VHD.cpp@ 90802

Last change on this file since 90802 was 90802, checked in by vboxsync, 3 years ago
Storage: More VALID_PTR -> RT_VALID_PTR/AssertPtr.
Property svn:eol-style set to `native` Property svn:keywords set to `Author Date Id Revision`
File size: 119.2 KB

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1	/* $Id: VHD.cpp 90802 2021-08-23 19:08:27Z vboxsync $ */
2	/** @file
3	* VHD Disk image, Core Code.
4	*/
5
6	/*
7	* Copyright (C) 2006-2020 Oracle Corporation
8	*
9	* This file is part of VirtualBox Open Source Edition (OSE), as
10	* available from http://www.virtualbox.org. This file is free software;
11	* you can redistribute it and/or modify it under the terms of the GNU
12	* General Public License (GPL) as published by the Free Software
13	* Foundation, in version 2 as it comes in the "COPYING" file of the
14	* VirtualBox OSE distribution. VirtualBox OSE is distributed in the
15	* hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
16	*/
17
18
19	/*********************************************************************************************************************************
20	* Header Files *
21	*********************************************************************************************************************************/
22	#define LOG_GROUP LOG_GROUP_VD_VHD
23	#include <VBox/vd-plugin.h>
24	#include <VBox/err.h>
25
26	#include <VBox/log.h>
27	#include <VBox/version.h>
28	#include <iprt/asm.h>
29	#include <iprt/assert.h>
30	#include <iprt/mem.h>
31	#include <iprt/uuid.h>
32	#include <iprt/path.h>
33	#include <iprt/string.h>
34	#include <iprt/utf16.h>
35
36	#include "VDBackends.h"
37
38	#define VHD_RELATIVE_MAX_PATH 512
39	#define VHD_ABSOLUTE_MAX_PATH 512
40
41	#define VHD_SECTOR_SIZE 512
42	#define VHD_BLOCK_SIZE (2 * _1M)
43
44	/** The maximum VHD size is 2TB due to the 32bit sector numbers in the BAT.
45	* Note that this is the maximum file size including all footers and headers
46	* and not the maximum virtual disk size presented to the guest.
47	*/
48	#define VHD_MAX_SIZE (2 * _1T)
49	/** Maximum number of 512 byte sectors for a VHD image. */
50	#define VHD_MAX_SECTORS (VHD_MAX_SIZE / VHD_SECTOR_SIZE)
51
52	/* This is common to all VHD disk types and is located at the end of the image */
53	#pragma pack(1)
54	typedef struct VHDFooter
55	{
56	char Cookie[8];
57	uint32_t Features;
58	uint32_t Version;
59	uint64_t DataOffset;
60	uint32_t Timestamp;
61	uint8_t CreatorApp[4];
62	uint32_t CreatorVer;
63	uint32_t CreatorOS;
64	uint64_t OrigSize;
65	uint64_t CurSize;
66	uint16_t DiskGeometryCylinder;
67	uint8_t DiskGeometryHeads;
68	uint8_t DiskGeometrySectors;
69	uint32_t DiskType;
70	uint32_t Checksum;
71	char UniqueID[16];
72	uint8_t SavedState;
73	uint8_t Reserved[427];
74	} VHDFooter;
75	#pragma pack()
76
77	/* this really is spelled with only one n */
78	#define VHD_FOOTER_COOKIE "conectix"
79	#define VHD_FOOTER_COOKIE_SIZE 8
80
81	#define VHD_FOOTER_FEATURES_NOT_ENABLED 0
82	#define VHD_FOOTER_FEATURES_TEMPORARY 1
83	#define VHD_FOOTER_FEATURES_RESERVED 2
84
85	#define VHD_FOOTER_FILE_FORMAT_VERSION 0x00010000
86	#define VHD_FOOTER_DATA_OFFSET_FIXED UINT64_C(0xffffffffffffffff)
87	#define VHD_FOOTER_DISK_TYPE_FIXED 2
88	#define VHD_FOOTER_DISK_TYPE_DYNAMIC 3
89	#define VHD_FOOTER_DISK_TYPE_DIFFERENCING 4
90
91	#define VHD_MAX_LOCATOR_ENTRIES 8
92	#define VHD_PLATFORM_CODE_NONE 0
93	#define VHD_PLATFORM_CODE_WI2R 0x57693272
94	#define VHD_PLATFORM_CODE_WI2K 0x5769326B
95	#define VHD_PLATFORM_CODE_W2RU 0x57327275
96	#define VHD_PLATFORM_CODE_W2KU 0x57326B75
97	#define VHD_PLATFORM_CODE_MAC 0x4D163220
98	#define VHD_PLATFORM_CODE_MACX 0x4D163258
99
100	/* Header for expanding disk images. */
101	#pragma pack(1)
102	typedef struct VHDParentLocatorEntry
103	{
104	uint32_t u32Code;
105	uint32_t u32DataSpace;
106	uint32_t u32DataLength;
107	uint32_t u32Reserved;
108	uint64_t u64DataOffset;
109	} VHDPLE, *PVHDPLE;
110
111	typedef struct VHDDynamicDiskHeader
112	{
113	char Cookie[8];
114	uint64_t DataOffset;
115	uint64_t TableOffset;
116	uint32_t HeaderVersion;
117	uint32_t MaxTableEntries;
118	uint32_t BlockSize;
119	uint32_t Checksum;
120	uint8_t ParentUuid[16];
121	uint32_t ParentTimestamp;
122	uint32_t Reserved0;
123	uint16_t ParentUnicodeName[256];
124	VHDPLE ParentLocatorEntry[VHD_MAX_LOCATOR_ENTRIES];
125	uint8_t Reserved1[256];
126	} VHDDynamicDiskHeader;
127	#pragma pack()
128
129	#define VHD_DYNAMIC_DISK_HEADER_COOKIE "cxsparse"
130	#define VHD_DYNAMIC_DISK_HEADER_COOKIE_SIZE 8
131	#define VHD_DYNAMIC_DISK_HEADER_VERSION 0x00010000
132
133	/**
134	* Complete VHD image data structure.
135	*/
136	typedef struct VHDIMAGE
137	{
138	/** Image file name. */
139	const char *pszFilename;
140	/** Opaque storage handle. */
141	PVDIOSTORAGE pStorage;
142
143	/** Pointer to the per-disk VD interface list. */
144	PVDINTERFACE pVDIfsDisk;
145	/** Pointer to the per-image VD interface list. */
146	PVDINTERFACE pVDIfsImage;
147	/** Error interface. */
148	PVDINTERFACEERROR pIfError;
149	/** I/O interface. */
150	PVDINTERFACEIOINT pIfIo;
151
152	/** Open flags passed by VBoxHDD layer. */
153	unsigned uOpenFlags;
154	/** Image flags defined during creation or determined during open. */
155	unsigned uImageFlags;
156	/** Total size of the image. */
157	uint64_t cbSize;
158
159	/** Physical geometry of this image. */
160	VDGEOMETRY PCHSGeometry;
161	/** Logical geometry of this image. */
162	VDGEOMETRY LCHSGeometry;
163
164	/** Image UUID. */
165	RTUUID ImageUuid;
166	/** Parent image UUID. */
167	RTUUID ParentUuid;
168
169	/** Parent's time stamp at the time of image creation. */
170	uint32_t u32ParentTimestamp;
171	/** Relative path to the parent image. */
172	char *pszParentFilename;
173
174	/** The Block Allocation Table. */
175	uint32_t *pBlockAllocationTable;
176	/** Number of entries in the table. */
177	uint32_t cBlockAllocationTableEntries;
178
179	/** Size of one data block. */
180	uint32_t cbDataBlock;
181	/** Sectors per data block. */
182	uint32_t cSectorsPerDataBlock;
183	/** Length of the sector bitmap in bytes. */
184	uint32_t cbDataBlockBitmap;
185	/** A copy of the disk footer. */
186	VHDFooter vhdFooterCopy;
187	/** Current end offset of the file (without the disk footer). */
188	uint64_t uCurrentEndOfFile;
189	/** Size of the data block bitmap in sectors. */
190	uint32_t cDataBlockBitmapSectors;
191	/** Start of the block allocation table. */
192	uint64_t uBlockAllocationTableOffset;
193	/** Buffer to hold block's bitmap for bit search operations. */
194	uint8_t *pu8Bitmap;
195	/** Offset to the next data structure (dynamic disk header). */
196	uint64_t u64DataOffset;
197	/** Flag to force dynamic disk header update. */
198	bool fDynHdrNeedsUpdate;
199	/** The static region list. */
200	VDREGIONLIST RegionList;
201	} VHDIMAGE, *PVHDIMAGE;
202
203	/**
204	* Structure tracking the expansion process of the image
205	* for async access.
206	*/
207	typedef struct VHDIMAGEEXPAND
208	{
209	/** Flag indicating the status of each step. */
210	volatile uint32_t fFlags;
211	/** The index in the block allocation table which is written. */
212	uint32_t idxBatAllocated;
213	/** Big endian representation of the block index
214	* which is written in the BAT. */
215	uint32_t idxBlockBe;
216	/** Old end of the file - used for rollback in case of an error. */
217	uint64_t cbEofOld;
218	/** Sector bitmap written to the new block - variable in size. */
219	uint8_t au8Bitmap[1];
220	} VHDIMAGEEXPAND, *PVHDIMAGEEXPAND;
221
222	/**
223	* Flag defines
224	*/
225	#define VHDIMAGEEXPAND_STEP_IN_PROGRESS (0x0)
226	#define VHDIMAGEEXPAND_STEP_FAILED (0x2)
227	#define VHDIMAGEEXPAND_STEP_SUCCESS (0x3)
228	/** All steps completed successfully. */
229	#define VHDIMAGEEXPAND_ALL_SUCCESS (0xff)
230	/** All steps completed (no success indicator) */
231	#define VHDIMAGEEXPAND_ALL_COMPLETE (0xaa)
232
233	/** Every status field has 2 bits so we can encode 4 steps in one byte. */
234	#define VHDIMAGEEXPAND_STATUS_MASK 0x03
235	#define VHDIMAGEEXPAND_BLOCKBITMAP_STATUS_SHIFT 0x00
236	#define VHDIMAGEEXPAND_USERBLOCK_STATUS_SHIFT 0x02
237	#define VHDIMAGEEXPAND_FOOTER_STATUS_SHIFT 0x04
238	#define VHDIMAGEEXPAND_BAT_STATUS_SHIFT 0x06
239
240	/**
241	* Helper macros to get and set the status field.
242	*/
243	#define VHDIMAGEEXPAND_STATUS_GET(fFlags, cShift) \
244	(((fFlags) >> (cShift)) & VHDIMAGEEXPAND_STATUS_MASK)
245	#define VHDIMAGEEXPAND_STATUS_SET(fFlags, cShift, uVal) \
246	ASMAtomicOrU32(&(fFlags), ((uVal) & VHDIMAGEEXPAND_STATUS_MASK) << (cShift))
247
248
249	/*********************************************************************************************************************************
250	* Static Variables *
251	*********************************************************************************************************************************/
252
253	/** NULL-terminated array of supported file extensions. */
254	static const VDFILEEXTENSION s_aVhdFileExtensions[] =
255	{
256	{"vhd", VDTYPE_HDD},
257	{NULL, VDTYPE_INVALID}
258	};
259
260
261	/*********************************************************************************************************************************
262	* Internal Functions *
263	*********************************************************************************************************************************/
264
265
266	/**
267	* Internal: Compute and update header checksum.
268	*/
269	static uint32_t vhdChecksum(void *pHeader, uint32_t cbSize)
270	{
271	uint32_t u32ChkSum = 0;
272	for (uint32_t i = 0; i < cbSize; i++)
273	u32ChkSum += ((unsigned char *)pHeader)[i];
274	return ~u32ChkSum;
275	}
276
277	/**
278	* Internal: Convert filename to UTF16 with appropriate endianness.
279	*/
280	static int vhdFilenameToUtf16(const char pszFilename, uint16_t pu16Buf,
281	uint32_t cbBufSize, uint32_t *pcbActualSize,
282	bool fBigEndian)
283	{
284	int rc;
285	PRTUTF16 pTmp16 = NULL;
286	size_t cTmp16Len;
287
288	rc = RTStrToUtf16(pszFilename, &pTmp16);
289	if (RT_SUCCESS(rc))
290	{
291	cTmp16Len = RTUtf16Len(pTmp16);
292	if (cTmp16Len * sizeof(*pTmp16) <= cbBufSize)
293	{
294	if (fBigEndian)
295	for (unsigned i = 0; i < cTmp16Len; i++)
296	pu16Buf[i] = RT_H2BE_U16(pTmp16[i]);
297	else
298	memcpy(pu16Buf, pTmp16, cTmp16Len * sizeof(*pTmp16));
299	if (pcbActualSize)
300	pcbActualSize = (uint32_t)(cTmp16Len sizeof(*pTmp16));
301	}
302	else
303	rc = VERR_FILENAME_TOO_LONG;
304	}
305
306	if (pTmp16)
307	RTUtf16Free(pTmp16);
308	return rc;
309	}
310
311	/**
312	* Internal: Update one locator entry.
313	*/
314	static int vhdLocatorUpdate(PVHDIMAGE pImage, PVHDPLE pLocator, const char *pszFilename)
315	{
316	int rc = VINF_SUCCESS;
317	uint32_t cb = 0;
318	uint32_t cbMaxLen = RT_BE2H_U32(pLocator->u32DataSpace);
319	void *pvBuf = RTMemTmpAllocZ(cbMaxLen);
320	char *pszTmp;
321
322	if (!pvBuf)
323	return VERR_NO_MEMORY;
324
325	switch (RT_BE2H_U32(pLocator->u32Code))
326	{
327	case VHD_PLATFORM_CODE_WI2R:
328	{
329	if (RTPathStartsWithRoot(pszFilename))
330	{
331	/* Convert to relative path. */
332	char szPath[RTPATH_MAX];
333	rc = RTPathCalcRelative(szPath, sizeof(szPath), pImage->pszFilename, true /fFromFile/, pszFilename);
334	if (RT_SUCCESS(rc))
335	{
336	/* Update plain relative name. */
337	cb = (uint32_t)strlen(szPath);
338	if (cb > cbMaxLen)
339	{
340	rc = VERR_FILENAME_TOO_LONG;
341	break;
342	}
343	memcpy(pvBuf, szPath, cb);
344	}
345	}
346	else
347	{
348	/* Update plain relative name. */
349	cb = (uint32_t)strlen(pszFilename);
350	if (cb > cbMaxLen)
351	{
352	rc = VERR_FILENAME_TOO_LONG;
353	break;
354	}
355	memcpy(pvBuf, pszFilename, cb);
356	}
357	if (RT_SUCCESS(rc))
358	pLocator->u32DataLength = RT_H2BE_U32(cb);
359	break;
360	}
361	case VHD_PLATFORM_CODE_WI2K:
362	/* Update plain absolute name. */
363	rc = RTPathAbs(pszFilename, (char *)pvBuf, cbMaxLen);
364	if (RT_SUCCESS(rc))
365	{
366	cb = (uint32_t)strlen((const char *)pvBuf);
367	pLocator->u32DataLength = RT_H2BE_U32(cb);
368	}
369	break;
370	case VHD_PLATFORM_CODE_W2RU:
371	if (RTPathStartsWithRoot(pszFilename))
372	{
373	/* Convert to relative path. */
374	char szPath[RTPATH_MAX];
375	rc = RTPathCalcRelative(szPath, sizeof(szPath), pImage->pszFilename, true /fFromFile/, pszFilename);
376	if (RT_SUCCESS(rc))
377	rc = vhdFilenameToUtf16(szPath, (uint16_t *)pvBuf, cbMaxLen, &cb, false);
378	}
379	else
380	{
381	/* Update unicode relative name. */
382	rc = vhdFilenameToUtf16(pszFilename, (uint16_t *)pvBuf, cbMaxLen, &cb, false);
383	}
384
385	if (RT_SUCCESS(rc))
386	pLocator->u32DataLength = RT_H2BE_U32(cb);
387	break;
388	case VHD_PLATFORM_CODE_W2KU:
389	/* Update unicode absolute name. */
390	pszTmp = (char*)RTMemTmpAllocZ(cbMaxLen);
391	if (!pszTmp)
392	{
393	rc = VERR_NO_MEMORY;
394	break;
395	}
396	rc = RTPathAbs(pszFilename, pszTmp, cbMaxLen);
397	if (RT_FAILURE(rc))
398	{
399	RTMemTmpFree(pszTmp);
400	break;
401	}
402	rc = vhdFilenameToUtf16(pszTmp, (uint16_t *)pvBuf, cbMaxLen, &cb, false);
403	RTMemTmpFree(pszTmp);
404	if (RT_SUCCESS(rc))
405	pLocator->u32DataLength = RT_H2BE_U32(cb);
406	break;
407	default:
408	rc = VERR_NOT_IMPLEMENTED;
409	break;
410	}
411
412	if (RT_SUCCESS(rc))
413	{
414	Assert(cb > 0);
415	rc = vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage,
416	RT_BE2H_U64(pLocator->u64DataOffset),
417	pvBuf, cb);
418	}
419
420	if (pvBuf)
421	RTMemTmpFree(pvBuf);
422	return rc;
423	}
424
425	/**
426	* Internal: Update dynamic disk header from VHDIMAGE.
