VCICache.cpp@ 51287

Last change on this file since 51287 was 50988, checked in by vboxsync, 11 years ago
Storage/VD: Cleanup VD plugin handling. One shared object can now support an arbitrary number of image backends instead of just one like before
Property svn:eol-style set to `native` Property svn:keywords set to `Author Date Id Revision`
File size: 64.0 KB

Line
1	/* $Id: VCICache.cpp 50988 2014-04-07 19:36:54Z vboxsync $ */
2	/** @file
3	* VCICacheCore - VirtualBox Cache Image, Core Code.
4	*/
5
6	/*
7	* Copyright (C) 2006-2013 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	* Header Files *
20	*******************************************************************************/
21	#define LOG_GROUP LOG_GROUP_VD_RAW /** @todo logging group */
22	#include <VBox/vd-cache-backend.h>
23	#include <VBox/err.h>
24
25	#include <VBox/log.h>
26	#include <iprt/assert.h>
27	#include <iprt/alloc.h>
28	#include <iprt/file.h>
29	#include <iprt/asm.h>
30
31	#include "VDBackends.h"
32
33	/*******************************************************************************
34	* On disk data structures *
35	*******************************************************************************/
36
37	/** @note All structures which are written to the disk are written in camel case
38	* and packed. */
39
40	/** Block size used internally, because we cache sectors the smallest unit we
41	* have to care about is 512 bytes. */
42	#define VCI_BLOCK_SIZE 512
43
44	/** Convert block number/size to byte offset/size. */
45	#define VCI_BLOCK2BYTE(u) ((uint64_t)(u) << 9)
46
47	/** Convert byte offset/size to block number/size. */
48	#define VCI_BYTE2BLOCK(u) ((u) >> 9)
49
50	/**
51	* The VCI header - at the beginning of the file.
52	*
53	* All entries a stored in little endian order.
54	*/
55	#pragma pack(1)
56	typedef struct VciHdr
57	{
58	/** The signature to identify a cache image. */
59	uint32_t u32Signature;
60	/** Version of the layout of metadata in the cache. */
61	uint32_t u32Version;
62	/** Maximum size of the cache file in blocks.
63	* This includes all metadata. */
64	uint64_t cBlocksCache;
65	/** Flag indicating whether the cache was closed cleanly. */
66	uint8_t fUncleanShutdown;
67	/** Cache type. */
68	uint32_t u32CacheType;
69	/** Offset of the B+-Tree root in the image in blocks. */
70	uint64_t offTreeRoot;
71	/** Offset of the block allocation bitmap in blocks. */
72	uint64_t offBlkMap;
73	/** Size of the block allocation bitmap in blocks. */
74	uint32_t cBlkMap;
75	/** UUID of the image. */
76	RTUUID uuidImage;
77	/** Modification UUID for the cache. */
78	RTUUID uuidModification;
79	/** Reserved for future use. */
80	uint8_t abReserved[951];
81	} VciHdr, *PVciHdr;
82	#pragma pack()
83	AssertCompileSize(VciHdr, 2 * VCI_BLOCK_SIZE);
84
85	/** VCI signature to identify a valid image. */
86	#define VCI_HDR_SIGNATURE UINT32_C(0x00494356) /* \0ICV */
87	/** Current version we support. */
88	#define VCI_HDR_VERSION UINT32_C(0x00000001)
89
90	/** Value for an unclean cache shutdown. */
91	#define VCI_HDR_UNCLEAN_SHUTDOWN UINT8_C(0x01)
92	/** Value for a clean cache shutdown. */
93	#define VCI_HDR_CLEAN_SHUTDOWN UINT8_C(0x00)
94
95	/** Cache type: Dynamic image growing to the maximum value. */
96	#define VCI_HDR_CACHE_TYPE_DYNAMIC UINT32_C(0x00000001)
97	/** Cache type: Fixed image, space is preallocated. */
98	#define VCI_HDR_CACHE_TYPE_FIXED UINT32_C(0x00000002)
99
100	/**
101	* On disk representation of an extent describing a range of cached data.
102	*
103	* All entries a stored in little endian order.
104	*/
105	#pragma pack(1)
106	typedef struct VciCacheExtent
107	{
108	/** Block address of the previous extent in the LRU list. */
109	uint64_t u64ExtentPrev;
110	/** Block address of the next extent in the LRU list. */
111	uint64_t u64ExtentNext;
112	/** Flags (for compression, encryption etc.) - currently unused and should be always 0. */
113	uint8_t u8Flags;
114	/** Reserved */
115	uint8_t u8Reserved;
116	/** First block of cached data the extent represents. */
117	uint64_t u64BlockOffset;
118	/** Number of blocks the extent represents. */
119	uint32_t u32Blocks;
120	/** First block in the image where the data is stored. */
121	uint64_t u64BlockAddr;
122	} VciCacheExtent, *PVciCacheExtent;
123	#pragma pack()
124	AssertCompileSize(VciCacheExtent, 38);
125
126	/**
127	* On disk representation of an internal node.
128	*
129	* All entries a stored in little endian order.
130	*/
131	#pragma pack(1)
132	typedef struct VciTreeNodeInternal
133	{
134	/** First block of cached data the internal node represents. */
135	uint64_t u64BlockOffset;
136	/** Number of blocks the internal node represents. */
137	uint32_t u32Blocks;
138	/** Block address in the image where the next node in the tree is stored. */
139	uint64_t u64ChildAddr;
140	} VciTreeNodeInternal, *PVciTreeNodeInternal;
141	#pragma pack()
142	AssertCompileSize(VciTreeNodeInternal, 20);
143
144	/**
145	* On-disk representation of a node in the B+-Tree.
146	*
147	* All entries a stored in little endian order.
148	*/
149	#pragma pack(1)
150	typedef struct VciTreeNode
151	{
152	/** Type of the node (root, internal, leaf). */
153	uint8_t u8Type;
154	/** Data in the node. */
155	uint8_t au8Data[4095];
156	} VciTreeNode, *PVciTreeNode;
157	#pragma pack()
158	AssertCompileSize(VciTreeNode, 8 * VCI_BLOCK_SIZE);
159
160	/** Node type: Internal node containing links to other nodes (VciTreeNodeInternal). */
161	#define VCI_TREE_NODE_TYPE_INTERNAL UINT8_C(0x01)
162	/** Node type: Leaf of the tree (VciCacheExtent). */
163	#define VCI_TREE_NODE_TYPE_LEAF UINT8_C(0x02)
164
165	/** Number of cache extents described by one node. */
166	#define VCI_TREE_EXTENTS_PER_NODE ((sizeof(VciTreeNode)-1) / sizeof(VciCacheExtent))
167	/** Number of internal nodes managed by one tree node. */
168	#define VCI_TREE_INTERNAL_NODES_PER_NODE ((sizeof(VciTreeNode)-1) / sizeof(VciTreeNodeInternal))
169
170	/**
171	* VCI block bitmap header.
172	*
173	* All entries a stored in little endian order.
174	*/
175	#pragma pack(1)
176	typedef struct VciBlkMap
177	{
178	/** Magic of the block bitmap. */
179	uint32_t u32Magic;
180	/** Version of the block bitmap. */
181	uint32_t u32Version;
182	/** Number of blocks this block map manages. */
183	uint64_t cBlocks;
184	/** Number of free blocks. */
185	uint64_t cBlocksFree;
186	/** Number of blocks allocated for metadata. */
187	uint64_t cBlocksAllocMeta;
188	/** Number of blocks allocated for actual cached data. */
189	uint64_t cBlocksAllocData;
190	/** Reserved for future use. */
191	uint8_t au8Reserved[472];
192	} VciBlkMap, *PVciBlkMap;
193	#pragma pack()
194	AssertCompileSize(VciBlkMap, VCI_BLOCK_SIZE);
195
196	/** The magic which identifies a block map. */
197	#define VCI_BLKMAP_MAGIC UINT32_C(0x4b4c4256) /* KLBV */
198	/** Current version. */
199	#define VCI_BLKMAP_VERSION UINT32_C(0x00000001)
200
201	/** Block bitmap entry */
202	typedef uint8_t VciBlkMapEnt;
203
204	/*******************************************************************************
205	* Constants And Macros, Structures and Typedefs *
206	*******************************************************************************/
207
208	/**
209	* Block range descriptor.
210	*/
211	typedef struct VCIBLKRANGEDESC
212	{
213	/** Previous entry in the list. */
214	struct VCIBLKRANGEDESC *pPrev;
215	/** Next entry in the list. */
216	struct VCIBLKRANGEDESC *pNext;
217	/** Start address of the range. */
218	uint64_t offAddrStart;
219	/** Number of blocks in the range. */
220	uint64_t cBlocks;
221	/** Flag whether the range is free or allocated. */
222	bool fFree;
223	} VCIBLKRANGEDESC, *PVCIBLKRANGEDESC;
224
225	/**
226	* Block map for the cache image - in memory structure.
227	*/
228	typedef struct VCIBLKMAP
229	{
230	/** Number of blocks the map manages. */
231	uint64_t cBlocks;
232	/** Number of blocks allocated for metadata. */
233	uint64_t cBlocksAllocMeta;
234	/** Number of blocks allocated for actual cached data. */
235	uint64_t cBlocksAllocData;
236	/** Number of free blocks. */
237	uint64_t cBlocksFree;
238
239	/** Pointer to the head of the block range list. */
240	PVCIBLKRANGEDESC pRangesHead;
241	/** Pointer to the tail of the block range list. */
242	PVCIBLKRANGEDESC pRangesTail;
243
244	} VCIBLKMAP;
245	/** Pointer to a block map. */
246	typedef VCIBLKMAP *PVCIBLKMAP;
247
248	/**
249	* B+-Tree node header.
250	*/
251	typedef struct VCITREENODE
252	{
253	/** Type of the node (VCI_TREE_NODE_TYPE_). /
254	uint8_t u8Type;
255	/** Block address where the node is stored. */
256	uint64_t u64BlockAddr;
257	/** Pointer to the parent. */
258	struct VCITREENODE *pParent;
259	} VCITREENODE, *PVCITREENODE;
260
261	/**
262	* B+-Tree node pointer.
263	*/
264	typedef struct VCITREENODEPTR
265	{
266	/** Flag whether the node is in memory or still on the disk. */
267	bool fInMemory;
268	/** Type dependent data. */
269	union
270	{
271	/** Pointer to a in memory node. */
272	PVCITREENODE pNode;
273	/** Start block address of the node. */
274	uint64_t offAddrBlockNode;
275	} u;
276	} VCITREENODEPTR, *PVCITREENODEPTR;
277
278	/**
279	* Internal node.
