Fix issue with unlinking hardlinks failing sanity check
[yaffs2.git] / yaffs_guts.c
1 /*
2  * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
3  *
4  * Copyright (C) 2002-2007 Aleph One Ltd.
5  *   for Toby Churchill Ltd and Brightstar Engineering
6  *
7  * Created by Charles Manning <charles@aleph1.co.uk>
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License version 2 as
11  * published by the Free Software Foundation.
12  */
13
14 const char *yaffs_guts_c_version =
15     "$Id: yaffs_guts.c,v 1.104 2010-01-05 22:58:15 charles Exp $";
16
17 #include "yportenv.h"
18
19 #include "yaffsinterface.h"
20 #include "yaffs_guts.h"
21 #include "yaffs_tagsvalidity.h"
22 #include "yaffs_getblockinfo.h"
23
24 #include "yaffs_tagscompat.h"
25 #ifndef CONFIG_YAFFS_USE_OWN_SORT
26 #include "yaffs_qsort.h"
27 #endif
28 #include "yaffs_nand.h"
29
30 #include "yaffs_checkptrw.h"
31
32 #include "yaffs_nand.h"
33 #include "yaffs_packedtags2.h"
34
35
36 #define YAFFS_PASSIVE_GC_CHUNKS 2
37
38 #include "yaffs_ecc.h"
39
40
41 /* Robustification (if it ever comes about...) */
42 static void yaffs_RetireBlock(yaffs_Device *dev, int blockInNAND);
43 static void yaffs_HandleWriteChunkError(yaffs_Device *dev, int chunkInNAND,
44                 int erasedOk);
45 static void yaffs_HandleWriteChunkOk(yaffs_Device *dev, int chunkInNAND,
46                                 const __u8 *data,
47                                 const yaffs_ExtendedTags *tags);
48 static void yaffs_HandleUpdateChunk(yaffs_Device *dev, int chunkInNAND,
49                                 const yaffs_ExtendedTags *tags);
50
51 /* Other local prototypes */
52 static void yaffs_UpdateParent(yaffs_Object *obj);
53 static int yaffs_UnlinkObject(yaffs_Object *obj);
54 static int yaffs_ObjectHasCachedWriteData(yaffs_Object *obj);
55
56 static void yaffs_HardlinkFixup(yaffs_Device *dev, yaffs_Object *hardList);
57
58 static int yaffs_WriteNewChunkWithTagsToNAND(yaffs_Device *dev,
59                                         const __u8 *buffer,
60                                         yaffs_ExtendedTags *tags,
61                                         int useReserve);
62 static int yaffs_PutChunkIntoFile(yaffs_Object *in, int chunkInInode,
63                                 int chunkInNAND, int inScan);
64
65 static yaffs_Object *yaffs_CreateNewObject(yaffs_Device *dev, int number,
66                                         yaffs_ObjectType type);
67 static void yaffs_AddObjectToDirectory(yaffs_Object *directory,
68                                 yaffs_Object *obj);
69 static int yaffs_UpdateObjectHeader(yaffs_Object *in, const YCHAR *name,
70                                 int force, int isShrink, int shadows);
71 static void yaffs_RemoveObjectFromDirectory(yaffs_Object *obj);
72 static int yaffs_CheckStructures(void);
73 static int yaffs_DeleteWorker(yaffs_Object *in, yaffs_Tnode *tn, __u32 level,
74                         int chunkOffset, int *limit);
75 static int yaffs_DoGenericObjectDeletion(yaffs_Object *in);
76
77 static yaffs_BlockInfo *yaffs_GetBlockInfo(yaffs_Device *dev, int blockNo);
78
79
80 static int yaffs_CheckChunkErased(struct yaffs_DeviceStruct *dev,
81                                 int chunkInNAND);
82
83 static int yaffs_UnlinkWorker(yaffs_Object *obj);
84
85 static int yaffs_TagsMatch(const yaffs_ExtendedTags *tags, int objectId,
86                         int chunkInObject);
87
88 static int yaffs_AllocateChunk(yaffs_Device *dev, int useReserve,
89                                 yaffs_BlockInfo **blockUsedPtr);
90
91 static void yaffs_VerifyFreeChunks(yaffs_Device *dev);
92
93 static void yaffs_CheckObjectDetailsLoaded(yaffs_Object *in);
94
95 static void yaffs_VerifyDirectory(yaffs_Object *directory);
96 #ifdef YAFFS_PARANOID
97 static int yaffs_CheckFileSanity(yaffs_Object *in);
98 #else
99 #define yaffs_CheckFileSanity(in)
100 #endif
101
102 static void yaffs_InvalidateWholeChunkCache(yaffs_Object *in);
103 static void yaffs_InvalidateChunkCache(yaffs_Object *object, int chunkId);
104
105 static void yaffs_InvalidateCheckpoint(yaffs_Device *dev);
106
107 static int yaffs_FindChunkInFile(yaffs_Object *in, int chunkInInode,
108                                 yaffs_ExtendedTags *tags);
109
110 static __u32 yaffs_GetChunkGroupBase(yaffs_Device *dev, yaffs_Tnode *tn,
111                 unsigned pos);
112 static yaffs_Tnode *yaffs_FindLevel0Tnode(yaffs_Device *dev,
113                                         yaffs_FileStructure *fStruct,
114                                         __u32 chunkId);
115
116 static void yaffs_SkipRestOfBlock(yaffs_Device *dev);
117 static int yaffs_VerifyChunkWritten(yaffs_Device *dev,
118                                         int chunkInNAND,
119                                         const __u8 *data,
120                                         yaffs_ExtendedTags *tags);
121
122 /* Function to calculate chunk and offset */
123
124 static void yaffs_AddrToChunk(yaffs_Device *dev, loff_t addr, int *chunkOut,
125                 __u32 *offsetOut)
126 {
127         int chunk;
128         __u32 offset;
129
130         chunk  = (__u32)(addr >> dev->chunkShift);
131
132         if (dev->chunkDiv == 1) {
133                 /* easy power of 2 case */
134                 offset = (__u32)(addr & dev->chunkMask);
135         } else {
136                 /* Non power-of-2 case */
137
138                 loff_t chunkBase;
139
140                 chunk /= dev->chunkDiv;
141
142                 chunkBase = ((loff_t)chunk) * dev->nDataBytesPerChunk;
143                 offset = (__u32)(addr - chunkBase);
144         }
145
146         *chunkOut = chunk;
147         *offsetOut = offset;
148 }
149
150 /* Function to return the number of shifts for a power of 2 greater than or
151  * equal to the given number
152  * Note we don't try to cater for all possible numbers and this does not have to
153  * be hellishly efficient.
154  */
155
156 static __u32 ShiftsGE(__u32 x)
157 {
158         int extraBits;
159         int nShifts;
160
161         nShifts = extraBits = 0;
162
163         while (x > 1) {
164                 if (x & 1)
165                         extraBits++;
166                 x >>= 1;
167                 nShifts++;
168         }
169
170         if (extraBits)
171                 nShifts++;
172
173         return nShifts;
174 }
175
176 /* Function to return the number of shifts to get a 1 in bit 0
177  */
178
179 static __u32 Shifts(__u32 x)
180 {
181         int nShifts;
182
183         nShifts =  0;
184
185         if (!x)
186                 return 0;
187
188         while (!(x&1)) {
189                 x >>= 1;
190                 nShifts++;
191         }
192
193         return nShifts;
194 }
195
196
197
198 /*
199  * Temporary buffer manipulations.
200  */
201
202 static int yaffs_InitialiseTempBuffers(yaffs_Device *dev)
203 {
204         int i;
205         __u8 *buf = (__u8 *)1;
206
207         memset(dev->tempBuffer, 0, sizeof(dev->tempBuffer));
208
209         for (i = 0; buf && i < YAFFS_N_TEMP_BUFFERS; i++) {
210                 dev->tempBuffer[i].line = 0;    /* not in use */
211                 dev->tempBuffer[i].buffer = buf =
212                     YMALLOC_DMA(dev->totalBytesPerChunk);
213         }
214
215         return buf ? YAFFS_OK : YAFFS_FAIL;
216 }
217
218 __u8 *yaffs_GetTempBuffer(yaffs_Device *dev, int lineNo)
219 {
220         int i, j;
221
222         dev->tempInUse++;
223         if (dev->tempInUse > dev->maxTemp)
224                 dev->maxTemp = dev->tempInUse;
225
226         for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
227                 if (dev->tempBuffer[i].line == 0) {
228                         dev->tempBuffer[i].line = lineNo;
229                         if ((i + 1) > dev->maxTemp) {
230                                 dev->maxTemp = i + 1;
231                                 for (j = 0; j <= i; j++)
232                                         dev->tempBuffer[j].maxLine =
233                                             dev->tempBuffer[j].line;
234                         }
235
236                         return dev->tempBuffer[i].buffer;
237                 }
238         }
239
240         T(YAFFS_TRACE_BUFFERS,
241           (TSTR("Out of temp buffers at line %d, other held by lines:"),
242            lineNo));
243         for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++)
244                 T(YAFFS_TRACE_BUFFERS, (TSTR(" %d "), dev->tempBuffer[i].line));
245
246         T(YAFFS_TRACE_BUFFERS, (TSTR(" " TENDSTR)));
247
248         /*
249          * If we got here then we have to allocate an unmanaged one
250          * This is not good.
251          */
252
253         dev->unmanagedTempAllocations++;
254         return YMALLOC(dev->nDataBytesPerChunk);
255
256 }
257
258 void yaffs_ReleaseTempBuffer(yaffs_Device *dev, __u8 *buffer,
259                                     int lineNo)
260 {
261         int i;
262
263         dev->tempInUse--;
264
265         for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
266                 if (dev->tempBuffer[i].buffer == buffer) {
267                         dev->tempBuffer[i].line = 0;
268                         return;
269                 }
270         }
271
272         if (buffer) {
273                 /* assume it is an unmanaged one. */
274                 T(YAFFS_TRACE_BUFFERS,
275                   (TSTR("Releasing unmanaged temp buffer in line %d" TENDSTR),
276                    lineNo));
277                 YFREE(buffer);
278                 dev->unmanagedTempDeallocations++;
279         }
280
281 }
282
283 /*
284  * Determine if we have a managed buffer.
285  */
286 int yaffs_IsManagedTempBuffer(yaffs_Device *dev, const __u8 *buffer)
287 {
288         int i;
289
290         for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
291                 if (dev->tempBuffer[i].buffer == buffer)
292                         return 1;
293         }
294
295         for (i = 0; i < dev->nShortOpCaches; i++) {
296                 if (dev->srCache[i].data == buffer)
297                         return 1;
298         }
299
300         if (buffer == dev->checkpointBuffer)
301                 return 1;
302
303         T(YAFFS_TRACE_ALWAYS,
304                 (TSTR("yaffs: unmaged buffer detected.\n" TENDSTR)));
305         return 0;
306 }
307
308
309
310 /*
311  * Chunk bitmap manipulations
312  */
313
314 static Y_INLINE __u8 *yaffs_BlockBits(yaffs_Device *dev, int blk)
315 {
316         if (blk < dev->internalStartBlock || blk > dev->internalEndBlock) {
317                 T(YAFFS_TRACE_ERROR,
318                         (TSTR("**>> yaffs: BlockBits block %d is not valid" TENDSTR),
319                         blk));
320                 YBUG();
321         }
322         return dev->chunkBits +
323                 (dev->chunkBitmapStride * (blk - dev->internalStartBlock));
324 }
325
326 static Y_INLINE void yaffs_VerifyChunkBitId(yaffs_Device *dev, int blk, int chunk)
327 {
328         if (blk < dev->internalStartBlock || blk > dev->internalEndBlock ||
329                         chunk < 0 || chunk >= dev->nChunksPerBlock) {
330                 T(YAFFS_TRACE_ERROR,
331                 (TSTR("**>> yaffs: Chunk Id (%d:%d) invalid"TENDSTR),
332                         blk, chunk));
333                 YBUG();
334         }
335 }
336
337 static Y_INLINE void yaffs_ClearChunkBits(yaffs_Device *dev, int blk)
338 {
339         __u8 *blkBits = yaffs_BlockBits(dev, blk);
340
341         memset(blkBits, 0, dev->chunkBitmapStride);
342 }
343
344 static Y_INLINE void yaffs_ClearChunkBit(yaffs_Device *dev, int blk, int chunk)
345 {
346         __u8 *blkBits = yaffs_BlockBits(dev, blk);
347
348         yaffs_VerifyChunkBitId(dev, blk, chunk);
349
350         blkBits[chunk / 8] &= ~(1 << (chunk & 7));
351 }
352
353 static Y_INLINE void yaffs_SetChunkBit(yaffs_Device *dev, int blk, int chunk)
354 {
355         __u8 *blkBits = yaffs_BlockBits(dev, blk);
356
357         yaffs_VerifyChunkBitId(dev, blk, chunk);
358
359         blkBits[chunk / 8] |= (1 << (chunk & 7));
360 }
361
362 static Y_INLINE int yaffs_CheckChunkBit(yaffs_Device *dev, int blk, int chunk)
363 {
364         __u8 *blkBits = yaffs_BlockBits(dev, blk);
365         yaffs_VerifyChunkBitId(dev, blk, chunk);
366
367         return (blkBits[chunk / 8] & (1 << (chunk & 7))) ? 1 : 0;
368 }
369
370 static Y_INLINE int yaffs_StillSomeChunkBits(yaffs_Device *dev, int blk)
371 {
372         __u8 *blkBits = yaffs_BlockBits(dev, blk);
373         int i;
374         for (i = 0; i < dev->chunkBitmapStride; i++) {
375                 if (*blkBits)
376                         return 1;
377                 blkBits++;
378         }
379         return 0;
380 }
381
382 static int yaffs_CountChunkBits(yaffs_Device *dev, int blk)
383 {
384         __u8 *blkBits = yaffs_BlockBits(dev, blk);
385         int i;
386         int n = 0;
387         for (i = 0; i < dev->chunkBitmapStride; i++) {
388                 __u8 x = *blkBits;
389                 while (x) {
390                         if (x & 1)
391                                 n++;
392                         x >>= 1;
393                 }
394
395                 blkBits++;
396         }
397         return n;
398 }
399
400 /*
401  * Verification code
402  */
403
404 static int yaffs_SkipVerification(yaffs_Device *dev)
405 {
406         return !(yaffs_traceMask & (YAFFS_TRACE_VERIFY | YAFFS_TRACE_VERIFY_FULL));
407 }
408
409 static int yaffs_SkipFullVerification(yaffs_Device *dev)
410 {
411         return !(yaffs_traceMask & (YAFFS_TRACE_VERIFY_FULL));
412 }
413
414 static int yaffs_SkipNANDVerification(yaffs_Device *dev)
415 {
416         return !(yaffs_traceMask & (YAFFS_TRACE_VERIFY_NAND));
417 }
418
419 static const char *blockStateName[] = {
420 "Unknown",
421 "Needs scanning",
422 "Scanning",
423 "Empty",
424 "Allocating",
425 "Full",
426 "Dirty",
427 "Checkpoint",
428 "Collecting",
429 "Dead"
430 };
431
432 static void yaffs_VerifyBlock(yaffs_Device *dev, yaffs_BlockInfo *bi, int n)
433 {
434         int actuallyUsed;
435         int inUse;
436
437         if (yaffs_SkipVerification(dev))
438                 return;
439
440         /* Report illegal runtime states */
441         if (bi->blockState >= YAFFS_NUMBER_OF_BLOCK_STATES)
442                 T(YAFFS_TRACE_VERIFY, (TSTR("Block %d has undefined state %d"TENDSTR), n, bi->blockState));
443
444         switch (bi->blockState) {
445         case YAFFS_BLOCK_STATE_UNKNOWN:
446         case YAFFS_BLOCK_STATE_SCANNING:
447         case YAFFS_BLOCK_STATE_NEEDS_SCANNING:
448                 T(YAFFS_TRACE_VERIFY, (TSTR("Block %d has bad run-state %s"TENDSTR),
449                 n, blockStateName[bi->blockState]));
450         }
451
452         /* Check pages in use and soft deletions are legal */
453
454         actuallyUsed = bi->pagesInUse - bi->softDeletions;
455
456         if (bi->pagesInUse < 0 || bi->pagesInUse > dev->nChunksPerBlock ||
457            bi->softDeletions < 0 || bi->softDeletions > dev->nChunksPerBlock ||
458            actuallyUsed < 0 || actuallyUsed > dev->nChunksPerBlock)
459                 T(YAFFS_TRACE_VERIFY, (TSTR("Block %d has illegal values pagesInUsed %d softDeletions %d"TENDSTR),
460                 n, bi->pagesInUse, bi->softDeletions));
461
462
463         /* Check chunk bitmap legal */
464         inUse = yaffs_CountChunkBits(dev, n);
465         if (inUse != bi->pagesInUse)
466                 T(YAFFS_TRACE_VERIFY, (TSTR("Block %d has inconsistent values pagesInUse %d counted chunk bits %d"TENDSTR),
467                         n, bi->pagesInUse, inUse));
468
469         /* Check that the sequence number is valid.
