in bytes.
+ * @param uImageFlags Flags specifying special image features.
+ * @param pszComment Pointer to image comment. NULL is ok.
+ * @param pPCHSGeometry Physical drive geometry CHS <= (16383,16,255).
+ * @param pLCHSGeometry Logical drive geometry CHS <= (1024,255,63).
+ * @param pUuid New UUID of the image. Not NULL.
+ * @param uOpenFlags Image file open mode, see VD_OPEN_FLAGS_* constants.
+ * @param uPercentStart Starting value for progress percentage.
+ * @param uPercentSpan Span for varying progress percentage.
+ * @param pVDIfsDisk Pointer to the per-disk VD interface list.
+ * @param pVDIfsImage Pointer to the per-image VD interface list.
+ * @param pVDIfsOperation Pointer to the per-operation VD interface list.
+ * @param enmType Requested type of the image.
+ * @param ppBackendData Opaque state data for this image.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnCreate, (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));
+
+ /**
+ * Rename a disk image. Only needs to work as long as the operating
+ * system's rename file functionality is usable. If an attempt is made to
+ * rename an image to a location on another disk/filesystem, this function
+ * may just fail with an appropriate error code (not changing the opened
+ * image data at all). Also works only on images which actually refer to
+ * regular files. May be NULL.
+ *
+ * @returns VBox status code.
+ * @param pBackendData Opaque state data for this image.
+ * @param pszFilename New name of the image file. Guaranteed to be available and
+ * unchanged during the lifetime of this image.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnRename, (void *pBackendData, const char *pszFilename));
+
+ /**
+ * Close a disk image.
+ *
+ * @returns VBox status code.
+ * @param pBackendData Opaque state data for this image.
+ * @param fDelete If true, delete the image from the host disk.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnClose, (void *pBackendData, bool fDelete));
+
+ /**
+ * Start a read request.
+ *
+ * @returns VBox status code.
+ * @param pBackendData Opaque state data for this image.
+ * @param uOffset The offset of the virtual disk to read from.
+ * @param cbToRead How many bytes to read.
+ * @param pIoCtx I/O context associated with this request.
+ * @param pcbActuallyRead Pointer to returned number of bytes read.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnRead, (void *pBackendData, uint64_t uOffset, size_t cbToRead,
+ PVDIOCTX pIoCtx, size_t *pcbActuallyRead));
+
+ /**
+ * Start a write request.
+ *
+ * @returns VBox status code.
+ * @param pBackendData Opaque state data for this image.
+ * @param uOffset The offset of the virtual disk to write to.
+ * @param cbToWrite How many bytes to write.
+ * @param pIoCtx I/O context associated with this request.
+ * @param pcbWriteProcess Pointer to returned number of bytes that could
+ * be processed. In case the function returned
+ * VERR_VD_BLOCK_FREE this is the number of bytes
+ * that could be written in a full block write,
+ * when prefixed/postfixed by the appropriate
+ * amount of (previously read) padding data.
+ * @param pcbPreRead Pointer to the returned amount of data that must
+ * be prefixed to perform a full block write.
+ * @param pcbPostRead Pointer to the returned amount of data that must
+ * be postfixed to perform a full block write.
+ * @param fWrite Flags which affect write behavior. Combination
+ * of the VD_WRITE_* flags.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnWrite, (void *pBackendData, uint64_t uOffset, size_t cbToWrite,
+ PVDIOCTX pIoCtx,
+ size_t *pcbWriteProcess, size_t *pcbPreRead,
+ size_t *pcbPostRead, unsigned fWrite));
+
+ /**
+ * Flush data to disk.
+ *
+ * @returns VBox status code.
+ * @param pBackendData Opaque state data for this image.
+ * @param pIoCtx I/O context associated with this request.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnFlush, (void *pBackendData, PVDIOCTX pIoCtx));
+
+ /**
+ * Discards the given amount of bytes decreasing the size of the image if possible
+ *
+ * @returns VBox status code.
+ * @retval VERR_VD_DISCARD_ALIGNMENT_NOT_MET if the range doesn't meet the required alignment
+ * for the discard.
+ * @param pBackendData Opaque state data for this image.
+ * @param pIoCtx I/O context associated with this request.
+ * @param uOffset The offset of the first byte to discard.
+ * @param cbDiscard How many bytes to discard.
+ * @param pcbPreAllocated Pointer to the returned amount of bytes that must
+ * be discarded before the range to perform a full
+ * block discard.
+ * @param pcbPostAllocated Pointer to the returned amount of bytes that must
+ * be discarded after the range to perform a full
+ * block discard.
+ * @param pcbActuallyDiscarded Pointer to the returned amount of bytes which
+ * could be actually discarded.
+ * @param ppbmAllocationBitmap Where to store the pointer to the allocation bitmap
+ * if VERR_VD_DISCARD_ALIGNMENT_NOT_MET is returned or NULL
+ * if the allocation bitmap should be returned.
+ * @param fDiscard Flags which affect discard behavior. Combination
+ * of the VD_DISCARD_* flags.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnDiscard, (void *pBackendData, PVDIOCTX pIoCtx,
+ uint64_t uOffset, size_t cbDiscard,
+ size_t *pcbPreAllocated,
+ size_t *pcbPostAllocated,
+ size_t *pcbActuallyDiscarded,
+ void **ppbmAllocationBitmap,
+ unsigned fDiscard));
+
+ /**
+ * Get the version of a disk image.
+ *
+ * @returns version of disk image.
+ * @param pBackendData Opaque state data for this image.
+ */
+ DECLR3CALLBACKMEMBER(unsigned, pfnGetVersion, (void *pBackendData));
+
+ /**
+ * Get the file size of a disk image.
+ *
+ * @returns size of disk image in bytes.
+ * @param pBackendData Opaque state data for this image.
+ */
+ DECLR3CALLBACKMEMBER(uint64_t, pfnGetFileSize, (void *pBackendData));
+
+ /**
+ * Get virtual disk PCHS geometry stored in a disk image.
+ *
+ * @returns VBox status code.
+ * @returns VERR_VD_GEOMETRY_NOT_SET if no geometry present in the image.
+ * @param pBackendData Opaque state data for this image.
+ * @param pPCHSGeometry Where to store the geometry. Not NULL.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnGetPCHSGeometry, (void *pBackendData, PVDGEOMETRY pPCHSGeometry));
+
+ /**
+ * Set virtual disk PCHS geometry stored in a disk image.
+ * Only called if geometry is different than before.
+ *
+ * @returns VBox status code.
+ * @param pBackendData Opaque state data for this image.
+ * @param pPCHSGeometry Where to load the geometry from. Not NULL.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnSetPCHSGeometry, (void *pBackendData, PCVDGEOMETRY pPCHSGeometry));
+
+ /**
+ * Get virtual disk LCHS geometry stored in a disk image.
+ *
+ * @returns VBox status code.
+ * @returns VERR_VD_GEOMETRY_NOT_SET if no geometry present in the image.
+ * @param pBackendData Opaque state data for this image.
+ * @param pLCHSGeometry Where to store the geometry. Not NULL.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnGetLCHSGeometry, (void *pBackendData, PVDGEOMETRY pLCHSGeometry));
+
+ /**
+ * Set virtual disk LCHS geometry stored in a disk image.
+ * Only called if geometry is different than before.
+ *
+ * @returns VBox status code.
+ * @param pBackendData Opaque state data for this image.
+ * @param pLCHSGeometry Where to load the geometry from. Not NULL.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnSetLCHSGeometry, (void *pBackendData, PCVDGEOMETRY pLCHSGeometry));
+
+ /**
+ * Returns a region list for the disk image if supported, optional.
+ *
+ * @returns VBox status code.
+ * @retval VERR_NOT_SUPPORTED if region lists are not supported for this kind of image.
+ * @param pBackendData Opaque state data for this image.
+ * @param ppRegionList Where to store the pointer to the region list on success.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnQueryRegions, (void *pBackendData, PCVDREGIONLIST *ppRegionList));
+
+ /**
+ * Releases the region list acquired with VDIMAGEBACKEND::pfnQueryRegions() before.
+ *
+ * @param pBackendData Opaque state data for this image.
+ * @param pRegionList The region list to release.
+ */
+ DECLR3CALLBACKMEMBER(void, pfnRegionListRelease, (void *pBackendData, PCVDREGIONLIST pRegionList));
+
+ /**
+ * Get the image flags of a disk image.
+ *
+ * @returns image flags of disk image (VD_IMAGE_FLAGS_XXX).
+ * @param pBackendData Opaque state data for this image.
+ */
+ DECLR3CALLBACKMEMBER(unsigned, pfnGetImageFlags, (void *pBackendData));
+
+ /**
+ * Get the open flags of a disk image.
+ *
+ * @returns open flags of disk image (VD_OPEN_FLAGS_XXX).
+ * @param pBackendData Opaque state data for this image.
+ */
+ DECLR3CALLBACKMEMBER(unsigned, pfnGetOpenFlags, (void *pBackendData));
+
+ /**
+ * Set the open flags of a disk image.
+ *
+ * May cause the image to be locked in a different mode or be reopened (which
+ * can fail).
+ *
+ * @returns VBox status code.
+ * @param pBackendData Opaque state data for this image.
+ * @param uOpenFlags New open flags for this image (VD_OPEN_FLAGS_XXX).
+ */
+ DECLR3CALLBACKMEMBER(int, pfnSetOpenFlags, (void *pBackendData, unsigned uOpenFlags));
+
+ /**
+ * Get comment of a disk image.
+ *
+ * @returns VBox status code.
+ * @param pBackendData Opaque state data for this image.
+ * @param pszComment Where to store the comment.
+ * @param cbComment Size of the comment buffer.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnGetComment, (void *pBackendData, char *pszComment, size_t cbComment));
+
+ /**
+ * Set comment of a disk image.
+ *
+ * @returns VBox status code.
+ * @param pBackendData Opaque state data for this image.
+ * @param pszComment Where to get the comment from. NULL resets comment.
+ * The comment is silently truncated if the image format
+ * limit is exceeded.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnSetComment, (void *pBackendData, const char *pszComment));
+
+ /**
+ * Get UUID of a disk image.
+ *
+ * @returns VBox status code.
+ * @param pBackendData Opaque state data for this image.
+ * @param pUuid Where to store the image UUID.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnGetUuid, (void *pBackendData, PRTUUID pUuid));
+
+ /**
+ * Set UUID of a disk image.
+ *
+ * @returns VBox status code.
+ * @param pBackendData Opaque state data for this image.
+ * @param pUuid Where to get the image UUID from.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnSetUuid, (void *pBackendData, PCRTUUID pUuid));
+
+ /**
+ * Get last modification UUID of a disk image.
+ *
+ * @returns VBox status code.
+ * @param pBackendData Opaque state data for this image.
+ * @param pUuid Where to store the image modification UUID.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnGetModificationUuid, (void *pBackendData, PRTUUID pUuid));
+
+ /**
+ * Set last modification UUID of a disk image.
+ *
+ * @returns VBox status code.
+ * @param pBackendData Opaque state data for this image.
+ * @param pUuid Where to get the image modification UUID from.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnSetModificationUuid, (void *pBackendData, PCRTUUID pUuid));
+
+ /**
+ * Get parent UUID of a disk image.
+ *
+ * @returns VBox status code.
+ * @param pBackendData Opaque state data for this image.
+ * @param pUuid Where to store the parent image UUID.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnGetParentUuid, (void *pBackendData, PRTUUID pUuid));
+
+ /**
+ * Set parent UUID of a disk image.
+ *
+ * @returns VBox status code.
+ * @param pBackendData Opaque state data for this image.
