xref: /openbmc/u-boot/fs/yaffs2/yaffs_guts.c (revision ae03661f)
1 /*
2  * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
3  *
4  * Copyright (C) 2002-2007 Aleph One Ltd.
5  *   for Toby Churchill Ltd and Brightstar Engineering
6  *
7  * Created by Charles Manning <charles@aleph1.co.uk>
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License version 2 as
11  * published by the Free Software Foundation.
12  */
13 
14 /* XXX U-BOOT XXX */
15 #include <common.h>
16 
17 const char *yaffs_guts_c_version =
18     "$Id: yaffs_guts.c,v 1.52 2007/10/16 00:45:05 charles Exp $";
19 
20 #include "yportenv.h"
21 #include "linux/stat.h"
22 
23 #include "yaffsinterface.h"
24 #include "yaffsfs.h"
25 #include "yaffs_guts.h"
26 #include "yaffs_tagsvalidity.h"
27 
28 #include "yaffs_tagscompat.h"
29 #ifndef  CONFIG_YAFFS_USE_OWN_SORT
30 #include "yaffs_qsort.h"
31 #endif
32 #include "yaffs_nand.h"
33 
34 #include "yaffs_checkptrw.h"
35 
36 #include "yaffs_nand.h"
37 #include "yaffs_packedtags2.h"
38 
39 #include "malloc.h"
40 
41 #ifdef CONFIG_YAFFS_WINCE
42 void yfsd_LockYAFFS(BOOL fsLockOnly);
43 void yfsd_UnlockYAFFS(BOOL fsLockOnly);
44 #endif
45 
46 #define YAFFS_PASSIVE_GC_CHUNKS 2
47 
48 #include "yaffs_ecc.h"
49 
50 
51 /* Robustification (if it ever comes about...) */
52 static void yaffs_RetireBlock(yaffs_Device * dev, int blockInNAND);
53 static void yaffs_HandleWriteChunkError(yaffs_Device * dev, int chunkInNAND, int erasedOk);
54 static void yaffs_HandleWriteChunkOk(yaffs_Device * dev, int chunkInNAND,
55 				     const __u8 * data,
56 				     const yaffs_ExtendedTags * tags);
57 static void yaffs_HandleUpdateChunk(yaffs_Device * dev, int chunkInNAND,
58 				    const yaffs_ExtendedTags * tags);
59 
60 /* Other local prototypes */
61 static int yaffs_UnlinkObject( yaffs_Object *obj);
62 static int yaffs_ObjectHasCachedWriteData(yaffs_Object *obj);
63 
64 static void yaffs_HardlinkFixup(yaffs_Device *dev, yaffs_Object *hardList);
65 
66 static int yaffs_WriteNewChunkWithTagsToNAND(yaffs_Device * dev,
67 					     const __u8 * buffer,
68 					     yaffs_ExtendedTags * tags,
69 					     int useReserve);
70 static int yaffs_PutChunkIntoFile(yaffs_Object * in, int chunkInInode,
71 				  int chunkInNAND, int inScan);
72 
73 static yaffs_Object *yaffs_CreateNewObject(yaffs_Device * dev, int number,
74 					   yaffs_ObjectType type);
75 static void yaffs_AddObjectToDirectory(yaffs_Object * directory,
76 				       yaffs_Object * obj);
77 static int yaffs_UpdateObjectHeader(yaffs_Object * in, const YCHAR * name,
78 				    int force, int isShrink, int shadows);
79 static void yaffs_RemoveObjectFromDirectory(yaffs_Object * obj);
80 static int yaffs_CheckStructures(void);
81 static int yaffs_DoGenericObjectDeletion(yaffs_Object * in);
82 
83 static yaffs_BlockInfo *yaffs_GetBlockInfo(yaffs_Device * dev, int blockNo);
84 
85 static __u8 *yaffs_GetTempBuffer(yaffs_Device * dev, int lineNo);
86 static void yaffs_ReleaseTempBuffer(yaffs_Device * dev, __u8 * buffer,
87 				    int lineNo);
88 
89 static int yaffs_CheckChunkErased(struct yaffs_DeviceStruct *dev,
90 				  int chunkInNAND);
91 
92 static int yaffs_UnlinkWorker(yaffs_Object * obj);
93 static void yaffs_DestroyObject(yaffs_Object * obj);
94 
95 static int yaffs_TagsMatch(const yaffs_ExtendedTags * tags, int objectId,
96 			   int chunkInObject);
97 
98 loff_t yaffs_GetFileSize(yaffs_Object * obj);
99 
100 static int yaffs_AllocateChunk(yaffs_Device * dev, int useReserve, yaffs_BlockInfo **blockUsedPtr);
101 
102 static void yaffs_VerifyFreeChunks(yaffs_Device * dev);
103 
104 static void yaffs_CheckObjectDetailsLoaded(yaffs_Object *in);
105 
106 #ifdef YAFFS_PARANOID
107 static int yaffs_CheckFileSanity(yaffs_Object * in);
108 #else
109 #define yaffs_CheckFileSanity(in)
110 #endif
111 
112 static void yaffs_InvalidateWholeChunkCache(yaffs_Object * in);
113 static void yaffs_InvalidateChunkCache(yaffs_Object * object, int chunkId);
114 
115 static void yaffs_InvalidateCheckpoint(yaffs_Device *dev);
116 
117 static int yaffs_FindChunkInFile(yaffs_Object * in, int chunkInInode,
118 				 yaffs_ExtendedTags * tags);
119 
120 static __u32 yaffs_GetChunkGroupBase(yaffs_Device *dev, yaffs_Tnode *tn, unsigned pos);
121 static yaffs_Tnode *yaffs_FindLevel0Tnode(yaffs_Device * dev,
122 					  yaffs_FileStructure * fStruct,
123 					  __u32 chunkId);
124 
125 
126 /* Function to calculate chunk and offset */
127 
128 static void yaffs_AddrToChunk(yaffs_Device *dev, loff_t addr, __u32 *chunk, __u32 *offset)
129 {
130 	if(dev->chunkShift){
131 		/* Easy-peasy power of 2 case */
132 		*chunk  = (__u32)(addr >> dev->chunkShift);
133 		*offset = (__u32)(addr & dev->chunkMask);
134 	}
135 	else if(dev->crumbsPerChunk)
136 	{
137 		/* Case where we're using "crumbs" */
138 		*offset = (__u32)(addr & dev->crumbMask);
139 		addr >>= dev->crumbShift;
140 		*chunk = ((__u32)addr)/dev->crumbsPerChunk;
141 		*offset += ((addr - (*chunk * dev->crumbsPerChunk)) << dev->crumbShift);
142 	}
143 	else
144 		YBUG();
145 }
146 
147 /* Function to return the number of shifts for a power of 2 greater than or equal
148  * to the given number
149  * Note we don't try to cater for all possible numbers and this does not have to
150  * be hellishly efficient.
151  */
152 
153 static __u32 ShiftsGE(__u32 x)
154 {
155 	int extraBits;
156 	int nShifts;
157 
158 	nShifts = extraBits = 0;
159 
160 	while(x>1){
161 		if(x & 1) extraBits++;
162 		x>>=1;
163 		nShifts++;
164 	}
165 
166 	if(extraBits)
167 		nShifts++;
168 
169 	return nShifts;
170 }
171 
172 /* Function to return the number of shifts to get a 1 in bit 0
173  */
174 
175 static __u32 ShiftDiv(__u32 x)
176 {
177 	int nShifts;
178 
179 	nShifts =  0;
180 
181 	if(!x) return 0;
182 
183 	while( !(x&1)){
184 		x>>=1;
185 		nShifts++;
186 	}
187 
188 	return nShifts;
189 }
190 
191 
192 
193 /*
194  * Temporary buffer manipulations.
195  */
196 
197 static int yaffs_InitialiseTempBuffers(yaffs_Device *dev)
198 {
199 	int i;
200 	__u8 *buf = (__u8 *)1;
201 
202 	memset(dev->tempBuffer,0,sizeof(dev->tempBuffer));
203 
204 	for (i = 0; buf && i < YAFFS_N_TEMP_BUFFERS; i++) {
205 		dev->tempBuffer[i].line = 0;	/* not in use */
206 		dev->tempBuffer[i].buffer = buf =
207 		    YMALLOC_DMA(dev->nDataBytesPerChunk);
208 	}
209 
210 	return buf ? YAFFS_OK : YAFFS_FAIL;
211 
212 }
213 
214 static __u8 *yaffs_GetTempBuffer(yaffs_Device * dev, int lineNo)
215 {
216 	int i, j;
217 	for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
218 		if (dev->tempBuffer[i].line == 0) {
219 			dev->tempBuffer[i].line = lineNo;
220 			if ((i + 1) > dev->maxTemp) {
221 				dev->maxTemp = i + 1;
222 				for (j = 0; j <= i; j++)
223 					dev->tempBuffer[j].maxLine =
224 					    dev->tempBuffer[j].line;
225 			}
226 
227 			return dev->tempBuffer[i].buffer;
228 		}
229 	}
230 
231 	T(YAFFS_TRACE_BUFFERS,
232 	  (TSTR("Out of temp buffers at line %d, other held by lines:"),
233 	   lineNo));
234 	for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
235 		T(YAFFS_TRACE_BUFFERS, (TSTR(" %d "), dev->tempBuffer[i].line));
236 	}
237 	T(YAFFS_TRACE_BUFFERS, (TSTR(" " TENDSTR)));
238 
239 	/*
240 	 * If we got here then we have to allocate an unmanaged one
241 	 * This is not good.
242 	 */
243 
244 	dev->unmanagedTempAllocations++;
245 	return YMALLOC(dev->nDataBytesPerChunk);
246 
247 }
248 
249 static void yaffs_ReleaseTempBuffer(yaffs_Device * dev, __u8 * buffer,
250 				    int lineNo)
251 {
252 	int i;
253 	for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
254 		if (dev->tempBuffer[i].buffer == buffer) {
255 			dev->tempBuffer[i].line = 0;
256 			return;
257 		}
258 	}
259 
260 	if (buffer) {
261 		/* assume it is an unmanaged one. */
262 		T(YAFFS_TRACE_BUFFERS,
263 		  (TSTR("Releasing unmanaged temp buffer in line %d" TENDSTR),
264 		   lineNo));
265 		YFREE(buffer);
266 		dev->unmanagedTempDeallocations++;
267 	}
268 
269 }
270 
271 /*
272  * Determine if we have a managed buffer.
273  */
274 int yaffs_IsManagedTempBuffer(yaffs_Device * dev, const __u8 * buffer)
275 {
276 	int i;
277 	for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
278 		if (dev->tempBuffer[i].buffer == buffer)
279 			return 1;
280 
281 	}
282 
283     for (i = 0; i < dev->nShortOpCaches; i++) {
284 	if( dev->srCache[i].data == buffer )
285 	    return 1;
286 
287     }
288 
289     if (buffer == dev->checkpointBuffer)
290       return 1;
291 
292     T(YAFFS_TRACE_ALWAYS,
293 	  (TSTR("yaffs: unmaged buffer detected.\n" TENDSTR)));
294     return 0;
295 }
296 
297 
298 
299 /*
300  * Chunk bitmap manipulations
301  */
302 
303 static Y_INLINE __u8 *yaffs_BlockBits(yaffs_Device * dev, int blk)
304 {
305 	if (blk < dev->internalStartBlock || blk > dev->internalEndBlock) {
306 		T(YAFFS_TRACE_ERROR,
307 		  (TSTR("**>> yaffs: BlockBits block %d is not valid" TENDSTR),
308 		   blk));
309 		YBUG();
310 	}
311 	return dev->chunkBits +
312 	    (dev->chunkBitmapStride * (blk - dev->internalStartBlock));
313 }
314 
315 static Y_INLINE void yaffs_VerifyChunkBitId(yaffs_Device *dev, int blk, int chunk)
316 {
317 	if(blk < dev->internalStartBlock || blk > dev->internalEndBlock ||
318 	   chunk < 0 || chunk >= dev->nChunksPerBlock) {
319 	   T(YAFFS_TRACE_ERROR,
320 	    (TSTR("**>> yaffs: Chunk Id (%d:%d) invalid"TENDSTR),blk,chunk));
321 	    YBUG();
322 	}
323 }
324 
325 static Y_INLINE void yaffs_ClearChunkBits(yaffs_Device * dev, int blk)
326 {
327 	__u8 *blkBits = yaffs_BlockBits(dev, blk);
328 
329 	memset(blkBits, 0, dev->chunkBitmapStride);
330 }
331 
332 static Y_INLINE void yaffs_ClearChunkBit(yaffs_Device * dev, int blk, int chunk)
333 {
334 	__u8 *blkBits = yaffs_BlockBits(dev, blk);
335 
336 	yaffs_VerifyChunkBitId(dev,blk,chunk);
337 
338 	blkBits[chunk / 8] &= ~(1 << (chunk & 7));
339 }
340 
341 static Y_INLINE void yaffs_SetChunkBit(yaffs_Device * dev, int blk, int chunk)
342 {
343 	__u8 *blkBits = yaffs_BlockBits(dev, blk);
344 
345 	yaffs_VerifyChunkBitId(dev,blk,chunk);
346 
347 	blkBits[chunk / 8] |= (1 << (chunk & 7));
348 }
349 
350 static Y_INLINE int yaffs_CheckChunkBit(yaffs_Device * dev, int blk, int chunk)
351 {
352 	__u8 *blkBits = yaffs_BlockBits(dev, blk);
353 	yaffs_VerifyChunkBitId(dev,blk,chunk);
354 
355 	return (blkBits[chunk / 8] & (1 << (chunk & 7))) ? 1 : 0;
356 }
357 
358 static Y_INLINE int yaffs_StillSomeChunkBits(yaffs_Device * dev, int blk)
359 {
360 	__u8 *blkBits = yaffs_BlockBits(dev, blk);
361 	int i;
362 	for (i = 0; i < dev->chunkBitmapStride; i++) {
363 		if (*blkBits)
364 			return 1;
365 		blkBits++;
366 	}
367 	return 0;
368 }
369 
370 static int yaffs_CountChunkBits(yaffs_Device * dev, int blk)
371 {
372 	__u8 *blkBits = yaffs_BlockBits(dev, blk);
373 	int i;
374 	int n = 0;
375 	for (i = 0; i < dev->chunkBitmapStride; i++) {
376 		__u8 x = *blkBits;
377 		while(x){
378 			if(x & 1)
379 				n++;
380 			x >>=1;
381 		}
382 
383 		blkBits++;
384 	}
385 	return n;
386 }
387 
388 /*
389  * Verification code
390  */
391 
392 static Y_INLINE int yaffs_SkipVerification(yaffs_Device *dev)
393 {
394 	return !(yaffs_traceMask & (YAFFS_TRACE_VERIFY | YAFFS_TRACE_VERIFY_FULL));
395 }
396 
397 static Y_INLINE int yaffs_SkipFullVerification(yaffs_Device *dev)
398 {
399 	return !(yaffs_traceMask & (YAFFS_TRACE_VERIFY_FULL));
400 }
401 
402 static Y_INLINE int yaffs_SkipNANDVerification(yaffs_Device *dev)
403 {
404 	return !(yaffs_traceMask & (YAFFS_TRACE_VERIFY_NAND));
405 }
406 
407 static const char * blockStateName[] = {
408 "Unknown",
409 "Needs scanning",
410 "Scanning",
411 "Empty",
412 "Allocating",
413 "Full",
414 "Dirty",
415 "Checkpoint",
416 "Collecting",
417 "Dead"
418 };
419 
420 static void yaffs_VerifyBlock(yaffs_Device *dev,yaffs_BlockInfo *bi,int n)
421 {
422 	int actuallyUsed;
423 	int inUse;
424 
425 	if(yaffs_SkipVerification(dev))
426 		return;
427 
428 	/* Report illegal runtime states */
429 	if(bi->blockState <0 || bi->blockState >= YAFFS_NUMBER_OF_BLOCK_STATES)
430 		T(YAFFS_TRACE_VERIFY,(TSTR("Block %d has undefined state %d"TENDSTR),n,bi->blockState));
431 
432 	switch(bi->blockState){
433 	 case YAFFS_BLOCK_STATE_UNKNOWN:
434 	 case YAFFS_BLOCK_STATE_SCANNING:
435 	 case YAFFS_BLOCK_STATE_NEEDS_SCANNING:
436 		T(YAFFS_TRACE_VERIFY,(TSTR("Block %d has bad run-state %s"TENDSTR),
437 		n,blockStateName[bi->blockState]));
438 	}
439 
440 	/* Check pages in use and soft deletions are legal */
441 
442 	actuallyUsed = bi->pagesInUse - bi->softDeletions;
443 
444 	if(bi->pagesInUse < 0 || bi->pagesInUse > dev->nChunksPerBlock ||
445 	   bi->softDeletions < 0 || bi->softDeletions > dev->nChunksPerBlock ||
446 	   actuallyUsed < 0 || actuallyUsed > dev->nChunksPerBlock)
447 		T(YAFFS_TRACE_VERIFY,(TSTR("Block %d has illegal values pagesInUsed %d softDeletions %d"TENDSTR),
448 		n,bi->pagesInUse,bi->softDeletions));
449 
450 
451 	/* Check chunk bitmap legal */
452 	inUse = yaffs_CountChunkBits(dev,n);
453 	if(inUse != bi->pagesInUse)
454 		T(YAFFS_TRACE_VERIFY,(TSTR("Block %d has inconsistent values pagesInUse %d counted chunk bits %d"TENDSTR),
455 			n,bi->pagesInUse,inUse));
456 
457 	/* Check that the sequence number is valid.
458 	 * Ten million is legal, but is very unlikely
459 	 */
460 	if(dev->isYaffs2 &&
461 	   (bi->blockState == YAFFS_BLOCK_STATE_ALLOCATING || bi->blockState == YAFFS_BLOCK_STATE_FULL) &&
462 	   (bi->sequenceNumber < YAFFS_LOWEST_SEQUENCE_NUMBER || bi->sequenceNumber > 10000000 ))
463 		T(YAFFS_TRACE_VERIFY,(TSTR("Block %d has suspect sequence number of %d"TENDSTR),
464 		n,bi->sequenceNumber));
465 
466 }
467 
468 static void yaffs_VerifyCollectedBlock(yaffs_Device *dev,yaffs_BlockInfo *bi,int n)
469 {
470 	yaffs_VerifyBlock(dev,bi,n);
471 
472 	/* After collection the block should be in the erased state */
473 	/* TODO: This will need to change if we do partial gc */
474 
475 	if(bi->blockState != YAFFS_BLOCK_STATE_EMPTY){
476 		T(YAFFS_TRACE_ERROR,(TSTR("Block %d is in state %d after gc, should be erased"TENDSTR),
477 			n,bi->blockState));
478 	}
479 }
480 
481 static void yaffs_VerifyBlocks(yaffs_Device *dev)
482 {
483 	int i;
484 	int nBlocksPerState[YAFFS_NUMBER_OF_BLOCK_STATES];
485 	int nIllegalBlockStates = 0;
486 
487 
488 	if(yaffs_SkipVerification(dev))
489 		return;
490 
491 	memset(nBlocksPerState,0,sizeof(nBlocksPerState));
492 
493 
494 	for(i = dev->internalStartBlock; i <= dev->internalEndBlock; i++){
495 		yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev,i);
496 		yaffs_VerifyBlock(dev,bi,i);
497 
498 		if(bi->blockState >=0 && bi->blockState < YAFFS_NUMBER_OF_BLOCK_STATES)
499 			nBlocksPerState[bi->blockState]++;
500 		else
501 			nIllegalBlockStates++;
502 
503 	}
504 
505 	T(YAFFS_TRACE_VERIFY,(TSTR(""TENDSTR)));
506 	T(YAFFS_TRACE_VERIFY,(TSTR("Block summary"TENDSTR)));
507 
508 	T(YAFFS_TRACE_VERIFY,(TSTR("%d blocks have illegal states"TENDSTR),nIllegalBlockStates));
509 	if(nBlocksPerState[YAFFS_BLOCK_STATE_ALLOCATING] > 1)
510 		T(YAFFS_TRACE_VERIFY,(TSTR("Too many allocating blocks"TENDSTR)));
511 
512 	for(i = 0; i < YAFFS_NUMBER_OF_BLOCK_STATES; i++)
513 		T(YAFFS_TRACE_VERIFY,
514 		  (TSTR("%s %d blocks"TENDSTR),
515 		  blockStateName[i],nBlocksPerState[i]));
516 
517 	if(dev->blocksInCheckpoint != nBlocksPerState[YAFFS_BLOCK_STATE_CHECKPOINT])
518 		T(YAFFS_TRACE_VERIFY,
519 		 (TSTR("Checkpoint block count wrong dev %d count %d"TENDSTR),
520 		 dev->blocksInCheckpoint, nBlocksPerState[YAFFS_BLOCK_STATE_CHECKPOINT]));
521 
522 	if(dev->nErasedBlocks != nBlocksPerState[YAFFS_BLOCK_STATE_EMPTY])
523 		T(YAFFS_TRACE_VERIFY,
524 		 (TSTR("Erased block count wrong dev %d count %d"TENDSTR),
525 		 dev->nErasedBlocks, nBlocksPerState[YAFFS_BLOCK_STATE_EMPTY]));
526 
527 	if(nBlocksPerState[YAFFS_BLOCK_STATE_COLLECTING] > 1)
528 		T(YAFFS_TRACE_VERIFY,
529 		 (TSTR("Too many collecting blocks %d (max is 1)"TENDSTR),
530 		 nBlocksPerState[YAFFS_BLOCK_STATE_COLLECTING]));
531 
532 	T(YAFFS_TRACE_VERIFY,(TSTR(""TENDSTR)));
533 
534 }
535 
536 /*
537  * Verify the object header. oh must be valid, but obj and tags may be NULL in which
538  * case those tests will not be performed.
539  */
540 static void yaffs_VerifyObjectHeader(yaffs_Object *obj, yaffs_ObjectHeader *oh, yaffs_ExtendedTags *tags, int parentCheck)
541 {
542 	if(yaffs_SkipVerification(obj->myDev))
543 		return;
544 
545 	if(!(tags && obj && oh)){
546 		T(YAFFS_TRACE_VERIFY,
547 				(TSTR("Verifying object header tags %x obj %x oh %x"TENDSTR),
548 				(__u32)tags,(__u32)obj,(__u32)oh));
549 		return;
550 	}
551 
552 	if(oh->type <= YAFFS_OBJECT_TYPE_UNKNOWN ||
553 	   oh->type > YAFFS_OBJECT_TYPE_MAX)
554 		T(YAFFS_TRACE_VERIFY,
555 		 (TSTR("Obj %d header type is illegal value 0x%x"TENDSTR),
556 		 tags->objectId, oh->type));
557 
558 	if(tags->objectId != obj->objectId)
559 		T(YAFFS_TRACE_VERIFY,
560 		 (TSTR("Obj %d header mismatch objectId %d"TENDSTR),
561 		 tags->objectId, obj->objectId));
562 
563 
564 	/*
565 	 * Check that the object's parent ids match if parentCheck requested.
566 	 *
567 	 * Tests do not apply to the root object.
568 	 */
569 
570 	if(parentCheck && tags->objectId > 1 && !obj->parent)
571 		T(YAFFS_TRACE_VERIFY,
572 		 (TSTR("Obj %d header mismatch parentId %d obj->parent is NULL"TENDSTR),
573 		 tags->objectId, oh->parentObjectId));
574 
575 
576 	if(parentCheck && obj->parent &&
577 	   oh->parentObjectId != obj->parent->objectId &&
578 	   (oh->parentObjectId != YAFFS_OBJECTID_UNLINKED ||
579 	    obj->parent->objectId != YAFFS_OBJECTID_DELETED))
580 		T(YAFFS_TRACE_VERIFY,
581 		 (TSTR("Obj %d header mismatch parentId %d parentObjectId %d"TENDSTR),
582 		 tags->objectId, oh->parentObjectId, obj->parent->objectId));
583 
584 
585 	if(tags->objectId > 1 && oh->name[0] == 0) /* Null name */
586 		T(YAFFS_TRACE_VERIFY,
587 		(TSTR("Obj %d header name is NULL"TENDSTR),
588 		 obj->objectId));
589 
590 	if(tags->objectId > 1 && ((__u8)(oh->name[0])) == 0xff) /* Trashed name */
591 		T(YAFFS_TRACE_VERIFY,
592 		(TSTR("Obj %d header name is 0xFF"TENDSTR),
593 		 obj->objectId));
594 }
595 
596 static void yaffs_VerifyFile(yaffs_Object *obj)
597 {
598 	int requiredTallness;
599 	int actualTallness;
600 	__u32 lastChunk;
601 	__u32 x;
602 	__u32 i;
603 	yaffs_Device *dev;
604 	yaffs_ExtendedTags tags;
605 	yaffs_Tnode *tn;
606 	__u32 objectId;
607 
608 	if(obj && yaffs_SkipVerification(obj->myDev))
609 		return;
610 
611 	dev = obj->myDev;
612 	objectId = obj->objectId;
613 
614 	/* Check file size is consistent with tnode depth */
615 	lastChunk =  obj->variant.fileVariant.fileSize / dev->nDataBytesPerChunk + 1;
616 	x = lastChunk >> YAFFS_TNODES_LEVEL0_BITS;
617 	requiredTallness = 0;
618 	while (x> 0) {
619 		x >>= YAFFS_TNODES_INTERNAL_BITS;
620 		requiredTallness++;
621 	}
622 
623 	actualTallness = obj->variant.fileVariant.topLevel;
624 
625 	if(requiredTallness > actualTallness )
626 		T(YAFFS_TRACE_VERIFY,
627 		(TSTR("Obj %d had tnode tallness %d, needs to be %d"TENDSTR),
628 		 obj->objectId,actualTallness, requiredTallness));
629 
630 
631 	/* Check that the chunks in the tnode tree are all correct.
632 	 * We do this by scanning through the tnode tree and
633 	 * checking the tags for every chunk match.
634 	 */
635 
636 	if(yaffs_SkipNANDVerification(dev))
637 		return;
638 
639 	for(i = 1; i <= lastChunk; i++){
640 		tn = yaffs_FindLevel0Tnode(dev, &obj->variant.fileVariant,i);
641 
642 		if (tn) {
643 			__u32 theChunk = yaffs_GetChunkGroupBase(dev,tn,i);
644 			if(theChunk > 0){
645 				/* T(~0,(TSTR("verifying (%d:%d) %d"TENDSTR),objectId,i,theChunk)); */
646 				yaffs_ReadChunkWithTagsFromNAND(dev,theChunk,NULL, &tags);
647 				if(tags.objectId != objectId || tags.chunkId != i){
648 					T(~0,(TSTR("Object %d chunkId %d NAND mismatch chunk %d tags (%d:%d)"TENDSTR),
649 						objectId, i, theChunk,
650 						tags.objectId, tags.chunkId));
651 				}
652 			}
653 		}
654 
655 	}
656 
657 }
658 
659 static void yaffs_VerifyDirectory(yaffs_Object *obj)
660 {
661 	if(obj && yaffs_SkipVerification(obj->myDev))
662 		return;
663 
664 }
665 
666 static void yaffs_VerifyHardLink(yaffs_Object *obj)
667 {
668 	if(obj && yaffs_SkipVerification(obj->myDev))
669 		return;
670 
671 	/* Verify sane equivalent object */
672 }
673 
674 static void yaffs_VerifySymlink(yaffs_Object *obj)
675 {
676 	if(obj && yaffs_SkipVerification(obj->myDev))
677 		return;
678 
679 	/* Verify symlink string */
680 }
681 
682 static void yaffs_VerifySpecial(yaffs_Object *obj)
683 {
684 	if(obj && yaffs_SkipVerification(obj->myDev))
685 		return;
686 }
687 
688 static void yaffs_VerifyObject(yaffs_Object *obj)
689 {
690 	yaffs_Device *dev;
691 
692 	__u32 chunkMin;
693 	__u32 chunkMax;
694 
695 	__u32 chunkIdOk;
696 	__u32 chunkIsLive;
697 
698 	if(!obj)
699 		return;
700 
701 	dev = obj->myDev;
702 
703 	if(yaffs_SkipVerification(dev))
704 		return;
705 
706 	/* Check sane object header chunk */
707 
708 	chunkMin = dev->internalStartBlock * dev->nChunksPerBlock;
709 	chunkMax = (dev->internalEndBlock+1) * dev->nChunksPerBlock - 1;
710 
711 	chunkIdOk = (obj->chunkId >= chunkMin && obj->chunkId <= chunkMax);
712 	chunkIsLive = chunkIdOk &&
713 			yaffs_CheckChunkBit(dev,
714 					    obj->chunkId / dev->nChunksPerBlock,
715 					    obj->chunkId % dev->nChunksPerBlock);
716 	if(!obj->fake &&
717 	    (!chunkIdOk || !chunkIsLive)) {
718 	   T(YAFFS_TRACE_VERIFY,
719 	   (TSTR("Obj %d has chunkId %d %s %s"TENDSTR),
720 	   obj->objectId,obj->chunkId,
721 	   chunkIdOk ? "" : ",out of range",
722 	   chunkIsLive || !chunkIdOk ? "" : ",marked as deleted"));
723 	}
724 
725 	if(chunkIdOk && chunkIsLive &&!yaffs_SkipNANDVerification(dev)) {
726 		yaffs_ExtendedTags tags;
727 		yaffs_ObjectHeader *oh;
728 		__u8 *buffer = yaffs_GetTempBuffer(dev,__LINE__);
729 
730 		oh = (yaffs_ObjectHeader *)buffer;
731 
732 		yaffs_ReadChunkWithTagsFromNAND(dev, obj->chunkId,buffer, &tags);
733 
734 		yaffs_VerifyObjectHeader(obj,oh,&tags,1);
735 
736 		yaffs_ReleaseTempBuffer(dev,buffer,__LINE__);
737 	}
738 
739 	/* Verify it has a parent */
740 	if(obj && !obj->fake &&
741 	   (!obj->parent || obj->parent->myDev != dev)){
742 	   T(YAFFS_TRACE_VERIFY,
743 	   (TSTR("Obj %d has parent pointer %p which does not look like an object"TENDSTR),
744 	   obj->objectId,obj->parent));
745 	}
746 
747 	/* Verify parent is a directory */
748 	if(obj->parent && obj->parent->variantType != YAFFS_OBJECT_TYPE_DIRECTORY){
749 	   T(YAFFS_TRACE_VERIFY,
750 	   (TSTR("Obj %d's parent is not a directory (type %d)"TENDSTR),
751 	   obj->objectId,obj->parent->variantType));
752 	}
753 
754 	switch(obj->variantType){
755 	case YAFFS_OBJECT_TYPE_FILE:
756 		yaffs_VerifyFile(obj);
757 		break;
758 	case YAFFS_OBJECT_TYPE_SYMLINK:
759 		yaffs_VerifySymlink(obj);
760 		break;
761 	case YAFFS_OBJECT_TYPE_DIRECTORY:
762 		yaffs_VerifyDirectory(obj);
763 		break;
764 	case YAFFS_OBJECT_TYPE_HARDLINK:
765 		yaffs_VerifyHardLink(obj);
766 		break;
767 	case YAFFS_OBJECT_TYPE_SPECIAL:
768 		yaffs_VerifySpecial(obj);
769 		break;
770 	case YAFFS_OBJECT_TYPE_UNKNOWN:
771 	default:
772 		T(YAFFS_TRACE_VERIFY,
773 		(TSTR("Obj %d has illegaltype %d"TENDSTR),
774 		obj->objectId,obj->variantType));
775 		break;
776 	}
777 
778 
779 }
780 
781 static void yaffs_VerifyObjects(yaffs_Device *dev)
782 {
783 	yaffs_Object *obj;
784 	int i;
785 	struct list_head *lh;
786 
787 	if(yaffs_SkipVerification(dev))
788 		return;
789 
790 	/* Iterate through the objects in each hash entry */
791 
792 	 for(i = 0; i <  YAFFS_NOBJECT_BUCKETS; i++){
793 		list_for_each(lh, &dev->objectBucket[i].list) {
794 			if (lh) {
795 				obj = list_entry(lh, yaffs_Object, hashLink);
796 				yaffs_VerifyObject(obj);
797 			}
798 		}
799 	 }
800 
801 }
802 
803 
804 /*
805  *  Simple hash function. Needs to have a reasonable spread
806  */
807 
808 static Y_INLINE int yaffs_HashFunction(int n)
809 {
810 /* XXX U-BOOT XXX */
811 	/*n = abs(n); */
812 	if (n < 0)
813 		n = -n;
814 	return (n % YAFFS_NOBJECT_BUCKETS);
815 }
816 
817 /*
818  * Access functions to useful fake objects
819  */
820 
821 yaffs_Object *yaffs_Root(yaffs_Device * dev)
822 {
823 	return dev->rootDir;
824 }
825 
826 yaffs_Object *yaffs_LostNFound(yaffs_Device * dev)
827 {
828 	return dev->lostNFoundDir;
829 }
830 
831 
832 /*
833  *  Erased NAND checking functions
834  */
835 
836 int yaffs_CheckFF(__u8 * buffer, int nBytes)
837 {
838 	/* Horrible, slow implementation */
839 	while (nBytes--) {
840 		if (*buffer != 0xFF)
841 			return 0;
842 		buffer++;
843 	}
844 	return 1;
845 }
846 
847 static int yaffs_CheckChunkErased(struct yaffs_DeviceStruct *dev,
848 				  int chunkInNAND)
849 {
850 
851 	int retval = YAFFS_OK;
852 	__u8 *data = yaffs_GetTempBuffer(dev, __LINE__);
853 	yaffs_ExtendedTags tags;
854 
855 	yaffs_ReadChunkWithTagsFromNAND(dev, chunkInNAND, data, &tags);
856 
857 	if(tags.eccResult > YAFFS_ECC_RESULT_NO_ERROR)
858 		retval = YAFFS_FAIL;
859 
860 
861 	if (!yaffs_CheckFF(data, dev->nDataBytesPerChunk) || tags.chunkUsed) {
862 		T(YAFFS_TRACE_NANDACCESS,
863 		  (TSTR("Chunk %d not erased" TENDSTR), chunkInNAND));
864 		retval = YAFFS_FAIL;
865 	}
866 
867 	yaffs_ReleaseTempBuffer(dev, data, __LINE__);
868 
869 	return retval;
870 
871 }
872 
873 static int yaffs_WriteNewChunkWithTagsToNAND(struct yaffs_DeviceStruct *dev,
874 					     const __u8 * data,
875 					     yaffs_ExtendedTags * tags,
876 					     int useReserve)
877 {
878 	int attempts = 0;
879 	int writeOk = 0;
880 	int chunk;
881 
882 	yaffs_InvalidateCheckpoint(dev);
883 
884 	do {
885 		yaffs_BlockInfo *bi = 0;
886 		int erasedOk = 0;
887 
888 		chunk = yaffs_AllocateChunk(dev, useReserve, &bi);
889 		if (chunk < 0) {
890 			/* no space */
891 			break;
892 		}
893 
894 		/* First check this chunk is erased, if it needs
895 		 * checking.  The checking policy (unless forced
896 		 * always on) is as follows:
897 		 *
898 		 * Check the first page we try to write in a block.
899 		 * If the check passes then we don't need to check any
900 		 * more.	If the check fails, we check again...
901 		 * If the block has been erased, we don't need to check.
902 		 *
903 		 * However, if the block has been prioritised for gc,
904 		 * then we think there might be something odd about
905 		 * this block and stop using it.
906 		 *
907 		 * Rationale: We should only ever see chunks that have
908 		 * not been erased if there was a partially written
909 		 * chunk due to power loss.  This checking policy should
910 		 * catch that case with very few checks and thus save a
911 		 * lot of checks that are most likely not needed.