427	*/
428	static int vhdDynamicHeaderUpdate(PVHDIMAGE pImage)
429	{
430	VHDDynamicDiskHeader ddh;
431	int rc, i;
432
433	if (!pImage)
434	return VERR_VD_NOT_OPENED;
435
436	rc = vdIfIoIntFileReadSync(pImage->pIfIo, pImage->pStorage,
437	pImage->u64DataOffset, &ddh, sizeof(ddh));
438	if (RT_FAILURE(rc))
439	return rc;
440	if (memcmp(ddh.Cookie, VHD_DYNAMIC_DISK_HEADER_COOKIE, VHD_DYNAMIC_DISK_HEADER_COOKIE_SIZE) != 0)
441	return VERR_VD_VHD_INVALID_HEADER;
442
443	uint32_t u32Checksum = RT_BE2H_U32(ddh.Checksum);
444	ddh.Checksum = 0;
445	if (u32Checksum != vhdChecksum(&ddh, sizeof(ddh)))
446	return VERR_VD_VHD_INVALID_HEADER;
447
448	/* Update parent's timestamp. */
449	ddh.ParentTimestamp = RT_H2BE_U32(pImage->u32ParentTimestamp);
450	/* Update parent's filename. */
451	if (pImage->pszParentFilename)
452	{
453	rc = vhdFilenameToUtf16(RTPathFilename(pImage->pszParentFilename),
454	ddh.ParentUnicodeName, sizeof(ddh.ParentUnicodeName) - 1, NULL, true);
455	if (RT_FAILURE(rc))
456	return rc;
457	}
458
459	/* Update parent's locators. */
460	for (i = 0; i < VHD_MAX_LOCATOR_ENTRIES; i++)
461	{
462	/* Skip empty locators */
463	if ( ddh.ParentLocatorEntry[i].u32Code != RT_H2BE_U32(VHD_PLATFORM_CODE_NONE)
464	&& pImage->pszParentFilename)
465	{
466	rc = vhdLocatorUpdate(pImage, &ddh.ParentLocatorEntry[i], pImage->pszParentFilename);
467	if (RT_FAILURE(rc))
468	return rc;
469	}
470	}
471	/* Update parent's UUID */
472	memcpy(ddh.ParentUuid, pImage->ParentUuid.au8, sizeof(ddh.ParentUuid));
473
474	/* Update data offset and number of table entries. */
475	ddh.MaxTableEntries = RT_H2BE_U32(pImage->cBlockAllocationTableEntries);
476
477	ddh.Checksum = 0;
478	ddh.Checksum = RT_H2BE_U32(vhdChecksum(&ddh, sizeof(ddh)));
479	rc = vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage,
480	pImage->u64DataOffset, &ddh, sizeof(ddh));
481	return rc;
482	}
483
484	/**
485	* Internal: Update the VHD footer.
486	*/
487	static int vhdUpdateFooter(PVHDIMAGE pImage)
488	{
489	int rc = VINF_SUCCESS;
490
491	/* Update fields which can change. */
492	pImage->vhdFooterCopy.CurSize = RT_H2BE_U64(pImage->cbSize);
493	pImage->vhdFooterCopy.DiskGeometryCylinder = RT_H2BE_U16(pImage->PCHSGeometry.cCylinders);
494	pImage->vhdFooterCopy.DiskGeometryHeads = pImage->PCHSGeometry.cHeads;
495	pImage->vhdFooterCopy.DiskGeometrySectors = pImage->PCHSGeometry.cSectors;
496
497	pImage->vhdFooterCopy.Checksum = 0;
498	pImage->vhdFooterCopy.Checksum = RT_H2BE_U32(vhdChecksum(&pImage->vhdFooterCopy, sizeof(VHDFooter)));
499
500	if (pImage->pBlockAllocationTable)
501	rc = vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage, 0,
502	&pImage->vhdFooterCopy, sizeof(VHDFooter));
503
504	if (RT_SUCCESS(rc))
505	rc = vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage,
506	pImage->uCurrentEndOfFile, &pImage->vhdFooterCopy,
507	sizeof(VHDFooter));
508
509	return rc;
510	}
511
512	/**
513	* Internal. Flush image data to disk.
514	*/
515	static int vhdFlushImage(PVHDIMAGE pImage)
516	{
517	int rc = VINF_SUCCESS;
518
519	if (pImage->uOpenFlags & VD_OPEN_FLAGS_READONLY)
520	return VINF_SUCCESS;
521
522	if (pImage->pBlockAllocationTable)
523	{
524	/*
525	* This is an expanding image. Write the BAT and copy of the disk footer.
526	*/
527	size_t cbBlockAllocationTableToWrite = pImage->cBlockAllocationTableEntries * sizeof(uint32_t);
528	uint32_t pBlockAllocationTableToWrite = (uint32_t )RTMemAllocZ(cbBlockAllocationTableToWrite);
529
530	if (!pBlockAllocationTableToWrite)
531	return VERR_NO_MEMORY;
532
533	/*
534	* The BAT entries have to be stored in big endian format.
535	*/
536	for (unsigned i = 0; i < pImage->cBlockAllocationTableEntries; i++)
537	pBlockAllocationTableToWrite[i] = RT_H2BE_U32(pImage->pBlockAllocationTable[i]);
538
539	/*
540	* Write the block allocation table after the copy of the disk footer and the dynamic disk header.
541	*/
542	vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage, pImage->uBlockAllocationTableOffset,
543	pBlockAllocationTableToWrite, cbBlockAllocationTableToWrite);
544	if (pImage->fDynHdrNeedsUpdate)
545	rc = vhdDynamicHeaderUpdate(pImage);
546	RTMemFree(pBlockAllocationTableToWrite);
547	}
548
549	if (RT_SUCCESS(rc))
550	rc = vhdUpdateFooter(pImage);
551
552	if (RT_SUCCESS(rc))
553	rc = vdIfIoIntFileFlushSync(pImage->pIfIo, pImage->pStorage);
554
555	return rc;
556	}
557
558	/**
559	* Internal. Free all allocated space for representing an image except pImage,
560	* and optionally delete the image from disk.
561	*/
562	static int vhdFreeImage(PVHDIMAGE pImage, bool fDelete)
563	{
564	int rc = VINF_SUCCESS;
565
566	/* Freeing a never allocated image (e.g. because the open failed) is
567	* not signalled as an error. After all nothing bad happens. */
568	if (pImage)
569	{
570	if (pImage->pStorage)
571	{
572	/* No point updating the file that is deleted anyway. */
573	if (!fDelete)
574	vhdFlushImage(pImage);
575
576	rc = vdIfIoIntFileClose(pImage->pIfIo, pImage->pStorage);
577	pImage->pStorage = NULL;
578	}
579
580	if (pImage->pszParentFilename)
581	{
582	RTStrFree(pImage->pszParentFilename);
583	pImage->pszParentFilename = NULL;
584	}
585	if (pImage->pBlockAllocationTable)
586	{
587	RTMemFree(pImage->pBlockAllocationTable);
588	pImage->pBlockAllocationTable = NULL;
589	}
590	if (pImage->pu8Bitmap)
591	{
592	RTMemFree(pImage->pu8Bitmap);
593	pImage->pu8Bitmap = NULL;
594	}
595
596	if (fDelete && pImage->pszFilename)
597	{
598	int rc2 = vdIfIoIntFileDelete(pImage->pIfIo, pImage->pszFilename);
599	if (RT_SUCCESS(rc))
600	rc = rc2;
601	}
602	}
603
604	LogFlowFunc(("returns %Rrc\n", rc));
605	return rc;
606	}
607
608	/* 946684800 is the number of seconds between 1/1/1970 and 1/1/2000 */
609	#define VHD_TO_UNIX_EPOCH_SECONDS UINT64_C(946684800)
610
611	static uint32_t vhdRtTime2VhdTime(PCRTTIMESPEC pRtTimestamp)
612	{
613	uint64_t u64Seconds = RTTimeSpecGetSeconds(pRtTimestamp);
614	return (uint32_t)(u64Seconds - VHD_TO_UNIX_EPOCH_SECONDS);
615	}
616
617	static void vhdTime2RtTime(PRTTIMESPEC pRtTimestamp, uint32_t u32VhdTimestamp)
618	{
619	RTTimeSpecSetSeconds(pRtTimestamp, VHD_TO_UNIX_EPOCH_SECONDS + u32VhdTimestamp);
620	}
621
622	/**
623	* Internal: Allocates the block bitmap rounding up to the next 32bit or 64bit boundary.
624	* Can be freed with RTMemFree. The memory is zeroed.
625	*/
626	DECLINLINE(uint8_t *)vhdBlockBitmapAllocate(PVHDIMAGE pImage)
627	{
628	#ifdef RT_ARCH_AMD64
629	return (uint8_t *)RTMemAllocZ(pImage->cbDataBlockBitmap + 8);
630	#else
631	return (uint8_t *)RTMemAllocZ(pImage->cbDataBlockBitmap + 4);
632	#endif
633	}
634
635	/**
636	* Internal: called when the async expansion process completed (failure or success).
637	* Will do the necessary rollback if an error occurred.
638	*/
639	static int vhdAsyncExpansionComplete(PVHDIMAGE pImage, PVDIOCTX pIoCtx, PVHDIMAGEEXPAND pExpand)
640	{
641	int rc = VINF_SUCCESS;
642	uint32_t fFlags = ASMAtomicReadU32(&pExpand->fFlags);
643	bool fIoInProgress = false;
644
645	/* Quick path, check if everything succeeded. */
646	if (fFlags == VHDIMAGEEXPAND_ALL_SUCCESS)
647	{
648	pImage->pBlockAllocationTable[pExpand->idxBatAllocated] = RT_BE2H_U32(pExpand->idxBlockBe);
649	RTMemFree(pExpand);
650	}
651	else
652	{
653	uint32_t uStatus;
654
655	uStatus = VHDIMAGEEXPAND_STATUS_GET(pExpand->fFlags, VHDIMAGEEXPAND_BAT_STATUS_SHIFT);
656	if ( uStatus == VHDIMAGEEXPAND_STEP_FAILED
657	\|\| uStatus == VHDIMAGEEXPAND_STEP_SUCCESS)
658	{
659	/* Undo and restore the old value. */
660	pImage->pBlockAllocationTable[pExpand->idxBatAllocated] = ~0U;
661
662	/* Restore the old value on the disk.
663	* No need for a completion callback because we can't
664	* do anything if this fails. */
665	if (uStatus == VHDIMAGEEXPAND_STEP_SUCCESS)
666	{
667	rc = vdIfIoIntFileWriteMeta(pImage->pIfIo, pImage->pStorage,
668	pImage->uBlockAllocationTableOffset
669	+ pExpand->idxBatAllocated * sizeof(uint32_t),
670	&pImage->pBlockAllocationTable[pExpand->idxBatAllocated],
671	sizeof(uint32_t), pIoCtx, NULL, NULL);
672	fIoInProgress \|= rc == VERR_VD_ASYNC_IO_IN_PROGRESS;
673	}
674	}
675
676	/* Restore old size (including the footer because another application might
677	* fill up the free space making it impossible to add the footer)
678	* and add the footer at the right place again. */
679	rc = vdIfIoIntFileSetSize(pImage->pIfIo, pImage->pStorage,
680	pExpand->cbEofOld + sizeof(VHDFooter));
681	AssertRC(rc);
682
683	pImage->uCurrentEndOfFile = pExpand->cbEofOld;
684	rc = vdIfIoIntFileWriteMeta(pImage->pIfIo, pImage->pStorage,
685	pImage->uCurrentEndOfFile,
686	&pImage->vhdFooterCopy, sizeof(VHDFooter),
687	pIoCtx, NULL, NULL);
688	fIoInProgress \|= rc == VERR_VD_ASYNC_IO_IN_PROGRESS;
689	}
690
691	return fIoInProgress ? VERR_VD_ASYNC_IO_IN_PROGRESS : rc;
692	}
693
694	static int vhdAsyncExpansionStepCompleted(void pBackendData, PVDIOCTX pIoCtx, void pvUser, int rcReq, unsigned iStep)
695	{
696	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
697	PVHDIMAGEEXPAND pExpand = (PVHDIMAGEEXPAND)pvUser;
698
699	LogFlowFunc(("pBackendData=%#p pIoCtx=%#p pvUser=%#p rcReq=%Rrc iStep=%u\n",
700	pBackendData, pIoCtx, pvUser, rcReq, iStep));
701
702	if (RT_SUCCESS(rcReq))
703	VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, iStep, VHDIMAGEEXPAND_STEP_SUCCESS);
704	else
705	VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, iStep, VHDIMAGEEXPAND_STEP_FAILED);
706
707	if ((pExpand->fFlags & VHDIMAGEEXPAND_ALL_COMPLETE) == VHDIMAGEEXPAND_ALL_COMPLETE)
708	return vhdAsyncExpansionComplete(pImage, pIoCtx, pExpand);
709
710	return VERR_VD_ASYNC_IO_IN_PROGRESS;
711	}
712
713	static DECLCALLBACK(int) vhdAsyncExpansionDataBlockBitmapComplete(void pBackendData, PVDIOCTX pIoCtx, void pvUser, int rcReq)
714	{
715	return vhdAsyncExpansionStepCompleted(pBackendData, pIoCtx, pvUser, rcReq, VHDIMAGEEXPAND_BLOCKBITMAP_STATUS_SHIFT);
716	}
717
718	static DECLCALLBACK(int) vhdAsyncExpansionDataComplete(void pBackendData, PVDIOCTX pIoCtx, void pvUser, int rcReq)
719	{
720	return vhdAsyncExpansionStepCompleted(pBackendData, pIoCtx, pvUser, rcReq, VHDIMAGEEXPAND_USERBLOCK_STATUS_SHIFT);
721	}
722
723	static DECLCALLBACK(int) vhdAsyncExpansionBatUpdateComplete(void pBackendData, PVDIOCTX pIoCtx, void pvUser, int rcReq)
724	{
725	return vhdAsyncExpansionStepCompleted(pBackendData, pIoCtx, pvUser, rcReq, VHDIMAGEEXPAND_BAT_STATUS_SHIFT);
726	}
727
728	static DECLCALLBACK(int) vhdAsyncExpansionFooterUpdateComplete(void pBackendData, PVDIOCTX pIoCtx, void pvUser, int rcReq)
729	{
730	return vhdAsyncExpansionStepCompleted(pBackendData, pIoCtx, pvUser, rcReq, VHDIMAGEEXPAND_FOOTER_STATUS_SHIFT);
731	}
732
733	static int vhdLoadDynamicDisk(PVHDIMAGE pImage, uint64_t uDynamicDiskHeaderOffset)
734	{
735	VHDDynamicDiskHeader vhdDynamicDiskHeader;
736	int rc = VINF_SUCCESS;
737	uint32_t *pBlockAllocationTable;
738	uint64_t uBlockAllocationTableOffset;
739	unsigned i = 0;
740
741	Log(("Open a dynamic disk.\n"));
742
743	/*
744	* Read the dynamic disk header.
745	*/
746	rc = vdIfIoIntFileReadSync(pImage->pIfIo, pImage->pStorage, uDynamicDiskHeaderOffset,
747	&vhdDynamicDiskHeader, sizeof(VHDDynamicDiskHeader));
748	if (memcmp(vhdDynamicDiskHeader.Cookie, VHD_DYNAMIC_DISK_HEADER_COOKIE, VHD_DYNAMIC_DISK_HEADER_COOKIE_SIZE))
749	return VERR_INVALID_PARAMETER;
750
751	pImage->cbDataBlock = RT_BE2H_U32(vhdDynamicDiskHeader.BlockSize);
752	LogFlowFunc(("BlockSize=%u\n", pImage->cbDataBlock));
753	pImage->cBlockAllocationTableEntries = RT_BE2H_U32(vhdDynamicDiskHeader.MaxTableEntries);
754	LogFlowFunc(("MaxTableEntries=%lu\n", pImage->cBlockAllocationTableEntries));
755	AssertMsg(!(pImage->cbDataBlock % VHD_SECTOR_SIZE), ("%s: Data block size is not a multiple of %!\n", __FUNCTION__, VHD_SECTOR_SIZE));
756
757	/*
758	* Bail out if the number of BAT entries exceeds the number of sectors for a maximum image.
759	* Lower the number of sectors in the BAT as a few sectors are already occupied by the footers
760	* and headers.
761	*/
762	if (pImage->cBlockAllocationTableEntries > (VHD_MAX_SECTORS - 2))
763	return VERR_VD_VHD_INVALID_HEADER;
764
765	pImage->cSectorsPerDataBlock = pImage->cbDataBlock / VHD_SECTOR_SIZE;
766	LogFlowFunc(("SectorsPerDataBlock=%u\n", pImage->cSectorsPerDataBlock));
767
768	/*
769	* Every block starts with a bitmap indicating which sectors are valid and which are not.
770	* We store the size of it to be able to calculate the real offset.
771	*/
772	pImage->cbDataBlockBitmap = pImage->cSectorsPerDataBlock / 8;
773	pImage->cDataBlockBitmapSectors = pImage->cbDataBlockBitmap / VHD_SECTOR_SIZE;
774	/* Round up to full sector size */
775	if (pImage->cbDataBlockBitmap % VHD_SECTOR_SIZE > 0)
776	pImage->cDataBlockBitmapSectors++;
777	LogFlowFunc(("cbDataBlockBitmap=%u\n", pImage->cbDataBlockBitmap));
778	LogFlowFunc(("cDataBlockBitmapSectors=%u\n", pImage->cDataBlockBitmapSectors));
779
780	pImage->pu8Bitmap = vhdBlockBitmapAllocate(pImage);
781	if (!pImage->pu8Bitmap)
782	return VERR_NO_MEMORY;
783
784	pBlockAllocationTable = (uint32_t )RTMemAllocZ(pImage->cBlockAllocationTableEntries sizeof(uint32_t));
785	if (!pBlockAllocationTable)
786	return VERR_NO_MEMORY;
787
788	/*
789	* Read the table.
790	*/
791	uBlockAllocationTableOffset = RT_BE2H_U64(vhdDynamicDiskHeader.TableOffset);
792	LogFlowFunc(("uBlockAllocationTableOffset=%llu\n", uBlockAllocationTableOffset));
793	pImage->uBlockAllocationTableOffset = uBlockAllocationTableOffset;
794	rc = vdIfIoIntFileReadSync(pImage->pIfIo, pImage->pStorage,
795	uBlockAllocationTableOffset, pBlockAllocationTable,
796	pImage->cBlockAllocationTableEntries * sizeof(uint32_t));
797	if (RT_FAILURE(rc))
798	{
799	RTMemFree(pBlockAllocationTable);
800	return rc;
801	}
802
803	/*
804	* Because the offset entries inside the allocation table are stored big endian
805	* we need to convert them into host endian.
806	*/
807	pImage->pBlockAllocationTable = (uint32_t )RTMemAllocZ(pImage->cBlockAllocationTableEntries sizeof(uint32_t));
808	if (!pImage->pBlockAllocationTable)
809	{
810	RTMemFree(pBlockAllocationTable);
811	return VERR_NO_MEMORY;
812	}
813
814	for (i = 0; i < pImage->cBlockAllocationTableEntries; i++)
815	pImage->pBlockAllocationTable[i] = RT_BE2H_U32(pBlockAllocationTable[i]);
816
817	RTMemFree(pBlockAllocationTable);
818
819	if (pImage->uImageFlags & VD_IMAGE_FLAGS_DIFF)
820	memcpy(pImage->ParentUuid.au8, vhdDynamicDiskHeader.ParentUuid, sizeof(pImage->ParentUuid));
821
822	return rc;
823	}
824
825	static int vhdOpenImage(PVHDIMAGE pImage, unsigned uOpenFlags)
826	{
827	uint64_t FileSize;
828	VHDFooter vhdFooter;
829
830	pImage->uOpenFlags = uOpenFlags;
831
832	pImage->pIfError = VDIfErrorGet(pImage->pVDIfsDisk);
833	pImage->pIfIo = VDIfIoIntGet(pImage->pVDIfsImage);
834	AssertPtrReturn(pImage->pIfIo, VERR_INVALID_PARAMETER);
835
836	/*
837	* Open the image.