280	*/
281	typedef struct VCINODEINTERNAL
282	{
283	/** First block of cached data the internal node represents. */
284	uint64_t u64BlockOffset;
285	/** Number of blocks the internal node represents. */
286	uint32_t u32Blocks;
287	/** Pointer to the child node. */
288	VCITREENODEPTR PtrChild;
289	} VCINODEINTERNAL, *PVCINODEINTERNAL;
290
291	/**
292	* A in memory internal B+-tree node.
293	*/
294	typedef struct VCITREENODEINT
295	{
296	/** Node core. */
297	VCITREENODE Core;
298	/** Number of used nodes. */
299	unsigned cUsedNodes;
300	/** Array of internal nodes. */
301	VCINODEINTERNAL aIntNodes[VCI_TREE_INTERNAL_NODES_PER_NODE];
302	} VCITREENODEINT, *PVCITREENODEINT;
303
304	/**
305	* A in memory cache extent.
306	*/
307	typedef struct VCICACHEEXTENT
308	{
309	/** First block of cached data the extent represents. */
310	uint64_t u64BlockOffset;
311	/** Number of blocks the extent represents. */
312	uint32_t u32Blocks;
313	/** First block in the image where the data is stored. */
314	uint64_t u64BlockAddr;
315	} VCICACHEEXTENT, *PVCICACHEEXTENT;
316
317	/**
318	* A in memory leaf B+-tree node.
319	*/
320	typedef struct VCITREENODELEAF
321	{
322	/** Node core. */
323	VCITREENODE Core;
324	/** Next leaf node in the list. */
325	struct VCITREENODELEAF *pNext;
326	/** Number of used nodes. */
327	unsigned cUsedNodes;
328	/** The extents in the node. */
329	VCICACHEEXTENT aExtents[VCI_TREE_EXTENTS_PER_NODE];
330	} VCITREENODELEAF, *PVCITREENODELEAF;
331
332	/**
333	* VCI image data structure.
334	*/
335	typedef struct VCICACHE
336	{
337	/** Image name. */
338	const char *pszFilename;
339	/** Storage handle. */
340	PVDIOSTORAGE pStorage;
341
342	/** Pointer to the per-disk VD interface list. */
343	PVDINTERFACE pVDIfsDisk;
344	/** Pointer to the per-image VD interface list. */
345	PVDINTERFACE pVDIfsImage;
346	/** Error interface. */
347	PVDINTERFACEERROR pIfError;
348	/** I/O interface. */
349	PVDINTERFACEIOINT pIfIo;
350
351	/** Open flags passed by VBoxHD layer. */
352	unsigned uOpenFlags;
353	/** Image flags defined during creation or determined during open. */
354	unsigned uImageFlags;
355	/** Total size of the image. */
356	uint64_t cbSize;
357
358	/** Offset of the B+-Tree in the image in bytes. */
359	uint64_t offTreeRoot;
360	/** Pointer to the root node of the B+-Tree. */
361	PVCITREENODE pRoot;
362	/** Offset to the block allocation bitmap in bytes. */
363	uint64_t offBlksBitmap;
364	/** Block map. */
365	PVCIBLKMAP pBlkMap;
366	} VCICACHE, *PVCICACHE;
367
368	/** No block free in bitmap error code. */
369	#define VERR_VCI_NO_BLOCKS_FREE (-65536)
370
371	/** Flags for the block map allocator. */
372	#define VCIBLKMAP_ALLOC_DATA 0
373	#define VCIBLKMAP_ALLOC_META RT_BIT(0)
374	#define VCIBLKMAP_ALLOC_MASK 0x1
375
376	/*******************************************************************************
377	* Static Variables *
378	*******************************************************************************/
379
380	/** NULL-terminated array of supported file extensions. */
381	static const char *const s_apszVciFileExtensions[] =
382	{
383	"vci",
384	NULL
385	};
386
387	/*******************************************************************************
388	* Internal Functions *
389	*******************************************************************************/
390
391	/**
392	* Internal. Flush image data to disk.
393	*/
394	static int vciFlushImage(PVCICACHE pCache)
395	{
396	int rc = VINF_SUCCESS;
397
398	if ( pCache->pStorage
399	&& !(pCache->uOpenFlags & VD_OPEN_FLAGS_READONLY))
400	{
401	rc = vdIfIoIntFileFlushSync(pCache->pIfIo, pCache->pStorage);
402	}
403
404	return rc;
405	}
406
407	/**
408	* Internal. Free all allocated space for representing an image except pCache,
409	* and optionally delete the image from disk.
410	*/
411	static int vciFreeImage(PVCICACHE pCache, bool fDelete)
412	{
413	int rc = VINF_SUCCESS;
414
415	/* Freeing a never allocated image (e.g. because the open failed) is
416	* not signalled as an error. After all nothing bad happens. */
417	if (pCache)
418	{
419	if (pCache->pStorage)
420	{
421	/* No point updating the file that is deleted anyway. */
422	if (!fDelete)
423	vciFlushImage(pCache);
424
425	vdIfIoIntFileClose(pCache->pIfIo, pCache->pStorage);
426	pCache->pStorage = NULL;
427	}
428
429	if (fDelete && pCache->pszFilename)
430	vdIfIoIntFileDelete(pCache->pIfIo, pCache->pszFilename);
431	}
432
433	LogFlowFunc(("returns %Rrc\n", rc));
434	return rc;
435	}
436
437	/**
438	* Creates a new block map which can manage the given number of blocks.
439	*
440	* The size of the bitmap is aligned to the VCI block size.
441	*
442	* @returns VBox status code.
443	* @param cBlocks The number of blocks the bitmap can manage.
444	* @param ppBlkMap Where to store the pointer to the block bitmap.
445	* @param pcbBlkMap Where to store the size of the block bitmap in blocks
446	* needed on the disk.
447	*/
448	static int vciBlkMapCreate(uint64_t cBlocks, PVCIBLKMAP ppBlkMap, uint32_t pcBlkMap)
449	{
450	int rc = VINF_SUCCESS;
451	uint32_t cbBlkMap = RT_ALIGN_Z(cBlocks / sizeof(VciBlkMapEnt) / 8, VCI_BLOCK_SIZE);
452	PVCIBLKMAP pBlkMap = (PVCIBLKMAP)RTMemAllocZ(sizeof(VCIBLKMAP));
453	PVCIBLKRANGEDESC pFree = (PVCIBLKRANGEDESC)RTMemAllocZ(sizeof(VCIBLKRANGEDESC));
454
455	LogFlowFunc(("cBlocks=%u ppBlkMap=%#p pcBlkMap=%#p\n", cBlocks, ppBlkMap, pcBlkMap));
456
457	if (pBlkMap && pFree)
458	{
459	pBlkMap->cBlocks = cBlocks;
460	pBlkMap->cBlocksAllocMeta = 0;
461	pBlkMap->cBlocksAllocData = 0;
462	pBlkMap->cBlocksFree = cBlocks;
463
464	pFree->pPrev = NULL;
465	pFree->pNext = NULL;
466	pFree->offAddrStart = 0;
467	pFree->cBlocks = cBlocks;
468	pFree->fFree = true;
469
470	pBlkMap->pRangesHead = pFree;
471	pBlkMap->pRangesTail = pFree;
472
473	Assert(!((cbBlkMap + sizeof(VciBlkMap)) % VCI_BLOCK_SIZE));
474	*ppBlkMap = pBlkMap;
475	*pcBlkMap = VCI_BYTE2BLOCK(cbBlkMap + sizeof(VciBlkMap));
476	}
477	else
478	{
479	if (pBlkMap)
480	RTMemFree(pBlkMap);
481	if (pFree)
482	RTMemFree(pFree);
483
484	rc = VERR_NO_MEMORY;
485	}
486
487	LogFlowFunc(("returns rc=%Rrc cBlkMap=%u\n", rc, *pcBlkMap));
488	return rc;
489	}
490
491	/**
492	* Frees a block map.
493	*
494	* @returns nothing.
495	* @param pBlkMap The block bitmap to destroy.
496	*/
497	static void vciBlkMapDestroy(PVCIBLKMAP pBlkMap)
498	{
499	LogFlowFunc(("pBlkMap=%#p\n", pBlkMap));
500
501	PVCIBLKRANGEDESC pRangeCur = pBlkMap->pRangesHead;
502
503	while (pRangeCur)
504	{
505	PVCIBLKRANGEDESC pTmp = pRangeCur;
506
507	RTMemFree(pTmp);
508
509	pRangeCur = pRangeCur->pNext;
510	}
511
512	RTMemFree(pBlkMap);
513
514	LogFlowFunc(("returns\n"));
515	}
516
517	/**
518	* Loads the block map from the specified medium and creates all necessary
519	* in memory structures to manage used and free blocks.
520	*
521	* @returns VBox status code.
522	* @param pStorage Storage handle to read the block bitmap from.
523	* @param offBlkMap Start of the block bitmap in blocks.
524	* @param cBlkMap Size of the block bitmap on the disk in blocks.
525	* @param ppBlkMap Where to store the block bitmap on success.
526	*/
527	static int vciBlkMapLoad(PVCICACHE pStorage, uint64_t offBlkMap, uint32_t cBlkMap, PVCIBLKMAP *ppBlkMap)
528	{
529	int rc = VINF_SUCCESS;
530	VciBlkMap BlkMap;
531
532	LogFlowFunc(("pStorage=%#p offBlkMap=%llu cBlkMap=%u ppBlkMap=%#p\n",
533	pStorage, offBlkMap, cBlkMap, ppBlkMap));
534
535	if (cBlkMap >= VCI_BYTE2BLOCK(sizeof(VciBlkMap)))
536	{
537	cBlkMap -= VCI_BYTE2BLOCK(sizeof(VciBlkMap));
538
539	rc = vdIfIoIntFileReadSync(pStorage->pIfIo, pStorage->pStorage, offBlkMap,
540	&BlkMap, VCI_BYTE2BLOCK(sizeof(VciBlkMap)));
541	if (RT_SUCCESS(rc))
542	{
543	offBlkMap += VCI_BYTE2BLOCK(sizeof(VciBlkMap));
544
545	BlkMap.u32Magic = RT_LE2H_U32(BlkMap.u32Magic);
546	BlkMap.u32Version = RT_LE2H_U32(BlkMap.u32Version);
547	BlkMap.cBlocks = RT_LE2H_U32(BlkMap.cBlocks);
548	BlkMap.cBlocksFree = RT_LE2H_U32(BlkMap.cBlocksFree);
549	BlkMap.cBlocksAllocMeta = RT_LE2H_U32(BlkMap.cBlocksAllocMeta);
550	BlkMap.cBlocksAllocData = RT_LE2H_U32(BlkMap.cBlocksAllocData);
551
552	if ( BlkMap.u32Magic == VCI_BLKMAP_MAGIC
553	&& BlkMap.u32Version == VCI_BLKMAP_VERSION
554	&& BlkMap.cBlocks == BlkMap.cBlocksFree + BlkMap.cBlocksAllocMeta + BlkMap.cBlocksAllocData
555	&& VCI_BYTE2BLOCK(BlkMap.cBlocks / 8) == cBlkMap)
556	{
557	PVCIBLKMAP pBlkMap = (PVCIBLKMAP)RTMemAllocZ(sizeof(VCIBLKMAP));
558	if (pBlkMap)
559	{
560	pBlkMap->cBlocks = BlkMap.cBlocks;
561	pBlkMap->cBlocksFree = BlkMap.cBlocksFree;
562	pBlkMap->cBlocksAllocMeta = BlkMap.cBlocksAllocMeta;
563	pBlkMap->cBlocksAllocData = BlkMap.cBlocksAllocData;
564
565	/* Load the bitmap and construct the range list. */
566	uint32_t cBlocksFree = 0;
567	uint32_t cBlocksAllocated = 0;
568	PVCIBLKRANGEDESC pRangeCur = (PVCIBLKRANGEDESC)RTMemAllocZ(sizeof(VCIBLKRANGEDESC));
569
570	if (pRangeCur)
571	{
572	uint8_t abBitmapBuffer[16 * _1K];
573	uint32_t cBlocksRead = 0;
574	uint64_t cBlocksLeft = VCI_BYTE2BLOCK(pBlkMap->cBlocks / 8);
575
576	cBlocksRead = RT_MIN(VCI_BYTE2BLOCK(sizeof(abBitmapBuffer)), cBlocksLeft);
577	rc = vdIfIoIntFileReadSync(pStorage->pIfIo, pStorage->pStorage,
578	offBlkMap, abBitmapBuffer,
579	cBlocksRead);
580
581	if (RT_SUCCESS(rc))
582	{
583	pRangeCur->fFree = !(abBitmapBuffer[0] & 0x01);
584	pRangeCur->offAddrStart = 0;
585	pRangeCur->cBlocks = 0;
586	pRangeCur->pNext = NULL;
587	pRangeCur->pPrev = NULL;
588	pBlkMap->pRangesHead = pRangeCur;
589	pBlkMap->pRangesTail = pRangeCur;
590	}
591
592	while ( RT_SUCCESS(rc)
593	&& cBlocksLeft)
594	{
595	int iBit = 0;
596	uint32_t cBits = VCI_BLOCK2BYTE(cBlocksRead) * 8;
597	uint32_t iBitPrev = 0xffffffff;
598
599	while (cBits)
600	{
601	if (pRangeCur->fFree)
602	{
603	/* Check for the first set bit. */
604	iBit = ASMBitNextSet(abBitmapBuffer, cBits, iBitPrev);
605	}
606	else
607	{
608	/* Check for the first free bit. */
609	iBit = ASMBitNextClear(abBitmapBuffer, cBits, iBitPrev);
610	}
611
612	if (iBit == -1)
613	{
614	/* No change. */
615	pRangeCur->cBlocks += cBits;
616	cBits = 0;
617	}
618	else
619	{
620	Assert((uint32_t)iBit < cBits);
621	pRangeCur->cBlocks += iBit;
622
623	/* Create a new range descriptor. */
624	PVCIBLKRANGEDESC pRangeNew = (PVCIBLKRANGEDESC)RTMemAllocZ(sizeof(VCIBLKRANGEDESC));
625	if (!pRangeNew)
626	{
627	rc = VERR_NO_MEMORY;
628	break;
629	}
630
631	pRangeNew->fFree = !pRangeCur->fFree;
632	pRangeNew->offAddrStart = pRangeCur->offAddrStart + pRangeCur->cBlocks;
633	pRangeNew->cBlocks = 0;
634	pRangeNew->pPrev = pRangeCur;
635	pRangeCur->pNext = pRangeNew;
636	pBlkMap->pRangesTail = pRangeNew;
637	pRangeCur = pRangeNew;
638	cBits -= iBit;
639	iBitPrev = iBit;
640	}
641	}
642
643	cBlocksLeft -= cBlocksRead;
644	offBlkMap += cBlocksRead;
645
646	if ( RT_SUCCESS(rc)
647	&& cBlocksLeft)
648	{
649	/* Read next chunk. */
650	cBlocksRead = RT_MIN(VCI_BYTE2BLOCK(sizeof(abBitmapBuffer)), cBlocksLeft);
651	rc = vdIfIoIntFileReadSync(pStorage->pIfIo, pStorage->pStorage,
652	offBlkMap, abBitmapBuffer, cBlocksRead);
653	}
654	}
655	}
656	else
657	rc = VERR_NO_MEMORY;
658
659	if (RT_SUCCESS(rc))
660	{
661	*ppBlkMap = pBlkMap;
662	LogFlowFunc(("return success\n"));
663	return VINF_SUCCESS;
664	}
665	else
666	RTMemFree(pBlkMap);
667	}
668	else
669	rc = VERR_NO_MEMORY;
670	}
671	else
672	rc = VERR_VD_GEN_INVALID_HEADER;
673	}
674	else if (RT_SUCCESS(rc))
675	rc = VERR_VD_GEN_INVALID_HEADER;
676	}
677	else
678	rc = VERR_VD_GEN_INVALID_HEADER;
679
680	LogFlowFunc(("returns rc=%Rrc\n", rc));
681	return rc;
682	}
683
684	/**
685	* Saves the block map in the cache image. All necessary on disk structures
686	* are written.
687	*
688	* @returns VBox status code.
689	* @param pBlkMap The block bitmap to save.
690	* @param pStorage Where the block bitmap should be written to.
691	* @param offBlkMap Start of the block bitmap in blocks.
692	* @param cBlkMap Size of the block bitmap on the disk in blocks.
693	*/
694	static int vciBlkMapSave(PVCIBLKMAP pBlkMap, PVCICACHE pStorage, uint64_t offBlkMap, uint32_t cBlkMap)
695	{
696	int rc = VINF_SUCCESS;
697	VciBlkMap BlkMap;
698
699	LogFlowFunc(("pBlkMap=%#p pStorage=%#p offBlkMap=%llu cBlkMap=%u\n",
700	pBlkMap, pStorage, offBlkMap, cBlkMap));
701
702	/* Make sure the number of blocks allocated for us match our expectations. */
703	if (VCI_BYTE2BLOCK(pBlkMap->cBlocks / 8) + VCI_BYTE2BLOCK(sizeof(VciBlkMap)) == cBlkMap)
704	{
705	/* Setup the header */
706	memset(&BlkMap, 0, sizeof(VciBlkMap));
707
708	BlkMap.u32Magic = RT_H2LE_U32(VCI_BLKMAP_MAGIC);
709	BlkMap.u32Version = RT_H2LE_U32(VCI_BLKMAP_VERSION);
710	BlkMap.cBlocks = RT_H2LE_U32(pBlkMap->cBlocks);
711	BlkMap.cBlocksFree = RT_H2LE_U32(pBlkMap->cBlocksFree);
712	BlkMap.cBlocksAllocMeta = RT_H2LE_U32(pBlkMap->cBlocksAllocMeta);
713	BlkMap.cBlocksAllocData = RT_H2LE_U32(pBlkMap->cBlocksAllocData);
714
715	rc = vdIfIoIntFileWriteSync(pStorage->pIfIo, pStorage->pStorage, offBlkMap,
716	&BlkMap, VCI_BYTE2BLOCK(sizeof(VciBlkMap)));
717	if (RT_SUCCESS(rc))
718	{
719	uint8_t abBitmapBuffer[16*_1K];
720	unsigned iBit = 0;
721	PVCIBLKRANGEDESC pCur = pBlkMap->pRangesHead;
722
723	offBlkMap += VCI_BYTE2BLOCK(sizeof(VciBlkMap));
724
725	/* Write the descriptor ranges. */
726	while (pCur)
727	{
728	uint64_t cBlocks = pCur->cBlocks;
729
730	while (cBlocks)
731	{
732	uint64_t cBlocksMax = RT_MIN(cBlocks, sizeof(abBitmapBuffer) * 8 - iBit);
733
734	if (pCur->fFree)
735	ASMBitClearRange(abBitmapBuffer, iBit, iBit + cBlocksMax);
736	else
737	ASMBitSetRange(abBitmapBuffer, iBit, iBit + cBlocksMax);
738
739	iBit += cBlocksMax;
740	cBlocks -= cBlocksMax;
741
742	if (iBit == sizeof(abBitmapBuffer) * 8)
743	{
744	/* Buffer is full, write to file and reset. */
745	rc = vdIfIoIntFileWriteSync(pStorage->pIfIo, pStorage->pStorage,
746	offBlkMap, abBitmapBuffer,
747	VCI_BYTE2BLOCK(sizeof(abBitmapBuffer)));
748	if (RT_FAILURE(rc))
749	break;
750
751	offBlkMap += VCI_BYTE2BLOCK(sizeof(abBitmapBuffer));
752	iBit = 0;
753	}
754	}
755
756	pCur = pCur->pNext;
757	}
758
759	Assert(iBit % 8 == 0);
760
761	if (RT_SUCCESS(rc) && iBit)
762	rc = vdIfIoIntFileWriteSync(pStorage->pIfIo, pStorage->pStorage,
763	offBlkMap, abBitmapBuffer, VCI_BYTE2BLOCK(iBit / 8));
764	}
765	}
766	else
767	rc = VERR_INTERNAL_ERROR; /* @todo Better error code. */
768
769	LogFlowFunc(("returns rc=%Rrc\n", rc));
770	return rc;
771	}
772
773	/**
774	* Finds the range block describing the given block address.
775	*
776	* @returns Pointer to the block range descriptor or NULL if none could be found.
777	* @param pBlkMap The block bitmap to search on.
778	* @param offBlockAddr The block address to search for.
779	*/
780	static PVCIBLKRANGEDESC vciBlkMapFindByBlock(PVCIBLKMAP pBlkMap, uint64_t offBlockAddr)
781	{
782	PVCIBLKRANGEDESC pBlk = pBlkMap->pRangesHead;
783
784	while ( pBlk
785	&& pBlk->offAddrStart < offBlockAddr)
786	pBlk = pBlk->pNext;
787
788	return pBlk;
789	}
790
791	/**
792	* Allocates the given number of blocks in the bitmap and returns the start block address.
793	*
794	* @returns VBox status code.
795	* @param pBlkMap The block bitmap to allocate the blocks from.
796	* @param cBlocks How many blocks to allocate.
797	* @param fFlags Allocation flags, comgination of VCIBLKMAP_ALLOC_*.
798	* @param poffBlockAddr Where to store the start address of the allocated region.
799	*/
800	static int vciBlkMapAllocate(PVCIBLKMAP pBlkMap, uint32_t cBlocks, uint32_t fFlags,
801	uint64_t *poffBlockAddr)
802	{
803	PVCIBLKRANGEDESC pBestFit = NULL;
804	PVCIBLKRANGEDESC pCur = NULL;
805	int rc = VINF_SUCCESS;
806
807	LogFlowFunc(("pBlkMap=%#p cBlocks=%u poffBlockAddr=%#p\n",
808	pBlkMap, cBlocks, poffBlockAddr));
809
810	pCur = pBlkMap->pRangesHead;
811
812	while (pCur)
813	{
814	if ( pCur->fFree
815	&& pCur->cBlocks >= cBlocks)
816	{
817	if ( !pBestFit
818	\|\| pCur->cBlocks < pBestFit->cBlocks)
819	{
820	pBestFit = pCur;
821	/* Stop searching if the size is matching exactly. */
822	if (pBestFit->cBlocks == cBlocks)
823	break;
824	}
825	}
826	pCur = pCur->pNext;
827	}
828
829	Assert(!pBestFit \|\| pBestFit->fFree);
830
831	if (pBestFit)
832	{
833	pBestFit->fFree = false;
834
835	if (pBestFit->cBlocks > cBlocks)
836	{
837	/* Create a new free block. */
838	PVCIBLKRANGEDESC pFree = (PVCIBLKRANGEDESC)RTMemAllocZ(sizeof(VCIBLKRANGEDESC));
839
840	if (pFree)
841	{
842	pFree->fFree = true;
843	pFree->cBlocks = pBestFit->cBlocks - cBlocks;
844	pBestFit->cBlocks -= pFree->cBlocks;
845	pFree->offAddrStart = pBestFit->offAddrStart + cBlocks;
846
847	/* Link into the list. */
848	pFree->pNext = pBestFit->pNext;
849	pBestFit->pNext = pFree;
850	pFree->pPrev = pBestFit;
851	if (!pFree->pNext)
852	pBlkMap->pRangesTail = pFree;
853
854	*poffBlockAddr = pBestFit->offAddrStart;
855	}
856	else
857	{
858	rc = VERR_NO_MEMORY;
859	pBestFit->fFree = true;
860	}
861	}
862	}
863	else
864	rc = VERR_VCI_NO_BLOCKS_FREE;
865
866	if (RT_SUCCESS(rc))
867	{
868	if ((fFlags & VCIBLKMAP_ALLOC_MASK) == VCIBLKMAP_ALLOC_DATA)
869	pBlkMap->cBlocksAllocMeta += cBlocks;
870	else
871	pBlkMap->cBlocksAllocData += cBlocks;
872
873	pBlkMap->cBlocksFree -= cBlocks;
874	}
875
876	LogFlowFunc(("returns rc=%Rrc offBlockAddr=%llu\n", rc, *poffBlockAddr));
877	return rc;
878	}
879
880	/**
881	* Try to extend the space of an already allocated block.
882	*
883	* @returns VBox status code.
884	* @param pBlkMap The block bitmap to allocate the blocks from.
885	* @param cBlocksNew How many blocks the extended block should have.
886	* @param offBlockAddrOld The start address of the block to reallocate.
887	* @param poffBlockAddr Where to store the start address of the allocated region.
888	*/
889	static int vciBlkMapRealloc(PVCIBLKMAP pBlkMap, uint32_t cBlocksNew, uint64_t offBlockAddrOld,
890	uint64_t *poffBlockAddr)
891	{
892	int rc = VINF_SUCCESS;
893
894	LogFlowFunc(("pBlkMap=%#p cBlocksNew=%u offBlockAddrOld=%llu poffBlockAddr=%#p\n",
895	pBlkMap, cBlocksNew, offBlockAddrOld, poffBlockAddr));
896
897	AssertMsgFailed(("Implement\n"));
898
899	LogFlowFunc(("returns rc=%Rrc offBlockAddr=%llu\n", rc, *poffBlockAddr));
900	return rc;
901	}
902
903	/**
904	* Frees a range of blocks.
905	*
906	* @returns nothing.
907	* @param pBlkMap The block bitmap.
908	* @param offBlockAddr Address of the first block to free.
909	* @param cBlocks How many blocks to free.
910	* @param fFlags Allocation flags, comgination of VCIBLKMAP_ALLOC_*.
911	*/
912	static void vciBlkMapFree(PVCIBLKMAP pBlkMap, uint64_t offBlockAddr, uint32_t cBlocks,
913	uint32_t fFlags)
914	{
915	PVCIBLKRANGEDESC pBlk;
916
917	LogFlowFunc(("pBlkMap=%#p offBlockAddr=%llu cBlocks=%u\n",
918	pBlkMap, offBlockAddr, cBlocks));
919
920	while (cBlocks)
921	{
922	pBlk = vciBlkMapFindByBlock(pBlkMap, offBlockAddr);
923	AssertPtr(pBlk);
924
925	/* Easy case, the whole block is freed. */
926	if ( pBlk->offAddrStart == offBlockAddr
927	&& pBlk->cBlocks <= cBlocks)
928	{
929	pBlk->fFree = true;
930	cBlocks -= pBlk->cBlocks;
931	offBlockAddr += pBlk->cBlocks;
932
933	/* Check if it is possible to merge free blocks. */
934	if ( pBlk->pPrev
935	&& pBlk->pPrev->fFree)
936	{
937	PVCIBLKRANGEDESC pBlkPrev = pBlk->pPrev;
938
939	Assert(pBlkPrev->offAddrStart + pBlkPrev->cBlocks == pBlk->offAddrStart);
940	pBlkPrev->cBlocks += pBlk->cBlocks;
941	pBlkPrev->pNext = pBlk->pNext;
942	if (pBlk->pNext)
943	pBlk->pNext->pPrev = pBlkPrev;
944	else
945	pBlkMap->pRangesTail = pBlkPrev;
946
947	RTMemFree(pBlk);
948	pBlk = pBlkPrev;
949	}
950
951	/* Now the one to the right. */
952	if ( pBlk->pNext
953	&& pBlk->pNext->fFree)
954	{
955	PVCIBLKRANGEDESC pBlkNext = pBlk->pNext;
956
957	Assert(pBlk->offAddrStart + pBlk->cBlocks == pBlkNext->offAddrStart);
958	pBlk->cBlocks += pBlkNext->cBlocks;
959	pBlk->pNext = pBlkNext->pNext;
960	if (pBlkNext->pNext)
961	pBlkNext->pNext->pPrev = pBlk;
962	else
963	pBlkMap->pRangesTail = pBlk;
964
965	RTMemFree(pBlkNext);
966	}
967	}
968	else
969	{
970	/* The block is intersecting. */
971	AssertMsgFailed(("TODO\n"));
972	}
973	}
974
975	if ((fFlags & VCIBLKMAP_ALLOC_MASK) == VCIBLKMAP_ALLOC_DATA)
976	pBlkMap->cBlocksAllocMeta -= cBlocks;
977	else
978	pBlkMap->cBlocksAllocData -= cBlocks;
979
980	pBlkMap->cBlocksFree += cBlocks;
981
982	LogFlowFunc(("returns\n"));
983	}
984
985	/**
986	* Converts a tree node from the image to the in memory structure.
987	*
988	* @returns Pointer to the in memory tree node.
989	* @param offBlockAddrNode Block address of the node.
990	* @param pNodeImage Pointer to the image representation of the node.
991	*/
992	static PVCITREENODE vciTreeNodeImage2Host(uint64_t offBlockAddrNode, PVciTreeNode pNodeImage)
993	{
994	PVCITREENODE pNode = NULL;
995
996	if (pNodeImage->u8Type == VCI_TREE_NODE_TYPE_LEAF)
997	{
998	PVCITREENODELEAF pLeaf = (PVCITREENODELEAF)RTMemAllocZ(sizeof(VCITREENODELEAF));
999
1000	if (pLeaf)
1001	{
1002	PVciCacheExtent pExtent = (PVciCacheExtent)&pNodeImage->au8Data[0];
1003
1004	pLeaf->Core.u8Type = VCI_TREE_NODE_TYPE_LEAF;
1005
1006	for (unsigned idx = 0; idx < RT_ELEMENTS(pLeaf->aExtents); idx++)
1007	{
1008	pLeaf->aExtents[idx].u64BlockOffset = RT_LE2H_U64(pExtent->u64BlockOffset);
1009	pLeaf->aExtents[idx].u32Blocks = RT_LE2H_U32(pExtent->u32Blocks);
1010	pLeaf->aExtents[idx].u64BlockAddr = RT_LE2H_U64(pExtent->u64BlockAddr);
1011	pExtent++;
1012
1013	if ( pLeaf->aExtents[idx].u32Blocks
1014	&& pLeaf->aExtents[idx].u64BlockAddr)
1015	pLeaf->cUsedNodes++;
1016	}
1017
1018	pNode = &pLeaf->Core;
1019	}
1020	}
1021	else if (pNodeImage->u8Type == VCI_TREE_NODE_TYPE_INTERNAL)
1022	{
1023	PVCITREENODEINT pInt = (PVCITREENODEINT)RTMemAllocZ(sizeof(VCITREENODEINT));
1024
1025	if (pInt)
1026	{
1027	PVciTreeNodeInternal pIntImage = (PVciTreeNodeInternal)&pNodeImage->au8Data[0];
1028
1029	pInt->Core.u8Type = VCI_TREE_NODE_TYPE_INTERNAL;
1030
1031	for (unsigned idx = 0; idx < RT_ELEMENTS(pInt->aIntNodes); idx++)
1032	{
1033	pInt->aIntNodes[idx].u64BlockOffset = RT_LE2H_U64(pIntImage->u64BlockOffset);
1034	pInt->aIntNodes[idx].u32Blocks = RT_LE2H_U32(pIntImage->u32Blocks);
1035	pInt->aIntNodes[idx].PtrChild.fInMemory = false;
1036	pInt->aIntNodes[idx].PtrChild.u.offAddrBlockNode = RT_LE2H_U64(pIntImage->u64ChildAddr);
1037	pIntImage++;
1038
1039	if ( pInt->aIntNodes[idx].u32Blocks
1040	&& pInt->aIntNodes[idx].PtrChild.u.offAddrBlockNode)
1041	pInt->cUsedNodes++;
1042	}
1043
1044	pNode = &pInt->Core;
1045	}
1046	}
1047	else
1048	AssertMsgFailed(("Invalid node type %d\n", pNodeImage->u8Type));
1049
1050	if (pNode)
1051	pNode->u64BlockAddr = offBlockAddrNode;
1052
1053	return pNode;
1054	}
1055
1056	/**
1057	* Looks up the cache extent for the given virtual block address.
1058	*
1059	* @returns Pointer to the cache extent or NULL if none could be found.
1060	* @param pCache The cache image instance.
1061	* @param offBlockOffset The block offset to search for.
1062	* @param ppNextBestFit Where to store the pointer to the next best fit
1063	* cache extent above offBlockOffset if existing. - Optional
1064	* This is always filled if possible even if the function returns NULL.
1065	*/
1066	static PVCICACHEEXTENT vciCacheExtentLookup(PVCICACHE pCache, uint64_t offBlockOffset,
1067	PVCICACHEEXTENT *ppNextBestFit)
1068	{
1069	int rc = VINF_SUCCESS;
1070	PVCICACHEEXTENT pExtent = NULL;
1071	PVCITREENODE pNodeCur = pCache->pRoot;
1072
1073	while ( RT_SUCCESS(rc)
1074	&& pNodeCur
1075	&& pNodeCur->u8Type != VCI_TREE_NODE_TYPE_LEAF)
1076	{
1077	PVCITREENODEINT pNodeInt = (PVCITREENODEINT)pNodeCur;
1078
1079	Assert(pNodeCur->u8Type == VCI_TREE_NODE_TYPE_INTERNAL);
1080
1081	/* Search for the correct internal node. */
1082	unsigned idxMin = 0;
1083	unsigned idxMax = pNodeInt->cUsedNodes;
1084	unsigned idxCur = pNodeInt->cUsedNodes / 2;
1085
1086	while (idxMin < idxMax)
1087	{
1088	PVCINODEINTERNAL pInt = &pNodeInt->aIntNodes[idxCur];
1089
1090	/* Determine the search direction. */
1091	if (offBlockOffset < pInt->u64BlockOffset)
1092	{
1093	/* Search left from the current extent. */
1094	idxMax = idxCur;
1095	}
1096	else if (offBlockOffset >= pInt->u64BlockOffset + pInt->u32Blocks)
1097	{
1098	/* Search right from the current extent. */
1099	idxMin = idxCur;
1100	}
1101	else
1102	{
1103	/* The block lies in the node, stop searching. */
1104	if (pInt->PtrChild.fInMemory)
1105	pNodeCur = pInt->PtrChild.u.pNode;
1106	else
1107	{
1108	PVCITREENODE pNodeNew;
1109	VciTreeNode NodeTree;
1110
1111	/* Read from disk and add to the tree. */
1112	rc = vdIfIoIntFileReadSync(pCache->pIfIo, pCache->pStorage,
1113	VCI_BLOCK2BYTE(pInt->PtrChild.u.offAddrBlockNode),
1114	&NodeTree, sizeof(NodeTree));
1115	AssertRC(rc);
1116
1117	pNodeNew = vciTreeNodeImage2Host(pInt->PtrChild.u.offAddrBlockNode, &NodeTree);
1118	if (pNodeNew)
1119	{
1120	/* Link to the parent. */
1121	pInt->PtrChild.fInMemory = true;
1122	pInt->PtrChild.u.pNode = pNodeNew;
1123	pNodeNew->pParent = pNodeCur;
1124	pNodeCur = pNodeNew;
1125	}
1126	else
1127	rc = VERR_NO_MEMORY;
1128	}
1129	break;
1130	}
1131
1132	idxCur = idxMin + (idxMax - idxMin) / 2;
1133	}
1134	}
1135
1136	if ( RT_SUCCESS(rc)
1137	&& pNodeCur)
1138	{
1139	PVCITREENODELEAF pLeaf = (PVCITREENODELEAF)pNodeCur;
1140	Assert(pNodeCur->u8Type == VCI_TREE_NODE_TYPE_LEAF);
1141
1142	/* Search the range. */
1143	unsigned idxMin = 0;
1144	unsigned idxMax = pLeaf->cUsedNodes;
1145	unsigned idxCur = pLeaf->cUsedNodes / 2;
1146
1147	while (idxMin < idxMax)
1148	{
1149	PVCICACHEEXTENT pExtentCur = &pLeaf->aExtents[idxCur];
1150
1151	/* Determine the search direction. */
1152	if (offBlockOffset < pExtentCur->u64BlockOffset)
1153	{
1154	/* Search left from the current extent. */
1155	idxMax = idxCur;
1156	}
1157	else if (offBlockOffset >= pExtentCur->u64BlockOffset + pExtentCur->u32Blocks)
1158	{
1159	/* Search right from the current extent. */
1160	idxMin = idxCur;
1161	}
1162	else
1163	{
1164	/* We found the extent, stop searching. */
1165	pExtent = pExtentCur;
1166	break;
1167	}
1168
1169	idxCur = idxMin + (idxMax - idxMin) / 2;
1170	}
1171
1172	/* Get the next best fit extent if it exists. */
1173	if (ppNextBestFit)
1174	{
1175	if (idxCur < pLeaf->cUsedNodes - 1)
1176	*ppNextBestFit = &pLeaf->aExtents[idxCur + 1];
1177	else
1178	{
1179	/*
1180	* Go up the tree and find the best extent
1181	* in the leftmost tree of the child subtree to the right.
1182	*/
1183	PVCITREENODEINT pInt = (PVCITREENODEINT)pLeaf->Core.pParent;
1184
1185	while (pInt)
1186	{
1187
1188	}
1189	}
1190	}
1191	}
1192
1193	return pExtent;
1194	}
1195
1196	/**
1197	* Internal: Open an image, constructing all necessary data structures.
1198	*/
1199	static int vciOpenImage(PVCICACHE pCache, unsigned uOpenFlags)
1200	{
1201	VciHdr Hdr;
1202	uint64_t cbFile;
1203	int rc;
1204
1205	pCache->uOpenFlags = uOpenFlags;
1206
1207	pCache->pIfError = VDIfErrorGet(pCache->pVDIfsDisk);
1208	pCache->pIfIo = VDIfIoIntGet(pCache->pVDIfsImage);
1209	AssertPtrReturn(pCache->pIfIo, VERR_INVALID_PARAMETER);
1210
1211	/*
1212	* Open the image.
1213	*/
1214	rc = vdIfIoIntFileOpen(pCache->pIfIo, pCache->pszFilename,
1215	VDOpenFlagsToFileOpenFlags(uOpenFlags,
1216	false /* fCreate */),
1217	&pCache->pStorage);
1218	if (RT_FAILURE(rc))
1219	{
1220	/* Do NOT signal an appropriate error here, as the VD layer has the
1221	* choice of retrying the open if it failed. */
1222	goto out;
1223	}
1224
1225	rc = vdIfIoIntFileGetSize(pCache->pIfIo, pCache->pStorage, &cbFile);
1226	if (RT_FAILURE(rc) \|\| cbFile < sizeof(VciHdr))
1227	{
1228	rc = VERR_VD_GEN_INVALID_HEADER;
1229	goto out;
1230	}
1231
1232	rc = vdIfIoIntFileReadSync(pCache->pIfIo, pCache->pStorage, 0, &Hdr,
1233	VCI_BYTE2BLOCK(sizeof(Hdr)));
1234	if (RT_FAILURE(rc))
1235	{
1236	rc = VERR_VD_GEN_INVALID_HEADER;
1237	goto out;
1238	}
1239
1240	Hdr.u32Signature = RT_LE2H_U32(Hdr.u32Signature);
1241	Hdr.u32Version = RT_LE2H_U32(Hdr.u32Version);
1242	Hdr.cBlocksCache = RT_LE2H_U64(Hdr.cBlocksCache);
1243	Hdr.u32CacheType = RT_LE2H_U32(Hdr.u32CacheType);
1244	Hdr.offTreeRoot = RT_LE2H_U64(Hdr.offTreeRoot);
1245	Hdr.offBlkMap = RT_LE2H_U64(Hdr.offBlkMap);
1246	Hdr.cBlkMap = RT_LE2H_U32(Hdr.cBlkMap);
1247
1248	if ( Hdr.u32Signature == VCI_HDR_SIGNATURE
1249	&& Hdr.u32Version == VCI_HDR_VERSION)
1250	{
1251	pCache->offTreeRoot = Hdr.offTreeRoot;
1252	pCache->offBlksBitmap = Hdr.offBlkMap;
1253
1254	/* Load the block map. */
1255	rc = vciBlkMapLoad(pCache, pCache->offBlksBitmap, Hdr.cBlkMap, &pCache->pBlkMap);
1256	if (RT_SUCCESS(rc))
1257	{
1258	/* Load the first tree node. */
1259	VciTreeNode RootNode;
1260
1261	rc = vdIfIoIntFileReadSync(pCache->pIfIo, pCache->pStorage,
1262	pCache->offTreeRoot, &RootNode,
1263	VCI_BYTE2BLOCK(sizeof(VciTreeNode)));
1264	if (RT_SUCCESS(rc))
1265	{
1266	pCache->pRoot = vciTreeNodeImage2Host(pCache->offTreeRoot, &RootNode);
1267	if (!pCache->pRoot)
1268	rc = VERR_NO_MEMORY;
1269	}
1270	}
1271	}
1272	else
1273	rc = VERR_VD_GEN_INVALID_HEADER;
1274
1275	out:
1276	if (RT_FAILURE(rc))
1277	vciFreeImage(pCache, false);
1278	return rc;
1279	}
1280
1281	/**
1282	* Internal: Create a vci image.
1283	*/
1284	static int vciCreateImage(PVCICACHE pCache, uint64_t cbSize,
1285	unsigned uImageFlags, const char *pszComment,
1286	unsigned uOpenFlags, PFNVDPROGRESS pfnProgress,
1287	void *pvUser, unsigned uPercentStart,
1288	unsigned uPercentSpan)
1289	{
1290	VciHdr Hdr;
1291	VciTreeNode NodeRoot;
1292	int rc;
1293	uint64_t cBlocks = cbSize / VCI_BLOCK_SIZE; /* Size of the cache in blocks. */
1294
1295	pCache->uImageFlags = uImageFlags;
1296	pCache->uOpenFlags = uOpenFlags & ~VD_OPEN_FLAGS_READONLY;
1297
1298	pCache->pIfError = VDIfErrorGet(pCache->pVDIfsDisk);
1299	pCache->pIfIo = VDIfIoIntGet(pCache->pVDIfsImage);
1300	AssertPtrReturn(pCache->pIfIo, VERR_INVALID_PARAMETER);
1301
1302	if (uImageFlags & VD_IMAGE_FLAGS_DIFF)
1303	{
1304	rc = vdIfError(pCache->pIfError, VERR_VD_RAW_INVALID_TYPE, RT_SRC_POS, N_("VCI: cannot create diff image '%s'"), pCache->pszFilename);
1305	return rc;
1306	}
1307
1308	do
1309	{
1310	/* Create image file. */
1311	rc = vdIfIoIntFileOpen(pCache->pIfIo, pCache->pszFilename,
1312	VDOpenFlagsToFileOpenFlags(uOpenFlags & ~VD_OPEN_FLAGS_READONLY,
1313	true /* fCreate */),
1314	&pCache->pStorage);
1315	if (RT_FAILURE(rc))
1316	{
1317	rc = vdIfError(pCache->pIfError, rc, RT_SRC_POS, N_("VCI: cannot create image '%s'"), pCache->pszFilename);
1318	break;
1319	}
1320
1321	/* Allocate block bitmap. */
1322	uint32_t cBlkMap = 0;
1323	rc = vciBlkMapCreate(cBlocks, &pCache->pBlkMap, &cBlkMap);
1324	if (RT_FAILURE(rc))
1325	{
1326	rc = vdIfError(pCache->pIfError, rc, RT_SRC_POS, N_("VCI: cannot create block bitmap '%s'"), pCache->pszFilename);
1327	break;
1328	}
1329
1330	/*
1331	* Allocate space for the header in the block bitmap.
1332	* Because the block map is empty the header has to start at block 0
1333	*/
1334	uint64_t offHdr = 0;
1335	rc = vciBlkMapAllocate(pCache->pBlkMap, VCI_BYTE2BLOCK(sizeof(VciHdr)), VCIBLKMAP_ALLOC_META, &offHdr);
1336	if (RT_FAILURE(rc))
1337	{
1338	rc = vdIfError(pCache->pIfError, rc, RT_SRC_POS, N_("VCI: cannot allocate space for header in block bitmap '%s'"), pCache->pszFilename);
1339	break;
1340	}
1341
1342	Assert(offHdr == 0);
1343
1344	/*
1345	* Allocate space for the block map itself.
1346	*/
1347	uint64_t offBlkMap = 0;
1348	rc = vciBlkMapAllocate(pCache->pBlkMap, cBlkMap, VCIBLKMAP_ALLOC_META, &offBlkMap);
1349	if (RT_FAILURE(rc))
1350	{
1351	rc = vdIfError(pCache->pIfError, rc, RT_SRC_POS, N_("VCI: cannot allocate space for block map in block map '%s'"), pCache->pszFilename);
1352	break;
1353	}
1354
1355	/*
1356	* Allocate space for the tree root node.
1357	*/
1358	uint64_t offTreeRoot = 0;
1359	rc = vciBlkMapAllocate(pCache->pBlkMap, VCI_BYTE2BLOCK(sizeof(VciTreeNode)), VCIBLKMAP_ALLOC_META, &offTreeRoot);
1360	if (RT_FAILURE(rc))
1361	{
1362	rc = vdIfError(pCache->pIfError, rc, RT_SRC_POS, N_("VCI: cannot allocate space for block map in block map '%s'"), pCache->pszFilename);
1363	break;
1364	}
1365
1366	/*
1367	* Allocate the in memory root node.
1368	*/
1369	pCache->pRoot = (PVCITREENODE)RTMemAllocZ(sizeof(VCITREENODELEAF));
1370	if (!pCache->pRoot)
1371	{
1372	rc = vdIfError(pCache->pIfError, rc, RT_SRC_POS, N_("VCI: cannot allocate B+-Tree root pointer '%s'"), pCache->pszFilename);
1373	break;
1374	}
1375
1376	pCache->pRoot->u8Type = VCI_TREE_NODE_TYPE_LEAF;
1377	/* Rest remains 0 as the tree is still empty. */
1378
1379	/*
1380	* Now that we are here we have all the basic structures and know where to place them in the image.
1381	* It's time to write it now.
1382	*/
1383
1384	/* Setup the header. */
1385	memset(&Hdr, 0, sizeof(VciHdr));
1386	Hdr.u32Signature = RT_H2LE_U32(VCI_HDR_SIGNATURE);
1387	Hdr.u32Version = RT_H2LE_U32(VCI_HDR_VERSION);
1388	Hdr.cBlocksCache = RT_H2LE_U64(cBlocks);
1389	Hdr.fUncleanShutdown = VCI_HDR_UNCLEAN_SHUTDOWN;
1390	Hdr.u32CacheType = uImageFlags & VD_IMAGE_FLAGS_FIXED
1391	? RT_H2LE_U32(VCI_HDR_CACHE_TYPE_FIXED)
1392	: RT_H2LE_U32(VCI_HDR_CACHE_TYPE_DYNAMIC);
1393	Hdr.offTreeRoot = RT_H2LE_U64(offTreeRoot);
1394	Hdr.offBlkMap = RT_H2LE_U64(offBlkMap);
1395	Hdr.cBlkMap = RT_H2LE_U32(cBlkMap);
1396
1397	rc = vdIfIoIntFileWriteSync(pCache->pIfIo, pCache->pStorage, offHdr, &Hdr,
1398	VCI_BYTE2BLOCK(sizeof(VciHdr)));
1399	if (RT_FAILURE(rc))
1400	{
1401	rc = vdIfError(pCache->pIfError, rc, RT_SRC_POS, N_("VCI: cannot write header '%s'"), pCache->pszFilename);
1402	break;
1403	}
1404
1405	rc = vciBlkMapSave(pCache->pBlkMap, pCache, offBlkMap, cBlkMap);
1406	if (RT_FAILURE(rc))
1407	{
1408	rc = vdIfError(pCache->pIfError, rc, RT_SRC_POS, N_("VCI: cannot write block map '%s'"), pCache->pszFilename);
1409	break;
1410	}
1411
1412	/* Setup the root tree. */
1413	memset(&NodeRoot, 0, sizeof(VciTreeNode));
1414	NodeRoot.u8Type = RT_H2LE_U32(VCI_TREE_NODE_TYPE_LEAF);
1415
1416	rc = vdIfIoIntFileWriteSync(pCache->pIfIo, pCache->pStorage, offTreeRoot,
1417	&NodeRoot, VCI_BYTE2BLOCK(sizeof(VciTreeNode)));
1418	if (RT_FAILURE(rc))
1419	{
1420	rc = vdIfError(pCache->pIfError, rc, RT_SRC_POS, N_("VCI: cannot write root node '%s'"), pCache->pszFilename);
1421	break;
1422	}
1423
1424	rc = vciFlushImage(pCache);
1425	if (RT_FAILURE(rc))
1426	{
1427	rc = vdIfError(pCache->pIfError, rc, RT_SRC_POS, N_("VCI: cannot flush '%s'"), pCache->pszFilename);
1428	break;
1429	}
1430
1431	pCache->cbSize = cbSize;
1432
1433	} while (0);
1434
1435	if (RT_SUCCESS(rc) && pfnProgress)
1436	pfnProgress(pvUser, uPercentStart + uPercentSpan);
1437
1438	if (RT_FAILURE(rc))
1439	vciFreeImage(pCache, rc != VERR_ALREADY_EXISTS);
1440	return rc;
1441	}
1442
1443	/** @copydoc VDCACHEBACKEND::pfnProbe */
1444	static int vciProbe(const char *pszFilename, PVDINTERFACE pVDIfsCache,
1445	PVDINTERFACE pVDIfsImage)
1446	{
1447	VciHdr Hdr;
1448	PVDIOSTORAGE pStorage = NULL;
1449	uint64_t cbFile;
1450	int rc = VINF_SUCCESS;
1451
1452	LogFlowFunc(("pszFilename=\"%s\"\n", pszFilename));
1453
1454	PVDINTERFACEIOINT pIfIo = VDIfIoIntGet(pVDIfsImage);
1455	AssertPtrReturn(pIfIo, VERR_INVALID_PARAMETER);
1456
1457	rc = vdIfIoIntFileOpen(pIfIo, pszFilename,
1458	VDOpenFlagsToFileOpenFlags(VD_OPEN_FLAGS_READONLY,
1459	false /* fCreate */),
1460	&pStorage);
1461	if (RT_FAILURE(rc))
1462	goto out;
1463
1464	rc = vdIfIoIntFileGetSize(pIfIo, pStorage, &cbFile);
1465	if (RT_FAILURE(rc) \|\| cbFile < sizeof(VciHdr))
1466	{
1467	rc = VERR_VD_GEN_INVALID_HEADER;
1468	goto out;
1469	}
1470
1471	rc = vdIfIoIntFileReadSync(pIfIo, pStorage, 0, &Hdr, sizeof(Hdr));
1472	if (RT_FAILURE(rc))
1473	{
1474	rc = VERR_VD_GEN_INVALID_HEADER;
1475	goto out;
1476	}
1477
1478	Hdr.u32Signature = RT_LE2H_U32(Hdr.u32Signature);
1479	Hdr.u32Version = RT_LE2H_U32(Hdr.u32Version);
1480	Hdr.cBlocksCache = RT_LE2H_U64(Hdr.cBlocksCache);
1481	Hdr.u32CacheType = RT_LE2H_U32(Hdr.u32CacheType);
1482	Hdr.offTreeRoot = RT_LE2H_U64(Hdr.offTreeRoot);
1483	Hdr.offBlkMap = RT_LE2H_U64(Hdr.offBlkMap);
1484	Hdr.cBlkMap = RT_LE2H_U32(Hdr.cBlkMap);
1485
1486	if ( Hdr.u32Signature == VCI_HDR_SIGNATURE
1487	&& Hdr.u32Version == VCI_HDR_VERSION)
1488	rc = VINF_SUCCESS;
1489	else
1490	rc = VERR_VD_GEN_INVALID_HEADER;
1491
1492	out:
1493	if (pStorage)
1494	vdIfIoIntFileClose(pIfIo, pStorage);
1495
1496	LogFlowFunc(("returns %Rrc\n", rc));
1497	return rc;
1498	}
1499
1500	/** @copydoc VDCACHEBACKEND::pfnOpen */
1501	static int vciOpen(const char *pszFilename, unsigned uOpenFlags,
1502	PVDINTERFACE pVDIfsDisk, PVDINTERFACE pVDIfsImage,
1503	void **ppBackendData)
1504	{
1505	LogFlowFunc(("pszFilename=\"%s\" uOpenFlags=%#x pVDIfsDisk=%#p pVDIfsImage=%#p ppBackendData=%#p\n", pszFilename, uOpenFlags, pVDIfsDisk, pVDIfsImage, ppBackendData));
1506	int rc;
1507	PVCICACHE pCache;
1508
1509	/* Check open flags. All valid flags are supported. */
1510	if (uOpenFlags & ~VD_OPEN_FLAGS_MASK)
1511	{
1512	rc = VERR_INVALID_PARAMETER;
1513	goto out;
1514	}
1515
1516	/* Check remaining arguments. */
1517	if ( !VALID_PTR(pszFilename)
1518	\|\| !*pszFilename)
1519	{
1520	rc = VERR_INVALID_PARAMETER;
1521	goto out;
1522	}
1523
1524
1525	pCache = (PVCICACHE)RTMemAllocZ(sizeof(VCICACHE));
1526	if (!pCache)
1527	{
1528	rc = VERR_NO_MEMORY;
1529	goto out;
1530	}
1531	pCache->pszFilename = pszFilename;
1532	pCache->pStorage = NULL;
1533	pCache->pVDIfsDisk = pVDIfsDisk;
1534	pCache->pVDIfsImage = pVDIfsImage;
1535
1536	rc = vciOpenImage(pCache, uOpenFlags);
1537	if (RT_SUCCESS(rc))
1538	*ppBackendData = pCache;
1539	else
1540	RTMemFree(pCache);
1541
1542	out:
1543	LogFlowFunc(("returns %Rrc (pBackendData=%#p)\n", rc, *ppBackendData));
1544	return rc;
1545	}
1546
1547	/** @copydoc VDCACHEBACKEND::pfnCreate */
1548	static int vciCreate(const char *pszFilename, uint64_t cbSize,
1549	unsigned uImageFlags, const char *pszComment,
1550	PCRTUUID pUuid, unsigned uOpenFlags,
1551	unsigned uPercentStart, unsigned uPercentSpan,
1552	PVDINTERFACE pVDIfsDisk, PVDINTERFACE pVDIfsImage,
1553	PVDINTERFACE pVDIfsOperation, void **ppBackendData)
1554	{
1555	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",
1556	pszFilename, cbSize, uImageFlags, pszComment, pUuid, uOpenFlags, uPercentStart, uPercentSpan, pVDIfsDisk, pVDIfsImage, pVDIfsOperation, ppBackendData));
1557	int rc;
1558	PVCICACHE pCache;
1559
1560	PFNVDPROGRESS pfnProgress = NULL;
1561	void *pvUser = NULL;
1562	PVDINTERFACEPROGRESS pIfProgress = VDIfProgressGet(pVDIfsOperation);
1563	if (pIfProgress)
1564	{
1565	pfnProgress = pIfProgress->pfnProgress;
1566	pvUser = pIfProgress->Core.pvUser;
1567	}
1568
1569	/* Check open flags. All valid flags are supported. */
1570	if (uOpenFlags & ~VD_OPEN_FLAGS_MASK)
1571	{
1572	rc = VERR_INVALID_PARAMETER;
1573	goto out;
1574	}
1575
1576	/* Check remaining arguments. */
1577	if ( !VALID_PTR(pszFilename)
1578	\|\| !*pszFilename)
1579	{
1580	rc = VERR_INVALID_PARAMETER;
1581	goto out;
1582	}
1583
1584	pCache = (PVCICACHE)RTMemAllocZ(sizeof(VCICACHE));
1585	if (!pCache)
1586	{
1587	rc = VERR_NO_MEMORY;
1588	goto out;
1589	}
1590	pCache->pszFilename = pszFilename;
1591	pCache->pStorage = NULL;
1592	pCache->pVDIfsDisk = pVDIfsDisk;
1593	pCache->pVDIfsImage = pVDIfsImage;
1594
1595	rc = vciCreateImage(pCache, cbSize, uImageFlags, pszComment, uOpenFlags,
1596	pfnProgress, pvUser, uPercentStart, uPercentSpan);
1597	if (RT_SUCCESS(rc))
1598	{
1599	/* So far the image is opened in read/write mode. Make sure the
1600	* image is opened in read-only mode if the caller requested that. */
1601	if (uOpenFlags & VD_OPEN_FLAGS_READONLY)
1602	{
1603	vciFreeImage(pCache, false);
1604	rc = vciOpenImage(pCache, uOpenFlags);
1605	if (RT_FAILURE(rc))
1606	{
1607	RTMemFree(pCache);
1608	goto out;
1609	}
1610	}
1611	*ppBackendData = pCache;
1612	}
1613	else
1614	RTMemFree(pCache);
1615
1616	out:
1617	LogFlowFunc(("returns %Rrc (pBackendData=%#p)\n", rc, *ppBackendData));
1618	return rc;
1619	}
1620
1621	/** @copydoc VDCACHEBACKEND::pfnClose */
1622	static int vciClose(void *pBackendData, bool fDelete)
1623	{
1624	LogFlowFunc(("pBackendData=%#p fDelete=%d\n", pBackendData, fDelete));
1625	PVCICACHE pCache = (PVCICACHE)pBackendData;
1626	int rc;
1627
1628	rc = vciFreeImage(pCache, fDelete);
1629	RTMemFree(pCache);
1630
1631	LogFlowFunc(("returns %Rrc\n", rc));
1632	return rc;
1633	}
1634
1635	/** @copydoc VDCACHEBACKEND::pfnRead */
1636	static int vciRead(void *pBackendData, uint64_t uOffset, size_t cbToRead,
1637	PVDIOCTX pIoCtx, size_t *pcbActuallyRead)
1638	{
1639	LogFlowFunc(("pBackendData=%#p uOffset=%llu cbToRead=%zu pIoCtx=%#p pcbActuallyRead=%#p\n",
1640	pBackendData, uOffset, cbToRead, pIoCtx, pcbActuallyRead));
1641	PVCICACHE pCache = (PVCICACHE)pBackendData;
1642	int rc = VINF_SUCCESS;
1643	PVCICACHEEXTENT pExtent;
1644	uint64_t cBlocksToRead = VCI_BYTE2BLOCK(cbToRead);
1645	uint64_t offBlockAddr = VCI_BYTE2BLOCK(uOffset);
1646
1647	AssertPtr(pCache);
1648	Assert(uOffset % 512 == 0);
1649	Assert(cbToRead % 512 == 0);
1650
1651	pExtent = vciCacheExtentLookup(pCache, offBlockAddr, NULL);
1652	if (pExtent)
1653	{
1654	uint64_t offRead = offBlockAddr - pExtent->u64BlockOffset;
1655	cBlocksToRead = RT_MIN(cBlocksToRead, pExtent->u32Blocks - offRead);
1656
1657	rc = vdIfIoIntFileReadUser(pCache->pIfIo, pCache->pStorage,
1658	pExtent->u64BlockAddr + offRead,
1659	pIoCtx, cBlocksToRead);
1660	}
1661	else
1662	{
1663	/** @todo Best fit to check whether we have cached data later and set
1664	* pcbActuallyRead accordingly. */
1665	rc = VERR_VD_BLOCK_FREE;
1666	}
1667
1668	if (pcbActuallyRead)
1669	*pcbActuallyRead = VCI_BLOCK2BYTE(cBlocksToRead);
1670
1671	LogFlowFunc(("returns %Rrc\n", rc));
1672	return rc;
1673	}
1674
1675	/** @copydoc VDCACHEBACKEND::pfnWrite */
1676	static int vciWrite(void *pBackendData, uint64_t uOffset, size_t cbToWrite,
1677	PVDIOCTX pIoCtx, size_t *pcbWriteProcess)
1678	{
1679	LogFlowFunc(("pBackendData=%#p uOffset=%llu cbToWrite=%zu pIoCtx=%#p pcbWriteProcess=%#p\n",
1680	pBackendData, uOffset, cbToWrite, pIoCtx, pcbWriteProcess));
1681	PVCICACHE pCache = (PVCICACHE)pBackendData;
1682	int rc = VINF_SUCCESS;
1683	uint64_t cBlocksToWrite = VCI_BYTE2BLOCK(cbToWrite);
1684	uint64_t offBlockAddr = VCI_BYTE2BLOCK(uOffset);
1685
1686	AssertPtr(pCache);
1687	Assert(uOffset % 512 == 0);
1688	Assert(cbToWrite % 512 == 0);
1689
1690	while (cBlocksToWrite)
1691	{
1692
1693	}
1694
1695	pcbWriteProcess = cbToWrite; /* @todo: Implement. */
1696
1697	LogFlowFunc(("returns %Rrc\n", rc));
1698	return rc;
1699	}
1700
1701	/** @copydoc VDCACHEBACKEND::pfnFlush */
1702	static int vciFlush(void *pBackendData, PVDIOCTX pIoCtx)
1703	{
1704	LogFlowFunc(("pBackendData=%#p\n", pBackendData));
1705	PVCICACHE pCache = (PVCICACHE)pBackendData;
1706	int rc = VINF_SUCCESS;
1707
1708	rc = vciFlushImage(pCache);
1709	LogFlowFunc(("returns %Rrc\n", rc));
1710	return rc;
1711	}
1712
1713	/** @copydoc VDCACHEBACKEND::pfnGetVersion */
1714	static unsigned vciGetVersion(void *pBackendData)
1715	{
1716	LogFlowFunc(("pBackendData=%#p\n", pBackendData));
1717	PVCICACHE pCache = (PVCICACHE)pBackendData;
1718
1719	AssertPtr(pCache);
1720
1721	if (pCache)
1722	return 1;
1723	else
1724	return 0;
1725	}
1726
1727	/** @copydoc VDCACHEBACKEND::pfnGetSize */
1728	static uint64_t vciGetSize(void *pBackendData)
1729	{
1730	LogFlowFunc(("pBackendData=%#p\n", pBackendData));
1731	PVCICACHE pCache = (PVCICACHE)pBackendData;
1732	uint64_t cb = 0;
1733
1734	AssertPtr(pCache);
1735
1736	if (pCache && pCache->pStorage)
1737	cb = pCache->cbSize;
1738
1739	LogFlowFunc(("returns %llu\n", cb));
1740	return cb;
1741	}
1742
1743	/** @copydoc VDCACHEBACKEND::pfnGetFileSize */
1744	static uint64_t vciGetFileSize(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)
1753	{
1754	uint64_t cbFile;
1755	if (pCache->pStorage)
1756	{
1757	int rc = vdIfIoIntFileGetSize(pCache->pIfIo, pCache->pStorage, &cbFile);
1758	if (RT_SUCCESS(rc))
1759	cb = cbFile;
1760	}
1761	}
1762
1763	LogFlowFunc(("returns %lld\n", cb));
1764	return cb;
1765	}
1766
1767	/** @copydoc VDCACHEBACKEND::pfnGetImageFlags */
1768	static unsigned vciGetImageFlags(void *pBackendData)
1769	{
1770	LogFlowFunc(("pBackendData=%#p\n", pBackendData));
1771	PVCICACHE pCache = (PVCICACHE)pBackendData;
1772	unsigned uImageFlags;
1773
1774	AssertPtr(pCache);
1775
1776	if (pCache)
1777	uImageFlags = pCache->uImageFlags;
1778	else
1779	uImageFlags = 0;
1780
1781	LogFlowFunc(("returns %#x\n", uImageFlags));
1782	return uImageFlags;
1783	}
1784
1785	/** @copydoc VDCACHEBACKEND::pfnGetOpenFlags */
1786	static unsigned vciGetOpenFlags(void *pBackendData)
1787	{
1788	LogFlowFunc(("pBackendData=%#p\n", pBackendData));
1789	PVCICACHE pCache = (PVCICACHE)pBackendData;
1790	unsigned uOpenFlags;
1791
1792	AssertPtr(pCache);
1793
1794	if (pCache)
1795	uOpenFlags = pCache->uOpenFlags;
1796	else
1797	uOpenFlags = 0;
1798
1799	LogFlowFunc(("returns %#x\n", uOpenFlags));
1800	return uOpenFlags;
1801	}
1802
1803	/** @copydoc VDCACHEBACKEND::pfnSetOpenFlags */
1804	static int vciSetOpenFlags(void *pBackendData, unsigned uOpenFlags)
1805	{
1806	LogFlowFunc(("pBackendData=%#p\n uOpenFlags=%#x", pBackendData, uOpenFlags));
1807	PVCICACHE pCache = (PVCICACHE)pBackendData;
1808	int rc;
1809
1810	/* Image must be opened and the new flags must be valid. Just readonly and
1811	* info flags are supported. */
1812	if (!pCache \|\| (uOpenFlags & ~(VD_OPEN_FLAGS_READONLY \| VD_OPEN_FLAGS_INFO)))
1813	{
1814	rc = VERR_INVALID_PARAMETER;
1815	goto out;
1816	}
1817
1818	/* Implement this operation via reopening the image. */
1819	rc = vciFreeImage(pCache, false);
1820	if (RT_FAILURE(rc))
1821	goto out;
1822	rc = vciOpenImage(pCache, uOpenFlags);
1823
1824	out:
1825	LogFlowFunc(("returns %Rrc\n", rc));
1826	return rc;
1827	}
1828
1829	/** @copydoc VDCACHEBACKEND::pfnGetComment */
1830	static int vciGetComment(void pBackendData, char pszComment,
1831	size_t cbComment)
1832	{
1833	LogFlowFunc(("pBackendData=%#p pszComment=%#p cbComment=%zu\n", pBackendData, pszComment, cbComment));
1834	PVCICACHE pCache = (PVCICACHE)pBackendData;
1835	int rc;
1836
1837	AssertPtr(pCache);
1838
1839	if (pCache)
1840	rc = VERR_NOT_SUPPORTED;
1841	else
1842	rc = VERR_VD_NOT_OPENED;
1843
1844	LogFlowFunc(("returns %Rrc comment='%s'\n", rc, pszComment));
1845	return rc;
1846	}
1847
1848	/** @copydoc VDCACHEBACKEND::pfnSetComment */
1849	static int vciSetComment(void pBackendData, const char pszComment)
1850	{
1851	LogFlowFunc(("pBackendData=%#p pszComment=\"%s\"\n", pBackendData, pszComment));
1852	PVCICACHE pCache = (PVCICACHE)pBackendData;
1853	int rc;
1854
1855	AssertPtr(pCache);
1856
1857	if (pCache)
1858	{
1859	if (pCache->uOpenFlags & VD_OPEN_FLAGS_READONLY)
1860	rc = VERR_VD_IMAGE_READ_ONLY;
1861	else
1862	rc = VERR_NOT_SUPPORTED;
1863	}
1864	else
1865	rc = VERR_VD_NOT_OPENED;
1866
1867	LogFlowFunc(("returns %Rrc\n", rc));
1868	return rc;
1869	}
1870
1871	/** @copydoc VDCACHEBACKEND::pfnGetUuid */
1872	static int vciGetUuid(void *pBackendData, PRTUUID pUuid)
1873	{
1874	LogFlowFunc(("pBackendData=%#p pUuid=%#p\n", pBackendData, pUuid));
1875	PVCICACHE pCache = (PVCICACHE)pBackendData;
1876	int rc;
1877
1878	AssertPtr(pCache);
1879
1880	if (pCache)
1881	rc = VERR_NOT_SUPPORTED;
1882	else
1883	rc = VERR_VD_NOT_OPENED;
1884
1885	LogFlowFunc(("returns %Rrc (%RTuuid)\n", rc, pUuid));
1886	return rc;
1887	}
1888
1889	/** @copydoc VDCACHEBACKEND::pfnSetUuid */
1890	static int vciSetUuid(void *pBackendData, PCRTUUID pUuid)
1891	{
1892	LogFlowFunc(("pBackendData=%#p Uuid=%RTuuid\n", pBackendData, pUuid));
1893	PVCICACHE pCache = (PVCICACHE)pBackendData;
1894	int rc;
1895
1896	LogFlowFunc(("%RTuuid\n", pUuid));
1897	AssertPtr(pCache);
1898
1899	if (pCache)
1900	{
1901	if (!(pCache->uOpenFlags & VD_OPEN_FLAGS_READONLY))
1902	rc = VERR_NOT_SUPPORTED;
1903	else
1904	rc = VERR_VD_IMAGE_READ_ONLY;
1905	}
1906	else
1907	rc = VERR_VD_NOT_OPENED;
1908
1909	LogFlowFunc(("returns %Rrc\n", rc));
1910	return rc;
1911	}
1912
1913	/** @copydoc VDCACHEBACKEND::pfnGetModificationUuid */
1914	static int vciGetModificationUuid(void *pBackendData, PRTUUID pUuid)
1915	{
1916	LogFlowFunc(("pBackendData=%#p pUuid=%#p\n", pBackendData, pUuid));
1917	PVCICACHE pCache = (PVCICACHE)pBackendData;
1918	int rc;
1919
1920	AssertPtr(pCache);
1921
1922	if (pCache)
1923	rc = VERR_NOT_SUPPORTED;
1924	else
1925	rc = VERR_VD_NOT_OPENED;
1926
1927	LogFlowFunc(("returns %Rrc (%RTuuid)\n", rc, pUuid));
1928	return rc;
1929	}
1930
1931	/** @copydoc VDCACHEBACKEND::pfnSetModificationUuid */
1932	static int vciSetModificationUuid(void *pBackendData, PCRTUUID pUuid)
1933	{
1934	LogFlowFunc(("pBackendData=%#p Uuid=%RTuuid\n", pBackendData, pUuid));
1935	PVCICACHE pCache = (PVCICACHE)pBackendData;
1936	int rc;
1937
1938	AssertPtr(pCache);
1939
1940	if (pCache)
1941	{
1942	if (!(pCache->uOpenFlags & VD_OPEN_FLAGS_READONLY))
1943	rc = VERR_NOT_SUPPORTED;
1944	else
1945	rc = VERR_VD_IMAGE_READ_ONLY;
1946	}
1947	else
1948	rc = VERR_VD_NOT_OPENED;
1949
1950	LogFlowFunc(("returns %Rrc\n", rc));
1951	return rc;
1952	}
1953
1954	/** @copydoc VDCACHEBACKEND::pfnDump */
1955	static void vciDump(void *pBackendData)
1956	{
1957	NOREF(pBackendData);
1958	}
1959
1960
1961	const VDCACHEBACKEND g_VciCacheBackend =
1962	{
1963	/* pszBackendName */
1964	"vci",
1965	/* cbSize */
1966	sizeof(VDCACHEBACKEND),
1967	/* uBackendCaps */
1968	VD_CAP_CREATE_FIXED \| VD_CAP_CREATE_DYNAMIC \| VD_CAP_FILE \| VD_CAP_VFS,
1969	/* papszFileExtensions */
1970	s_apszVciFileExtensions,
1971	/* paConfigInfo */
1972	NULL,
1973	/* pfnProbe */
1974	vciProbe,
1975	/* pfnOpen */
1976	vciOpen,
1977	/* pfnCreate */
1978	vciCreate,
1979	/* pfnClose */
1980	vciClose,
1981	/* pfnRead */
1982	vciRead,
1983	/* pfnWrite */
1984	vciWrite,
1985	/* pfnFlush */
1986	vciFlush,
1987	/* pfnDiscard */
1988	NULL,
1989	/* pfnGetVersion */
1990	vciGetVersion,
1991	/* pfnGetSize */
1992	vciGetSize,
1993	/* pfnGetFileSize */
1994	vciGetFileSize,
1995	/* pfnGetImageFlags */
1996	vciGetImageFlags,
1997	/* pfnGetOpenFlags */
1998	vciGetOpenFlags,
1999	/* pfnSetOpenFlags */
2000	vciSetOpenFlags,
2001	/* pfnGetComment */
2002	vciGetComment,
2003	/* pfnSetComment */
2004	vciSetComment,
2005	/* pfnGetUuid */
2006	vciGetUuid,
2007	/* pfnSetUuid */
2008	vciSetUuid,
2009	/* pfnGetModificationUuid */
2010	vciGetModificationUuid,
2011	/* pfnSetModificationUuid */
2012	vciSetModificationUuid,
2013	/* pfnDump */
2014	vciDump,
2015	/* pfnComposeLocation */
2016	NULL,
2017	/* pfnComposeName */
2018	NULL
2019	};
2020

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

source: vbox/trunk/src/VBox/Storage/VCICache.cpp@ 51287

Download in other formats: