VCICache.cpp@ 93231

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1	/* $Id: VCICache.cpp 93115 2022-01-01 11:31:46Z vboxsync $ */
2	/** @file
3	* VCICacheCore - VirtualBox Cache Image, Core Code.
4	*/
5
6	/*
7	* Copyright (C) 2006-2022 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_RAW /** @todo logging group */
23	#include <VBox/vd-cache-backend.h>
24	#include <VBox/err.h>
25
26	#include <VBox/log.h>
27	#include <iprt/assert.h>
28	#include <iprt/alloc.h>
29	#include <iprt/file.h>
30	#include <iprt/asm.h>
31
32	#include "VDBackends.h"
33
34	/*******************************************************************************
35	* On disk data structures *
36	*******************************************************************************/
37
38	/** @note All structures which are written to the disk are written in camel case
39	* and packed. */
40
41	/** Block size used internally, because we cache sectors the smallest unit we
42	* have to care about is 512 bytes. */
43	#define VCI_BLOCK_SIZE 512
44
45	/** Convert block number/size to byte offset/size. */
46	#define VCI_BLOCK2BYTE(u) ((uint64_t)(u) << 9)
47
48	/** Convert byte offset/size to block number/size. */
49	#define VCI_BYTE2BLOCK(u) ((u) >> 9)
50
51	/**
52	* The VCI header - at the beginning of the file.
53	*
54	* All entries a stored in little endian order.
55	*/
56	#pragma pack(1)
57	typedef struct VciHdr
58	{
59	/** The signature to identify a cache image. */
60	uint32_t u32Signature;
61	/** Version of the layout of metadata in the cache. */
62	uint32_t u32Version;
63	/** Maximum size of the cache file in blocks.
64	* This includes all metadata. */
65	uint64_t cBlocksCache;
66	/** Flag indicating whether the cache was closed cleanly. */
67	uint8_t fUncleanShutdown;
68	/** Cache type. */
69	uint32_t u32CacheType;
70	/** Offset of the B+-Tree root in the image in blocks. */
71	uint64_t offTreeRoot;
72	/** Offset of the block allocation bitmap in blocks. */
73	uint64_t offBlkMap;
74	/** Size of the block allocation bitmap in blocks. */
75	uint32_t cBlkMap;
76	/** UUID of the image. */
77	RTUUID uuidImage;
78	/** Modification UUID for the cache. */
79	RTUUID uuidModification;
80	/** Reserved for future use. */
81	uint8_t abReserved[951];
82	} VciHdr, *PVciHdr;
83	#pragma pack()
84	AssertCompileSize(VciHdr, 2 * VCI_BLOCK_SIZE);
85
86	/** VCI signature to identify a valid image. */
87	#define VCI_HDR_SIGNATURE UINT32_C(0x00494356) /* \0ICV */
88	/** Current version we support. */
89	#define VCI_HDR_VERSION UINT32_C(0x00000001)
90
91	/** Value for an unclean cache shutdown. */
92	#define VCI_HDR_UNCLEAN_SHUTDOWN UINT8_C(0x01)
93	/** Value for a clean cache shutdown. */
94	#define VCI_HDR_CLEAN_SHUTDOWN UINT8_C(0x00)
95
96	/** Cache type: Dynamic image growing to the maximum value. */
97	#define VCI_HDR_CACHE_TYPE_DYNAMIC UINT32_C(0x00000001)
98	/** Cache type: Fixed image, space is preallocated. */
99	#define VCI_HDR_CACHE_TYPE_FIXED UINT32_C(0x00000002)
100
101	/**
102	* On disk representation of an extent describing a range of cached data.
103	*
104	* All entries a stored in little endian order.
105	*/
106	#pragma pack(1)
107	typedef struct VciCacheExtent
108	{
109	/** Block address of the previous extent in the LRU list. */
110	uint64_t u64ExtentPrev;
111	/** Block address of the next extent in the LRU list. */
112	uint64_t u64ExtentNext;
113	/** Flags (for compression, encryption etc.) - currently unused and should be always 0. */
114	uint8_t u8Flags;
115	/** Reserved */
116	uint8_t u8Reserved;
117	/** First block of cached data the extent represents. */
118	uint64_t u64BlockOffset;
119	/** Number of blocks the extent represents. */
120	uint32_t u32Blocks;
121	/** First block in the image where the data is stored. */
122	uint64_t u64BlockAddr;
123	} VciCacheExtent, *PVciCacheExtent;
124	#pragma pack()
125	AssertCompileSize(VciCacheExtent, 38);
126
127	/**
128	* On disk representation of an internal node.
129	*
130	* All entries a stored in little endian order.
131	*/
132	#pragma pack(1)
133	typedef struct VciTreeNodeInternal
134	{
135	/** First block of cached data the internal node represents. */
136	uint64_t u64BlockOffset;
137	/** Number of blocks the internal node represents. */
138	uint32_t u32Blocks;
139	/** Block address in the image where the next node in the tree is stored. */
140	uint64_t u64ChildAddr;
141	} VciTreeNodeInternal, *PVciTreeNodeInternal;
142	#pragma pack()
143	AssertCompileSize(VciTreeNodeInternal, 20);
144
145	/**
146	* On-disk representation of a node in the B+-Tree.
147	*
148	* All entries a stored in little endian order.
149	*/
150	#pragma pack(1)
151	typedef struct VciTreeNode
152	{
153	/** Type of the node (root, internal, leaf). */
154	uint8_t u8Type;
155	/** Data in the node. */
156	uint8_t au8Data[4095];
157	} VciTreeNode, *PVciTreeNode;
158	#pragma pack()
159	AssertCompileSize(VciTreeNode, 8 * VCI_BLOCK_SIZE);
160
161	/** Node type: Internal node containing links to other nodes (VciTreeNodeInternal). */
162	#define VCI_TREE_NODE_TYPE_INTERNAL UINT8_C(0x01)
163	/** Node type: Leaf of the tree (VciCacheExtent). */
164	#define VCI_TREE_NODE_TYPE_LEAF UINT8_C(0x02)
165
166	/** Number of cache extents described by one node. */
167	#define VCI_TREE_EXTENTS_PER_NODE ((sizeof(VciTreeNode)-1) / sizeof(VciCacheExtent))
168	/** Number of internal nodes managed by one tree node. */
169	#define VCI_TREE_INTERNAL_NODES_PER_NODE ((sizeof(VciTreeNode)-1) / sizeof(VciTreeNodeInternal))
170
171	/**
172	* VCI block bitmap header.
173	*
174	* All entries a stored in little endian order.
175	*/
176	#pragma pack(1)
177	typedef struct VciBlkMap
178	{
179	/** Magic of the block bitmap. */
180	uint32_t u32Magic;
181	/** Version of the block bitmap. */
182	uint32_t u32Version;
183	/** Number of blocks this block map manages. */
184	uint64_t cBlocks;
185	/** Number of free blocks. */
186	uint64_t cBlocksFree;
187	/** Number of blocks allocated for metadata. */
188	uint64_t cBlocksAllocMeta;
189	/** Number of blocks allocated for actual cached data. */
190	uint64_t cBlocksAllocData;
191	/** Reserved for future use. */
192	uint8_t au8Reserved[472];
193	} VciBlkMap, *PVciBlkMap;
194	#pragma pack()
195	AssertCompileSize(VciBlkMap, VCI_BLOCK_SIZE);
196
197	/** The magic which identifies a block map. */
198	#define VCI_BLKMAP_MAGIC UINT32_C(0x4b4c4256) /* KLBV */
199	/** Current version. */
200	#define VCI_BLKMAP_VERSION UINT32_C(0x00000001)
201
202	/** Block bitmap entry */
203	typedef uint8_t VciBlkMapEnt;
204
205
206	/*********************************************************************************************************************************
207	* Constants And Macros, Structures and Typedefs *
208	*********************************************************************************************************************************/
209
210	/**
211	* Block range descriptor.
212	*/
213	typedef struct VCIBLKRANGEDESC
214	{
215	/** Previous entry in the list. */
216	struct VCIBLKRANGEDESC *pPrev;
217	/** Next entry in the list. */
218	struct VCIBLKRANGEDESC *pNext;
219	/** Start address of the range. */
220	uint64_t offAddrStart;
221	/** Number of blocks in the range. */
222	uint64_t cBlocks;
223	/** Flag whether the range is free or allocated. */
224	bool fFree;
225	} VCIBLKRANGEDESC, *PVCIBLKRANGEDESC;
226
227	/**
228	* Block map for the cache image - in memory structure.
229	*/
230	typedef struct VCIBLKMAP
231	{
232	/** Number of blocks the map manages. */
233	uint64_t cBlocks;
234	/** Number of blocks allocated for metadata. */
235	uint64_t cBlocksAllocMeta;
236	/** Number of blocks allocated for actual cached data. */
237	uint64_t cBlocksAllocData;
238	/** Number of free blocks. */
239	uint64_t cBlocksFree;
240
241	/** Pointer to the head of the block range list. */
242	PVCIBLKRANGEDESC pRangesHead;
243	/** Pointer to the tail of the block range list. */
244	PVCIBLKRANGEDESC pRangesTail;
245
246	} VCIBLKMAP;
247	/** Pointer to a block map. */
248	typedef VCIBLKMAP *PVCIBLKMAP;
249
250	/**
251	* B+-Tree node header.
252	*/
253	typedef struct VCITREENODE
254	{
255	/** Type of the node (VCI_TREE_NODE_TYPE_). /
256	uint8_t u8Type;
257	/** Block address where the node is stored. */
258	uint64_t u64BlockAddr;
259	/** Pointer to the parent. */
260	struct VCITREENODE *pParent;
261	} VCITREENODE, *PVCITREENODE;
262
263	/**
264	* B+-Tree node pointer.
265	*/
266	typedef struct VCITREENODEPTR
267	{
268	/** Flag whether the node is in memory or still on the disk. */
269	bool fInMemory;
270	/** Type dependent data. */
271	union
272	{
273	/** Pointer to a in memory node. */
274	PVCITREENODE pNode;
275	/** Start block address of the node. */
276	uint64_t offAddrBlockNode;
277	} u;
278	} VCITREENODEPTR, *PVCITREENODEPTR;
279
280	/**
281	* Internal node.
282	*/
283	typedef struct VCINODEINTERNAL
284	{
285	/** First block of cached data the internal node represents. */
286	uint64_t u64BlockOffset;
287	/** Number of blocks the internal node represents. */
288	uint32_t u32Blocks;
289	/** Pointer to the child node. */
290	VCITREENODEPTR PtrChild;
291	} VCINODEINTERNAL, *PVCINODEINTERNAL;
292
293	/**
294	* A in memory internal B+-tree node.
295	*/
296	typedef struct VCITREENODEINT
297	{
298	/** Node core. */
299	VCITREENODE Core;
300	/** Number of used nodes. */
301	unsigned cUsedNodes;
302	/** Array of internal nodes. */
303	VCINODEINTERNAL aIntNodes[VCI_TREE_INTERNAL_NODES_PER_NODE];
304	} VCITREENODEINT, *PVCITREENODEINT;
305
306	/**
307	* A in memory cache extent.
308	*/
309	typedef struct VCICACHEEXTENT
310	{
311	/** First block of cached data the extent represents. */
312	uint64_t u64BlockOffset;
313	/** Number of blocks the extent represents. */
314	uint32_t u32Blocks;
315	/** First block in the image where the data is stored. */
316	uint64_t u64BlockAddr;
317	} VCICACHEEXTENT, *PVCICACHEEXTENT;
318
319	/**
320	* A in memory leaf B+-tree node.
321	*/
322	typedef struct VCITREENODELEAF
323	{
324	/** Node core. */
325	VCITREENODE Core;
326	/** Next leaf node in the list. */
327	struct VCITREENODELEAF *pNext;
328	/** Number of used nodes. */
329	unsigned cUsedNodes;
330	/** The extents in the node. */
331	VCICACHEEXTENT aExtents[VCI_TREE_EXTENTS_PER_NODE];
332	} VCITREENODELEAF, *PVCITREENODELEAF;
333
334	/**
335	* VCI image data structure.
336	*/
337	typedef struct VCICACHE
338	{
339	/** Image name. */
340	const char *pszFilename;
341	/** Storage handle. */
342	PVDIOSTORAGE pStorage;
343
344	/** Pointer to the per-disk VD interface list. */
345	PVDINTERFACE pVDIfsDisk;
346	/** Pointer to the per-image VD interface list. */
347	PVDINTERFACE pVDIfsImage;
348	/** Error interface. */
349	PVDINTERFACEERROR pIfError;
350	/** I/O interface. */
351	PVDINTERFACEIOINT pIfIo;
352
353	/** Open flags passed by VBoxHD layer. */
354	unsigned uOpenFlags;
355	/** Image flags defined during creation or determined during open. */
356	unsigned uImageFlags;
357	/** Total size of the image. */
358	uint64_t cbSize;
359
360	/** Offset of the B+-Tree in the image in bytes. */
361	uint64_t offTreeRoot;
362	/** Pointer to the root node of the B+-Tree. */
363	PVCITREENODE pRoot;
364	/** Offset to the block allocation bitmap in bytes. */
365	uint64_t offBlksBitmap;
366	/** Block map. */
367	PVCIBLKMAP pBlkMap;
368	} VCICACHE, *PVCICACHE;
369
370	/** No block free in bitmap error code. */
371	#define VERR_VCI_NO_BLOCKS_FREE (-65536)
372
373	/** Flags for the block map allocator. */
374	#define VCIBLKMAP_ALLOC_DATA 0
375	#define VCIBLKMAP_ALLOC_META RT_BIT(0)
376	#define VCIBLKMAP_ALLOC_MASK 0x1
377
378
379	/*********************************************************************************************************************************
380	* Static Variables *
381	*********************************************************************************************************************************/
382
383	/** NULL-terminated array of supported file extensions. */
384	static const char *const s_apszVciFileExtensions[] =
385	{
386	"vci",
387	NULL
388	};
389
390
391	/*********************************************************************************************************************************
392	* Internal Functions *
393	*********************************************************************************************************************************/
394
395	/**
396	* Internal. Flush image data to disk.
397	*/
398	static int vciFlushImage(PVCICACHE pCache)
399	{
400	int rc = VINF_SUCCESS;
401
402	if ( pCache->pStorage
403	&& !(pCache->uOpenFlags & VD_OPEN_FLAGS_READONLY))
404	{
405	rc = vdIfIoIntFileFlushSync(pCache->pIfIo, pCache->pStorage);
406	}
407
408	return rc;
409	}
410
411	/**
412	* Internal. Free all allocated space for representing an image except pCache,
413	* and optionally delete the image from disk.
414	*/
415	static int vciFreeImage(PVCICACHE pCache, bool fDelete)
416	{
417	int rc = VINF_SUCCESS;
418
419	/* Freeing a never allocated image (e.g. because the open failed) is
420	* not signalled as an error. After all nothing bad happens. */
421	if (pCache)
422	{
423	if (pCache->pStorage)
424	{
425	/* No point updating the file that is deleted anyway. */
426	if (!fDelete)
427	vciFlushImage(pCache);
428
429	vdIfIoIntFileClose(pCache->pIfIo, pCache->pStorage);
430	pCache->pStorage = NULL;
431	}
432
433	if (fDelete && pCache->pszFilename)
434	vdIfIoIntFileDelete(pCache->pIfIo, pCache->pszFilename);
435	}
436
437	LogFlowFunc(("returns %Rrc\n", rc));
438	return rc;
439	}
440
441	/**
442	* Creates a new block map which can manage the given number of blocks.
443	*
444	* The size of the bitmap is aligned to the VCI block size.
445	*
446	* @returns VBox status code.
447	* @param cBlocks The number of blocks the bitmap can manage.
448	* @param ppBlkMap Where to store the pointer to the block bitmap.
449	* @param pcBlkMap Where to store the size of the block bitmap in blocks
450	* needed on the disk.
451	*/
452	static int vciBlkMapCreate(uint64_t cBlocks, PVCIBLKMAP ppBlkMap, uint32_t pcBlkMap)
453	{
454	int rc = VINF_SUCCESS;
455	uint32_t cbBlkMap = RT_ALIGN_Z(cBlocks / sizeof(VciBlkMapEnt) / 8, VCI_BLOCK_SIZE);
456	PVCIBLKMAP pBlkMap = (PVCIBLKMAP)RTMemAllocZ(sizeof(VCIBLKMAP));
457	PVCIBLKRANGEDESC pFree = (PVCIBLKRANGEDESC)RTMemAllocZ(sizeof(VCIBLKRANGEDESC));
458
459	LogFlowFunc(("cBlocks=%u ppBlkMap=%#p pcBlkMap=%#p\n", cBlocks, ppBlkMap, pcBlkMap));
460
461	if (pBlkMap && pFree)
462	{
463	pBlkMap->cBlocks = cBlocks;
464	pBlkMap->cBlocksAllocMeta = 0;
465	pBlkMap->cBlocksAllocData = 0;
466	pBlkMap->cBlocksFree = cBlocks;
467
468	pFree->pPrev = NULL;
469	pFree->pNext = NULL;
470	pFree->offAddrStart = 0;
471	pFree->cBlocks = cBlocks;
472	pFree->fFree = true;
473
474	pBlkMap->pRangesHead = pFree;
475	pBlkMap->pRangesTail = pFree;
476
477	Assert(!((cbBlkMap + sizeof(VciBlkMap)) % VCI_BLOCK_SIZE));
478	*ppBlkMap = pBlkMap;
479	*pcBlkMap = VCI_BYTE2BLOCK(cbBlkMap + sizeof(VciBlkMap));
480	}
481	else
482	{
483	if (pBlkMap)
484	RTMemFree(pBlkMap);
485	if (pFree)
486	RTMemFree(pFree);
487
488	rc = VERR_NO_MEMORY;
489	}
490
491	LogFlowFunc(("returns rc=%Rrc cBlkMap=%u\n", rc, *pcBlkMap));
492	return rc;
493	}
494
495	#if 0 /** @todo unsued vciBlkMapDestroy */
496	/**
497	* Frees a block map.
498	*
499	* @returns nothing.
500	* @param pBlkMap The block bitmap to destroy.
501	*/
502	static void vciBlkMapDestroy(PVCIBLKMAP pBlkMap)
503	{
504	LogFlowFunc(("pBlkMap=%#p\n", pBlkMap));
505
506	PVCIBLKRANGEDESC pRangeCur = pBlkMap->pRangesHead;
507
508	while (pRangeCur)
509	{
510	PVCIBLKRANGEDESC pTmp = pRangeCur;
511
512	RTMemFree(pTmp);
513
514	pRangeCur = pRangeCur->pNext;
515	}
516
517	RTMemFree(pBlkMap);
518
519	LogFlowFunc(("returns\n"));
520	}
521	#endif
522
523	/**
524	* Loads the block map from the specified medium and creates all necessary
525	* in memory structures to manage used and free blocks.
526	*
527	* @returns VBox status code.
528	* @param pStorage Storage handle to read the block bitmap from.
529	* @param offBlkMap Start of the block bitmap in blocks.
530	* @param cBlkMap Size of the block bitmap on the disk in blocks.
531	* @param ppBlkMap Where to store the block bitmap on success.