470          * Ten million is legal, but is very unlikely
471          */
472         if (dev->isYaffs2 &&
473            (bi->blockState == YAFFS_BLOCK_STATE_ALLOCATING || bi->blockState == YAFFS_BLOCK_STATE_FULL) &&
474            (bi->sequenceNumber < YAFFS_LOWEST_SEQUENCE_NUMBER || bi->sequenceNumber > 10000000))
475                 T(YAFFS_TRACE_VERIFY, (TSTR("Block %d has suspect sequence number of %d"TENDSTR),
476                 n, bi->sequenceNumber));
477 }
478
479 static void yaffs_VerifyCollectedBlock(yaffs_Device *dev, yaffs_BlockInfo *bi,
480                 int n)
481 {
482         yaffs_VerifyBlock(dev, bi, n);
483
484         /* After collection the block should be in the erased state */
485         /* This will need to change if we do partial gc */
486
487         if (bi->blockState != YAFFS_BLOCK_STATE_COLLECTING &&
488                         bi->blockState != YAFFS_BLOCK_STATE_EMPTY) {
489                 T(YAFFS_TRACE_ERROR, (TSTR("Block %d is in state %d after gc, should be erased"TENDSTR),
490                         n, bi->blockState));
491         }
492 }
493
494 static void yaffs_VerifyBlocks(yaffs_Device *dev)
495 {
496         int i;
497         int nBlocksPerState[YAFFS_NUMBER_OF_BLOCK_STATES];
498         int nIllegalBlockStates = 0;
499
500         if (yaffs_SkipVerification(dev))
501                 return;
502
503         memset(nBlocksPerState, 0, sizeof(nBlocksPerState));
504
505         for (i = dev->internalStartBlock; i <= dev->internalEndBlock; i++) {
506                 yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, i);
507                 yaffs_VerifyBlock(dev, bi, i);
508
509                 if (bi->blockState < YAFFS_NUMBER_OF_BLOCK_STATES)
510                         nBlocksPerState[bi->blockState]++;
511                 else
512                         nIllegalBlockStates++;
513         }
514
515         T(YAFFS_TRACE_VERIFY, (TSTR(""TENDSTR)));
516         T(YAFFS_TRACE_VERIFY, (TSTR("Block summary"TENDSTR)));
517
518         T(YAFFS_TRACE_VERIFY, (TSTR("%d blocks have illegal states"TENDSTR), nIllegalBlockStates));
519         if (nBlocksPerState[YAFFS_BLOCK_STATE_ALLOCATING] > 1)
520                 T(YAFFS_TRACE_VERIFY, (TSTR("Too many allocating blocks"TENDSTR)));
521
522         for (i = 0; i < YAFFS_NUMBER_OF_BLOCK_STATES; i++)
523                 T(YAFFS_TRACE_VERIFY,
524                   (TSTR("%s %d blocks"TENDSTR),
525                   blockStateName[i], nBlocksPerState[i]));
526
527         if (dev->blocksInCheckpoint != nBlocksPerState[YAFFS_BLOCK_STATE_CHECKPOINT])
528                 T(YAFFS_TRACE_VERIFY,
529                  (TSTR("Checkpoint block count wrong dev %d count %d"TENDSTR),
530                  dev->blocksInCheckpoint, nBlocksPerState[YAFFS_BLOCK_STATE_CHECKPOINT]));
531
532         if (dev->nErasedBlocks != nBlocksPerState[YAFFS_BLOCK_STATE_EMPTY])
533                 T(YAFFS_TRACE_VERIFY,
534                  (TSTR("Erased block count wrong dev %d count %d"TENDSTR),
535                  dev->nErasedBlocks, nBlocksPerState[YAFFS_BLOCK_STATE_EMPTY]));
536
537         if (nBlocksPerState[YAFFS_BLOCK_STATE_COLLECTING] > 1)
538                 T(YAFFS_TRACE_VERIFY,
539                  (TSTR("Too many collecting blocks %d (max is 1)"TENDSTR),
540                  nBlocksPerState[YAFFS_BLOCK_STATE_COLLECTING]));
541
542         T(YAFFS_TRACE_VERIFY, (TSTR(""TENDSTR)));
543
544 }
545
546 /*
547  * Verify the object header. oh must be valid, but obj and tags may be NULL in which
548  * case those tests will not be performed.
549  */
550 static void yaffs_VerifyObjectHeader(yaffs_Object *obj, yaffs_ObjectHeader *oh, yaffs_ExtendedTags *tags, int parentCheck)
551 {
552         if (obj && yaffs_SkipVerification(obj->myDev))
553                 return;
554
555         if (!(tags && obj && oh)) {
556                 T(YAFFS_TRACE_VERIFY,
557                                 (TSTR("Verifying object header tags %p obj %p oh %p"TENDSTR),
558                                 tags, obj, oh));
559                 return;
560         }
561
562         if (oh->type <= YAFFS_OBJECT_TYPE_UNKNOWN ||
563                         oh->type > YAFFS_OBJECT_TYPE_MAX)
564                 T(YAFFS_TRACE_VERIFY,
565                         (TSTR("Obj %d header type is illegal value 0x%x"TENDSTR),
566                         tags->objectId, oh->type));
567
568         if (tags->objectId != obj->objectId)
569                 T(YAFFS_TRACE_VERIFY,
570                         (TSTR("Obj %d header mismatch objectId %d"TENDSTR),
571                         tags->objectId, obj->objectId));
572
573
574         /*
575          * Check that the object's parent ids match if parentCheck requested.
576          *
577          * Tests do not apply to the root object.
578          */
579
580         if (parentCheck && tags->objectId > 1 && !obj->parent)
581                 T(YAFFS_TRACE_VERIFY,
582                         (TSTR("Obj %d header mismatch parentId %d obj->parent is NULL"TENDSTR),
583                         tags->objectId, oh->parentObjectId));
584
585         if (parentCheck && obj->parent &&
586                         oh->parentObjectId != obj->parent->objectId &&
587                         (oh->parentObjectId != YAFFS_OBJECTID_UNLINKED ||
588                         obj->parent->objectId != YAFFS_OBJECTID_DELETED))
589                 T(YAFFS_TRACE_VERIFY,
590                         (TSTR("Obj %d header mismatch parentId %d parentObjectId %d"TENDSTR),
591                         tags->objectId, oh->parentObjectId, obj->parent->objectId));
592
593         if (tags->objectId > 1 && oh->name[0] == 0) /* Null name */
594                 T(YAFFS_TRACE_VERIFY,
595                         (TSTR("Obj %d header name is NULL"TENDSTR),
596                         obj->objectId));
597
598         if (tags->objectId > 1 && ((__u8)(oh->name[0])) == 0xff) /* Trashed name */
599                 T(YAFFS_TRACE_VERIFY,
600                         (TSTR("Obj %d header name is 0xFF"TENDSTR),
601                         obj->objectId));
602 }
603
604
605
606 static int yaffs_VerifyTnodeWorker(yaffs_Object *obj, yaffs_Tnode *tn,
607                                         __u32 level, int chunkOffset)
608 {
609         int i;
610         yaffs_Device *dev = obj->myDev;
611         int ok = 1;
612
613         if (tn) {
614                 if (level > 0) {
615
616                         for (i = 0; i < YAFFS_NTNODES_INTERNAL && ok; i++) {
617                                 if (tn->internal[i]) {
618                                         ok = yaffs_VerifyTnodeWorker(obj,
619                                                         tn->internal[i],
620                                                         level - 1,
621                                                         (chunkOffset<<YAFFS_TNODES_INTERNAL_BITS) + i);
622                                 }
623                         }
624                 } else if (level == 0) {
625                         yaffs_ExtendedTags tags;
626                         __u32 objectId = obj->objectId;
627
628                         chunkOffset <<=  YAFFS_TNODES_LEVEL0_BITS;
629
630                         for (i = 0; i < YAFFS_NTNODES_LEVEL0; i++) {
631                                 __u32 theChunk = yaffs_GetChunkGroupBase(dev, tn, i);
632
633                                 if (theChunk > 0) {
634                                         /* T(~0,(TSTR("verifying (%d:%d) %d"TENDSTR),tags.objectId,tags.chunkId,theChunk)); */
635                                         yaffs_ReadChunkWithTagsFromNAND(dev, theChunk, NULL, &tags);
636                                         if (tags.objectId != objectId || tags.chunkId != chunkOffset) {
637                                                 T(~0, (TSTR("Object %d chunkId %d NAND mismatch chunk %d tags (%d:%d)"TENDSTR),
638                                                         objectId, chunkOffset, theChunk,
639                                                         tags.objectId, tags.chunkId));
640                                         }
641                                 }
642                                 chunkOffset++;
643                         }
644                 }
645         }
646
647         return ok;
648
649 }
650
651
652 static void yaffs_VerifyFile(yaffs_Object *obj)
653 {
654         int requiredTallness;
655         int actualTallness;
656         __u32 lastChunk;
657         __u32 x;
658         __u32 i;
659         yaffs_Device *dev;
660         yaffs_ExtendedTags tags;
661         yaffs_Tnode *tn;
662         __u32 objectId;
663
664         if (!obj)
665                 return;
666
667         if (yaffs_SkipVerification(obj->myDev))
668                 return;
669
670         dev = obj->myDev;
671         objectId = obj->objectId;
672
673         /* Check file size is consistent with tnode depth */
674         lastChunk =  obj->variant.fileVariant.fileSize / dev->nDataBytesPerChunk + 1;
675         x = lastChunk >> YAFFS_TNODES_LEVEL0_BITS;
676         requiredTallness = 0;
677         while (x > 0) {
678                 x >>= YAFFS_TNODES_INTERNAL_BITS;
679                 requiredTallness++;
680         }
681
682         actualTallness = obj->variant.fileVariant.topLevel;
683
684         if (requiredTallness > actualTallness)
685                 T(YAFFS_TRACE_VERIFY,
686                 (TSTR("Obj %d had tnode tallness %d, needs to be %d"TENDSTR),
687                  obj->objectId, actualTallness, requiredTallness));
688
689
690         /* Check that the chunks in the tnode tree are all correct.
691          * We do this by scanning through the tnode tree and
692          * checking the tags for every chunk match.
693          */
694
695         if (yaffs_SkipNANDVerification(dev))
696                 return;
697
698         for (i = 1; i <= lastChunk; i++) {
699                 tn = yaffs_FindLevel0Tnode(dev, &obj->variant.fileVariant, i);
700
701                 if (tn) {
702                         __u32 theChunk = yaffs_GetChunkGroupBase(dev, tn, i);
703                         if (theChunk > 0) {
704                                 /* T(~0,(TSTR("verifying (%d:%d) %d"TENDSTR),objectId,i,theChunk)); */
705                                 yaffs_ReadChunkWithTagsFromNAND(dev, theChunk, NULL, &tags);
706                                 if (tags.objectId != objectId || tags.chunkId != i) {
707                                         T(~0, (TSTR("Object %d chunkId %d NAND mismatch chunk %d tags (%d:%d)"TENDSTR),
708                                                 objectId, i, theChunk,
709                                                 tags.objectId, tags.chunkId));
710                                 }
711                         }
712                 }
713         }
714 }
715
716
717 static void yaffs_VerifyHardLink(yaffs_Object *obj)
718 {
719         if (obj && yaffs_SkipVerification(obj->myDev))
720                 return;
721
722         /* Verify sane equivalent object */
723 }
724
725 static void yaffs_VerifySymlink(yaffs_Object *obj)
726 {
727         if (obj && yaffs_SkipVerification(obj->myDev))
728                 return;
729
730         /* Verify symlink string */
731 }
732
733 static void yaffs_VerifySpecial(yaffs_Object *obj)
734 {
735         if (obj && yaffs_SkipVerification(obj->myDev))
736                 return;
737 }
738
739 static void yaffs_VerifyObject(yaffs_Object *obj)
740 {
741         yaffs_Device *dev;
742
743         __u32 chunkMin;
744         __u32 chunkMax;
745
746         __u32 chunkIdOk;
747         __u32 chunkInRange;
748         __u32 chunkShouldNotBeDeleted;
749         __u32 chunkValid;
750
751         if (!obj)
752                 return;
753
754         if (obj->beingCreated)
755                 return;
756
757         dev = obj->myDev;
758
759         if (yaffs_SkipVerification(dev))
760                 return;
761
762         /* Check sane object header chunk */
763
764         chunkMin = dev->internalStartBlock * dev->nChunksPerBlock;
765         chunkMax = (dev->internalEndBlock+1) * dev->nChunksPerBlock - 1;
766
767         chunkInRange = (((unsigned)(obj->hdrChunk)) >= chunkMin && ((unsigned)(obj->hdrChunk)) <= chunkMax);
768         chunkIdOk = chunkInRange || (obj->hdrChunk == 0);
769         chunkValid = chunkInRange &&
770                         yaffs_CheckChunkBit(dev,
771                                         obj->hdrChunk / dev->nChunksPerBlock,
772                                         obj->hdrChunk % dev->nChunksPerBlock);
773         chunkShouldNotBeDeleted = chunkInRange && !chunkValid;
774
775         if (!obj->fake &&
776                         (!chunkIdOk || chunkShouldNotBeDeleted)) {
777                 T(YAFFS_TRACE_VERIFY,
778                         (TSTR("Obj %d has chunkId %d %s %s"TENDSTR),
779                         obj->objectId, obj->hdrChunk,
780                         chunkIdOk ? "" : ",out of range",
781                         chunkShouldNotBeDeleted ? ",marked as deleted" : ""));
782         }
783
784         if (chunkValid && !yaffs_SkipNANDVerification(dev)) {
785                 yaffs_ExtendedTags tags;
786                 yaffs_ObjectHeader *oh;
787                 __u8 *buffer = yaffs_GetTempBuffer(dev, __LINE__);
788
789                 oh = (yaffs_ObjectHeader *)buffer;
790
791                 yaffs_ReadChunkWithTagsFromNAND(dev, obj->hdrChunk, buffer,
792                                 &tags);
793
794                 yaffs_VerifyObjectHeader(obj, oh, &tags, 1);
795
796                 yaffs_ReleaseTempBuffer(dev, buffer, __LINE__);
797         }
798
799         /* Verify it has a parent */
800         if (obj && !obj->fake &&
801                         (!obj->parent || obj->parent->myDev != dev)) {
802                 T(YAFFS_TRACE_VERIFY,
803                         (TSTR("Obj %d has parent pointer %p which does not look like an object"TENDSTR),
804                         obj->objectId, obj->parent));
805         }
806
807         /* Verify parent is a directory */
808         if (obj->parent && obj->parent->variantType != YAFFS_OBJECT_TYPE_DIRECTORY) {
809                 T(YAFFS_TRACE_VERIFY,
810                         (TSTR("Obj %d's parent is not a directory (type %d)"TENDSTR),
811                         obj->objectId, obj->parent->variantType));
812         }
813
814         switch (obj->variantType) {
815         case YAFFS_OBJECT_TYPE_FILE:
816                 yaffs_VerifyFile(obj);
817                 break;
818         case YAFFS_OBJECT_TYPE_SYMLINK:
819                 yaffs_VerifySymlink(obj);
820                 break;
821         case YAFFS_OBJECT_TYPE_DIRECTORY:
822                 yaffs_VerifyDirectory(obj);
823                 break;
824         case YAFFS_OBJECT_TYPE_HARDLINK:
825                 yaffs_VerifyHardLink(obj);
826                 break;
827         case YAFFS_OBJECT_TYPE_SPECIAL:
828                 yaffs_VerifySpecial(obj);
829                 break;
830         case YAFFS_OBJECT_TYPE_UNKNOWN:
831         default:
832                 T(YAFFS_TRACE_VERIFY,
833                 (TSTR("Obj %d has illegaltype %d"TENDSTR),
834                 obj->objectId, obj->variantType));
835                 break;
836         }
837 }
838
839 static void yaffs_VerifyObjects(yaffs_Device *dev)
840 {
841         yaffs_Object *obj;
842         int i;
843         struct ylist_head *lh;
844
845         if (yaffs_SkipVerification(dev))
846                 return;
847
848         /* Iterate through the objects in each hash entry */
849
850         for (i = 0; i <  YAFFS_NOBJECT_BUCKETS; i++) {
851                 ylist_for_each(lh, &dev->objectBucket[i].list) {
852                         if (lh) {
853                                 obj = ylist_entry(lh, yaffs_Object, hashLink);
854                                 yaffs_VerifyObject(obj);
855                         }
856                 }
857         }
858 }
859
860
861 /*
862  *  Simple hash function. Needs to have a reasonable spread
863  */
864
865 static Y_INLINE int yaffs_HashFunction(int n)
866 {
867         n = abs(n);
868         return n % YAFFS_NOBJECT_BUCKETS;
869 }
870
871 /*
872  * Access functions to useful fake objects.