+ * @param pUuid Where to get the parent image UUID from.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnSetParentUuid, (void *pBackendData, PCRTUUID pUuid));
+
+ /**
+ * Get parent modification UUID of a disk image.
+ *
+ * @returns VBox status code.
+ * @param pBackendData Opaque state data for this image.
+ * @param pUuid Where to store the parent image modification UUID.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnGetParentModificationUuid, (void *pBackendData, PRTUUID pUuid));
+
+ /**
+ * Set parent modification UUID of a disk image.
+ *
+ * @returns VBox status code.
+ * @param pBackendData Opaque state data for this image.
+ * @param pUuid Where to get the parent image modification UUID from.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnSetParentModificationUuid, (void *pBackendData, PCRTUUID pUuid));
+
+ /**
+ * Dump information about a disk image.
+ *
+ * @param pBackendData Opaque state data for this image.
+ */
+ DECLR3CALLBACKMEMBER(void, pfnDump, (void *pBackendData));
+
+ /**
+ * Get a time stamp of a disk image. May be NULL.
+ *
+ * @returns VBox status code.
+ * @param pBackendData Opaque state data for this image.
+ * @param pTimestamp Where to store the time stamp.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnGetTimestamp, (void *pBackendData, PRTTIMESPEC pTimestamp));
+
+ /**
+ * Get the parent time stamp of a disk image. May be NULL.
+ *
+ * @returns VBox status code.
+ * @param pBackendData Opaque state data for this image.
+ * @param pTimestamp Where to store the time stamp.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnGetParentTimestamp, (void *pBackendData, PRTTIMESPEC pTimestamp));
+
+ /**
+ * Set the parent time stamp of a disk image. May be NULL.
+ *
+ * @returns VBox status code.
+ * @param pBackendData Opaque state data for this image.
+ * @param pTimestamp Where to get the time stamp from.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnSetParentTimestamp, (void *pBackendData, PCRTTIMESPEC pTimestamp));
+
+ /**
+ * Get the relative path to parent image. May be NULL.
+ *
+ * @returns VBox status code.
+ * @param pBackendData Opaque state data for this image.
+ * @param ppszParentFilename Where to store the path.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnGetParentFilename, (void *pBackendData, char **ppszParentFilename));
+
+ /**
+ * Set the relative path to parent image. May be NULL.
+ *
+ * @returns VBox status code.
+ * @param pBackendData Opaque state data for this image.
+ * @param pszParentFilename Where to get the path from.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnSetParentFilename, (void *pBackendData, const char *pszParentFilename));
+
+ /** Returns a human readable hard disk location string given a
+ * set of hard disk configuration keys. The returned string is an
+ * equivalent of the full file path for image-based hard disks.
+ * Mandatory for backends with no VD_CAP_FILE and NULL otherwise. */
+ DECLR3CALLBACKMEMBER(int, pfnComposeLocation, (PVDINTERFACE pConfig, char **pszLocation));
+
+ /** Returns a human readable hard disk name string given a
+ * set of hard disk configuration keys. The returned string is an
+ * equivalent of the file name part in the full file path for
+ * image-based hard disks. Mandatory for backends with no
+ * VD_CAP_FILE and NULL otherwise. */
+ DECLR3CALLBACKMEMBER(int, pfnComposeName, (PVDINTERFACE pConfig, char **pszName));
+
+ /**
+ * Compact the image. The pointer may be NULL, indicating that this
+ * isn't supported yet (for file-based images) or not necessary.
+ *
+ * @returns VBox status code.
+ * @returns VERR_NOT_SUPPORTED if this image cannot be compacted yet.
+ * @param pBackendData Opaque state data for this image.
+ * @param uPercentStart Starting value for progress percentage.
+ * @param uPercentSpan Span for varying progress percentage.
+ * @param pVDIfsDisk Pointer to the per-disk VD interface list.
+ * @param pVDIfsImage Pointer to the per-image VD interface list.