912 		 */
913 		if (bi->gcPrioritise) {
914 			yaffs_DeleteChunk(dev, chunk, 1, __LINE__);
915 			/* try another chunk */
916 			continue;
917 		}
918 
919 		/* let's give it a try */
920 		attempts++;
921 
922 #ifdef CONFIG_YAFFS_ALWAYS_CHECK_CHUNK_ERASED
923 		bi->skipErasedCheck = 0;
924 #endif
925 		if (!bi->skipErasedCheck) {
926 			erasedOk = yaffs_CheckChunkErased(dev, chunk);
927 			if (erasedOk != YAFFS_OK) {
928 				T(YAFFS_TRACE_ERROR,
929 				(TSTR ("**>> yaffs chunk %d was not erased"
930 				TENDSTR), chunk));
931 
932 				/* try another chunk */
933 				continue;
934 			}
935 			bi->skipErasedCheck = 1;
936 		}
937 
938 		writeOk = yaffs_WriteChunkWithTagsToNAND(dev, chunk,
939 				data, tags);
940 		if (writeOk != YAFFS_OK) {
941 			yaffs_HandleWriteChunkError(dev, chunk, erasedOk);
942 			/* try another chunk */
943 			continue;
944 		}
945 
946 		/* Copy the data into the robustification buffer */
947 		yaffs_HandleWriteChunkOk(dev, chunk, data, tags);
948 
949 	} while (writeOk != YAFFS_OK &&
950 		(yaffs_wr_attempts <= 0 || attempts <= yaffs_wr_attempts));
951 
952 	if(!writeOk)
953 		chunk = -1;
954 
955 	if (attempts > 1) {
956 		T(YAFFS_TRACE_ERROR,
957 			(TSTR("**>> yaffs write required %d attempts" TENDSTR),
958 			attempts));
959 
960 		dev->nRetriedWrites += (attempts - 1);
961 	}
962 
963 	return chunk;
964 }
965 
966 /*
967  * Block retiring for handling a broken block.
968  */
969 
970 static void yaffs_RetireBlock(yaffs_Device * dev, int blockInNAND)
971 {
972 	yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, blockInNAND);
973 
974 	yaffs_InvalidateCheckpoint(dev);
975 
976 	yaffs_MarkBlockBad(dev, blockInNAND);
977 
978 	bi->blockState = YAFFS_BLOCK_STATE_DEAD;
979 	bi->gcPrioritise = 0;
980 	bi->needsRetiring = 0;
981 
982 	dev->nRetiredBlocks++;
983 }
984 
985 /*
986  * Functions for robustisizing TODO
987  *
988  */
989 
990 static void yaffs_HandleWriteChunkOk(yaffs_Device * dev, int chunkInNAND,
991 				     const __u8 * data,
992 				     const yaffs_ExtendedTags * tags)
993 {
994 }
995 
996 static void yaffs_HandleUpdateChunk(yaffs_Device * dev, int chunkInNAND,
997 				    const yaffs_ExtendedTags * tags)
998 {
999 }
1000 
1001 void yaffs_HandleChunkError(yaffs_Device *dev, yaffs_BlockInfo *bi)
1002 {
1003 	if(!bi->gcPrioritise){
1004 		bi->gcPrioritise = 1;
1005 		dev->hasPendingPrioritisedGCs = 1;
1006 		bi->chunkErrorStrikes ++;
1007 
1008 		if(bi->chunkErrorStrikes > 3){
1009 			bi->needsRetiring = 1; /* Too many stikes, so retire this */
1010 			T(YAFFS_TRACE_ALWAYS, (TSTR("yaffs: Block struck out" TENDSTR)));
1011 
1012 		}
1013 
1014 	}
1015 }
1016 
1017 static void yaffs_HandleWriteChunkError(yaffs_Device * dev, int chunkInNAND, int erasedOk)
1018 {
1019 
1020 	int blockInNAND = chunkInNAND / dev->nChunksPerBlock;
1021 	yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, blockInNAND);
1022 
1023 	yaffs_HandleChunkError(dev,bi);
1024 
1025 
1026 	if(erasedOk ) {
1027 		/* Was an actual write failure, so mark the block for retirement  */
1028 		bi->needsRetiring = 1;
1029 		T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
1030 		  (TSTR("**>> Block %d needs retiring" TENDSTR), blockInNAND));
1031 
1032 
1033 	}
1034 
1035 	/* Delete the chunk */
1036 	yaffs_DeleteChunk(dev, chunkInNAND, 1, __LINE__);
1037 }
1038 
1039 
1040 /*---------------- Name handling functions ------------*/
1041 
1042 static __u16 yaffs_CalcNameSum(const YCHAR * name)
1043 {
1044 	__u16 sum = 0;
1045 	__u16 i = 1;
1046 
1047 	YUCHAR *bname = (YUCHAR *) name;
1048 	if (bname) {
1049 		while ((*bname) && (i < (YAFFS_MAX_NAME_LENGTH/2))) {
1050 
1051 #ifdef CONFIG_YAFFS_CASE_INSENSITIVE
1052 			sum += yaffs_toupper(*bname) * i;
1053 #else
1054 			sum += (*bname) * i;
1055 #endif
1056 			i++;
1057 			bname++;
1058 		}
1059 	}
1060 	return sum;
1061 }
1062 
1063 static void yaffs_SetObjectName(yaffs_Object * obj, const YCHAR * name)
1064 {
1065 #ifdef CONFIG_YAFFS_SHORT_NAMES_IN_RAM
1066 	if (name && yaffs_strlen(name) <= YAFFS_SHORT_NAME_LENGTH) {
1067 		yaffs_strcpy(obj->shortName, name);
1068 	} else {
1069 		obj->shortName[0] = _Y('\0');
1070 	}
1071 #endif
1072 	obj->sum = yaffs_CalcNameSum(name);
1073 }
1074 
1075 /*-------------------- TNODES -------------------
1076 
1077  * List of spare tnodes
1078  * The list is hooked together using the first pointer
1079  * in the tnode.
1080  */
1081 
1082 /* yaffs_CreateTnodes creates a bunch more tnodes and
1083  * adds them to the tnode free list.
1084  * Don't use this function directly
1085  */
1086 
1087 static int yaffs_CreateTnodes(yaffs_Device * dev, int nTnodes)
1088 {
1089 	int i;
1090 	int tnodeSize;
1091 	yaffs_Tnode *newTnodes;
1092 	__u8 *mem;
1093 	yaffs_Tnode *curr;
1094 	yaffs_Tnode *next;
1095 	yaffs_TnodeList *tnl;
1096 
1097 	if (nTnodes < 1)
1098 		return YAFFS_OK;
1099 
1100 	/* Calculate the tnode size in bytes for variable width tnode support.
1101 	 * Must be a multiple of 32-bits  */
1102 	tnodeSize = (dev->tnodeWidth * YAFFS_NTNODES_LEVEL0)/8;
1103 
1104 	/* make these things */
1105 
1106 	newTnodes = YMALLOC(nTnodes * tnodeSize);
1107 	mem = (__u8 *)newTnodes;
1108 
1109 	if (!newTnodes) {
1110 		T(YAFFS_TRACE_ERROR,
1111 		  (TSTR("yaffs: Could not allocate Tnodes" TENDSTR)));
1112 		return YAFFS_FAIL;
1113 	}
1114 
1115 	/* Hook them into the free list */
1116 #if 0
1117 	for (i = 0; i < nTnodes - 1; i++) {
1118 		newTnodes[i].internal[0] = &newTnodes[i + 1];
1119 #ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
1120 		newTnodes[i].internal[YAFFS_NTNODES_INTERNAL] = (void *)1;
1121 #endif
1122 	}
1123 
1124 	newTnodes[nTnodes - 1].internal[0] = dev->freeTnodes;
1125 #ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
1126 	newTnodes[nTnodes - 1].internal[YAFFS_NTNODES_INTERNAL] = (void *)1;
1127 #endif
1128 	dev->freeTnodes = newTnodes;
1129 #else
1130 	/* New hookup for wide tnodes */
1131 	for(i = 0; i < nTnodes -1; i++) {
1132 		curr = (yaffs_Tnode *) &mem[i * tnodeSize];
1133 		next = (yaffs_Tnode *) &mem[(i+1) * tnodeSize];
1134 		curr->internal[0] = next;
1135 	}
1136 
1137 	curr = (yaffs_Tnode *) &mem[(nTnodes - 1) * tnodeSize];
1138 	curr->internal[0] = dev->freeTnodes;
1139 	dev->freeTnodes = (yaffs_Tnode *)mem;
1140 
1141 #endif
1142 
1143 
1144 	dev->nFreeTnodes += nTnodes;
1145 	dev->nTnodesCreated += nTnodes;
1146 
1147 	/* Now add this bunch of tnodes to a list for freeing up.
1148 	 * NB If we can't add this to the management list it isn't fatal
1149 	 * but it just means we can't free this bunch of tnodes later.
1150 	 */
1151 
1152 	tnl = YMALLOC(sizeof(yaffs_TnodeList));
1153 	if (!tnl) {
1154 		T(YAFFS_TRACE_ERROR,
1155 		  (TSTR
1156 		   ("yaffs: Could not add tnodes to management list" TENDSTR)));
1157 		   return YAFFS_FAIL;
1158 
1159 	} else {
1160 		tnl->tnodes = newTnodes;
1161 		tnl->next = dev->allocatedTnodeList;
1162 		dev->allocatedTnodeList = tnl;
1163 	}
1164 
1165 	T(YAFFS_TRACE_ALLOCATE, (TSTR("yaffs: Tnodes added" TENDSTR)));
1166 
1167 	return YAFFS_OK;
1168 }
1169 
1170 /* GetTnode gets us a clean tnode. Tries to make allocate more if we run out */
1171 
1172 static yaffs_Tnode *yaffs_GetTnodeRaw(yaffs_Device * dev)
1173 {
1174 	yaffs_Tnode *tn = NULL;
1175 
1176 	/* If there are none left make more */
1177 	if (!dev->freeTnodes) {
1178 		yaffs_CreateTnodes(dev, YAFFS_ALLOCATION_NTNODES);
1179 	}
1180 
1181 	if (dev->freeTnodes) {
1182 		tn = dev->freeTnodes;
1183 #ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
1184 		if (tn->internal[YAFFS_NTNODES_INTERNAL] != (void *)1) {
1185 			/* Hoosterman, this thing looks like it isn't in the list */
1186 			T(YAFFS_TRACE_ALWAYS,
1187 			  (TSTR("yaffs: Tnode list bug 1" TENDSTR)));
1188 		}
1189 #endif
1190 		dev->freeTnodes = dev->freeTnodes->internal[0];
1191 		dev->nFreeTnodes--;
1192 	}
1193 
1194 	return tn;
1195 }
1196 
1197 static yaffs_Tnode *yaffs_GetTnode(yaffs_Device * dev)
1198 {
1199 	yaffs_Tnode *tn = yaffs_GetTnodeRaw(dev);
1200 
1201 	if(tn)
1202 		memset(tn, 0, (dev->tnodeWidth * YAFFS_NTNODES_LEVEL0)/8);
1203 
1204 	return tn;
1205 }
1206 
1207 /* FreeTnode frees up a tnode and puts it back on the free list */
1208 static void yaffs_FreeTnode(yaffs_Device * dev, yaffs_Tnode * tn)
1209 {
1210 	if (tn) {
1211 #ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
1212 		if (tn->internal[YAFFS_NTNODES_INTERNAL] != 0) {
1213 			/* Hoosterman, this thing looks like it is already in the list */
1214 			T(YAFFS_TRACE_ALWAYS,
1215 			  (TSTR("yaffs: Tnode list bug 2" TENDSTR)));
1216 		}
1217 		tn->internal[YAFFS_NTNODES_INTERNAL] = (void *)1;
1218 #endif
1219 		tn->internal[0] = dev->freeTnodes;
1220 		dev->freeTnodes = tn;
1221 		dev->nFreeTnodes++;
1222 	}
1223 }
1224 
1225 static void yaffs_DeinitialiseTnodes(yaffs_Device * dev)
1226 {
1227 	/* Free the list of allocated tnodes */
1228 	yaffs_TnodeList *tmp;
1229 
1230 	while (dev->allocatedTnodeList) {
1231 		tmp = dev->allocatedTnodeList->next;
1232 
1233 		YFREE(dev->allocatedTnodeList->tnodes);
1234 		YFREE(dev->allocatedTnodeList);
1235 		dev->allocatedTnodeList = tmp;
1236 
1237 	}
1238 
1239 	dev->freeTnodes = NULL;
1240 	dev->nFreeTnodes = 0;
1241 }
1242 
1243 static void yaffs_InitialiseTnodes(yaffs_Device * dev)
1244 {
1245 	dev->allocatedTnodeList = NULL;
1246 	dev->freeTnodes = NULL;
1247 	dev->nFreeTnodes = 0;
1248 	dev->nTnodesCreated = 0;
1249 
1250 }
1251 
1252 
1253 void yaffs_PutLevel0Tnode(yaffs_Device *dev, yaffs_Tnode *tn, unsigned pos, unsigned val)
1254 {
1255   __u32 *map = (__u32 *)tn;
1256   __u32 bitInMap;
1257   __u32 bitInWord;
1258   __u32 wordInMap;
1259   __u32 mask;
1260 
1261   pos &= YAFFS_TNODES_LEVEL0_MASK;
1262   val >>= dev->chunkGroupBits;
1263 
1264   bitInMap = pos * dev->tnodeWidth;
1265   wordInMap = bitInMap /32;
1266   bitInWord = bitInMap & (32 -1);
1267 
1268   mask = dev->tnodeMask << bitInWord;
1269 
1270   map[wordInMap] &= ~mask;
1271   map[wordInMap] |= (mask & (val << bitInWord));
1272 
1273   if(dev->tnodeWidth > (32-bitInWord)) {
1274     bitInWord = (32 - bitInWord);
1275     wordInMap++;;
1276     mask = dev->tnodeMask >> (/*dev->tnodeWidth -*/ bitInWord);
1277     map[wordInMap] &= ~mask;
1278     map[wordInMap] |= (mask & (val >> bitInWord));
1279   }
1280 }
1281 
1282 static __u32 yaffs_GetChunkGroupBase(yaffs_Device *dev, yaffs_Tnode *tn, unsigned pos)
1283 {
1284   __u32 *map = (__u32 *)tn;
1285   __u32 bitInMap;
1286   __u32 bitInWord;
1287   __u32 wordInMap;
1288   __u32 val;
1289 
1290   pos &= YAFFS_TNODES_LEVEL0_MASK;
1291 
1292   bitInMap = pos * dev->tnodeWidth;
1293   wordInMap = bitInMap /32;
1294   bitInWord = bitInMap & (32 -1);
1295 
1296   val = map[wordInMap] >> bitInWord;
1297 
1298   if(dev->tnodeWidth > (32-bitInWord)) {
1299     bitInWord = (32 - bitInWord);
1300     wordInMap++;;
1301     val |= (map[wordInMap] << bitInWord);
1302   }
1303 
1304   val &= dev->tnodeMask;
1305   val <<= dev->chunkGroupBits;
1306 
1307   return val;
1308 }
1309 
1310 /* ------------------- End of individual tnode manipulation -----------------*/
1311 
1312 /* ---------Functions to manipulate the look-up tree (made up of tnodes) ------
1313  * The look up tree is represented by the top tnode and the number of topLevel
1314  * in the tree. 0 means only the level 0 tnode is in the tree.
1315  */
1316 
1317 /* FindLevel0Tnode finds the level 0 tnode, if one exists. */
1318 static yaffs_Tnode *yaffs_FindLevel0Tnode(yaffs_Device * dev,
1319 					  yaffs_FileStructure * fStruct,
1320 					  __u32 chunkId)
1321 {
1322 
1323 	yaffs_Tnode *tn = fStruct->top;
1324 	__u32 i;
1325 	int requiredTallness;
1326 	int level = fStruct->topLevel;
1327 
1328 	/* Check sane level and chunk Id */
1329 	if (level < 0 || level > YAFFS_TNODES_MAX_LEVEL) {
1330 		return NULL;
1331 	}
1332 
1333 	if (chunkId > YAFFS_MAX_CHUNK_ID) {
1334 		return NULL;
1335 	}
1336 
1337 	/* First check we're tall enough (ie enough topLevel) */
1338 
1339 	i = chunkId >> YAFFS_TNODES_LEVEL0_BITS;
1340 	requiredTallness = 0;
1341 	while (i) {
1342 		i >>= YAFFS_TNODES_INTERNAL_BITS;
1343 		requiredTallness++;
1344 	}
1345 
1346 	if (requiredTallness > fStruct->topLevel) {
1347 		/* Not tall enough, so we can't find it, return NULL. */
1348 		return NULL;
1349 	}
1350 
1351 	/* Traverse down to level 0 */
1352 	while (level > 0 && tn) {
1353 		tn = tn->
1354 		    internal[(chunkId >>
1355 			       ( YAFFS_TNODES_LEVEL0_BITS +
1356 				 (level - 1) *
1357 				 YAFFS_TNODES_INTERNAL_BITS)
1358 			      ) &
1359 			     YAFFS_TNODES_INTERNAL_MASK];
1360 		level--;
1361 
1362 	}
1363 
1364 	return tn;
1365 }
1366 
1367 /* AddOrFindLevel0Tnode finds the level 0 tnode if it exists, otherwise first expands the tree.
1368  * This happens in two steps:
1369  *  1. If the tree isn't tall enough, then make it taller.
1370  *  2. Scan down the tree towards the level 0 tnode adding tnodes if required.
1371  *
1372  * Used when modifying the tree.
1373  *
1374  *  If the tn argument is NULL, then a fresh tnode will be added otherwise the specified tn will
1375  *  be plugged into the ttree.
1376  */
1377 
1378 static yaffs_Tnode *yaffs_AddOrFindLevel0Tnode(yaffs_Device * dev,
1379 					       yaffs_FileStructure * fStruct,
1380 					       __u32 chunkId,
1381 					       yaffs_Tnode *passedTn)
1382 {
1383 
1384 	int requiredTallness;
1385 	int i;
1386 	int l;
1387 	yaffs_Tnode *tn;
1388 
1389 	__u32 x;
1390 
1391 
1392 	/* Check sane level and page Id */
1393 	if (fStruct->topLevel < 0 || fStruct->topLevel > YAFFS_TNODES_MAX_LEVEL) {
1394 		return NULL;
1395 	}
1396 
1397 	if (chunkId > YAFFS_MAX_CHUNK_ID) {
1398 		return NULL;
1399 	}
1400 
1401 	/* First check we're tall enough (ie enough topLevel) */
1402 
1403 	x = chunkId >> YAFFS_TNODES_LEVEL0_BITS;
1404 	requiredTallness = 0;
1405 	while (x) {
1406 		x >>= YAFFS_TNODES_INTERNAL_BITS;
1407 		requiredTallness++;
1408 	}
1409 
1410 
1411 	if (requiredTallness > fStruct->topLevel) {
1412 		/* Not tall enough,gotta make the tree taller */
1413 		for (i = fStruct->topLevel; i < requiredTallness; i++) {
1414 
1415 			tn = yaffs_GetTnode(dev);
1416 
1417 			if (tn) {
1418 				tn->internal[0] = fStruct->top;
1419 				fStruct->top = tn;
1420 			} else {
1421 				T(YAFFS_TRACE_ERROR,
1422 				  (TSTR("yaffs: no more tnodes" TENDSTR)));
1423 			}
1424 		}
1425 
1426 		fStruct->topLevel = requiredTallness;
1427 	}
1428 
1429 	/* Traverse down to level 0, adding anything we need */
1430 
1431 	l = fStruct->topLevel;
1432 	tn = fStruct->top;
1433 
1434 	if(l > 0) {
1435 		while (l > 0 && tn) {
1436 			x = (chunkId >>
1437 			     ( YAFFS_TNODES_LEVEL0_BITS +
1438 			      (l - 1) * YAFFS_TNODES_INTERNAL_BITS)) &
1439 			    YAFFS_TNODES_INTERNAL_MASK;
1440 
1441 
1442 			if((l>1) && !tn->internal[x]){
1443 				/* Add missing non-level-zero tnode */
1444 				tn->internal[x] = yaffs_GetTnode(dev);
1445 
1446 			} else if(l == 1) {
1447 				/* Looking from level 1 at level 0 */
1448 				if (passedTn) {
1449 					/* If we already have one, then release it.*/
1450 					if(tn->internal[x])
1451 						yaffs_FreeTnode(dev,tn->internal[x]);
1452 					tn->internal[x] = passedTn;
1453 
1454 				} else if(!tn->internal[x]) {
1455 					/* Don't have one, none passed in */
1456 					tn->internal[x] = yaffs_GetTnode(dev);
1457 				}
1458 			}
1459 
1460 			tn = tn->internal[x];
1461 			l--;
1462 		}
1463 	} else {
1464 		/* top is level 0 */
1465 		if(passedTn) {
1466 			memcpy(tn,passedTn,(dev->tnodeWidth * YAFFS_NTNODES_LEVEL0)/8);
1467 			yaffs_FreeTnode(dev,passedTn);
1468 		}
1469 	}
1470 
1471 	return tn;
1472 }
1473 
1474 static int yaffs_FindChunkInGroup(yaffs_Device * dev, int theChunk,
1475 				  yaffs_ExtendedTags * tags, int objectId,
1476 				  int chunkInInode)
1477 {
1478 	int j;
1479 
1480 	for (j = 0; theChunk && j < dev->chunkGroupSize; j++) {
1481 		if (yaffs_CheckChunkBit
1482 		    (dev, theChunk / dev->nChunksPerBlock,
1483 		     theChunk % dev->nChunksPerBlock)) {
1484 			yaffs_ReadChunkWithTagsFromNAND(dev, theChunk, NULL,
1485 							tags);
1486 			if (yaffs_TagsMatch(tags, objectId, chunkInInode)) {
1487 				/* found it; */
1488 				return theChunk;
1489 
1490 			}
1491 		}
1492 		theChunk++;
1493 	}
1494 	return -1;
1495 }
1496 
1497 static void yaffs_SoftDeleteChunk(yaffs_Device * dev, int chunk)
1498 {
1499 
1500 	yaffs_BlockInfo *theBlock;
1501 
1502 	T(YAFFS_TRACE_DELETION, (TSTR("soft delete chunk %d" TENDSTR), chunk));
1503 
1504 	theBlock = yaffs_GetBlockInfo(dev, chunk / dev->nChunksPerBlock);
1505 	if (theBlock) {
1506 		theBlock->softDeletions++;
1507 		dev->nFreeChunks++;
1508 	}
1509 }
1510 
1511 /* SoftDeleteWorker scans backwards through the tnode tree and soft deletes all the chunks in the file.
1512  * All soft deleting does is increment the block's softdelete count and pulls the chunk out
1513  * of the tnode.
1514  * Thus, essentially this is the same as DeleteWorker except that the chunks are soft deleted.
1515  */
1516 
1517 static int yaffs_SoftDeleteWorker(yaffs_Object * in, yaffs_Tnode * tn,
1518 				  __u32 level, int chunkOffset)
1519 {
1520 	int i;
1521 	int theChunk;
1522 	int allDone = 1;
1523 	yaffs_Device *dev = in->myDev;
1524 
1525 	if (tn) {
1526 		if (level > 0) {
1527 
1528 			for (i = YAFFS_NTNODES_INTERNAL - 1; allDone && i >= 0;
1529 			     i--) {
1530 				if (tn->internal[i]) {
1531 					allDone =
1532 					    yaffs_SoftDeleteWorker(in,
1533 								   tn->
1534 								   internal[i],
1535 								   level - 1,
1536 								   (chunkOffset
1537 								    <<
1538 								    YAFFS_TNODES_INTERNAL_BITS)
1539 								   + i);
1540 					if (allDone) {
1541 						yaffs_FreeTnode(dev,
1542 								tn->
1543 								internal[i]);
1544 						tn->internal[i] = NULL;
1545 					} else {
1546 						/* Hoosterman... how could this happen? */
1547 					}
1548 				}
1549 			}
1550 			return (allDone) ? 1 : 0;
1551 		} else if (level == 0) {
1552 
1553 			for (i = YAFFS_NTNODES_LEVEL0 - 1; i >= 0; i--) {
1554 				theChunk = yaffs_GetChunkGroupBase(dev,tn,i);
1555 				if (theChunk) {
1556 					/* Note this does not find the real chunk, only the chunk group.
1557 					 * We make an assumption that a chunk group is not larger than
1558 					 * a block.
1559 					 */
1560 					yaffs_SoftDeleteChunk(dev, theChunk);
1561 					yaffs_PutLevel0Tnode(dev,tn,i,0);
1562 				}
1563 
1564 			}
1565 			return 1;
1566 
1567 		}
1568 
1569 	}
1570 
1571 	return 1;
1572 
1573 }
1574 
1575 static void yaffs_SoftDeleteFile(yaffs_Object * obj)
1576 {
1577 	if (obj->deleted &&
1578 	    obj->variantType == YAFFS_OBJECT_TYPE_FILE && !obj->softDeleted) {
1579 		if (obj->nDataChunks <= 0) {
1580 			/* Empty file with no duplicate object headers, just delete it immediately */
1581 			yaffs_FreeTnode(obj->myDev,
1582 					obj->variant.fileVariant.top);
1583 			obj->variant.fileVariant.top = NULL;
1584 			T(YAFFS_TRACE_TRACING,
1585 			  (TSTR("yaffs: Deleting empty file %d" TENDSTR),
1586 			   obj->objectId));
1587 			yaffs_DoGenericObjectDeletion(obj);
1588 		} else {
1589 			yaffs_SoftDeleteWorker(obj,
1590 					       obj->variant.fileVariant.top,
1591 					       obj->variant.fileVariant.
1592 					       topLevel, 0);
1593 			obj->softDeleted = 1;
1594 		}
1595 	}
1596 }
1597 
1598 /* Pruning removes any part of the file structure tree that is beyond the
1599  * bounds of the file (ie that does not point to chunks).
1600  *
1601  * A file should only get pruned when its size is reduced.
1602  *
1603  * Before pruning, the chunks must be pulled from the tree and the
1604  * level 0 tnode entries must be zeroed out.
1605  * Could also use this for file deletion, but that's probably better handled
1606  * by a special case.
1607  */
1608 
1609 static yaffs_Tnode *yaffs_PruneWorker(yaffs_Device * dev, yaffs_Tnode * tn,
1610 				      __u32 level, int del0)
1611 {
1612 	int i;
1613 	int hasData;
1614 
1615 	if (tn) {
1616 		hasData = 0;
1617 
1618 		for (i = 0; i < YAFFS_NTNODES_INTERNAL; i++) {
1619 			if (tn->internal[i] && level > 0) {
1620 				tn->internal[i] =
1621 				    yaffs_PruneWorker(dev, tn->internal[i],
1622 						      level - 1,
1623 						      (i == 0) ? del0 : 1);
1624 			}
1625 
1626 			if (tn->internal[i]) {
1627 				hasData++;
1628 			}
1629 		}
1630 
1631 		if (hasData == 0 && del0) {
1632 			/* Free and return NULL */
1633 
1634 			yaffs_FreeTnode(dev, tn);
1635 			tn = NULL;
1636 		}
1637 
1638 	}
1639 
1640 	return tn;
1641 
1642 }
1643 
1644 static int yaffs_PruneFileStructure(yaffs_Device * dev,
1645 				    yaffs_FileStructure * fStruct)
1646 {
1647 	int i;
1648 	int hasData;
1649 	int done = 0;
1650 	yaffs_Tnode *tn;
1651 
1652 	if (fStruct->topLevel > 0) {
1653 		fStruct->top =
1654 		    yaffs_PruneWorker(dev, fStruct->top, fStruct->topLevel, 0);
1655 
1656 		/* Now we have a tree with all the non-zero branches NULL but the height
1657 		 * is the same as it was.
1658 		 * Let's see if we can trim internal tnodes to shorten the tree.
1659 		 * We can do this if only the 0th element in the tnode is in use
1660 		 * (ie all the non-zero are NULL)
1661 		 */
1662 
1663 		while (fStruct->topLevel && !done) {
1664 			tn = fStruct->top;
1665 
1666 			hasData = 0;
1667 			for (i = 1; i < YAFFS_NTNODES_INTERNAL; i++) {
1668 				if (tn->internal[i]) {
1669 					hasData++;
1670 				}
1671 			}
1672 
1673 			if (!hasData) {
1674 				fStruct->top = tn->internal[0];
1675 				fStruct->topLevel--;
1676 				yaffs_FreeTnode(dev, tn);
1677 			} else {
1678 				done = 1;
1679 			}
1680 		}
1681 	}
1682 
1683 	return YAFFS_OK;
1684 }
1685 
1686 /*-------------------- End of File Structure functions.-------------------*/
1687 
1688 /* yaffs_CreateFreeObjects creates a bunch more objects and
1689  * adds them to the object free list.
1690  */
1691 static int yaffs_CreateFreeObjects(yaffs_Device * dev, int nObjects)
1692 {
1693 	int i;
1694 	yaffs_Object *newObjects;
1695 	yaffs_ObjectList *list;
1696 
1697 	if (nObjects < 1)
1698 		return YAFFS_OK;
1699 
1700 	/* make these things */
1701 	newObjects = YMALLOC(nObjects * sizeof(yaffs_Object));
1702 	list = YMALLOC(sizeof(yaffs_ObjectList));
1703 
1704 	if (!newObjects || !list) {
1705 		if(newObjects)
1706 			YFREE(newObjects);
1707 		if(list)
1708 			YFREE(list);
1709 		T(YAFFS_TRACE_ALLOCATE,
1710 		  (TSTR("yaffs: Could not allocate more objects" TENDSTR)));
1711 		return YAFFS_FAIL;
1712 	}
1713 
1714 	/* Hook them into the free list */
1715 	for (i = 0; i < nObjects - 1; i++) {
1716 		newObjects[i].siblings.next =
1717 		    (struct list_head *)(&newObjects[i + 1]);
1718 	}
1719 
1720 	newObjects[nObjects - 1].siblings.next = (void *)dev->freeObjects;
1721 	dev->freeObjects = newObjects;
1722 	dev->nFreeObjects += nObjects;
1723 	dev->nObjectsCreated += nObjects;
1724 
1725 	/* Now add this bunch of Objects to a list for freeing up. */
1726 
1727 	list->objects = newObjects;
1728 	list->next = dev->allocatedObjectList;
1729 	dev->allocatedObjectList = list;
1730 
1731 	return YAFFS_OK;
1732 }
1733 
1734 
1735 /* AllocateEmptyObject gets us a clean Object. Tries to make allocate more if we run out */
1736 static yaffs_Object *yaffs_AllocateEmptyObject(yaffs_Device * dev)
1737 {
1738 	yaffs_Object *tn = NULL;
1739 
1740 	/* If there are none left make more */
1741 	if (!dev->freeObjects) {
1742 		yaffs_CreateFreeObjects(dev, YAFFS_ALLOCATION_NOBJECTS);
1743 	}
1744 
1745 	if (dev->freeObjects) {
1746 		tn = dev->freeObjects;
1747 		dev->freeObjects =
1748 		    (yaffs_Object *) (dev->freeObjects->siblings.next);
1749 		dev->nFreeObjects--;
1750 
1751 		/* Now sweeten it up... */
1752 
1753 		memset(tn, 0, sizeof(yaffs_Object));
1754 		tn->myDev = dev;
1755 		tn->chunkId = -1;
1756 		tn->variantType = YAFFS_OBJECT_TYPE_UNKNOWN;
1757 		INIT_LIST_HEAD(&(tn->hardLinks));
1758 		INIT_LIST_HEAD(&(tn->hashLink));
1759 		INIT_LIST_HEAD(&tn->siblings);
1760 
1761 		/* Add it to the lost and found directory.
1762 		 * NB Can't put root or lostNFound in lostNFound so
1763 		 * check if lostNFound exists first
1764 		 */
1765 		if (dev->lostNFoundDir) {
1766 			yaffs_AddObjectToDirectory(dev->lostNFoundDir, tn);
1767 		}
1768 	}
1769 
1770 	return tn;
1771 }
1772 
1773 static yaffs_Object *yaffs_CreateFakeDirectory(yaffs_Device * dev, int number,
1774 					       __u32 mode)
1775 {
1776 
1777 	yaffs_Object *obj =
1778 	    yaffs_CreateNewObject(dev, number, YAFFS_OBJECT_TYPE_DIRECTORY);
1779 	if (obj) {
1780 		obj->fake = 1;		/* it is fake so it has no NAND presence... */
1781 		obj->renameAllowed = 0;	/* ... and we're not allowed to rename it... */
1782 		obj->unlinkAllowed = 0;	/* ... or unlink it */
1783 		obj->deleted = 0;
1784 		obj->unlinked = 0;
1785 		obj->yst_mode = mode;
1786 		obj->myDev = dev;
1787 		obj->chunkId = 0;	/* Not a valid chunk. */
1788 	}
1789 
1790 	return obj;
1791 
1792 }
1793 
1794 static void yaffs_UnhashObject(yaffs_Object * tn)
1795 {
1796 	int bucket;
1797 	yaffs_Device *dev = tn->myDev;
1798 
1799 	/* If it is still linked into the bucket list, free from the list */
1800 	if (!list_empty(&tn->hashLink)) {
1801 		list_del_init(&tn->hashLink);
1802 		bucket = yaffs_HashFunction(tn->objectId);
1803 		dev->objectBucket[bucket].count--;
1804 	}
1805 
1806 }
1807 
1808 /*  FreeObject frees up a Object and puts it back on the free list */
1809 static void yaffs_FreeObject(yaffs_Object * tn)
1810 {
1811 
1812 	yaffs_Device *dev = tn->myDev;
1813 
1814 /* XXX U-BOOT XXX */
1815 #if 0
1816 #ifdef  __KERNEL__
1817 	if (tn->myInode) {
1818 		/* We're still hooked up to a cached inode.
1819 		 * Don't delete now, but mark for later deletion
1820 		 */
1821 		tn->deferedFree = 1;
1822 		return;
1823 	}
1824 #endif
1825 #endif
1826 	yaffs_UnhashObject(tn);
1827 
1828 	/* Link into the free list. */
1829 	tn->siblings.next = (struct list_head *)(dev->freeObjects);
1830 	dev->freeObjects = tn;
1831 	dev->nFreeObjects++;
1832 }
1833 
1834 /* XXX U-BOOT XXX */
1835 #if 0
1836 #ifdef __KERNEL__
1837 
1838 void yaffs_HandleDeferedFree(yaffs_Object * obj)
1839 {
1840 	if (obj->deferedFree) {
1841 		yaffs_FreeObject(obj);
1842 	}
1843 }
1844 
1845 #endif
1846 #endif
1847 
1848 static void yaffs_DeinitialiseObjects(yaffs_Device * dev)
1849 {
1850 	/* Free the list of allocated Objects */
1851 
1852 	yaffs_ObjectList *tmp;
1853 
1854 	while (dev->allocatedObjectList) {
1855 		tmp = dev->allocatedObjectList->next;
1856 		YFREE(dev->allocatedObjectList->objects);
1857 		YFREE(dev->allocatedObjectList);
1858 
1859 		dev->allocatedObjectList = tmp;
1860 	}
1861 
1862 	dev->freeObjects = NULL;
1863 	dev->nFreeObjects = 0;
1864 }
1865 
1866 static void yaffs_InitialiseObjects(yaffs_Device * dev)
1867 {
1868 	int i;
1869 
1870 	dev->allocatedObjectList = NULL;
1871 	dev->freeObjects = NULL;
1872 	dev->nFreeObjects = 0;
1873 
1874 	for (i = 0; i < YAFFS_NOBJECT_BUCKETS; i++) {
1875 		INIT_LIST_HEAD(&dev->objectBucket[i].list);
1876 		dev->objectBucket[i].count = 0;
1877 	}
1878 
1879 }
1880 
1881 static int yaffs_FindNiceObjectBucket(yaffs_Device * dev)
1882 {
1883 	static int x = 0;
1884 	int i;
1885 	int l = 999;
1886 	int lowest = 999999;
1887 
1888 	/* First let's see if we can find one that's empty. */
1889 
1890 	for (i = 0; i < 10 && lowest > 0; i++) {
1891 		x++;
1892 		x %= YAFFS_NOBJECT_BUCKETS;
1893 		if (dev->objectBucket[x].count < lowest) {
1894 			lowest = dev->objectBucket[x].count;
1895 			l = x;
1896 		}
1897 
1898 	}
1899 
1900 	/* If we didn't find an empty list, then try
1901 	 * looking a bit further for a short one
1902 	 */
1903 
1904 	for (i = 0; i < 10 && lowest > 3; i++) {
1905 		x++;
1906 		x %= YAFFS_NOBJECT_BUCKETS;
1907 		if (dev->objectBucket[x].count < lowest) {
1908 			lowest = dev->objectBucket[x].count;
1909 			l = x;
1910 		}
1911 
1912 	}
1913 
1914 	return l;
1915 }
1916 
1917 static int yaffs_CreateNewObjectNumber(yaffs_Device * dev)
1918 {
1919 	int bucket = yaffs_FindNiceObjectBucket(dev);
1920 
1921 	/* Now find an object value that has not already been taken
1922 	 * by scanning the list.
1923 	 */
1924 
1925 	int found = 0;
1926 	struct list_head *i;
1927 
1928 	__u32 n = (__u32) bucket;
1929 
1930 	/* yaffs_CheckObjectHashSanity();  */
1931 
1932 	while (!found) {
1933 		found = 1;
1934 		n += YAFFS_NOBJECT_BUCKETS;
1935 		if (1 || dev->objectBucket[bucket].count > 0) {
1936 			list_for_each(i, &dev->objectBucket[bucket].list) {
1937 				/* If there is already one in the list */
1938 				if (i
1939 				    && list_entry(i, yaffs_Object,
1940 						  hashLink)->objectId == n) {
1941 					found = 0;
1942 				}
1943 			}
1944 		}
1945 	}
1946 
1947 
1948 	return n;
1949 }
1950 
1951 static void yaffs_HashObject(yaffs_Object * in)
1952 {
1953 	int bucket = yaffs_HashFunction(in->objectId);
1954 	yaffs_Device *dev = in->myDev;
1955 
1956 	list_add(&in->hashLink, &dev->objectBucket[bucket].list);
1957 	dev->objectBucket[bucket].count++;
1958 
1959 }
1960 
1961 yaffs_Object *yaffs_FindObjectByNumber(yaffs_Device * dev, __u32 number)
1962 {
1963 	int bucket = yaffs_HashFunction(number);
1964 	struct list_head *i;
1965 	yaffs_Object *in;
1966 
1967 	list_for_each(i, &dev->objectBucket[bucket].list) {
1968 		/* Look if it is in the list */
1969 		if (i) {
1970 			in = list_entry(i, yaffs_Object, hashLink);
1971 			if (in->objectId == number) {
1972 /* XXX U-BOOT XXX */
1973 #if 0
1974 #ifdef __KERNEL__
1975 				/* Don't tell the VFS about this one if it is defered free */
1976 				if (in->deferedFree)
1977 					return NULL;
1978 #endif
1979 #endif
1980 				return in;
1981 			}
1982 		}
1983 	}
1984 
1985 	return NULL;
1986 }
1987 
1988 yaffs_Object *yaffs_CreateNewObject(yaffs_Device * dev, int number,
1989 				    yaffs_ObjectType type)
1990 {
1991 
1992 	yaffs_Object *theObject;
1993 	yaffs_Tnode *tn = NULL;
1994 
1995 	if (number < 0) {
1996 		number = yaffs_CreateNewObjectNumber(dev);
1997 	}
1998 
1999 	theObject = yaffs_AllocateEmptyObject(dev);
2000 	if(!theObject)
2001 		return NULL;
2002 
2003 	if(type == YAFFS_OBJECT_TYPE_FILE){
2004 		tn = yaffs_GetTnode(dev);
2005 		if(!tn){
2006 			yaffs_FreeObject(theObject);
2007 			return NULL;
2008 		}
2009 	}
2010 
2011 
2012 
2013 	if (theObject) {
2014 		theObject->fake = 0;
2015 		theObject->renameAllowed = 1;
2016 		theObject->unlinkAllowed = 1;
2017 		theObject->objectId = number;
2018 		yaffs_HashObject(theObject);
2019 		theObject->variantType = type;
2020 #ifdef CONFIG_YAFFS_WINCE
2021 		yfsd_WinFileTimeNow(theObject->win_atime);
2022 		theObject->win_ctime[0] = theObject->win_mtime[0] =
2023 		    theObject->win_atime[0];
2024 		theObject->win_ctime[1] = theObject->win_mtime[1] =
2025 		    theObject->win_atime[1];
2026 
2027 #else
2028 
2029 		theObject->yst_atime = theObject->yst_mtime =
2030 		    theObject->yst_ctime = Y_CURRENT_TIME;
2031 #endif
2032 		switch (type) {
2033 		case YAFFS_OBJECT_TYPE_FILE:
2034 			theObject->variant.fileVariant.fileSize = 0;
2035 			theObject->variant.fileVariant.scannedFileSize = 0;
2036 			theObject->variant.fileVariant.shrinkSize = 0xFFFFFFFF;	/* max __u32 */
2037 			theObject->variant.fileVariant.topLevel = 0;
2038 			theObject->variant.fileVariant.top = tn;
2039 			break;
2040 		case YAFFS_OBJECT_TYPE_DIRECTORY:
2041 			INIT_LIST_HEAD(&theObject->variant.directoryVariant.
2042 				       children);
2043 			break;
2044 		case YAFFS_OBJECT_TYPE_SYMLINK:
2045 		case YAFFS_OBJECT_TYPE_HARDLINK:
2046 		case YAFFS_OBJECT_TYPE_SPECIAL:
2047 			/* No action required */
2048 			break;
2049 		case YAFFS_OBJECT_TYPE_UNKNOWN:
2050 			/* todo this should not happen */
2051 			break;
2052 		}
2053 	}
2054 
2055 	return theObject;
2056 }
2057 
2058 static yaffs_Object *yaffs_FindOrCreateObjectByNumber(yaffs_Device * dev,
2059 						      int number,
2060 						      yaffs_ObjectType type)
2061 {
2062 	yaffs_Object *theObject = NULL;
2063 
2064 	if (number > 0) {
2065 		theObject = yaffs_FindObjectByNumber(dev, number);
2066 	}
2067 
2068 	if (!theObject) {
2069 		theObject = yaffs_CreateNewObject(dev, number, type);
2070 	}
2071 
2072 	return theObject;
2073 
2074 }
2075 
2076 
2077 static YCHAR *yaffs_CloneString(const YCHAR * str)
2078 {
2079 	YCHAR *newStr = NULL;
2080 
2081 	if (str && *str) {
2082 		newStr = YMALLOC((yaffs_strlen(str) + 1) * sizeof(YCHAR));
2083 		if(newStr)
2084 			yaffs_strcpy(newStr, str);
2085 	}
2086 
2087 	return newStr;
2088 
2089 }
2090 
2091 /*
2092  * Mknod (create) a new object.
2093  * equivalentObject only has meaning for a hard link;
2094  * aliasString only has meaning for a sumlink.
2095  * rdev only has meaning for devices (a subset of special objects)
2096  */
2097 
2098 static yaffs_Object *yaffs_MknodObject(yaffs_ObjectType type,
2099 				       yaffs_Object * parent,
2100 				       const YCHAR * name,
2101 				       __u32 mode,
2102 				       __u32 uid,
2103 				       __u32 gid,
2104 				       yaffs_Object * equivalentObject,
2105 				       const YCHAR * aliasString, __u32 rdev)
2106 {
2107 	yaffs_Object *in;
2108 	YCHAR *str = NULL;
2109 
2110 	yaffs_Device *dev = parent->myDev;
2111 
2112 	/* Check if the entry exists. If it does then fail the call since we don't want a dup.*/
2113 	if (yaffs_FindObjectByName(parent, name)) {
2114 		return NULL;
2115 	}
2116 
2117 	in = yaffs_CreateNewObject(dev, -1, type);
2118 
2119 	if(type == YAFFS_OBJECT_TYPE_SYMLINK){
2120 		str = yaffs_CloneString(aliasString);
2121 		if(!str){
2122 			yaffs_FreeObject(in);
2123 			return NULL;
2124 		}
2125 	}
2126 
2127 
2128 
2129 	if (in) {
2130 		in->chunkId = -1;
2131 		in->valid = 1;
2132 		in->variantType = type;
2133 
2134 		in->yst_mode = mode;
2135 
2136 #ifdef CONFIG_YAFFS_WINCE
2137 		yfsd_WinFileTimeNow(in->win_atime);
2138 		in->win_ctime[0] = in->win_mtime[0] = in->win_atime[0];
2139 		in->win_ctime[1] = in->win_mtime[1] = in->win_atime[1];
2140 
2141 #else
2142 		in->yst_atime = in->yst_mtime = in->yst_ctime = Y_CURRENT_TIME;
2143 
2144 		in->yst_rdev = rdev;
2145 		in->yst_uid = uid;
2146 		in->yst_gid = gid;
2147 #endif
2148 		in->nDataChunks = 0;
2149 
2150 		yaffs_SetObjectName(in, name);
2151 		in->dirty = 1;
2152 
2153 		yaffs_AddObjectToDirectory(parent, in);
2154 
2155 		in->myDev = parent->myDev;
2156 
2157 		switch (type) {
2158 		case YAFFS_OBJECT_TYPE_SYMLINK:
2159 			in->variant.symLinkVariant.alias = str;
2160 			break;
2161 		case YAFFS_OBJECT_TYPE_HARDLINK:
2162 			in->variant.hardLinkVariant.equivalentObject =
2163 			    equivalentObject;
2164 			in->variant.hardLinkVariant.equivalentObjectId =
2165 			    equivalentObject->objectId;
2166 			list_add(&in->hardLinks, &equivalentObject->hardLinks);
2167 			break;
2168 		case YAFFS_OBJECT_TYPE_FILE:
2169 		case YAFFS_OBJECT_TYPE_DIRECTORY:
2170 		case YAFFS_OBJECT_TYPE_SPECIAL:
2171 		case YAFFS_OBJECT_TYPE_UNKNOWN:
2172 			/* do nothing */
2173 			break;
2174 		}
2175 
2176 		if (yaffs_UpdateObjectHeader(in, name, 0, 0, 0) < 0) {
2177 			/* Could not create the object header, fail the creation */
2178 			yaffs_DestroyObject(in);
2179 			in = NULL;
2180 		}
2181 
2182 	}
2183 
2184 	return in;
2185 }
2186 
2187 yaffs_Object *yaffs_MknodFile(yaffs_Object * parent, const YCHAR * name,
2188 			      __u32 mode, __u32 uid, __u32 gid)
2189 {
2190 	return yaffs_MknodObject(YAFFS_OBJECT_TYPE_FILE, parent, name, mode,
2191 				 uid, gid, NULL, NULL, 0);
2192 }
2193 
2194 yaffs_Object *yaffs_MknodDirectory(yaffs_Object * parent, const YCHAR * name,
2195 				   __u32 mode, __u32 uid, __u32 gid)
2196 {
2197 	return yaffs_MknodObject(YAFFS_OBJECT_TYPE_DIRECTORY, parent, name,
2198 				 mode, uid, gid, NULL, NULL, 0);
2199 }
2200 
2201 yaffs_Object *yaffs_MknodSpecial(yaffs_Object * parent, const YCHAR * name,
2202 				 __u32 mode, __u32 uid, __u32 gid, __u32 rdev)
2203 {
2204 	return yaffs_MknodObject(YAFFS_OBJECT_TYPE_SPECIAL, parent, name, mode,
2205 				 uid, gid, NULL, NULL, rdev);
2206 }
2207 
2208 yaffs_Object *yaffs_MknodSymLink(yaffs_Object * parent, const YCHAR * name,
2209 				 __u32 mode, __u32 uid, __u32 gid,
2210 				 const YCHAR * alias)
2211 {
2212 	return yaffs_MknodObject(YAFFS_OBJECT_TYPE_SYMLINK, parent, name, mode,
2213 				 uid, gid, NULL, alias, 0);
2214 }
2215 
2216 /* yaffs_Link returns the object id of the equivalent object.*/
2217 yaffs_Object *yaffs_Link(yaffs_Object * parent, const YCHAR * name,
2218 			 yaffs_Object * equivalentObject)
2219 {
2220 	/* Get the real object in case we were fed a hard link as an equivalent object */
2221 	equivalentObject = yaffs_GetEquivalentObject(equivalentObject);
2222 
2223 	if (yaffs_MknodObject
2224 	    (YAFFS_OBJECT_TYPE_HARDLINK, parent, name, 0, 0, 0,
2225 	     equivalentObject, NULL, 0)) {
2226 		return equivalentObject;
2227 	} else {
2228 		return NULL;
2229 	}
2230 
2231 }
2232 
2233 static int yaffs_ChangeObjectName(yaffs_Object * obj, yaffs_Object * newDir,
2234 				  const YCHAR * newName, int force, int shadows)
2235 {
2236 	int unlinkOp;
2237 	int deleteOp;
2238 
2239 	yaffs_Object *existingTarget;
2240 
2241 	if (newDir == NULL) {
2242 		newDir = obj->parent;	/* use the old directory */
2243 	}
2244 
2245 	if (newDir->variantType != YAFFS_OBJECT_TYPE_DIRECTORY) {
2246 		T(YAFFS_TRACE_ALWAYS,
2247 		  (TSTR
2248 		   ("tragendy: yaffs_ChangeObjectName: newDir is not a directory"
2249 		    TENDSTR)));
2250 		YBUG();
2251 	}
2252 
2253 	/* TODO: Do we need this different handling for YAFFS2 and YAFFS1?? */
2254 	if (obj->myDev->isYaffs2) {
2255 		unlinkOp = (newDir == obj->myDev->unlinkedDir);
2256 	} else {
2257 		unlinkOp = (newDir == obj->myDev->unlinkedDir
2258 			    && obj->variantType == YAFFS_OBJECT_TYPE_FILE);
2259 	}
2260 
2261 	deleteOp = (newDir == obj->myDev->deletedDir);
2262 
2263 	existingTarget = yaffs_FindObjectByName(newDir, newName);
2264 
2265 	/* If the object is a file going into the unlinked directory,
2266 	 *   then it is OK to just stuff it in since duplicate names are allowed.
2267 	 *   else only proceed if the new name does not exist and if we're putting
2268 	 *   it into a directory.
2269 	 */
2270 	if ((unlinkOp ||
2271 	     deleteOp ||
2272 	     force ||
2273 	     (shadows > 0) ||
2274 	     !existingTarget) &&
2275 	    newDir->variantType == YAFFS_OBJECT_TYPE_DIRECTORY) {
2276 		yaffs_SetObjectName(obj, newName);
2277 		obj->dirty = 1;
2278 
2279 		yaffs_AddObjectToDirectory(newDir, obj);
2280 
2281 		if (unlinkOp)
2282 			obj->unlinked = 1;
2283 
2284 		/* If it is a deletion then we mark it as a shrink for gc purposes. */
2285 		if (yaffs_UpdateObjectHeader(obj, newName, 0, deleteOp, shadows)>= 0)
2286 			return YAFFS_OK;
2287 	}
2288 
2289 	return YAFFS_FAIL;
2290 }
2291 
2292 int yaffs_RenameObject(yaffs_Object * oldDir, const YCHAR * oldName,
2293 		       yaffs_Object * newDir, const YCHAR * newName)
2294 {
2295 	yaffs_Object *obj;
2296 	yaffs_Object *existingTarget;
2297 	int force = 0;
2298 
2299 #ifdef CONFIG_YAFFS_CASE_INSENSITIVE
2300 	/* Special case for case insemsitive systems (eg. WinCE).
2301 	 * While look-up is case insensitive, the name isn't.
2302 	 * Therefore we might want to change x.txt to X.txt
2303 	*/
2304 	if (oldDir == newDir && yaffs_strcmp(oldName, newName) == 0) {
2305 		force = 1;
2306 	}
2307 #endif
2308 
2309 	obj = yaffs_FindObjectByName(oldDir, oldName);
2310 	/* Check new name to long. */
2311 	if (obj->variantType == YAFFS_OBJECT_TYPE_SYMLINK &&
2312 	    yaffs_strlen(newName) > YAFFS_MAX_ALIAS_LENGTH)
2313 	  /* ENAMETOOLONG */
2314 	  return YAFFS_FAIL;
2315 	else if (obj->variantType != YAFFS_OBJECT_TYPE_SYMLINK &&
2316 		 yaffs_strlen(newName) > YAFFS_MAX_NAME_LENGTH)
2317 	  /* ENAMETOOLONG */
2318 	  return YAFFS_FAIL;
2319 
2320 	if (obj && obj->renameAllowed) {
2321 
2322 		/* Now do the handling for an existing target, if there is one */
2323 
2324 		existingTarget = yaffs_FindObjectByName(newDir, newName);
2325 		if (existingTarget &&
2326 		    existingTarget->variantType == YAFFS_OBJECT_TYPE_DIRECTORY &&
2327 		    !list_empty(&existingTarget->variant.directoryVariant.children)) {
2328 			/* There is a target that is a non-empty directory, so we fail */
2329 			return YAFFS_FAIL;	/* EEXIST or ENOTEMPTY */
2330 		} else if (existingTarget && existingTarget != obj) {
2331 			/* Nuke the target first, using shadowing,
2332 			 * but only if it isn't the same object
2333 			 */
2334 			yaffs_ChangeObjectName(obj, newDir, newName, force,
2335 					       existingTarget->objectId);
2336 			yaffs_UnlinkObject(existingTarget);
2337 		}
2338 
2339 		return yaffs_ChangeObjectName(obj, newDir, newName, 1, 0);
2340 	}
2341 	return YAFFS_FAIL;
2342 }
2343 
2344 /*------------------------- Block Management and Page Allocation ----------------*/
2345 
2346 static int yaffs_InitialiseBlocks(yaffs_Device * dev)
2347 {
2348 	int nBlocks = dev->internalEndBlock - dev->internalStartBlock + 1;
2349 
2350 	dev->blockInfo = NULL;
2351 	dev->chunkBits = NULL;
2352 
2353 	dev->allocationBlock = -1;	/* force it to get a new one */
2354 
2355 	/* If the first allocation strategy fails, thry the alternate one */
2356 	dev->blockInfo = YMALLOC(nBlocks * sizeof(yaffs_BlockInfo));
2357 	if(!dev->blockInfo){
2358 		dev->blockInfo = YMALLOC_ALT(nBlocks * sizeof(yaffs_BlockInfo));
2359 		dev->blockInfoAlt = 1;
2360 	}
2361 	else
2362 		dev->blockInfoAlt = 0;
2363 
2364 	if(dev->blockInfo){
2365 
2366 		/* Set up dynamic blockinfo stuff. */
2367 		dev->chunkBitmapStride = (dev->nChunksPerBlock + 7) / 8; /* round up bytes */
2368 		dev->chunkBits = YMALLOC(dev->chunkBitmapStride * nBlocks);
2369 		if(!dev->chunkBits){
2370 			dev->chunkBits = YMALLOC_ALT(dev->chunkBitmapStride * nBlocks);
2371 			dev->chunkBitsAlt = 1;
2372 		}
2373 		else
2374 			dev->chunkBitsAlt = 0;
2375 	}
2376 
2377 	if (dev->blockInfo && dev->chunkBits) {
2378 		memset(dev->blockInfo, 0, nBlocks * sizeof(yaffs_BlockInfo));
2379 		memset(dev->chunkBits, 0, dev->chunkBitmapStride * nBlocks);
2380 		return YAFFS_OK;
2381 	}
2382 
2383 	return YAFFS_FAIL;
2384 
2385 }
2386 
2387 static void yaffs_DeinitialiseBlocks(yaffs_Device * dev)
2388 {
2389 	if(dev->blockInfoAlt && dev->blockInfo)
2390 		YFREE_ALT(dev->blockInfo);
2391 	else if(dev->blockInfo)
2392 		YFREE(dev->blockInfo);
2393 
2394 	dev->blockInfoAlt = 0;
2395 
2396 	dev->blockInfo = NULL;
2397 
2398 	if(dev->chunkBitsAlt && dev->chunkBits)
2399 		YFREE_ALT(dev->chunkBits);
2400 	else if(dev->chunkBits)
2401 		YFREE(dev->chunkBits);
2402 	dev->chunkBitsAlt = 0;
2403 	dev->chunkBits = NULL;
2404 }
2405 
2406 static int yaffs_BlockNotDisqualifiedFromGC(yaffs_Device * dev,
2407 					    yaffs_BlockInfo * bi)
2408 {
2409 	int i;
2410 	__u32 seq;
2411 	yaffs_BlockInfo *b;
2412 
2413 	if (!dev->isYaffs2)
2414 		return 1;	/* disqualification only applies to yaffs2. */
2415 
2416 	if (!bi->hasShrinkHeader)
2417 		return 1;	/* can gc */
2418 
2419 	/* Find the oldest dirty sequence number if we don't know it and save it
2420 	 * so we don't have to keep recomputing it.
2421 	 */
2422 	if (!dev->oldestDirtySequence) {
2423 		seq = dev->sequenceNumber;
2424 
2425 		for (i = dev->internalStartBlock; i <= dev->internalEndBlock;
2426 		     i++) {
2427 			b = yaffs_GetBlockInfo(dev, i);
2428 			if (b->blockState == YAFFS_BLOCK_STATE_FULL &&
2429 			    (b->pagesInUse - b->softDeletions) <
2430 			    dev->nChunksPerBlock && b->sequenceNumber < seq) {
2431 				seq = b->sequenceNumber;
2432 			}
2433 		}
2434 		dev->oldestDirtySequence = seq;
2435 	}
2436 
2437 	/* Can't do gc of this block if there are any blocks older than this one that have
2438 	 * discarded pages.
2439 	 */
2440 	return (bi->sequenceNumber <= dev->oldestDirtySequence);
2441 
2442 }
2443 
2444 /* FindDiretiestBlock is used to select the dirtiest block (or close enough)
2445  * for garbage collection.
2446  */
2447 
2448 static int yaffs_FindBlockForGarbageCollection(yaffs_Device * dev,
2449 					       int aggressive)
2450 {
2451 
2452 	int b = dev->currentDirtyChecker;
2453 
2454 	int i;
2455 	int iterations;
2456 	int dirtiest = -1;
2457 	int pagesInUse = 0;
2458 	int prioritised=0;
2459 	yaffs_BlockInfo *bi;
2460 	int pendingPrioritisedExist = 0;
2461 
2462 	/* First let's see if we need to grab a prioritised block */
2463 	if(dev->hasPendingPrioritisedGCs){
2464 		for(i = dev->internalStartBlock; i < dev->internalEndBlock && !prioritised; i++){
2465 
2466 			bi = yaffs_GetBlockInfo(dev, i);
2467 			//yaffs_VerifyBlock(dev,bi,i);
2468 
2469 			if(bi->gcPrioritise) {
2470 				pendingPrioritisedExist = 1;
2471 				if(bi->blockState == YAFFS_BLOCK_STATE_FULL &&
2472 				   yaffs_BlockNotDisqualifiedFromGC(dev, bi)){
2473 					pagesInUse = (bi->pagesInUse - bi->softDeletions);
2474 					dirtiest = i;
2475 					prioritised = 1;
2476 					aggressive = 1; /* Fool the non-aggressive skip logiv below */
2477 				}
2478 			}
2479 		}
2480 
2481 		if(!pendingPrioritisedExist) /* None found, so we can clear this */
2482 			dev->hasPendingPrioritisedGCs = 0;
2483 	}
2484 
2485 	/* If we're doing aggressive GC then we are happy to take a less-dirty block, and
2486 	 * search harder.
2487 	 * else (we're doing a leasurely gc), then we only bother to do this if the
2488 	 * block has only a few pages in use.
2489 	 */
2490 
2491 	dev->nonAggressiveSkip--;
2492 
2493 	if (!aggressive && (dev->nonAggressiveSkip > 0)) {
2494 		return -1;
2495 	}
2496 
2497 	if(!prioritised)
2498 		pagesInUse =
2499 			(aggressive) ? dev->nChunksPerBlock : YAFFS_PASSIVE_GC_CHUNKS + 1;
2500 
2501 	if (aggressive) {
2502 		iterations =
2503 		    dev->internalEndBlock - dev->internalStartBlock + 1;
2504 	} else {
2505 		iterations =
2506 		    dev->internalEndBlock - dev->internalStartBlock + 1;
2507 		iterations = iterations / 16;
2508 		if (iterations > 200) {
2509 			iterations = 200;
2510 		}
2511 	}
2512 
2513 	for (i = 0; i <= iterations && pagesInUse > 0 && !prioritised; i++) {
2514 		b++;
2515 		if (b < dev->internalStartBlock || b > dev->internalEndBlock) {
2516 			b = dev->internalStartBlock;
2517 		}
2518 
2519 		if (b < dev->internalStartBlock || b > dev->internalEndBlock) {
2520 			T(YAFFS_TRACE_ERROR,
2521 			  (TSTR("**>> Block %d is not valid" TENDSTR), b));
2522 			YBUG();
2523 		}
2524 
2525 		bi = yaffs_GetBlockInfo(dev, b);
2526 
2527 #if 0
2528 		if (bi->blockState == YAFFS_BLOCK_STATE_CHECKPOINT) {
2529 			dirtiest = b;
2530 			pagesInUse = 0;
2531 		}
2532 		else
2533 #endif
2534 
2535 		if (bi->blockState == YAFFS_BLOCK_STATE_FULL &&
2536 		       (bi->pagesInUse - bi->softDeletions) < pagesInUse &&
2537 			yaffs_BlockNotDisqualifiedFromGC(dev, bi)) {
2538 			dirtiest = b;
2539 			pagesInUse = (bi->pagesInUse - bi->softDeletions);
2540 		}
2541 	}
2542 
2543 	dev->currentDirtyChecker = b;
2544 
2545 	if (dirtiest > 0) {
2546 		T(YAFFS_TRACE_GC,
2547 		  (TSTR("GC Selected block %d with %d free, prioritised:%d" TENDSTR), dirtiest,
2548 		   dev->nChunksPerBlock - pagesInUse,prioritised));
2549 	}
2550 
2551 	dev->oldestDirtySequence = 0;
2552 
2553 	if (dirtiest > 0) {
2554 		dev->nonAggressiveSkip = 4;
2555 	}
2556 
2557 	return dirtiest;
2558 }
2559 
2560 static void yaffs_BlockBecameDirty(yaffs_Device * dev, int blockNo)
2561 {
2562 	yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, blockNo);
2563 
2564 	int erasedOk = 0;
2565 
2566 	/* If the block is still healthy erase it and mark as clean.
2567 	 * If the block has had a data failure, then retire it.
2568 	 */
2569 
2570 	T(YAFFS_TRACE_GC | YAFFS_TRACE_ERASE,
2571 		(TSTR("yaffs_BlockBecameDirty block %d state %d %s"TENDSTR),
2572 		blockNo, bi->blockState, (bi->needsRetiring) ? "needs retiring" : ""));
2573 
2574 	bi->blockState = YAFFS_BLOCK_STATE_DIRTY;
2575 
2576 	if (!bi->needsRetiring) {
2577 		yaffs_InvalidateCheckpoint(dev);
2578 		erasedOk = yaffs_EraseBlockInNAND(dev, blockNo);
2579 		if (!erasedOk) {
2580 			dev->nErasureFailures++;
2581 			T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
2582 			  (TSTR("**>> Erasure failed %d" TENDSTR), blockNo));
2583 		}
2584 	}
2585 
2586 	if (erasedOk &&
2587 	    ((yaffs_traceMask & YAFFS_TRACE_ERASE) || !yaffs_SkipVerification(dev))) {
2588 		int i;
2589 		for (i = 0; i < dev->nChunksPerBlock; i++) {
2590 			if (!yaffs_CheckChunkErased
2591 			    (dev, blockNo * dev->nChunksPerBlock + i)) {
2592 				T(YAFFS_TRACE_ERROR,
2593 				  (TSTR
2594 				   (">>Block %d erasure supposedly OK, but chunk %d not erased"
2595 				    TENDSTR), blockNo, i));
2596 			}
2597 		}
2598 	}
2599 
2600 	if (erasedOk) {
2601 		/* Clean it up... */
2602 		bi->blockState = YAFFS_BLOCK_STATE_EMPTY;
2603 		dev->nErasedBlocks++;
2604 		bi->pagesInUse = 0;
2605 		bi->softDeletions = 0;
2606 		bi->hasShrinkHeader = 0;
2607 		bi->skipErasedCheck = 1;  /* This is clean, so no need to check */
2608 		bi->gcPrioritise = 0;
2609 		yaffs_ClearChunkBits(dev, blockNo);
2610 
2611 		T(YAFFS_TRACE_ERASE,
2612 		  (TSTR("Erased block %d" TENDSTR), blockNo));
2613 	} else {
2614 		dev->nFreeChunks -= dev->nChunksPerBlock;	/* We lost a block of free space */
2615 
2616 		yaffs_RetireBlock(dev, blockNo);
2617 		T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
2618 		  (TSTR("**>> Block %d retired" TENDSTR), blockNo));
2619 	}
2620 }
2621 
2622 static int yaffs_FindBlockForAllocation(yaffs_Device * dev)
2623 {
2624 	int i;
2625 
2626 	yaffs_BlockInfo *bi;
2627 
2628 	if (dev->nErasedBlocks < 1) {
2629 		/* Hoosterman we've got a problem.
2630 		 * Can't get space to gc
2631 		 */
2632 		T(YAFFS_TRACE_ERROR,
2633 		  (TSTR("yaffs tragedy: no more eraased blocks" TENDSTR)));
2634 
2635 		return -1;
2636 	}
2637 
2638 	/* Find an empty block. */
2639 
2640 	for (i = dev->internalStartBlock; i <= dev->internalEndBlock; i++) {
2641 		dev->allocationBlockFinder++;
2642 		if (dev->allocationBlockFinder < dev->internalStartBlock
2643 		    || dev->allocationBlockFinder > dev->internalEndBlock) {
2644 			dev->allocationBlockFinder = dev->internalStartBlock;
2645 		}
2646 
2647 		bi = yaffs_GetBlockInfo(dev, dev->allocationBlockFinder);
2648 
2649 		if (bi->blockState == YAFFS_BLOCK_STATE_EMPTY) {
2650 			bi->blockState = YAFFS_BLOCK_STATE_ALLOCATING;
2651 			dev->sequenceNumber++;
2652 			bi->sequenceNumber = dev->sequenceNumber;
2653 			dev->nErasedBlocks--;
2654 			T(YAFFS_TRACE_ALLOCATE,
2655 			  (TSTR("Allocated block %d, seq  %d, %d left" TENDSTR),
2656 			   dev->allocationBlockFinder, dev->sequenceNumber,
2657 			   dev->nErasedBlocks));
2658 			return dev->allocationBlockFinder;
2659 		}
2660 	}
2661 
2662 	T(YAFFS_TRACE_ALWAYS,
2663 	  (TSTR
2664 	   ("yaffs tragedy: no more eraased blocks, but there should have been %d"
2665 	    TENDSTR), dev->nErasedBlocks));
2666 
2667 	return -1;
2668 }
2669 
2670 
2671 // Check if there's space to allocate...
2672 // Thinks.... do we need top make this ths same as yaffs_GetFreeChunks()?
2673 static int yaffs_CheckSpaceForAllocation(yaffs_Device * dev)
2674 {
2675 	int reservedChunks;
2676 	int reservedBlocks = dev->nReservedBlocks;
2677 	int checkpointBlocks;
2678 
2679 	checkpointBlocks =  dev->nCheckpointReservedBlocks - dev->blocksInCheckpoint;
2680 	if(checkpointBlocks < 0)
2681 		checkpointBlocks = 0;
2682 
2683 	reservedChunks = ((reservedBlocks + checkpointBlocks) * dev->nChunksPerBlock);
2684 
2685 	return (dev->nFreeChunks > reservedChunks);
2686 }
2687 
2688 static int yaffs_AllocateChunk(yaffs_Device * dev, int useReserve, yaffs_BlockInfo **blockUsedPtr)
2689 {
2690 	int retVal;
2691 	yaffs_BlockInfo *bi;
2692 
2693 	if (dev->allocationBlock < 0) {
2694 		/* Get next block to allocate off */
2695 		dev->allocationBlock = yaffs_FindBlockForAllocation(dev);
2696 		dev->allocationPage = 0;
2697 	}
2698 
2699 	if (!useReserve && !yaffs_CheckSpaceForAllocation(dev)) {
2700 		/* Not enough space to allocate unless we're allowed to use the reserve. */
2701 		return -1;
2702 	}
2703 
2704 	if (dev->nErasedBlocks < dev->nReservedBlocks
2705 	    && dev->allocationPage == 0) {
2706 		T(YAFFS_TRACE_ALLOCATE, (TSTR("Allocating reserve" TENDSTR)));
2707 	}
2708 
2709 	/* Next page please.... */
2710 	if (dev->allocationBlock >= 0) {
2711 		bi = yaffs_GetBlockInfo(dev, dev->allocationBlock);
2712 
2713 		retVal = (dev->allocationBlock * dev->nChunksPerBlock) +
2714 		    dev->allocationPage;
2715 		bi->pagesInUse++;
2716 		yaffs_SetChunkBit(dev, dev->allocationBlock,
2717 				  dev->allocationPage);
2718 
2719 		dev->allocationPage++;
2720 
2721 		dev->nFreeChunks--;
2722 
2723 		/* If the block is full set the state to full */
2724 		if (dev->allocationPage >= dev->nChunksPerBlock) {
2725 			bi->blockState = YAFFS_BLOCK_STATE_FULL;
2726 			dev->allocationBlock = -1;
2727 		}
2728 
2729 		if(blockUsedPtr)
2730 			*blockUsedPtr = bi;
2731 
2732 		return retVal;
2733 	}
2734 
2735 	T(YAFFS_TRACE_ERROR,
2736 	  (TSTR("!!!!!!!!! Allocator out !!!!!!!!!!!!!!!!!" TENDSTR)));
2737 
2738 	return -1;
2739 }
2740 
2741 static int yaffs_GetErasedChunks(yaffs_Device * dev)
2742 {
2743 	int n;
2744 
2745 	n = dev->nErasedBlocks * dev->nChunksPerBlock;
2746 
2747 	if (dev->allocationBlock > 0) {
2748 		n += (dev->nChunksPerBlock - dev->allocationPage);
2749 	}
2750 
2751 	return n;
2752 
2753 }
2754 
2755 static int yaffs_GarbageCollectBlock(yaffs_Device * dev, int block)
2756 {
2757 	int oldChunk;
2758 	int newChunk;
2759 	int chunkInBlock;
2760 	int markNAND;
2761 	int retVal = YAFFS_OK;
2762 	int cleanups = 0;
2763 	int i;
2764 	int isCheckpointBlock;
2765 	int matchingChunk;
2766 
2767 	int chunksBefore = yaffs_GetErasedChunks(dev);
2768 	int chunksAfter;
2769 
2770 	yaffs_ExtendedTags tags;
2771 
2772 	yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, block);
2773 
2774 	yaffs_Object *object;
2775 
2776 	isCheckpointBlock = (bi->blockState == YAFFS_BLOCK_STATE_CHECKPOINT);
2777 
2778 	bi->blockState = YAFFS_BLOCK_STATE_COLLECTING;
2779 
2780 	T(YAFFS_TRACE_TRACING,
2781 	  (TSTR("Collecting block %d, in use %d, shrink %d, " TENDSTR), block,
2782 	   bi->pagesInUse, bi->hasShrinkHeader));
2783 
2784 	/*yaffs_VerifyFreeChunks(dev); */
2785 
2786 	bi->hasShrinkHeader = 0;	/* clear the flag so that the block can erase */
2787 
2788 	/* Take off the number of soft deleted entries because
2789 	 * they're going to get really deleted during GC.
2790 	 */
2791 	dev->nFreeChunks -= bi->softDeletions;
2792 
2793 	dev->isDoingGC = 1;
2794 
2795 	if (isCheckpointBlock ||
2796 	    !yaffs_StillSomeChunkBits(dev, block)) {
2797 		T(YAFFS_TRACE_TRACING,
2798 		  (TSTR
2799 		   ("Collecting block %d that has no chunks in use" TENDSTR),
2800 		   block));
2801 		yaffs_BlockBecameDirty(dev, block);
2802 	} else {
2803 
2804 		__u8 *buffer = yaffs_GetTempBuffer(dev, __LINE__);
2805 
2806 		yaffs_VerifyBlock(dev,bi,block);
2807 
2808 		for (chunkInBlock = 0, oldChunk = block * dev->nChunksPerBlock;
2809 		     chunkInBlock < dev->nChunksPerBlock
2810 		     && yaffs_StillSomeChunkBits(dev, block);
2811 		     chunkInBlock++, oldChunk++) {
2812 			if (yaffs_CheckChunkBit(dev, block, chunkInBlock)) {
2813 
2814 				/* This page is in use and might need to be copied off */
2815 
2816 				markNAND = 1;
2817 
2818 				yaffs_InitialiseTags(&tags);
2819 
2820 				yaffs_ReadChunkWithTagsFromNAND(dev, oldChunk,
2821 								buffer, &tags);
2822 
2823 				object =
2824 				    yaffs_FindObjectByNumber(dev,
2825 							     tags.objectId);
2826 
2827 				T(YAFFS_TRACE_GC_DETAIL,
2828 				  (TSTR
2829 				   ("Collecting page %d, %d %d %d " TENDSTR),
2830 				   chunkInBlock, tags.objectId, tags.chunkId,
2831 				   tags.byteCount));
2832 
2833 				if(object && !yaffs_SkipVerification(dev)){
2834 					if(tags.chunkId == 0)
2835 						matchingChunk = object->chunkId;
2836 					else if(object->softDeleted)
2837 						matchingChunk = oldChunk; /* Defeat the test */
2838 					else
2839 						matchingChunk = yaffs_FindChunkInFile(object,tags.chunkId,NULL);
2840 
2841 					if(oldChunk != matchingChunk)
2842 						T(YAFFS_TRACE_ERROR,
2843 						  (TSTR("gc: page in gc mismatch: %d %d %d %d"TENDSTR),
2844 						  oldChunk,matchingChunk,tags.objectId, tags.chunkId));
2845 
2846 				}
2847 
2848 				if (!object) {
2849 					T(YAFFS_TRACE_ERROR,
2850 					  (TSTR
2851 					   ("page %d in gc has no object: %d %d %d "
2852 					    TENDSTR), oldChunk,
2853 					    tags.objectId, tags.chunkId, tags.byteCount));
2854 				}
2855 
2856 				if (object && object->deleted
2857 				    && tags.chunkId != 0) {
2858 					/* Data chunk in a deleted file, throw it away
2859 					 * It's a soft deleted data chunk,
2860 					 * No need to copy this, just forget about it and
2861 					 * fix up the object.
2862 					 */
2863 
2864 					object->nDataChunks--;
2865 
2866 					if (object->nDataChunks <= 0) {
2867 						/* remeber to clean up the object */
2868 						dev->gcCleanupList[cleanups] =
2869 						    tags.objectId;
2870 						cleanups++;
2871 					}
2872 					markNAND = 0;
2873 				} else if (0
2874 					   /* Todo object && object->deleted && object->nDataChunks == 0 */
2875 					   ) {
2876 					/* Deleted object header with no data chunks.
2877 					 * Can be discarded and the file deleted.
2878 					 */
2879 					object->chunkId = 0;
2880 					yaffs_FreeTnode(object->myDev,
2881 							object->variant.
2882 							fileVariant.top);
2883 					object->variant.fileVariant.top = NULL;
2884 					yaffs_DoGenericObjectDeletion(object);
2885 
2886 				} else if (object) {
2887 					/* It's either a data chunk in a live file or
2888 					 * an ObjectHeader, so we're interested in it.
2889 					 * NB Need to keep the ObjectHeaders of deleted files
2890 					 * until the whole file has been deleted off
2891 					 */
2892 					tags.serialNumber++;
2893 
2894 					dev->nGCCopies++;
2895 
2896 					if (tags.chunkId == 0) {
2897 						/* It is an object Id,
2898 						 * We need to nuke the shrinkheader flags first
2899 						 * We no longer want the shrinkHeader flag since its work is done
2900 						 * and if it is left in place it will mess up scanning.
2901 						 * Also, clear out any shadowing stuff
2902 						 */
2903 
2904 						yaffs_ObjectHeader *oh;
2905 						oh = (yaffs_ObjectHeader *)buffer;
2906 						oh->isShrink = 0;
2907 						oh->shadowsObject = -1;
2908 						tags.extraShadows = 0;
2909 						tags.extraIsShrinkHeader = 0;
2910 
2911 						yaffs_VerifyObjectHeader(object,oh,&tags,1);
2912 					}
2913 
2914 					newChunk =
2915 					    yaffs_WriteNewChunkWithTagsToNAND(dev, buffer, &tags, 1);
2916 
2917 					if (newChunk < 0) {
2918 						retVal = YAFFS_FAIL;
2919 					} else {
2920 
2921 						/* Ok, now fix up the Tnodes etc. */
2922 
2923 						if (tags.chunkId == 0) {
2924 							/* It's a header */
2925 							object->chunkId =  newChunk;
2926 							object->serial =   tags.serialNumber;
2927 						} else {
2928 							/* It's a data chunk */
2929 							yaffs_PutChunkIntoFile
2930 							    (object,
2931 							     tags.chunkId,
2932 							     newChunk, 0);
2933 						}
2934 					}
2935 				}
2936 
2937 				yaffs_DeleteChunk(dev, oldChunk, markNAND, __LINE__);
2938 
2939 			}
2940 		}
2941 
2942 		yaffs_ReleaseTempBuffer(dev, buffer, __LINE__);
2943 
2944 
2945 		/* Do any required cleanups */
2946 		for (i = 0; i < cleanups; i++) {
2947 			/* Time to delete the file too */
2948 			object =
2949 			    yaffs_FindObjectByNumber(dev,
2950 						     dev->gcCleanupList[i]);
2951 			if (object) {
2952 				yaffs_FreeTnode(dev,
2953 						object->variant.fileVariant.
2954 						top);
2955 				object->variant.fileVariant.top = NULL;
2956 				T(YAFFS_TRACE_GC,
2957 				  (TSTR
2958 				   ("yaffs: About to finally delete object %d"
2959 				    TENDSTR), object->objectId));
2960 				yaffs_DoGenericObjectDeletion(object);
2961 				object->myDev->nDeletedFiles--;
2962 			}
2963 
2964 		}
2965 
2966 	}
2967 
2968 	yaffs_VerifyCollectedBlock(dev,bi,block);
2969 
2970 	if (chunksBefore >= (chunksAfter = yaffs_GetErasedChunks(dev))) {
2971 		T(YAFFS_TRACE_GC,
2972 		  (TSTR
2973 		   ("gc did not increase free chunks before %d after %d"
2974 		    TENDSTR), chunksBefore, chunksAfter));
2975 	}
2976 
2977 	dev->isDoingGC = 0;
2978 
2979 	return YAFFS_OK;
2980 }
2981 
2982 /* New garbage collector
2983  * If we're very low on erased blocks then we do aggressive garbage collection
2984  * otherwise we do "leasurely" garbage collection.
2985  * Aggressive gc looks further (whole array) and will accept less dirty blocks.
2986  * Passive gc only inspects smaller areas and will only accept more dirty blocks.
2987  *
2988  * The idea is to help clear out space in a more spread-out manner.
2989  * Dunno if it really does anything useful.
2990  */
2991 static int yaffs_CheckGarbageCollection(yaffs_Device * dev)
2992 {
2993 	int block;
2994 	int aggressive;
2995 	int gcOk = YAFFS_OK;
2996 	int maxTries = 0;
2997 
2998 	int checkpointBlockAdjust;
2999 
3000 	if (dev->isDoingGC) {
3001 		/* Bail out so we don't get recursive gc */
3002 		return YAFFS_OK;
3003 	}
3004 
3005 	/* This loop should pass the first time.
3006 	 * We'll only see looping here if the erase of the collected block fails.
3007 	 */
3008 
3009 	do {
3010 		maxTries++;
3011 
3012 		checkpointBlockAdjust = (dev->nCheckpointReservedBlocks - dev->blocksInCheckpoint);
3013 		if(checkpointBlockAdjust < 0)
3014 			checkpointBlockAdjust = 0;
3015 
3016 		if (dev->nErasedBlocks < (dev->nReservedBlocks + checkpointBlockAdjust + 2)) {
3017 			/* We need a block soon...*/
3018 			aggressive = 1;
3019 		} else {
3020 			/* We're in no hurry */
3021 			aggressive = 0;
3022 		}
3023 
3024 		block = yaffs_FindBlockForGarbageCollection(dev, aggressive);
3025 
3026 		if (block > 0) {
3027 			dev->garbageCollections++;
3028 			if (!aggressive) {
3029 				dev->passiveGarbageCollections++;
3030 			}
3031 
3032 			T(YAFFS_TRACE_GC,
3033 			  (TSTR
3034 			   ("yaffs: GC erasedBlocks %d aggressive %d" TENDSTR),
3035 			   dev->nErasedBlocks, aggressive));
3036 
3037 			gcOk = yaffs_GarbageCollectBlock(dev, block);
3038 		}
3039 
3040 		if (dev->nErasedBlocks < (dev->nReservedBlocks) && block > 0) {
3041 			T(YAFFS_TRACE_GC,
3042 			  (TSTR
3043 			   ("yaffs: GC !!!no reclaim!!! erasedBlocks %d after try %d block %d"
3044 			    TENDSTR), dev->nErasedBlocks, maxTries, block));
3045 		}
3046 	} while ((dev->nErasedBlocks < dev->nReservedBlocks) && (block > 0)
3047 		 && (maxTries < 2));
3048 
3049 	return aggressive ? gcOk : YAFFS_OK;
3050 }
3051 
3052 /*-------------------------  TAGS --------------------------------*/
3053 
3054 static int yaffs_TagsMatch(const yaffs_ExtendedTags * tags, int objectId,
3055 			   int chunkInObject)
3056 {
3057 	return (tags->chunkId == chunkInObject &&
3058 		tags->objectId == objectId && !tags->chunkDeleted) ? 1 : 0;
3059 
3060 }
3061 
3062 
3063 /*-------------------- Data file manipulation -----------------*/
3064 
3065 static int yaffs_FindChunkInFile(yaffs_Object * in, int chunkInInode,
3066 				 yaffs_ExtendedTags * tags)
3067 {
3068 	/*Get the Tnode, then get the level 0 offset chunk offset */
3069 	yaffs_Tnode *tn;
3070 	int theChunk = -1;
3071 	yaffs_ExtendedTags localTags;
3072 	int retVal = -1;
3073 
3074 	yaffs_Device *dev = in->myDev;
3075 
3076 	if (!tags) {
3077 		/* Passed a NULL, so use our own tags space */
3078 		tags = &localTags;
3079 	}
3080 
3081 	tn = yaffs_FindLevel0Tnode(dev, &in->variant.fileVariant, chunkInInode);
3082 
3083 	if (tn) {
3084 		theChunk = yaffs_GetChunkGroupBase(dev,tn,chunkInInode);
3085 
3086 		retVal =
3087 		    yaffs_FindChunkInGroup(dev, theChunk, tags, in->objectId,
3088 					   chunkInInode);
3089 	}
3090 	return retVal;
3091 }
3092 
3093 static int yaffs_FindAndDeleteChunkInFile(yaffs_Object * in, int chunkInInode,
3094 					  yaffs_ExtendedTags * tags)
3095 {
3096 	/* Get the Tnode, then get the level 0 offset chunk offset */
3097 	yaffs_Tnode *tn;
3098 	int theChunk = -1;
3099 	yaffs_ExtendedTags localTags;
3100 
3101 	yaffs_Device *dev = in->myDev;
3102 	int retVal = -1;
3103 
3104 	if (!tags) {
3105 		/* Passed a NULL, so use our own tags space */
3106 		tags = &localTags;
3107 	}
3108 
3109 	tn = yaffs_FindLevel0Tnode(dev, &in->variant.fileVariant, chunkInInode);
3110 
3111 	if (tn) {
3112 
3113 		theChunk = yaffs_GetChunkGroupBase(dev,tn,chunkInInode);
3114 
3115 		retVal =
3116 		    yaffs_FindChunkInGroup(dev, theChunk, tags, in->objectId,
3117 					   chunkInInode);
3118 
3119 		/* Delete the entry in the filestructure (if found) */
3120 		if (retVal != -1) {
3121 			yaffs_PutLevel0Tnode(dev,tn,chunkInInode,0);
3122 		}
3123 	} else {
3124 		/*T(("No level 0 found for %d\n", chunkInInode)); */
3125 	}
3126 
3127 	if (retVal == -1) {
3128 		/* T(("Could not find %d to delete\n",chunkInInode)); */
3129 	}
3130 	return retVal;
3131 }
3132 
3133 #ifdef YAFFS_PARANOID
3134 
3135 static int yaffs_CheckFileSanity(yaffs_Object * in)
3136 {
3137 	int chunk;
3138 	int nChunks;
3139 	int fSize;
3140 	int failed = 0;
3141 	int objId;
3142 	yaffs_Tnode *tn;
3143 	yaffs_Tags localTags;
3144 	yaffs_Tags *tags = &localTags;
3145 	int theChunk;
3146 	int chunkDeleted;
3147 
3148 	if (in->variantType != YAFFS_OBJECT_TYPE_FILE) {
3149 		/* T(("Object not a file\n")); */
3150 		return YAFFS_FAIL;
3151 	}
3152 
3153 	objId = in->objectId;
3154 	fSize = in->variant.fileVariant.fileSize;
3155 	nChunks =
3156 	    (fSize + in->myDev->nDataBytesPerChunk - 1) / in->myDev->nDataBytesPerChunk;
3157 
3158 	for (chunk = 1; chunk <= nChunks; chunk++) {
3159 		tn = yaffs_FindLevel0Tnode(in->myDev, &in->variant.fileVariant,
3160 					   chunk);
3161 
3162 		if (tn) {
3163 
3164 			theChunk = yaffs_GetChunkGroupBase(dev,tn,chunk);
3165 
3166 			if (yaffs_CheckChunkBits
3167 			    (dev, theChunk / dev->nChunksPerBlock,
3168 			     theChunk % dev->nChunksPerBlock)) {
3169 
3170 				yaffs_ReadChunkTagsFromNAND(in->myDev, theChunk,
3171 							    tags,
3172 							    &chunkDeleted);
3173 				if (yaffs_TagsMatch
3174 				    (tags, in->objectId, chunk, chunkDeleted)) {
3175 					/* found it; */
3176 
3177 				}
3178 			} else {
3179 
3180 				failed = 1;
3181 			}
3182 
3183 		} else {
3184 			/* T(("No level 0 found for %d\n", chunk)); */
3185 		}
3186 	}
3187 
3188 	return failed ? YAFFS_FAIL : YAFFS_OK;
3189 }
3190 
3191 #endif
3192 
3193 static int yaffs_PutChunkIntoFile(yaffs_Object * in, int chunkInInode,
3194 				  int chunkInNAND, int inScan)
3195 {
3196 	/* NB inScan is zero unless scanning.
3197 	 * For forward scanning, inScan is > 0;
3198 	 * for backward scanning inScan is < 0
3199 	 */
3200 
3201 	yaffs_Tnode *tn;
3202 	yaffs_Device *dev = in->myDev;
3203 	int existingChunk;
3204 	yaffs_ExtendedTags existingTags;
3205 	yaffs_ExtendedTags newTags;
3206 	unsigned existingSerial, newSerial;
3207 
3208 	if (in->variantType != YAFFS_OBJECT_TYPE_FILE) {
3209 		/* Just ignore an attempt at putting a chunk into a non-file during scanning
3210 		 * If it is not during Scanning then something went wrong!
3211 		 */
3212 		if (!inScan) {
3213 			T(YAFFS_TRACE_ERROR,
3214 			  (TSTR
3215 			   ("yaffs tragedy:attempt to put data chunk into a non-file"
3216 			    TENDSTR)));
3217 			YBUG();
3218 		}
3219 
3220 		yaffs_DeleteChunk(dev, chunkInNAND, 1, __LINE__);
3221 		return YAFFS_OK;
3222 	}
3223 
3224 	tn = yaffs_AddOrFindLevel0Tnode(dev,
3225 					&in->variant.fileVariant,
3226 					chunkInInode,
3227 					NULL);
3228 	if (!tn) {
3229 		return YAFFS_FAIL;
3230 	}
3231 
3232 	existingChunk = yaffs_GetChunkGroupBase(dev,tn,chunkInInode);
3233 
3234 	if (inScan != 0) {
3235 		/* If we're scanning then we need to test for duplicates
3236 		 * NB This does not need to be efficient since it should only ever
3237 		 * happen when the power fails during a write, then only one
3238 		 * chunk should ever be affected.
3239 		 *
3240 		 * Correction for YAFFS2: This could happen quite a lot and we need to think about efficiency! TODO
3241 		 * Update: For backward scanning we don't need to re-read tags so this is quite cheap.
3242 		 */
3243 
3244 		if (existingChunk != 0) {
3245 			/* NB Right now existing chunk will not be real chunkId if the device >= 32MB
3246 			 *    thus we have to do a FindChunkInFile to get the real chunk id.
3247 			 *
3248 			 * We have a duplicate now we need to decide which one to use:
3249 			 *
3250 			 * Backwards scanning YAFFS2: The old one is what we use, dump the new one.
3251 			 * Forward scanning YAFFS2: The new one is what we use, dump the old one.
3252 			 * YAFFS1: Get both sets of tags and compare serial numbers.
3253 			 */
3254 
3255 			if (inScan > 0) {
3256 				/* Only do this for forward scanning */
3257 				yaffs_ReadChunkWithTagsFromNAND(dev,
3258 								chunkInNAND,
3259 								NULL, &newTags);
3260 
3261 				/* Do a proper find */
3262 				existingChunk =
3263 				    yaffs_FindChunkInFile(in, chunkInInode,
3264 							  &existingTags);
3265 			}
3266 
3267 			if (existingChunk <= 0) {
3268 				/*Hoosterman - how did this happen? */
3269 
3270 				T(YAFFS_TRACE_ERROR,
3271 				  (TSTR
3272 				   ("yaffs tragedy: existing chunk < 0 in scan"
3273 				    TENDSTR)));
3274 
3275 			}
3276 
3277 			/* NB The deleted flags should be false, otherwise the chunks will
3278 			 * not be loaded during a scan
3279 			 */
3280 
3281 			newSerial = newTags.serialNumber;
3282 			existingSerial = existingTags.serialNumber;
3283 
3284 			if ((inScan > 0) &&
3285 			    (in->myDev->isYaffs2 ||
3286 			     existingChunk <= 0 ||
3287 			     ((existingSerial + 1) & 3) == newSerial)) {
3288 				/* Forward scanning.
3289 				 * Use new
3290 				 * Delete the old one and drop through to update the tnode
3291 				 */
3292 				yaffs_DeleteChunk(dev, existingChunk, 1,
3293 						  __LINE__);
3294 			} else {
3295 				/* Backward scanning or we want to use the existing one
3296 				 * Use existing.
3297 				 * Delete the new one and return early so that the tnode isn't changed
3298 				 */
3299 				yaffs_DeleteChunk(dev, chunkInNAND, 1,
3300 						  __LINE__);
3301 				return YAFFS_OK;
3302 			}
3303 		}
3304 
3305 	}
3306 
3307 	if (existingChunk == 0) {
3308 		in->nDataChunks++;
3309 	}
3310 
3311 	yaffs_PutLevel0Tnode(dev,tn,chunkInInode,chunkInNAND);
3312 
3313 	return YAFFS_OK;
3314 }
3315 
3316 static int yaffs_ReadChunkDataFromObject(yaffs_Object * in, int chunkInInode,
3317 					 __u8 * buffer)
3318 {
3319 	int chunkInNAND = yaffs_FindChunkInFile(in, chunkInInode, NULL);
3320 
3321 	if (chunkInNAND >= 0) {
3322 		return yaffs_ReadChunkWithTagsFromNAND(in->myDev, chunkInNAND,
3323 						       buffer,NULL);
3324 	} else {
3325 		T(YAFFS_TRACE_NANDACCESS,
3326 		  (TSTR("Chunk %d not found zero instead" TENDSTR),
3327 		   chunkInNAND));
3328 		/* get sane (zero) data if you read a hole */
3329 		memset(buffer, 0, in->myDev->nDataBytesPerChunk);
3330 		return 0;
3331 	}
3332 
3333 }
3334 
3335 void yaffs_DeleteChunk(yaffs_Device * dev, int chunkId, int markNAND, int lyn)
3336 {
3337 	int block;
3338 	int page;
3339 	yaffs_ExtendedTags tags;
3340 	yaffs_BlockInfo *bi;
3341 
3342 	if (chunkId <= 0)
3343 		return;
3344 
3345 
3346 	dev->nDeletions++;
3347 	block = chunkId / dev->nChunksPerBlock;
3348 	page = chunkId % dev->nChunksPerBlock;
3349 
3350 
3351 	if(!yaffs_CheckChunkBit(dev,block,page))
3352 		T(YAFFS_TRACE_VERIFY,
3353 			(TSTR("Deleting invalid chunk %d"TENDSTR),
3354 			 chunkId));
3355 
3356 	bi = yaffs_GetBlockInfo(dev, block);
3357 
3358 	T(YAFFS_TRACE_DELETION,
3359 	  (TSTR("line %d delete of chunk %d" TENDSTR), lyn, chunkId));
3360 
3361 	if (markNAND &&
3362 	    bi->blockState != YAFFS_BLOCK_STATE_COLLECTING && !dev->isYaffs2) {
3363 
3364 		yaffs_InitialiseTags(&tags);
3365 
3366 		tags.chunkDeleted = 1;
3367 
3368 		yaffs_WriteChunkWithTagsToNAND(dev, chunkId, NULL, &tags);
3369 		yaffs_HandleUpdateChunk(dev, chunkId, &tags);
3370 	} else {
3371 		dev->nUnmarkedDeletions++;
3372 	}
3373 
3374 	/* Pull out of the management area.
3375 	 * If the whole block became dirty, this will kick off an erasure.
3376 	 */
3377 	if (bi->blockState == YAFFS_BLOCK_STATE_ALLOCATING ||
3378 	    bi->blockState == YAFFS_BLOCK_STATE_FULL ||
3379 	    bi->blockState == YAFFS_BLOCK_STATE_NEEDS_SCANNING ||
3380 	    bi->blockState == YAFFS_BLOCK_STATE_COLLECTING) {
3381 		dev->nFreeChunks++;
3382 
3383 		yaffs_ClearChunkBit(dev, block, page);
3384 
3385 		bi->pagesInUse--;
3386 
3387 		if (bi->pagesInUse == 0 &&
3388 		    !bi->hasShrinkHeader &&
3389 		    bi->blockState != YAFFS_BLOCK_STATE_ALLOCATING &&
3390 		    bi->blockState != YAFFS_BLOCK_STATE_NEEDS_SCANNING) {
3391 			yaffs_BlockBecameDirty(dev, block);
3392 		}
3393 
3394 	} else {
3395 		/* T(("Bad news deleting chunk %d\n",chunkId)); */
3396 	}
3397 
3398 }
3399 
3400 static int yaffs_WriteChunkDataToObject(yaffs_Object * in, int chunkInInode,
3401 					const __u8 * buffer, int nBytes,
3402 					int useReserve)
3403 {
3404 	/* Find old chunk Need to do this to get serial number
3405 	 * Write new one and patch into tree.
3406 	 * Invalidate old tags.
3407 	 */
3408 
3409 	int prevChunkId;
3410 	yaffs_ExtendedTags prevTags;
3411 
3412 	int newChunkId;
3413 	yaffs_ExtendedTags newTags;
3414 
3415 	yaffs_Device *dev = in->myDev;
3416 
3417 	yaffs_CheckGarbageCollection(dev);
3418 
3419 	/* Get the previous chunk at this location in the file if it exists */
3420 	prevChunkId = yaffs_FindChunkInFile(in, chunkInInode, &prevTags);
3421 
3422 	/* Set up new tags */
3423 	yaffs_InitialiseTags(&newTags);
3424 
3425 	newTags.chunkId = chunkInInode;
3426 	newTags.objectId = in->objectId;
3427 	newTags.serialNumber =
3428 	    (prevChunkId >= 0) ? prevTags.serialNumber + 1 : 1;
3429 	newTags.byteCount = nBytes;
3430 
3431 	newChunkId =
3432 	    yaffs_WriteNewChunkWithTagsToNAND(dev, buffer, &newTags,
3433 					      useReserve);
3434 
3435 	if (newChunkId >= 0) {
3436 		yaffs_PutChunkIntoFile(in, chunkInInode, newChunkId, 0);
3437 
3438 		if (prevChunkId >= 0) {
3439 			yaffs_DeleteChunk(dev, prevChunkId, 1, __LINE__);
3440 
3441 		}
3442 
3443 		yaffs_CheckFileSanity(in);
3444 	}
3445 	return newChunkId;
3446 
3447 }
3448 
3449 /* UpdateObjectHeader updates the header on NAND for an object.
3450  * If name is not NULL, then that new name is used.
3451  */
3452 int yaffs_UpdateObjectHeader(yaffs_Object * in, const YCHAR * name, int force,
3453 			     int isShrink, int shadows)
3454 {
3455 
3456 	yaffs_BlockInfo *bi;
3457 
3458 	yaffs_Device *dev = in->myDev;
3459 
3460 	int prevChunkId;
3461 	int retVal = 0;
3462 
3463 	int newChunkId;
3464 	yaffs_ExtendedTags newTags;
3465 	yaffs_ExtendedTags oldTags;
3466 
3467 	__u8 *buffer = NULL;
3468 	YCHAR oldName[YAFFS_MAX_NAME_LENGTH + 1];
3469 
3470 	yaffs_ObjectHeader *oh = NULL;
3471 
3472 	yaffs_strcpy(oldName,"silly old name");
3473 
3474 	if (!in->fake || force) {
3475 
3476 		yaffs_CheckGarbageCollection(dev);
3477 		yaffs_CheckObjectDetailsLoaded(in);
3478 
3479 		buffer = yaffs_GetTempBuffer(in->myDev, __LINE__);
3480 		oh = (yaffs_ObjectHeader *) buffer;
3481 
3482 		prevChunkId = in->chunkId;
3483 
3484 		if (prevChunkId >= 0) {
3485 			yaffs_ReadChunkWithTagsFromNAND(dev, prevChunkId,
3486 							buffer, &oldTags);
3487 
3488 			yaffs_VerifyObjectHeader(in,oh,&oldTags,0);
3489 
3490 			memcpy(oldName, oh->name, sizeof(oh->name));
3491 		}
3492 
3493 		memset(buffer, 0xFF, dev->nDataBytesPerChunk);
3494 
3495 		oh->type = in->variantType;
3496 		oh->yst_mode = in->yst_mode;
3497 		oh->shadowsObject = shadows;
3498 
3499 #ifdef CONFIG_YAFFS_WINCE
3500 		oh->win_atime[0] = in->win_atime[0];
3501 		oh->win_ctime[0] = in->win_ctime[0];
3502 		oh->win_mtime[0] = in->win_mtime[0];
3503 		oh->win_atime[1] = in->win_atime[1];
3504 		oh->win_ctime[1] = in->win_ctime[1];
3505 		oh->win_mtime[1] = in->win_mtime[1];
3506 #else
3507 		oh->yst_uid = in->yst_uid;
3508 		oh->yst_gid = in->yst_gid;
3509 		oh->yst_atime = in->yst_atime;
3510 		oh->yst_mtime = in->yst_mtime;
3511 		oh->yst_ctime = in->yst_ctime;
3512 		oh->yst_rdev = in->yst_rdev;
3513 #endif
3514 		if (in->parent) {
3515 			oh->parentObjectId = in->parent->objectId;
3516 		} else {
3517 			oh->parentObjectId = 0;
3518 		}
3519 
3520 		if (name && *name) {
3521 			memset(oh->name, 0, sizeof(oh->name));
3522 			yaffs_strncpy(oh->name, name, YAFFS_MAX_NAME_LENGTH);
3523 		} else if (prevChunkId>=0) {
3524 			memcpy(oh->name, oldName, sizeof(oh->name));
3525 		} else {
3526 			memset(oh->name, 0, sizeof(oh->name));
3527 		}
3528 
3529 		oh->isShrink = isShrink;
3530 
3531 		switch (in->variantType) {
3532 		case YAFFS_OBJECT_TYPE_UNKNOWN:
3533 			/* Should not happen */
3534 			break;
3535 		case YAFFS_OBJECT_TYPE_FILE:
3536 			oh->fileSize =
3537 			    (oh->parentObjectId == YAFFS_OBJECTID_DELETED
3538 			     || oh->parentObjectId ==
3539 			     YAFFS_OBJECTID_UNLINKED) ? 0 : in->variant.
3540 			    fileVariant.fileSize;
3541 			break;
3542 		case YAFFS_OBJECT_TYPE_HARDLINK:
3543 			oh->equivalentObjectId =
3544 			    in->variant.hardLinkVariant.equivalentObjectId;
3545 			break;
3546 		case YAFFS_OBJECT_TYPE_SPECIAL:
3547 			/* Do nothing */
3548 			break;
3549 		case YAFFS_OBJECT_TYPE_DIRECTORY:
3550 			/* Do nothing */
3551 			break;
3552 		case YAFFS_OBJECT_TYPE_SYMLINK:
3553 			yaffs_strncpy(oh->alias,
3554 				      in->variant.symLinkVariant.alias,
3555 				      YAFFS_MAX_ALIAS_LENGTH);
3556 			oh->alias[YAFFS_MAX_ALIAS_LENGTH] = 0;
3557 			break;
3558 		}
3559 
3560 		/* Tags */
3561 		yaffs_InitialiseTags(&newTags);
3562 		in->serial++;
3563 		newTags.chunkId = 0;
3564 		newTags.objectId = in->objectId;
3565 		newTags.serialNumber = in->serial;
3566 
3567 		/* Add extra info for file header */
3568 
3569 		newTags.extraHeaderInfoAvailable = 1;
3570 		newTags.extraParentObjectId = oh->parentObjectId;
3571 		newTags.extraFileLength = oh->fileSize;
3572 		newTags.extraIsShrinkHeader = oh->isShrink;
3573 		newTags.extraEquivalentObjectId = oh->equivalentObjectId;
3574 		newTags.extraShadows = (oh->shadowsObject > 0) ? 1 : 0;
3575 		newTags.extraObjectType = in->variantType;
3576 
3577 		yaffs_VerifyObjectHeader(in,oh,&newTags,1);
3578 
3579 		/* Create new chunk in NAND */
3580 		newChunkId =
3581 		    yaffs_WriteNewChunkWithTagsToNAND(dev, buffer, &newTags,
3582 						      (prevChunkId >= 0) ? 1 : 0);
3583 
3584 		if (newChunkId >= 0) {
3585 
3586 			in->chunkId = newChunkId;
3587 
3588 			if (prevChunkId >= 0) {
3589 				yaffs_DeleteChunk(dev, prevChunkId, 1,
3590 						  __LINE__);
3591 			}
3592 
3593 			if(!yaffs_ObjectHasCachedWriteData(in))
3594 				in->dirty = 0;
3595 
3596 			/* If this was a shrink, then mark the block that the chunk lives on */
3597 			if (isShrink) {
3598 				bi = yaffs_GetBlockInfo(in->myDev,
3599 							newChunkId /in->myDev->	nChunksPerBlock);
3600 				bi->hasShrinkHeader = 1;
3601 			}
3602 
3603 		}
3604 
3605 		retVal = newChunkId;
3606 
3607 	}
3608 
3609 	if (buffer)
3610 		yaffs_ReleaseTempBuffer(dev, buffer, __LINE__);
3611 
3612 	return retVal;
3613 }
3614 
3615 /*------------------------ Short Operations Cache ----------------------------------------
3616  *   In many situations where there is no high level buffering (eg WinCE) a lot of
3617  *   reads might be short sequential reads, and a lot of writes may be short
3618  *   sequential writes. eg. scanning/writing a jpeg file.
3619  *   In these cases, a short read/write cache can provide a huge perfomance benefit
3620  *   with dumb-as-a-rock code.
3621  *   In Linux, the page cache provides read buffering aand the short op cache provides write
3622  *   buffering.
3623  *
3624  *   There are a limited number (~10) of cache chunks per device so that we don't
3625  *   need a very intelligent search.
3626  */
3627 
3628 static int yaffs_ObjectHasCachedWriteData(yaffs_Object *obj)
3629 {
3630 	yaffs_Device *dev = obj->myDev;
3631 	int i;
3632 	yaffs_ChunkCache *cache;
3633 	int nCaches = obj->myDev->nShortOpCaches;
3634 
3635 	for(i = 0; i < nCaches; i++){
3636 		cache = &dev->srCache[i];
3637 		if (cache->object == obj &&
3638 		    cache->dirty)
3639 			return 1;
3640 	}
3641 
3642 	return 0;
3643 }
3644 
3645 
3646 static void yaffs_FlushFilesChunkCache(yaffs_Object * obj)
3647 {
3648 	yaffs_Device *dev = obj->myDev;
3649 	int lowest = -99;	/* Stop compiler whining. */
3650 	int i;
3651 	yaffs_ChunkCache *cache;
3652 	int chunkWritten = 0;
3653 	int nCaches = obj->myDev->nShortOpCaches;
3654 
3655 	if (nCaches > 0) {
3656 		do {
3657 			cache = NULL;
3658 
3659 			/* Find the dirty cache for this object with the lowest chunk id. */
3660 			for (i = 0; i < nCaches; i++) {
3661 				if (dev->srCache[i].object == obj &&
3662 				    dev->srCache[i].dirty) {
3663 					if (!cache
3664 					    || dev->srCache[i].chunkId <
3665 					    lowest) {
3666 						cache = &dev->srCache[i];
3667 						lowest = cache->chunkId;
3668 					}
3669 				}
3670 			}
3671 
3672 			if (cache && !cache->locked) {
3673 				/* Write it out and free it up */
3674 
3675 				chunkWritten =
3676 				    yaffs_WriteChunkDataToObject(cache->object,
3677 								 cache->chunkId,
3678 								 cache->data,
3679 								 cache->nBytes,
3680 								 1);
3681 				cache->dirty = 0;
3682 				cache->object = NULL;
3683 			}
3684 
3685 		} while (cache && chunkWritten > 0);
3686 
3687 		if (cache) {
3688 			/* Hoosterman, disk full while writing cache out. */
3689 			T(YAFFS_TRACE_ERROR,
3690 			  (TSTR("yaffs tragedy: no space during cache write" TENDSTR)));
3691 
3692 		}
3693 	}
3694 
3695 }
3696 
3697 /*yaffs_FlushEntireDeviceCache(dev)
3698  *
3699  *
3700  */
3701 
3702 void yaffs_FlushEntireDeviceCache(yaffs_Device *dev)
3703 {
3704 	yaffs_Object *obj;
3705 	int nCaches = dev->nShortOpCaches;
3706 	int i;
3707 
3708 	/* Find a dirty object in the cache and flush it...
3709 	 * until there are no further dirty objects.
3710 	 */
3711 	do {
3712 		obj = NULL;
3713 		for( i = 0; i < nCaches && !obj; i++) {
3714 			if (dev->srCache[i].object &&
3715 			    dev->srCache[i].dirty)
3716 				obj = dev->srCache[i].object;
3717 
3718 		}
3719 		if(obj)
3720 			yaffs_FlushFilesChunkCache(obj);
3721 
3722 	} while(obj);
3723 
3724 }
3725 
3726 
3727 /* Grab us a cache chunk for use.
3728  * First look for an empty one.
3729  * Then look for the least recently used non-dirty one.
3730  * Then look for the least recently used dirty one...., flush and look again.
3731  */
3732 static yaffs_ChunkCache *yaffs_GrabChunkCacheWorker(yaffs_Device * dev)
3733 {
3734 	int i;
3735 	int usage;
3736 	int theOne;
3737 
3738 	if (dev->nShortOpCaches > 0) {
3739 		for (i = 0; i < dev->nShortOpCaches; i++) {
3740 			if (!dev->srCache[i].object)
3741 				return &dev->srCache[i];
3742 		}
3743 
3744 		return NULL;
3745 
3746 		theOne = -1;
3747 		usage = 0;	/* just to stop the compiler grizzling */
3748 
3749 		for (i = 0; i < dev->nShortOpCaches; i++) {
3750 			if (!dev->srCache[i].dirty &&
3751 			    ((dev->srCache[i].lastUse < usage && theOne >= 0) ||
3752 			     theOne < 0)) {
3753 				usage = dev->srCache[i].lastUse;
3754 				theOne = i;
3755 			}
3756 		}
3757 
3758 
3759 		return theOne >= 0 ? &dev->srCache[theOne] : NULL;
3760 	} else {
3761 		return NULL;
3762 	}
3763 
3764 }
3765 
3766 static yaffs_ChunkCache *yaffs_GrabChunkCache(yaffs_Device * dev)
3767 {
3768 	yaffs_ChunkCache *cache;
3769 	yaffs_Object *theObj;
3770 	int usage;
3771 	int i;
3772 
3773 	if (dev->nShortOpCaches > 0) {
3774 		/* Try find a non-dirty one... */
3775 
3776 		cache = yaffs_GrabChunkCacheWorker(dev);
3777 
3778 		if (!cache) {
3779 			/* They were all dirty, find the last recently used object and flush
3780 			 * its cache, then  find again.
3781 			 * NB what's here is not very accurate, we actually flush the object
3782 			 * the last recently used page.
3783 			 */
3784 
3785 			/* With locking we can't assume we can use entry zero */
3786 
3787 			theObj = NULL;
3788 			usage = -1;
3789 			cache = NULL;
3790 
3791 			for (i = 0; i < dev->nShortOpCaches; i++) {
3792 				if (dev->srCache[i].object &&
3793 				    !dev->srCache[i].locked &&
3794 				    (dev->srCache[i].lastUse < usage || !cache))
3795 				{
3796 					usage = dev->srCache[i].lastUse;
3797 					theObj = dev->srCache[i].object;
3798 					cache = &dev->srCache[i];
3799 				}
3800 			}
3801 
3802 			if (!cache || cache->dirty) {
3803 				/* Flush and try again */
3804 				yaffs_FlushFilesChunkCache(theObj);
3805 				cache = yaffs_GrabChunkCacheWorker(dev);
3806 			}
3807 
3808 		}
3809 		return cache;
3810 	} else
3811 		return NULL;
3812 
3813 }
3814 
3815 /* Find a cached chunk */
3816 static yaffs_ChunkCache *yaffs_FindChunkCache(const yaffs_Object * obj,
3817 					      int chunkId)
3818 {
3819 	yaffs_Device *dev = obj->myDev;
3820 	int i;
3821 	if (dev->nShortOpCaches > 0) {
3822 		for (i = 0; i < dev->nShortOpCaches; i++) {
3823 			if (dev->srCache[i].object == obj &&
3824 			    dev->srCache[i].chunkId == chunkId) {
3825 				dev->cacheHits++;
3826 
3827 				return &dev->srCache[i];
3828 			}
3829 		}
3830 	}
3831 	return NULL;
3832 }
3833 
3834 /* Mark the chunk for the least recently used algorithym */
3835 static void yaffs_UseChunkCache(yaffs_Device * dev, yaffs_ChunkCache * cache,
3836 				int isAWrite)
3837 {
3838 
3839 	if (dev->nShortOpCaches > 0) {
3840 		if (dev->srLastUse < 0 || dev->srLastUse > 100000000) {
3841 			/* Reset the cache usages */
3842 			int i;
3843 			for (i = 1; i < dev->nShortOpCaches; i++) {
3844 				dev->srCache[i].lastUse = 0;
3845 			}
3846 			dev->srLastUse = 0;
3847 		}
3848 
3849 		dev->srLastUse++;
3850 
3851 		cache->lastUse = dev->srLastUse;
3852 
3853 		if (isAWrite) {
3854 			cache->dirty = 1;
3855 		}
3856 	}
3857 }
3858 
3859 /* Invalidate a single cache page.
3860  * Do this when a whole page gets written,
3861  * ie the short cache for this page is no longer valid.
3862  */
3863 static void yaffs_InvalidateChunkCache(yaffs_Object * object, int chunkId)
3864 {
3865 	if (object->myDev->nShortOpCaches > 0) {
3866 		yaffs_ChunkCache *cache = yaffs_FindChunkCache(object, chunkId);
3867 
3868 		if (cache) {
3869 			cache->object = NULL;
3870 		}
3871 	}
3872 }
3873 
3874 /* Invalidate all the cache pages associated with this object
3875  * Do this whenever ther file is deleted or resized.
3876  */
3877 static void yaffs_InvalidateWholeChunkCache(yaffs_Object * in)
3878 {
3879 	int i;
3880 	yaffs_Device *dev = in->myDev;
3881 
3882 	if (dev->nShortOpCaches > 0) {
3883 		/* Invalidate it. */
3884 		for (i = 0; i < dev->nShortOpCaches; i++) {
3885 			if (dev->srCache[i].object == in) {
3886 				dev->srCache[i].object = NULL;
3887 			}
3888 		}
3889 	}
3890 }
3891 
3892 /*--------------------- Checkpointing --------------------*/
3893 
3894 
3895 static int yaffs_WriteCheckpointValidityMarker(yaffs_Device *dev,int head)
3896 {
3897 	yaffs_CheckpointValidity cp;
3898 
3899 	memset(&cp,0,sizeof(cp));
3900 
3901 	cp.structType = sizeof(cp);
3902 	cp.magic = YAFFS_MAGIC;
3903 	cp.version = YAFFS_CHECKPOINT_VERSION;
3904 	cp.head = (head) ? 1 : 0;
3905 
3906 	return (yaffs_CheckpointWrite(dev,&cp,sizeof(cp)) == sizeof(cp))?
3907 		1 : 0;
3908 }
3909 
3910 static int yaffs_ReadCheckpointValidityMarker(yaffs_Device *dev, int head)
3911 {
3912 	yaffs_CheckpointValidity cp;
3913 	int ok;
3914 
3915 	ok = (yaffs_CheckpointRead(dev,&cp,sizeof(cp)) == sizeof(cp));
3916 
3917 	if(ok)
3918 		ok = (cp.structType == sizeof(cp)) &&
3919 		     (cp.magic == YAFFS_MAGIC) &&
3920 		     (cp.version == YAFFS_CHECKPOINT_VERSION) &&
3921 		     (cp.head == ((head) ? 1 : 0));
3922 	return ok ? 1 : 0;
3923 }
3924 
3925 static void yaffs_DeviceToCheckpointDevice(yaffs_CheckpointDevice *cp,
3926 					   yaffs_Device *dev)
3927 {
3928 	cp->nErasedBlocks = dev->nErasedBlocks;
3929 	cp->allocationBlock = dev->allocationBlock;
3930 	cp->allocationPage = dev->allocationPage;
3931 	cp->nFreeChunks = dev->nFreeChunks;
3932 
3933 	cp->nDeletedFiles = dev->nDeletedFiles;
3934 	cp->nUnlinkedFiles = dev->nUnlinkedFiles;
3935 	cp->nBackgroundDeletions = dev->nBackgroundDeletions;
3936 	cp->sequenceNumber = dev->sequenceNumber;
3937 	cp->oldestDirtySequence = dev->oldestDirtySequence;
3938 
3939 }
3940 
3941 static void yaffs_CheckpointDeviceToDevice(yaffs_Device *dev,
3942 					   yaffs_CheckpointDevice *cp)
3943 {
3944 	dev->nErasedBlocks = cp->nErasedBlocks;
3945 	dev->allocationBlock = cp->allocationBlock;
3946 	dev->allocationPage = cp->allocationPage;
3947 	dev->nFreeChunks = cp->nFreeChunks;
3948 
3949 	dev->nDeletedFiles = cp->nDeletedFiles;
3950 	dev->nUnlinkedFiles = cp->nUnlinkedFiles;
3951 	dev->nBackgroundDeletions = cp->nBackgroundDeletions;
3952 	dev->sequenceNumber = cp->sequenceNumber;
3953 	dev->oldestDirtySequence = cp->oldestDirtySequence;
3954 }
3955 
3956 
3957 static int yaffs_WriteCheckpointDevice(yaffs_Device *dev)
3958 {
3959 	yaffs_CheckpointDevice cp;
3960 	__u32 nBytes;
3961 	__u32 nBlocks = (dev->internalEndBlock - dev->internalStartBlock + 1);
3962 
3963 	int ok;
3964 
3965 	/* Write device runtime values*/
3966 	yaffs_DeviceToCheckpointDevice(&cp,dev);
3967 	cp.structType = sizeof(cp);
3968 
3969 	ok = (yaffs_CheckpointWrite(dev,&cp,sizeof(cp)) == sizeof(cp));
3970 
3971 	/* Write block info */
3972 	if(ok) {
3973 		nBytes = nBlocks * sizeof(yaffs_BlockInfo);
3974 		ok = (yaffs_CheckpointWrite(dev,dev->blockInfo,nBytes) == nBytes);
3975 	}
3976 
3977 	/* Write chunk bits */
3978 	if(ok) {
3979 		nBytes = nBlocks * dev->chunkBitmapStride;
3980 		ok = (yaffs_CheckpointWrite(dev,dev->chunkBits,nBytes) == nBytes);
3981 	}
3982 	return	 ok ? 1 : 0;
3983 
3984 }
3985 
3986 static int yaffs_ReadCheckpointDevice(yaffs_Device *dev)
3987 {
3988 	yaffs_CheckpointDevice cp;
3989 	__u32 nBytes;
3990 	__u32 nBlocks = (dev->internalEndBlock - dev->internalStartBlock + 1);
3991 
3992 	int ok;
3993 
3994 	ok = (yaffs_CheckpointRead(dev,&cp,sizeof(cp)) == sizeof(cp));
3995 	if(!ok)
3996 		return 0;
3997 
3998 	if(cp.structType != sizeof(cp))
3999 		return 0;
4000 
4001 
4002 	yaffs_CheckpointDeviceToDevice(dev,&cp);
4003 
4004 	nBytes = nBlocks * sizeof(yaffs_BlockInfo);
4005 
4006 	ok = (yaffs_CheckpointRead(dev,dev->blockInfo,nBytes) == nBytes);
4007 
4008 	if(!ok)
4009 		return 0;
4010 	nBytes = nBlocks * dev->chunkBitmapStride;
4011 
4012 	ok = (yaffs_CheckpointRead(dev,dev->chunkBits,nBytes) == nBytes);
4013 
4014 	return ok ? 1 : 0;
4015 }
4016 
4017 static void yaffs_ObjectToCheckpointObject(yaffs_CheckpointObject *cp,
4018 					   yaffs_Object *obj)
4019 {
4020 
4021 	cp->objectId = obj->objectId;
4022 	cp->parentId = (obj->parent) ? obj->parent->objectId : 0;
4023 	cp->chunkId = obj->chunkId;
4024 	cp->variantType = obj->variantType;
4025 	cp->deleted = obj->deleted;
4026 	cp->softDeleted = obj->softDeleted;
4027 	cp->unlinked = obj->unlinked;
4028 	cp->fake = obj->fake;
4029 	cp->renameAllowed = obj->renameAllowed;
4030 	cp->unlinkAllowed = obj->unlinkAllowed;
4031 	cp->serial = obj->serial;
4032 	cp->nDataChunks = obj->nDataChunks;
4033 
4034 	if(obj->variantType == YAFFS_OBJECT_TYPE_FILE)
4035 		cp->fileSizeOrEquivalentObjectId = obj->variant.fileVariant.fileSize;
4036 	else if(obj->variantType == YAFFS_OBJECT_TYPE_HARDLINK)
4037 		cp->fileSizeOrEquivalentObjectId = obj->variant.hardLinkVariant.equivalentObjectId;
4038 }
4039 
4040 static void yaffs_CheckpointObjectToObject( yaffs_Object *obj,yaffs_CheckpointObject *cp)
4041 {
4042 
4043 	yaffs_Object *parent;
4044 
4045 	obj->objectId = cp->objectId;
4046 
4047 	if(cp->parentId)
4048 		parent = yaffs_FindOrCreateObjectByNumber(
4049 					obj->myDev,
4050 					cp->parentId,
4051 					YAFFS_OBJECT_TYPE_DIRECTORY);
4052 	else
4053 		parent = NULL;
4054 
4055 	if(parent)
4056 		yaffs_AddObjectToDirectory(parent, obj);
4057 
4058 	obj->chunkId = cp->chunkId;
4059 	obj->variantType = cp->variantType;
4060 	obj->deleted = cp->deleted;
4061 	obj->softDeleted = cp->softDeleted;
4062 	obj->unlinked = cp->unlinked;
4063 	obj->fake = cp->fake;
4064 	obj->renameAllowed = cp->renameAllowed;
4065 	obj->unlinkAllowed = cp->unlinkAllowed;
4066 	obj->serial = cp->serial;
4067 	obj->nDataChunks = cp->nDataChunks;
4068 
4069 	if(obj->variantType == YAFFS_OBJECT_TYPE_FILE)
4070 		obj->variant.fileVariant.fileSize = cp->fileSizeOrEquivalentObjectId;
4071 	else if(obj->variantType == YAFFS_OBJECT_TYPE_HARDLINK)
4072 		obj->variant.hardLinkVariant.equivalentObjectId = cp->fileSizeOrEquivalentObjectId;
4073 
4074 	if(obj->objectId >= YAFFS_NOBJECT_BUCKETS)
4075 		obj->lazyLoaded = 1;
4076 }
4077 
4078 
4079 
4080 static int yaffs_CheckpointTnodeWorker(yaffs_Object * in, yaffs_Tnode * tn,
4081 					__u32 level, int chunkOffset)
4082 {
4083 	int i;
4084 	yaffs_Device *dev = in->myDev;
4085 	int ok = 1;
4086 	int nTnodeBytes = (dev->tnodeWidth * YAFFS_NTNODES_LEVEL0)/8;
4087 
4088 	if (tn) {
4089 		if (level > 0) {
4090 
4091 			for (i = 0; i < YAFFS_NTNODES_INTERNAL && ok; i++){
4092 				if (tn->internal[i]) {
4093 					ok = yaffs_CheckpointTnodeWorker(in,
4094 							tn->internal[i],
4095 							level - 1,
4096 							(chunkOffset<<YAFFS_TNODES_INTERNAL_BITS) + i);
4097 				}
4098 			}
4099 		} else if (level == 0) {
4100 			__u32 baseOffset = chunkOffset <<  YAFFS_TNODES_LEVEL0_BITS;
4101 			/* printf("write tnode at %d\n",baseOffset); */
4102 			ok = (yaffs_CheckpointWrite(dev,&baseOffset,sizeof(baseOffset)) == sizeof(baseOffset));
4103 			if(ok)
4104 				ok = (yaffs_CheckpointWrite(dev,tn,nTnodeBytes) == nTnodeBytes);
4105 		}
4106 	}
4107 
4108 	return ok;
4109 
4110 }
4111 
4112 static int yaffs_WriteCheckpointTnodes(yaffs_Object *obj)
4113 {
4114 	__u32 endMarker = ~0;
4115 	int ok = 1;
4116 
4117 	if(obj->variantType == YAFFS_OBJECT_TYPE_FILE){
4118 		ok = yaffs_CheckpointTnodeWorker(obj,
4119 					    obj->variant.fileVariant.top,
4120 					    obj->variant.fileVariant.topLevel,
4121 					    0);
4122 		if(ok)
4123 			ok = (yaffs_CheckpointWrite(obj->myDev,&endMarker,sizeof(endMarker)) ==
4124 				sizeof(endMarker));
4125 	}
4126 
4127 	return ok ? 1 : 0;
4128 }
4129 
4130 static int yaffs_ReadCheckpointTnodes(yaffs_Object *obj)
4131 {
4132 	__u32 baseChunk;
4133 	int ok = 1;
4134 	yaffs_Device *dev = obj->myDev;
4135 	yaffs_FileStructure *fileStructPtr = &obj->variant.fileVariant;
4136 	yaffs_Tnode *tn;
4137 	int nread = 0;
4138 
4139 	ok = (yaffs_CheckpointRead(dev,&baseChunk,sizeof(baseChunk)) == sizeof(baseChunk));
4140 
4141 	while(ok && (~baseChunk)){
4142 		nread++;
4143 		/* Read level 0 tnode */
4144 
4145 
4146 		/* printf("read  tnode at %d\n",baseChunk); */
4147 		tn = yaffs_GetTnodeRaw(dev);
4148 		if(tn)
4149 			ok = (yaffs_CheckpointRead(dev,tn,(dev->tnodeWidth * YAFFS_NTNODES_LEVEL0)/8) ==
4150 			      (dev->tnodeWidth * YAFFS_NTNODES_LEVEL0)/8);
4151 		else
4152 			ok = 0;
4153 
4154 		if(tn && ok){
4155 			ok = yaffs_AddOrFindLevel0Tnode(dev,
4156 							fileStructPtr,
4157 							baseChunk,
4158 							tn) ? 1 : 0;
4159 
4160 		}
4161 
4162 		if(ok)
4163 			ok = (yaffs_CheckpointRead(dev,&baseChunk,sizeof(baseChunk)) == sizeof(baseChunk));
4164 
4165 	}
4166 
4167 	T(YAFFS_TRACE_CHECKPOINT,(
4168 		TSTR("Checkpoint read tnodes %d records, last %d. ok %d" TENDSTR),
4169 		nread,baseChunk,ok));
4170 
4171 	return ok ? 1 : 0;
4172 }
4173 
4174 
4175 static int yaffs_WriteCheckpointObjects(yaffs_Device *dev)
4176 {
4177 	yaffs_Object *obj;
4178 	yaffs_CheckpointObject cp;
4179 	int i;
4180 	int ok = 1;
4181 	struct list_head *lh;
4182 
4183 
4184 	/* Iterate through the objects in each hash entry,
4185 	 * dumping them to the checkpointing stream.
4186 	 */
4187 
4188 	 for(i = 0; ok &&  i <  YAFFS_NOBJECT_BUCKETS; i++){
4189 		list_for_each(lh, &dev->objectBucket[i].list) {
4190 			if (lh) {
4191 				obj = list_entry(lh, yaffs_Object, hashLink);
4192 				if (!obj->deferedFree) {
4193 					yaffs_ObjectToCheckpointObject(&cp,obj);
4194 					cp.structType = sizeof(cp);
4195 
4196 					T(YAFFS_TRACE_CHECKPOINT,(
4197 						TSTR("Checkpoint write object %d parent %d type %d chunk %d obj addr %x" TENDSTR),
4198 						cp.objectId,cp.parentId,cp.variantType,cp.chunkId,(unsigned) obj));
4199 
4200 					ok = (yaffs_CheckpointWrite(dev,&cp,sizeof(cp)) == sizeof(cp));
4201 
4202 					if(ok && obj->variantType == YAFFS_OBJECT_TYPE_FILE){
4203 						ok = yaffs_WriteCheckpointTnodes(obj);
4204 					}
4205 				}
4206 			}
4207 		}
4208 	 }
4209 
4210 	 /* Dump end of list */
4211 	memset(&cp,0xFF,sizeof(yaffs_CheckpointObject));
4212 	cp.structType = sizeof(cp);
4213 
4214 	if(ok)
4215 		ok = (yaffs_CheckpointWrite(dev,&cp,sizeof(cp)) == sizeof(cp));
4216 
4217 	return ok ? 1 : 0;
4218 }
4219 
4220 static int yaffs_ReadCheckpointObjects(yaffs_Device *dev)
4221 {
4222 	yaffs_Object *obj;
4223 	yaffs_CheckpointObject cp;
4224 	int ok = 1;
4225 	int done = 0;
4226 	yaffs_Object *hardList = NULL;
4227 
4228 	while(ok && !done) {
4229 		ok = (yaffs_CheckpointRead(dev,&cp,sizeof(cp)) == sizeof(cp));
4230 		if(cp.structType != sizeof(cp)) {
4231 			T(YAFFS_TRACE_CHECKPOINT,(TSTR("struct size %d instead of %d ok %d"TENDSTR),
4232 				cp.structType,sizeof(cp),ok));
4233 			ok = 0;
4234 		}
4235 
4236 		T(YAFFS_TRACE_CHECKPOINT,(TSTR("Checkpoint read object %d parent %d type %d chunk %d " TENDSTR),
4237 			cp.objectId,cp.parentId,cp.variantType,cp.chunkId));
4238 
4239 		if(ok && cp.objectId == ~0)
4240 			done = 1;
4241 		else if(ok){
4242 			obj = yaffs_FindOrCreateObjectByNumber(dev,cp.objectId, cp.variantType);
4243 			if(obj) {
4244 				yaffs_CheckpointObjectToObject(obj,&cp);
4245 				if(obj->variantType == YAFFS_OBJECT_TYPE_FILE) {
4246 					ok = yaffs_ReadCheckpointTnodes(obj);
4247 				} else if(obj->variantType == YAFFS_OBJECT_TYPE_HARDLINK) {
4248 					obj->hardLinks.next =
4249 						    (struct list_head *)
4250 						    hardList;
4251 					hardList = obj;
4252 				}
4253 
4254 			}
4255 		}
4256 	}
4257 
4258 	if(ok)
4259 		yaffs_HardlinkFixup(dev,hardList);
4260 
4261 	return ok ? 1 : 0;
4262 }
4263 
4264 static int yaffs_WriteCheckpointSum(yaffs_Device *dev)
4265 {
4266 	__u32 checkpointSum;
4267 	int ok;
4268 
4269 	yaffs_GetCheckpointSum(dev,&checkpointSum);
4270 
4271 	ok = (yaffs_CheckpointWrite(dev,&checkpointSum,sizeof(checkpointSum)) == sizeof(checkpointSum));
4272 
4273 	if(!ok)
4274 		return 0;
4275 
4276 	return 1;
4277 }
4278 
4279 static int yaffs_ReadCheckpointSum(yaffs_Device *dev)
4280 {
4281 	__u32 checkpointSum0;
4282 	__u32 checkpointSum1;
4283 	int ok;
4284 
4285 	yaffs_GetCheckpointSum(dev,&checkpointSum0);
4286 
4287 	ok = (yaffs_CheckpointRead(dev,&checkpointSum1,sizeof(checkpointSum1)) == sizeof(checkpointSum1));
4288 
4289 	if(!ok)
4290 		return 0;
4291 
4292 	if(checkpointSum0 != checkpointSum1)
4293 		return 0;
4294 
4295 	return 1;
4296 }
4297 
4298 
4299 static int yaffs_WriteCheckpointData(yaffs_Device *dev)
4300 {
4301 
4302 	int ok = 1;
4303 
4304 	if(dev->skipCheckpointWrite || !dev->isYaffs2){
4305 		T(YAFFS_TRACE_CHECKPOINT,(TSTR("skipping checkpoint write" TENDSTR)));
4306 		ok = 0;
4307 	}
4308 
4309 	if(ok)
4310 		ok = yaffs_CheckpointOpen(dev,1);
4311 
4312 	if(ok){
4313 		T(YAFFS_TRACE_CHECKPOINT,(TSTR("write checkpoint validity" TENDSTR)));
4314 		ok = yaffs_WriteCheckpointValidityMarker(dev,1);
4315 	}
4316 	if(ok){
4317 		T(YAFFS_TRACE_CHECKPOINT,(TSTR("write checkpoint device" TENDSTR)));
4318 		ok = yaffs_WriteCheckpointDevice(dev);
4319 	}
4320 	if(ok){
4321 		T(YAFFS_TRACE_CHECKPOINT,(TSTR("write checkpoint objects" TENDSTR)));
4322 		ok = yaffs_WriteCheckpointObjects(dev);
4323 	}
4324 	if(ok){
4325 		T(YAFFS_TRACE_CHECKPOINT,(TSTR("write checkpoint validity" TENDSTR)));
4326 		ok = yaffs_WriteCheckpointValidityMarker(dev,0);
4327 	}
4328 
4329 	if(ok){
4330 		ok = yaffs_WriteCheckpointSum(dev);
4331 	}
4332 
4333 
4334 	if(!yaffs_CheckpointClose(dev))
4335 		 ok = 0;
4336 
4337 	if(ok)
4338 		dev->isCheckpointed = 1;
4339 	 else
4340 		dev->isCheckpointed = 0;
4341 
4342 	return dev->isCheckpointed;
4343 }
4344 
4345 static int yaffs_ReadCheckpointData(yaffs_Device *dev)
4346 {
4347 	int ok = 1;
4348 
4349 	if(dev->skipCheckpointRead || !dev->isYaffs2){
4350 		T(YAFFS_TRACE_CHECKPOINT,(TSTR("skipping checkpoint read" TENDSTR)));
4351 		ok = 0;
4352 	}
4353 
4354 	if(ok)
4355 		ok = yaffs_CheckpointOpen(dev,0); /* open for read */
4356 
4357 	if(ok){
4358 		T(YAFFS_TRACE_CHECKPOINT,(TSTR("read checkpoint validity" TENDSTR)));
4359 		ok = yaffs_ReadCheckpointValidityMarker(dev,1);
4360 	}
4361 	if(ok){
4362 		T(YAFFS_TRACE_CHECKPOINT,(TSTR("read checkpoint device" TENDSTR)));
4363 		ok = yaffs_ReadCheckpointDevice(dev);
4364 	}
4365 	if(ok){
4366 		T(YAFFS_TRACE_CHECKPOINT,(TSTR("read checkpoint objects" TENDSTR)));
4367 		ok = yaffs_ReadCheckpointObjects(dev);
4368 	}
4369 	if(ok){
4370 		T(YAFFS_TRACE_CHECKPOINT,(TSTR("read checkpoint validity" TENDSTR)));
4371 		ok = yaffs_ReadCheckpointValidityMarker(dev,0);
4372 	}
4373 
4374 	if(ok){
4375 		ok = yaffs_ReadCheckpointSum(dev);
4376 		T(YAFFS_TRACE_CHECKPOINT,(TSTR("read checkpoint checksum %d" TENDSTR),ok));
4377 	}
4378 
4379 	if(!yaffs_CheckpointClose(dev))
4380 		ok = 0;
4381 
4382 	if(ok)
4383 		dev->isCheckpointed = 1;
4384 	 else
4385 		dev->isCheckpointed = 0;
4386 
4387 	return ok ? 1 : 0;
4388 
4389 }
4390 
4391 static void yaffs_InvalidateCheckpoint(yaffs_Device *dev)
4392 {
4393 	if(dev->isCheckpointed ||
4394 	   dev->blocksInCheckpoint > 0){
4395 		dev->isCheckpointed = 0;
4396 		yaffs_CheckpointInvalidateStream(dev);
4397 		if(dev->superBlock && dev->markSuperBlockDirty)
4398 			dev->markSuperBlockDirty(dev->superBlock);
4399 	}
4400 }
4401 
4402 
4403 int yaffs_CheckpointSave(yaffs_Device *dev)
4404 {
4405 
4406 	T(YAFFS_TRACE_CHECKPOINT,(TSTR("save entry: isCheckpointed %d"TENDSTR),dev->isCheckpointed));
4407 
4408 	yaffs_VerifyObjects(dev);
4409 	yaffs_VerifyBlocks(dev);
4410 	yaffs_VerifyFreeChunks(dev);
4411 
4412 	if(!dev->isCheckpointed) {
4413 		yaffs_InvalidateCheckpoint(dev);
4414 		yaffs_WriteCheckpointData(dev);
4415 	}
4416 
4417 	T(YAFFS_TRACE_ALWAYS,(TSTR("save exit: isCheckpointed %d"TENDSTR),dev->isCheckpointed));
4418 
4419 	return dev->isCheckpointed;
4420 }
4421 
4422 int yaffs_CheckpointRestore(yaffs_Device *dev)
4423 {
4424 	int retval;
4425 	T(YAFFS_TRACE_CHECKPOINT,(TSTR("restore entry: isCheckpointed %d"TENDSTR),dev->isCheckpointed));
4426 
4427 	retval = yaffs_ReadCheckpointData(dev);
4428 
4429 	if(dev->isCheckpointed){
4430 		yaffs_VerifyObjects(dev);
4431 		yaffs_VerifyBlocks(dev);
4432 		yaffs_VerifyFreeChunks(dev);
4433 	}
4434 
4435 	T(YAFFS_TRACE_CHECKPOINT,(TSTR("restore exit: isCheckpointed %d"TENDSTR),dev->isCheckpointed));
4436 
4437 	return retval;
4438 }
4439 
4440 /*--------------------- File read/write ------------------------
4441  * Read and write have very similar structures.
4442  * In general the read/write has three parts to it
4443  * An incomplete chunk to start with (if the read/write is not chunk-aligned)
4444  * Some complete chunks
4445  * An incomplete chunk to end off with
4446  *
4447  * Curve-balls: the first chunk might also be the last chunk.
4448  */
4449 
4450 int yaffs_ReadDataFromFile(yaffs_Object * in, __u8 * buffer, loff_t offset,
4451 			   int nBytes)
4452 {
4453 
4454 	__u32 chunk = 0;
4455 	__u32 start = 0;
4456 	int nToCopy;
4457 	int n = nBytes;
4458 	int nDone = 0;
4459 	yaffs_ChunkCache *cache;
4460 
4461 	yaffs_Device *dev;
4462 
4463 	dev = in->myDev;
4464 
4465 	while (n > 0) {
4466 		//chunk = offset / dev->nDataBytesPerChunk + 1;
4467 		//start = offset % dev->nDataBytesPerChunk;
4468 		yaffs_AddrToChunk(dev,offset,&chunk,&start);
4469 		chunk++;
4470 
4471 		/* OK now check for the curveball where the start and end are in
4472 		 * the same chunk.
4473 		 */
4474 		if ((start + n) < dev->nDataBytesPerChunk) {
4475 			nToCopy = n;
4476 		} else {
4477 			nToCopy = dev->nDataBytesPerChunk - start;
4478 		}
4479 
4480 		cache = yaffs_FindChunkCache(in, chunk);
4481 
4482 		/* If the chunk is already in the cache or it is less than a whole chunk
4483 		 * then use the cache (if there is caching)
4484 		 * else bypass the cache.
4485 		 */
4486 		if (cache || nToCopy != dev->nDataBytesPerChunk) {
4487 			if (dev->nShortOpCaches > 0) {
4488 
4489 				/* If we can't find the data in the cache, then load it up. */
4490 
4491 				if (!cache) {
4492 					cache = yaffs_GrabChunkCache(in->myDev);
4493 					cache->object = in;
4494 					cache->chunkId = chunk;
4495 					cache->dirty = 0;
4496 					cache->locked = 0;
4497 					yaffs_ReadChunkDataFromObject(in, chunk,
4498 								      cache->
4499 								      data);
4500 					cache->nBytes = 0;
4501 				}
4502 
4503 				yaffs_UseChunkCache(dev, cache, 0);
4504 
4505 				cache->locked = 1;
4506 
4507 #ifdef CONFIG_YAFFS_WINCE
4508 				yfsd_UnlockYAFFS(TRUE);
4509 #endif
4510 				memcpy(buffer, &cache->data[start], nToCopy);
4511 
4512 #ifdef CONFIG_YAFFS_WINCE
4513 				yfsd_LockYAFFS(TRUE);
4514 #endif
4515 				cache->locked = 0;
4516 			} else {
4517 				/* Read into the local buffer then copy..*/
4518 
4519 				__u8 *localBuffer =
4520 				    yaffs_GetTempBuffer(dev, __LINE__);
4521 				yaffs_ReadChunkDataFromObject(in, chunk,
4522 							      localBuffer);
4523 #ifdef CONFIG_YAFFS_WINCE
4524 				yfsd_UnlockYAFFS(TRUE);
4525 #endif
4526 				memcpy(buffer, &localBuffer[start], nToCopy);
4527 
4528 #ifdef CONFIG_YAFFS_WINCE
4529 				yfsd_LockYAFFS(TRUE);
4530 #endif
4531 				yaffs_ReleaseTempBuffer(dev, localBuffer,
4532 							__LINE__);
4533 			}
4534 
4535 		} else {
4536 #ifdef CONFIG_YAFFS_WINCE
4537 			__u8 *localBuffer = yaffs_GetTempBuffer(dev, __LINE__);
4538 
4539 			/* Under WinCE can't do direct transfer. Need to use a local buffer.
4540 			 * This is because we otherwise screw up WinCE's memory mapper
4541 			 */
4542 			yaffs_ReadChunkDataFromObject(in, chunk, localBuffer);
4543 
4544 #ifdef CONFIG_YAFFS_WINCE
4545 			yfsd_UnlockYAFFS(TRUE);
4546 #endif
4547 			memcpy(buffer, localBuffer, dev->nDataBytesPerChunk);
4548 
4549 #ifdef CONFIG_YAFFS_WINCE
4550 			yfsd_LockYAFFS(TRUE);
4551 			yaffs_ReleaseTempBuffer(dev, localBuffer, __LINE__);
4552 #endif
4553 
4554 #else
4555 			/* A full chunk. Read directly into the supplied buffer. */
4556 			yaffs_ReadChunkDataFromObject(in, chunk, buffer);
4557 #endif
4558 		}
4559 
4560 		n -= nToCopy;
4561 		offset += nToCopy;
4562 		buffer += nToCopy;
4563 		nDone += nToCopy;
4564 
4565 	}
4566 
4567 	return nDone;
4568 }
4569 
4570 int yaffs_WriteDataToFile(yaffs_Object * in, const __u8 * buffer, loff_t offset,
4571 			  int nBytes, int writeThrough)
4572 {
4573 
4574 	__u32 chunk = 0;
4575 	__u32 start = 0;
4576 	int nToCopy;
4577 	int n = nBytes;
4578 	int nDone = 0;
4579 	int nToWriteBack;
4580 	int startOfWrite = offset;
4581 	int chunkWritten = 0;
4582 	int nBytesRead;
4583 
4584 	yaffs_Device *dev;
4585 
4586 	dev = in->myDev;
4587 
4588 	while (n > 0 && chunkWritten >= 0) {
4589 		//chunk = offset / dev->nDataBytesPerChunk + 1;
4590 		//start = offset % dev->nDataBytesPerChunk;
4591 		yaffs_AddrToChunk(dev,offset,&chunk,&start);
4592 		chunk++;
4593 
4594 		/* OK now check for the curveball where the start and end are in
4595 		 * the same chunk.
4596 		 */
4597 
4598 		if ((start + n) < dev->nDataBytesPerChunk) {
4599 			nToCopy = n;
4600 
4601 			/* Now folks, to calculate how many bytes to write back....
4602 			 * If we're overwriting and not writing to then end of file then
4603 			 * we need to write back as much as was there before.
4604 			 */
4605 
4606 			nBytesRead =
4607 			    in->variant.fileVariant.fileSize -
4608 			    ((chunk - 1) * dev->nDataBytesPerChunk);
4609 
4610 			if (nBytesRead > dev->nDataBytesPerChunk) {
4611 				nBytesRead = dev->nDataBytesPerChunk;
4612 			}
4613 
4614 			nToWriteBack =
4615 			    (nBytesRead >
4616 			     (start + n)) ? nBytesRead : (start + n);
4617 
4618 		} else {
4619 			nToCopy = dev->nDataBytesPerChunk - start;
4620 			nToWriteBack = dev->nDataBytesPerChunk;
4621 		}
4622 
4623 		if (nToCopy != dev->nDataBytesPerChunk) {
4624 			/* An incomplete start or end chunk (or maybe both start and end chunk) */
4625 			if (dev->nShortOpCaches > 0) {
4626 				yaffs_ChunkCache *cache;
4627 				/* If we can't find the data in the cache, then load the cache */
4628 				cache = yaffs_FindChunkCache(in, chunk);
4629 
4630 				if (!cache
4631 				    && yaffs_CheckSpaceForAllocation(in->
4632 								     myDev)) {
4633 					cache = yaffs_GrabChunkCache(in->myDev);
4634 					cache->object = in;
4635 					cache->chunkId = chunk;
4636 					cache->dirty = 0;
4637 					cache->locked = 0;
4638 					yaffs_ReadChunkDataFromObject(in, chunk,
4639 								      cache->
4640 								      data);
4641 				}
4642 				else if(cache &&
4643 					!cache->dirty &&
4644 					!yaffs_CheckSpaceForAllocation(in->myDev)){
4645 					/* Drop the cache if it was a read cache item and
4646 					 * no space check has been made for it.
4647 					 */
4648 					 cache = NULL;
4649 				}
4650 
4651 				if (cache) {
4652 					yaffs_UseChunkCache(dev, cache, 1);
4653 					cache->locked = 1;
4654 #ifdef CONFIG_YAFFS_WINCE
4655 					yfsd_UnlockYAFFS(TRUE);
4656 #endif
4657 
4658 					memcpy(&cache->data[start], buffer,
4659 					       nToCopy);
4660 
4661 #ifdef CONFIG_YAFFS_WINCE
4662 					yfsd_LockYAFFS(TRUE);
4663 #endif
4664 					cache->locked = 0;
4665 					cache->nBytes = nToWriteBack;
4666 
4667 					if (writeThrough) {
4668 						chunkWritten =
4669 						    yaffs_WriteChunkDataToObject
4670 						    (cache->object,
4671 						     cache->chunkId,
4672 						     cache->data, cache->nBytes,
4673 						     1);
4674 						cache->dirty = 0;
4675 					}
4676 
4677 				} else {
4678 					chunkWritten = -1;	/* fail the write */
4679 				}
4680 			} else {
4681 				/* An incomplete start or end chunk (or maybe both start and end chunk)
4682 				 * Read into the local buffer then copy, then copy over and write back.
4683 				 */
4684 
4685 				__u8 *localBuffer =
4686 				    yaffs_GetTempBuffer(dev, __LINE__);
4687 
4688 				yaffs_ReadChunkDataFromObject(in, chunk,
4689 							      localBuffer);
4690 
4691 #ifdef CONFIG_YAFFS_WINCE
4692 				yfsd_UnlockYAFFS(TRUE);
4693 #endif
4694 
4695 				memcpy(&localBuffer[start], buffer, nToCopy);
4696 
4697 #ifdef CONFIG_YAFFS_WINCE
4698 				yfsd_LockYAFFS(TRUE);
4699 #endif
4700 				chunkWritten =
4701 				    yaffs_WriteChunkDataToObject(in, chunk,
4702 								 localBuffer,
4703 								 nToWriteBack,
4704 								 0);
4705 
4706 				yaffs_ReleaseTempBuffer(dev, localBuffer,
4707 							__LINE__);
4708 
4709 			}
4710 
4711 		} else {
4712 
4713 #ifdef CONFIG_YAFFS_WINCE
4714 			/* Under WinCE can't do direct transfer. Need to use a local buffer.
4715 			 * This is because we otherwise screw up WinCE's memory mapper
4716 			 */
4717 			__u8 *localBuffer = yaffs_GetTempBuffer(dev, __LINE__);
4718 #ifdef CONFIG_YAFFS_WINCE
4719 			yfsd_UnlockYAFFS(TRUE);
4720 #endif
4721 			memcpy(localBuffer, buffer, dev->nDataBytesPerChunk);
4722 #ifdef CONFIG_YAFFS_WINCE
4723 			yfsd_LockYAFFS(TRUE);
4724 #endif
4725 			chunkWritten =
4726 			    yaffs_WriteChunkDataToObject(in, chunk, localBuffer,
4727 							 dev->nDataBytesPerChunk,
4728 							 0);
4729 			yaffs_ReleaseTempBuffer(dev, localBuffer, __LINE__);
4730 #else
4731 			/* A full chunk. Write directly from the supplied buffer. */
4732 			chunkWritten =
4733 			    yaffs_WriteChunkDataToObject(in, chunk, buffer,
4734 							 dev->nDataBytesPerChunk,
4735 							 0);
4736 #endif
4737 			/* Since we've overwritten the cached data, we better invalidate it. */
4738 			yaffs_InvalidateChunkCache(in, chunk);
4739 		}
4740 
4741 		if (chunkWritten >= 0) {
4742 			n -= nToCopy;
4743 			offset += nToCopy;
4744 			buffer += nToCopy;
4745 			nDone += nToCopy;
4746 		}
4747 
4748 	}
4749 
4750 	/* Update file object */
4751 
4752 	if ((startOfWrite + nDone) > in->variant.fileVariant.fileSize) {
4753 		in->variant.fileVariant.fileSize = (startOfWrite + nDone);
4754 	}
4755 
4756 	in->dirty = 1;
4757 
4758 	return nDone;
4759 }
4760 
4761 
4762 /* ---------------------- File resizing stuff ------------------ */
4763 
4764 static void yaffs_PruneResizedChunks(yaffs_Object * in, int newSize)
4765 {
4766 
4767 	yaffs_Device *dev = in->myDev;
4768 	int oldFileSize = in->variant.fileVariant.fileSize;
4769 
4770 	int lastDel = 1 + (oldFileSize - 1) / dev->nDataBytesPerChunk;
4771 
4772 	int startDel = 1 + (newSize + dev->nDataBytesPerChunk - 1) /
4773 	    dev->nDataBytesPerChunk;
4774 	int i;
4775 	int chunkId;
4776 
4777 	/* Delete backwards so that we don't end up with holes if
4778 	 * power is lost part-way through the operation.
4779 	 */
4780 	for (i = lastDel; i >= startDel; i--) {
4781 		/* NB this could be optimised somewhat,
4782 		 * eg. could retrieve the tags and write them without
4783 		 * using yaffs_DeleteChunk
4784 		 */
4785 
4786 		chunkId = yaffs_FindAndDeleteChunkInFile(in, i, NULL);
4787 		if (chunkId > 0) {
4788 			if (chunkId <
4789 			    (dev->internalStartBlock * dev->nChunksPerBlock)
4790 			    || chunkId >=
4791 			    ((dev->internalEndBlock +
4792 			      1) * dev->nChunksPerBlock)) {
4793 				T(YAFFS_TRACE_ALWAYS,
4794 				  (TSTR("Found daft chunkId %d for %d" TENDSTR),
4795 				   chunkId, i));
4796 			} else {
4797 				in->nDataChunks--;
4798 				yaffs_DeleteChunk(dev, chunkId, 1, __LINE__);
4799 			}
4800 		}
4801 	}
4802 
4803 }
4804 
4805 int yaffs_ResizeFile(yaffs_Object * in, loff_t newSize)
4806 {
4807 
4808 	int oldFileSize = in->variant.fileVariant.fileSize;
4809 	__u32 newSizeOfPartialChunk = 0;
4810 	__u32 newFullChunks = 0;
4811 
4812 	yaffs_Device *dev = in->myDev;
4813 
4814 	yaffs_AddrToChunk(dev, newSize, &newFullChunks, &newSizeOfPartialChunk);
4815 
4816 	yaffs_FlushFilesChunkCache(in);
4817 	yaffs_InvalidateWholeChunkCache(in);
4818 
4819 	yaffs_CheckGarbageCollection(dev);
4820 
4821 	if (in->variantType != YAFFS_OBJECT_TYPE_FILE) {
4822 		return yaffs_GetFileSize(in);
4823 	}
4824 
4825 	if (newSize == oldFileSize) {
4826 		return oldFileSize;
4827 	}
4828 
4829 	if (newSize < oldFileSize) {
4830 
4831 		yaffs_PruneResizedChunks(in, newSize);
4832 
4833 		if (newSizeOfPartialChunk != 0) {
4834 			int lastChunk = 1 + newFullChunks;
4835 
4836 			__u8 *localBuffer = yaffs_GetTempBuffer(dev, __LINE__);
4837 
4838 			/* Got to read and rewrite the last chunk with its new size and zero pad */
4839 			yaffs_ReadChunkDataFromObject(in, lastChunk,
4840 						      localBuffer);
4841 
4842 			memset(localBuffer + newSizeOfPartialChunk, 0,
4843 			       dev->nDataBytesPerChunk - newSizeOfPartialChunk);
4844 
4845 			yaffs_WriteChunkDataToObject(in, lastChunk, localBuffer,
4846 						     newSizeOfPartialChunk, 1);
4847 
4848 			yaffs_ReleaseTempBuffer(dev, localBuffer, __LINE__);
4849 		}
4850 
4851 		in->variant.fileVariant.fileSize = newSize;
4852 
4853 		yaffs_PruneFileStructure(dev, &in->variant.fileVariant);
4854 	} else {
4855 		/* newsSize > oldFileSize */
4856 		in->variant.fileVariant.fileSize = newSize;
4857 	}
4858 
4859 
4860 
4861 	/* Write a new object header.
4862 	 * show we've shrunk the file, if need be
4863 	 * Do this only if the file is not in the deleted directories.
4864 	 */
4865 	if (in->parent->objectId != YAFFS_OBJECTID_UNLINKED &&
4866 	    in->parent->objectId != YAFFS_OBJECTID_DELETED) {
4867 		yaffs_UpdateObjectHeader(in, NULL, 0,
4868 					 (newSize < oldFileSize) ? 1 : 0, 0);
4869 	}
4870 
4871 	return YAFFS_OK;
4872 }
4873 
4874 loff_t yaffs_GetFileSize(yaffs_Object * obj)
4875 {
4876 	obj = yaffs_GetEquivalentObject(obj);
4877 
4878 	switch (obj->variantType) {
4879 	case YAFFS_OBJECT_TYPE_FILE:
4880 		return obj->variant.fileVariant.fileSize;
4881 	case YAFFS_OBJECT_TYPE_SYMLINK:
4882 		return yaffs_strlen(obj->variant.symLinkVariant.alias);
4883 	default:
4884 		return 0;
4885 	}
4886 }
4887 
4888 
4889 
4890 int yaffs_FlushFile(yaffs_Object * in, int updateTime)
4891 {
4892 	int retVal;
4893 	if (in->dirty) {
4894 		yaffs_FlushFilesChunkCache(in);
4895 		if (updateTime) {
4896 #ifdef CONFIG_YAFFS_WINCE
4897 			yfsd_WinFileTimeNow(in->win_mtime);
4898 #else
4899 
4900 			in->yst_mtime = Y_CURRENT_TIME;
4901 
4902 #endif
4903 		}
4904 
4905 		retVal =
4906 		    (yaffs_UpdateObjectHeader(in, NULL, 0, 0, 0) >=
4907 		     0) ? YAFFS_OK : YAFFS_FAIL;
4908 	} else {
4909 		retVal = YAFFS_OK;
4910 	}
4911 
4912 	return retVal;
4913 
4914 }
4915 
4916 static int yaffs_DoGenericObjectDeletion(yaffs_Object * in)
4917 {
4918 
4919 	/* First off, invalidate the file's data in the cache, without flushing. */
4920 	yaffs_InvalidateWholeChunkCache(in);
4921 
4922 	if (in->myDev->isYaffs2 && (in->parent != in->myDev->deletedDir)) {
4923 		/* Move to the unlinked directory so we have a record that it was deleted. */
4924 		yaffs_ChangeObjectName(in, in->myDev->deletedDir,"deleted", 0, 0);
4925 
4926 	}
4927 
4928 	yaffs_RemoveObjectFromDirectory(in);
4929 	yaffs_DeleteChunk(in->myDev, in->chunkId, 1, __LINE__);
4930 	in->chunkId = -1;
4931 
4932 	yaffs_FreeObject(in);
4933 	return YAFFS_OK;
4934 
4935 }
4936 
4937 /* yaffs_DeleteFile deletes the whole file data
4938  * and the inode associated with the file.
4939  * It does not delete the links associated with the file.
4940  */
4941 static int yaffs_UnlinkFile(yaffs_Object * in)
4942 {
4943 
4944 	int retVal;
4945 	int immediateDeletion = 0;
4946 
4947 	if (1) {
4948 /* XXX U-BOOT XXX */
4949 #if 0
4950 #ifdef __KERNEL__
4951 		if (!in->myInode) {
4952 			immediateDeletion = 1;
4953 
4954 		}
4955 #endif
4956 #else
4957 		if (in->inUse <= 0) {
4958 			immediateDeletion = 1;
4959 
4960 		}
4961 #endif
4962 		if (immediateDeletion) {
4963 			retVal =
4964 			    yaffs_ChangeObjectName(in, in->myDev->deletedDir,
4965 						   "deleted", 0, 0);
4966 			T(YAFFS_TRACE_TRACING,
4967 			  (TSTR("yaffs: immediate deletion of file %d" TENDSTR),
4968 			   in->objectId));
4969 			in->deleted = 1;
4970 			in->myDev->nDeletedFiles++;
4971 			if (0 && in->myDev->isYaffs2) {
4972 				yaffs_ResizeFile(in, 0);
4973 			}
4974 			yaffs_SoftDeleteFile(in);
4975 		} else {
4976 			retVal =
4977 			    yaffs_ChangeObjectName(in, in->myDev->unlinkedDir,
4978 						   "unlinked", 0, 0);
4979 		}
4980 
4981 	}
4982 	return retVal;
4983 }
4984 
4985 int yaffs_DeleteFile(yaffs_Object * in)
4986 {
4987 	int retVal = YAFFS_OK;
4988 
4989 	if (in->nDataChunks > 0) {
4990 		/* Use soft deletion if there is data in the file */
4991 		if (!in->unlinked) {
4992 			retVal = yaffs_UnlinkFile(in);
4993 		}
4994 		if (retVal == YAFFS_OK && in->unlinked && !in->deleted) {
4995 			in->deleted = 1;
4996 			in->myDev->nDeletedFiles++;
4997 			yaffs_SoftDeleteFile(in);
4998 		}
4999 		return in->deleted ? YAFFS_OK : YAFFS_FAIL;
5000 	} else {
5001 		/* The file has no data chunks so we toss it immediately */
5002 		yaffs_FreeTnode(in->myDev, in->variant.fileVariant.top);
5003 		in->variant.fileVariant.top = NULL;
5004 		yaffs_DoGenericObjectDeletion(in);
5005 
5006 		return YAFFS_OK;
5007 	}
5008 }
5009 
5010 static int yaffs_DeleteDirectory(yaffs_Object * in)
5011 {
5012 	/* First check that the directory is empty. */
5013 	if (list_empty(&in->variant.directoryVariant.children)) {
5014 		return yaffs_DoGenericObjectDeletion(in);
5015 	}
5016 
5017 	return YAFFS_FAIL;
5018 
5019 }
5020 
5021 static int yaffs_DeleteSymLink(yaffs_Object * in)
5022 {
5023 	YFREE(in->variant.symLinkVariant.alias);
5024 
5025 	return yaffs_DoGenericObjectDeletion(in);
5026 }
5027 
5028 static int yaffs_DeleteHardLink(yaffs_Object * in)
5029 {
5030 	/* remove this hardlink from the list assocaited with the equivalent
5031 	 * object
5032 	 */
5033 	list_del(&in->hardLinks);
5034 	return yaffs_DoGenericObjectDeletion(in);
5035 }
5036 
5037 static void yaffs_DestroyObject(yaffs_Object * obj)
5038 {
5039 	switch (obj->variantType) {
5040 	case YAFFS_OBJECT_TYPE_FILE:
5041 		yaffs_DeleteFile(obj);
5042 		break;
5043 	case YAFFS_OBJECT_TYPE_DIRECTORY:
5044 		yaffs_DeleteDirectory(obj);
5045 		break;
5046 	case YAFFS_OBJECT_TYPE_SYMLINK:
5047 		yaffs_DeleteSymLink(obj);
5048 		break;
5049 	case YAFFS_OBJECT_TYPE_HARDLINK:
5050 		yaffs_DeleteHardLink(obj);
5051 		break;
5052 	case YAFFS_OBJECT_TYPE_SPECIAL:
5053 		yaffs_DoGenericObjectDeletion(obj);
5054 		break;
5055 	case YAFFS_OBJECT_TYPE_UNKNOWN:
5056 		break;		/* should not happen. */
5057 	}
5058 }
5059 
5060 static int yaffs_UnlinkWorker(yaffs_Object * obj)
5061 {
5062 
5063 	if (obj->variantType == YAFFS_OBJECT_TYPE_HARDLINK) {
5064 		return yaffs_DeleteHardLink(obj);
5065 	} else if (!list_empty(&obj->hardLinks)) {
5066 		/* Curve ball: We're unlinking an object that has a hardlink.
5067 		 *
5068 		 * This problem arises because we are not strictly following
5069 		 * The Linux link/inode model.
5070 		 *
5071 		 * We can't really delete the object.
5072 		 * Instead, we do the following:
5073 		 * - Select a hardlink.
5074 		 * - Unhook it from the hard links
5075 		 * - Unhook it from its parent directory (so that the rename can work)
5076 		 * - Rename the object to the hardlink's name.
5077 		 * - Delete the hardlink
5078 		 */
5079 
5080 		yaffs_Object *hl;
5081 		int retVal;
5082 		YCHAR name[YAFFS_MAX_NAME_LENGTH + 1];
5083 
5084 		hl = list_entry(obj->hardLinks.next, yaffs_Object, hardLinks);
5085 
5086 		list_del_init(&hl->hardLinks);
5087 		list_del_init(&hl->siblings);
5088 
5089 		yaffs_GetObjectName(hl, name, YAFFS_MAX_NAME_LENGTH + 1);
5090 
5091 		retVal = yaffs_ChangeObjectName(obj, hl->parent, name, 0, 0);
5092 
5093 		if (retVal == YAFFS_OK) {
5094 			retVal = yaffs_DoGenericObjectDeletion(hl);
5095 		}
5096 		return retVal;
5097 
5098 	} else {
5099 		switch (obj->variantType) {
5100 		case YAFFS_OBJECT_TYPE_FILE:
5101 			return yaffs_UnlinkFile(obj);
5102 			break;
5103 		case YAFFS_OBJECT_TYPE_DIRECTORY:
5104 			return yaffs_DeleteDirectory(obj);
5105 			break;
5106 		case YAFFS_OBJECT_TYPE_SYMLINK:
5107 			return yaffs_DeleteSymLink(obj);
5108 			break;
5109 		case YAFFS_OBJECT_TYPE_SPECIAL:
5110 			return yaffs_DoGenericObjectDeletion(obj);
5111 			break;
5112 		case YAFFS_OBJECT_TYPE_HARDLINK:
5113 		case YAFFS_OBJECT_TYPE_UNKNOWN:
5114 		default:
5115 			return YAFFS_FAIL;
5116 		}
5117 	}
5118 }
5119 
5120 
5121 static int yaffs_UnlinkObject( yaffs_Object *obj)
5122 {
5123 
5124 	if (obj && obj->unlinkAllowed) {
5125 		return yaffs_UnlinkWorker(obj);
5126 	}
5127 
5128 	return YAFFS_FAIL;
5129 
5130 }
5131 int yaffs_Unlink(yaffs_Object * dir, const YCHAR * name)
5132 {
5133 	yaffs_Object *obj;
5134 
5135 	obj = yaffs_FindObjectByName(dir, name);
5136 	return yaffs_UnlinkObject(obj);
5137 }
5138 
5139 /*----------------------- Initialisation Scanning ---------------------- */
5140 
5141 static void yaffs_HandleShadowedObject(yaffs_Device * dev, int objId,
5142 				       int backwardScanning)
5143 {
5144 	yaffs_Object *obj;
5145 
5146 	if (!backwardScanning) {
5147 		/* Handle YAFFS1 forward scanning case
5148 		 * For YAFFS1 we always do the deletion
5149 		 */
5150 
5151 	} else {
5152 		/* Handle YAFFS2 case (backward scanning)
5153 		 * If the shadowed object exists then ignore.
5154 		 */
5155 		if (yaffs_FindObjectByNumber(dev, objId)) {
5156 			return;
5157 		}
5158 	}
5159 
5160 	/* Let's create it (if it does not exist) assuming it is a file so that it can do shrinking etc.
5161 	 * We put it in unlinked dir to be cleaned up after the scanning
5162 	 */
5163 	obj =
5164 	    yaffs_FindOrCreateObjectByNumber(dev, objId,
5165 					     YAFFS_OBJECT_TYPE_FILE);
5166 	yaffs_AddObjectToDirectory(dev->unlinkedDir, obj);
5167 	obj->variant.fileVariant.shrinkSize = 0;
5168 	obj->valid = 1;		/* So that we don't read any other info for this file */
5169 
5170 }
5171 
5172 typedef struct {
5173 	int seq;
5174 	int block;
5175 } yaffs_BlockIndex;
5176 
5177 
5178 static void yaffs_HardlinkFixup(yaffs_Device *dev, yaffs_Object *hardList)
5179 {
5180 	yaffs_Object *hl;
5181 	yaffs_Object *in;
5182 
5183 	while (hardList) {
5184 		hl = hardList;
5185 		hardList = (yaffs_Object *) (hardList->hardLinks.next);
5186 
5187 		in = yaffs_FindObjectByNumber(dev,
5188 					      hl->variant.hardLinkVariant.
5189 					      equivalentObjectId);
5190 
5191 		if (in) {
5192 			/* Add the hardlink pointers */
5193 			hl->variant.hardLinkVariant.equivalentObject = in;
5194 			list_add(&hl->hardLinks, &in->hardLinks);
5195 		} else {
5196 			/* Todo Need to report/handle this better.
5197 			 * Got a problem... hardlink to a non-existant object
5198 			 */
5199 			hl->variant.hardLinkVariant.equivalentObject = NULL;
5200 			INIT_LIST_HEAD(&hl->hardLinks);
5201 
5202 		}
5203 
5204 	}
5205 
5206 }
5207 
5208 
5209 
5210 
5211 
5212 static int ybicmp(const void *a, const void *b){
5213     register int aseq = ((yaffs_BlockIndex *)a)->seq;
5214     register int bseq = ((yaffs_BlockIndex *)b)->seq;
5215     register int ablock = ((yaffs_BlockIndex *)a)->block;
5216     register int bblock = ((yaffs_BlockIndex *)b)->block;
5217     if( aseq == bseq )
5218 	return ablock - bblock;
5219     else
5220 	return aseq - bseq;
5221 
5222 }
5223 
5224 static int yaffs_Scan(yaffs_Device * dev)
5225 {
5226 	yaffs_ExtendedTags tags;
5227 	int blk;
5228 	int blockIterator;
5229 	int startIterator;
5230 	int endIterator;
5231 	int nBlocksToScan = 0;
5232 
5233 	int chunk;
5234 	int c;
5235 	int deleted;
5236 	yaffs_BlockState state;
5237 	yaffs_Object *hardList = NULL;
5238 	yaffs_BlockInfo *bi;
5239 	int sequenceNumber;
5240 	yaffs_ObjectHeader *oh;
5241 	yaffs_Object *in;
5242 	yaffs_Object *parent;
5243 	int nBlocks = dev->internalEndBlock - dev->internalStartBlock + 1;
5244 
5245 	int alloc_failed = 0;
5246 
5247 
5248 	__u8 *chunkData;
5249 
5250 	yaffs_BlockIndex *blockIndex = NULL;
5251 
5252 	if (dev->isYaffs2) {
5253 		T(YAFFS_TRACE_SCAN,
5254 		  (TSTR("yaffs_Scan is not for YAFFS2!" TENDSTR)));
5255 		return YAFFS_FAIL;
5256 	}
5257 
5258 	//TODO  Throw all the yaffs2 stuuf out of yaffs_Scan since it is only for yaffs1 format.
5259 
5260 	T(YAFFS_TRACE_SCAN,
5261 	  (TSTR("yaffs_Scan starts  intstartblk %d intendblk %d..." TENDSTR),
5262 	   dev->internalStartBlock, dev->internalEndBlock));
5263 
5264 	chunkData = yaffs_GetTempBuffer(dev, __LINE__);
5265 
5266 	dev->sequenceNumber = YAFFS_LOWEST_SEQUENCE_NUMBER;
5267 
5268 	if (dev->isYaffs2) {
5269 		blockIndex = YMALLOC(nBlocks * sizeof(yaffs_BlockIndex));
5270 		if(!blockIndex)
5271 			return YAFFS_FAIL;
5272 	}
5273 
5274 	/* Scan all the blocks to determine their state */
5275 	for (blk = dev->internalStartBlock; blk <= dev->internalEndBlock; blk++) {
5276 		bi = yaffs_GetBlockInfo(dev, blk);
5277 		yaffs_ClearChunkBits(dev, blk);
5278 		bi->pagesInUse = 0;
5279 		bi->softDeletions = 0;
5280 
5281 		yaffs_QueryInitialBlockState(dev, blk, &state, &sequenceNumber);
5282 
5283 		bi->blockState = state;
5284 		bi->sequenceNumber = sequenceNumber;
5285 
5286 		T(YAFFS_TRACE_SCAN_DEBUG,
5287 		  (TSTR("Block scanning block %d state %d seq %d" TENDSTR), blk,
5288 		   state, sequenceNumber));
5289 
5290 		if (state == YAFFS_BLOCK_STATE_DEAD) {
5291 			T(YAFFS_TRACE_BAD_BLOCKS,
5292 			  (TSTR("block %d is bad" TENDSTR), blk));
5293 		} else if (state == YAFFS_BLOCK_STATE_EMPTY) {
5294 			T(YAFFS_TRACE_SCAN_DEBUG,
5295 			  (TSTR("Block empty " TENDSTR)));
5296 			dev->nErasedBlocks++;
5297 			dev->nFreeChunks += dev->nChunksPerBlock;
5298 		} else if (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING) {
5299 
5300 			/* Determine the highest sequence number */
5301 			if (dev->isYaffs2 &&
5302 			    sequenceNumber >= YAFFS_LOWEST_SEQUENCE_NUMBER &&
5303 			    sequenceNumber < YAFFS_HIGHEST_SEQUENCE_NUMBER) {
5304 
5305 				blockIndex[nBlocksToScan].seq = sequenceNumber;
5306 				blockIndex[nBlocksToScan].block = blk;
5307 
5308 				nBlocksToScan++;
5309 
5310 				if (sequenceNumber >= dev->sequenceNumber) {
5311 					dev->sequenceNumber = sequenceNumber;
5312 				}
5313 			} else if (dev->isYaffs2) {
5314 				/* TODO: Nasty sequence number! */
5315 				T(YAFFS_TRACE_SCAN,
5316 				  (TSTR
5317 				   ("Block scanning block %d has bad sequence number %d"
5318 				    TENDSTR), blk, sequenceNumber));
5319 
5320 			}
5321 		}
5322 	}
5323 
5324 	/* Sort the blocks
5325 	 * Dungy old bubble sort for now...
5326 	 */
5327 	if (dev->isYaffs2) {
5328 		yaffs_BlockIndex temp;
5329 		int i;
5330 		int j;
5331 
5332 		for (i = 0; i < nBlocksToScan; i++)
5333 			for (j = i + 1; j < nBlocksToScan; j++)
5334 				if (blockIndex[i].seq > blockIndex[j].seq) {
5335 					temp = blockIndex[j];
5336 					blockIndex[j] = blockIndex[i];
5337 					blockIndex[i] = temp;
5338 				}
5339 	}
5340 
5341 	/* Now scan the blocks looking at the data. */
5342 	if (dev->isYaffs2) {
5343 		startIterator = 0;
5344 		endIterator = nBlocksToScan - 1;
5345 		T(YAFFS_TRACE_SCAN_DEBUG,
5346 		  (TSTR("%d blocks to be scanned" TENDSTR), nBlocksToScan));
5347 	} else {
5348 		startIterator = dev->internalStartBlock;
5349 		endIterator = dev->internalEndBlock;
5350 	}
5351 
5352 	/* For each block.... */
5353 	for (blockIterator = startIterator; !alloc_failed && blockIterator <= endIterator;
5354 	     blockIterator++) {
5355 
5356 		if (dev->isYaffs2) {
5357 			/* get the block to scan in the correct order */
5358 			blk = blockIndex[blockIterator].block;
5359 		} else {
5360 			blk = blockIterator;
5361 		}
5362 
5363 		bi = yaffs_GetBlockInfo(dev, blk);
5364 		state = bi->blockState;
5365 
5366 		deleted = 0;
5367 
5368 		/* For each chunk in each block that needs scanning....*/
5369 		for (c = 0; !alloc_failed && c < dev->nChunksPerBlock &&
5370 		     state == YAFFS_BLOCK_STATE_NEEDS_SCANNING; c++) {
5371 			/* Read the tags and decide what to do */
5372 			chunk = blk * dev->nChunksPerBlock + c;
5373 
5374 			yaffs_ReadChunkWithTagsFromNAND(dev, chunk, NULL,
5375 							&tags);
5376 
5377 			/* Let's have a good look at this chunk... */
5378 
5379 			if (!dev->isYaffs2 && tags.chunkDeleted) {
5380 				/* YAFFS1 only...
5381 				 * A deleted chunk
5382 				 */
5383 				deleted++;
5384 				dev->nFreeChunks++;
5385 				/*T((" %d %d deleted\n",blk,c)); */
5386 			} else if (!tags.chunkUsed) {
5387 				/* An unassigned chunk in the block
5388 				 * This means that either the block is empty or
5389 				 * this is the one being allocated from
5390 				 */
5391 
5392 				if (c == 0) {
5393 					/* We're looking at the first chunk in the block so the block is unused */
5394 					state = YAFFS_BLOCK_STATE_EMPTY;
5395 					dev->nErasedBlocks++;
5396 				} else {
5397 					/* this is the block being allocated from */
5398 					T(YAFFS_TRACE_SCAN,
5399 					  (TSTR
5400 					   (" Allocating from %d %d" TENDSTR),
5401 					   blk, c));
5402 					state = YAFFS_BLOCK_STATE_ALLOCATING;
5403 					dev->allocationBlock = blk;
5404 					dev->allocationPage = c;
5405 					dev->allocationBlockFinder = blk;
5406 					/* Set it to here to encourage the allocator to go forth from here. */
5407 
5408 					/* Yaffs2 sanity check:
5409 					 * This should be the one with the highest sequence number
5410 					 */
5411 					if (dev->isYaffs2
5412 					    && (dev->sequenceNumber !=
5413 						bi->sequenceNumber)) {
5414 						T(YAFFS_TRACE_ALWAYS,
5415 						  (TSTR
5416 						   ("yaffs: Allocation block %d was not highest sequence id:"
5417 						    " block seq = %d, dev seq = %d"
5418 						    TENDSTR), blk,bi->sequenceNumber,dev->sequenceNumber));
5419 					}
5420 				}
5421 
5422 				dev->nFreeChunks += (dev->nChunksPerBlock - c);
5423 			} else if (tags.chunkId > 0) {
5424 				/* chunkId > 0 so it is a data chunk... */
5425 				unsigned int endpos;
5426 
5427 				yaffs_SetChunkBit(dev, blk, c);
5428 				bi->pagesInUse++;
5429 
5430 				in = yaffs_FindOrCreateObjectByNumber(dev,
5431 								      tags.
5432 								      objectId,
5433 								      YAFFS_OBJECT_TYPE_FILE);
5434 				/* PutChunkIntoFile checks for a clash (two data chunks with
5435 				 * the same chunkId).
5436 				 */
5437 
5438 				if(!in)
5439 					alloc_failed = 1;
5440 
5441 				if(in){
5442 					if(!yaffs_PutChunkIntoFile(in, tags.chunkId, chunk,1))
5443 						alloc_failed = 1;
5444 				}
5445 
5446 				endpos =
5447 				    (tags.chunkId - 1) * dev->nDataBytesPerChunk +
5448 				    tags.byteCount;
5449 				if (in &&
5450 				    in->variantType == YAFFS_OBJECT_TYPE_FILE
5451 				    && in->variant.fileVariant.scannedFileSize <
5452 				    endpos) {
5453 					in->variant.fileVariant.
5454 					    scannedFileSize = endpos;
5455 					if (!dev->useHeaderFileSize) {
5456 						in->variant.fileVariant.
5457 						    fileSize =
5458 						    in->variant.fileVariant.
5459 						    scannedFileSize;
5460 					}
5461 
5462 				}
5463 				/* T((" %d %d data %d %d\n",blk,c,tags.objectId,tags.chunkId));   */
5464 			} else {
5465 				/* chunkId == 0, so it is an ObjectHeader.
5466 				 * Thus, we read in the object header and make the object
5467 				 */
5468 				yaffs_SetChunkBit(dev, blk, c);
5469 				bi->pagesInUse++;
5470 
5471 				yaffs_ReadChunkWithTagsFromNAND(dev, chunk,
5472 								chunkData,
5473 								NULL);
5474 
5475 				oh = (yaffs_ObjectHeader *) chunkData;
5476 
5477 				in = yaffs_FindObjectByNumber(dev,
5478 							      tags.objectId);
5479 				if (in && in->variantType != oh->type) {
5480 					/* This should not happen, but somehow
5481 					 * Wev'e ended up with an objectId that has been reused but not yet
5482 					 * deleted, and worse still it has changed type. Delete the old object.
5483 					 */
5484 
5485 					yaffs_DestroyObject(in);
5486 
5487 					in = 0;
5488 				}
5489 
5490 				in = yaffs_FindOrCreateObjectByNumber(dev,
5491 								      tags.
5492 								      objectId,
5493 								      oh->type);
5494 
5495 				if(!in)
5496 					alloc_failed = 1;
5497 
5498 				if (in && oh->shadowsObject > 0) {
5499 					yaffs_HandleShadowedObject(dev,
5500 								   oh->
5501 								   shadowsObject,
5502 								   0);
5503 				}
5504 
5505 				if (in && in->valid) {
5506 					/* We have already filled this one. We have a duplicate and need to resolve it. */
5507 
5508 					unsigned existingSerial = in->serial;
5509 					unsigned newSerial = tags.serialNumber;
5510 
5511 					if (dev->isYaffs2 ||
5512 					    ((existingSerial + 1) & 3) ==
5513 					    newSerial) {
5514 						/* Use new one - destroy the exisiting one */
5515 						yaffs_DeleteChunk(dev,
5516 								  in->chunkId,
5517 								  1, __LINE__);
5518 						in->valid = 0;
5519 					} else {
5520 						/* Use existing - destroy this one. */
5521 						yaffs_DeleteChunk(dev, chunk, 1,
5522 								  __LINE__);
5523 					}
5524 				}
5525 
5526 				if (in && !in->valid &&
5527 				    (tags.objectId == YAFFS_OBJECTID_ROOT ||
5528 				     tags.objectId == YAFFS_OBJECTID_LOSTNFOUND)) {
5529 					/* We only load some info, don't fiddle with directory structure */
5530 					in->valid = 1;
5531 					in->variantType = oh->type;
5532 
5533 					in->yst_mode = oh->yst_mode;
5534 #ifdef CONFIG_YAFFS_WINCE
5535 					in->win_atime[0] = oh->win_atime[0];
5536 					in->win_ctime[0] = oh->win_ctime[0];
5537 					in->win_mtime[0] = oh->win_mtime[0];
5538 					in->win_atime[1] = oh->win_atime[1];
5539 					in->win_ctime[1] = oh->win_ctime[1];
5540 					in->win_mtime[1] = oh->win_mtime[1];
5541 #else
5542 					in->yst_uid = oh->yst_uid;
5543 					in->yst_gid = oh->yst_gid;
5544 					in->yst_atime = oh->yst_atime;
5545 					in->yst_mtime = oh->yst_mtime;
5546 					in->yst_ctime = oh->yst_ctime;
5547 					in->yst_rdev = oh->yst_rdev;
5548 #endif
5549 					in->chunkId = chunk;
5550 
5551 				} else if (in && !in->valid) {
5552 					/* we need to load this info */
5553 
5554 					in->valid = 1;
5555 					in->variantType = oh->type;
5556 
5557 					in->yst_mode = oh->yst_mode;
5558 #ifdef CONFIG_YAFFS_WINCE
5559 					in->win_atime[0] = oh->win_atime[0];
5560 					in->win_ctime[0] = oh->win_ctime[0];
5561 					in->win_mtime[0] = oh->win_mtime[0];
5562 					in->win_atime[1] = oh->win_atime[1];
5563 					in->win_ctime[1] = oh->win_ctime[1];
5564 					in->win_mtime[1] = oh->win_mtime[1];
5565 #else
5566 					in->yst_uid = oh->yst_uid;
5567 					in->yst_gid = oh->yst_gid;
5568 					in->yst_atime = oh->yst_atime;
5569 					in->yst_mtime = oh->yst_mtime;
5570 					in->yst_ctime = oh->yst_ctime;
5571 					in->yst_rdev = oh->yst_rdev;
5572 #endif
5573 					in->chunkId = chunk;
5574 
5575 					yaffs_SetObjectName(in, oh->name);
5576 					in->dirty = 0;
5577 
5578 					/* directory stuff...
5579 					 * hook up to parent
5580 					 */
5581 
5582 					parent =
5583 					    yaffs_FindOrCreateObjectByNumber
5584 					    (dev, oh->parentObjectId,
5585 					     YAFFS_OBJECT_TYPE_DIRECTORY);
5586 					if (parent->variantType ==
5587 					    YAFFS_OBJECT_TYPE_UNKNOWN) {
5588 						/* Set up as a directory */
5589 						parent->variantType =
5590 						    YAFFS_OBJECT_TYPE_DIRECTORY;
5591 						INIT_LIST_HEAD(&parent->variant.
5592 							       directoryVariant.
5593 							       children);
5594 					} else if (parent->variantType !=
5595 						   YAFFS_OBJECT_TYPE_DIRECTORY)
5596 					{
5597 						/* Hoosterman, another problem....
5598 						 * We're trying to use a non-directory as a directory
5599 						 */
5600 
5601 						T(YAFFS_TRACE_ERROR,
5602 						  (TSTR
5603 						   ("yaffs tragedy: attempting to use non-directory as"
5604 						    " a directory in scan. Put in lost+found."
5605 						    TENDSTR)));
5606 						parent = dev->lostNFoundDir;
5607 					}
5608 
5609 					yaffs_AddObjectToDirectory(parent, in);
5610 
5611 					if (0 && (parent == dev->deletedDir ||
5612 						  parent == dev->unlinkedDir)) {
5613 						in->deleted = 1;	/* If it is unlinked at start up then it wants deleting */
5614 						dev->nDeletedFiles++;
5615 					}
5616 					/* Note re hardlinks.
5617 					 * Since we might scan a hardlink before its equivalent object is scanned
5618 					 * we put them all in a list.
5619 					 * After scanning is complete, we should have all the objects, so we run through this
5620 					 * list and fix up all the chains.
5621 					 */
5622 
5623 					switch (in->variantType) {
5624 					case YAFFS_OBJECT_TYPE_UNKNOWN:
5625 						/* Todo got a problem */
5626 						break;
5627 					case YAFFS_OBJECT_TYPE_FILE:
5628 						if (dev->isYaffs2
5629 						    && oh->isShrink) {
5630 							/* Prune back the shrunken chunks */
5631 							yaffs_PruneResizedChunks
5632 							    (in, oh->fileSize);
5633 							/* Mark the block as having a shrinkHeader */
5634 							bi->hasShrinkHeader = 1;
5635 						}
5636 
5637 						if (dev->useHeaderFileSize)
5638 
5639 							in->variant.fileVariant.
5640 							    fileSize =
5641 							    oh->fileSize;
5642 
5643 						break;
5644 					case YAFFS_OBJECT_TYPE_HARDLINK:
5645 						in->variant.hardLinkVariant.
5646 						    equivalentObjectId =
5647 						    oh->equivalentObjectId;
5648 						in->hardLinks.next =
5649 						    (struct list_head *)
5650 						    hardList;
5651 						hardList = in;
5652 						break;
5653 					case YAFFS_OBJECT_TYPE_DIRECTORY:
5654 						/* Do nothing */
5655 						break;
5656 					case YAFFS_OBJECT_TYPE_SPECIAL:
5657 						/* Do nothing */
5658 						break;
5659 					case YAFFS_OBJECT_TYPE_SYMLINK:
5660 						in->variant.symLinkVariant.alias =
5661 						    yaffs_CloneString(oh->alias);
5662 						if(!in->variant.symLinkVariant.alias)
5663 							alloc_failed = 1;
5664 						break;
5665 					}
5666 
5667 					if (parent == dev->deletedDir) {
5668 						yaffs_DestroyObject(in);
5669 						bi->hasShrinkHeader = 1;
5670 					}
5671 				}
5672 			}
5673 		}
5674 
5675 		if (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING) {
5676 			/* If we got this far while scanning, then the block is fully allocated.*/
5677 			state = YAFFS_BLOCK_STATE_FULL;
5678 		}
5679 
5680 		bi->blockState = state;
5681 
5682 		/* Now let's see if it was dirty */
5683 		if (bi->pagesInUse == 0 &&
5684 		    !bi->hasShrinkHeader &&
5685 		    bi->blockState == YAFFS_BLOCK_STATE_FULL) {
5686 			yaffs_BlockBecameDirty(dev, blk);
5687 		}
5688 
5689 	}
5690 
5691 	if (blockIndex) {
5692 		YFREE(blockIndex);
5693 	}
5694 
5695 
5696 	/* Ok, we've done all the scanning.
5697 	 * Fix up the hard link chains.
5698 	 * We should now have scanned all the objects, now it's time to add these
5699 	 * hardlinks.
5700 	 */
5701 
5702 	yaffs_HardlinkFixup(dev,hardList);
5703 
5704 	/* Handle the unlinked files. Since they were left in an unlinked state we should
5705 	 * just delete them.
5706 	 */
5707 	{
5708 		struct list_head *i;
5709 		struct list_head *n;
5710 
5711 		yaffs_Object *l;
5712 		/* Soft delete all the unlinked files */
5713 		list_for_each_safe(i, n,
5714 				   &dev->unlinkedDir->variant.directoryVariant.
5715 				   children) {
5716 			if (i) {
5717 				l = list_entry(i, yaffs_Object, siblings);
5718 				yaffs_DestroyObject(l);
5719 			}
5720 		}
5721 	}
5722 
5723 	yaffs_ReleaseTempBuffer(dev, chunkData, __LINE__);
5724 
5725 	if(alloc_failed){
5726 		return YAFFS_FAIL;
5727 	}
5728 
5729 	T(YAFFS_TRACE_SCAN, (TSTR("yaffs_Scan ends" TENDSTR)));
5730 
5731 
5732 	return YAFFS_OK;
5733 }
5734 
5735 static void yaffs_CheckObjectDetailsLoaded(yaffs_Object *in)
5736 {
5737 	__u8 *chunkData;
5738 	yaffs_ObjectHeader *oh;
5739 	yaffs_Device *dev = in->myDev;
5740 	yaffs_ExtendedTags tags;
5741 
5742 	if(!in)
5743 		return;
5744 
5745 #if 0
5746 	T(YAFFS_TRACE_SCAN,(TSTR("details for object %d %s loaded" TENDSTR),
5747 		in->objectId,
5748 		in->lazyLoaded ? "not yet" : "already"));
5749 #endif
5750 
5751 	if(in->lazyLoaded){
5752 		in->lazyLoaded = 0;
5753 		chunkData = yaffs_GetTempBuffer(dev, __LINE__);
5754 
5755 		yaffs_ReadChunkWithTagsFromNAND(dev, in->chunkId,
5756 						chunkData, &tags);
5757 		oh = (yaffs_ObjectHeader *) chunkData;
5758 
5759 		in->yst_mode = oh->yst_mode;
5760 #ifdef CONFIG_YAFFS_WINCE
5761 		in->win_atime[0] = oh->win_atime[0];
5762 		in->win_ctime[0] = oh->win_ctime[0];
5763 		in->win_mtime[0] = oh->win_mtime[0];
5764 		in->win_atime[1] = oh->win_atime[1];
5765 		in->win_ctime[1] = oh->win_ctime[1];
5766 		in->win_mtime[1] = oh->win_mtime[1];
5767 #else
5768 		in->yst_uid = oh->yst_uid;
5769 		in->yst_gid = oh->yst_gid;
5770 		in->yst_atime = oh->yst_atime;
5771 		in->yst_mtime = oh->yst_mtime;
5772 		in->yst_ctime = oh->yst_ctime;
5773 		in->yst_rdev = oh->yst_rdev;
5774 
5775 #endif
5776 		yaffs_SetObjectName(in, oh->name);
5777 
5778 		if(in->variantType == YAFFS_OBJECT_TYPE_SYMLINK){
5779 			 in->variant.symLinkVariant.alias =
5780 						    yaffs_CloneString(oh->alias);
5781 		}
5782 
5783 		yaffs_ReleaseTempBuffer(dev,chunkData, __LINE__);
5784 	}
5785 }
5786 
5787 static int yaffs_ScanBackwards(yaffs_Device * dev)
5788 {
5789 	yaffs_ExtendedTags tags;
5790 	int blk;
5791 	int blockIterator;
5792 	int startIterator;
5793 	int endIterator;
5794 	int nBlocksToScan = 0;
5795 
5796 	int chunk;
5797 	int c;
5798 	yaffs_BlockState state;
5799 	yaffs_Object *hardList = NULL;
5800 	yaffs_BlockInfo *bi;
5801 	int sequenceNumber;
5802 	yaffs_ObjectHeader *oh;
5803 	yaffs_Object *in;
5804 	yaffs_Object *parent;
5805 	int nBlocks = dev->internalEndBlock - dev->internalStartBlock + 1;
5806 	int itsUnlinked;
5807 	__u8 *chunkData;
5808 
5809 	int fileSize;
5810 	int isShrink;
5811 	int foundChunksInBlock;
5812 	int equivalentObjectId;
5813 	int alloc_failed = 0;
5814 
5815 
5816 	yaffs_BlockIndex *blockIndex = NULL;
5817 	int altBlockIndex = 0;
5818 
5819 	if (!dev->isYaffs2) {
5820 		T(YAFFS_TRACE_SCAN,
5821 		  (TSTR("yaffs_ScanBackwards is only for YAFFS2!" TENDSTR)));
5822 		return YAFFS_FAIL;
5823 	}
5824 
5825 	T(YAFFS_TRACE_SCAN,
5826 	  (TSTR
5827 	   ("yaffs_ScanBackwards starts  intstartblk %d intendblk %d..."
5828 	    TENDSTR), dev->internalStartBlock, dev->internalEndBlock));
5829 
5830 
5831 	dev->sequenceNumber = YAFFS_LOWEST_SEQUENCE_NUMBER;
5832 
5833 	blockIndex = YMALLOC(nBlocks * sizeof(yaffs_BlockIndex));
5834 
5835 	if(!blockIndex) {
5836 		blockIndex = YMALLOC_ALT(nBlocks * sizeof(yaffs_BlockIndex));
5837 		altBlockIndex = 1;
5838 	}
5839 
5840 	if(!blockIndex) {
5841 		T(YAFFS_TRACE_SCAN,
5842 		  (TSTR("yaffs_Scan() could not allocate block index!" TENDSTR)));
5843 		return YAFFS_FAIL;
5844 	}
5845 
5846 	dev->blocksInCheckpoint = 0;
5847 
5848 	chunkData = yaffs_GetTempBuffer(dev, __LINE__);
5849 
5850 	/* Scan all the blocks to determine their state */
5851 	for (blk = dev->internalStartBlock; blk <= dev->internalEndBlock; blk++) {
5852 		bi = yaffs_GetBlockInfo(dev, blk);
5853 		yaffs_ClearChunkBits(dev, blk);
5854 		bi->pagesInUse = 0;
5855 		bi->softDeletions = 0;
5856 
5857 		yaffs_QueryInitialBlockState(dev, blk, &state, &sequenceNumber);
5858 
5859 		bi->blockState = state;
5860 		bi->sequenceNumber = sequenceNumber;
5861 
5862 		if(bi->sequenceNumber == YAFFS_SEQUENCE_CHECKPOINT_DATA)
5863 			bi->blockState = state = YAFFS_BLOCK_STATE_CHECKPOINT;
5864 
5865 		T(YAFFS_TRACE_SCAN_DEBUG,
5866 		  (TSTR("Block scanning block %d state %d seq %d" TENDSTR), blk,
5867 		   state, sequenceNumber));
5868 
5869 
5870 		if(state == YAFFS_BLOCK_STATE_CHECKPOINT){
5871 			dev->blocksInCheckpoint++;
5872 
5873 		} else if (state == YAFFS_BLOCK_STATE_DEAD) {
5874 			T(YAFFS_TRACE_BAD_BLOCKS,
5875 			  (TSTR("block %d is bad" TENDSTR), blk));
5876 		} else if (state == YAFFS_BLOCK_STATE_EMPTY) {
5877 			T(YAFFS_TRACE_SCAN_DEBUG,
5878 			  (TSTR("Block empty " TENDSTR)));
5879 			dev->nErasedBlocks++;
5880 			dev->nFreeChunks += dev->nChunksPerBlock;
5881 		} else if (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING) {
5882 
5883 			/* Determine the highest sequence number */
5884 			if (dev->isYaffs2 &&
5885 			    sequenceNumber >= YAFFS_LOWEST_SEQUENCE_NUMBER &&
5886 			    sequenceNumber < YAFFS_HIGHEST_SEQUENCE_NUMBER) {
5887 
5888 				blockIndex[nBlocksToScan].seq = sequenceNumber;
5889 				blockIndex[nBlocksToScan].block = blk;
5890 
5891 				nBlocksToScan++;
5892 
5893 				if (sequenceNumber >= dev->sequenceNumber) {
5894 					dev->sequenceNumber = sequenceNumber;
5895 				}
5896 			} else if (dev->isYaffs2) {
5897 				/* TODO: Nasty sequence number! */
5898 				T(YAFFS_TRACE_SCAN,
5899 				  (TSTR
5900 				   ("Block scanning block %d has bad sequence number %d"
5901 				    TENDSTR), blk, sequenceNumber));
5902 
5903 			}
5904 		}
5905 	}
5906 
5907 	T(YAFFS_TRACE_SCAN,
5908 	(TSTR("%d blocks to be sorted..." TENDSTR), nBlocksToScan));
5909 
5910 
5911 
5912 	YYIELD();
5913 
5914 	/* Sort the blocks */
5915 #ifndef CONFIG_YAFFS_USE_OWN_SORT
5916 	{
5917 		/* Use qsort now. */
5918 		yaffs_qsort(blockIndex, nBlocksToScan, sizeof(yaffs_BlockIndex), ybicmp);
5919 	}
5920 #else
5921 	{
5922 		/* Dungy old bubble sort... */
5923 
5924 		yaffs_BlockIndex temp;
5925 		int i;
5926 		int j;
5927 
5928 		for (i = 0; i < nBlocksToScan; i++)
5929 			for (j = i + 1; j < nBlocksToScan; j++)
5930 				if (blockIndex[i].seq > blockIndex[j].seq) {
5931 					temp = blockIndex[j];
5932 					blockIndex[j] = blockIndex[i];
5933 					blockIndex[i] = temp;
5934 				}
5935 	}
5936 #endif
5937 
5938 	YYIELD();
5939 
5940 	T(YAFFS_TRACE_SCAN, (TSTR("...done" TENDSTR)));
5941 
5942 	/* Now scan the blocks looking at the data. */
5943 	startIterator = 0;
5944 	endIterator = nBlocksToScan - 1;
5945 	T(YAFFS_TRACE_SCAN_DEBUG,
5946 	  (TSTR("%d blocks to be scanned" TENDSTR), nBlocksToScan));
5947 
5948 	/* For each block.... backwards */
5949 	for (blockIterator = endIterator; !alloc_failed && blockIterator >= startIterator;
5950 	     blockIterator--) {
5951 		/* Cooperative multitasking! This loop can run for so
5952 		   long that watchdog timers expire. */
5953 		YYIELD();
5954 
5955 		/* get the block to scan in the correct order */
5956 		blk = blockIndex[blockIterator].block;
5957 
5958 		bi = yaffs_GetBlockInfo(dev, blk);
5959 
5960 
5961 		state = bi->blockState;
5962 
5963 		/* For each chunk in each block that needs scanning.... */
5964 		foundChunksInBlock = 0;
5965 		for (c = dev->nChunksPerBlock - 1;
5966 		     !alloc_failed && c >= 0 &&
5967 		     (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING ||
5968 		      state == YAFFS_BLOCK_STATE_ALLOCATING); c--) {
5969 			/* Scan backwards...
5970 			 * Read the tags and decide what to do
5971 			 */
5972 
5973 			chunk = blk * dev->nChunksPerBlock + c;
5974 
5975 			yaffs_ReadChunkWithTagsFromNAND(dev, chunk, NULL,
5976 							&tags);
5977 
5978 			/* Let's have a good look at this chunk... */
5979 
5980 			if (!tags.chunkUsed) {
5981 				/* An unassigned chunk in the block.
5982 				 * If there are used chunks after this one, then
5983 				 * it is a chunk that was skipped due to failing the erased
5984 				 * check. Just skip it so that it can be deleted.
5985 				 * But, more typically, We get here when this is an unallocated
5986 				 * chunk and his means that either the block is empty or
5987 				 * this is the one being allocated from
5988 				 */
5989 
5990 				if(foundChunksInBlock)
5991 				{
5992 					/* This is a chunk that was skipped due to failing the erased check */
5993 
5994 				} else if (c == 0) {
5995 					/* We're looking at the first chunk in the block so the block is unused */
5996 					state = YAFFS_BLOCK_STATE_EMPTY;
5997 					dev->nErasedBlocks++;
5998 				} else {
5999 					if (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING ||
6000 					    state == YAFFS_BLOCK_STATE_ALLOCATING) {
6001 						if(dev->sequenceNumber == bi->sequenceNumber) {
6002 							/* this is the block being allocated from */
6003 
6004 							T(YAFFS_TRACE_SCAN,
6005 							  (TSTR
6006 							   (" Allocating from %d %d"
6007 							    TENDSTR), blk, c));
6008 
6009 							state = YAFFS_BLOCK_STATE_ALLOCATING;
6010 							dev->allocationBlock = blk;
6011 							dev->allocationPage = c;
6012 							dev->allocationBlockFinder = blk;
6013 						}
6014 						else {
6015 							/* This is a partially written block that is not
6016 							 * the current allocation block. This block must have
6017 							 * had a write failure, so set up for retirement.
6018 							 */
6019 
6020 							 bi->needsRetiring = 1;
6021 							 bi->gcPrioritise = 1;
6022 
6023 							 T(YAFFS_TRACE_ALWAYS,
6024 							 (TSTR("Partially written block %d being set for retirement" TENDSTR),
6025 							 blk));
6026 						}
6027 
6028 					}
6029 
6030 				}
6031 
6032 				dev->nFreeChunks++;
6033 
6034 			} else if (tags.chunkId > 0) {
6035 				/* chunkId > 0 so it is a data chunk... */
6036 				unsigned int endpos;
6037 				__u32 chunkBase =
6038 				    (tags.chunkId - 1) * dev->nDataBytesPerChunk;
6039 
6040 				foundChunksInBlock = 1;
6041 
6042 
6043 				yaffs_SetChunkBit(dev, blk, c);
6044 				bi->pagesInUse++;
6045 
6046 				in = yaffs_FindOrCreateObjectByNumber(dev,
6047 								      tags.
6048 								      objectId,
6049 								      YAFFS_OBJECT_TYPE_FILE);
6050 				if(!in){
6051 					/* Out of memory */
6052 					alloc_failed = 1;
6053 				}
6054 
6055 				if (in &&
6056 				    in->variantType == YAFFS_OBJECT_TYPE_FILE
6057 				    && chunkBase <
6058 				    in->variant.fileVariant.shrinkSize) {
6059 					/* This has not been invalidated by a resize */
6060 					if(!yaffs_PutChunkIntoFile(in, tags.chunkId,
6061 							       chunk, -1)){
6062 						alloc_failed = 1;
6063 					}
6064 
6065 					/* File size is calculated by looking at the data chunks if we have not
6066 					 * seen an object header yet. Stop this practice once we find an object header.
6067 					 */
6068 					endpos =
6069 					    (tags.chunkId -
6070 					     1) * dev->nDataBytesPerChunk +
6071 					    tags.byteCount;
6072 
6073 					if (!in->valid &&	/* have not got an object header yet */
6074 					    in->variant.fileVariant.
6075 					    scannedFileSize < endpos) {
6076 						in->variant.fileVariant.
6077 						    scannedFileSize = endpos;
6078 						in->variant.fileVariant.
6079 						    fileSize =
6080 						    in->variant.fileVariant.
6081 						    scannedFileSize;
6082 					}
6083 
6084 				} else if(in) {
6085 					/* This chunk has been invalidated by a resize, so delete */
6086 					yaffs_DeleteChunk(dev, chunk, 1, __LINE__);
6087 
6088 				}
6089 			} else {
6090 				/* chunkId == 0, so it is an ObjectHeader.
6091 				 * Thus, we read in the object header and make the object
6092 				 */
6093 				foundChunksInBlock = 1;
6094 
6095 				yaffs_SetChunkBit(dev, blk, c);
6096 				bi->pagesInUse++;
6097 
6098 				oh = NULL;
6099 				in = NULL;
6100 
6101 				if (tags.extraHeaderInfoAvailable) {
6102 					in = yaffs_FindOrCreateObjectByNumber
6103 					    (dev, tags.objectId,
6104 					     tags.extraObjectType);
6105 				}
6106 
6107 				if (!in ||
6108 #ifdef CONFIG_YAFFS_DISABLE_LAZY_LOAD
6109 				    !in->valid ||
6110 #endif
6111 				    tags.extraShadows ||
6112 				    (!in->valid &&
6113 				    (tags.objectId == YAFFS_OBJECTID_ROOT ||
6114 				     tags.objectId == YAFFS_OBJECTID_LOSTNFOUND))
6115 				    ) {
6116 
6117 					/* If we don't have  valid info then we need to read the chunk
6118 					 * TODO In future we can probably defer reading the chunk and
6119 					 * living with invalid data until needed.
6120 					 */
6121 
6122 					yaffs_ReadChunkWithTagsFromNAND(dev,
6123 									chunk,
6124 									chunkData,
6125 									NULL);
6126 
6127 					oh = (yaffs_ObjectHeader *) chunkData;
6128 
6129 					if (!in)
6130 						in = yaffs_FindOrCreateObjectByNumber(dev, tags.objectId, oh->type);
6131 
6132 				}
6133 
6134 				if (!in) {
6135 					/* TODO Hoosterman we have a problem! */
6136 					T(YAFFS_TRACE_ERROR,
6137 					  (TSTR
6138 					   ("yaffs tragedy: Could not make object for object  %d  "
6139 					    "at chunk %d during scan"
6140 					    TENDSTR), tags.objectId, chunk));
6141 
6142 				}
6143 
6144 				if (in->valid) {
6145 					/* We have already filled this one.
6146 					 * We have a duplicate that will be discarded, but
6147 					 * we first have to suck out resize info if it is a file.
6148 					 */
6149 
6150 					if ((in->variantType == YAFFS_OBJECT_TYPE_FILE) &&
6151 					     ((oh &&
6152 					       oh-> type == YAFFS_OBJECT_TYPE_FILE)||
6153 					      (tags.extraHeaderInfoAvailable  &&
6154 					       tags.extraObjectType == YAFFS_OBJECT_TYPE_FILE))
6155 					    ) {
6156 						__u32 thisSize =
6157 						    (oh) ? oh->fileSize : tags.
6158 						    extraFileLength;
6159 						__u32 parentObjectId =
6160 						    (oh) ? oh->
6161 						    parentObjectId : tags.
6162 						    extraParentObjectId;
6163 						unsigned isShrink =
6164 						    (oh) ? oh->isShrink : tags.
6165 						    extraIsShrinkHeader;
6166 
6167 						/* If it is deleted (unlinked at start also means deleted)
6168 						 * we treat the file size as being zeroed at this point.
6169 						 */
6170 						if (parentObjectId ==
6171 						    YAFFS_OBJECTID_DELETED
6172 						    || parentObjectId ==
6173 						    YAFFS_OBJECTID_UNLINKED) {
6174 							thisSize = 0;
6175 							isShrink = 1;
6176 						}
6177 
6178 						if (isShrink &&
6179 						    in->variant.fileVariant.
6180 						    shrinkSize > thisSize) {
6181 							in->variant.fileVariant.
6182 							    shrinkSize =
6183 							    thisSize;
6184 						}
6185 
6186 						if (isShrink) {
6187 							bi->hasShrinkHeader = 1;
6188 						}
6189 
6190 					}
6191 					/* Use existing - destroy this one. */
6192 					yaffs_DeleteChunk(dev, chunk, 1, __LINE__);
6193 
6194 				}
6195 
6196 				if (!in->valid &&
6197 				    (tags.objectId == YAFFS_OBJECTID_ROOT ||
6198 				     tags.objectId ==
6199 				     YAFFS_OBJECTID_LOSTNFOUND)) {
6200 					/* We only load some info, don't fiddle with directory structure */
6201 					in->valid = 1;
6202 
6203 					if(oh) {
6204 						in->variantType = oh->type;
6205 
6206 						in->yst_mode = oh->yst_mode;
6207 #ifdef CONFIG_YAFFS_WINCE
6208 						in->win_atime[0] = oh->win_atime[0];
6209 						in->win_ctime[0] = oh->win_ctime[0];
6210 						in->win_mtime[0] = oh->win_mtime[0];
6211 						in->win_atime[1] = oh->win_atime[1];
6212 						in->win_ctime[1] = oh->win_ctime[1];
6213 						in->win_mtime[1] = oh->win_mtime[1];
6214 #else
6215 						in->yst_uid = oh->yst_uid;
6216 						in->yst_gid = oh->yst_gid;
6217 						in->yst_atime = oh->yst_atime;
6218 						in->yst_mtime = oh->yst_mtime;
6219 						in->yst_ctime = oh->yst_ctime;
6220 						in->yst_rdev = oh->yst_rdev;
6221 
6222 #endif
6223 					} else {
6224 						in->variantType = tags.extraObjectType;
6225 						in->lazyLoaded = 1;
6226 					}
6227 
6228 					in->chunkId = chunk;
6229 
6230 				} else if (!in->valid) {
6231 					/* we need to load this info */
6232 
6233 					in->valid = 1;
6234 					in->chunkId = chunk;
6235 
6236 					if(oh) {
6237 						in->variantType = oh->type;
6238 
6239 						in->yst_mode = oh->yst_mode;
6240 #ifdef CONFIG_YAFFS_WINCE
6241 						in->win_atime[0] = oh->win_atime[0];
6242 						in->win_ctime[0] = oh->win_ctime[0];
6243 						in->win_mtime[0] = oh->win_mtime[0];
6244 						in->win_atime[1] = oh->win_atime[1];
6245 						in->win_ctime[1] = oh->win_ctime[1];
6246 						in->win_mtime[1] = oh->win_mtime[1];
6247 #else
6248 						in->yst_uid = oh->yst_uid;
6249 						in->yst_gid = oh->yst_gid;
6250 						in->yst_atime = oh->yst_atime;
6251 						in->yst_mtime = oh->yst_mtime;
6252 						in->yst_ctime = oh->yst_ctime;
6253 						in->yst_rdev = oh->yst_rdev;
6254 #endif
6255 
6256 						if (oh->shadowsObject > 0)
6257 							yaffs_HandleShadowedObject(dev,
6258 									   oh->
6259 									   shadowsObject,
6260 									   1);
6261 
6262 
6263 						yaffs_SetObjectName(in, oh->name);
6264 						parent =
6265 						    yaffs_FindOrCreateObjectByNumber
6266 							(dev, oh->parentObjectId,
6267 							 YAFFS_OBJECT_TYPE_DIRECTORY);
6268 
6269 						 fileSize = oh->fileSize;
6270 						 isShrink = oh->isShrink;
6271 						 equivalentObjectId = oh->equivalentObjectId;
6272 
6273 					}
6274 					else {
6275 						in->variantType = tags.extraObjectType;
6276 						parent =
6277 						    yaffs_FindOrCreateObjectByNumber
6278 							(dev, tags.extraParentObjectId,
6279 							 YAFFS_OBJECT_TYPE_DIRECTORY);
6280 						 fileSize = tags.extraFileLength;
6281 						 isShrink = tags.extraIsShrinkHeader;
6282 						 equivalentObjectId = tags.extraEquivalentObjectId;
6283 						in->lazyLoaded = 1;
6284 
6285 					}
6286 					in->dirty = 0;
6287 
6288 					/* directory stuff...
6289 					 * hook up to parent
6290 					 */
6291 
6292 					if (parent->variantType ==
6293 					    YAFFS_OBJECT_TYPE_UNKNOWN) {
6294 						/* Set up as a directory */
6295 						parent->variantType =
6296 						    YAFFS_OBJECT_TYPE_DIRECTORY;
6297 						INIT_LIST_HEAD(&parent->variant.
6298 							       directoryVariant.
6299 							       children);
6300 					} else if (parent->variantType !=
6301 						   YAFFS_OBJECT_TYPE_DIRECTORY)
6302 					{
6303 						/* Hoosterman, another problem....
6304 						 * We're trying to use a non-directory as a directory
6305 						 */
6306 
6307 						T(YAFFS_TRACE_ERROR,
6308 						  (TSTR
6309 						   ("yaffs tragedy: attempting to use non-directory as"
6310 						    " a directory in scan. Put in lost+found."
6311 						    TENDSTR)));
6312 						parent = dev->lostNFoundDir;
6313 					}
6314 
6315 					yaffs_AddObjectToDirectory(parent, in);
6316 
6317 					itsUnlinked = (parent == dev->deletedDir) ||
6318 						      (parent == dev->unlinkedDir);
6319 
6320 					if (isShrink) {
6321 						/* Mark the block as having a shrinkHeader */
6322 						bi->hasShrinkHeader = 1;
6323 					}
6324 
6325 					/* Note re hardlinks.
6326 					 * Since we might scan a hardlink before its equivalent object is scanned
6327 					 * we put them all in a list.
6328 					 * After scanning is complete, we should have all the objects, so we run
6329 					 * through this list and fix up all the chains.
6330 					 */
6331 
6332 					switch (in->variantType) {
6333 					case YAFFS_OBJECT_TYPE_UNKNOWN:
6334 						/* Todo got a problem */
6335 						break;
6336 					case YAFFS_OBJECT_TYPE_FILE:
6337 
6338 						if (in->variant.fileVariant.
6339 						    scannedFileSize < fileSize) {
6340 							/* This covers the case where the file size is greater
6341 							 * than where the data is
6342 							 * This will happen if the file is resized to be larger
6343 							 * than its current data extents.
6344 							 */
6345 							in->variant.fileVariant.fileSize = fileSize;
6346 							in->variant.fileVariant.scannedFileSize =
6347 							    in->variant.fileVariant.fileSize;
6348 						}
6349 
6350 						if (isShrink &&
6351 						    in->variant.fileVariant.shrinkSize > fileSize) {
6352 							in->variant.fileVariant.shrinkSize = fileSize;
6353 						}
6354 
6355 						break;
6356 					case YAFFS_OBJECT_TYPE_HARDLINK:
6357 						if(!itsUnlinked) {
6358 						  in->variant.hardLinkVariant.equivalentObjectId =
6359 						    equivalentObjectId;
6360 						  in->hardLinks.next =
6361 						    (struct list_head *) hardList;
6362 						  hardList = in;
6363 						}
6364 						break;
6365 					case YAFFS_OBJECT_TYPE_DIRECTORY:
6366 						/* Do nothing */
6367 						break;
6368 					case YAFFS_OBJECT_TYPE_SPECIAL:
6369 						/* Do nothing */
6370 						break;
6371 					case YAFFS_OBJECT_TYPE_SYMLINK:
6372 						if(oh){
6373 						   in->variant.symLinkVariant.alias =
6374 						    yaffs_CloneString(oh->
6375 								      alias);
6376 						   if(!in->variant.symLinkVariant.alias)
6377 							alloc_failed = 1;
6378 						}
6379 						break;
6380 					}
6381 
6382 				}
6383 
6384 			}
6385 
6386 		} /* End of scanning for each chunk */
6387 
6388 		if (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING) {
6389 			/* If we got this far while scanning, then the block is fully allocated. */
6390 			state = YAFFS_BLOCK_STATE_FULL;
6391 		}
6392 
6393 		bi->blockState = state;
6394 
6395 		/* Now let's see if it was dirty */
6396 		if (bi->pagesInUse == 0 &&
6397 		    !bi->hasShrinkHeader &&
6398 		    bi->blockState == YAFFS_BLOCK_STATE_FULL) {
6399 			yaffs_BlockBecameDirty(dev, blk);
6400 		}
6401 
6402 	}
6403 
6404 	if (altBlockIndex)
6405 		YFREE_ALT(blockIndex);
6406 	else
6407 		YFREE(blockIndex);
6408 
6409 	/* Ok, we've done all the scanning.
6410 	 * Fix up the hard link chains.
6411 	 * We should now have scanned all the objects, now it's time to add these
6412 	 * hardlinks.
6413 	 */
6414 	yaffs_HardlinkFixup(dev,hardList);
6415 
6416 
6417 	/*
6418 	*  Sort out state of unlinked and deleted objects.
6419 	*/
6420 	{
6421 		struct list_head *i;
6422 		struct list_head *n;
6423 
6424 		yaffs_Object *l;
6425 
6426 		/* Soft delete all the unlinked files */
6427 		list_for_each_safe(i, n,
6428 				   &dev->unlinkedDir->variant.directoryVariant.
6429 				   children) {
6430 			if (i) {
6431 				l = list_entry(i, yaffs_Object, siblings);
6432 				yaffs_DestroyObject(l);
6433 			}
6434 		}
6435 
6436 		/* Soft delete all the deletedDir files */
6437 		list_for_each_safe(i, n,
6438 				   &dev->deletedDir->variant.directoryVariant.
6439 				   children) {
6440 			if (i) {
6441 				l = list_entry(i, yaffs_Object, siblings);
6442 				yaffs_DestroyObject(l);
6443 
6444 			}
6445 		}
6446 	}
6447 
6448 	yaffs_ReleaseTempBuffer(dev, chunkData, __LINE__);
6449 
6450 	if(alloc_failed){
6451 		return YAFFS_FAIL;
6452 	}
6453 
6454 	T(YAFFS_TRACE_SCAN, (TSTR("yaffs_ScanBackwards ends" TENDSTR)));
6455 
6456 	return YAFFS_OK;
6457 }
6458 
6459 /*------------------------------  Directory Functions ----------------------------- */
6460 
6461 static void yaffs_RemoveObjectFromDirectory(yaffs_Object * obj)
6462 {
6463 	yaffs_Device *dev = obj->myDev;
6464 
6465 	if(dev && dev->removeObjectCallback)
6466 		dev->removeObjectCallback(obj);
6467 
6468 	list_del_init(&obj->siblings);
6469 	obj->parent = NULL;
6470 }
6471 
6472 
6473 static void yaffs_AddObjectToDirectory(yaffs_Object * directory,
6474 				       yaffs_Object * obj)
6475 {
6476 
6477 	if (!directory) {
6478 		T(YAFFS_TRACE_ALWAYS,
6479 		  (TSTR
6480 		   ("tragedy: Trying to add an object to a null pointer directory"
6481 		    TENDSTR)));
6482 		YBUG();
6483 	}
6484 	if (directory->variantType != YAFFS_OBJECT_TYPE_DIRECTORY) {
6485 		T(YAFFS_TRACE_ALWAYS,
6486 		  (TSTR
6487 		   ("tragedy: Trying to add an object to a non-directory"
6488 		    TENDSTR)));
6489 		YBUG();
6490 	}
6491 
6492 	if (obj->siblings.prev == NULL) {
6493 		/* Not initialised */
6494 		INIT_LIST_HEAD(&obj->siblings);
6495 
6496 	} else if (!list_empty(&obj->siblings)) {
6497 		/* If it is holed up somewhere else, un hook it */
6498 		yaffs_RemoveObjectFromDirectory(obj);
6499 	}
6500 	/* Now add it */
6501 	list_add(&obj->siblings, &directory->variant.directoryVariant.children);
6502 	obj->parent = directory;
6503 
6504 	if (directory == obj->myDev->unlinkedDir
6505 	    || directory == obj->myDev->deletedDir) {
6506 		obj->unlinked = 1;
6507 		obj->myDev->nUnlinkedFiles++;
6508 		obj->renameAllowed = 0;
6509 	}
6510 }
6511 
6512 yaffs_Object *yaffs_FindObjectByName(yaffs_Object * directory,
6513 				     const YCHAR * name)
6514 {
6515 	int sum;
6516 
6517 	struct list_head *i;
6518 	YCHAR buffer[YAFFS_MAX_NAME_LENGTH + 1];
6519 
6520 	yaffs_Object *l;
6521 
6522 	if (!name) {
6523 		return NULL;
6524 	}
6525 
6526 	if (!directory) {
6527 		T(YAFFS_TRACE_ALWAYS,
6528 		  (TSTR
6529 		   ("tragedy: yaffs_FindObjectByName: null pointer directory"
6530 		    TENDSTR)));
6531 		YBUG();
6532 	}
6533 	if (directory->variantType != YAFFS_OBJECT_TYPE_DIRECTORY) {
6534 		T(YAFFS_TRACE_ALWAYS,
6535 		  (TSTR
6536 		   ("tragedy: yaffs_FindObjectByName: non-directory" TENDSTR)));
6537 		YBUG();
6538 	}
6539 
6540 	sum = yaffs_CalcNameSum(name);
6541 
6542 	list_for_each(i, &directory->variant.directoryVariant.children) {
6543 		if (i) {
6544 			l = list_entry(i, yaffs_Object, siblings);
6545 
6546 			yaffs_CheckObjectDetailsLoaded(l);
6547 
6548 			/* Special case for lost-n-found */
6549 			if (l->objectId == YAFFS_OBJECTID_LOSTNFOUND) {
6550 				if (yaffs_strcmp(name, YAFFS_LOSTNFOUND_NAME) == 0) {
6551 					return l;
6552 				}
6553 			} else if (yaffs_SumCompare(l->sum, sum) || l->chunkId <= 0)
6554 			{
6555 				/* LostnFound cunk called Objxxx
6556 				 * Do a real check
6557 				 */
6558 				yaffs_GetObjectName(l, buffer,
6559 						    YAFFS_MAX_NAME_LENGTH);
6560 				if (yaffs_strncmp(name, buffer,YAFFS_MAX_NAME_LENGTH) == 0) {
6561 					return l;
6562 				}
6563 
6564 			}
6565 		}
6566 	}
6567 
6568 	return NULL;
6569 }
6570 
6571 
6572 #if 0
6573 int yaffs_ApplyToDirectoryChildren(yaffs_Object * theDir,
6574 				   int (*fn) (yaffs_Object *))
6575 {
6576 	struct list_head *i;
6577 	yaffs_Object *l;
6578 
6579 	if (!theDir) {
6580 		T(YAFFS_TRACE_ALWAYS,
6581 		  (TSTR
6582 		   ("tragedy: yaffs_FindObjectByName: null pointer directory"
6583 		    TENDSTR)));
6584 		YBUG();
6585 	}
6586 	if (theDir->variantType != YAFFS_OBJECT_TYPE_DIRECTORY) {
6587 		T(YAFFS_TRACE_ALWAYS,
6588 		  (TSTR
6589 		   ("tragedy: yaffs_FindObjectByName: non-directory" TENDSTR)));
6590 		YBUG();
6591 	}
6592 
6593 	list_for_each(i, &theDir->variant.directoryVariant.children) {
6594 		if (i) {
6595 			l = list_entry(i, yaffs_Object, siblings);
6596 			if (l && !fn(l)) {
6597 				return YAFFS_FAIL;
6598 			}
6599 		}
6600 	}
6601 
6602 	return YAFFS_OK;
6603 
6604 }
6605 #endif
6606 
6607 /* GetEquivalentObject dereferences any hard links to get to the
6608  * actual object.
6609  */
6610 
6611 yaffs_Object *yaffs_GetEquivalentObject(yaffs_Object * obj)
6612 {
6613 	if (obj && obj->variantType == YAFFS_OBJECT_TYPE_HARDLINK) {
6614 		/* We want the object id of the equivalent object, not this one */
6615 		obj = obj->variant.hardLinkVariant.equivalentObject;
6616 		yaffs_CheckObjectDetailsLoaded(obj);
6617 	}
6618 	return obj;
6619 
6620 }
6621 
6622 int yaffs_GetObjectName(yaffs_Object * obj, YCHAR * name, int buffSize)
6623 {
6624 	memset(name, 0, buffSize * sizeof(YCHAR));
6625 
6626 	yaffs_CheckObjectDetailsLoaded(obj);
6627 
6628 	if (obj->objectId == YAFFS_OBJECTID_LOSTNFOUND) {
6629 		yaffs_strncpy(name, YAFFS_LOSTNFOUND_NAME, buffSize - 1);
6630 	} else if (obj->chunkId <= 0) {
6631 		YCHAR locName[20];
6632 		/* make up a name */
6633 		yaffs_sprintf(locName, _Y("%s%d"), YAFFS_LOSTNFOUND_PREFIX,
6634 			      obj->objectId);
6635 		yaffs_strncpy(name, locName, buffSize - 1);
6636 
6637 	}
6638 #ifdef CONFIG_YAFFS_SHORT_NAMES_IN_RAM
6639 	else if (obj->shortName[0]) {
6640 		yaffs_strcpy(name, obj->shortName);
6641 	}
6642 #endif
6643 	else {
6644 		__u8 *buffer = yaffs_GetTempBuffer(obj->myDev, __LINE__);
6645 
6646 		yaffs_ObjectHeader *oh = (yaffs_ObjectHeader *) buffer;
6647 
6648 		memset(buffer, 0, obj->myDev->nDataBytesPerChunk);
6649 
6650 		if (obj->chunkId >= 0) {
6651 			yaffs_ReadChunkWithTagsFromNAND(obj->myDev,
6652 							obj->chunkId, buffer,
6653 							NULL);
6654 		}
6655 		yaffs_strncpy(name, oh->name, buffSize - 1);
6656 
6657 		yaffs_ReleaseTempBuffer(obj->myDev, buffer, __LINE__);
6658 	}
6659 
6660 	return yaffs_strlen(name);
6661 }
6662 
6663 int yaffs_GetObjectFileLength(yaffs_Object * obj)
6664 {
6665 
6666 	/* Dereference any hard linking */
6667 	obj = yaffs_GetEquivalentObject(obj);
6668 
6669 	if (obj->variantType == YAFFS_OBJECT_TYPE_FILE) {
6670 		return obj->variant.fileVariant.fileSize;
6671 	}
6672 	if (obj->variantType == YAFFS_OBJECT_TYPE_SYMLINK) {
6673 		return yaffs_strlen(obj->variant.symLinkVariant.alias);
6674 	} else {
6675 		/* Only a directory should drop through to here */
6676 		return obj->myDev->nDataBytesPerChunk;
6677 	}
6678 }
6679 
6680 int yaffs_GetObjectLinkCount(yaffs_Object * obj)
6681 {
6682 	int count = 0;
6683 	struct list_head *i;
6684 
6685 	if (!obj->unlinked) {
6686 		count++;	/* the object itself */
6687 	}
6688 	list_for_each(i, &obj->hardLinks) {
6689 		count++;	/* add the hard links; */
6690 	}
6691 	return count;
6692 
6693 }
6694 
6695 int yaffs_GetObjectInode(yaffs_Object * obj)
6696 {
6697 	obj = yaffs_GetEquivalentObject(obj);
6698 
6699 	return obj->objectId;
6700 }
6701 
6702 unsigned yaffs_GetObjectType(yaffs_Object * obj)
6703 {
6704 	obj = yaffs_GetEquivalentObject(obj);
6705 
6706 	switch (obj->variantType) {
6707 	case YAFFS_OBJECT_TYPE_FILE:
6708 		return DT_REG;
6709 		break;
6710 	case YAFFS_OBJECT_TYPE_DIRECTORY:
6711 		return DT_DIR;
6712 		break;
6713 	case YAFFS_OBJECT_TYPE_SYMLINK:
6714 		return DT_LNK;
6715 		break;
6716 	case YAFFS_OBJECT_TYPE_HARDLINK:
6717 		return DT_REG;
6718 		break;
6719 	case YAFFS_OBJECT_TYPE_SPECIAL:
6720 		if (S_ISFIFO(obj->yst_mode))
6721 			return DT_FIFO;
6722 		if (S_ISCHR(obj->yst_mode))
6723 			return DT_CHR;
6724 		if (S_ISBLK(obj->yst_mode))
6725 			return DT_BLK;
6726 		if (S_ISSOCK(obj->yst_mode))
6727 			return DT_SOCK;
6728 	default:
6729 		return DT_REG;
6730 		break;
6731 	}
6732 }
6733 
6734 YCHAR *yaffs_GetSymlinkAlias(yaffs_Object * obj)
6735 {
6736 	obj = yaffs_GetEquivalentObject(obj);
6737 	if (obj->variantType == YAFFS_OBJECT_TYPE_SYMLINK) {
6738 		return yaffs_CloneString(obj->variant.symLinkVariant.alias);
6739 	} else {
6740 		return yaffs_CloneString(_Y(""));
6741 	}
6742 }
6743 
6744 #ifndef CONFIG_YAFFS_WINCE
6745 
6746 int yaffs_SetAttributes(yaffs_Object * obj, struct iattr *attr)
6747 {
6748 	unsigned int valid = attr->ia_valid;
6749 
6750 	if (valid & ATTR_MODE)
6751 		obj->yst_mode = attr->ia_mode;
6752 	if (valid & ATTR_UID)
6753 		obj->yst_uid = attr->ia_uid;
6754 	if (valid & ATTR_GID)
6755 		obj->yst_gid = attr->ia_gid;
6756 
6757 	if (valid & ATTR_ATIME)
6758 		obj->yst_atime = Y_TIME_CONVERT(attr->ia_atime);
6759 	if (valid & ATTR_CTIME)
6760 		obj->yst_ctime = Y_TIME_CONVERT(attr->ia_ctime);
6761 	if (valid & ATTR_MTIME)
6762 		obj->yst_mtime = Y_TIME_CONVERT(attr->ia_mtime);
6763 
6764 	if (valid & ATTR_SIZE)
6765 		yaffs_ResizeFile(obj, attr->ia_size);
6766 
6767 	yaffs_UpdateObjectHeader(obj, NULL, 1, 0, 0);
6768 
6769 	return YAFFS_OK;
6770 
6771 }
6772 int yaffs_GetAttributes(yaffs_Object * obj, struct iattr *attr)
6773 {
6774 	unsigned int valid = 0;
6775 
6776 	attr->ia_mode = obj->yst_mode;
6777 	valid |= ATTR_MODE;
6778 	attr->ia_uid = obj->yst_uid;
6779 	valid |= ATTR_UID;
6780 	attr->ia_gid = obj->yst_gid;
6781 	valid |= ATTR_GID;
6782 
6783 	Y_TIME_CONVERT(attr->ia_atime) = obj->yst_atime;
6784 	valid |= ATTR_ATIME;
6785 	Y_TIME_CONVERT(attr->ia_ctime) = obj->yst_ctime;
6786 	valid |= ATTR_CTIME;
6787 	Y_TIME_CONVERT(attr->ia_mtime) = obj->yst_mtime;
6788 	valid |= ATTR_MTIME;
6789 
6790 	attr->ia_size = yaffs_GetFileSize(obj);
6791 	valid |= ATTR_SIZE;
6792 
6793 	attr->ia_valid = valid;
6794 
6795 	return YAFFS_OK;
6796 
6797 }
6798 
6799 #endif
6800 
6801 #if 0
6802 int yaffs_DumpObject(yaffs_Object * obj)
6803 {
6804 	YCHAR name[257];
6805 
6806 	yaffs_GetObjectName(obj, name, 256);
6807 
6808 	T(YAFFS_TRACE_ALWAYS,
6809 	  (TSTR
6810 	   ("Object %d, inode %d \"%s\"\n dirty %d valid %d serial %d sum %d"
6811 	    " chunk %d type %d size %d\n"
6812 	    TENDSTR), obj->objectId, yaffs_GetObjectInode(obj), name,
6813 	   obj->dirty, obj->valid, obj->serial, obj->sum, obj->chunkId,
6814 	   yaffs_GetObjectType(obj), yaffs_GetObjectFileLength(obj)));
6815 
6816 	return YAFFS_OK;
6817 }
6818 #endif
6819 
6820 /*---------------------------- Initialisation code -------------------------------------- */
6821 
6822 static int yaffs_CheckDevFunctions(const yaffs_Device * dev)
6823 {
6824 
6825 	/* Common functions, gotta have */
6826 	if (!dev->eraseBlockInNAND || !dev->initialiseNAND)
6827 		return 0;
6828 
6829 #ifdef CONFIG_YAFFS_YAFFS2
6830 
6831 	/* Can use the "with tags" style interface for yaffs1 or yaffs2 */
6832 	if (dev->writeChunkWithTagsToNAND &&
6833 	    dev->readChunkWithTagsFromNAND &&
6834 	    !dev->writeChunkToNAND &&
6835 	    !dev->readChunkFromNAND &&
6836 	    dev->markNANDBlockBad && dev->queryNANDBlock)
6837 		return 1;
6838 #endif
6839 
6840 	/* Can use the "spare" style interface for yaffs1 */
6841 	if (!dev->isYaffs2 &&
6842 	    !dev->writeChunkWithTagsToNAND &&
6843 	    !dev->readChunkWithTagsFromNAND &&
6844 	    dev->writeChunkToNAND &&
6845 	    dev->readChunkFromNAND &&
6846 	    !dev->markNANDBlockBad && !dev->queryNANDBlock)
6847 		return 1;
6848 
6849 	return 0;		/* bad */
6850 }
6851 
6852 
6853 static int yaffs_CreateInitialDirectories(yaffs_Device *dev)
6854 {
6855 	/* Initialise the unlinked, deleted, root and lost and found directories */
6856 
6857 	dev->lostNFoundDir = dev->rootDir =  NULL;
6858 	dev->unlinkedDir = dev->deletedDir = NULL;
6859 
6860 	dev->unlinkedDir =
6861 	    yaffs_CreateFakeDirectory(dev, YAFFS_OBJECTID_UNLINKED, S_IFDIR);
6862 
6863 	dev->deletedDir =
6864 	    yaffs_CreateFakeDirectory(dev, YAFFS_OBJECTID_DELETED, S_IFDIR);
6865 
6866 	dev->rootDir =
6867 	    yaffs_CreateFakeDirectory(dev, YAFFS_OBJECTID_ROOT,
6868 				      YAFFS_ROOT_MODE | S_IFDIR);
6869 	dev->lostNFoundDir =
6870 	    yaffs_CreateFakeDirectory(dev, YAFFS_OBJECTID_LOSTNFOUND,
6871 				      YAFFS_LOSTNFOUND_MODE | S_IFDIR);
6872 
6873 	if(dev->lostNFoundDir && dev->rootDir && dev->unlinkedDir && dev->deletedDir){
6874 		yaffs_AddObjectToDirectory(dev->rootDir, dev->lostNFoundDir);
6875 		return YAFFS_OK;
6876 	}
6877 
6878 	return YAFFS_FAIL;
6879 }
6880 
6881 int yaffs_GutsInitialise(yaffs_Device * dev)
6882 {
6883 	int init_failed = 0;
6884 	unsigned x;
6885 	int bits;
6886 
6887 	T(YAFFS_TRACE_TRACING, (TSTR("yaffs: yaffs_GutsInitialise()" TENDSTR)));
6888 
6889 	/* Check stuff that must be set */
6890 
6891 	if (!dev) {
6892 		T(YAFFS_TRACE_ALWAYS, (TSTR("yaffs: Need a device" TENDSTR)));
6893 		return YAFFS_FAIL;
6894 	}
6895 
6896 	dev->internalStartBlock = dev->startBlock;
6897 	dev->internalEndBlock = dev->endBlock;
6898 	dev->blockOffset = 0;
6899 	dev->chunkOffset = 0;
6900 	dev->nFreeChunks = 0;
6901 
6902 	if (dev->startBlock == 0) {
6903 		dev->internalStartBlock = dev->startBlock + 1;
6904 		dev->internalEndBlock = dev->endBlock + 1;
6905 		dev->blockOffset = 1;
6906 		dev->chunkOffset = dev->nChunksPerBlock;
6907 	}
6908 
6909 	/* Check geometry parameters. */
6910 
6911 	if ((dev->isYaffs2 && dev->nDataBytesPerChunk < 1024) ||
6912 	    (!dev->isYaffs2 && dev->nDataBytesPerChunk != 512) ||
6913 	     dev->nChunksPerBlock < 2 ||
6914 	     dev->nReservedBlocks < 2 ||
6915 	     dev->internalStartBlock <= 0 ||
6916 	     dev->internalEndBlock <= 0 ||
6917 	     dev->internalEndBlock <= (dev->internalStartBlock + dev->nReservedBlocks + 2)	// otherwise it is too small
6918 	    ) {
6919 		T(YAFFS_TRACE_ALWAYS,
6920 		  (TSTR
6921 		   ("yaffs: NAND geometry problems: chunk size %d, type is yaffs%s "
6922 		    TENDSTR), dev->nDataBytesPerChunk, dev->isYaffs2 ? "2" : ""));
6923 		return YAFFS_FAIL;
6924 	}
6925 
6926 	if (yaffs_InitialiseNAND(dev) != YAFFS_OK) {
6927 		T(YAFFS_TRACE_ALWAYS,
6928 		  (TSTR("yaffs: InitialiseNAND failed" TENDSTR)));
6929 		return YAFFS_FAIL;
6930 	}
6931 
6932 	/* Got the right mix of functions? */
6933 	if (!yaffs_CheckDevFunctions(dev)) {
6934 		/* Function missing */
6935 		T(YAFFS_TRACE_ALWAYS,
6936 		  (TSTR
6937 		   ("yaffs: device function(s) missing or wrong\n" TENDSTR)));
6938 
6939 		return YAFFS_FAIL;
6940 	}
6941 
6942 	/* This is really a compilation check. */
6943 	if (!yaffs_CheckStructures()) {
6944 		T(YAFFS_TRACE_ALWAYS,
6945 		  (TSTR("yaffs_CheckStructures failed\n" TENDSTR)));
6946 		return YAFFS_FAIL;
6947 	}
6948 
6949 	if (dev->isMounted) {
6950 		T(YAFFS_TRACE_ALWAYS,
6951 		  (TSTR("yaffs: device already mounted\n" TENDSTR)));
6952 		return YAFFS_FAIL;
6953 	}
6954 
6955 	/* Finished with most checks. One or two more checks happen later on too. */
6956 
6957 	dev->isMounted = 1;
6958 
6959 
6960 
6961 	/* OK now calculate a few things for the device */
6962 
6963 	/*
6964 	 *  Calculate all the chunk size manipulation numbers:
6965 	 */
6966 	 /* Start off assuming it is a power of 2 */
6967 	 dev->chunkShift = ShiftDiv(dev->nDataBytesPerChunk);
6968 	 dev->chunkMask = (1<<dev->chunkShift) - 1;
6969 
6970 	 if(dev->nDataBytesPerChunk == (dev->chunkMask + 1)){
6971 		/* Yes it is a power of 2, disable crumbs */
6972 		dev->crumbMask = 0;
6973 		dev->crumbShift = 0;
6974 		dev->crumbsPerChunk = 0;
6975 	 } else {
6976 		/* Not a power of 2, use crumbs instead */
6977 		dev->crumbShift = ShiftDiv(sizeof(yaffs_PackedTags2TagsPart));
6978 		dev->crumbMask = (1<<dev->crumbShift)-1;
6979 		dev->crumbsPerChunk = dev->nDataBytesPerChunk/(1 << dev->crumbShift);
6980 		dev->chunkShift = 0;
6981 		dev->chunkMask = 0;
6982 	}
6983 
6984 
6985 	/*
6986 	 * Calculate chunkGroupBits.
6987 	 * We need to find the next power of 2 > than internalEndBlock
6988 	 */
6989 
6990 	x = dev->nChunksPerBlock * (dev->internalEndBlock + 1);
6991 
6992 	bits = ShiftsGE(x);
6993 
6994 	/* Set up tnode width if wide tnodes are enabled. */
6995 	if(!dev->wideTnodesDisabled){
6996 		/* bits must be even so that we end up with 32-bit words */
6997 		if(bits & 1)
6998 			bits++;
6999 		if(bits < 16)
7000 			dev->tnodeWidth = 16;
7001 		else
7002 			dev->tnodeWidth = bits;
7003 	}
7004 	else
7005 		dev->tnodeWidth = 16;
7006 
7007 	dev->tnodeMask = (1<<dev->tnodeWidth)-1;
7008 
7009 	/* Level0 Tnodes are 16 bits or wider (if wide tnodes are enabled),
7010 	 * so if the bitwidth of the
7011 	 * chunk range we're using is greater than 16 we need
7012 	 * to figure out chunk shift and chunkGroupSize
7013 	 */
7014 
7015 	if (bits <= dev->tnodeWidth)
7016 		dev->chunkGroupBits = 0;
7017 	else
7018 		dev->chunkGroupBits = bits - dev->tnodeWidth;
7019 
7020 
7021 	dev->chunkGroupSize = 1 << dev->chunkGroupBits;
7022 
7023 	if (dev->nChunksPerBlock < dev->chunkGroupSize) {
7024 		/* We have a problem because the soft delete won't work if
7025 		 * the chunk group size > chunks per block.
7026 		 * This can be remedied by using larger "virtual blocks".
7027 		 */
7028 		T(YAFFS_TRACE_ALWAYS,
7029 		  (TSTR("yaffs: chunk group too large\n" TENDSTR)));
7030 
7031 		return YAFFS_FAIL;
7032 	}
7033 
7034 	/* OK, we've finished verifying the device, lets continue with initialisation */
7035 
7036 	/* More device initialisation */
7037 	dev->garbageCollections = 0;
7038 	dev->passiveGarbageCollections = 0;
7039 	dev->currentDirtyChecker = 0;
7040 	dev->bufferedBlock = -1;
7041 	dev->doingBufferedBlockRewrite = 0;
7042 	dev->nDeletedFiles = 0;
7043 	dev->nBackgroundDeletions = 0;
7044 	dev->nUnlinkedFiles = 0;
7045 	dev->eccFixed = 0;
7046 	dev->eccUnfixed = 0;
7047 	dev->tagsEccFixed = 0;
7048 	dev->tagsEccUnfixed = 0;
7049 	dev->nErasureFailures = 0;
7050 	dev->nErasedBlocks = 0;
7051 	dev->isDoingGC = 0;
7052 	dev->hasPendingPrioritisedGCs = 1; /* Assume the worst for now, will get fixed on first GC */
7053 
7054 	/* Initialise temporary buffers and caches. */
7055 	if(!yaffs_InitialiseTempBuffers(dev))
7056 		init_failed = 1;
7057 
7058 	dev->srCache = NULL;
7059 	dev->gcCleanupList = NULL;
7060 
7061 
7062 	if (!init_failed &&
7063 	    dev->nShortOpCaches > 0) {
7064 		int i;
7065 		__u8 *buf;
7066 		int srCacheBytes = dev->nShortOpCaches * sizeof(yaffs_ChunkCache);
7067 
7068 		if (dev->nShortOpCaches > YAFFS_MAX_SHORT_OP_CACHES) {
7069 			dev->nShortOpCaches = YAFFS_MAX_SHORT_OP_CACHES;
7070 		}
7071 
7072 		dev->srCache = YMALLOC(srCacheBytes);
7073 		buf = (__u8 *)dev->srCache;
7074 
7075 		if(dev->srCache)
7076 			memset(dev->srCache,0,srCacheBytes);
7077 
7078 		for (i = 0; i < dev->nShortOpCaches && buf; i++) {
7079 			dev->srCache[i].object = NULL;
7080 			dev->srCache[i].lastUse = 0;
7081 			dev->srCache[i].dirty = 0;
7082 			dev->srCache[i].data = buf = YMALLOC_DMA(dev->nDataBytesPerChunk);
7083 		}
7084 		if(!buf)
7085 			init_failed = 1;
7086 
7087 		dev->srLastUse = 0;
7088 	}
7089 
7090 	dev->cacheHits = 0;
7091 
7092 	if(!init_failed){
7093 		dev->gcCleanupList = YMALLOC(dev->nChunksPerBlock * sizeof(__u32));
7094 		if(!dev->gcCleanupList)
7095 			init_failed = 1;
7096 	}
7097 
7098 	if (dev->isYaffs2) {
7099 		dev->useHeaderFileSize = 1;
7100 	}
7101 	if(!init_failed && !yaffs_InitialiseBlocks(dev))
7102 		init_failed = 1;
7103 
7104 	yaffs_InitialiseTnodes(dev);
7105 	yaffs_InitialiseObjects(dev);
7106 
7107 	if(!init_failed && !yaffs_CreateInitialDirectories(dev))
7108 		init_failed = 1;
7109 
7110 
7111 	if(!init_failed){
7112 		/* Now scan the flash. */
7113 		if (dev->isYaffs2) {
7114 			if(yaffs_CheckpointRestore(dev)) {
7115 				T(YAFFS_TRACE_ALWAYS,
7116 				  (TSTR("yaffs: restored from checkpoint" TENDSTR)));
7117 			} else {
7118 
7119 				/* Clean up the mess caused by an aborted checkpoint load
7120 				 * and scan backwards.
7121 				 */
7122 				yaffs_DeinitialiseBlocks(dev);
7123 				yaffs_DeinitialiseTnodes(dev);
7124 				yaffs_DeinitialiseObjects(dev);
7125 
7126 
7127 				dev->nErasedBlocks = 0;
7128 				dev->nFreeChunks = 0;
7129 				dev->allocationBlock = -1;
7130 				dev->allocationPage = -1;
7131 				dev->nDeletedFiles = 0;
7132 				dev->nUnlinkedFiles = 0;
7133 				dev->nBackgroundDeletions = 0;
7134 				dev->oldestDirtySequence = 0;
7135 
7136 				if(!init_failed && !yaffs_InitialiseBlocks(dev))
7137 					init_failed = 1;
7138 
7139 				yaffs_InitialiseTnodes(dev);
7140 				yaffs_InitialiseObjects(dev);
7141 
7142 				if(!init_failed && !yaffs_CreateInitialDirectories(dev))
7143 					init_failed = 1;
7144 
7145 				if(!init_failed && !yaffs_ScanBackwards(dev))
7146 					init_failed = 1;
7147 			}
7148 		}else
7149 			if(!yaffs_Scan(dev))
7150 				init_failed = 1;
7151 	}
7152 
7153 	if(init_failed){
7154 		/* Clean up the mess */
7155 		T(YAFFS_TRACE_TRACING,
7156 		  (TSTR("yaffs: yaffs_GutsInitialise() aborted.\n" TENDSTR)));
7157 
7158 		yaffs_Deinitialise(dev);
7159 		return YAFFS_FAIL;
7160 	}
7161 
7162 	/* Zero out stats */
7163 	dev->nPageReads = 0;
7164 	dev->nPageWrites = 0;
7165 	dev->nBlockErasures = 0;
7166 	dev->nGCCopies = 0;
7167 	dev->nRetriedWrites = 0;
7168 
7169 	dev->nRetiredBlocks = 0;
7170 
7171 	yaffs_VerifyFreeChunks(dev);
7172 	yaffs_VerifyBlocks(dev);
7173 
7174 
7175 	T(YAFFS_TRACE_TRACING,
7176 	  (TSTR("yaffs: yaffs_GutsInitialise() done.\n" TENDSTR)));
7177 	return YAFFS_OK;
7178 
7179 }
7180 
7181 void yaffs_Deinitialise(yaffs_Device * dev)
7182 {
7183 	if (dev->isMounted) {
7184 		int i;
7185 
7186 		yaffs_DeinitialiseBlocks(dev);
7187 		yaffs_DeinitialiseTnodes(dev);
7188 		yaffs_DeinitialiseObjects(dev);
7189 		if (dev->nShortOpCaches > 0 &&
7190 		    dev->srCache) {
7191 
7192 			for (i = 0; i < dev->nShortOpCaches; i++) {
7193 				if(dev->srCache[i].data)
7194 					YFREE(dev->srCache[i].data);
7195 				dev->srCache[i].data = NULL;
7196 			}
7197 
7198 			YFREE(dev->srCache);
7199 			dev->srCache = NULL;
7200 		}
7201 
7202 		YFREE(dev->gcCleanupList);
7203 
7204 		for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
7205 			YFREE(dev->tempBuffer[i].buffer);
7206 		}
7207 
7208 		dev->isMounted = 0;
7209 	}
7210 
7211 }
7212 
7213 static int yaffs_CountFreeChunks(yaffs_Device * dev)
7214 {
7215 	int nFree;
7216 	int b;
7217 
7218 	yaffs_BlockInfo *blk;
7219 
7220 	for (nFree = 0, b = dev->internalStartBlock; b <= dev->internalEndBlock;
7221 	     b++) {
7222 		blk = yaffs_GetBlockInfo(dev, b);
7223 
7224 		switch (blk->blockState) {
7225 		case YAFFS_BLOCK_STATE_EMPTY:
7226 		case YAFFS_BLOCK_STATE_ALLOCATING:
7227 		case YAFFS_BLOCK_STATE_COLLECTING:
7228 		case YAFFS_BLOCK_STATE_FULL:
7229 			nFree +=
7230 			    (dev->nChunksPerBlock - blk->pagesInUse +
7231 			     blk->softDeletions);
7232 			break;
7233 		default:
7234 			break;
7235 		}
7236 
7237 	}
7238 
7239 	return nFree;
7240 }
7241 
7242 int yaffs_GetNumberOfFreeChunks(yaffs_Device * dev)
7243 {
7244 	/* This is what we report to the outside world */
7245 
7246 	int nFree;
7247 	int nDirtyCacheChunks;
7248 	int blocksForCheckpoint;
7249 
7250 #if 1
7251 	nFree = dev->nFreeChunks;
7252 #else
7253 	nFree = yaffs_CountFreeChunks(dev);
7254 #endif
7255 
7256 	nFree += dev->nDeletedFiles;
7257 
7258 	/* Now count the number of dirty chunks in the cache and subtract those */
7259 
7260 	{
7261 		int i;
7262 		for (nDirtyCacheChunks = 0, i = 0; i < dev->nShortOpCaches; i++) {
7263 			if (dev->srCache[i].dirty)
7264 				nDirtyCacheChunks++;
7265 		}
7266 	}
7267 
7268 	nFree -= nDirtyCacheChunks;
7269 
7270 	nFree -= ((dev->nReservedBlocks + 1) * dev->nChunksPerBlock);
7271 
7272 	/* Now we figure out how much to reserve for the checkpoint and report that... */
7273 	blocksForCheckpoint = dev->nCheckpointReservedBlocks - dev->blocksInCheckpoint;
7274 	if(blocksForCheckpoint < 0)
7275 		blocksForCheckpoint = 0;
7276 
7277 	nFree -= (blocksForCheckpoint * dev->nChunksPerBlock);
7278 
7279 	if (nFree < 0)
7280 		nFree = 0;
7281 
7282 	return nFree;
7283 
7284 }
7285 
7286 static int yaffs_freeVerificationFailures;
7287 
7288 static void yaffs_VerifyFreeChunks(yaffs_Device * dev)
7289 {
7290 	int counted;
7291 	int difference;
7292 
7293 	if(yaffs_SkipVerification(dev))
7294 		return;
7295 
7296 	counted = yaffs_CountFreeChunks(dev);
7297 
7298 	difference = dev->nFreeChunks - counted;
7299 
7300 	if (difference) {
7301 		T(YAFFS_TRACE_ALWAYS,
7302 		  (TSTR("Freechunks verification failure %d %d %d" TENDSTR),
7303 		   dev->nFreeChunks, counted, difference));
7304 		yaffs_freeVerificationFailures++;
7305 	}
7306 }
7307 
7308 /*---------------------------------------- YAFFS test code ----------------------*/
7309 
7310 #define yaffs_CheckStruct(structure,syze, name) \
7311 	   if(sizeof(structure) != syze) \
7312 	       { \
7313 		 T(YAFFS_TRACE_ALWAYS,(TSTR("%s should be %d but is %d\n" TENDSTR),\
7314 		 name,syze,sizeof(structure))); \
7315 		 return YAFFS_FAIL; \
7316 		}
7317 
7318 static int yaffs_CheckStructures(void)
7319 {
7320 /*      yaffs_CheckStruct(yaffs_Tags,8,"yaffs_Tags") */
7321 /*      yaffs_CheckStruct(yaffs_TagsUnion,8,"yaffs_TagsUnion") */
7322 /*      yaffs_CheckStruct(yaffs_Spare,16,"yaffs_Spare") */
7323 #ifndef CONFIG_YAFFS_TNODE_LIST_DEBUG
7324 	yaffs_CheckStruct(yaffs_Tnode, 2 * YAFFS_NTNODES_LEVEL0, "yaffs_Tnode")
7325 #endif
7326 	    yaffs_CheckStruct(yaffs_ObjectHeader, 512, "yaffs_ObjectHeader")
7327 
7328 	    return YAFFS_OK;
7329 }
7330