873  * Note that root might have a presence in NAND if permissions are set.
874  */
875
876 yaffs_Object *yaffs_Root(yaffs_Device *dev)
877 {
878         return dev->rootDir;
879 }
880
881 yaffs_Object *yaffs_LostNFound(yaffs_Device *dev)
882 {
883         return dev->lostNFoundDir;
884 }
885
886
887 /*
888  *  Erased NAND checking functions
889  */
890
891 int yaffs_CheckFF(__u8 *buffer, int nBytes)
892 {
893         /* Horrible, slow implementation */
894         while (nBytes--) {
895                 if (*buffer != 0xFF)
896                         return 0;
897                 buffer++;
898         }
899         return 1;
900 }
901
902 static int yaffs_CheckChunkErased(struct yaffs_DeviceStruct *dev,
903                                 int chunkInNAND)
904 {
905         int retval = YAFFS_OK;
906         __u8 *data = yaffs_GetTempBuffer(dev, __LINE__);
907         yaffs_ExtendedTags tags;
908         int result;
909
910         result = yaffs_ReadChunkWithTagsFromNAND(dev, chunkInNAND, data, &tags);
911
912         if (tags.eccResult > YAFFS_ECC_RESULT_NO_ERROR)
913                 retval = YAFFS_FAIL;
914
915         if (!yaffs_CheckFF(data, dev->nDataBytesPerChunk) || tags.chunkUsed) {
916                 T(YAFFS_TRACE_NANDACCESS,
917                   (TSTR("Chunk %d not erased" TENDSTR), chunkInNAND));
918                 retval = YAFFS_FAIL;
919         }
920
921         yaffs_ReleaseTempBuffer(dev, data, __LINE__);
922
923         return retval;
924
925 }
926
927
928 static int yaffs_VerifyChunkWritten(yaffs_Device *dev,
929                                         int chunkInNAND,
930                                         const __u8 *data,
931                                         yaffs_ExtendedTags *tags)
932 {
933         int retval = YAFFS_OK;
934         yaffs_ExtendedTags tempTags;
935         __u8 *buffer = yaffs_GetTempBuffer(dev,__LINE__);
936         int result;
937         
938         result = yaffs_ReadChunkWithTagsFromNAND(dev,chunkInNAND,buffer,&tempTags);
939         if(memcmp(buffer,data,dev->nDataBytesPerChunk) ||
940                 tempTags.objectId != tags->objectId ||
941                 tempTags.chunkId  != tags->chunkId ||
942                 tempTags.byteCount != tags->byteCount)
943                 retval = YAFFS_FAIL;
944
945         yaffs_ReleaseTempBuffer(dev, buffer, __LINE__);
946
947         return retval;
948 }
949
950 static int yaffs_WriteNewChunkWithTagsToNAND(struct yaffs_DeviceStruct *dev,
951                                         const __u8 *data,
952                                         yaffs_ExtendedTags *tags,
953                                         int useReserve)
954 {
955         int attempts = 0;
956         int writeOk = 0;
957         int chunk;
958
959         yaffs_InvalidateCheckpoint(dev);
960
961         do {
962                 yaffs_BlockInfo *bi = 0;
963                 int erasedOk = 0;
964
965                 chunk = yaffs_AllocateChunk(dev, useReserve, &bi);
966                 if (chunk < 0) {
967                         /* no space */
968                         break;
969                 }
970
971                 /* First check this chunk is erased, if it needs
972                  * checking.  The checking policy (unless forced
973                  * always on) is as follows:
974                  *
975                  * Check the first page we try to write in a block.
976                  * If the check passes then we don't need to check any
977                  * more.        If the check fails, we check again...
978                  * If the block has been erased, we don't need to check.
979                  *
980                  * However, if the block has been prioritised for gc,
981                  * then we think there might be something odd about
982                  * this block and stop using it.
983                  *
984                  * Rationale: We should only ever see chunks that have
985                  * not been erased if there was a partially written
986                  * chunk due to power loss.  This checking policy should
987                  * catch that case with very few checks and thus save a
988                  * lot of checks that are most likely not needed.
989                  *
990                  * Mods to the above
991                  * If an erase check fails or the write fails we skip the 
992                  * rest of the block.
993                  */
994
995                 /* let's give it a try */
996                 attempts++;
997
998 #ifdef CONFIG_YAFFS_ALWAYS_CHECK_CHUNK_ERASED
999                 bi->skipErasedCheck = 0;
1000 #endif
1001                 if (!bi->skipErasedCheck) {
1002                         erasedOk = yaffs_CheckChunkErased(dev, chunk);
1003                         if (erasedOk != YAFFS_OK) {
1004                                 T(YAFFS_TRACE_ERROR,
1005                                 (TSTR("**>> yaffs chunk %d was not erased"
1006                                 TENDSTR), chunk));
1007
1008                                 /* If not erased, delete this one,
1009                                  * skip rest of block and
1010                                  * try another chunk */
1011                                  yaffs_DeleteChunk(dev,chunk,1,__LINE__);
1012                                  yaffs_SkipRestOfBlock(dev);
1013                                 continue;
1014                         }
1015                 }
1016
1017                 writeOk = yaffs_WriteChunkWithTagsToNAND(dev, chunk,
1018                                 data, tags);
1019
1020                 if(!bi->skipErasedCheck)
1021                         writeOk = yaffs_VerifyChunkWritten(dev, chunk, data, tags);
1022
1023                 if (writeOk != YAFFS_OK) {
1024                         /* Clean up aborted write, skip to next block and
1025                          * try another chunk */
1026                         yaffs_HandleWriteChunkError(dev, chunk, erasedOk);
1027                         continue;
1028                 }
1029
1030                 bi->skipErasedCheck = 1;
1031
1032                 /* Copy the data into the robustification buffer */
1033                 yaffs_HandleWriteChunkOk(dev, chunk, data, tags);
1034
1035         } while (writeOk != YAFFS_OK &&
1036                 (yaffs_wr_attempts <= 0 || attempts <= yaffs_wr_attempts));
1037
1038         if (!writeOk)
1039                 chunk = -1;
1040
1041         if (attempts > 1) {
1042                 T(YAFFS_TRACE_ERROR,
1043                         (TSTR("**>> yaffs write required %d attempts" TENDSTR),
1044                         attempts));
1045
1046                 dev->nRetriedWrites += (attempts - 1);
1047         }
1048
1049         return chunk;
1050 }
1051
1052 /*
1053  * Block retiring for handling a broken block.
1054  */
1055
1056 static void yaffs_RetireBlock(yaffs_Device *dev, int blockInNAND)
1057 {
1058         yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, blockInNAND);
1059
1060         yaffs_InvalidateCheckpoint(dev);
1061
1062         if (yaffs_MarkBlockBad(dev, blockInNAND) != YAFFS_OK) {
1063                 if (yaffs_EraseBlockInNAND(dev, blockInNAND) != YAFFS_OK) {
1064                         T(YAFFS_TRACE_ALWAYS, (TSTR(
1065                                 "yaffs: Failed to mark bad and erase block %d"
1066                                 TENDSTR), blockInNAND));
1067                 } else {
1068                         yaffs_ExtendedTags tags;
1069                         int chunkId = blockInNAND * dev->nChunksPerBlock;
1070
1071                         __u8 *buffer = yaffs_GetTempBuffer(dev, __LINE__);
1072
1073                         memset(buffer, 0xff, dev->nDataBytesPerChunk);
1074                         yaffs_InitialiseTags(&tags);
1075                         tags.sequenceNumber = YAFFS_SEQUENCE_BAD_BLOCK;
1076                         if (dev->writeChunkWithTagsToNAND(dev, chunkId -
1077                                 dev->chunkOffset, buffer, &tags) != YAFFS_OK)
1078                                 T(YAFFS_TRACE_ALWAYS, (TSTR("yaffs: Failed to "
1079                                         TCONT("write bad block marker to block %d")
1080                                         TENDSTR), blockInNAND));
1081
1082                         yaffs_ReleaseTempBuffer(dev, buffer, __LINE__);
1083                 }
1084         }
1085
1086         bi->blockState = YAFFS_BLOCK_STATE_DEAD;
1087         bi->gcPrioritise = 0;
1088         bi->needsRetiring = 0;
1089
1090         dev->nRetiredBlocks++;
1091 }
1092
1093 /*
1094  * Functions for robustisizing TODO
1095  *
1096  */
1097
1098 static void yaffs_HandleWriteChunkOk(yaffs_Device *dev, int chunkInNAND,
1099                                 const __u8 *data,
1100                                 const yaffs_ExtendedTags *tags)
1101 {
1102 }
1103
1104 static void yaffs_HandleUpdateChunk(yaffs_Device *dev, int chunkInNAND,
1105                                 const yaffs_ExtendedTags *tags)
1106 {
1107 }
1108
1109 void yaffs_HandleChunkError(yaffs_Device *dev, yaffs_BlockInfo *bi)
1110 {
1111         if (!bi->gcPrioritise) {
1112                 bi->gcPrioritise = 1;
1113                 dev->hasPendingPrioritisedGCs = 1;
1114                 bi->chunkErrorStrikes++;
1115
1116                 if (bi->chunkErrorStrikes > 3) {
1117                         bi->needsRetiring = 1; /* Too many stikes, so retire this */
1118                         T(YAFFS_TRACE_ALWAYS, (TSTR("yaffs: Block struck out" TENDSTR)));
1119
1120                 }
1121         }
1122 }
1123
1124 static void yaffs_HandleWriteChunkError(yaffs_Device *dev, int chunkInNAND,
1125                 int erasedOk)
1126 {
1127         int blockInNAND = chunkInNAND / dev->nChunksPerBlock;
1128         yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, blockInNAND);
1129
1130         yaffs_HandleChunkError(dev, bi);
1131
1132         if (erasedOk) {
1133                 /* Was an actual write failure, so mark the block for retirement  */
1134                 bi->needsRetiring = 1;
1135                 T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
1136                   (TSTR("**>> Block %d needs retiring" TENDSTR), blockInNAND));
1137         }
1138
1139         /* Delete the chunk */
1140         yaffs_DeleteChunk(dev, chunkInNAND, 1, __LINE__);
1141         yaffs_SkipRestOfBlock(dev);
1142 }
1143
1144
1145 /*---------------- Name handling functions ------------*/
1146
1147 static __u16 yaffs_CalcNameSum(const YCHAR *name)
1148 {
1149         __u16 sum = 0;
1150         __u16 i = 1;
1151
1152         const YUCHAR *bname = (const YUCHAR *) name;
1153         if (bname) {
1154                 while ((*bname) && (i < (YAFFS_MAX_NAME_LENGTH/2))) {
1155
1156 #ifdef CONFIG_YAFFS_CASE_INSENSITIVE
1157                         sum += yaffs_toupper(*bname) * i;
1158 #else
1159                         sum += (*bname) * i;
1160 #endif
1161                         i++;
1162                         bname++;
1163                 }
1164         }
1165         return sum;
1166 }
1167
1168 static void yaffs_SetObjectName(yaffs_Object *obj, const YCHAR *name)
1169 {
1170 #ifdef CONFIG_YAFFS_SHORT_NAMES_IN_RAM
1171         memset(obj->shortName, 0, sizeof(YCHAR) * (YAFFS_SHORT_NAME_LENGTH+1));
1172         if (name && yaffs_strnlen(name,YAFFS_SHORT_NAME_LENGTH+1) <= YAFFS_SHORT_NAME_LENGTH)
1173                 yaffs_strcpy(obj->shortName, name);
1174         else
1175                 obj->shortName[0] = _Y('\0');
1176 #endif
1177         obj->sum = yaffs_CalcNameSum(name);
1178 }
1179
1180 /*-------------------- TNODES -------------------
1181
1182  * List of spare tnodes
1183  * The list is hooked together using the first pointer
1184  * in the tnode.
1185  */
1186
1187 /* yaffs_CreateTnodes creates a bunch more tnodes and
1188  * adds them to the tnode free list.
1189  * Don't use this function directly
1190  */
1191
1192 static int yaffs_CreateTnodes(yaffs_Device *dev, int nTnodes)
1193 {
1194         int i;
1195         int tnodeSize;
1196         yaffs_Tnode *newTnodes;
1197         __u8 *mem;
1198         yaffs_Tnode *curr;
1199         yaffs_Tnode *next;
1200         yaffs_TnodeList *tnl;
1201
1202         if (nTnodes < 1)
1203                 return YAFFS_OK;
1204
1205         /* Calculate the tnode size in bytes for variable width tnode support.
1206          * Must be a multiple of 32-bits  */
1207         tnodeSize = (dev->tnodeWidth * YAFFS_NTNODES_LEVEL0)/8;
1208
1209         if (tnodeSize < sizeof(yaffs_Tnode))
1210                 tnodeSize = sizeof(yaffs_Tnode);
1211
1212         /* make these things */
1213
1214         newTnodes = YMALLOC(nTnodes * tnodeSize);
1215         mem = (__u8 *)newTnodes;
1216
1217         if (!newTnodes) {
1218                 T(YAFFS_TRACE_ERROR,
1219                         (TSTR("yaffs: Could not allocate Tnodes" TENDSTR)));
1220                 return YAFFS_FAIL;
1221         }
1222
1223         /* Hook them into the free list */
1224 #if 0
1225         for (i = 0; i < nTnodes - 1; i++) {
1226                 newTnodes[i].internal[0] = &newTnodes[i + 1];
1227 #ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
1228                 newTnodes[i].internal[YAFFS_NTNODES_INTERNAL] = (void *)1;
1229 #endif
1230         }
1231
1232         newTnodes[nTnodes - 1].internal[0] = dev->freeTnodes;
1233 #ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
1234         newTnodes[nTnodes - 1].internal[YAFFS_NTNODES_INTERNAL] = (void *)1;
1235 #endif
1236         dev->freeTnodes = newTnodes;
1237 #else
1238         /* New hookup for wide tnodes */
1239         for (i = 0; i < nTnodes - 1; i++) {
1240                 curr = (yaffs_Tnode *) &mem[i * tnodeSize];
1241                 next = (yaffs_Tnode *) &mem[(i+1) * tnodeSize];
1242                 curr->internal[0] = next;
1243         }
1244
1245         curr = (yaffs_Tnode *) &mem[(nTnodes - 1) * tnodeSize];
1246         curr->internal[0] = dev->freeTnodes;
1247         dev->freeTnodes = (yaffs_Tnode *)mem;
1248
1249 #endif
1250
1251
1252         dev->nFreeTnodes += nTnodes;
1253         dev->nTnodesCreated += nTnodes;
1254
1255         /* Now add this bunch of tnodes to a list for freeing up.
1256          * NB If we can't add this to the management list it isn't fatal
1257          * but it just means we can't free this bunch of tnodes later.
1258          */
1259
1260         tnl = YMALLOC(sizeof(yaffs_TnodeList));
1261         if (!tnl) {
1262                 T(YAFFS_TRACE_ERROR,
1263                   (TSTR
1264                    ("yaffs: Could not add tnodes to management list" TENDSTR)));
1265                    return YAFFS_FAIL;
1266         } else {
1267                 tnl->tnodes = newTnodes;
1268                 tnl->next = dev->allocatedTnodeList;
1269                 dev->allocatedTnodeList = tnl;
1270         }
1271
1272         T(YAFFS_TRACE_ALLOCATE, (TSTR("yaffs: Tnodes added" TENDSTR)));
1273
1274         return YAFFS_OK;
1275 }
1276
1277 /* GetTnode gets us a clean tnode. Tries to make allocate more if we run out */
1278
1279 static yaffs_Tnode *yaffs_GetTnodeRaw(yaffs_Device *dev)
1280 {
1281         yaffs_Tnode *tn = NULL;
1282
1283         /* If there are none left make more */
1284         if (!dev->freeTnodes)
1285                 yaffs_CreateTnodes(dev, YAFFS_ALLOCATION_NTNODES);
1286
1287         if (dev->freeTnodes) {
1288                 tn = dev->freeTnodes;
1289 #ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
1290                 if (tn->internal[YAFFS_NTNODES_INTERNAL] != (void *)1) {
1291                         /* Hoosterman, this thing looks like it isn't in the list */
1292                         T(YAFFS_TRACE_ALWAYS,
1293                           (TSTR("yaffs: Tnode list bug 1" TENDSTR)));
1294                 }
1295 #endif
1296                 dev->freeTnodes = dev->freeTnodes->internal[0];
1297                 dev->nFreeTnodes--;
1298         }
1299
1300         dev->nCheckpointBlocksRequired = 0; /* force recalculation*/
1301
1302         return tn;
1303 }
1304
1305 static yaffs_Tnode *yaffs_GetTnode(yaffs_Device *dev)
1306 {
1307         yaffs_Tnode *tn = yaffs_GetTnodeRaw(dev);
1308         int tnodeSize = (dev->tnodeWidth * YAFFS_NTNODES_LEVEL0)/8;
1309
1310         if (tnodeSize < sizeof(yaffs_Tnode))
1311                 tnodeSize = sizeof(yaffs_Tnode);
1312
1313         if (tn)
1314                 memset(tn, 0, tnodeSize);
1315
1316         return tn;
1317 }
1318
1319 /* FreeTnode frees up a tnode and puts it back on the free list */
1320 static void yaffs_FreeTnode(yaffs_Device *dev, yaffs_Tnode *tn)
1321 {
1322         if (tn) {
1323 #ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
1324                 if (tn->internal[YAFFS_NTNODES_INTERNAL] != 0) {
1325                         /* Hoosterman, this thing looks like it is already in the list */
1326                         T(YAFFS_TRACE_ALWAYS,
1327                           (TSTR("yaffs: Tnode list bug 2" TENDSTR)));
1328                 }
1329                 tn->internal[YAFFS_NTNODES_INTERNAL] = (void *)1;
1330 #endif
1331                 tn->internal[0] = dev->freeTnodes;
1332                 dev->freeTnodes = tn;
1333                 dev->nFreeTnodes++;
1334         }
1335         dev->nCheckpointBlocksRequired = 0; /* force recalculation*/
1336 }
1337
1338 static void yaffs_DeinitialiseTnodes(yaffs_Device *dev)
1339 {
1340         /* Free the list of allocated tnodes */
1341         yaffs_TnodeList *tmp;
1342
1343         while (dev->allocatedTnodeList) {
1344                 tmp = dev->allocatedTnodeList->next;
1345
1346                 YFREE(dev->allocatedTnodeList->tnodes);
1347                 YFREE(dev->allocatedTnodeList);
1348                 dev->allocatedTnodeList = tmp;
1349
1350         }
1351
1352         dev->freeTnodes = NULL;
1353         dev->nFreeTnodes = 0;
1354         dev->nTnodesCreated = 0;
1355 }
1356
1357 static void yaffs_InitialiseTnodes(yaffs_Device *dev)
1358 {
1359         dev->allocatedTnodeList = NULL;
1360         dev->freeTnodes = NULL;
1361         dev->nFreeTnodes = 0;
1362         dev->nTnodesCreated = 0;
1363 }
1364
1365
1366 void yaffs_LoadLevel0Tnode(yaffs_Device *dev, yaffs_Tnode *tn, unsigned pos,
1367                 unsigned val)
1368 {
1369         __u32 *map = (__u32 *)tn;
1370         __u32 bitInMap;
1371         __u32 bitInWord;
1372         __u32 wordInMap;
1373         __u32 mask;
1374
1375         pos &= YAFFS_TNODES_LEVEL0_MASK;
1376         val >>= dev->chunkGroupBits;
1377
1378         bitInMap = pos * dev->tnodeWidth;
1379         wordInMap = bitInMap / 32;
1380         bitInWord = bitInMap & (32 - 1);
1381
1382         mask = dev->tnodeMask << bitInWord;
1383
1384         map[wordInMap] &= ~mask;
1385         map[wordInMap] |= (mask & (val << bitInWord));
1386
1387         if (dev->tnodeWidth > (32 - bitInWord)) {
1388                 bitInWord = (32 - bitInWord);
1389                 wordInMap++;;
1390                 mask = dev->tnodeMask >> (/*dev->tnodeWidth -*/ bitInWord);
1391                 map[wordInMap] &= ~mask;
1392                 map[wordInMap] |= (mask & (val >> bitInWord));
1393         }
1394 }
1395
1396 static __u32 yaffs_GetChunkGroupBase(yaffs_Device *dev, yaffs_Tnode *tn,
1397                 unsigned pos)
1398 {
1399         __u32 *map = (__u32 *)tn;
1400         __u32 bitInMap;
1401         __u32 bitInWord;
1402         __u32 wordInMap;
1403         __u32 val;
1404
1405         pos &= YAFFS_TNODES_LEVEL0_MASK;
1406
1407         bitInMap = pos * dev->tnodeWidth;
1408         wordInMap = bitInMap / 32;
1409         bitInWord = bitInMap & (32 - 1);
1410
1411         val = map[wordInMap] >> bitInWord;
1412
1413         if      (dev->tnodeWidth > (32 - bitInWord)) {
1414                 bitInWord = (32 - bitInWord);
1415                 wordInMap++;;
1416                 val |= (map[wordInMap] << bitInWord);
1417         }
1418
1419         val &= dev->tnodeMask;
1420         val <<= dev->chunkGroupBits;
1421
1422         return val;
1423 }
1424
1425 /* ------------------- End of individual tnode manipulation -----------------*/
1426
1427 /* ---------Functions to manipulate the look-up tree (made up of tnodes) ------
1428  * The look up tree is represented by the top tnode and the number of topLevel
1429  * in the tree. 0 means only the level 0 tnode is in the tree.
1430  */
1431
1432 /* FindLevel0Tnode finds the level 0 tnode, if one exists. */
1433 static yaffs_Tnode *yaffs_FindLevel0Tnode(yaffs_Device *dev,
1434                                         yaffs_FileStructure *fStruct,
1435                                         __u32 chunkId)
1436 {
1437         yaffs_Tnode *tn = fStruct->top;
1438         __u32 i;
1439         int requiredTallness;
1440         int level = fStruct->topLevel;
1441
1442         /* Check sane level and chunk Id */
1443         if (level < 0 || level > YAFFS_TNODES_MAX_LEVEL)
1444                 return NULL;
1445
1446         if (chunkId > YAFFS_MAX_CHUNK_ID)
1447                 return NULL;
1448
1449         /* First check we're tall enough (ie enough topLevel) */
1450
1451         i = chunkId >> YAFFS_TNODES_LEVEL0_BITS;
1452         requiredTallness = 0;
1453         while (i) {
1454                 i >>= YAFFS_TNODES_INTERNAL_BITS;
1455                 requiredTallness++;
1456         }
1457
1458         if (requiredTallness > fStruct->topLevel)
1459                 return NULL; /* Not tall enough, so we can't find it */
1460
1461         /* Traverse down to level 0 */
1462         while (level > 0 && tn) {
1463                 tn = tn->internal[(chunkId >>
1464                         (YAFFS_TNODES_LEVEL0_BITS +
1465                                 (level - 1) *
1466                                 YAFFS_TNODES_INTERNAL_BITS)) &
1467                         YAFFS_TNODES_INTERNAL_MASK];
1468                 level--;
1469         }
1470
1471         return tn;
1472 }
1473
1474 /* AddOrFindLevel0Tnode finds the level 0 tnode if it exists, otherwise first expands the tree.
1475  * This happens in two steps:
1476  *  1. If the tree isn't tall enough, then make it taller.
1477  *  2. Scan down the tree towards the level 0 tnode adding tnodes if required.
1478  *
1479  * Used when modifying the tree.
1480  *
1481  *  If the tn argument is NULL, then a fresh tnode will be added otherwise the specified tn will
1482  *  be plugged into the ttree.
1483  */
1484
1485 static yaffs_Tnode *yaffs_AddOrFindLevel0Tnode(yaffs_Device *dev,
1486                                         yaffs_FileStructure *fStruct,
1487                                         __u32 chunkId,
1488                                         yaffs_Tnode *passedTn)
1489 {
1490         int requiredTallness;
1491         int i;
1492         int l;
1493         yaffs_Tnode *tn;
1494
1495         __u32 x;
1496
1497
1498         /* Check sane level and page Id */
1499         if (fStruct->topLevel < 0 || fStruct->topLevel > YAFFS_TNODES_MAX_LEVEL)
1500                 return NULL;
1501
1502         if (chunkId > YAFFS_MAX_CHUNK_ID)
1503                 return NULL;
1504
1505         /* First check we're tall enough (ie enough topLevel) */
1506
1507         x = chunkId >> YAFFS_TNODES_LEVEL0_BITS;
1508         requiredTallness = 0;
1509         while (x) {
1510                 x >>= YAFFS_TNODES_INTERNAL_BITS;
1511                 requiredTallness++;
1512         }
1513
1514
1515         if (requiredTallness > fStruct->topLevel) {
1516                 /* Not tall enough, gotta make the tree taller */
1517                 for (i = fStruct->topLevel; i < requiredTallness; i++) {
1518
1519                         tn = yaffs_GetTnode(dev);
1520
1521                         if (tn) {
1522                                 tn->internal[0] = fStruct->top;
1523                                 fStruct->top = tn;
1524                                 fStruct->topLevel++;
1525                         } else {
1526                                 T(YAFFS_TRACE_ERROR,
1527                                         (TSTR("yaffs: no more tnodes" TENDSTR)));
1528                                 return NULL;
1529                         }
1530                 }
1531         }
1532
1533         /* Traverse down to level 0, adding anything we need */
1534
1535         l = fStruct->topLevel;
1536         tn = fStruct->top;
1537
1538         if (l > 0) {
1539                 while (l > 0 && tn) {
1540                         x = (chunkId >>
1541                              (YAFFS_TNODES_LEVEL0_BITS +
1542                               (l - 1) * YAFFS_TNODES_INTERNAL_BITS)) &
1543                             YAFFS_TNODES_INTERNAL_MASK;
1544
1545
1546                         if ((l > 1) && !tn->internal[x]) {
1547                                 /* Add missing non-level-zero tnode */
1548                                 tn->internal[x] = yaffs_GetTnode(dev);
1549                                 if(!tn->internal[x])
1550                                         return NULL;
1551
1552                         } else if (l == 1) {
1553                                 /* Looking from level 1 at level 0 */
1554                                 if (passedTn) {
1555                                         /* If we already have one, then release it.*/
1556                                         if (tn->internal[x])
1557                                                 yaffs_FreeTnode(dev, tn->internal[x]);
1558                                         tn->internal[x] = passedTn;
1559
1560                                 } else if (!tn->internal[x]) {
1561                                         /* Don't have one, none passed in */
1562                                         tn->internal[x] = yaffs_GetTnode(dev);
1563                                         if(!tn->internal[x])
1564                                                 return NULL;
1565                                 }
1566                         }
1567
1568                         tn = tn->internal[x];
1569                         l--;
1570                 }
1571         } else {
1572                 /* top is level 0 */
1573                 if (passedTn) {
1574                         memcpy(tn, passedTn, (dev->tnodeWidth * YAFFS_NTNODES_LEVEL0)/8);
1575                         yaffs_FreeTnode(dev, passedTn);
1576                 }
1577         }
1578
1579         return tn;
1580 }
1581
1582 static int yaffs_FindChunkInGroup(yaffs_Device *dev, int theChunk,
1583                                 yaffs_ExtendedTags *tags, int objectId,
1584                                 int chunkInInode)
1585 {
1586         int j;
1587
1588         for (j = 0; theChunk && j < dev->chunkGroupSize; j++) {
1589                 if (yaffs_CheckChunkBit(dev, theChunk / dev->nChunksPerBlock,
1590                                 theChunk % dev->nChunksPerBlock)) {
1591                         
1592                         if(dev->chunkGroupSize == 1)
1593                                 return theChunk;
1594                         else {
1595                                 yaffs_ReadChunkWithTagsFromNAND(dev, theChunk, NULL,
1596                                                                 tags);
1597                                 if (yaffs_TagsMatch(tags, objectId, chunkInInode)) {
1598                                         /* found it; */
1599                                         return theChunk;
1600                                 }
1601                         }
1602                 }
1603                 theChunk++;
1604         }
1605         return -1;
1606 }
1607
1608
1609 /* DeleteWorker scans backwards through the tnode tree and deletes all the
1610  * chunks and tnodes in the file
1611  * Returns 1 if the tree was deleted.
1612  * Returns 0 if it stopped early due to hitting the limit and the delete is incomplete.
1613  */
1614
1615 static int yaffs_DeleteWorker(yaffs_Object *in, yaffs_Tnode *tn, __u32 level,
1616                               int chunkOffset, int *limit)
1617 {
1618         int i;
1619         int chunkInInode;
1620         int theChunk;
1621         yaffs_ExtendedTags tags;
1622         int foundChunk;
1623         yaffs_Device *dev = in->myDev;
1624
1625         int allDone = 1;
1626
1627         if (tn) {
1628                 if (level > 0) {
1629                         for (i = YAFFS_NTNODES_INTERNAL - 1; allDone && i >= 0;
1630                              i--) {
1631                                 if (tn->internal[i]) {
1632                                         if (limit && (*limit) < 0) {
1633                                                 allDone = 0;
1634                                         } else {
1635                                                 allDone =
1636                                                         yaffs_DeleteWorker(in,
1637                                                                 tn->
1638                                                                 internal
1639                                                                 [i],
1640                                                                 level -
1641                                                                 1,
1642                                                                 (chunkOffset
1643                                                                         <<
1644                                                                         YAFFS_TNODES_INTERNAL_BITS)
1645                                                                 + i,
1646                                                                 limit);
1647                                         }
1648                                         if (allDone) {
1649                                                 yaffs_FreeTnode(dev,
1650                                                                 tn->
1651                                                                 internal[i]);
1652                                                 tn->internal[i] = NULL;
1653                                         }
1654                                 }
1655                         }
1656                         return (allDone) ? 1 : 0;
1657                 } else if (level == 0) {
1658                         int hitLimit = 0;
1659
1660                         for (i = YAFFS_NTNODES_LEVEL0 - 1; i >= 0 && !hitLimit;
1661                                         i--) {
1662                                 theChunk = yaffs_GetChunkGroupBase(dev, tn, i);
1663                                 if (theChunk) {
1664
1665                                         chunkInInode = (chunkOffset <<
1666                                                 YAFFS_TNODES_LEVEL0_BITS) + i;
1667
1668                                         foundChunk =
1669                                                 yaffs_FindChunkInGroup(dev,
1670                                                                 theChunk,
1671                                                                 &tags,
1672                                                                 in->objectId,
1673                                                                 chunkInInode);
1674
1675                                         if (foundChunk > 0) {
1676                                                 yaffs_DeleteChunk(dev,
1677                                                                   foundChunk, 1,
1678                                                                   __LINE__);
1679                                                 in->nDataChunks--;
1680                                                 if (limit) {
1681                                                         *limit = *limit - 1;
1682                                                         if (*limit <= 0)
1683                                                                 hitLimit = 1;
1684                                                 }
1685
1686                                         }
1687
1688                                         yaffs_LoadLevel0Tnode(dev, tn, i, 0);
1689                                 }
1690
1691                         }
1692                         return (i < 0) ? 1 : 0;
1693
1694                 }
1695
1696         }
1697
1698         return 1;
1699
1700 }
1701
1702 static void yaffs_SoftDeleteChunk(yaffs_Device *dev, int chunk)
1703 {
1704         yaffs_BlockInfo *theBlock;
1705
1706         T(YAFFS_TRACE_DELETION, (TSTR("soft delete chunk %d" TENDSTR), chunk));
1707
1708         theBlock = yaffs_GetBlockInfo(dev, chunk / dev->nChunksPerBlock);
1709         if (theBlock) {
1710                 theBlock->softDeletions++;
1711                 dev->nFreeChunks++;
1712         }
1713 }
1714
1715 /* SoftDeleteWorker scans backwards through the tnode tree and soft deletes all the chunks in the file.
1716  * All soft deleting does is increment the block's softdelete count and pulls the chunk out
1717  * of the tnode.
1718  * Thus, essentially this is the same as DeleteWorker except that the chunks are soft deleted.
1719  */
1720
1721 static int yaffs_SoftDeleteWorker(yaffs_Object *in, yaffs_Tnode *tn,
1722                                   __u32 level, int chunkOffset)
1723 {
1724         int i;
1725         int theChunk;
1726         int allDone = 1;
1727         yaffs_Device *dev = in->myDev;
1728
1729         if (tn) {
1730                 if (level > 0) {
1731
1732                         for (i = YAFFS_NTNODES_INTERNAL - 1; allDone && i >= 0;
1733                              i--) {
1734                                 if (tn->internal[i]) {
1735                                         allDone =
1736                                             yaffs_SoftDeleteWorker(in,
1737                                                                    tn->
1738                                                                    internal[i],
1739                                                                    level - 1,
1740                                                                    (chunkOffset
1741                                                                     <<
1742                                                                     YAFFS_TNODES_INTERNAL_BITS)
1743                                                                    + i);
1744                                         if (allDone) {
1745                                                 yaffs_FreeTnode(dev,
1746                                                                 tn->
1747                                                                 internal[i]);
1748                                                 tn->internal[i] = NULL;
1749                                         } else {
1750                                                 /* Hoosterman... how could this happen? */
1751                                         }
1752                                 }
1753                         }
1754                         return (allDone) ? 1 : 0;
1755                 } else if (level == 0) {
1756
1757                         for (i = YAFFS_NTNODES_LEVEL0 - 1; i >= 0; i--) {
1758                                 theChunk = yaffs_GetChunkGroupBase(dev, tn, i);
1759                                 if (theChunk) {
1760                                         /* Note this does not find the real chunk, only the chunk group.
1761                                          * We make an assumption that a chunk group is not larger than
1762                                          * a block.
1763                                          */
1764                                         yaffs_SoftDeleteChunk(dev, theChunk);
1765                                         yaffs_LoadLevel0Tnode(dev, tn, i, 0);
1766                                 }
1767
1768                         }
1769                         return 1;
1770
1771                 }
1772
1773         }
1774
1775         return 1;
1776
1777 }
1778
1779 static void yaffs_SoftDeleteFile(yaffs_Object *obj)
1780 {
1781         if (obj->deleted &&
1782             obj->variantType == YAFFS_OBJECT_TYPE_FILE && !obj->softDeleted) {
1783                 if (obj->nDataChunks <= 0) {
1784                         /* Empty file with no duplicate object headers, just delete it immediately */
1785                         yaffs_FreeTnode(obj->myDev,
1786                                         obj->variant.fileVariant.top);
1787                         obj->variant.fileVariant.top = NULL;
1788                         T(YAFFS_TRACE_TRACING,
1789                           (TSTR("yaffs: Deleting empty file %d" TENDSTR),
1790                            obj->objectId));
1791                         yaffs_DoGenericObjectDeletion(obj);
1792                 } else {
1793                         yaffs_SoftDeleteWorker(obj,
1794                                                obj->variant.fileVariant.top,
1795                                                obj->variant.fileVariant.
1796                                                topLevel, 0);
1797                         obj->softDeleted = 1;
1798                 }
1799         }
1800 }
1801
1802 /* Pruning removes any part of the file structure tree that is beyond the
1803  * bounds of the file (ie that does not point to chunks).
1804  *
1805  * A file should only get pruned when its size is reduced.
1806  *
1807  * Before pruning, the chunks must be pulled from the tree and the
1808  * level 0 tnode entries must be zeroed out.
1809  * Could also use this for file deletion, but that's probably better handled
1810  * by a special case.
1811  *
1812  * This function is recursive. For levels > 0 the function is called again on
1813  * any sub-tree. For level == 0 we just check if the sub-tree has data.
1814  * If there is no data in a subtree then it is pruned.
1815  */
1816
1817 static yaffs_Tnode *yaffs_PruneWorker(yaffs_Device *dev, yaffs_Tnode *tn,
1818                                 __u32 level, int del0)
1819 {
1820         int i;
1821         int hasData;
1822
1823         if (tn) {
1824                 hasData = 0;
1825
1826                 if(level > 0){
1827                         for (i = 0; i < YAFFS_NTNODES_INTERNAL; i++) {
1828                                 if (tn->internal[i]) {
1829                                         tn->internal[i] =
1830                                                 yaffs_PruneWorker(dev, tn->internal[i],
1831                                                         level - 1,
1832                                                         (i == 0) ? del0 : 1);
1833                                 }
1834
1835                                 if (tn->internal[i])
1836                                         hasData++;
1837                         }
1838                 } else {
1839                         int tnodeSize;
1840                         __u32 *map = (__u32 *)tn;
1841                         tnodeSize = (dev->tnodeWidth * YAFFS_NTNODES_LEVEL0)/8;
1842
1843                         if (tnodeSize < sizeof(yaffs_Tnode))
1844                                 tnodeSize = sizeof(yaffs_Tnode);
1845                         tnodeSize /= sizeof(__u32);
1846
1847                         for(i = 0; !hasData && i < tnodeSize; i++){
1848                                 if(map[i])
1849                                         hasData++;
1850                         }
1851                 }
1852
1853                 if (hasData == 0 && del0) {
1854                         /* Free and return NULL */
1855
1856                         yaffs_FreeTnode(dev, tn);
1857                         tn = NULL;
1858                 }
1859
1860         }
1861
1862         return tn;
1863
1864 }
1865
1866 static int yaffs_PruneFileStructure(yaffs_Device *dev,
1867                                 yaffs_FileStructure *fStruct)
1868 {
1869         int i;
1870         int hasData;
1871         int done = 0;
1872         yaffs_Tnode *tn;
1873
1874         if (fStruct->topLevel > 0) {
1875                 fStruct->top =
1876                     yaffs_PruneWorker(dev, fStruct->top, fStruct->topLevel, 0);
1877
1878                 /* Now we have a tree with all the non-zero branches NULL but the height
1879                  * is the same as it was.
1880                  * Let's see if we can trim internal tnodes to shorten the tree.
1881                  * We can do this if only the 0th element in the tnode is in use
1882                  * (ie all the non-zero are NULL)
1883                  */
1884
1885                 while (fStruct->topLevel && !done) {
1886                         tn = fStruct->top;
1887
1888                         hasData = 0;
1889                         for (i = 1; i < YAFFS_NTNODES_INTERNAL; i++) {
1890                                 if (tn->internal[i])
1891                                         hasData++;
1892                         }
1893
1894                         if (!hasData) {
1895                                 fStruct->top = tn->internal[0];
1896                                 fStruct->topLevel--;
1897                                 yaffs_FreeTnode(dev, tn);
1898                         } else {
1899                                 done = 1;
1900                         }
1901                 }
1902         }
1903
1904         return YAFFS_OK;
1905 }
1906
1907 /*-------------------- End of File Structure functions.-------------------*/
1908
1909 /* yaffs_CreateFreeObjects creates a bunch more objects and
1910  * adds them to the object free list.
1911  */
1912 static int yaffs_CreateFreeObjects(yaffs_Device *dev, int nObjects)
1913 {
1914         int i;
1915         yaffs_Object *newObjects;
1916         yaffs_ObjectList *list;
1917
1918         if (nObjects < 1)
1919                 return YAFFS_OK;
1920
1921         /* make these things */
1922         newObjects = YMALLOC(nObjects * sizeof(yaffs_Object));
1923         list = YMALLOC(sizeof(yaffs_ObjectList));
1924
1925         if (!newObjects || !list) {
1926                 if (newObjects){
1927                         YFREE(newObjects);
1928                         newObjects = NULL;
1929                 }
1930                 if (list){
1931                         YFREE(list);
1932                         list = NULL;
1933                 }
1934                 T(YAFFS_TRACE_ALLOCATE,
1935                   (TSTR("yaffs: Could not allocate more objects" TENDSTR)));
1936                 return YAFFS_FAIL;
1937         }
1938
1939         /* Hook them into the free list */
1940         for (i = 0; i < nObjects - 1; i++) {
1941                 newObjects[i].siblings.next =
1942                                 (struct ylist_head *)(&newObjects[i + 1]);
1943         }
1944
1945         newObjects[nObjects - 1].siblings.next = (void *)dev->freeObjects;
1946         dev->freeObjects = newObjects;
1947         dev->nFreeObjects += nObjects;
1948         dev->nObjectsCreated += nObjects;
1949
1950         /* Now add this bunch of Objects to a list for freeing up. */
1951
1952         list->objects = newObjects;
1953         list->next = dev->allocatedObjectList;
1954         dev->allocatedObjectList = list;
1955
1956         return YAFFS_OK;
1957 }
1958
1959
1960 /* AllocateEmptyObject gets us a clean Object. Tries to make allocate more if we run out */
1961 static yaffs_Object *yaffs_AllocateEmptyObject(yaffs_Device *dev)
1962 {
1963         yaffs_Object *tn = NULL;
1964
1965 #ifdef VALGRIND_TEST
1966         tn = YMALLOC(sizeof(yaffs_Object));
1967 #else
1968         /* If there are none left make more */
1969         if (!dev->freeObjects)
1970                 yaffs_CreateFreeObjects(dev, YAFFS_ALLOCATION_NOBJECTS);
1971
1972         if (dev->freeObjects) {
1973                 tn = dev->freeObjects;
1974                 dev->freeObjects =
1975                         (yaffs_Object *) (dev->freeObjects->siblings.next);
1976                 dev->nFreeObjects--;
1977         }
1978 #endif
1979         if (tn) {
1980                 /* Now sweeten it up... */
1981
1982                 memset(tn, 0, sizeof(yaffs_Object));
1983                 tn->beingCreated = 1;
1984
1985                 tn->myDev = dev;
1986                 tn->hdrChunk = 0;
1987                 tn->variantType = YAFFS_OBJECT_TYPE_UNKNOWN;
1988                 YINIT_LIST_HEAD(&(tn->hardLinks));
1989                 YINIT_LIST_HEAD(&(tn->hashLink));
1990                 YINIT_LIST_HEAD(&tn->siblings);
1991
1992
1993                 /* Now make the directory sane */
1994                 if (dev->rootDir) {
1995                         tn->parent = dev->rootDir;
1996                         ylist_add(&(tn->siblings), &dev->rootDir->variant.directoryVariant.children);
1997                 }
1998
1999                 /* Add it to the lost and found directory.
2000                  * NB Can't put root or lostNFound in lostNFound so
2001                  * check if lostNFound exists first
2002                  */
2003                 if (dev->lostNFoundDir)
2004                         yaffs_AddObjectToDirectory(dev->lostNFoundDir, tn);
2005
2006                 tn->beingCreated = 0;
2007         }
2008
2009         dev->nCheckpointBlocksRequired = 0; /* force recalculation*/
2010
2011         return tn;
2012 }
2013
2014 static yaffs_Object *yaffs_CreateFakeDirectory(yaffs_Device *dev, int number,
2015                                                __u32 mode)
2016 {
2017
2018         yaffs_Object *obj =
2019             yaffs_CreateNewObject(dev, number, YAFFS_OBJECT_TYPE_DIRECTORY);
2020         if (obj) {
2021                 obj->fake = 1;          /* it is fake so it might have no NAND presence... */
2022                 obj->renameAllowed = 0; /* ... and we're not allowed to rename it... */
2023                 obj->unlinkAllowed = 0; /* ... or unlink it */
2024                 obj->deleted = 0;
2025                 obj->unlinked = 0;
2026                 obj->yst_mode = mode;
2027                 obj->myDev = dev;
2028                 obj->hdrChunk = 0;      /* Not a valid chunk. */
2029         }
2030
2031         return obj;
2032
2033 }
2034
2035 static void yaffs_UnhashObject(yaffs_Object *tn)
2036 {
2037         int bucket;
2038         yaffs_Device *dev = tn->myDev;
2039
2040         /* If it is still linked into the bucket list, free from the list */
2041         if (!ylist_empty(&tn->hashLink)) {
2042                 ylist_del_init(&tn->hashLink);
2043                 bucket = yaffs_HashFunction(tn->objectId);
2044                 dev->objectBucket[bucket].count--;
2045         }
2046 }
2047
2048 /*  FreeObject frees up a Object and puts it back on the free list */
2049 static void yaffs_FreeObject(yaffs_Object *tn)
2050 {
2051         yaffs_Device *dev = tn->myDev;
2052
2053 #ifdef __KERNEL__
2054         T(YAFFS_TRACE_OS, (TSTR("FreeObject %p inode %p"TENDSTR), tn, tn->myInode));
2055 #endif
2056
2057         if (tn->parent)
2058                 YBUG();
2059         if (!ylist_empty(&tn->siblings))
2060                 YBUG();
2061
2062
2063 #ifdef __KERNEL__
2064         if (tn->myInode) {
2065                 /* We're still hooked up to a cached inode.
2066                  * Don't delete now, but mark for later deletion
2067                  */
2068                 tn->deferedFree = 1;
2069                 return;
2070         }
2071 #endif
2072
2073         yaffs_UnhashObject(tn);
2074
2075 #ifdef VALGRIND_TEST
2076         YFREE(tn);
2077         tn = NULL;
2078 #else
2079         /* Link into the free list. */
2080         tn->siblings.next = (struct ylist_head *)(dev->freeObjects);
2081         dev->freeObjects = tn;
2082         dev->nFreeObjects++;
2083 #endif
2084         dev->nCheckpointBlocksRequired = 0; /* force recalculation*/
2085 }
2086
2087 #ifdef __KERNEL__
2088
2089 void yaffs_HandleDeferedFree(yaffs_Object *obj)
2090 {
2091         if (obj->deferedFree)
2092                 yaffs_FreeObject(obj);
2093 }
2094
2095 #endif
2096
2097 static void yaffs_DeinitialiseObjects(yaffs_Device *dev)
2098 {
2099         /* Free the list of allocated Objects */
2100
2101         yaffs_ObjectList *tmp;
2102
2103         while (dev->allocatedObjectList) {
2104                 tmp = dev->allocatedObjectList->next;
2105                 YFREE(dev->allocatedObjectList->objects);
2106                 YFREE(dev->allocatedObjectList);
2107
2108                 dev->allocatedObjectList = tmp;
2109         }
2110
2111         dev->freeObjects = NULL;
2112         dev->nFreeObjects = 0;
2113         dev->nObjectsCreated = 0;
2114 }
2115
2116 static void yaffs_InitialiseObjects(yaffs_Device *dev)
2117 {
2118         int i;
2119
2120         dev->allocatedObjectList = NULL;
2121         dev->freeObjects = NULL;
2122         dev->nFreeObjects = 0;
2123
2124         for (i = 0; i < YAFFS_NOBJECT_BUCKETS; i++) {
2125                 YINIT_LIST_HEAD(&dev->objectBucket[i].list);
2126                 dev->objectBucket[i].count = 0;
2127         }
2128 }
2129
2130 static int yaffs_FindNiceObjectBucket(yaffs_Device *dev)
2131 {
2132         static int x;
2133         int i;
2134         int l = 999;
2135         int lowest = 999999;
2136
2137         /* First let's see if we can find one that's empty. */
2138
2139         for (i = 0; i < 10 && lowest > 0; i++) {
2140                 x++;
2141                 x %= YAFFS_NOBJECT_BUCKETS;
2142                 if (dev->objectBucket[x].count < lowest) {
2143                         lowest = dev->objectBucket[x].count;
2144                         l = x;
2145                 }
2146
2147         }
2148
2149         /* If we didn't find an empty list, then try
2150          * looking a bit further for a short one
2151          */
2152
2153         for (i = 0; i < 10 && lowest > 3; i++) {
2154                 x++;
2155                 x %= YAFFS_NOBJECT_BUCKETS;
2156                 if (dev->objectBucket[x].count < lowest) {
2157                         lowest = dev->objectBucket[x].count;
2158                         l = x;
2159                 }
2160
2161         }
2162
2163         return l;
2164 }
2165
2166 static int yaffs_CreateNewObjectNumber(yaffs_Device *dev)
2167 {
2168         int bucket = yaffs_FindNiceObjectBucket(dev);
2169
2170         /* Now find an object value that has not already been taken
2171          * by scanning the list.
2172          */
2173
2174         int found = 0;
2175         struct ylist_head *i;
2176
2177         __u32 n = (__u32) bucket;
2178
2179         /* yaffs_CheckObjectHashSanity();  */
2180
2181         while (!found) {
2182                 found = 1;
2183                 n += YAFFS_NOBJECT_BUCKETS;
2184                 if (1 || dev->objectBucket[bucket].count > 0) {
2185                         ylist_for_each(i, &dev->objectBucket[bucket].list) {
2186                                 /* If there is already one in the list */
2187                                 if (i && ylist_entry(i, yaffs_Object,
2188                                                 hashLink)->objectId == n) {
2189                                         found = 0;
2190                                 }
2191                         }
2192                 }
2193         }
2194
2195         return n;
2196 }
2197
2198 static void yaffs_HashObject(yaffs_Object *in)
2199 {
2200         int bucket = yaffs_HashFunction(in->objectId);
2201         yaffs_Device *dev = in->myDev;
2202
2203         ylist_add(&in->hashLink, &dev->objectBucket[bucket].list);
2204         dev->objectBucket[bucket].count++;
2205 }
2206
2207 yaffs_Object *yaffs_FindObjectByNumber(yaffs_Device *dev, __u32 number)
2208 {
2209         int bucket = yaffs_HashFunction(number);
2210         struct ylist_head *i;
2211         yaffs_Object *in;
2212
2213         ylist_for_each(i, &dev->objectBucket[bucket].list) {
2214                 /* Look if it is in the list */
2215                 if (i) {
2216                         in = ylist_entry(i, yaffs_Object, hashLink);
2217                         if (in->objectId == number) {
2218 #ifdef __KERNEL__
2219                                 /* Don't tell the VFS about this one if it is defered free */
2220                                 if (in->deferedFree)
2221                                         return NULL;
2222 #endif
2223
2224                                 return in;
2225                         }
2226                 }
2227         }
2228
2229         return NULL;
2230 }
2231
2232 yaffs_Object *yaffs_CreateNewObject(yaffs_Device *dev, int number,
2233                                     yaffs_ObjectType type)
2234 {
2235         yaffs_Object *theObject;
2236         yaffs_Tnode *tn = NULL;
2237
2238         if (number < 0)
2239                 number = yaffs_CreateNewObjectNumber(dev);
2240
2241         if (type == YAFFS_OBJECT_TYPE_FILE) {
2242                 tn = yaffs_GetTnode(dev);
2243                 if (!tn)
2244                         return NULL;
2245         }
2246
2247         theObject = yaffs_AllocateEmptyObject(dev);
2248         if (!theObject){
2249                 if(tn)
2250                         yaffs_FreeTnode(dev,tn);
2251                 return NULL;
2252         }
2253
2254
2255         if (theObject) {
2256                 theObject->fake = 0;
2257                 theObject->renameAllowed = 1;
2258                 theObject->unlinkAllowed = 1;
2259                 theObject->objectId = number;
2260                 yaffs_HashObject(theObject);
2261                 theObject->variantType = type;
2262 #ifdef CONFIG_YAFFS_WINCE
2263                 yfsd_WinFileTimeNow(theObject->win_atime);
2264                 theObject->win_ctime[0] = theObject->win_mtime[0] =
2265                     theObject->win_atime[0];
2266                 theObject->win_ctime[1] = theObject->win_mtime[1] =
2267                     theObject->win_atime[1];
2268
2269 #else
2270
2271                 theObject->yst_atime = theObject->yst_mtime =
2272                     theObject->yst_ctime = Y_CURRENT_TIME;
2273 #endif
2274                 switch (type) {
2275                 case YAFFS_OBJECT_TYPE_FILE:
2276                         theObject->variant.fileVariant.fileSize = 0;
2277                         theObject->variant.fileVariant.scannedFileSize = 0;
2278                         theObject->variant.fileVariant.shrinkSize = 0xFFFFFFFF; /* max __u32 */
2279                         theObject->variant.fileVariant.topLevel = 0;
2280                         theObject->variant.fileVariant.top = tn;
2281                         break;
2282                 case YAFFS_OBJECT_TYPE_DIRECTORY:
2283                         YINIT_LIST_HEAD(&theObject->variant.directoryVariant.
2284                                         children);
2285                         break;
2286                 case YAFFS_OBJECT_TYPE_SYMLINK:
2287                 case YAFFS_OBJECT_TYPE_HARDLINK:
2288                 case YAFFS_OBJECT_TYPE_SPECIAL:
2289                         /* No action required */
2290                         break;
2291                 case YAFFS_OBJECT_TYPE_UNKNOWN:
2292                         /* todo this should not happen */
2293                         break;
2294                 }
2295         }
2296
2297         return theObject;
2298 }
2299
2300 static yaffs_Object *yaffs_FindOrCreateObjectByNumber(yaffs_Device *dev,
2301                                                       int number,
2302                                                       yaffs_ObjectType type)
2303 {
2304         yaffs_Object *theObject = NULL;
2305
2306         if (number > 0)
2307                 theObject = yaffs_FindObjectByNumber(dev, number);
2308
2309         if (!theObject)
2310                 theObject = yaffs_CreateNewObject(dev, number, type);
2311
2312         return theObject;
2313
2314 }
2315
2316
2317 static YCHAR *yaffs_CloneString(const YCHAR *str)
2318 {
2319         YCHAR *newStr = NULL;
2320         int len;
2321
2322         if (!str)
2323                 str = _Y("");
2324
2325         len = yaffs_strnlen(str,YAFFS_MAX_ALIAS_LENGTH);
2326         newStr = YMALLOC((len + 1) * sizeof(YCHAR));
2327         if (newStr){
2328                 yaffs_strncpy(newStr, str,len);
2329                 newStr[len] = 0;
2330         }
2331         return newStr;
2332
2333 }
2334
2335 /*
2336  * Mknod (create) a new object.
2337  * equivalentObject only has meaning for a hard link;
2338  * aliasString only has meaning for a symlink.
2339  * rdev only has meaning for devices (a subset of special objects)
2340  */
2341
2342 static yaffs_Object *yaffs_MknodObject(yaffs_ObjectType type,
2343                                        yaffs_Object *parent,
2344                                        const YCHAR *name,
2345                                        __u32 mode,
2346                                        __u32 uid,
2347                                        __u32 gid,
2348                                        yaffs_Object *equivalentObject,
2349                                        const YCHAR *aliasString, __u32 rdev)
2350 {
2351         yaffs_Object *in;
2352         YCHAR *str = NULL;
2353
2354         yaffs_Device *dev = parent->myDev;
2355
2356         /* Check if the entry exists. If it does then fail the call since we don't want a dup.*/
2357         if (yaffs_FindObjectByName(parent, name))
2358                 return NULL;
2359
2360         if (type == YAFFS_OBJECT_TYPE_SYMLINK) {
2361                 str = yaffs_CloneString(aliasString);
2362                 if (!str)
2363                         return NULL;
2364         }
2365
2366         in = yaffs_CreateNewObject(dev, -1, type);
2367
2368         if (!in){
2369                 if(str)
2370                         YFREE(str);
2371                 return NULL;
2372         }
2373
2374
2375
2376
2377         if (in) {
2378                 in->hdrChunk = 0;
2379                 in->valid = 1;
2380                 in->variantType = type;
2381
2382                 in->yst_mode = mode;
2383
2384 #ifdef CONFIG_YAFFS_WINCE
2385                 yfsd_WinFileTimeNow(in->win_atime);
2386                 in->win_ctime[0] = in->win_mtime[0] = in->win_atime[0];
2387                 in->win_ctime[1] = in->win_mtime[1] = in->win_atime[1];
2388
2389 #else
2390                 in->yst_atime = in->yst_mtime = in->yst_ctime = Y_CURRENT_TIME;
2391
2392                 in->yst_rdev = rdev;
2393                 in->yst_uid = uid;
2394                 in->yst_gid = gid;
2395 #endif
2396                 in->nDataChunks = 0;
2397
2398                 yaffs_SetObjectName(in, name);
2399                 in->dirty = 1;
2400
2401                 yaffs_AddObjectToDirectory(parent, in);
2402
2403                 in->myDev = parent->myDev;
2404
2405                 switch (type) {
2406                 case YAFFS_OBJECT_TYPE_SYMLINK:
2407                         in->variant.symLinkVariant.alias = str;
2408                         break;
2409                 case YAFFS_OBJECT_TYPE_HARDLINK:
2410                         in->variant.hardLinkVariant.equivalentObject =
2411                                 equivalentObject;
2412                         in->variant.hardLinkVariant.equivalentObjectId =
2413                                 equivalentObject->objectId;
2414                         ylist_add(&in->hardLinks, &equivalentObject->hardLinks);
2415                         break;
2416                 case YAFFS_OBJECT_TYPE_FILE:
2417                 case YAFFS_OBJECT_TYPE_DIRECTORY:
2418                 case YAFFS_OBJECT_TYPE_SPECIAL:
2419                 case YAFFS_OBJECT_TYPE_UNKNOWN:
2420                         /* do nothing */
2421                         break;
2422                 }
2423
2424                 if (yaffs_UpdateObjectHeader(in, name, 0, 0, 0) < 0) {
2425                         /* Could not create the object header, fail the creation */
2426                         yaffs_DeleteObject(in);
2427                         in = NULL;
2428                 }
2429
2430                 yaffs_UpdateParent(parent);
2431         }
2432
2433         return in;
2434 }
2435
2436 yaffs_Object *yaffs_MknodFile(yaffs_Object *parent, const YCHAR *name,
2437                         __u32 mode, __u32 uid, __u32 gid)
2438 {
2439         return yaffs_MknodObject(YAFFS_OBJECT_TYPE_FILE, parent, name, mode,
2440                                 uid, gid, NULL, NULL, 0);
2441 }
2442
2443 yaffs_Object *yaffs_MknodDirectory(yaffs_Object *parent, const YCHAR *name,
2444                                 __u32 mode, __u32 uid, __u32 gid)
2445 {
2446         return yaffs_MknodObject(YAFFS_OBJECT_TYPE_DIRECTORY, parent, name,
2447                                  mode, uid, gid, NULL, NULL, 0);
2448 }
2449
2450 yaffs_Object *yaffs_MknodSpecial(yaffs_Object *parent, const YCHAR *name,
2451                                 __u32 mode, __u32 uid, __u32 gid, __u32 rdev)
2452 {
2453         return yaffs_MknodObject(YAFFS_OBJECT_TYPE_SPECIAL, parent, name, mode,
2454                                  uid, gid, NULL, NULL, rdev);
2455 }
2456
2457 yaffs_Object *yaffs_MknodSymLink(yaffs_Object *parent, const YCHAR *name,
2458                                 __u32 mode, __u32 uid, __u32 gid,
2459                                 const YCHAR *alias)
2460 {
2461         return yaffs_MknodObject(YAFFS_OBJECT_TYPE_SYMLINK, parent, name, mode,
2462                                 uid, gid, NULL, alias, 0);
2463 }
2464
2465 /* yaffs_Link returns the object id of the equivalent object.*/
2466 yaffs_Object *yaffs_Link(yaffs_Object *parent, const YCHAR *name,
2467                         yaffs_Object *equivalentObject)
2468 {
2469         /* Get the real object in case we were fed a hard link as an equivalent object */
2470         equivalentObject = yaffs_GetEquivalentObject(equivalentObject);
2471
2472         if (yaffs_MknodObject
2473             (YAFFS_OBJECT_TYPE_HARDLINK, parent, name, 0, 0, 0,
2474              equivalentObject, NULL, 0)) {
2475                 return equivalentObject;
2476         } else {
2477                 return NULL;
2478         }
2479
2480 }
2481
2482 static int yaffs_ChangeObjectName(yaffs_Object *obj, yaffs_Object *newDir,
2483                                 const YCHAR *newName, int force, int shadows)
2484 {
2485         int unlinkOp;
2486         int deleteOp;
2487
2488         yaffs_Object *existingTarget;
2489
2490         if (newDir == NULL)
2491                 newDir = obj->parent;   /* use the old directory */
2492
2493         if (newDir->variantType != YAFFS_OBJECT_TYPE_DIRECTORY) {
2494                 T(YAFFS_TRACE_ALWAYS,
2495                   (TSTR
2496                    ("tragedy: yaffs_ChangeObjectName: newDir is not a directory"
2497                     TENDSTR)));
2498                 YBUG();
2499         }
2500
2501         /* TODO: Do we need this different handling for YAFFS2 and YAFFS1?? */
2502         if (obj->myDev->isYaffs2)
2503                 unlinkOp = (newDir == obj->myDev->unlinkedDir);
2504         else
2505                 unlinkOp = (newDir == obj->myDev->unlinkedDir
2506                             && obj->variantType == YAFFS_OBJECT_TYPE_FILE);
2507
2508         deleteOp = (newDir == obj->myDev->deletedDir);
2509
2510         existingTarget = yaffs_FindObjectByName(newDir, newName);
2511
2512         /* If the object is a file going into the unlinked directory,
2513          *   then it is OK to just stuff it in since duplicate names are allowed.
2514          *   else only proceed if the new name does not exist and if we're putting
2515          *   it into a directory.
2516          */
2517         if ((unlinkOp ||
2518              deleteOp ||
2519              force ||
2520              (shadows > 0) ||
2521              !existingTarget) &&
2522             newDir->variantType == YAFFS_OBJECT_TYPE_DIRECTORY) {
2523                 yaffs_SetObjectName(obj, newName);
2524                 obj->dirty = 1;
2525
2526                 yaffs_AddObjectToDirectory(newDir, obj);
2527
2528                 if (unlinkOp)
2529                         obj->unlinked = 1;
2530
2531                 /* If it is a deletion then we mark it as a shrink for gc purposes. */
2532                 if (yaffs_UpdateObjectHeader(obj, newName, 0, deleteOp, shadows) >= 0)
2533                         return YAFFS_OK;
2534         }
2535
2536         return YAFFS_FAIL;
2537 }
2538
2539 int yaffs_RenameObject(yaffs_Object *oldDir, const YCHAR *oldName,
2540                 yaffs_Object *newDir, const YCHAR *newName)
2541 {
2542         yaffs_Object *obj = NULL;
2543         yaffs_Object *existingTarget = NULL;
2544         int force = 0;
2545         int result;
2546         yaffs_Device *dev;
2547
2548
2549         if (!oldDir || oldDir->variantType != YAFFS_OBJECT_TYPE_DIRECTORY)
2550                 YBUG();
2551         if (!newDir || newDir->variantType != YAFFS_OBJECT_TYPE_DIRECTORY)
2552                 YBUG();
2553
2554         dev = oldDir->myDev;
2555
2556 #ifdef CONFIG_YAFFS_CASE_INSENSITIVE
2557         /* Special case for case insemsitive systems (eg. WinCE).
2558          * While look-up is case insensitive, the name isn't.
2559          * Therefore we might want to change x.txt to X.txt
2560         */
2561         if (oldDir == newDir && yaffs_strcmp(oldName, newName) == 0)
2562                 force = 1;
2563 #endif
2564
2565         if(yaffs_strnlen(newName,YAFFS_MAX_NAME_LENGTH+1) > YAFFS_MAX_NAME_LENGTH)
2566                 /* ENAMETOOLONG */
2567                 return YAFFS_FAIL;
2568
2569         obj = yaffs_FindObjectByName(oldDir, oldName);
2570
2571         if (obj && obj->renameAllowed) {
2572
2573                 /* Now do the handling for an existing target, if there is one */
2574
2575                 existingTarget = yaffs_FindObjectByName(newDir, newName);
2576                 if (existingTarget &&
2577                         existingTarget->variantType == YAFFS_OBJECT_TYPE_DIRECTORY &&
2578                         !ylist_empty(&existingTarget->variant.directoryVariant.children)) {
2579                         /* There is a target that is a non-empty directory, so we fail */
2580                         return YAFFS_FAIL;      /* EEXIST or ENOTEMPTY */
2581                 } else if (existingTarget && existingTarget != obj) {
2582                         /* Nuke the target first, using shadowing,
2583                          * but only if it isn't the same object.
2584                          *
2585                          * Note we must disable gc otherwise it can mess up the shadowing.
2586                          *
2587                          */
2588                         dev->isDoingGC=1;
2589                         yaffs_ChangeObjectName(obj, newDir, newName, force,
2590                                                 existingTarget->objectId);
2591                         existingTarget->isShadowed = 1;
2592                         yaffs_UnlinkObject(existingTarget);
2593                         dev->isDoingGC=0;
2594                 }
2595
2596                 result = yaffs_ChangeObjectName(obj, newDir, newName, 1, 0);
2597
2598                 yaffs_UpdateParent(oldDir);
2599                 if(newDir != oldDir)
2600                         yaffs_UpdateParent(newDir);
2601                 
2602                 return result;
2603         }
2604         return YAFFS_FAIL;
2605 }
2606
2607 /*------------------------- Block Management and Page Allocation ----------------*/
2608
2609 static int yaffs_InitialiseBlocks(yaffs_Device *dev)
2610 {
2611         int nBlocks = dev->internalEndBlock - dev->internalStartBlock + 1;
2612
2613         dev->blockInfo = NULL;
2614         dev->chunkBits = NULL;
2615
2616         dev->allocationBlock = -1;      /* force it to get a new one */
2617
2618         /* If the first allocation strategy fails, thry the alternate one */
2619         dev->blockInfo = YMALLOC(nBlocks * sizeof(yaffs_BlockInfo));
2620         if (!dev->blockInfo) {
2621                 dev->blockInfo = YMALLOC_ALT(nBlocks * sizeof(yaffs_BlockInfo));
2622                 dev->blockInfoAlt = 1;
2623         } else
2624                 dev->blockInfoAlt = 0;
2625
2626         if (dev->blockInfo) {
2627                 /* Set up dynamic blockinfo stuff. */
2628                 dev->chunkBitmapStride = (dev->nChunksPerBlock + 7) / 8; /* round up bytes */
2629                 dev->chunkBits = YMALLOC(dev->chunkBitmapStride * nBlocks);
2630                 if (!dev->chunkBits) {
2631                         dev->chunkBits = YMALLOC_ALT(dev->chunkBitmapStride * nBlocks);
2632                         dev->chunkBitsAlt = 1;
2633                 } else
2634                         dev->chunkBitsAlt = 0;
2635         }
2636
2637         if (dev->blockInfo && dev->chunkBits) {
2638                 memset(dev->blockInfo, 0, nBlocks * sizeof(yaffs_BlockInfo));
2639                 memset(dev->chunkBits, 0, dev->chunkBitmapStride * nBlocks);
2640                 return YAFFS_OK;
2641         }
2642
2643         return YAFFS_FAIL;
2644 }
2645
2646 static void yaffs_DeinitialiseBlocks(yaffs_Device *dev)
2647 {
2648         if (dev->blockInfoAlt && dev->blockInfo)
2649                 YFREE_ALT(dev->blockInfo);
2650         else if (dev->blockInfo)
2651                 YFREE(dev->blockInfo);
2652
2653         dev->blockInfoAlt = 0;
2654
2655         dev->blockInfo = NULL;
2656
2657         if (dev->chunkBitsAlt && dev->chunkBits)
2658                 YFREE_ALT(dev->chunkBits);
2659         else if (dev->chunkBits)
2660                 YFREE(dev->chunkBits);
2661         dev->chunkBitsAlt = 0;
2662         dev->chunkBits = NULL;
2663 }
2664
2665 static int yaffs_BlockNotDisqualifiedFromGC(yaffs_Device *dev,
2666                                         yaffs_BlockInfo *bi)
2667 {
2668         int i;
2669         __u32 seq;
2670         yaffs_BlockInfo *b;
2671
2672         if (!dev->isYaffs2)
2673                 return 1;       /* disqualification only applies to yaffs2. */
2674
2675         if (!bi->hasShrinkHeader)
2676                 return 1;       /* can gc */
2677
2678         /* Find the oldest dirty sequence number if we don't know it and save it
2679          * so we don't have to keep recomputing it.
2680          */
2681         if (!dev->oldestDirtySequence) {
2682                 seq = dev->sequenceNumber;
2683
2684                 for (i = dev->internalStartBlock; i <= dev->internalEndBlock;
2685                                 i++) {
2686                         b = yaffs_GetBlockInfo(dev, i);
2687                         if (b->blockState == YAFFS_BLOCK_STATE_FULL &&
2688                             (b->pagesInUse - b->softDeletions) <
2689                             dev->nChunksPerBlock && b->sequenceNumber < seq) {
2690                                 seq = b->sequenceNumber;
2691                         }
2692                 }
2693                 dev->oldestDirtySequence = seq;
2694         }
2695
2696         /* Can't do gc of this block if there are any blocks older than this one that have
2697          * discarded pages.
2698          */
2699         return (bi->sequenceNumber <= dev->oldestDirtySequence);
2700 }
2701
2702 /* FindDiretiestBlock is used to select the dirtiest block (or close enough)
2703  * for garbage collection.
2704  */
2705
2706 static int yaffs_FindBlockForGarbageCollection(yaffs_Device *dev,
2707                                         int aggressive)
2708 {
2709         int b = dev->currentDirtyChecker;
2710
2711         int i;
2712         int iterations;
2713         int dirtiest = -1;
2714         int pagesInUse = 0;
2715         int prioritised = 0;
2716         yaffs_BlockInfo *bi;
2717         int pendingPrioritisedExist = 0;
2718
2719         /* First let's see if we need to grab a prioritised block */
2720         if (dev->hasPendingPrioritisedGCs) {
2721                 for (i = dev->internalStartBlock; i < dev->internalEndBlock && !prioritised; i++) {
2722
2723                         bi = yaffs_GetBlockInfo(dev, i);
2724                         /* yaffs_VerifyBlock(dev,bi,i); */
2725
2726                         if (bi->gcPrioritise) {
2727                                 pendingPrioritisedExist = 1;
2728                                 if (bi->blockState == YAFFS_BLOCK_STATE_FULL &&
2729                                    yaffs_BlockNotDisqualifiedFromGC(dev, bi)) {
2730                                         pagesInUse = (bi->pagesInUse - bi->softDeletions);
2731                                         dirtiest = i;
2732                                         prioritised = 1;
2733                                         aggressive = 1; /* Fool the non-aggressive skip logiv below */
2734                                 }
2735                         }
2736                 }
2737
2738                 if (!pendingPrioritisedExist) /* None found, so we can clear this */
2739                         dev->hasPendingPrioritisedGCs = 0;
2740         }
2741
2742         /* If we're doing aggressive GC then we are happy to take a less-dirty block, and
2743          * search harder.
2744          * else (we're doing a leasurely gc), then we only bother to do this if the
2745          * block has only a few pages in use.
2746          */
2747
2748         dev->nonAggressiveSkip--;
2749
2750         if (!aggressive && (dev->nonAggressiveSkip > 0))
2751                 return -1;
2752
2753         if (!prioritised)
2754                 pagesInUse =
2755                         (aggressive) ? dev->nChunksPerBlock : YAFFS_PASSIVE_GC_CHUNKS + 1;
2756
2757         if (aggressive)
2758                 iterations =
2759                     dev->internalEndBlock - dev->internalStartBlock + 1;
2760         else {
2761                 iterations =
2762                     dev->internalEndBlock - dev->internalStartBlock + 1;
2763                 iterations = iterations / 16;
2764                 if (iterations > 200)
2765                         iterations = 200;
2766         }
2767
2768         for (i = 0; i <= iterations && pagesInUse > 0 && !prioritised; i++) {
2769                 b++;
2770                 if (b < dev->internalStartBlock || b > dev->internalEndBlock)
2771                         b = dev->internalStartBlock;
2772
2773                 if (b < dev->internalStartBlock || b > dev->internalEndBlock) {
2774                         T(YAFFS_TRACE_ERROR,
2775                           (TSTR("**>> Block %d is not valid" TENDSTR), b));
2776                         YBUG();
2777                 }
2778
2779                 bi = yaffs_GetBlockInfo(dev, b);
2780
2781                 if (bi->blockState == YAFFS_BLOCK_STATE_FULL &&
2782                         (bi->pagesInUse - bi->softDeletions) < pagesInUse &&
2783                                 yaffs_BlockNotDisqualifiedFromGC(dev, bi)) {
2784                         dirtiest = b;
2785                         pagesInUse = (bi->pagesInUse - bi->softDeletions);
2786                 }
2787         }
2788
2789         dev->currentDirtyChecker = b;
2790
2791         if (dirtiest > 0) {
2792                 T(YAFFS_TRACE_GC,
2793                   (TSTR("GC Selected block %d with %d free, prioritised:%d" TENDSTR), dirtiest,
2794                    dev->nChunksPerBlock - pagesInUse, prioritised));
2795         }
2796
2797         dev->oldestDirtySequence = 0;
2798
2799         if (dirtiest > 0)
2800                 dev->nonAggressiveSkip = 4;
2801
2802         return dirtiest;
2803 }
2804
2805 static void yaffs_BlockBecameDirty(yaffs_Device *dev, int blockNo)
2806 {
2807         yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, blockNo);
2808
2809         int erasedOk = 0;
2810
2811         /* If the block is still healthy erase it and mark as clean.
2812          * If the block has had a data failure, then retire it.
2813          */
2814
2815         T(YAFFS_TRACE_GC | YAFFS_TRACE_ERASE,
2816                 (TSTR("yaffs_BlockBecameDirty block %d state %d %s"TENDSTR),
2817                 blockNo, bi->blockState, (bi->needsRetiring) ? "needs retiring" : ""));
2818
2819         bi->blockState = YAFFS_BLOCK_STATE_DIRTY;
2820
2821         if (!bi->needsRetiring) {
2822                 yaffs_InvalidateCheckpoint(dev);
2823                 erasedOk = yaffs_EraseBlockInNAND(dev, blockNo);
2824                 if (!erasedOk) {
2825                         dev->nErasureFailures++;
2826                         T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
2827                           (TSTR("**>> Erasure failed %d" TENDSTR), blockNo));
2828                 }
2829         }
2830
2831         if (erasedOk &&
2832             ((yaffs_traceMask & YAFFS_TRACE_ERASE) || !yaffs_SkipVerification(dev))) {
2833                 int i;
2834                 for (i = 0; i < dev->nChunksPerBlock; i++) {
2835                         if (!yaffs_CheckChunkErased
2836                             (dev, blockNo * dev->nChunksPerBlock + i)) {
2837                                 T(YAFFS_TRACE_ERROR,
2838                                   (TSTR
2839                                    (">>Block %d erasure supposedly OK, but chunk %d not erased"
2840                                     TENDSTR), blockNo, i));
2841                         }
2842                 }
2843         }
2844
2845         if (erasedOk) {
2846                 /* Clean it up... */
2847                 bi->blockState = YAFFS_BLOCK_STATE_EMPTY;
2848                 dev->nErasedBlocks++;
2849                 bi->pagesInUse = 0;
2850                 bi->softDeletions = 0;
2851                 bi->hasShrinkHeader = 0;
2852                 bi->skipErasedCheck = 1;  /* This is clean, so no need to check */
2853                 bi->gcPrioritise = 0;
2854                 yaffs_ClearChunkBits(dev, blockNo);
2855
2856                 T(YAFFS_TRACE_ERASE,
2857                   (TSTR("Erased block %d" TENDSTR), blockNo));
2858         } else {
2859                 dev->nFreeChunks -= dev->nChunksPerBlock;       /* We lost a block of free space */
2860
2861                 yaffs_RetireBlock(dev, blockNo);
2862                 T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
2863                   (TSTR("**>> Block %d retired" TENDSTR), blockNo));
2864         }
2865 }
2866
2867 static int yaffs_FindBlockForAllocation(yaffs_Device *dev)
2868 {
2869         int i;
2870
2871         yaffs_BlockInfo *bi;
2872
2873         if (dev->nErasedBlocks < 1) {
2874                 /* Hoosterman we've got a problem.
2875                  * Can't get space to gc
2876                  */
2877                 T(YAFFS_TRACE_ERROR,
2878                   (TSTR("yaffs tragedy: no more erased blocks" TENDSTR)));
2879
2880                 return -1;
2881         }
2882
2883         /* Find an empty block. */
2884
2885         for (i = dev->internalStartBlock; i <= dev->internalEndBlock; i++) {
2886                 dev->allocationBlockFinder++;
2887                 if (dev->allocationBlockFinder < dev->internalStartBlock
2888                     || dev->allocationBlockFinder > dev->internalEndBlock) {
2889                         dev->allocationBlockFinder = dev->internalStartBlock;
2890                 }
2891
2892                 bi = yaffs_GetBlockInfo(dev, dev->allocationBlockFinder);
2893
2894                 if (bi->blockState == YAFFS_BLOCK_STATE_EMPTY) {
2895                         bi->blockState = YAFFS_BLOCK_STATE_ALLOCATING;
2896                         dev->sequenceNumber++;
2897                         bi->sequenceNumber = dev->sequenceNumber;
2898                         dev->nErasedBlocks--;
2899                         T(YAFFS_TRACE_ALLOCATE,
2900                           (TSTR("Allocated block %d, seq  %d, %d left" TENDSTR),
2901                            dev->allocationBlockFinder, dev->sequenceNumber,
2902                            dev->nErasedBlocks));
2903                         return dev->allocationBlockFinder;
2904                 }
2905         }
2906
2907         T(YAFFS_TRACE_ALWAYS,
2908           (TSTR
2909            ("yaffs tragedy: no more erased blocks, but there should have been %d"
2910             TENDSTR), dev->nErasedBlocks));
2911
2912         return -1;
2913 }
2914
2915
2916
2917 static int yaffs_CalcCheckpointBlocksRequired(yaffs_Device *dev)
2918 {
2919         if (!dev->nCheckpointBlocksRequired &&
2920            dev->isYaffs2) {
2921                 /* Not a valid value so recalculate */
2922                 int nBytes = 0;
2923                 int nBlocks;
2924                 int devBlocks = (dev->endBlock - dev->startBlock + 1);
2925                 int tnodeSize;
2926
2927                 tnodeSize = (dev->tnodeWidth * YAFFS_NTNODES_LEVEL0)/8;
2928
2929                 if (tnodeSize < sizeof(yaffs_Tnode))
2930                         tnodeSize = sizeof(yaffs_Tnode);
2931
2932                 nBytes += sizeof(yaffs_CheckpointValidity);
2933                 nBytes += sizeof(yaffs_CheckpointDevice);
2934                 nBytes += devBlocks * sizeof(yaffs_BlockInfo);
2935                 nBytes += devBlocks * dev->chunkBitmapStride;
2936                 nBytes += (sizeof(yaffs_CheckpointObject) + sizeof(__u32)) * (dev->nObjectsCreated - dev->nFreeObjects);
2937                 nBytes += (tnodeSize + sizeof(__u32)) * (dev->nTnodesCreated - dev->nFreeTnodes);
2938                 nBytes += sizeof(yaffs_CheckpointValidity);
2939                 nBytes += sizeof(__u32); /* checksum*/
2940
2941                 /* Round up and add 2 blocks to allow for some bad blocks, so add 3 */
2942
2943                 nBlocks = (nBytes/(dev->nDataBytesPerChunk * dev->nChunksPerBlock)) + 3;
2944
2945                 dev->nCheckpointBlocksRequired = nBlocks;
2946         }
2947
2948         return dev->nCheckpointBlocksRequired;
2949 }
2950
2951 /*
2952  * Check if there's space to allocate...
2953  * Thinks.... do we need top make this ths same as yaffs_GetFreeChunks()?
2954  */
2955 static int yaffs_CheckSpaceForAllocation(yaffs_Device *dev)
2956 {
2957         int reservedChunks;
2958         int reservedBlocks = dev->nReservedBlocks;
2959         int checkpointBlocks;
2960
2961         if (dev->isYaffs2) {
2962                 checkpointBlocks =  yaffs_CalcCheckpointBlocksRequired(dev) -
2963                                     dev->blocksInCheckpoint;
2964                 if (checkpointBlocks < 0)
2965                         checkpointBlocks = 0;
2966         } else {
2967                 checkpointBlocks = 0;
2968         }
2969
2970         reservedChunks = ((reservedBlocks + checkpointBlocks) * dev->nChunksPerBlock);
2971
2972         return (dev->nFreeChunks > reservedChunks);
2973 }
2974
2975 static int yaffs_AllocateChunk(yaffs_Device *dev, int useReserve,
2976                 yaffs_BlockInfo **blockUsedPtr)
2977 {
2978         int retVal;
2979         yaffs_BlockInfo *bi;
2980
2981         if (dev->allocationBlock < 0) {
2982                 /* Get next block to allocate off */
2983                 dev->allocationBlock = yaffs_FindBlockForAllocation(dev);
2984                 dev->allocationPage = 0;
2985         }
2986
2987         if (!useReserve && !yaffs_CheckSpaceForAllocation(dev)) {
2988                 /* Not enough space to allocate unless we're allowed to use the reserve. */
2989                 return -1;
2990         }
2991
2992         if (dev->nErasedBlocks < dev->nReservedBlocks
2993                         && dev->allocationPage == 0) {
2994                 T(YAFFS_TRACE_ALLOCATE, (TSTR("Allocating reserve" TENDSTR)));
2995         }
2996
2997         /* Next page please.... */
2998         if (dev->allocationBlock >= 0) {
2999                 bi = yaffs_GetBlockInfo(dev, dev->allocationBlock);
3000
3001                 retVal = (dev->allocationBlock * dev->nChunksPerBlock) +
3002                         dev->allocationPage;
3003                 bi->pagesInUse++;
3004                 yaffs_SetChunkBit(dev, dev->allocationBlock,
3005                                 dev->allocationPage);
3006
3007                 dev->allocationPage++;
3008
3009                 dev->nFreeChunks--;
3010
3011                 /* If the block is full set the state to full */
3012                 if (dev->allocationPage >= dev->nChunksPerBlock) {
3013                         bi->blockState = YAFFS_BLOCK_STATE_FULL;
3014                         dev->allocationBlock = -1;
3015                 }
3016
3017                 if (blockUsedPtr)
3018                         *blockUsedPtr = bi;
3019
3020                 return retVal;
3021         }
3022
3023         T(YAFFS_TRACE_ERROR,
3024                         (TSTR("!!!!!!!!! Allocator out !!!!!!!!!!!!!!!!!" TENDSTR)));
3025
3026         return -1;
3027 }
3028
3029 static int yaffs_GetErasedChunks(yaffs_Device *dev)
3030 {
3031         int n;
3032
3033         n = dev->nErasedBlocks * dev->nChunksPerBlock;
3034
3035         if (dev->allocationBlock > 0)
3036                 n += (dev->nChunksPerBlock - dev->allocationPage);
3037
3038         return n;
3039
3040 }
3041
3042 /*
3043  * yaffs_SkipRestOfBlock() skips over the rest of the allocation block
3044  * if we don't want to write to it.
3045  */
3046 static void yaffs_SkipRestOfBlock(yaffs_Device *dev)
3047 {
3048         if(dev->allocationBlock > 0){
3049                 yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, dev->allocationBlock);
3050                 if(bi->blockState == YAFFS_BLOCK_STATE_ALLOCATING){
3051                         bi->blockState = YAFFS_BLOCK_STATE_FULL;
3052                         dev->allocationBlock = -1;
3053                 }
3054         }
3055 }
3056
3057
3058 static int yaffs_GarbageCollectBlock(yaffs_Device *dev, int block,
3059                 int wholeBlock)
3060 {
3061         int oldChunk;
3062         int newChunk;
3063         int markNAND;
3064         int retVal = YAFFS_OK;
3065         int cleanups = 0;
3066         int i;
3067         int isCheckpointBlock;
3068         int matchingChunk;
3069         int maxCopies;
3070
3071         int chunksBefore = yaffs_GetErasedChunks(dev);
3072         int chunksAfter;
3073
3074         yaffs_ExtendedTags tags;
3075
3076         yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, block);
3077
3078         yaffs_Object *object;
3079
3080         isCheckpointBlock = (bi->blockState == YAFFS_BLOCK_STATE_CHECKPOINT);
3081
3082
3083         T(YAFFS_TRACE_TRACING,
3084                         (TSTR("Collecting block %d, in use %d, shrink %d, wholeBlock %d" TENDSTR),
3085                          block,
3086                          bi->pagesInUse,
3087                          bi->hasShrinkHeader,
3088                          wholeBlock));
3089
3090         /*yaffs_VerifyFreeChunks(dev); */
3091
3092         if(bi->blockState == YAFFS_BLOCK_STATE_FULL)
3093                 bi->blockState = YAFFS_BLOCK_STATE_COLLECTING;
3094         
3095         bi->hasShrinkHeader = 0;        /* clear the flag so that the block can erase */
3096
3097         /* Take off the number of soft deleted entries because
3098          * they're going to get really deleted during GC.
3099          */
3100         if(dev->gcChunk == 0) /* first time through for this block */
3101                 dev->nFreeChunks -= bi->softDeletions;
3102
3103         dev->isDoingGC = 1;
3104
3105         if (isCheckpointBlock ||
3106                         !yaffs_StillSomeChunkBits(dev, block)) {
3107                 T(YAFFS_TRACE_TRACING,
3108                                 (TSTR
3109                                  ("Collecting block %d that has no chunks in use" TENDSTR),
3110                                  block));
3111                 yaffs_BlockBecameDirty(dev, block);
3112         } else {
3113
3114                 __u8 *buffer = yaffs_GetTempBuffer(dev, __LINE__);
3115
3116                 yaffs_VerifyBlock(dev, bi, block);
3117
3118                 maxCopies = (wholeBlock) ? dev->nChunksPerBlock : 10;
3119                 oldChunk = block * dev->nChunksPerBlock + dev->gcChunk;
3120
3121                 for (/* init already done */;
3122                      retVal == YAFFS_OK &&
3123                      dev->gcChunk < dev->nChunksPerBlock &&
3124                      (bi->blockState == YAFFS_BLOCK_STATE_COLLECTING) &&
3125                      maxCopies > 0;
3126                      dev->gcChunk++, oldChunk++) {
3127                         if (yaffs_CheckChunkBit(dev, block, dev->gcChunk)) {
3128
3129                                 /* This page is in use and might need to be copied off */
3130
3131                                 maxCopies--;
3132
3133                                 markNAND = 1;
3134
3135                                 yaffs_InitialiseTags(&tags);
3136
3137                                 yaffs_ReadChunkWithTagsFromNAND(dev, oldChunk,
3138                                                                 buffer, &tags);
3139
3140                                 object =
3141                                     yaffs_FindObjectByNumber(dev,
3142                                                              tags.objectId);
3143
3144                                 T(YAFFS_TRACE_GC_DETAIL,
3145                                   (TSTR
3146                                    ("Collecting chunk in block %d, %d %d %d " TENDSTR),
3147                                    dev->gcChunk, tags.objectId, tags.chunkId,
3148                                    tags.byteCount));
3149
3150                                 if (object && !yaffs_SkipVerification(dev)) {
3151                                         if (tags.chunkId == 0)
3152                                                 matchingChunk = object->hdrChunk;
3153                                         else if (object->softDeleted)
3154                                                 matchingChunk = oldChunk; /* Defeat the test */
3155                                         else
3156                                                 matchingChunk = yaffs_FindChunkInFile(object, tags.chunkId, NULL);
3157
3158                                         if (oldChunk != matchingChunk)
3159                                                 T(YAFFS_TRACE_ERROR,
3160                                                   (TSTR("gc: page in gc mismatch: %d %d %d %d"TENDSTR),
3161                                                   oldChunk, matchingChunk, tags.objectId, tags.chunkId));
3162
3163                                 }
3164
3165                                 if (!object) {
3166                                         T(YAFFS_TRACE_ERROR,
3167                                           (TSTR
3168                                            ("page %d in gc has no object: %d %d %d "
3169                                             TENDSTR), oldChunk,
3170                                             tags.objectId, tags.chunkId, tags.byteCount));
3171                                 }
3172
3173                                 if (object &&
3174                                     object->deleted &&
3175                                     object->softDeleted &&
3176                                     tags.chunkId != 0) {
3177                                         /* Data chunk in a soft deleted file, throw it away
3178                                          * It's a soft deleted data chunk,
3179                                          * No need to copy this, just forget about it and
3180                                          * fix up the object.
3181                                          */
3182
3183                                         object->nDataChunks--;
3184
3185                                         if (object->nDataChunks <= 0) {
3186                                                 /* remeber to clean up the object */
3187                                                 dev->gcCleanupList[cleanups] =
3188                                                     tags.objectId;
3189                                                 cleanups++;
3190                                         }
3191                                         markNAND = 0;
3192                                 } else if (0) {
3193                                         /* Todo object && object->deleted && object->nDataChunks == 0 */
3194                                         /* Deleted object header with no data chunks.
3195                                          * Can be discarded and the file deleted.
3196                                          */
3197                                         object->hdrChunk = 0;
3198                                         yaffs_FreeTnode(object->myDev,
3199                                                         object->variant.
3200                                                         fileVariant.top);
3201                                         object->variant.fileVariant.top = NULL;
3202                                         yaffs_DoGenericObjectDeletion(object);
3203
3204                                 } else if (object) {
3205                                         /* It's either a data chunk in a live file or
3206                                          * an ObjectHeader, so we're interested in it.
3207                                          * NB Need to keep the ObjectHeaders of deleted files
3208                                          * until the whole file has been deleted off
3209                                          */
3210                                         tags.serialNumber++;
3211
3212                                         dev->nGCCopies++;
3213
3214                                         if (tags.chunkId == 0) {
3215                                                 /* It is an object Id,
3216                                                  * We need to nuke the shrinkheader flags first
3217                                                  * Also need to clean up shadowing.
3218                                                  * We no longer want the shrinkHeader flag since its work is done
3219                                                  * and if it is left in place it will mess up scanning.
3220                                                  */
3221
3222                                                 yaffs_ObjectHeader *oh;
3223                                                 oh = (yaffs_ObjectHeader *)buffer;
3224                                                 oh->isShrink = 0;
3225                                                 tags.extraIsShrinkHeader = 0;
3226                                                 oh->shadowsObject = 0;
3227                                                 oh->inbandShadowsObject = 0;
3228                                                 tags.extraShadows = 0;
3229
3230                                                 yaffs_VerifyObjectHeader(object, oh, &tags, 1);
3231                                         }
3232
3233                                         newChunk =
3234                                             yaffs_WriteNewChunkWithTagsToNAND(dev, buffer, &tags, 1);
3235
3236                                         if (newChunk < 0) {
3237                                                 retVal = YAFFS_FAIL;
3238                                         } else {
3239
3240                                                 /* Ok, now fix up the Tnodes etc. */
3241
3242                                                 if (tags.chunkId == 0) {
3243                                                         /* It's a header */
3244                                                         object->hdrChunk =  newChunk;
3245                                                         object->serial =   tags.serialNumber;
3246                                                 } else {
3247                                                         /* It's a data chunk */
3248                                                         yaffs_PutChunkIntoFile
3249                                                             (object,
3250                                                              tags.chunkId,
3251                                                              newChunk, 0);
3252                                                 }
3253                                         }
3254                                 }
3255
3256                                 if (retVal == YAFFS_OK)
3257                                         yaffs_DeleteChunk(dev, oldChunk, markNAND, __LINE__);
3258
3259                         }
3260                 }
3261
3262                 yaffs_ReleaseTempBuffer(dev, buffer, __LINE__);
3263
3264
3265                 /* Do any required cleanups */
3266                 for (i = 0; i < cleanups; i++) {
3267                         /* Time to delete the file too */
3268                         object =
3269                             yaffs_FindObjectByNumber(dev,
3270                                                      dev->gcCleanupList[i]);
3271                         if (object) {
3272                                 yaffs_FreeTnode(dev,
3273                                                 object->variant.fileVariant.
3274                                                 top);
3275                                 object->variant.fileVariant.top = NULL;
3276                                 T(YAFFS_TRACE_GC,
3277                                   (TSTR
3278                                    ("yaffs: About to finally delete object %d"
3279                                     TENDSTR), object->objectId));
3280                                 yaffs_DoGenericObjectDeletion(object);
3281                                 object->myDev->nDeletedFiles--;
3282                         }
3283
3284                 }
3285
3286         }
3287
3288         yaffs_VerifyCollectedBlock(dev, bi, block);
3289
3290         chunksAfter = yaffs_GetErasedChunks(dev);
3291         if (chunksBefore >= chunksAfter) {
3292                 T(YAFFS_TRACE_GC,
3293                   (TSTR
3294                    ("gc did not increase free chunks before %d after %d"
3295                     TENDSTR), chunksBefore, chunksAfter));
3296         }
3297
3298         /* If the gc completed then clear the current gcBlock so that we find another. */
3299         if (bi->blockState != YAFFS_BLOCK_STATE_COLLECTING) {
3300                 dev->gcBlock = -1;
3301                 dev->gcChunk = 0;
3302         }
3303
3304         dev->isDoingGC = 0;
3305
3306         return retVal;
3307 }
3308
3309 /* New garbage collector
3310  * If we're very low on erased blocks then we do aggressive garbage collection
3311  * otherwise we do "leasurely" garbage collection.
3312  * Aggressive gc looks further (whole array) and will accept less dirty blocks.
3313  * Passive gc only inspects smaller areas and will only accept more dirty blocks.
3314  *
3315  * The idea is to help clear out space in a more spread-out manner.
3316  * Dunno if it really does anything useful.
3317  */
3318 static int yaffs_CheckGarbageCollection(yaffs_Device *dev)
3319 {
3320         int block;
3321         int aggressive;
3322         int gcOk = YAFFS_OK;
3323         int maxTries = 0;
3324
3325         int checkpointBlockAdjust;
3326
3327         if (dev->isDoingGC) {
3328                 /* Bail out so we don't get recursive gc */
3329                 return YAFFS_OK;
3330         }
3331
3332         /* This loop should pass the first time.
3333          * We'll only see looping here if the erase of the collected block fails.
3334          */
3335
3336         do {
3337                 maxTries++;
3338
3339                 checkpointBlockAdjust = yaffs_CalcCheckpointBlocksRequired(dev) - dev->blocksInCheckpoint;
3340                 if (checkpointBlockAdjust < 0)
3341                         checkpointBlockAdjust = 0;
3342
3343                 if (dev->nErasedBlocks < (dev->nReservedBlocks + checkpointBlockAdjust + 2)) {
3344                         /* We need a block soon...*/
3345                         aggressive = 1;
3346                 } else {
3347                         /* We're in no hurry */
3348                         aggressive = 0;
3349                 }
3350
3351                 if (dev->gcBlock <