+ * @param pVDIfsOperation Pointer to the per-operation VD interface list.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnCompact, (void *pBackendData,
+ unsigned uPercentStart, unsigned uPercentSpan,
+ PVDINTERFACE pVDIfsDisk,
+ PVDINTERFACE pVDIfsImage,
+ PVDINTERFACE pVDIfsOperation));
+
+ /**
+ * Resize the image. The pointer may be NULL, indicating that this
+ * isn't supported yet (for file-based images) or not necessary.
+ *
+ * @returns VBox status code.
+ * @returns VERR_NOT_SUPPORTED if this image cannot be resized yet.
+ * @param pBackendData Opaque state data for this image.
+ * @param cbSize New size of the image.
+ * @param pPCHSGeometry Pointer to the new physical disk geometry <= (16383,16,63). Not NULL.
+ * @param pLCHSGeometry Pointer to the new logical disk geometry <= (x,255,63). Not NULL.
+ * @param uPercentStart Starting value for progress percentage.
+ * @param uPercentSpan Span for varying progress percentage.
+ * @param pVDIfsDisk Pointer to the per-disk VD interface list.
+ * @param pVDIfsImage Pointer to the per-image VD interface list.
+ * @param pVDIfsOperation Pointer to the per-operation VD interface list.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnResize, (void *pBackendData,
+ uint64_t cbSize,
+ PCVDGEOMETRY pPCHSGeometry,
+ PCVDGEOMETRY pLCHSGeometry,
+ unsigned uPercentStart, unsigned uPercentSpan,
+ PVDINTERFACE pVDIfsDisk,
+ PVDINTERFACE pVDIfsImage,
+ PVDINTERFACE pVDIfsOperation));
+
+ /**
+ * Try to repair the given image.
+ *
+ * @returns VBox status code.
+ * @param pszFilename Name of the image file.
+ * @param pVDIfsDisk Pointer to the per-disk VD interface list.
+ * @param pVDIfsImage Pointer to the per-image VD interface list.
+ * @param fFlags Combination of the VD_REPAIR_* flags.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnRepair, (const char *pszFilename, PVDINTERFACE pVDIfsDisk,
+ PVDINTERFACE pVDIfsImage, uint32_t fFlags));
+
+ /**
+ * Traverse all metadata of the opened image.
+ *
+ * @returns VBox status code.
+ * @param pBackendData Opaque state data for this image.
+ * @param fFlags Traverse flags, combination of VD_TRAVERSE_METDATA_* defines.
+ * @param pVDIfsDisk Pointer to the per-disk VD interface list.
+ * @param pVDIfsImage Pointer to the per-image VD interface list.
+ * @param pVDIfsOperation Pointer to the per-operation VD interface list.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnTraverseMetadata, (void *pBackendData, uint32_t fFlags,
+ PVDINTERFACE pVDIfsDisk,
+ PVDINTERFACE pVDIfsImage,
+ PVDINTERFACE pVDIfsOperation));
+
+ /** Initialization safty marker. */
+ uint32_t u32VersionEnd;
+
+} VDIMAGEBACKEND;
+
+/** Pointer to VD backend. */
+typedef VDIMAGEBACKEND *PVDIMAGEBACKEND;
+/** Constant pointer to VD backend. */
+typedef const VDIMAGEBACKEND *PCVDIMAGEBACKEND;
+
+/** The current version of the VDIMAGEBACKEND structure. */
+#define VD_IMGBACKEND_VERSION VD_VERSION_MAKE(0xff01, 3, 0)
+
+/** @copydoc VDIMAGEBACKEND::pfnComposeLocation */
+DECLCALLBACK(int) genericFileComposeLocation(PVDINTERFACE pConfig, char **pszLocation);
+/** @copydoc VDIMAGEBACKEND::pfnComposeName */
+DECLCALLBACK(int) genericFileComposeName(PVDINTERFACE pConfig, char **pszName);
+
+#endif /* !VBOX_INCLUDED_vd_image_backend_h */