838	*/
839	int rc = vdIfIoIntFileOpen(pImage->pIfIo, pImage->pszFilename,
840	VDOpenFlagsToFileOpenFlags(uOpenFlags,
841	false /* fCreate */),
842	&pImage->pStorage);
843	if (RT_FAILURE(rc))
844	{
845	/* Do NOT signal an appropriate error here, as the VD layer has the
846	* choice of retrying the open if it failed. */
847	return rc;
848	}
849
850	rc = vdIfIoIntFileGetSize(pImage->pIfIo, pImage->pStorage, &FileSize);
851	pImage->uCurrentEndOfFile = FileSize - sizeof(VHDFooter);
852
853	rc = vdIfIoIntFileReadSync(pImage->pIfIo, pImage->pStorage, pImage->uCurrentEndOfFile,
854	&vhdFooter, sizeof(VHDFooter));
855	if (RT_SUCCESS(rc))
856	{
857	if (memcmp(vhdFooter.Cookie, VHD_FOOTER_COOKIE, VHD_FOOTER_COOKIE_SIZE) != 0)
858	{
859	/*
860	* There is also a backup header at the beginning in case the image got corrupted.
861	* Such corrupted images are detected here to let the open handler repair it later.
862	*/
863	rc = vdIfIoIntFileReadSync(pImage->pIfIo, pImage->pStorage, 0,
864	&vhdFooter, sizeof(VHDFooter));
865	if (RT_SUCCESS(rc))
866	{
867	if (memcmp(vhdFooter.Cookie, VHD_FOOTER_COOKIE, VHD_FOOTER_COOKIE_SIZE) != 0)
868	rc = VERR_VD_VHD_INVALID_HEADER;
869	else
870	rc = VERR_VD_IMAGE_CORRUPTED;
871	}
872	}
873	}
874
875	if (RT_FAILURE(rc))
876	{
877	vhdFreeImage(pImage, false);
878	return rc;
879	}
880
881	switch (RT_BE2H_U32(vhdFooter.DiskType))
882	{
883	case VHD_FOOTER_DISK_TYPE_FIXED:
884	pImage->uImageFlags \|= VD_IMAGE_FLAGS_FIXED;
885	break;
886	case VHD_FOOTER_DISK_TYPE_DYNAMIC:
887	pImage->uImageFlags &= ~VD_IMAGE_FLAGS_FIXED;
888	break;
889	case VHD_FOOTER_DISK_TYPE_DIFFERENCING:
890	pImage->uImageFlags \|= VD_IMAGE_FLAGS_DIFF;
891	pImage->uImageFlags &= ~VD_IMAGE_FLAGS_FIXED;
892	break;
893	default:
894	vhdFreeImage(pImage, false);
895	return VERR_NOT_IMPLEMENTED;
896	}
897
898	pImage->cbSize = RT_BE2H_U64(vhdFooter.CurSize);
899	pImage->LCHSGeometry.cCylinders = 0;
900	pImage->LCHSGeometry.cHeads = 0;
901	pImage->LCHSGeometry.cSectors = 0;
902	pImage->PCHSGeometry.cCylinders = RT_BE2H_U16(vhdFooter.DiskGeometryCylinder);
903	pImage->PCHSGeometry.cHeads = vhdFooter.DiskGeometryHeads;
904	pImage->PCHSGeometry.cSectors = vhdFooter.DiskGeometrySectors;
905
906	/*
907	* Copy of the disk footer.
908	* If we allocate new blocks in differencing disks on write access
909	* the footer is overwritten. We need to write it at the end of the file.
910	*/
911	memcpy(&pImage->vhdFooterCopy, &vhdFooter, sizeof(VHDFooter));
912
913	/*
914	* Is there a better way?
915	*/
916	memcpy(&pImage->ImageUuid, &vhdFooter.UniqueID, 16);
917
918	pImage->u64DataOffset = RT_BE2H_U64(vhdFooter.DataOffset);
919	LogFlowFunc(("DataOffset=%llu\n", pImage->u64DataOffset));
920
921	if (!(pImage->uImageFlags & VD_IMAGE_FLAGS_FIXED))
922	rc = vhdLoadDynamicDisk(pImage, pImage->u64DataOffset);
923
924	if (RT_SUCCESS(rc))
925	{
926	PVDREGIONDESC pRegion = &pImage->RegionList.aRegions[0];
927	pImage->RegionList.fFlags = 0;
928	pImage->RegionList.cRegions = 1;
929
930	pRegion->offRegion = 0; /* Disk start. */
931	pRegion->cbBlock = 512;
932	pRegion->enmDataForm = VDREGIONDATAFORM_RAW;
933	pRegion->enmMetadataForm = VDREGIONMETADATAFORM_NONE;
934	pRegion->cbData = 512;
935	pRegion->cbMetadata = 0;
936	pRegion->cRegionBlocksOrBytes = pImage->cbSize;
937	}
938	else
939	vhdFreeImage(pImage, false);
940	return rc;
941	}
942
943	/**
944	* Internal: Checks if a sector in the block bitmap is set
945	*/
946	DECLINLINE(bool) vhdBlockBitmapSectorContainsData(PVHDIMAGE pImage, uint32_t cBlockBitmapEntry)
947	{
948	uint32_t iBitmap = (cBlockBitmapEntry / 8); /* Byte in the block bitmap. */
949
950	/*
951	* The index of the bit in the byte of the data block bitmap.
952	* The most significant bit stands for a lower sector number.
953	*/
954	uint8_t iBitInByte = (8-1) - (cBlockBitmapEntry % 8);
955	uint8_t *puBitmap = pImage->pu8Bitmap + iBitmap;
956
957	AssertMsg(puBitmap < (pImage->pu8Bitmap + pImage->cbDataBlockBitmap),
958	("VHD: Current bitmap position exceeds maximum size of the bitmap\n"));
959
960	return ((*puBitmap) & RT_BIT(iBitInByte)) != 0;
961	}
962
963	/**
964	* Internal: Sets the given sector in the sector bitmap.
965	*/
966	DECLINLINE(bool) vhdBlockBitmapSectorSet(PVHDIMAGE pImage, uint8_t *pu8Bitmap, uint32_t cBlockBitmapEntry)
967	{
968	RT_NOREF1(pImage);
969	uint32_t iBitmap = (cBlockBitmapEntry / 8); /* Byte in the block bitmap. */
970
971	/*
972	* The index of the bit in the byte of the data block bitmap.
973	* The most significant bit stands for a lower sector number.
974	*/
975	uint8_t iBitInByte = (8-1) - (cBlockBitmapEntry % 8);
976	uint8_t *puBitmap = pu8Bitmap + iBitmap;
977
978	AssertMsg(puBitmap < (pu8Bitmap + pImage->cbDataBlockBitmap),
979	("VHD: Current bitmap position exceeds maximum size of the bitmap\n"));
980
981	bool fClear = ((*puBitmap) & RT_BIT(iBitInByte)) == 0;
982	*puBitmap \|= RT_BIT(iBitInByte);
983	return fClear;
984	}
985
986	/**
987	* Internal: Derive drive geometry from its size.
988	*/
989	static void vhdSetDiskGeometry(PVHDIMAGE pImage, uint64_t cbSize)
990	{
991	uint64_t u64TotalSectors = cbSize / VHD_SECTOR_SIZE;
992	uint32_t u32CylinderTimesHeads, u32Heads, u32SectorsPerTrack;
993
994	if (u64TotalSectors > 65535 * 16 * 255)
995	{
996	/* ATA disks limited to 127 GB. */
997	u64TotalSectors = 65535 * 16 * 255;
998	}
999
1000	if (u64TotalSectors >= 65535 * 16 * 63)
1001	{
1002	u32SectorsPerTrack = 255;
1003	u32Heads = 16;
1004	u32CylinderTimesHeads = u64TotalSectors / u32SectorsPerTrack;
1005	}
1006	else
1007	{
1008	u32SectorsPerTrack = 17;
1009	u32CylinderTimesHeads = u64TotalSectors / u32SectorsPerTrack;
1010
1011	u32Heads = (u32CylinderTimesHeads + 1023) / 1024;
1012
1013	if (u32Heads < 4)
1014	{
1015	u32Heads = 4;
1016	}
1017	if (u32CylinderTimesHeads >= (u32Heads * 1024) \|\| u32Heads > 16)
1018	{
1019	u32SectorsPerTrack = 31;
1020	u32Heads = 16;
1021	u32CylinderTimesHeads = u64TotalSectors / u32SectorsPerTrack;
1022	}
1023	if (u32CylinderTimesHeads >= (u32Heads * 1024))
1024	{
1025	u32SectorsPerTrack = 63;
1026	u32Heads = 16;
1027	u32CylinderTimesHeads = u64TotalSectors / u32SectorsPerTrack;
1028	}
1029	}
1030	pImage->PCHSGeometry.cCylinders = u32CylinderTimesHeads / u32Heads;
1031	pImage->PCHSGeometry.cHeads = u32Heads;
1032	pImage->PCHSGeometry.cSectors = u32SectorsPerTrack;
1033	pImage->LCHSGeometry.cCylinders = 0;
1034	pImage->LCHSGeometry.cHeads = 0;
1035	pImage->LCHSGeometry.cSectors = 0;
1036	}
1037
1038
1039	static uint32_t vhdAllocateParentLocators(PVHDIMAGE pImage, VHDDynamicDiskHeader *pDDH, uint64_t u64Offset)
1040	{
1041	RT_NOREF1(pImage);
1042	PVHDPLE pLocator = pDDH->ParentLocatorEntry;
1043
1044	/*
1045	* The VHD spec states that the DataSpace field holds the number of sectors
1046	* required to store the parent locator path.
1047	* As it turned out VPC and Hyper-V store the amount of bytes reserved for the
1048	* path and not the number of sectors.
1049	*/
1050
1051	/* Unicode absolute Windows path. */
1052	pLocator->u32Code = RT_H2BE_U32(VHD_PLATFORM_CODE_W2KU);
1053	pLocator->u32DataSpace = RT_H2BE_U32(VHD_ABSOLUTE_MAX_PATH * sizeof(RTUTF16));
1054	pLocator->u64DataOffset = RT_H2BE_U64(u64Offset);
1055	pLocator++;
1056	u64Offset += VHD_ABSOLUTE_MAX_PATH * sizeof(RTUTF16);
1057	/* Unicode relative Windows path. */
1058	pLocator->u32Code = RT_H2BE_U32(VHD_PLATFORM_CODE_W2RU);
1059	pLocator->u32DataSpace = RT_H2BE_U32(VHD_RELATIVE_MAX_PATH * sizeof(RTUTF16));
1060	pLocator->u64DataOffset = RT_H2BE_U64(u64Offset);
1061	u64Offset += VHD_RELATIVE_MAX_PATH * sizeof(RTUTF16);
1062	return u64Offset;
1063	}
1064
1065	/**
1066	* Internal: Additional code for dynamic VHD image creation.
1067	*/
1068	static int vhdCreateDynamicImage(PVHDIMAGE pImage, uint64_t cbSize)
1069	{
1070	int rc;
1071	VHDDynamicDiskHeader DynamicDiskHeader;
1072	uint32_t u32BlockAllocationTableSectors;
1073	void *pvTmp = NULL;
1074
1075	memset(&DynamicDiskHeader, 0, sizeof(DynamicDiskHeader));
1076
1077	pImage->u64DataOffset = sizeof(VHDFooter);
1078	pImage->cbDataBlock = VHD_BLOCK_SIZE; /* 2 MB */
1079	pImage->cSectorsPerDataBlock = pImage->cbDataBlock / VHD_SECTOR_SIZE;
1080	pImage->cbDataBlockBitmap = pImage->cSectorsPerDataBlock / 8;
1081	pImage->cDataBlockBitmapSectors = pImage->cbDataBlockBitmap / VHD_SECTOR_SIZE;
1082	/* Align to sector boundary */
1083	if (pImage->cbDataBlockBitmap % VHD_SECTOR_SIZE > 0)
1084	pImage->cDataBlockBitmapSectors++;
1085	pImage->pu8Bitmap = vhdBlockBitmapAllocate(pImage);
1086	if (!pImage->pu8Bitmap)
1087	return vdIfError(pImage->pIfError, VERR_NO_MEMORY, RT_SRC_POS, N_("VHD: cannot allocate memory for bitmap storage"));
1088
1089	/* Initialize BAT. */
1090	pImage->uBlockAllocationTableOffset = (uint64_t)sizeof(VHDFooter) + sizeof(VHDDynamicDiskHeader);
1091	pImage->cBlockAllocationTableEntries = (uint32_t)((cbSize + pImage->cbDataBlock - 1) / pImage->cbDataBlock); /* Align table to the block size. */
1092	u32BlockAllocationTableSectors = (pImage->cBlockAllocationTableEntries * sizeof(uint32_t) + VHD_SECTOR_SIZE - 1) / VHD_SECTOR_SIZE;
1093	pImage->pBlockAllocationTable = (uint32_t )RTMemAllocZ(pImage->cBlockAllocationTableEntries sizeof(uint32_t));
1094	if (!pImage->pBlockAllocationTable)
1095	return vdIfError(pImage->pIfError, VERR_NO_MEMORY, RT_SRC_POS, N_("VHD: cannot allocate memory for BAT"));
1096
1097	for (unsigned i = 0; i < pImage->cBlockAllocationTableEntries; i++)
1098	{
1099	pImage->pBlockAllocationTable[i] = 0xFFFFFFFF; /* It is actually big endian. */
1100	}
1101
1102	/* Round up to the sector size. */
1103	if (pImage->uImageFlags & VD_IMAGE_FLAGS_DIFF) /* fix hyper-v unreadable error */
1104	pImage->uCurrentEndOfFile = vhdAllocateParentLocators(pImage, &DynamicDiskHeader,
1105	pImage->uBlockAllocationTableOffset + u32BlockAllocationTableSectors * VHD_SECTOR_SIZE);
1106	else
1107	pImage->uCurrentEndOfFile = pImage->uBlockAllocationTableOffset + u32BlockAllocationTableSectors * VHD_SECTOR_SIZE;
1108
1109	/* Set dynamic image size. */
1110	pvTmp = RTMemTmpAllocZ(pImage->uCurrentEndOfFile + sizeof(VHDFooter));
1111	if (!pvTmp)
1112	return vdIfError(pImage->pIfError, VERR_NO_MEMORY, RT_SRC_POS, N_("VHD: cannot set the file size for '%s'"), pImage->pszFilename);
1113
1114	rc = vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage, 0, pvTmp,
1115	pImage->uCurrentEndOfFile + sizeof(VHDFooter));
1116	if (RT_FAILURE(rc))
1117	{
1118	RTMemTmpFree(pvTmp);
1119	return vdIfError(pImage->pIfError, rc, RT_SRC_POS, N_("VHD: cannot set the file size for '%s'"), pImage->pszFilename);
1120	}
1121
1122	RTMemTmpFree(pvTmp);
1123
1124	/* Initialize and write the dynamic disk header. */
1125	memcpy(DynamicDiskHeader.Cookie, VHD_DYNAMIC_DISK_HEADER_COOKIE, sizeof(DynamicDiskHeader.Cookie));
1126	DynamicDiskHeader.DataOffset = UINT64_C(0xFFFFFFFFFFFFFFFF); /* Initially the disk has no data. */
1127	DynamicDiskHeader.TableOffset = RT_H2BE_U64(pImage->uBlockAllocationTableOffset);
1128	DynamicDiskHeader.HeaderVersion = RT_H2BE_U32(VHD_DYNAMIC_DISK_HEADER_VERSION);
1129	DynamicDiskHeader.BlockSize = RT_H2BE_U32(pImage->cbDataBlock);
1130	DynamicDiskHeader.MaxTableEntries = RT_H2BE_U32(pImage->cBlockAllocationTableEntries);
1131	/* Compute and update checksum. */
1132	DynamicDiskHeader.Checksum = 0;
1133	DynamicDiskHeader.Checksum = RT_H2BE_U32(vhdChecksum(&DynamicDiskHeader, sizeof(DynamicDiskHeader)));
1134
1135	rc = vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage, sizeof(VHDFooter),
1136	&DynamicDiskHeader, sizeof(DynamicDiskHeader));
1137	if (RT_FAILURE(rc))
1138	return vdIfError(pImage->pIfError, rc, RT_SRC_POS, N_("VHD: cannot write dynamic disk header to image '%s'"), pImage->pszFilename);
1139
1140	/* Write BAT. */
1141	rc = vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage, pImage->uBlockAllocationTableOffset,
1142	pImage->pBlockAllocationTable,
1143	pImage->cBlockAllocationTableEntries * sizeof(uint32_t));
1144	if (RT_FAILURE(rc))
1145	return vdIfError(pImage->pIfError, rc, RT_SRC_POS, N_("VHD: cannot write BAT to image '%s'"), pImage->pszFilename);
1146
1147	return rc;
1148	}
1149
1150	/**
1151	* Internal: The actual code for VHD image creation, both fixed and dynamic.
1152	*/
1153	static int vhdCreateImage(PVHDIMAGE pImage, uint64_t cbSize,
1154	unsigned uImageFlags, const char *pszComment,
1155	PCVDGEOMETRY pPCHSGeometry,
1156	PCVDGEOMETRY pLCHSGeometry, PCRTUUID pUuid,
1157	unsigned uOpenFlags,
1158	PVDINTERFACEPROGRESS pIfProgress,
1159	unsigned uPercentStart, unsigned uPercentSpan)
1160	{
1161	RT_NOREF3(pszComment, pPCHSGeometry, pLCHSGeometry);
1162	VHDFooter Footer;
1163	RTTIMESPEC now;
1164
1165	pImage->uOpenFlags = uOpenFlags;
1166	pImage->uImageFlags = uImageFlags;
1167	pImage->pIfError = VDIfErrorGet(pImage->pVDIfsDisk);
1168
1169	int rc = vdIfIoIntFileOpen(pImage->pIfIo, pImage->pszFilename,
1170	VDOpenFlagsToFileOpenFlags(uOpenFlags & ~VD_OPEN_FLAGS_READONLY,
1171	true /* fCreate */),
1172	&pImage->pStorage);
1173	if (RT_SUCCESS(rc))
1174	{
1175	pImage->cbSize = cbSize;
1176	pImage->ImageUuid = *pUuid;
1177	RTUuidClear(&pImage->ParentUuid);
1178	vhdSetDiskGeometry(pImage, cbSize);
1179
1180	/* Initialize the footer. */
1181	memset(&Footer, 0, sizeof(Footer));
1182	memcpy(Footer.Cookie, VHD_FOOTER_COOKIE, sizeof(Footer.Cookie));
1183	Footer.Features = RT_H2BE_U32(0x2);
1184	Footer.Version = RT_H2BE_U32(VHD_FOOTER_FILE_FORMAT_VERSION);
1185	Footer.Timestamp = RT_H2BE_U32(vhdRtTime2VhdTime(RTTimeNow(&now)));
1186	memcpy(Footer.CreatorApp, "vbox", sizeof(Footer.CreatorApp));
1187	Footer.CreatorVer = RT_H2BE_U32(VBOX_VERSION);
1188	#ifdef RT_OS_DARWIN
1189	Footer.CreatorOS = RT_H2BE_U32(0x4D616320); /* "Mac " */
1190	#else /* Virtual PC supports only two platforms atm, so everything else will be Wi2k. */
1191	Footer.CreatorOS = RT_H2BE_U32(0x5769326B); /* "Wi2k" */
1192	#endif
1193	Footer.OrigSize = RT_H2BE_U64(cbSize);
1194	Footer.CurSize = Footer.OrigSize;
1195	Footer.DiskGeometryCylinder = RT_H2BE_U16(pImage->PCHSGeometry.cCylinders);
1196	Footer.DiskGeometryHeads = pImage->PCHSGeometry.cHeads;
1197	Footer.DiskGeometrySectors = pImage->PCHSGeometry.cSectors;
1198	memcpy(Footer.UniqueID, pImage->ImageUuid.au8, sizeof(Footer.UniqueID));
1199	Footer.SavedState = 0;
1200
1201	if (uImageFlags & VD_IMAGE_FLAGS_FIXED)
1202	{
1203	Footer.DiskType = RT_H2BE_U32(VHD_FOOTER_DISK_TYPE_FIXED);
1204	/*
1205	* Initialize fixed image.
1206	* "The size of the entire file is the size of the hard disk in
1207	* the guest operating system plus the size of the footer."
1208	*/
1209	pImage->u64DataOffset = VHD_FOOTER_DATA_OFFSET_FIXED;
1210	pImage->uCurrentEndOfFile = cbSize;
1211	rc = vdIfIoIntFileSetAllocationSize(pImage->pIfIo, pImage->pStorage, pImage->uCurrentEndOfFile + sizeof(VHDFooter),
1212	0 /* fFlags */, pIfProgress,
1213	uPercentStart, uPercentSpan);
1214	if (RT_FAILURE(rc))
1215	rc = vdIfError(pImage->pIfError, rc, RT_SRC_POS, N_("VHD: cannot set the file size for '%s'"), pImage->pszFilename);
1216	}
1217	else
1218	{
1219	/*
1220	* Initialize dynamic image.
1221	*
1222	* The overall structure of dynamic disk is:
1223	*
1224	* [Copy of hard disk footer (512 bytes)]
1225	* [Dynamic disk header (1024 bytes)]
1226	* [BAT (Block Allocation Table)]
1227	* [Parent Locators]
1228	* [Data block 1]
1229	* [Data block 2]
1230	* ...
1231	* [Data block N]
1232	* [Hard disk footer (512 bytes)]
1233	*/
1234	Footer.DiskType = (uImageFlags & VD_IMAGE_FLAGS_DIFF)
1235	? RT_H2BE_U32(VHD_FOOTER_DISK_TYPE_DIFFERENCING)
1236	: RT_H2BE_U32(VHD_FOOTER_DISK_TYPE_DYNAMIC);
1237	/* We are half way thorough with creation of image, let the caller know. */
1238	vdIfProgress(pIfProgress, (uPercentStart + uPercentSpan) / 2);
1239
1240	rc = vhdCreateDynamicImage(pImage, cbSize);
1241	}
1242
1243	if (RT_SUCCESS(rc))
1244	{
1245	/* Compute and update the footer checksum. */
1246	Footer.DataOffset = RT_H2BE_U64(pImage->u64DataOffset);
1247	Footer.Checksum = 0;
1248	Footer.Checksum = RT_H2BE_U32(vhdChecksum(&Footer, sizeof(Footer)));
1249
1250	pImage->vhdFooterCopy = Footer;
1251
1252	/* Store the footer */
1253	rc = vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage, pImage->uCurrentEndOfFile,
1254	&Footer, sizeof(Footer));
1255	if (RT_SUCCESS(rc))
1256	{
1257	/* Dynamic images contain a copy of the footer at the very beginning of the file. */
1258	if (!(uImageFlags & VD_IMAGE_FLAGS_FIXED))
1259	{
1260	/* Write the copy of the footer. */
1261	rc = vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage, 0, &Footer, sizeof(Footer));
1262	if (RT_FAILURE(rc))
1263	rc = vdIfError(pImage->pIfError, rc, RT_SRC_POS, N_("VHD: cannot write a copy of footer to image '%s'"), pImage->pszFilename);
1264	}
1265	}
1266	else
1267	rc = vdIfError(pImage->pIfError, rc, RT_SRC_POS, N_("VHD: cannot write footer to image '%s'"), pImage->pszFilename);
1268	}
1269	}
1270	else
1271	rc = vdIfError(pImage->pIfError, rc, RT_SRC_POS, N_("VHD: cannot create image '%s'"), pImage->pszFilename);
1272
1273	if (RT_SUCCESS(rc))
1274	vdIfProgress(pIfProgress, uPercentStart + uPercentSpan);
1275
1276	if (RT_SUCCESS(rc))
1277	{
1278	PVDREGIONDESC pRegion = &pImage->RegionList.aRegions[0];
1279	pImage->RegionList.fFlags = 0;
1280	pImage->RegionList.cRegions = 1;
1281
1282	pRegion->offRegion = 0; /* Disk start. */
1283	pRegion->cbBlock = 512;
1284	pRegion->enmDataForm = VDREGIONDATAFORM_RAW;
1285	pRegion->enmMetadataForm = VDREGIONMETADATAFORM_NONE;
1286	pRegion->cbData = 512;
1287	pRegion->cbMetadata = 0;
1288	pRegion->cRegionBlocksOrBytes = pImage->cbSize;
1289	}
1290	else
1291	vhdFreeImage(pImage, rc != VERR_ALREADY_EXISTS);
1292	return rc;
1293	}
1294
1295
1296	/** @interface_method_impl{VDIMAGEBACKEND,pfnProbe} */
1297	static DECLCALLBACK(int) vhdProbe(const char *pszFilename, PVDINTERFACE pVDIfsDisk,
1298	PVDINTERFACE pVDIfsImage, VDTYPE enmDesiredType, VDTYPE *penmType)
1299	{
1300	RT_NOREF(pVDIfsDisk, enmDesiredType);
1301	LogFlowFunc(("pszFilename=\"%s\" pVDIfsDisk=%#p pVDIfsImage=%#p\n", pszFilename, pVDIfsDisk, pVDIfsImage));
1302	PVDIOSTORAGE pStorage;
1303	PVDINTERFACEIOINT pIfIo = VDIfIoIntGet(pVDIfsImage);
1304	AssertPtrReturn(pIfIo, VERR_INVALID_PARAMETER);
1305
1306	int rc = vdIfIoIntFileOpen(pIfIo, pszFilename,
1307	VDOpenFlagsToFileOpenFlags(VD_OPEN_FLAGS_READONLY,
1308	false /* fCreate */),
1309	&pStorage);
1310	if (RT_SUCCESS(rc))
1311	{
1312	uint64_t cbFile;
1313
1314	rc = vdIfIoIntFileGetSize(pIfIo, pStorage, &cbFile);
1315	if ( RT_SUCCESS(rc)
1316	&& cbFile >= sizeof(VHDFooter))
1317	{
1318	VHDFooter vhdFooter;
1319
1320	rc = vdIfIoIntFileReadSync(pIfIo, pStorage, cbFile - sizeof(VHDFooter),
1321	&vhdFooter, sizeof(VHDFooter));
1322	if (RT_SUCCESS(rc))
1323	{
1324	if (memcmp(vhdFooter.Cookie, VHD_FOOTER_COOKIE, VHD_FOOTER_COOKIE_SIZE) != 0)
1325	{
1326	/*
1327	* There is also a backup header at the beginning in case the image got corrupted.
1328	* Such corrupted images are detected here to let the open handler repair it later.
1329	*/
1330	rc = vdIfIoIntFileReadSync(pIfIo, pStorage, 0, &vhdFooter, sizeof(VHDFooter));
1331	if ( RT_FAILURE(rc)
1332	\|\| (memcmp(vhdFooter.Cookie, VHD_FOOTER_COOKIE, VHD_FOOTER_COOKIE_SIZE) != 0))
1333	rc = VERR_VD_VHD_INVALID_HEADER;
1334	}
1335
1336	if (RT_SUCCESS(rc))
1337	*penmType = VDTYPE_HDD;
1338	}
1339	else
1340	rc = VERR_VD_VHD_INVALID_HEADER;
1341	}
1342	else if (RT_SUCCESS(rc))
1343	rc = VERR_VD_VHD_INVALID_HEADER;
1344
1345	vdIfIoIntFileClose(pIfIo, pStorage);
1346	}
1347
1348	LogFlowFunc(("returns %Rrc\n", rc));
1349	return rc;
1350	}
1351
1352	/** @interface_method_impl{VDIMAGEBACKEND,pfnOpen} */
1353	static DECLCALLBACK(int) vhdOpen(const char *pszFilename, unsigned uOpenFlags,
1354	PVDINTERFACE pVDIfsDisk, PVDINTERFACE pVDIfsImage,
1355	VDTYPE enmType, void **ppBackendData)
1356	{
1357	RT_NOREF1(enmType); /*< @todo r=klaus make use of the type info. /
1358
1359	LogFlowFunc(("pszFilename=\"%s\" uOpenFlags=%#x pVDIfsDisk=%#p pVDIfsImage=%#p enmType=%u ppBackendData=%#p\n",
1360	pszFilename, uOpenFlags, pVDIfsDisk, pVDIfsImage, enmType, ppBackendData));
1361	int rc = VINF_SUCCESS;
1362
1363	/* Check open flags. All valid flags are supported. */
1364	AssertReturn(!(uOpenFlags & ~VD_OPEN_FLAGS_MASK), VERR_INVALID_PARAMETER);
1365	AssertPtrReturn(pszFilename, VERR_INVALID_POINTER);
1366	AssertReturn(*pszFilename != '\0', VERR_INVALID_PARAMETER);
1367
1368
1369	PVHDIMAGE pImage = (PVHDIMAGE)RTMemAllocZ(RT_UOFFSETOF(VHDIMAGE, RegionList.aRegions[1]));
1370	if (RT_LIKELY(pImage))
1371	{
1372	pImage->pszFilename = pszFilename;
1373	pImage->pStorage = NULL;
1374	pImage->pVDIfsDisk = pVDIfsDisk;
1375	pImage->pVDIfsImage = pVDIfsImage;
1376
1377	rc = vhdOpenImage(pImage, uOpenFlags);
1378	if (RT_SUCCESS(rc))
1379	*ppBackendData = pImage;
1380	else
1381	RTMemFree(pImage);
1382	}
1383	else
1384	rc = VERR_NO_MEMORY;
1385
1386	LogFlowFunc(("returns %Rrc (pBackendData=%#p)\n", rc, *ppBackendData));
1387	return rc;
1388	}
1389
1390	/** @interface_method_impl{VDIMAGEBACKEND,pfnCreate} */
1391	static DECLCALLBACK(int) vhdCreate(const char *pszFilename, uint64_t cbSize,
1392	unsigned uImageFlags, const char *pszComment,
1393	PCVDGEOMETRY pPCHSGeometry, PCVDGEOMETRY pLCHSGeometry,
1394	PCRTUUID pUuid, unsigned uOpenFlags,
1395	unsigned uPercentStart, unsigned uPercentSpan,
1396	PVDINTERFACE pVDIfsDisk, PVDINTERFACE pVDIfsImage,
1397	PVDINTERFACE pVDIfsOperation, VDTYPE enmType,
1398	void **ppBackendData)
1399	{
1400	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",
1401	pszFilename, cbSize, uImageFlags, pszComment, pPCHSGeometry, pLCHSGeometry, pUuid, uOpenFlags, uPercentStart, uPercentSpan, pVDIfsDisk, pVDIfsImage, pVDIfsOperation, enmType, ppBackendData));
1402	int rc;
1403	PVDINTERFACEPROGRESS pIfProgress = VDIfProgressGet(pVDIfsOperation);
1404
1405	/* Check the VD container type. */
1406	if (enmType != VDTYPE_HDD)
1407	return VERR_VD_INVALID_TYPE;
1408
1409	/* Check open flags. All valid flags are supported. */
1410	AssertReturn(!(uOpenFlags & ~VD_OPEN_FLAGS_MASK), VERR_INVALID_PARAMETER);
1411	AssertPtrReturn(pszFilename, VERR_INVALID_POINTER);
1412	AssertReturn(*pszFilename != '\0', VERR_INVALID_PARAMETER);
1413	AssertPtrReturn(pPCHSGeometry, VERR_INVALID_POINTER);
1414	AssertPtrReturn(pLCHSGeometry, VERR_INVALID_POINTER);
1415	/** @todo Check the values of other params */
1416
1417	PVHDIMAGE pImage = (PVHDIMAGE)RTMemAllocZ(RT_UOFFSETOF(VHDIMAGE, RegionList.aRegions[1]));
1418	if (RT_LIKELY(pImage))
1419	{
1420	pImage->pszFilename = pszFilename;
1421	pImage->pStorage = NULL;
1422	pImage->pVDIfsDisk = pVDIfsDisk;
1423	pImage->pVDIfsImage = pVDIfsImage;
1424
1425	/* Get I/O interface. */
1426	pImage->pIfIo = VDIfIoIntGet(pImage->pVDIfsImage);
1427	if (RT_LIKELY(RT_VALID_PTR(pImage->pIfIo)))
1428	{
1429	rc = vhdCreateImage(pImage, cbSize, uImageFlags, pszComment,
1430	pPCHSGeometry, pLCHSGeometry, pUuid, uOpenFlags,
1431	pIfProgress, uPercentStart, uPercentSpan);
1432	if (RT_SUCCESS(rc))
1433	{
1434	/* So far the image is opened in read/write mode. Make sure the
1435	* image is opened in read-only mode if the caller requested that. */
1436	if (uOpenFlags & VD_OPEN_FLAGS_READONLY)
1437	{
1438	vhdFreeImage(pImage, false);
1439	rc = vhdOpenImage(pImage, uOpenFlags);
1440	}
1441
1442	if (RT_SUCCESS(rc))
1443	*ppBackendData = pImage;
1444	}
1445	}
1446	else
1447	rc = VERR_INVALID_PARAMETER;
1448
1449	if (RT_FAILURE(rc))
1450	RTMemFree(pImage);
1451	}
1452	else
1453	rc = VERR_NO_MEMORY;
1454
1455	LogFlowFunc(("returns %Rrc\n", rc));
1456	return rc;
1457	}
1458
1459	/** @interface_method_impl{VDIMAGEBACKEND,pfnRename} */
1460	static DECLCALLBACK(int) vhdRename(void pBackendData, const char pszFilename)
1461	{
1462	LogFlowFunc(("pBackendData=%#p pszFilename=%#p\n", pBackendData, pszFilename));
1463	int rc = VINF_SUCCESS;
1464	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
1465
1466	/* Check arguments. */
1467	AssertReturn((pImage && pszFilename && *pszFilename), VERR_INVALID_PARAMETER);
1468
1469	/* Close the image. */
1470	rc = vhdFreeImage(pImage, false);
1471	if (RT_SUCCESS(rc))
1472	{
1473	/* Rename the file. */
1474	rc = vdIfIoIntFileMove(pImage->pIfIo, pImage->pszFilename, pszFilename, 0);
1475	if (RT_SUCCESS(rc))
1476	{
1477	/* Update pImage with the new information. */
1478	pImage->pszFilename = pszFilename;
1479
1480	/* Open the old file with new name. */
1481	rc = vhdOpenImage(pImage, pImage->uOpenFlags);
1482	}
1483	else
1484	{
1485	/* The move failed, try to reopen the original image. */
1486	int rc2 = vhdOpenImage(pImage, pImage->uOpenFlags);
1487	if (RT_FAILURE(rc2))
1488	rc = rc2;
1489	}
1490	}
1491
1492	LogFlowFunc(("returns %Rrc\n", rc));
1493	return rc;
1494	}
1495
1496	/** @interface_method_impl{VDIMAGEBACKEND,pfnClose} */
1497	static DECLCALLBACK(int) vhdClose(void *pBackendData, bool fDelete)
1498	{
1499	LogFlowFunc(("pBackendData=%#p fDelete=%d\n", pBackendData, fDelete));
1500	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
1501
1502	int rc = vhdFreeImage(pImage, fDelete);
1503	RTMemFree(pImage);
1504
1505	LogFlowFunc(("returns %Rrc\n", rc));
1506	return rc;
1507	}
1508
1509	/** @interface_method_impl{VDIMAGEBACKEND,pfnRead} */
1510	static DECLCALLBACK(int) vhdRead(void *pBackendData, uint64_t uOffset, size_t cbToRead,
1511	PVDIOCTX pIoCtx, size_t *pcbActuallyRead)
1512	{
1513	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
1514	int rc = VINF_SUCCESS;
1515
1516	LogFlowFunc(("pBackendData=%p uOffset=%#llx pIoCtx=%#p cbToRead=%u pcbActuallyRead=%p\n",
1517	pBackendData, uOffset, pIoCtx, cbToRead, pcbActuallyRead));
1518
1519	AssertPtr(pImage);
1520	Assert(uOffset % 512 == 0);
1521	Assert(cbToRead % 512 == 0);
1522	AssertPtrReturn(pIoCtx, VERR_INVALID_POINTER);
1523	AssertReturn(cbToRead, VERR_INVALID_PARAMETER);
1524	AssertReturn(uOffset + cbToRead <= pImage->cbSize, VERR_INVALID_PARAMETER);
1525
1526	/*
1527	* If we have a dynamic disk image, we need to find the data block and sector to read.
1528	*/
1529	if (pImage->pBlockAllocationTable)
1530	{
1531	/*
1532	* Get the data block first.
1533	*/
1534	uint32_t cBlockAllocationTableEntry = (uOffset / VHD_SECTOR_SIZE) / pImage->cSectorsPerDataBlock;
1535	uint32_t cBATEntryIndex = (uOffset / VHD_SECTOR_SIZE) % pImage->cSectorsPerDataBlock;
1536	uint64_t uVhdOffset;
1537
1538	LogFlowFunc(("cBlockAllocationTableEntry=%u cBatEntryIndex=%u\n", cBlockAllocationTableEntry, cBATEntryIndex));
1539	LogFlowFunc(("BlockAllocationEntry=%u\n", pImage->pBlockAllocationTable[cBlockAllocationTableEntry]));
1540
1541	/*
1542	* Clip read range to remain in this data block.
1543	*/
1544	cbToRead = RT_MIN(cbToRead, (pImage->cbDataBlock - (cBATEntryIndex * VHD_SECTOR_SIZE)));
1545
1546	/*
1547	* If the block is not allocated the content of the entry is ~0
1548	*/
1549	if (pImage->pBlockAllocationTable[cBlockAllocationTableEntry] == ~0U)
1550	rc = VERR_VD_BLOCK_FREE;
1551	else
1552	{
1553	uVhdOffset = ((uint64_t)pImage->pBlockAllocationTable[cBlockAllocationTableEntry] + pImage->cDataBlockBitmapSectors + cBATEntryIndex) * VHD_SECTOR_SIZE;
1554	LogFlowFunc(("uVhdOffset=%llu cbToRead=%u\n", uVhdOffset, cbToRead));
1555
1556	/* Read in the block's bitmap. */
1557	PVDMETAXFER pMetaXfer;
1558	rc = vdIfIoIntFileReadMeta(pImage->pIfIo, pImage->pStorage,
1559	((uint64_t)pImage->pBlockAllocationTable[cBlockAllocationTableEntry]) * VHD_SECTOR_SIZE,
1560	pImage->pu8Bitmap, pImage->cbDataBlockBitmap,
1561	pIoCtx, &pMetaXfer, NULL, NULL);
1562
1563	if (RT_SUCCESS(rc))
1564	{
1565	uint32_t cSectors = 0;
1566
1567	vdIfIoIntMetaXferRelease(pImage->pIfIo, pMetaXfer);
1568	if (vhdBlockBitmapSectorContainsData(pImage, cBATEntryIndex))
1569	{
1570	cBATEntryIndex++;
1571	cSectors = 1;
1572
1573	/*
1574	* The first sector being read is marked dirty, read as much as we
1575	* can from child. Note that only sectors that are marked dirty
1576	* must be read from child.
1577	*/
1578	while ( (cSectors < (cbToRead / VHD_SECTOR_SIZE))
1579	&& vhdBlockBitmapSectorContainsData(pImage, cBATEntryIndex))
1580	{
1581	cBATEntryIndex++;
1582	cSectors++;
1583	}
1584
1585	cbToRead = cSectors * VHD_SECTOR_SIZE;
1586
1587	LogFlowFunc(("uVhdOffset=%llu cbToRead=%u\n", uVhdOffset, cbToRead));
1588	rc = vdIfIoIntFileReadUser(pImage->pIfIo, pImage->pStorage,
1589	uVhdOffset, pIoCtx, cbToRead);
1590	}
1591	else
1592	{
1593	/*
1594	* The first sector being read is marked clean, so we should read from
1595	* our parent instead, but only as much as there are the following
1596	* clean sectors, because the block may still contain dirty sectors
1597	* further on. We just need to compute the number of clean sectors
1598	* and pass it to our caller along with the notification that they
1599	* should be read from the parent.
1600	*/
1601	cBATEntryIndex++;
1602	cSectors = 1;
1603
1604	while ( (cSectors < (cbToRead / VHD_SECTOR_SIZE))
1605	&& !vhdBlockBitmapSectorContainsData(pImage, cBATEntryIndex))
1606	{
1607	cBATEntryIndex++;
1608	cSectors++;
1609	}
1610
1611	cbToRead = cSectors * VHD_SECTOR_SIZE;
1612	LogFunc(("Sectors free: uVhdOffset=%llu cbToRead=%u\n", uVhdOffset, cbToRead));
1613	rc = VERR_VD_BLOCK_FREE;
1614	}
1615	}
1616	else
1617	AssertMsg(rc == VERR_VD_NOT_ENOUGH_METADATA, ("Reading block bitmap failed rc=%Rrc\n", rc));
1618	}
1619	}
1620	else
1621	rc = vdIfIoIntFileReadUser(pImage->pIfIo, pImage->pStorage, uOffset, pIoCtx, cbToRead);
1622
1623	if (pcbActuallyRead)
1624	*pcbActuallyRead = cbToRead;
1625
1626	LogFlowFunc(("returns rc=%Rrc\n", rc));
1627	return rc;
1628	}
1629
1630	/** @interface_method_impl{VDIMAGEBACKEND,pfnWrite} */
1631	static DECLCALLBACK(int) vhdWrite(void *pBackendData, uint64_t uOffset, size_t cbToWrite,
1632	PVDIOCTX pIoCtx, size_t pcbWriteProcess, size_t pcbPreRead,
1633	size_t *pcbPostRead, unsigned fWrite)
1634	{
1635	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
1636	int rc = VINF_SUCCESS;
1637
1638	LogFlowFunc(("pBackendData=%p uOffset=%llu pIoCtx=%#p cbToWrite=%u pcbWriteProcess=%p pcbPreRead=%p pcbPostRead=%p fWrite=%u\n",
1639	pBackendData, uOffset, pIoCtx, cbToWrite, pcbWriteProcess, pcbPreRead, pcbPostRead, fWrite));
1640
1641	AssertPtr(pImage);
1642	Assert(!(uOffset % VHD_SECTOR_SIZE));
1643	Assert(!(cbToWrite % VHD_SECTOR_SIZE));
1644	AssertPtrReturn(pIoCtx, VERR_INVALID_POINTER);
1645	AssertReturn(cbToWrite, VERR_INVALID_PARAMETER);
1646	AssertReturn(uOffset + cbToWrite <= pImage->cbSize, VERR_INVALID_PARAMETER);
1647
1648	if (pImage->pBlockAllocationTable)
1649	{
1650	/*
1651	* Get the data block first.
1652	*/
1653	uint32_t cSector = uOffset / VHD_SECTOR_SIZE;
1654	uint32_t cBlockAllocationTableEntry = cSector / pImage->cSectorsPerDataBlock;
1655	uint32_t cBATEntryIndex = cSector % pImage->cSectorsPerDataBlock;
1656	uint64_t uVhdOffset;
1657
1658	/*
1659	* Clip write range.
1660	*/
1661	cbToWrite = RT_MIN(cbToWrite, (pImage->cbDataBlock - (cBATEntryIndex * VHD_SECTOR_SIZE)));
1662
1663	/*
1664	* If the block is not allocated the content of the entry is ~0
1665	* and we need to allocate a new block. Note that while blocks are
1666	* allocated with a relatively big granularity, each sector has its
1667	* own bitmap entry, indicating whether it has been written or not.
1668	* So that means for the purposes of the higher level that the
1669	* granularity is invisible. This means there's no need to return
1670	* VERR_VD_BLOCK_FREE unless the block hasn't been allocated yet.
1671	*/
1672	if (pImage->pBlockAllocationTable[cBlockAllocationTableEntry] == ~0U)
1673	{
1674	/* Check if the block allocation should be suppressed. */
1675	if ( (fWrite & VD_WRITE_NO_ALLOC)
1676	\|\| (cbToWrite != pImage->cbDataBlock))
1677	{
1678	pcbPreRead = cBATEntryIndex VHD_SECTOR_SIZE;
1679	pcbPostRead = pImage->cSectorsPerDataBlock VHD_SECTOR_SIZE - cbToWrite - *pcbPreRead;
1680
1681	if (pcbWriteProcess)
1682	*pcbWriteProcess = cbToWrite;
1683	return VERR_VD_BLOCK_FREE;
1684	}
1685
1686	PVHDIMAGEEXPAND pExpand;
1687	pExpand = (PVHDIMAGEEXPAND)RTMemAllocZ(RT_UOFFSETOF_DYN(VHDIMAGEEXPAND,
1688	au8Bitmap[pImage->cDataBlockBitmapSectors * VHD_SECTOR_SIZE]));
1689	bool fIoInProgress = false;
1690
1691	if (!pExpand)
1692	return VERR_NO_MEMORY;
1693
1694	pExpand->cbEofOld = pImage->uCurrentEndOfFile;
1695	pExpand->idxBatAllocated = cBlockAllocationTableEntry;
1696	pExpand->idxBlockBe = RT_H2BE_U32(pImage->uCurrentEndOfFile / VHD_SECTOR_SIZE);
1697
1698	/* Set the bits for all sectors having been written. */
1699	for (uint32_t iSector = 0; iSector < (cbToWrite / VHD_SECTOR_SIZE); iSector++)
1700	{
1701	/* No need to check for a changed value because this is an initial write. */
1702	vhdBlockBitmapSectorSet(pImage, pExpand->au8Bitmap, cBATEntryIndex);
1703	cBATEntryIndex++;
1704	}
1705
1706	do
1707	{
1708	/*
1709	* Start with the sector bitmap.
1710	*/
1711	rc = vdIfIoIntFileWriteMeta(pImage->pIfIo, pImage->pStorage,
1712	pImage->uCurrentEndOfFile,
1713	pExpand->au8Bitmap,
1714	pImage->cDataBlockBitmapSectors * VHD_SECTOR_SIZE, pIoCtx,
1715	vhdAsyncExpansionDataBlockBitmapComplete,
1716	pExpand);
1717	if (RT_SUCCESS(rc))
1718	VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_BLOCKBITMAP_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_SUCCESS);
1719	else if (rc == VERR_VD_ASYNC_IO_IN_PROGRESS)
1720	fIoInProgress = true;
1721	else
1722	{
1723	VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_BLOCKBITMAP_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_FAILED);
1724	VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_USERBLOCK_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_FAILED);
1725	VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_BAT_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_FAILED);
1726	VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_FOOTER_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_FAILED);
1727	break;
1728	}
1729
1730
1731	/*
1732	* Write the new block at the current end of the file.
1733	*/
1734	rc = vdIfIoIntFileWriteUser(pImage->pIfIo, pImage->pStorage,
1735	pImage->uCurrentEndOfFile + (pImage->cDataBlockBitmapSectors + (cSector % pImage->cSectorsPerDataBlock)) * VHD_SECTOR_SIZE,
1736	pIoCtx, cbToWrite,
1737	vhdAsyncExpansionDataComplete,
1738	pExpand);
1739	if (RT_SUCCESS(rc))
1740	VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_USERBLOCK_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_SUCCESS);
1741	else if (rc == VERR_VD_ASYNC_IO_IN_PROGRESS)
1742	fIoInProgress = true;
1743	else
1744	{
1745	VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_USERBLOCK_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_FAILED);
1746	VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_BAT_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_FAILED);
1747	VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_FOOTER_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_FAILED);
1748	break;
1749	}
1750
1751	/*
1752	* Write entry in the BAT.
1753	*/
1754	rc = vdIfIoIntFileWriteMeta(pImage->pIfIo, pImage->pStorage,
1755	pImage->uBlockAllocationTableOffset + cBlockAllocationTableEntry * sizeof(uint32_t),
1756	&pExpand->idxBlockBe, sizeof(uint32_t), pIoCtx,
1757	vhdAsyncExpansionBatUpdateComplete,
1758	pExpand);
1759	if (RT_SUCCESS(rc))
1760	VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_BAT_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_SUCCESS);
1761	else if (rc == VERR_VD_ASYNC_IO_IN_PROGRESS)
1762	fIoInProgress = true;
1763	else
1764	{
1765	VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_BAT_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_FAILED);
1766	VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_FOOTER_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_FAILED);
1767	break;
1768	}
1769
1770	/*
1771	* Set the new end of the file and link the new block into the BAT.
1772	*/
1773	pImage->uCurrentEndOfFile += pImage->cDataBlockBitmapSectors * VHD_SECTOR_SIZE + pImage->cbDataBlock;
1774
1775	/* Update the footer. */
1776	rc = vdIfIoIntFileWriteMeta(pImage->pIfIo, pImage->pStorage,
1777	pImage->uCurrentEndOfFile,
1778	&pImage->vhdFooterCopy,
1779	sizeof(VHDFooter), pIoCtx,
1780	vhdAsyncExpansionFooterUpdateComplete,
1781	pExpand);
1782	if (RT_SUCCESS(rc))
1783	VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_FOOTER_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_SUCCESS);
1784	else if (rc == VERR_VD_ASYNC_IO_IN_PROGRESS)
1785	fIoInProgress = true;
1786	else
1787	{
1788	VHDIMAGEEXPAND_STATUS_SET(pExpand->fFlags, VHDIMAGEEXPAND_FOOTER_STATUS_SHIFT, VHDIMAGEEXPAND_STEP_FAILED);
1789	break;
1790	}
1791
1792	} while (0);
1793
1794	if (!fIoInProgress)
1795	vhdAsyncExpansionComplete(pImage, pIoCtx, pExpand);
1796	else
1797	rc = VERR_VD_ASYNC_IO_IN_PROGRESS;
1798	}
1799	else
1800	{
1801	/*
1802	* Calculate the real offset in the file.
1803	*/
1804	uVhdOffset = ((uint64_t)pImage->pBlockAllocationTable[cBlockAllocationTableEntry] + pImage->cDataBlockBitmapSectors + cBATEntryIndex) * VHD_SECTOR_SIZE;
1805
1806	/* Read in the block's bitmap. */
1807	PVDMETAXFER pMetaXfer;
1808	rc = vdIfIoIntFileReadMeta(pImage->pIfIo, pImage->pStorage,
1809	((uint64_t)pImage->pBlockAllocationTable[cBlockAllocationTableEntry]) * VHD_SECTOR_SIZE,
1810	pImage->pu8Bitmap,
1811	pImage->cbDataBlockBitmap, pIoCtx,
1812	&pMetaXfer, NULL, NULL);
1813	if (RT_SUCCESS(rc))
1814	{
1815	vdIfIoIntMetaXferRelease(pImage->pIfIo, pMetaXfer);
1816
1817	/* Write data. */
1818	rc = vdIfIoIntFileWriteUser(pImage->pIfIo, pImage->pStorage,
1819	uVhdOffset, pIoCtx, cbToWrite,
1820	NULL, NULL);
1821	if (RT_SUCCESS(rc) \|\| rc == VERR_VD_ASYNC_IO_IN_PROGRESS)
1822	{
1823	bool fChanged = false;
1824
1825	/* Set the bits for all sectors having been written. */
1826	for (uint32_t iSector = 0; iSector < (cbToWrite / VHD_SECTOR_SIZE); iSector++)
1827	{
1828	fChanged \|= vhdBlockBitmapSectorSet(pImage, pImage->pu8Bitmap, cBATEntryIndex);
1829	cBATEntryIndex++;
1830	}
1831
1832	/* Only write the bitmap if it was changed. */
1833	if (fChanged)
1834	{
1835	/*
1836	* Write the bitmap back.
1837	*
1838	* @note We don't have a completion callback here because we
1839	* can't do anything if the write fails for some reason.
1840	* The error will propagated to the device/guest
1841	* by the generic VD layer already and we don't need
1842	* to rollback anything here.
1843	*/
1844	rc = vdIfIoIntFileWriteMeta(pImage->pIfIo, pImage->pStorage,
1845	((uint64_t)pImage->pBlockAllocationTable[cBlockAllocationTableEntry]) * VHD_SECTOR_SIZE,
1846	pImage->pu8Bitmap,
1847	pImage->cbDataBlockBitmap,
1848	pIoCtx, NULL, NULL);
1849	}
1850	}
1851	}
1852	}
1853	}
1854	else
1855	rc = vdIfIoIntFileWriteUser(pImage->pIfIo, pImage->pStorage,
1856	uOffset, pIoCtx, cbToWrite, NULL, NULL);
1857
1858	if (pcbWriteProcess)
1859	*pcbWriteProcess = cbToWrite;
1860
1861	/* Stay on the safe side. Do not run the risk of confusing the higher
1862	* level, as that can be pretty lethal to image consistency. */
1863	*pcbPreRead = 0;
1864	*pcbPostRead = 0;
1865
1866	return rc;
1867	}
1868
1869	/** @interface_method_impl{VDIMAGEBACKEND,pfnFlush} */
1870	static DECLCALLBACK(int) vhdFlush(void *pBackendData, PVDIOCTX pIoCtx)
1871	{
1872	LogFlowFunc(("pBackendData=%#p\n", pBackendData));
1873	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
1874
1875	/* No need to write anything here. Data is always updated on a write. */
1876	int rc = vdIfIoIntFileFlush(pImage->pIfIo, pImage->pStorage, pIoCtx, NULL, NULL);
1877	LogFlowFunc(("returns %Rrc\n", rc));
1878	return rc;
1879	}
1880
1881	/** @interface_method_impl{VDIMAGEBACKEND,pfnGetVersion} */
1882	static DECLCALLBACK(unsigned) vhdGetVersion(void *pBackendData)
1883	{
1884	LogFlowFunc(("pBackendData=%#p\n", pBackendData));
1885	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
1886
1887	AssertPtrReturn(pImage, 0);
1888
1889	unsigned uVersion = 1; /*< @todo use correct version /
1890
1891	LogFlowFunc(("returns %u\n", uVersion));
1892	return uVersion;
1893	}
1894
1895	/** @interface_method_impl{VDIMAGEBACKEND,pfnGetFileSize} */
1896	static DECLCALLBACK(uint64_t) vhdGetFileSize(void *pBackendData)
1897	{
1898	LogFlowFunc(("pBackendData=%#p\n", pBackendData));
1899	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
1900	uint64_t cb = 0;
1901
1902	AssertPtrReturn(pImage, 0);
1903
1904	if (pImage->pStorage)
1905	cb = pImage->uCurrentEndOfFile + sizeof(VHDFooter);
1906
1907	LogFlowFunc(("returns %lld\n", cb));
1908	return cb;
1909	}
1910
1911	/** @interface_method_impl{VDIMAGEBACKEND,pfnGetPCHSGeometry} */
1912	static DECLCALLBACK(int) vhdGetPCHSGeometry(void *pBackendData, PVDGEOMETRY pPCHSGeometry)
1913	{
1914	LogFlowFunc(("pBackendData=%#p pPCHSGeometry=%#p\n", pBackendData, pPCHSGeometry));
1915	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
1916	int rc = VINF_SUCCESS;
1917
1918	AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
1919
1920	if (pImage->PCHSGeometry.cCylinders)
1921	*pPCHSGeometry = pImage->PCHSGeometry;
1922	else
1923	rc = VERR_VD_GEOMETRY_NOT_SET;
1924
1925	LogFlowFunc(("returns %Rrc (CHS=%u/%u/%u)\n", rc, pImage->PCHSGeometry.cCylinders,
1926	pImage->PCHSGeometry.cHeads, pImage->PCHSGeometry.cSectors));
1927	return rc;
1928	}
1929
1930	/** @interface_method_impl{VDIMAGEBACKEND,pfnSetPCHSGeometry} */
1931	static DECLCALLBACK(int) vhdSetPCHSGeometry(void *pBackendData, PCVDGEOMETRY pPCHSGeometry)
1932	{
1933	LogFlowFunc(("pBackendData=%#p pPCHSGeometry=%#p PCHS=%u/%u/%u\n",
1934	pBackendData, pPCHSGeometry, pPCHSGeometry->cCylinders, pPCHSGeometry->cHeads, pPCHSGeometry->cSectors));
1935	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
1936	int rc = VINF_SUCCESS;
1937
1938	AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
1939
1940	if (pImage->uOpenFlags & VD_OPEN_FLAGS_READONLY)
1941	rc = VERR_VD_IMAGE_READ_ONLY;
1942	else
1943	pImage->PCHSGeometry = *pPCHSGeometry;
1944
1945	LogFlowFunc(("returns %Rrc\n", rc));
1946	return rc;
1947	}
1948
1949	/** @interface_method_impl{VDIMAGEBACKEND,pfnGetLCHSGeometry} */
1950	static DECLCALLBACK(int) vhdGetLCHSGeometry(void *pBackendData, PVDGEOMETRY pLCHSGeometry)
1951	{
1952	LogFlowFunc(("pBackendData=%#p pLCHSGeometry=%#p\n", pBackendData, pLCHSGeometry));
1953	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
1954	int rc = VINF_SUCCESS;
1955
1956	AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
1957
1958	if (pImage->LCHSGeometry.cCylinders)
1959	*pLCHSGeometry = pImage->LCHSGeometry;
1960	else
1961	rc = VERR_VD_GEOMETRY_NOT_SET;
1962
1963	LogFlowFunc(("returns %Rrc (CHS=%u/%u/%u)\n", rc, pImage->LCHSGeometry.cCylinders,
1964	pImage->LCHSGeometry.cHeads, pImage->LCHSGeometry.cSectors));
1965	return rc;
1966	}
1967
1968	/** @interface_method_impl{VDIMAGEBACKEND,pfnSetLCHSGeometry} */
1969	static DECLCALLBACK(int) vhdSetLCHSGeometry(void *pBackendData, PCVDGEOMETRY pLCHSGeometry)
1970	{
1971	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
1972	int rc = VINF_SUCCESS;
1973
1974	AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
1975
1976	if (pImage->uOpenFlags & VD_OPEN_FLAGS_READONLY)
1977	rc = VERR_VD_IMAGE_READ_ONLY;
1978	else
1979	pImage->LCHSGeometry = *pLCHSGeometry;
1980
1981	LogFlowFunc(("returns %Rrc\n", rc));
1982	return rc;
1983	}
1984
1985	/** @copydoc VDIMAGEBACKEND::pfnQueryRegions */
1986	static DECLCALLBACK(int) vhdQueryRegions(void pBackendData, PCVDREGIONLIST ppRegionList)
1987	{
1988	LogFlowFunc(("pBackendData=%#p ppRegionList=%#p\n", pBackendData, ppRegionList));
1989	PVHDIMAGE pThis = (PVHDIMAGE)pBackendData;
1990
1991	AssertPtrReturn(pThis, VERR_VD_NOT_OPENED);
1992
1993	*ppRegionList = &pThis->RegionList;
1994	LogFlowFunc(("returns %Rrc\n", VINF_SUCCESS));
1995	return VINF_SUCCESS;
1996	}
1997
1998	/** @copydoc VDIMAGEBACKEND::pfnRegionListRelease */
1999	static DECLCALLBACK(void) vhdRegionListRelease(void *pBackendData, PCVDREGIONLIST pRegionList)
2000	{
2001	RT_NOREF1(pRegionList);
2002	LogFlowFunc(("pBackendData=%#p pRegionList=%#p\n", pBackendData, pRegionList));
2003	PVHDIMAGE pThis = (PVHDIMAGE)pBackendData;
2004	AssertPtr(pThis); RT_NOREF(pThis);
2005
2006	/* Nothing to do here. */
2007	}
2008
2009	/** @interface_method_impl{VDIMAGEBACKEND,pfnGetImageFlags} */
2010	static DECLCALLBACK(unsigned) vhdGetImageFlags(void *pBackendData)
2011	{
2012	LogFlowFunc(("pBackendData=%#p\n", pBackendData));
2013	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2014
2015	AssertPtrReturn(pImage, 0);
2016
2017	LogFlowFunc(("returns %#x\n", pImage->uImageFlags));
2018	return pImage->uImageFlags;
2019	}
2020
2021	/** @interface_method_impl{VDIMAGEBACKEND,pfnGetOpenFlags} */
2022	static DECLCALLBACK(unsigned) vhdGetOpenFlags(void *pBackendData)
2023	{
2024	LogFlowFunc(("pBackendData=%#p\n", pBackendData));
2025	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2026
2027	AssertPtrReturn(pImage, 0);
2028
2029	LogFlowFunc(("returns %#x\n", pImage->uOpenFlags));
2030	return pImage->uOpenFlags;
2031	}
2032
2033	/** @interface_method_impl{VDIMAGEBACKEND,pfnSetOpenFlags} */
2034	static DECLCALLBACK(int) vhdSetOpenFlags(void *pBackendData, unsigned uOpenFlags)
2035	{
2036	LogFlowFunc(("pBackendData=%#p\n uOpenFlags=%#x", pBackendData, uOpenFlags));
2037	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2038	int rc = VINF_SUCCESS;
2039
2040	/* Image must be opened and the new flags must be valid. */
2041	if (!pImage \|\| (uOpenFlags & ~( VD_OPEN_FLAGS_READONLY \| VD_OPEN_FLAGS_INFO
2042	\| VD_OPEN_FLAGS_ASYNC_IO \| VD_OPEN_FLAGS_SHAREABLE
2043	\| VD_OPEN_FLAGS_SEQUENTIAL \| VD_OPEN_FLAGS_SKIP_CONSISTENCY_CHECKS)))
2044	rc = VERR_INVALID_PARAMETER;
2045	else
2046	{
2047	/* Implement this operation via reopening the image. */
2048	rc = vhdFreeImage(pImage, false);
2049	if (RT_SUCCESS(rc))
2050	rc = vhdOpenImage(pImage, uOpenFlags);
2051	}
2052
2053	LogFlowFunc(("returns %Rrc\n", rc));
2054	return rc;
2055	}
2056
2057	/** @interface_method_impl{VDIMAGEBACKEND,pfnGetComment} */
2058	static DECLCALLBACK(int) vhdGetComment(void pBackendData, char pszComment,
2059	size_t cbComment)
2060	{
2061	RT_NOREF2(pszComment, cbComment);
2062	LogFlowFunc(("pBackendData=%#p pszComment=%#p cbComment=%zu\n", pBackendData, pszComment, cbComment));
2063	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2064
2065	AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
2066
2067	LogFlowFunc(("returns %Rrc comment='%s'\n", VERR_NOT_SUPPORTED, pszComment));
2068	return VERR_NOT_SUPPORTED;
2069	}
2070
2071	/** @interface_method_impl{VDIMAGEBACKEND,pfnSetComment} */
2072	static DECLCALLBACK(int) vhdSetComment(void pBackendData, const char pszComment)
2073	{
2074	RT_NOREF1(pszComment);
2075	LogFlowFunc(("pBackendData=%#p pszComment=\"%s\"\n", pBackendData, pszComment));
2076	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2077
2078	AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
2079
2080	int rc;
2081	if (pImage->uOpenFlags & VD_OPEN_FLAGS_READONLY)
2082	rc = VERR_VD_IMAGE_READ_ONLY;
2083	else
2084	rc = VERR_NOT_SUPPORTED;
2085
2086	LogFlowFunc(("returns %Rrc\n", rc));
2087	return rc;
2088	}
2089
2090	/** @interface_method_impl{VDIMAGEBACKEND,pfnGetUuid} */
2091	static DECLCALLBACK(int) vhdGetUuid(void *pBackendData, PRTUUID pUuid)
2092	{
2093	LogFlowFunc(("pBackendData=%#p pUuid=%#p\n", pBackendData, pUuid));
2094	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2095
2096	AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
2097
2098	*pUuid = pImage->ImageUuid;
2099
2100	LogFlowFunc(("returns %Rrc (%RTuuid)\n", VINF_SUCCESS, pUuid));
2101	return VINF_SUCCESS;
2102	}
2103
2104	/** @interface_method_impl{VDIMAGEBACKEND,pfnSetUuid} */
2105	static DECLCALLBACK(int) vhdSetUuid(void *pBackendData, PCRTUUID pUuid)
2106	{
2107	LogFlowFunc(("pBackendData=%#p Uuid=%RTuuid\n", pBackendData, pUuid));
2108	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2109	int rc = VINF_SUCCESS;
2110
2111	AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
2112
2113	if (!(pImage->uOpenFlags & VD_OPEN_FLAGS_READONLY))
2114	{
2115	pImage->ImageUuid = *pUuid;
2116	/* Update the footer copy. It will get written to disk when the image is closed. */
2117	memcpy(&pImage->vhdFooterCopy.UniqueID, pUuid, 16);
2118	/* Update checksum. */
2119	pImage->vhdFooterCopy.Checksum = 0;
2120	pImage->vhdFooterCopy.Checksum = RT_H2BE_U32(vhdChecksum(&pImage->vhdFooterCopy, sizeof(VHDFooter)));
2121
2122	/* Need to update the dynamic disk header to update the disk footer copy at the beginning. */
2123	if (!(pImage->uImageFlags & VD_IMAGE_FLAGS_FIXED))
2124	pImage->fDynHdrNeedsUpdate = true;
2125	}
2126	else
2127	rc = VERR_VD_IMAGE_READ_ONLY;
2128
2129	LogFlowFunc(("returns %Rrc\n", rc));
2130	return rc;
2131	}
2132
2133	/** @interface_method_impl{VDIMAGEBACKEND,pfnGetModificationUuid} */
2134	static DECLCALLBACK(int) vhdGetModificationUuid(void *pBackendData, PRTUUID pUuid)
2135	{
2136	RT_NOREF1(pUuid);
2137	LogFlowFunc(("pBackendData=%#p pUuid=%#p\n", pBackendData, pUuid));
2138	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2139
2140	AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
2141
2142	LogFlowFunc(("returns %Rrc (%RTuuid)\n", VERR_NOT_SUPPORTED, pUuid));
2143	return VERR_NOT_SUPPORTED;
2144	}
2145
2146	/** @interface_method_impl{VDIMAGEBACKEND,pfnSetModificationUuid} */
2147	static DECLCALLBACK(int) vhdSetModificationUuid(void *pBackendData, PCRTUUID pUuid)
2148	{
2149	RT_NOREF1(pUuid);
2150	LogFlowFunc(("pBackendData=%#p Uuid=%RTuuid\n", pBackendData, pUuid));
2151	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2152
2153	AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
2154
2155	int rc;
2156	if (pImage->uOpenFlags & VD_OPEN_FLAGS_READONLY)
2157	rc = VERR_VD_IMAGE_READ_ONLY;
2158	else
2159	rc = VERR_NOT_SUPPORTED;
2160
2161	LogFlowFunc(("returns %Rrc\n", rc));
2162	return rc;
2163	}
2164
2165	/** @interface_method_impl{VDIMAGEBACKEND,pfnGetParentUuid} */
2166	static DECLCALLBACK(int) vhdGetParentUuid(void *pBackendData, PRTUUID pUuid)
2167	{
2168	LogFlowFunc(("pBackendData=%#p pUuid=%#p\n", pBackendData, pUuid));
2169	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2170
2171	AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
2172
2173	*pUuid = pImage->ParentUuid;
2174
2175	LogFlowFunc(("returns %Rrc (%RTuuid)\n", VINF_SUCCESS, pUuid));
2176	return VINF_SUCCESS;
2177	}
2178
2179	/** @interface_method_impl{VDIMAGEBACKEND,pfnSetParentUuid} */
2180	static DECLCALLBACK(int) vhdSetParentUuid(void *pBackendData, PCRTUUID pUuid)
2181	{
2182	LogFlowFunc(("pBackendData=%#p Uuid=%RTuuid\n", pBackendData, pUuid));
2183	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2184	int rc = VINF_SUCCESS;
2185
2186	if (pImage && pImage->pStorage)
2187	{
2188	if (!(pImage->uImageFlags & VD_IMAGE_FLAGS_FIXED))
2189	{
2190	pImage->ParentUuid = *pUuid;
2191	pImage->fDynHdrNeedsUpdate = true;
2192	}
2193	else
2194	rc = VERR_VD_IMAGE_READ_ONLY;
2195	}
2196	else
2197	rc = VERR_VD_NOT_OPENED;
2198
2199	LogFlowFunc(("returns %Rrc\n", rc));
2200	return rc;
2201	}
2202
2203	/** @interface_method_impl{VDIMAGEBACKEND,pfnGetParentModificationUuid} */
2204	static DECLCALLBACK(int) vhdGetParentModificationUuid(void *pBackendData, PRTUUID pUuid)
2205	{
2206	RT_NOREF1(pUuid);
2207	LogFlowFunc(("pBackendData=%#p pUuid=%#p\n", pBackendData, pUuid));
2208	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2209
2210	AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
2211
2212	LogFlowFunc(("returns %Rrc (%RTuuid)\n", VERR_NOT_SUPPORTED, pUuid));
2213	return VERR_NOT_SUPPORTED;
2214	}
2215
2216	/** @interface_method_impl{VDIMAGEBACKEND,pfnSetParentModificationUuid} */
2217	static DECLCALLBACK(int) vhdSetParentModificationUuid(void *pBackendData, PCRTUUID pUuid)
2218	{
2219	RT_NOREF1(pUuid);
2220	LogFlowFunc(("pBackendData=%#p Uuid=%RTuuid\n", pBackendData, pUuid));
2221	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2222
2223	AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
2224
2225	int rc;
2226	if (pImage->uOpenFlags & VD_OPEN_FLAGS_READONLY)
2227	rc = VERR_VD_IMAGE_READ_ONLY;
2228	else
2229	rc = VERR_NOT_SUPPORTED;
2230
2231	LogFlowFunc(("returns %Rrc\n", rc));
2232	return rc;
2233	}
2234
2235	/** @interface_method_impl{VDIMAGEBACKEND,pfnDump} */
2236	static DECLCALLBACK(void) vhdDump(void *pBackendData)
2237	{
2238	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2239
2240	AssertPtrReturnVoid(pImage);
2241	vdIfErrorMessage(pImage->pIfError, "Header: Geometry PCHS=%u/%u/%u LCHS=%u/%u/%u cbSector=%u\n",
2242	pImage->PCHSGeometry.cCylinders, pImage->PCHSGeometry.cHeads, pImage->PCHSGeometry.cSectors,
2243	pImage->LCHSGeometry.cCylinders, pImage->LCHSGeometry.cHeads, pImage->LCHSGeometry.cSectors,
2244	VHD_SECTOR_SIZE);
2245	vdIfErrorMessage(pImage->pIfError, "Header: uuidCreation={%RTuuid}\n", &pImage->ImageUuid);
2246	vdIfErrorMessage(pImage->pIfError, "Header: uuidParent={%RTuuid}\n", &pImage->ParentUuid);
2247	}
2248
2249	/** @interface_method_impl{VDIMAGEBACKEND,pfnGetTimestamp} */
2250	static DECLCALLBACK(int) vhdGetTimestamp(void *pBackendData, PRTTIMESPEC pTimestamp)
2251	{
2252	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2253
2254	AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
2255
2256	int rc = vdIfIoIntFileGetModificationTime(pImage->pIfIo, pImage->pszFilename, pTimestamp);
2257
2258	LogFlowFunc(("returns %Rrc\n", rc));
2259	return rc;
2260	}
2261
2262	/** @interface_method_impl{VDIMAGEBACKEND,pfnGetParentTimestamp} */
2263	static DECLCALLBACK(int) vhdGetParentTimestamp(void *pBackendData, PRTTIMESPEC pTimestamp)
2264	{
2265	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2266
2267	AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
2268
2269	vhdTime2RtTime(pTimestamp, pImage->u32ParentTimestamp);
2270	LogFlowFunc(("returns %Rrc\n", VINF_SUCCESS));
2271	return VINF_SUCCESS;
2272	}
2273
2274	/** @interface_method_impl{VDIMAGEBACKEND,pfnSetParentTimestamp} */
2275	static DECLCALLBACK(int) vhdSetParentTimestamp(void *pBackendData, PCRTTIMESPEC pTimestamp)
2276	{
2277	int rc = VINF_SUCCESS;
2278	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2279
2280	AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
2281	if (pImage->uOpenFlags & VD_OPEN_FLAGS_READONLY)
2282	rc = VERR_VD_IMAGE_READ_ONLY;
2283	else
2284	{
2285	pImage->u32ParentTimestamp = vhdRtTime2VhdTime(pTimestamp);
2286	pImage->fDynHdrNeedsUpdate = true;
2287	}
2288
2289	LogFlowFunc(("returns %Rrc\n", rc));
2290	return rc;
2291	}
2292
2293	/** @interface_method_impl{VDIMAGEBACKEND,pfnGetParentFilename} */
2294	static DECLCALLBACK(int) vhdGetParentFilename(void pBackendData, char *ppszParentFilename)
2295	{
2296	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2297
2298	AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
2299	*ppszParentFilename = RTStrDup(pImage->pszParentFilename);
2300
2301	LogFlowFunc(("returns %Rrc\n", VINF_SUCCESS));
2302	return VINF_SUCCESS;
2303	}
2304
2305	/** @interface_method_impl{VDIMAGEBACKEND,pfnSetParentFilename} */
2306	static DECLCALLBACK(int) vhdSetParentFilename(void pBackendData, const char pszParentFilename)
2307	{
2308	int rc = VINF_SUCCESS;
2309	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2310
2311	AssertPtrReturn(pImage, VERR_VD_NOT_OPENED);
2312
2313	if (pImage->uOpenFlags & VD_OPEN_FLAGS_READONLY)
2314	rc = VERR_VD_IMAGE_READ_ONLY;
2315	else
2316	{
2317	if (pImage->pszParentFilename)
2318	RTStrFree(pImage->pszParentFilename);
2319	pImage->pszParentFilename = RTStrDup(pszParentFilename);
2320	if (!pImage->pszParentFilename)
2321	rc = VERR_NO_MEMORY;
2322	else
2323	pImage->fDynHdrNeedsUpdate = true;
2324	}
2325
2326	LogFlowFunc(("returns %Rrc\n", rc));
2327	return rc;
2328	}
2329
2330	/** @interface_method_impl{VDIMAGEBACKEND,pfnCompact} */
2331	static DECLCALLBACK(int) vhdCompact(void *pBackendData, unsigned uPercentStart,
2332	unsigned uPercentSpan, PVDINTERFACE pVDIfsDisk,
2333	PVDINTERFACE pVDIfsImage, PVDINTERFACE pVDIfsOperation)
2334	{
2335	RT_NOREF2(pVDIfsDisk, pVDIfsImage);
2336	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2337	int rc = VINF_SUCCESS;
2338	void *pvBuf = NULL;
2339	uint32_t *paBlocks = NULL;
2340	PVDINTERFACEPROGRESS pIfProgress = VDIfProgressGet(pVDIfsOperation);
2341
2342	PFNVDPARENTREAD pfnParentRead = NULL;
2343	void *pvParent = NULL;
2344	PVDINTERFACEPARENTSTATE pIfParentState = VDIfParentStateGet(pVDIfsOperation);
2345	if (pIfParentState)
2346	{
2347	pfnParentRead = pIfParentState->pfnParentRead;
2348	pvParent = pIfParentState->Core.pvUser;
2349	}
2350
2351	do
2352	{
2353	AssertBreakStmt(pImage, rc = VERR_INVALID_PARAMETER);
2354
2355	AssertBreakStmt(!(pImage->uOpenFlags & VD_OPEN_FLAGS_READONLY),
2356	rc = VERR_VD_IMAGE_READ_ONLY);
2357
2358	/* Reject fixed images as they don't have a BAT. */
2359	if (pImage->uImageFlags & VD_IMAGE_FLAGS_FIXED)
2360	{
2361	rc = VERR_NOT_SUPPORTED;
2362	break;
2363	}
2364
2365	if (pfnParentRead)
2366	{
2367	pvParent = RTMemTmpAlloc(pImage->cbDataBlock);
2368	AssertBreakStmt(pvParent, rc = VERR_NO_MEMORY);
2369	}
2370	pvBuf = RTMemTmpAlloc(pImage->cbDataBlock);
2371	AssertBreakStmt(pvBuf, rc = VERR_NO_MEMORY);
2372
2373	unsigned cBlocksAllocated = 0;
2374	unsigned cBlocksToMove = 0;
2375	unsigned cBlocks = pImage->cBlockAllocationTableEntries;
2376	uint32_t offBlocksStart = ~0U; /* Start offset of data blocks in sectors. */
2377	uint32_t *paBat = pImage->pBlockAllocationTable;
2378
2379	/* Count the number of allocated blocks and find the start offset for the data blocks. */
2380	for (unsigned i = 0; i < cBlocks; i++)
2381	if (paBat[i] != ~0U)
2382	{
2383	cBlocksAllocated++;
2384	if (paBat[i] < offBlocksStart)
2385	offBlocksStart = paBat[i];
2386	}
2387
2388	if (!cBlocksAllocated)
2389	{
2390	/* Nothing to do. */
2391	rc = VINF_SUCCESS;
2392	break;
2393	}
2394
2395	paBlocks = (uint32_t )RTMemTmpAllocZ(cBlocksAllocated sizeof(uint32_t));
2396	AssertBreakStmt(paBlocks, rc = VERR_NO_MEMORY);
2397
2398	/* Invalidate the back resolving array. */
2399	for (unsigned i = 0; i < cBlocksAllocated; i++)
2400	paBlocks[i] = ~0U;
2401
2402	/* Fill the back resolving table. */
2403	for (unsigned i = 0; i < cBlocks; i++)
2404	if (paBat[i] != ~0U)
2405	{
2406	unsigned idxBlock = (paBat[i] - offBlocksStart) / pImage->cSectorsPerDataBlock;
2407	if ( idxBlock < cBlocksAllocated
2408	&& paBlocks[idxBlock] == ~0U)
2409	paBlocks[idxBlock] = i;
2410	else
2411	{
2412	/* The image is in an inconsistent state. Don't go further. */
2413	rc = VERR_INVALID_STATE;
2414	break;
2415	}
2416	}
2417
2418	if (RT_FAILURE(rc))
2419	break;
2420
2421	/* Find redundant information and update the block pointers
2422	* accordingly, creating bubbles. Keep disk up to date, as this
2423	* enables cancelling. */
2424	for (unsigned i = 0; i < cBlocks; i++)
2425	{
2426	if (paBat[i] != ~0U)
2427	{
2428	unsigned idxBlock = (paBat[i] - offBlocksStart) / pImage->cSectorsPerDataBlock;
2429
2430	/* Block present in image file, read relevant data. */
2431	uint64_t u64Offset = ((uint64_t)paBat[i] + pImage->cDataBlockBitmapSectors) * VHD_SECTOR_SIZE;
2432	rc = vdIfIoIntFileReadSync(pImage->pIfIo, pImage->pStorage,
2433	u64Offset, pvBuf, pImage->cbDataBlock);
2434	if (RT_FAILURE(rc))
2435	break;
2436
2437	if (ASMBitFirstSet((volatile void )pvBuf, (uint32_t)pImage->cbDataBlock 8) == -1)
2438	{
2439	paBat[i] = UINT32_MAX;
2440	paBlocks[idxBlock] = ~0U;
2441	/* Adjust progress info, one block to be relocated. */
2442	cBlocksToMove++;
2443	}
2444	else if (pfnParentRead)
2445	{
2446	rc = pfnParentRead(pvParent, (uint64_t)i * pImage->cbDataBlock, pvParent, pImage->cbDataBlock);
2447	if (RT_FAILURE(rc))
2448	break;
2449	if (!memcmp(pvParent, pvBuf, pImage->cbDataBlock))
2450	{
2451	paBat[i] = ~0U;
2452	paBlocks[idxBlock] = ~0U;
2453	/* Adjust progress info, one block to be relocated. */
2454	cBlocksToMove++;
2455	}
2456	}
2457	}
2458
2459	vdIfProgress(pIfProgress, (uint64_t)i * uPercentSpan / (cBlocks + cBlocksToMove) + uPercentStart);
2460	}
2461
2462	if (RT_SUCCESS(rc))
2463	{
2464	/* Fill bubbles with other data (if available). */
2465	unsigned cBlocksMoved = 0;
2466	unsigned uBlockUsedPos = cBlocksAllocated;
2467	size_t cbBlock = pImage->cbDataBlock + pImage->cbDataBlockBitmap; /** < Size of whole block containing the bitmap and the user data. */
2468
2469	/* Allocate data buffer to hold the data block and allocation bitmap in front of the actual data. */
2470	RTMemTmpFree(pvBuf);
2471	pvBuf = RTMemTmpAllocZ(cbBlock);
2472	AssertBreakStmt(pvBuf, rc = VERR_NO_MEMORY);
2473
2474	for (unsigned i = 0; i < cBlocksAllocated; i++)
2475	{
2476	unsigned uBlock = paBlocks[i];
2477	if (uBlock == ~0U)
2478	{
2479	unsigned uBlockData = ~0U;
2480	while (uBlockUsedPos > i && uBlockData == ~0U)
2481	{
2482	uBlockUsedPos--;
2483	uBlockData = paBlocks[uBlockUsedPos];
2484	}
2485	/* Terminate early if there is no block which needs copying. */
2486	if (uBlockUsedPos == i)
2487	break;
2488	uint64_t u64Offset = (uint64_t)uBlockUsedPos * cbBlock
2489	+ (offBlocksStart * VHD_SECTOR_SIZE);
2490	rc = vdIfIoIntFileReadSync(pImage->pIfIo, pImage->pStorage,
2491	u64Offset, pvBuf, cbBlock);
2492	if (RT_FAILURE(rc))
2493	break;
2494
2495	u64Offset = (uint64_t)i * cbBlock
2496	+ (offBlocksStart * VHD_SECTOR_SIZE);
2497	rc = vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage,
2498	u64Offset, pvBuf, cbBlock);
2499	if (RT_FAILURE(rc))
2500	break;
2501
2502	paBat[uBlockData] = i*(pImage->cSectorsPerDataBlock + pImage->cDataBlockBitmapSectors) + offBlocksStart;
2503
2504	/* Truncate the file but leave enough room for the footer to avoid
2505	* races if other processes fill the whole harddisk. */
2506	rc = vdIfIoIntFileSetSize(pImage->pIfIo, pImage->pStorage,
2507	pImage->uCurrentEndOfFile - cbBlock + VHD_SECTOR_SIZE);
2508	if (RT_FAILURE(rc))
2509	break;
2510
2511	/* Update pointers and write footer. */
2512	pImage->uCurrentEndOfFile -= cbBlock;
2513
2514	/* We're kinda screwed if this failes. */
2515	rc = vhdUpdateFooter(pImage);
2516	if (RT_FAILURE(rc))
2517	break;
2518
2519	paBlocks[i] = uBlockData;
2520	paBlocks[uBlockUsedPos] = ~0U;
2521	cBlocksMoved++;
2522	}
2523
2524	rc = vdIfProgress(pIfProgress, (uint64_t)(cBlocks + cBlocksMoved) * uPercentSpan / (cBlocks + cBlocksToMove) + uPercentStart);
2525	}
2526	}
2527
2528	/* Write the new BAT in any case. */
2529	rc = vhdFlushImage(pImage);
2530	} while (0);
2531
2532	if (paBlocks)
2533	RTMemTmpFree(paBlocks);
2534	if (pvParent)
2535	RTMemTmpFree(pvParent);
2536	if (pvBuf)
2537	RTMemTmpFree(pvBuf);
2538
2539	if (RT_SUCCESS(rc))
2540	vdIfProgress(pIfProgress, uPercentStart + uPercentSpan);
2541
2542	LogFlowFunc(("returns %Rrc\n", rc));
2543	return rc;
2544	}
2545
2546	/** @interface_method_impl{VDIMAGEBACKEND,pfnResize} */
2547	static DECLCALLBACK(int) vhdResize(void *pBackendData, uint64_t cbSize,
2548	PCVDGEOMETRY pPCHSGeometry, PCVDGEOMETRY pLCHSGeometry,
2549	unsigned uPercentStart, unsigned uPercentSpan,
2550	PVDINTERFACE pVDIfsDisk, PVDINTERFACE pVDIfsImage,
2551	PVDINTERFACE pVDIfsOperation)
2552	{
2553	RT_NOREF5(uPercentSpan, uPercentStart, pVDIfsDisk, pVDIfsImage, pVDIfsOperation);
2554	PVHDIMAGE pImage = (PVHDIMAGE)pBackendData;
2555	int rc = VINF_SUCCESS;
2556
2557	/* Making the image smaller is not supported at the moment. */
2558	if (cbSize < pImage->cbSize)
2559	rc = VERR_VD_SHRINK_NOT_SUPPORTED;
2560	else if (pImage->uImageFlags & VD_IMAGE_FLAGS_FIXED)
2561	rc = VERR_NOT_SUPPORTED;
2562	else if (cbSize > pImage->cbSize)
2563	{
2564	unsigned cBlocksAllocated = 0;
2565	size_t cbBlock = pImage->cbDataBlock + pImage->cbDataBlockBitmap; /** < Size of a block including the sector bitmap. */
2566	uint32_t cBlocksNew = cbSize / pImage->cbDataBlock; /** < New number of blocks in the image after the resize */
2567	if (cbSize % pImage->cbDataBlock)
2568	cBlocksNew++;
2569
2570	uint32_t cBlocksOld = pImage->cBlockAllocationTableEntries; /** < Number of blocks before the resize. */
2571	uint64_t cbBlockspaceNew = RT_ALIGN_32(cBlocksNew * sizeof(uint32_t), VHD_SECTOR_SIZE); /** < Required space for the block array after the resize. */
2572	uint64_t offStartDataNew = RT_ALIGN_32(pImage->uBlockAllocationTableOffset + cbBlockspaceNew, VHD_SECTOR_SIZE); /** < New start offset for block data after the resize */
2573	uint64_t offStartDataOld = ~0ULL;
2574
2575	/* Go through the BAT and find the data start offset. */
2576	for (unsigned idxBlock = 0; idxBlock < pImage->cBlockAllocationTableEntries; idxBlock++)
2577	{
2578	if (pImage->pBlockAllocationTable[idxBlock] != ~0U)
2579	{
2580	uint64_t offStartBlock = (uint64_t)pImage->pBlockAllocationTable[idxBlock] * VHD_SECTOR_SIZE;
2581	if (offStartBlock < offStartDataOld)
2582	offStartDataOld = offStartBlock;
2583	cBlocksAllocated++;
2584	}
2585	}
2586
2587	if ( offStartDataOld != offStartDataNew
2588	&& cBlocksAllocated > 0)
2589	{
2590	/* Calculate how many sectors nee to be relocated. */
2591	uint64_t cbOverlapping = offStartDataNew - offStartDataOld;
2592	unsigned cBlocksReloc = (unsigned)(cbOverlapping / cbBlock);
2593	if (cbOverlapping % cbBlock)
2594	cBlocksReloc++;
2595
2596	cBlocksReloc = RT_MIN(cBlocksReloc, cBlocksAllocated);
2597	offStartDataNew = offStartDataOld;
2598
2599	/* Do the relocation. */
2600	LogFlow(("Relocating %u blocks\n", cBlocksReloc));
2601
2602	/*
2603	* Get the blocks we need to relocate first, they are appended to the end
2604	* of the image.
2605	*/
2606	void pvBuf = NULL, pvZero = NULL;
2607	do
2608	{
2609	/* Allocate data buffer. */
2610	pvBuf = RTMemAllocZ(cbBlock);
2611	if (!pvBuf)
2612	{
2613	rc = VERR_NO_MEMORY;
2614	break;
2615	}
2616
2617	/* Allocate buffer for overwriting with zeroes. */
2618	pvZero = RTMemAllocZ(cbBlock);
2619	if (!pvZero)
2620	{
2621	rc = VERR_NO_MEMORY;
2622	break;
2623	}
2624
2625	for (unsigned i = 0; i < cBlocksReloc; i++)
2626	{
2627	uint32_t uBlock = offStartDataNew / VHD_SECTOR_SIZE;
2628
2629	/* Search the index in the block table. */
2630	for (unsigned idxBlock = 0; idxBlock < cBlocksOld; idxBlock++)
2631	{
2632	if (pImage->pBlockAllocationTable[idxBlock] == uBlock)
2633	{
2634	/* Read data and append to the end of the image. */
2635	rc = vdIfIoIntFileReadSync(pImage->pIfIo, pImage->pStorage,
2636	offStartDataNew, pvBuf, cbBlock);
2637	if (RT_FAILURE(rc))
2638	break;
2639
2640	rc = vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage,
2641	pImage->uCurrentEndOfFile, pvBuf, cbBlock);
2642	if (RT_FAILURE(rc))
2643	break;
2644
2645	/* Zero out the old block area. */
2646	rc = vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage,
2647	offStartDataNew, pvZero, cbBlock);
2648	if (RT_FAILURE(rc))
2649	break;
2650
2651	/* Update block counter. */
2652	pImage->pBlockAllocationTable[idxBlock] = pImage->uCurrentEndOfFile / VHD_SECTOR_SIZE;
2653
2654	pImage->uCurrentEndOfFile += cbBlock;
2655
2656	/* Continue with the next block. */
2657	break;
2658	}
2659	}
2660
2661	if (RT_FAILURE(rc))
2662	break;
2663
2664	offStartDataNew += cbBlock;
2665	}
2666	} while (0);
2667
2668	if (pvBuf)
2669	RTMemFree(pvBuf);
2670	if (pvZero)
2671	RTMemFree(pvZero);
2672	}
2673
2674	/*
2675	* Relocation done, expand the block array and update the header with
2676	* the new data.
2677	*/
2678	if (RT_SUCCESS(rc))
2679	{
2680	uint32_t paBlocksNew = (uint32_t )RTMemRealloc(pImage->pBlockAllocationTable, cBlocksNew * sizeof(uint32_t));
2681	if (paBlocksNew)
2682	{
2683	pImage->pBlockAllocationTable = paBlocksNew;
2684
2685	/* Mark the new blocks as unallocated. */
2686	for (unsigned idxBlock = cBlocksOld; idxBlock < cBlocksNew; idxBlock++)
2687	pImage->pBlockAllocationTable[idxBlock] = ~0U;
2688	}
2689	else
2690	rc = VERR_NO_MEMORY;
2691
2692	if (RT_SUCCESS(rc))
2693	{
2694	/* Write the block array before updating the rest. */
2695	rc = vdIfIoIntFileWriteSync(pImage->pIfIo, pImage->pStorage,
2696	pImage->uBlockAllocationTableOffset,
2697	pImage->pBlockAllocationTable,
2698	cBlocksNew * sizeof(uint32_t));
2699	}
2700
2701	if (RT_SUCCESS(rc))
2702	{
2703	/* Update size and new block count. */
2704	pImage->cBlockAllocationTableEntries = cBlocksNew;
2705	pImage->cbSize = cbSize;
2706
2707	/* Update geometry. */
2708	pImage->PCHSGeometry = *pPCHSGeometry;
2709	pImage->LCHSGeometry = *pLCHSGeometry;
2710	}
2711	}
2712
2713	/* Update header information in base image file. */
2714	pImage->fDynHdrNeedsUpdate = true;
2715	vhdFlushImage(pImage);
2716	}
2717	/* Same size doesn't change the image at all. */
2718
2719	LogFlowFunc(("returns %Rrc\n", rc));
2720	return rc;
2721	}
2722
2723	/** @interface_method_impl{VDIMAGEBACKEND,pfnRepair} */
2724	static DECLCALLBACK(int) vhdRepair(const char *pszFilename, PVDINTERFACE pVDIfsDisk,
2725	PVDINTERFACE pVDIfsImage, uint32_t fFlags)
2726	{
2727	LogFlowFunc(("pszFilename=\"%s\" pVDIfsDisk=%#p pVDIfsImage=%#p\n", pszFilename, pVDIfsDisk, pVDIfsImage));
2728	int rc;
2729	PVDINTERFACEERROR pIfError;
2730	PVDINTERFACEIOINT pIfIo;
2731	PVDIOSTORAGE pStorage = NULL;
2732	uint64_t cbFile;
2733	VHDFooter vhdFooter;
2734	VHDDynamicDiskHeader dynamicDiskHeader;
2735	uint32_t *paBat = NULL;
2736	uint32_t *pu32BlockBitmap = NULL;
2737
2738	pIfIo = VDIfIoIntGet(pVDIfsImage);
2739	AssertPtrReturn(pIfIo, VERR_INVALID_PARAMETER);
2740
2741	pIfError = VDIfErrorGet(pVDIfsDisk);
2742
2743	do
2744	{
2745	uint64_t offDynamicDiskHeader = 0;
2746	uint64_t offBat = 0;
2747	uint64_t offFooter = 0;
2748	uint32_t cBatEntries = 0;
2749	bool fDynamic = false;
2750	bool fRepairFooter = false;
2751	bool fRepairBat = false;
2752	bool fRepairDynHeader = false;
2753
2754	rc = vdIfIoIntFileOpen(pIfIo, pszFilename,
2755	VDOpenFlagsToFileOpenFlags( fFlags & VD_REPAIR_DRY_RUN
2756	? VD_OPEN_FLAGS_READONLY
2757	: 0,
2758	false /* fCreate */),
2759	&pStorage);
2760	if (RT_FAILURE(rc))
2761	{
2762	rc = vdIfError(pIfError, rc, RT_SRC_POS, "Failed to open image \"%s\"", pszFilename);
2763	break;
2764	}
2765
2766	rc = vdIfIoIntFileGetSize(pIfIo, pStorage, &cbFile);
2767	if (RT_FAILURE(rc))
2768	{
2769	rc = vdIfError(pIfError, rc, RT_SRC_POS, "Failed to query image size");
2770	break;
2771	}
2772
2773	if (cbFile < sizeof(VHDFooter))
2774	{
2775	rc = vdIfError(pIfError, VERR_VD_INVALID_SIZE, RT_SRC_POS,
2776	"Image must be at least %u bytes (got %llu)",
2777	sizeof(VHDFooter), cbFile);
2778	break;
2779	}
2780
2781	rc = vdIfIoIntFileReadSync(pIfIo, pStorage, cbFile - sizeof(VHDFooter),
2782	&vhdFooter, sizeof(VHDFooter));
2783	if (RT_FAILURE(rc))
2784	{
2785	rc = vdIfError(pIfError, rc, RT_SRC_POS, "Failed to read footer of image");
2786	break;
2787	}
2788
2789	if (memcmp(vhdFooter.Cookie, VHD_FOOTER_COOKIE, VHD_FOOTER_COOKIE_SIZE) != 0)
2790	{
2791	/* Dynamic images have a backup at the beginning of the image. */
2792	rc = vdIfIoIntFileReadSync(pIfIo, pStorage, 0,
2793	&vhdFooter, sizeof(VHDFooter));
2794	if (RT_FAILURE(rc))
2795	{
2796	rc = vdIfError(pIfError, rc, RT_SRC_POS, "Failed to read header of image");
2797	break;
2798	}
2799
2800	/*
2801	* Check for the header, if this fails the image is either completely corrupted
2802	* and impossible to repair or in another format.
2803	*/
2804	if (memcmp(vhdFooter.Cookie, VHD_FOOTER_COOKIE, VHD_FOOTER_COOKIE_SIZE) != 0)
2805	{
2806	rc = vdIfError(pIfError, VERR_VD_IMAGE_REPAIR_IMPOSSIBLE, RT_SRC_POS,
2807	"No valid VHD structures found");
2808	break;
2809	}
2810	else
2811	vdIfErrorMessage(pIfError, "Missing footer structure, using backup\n");
2812
2813	/* Remember to fix the footer structure. */
2814	fRepairFooter = true;
2815	}
2816
2817	offFooter = cbFile - sizeof(VHDFooter);
2818
2819	/* Verify that checksums match. */
2820	uint32_t u32ChkSumOld = RT_BE2H_U32(vhdFooter.Checksum);
2821	vhdFooter.Checksum = 0;
2822	uint32_t u32ChkSum = vhdChecksum(&vhdFooter, sizeof(VHDFooter));
2823
2824	vhdFooter.Checksum = RT_H2BE_U32(u32ChkSum);
2825
2826	if (u32ChkSumOld != u32ChkSum)
2827	{
2828	vdIfErrorMessage(pIfError, "Checksum is invalid (should be %u got %u), repairing\n",
2829	u32ChkSum, u32ChkSumOld);
2830	fRepairFooter = true;
2831	break;
2832	}
2833
2834	switch (RT_BE2H_U32(vhdFooter.DiskType))
2835	{
2836	case VHD_FOOTER_DISK_TYPE_FIXED:
2837	fDynamic = false;
2838	break;
2839	case VHD_FOOTER_DISK_TYPE_DYNAMIC:
2840	fDynamic = true;
2841	break;
2842	case VHD_FOOTER_DISK_TYPE_DIFFERENCING:
2843	fDynamic = true;
2844	break;
2845	default:
2846	{
2847	rc = vdIfError(pIfError, VERR_VD_IMAGE_REPAIR_IMPOSSIBLE, RT_SRC_POS,
2848	"VHD image type %u is not supported",
2849	RT_BE2H_U32(vhdFooter.DiskType));
2850	break;
2851	}
2852	}
2853
2854	/* Load and check dynamic disk header if required. */
2855	if (fDynamic)
2856	{
2857	size_t cbBlock;
2858
2859	offDynamicDiskHeader = RT_BE2H_U64(vhdFooter.DataOffset);
2860	if (offDynamicDiskHeader + sizeof(VHDDynamicDiskHeader) > cbFile)
2861	{
2862	rc = vdIfError(pIfError, VERR_VD_IMAGE_REPAIR_IMPOSSIBLE, RT_SRC_POS,
2863	"VHD image type is not supported");
2864	break;
2865	}
2866
2867	rc = vdIfIoIntFileReadSync(pIfIo, pStorage, offDynamicDiskHeader,
2868	&dynamicDiskHeader, sizeof(VHDDynamicDiskHeader));
2869	if (RT_FAILURE(rc))
2870	{
2871	rc = vdIfError(pIfError, VERR_VD_IMAGE_REPAIR_IMPOSSIBLE, RT_SRC_POS,
2872	"Failed to read dynamic disk header (at %llu), %Rrc",
2873	offDynamicDiskHeader, rc);
2874	break;
2875	}
2876
2877	/* Verify that checksums match. */
2878	u32ChkSumOld = RT_BE2H_U32(dynamicDiskHeader.Checksum);
2879	dynamicDiskHeader.Checksum = 0;
2880	u32ChkSum = vhdChecksum(&dynamicDiskHeader, sizeof(VHDDynamicDiskHeader));
2881
2882	dynamicDiskHeader.Checksum = RT_H2BE_U32(u32ChkSum);
2883
2884	if (u32ChkSumOld != u32ChkSum)
2885	{
2886	vdIfErrorMessage(pIfError, "Checksum of dynamic disk header is invalid (should be %u got %u), repairing\n",
2887	u32ChkSum, u32ChkSumOld);
2888	fRepairDynHeader = true;
2889	break;
2890	}
2891
2892	/* Read the block allocation table and fix any inconsistencies. */
2893	offBat = RT_BE2H_U64(dynamicDiskHeader.TableOffset);
2894	cBatEntries = RT_BE2H_U32(dynamicDiskHeader.MaxTableEntries);
2895	cbBlock = RT_BE2H_U32(dynamicDiskHeader.BlockSize);
2896	cbBlock += cbBlock / VHD_SECTOR_SIZE / 8;
2897
2898	if (offBat + cBatEntries * sizeof(uint32_t) > cbFile)
2899	{
2900	rc = vdIfError(pIfError, VERR_VD_IMAGE_REPAIR_IMPOSSIBLE, RT_SRC_POS,
2901	"Block allocation table is not inside the image");
2902	break;
2903	}
2904
2905	paBat = (uint32_t )RTMemAllocZ(cBatEntries sizeof(uint32_t));
2906	if (!paBat)
2907	{
2908	rc = vdIfError(pIfError, VERR_VD_IMAGE_REPAIR_IMPOSSIBLE, RT_SRC_POS,
2909	"Could not allocate memory for the block allocation table (%u bytes)",
2910	cBatEntries * sizeof(uint32_t));
2911	break;
2912	}
2913
2914	rc = vdIfIoIntFileReadSync(pIfIo, pStorage, offBat, paBat,
2915	cBatEntries * sizeof(uint32_t));
2916	if (RT_FAILURE(rc))
2917	{
2918	rc = vdIfError(pIfError, VERR_VD_IMAGE_REPAIR_IMPOSSIBLE, RT_SRC_POS,
2919	"Could not read block allocation table (at %llu), %Rrc",
2920	offBat, rc);
2921	break;
2922	}
2923
2924	pu32BlockBitmap = (uint32_t *)RTMemAllocZ(RT_ALIGN_Z(cBatEntries / 8, 4));
2925	if (!pu32BlockBitmap)
2926	{
2927	rc = vdIfError(pIfError, VERR_NO_MEMORY, RT_SRC_POS,
2928	"Failed to allocate memory for block bitmap");
2929	break;
2930	}
2931
2932	uint32_t idxMinBlock = UINT32_C(0xffffffff);
2933	for (uint32_t i = 0; i < cBatEntries; i++)
2934	{
2935	paBat[i] = RT_BE2H_U32(paBat[i]);
2936	if (paBat[i] < idxMinBlock)
2937	idxMinBlock = paBat[i];
2938	}
2939
2940	vdIfErrorMessage(pIfError, "First data block at sector %u\n", idxMinBlock);
2941
2942	for (uint32_t i = 0; i < cBatEntries; i++)
2943	{
2944	if (paBat[i] != UINT32_C(0xffffffff))
2945	{
2946	uint64_t offBlock =(uint64_t)paBat[i] * VHD_SECTOR_SIZE;
2947
2948	/*
2949	* Check that the offsets are valid (inside of the image) and
2950	* that there are no double references.
2951	*/
2952	if (offBlock + cbBlock > cbFile)
2953	{
2954	vdIfErrorMessage(pIfError, "Entry %u points to invalid offset %llu, clearing\n",
2955	i, offBlock);
2956	paBat[i] = UINT32_C(0xffffffff);
2957	fRepairBat = true;
2958	}
2959	else if (offBlock + cbBlock > offFooter)
2960	{
2961	vdIfErrorMessage(pIfError, "Entry %u intersects with footer, aligning footer\n",
2962	i);
2963	offFooter = offBlock + cbBlock;
2964	fRepairBat = true;
2965	}
2966
2967	if ( paBat[i] != UINT32_C(0xffffffff)
2968	&& ASMBitTestAndSet(pu32BlockBitmap, (uint32_t)((paBat[i] - idxMinBlock) / (cbBlock / VHD_SECTOR_SIZE))))
2969	{
2970	vdIfErrorMessage(pIfError, "Entry %u points to an already referenced data block, clearing\n",
2971	i);
2972	paBat[i] = UINT32_C(0xffffffff);
2973	fRepairBat = true;
2974	}
2975	}
2976	}
2977	}
2978
2979	/* Write repaired structures now. */
2980	if (!(fRepairBat \|\| fRepairDynHeader \|\| fRepairFooter))
2981	vdIfErrorMessage(pIfError, "VHD image is in a consistent state, no repair required\n");
2982	else if (!(fFlags & VD_REPAIR_DRY_RUN))
2983	{
2984	if (fRepairBat)
2985	{
2986	for (uint32_t i = 0; i < cBatEntries; i++)
2987	paBat[i] = RT_H2BE_U32(paBat[i]);
2988
2989	vdIfErrorMessage(pIfError, "Writing repaired block allocation table...\n");
2990
2991	rc = vdIfIoIntFileWriteSync(pIfIo, pStorage, offBat, paBat,
2992	cBatEntries * sizeof(uint32_t));
2993	if (RT_FAILURE(rc))
2994	{
2995	rc = vdIfError(pIfError, VERR_VD_IMAGE_REPAIR_IMPOSSIBLE, RT_SRC_POS,
2996	"Could not write repaired block allocation table (at %llu), %Rrc",
2997	offBat, rc);
2998	break;
2999	}
3000	}
3001
3002	if (fRepairDynHeader)
3003	{
3004	Assert(fDynamic);
3005
3006	vdIfErrorMessage(pIfError, "Writing repaired dynamic disk header...\n");
3007	rc = vdIfIoIntFileWriteSync(pIfIo, pStorage, offDynamicDiskHeader, &dynamicDiskHeader,
3008	sizeof(VHDDynamicDiskHeader));
3009	if (RT_FAILURE(rc))
3010	{
3011	rc = vdIfError(pIfError, VERR_VD_IMAGE_REPAIR_IMPOSSIBLE, RT_SRC_POS,
3012	"Could not write repaired dynamic disk header (at %llu), %Rrc",
3013	offDynamicDiskHeader, rc);
3014	break;
3015	}
3016	}
3017
3018	if (fRepairFooter)
3019	{
3020	vdIfErrorMessage(pIfError, "Writing repaired Footer...\n");
3021
3022	if (fDynamic)
3023	{
3024	/* Write backup at image beginning. */
3025	rc = vdIfIoIntFileWriteSync(pIfIo, pStorage, 0, &vhdFooter,
3026	sizeof(VHDFooter));
3027	if (RT_FAILURE(rc))
3028	{
3029	rc = vdIfError(pIfError, VERR_VD_IMAGE_REPAIR_IMPOSSIBLE, RT_SRC_POS,
3030	"Could not write repaired backup footer (at %llu), %Rrc",
3031	0, rc);
3032	break;
3033	}
3034	}
3035
3036	rc = vdIfIoIntFileWriteSync(pIfIo, pStorage, offFooter, &vhdFooter,
3037	sizeof(VHDFooter));
3038	if (RT_FAILURE(rc))
3039	{
3040	rc = vdIfError(pIfError, VERR_VD_IMAGE_REPAIR_IMPOSSIBLE, RT_SRC_POS,
3041	"Could not write repaired footer (at %llu), %Rrc",
3042	cbFile - sizeof(VHDFooter), rc);
3043	break;
3044	}
3045	}
3046
3047	vdIfErrorMessage(pIfError, "Corrupted VHD image repaired successfully\n");
3048	}
3049	} while(0);
3050
3051	if (paBat)
3052	RTMemFree(paBat);
3053
3054	if (pu32BlockBitmap)
3055	RTMemFree(pu32BlockBitmap);
3056
3057	if (pStorage)
3058	{
3059	int rc2 = vdIfIoIntFileClose(pIfIo, pStorage);
3060	if (RT_SUCCESS(rc))
3061	rc = rc2; /* Propagate status code only when repairing the image was successful. */
3062	}
3063
3064	LogFlowFunc(("returns %Rrc\n", rc));
3065	return rc;
3066	}
3067
3068
3069	const VDIMAGEBACKEND g_VhdBackend =
3070	{
3071	/* u32Version */
3072	VD_IMGBACKEND_VERSION,
3073	/* pszBackendName */
3074	"VHD",
3075	/* uBackendCaps */
3076	VD_CAP_UUID \| VD_CAP_DIFF \| VD_CAP_FILE \|
3077	VD_CAP_CREATE_FIXED \| VD_CAP_CREATE_DYNAMIC \|
3078	VD_CAP_ASYNC \| VD_CAP_VFS \| VD_CAP_PREFERRED,
3079	/* paFileExtensions */
3080	s_aVhdFileExtensions,
3081	/* paConfigInfo */
3082	NULL,
3083	/* pfnProbe */
3084	vhdProbe,
3085	/* pfnOpen */
3086	vhdOpen,
3087	/* pfnCreate */
3088	vhdCreate,
3089	/* pfnRename */
3090	vhdRename,
3091	/* pfnClose */
3092	vhdClose,
3093	/* pfnRead */
3094	vhdRead,
3095	/* pfnWrite */
3096	vhdWrite,
3097	/* pfnFlush */
3098	vhdFlush,
3099	/* pfnDiscard */
3100	NULL,
3101	/* pfnGetVersion */
3102	vhdGetVersion,
3103	/* pfnGetFileSize */
3104	vhdGetFileSize,
3105	/* pfnGetPCHSGeometry */
3106	vhdGetPCHSGeometry,
3107	/* pfnSetPCHSGeometry */
3108	vhdSetPCHSGeometry,
3109	/* pfnGetLCHSGeometry */
3110	vhdGetLCHSGeometry,
3111	/* pfnSetLCHSGeometry */
3112	vhdSetLCHSGeometry,
3113	/* pfnQueryRegions */
3114	vhdQueryRegions,
3115	/* pfnRegionListRelease */
3116	vhdRegionListRelease,
3117	/* pfnGetImageFlags */
3118	vhdGetImageFlags,
3119	/* pfnGetOpenFlags */
3120	vhdGetOpenFlags,
3121	/* pfnSetOpenFlags */
3122	vhdSetOpenFlags,
3123	/* pfnGetComment */
3124	vhdGetComment,
3125	/* pfnSetComment */
3126	vhdSetComment,
3127	/* pfnGetUuid */
3128	vhdGetUuid,
3129	/* pfnSetUuid */
3130	vhdSetUuid,
3131	/* pfnGetModificationUuid */
3132	vhdGetModificationUuid,
3133	/* pfnSetModificationUuid */
3134	vhdSetModificationUuid,
3135	/* pfnGetParentUuid */
3136	vhdGetParentUuid,
3137	/* pfnSetParentUuid */
3138	vhdSetParentUuid,
3139	/* pfnGetParentModificationUuid */
3140	vhdGetParentModificationUuid,
3141	/* pfnSetParentModificationUuid */
3142	vhdSetParentModificationUuid,
3143	/* pfnDump */
3144	vhdDump,
3145	/* pfnGetTimestamp */
3146	vhdGetTimestamp,
3147	/* pfnGetParentTimestamp */
3148	vhdGetParentTimestamp,
3149	/* pfnSetParentTimestamp */
3150	vhdSetParentTimestamp,
3151	/* pfnGetParentFilename */
3152	vhdGetParentFilename,
3153	/* pfnSetParentFilename */
3154	vhdSetParentFilename,
3155	/* pfnComposeLocation */
3156	genericFileComposeLocation,
3157	/* pfnComposeName */
3158	genericFileComposeName,
3159	/* pfnCompact */
3160	vhdCompact,
3161	/* pfnResize */
3162	vhdResize,
3163	/* pfnRepair */
3164	vhdRepair,
3165	/* pfnTraverseMetadata */
3166	NULL,
3167	/* u32VersionEnd */
3168	VD_IMGBACKEND_VERSION
3169	};

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source: vbox/trunk/src/VBox/Storage/VHD.cpp@ 90802

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