yaffs_guts.c

   1 /*
   2  * YAFFS: Yet another FFS. A NAND-flash specific file system.
   3  *
   4  * Copyright (C) 2002 Aleph One Ltd.
   5  *   for Toby Churchill Ltd and Brightstar Engineering
   6  *
   7  * Created by Charles Manning <charles@aleph1.co.uk>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2 as
  11  * published by the Free Software Foundation.
  12  *
  13  */
  14
  15 const char *yaffs_guts_c_version =
  16     "$Id: yaffs_guts.c,v 1.40 2006-10-13 08:52:49 charles Exp $";
  17
  18 #include "yportenv.h"
  19
  20 #include "yaffsinterface.h"
  21 #include "yaffs_guts.h"
  22 #include "yaffs_tagsvalidity.h"
  23
  24 #include "yaffs_tagscompat.h"
  25 #ifndef CONFIG_YAFFS_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 #ifdef CONFIG_YAFFS_WINCE
  37 void yfsd_LockYAFFS(BOOL fsLockOnly);
  38 void yfsd_UnlockYAFFS(BOOL fsLockOnly);
  39 #endif
  40
  41 #define YAFFS_PASSIVE_GC_CHUNKS 2
  42
  43 #include "yaffs_ecc.h"
  44
  45
  46 /* Robustification (if it ever comes about...) */
  47 static void yaffs_RetireBlock(yaffs_Device * dev, int blockInNAND);
  48 static void yaffs_HandleWriteChunkError(yaffs_Device * dev, int chunkInNAND, int erasedOk);
  49 static void yaffs_HandleWriteChunkOk(yaffs_Device * dev, int chunkInNAND,
  50                                      const __u8 * data,
  51                                      const yaffs_ExtendedTags * tags);
  52 static void yaffs_HandleUpdateChunk(yaffs_Device * dev, int chunkInNAND,
  53                                     const yaffs_ExtendedTags * tags);
  54
  55 /* Other local prototypes */
  56 static int yaffs_UnlinkObject( yaffs_Object *obj);
  57 static int yaffs_ObjectHasCachedWriteData(yaffs_Object *obj);
  58
  59 static void yaffs_HardlinkFixup(yaffs_Device *dev, yaffs_Object *hardList);
  60
  61 static int yaffs_WriteNewChunkWithTagsToNAND(yaffs_Device * dev,
  62                                              const __u8 * buffer,
  63                                              yaffs_ExtendedTags * tags,
  64                                              int useReserve);
  65 static int yaffs_PutChunkIntoFile(yaffs_Object * in, int chunkInInode,
  66                                   int chunkInNAND, int inScan);
  67
  68 static yaffs_Object *yaffs_CreateNewObject(yaffs_Device * dev, int number,
  69                                            yaffs_ObjectType type);
  70 static void yaffs_AddObjectToDirectory(yaffs_Object * directory,
  71                                        yaffs_Object * obj);
  72 static int yaffs_UpdateObjectHeader(yaffs_Object * in, const YCHAR * name,
  73                                     int force, int isShrink, int shadows);
  74 static void yaffs_RemoveObjectFromDirectory(yaffs_Object * obj);
  75 static int yaffs_CheckStructures(void);
  76 static int yaffs_DeleteWorker(yaffs_Object * in, yaffs_Tnode * tn, __u32 level,
  77                               int chunkOffset, int *limit);
  78 static int yaffs_DoGenericObjectDeletion(yaffs_Object * in);
  79
  80 static yaffs_BlockInfo *yaffs_GetBlockInfo(yaffs_Device * dev, int blockNo);
  81
  82 static __u8 *yaffs_GetTempBuffer(yaffs_Device * dev, int lineNo);
  83 static void yaffs_ReleaseTempBuffer(yaffs_Device * dev, __u8 * buffer,
  84                                     int lineNo);
  85
  86 static int yaffs_CheckChunkErased(struct yaffs_DeviceStruct *dev,
  87                                   int chunkInNAND);
  88
  89 static int yaffs_UnlinkWorker(yaffs_Object * obj);
  90 static void yaffs_DestroyObject(yaffs_Object * obj);
  91
  92 static int yaffs_TagsMatch(const yaffs_ExtendedTags * tags, int objectId,
  93                            int chunkInObject);
  94
  95 loff_t yaffs_GetFileSize(yaffs_Object * obj);
  96
  97 static int yaffs_AllocateChunk(yaffs_Device * dev, int useReserve, yaffs_BlockInfo **blockUsedPtr);
  98
  99 static void yaffs_VerifyFreeChunks(yaffs_Device * dev);
 100
 101 #ifdef YAFFS_PARANOID
 102 static int yaffs_CheckFileSanity(yaffs_Object * in);
 103 #else
 104 #define yaffs_CheckFileSanity(in)
 105 #endif
 106
 107 static void yaffs_InvalidateWholeChunkCache(yaffs_Object * in);
 108 static void yaffs_InvalidateChunkCache(yaffs_Object * object, int chunkId);
 109
 110 static void yaffs_InvalidateCheckpoint(yaffs_Device *dev);
 111
 112
 113
 114 /* Function to calculate chunk and offset */
 115
 116 static void yaffs_AddrToChunk(yaffs_Device *dev, loff_t addr, __u32 *chunk, __u32 *offset)
 117 {
 118         if(dev->chunkShift){
 119                 /* Easy-peasy power of 2 case */
 120                 *chunk  = (__u32)(addr >> dev->chunkShift);
 121                 *offset = (__u32)(addr & dev->chunkMask);
 122         }
 123         else if(dev->crumbsPerChunk)
 124         {
 125                 /* Case where we're using "crumbs" */
 126                 *offset = (__u32)(addr & dev->crumbMask);
 127                 addr >>= dev->crumbShift;
 128                 *chunk = ((__u32)addr)/dev->crumbsPerChunk;
 129                 *offset += ((addr - (*chunk * dev->crumbsPerChunk)) << dev->crumbShift);
 130         }
 131         else
 132                 YBUG();
 133 }
 134
 135 /* Function to return the number of shifts for a power of 2 greater than or equal
 136  * to the given number
 137  * Note we don't try to cater for all possible numbers and this does not have to
 138  * be hellishly efficient.
 139  */
 140
 141 static __u32 ShiftsGE(__u32 x)
 142 {
 143         int extraBits;
 144         int nShifts;
 145
 146         nShifts = extraBits = 0;
 147
 148         while(x>1){
 149                 if(x & 1) extraBits++;
 150                 x>>=1;
 151                 nShifts++;
 152         }
 153
 154         if(extraBits)
 155                 nShifts++;
 156
 157         return nShifts;
 158 }
 159
 160 /* Function to return the number of shifts to get a 1 in bit 0
 161  */
 162
 163 static __u32 ShiftDiv(__u32 x)
 164 {
 165         int nShifts;
 166
 167         nShifts =  0;
 168
 169         if(!x) return 0;
 170
 171         while( !(x&1)){
 172                 x>>=1;
 173                 nShifts++;
 174         }
 175
 176         return nShifts;
 177 }
 178
 179
 180
 181 /*
 182  * Temporary buffer manipulations.
 183  */
 184
 185 static __u8 *yaffs_GetTempBuffer(yaffs_Device * dev, int lineNo)
 186 {
 187         int i, j;
 188         for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
 189                 if (dev->tempBuffer[i].line == 0) {
 190                         dev->tempBuffer[i].line = lineNo;
 191                         if ((i + 1) > dev->maxTemp) {
 192                                 dev->maxTemp = i + 1;
 193                                 for (j = 0; j <= i; j++)
 194                                         dev->tempBuffer[j].maxLine =
 195                                             dev->tempBuffer[j].line;
 196                         }
 197
 198                         return dev->tempBuffer[i].buffer;
 199                 }
 200         }
 201
 202         T(YAFFS_TRACE_BUFFERS,
 203           (TSTR("Out of temp buffers at line %d, other held by lines:"),
 204            lineNo));
 205         for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
 206                 T(YAFFS_TRACE_BUFFERS, (TSTR(" %d "), dev->tempBuffer[i].line));
 207         }
 208         T(YAFFS_TRACE_BUFFERS, (TSTR(" " TENDSTR)));
 209
 210         /*
 211          * If we got here then we have to allocate an unmanaged one
 212          * This is not good.
 213          */
 214
 215         dev->unmanagedTempAllocations++;
 216         return YMALLOC(dev->nDataBytesPerChunk);
 217
 218 }
 219
 220 static void yaffs_ReleaseTempBuffer(yaffs_Device * dev, __u8 * buffer,
 221                                     int lineNo)
 222 {
 223         int i;
 224         for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
 225                 if (dev->tempBuffer[i].buffer == buffer) {
 226                         dev->tempBuffer[i].line = 0;
 227                         return;
 228                 }
 229         }
 230
 231         if (buffer) {
 232                 /* assume it is an unmanaged one. */
 233                 T(YAFFS_TRACE_BUFFERS,
 234                   (TSTR("Releasing unmanaged temp buffer in line %d" TENDSTR),
 235                    lineNo));
 236                 YFREE(buffer);
 237                 dev->unmanagedTempDeallocations++;
 238         }
 239
 240 }
 241
 242 /*
 243  * Determine if we have a managed buffer.
 244  */
 245 int yaffs_IsManagedTempBuffer(yaffs_Device * dev, const __u8 * buffer)
 246 {
 247         int i;
 248         for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
 249                 if (dev->tempBuffer[i].buffer == buffer)
 250                         return 1;
 251
 252         }
 253
 254     for (i = 0; i < dev->nShortOpCaches; i++) {
 255         if( dev->srCache[i].data == buffer )
 256             return 1;
 257
 258     }
 259
 260     if (buffer == dev->checkpointBuffer)
 261       return 1;
 262
 263     T(YAFFS_TRACE_ALWAYS,
 264           (TSTR("yaffs: unmaged buffer detected.\n" TENDSTR)));
 265     return 0;
 266 }
 267
 268 /*
 269  * Chunk bitmap manipulations
 270  */
 271
 272 static Y_INLINE __u8 *yaffs_BlockBits(yaffs_Device * dev, int blk)
 273 {
 274         if (blk < dev->internalStartBlock || blk > dev->internalEndBlock) {
 275                 T(YAFFS_TRACE_ERROR,
 276                   (TSTR("**>> yaffs: BlockBits block %d is not valid" TENDSTR),
 277                    blk));
 278                 YBUG();
 279         }
 280         return dev->chunkBits +
 281             (dev->chunkBitmapStride * (blk - dev->internalStartBlock));
 282 }
 283
 284 static Y_INLINE void yaffs_ClearChunkBits(yaffs_Device * dev, int blk)
 285 {
 286         __u8 *blkBits = yaffs_BlockBits(dev, blk);
 287
 288         memset(blkBits, 0, dev->chunkBitmapStride);
 289 }
 290
 291 static Y_INLINE void yaffs_ClearChunkBit(yaffs_Device * dev, int blk, int chunk)
 292 {
 293         __u8 *blkBits = yaffs_BlockBits(dev, blk);
 294
 295         blkBits[chunk / 8] &= ~(1 << (chunk & 7));
 296 }
 297
 298 static Y_INLINE void yaffs_SetChunkBit(yaffs_Device * dev, int blk, int chunk)
 299 {
 300         __u8 *blkBits = yaffs_BlockBits(dev, blk);
 301
 302         blkBits[chunk / 8] |= (1 << (chunk & 7));
 303 }
 304
 305 static Y_INLINE int yaffs_CheckChunkBit(yaffs_Device * dev, int blk, int chunk)
 306 {
 307         __u8 *blkBits = yaffs_BlockBits(dev, blk);
 308         return (blkBits[chunk / 8] & (1 << (chunk & 7))) ? 1 : 0;
 309 }
 310
 311 static Y_INLINE int yaffs_StillSomeChunkBits(yaffs_Device * dev, int blk)
 312 {
 313         __u8 *blkBits = yaffs_BlockBits(dev, blk);
 314         int i;
 315         for (i = 0; i < dev->chunkBitmapStride; i++) {
 316                 if (*blkBits)
 317                         return 1;
 318                 blkBits++;
 319         }
 320         return 0;
 321 }
 322
 323 /*
 324  *  Simple hash function. Needs to have a reasonable spread
 325  */
 326
 327 static Y_INLINE int yaffs_HashFunction(int n)
 328 {
 329         n = abs(n);
 330         return (n % YAFFS_NOBJECT_BUCKETS);
 331 }
 332
 333 /*
 334  * Access functions to useful fake objects
 335  */
 336
 337 yaffs_Object *yaffs_Root(yaffs_Device * dev)
 338 {
 339         return dev->rootDir;
 340 }
 341
 342 yaffs_Object *yaffs_LostNFound(yaffs_Device * dev)
 343 {
 344         return dev->lostNFoundDir;
 345 }
 346
 347
 348 /*
 349  *  Erased NAND checking functions
 350  */
 351
 352 int yaffs_CheckFF(__u8 * buffer, int nBytes)
 353 {
 354         /* Horrible, slow implementation */
 355         while (nBytes--) {
 356                 if (*buffer != 0xFF)
 357                         return 0;
 358                 buffer++;
 359         }
 360         return 1;
 361 }
 362
 363 static int yaffs_CheckChunkErased(struct yaffs_DeviceStruct *dev,
 364                                   int chunkInNAND)
 365 {
 366
 367         int retval = YAFFS_OK;
 368         __u8 *data = yaffs_GetTempBuffer(dev, __LINE__);
 369         yaffs_ExtendedTags tags;
 370         int result;
 371
 372         result = yaffs_ReadChunkWithTagsFromNAND(dev, chunkInNAND, data, &tags);
 373
 374         if(tags.eccResult > YAFFS_ECC_RESULT_NO_ERROR)
 375                 retval = YAFFS_FAIL;
 376
 377
 378         if (!yaffs_CheckFF(data, dev->nDataBytesPerChunk) || tags.chunkUsed) {
 379                 T(YAFFS_TRACE_NANDACCESS,
 380                   (TSTR("Chunk %d not erased" TENDSTR), chunkInNAND));
 381                 retval = YAFFS_FAIL;
 382         }
 383
 384         yaffs_ReleaseTempBuffer(dev, data, __LINE__);
 385
 386         return retval;
 387
 388 }
 389
 390 static int yaffs_WriteNewChunkWithTagsToNAND(struct yaffs_DeviceStruct *dev,
 391                                              const __u8 * data,
 392                                              yaffs_ExtendedTags * tags,
 393                                              int useReserve)
 394 {
 395         int chunk;
 396
 397         int writeOk = 0;
 398         int erasedOk = 1;
 399         int attempts = 0;
 400         yaffs_BlockInfo *bi;
 401
 402         yaffs_InvalidateCheckpoint(dev);
 403
 404         do {
 405                 chunk = yaffs_AllocateChunk(dev, useReserve,&bi);
 406
 407                 if (chunk >= 0) {
 408                         /* First check this chunk is erased, if it needs checking.
 409                          * The checking policy (unless forced always on) is as follows:
 410                          * Check the first page we try to write in a block.
 411                          * - If the check passes then we don't need to check any more.
 412                          * - If the check fails, we check again...
 413                          * If the block has been erased, we don't need to check.
 414                          *
 415                          * However, if the block has been prioritised for gc, then
 416                          * we think there might be something odd about this block
 417                          * and stop using it.
 418                          *
 419                          * Rationale:
 420                          * We should only ever see chunks that have not been erased
 421                          * if there was a partially written chunk due to power loss
 422                          * This checking policy should catch that case with very
 423                          * few checks and thus save a lot of checks that are most likely not
 424                          * needed.
 425                          */
 426
 427                          if(bi->gcPrioritise){
 428                                         yaffs_DeleteChunk(dev, chunk, 1, __LINE__);
 429                         } else {
 430 #ifdef CONFIG_YAFFS_ALWAYS_CHECK_CHUNK_ERASED
 431
 432                                 bi->skipErasedCheck = 0;
 433
 434 #endif
 435                                 if(!bi->skipErasedCheck){
 436                                         erasedOk = yaffs_CheckChunkErased(dev, chunk);
 437                                         if(erasedOk && !bi->gcPrioritise)
 438                                                 bi->skipErasedCheck = 1;
 439                                 }
 440
 441                                 if (!erasedOk) {
 442                                         T(YAFFS_TRACE_ERROR,
 443                                           (TSTR
 444                                            ("**>> yaffs chunk %d was not erased"
 445                                             TENDSTR), chunk));
 446                                 } else {
 447                                         writeOk =
 448                                             yaffs_WriteChunkWithTagsToNAND(dev, chunk,
 449                                                                            data, tags);
 450                                 }
 451
 452                                 attempts++;
 453
 454                                 if (writeOk) {
 455                                         /*
 456                                          *  Copy the data into the robustification buffer.
 457                                          *  NB We do this at the end to prevent duplicates in the case of a write error.
 458                                          *  Todo
 459                                          */
 460                                         yaffs_HandleWriteChunkOk(dev, chunk, data, tags);
 461
 462                                 } else {
 463                                         /* The erased check or write failed */
 464                                         yaffs_HandleWriteChunkError(dev, chunk, erasedOk);
 465                                 }
 466                         }
 467                 }
 468
 469         } while (chunk >= 0 && !writeOk);
 470
 471         if (attempts > 1) {
 472                 T(YAFFS_TRACE_ERROR,
 473                   (TSTR("**>> yaffs write required %d attempts" TENDSTR),
 474                    attempts));
 475                 dev->nRetriedWrites += (attempts - 1);
 476         }
 477
 478         return chunk;
 479 }
 480
 481 /*
 482  * Block retiring for handling a broken block.
 483  */
 484
 485 static void yaffs_RetireBlock(yaffs_Device * dev, int blockInNAND)
 486 {
 487
 488         yaffs_InvalidateCheckpoint(dev);
 489
 490         yaffs_MarkBlockBad(dev, blockInNAND);
 491
 492         yaffs_GetBlockInfo(dev, blockInNAND)->blockState =
 493             YAFFS_BLOCK_STATE_DEAD;
 494
 495         dev->nRetiredBlocks++;
 496 }
 497
 498 /*
 499  * Functions for robustisizing TODO
 500  *
 501  */
 502
 503 static void yaffs_HandleWriteChunkOk(yaffs_Device * dev, int chunkInNAND,
 504                                      const __u8 * data,
 505                                      const yaffs_ExtendedTags * tags)
 506 {
 507 }
 508
 509 static void yaffs_HandleUpdateChunk(yaffs_Device * dev, int chunkInNAND,
 510                                     const yaffs_ExtendedTags * tags)
 511 {
 512 }
 513
 514 void yaffs_HandleChunkError(yaffs_Device *dev, yaffs_BlockInfo *bi)
 515 {
 516         if(!bi->gcPrioritise){
 517                 bi->gcPrioritise = 1;
 518                 dev->hasPendingPrioritisedGCs = 1;
 519                 bi->chunkErrorStrikes ++;
 520
 521                 if(bi->chunkErrorStrikes > 3){
 522                         bi->needsRetiring = 1; /* Too many stikes, so retire this */
 523                         T(YAFFS_TRACE_ALWAYS, (TSTR("yaffs: Block struck out" TENDSTR)));
 524
 525                 }
 526
 527         }
 528 }
 529
 530 static void yaffs_HandleWriteChunkError(yaffs_Device * dev, int chunkInNAND, int erasedOk)
 531 {
 532
 533         int blockInNAND = chunkInNAND / dev->nChunksPerBlock;
 534         yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, blockInNAND);
 535
 536         yaffs_HandleChunkError(dev,bi);
 537
 538
 539         if(erasedOk ) {
 540                 /* Was an actual write failure, so mark the block for retirement  */
 541                 bi->needsRetiring = 1;
 542
 543         }
 544
 545         /* Delete the chunk */
 546         yaffs_DeleteChunk(dev, chunkInNAND, 1, __LINE__);
 547 }
 548
 549
 550 /*---------------- Name handling functions ------------*/
 551
 552 static __u16 yaffs_CalcNameSum(const YCHAR * name)
 553 {
 554         __u16 sum = 0;
 555         __u16 i = 1;
 556
 557         YUCHAR *bname = (YUCHAR *) name;
 558         if (bname) {
 559                 while ((*bname) && (i <= YAFFS_MAX_NAME_LENGTH)) {
 560
 561 #ifdef CONFIG_YAFFS_CASE_INSENSITIVE
 562                         sum += yaffs_toupper(*bname) * i;
 563 #else
 564                         sum += (*bname) * i;
 565 #endif
 566                         i++;
 567                         bname++;
 568                 }
 569         }
 570         return sum;
 571 }
 572
 573 static void yaffs_SetObjectName(yaffs_Object * obj, const YCHAR * name)
 574 {
 575 #ifdef CONFIG_YAFFS_SHORT_NAMES_IN_RAM
 576         if (name && yaffs_strlen(name) <= YAFFS_SHORT_NAME_LENGTH) {
 577                 yaffs_strcpy(obj->shortName, name);
 578         } else {
 579                 obj->shortName[0] = _Y('\0');
 580         }
 581 #endif
 582         obj->sum = yaffs_CalcNameSum(name);
 583 }
 584
 585 /*-------------------- TNODES -------------------
 586
 587  * List of spare tnodes
 588  * The list is hooked together using the first pointer
 589  * in the tnode.
 590  */
 591
 592 /* yaffs_CreateTnodes creates a bunch more tnodes and
 593  * adds them to the tnode free list.
 594  * Don't use this function directly
 595  */
 596
 597 static int yaffs_CreateTnodes(yaffs_Device * dev, int nTnodes)
 598 {
 599         int i;
 600         int tnodeSize;
 601         yaffs_Tnode *newTnodes;
 602         __u8 *mem;
 603         yaffs_Tnode *curr;
 604         yaffs_Tnode *next;
 605         yaffs_TnodeList *tnl;
 606
 607         if (nTnodes < 1)
 608                 return YAFFS_OK;
 609
 610         /* Calculate the tnode size in bytes for variable width tnode support.
 611          * Must be a multiple of 32-bits  */
 612         tnodeSize = (dev->tnodeWidth * YAFFS_NTNODES_LEVEL0)/8;
 613
 614         /* make these things */
 615
 616         newTnodes = YMALLOC(nTnodes * tnodeSize);
 617         mem = (__u8 *)newTnodes;
 618
 619         if (!newTnodes) {
 620                 T(YAFFS_TRACE_ERROR,
 621                   (TSTR("yaffs: Could not allocate Tnodes" TENDSTR)));
 622                 return YAFFS_FAIL;
 623         }
 624
 625         /* Hook them into the free list */
 626 #if 0
 627         for (i = 0; i < nTnodes - 1; i++) {
 628                 newTnodes[i].internal[0] = &newTnodes[i + 1];
 629 #ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
 630                 newTnodes[i].internal[YAFFS_NTNODES_INTERNAL] = (void *)1;
 631 #endif
 632         }
 633
 634         newTnodes[nTnodes - 1].internal[0] = dev->freeTnodes;
 635 #ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
 636         newTnodes[nTnodes - 1].internal[YAFFS_NTNODES_INTERNAL] = (void *)1;
 637 #endif
 638         dev->freeTnodes = newTnodes;
 639 #else
 640         /* New hookup for wide tnodes */
 641         for(i = 0; i < nTnodes -1; i++) {
 642                 curr = (yaffs_Tnode *) &mem[i * tnodeSize];
 643                 next = (yaffs_Tnode *) &mem[(i+1) * tnodeSize];
 644                 curr->internal[0] = next;
 645         }
 646
 647         curr = (yaffs_Tnode *) &mem[(nTnodes - 1) * tnodeSize];
 648         curr->internal[0] = dev->freeTnodes;
 649         dev->freeTnodes = (yaffs_Tnode *)mem;
 650
 651 #endif
 652
 653
 654         dev->nFreeTnodes += nTnodes;
 655         dev->nTnodesCreated += nTnodes;
 656
 657         /* Now add this bunch of tnodes to a list for freeing up.
 658          * NB If we can't add this to the management list it isn't fatal
 659          * but it just means we can't free this bunch of tnodes later.
 660          */
 661
 662         tnl = YMALLOC(sizeof(yaffs_TnodeList));
 663         if (!tnl) {
 664                 T(YAFFS_TRACE_ERROR,
 665                   (TSTR
 666                    ("yaffs: Could not add tnodes to management list" TENDSTR)));
 667
 668         } else {
 669                 tnl->tnodes = newTnodes;
 670                 tnl->next = dev->allocatedTnodeList;
 671                 dev->allocatedTnodeList = tnl;
 672         }
 673
 674         T(YAFFS_TRACE_ALLOCATE, (TSTR("yaffs: Tnodes added" TENDSTR)));
 675
 676         return YAFFS_OK;
 677 }
 678
 679 /* GetTnode gets us a clean tnode. Tries to make allocate more if we run out */
 680
 681 static yaffs_Tnode *yaffs_GetTnodeRaw(yaffs_Device * dev)
 682 {
 683         yaffs_Tnode *tn = NULL;
 684
 685         /* If there are none left make more */
 686         if (!dev->freeTnodes) {
 687                 yaffs_CreateTnodes(dev, YAFFS_ALLOCATION_NTNODES);
 688         }
 689
 690         if (dev->freeTnodes) {
 691                 tn = dev->freeTnodes;
 692 #ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
 693                 if (tn->internal[YAFFS_NTNODES_INTERNAL] != (void *)1) {
 694                         /* Hoosterman, this thing looks like it isn't in the list */
 695                         T(YAFFS_TRACE_ALWAYS,
 696                           (TSTR("yaffs: Tnode list bug 1" TENDSTR)));
 697                 }
 698 #endif
 699                 dev->freeTnodes = dev->freeTnodes->internal[0];
 700                 dev->nFreeTnodes--;
 701         }
 702
 703         return tn;
 704 }
 705
 706 static yaffs_Tnode *yaffs_GetTnode(yaffs_Device * dev)
 707 {
 708         yaffs_Tnode *tn = yaffs_GetTnodeRaw(dev);
 709
 710         if(tn)
 711                 memset(tn, 0, (dev->tnodeWidth * YAFFS_NTNODES_LEVEL0)/8);
 712
 713         return tn;
 714 }
 715
 716 /* FreeTnode frees up a tnode and puts it back on the free list */
 717 static void yaffs_FreeTnode(yaffs_Device * dev, yaffs_Tnode * tn)
 718 {
 719         if (tn) {
 720 #ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
 721                 if (tn->internal[YAFFS_NTNODES_INTERNAL] != 0) {
 722                         /* Hoosterman, this thing looks like it is already in the list */
 723                         T(YAFFS_TRACE_ALWAYS,
 724                           (TSTR("yaffs: Tnode list bug 2" TENDSTR)));
 725                 }
 726                 tn->internal[YAFFS_NTNODES_INTERNAL] = (void *)1;
 727 #endif
 728                 tn->internal[0] = dev->freeTnodes;
 729                 dev->freeTnodes = tn;
 730                 dev->nFreeTnodes++;
 731         }
 732 }
 733
 734 static void yaffs_DeinitialiseTnodes(yaffs_Device * dev)
 735 {
 736         /* Free the list of allocated tnodes */
 737         yaffs_TnodeList *tmp;
 738
 739         while (dev->allocatedTnodeList) {
 740                 tmp = dev->allocatedTnodeList->next;
 741
 742                 YFREE(dev->allocatedTnodeList->tnodes);
 743                 YFREE(dev->allocatedTnodeList);
 744                 dev->allocatedTnodeList = tmp;
 745
 746         }
 747
 748         dev->freeTnodes = NULL;
 749         dev->nFreeTnodes = 0;
 750 }
 751
 752 static void yaffs_InitialiseTnodes(yaffs_Device * dev)
 753 {
 754         dev->allocatedTnodeList = NULL;
 755         dev->freeTnodes = NULL;
 756         dev->nFreeTnodes = 0;
 757         dev->nTnodesCreated = 0;
 758
 759 }
 760
 761
 762 void yaffs_PutLevel0Tnode(yaffs_Device *dev, yaffs_Tnode *tn, unsigned pos, unsigned val)
 763 {
 764   __u32 *map = (__u32 *)tn;
 765   __u32 bitInMap;
 766   __u32 bitInWord;
 767   __u32 wordInMap;
 768   __u32 mask;
 769
 770   pos &= YAFFS_TNODES_LEVEL0_MASK;
 771   val >>= dev->chunkGroupBits;
 772
 773   bitInMap = pos * dev->tnodeWidth;
 774   wordInMap = bitInMap /32;
 775   bitInWord = bitInMap & (32 -1);
 776
 777   mask = dev->tnodeMask << bitInWord;
 778
 779   map[wordInMap] &= ~mask;
 780   map[wordInMap] |= (mask & (val << bitInWord));
 781
 782   if(dev->tnodeWidth > (32-bitInWord)) {
 783     bitInWord = (32 - bitInWord);
 784     wordInMap++;;
 785     mask = dev->tnodeMask >> (/*dev->tnodeWidth -*/ bitInWord);
 786     map[wordInMap] &= ~mask;
 787     map[wordInMap] |= (mask & (val >> bitInWord));
 788   }
 789 }
 790
 791 __u32 yaffs_GetChunkGroupBase(yaffs_Device *dev, yaffs_Tnode *tn, unsigned pos)
 792 {
 793   __u32 *map = (__u32 *)tn;
 794   __u32 bitInMap;
 795   __u32 bitInWord;
 796   __u32 wordInMap;
 797   __u32 val;
 798
 799   pos &= YAFFS_TNODES_LEVEL0_MASK;
 800
 801   bitInMap = pos * dev->tnodeWidth;
 802   wordInMap = bitInMap /32;
 803   bitInWord = bitInMap & (32 -1);
 804
 805   val = map[wordInMap] >> bitInWord;
 806
 807   if(dev->tnodeWidth > (32-bitInWord)) {
 808     bitInWord = (32 - bitInWord);
 809     wordInMap++;;
 810     val |= (map[wordInMap] << bitInWord);
 811   }
 812
 813   val &= dev->tnodeMask;
 814   val <<= dev->chunkGroupBits;
 815
 816   return val;
 817 }
 818
 819 /* ------------------- End of individual tnode manipulation -----------------*/
 820
 821 /* ---------Functions to manipulate the look-up tree (made up of tnodes) ------
 822  * The look up tree is represented by the top tnode and the number of topLevel
 823  * in the tree. 0 means only the level 0 tnode is in the tree.
 824  */
 825
 826 /* FindLevel0Tnode finds the level 0 tnode, if one exists. */
 827 static yaffs_Tnode *yaffs_FindLevel0Tnode(yaffs_Device * dev,
 828                                           yaffs_FileStructure * fStruct,
 829                                           __u32 chunkId)
 830 {
 831
 832         yaffs_Tnode *tn = fStruct->top;
 833         __u32 i;
 834         int requiredTallness;
 835         int level = fStruct->topLevel;
 836
 837         /* Check sane level and chunk Id */
 838         if (level < 0 || level > YAFFS_TNODES_MAX_LEVEL) {
 839                 return NULL;
 840         }
 841
 842         if (chunkId > YAFFS_MAX_CHUNK_ID) {
 843                 return NULL;
 844         }
 845
 846         /* First check we're tall enough (ie enough topLevel) */
 847
 848         i = chunkId >> YAFFS_TNODES_LEVEL0_BITS;
 849         requiredTallness = 0;
 850         while (i) {
 851                 i >>= YAFFS_TNODES_INTERNAL_BITS;
 852                 requiredTallness++;
 853         }
 854
 855         if (requiredTallness > fStruct->topLevel) {
 856                 /* Not tall enough, so we can't find it, return NULL. */
 857                 return NULL;
 858         }
 859
 860         /* Traverse down to level 0 */
 861         while (level > 0 && tn) {
 862                 tn = tn->
 863                     internal[(chunkId >>
 864                                ( YAFFS_TNODES_LEVEL0_BITS +
 865                                  (level - 1) *
 866                                  YAFFS_TNODES_INTERNAL_BITS)
 867                               ) &
 868                              YAFFS_TNODES_INTERNAL_MASK];
 869                 level--;
 870
 871         }
 872
 873         return tn;
 874 }
 875
 876 /* AddOrFindLevel0Tnode finds the level 0 tnode if it exists, otherwise first expands the tree.
 877  * This happens in two steps:
 878  *  1. If the tree isn't tall enough, then make it taller.
 879  *  2. Scan down the tree towards the level 0 tnode adding tnodes if required.
 880  *
 881  * Used when modifying the tree.
 882  *
 883  *  If the tn argument is NULL, then a fresh tnode will be added otherwise the specified tn will
 884  *  be plugged into the ttree.
 885  */
 886
 887 static yaffs_Tnode *yaffs_AddOrFindLevel0Tnode(yaffs_Device * dev,
 888                                                yaffs_FileStructure * fStruct,
 889                                                __u32 chunkId,
 890                                                yaffs_Tnode *passedTn)
 891 {
 892
 893         int requiredTallness;
 894         int i;
 895         int l;
 896         yaffs_Tnode *tn;
 897
 898         __u32 x;
 899
 900
 901         /* Check sane level and page Id */
 902         if (fStruct->topLevel < 0 || fStruct->topLevel > YAFFS_TNODES_MAX_LEVEL) {
 903                 return NULL;
 904         }
 905
 906         if (chunkId > YAFFS_MAX_CHUNK_ID) {
 907                 return NULL;
 908         }
 909
 910         /* First check we're tall enough (ie enough topLevel) */
 911
 912         x = chunkId >> YAFFS_TNODES_LEVEL0_BITS;
 913         requiredTallness = 0;
 914         while (x) {
 915                 x >>= YAFFS_TNODES_INTERNAL_BITS;
 916                 requiredTallness++;
 917         }
 918
 919
 920         if (requiredTallness > fStruct->topLevel) {
 921                 /* Not tall enough,gotta make the tree taller */
 922                 for (i = fStruct->topLevel; i < requiredTallness; i++) {
 923
 924                         tn = yaffs_GetTnode(dev);
 925
 926                         if (tn) {
 927                                 tn->internal[0] = fStruct->top;
 928                                 fStruct->top = tn;
 929                         } else {
 930                                 T(YAFFS_TRACE_ERROR,
 931                                   (TSTR("yaffs: no more tnodes" TENDSTR)));
 932                         }
 933                 }
 934
 935                 fStruct->topLevel = requiredTallness;
 936         }
 937
 938         /* Traverse down to level 0, adding anything we need */
 939
 940         l = fStruct->topLevel;
 941         tn = fStruct->top;
 942
 943         if(l > 0) {
 944                 while (l > 0 && tn) {
 945                         x = (chunkId >>
 946                              ( YAFFS_TNODES_LEVEL0_BITS +
 947                               (l - 1) * YAFFS_TNODES_INTERNAL_BITS)) &
 948                             YAFFS_TNODES_INTERNAL_MASK;
 949
 950
 951                         if((l>1) && !tn->internal[x]){
 952                                 /* Add missing non-level-zero tnode */
 953                                 tn->internal[x] = yaffs_GetTnode(dev);
 954
 955                         } else if(l == 1) {
 956                                 /* Looking from level 1 at level 0 */
 957                                 if (passedTn) {
 958                                         /* If we already have one, then release it.*/
 959                                         if(tn->internal[x])
 960                                                 yaffs_FreeTnode(dev,tn->internal[x]);
 961                                         tn->internal[x] = passedTn;
 962
 963                                 } else if(!tn->internal[x]) {
 964                                         /* Don't have one, none passed in */
 965                                         tn->internal[x] = yaffs_GetTnode(dev);
 966                                 }
 967                         }
 968
 969                         tn = tn->internal[x];
 970                         l--;
 971                 }
 972         } else {
 973                 /* top is level 0 */
 974                 if(passedTn) {
 975                         memcpy(tn,passedTn,(dev->tnodeWidth * YAFFS_NTNODES_LEVEL0)/8);
 976                         yaffs_FreeTnode(dev,passedTn);
 977                 }
 978         }
 979
 980         return tn;
 981 }
 982
 983 static int yaffs_FindChunkInGroup(yaffs_Device * dev, int theChunk,
 984                                   yaffs_ExtendedTags * tags, int objectId,
 985                                   int chunkInInode)
 986 {
 987         int j;
 988
 989         for (j = 0; theChunk && j < dev->chunkGroupSize; j++) {
 990                 if (yaffs_CheckChunkBit
 991                     (dev, theChunk / dev->nChunksPerBlock,
 992                      theChunk % dev->nChunksPerBlock)) {
 993                         yaffs_ReadChunkWithTagsFromNAND(dev, theChunk, NULL,
 994                                                         tags);
 995                         if (yaffs_TagsMatch(tags, objectId, chunkInInode)) {
 996                                 /* found it; */
 997                                 return theChunk;
 998
 999                         }
1000                 }
1001                 theChunk++;
1002         }
1003         return -1;
1004 }
1005
1006
1007 /* DeleteWorker scans backwards through the tnode tree and deletes all the
1008  * chunks and tnodes in the file
1009  * Returns 1 if the tree was deleted.
1010  * Returns 0 if it stopped early due to hitting the limit and the delete is incomplete.
1011  */
1012
1013 static int yaffs_DeleteWorker(yaffs_Object * in, yaffs_Tnode * tn, __u32 level,
1014                               int chunkOffset, int *limit)
1015 {
1016         int i;
1017         int chunkInInode;
1018         int theChunk;
1019         yaffs_ExtendedTags tags;
1020         int foundChunk;
1021         yaffs_Device *dev = in->myDev;
1022
1023         int allDone = 1;
1024
1025         if (tn) {
1026                 if (level > 0) {
1027
1028                         for (i = YAFFS_NTNODES_INTERNAL - 1; allDone && i >= 0;
1029                              i--) {
1030                                 if (tn->internal[i]) {
1031                                         if (limit && (*limit) < 0) {
1032                                                 allDone = 0;
1033                                         } else {
1034                                                 allDone =
1035                                                     yaffs_DeleteWorker(in,
1036                                                                        tn->
1037                                                                        internal
1038                                                                        [i],
1039                                                                        level -
1040                                                                        1,
1041                                                                        (chunkOffset
1042                                                                         <<
1043                                                                         YAFFS_TNODES_INTERNAL_BITS)
1044                                                                        + i,
1045                                                                        limit);
1046                                         }
1047                                         if (allDone) {
1048                                                 yaffs_FreeTnode(dev,
1049                                                                 tn->
1050                                                                 internal[i]);
1051                                                 tn->internal[i] = NULL;
1052                                         }
1053                                 }
1054
1055                         }
1056                         return (allDone) ? 1 : 0;
1057                 } else if (level == 0) {
1058                         int hitLimit = 0;
1059
1060                         for (i = YAFFS_NTNODES_LEVEL0 - 1; i >= 0 && !hitLimit;
1061                              i--) {
1062                                 theChunk = yaffs_GetChunkGroupBase(dev,tn,i);
1063                                 if (theChunk) {
1064
1065                                         chunkInInode =
1066                                             (chunkOffset <<
1067                                              YAFFS_TNODES_LEVEL0_BITS) + i;
1068
1069                                         foundChunk =
1070                                             yaffs_FindChunkInGroup(dev,
1071                                                                    theChunk,
1072                                                                    &tags,
1073                                                                    in->objectId,
1074                                                                    chunkInInode);
1075
1076                                         if (foundChunk > 0) {
1077                                                 yaffs_DeleteChunk(dev,
1078                                                                   foundChunk, 1,
1079                                                                   __LINE__);
1080                                                 in->nDataChunks--;
1081                                                 if (limit) {
1082                                                         *limit = *limit - 1;
1083                                                         if (*limit <= 0) {
1084                                                                 hitLimit = 1;
1085                                                         }
1086                                                 }
1087
1088                                         }
1089
1090                                         yaffs_PutLevel0Tnode(dev,tn,i,0);
1091                                 }
1092
1093                         }
1094                         return (i < 0) ? 1 : 0;
1095
1096                 }
1097
1098         }
1099
1100         return 1;
1101
1102 }
1103
1104 static void yaffs_SoftDeleteChunk(yaffs_Device * dev, int chunk)
1105 {
1106
1107         yaffs_BlockInfo *theBlock;
1108
1109         T(YAFFS_TRACE_DELETION, (TSTR("soft delete chunk %d" TENDSTR), chunk));
1110
1111         theBlock = yaffs_GetBlockInfo(dev, chunk / dev->nChunksPerBlock);
1112         if (theBlock) {
1113                 theBlock->softDeletions++;
1114                 dev->nFreeChunks++;
1115         }
1116 }
1117
1118 /* SoftDeleteWorker scans backwards through the tnode tree and soft deletes all the chunks in the file.
1119  * All soft deleting does is increment the block's softdelete count and pulls the chunk out
1120  * of the tnode.
1121  * Thus, essentially this is the same as DeleteWorker except that the chunks are soft deleted.
1122  */
1123
1124 static int yaffs_SoftDeleteWorker(yaffs_Object * in, yaffs_Tnode * tn,
1125                                   __u32 level, int chunkOffset)
1126 {
1127         int i;
1128         int theChunk;
1129         int allDone = 1;
1130         yaffs_Device *dev = in->myDev;
1131
1132         if (tn) {
1133                 if (level > 0) {
1134
1135                         for (i = YAFFS_NTNODES_INTERNAL - 1; allDone && i >= 0;
1136                              i--) {
1137                                 if (tn->internal[i]) {
1138                                         allDone =
1139                                             yaffs_SoftDeleteWorker(in,
1140                                                                    tn->
1141                                                                    internal[i],
1142                                                                    level - 1,
1143                                                                    (chunkOffset
1144                                                                     <<
1145                                                                     YAFFS_TNODES_INTERNAL_BITS)
1146                                                                    + i);
1147                                         if (allDone) {
1148                                                 yaffs_FreeTnode(dev,
1149                                                                 tn->
1150                                                                 internal[i]);
1151                                                 tn->internal[i] = NULL;
1152                                         } else {
1153                                                 /* Hoosterman... how could this happen? */
1154                                         }
1155                                 }
1156                         }
1157                         return (allDone) ? 1 : 0;
1158                 } else if (level == 0) {
1159
1160                         for (i = YAFFS_NTNODES_LEVEL0 - 1; i >= 0; i--) {
1161                                 theChunk = yaffs_GetChunkGroupBase(dev,tn,i);
1162                                 if (theChunk) {
1163                                         /* Note this does not find the real chunk, only the chunk group.
1164                                          * We make an assumption that a chunk group is not larger than
1165                                          * a block.
1166                                          */
1167                                         yaffs_SoftDeleteChunk(dev, theChunk);
1168                                         yaffs_PutLevel0Tnode(dev,tn,i,0);
1169                                 }
1170
1171                         }
1172                         return 1;
1173
1174                 }
1175
1176         }
1177
1178         return 1;
1179
1180 }
1181
1182 static void yaffs_SoftDeleteFile(yaffs_Object * obj)
1183 {
1184         if (obj->deleted &&
1185             obj->variantType == YAFFS_OBJECT_TYPE_FILE && !obj->softDeleted) {
1186                 if (obj->nDataChunks <= 0) {
1187                         /* Empty file with no duplicate object headers, just delete it immediately */
1188                         yaffs_FreeTnode(obj->myDev,
1189                                         obj->variant.fileVariant.top);
1190                         obj->variant.fileVariant.top = NULL;
1191                         T(YAFFS_TRACE_TRACING,
1192                           (TSTR("yaffs: Deleting empty file %d" TENDSTR),
1193                            obj->objectId));
1194                         yaffs_DoGenericObjectDeletion(obj);
1195                 } else {
1196                         yaffs_SoftDeleteWorker(obj,
1197                                                obj->variant.fileVariant.top,
1198                                                obj->variant.fileVariant.
1199                                                topLevel, 0);
1200                         obj->softDeleted = 1;
1201                 }
1202         }
1203 }
1204
1205 /* Pruning removes any part of the file structure tree that is beyond the
1206  * bounds of the file (ie that does not point to chunks).
1207  *
1208  * A file should only get pruned when its size is reduced.
1209  *
1210  * Before pruning, the chunks must be pulled from the tree and the
1211  * level 0 tnode entries must be zeroed out.
1212  * Could also use this for file deletion, but that's probably better handled
1213  * by a special case.
1214  */
1215
1216 static yaffs_Tnode *yaffs_PruneWorker(yaffs_Device * dev, yaffs_Tnode * tn,
1217                                       __u32 level, int del0)
1218 {
1219         int i;
1220         int hasData;
1221
1222         if (tn) {
1223                 hasData = 0;
1224
1225                 for (i = 0; i < YAFFS_NTNODES_INTERNAL; i++) {
1226                         if (tn->internal[i] && level > 0) {
1227                                 tn->internal[i] =
1228                                     yaffs_PruneWorker(dev, tn->internal[i],
1229                                                       level - 1,
1230                                                       (i == 0) ? del0 : 1);
1231                         }
1232
1233                         if (tn->internal[i]) {
1234                                 hasData++;
1235                         }
1236                 }
1237
1238                 if (hasData == 0 && del0) {
1239                         /* Free and return NULL */
1240
1241                         yaffs_FreeTnode(dev, tn);
1242                         tn = NULL;
1243                 }
1244
1245         }
1246
1247         return tn;
1248
1249 }
1250
1251 static int yaffs_PruneFileStructure(yaffs_Device * dev,
1252                                     yaffs_FileStructure * fStruct)
1253 {
1254         int i;
1255         int hasData;
1256         int done = 0;
1257         yaffs_Tnode *tn;
1258
1259         if (fStruct->topLevel > 0) {
1260                 fStruct->top =
1261                     yaffs_PruneWorker(dev, fStruct->top, fStruct->topLevel, 0);
1262
1263                 /* Now we have a tree with all the non-zero branches NULL but the height
1264                  * is the same as it was.
1265                  * Let's see if we can trim internal tnodes to shorten the tree.
1266                  * We can do this if only the 0th element in the tnode is in use
1267                  * (ie all the non-zero are NULL)
1268                  */
1269
1270                 while (fStruct->topLevel && !done) {
1271                         tn = fStruct->top;
1272
1273                         hasData = 0;
1274                         for (i = 1; i < YAFFS_NTNODES_INTERNAL; i++) {
1275                                 if (tn->internal[i]) {
1276                                         hasData++;
1277                                 }
1278                         }
1279
1280                         if (!hasData) {
1281                                 fStruct->top = tn->internal[0];
1282                                 fStruct->topLevel--;
1283                                 yaffs_FreeTnode(dev, tn);
1284                         } else {
1285                                 done = 1;
1286                         }
1287                 }
1288         }
1289
1290         return YAFFS_OK;
1291 }
1292
1293 /*-------------------- End of File Structure functions.-------------------*/
1294
1295 /* yaffs_CreateFreeObjects creates a bunch more objects and
1296  * adds them to the object free list.
1297  */
1298 static int yaffs_CreateFreeObjects(yaffs_Device * dev, int nObjects)
1299 {
1300         int i;
1301         yaffs_Object *newObjects;
1302         yaffs_ObjectList *list;
1303
1304         if (nObjects < 1)
1305                 return YAFFS_OK;
1306
1307         /* make these things */
1308         newObjects = YMALLOC(nObjects * sizeof(yaffs_Object));
1309
1310         if (!newObjects) {
1311                 T(YAFFS_TRACE_ALLOCATE,
1312                   (TSTR("yaffs: Could not allocate more objects" TENDSTR)));
1313                 return YAFFS_FAIL;
1314         }
1315
1316         /* Hook them into the free list */
1317         for (i = 0; i < nObjects - 1; i++) {
1318                 newObjects[i].siblings.next =
1319                     (struct list_head *)(&newObjects[i + 1]);
1320         }
1321
1322         newObjects[nObjects - 1].siblings.next = (void *)dev->freeObjects;
1323         dev->freeObjects = newObjects;
1324         dev->nFreeObjects += nObjects;
1325         dev->nObjectsCreated += nObjects;
1326
1327         /* Now add this bunch of Objects to a list for freeing up. */
1328
1329         list = YMALLOC(sizeof(yaffs_ObjectList));
1330         if (!list) {
1331                 T(YAFFS_TRACE_ALLOCATE,
1332                   (TSTR("Could not add objects to management list" TENDSTR)));
1333         } else {
1334                 list->objects = newObjects;
1335                 list->next = dev->allocatedObjectList;
1336                 dev->allocatedObjectList = list;
1337         }
1338
1339         return YAFFS_OK;
1340 }
1341
1342
1343 /* AllocateEmptyObject gets us a clean Object. Tries to make allocate more if we run out */
1344 static yaffs_Object *yaffs_AllocateEmptyObject(yaffs_Device * dev)
1345 {
1346         yaffs_Object *tn = NULL;
1347
1348         /* If there are none left make more */
1349         if (!dev->freeObjects) {
1350                 yaffs_CreateFreeObjects(dev, YAFFS_ALLOCATION_NOBJECTS);
1351         }
1352
1353         if (dev->freeObjects) {
1354                 tn = dev->freeObjects;
1355                 dev->freeObjects =
1356                     (yaffs_Object *) (dev->freeObjects->siblings.next);
1357                 dev->nFreeObjects--;
1358
1359                 /* Now sweeten it up... */
1360
1361                 memset(tn, 0, sizeof(yaffs_Object));
1362                 tn->myDev = dev;
1363                 tn->chunkId = -1;
1364                 tn->variantType = YAFFS_OBJECT_TYPE_UNKNOWN;
1365                 INIT_LIST_HEAD(&(tn->hardLinks));
1366                 INIT_LIST_HEAD(&(tn->hashLink));
1367                 INIT_LIST_HEAD(&tn->siblings);
1368
1369                 /* Add it to the lost and found directory.
1370                  * NB Can't put root or lostNFound in lostNFound so
1371                  * check if lostNFound exists first
1372                  */
1373                 if (dev->lostNFoundDir) {
1374                         yaffs_AddObjectToDirectory(dev->lostNFoundDir, tn);
1375                 }
1376         }
1377
1378         return tn;
1379 }
1380
1381 static yaffs_Object *yaffs_CreateFakeDirectory(yaffs_Device * dev, int number,
1382                                                __u32 mode)
1383 {
1384
1385         yaffs_Object *obj =
1386             yaffs_CreateNewObject(dev, number, YAFFS_OBJECT_TYPE_DIRECTORY);
1387         if (obj) {
1388                 obj->fake = 1;          /* it is fake so it has no NAND presence... */
1389                 obj->renameAllowed = 0; /* ... and we're not allowed to rename it... */
1390                 obj->unlinkAllowed = 0; /* ... or unlink it */
1391                 obj->deleted = 0;
1392                 obj->unlinked = 0;
1393                 obj->yst_mode = mode;
1394                 obj->myDev = dev;
1395                 obj->chunkId = 0;       /* Not a valid chunk. */
1396         }
1397
1398         return obj;
1399
1400 }
1401
1402 static void yaffs_UnhashObject(yaffs_Object * tn)
1403 {
1404         int bucket;
1405         yaffs_Device *dev = tn->myDev;
1406
1407         /* If it is still linked into the bucket list, free from the list */
1408         if (!list_empty(&tn->hashLink)) {
1409                 list_del_init(&tn->hashLink);
1410                 bucket = yaffs_HashFunction(tn->objectId);
1411                 dev->objectBucket[bucket].count--;
1412         }
1413
1414 }
1415
1416 /*  FreeObject frees up a Object and puts it back on the free list */
1417 static void yaffs_FreeObject(yaffs_Object * tn)
1418 {
1419
1420         yaffs_Device *dev = tn->myDev;
1421
1422 #ifdef  __KERNEL__
1423         if (tn->myInode) {
1424                 /* We're still hooked up to a cached inode.
1425                  * Don't delete now, but mark for later deletion
1426                  */
1427                 tn->deferedFree = 1;
1428                 return;
1429         }
1430 #endif
1431
1432         yaffs_UnhashObject(tn);
1433
1434         /* Link into the free list. */
1435         tn->siblings.next = (struct list_head *)(dev->freeObjects);
1436         dev->freeObjects = tn;
1437         dev->nFreeObjects++;
1438 }
1439
1440 #ifdef __KERNEL__
1441
1442 void yaffs_HandleDeferedFree(yaffs_Object * obj)
1443 {
1444         if (obj->deferedFree) {
1445                 yaffs_FreeObject(obj);
1446         }
1447 }
1448
1449 #endif
1450
1451 static void yaffs_DeinitialiseObjects(yaffs_Device * dev)
1452 {
1453         /* Free the list of allocated Objects */
1454
1455         yaffs_ObjectList *tmp;
1456
1457         while (dev->allocatedObjectList) {
1458                 tmp = dev->allocatedObjectList->next;
1459                 YFREE(dev->allocatedObjectList->objects);
1460                 YFREE(dev->allocatedObjectList);
1461
1462                 dev->allocatedObjectList = tmp;
1463         }
1464
1465         dev->freeObjects = NULL;
1466         dev->nFreeObjects = 0;
1467 }
1468
1469 static void yaffs_InitialiseObjects(yaffs_Device * dev)
1470 {
1471         int i;
1472
1473         dev->allocatedObjectList = NULL;
1474         dev->freeObjects = NULL;
1475         dev->nFreeObjects = 0;
1476
1477         for (i = 0; i < YAFFS_NOBJECT_BUCKETS; i++) {
1478                 INIT_LIST_HEAD(&dev->objectBucket[i].list);
1479                 dev->objectBucket[i].count = 0;
1480         }
1481
1482 }
1483
1484 static int yaffs_FindNiceObjectBucket(yaffs_Device * dev)
1485 {
1486         static int x = 0;
1487         int i;
1488         int l = 999;
1489         int lowest = 999999;
1490
1491         /* First let's see if we can find one that's empty. */
1492
1493         for (i = 0; i < 10 && lowest > 0; i++) {
1494                 x++;
1495                 x %= YAFFS_NOBJECT_BUCKETS;
1496                 if (dev->objectBucket[x].count < lowest) {
1497                         lowest = dev->objectBucket[x].count;
1498                         l = x;
1499                 }
1500
1501         }
1502
1503         /* If we didn't find an empty list, then try
1504          * looking a bit further for a short one
1505          */
1506
1507         for (i = 0; i < 10 && lowest > 3; i++) {
1508                 x++;
1509                 x %= YAFFS_NOBJECT_BUCKETS;
1510                 if (dev->objectBucket[x].count < lowest) {
1511                         lowest = dev->objectBucket[x].count;
1512                         l = x;
1513                 }
1514
1515         }
1516
1517         return l;
1518 }
1519
1520 static int yaffs_CreateNewObjectNumber(yaffs_Device * dev)
1521 {
1522         int bucket = yaffs_FindNiceObjectBucket(dev);
1523
1524         /* Now find an object value that has not already been taken
1525          * by scanning the list.
1526          */
1527
1528         int found = 0;
1529         struct list_head *i;
1530
1531         __u32 n = (__u32) bucket;
1532
1533         /* yaffs_CheckObjectHashSanity();  */
1534
1535         while (!found) {
1536                 found = 1;
1537                 n += YAFFS_NOBJECT_BUCKETS;
1538                 if (1 || dev->objectBucket[bucket].count > 0) {
1539                         list_for_each(i, &dev->objectBucket[bucket].list) {
1540                                 /* If there is already one in the list */
1541                                 if (i
1542                                     && list_entry(i, yaffs_Object,
1543                                                   hashLink)->objectId == n) {
1544                                         found = 0;
1545                                 }
1546                         }
1547                 }
1548         }
1549
1550
1551         return n;
1552 }
1553
1554 static void yaffs_HashObject(yaffs_Object * in)
1555 {
1556         int bucket = yaffs_HashFunction(in->objectId);
1557         yaffs_Device *dev = in->myDev;
1558
1559         list_add(&in->hashLink, &dev->objectBucket[bucket].list);
1560         dev->objectBucket[bucket].count++;
1561
1562 }
1563
1564 yaffs_Object *yaffs_FindObjectByNumber(yaffs_Device * dev, __u32 number)
1565 {
1566         int bucket = yaffs_HashFunction(number);
1567         struct list_head *i;
1568         yaffs_Object *in;
1569
1570         list_for_each(i, &dev->objectBucket[bucket].list) {
1571                 /* Look if it is in the list */
1572                 if (i) {
1573                         in = list_entry(i, yaffs_Object, hashLink);
1574                         if (in->objectId == number) {
1575 #ifdef __KERNEL__
1576                                 /* Don't tell the VFS about this one if it is defered free */
1577                                 if (in->deferedFree)
1578                                         return NULL;
1579 #endif
1580
1581                                 return in;
1582                         }
1583                 }
1584         }
1585
1586         return NULL;
1587 }
1588
1589 yaffs_Object *yaffs_CreateNewObject(yaffs_Device * dev, int number,
1590                                     yaffs_ObjectType type)
1591 {
1592
1593         yaffs_Object *theObject;
1594
1595         if (number < 0) {
1596                 number = yaffs_CreateNewObjectNumber(dev);
1597         }
1598
1599         theObject = yaffs_AllocateEmptyObject(dev);
1600
1601         if (theObject) {
1602                 theObject->fake = 0;
1603                 theObject->renameAllowed = 1;
1604                 theObject->unlinkAllowed = 1;
1605                 theObject->objectId = number;
1606                 yaffs_HashObject(theObject);
1607                 theObject->variantType = type;
1608 #ifdef CONFIG_YAFFS_WINCE
1609                 yfsd_WinFileTimeNow(theObject->win_atime);
1610                 theObject->win_ctime[0] = theObject->win_mtime[0] =
1611                     theObject->win_atime[0];
1612                 theObject->win_ctime[1] = theObject->win_mtime[1] =
1613                     theObject->win_atime[1];
1614
1615 #else
1616
1617                 theObject->yst_atime = theObject->yst_mtime =
1618                     theObject->yst_ctime = Y_CURRENT_TIME;
1619 #endif
1620                 switch (type) {
1621                 case YAFFS_OBJECT_TYPE_FILE:
1622                         theObject->variant.fileVariant.fileSize = 0;
1623                         theObject->variant.fileVariant.scannedFileSize = 0;
1624                         theObject->variant.fileVariant.shrinkSize = 0xFFFFFFFF; /* max __u32 */
1625                         theObject->variant.fileVariant.topLevel = 0;
1626                         theObject->variant.fileVariant.top =
1627                             yaffs_GetTnode(dev);
1628                         break;
1629                 case YAFFS_OBJECT_TYPE_DIRECTORY:
1630                         INIT_LIST_HEAD(&theObject->variant.directoryVariant.
1631                                        children);
1632                         break;
1633                 case YAFFS_OBJECT_TYPE_SYMLINK:
1634                 case YAFFS_OBJECT_TYPE_HARDLINK:
1635                 case YAFFS_OBJECT_TYPE_SPECIAL:
1636                         /* No action required */
1637                         break;
1638                 case YAFFS_OBJECT_TYPE_UNKNOWN:
1639                         /* todo this should not happen */
1640                         break;
1641                 }
1642         }
1643
1644         return theObject;
1645 }
1646
1647 static yaffs_Object *yaffs_FindOrCreateObjectByNumber(yaffs_Device * dev,
1648                                                       int number,
1649                                                       yaffs_ObjectType type)
1650 {
1651         yaffs_Object *theObject = NULL;
1652
1653         if (number > 0) {
1654                 theObject = yaffs_FindObjectByNumber(dev, number);
1655         }
1656
1657         if (!theObject) {
1658                 theObject = yaffs_CreateNewObject(dev, number, type);
1659         }
1660
1661         return theObject;
1662
1663 }
1664
1665
1666 static YCHAR *yaffs_CloneString(const YCHAR * str)
1667 {
1668         YCHAR *newStr = NULL;
1669
1670         if (str && *str) {
1671                 newStr = YMALLOC((yaffs_strlen(str) + 1) * sizeof(YCHAR));
1672                 yaffs_strcpy(newStr, str);
1673         }
1674
1675         return newStr;
1676
1677 }
1678
1679 /*
1680  * Mknod (create) a new object.
1681  * equivalentObject only has meaning for a hard link;
1682  * aliasString only has meaning for a sumlink.
