Add stuff for object shadowing and fix a constness
[yaffs2.git] / yaffs_guts.c
1 /*
2  * YAFFS: Yet another FFS. A NAND-flash specific file system. 
3  *
4  * Copyright (C) 2002 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  //yaffs_guts.c
15
16 const char *yaffs_guts_c_version="$Id: yaffs_guts.c,v 1.11 2005-07-27 02:00:48 charles Exp $";
17
18 #include "yportenv.h"
19
20 #include "yaffsinterface.h"
21 #include "yaffs_guts.h"
22 #include "yaffs_tagsvalidity.h"
23
24
25 #include "yaffs_tagscompat.h"
26
27 #ifdef CONFIG_YAFFS_WINCE
28 void yfsd_LockYAFFS(BOOL fsLockOnly);
29 void yfsd_UnlockYAFFS(BOOL fsLockOnly);
30 #endif
31
32 #define YAFFS_PASSIVE_GC_CHUNKS 2
33
34 #if 0
35 // Use Steven Hill's ECC struff instead
36 // External functions for ECC on data
37 void nand_calculate_ecc (const u_char *dat, u_char *ecc_code);
38 int nand_correct_data (u_char *dat, u_char *read_ecc, u_char *calc_ecc);
39 #define yaffs_ECCCalculate(data,ecc) nand_calculate_ecc(data,ecc)
40 #define yaffs_ECCCorrect(data,read_ecc,calc_ecc) nand_correct_ecc(data,read_ecc,calc_ecc)
41 #else
42 #include "yaffs_ecc.h"
43 #endif
44
45 #if 0
46 // countBits is a quick way of counting the number of bits in a byte.
47 // ie. countBits[n] holds the number of 1 bits in a byte with the value n.
48
49 static const char yaffs_countBitsTable[256] =
50 {
51 0,1,1,2,1,2,2,3,1,2,2,3,2,3,3,4,
52 1,2,2,3,2,3,3,4,2,3,3,4,3,4,4,5,
53 1,2,2,3,2,3,3,4,2,3,3,4,3,4,4,5,
54 2,3,3,4,3,4,4,5,3,4,4,5,4,5,5,6,
55 1,2,2,3,2,3,3,4,2,3,3,4,3,4,4,5,
56 2,3,3,4,3,4,4,5,3,4,4,5,4,5,5,6,
57 2,3,3,4,3,4,4,5,3,4,4,5,4,5,5,6,
58 3,4,4,5,4,5,5,6,4,5,5,6,5,6,6,7,
59 1,2,2,3,2,3,3,4,2,3,3,4,3,4,4,5,
60 2,3,3,4,3,4,4,5,3,4,4,5,4,5,5,6,
61 2,3,3,4,3,4,4,5,3,4,4,5,4,5,5,6,
62 3,4,4,5,4,5,5,6,4,5,5,6,5,6,6,7,
63 2,3,3,4,3,4,4,5,3,4,4,5,4,5,5,6,
64 3,4,4,5,4,5,5,6,4,5,5,6,5,6,6,7,
65 3,4,4,5,4,5,5,6,4,5,5,6,5,6,6,7,
66 4,5,5,6,5,6,6,7,5,6,6,7,6,7,7,8
67 };
68
69 static int yaffs_CountBits(__u8 x)
70 {
71         int retVal;
72         retVal = yaffs_countBitsTable[x];
73         return retVal;
74 }
75
76 #endif
77
78
79 #if 0
80 // Stuff using yea olde tags
81 static void yaffs_LoadTagsIntoSpare(yaffs_Spare *sparePtr, yaffs_Tags *tagsPtr);
82 static void yaffs_GetTagsFromSpare(yaffs_Device *dev, yaffs_Spare *sparePtr,yaffs_Tags *tagsPtr);
83
84 static int yaffs_ReadChunkTagsFromNAND(yaffs_Device *dev,int chunkInNAND, yaffs_Tags *tags, int *chunkDeleted);
85 static int yaffs_TagsMatch(const yaffs_Tags *tags, int objectId, int chunkInObject, int chunkDeleted);
86 #else
87 #endif
88
89 // NAND access
90
91
92 static Y_INLINE int yaffs_ReadChunkWithTagsFromNAND(yaffs_Device *dev,int chunkInNAND, __u8 *buffer, yaffs_ExtendedTags *tags);
93 static Y_INLINE int yaffs_WriteChunkWithTagsToNAND(yaffs_Device *dev,int chunkInNAND, const __u8 *data, yaffs_ExtendedTags *tags);
94 static Y_INLINE int yaffs_MarkBlockBad(yaffs_Device *dev, int blockNo);
95 static Y_INLINE int yaffs_QueryInitialBlockState(yaffs_Device *dev,int blockNo, yaffs_BlockState *state,unsigned *sequenceNumber);
96 // Local prototypes
97 static int yaffs_WriteNewChunkWithTagsToNAND(yaffs_Device *dev, const __u8 *buffer, yaffs_ExtendedTags *tags, int useReserve);
98 #if 0
99 static int yaffs_CheckObjectHashSanity(yaffs_Device *dev);
100 #endif
101 static int yaffs_PutChunkIntoFile(yaffs_Object *in,int chunkInInode, int chunkInNAND, int inScan);
102
103 static yaffs_Object *yaffs_CreateNewObject(yaffs_Device *dev,int number,yaffs_ObjectType type);
104 static void yaffs_AddObjectToDirectory(yaffs_Object *directory, yaffs_Object *obj);
105 static int yaffs_UpdateObjectHeader(yaffs_Object *in,const YCHAR *name, int force,int isShrink);
106 static void yaffs_RemoveObjectFromDirectory(yaffs_Object *obj);
107 static int yaffs_CheckStructures(void);
108 static int yaffs_DeleteWorker(yaffs_Object *in, yaffs_Tnode *tn, __u32 level, int chunkOffset,int *limit);
109 static int yaffs_DoGenericObjectDeletion(yaffs_Object *in);
110
111 static yaffs_BlockInfo *yaffs_GetBlockInfo(yaffs_Device *dev,int blockNo);
112
113 static __u8 *yaffs_GetTempBuffer(yaffs_Device *dev,int lineNo);
114 static void yaffs_ReleaseTempBuffer(yaffs_Device *dev, __u8 *buffer, int lineNo);
115
116
117 // Robustification (if it ever comes about...)
118 static void yaffs_RetireBlock(yaffs_Device *dev,int blockInNAND);
119 #if 0
120 static void yaffs_HandleReadDataError(yaffs_Device *dev,int chunkInNAND);
121 #endif
122 static void yaffs_HandleWriteChunkError(yaffs_Device *dev,int chunkInNAND);
123 static void yaffs_HandleWriteChunkOk(yaffs_Device *dev,int chunkInNAND,const __u8 *data, const yaffs_ExtendedTags *tags);
124 static void yaffs_HandleUpdateChunk(yaffs_Device *dev,int chunkInNAND,  const yaffs_ExtendedTags *tags);
125
126 static int  yaffs_CheckChunkErased(struct yaffs_DeviceStruct *dev,int chunkInNAND);
127
128 static int yaffs_UnlinkWorker(yaffs_Object *obj);
129 static void yaffs_DestroyObject(yaffs_Object *obj);
130
131 #if 0
132 static int yaffs_VerifyCompare(const __u8 *d0, const __u8 * d1, const yaffs_Spare *s0, const yaffs_Spare *s1,int dataSize);
133 #endif
134
135 static int yaffs_TagsMatch(const yaffs_ExtendedTags *tags, int objectId, int chunkInObject);
136
137
138 loff_t yaffs_GetFileSize(yaffs_Object *obj);
139
140
141 static int yaffs_AllocateChunk(yaffs_Device *dev,int useReserve);
142
143 static void yaffs_VerifyFreeChunks(yaffs_Device *dev);
144
145 #ifdef YAFFS_PARANOID
146 static int yaffs_CheckFileSanity(yaffs_Object *in);
147 #else
148 #define yaffs_CheckFileSanity(in)
149 #endif
150
151 static void yaffs_InvalidateWholeChunkCache(yaffs_Object *in);
152 static void yaffs_InvalidateChunkCache(yaffs_Object *object, int chunkId);
153
154 static int yaffs_ReadChunkWithTagsFromNAND(yaffs_Device *dev,int chunkInNAND, __u8 *buffer, yaffs_ExtendedTags *tags)
155 {
156         chunkInNAND -= dev->chunkOffset;
157         
158         if(dev->readChunkWithTagsFromNAND)
159                 return dev->readChunkWithTagsFromNAND(dev,chunkInNAND,buffer,tags);
160         else
161                 return yaffs_TagsCompatabilityReadChunkWithTagsFromNAND(dev,chunkInNAND,buffer,tags);
162 }
163
164 static Y_INLINE int yaffs_WriteChunkWithTagsToNAND(yaffs_Device *dev,int chunkInNAND, const __u8 *buffer, yaffs_ExtendedTags *tags)
165 {
166         chunkInNAND -= dev->chunkOffset;
167         
168         if(tags)
169         {
170                 tags->sequenceNumber = dev->sequenceNumber;
171                 tags->chunkUsed = 1;
172                 if(!yaffs_ValidateTags(tags))
173                 {
174                         T(YAFFS_TRACE_ERROR,(TSTR("Writing uninitialised tags" TENDSTR)));
175                         YBUG();
176                 }
177                 T(YAFFS_TRACE_WRITE,(TSTR("Writing chunk %d tags %d %d"TENDSTR),chunkInNAND,tags->objectId,tags->chunkId));
178         }
179         else
180         {
181                         T(YAFFS_TRACE_ERROR,(TSTR("Writing with no tags" TENDSTR)));
182                         YBUG();
183         }
184
185         if(dev->writeChunkWithTagsToNAND)
186                 return dev->writeChunkWithTagsToNAND(dev,chunkInNAND,buffer,tags);
187         else
188                 return yaffs_TagsCompatabilityWriteChunkWithTagsToNAND(dev,chunkInNAND,buffer,tags);
189 }
190
191 static Y_INLINE int yaffs_MarkBlockBad(yaffs_Device *dev, int blockNo)
192 {
193         blockNo -= dev->blockOffset;
194         
195         if(dev->markNANDBlockBad)
196                 return dev->markNANDBlockBad(dev,blockNo);
197         else
198                 return yaffs_TagsCompatabilityMarkNANDBlockBad(dev,blockNo);
199 }
200 static Y_INLINE int yaffs_QueryInitialBlockState(yaffs_Device *dev,int blockNo, yaffs_BlockState *state, unsigned *sequenceNumber)
201 {
202         blockNo -= dev->blockOffset;
203         
204         if(dev->queryNANDBlock)
205                 return dev->queryNANDBlock(dev,blockNo,state,sequenceNumber);
206         else
207                 return yaffs_TagsCompatabilityQueryNANDBlock(dev,blockNo,state,sequenceNumber);
208 }
209
210 int yaffs_EraseBlockInNAND(struct yaffs_DeviceStruct *dev,int blockInNAND)
211 {
212         int result;
213         
214         blockInNAND -= dev->blockOffset;
215
216         dev->nBlockErasures++;
217         result = dev->eraseBlockInNAND(dev,blockInNAND);
218
219         if(!result)result = dev->eraseBlockInNAND(dev,blockInNAND); // If at first we don't succeed, try again *once*.
220         return result;
221 }
222
223 static int yaffs_InitialiseNAND(struct yaffs_DeviceStruct *dev)
224 {
225         return dev->initialiseNAND(dev);
226 }
227
228
229
230
231 // Temporary buffer manipulations
232
233 static __u8 *yaffs_GetTempBuffer(yaffs_Device *dev,int lineNo)
234 {
235         int i,j;
236         for(i = 0; i < YAFFS_N_TEMP_BUFFERS; i++)
237         {
238                 if(dev->tempBuffer[i].line == 0)
239                 {
240                         dev->tempBuffer[i].line = lineNo;
241                         if((i+1) > dev->maxTemp)
242                         {
243                                 dev->maxTemp = i + 1;
244                                 for(j = 0; j <= i; j++)
245                                         dev->tempBuffer[j].maxLine = dev->tempBuffer[j].line;
246                         }       
247                         
248                         return dev->tempBuffer[i].buffer;
249                 }
250         }
251
252         T(YAFFS_TRACE_BUFFERS,(TSTR("Out of temp buffers at line %d, other held by lines:"),lineNo));
253         for(i = 0; i < YAFFS_N_TEMP_BUFFERS; i++)
254         {
255                 T(YAFFS_TRACE_BUFFERS,(TSTR(" %d "),dev->tempBuffer[i].line));
256         }
257         T(YAFFS_TRACE_BUFFERS,(TSTR(" "TENDSTR)));
258         
259         dev->unmanagedTempAllocations++;
260         // Get an unmanaged one
261         return YMALLOC(dev->nBytesPerChunk);    
262         
263         
264 }
265
266 static void yaffs_ReleaseTempBuffer(yaffs_Device *dev, __u8 *buffer, int lineNo)
267 {
268         int i;
269         for(i = 0; i < YAFFS_N_TEMP_BUFFERS; i++)
270         {
271                 if(dev->tempBuffer[i].buffer == buffer)
272                 {
273                         dev->tempBuffer[i].line = 0;
274                         return;
275                 }
276         }
277         
278         if(buffer)
279         {
280                 // assume it is an unmanaged one.
281                 T(YAFFS_TRACE_BUFFERS,(TSTR("Releasing unmanaged temp buffer in line %d" TENDSTR),lineNo));
282                 YFREE(buffer);
283                 dev->unmanagedTempDeallocations++;
284         }
285
286 }
287
288
289 // Chunk bitmap manipulations
290
291 static Y_INLINE __u8 *yaffs_BlockBits(yaffs_Device *dev, int blk)
292 {
293         if(blk < dev->internalStartBlock || blk > dev->internalEndBlock)
294         {
295                 T(YAFFS_TRACE_ERROR,(TSTR("**>> yaffs: BlockBits block %d is not valid" TENDSTR),blk));
296                 YBUG();
297         }
298         return dev->chunkBits + (dev->chunkBitmapStride * (blk - dev->internalStartBlock));
299 }
300
301 static Y_INLINE void yaffs_ClearChunkBits(yaffs_Device *dev,int blk)
302 {
303         __u8 *blkBits = yaffs_BlockBits(dev,blk);
304
305          memset(blkBits,0,dev->chunkBitmapStride);
306 }
307
308 static Y_INLINE void yaffs_ClearChunkBit(yaffs_Device *dev,int blk,int chunk)
309 {
310         __u8 *blkBits = yaffs_BlockBits(dev,blk);
311         
312         blkBits[chunk/8] &=  ~ (1<<(chunk & 7));
313 }
314
315 static Y_INLINE void yaffs_SetChunkBit(yaffs_Device *dev,int blk,int chunk)
316 {
317         __u8 *blkBits = yaffs_BlockBits(dev,blk);
318
319         blkBits[chunk/8] |=   (1<<(chunk & 7));
320 }
321
322 static Y_INLINE int yaffs_CheckChunkBit(yaffs_Device *dev,int blk,int chunk)
323 {
324         __u8 *blkBits = yaffs_BlockBits(dev,blk);
325         return (blkBits[chunk/8] &  (1<<(chunk & 7))) ? 1 :0;
326 }
327
328 static Y_INLINE int yaffs_StillSomeChunkBits(yaffs_Device *dev,int blk)
329 {
330         __u8 *blkBits = yaffs_BlockBits(dev,blk);
331         int i;
332         for(i = 0; i < dev->chunkBitmapStride; i++)
333         {
334                 if(*blkBits) return 1;
335                 blkBits++;
336         }
337         return 0;
338 }
339
340
341 static  Y_INLINE int yaffs_HashFunction(int n)
342 {
343         return (n % YAFFS_NOBJECT_BUCKETS);
344 }
345
346
347 yaffs_Object *yaffs_Root(yaffs_Device *dev)
348 {
349         return dev->rootDir;
350 }
351
352 yaffs_Object *yaffs_LostNFound(yaffs_Device *dev)
353 {
354         return dev->lostNFoundDir;
355 }
356
357
358
359
360 int yaffs_CheckFF(__u8 *buffer,int nBytes)
361 {
362         //Horrible, slow implementation
363         while(nBytes--)
364         {
365                 if(*buffer != 0xFF) return 0;
366                 buffer++;
367         }
368         return 1;
369 }
370
371 static int yaffs_CheckChunkErased(struct yaffs_DeviceStruct *dev,int chunkInNAND)
372 {
373
374         int retval = YAFFS_OK;
375         __u8 *data = yaffs_GetTempBuffer(dev,__LINE__);
376         yaffs_ExtendedTags tags;
377
378 // NCB          dev->readChunkWithTagsFromNAND(dev,chunkInNAND,data,&tags);
379         yaffs_ReadChunkWithTagsFromNAND(dev,chunkInNAND,data,&tags);
380         
381         if(!yaffs_CheckFF(data,dev->nBytesPerChunk) || tags.chunkUsed)
382         {
383                 T(YAFFS_TRACE_NANDACCESS,(TSTR("Chunk %d not erased" TENDSTR),chunkInNAND));
384                 retval = YAFFS_FAIL;
385         }
386
387         yaffs_ReleaseTempBuffer(dev,data,__LINE__);
388         
389         return retval;
390         
391 }
392
393
394
395 #if 1
396 static int yaffs_WriteNewChunkWithTagsToNAND(struct yaffs_DeviceStruct *dev, const __u8 *data, yaffs_ExtendedTags *tags,int useReserve)
397 {
398         int chunk;
399         
400         int writeOk = 1;
401         int attempts = 0;
402         
403
404         
405         do{
406                 chunk = yaffs_AllocateChunk(dev,useReserve);
407         
408                 if(chunk >= 0)
409                 {
410
411                         // First check this chunk is erased...
412 #ifndef CONFIG_YAFFS_DISABLE_CHUNK_ERASED_CHECK
413                         writeOk = yaffs_CheckChunkErased(dev,chunk);
414 #endif          
415                         if(!writeOk)
416                         {
417                                 T(YAFFS_TRACE_ERROR,(TSTR("**>> yaffs chunk %d was not erased" TENDSTR),chunk));
418                         }
419                         else
420                         {
421                                 writeOk =  yaffs_WriteChunkWithTagsToNAND(dev,chunk,data,tags);
422                         }
423                         attempts++;
424
425                         if(writeOk)
426                         {
427                                 // Copy the data into the robustification buffer.
428                                 // NB We do this at the end to prevent duplicates in the case of a write error.
429                                 //Todo
430                                 yaffs_HandleWriteChunkOk(dev,chunk,data,tags);
431                         }
432                         else
433                         {
434                                 yaffs_HandleWriteChunkError(dev,chunk);
435                         }
436                 }
437                 
438         } while(chunk >= 0 && ! writeOk);
439         
440         if(attempts > 1)
441         {
442                 T(YAFFS_TRACE_ERROR,(TSTR("**>> yaffs write required %d attempts" TENDSTR),attempts));
443                 dev->nRetriedWrites+= (attempts - 1);   
444         }
445         
446
447         
448         return chunk;
449 }
450 #endif
451
452
453 ///
454 // Functions for robustisizing
455 //
456 //
457
458 static void yaffs_RetireBlock(yaffs_Device *dev,int blockInNAND)
459 {
460         
461         yaffs_MarkBlockBad(dev,blockInNAND);
462         
463         yaffs_GetBlockInfo(dev,blockInNAND)->blockState = YAFFS_BLOCK_STATE_DEAD;
464
465         dev->nRetiredBlocks++;
466 }
467
468
469 #if 0
470 static int yaffs_RewriteBufferedBlock(yaffs_Device *dev)
471 {
472         dev->doingBufferedBlockRewrite = 1;
473         //
474         //      Remove erased chunks
475         //  Rewrite existing chunks to a new block
476         //      Set current write block to the new block
477         
478         dev->doingBufferedBlockRewrite = 0;
479         
480         return 1;
481 }
482
483
484 static void yaffs_HandleReadDataError(yaffs_Device *dev,int chunkInNAND)
485 {
486         int blockInNAND = chunkInNAND/dev->nChunksPerBlock;
487
488         // Mark the block for retirement
489         yaffs_GetBlockInfo(dev,blockInNAND)->needsRetiring = 1;
490         T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,(TSTR("**>>Block %d marked for retirement" TENDSTR),blockInNAND));
491
492
493         //TODO  
494         // Just do a garbage collection on the affected block then retire the block
495         // NB recursion
496 }
497
498
499 static void yaffs_CheckWrittenBlock(yaffs_Device *dev,int chunkInNAND)
500 {
501 }
502
503 #endif
504
505 static void yaffs_HandleWriteChunkOk(yaffs_Device *dev,int chunkInNAND,const __u8 *data, const yaffs_ExtendedTags *tags)
506 {
507 }
508
509 static void yaffs_HandleUpdateChunk(yaffs_Device *dev,int chunkInNAND, const yaffs_ExtendedTags *tags)
510 {
511 }
512
513 static void yaffs_HandleWriteChunkError(yaffs_Device *dev,int chunkInNAND)
514 {
515         int blockInNAND = chunkInNAND/dev->nChunksPerBlock;
516
517         // Mark the block for retirement
518         yaffs_GetBlockInfo(dev,blockInNAND)->needsRetiring = 1;
519         // Delete the chunk
520         yaffs_DeleteChunk(dev,chunkInNAND,1,__LINE__);
521 }
522
523
524
525 #if 0
526 static int yaffs_VerifyCompare(const __u8 *d0, const __u8 * d1, const yaffs_Spare *s0, const yaffs_Spare *s1,int dataSize)
527 {
528
529
530         if( memcmp(d0,d1,dataSize) != 0 ||
531                 s0->tagByte0 != s1->tagByte0 ||
532                 s0->tagByte1 != s1->tagByte1 ||
533                 s0->tagByte2 != s1->tagByte2 ||
534                 s0->tagByte3 != s1->tagByte3 ||
535                 s0->tagByte4 != s1->tagByte4 ||
536                 s0->tagByte5 != s1->tagByte5 ||
537                 s0->tagByte6 != s1->tagByte6 ||
538                 s0->tagByte7 != s1->tagByte7 ||
539                 s0->ecc1[0]  != s1->ecc1[0]  ||
540                 s0->ecc1[1]  != s1->ecc1[1]  ||
541                 s0->ecc1[2]  != s1->ecc1[2]  ||
542                 s0->ecc2[0]  != s1->ecc2[0]  ||
543                 s0->ecc2[1]  != s1->ecc2[1]  ||
544                 s0->ecc2[2]  != s1->ecc2[2] )
545                 {
546                         return 0;
547                 }
548         
549         return 1;
550 }
551 #endif
552
553
554 ///////////////////////// Object management //////////////////
555 // List of spare objects
556 // The list is hooked together using the first pointer
557 // in the object
558
559 // static yaffs_Object *yaffs_freeObjects = NULL;
560
561 // static int yaffs_nFreeObjects;
562
563 // static yaffs_ObjectList *yaffs_allocatedObjectList = NULL;
564
565 // static yaffs_ObjectBucket yaffs_objectBucket[YAFFS_NOBJECT_BUCKETS];
566
567
568 static __u16 yaffs_CalcNameSum(const YCHAR *name)
569 {
570         __u16 sum = 0;
571         __u16 i = 1;
572         
573         YUCHAR *bname = (YUCHAR *)name;
574         if(bname)
575         {
576                 while ((*bname) && (i <=YAFFS_MAX_NAME_LENGTH))
577                 {
578
579 #ifdef CONFIG_YAFFS_CASE_INSENSITIVE
580                         sum += yaffs_toupper(*bname) * i;
581 #else
582                         sum += (*bname) * i;
583 #endif
584                         i++;
585                         bname++;
586                 }
587         }
588         return sum;
589 }
590
591 void yaffs_SetObjectName(yaffs_Object *obj, const YCHAR *name)
592 {
593 #ifdef CONFIG_YAFFS_SHORT_NAMES_IN_RAM
594                                         if(name && yaffs_strlen(name) <= YAFFS_SHORT_NAME_LENGTH)
595                                         {
596                                                 yaffs_strcpy(obj->shortName,name);
597                                         }
598                                         else
599                                         {
600                                                 obj->shortName[0]=_Y('\0');
601                                         }
602 #endif
603                                         obj->sum = yaffs_CalcNameSum(name);
604 }
605
606 #if 0
607 void yaffs_CalcECC(const __u8 *data, yaffs_Spare *spare)
608 {
609         yaffs_ECCCalculate(data , spare->ecc1);
610         yaffs_ECCCalculate(&data[256] , spare->ecc2);
611 }
612 #endif
613
614
615 ///////////////////////// TNODES ///////////////////////
616
617 // List of spare tnodes
618 // The list is hooked together using the first pointer
619 // in the tnode.
620
621 //static yaffs_Tnode *yaffs_freeTnodes = NULL;
622
623 // static int yaffs_nFreeTnodes;
624
625 //static yaffs_TnodeList *yaffs_allocatedTnodeList = NULL;
626
627
628
629 // yaffs_CreateTnodes creates a bunch more tnodes and
630 // adds them to the tnode free list.
631 // Don't use this function directly
632
633 static int yaffs_CreateTnodes(yaffs_Device *dev,int nTnodes)
634 {
635     int i;
636     yaffs_Tnode *newTnodes;
637     yaffs_TnodeList *tnl;
638     
639     if(nTnodes < 1) return YAFFS_OK;
640    
641         // make these things
642         
643     newTnodes = YMALLOC(nTnodes * sizeof(yaffs_Tnode));
644    
645     if (!newTnodes)
646     {
647                 T(YAFFS_TRACE_ERROR,(TSTR("yaffs: Could not allocate Tnodes"TENDSTR)));
648                 return YAFFS_FAIL;
649     }
650     
651     // Hook them into the free list
652     for(i = 0; i < nTnodes - 1; i++)
653     {
654         newTnodes[i].internal[0] = &newTnodes[i+1];
655 #ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
656         newTnodes[i].internal[YAFFS_NTNODES_INTERNAL] = (void *)1;
657 #endif
658     }
659         
660         newTnodes[nTnodes - 1].internal[0] = dev->freeTnodes;
661 #ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
662         newTnodes[nTnodes - 1].internal[YAFFS_NTNODES_INTERNAL] = (void *)1;
663 #endif
664         dev->freeTnodes = newTnodes;
665         dev->nFreeTnodes+= nTnodes;
666         dev->nTnodesCreated += nTnodes;
667
668         // Now add this bunch of tnodes to a list for freeing up.
669         // NB If we can't add this to the management list it isn't fatal
670         // but it just means we can't free this bunch of tnodes later.
671         tnl = YMALLOC(sizeof(yaffs_TnodeList));
672         if(!tnl)
673         {
674                 T(YAFFS_TRACE_ERROR,(TSTR("yaffs: Could not add tnodes to management list" TENDSTR)));
675                 
676         }
677         else
678         {
679                 tnl->tnodes = newTnodes;
680                 tnl->next = dev->allocatedTnodeList;
681                 dev->allocatedTnodeList = tnl;
682         }
683
684
685         T(YAFFS_TRACE_ALLOCATE,(TSTR("yaffs: Tnodes added" TENDSTR)));
686
687
688         return YAFFS_OK;
689 }
690
691
692 // GetTnode gets us a clean tnode. Tries to make allocate more if we run out
693 static yaffs_Tnode *yaffs_GetTnode(yaffs_Device *dev)
694 {
695         yaffs_Tnode *tn = NULL;
696         
697         // If there are none left make more
698         if(!dev->freeTnodes)
699         {
700                 yaffs_CreateTnodes(dev,YAFFS_ALLOCATION_NTNODES);
701         }
702         
703         if(dev->freeTnodes)
704         {
705                 tn = dev->freeTnodes;
706 #ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
707         if(tn->internal[YAFFS_NTNODES_INTERNAL] != (void *)1)
708                 {
709                         // Hoosterman, this thing looks like it isn't in the list
710                                 T(YAFFS_TRACE_ALWAYS,(TSTR("yaffs: Tnode list bug 1" TENDSTR)));
711                 }
712 #endif
713                 dev->freeTnodes = dev->freeTnodes->internal[0];
714                 dev->nFreeTnodes--;
715                 // zero out
716                 memset(tn,0,sizeof(yaffs_Tnode));
717         }
718         
719
720         return tn;
721 }
722
723
724 // FreeTnode frees up a tnode and puts it back on the free list
725 static void yaffs_FreeTnode(yaffs_Device*dev, yaffs_Tnode *tn)
726 {
727         if(tn)
728         {
729 #ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
730         if(tn->internal[YAFFS_NTNODES_INTERNAL] != 0)
731                 {
732                         // Hoosterman, this thing looks like it is already in the list
733                                 T(YAFFS_TRACE_ALWAYS,(TSTR("yaffs: Tnode list bug 2" TENDSTR)));
734                 }
735                 tn->internal[YAFFS_NTNODES_INTERNAL] = (void *)1;
736 #endif
737                 tn->internal[0] = dev->freeTnodes;
738                 dev->freeTnodes = tn;
739                 dev->nFreeTnodes++;
740         }
741 }
742
743
744 static void yaffs_DeinitialiseTnodes(yaffs_Device*dev)
745 {
746         // Free the list of allocated tnodes
747         yaffs_TnodeList *tmp;
748                 
749         while(dev->allocatedTnodeList)
750         {
751                 tmp =  dev->allocatedTnodeList->next;
752
753                 YFREE(dev->allocatedTnodeList->tnodes);
754                 YFREE(dev->allocatedTnodeList);
755                 dev->allocatedTnodeList = tmp;
756                 
757         }
758         
759         dev->freeTnodes = NULL;
760         dev->nFreeTnodes = 0;
761 }
762
763 static void yaffs_InitialiseTnodes(yaffs_Device*dev)
764 {
765         dev->allocatedTnodeList = NULL;
766         dev->freeTnodes = NULL;
767         dev->nFreeTnodes = 0;
768         dev->nTnodesCreated = 0;
769
770 }
771
772 #if 0
773 void yaffs_TnodeTest(yaffs_Device *dev)
774 {
775
776         int i;
777         int j;
778         yaffs_Tnode *tn[1000];
779         
780         YINFO("Testing TNodes");
781         
782         for(j = 0; j < 50; j++)
783         {
784                 for(i = 0; i < 1000; i++)
785                 {
786                         tn[i] = yaffs_GetTnode(dev);
787                         if(!tn[i])
788                         {
789                                 YALERT("Getting tnode failed");
790                         }
791                 }
792                 for(i = 0; i < 1000; i+=3)
793                 {
794                         yaffs_FreeTnode(dev,tn[i]);
795                         tn[i] = NULL;
796                 }
797                 
798         }
799 }
800 #endif
801
802
803 ////////////////// END OF TNODE MANIPULATION ///////////////////////////
804
805 /////////////// Functions to manipulate the look-up tree (made up of tnodes)
806 // The look up tree is represented by the top tnode and the number of topLevel
807 // in the tree. 0 means only the level 0 tnode is in the tree.
808
809
810 // FindLevel0Tnode finds the level 0 tnode, if one exists.
811 // Used when reading.....
812 static yaffs_Tnode *yaffs_FindLevel0Tnode(yaffs_Device *dev,yaffs_FileStructure *fStruct, __u32 chunkId)
813 {
814         
815         yaffs_Tnode *tn = fStruct->top;
816         __u32 i;
817         int requiredTallness;   
818         int level = fStruct->topLevel;
819         
820         // Check sane level and chunk Id
821         if(level < 0 || level > YAFFS_TNODES_MAX_LEVEL)
822         {
823 //              char str[50];
824 //              sprintf(str,"Bad level %d",level);
825 //              YALERT(str);
826                 return NULL;
827         }
828         
829         if(chunkId > YAFFS_MAX_CHUNK_ID)
830         {
831 //              char str[50];
832 //              sprintf(str,"Bad chunkId %d",chunkId);
833 //              YALERT(str);
834                 return NULL;
835         }
836
837         // First check we're tall enough (ie enough topLevel)
838         
839         i = chunkId >> (/*dev->chunkGroupBits  + */YAFFS_TNODES_LEVEL0_BITS);
840         requiredTallness = 0;
841         while(i)
842         {
843                 i >>= YAFFS_TNODES_INTERNAL_BITS;
844                 requiredTallness++;
845         }
846         
847         
848         if(requiredTallness > fStruct->topLevel)
849         {
850                 // Not tall enough, so we can't find it, return NULL.
851                 return NULL;
852         }
853                 
854         
855         // Traverse down to level 0
856         while (level > 0 && tn)
857         {
858             tn = tn->internal[(chunkId >>(/* dev->chunkGroupBits + */ YAFFS_TNODES_LEVEL0_BITS + (level-1) * YAFFS_TNODES_INTERNAL_BITS)) & 
859                                YAFFS_TNODES_INTERNAL_MASK]; 
860                 level--;
861         
862         }
863         
864         return tn;              
865 }
866
867 // AddOrFindLevel0Tnode finds the level 0 tnode if it exists, otherwise first expands the tree.
868 // This happens in two steps:
869 //  1. If the tree isn't tall enough, then make it taller.
870 //  2. Scan down the tree towards the level 0 tnode adding tnodes if required.
871 //
872 // Used when modifying the tree.
873 //
874 static yaffs_Tnode *yaffs_AddOrFindLevel0Tnode(yaffs_Device *dev, yaffs_FileStructure *fStruct, __u32 chunkId)
875 {
876         
877         yaffs_Tnode *tn; 
878         
879         int requiredTallness;
880         int i;
881         int l;
882         
883         __u32 x;
884                 
885         
886         //T((TSTR("AddOrFind topLevel=%d, chunk=%d"),fStruct->topLevel,chunkId));
887         
888         // Check sane level and page Id
889         if(fStruct->topLevel < 0 || fStruct->topLevel > YAFFS_TNODES_MAX_LEVEL)
890         {
891 //              char str[50];
892 //              sprintf(str,"Bad level %d",fStruct->topLevel);
893 //              YALERT(str);
894                 return NULL;
895         }
896         
897         if(chunkId > YAFFS_MAX_CHUNK_ID)
898         {
899 //              char str[50];
900 //              sprintf(str,"Bad chunkId %d",chunkId);
901 //              YALERT(str);
902                 return NULL;
903         }
904         
905         // First check we're tall enough (ie enough topLevel)
906         
907         x = chunkId >> (/*dev->chunkGroupBits + */YAFFS_TNODES_LEVEL0_BITS);
908         requiredTallness = 0;
909         while(x)
910         {
911                 x >>= YAFFS_TNODES_INTERNAL_BITS;
912                 requiredTallness++;
913         }
914         
915         //T((TSTR(" required=%d"),requiredTallness));
916         
917         
918         if(requiredTallness > fStruct->topLevel)
919         {
920                 // Not tall enough,gotta make the tree taller
921                 for(i = fStruct->topLevel; i < requiredTallness; i++)
922                 {
923                         //T((TSTR(" add new top")));
924                         
925                         tn = yaffs_GetTnode(dev);
926                         
927                         if(tn)
928                         {
929                                 tn->internal[0] = fStruct->top;
930                                 fStruct->top = tn;
931                         }
932                         else
933                         {
934                                         T(YAFFS_TRACE_ERROR,(TSTR("yaffs: no more tnodes" TENDSTR)));
935                         }
936                 }
937                 
938                 fStruct->topLevel = requiredTallness;
939         }
940         
941         
942         // Traverse down to level 0, adding anything we need
943         
944         l = fStruct->topLevel;
945         tn = fStruct->top;
946         while (l > 0 && tn)
947         {
948                 x = (chunkId >> (/*dev->chunkGroupBits + */YAFFS_TNODES_LEVEL0_BITS + (l-1) * YAFFS_TNODES_INTERNAL_BITS)) & 
949                                YAFFS_TNODES_INTERNAL_MASK;
950                                
951                 //T((TSTR(" [%d:%d]"),l,i));
952                 
953             if(!tn->internal[x])
954             {
955                 //T((TSTR(" added")));
956                 
957                 tn->internal[x] = yaffs_GetTnode(dev);
958             }
959             
960             tn =        tn->internal[x];
961                 l--;
962         
963         }
964         
965         //TSTR(TENDSTR)));
966         
967         return tn;              
968 }
969
970
971 int yaffs_FindChunkInGroup(yaffs_Device *dev, int theChunk, yaffs_ExtendedTags *tags, int objectId, int chunkInInode)
972 {
973         int j;
974         
975                                         
976         for(j = 0; theChunk && j < dev->chunkGroupSize; j++)
977         {
978                 if(yaffs_CheckChunkBit(dev,theChunk / dev->nChunksPerBlock,theChunk % dev->nChunksPerBlock))
979                 {
980                         yaffs_ReadChunkWithTagsFromNAND(dev,theChunk,NULL,tags);
981                         if(yaffs_TagsMatch(tags,objectId,chunkInInode))
982                         {
983                                 // found it;
984                                 return theChunk;
985                                         
986                         }
987                 }
988                 theChunk++;
989         }
990         return -1;
991 }
992
993 // DeleteWorker scans backwards through the tnode tree and deletes all the
994 // chunks and tnodes in the file
995 // Returns 1 if the tree was deleted. Returns 0 if it stopped early due to hitting the limit and the delete is incomplete.
996
997 static int yaffs_DeleteWorker(yaffs_Object *in, yaffs_Tnode *tn, __u32 level, int chunkOffset,int *limit)
998 {
999         int i;
1000         int chunkInInode;
1001         int theChunk;
1002         yaffs_ExtendedTags tags;
1003         int foundChunk;
1004         yaffs_Device *dev = in->myDev;
1005
1006         int allDone = 1;
1007         
1008         
1009         if(tn)
1010         {
1011                 if(level > 0)
1012                 {
1013                 
1014                         for(i = YAFFS_NTNODES_INTERNAL -1; allDone && i >= 0; i--)
1015                         {
1016                             if(tn->internal[i])
1017                         {
1018                                         if(limit && (*limit) < 0)
1019                                         {
1020                                                 allDone = 0;
1021                                         }
1022                                         else
1023                                         {
1024                                                 allDone = yaffs_DeleteWorker(in,tn->internal[i],level - 1,
1025                                                                                 (chunkOffset << YAFFS_TNODES_INTERNAL_BITS ) + i ,limit);
1026                                         }
1027                                         if(allDone)
1028                                         {
1029                                                 yaffs_FreeTnode(dev,tn->internal[i]);
1030                                         tn->internal[i] = NULL;
1031                                         }
1032                             }
1033                     
1034                         }
1035                         return (allDone) ? 1 : 0;
1036                 }
1037                 else if(level == 0)
1038                 {
1039                         int hitLimit = 0;
1040                         
1041                         for(i = YAFFS_NTNODES_LEVEL0 -1; i >= 0 && !hitLimit; i--)
1042                         {
1043                             if(tn->level0[i])
1044                         {
1045                                         
1046                                         chunkInInode = (chunkOffset << YAFFS_TNODES_LEVEL0_BITS ) + i;
1047                                         
1048                                         theChunk =  tn->level0[i] << dev->chunkGroupBits;
1049                                         
1050                                         foundChunk = yaffs_FindChunkInGroup(dev,theChunk,&tags,in->objectId,chunkInInode);
1051                                         
1052                                         if(foundChunk > 0)
1053                                         {
1054                                                 yaffs_DeleteChunk(dev,foundChunk,1,__LINE__);
1055                                                 in->nDataChunks--;
1056                                                 if(limit)
1057                                                 { 
1058                                                         *limit = *limit-1;
1059                                                         if(*limit <= 0) 
1060                                                         { 
1061                                                                 hitLimit = 1;
1062                                                         }
1063                                                 }
1064                                         
1065                                         }
1066                                         
1067                                 tn->level0[i] = 0;
1068                             }
1069                     
1070                         }
1071                         return (i < 0) ? 1 : 0;
1072
1073                         
1074                 }
1075                 
1076         }
1077         
1078         return 1;
1079         
1080 }
1081
1082
1083 static void yaffs_SoftDeleteChunk(yaffs_Device *dev, int chunk)
1084 {
1085
1086         yaffs_BlockInfo *theBlock;                                      
1087         
1088         T(YAFFS_TRACE_DELETION,(TSTR("soft delete chunk %d" TENDSTR),chunk));
1089                                                 
1090         theBlock =      yaffs_GetBlockInfo(dev,  chunk/dev->nChunksPerBlock);
1091         if(theBlock)
1092         {
1093                 theBlock->softDeletions++;
1094                 dev->nFreeChunks++;
1095         }
1096 }
1097
1098 // SoftDeleteWorker scans backwards through the tnode tree and soft deletes all the chunks in the file.
1099 // All soft deleting does is increment the block's softdelete count and pulls the chunk out
1100 // of the tnode.
1101 // THus, essentially this is the same as DeleteWorker except that the chunks are soft deleted.
1102 //
1103 static int yaffs_SoftDeleteWorker(yaffs_Object *in, yaffs_Tnode *tn, __u32 level, int chunkOffset)
1104 {
1105         int i;
1106         int theChunk;
1107         int allDone = 1;
1108         yaffs_Device *dev = in->myDev;
1109         
1110         
1111         if(tn)
1112         {
1113                 if(level > 0)
1114                 {
1115                 
1116                         for(i = YAFFS_NTNODES_INTERNAL -1; allDone && i >= 0; i--)
1117                         {
1118                             if(tn->internal[i])
1119                         {
1120                                                 allDone = yaffs_SoftDeleteWorker(in,tn->internal[i],level - 1,
1121                                                                                 (chunkOffset << YAFFS_TNODES_INTERNAL_BITS ) + i);
1122                                         if(allDone)
1123                                         {
1124                                                 yaffs_FreeTnode(dev,tn->internal[i]);
1125                                         tn->internal[i] = NULL;
1126                                         }
1127                                         else
1128                                         {
1129                                                 //Hoosterman... how could this happen.
1130                                         }                           
1131                                 }                   
1132                         }
1133                         return (allDone) ? 1 : 0;
1134                 }
1135                 else if(level == 0)
1136                 {
1137                         
1138                         for(i = YAFFS_NTNODES_LEVEL0 -1; i >=0; i--)
1139                         {
1140                             if(tn->level0[i])
1141                         {
1142                                         // Note this does not find the real chunk, only the chunk group.
1143                                         // We make an assumption that a chunk group is niot larger than a block.
1144                                         theChunk =  (tn->level0[i] << dev->chunkGroupBits);
1145                                         
1146                                         yaffs_SoftDeleteChunk(dev,theChunk);
1147                                 tn->level0[i] = 0;
1148                             }
1149                     
1150                         }
1151                         return 1;
1152                         
1153                 }
1154                 
1155         }
1156         
1157         return 1;
1158                 
1159 }
1160
1161
1162
1163 static void yaffs_SoftDeleteFile(yaffs_Object *obj)
1164 {
1165         if(obj->deleted &&
1166            obj->variantType == YAFFS_OBJECT_TYPE_FILE &&
1167            !obj->softDeleted)
1168         {
1169                 if(obj->nDataChunks <= 0)
1170                 {
1171                                 // Empty file with no duplicate object headers, just delete it immediately
1172                                 yaffs_FreeTnode(obj->myDev,obj->variant.fileVariant.top);
1173                                 obj->variant.fileVariant.top = NULL;
1174                                 T(YAFFS_TRACE_TRACING,(TSTR("yaffs: Deleting empty file %d" TENDSTR),obj->objectId));
1175                                 yaffs_DoGenericObjectDeletion(obj);     
1176                 }
1177                 else
1178                 {
1179                         yaffs_SoftDeleteWorker(obj, obj->variant.fileVariant.top, obj->variant.fileVariant.topLevel, 0);
1180                         obj->softDeleted = 1;
1181                 }
1182         }
1183 }
1184
1185
1186
1187
1188
1189 // Pruning removes any part of the file structure tree that is beyond the
1190 // bounds of the file (ie that does not point to chunks).
1191 //
1192 // A file should only get pruned when its size is reduced.
1193 //
1194 // Before pruning, the chunks must be pulled from the tree and the
1195 // level 0 tnode entries must be zeroed out.
1196 // Could also use this for file deletion, but that's probably better handled
1197 // by a special case.
1198
1199 // yaffs_PruneWorker should only be called by yaffs_PruneFileStructure()
1200
1201 static yaffs_Tnode *yaffs_PruneWorker(yaffs_Device *dev, yaffs_Tnode *tn, __u32 level, int del0)
1202 {
1203         int i;
1204         int hasData;
1205         
1206         if(tn)
1207         {
1208                 hasData = 0;
1209                 
1210                 for(i = 0; i < YAFFS_NTNODES_INTERNAL; i++)
1211                 {
1212                     if(tn->internal[i] && level > 0)
1213                     {
1214                         tn->internal[i] = yaffs_PruneWorker(dev,tn->internal[i],level - 1, ( i == 0) ? del0 : 1);
1215                     }
1216                     
1217                     if(tn->internal[i])
1218                     {
1219                         hasData++;
1220                         }
1221                 }
1222                 
1223                 if(hasData == 0 && del0)
1224                 {
1225                         // Free and return NULL
1226                         
1227                         yaffs_FreeTnode(dev,tn);
1228                         tn = NULL;
1229                 }
1230                 
1231         }
1232
1233         return tn;
1234         
1235 }
1236
1237 static int yaffs_PruneFileStructure(yaffs_Device *dev, yaffs_FileStructure *fStruct)
1238 {
1239         int i;
1240         int hasData;
1241         int done = 0;
1242         yaffs_Tnode *tn;
1243         
1244         if(fStruct->topLevel > 0)
1245         {
1246                 fStruct->top = yaffs_PruneWorker(dev,fStruct->top, fStruct->topLevel,0);
1247                 
1248                 // Now we have a tree with all the non-zero branches NULL but the height
1249                 // is the same as it was.
1250                 // Let's see if we can trim internal tnodes to shorten the tree.
1251                 // We can do this if only the 0th element in the tnode is in use 
1252                 // (ie all the non-zero are NULL)
1253                 
1254                 while(fStruct->topLevel && !done)
1255                 {
1256                         tn = fStruct->top;
1257                         
1258                         hasData = 0;
1259                         for(i = 1; i <YAFFS_NTNODES_INTERNAL; i++)
1260                         {
1261                                 if(tn->internal[i])
1262                         {
1263                                 hasData++;
1264                                 }
1265                         }
1266                         
1267                         if(!hasData)
1268                         {
1269                                 fStruct->top = tn->internal[0];
1270                                 fStruct->topLevel--;
1271                                 yaffs_FreeTnode(dev,tn);
1272                         }
1273                         else
1274                         {
1275                                 done = 1;
1276                         }
1277                 }
1278         }
1279         
1280         return YAFFS_OK;
1281 }
1282
1283
1284
1285
1286
1287 /////////////////////// End of File Structure functions. /////////////////
1288
1289 // yaffs_CreateFreeObjects creates a bunch more objects and
1290 // adds them to the object free list.
1291 static int yaffs_CreateFreeObjects(yaffs_Device *dev, int nObjects)
1292 {
1293     int i;
1294     yaffs_Object *newObjects;
1295     yaffs_ObjectList *list;
1296     
1297     if(nObjects < 1) return YAFFS_OK;
1298    
1299         // make these things
1300         
1301     newObjects = YMALLOC(nObjects * sizeof(yaffs_Object));
1302    
1303     if (!newObjects)
1304     {
1305                 T(YAFFS_TRACE_ALLOCATE,(TSTR("yaffs: Could not allocate more objects" TENDSTR)));
1306                 return YAFFS_FAIL;
1307     }
1308     
1309     // Hook them into the free list
1310     for(i = 0; i < nObjects - 1; i++)
1311     {
1312         newObjects[i].siblings.next = (struct list_head *)(&newObjects[i+1]);
1313     }
1314         
1315         newObjects[nObjects - 1].siblings.next = (void *)dev->freeObjects;
1316         dev->freeObjects = newObjects;
1317         dev->nFreeObjects+= nObjects;
1318         dev->nObjectsCreated+= nObjects;
1319         
1320         // Now add this bunch of Objects to a list for freeing up.
1321         
1322         list = YMALLOC(sizeof(yaffs_ObjectList));
1323         if(!list)
1324         {
1325                 T(YAFFS_TRACE_ALLOCATE,(TSTR("Could not add objects to management list" TENDSTR)));
1326         }
1327         else
1328         {
1329                 list->objects = newObjects;
1330                 list->next = dev->allocatedObjectList;
1331                 dev->allocatedObjectList = list;
1332         }
1333         
1334         
1335         
1336         return YAFFS_OK;
1337 }
1338
1339
1340 // AllocateEmptyObject gets us a clean Object. Tries to make allocate more if we run out
1341 static yaffs_Object *yaffs_AllocateEmptyObject(yaffs_Device *dev)
1342 {
1343         yaffs_Object *tn = NULL;
1344         
1345         // If there are none left make more
1346         if(!dev->freeObjects)
1347         {
1348                 yaffs_CreateFreeObjects(dev,YAFFS_ALLOCATION_NOBJECTS);
1349         }
1350         
1351         if(dev->freeObjects)
1352         {
1353                 tn = dev->freeObjects;
1354                 dev->freeObjects = (yaffs_Object *)(dev->freeObjects->siblings.next);
1355                 dev->nFreeObjects--;
1356                 
1357                 // Now sweeten it up...
1358         
1359                 memset(tn,0,sizeof(yaffs_Object));
1360                 tn->myDev = dev;
1361                 tn->chunkId = -1;
1362                 tn->variantType = YAFFS_OBJECT_TYPE_UNKNOWN;
1363                 INIT_LIST_HEAD(&(tn->hardLinks));
1364                 INIT_LIST_HEAD(&(tn->hashLink));
1365                 INIT_LIST_HEAD(&tn->siblings);
1366                 
1367                 // Add it to the lost and found directory.
1368                 // NB Can't put root or lostNFound in lostNFound so
1369                 // check if lostNFound exists first
1370                 if(dev->lostNFoundDir)
1371                 {
1372                         yaffs_AddObjectToDirectory(dev->lostNFoundDir,tn);      
1373                 }
1374         }
1375         
1376
1377         return tn;
1378 }
1379
1380 static yaffs_Object *yaffs_CreateFakeDirectory(yaffs_Device *dev,int number,__u32 mode)
1381 {
1382
1383         yaffs_Object *obj = yaffs_CreateNewObject(dev,number,YAFFS_OBJECT_TYPE_DIRECTORY);              
1384         if(obj)
1385         {
1386                 obj->fake = 1;                  // it is fake so it has no NAND presence...
1387                 obj->renameAllowed= 0;  // ... and we're not allowed to rename it...
1388                 obj->unlinkAllowed= 0;  // ... or unlink it
1389                 obj->deleted = 0;
1390                 obj->unlinked = 0;
1391                 obj->yst_mode = mode;
1392                 obj->myDev = dev;
1393                 obj->chunkId = 0; // Not a valid chunk.
1394         }
1395         
1396         return obj;
1397         
1398 }
1399
1400
1401 static void yaffs_UnhashObject(yaffs_Object *tn)
1402 {
1403         int bucket;
1404         yaffs_Device *dev = tn->myDev;
1405         
1406         
1407         // If it is still linked into the bucket list, free from the list
1408         if(!list_empty(&tn->hashLink))
1409         {
1410                 list_del_init(&tn->hashLink);
1411                 bucket =  yaffs_HashFunction(tn->objectId);
1412                 dev->objectBucket[bucket].count--;
1413         }
1414         
1415 }
1416
1417
1418 // FreeObject frees up a Object and puts it back on the free list
1419 static void yaffs_FreeObject(yaffs_Object *tn)
1420 {
1421
1422         yaffs_Device *dev = tn->myDev;
1423         
1424 #ifdef  __KERNEL__
1425         if(tn->myInode)
1426         {
1427                 // We're still hooked up to a cached inode.
1428                 // Don't delete now, but mark for later deletion
1429                 tn->deferedFree = 1;
1430                 return;
1431         }
1432 #endif
1433         
1434         yaffs_UnhashObject(tn);
1435         
1436         // Link into the free list.
1437         tn->siblings.next = (struct list_head *)(dev->freeObjects);
1438         dev->freeObjects = tn;
1439         dev->nFreeObjects++;
1440 }
1441
1442
1443
1444 #ifdef __KERNEL__
1445
1446 void yaffs_HandleDeferedFree(yaffs_Object *obj)
1447 {
1448         if(obj->deferedFree)
1449         {
1450            yaffs_FreeObject(obj);
1451         }
1452 }
1453
1454 #endif
1455
1456
1457
1458 static void yaffs_DeinitialiseObjects(yaffs_Device *dev)
1459 {
1460         // Free the list of allocated Objects
1461         
1462         yaffs_ObjectList *tmp;
1463         
1464         while( dev->allocatedObjectList)
1465         {
1466                 tmp =  dev->allocatedObjectList->next;
1467                 YFREE(dev->allocatedObjectList->objects);
1468                 YFREE(dev->allocatedObjectList);
1469                 
1470                 dev->allocatedObjectList =  tmp;
1471         }
1472         
1473         dev->freeObjects = NULL;
1474         dev->nFreeObjects = 0;
1475 }
1476
1477 static void yaffs_InitialiseObjects(yaffs_Device *dev)
1478 {
1479         int i;
1480         
1481         dev->allocatedObjectList = NULL;
1482         dev->freeObjects = NULL;
1483         dev->nFreeObjects = 0;
1484         
1485         for(i = 0; i < YAFFS_NOBJECT_BUCKETS; i++)
1486         {
1487                 INIT_LIST_HEAD(&dev->objectBucket[i].list);
1488                 dev->objectBucket[i].count = 0; 
1489         }
1490
1491 }
1492
1493
1494
1495
1496
1497
1498 int yaffs_FindNiceObjectBucket(yaffs_Device *dev)
1499 {
1500         static int x = 0;
1501         int i;
1502         int l = 999;
1503         int lowest = 999999;
1504
1505                 
1506         // First let's see if we can find one that's empty.
1507         
1508         for(i = 0; i < 10 && lowest > 0; i++)
1509          {
1510                 x++;
1511                 x %=  YAFFS_NOBJECT_BUCKETS;
1512                 if(dev->objectBucket[x].count < lowest)
1513                 {
1514                         lowest = dev->objectBucket[x].count;
1515                         l = x;
1516                 }
1517                 
1518         }
1519         
1520         // If we didn't find an empty list, then try
1521         // looking a bit further for a short one
1522         
1523         for(i = 0; i < 10 && lowest > 3; i++)
1524          {
1525                 x++;
1526                 x %=  YAFFS_NOBJECT_BUCKETS;
1527                 if(dev->objectBucket[x].count < lowest)
1528                 {
1529                         lowest = dev->objectBucket[x].count;
1530                         l = x;
1531                 }
1532                 
1533         }
1534         
1535         return l;
1536 }
1537
1538 static int yaffs_CreateNewObjectNumber(yaffs_Device *dev)
1539 {
1540         int bucket = yaffs_FindNiceObjectBucket(dev);
1541         
1542         // Now find an object value that has not already been taken
1543         // by scanning the list.
1544         
1545         int found = 0;
1546         struct list_head *i;
1547         
1548         __u32 n = (__u32)bucket;
1549
1550         //yaffs_CheckObjectHashSanity();        
1551         
1552         while(!found)
1553         {
1554                 found = 1;
1555                 n +=  YAFFS_NOBJECT_BUCKETS;
1556                 if(1 ||dev->objectBucket[bucket].count > 0)
1557                 {
1558                         list_for_each(i,&dev->objectBucket[bucket].list)
1559                         {
1560                                 // If there is already one in the list
1561                                 if(i && list_entry(i, yaffs_Object,hashLink)->objectId == n)
1562                                 {
1563                                         found = 0;
1564                                 }
1565                         }
1566                 }
1567         }
1568         
1569         //T(("bucket %d count %d inode %d\n",bucket,yaffs_objectBucket[bucket].count,n);
1570         
1571         return n;       
1572 }
1573
1574 void yaffs_HashObject(yaffs_Object *in)
1575 {
1576         int bucket = yaffs_HashFunction(in->objectId);
1577         yaffs_Device *dev = in->myDev;
1578         
1579         if(!list_empty(&in->hashLink))
1580         {
1581                 //YINFO("!!!");
1582         }
1583
1584         
1585         list_add(&in->hashLink,&dev->objectBucket[bucket].list);
1586         dev->objectBucket[bucket].count++;
1587
1588 }
1589
1590 yaffs_Object *yaffs_FindObjectByNumber(yaffs_Device *dev,__u32 number)
1591 {
1592         int bucket = yaffs_HashFunction(number);
1593         struct list_head *i;
1594         yaffs_Object *in;
1595         
1596         list_for_each(i,&dev->objectBucket[bucket].list)
1597         {
1598                 // Look if it is in the list
1599                 if(i)
1600                 {
1601                         in = list_entry(i, yaffs_Object,hashLink);
1602                         if(in->objectId == number)
1603                         {
1604 #ifdef __KERNEL__
1605                                 // Don't tell the VFS about this one if it is defered free
1606                                 if(in->deferedFree)
1607                                   return NULL;
1608 #endif
1609                                   
1610                                 return in;
1611                         }
1612                 }
1613         }
1614         
1615         return NULL;
1616 }
1617
1618
1619
1620 yaffs_Object *yaffs_CreateNewObject(yaffs_Device *dev,int number,yaffs_ObjectType type)
1621 {
1622                 
1623         yaffs_Object *theObject;
1624
1625         if(number < 0)
1626         {
1627                 number = yaffs_CreateNewObjectNumber(dev);
1628         }
1629         
1630         theObject = yaffs_AllocateEmptyObject(dev);
1631         
1632         if(theObject)
1633         {
1634                 theObject->fake = 0;
1635                 theObject->renameAllowed = 1;
1636                 theObject->unlinkAllowed = 1;
1637                 theObject->objectId = number;
1638                 yaffs_HashObject(theObject);
1639                 theObject->variantType = type;
1640 #ifdef CONFIG_YAFFS_WINCE
1641                 yfsd_WinFileTimeNow(theObject->win_atime);
1642                 theObject->win_ctime[0] = theObject->win_mtime[0] = theObject->win_atime[0];
1643                 theObject->win_ctime[1] = theObject->win_mtime[1] = theObject->win_atime[1];
1644
1645 #else
1646
1647                 theObject->yst_atime = theObject->yst_mtime = theObject->yst_ctime = Y_CURRENT_TIME;            
1648 #endif
1649                 switch(type)
1650                 {
1651                         case YAFFS_OBJECT_TYPE_FILE: 
1652                                 theObject->variant.fileVariant.fileSize = 0;
1653                                 theObject->variant.fileVariant.scannedFileSize = 0;
1654                                 theObject->variant.fileVariant.shrinkSize = 0xFFFFFFFF; // max __u32
1655                                 theObject->variant.fileVariant.topLevel = 0;
1656                                 theObject->variant.fileVariant.top  = yaffs_GetTnode(dev);
1657                                 break;
1658                         case YAFFS_OBJECT_TYPE_DIRECTORY:
1659                                 INIT_LIST_HEAD(&theObject->variant.directoryVariant.children);
1660                                 break;
1661                         case YAFFS_OBJECT_TYPE_SYMLINK:
1662                                 // No action required
1663                                 break;
1664                         case YAFFS_OBJECT_TYPE_HARDLINK:
1665                                 // No action required
1666                                 break;
1667                         case YAFFS_OBJECT_TYPE_SPECIAL:
1668                                 // No action required
1669                                 break;
1670                         case YAFFS_OBJECT_TYPE_UNKNOWN:
1671                                 // todo this should not happen
1672                                 break;
1673                 }
1674         }
1675         
1676         return theObject;
1677 }
1678
1679 yaffs_Object *yaffs_FindOrCreateObjectByNumber(yaffs_Device *dev, int number,yaffs_ObjectType type)
1680 {
1681         yaffs_Object *theObject = NULL;
1682         
1683         if(number > 0)
1684         {
1685                 theObject = yaffs_FindObjectByNumber(dev,number);
1686         }
1687         
1688         if(!theObject)
1689         {
1690                 theObject = yaffs_CreateNewObject(dev,number,type);
1691         }
1692         
1693         return theObject;
1694
1695 }
1696
1697 YCHAR *yaffs_CloneString(const YCHAR *str)
1698 {
1699         YCHAR *newStr = NULL;
1700         
1701         if(str && *str)
1702         {
1703                 newStr = YMALLOC((yaffs_strlen(str) + 1) * sizeof(YCHAR));
1704                 yaffs_strcpy(newStr,str);
1705         }
1706
1707         return newStr;
1708         
1709 }
1710
1711 //
1712 // Mknod (create) a new object.
1713 // equivalentObject only has meaning for a hard link;
1714 // aliasString only has meaning for a sumlink.
1715 // rdev only has meaning for devices (a subset of special objects)
1716 yaffs_Object *yaffs_MknodObject( yaffs_ObjectType type,
1717                                                                  yaffs_Object *parent,
1718                                                                  const YCHAR *name, 
1719                                                                  __u32 mode,
1720                                                                  __u32 uid,
1721                                                                  __u32 gid,
1722                                                                  yaffs_Object *equivalentObject,
1723                                                                  const YCHAR *aliasString,
1724                                                                  __u32 rdev)
1725 {
1726         yaffs_Object *in;
1727
1728         yaffs_Device *dev = parent->myDev;
1729         
1730         // Check if the entry exists. If it does then fail the call since we don't want a dup.
1731         if(yaffs_FindObjectByName(parent,name))
1732         {
1733                 return NULL;
1734         }
1735         
1736         in = yaffs_CreateNewObject(dev,-1,type);
1737         
1738         if(in)
1739         {
1740                 in->chunkId = -1;
1741                 in->valid = 1;
1742                 in->variantType = type;
1743
1744                 in->yst_mode  = mode;
1745                 
1746 #ifdef CONFIG_YAFFS_WINCE
1747                 yfsd_WinFileTimeNow(in->win_atime);
1748                 in->win_ctime[0] = in->win_mtime[0] = in->win_atime[0];
1749                 in->win_ctime[1] = in->win_mtime[1] = in->win_atime[1];
1750                 
1751 #else
1752                 in->yst_atime = in->yst_mtime = in->yst_ctime = Y_CURRENT_TIME;
1753
1754                 in->yst_rdev  = rdev;
1755                 in->yst_uid   = uid;
1756                 in->yst_gid   = gid;
1757 #endif          
1758                 in->nDataChunks = 0;
1759
1760                 yaffs_SetObjectName(in,name);
1761                 in->dirty = 1;
1762                 
1763                 yaffs_AddObjectToDirectory(parent,in);
1764                 
1765                 in->myDev = parent->myDev;
1766                 
1767                                 
1768                 switch(type)
1769                 {
1770                         case YAFFS_OBJECT_TYPE_SYMLINK:
1771                                 in->variant.symLinkVariant.alias = yaffs_CloneString(aliasString);
1772                                 break;
1773                         case YAFFS_OBJECT_TYPE_HARDLINK:
1774                                 in->variant.hardLinkVariant.equivalentObject = equivalentObject;
1775                                 in->variant.hardLinkVariant.equivalentObjectId = equivalentObject->objectId;
1776                                 list_add(&in->hardLinks,&equivalentObject->hardLinks);
1777                                 break;
1778                         case YAFFS_OBJECT_TYPE_FILE: // do nothing
1779                         case YAFFS_OBJECT_TYPE_DIRECTORY: // do nothing
1780                         case YAFFS_OBJECT_TYPE_SPECIAL: // do nothing
1781                         case YAFFS_OBJECT_TYPE_UNKNOWN:
1782                                 break;
1783                 }
1784
1785                 if(/*yaffs_GetNumberOfFreeChunks(dev) <= 0 || */
1786                    yaffs_UpdateObjectHeader(in,name,0,0) < 0)
1787                 {
1788                         // Could not create the object header, fail the creation
1789                         yaffs_DestroyObject(in);
1790                         in = NULL;
1791                 }
1792
1793         }
1794         
1795         return in;
1796 }
1797
1798 yaffs_Object *yaffs_MknodFile(yaffs_Object *parent,const YCHAR *name, __u32 mode, __u32 uid, __u32 gid)
1799 {
1800         return yaffs_MknodObject(YAFFS_OBJECT_TYPE_FILE,parent,name,mode,uid,gid,NULL,NULL,0);
1801 }
1802
1803 yaffs_Object *yaffs_MknodDirectory(yaffs_Object *parent,const YCHAR *name, __u32 mode, __u32 uid, __u32 gid)
1804 {
1805         return yaffs_MknodObject(YAFFS_OBJECT_TYPE_DIRECTORY,parent,name,mode,uid,gid,NULL,NULL,0);
1806 }
1807
1808 yaffs_Object *yaffs_MknodSpecial(yaffs_Object *parent,const YCHAR *name, __u32 mode, __u32 uid, __u32 gid, __u32 rdev)
1809 {
1810         return yaffs_MknodObject(YAFFS_OBJECT_TYPE_SPECIAL,parent,name,mode,uid,gid,NULL,NULL,rdev);
1811 }
1812
1813 yaffs_Object *yaffs_MknodSymLink(yaffs_Object *parent,const YCHAR *name, __u32 mode, __u32 uid, __u32 gid,const YCHAR *alias)
1814 {
1815         return yaffs_MknodObject(YAFFS_OBJECT_TYPE_SYMLINK,parent,name,mode,uid,gid,NULL,alias,0);
1816 }
1817
1818 // NB yaffs_Link returns the object id of the equivalent object.
1819 yaffs_Object *yaffs_Link(yaffs_Object *parent, const YCHAR *name, yaffs_Object *equivalentObject)
1820 {
1821         // Get the real object in case we were fed a hard link as an equivalent object
1822         equivalentObject = yaffs_GetEquivalentObject(equivalentObject);
1823         
1824         if(yaffs_MknodObject(YAFFS_OBJECT_TYPE_HARDLINK,parent,name,0,0,0,equivalentObject,NULL,0))
1825         {
1826                 return equivalentObject;
1827         }
1828         else
1829         {
1830                 return NULL;
1831         }
1832         
1833 }
1834
1835
1836 static int yaffs_ChangeObjectName(yaffs_Object *obj, yaffs_Object *newDir, const YCHAR *newName,int force)
1837 {
1838         int unlinkOp;
1839         int deleteOp;
1840
1841         if(newDir == NULL)
1842         {
1843                 newDir = obj->parent; // use the old directory
1844         }
1845         
1846         if(newDir->variantType != YAFFS_OBJECT_TYPE_DIRECTORY)
1847         {
1848                 T(YAFFS_TRACE_ALWAYS,(TSTR("tragendy: yaffs_ChangeObjectName: newDir is not a directory"TENDSTR)));
1849                 YBUG();
1850         }
1851
1852         // TODO: Do we need this different handling for YAFFS2 and YAFFS1??
1853         if(obj->myDev->isYaffs2)
1854         {
1855                 unlinkOp = (newDir == obj->myDev->unlinkedDir);
1856         }
1857         else
1858         {
1859                 unlinkOp = (newDir == obj->myDev->unlinkedDir && obj->variantType == YAFFS_OBJECT_TYPE_FILE);
1860         }
1861
1862         deleteOp = (newDir == obj->myDev->deletedDir);
1863         
1864         // If the object is a file going into the unlinked directory, then it is OK to just stuff it in since
1865         // duplicate names are allowed.
1866         // Otherwise only proceed if the new name does not exist and if we're putting it into a directory.
1867         if( (unlinkOp|| 
1868                  deleteOp ||
1869                  force || 
1870                  !yaffs_FindObjectByName(newDir,newName))  &&
1871              newDir->variantType == YAFFS_OBJECT_TYPE_DIRECTORY)
1872         {
1873                 yaffs_SetObjectName(obj,newName);
1874                 obj->dirty = 1;
1875                 
1876                 yaffs_AddObjectToDirectory(newDir,obj);
1877                 
1878                 if(unlinkOp) obj->unlinked = 1;
1879                 
1880                 // If it is a deletion then we mark it as a shrink for gc purposes.
1881                 if(yaffs_UpdateObjectHeader(obj,newName,0,deleteOp) >= 0)
1882                 {
1883                         return YAFFS_OK;
1884                 }
1885         }
1886         
1887         return YAFFS_FAIL;
1888 }
1889
1890
1891
1892 int yaffs_RenameObject(yaffs_Object *oldDir, const YCHAR *oldName, yaffs_Object *newDir, const YCHAR *newName)
1893 {
1894         yaffs_Object *obj;
1895         int force = 0;
1896         
1897 #ifdef CONFIG_YAFFS_CASE_INSENSITIVE
1898         // Special case for case insemsitive systems (eg. WinCE).
1899         // While look-up is case insensitive, the name isn't.
1900         // THerefore we might want to change x.txt to X.txt
1901         if(oldDir == newDir && yaffs_strcmp(oldName,newName) == 0)
1902         {
1903                 force = 1;
1904         }       
1905 #endif
1906         
1907         obj = yaffs_FindObjectByName(oldDir,oldName);
1908         if(obj && obj->renameAllowed)
1909         {
1910                 return yaffs_ChangeObjectName(obj,newDir,newName,force);
1911         }
1912         return YAFFS_FAIL;
1913 }
1914
1915
1916 #if 0
1917
1918 static int yaffs_CheckObjectHashSanity(yaffs_Device *dev)
1919 {
1920         // Scan the buckets and check that the lists 
1921         // have as many members as the count says there are
1922         int bucket;
1923         int countEm;
1924         struct list_head *j;
1925         int ok = YAFFS_OK;
1926         
1927         for(bucket = 0; bucket < YAFFS_NOBJECT_BUCKETS; bucket++)
1928         {
1929                 countEm = 0;
1930                 
1931                 list_for_each(j,&dev->objectBucket[bucket].list)
1932                 {
1933                         countEm++;
1934                 }
1935                 
1936                 if(countEm != dev->objectBucket[bucket].count)
1937                 {
1938                         T(YAFFS_TRACE_ERROR,(TSTR("Inode hash inconsistency" TENDSTR)));
1939                         ok = YAFFS_FAIL;
1940                 }
1941         }
1942
1943         return ok;
1944 }
1945
1946
1947 void yaffs_ObjectTest(yaffs_Device *dev)
1948 {
1949         yaffs_Object *in[1000];
1950         int inNo[1000];
1951         yaffs_Object *inold[1000];
1952         int i;
1953         int j;
1954         
1955         memset(in,0,1000*sizeof(yaffs_Object *));
1956         memset(inold,0,1000*sizeof(yaffs_Object *));
1957         
1958         yaffs_CheckObjectHashSanity(dev);
1959         
1960         for(j = 0; j < 10; j++)
1961         {
1962                 //T(("%d\n",j));
1963                 
1964                 for(i = 0; i < 1000; i++)
1965                 {
1966                         in[i] = yaffs_CreateNewObject(dev,-1,YAFFS_OBJECT_TYPE_FILE);
1967                         if(!in[i])
1968                         {
1969                                 YINFO("No more inodes");
1970                         }
1971                         else
1972                         {
1973                                 inNo[i] = in[i]->objectId;
1974                         }
1975                 }
1976                 
1977                 for(i = 0; i < 1000; i++)
1978                 {
1979                         if(yaffs_FindObjectByNumber(dev,inNo[i]) != in[i])
1980                         {
1981                                 //T(("Differnce in look up test\n"));
1982                         }
1983                         else
1984                         {
1985                                 // T(("Look up ok\n"));
1986                         }
1987                 }
1988                 
1989                 yaffs_CheckObjectHashSanity(dev);
1990         
1991                 for(i = 0; i < 1000; i+=3)
1992                 {
1993                         yaffs_FreeObject(in[i]);        
1994                         in[i] = NULL;
1995                 }
1996                 
1997         
1998                 yaffs_CheckObjectHashSanity(dev);
1999         }
2000                 
2001 }
2002
2003 #endif
2004
2005 /////////////////////////// Block Management and Page Allocation ///////////////////
2006
2007
2008 static int yaffs_InitialiseBlocks(yaffs_Device *dev,int nBlocks)
2009 {
2010         dev->allocationBlock = -1; // force it to get a new one
2011         //Todo we're assuming the malloc will pass.
2012         dev->blockInfo = YMALLOC(nBlocks * sizeof(yaffs_BlockInfo));
2013         // Set up dynamic blockinfo stuff.
2014         dev->chunkBitmapStride = (dev->nChunksPerBlock+7)/8;
2015         dev->chunkBits = YMALLOC(dev->chunkBitmapStride * nBlocks);
2016         if(dev->blockInfo && dev->chunkBits)
2017         {
2018                 memset(dev->blockInfo,0,nBlocks * sizeof(yaffs_BlockInfo));
2019                 memset(dev->chunkBits,0,dev->chunkBitmapStride * nBlocks);
2020                 return YAFFS_OK;
2021         }
2022         
2023         return YAFFS_FAIL;
2024         
2025 }
2026
2027 static void yaffs_DeinitialiseBlocks(yaffs_Device *dev)
2028 {
2029         YFREE(dev->blockInfo);
2030         dev->blockInfo = NULL;
2031         YFREE(dev->chunkBits);
2032         dev->chunkBits = NULL;
2033 }
2034
2035
2036 static int yaffs_BlockNotDisqualifiedFromGC(yaffs_Device *dev, yaffs_BlockInfo *bi)
2037 {
2038         int i;
2039         __u32 seq;
2040         yaffs_BlockInfo *b;
2041         
2042         if(!dev->isYaffs2) return 1; // disqualification only applies to yaffs2.
2043         
2044         if(!bi->hasShrinkHeader) return 1; // can gc
2045
2046
2047         // Find the oldest dirty sequence number if we don't know it and save it
2048         // so we don't have to keep recomputing it.
2049         if(!dev->oldestDirtySequence)
2050         {
2051                 seq = dev->sequenceNumber;
2052
2053                 for(i = dev->internalStartBlock; i <= dev->internalEndBlock; i++)
2054                 {
2055                         b = yaffs_GetBlockInfo(dev,i);
2056                         if(b->blockState == YAFFS_BLOCK_STATE_FULL &&
2057                         (b->pagesInUse - b->softDeletions )< dev->nChunksPerBlock &&
2058                         b->sequenceNumber < seq)
2059                         {
2060                                 seq = b->sequenceNumber;
2061                         }
2062                 }
2063                 dev->oldestDirtySequence = seq;
2064         }
2065
2066
2067         // Can't do gc of this block if there are any blocks older than this one that have
2068         // discarded pages.
2069         return (bi->sequenceNumber <= dev->oldestDirtySequence);
2070         
2071         
2072         return 1;
2073
2074 }
2075
2076 // FindDiretiestBlock is used to select the dirtiest block (or close enough)
2077 // for garbage collection.
2078 //
2079
2080
2081
2082 static int yaffs_FindBlockForGarbageCollection(yaffs_Device *dev,int aggressive)
2083 {
2084
2085         int b = dev->currentDirtyChecker;
2086         
2087         int i;
2088         int iterations;
2089         int dirtiest = -1;
2090         int pagesInUse; 
2091         yaffs_BlockInfo *bi;
2092         static int  nonAggressiveSkip = 0;
2093
2094         // If we're doing aggressive GC then we are happy to take a less-dirty block, and
2095         // search harder.
2096         // else (we're doing a leasurely gc), then we only bother to do this if the
2097         // block has only a few pages in use.
2098         
2099
2100         nonAggressiveSkip--;
2101
2102         if(!aggressive &&(nonAggressiveSkip > 0))
2103         {
2104                 return -1;
2105         }
2106
2107         pagesInUse = (aggressive)? dev->nChunksPerBlock : YAFFS_PASSIVE_GC_CHUNKS + 1;
2108
2109         if(aggressive)
2110         {
2111                 iterations = dev->internalEndBlock - dev->internalStartBlock + 1;
2112         }
2113         else
2114         {
2115                 iterations = dev->internalEndBlock - dev->internalStartBlock + 1;
2116                 iterations = iterations / 16; 
2117                 if(iterations > 200)
2118                 {
2119                         iterations = 200;
2120                 }
2121         }
2122         
2123         for(i = 0; i <= iterations && pagesInUse > 0 ; i++)
2124         {
2125                 b++;
2126                 if ( b < dev->internalStartBlock || b > dev->internalEndBlock)
2127                 {
2128                         b =  dev->internalStartBlock;
2129                 }
2130
2131                 if(b < dev->internalStartBlock || b > dev->internalEndBlock)
2132                 {
2133                         T(YAFFS_TRACE_ERROR,(TSTR("**>> Block %d is not valid" TENDSTR),b));
2134                         YBUG();
2135                 }
2136                 
2137                 bi = yaffs_GetBlockInfo(dev,b);
2138                 
2139                 if(bi->blockState == YAFFS_BLOCK_STATE_FULL &&
2140                    (bi->pagesInUse - bi->softDeletions )< pagesInUse &&
2141                    yaffs_BlockNotDisqualifiedFromGC(dev,bi))
2142                 {
2143                         dirtiest = b;
2144                         pagesInUse = (bi->pagesInUse - bi->softDeletions);
2145                 }
2146         }
2147         
2148         dev->currentDirtyChecker = b;
2149         
2150         if(dirtiest > 0)
2151         {
2152                 T(YAFFS_TRACE_GC,(TSTR("GC Selected block %d with %d free" TENDSTR),dirtiest,dev->nChunksPerBlock - pagesInUse));
2153         }
2154         
2155         dev->oldestDirtySequence = 0; // clear this
2156         
2157         if(dirtiest > 0)
2158         {
2159                 nonAggressiveSkip = 4;
2160         }
2161
2162         return dirtiest;
2163 }
2164
2165
2166 static void yaffs_BlockBecameDirty(yaffs_Device *dev,int blockNo)
2167 {
2168         yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev,blockNo);
2169         
2170         int erasedOk = 0;
2171         
2172         // If the block is still healthy erase it and mark as clean.
2173         // If the block has had a data failure, then retire it.
2174         bi->blockState = YAFFS_BLOCK_STATE_DIRTY;
2175
2176         if(!bi->needsRetiring)
2177         {
2178                 erasedOk = yaffs_EraseBlockInNAND(dev,blockNo);
2179                 if(!erasedOk)
2180                 {
2181                         dev->nErasureFailures++;
2182                         T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,(TSTR("**>> Erasure failed %d" TENDSTR),blockNo));
2183                 }
2184         }
2185
2186         if(erasedOk && (yaffs_traceMask & YAFFS_TRACE_ERASE))
2187         {
2188                         int i;
2189                         for(i = 0; i < dev->nChunksPerBlock; i++)
2190                         {
2191                                         if(!yaffs_CheckChunkErased(dev,blockNo * dev->nChunksPerBlock + i))
2192                                         {
2193                                                 T(YAFFS_TRACE_ERROR,(TSTR(">>Block %d erasure supposedly OK, but chunk %d not erased" TENDSTR),blockNo,i));
2194                                         }
2195                         }
2196         }
2197         
2198         if( erasedOk )
2199         {
2200                 // Clean it up...
2201                 bi->blockState = YAFFS_BLOCK_STATE_EMPTY;
2202                 dev->nErasedBlocks++;
2203                 bi->pagesInUse = 0;
2204                 bi->softDeletions = 0;
2205                 bi->hasShrinkHeader=0;
2206                 yaffs_ClearChunkBits(dev,blockNo);
2207         
2208                 T(YAFFS_TRACE_ERASE,(TSTR("Erased block %d" TENDSTR),blockNo));
2209         }
2210         else
2211         {
2212                 dev->nFreeChunks -= dev->nChunksPerBlock; // We lost a block of free space
2213                 
2214                 yaffs_RetireBlock(dev,blockNo);
2215                 T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,(TSTR("**>> Block %d retired" TENDSTR),blockNo));
2216         }
2217 }
2218
2219 #if 0
2220 static void yaffs_DumpBlockStats(yaffs_Device *dev)
2221 {
2222         int i,j;
2223         yaffs_BlockInfo *bi;
2224         
2225         for(i= dev->internalStartBlock; i <=dev->internalEndBlock; i++)
2226         {
2227                 bi = yaffs_GetBlockInfo(dev,i);
2228                 T(YAFFS_TRACE_ALLOCATE,(TSTR("%3d state %d shrink %d inuse %d/%d seq %d pages"),i,
2229                 bi->blockState,bi->hasShrinkHeader,bi->pagesInUse,bi->softDeletions,bi->sequenceNumber));       
2230                 
2231                 for(j = 0; j < dev->nChunksPerBlock; j++)
2232                 {
2233                         if(yaffs_CheckChunkBit(dev,i,j))
2234                         {
2235                                 T(YAFFS_TRACE_ALLOCATE,(TSTR(" %d"),j));
2236
2237                         }
2238                 }
2239                 T(YAFFS_TRACE_ALLOCATE,(TSTR(" " TENDSTR)));
2240
2241         }
2242 }
2243 #endif
2244
2245
2246 static int yaffs_FindBlockForAllocation(yaffs_Device *dev)
2247 {
2248         int i;
2249         
2250         yaffs_BlockInfo *bi;
2251         
2252 #if 0
2253         static int j = 0;
2254         j++;
2255         if(j < 0 || j > 100)
2256         {
2257                 j = 0;
2258                 yaffs_DumpBlockStats(dev);
2259         }
2260         
2261 #endif
2262         
2263         if(dev->nErasedBlocks < 1)
2264         {
2265                 // Hoosterman we've got a problem.
2266                 // Can't get space to gc
2267                 T(YAFFS_TRACE_ERROR, (TSTR("yaffs tragedy: no more eraased blocks" TENDSTR)));
2268
2269                 return -1;
2270         }
2271         
2272         // Find an empty block.
2273         
2274         for(i = dev->internalStartBlock; i <= dev->internalEndBlock; i++)
2275         {
2276                 dev->allocationBlockFinder++;
2277                 if(dev->allocationBlockFinder < dev->internalStartBlock || dev->allocationBlockFinder> dev->internalEndBlock) 
2278                 {
2279                         dev->allocationBlockFinder = dev->internalStartBlock;
2280                 }
2281                 
2282                 bi = yaffs_GetBlockInfo(dev,dev->allocationBlockFinder);
2283
2284                 if(bi->blockState == YAFFS_BLOCK_STATE_EMPTY)
2285                 {
2286                         bi->blockState = YAFFS_BLOCK_STATE_ALLOCATING;
2287                         dev->sequenceNumber++;
2288                         bi->sequenceNumber = dev->sequenceNumber;
2289                         dev->nErasedBlocks--;           
2290                         T(YAFFS_TRACE_ALLOCATE,(TSTR("Allocated block %d, seq  %d, %d left" TENDSTR),dev->allocationBlockFinder,dev->sequenceNumber, dev->nErasedBlocks));      
2291                         return dev->allocationBlockFinder;
2292                 }
2293         }
2294         
2295         
2296         T(YAFFS_TRACE_ALWAYS, (TSTR("yaffs tragedy: no more eraased blocks, but there should have been %d" TENDSTR),dev->nErasedBlocks));
2297         
2298         
2299         
2300
2301         
2302         return -1;      
2303 }
2304
2305
2306 // To determine if we have enough space we just look at the 
2307 // number of erased blocks.
2308
2309 static int yaffs_CheckSpaceForAllocation(yaffs_Device *dev)
2310 {
2311         int reservedChunks = (dev->nReservedBlocks * dev->nChunksPerBlock);
2312         return (dev->nFreeChunks > reservedChunks);
2313 }
2314
2315
2316 static int yaffs_AllocateChunk(yaffs_Device *dev,int useReserve)
2317 {
2318         int retVal;
2319         yaffs_BlockInfo *bi;
2320         
2321         if(dev->allocationBlock < 0)
2322         {
2323                 // Get next block to allocate off
2324                 dev->allocationBlock = yaffs_FindBlockForAllocation(dev);
2325                 dev->allocationPage = 0;
2326         }
2327         
2328         if(!useReserve &&  !yaffs_CheckSpaceForAllocation(dev))
2329         {
2330                 // Not enough space to allocate unless we're allowed to use the reserve.
2331                 return -1;
2332         }
2333
2334         if(dev->nErasedBlocks < dev->nReservedBlocks && dev->allocationPage == 0)
2335         {
2336                 T(YAFFS_TRACE_ALLOCATE,(TSTR("Allocating reserve" TENDSTR)));   
2337         }
2338
2339         
2340         // Next page please....
2341         if(dev->allocationBlock >= 0)
2342         {
2343                 bi = yaffs_GetBlockInfo(dev,dev->allocationBlock);
2344                 
2345                 retVal = (dev->allocationBlock * dev->nChunksPerBlock) + 
2346                                   dev->allocationPage;
2347                 bi->pagesInUse++;
2348                 yaffs_SetChunkBit(dev,dev->allocationBlock,dev->allocationPage);
2349
2350                 dev->allocationPage++;
2351                 
2352                 dev->nFreeChunks--;
2353                 
2354                 // If the block is full set the state to full
2355                 if(dev->allocationPage >= dev->nChunksPerBlock)
2356                 {
2357                         bi->blockState = YAFFS_BLOCK_STATE_FULL;
2358                         dev->allocationBlock = -1;
2359                 }
2360
2361
2362                 return retVal;
2363                 
2364         }
2365         T(YAFFS_TRACE_ERROR,(TSTR("!!!!!!!!! Allocator out !!!!!!!!!!!!!!!!!" TENDSTR)));
2366
2367         return -1;      
2368 }
2369
2370
2371
2372
2373 static int yaffs_GetErasedChunks(yaffs_Device *dev)
2374 {
2375                 int n;
2376
2377                 n = dev->nErasedBlocks * dev->nChunksPerBlock;
2378
2379                 if(dev->allocationBlock> 0)
2380                 {
2381                         n += (dev->nChunksPerBlock - dev->allocationPage);
2382                 }
2383
2384                 return n;
2385
2386 }
2387
2388 int  yaffs_GarbageCollectBlock(yaffs_Device *dev,int block)
2389 {
2390         int oldChunk;
2391         int newChunk;
2392         int chunkInBlock;
2393         int markNAND;
2394         int retVal = YAFFS_OK;
2395         int cleanups = 0;
2396         int i;
2397
2398         int chunksBefore = yaffs_GetErasedChunks(dev);
2399         int chunksAfter;
2400
2401         yaffs_ExtendedTags  tags;
2402         
2403         yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev,block);
2404         
2405         yaffs_Object *object;
2406         
2407         bi->blockState = YAFFS_BLOCK_STATE_COLLECTING;
2408
2409         T(YAFFS_TRACE_TRACING,(TSTR("Collecting block %d, in use %d, shrink %d, " TENDSTR),block,bi->pagesInUse,bi->hasShrinkHeader));
2410         //T(("Collecting block %d n %d bits %x\n",block, bi->pagesInUse, bi->pageBits));        
2411         
2412         //yaffs_VerifyFreeChunks(dev);
2413
2414         bi->hasShrinkHeader = 0; // clear the flag so that the block can erase
2415         
2416         dev->nFreeChunks -= bi->softDeletions;  // Take off the number of soft deleted entries because
2417                                                 // they're going to get really deleted during GC.
2418
2419         dev->isDoingGC = 1;
2420
2421         if(!yaffs_StillSomeChunkBits(dev,block))
2422         {
2423                 T(YAFFS_TRACE_TRACING,(TSTR("Collecting block %d that has no chunks in use" TENDSTR),block));
2424                 yaffs_BlockBecameDirty(dev,block);
2425         }
2426         else
2427         {
2428
2429         __u8  *buffer = yaffs_GetTempBuffer(dev,__LINE__);
2430
2431         for(chunkInBlock = 0,oldChunk = block * dev->nChunksPerBlock; 
2432             chunkInBlock < dev->nChunksPerBlock && yaffs_StillSomeChunkBits(dev,block);
2433             chunkInBlock++, oldChunk++ )
2434         {
2435                 if(yaffs_CheckChunkBit(dev,block,chunkInBlock))
2436                 {
2437                         
2438                         // This page is in use and might need to be copied off
2439                         
2440                         markNAND = 1;
2441                         
2442                         //T(("copying page %x from %d to %d\n",mask,oldChunk,newChunk));
2443                         
2444                         yaffs_InitialiseTags(&tags);
2445                         
2446                         yaffs_ReadChunkWithTagsFromNAND(dev,oldChunk,buffer, &tags);
2447
2448                         object = yaffs_FindObjectByNumber(dev,tags.objectId);
2449                         
2450                         T(YAFFS_TRACE_GC_DETAIL,(TSTR("Collecting page %d, %d %d %d " TENDSTR),chunkInBlock,tags.objectId,tags.chunkId,tags.byteCount));
2451                         
2452                         if(!object)
2453                         {
2454                                 T(YAFFS_TRACE_ERROR,(TSTR("page %d in gc has no object " TENDSTR),oldChunk));
2455                         }
2456                         
2457                         if(object && object->deleted && tags.chunkId != 0)
2458                         {
2459                                 // Data chunk in a deleted file, throw it away
2460                                 // It's a soft deleted data chunk,
2461                                 // No need to copy this, just forget about it and fix up the
2462                                 // object.
2463                                 
2464                                 //yaffs_PutChunkIntoFile(object, tags.chunkId, 0,0); 
2465                                 object->nDataChunks--;
2466                                 
2467                                 if(object->nDataChunks <= 0)
2468                                 {
2469                                         // remeber to clean up the object
2470                                         dev->gcCleanupList[cleanups] = tags.objectId;
2471                                         cleanups++;
2472                                 }
2473                                 markNAND = 0;
2474                         }
2475                         else if( 0 /* Todo object && object->deleted && object->nDataChunks == 0 */)
2476                         {
2477                                 // Deleted object header with no data chunks.
2478                                 // Can be discarded and the file deleted.
2479                                 object->chunkId = 0;
2480                                 yaffs_FreeTnode(object->myDev,object->variant.fileVariant.top);
2481                                 object->variant.fileVariant.top = NULL;
2482                                 yaffs_DoGenericObjectDeletion(object);
2483                                 
2484                         }
2485                         else if(object)
2486                         {
2487                                 // It's either a data chunk in a live file or
2488                                 // an ObjectHeader, so we're interested in it.
2489                                 // NB Need to keep the ObjectHeaders of deleted files
2490                                 // until the whole file has been deleted off
2491                                 tags.serialNumber++;
2492
2493                                 dev->nGCCopies++;
2494
2495                                 newChunk = yaffs_WriteNewChunkWithTagsToNAND(dev, buffer, &tags,1);
2496                         
2497                                 if(newChunk < 0)
2498                                 {
2499                                         retVal =  YAFFS_FAIL;
2500                                 }
2501                                 else
2502                                 {
2503                         
2504                                         // Ok, now fix up the Tnodes etc.
2505                         
2506                                         if(tags.chunkId == 0)
2507                                         {
2508                                                 // It's a header
2509                                                 object->chunkId = newChunk;
2510                                                 object->serial = tags.serialNumber;
2511                                         }
2512                                         else
2513                                         {
2514                                                 // It's a data chunk
2515                                                 yaffs_PutChunkIntoFile(object, tags.chunkId, newChunk,0);
2516                                         }
2517                                 }
2518                         }
2519                         
2520                         yaffs_DeleteChunk(dev,oldChunk,markNAND,__LINE__);                      
2521                         
2522                 }
2523         }
2524
2525         yaffs_ReleaseTempBuffer(dev,buffer,__LINE__);
2526
2527         //yaffs_VerifyFreeChunks(dev);
2528
2529         // Do any required cleanups
2530         for(i = 0; i < cleanups; i++)
2531         {                                               
2532                 // Time to delete the file too
2533                 object =  yaffs_FindObjectByNumber(dev,dev->gcCleanupList[i]);
2534                 if(object)
2535                 {
2536                         yaffs_FreeTnode(dev,object->variant.fileVariant.top);
2537                         object->variant.fileVariant.top = NULL;
2538                         T(YAFFS_TRACE_GC,(TSTR("yaffs: About to finally delete object %d" TENDSTR),object->objectId));
2539                         yaffs_DoGenericObjectDeletion(object);
2540                 }
2541
2542         }
2543
2544         }
2545
2546         if(chunksBefore >= (chunksAfter = yaffs_GetErasedChunks(dev)))
2547         {
2548                         T(YAFFS_TRACE_GC,(TSTR("gc did not increase free chunks before %d after %d" TENDSTR),chunksBefore,chunksAfter));
2549         }
2550         
2551         
2552         dev->isDoingGC = 0;
2553         
2554         //yaffs_VerifyFreeChunks(dev);
2555                         
2556         return YAFFS_OK;
2557 }
2558
2559 #if 0
2560 static yaffs_Object *yaffs_FindDeletedUnlinkedFile(yaffs_Device *dev)
2561 {
2562         // find a file to delete
2563         struct list_head *i;    
2564         yaffs_Object *l;
2565
2566
2567         //Scan the unlinked files looking for one to delete
2568         list_for_each(i,&dev->unlinkedDir->variant.directoryVariant.children)
2569         {
2570                 if(i)
2571                 {
2572                         l = list_entry(i, yaffs_Object,siblings);
2573                         if(l->deleted)
2574                         {
2575                                 return l;                       
2576                         }
2577                 }
2578         }       
2579         return NULL;
2580 }
2581
2582
2583 static void yaffs_DoUnlinkedFileDeletion(yaffs_Device *dev)
2584 {
2585         // This does background deletion on unlinked files.. only deleted ones.
2586         // If we don't have a file we're working on then find one
2587         if(!dev->unlinkedDeletion && dev->nDeletedFiles > 0)
2588         {
2589                 dev->unlinkedDeletion = yaffs_FindDeletedUnlinkedFile(dev);
2590         }
2591         
2592         // OK, we're working on a file...
2593         if(dev->unlinkedDeletion)
2594         {
2595                 yaffs_Object *obj = dev->unlinkedDeletion;
2596                 int delresult;
2597                 int limit; // Number of chunks to delete in a file.
2598                                    // NB this can be exceeded, but not by much.
2599                                    
2600                 limit = -1;
2601
2602                 delresult = yaffs_DeleteWorker(obj, obj->variant.fileVariant.top, obj->variant.fileVariant.topLevel, 0,&limit);
2603                 
2604                 if(obj->nDataChunks == 0)
2605                 {
2606                         // Done all the deleting of data chunks.
2607                         // Now dump the header and clean up
2608                         yaffs_FreeTnode(dev,obj->variant.fileVariant.top);
2609                         obj->variant.fileVariant.top = NULL;
2610                         yaffs_DoGenericObjectDeletion(obj);
2611                         dev->nDeletedFiles--;
2612                         dev->nUnlinkedFiles--;
2613                         dev->nBackgroundDeletions++;
2614                         dev->unlinkedDeletion = NULL;   
2615                 }
2616         }
2617 }
2618
2619 #endif
2620
2621
2622
2623 // New garbage collector
2624 // If we're very low on erased blocks then we do aggressive garbage collection
2625 // otherwise we do "leasurely" garbage collection.
2626 // Aggressive gc looks further (whole array) and will accept dirtier blocks.
2627 // Passive gc only inspects smaller areas and will only accept cleaner blocks.
2628 //
2629 // The idea is to help clear out space in a more spread-out manner.
2630 // Dunno if it really does anything useful.
2631 //
2632 int yaffs_CheckGarbageCollection(yaffs_Device *dev)
2633 {
2634         int block;
2635         int aggressive; 
2636         int gcOk = YAFFS_OK;
2637         int maxTries = 0;
2638         
2639         //yaffs_VerifyFreeChunks(dev);
2640         
2641         if(dev->isDoingGC)
2642         {
2643                 // Bail out so we don't get recursive gc
2644                 return YAFFS_OK;
2645         }
2646
2647         // This loop should pass the first time.
2648         // We'll only see looping here if the erase of the collected block fails.
2649         
2650         do{
2651                 maxTries++;
2652                 if(dev->nErasedBlocks < dev->nReservedBlocks)
2653                 {
2654                         // We need a block soon...
2655                         aggressive = 1;
2656                 }
2657                 else 
2658                 {
2659                         // We're in no hurry
2660                         aggressive = 0;
2661                 }
2662         
2663                 block = yaffs_FindBlockForGarbageCollection(dev,aggressive);
2664         
2665                 if(block > 0)
2666                 {
2667                         dev->garbageCollections++;
2668                         if(!aggressive)
2669                         {
2670                                 dev->passiveGarbageCollections++;
2671                         }
2672
2673                         T(YAFFS_TRACE_GC,(TSTR("yaffs: GC erasedBlocks %d aggressive %d" TENDSTR),dev->nErasedBlocks,aggressive));
2674
2675                         gcOk =  yaffs_GarbageCollectBlock(dev,block);
2676                 }
2677
2678                 if(dev->nErasedBlocks < (dev->nReservedBlocks) && block > 0) 
2679                 {
2680                         T(YAFFS_TRACE_GC,(TSTR("yaffs: GC !!!no reclaim!!! erasedBlocks %d after try %d block %d" TENDSTR),dev->nErasedBlocks,maxTries,block));
2681                 }
2682         } while((dev->nErasedBlocks < dev->nReservedBlocks) && (block > 0) && (maxTries < 2));
2683
2684         return aggressive ? gcOk: YAFFS_OK;
2685 }
2686
2687
2688 //////////////////////////// TAGS ///////////////////////////////////////
2689
2690
2691
2692 #if 0
2693
2694 void yaffs_CalcTagsECC(yaffs_Tags *tags)
2695 {
2696         // Calculate an ecc
2697         
2698         unsigned char *b = ((yaffs_TagsUnion *)tags)->asBytes;
2699         unsigned  i,j;
2700         unsigned  ecc = 0;
2701         unsigned bit = 0;
2702
2703         tags->ecc = 0;
2704         
2705         for(i = 0; i < 8; i++)
2706         {
2707                 for(j = 1; j &0xff; j<<=1)
2708                 {
2709                         bit++;
2710                         if(b[i] & j)
2711                         {
2712                                 ecc ^= bit;
2713                         }
2714                 }
2715         }
2716         
2717         tags->ecc = ecc;
2718         
2719         
2720 }
2721
2722 int  yaffs_CheckECCOnTags(yaffs_Tags *tags)
2723 {
2724         unsigned ecc = tags->ecc;
2725         
2726         yaffs_CalcTagsECC(tags);
2727         
2728         ecc ^= tags->ecc;
2729         
2730         if(ecc && ecc <= 64)
2731         {
2732                 // TODO: Handle the failure better. Retire?
2733                 unsigned char *b = ((yaffs_TagsUnion *)tags)->asBytes;
2734
2735                 ecc--;
2736                                 
2737                 b[ecc / 8] ^= (1 << (ecc & 7));
2738                 
2739                 // Now recvalc the ecc
2740                 yaffs_CalcTagsECC(tags);
2741                 
2742                 return 1; // recovered error
2743         }
2744         else if(ecc)
2745         {
2746                 // Wierd ecc failure value
2747                 // TODO Need to do somethiong here
2748                 return -1; //unrecovered error
2749         }
2750         
2751         return 0;
2752 }
2753
2754 static void yaffs_LoadTagsIntoSpare(yaffs_Spare *sparePtr, yaffs_Tags *tagsPtr)
2755 {
2756         yaffs_TagsUnion *tu = (yaffs_TagsUnion *)tagsPtr;
2757         
2758         yaffs_CalcTagsECC(tagsPtr);
2759         
2760         sparePtr->tagByte0 = tu->asBytes[0];
2761         sparePtr->tagByte1 = tu->asBytes[1];
2762         sparePtr->tagByte2 = tu->asBytes[2];
2763         sparePtr->tagByte3 = tu->asBytes[3];
2764         sparePtr->tagByte4 = tu->asBytes[4];
2765         sparePtr->tagByte5 = tu->asBytes[5];
2766         sparePtr->tagByte6 = tu->asBytes[6];
2767         sparePtr->tagByte7 = tu->asBytes[7];
2768 }
2769
2770 static void yaffs_GetTagsFromSpare(yaffs_Device *dev, yaffs_Spare *sparePtr,yaffs_Tags *tagsPtr)
2771 {
2772         yaffs_TagsUnion *tu = (yaffs_TagsUnion *)tagsPtr;
2773         int result;
2774
2775         tu->asBytes[0]= sparePtr->tagByte0;
2776         tu->asBytes[1]= sparePtr->tagByte1;
2777         tu->asBytes[2]= sparePtr->tagByte2;
2778         tu->asBytes[3]= sparePtr->tagByte3;
2779         tu->asBytes[4]= sparePtr->tagByte4;
2780         tu->asBytes[5]= sparePtr->tagByte5;
2781         tu->asBytes[6]= sparePtr->tagByte6;
2782         tu->asBytes[7]= sparePtr->tagByte7;
2783         
2784         result =  yaffs_CheckECCOnTags(tagsPtr);
2785         if(result> 0)
2786         {
2787                 dev->tagsEccFixed++;
2788         }
2789         else if(result <0)
2790         {
2791                 dev->tagsEccUnfixed++;
2792         }
2793 }
2794
2795 static void yaffs_SpareInitialise(yaffs_Spare *spare)
2796 {
2797         memset(spare,0xFF,sizeof(yaffs_Spare));
2798 }
2799
2800 #endif
2801
2802 #if 0
2803 static int yaffs_WriteNewChunkWithTagsToNAND(yaffs_Device *dev, const __u8 *buffer, yaffs_ExtendedTags *tags, int useReserve)
2804 {
2805         // NB There must be tags, data is optional
2806         // If there is data, then an ECC is calculated on it.
2807         
2808         yaffs_Spare spare;
2809         
2810         if(!tags)
2811         {
2812                 return YAFFS_FAIL;
2813         }
2814         
2815         //yaffs_SpareInitialise(&spare);
2816         
2817         //if(!dev->useNANDECC && buffer)
2818         //{
2819         //      yaffs_CalcECC(buffer,&spare);
2820         //}
2821         
2822         //yaffs_LoadTagsIntoSpare(&spare,tags);
2823         
2824         return yaffs_WriteNewChunkToNAND(dev,buffer,&spare,useReserve);
2825         
2826 }
2827 #endif
2828
2829 static int yaffs_TagsMatch(const yaffs_ExtendedTags *tags, int objectId, int chunkInObject)
2830 {
2831         return  (  tags->chunkId == chunkInObject &&
2832                            tags->objectId == objectId &&
2833                            !tags->chunkDeleted) ? 1 : 0;
2834         
2835 }
2836
2837 /////////////////////////////////////////////////////////////////////////////////////////////////////////
2838
2839
2840 int yaffs_FindChunkInFile(yaffs_Object *in,int chunkInInode,yaffs_ExtendedTags *tags)
2841 {
2842         //Get the Tnode, then get the level 0 offset chunk offset
2843     yaffs_Tnode *tn;     
2844     int theChunk = -1;
2845     yaffs_ExtendedTags localTags;
2846     int retVal = -1;
2847     
2848     yaffs_Device *dev = in->myDev;
2849     
2850     
2851     if(!tags)
2852     {
2853         // Passed a NULL, so use our own tags space
2854         tags = &localTags;
2855     }
2856     
2857     tn = yaffs_FindLevel0Tnode(dev,&in->variant.fileVariant, chunkInInode);
2858     
2859     if(tn)
2860     {
2861                 theChunk = tn->level0[chunkInInode & YAFFS_TNODES_LEVEL0_MASK] << dev->chunkGroupBits;
2862                 
2863                 retVal = yaffs_FindChunkInGroup(dev,theChunk,tags,in->objectId,chunkInInode);
2864     }
2865     return retVal;
2866 }
2867
2868 int yaffs_FindAndDeleteChunkInFile(yaffs_Object *in,int chunkInInode,yaffs_ExtendedTags *tags)
2869 {
2870         //Get the Tnode, then get the level 0 offset chunk offset
2871     yaffs_Tnode *tn;     
2872     int theChunk = -1;
2873     yaffs_ExtendedTags localTags;
2874
2875     yaffs_Device *dev = in->myDev;
2876     int retVal = -1;
2877     
2878     if(!tags)
2879     {
2880         // Passed a NULL, so use our own tags space
2881         tags = &localTags;
2882     }
2883     
2884     tn = yaffs_FindLevel0Tnode(dev,&in->variant.fileVariant, chunkInInode);
2885     
2886     if(tn)
2887     {
2888     
2889                 theChunk = tn->level0[chunkInInode & YAFFS_TNODES_LEVEL0_MASK] << dev->chunkGroupBits;
2890                 
2891                 retVal = yaffs_FindChunkInGroup(dev,theChunk,tags,in->objectId,chunkInInode);
2892     
2893                 // Delete the entry in the filestructure (if found)
2894                 if(retVal != -1)
2895                 {
2896                         tn->level0[chunkInInode & YAFFS_TNODES_LEVEL0_MASK] = 0;
2897                 }
2898     }
2899     else
2900     {
2901         //T(("No level 0 found for %d\n", chunkInInode));
2902     }
2903     
2904     if(retVal == -1)
2905     {
2906         //T(("Could not find %d to delete\n",chunkInInode));
2907     }
2908     return retVal;
2909 }
2910
2911
2912 #ifdef YAFFS_PARANOID
2913
2914 static int yaffs_CheckFileSanity(yaffs_Object *in)
2915 {
2916         int chunk;
2917         int nChunks;
2918         int fSize;
2919         int failed = 0;
2920         int objId;
2921         yaffs_Tnode *tn;
2922     yaffs_Tags localTags;
2923     yaffs_Tags *tags = &localTags;
2924     int theChunk;
2925     int chunkDeleted;
2926     
2927         
2928         if(in->variantType != YAFFS_OBJECT_TYPE_FILE)
2929         {
2930                 //T(("Object not a file\n"));
2931                 return YAFFS_FAIL;
2932         }
2933         
2934         objId = in->objectId;
2935         fSize  = in->variant.fileVariant.fileSize;
2936         nChunks = (fSize + in->myDev->nBytesPerChunk -1)/in->myDev->nBytesPerChunk;
2937         
2938         for(chunk = 1; chunk <= nChunks; chunk++)
2939         {
2940                 tn = yaffs_FindLevel0Tnode(in->myDev,&in->variant.fileVariant, chunk);
2941     
2942                 if(tn)
2943                 {
2944     
2945                         theChunk = tn->level0[chunk & YAFFS_TNODES_LEVEL0_MASK] << in->myDev->chunkGroupBits;
2946                         
2947                 if(yaffs_CheckChunkBits(dev,theChunk/dev->nChunksPerBlock,theChunk%dev->nChunksPerBlock))
2948                         {
2949
2950
2951                                 yaffs_ReadChunkTagsFromNAND(in->myDev,theChunk,tags,&chunkDeleted);
2952                                 if(yaffs_TagsMatch(tags,in->objectId,chunk,chunkDeleted))
2953                                 {
2954                                         // found it;
2955                                 
2956                                 }
2957                         }
2958                         else
2959                         {
2960                                 //T(("File problem file [%d,%d] NAND %d  tags[%d,%d]\n",
2961                                 //              objId,chunk,theChunk,tags->chunkId,tags->objectId);
2962                                                 
2963                                 failed = 1;
2964                                                         
2965                         }
2966     
2967                 }
2968                 else
2969                 {
2970                         //T(("No level 0 found for %d\n", chunk));
2971                 }
2972         }
2973         
2974         return failed ? YAFFS_FAIL : YAFFS_OK;
2975 }
2976
2977 #endif
2978
2979 static int yaffs_PutChunkIntoFile(yaffs_Object *in,int chunkInInode, int chunkInNAND, int inScan)
2980 {
2981         // NB inScan is zero unless scanning. For forward scanning, inScan is > 0; for backward scanning inScan is < 0
2982         yaffs_Tnode *tn;
2983         yaffs_Device *dev = in->myDev;
2984         int existingChunk;
2985         yaffs_ExtendedTags existingTags;
2986         yaffs_ExtendedTags newTags;
2987         unsigned existingSerial, newSerial;
2988         
2989         if(in->variantType != YAFFS_OBJECT_TYPE_FILE)
2990         {
2991                 // Just ignore an attempt at putting a chunk into a non-file during scanning
2992                 // If it is not during Scanning then something went wrong!
2993                 if(!inScan)
2994                 {
2995                         T(YAFFS_TRACE_ERROR, (TSTR("yaffs tragedy:attempt to put data chunk into a non-file" TENDSTR)));
2996                         YBUG();
2997                 }
2998                 
2999                 yaffs_DeleteChunk(dev,chunkInNAND,1,__LINE__);
3000                 return YAFFS_OK;
3001         }
3002                 
3003         tn = yaffs_AddOrFindLevel0Tnode(dev,&in->variant.fileVariant, chunkInInode);
3004         if(!tn)
3005         {
3006                 return YAFFS_FAIL;
3007         }
3008
3009         existingChunk = tn->level0[chunkInInode & YAFFS_TNODES_LEVEL0_MASK];            
3010         
3011         if(inScan != 0)
3012         {
3013                 // If we're scanning then we need to test for duplicates
3014                 // NB This does not need to be efficient since it should only ever 
3015                 // happen when the power fails during a write, then only one
3016                 // chunk should ever be affected.
3017                 //
3018                 // Correction for YAFFS2: This could happen quite a lot and we need to think about efficiency! TODO
3019                 // Update: For backward scanning we don't need to re-read tags so this is quite cheap.
3020                 
3021         
3022                 
3023                 if(existingChunk != 0)
3024                 {
3025                         // NB Right now existing chunk will not be real chunkId if the device >= 32MB
3026                         //    thus we have to do a FindChunkInFile to get the real chunk id.
3027                         //
3028                         // We have a duplicate now we need to decide which one to use:
3029                         //
3030                         // Backwards scanning YAFFS2: The old one is what we use, dump the new one.
3031                         // Forward scanning YAFFS2: The new one is what we use, dump the old one.
3032                         // YAFFS1: Get both sets of tags and compare serial numbers.
3033                         //
3034                         //
3035                         
3036                         if(inScan > 0)
3037                         {
3038                                 // Only do this for forward scanning
3039                                 yaffs_ReadChunkWithTagsFromNAND(dev,chunkInNAND, NULL,&newTags);
3040                         
3041                         
3042                                 // Do a proper find
3043                                 existingChunk = yaffs_FindChunkInFile(in,chunkInInode, &existingTags);
3044                         }
3045
3046                         if(existingChunk <=0)
3047                         {
3048                                 //Hoosterman - how did this happen?
3049                                 
3050                                 T(YAFFS_TRACE_ERROR, (TSTR("yaffs tragedy: existing chunk < 0 in scan" TENDSTR)));
3051
3052                         }
3053
3054                         
3055                         // NB The deleted flags should be false, otherwise the chunks will 
3056                         // not be loaded during a scan
3057                         
3058                         newSerial = newTags.serialNumber;
3059                         existingSerial = existingTags.serialNumber;
3060                         
3061                         if( (inScan > 0) &&
3062                             ( in->myDev->isYaffs2  ||
3063                               existingChunk <= 0 ||
3064                              ((existingSerial+1) & 3) == newSerial))
3065                         {
3066                                 // Forward scanning.                            
3067                                 // Use new
3068                                 // Delete the old one and drop through to update the tnode
3069                                 yaffs_DeleteChunk(dev,existingChunk,1,__LINE__);
3070                         }
3071                         else
3072                         {
3073                                 // Backward scanning or we want to use the existing one
3074                                 // Use existing.
3075                                 // Delete the new one and return early so that the tnode isn't changed
3076                                 yaffs_DeleteChunk(dev,chunkInNAND,1,__LINE__);
3077                                 return YAFFS_OK;
3078                         }
3079                 }
3080
3081         }
3082                 
3083         if(existingChunk == 0)
3084         {
3085                 in->nDataChunks++;
3086         }
3087         
3088         tn->level0[chunkInInode & YAFFS_TNODES_LEVEL0_MASK] = (chunkInNAND >> dev->chunkGroupBits);
3089         
3090         return YAFFS_OK;
3091 }
3092
3093
3094
3095 int yaffs_ReadChunkDataFromObject(yaffs_Object *in,int chunkInInode, __u8 *buffer)
3096 {
3097     int chunkInNAND = yaffs_FindChunkInFile(in,chunkInInode,NULL);
3098     
3099     if(chunkInNAND >= 0)
3100     {
3101                 return yaffs_ReadChunkWithTagsFromNAND(in->myDev,chunkInNAND,buffer,NULL);
3102         }
3103         else
3104         {
3105                 T(YAFFS_TRACE_NANDACCESS,(TSTR("Chunk %d not found zero instead" TENDSTR),chunkInNAND));
3106
3107                 memset(buffer,0,in->myDev->nBytesPerChunk); // get sane data if you read a hole
3108                 return 0;
3109         }
3110
3111 }
3112
3113
3114 void yaffs_DeleteChunk(yaffs_Device *dev,int chunkId,int markNAND,int lyn)
3115 {
3116         int block;
3117         int page;
3118         yaffs_ExtendedTags tags;
3119         yaffs_BlockInfo *bi;
3120         
3121         if(chunkId <= 0) return;        
3122         
3123         dev->nDeletions++;
3124         block = chunkId / dev->nChunksPerBlock;
3125         page = chunkId % dev->nChunksPerBlock;
3126         
3127         bi = yaffs_GetBlockInfo(dev,block);
3128         
3129         T(YAFFS_TRACE_DELETION,(TSTR("line %d delete of chunk %d" TENDSTR),lyn,chunkId));
3130         
3131         if(markNAND && 
3132           bi->blockState != YAFFS_BLOCK_STATE_COLLECTING &&
3133           !dev->isYaffs2)
3134         {
3135 //              yaffs_SpareInitialise(&spare);
3136
3137 #ifdef CONFIG_MTD_NAND_VERIFY_WRITE
3138
3139                 //read data before write, to ensure correct ecc 
3140                 //if we're using MTD verification under Linux
3141                 yaffs_ReadChunkFromNAND(dev,chunkId,NULL,&spare,0);
3142 #endif
3143
3144                 yaffs_InitialiseTags(&tags);
3145
3146                 tags.chunkDeleted = 1;
3147
3148         
3149                 yaffs_WriteChunkWithTagsToNAND(dev,chunkId,NULL,&tags);
3150                 yaffs_HandleUpdateChunk(dev,chunkId,&tags);
3151         }
3152         else
3153         {
3154                         dev->nUnmarkedDeletions++;
3155         }       
3156         
3157         
3158         // Pull out of the management area.
3159         // If the whole block became dirty, this will kick off an erasure.
3160         if(     bi->blockState == YAFFS_BLOCK_STATE_ALLOCATING ||
3161             bi->blockState == YAFFS_BLOCK_STATE_FULL ||     
3162             bi->blockState == YAFFS_BLOCK_STATE_NEEDS_SCANNING ||
3163             bi->blockState == YAFFS_BLOCK_STATE_COLLECTING)
3164         {
3165                 dev->nFreeChunks++;
3166
3167                 yaffs_ClearChunkBit(dev,block,page);
3168                 
3169                 bi->pagesInUse--;
3170                 
3171                 if(bi->pagesInUse == 0 &&
3172                    !bi->hasShrinkHeader &&
3173                bi->blockState != YAFFS_BLOCK_STATE_ALLOCATING &&
3174                bi->blockState != YAFFS_BLOCK_STATE_NEEDS_SCANNING)
3175             {
3176                 yaffs_BlockBecameDirty(dev,block);
3177             }
3178
3179         }
3180         else
3181         {
3182                 // T(("Bad news deleting chunk %d\n",chunkId));
3183         }
3184         
3185 }
3186
3187
3188
3189
3190 int yaffs_WriteChunkDataToObject(yaffs_Object *in,int chunkInInode, const __u8 *buffer,int nBytes,int useReserve)
3191 {
3192         // Find old chunk Need to do this to get serial number
3193         // Write new one and patch into tree.
3194         // Invalidate old tags.
3195
3196     int prevChunkId;
3197     yaffs_ExtendedTags prevTags;
3198     
3199     int newChunkId;
3200     yaffs_ExtendedTags newTags;
3201
3202     yaffs_Device *dev = in->myDev;    
3203
3204         yaffs_CheckGarbageCollection(dev);
3205
3206         // Get the previous chunk at this location in the file if it exists
3207     prevChunkId  = yaffs_FindChunkInFile(in,chunkInInode,&prevTags);
3208     
3209     // Set up new tags
3210     yaffs_InitialiseTags(&newTags);
3211     
3212         newTags.chunkId = chunkInInode;
3213         newTags.objectId = in->objectId;
3214         newTags.serialNumber = (prevChunkId >= 0) ? prevTags.serialNumber + 1 : 1;
3215         newTags.byteCount = nBytes;
3216                 
3217 //      yaffs_CalcTagsECC(&newTags);
3218
3219         newChunkId = yaffs_WriteNewChunkWithTagsToNAND(dev,buffer,&newTags,useReserve);
3220         
3221         if(newChunkId >= 0)
3222         {
3223                 yaffs_PutChunkIntoFile(in,chunkInInode,newChunkId,0);
3224                 
3225                 
3226                 if(prevChunkId >= 0)
3227                 {
3228                         yaffs_DeleteChunk(dev,prevChunkId,1,__LINE__);
3229         
3230                 }
3231                 
3232                 yaffs_CheckFileSanity(in);
3233         }
3234         return newChunkId;
3235
3236
3237
3238
3239
3240 }
3241
3242
3243 // UpdateObjectHeader updates the header on NAND for an object.
3244 // If name is not NULL, then that new name is used.
3245 //
3246 int yaffs_UpdateObjectHeader(yaffs_Object *in,const YCHAR *name, int force,int isShrink)
3247 {
3248
3249         yaffs_BlockInfo *bi;
3250         
3251         yaffs_Device *dev = in->myDev;
3252         
3253     int prevChunkId;
3254     int retVal = 0;
3255     
3256     int newChunkId;
3257     yaffs_ExtendedTags newTags;
3258     
3259     __u8 *buffer = NULL;
3260     YCHAR oldName[YAFFS_MAX_NAME_LENGTH+1];
3261     
3262    // __u8 bufferOld[YAFFS_BYTES_PER_CHUNK];
3263     
3264     yaffs_ObjectHeader *oh = NULL;
3265     // yaffs_ObjectHeader *ohOld = (yaffs_ObjectHeader *)bufferOld;
3266
3267     
3268     if(!in->fake || force)
3269     {
3270   
3271                 yaffs_CheckGarbageCollection(dev);              
3272     
3273             buffer = yaffs_GetTempBuffer(in->myDev,__LINE__);
3274             oh  = (yaffs_ObjectHeader *)buffer;
3275     
3276                 prevChunkId = in->chunkId;
3277     
3278                 if(prevChunkId >= 0)
3279                 {
3280                         yaffs_ReadChunkWithTagsFromNAND(dev,prevChunkId,buffer,NULL);
3281                         memcpy(oldName,oh->name,sizeof(oh->name));      
3282                 }
3283
3284                 memset(buffer,0xFF,dev->nBytesPerChunk);
3285
3286                 // Header data
3287                 oh->type = in->variantType;
3288                 
3289                 oh->yst_mode = in->yst_mode;
3290
3291 #ifdef CONFIG_YAFFS_WINCE
3292                 oh->win_atime[0] = in->win_atime[0];
3293                 oh->win_ctime[0] = in->win_ctime[0];
3294                 oh->win_mtime[0] = in->win_mtime[0];
3295                 oh->win_atime[1] = in->win_atime[1];
3296                 oh->win_ctime[1] = in->win_ctime[1];
3297                 oh->win_mtime[1] = in->win_mtime[1];
3298 #else
3299                 oh->yst_uid = in->yst_uid;
3300                 oh->yst_gid = in->yst_gid;
3301                 oh->yst_atime = in->yst_atime;
3302                 oh->yst_mtime = in->yst_mtime;
3303                 oh->yst_ctime = in->yst_ctime;
3304                 oh->yst_rdev = in->yst_rdev;
3305 #endif  
3306                 if(in->parent)
3307                 {
3308                         oh->parentObjectId = in->parent->objectId;
3309                 }
3310                 else
3311                 {
3312                         oh->parentObjectId = 0;
3313                 }
3314                 
3315                 //oh->sum = in->sum;
3316                 if(name && *name)
3317                 {
3318                         memset(oh->name,0,sizeof(oh->name));
3319                         yaffs_strncpy(oh->name,name,YAFFS_MAX_NAME_LENGTH);
3320                 }
3321                 else if(prevChunkId)
3322                 {       
3323                         memcpy(oh->name, oldName,sizeof(oh->name));
3324                 }
3325                 else
3326                 {
3327                         memset(oh->name,0,sizeof(oh->name));    
3328                 }
3329                 
3330                 oh->isShrink = isShrink;
3331         
3332                 switch(in->variantType)
3333                 {
3334                         case YAFFS_OBJECT_TYPE_UNKNOWN:         
3335                                 // Should not happen
3336                                 break;
3337                         case YAFFS_OBJECT_TYPE_FILE:
3338                                 oh->fileSize = (oh->parentObjectId == YAFFS_OBJECTID_DELETED ||
3339                                                 oh->parentObjectId == YAFFS_OBJECTID_UNLINKED) ? 0 : in->variant.fileVariant.fileSize;
3340                                 break;
3341                         case YAFFS_OBJECT_TYPE_HARDLINK:
3342                                 oh->equivalentObjectId = in->variant.hardLinkVariant.equivalentObjectId;
3343                                 break;
3344                         case YAFFS_OBJECT_TYPE_SPECIAL: 
3345                                 // Do nothing
3346                                 break;
3347                         case YAFFS_OBJECT_TYPE_DIRECTORY:       
3348                                 // Do nothing
3349                                 break;
3350                         case YAFFS_OBJECT_TYPE_SYMLINK:
3351                                 yaffs_strncpy(oh->alias,in->variant.symLinkVariant.alias,YAFFS_MAX_ALIAS_LENGTH);
3352                                 oh->alias[YAFFS_MAX_ALIAS_LENGTH] = 0;
3353                                 break;
3354                 }
3355
3356                 // Tags
3357                 yaffs_InitialiseTags(&newTags);
3358                 in->serial++;
3359                 newTags.chunkId = 0;
3360                 newTags.objectId = in->objectId;
3361                 newTags.serialNumber = in->serial;
3362                 
3363                 // Add extra info for file header
3364                 
3365                 newTags.extraHeaderInfoAvailable = 1;
3366                 newTags.extraParentObjectId = oh->parentObjectId;
3367                 newTags.extraFileLength = oh->fileSize;
3368                 newTags.extraIsShrinkHeader = oh->isShrink;
3369                 newTags.extraEquivalentObjectId = oh->equivalentObjectId;
3370                 newTags.extraObjectType  = in->variantType;
3371                 
3372                 // Create new chunk in NAND
3373                 newChunkId = yaffs_WriteNewChunkWithTagsToNAND(dev,buffer,&newTags, (prevChunkId >= 0) ? 1 : 0 );
3374     
3375                 if(newChunkId >= 0)
3376                 {
3377                 
3378                         in->chunkId = newChunkId;       
3379                 
3380                         if(prevChunkId >= 0)
3381                         {
3382                                 yaffs_DeleteChunk(dev,prevChunkId,1,__LINE__);
3383                         }
3384                 
3385                         in->dirty = 0;
3386                         
3387                         // If this was a shrink, then mark the block that the chunk lives on
3388                         if(isShrink)
3389                         {
3390                                 bi = yaffs_GetBlockInfo(in->myDev,newChunkId / in->myDev->nChunksPerBlock);
3391                                 bi->hasShrinkHeader = 1;
3392                         }
3393                         
3394                 }
3395                 
3396                 retVal =  newChunkId;
3397
3398     }
3399     
3400         if(buffer) 
3401                 yaffs_ReleaseTempBuffer(dev,buffer,__LINE__);
3402         
3403     return retVal;
3404 }
3405
3406
3407 /////////////////////// Short Operations Cache ////////////////////////////////
3408 //      In many siturations where there is no high level buffering (eg WinCE) a lot of
3409 //      reads might be short sequential reads, and a lot of writes may be short 
3410 //  sequential writes. eg. scanning/writing a jpeg file.
3411 //      In these cases, a short read/write cache can provide a huge perfomance benefit 
3412 //  with dumb-as-a-rock code.
3413 //  There are a limited number (~10) of cache chunks per device so that we don't
3414 //  need a very intelligent search.
3415
3416
3417
3418
3419
3420 static void yaffs_FlushFilesChunkCache(yaffs_Object *obj)
3421 {
3422         yaffs_Device *dev = obj->myDev;
3423         int lowest = -99; // Stop compiler whining.
3424         int i;
3425         yaffs_ChunkCache *cache;
3426         int chunkWritten = 0;
3427         //int nBytes;
3428         int nCaches = obj->myDev->nShortOpCaches;
3429         
3430         if  (nCaches > 0)
3431         {
3432                 do{
3433                         cache = NULL;
3434                 
3435                         // Find the dirty cache for this object with the lowest chunk id.
3436                         for(i = 0; i < nCaches; i++)
3437                         {
3438                                 if(dev->srCache[i].object == obj &&
3439                                    dev->srCache[i].dirty)
3440                                 {
3441                                         if(!cache ||  dev->srCache[i].chunkId < lowest)
3442                                         {
3443                                                 cache = &dev->srCache[i];
3444                                                 lowest = cache->chunkId;
3445                                         }
3446                                 }
3447                         }
3448                 
3449                         if(cache && !cache->locked)
3450                         {
3451                                 //Write it out and free it up
3452
3453 #if 0
3454                                 nBytes = cache->object->variant.fileVariant.fileSize - ((cache->chunkId -1) * YAFFS_BYTES_PER_CHUNK);
3455                         
3456                                 if(nBytes > YAFFS_BYTES_PER_CHUNK)
3457                                 {
3458                                         nBytes= YAFFS_BYTES_PER_CHUNK;
3459                                 }
3460 #endif                  
3461                                 chunkWritten = yaffs_WriteChunkDataToObject(cache->object,
3462                                                                                                                         cache->chunkId,
3463                                                                                                                         cache->data,
3464                                                                                                                         cache->nBytes,1);
3465
3466                                 cache->dirty = 0;
3467                                 cache->object = NULL;
3468                         }
3469                 
3470                 } while(cache && chunkWritten > 0);
3471         
3472                 if(cache)
3473                 {
3474                         //Hoosterman, disk full while writing cache out.
3475                         T(YAFFS_TRACE_ERROR, (TSTR("yaffs tragedy: no space during cache write" TENDSTR)));
3476
3477                 }
3478         }       
3479                 
3480 }
3481
3482
3483 // Grab us a chunk for use.
3484 // First look for an empty one. 
3485 // Then look for the least recently used non-dirty one.
3486 // Then look for the least recently used dirty one...., flush and look again.
3487 static yaffs_ChunkCache *yaffs_GrabChunkCacheWorker(yaffs_Device *dev)
3488 {
3489         int i;
3490         int usage;
3491         int theOne;
3492         
3493         if(dev->nShortOpCaches > 0)
3494         {
3495                 for(i = 0; i < dev->nShortOpCaches; i++)
3496                 {
3497                         if(!dev->srCache[i].object)
3498                         {
3499                                 //T(("Grabbing empty %d\n",i));
3500                                 
3501                                 //printf("Grabbing empty %d\n",i);
3502                         
3503                                 return &dev->srCache[i];
3504                         }
3505                 }
3506                 
3507                 return NULL;
3508         
3509                 theOne = -1; 
3510                 usage = 0; // just to stop the compiler grizzling
3511         
3512                 for(i = 0; i < dev->nShortOpCaches; i++)
3513                 {
3514                         if(!dev->srCache[i].dirty &&
3515                         ((dev->srCache[i].lastUse < usage  && theOne >= 0)|| 
3516                                 theOne < 0))
3517                         {
3518                                 usage = dev->srCache[i].lastUse;
3519                                 theOne = i;
3520                         }
3521                 }
3522         
3523                 //T(("Grabbing non-empty %d\n",theOne));
3524                 
3525                 //if(theOne >= 0) printf("Grabbed non-empty cache %d\n",theOne);
3526                 
3527                 return  theOne >= 0 ?  &dev->srCache[theOne] : NULL;
3528         }
3529         else
3530         {
3531                 return NULL;
3532         }
3533         
3534 }
3535
3536
3537 static yaffs_ChunkCache *yaffs_GrabChunkCache(yaffs_Device *dev)
3538 {
3539         yaffs_ChunkCache *cache;
3540         yaffs_Object *theObj;
3541         int usage;
3542         int i;
3543         int pushout;
3544         
3545         if(dev->nShortOpCaches > 0)
3546         {
3547                 // Try find a non-dirty one...
3548         
3549                 cache = yaffs_GrabChunkCacheWorker(dev);
3550         
3551                 if(!cache)
3552                 {
3553                         // They were all dirty, find the last recently used object and flush
3554                         // its cache, then  find again.
3555                         // NB what's here is not very accurate, we actually flush the object
3556                         // the last recently used page.
3557                         
3558                         // With locking we can't assume we can use entry zero
3559                         
3560                 
3561                         theObj = NULL;
3562                         usage = -1;
3563                         cache = NULL;
3564                         pushout = -1;
3565         
3566                         for(i = 0; i < dev->nShortOpCaches; i++)
3567                         {
3568                                 if( dev->srCache[i].object && 
3569                                         !dev->srCache[i].locked &&
3570                                         (dev->srCache[i].lastUse < usage || !cache))
3571                                 {
3572                                         usage  = dev->srCache[i].lastUse;
3573                                         theObj = dev->srCache[i].object;
3574                                         cache = &dev->srCache[i];
3575                                         pushout = i;
3576                                 }
3577                         }
3578                 
3579                         if(!cache || cache->dirty)
3580                         {
3581                         
3582                                 //printf("Dirty ");
3583                                 yaffs_FlushFilesChunkCache(theObj);
3584                 
3585                                 // Try again
3586                                 cache = yaffs_GrabChunkCacheWorker(dev);
3587                         }
3588                         else
3589                         {
3590                                 //printf(" pushout %d\n",pushout);
3591                         }
3592                         
3593                 }
3594                 return cache;
3595         }
3596         else
3597                 return NULL;
3598
3599 }
3600
3601
3602 // Find a cached chunk
3603 static yaffs_ChunkCache *yaffs_FindChunkCache(const yaffs_Object *obj, int chunkId)
3604 {
3605         yaffs_Device *dev = obj->myDev;
3606         int i;
3607         if(dev->nShortOpCaches > 0)
3608         {
3609                 for(i = 0; i < dev->nShortOpCaches; i++)
3610                 {
3611                         if(dev->srCache[i].object == obj && 
3612                         dev->srCache[i].chunkId == chunkId)
3613                         {
3614                                 dev->cacheHits++;
3615                         
3616                                 return &dev->srCache[i];
3617                         }
3618                 }
3619         }
3620         return NULL;
3621 }
3622
3623 // Mark the chunk for the least recently used algorithym
3624 static void yaffs_UseChunkCache(yaffs_Device *dev, yaffs_ChunkCache *cache, int isAWrite)
3625 {
3626
3627         if(dev->nShortOpCaches > 0)
3628         {
3629                 if( dev->srLastUse < 0 || 
3630                         dev->srLastUse > 100000000)
3631                 {
3632                         // Reset the cache usages
3633                         int i;
3634                         for(i = 1; i < dev->nShortOpCaches; i++)
3635                         {
3636                                 dev->srCache[i].lastUse = 0;
3637                         }
3638                         dev->srLastUse = 0;
3639                 }
3640
3641                 dev->srLastUse++;
3642         
3643                 cache->lastUse = dev->srLastUse;
3644
3645                 if(isAWrite)
3646                 {
3647                         cache->dirty = 1;
3648                 }
3649         }
3650 }
3651
3652 // Invalidate a single cache page.
3653 // Do this when a whole page gets written,
3654 // ie the short cache for this page is no longer valid.
3655 static void yaffs_InvalidateChunkCache(yaffs_Object *object, int chunkId)
3656 {
3657         if(object->myDev->nShortOpCaches > 0)
3658         {
3659                 yaffs_ChunkCache *cache = yaffs_FindChunkCache(object,chunkId);
3660
3661                 if(cache)
3662                 {
3663                         cache->object = NULL;
3664                 }
3665         }
3666 }
3667
3668
3669 // Invalidate all the cache pages associated with this object
3670 // Do this whenever ther file is deleted or resized.
3671 static void yaffs_InvalidateWholeChunkCache(yaffs_Object *in)
3672 {
3673         int i;
3674         yaffs_Device *dev = in->myDev;
3675         
3676         if(dev->nShortOpCaches > 0)
3677         { 
3678                 // Now invalidate it.
3679                 for(i = 0; i < dev->nShortOpCaches; i++)
3680                 {
3681                         if(dev->srCache[i].object == in)
3682                         {
3683                                 dev->srCache[i].object = NULL;
3684                         }
3685                 }
3686         }
3687 }
3688
3689
3690
3691
3692
3693 ///////////////////////// File read/write ///////////////////////////////
3694 // Read and write have very similar structures.
3695 // In general the read/write has three parts to it
3696 // * An incomplete chunk to start with (if the read/write is not chunk-aligned)
3697 // * Some complete chunks
3698 // * An incomplete chunk to end off with
3699 //
3700 // Curve-balls: the first chunk might also be the last chunk.
3701
3702 int yaffs_ReadDataFromFile(yaffs_Object *in, __u8 * buffer, __u32 offset, int nBytes)
3703 {
3704         
3705         
3706         int chunk;
3707         int start;
3708         int nToCopy;
3709         int n = nBytes;
3710         int nDone = 0;
3711         yaffs_ChunkCache *cache;
3712         
3713         yaffs_Device *dev;
3714         
3715         dev = in->myDev;
3716         
3717         while(n > 0)
3718         {
3719                 chunk = offset / dev->nBytesPerChunk + 1; // The first chunk is 1
3720                 start = offset % dev->nBytesPerChunk;
3721
3722                 // OK now check for the curveball where the start and end are in
3723                 // the same chunk.      
3724                 if(     (start + n) < dev->nBytesPerChunk)
3725                 {
3726                         nToCopy = n;
3727                 }
3728                 else
3729                 {
3730                         nToCopy = dev->nBytesPerChunk - start;
3731                 }
3732         
3733                 cache = yaffs_FindChunkCache(in,chunk);
3734                 
3735                 // If the chunk is already in the cache or it is less than a whole chunk
3736                 // then use the cache (if there is caching)
3737                 // else bypass the cache.
3738                 if( cache || nToCopy != dev->nBytesPerChunk)
3739                 {
3740                         if(dev->nShortOpCaches > 0)
3741                         {
3742                                 
3743                                 // If we can't find the data in the cache, then load it up.
3744                                 
3745                                 if(!cache)
3746                                 {
3747                                         cache = yaffs_GrabChunkCache(in->myDev);
3748                                         cache->object = in;
3749                                         cache->chunkId = chunk;
3750                                         cache->dirty = 0;
3751                                         cache->locked = 0;
3752                                         yaffs_ReadChunkDataFromObject(in,chunk,cache->data);
3753                                         cache->nBytes = 0;      
3754                                 }
3755                         
3756                                 yaffs_UseChunkCache(dev,cache,0);
3757
3758                                 cache->locked = 1;
3759
3760 #ifdef CONFIG_YAFFS_WINCE
3761                                 yfsd_UnlockYAFFS(TRUE);
3762 #endif
3763                                 memcpy(buffer,&cache->data[start],nToCopy);
3764
3765 #ifdef CONFIG_YAFFS_WINCE
3766                                 yfsd_LockYAFFS(TRUE);
3767 #endif
3768                                 cache->locked = 0;
3769                         }
3770                         else
3771                         {
3772                                 // Read into the local buffer then copy...
3773                                 
3774                                 __u8 *localBuffer = yaffs_GetTempBuffer(dev,__LINE__);
3775                                 yaffs_ReadChunkDataFromObject(in,chunk,localBuffer);            
3776 #ifdef CONFIG_YAFFS_WINCE
3777                                 yfsd_UnlockYAFFS(TRUE);
3778 #endif
3779                                 memcpy(buffer,&localBuffer[start],nToCopy);
3780
3781 #ifdef CONFIG_YAFFS_WINCE
3782                                 yfsd_LockYAFFS(TRUE);
3783 #endif
3784                                 yaffs_ReleaseTempBuffer(dev,localBuffer,__LINE__);
3785                         }
3786
3787                 }
3788                 else
3789                 {
3790 #ifdef CONFIG_YAFFS_WINCE
3791                         __u8 *localBuffer = yaffs_GetTempBuffer(dev,__LINE__);
3792                         
3793                         // Under WinCE can't do direct transfer. Need to use a local buffer.
3794                         // This is because we otherwise screw up WinCE's memory mapper
3795                         yaffs_ReadChunkDataFromObject(in,chunk,localBuffer);
3796
3797 #ifdef CONFIG_YAFFS_WINCE
3798                                 yfsd_UnlockYAFFS(TRUE);
3799 #endif
3800                         memcpy(buffer,localBuffer,dev->nBytesPerChunk);
3801
3802 #ifdef CONFIG_YAFFS_WINCE
3803                                 yfsd_LockYAFFS(TRUE);
3804                                 yaffs_ReleaseTempBuffer(dev,localBuffer,__LINE__);
3805 #endif
3806
3807 #else
3808                         // A full chunk. Read directly into the supplied buffer.
3809                         yaffs_ReadChunkDataFromObject(in,chunk,buffer);
3810 #endif
3811                 }
3812                 
3813                 n -= nToCopy;
3814                 offset += nToCopy;
3815                 buffer += nToCopy;
3816                 nDone += nToCopy;
3817                 
3818         }
3819         
3820         return nDone;
3821 }
3822
3823
3824
3825 int yaffs_WriteDataToFile(yaffs_Object *in,const __u8 * buffer, __u32 offset, int nBytes, int writeThrough)
3826 {       
3827         
3828         int chunk;
3829         int start;
3830         int nToCopy;
3831         int n = nBytes;
3832         int nDone = 0;
3833         int nToWriteBack;
3834         int startOfWrite = offset;
3835         int chunkWritten = 0;
3836         int nBytesRead;
3837         
3838         yaffs_Device *dev;
3839         
3840         dev = in->myDev;
3841         
3842         
3843         while(n > 0 && chunkWritten >= 0)
3844         {
3845                 chunk = offset / dev->nBytesPerChunk + 1;
3846                 start = offset % dev->nBytesPerChunk;
3847                 
3848
3849                 // OK now check for the curveball where the start and end are in
3850                 // the same chunk.
3851                 
3852                 if((start + n) < dev->nBytesPerChunk)
3853                 {
3854                         nToCopy = n;
3855                         
3856                         // Now folks, to calculate how many bytes to write back....
3857                         // If we're overwriting and not writing to then end of file then
3858                         // we need to write back as much as was there before.
3859                         
3860                         nBytesRead = in->variant.fileVariant.fileSize - ((chunk -1) * dev->nBytesPerChunk);
3861                         
3862                         if(nBytesRead > dev->nBytesPerChunk)
3863                         {
3864                                 nBytesRead = dev->nBytesPerChunk;
3865                         }
3866                         
3867                         nToWriteBack = (nBytesRead > (start + n)) ? nBytesRead : (start +n);
3868                         
3869                 }
3870                 else
3871                 {
3872                         nToCopy = dev->nBytesPerChunk - start;
3873                         nToWriteBack = dev->nBytesPerChunk;
3874                 }
3875         
3876                 if(nToCopy != dev->nBytesPerChunk)
3877                 {
3878                         // An incomplete start or end chunk (or maybe both start and end chunk)
3879                         if(dev->nShortOpCaches > 0)
3880                            {
3881                                 yaffs_ChunkCache *cache;
3882                                 // If we can't find the data in the cache, then load it up.
3883                                 cache = yaffs_FindChunkCache(in,chunk);
3884                                 if(!cache && yaffs_CheckSpaceForAllocation(in->myDev))
3885                                 {
3886                                         cache = yaffs_GrabChunkCache(in->myDev);
3887                                         cache->object = in;
3888                                         cache->chunkId = chunk;
3889                                         cache->dirty = 0;
3890                                         cache->locked = 0;
3891                                         yaffs_ReadChunkDataFromObject(in,chunk,cache->data);            
3892                                 }
3893                         
3894                                 if(cache)
3895                                 {       
3896                                         yaffs_UseChunkCache(dev,cache,1);
3897                                         cache->locked = 1;
3898 #ifdef CONFIG_YAFFS_WINCE
3899                                 yfsd_UnlockYAFFS(TRUE);
3900 #endif
3901         
3902                                         memcpy(&cache->data[start],buffer,nToCopy);
3903
3904 #ifdef CONFIG_YAFFS_WINCE
3905                                 yfsd_LockYAFFS(TRUE);
3906 #endif
3907                                         cache->locked = 0;
3908                                         cache->nBytes = nToWriteBack;
3909                                         
3910                                         if(writeThrough)
3911                                         {
3912                                                 chunkWritten = yaffs_WriteChunkDataToObject(cache->object,
3913                                                                                             cache->chunkId,
3914                                                                                             cache->data,
3915                                                                                             cache->nBytes,1);
3916                                                 cache->dirty = 0;
3917                                         }
3918
3919                                 }
3920                                 else
3921                                 {
3922                                         chunkWritten = -1; // fail the write
3923                                 }
3924                         }
3925                         else
3926                         {
3927                                 // An incomplete start or end chunk (or maybe both start and end chunk)
3928                                 // Read into the local buffer then copy, then copy over and write back.
3929                                 
3930                                 __u8 *localBuffer = yaffs_GetTempBuffer(dev,__LINE__);
3931                 
3932                                 yaffs_ReadChunkDataFromObject(in,chunk,localBuffer);
3933                                 
3934 #ifdef CONFIG_YAFFS_WINCE
3935                                 yfsd_UnlockYAFFS(TRUE);
3936 #endif
3937                                         
3938                                 memcpy(&localBuffer[start],buffer,nToCopy);
3939                         
3940 #ifdef CONFIG_YAFFS_WINCE
3941                                 yfsd_LockYAFFS(TRUE);
3942 #endif
3943                                 chunkWritten = yaffs_WriteChunkDataToObject(in,chunk,localBuffer,nToWriteBack,0);
3944                                 
3945                                 yaffs_ReleaseTempBuffer(dev,localBuffer,__LINE__);
3946                         
3947                                 //T(("Write with readback to chunk %d %d  start %d  copied %d wrote back %d\n",chunk,chunkWritten,start, nToCopy, nToWriteBack));
3948                         }
3949                         
3950                 }
3951                 else
3952                 {
3953                         
3954 #ifdef CONFIG_YAFFS_WINCE
3955                         // Under WinCE can't do direct transfer. Need to use a local buffer.
3956                         // This is because we otherwise screw up WinCE's memory mapper
3957                                 __u8 *localBuffer = yaffs_GetTempBuffer(dev,__LINE__);
3958 #ifdef CONFIG_YAFFS_WINCE
3959                                 yfsd_UnlockYAFFS(TRUE);
3960 #endif
3961                         memcpy(localBuffer,buffer,dev->nBytesPerChunk);
3962 #ifdef CONFIG_YAFFS_WINCE
3963                                 yfsd_LockYAFFS(TRUE);
3964 #endif
3965                         chunkWritten = yaffs_WriteChunkDataToObject(in,chunk,localBuffer,dev->nBytesPerChunk,0);
3966                         yaffs_ReleaseTempBuffer(dev,localBuffer,__LINE__);
3967 #else
3968                         // A full chunk. Write directly from the supplied buffer.
3969                         chunkWritten = yaffs_WriteChunkDataToObject(in,chunk,buffer,dev->nBytesPerChunk,0);
3970 #endif
3971                         // Since we've overwritten the cached data, we better invalidate it.
3972                         yaffs_InvalidateChunkCache(in,chunk);
3973                         //T(("Write to chunk %d %d\n",chunk,chunkWritten));
3974                 }
3975                 
3976                 if(chunkWritten >= 0)
3977                 {
3978                         n -= nToCopy;
3979                         offset += nToCopy;
3980                         buffer += nToCopy;
3981                         nDone += nToCopy;
3982                 }
3983                 
3984         }
3985         
3986         // Update file object
3987         
3988         if((startOfWrite + nDone) > in->variant.fileVariant.fileSize)
3989         {
3990                 in->variant.fileVariant.fileSize = (startOfWrite + nDone);
3991         }
3992         
3993         in->dirty = 1;
3994         
3995         return nDone;
3996 }
3997
3998 static void yaffs_PruneResizedChunks(yaffs_Object *in, int newSize)
3999 {
4000
4001         yaffs_Device *dev = in->myDev;
4002         int oldFileSize = in->variant.fileVariant.fileSize;
4003
4004         
4005         int lastDel = 1 + (oldFileSize-1)/dev->nBytesPerChunk;
4006                 
4007         int startDel = 1 + (newSize + dev->nBytesPerChunk - 1)/
4008                                                 dev->nBytesPerChunk;
4009         int i;
4010         int chunkId;
4011
4012         // Delete backwards so that we don't end up with holes if
4013         // power is lost part-way through the operation.
4014         for(i = lastDel; i >= startDel; i--)
4015         {
4016                 // NB this could be optimised somewhat,
4017                 // eg. could retrieve the tags and write them without
4018                 // using yaffs_DeleteChunk
4019
4020                 chunkId = yaffs_FindAndDeleteChunkInFile(in,i,NULL);
4021                 if(chunkId > 0)
4022                 {
4023                         if(chunkId < (dev->internalStartBlock * dev->nChunksPerBlock) || 
4024                        chunkId >= ((dev->internalEndBlock+1) * dev->nChunksPerBlock))
4025                         {
4026                                 T(YAFFS_TRACE_ALWAYS,(TSTR("Found daft chunkId %d for %d"TENDSTR),chunkId,i));
4027                         }
4028                         else
4029                         {
4030                                 in->nDataChunks--;
4031                                 yaffs_DeleteChunk(dev,chunkId,1,__LINE__);
4032                         }
4033                 }
4034         }
4035                 
4036 }
4037
4038 int yaffs_ResizeFile(yaffs_Object *in, int newSize)
4039 {
4040
4041         int oldFileSize = in->variant.fileVariant.fileSize;
4042         int sizeOfPartialChunk;
4043         yaffs_Device *dev = in->myDev;
4044         
4045          sizeOfPartialChunk  = newSize % dev->nBytesPerChunk;
4046                 
4047
4048         yaffs_FlushFilesChunkCache(in); 
4049         yaffs_InvalidateWholeChunkCache(in);
4050
4051         yaffs_CheckGarbageCollection(dev);
4052         
4053         if(in->variantType != YAFFS_OBJECT_TYPE_FILE)
4054         {
4055                 return yaffs_GetFileSize(in);
4056         }
4057         
4058         if(newSize < oldFileSize)
4059         {
4060
4061                 yaffs_PruneResizedChunks(in,newSize);
4062                 
4063                 if(sizeOfPartialChunk != 0)
4064                 {
4065                         int lastChunk = 1+ newSize/dev->nBytesPerChunk;
4066                         __u8 *localBuffer = yaffs_GetTempBuffer(dev,__LINE__);
4067                         
4068                         // Got to read and rewrite the last chunk with its new size and zero pad
4069                         yaffs_ReadChunkDataFromObject(in,lastChunk,localBuffer);
4070                         
4071                         memset(localBuffer + sizeOfPartialChunk,0, dev->nBytesPerChunk - sizeOfPartialChunk);
4072                         
4073                         yaffs_WriteChunkDataToObject(in,lastChunk,localBuffer,sizeOfPartialChunk,1);
4074                                 
4075                         yaffs_ReleaseTempBuffer(dev,localBuffer,__LINE__);
4076                 }
4077                 
4078                 in->variant.fileVariant.fileSize = newSize;
4079                 
4080                 yaffs_PruneFileStructure(dev,&in->variant.fileVariant);
4081                 
4082                 // Write a new object header to show we've shrunk the file
4083                 // Do this only if the file is not in the deleted directories.
4084                 if(in->parent->objectId != YAFFS_OBJECTID_UNLINKED &&
4085                    in->parent->objectId != YAFFS_OBJECTID_DELETED
4086                   )
4087                 {
4088                         yaffs_UpdateObjectHeader(in,NULL, 0, 1);
4089                 }
4090
4091                 
4092                 return newSize;
4093                 
4094         }
4095         else
4096         {
4097                 return oldFileSize;
4098         }
4099 }
4100
4101
4102 loff_t yaffs_GetFileSize(yaffs_Object *obj)
4103 {
4104         obj = yaffs_GetEquivalentObject(obj);
4105         
4106         switch(obj->variantType)
4107         {
4108                 case YAFFS_OBJECT_TYPE_FILE: 
4109                         return obj->variant.fileVariant.fileSize;
4110                 case YAFFS_OBJECT_TYPE_SYMLINK:
4111                         return yaffs_strlen(obj->variant.symLinkVariant.alias);
4112                 default:
4113                         return 0;
4114         }
4115 }
4116
4117
4118
4119 // yaffs_FlushFile() updates the file's
4120 // objectId in NAND
4121
4122 int yaffs_FlushFile(yaffs_Object *in, int updateTime)
4123 {
4124         int retVal;
4125         if(in->dirty)
4126         {
4127                 //T(("flushing object header\n"));
4128                 
4129                 yaffs_FlushFilesChunkCache(in);
4130                 if(updateTime)
4131                 {
4132 #ifdef CONFIG_YAFFS_WINCE
4133                         yfsd_WinFileTimeNow(in->win_mtime);
4134 #else
4135
4136                         in->yst_mtime = Y_CURRENT_TIME;
4137
4138 #endif
4139                 }
4140
4141                 retVal = (yaffs_UpdateObjectHeader(in,NULL,0,0) >= 0)? YAFFS_OK : YAFFS_FAIL;
4142         }
4143         else
4144         {
4145                 retVal = YAFFS_OK;
4146         }
4147         
4148         return retVal;
4149         
4150 }
4151
4152
4153 static int yaffs_DoGenericObjectDeletion(yaffs_Object *in)
4154 {
4155
4156         // First off, invalidate the file's data in the cache, without flushing.
4157         yaffs_InvalidateWholeChunkCache(in);
4158
4159         if(in->myDev->isYaffs2 && (in->parent != in->myDev->deletedDir))
4160         {
4161                 // Move to the unlinked directory so we have a record that it was deleted.
4162                 yaffs_ChangeObjectName(in, in->myDev->deletedDir,NULL,0);
4163
4164         }
4165
4166         
4167         yaffs_RemoveObjectFromDirectory(in);
4168         yaffs_DeleteChunk(in->myDev,in->chunkId,1,__LINE__);
4169         in->chunkId = -1;
4170 #if 0
4171 #ifdef __KERNEL__
4172         if(in->myInode)
4173         {
4174                 in->myInode->u.generic_ip = NULL;
4175                 in->myInode = 0;
4176         }
4177 #endif
4178 #endif
4179
4180         yaffs_FreeObject(in);
4181         return YAFFS_OK;
4182
4183 }
4184
4185 // yaffs_DeleteFile deletes the whole file data
4186 // and the inode associated with the file.
4187 // It does not delete the links associated with the file.
4188 static int yaffs_UnlinkFile(yaffs_Object *in)
4189 {
4190
4191 #ifdef CONFIG_YAFFS_DISABLE_BACKGROUND_DELETION
4192
4193         // Delete the file data & tnodes
4194
4195          yaffs_DeleteWorker(in, in->variant.fileVariant.top, in->variant.fileVariant.topLevel, 0,NULL);
4196          
4197
4198         yaffs_FreeTnode(in->myDev,in->variant.fileVariant.top);
4199         
4200         return  yaffs_DoGenericObjectDeletion(in);
4201 #else
4202         int retVal;
4203         int immediateDeletion=0;
4204
4205         if(1)
4206         {
4207                 //in->unlinked = 1;
4208                 //in->myDev->nUnlinkedFiles++;
4209                 //in->renameAllowed = 0;
4210 #ifdef __KERNEL__
4211                 if(!in->myInode)
4212                 {
4213                         immediateDeletion = 1;
4214
4215                 }
4216 #else
4217                 if(in->inUse <= 0)
4218                 {
4219                         immediateDeletion = 1;
4220
4221                 }
4222 #endif
4223                 if(immediateDeletion)
4224                 {
4225                         retVal = yaffs_ChangeObjectName(in, in->myDev->deletedDir,NULL,0);
4226                         T(YAFFS_TRACE_TRACING,(TSTR("yaffs: immediate deletion of file %d" TENDSTR),in->objectId));
4227                         in->deleted=1;
4228                         in->myDev->nDeletedFiles++;
4229                         if( 0 && in->myDev->isYaffs2)
4230                         {
4231                                 yaffs_ResizeFile(in,0);
4232                         }
4233                         yaffs_SoftDeleteFile(in);
4234                 }
4235                 else
4236                 {
4237                         retVal = yaffs_ChangeObjectName(in, in->myDev->unlinkedDir,NULL,0);
4238                 }
4239         
4240         }
4241         return retVal;
4242
4243         
4244 #endif
4245 }
4246
4247 int yaffs_DeleteFile(yaffs_Object *in)
4248 {
4249         int retVal = YAFFS_OK;
4250         
4251         if(in->nDataChunks > 0)
4252         {
4253                 // Use soft deletion
4254                 if(!in->unlinked)
4255                 {
4256                         retVal = yaffs_UnlinkFile(in);
4257                 }
4258                 if(retVal == YAFFS_OK && 
4259                 in->unlinked &&
4260                 !in->deleted)
4261                 {
4262                         in->deleted = 1;
4263                         in->myDev->nDeletedFiles++;
4264                         yaffs_SoftDeleteFile(in);
4265                 }
4266                 return in->deleted ? YAFFS_OK : YAFFS_FAIL;     
4267         }
4268         else
4269         {
4270                 // The file has no data chunks so we toss it immediately
4271                 yaffs_FreeTnode(in->myDev,in->variant.fileVariant.top);
4272                 in->variant.fileVariant.top = NULL;
4273                 yaffs_DoGenericObjectDeletion(in);      
4274                 
4275                 return YAFFS_OK;        
4276         }
4277 }
4278
4279 static int yaffs_DeleteDirectory(yaffs_Object *in)
4280 {
4281         //First check that the directory is empty.
4282         if(list_empty(&in->variant.directoryVariant.children))
4283         {
4284                 return  yaffs_DoGenericObjectDeletion(in);
4285         }
4286         
4287         return YAFFS_FAIL;
4288         
4289 }
4290
4291 static int yaffs_DeleteSymLink(yaffs_Object *in)
4292 {
4293         YFREE(in->variant.symLinkVariant.alias);
4294
4295         return  yaffs_DoGenericObjectDeletion(in);
4296 }
4297
4298 static int yaffs_DeleteHardLink(yaffs_Object *in)
4299 {
4300         // remove this hardlink from the list assocaited with the equivalent
4301         // object
4302         list_del(&in->hardLinks);
4303         return  yaffs_DoGenericObjectDeletion(in);      
4304 }
4305
4306
4307 static void yaffs_DestroyObject(yaffs_Object *obj)
4308 {
4309         switch(obj->variantType)
4310         {
4311                 case YAFFS_OBJECT_TYPE_FILE: yaffs_DeleteFile(obj); break;
4312                 case YAFFS_OBJECT_TYPE_DIRECTORY: yaffs_DeleteDirectory(obj); break;
4313                 case YAFFS_OBJECT_TYPE_SYMLINK: yaffs_DeleteSymLink(obj); break;
4314                 case YAFFS_OBJECT_TYPE_HARDLINK: yaffs_DeleteHardLink(obj); break;
4315                 case YAFFS_OBJECT_TYPE_SPECIAL: yaffs_DoGenericObjectDeletion(obj); break;
4316                 case YAFFS_OBJECT_TYPE_UNKNOWN: break; // should not happen.
4317         }
4318 }
4319
4320
4321 static int yaffs_UnlinkWorker(yaffs_Object *obj)
4322 {
4323
4324         
4325         if(obj->variantType == YAFFS_OBJECT_TYPE_HARDLINK)
4326         {
4327                 return  yaffs_DeleteHardLink(obj);
4328         }
4329         else if(!list_empty(&obj->hardLinks))
4330         {       
4331                 // Curve ball: We're unlinking an object that has a hardlink.
4332                 //
4333                 //      This problem arises because we are not strictly following
4334                 //  The Linux link/inode model.
4335                 //
4336                 // We can't really delete the object.
4337                 // Instead, we do the following:
4338                 // - Select a hardlink.
4339                 // - Unhook it from the hard links
4340                 // - Unhook it from its parent directory (so that the rename can work)
4341                 // - Rename the object to the hardlink's name.
4342                 // - Delete the hardlink
4343                 
4344                 
4345                 yaffs_Object *hl;
4346                 int retVal;
4347                 YCHAR name[YAFFS_MAX_NAME_LENGTH+1];
4348                 
4349                 hl = list_entry(obj->hardLinks.next,yaffs_Object,hardLinks);
4350                 
4351                 list_del_init(&hl->hardLinks);
4352                 list_del_init(&hl->siblings);
4353                 
4354                 yaffs_GetObjectName(hl,name,YAFFS_MAX_NAME_LENGTH+1);
4355                 
4356                 retVal = yaffs_ChangeObjectName(obj, hl->parent, name,0);
4357                 
4358                 if(retVal == YAFFS_OK)
4359                 {
4360                         retVal = yaffs_DoGenericObjectDeletion(hl);
4361                 }
4362                 return retVal;
4363                                 
4364         }
4365         else
4366         {
4367                 switch(obj->variantType)
4368                 {
4369                         case YAFFS_OBJECT_TYPE_FILE:
4370                                 return yaffs_UnlinkFile(obj);
4371                                 break;
4372                         case YAFFS_OBJECT_TYPE_DIRECTORY:
4373                                 return yaffs_DeleteDirectory(obj);
4374                                 break;
4375                         case YAFFS_OBJECT_TYPE_SYMLINK:
4376                                 return yaffs_DeleteSymLink(obj);
4377                                 break;
4378                         case YAFFS_OBJECT_TYPE_SPECIAL:
4379                                 return yaffs_DoGenericObjectDeletion(obj);
4380                                 break;
4381                         case YAFFS_OBJECT_TYPE_HARDLINK:
4382                         case YAFFS_OBJECT_TYPE_UNKNOWN:
4383                         default:
4384                                 return YAFFS_FAIL;
4385                 }
4386         }
4387 }
4388
4389 int yaffs_Unlink(yaffs_Object *dir, const YCHAR *name)
4390 {
4391         yaffs_Object *obj;
4392         
4393          obj = yaffs_FindObjectByName(dir,name);
4394          
4395          if(obj && obj->unlinkAllowed)
4396          {
4397                 return yaffs_UnlinkWorker(obj);
4398          }
4399          
4400          return YAFFS_FAIL;
4401         
4402 }
4403
4404 //////////////// Initialisation Scanning /////////////////
4405
4406
4407 #if 0
4408 // For now we use the SmartMedia check.
4409 // We look at the blockStatus byte in the first two chunks
4410 // These must be 0xFF to pass as OK.
4411 // todo: this function needs to be modifyable foir different NAND types
4412 // and different chunk sizes.  Suggest make this into a per-device configurable
4413 // function.
4414 static int yaffs_IsBlockBad(yaffs_Device *dev, int blk)
4415 {
4416         yaffsExtendedTags *tags;
4417         
4418         yaffs_ReadChunkFromNAND(dev,blk * dev->nChunksPerBlock,NULL,&tags,1);
4419 #if 1
4420         if(yaffs_CountBits(spare.blockStatus) < 7)
4421         {
4422                 return 1;
4423         }
4424 #else
4425         if(spare.blockStatus != 0xFF)
4426         {
4427                 return 1;
4428         }
4429 #endif
4430         yaffs_ReadChunkFromNAND(dev,blk * dev->nChunksPerBlock + 1,NULL,&spare,1);
4431
4432 #if 1
4433         if(yaffs_CountBits(spare.blockStatus) < 7)
4434         {
4435                 return 1;
4436         }
4437 #else
4438         if(spare.blockStatus != 0xFF)
4439         {
4440                 return 1;
4441         }
4442 #endif
4443         
4444         return 0;
4445         
4446 }
4447
4448 #endif
4449
4450
4451 typedef struct 
4452 {
4453         int seq;
4454         int block;
4455 } yaffs_BlockIndex;
4456
4457
4458
4459 static int yaffs_Scan(yaffs_Device *dev)
4460 {
4461         yaffs_ExtendedTags tags;
4462         int blk;
4463         int blockIterator;
4464         int startIterator;
4465         int endIterator;
4466         int nBlocksToScan = 0;
4467         
4468         int chunk;
4469         int c;
4470         int deleted;
4471         yaffs_BlockState state;
4472         yaffs_Object *hardList = NULL;
4473         yaffs_Object *hl;
4474         yaffs_BlockInfo *bi;
4475         int sequenceNumber;     
4476         yaffs_ObjectHeader *oh;
4477         yaffs_Object *in;
4478         yaffs_Object *parent;
4479         int nBlocks = dev->internalEndBlock - dev->internalStartBlock + 1;
4480         
4481         __u8 *chunkData;
4482
4483         yaffs_BlockIndex *blockIndex = NULL;
4484
4485         T(YAFFS_TRACE_SCAN,(TSTR("yaffs_Scan starts  intstartblk %d intendblk %d..." TENDSTR),dev->internalStartBlock,dev->internalEndBlock));
4486         
4487         chunkData = yaffs_GetTempBuffer(dev,__LINE__);
4488         
4489         
4490         dev->sequenceNumber = YAFFS_LOWEST_SEQUENCE_NUMBER;
4491         
4492         if(dev->isYaffs2)
4493         {
4494                 blockIndex = YMALLOC(nBlocks * sizeof(yaffs_BlockIndex));               
4495         }
4496         
4497         
4498         // Scan all the blocks to determine their state
4499         for(blk = dev->internalStartBlock; blk <= dev->internalEndBlock; blk++)
4500         {
4501                 bi = yaffs_GetBlockInfo(dev,blk);
4502                 yaffs_ClearChunkBits(dev,blk);
4503                 bi->pagesInUse = 0;
4504                 bi->softDeletions = 0;
4505                                 
4506                 yaffs_QueryInitialBlockState(dev,blk,&state,&sequenceNumber);
4507                 
4508                 bi->blockState = state;
4509                 bi->sequenceNumber = sequenceNumber;
4510
4511                 T(YAFFS_TRACE_SCAN_DEBUG,(TSTR("Block scanning block %d state %d seq %d" TENDSTR),blk,state,sequenceNumber));
4512                 
4513                 if(state == YAFFS_BLOCK_STATE_DEAD)
4514                 {
4515                         T(YAFFS_TRACE_BAD_BLOCKS,(TSTR("block %d is bad" TENDSTR),blk));
4516                 }
4517                 else if(state == YAFFS_BLOCK_STATE_EMPTY)
4518                 {
4519                         T(YAFFS_TRACE_SCAN_DEBUG,(TSTR("Block empty " TENDSTR)));
4520                         dev->nErasedBlocks++;
4521                         dev->nFreeChunks += dev->nChunksPerBlock;
4522                 }
4523                 else if(state == YAFFS_BLOCK_STATE_NEEDS_SCANNING)
4524                 {
4525                                         
4526                         // Determine the highest sequence number
4527                         if( dev->isYaffs2 &&
4528                             sequenceNumber >= YAFFS_LOWEST_SEQUENCE_NUMBER &&
4529                             sequenceNumber < YAFFS_HIGHEST_SEQUENCE_NUMBER)
4530                          {
4531                                 
4532                                 blockIndex[nBlocksToScan].seq = sequenceNumber;
4533                                 blockIndex[nBlocksToScan].block = blk;
4534                                 
4535                                 nBlocksToScan++;
4536
4537                                 if(sequenceNumber >= dev->sequenceNumber)
4538                                 {
4539                                         dev->sequenceNumber = sequenceNumber;
4540                                 }
4541                         }
4542                         else if(dev->isYaffs2)
4543                         {
4544                                 // TODO: Nasty sequence number!
4545                                 T(YAFFS_TRACE_SCAN,(TSTR("Block scanning block %d has bad sequence number %d" TENDSTR),blk,sequenceNumber));
4546
4547                         }
4548                 }
4549         }
4550         
4551         // Sort the blocks
4552         // Dungy old bubble sort for now...
4553         if(dev->isYaffs2)
4554         {
4555                 yaffs_BlockIndex temp;
4556                 int i;
4557                 int j;
4558                 
4559                 for(i = 0; i < nBlocksToScan; i++)
4560                         for(j = i+1; j < nBlocksToScan; j++)
4561                          if(blockIndex[i].seq > blockIndex[j].seq)
4562                          {
4563                                 temp = blockIndex[j];
4564                                 blockIndex[j] = blockIndex[i];
4565                                 blockIndex[i] = temp;
4566                          }
4567         }
4568         
4569         
4570         // Now scan the blocks looking at the data.
4571         if(dev->isYaffs2)
4572         {
4573                 startIterator = 0;
4574                 endIterator = nBlocksToScan-1;
4575                 T(YAFFS_TRACE_SCAN_DEBUG,(TSTR("%d blocks to be scanned" TENDSTR),nBlocksToScan));
4576         }
4577         else
4578         {
4579                 startIterator = dev->internalStartBlock;
4580                 endIterator = dev->internalEndBlock;
4581         }
4582         
4583         // For each block....
4584         for(blockIterator = startIterator; blockIterator <= endIterator; blockIterator++)
4585         {
4586         
4587                 if(dev->isYaffs2)
4588                 {
4589                         // get the block to scan in the correct order
4590                         blk = blockIndex[blockIterator].block;
4591                 }
4592                 else
4593                 {
4594                         blk = blockIterator;
4595                 }
4596
4597
4598                 bi = yaffs_GetBlockInfo(dev,blk);
4599                 state = bi->blockState;
4600                 
4601                 deleted = 0;
4602                 
4603                 // For each chunk in each block that needs scanning....
4604                 for(c = 0; c < dev->nChunksPerBlock && 
4605                                    state == YAFFS_BLOCK_STATE_NEEDS_SCANNING; c++)
4606                 {
4607                         // Read the tags and decide what to do
4608                         chunk = blk * dev->nChunksPerBlock + c;
4609                         
4610                         yaffs_ReadChunkWithTagsFromNAND(dev,chunk,NULL,&tags);
4611
4612                         // Let's have a good look at this chunk...
4613         
4614                         
4615                         if(!dev->isYaffs2 && tags.chunkDeleted)
4616                         {
4617                                 // YAFFS1 only...
4618                                 // A deleted chunk
4619                                 deleted++;
4620                                 dev->nFreeChunks ++;
4621                                 //T((" %d %d deleted\n",blk,c));
4622                         }
4623                         else if(!tags.chunkUsed)
4624                         {
4625                                 // An unassigned chunk in the block
4626                                 // This means that either the block is empty or 
4627                                 // this is the one being allocated from
4628                                 
4629                                 if(c == 0)
4630                                 {
4631                                         // We're looking at the first chunk in the block so the block is unused
4632                                         state = YAFFS_BLOCK_STATE_EMPTY;
4633                                         dev->nErasedBlocks++;
4634                                 }
4635                                 else
4636                                 {
4637                                         // this is the block being allocated from
4638                                         T(YAFFS_TRACE_SCAN,(TSTR(" Allocating from %d %d" TENDSTR),blk,c));
4639                                         state = YAFFS_BLOCK_STATE_ALLOCATING;
4640                                         dev->allocationBlock = blk;
4641                                         dev->allocationPage = c;
4642                                         dev->allocationBlockFinder = blk; // Set it to here to encourage the allocator to
4643                                                                                                           // go forth from here.
4644                                         //Yaffs2 sanity check:
4645                                         // This should be the one with the highest sequence number
4646                                         if(dev->isYaffs2 && (dev->sequenceNumber != bi->sequenceNumber))
4647                                         {
4648                                                 T(YAFFS_TRACE_ALWAYS,
4649                                                                 (TSTR("yaffs: Allocation block %d was not highest sequence id: block seq = %d, dev seq = %d" TENDSTR),
4650                                                                 blk,bi->sequenceNumber,dev->sequenceNumber));
4651                                         }
4652                                 }
4653
4654                                 dev->nFreeChunks += (dev->nChunksPerBlock - c);
4655                         }
4656                         else if(tags.chunkId > 0)
4657                         {
4658                                 // chunkId > 0 so it is a data chunk...
4659                                 unsigned int endpos;
4660
4661                                 yaffs_SetChunkBit(dev,blk,c);
4662                                 bi->pagesInUse++;
4663                                                                 
4664                                 in = yaffs_FindOrCreateObjectByNumber(dev,tags.objectId,YAFFS_OBJECT_TYPE_FILE);
4665                                 // PutChunkIntoFile checks for a clash (two data chunks with
4666                                 // the same chunkId).
4667                                 yaffs_PutChunkIntoFile(in,tags.chunkId,chunk,1);
4668                                 endpos = (tags.chunkId - 1)* dev->nBytesPerChunk + tags.byteCount;
4669                                 if(in->variantType == YAFFS_OBJECT_TYPE_FILE && in->variant.fileVariant.scannedFileSize <endpos)
4670                                 {
4671                                         in->variant.fileVariant.scannedFileSize = endpos;
4672                                         if(!dev->useHeaderFileSize)
4673                                         {       
4674                                                         in->variant.fileVariant.fileSize = in->variant.fileVariant.scannedFileSize;
4675                                         }
4676
4677                                 }
4678                                 //T((" %d %d data %d %d\n",blk,c,tags.objectId,tags.chunkId));  
4679                         }
4680                         else
4681                         {
4682                                 // chunkId == 0, so it is an ObjectHeader.
4683                                 // Thus, we read in the object header and make the object
4684                                 yaffs_SetChunkBit(dev,blk,c);
4685                                 bi->pagesInUse++;
4686                                                         
4687                                 yaffs_ReadChunkWithTagsFromNAND(dev,chunk,chunkData,NULL);
4688                                 
4689                                 oh = (yaffs_ObjectHeader *)chunkData;
4690                                 
4691                                 in = yaffs_FindObjectByNumber(dev,tags.objectId);
4692                                 if(in && in->variantType != oh->type)
4693                                 {
4694                                         // This should not happen, but somehow
4695                                         // Wev'e ended up with an objectId that has been reused but not yet 
4696                                         // deleted, and worse still it has changed type. Delete the old object.
4697                                         
4698                                         yaffs_DestroyObject(in);
4699                                         
4700                                         in = 0;
4701                                 }
4702                                 
4703                                 in = yaffs_FindOrCreateObjectByNumber(dev,tags.objectId,oh->type);
4704                                 
4705                                 if(in->valid)
4706                                 {
4707                                         // We have already filled this one. We have a duplicate and need to resolve it.
4708                                         
4709                                         unsigned existingSerial = in->serial;
4710                                         unsigned newSerial = tags.serialNumber;
4711                                         
4712                                         if( dev->isYaffs2 ||
4713                                             ((existingSerial+1) & 3) == newSerial)
4714                                         {
4715                                                 // Use new one - destroy the exisiting one
4716                                                 yaffs_DeleteChunk(dev,in->chunkId,1,__LINE__);
4717                                                 in->valid = 0;
4718                                         }
4719                                         else
4720                                         {
4721                                                 // Use existing - destroy this one.
4722                                                 yaffs_DeleteChunk(dev,chunk,1,__LINE__);
4723                                         }
4724                                 }
4725                                 
4726                                 if(!in->valid &&
4727                                    (tags.objectId == YAFFS_OBJECTID_ROOT ||
4728                                     tags.objectId == YAFFS_OBJECTID_LOSTNFOUND))
4729                                 {
4730                                         // We only load some info, don't fiddle with directory structure
4731                                         in->valid = 1;
4732                                         in->variantType = oh->type;
4733         
4734                                         in->yst_mode  = oh->yst_mode;
4735 #ifdef CONFIG_YAFFS_WINCE
4736                                         in->win_atime[0] = oh->win_atime[0];
4737                                         in->win_ctime[0] = oh->win_ctime[0];
4738                                         in->win_mtime[0] = oh->win_mtime[0];
4739                                         in->win_atime[1] = oh->win_atime[1];
4740                                         in->win_ctime[1] = oh->win_ctime[1];
4741                                         in->win_mtime[1] = oh->win_mtime[1];
4742 #else
4743                                         in->yst_uid   = oh->yst_uid;
4744                                         in->yst_gid   = oh->yst_gid;
4745                                         in->yst_atime = oh->yst_atime;
4746                                         in->yst_mtime = oh->yst_mtime;
4747                                         in->yst_ctime = oh->yst_ctime;
4748                                         in->yst_rdev = oh->yst_rdev;
4749 #endif
4750                                         in->chunkId  = chunk;
4751
4752                                 }
4753                                 else if(!in->valid)
4754                                 {
4755                                         // we need to load this info
4756                                 
4757                                         in->valid = 1;
4758                                         in->variantType = oh->type;
4759         
4760                                         in->yst_mode  = oh->yst_mode;
4761 #ifdef CONFIG_YAFFS_WINCE
4762                                         in->win_atime[0] = oh->win_atime[0];
4763                                         in->win_ctime[0] = oh->win_ctime[0];
4764                                         in->win_mtime[0] = oh->win_mtime[0];
4765                                         in->win_atime[1] = oh->win_atime[1];
4766                                         in->win_ctime[1] = oh->win_ctime[1];
4767                                         in->win_mtime[1] = oh->win_mtime[1];
4768 #else
4769                                         in->yst_uid   = oh->yst_uid;
4770                                         in->yst_gid   = oh->yst_gid;
4771                                         in->yst_atime = oh->yst_atime;
4772                                         in->yst_mtime = oh->yst_mtime;
4773                                         in->yst_ctime = oh->yst_ctime;
4774                                         in->yst_rdev = oh->yst_rdev;
4775 #endif
4776                                         in->chunkId  = chunk;
4777
4778                                         yaffs_SetObjectName(in,oh->name);
4779                                         in->dirty = 0;
4780                                                         
4781                                         // directory stuff...
4782                                         // hook up to parent
4783         
4784                                         parent = yaffs_FindOrCreateObjectByNumber(dev,oh->parentObjectId,YAFFS_OBJECT_TYPE_DIRECTORY);
4785                                         if(parent->variantType == YAFFS_OBJECT_TYPE_UNKNOWN)
4786                                         {
4787                                                 // Set up as a directory
4788                                                 parent->variantType = YAFFS_OBJECT_TYPE_DIRECTORY;
4789                                                 INIT_LIST_HEAD(&parent->variant.directoryVariant.children);
4790                                         }
4791                                         else if(parent->variantType != YAFFS_OBJECT_TYPE_DIRECTORY)
4792                                         {
4793                                                 // Hoosterman, another problem....
4794                                                 // We're trying to use a non-directory as a directory
4795
4796                                                 T(YAFFS_TRACE_ERROR, (TSTR("yaffs tragedy: attempting to use non-directory as a directory in scan. Put in lost+found." TENDSTR)));
4797                                                 parent = dev->lostNFoundDir;
4798                                         }
4799                                 
4800                                         yaffs_AddObjectToDirectory(parent,in);
4801
4802                                         if(0 && (parent == dev->deletedDir ||
4803                                            parent == dev->unlinkedDir))
4804                                         {
4805                                                 in->deleted = 1; // If it is unlinked at start up then it wants deleting
4806                                                 dev->nDeletedFiles++;
4807                                         }
4808                                 
4809                                         // Note re hardlinks.
4810                                         // Since we might scan a hardlink before its equivalent object is scanned
4811                                         // we put them all in a list.
4812                                         // After scanning is complete, we should have all the objects, so we run through this
4813                                         // list and fix up all the chains.              
4814         
4815                                         switch(in->variantType)
4816                                         {
4817                                                 case YAFFS_OBJECT_TYPE_UNKNOWN:         // Todo got a problem
4818                                                         break;
4819                                                 case YAFFS_OBJECT_TYPE_FILE:
4820                                                         if(dev->isYaffs2 && oh->isShrink)
4821                                                         {
4822                                                                 // Prune back the shrunken chunks
4823                                                                 yaffs_PruneResizedChunks(in,oh->fileSize);
4824                                                                 // Mark the block as having a shrinkHeader
4825                                                                 bi->hasShrinkHeader = 1;
4826                                                         }
4827                                                         
4828                                                         if(dev->useHeaderFileSize)
4829                                                 
4830                                                                 in->variant.fileVariant.fileSize = oh->fileSize;
4831                                                                 
4832                                                         break;
4833                                                 case YAFFS_OBJECT_TYPE_HARDLINK:
4834                                                         in->variant.hardLinkVariant.equivalentObjectId = oh->equivalentObjectId;
4835                                                         in->hardLinks.next = (struct list_head *)hardList;
4836                                                         hardList = in;
4837                                                         break;
4838                                                 case YAFFS_OBJECT_TYPE_DIRECTORY:       // Do nothing
4839                                                         break;
4840                                                 case YAFFS_OBJECT_TYPE_SPECIAL: // Do nothing
4841                                                         break;
4842                                                 case YAFFS_OBJECT_TYPE_SYMLINK:         // Do nothing
4843                                                         in->variant.symLinkVariant.alias = yaffs_CloneString(oh->alias);
4844                                                         break;
4845                                         }
4846
4847                                         if(parent == dev->deletedDir)
4848                                         {
4849                                                 yaffs_DestroyObject(in);
4850                                                 bi->hasShrinkHeader = 1;
4851                                         }
4852                                         //T((" %d %d header %d \"%s\" type %d\n",blk,c,tags.objectId,oh->name,in->variantType));        
4853                                 }
4854                         }
4855                 }
4856                 
4857                 if(state == YAFFS_BLOCK_STATE_NEEDS_SCANNING)
4858                 {
4859                         // If we got this far while scanning, then the block is fully allocated.
4860                         state = YAFFS_BLOCK_STATE_FULL; 
4861                 }
4862                 
4863                 bi->blockState = state;
4864                 
4865                 // Now let's see if it was dirty
4866                 if(     bi->pagesInUse == 0 &&
4867                         !bi->hasShrinkHeader &&
4868                 bi->blockState == YAFFS_BLOCK_STATE_FULL)
4869             {
4870                 yaffs_BlockBecameDirty(dev,blk);
4871             }
4872
4873         }
4874         
4875         if(blockIndex)
4876         {
4877                 YFREE(blockIndex);
4878         }
4879         
4880         // Ok, we've done all the scanning.
4881         
4882         // Fix up the hard link chains.
4883         // We should now have scanned all the objects, now it's time to add these 
4884         // hardlinks.
4885         while(hardList)
4886         {
4887                 hl = hardList;
4888                 hardList = (yaffs_Object *)(hardList->hardLinks.next);
4889                 
4890                 in = yaffs_FindObjectByNumber(dev,hl->variant.hardLinkVariant.equivalentObjectId);
4891                 
4892                 if(in)
4893                 {
4894                         // Add the hardlink pointers
4895                         hl->variant.hardLinkVariant.equivalentObject=in;
4896                         list_add(&hl->hardLinks,&in->hardLinks);
4897                 }
4898                 else
4899                 {
4900                         //Todo Need to report/handle this better.
4901                         // Got a problem... hardlink to a non-existant object
4902                         hl->variant.hardLinkVariant.equivalentObject=NULL;
4903                         INIT_LIST_HEAD(&hl->hardLinks);
4904                         
4905                 }
4906                 
4907         }
4908         
4909         {
4910                 struct list_head *i;    
4911                 struct list_head *n;
4912                         
4913                 yaffs_Object *l;
4914                 // Soft delete all the unlinked files
4915                 list_for_each_safe(i,n,&dev->unlinkedDir->variant.directoryVariant.children)
4916                 {
4917                         if(i)
4918                         {
4919                                 l = list_entry(i, yaffs_Object,siblings);
4920                                 yaffs_DestroyObject(l);         
4921                         }
4922                 }       
4923         }
4924         
4925         yaffs_ReleaseTempBuffer(dev,chunkData,__LINE__);
4926
4927         T(YAFFS_TRACE_SCAN,(TSTR("yaffs_Scan ends" TENDSTR)));
4928
4929         return YAFFS_OK;
4930 }
4931
4932
4933 static int yaffs_ScanBackwards(yaffs_Device *dev)
4934 {
4935         yaffs_ExtendedTags tags;
4936         int blk;
4937         int blockIterator;
4938         int startIterator;
4939         int endIterator;
4940         int nBlocksToScan = 0;
4941         
4942         int chunk;
4943         int c;
4944         int deleted;
4945         yaffs_BlockState state;
4946         yaffs_Object *hardList = NULL;
4947         yaffs_Object *hl;
4948         yaffs_BlockInfo *bi;
4949         int sequenceNumber;     
4950         yaffs_ObjectHeader *oh;
4951         yaffs_Object *in;
4952         yaffs_Object *parent;
4953         int nBlocks = dev->internalEndBlock - dev->internalStartBlock + 1;
4954         
4955         __u8 *chunkData;
4956
4957         yaffs_BlockIndex *blockIndex = NULL;
4958
4959
4960         if(!dev->isYaffs2)
4961         {
4962                 T(YAFFS_TRACE_SCAN,(TSTR("yaffs_ScanBackwards is only for YAFFS2!" TENDSTR)));
4963                 return YAFFS_FAIL;
4964         }
4965         
4966         T(YAFFS_TRACE_SCAN,(TSTR("yaffs_ScanBackwards starts  intstartblk %d intendblk %d..." TENDSTR),dev->internalStartBlock,dev->internalEndBlock));
4967                 
4968         chunkData = yaffs_GetTempBuffer(dev,__LINE__);
4969         
4970         
4971         dev->sequenceNumber = YAFFS_LOWEST_SEQUENCE_NUMBER;
4972         
4973         blockIndex = YMALLOC(nBlocks * sizeof(yaffs_BlockIndex));               
4974         
4975         
4976         // Scan all the blocks to determine their state
4977         for(blk = dev->internalStartBlock; blk <= dev->internalEndBlock; blk++)
4978         {
4979                 bi = yaffs_GetBlockInfo(dev,blk);
4980                 yaffs_ClearChunkBits(dev,blk);
4981                 bi->pagesInUse = 0;
4982                 bi->softDeletions = 0;
4983                                 
4984                 yaffs_QueryInitialBlockState(dev,blk,&state,&sequenceNumber);
4985                 
4986                 bi->blockState = state;
4987                 bi->sequenceNumber = sequenceNumber;
4988
4989                 T(YAFFS_TRACE_SCAN_DEBUG,(TSTR("Block scanning block %d state %d seq %d" TENDSTR),blk,state,sequenceNumber));
4990                 
4991                 if(state == YAFFS_BLOCK_STATE_DEAD)
4992                 {
4993                         T(YAFFS_TRACE_BAD_BLOCKS,(TSTR("block %d is bad" TENDSTR),blk));
4994                 }
4995                 else if(state == YAFFS_BLOCK_STATE_EMPTY)
4996                 {
4997                         T(YAFFS_TRACE_SCAN_DEBUG,(TSTR("Block empty " TENDSTR)));
4998                         dev->nErasedBlocks++;
4999                         dev->nFreeChunks += dev->nChunksPerBlock;
5000                 }
5001                 else if(state == YAFFS_BLOCK_STATE_NEEDS_SCANNING)
5002                 {
5003                                         
5004                         // Determine the highest sequence number
5005                         if( dev->isYaffs2 &&
5006                             sequenceNumber >= YAFFS_LOWEST_SEQUENCE_NUMBER &&
5007                             sequenceNumber < YAFFS_HIGHEST_SEQUENCE_NUMBER)
5008                          {
5009                                 
5010                                 blockIndex[nBlocksToScan].seq = sequenceNumber;
5011                                 blockIndex[nBlocksToScan].block = blk;
5012                                 
5013                                 nBlocksToScan++;
5014
5015                                 if(sequenceNumber >= dev->sequenceNumber)
5016                                 {
5017                                         dev->sequenceNumber = sequenceNumber;
5018                                 }
5019                         }
5020                         else if(dev->isYaffs2)
5021                         {
5022                                 // TODO: Nasty sequence number!
5023                                 T(YAFFS_TRACE_SCAN,(TSTR("Block scanning block %d has bad sequence number %d" TENDSTR),blk,sequenceNumber));
5024
5025                         }
5026                 }
5027         }
5028         
5029         // Sort the blocks
5030         // Dungy old bubble sort for now...
5031         {
5032                 yaffs_BlockIndex temp;
5033                 int i;
5034                 int j;
5035                 
5036                 for(i = 0; i < nBlocksToScan; i++)
5037                         for(j = i+1; j < nBlocksToScan; j++)
5038                          if(blockIndex[i].seq > blockIndex[j].seq)
5039                          {
5040                                 temp = blockIndex[j];
5041                                 blockIndex[j] = blockIndex[i];
5042                                 blockIndex[i] = temp;
5043                          }
5044         }
5045         
5046         
5047         // Now scan the blocks looking at the data.
5048         startIterator = 0;
5049         endIterator = nBlocksToScan-1;
5050         T(YAFFS_TRACE_SCAN_DEBUG,(TSTR("%d blocks to be scanned" TENDSTR),nBlocksToScan));
5051
5052         
5053         // For each block.... backwards
5054         for(blockIterator = endIterator; blockIterator >= startIterator; blockIterator--)
5055         {
5056         
5057                 // get the block to scan in the correct order
5058                 blk = blockIndex[blockIterator].block;
5059
5060
5061                 bi = yaffs_GetBlockInfo(dev,blk);
5062                 state = bi->blockState;
5063                 
5064                 deleted = 0;
5065                 
5066                 if( 0 && // Disable since this is redundant.
5067                     state == YAFFS_BLOCK_STATE_NEEDS_SCANNING)
5068                 {
5069                         // Let's look at the first chunk in the block
5070                         chunk = blk * dev->nChunksPerBlock;
5071                         
5072                         yaffs_ReadChunkWithTagsFromNAND(dev,chunk,NULL,&tags);
5073
5074                         // Let's have a good look at this chunk...
5075         
5076                         if(!tags.chunkUsed)
5077                         {
5078                                 // An unassigned chunk in the block
5079                                 // This means that either the block is empty or 
5080                                 // this is the one being allocated from
5081                                 
5082                                 // We're looking at the first chunk in the block so the block is unused
5083                                 state = YAFFS_BLOCK_STATE_EMPTY;
5084                                 dev->nErasedBlocks++;
5085                                 dev->nFreeChunks += dev->nChunksPerBlock;
5086                         }
5087                 
5088                 }
5089                 
5090                 // For each chunk in each block that needs scanning....
5091                 for(c = dev->nChunksPerBlock-1; c >= 0 && 
5092                                   (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING ||
5093                                    state == YAFFS_BLOCK_STATE_ALLOCATING); c--)
5094                 {
5095                         // Scan backwards... 
5096                         // Read the tags and decide what to do
5097                         chunk = blk * dev->nChunksPerBlock + c;
5098                         
5099                         yaffs_ReadChunkWithTagsFromNAND(dev,chunk,NULL,&tags);
5100
5101                         // Let's have a good look at this chunk...
5102         
5103                         if(!tags.chunkUsed)
5104                         {
5105                                 // An unassigned chunk in the block
5106                                 // This means that either the block is empty or 
5107                                 // this is the one being allocated from
5108                                 
5109                                 if(c == 0)
5110                                 {
5111                                         // We're looking at the first chunk in the block so the block is unused
5112                                         state = YAFFS_BLOCK_STATE_EMPTY;
5113                                         dev->nErasedBlocks++;
5114                                 }
5115                                 else
5116                                 {
5117                                         // this is the block being allocated from
5118                                         if(state == YAFFS_BLOCK_STATE_NEEDS_SCANNING)
5119                                         {
5120                                           T(YAFFS_TRACE_SCAN,(TSTR(" Allocating from %d %d" TENDSTR),blk,c));
5121                                         }
5122                                         state = YAFFS_BLOCK_STATE_ALLOCATING;
5123                                         dev->allocationBlock = blk;
5124                                         dev->allocationPage = c;
5125                                         dev->allocationBlockFinder = blk; // Set it to here to encourage the allocator to
5126                                                                                                           // go forth from here.
5127                                         //Yaffs2 sanity check:
5128                                         // This should be the one with the highest sequence number
5129                                         if(dev->isYaffs2 && (dev->sequenceNumber != bi->sequenceNumber))
5130                                         {
5131                                                 T(YAFFS_TRACE_ALWAYS,
5132                                                                 (TSTR("yaffs: Allocation block %d was not highest sequence id: block seq = %d, dev seq = %d" TENDSTR),
5133                                                                 blk,bi->sequenceNumber,dev->sequenceNumber));
5134                                         }
5135                                 }
5136
5137                                 dev->nFreeChunks ++;
5138                         }
5139                         else if(tags.chunkId > 0)
5140                         {
5141                                 // chunkId > 0 so it is a data chunk...
5142                                 unsigned int endpos;
5143                                 
5144                                 __u32 chunkBase = (tags.chunkId - 1)* dev->nBytesPerChunk;
5145
5146                                 yaffs_SetChunkBit(dev,blk,c);
5147                                 bi->pagesInUse++;
5148                                                                 
5149                                 in = yaffs_FindOrCreateObjectByNumber(dev,tags.objectId,YAFFS_OBJECT_TYPE_FILE);
5150                                 if(in->variantType == YAFFS_OBJECT_TYPE_FILE &&
5151                                    chunkBase < in->variant.fileVariant.shrinkSize)
5152                                 {
5153                                         // This has not been invalidated by a resize
5154                                         yaffs_PutChunkIntoFile(in,tags.chunkId,chunk,-1);
5155                                 
5156                                 
5157                                         // File size is calculated by looking at the data chunks if we have not 
5158                                         // seen an object header yet. Stop this practice once we find an object header.
5159                                         endpos = (tags.chunkId - 1)* dev->nBytesPerChunk + tags.byteCount;
5160                                         if(!in->valid && // have not got an object header yet
5161                                            in->variant.fileVariant.scannedFileSize <endpos)
5162                                         {
5163                                                 in->variant.fileVariant.scannedFileSize = endpos;
5164                                                 in->variant.fileVariant.fileSize = in->variant.fileVariant.scannedFileSize;
5165                                         }
5166
5167                                 }
5168                                 else
5169                                 {
5170                                         // This chunk has been invalidated by a resize, so delete
5171                                         yaffs_DeleteChunk(dev,chunk,1,__LINE__);
5172                                         
5173                                         
5174                                 }
5175                                 //T((" %d %d data %d %d\n",blk,c,tags.objectId,tags.chunkId));  
5176                         }
5177                         else
5178                         {
5179                                 // chunkId == 0, so it is an ObjectHeader.
5180                                 // Thus, we read in the object header and make the object
5181                                 yaffs_SetChunkBit(dev,blk,c);
5182                                 bi->pagesInUse++;
5183                                 
5184                                 oh = NULL;
5185                                 in = NULL;
5186                                 
5187                                 if(tags.extraHeaderInfoAvailable)
5188                                 {
5189                                         in = yaffs_FindOrCreateObjectByNumber(dev,tags.objectId,tags.extraObjectType);
5190                                 }
5191
5192                                 
5193                                 if(!in || !in->valid)
5194                                 {
5195                                 
5196                                         // If we don't have  valid info then we need to read the chunk
5197                                         // TODO In future we can probably defer reading the chunk and 
5198                                         // living with invalid data until needed.
5199                                                                 
5200                                         yaffs_ReadChunkWithTagsFromNAND(dev,chunk,chunkData,NULL);
5201                                 
5202                                         oh = (yaffs_ObjectHeader *)chunkData;
5203                                 
5204                                         if(!in)
5205                                            in = yaffs_FindOrCreateObjectByNumber(dev,tags.objectId,oh->type);
5206                                         
5207                                 }
5208                                 
5209                                 if(!in)
5210                                 {
5211                                         // TODO Hoosterman we have a problem!
5212                                         T(YAFFS_TRACE_ERROR, (TSTR("yaffs tragedy: Could not make object for object  %d  at chunk %d during scan" TENDSTR),tags.objectId,chunk));
5213
5214                                 }
5215                                 
5216                                 if(in->valid)
5217                                 {
5218                                         // We have already filled this one. We have a duplicate that will be discarded, but 
5219                                         // we first have to suck out resize info if it is a file.
5220                                         
5221                                         if( (in->variantType == YAFFS_OBJECT_TYPE_FILE) &&
5222                                             ((oh && oh->type == YAFFS_OBJECT_TYPE_FILE) ||
5223                                             (tags.extraHeaderInfoAvailable && tags.extraObjectType == YAFFS_OBJECT_TYPE_FILE))
5224                                            )
5225                                         {
5226                                                 __u32 thisSize = (oh) ? oh->fileSize : tags.extraFileLength;
5227                                                 __u32 parentObjectId = (oh) ? oh->parentObjectId : tags.extraParentObjectId;
5228                                                 unsigned isShrink = (oh)  ? oh->isShrink : tags.extraIsShrinkHeader;
5229                                                 
5230                                                 // If it is deleted (unlinked at start also means deleted)
5231                                                 // we treat the file size as being zeroed at this point.
5232                                                 if(parentObjectId == YAFFS_OBJECTID_DELETED ||
5233                                                    parentObjectId == YAFFS_OBJECTID_UNLINKED)
5234                                                 {
5235                                                         thisSize = 0;
5236                                                         isShrink = 1;
5237                                                 }
5238                                                                                                 
5239                                                 if(in->variant.fileVariant.shrinkSize > thisSize)
5240                                                 {
5241                                                         in->variant.fileVariant.shrinkSize = thisSize;
5242                                                 }
5243                                                 
5244                                                 if(isShrink)
5245                                                 {
5246                                                         bi->hasShrinkHeader = 1;
5247                                                 }
5248                                                 
5249                                         }
5250                                         // Use existing - destroy this one.
5251                                         yaffs_DeleteChunk(dev,chunk,1,__LINE__);
5252                 
5253                                 }
5254                                 
5255                                 if(!in->valid &&
5256                                    (tags.objectId == YAFFS_OBJECTID_ROOT ||
5257                                     tags.objectId == YAFFS_OBJECTID_LOSTNFOUND))
5258                                 {
5259                                         // We only load some info, don't fiddle with directory structure
5260                                         in->valid = 1;
5261                                         in->variantType = oh->type;
5262         
5263                                         in->yst_mode  = oh->yst_mode;
5264 #ifdef CONFIG_YAFFS_WINCE
5265                                         in->win_atime[0] = oh->win_atime[0];
5266                                         in->win_ctime[0] = oh->win_ctime[0];
5267                                         in->win_mtime[0] = oh->win_mtime[0];
5268                                         in->win_atime[1] = oh->win_atime[1];
5269                                         in->win_ctime[1] = oh->win_ctime[1];
5270                                         in->win_mtime[1] = oh->win_mtime[1];
5271 #else
5272                                         in->yst_uid   = oh->yst_uid;
5273                                         in->yst_gid   = oh->yst_gid;
5274                                         in->yst_atime = oh->yst_atime;
5275                                         in->yst_mtime = oh->yst_mtime;
5276                                         in->yst_ctime = oh->yst_ctime;
5277                                         in->yst_rdev = oh->yst_rdev;
5278 #endif
5279                                         in->chunkId  = chunk;
5280
5281                                 }
5282                                 else if(!in->valid)
5283                                 {
5284                                         // we need to load this info
5285                                 
5286                                         in->valid = 1;
5287                                         in->variantType = oh->type;
5288         
5289                                         in->yst_mode  = oh->yst_mode;
5290 #ifdef CONFIG_YAFFS_WINCE
5291                                         in->win_atime[0] = oh->win_atime[0];
5292                                         in->win_ctime[0] = oh->win_ctime[0];
5293                                         in->win_mtime[0] = oh->win_mtime[0];
5294                                         in->win_atime[1] = oh->win_atime[1];
5295                                         in->win_ctime[1] = oh->win_ctime[1];
5296                                         in->win_mtime[1] = oh->win_mtime[1];
5297 #else
5298                                         in->yst_uid   = oh->yst_uid;
5299                                         in->yst_gid   = oh->yst_gid;
5300                                         in->yst_atime = oh->yst_atime;
5301                                         in->yst_mtime = oh->yst_mtime;
5302                                         in->yst_ctime = oh->yst_ctime;
5303                                         in->yst_rdev = oh->yst_rdev;
5304 #endif
5305                                         in->chunkId  = chunk;
5306
5307                                         yaffs_SetObjectName(in,oh->name);
5308                                         in->dirty = 0;
5309                                                         
5310                                         // directory stuff...
5311                                         // hook up to parent
5312         
5313                                         parent = yaffs_FindOrCreateObjectByNumber(dev,oh->parentObjectId,YAFFS_OBJECT_TYPE_DIRECTORY);
5314                                         if(parent->variantType == YAFFS_OBJECT_TYPE_UNKNOWN)
5315                                         {
5316                                                 // Set up as a directory
5317                                                 parent->variantType = YAFFS_OBJECT_TYPE_DIRECTORY;
5318                                                 INIT_LIST_HEAD(&parent->variant.directoryVariant.children);
5319                                         }
5320                                         else if(parent->variantType != YAFFS_OBJECT_TYPE_DIRECTORY)
5321                                         {
5322                                                 // Hoosterman, another problem....
5323                                                 // We're trying to use a non-directory as a directory
5324
5325                                                 T(YAFFS_TRACE_ERROR, (TSTR("yaffs tragedy: attempting to use non-directory as a directory in scan. Put in lost+found." TENDSTR)));
5326                                                 parent = dev->lostNFoundDir;
5327                                         }
5328                                 
5329                                         yaffs_AddObjectToDirectory(parent,in);
5330
5331                                         if((parent == dev->deletedDir ||
5332                                            parent == dev->unlinkedDir))
5333                                         {
5334                                                 in->deleted = 1; // If it is unlinked at start up then it wants deleting
5335                                         }
5336                                         
5337                                         if( oh->isShrink)
5338                                         {
5339                                                 // Mark the block as having a shrinkHeader
5340                                                 bi->hasShrinkHeader = 1;
5341                                         }
5342                                         
5343                                 
5344                                         // Note re hardlinks.
5345                                         // Since we might scan a hardlink before its equivalent object is scanned
5346                                         // we put them all in a list.
5347                                         // After scanning is complete, we should have all the objects, so we run through this
5348                                         // list and fix up all the chains.              
5349         
5350                                         switch(in->variantType)
5351                                         {
5352                                                 case YAFFS_OBJECT_TYPE_UNKNOWN:         // Todo got a problem
5353                                                         break;
5354                                                 case YAFFS_OBJECT_TYPE_FILE:
5355
5356                                                         
5357                                                         if(in->variant.fileVariant.scannedFileSize < oh->fileSize)
5358                                                         {
5359                                                                 in->variant.fileVariant.fileSize = oh->fileSize;
5360                                                                 in->variant.fileVariant.scannedFileSize = in->variant.fileVariant.fileSize;
5361                                                         }
5362                                                         
5363                                                                                                         
5364                                                         
5365                                                         if(in->variant.fileVariant.shrinkSize > oh->fileSize)
5366                                                         {
5367                                                                 in->variant.fileVariant.shrinkSize = oh->fileSize;
5368                                                         }
5369                                                                                                         
5370                                                                 
5371                                                         break;
5372                                                 case YAFFS_OBJECT_TYPE_HARDLINK:
5373                                                         in->variant.hardLinkVariant.equivalentObjectId = oh->equivalentObjectId;
5374                                                         in->hardLinks.next = (struct list_head *)hardList;
5375                                                         hardList = in;
5376                                                         break;
5377                                                 case YAFFS_OBJECT_TYPE_DIRECTORY:       // Do nothing
5378                                                         break;
5379                                                 case YAFFS_OBJECT_TYPE_SPECIAL: // Do nothing
5380                                                         break;
5381                                                 case YAFFS_OBJECT_TYPE_SYMLINK:         // Do nothing
5382                                                         in->variant.symLinkVariant.alias = yaffs_CloneString(oh->alias);
5383                                                         break;
5384                                         }
5385
5386 #if 0
5387                                         if(parent == dev->deletedDir)
5388                                         {
5389                                                 yaffs_DestroyObject(in);
5390                                                 bi->hasShrinkHeader = 1;
5391                                         }
5392 #endif
5393                                         //T((" %d %d header %d \"%s\" type %d\n",blk,c,tags.objectId,oh->name,in->variantType));        
5394                                 }
5395                         }
5396                 }
5397                 
5398                 if(state == YAFFS_BLOCK_STATE_NEEDS_SCANNING)
5399                 {
5400                         // If we got this far while scanning, then the block is fully allocated.
5401                         state = YAFFS_BLOCK_STATE_FULL; 
5402                 }
5403                 
5404                 bi->blockState = state;
5405                 
5406                 // Now let's see if it was dirty
5407                 if(     bi->pagesInUse == 0 &&
5408                         !bi->hasShrinkHeader &&
5409                 bi->blockState == YAFFS_BLOCK_STATE_FULL)
5410             {
5411                 yaffs_BlockBecameDirty(dev,blk);
5412             }
5413
5414         }
5415         
5416         if(blockIndex)
5417         {
5418                 YFREE(blockIndex);
5419         }
5420         
5421         // Ok, we've done all the scanning.
5422         
5423         // Fix up the hard link chains.
5424         // We should now have scanned all the objects, now it's time to add these 
5425         // hardlinks.
5426         while(hardList)
5427         {
5428                 hl = hardList;
5429                 hardList = (yaffs_Object *)(hardList->hardLinks.next);
5430                 
5431                 in = yaffs_FindObjectByNumber(dev,hl->variant.hardLinkVariant.equivalentObjectId);
5432                 
5433                 if(in)
5434                 {
5435                         // Add the hardlink pointers
5436                         hl->variant.hardLinkVariant.equivalentObject=in;
5437                         list_add(&hl->hardLinks,&in->hardLinks);
5438                 }
5439                 else
5440                 {
5441                         //Todo Need to report/handle this better.
5442                         // Got a problem... hardlink to a non-existant object
5443                         hl->variant.hardLinkVariant.equivalentObject=NULL;
5444                         INIT_LIST_HEAD(&hl->hardLinks);
5445                         
5446                 }
5447                 
5448         }
5449         
5450         {
5451                 struct list_head *i;    
5452                 struct list_head *n;
5453                         
5454                 yaffs_Object *l;
5455                 
5456                 // Soft delete all the unlinked files
5457                 list_for_each_safe(i,n,&dev->unlinkedDir->variant.directoryVariant.children)
5458                 {
5459                         if(i)
5460                         {
5461                                 l = list_entry(i, yaffs_Object,siblings);
5462                                 yaffs_DestroyObject(l);         
5463                         }
5464                 }       
5465                 
5466                 // Soft delete all the deletedDir files
5467                 list_for_each_safe(i,n,&dev->deletedDir->variant.directoryVariant.children)
5468                 {
5469                         if(i)
5470                         {
5471                                 l = list_entry(i, yaffs_Object,siblings);
5472                                 yaffs_DestroyObject(l);         
5473                                 
5474                         }
5475                 }       
5476         }
5477         
5478         yaffs_ReleaseTempBuffer(dev,chunkData,__LINE__);
5479
5480         T(YAFFS_TRACE_SCAN,(TSTR("yaffs_ScanBackwards ends" TENDSTR)));
5481
5482         return YAFFS_OK;
5483 }
5484
5485
5486
5487 ////////////////////////// Directory Functions /////////////////////////
5488
5489
5490 static void yaffs_AddObjectToDirectory(yaffs_Object *directory, yaffs_Object *obj)
5491 {
5492
5493         if(!directory)
5494         {
5495                 T(YAFFS_TRACE_ALWAYS,(TSTR("tragedy: Trying to add an object to a null pointer directory" TENDSTR)));
5496                 YBUG();
5497         }
5498         if(directory->variantType != YAFFS_OBJECT_TYPE_DIRECTORY)
5499         {
5500                 T(YAFFS_TRACE_ALWAYS,(TSTR("tragedy: Trying to add an object to a non-directory" TENDSTR)));
5501                 YBUG();
5502         }
5503
5504                 if(obj->siblings.prev == NULL)
5505         {
5506                 // Not initialised
5507                 INIT_LIST_HEAD(&obj->siblings);
5508                 
5509         }
5510         else if(!list_empty(&obj->siblings))
5511         {
5512                 // If it is holed up somewhere else, un hook it
5513                 list_del_init(&obj->siblings);
5514         }
5515         // Now add it
5516         list_add(&obj->siblings,&directory->variant.directoryVariant.children);
5517         obj->parent = directory;
5518         
5519         if(directory == obj->myDev->unlinkedDir || directory == obj->myDev->deletedDir)
5520         {
5521                 obj->unlinked = 1;
5522                 obj->myDev->nUnlinkedFiles++;
5523                 obj->renameAllowed = 0;
5524         }
5525 }
5526
5527 static void yaffs_RemoveObjectFromDirectory(yaffs_Object *obj)
5528 {
5529         list_del_init(&obj->siblings);
5530         obj->parent = NULL;
5531 }
5532
5533 yaffs_Object *yaffs_FindObjectByName(yaffs_Object *directory,const YCHAR *name)
5534 {
5535         int sum;
5536         
5537         struct list_head *i;
5538         YCHAR buffer[YAFFS_MAX_NAME_LENGTH+1];
5539         
5540         yaffs_Object *l;
5541         
5542
5543         if(!directory)
5544         {
5545                 T(YAFFS_TRACE_ALWAYS,(TSTR("tragedy: yaffs_FindObjectByName: null pointer directory"TENDSTR)));
5546                 YBUG();
5547         }
5548         if(directory->variantType != YAFFS_OBJECT_TYPE_DIRECTORY)
5549         {
5550                 T(YAFFS_TRACE_ALWAYS,(TSTR("tragedy: yaffs_FindObjectByName: non-directory"TENDSTR)));
5551                 YBUG();
5552         }
5553
5554         sum = yaffs_CalcNameSum(name);
5555         
5556         list_for_each(i,&directory->variant.directoryVariant.children)
5557         {
5558                 if(i)
5559                 {
5560                         l = list_entry(i, yaffs_Object,siblings);
5561                 
5562                         // Special case for lost-n-found
5563                         if(l->objectId == YAFFS_OBJECTID_LOSTNFOUND)
5564                         {
5565                                 if(yaffs_strcmp(name,YAFFS_LOSTNFOUND_NAME) == 0)
5566                                 {
5567                                         return l;
5568                                 }
5569                         }
5570                         else if(yaffs_SumCompare(l->sum, sum)||
5571                                     l->chunkId <= 0) //LostnFound cunk called Objxxx
5572                         {
5573                                 // Do a real check
5574                                 yaffs_GetObjectName(l,buffer,YAFFS_MAX_NAME_LENGTH);
5575                                 if(yaffs_strcmp(name,buffer) == 0)
5576                                 {
5577                                         return l;
5578                                 }
5579                         
5580                         }                       
5581                 }
5582         }
5583         
5584         return NULL;
5585 }
5586
5587
5588 int yaffs_ApplyToDirectoryChildren(yaffs_Object *theDir,int (*fn)(yaffs_Object *))
5589 {
5590         struct list_head *i;    
5591         yaffs_Object *l;
5592         
5593
5594         if(!theDir)
5595         {
5596                 T(YAFFS_TRACE_ALWAYS,(TSTR("tragedy: yaffs_FindObjectByName: null pointer directory"TENDSTR)));
5597                 YBUG();
5598         }
5599         if(theDir->variantType != YAFFS_OBJECT_TYPE_DIRECTORY)
5600         {
5601                 T(YAFFS_TRACE_ALWAYS,(TSTR("tragedy: yaffs_FindObjectByName: non-directory"TENDSTR)));
5602                 YBUG();
5603         }
5604         
5605         list_for_each(i,&theDir->variant.directoryVariant.children)
5606         {
5607                 if(i)
5608                 {
5609                         l = list_entry(i, yaffs_Object,siblings);
5610                         if(l && !fn(l))
5611                         {
5612                                 return YAFFS_FAIL;
5613                         }
5614                 }
5615         }
5616         
5617         return YAFFS_OK;
5618
5619 }
5620
5621
5622 // GetEquivalentObject dereferences any hard links to get to the
5623 // actual object.
5624
5625 yaffs_Object *yaffs_GetEquivalentObject(yaffs_Object *obj)
5626 {
5627         if(obj && obj->variantType == YAFFS_OBJECT_TYPE_HARDLINK)
5628         {
5629                 // We want the object id of the equivalent object, not this one
5630                 obj = obj->variant.hardLinkVariant.equivalentObject;
5631         }
5632         return obj;
5633
5634 }
5635
5636 int yaffs_GetObjectName(yaffs_Object *obj,YCHAR *name,int buffSize)
5637 {
5638         memset(name,0,buffSize * sizeof(YCHAR));
5639         
5640         if(obj->objectId == YAFFS_OBJECTID_LOSTNFOUND)
5641         {
5642                 yaffs_strncpy(name,YAFFS_LOSTNFOUND_NAME,buffSize - 1);
5643         }
5644         else if(obj->chunkId <= 0)
5645         {
5646                 YCHAR locName[20];
5647                 // make up a name
5648                 yaffs_sprintf(locName,_Y("%s%d"),YAFFS_LOSTNFOUND_PREFIX,obj->objectId);
5649                 yaffs_strncpy(name,locName,buffSize - 1);
5650
5651         }
5652 #ifdef CONFIG_YAFFS_SHORT_NAMES_IN_RAM
5653         else if(obj->shortName[0])
5654         {
5655                 yaffs_strcpy(name,obj->shortName);
5656         }
5657 #endif
5658         else
5659         {
5660                 __u8 *buffer = yaffs_GetTempBuffer(obj->myDev,__LINE__);
5661                 
5662                 yaffs_ObjectHeader *oh = (yaffs_ObjectHeader *)buffer;
5663
5664                 memset(buffer,0,obj->myDev->nBytesPerChunk);
5665         
5666                 if(obj->chunkId >= 0)
5667                 {
5668                         yaffs_ReadChunkWithTagsFromNAND(obj->myDev,obj->chunkId,buffer,NULL);
5669                 }
5670                 yaffs_strncpy(name,oh->name,buffSize - 1);
5671
5672                 yaffs_ReleaseTempBuffer(obj->myDev,buffer,__LINE__);
5673         }
5674         
5675         return yaffs_strlen(name);
5676 }
5677
5678 int yaffs_GetObjectFileLength(yaffs_Object *obj)
5679 {
5680         
5681         // Dereference any hard linking
5682         obj = yaffs_GetEquivalentObject(obj);
5683         
5684         if(obj->variantType == YAFFS_OBJECT_TYPE_FILE)
5685         {
5686                 return obj->variant.fileVariant.fileSize;
5687         }
5688         if(obj->variantType == YAFFS_OBJECT_TYPE_SYMLINK)
5689         {
5690                 return yaffs_strlen(obj->variant.symLinkVariant.alias);
5691         }
5692         else
5693         {
5694                 // Only a directory should drop through to here
5695                 return obj->myDev->nBytesPerChunk;
5696         }       
5697 }
5698
5699 int yaffs_GetObjectLinkCount(yaffs_Object *obj)
5700 {
5701         int count = 0; 
5702         struct list_head *i;
5703         
5704         if(!obj->unlinked)
5705         {
5706                 count++;        // the object itself
5707         }
5708         list_for_each(i,&obj->hardLinks)
5709         {
5710                 count++;        // add the hard links;
5711         }
5712         return count;
5713         
5714 }
5715
5716
5717 int yaffs_GetObjectInode(yaffs_Object *obj)
5718 {
5719         obj = yaffs_GetEquivalentObject(obj);
5720         
5721         return obj->objectId;
5722 }
5723
5724 unsigned yaffs_GetObjectType(yaffs_Object *obj)
5725 {
5726         obj = yaffs_GetEquivalentObject(obj);
5727         
5728         switch(obj->variantType)
5729         {
5730                 case YAFFS_OBJECT_TYPE_FILE:            return DT_REG; break;
5731                 case YAFFS_OBJECT_TYPE_DIRECTORY:       return DT_DIR; break;
5732                 case YAFFS_OBJECT_TYPE_SYMLINK:         return DT_LNK; break;
5733                 case YAFFS_OBJECT_TYPE_HARDLINK:        return DT_REG; break;
5734                 case YAFFS_OBJECT_TYPE_SPECIAL:         
5735                         if(S_ISFIFO(obj->yst_mode)) return DT_FIFO;
5736                         if(S_ISCHR(obj->yst_mode)) return DT_CHR;
5737                         if(S_ISBLK(obj->yst_mode)) return DT_BLK;
5738                         if(S_ISSOCK(obj->yst_mode)) return DT_SOCK;
5739                 default: return DT_REG; break;
5740         }
5741 }
5742
5743 YCHAR *yaffs_GetSymlinkAlias(yaffs_Object *obj)
5744 {
5745         obj = yaffs_GetEquivalentObject(obj);
5746         if(obj->variantType == YAFFS_OBJECT_TYPE_SYMLINK)
5747         {
5748                 return yaffs_CloneString(obj->variant.symLinkVariant.alias);
5749         }
5750         else
5751         {
5752                 return yaffs_CloneString(_Y(""));
5753         }
5754 }
5755
5756 #ifndef CONFIG_YAFFS_WINCE
5757
5758 int yaffs_SetAttributes(yaffs_Object *obj, struct iattr *attr)
5759 {
5760         unsigned int valid = attr->ia_valid;
5761         
5762         if(valid & ATTR_MODE) obj->yst_mode = attr->ia_mode;
5763         if(valid & ATTR_UID) obj->yst_uid = attr->ia_uid;
5764         if(valid & ATTR_GID) obj->yst_gid = attr->ia_gid;
5765         
5766         if(valid & ATTR_ATIME) obj->yst_atime = Y_TIME_CONVERT(attr->ia_atime);
5767         if(valid & ATTR_CTIME) obj->yst_ctime = Y_TIME_CONVERT(attr->ia_ctime);
5768         if(valid & ATTR_MTIME) obj->yst_mtime = Y_TIME_CONVERT(attr->ia_mtime);
5769         
5770         if(valid & ATTR_SIZE) yaffs_ResizeFile(obj,attr->ia_size);
5771         
5772         yaffs_UpdateObjectHeader(obj,NULL,1,0);
5773         
5774         return YAFFS_OK;
5775         
5776 }
5777 int yaffs_GetAttributes(yaffs_Object *obj, struct iattr *attr)
5778 {
5779         unsigned int valid = 0;
5780         
5781         attr->ia_mode = obj->yst_mode;  valid |= ATTR_MODE;
5782         attr->ia_uid = obj->yst_uid;            valid |= ATTR_UID;
5783         attr->ia_gid = obj->yst_gid;            valid |= ATTR_GID;
5784         
5785         Y_TIME_CONVERT(attr->ia_atime)= obj->yst_atime; valid |= ATTR_ATIME;
5786         Y_TIME_CONVERT(attr->ia_ctime) = obj->yst_ctime;        valid |= ATTR_CTIME;
5787         Y_TIME_CONVERT(attr->ia_mtime) = obj->yst_mtime;        valid |= ATTR_MTIME;
5788
5789         attr->ia_size = yaffs_GetFileSize(obj); valid |= ATTR_SIZE;
5790         
5791         attr->ia_valid = valid;
5792         
5793         return YAFFS_OK;
5794         
5795 }
5796
5797 #endif
5798
5799 int yaffs_DumpObject(yaffs_Object *obj)
5800 {
5801 //      __u8 buffer[YAFFS_BYTES_PER_CHUNK];
5802         YCHAR name[257];
5803 //      yaffs_ObjectHeader *oh = (yaffs_ObjectHeader *)buffer;
5804
5805 //      memset(buffer,0,YAFFS_BYTES_PER_CHUNK);
5806         
5807 //      if(obj->chunkId >= 0)
5808 //      {
5809 //              yaffs_ReadChunkFromNAND(obj->myDev,obj->chunkId,buffer,NULL);
5810 //      }
5811         
5812         yaffs_GetObjectName(obj,name,256);
5813         
5814         T(YAFFS_TRACE_ALWAYS,(TSTR("Object %d, inode %d \"%s\"\n dirty %d valid %d serial %d sum %d chunk %d type %d size %d\n" TENDSTR),
5815                         obj->objectId,yaffs_GetObjectInode(obj), name, obj->dirty, obj->valid, obj->serial, 
5816                         obj->sum, obj->chunkId, yaffs_GetObjectType(obj), yaffs_GetObjectFileLength(obj)));
5817
5818 #if 0
5819         YPRINTF(("Object %d \"%s\"\n dirty %d valid %d serial %d sum %d chunk %d\n",
5820                         obj->objectId, oh->name, obj->dirty, obj->valid, obj->serial, 
5821                         obj->sum, obj->chunkId));
5822                 switch(obj->variantType)
5823         {
5824                 case YAFFS_OBJECT_TYPE_FILE: 
5825                         YPRINTF((" FILE length %d\n",obj->variant.fileVariant.fileSize));
5826                         break;
5827                 case YAFFS_OBJECT_TYPE_DIRECTORY:
5828                         YPRINTF((" DIRECTORY\n"));
5829                         break;
5830                 case YAFFS_OBJECT_TYPE_HARDLINK: //todo
5831                 case YAFFS_OBJECT_TYPE_SYMLINK:
5832                 case YAFFS_OBJECT_TYPE_UNKNOWN:
5833                 default:
5834         }
5835 #endif
5836         
5837         return YAFFS_OK;
5838 }
5839
5840
5841 ///////////////////////// Initialisation code ///////////////////////////
5842
5843
5844 int yaffs_CheckDevFunctions(const yaffs_Device *dev)
5845 {
5846
5847         // Common functions, gotta have
5848         if(!dev->eraseBlockInNAND ||
5849            !dev->initialiseNAND) return 0;
5850
5851 #ifdef CONFIG_YAFFS_YAFFS2
5852
5853         // Can use the "with tags" style interface for yaffs1 or yaffs2
5854         if(dev->writeChunkWithTagsToNAND &&
5855            dev->readChunkWithTagsFromNAND &&
5856            !dev->writeChunkToNAND &&
5857            !dev->readChunkFromNAND &&
5858            dev->markNANDBlockBad &&
5859            dev->queryNANDBlock) return 1;
5860 #endif
5861
5862         // Can use the "spare" style interface for yaffs1
5863         if(!dev->isYaffs2 &&
5864            !dev->writeChunkWithTagsToNAND &&
5865            !dev->readChunkWithTagsFromNAND &&
5866            dev->writeChunkToNAND &&
5867            dev->readChunkFromNAND &&
5868            !dev->markNANDBlockBad &&
5869            !dev->queryNANDBlock) return 1;
5870
5871         return 0; // bad
5872 }
5873
5874
5875 int yaffs_GutsInitialise(yaffs_Device *dev)
5876 {
5877         unsigned x;
5878         int bits;
5879         int extraBits;
5880         int nBlocks;
5881
5882         T(YAFFS_TRACE_ALWAYS,(TSTR("yaffs: yaffs_GutsInitialise()" TENDSTR)));
5883         // Check stuff that must be set
5884
5885         if(!dev)
5886         {
5887                 T(YAFFS_TRACE_ALWAYS,(TSTR("yaffs: Need a device" TENDSTR)));
5888                 return YAFFS_FAIL;
5889         }
5890         
5891         dev->internalStartBlock = dev->startBlock;
5892         dev->internalEndBlock =  dev->endBlock;
5893         dev->blockOffset = 0;
5894         dev->chunkOffset = 0;
5895         dev->nFreeChunks = 0;
5896         
5897         if(dev->startBlock == 0)
5898         {
5899                 dev->internalStartBlock = dev->startBlock + 1;
5900                 dev->internalEndBlock =  dev->endBlock + 1;
5901                 dev->blockOffset = 1;
5902                 dev->chunkOffset = dev->nChunksPerBlock;
5903         }
5904
5905         // Check geometry parameters.
5906
5907         if(     (dev->isYaffs2 && dev->nBytesPerChunk <1024)  ||
5908                 (!dev->isYaffs2 && dev->nBytesPerChunk !=512)  ||
5909                 dev->nChunksPerBlock < 2 ||
5910                 dev->nReservedBlocks < 2 ||
5911                 dev->internalStartBlock <= 0 ||
5912                 dev->internalEndBlock <= 0 ||
5913                 dev->internalEndBlock <= (dev->internalStartBlock + dev->nReservedBlocks + 2) // otherwise it is too small
5914           )
5915         {
5916                 T(YAFFS_TRACE_ALWAYS,(TSTR("yaffs: NAND geometry problems: chunk size %d, type is yaffs%s " TENDSTR),
5917                    dev->nBytesPerChunk, dev->isYaffs2 ? "2" : ""));
5918                 return YAFFS_FAIL;
5919         }
5920
5921         if(yaffs_InitialiseNAND(dev) != YAFFS_OK)
5922         {
5923                 T(YAFFS_TRACE_ALWAYS,(TSTR("yaffs: InitialiseNAND failed" TENDSTR)));
5924                 return YAFFS_FAIL;
5925         }
5926
5927         // Got the right mix of functions?
5928         //
5929         if(!yaffs_CheckDevFunctions(dev))
5930         {
5931                 //Function missing
5932                 T(YAFFS_TRACE_ALWAYS,(TSTR("yaffs: device function(s) missing or wrong\n" TENDSTR)));
5933
5934                 return YAFFS_FAIL;
5935         }
5936
5937         // This is really a compilation check.
5938         if(!yaffs_CheckStructures())
5939         {
5940                 T(YAFFS_TRACE_ALWAYS,(TSTR("yaffs_CheckStructures failed\n" TENDSTR)));
5941                 return YAFFS_FAIL;
5942         }
5943
5944         if(dev->isMounted)
5945         {
5946                 T(YAFFS_TRACE_ALWAYS,(TSTR("yaffs: device already mounted\n" TENDSTR)));
5947                 return YAFFS_FAIL;
5948         }
5949
5950         //
5951         //
5952         // Finished with most checks. One or two more checks happen later on too.
5953         //
5954
5955         dev->isMounted = 1;
5956
5957
5958         nBlocks = dev->internalEndBlock - dev->internalStartBlock + 1;
5959
5960
5961
5962         // OK now calculate a few things for the device
5963         // Calculate chunkGroupBits.
5964         // We need to find the next power of 2 > than internalEndBlock
5965         
5966         x = dev->nChunksPerBlock * (dev->internalEndBlock+1);
5967         
5968         for(bits = extraBits = 0; x > 1; bits++)
5969         {
5970                 if(x & 1) extraBits++;
5971                 x >>= 1;
5972         }
5973
5974         if(extraBits > 0) bits++;
5975         
5976         
5977         // Level0 Tnodes are 16 bits, so if the bitwidth of the
5978         // chunk range we're using is greater than 16 we need
5979         // to figure out chunk shift and chunkGroupSize
5980         if(bits <= 16) 
5981         {
5982                 dev->chunkGroupBits = 0;
5983         }
5984         else
5985         {
5986                 dev->chunkGroupBits = bits - 16;
5987         }
5988         
5989         dev->chunkGroupSize = 1 << dev->chunkGroupBits;
5990
5991         if(dev->nChunksPerBlock < dev->chunkGroupSize)
5992         {
5993                 // We have a problem because the soft delete won't work if
5994                 // the chunk group size > chunks per block.
5995                 // This can be remedied by using larger "virtual blocks".
5996                 T(YAFFS_TRACE_ALWAYS,(TSTR("yaffs: chunk group too large\n" TENDSTR)));
5997                 
5998                 return YAFFS_FAIL;
5999         }
6000
6001         
6002         // OK, we've finished verifying the device, lets continue with initialisation
6003         
6004         // More device initialisation
6005         dev->garbageCollections = 0;
6006         dev->passiveGarbageCollections = 0;
6007         dev->currentDirtyChecker = 0;
6008         dev->bufferedBlock = -1;
6009         dev->doingBufferedBlockRewrite = 0;
6010         dev->nDeletedFiles = 0;
6011         dev->nBackgroundDeletions=0;
6012         dev->nUnlinkedFiles = 0;
6013         dev->eccFixed=0;
6014         dev->eccUnfixed=0;
6015         dev->tagsEccFixed=0;
6016         dev->tagsEccUnfixed=0;
6017         dev->nErasureFailures = 0;
6018         dev->nErasedBlocks = 0;
6019         dev->isDoingGC = 0;
6020         
6021         //dev->localBuffer = YMALLOC(dev->nBytesPerChunk);
6022         // Initialise temporary buffers
6023         {
6024                 int i;
6025                 for(i = 0; i < YAFFS_N_TEMP_BUFFERS; i++)
6026                 {
6027                         dev->tempBuffer[i].line = 0; // not in use
6028                         dev->tempBuffer[i].buffer = YMALLOC(dev->nBytesPerChunk);
6029                 }
6030         }
6031         
6032
6033         
6034         yaffs_InitialiseBlocks(dev,nBlocks);
6035         
6036         yaffs_InitialiseTnodes(dev);
6037
6038         yaffs_InitialiseObjects(dev);
6039         
6040         dev->gcCleanupList = YMALLOC(dev->nChunksPerBlock * sizeof(__u32));
6041         
6042         if(dev->nShortOpCaches > 0)
6043         { 
6044                 int i;
6045                 
6046                 if(dev->nShortOpCaches >  YAFFS_MAX_SHORT_OP_CACHES)
6047                 {
6048                         dev->nShortOpCaches = YAFFS_MAX_SHORT_OP_CACHES;
6049                 }
6050                 
6051                 dev->srCache = YMALLOC( dev->nShortOpCaches * sizeof(yaffs_ChunkCache));
6052                 
6053                 for(i=0; i < dev->nShortOpCaches; i++)
6054                 {
6055                         dev->srCache[i].object = NULL;
6056                         dev->srCache[i].lastUse = 0;
6057                         dev->srCache[i].dirty = 0;
6058                         dev->srCache[i].data = YMALLOC(dev->nBytesPerChunk);
6059                 }
6060                 dev->srLastUse = 0;
6061         }
6062
6063         dev->cacheHits = 0;
6064         
6065         
6066         // Initialise the unlinked, root and lost and found directories
6067         dev->lostNFoundDir = dev->rootDir = dev->unlinkedDir = dev->deletedDir = NULL;
6068         
6069         dev->unlinkedDir = yaffs_CreateFakeDirectory(dev,YAFFS_OBJECTID_UNLINKED, S_IFDIR);
6070         dev->deletedDir = yaffs_CreateFakeDirectory(dev,YAFFS_OBJECTID_DELETED, S_IFDIR);
6071
6072         dev->rootDir = yaffs_CreateFakeDirectory(dev,YAFFS_OBJECTID_ROOT,YAFFS_ROOT_MODE | S_IFDIR);
6073         dev->lostNFoundDir = yaffs_CreateFakeDirectory(dev,YAFFS_OBJECTID_LOSTNFOUND,YAFFS_LOSTNFOUND_MODE | S_IFDIR);
6074         yaffs_AddObjectToDirectory(dev->rootDir,dev->lostNFoundDir);
6075         
6076         if(dev->isYaffs2) 
6077         {
6078                 dev->useHeaderFileSize = 1;
6079         }
6080                 
6081         // Now scan the flash.  
6082         
6083         if(dev->isYaffs2)
6084                 yaffs_ScanBackwards(dev);
6085         else
6086                 yaffs_Scan(dev);
6087         
6088         // Zero out stats
6089         dev->nPageReads = 0;
6090         dev->nPageWrites =  0;
6091         dev->nBlockErasures = 0;
6092         dev->nGCCopies = 0;
6093         dev->nRetriedWrites = 0;
6094
6095         dev->nRetiredBlocks = 0;
6096         
6097         yaffs_VerifyFreeChunks(dev);
6098
6099         T(YAFFS_TRACE_ALWAYS,(TSTR("yaffs: yaffs_GutsInitialise() done.\n" TENDSTR)));
6100         return YAFFS_OK;
6101                 
6102 }
6103
6104 void yaffs_Deinitialise(yaffs_Device *dev)
6105 {
6106         if(dev->isMounted)
6107         {
6108                 int i;
6109         
6110                 yaffs_DeinitialiseBlocks(dev);
6111                 yaffs_DeinitialiseTnodes(dev);
6112                 yaffs_DeinitialiseObjects(dev);
6113                 if(dev->nShortOpCaches > 0)
6114                 {
6115                                 
6116                         for(i=0; i < dev->nShortOpCaches; i++)
6117                         {
6118                                 YFREE(dev->srCache[i].data);
6119                         }
6120
6121                         YFREE(dev->srCache);
6122                 }
6123
6124                 YFREE(dev->gcCleanupList);
6125
6126                 for(i = 0; i < YAFFS_N_TEMP_BUFFERS; i++)
6127                 {
6128                         YFREE(dev->tempBuffer[i].buffer);
6129                 }
6130                 
6131                 dev->isMounted = 0;
6132         }
6133         
6134 }
6135
6136 #if 0
6137
6138 int  yaffs_GetNumberOfFreeChunks(yaffs_Device *dev)
6139 {
6140         int nFree = dev->nFreeChunks - (dev->nChunksPerBlock * YAFFS_RESERVED_BLOCKS);
6141         
6142         struct list_head *i;    
6143         yaffs_Object *l;
6144         
6145         
6146         // To the free chunks add the chunks that are in the deleted unlinked files.
6147         list_for_each(i,&dev->deletedDir->variant.directoryVariant.children)
6148         {
6149                 l = list_entry(i, yaffs_Object,siblings);
6150                 if(l->deleted)
6151                 {
6152                         nFree++;
6153                         nFree += l->nDataChunks;
6154                 }
6155         }
6156         
6157         
6158         // printf("___________ nFreeChunks is %d nFree is %d\n",dev->nFreeChunks,nFree);        
6159
6160         if(nFree < 0) nFree = 0;
6161
6162         return nFree;   
6163         
6164 }
6165
6166 #endif
6167
6168 static int  yaffs_CountFreeChunks(yaffs_Device *dev)
6169 {
6170         int nFree;
6171         int b;
6172
6173         yaffs_BlockInfo *blk;   
6174
6175         
6176         for(nFree = 0, b = dev->internalStartBlock; b <= dev->internalEndBlock; b++)
6177         {
6178                 blk = yaffs_GetBlockInfo(dev,b);
6179                 
6180                 switch(blk->blockState)
6181                 {
6182                         case YAFFS_BLOCK_STATE_EMPTY:
6183                         case YAFFS_BLOCK_STATE_ALLOCATING: 
6184                         case YAFFS_BLOCK_STATE_COLLECTING:
6185                         case YAFFS_BLOCK_STATE_FULL: nFree += (dev->nChunksPerBlock - blk->pagesInUse + blk->softDeletions); break;
6186                         default: break;
6187                 }
6188
6189         }
6190         
6191         return nFree;
6192 }       
6193         
6194
6195
6196 int yaffs_GetNumberOfFreeChunks(yaffs_Device *dev)
6197 {
6198         // This is what we report to the outside world
6199
6200         int nFree;
6201         int nDirtyCacheChunks;
6202                 
6203 #if 1   
6204         nFree = dev->nFreeChunks;
6205 #else
6206         nFree = yaffs_CountFreeChunks(dev);
6207 #endif
6208         
6209         // Now count the number of dirty chunks in the cache and subtract those
6210         
6211         {
6212                 int i;
6213                 for( nDirtyCacheChunks = 0,i = 0; i < dev->nShortOpCaches; i++)
6214                 {
6215                         if(dev->srCache[i].dirty) nDirtyCacheChunks++;
6216                 }
6217         }
6218         
6219         nFree -= nDirtyCacheChunks;
6220         
6221         nFree -= ((dev->nReservedBlocks + 1) * dev->nChunksPerBlock);
6222         
6223         if(nFree < 0) nFree = 0;
6224
6225         return nFree;   
6226         
6227 }
6228
6229 static int  yaffs_freeVerificationFailures;
6230
6231 static void yaffs_VerifyFreeChunks(yaffs_Device *dev)
6232 {
6233         int counted = yaffs_CountFreeChunks(dev);
6234         
6235         int difference = dev->nFreeChunks - counted;
6236         
6237         if(difference)
6238         {
6239                 T(YAFFS_TRACE_ALWAYS,(TSTR("Freechunks verification failure %d %d %d" TENDSTR),dev->nFreeChunks,counted,difference)); 
6240                 yaffs_freeVerificationFailures++;       
6241         }
6242 }
6243
6244 /////////////////// YAFFS test code //////////////////////////////////
6245
6246 #define yaffs_CheckStruct(structure,syze, name) \
6247            if(sizeof(structure) != syze) \
6248                { \
6249                  T(YAFFS_TRACE_ALWAYS,(TSTR("%s should be %d but is %d\n" TENDSTR),name,syze,sizeof(structure))); \
6250                  return YAFFS_FAIL; \
6251                    }
6252                  
6253                  
6254 static int yaffs_CheckStructures(void)
6255 {
6256 //      yaffs_CheckStruct(yaffs_Tags,8,"yaffs_Tags")
6257 //      yaffs_CheckStruct(yaffs_TagsUnion,8,"yaffs_TagsUnion")
6258 //      yaffs_CheckStruct(yaffs_Spare,16,"yaffs_Spare")
6259 #ifndef CONFIG_YAFFS_TNODE_LIST_DEBUG
6260         yaffs_CheckStruct(yaffs_Tnode,2* YAFFS_NTNODES_LEVEL0,"yaffs_Tnode")
6261 #endif
6262         yaffs_CheckStruct(yaffs_ObjectHeader,512,"yaffs_ObjectHeader")
6263         
6264         
6265         return YAFFS_OK;
6266 }
6267
6268 #if 0
6269 void yaffs_GutsTest(yaffs_Device *dev)
6270 {
6271         
6272         if(yaffs_CheckStructures() != YAFFS_OK)
6273         {
6274                 T(YAFFS_TRACE_ALWAYS,(TSTR("One or more structures malformed-- aborting\n" TENDSTR)));
6275                 return;
6276         }
6277         
6278         yaffs_TnodeTest(dev);
6279         yaffs_ObjectTest(dev);  
6280 }
6281 #endif
6282
6283