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+/** @file
+ * IPRT Disk Volume Management API (DVM).
+ */
+
+/*
+ * Copyright (C) 2011-2023 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 IPRT_INCLUDED_dvm_h
+#define IPRT_INCLUDED_dvm_h
+#ifndef RT_WITHOUT_PRAGMA_ONCE
+# pragma once
+#endif
+
+#include <iprt/types.h>
+
+RT_C_DECLS_BEGIN
+
+
+/** @defgroup grp_rt_dvm IPRT Disk Volume Management
+ * @ingroup grp_rt
+ * @{
+ */
+
+/**
+ * Volume type.
+ * Comparable to the FS type in MBR partition maps
+ * or the partition type GUIDs in GPT tables.
+ */
+typedef enum RTDVMVOLTYPE
+{
+ /** Invalid. */
+ RTDVMVOLTYPE_INVALID = 0,
+ /** Unknown. */
+ RTDVMVOLTYPE_UNKNOWN,
+ /** Volume hosts a NTFS filesystem. */
+ RTDVMVOLTYPE_NTFS,
+ /** Volume hosts a FAT12 filesystem. */
+ RTDVMVOLTYPE_FAT12,
+ /** Volume hosts a FAT16 filesystem. */
+ RTDVMVOLTYPE_FAT16,
+ /** Volume hosts a FAT32 filesystem. */
+ RTDVMVOLTYPE_FAT32,
+
+ /** EFI system partition (c12a7328-f81f-11d2-ba4b-00a0c93ec93b). */
+ RTDVMVOLTYPE_EFI_SYSTEM,
+
+ /** Volume hosts a Mac OS X HFS or HFS+ filesystem. */
+ RTDVMVOLTYPE_DARWIN_HFS,
+ /** Volume hosts a Mac OS X APFS filesystem. */
+ RTDVMVOLTYPE_DARWIN_APFS,
+
+ /** Volume hosts a Linux swap. */
+ RTDVMVOLTYPE_LINUX_SWAP,
+ /** Volume hosts a Linux filesystem. */
+ RTDVMVOLTYPE_LINUX_NATIVE,
+ /** Volume hosts a Linux LVM. */
+ RTDVMVOLTYPE_LINUX_LVM,
+ /** Volume hosts a Linux SoftRaid. */
+ RTDVMVOLTYPE_LINUX_SOFTRAID,
+
+ /** Volume hosts a FreeBSD disklabel. */
+ RTDVMVOLTYPE_FREEBSD,
+ /** Volume hosts a NetBSD disklabel. */
+ RTDVMVOLTYPE_NETBSD,
+ /** Volume hosts a OpenBSD disklabel. */
+ RTDVMVOLTYPE_OPENBSD,
+ /** Volume hosts a Solaris volume. */
+ RTDVMVOLTYPE_SOLARIS,
+
+ /** Volume hosts a Windows basic data partition . */
+ RTDVMVOLTYPE_WIN_BASIC,
+ /** Volume hosts a Microsoft reserved partition (MSR). */
+ RTDVMVOLTYPE_WIN_MSR,
+ /** Volume hosts a Windows logical disk manager (LDM) metadata partition. */
+ RTDVMVOLTYPE_WIN_LDM_META,
+ /** Volume hosts a Windows logical disk manager (LDM) data partition. */
+ RTDVMVOLTYPE_WIN_LDM_DATA,
+ /** Volume hosts a Windows recovery partition. */
+ RTDVMVOLTYPE_WIN_RECOVERY,
+ /** Volume hosts a storage spaces partition. */
+ RTDVMVOLTYPE_WIN_STORAGE_SPACES,
+
+ /** Volume hosts an IBM general parallel file system (GPFS). */
+ RTDVMVOLTYPE_IBM_GPFS,
+
+ /** OS/2 (Arca Noae) type 1 partition. */
+ RTDVMVOLTYPE_ARCA_OS2,
+
+ /** End of the valid values. */
+ RTDVMVOLTYPE_END,
+ /** Usual 32bit hack. */
+ RTDVMVOLTYPE_32BIT_HACK = 0x7fffffff
+} RTDVMVOLTYPE;
+
+/** @defgroup grp_dvm_flags Flags used by RTDvmCreate.
