VHD.cpp@ 98103

Last change on this file since 98103 was 98103, checked in by vboxsync, 22 months ago
Copyright year updates by scm.
Property svn:eol-style set to `native` Property svn:keywords set to `Author Date Id Revision`
File size: 119.6 KB

Line
1	/* $Id: VHD.cpp 98103 2023-01-17 14:15:46Z vboxsync $ */
2	/** @file
3	* VHD Disk image, Core Code.
4	*/
5
6	/*
7	* Copyright (C) 2006-2023 Oracle and/or its affiliates.
8	*
9	* This file is part of VirtualBox base platform packages, as
10	* available from https://www.virtualbox.org.
11	*
12	* This program is free software; you can redistribute it and/or
13	* modify it under the terms of the GNU General Public License
14	* as published by the Free Software Foundation, in version 3 of the
15	* License.
16	*
17	* This program is distributed in the hope that it will be useful, but
18	* WITHOUT ANY WARRANTY; without even the implied warranty of
19	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
20	* General Public License for more details.
21	*
22	* You should have received a copy of the GNU General Public License
23	* along with this program; if not, see <https://www.gnu.org/licenses>.
24	*
25	* SPDX-License-Identifier: GPL-3.0-only
26	*/
27
28
29	/*********************************************************************************************************************************
30	* Header Files *
31	*********************************************************************************************************************************/
32	#define LOG_GROUP LOG_GROUP_VD_VHD
33	#include <VBox/vd-plugin.h>
34	#include <VBox/err.h>
35
36	#include <VBox/log.h>
37	#include <VBox/version.h>
38	#include <iprt/asm.h>
39	#include <iprt/assert.h>
40	#include <iprt/mem.h>
41	#include <iprt/uuid.h>
42	#include <iprt/path.h>
43	#include <iprt/string.h>
44	#include <iprt/utf16.h>
45
46	#include "VDBackends.h"
47
48	#define VHD_RELATIVE_MAX_PATH 512
49	#define VHD_ABSOLUTE_MAX_PATH 512
50
51	#define VHD_SECTOR_SIZE 512
52	#define VHD_BLOCK_SIZE (2 * _1M)
53
54	/** The maximum VHD size is 2TB due to the 32bit sector numbers in the BAT.
55	* Note that this is the maximum file size including all footers and headers
56	* and not the maximum virtual disk size presented to the guest.
57	*/
58	#define VHD_MAX_SIZE (2 * _1T)
59	/** Maximum number of 512 byte sectors for a VHD image. */
60	#define VHD_MAX_SECTORS (VHD_MAX_SIZE / VHD_SECTOR_SIZE)
61
62	/* This is common to all VHD disk types and is located at the end of the image */
63	#pragma pack(1)
64	typedef struct VHDFooter
65	{
66	char Cookie[8];
67	uint32_t Features;
68	uint32_t Version;
69	uint64_t DataOffset;
70	uint32_t Timestamp;
71	uint8_t CreatorApp[4];
72	uint32_t CreatorVer;
73	uint32_t CreatorOS;
74	uint64_t OrigSize;
75	uint64_t CurSize;
76	uint16_t DiskGeometryCylinder;
77	uint8_t DiskGeometryHeads;
78	uint8_t DiskGeometrySectors;
79	uint32_t DiskType;
80	uint32_t Checksum;
81	char UniqueID[16];
82	uint8_t SavedState;
83	uint8_t Reserved[427];
84	} VHDFooter;
85	#pragma pack()
86
87	/* this really is spelled with only one n */
88	#define VHD_FOOTER_COOKIE "conectix"
89	#define VHD_FOOTER_COOKIE_SIZE 8
90
91	#define VHD_FOOTER_FEATURES_NOT_ENABLED 0
92	#define VHD_FOOTER_FEATURES_TEMPORARY 1
93	#define VHD_FOOTER_FEATURES_RESERVED 2
94
95	#define VHD_FOOTER_FILE_FORMAT_VERSION 0x00010000
96	#define VHD_FOOTER_DATA_OFFSET_FIXED UINT64_C(0xffffffffffffffff)
97	#define VHD_FOOTER_DISK_TYPE_FIXED 2
98	#define VHD_FOOTER_DISK_TYPE_DYNAMIC 3
99	#define VHD_FOOTER_DISK_TYPE_DIFFERENCING 4
100
101	#define VHD_MAX_LOCATOR_ENTRIES 8
102	#define VHD_PLATFORM_CODE_NONE 0
103	#define VHD_PLATFORM_CODE_WI2R 0x57693272
104	#define VHD_PLATFORM_CODE_WI2K 0x5769326B
105	#define VHD_PLATFORM_CODE_W2RU 0x57327275
106	#define VHD_PLATFORM_CODE_W2KU 0x57326B75
107	#define VHD_PLATFORM_CODE_MAC 0x4D163220
108	#define VHD_PLATFORM_CODE_MACX 0x4D163258
109
110	/* Header for expanding disk images. */
111	#pragma pack(1)
112	typedef struct VHDParentLocatorEntry
113	{
114	uint32_t u32Code;
115	uint32_t u32DataSpace;
116	uint32_t u32DataLength;
117	uint32_t u32Reserved;
118	uint64_t u64DataOffset;
119	} VHDPLE, *PVHDPLE;
120
121	typedef struct VHDDynamicDiskHeader
122	{
123	char Cookie[8];
124	uint64_t DataOffset;
125	uint64_t TableOffset;
126	uint32_t HeaderVersion;
127	uint32_t MaxTableEntries;
128	uint32_t BlockSize;
129	uint32_t Checksum;
130	uint8_t ParentUuid[16];
131	uint32_t ParentTimestamp;
132	uint32_t Reserved0;
133	uint16_t ParentUnicodeName[256];
134	VHDPLE ParentLocatorEntry[VHD_MAX_LOCATOR_ENTRIES];
135	uint8_t Reserved1[256];
136	} VHDDynamicDiskHeader;
137	#pragma pack()
138
139	#define VHD_DYNAMIC_DISK_HEADER_COOKIE "cxsparse"
140	#define VHD_DYNAMIC_DISK_HEADER_COOKIE_SIZE 8
141	#define VHD_DYNAMIC_DISK_HEADER_VERSION 0x00010000
142
143	/**
144	* Complete VHD image data structure.
145	*/
146	typedef struct VHDIMAGE
147	{
148	/** Image file name. */
149	const char *pszFilename;
150	/** Opaque storage handle. */
151	PVDIOSTORAGE pStorage;
152
153	/** Pointer to the per-disk VD interface list. */
154	PVDINTERFACE pVDIfsDisk;
155	/** Pointer to the per-image VD interface list. */
156	PVDINTERFACE pVDIfsImage;
157	/** Error interface. */
158	PVDINTERFACEERROR pIfError;
159	/** I/O interface. */
160	PVDINTERFACEIOINT pIfIo;
161
162	/** Open flags passed by VBoxHDD layer. */
163	unsigned uOpenFlags;
164	/** Image flags defined during creation or determined during open. */
165	unsigned uImageFlags;
166	/** Total size of the image. */
167	uint64_t cbSize;
168
169	/** Physical geometry of this image. */
170	VDGEOMETRY PCHSGeometry;
171	/** Logical geometry of this image. */
172	VDGEOMETRY LCHSGeometry;
173
174	/** Image UUID. */
175	RTUUID ImageUuid;
176	/** Parent image UUID. */
177	RTUUID ParentUuid;
178
179	/** Parent's time stamp at the time of image creation. */
180	uint32_t u32ParentTimestamp;
181	/** Relative path to the parent image. */
182	char *pszParentFilename;
183
184	/** The Block Allocation Table. */
185	uint32_t *pBlockAllocationTable;
186	/** Number of entries in the table. */
187	uint32_t cBlockAllocationTableEntries;
188
189	/** Size of one data block. */
190	uint32_t cbDataBlock;
191	/** Sectors per data block. */
192	uint32_t cSectorsPerDataBlock;
193	/** Length of the sector bitmap in bytes. */
194	uint32_t cbDataBlockBitmap;
195	/** A copy of the disk footer. */
196	VHDFooter vhdFooterCopy;
197	/** Current end offset of the file (without the disk footer). */
198	uint64_t uCurrentEndOfFile;
199	/** Size of the data block bitmap in sectors. */
200	uint32_t cDataBlockBitmapSectors;
201	/** Start of the block allocation table. */
202	uint64_t uBlockAllocationTableOffset;
203	/** Buffer to hold block's bitmap for bit search operations. */
204	uint8_t *pu8Bitmap;
205	/** Offset to the next data structure (dynamic disk header). */
206	uint64_t u64DataOffset;
207	/** Flag to force dynamic disk header update. */
208	bool fDynHdrNeedsUpdate;
209	/** The static region list. */
210	VDREGIONLIST RegionList;
211	} VHDIMAGE, *PVHDIMAGE;
212
213	/**
214	* Structure tracking the expansion process of the image
215	* for async access.
216	*/
217	typedef struct VHDIMAGEEXPAND
218	{
219	/** Flag indicating the status of each step. */
220	volatile uint32_t fFlags;
221	/** The index in the block allocation table which is written. */
222	uint32_t idxBatAllocated;
223	/** Big endian representation of the block index
224	* which is written in the BAT. */
225	uint32_t idxBlockBe;
226	/** Old end of the file - used for rollback in case of an error. */
227	uint64_t cbEofOld;
228	/** Sector bitmap written to the new block - variable in size. */
229	uint8_t au8Bitmap[1];
230	} VHDIMAGEEXPAND, *PVHDIMAGEEXPAND;
231
232	/**
233	* Flag defines
234	*/
235	#define VHDIMAGEEXPAND_STEP_IN_PROGRESS (0x0)
236	#define VHDIMAGEEXPAND_STEP_FAILED (0x2)
237	#define VHDIMAGEEXPAND_STEP_SUCCESS (0x3)
238	/** All steps completed successfully. */
239	#define VHDIMAGEEXPAND_ALL_SUCCESS (0xff)
240	/** All steps completed (no success indicator) */
241	#define VHDIMAGEEXPAND_ALL_COMPLETE (0xaa)
242
243	/** Every status field has 2 bits so we can encode 4 steps in one byte. */
244	#define VHDIMAGEEXPAND_STATUS_MASK 0x03
245	#define VHDIMAGEEXPAND_BLOCKBITMAP_STATUS_SHIFT 0x00
246	#define VHDIMAGEEXPAND_USERBLOCK_STATUS_SHIFT 0x02
247	#define VHDIMAGEEXPAND_FOOTER_STATUS_SHIFT 0x04
248	#define VHDIMAGEEXPAND_BAT_STATUS_SHIFT 0x06
249
250	/**
251	* Helper macros to get and set the status field.
252	*/
253	#define VHDIMAGEEXPAND_STATUS_GET(fFlags, cShift) \
254	(((fFlags) >> (cShift)) & VHDIMAGEEXPAND_STATUS_MASK)
255	#define VHDIMAGEEXPAND_STATUS_SET(fFlags, cShift, uVal) \
256	ASMAtomicOrU32(&(fFlags), ((uVal) & VHDIMAGEEXPAND_STATUS_MASK) << (cShift))
257
258
259	/*********************************************************************************************************************************
260	* Static Variables *
261	*********************************************************************************************************************************/
262
263	/** NULL-terminated array of supported file extensions. */
264	static const VDFILEEXTENSION s_aVhdFileExtensions[] =
265	{
266	{"vhd", VDTYPE_HDD},
267	{NULL, VDTYPE_INVALID}
268	};
269
270
271	/*********************************************************************************************************************************
272	* Internal Functions *
273	*********************************************************************************************************************************/
274
275
276	/**
277	* Internal: Compute and update header checksum.
278	*/
279	static uint32_t vhdChecksum(void *pHeader, uint32_t cbSize)
280	{
281	uint32_t u32ChkSum = 0;
282	for (uint32_t i = 0; i < cbSize; i++)
283	u32ChkSum += ((unsigned char *)pHeader)[i];
284	return ~u32ChkSum;
285	}
286
287	/**
288	* Internal: Convert filename to UTF16 with appropriate endianness.
289	*/
290	static int vhdFilenameToUtf16(const char pszFilename, uint16_t pu16Buf,
291	uint32_t cbBufSize, uint32_t *pcbActualSize,
292	bool fBigEndian)
293	{
294	int rc;
295	PRTUTF16 pTmp16 = NULL;
296	size_t cTmp16Len;
297
298	rc = RTStrToUtf16(pszFilename, &pTmp16);
299	if (RT_SUCCESS(rc))
300	{
301	cTmp16Len = RTUtf16Len(pTmp16);
302	if (cTmp16Len * sizeof(*pTmp16) <= cbBufSize)
303	{
304	if (fBigEndian)
305	for (unsigned i = 0; i < cTmp16Len; i++)
306	pu16Buf[i] = RT_H2BE_U16(pTmp16[i]);
307	else
308	memcpy(pu16Buf, pTmp16, cTmp16Len * sizeof(*pTmp16));
309	if (pcbActualSize)
310	pcbActualSize = (uint32_t)(cTmp16Len sizeof(*pTmp16));
311	}
312	else
313	rc = VERR_FILENAME_TOO_LONG;
314	}
315
316	if (pTmp16)
317	RTUtf16Free(pTmp16);
318	return rc;
319	}
320
321	/**
322	* Internal: Update one locator entry.
323	*/
324	static int vhdLocatorUpdate(PVHDIMAGE pImage, PVHDPLE pLocator, const char *pszFilename)
325	{
326	int rc = VINF_SUCCESS;
327	uint32_t cb = 0;
328	uint32_t cbMaxLen = RT_BE2H_U32(pLocator->u32DataSpace);
329	void *pvBuf = RTMemTmpAllocZ(cbMaxLen);
330	char *pszTmp;
331
332	if (!pvBuf)
333	return VERR_NO_MEMORY;
334
335	switch (RT_BE2H_U32(pLocator->u32Code))
336	{
337	case VHD_PLATFORM_CODE_WI2R:
338	{
339	if (RTPathStartsWithRoot(pszFilename))
340	{
341	/* Convert to relative path. */
342	char szPath[RTPATH_MAX];
343	rc = RTPathCalcRelative(szPath, sizeof(szPath), pImage->pszFilename, true /fFromFile/, pszFilename);
344	if (RT_SUCCESS(rc))
345	{
346	/* Update plain relative name. */
347	cb = (uint32_t)strlen(szPath);
348	if (cb > cbMaxLen)
349	{
350	rc = VERR_FILENAME_TOO_LONG;
351	break;
352	}
353	memcpy(pvBuf, szPath, cb);
354	}
355	}
356	else
357	{
358	/* Update plain relative name. */
359	cb = (uint32_t)strlen(pszFilename);
360	if (cb > cbMaxLen)
361	{
362	rc = VERR_FILENAME_TOO_LONG;
363	break;
364	}
365	memcpy(pvBuf, pszFilename, cb);
366	}
367	if (RT_SUCCESS(rc))
368	pLocator->u32DataLength = RT_H2BE_U32(cb);
369	break;
370	}
371	case VHD_PLATFORM_CODE_WI2K:
372	/* Update plain absolute name. */
373	rc = RTPathAbs(pszFilename, (char *)pvBuf, cbMaxLen);
374	if (RT_SUCCESS(rc))
375	{
376	cb = (uint32_t)strlen((const char *)pvBuf);
377	pLocator->u32DataLength = RT_H2BE_U32(cb);
378	}
379	break;
380	case VHD_PLATFORM_CODE_W2RU:
381	if (RTPathStartsWithRoot(pszFilename))
382	{
383	/* Convert to relative path. */
384	char szPath[RTPATH_MAX];
385	rc = RTPathCalcRelative(szPath, sizeof(szPath), pImage->pszFilename, true /fFromFile/, pszFilename);
386	if (RT_SUCCESS(rc))
387	rc = vhdFilenameToUtf16(szPath, (uint16_t *)pvBuf, cbMaxLen, &cb, false);
388	}
389	else
390	{
391	/* Update unicode relative name. */
392	rc = vhdFilenameToUtf16(pszFilename, (uint16_t *)pvBuf, cbMaxLen, &cb, false);
393	}
394
395	if (RT_SUCCESS(rc))
396	pLocator->u32DataLength = RT_H2BE_U32(cb);
397	break;
398	case VHD_PLATFORM_CODE_W2KU:
399	/* Update unicode absolute name. */
400	pszTmp = (char*)RTMemTmpAllocZ(cbMaxLen);
401	if (!pszTmp)
402	{
403	rc = VERR_NO_MEMORY;
404	break;
405	}
406	rc = RTPathAbs(pszFilename, pszTmp, cbMaxLen);
407	if (RT_FAILURE(rc))
408	{
409	RTMemTmpFree(pszTmp);
410	break;
411	}
412	rc = vhdFilenameToUtf16(pszTmp, (uint16_t *)pvBuf, cbMaxLen, &cb, false);
413	RTMemTmpFree(pszTmp);
414	if (RT_SUCCESS(rc))
415	pLocator->u32DataLength = RT_H2BE_U32(cb);
416	break;
417	default:
418	rc = VERR_NOT_IMPLEMENTED;
419	break;
420	}
421
422	if (RT_SUCCESS(rc))
423	{
424	Assert(cb > 0);
425	rc = vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage,
426	RT_BE2H_U64(pLocator->u64DataOffset),
427	pvBuf, cb);
428	}
429
430	if (pvBuf)
431	RTMemTmpFree(pvBuf);
432	return rc;
433	}
434
435	/**
436	* Internal: Update dynamic disk header from VHDIMAGE.
437	*/
438	static int vhdDynamicHeaderUpdate(PVHDIMAGE pImage)
439	{
440	VHDDynamicDiskHeader ddh;
441	int rc, i;
442
443	if (!pImage)
444	return VERR_VD_NOT_OPENED;
445
446	rc = vdIfIoIntFileReadSync(pImage->pIfIo, pImage->pStorage,
447	pImage->u64DataOffset, &ddh, sizeof(ddh));
448	if (RT_FAILURE(rc))
449	return rc;
450	if (memcmp(ddh.Cookie, VHD_DYNAMIC_DISK_HEADER_COOKIE, VHD_DYNAMIC_DISK_HEADER_COOKIE_SIZE) != 0)
451	return VERR_VD_VHD_INVALID_HEADER;
452
453	uint32_t u32Checksum = RT_BE2H_U32(ddh.Checksum);
454	ddh.Checksum = 0;
455	if (u32Checksum != vhdChecksum(&ddh, sizeof(ddh)))
456	return VERR_VD_VHD_INVALID_HEADER;
457
458	/* Update parent's timestamp. */
459	ddh.ParentTimestamp = RT_H2BE_U32(pImage->u32ParentTimestamp);
460	/* Update parent's filename. */
461	if (pImage->pszParentFilename)
462	{
463	rc = vhdFilenameToUtf16(RTPathFilename(pImage->pszParentFilename),
464	ddh.ParentUnicodeName, sizeof(ddh.ParentUnicodeName) - 1, NULL, true);
465	if (RT_FAILURE(rc))
466	return rc;
467	}
468
469	/* Update parent's locators. */
470	for (i = 0; i < VHD_MAX_LOCATOR_ENTRIES; i++)
471	{
472	/* Skip empty locators */
473	if ( ddh.ParentLocatorEntry[i].u32Code != RT_H2BE_U32(VHD_PLATFORM_CODE_NONE)
474	&& pImage->pszParentFilename)
475	{
476	rc = vhdLocatorUpdate(pImage, &ddh.ParentLocatorEntry[i], pImage->pszParentFilename);
477	if (RT_FAILURE(rc))
478	return rc;
479	}
480	}
481	/* Update parent's UUID */
482	memcpy(ddh.ParentUuid, pImage->ParentUuid.au8, sizeof(ddh.ParentUuid));
483
484	/* Update data offset and number of table entries. */
485	ddh.MaxTableEntries = RT_H2BE_U32(pImage->cBlockAllocationTableEntries);
486
487	ddh.Checksum = 0;
488	ddh.Checksum = RT_H2BE_U32(vhdChecksum(&ddh, sizeof(ddh)));
489	rc = vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage,
490	pImage->u64DataOffset, &ddh, sizeof(ddh));
491	return rc;
492	}
493
494	/**
495	* Internal: Update the VHD footer.
496	*/
497	static int vhdUpdateFooter(PVHDIMAGE pImage)
498	{
499	int rc = VINF_SUCCESS;
500
501	/* Update fields which can change. */
502	pImage->vhdFooterCopy.CurSize = RT_H2BE_U64(pImage->cbSize);
503	pImage->vhdFooterCopy.DiskGeometryCylinder = RT_H2BE_U16(pImage->PCHSGeometry.cCylinders);
504	pImage->vhdFooterCopy.DiskGeometryHeads = pImage->PCHSGeometry.cHeads;
505	pImage->vhdFooterCopy.DiskGeometrySectors = pImage->PCHSGeometry.cSectors;
506
507	pImage->vhdFooterCopy.Checksum = 0;
508	pImage->vhdFooterCopy.Checksum = RT_H2BE_U32(vhdChecksum(&pImage->vhdFooterCopy, sizeof(VHDFooter)));
509
510	if (pImage->pBlockAllocationTable)
511	rc = vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage, 0,
512	&pImage->vhdFooterCopy, sizeof(VHDFooter));
513
514	if (RT_SUCCESS(rc))
515	rc = vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage,
516	pImage->uCurrentEndOfFile, &pImage->vhdFooterCopy,
517	sizeof(VHDFooter));
518
519	return rc;
520	}
521
522	/**
523	* Internal. Flush image data to disk.
524	*/
525	static int vhdFlushImage(PVHDIMAGE pImage)
526	{
527	int rc = VINF_SUCCESS;
528
529	if (pImage->uOpenFlags & VD_OPEN_FLAGS_READONLY)
530	return VINF_SUCCESS;
531
532	if (pImage->pBlockAllocationTable)
533	{
534	/*
535	* This is an expanding image. Write the BAT and copy of the disk footer.
536	*/
537	size_t cbBlockAllocationTableToWrite = pImage->cBlockAllocationTableEntries * sizeof(uint32_t);
538	uint32_t pBlockAllocationTableToWrite = (uint32_t )RTMemAllocZ(cbBlockAllocationTableToWrite);
539
540	if (!pBlockAllocationTableToWrite)
541	return VERR_NO_MEMORY;
542
543	/*
544	* The BAT entries have to be stored in big endian format.
545	*/
546	for (unsigned i = 0; i < pImage->cBlockAllocationTableEntries; i++)
547	pBlockAllocationTableToWrite[i] = RT_H2BE_U32(pImage->pBlockAllocationTable[i]);
548
549	/*
550	* Write the block allocation table after the copy of the disk footer and the dynamic disk header.
551	*/
552	vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage, pImage->uBlockAllocationTableOffset,
553	pBlockAllocationTableToWrite, cbBlockAllocationTableToWrite);
554	if (pImage->fDynHdrNeedsUpdate)
555	rc = vhdDynamicHeaderUpdate(pImage);
556	RTMemFree(pBlockAllocationTableToWrite);
557	}
558
559	if (RT_SUCCESS(rc))
560	rc = vhdUpdateFooter(pImage);
561
562	if (RT_SUCCESS(rc))
563	rc = vdIfIoIntFileFlushSync(pImage->pIfIo, pImage->pStorage);
564
565	return rc;
566	}
567
568	/**
569	* Internal. Free all allocated space for representing an image except pImage,
570	* and optionally delete the image from disk.
571	*/
572	static int vhdFreeImage(PVHDIMAGE pImage, bool fDelete)
573	{
574	int rc = VINF_SUCCESS;
575
576	/* Freeing a never allocated image (e.g. because the open failed) is
577	* not signalled as an error. After all nothing bad happens. */
578	if (pImage)
579	{
580	if (pImage->pStorage)
581	{
582	/* No point updating the file that is deleted anyway. */
583	if (!fDelete)
584	vhdFlushImage(pImage);
585
586	rc = vdIfIoIntFileClose(pImage->pIfIo, pImage->pStorage);
587	pImage->pStorage = NULL;
588	}
589
590	if (pImage->pszParentFilename)
591	{
592	RTStrFree(pImage->pszParentFilename);
593	pImage->pszParentFilename = NULL;
594	}
595	if (pImage->pBlockAllocationTable)
596	{
597	RTMemFree(pImage->pBlockAllocationTable);
598	pImage->pBlockAllocationTable = NULL;
599	}
600	if (pImage->pu8Bitmap)
601	{
602	RTMemFree(pImage->pu8Bitmap);
603	pImage->pu8Bitmap = NULL;
604	}
605
606	if (fDelete && pImage->pszFilename)
607	{
608	int rc2 = vdIfIoIntFileDelete(pImage->pIfIo, pImage->pszFilename);
609	if (RT_SUCCESS(rc))
610	rc = rc2;
611	}
612	}
613
614	LogFlowFunc(("returns %Rrc\n", rc));
615	return rc;
616	}
617
618	/* 946684800 is the number of seconds between 1/1/1970 and 1/1/2000 */
619	#define VHD_TO_UNIX_EPOCH_SECONDS UINT64_C(946684800)
620
621	static uint32_t vhdRtTime2VhdTime(PCRTTIMESPEC pRtTimestamp)
622	{
623	uint64_t u64Seconds = RTTimeSpecGetSeconds(pRtTimestamp);
624	return (uint32_t)(u64Seconds - VHD_TO_UNIX_EPOCH_SECONDS);
625	}
626
627	static void vhdTime2RtTime(PRTTIMESPEC pRtTimestamp, uint32_t u32VhdTimestamp)
628	{
629	RTTimeSpecSetSeconds(pRtTimestamp, VHD_TO_UNIX_EPOCH_SECONDS + u32VhdTimestamp);
630	}
631
632	/**
633	* Internal: Allocates the block bitmap rounding up to the next 32bit or 64bit boundary.
634	* Can be freed with RTMemFree. The memory is zeroed.
635	*/
636	DECLINLINE(uint8_t *)vhdBlockBitmapAllocate(PVHDIMAGE pImage)
637	{
638	#ifdef RT_ARCH_AMD64
639	return (uint8_t *)RTMemAllocZ(pImage->cbDataBlockBitmap + 8);
640	#else
641	return (uint8_t *)RTMemAllocZ(pImage->cbDataBlockBitmap + 4);
642	#endif
643	}
644
645	/**
646	* Internal: called when the async expansion process completed (failure or success).
647	* Will do the necessary rollback if an error occurred.
648	*/
649	static int vhdAsyncExpansionComplete(PVHDIMAGE pImage, PVDIOCTX pIoCtx, PVHDIMAGEEXPAND pExpand)
650	{
651	int rc = VINF_SUCCESS;
652	uint32_t fFlags = ASMAtomicReadU32(&pExpand->fFlags);
653	bool fIoInProgress = false;
654
655	/* Quick path, check if everything succeeded. */
656	if (fFlags == VHDIMAGEEXPAND_ALL_SUCCESS)
657	{
658	pImage->pBlockAllocationTable[pExpand->idxBatAllocated] = RT_BE2H_U32(pExpand->idxBlockBe);
659	RTMemFree(pExpand);
660	}
661	else
662	{
663	uint32_t uStatus;
664
665	uStatus = VHDIMAGEEXPAND_STATUS_GET(pExpand->fFlags, VHDIMAGEEXPAND_BAT_STATUS_SHIFT);
666	if ( uStatus == VHDIMAGEEXPAND_STEP_FAILED
667	\|\| uStatus == VHDIMAGEEXPAND_STEP_SUCCESS)
668	{
669	/* Undo and restore the old value. */
670	pImage->pBlockAllocationTable[pExpand->idxBatAllocated] = ~0U;
671
672	/* Restore the old value on the disk.
673	* No need for a completion callback because we can't
674	* do anything if this fails. */
675	if (uStatus == VHDIMAGEEXPAND_STEP_SUCCESS)
676	{
677	rc = vdIfIoIntFileWriteMeta(pImage->pIfIo, pImage->pStorage,
678	pImage->uBlockAllocationTableOffset
679	+ pExpand->idxBatAllocated * sizeof(uint32_t),
680	&pImage->pBlockAllocationTable[pExpand->idxBatAllocated],
681	sizeof(uint32_t), pIoCtx, NULL, NULL);
682	fIoInProgress \|= rc == VERR_VD_ASYNC_IO_IN_PROGRESS;
683	}
684	}
685
686	/* Restore old size (including the footer because another application might
687	* fill up the free space making it impossible to add the footer)
688	* and add the footer at the right place again. */
689	rc = vdIfIoIntFileSetSize(pImage->pIfIo, pImage->pStorage,
690	pExpand->cbEofOld + sizeof(VHDFooter));
691	AssertRC(rc);
692
693	pImage->uCurrentEndOfFile = pExpand->cbEofOld;
694	rc = vdIfIoIntFileWriteMeta(pImage->pIfIo, pImage->pStorage,
695	pImage->uCurrentEndOfFile,
696	&pImage->vhdFooterCopy, sizeof(VHDFooter),
697	pIoCtx, NULL, NULL);
698	fIoInProgress \|= rc == VERR_VD_ASYNC_IO_IN_PROGRESS;
699	}
700
701	return fIoInProgress ? VERR_VD_ASYNC_IO_IN_PROGRESS : rc;
702	}
703
704	static int vhdAsyncExpansionStepCompleted(void pBackendData, PVDIOCTX pIoCtx, void pvUser, int rcReq, unsigned iStep)
705	{
706	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
707	PVHDIMAGEEXPAND pExpand = (PVHDIMAGEEXPAND)pvUser;
708
709	LogFlowFunc(("pBackendData=%#p pIoCtx=%#p pvUser=%#p rcReq=%Rrc iStep=%u\n",
710	pBackendData, pIoCtx, pvUser, rcReq, iStep));
711
712	if (RT_SUCCESS(rcReq))
713	VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, iStep, VHDIMAGEEXPAND_STEP_SUCCESS);
714	else
715	VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, iStep, VHDIMAGEEXPAND_STEP_FAILED);
716
717	if ((pExpand->fFlags & VHDIMAGEEXPAND_ALL_COMPLETE) == VHDIMAGEEXPAND_ALL_COMPLETE)
718	return vhdAsyncExpansionComplete(pImage, pIoCtx, pExpand);
719
720	return VERR_VD_ASYNC_IO_IN_PROGRESS;
721	}
722
723	static DECLCALLBACK(int) vhdAsyncExpansionDataBlockBitmapComplete(void pBackendData, PVDIOCTX pIoCtx, void pvUser, int rcReq)
724	{
725	return vhdAsyncExpansionStepCompleted(pBackendData, pIoCtx, pvUser, rcReq, VHDIMAGEEXPAND_BLOCKBITMAP_STATUS_SHIFT);
726	}
727
728	static DECLCALLBACK(int) vhdAsyncExpansionDataComplete(void pBackendData, PVDIOCTX pIoCtx, void pvUser, int rcReq)
729	{
730	return vhdAsyncExpansionStepCompleted(pBackendData, pIoCtx, pvUser, rcReq, VHDIMAGEEXPAND_USERBLOCK_STATUS_SHIFT);
731	}
732
733	static DECLCALLBACK(int) vhdAsyncExpansionBatUpdateComplete(void pBackendData, PVDIOCTX pIoCtx, void pvUser, int rcReq)
734	{
735	return vhdAsyncExpansionStepCompleted(pBackendData, pIoCtx, pvUser, rcReq, VHDIMAGEEXPAND_BAT_STATUS_SHIFT);
736	}
737
738	static DECLCALLBACK(int) vhdAsyncExpansionFooterUpdateComplete(void pBackendData, PVDIOCTX pIoCtx, void pvUser, int rcReq)
739	{
740	return vhdAsyncExpansionStepCompleted(pBackendData, pIoCtx, pvUser, rcReq, VHDIMAGEEXPAND_FOOTER_STATUS_SHIFT);
741	}
742
743	static int vhdLoadDynamicDisk(PVHDIMAGE pImage, uint64_t uDynamicDiskHeaderOffset)
744	{
745	VHDDynamicDiskHeader vhdDynamicDiskHeader;
746	int rc = VINF_SUCCESS;
747	uint32_t *pBlockAllocationTable;
748	uint64_t uBlockAllocationTableOffset;
749	unsigned i = 0;
750
751	Log(("Open a dynamic disk.\n"));
752
753	/*
754	* Read the dynamic disk header.
755	*/
756	rc = vdIfIoIntFileReadSync(pImage->pIfIo, pImage->pStorage, uDynamicDiskHeaderOffset,
757	&vhdDynamicDiskHeader, sizeof(VHDDynamicDiskHeader));
758	if (memcmp(vhdDynamicDiskHeader.Cookie, VHD_DYNAMIC_DISK_HEADER_COOKIE, VHD_DYNAMIC_DISK_HEADER_COOKIE_SIZE))
759	return VERR_INVALID_PARAMETER;
760
761	pImage->cbDataBlock = RT_BE2H_U32(vhdDynamicDiskHeader.BlockSize);
762	LogFlowFunc(("BlockSize=%u\n", pImage->cbDataBlock));
763	pImage->cBlockAllocationTableEntries = RT_BE2H_U32(vhdDynamicDiskHeader.MaxTableEntries);
764	LogFlowFunc(("MaxTableEntries=%lu\n", pImage->cBlockAllocationTableEntries));
765	AssertMsg(!(pImage->cbDataBlock % VHD_SECTOR_SIZE), ("%s: Data block size is not a multiple of %!\n", __FUNCTION__, VHD_SECTOR_SIZE));
766
767	/*
768	* Bail out if the number of BAT entries exceeds the number of sectors for a maximum image.
769	* Lower the number of sectors in the BAT as a few sectors are already occupied by the footers
770	* and headers.
771	*/
772	if (pImage->cBlockAllocationTableEntries > (VHD_MAX_SECTORS - 2))
773	return VERR_VD_VHD_INVALID_HEADER;
774
775	pImage->cSectorsPerDataBlock = pImage->cbDataBlock / VHD_SECTOR_SIZE;
776	LogFlowFunc(("SectorsPerDataBlock=%u\n", pImage->cSectorsPerDataBlock));
777
778	/*
779	* Every block starts with a bitmap indicating which sectors are valid and which are not.
780	* We store the size of it to be able to calculate the real offset.
781	*/
782	pImage->cbDataBlockBitmap = pImage->cSectorsPerDataBlock / 8;
783	pImage->cDataBlockBitmapSectors = pImage->cbDataBlockBitmap / VHD_SECTOR_SIZE;
784	/* Round up to full sector size */
785	if (pImage->cbDataBlockBitmap % VHD_SECTOR_SIZE > 0)
786	pImage->cDataBlockBitmapSectors++;
787	LogFlowFunc(("cbDataBlockBitmap=%u\n", pImage->cbDataBlockBitmap));
788	LogFlowFunc(("cDataBlockBitmapSectors=%u\n", pImage->cDataBlockBitmapSectors));
789
790	pImage->pu8Bitmap = vhdBlockBitmapAllocate(pImage);
791	if (!pImage->pu8Bitmap)
792	return VERR_NO_MEMORY;
793
794	pBlockAllocationTable = (uint32_t )RTMemAllocZ(pImage->cBlockAllocationTableEntries sizeof(uint32_t));
795	if (!pBlockAllocationTable)
796	return VERR_NO_MEMORY;
797
798	/*
799	* Read the table.
800	*/
801	uBlockAllocationTableOffset = RT_BE2H_U64(vhdDynamicDiskHeader.TableOffset);
802	LogFlowFunc(("uBlockAllocationTableOffset=%llu\n", uBlockAllocationTableOffset));
803	pImage->uBlockAllocationTableOffset = uBlockAllocationTableOffset;
804	rc = vdIfIoIntFileReadSync(pImage->pIfIo, pImage->pStorage,
805	uBlockAllocationTableOffset, pBlockAllocationTable,
806	pImage->cBlockAllocationTableEntries * sizeof(uint32_t));
807	if (RT_FAILURE(rc))
808	{
809	RTMemFree(pBlockAllocationTable);
810	return rc;
811	}
812
813	/*
814	* Because the offset entries inside the allocation table are stored big endian
815	* we need to convert them into host endian.
816	*/
817	pImage->pBlockAllocationTable = (uint32_t )RTMemAllocZ(pImage->cBlockAllocationTableEntries sizeof(uint32_t));
818	if (!pImage->pBlockAllocationTable)
819	{
820	RTMemFree(pBlockAllocationTable);
821	return VERR_NO_MEMORY;
822	}
823
824	for (i = 0; i < pImage->cBlockAllocationTableEntries; i++)
825	pImage->pBlockAllocationTable[i] = RT_BE2H_U32(pBlockAllocationTable[i]);
826
827	RTMemFree(pBlockAllocationTable);
828
829	if (pImage->uImageFlags & VD_IMAGE_FLAGS_DIFF)
830	memcpy(pImage->ParentUuid.au8, vhdDynamicDiskHeader.ParentUuid, sizeof(pImage->ParentUuid));
831
832	return rc;
833	}
834
835	static int vhdOpenImage(PVHDIMAGE pImage, unsigned uOpenFlags)
836	{
837	uint64_t FileSize;
838	VHDFooter vhdFooter;
839
840	pImage->uOpenFlags = uOpenFlags;
841
842	pImage->pIfError = VDIfErrorGet(pImage->pVDIfsDisk);
843	pImage->pIfIo = VDIfIoIntGet(pImage->pVDIfsImage);
844	AssertPtrReturn(pImage->pIfIo, VERR_INVALID_PARAMETER);
845
846	/*
847	* Open the image.
848	*/
849	int rc = vdIfIoIntFileOpen(pImage->pIfIo, pImage->pszFilename,
850	VDOpenFlagsToFileOpenFlags(uOpenFlags,
851	false /* fCreate */),
852	&pImage->pStorage);
853	if (RT_FAILURE(rc))
854	{
855	/* Do NOT signal an appropriate error here, as the VD layer has the
856	* choice of retrying the open if it failed. */
857	return rc;
858	}
859
860	rc = vdIfIoIntFileGetSize(pImage->pIfIo, pImage->pStorage, &FileSize);
861	pImage->uCurrentEndOfFile = FileSize - sizeof(VHDFooter);
862
863	rc = vdIfIoIntFileReadSync(pImage->pIfIo, pImage->pStorage, pImage->uCurrentEndOfFile,
864	&vhdFooter, sizeof(VHDFooter));
865	if (RT_SUCCESS(rc))
866	{
867	if (memcmp(vhdFooter.Cookie, VHD_FOOTER_COOKIE, VHD_FOOTER_COOKIE_SIZE) != 0)
868	{
869	/*
870	* There is also a backup header at the beginning in case the image got corrupted.
871	* Such corrupted images are detected here to let the open handler repair it later.
872	*/
873	rc = vdIfIoIntFileReadSync(pImage->pIfIo, pImage->pStorage, 0,
874	&vhdFooter, sizeof(VHDFooter));
875	if (RT_SUCCESS(rc))
876	{
877	if (memcmp(vhdFooter.Cookie, VHD_FOOTER_COOKIE, VHD_FOOTER_COOKIE_SIZE) != 0)
878	rc = VERR_VD_VHD_INVALID_HEADER;
879	else
880	rc = VERR_VD_IMAGE_CORRUPTED;
881	}
882	}
883	}
884
885	if (RT_FAILURE(rc))
886	{
887	vhdFreeImage(pImage, false);
888	return rc;
889	}
890
891	switch (RT_BE2H_U32(vhdFooter.DiskType))
892	{
893	case VHD_FOOTER_DISK_TYPE_FIXED:
894	pImage->uImageFlags \|= VD_IMAGE_FLAGS_FIXED;
895	break;
896	case VHD_FOOTER_DISK_TYPE_DYNAMIC:
897	pImage->uImageFlags &= ~VD_IMAGE_FLAGS_FIXED;
898	break;
899	case VHD_FOOTER_DISK_TYPE_DIFFERENCING:
900	pImage->uImageFlags \|= VD_IMAGE_FLAGS_DIFF;
901	pImage->uImageFlags &= ~VD_IMAGE_FLAGS_FIXED;
902	break;
903	default:
904	vhdFreeImage(pImage, false);
905	return VERR_NOT_IMPLEMENTED;
906	}
907
908	pImage->cbSize = RT_BE2H_U64(vhdFooter.CurSize);
909	pImage->LCHSGeometry.cCylinders = 0;
910	pImage->LCHSGeometry.cHeads = 0;
911	pImage->LCHSGeometry.cSectors = 0;
912	pImage->PCHSGeometry.cCylinders = RT_BE2H_U16(vhdFooter.DiskGeometryCylinder);
913	pImage->PCHSGeometry.cHeads = vhdFooter.DiskGeometryHeads;
914	pImage->PCHSGeometry.cSectors = vhdFooter.DiskGeometrySectors;
915
916	/*
917	* Copy of the disk footer.
918	* If we allocate new blocks in differencing disks on write access
919	* the footer is overwritten. We need to write it at the end of the file.
920	*/
921	memcpy(&pImage->vhdFooterCopy, &vhdFooter, sizeof(VHDFooter));
922
923	/*
924	* Is there a better way?
925	*/
926	memcpy(&pImage->ImageUuid, &vhdFooter.UniqueID, 16);
927
928	pImage->u64DataOffset = RT_BE2H_U64(vhdFooter.DataOffset);
929	LogFlowFunc(("DataOffset=%llu\n", pImage->u64DataOffset));
930
931	if (!(pImage->uImageFlags & VD_IMAGE_FLAGS_FIXED))
932	rc = vhdLoadDynamicDisk(pImage, pImage->u64DataOffset);
933
934	if (RT_SUCCESS(rc))
935	{
936	PVDREGIONDESC pRegion = &pImage->RegionList.aRegions[0];
937	pImage->RegionList.fFlags = 0;
938	pImage->RegionList.cRegions = 1;
939
940	pRegion->offRegion = 0; /* Disk start. */
941	pRegion->cbBlock = 512;
942	pRegion->enmDataForm = VDREGIONDATAFORM_RAW;
943	pRegion->enmMetadataForm = VDREGIONMETADATAFORM_NONE;
944	pRegion->cbData = 512;
945	pRegion->cbMetadata = 0;
946	pRegion->cRegionBlocksOrBytes = pImage->cbSize;
947	}
948	else
949	vhdFreeImage(pImage, false);
950	return rc;
951	}
952
953	/**
954	* Internal: Checks if a sector in the block bitmap is set
955	*/
956	DECLINLINE(bool) vhdBlockBitmapSectorContainsData(PVHDIMAGE pImage, uint32_t cBlockBitmapEntry)
957	{
958	uint32_t iBitmap = (cBlockBitmapEntry / 8); /* Byte in the block bitmap. */
959
960	/*
961	* The index of the bit in the byte of the data block bitmap.
962	* The most significant bit stands for a lower sector number.
963	*/
964	uint8_t iBitInByte = (8-1) - (cBlockBitmapEntry % 8);
965	uint8_t *puBitmap = pImage->pu8Bitmap + iBitmap;
966
967	AssertMsg(puBitmap < (pImage->pu8Bitmap + pImage->cbDataBlockBitmap),
968	("VHD: Current bitmap position exceeds maximum size of the bitmap\n"));
969
970	return ((*puBitmap) & RT_BIT(iBitInByte)) != 0;
971	}
972
973	/**
974	* Internal: Sets the given sector in the sector bitmap.
975	*/
976	DECLINLINE(bool) vhdBlockBitmapSectorSet(PVHDIMAGE pImage, uint8_t *pu8Bitmap, uint32_t cBlockBitmapEntry)
977	{
978	RT_NOREF1(pImage);
979	uint32_t iBitmap = (cBlockBitmapEntry / 8); /* Byte in the block bitmap. */
980
981	/*
982	* The index of the bit in the byte of the data block bitmap.
983	* The most significant bit stands for a lower sector number.
984	*/
985	uint8_t iBitInByte = (8-1) - (cBlockBitmapEntry % 8);
986	uint8_t *puBitmap = pu8Bitmap + iBitmap;
987
988	AssertMsg(puBitmap < (pu8Bitmap + pImage->cbDataBlockBitmap),
989	("VHD: Current bitmap position exceeds maximum size of the bitmap\n"));
990
991	bool fClear = ((*puBitmap) & RT_BIT(iBitInByte)) == 0;
992	*puBitmap \|= RT_BIT(iBitInByte);
993	return fClear;
994	}
995
996	/**
997	* Internal: Derive drive geometry from its size.
998	*/
999	static void vhdSetDiskGeometry(PVHDIMAGE pImage, uint64_t cbSize)
1000	{
1001	uint64_t u64TotalSectors = cbSize / VHD_SECTOR_SIZE;
1002	uint32_t u32CylinderTimesHeads, u32Heads, u32SectorsPerTrack;
1003
1004	if (u64TotalSectors > 65535 * 16 * 255)
1005	{
1006	/* ATA disks limited to 127 GB. */
1007	u64TotalSectors = 65535 * 16 * 255;
1008	}
1009
1010	if (u64TotalSectors >= 65535 * 16 * 63)
1011	{
1012	u32SectorsPerTrack = 255;
1013	u32Heads = 16;
1014	u32CylinderTimesHeads = u64TotalSectors / u32SectorsPerTrack;
1015	}
1016	else
1017	{
1018	u32SectorsPerTrack = 17;
1019	u32CylinderTimesHeads = u64TotalSectors / u32SectorsPerTrack;
1020
1021	u32Heads = (u32CylinderTimesHeads + 1023) / 1024;
1022
1023	if (u32Heads < 4)
1024	{
1025	u32Heads = 4;
1026	}
1027	if (u32CylinderTimesHeads >= (u32Heads * 1024) \|\| u32Heads > 16)
1028	{
1029	u32SectorsPerTrack = 31;
1030	u32Heads = 16;
1031	u32CylinderTimesHeads = u64TotalSectors / u32SectorsPerTrack;
1032	}
1033	if (u32CylinderTimesHeads >= (u32Heads * 1024))
1034	{
1035	u32SectorsPerTrack = 63;
1036	u32Heads = 16;
1037	u32CylinderTimesHeads = u64TotalSectors / u32SectorsPerTrack;
1038	}
1039	}
1040	pImage->PCHSGeometry.cCylinders = u32CylinderTimesHeads / u32Heads;
1041	pImage->PCHSGeometry.cHeads = u32Heads;
1042	pImage->PCHSGeometry.cSectors = u32SectorsPerTrack;
1043	pImage->LCHSGeometry.cCylinders = 0;
1044	pImage->LCHSGeometry.cHeads = 0;
1045	pImage->LCHSGeometry.cSectors = 0;
1046	}
1047
1048
1049	static uint32_t vhdAllocateParentLocators(PVHDIMAGE pImage, VHDDynamicDiskHeader *pDDH, uint64_t u64Offset)
1050	{
1051	RT_NOREF1(pImage);
1052	PVHDPLE pLocator = pDDH->ParentLocatorEntry;
1053
1054	/*
1055	* The VHD spec states that the DataSpace field holds the number of sectors
1056	* required to store the parent locator path.
1057	* As it turned out VPC and Hyper-V store the amount of bytes reserved for the
1058	* path and not the number of sectors.
1059	*/
1060
1061	/* Unicode absolute Windows path. */
1062	pLocator->u32Code = RT_H2BE_U32(VHD_PLATFORM_CODE_W2KU);
1063	pLocator->u32DataSpace = RT_H2BE_U32(VHD_ABSOLUTE_MAX_PATH * sizeof(RTUTF16));
1064	pLocator->u64DataOffset = RT_H2BE_U64(u64Offset);
1065	pLocator++;
1066	u64Offset += VHD_ABSOLUTE_MAX_PATH * sizeof(RTUTF16);
1067	/* Unicode relative Windows path. */
1068	pLocator->u32Code = RT_H2BE_U32(VHD_PLATFORM_CODE_W2RU);
1069	pLocator->u32DataSpace = RT_H2BE_U32(VHD_RELATIVE_MAX_PATH * sizeof(RTUTF16));
1070	pLocator->u64DataOffset = RT_H2BE_U64(u64Offset);
1071	u64Offset += VHD_RELATIVE_MAX_PATH * sizeof(RTUTF16);
1072	return u64Offset;
1073	}
1074
1075	/**
1076	* Internal: Additional code for dynamic VHD image creation.
1077	*/
1078	static int vhdCreateDynamicImage(PVHDIMAGE pImage, uint64_t cbSize)
1079	{
1080	int rc;
1081	VHDDynamicDiskHeader DynamicDiskHeader;
1082	uint32_t u32BlockAllocationTableSectors;
1083	void *pvTmp = NULL;
1084
1085	memset(&DynamicDiskHeader, 0, sizeof(DynamicDiskHeader));
1086
1087	pImage->u64DataOffset = sizeof(VHDFooter);
1088	pImage->cbDataBlock = VHD_BLOCK_SIZE; /* 2 MB */
1089	pImage->cSectorsPerDataBlock = pImage->cbDataBlock / VHD_SECTOR_SIZE;
1090	pImage->cbDataBlockBitmap = pImage->cSectorsPerDataBlock / 8;
1091	pImage->cDataBlockBitmapSectors = pImage->cbDataBlockBitmap / VHD_SECTOR_SIZE;
1092	/* Align to sector boundary */
1093	if (pImage->cbDataBlockBitmap % VHD_SECTOR_SIZE > 0)
1094	pImage->cDataBlockBitmapSectors++;
1095	pImage->pu8Bitmap = vhdBlockBitmapAllocate(pImage);
1096	if (!pImage->pu8Bitmap)
1097	return vdIfError(pImage->pIfError, VERR_NO_MEMORY, RT_SRC_POS, N_("VHD: cannot allocate memory for bitmap storage"));
1098
1099	/* Initialize BAT. */
1100	pImage->uBlockAllocationTableOffset = (uint64_t)sizeof(VHDFooter) + sizeof(VHDDynamicDiskHeader);
1101	pImage->cBlockAllocationTableEntries = (uint32_t)((cbSize + pImage->cbDataBlock - 1) / pImage->cbDataBlock); /* Align table to the block size. */
1102	u32BlockAllocationTableSectors = (pImage->cBlockAllocationTableEntries * sizeof(uint32_t) + VHD_SECTOR_SIZE - 1) / VHD_SECTOR_SIZE;
1103	pImage->pBlockAllocationTable = (uint32_t )RTMemAllocZ(pImage->cBlockAllocationTableEntries sizeof(uint32_t));
1104	if (!pImage->pBlockAllocationTable)
1105	return vdIfError(pImage->pIfError, VERR_NO_MEMORY, RT_SRC_POS, N_("VHD: cannot allocate memory for BAT"));
1106
1107	for (unsigned i = 0; i < pImage->cBlockAllocationTableEntries; i++)
1108	{
1109	pImage->pBlockAllocationTable[i] = 0xFFFFFFFF; /* It is actually big endian. */
1110	}
1111
1112	/* Round up to the sector size. */
1113	if (pImage->uImageFlags & VD_IMAGE_FLAGS_DIFF) /* fix hyper-v unreadable error */
1114	pImage->uCurrentEndOfFile = vhdAllocateParentLocators(pImage, &DynamicDiskHeader,
1115	pImage->uBlockAllocationTableOffset + u32BlockAllocationTableSectors * VHD_SECTOR_SIZE);
1116	else
1117	pImage->uCurrentEndOfFile = pImage->uBlockAllocationTableOffset + u32BlockAllocationTableSectors * VHD_SECTOR_SIZE;
1118
1119	/* Set dynamic image size. */
1120	pvTmp = RTMemTmpAllocZ(pImage->uCurrentEndOfFile + sizeof(VHDFooter));
1121	if (!pvTmp)
1122	return vdIfError(pImage->pIfError, VERR_NO_MEMORY, RT_SRC_POS, N_("VHD: cannot set the file size for '%s'"), pImage->pszFilename);
1123
1124	rc = vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage, 0, pvTmp,
1125	pImage->uCurrentEndOfFile + sizeof(VHDFooter));
1126	if (RT_FAILURE(rc))
1127	{
1128	RTMemTmpFree(pvTmp);
1129	return vdIfError(pImage->pIfError, rc, RT_SRC_POS, N_("VHD: cannot set the file size for '%s'"), pImage->pszFilename);
1130	}
1131
1132	RTMemTmpFree(pvTmp);
1133
1134	/* Initialize and write the dynamic disk header. */
1135	memcpy(DynamicDiskHeader.Cookie, VHD_DYNAMIC_DISK_HEADER_COOKIE, sizeof(DynamicDiskHeader.Cookie));
1136	DynamicDiskHeader.DataOffset = UINT64_C(0xFFFFFFFFFFFFFFFF); /* Initially the disk has no data. */
1137	DynamicDiskHeader.TableOffset = RT_H2BE_U64(pImage->uBlockAllocationTableOffset);
1138	DynamicDiskHeader.HeaderVersion = RT_H2BE_U32(VHD_DYNAMIC_DISK_HEADER_VERSION);
1139	DynamicDiskHeader.BlockSize = RT_H2BE_U32(pImage->cbDataBlock);
1140	DynamicDiskHeader.MaxTableEntries = RT_H2BE_U32(pImage->cBlockAllocationTableEntries);
1141	/* Compute and update checksum. */
1142	DynamicDiskHeader.Checksum = 0;
1143	DynamicDiskHeader.Checksum = RT_H2BE_U32(vhdChecksum(&DynamicDiskHeader, sizeof(DynamicDiskHeader)));
1144
1145	rc = vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage, sizeof(VHDFooter),
1146	&DynamicDiskHeader, sizeof(DynamicDiskHeader));
1147	if (RT_FAILURE(rc))
1148	return vdIfError(pImage->pIfError, rc, RT_SRC_POS, N_("VHD: cannot write dynamic disk header to image '%s'"), pImage->pszFilename);
1149
1150	/* Write BAT. */
1151	rc = vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage, pImage->uBlockAllocationTableOffset,
1152	pImage->pBlockAllocationTable,
1153	pImage->cBlockAllocationTableEntries * sizeof(uint32_t));
1154	if (RT_FAILURE(rc))
1155	return vdIfError(pImage->pIfError, rc, RT_SRC_POS, N_("VHD: cannot write BAT to image '%s'"), pImage->pszFilename);
1156
1157	return rc;
1158	}
1159
1160	/**
1161	* Internal: The actual code for VHD image creation, both fixed and dynamic.
1162	*/
1163	static int vhdCreateImage(PVHDIMAGE pImage, uint64_t cbSize,
1164	unsigned uImageFlags, const char *pszComment,
1165	PCVDGEOMETRY pPCHSGeometry,
1166	PCVDGEOMETRY pLCHSGeometry, PCRTUUID pUuid,
1167	unsigned uOpenFlags,
1168	PVDINTERFACEPROGRESS pIfProgress,
1169	unsigned uPercentStart, unsigned uPercentSpan)
1170	{
1171	RT_NOREF3(pszComment, pPCHSGeometry, pLCHSGeometry);
1172	VHDFooter Footer;
1173	RTTIMESPEC now;
1174
1175	pImage->uOpenFlags = uOpenFlags;
1176	pImage->uImageFlags = uImageFlags;
1177	pImage->pIfError = VDIfErrorGet(pImage->pVDIfsDisk);
1178
1179	int rc = vdIfIoIntFileOpen(pImage->pIfIo, pImage->pszFilename,
1180	VDOpenFlagsToFileOpenFlags(uOpenFlags & ~VD_OPEN_FLAGS_READONLY,
1181	true /* fCreate */),
1182	&pImage->pStorage);
1183	if (RT_SUCCESS(rc))
1184	{
1185	pImage->cbSize = cbSize;
1186	pImage->ImageUuid = *pUuid;
1187	RTUuidClear(&pImage->ParentUuid);
1188	vhdSetDiskGeometry(pImage, cbSize);
1189
1190	/* Initialize the footer. */
1191	memset(&Footer, 0, sizeof(Footer));
1192	memcpy(Footer.Cookie, VHD_FOOTER_COOKIE, sizeof(Footer.Cookie));
1193	Footer.Features = RT_H2BE_U32(0x2);
1194	Footer.Version = RT_H2BE_U32(VHD_FOOTER_FILE_FORMAT_VERSION);
1195	Footer.Timestamp = RT_H2BE_U32(vhdRtTime2VhdTime(RTTimeNow(&now)));
1196	memcpy(Footer.CreatorApp, "vbox", sizeof(Footer.CreatorApp));
1197	Footer.CreatorVer = RT_H2BE_U32(VBOX_VERSION);
1198	#ifdef RT_OS_DARWIN
1199	Footer.CreatorOS = RT_H2BE_U32(0x4D616320); /* "Mac " */
1200	#else /* Virtual PC supports only two platforms atm, so everything else will be Wi2k. */
1201	Footer.CreatorOS = RT_H2BE_U32(0x5769326B); /* "Wi2k" */
1202	#endif
1203	Footer.OrigSize = RT_H2BE_U64(cbSize);
1204	Footer.CurSize = Footer.OrigSize;
1205	Footer.DiskGeometryCylinder = RT_H2BE_U16(pImage->PCHSGeometry.cCylinders);
1206	Footer.DiskGeometryHeads = pImage->PCHSGeometry.cHeads;
1207	Footer.DiskGeometrySectors = pImage->PCHSGeometry.cSectors;
1208	memcpy(Footer.UniqueID, pImage->ImageUuid.au8, sizeof(Footer.UniqueID));
1209	Footer.SavedState = 0;
1210
1211	if (uImageFlags & VD_IMAGE_FLAGS_FIXED)
1212	{
1213	Footer.DiskType = RT_H2BE_U32(VHD_FOOTER_DISK_TYPE_FIXED);
1214	/*
1215	* Initialize fixed image.
1216	* "The size of the entire file is the size of the hard disk in
1217	* the guest operating system plus the size of the footer."
1218	*/
1219	pImage->u64DataOffset = VHD_FOOTER_DATA_OFFSET_FIXED;
1220	pImage->uCurrentEndOfFile = cbSize;
1221	rc = vdIfIoIntFileSetAllocationSize(pImage->pIfIo, pImage->pStorage, pImage->uCurrentEndOfFile + sizeof(VHDFooter),
1222	0 /* fFlags */, pIfProgress,
1223	uPercentStart, uPercentSpan);
1224	if (RT_FAILURE(rc))
1225	rc = vdIfError(pImage->pIfError, rc, RT_SRC_POS, N_("VHD: cannot set the file size for '%s'"), pImage->pszFilename);
1226	}
1227	else
1228	{
1229	/*
1230	* Initialize dynamic image.
1231	*
1232	* The overall structure of dynamic disk is:
1233	*
1234	* [Copy of hard disk footer (512 bytes)]
1235	* [Dynamic disk header (1024 bytes)]
1236	* [BAT (Block Allocation Table)]
1237	* [Parent Locators]
1238	* [Data block 1]
1239	* [Data block 2]
1240	* ...
1241	* [Data block N]
1242	* [Hard disk footer (512 bytes)]
1243	*/
1244	Footer.DiskType = (uImageFlags & VD_IMAGE_FLAGS_DIFF)
1245	? RT_H2BE_U32(VHD_FOOTER_DISK_TYPE_DIFFERENCING)
1246	: RT_H2BE_U32(VHD_FOOTER_DISK_TYPE_DYNAMIC);
1247	/* We are half way thorough with creation of image, let the caller know. */
1248	vdIfProgress(pIfProgress, (uPercentStart + uPercentSpan) / 2);
1249
1250	rc = vhdCreateDynamicImage(pImage, cbSize);
1251	}
1252
1253	if (RT_SUCCESS(rc))
1254	{
1255	/* Compute and update the footer checksum. */
1256	Footer.DataOffset = RT_H2BE_U64(pImage->u64DataOffset);
1257	Footer.Checksum = 0;
1258	Footer.Checksum = RT_H2BE_U32(vhdChecksum(&Footer, sizeof(Footer)));
1259
1260	pImage->vhdFooterCopy = Footer;
1261
1262	/* Store the footer */
1263	rc = vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage, pImage->uCurrentEndOfFile,
1264	&Footer, sizeof(Footer));
1265	if (RT_SUCCESS(rc))
1266	{
1267	/* Dynamic images contain a copy of the footer at the very beginning of the file. */
1268	if (!(uImageFlags & VD_IMAGE_FLAGS_FIXED))
1269	{
1270	/* Write the copy of the footer. */
1271	rc = vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage, 0, &Footer, sizeof(Footer));
1272	if (RT_FAILURE(rc))
1273	rc = vdIfError(pImage->pIfError, rc, RT_SRC_POS, N_("VHD: cannot write a copy of footer to image '%s'"), pImage->pszFilename);
1274	}
1275	}
1276	else
1277	rc = vdIfError(pImage->pIfError, rc, RT_SRC_POS, N_("VHD: cannot write footer to image '%s'"), pImage->pszFilename);
1278	}
1279	}
1280	else
1281	rc = vdIfError(pImage->pIfError, rc, RT_SRC_POS, N_("VHD: cannot create image '%s'"), pImage->pszFilename);
1282
1283	if (RT_SUCCESS(rc))
1284	vdIfProgress(pIfProgress, uPercentStart + uPercentSpan);
1285
1286	if (RT_SUCCESS(rc))
1287	{
1288	PVDREGIONDESC pRegion = &pImage->RegionList.aRegions[0];
1289	pImage->RegionList.fFlags = 0;
1290	pImage->RegionList.cRegions = 1;
1291
1292	pRegion->offRegion = 0; /* Disk start. */
1293	pRegion->cbBlock = 512;
1294	pRegion->enmDataForm = VDREGIONDATAFORM_RAW;
1295	pRegion->enmMetadataForm = VDREGIONMETADATAFORM_NONE;
1296	pRegion->cbData = 512;
1297	pRegion->cbMetadata = 0;
1298	pRegion->cRegionBlocksOrBytes = pImage->cbSize;
1299	}
1300	else
1301	vhdFreeImage(pImage, rc != VERR_ALREADY_EXISTS);
1302	return rc;
1303	}
1304
1305
1306	/** @interface_method_impl{VDIMAGEBACKEND,pfnProbe} */
1307	static DECLCALLBACK(int) vhdProbe(const char *pszFilename, PVDINTERFACE pVDIfsDisk,
1308	PVDINTERFACE pVDIfsImage, VDTYPE enmDesiredType, VDTYPE *penmType)
1309	{
1310	RT_NOREF(pVDIfsDisk, enmDesiredType);
1311	LogFlowFunc(("pszFilename=\"%s\" pVDIfsDisk=%#p pVDIfsImage=%#p\n", pszFilename, pVDIfsDisk, pVDIfsImage));
1312	PVDIOSTORAGE pStorage;
1313	PVDINTERFACEIOINT pIfIo = VDIfIoIntGet(pVDIfsImage);
1314	AssertPtrReturn(pIfIo, VERR_INVALID_PARAMETER);
1315
1316	int rc = vdIfIoIntFileOpen(pIfIo, pszFilename,
1317	VDOpenFlagsToFileOpenFlags(VD_OPEN_FLAGS_READONLY,
1318	false /* fCreate */),
1319	&pStorage);
1320	if (RT_SUCCESS(rc))
1321	{
1322	uint64_t cbFile;
1323
1324	rc = vdIfIoIntFileGetSize(pIfIo, pStorage, &cbFile);
1325	if ( RT_SUCCESS(rc)
1326	&& cbFile >= sizeof(VHDFooter))
1327	{
1328	VHDFooter vhdFooter;
1329
1330	rc = vdIfIoIntFileReadSync(pIfIo, pStorage, cbFile - sizeof(VHDFooter),
1331	&vhdFooter, sizeof(VHDFooter));
1332	if (RT_SUCCESS(rc))
1333	{
1334	if (memcmp(vhdFooter.Cookie, VHD_FOOTER_COOKIE, VHD_FOOTER_COOKIE_SIZE) != 0)
1335	{
1336	/*
1337	* There is also a backup header at the beginning in case the image got corrupted.
1338	* Such corrupted images are detected here to let the open handler repair it later.
1339	*/
1340	rc = vdIfIoIntFileReadSync(pIfIo, pStorage, 0, &vhdFooter, sizeof(VHDFooter));
1341	if ( RT_FAILURE(rc)
1342	\|\| (memcmp(vhdFooter.Cookie, VHD_FOOTER_COOKIE, VHD_FOOTER_COOKIE_SIZE) != 0))
1343	rc = VERR_VD_VHD_INVALID_HEADER;
1344	}
1345
1346	if (RT_SUCCESS(rc))
1347	*penmType = VDTYPE_HDD;
1348	}
1349	else
1350	rc = VERR_VD_VHD_INVALID_HEADER;
1351	}
1352	else if (RT_SUCCESS(rc))
1353	rc = VERR_VD_VHD_INVALID_HEADER;
1354
1355	vdIfIoIntFileClose(pIfIo, pStorage);
1356	}
1357
1358	LogFlowFunc(("returns %Rrc\n", rc));
1359	return rc;
1360	}
1361
1362	/** @interface_method_impl{VDIMAGEBACKEND,pfnOpen} */
1363	static DECLCALLBACK(int) vhdOpen(const char *pszFilename, unsigned uOpenFlags,
1364	PVDINTERFACE pVDIfsDisk, PVDINTERFACE pVDIfsImage,
1365	VDTYPE enmType, void **ppBackendData)
1366	{
1367	RT_NOREF1(enmType); /*< @todo r=klaus make use of the type info. /
1368
1369	LogFlowFunc(("pszFilename=\"%s\" uOpenFlags=%#x pVDIfsDisk=%#p pVDIfsImage=%#p enmType=%u ppBackendData=%#p\n",
1370	pszFilename, uOpenFlags, pVDIfsDisk, pVDIfsImage, enmType, ppBackendData));
1371	int rc = VINF_SUCCESS;
1372
1373	/* Check open flags. All valid flags are supported. */
1374	AssertReturn(!(uOpenFlags & ~VD_OPEN_FLAGS_MASK), VERR_INVALID_PARAMETER);
1375	AssertPtrReturn(pszFilename, VERR_INVALID_POINTER);
1376	AssertReturn(*pszFilename != '\0', VERR_INVALID_PARAMETER);
1377
1378
1379	PVHDIMAGE pImage = (PVHDIMAGE)RTMemAllocZ(RT_UOFFSETOF(VHDIMAGE, RegionList.aRegions[1]));
1380	if (RT_LIKELY(pImage))
1381	{
1382	pImage->pszFilename = pszFilename;
1383	pImage->pStorage = NULL;
1384	pImage->pVDIfsDisk = pVDIfsDisk;
1385	pImage->pVDIfsImage = pVDIfsImage;
1386
1387	rc = vhdOpenImage(pImage, uOpenFlags);
1388	if (RT_SUCCESS(rc))
1389	*ppBackendData = pImage;
1390	else
1391	RTMemFree(pImage);
1392	}
1393	else
1394	rc = VERR_NO_MEMORY;
1395
1396	LogFlowFunc(("returns %Rrc (pBackendData=%#p)\n", rc, *ppBackendData));
1397	return rc;
1398	}
1399
1400	/** @interface_method_impl{VDIMAGEBACKEND,pfnCreate} */
1401	static DECLCALLBACK(int) vhdCreate(const char *pszFilename, uint64_t cbSize,
1402	unsigned uImageFlags, const char *pszComment,
1403	PCVDGEOMETRY pPCHSGeometry, PCVDGEOMETRY pLCHSGeometry,
1404	PCRTUUID pUuid, unsigned uOpenFlags,
1405	unsigned uPercentStart, unsigned uPercentSpan,
1406	PVDINTERFACE pVDIfsDisk, PVDINTERFACE pVDIfsImage,
1407	PVDINTERFACE pVDIfsOperation, VDTYPE enmType,
1408	void **ppBackendData)
1409	{
1410	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",
1411	pszFilename, cbSize, uImageFlags, pszComment, pPCHSGeometry, pLCHSGeometry, pUuid, uOpenFlags, uPercentStart, uPercentSpan, pVDIfsDisk, pVDIfsImage, pVDIfsOperation, enmType, ppBackendData));
1412	int rc;
1413	PVDINTERFACEPROGRESS pIfProgress = VDIfProgressGet(pVDIfsOperation);
1414
1415	/* Check the VD container type. */
1416	if (enmType != VDTYPE_HDD)
1417	return VERR_VD_INVALID_TYPE;
1418
1419	/* Check open flags. All valid flags are supported. */
1420	AssertReturn(!(uOpenFlags & ~VD_OPEN_FLAGS_MASK), VERR_INVALID_PARAMETER);
1421	AssertPtrReturn(pszFilename, VERR_INVALID_POINTER);
1422	AssertReturn(*pszFilename != '\0', VERR_INVALID_PARAMETER);
1423	AssertPtrReturn(pPCHSGeometry, VERR_INVALID_POINTER);
1424	AssertPtrReturn(pLCHSGeometry, VERR_INVALID_POINTER);
1425	/** @todo Check the values of other params */
1426
1427	PVHDIMAGE pImage = (PVHDIMAGE)RTMemAllocZ(RT_UOFFSETOF(VHDIMAGE, RegionList.aRegions[1]));
1428	if (RT_LIKELY(pImage))
1429	{
1430	pImage->pszFilename = pszFilename;
1431	pImage->pStorage = NULL;
1432	pImage->pVDIfsDisk = pVDIfsDisk;
1433	pImage->pVDIfsImage = pVDIfsImage;
1434
1435	/* Get I/O interface. */
1436	pImage->pIfIo = VDIfIoIntGet(pImage->pVDIfsImage);
1437	if (RT_LIKELY(RT_VALID_PTR(pImage->pIfIo)))
1438	{
1439	rc = vhdCreateImage(pImage, cbSize, uImageFlags, pszComment,
1440	pPCHSGeometry, pLCHSGeometry, pUuid, uOpenFlags,
1441	pIfProgress, uPercentStart, uPercentSpan);
1442	if (RT_SUCCESS(rc))
1443	{
1444	/* So far the image is opened in read/write mode. Make sure the
1445	* image is opened in read-only mode if the caller requested that. */
1446	if (uOpenFlags & VD_OPEN_FLAGS_READONLY)
1447	{
1448	vhdFreeImage(pImage, false);
1449	rc = vhdOpenImage(pImage, uOpenFlags);
1450	}
1451
1452	if (RT_SUCCESS(rc))
1453	*ppBackendData = pImage;
1454	}
1455	}
1456	else
1457	rc = VERR_INVALID_PARAMETER;
1458
1459	if (RT_FAILURE(rc))
1460	RTMemFree(pImage);
1461	}
1462	else
1463	rc = VERR_NO_MEMORY;
1464
1465	LogFlowFunc(("returns %Rrc\n", rc));
1466	return rc;
1467	}
1468
1469	/** @interface_method_impl{VDIMAGEBACKEND,pfnRename} */
1470	static DECLCALLBACK(int) vhdRename(void pBackendData, const char pszFilename)
1471	{
1472	LogFlowFunc(("pBackendData=%#p pszFilename=%#p\n", pBackendData, pszFilename));
1473	int rc = VINF_SUCCESS;
1474	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
1475
1476	/* Check arguments. */
1477	AssertReturn((pImage && pszFilename && *pszFilename), VERR_INVALID_PARAMETER);
1478
1479	/* Close the image. */
1480	rc = vhdFreeImage(pImage, false);
1481	if (RT_SUCCESS(rc))
1482	{
1483	/* Rename the file. */
1484	rc = vdIfIoIntFileMove(pImage->pIfIo, pImage->pszFilename, pszFilename, 0);
1485	if (RT_SUCCESS(rc))
1486	{
1487	/* Update pImage with the new information. */
1488	pImage->pszFilename = pszFilename;
1489
1490	/* Open the old file with new name. */
1491	rc = vhdOpenImage(pImage, pImage->uOpenFlags);
1492	}
1493	else
1494	{
1495	/* The move failed, try to reopen the original image. */
1496	int rc2 = vhdOpenImage(pImage, pImage->uOpenFlags);
1497	if (RT_FAILURE(rc2))
1498	rc = rc2;
1499	}
1500	}
1501
1502	LogFlowFunc(("returns %Rrc\n", rc));
1503	return rc;
1504	}
1505
1506	/** @interface_method_impl{VDIMAGEBACKEND,pfnClose} */
1507	static DECLCALLBACK(int) vhdClose(void *pBackendData, bool fDelete)
1508	{
1509	LogFlowFunc(("pBackendData=%#p fDelete=%d\n", pBackendData, fDelete));
1510	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
1511
1512	int rc = vhdFreeImage(pImage, fDelete);
1513	RTMemFree(pImage);
1514
1515	LogFlowFunc(("returns %Rrc\n", rc));
1516	return rc;
1517	}
1518
1519	/** @interface_method_impl{VDIMAGEBACKEND,pfnRead} */
1520	static DECLCALLBACK(int) vhdRead(void *pBackendData, uint64_t uOffset, size_t cbToRead,
1521	PVDIOCTX pIoCtx, size_t *pcbActuallyRead)
1522	{
1523	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
1524	int rc = VINF_SUCCESS;
1525
1526	LogFlowFunc(("pBackendData=%p uOffset=%#llx pIoCtx=%#p cbToRead=%u pcbActuallyRead=%p\n",
1527	pBackendData, uOffset, pIoCtx, cbToRead, pcbActuallyRead));
1528
1529	AssertPtr(pImage);
1530	Assert(uOffset % 512 == 0);
1531	Assert(cbToRead % 512 == 0);
1532	AssertPtrReturn(pIoCtx, VERR_INVALID_POINTER);
1533	AssertReturn(cbToRead, VERR_INVALID_PARAMETER);
1534	AssertReturn(uOffset + cbToRead <= pImage->cbSize, VERR_INVALID_PARAMETER);
1535
1536	/*
1537	* If we have a dynamic disk image, we need to find the data block and sector to read.
1538	*/
1539	if (pImage->pBlockAllocationTable)
1540	{
1541	/*
1542	* Get the data block first.
1543	*/
1544	uint32_t cBlockAllocationTableEntry = (uOffset / VHD_SECTOR_SIZE) / pImage->cSectorsPerDataBlock;
1545	uint32_t cBATEntryIndex = (uOffset / VHD_SECTOR_SIZE) % pImage->cSectorsPerDataBlock;
1546	uint64_t uVhdOffset;
1547
1548	LogFlowFunc(("cBlockAllocationTableEntry=%u cBatEntryIndex=%u\n", cBlockAllocationTableEntry, cBATEntryIndex));
1549	LogFlowFunc(("BlockAllocationEntry=%u\n", pImage->pBlockAllocationTable[cBlockAllocationTableEntry]));
1550
1551	/*
1552	* Clip read range to remain in this data block.
1553	*/
1554	cbToRead = RT_MIN(cbToRead, (pImage->cbDataBlock - (cBATEntryIndex * VHD_SECTOR_SIZE)));
1555
1556	/*
1557	* If the block is not allocated the content of the entry is ~0
1558	*/
1559	if (pImage->pBlockAllocationTable[cBlockAllocationTableEntry] == ~0U)
1560	rc = VERR_VD_BLOCK_FREE;
1561	else
1562	{
1563	uVhdOffset = ((uint64_t)pImage->pBlockAllocationTable[cBlockAllocationTableEntry] + pImage->cDataBlockBitmapSectors + cBATEntryIndex) * VHD_SECTOR_SIZE;
1564	LogFlowFunc(("uVhdOffset=%llu cbToRead=%u\n", uVhdOffset, cbToRead));
1565
1566	/* Read in the block's bitmap. */
1567	PVDMETAXFER pMetaXfer;
1568	rc = vdIfIoIntFileReadMeta(pImage->pIfIo, pImage->pStorage,
1569	((uint64_t)pImage->pBlockAllocationTable[cBlockAllocationTableEntry]) * VHD_SECTOR_SIZE,
1570	pImage->pu8Bitmap, pImage->cbDataBlockBitmap,
1571	pIoCtx, &pMetaXfer, NULL, NULL);
1572
1573	if (RT_SUCCESS(rc))
1574	{
1575	uint32_t cSectors = 0;
1576
1577	vdIfIoIntMetaXferRelease(pImage->pIfIo, pMetaXfer);
1578	if (vhdBlockBitmapSectorContainsData(pImage, cBATEntryIndex))
1579	{
1580	cBATEntryIndex++;
1581	cSectors = 1;
1582
1583	/*
1584	* The first sector being read is marked dirty, read as much as we
1585	* can from child. Note that only sectors that are marked dirty
1586	* must be read from child.
1587	*/
1588	while ( (cSectors < (cbToRead / VHD_SECTOR_SIZE))
1589	&& vhdBlockBitmapSectorContainsData(pImage, cBATEntryIndex))
1590	{
1591	cBATEntryIndex++;
1592	cSectors++;
1593	}
1594
1595	cbToRead = cSectors * VHD_SECTOR_SIZE;
1596
1597	LogFlowFunc(("uVhdOffset=%llu cbToRead=%u\n", uVhdOffset, cbToRead));
1598	rc = vdIfIoIntFileReadUser(pImage->pIfIo, pImage->pStorage,
1599	uVhdOffset, pIoCtx, cbToRead);
1600	}
1601	else
1602	{
1603	/*
1604	* The first sector being read is marked clean, so we should read from
1605	* our parent instead, but only as much as there are the following
1606	* clean sectors, because the block may still contain dirty sectors
1607	* further on. We just need to compute the number of clean sectors
1608	* and pass it to our caller along with the notification that they
1609	* should be read from the parent.
1610	*/
1611	cBATEntryIndex++;
1612	cSectors = 1;
1613
1614	while ( (cSectors < (cbToRead / VHD_SECTOR_SIZE))
1615	&& !vhdBlockBitmapSectorContainsData(pImage, cBATEntryIndex))
1616	{
1617	cBATEntryIndex++;
1618	cSectors++;
1619	}
1620
1621	cbToRead = cSectors * VHD_SECTOR_SIZE;
1622	LogFunc(("Sectors free: uVhdOffset=%llu cbToRead=%u\n", uVhdOffset, cbToRead));
1623	rc = VERR_VD_BLOCK_FREE;
1624	}
1625	}
1626	else
1627	AssertMsg(rc == VERR_VD_NOT_ENOUGH_METADATA, ("Reading block bitmap failed rc=%Rrc\n", rc));
1628	}
1629	}
1630	else
1631	rc = vdIfIoIntFileReadUser(pImage->pIfIo, pImage->pStorage, uOffset, pIoCtx, cbToRead);
1632
1633	if (pcbActuallyRead)
1634	*pcbActuallyRead = cbToRead;
1635
1636	LogFlowFunc(("returns rc=%Rrc\n", rc));
1637	return rc;
1638	}
1639
1640	/** @interface_method_impl{VDIMAGEBACKEND,pfnWrite} */
1641	static DECLCALLBACK(int) vhdWrite(void *pBackendData, uint64_t uOffset, size_t cbToWrite,
1642	PVDIOCTX pIoCtx, size_t pcbWriteProcess, size_t pcbPreRead,
1643	size_t *pcbPostRead, unsigned fWrite)
1644	{
1645	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
1646	int rc = VINF_SUCCESS;
1647
1648	LogFlowFunc(("pBackendData=%p uOffset=%llu pIoCtx=%#p cbToWrite=%u pcbWriteProcess=%p pcbPreRead=%p pcbPostRead=%p fWrite=%u\n",
1649	pBackendData, uOffset, pIoCtx, cbToWrite, pcbWriteProcess, pcbPreRead, pcbPostRead, fWrite));
1650
1651	AssertPtr(pImage);
1652	Assert(!(uOffset % VHD_SECTOR_SIZE));
1653	Assert(!(cbToWrite % VHD_SECTOR_SIZE));
1654	AssertPtrReturn(pIoCtx, VERR_INVALID_POINTER);
1655	AssertReturn(cbToWrite, VERR_INVALID_PARAMETER);
1656	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. */
1657
1658	if (pImage->pBlockAllocationTable)
1659	{
1660	/*
1661	* Get the data block first.
1662	*/
1663	uint32_t cSector = uOffset / VHD_SECTOR_SIZE;
1664	uint32_t cBlockAllocationTableEntry = cSector / pImage->cSectorsPerDataBlock;
1665	uint32_t cBATEntryIndex = cSector % pImage->cSectorsPerDataBlock;
1666	uint64_t uVhdOffset;
1667
1668	/*
1669	* Clip write range.
1670	*/
1671	cbToWrite = RT_MIN(cbToWrite, (pImage->cbDataBlock - (cBATEntryIndex * VHD_SECTOR_SIZE)));
1672
1673	/*
1674	* If the block is not allocated the content of the entry is ~0
1675	* and we need to allocate a new block. Note that while blocks are
1676	* allocated with a relatively big granularity, each sector has its
1677	* own bitmap entry, indicating whether it has been written or not.
1678	* So that means for the purposes of the higher level that the
1679	* granularity is invisible. This means there's no need to return
1680	* VERR_VD_BLOCK_FREE unless the block hasn't been allocated yet.
1681	*/
1682	if (pImage->pBlockAllocationTable[cBlockAllocationTableEntry] == ~0U)
1683	{
1684	/* Check if the block allocation should be suppressed. */
1685	if ( (fWrite & VD_WRITE_NO_ALLOC)
1686	\|\| (cbToWrite != pImage->cbDataBlock))
1687	{
1688	pcbPreRead = cBATEntryIndex VHD_SECTOR_SIZE;
1689	pcbPostRead = pImage->cSectorsPerDataBlock VHD_SECTOR_SIZE - cbToWrite - *pcbPreRead;
1690
1691	if (pcbWriteProcess)
1692	*pcbWriteProcess = cbToWrite;
1693	return VERR_VD_BLOCK_FREE;
1694	}
1695
1696	PVHDIMAGEEXPAND pExpand;
1697	pExpand = (PVHDIMAGEEXPAND)RTMemAllocZ(RT_UOFFSETOF_DYN(VHDIMAGEEXPAND,
1698	au8Bitmap[pImage->cDataBlockBitmapSectors * VHD_SECTOR_SIZE]));
1699	bool fIoInProgress = false;
1700
1701	if (!pExpand)
1702	return VERR_NO_MEMORY;
1703
1704	pExpand->cbEofOld = pImage->uCurrentEndOfFile;
1705	pExpand->idxBatAllocated = cBlockAllocationTableEntry;
1706	pExpand->idxBlockBe = RT_H2BE_U32(pImage->uCurrentEndOfFile / VHD_SECTOR_SIZE);
1707
1708	/* Set the bits for all sectors having been written. */
1709	for (uint32_t iSector = 0; iSector < (cbToWrite / VHD_SECTOR_SIZE); iSector++)
1710	{
1711	/* No need to check for a changed value because this is an initial write. */
1712	vhdBlockBitmapSectorSet(pImage, pExpand->au8Bitmap, cBATEntryIndex);
1713	cBATEntryIndex++;
1714	}
1715
1716	do
1717	{
1718	/*
1719	* Start with the sector bitmap.
1720	*/
1721	rc = vdIfIoIntFileWriteMeta(pImage->pIfIo, pImage->pStorage,
1722	pImage->uCurrentEndOfFile,
1723	pExpand->au8Bitmap,
1724	pImage->cDataBlockBitmapSectors * VHD_SECTOR_SIZE, pIoCtx,
1725	vhdAsyncExpansionDataBlockBitmapComplete,
1726	pExpand);
1727	if (RT_SUCCESS(rc))
1728	VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_BLOCKBITMAP_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_SUCCESS);
1729	else if (rc == VERR_VD_ASYNC_IO_IN_PROGRESS)
1730	fIoInProgress = true;
1731	else
1732	{
1733	VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_BLOCKBITMAP_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_FAILED);
1734	VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_USERBLOCK_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_FAILED);
1735	VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_BAT_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_FAILED);
1736	VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_FOOTER_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_FAILED);
1737	break;
1738	}
1739
1740
1741	/*
1742	* Write the new block at the current end of the file.
1743	*/
1744	rc = vdIfIoIntFileWriteUser(pImage->pIfIo, pImage->pStorage,
1745	pImage->uCurrentEndOfFile + (pImage->cDataBlockBitmapSectors + (cSector % pImage->cSectorsPerDataBlock)) * VHD_SECTOR_SIZE,
1746	pIoCtx, cbToWrite,
1747	vhdAsyncExpansionDataComplete,
1748	pExpand);
1749	if (RT_SUCCESS(rc))
1750	VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_USERBLOCK_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_SUCCESS);
1751	else if (rc == VERR_VD_ASYNC_IO_IN_PROGRESS)
1752	fIoInProgress = true;
1753	else
1754	{
1755	VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_USERBLOCK_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_FAILED);
1756	VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_BAT_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_FAILED);
1757	VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_FOOTER_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_FAILED);
1758	break;
1759	}
1760
1761	/*
1762	* Write entry in the BAT.
1763	*/
1764	rc = vdIfIoIntFileWriteMeta(pImage->pIfIo, pImage->pStorage,
1765	pImage->uBlockAllocationTableOffset + cBlockAllocationTableEntry * sizeof(uint32_t),
1766	&pExpand->idxBlockBe, sizeof(uint32_t), pIoCtx,
1767	vhdAsyncExpansionBatUpdateComplete,
1768	pExpand);
1769	if (RT_SUCCESS(rc))
1770	VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_BAT_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_SUCCESS);
1771	else if (rc == VERR_VD_ASYNC_IO_IN_PROGRESS)
1772	fIoInProgress = true;
1773	else
1774	{
1775	VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_BAT_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_FAILED);
1776	VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_FOOTER_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_FAILED);
1777	break;
1778	}
1779
1780	/*
1781	* Set the new end of the file and link the new block into the BAT.
1782	*/
1783	pImage->uCurrentEndOfFile += pImage->cDataBlockBitmapSectors * VHD_SECTOR_SIZE + pImage->cbDataBlock;
1784
1785	/* Update the footer. */
1786	rc = vdIfIoIntFileWriteMeta(pImage->pIfIo, pImage->pStorage,
1787	pImage->uCurrentEndOfFile,
1788	&pImage->vhdFooterCopy,
1789	sizeof(VHDFooter), pIoCtx,
1790	vhdAsyncExpansionFooterUpdateComplete,
1791	pExpand);
1792	if (RT_SUCCESS(rc))
1793	VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_FOOTER_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_SUCCESS);
1794	else if (rc == VERR_VD_ASYNC_IO_IN_PROGRESS)
1795	fIoInProgress = true;
1796	else
1797	{
1798	VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_FOOTER_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_FAILED);
1799	break;
1800	}
1801
1802	} while (0);
1803
1804	if (!fIoInProgress)
1805	vhdAsyncExpansionComplete(pImage, pIoCtx, pExpand);
1806	else
1807	rc = VERR_VD_ASYNC_IO_IN_PROGRESS;
1808	}
1809	else
1810	{
1811	/*
1812	* Calculate the real offset in the file.
1813	*/
1814	uVhdOffset = ((uint64_t)pImage->pBlockAllocationTable[cBlockAllocationTableEntry] + pImage->cDataBlockBitmapSectors + cBATEntryIndex) * VHD_SECTOR_SIZE;
1815
1816	/* Read in the block's bitmap. */
1817	PVDMETAXFER pMetaXfer;
1818	rc = vdIfIoIntFileReadMeta(pImage->pIfIo, pImage->pStorage,
1819	((uint64_t)pImage->pBlockAllocationTable[cBlockAllocationTableEntry]) * VHD_SECTOR_SIZE,
1820	pImage->pu8Bitmap,
1821	pImage->cbDataBlockBitmap, pIoCtx,
1822	&pMetaXfer, NULL, NULL);
1823	if (RT_SUCCESS(rc))
1824	{
1825	vdIfIoIntMetaXferRelease(pImage->pIfIo, pMetaXfer);
1826
1827	/* Write data. */
1828	rc = vdIfIoIntFileWriteUser(pImage->pIfIo, pImage->pStorage,
1829	uVhdOffset, pIoCtx, cbToWrite,
1830	NULL, NULL);
1831	if (RT_SUCCESS(rc) \|\| rc == VERR_VD_ASYNC_IO_IN_PROGRESS)
1832	{
1833	bool fChanged = false;
1834
1835	/* Set the bits for all sectors having been written. */
1836	for (uint32_t iSector = 0; iSector < (cbToWrite / VHD_SECTOR_SIZE); iSector++)
1837	{
1838	fChanged \|= vhdBlockBitmapSectorSet(pImage, pImage->pu8Bitmap, cBATEntryIndex);
1839	cBATEntryIndex++;
1840	}
1841
1842	/* Only write the bitmap if it was changed. */
1843	if (fChanged)
1844	{
1845	/*
1846	* Write the bitmap back.
1847	*
1848	* @note We don't have a completion callback here because we
1849	* can't do anything if the write fails for some reason.
1850	* The error will propagated to the device/guest
1851	* by the generic VD layer already and we don't need
1852	* to rollback anything here.
1853	*/
1854	rc = vdIfIoIntFileWriteMeta(pImage->pIfIo, pImage->pStorage,
1855	((uint64_t)pImage->pBlockAllocationTable[cBlockAllocationTableEntry]) * VHD_SECTOR_SIZE,
1856	pImage->pu8Bitmap,
1857	pImage->cbDataBlockBitmap,
1858	pIoCtx, NULL, NULL);
1859	}
1860	}
1861	}
1862	}
1863	}
1864	else
1865	rc = vdIfIoIntFileWriteUser(pImage->pIfIo, pImage->pStorage,
1866	uOffset, pIoCtx, cbToWrite, NULL, NULL);
1867
1868	if (pcbWriteProcess)
1869	*pcbWriteProcess = cbToWrite;
1870
1871	/* Stay on the safe side. Do not run the risk of confusing the higher
1872	* level, as that can be pretty lethal to image consistency. */
1873	*pcbPreRead = 0;
1874	*pcbPostRead = 0;
1875
1876	return rc;
1877	}
1878
1879	/** @interface_method_impl{VDIMAGEBACKEND,pfnFlush} */
1880	static DECLCALLBACK(int) vhdFlush(void *pBackendData, PVDIOCTX pIoCtx)
1881	{
1882	LogFlowFunc(("pBackendData=%#p\n", pBackendData));
1883	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
1884
1885	/* No need to write anything here. Data is always updated on a write. */
1886	int rc = vdIfIoIntFileFlush(pImage->pIfIo, pImage->pStorage, pIoCtx, NULL, NULL);
1887	LogFlowFunc(("returns %Rrc\n", rc));
1888	return rc;
1889	}
1890
1891	/** @interface_method_impl{VDIMAGEBACKEND,pfnGetVersion} */
1892	static DECLCALLBACK(unsigned) vhdGetVersion(void *pBackendData)
1893	{
1894	LogFlowFunc(("pBackendData=%#p\n", pBackendData));
1895	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
1896
1897	AssertPtrReturn(pImage, 0);
1898
1899	unsigned uVersion = 1; /*< @todo use correct version /
1900
1901	LogFlowFunc(("returns %u\n", uVersion));
1902	return uVersion;
1903	}
1904
1905	/** @interface_method_impl{VDIMAGEBACKEND,pfnGetFileSize} */
1906	static DECLCALLBACK(uint64_t) vhdGetFileSize(void *pBackendData)
1907	{
1908	LogFlowFunc(("pBackendData=%#p\n", pBackendData));
1909	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
1910	uint64_t cb = 0;
1911
1912	AssertPtrReturn(pImage, 0);
1913
1914	if (pImage->pStorage)
1915	cb = pImage->uCurrentEndOfFile + sizeof(VHDFooter);
1916
1917	LogFlowFunc(("returns %lld\n", cb));
1918	return cb;
1919	}
1920
1921	/** @interface_method_impl{VDIMAGEBACKEND,pfnGetPCHSGeometry} */
1922	static DECLCALLBACK(int) vhdGetPCHSGeometry(void *pBackendData, PVDGEOMETRY pPCHSGeometry)
1923	{
1924	LogFlowFunc(("pBackendData=%#p pPCHSGeometry=%#p\n", pBackendData, pPCHSGeometry));
1925	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
1926	int rc = VINF_SUCCESS;
1927
1928	AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
1929
1930	if (pImage->PCHSGeometry.cCylinders)
1931	*pPCHSGeometry = pImage->PCHSGeometry;
1932	else
1933	rc = VERR_VD_GEOMETRY_NOT_SET;
1934
1935	LogFlowFunc(("returns %Rrc (CHS=%u/%u/%u)\n", rc, pImage->PCHSGeometry.cCylinders,
1936	pImage->PCHSGeometry.cHeads, pImage->PCHSGeometry.cSectors));
1937	return rc;
1938	}
1939
1940	/** @interface_method_impl{VDIMAGEBACKEND,pfnSetPCHSGeometry} */
1941	static DECLCALLBACK(int) vhdSetPCHSGeometry(void *pBackendData, PCVDGEOMETRY pPCHSGeometry)
1942	{
1943	LogFlowFunc(("pBackendData=%#p pPCHSGeometry=%#p PCHS=%u/%u/%u\n",
1944	pBackendData, pPCHSGeometry, pPCHSGeometry->cCylinders, pPCHSGeometry->cHeads, pPCHSGeometry->cSectors));
1945	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
1946	int rc = VINF_SUCCESS;
1947
1948	AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
1949
1950	if (pImage->uOpenFlags & VD_OPEN_FLAGS_READONLY)
1951	rc = VERR_VD_IMAGE_READ_ONLY;
1952	else
1953	pImage->PCHSGeometry = *pPCHSGeometry;
1954
1955	LogFlowFunc(("returns %Rrc\n", rc));
1956	return rc;
1957	}
1958
1959	/** @interface_method_impl{VDIMAGEBACKEND,pfnGetLCHSGeometry} */
1960	static DECLCALLBACK(int) vhdGetLCHSGeometry(void *pBackendData, PVDGEOMETRY pLCHSGeometry)
1961	{
1962	LogFlowFunc(("pBackendData=%#p pLCHSGeometry=%#p\n", pBackendData, pLCHSGeometry));
1963	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
1964	int rc = VINF_SUCCESS;
1965
1966	AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
1967
1968	if (pImage->LCHSGeometry.cCylinders)
1969	*pLCHSGeometry = pImage->LCHSGeometry;
1970	else
1971	rc = VERR_VD_GEOMETRY_NOT_SET;
1972
1973	LogFlowFunc(("returns %Rrc (CHS=%u/%u/%u)\n", rc, pImage->LCHSGeometry.cCylinders,
1974	pImage->LCHSGeometry.cHeads, pImage->LCHSGeometry.cSectors));
1975	return rc;
1976	}
1977
1978	/** @interface_method_impl{VDIMAGEBACKEND,pfnSetLCHSGeometry} */
1979	static DECLCALLBACK(int) vhdSetLCHSGeometry(void *pBackendData, PCVDGEOMETRY pLCHSGeometry)
1980	{
1981	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
1982	int rc = VINF_SUCCESS;
1983
1984	AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
1985
1986	if (pImage->uOpenFlags & VD_OPEN_FLAGS_READONLY)
1987	rc = VERR_VD_IMAGE_READ_ONLY;
1988	else
1989	pImage->LCHSGeometry = *pLCHSGeometry;
1990
1991	LogFlowFunc(("returns %Rrc\n", rc));
1992	return rc;
1993	}
1994
1995	/** @copydoc VDIMAGEBACKEND::pfnQueryRegions */
1996	static DECLCALLBACK(int) vhdQueryRegions(void pBackendData, PCVDREGIONLIST ppRegionList)
1997	{
1998	LogFlowFunc(("pBackendData=%#p ppRegionList=%#p\n", pBackendData, ppRegionList));
1999	PVHDIMAGE pThis = (PVHDIMAGE)pBackendData;
2000
2001	AssertPtrReturn(pThis, VERR_VD_NOT_OPENED);
2002
2003	*ppRegionList = &pThis->RegionList;
2004	LogFlowFunc(("returns %Rrc\n", VINF_SUCCESS));
2005	return VINF_SUCCESS;
2006	}
2007
2008	/** @copydoc VDIMAGEBACKEND::pfnRegionListRelease */
2009	static DECLCALLBACK(void) vhdRegionListRelease(void *pBackendData, PCVDREGIONLIST pRegionList)
2010	{
2011	RT_NOREF1(pRegionList);
2012	LogFlowFunc(("pBackendData=%#p pRegionList=%#p\n", pBackendData, pRegionList));
2013	PVHDIMAGE pThis = (PVHDIMAGE)pBackendData;
2014	AssertPtr(pThis); RT_NOREF(pThis);
2015
2016	/* Nothing to do here. */
2017	}
2018
2019	/** @interface_method_impl{VDIMAGEBACKEND,pfnGetImageFlags} */
2020	static DECLCALLBACK(unsigned) vhdGetImageFlags(void *pBackendData)
2021	{
2022	LogFlowFunc(("pBackendData=%#p\n", pBackendData));
2023	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2024
2025	AssertPtrReturn(pImage, 0);
2026
2027	LogFlowFunc(("returns %#x\n", pImage->uImageFlags));
2028	return pImage->uImageFlags;
2029	}
2030
2031	/** @interface_method_impl{VDIMAGEBACKEND,pfnGetOpenFlags} */
2032	static DECLCALLBACK(unsigned) vhdGetOpenFlags(void *pBackendData)
2033	{
2034	LogFlowFunc(("pBackendData=%#p\n", pBackendData));
2035	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2036
2037	AssertPtrReturn(pImage, 0);
2038
2039	LogFlowFunc(("returns %#x\n", pImage->uOpenFlags));
2040	return pImage->uOpenFlags;
2041	}
2042
2043	/** @interface_method_impl{VDIMAGEBACKEND,pfnSetOpenFlags} */
2044	static DECLCALLBACK(int) vhdSetOpenFlags(void *pBackendData, unsigned uOpenFlags)
2045	{
2046	LogFlowFunc(("pBackendData=%#p\n uOpenFlags=%#x", pBackendData, uOpenFlags));
2047	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2048	int rc = VINF_SUCCESS;
2049
2050	/* Image must be opened and the new flags must be valid. */
2051	if (!pImage \|\| (uOpenFlags & ~( VD_OPEN_FLAGS_READONLY \| VD_OPEN_FLAGS_INFO
2052	\| VD_OPEN_FLAGS_ASYNC_IO \| VD_OPEN_FLAGS_SHAREABLE
2053	\| VD_OPEN_FLAGS_SEQUENTIAL \| VD_OPEN_FLAGS_SKIP_CONSISTENCY_CHECKS)))
2054	rc = VERR_INVALID_PARAMETER;
2055	else
2056	{
2057	/* Implement this operation via reopening the image. */
2058	rc = vhdFreeImage(pImage, false);
2059	if (RT_SUCCESS(rc))
2060	rc = vhdOpenImage(pImage, uOpenFlags);
2061	}
2062
2063	LogFlowFunc(("returns %Rrc\n", rc));
2064	return rc;
2065	}
2066
2067	/** @interface_method_impl{VDIMAGEBACKEND,pfnGetComment} */
2068	static DECLCALLBACK(int) vhdGetComment(void pBackendData, char pszComment,
2069	size_t cbComment)
2070	{
2071	RT_NOREF2(pszComment, cbComment);
2072	LogFlowFunc(("pBackendData=%#p pszComment=%#p cbComment=%zu\n", pBackendData, pszComment, cbComment));
2073	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2074
2075	AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
2076
2077	LogFlowFunc(("returns %Rrc comment='%s'\n", VERR_NOT_SUPPORTED, pszComment));
2078	return VERR_NOT_SUPPORTED;
2079	}
2080
2081	/** @interface_method_impl{VDIMAGEBACKEND,pfnSetComment} */
2082	static DECLCALLBACK(int) vhdSetComment(void pBackendData, const char pszComment)
2083	{
2084	RT_NOREF1(pszComment);
2085	LogFlowFunc(("pBackendData=%#p pszComment=\"%s\"\n", pBackendData, pszComment));
2086	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2087
2088	AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
2089
2090	int rc;
2091	if (pImage->uOpenFlags & VD_OPEN_FLAGS_READONLY)
2092	rc = VERR_VD_IMAGE_READ_ONLY;
2093	else
2094	rc = VERR_NOT_SUPPORTED;
2095
2096	LogFlowFunc(("returns %Rrc\n", rc));
2097	return rc;
2098	}
2099
2100	/** @interface_method_impl{VDIMAGEBACKEND,pfnGetUuid} */
2101	static DECLCALLBACK(int) vhdGetUuid(void *pBackendData, PRTUUID pUuid)
2102	{
2103	LogFlowFunc(("pBackendData=%#p pUuid=%#p\n", pBackendData, pUuid));
2104	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2105
2106	AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
2107
2108	*pUuid = pImage->ImageUuid;
2109
2110	LogFlowFunc(("returns %Rrc (%RTuuid)\n", VINF_SUCCESS, pUuid));
2111	return VINF_SUCCESS;
2112	}
2113
2114	/** @interface_method_impl{VDIMAGEBACKEND,pfnSetUuid} */
2115	static DECLCALLBACK(int) vhdSetUuid(void *pBackendData, PCRTUUID pUuid)
2116	{
2117	LogFlowFunc(("pBackendData=%#p Uuid=%RTuuid\n", pBackendData, pUuid));
2118	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2119	int rc = VINF_SUCCESS;
2120
2121	AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
2122
2123	if (!(pImage->uOpenFlags & VD_OPEN_FLAGS_READONLY))
2124	{
2125	pImage->ImageUuid = *pUuid;
2126	/* Update the footer copy. It will get written to disk when the image is closed. */
2127	memcpy(&pImage->vhdFooterCopy.UniqueID, pUuid, 16);
2128	/* Update checksum. */
2129	pImage->vhdFooterCopy.Checksum = 0;
2130	pImage->vhdFooterCopy.Checksum = RT_H2BE_U32(vhdChecksum(&pImage->vhdFooterCopy, sizeof(VHDFooter)));
2131
2132	/* Need to update the dynamic disk header to update the disk footer copy at the beginning. */
2133	if (!(pImage->uImageFlags & VD_IMAGE_FLAGS_FIXED))
2134	pImage->fDynHdrNeedsUpdate = true;
2135	}
2136	else
2137	rc = VERR_VD_IMAGE_READ_ONLY;
2138
2139	LogFlowFunc(("returns %Rrc\n", rc));
2140	return rc;
2141	}
2142
2143	/** @interface_method_impl{VDIMAGEBACKEND,pfnGetModificationUuid} */
2144	static DECLCALLBACK(int) vhdGetModificationUuid(void *pBackendData, PRTUUID pUuid)
2145	{
2146	RT_NOREF1(pUuid);
2147	LogFlowFunc(("pBackendData=%#p pUuid=%#p\n", pBackendData, pUuid));
2148	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2149
2150	AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
2151
2152	LogFlowFunc(("returns %Rrc (%RTuuid)\n", VERR_NOT_SUPPORTED, pUuid));
2153	return VERR_NOT_SUPPORTED;
2154	}
2155
2156	/** @interface_method_impl{VDIMAGEBACKEND,pfnSetModificationUuid} */
2157	static DECLCALLBACK(int) vhdSetModificationUuid(void *pBackendData, PCRTUUID pUuid)
2158	{
2159	RT_NOREF1(pUuid);
2160	LogFlowFunc(("pBackendData=%#p Uuid=%RTuuid\n", pBackendData, pUuid));
2161	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2162
2163	AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
2164
2165	int rc;
2166	if (pImage->uOpenFlags & VD_OPEN_FLAGS_READONLY)
2167	rc = VERR_VD_IMAGE_READ_ONLY;
2168	else
2169	rc = VERR_NOT_SUPPORTED;
2170
2171	LogFlowFunc(("returns %Rrc\n", rc));
2172	return rc;
2173	}
2174
2175	/** @interface_method_impl{VDIMAGEBACKEND,pfnGetParentUuid} */
2176	static DECLCALLBACK(int) vhdGetParentUuid(void *pBackendData, PRTUUID pUuid)
2177	{
2178	LogFlowFunc(("pBackendData=%#p pUuid=%#p\n", pBackendData, pUuid));
2179	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2180
2181	AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
2182
2183	*pUuid = pImage->ParentUuid;
2184
2185	LogFlowFunc(("returns %Rrc (%RTuuid)\n", VINF_SUCCESS, pUuid));
2186	return VINF_SUCCESS;
2187	}
2188
2189	/** @interface_method_impl{VDIMAGEBACKEND,pfnSetParentUuid} */
2190	static DECLCALLBACK(int) vhdSetParentUuid(void *pBackendData, PCRTUUID pUuid)
2191	{
2192	LogFlowFunc(("pBackendData=%#p Uuid=%RTuuid\n", pBackendData, pUuid));
2193	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2194	int rc = VINF_SUCCESS;
2195
2196	if (pImage && pImage->pStorage)
2197	{
2198	if (!(pImage->uImageFlags & VD_IMAGE_FLAGS_FIXED))
2199	{
2200	pImage->ParentUuid = *pUuid;
2201	pImage->fDynHdrNeedsUpdate = true;
2202	}
2203	else
2204	rc = VERR_VD_IMAGE_READ_ONLY;
2205	}
2206	else
2207	rc = VERR_VD_NOT_OPENED;
2208
2209	LogFlowFunc(("returns %Rrc\n", rc));
2210	return rc;
2211	}
2212
2213	/** @interface_method_impl{VDIMAGEBACKEND,pfnGetParentModificationUuid} */
2214	static DECLCALLBACK(int) vhdGetParentModificationUuid(void *pBackendData, PRTUUID pUuid)
2215	{
2216	RT_NOREF1(pUuid);
2217	LogFlowFunc(("pBackendData=%#p pUuid=%#p\n", pBackendData, pUuid));
2218	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2219
2220	AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
2221
2222	LogFlowFunc(("returns %Rrc (%RTuuid)\n", VERR_NOT_SUPPORTED, pUuid));
2223	return VERR_NOT_SUPPORTED;
2224	}
2225
2226	/** @interface_method_impl{VDIMAGEBACKEND,pfnSetParentModificationUuid} */
2227	static DECLCALLBACK(int) vhdSetParentModificationUuid(void *pBackendData, PCRTUUID pUuid)
2228	{
2229	RT_NOREF1(pUuid);
2230	LogFlowFunc(("pBackendData=%#p Uuid=%RTuuid\n", pBackendData, pUuid));
2231	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2232
2233	AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
2234
2235	int rc;
2236	if (pImage->uOpenFlags & VD_OPEN_FLAGS_READONLY)
2237	rc = VERR_VD_IMAGE_READ_ONLY;
2238	else
2239	rc = VERR_NOT_SUPPORTED;
2240
2241	LogFlowFunc(("returns %Rrc\n", rc));
2242	return rc;
2243	}
2244
2245	/** @interface_method_impl{VDIMAGEBACKEND,pfnDump} */
2246	static DECLCALLBACK(void) vhdDump(void *pBackendData)
2247	{
2248	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2249
2250	AssertPtrReturnVoid(pImage);
2251	vdIfErrorMessage(pImage->pIfError, "Header: Geometry PCHS=%u/%u/%u LCHS=%u/%u/%u cbSector=%u\n",
2252	pImage->PCHSGeometry.cCylinders, pImage->PCHSGeometry.cHeads, pImage->PCHSGeometry.cSectors,
2253	pImage->LCHSGeometry.cCylinders, pImage->LCHSGeometry.cHeads, pImage->LCHSGeometry.cSectors,
2254	VHD_SECTOR_SIZE);
2255	vdIfErrorMessage(pImage->pIfError, "Header: uuidCreation={%RTuuid}\n", &pImage->ImageUuid);
2256	vdIfErrorMessage(pImage->pIfError, "Header: uuidParent={%RTuuid}\n", &pImage->ParentUuid);
2257	}
2258
2259	/** @interface_method_impl{VDIMAGEBACKEND,pfnGetTimestamp} */
2260	static DECLCALLBACK(int) vhdGetTimestamp(void *pBackendData, PRTTIMESPEC pTimestamp)
2261	{
2262	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2263
2264	AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
2265
2266	int rc = vdIfIoIntFileGetModificationTime(pImage->pIfIo, pImage->pszFilename, pTimestamp);
2267
2268	LogFlowFunc(("returns %Rrc\n", rc));
2269	return rc;
2270	}
2271
2272	/** @interface_method_impl{VDIMAGEBACKEND,pfnGetParentTimestamp} */
2273	static DECLCALLBACK(int) vhdGetParentTimestamp(void *pBackendData, PRTTIMESPEC pTimestamp)
2274	{
2275	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2276
2277	AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
2278
2279	vhdTime2RtTime(pTimestamp, pImage->u32ParentTimestamp);
2280	LogFlowFunc(("returns %Rrc\n", VINF_SUCCESS));
2281	return VINF_SUCCESS;
2282	}
2283
2284	/** @interface_method_impl{VDIMAGEBACKEND,pfnSetParentTimestamp} */
2285	static DECLCALLBACK(int) vhdSetParentTimestamp(void *pBackendData, PCRTTIMESPEC pTimestamp)
2286	{
2287	int rc = VINF_SUCCESS;
2288	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2289
2290	AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
2291	if (pImage->uOpenFlags & VD_OPEN_FLAGS_READONLY)
2292	rc = VERR_VD_IMAGE_READ_ONLY;
2293	else
2294	{
2295	pImage->u32ParentTimestamp = vhdRtTime2VhdTime(pTimestamp);
2296	pImage->fDynHdrNeedsUpdate = true;
2297	}
2298
2299	LogFlowFunc(("returns %Rrc\n", rc));
2300	return rc;
2301	}
2302
2303	/** @interface_method_impl{VDIMAGEBACKEND,pfnGetParentFilename} */
2304	static DECLCALLBACK(int) vhdGetParentFilename(void pBackendData, char *ppszParentFilename)
2305	{
2306	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2307
2308	AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
2309	*ppszParentFilename = RTStrDup(pImage->pszParentFilename);
2310
2311	LogFlowFunc(("returns %Rrc\n", VINF_SUCCESS));
2312	return VINF_SUCCESS;
2313	}
2314
2315	/** @interface_method_impl{VDIMAGEBACKEND,pfnSetParentFilename} */
2316	static DECLCALLBACK(int) vhdSetParentFilename(void pBackendData, const char pszParentFilename)
2317	{
2318	int rc = VINF_SUCCESS;
2319	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2320
2321	AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
2322
2323	if (pImage->uOpenFlags & VD_OPEN_FLAGS_READONLY)
2324	rc = VERR_VD_IMAGE_READ_ONLY;
2325	else
2326	{
2327	if (pImage->pszParentFilename)
2328	RTStrFree(pImage->pszParentFilename);
2329	pImage->pszParentFilename = RTStrDup(pszParentFilename);
2330	if (!pImage->pszParentFilename)
2331	rc = VERR_NO_MEMORY;
2332	else
2333	pImage->fDynHdrNeedsUpdate = true;
2334	}
2335
2336	LogFlowFunc(("returns %Rrc\n", rc));
2337	return rc;
2338	}
2339
2340	/** @interface_method_impl{VDIMAGEBACKEND,pfnCompact} */
2341	static DECLCALLBACK(int) vhdCompact(void *pBackendData, unsigned uPercentStart,
2342	unsigned uPercentSpan, PVDINTERFACE pVDIfsDisk,
2343	PVDINTERFACE pVDIfsImage, PVDINTERFACE pVDIfsOperation)
2344	{
2345	RT_NOREF2(pVDIfsDisk, pVDIfsImage);
2346	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2347	int rc = VINF_SUCCESS;
2348	void *pvBuf = NULL;
2349	uint32_t *paBlocks = NULL;
2350	PVDINTERFACEPROGRESS pIfProgress = VDIfProgressGet(pVDIfsOperation);
2351
2352	PFNVDPARENTREAD pfnParentRead = NULL;
2353	void *pvParent = NULL;
2354	PVDINTERFACEPARENTSTATE pIfParentState = VDIfParentStateGet(pVDIfsOperation);
2355	if (pIfParentState)
2356	{
2357	pfnParentRead = pIfParentState->pfnParentRead;
2358	pvParent = pIfParentState->Core.pvUser;
2359	}
2360
2361	do
2362	{
2363	AssertBreakStmt(pImage, rc = VERR_INVALID_PARAMETER);
2364
2365	AssertBreakStmt(!(pImage->uOpenFlags & VD_OPEN_FLAGS_READONLY),
2366	rc = VERR_VD_IMAGE_READ_ONLY);
2367
2368	/* Reject fixed images as they don't have a BAT. */
2369	if (pImage->uImageFlags & VD_IMAGE_FLAGS_FIXED)
2370	{
2371	rc = VERR_NOT_SUPPORTED;
2372	break;
2373	}
2374
2375	if (pfnParentRead)
2376	{
2377	pvParent = RTMemTmpAlloc(pImage->cbDataBlock);
2378	AssertBreakStmt(pvParent, rc = VERR_NO_MEMORY);
2379	}
2380	pvBuf = RTMemTmpAlloc(pImage->cbDataBlock);
2381	AssertBreakStmt(pvBuf, rc = VERR_NO_MEMORY);
2382
2383	unsigned cBlocksAllocated = 0;
2384	unsigned cBlocksToMove = 0;
2385	unsigned cBlocks = pImage->cBlockAllocationTableEntries;
2386	uint32_t offBlocksStart = ~0U; /* Start offset of data blocks in sectors. */
2387	uint32_t *paBat = pImage->pBlockAllocationTable;
2388
2389	/* Count the number of allocated blocks and find the start offset for the data blocks. */
2390	for (unsigned i = 0; i < cBlocks; i++)
2391	if (paBat[i] != ~0U)
2392	{
2393	cBlocksAllocated++;
2394	if (paBat[i] < offBlocksStart)
2395	offBlocksStart = paBat[i];
2396	}
2397
2398	if (!cBlocksAllocated)
2399	{
2400	/* Nothing to do. */
2401	rc = VINF_SUCCESS;
2402	break;
2403	}
2404
2405	paBlocks = (uint32_t )RTMemTmpAllocZ(cBlocksAllocated sizeof(uint32_t));
2406	AssertBreakStmt(paBlocks, rc = VERR_NO_MEMORY);
2407
2408	/* Invalidate the back resolving array. */
2409	for (unsigned i = 0; i < cBlocksAllocated; i++)
2410	paBlocks[i] = ~0U;
2411
2412	/* Fill the back resolving table. */
2413	for (unsigned i = 0; i < cBlocks; i++)
2414	if (paBat[i] != ~0U)
2415	{
2416	unsigned idxBlock = (paBat[i] - offBlocksStart) / pImage->cSectorsPerDataBlock;
2417	if ( idxBlock < cBlocksAllocated
2418	&& paBlocks[idxBlock] == ~0U)
2419	paBlocks[idxBlock] = i;
2420	else
2421	{
2422	/* The image is in an inconsistent state. Don't go further. */
2423	rc = VERR_INVALID_STATE;
2424	break;
2425	}
2426	}
2427
2428	if (RT_FAILURE(rc))
2429	break;
2430
2431	/* Find redundant information and update the block pointers
2432	* accordingly, creating bubbles. Keep disk up to date, as this
2433	* enables cancelling. */
2434	for (unsigned i = 0; i < cBlocks; i++)
2435	{
2436	if (paBat[i] != ~0U)
2437	{
2438	unsigned idxBlock = (paBat[i] - offBlocksStart) / pImage->cSectorsPerDataBlock;
2439
2440	/* Block present in image file, read relevant data. */
2441	uint64_t u64Offset = ((uint64_t)paBat[i] + pImage->cDataBlockBitmapSectors) * VHD_SECTOR_SIZE;
2442	rc = vdIfIoIntFileReadSync(pImage->pIfIo, pImage->pStorage,
2443	u64Offset, pvBuf, pImage->cbDataBlock);
2444	if (RT_FAILURE(rc))
2445	break;
2446
2447	if (ASMBitFirstSet((volatile void )pvBuf, (uint32_t)pImage->cbDataBlock 8) == -1)
2448	{
2449	paBat[i] = UINT32_MAX;
2450	paBlocks[idxBlock] = ~0U;
2451	/* Adjust progress info, one block to be relocated. */
2452	cBlocksToMove++;
2453	}
2454	else if (pfnParentRead)
2455	{
2456	rc = pfnParentRead(pvParent, (uint64_t)i * pImage->cbDataBlock, pvParent, pImage->cbDataBlock);
2457	if (RT_FAILURE(rc))
2458	break;
2459	if (!memcmp(pvParent, pvBuf, pImage->cbDataBlock))
2460	{
2461	paBat[i] = ~0U;
2462	paBlocks[idxBlock] = ~0U;
2463	/* Adjust progress info, one block to be relocated. */
2464	cBlocksToMove++;
2465	}
2466	}
2467	}
2468
2469	vdIfProgress(pIfProgress, (uint64_t)i * uPercentSpan / (cBlocks + cBlocksToMove) + uPercentStart);
2470	}
2471
2472	if (RT_SUCCESS(rc))
2473	{
2474	/* Fill bubbles with other data (if available). */
2475	unsigned cBlocksMoved = 0;
2476	unsigned uBlockUsedPos = cBlocksAllocated;
2477	size_t cbBlock = pImage->cbDataBlock + pImage->cbDataBlockBitmap; /** < Size of whole block containing the bitmap and the user data. */
2478
2479	/* Allocate data buffer to hold the data block and allocation bitmap in front of the actual data. */
2480	RTMemTmpFree(pvBuf);
2481	pvBuf = RTMemTmpAllocZ(cbBlock);
2482	AssertBreakStmt(pvBuf, rc = VERR_NO_MEMORY);
2483
2484	for (unsigned i = 0; i < cBlocksAllocated; i++)
2485	{
2486	unsigned uBlock = paBlocks[i];
2487	if (uBlock == ~0U)
2488	{
2489	unsigned uBlockData = ~0U;
2490	while (uBlockUsedPos > i && uBlockData == ~0U)
2491	{
2492	uBlockUsedPos--;
2493	uBlockData = paBlocks[uBlockUsedPos];
2494	}
2495	/* Terminate early if there is no block which needs copying. */
2496	if (uBlockUsedPos == i)
2497	break;
2498	uint64_t u64Offset = (uint64_t)uBlockUsedPos * cbBlock
2499	+ (offBlocksStart * VHD_SECTOR_SIZE);
2500	rc = vdIfIoIntFileReadSync(pImage->pIfIo, pImage->pStorage,
2501	u64Offset, pvBuf, cbBlock);
2502	if (RT_FAILURE(rc))
2503	break;
2504
2505	u64Offset = (uint64_t)i * cbBlock
2506	+ (offBlocksStart * VHD_SECTOR_SIZE);
2507	rc = vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage,
2508	u64Offset, pvBuf, cbBlock);
2509	if (RT_FAILURE(rc))
2510	break;
2511
2512	paBat[uBlockData] = i*(pImage->cSectorsPerDataBlock + pImage->cDataBlockBitmapSectors) + offBlocksStart;
2513
2514	/* Truncate the file but leave enough room for the footer to avoid
2515	* races if other processes fill the whole harddisk. */
2516	rc = vdIfIoIntFileSetSize(pImage->pIfIo, pImage->pStorage,
2517	pImage->uCurrentEndOfFile - cbBlock + VHD_SECTOR_SIZE);
2518	if (RT_FAILURE(rc))
2519	break;
2520
2521	/* Update pointers and write footer. */
2522	pImage->uCurrentEndOfFile -= cbBlock;
2523
2524	/* We're kinda screwed if this failes. */
2525	rc = vhdUpdateFooter(pImage);
2526	if (RT_FAILURE(rc))
2527	break;
2528
2529	paBlocks[i] = uBlockData;
2530	paBlocks[uBlockUsedPos] = ~0U;
2531	cBlocksMoved++;
2532	}
2533
2534	rc = vdIfProgress(pIfProgress, (uint64_t)(cBlocks + cBlocksMoved) * uPercentSpan / (cBlocks + cBlocksToMove) + uPercentStart);
2535	}
2536	}
2537
2538	/* Write the new BAT in any case. */
2539	rc = vhdFlushImage(pImage);
2540	} while (0);
2541
2542	if (paBlocks)
2543	RTMemTmpFree(paBlocks);
2544	if (pvParent)
2545	RTMemTmpFree(pvParent);
2546	if (pvBuf)
2547	RTMemTmpFree(pvBuf);
2548
2549	if (RT_SUCCESS(rc))
2550	vdIfProgress(pIfProgress, uPercentStart + uPercentSpan);
2551
2552	LogFlowFunc(("returns %Rrc\n", rc));
2553	return rc;
2554	}
2555
2556	/** @interface_method_impl{VDIMAGEBACKEND,pfnResize} */
2557	static DECLCALLBACK(int) vhdResize(void *pBackendData, uint64_t cbSize,
2558	PCVDGEOMETRY pPCHSGeometry, PCVDGEOMETRY pLCHSGeometry,
2559	unsigned uPercentStart, unsigned uPercentSpan,
2560	PVDINTERFACE pVDIfsDisk, PVDINTERFACE pVDIfsImage,
2561	PVDINTERFACE pVDIfsOperation)
2562	{
2563	RT_NOREF5(uPercentSpan, uPercentStart, pVDIfsDisk, pVDIfsImage, pVDIfsOperation);
2564	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2565	int rc = VINF_SUCCESS;
2566
2567	/* Making the image smaller is not supported at the moment. */
2568	if (cbSize < pImage->cbSize)
2569	rc = VERR_VD_SHRINK_NOT_SUPPORTED;
2570	else if (pImage->uImageFlags & VD_IMAGE_FLAGS_FIXED)
2571	rc = VERR_NOT_SUPPORTED;
2572	else if (cbSize > pImage->cbSize)
2573	{
2574	unsigned cBlocksAllocated = 0;
2575	size_t cbBlock = pImage->cbDataBlock + pImage->cbDataBlockBitmap; /** < Size of a block including the sector bitmap. */
2576	uint32_t cBlocksNew = cbSize / pImage->cbDataBlock; /** < New number of blocks in the image after the resize */
2577	if (cbSize % pImage->cbDataBlock)
2578	cBlocksNew++;
2579
2580	uint32_t cBlocksOld = pImage->cBlockAllocationTableEntries; /** < Number of blocks before the resize. */
2581	uint64_t cbBlockspaceNew = RT_ALIGN_32(cBlocksNew * sizeof(uint32_t), VHD_SECTOR_SIZE); /** < Required space for the block array after the resize. */
2582	uint64_t offStartDataNew = RT_ALIGN_32(pImage->uBlockAllocationTableOffset + cbBlockspaceNew, VHD_SECTOR_SIZE); /** < New start offset for block data after the resize */
2583	uint64_t offStartDataOld = ~0ULL;
2584
2585	/* Go through the BAT and find the data start offset. */
2586	for (unsigned idxBlock = 0; idxBlock < pImage->cBlockAllocationTableEntries; idxBlock++)
2587	{
2588	if (pImage->pBlockAllocationTable[idxBlock] != ~0U)
2589	{
2590	uint64_t offStartBlock = (uint64_t)pImage->pBlockAllocationTable[idxBlock] * VHD_SECTOR_SIZE;
2591	if (offStartBlock < offStartDataOld)
2592	offStartDataOld = offStartBlock;
2593	cBlocksAllocated++;
2594	}
2595	}
2596
2597	if ( offStartDataOld != offStartDataNew
2598	&& cBlocksAllocated > 0)
2599	{
2600	/* Calculate how many sectors nee to be relocated. */
2601	uint64_t cbOverlapping = offStartDataNew - offStartDataOld;
2602	unsigned cBlocksReloc = (unsigned)(cbOverlapping / cbBlock);
2603	if (cbOverlapping % cbBlock)
2604	cBlocksReloc++;
2605
2606	cBlocksReloc = RT_MIN(cBlocksReloc, cBlocksAllocated);
2607	offStartDataNew = offStartDataOld;
2608
2609	/* Do the relocation. */
2610	LogFlow(("Relocating %u blocks\n", cBlocksReloc));
2611
2612	/*
2613	* Get the blocks we need to relocate first, they are appended to the end
2614	* of the image.
2615	*/
2616	void pvBuf = NULL, pvZero = NULL;
2617	do
2618	{
2619	/* Allocate data buffer. */
2620	pvBuf = RTMemAllocZ(cbBlock);
2621	if (!pvBuf)
2622	{
2623	rc = VERR_NO_MEMORY;
2624	break;
2625	}
2626
2627	/* Allocate buffer for overwriting with zeroes. */
2628	pvZero = RTMemAllocZ(cbBlock);
2629	if (!pvZero)
2630	{
2631	rc = VERR_NO_MEMORY;
2632	break;
2633	}
2634
2635	for (unsigned i = 0; i < cBlocksReloc; i++)
2636	{
2637	uint32_t uBlock = offStartDataNew / VHD_SECTOR_SIZE;
2638
2639	/* Search the index in the block table. */
2640	for (unsigned idxBlock = 0; idxBlock < cBlocksOld; idxBlock++)
2641	{
2642	if (pImage->pBlockAllocationTable[idxBlock] == uBlock)
2643	{
2644	/* Read data and append to the end of the image. */
2645	rc = vdIfIoIntFileReadSync(pImage->pIfIo, pImage->pStorage,
2646	offStartDataNew, pvBuf, cbBlock);
2647	if (RT_FAILURE(rc))
2648	break;
2649
2650	rc = vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage,
2651	pImage->uCurrentEndOfFile, pvBuf, cbBlock);
2652	if (RT_FAILURE(rc))
2653	break;
2654
2655	/* Zero out the old block area. */
2656	rc = vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage,
2657	offStartDataNew, pvZero, cbBlock);
2658	if (RT_FAILURE(rc))
2659	break;
2660
2661	/* Update block counter. */
2662	pImage->pBlockAllocationTable[idxBlock] = pImage->uCurrentEndOfFile / VHD_SECTOR_SIZE;
2663
2664	pImage->uCurrentEndOfFile += cbBlock;
2665
2666	/* Continue with the next block. */
2667	break;
2668	}
2669	}
2670
2671	if (RT_FAILURE(rc))
2672	break;
2673
2674	offStartDataNew += cbBlock;
2675	}
2676	} while (0);
2677
2678	if (pvBuf)
2679	RTMemFree(pvBuf);
2680	if (pvZero)
2681	RTMemFree(pvZero);
2682	}
2683
2684	/*
2685	* Relocation done, expand the block array and update the header with
2686	* the new data.
2687	*/
2688	if (RT_SUCCESS(rc))
2689	{
2690	uint32_t paBlocksNew = (uint32_t )RTMemRealloc(pImage->pBlockAllocationTable, cBlocksNew * sizeof(uint32_t));
2691	if (paBlocksNew)
2692	{
2693	pImage->pBlockAllocationTable = paBlocksNew;
2694
2695	/* Mark the new blocks as unallocated. */
2696	for (unsigned idxBlock = cBlocksOld; idxBlock < cBlocksNew; idxBlock++)
2697	pImage->pBlockAllocationTable[idxBlock] = ~0U;
2698	}
2699	else
2700	rc = VERR_NO_MEMORY;
2701
2702	if (RT_SUCCESS(rc))
2703	{
2704	/* Write the block array before updating the rest. */
2705	rc = vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage,
2706	pImage->uBlockAllocationTableOffset,
2707	pImage->pBlockAllocationTable,
2708	cBlocksNew * sizeof(uint32_t));
2709	}
2710
2711	if (RT_SUCCESS(rc))
2712	{
2713	/* Update size and new block count. */
2714	pImage->cBlockAllocationTableEntries = cBlocksNew;
2715	pImage->cbSize = cbSize;
2716
2717	/* Update geometry. */
2718	pImage->PCHSGeometry = *pPCHSGeometry;
2719	pImage->LCHSGeometry = *pLCHSGeometry;
2720	}
2721	}
2722
2723	/* Update header information in base image file. */
2724	pImage->fDynHdrNeedsUpdate = true;
2725	vhdFlushImage(pImage);
2726	}
2727	/* Same size doesn't change the image at all. */
2728
2729	LogFlowFunc(("returns %Rrc\n", rc));
2730	return rc;
2731	}
2732
2733	/** @interface_method_impl{VDIMAGEBACKEND,pfnRepair} */
2734	static DECLCALLBACK(int) vhdRepair(const char *pszFilename, PVDINTERFACE pVDIfsDisk,
2735	PVDINTERFACE pVDIfsImage, uint32_t fFlags)
2736	{
2737	LogFlowFunc(("pszFilename=\"%s\" pVDIfsDisk=%#p pVDIfsImage=%#p\n", pszFilename, pVDIfsDisk, pVDIfsImage));
2738	int rc;
2739	PVDINTERFACEERROR pIfError;
2740	PVDINTERFACEIOINT pIfIo;
2741	PVDIOSTORAGE pStorage = NULL;
2742	uint64_t cbFile;
2743	VHDFooter vhdFooter;
2744	VHDDynamicDiskHeader dynamicDiskHeader;
2745	uint32_t *paBat = NULL;
2746	uint32_t *pu32BlockBitmap = NULL;
2747
2748	pIfIo = VDIfIoIntGet(pVDIfsImage);
2749	AssertPtrReturn(pIfIo, VERR_INVALID_PARAMETER);
2750
2751	pIfError = VDIfErrorGet(pVDIfsDisk);
2752
2753	do
2754	{
2755	uint64_t offDynamicDiskHeader = 0;
2756	uint64_t offBat = 0;
2757	uint64_t offFooter = 0;
2758	uint32_t cBatEntries = 0;
2759	bool fDynamic = false;
2760	bool fRepairFooter = false;
2761	bool fRepairBat = false;
2762	bool fRepairDynHeader = false;
2763
2764	rc = vdIfIoIntFileOpen(pIfIo, pszFilename,
2765	VDOpenFlagsToFileOpenFlags( fFlags & VD_REPAIR_DRY_RUN
2766	? VD_OPEN_FLAGS_READONLY
2767	: 0,
2768	false /* fCreate */),
2769	&pStorage);
2770	if (RT_FAILURE(rc))
2771	{
2772	rc = vdIfError(pIfError, rc, RT_SRC_POS, "Failed to open image \"%s\"", pszFilename);
2773	break;
2774	}
2775
2776	rc = vdIfIoIntFileGetSize(pIfIo, pStorage, &cbFile);
2777	if (RT_FAILURE(rc))
2778	{
2779	rc = vdIfError(pIfError, rc, RT_SRC_POS, "Failed to query image size");
2780	break;
2781	}
2782
2783	if (cbFile < sizeof(VHDFooter))
2784	{
2785	rc = vdIfError(pIfError, VERR_VD_INVALID_SIZE, RT_SRC_POS,
2786	"Image must be at least %u bytes (got %llu)",
2787	sizeof(VHDFooter), cbFile);
2788	break;
2789	}
2790
2791	rc = vdIfIoIntFileReadSync(pIfIo, pStorage, cbFile - sizeof(VHDFooter),
2792	&vhdFooter, sizeof(VHDFooter));
2793	if (RT_FAILURE(rc))
2794	{
2795	rc = vdIfError(pIfError, rc, RT_SRC_POS, "Failed to read footer of image");
2796	break;
2797	}
2798
2799	if (memcmp(vhdFooter.Cookie, VHD_FOOTER_COOKIE, VHD_FOOTER_COOKIE_SIZE) != 0)
2800	{
2801	/* Dynamic images have a backup at the beginning of the image. */
2802	rc = vdIfIoIntFileReadSync(pIfIo, pStorage, 0,
2803	&vhdFooter, sizeof(VHDFooter));
2804	if (RT_FAILURE(rc))
2805	{
2806	rc = vdIfError(pIfError, rc, RT_SRC_POS, "Failed to read header of image");
2807	break;
2808	}
2809
2810	/*
2811	* Check for the header, if this fails the image is either completely corrupted
2812	* and impossible to repair or in another format.
2813	*/
2814	if (memcmp(vhdFooter.Cookie, VHD_FOOTER_COOKIE, VHD_FOOTER_COOKIE_SIZE) != 0)
2815	{
2816	rc = vdIfError(pIfError, VERR_VD_IMAGE_REPAIR_IMPOSSIBLE, RT_SRC_POS,
2817	"No valid VHD structures found");
2818	break;
2819	}
2820	else
2821	vdIfErrorMessage(pIfError, "Missing footer structure, using backup\n");
2822
2823	/* Remember to fix the footer structure. */
2824	fRepairFooter = true;
2825	}
2826
2827	offFooter = cbFile - sizeof(VHDFooter);
2828
2829	/* Verify that checksums match. */
2830	uint32_t u32ChkSumOld = RT_BE2H_U32(vhdFooter.Checksum);
2831	vhdFooter.Checksum = 0;
2832	uint32_t u32ChkSum = vhdChecksum(&vhdFooter, sizeof(VHDFooter));
2833
2834	vhdFooter.Checksum = RT_H2BE_U32(u32ChkSum);
2835
2836	if (u32ChkSumOld != u32ChkSum)
2837	{
2838	vdIfErrorMessage(pIfError, "Checksum is invalid (should be %u got %u), repairing\n",
2839	u32ChkSum, u32ChkSumOld);
2840	fRepairFooter = true;
2841	break;
2842	}
2843
2844	switch (RT_BE2H_U32(vhdFooter.DiskType))
2845	{
2846	case VHD_FOOTER_DISK_TYPE_FIXED:
2847	fDynamic = false;
2848	break;
2849	case VHD_FOOTER_DISK_TYPE_DYNAMIC:
2850	fDynamic = true;
2851	break;
2852	case VHD_FOOTER_DISK_TYPE_DIFFERENCING:
2853	fDynamic = true;
2854	break;
2855	default:
2856	{
2857	rc = vdIfError(pIfError, VERR_VD_IMAGE_REPAIR_IMPOSSIBLE, RT_SRC_POS,
2858	"VHD image type %u is not supported",
2859	RT_BE2H_U32(vhdFooter.DiskType));
2860	break;
2861	}
2862	}
2863
2864	/* Load and check dynamic disk header if required. */
2865	if (fDynamic)
2866	{
2867	size_t cbBlock;
2868
2869	offDynamicDiskHeader = RT_BE2H_U64(vhdFooter.DataOffset);
2870	if (offDynamicDiskHeader + sizeof(VHDDynamicDiskHeader) > cbFile)
2871	{
2872	rc = vdIfError(pIfError, VERR_VD_IMAGE_REPAIR_IMPOSSIBLE, RT_SRC_POS,
2873	"VHD image type is not supported");
2874	break;
2875	}
2876
2877	rc = vdIfIoIntFileReadSync(pIfIo, pStorage, offDynamicDiskHeader,
2878	&dynamicDiskHeader, sizeof(VHDDynamicDiskHeader));
2879	if (RT_FAILURE(rc))
2880	{
2881	rc = vdIfError(pIfError, VERR_VD_IMAGE_REPAIR_IMPOSSIBLE, RT_SRC_POS,
2882	"Failed to read dynamic disk header (at %llu), %Rrc",
2883	offDynamicDiskHeader, rc);
2884	break;
2885	}
2886
2887	/* Verify that checksums match. */
2888	u32ChkSumOld = RT_BE2H_U32(dynamicDiskHeader.Checksum);
2889	dynamicDiskHeader.Checksum = 0;
2890	u32ChkSum = vhdChecksum(&dynamicDiskHeader, sizeof(VHDDynamicDiskHeader));
2891
2892	dynamicDiskHeader.Checksum = RT_H2BE_U32(u32ChkSum);
2893
2894	if (u32ChkSumOld != u32ChkSum)
2895	{
2896	vdIfErrorMessage(pIfError, "Checksum of dynamic disk header is invalid (should be %u got %u), repairing\n",
2897	u32ChkSum, u32ChkSumOld);
2898	fRepairDynHeader = true;
2899	break;
2900	}
2901
2902	/* Read the block allocation table and fix any inconsistencies. */
2903	offBat = RT_BE2H_U64(dynamicDiskHeader.TableOffset);
2904	cBatEntries = RT_BE2H_U32(dynamicDiskHeader.MaxTableEntries);
2905	cbBlock = RT_BE2H_U32(dynamicDiskHeader.BlockSize);
2906	cbBlock += cbBlock / VHD_SECTOR_SIZE / 8;
2907
2908	if (offBat + cBatEntries * sizeof(uint32_t) > cbFile)
2909	{
2910	rc = vdIfError(pIfError, VERR_VD_IMAGE_REPAIR_IMPOSSIBLE, RT_SRC_POS,
2911	"Block allocation table is not inside the image");
2912	break;
2913	}
2914
2915	paBat = (uint32_t )RTMemAllocZ(cBatEntries sizeof(uint32_t));
2916	if (!paBat)
2917	{
2918	rc = vdIfError(pIfError, VERR_VD_IMAGE_REPAIR_IMPOSSIBLE, RT_SRC_POS,
2919	"Could not allocate memory for the block allocation table (%u bytes)",
2920	cBatEntries * sizeof(uint32_t));
2921	break;
2922	}
2923
2924	rc = vdIfIoIntFileReadSync(pIfIo, pStorage, offBat, paBat,
2925	cBatEntries * sizeof(uint32_t));
2926	if (RT_FAILURE(rc))
2927	{
2928	rc = vdIfError(pIfError, VERR_VD_IMAGE_REPAIR_IMPOSSIBLE, RT_SRC_POS,
2929	"Could not read block allocation table (at %llu), %Rrc",
2930	offBat, rc);
2931	break;
2932	}
2933
2934	pu32BlockBitmap = (uint32_t *)RTMemAllocZ(RT_ALIGN_Z(cBatEntries / 8, 4));
2935	if (!pu32BlockBitmap)
2936	{
2937	rc = vdIfError(pIfError, VERR_NO_MEMORY, RT_SRC_POS,
2938	"Failed to allocate memory for block bitmap");
2939	break;
2940	}
2941
2942	uint32_t idxMinBlock = UINT32_C(0xffffffff);
2943	for (uint32_t i = 0; i < cBatEntries; i++)
2944	{
2945	paBat[i] = RT_BE2H_U32(paBat[i]);
2946	if (paBat[i] < idxMinBlock)
2947	idxMinBlock = paBat[i];
2948	}
2949
2950	vdIfErrorMessage(pIfError, "First data block at sector %u\n", idxMinBlock);
2951
2952	for (uint32_t i = 0; i < cBatEntries; i++)
2953	{
2954	if (paBat[i] != UINT32_C(0xffffffff))
2955	{
2956	uint64_t offBlock =(uint64_t)paBat[i] * VHD_SECTOR_SIZE;
2957
2958	/*
2959	* Check that the offsets are valid (inside of the image) and
2960	* that there are no double references.
2961	*/
2962	if (offBlock + cbBlock > cbFile)
2963	{
2964	vdIfErrorMessage(pIfError, "Entry %u points to invalid offset %llu, clearing\n",
2965	i, offBlock);
2966	paBat[i] = UINT32_C(0xffffffff);
2967	fRepairBat = true;
2968	}
2969	else if (offBlock + cbBlock > offFooter)
2970	{
2971	vdIfErrorMessage(pIfError, "Entry %u intersects with footer, aligning footer\n",
2972	i);
2973	offFooter = offBlock + cbBlock;
2974	fRepairBat = true;
2975	}
2976
2977	if ( paBat[i] != UINT32_C(0xffffffff)
2978	&& ASMBitTestAndSet(pu32BlockBitmap, (uint32_t)((paBat[i] - idxMinBlock) / (cbBlock / VHD_SECTOR_SIZE))))
2979	{
2980	vdIfErrorMessage(pIfError, "Entry %u points to an already referenced data block, clearing\n",
2981	i);
2982	paBat[i] = UINT32_C(0xffffffff);
2983	fRepairBat = true;
2984	}
2985	}
2986	}
2987	}
2988
2989	/* Write repaired structures now. */
2990	if (!(fRepairBat \|\| fRepairDynHeader \|\| fRepairFooter))
2991	vdIfErrorMessage(pIfError, "VHD image is in a consistent state, no repair required\n");
2992	else if (!(fFlags & VD_REPAIR_DRY_RUN))
2993	{
2994	if (fRepairBat)
2995	{
2996	for (uint32_t i = 0; i < cBatEntries; i++)
2997	paBat[i] = RT_H2BE_U32(paBat[i]);
2998
2999	vdIfErrorMessage(pIfError, "Writing repaired block allocation table...\n");
3000
3001	rc = vdIfIoIntFileWriteSync(pIfIo, pStorage, offBat, paBat,
3002	cBatEntries * sizeof(uint32_t));
3003	if (RT_FAILURE(rc))
3004	{
3005	rc = vdIfError(pIfError, VERR_VD_IMAGE_REPAIR_IMPOSSIBLE, RT_SRC_POS,
3006	"Could not write repaired block allocation table (at %llu), %Rrc",
3007	offBat, rc);
3008	break;
3009	}
3010	}
3011
3012	if (fRepairDynHeader)
3013	{
3014	Assert(fDynamic);
3015
3016	vdIfErrorMessage(pIfError, "Writing repaired dynamic disk header...\n");
3017	rc = vdIfIoIntFileWriteSync(pIfIo, pStorage, offDynamicDiskHeader, &dynamicDiskHeader,
3018	sizeof(VHDDynamicDiskHeader));
3019	if (RT_FAILURE(rc))
3020	{
3021	rc = vdIfError(pIfError, VERR_VD_IMAGE_REPAIR_IMPOSSIBLE, RT_SRC_POS,
3022	"Could not write repaired dynamic disk header (at %llu), %Rrc",
3023	offDynamicDiskHeader, rc);
3024	break;
3025	}
3026	}
3027
3028	if (fRepairFooter)
3029	{
3030	vdIfErrorMessage(pIfError, "Writing repaired Footer...\n");
3031
3032	if (fDynamic)
3033	{
3034	/* Write backup at image beginning. */
3035	rc = vdIfIoIntFileWriteSync(pIfIo, pStorage, 0, &vhdFooter,
3036	sizeof(VHDFooter));
3037	if (RT_FAILURE(rc))
3038	{
3039	rc = vdIfError(pIfError, VERR_VD_IMAGE_REPAIR_IMPOSSIBLE, RT_SRC_POS,
3040	"Could not write repaired backup footer (at %llu), %Rrc",
3041	0, rc);
3042	break;
3043	}
3044	}
3045
3046	rc = vdIfIoIntFileWriteSync(pIfIo, pStorage, offFooter, &vhdFooter,
3047	sizeof(VHDFooter));
3048	if (RT_FAILURE(rc))
3049	{
3050	rc = vdIfError(pIfError, VERR_VD_IMAGE_REPAIR_IMPOSSIBLE, RT_SRC_POS,
3051	"Could not write repaired footer (at %llu), %Rrc",
3052	cbFile - sizeof(VHDFooter), rc);
3053	break;
3054	}
3055	}
3056
3057	vdIfErrorMessage(pIfError, "Corrupted VHD image repaired successfully\n");
3058	}
3059	} while(0);
3060
3061	if (paBat)
3062	RTMemFree(paBat);
3063
3064	if (pu32BlockBitmap)
3065	RTMemFree(pu32BlockBitmap);
3066
3067	if (pStorage)
3068	{
3069	int rc2 = vdIfIoIntFileClose(pIfIo, pStorage);
3070	if (RT_SUCCESS(rc))
3071	rc = rc2; /* Propagate status code only when repairing the image was successful. */
3072	}
3073
3074	LogFlowFunc(("returns %Rrc\n", rc));
3075	return rc;
3076	}
3077
3078
3079	const VDIMAGEBACKEND g_VhdBackend =
3080	{
3081	/* u32Version */
3082	VD_IMGBACKEND_VERSION,
3083	/* pszBackendName */
3084	"VHD",
3085	/* uBackendCaps */
3086	VD_CAP_UUID \| VD_CAP_DIFF \| VD_CAP_FILE \|
3087	VD_CAP_CREATE_FIXED \| VD_CAP_CREATE_DYNAMIC \|
3088	VD_CAP_ASYNC \| VD_CAP_VFS \| VD_CAP_PREFERRED,
3089	/* paFileExtensions */
3090	s_aVhdFileExtensions,
3091	/* paConfigInfo */
3092	NULL,
3093	/* pfnProbe */
3094	vhdProbe,
3095	/* pfnOpen */
3096	vhdOpen,
3097	/* pfnCreate */
3098	vhdCreate,
3099	/* pfnRename */
3100	vhdRename,
3101	/* pfnClose */
3102	vhdClose,
3103	/* pfnRead */
3104	vhdRead,
3105	/* pfnWrite */
3106	vhdWrite,
3107	/* pfnFlush */
3108	vhdFlush,
3109	/* pfnDiscard */
3110	NULL,
3111	/* pfnGetVersion */
3112	vhdGetVersion,
3113	/* pfnGetFileSize */
3114	vhdGetFileSize,
3115	/* pfnGetPCHSGeometry */
3116	vhdGetPCHSGeometry,
3117	/* pfnSetPCHSGeometry */
3118	vhdSetPCHSGeometry,
3119	/* pfnGetLCHSGeometry */
3120	vhdGetLCHSGeometry,
3121	/* pfnSetLCHSGeometry */
3122	vhdSetLCHSGeometry,
3123	/* pfnQueryRegions */
3124	vhdQueryRegions,
3125	/* pfnRegionListRelease */
3126	vhdRegionListRelease,
3127	/* pfnGetImageFlags */
3128	vhdGetImageFlags,
3129	/* pfnGetOpenFlags */
3130	vhdGetOpenFlags,
3131	/* pfnSetOpenFlags */
3132	vhdSetOpenFlags,
3133	/* pfnGetComment */
3134	vhdGetComment,
3135	/* pfnSetComment */
3136	vhdSetComment,
3137	/* pfnGetUuid */
3138	vhdGetUuid,
3139	/* pfnSetUuid */
3140	vhdSetUuid,
3141	/* pfnGetModificationUuid */
3142	vhdGetModificationUuid,
3143	/* pfnSetModificationUuid */
3144	vhdSetModificationUuid,
3145	/* pfnGetParentUuid */
3146	vhdGetParentUuid,
3147	/* pfnSetParentUuid */
3148	vhdSetParentUuid,
3149	/* pfnGetParentModificationUuid */
3150	vhdGetParentModificationUuid,
3151	/* pfnSetParentModificationUuid */
3152	vhdSetParentModificationUuid,
3153	/* pfnDump */
3154	vhdDump,
3155	/* pfnGetTimestamp */
3156	vhdGetTimestamp,
3157	/* pfnGetParentTimestamp */
3158	vhdGetParentTimestamp,
3159	/* pfnSetParentTimestamp */
3160	vhdSetParentTimestamp,
3161	/* pfnGetParentFilename */
3162	vhdGetParentFilename,
3163	/* pfnSetParentFilename */
3164	vhdSetParentFilename,
3165	/* pfnComposeLocation */
3166	genericFileComposeLocation,
3167	/* pfnComposeName */
3168	genericFileComposeName,
3169	/* pfnCompact */
3170	vhdCompact,
3171	/* pfnResize */
3172	vhdResize,
3173	/* pfnRepair */
3174	vhdRepair,
3175	/* pfnTraverseMetadata */
3176	NULL,
3177	/* u32VersionEnd */
3178	VD_IMGBACKEND_VERSION
3179	};

Note: See TracBrowser for help on using the repository browser.

source: vbox/trunk/src/VBox/Storage/VHD.cpp@ 98103

Download in other formats: