VCICache.cpp@ 63905

Last change on this file since 63905 was 63905, checked in by vboxsync, 8 years ago
Storage/VD: Add proper versioning of the backend structures instead of just relying on the structure size to make changing callback signatures possible in the future and still being able to reject incompatible plugins
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1	/* $Id: VCICache.cpp 63905 2016-09-20 08:31:05Z vboxsync $ */
2	/** @file
3	* VCICacheCore - VirtualBox Cache Image, Core Code.
4	*/
5
6	/*
7	* Copyright (C) 2006-2016 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 pcbBlkMap 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 = RT_H2LE_U32(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 pVDIfsCache,
1459	PVDINTERFACE pVDIfsImage)
1460	{
1461	RT_NOREF1(pVDIfsCache);
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 ( !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 ( !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@ 63905

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