1683  * rdev only has meaning for devices (a subset of special objects)
1684  */
1685
1686 static yaffs_Object *yaffs_MknodObject(yaffs_ObjectType type,
1687                                        yaffs_Object * parent,
1688                                        const YCHAR * name,
1689                                        __u32 mode,
1690                                        __u32 uid,
1691                                        __u32 gid,
1692                                        yaffs_Object * equivalentObject,
1693                                        const YCHAR * aliasString, __u32 rdev)
1694 {
1695         yaffs_Object *in;
1696
1697         yaffs_Device *dev = parent->myDev;
1698
1699         /* Check if the entry exists. If it does then fail the call since we don't want a dup.*/
1700         if (yaffs_FindObjectByName(parent, name)) {
1701                 return NULL;
1702         }
1703
1704         in = yaffs_CreateNewObject(dev, -1, type);
1705
1706         if (in) {
1707                 in->chunkId = -1;
1708                 in->valid = 1;
1709                 in->variantType = type;
1710
1711                 in->yst_mode = mode;
1712
1713 #ifdef CONFIG_YAFFS_WINCE
1714                 yfsd_WinFileTimeNow(in->win_atime);
1715                 in->win_ctime[0] = in->win_mtime[0] = in->win_atime[0];
1716                 in->win_ctime[1] = in->win_mtime[1] = in->win_atime[1];
1717
1718 #else
1719                 in->yst_atime = in->yst_mtime = in->yst_ctime = Y_CURRENT_TIME;
1720
1721                 in->yst_rdev = rdev;
1722                 in->yst_uid = uid;
1723                 in->yst_gid = gid;
1724 #endif
1725                 in->nDataChunks = 0;
1726
1727                 yaffs_SetObjectName(in, name);
1728                 in->dirty = 1;
1729
1730                 yaffs_AddObjectToDirectory(parent, in);
1731
1732                 in->myDev = parent->myDev;
1733
1734                 switch (type) {
1735                 case YAFFS_OBJECT_TYPE_SYMLINK:
1736                         in->variant.symLinkVariant.alias =
1737                             yaffs_CloneString(aliasString);
1738                         break;
1739                 case YAFFS_OBJECT_TYPE_HARDLINK:
1740                         in->variant.hardLinkVariant.equivalentObject =
1741                             equivalentObject;
1742                         in->variant.hardLinkVariant.equivalentObjectId =
1743                             equivalentObject->objectId;
1744                         list_add(&in->hardLinks, &equivalentObject->hardLinks);
1745                         break;
1746                 case YAFFS_OBJECT_TYPE_FILE:
1747                 case YAFFS_OBJECT_TYPE_DIRECTORY:
1748                 case YAFFS_OBJECT_TYPE_SPECIAL:
1749                 case YAFFS_OBJECT_TYPE_UNKNOWN:
1750                         /* do nothing */
1751                         break;
1752                 }
1753
1754                 if (yaffs_UpdateObjectHeader(in, name, 0, 0, 0) < 0) {
1755                         /* Could not create the object header, fail the creation */
1756                         yaffs_DestroyObject(in);
1757                         in = NULL;
1758                 }
1759
1760         }
1761
1762         return in;
1763 }
1764
1765 yaffs_Object *yaffs_MknodFile(yaffs_Object * parent, const YCHAR * name,
1766                               __u32 mode, __u32 uid, __u32 gid)
1767 {
1768         return yaffs_MknodObject(YAFFS_OBJECT_TYPE_FILE, parent, name, mode,
1769                                  uid, gid, NULL, NULL, 0);
1770 }
1771
1772 yaffs_Object *yaffs_MknodDirectory(yaffs_Object * parent, const YCHAR * name,
1773                                    __u32 mode, __u32 uid, __u32 gid)
1774 {
1775         return yaffs_MknodObject(YAFFS_OBJECT_TYPE_DIRECTORY, parent, name,
1776                                  mode, uid, gid, NULL, NULL, 0);
1777 }
1778
1779 yaffs_Object *yaffs_MknodSpecial(yaffs_Object * parent, const YCHAR * name,
1780                                  __u32 mode, __u32 uid, __u32 gid, __u32 rdev)
1781 {
1782         return yaffs_MknodObject(YAFFS_OBJECT_TYPE_SPECIAL, parent, name, mode,
1783                                  uid, gid, NULL, NULL, rdev);
1784 }
1785
1786 yaffs_Object *yaffs_MknodSymLink(yaffs_Object * parent, const YCHAR * name,
1787                                  __u32 mode, __u32 uid, __u32 gid,
1788                                  const YCHAR * alias)
1789 {
1790         return yaffs_MknodObject(YAFFS_OBJECT_TYPE_SYMLINK, parent, name, mode,
1791                                  uid, gid, NULL, alias, 0);
1792 }
1793
1794 /* yaffs_Link returns the object id of the equivalent object.*/
1795 yaffs_Object *yaffs_Link(yaffs_Object * parent, const YCHAR * name,
1796                          yaffs_Object * equivalentObject)
1797 {
1798         /* Get the real object in case we were fed a hard link as an equivalent object */
1799         equivalentObject = yaffs_GetEquivalentObject(equivalentObject);
1800
1801         if (yaffs_MknodObject
1802             (YAFFS_OBJECT_TYPE_HARDLINK, parent, name, 0, 0, 0,
1803              equivalentObject, NULL, 0)) {
1804                 return equivalentObject;
1805         } else {
1806                 return NULL;
1807         }
1808
1809 }
1810
1811 static int yaffs_ChangeObjectName(yaffs_Object * obj, yaffs_Object * newDir,
1812                                   const YCHAR * newName, int force, int shadows)
1813 {
1814         int unlinkOp;
1815         int deleteOp;
1816
1817         yaffs_Object *existingTarget;
1818
1819         if (newDir == NULL) {
1820                 newDir = obj->parent;   /* use the old directory */
1821         }
1822
1823         if (newDir->variantType != YAFFS_OBJECT_TYPE_DIRECTORY) {
1824                 T(YAFFS_TRACE_ALWAYS,
1825                   (TSTR
1826                    ("tragendy: yaffs_ChangeObjectName: newDir is not a directory"
1827                     TENDSTR)));
1828                 YBUG();
1829         }
1830
1831         /* TODO: Do we need this different handling for YAFFS2 and YAFFS1?? */
1832         if (obj->myDev->isYaffs2) {
1833                 unlinkOp = (newDir == obj->myDev->unlinkedDir);
1834         } else {
1835                 unlinkOp = (newDir == obj->myDev->unlinkedDir
1836                             && obj->variantType == YAFFS_OBJECT_TYPE_FILE);
1837         }
1838
1839         deleteOp = (newDir == obj->myDev->deletedDir);
1840
1841         existingTarget = yaffs_FindObjectByName(newDir, newName);
1842
1843         /* If the object is a file going into the unlinked directory,
1844          *   then it is OK to just stuff it in since duplicate names are allowed.
1845          *   else only proceed if the new name does not exist and if we're putting
1846          *   it into a directory.
1847          */
1848         if ((unlinkOp ||
1849              deleteOp ||
1850              force ||
1851              (shadows > 0) ||
1852              !existingTarget) &&
1853             newDir->variantType == YAFFS_OBJECT_TYPE_DIRECTORY) {
1854                 yaffs_SetObjectName(obj, newName);
1855                 obj->dirty = 1;
1856
1857                 yaffs_AddObjectToDirectory(newDir, obj);
1858
1859                 if (unlinkOp)
1860                         obj->unlinked = 1;
1861
1862                 /* If it is a deletion then we mark it as a shrink for gc purposes. */
1863                 if (yaffs_UpdateObjectHeader(obj, newName, 0, deleteOp, shadows)>= 0)
1864                         return YAFFS_OK;
1865         }
1866
1867         return YAFFS_FAIL;
1868 }
1869
1870 int yaffs_RenameObject(yaffs_Object * oldDir, const YCHAR * oldName,
1871                        yaffs_Object * newDir, const YCHAR * newName)
1872 {
1873         yaffs_Object *obj;
1874         yaffs_Object *existingTarget;
1875         int force = 0;
1876
1877 #ifdef CONFIG_YAFFS_CASE_INSENSITIVE
1878         /* Special case for case insemsitive systems (eg. WinCE).
1879          * While look-up is case insensitive, the name isn't.
1880          * Therefore we might want to change x.txt to X.txt
1881         */
1882         if (oldDir == newDir && yaffs_strcmp(oldName, newName) == 0) {
1883                 force = 1;
1884         }
1885 #endif
1886
1887         obj = yaffs_FindObjectByName(oldDir, oldName);
1888         /* Check new name to long. */
1889         if (obj->variantType == YAFFS_OBJECT_TYPE_SYMLINK &&
1890             yaffs_strlen(newName) > YAFFS_MAX_ALIAS_LENGTH)
1891           /* ENAMETOOLONG */
1892           return YAFFS_FAIL;
1893         else if (obj->variantType != YAFFS_OBJECT_TYPE_SYMLINK &&
1894                  yaffs_strlen(newName) > YAFFS_MAX_NAME_LENGTH)
1895           /* ENAMETOOLONG */
1896           return YAFFS_FAIL;
1897
1898         if (obj && obj->renameAllowed) {
1899
1900                 /* Now do the handling for an existing target, if there is one */
1901
1902                 existingTarget = yaffs_FindObjectByName(newDir, newName);
1903                 if (existingTarget &&
1904                     existingTarget->variantType == YAFFS_OBJECT_TYPE_DIRECTORY &&
1905                     !list_empty(&existingTarget->variant.directoryVariant.children)) {
1906                         /* There is a target that is a non-empty directory, so we fail */
1907                         return YAFFS_FAIL;      /* EEXIST or ENOTEMPTY */
1908                 } else if (existingTarget && existingTarget != obj) {
1909                         /* Nuke the target first, using shadowing,
1910                          * but only if it isn't the same object
1911                          */
1912                         yaffs_ChangeObjectName(obj, newDir, newName, force,
1913                                                existingTarget->objectId);
1914                         yaffs_UnlinkObject(existingTarget);
1915                 }
1916
1917                 return yaffs_ChangeObjectName(obj, newDir, newName, 1, 0);
1918         }
1919         return YAFFS_FAIL;
1920 }
1921
1922 /*------------------------- Block Management and Page Allocation ----------------*/
1923
1924 static int yaffs_InitialiseBlocks(yaffs_Device * dev)
1925 {
1926         int nBlocks = dev->internalEndBlock - dev->internalStartBlock + 1;
1927
1928         dev->allocationBlock = -1;      /* force it to get a new one */
1929
1930         /* Todo we're assuming the malloc will pass. */
1931         dev->blockInfo = YMALLOC(nBlocks * sizeof(yaffs_BlockInfo));
1932         if(!dev->blockInfo){
1933                 dev->blockInfo = YMALLOC_ALT(nBlocks * sizeof(yaffs_BlockInfo));
1934                 dev->blockInfoAlt = 1;
1935         }
1936         else
1937                 dev->blockInfoAlt = 0;
1938
1939         /* Set up dynamic blockinfo stuff. */
1940         dev->chunkBitmapStride = (dev->nChunksPerBlock + 7) / 8; // round up bytes
1941         dev->chunkBits = YMALLOC(dev->chunkBitmapStride * nBlocks);
1942         if(!dev->chunkBits){
1943                 dev->chunkBits = YMALLOC_ALT(dev->chunkBitmapStride * nBlocks);
1944                 dev->chunkBitsAlt = 1;
1945         }
1946         else
1947                 dev->chunkBitsAlt = 0;
1948
1949         if (dev->blockInfo && dev->chunkBits) {
1950                 memset(dev->blockInfo, 0, nBlocks * sizeof(yaffs_BlockInfo));
1951                 memset(dev->chunkBits, 0, dev->chunkBitmapStride * nBlocks);
1952                 return YAFFS_OK;
1953         }
1954
1955         return YAFFS_FAIL;
1956
1957 }
1958
1959 static void yaffs_DeinitialiseBlocks(yaffs_Device * dev)
1960 {
1961         if(dev->blockInfoAlt)
1962                 YFREE_ALT(dev->blockInfo);
1963         else
1964                 YFREE(dev->blockInfo);
1965         dev->blockInfoAlt = 0;
1966
1967         dev->blockInfo = NULL;
1968
1969         if(dev->chunkBitsAlt)
1970                 YFREE_ALT(dev->chunkBits);
1971         else
1972                 YFREE(dev->chunkBits);
1973         dev->chunkBitsAlt = 0;
1974         dev->chunkBits = NULL;
1975 }
1976
1977 static int yaffs_BlockNotDisqualifiedFromGC(yaffs_Device * dev,
1978                                             yaffs_BlockInfo * bi)
1979 {
1980         int i;
1981         __u32 seq;
1982         yaffs_BlockInfo *b;
1983
1984         if (!dev->isYaffs2)
1985                 return 1;       /* disqualification only applies to yaffs2. */
1986
1987         if (!bi->hasShrinkHeader)
1988                 return 1;       /* can gc */
1989
1990         /* Find the oldest dirty sequence number if we don't know it and save it
1991          * so we don't have to keep recomputing it.
1992          */
1993         if (!dev->oldestDirtySequence) {
1994                 seq = dev->sequenceNumber;
1995
1996                 for (i = dev->internalStartBlock; i <= dev->internalEndBlock;
1997                      i++) {
1998                         b = yaffs_GetBlockInfo(dev, i);
1999                         if (b->blockState == YAFFS_BLOCK_STATE_FULL &&
2000                             (b->pagesInUse - b->softDeletions) <
2001                             dev->nChunksPerBlock && b->sequenceNumber < seq) {
2002                                 seq = b->sequenceNumber;
2003                         }
2004                 }
2005                 dev->oldestDirtySequence = seq;
2006         }
2007
2008         /* Can't do gc of this block if there are any blocks older than this one that have
2009          * discarded pages.
2010          */
2011         return (bi->sequenceNumber <= dev->oldestDirtySequence);
2012
2013         return 1;
2014
2015 }
2016
2017 /* FindDiretiestBlock is used to select the dirtiest block (or close enough)
2018  * for garbage collection.
2019  */
2020
2021 static int yaffs_FindBlockForGarbageCollection(yaffs_Device * dev,
2022                                                int aggressive)
2023 {
2024
2025         int b = dev->currentDirtyChecker;
2026
2027         int i;
2028         int iterations;
2029         int dirtiest = -1;
2030         int pagesInUse;
2031         int prioritised=0;
2032         yaffs_BlockInfo *bi;
2033         static int nonAggressiveSkip = 0;
2034         int pendingPrioritisedExist = 0;
2035
2036         /* First let's see if we need to grab a prioritised block */
2037         if(dev->hasPendingPrioritisedGCs){
2038                 for(i = dev->internalStartBlock; i < dev->internalEndBlock && !prioritised; i++){
2039
2040                         bi = yaffs_GetBlockInfo(dev, i);
2041                         if(bi->gcPrioritise)
2042                                 pendingPrioritisedExist = 1;
2043                         if(bi->blockState == YAFFS_BLOCK_STATE_FULL &&
2044                            bi->gcPrioritise &&
2045                            yaffs_BlockNotDisqualifiedFromGC(dev, bi)){
2046                                 pagesInUse = (bi->pagesInUse - bi->softDeletions);
2047                                 dirtiest = i;
2048                                 prioritised = 1;
2049                                 aggressive = 1; /* Fool the non-aggressive skip logiv below */
2050                         }
2051                 }
2052
2053                 if(!pendingPrioritisedExist) /* None found, so we can clear this */
2054                         dev->hasPendingPrioritisedGCs = 0;
2055         }
2056
2057         /* If we're doing aggressive GC then we are happy to take a less-dirty block, and
2058          * search harder.
2059          * else (we're doing a leasurely gc), then we only bother to do this if the
2060          * block has only a few pages in use.
2061          */
2062
2063         nonAggressiveSkip--;
2064
2065         if (!aggressive && (nonAggressiveSkip > 0)) {
2066                 return -1;
2067         }
2068
2069         if(!prioritised)
2070                 pagesInUse =
2071                         (aggressive) ? dev->nChunksPerBlock : YAFFS_PASSIVE_GC_CHUNKS + 1;
2072
2073         if (aggressive) {
2074                 iterations =
2075                     dev->internalEndBlock - dev->internalStartBlock + 1;
2076         } else {
2077                 iterations =
2078                     dev->internalEndBlock - dev->internalStartBlock + 1;
2079                 iterations = iterations / 16;
2080                 if (iterations > 200) {
2081                         iterations = 200;
2082                 }
2083         }
2084
2085         for (i = 0; i <= iterations && pagesInUse > 0 && !prioritised; i++) {
2086                 b++;
2087                 if (b < dev->internalStartBlock || b > dev->internalEndBlock) {
2088                         b = dev->internalStartBlock;
2089                 }
2090
2091                 if (b < dev->internalStartBlock || b > dev->internalEndBlock) {
2092                         T(YAFFS_TRACE_ERROR,
2093                           (TSTR("**>> Block %d is not valid" TENDSTR), b));
2094                         YBUG();
2095                 }
2096
2097                 bi = yaffs_GetBlockInfo(dev, b);
2098
2099 #if 0
2100                 if (bi->blockState == YAFFS_BLOCK_STATE_CHECKPOINT) {
2101                         dirtiest = b;
2102                         pagesInUse = 0;
2103                 }
2104                 else
2105 #endif
2106
2107                 if (bi->blockState == YAFFS_BLOCK_STATE_FULL &&
2108                        (bi->pagesInUse - bi->softDeletions) < pagesInUse &&
2109                         yaffs_BlockNotDisqualifiedFromGC(dev, bi)) {
2110                         dirtiest = b;
2111                         pagesInUse = (bi->pagesInUse - bi->softDeletions);
2112                 }
2113         }
2114
2115         dev->currentDirtyChecker = b;
2116
2117         if (dirtiest > 0) {
2118                 T(YAFFS_TRACE_GC,
2119                   (TSTR("GC Selected block %d with %d free, prioritised:%d" TENDSTR), dirtiest,
2120                    dev->nChunksPerBlock - pagesInUse,prioritised));
2121         }
2122
2123         dev->oldestDirtySequence = 0;
2124
2125         if (dirtiest > 0) {
2126                 nonAggressiveSkip = 4;
2127         }
2128
2129         return dirtiest;
2130 }
2131
2132 static void yaffs_BlockBecameDirty(yaffs_Device * dev, int blockNo)
2133 {
2134         yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, blockNo);
2135
2136         int erasedOk = 0;
2137
2138         /* If the block is still healthy erase it and mark as clean.
2139          * If the block has had a data failure, then retire it.
2140          */
2141         bi->blockState = YAFFS_BLOCK_STATE_DIRTY;
2142
2143         if (!bi->needsRetiring) {
2144                 yaffs_InvalidateCheckpoint(dev);
2145                 erasedOk = yaffs_EraseBlockInNAND(dev, blockNo);
2146                 if (!erasedOk) {
2147                         dev->nErasureFailures++;
2148                         T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
2149                           (TSTR("**>> Erasure failed %d" TENDSTR), blockNo));
2150                 }
2151         }
2152
2153         if (erasedOk && (yaffs_traceMask & YAFFS_TRACE_ERASE)) {
2154                 int i;
2155                 for (i = 0; i < dev->nChunksPerBlock; i++) {
2156                         if (!yaffs_CheckChunkErased
2157                             (dev, blockNo * dev->nChunksPerBlock + i)) {
2158                                 T(YAFFS_TRACE_ERROR,
2159                                   (TSTR
2160                                    (">>Block %d erasure supposedly OK, but chunk %d not erased"
2161                                     TENDSTR), blockNo, i));
2162                         }
2163                 }
2164         }
2165
2166         if (erasedOk) {
2167                 /* Clean it up... */
2168                 bi->blockState = YAFFS_BLOCK_STATE_EMPTY;
2169                 dev->nErasedBlocks++;
2170                 bi->pagesInUse = 0;
2171                 bi->softDeletions = 0;
2172                 bi->hasShrinkHeader = 0;
2173                 bi->skipErasedCheck = 1;  /* This is clean, so no need to check */
2174                 bi->gcPrioritise = 0;
2175                 yaffs_ClearChunkBits(dev, blockNo);
2176
2177                 T(YAFFS_TRACE_ERASE,
2178                   (TSTR("Erased block %d" TENDSTR), blockNo));
2179         } else {
2180                 dev->nFreeChunks -= dev->nChunksPerBlock;       /* We lost a block of free space */
2181
2182                 yaffs_RetireBlock(dev, blockNo);
2183                 T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
2184                   (TSTR("**>> Block %d retired" TENDSTR), blockNo));
2185         }
2186 }
2187
2188 static int yaffs_FindBlockForAllocation(yaffs_Device * dev)
2189 {
2190         int i;
2191
2192         yaffs_BlockInfo *bi;
2193
2194         if (dev->nErasedBlocks < 1) {
2195                 /* Hoosterman we've got a problem.
2196                  * Can't get space to gc
2197                  */
2198                 T(YAFFS_TRACE_ERROR,
2199                   (TSTR("yaffs tragedy: no more eraased blocks" TENDSTR)));
2200
2201                 return -1;
2202         }
2203
2204         /* Find an empty block. */
2205
2206         for (i = dev->internalStartBlock; i <= dev->internalEndBlock; i++) {
2207                 dev->allocationBlockFinder++;
2208                 if (dev->allocationBlockFinder < dev->internalStartBlock
2209                     || dev->allocationBlockFinder > dev->internalEndBlock) {
2210                         dev->allocationBlockFinder = dev->internalStartBlock;
2211                 }
2212
2213                 bi = yaffs_GetBlockInfo(dev, dev->allocationBlockFinder);
2214
2215                 if (bi->blockState == YAFFS_BLOCK_STATE_EMPTY) {
2216                         bi->blockState = YAFFS_BLOCK_STATE_ALLOCATING;
2217                         dev->sequenceNumber++;
2218                         bi->sequenceNumber = dev->sequenceNumber;
2219                         dev->nErasedBlocks--;
2220                         T(YAFFS_TRACE_ALLOCATE,
2221                           (TSTR("Allocated block %d, seq  %d, %d left" TENDSTR),
2222                            dev->allocationBlockFinder, dev->sequenceNumber,
2223                            dev->nErasedBlocks));
2224                         return dev->allocationBlockFinder;
2225                 }
2226         }
2227
2228         T(YAFFS_TRACE_ALWAYS,
2229           (TSTR
2230            ("yaffs tragedy: no more eraased blocks, but there should have been %d"
2231             TENDSTR), dev->nErasedBlocks));
2232
2233         return -1;
2234 }
2235
2236
2237 // Check if there's space to allocate...
2238 // Thinks.... do we need top make this ths same as yaffs_GetFreeChunks()?
2239 static int yaffs_CheckSpaceForAllocation(yaffs_Device * dev)
2240 {
2241         int reservedChunks;
2242         int reservedBlocks = dev->nReservedBlocks;
2243         int checkpointBlocks;
2244
2245         checkpointBlocks =  dev->nCheckpointReservedBlocks - dev->blocksInCheckpoint;
2246         if(checkpointBlocks < 0)
2247                 checkpointBlocks = 0;
2248
2249         reservedChunks = ((reservedBlocks + checkpointBlocks) * dev->nChunksPerBlock);
2250
2251         return (dev->nFreeChunks > reservedChunks);
2252 }
2253
2254 static int yaffs_AllocateChunk(yaffs_Device * dev, int useReserve, yaffs_BlockInfo **blockUsedPtr)
2255 {
2256         int retVal;
2257         yaffs_BlockInfo *bi;
2258
2259         if (dev->allocationBlock < 0) {
2260                 /* Get next block to allocate off */
2261                 dev->allocationBlock = yaffs_FindBlockForAllocation(dev);
2262                 dev->allocationPage = 0;
2263         }
2264
2265         if (!useReserve && !yaffs_CheckSpaceForAllocation(dev)) {
2266                 /* Not enough space to allocate unless we're allowed to use the reserve. */
2267                 return -1;
2268         }
2269
2270         if (dev->nErasedBlocks < dev->nReservedBlocks
2271             && dev->allocationPage == 0) {
2272                 T(YAFFS_TRACE_ALLOCATE, (TSTR("Allocating reserve" TENDSTR)));
2273         }
2274
2275         /* Next page please.... */
2276         if (dev->allocationBlock >= 0) {
2277                 bi = yaffs_GetBlockInfo(dev, dev->allocationBlock);
2278
2279                 retVal = (dev->allocationBlock * dev->nChunksPerBlock) +
2280                     dev->allocationPage;
2281                 bi->pagesInUse++;
2282                 yaffs_SetChunkBit(dev, dev->allocationBlock,
2283                                   dev->allocationPage);
2284
2285                 dev->allocationPage++;
2286
2287                 dev->nFreeChunks--;
2288
2289                 /* If the block is full set the state to full */
2290                 if (dev->allocationPage >= dev->nChunksPerBlock) {
2291                         bi->blockState = YAFFS_BLOCK_STATE_FULL;
2292                         dev->allocationBlock = -1;
2293                 }
2294
2295                 if(blockUsedPtr)
2296                         *blockUsedPtr = bi;
2297
2298                 return retVal;
2299         }
2300
2301         T(YAFFS_TRACE_ERROR,
2302           (TSTR("!!!!!!!!! Allocator out !!!!!!!!!!!!!!!!!" TENDSTR)));
2303
2304         return -1;
2305 }
2306
2307 static int yaffs_GetErasedChunks(yaffs_Device * dev)
2308 {
2309         int n;
2310
2311         n = dev->nErasedBlocks * dev->nChunksPerBlock;
2312
2313         if (dev->allocationBlock > 0) {
2314                 n += (dev->nChunksPerBlock - dev->allocationPage);
2315         }
2316
2317         return n;
2318
2319 }
2320
2321 static int yaffs_GarbageCollectBlock(yaffs_Device * dev, int block)
2322 {
2323         int oldChunk;
2324         int newChunk;
2325         int chunkInBlock;
2326         int markNAND;
2327         int retVal = YAFFS_OK;
2328         int cleanups = 0;
2329         int i;
2330         int isCheckpointBlock;
2331
2332         int chunksBefore = yaffs_GetErasedChunks(dev);
2333         int chunksAfter;
2334
2335         yaffs_ExtendedTags tags;
2336
2337         yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, block);
2338
2339         yaffs_Object *object;
2340
2341         isCheckpointBlock = (bi->blockState == YAFFS_BLOCK_STATE_CHECKPOINT);
2342
2343         bi->blockState = YAFFS_BLOCK_STATE_COLLECTING;
2344
2345         T(YAFFS_TRACE_TRACING,
2346           (TSTR("Collecting block %d, in use %d, shrink %d, " TENDSTR), block,
2347            bi->pagesInUse, bi->hasShrinkHeader));
2348
2349         /*yaffs_VerifyFreeChunks(dev); */
2350
2351         bi->hasShrinkHeader = 0;        /* clear the flag so that the block can erase */
2352
2353         /* Take off the number of soft deleted entries because
2354          * they're going to get really deleted during GC.
2355          */
2356         dev->nFreeChunks -= bi->softDeletions;
2357
2358         dev->isDoingGC = 1;
2359
2360         if (isCheckpointBlock ||
2361             !yaffs_StillSomeChunkBits(dev, block)) {
2362                 T(YAFFS_TRACE_TRACING,
2363                   (TSTR
2364                    ("Collecting block %d that has no chunks in use" TENDSTR),
2365                    block));
2366                 yaffs_BlockBecameDirty(dev, block);
2367         } else {
2368
2369                 __u8 *buffer = yaffs_GetTempBuffer(dev, __LINE__);
2370
2371                 for (chunkInBlock = 0, oldChunk = block * dev->nChunksPerBlock;
2372                      chunkInBlock < dev->nChunksPerBlock
2373                      && yaffs_StillSomeChunkBits(dev, block);
2374                      chunkInBlock++, oldChunk++) {
2375                         if (yaffs_CheckChunkBit(dev, block, chunkInBlock)) {
2376
2377                                 /* This page is in use and might need to be copied off */
2378
2379                                 markNAND = 1;
2380
2381                                 yaffs_InitialiseTags(&tags);
2382
2383                                 yaffs_ReadChunkWithTagsFromNAND(dev, oldChunk,
2384                                                                 buffer, &tags);
2385
2386                                 object =
2387                                     yaffs_FindObjectByNumber(dev,
2388                                                              tags.objectId);
2389
2390                                 T(YAFFS_TRACE_GC_DETAIL,
2391                                   (TSTR
2392                                    ("Collecting page %d, %d %d %d " TENDSTR),
2393                                    chunkInBlock, tags.objectId, tags.chunkId,
2394                                    tags.byteCount));
2395
2396                                 if (!object) {
2397                                         T(YAFFS_TRACE_ERROR,
2398                                           (TSTR
2399                                            ("page %d in gc has no object "
2400                                             TENDSTR), oldChunk));
2401                                 }
2402
2403                                 if (object && object->deleted
2404                                     && tags.chunkId != 0) {
2405                                         /* Data chunk in a deleted file, throw it away
2406                                          * It's a soft deleted data chunk,
2407                                          * No need to copy this, just forget about it and
2408                                          * fix up the object.
2409                                          */
2410
2411                                         object->nDataChunks--;
2412
2413                                         if (object->nDataChunks <= 0) {
2414                                                 /* remeber to clean up the object */
2415                                                 dev->gcCleanupList[cleanups] =
2416                                                     tags.objectId;
2417                                                 cleanups++;
2418                                         }
2419                                         markNAND = 0;
2420                                 } else if (0
2421                                            /* Todo object && object->deleted && object->nDataChunks == 0 */
2422                                            ) {
2423                                         /* Deleted object header with no data chunks.
2424                                          * Can be discarded and the file deleted.
2425                                          */
2426                                         object->chunkId = 0;
2427                                         yaffs_FreeTnode(object->myDev,
2428                                                         object->variant.
2429                                                         fileVariant.top);
2430                                         object->variant.fileVariant.top = NULL;
2431                                         yaffs_DoGenericObjectDeletion(object);
2432
2433                                 } else if (object) {
2434                                         /* It's either a data chunk in a live file or
2435                                          * an ObjectHeader, so we're interested in it.
2436                                          * NB Need to keep the ObjectHeaders of deleted files
2437                                          * until the whole file has been deleted off
2438                                          */
2439                                         tags.serialNumber++;
2440
2441                                         dev->nGCCopies++;
2442
2443                                         if (tags.chunkId == 0) {
2444                                                 /* It is an object Id,
2445                                                  * We need to nuke the shrinkheader flags first
2446                                                  * We no longer want the shrinkHeader flag since its work is done
2447                                                  * and if it is left in place it will mess up scanning.
2448                                                  * Also, clear out any shadowing stuff
2449                                                  */
2450
2451                                                 yaffs_ObjectHeader *oh;
2452                                                 oh = (yaffs_ObjectHeader *)buffer;
2453                                                 oh->isShrink = 0;
2454                                                 oh->shadowsObject = -1;
2455                                                 tags.extraShadows = 0;
2456                                                 tags.extraIsShrinkHeader = 0;
2457                                         }
2458
2459                                         newChunk =
2460                                             yaffs_WriteNewChunkWithTagsToNAND(dev, buffer, &tags, 1);
2461
2462                                         if (newChunk < 0) {
2463                                                 retVal = YAFFS_FAIL;
2464                                         } else {
2465
2466                                                 /* Ok, now fix up the Tnodes etc. */
2467
2468                                                 if (tags.chunkId == 0) {
2469                                                         /* It's a header */
2470                                                         object->chunkId =  newChunk;
2471                                                         object->serial =   tags.serialNumber;
2472                                                 } else {
2473                                                         /* It's a data chunk */
2474                                                         yaffs_PutChunkIntoFile
2475                                                             (object,
2476                                                              tags.chunkId,
2477                                                              newChunk, 0);
2478                                                 }
2479                                         }
2480                                 }
2481
2482                                 yaffs_DeleteChunk(dev, oldChunk, markNAND, __LINE__);
2483
2484                         }
2485                 }
2486
2487                 yaffs_ReleaseTempBuffer(dev, buffer, __LINE__);
2488
2489
2490                 /* Do any required cleanups */
2491                 for (i = 0; i < cleanups; i++) {
2492                         /* Time to delete the file too */
2493                         object =
2494                             yaffs_FindObjectByNumber(dev,
2495                                                      dev->gcCleanupList[i]);
2496                         if (object) {
2497                                 yaffs_FreeTnode(dev,
2498                                                 object->variant.fileVariant.
2499                                                 top);
2500                                 object->variant.fileVariant.top = NULL;
2501                                 T(YAFFS_TRACE_GC,
2502                                   (TSTR
2503                                    ("yaffs: About to finally delete object %d"
2504                                     TENDSTR), object->objectId));
2505                                 yaffs_DoGenericObjectDeletion(object);
2506                                 object->myDev->nDeletedFiles--;
2507                         }
2508
2509                 }
2510
2511         }
2512
2513         if (chunksBefore >= (chunksAfter = yaffs_GetErasedChunks(dev))) {
2514                 T(YAFFS_TRACE_GC,
2515                   (TSTR
2516                    ("gc did not increase free chunks before %d after %d"
2517                     TENDSTR), chunksBefore, chunksAfter));
2518         }
2519
2520         dev->isDoingGC = 0;
2521
2522         return YAFFS_OK;
2523 }
2524
2525 /* New garbage collector
2526  * If we're very low on erased blocks then we do aggressive garbage collection
2527  * otherwise we do "leasurely" garbage collection.
2528  * Aggressive gc looks further (whole array) and will accept less dirty blocks.
2529  * Passive gc only inspects smaller areas and will only accept more dirty blocks.