532	*/
533	static int vciBlkMapLoad(PVCICACHE pStorage, uint64_t offBlkMap, uint32_t cBlkMap, PVCIBLKMAP *ppBlkMap)
534	{
535	int rc = VINF_SUCCESS;
536	VciBlkMap BlkMap;
537
538	LogFlowFunc(("pStorage=%#p offBlkMap=%llu cBlkMap=%u ppBlkMap=%#p\n",
539	pStorage, offBlkMap, cBlkMap, ppBlkMap));
540
541	if (cBlkMap >= VCI_BYTE2BLOCK(sizeof(VciBlkMap)))
542	{
543	cBlkMap -= VCI_BYTE2BLOCK(sizeof(VciBlkMap));
544
545	rc = vdIfIoIntFileReadSync(pStorage->pIfIo, pStorage->pStorage, offBlkMap,
546	&BlkMap, VCI_BYTE2BLOCK(sizeof(VciBlkMap)));
547	if (RT_SUCCESS(rc))
548	{
549	offBlkMap += VCI_BYTE2BLOCK(sizeof(VciBlkMap));
550
551	BlkMap.u32Magic = RT_LE2H_U32(BlkMap.u32Magic);
552	BlkMap.u32Version = RT_LE2H_U32(BlkMap.u32Version);
553	BlkMap.cBlocks = RT_LE2H_U32(BlkMap.cBlocks);
554	BlkMap.cBlocksFree = RT_LE2H_U32(BlkMap.cBlocksFree);
555	BlkMap.cBlocksAllocMeta = RT_LE2H_U32(BlkMap.cBlocksAllocMeta);
556	BlkMap.cBlocksAllocData = RT_LE2H_U32(BlkMap.cBlocksAllocData);
557
558	if ( BlkMap.u32Magic == VCI_BLKMAP_MAGIC
559	&& BlkMap.u32Version == VCI_BLKMAP_VERSION
560	&& BlkMap.cBlocks == BlkMap.cBlocksFree + BlkMap.cBlocksAllocMeta + BlkMap.cBlocksAllocData
561	&& VCI_BYTE2BLOCK(BlkMap.cBlocks / 8) == cBlkMap)
562	{
563	PVCIBLKMAP pBlkMap = (PVCIBLKMAP)RTMemAllocZ(sizeof(VCIBLKMAP));
564	if (pBlkMap)
565	{
566	pBlkMap->cBlocks = BlkMap.cBlocks;
567	pBlkMap->cBlocksFree = BlkMap.cBlocksFree;
568	pBlkMap->cBlocksAllocMeta = BlkMap.cBlocksAllocMeta;
569	pBlkMap->cBlocksAllocData = BlkMap.cBlocksAllocData;
570
571	/* Load the bitmap and construct the range list. */
572	PVCIBLKRANGEDESC pRangeCur = (PVCIBLKRANGEDESC)RTMemAllocZ(sizeof(VCIBLKRANGEDESC));
573
574	if (pRangeCur)
575	{
576	uint8_t abBitmapBuffer[16 * _1K];
577	uint32_t cBlocksRead = 0;
578	uint64_t cBlocksLeft = VCI_BYTE2BLOCK(pBlkMap->cBlocks / 8);
579
580	cBlocksRead = RT_MIN(VCI_BYTE2BLOCK(sizeof(abBitmapBuffer)), cBlocksLeft);
581	rc = vdIfIoIntFileReadSync(pStorage->pIfIo, pStorage->pStorage,
582	offBlkMap, abBitmapBuffer,
583	cBlocksRead);
584
585	if (RT_SUCCESS(rc))
586	{
587	pRangeCur->fFree = !(abBitmapBuffer[0] & 0x01);
588	pRangeCur->offAddrStart = 0;
589	pRangeCur->cBlocks = 0;
590	pRangeCur->pNext = NULL;
591	pRangeCur->pPrev = NULL;
592	pBlkMap->pRangesHead = pRangeCur;
593	pBlkMap->pRangesTail = pRangeCur;
594	}
595	else
596	RTMemFree(pRangeCur);
597
598	while ( RT_SUCCESS(rc)
599	&& cBlocksLeft)
600	{
601	int iBit = 0;
602	uint32_t cBits = VCI_BLOCK2BYTE(cBlocksRead) * 8;
603	uint32_t iBitPrev = 0xffffffff;
604
605	while (cBits)
606	{
607	if (pRangeCur->fFree)
608	{
609	/* Check for the first set bit. */
610	iBit = ASMBitNextSet(abBitmapBuffer, cBits, iBitPrev);
611	}
612	else
613	{
614	/* Check for the first free bit. */
615	iBit = ASMBitNextClear(abBitmapBuffer, cBits, iBitPrev);
616	}
617
618	if (iBit == -1)
619	{
620	/* No change. */
621	pRangeCur->cBlocks += cBits;
622	cBits = 0;
623	}
624	else
625	{
626	Assert((uint32_t)iBit < cBits);
627	pRangeCur->cBlocks += iBit;
628
629	/* Create a new range descriptor. */
630	PVCIBLKRANGEDESC pRangeNew = (PVCIBLKRANGEDESC)RTMemAllocZ(sizeof(VCIBLKRANGEDESC));
631	if (!pRangeNew)
632	{
633	rc = VERR_NO_MEMORY;
634	break;
635	}
636
637	pRangeNew->fFree = !pRangeCur->fFree;
638	pRangeNew->offAddrStart = pRangeCur->offAddrStart + pRangeCur->cBlocks;
639	pRangeNew->cBlocks = 0;
640	pRangeNew->pPrev = pRangeCur;
641	pRangeCur->pNext = pRangeNew;
642	pBlkMap->pRangesTail = pRangeNew;
643	pRangeCur = pRangeNew;
644	cBits -= iBit;
645	iBitPrev = iBit;
646	}
647	}
648
649	cBlocksLeft -= cBlocksRead;
650	offBlkMap += cBlocksRead;
651
652	if ( RT_SUCCESS(rc)
653	&& cBlocksLeft)
654	{
655	/* Read next chunk. */
656	cBlocksRead = RT_MIN(VCI_BYTE2BLOCK(sizeof(abBitmapBuffer)), cBlocksLeft);
657	rc = vdIfIoIntFileReadSync(pStorage->pIfIo, pStorage->pStorage,
658	offBlkMap, abBitmapBuffer, cBlocksRead);
659	}
660	}
661	}
662	else
663	rc = VERR_NO_MEMORY;
664
665	if (RT_SUCCESS(rc))
666	{
667	*ppBlkMap = pBlkMap;
668	LogFlowFunc(("return success\n"));
669	return VINF_SUCCESS;
670	}
671
672	RTMemFree(pBlkMap);
673	}
674	else
675	rc = VERR_NO_MEMORY;
676	}
677	else
678	rc = VERR_VD_GEN_INVALID_HEADER;
679	}
680	else
681	rc = VERR_VD_GEN_INVALID_HEADER;
682	}
683	else
684	rc = VERR_VD_GEN_INVALID_HEADER;
685
686	LogFlowFunc(("returns rc=%Rrc\n", rc));
687	return rc;
688	}
689
690	/**
691	* Saves the block map in the cache image. All necessary on disk structures
692	* are written.
693	*
694	* @returns VBox status code.
695	* @param pBlkMap The block bitmap to save.
696	* @param pStorage Where the block bitmap should be written to.
697	* @param offBlkMap Start of the block bitmap in blocks.
698	* @param cBlkMap Size of the block bitmap on the disk in blocks.
699	*/
700	static int vciBlkMapSave(PVCIBLKMAP pBlkMap, PVCICACHE pStorage, uint64_t offBlkMap, uint32_t cBlkMap)
701	{
702	int rc = VINF_SUCCESS;
703	VciBlkMap BlkMap;
704
705	LogFlowFunc(("pBlkMap=%#p pStorage=%#p offBlkMap=%llu cBlkMap=%u\n",
706	pBlkMap, pStorage, offBlkMap, cBlkMap));
707
708	/* Make sure the number of blocks allocated for us match our expectations. */
709	if (VCI_BYTE2BLOCK(pBlkMap->cBlocks / 8) + VCI_BYTE2BLOCK(sizeof(VciBlkMap)) == cBlkMap)
710	{
711	/* Setup the header */
712	memset(&BlkMap, 0, sizeof(VciBlkMap));
713
714	BlkMap.u32Magic = RT_H2LE_U32(VCI_BLKMAP_MAGIC);
715	BlkMap.u32Version = RT_H2LE_U32(VCI_BLKMAP_VERSION);
716	BlkMap.cBlocks = RT_H2LE_U32(pBlkMap->cBlocks);
717	BlkMap.cBlocksFree = RT_H2LE_U32(pBlkMap->cBlocksFree);
718	BlkMap.cBlocksAllocMeta = RT_H2LE_U32(pBlkMap->cBlocksAllocMeta);
719	BlkMap.cBlocksAllocData = RT_H2LE_U32(pBlkMap->cBlocksAllocData);
720
721	rc = vdIfIoIntFileWriteSync(pStorage->pIfIo, pStorage->pStorage, offBlkMap,
722	&BlkMap, VCI_BYTE2BLOCK(sizeof(VciBlkMap)));
723	if (RT_SUCCESS(rc))
724	{
725	uint8_t abBitmapBuffer[16*_1K];
726	unsigned iBit = 0;
727	PVCIBLKRANGEDESC pCur = pBlkMap->pRangesHead;
728
729	offBlkMap += VCI_BYTE2BLOCK(sizeof(VciBlkMap));
730
731	/* Write the descriptor ranges. */
732	while (pCur)
733	{
734	uint64_t cBlocks = pCur->cBlocks;
735
736	while (cBlocks)
737	{
738	uint64_t cBlocksMax = RT_MIN(cBlocks, sizeof(abBitmapBuffer) * 8 - iBit);
739
740	if (pCur->fFree)
741	ASMBitClearRange(abBitmapBuffer, iBit, iBit + cBlocksMax);
742	else
743	ASMBitSetRange(abBitmapBuffer, iBit, iBit + cBlocksMax);
744
745	iBit += cBlocksMax;
746	cBlocks -= cBlocksMax;
747
748	if (iBit == sizeof(abBitmapBuffer) * 8)
749	{
750	/* Buffer is full, write to file and reset. */
751	rc = vdIfIoIntFileWriteSync(pStorage->pIfIo, pStorage->pStorage,
752	offBlkMap, abBitmapBuffer,
753	VCI_BYTE2BLOCK(sizeof(abBitmapBuffer)));
754	if (RT_FAILURE(rc))
755	break;
756
757	offBlkMap += VCI_BYTE2BLOCK(sizeof(abBitmapBuffer));
758	iBit = 0;
759	}
760	}
761
762	pCur = pCur->pNext;
763	}
764
765	Assert(iBit % 8 == 0);
766
767	if (RT_SUCCESS(rc) && iBit)
768	rc = vdIfIoIntFileWriteSync(pStorage->pIfIo, pStorage->pStorage,
769	offBlkMap, abBitmapBuffer, VCI_BYTE2BLOCK(iBit / 8));
770	}
771	}
772	else
773	rc = VERR_INTERNAL_ERROR; /** @todo Better error code. */
774
775	LogFlowFunc(("returns rc=%Rrc\n", rc));
776	return rc;
777	}
778
779	#if 0 /* unused */
780	/**
781	* Finds the range block describing the given block address.
782	*
783	* @returns Pointer to the block range descriptor or NULL if none could be found.
784	* @param pBlkMap The block bitmap to search on.
785	* @param offBlockAddr The block address to search for.
786	*/
787	static PVCIBLKRANGEDESC vciBlkMapFindByBlock(PVCIBLKMAP pBlkMap, uint64_t offBlockAddr)
788	{
789	PVCIBLKRANGEDESC pBlk = pBlkMap->pRangesHead;
790
791	while ( pBlk
792	&& pBlk->offAddrStart < offBlockAddr)
793	pBlk = pBlk->pNext;
794
795	return pBlk;
796	}
797	#endif
798
799	/**
800	* Allocates the given number of blocks in the bitmap and returns the start block address.
801	*
802	* @returns VBox status code.
803	* @param pBlkMap The block bitmap to allocate the blocks from.
804	* @param cBlocks How many blocks to allocate.
805	* @param fFlags Allocation flags, comgination of VCIBLKMAP_ALLOC_*.
806	* @param poffBlockAddr Where to store the start address of the allocated region.