+ * @{ */
+/** DVM flags - Blocks are always marked as unused if the volume has
+ * no block status callback set.
+ * The default is to mark them as used. */
+#define DVM_FLAGS_NO_STATUS_CALLBACK_MARK_AS_UNUSED RT_BIT_32(0)
+/** DVM flags - Space which is unused in the map will be marked as used
+ * when calling RTDvmMapQueryBlockStatus(). */
+#define DVM_FLAGS_UNUSED_SPACE_MARK_AS_USED RT_BIT_32(1)
+/** Mask of all valid flags. */
+#define DVM_FLAGS_VALID_MASK UINT32_C(0x00000003)
+/** @} */
+
+
+/** @defgroup grp_dvm_vol_flags Volume flags used by RTDvmVolumeGetFlags().
+ * @{ */
+/** Volume flags - Volume is bootable. */
+#define DVMVOLUME_FLAGS_BOOTABLE RT_BIT_64(0)
+/** Volume flags - Volume is active. */
+#define DVMVOLUME_FLAGS_ACTIVE RT_BIT_64(1)
+/** Volume is contiguous on the underlying medium and RTDvmVolumeQueryRange(). */
+#define DVMVOLUME_F_CONTIGUOUS RT_BIT_64(2)
+/** @} */
+
+/** A handle to a volume manager. */
+typedef struct RTDVMINTERNAL *RTDVM;
+/** A pointer to a volume manager handle. */
+typedef RTDVM *PRTDVM;
+/** NIL volume manager handle. */
+#define NIL_RTDVM ((RTDVM)~0)
+
+/** A handle to a volume in a volume map. */
+typedef struct RTDVMVOLUMEINTERNAL *RTDVMVOLUME;
+/** A pointer to a volume handle. */
+typedef RTDVMVOLUME *PRTDVMVOLUME;
+/** NIL volume handle. */
+#define NIL_RTDVMVOLUME ((RTDVMVOLUME)~0)
+
+/**
+ * Callback for querying the block allocation status of a volume.
+ *
+ * @returns IPRT status code.
+ * @param pvUser Opaque user data passed when setting the callback.
+ * @param off Offset relative to the start of the volume.
+ * @param cb Range to check in bytes.
+ * @param pfAllocated Where to store the allocation status on success.
+ */
+typedef DECLCALLBACKTYPE(int, FNDVMVOLUMEQUERYBLOCKSTATUS,(void *pvUser, uint64_t off, uint64_t cb, bool *pfAllocated));
+/** Pointer to a query block allocation status callback. */
+typedef FNDVMVOLUMEQUERYBLOCKSTATUS *PFNDVMVOLUMEQUERYBLOCKSTATUS;
+
+/**
+ * Create a new volume manager.
+ *
+ * @returns IPRT status.
+ * @param phVolMgr Where to store the handle to the volume manager on
+ * success.
+ * @param hVfsFile The disk/container/whatever.
+ * @param cbSector Size of one sector in bytes.
+ * @param fFlags Combination of RTDVM_FLAGS_*
+ */
+RTDECL(int) RTDvmCreate(PRTDVM phVolMgr, RTVFSFILE hVfsFile, uint32_t cbSector, uint32_t fFlags);
+
+/**
+ * Retain a given volume manager.
+ *
+ * @returns New reference count on success, UINT32_MAX on failure.
+ * @param hVolMgr The volume manager to retain.
+ */
+RTDECL(uint32_t) RTDvmRetain(RTDVM hVolMgr);
+
+/**
+ * Releases a given volume manager.
+ *
+ * @returns New reference count on success (0 if closed), UINT32_MAX on failure.
+ * @param hVolMgr The volume manager to release.
+ */
+RTDECL(uint32_t) RTDvmRelease(RTDVM hVolMgr);
+
+/**
+ * Probes the underyling disk for the best volume manager format handler
+ * and opens it.
+ *
+ * @returns IPRT status code.
+ * @retval VERR_NOT_FOUND if no backend can handle the volume map on the disk.
+ * @param hVolMgr The volume manager handle.
+ */
+RTDECL(int) RTDvmMapOpen(RTDVM hVolMgr);
+
+/**
+ * Initializes a new volume map using the given format handler.
+ *
+ * @returns IPRT status code.
+ * @param hVolMgr The volume manager handle.
+ * @param pszFmt The format to use for the new map.
+ */
+RTDECL(int) RTDvmMapInitialize(RTDVM hVolMgr, const char *pszFmt);
+
+/**
+ * Gets the name of the currently used format of the disk map.
+ *
+ * @returns Name of the format.
+ * @param hVolMgr The volume manager handle.
+ */
+RTDECL(const char *) RTDvmMapGetFormatName(RTDVM hVolMgr);
+
+/**
+ * DVM format types.
+ */
+typedef enum RTDVMFORMATTYPE
+{
+ /** Invalid zero value. */
+ RTDVMFORMATTYPE_INVALID = 0,
+ /** Master boot record. */
+ RTDVMFORMATTYPE_MBR,
+ /** GUID partition table. */
+ RTDVMFORMATTYPE_GPT,
+ /** BSD labels. */
+ RTDVMFORMATTYPE_BSD_LABEL,
+ /** End of valid values. */
+ RTDVMFORMATTYPE_END,
+ /** 32-bit type size hack. */
+ RTDVMFORMATTYPE_32BIT_HACK = 0x7fffffff
+} RTDVMFORMATTYPE;
+
+/**
+ * Gets the format type of the current disk map.
+ *
+ * @returns Format type. RTDVMFORMATTYPE_INVALID on invalid input.
+ * @param hVolMgr The volume manager handle.
+ */
+RTDECL(RTDVMFORMATTYPE) RTDvmMapGetFormatType(RTDVM hVolMgr);
+
+/**
+ * Gets the UUID of the disk if applicable.
+ *
+ * Disks using the MBR format may return the 32-bit disk identity in the
+ * u32TimeLow field and set the rest to zero.
+ *
+ * @returns IPRT status code.
+ * @retval VERR_NOT_SUPPORTED if the partition scheme doesn't do UUIDs.
+ * @retval VINF_NOT_SUPPORTED if non-UUID disk ID is returned.
+ * @param hVolMgr The volume manager handle.
+ * @param pUuid Where to return the UUID.
+ *
+ * @todo It's quite possible this should be turned into a map-level edition of
+ * RTDvmVolumeQueryProp...
+ */
+RTDECL(int) RTDvmMapQueryDiskUuid(RTDVM hVolMgr, PRTUUID pUuid);
+
+/**
+ * Gets the number of valid partitions in the map.
+ *
+ * @returns The number of valid volumes in the map or UINT32_MAX on failure.
+ * @param hVolMgr The volume manager handle.
+ */
+RTDECL(uint32_t) RTDvmMapGetValidVolumes(RTDVM hVolMgr);
+
+/**
+ * Gets the maximum number of partitions the map can hold.
+ *
+ * @returns The maximum number of volumes in the map or UINT32_MAX on failure.
+ * @param hVolMgr The volume manager handle.
+ */
+RTDECL(uint32_t) RTDvmMapGetMaxVolumes(RTDVM hVolMgr);
+
+/**
+ * Get the first valid volume from a map.
+ *
+ * @returns IPRT status code.
+ * @param hVolMgr The volume manager handle.
+ * @param phVol Where to store the handle to the first volume on
+ * success. Release with RTDvmVolumeRelease().
+ */
+RTDECL(int) RTDvmMapQueryFirstVolume(RTDVM hVolMgr, PRTDVMVOLUME phVol);
+
+/**
+ * Get the first valid volume from a map.
+ *
+ * @returns IPRT status code.
+ * @param hVolMgr The volume manager handle.
+ * @param hVol Handle of the current volume.
+ * @param phVolNext Where to store the handle to the next volume on
+ * success. Release with RTDvmVolumeRelease().
+ */
+RTDECL(int) RTDvmMapQueryNextVolume(RTDVM hVolMgr, RTDVMVOLUME hVol, PRTDVMVOLUME phVolNext);
+
+/**
+ * Returns whether the given block on the disk is in use.
+ *
+ * @returns IPRT status code.
+ * @param hVolMgr The volume manager handle.
+ * @param off The start offset to check for.
+ * @param cb The range in bytes to check.
+ * @param pfAllocated Where to store the in-use status on success.
+ *
+ * @remark This method will return true even if a part of the range is not in use.
+ */
+RTDECL(int) RTDvmMapQueryBlockStatus(RTDVM hVolMgr, uint64_t off, uint64_t cb, bool *pfAllocated);
+
+/**
+ * Partition/map table location information.
+ * @sa RTDvmMapQueryTableLocations
+ */
+typedef struct RTDVMTABLELOCATION
+{
+ /** The byte offset on the underlying media. */
+ uint64_t off;
+ /** The table size in bytes. */
+ uint64_t cb;
+ /** Number of padding bytes / free space between the actual table and
+ * first partition. */
+ uint64_t cbPadding;
+} RTDVMTABLELOCATION;
+/** Pointer to partition table location info. */
+typedef RTDVMTABLELOCATION *PRTDVMTABLELOCATION;
+/** Pointer to const partition table location info. */
+typedef RTDVMTABLELOCATION const *PCRTDVMTABLELOCATION;
+
+
+/** @name RTDVMMAPQTABLOC_F_XXX - Flags for RTDvmMapQueryTableLocations
+ * @{ */
+/** Make sure GPT includes the protective MBR. */
+#define RTDVMMAPQTABLOC_F_INCLUDE_LEGACY RT_BIT_32(0)
+/** Valid flags. */
+#define RTDVMMAPQTABLOC_F_VALID_MASK UINT32_C(1)
+/** @} */
+
+/**
+ * Query the partition table locations.
+ *
+ * @returns IPRT status code.
+ * @retval VERR_BUFFER_OVERFLOW if the table is too small, @a *pcActual will be
+ * set to the required size.
+ * @retval VERR_BUFFER_UNDERFLOW if the table is too big and @a pcActual is
+ * NULL.
+ * @param hVolMgr The volume manager handle.
+ * @param fFlags Flags, see RTDVMMAPQTABLOC_F_XXX.
+ * @param paLocations Where to return the info. This can be NULL if @a
+ * cLocations is zero and @a pcActual is given.
+ * @param cLocations The size of @a paLocations in items.
+ * @param pcActual Where to return the actual number of locations, or
+ * on VERR_BUFFER_OVERFLOW the necessary table size.
+ * Optional, when not specified the cLocations value
+ * must match exactly or it fails with
+ * VERR_BUFFER_UNDERFLOW.
+ */
+RTDECL(int) RTDvmMapQueryTableLocations(RTDVM hVolMgr, uint32_t fFlags,
+ PRTDVMTABLELOCATION paLocations, size_t cLocations, size_t *pcActual);
+
+/**
+ * Retains a valid volume handle.
+ *
+ * @returns New reference count on success, UINT32_MAX on failure.
+ * @param hVol The volume to retain.
+ */
+RTDECL(uint32_t) RTDvmVolumeRetain(RTDVMVOLUME hVol);
+
+/**
+ * Releases a valid volume handle.
+ *
+ * @returns New reference count on success (0 if closed), UINT32_MAX on failure.
+ * @param hVol The volume to release.
+ */
+RTDECL(uint32_t) RTDvmVolumeRelease(RTDVMVOLUME hVol);
+
+/**
+ * Sets the callback to query the block allocation status for a volume.
+ * This overwrites any other callback set previously.
+ *
+ * @param hVol The volume handle.
+ * @param pfnQueryBlockStatus The callback to set. Can be NULL to disable
+ * a previous callback.
+ * @param pvUser Opaque user data passed in the callback.
+ */
+RTDECL(void) RTDvmVolumeSetQueryBlockStatusCallback(RTDVMVOLUME hVol,
+ PFNDVMVOLUMEQUERYBLOCKSTATUS pfnQueryBlockStatus,
+ void *pvUser);
+
+/**
+ * Get the size of a volume in bytes.
+ *
+ * @returns Size of the volume in bytes or 0 on failure.
+ * @param hVol The volume handle.
+ */
+RTDECL(uint64_t) RTDvmVolumeGetSize(RTDVMVOLUME hVol);
+
+/**
+ * Gets the name of the volume if supported.
+ *
+ * @returns IPRT status code.
+ * @param hVol The volume handle.
+ * @param ppszVolName Where to store the name of the volume on success.
+ * The string must be freed with RTStrFree().
+ */
+RTDECL(int) RTDvmVolumeQueryName(RTDVMVOLUME hVol, char **ppszVolName);
+
+/**
+ * Get the volume type of the volume if supported.
+ *
+ * @returns The volume type on success, DVMVOLTYPE_INVALID if hVol is invalid.
+ * @param hVol The volume handle.
+ */
+RTDECL(RTDVMVOLTYPE) RTDvmVolumeGetType(RTDVMVOLUME hVol);
+
+/**
+ * Get the volume flags of the volume if supported.
+ *
+ * @returns The volume flags or UINT64_MAX on failure.
+ * @param hVol The volume handle.
+ */
+RTDECL(uint64_t) RTDvmVolumeGetFlags(RTDVMVOLUME hVol);
+
+/**
+ * Queries the range of the given volume on the underlying medium.
+ *
+ * @returns IPRT status code.
+ * @retval VERR_NOT_SUPPORTED if the DVMVOLUME_F_CONTIGUOUS flag is not returned by RTDvmVolumeGetFlags().
+ * @param hVol The volume handle.
+ * @param poffStart Where to store the start offset in bytes on the underlying medium.
+ * @param poffLast Where to store the last offset in bytes on the underlying medium (inclusive).
+ */
+RTDECL(int) RTDvmVolumeQueryRange(RTDVMVOLUME hVol, uint64_t *poffStart, uint64_t *poffLast);
+
+/**
+ * Returns the partition/whatever table location of the volume.
+ *
+ * For volume format with a single table, like GPT and BSD-labels, it will
+ * return the location of that table. Though for GPT, the fake MBR will not be
+ * included.
+ *
+ * For logical (extended) MBR-style volumes, this will return the location of
+ * the extended partition table. For primary volumes the MBR location is
+ * returned. The special MBR case is why this operation is done on the volume
+ * rather than the volume manager.
+ *
+ * Using RTDvmVolumeGetIndex with RTDVMVOLIDX_IN_PART_TABLE should get you
+ * the index in the table returned by this function.
+ *
+ * @returns IPRT status code.
+ * @param hVol The volume handle.
+ * @param poffTable Where to return the byte offset on the underlying
+ * media of the (partition/volume/whatever) table.
+ * @param pcbTable Where to return the table size in bytes. (This does
+ * not include any alignment padding or such, just
+ * padding up to sector/block size.)
+ */
+RTDECL(int) RTDvmVolumeQueryTableLocation(RTDVMVOLUME hVol, uint64_t *poffTable, uint64_t *pcbTable);
+
+/**
+ * RTDvmVolumeGetIndex indexes.
+ */
+typedef enum RTDVMVOLIDX
+{
+ /** Invalid zero value. */
+ RTDVMVOLIDX_INVALID = 0,
+ /** Index matching the host's volume numbering.
+ * This is a pseudo index, that gets translated to one of the others depending
+ * on which host we're running on. */
+ RTDVMVOLIDX_HOST,
+ /** Only consider user visible ones, i.e. don't count MBR extended partition
+ * entries and such like. */
+ RTDVMVOLIDX_USER_VISIBLE,
+ /** Index when all volumes, user visible, hidden, special, whatever ones are
+ * included.
+ *
+ * For MBR this is 1-based index where all primary entires are included whether
+ * in use or not. Only non-empty entries in extended tables are counted, though
+ * the forward link is included. */
+ RTDVMVOLIDX_ALL,
+ /** The raw index within the partition/volume/whatever table. This have a kind
+ * of special meaning to MBR, where there are multiple tables. */
+ RTDVMVOLIDX_IN_TABLE,
+ /** Follows the linux /dev/sdaX convention as closely as absolutely possible. */
+ RTDVMVOLIDX_LINUX,
+ /** End of valid indexes. */
+ RTDVMVOLIDX_END,
+ /** Make sure the type is 32-bit. */
+ RTDVMVOLIDX_32BIT_HACK = 0x7fffffff
+} RTDVMVOLIDX;
+
+/**
+ * Gets the tiven index for the specified volume.
+ *
+ * @returns The requested index, UINT32_MAX on failure.
+ * @param hVol The volume handle.
+ * @param enmIndex Which kind of index to get for the volume.
+ */
+RTDECL(uint32_t) RTDvmVolumeGetIndex(RTDVMVOLUME hVol, RTDVMVOLIDX enmIndex);
+
+/**
+ * Volume properties queriable via RTDvmVolumeQueryProp.
+ *
+ * @note Integer values can typically be queried in multiple sizes. This is
+ * handled by the frontend code. The format specific backends only
+ * have to handle the smallest allowed size.
+ */
+typedef enum RTDVMVOLPROP
+{
+ /** Customary invalid zero value. */
+ RTDVMVOLPROP_INVALID = 0,
+ /** unsigned[16,32,64]: MBR first cylinder (0-based, CHS). */
+ RTDVMVOLPROP_MBR_FIRST_CYLINDER,
+ /** unsigned[8,16,32,64]: MBR first head (0-based, CHS). */
+ RTDVMVOLPROP_MBR_FIRST_HEAD,
+ /** unsigned[8,16,32,64]: MBR first sector (1-based, CHS). */
+ RTDVMVOLPROP_MBR_FIRST_SECTOR,
+ /** unsigned[16,32,64]: MBR last cylinder (0-based, CHS). */
+ RTDVMVOLPROP_MBR_LAST_CYLINDER,
+ /** unsigned[8,16,32,64]: MBR last head (0-based, CHS). */
+ RTDVMVOLPROP_MBR_LAST_HEAD,
+ /** unsigned[8,16,32,64]: MBR last sector (1-based, CHS). */
+ RTDVMVOLPROP_MBR_LAST_SECTOR,
+ /** unsigned[8,16,32,64]: MBR partition type. */
+ RTDVMVOLPROP_MBR_TYPE,
+ /** RTUUID: GPT volume type. */
+ RTDVMVOLPROP_GPT_TYPE,
+ /** RTUUID: GPT volume UUID. */
+ RTDVMVOLPROP_GPT_UUID,
+ /** End of valid values. */
+ RTDVMVOLPROP_END,
+ /** Make sure the type is 32-bit. */
+ RTDVMVOLPROP_32BIT_HACK = 0x7fffffff
+} RTDVMVOLPROP;
+
+/**
+ * Query a generic volume property.
+ *
+ * This is an extensible interface for retrieving mostly format specific
+ * information, or information that's not commonly used. (It's modeled after
+ * RTLdrQueryPropEx.)
+ *
+ * @returns IPRT status code.
+ * @retval VERR_NOT_SUPPORTED if the property query isn't supported (either all
+ * or that specific property). The caller must handle this result.
+ * @retval VERR_NOT_FOUND is currently not returned, but intended for cases
+ * where it wasn't present in the tables.
+ * @retval VERR_INVALID_FUNCTION if the @a enmProperty value is wrong.
+ * @retval VERR_INVALID_PARAMETER if the fixed buffer size is wrong. Correct
+ * size in @a *pcbBuf.
+ * @retval VERR_BUFFER_OVERFLOW if the property doesn't have a fixed size
+ * buffer and the buffer isn't big enough. Correct size in @a *pcbBuf.
+ * @retval VERR_INVALID_HANDLE if the handle is invalid.
+ * @param hVol Handle to the volume.
+ * @param enmProperty The property to query.
+ * @param pvBuf Pointer to the input / output buffer. In most cases
+ * it's only used for returning data.
+ * @param cbBuf The size of the buffer.
+ * @param pcbBuf Where to return the amount of data returned. On
+ * buffer size errors, this is set to the correct size.
+ * Optional.
+ * @sa RTDvmVolumeGetPropU64
+ */
+RTDECL(int) RTDvmVolumeQueryProp(RTDVMVOLUME hVol, RTDVMVOLPROP enmProperty, void *pvBuf, size_t cbBuf, size_t *pcbBuf);
+
+/**
+ * Wrapper around RTDvmVolumeQueryProp for simplifying getting unimportant
+ * integer properties.
+ *
+ * @returns The property value if supported and found, the default value if not.
+ * Errors other than VERR_NOT_SUPPORTED and VERR_NOT_FOUND are
+ * asserted.
+ * @param hVol Handle to the volume.
+ * @param enmProperty The property to query.
+ * @param uDefault The value to return on error.
+ * @sa RTDvmVolumeQueryProp
+ */
+RTDECL(uint64_t) RTDvmVolumeGetPropU64(RTDVMVOLUME hVol, RTDVMVOLPROP enmProperty, uint64_t uDefault);
+
+/**
+ * Reads data from the given volume.
+ *
+ * @returns IPRT status code.
+ * @param hVol The volume handle.
+ * @param off Where to start reading from - 0 is the beginning of
+ * the volume.
+ * @param pvBuf Where to store the read data.
+ * @param cbRead How many bytes to read.
+ */
+RTDECL(int) RTDvmVolumeRead(RTDVMVOLUME hVol, uint64_t off, void *pvBuf, size_t cbRead);
+
+/**
+ * Writes data to the given volume.
+ *
+ * @returns IPRT status code.
+ * @param hVol The volume handle.
+ * @param off Where to start writing to - 0 is the beginning of
+ * the volume.
+ * @param pvBuf The data to write.
+ * @param cbWrite How many bytes to write.
+ */
+RTDECL(int) RTDvmVolumeWrite(RTDVMVOLUME hVol, uint64_t off, const void *pvBuf, size_t cbWrite);
+
+/**
+ * Returns the description of a given volume type.
+ *
+ * @returns The description of the type.
+ * @param enmVolType The volume type.
+ */
+RTDECL(const char *) RTDvmVolumeTypeGetDescr(RTDVMVOLTYPE enmVolType);
+
+/**
+ * Creates an VFS file from a volume handle.
+ *
+ * @returns IPRT status code.
+ * @param hVol The volume handle.
+ * @param fOpen RTFILE_O_XXX.
+ * @param phVfsFileOut Where to store the VFS file handle on success.
+ */
+RTDECL(int) RTDvmVolumeCreateVfsFile(RTDVMVOLUME hVol, uint64_t fOpen, PRTVFSFILE phVfsFileOut);
+
+RT_C_DECLS_END
+
+/** @} */
+
+#endif /* !IPRT_INCLUDED_dvm_h */
+