807	*/
808	static int vciBlkMapAllocate(PVCIBLKMAP pBlkMap, uint32_t cBlocks, uint32_t fFlags,
809	uint64_t *poffBlockAddr)
810	{
811	PVCIBLKRANGEDESC pBestFit = NULL;
812	PVCIBLKRANGEDESC pCur = NULL;
813	int rc = VINF_SUCCESS;
814
815	LogFlowFunc(("pBlkMap=%#p cBlocks=%u poffBlockAddr=%#p\n",
816	pBlkMap, cBlocks, poffBlockAddr));
817
818	pCur = pBlkMap->pRangesHead;
819
820	while (pCur)
821	{
822	if ( pCur->fFree
823	&& pCur->cBlocks >= cBlocks)
824	{
825	if ( !pBestFit
826	\|\| pCur->cBlocks < pBestFit->cBlocks)
827	{
828	pBestFit = pCur;
829	/* Stop searching if the size is matching exactly. */
830	if (pBestFit->cBlocks == cBlocks)
831	break;
832	}
833	}
834	pCur = pCur->pNext;
835	}
836
837	Assert(!pBestFit \|\| pBestFit->fFree);
838
839	if (pBestFit)
840	{
841	pBestFit->fFree = false;
842
843	if (pBestFit->cBlocks > cBlocks)
844	{
845	/* Create a new free block. */
846	PVCIBLKRANGEDESC pFree = (PVCIBLKRANGEDESC)RTMemAllocZ(sizeof(VCIBLKRANGEDESC));
847
848	if (pFree)
849	{
850	pFree->fFree = true;
851	pFree->cBlocks = pBestFit->cBlocks - cBlocks;
852	pBestFit->cBlocks -= pFree->cBlocks;
853	pFree->offAddrStart = pBestFit->offAddrStart + cBlocks;
854
855	/* Link into the list. */
856	pFree->pNext = pBestFit->pNext;
857	pBestFit->pNext = pFree;
858	pFree->pPrev = pBestFit;
859	if (!pFree->pNext)
860	pBlkMap->pRangesTail = pFree;
861
862	*poffBlockAddr = pBestFit->offAddrStart;
863	}
864	else
865	{
866	rc = VERR_NO_MEMORY;
867	pBestFit->fFree = true;
868	}
869	}
870	}
871	else
872	rc = VERR_VCI_NO_BLOCKS_FREE;
873
874	if (RT_SUCCESS(rc))
875	{
876	if ((fFlags & VCIBLKMAP_ALLOC_MASK) == VCIBLKMAP_ALLOC_DATA)
877	pBlkMap->cBlocksAllocMeta += cBlocks;
878	else
879	pBlkMap->cBlocksAllocData += cBlocks;
880
881	pBlkMap->cBlocksFree -= cBlocks;
882	}
883
884	LogFlowFunc(("returns rc=%Rrc offBlockAddr=%llu\n", rc, *poffBlockAddr));
885	return rc;
886	}
887
888	#if 0 /* unused */
889	/**
890	* Try to extend the space of an already allocated block.
891	*
892	* @returns VBox status code.
893	* @param pBlkMap The block bitmap to allocate the blocks from.
894	* @param cBlocksNew How many blocks the extended block should have.
895	* @param offBlockAddrOld The start address of the block to reallocate.
896	* @param poffBlockAddr Where to store the start address of the allocated region.
897	*/
898	static int vciBlkMapRealloc(PVCIBLKMAP pBlkMap, uint32_t cBlocksNew, uint64_t offBlockAddrOld,
899	uint64_t *poffBlockAddr)
900	{
901	int rc = VINF_SUCCESS;
902
903	LogFlowFunc(("pBlkMap=%#p cBlocksNew=%u offBlockAddrOld=%llu poffBlockAddr=%#p\n",
904	pBlkMap, cBlocksNew, offBlockAddrOld, poffBlockAddr));
905
906	AssertMsgFailed(("Implement\n"));
907	RT_NOREF4(pBlkMap, cBlocksNew, offBlockAddrOld, poffBlockAddr);
908
909	LogFlowFunc(("returns rc=%Rrc offBlockAddr=%llu\n", rc, *poffBlockAddr));
910	return rc;
911	}
912	#endif /* unused */
913
914	#if 0 /* unused */
915	/**
916	* Frees a range of blocks.
917	*
918	* @returns nothing.
919	* @param pBlkMap The block bitmap.
920	* @param offBlockAddr Address of the first block to free.
921	* @param cBlocks How many blocks to free.
922	* @param fFlags Allocation flags, comgination of VCIBLKMAP_ALLOC_*.
923	*/
924	static void vciBlkMapFree(PVCIBLKMAP pBlkMap, uint64_t offBlockAddr, uint32_t cBlocks,
925	uint32_t fFlags)
926	{
927	PVCIBLKRANGEDESC pBlk;
928
929	LogFlowFunc(("pBlkMap=%#p offBlockAddr=%llu cBlocks=%u\n",
930	pBlkMap, offBlockAddr, cBlocks));
931
932	while (cBlocks)
933	{
934	pBlk = vciBlkMapFindByBlock(pBlkMap, offBlockAddr);
935	AssertPtr(pBlk);
936
937	/* Easy case, the whole block is freed. */
938	if ( pBlk->offAddrStart == offBlockAddr
939	&& pBlk->cBlocks <= cBlocks)
940	{
941	pBlk->fFree = true;
942	cBlocks -= pBlk->cBlocks;
943	offBlockAddr += pBlk->cBlocks;
944
945	/* Check if it is possible to merge free blocks. */
946	if ( pBlk->pPrev
947	&& pBlk->pPrev->fFree)
948	{
949	PVCIBLKRANGEDESC pBlkPrev = pBlk->pPrev;
950
951	Assert(pBlkPrev->offAddrStart + pBlkPrev->cBlocks == pBlk->offAddrStart);
952	pBlkPrev->cBlocks += pBlk->cBlocks;
953	pBlkPrev->pNext = pBlk->pNext;
954	if (pBlk->pNext)
955	pBlk->pNext->pPrev = pBlkPrev;
956	else
957	pBlkMap->pRangesTail = pBlkPrev;
958
959	RTMemFree(pBlk);
960	pBlk = pBlkPrev;
961	}
962
963	/* Now the one to the right. */
964	if ( pBlk->pNext
965	&& pBlk->pNext->fFree)
966	{
967	PVCIBLKRANGEDESC pBlkNext = pBlk->pNext;
968
969	Assert(pBlk->offAddrStart + pBlk->cBlocks == pBlkNext->offAddrStart);
970	pBlk->cBlocks += pBlkNext->cBlocks;
971	pBlk->pNext = pBlkNext->pNext;
972	if (pBlkNext->pNext)
973	pBlkNext->pNext->pPrev = pBlk;
974	else
975	pBlkMap->pRangesTail = pBlk;
976
977	RTMemFree(pBlkNext);
978	}
979	}
980	else
981	{
982	/* The block is intersecting. */
983	AssertMsgFailed(("TODO\n"));
984	}
985	}
986
987	if ((fFlags & VCIBLKMAP_ALLOC_MASK) == VCIBLKMAP_ALLOC_DATA)
988	pBlkMap->cBlocksAllocMeta -= cBlocks;
989	else
990	pBlkMap->cBlocksAllocData -= cBlocks;
991
992	pBlkMap->cBlocksFree += cBlocks;
993
994	LogFlowFunc(("returns\n"));
995	}
996	#endif /* unused */
997
998	/**
999	* Converts a tree node from the image to the in memory structure.
1000	*
1001	* @returns Pointer to the in memory tree node.
1002	* @param offBlockAddrNode Block address of the node.
1003	* @param pNodeImage Pointer to the image representation of the node.
1004	*/
1005	static PVCITREENODE vciTreeNodeImage2Host(uint64_t offBlockAddrNode, PVciTreeNode pNodeImage)
1006	{
1007	PVCITREENODE pNode = NULL;
1008
1009	if (pNodeImage->u8Type == VCI_TREE_NODE_TYPE_LEAF)
1010	{
1011	PVCITREENODELEAF pLeaf = (PVCITREENODELEAF)RTMemAllocZ(sizeof(VCITREENODELEAF));
1012
1013	if (pLeaf)
1014	{
1015	PVciCacheExtent pExtent = (PVciCacheExtent)&pNodeImage->au8Data[0];
1016
1017	pLeaf->Core.u8Type = VCI_TREE_NODE_TYPE_LEAF;
1018
1019	for (unsigned idx = 0; idx < RT_ELEMENTS(pLeaf->aExtents); idx++)
1020	{
1021	pLeaf->aExtents[idx].u64BlockOffset = RT_LE2H_U64(pExtent->u64BlockOffset);
1022	pLeaf->aExtents[idx].u32Blocks = RT_LE2H_U32(pExtent->u32Blocks);
1023	pLeaf->aExtents[idx].u64BlockAddr = RT_LE2H_U64(pExtent->u64BlockAddr);
1024	pExtent++;
1025
1026	if ( pLeaf->aExtents[idx].u32Blocks
1027	&& pLeaf->aExtents[idx].u64BlockAddr)
1028	pLeaf->cUsedNodes++;
1029	}
1030
1031	pNode = &pLeaf->Core;
1032	}
1033	}
1034	else if (pNodeImage->u8Type == VCI_TREE_NODE_TYPE_INTERNAL)
1035	{
1036	PVCITREENODEINT pInt = (PVCITREENODEINT)RTMemAllocZ(sizeof(VCITREENODEINT));
1037
1038	if (pInt)
1039	{
1040	PVciTreeNodeInternal pIntImage = (PVciTreeNodeInternal)&pNodeImage->au8Data[0];
1041
1042	pInt->Core.u8Type = VCI_TREE_NODE_TYPE_INTERNAL;
1043
1044	for (unsigned idx = 0; idx < RT_ELEMENTS(pInt->aIntNodes); idx++)
1045	{
1046	pInt->aIntNodes[idx].u64BlockOffset = RT_LE2H_U64(pIntImage->u64BlockOffset);
1047	pInt->aIntNodes[idx].u32Blocks = RT_LE2H_U32(pIntImage->u32Blocks);
1048	pInt->aIntNodes[idx].PtrChild.fInMemory = false;
1049	pInt->aIntNodes[idx].PtrChild.u.offAddrBlockNode = RT_LE2H_U64(pIntImage->u64ChildAddr);
1050	pIntImage++;
1051
1052	if ( pInt->aIntNodes[idx].u32Blocks
1053	&& pInt->aIntNodes[idx].PtrChild.u.offAddrBlockNode)
1054	pInt->cUsedNodes++;
1055	}
1056
1057	pNode = &pInt->Core;
1058	}
1059	}
1060	else
1061	AssertMsgFailed(("Invalid node type %d\n", pNodeImage->u8Type));
1062
1063	if (pNode)
1064	pNode->u64BlockAddr = offBlockAddrNode;
1065
1066	return pNode;
1067	}
1068
1069	/**
1070	* Looks up the cache extent for the given virtual block address.
1071	*
1072	* @returns Pointer to the cache extent or NULL if none could be found.
1073	* @param pCache The cache image instance.
1074	* @param offBlockOffset The block offset to search for.
1075	* @param ppNextBestFit Where to store the pointer to the next best fit
1076	* cache extent above offBlockOffset if existing. - Optional
1077	* This is always filled if possible even if the function returns NULL.
1078	*/
1079	static PVCICACHEEXTENT vciCacheExtentLookup(PVCICACHE pCache, uint64_t offBlockOffset,
1080	PVCICACHEEXTENT *ppNextBestFit)
1081	{
1082	int rc = VINF_SUCCESS;
1083	PVCICACHEEXTENT pExtent = NULL;
1084	PVCITREENODE pNodeCur = pCache->pRoot;
1085
1086	while ( RT_SUCCESS(rc)
1087	&& pNodeCur
1088	&& pNodeCur->u8Type != VCI_TREE_NODE_TYPE_LEAF)
1089	{
1090	PVCITREENODEINT pNodeInt = (PVCITREENODEINT)pNodeCur;
1091
1092	Assert(pNodeCur->u8Type == VCI_TREE_NODE_TYPE_INTERNAL);
1093
1094	/* Search for the correct internal node. */
1095	unsigned idxMin = 0;
1096	unsigned idxMax = pNodeInt->cUsedNodes;
1097	unsigned idxCur = pNodeInt->cUsedNodes / 2;
1098
1099	while (idxMin < idxMax)
1100	{
1101	PVCINODEINTERNAL pInt = &pNodeInt->aIntNodes[idxCur];
1102
1103	/* Determine the search direction. */
1104	if (offBlockOffset < pInt->u64BlockOffset)
1105	{
1106	/* Search left from the current extent. */
1107	idxMax = idxCur;
1108	}
1109	else if (offBlockOffset >= pInt->u64BlockOffset + pInt->u32Blocks)
1110	{
1111	/* Search right from the current extent. */
1112	idxMin = idxCur;
1113	}
1114	else
1115	{
1116	/* The block lies in the node, stop searching. */
1117	if (pInt->PtrChild.fInMemory)
1118	pNodeCur = pInt->PtrChild.u.pNode;
1119	else
1120	{
1121	PVCITREENODE pNodeNew;
1122	VciTreeNode NodeTree;
1123
1124	/* Read from disk and add to the tree. */
1125	rc = vdIfIoIntFileReadSync(pCache->pIfIo, pCache->pStorage,
1126	VCI_BLOCK2BYTE(pInt->PtrChild.u.offAddrBlockNode),
1127	&NodeTree, sizeof(NodeTree));
1128	AssertRC(rc);
1129
1130	pNodeNew = vciTreeNodeImage2Host(pInt->PtrChild.u.offAddrBlockNode, &NodeTree);
1131	if (pNodeNew)
1132	{
1133	/* Link to the parent. */
1134	pInt->PtrChild.fInMemory = true;
1135	pInt->PtrChild.u.pNode = pNodeNew;
1136	pNodeNew->pParent = pNodeCur;
1137	pNodeCur = pNodeNew;
1138	}
1139	else
1140	rc = VERR_NO_MEMORY;
1141	}
1142	break;
1143	}
1144
1145	idxCur = idxMin + (idxMax - idxMin) / 2;
1146	}
1147	}
1148
1149	if ( RT_SUCCESS(rc)
1150	&& pNodeCur)
1151	{
1152	PVCITREENODELEAF pLeaf = (PVCITREENODELEAF)pNodeCur;
1153	Assert(pNodeCur->u8Type == VCI_TREE_NODE_TYPE_LEAF);
1154
1155	/* Search the range. */
1156	unsigned idxMin = 0;
1157	unsigned idxMax = pLeaf->cUsedNodes;
1158	unsigned idxCur = pLeaf->cUsedNodes / 2;
1159
1160	while (idxMin < idxMax)
1161	{
1162	PVCICACHEEXTENT pExtentCur = &pLeaf->aExtents[idxCur];
1163
1164	/* Determine the search direction. */
1165	if (offBlockOffset < pExtentCur->u64BlockOffset)
1166	{
1167	/* Search left from the current extent. */
1168	idxMax = idxCur;
1169	}
1170	else if (offBlockOffset >= pExtentCur->u64BlockOffset + pExtentCur->u32Blocks)
1171	{
1172	/* Search right from the current extent. */
1173	idxMin = idxCur;
1174	}
1175	else
1176	{
1177	/* We found the extent, stop searching. */
1178	pExtent = pExtentCur;
1179	break;
1180	}
1181
1182	idxCur = idxMin + (idxMax - idxMin) / 2;
1183	}
1184
1185	/* Get the next best fit extent if it exists. */
1186	if (ppNextBestFit)
1187	{
1188	if (idxCur < pLeaf->cUsedNodes - 1)
1189	*ppNextBestFit = &pLeaf->aExtents[idxCur + 1];
1190	else
1191	{
1192	/*
1193	* Go up the tree and find the best extent
1194	* in the leftmost tree of the child subtree to the right.
1195	*/
1196	PVCITREENODEINT pInt = (PVCITREENODEINT)pLeaf->Core.pParent;
1197
1198	while (pInt)
1199	{
1200
1201	}
1202	}
1203	}
1204	}
1205
1206	return pExtent;
1207	}
1208
1209	/**
1210	* Internal: Open an image, constructing all necessary data structures.
1211	*/
1212	static int vciOpenImage(PVCICACHE pCache, unsigned uOpenFlags)
1213	{
1214	VciHdr Hdr;
1215	uint64_t cbFile;
1216	int rc;
1217
1218	pCache->uOpenFlags = uOpenFlags;
1219
1220	pCache->pIfError = VDIfErrorGet(pCache->pVDIfsDisk);
1221	pCache->pIfIo = VDIfIoIntGet(pCache->pVDIfsImage);
1222	AssertPtrReturn(pCache->pIfIo, VERR_INVALID_PARAMETER);
1223
1224	/*
1225	* Open the image.
1226	*/
1227	rc = vdIfIoIntFileOpen(pCache->pIfIo, pCache->pszFilename,
1228	VDOpenFlagsToFileOpenFlags(uOpenFlags,
1229	false /* fCreate */),
1230	&pCache->pStorage);
1231	if (RT_FAILURE(rc))
1232	{
1233	/* Do NOT signal an appropriate error here, as the VD layer has the
1234	* choice of retrying the open if it failed. */
1235	goto out;
1236	}
1237
1238	rc = vdIfIoIntFileGetSize(pCache->pIfIo, pCache->pStorage, &cbFile);
1239	if (RT_FAILURE(rc) \|\| cbFile < sizeof(VciHdr))
1240	{
1241	rc = VERR_VD_GEN_INVALID_HEADER;
1242	goto out;
1243	}
1244
1245	rc = vdIfIoIntFileReadSync(pCache->pIfIo, pCache->pStorage, 0, &Hdr,
1246	VCI_BYTE2BLOCK(sizeof(Hdr)));
1247	if (RT_FAILURE(rc))
1248	{
1249	rc = VERR_VD_GEN_INVALID_HEADER;
1250	goto out;
1251	}
1252
1253	Hdr.u32Signature = RT_LE2H_U32(Hdr.u32Signature);
1254	Hdr.u32Version = RT_LE2H_U32(Hdr.u32Version);
1255	Hdr.cBlocksCache = RT_LE2H_U64(Hdr.cBlocksCache);
1256	Hdr.u32CacheType = RT_LE2H_U32(Hdr.u32CacheType);
1257	Hdr.offTreeRoot = RT_LE2H_U64(Hdr.offTreeRoot);
1258	Hdr.offBlkMap = RT_LE2H_U64(Hdr.offBlkMap);
1259	Hdr.cBlkMap = RT_LE2H_U32(Hdr.cBlkMap);
1260
1261	if ( Hdr.u32Signature == VCI_HDR_SIGNATURE
1262	&& Hdr.u32Version == VCI_HDR_VERSION)
1263	{
1264	pCache->offTreeRoot = Hdr.offTreeRoot;
1265	pCache->offBlksBitmap = Hdr.offBlkMap;
1266
1267	/* Load the block map. */
1268	rc = vciBlkMapLoad(pCache, pCache->offBlksBitmap, Hdr.cBlkMap, &pCache->pBlkMap);
1269	if (RT_SUCCESS(rc))
1270	{
1271	/* Load the first tree node. */
1272	VciTreeNode RootNode;
1273
1274	rc = vdIfIoIntFileReadSync(pCache->pIfIo, pCache->pStorage,
1275	pCache->offTreeRoot, &RootNode,
1276	VCI_BYTE2BLOCK(sizeof(VciTreeNode)));
1277	if (RT_SUCCESS(rc))
1278	{
1279	pCache->pRoot = vciTreeNodeImage2Host(pCache->offTreeRoot, &RootNode);
1280	if (!pCache->pRoot)
1281	rc = VERR_NO_MEMORY;
1282	}
1283	}
1284	}
1285	else
1286	rc = VERR_VD_GEN_INVALID_HEADER;
1287
1288	out:
1289	if (RT_FAILURE(rc))
1290	vciFreeImage(pCache, false);
1291	return rc;
1292	}
1293
1294	/**
1295	* Internal: Create a vci image.
1296	*/
1297	static int vciCreateImage(PVCICACHE pCache, uint64_t cbSize,
1298	unsigned uImageFlags, const char *pszComment,
1299	unsigned uOpenFlags, PFNVDPROGRESS pfnProgress,
1300	void *pvUser, unsigned uPercentStart,
1301	unsigned uPercentSpan)
1302	{
1303	RT_NOREF1(pszComment);
1304	VciHdr Hdr;
1305	VciTreeNode NodeRoot;
1306	int rc;
1307	uint64_t cBlocks = cbSize / VCI_BLOCK_SIZE; /* Size of the cache in blocks. */
1308
1309	pCache->uImageFlags = uImageFlags;
1310	pCache->uOpenFlags = uOpenFlags & ~VD_OPEN_FLAGS_READONLY;
1311
1312	pCache->pIfError = VDIfErrorGet(pCache->pVDIfsDisk);
1313	pCache->pIfIo = VDIfIoIntGet(pCache->pVDIfsImage);
1314	AssertPtrReturn(pCache->pIfIo, VERR_INVALID_PARAMETER);
1315
1316	if (uImageFlags & VD_IMAGE_FLAGS_DIFF)
1317	{
1318	rc = vdIfError(pCache->pIfError, VERR_VD_RAW_INVALID_TYPE, RT_SRC_POS, N_("VCI: cannot create diff image '%s'"), pCache->pszFilename);
1319	return rc;
1320	}
1321
1322	do
1323	{
1324	/* Create image file. */
1325	rc = vdIfIoIntFileOpen(pCache->pIfIo, pCache->pszFilename,
1326	VDOpenFlagsToFileOpenFlags(uOpenFlags & ~VD_OPEN_FLAGS_READONLY,
1327	true /* fCreate */),
1328	&pCache->pStorage);
1329	if (RT_FAILURE(rc))
1330	{
1331	rc = vdIfError(pCache->pIfError, rc, RT_SRC_POS, N_("VCI: cannot create image '%s'"), pCache->pszFilename);
1332	break;
1333	}
1334
1335	/* Allocate block bitmap. */
1336	uint32_t cBlkMap = 0;
1337	rc = vciBlkMapCreate(cBlocks, &pCache->pBlkMap, &cBlkMap);
1338	if (RT_FAILURE(rc))
1339	{
1340	rc = vdIfError(pCache->pIfError, rc, RT_SRC_POS, N_("VCI: cannot create block bitmap '%s'"), pCache->pszFilename);
1341	break;
1342	}
1343
1344	/*
1345	* Allocate space for the header in the block bitmap.
1346	* Because the block map is empty the header has to start at block 0
1347	*/
1348	uint64_t offHdr = 0;
1349	rc = vciBlkMapAllocate(pCache->pBlkMap, VCI_BYTE2BLOCK(sizeof(VciHdr)), VCIBLKMAP_ALLOC_META, &offHdr);
1350	if (RT_FAILURE(rc))
1351	{
1352	rc = vdIfError(pCache->pIfError, rc, RT_SRC_POS, N_("VCI: cannot allocate space for header in block bitmap '%s'"), pCache->pszFilename);
1353	break;
1354	}
1355
1356	Assert(offHdr == 0);
1357
1358	/*
1359	* Allocate space for the block map itself.
1360	*/
1361	uint64_t offBlkMap = 0;
1362	rc = vciBlkMapAllocate(pCache->pBlkMap, cBlkMap, VCIBLKMAP_ALLOC_META, &offBlkMap);
1363	if (RT_FAILURE(rc))
1364	{
1365	rc = vdIfError(pCache->pIfError, rc, RT_SRC_POS, N_("VCI: cannot allocate space for block map in block map '%s'"), pCache->pszFilename);
1366	break;
1367	}
1368
1369	/*
1370	* Allocate space for the tree root node.
1371	*/
1372	uint64_t offTreeRoot = 0;
1373	rc = vciBlkMapAllocate(pCache->pBlkMap, VCI_BYTE2BLOCK(sizeof(VciTreeNode)), VCIBLKMAP_ALLOC_META, &offTreeRoot);
1374	if (RT_FAILURE(rc))
1375	{
1376	rc = vdIfError(pCache->pIfError, rc, RT_SRC_POS, N_("VCI: cannot allocate space for block map in block map '%s'"), pCache->pszFilename);
1377	break;
1378	}
1379
1380	/*
1381	* Allocate the in memory root node.
1382	*/
1383	pCache->pRoot = (PVCITREENODE)RTMemAllocZ(sizeof(VCITREENODELEAF));
1384	if (!pCache->pRoot)
1385	{
1386	rc = vdIfError(pCache->pIfError, rc, RT_SRC_POS, N_("VCI: cannot allocate B+-Tree root pointer '%s'"), pCache->pszFilename);
1387	break;
1388	}
1389
1390	pCache->pRoot->u8Type = VCI_TREE_NODE_TYPE_LEAF;
1391	/* Rest remains 0 as the tree is still empty. */
1392
1393	/*
1394	* Now that we are here we have all the basic structures and know where to place them in the image.
1395	* It's time to write it now.
1396	*/
1397
1398	/* Setup the header. */
1399	memset(&Hdr, 0, sizeof(VciHdr));
1400	Hdr.u32Signature = RT_H2LE_U32(VCI_HDR_SIGNATURE);
1401	Hdr.u32Version = RT_H2LE_U32(VCI_HDR_VERSION);
1402	Hdr.cBlocksCache = RT_H2LE_U64(cBlocks);
1403	Hdr.fUncleanShutdown = VCI_HDR_UNCLEAN_SHUTDOWN;
1404	Hdr.u32CacheType = uImageFlags & VD_IMAGE_FLAGS_FIXED
1405	? RT_H2LE_U32(VCI_HDR_CACHE_TYPE_FIXED)
1406	: RT_H2LE_U32(VCI_HDR_CACHE_TYPE_DYNAMIC);
1407	Hdr.offTreeRoot = RT_H2LE_U64(offTreeRoot);
1408	Hdr.offBlkMap = RT_H2LE_U64(offBlkMap);
1409	Hdr.cBlkMap = RT_H2LE_U32(cBlkMap);
1410
1411	rc = vdIfIoIntFileWriteSync(pCache->pIfIo, pCache->pStorage, offHdr, &Hdr,
1412	VCI_BYTE2BLOCK(sizeof(VciHdr)));
1413	if (RT_FAILURE(rc))
1414	{
1415	rc = vdIfError(pCache->pIfError, rc, RT_SRC_POS, N_("VCI: cannot write header '%s'"), pCache->pszFilename);
1416	break;
1417	}
1418
1419	rc = vciBlkMapSave(pCache->pBlkMap, pCache, offBlkMap, cBlkMap);
1420	if (RT_FAILURE(rc))
1421	{
1422	rc = vdIfError(pCache->pIfError, rc, RT_SRC_POS, N_("VCI: cannot write block map '%s'"), pCache->pszFilename);
1423	break;
1424	}
1425
1426	/* Setup the root tree. */
1427	memset(&NodeRoot, 0, sizeof(VciTreeNode));
1428	NodeRoot.u8Type = VCI_TREE_NODE_TYPE_LEAF;
1429
1430	rc = vdIfIoIntFileWriteSync(pCache->pIfIo, pCache->pStorage, offTreeRoot,
1431	&NodeRoot, VCI_BYTE2BLOCK(sizeof(VciTreeNode)));
1432	if (RT_FAILURE(rc))
1433	{
1434	rc = vdIfError(pCache->pIfError, rc, RT_SRC_POS, N_("VCI: cannot write root node '%s'"), pCache->pszFilename);
1435	break;
1436	}
1437
1438	rc = vciFlushImage(pCache);
1439	if (RT_FAILURE(rc))
1440	{
1441	rc = vdIfError(pCache->pIfError, rc, RT_SRC_POS, N_("VCI: cannot flush '%s'"), pCache->pszFilename);
1442	break;
1443	}
1444
1445	pCache->cbSize = cbSize;
1446
1447	} while (0);
1448
1449	if (RT_SUCCESS(rc) && pfnProgress)
1450	pfnProgress(pvUser, uPercentStart + uPercentSpan);
1451
1452	if (RT_FAILURE(rc))
1453	vciFreeImage(pCache, rc != VERR_ALREADY_EXISTS);
1454	return rc;
1455	}
1456
1457	/** @copydoc VDCACHEBACKEND::pfnProbe */
1458	static DECLCALLBACK(int) vciProbe(const char *pszFilename, PVDINTERFACE pVDIfsDisk,
1459	PVDINTERFACE pVDIfsImage)
1460	{
1461	RT_NOREF1(pVDIfsDisk);
1462	VciHdr Hdr;
1463	PVDIOSTORAGE pStorage = NULL;
1464	uint64_t cbFile;
1465	int rc = VINF_SUCCESS;
1466
1467	LogFlowFunc(("pszFilename=\"%s\"\n", pszFilename));
1468
1469	PVDINTERFACEIOINT pIfIo = VDIfIoIntGet(pVDIfsImage);
1470	AssertPtrReturn(pIfIo, VERR_INVALID_PARAMETER);
1471
1472	rc = vdIfIoIntFileOpen(pIfIo, pszFilename,
1473	VDOpenFlagsToFileOpenFlags(VD_OPEN_FLAGS_READONLY,
1474	false /* fCreate */),
1475	&pStorage);
1476	if (RT_FAILURE(rc))
1477	goto out;
1478
1479	rc = vdIfIoIntFileGetSize(pIfIo, pStorage, &cbFile);
1480	if (RT_FAILURE(rc) \|\| cbFile < sizeof(VciHdr))
1481	{
1482	rc = VERR_VD_GEN_INVALID_HEADER;
1483	goto out;
1484	}
1485
1486	rc = vdIfIoIntFileReadSync(pIfIo, pStorage, 0, &Hdr, sizeof(Hdr));
1487	if (RT_FAILURE(rc))
1488	{
1489	rc = VERR_VD_GEN_INVALID_HEADER;
1490	goto out;
1491	}
1492
1493	Hdr.u32Signature = RT_LE2H_U32(Hdr.u32Signature);
1494	Hdr.u32Version = RT_LE2H_U32(Hdr.u32Version);
1495	Hdr.cBlocksCache = RT_LE2H_U64(Hdr.cBlocksCache);
1496	Hdr.u32CacheType = RT_LE2H_U32(Hdr.u32CacheType);
1497	Hdr.offTreeRoot = RT_LE2H_U64(Hdr.offTreeRoot);
1498	Hdr.offBlkMap = RT_LE2H_U64(Hdr.offBlkMap);
1499	Hdr.cBlkMap = RT_LE2H_U32(Hdr.cBlkMap);
1500
1501	if ( Hdr.u32Signature == VCI_HDR_SIGNATURE
1502	&& Hdr.u32Version == VCI_HDR_VERSION)
1503	rc = VINF_SUCCESS;
1504	else
1505	rc = VERR_VD_GEN_INVALID_HEADER;
1506
1507	out:
1508	if (pStorage)
1509	vdIfIoIntFileClose(pIfIo, pStorage);
1510
1511	LogFlowFunc(("returns %Rrc\n", rc));
1512	return rc;
1513	}
1514
1515	/** @copydoc VDCACHEBACKEND::pfnOpen */
1516	static DECLCALLBACK(int) vciOpen(const char *pszFilename, unsigned uOpenFlags,
1517	PVDINTERFACE pVDIfsDisk, PVDINTERFACE pVDIfsImage,
1518	void **ppBackendData)
1519	{
1520	LogFlowFunc(("pszFilename=\"%s\" uOpenFlags=%#x pVDIfsDisk=%#p pVDIfsImage=%#p ppBackendData=%#p\n", pszFilename, uOpenFlags, pVDIfsDisk, pVDIfsImage, ppBackendData));
1521	int rc;
1522	PVCICACHE pCache;
1523
1524	/* Check open flags. All valid flags are supported. */
1525	if (uOpenFlags & ~VD_OPEN_FLAGS_MASK)
1526	{
1527	rc = VERR_INVALID_PARAMETER;
1528	goto out;
1529	}
1530
1531	/* Check remaining arguments. */
1532	if ( !RT_VALID_PTR(pszFilename)
1533	\|\| !*pszFilename)
1534	{
1535	rc = VERR_INVALID_PARAMETER;
1536	goto out;
1537	}
1538
1539
1540	pCache = (PVCICACHE)RTMemAllocZ(sizeof(VCICACHE));
1541	if (!pCache)
1542	{
1543	rc = VERR_NO_MEMORY;
1544	goto out;
1545	}
1546	pCache->pszFilename = pszFilename;
1547	pCache->pStorage = NULL;
1548	pCache->pVDIfsDisk = pVDIfsDisk;
1549	pCache->pVDIfsImage = pVDIfsImage;
1550
1551	rc = vciOpenImage(pCache, uOpenFlags);
1552	if (RT_SUCCESS(rc))
1553	*ppBackendData = pCache;
1554	else
1555	RTMemFree(pCache);
1556
1557	out:
1558	LogFlowFunc(("returns %Rrc (pBackendData=%#p)\n", rc, *ppBackendData));
1559	return rc;
1560	}
1561
1562	/** @copydoc VDCACHEBACKEND::pfnCreate */
1563	static DECLCALLBACK(int) vciCreate(const char *pszFilename, uint64_t cbSize,
1564	unsigned uImageFlags, const char *pszComment,
1565	PCRTUUID pUuid, unsigned uOpenFlags,
1566	unsigned uPercentStart, unsigned uPercentSpan,
1567	PVDINTERFACE pVDIfsDisk, PVDINTERFACE pVDIfsImage,
1568	PVDINTERFACE pVDIfsOperation, void **ppBackendData)
1569	{
1570	RT_NOREF1(pUuid);
1571	LogFlowFunc(("pszFilename=\"%s\" cbSize=%llu uImageFlags=%#x pszComment=\"%s\" Uuid=%RTuuid uOpenFlags=%#x uPercentStart=%u uPercentSpan=%u pVDIfsDisk=%#p pVDIfsImage=%#p pVDIfsOperation=%#p ppBackendData=%#p",
1572	pszFilename, cbSize, uImageFlags, pszComment, pUuid, uOpenFlags, uPercentStart, uPercentSpan, pVDIfsDisk, pVDIfsImage, pVDIfsOperation, ppBackendData));
1573	int rc;
1574	PVCICACHE pCache;
1575
1576	PFNVDPROGRESS pfnProgress = NULL;
1577	void *pvUser = NULL;
1578	PVDINTERFACEPROGRESS pIfProgress = VDIfProgressGet(pVDIfsOperation);
1579	if (pIfProgress)
1580	{
1581	pfnProgress = pIfProgress->pfnProgress;
1582	pvUser = pIfProgress->Core.pvUser;
1583	}
1584
1585	/* Check open flags. All valid flags are supported. */
1586	if (uOpenFlags & ~VD_OPEN_FLAGS_MASK)
1587	{
1588	rc = VERR_INVALID_PARAMETER;
1589	goto out;
1590	}
1591
1592	/* Check remaining arguments. */
1593	if ( !RT_VALID_PTR(pszFilename)
1594	\|\| !*pszFilename)
1595	{
1596	rc = VERR_INVALID_PARAMETER;
1597	goto out;
1598	}
1599
1600	pCache = (PVCICACHE)RTMemAllocZ(sizeof(VCICACHE));
1601	if (!pCache)
1602	{
1603	rc = VERR_NO_MEMORY;
1604	goto out;
1605	}
1606	pCache->pszFilename = pszFilename;
1607	pCache->pStorage = NULL;
1608	pCache->pVDIfsDisk = pVDIfsDisk;
1609	pCache->pVDIfsImage = pVDIfsImage;
1610
1611	rc = vciCreateImage(pCache, cbSize, uImageFlags, pszComment, uOpenFlags,
1612	pfnProgress, pvUser, uPercentStart, uPercentSpan);
1613	if (RT_SUCCESS(rc))
1614	{
1615	/* So far the image is opened in read/write mode. Make sure the
1616	* image is opened in read-only mode if the caller requested that. */
1617	if (uOpenFlags & VD_OPEN_FLAGS_READONLY)
1618	{
1619	vciFreeImage(pCache, false);
1620	rc = vciOpenImage(pCache, uOpenFlags);
1621	if (RT_FAILURE(rc))
1622	{
1623	RTMemFree(pCache);
1624	goto out;
1625	}
1626	}
1627	*ppBackendData = pCache;
1628	}
1629	else
1630	RTMemFree(pCache);
1631
1632	out:
1633	LogFlowFunc(("returns %Rrc (pBackendData=%#p)\n", rc, *ppBackendData));
1634	return rc;
1635	}
1636
1637	/** @copydoc VDCACHEBACKEND::pfnClose */
1638	static DECLCALLBACK(int) vciClose(void *pBackendData, bool fDelete)
1639	{
1640	LogFlowFunc(("pBackendData=%#p fDelete=%d\n", pBackendData, fDelete));
1641	PVCICACHE pCache = (PVCICACHE)pBackendData;
1642	int rc;
1643
1644	rc = vciFreeImage(pCache, fDelete);
1645	RTMemFree(pCache);
1646
1647	LogFlowFunc(("returns %Rrc\n", rc));
1648	return rc;
1649	}
1650
1651	/** @copydoc VDCACHEBACKEND::pfnRead */
1652	static DECLCALLBACK(int) vciRead(void *pBackendData, uint64_t uOffset, size_t cbToRead,
1653	PVDIOCTX pIoCtx, size_t *pcbActuallyRead)
1654	{
1655	LogFlowFunc(("pBackendData=%#p uOffset=%llu cbToRead=%zu pIoCtx=%#p pcbActuallyRead=%#p\n",
1656	pBackendData, uOffset, cbToRead, pIoCtx, pcbActuallyRead));
1657	PVCICACHE pCache = (PVCICACHE)pBackendData;
1658	int rc = VINF_SUCCESS;
1659	PVCICACHEEXTENT pExtent;
1660	uint64_t cBlocksToRead = VCI_BYTE2BLOCK(cbToRead);
1661	uint64_t offBlockAddr = VCI_BYTE2BLOCK(uOffset);
1662
1663	AssertPtr(pCache);
1664	Assert(uOffset % 512 == 0);
1665	Assert(cbToRead % 512 == 0);
1666
1667	pExtent = vciCacheExtentLookup(pCache, offBlockAddr, NULL);
1668	if (pExtent)
1669	{
1670	uint64_t offRead = offBlockAddr - pExtent->u64BlockOffset;
1671	cBlocksToRead = RT_MIN(cBlocksToRead, pExtent->u32Blocks - offRead);
1672
1673	rc = vdIfIoIntFileReadUser(pCache->pIfIo, pCache->pStorage,
1674	pExtent->u64BlockAddr + offRead,
1675	pIoCtx, cBlocksToRead);
1676	}
1677	else
1678	{
1679	/** @todo Best fit to check whether we have cached data later and set
1680	* pcbActuallyRead accordingly. */
1681	rc = VERR_VD_BLOCK_FREE;
1682	}
1683
1684	if (pcbActuallyRead)
1685	*pcbActuallyRead = VCI_BLOCK2BYTE(cBlocksToRead);
1686
1687	LogFlowFunc(("returns %Rrc\n", rc));
1688	return rc;
1689	}
1690
1691	/** @copydoc VDCACHEBACKEND::pfnWrite */
1692	static DECLCALLBACK(int) vciWrite(void *pBackendData, uint64_t uOffset, size_t cbToWrite,
1693	PVDIOCTX pIoCtx, size_t *pcbWriteProcess)
1694	{
1695	RT_NOREF5(pBackendData, uOffset, cbToWrite, pIoCtx, pcbWriteProcess);
1696	LogFlowFunc(("pBackendData=%#p uOffset=%llu cbToWrite=%zu pIoCtx=%#p pcbWriteProcess=%#p\n",
1697	pBackendData, uOffset, cbToWrite, pIoCtx, pcbWriteProcess));
1698	PVCICACHE pCache = (PVCICACHE)pBackendData;
1699	int rc = VINF_SUCCESS;
1700	uint64_t cBlocksToWrite = VCI_BYTE2BLOCK(cbToWrite);
1701	//uint64_t offBlockAddr = VCI_BYTE2BLOCK(uOffset);
1702
1703	AssertPtr(pCache); NOREF(pCache);
1704	Assert(uOffset % 512 == 0);
1705	Assert(cbToWrite % 512 == 0);
1706	while (cBlocksToWrite)
1707	{
1708
1709	}
1710
1711	pcbWriteProcess = cbToWrite; /* @todo Implement. */
1712
1713	LogFlowFunc(("returns %Rrc\n", rc));
1714	return rc;
1715	}
1716
1717	/** @copydoc VDCACHEBACKEND::pfnFlush */
1718	static DECLCALLBACK(int) vciFlush(void *pBackendData, PVDIOCTX pIoCtx)
1719	{
1720	RT_NOREF1(pIoCtx);
1721	LogFlowFunc(("pBackendData=%#p\n", pBackendData));
1722	PVCICACHE pCache = (PVCICACHE)pBackendData;
1723
1724	int rc = vciFlushImage(pCache);
1725	LogFlowFunc(("returns %Rrc\n", rc));
1726	return rc;
1727	}
1728
1729	/** @copydoc VDCACHEBACKEND::pfnGetVersion */
1730	static DECLCALLBACK(unsigned) vciGetVersion(void *pBackendData)
1731	{
1732	LogFlowFunc(("pBackendData=%#p\n", pBackendData));
1733	PVCICACHE pCache = (PVCICACHE)pBackendData;
1734
1735	AssertPtr(pCache);
1736
1737	if (pCache)
1738	return 1;
1739	else
1740	return 0;
1741	}
1742
1743	/** @copydoc VDCACHEBACKEND::pfnGetSize */
1744	static DECLCALLBACK(uint64_t) vciGetSize(void *pBackendData)
1745	{
1746	LogFlowFunc(("pBackendData=%#p\n", pBackendData));
1747	PVCICACHE pCache = (PVCICACHE)pBackendData;
1748	uint64_t cb = 0;
1749
1750	AssertPtr(pCache);
1751
1752	if (pCache && pCache->pStorage)
1753	cb = pCache->cbSize;
1754
1755	LogFlowFunc(("returns %llu\n", cb));
1756	return cb;
1757	}
1758
1759	/** @copydoc VDCACHEBACKEND::pfnGetFileSize */
1760	static DECLCALLBACK(uint64_t) vciGetFileSize(void *pBackendData)
1761	{
1762	LogFlowFunc(("pBackendData=%#p\n", pBackendData));
1763	PVCICACHE pCache = (PVCICACHE)pBackendData;
1764	uint64_t cb = 0;
1765
1766	AssertPtr(pCache);
1767
1768	if (pCache)
1769	{
1770	uint64_t cbFile;
1771	if (pCache->pStorage)
1772	{
1773	int rc = vdIfIoIntFileGetSize(pCache->pIfIo, pCache->pStorage, &cbFile);
1774	if (RT_SUCCESS(rc))
1775	cb = cbFile;
1776	}
1777	}
1778
1779	LogFlowFunc(("returns %lld\n", cb));
1780	return cb;
1781	}
1782
1783	/** @copydoc VDCACHEBACKEND::pfnGetImageFlags */
1784	static DECLCALLBACK(unsigned) vciGetImageFlags(void *pBackendData)
1785	{
1786	LogFlowFunc(("pBackendData=%#p\n", pBackendData));
1787	PVCICACHE pCache = (PVCICACHE)pBackendData;
1788	unsigned uImageFlags;
1789
1790	AssertPtr(pCache);
1791
1792	if (pCache)
1793	uImageFlags = pCache->uImageFlags;
1794	else
1795	uImageFlags = 0;
1796
1797	LogFlowFunc(("returns %#x\n", uImageFlags));
1798	return uImageFlags;
1799	}
1800
1801	/** @copydoc VDCACHEBACKEND::pfnGetOpenFlags */
1802	static DECLCALLBACK(unsigned) vciGetOpenFlags(void *pBackendData)
1803	{
1804	LogFlowFunc(("pBackendData=%#p\n", pBackendData));
1805	PVCICACHE pCache = (PVCICACHE)pBackendData;
1806	unsigned uOpenFlags;
1807
1808	AssertPtr(pCache);
1809
1810	if (pCache)
1811	uOpenFlags = pCache->uOpenFlags;
1812	else
1813	uOpenFlags = 0;
1814
1815	LogFlowFunc(("returns %#x\n", uOpenFlags));
1816	return uOpenFlags;
1817	}
1818
1819	/** @copydoc VDCACHEBACKEND::pfnSetOpenFlags */
1820	static DECLCALLBACK(int) vciSetOpenFlags(void *pBackendData, unsigned uOpenFlags)
1821	{
1822	LogFlowFunc(("pBackendData=%#p\n uOpenFlags=%#x", pBackendData, uOpenFlags));
1823	PVCICACHE pCache = (PVCICACHE)pBackendData;
1824	int rc;
1825
1826	/* Image must be opened and the new flags must be valid. Just readonly and
1827	* info flags are supported. */
1828	if (!pCache \|\| (uOpenFlags & ~(VD_OPEN_FLAGS_READONLY \| VD_OPEN_FLAGS_INFO)))
1829	{
1830	rc = VERR_INVALID_PARAMETER;
1831	goto out;
1832	}
1833
1834	/* Implement this operation via reopening the image. */
1835	rc = vciFreeImage(pCache, false);
1836	if (RT_FAILURE(rc))
1837	goto out;
1838	rc = vciOpenImage(pCache, uOpenFlags);
1839
1840	out:
1841	LogFlowFunc(("returns %Rrc\n", rc));
1842	return rc;
1843	}
1844
1845	/** @copydoc VDCACHEBACKEND::pfnGetComment */
1846	static DECLCALLBACK(int) vciGetComment(void pBackendData, char pszComment,
1847	size_t cbComment)
1848	{
1849	RT_NOREF2(pszComment, cbComment);
1850	LogFlowFunc(("pBackendData=%#p pszComment=%#p cbComment=%zu\n", pBackendData, pszComment, cbComment));
1851	PVCICACHE pCache = (PVCICACHE)pBackendData;
1852	int rc;
1853
1854	AssertPtr(pCache);
1855
1856	if (pCache)
1857	rc = VERR_NOT_SUPPORTED;
1858	else
1859	rc = VERR_VD_NOT_OPENED;
1860
1861	LogFlowFunc(("returns %Rrc comment='%s'\n", rc, pszComment));
1862	return rc;
1863	}
1864
1865	/** @copydoc VDCACHEBACKEND::pfnSetComment */
1866	static DECLCALLBACK(int) vciSetComment(void pBackendData, const char pszComment)
1867	{
1868	RT_NOREF1(pszComment);
1869	LogFlowFunc(("pBackendData=%#p pszComment=\"%s\"\n", pBackendData, pszComment));
1870	PVCICACHE pCache = (PVCICACHE)pBackendData;
1871	int rc;
1872
1873	AssertPtr(pCache);
1874
1875	if (pCache)
1876	{
1877	if (pCache->uOpenFlags & VD_OPEN_FLAGS_READONLY)
1878	rc = VERR_VD_IMAGE_READ_ONLY;
1879	else
1880	rc = VERR_NOT_SUPPORTED;
1881	}
1882	else
1883	rc = VERR_VD_NOT_OPENED;
1884
1885	LogFlowFunc(("returns %Rrc\n", rc));
1886	return rc;
1887	}
1888
1889	/** @copydoc VDCACHEBACKEND::pfnGetUuid */
1890	static DECLCALLBACK(int) vciGetUuid(void *pBackendData, PRTUUID pUuid)
1891	{
1892	RT_NOREF1(pUuid);
1893	LogFlowFunc(("pBackendData=%#p pUuid=%#p\n", pBackendData, pUuid));
1894	PVCICACHE pCache = (PVCICACHE)pBackendData;
1895	int rc;
1896
1897	AssertPtr(pCache);
1898
1899	if (pCache)
1900	rc = VERR_NOT_SUPPORTED;
1901	else
1902	rc = VERR_VD_NOT_OPENED;
1903
1904	LogFlowFunc(("returns %Rrc (%RTuuid)\n", rc, pUuid));
1905	return rc;
1906	}
1907
1908	/** @copydoc VDCACHEBACKEND::pfnSetUuid */
1909	static DECLCALLBACK(int) vciSetUuid(void *pBackendData, PCRTUUID pUuid)
1910	{
1911	RT_NOREF1(pUuid);
1912	LogFlowFunc(("pBackendData=%#p Uuid=%RTuuid\n", pBackendData, pUuid));
1913	PVCICACHE pCache = (PVCICACHE)pBackendData;
1914	int rc;
1915
1916	LogFlowFunc(("%RTuuid\n", pUuid));
1917	AssertPtr(pCache);
1918
1919	if (pCache)
1920	{
1921	if (!(pCache->uOpenFlags & VD_OPEN_FLAGS_READONLY))
1922	rc = VERR_NOT_SUPPORTED;
1923	else
1924	rc = VERR_VD_IMAGE_READ_ONLY;
1925	}
1926	else
1927	rc = VERR_VD_NOT_OPENED;
1928
1929	LogFlowFunc(("returns %Rrc\n", rc));
1930	return rc;
1931	}
1932
1933	/** @copydoc VDCACHEBACKEND::pfnGetModificationUuid */
1934	static DECLCALLBACK(int) vciGetModificationUuid(void *pBackendData, PRTUUID pUuid)
1935	{
1936	RT_NOREF1(pUuid);
1937	LogFlowFunc(("pBackendData=%#p pUuid=%#p\n", pBackendData, pUuid));
1938	PVCICACHE pCache = (PVCICACHE)pBackendData;
1939	int rc;
1940
1941	AssertPtr(pCache);
1942
1943	if (pCache)
1944	rc = VERR_NOT_SUPPORTED;
1945	else
1946	rc = VERR_VD_NOT_OPENED;
1947
1948	LogFlowFunc(("returns %Rrc (%RTuuid)\n", rc, pUuid));
1949	return rc;
1950	}
1951
1952	/** @copydoc VDCACHEBACKEND::pfnSetModificationUuid */
1953	static DECLCALLBACK(int) vciSetModificationUuid(void *pBackendData, PCRTUUID pUuid)
1954	{
1955	RT_NOREF1(pUuid);
1956	LogFlowFunc(("pBackendData=%#p Uuid=%RTuuid\n", pBackendData, pUuid));
1957	PVCICACHE pCache = (PVCICACHE)pBackendData;
1958	int rc;
1959
1960	AssertPtr(pCache);
1961
1962	if (pCache)
1963	{
1964	if (!(pCache->uOpenFlags & VD_OPEN_FLAGS_READONLY))
1965	rc = VERR_NOT_SUPPORTED;
1966	else
1967	rc = VERR_VD_IMAGE_READ_ONLY;
1968	}
1969	else
1970	rc = VERR_VD_NOT_OPENED;
1971
1972	LogFlowFunc(("returns %Rrc\n", rc));
1973	return rc;
1974	}
1975
1976	/** @copydoc VDCACHEBACKEND::pfnDump */
1977	static DECLCALLBACK(void) vciDump(void *pBackendData)
1978	{
1979	NOREF(pBackendData);
1980	}
1981
1982
1983	const VDCACHEBACKEND g_VciCacheBackend =
1984	{
1985	/* u32Version */
1986	VD_CACHEBACKEND_VERSION,
1987	/* pszBackendName */
1988	"vci",
1989	/* uBackendCaps */
1990	VD_CAP_CREATE_FIXED \| VD_CAP_CREATE_DYNAMIC \| VD_CAP_FILE \| VD_CAP_VFS,
1991	/* papszFileExtensions */
1992	s_apszVciFileExtensions,
1993	/* paConfigInfo */
1994	NULL,
1995	/* pfnProbe */
1996	vciProbe,
1997	/* pfnOpen */
1998	vciOpen,
1999	/* pfnCreate */
2000	vciCreate,
2001	/* pfnClose */
2002	vciClose,
2003	/* pfnRead */
2004	vciRead,
2005	/* pfnWrite */
2006	vciWrite,
2007	/* pfnFlush */
2008	vciFlush,
2009	/* pfnDiscard */
2010	NULL,
2011	/* pfnGetVersion */
2012	vciGetVersion,
2013	/* pfnGetSize */
2014	vciGetSize,
2015	/* pfnGetFileSize */
2016	vciGetFileSize,
2017	/* pfnGetImageFlags */
2018	vciGetImageFlags,
2019	/* pfnGetOpenFlags */
2020	vciGetOpenFlags,
2021	/* pfnSetOpenFlags */
2022	vciSetOpenFlags,
2023	/* pfnGetComment */
2024	vciGetComment,
2025	/* pfnSetComment */
2026	vciSetComment,
2027	/* pfnGetUuid */
2028	vciGetUuid,
2029	/* pfnSetUuid */
2030	vciSetUuid,
2031	/* pfnGetModificationUuid */
2032	vciGetModificationUuid,
2033	/* pfnSetModificationUuid */
2034	vciSetModificationUuid,
2035	/* pfnDump */
2036	vciDump,
2037	/* pfnComposeLocation */
2038	NULL,
2039	/* pfnComposeName */
2040	NULL,
2041	/* u32VersionEnd */
2042	VD_CACHEBACKEND_VERSION
2043	};
2044

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source: vbox/trunk/src/VBox/Storage/VCICache.cpp@ 93231

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