2530  *
2531  * The idea is to help clear out space in a more spread-out manner.
2532  * Dunno if it really does anything useful.
2533  */
2534 static int yaffs_CheckGarbageCollection(yaffs_Device * dev)
2535 {
2536         int block;
2537         int aggressive;
2538         int gcOk = YAFFS_OK;
2539         int maxTries = 0;
2540
2541         int checkpointBlockAdjust;
2542
2543         if (dev->isDoingGC) {
2544                 /* Bail out so we don't get recursive gc */
2545                 return YAFFS_OK;
2546         }
2547
2548         /* This loop should pass the first time.
2549          * We'll only see looping here if the erase of the collected block fails.
2550          */
2551
2552         do {
2553                 maxTries++;
2554
2555                 checkpointBlockAdjust = (dev->nCheckpointReservedBlocks - dev->blocksInCheckpoint);
2556                 if(checkpointBlockAdjust < 0)
2557                         checkpointBlockAdjust = 0;
2558
2559                 if (dev->nErasedBlocks < (dev->nReservedBlocks + checkpointBlockAdjust)) {
2560                         /* We need a block soon...*/
2561                         aggressive = 1;
2562                 } else {
2563                         /* We're in no hurry */
2564                         aggressive = 0;
2565                 }
2566
2567                 block = yaffs_FindBlockForGarbageCollection(dev, aggressive);
2568
2569                 if (block > 0) {
2570                         dev->garbageCollections++;
2571                         if (!aggressive) {
2572                                 dev->passiveGarbageCollections++;
2573                         }
2574
2575                         T(YAFFS_TRACE_GC,
2576                           (TSTR
2577                            ("yaffs: GC erasedBlocks %d aggressive %d" TENDSTR),
2578                            dev->nErasedBlocks, aggressive));
2579
2580                         gcOk = yaffs_GarbageCollectBlock(dev, block);
2581                 }
2582
2583                 if (dev->nErasedBlocks < (dev->nReservedBlocks) && block > 0) {
2584                         T(YAFFS_TRACE_GC,
2585                           (TSTR
2586                            ("yaffs: GC !!!no reclaim!!! erasedBlocks %d after try %d block %d"
2587                             TENDSTR), dev->nErasedBlocks, maxTries, block));
2588                 }
2589         } while ((dev->nErasedBlocks < dev->nReservedBlocks) && (block > 0)
2590                  && (maxTries < 2));
2591
2592         return aggressive ? gcOk : YAFFS_OK;
2593 }
2594
2595 /*-------------------------  TAGS --------------------------------*/
2596
2597 static int yaffs_TagsMatch(const yaffs_ExtendedTags * tags, int objectId,
2598                            int chunkInObject)
2599 {
2600         return (tags->chunkId == chunkInObject &&
2601                 tags->objectId == objectId && !tags->chunkDeleted) ? 1 : 0;
2602
2603 }
2604
2605
2606 /*-------------------- Data file manipulation -----------------*/
2607
2608 static int yaffs_FindChunkInFile(yaffs_Object * in, int chunkInInode,
2609                                  yaffs_ExtendedTags * tags)
2610 {
2611         /*Get the Tnode, then get the level 0 offset chunk offset */
2612         yaffs_Tnode *tn;
2613         int theChunk = -1;
2614         yaffs_ExtendedTags localTags;
2615         int retVal = -1;
2616
2617         yaffs_Device *dev = in->myDev;
2618
2619         if (!tags) {
2620                 /* Passed a NULL, so use our own tags space */
2621                 tags = &localTags;
2622         }
2623
2624         tn = yaffs_FindLevel0Tnode(dev, &in->variant.fileVariant, chunkInInode);
2625
2626         if (tn) {
2627                 theChunk = yaffs_GetChunkGroupBase(dev,tn,chunkInInode);
2628
2629                 retVal =
2630                     yaffs_FindChunkInGroup(dev, theChunk, tags, in->objectId,
2631                                            chunkInInode);
2632         }
2633         return retVal;
2634 }
2635
2636 static int yaffs_FindAndDeleteChunkInFile(yaffs_Object * in, int chunkInInode,
2637                                           yaffs_ExtendedTags * tags)
2638 {
2639         /* Get the Tnode, then get the level 0 offset chunk offset */
2640         yaffs_Tnode *tn;
2641         int theChunk = -1;
2642         yaffs_ExtendedTags localTags;
2643
2644         yaffs_Device *dev = in->myDev;
2645         int retVal = -1;
2646
2647         if (!tags) {
2648                 /* Passed a NULL, so use our own tags space */
2649                 tags = &localTags;
2650         }
2651
2652         tn = yaffs_FindLevel0Tnode(dev, &in->variant.fileVariant, chunkInInode);
2653
2654         if (tn) {
2655
2656                 theChunk = yaffs_GetChunkGroupBase(dev,tn,chunkInInode);
2657
2658                 retVal =
2659                     yaffs_FindChunkInGroup(dev, theChunk, tags, in->objectId,
2660                                            chunkInInode);
2661
2662                 /* Delete the entry in the filestructure (if found) */
2663                 if (retVal != -1) {
2664                         yaffs_PutLevel0Tnode(dev,tn,chunkInInode,0);
2665                 }
2666         } else {
2667                 /*T(("No level 0 found for %d\n", chunkInInode)); */
2668         }
2669
2670         if (retVal == -1) {
2671                 /* T(("Could not find %d to delete\n",chunkInInode)); */
2672         }
2673         return retVal;
2674 }
2675
2676 #ifdef YAFFS_PARANOID
2677
2678 static int yaffs_CheckFileSanity(yaffs_Object * in)
2679 {
2680         int chunk;
2681         int nChunks;
2682         int fSize;
2683         int failed = 0;
2684         int objId;
2685         yaffs_Tnode *tn;
2686         yaffs_Tags localTags;
2687         yaffs_Tags *tags = &localTags;
2688         int theChunk;
2689         int chunkDeleted;
2690
2691         if (in->variantType != YAFFS_OBJECT_TYPE_FILE) {
2692                 /* T(("Object not a file\n")); */
2693                 return YAFFS_FAIL;
2694         }
2695
2696         objId = in->objectId;
2697         fSize = in->variant.fileVariant.fileSize;
2698         nChunks =
2699             (fSize + in->myDev->nDataBytesPerChunk - 1) / in->myDev->nDataBytesPerChunk;
2700
2701         for (chunk = 1; chunk <= nChunks; chunk++) {
2702                 tn = yaffs_FindLevel0Tnode(in->myDev, &in->variant.fileVariant,
2703                                            chunk);
2704
2705                 if (tn) {
2706
2707                         theChunk = yaffs_GetChunkGroupBase(dev,tn,chunk);
2708
2709                         if (yaffs_CheckChunkBits
2710                             (dev, theChunk / dev->nChunksPerBlock,
2711                              theChunk % dev->nChunksPerBlock)) {
2712
2713                                 yaffs_ReadChunkTagsFromNAND(in->myDev, theChunk,
2714                                                             tags,
2715                                                             &chunkDeleted);
2716                                 if (yaffs_TagsMatch
2717                                     (tags, in->objectId, chunk, chunkDeleted)) {
2718                                         /* found it; */
2719
2720                                 }
2721                         } else {
2722
2723                                 failed = 1;
2724                         }
2725
2726                 } else {
2727                         /* T(("No level 0 found for %d\n", chunk)); */
2728                 }
2729         }
2730
2731         return failed ? YAFFS_FAIL : YAFFS_OK;
2732 }
2733
2734 #endif
2735
2736 static int yaffs_PutChunkIntoFile(yaffs_Object * in, int chunkInInode,
2737                                   int chunkInNAND, int inScan)
2738 {
2739         /* NB inScan is zero unless scanning.
2740          * For forward scanning, inScan is > 0;
2741          * for backward scanning inScan is < 0
2742          */
2743
2744         yaffs_Tnode *tn;
2745         yaffs_Device *dev = in->myDev;
2746         int existingChunk;
2747         yaffs_ExtendedTags existingTags;
2748         yaffs_ExtendedTags newTags;
2749         unsigned existingSerial, newSerial;
2750
2751         if (in->variantType != YAFFS_OBJECT_TYPE_FILE) {
2752                 /* Just ignore an attempt at putting a chunk into a non-file during scanning
2753                  * If it is not during Scanning then something went wrong!
2754                  */
2755                 if (!inScan) {
2756                         T(YAFFS_TRACE_ERROR,
2757                           (TSTR
2758                            ("yaffs tragedy:attempt to put data chunk into a non-file"
2759                             TENDSTR)));
2760                         YBUG();
2761                 }
2762
2763                 yaffs_DeleteChunk(dev, chunkInNAND, 1, __LINE__);
2764                 return YAFFS_OK;
2765         }
2766
2767         tn = yaffs_AddOrFindLevel0Tnode(dev,
2768                                         &in->variant.fileVariant,
2769                                         chunkInInode,
2770                                         NULL);
2771         if (!tn) {
2772                 return YAFFS_FAIL;
2773         }
2774
2775         existingChunk = yaffs_GetChunkGroupBase(dev,tn,chunkInInode);
2776
2777         if (inScan != 0) {
2778                 /* If we're scanning then we need to test for duplicates
2779                  * NB This does not need to be efficient since it should only ever
2780                  * happen when the power fails during a write, then only one
2781                  * chunk should ever be affected.
2782                  *
2783                  * Correction for YAFFS2: This could happen quite a lot and we need to think about efficiency! TODO
2784                  * Update: For backward scanning we don't need to re-read tags so this is quite cheap.
2785                  */
2786
2787                 if (existingChunk != 0) {
2788                         /* NB Right now existing chunk will not be real chunkId if the device >= 32MB
2789                          *    thus we have to do a FindChunkInFile to get the real chunk id.
2790                          *
2791                          * We have a duplicate now we need to decide which one to use:
2792                          *
2793                          * Backwards scanning YAFFS2: The old one is what we use, dump the new one.
2794                          * Forward scanning YAFFS2: The new one is what we use, dump the old one.
2795                          * YAFFS1: Get both sets of tags and compare serial numbers.
2796                          */
2797
2798                         if (inScan > 0) {
2799                                 /* Only do this for forward scanning */
2800                                 yaffs_ReadChunkWithTagsFromNAND(dev,
2801                                                                 chunkInNAND,
2802                                                                 NULL, &newTags);
2803
2804                                 /* Do a proper find */
2805                                 existingChunk =
2806                                     yaffs_FindChunkInFile(in, chunkInInode,
2807                                                           &existingTags);
2808                         }
2809
2810                         if (existingChunk <= 0) {
2811                                 /*Hoosterman - how did this happen? */
2812
2813                                 T(YAFFS_TRACE_ERROR,
2814                                   (TSTR
2815                                    ("yaffs tragedy: existing chunk < 0 in scan"
2816                                     TENDSTR)));
2817
2818                         }
2819
2820                         /* NB The deleted flags should be false, otherwise the chunks will
2821                          * not be loaded during a scan
2822                          */
2823
2824                         newSerial = newTags.serialNumber;
2825                         existingSerial = existingTags.serialNumber;
2826
2827                         if ((inScan > 0) &&
2828                             (in->myDev->isYaffs2 ||
2829                              existingChunk <= 0 ||
2830                              ((existingSerial + 1) & 3) == newSerial)) {
2831                                 /* Forward scanning.
2832                                  * Use new
2833                                  * Delete the old one and drop through to update the tnode
2834                                  */
2835                                 yaffs_DeleteChunk(dev, existingChunk, 1,
2836                                                   __LINE__);
2837                         } else {
2838                                 /* Backward scanning or we want to use the existing one
2839                                  * Use existing.
2840                                  * Delete the new one and return early so that the tnode isn't changed
2841                                  */
2842                                 yaffs_DeleteChunk(dev, chunkInNAND, 1,
2843                                                   __LINE__);
2844                                 return YAFFS_OK;
2845                         }
2846                 }
2847
2848         }
2849
2850         if (existingChunk == 0) {
2851                 in->nDataChunks++;
2852         }
2853
2854         yaffs_PutLevel0Tnode(dev,tn,chunkInInode,chunkInNAND);
2855
2856         return YAFFS_OK;
2857 }
2858
2859 static int yaffs_ReadChunkDataFromObject(yaffs_Object * in, int chunkInInode,
2860                                          __u8 * buffer)
2861 {
2862         int chunkInNAND = yaffs_FindChunkInFile(in, chunkInInode, NULL);
2863
2864         if (chunkInNAND >= 0) {
2865                 return yaffs_ReadChunkWithTagsFromNAND(in->myDev, chunkInNAND,
2866                                                        buffer,NULL);
2867         } else {
2868                 T(YAFFS_TRACE_NANDACCESS,
2869                   (TSTR("Chunk %d not found zero instead" TENDSTR),
2870                    chunkInNAND));
2871                 /* get sane (zero) data if you read a hole */
2872                 memset(buffer, 0, in->myDev->nDataBytesPerChunk);
2873                 return 0;
2874         }
2875
2876 }
2877
2878 void yaffs_DeleteChunk(yaffs_Device * dev, int chunkId, int markNAND, int lyn)
2879 {
2880         int block;
2881         int page;
2882         yaffs_ExtendedTags tags;
2883         yaffs_BlockInfo *bi;
2884
2885         if (chunkId <= 0)
2886                 return;
2887
2888         dev->nDeletions++;
2889         block = chunkId / dev->nChunksPerBlock;
2890         page = chunkId % dev->nChunksPerBlock;
2891
2892         bi = yaffs_GetBlockInfo(dev, block);
2893
2894         T(YAFFS_TRACE_DELETION,
2895           (TSTR("line %d delete of chunk %d" TENDSTR), lyn, chunkId));
2896
2897         if (markNAND &&
2898             bi->blockState != YAFFS_BLOCK_STATE_COLLECTING && !dev->isYaffs2) {
2899
2900                 yaffs_InitialiseTags(&tags);
2901
2902                 tags.chunkDeleted = 1;
2903
2904                 yaffs_WriteChunkWithTagsToNAND(dev, chunkId, NULL, &tags);
2905                 yaffs_HandleUpdateChunk(dev, chunkId, &tags);
2906         } else {
2907                 dev->nUnmarkedDeletions++;
2908         }
2909
2910         /* Pull out of the management area.
2911          * If the whole block became dirty, this will kick off an erasure.
2912          */
2913         if (bi->blockState == YAFFS_BLOCK_STATE_ALLOCATING ||
2914             bi->blockState == YAFFS_BLOCK_STATE_FULL ||
2915             bi->blockState == YAFFS_BLOCK_STATE_NEEDS_SCANNING ||
2916             bi->blockState == YAFFS_BLOCK_STATE_COLLECTING) {
2917                 dev->nFreeChunks++;
2918
2919                 yaffs_ClearChunkBit(dev, block, page);
2920
2921                 bi->pagesInUse--;
2922
2923                 if (bi->pagesInUse == 0 &&
2924                     !bi->hasShrinkHeader &&
2925                     bi->blockState != YAFFS_BLOCK_STATE_ALLOCATING &&
2926                     bi->blockState != YAFFS_BLOCK_STATE_NEEDS_SCANNING) {
2927                         yaffs_BlockBecameDirty(dev, block);
2928                 }
2929
2930         } else {
2931                 /* T(("Bad news deleting chunk %d\n",chunkId)); */
2932         }
2933
2934 }
2935
2936 static int yaffs_WriteChunkDataToObject(yaffs_Object * in, int chunkInInode,
2937                                         const __u8 * buffer, int nBytes,
2938                                         int useReserve)
2939 {
2940         /* Find old chunk Need to do this to get serial number
2941          * Write new one and patch into tree.
2942          * Invalidate old tags.
2943          */
2944
2945         int prevChunkId;
2946         yaffs_ExtendedTags prevTags;
2947
2948         int newChunkId;
2949         yaffs_ExtendedTags newTags;
2950
2951         yaffs_Device *dev = in->myDev;
2952
2953         yaffs_CheckGarbageCollection(dev);
2954
2955         /* Get the previous chunk at this location in the file if it exists */
2956         prevChunkId = yaffs_FindChunkInFile(in, chunkInInode, &prevTags);
2957
2958         /* Set up new tags */
2959         yaffs_InitialiseTags(&newTags);
2960
2961         newTags.chunkId = chunkInInode;
2962         newTags.objectId = in->objectId;
2963         newTags.serialNumber =
2964             (prevChunkId >= 0) ? prevTags.serialNumber + 1 : 1;
2965         newTags.byteCount = nBytes;
2966
2967         newChunkId =
2968             yaffs_WriteNewChunkWithTagsToNAND(dev, buffer, &newTags,
2969                                               useReserve);
2970
2971         if (newChunkId >= 0) {
2972                 yaffs_PutChunkIntoFile(in, chunkInInode, newChunkId, 0);
2973
2974                 if (prevChunkId >= 0) {
2975                         yaffs_DeleteChunk(dev, prevChunkId, 1, __LINE__);
2976
2977                 }
2978
2979                 yaffs_CheckFileSanity(in);
2980         }
2981         return newChunkId;
2982
2983 }
2984
2985 /* UpdateObjectHeader updates the header on NAND for an object.
2986  * If name is not NULL, then that new name is used.
2987  */
2988 int yaffs_UpdateObjectHeader(yaffs_Object * in, const YCHAR * name, int force,
2989                              int isShrink, int shadows)
2990 {
2991
2992         yaffs_BlockInfo *bi;
2993
2994         yaffs_Device *dev = in->myDev;
2995
2996         int prevChunkId;
2997         int retVal = 0;
2998         int result = 0;
2999
3000         int newChunkId;
3001         yaffs_ExtendedTags newTags;
3002
3003         __u8 *buffer = NULL;
3004         YCHAR oldName[YAFFS_MAX_NAME_LENGTH + 1];
3005
3006         yaffs_ObjectHeader *oh = NULL;
3007
3008         if (!in->fake || force) {
3009
3010                 yaffs_CheckGarbageCollection(dev);
3011
3012                 buffer = yaffs_GetTempBuffer(in->myDev, __LINE__);
3013                 oh = (yaffs_ObjectHeader *) buffer;
3014
3015                 prevChunkId = in->chunkId;
3016
3017                 if (prevChunkId >= 0) {
3018                         result = yaffs_ReadChunkWithTagsFromNAND(dev, prevChunkId,
3019                                                         buffer, NULL);
3020                         memcpy(oldName, oh->name, sizeof(oh->name));
3021                 }
3022
3023                 memset(buffer, 0xFF, dev->nDataBytesPerChunk);
3024
3025                 oh->type = in->variantType;
3026                 oh->yst_mode = in->yst_mode;
3027                 oh->shadowsObject = shadows;
3028
3029 #ifdef CONFIG_YAFFS_WINCE
3030                 oh->win_atime[0] = in->win_atime[0];
3031                 oh->win_ctime[0] = in->win_ctime[0];
3032                 oh->win_mtime[0] = in->win_mtime[0];
3033                 oh->win_atime[1] = in->win_atime[1];
3034                 oh->win_ctime[1] = in->win_ctime[1];
3035                 oh->win_mtime[1] = in->win_mtime[1];
3036 #else
3037                 oh->yst_uid = in->yst_uid;
3038                 oh->yst_gid = in->yst_gid;
3039                 oh->yst_atime = in->yst_atime;
3040                 oh->yst_mtime = in->yst_mtime;
3041                 oh->yst_ctime = in->yst_ctime;
3042                 oh->yst_rdev = in->yst_rdev;
3043 #endif
3044                 if (in->parent) {
3045                         oh->parentObjectId = in->parent->objectId;
3046                 } else {
3047                         oh->parentObjectId = 0;
3048                 }
3049
3050                 if (name && *name) {
3051                         memset(oh->name, 0, sizeof(oh->name));
3052                         yaffs_strncpy(oh->name, name, YAFFS_MAX_NAME_LENGTH);
3053                 } else if (prevChunkId) {
3054                         memcpy(oh->name, oldName, sizeof(oh->name));
3055                 } else {
3056                         memset(oh->name, 0, sizeof(oh->name));
3057                 }
3058
3059                 oh->isShrink = isShrink;
3060
3061                 switch (in->variantType) {
3062                 case YAFFS_OBJECT_TYPE_UNKNOWN:
3063                         /* Should not happen */
3064                         break;
3065                 case YAFFS_OBJECT_TYPE_FILE:
3066                         oh->fileSize =
3067                             (oh->parentObjectId == YAFFS_OBJECTID_DELETED
3068                              || oh->parentObjectId ==
3069                              YAFFS_OBJECTID_UNLINKED) ? 0 : in->variant.
3070                             fileVariant.fileSize;
3071                         break;
3072                 case YAFFS_OBJECT_TYPE_HARDLINK:
3073                         oh->equivalentObjectId =
3074                             in->variant.hardLinkVariant.equivalentObjectId;
3075                         break;
3076                 case YAFFS_OBJECT_TYPE_SPECIAL:
3077                         /* Do nothing */
3078                         break;
3079                 case YAFFS_OBJECT_TYPE_DIRECTORY:
3080                         /* Do nothing */
3081                         break;
3082                 case YAFFS_OBJECT_TYPE_SYMLINK:
3083                         yaffs_strncpy(oh->alias,
3084                                       in->variant.symLinkVariant.alias,
3085                                       YAFFS_MAX_ALIAS_LENGTH);
3086                         oh->alias[YAFFS_MAX_ALIAS_LENGTH] = 0;
3087                         break;
3088                 }
3089
3090                 /* Tags */
3091                 yaffs_InitialiseTags(&newTags);
3092                 in->serial++;
3093                 newTags.chunkId = 0;
3094                 newTags.objectId = in->objectId;
3095                 newTags.serialNumber = in->serial;
3096
3097                 /* Add extra info for file header */
3098
3099                 newTags.extraHeaderInfoAvailable = 1;
3100                 newTags.extraParentObjectId = oh->parentObjectId;
3101                 newTags.extraFileLength = oh->fileSize;
3102                 newTags.extraIsShrinkHeader = oh->isShrink;
3103                 newTags.extraEquivalentObjectId = oh->equivalentObjectId;
3104                 newTags.extraShadows = (oh->shadowsObject > 0) ? 1 : 0;
3105                 newTags.extraObjectType = in->variantType;
3106
3107                 /* Create new chunk in NAND */
3108                 newChunkId =
3109                     yaffs_WriteNewChunkWithTagsToNAND(dev, buffer, &newTags,
3110                                                       (prevChunkId >= 0) ? 1 : 0);
3111
3112                 if (newChunkId >= 0) {
3113
3114                         in->chunkId = newChunkId;
3115
3116                         if (prevChunkId >= 0) {
3117                                 yaffs_DeleteChunk(dev, prevChunkId, 1,
3118                                                   __LINE__);
3119                         }
3120
3121                         if(!yaffs_ObjectHasCachedWriteData(in))
3122                                 in->dirty = 0;
3123
3124                         /* If this was a shrink, then mark the block that the chunk lives on */
3125                         if (isShrink) {
3126                                 bi = yaffs_GetBlockInfo(in->myDev,
3127                                                         newChunkId /in->myDev-> nChunksPerBlock);
3128                                 bi->hasShrinkHeader = 1;
3129                         }
3130
3131                 }
3132
3133                 retVal = newChunkId;
3134
3135         }
3136
3137         if (buffer)
3138                 yaffs_ReleaseTempBuffer(dev, buffer, __LINE__);
3139
3140         return retVal;
3141 }
3142
3143 /*------------------------ Short Operations Cache ----------------------------------------
3144  *   In many situations where there is no high level buffering (eg WinCE) a lot of
3145  *   reads might be short sequential reads, and a lot of writes may be short
3146  *   sequential writes. eg. scanning/writing a jpeg file.
3147  *   In these cases, a short read/write cache can provide a huge perfomance benefit
3148  *   with dumb-as-a-rock code.
3149  *   In Linux, the page cache provides read buffering aand the short op cache provides write
3150  *   buffering.
3151  *
3152  *   There are a limited number (~10) of cache chunks per device so that we don't
3153  *   need a very intelligent search.
3154  */
3155
3156 static int yaffs_ObjectHasCachedWriteData(yaffs_Object *obj)
3157 {
3158         yaffs_Device *dev = obj->myDev;
3159         int i;
3160         yaffs_ChunkCache *cache;
3161         int nCaches = obj->myDev->nShortOpCaches;
3162
3163         for(i = 0; i < nCaches; i++){
3164                 cache = &dev->srCache[i];
3165                 if (cache->object == obj &&
3166                     cache->dirty)
3167                         return 1;
3168         }
3169
3170         return 0;
3171 }
3172
3173
3174 static void yaffs_FlushFilesChunkCache(yaffs_Object * obj)
3175 {
3176         yaffs_Device *dev = obj->myDev;
3177         int lowest = -99;       /* Stop compiler whining. */
3178         int i;
3179         yaffs_ChunkCache *cache;
3180         int chunkWritten = 0;
3181         int nCaches = obj->myDev->nShortOpCaches;
3182
3183         if (nCaches > 0) {
3184                 do {
3185                         cache = NULL;
3186
3187                         /* Find the dirty cache for this object with the lowest chunk id. */
3188                         for (i = 0; i < nCaches; i++) {
3189                                 if (dev->srCache[i].object == obj &&
3190                                     dev->srCache[i].dirty) {
3191                                         if (!cache
3192                                             || dev->srCache[i].chunkId <
3193                                             lowest) {
3194                                                 cache = &dev->srCache[i];
3195                                                 lowest = cache->chunkId;
3196                                         }
3197                                 }
3198                         }
3199
3200                         if (cache && !cache->locked) {
3201                                 /* Write it out and free it up */
3202
3203                                 chunkWritten =
3204                                     yaffs_WriteChunkDataToObject(cache->object,
3205                                                                  cache->chunkId,
3206                                                                  cache->data,
3207                                                                  cache->nBytes,
3208                                                                  1);
3209                                 cache->dirty = 0;
3210                                 cache->object = NULL;
3211                         }
3212
3213                 } while (cache && chunkWritten > 0);
3214
3215                 if (cache) {
3216                         /* Hoosterman, disk full while writing cache out. */
3217                         T(YAFFS_TRACE_ERROR,
3218                           (TSTR("yaffs tragedy: no space during cache write" TENDSTR)));
3219
3220                 }
3221         }
3222
3223 }
3224
3225 /*yaffs_FlushEntireDeviceCache(dev)
3226  *
3227  *
3228  */
3229
3230 void yaffs_FlushEntireDeviceCache(yaffs_Device *dev)
3231 {
3232         yaffs_Object *obj;
3233         int nCaches = dev->nShortOpCaches;
3234         int i;
3235
3236         /* Find a dirty object in the cache and flush it...
3237          * until there are no further dirty objects.
3238          */
3239         do {
3240                 obj = NULL;
3241                 for( i = 0; i < nCaches && !obj; i++) {
3242                         if (dev->srCache[i].object &&
3243                             dev->srCache[i].dirty)
3244                                 obj = dev->srCache[i].object;
3245
3246                 }
3247                 if(obj)
3248                         yaffs_FlushFilesChunkCache(obj);
3249
3250         } while(obj);
3251
3252 }
3253
3254
3255 /* Grab us a cache chunk for use.
3256  * First look for an empty one.
3257  * Then look for the least recently used non-dirty one.
3258  * Then look for the least recently used dirty one...., flush and look again.
3259  */
3260 static yaffs_ChunkCache *yaffs_GrabChunkCacheWorker(yaffs_Device * dev)
3261 {
3262         int i;
3263         int usage;
3264         int theOne;
3265
3266         if (dev->nShortOpCaches > 0) {
3267                 for (i = 0; i < dev->nShortOpCaches; i++) {
3268                         if (!dev->srCache[i].object)
3269                                 return &dev->srCache[i];
3270                 }
3271
3272                 return NULL;
3273
3274                 theOne = -1;
3275                 usage = 0;      /* just to stop the compiler grizzling */
3276
3277                 for (i = 0; i < dev->nShortOpCaches; i++) {
3278                         if (!dev->srCache[i].dirty &&
3279                             ((dev->srCache[i].lastUse < usage && theOne >= 0) ||
3280                              theOne < 0)) {
3281                                 usage = dev->srCache[i].lastUse;
3282                                 theOne = i;
3283                         }
3284                 }
3285
3286
3287                 return theOne >= 0 ? &dev->srCache[theOne] : NULL;
3288         } else {
3289                 return NULL;
3290         }
3291
3292 }
3293
3294 static yaffs_ChunkCache *yaffs_GrabChunkCache(yaffs_Device * dev)
3295 {
3296         yaffs_ChunkCache *cache;
3297         yaffs_Object *theObj;
3298         int usage;
3299         int i;
3300         int pushout;
3301
3302         if (dev->nShortOpCaches > 0) {
3303                 /* Try find a non-dirty one... */
3304
3305                 cache = yaffs_GrabChunkCacheWorker(dev);
3306
3307                 if (!cache) {
3308                         /* They were all dirty, find the last recently used object and flush
3309                          * its cache, then  find again.
3310                          * NB what's here is not very accurate, we actually flush the object
3311                          * the last recently used page.
3312                          */
3313
3314                         /* With locking we can't assume we can use entry zero */
3315
3316                         theObj = NULL;
3317                         usage = -1;
3318                         cache = NULL;
3319                         pushout = -1;
3320
3321                         for (i = 0; i < dev->nShortOpCaches; i++) {
3322                                 if (dev->srCache[i].object &&
3323                                     !dev->srCache[i].locked &&
3324                                     (dev->srCache[i].lastUse < usage || !cache))
3325                                 {
3326                                         usage = dev->srCache[i].lastUse;
3327                                         theObj = dev->srCache[i].object;
3328                                         cache = &dev->srCache[i];
3329                                         pushout = i;
3330                                 }
3331                         }
3332
3333                         if (!cache || cache->dirty) {
3334                                 /* Flush and try again */
3335                                 yaffs_FlushFilesChunkCache(theObj);
3336                                 cache = yaffs_GrabChunkCacheWorker(dev);
3337                         }
3338
3339                 }
3340                 return cache;
3341         } else
3342                 return NULL;
3343
3344 }
3345
3346 /* Find a cached chunk */
3347 static yaffs_ChunkCache *yaffs_FindChunkCache(const yaffs_Object * obj,
3348                                               int chunkId)
3349 {
3350         yaffs_Device *dev = obj->myDev;
3351         int i;
3352         if (dev->nShortOpCaches > 0) {
3353                 for (i = 0; i < dev->nShortOpCaches; i++) {
3354                         if (dev->srCache[i].object == obj &&
3355                             dev->srCache[i].chunkId == chunkId) {
3356                                 dev->cacheHits++;
3357
3358                                 return &dev->srCache[i];
3359                         }
3360                 }
3361         }
3362         return NULL;
3363 }
3364
3365 /* Mark the chunk for the least recently used algorithym */
3366 static void yaffs_UseChunkCache(yaffs_Device * dev, yaffs_ChunkCache * cache,
3367                                 int isAWrite)
3368 {
3369
3370         if (dev->nShortOpCaches > 0) {
3371                 if (dev->srLastUse < 0 || dev->srLastUse > 100000000) {
3372                         /* Reset the cache usages */
3373                         int i;
3374                         for (i = 1; i < dev->nShortOpCaches; i++) {
3375                                 dev->srCache[i].lastUse = 0;
3376                         }
3377                         dev->srLastUse = 0;
3378                 }
3379
3380                 dev->srLastUse++;
3381
3382                 cache->lastUse = dev->srLastUse;
3383
3384                 if (isAWrite) {
3385                         cache->dirty = 1;
3386                 }
3387         }
3388 }
3389
3390 /* Invalidate a single cache page.
3391  * Do this when a whole page gets written,
3392  * ie the short cache for this page is no longer valid.
3393  */
3394 static void yaffs_InvalidateChunkCache(yaffs_Object * object, int chunkId)
3395 {
3396         if (object->myDev->nShortOpCaches > 0) {
3397                 yaffs_ChunkCache *cache = yaffs_FindChunkCache(object, chunkId);
3398
3399                 if (cache) {
3400                         cache->object = NULL;
3401                 }
3402         }
3403 }
3404
3405 /* Invalidate all the cache pages associated with this object
3406  * Do this whenever ther file is deleted or resized.
3407  */
3408 static void yaffs_InvalidateWholeChunkCache(yaffs_Object * in)
3409 {
3410         int i;
3411         yaffs_Device *dev = in->myDev;
3412
3413         if (dev->nShortOpCaches > 0) {
3414                 /* Invalidate it. */
3415                 for (i = 0; i < dev->nShortOpCaches; i++) {
3416                         if (dev->srCache[i].object == in) {
3417                                 dev->srCache[i].object = NULL;
3418                         }
3419                 }
3420         }
3421 }
3422
3423 /*--------------------- Checkpointing --------------------*/
3424
3425
3426 static int yaffs_WriteCheckpointValidityMarker(yaffs_Device *dev,int head)
3427 {
3428         yaffs_CheckpointValidity cp;
3429         cp.structType = sizeof(cp);
3430         cp.magic = YAFFS_MAGIC;
3431         cp.version = YAFFS_CHECKPOINT_VERSION;
3432         cp.head = (head) ? 1 : 0;
3433
3434         return (yaffs_CheckpointWrite(dev,&cp,sizeof(cp)) == sizeof(cp))?
3435                 1 : 0;
3436 }
3437
3438 static int yaffs_ReadCheckpointValidityMarker(yaffs_Device *dev, int head)
3439 {
3440         yaffs_CheckpointValidity cp;
3441         int ok;
3442
3443         ok = (yaffs_CheckpointRead(dev,&cp,sizeof(cp)) == sizeof(cp));
3444
3445         if(ok)
3446                 ok = (cp.structType == sizeof(cp)) &&
3447                      (cp.magic == YAFFS_MAGIC) &&
3448                      (cp.version == YAFFS_CHECKPOINT_VERSION) &&
3449                      (cp.head == ((head) ? 1 : 0));
3450         return ok ? 1 : 0;
3451 }
3452
3453 static void yaffs_DeviceToCheckpointDevice(yaffs_CheckpointDevice *cp,
3454                                            yaffs_Device *dev)
3455 {
3456         cp->nErasedBlocks = dev->nErasedBlocks;
3457         cp->allocationBlock = dev->allocationBlock;
3458         cp->allocationPage = dev->allocationPage;
3459         cp->nFreeChunks = dev->nFreeChunks;
3460
3461         cp->nDeletedFiles = dev->nDeletedFiles;
3462         cp->nUnlinkedFiles = dev->nUnlinkedFiles;
3463         cp->nBackgroundDeletions = dev->nBackgroundDeletions;
3464         cp->sequenceNumber = dev->sequenceNumber;
3465         cp->oldestDirtySequence = dev->oldestDirtySequence;
3466
3467 }
3468
3469 static void yaffs_CheckpointDeviceToDevice(yaffs_Device *dev,
3470                                            yaffs_CheckpointDevice *cp)
3471 {
3472         dev->nErasedBlocks = cp->nErasedBlocks;
3473         dev->allocationBlock = cp->allocationBlock;
3474         dev->allocationPage = cp->allocationPage;
3475         dev->nFreeChunks = cp->nFreeChunks;
3476
3477         dev->nDeletedFiles = cp->nDeletedFiles;
3478         dev->nUnlinkedFiles = cp->nUnlinkedFiles;
3479         dev->nBackgroundDeletions = cp->nBackgroundDeletions;
3480         dev->sequenceNumber = cp->sequenceNumber;
3481         dev->oldestDirtySequence = cp->oldestDirtySequence;
3482 }
3483
3484
3485 static int yaffs_WriteCheckpointDevice(yaffs_Device *dev)
3486 {
3487         yaffs_CheckpointDevice cp;
3488         __u32 nBytes;
3489         __u32 nBlocks = (dev->internalEndBlock - dev->internalStartBlock + 1);
3490
3491         int ok;
3492
3493         /* Write device runtime values*/
3494         yaffs_DeviceToCheckpointDevice(&cp,dev);
3495         cp.structType = sizeof(cp);
3496
3497         ok = (yaffs_CheckpointWrite(dev,&cp,sizeof(cp)) == sizeof(cp));
3498
3499         /* Write block info */
3500         if(ok) {
3501                 nBytes = nBlocks * sizeof(yaffs_BlockInfo);
3502                 ok = (yaffs_CheckpointWrite(dev,dev->blockInfo,nBytes) == nBytes);
3503         }
3504
3505         /* Write chunk bits */
3506         if(ok) {
3507                 nBytes = nBlocks * dev->chunkBitmapStride;
3508                 ok = (yaffs_CheckpointWrite(dev,dev->chunkBits,nBytes) == nBytes);
3509         }
3510         return   ok ? 1 : 0;
3511
3512 }
3513
3514 static int yaffs_ReadCheckpointDevice(yaffs_Device *dev)
3515 {
3516         yaffs_CheckpointDevice cp;
3517         __u32 nBytes;
3518         __u32 nBlocks = (dev->internalEndBlock - dev->internalStartBlock + 1);
3519
3520         int ok;
3521
3522         ok = (yaffs_CheckpointRead(dev,&cp,sizeof(cp)) == sizeof(cp));
3523         if(!ok)
3524                 return 0;
3525
3526         if(cp.structType != sizeof(cp))
3527                 return 0;
3528
3529
3530         yaffs_CheckpointDeviceToDevice(dev,&cp);
3531
3532         nBytes = nBlocks * sizeof(yaffs_BlockInfo);
3533
3534         ok = (yaffs_CheckpointRead(dev,dev->blockInfo,nBytes) == nBytes);
3535
3536         if(!ok)
3537                 return 0;
3538         nBytes = nBlocks * dev->chunkBitmapStride;
3539
3540         ok = (yaffs_CheckpointRead(dev,dev->chunkBits,nBytes) == nBytes);
3541
3542         return ok ? 1 : 0;
3543 }
3544
3545 static void yaffs_ObjectToCheckpointObject(yaffs_CheckpointObject *cp,
3546                                            yaffs_Object *obj)
3547 {
3548
3549         cp->objectId = obj->objectId;
3550         cp->parentId = (obj->parent) ? obj->parent->objectId : 0;
3551         cp->chunkId = obj->chunkId;
3552         cp->variantType = obj->variantType;
3553         cp->deleted = obj->deleted;
3554         cp->softDeleted = obj->softDeleted;
3555         cp->unlinked = obj->unlinked;
3556         cp->fake = obj->fake;
3557         cp->renameAllowed = obj->renameAllowed;
3558         cp->unlinkAllowed = obj->unlinkAllowed;
3559         cp->serial = obj->serial;
3560         cp->nDataChunks = obj->nDataChunks;
3561
3562         if(obj->variantType == YAFFS_OBJECT_TYPE_FILE)
3563                 cp->fileSizeOrEquivalentObjectId = obj->variant.fileVariant.fileSize;
3564         else if(obj->variantType == YAFFS_OBJECT_TYPE_HARDLINK)
3565                 cp->fileSizeOrEquivalentObjectId = obj->variant.hardLinkVariant.equivalentObjectId;
3566 }
3567
3568 static void yaffs_CheckpointObjectToObject( yaffs_Object *obj,yaffs_CheckpointObject *cp)
3569 {
3570
3571         yaffs_Object *parent;
3572
3573         obj->objectId = cp->objectId;
3574
3575         if(cp->parentId)
3576                 parent = yaffs_FindOrCreateObjectByNumber(
3577                                         obj->myDev,
3578                                         cp->parentId,
3579                                         YAFFS_OBJECT_TYPE_DIRECTORY);
3580         else
3581                 parent = NULL;
3582
3583         if(parent)
3584                 yaffs_AddObjectToDirectory(parent, obj);
3585
3586         obj->chunkId = cp->chunkId;
3587         obj->variantType = cp->variantType;
3588         obj->deleted = cp->deleted;
3589         obj->softDeleted = cp->softDeleted;
3590         obj->unlinked = cp->unlinked;
3591         obj->fake = cp->fake;
3592         obj->renameAllowed = cp->renameAllowed;
3593         obj->unlinkAllowed = cp->unlinkAllowed;
3594         obj->serial = cp->serial;
3595         obj->nDataChunks = cp->nDataChunks;
3596
3597         if(obj->variantType == YAFFS_OBJECT_TYPE_FILE)
3598                 obj->variant.fileVariant.fileSize = cp->fileSizeOrEquivalentObjectId;
3599         else if(obj->variantType == YAFFS_OBJECT_TYPE_HARDLINK)
3600                 obj->variant.hardLinkVariant.equivalentObjectId = cp->fileSizeOrEquivalentObjectId;
3601
3602         if(obj->objectId >= YAFFS_NOBJECT_BUCKETS)
3603                 obj->lazyLoaded = 1;
3604 }
3605
3606
3607
3608 static int yaffs_CheckpointTnodeWorker(yaffs_Object * in, yaffs_Tnode * tn,
3609                                         __u32 level, int chunkOffset)
3610 {
3611         int i;
3612         yaffs_Device *dev = in->myDev;
3613         int ok = 1;
3614         int nTnodeBytes = (dev->tnodeWidth * YAFFS_NTNODES_LEVEL0)/8;
3615
3616         if (tn) {
3617                 if (level > 0) {
3618
3619                         for (i = 0; i < YAFFS_NTNODES_INTERNAL && ok; i++){
3620                                 if (tn->internal[i]) {
3621                                         ok = yaffs_CheckpointTnodeWorker(in,
3622                                                         tn->internal[i],
3623                                                         level - 1,
3624                                                         (chunkOffset<<YAFFS_TNODES_INTERNAL_BITS) + i);
3625                                 }
3626                         }
3627                 } else if (level == 0) {
3628                         __u32 baseOffset = chunkOffset <<  YAFFS_TNODES_LEVEL0_BITS;
3629                         /* printf("write tnode at %d\n",baseOffset); */
3630                         ok = (yaffs_CheckpointWrite(dev,&baseOffset,sizeof(baseOffset)) == sizeof(baseOffset));
3631                         if(ok)
3632                                 ok = (yaffs_CheckpointWrite(dev,tn,nTnodeBytes) == nTnodeBytes);
3633                 }
3634         }
3635
3636         return ok;
3637
3638 }
3639
3640 static int yaffs_WriteCheckpointTnodes(yaffs_Object *obj)
3641 {
3642         __u32 endMarker = ~0;
3643         int ok = 1;
3644
3645         if(obj->variantType == YAFFS_OBJECT_TYPE_FILE){
3646                 ok = yaffs_CheckpointTnodeWorker(obj,
3647                                             obj->variant.fileVariant.top,
3648                                             obj->variant.fileVariant.topLevel,
3649                                             0);
3650                 if(ok)
3651                         ok = (yaffs_CheckpointWrite(obj->myDev,&endMarker,sizeof(endMarker)) ==
3652                                 sizeof(endMarker));
3653         }
3654
3655         return ok ? 1 : 0;
3656 }
3657
3658 static int yaffs_ReadCheckpointTnodes(yaffs_Object *obj)
3659 {
3660         __u32 baseChunk;
3661         int ok = 1;
3662         yaffs_Device *dev = obj->myDev;
3663         yaffs_FileStructure *fileStructPtr = &obj->variant.fileVariant;
3664         yaffs_Tnode *tn;
3665
3666         ok = (yaffs_CheckpointRead(dev,&baseChunk,sizeof(baseChunk)) == sizeof(baseChunk));
3667
3668         while(ok && (~baseChunk)){
3669                 /* Read level 0 tnode */
3670
3671                 /* printf("read  tnode at %d\n",baseChunk); */
3672                 tn = yaffs_GetTnodeRaw(dev);
3673                 if(tn)
3674                         ok = (yaffs_CheckpointRead(dev,tn,(dev->tnodeWidth * YAFFS_NTNODES_LEVEL0)/8) ==
3675                               (dev->tnodeWidth * YAFFS_NTNODES_LEVEL0)/8);
3676                 else
3677                         ok = 0;
3678
3679                 if(tn && ok){
3680                         ok = yaffs_AddOrFindLevel0Tnode(dev,
3681                                                         fileStructPtr,
3682                                                         baseChunk,
3683                                                         tn) ? 1 : 0;
3684                 }
3685
3686                 if(ok)
3687                         ok = (yaffs_CheckpointRead(dev,&baseChunk,sizeof(baseChunk)) == sizeof(baseChunk));
3688
3689         }
3690
3691         return ok ? 1 : 0;
3692 }
3693
3694
3695 static int yaffs_WriteCheckpointObjects(yaffs_Device *dev)
3696 {
3697         yaffs_Object *obj;
3698         yaffs_CheckpointObject cp;
3699         int i;
3700         int ok = 1;
3701         struct list_head *lh;
3702
3703
3704         /* Iterate through the objects in each hash entry,
3705          * dumping them to the checkpointing stream.
3706          */
3707
3708          for(i = 0; ok &&  i <  YAFFS_NOBJECT_BUCKETS; i++){
3709                 list_for_each(lh, &dev->objectBucket[i].list) {
3710                         if (lh) {
3711                                 obj = list_entry(lh, yaffs_Object, hashLink);
3712                                 if (!obj->deferedFree) {
3713                                         yaffs_ObjectToCheckpointObject(&cp,obj);
3714                                         cp.structType = sizeof(cp);
3715                                         /* printf("Write out object %d type %d\n",obj->objectId,obj->variantType); */
3716                                         ok = (yaffs_CheckpointWrite(dev,&cp,sizeof(cp)) == sizeof(cp));
3717
3718                                         if(ok && obj->variantType == YAFFS_OBJECT_TYPE_FILE){
3719                                                 ok = yaffs_WriteCheckpointTnodes(obj);
3720                                         }
3721                                 }
3722                         }
3723                 }
3724          }
3725
3726          /* Dump end of list */
3727         memset(&cp,0xFF,sizeof(yaffs_CheckpointObject));
3728         cp.structType = sizeof(cp);
3729
3730         if(ok)
3731                 ok = (yaffs_CheckpointWrite(dev,&cp,sizeof(cp)) == sizeof(cp));
3732
3733         return ok ? 1 : 0;
3734 }
3735
3736 static int yaffs_ReadCheckpointObjects(yaffs_Device *dev)
3737 {
3738         yaffs_Object *obj;
3739         yaffs_CheckpointObject cp;
3740         int ok = 1;
3741         int done = 0;
3742         yaffs_Object *hardList = NULL;
3743
3744         while(ok && !done) {
3745                 ok = (yaffs_CheckpointRead(dev,&cp,sizeof(cp)) == sizeof(cp));
3746                 if(cp.structType != sizeof(cp)) {
3747                         /* printf("structure parsing failed\n"); */
3748                         ok = 0;
3749                 }
3750
3751                 if(ok && cp.objectId == ~0)
3752                         done = 1;
3753                 else if(ok){
3754                         T(YAFFS_TRACE_CHECKPOINT,(TSTR("Read object %d parent %d type %d" TENDSTR),
3755                                 cp.objectId,cp.parentId,cp.variantType));
3756                         obj = yaffs_FindOrCreateObjectByNumber(dev,cp.objectId, cp.variantType);
3757                         if(obj) {
3758                                 yaffs_CheckpointObjectToObject(obj,&cp);
3759                                 if(obj->variantType == YAFFS_OBJECT_TYPE_FILE) {
3760                                         ok = yaffs_ReadCheckpointTnodes(obj);
3761                                 } else if(obj->variantType == YAFFS_OBJECT_TYPE_HARDLINK) {
3762                                         obj->hardLinks.next =
3763                                                     (struct list_head *)
3764                                                     hardList;
3765                                         hardList = obj;
3766                                 }
3767
3768                         }
3769                 }
3770         }
3771
3772         if(ok)
3773                 yaffs_HardlinkFixup(dev,hardList);
3774
3775         return ok ? 1 : 0;
3776 }
3777
3778 static int yaffs_WriteCheckpointData(yaffs_Device *dev)
3779 {
3780
3781         int ok;
3782
3783         ok = yaffs_CheckpointOpen(dev,1);
3784
3785         if(ok)
3786                 ok = yaffs_WriteCheckpointValidityMarker(dev,1);
3787         if(ok)
3788                 ok = yaffs_WriteCheckpointDevice(dev);
3789         if(ok)
3790                 ok = yaffs_WriteCheckpointObjects(dev);
3791         if(ok)
3792                 ok = yaffs_WriteCheckpointValidityMarker(dev,0);
3793
3794         if(!yaffs_CheckpointClose(dev))
3795                  ok = 0;
3796
3797         if(ok)
3798                 dev->isCheckpointed = 1;
3799          else
3800                 dev->isCheckpointed = 0;
3801
3802         return dev->isCheckpointed;
3803 }
3804
3805 static int yaffs_ReadCheckpointData(yaffs_Device *dev)
3806 {
3807         int ok;
3808
3809         ok = yaffs_CheckpointOpen(dev,0); /* open for read */
3810
3811         if(ok)
3812                 ok = yaffs_ReadCheckpointValidityMarker(dev,1);
3813         if(ok)
3814                 ok = yaffs_ReadCheckpointDevice(dev);
3815         if(ok)
3816                 ok = yaffs_ReadCheckpointObjects(dev);
3817         if(ok)
3818                 ok = yaffs_ReadCheckpointValidityMarker(dev,0);
3819
3820
3821
3822         if(!yaffs_CheckpointClose(dev))
3823                 ok = 0;
3824
3825         if(ok)
3826                 dev->isCheckpointed = 1;
3827          else
3828                 dev->isCheckpointed = 0;
3829
3830         return ok ? 1 : 0;
3831
3832 }
3833
3834 static void yaffs_InvalidateCheckpoint(yaffs_Device *dev)
3835 {
3836         if(dev->isCheckpointed ||
3837            dev->blocksInCheckpoint > 0){
3838                 dev->isCheckpointed = 0;
3839                 yaffs_CheckpointInvalidateStream(dev);
3840                 if(dev->superBlock && dev->markSuperBlockDirty)
3841                         dev->markSuperBlockDirty(dev->superBlock);
3842         }
3843 }
3844
3845
3846 int yaffs_CheckpointSave(yaffs_Device *dev)
3847 {
3848         T(YAFFS_TRACE_CHECKPOINT,(TSTR("save entry: isCheckpointed %d"TENDSTR),dev->isCheckpointed));
3849
3850         if(!dev->isCheckpointed)
3851                 yaffs_WriteCheckpointData(dev);
3852
3853         T(YAFFS_TRACE_CHECKPOINT,(TSTR("save exit: isCheckpointed %d"TENDSTR),dev->isCheckpointed));
3854
3855         return dev->isCheckpointed;
3856 }
3857
3858 int yaffs_CheckpointRestore(yaffs_Device *dev)
3859 {
3860         int retval;
3861         T(YAFFS_TRACE_CHECKPOINT,(TSTR("restore entry: isCheckpointed %d"TENDSTR),dev->isCheckpointed));
3862
3863         retval = yaffs_ReadCheckpointData(dev);
3864
3865         T(YAFFS_TRACE_CHECKPOINT,(TSTR("restore exit: isCheckpointed %d"TENDSTR),dev->isCheckpointed));
3866
3867         return retval;
3868 }
3869
3870 /*--------------------- File read/write ------------------------
3871  * Read and write have very similar structures.
3872  * In general the read/write has three parts to it
3873  * An incomplete chunk to start with (if the read/write is not chunk-aligned)
3874  * Some complete chunks
3875  * An incomplete chunk to end off with
3876  *
3877  * Curve-balls: the first chunk might also be the last chunk.
3878  */
3879
3880 int yaffs_ReadDataFromFile(yaffs_Object * in, __u8 * buffer, loff_t offset,
3881                            int nBytes)
3882 {
3883
3884         int chunk;
3885         int start;
3886         int nToCopy;
3887         int n = nBytes;
3888         int nDone = 0;
3889         yaffs_ChunkCache *cache;
3890
3891         yaffs_Device *dev;
3892
3893         dev = in->myDev;
3894
3895         while (n > 0) {
3896                 //chunk = offset / dev->nDataBytesPerChunk + 1;
3897                 //start = offset % dev->nDataBytesPerChunk;
3898                 yaffs_AddrToChunk(dev,offset,&chunk,&start);
3899                 chunk++;
3900
3901                 /* OK now check for the curveball where the start and end are in
3902                  * the same chunk.
3903                  */
3904                 if ((start + n) < dev->nDataBytesPerChunk) {
3905                         nToCopy = n;
3906                 } else {
3907                         nToCopy = dev->nDataBytesPerChunk - start;
3908                 }
3909
3910                 cache = yaffs_FindChunkCache(in, chunk);
3911
3912                 /* If the chunk is already in the cache or it is less than a whole chunk
3913                  * then use the cache (if there is caching)
3914                  * else bypass the cache.
3915                  */
3916                 if (cache || nToCopy != dev->nDataBytesPerChunk) {
3917                         if (dev->nShortOpCaches > 0) {
3918
3919                                 /* If we can't find the data in the cache, then load it up. */
3920
3921                                 if (!cache) {
3922                                         cache = yaffs_GrabChunkCache(in->myDev);
3923                                         cache->object = in;
3924                                         cache->chunkId = chunk;
3925                                         cache->dirty = 0;
3926                                         cache->locked = 0;
3927                                         yaffs_ReadChunkDataFromObject(in, chunk,
3928                                                                       cache->
3929                                                                       data);
3930                                         cache->nBytes = 0;
3931                                 }
3932
3933                                 yaffs_UseChunkCache(dev, cache, 0);
3934
3935                                 cache->locked = 1;
3936
3937 #ifdef CONFIG_YAFFS_WINCE
3938                                 yfsd_UnlockYAFFS(TRUE);
3939 #endif
3940                                 memcpy(buffer, &cache->data[start], nToCopy);
3941
3942 #ifdef CONFIG_YAFFS_WINCE
3943                                 yfsd_LockYAFFS(TRUE);
3944 #endif
3945                                 cache->locked = 0;
3946                         } else {
3947                                 /* Read into the local buffer then copy..*/
3948
3949                                 __u8 *localBuffer =
3950                                     yaffs_GetTempBuffer(dev, __LINE__);
3951                                 yaffs_ReadChunkDataFromObject(in, chunk,
3952                                                               localBuffer);
3953 #ifdef CONFIG_YAFFS_WINCE
3954                                 yfsd_UnlockYAFFS(TRUE);
3955 #endif
3956                                 memcpy(buffer, &localBuffer[start], nToCopy);
3957
3958 #ifdef CONFIG_YAFFS_WINCE
3959                                 yfsd_LockYAFFS(TRUE);
3960 #endif
3961                                 yaffs_ReleaseTempBuffer(dev, localBuffer,
3962                                                         __LINE__);
3963                         }
3964
3965                 } else {
3966 #ifdef CONFIG_YAFFS_WINCE
3967                         __u8 *localBuffer = yaffs_GetTempBuffer(dev, __LINE__);
3968
3969                         /* Under WinCE can't do direct transfer. Need to use a local buffer.
3970                          * This is because we otherwise screw up WinCE's memory mapper
3971                          */
3972                         yaffs_ReadChunkDataFromObject(in, chunk, localBuffer);
3973
3974 #ifdef CONFIG_YAFFS_WINCE
3975                         yfsd_UnlockYAFFS(TRUE);
3976 #endif
3977                         memcpy(buffer, localBuffer, dev->nDataBytesPerChunk);
3978
3979 #ifdef CONFIG_YAFFS_WINCE
3980                         yfsd_LockYAFFS(TRUE);
3981                         yaffs_ReleaseTempBuffer(dev, localBuffer, __LINE__);
3982 #endif
3983
3984 #else
3985                         /* A full chunk. Read directly into the supplied buffer. */
3986                         yaffs_ReadChunkDataFromObject(in, chunk, buffer);
3987 #endif
3988                 }
3989
3990                 n -= nToCopy;
3991                 offset += nToCopy;
3992                 buffer += nToCopy;
3993                 nDone += nToCopy;
3994
3995         }
3996
3997         return nDone;
3998 }
3999
4000 int yaffs_WriteDataToFile(yaffs_Object * in, const __u8 * buffer, loff_t offset,
4001                           int nBytes, int writeThrough)
4002 {
4003
4004         int chunk;
4005         int start;
4006         int nToCopy;
4007         int n = nBytes;
4008         int nDone = 0;
4009         int nToWriteBack;
4010         int startOfWrite = offset;
4011         int chunkWritten = 0;
4012         int nBytesRead;
4013
4014         yaffs_Device *dev;
4015
4016         dev = in->myDev;
4017
4018         while (n > 0 && chunkWritten >= 0) {
4019                 //chunk = offset / dev->nDataBytesPerChunk + 1;
4020                 //start = offset % dev->nDataBytesPerChunk;
4021                 yaffs_AddrToChunk(dev,offset,&chunk,&start);
4022                 chunk++;
4023
4024                 /* OK now check for the curveball where the start and end are in
4025                  * the same chunk.
4026                  */
4027
4028                 if ((start + n) < dev->nDataBytesPerChunk) {
4029                         nToCopy = n;
4030
4031                         /* Now folks, to calculate how many bytes to write back....
4032                          * If we're overwriting and not writing to then end of file then
4033                          * we need to write back as much as was there before.
4034                          */
4035
4036                         nBytesRead =
4037                             in->variant.fileVariant.fileSize -
4038                             ((chunk - 1) * dev->nDataBytesPerChunk);
4039
4040                         if (nBytesRead > dev->nDataBytesPerChunk) {
4041                                 nBytesRead = dev->nDataBytesPerChunk;
4042                         }
4043
4044                         nToWriteBack =
4045                             (nBytesRead >
4046                              (start + n)) ? nBytesRead : (start + n);
4047
4048                 } else {
4049                         nToCopy = dev->nDataBytesPerChunk - start;
4050                         nToWriteBack = dev->nDataBytesPerChunk;
4051                 }
4052
4053                 if (nToCopy != dev->nDataBytesPerChunk) {
4054                         /* An incomplete start or end chunk (or maybe both start and end chunk) */
4055                         if (dev->nShortOpCaches > 0) {
4056                                 yaffs_ChunkCache *cache;
4057                                 /* If we can't find the data in the cache, then load the cache */
4058                                 cache = yaffs_FindChunkCache(in, chunk);
4059
4060                                 if (!cache
4061                                     && yaffs_CheckSpaceForAllocation(in->
4062                                                                      myDev)) {
4063                                         cache = yaffs_GrabChunkCache(in->myDev);
4064                                         cache->object = in;
4065                                         cache->chunkId = chunk;
4066                                         cache->dirty = 0;
4067                                         cache->locked = 0;
4068                                         yaffs_ReadChunkDataFromObject(in, chunk,
4069                                                                       cache->
4070                                                                       data);
4071                                 }
4072                                 else if(cache &&
4073                                         !cache->dirty &&
4074                                         !yaffs_CheckSpaceForAllocation(in->myDev)){
4075                                         /* Drop the cache if it was a read cache item and
4076                                          * no space check has been made for it.
4077                                          */
4078                                          cache = NULL;
4079                                 }
4080
4081                                 if (cache) {
4082                                         yaffs_UseChunkCache(dev, cache, 1);
4083                                         cache->locked = 1;
4084 #ifdef CONFIG_YAFFS_WINCE
4085                                         yfsd_UnlockYAFFS(TRUE);
4086 #endif
4087
4088                                         memcpy(&cache->data[start], buffer,
4089                                                nToCopy);
4090
4091 #ifdef CONFIG_YAFFS_WINCE
4092                                         yfsd_LockYAFFS(TRUE);
4093 #endif
4094                                         cache->locked = 0;
4095                                         cache->nBytes = nToWriteBack;
4096
4097                                         if (writeThrough) {
4098                                                 chunkWritten =
4099                                                     yaffs_WriteChunkDataToObject
4100                                                     (cache->object,
4101                                                      cache->chunkId,
4102                                                      cache->data, cache->nBytes,
4103                                                      1);
4104                                                 cache->dirty = 0;
4105                                         }
4106
4107                                 } else {
4108                                         chunkWritten = -1;      /* fail the write */
4109                                 }
4110                         } else {
4111                                 /* An incomplete start or end chunk (or maybe both start and end chunk)
4112                                  * Read into the local buffer then copy, then copy over and write back.
4113                                  */
4114
4115                                 __u8 *localBuffer =
4116                                     yaffs_GetTempBuffer(dev, __LINE__);
4117
4118                                 yaffs_ReadChunkDataFromObject(in, chunk,
4119                                                               localBuffer);
4120
4121 #ifdef CONFIG_YAFFS_WINCE
4122                                 yfsd_UnlockYAFFS(TRUE);
4123 #endif
4124
4125                                 memcpy(&localBuffer[start], buffer, nToCopy);
4126
4127 #ifdef CONFIG_YAFFS_WINCE
4128                                 yfsd_LockYAFFS(TRUE);
4129 #endif
4130                                 chunkWritten =
4131                                     yaffs_WriteChunkDataToObject(in, chunk,
4132                                                                  localBuffer,
4133                                                                  nToWriteBack,
4134                                                                  0);
4135
4136                                 yaffs_ReleaseTempBuffer(dev, localBuffer,
4137                                                         __LINE__);
4138
4139                         }
4140
4141                 } else {
4142
4143 #ifdef CONFIG_YAFFS_WINCE
4144                         /* Under WinCE can't do direct transfer. Need to use a local buffer.
4145                          * This is because we otherwise screw up WinCE's memory mapper
4146                          */
4147                         __u8 *localBuffer = yaffs_GetTempBuffer(dev, __LINE__);
4148 #ifdef CONFIG_YAFFS_WINCE
4149                         yfsd_UnlockYAFFS(TRUE);
4150 #endif
4151                         memcpy(localBuffer, buffer, dev->nDataBytesPerChunk);
4152 #ifdef CONFIG_YAFFS_WINCE
4153                         yfsd_LockYAFFS(TRUE);
4154 #endif
4155                         chunkWritten =
4156                             yaffs_WriteChunkDataToObject(in, chunk, localBuffer,
4157                                                          dev->nDataBytesPerChunk,
4158                                                          0);
4159                         yaffs_ReleaseTempBuffer(dev, localBuffer, __LINE__);
4160 #else
4161                         /* A full chunk. Write directly from the supplied buffer. */
4162                         chunkWritten =
4163                             yaffs_WriteChunkDataToObject(in, chunk, buffer,
4164                                                          dev->nDataBytesPerChunk,
4165                                                          0);
4166 #endif
4167                         /* Since we've overwritten the cached data, we better invalidate it. */
4168                         yaffs_InvalidateChunkCache(in, chunk);
4169                 }
4170
4171                 if (chunkWritten >= 0) {
4172                         n -= nToCopy;
4173                         offset += nToCopy;
4174                         buffer += nToCopy;
4175                         nDone += nToCopy;
4176                 }
4177
4178         }
4179
4180         /* Update file object */
4181
4182         if ((startOfWrite + nDone) > in->variant.fileVariant.fileSize) {
4183                 in->variant.fileVariant.fileSize = (startOfWrite + nDone);
4184         }
4185
4186         in->dirty = 1;
4187
4188         return nDone;
4189 }
4190
4191
4192 /* ---------------------- File resizing stuff ------------------ */
4193
4194 static void yaffs_PruneResizedChunks(yaffs_Object * in, int newSize)
4195 {
4196
4197         yaffs_Device *dev = in->myDev;
4198         int oldFileSize = in->variant.fileVariant.fileSize;
4199
4200         int lastDel = 1 + (oldFileSize - 1) / dev->nDataBytesPerChunk;
4201
4202         int startDel = 1 + (newSize + dev->nDataBytesPerChunk - 1) /
4203             dev->nDataBytesPerChunk;
4204         int i;
4205         int chunkId;
4206
4207         /* Delete backwards so that we don't end up with holes if
4208          * power is lost part-way through the operation.
4209          */
4210         for (i = lastDel; i >= startDel; i--) {
4211                 /* NB this could be optimised somewhat,
4212                  * eg. could retrieve the tags and write them without
4213                  * using yaffs_DeleteChunk
4214                  */
4215
4216                 chunkId = yaffs_FindAndDeleteChunkInFile(in, i, NULL);
4217                 if (chunkId > 0) {
4218                         if (chunkId <
4219                             (dev->internalStartBlock * dev->nChunksPerBlock)
4220                             || chunkId >=
4221                             ((dev->internalEndBlock +
4222                               1) * dev->nChunksPerBlock)) {
4223                                 T(YAFFS_TRACE_ALWAYS,
4224                                   (TSTR("Found daft chunkId %d for %d" TENDSTR),
4225                                    chunkId, i));
4226                         } else {
4227                                 in->nDataChunks--;
4228                                 yaffs_DeleteChunk(dev, chunkId, 1, __LINE__);
4229                         }
4230                 }
4231         }
4232
4233 }
4234
4235 int yaffs_ResizeFile(yaffs_Object * in, loff_t newSize)
4236 {
4237
4238         int oldFileSize = in->variant.fileVariant.fileSize;
4239         int newSizeOfPartialChunk;
4240         int newFullChunks;
4241
4242         yaffs_Device *dev = in->myDev;
4243
4244         yaffs_AddrToChunk(dev, newSize, &newFullChunks, &newSizeOfPartialChunk);
4245
4246         yaffs_FlushFilesChunkCache(in);
4247         yaffs_InvalidateWholeChunkCache(in);
4248
4249         yaffs_CheckGarbageCollection(dev);
4250
4251         if (in->variantType != YAFFS_OBJECT_TYPE_FILE) {
4252                 return yaffs_GetFileSize(in);
4253         }
4254
4255         if (newSize == oldFileSize) {
4256                 return oldFileSize;
4257         }
4258
4259         if (newSize < oldFileSize) {
4260
4261                 yaffs_PruneResizedChunks(in, newSize);
4262
4263                 if (newSizeOfPartialChunk != 0) {
4264                         int lastChunk = 1 + newFullChunks;
4265
4266                         __u8 *localBuffer = yaffs_GetTempBuffer(dev, __LINE__);
4267
4268                         /* Got to read and rewrite the last chunk with its new size and zero pad */
4269                         yaffs_ReadChunkDataFromObject(in, lastChunk,
4270                                                       localBuffer);
4271
4272                         memset(localBuffer + newSizeOfPartialChunk, 0,
4273                                dev->nDataBytesPerChunk - newSizeOfPartialChunk);
4274
4275                         yaffs_WriteChunkDataToObject(in, lastChunk, localBuffer,
4276                                                      newSizeOfPartialChunk, 1);
4277
4278                         yaffs_ReleaseTempBuffer(dev, localBuffer, __LINE__);
4279                 }
4280
4281                 in->variant.fileVariant.fileSize = newSize;
4282
4283                 yaffs_PruneFileStructure(dev, &in->variant.fileVariant);
4284         }
4285         /* Write a new object header.
4286          * show we've shrunk the file, if need be
4287          * Do this only if the file is not in the deleted directories.
4288          */
4289         if (in->parent->objectId != YAFFS_OBJECTID_UNLINKED &&
4290             in->parent->objectId != YAFFS_OBJECTID_DELETED) {
4291                 yaffs_UpdateObjectHeader(in, NULL, 0,
4292                                          (newSize < oldFileSize) ? 1 : 0, 0);
4293         }
4294
4295         return newSize;
4296 }
4297
4298 loff_t yaffs_GetFileSize(yaffs_Object * obj)
4299 {
4300         obj = yaffs_GetEquivalentObject(obj);
4301
4302         switch (obj->variantType) {
4303         case YAFFS_OBJECT_TYPE_FILE:
4304                 return obj->variant.fileVariant.fileSize;
4305         case YAFFS_OBJECT_TYPE_SYMLINK:
4306                 return yaffs_strlen(obj->variant.symLinkVariant.alias);
4307         default:
4308                 return 0;
4309         }
4310 }
4311
4312
4313
4314 int yaffs_FlushFile(yaffs_Object * in, int updateTime)
4315 {
4316         int retVal;
4317         if (in->dirty) {
4318                 yaffs_FlushFilesChunkCache(in);
4319                 if (updateTime) {
4320 #ifdef CONFIG_YAFFS_WINCE
4321                         yfsd_WinFileTimeNow(in->win_mtime);
4322 #else
4323
4324                         in->yst_mtime = Y_CURRENT_TIME;
4325
4326 #endif
4327                 }
4328
4329                 retVal =
4330                     (yaffs_UpdateObjectHeader(in, NULL, 0, 0, 0) >=
4331                      0) ? YAFFS_OK : YAFFS_FAIL;
4332         } else {
4333                 retVal = YAFFS_OK;
4334         }
4335
4336         return retVal;
4337
4338 }
4339
4340 static int yaffs_DoGenericObjectDeletion(yaffs_Object * in)
4341 {
4342
4343         /* First off, invalidate the file's data in the cache, without flushing. */
4344         yaffs_InvalidateWholeChunkCache(in);
4345
4346         if (in->myDev->isYaffs2 && (in->parent != in->myDev->deletedDir)) {
4347                 /* Move to the unlinked directory so we have a record that it was deleted. */
4348                 yaffs_ChangeObjectName(in, in->myDev->deletedDir, NULL, 0, 0);
4349
4350         }
4351
4352         yaffs_RemoveObjectFromDirectory(in);
4353         yaffs_DeleteChunk(in->myDev, in->chunkId, 1, __LINE__);
4354         in->chunkId = -1;
4355
4356         yaffs_FreeObject(in);
4357         return YAFFS_OK;
4358
4359 }
4360
4361 /* yaffs_DeleteFile deletes the whole file data
4362  * and the inode associated with the file.
4363  * It does not delete the links associated with the file.
4364  */
4365 static int yaffs_UnlinkFile(yaffs_Object * in)
4366 {
4367
4368         int retVal;
4369         int immediateDeletion = 0;
4370
4371         if (1) {
4372 #ifdef __KERNEL__
4373                 if (!in->myInode) {
4374                         immediateDeletion = 1;
4375
4376                 }
4377 #else
4378                 if (in->inUse <= 0) {
4379                         immediateDeletion = 1;
4380
4381                 }
4382 #endif
4383                 if (immediateDeletion) {
4384                         retVal =
4385                             yaffs_ChangeObjectName(in, in->myDev->deletedDir,
4386                                                    NULL, 0, 0);
4387                         T(YAFFS_TRACE_TRACING,
4388                           (TSTR("yaffs: immediate deletion of file %d" TENDSTR),
4389                            in->objectId));
4390                         in->deleted = 1;
4391                         in->myDev->nDeletedFiles++;
4392                         if (0 && in->myDev->isYaffs2) {
4393                                 yaffs_ResizeFile(in, 0);
4394                         }
4395                         yaffs_SoftDeleteFile(in);
4396                 } else {
4397                         retVal =
4398                             yaffs_ChangeObjectName(in, in->myDev->unlinkedDir,
4399                                                    NULL, 0, 0);
4400                 }
4401
4402         }
4403         return retVal;
4404 }
4405
4406 int yaffs_DeleteFile(yaffs_Object * in)
4407 {
4408         int retVal = YAFFS_OK;
4409
4410         if (in->nDataChunks > 0) {
4411                 /* Use soft deletion if there is data in the file */
4412                 if (!in->unlinked) {
4413                         retVal = yaffs_UnlinkFile(in);
4414                 }
4415                 if (retVal == YAFFS_OK && in->unlinked && !in->deleted) {
4416                         in->deleted = 1;
4417                         in->myDev->nDeletedFiles++;
4418                         yaffs_SoftDeleteFile(in);
4419                 }
4420                 return in->deleted ? YAFFS_OK : YAFFS_FAIL;
4421         } else {
4422                 /* The file has no data chunks so we toss it immediately */
4423                 yaffs_FreeTnode(in->myDev, in->variant.fileVariant.top);
4424                 in->variant.fileVariant.top = NULL;
4425                 yaffs_DoGenericObjectDeletion(in);
4426
4427                 return YAFFS_OK;
4428         }
4429 }
4430
4431 static int yaffs_DeleteDirectory(yaffs_Object * in)
4432 {
4433         /* First check that the directory is empty. */
4434         if (list_empty(&in->variant.directoryVariant.children)) {
4435                 return yaffs_DoGenericObjectDeletion(in);
4436         }
4437
4438         return YAFFS_FAIL;
4439
4440 }
4441
4442 static int yaffs_DeleteSymLink(yaffs_Object * in)
4443 {
4444         YFREE(in->variant.symLinkVariant.alias);
4445
4446         return yaffs_DoGenericObjectDeletion(in);
4447 }
4448
4449 static int yaffs_DeleteHardLink(yaffs_Object * in)
4450 {
4451         /* remove this hardlink from the list assocaited with the equivalent
4452          * object
4453          */
4454         list_del(&in->hardLinks);
4455         return yaffs_DoGenericObjectDeletion(in);
4456 }
4457
4458 static void yaffs_DestroyObject(yaffs_Object * obj)
4459 {
4460         switch (obj->variantType) {
4461         case YAFFS_OBJECT_TYPE_FILE:
4462                 yaffs_DeleteFile(obj);
4463                 break;
4464         case YAFFS_OBJECT_TYPE_DIRECTORY:
4465                 yaffs_DeleteDirectory(obj);
4466                 break;
4467         case YAFFS_OBJECT_TYPE_SYMLINK:
4468                 yaffs_DeleteSymLink(obj);
4469                 break;
4470         case YAFFS_OBJECT_TYPE_HARDLINK:
4471                 yaffs_DeleteHardLink(obj);
4472                 break;
4473         case YAFFS_OBJECT_TYPE_SPECIAL:
4474                 yaffs_DoGenericObjectDeletion(obj);
4475                 break;
4476         case YAFFS_OBJECT_TYPE_UNKNOWN:
4477                 break;          /* should not happen. */
4478         }
4479 }
4480
4481 static int yaffs_UnlinkWorker(yaffs_Object * obj)
4482 {
4483
4484         if (obj->variantType == YAFFS_OBJECT_TYPE_HARDLINK) {
4485                 return yaffs_DeleteHardLink(obj);
4486         } else if (!list_empty(&obj->hardLinks)) {
4487                 /* Curve ball: We're unlinking an object that has a hardlink.
4488                  *
4489                  * This problem arises because we are not strictly following
4490                  * The Linux link/inode model.
4491                  *
4492                  * We can't really delete the object.
4493                  * Instead, we do the following:
4494                  * - Select a hardlink.
4495                  * - Unhook it from the hard links
4496                  * - Unhook it from its parent directory (so that the rename can work)
4497                  * - Rename the object to the hardlink's name.
4498                  * - Delete the hardlink
4499                  */
4500
4501                 yaffs_Object *hl;
4502                 int retVal;
4503                 YCHAR name[YAFFS_MAX_NAME_LENGTH + 1];
4504
4505                 hl = list_entry(obj->hardLinks.next, yaffs_Object, hardLinks);
4506
4507                 list_del_init(&hl->hardLinks);
4508                 list_del_init(&hl->siblings);
4509
4510                 yaffs_GetObjectName(hl, name, YAFFS_MAX_NAME_LENGTH + 1);
4511
4512                 retVal = yaffs_ChangeObjectName(obj, hl->parent, name, 0, 0);
4513
4514                 if (retVal == YAFFS_OK) {
4515                         retVal = yaffs_DoGenericObjectDeletion(hl);
4516                 }
4517                 return retVal;
4518
4519         } else {
4520                 switch (obj->variantType) {
4521                 case YAFFS_OBJECT_TYPE_FILE:
4522                         return yaffs_UnlinkFile(obj);
4523                         break;
4524                 case YAFFS_OBJECT_TYPE_DIRECTORY:
4525                         return yaffs_DeleteDirectory(obj);
4526                         break;
4527                 case YAFFS_OBJECT_TYPE_SYMLINK:
4528                         return yaffs_DeleteSymLink(obj);
4529                         break;
4530                 case YAFFS_OBJECT_TYPE_SPECIAL:
4531                         return yaffs_DoGenericObjectDeletion(obj);
4532                         break;
4533                 case YAFFS_OBJECT_TYPE_HARDLINK:
4534                 case YAFFS_OBJECT_TYPE_UNKNOWN:
4535                 default:
4536                         return YAFFS_FAIL;
4537                 }
4538         }
4539 }
4540
4541
4542 static int yaffs_UnlinkObject( yaffs_Object *obj)
4543 {
4544
4545         if (obj && obj->unlinkAllowed) {
4546                 return yaffs_UnlinkWorker(obj);
4547         }
4548
4549         return YAFFS_FAIL;
4550
4551 }
4552 int yaffs_Unlink(yaffs_Object * dir, const YCHAR * name)
4553 {
4554         yaffs_Object *obj;
4555
4556         obj = yaffs_FindObjectByName(dir, name);
4557         return yaffs_UnlinkObject(obj);
4558 }
4559
4560 /*----------------------- Initialisation Scanning ---------------------- */
4561
4562 static void yaffs_HandleShadowedObject(yaffs_Device * dev, int objId,
4563                                        int backwardScanning)
4564 {
4565         yaffs_Object *obj;
4566
4567         if (!backwardScanning) {
4568                 /* Handle YAFFS1 forward scanning case
4569                  * For YAFFS1 we always do the deletion
4570                  */
4571
4572         } else {
4573                 /* Handle YAFFS2 case (backward scanning)
4574                  * If the shadowed object exists then ignore.
4575                  */
4576                 if (yaffs_FindObjectByNumber(dev, objId)) {
4577                         return;
4578                 }
4579         }
4580
4581         /* Let's create it (if it does not exist) assuming it is a file so that it can do shrinking etc.
4582          * We put it in unlinked dir to be cleaned up after the scanning
4583          */
4584         obj =
4585             yaffs_FindOrCreateObjectByNumber(dev, objId,
4586                                              YAFFS_OBJECT_TYPE_FILE);
4587         yaffs_AddObjectToDirectory(dev->unlinkedDir, obj);
4588         obj->variant.fileVariant.shrinkSize = 0;
4589         obj->valid = 1;         /* So that we don't read any other info for this file */
4590
4591 }
4592
4593 typedef struct {
4594         int seq;
4595         int block;
4596 } yaffs_BlockIndex;
4597
4598
4599 static void yaffs_HardlinkFixup(yaffs_Device *dev, yaffs_Object *hardList)
4600 {
4601         yaffs_Object *hl;
4602         yaffs_Object *in;
4603
4604         while (hardList) {
4605                 hl = hardList;
4606                 hardList = (yaffs_Object *) (hardList->hardLinks.next);
4607
4608                 in = yaffs_FindObjectByNumber(dev,
4609                                               hl->variant.hardLinkVariant.
4610                                               equivalentObjectId);
4611
4612                 if (in) {
4613                         /* Add the hardlink pointers */
4614                         hl->variant.hardLinkVariant.equivalentObject = in;
4615                         list_add(&hl->hardLinks, &in->hardLinks);
4616                 } else {
4617                         /* Todo Need to report/handle this better.
4618                          * Got a problem... hardlink to a non-existant object
4619                          */
4620                         hl->variant.hardLinkVariant.equivalentObject = NULL;
4621                         INIT_LIST_HEAD(&hl->hardLinks);
4622
4623                 }
4624
4625         }
4626
4627 }
4628
4629
4630
4631
4632
4633 static int ybicmp(const void *a, const void *b){
4634     register int aseq = ((yaffs_BlockIndex *)a)->seq;
4635     register int bseq = ((yaffs_BlockIndex *)b)->seq;
4636     register int ablock = ((yaffs_BlockIndex *)a)->block;
4637     register int bblock = ((yaffs_BlockIndex *)b)->block;
4638     if( aseq == bseq )
4639         return ablock - bblock;
4640     else
4641         return aseq - bseq;
4642
4643 }
4644
4645 static int yaffs_Scan(yaffs_Device * dev)
4646 {
4647         yaffs_ExtendedTags tags;
4648         int blk;
4649         int blockIterator;
4650         int startIterator;
4651         int endIterator;
4652         int nBlocksToScan = 0;
4653         int result;
4654
4655         int chunk;
4656         int c;
4657         int deleted;
4658         yaffs_BlockState state;
4659         yaffs_Object *hardList = NULL;
4660         yaffs_Object *hl;
4661         yaffs_BlockInfo *bi;
4662         int sequenceNumber;
4663         yaffs_ObjectHeader *oh;
4664         yaffs_Object *in;
4665         yaffs_Object *parent;
4666         int nBlocks = dev->internalEndBlock - dev->internalStartBlock + 1;
4667
4668         __u8 *chunkData;
4669
4670         yaffs_BlockIndex *blockIndex = NULL;
4671
4672         if (dev->isYaffs2) {
4673                 T(YAFFS_TRACE_SCAN,
4674                   (TSTR("yaffs_Scan is not for YAFFS2!" TENDSTR)));
4675                 return YAFFS_FAIL;
4676         }
4677
4678         //TODO  Throw all the yaffs2 stuuf out of yaffs_Scan since it is only for yaffs1 format.
4679
4680         T(YAFFS_TRACE_SCAN,
4681           (TSTR("yaffs_Scan starts  intstartblk %d intendblk %d..." TENDSTR),
4682            dev->internalStartBlock, dev->internalEndBlock));
4683
4684         chunkData = yaffs_GetTempBuffer(dev, __LINE__);
4685
4686         dev->sequenceNumber = YAFFS_LOWEST_SEQUENCE_NUMBER;
4687
4688         if (dev->isYaffs2) {
4689                 blockIndex = YMALLOC(nBlocks * sizeof(yaffs_BlockIndex));
4690         }
4691
4692         /* Scan all the blocks to determine their state */
4693         for (blk = dev->internalStartBlock; blk <= dev->internalEndBlock; blk++) {
4694                 bi = yaffs_GetBlockInfo(dev, blk);
4695                 yaffs_ClearChunkBits(dev, blk);
4696                 bi->pagesInUse = 0;
4697                 bi->softDeletions = 0;
4698
4699                 yaffs_QueryInitialBlockState(dev, blk, &state, &sequenceNumber);
4700
4701                 bi->blockState = state;
4702                 bi->sequenceNumber = sequenceNumber;
4703
4704                 T(YAFFS_TRACE_SCAN_DEBUG,
4705                   (TSTR("Block scanning block %d state %d seq %d" TENDSTR), blk,
4706                    state, sequenceNumber));
4707
4708                 if (state == YAFFS_BLOCK_STATE_DEAD) {
4709                         T(YAFFS_TRACE_BAD_BLOCKS,
4710                           (TSTR("block %d is bad" TENDSTR), blk));
4711                 } else if (state == YAFFS_BLOCK_STATE_EMPTY) {
4712                         T(YAFFS_TRACE_SCAN_DEBUG,
4713                           (TSTR("Block empty " TENDSTR)));
4714                         dev->nErasedBlocks++;
4715                         dev->nFreeChunks += dev->nChunksPerBlock;
4716                 } else if (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING) {
4717
4718                         /* Determine the highest sequence number */
4719                         if (dev->isYaffs2 &&
4720                             sequenceNumber >= YAFFS_LOWEST_SEQUENCE_NUMBER &&
4721                             sequenceNumber < YAFFS_HIGHEST_SEQUENCE_NUMBER) {
4722
4723                                 blockIndex[nBlocksToScan].seq = sequenceNumber;
4724                                 blockIndex[nBlocksToScan].block = blk;
4725
4726                                 nBlocksToScan++;
4727
4728                                 if (sequenceNumber >= dev->sequenceNumber) {
4729                                         dev->sequenceNumber = sequenceNumber;
4730                                 }
4731                         } else if (dev->isYaffs2) {
4732                                 /* TODO: Nasty sequence number! */
4733                                 T(YAFFS_TRACE_SCAN,
4734                                   (TSTR
4735                                    ("Block scanning block %d has bad sequence number %d"
4736                                     TENDSTR), blk, sequenceNumber));
4737
4738                         }
4739                 }
4740         }
4741
4742         /* Sort the blocks
4743          * Dungy old bubble sort for now...
4744          */
4745         if (dev->isYaffs2) {
4746                 yaffs_BlockIndex temp;
4747                 int i;
4748                 int j;
4749
4750                 for (i = 0; i < nBlocksToScan; i++)
4751                         for (j = i + 1; j < nBlocksToScan; j++)
4752                                 if (blockIndex[i].seq > blockIndex[j].seq) {
4753                                         temp = blockIndex[j];
4754                                         blockIndex[j] = blockIndex[i];
4755                                         blockIndex[i] = temp;
4756                                 }
4757         }
4758
4759         /* Now scan the blocks looking at the data. */
4760         if (dev->isYaffs2) {
4761                 startIterator = 0;
4762                 endIterator = nBlocksToScan - 1;
4763                 T(YAFFS_TRACE_SCAN_DEBUG,
4764                   (TSTR("%d blocks to be scanned" TENDSTR), nBlocksToScan));
4765         } else {
4766                 startIterator = dev->internalStartBlock;
4767                 endIterator = dev->internalEndBlock;
4768         }
4769
4770         /* For each block.... */
4771         for (blockIterator = startIterator; blockIterator <= endIterator;
4772              blockIterator++) {
4773
4774                 if (dev->isYaffs2) {
4775                         /* get the block to scan in the correct order */
4776                         blk = blockIndex[blockIterator].block;
4777                 } else {
4778                         blk = blockIterator;
4779                 }
4780
4781                 bi = yaffs_GetBlockInfo(dev, blk);
4782                 state = bi->blockState;
4783
4784                 deleted = 0;
4785
4786                 /* For each chunk in each block that needs scanning....*/
4787                 for (c = 0; c < dev->nChunksPerBlock &&
4788                      state == YAFFS_BLOCK_STATE_NEEDS_SCANNING; c++) {
4789                         /* Read the tags and decide what to do */
4790                         chunk = blk * dev->nChunksPerBlock + c;
4791
4792                         result = yaffs_ReadChunkWithTagsFromNAND(dev, chunk, NULL,
4793                                                         &tags);
4794
4795                         /* Let's have a good look at this chunk... */
4796
4797                         if (!dev->isYaffs2 && tags.chunkDeleted) {
4798                                 /* YAFFS1 only...
4799                                  * A deleted chunk
4800                                  */
4801                                 deleted++;
4802                                 dev->nFreeChunks++;
4803                                 /*T((" %d %d deleted\n",blk,c)); */
4804                         } else if (!tags.chunkUsed) {
4805                                 /* An unassigned chunk in the block
4806                                  * This means that either the block is empty or
4807                                  * this is the one being allocated from
4808                                  */
4809
4810                                 if (c == 0) {
4811                                         /* We're looking at the first chunk in the block so the block is unused */
4812                                         state = YAFFS_BLOCK_STATE_EMPTY;
4813                                         dev->nErasedBlocks++;
4814                                 } else {
4815                                         /* this is the block being allocated from */
4816                                         T(YAFFS_TRACE_SCAN,
4817                                           (TSTR
4818                                            (" Allocating from %d %d" TENDSTR),
4819                                            blk, c));
4820                                         state = YAFFS_BLOCK_STATE_ALLOCATING;
4821                                         dev->allocationBlock = blk;
4822                                         dev->allocationPage = c;
4823                                         dev->allocationBlockFinder = blk;
4824                                         /* Set it to here to encourage the allocator to go forth from here. */
4825
4826                                         /* Yaffs2 sanity check:
4827                                          * This should be the one with the highest sequence number
4828                                          */
4829                                         if (dev->isYaffs2
4830                                             && (dev->sequenceNumber !=
4831                                                 bi->sequenceNumber)) {
4832                                                 T(YAFFS_TRACE_ALWAYS,
4833                                                   (TSTR
4834                                                    ("yaffs: Allocation block %d was not highest sequence id:"
4835                                                     " block seq = %d, dev seq = %d"
4836                                                     TENDSTR), blk,bi->sequenceNumber,dev->sequenceNumber));
4837                                         }
4838                                 }
4839
4840                                 dev->nFreeChunks += (dev->nChunksPerBlock - c);
4841                         } else if (tags.chunkId > 0) {
4842                                 /* chunkId > 0 so it is a data chunk... */
4843                                 unsigned int endpos;
4844
4845                                 yaffs_SetChunkBit(dev, blk, c);
4846                                 bi->pagesInUse++;
4847
4848                                 in = yaffs_FindOrCreateObjectByNumber(dev,
4849                                                                       tags.
4850                                                                       objectId,
4851                                                                       YAFFS_OBJECT_TYPE_FILE);
4852                                 /* PutChunkIntoFile checks for a clash (two data chunks with
4853                                  * the same chunkId).
4854                                  */
4855                                 yaffs_PutChunkIntoFile(in, tags.chunkId, chunk,
4856                                                        1);
4857                                 endpos =
4858                                     (tags.chunkId - 1) * dev->nDataBytesPerChunk +
4859                                     tags.byteCount;
4860                                 if (in->variantType == YAFFS_OBJECT_TYPE_FILE
4861                                     && in->variant.fileVariant.scannedFileSize <
4862                                     endpos) {
4863                                         in->variant.fileVariant.
4864                                             scannedFileSize = endpos;
4865                                         if (!dev->useHeaderFileSize) {
4866                                                 in->variant.fileVariant.
4867                                                     fileSize =
4868                                                     in->variant.fileVariant.
4869                                                     scannedFileSize;
4870                                         }
4871
4872                                 }
4873                                 /* T((" %d %d data %d %d\n",blk,c,tags.objectId,tags.chunkId));   */
4874                         } else {
4875                                 /* chunkId == 0, so it is an ObjectHeader.
4876                                  * Thus, we read in the object header and make the object
4877                                  */
4878                                 yaffs_SetChunkBit(dev, blk, c);
4879                                 bi->pagesInUse++;
4880
4881                                 result = yaffs_ReadChunkWithTagsFromNAND(dev, chunk,
4882                                                                 chunkData,
4883                                                                 NULL);
4884
4885                                 oh = (yaffs_ObjectHeader *) chunkData;
4886
4887                                 in = yaffs_FindObjectByNumber(dev,
4888                                                               tags.objectId);
4889                                 if (in && in->variantType != oh->type) {
4890                                         /* This should not happen, but somehow
4891                                          * Wev'e ended up with an objectId that has been reused but not yet
4892                                          * deleted, and worse still it has changed type. Delete the old object.
4893                                          */
4894
4895                                         yaffs_DestroyObject(in);
4896
4897                                         in = 0;
4898                                 }
4899
4900                                 in = yaffs_FindOrCreateObjectByNumber(dev,
4901                                                                       tags.
4902                                                                       objectId,
4903                                                                       oh->type);
4904
4905                                 if (oh->shadowsObject > 0) {
4906                                         yaffs_HandleShadowedObject(dev,
4907                                                                    oh->
4908                                                                    shadowsObject,
4909                                                                    0);
4910                                 }
4911
4912                                 if (in->valid) {
4913                                         /* We have already filled this one. We have a duplicate and need to resolve it. */
4914
4915                                         unsigned existingSerial = in->serial;
4916                                         unsigned newSerial = tags.serialNumber;
4917
4918                                         if (dev->isYaffs2 ||
4919                                             ((existingSerial + 1) & 3) ==
4920                                             newSerial) {
4921                                                 /* Use new one - destroy the exisiting one */
4922                                                 yaffs_DeleteChunk(dev,
4923                                                                   in->chunkId,
4924                                                                   1, __LINE__);
4925                                                 in->valid = 0;
4926                                         } else {
4927                                                 /* Use existing - destroy this one. */
4928                                                 yaffs_DeleteChunk(dev, chunk, 1,
4929                                                                   __LINE__);
4930                                         }
4931                                 }
4932
4933                                 if (!in->valid &&
4934                                     (tags.objectId == YAFFS_OBJECTID_ROOT ||
4935                                      tags.objectId == YAFFS_OBJECTID_LOSTNFOUND)) {
4936                                         /* We only load some info, don't fiddle with directory structure */
4937                                         in->valid = 1;
4938                                         in->variantType = oh->type;
4939
4940                                         in->yst_mode = oh->yst_mode;
4941 #ifdef CONFIG_YAFFS_WINCE
4942                                         in->win_atime[0] = oh->win_atime[0];
4943                                         in->win_ctime[0] = oh->win_ctime[0];
4944                                         in->win_mtime[0] = oh->win_mtime[0];
4945                                         in->win_atime[1] = oh->win_atime[1];
4946                                         in->win_ctime[1] = oh->win_ctime[1];
4947                                         in->win_mtime[1] = oh->win_mtime[1];
4948 #else
4949                                         in->yst_uid = oh->yst_uid;
4950                                         in->yst_gid = oh->yst_gid;
4951                                         in->yst_atime = oh->yst_atime;
4952                                         in->yst_mtime = oh->yst_mtime;
4953                                         in->yst_ctime = oh->yst_ctime;
4954                                         in->yst_rdev = oh->yst_rdev;
4955 #endif
4956                                         in->chunkId = chunk;
4957
4958                                 } else if (!in->valid) {
4959                                         /* we need to load this info */
4960
4961                                         in->valid = 1;
4962                                         in->variantType = oh->type;
4963
4964                                         in->yst_mode = oh->yst_mode;
4965 #ifdef CONFIG_YAFFS_WINCE
4966                                         in->win_atime[0] = oh->win_atime[0];
4967                                         in->win_ctime[0] = oh->win_ctime[0];
4968                                         in->win_mtime[0] = oh->win_mtime[0];
4969                                         in->win_atime[1] = oh->win_atime[1];
4970                                         in->win_ctime[1] = oh->win_ctime[1];
4971                                         in->win_mtime[1] = oh->win_mtime[1];
4972 #else
4973                                         in->yst_uid = oh->yst_uid;
4974                                         in->yst_gid = oh->yst_gid;
4975                                         in->yst_atime = oh->yst_atime;
4976                                         in->yst_mtime = oh->yst_mtime;
4977                                         in->yst_ctime = oh->yst_ctime;
4978                                         in->yst_rdev = oh->yst_rdev;
4979 #endif
4980                                         in->chunkId = chunk;
4981
4982                                         yaffs_SetObjectName(in, oh->name);
4983                                         in->dirty = 0;
4984
4985                                         /* directory stuff...
4986                                          * hook up to parent
4987                                          */
4988
4989                                         parent =
4990                                             yaffs_FindOrCreateObjectByNumber
4991                                             (dev, oh->parentObjectId,
4992                                              YAFFS_OBJECT_TYPE_DIRECTORY);
4993                                         if (parent->variantType ==
4994                                             YAFFS_OBJECT_TYPE_UNKNOWN) {
4995                                                 /* Set up as a directory */
4996                                                 parent->variantType =
4997                                                     YAFFS_OBJECT_TYPE_DIRECTORY;
4998                                                 INIT_LIST_HEAD(&parent->variant.
4999                                                                directoryVariant.
5000                                                                children);
5001                                         } else if (parent->variantType !=
5002                                                    YAFFS_OBJECT_TYPE_DIRECTORY)
5003                                         {
5004                                                 /* Hoosterman, another problem....
5005                                                  * We're trying to use a non-directory as a directory
5006                                                  */
5007
5008                                                 T(YAFFS_TRACE_ERROR,
5009                                                   (TSTR
5010                                                    ("yaffs tragedy: attempting to use non-directory as"
5011                                                     " a directory in scan. Put in lost+found."
5012                                                     TENDSTR)));
5013                                                 parent = dev->lostNFoundDir;
5014                                         }
5015
5016                                         yaffs_AddObjectToDirectory(parent, in);
5017
5018                                         if (0 && (parent == dev->deletedDir ||
5019                                                   parent == dev->unlinkedDir)) {
5020                                                 in->deleted = 1;        /* If it is unlinked at start up then it wants deleting */
5021                                                 dev->nDeletedFiles++;
5022                                         }
5023                                         /* Note re hardlinks.
5024                                          * Since we might scan a hardlink before its equivalent object is scanned
5025                                          * we put them all in a list.
5026                                          * After scanning is complete, we should have all the objects, so we run through this
5027                                          * list and fix up all the chains.
5028                                          */
5029
5030                                         switch (in->variantType) {
5031                                         case YAFFS_OBJECT_TYPE_UNKNOWN:
5032                                                 /* Todo got a problem */
5033                                                 break;
5034                                         case YAFFS_OBJECT_TYPE_FILE:
5035                                                 if (dev->isYaffs2
5036                                                     && oh->isShrink) {
5037                                                         /* Prune back the shrunken chunks */
5038                                                         yaffs_PruneResizedChunks
5039                                                             (in, oh->fileSize);
5040                                                         /* Mark the block as having a shrinkHeader */
5041                                                         bi->hasShrinkHeader = 1;
5042                                                 }
5043
5044                                                 if (dev->useHeaderFileSize)
5045
5046                                                         in->variant.fileVariant.
5047                                                             fileSize =
5048                                                             oh->fileSize;
5049
5050                                                 break;
5051                                         case YAFFS_OBJECT_TYPE_HARDLINK:
5052                                                 in->variant.hardLinkVariant.
5053                                                     equivalentObjectId =
5054                                                     oh->equivalentObjectId;
5055                                                 in->hardLinks.next =
5056                                                     (struct list_head *)
5057                                                     hardList;
5058                                                 hardList = in;
5059                                                 break;
5060                                         case YAFFS_OBJECT_TYPE_DIRECTORY:
5061                                                 /* Do nothing */
5062                                                 break;
5063                                         case YAFFS_OBJECT_TYPE_SPECIAL:
5064                                                 /* Do nothing */
5065                                                 break;
5066                                         case YAFFS_OBJECT_TYPE_SYMLINK:
5067                                                 in->variant.symLinkVariant.
5068                                                     alias =
5069                                                     yaffs_CloneString(oh->alias);
5070                                                 break;
5071                                         }
5072
5073                                         if (parent == dev->deletedDir) {
5074                                                 yaffs_DestroyObject(in);
5075                                                 bi->hasShrinkHeader = 1;
5076                                         }
5077                                 }
5078                         }
5079                 }
5080
5081                 if (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING) {
5082                         /* If we got this far while scanning, then the block is fully allocated.*/
5083                         state = YAFFS_BLOCK_STATE_FULL;
5084                 }
5085
5086                 bi->blockState = state;
5087
5088                 /* Now let's see if it was dirty */
5089                 if (bi->pagesInUse == 0 &&
5090                     !bi->hasShrinkHeader &&
5091                     bi->blockState == YAFFS_BLOCK_STATE_FULL) {
5092                         yaffs_BlockBecameDirty(dev, blk);
5093                 }
5094
5095         }
5096
5097         if (blockIndex) {
5098                 YFREE(blockIndex);
5099         }
5100
5101
5102         /* Ok, we've done all the scanning.
5103          * Fix up the hard link chains.
5104          * We should now have scanned all the objects, now it's time to add these
5105          * hardlinks.
5106          */
5107
5108         yaffs_HardlinkFixup(dev,hardList);
5109
5110         /* Handle the unlinked files. Since they were left in an unlinked state we should
5111          * just delete them.
5112          */
5113         {
5114                 struct list_head *i;
5115                 struct list_head *n;
5116
5117                 yaffs_Object *l;
5118                 /* Soft delete all the unlinked files */
5119                 list_for_each_safe(i, n,
5120                                    &dev->unlinkedDir->variant.directoryVariant.
5121                                    children) {
5122                         if (i) {
5123                                 l = list_entry(i, yaffs_Object, siblings);
5124                                 yaffs_DestroyObject(l);
5125                         }
5126                 }
5127         }
5128
5129         yaffs_ReleaseTempBuffer(dev, chunkData, __LINE__);
5130
5131         T(YAFFS_TRACE_SCAN, (TSTR("yaffs_Scan ends" TENDSTR)));
5132
5133         return YAFFS_OK;
5134 }
5135
5136 static void yaffs_CheckObjectDetailsLoaded(yaffs_Object *in)
5137 {
5138         __u8 *chunkData;
5139         yaffs_ObjectHeader *oh;
5140         yaffs_Device *dev = in->myDev;
5141         yaffs_ExtendedTags tags;
5142         int result;
5143
5144         if(in->lazyLoaded){
5145                 in->lazyLoaded = 0;
5146                 chunkData = yaffs_GetTempBuffer(dev, __LINE__);
5147
5148                 result = yaffs_ReadChunkWithTagsFromNAND(dev,in->chunkId,chunkData,&tags);
5149                 oh = (yaffs_ObjectHeader *) chunkData;
5150
5151                 in->yst_mode = oh->yst_mode;
5152 #ifdef CONFIG_YAFFS_WINCE
5153                 in->win_atime[0] = oh->win_atime[0];
5154                 in->win_ctime[0] = oh->win_ctime[0];
5155                 in->win_mtime[0] = oh->win_mtime[0];
5156                 in->win_atime[1] = oh->win_atime[1];
5157                 in->win_ctime[1] = oh->win_ctime[1];
5158                 in->win_mtime[1] = oh->win_mtime[1];
5159 #else
5160                 in->yst_uid = oh->yst_uid;
5161                 in->yst_gid = oh->yst_gid;
5162                 in->yst_atime = oh->yst_atime;
5163                 in->yst_mtime = oh->yst_mtime;
5164                 in->yst_ctime = oh->yst_ctime;
5165                 in->yst_rdev = oh->yst_rdev;
5166
5167 #endif
5168                 yaffs_SetObjectName(in, oh->name);
5169
5170                 if(in->variantType == YAFFS_OBJECT_TYPE_SYMLINK)
5171                          in->variant.symLinkVariant.alias =
5172                                                     yaffs_CloneString(oh->alias);
5173
5174                 yaffs_ReleaseTempBuffer(dev,chunkData, __LINE__);
5175         }
5176 }
5177
5178 static int yaffs_ScanBackwards(yaffs_Device * dev)
5179 {
5180         yaffs_ExtendedTags tags;
5181         int blk;
5182         int blockIterator;
5183         int startIterator;
5184         int endIterator;
5185         int nBlocksToScan = 0;
5186
5187         int chunk;
5188         int result;
5189         int c;
5190         int deleted;
5191         yaffs_BlockState state;
5192         yaffs_Object *hardList = NULL;
5193         yaffs_BlockInfo *bi;
5194         int sequenceNumber;
5195         yaffs_ObjectHeader *oh;
5196         yaffs_Object *in;
5197         yaffs_Object *parent;
5198         int nBlocks = dev->internalEndBlock - dev->internalStartBlock + 1;
5199         int itsUnlinked;
5200         __u8 *chunkData;
5201
5202         int fileSize;
5203         int isShrink;
5204         int foundChunksInBlock;
5205         int equivalentObjectId;
5206
5207
5208         yaffs_BlockIndex *blockIndex = NULL;
5209         int altBlockIndex = 0;
5210
5211         if (!dev->isYaffs2) {
5212                 T(YAFFS_TRACE_SCAN,
5213                   (TSTR("yaffs_ScanBackwards is only for YAFFS2!" TENDSTR)));
5214                 return YAFFS_FAIL;
5215         }
5216
5217         T(YAFFS_TRACE_SCAN,
5218           (TSTR
5219            ("yaffs_ScanBackwards starts  intstartblk %d intendblk %d..."
5220             TENDSTR), dev->internalStartBlock, dev->internalEndBlock));
5221
5222
5223         dev->sequenceNumber = YAFFS_LOWEST_SEQUENCE_NUMBER;
5224
5225         blockIndex = YMALLOC(nBlocks * sizeof(yaffs_BlockIndex));
5226
5227         if(!blockIndex) {
5228                 blockIndex = YMALLOC_ALT(nBlocks * sizeof(yaffs_BlockIndex));
5229                 altBlockIndex = 1;
5230         }
5231
5232         if(!blockIndex) {
5233                 T(YAFFS_TRACE_SCAN,
5234                   (TSTR("yaffs_Scan() could not allocate block index!" TENDSTR)));
5235                 return YAFFS_FAIL;
5236         }
5237
5238         chunkData = yaffs_GetTempBuffer(dev, __LINE__);
5239
5240         /* Scan all the blocks to determine their state */
5241         for (blk = dev->internalStartBlock; blk <= dev->internalEndBlock; blk++) {
5242                 bi = yaffs_GetBlockInfo(dev, blk);
5243                 yaffs_ClearChunkBits(dev, blk);
5244                 bi->pagesInUse = 0;
5245                 bi->softDeletions = 0;
5246
5247                 yaffs_QueryInitialBlockState(dev, blk, &state, &sequenceNumber);
5248
5249                 bi->blockState = state;
5250                 bi->sequenceNumber = sequenceNumber;
5251
5252                 if(bi->sequenceNumber == YAFFS_SEQUENCE_CHECKPOINT_DATA)
5253                         bi->blockState = state = YAFFS_BLOCK_STATE_CHECKPOINT;
5254
5255                 T(YAFFS_TRACE_SCAN_DEBUG,
5256                   (TSTR("Block scanning block %d state %d seq %d" TENDSTR), blk,
5257                    state, sequenceNumber));
5258
5259
5260                 if(state == YAFFS_BLOCK_STATE_CHECKPOINT){
5261                         /* todo .. fix free space ? */
5262
5263                 } else if (state == YAFFS_BLOCK_STATE_DEAD) {
5264                         T(YAFFS_TRACE_BAD_BLOCKS,
5265                           (TSTR("block %d is bad" TENDSTR), blk));
5266                 } else if (state == YAFFS_BLOCK_STATE_EMPTY) {
5267                         T(YAFFS_TRACE_SCAN_DEBUG,
5268                           (TSTR("Block empty " TENDSTR)));
5269                         dev->nErasedBlocks++;
5270                         dev->nFreeChunks += dev->nChunksPerBlock;
5271                 } else if (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING) {
5272
5273                         /* Determine the highest sequence number */
5274                         if (dev->isYaffs2 &&
5275                             sequenceNumber >= YAFFS_LOWEST_SEQUENCE_NUMBER &&
5276                             sequenceNumber < YAFFS_HIGHEST_SEQUENCE_NUMBER) {
5277
5278                                 blockIndex[nBlocksToScan].seq = sequenceNumber;
5279                                 blockIndex[nBlocksToScan].block = blk;
5280
5281                                 nBlocksToScan++;
5282
5283                                 if (sequenceNumber >= dev->sequenceNumber) {
5284                                         dev->sequenceNumber = sequenceNumber;
5285                                 }
5286                         } else if (dev->isYaffs2) {
5287                                 /* TODO: Nasty sequence number! */
5288                                 T(YAFFS_TRACE_SCAN,
5289                                   (TSTR
5290                                    ("Block scanning block %d has bad sequence number %d"
5291                                     TENDSTR), blk, sequenceNumber));
5292
5293                         }
5294                 }
5295         }
5296
5297         T(YAFFS_TRACE_SCAN,
5298         (TSTR("%d blocks to be sorted..." TENDSTR), nBlocksToScan));
5299
5300
5301
5302         YYIELD();
5303
5304         /* Sort the blocks */
5305 #ifndef CONFIG_YAFFS_USE_OWN_SORT
5306         {
5307                 /* Use qsort now. */
5308                 qsort(blockIndex, nBlocksToScan, sizeof(yaffs_BlockIndex), ybicmp);
5309         }
5310 #else
5311         {
5312                 /* Dungy old bubble sort... */
5313
5314                 yaffs_BlockIndex temp;
5315                 int i;
5316                 int j;
5317
5318                 for (i = 0; i < nBlocksToScan; i++)
5319                         for (j = i + 1; j < nBlocksToScan; j++)
5320                                 if (blockIndex[i].seq > blockIndex[j].seq) {
5321                                         temp = blockIndex[j];
5322                                         blockIndex[j] = blockIndex[i];
5323                                         blockIndex[i] = temp;
5324                                 }
5325         }
5326 #endif
5327
5328         YYIELD();
5329
5330         T(YAFFS_TRACE_SCAN, (TSTR("...done" TENDSTR)));
5331
5332         /* Now scan the blocks looking at the data. */
5333         startIterator = 0;
5334         endIterator = nBlocksToScan - 1;
5335         T(YAFFS_TRACE_SCAN_DEBUG,
5336           (TSTR("%d blocks to be scanned" TENDSTR), nBlocksToScan));
5337
5338         /* For each block.... backwards */
5339         for (blockIterator = endIterator; blockIterator >= startIterator;
5340              blockIterator--) {
5341                 /* Cooperative multitasking! This loop can run for so
5342                    long that watchdog timers expire. */
5343                 YYIELD();
5344
5345                 /* get the block to scan in the correct order */
5346                 blk = blockIndex[blockIterator].block;
5347
5348                 bi = yaffs_GetBlockInfo(dev, blk);
5349                 state = bi->blockState;
5350
5351                 deleted = 0;
5352
5353                 /* For each chunk in each block that needs scanning.... */
5354                 foundChunksInBlock = 0;
5355                 for (c = dev->nChunksPerBlock - 1; c >= 0 &&
5356                      (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING ||
5357                       state == YAFFS_BLOCK_STATE_ALLOCATING); c--) {
5358                         /* Scan backwards...
5359                          * Read the tags and decide what to do
5360                          */
5361                         chunk = blk * dev->nChunksPerBlock + c;
5362
5363                         result = yaffs_ReadChunkWithTagsFromNAND(dev, chunk, NULL,
5364                                                         &tags);
5365
5366                         /* Let's have a good look at this chunk... */
5367
5368                         if (!tags.chunkUsed) {
5369                                 /* An unassigned chunk in the block.
5370                                  * If there are used chunks after this one, then
5371                                  * it is a chunk that was skipped due to failing the erased
5372                                  * check. Just skip it so that it can be deleted.
5373                                  * But, more typically, We get here when this is an unallocated
5374                                  * chunk and his means that either the block is empty or
5375                                  * this is the one being allocated from
5376                                  */
5377
5378                                 if(foundChunksInBlock)
5379                                 {
5380                                         /* This is a chunk that was skipped due to failing the erased check */
5381
5382                                 } else if (c == 0) {
5383                                         /* We're looking at the first chunk in the block so the block is unused */
5384                                         state = YAFFS_BLOCK_STATE_EMPTY;
5385                                         dev->nErasedBlocks++;
5386                                 } else {
5387                                         /* this is the block being allocated from */
5388                                         if (state ==
5389                                             YAFFS_BLOCK_STATE_NEEDS_SCANNING) {
5390                                                 T(YAFFS_TRACE_SCAN,
5391                                                   (TSTR
5392                                                    (" Allocating from %d %d"
5393                                                     TENDSTR), blk, c));
5394                                         }
5395                                         state = YAFFS_BLOCK_STATE_ALLOCATING;
5396                                         dev->allocationBlock = blk;
5397                                         dev->allocationPage = c;
5398                                         dev->allocationBlockFinder = blk;
5399                                         /* Set it to here to encourage the allocator to
5400                                          *  go forth from here.
5401                                          */
5402
5403                                         /* Yaffs2 sanity check:
5404                                          * This should be the one with the highest sequence number
5405                                          */
5406                                         if (dev->isYaffs2
5407                                             && (dev->sequenceNumber !=
5408                                                 bi->sequenceNumber)) {
5409                                                 T(YAFFS_TRACE_ALWAYS,
5410                                                   (TSTR
5411                                                    ("yaffs: Allocation block %d was not highest sequence "
5412                                                     "id: block seq = %d, dev seq = %d"
5413                                                     TENDSTR), blk,
5414                                                    bi->sequenceNumber,
5415                                                    dev->sequenceNumber));
5416                                         }
5417                                 }
5418
5419                                 dev->nFreeChunks++;
5420                         } else if (tags.chunkId > 0) {
5421                                 /* chunkId > 0 so it is a data chunk... */
5422                                 unsigned int endpos;
5423                                 __u32 chunkBase =
5424                                     (tags.chunkId - 1) * dev->nDataBytesPerChunk;
5425
5426                                 foundChunksInBlock = 1;
5427
5428
5429                                 yaffs_SetChunkBit(dev, blk, c);
5430                                 bi->pagesInUse++;
5431
5432                                 in = yaffs_FindOrCreateObjectByNumber(dev,
5433                                                                       tags.
5434                                                                       objectId,
5435                                                                       YAFFS_OBJECT_TYPE_FILE);
5436                                 if (in->variantType == YAFFS_OBJECT_TYPE_FILE
5437                                     && chunkBase <
5438                                     in->variant.fileVariant.shrinkSize) {
5439                                         /* This has not been invalidated by a resize */
5440                                         yaffs_PutChunkIntoFile(in, tags.chunkId,
5441                                                                chunk, -1);
5442
5443                                         /* File size is calculated by looking at the data chunks if we have not
5444                                          * seen an object header yet. Stop this practice once we find an object header.
5445                                          */
5446                                         endpos =
5447                                             (tags.chunkId -
5448                                              1) * dev->nDataBytesPerChunk +
5449                                             tags.byteCount;
5450
5451                                         if (!in->valid &&       /* have not got an object header yet */
5452                                             in->variant.fileVariant.
5453                                             scannedFileSize < endpos) {
5454                                                 in->variant.fileVariant.
5455                                                     scannedFileSize = endpos;
5456                                                 in->variant.fileVariant.
5457                                                     fileSize =
5458                                                     in->variant.fileVariant.
5459                                                     scannedFileSize;
5460                                         }
5461
5462                                 } else {
5463                                         /* This chunk has been invalidated by a resize, so delete */
5464                                         yaffs_DeleteChunk(dev, chunk, 1, __LINE__);
5465
5466                                 }
5467                         } else {
5468                                 /* chunkId == 0, so it is an ObjectHeader.
5469                                  * Thus, we read in the object header and make the object
5470                                  */
5471                                 foundChunksInBlock = 1;
5472
5473                                 yaffs_SetChunkBit(dev, blk, c);
5474                                 bi->pagesInUse++;
5475
5476                                 oh = NULL;
5477                                 in = NULL;
5478
5479                                 if (tags.extraHeaderInfoAvailable) {
5480                                         in = yaffs_FindOrCreateObjectByNumber
5481                                             (dev, tags.objectId,
5482                                              tags.extraObjectType);
5483                                 }
5484
5485                                 if (!in ||
5486 #ifdef CONFIG_YAFFS_DISABLE_LAZY_LOAD
5487                                     !in->valid ||
5488 #endif
5489                                     tags.extraShadows ||
5490                                     (!in->valid &&
5491                                     (tags.objectId == YAFFS_OBJECTID_ROOT ||
5492                                      tags.objectId == YAFFS_OBJECTID_LOSTNFOUND))
5493                                     ) {
5494
5495                                         /* If we don't have  valid info then we need to read the chunk
5496                                          * TODO In future we can probably defer reading the chunk and
5497                                          * living with invalid data until needed.
5498                                          */
5499
5500                                         result = yaffs_ReadChunkWithTagsFromNAND(dev,
5501                                                                         chunk,
5502                                                                         chunkData,
5503                                                                         NULL);
5504
5505                                         oh = (yaffs_ObjectHeader *) chunkData;
5506
5507                                         if (!in)
5508                                                 in = yaffs_FindOrCreateObjectByNumber(dev, tags.objectId, oh->type);
5509
5510                                 }
5511
5512                                 if (!in) {
5513                                         /* TODO Hoosterman we have a problem! */
5514                                         T(YAFFS_TRACE_ERROR,
5515                                           (TSTR
5516                                            ("yaffs tragedy: Could not make object for object  %d  "
5517                                             "at chunk %d during scan"
5518                                             TENDSTR), tags.objectId, chunk));
5519
5520                                 }
5521
5522                                 if (in->valid) {
5523                                         /* We have already filled this one.
5524                                          * We have a duplicate that will be discarded, but
5525                                          * we first have to suck out resize info if it is a file.
5526                                          */
5527
5528                                         if ((in->variantType == YAFFS_OBJECT_TYPE_FILE) &&
5529                                              ((oh &&
5530                                                oh-> type == YAFFS_OBJECT_TYPE_FILE)||
5531                                               (tags.extraHeaderInfoAvailable  &&
5532                                                tags.extraObjectType == YAFFS_OBJECT_TYPE_FILE))
5533                                             ) {
5534                                                 __u32 thisSize =
5535                                                     (oh) ? oh->fileSize : tags.
5536                                                     extraFileLength;
5537                                                 __u32 parentObjectId =
5538                                                     (oh) ? oh->
5539                                                     parentObjectId : tags.
5540                                                     extraParentObjectId;
5541                                                 unsigned isShrink =
5542                                                     (oh) ? oh->isShrink : tags.
5543                                                     extraIsShrinkHeader;
5544
5545                                                 /* If it is deleted (unlinked at start also means deleted)
5546                                                  * we treat the file size as being zeroed at this point.
5547                                                  */
5548                                                 if (parentObjectId ==
5549                                                     YAFFS_OBJECTID_DELETED
5550                                                     || parentObjectId ==
5551                                                     YAFFS_OBJECTID_UNLINKED) {
5552                                                         thisSize = 0;
5553                                                         isShrink = 1;
5554                                                 }
5555
5556                                                 if (isShrink &&
5557                                                     in->variant.fileVariant.
5558                                                     shrinkSize > thisSize) {
5559                                                         in->variant.fileVariant.
5560                                                             shrinkSize =
5561                                                             thisSize;
5562                                                 }
5563
5564                                                 if (isShrink) {
5565                                                         bi->hasShrinkHeader = 1;
5566                                                 }
5567
5568                                         }
5569                                         /* Use existing - destroy this one. */
5570                                         yaffs_DeleteChunk(dev, chunk, 1, __LINE__);
5571
5572                                 }
5573
5574                                 if (!in->valid &&
5575                                     (tags.objectId == YAFFS_OBJECTID_ROOT ||
5576                                      tags.objectId ==
5577                                      YAFFS_OBJECTID_LOSTNFOUND)) {
5578                                         /* We only load some info, don't fiddle with directory structure */
5579                                         in->valid = 1;
5580
5581                                         if(oh) {
5582                                                 in->variantType = oh->type;
5583
5584                                                 in->yst_mode = oh->yst_mode;
5585 #ifdef CONFIG_YAFFS_WINCE
5586                                                 in->win_atime[0] = oh->win_atime[0];
5587                                                 in->win_ctime[0] = oh->win_ctime[0];
5588                                                 in->win_mtime[0] = oh->win_mtime[0];
5589                                                 in->win_atime[1] = oh->win_atime[1];
5590                                                 in->win_ctime[1] = oh->win_ctime[1];
5591                                                 in->win_mtime[1] = oh->win_mtime[1];
5592 #else
5593                                                 in->yst_uid = oh->yst_uid;
5594                                                 in->yst_gid = oh->yst_gid;
5595                                                 in->yst_atime = oh->yst_atime;
5596                                                 in->yst_mtime = oh->yst_mtime;
5597                                                 in->yst_ctime = oh->yst_ctime;
5598                                                 in->yst_rdev = oh->yst_rdev;
5599
5600 #endif
5601                                         } else {
5602                                                 in->variantType = tags.extraObjectType;
5603                                                 in->lazyLoaded = 1;
5604                                         }
5605
5606                                         in->chunkId = chunk;
5607
5608                                 } else if (!in->valid) {
5609                                         /* we need to load this info */
5610
5611                                         in->valid = 1;
5612                                         in->chunkId = chunk;
5613
5614                                         if(oh) {
5615                                                 in->variantType = oh->type;
5616
5617                                                 in->yst_mode = oh->yst_mode;
5618 #ifdef CONFIG_YAFFS_WINCE
5619                                                 in->win_atime[0] = oh->win_atime[0];
5620                                                 in->win_ctime[0] = oh->win_ctime[0];
5621                                                 in->win_mtime[0] = oh->win_mtime[0];
5622                                                 in->win_atime[1] = oh->win_atime[1];
5623                                                 in->win_ctime[1] = oh->win_ctime[1];
5624                                                 in->win_mtime[1] = oh->win_mtime[1];
5625 #else
5626                                                 in->yst_uid = oh->yst_uid;
5627                                                 in->yst_gid = oh->yst_gid;
5628                                                 in->yst_atime = oh->yst_atime;
5629                                                 in->yst_mtime = oh->yst_mtime;
5630                                                 in->yst_ctime = oh->yst_ctime;
5631                                                 in->yst_rdev = oh->yst_rdev;
5632 #endif
5633
5634                                                 if (oh->shadowsObject > 0)
5635                                                         yaffs_HandleShadowedObject(dev,
5636                                                                            oh->
5637                                                                            shadowsObject,
5638                                                                            1);
5639
5640
5641                                                 yaffs_SetObjectName(in, oh->name);
5642                                                 parent =
5643                                                     yaffs_FindOrCreateObjectByNumber
5644                                                         (dev, oh->parentObjectId,
5645                                                          YAFFS_OBJECT_TYPE_DIRECTORY);
5646
5647                                                  fileSize = oh->fileSize;
5648                                                  isShrink = oh->isShrink;
5649                                                  equivalentObjectId = oh->equivalentObjectId;
5650
5651                                         }
5652                                         else {
5653                                                 in->variantType = tags.extraObjectType;
5654                                                 parent =
5655                                                     yaffs_FindOrCreateObjectByNumber
5656                                                         (dev, tags.extraParentObjectId,
5657                                                          YAFFS_OBJECT_TYPE_DIRECTORY);
5658                                                  fileSize = tags.extraFileLength;
5659                                                  isShrink = tags.extraIsShrinkHeader;
5660                                                  equivalentObjectId = tags.extraEquivalentObjectId;
5661                                                 in->lazyLoaded = 1;
5662
5663                                         }
5664                                         in->dirty = 0;
5665
5666                                         /* directory stuff...
5667                                          * hook up to parent
5668                                          */
5669
5670                                         if (parent->variantType ==
5671                                             YAFFS_OBJECT_TYPE_UNKNOWN) {
5672                                                 /* Set up as a directory */
5673                                                 parent->variantType =
5674                                                     YAFFS_OBJECT_TYPE_DIRECTORY;
5675                                                 INIT_LIST_HEAD(&parent->variant.
5676                                                                directoryVariant.
5677                                                                children);
5678                                         } else if (parent->variantType !=
5679                                                    YAFFS_OBJECT_TYPE_DIRECTORY)
5680                                         {
5681                                                 /* Hoosterman, another problem....
5682                                                  * We're trying to use a non-directory as a directory
5683                                                  */
5684
5685                                                 T(YAFFS_TRACE_ERROR,
5686                                                   (TSTR
5687                                                    ("yaffs tragedy: attempting to use non-directory as"
5688                                                     " a directory in scan. Put in lost+found."
5689                                                     TENDSTR)));
5690                                                 parent = dev->lostNFoundDir;
5691                                         }
5692
5693                                         yaffs_AddObjectToDirectory(parent, in);
5694
5695                                         itsUnlinked = (parent == dev->deletedDir) ||
5696                                                       (parent == dev->unlinkedDir);
5697
5698                                         if (isShrink) {
5699                                                 /* Mark the block as having a shrinkHeader */
5700                                                 bi->hasShrinkHeader = 1;
5701                                         }
5702
5703                                         /* Note re hardlinks.
5704                                          * Since we might scan a hardlink before its equivalent object is scanned
5705                                          * we put them all in a list.
5706                                          * After scanning is complete, we should have all the objects, so we run
5707                                          * through this list and fix up all the chains.
5708                                          */
5709
5710                                         switch (in->variantType) {
5711                                         case YAFFS_OBJECT_TYPE_UNKNOWN:
5712                                                 /* Todo got a problem */
5713                                                 break;
5714                                         case YAFFS_OBJECT_TYPE_FILE:
5715
5716                                                 if (in->variant.fileVariant.
5717                                                     scannedFileSize < fileSize) {
5718                                                         /* This covers the case where the file size is greater
5719                                                          * than where the data is
5720                                                          * This will happen if the file is resized to be larger
5721                                                          * than its current data extents.
5722                                                          */
5723                                                         in->variant.fileVariant.fileSize = fileSize;
5724                                                         in->variant.fileVariant.scannedFileSize =
5725                                                             in->variant.fileVariant.fileSize;
5726                                                 }
5727
5728                                                 if (isShrink &&
5729                                                     in->variant.fileVariant.shrinkSize > fileSize) {
5730                                                         in->variant.fileVariant.shrinkSize = fileSize;
5731                                                 }
5732
5733                                                 break;
5734                                         case YAFFS_OBJECT_TYPE_HARDLINK:
5735                                                 if(!itsUnlinked) {
5736                                                   in->variant.hardLinkVariant.equivalentObjectId =
5737                                                     equivalentObjectId;
5738                                                   in->hardLinks.next =
5739                                                     (struct list_head *) hardList;
5740                                                   hardList = in;
5741                                                 }
5742                                                 break;
5743                                         case YAFFS_OBJECT_TYPE_DIRECTORY:
5744                                                 /* Do nothing */
5745                                                 break;
5746                                         case YAFFS_OBJECT_TYPE_SPECIAL:
5747                                                 /* Do nothing */
5748                                                 break;
5749                                         case YAFFS_OBJECT_TYPE_SYMLINK:
5750                                                 if(oh)
5751                                                    in->variant.symLinkVariant.alias =
5752                                                     yaffs_CloneString(oh->
5753                                                                       alias);
5754                                                 break;
5755                                         }
5756
5757                                 }
5758                         }
5759                 }
5760
5761                 if (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING) {
5762                         /* If we got this far while scanning, then the block is fully allocated. */
5763                         state = YAFFS_BLOCK_STATE_FULL;
5764                 }
5765
5766                 bi->blockState = state;
5767
5768                 /* Now let's see if it was dirty */
5769                 if (bi->pagesInUse == 0 &&
5770                     !bi->hasShrinkHeader &&
5771                     bi->blockState == YAFFS_BLOCK_STATE_FULL) {
5772                         yaffs_BlockBecameDirty(dev, blk);
5773                 }
5774
5775         }
5776
5777         if (altBlockIndex)
5778                 YFREE_ALT(blockIndex);
5779         else
5780                 YFREE(blockIndex);
5781
5782         /* Ok, we've done all the scanning.
5783          * Fix up the hard link chains.
5784          * We should now have scanned all the objects, now it's time to add these
5785          * hardlinks.
5786          */
5787         yaffs_HardlinkFixup(dev,hardList);
5788
5789
5790         /*
5791         *  Sort out state of unlinked and deleted objects.
5792         */
5793         {
5794                 struct list_head *i;
5795                 struct list_head *n;
5796
5797                 yaffs_Object *l;
5798
5799                 /* Soft delete all the unlinked files */
5800                 list_for_each_safe(i, n,
5801                                    &dev->unlinkedDir->variant.directoryVariant.
5802                                    children) {
5803                         if (i) {
5804                                 l = list_entry(i, yaffs_Object, siblings);
5805                                 yaffs_DestroyObject(l);
5806                         }
5807                 }
5808
5809                 /* Soft delete all the deletedDir files */
5810                 list_for_each_safe(i, n,
5811                                    &dev->deletedDir->variant.directoryVariant.
5812                                    children) {
5813                         if (i) {
5814                                 l = list_entry(i, yaffs_Object, siblings);
5815                                 yaffs_DestroyObject(l);
5816
5817                         }
5818                 }
5819         }
5820
5821         yaffs_ReleaseTempBuffer(dev, chunkData, __LINE__);
5822
5823         T(YAFFS_TRACE_SCAN, (TSTR("yaffs_ScanBackwards ends" TENDSTR)));
5824
5825         return YAFFS_OK;
5826 }
5827
5828 /*------------------------------  Directory Functions ----------------------------- */
5829
5830 static void yaffs_RemoveObjectFromDirectory(yaffs_Object * obj)
5831 {
5832         yaffs_Device *dev = obj->myDev;
5833
5834         if(dev && dev->removeObjectCallback)
5835                 dev->removeObjectCallback(obj);
5836
5837         list_del_init(&obj->siblings);
5838         obj->parent = NULL;
5839 }
5840
5841
5842 static void yaffs_AddObjectToDirectory(yaffs_Object * directory,
5843                                        yaffs_Object * obj)
5844 {
5845
5846         if (!directory) {
5847                 T(YAFFS_TRACE_ALWAYS,
5848                   (TSTR
5849                    ("tragedy: Trying to add an object to a null pointer directory"
5850                     TENDSTR)));
5851                 YBUG();
5852         }
5853         if (directory->variantType != YAFFS_OBJECT_TYPE_DIRECTORY) {
5854                 T(YAFFS_TRACE_ALWAYS,
5855                   (TSTR
5856                    ("tragedy: Trying to add an object to a non-directory"
5857                     TENDSTR)));
5858                 YBUG();
5859         }
5860
5861         if (obj->siblings.prev == NULL) {
5862                 /* Not initialised */
5863                 INIT_LIST_HEAD(&obj->siblings);
5864
5865         } else if (!list_empty(&obj->siblings)) {
5866                 /* If it is holed up somewhere else, un hook it */
5867                 yaffs_RemoveObjectFromDirectory(obj);
5868         }
5869         /* Now add it */
5870         list_add(&obj->siblings, &directory->variant.directoryVariant.children);
5871         obj->parent = directory;
5872
5873         if (directory == obj->myDev->unlinkedDir
5874             || directory == obj->myDev->deletedDir) {
5875                 obj->unlinked = 1;
5876                 obj->myDev->nUnlinkedFiles++;
5877                 obj->renameAllowed = 0;
5878         }
5879 }
5880
5881 yaffs_Object *yaffs_FindObjectByName(yaffs_Object * directory,
5882                                      const YCHAR * name)
5883 {
5884         int sum;
5885
5886         struct list_head *i;
5887         YCHAR buffer[YAFFS_MAX_NAME_LENGTH + 1];
5888
5889         yaffs_Object *l;
5890
5891         if (!name) {
5892                 return NULL;
5893         }
5894
5895         if (!directory) {
5896                 T(YAFFS_TRACE_ALWAYS,
5897                   (TSTR
5898                    ("tragedy: yaffs_FindObjectByName: null pointer directory"
5899                     TENDSTR)));
5900                 YBUG();
5901         }
5902         if (directory->variantType != YAFFS_OBJECT_TYPE_DIRECTORY) {
5903                 T(YAFFS_TRACE_ALWAYS,
5904                   (TSTR
5905                    ("tragedy: yaffs_FindObjectByName: non-directory" TENDSTR)));
5906                 YBUG();
5907         }
5908
5909         sum = yaffs_CalcNameSum(name);
5910
5911         list_for_each(i, &directory->variant.directoryVariant.children) {
5912                 if (i) {
5913                         l = list_entry(i, yaffs_Object, siblings);
5914
5915                         yaffs_CheckObjectDetailsLoaded(l);
5916
5917                         /* Special case for lost-n-found */
5918                         if (l->objectId == YAFFS_OBJECTID_LOSTNFOUND) {
5919                                 if (yaffs_strcmp(name, YAFFS_LOSTNFOUND_NAME) == 0) {
5920                                         return l;
5921                                 }
5922                         } else if (yaffs_SumCompare(l->sum, sum) || l->chunkId <= 0)
5923                         {
5924                                 /* LostnFound cunk called Objxxx
5925                                  * Do a real check
5926                                  */
5927                                 yaffs_GetObjectName(l, buffer,
5928                                                     YAFFS_MAX_NAME_LENGTH);
5929                                 if (yaffs_strcmp(name, buffer) == 0) {
5930                                         return l;
5931                                 }
5932
5933                         }
5934                 }
5935         }
5936
5937         return NULL;
5938 }
5939
5940
5941 #if 0
5942 int yaffs_ApplyToDirectoryChildren(yaffs_Object * theDir,
5943                                    int (*fn) (yaffs_Object *))
5944 {
5945         struct list_head *i;
5946         yaffs_Object *l;
5947
5948         if (!theDir) {
5949                 T(YAFFS_TRACE_ALWAYS,
5950                   (TSTR
5951                    ("tragedy: yaffs_FindObjectByName: null pointer directory"
5952                     TENDSTR)));
5953                 YBUG();
5954         }
5955         if (theDir->variantType != YAFFS_OBJECT_TYPE_DIRECTORY) {
5956                 T(YAFFS_TRACE_ALWAYS,
5957                   (TSTR
5958                    ("tragedy: yaffs_FindObjectByName: non-directory" TENDSTR)));
5959                 YBUG();
5960         }
5961
5962         list_for_each(i, &theDir->variant.directoryVariant.children) {
5963                 if (i) {
5964                         l = list_entry(i, yaffs_Object, siblings);
5965                         if (l && !fn(l)) {
5966                                 return YAFFS_FAIL;
5967                         }
5968                 }
5969         }
5970
5971         return YAFFS_OK;
5972
5973 }
5974 #endif
5975
5976 /* GetEquivalentObject dereferences any hard links to get to the
5977  * actual object.
5978  */
5979
5980 yaffs_Object *yaffs_GetEquivalentObject(yaffs_Object * obj)
5981 {
5982         if (obj && obj->variantType == YAFFS_OBJECT_TYPE_HARDLINK) {
5983                 /* We want the object id of the equivalent object, not this one */
5984                 obj = obj->variant.hardLinkVariant.equivalentObject;
5985         }
5986         return obj;
5987
5988 }
5989
5990 int yaffs_GetObjectName(yaffs_Object * obj, YCHAR * name, int buffSize)
5991 {
5992         memset(name, 0, buffSize * sizeof(YCHAR));
5993
5994         yaffs_CheckObjectDetailsLoaded(obj);
5995
5996         if (obj->objectId == YAFFS_OBJECTID_LOSTNFOUND) {
5997                 yaffs_strncpy(name, YAFFS_LOSTNFOUND_NAME, buffSize - 1);
5998         } else if (obj->chunkId <= 0) {
5999                 YCHAR locName[20];
6000                 /* make up a name */
6001                 yaffs_sprintf(locName, _Y("%s%d"), YAFFS_LOSTNFOUND_PREFIX,
6002                               obj->objectId);
6003                 yaffs_strncpy(name, locName, buffSize - 1);
6004
6005         }
6006 #ifdef CONFIG_YAFFS_SHORT_NAMES_IN_RAM
6007         else if (obj->shortName[0]) {
6008                 yaffs_strcpy(name, obj->shortName);
6009         }
6010 #endif
6011         else {
6012                 int result;
6013                 __u8 *buffer = yaffs_GetTempBuffer(obj->myDev, __LINE__);
6014
6015                 yaffs_ObjectHeader *oh = (yaffs_ObjectHeader *) buffer;
6016
6017                 memset(buffer, 0, obj->myDev->nDataBytesPerChunk);
6018
6019                 if (obj->chunkId >= 0) {
6020                         result = yaffs_ReadChunkWithTagsFromNAND(obj->myDev,
6021                                                         obj->chunkId, buffer,
6022                                                         NULL);
6023                 }
6024                 yaffs_strncpy(name, oh->name, buffSize - 1);
6025
6026                 yaffs_ReleaseTempBuffer(obj->myDev, buffer, __LINE__);
6027         }
6028
6029         return yaffs_strlen(name);
6030 }
6031
6032 int yaffs_GetObjectFileLength(yaffs_Object * obj)
6033 {
6034
6035         /* Dereference any hard linking */
6036         obj = yaffs_GetEquivalentObject(obj);
6037
6038         if (obj->variantType == YAFFS_OBJECT_TYPE_FILE) {
6039                 return obj->variant.fileVariant.fileSize;
6040         }
6041         if (obj->variantType == YAFFS_OBJECT_TYPE_SYMLINK) {
6042                 return yaffs_strlen(obj->variant.symLinkVariant.alias);
6043         } else {
6044                 /* Only a directory should drop through to here */
6045                 return obj->myDev->nDataBytesPerChunk;
6046         }
6047 }
6048
6049 int yaffs_GetObjectLinkCount(yaffs_Object * obj)
6050 {
6051         int count = 0;
6052         struct list_head *i;
6053
6054         if (!obj->unlinked) {
6055                 count++;        /* the object itself */
6056         }
6057         list_for_each(i, &obj->hardLinks) {
6058                 count++;        /* add the hard links; */
6059         }
6060         return count;
6061
6062 }
6063
6064 int yaffs_GetObjectInode(yaffs_Object * obj)
6065 {
6066         obj = yaffs_GetEquivalentObject(obj);
6067
6068         return obj->objectId;
6069 }
6070
6071 unsigned yaffs_GetObjectType(yaffs_Object * obj)
6072 {
6073         obj = yaffs_GetEquivalentObject(obj);
6074
6075         switch (obj->variantType) {
6076         case YAFFS_OBJECT_TYPE_FILE:
6077                 return DT_REG;
6078                 break;
6079         case YAFFS_OBJECT_TYPE_DIRECTORY:
6080                 return DT_DIR;
6081                 break;
6082         case YAFFS_OBJECT_TYPE_SYMLINK:
6083                 return DT_LNK;
6084                 break;
6085         case YAFFS_OBJECT_TYPE_HARDLINK:
6086                 return DT_REG;
6087                 break;
6088         case YAFFS_OBJECT_TYPE_SPECIAL:
6089                 if (S_ISFIFO(obj->yst_mode))
6090                         return DT_FIFO;
6091                 if (S_ISCHR(obj->yst_mode))
6092                         return DT_CHR;
6093                 if (S_ISBLK(obj->yst_mode))
6094                         return DT_BLK;
6095                 if (S_ISSOCK(obj->yst_mode))
6096                         return DT_SOCK;
6097         default:
6098                 return DT_REG;
6099                 break;
6100         }
6101 }
6102
6103 YCHAR *yaffs_GetSymlinkAlias(yaffs_Object * obj)
6104 {
6105         obj = yaffs_GetEquivalentObject(obj);
6106         if (obj->variantType == YAFFS_OBJECT_TYPE_SYMLINK) {
6107                 return yaffs_CloneString(obj->variant.symLinkVariant.alias);
6108         } else {
6109                 return yaffs_CloneString(_Y(""));
6110         }
6111 }
6112
6113 #ifndef CONFIG_YAFFS_WINCE
6114
6115 int yaffs_SetAttributes(yaffs_Object * obj, struct iattr *attr)
6116 {
6117         unsigned int valid = attr->ia_valid;
6118
6119         if (valid & ATTR_MODE)
6120                 obj->yst_mode = attr->ia_mode;
6121         if (valid & ATTR_UID)
6122                 obj->yst_uid = attr->ia_uid;
6123         if (valid & ATTR_GID)
6124                 obj->yst_gid = attr->ia_gid;
6125
6126         if (valid & ATTR_ATIME)
6127                 obj->yst_atime = Y_TIME_CONVERT(attr->ia_atime);
6128         if (valid & ATTR_CTIME)
6129                 obj->yst_ctime = Y_TIME_CONVERT(attr->ia_ctime);
6130         if (valid & ATTR_MTIME)
6131                 obj->yst_mtime = Y_TIME_CONVERT(attr->ia_mtime);
6132
6133         if (valid & ATTR_SIZE)
6134                 yaffs_ResizeFile(obj, attr->ia_size);
6135
6136         yaffs_UpdateObjectHeader(obj, NULL, 1, 0, 0);
6137
6138         return YAFFS_OK;
6139
6140 }
6141 int yaffs_GetAttributes(yaffs_Object * obj, struct iattr *attr)
6142 {
6143         unsigned int valid = 0;
6144
6145         attr->ia_mode = obj->yst_mode;
6146         valid |= ATTR_MODE;
6147         attr->ia_uid = obj->yst_uid;
6148         valid |= ATTR_UID;
6149         attr->ia_gid = obj->yst_gid;
6150         valid |= ATTR_GID;
6151
6152         Y_TIME_CONVERT(attr->ia_atime) = obj->yst_atime;
6153         valid |= ATTR_ATIME;
6154         Y_TIME_CONVERT(attr->ia_ctime) = obj->yst_ctime;
6155         valid |= ATTR_CTIME;
6156         Y_TIME_CONVERT(attr->ia_mtime) = obj->yst_mtime;
6157         valid |= ATTR_MTIME;
6158
6159         attr->ia_size = yaffs_GetFileSize(obj);
6160         valid |= ATTR_SIZE;
6161
6162         attr->ia_valid = valid;
6163
6164         return YAFFS_OK;
6165
6166 }
6167
6168 #endif
6169
6170 #if 0
6171 int yaffs_DumpObject(yaffs_Object * obj)
6172 {
6173         YCHAR name[257];
6174
6175         yaffs_GetObjectName(obj, name, 256);
6176
6177         T(YAFFS_TRACE_ALWAYS,
6178           (TSTR
6179            ("Object %d, inode %d \"%s\"\n dirty %d valid %d serial %d sum %d"
6180             " chunk %d type %d size %d\n"
6181             TENDSTR), obj->objectId, yaffs_GetObjectInode(obj), name,
6182            obj->dirty, obj->valid, obj->serial, obj->sum, obj->chunkId,
6183            yaffs_GetObjectType(obj), yaffs_GetObjectFileLength(obj)));
6184
6185         return YAFFS_OK;
6186 }
6187 #endif
6188
6189 /*---------------------------- Initialisation code -------------------------------------- */
6190
6191 static int yaffs_CheckDevFunctions(const yaffs_Device * dev)
6192 {
6193
6194         /* Common functions, gotta have */
6195         if (!dev->eraseBlockInNAND || !dev->initialiseNAND)
6196                 return 0;
6197
6198 #ifdef CONFIG_YAFFS_YAFFS2
6199
6200         /* Can use the "with tags" style interface for yaffs1 or yaffs2 */
6201         if (dev->writeChunkWithTagsToNAND &&
6202             dev->readChunkWithTagsFromNAND &&
6203             !dev->writeChunkToNAND &&
6204             !dev->readChunkFromNAND &&
6205             dev->markNANDBlockBad && dev->queryNANDBlock)
6206                 return 1;
6207 #endif
6208
6209         /* Can use the "spare" style interface for yaffs1 */
6210         if (!dev->isYaffs2 &&
6211             !dev->writeChunkWithTagsToNAND &&
6212             !dev->readChunkWithTagsFromNAND &&
6213             dev->writeChunkToNAND &&
6214             dev->readChunkFromNAND &&
6215             !dev->markNANDBlockBad && !dev->queryNANDBlock)
6216                 return 1;
6217
6218         return 0;               /* bad */
6219 }
6220
6221
6222 static void yaffs_CreateInitialDirectories(yaffs_Device *dev)
6223 {
6224         /* Initialise the unlinked, deleted, root and lost and found directories */
6225
6226         dev->lostNFoundDir = dev->rootDir =  NULL;
6227         dev->unlinkedDir = dev->deletedDir = NULL;
6228
6229         dev->unlinkedDir =
6230             yaffs_CreateFakeDirectory(dev, YAFFS_OBJECTID_UNLINKED, S_IFDIR);
6231         dev->deletedDir =
6232             yaffs_CreateFakeDirectory(dev, YAFFS_OBJECTID_DELETED, S_IFDIR);
6233
6234         dev->rootDir =
6235             yaffs_CreateFakeDirectory(dev, YAFFS_OBJECTID_ROOT,
6236                                       YAFFS_ROOT_MODE | S_IFDIR);
6237         dev->lostNFoundDir =
6238             yaffs_CreateFakeDirectory(dev, YAFFS_OBJECTID_LOSTNFOUND,
6239                                       YAFFS_LOSTNFOUND_MODE | S_IFDIR);
6240         yaffs_AddObjectToDirectory(dev->rootDir, dev->lostNFoundDir);
6241 }
6242
6243 int yaffs_GutsInitialise(yaffs_Device * dev)
6244 {
6245         unsigned x;
6246         int bits;
6247
6248         T(YAFFS_TRACE_TRACING, (TSTR("yaffs: yaffs_GutsInitialise()" TENDSTR)));
6249
6250         /* Check stuff that must be set */
6251
6252         if (!dev) {
6253                 T(YAFFS_TRACE_ALWAYS, (TSTR("yaffs: Need a device" TENDSTR)));
6254                 return YAFFS_FAIL;
6255         }
6256
6257         dev->internalStartBlock = dev->startBlock;
6258         dev->internalEndBlock = dev->endBlock;
6259         dev->blockOffset = 0;
6260         dev->chunkOffset = 0;
6261         dev->nFreeChunks = 0;
6262
6263         if (dev->startBlock == 0) {
6264                 dev->internalStartBlock = dev->startBlock + 1;
6265                 dev->internalEndBlock = dev->endBlock + 1;
6266                 dev->blockOffset = 1;
6267                 dev->chunkOffset = dev->nChunksPerBlock;
6268         }
6269
6270         /* Check geometry parameters. */
6271
6272         if ((dev->isYaffs2 && dev->nDataBytesPerChunk < 1024) ||
6273             (!dev->isYaffs2 && dev->nDataBytesPerChunk != 512) ||
6274              dev->nChunksPerBlock < 2 ||
6275              dev->nReservedBlocks < 2 ||
6276              dev->internalStartBlock <= 0 ||
6277              dev->internalEndBlock <= 0 ||
6278              dev->internalEndBlock <= (dev->internalStartBlock + dev->nReservedBlocks + 2)      // otherwise it is too small
6279             ) {
6280                 T(YAFFS_TRACE_ALWAYS,
6281                   (TSTR
6282                    ("yaffs: NAND geometry problems: chunk size %d, type is yaffs%s "
6283                     TENDSTR), dev->nDataBytesPerChunk, dev->isYaffs2 ? "2" : ""));
6284                 return YAFFS_FAIL;
6285         }
6286
6287         if (yaffs_InitialiseNAND(dev) != YAFFS_OK) {
6288                 T(YAFFS_TRACE_ALWAYS,
6289                   (TSTR("yaffs: InitialiseNAND failed" TENDSTR)));
6290                 return YAFFS_FAIL;
6291         }
6292
6293         /* Got the right mix of functions? */
6294         if (!yaffs_CheckDevFunctions(dev)) {
6295                 /* Function missing */
6296                 T(YAFFS_TRACE_ALWAYS,
6297                   (TSTR
6298                    ("yaffs: device function(s) missing or wrong\n" TENDSTR)));
6299
6300                 return YAFFS_FAIL;
6301         }
6302
6303         /* This is really a compilation check. */
6304         if (!yaffs_CheckStructures()) {
6305                 T(YAFFS_TRACE_ALWAYS,
6306                   (TSTR("yaffs_CheckStructures failed\n" TENDSTR)));
6307                 return YAFFS_FAIL;
6308         }
6309
6310         if (dev->isMounted) {
6311                 T(YAFFS_TRACE_ALWAYS,
6312                   (TSTR("yaffs: device already mounted\n" TENDSTR)));
6313                 return YAFFS_FAIL;
6314         }
6315
6316         /* Finished with most checks. One or two more checks happen later on too. */
6317
6318         dev->isMounted = 1;
6319
6320
6321
6322         /* OK now calculate a few things for the device */
6323
6324         /*
6325          *  Calculate all the chunk size manipulation numbers:
6326          */
6327          /* Start off assuming it is a power of 2 */
6328          dev->chunkShift = ShiftDiv(dev->nDataBytesPerChunk);
6329          dev->chunkMask = (1<<dev->chunkShift) - 1;
6330
6331          if(dev->nDataBytesPerChunk == (dev->chunkMask + 1)){
6332                 /* Yes it is a power of 2, disable crumbs */
6333                 dev->crumbMask = 0;
6334                 dev->crumbShift = 0;
6335                 dev->crumbsPerChunk = 0;
6336          } else {
6337                 /* Not a power of 2, use crumbs instead */
6338                 dev->crumbShift = ShiftDiv(sizeof(yaffs_PackedTags2TagsPart));
6339                 dev->crumbMask = (1<<dev->crumbShift)-1;
6340                 dev->crumbsPerChunk = dev->nDataBytesPerChunk/(1 << dev->crumbShift);
6341                 dev->chunkShift = 0;
6342                 dev->chunkMask = 0;
6343         }
6344
6345
6346         /*
6347          * Calculate chunkGroupBits.
6348          * We need to find the next power of 2 > than internalEndBlock
6349          */
6350
6351         x = dev->nChunksPerBlock * (dev->internalEndBlock + 1);
6352
6353         bits = ShiftsGE(x);
6354
6355         /* Set up tnode width if wide tnodes are enabled. */
6356         if(!dev->wideTnodesDisabled){
6357                 /* bits must be even so that we end up with 32-bit words */
6358                 if(bits & 1)
6359                         bits++;
6360                 if(bits < 16)
6361                         dev->tnodeWidth = 16;
6362                 else
6363                         dev->tnodeWidth = bits;
6364         }
6365         else
6366                 dev->tnodeWidth = 16;
6367
6368         dev->tnodeMask = (1<<dev->tnodeWidth)-1;
6369
6370         /* Level0 Tnodes are 16 bits or wider (if wide tnodes are enabled),
6371          * so if the bitwidth of the
6372          * chunk range we're using is greater than 16 we need
6373          * to figure out chunk shift and chunkGroupSize
6374          */
6375
6376         if (bits <= dev->tnodeWidth)
6377                 dev->chunkGroupBits = 0;
6378         else
6379                 dev->chunkGroupBits = bits - dev->tnodeWidth;
6380
6381
6382         dev->chunkGroupSize = 1 << dev->chunkGroupBits;
6383
6384         if (dev->nChunksPerBlock < dev->chunkGroupSize) {
6385                 /* We have a problem because the soft delete won't work if
6386                  * the chunk group size > chunks per block.
6387                  * This can be remedied by using larger "virtual blocks".
6388                  */
6389                 T(YAFFS_TRACE_ALWAYS,
6390                   (TSTR("yaffs: chunk group too large\n" TENDSTR)));
6391
6392                 return YAFFS_FAIL;
6393         }
6394
6395         /* OK, we've finished verifying the device, lets continue with initialisation */
6396
6397         /* More device initialisation */
6398         dev->garbageCollections = 0;
6399         dev->passiveGarbageCollections = 0;
6400         dev->currentDirtyChecker = 0;
6401         dev->bufferedBlock = -1;
6402         dev->doingBufferedBlockRewrite = 0;
6403         dev->nDeletedFiles = 0;
6404         dev->nBackgroundDeletions = 0;
6405         dev->nUnlinkedFiles = 0;
6406         dev->eccFixed = 0;
6407         dev->eccUnfixed = 0;
6408         dev->tagsEccFixed = 0;
6409         dev->tagsEccUnfixed = 0;
6410         dev->nErasureFailures = 0;
6411         dev->nErasedBlocks = 0;
6412         dev->isDoingGC = 0;
6413         dev->hasPendingPrioritisedGCs = 1; /* Assume the worst for now, will get fixed on first GC */
6414
6415         /* Initialise temporary buffers and caches. */
6416         {
6417                 int i;
6418                 for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
6419                         dev->tempBuffer[i].line = 0;    /* not in use */
6420                         dev->tempBuffer[i].buffer =
6421                             YMALLOC_DMA(dev->nDataBytesPerChunk);
6422                 }
6423         }
6424
6425         if (dev->nShortOpCaches > 0) {
6426                 int i;
6427
6428                 if (dev->nShortOpCaches > YAFFS_MAX_SHORT_OP_CACHES) {
6429                         dev->nShortOpCaches = YAFFS_MAX_SHORT_OP_CACHES;
6430                 }
6431
6432                 dev->srCache =
6433                     YMALLOC(dev->nShortOpCaches * sizeof(yaffs_ChunkCache));
6434
6435                 for (i = 0; i < dev->nShortOpCaches; i++) {
6436                         dev->srCache[i].object = NULL;
6437                         dev->srCache[i].lastUse = 0;
6438                         dev->srCache[i].dirty = 0;
6439                         dev->srCache[i].data = YMALLOC_DMA(dev->nDataBytesPerChunk);
6440                 }
6441                 dev->srLastUse = 0;
6442         }
6443
6444         dev->cacheHits = 0;
6445
6446         dev->gcCleanupList = YMALLOC(dev->nChunksPerBlock * sizeof(__u32));
6447
6448         if (dev->isYaffs2) {
6449                 dev->useHeaderFileSize = 1;
6450         }
6451
6452         yaffs_InitialiseBlocks(dev);
6453         yaffs_InitialiseTnodes(dev);
6454         yaffs_InitialiseObjects(dev);
6455
6456         yaffs_CreateInitialDirectories(dev);
6457
6458
6459         /* Now scan the flash. */
6460         if (dev->isYaffs2) {
6461                 if(yaffs_CheckpointRestore(dev)) {
6462                         T(YAFFS_TRACE_ALWAYS,
6463                           (TSTR("yaffs: restored from checkpoint" TENDSTR)));
6464                 } else {
6465
6466                         /* Clean up the mess caused by an aborted checkpoint load
6467                          * and scan backwards.
6468                          */
6469                         yaffs_DeinitialiseBlocks(dev);
6470                         yaffs_DeinitialiseTnodes(dev);
6471                         yaffs_DeinitialiseObjects(dev);
6472                         yaffs_InitialiseBlocks(dev);
6473                         yaffs_InitialiseTnodes(dev);
6474                         yaffs_InitialiseObjects(dev);
6475                         yaffs_CreateInitialDirectories(dev);
6476
6477                         yaffs_ScanBackwards(dev);
6478                 }
6479         }else
6480                 yaffs_Scan(dev);
6481
6482         /* Zero out stats */
6483         dev->nPageReads = 0;
6484         dev->nPageWrites = 0;
6485         dev->nBlockErasures = 0;
6486         dev->nGCCopies = 0;
6487         dev->nRetriedWrites = 0;
6488
6489         dev->nRetiredBlocks = 0;
6490
6491         yaffs_VerifyFreeChunks(dev);
6492
6493         T(YAFFS_TRACE_TRACING,
6494           (TSTR("yaffs: yaffs_GutsInitialise() done.\n" TENDSTR)));
6495         return YAFFS_OK;
6496
6497 }
6498
6499 void yaffs_Deinitialise(yaffs_Device * dev)
6500 {
6501         if (dev->isMounted) {
6502                 int i;
6503
6504                 yaffs_DeinitialiseBlocks(dev);
6505                 yaffs_DeinitialiseTnodes(dev);
6506                 yaffs_DeinitialiseObjects(dev);
6507                 if (dev->nShortOpCaches > 0) {
6508
6509                         for (i = 0; i < dev->nShortOpCaches; i++) {
6510                                 YFREE(dev->srCache[i].data);
6511                         }
6512
6513                         YFREE(dev->srCache);
6514                 }
6515
6516                 YFREE(dev->gcCleanupList);
6517
6518                 for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
6519                         YFREE(dev->tempBuffer[i].buffer);
6520                 }
6521
6522                 dev->isMounted = 0;
6523         }
6524
6525 }
6526
6527 static int yaffs_CountFreeChunks(yaffs_Device * dev)
6528 {
6529         int nFree;
6530         int b;
6531
6532         yaffs_BlockInfo *blk;
6533
6534         for (nFree = 0, b = dev->internalStartBlock; b <= dev->internalEndBlock;
6535              b++) {
6536                 blk = yaffs_GetBlockInfo(dev, b);
6537
6538                 switch (blk->blockState) {
6539                 case YAFFS_BLOCK_STATE_EMPTY:
6540                 case YAFFS_BLOCK_STATE_ALLOCATING:
6541                 case YAFFS_BLOCK_STATE_COLLECTING:
6542                 case YAFFS_BLOCK_STATE_FULL:
6543                         nFree +=
6544                             (dev->nChunksPerBlock - blk->pagesInUse +
6545                              blk->softDeletions);
6546                         break;
6547                 default:
6548                         break;
6549                 }
6550
6551         }
6552
6553         return nFree;
6554 }
6555
6556 int yaffs_GetNumberOfFreeChunks(yaffs_Device * dev)
6557 {
6558         /* This is what we report to the outside world */
6559
6560         int nFree;
6561         int nDirtyCacheChunks;
6562         int blocksForCheckpoint;
6563
6564 #if 1
6565         nFree = dev->nFreeChunks;
6566 #else
6567         nFree = yaffs_CountFreeChunks(dev);
6568 #endif
6569
6570         nFree += dev->nDeletedFiles;
6571
6572         /* Now count the number of dirty chunks in the cache and subtract those */
6573
6574         {
6575                 int i;
6576                 for (nDirtyCacheChunks = 0, i = 0; i < dev->nShortOpCaches; i++) {
6577                         if (dev->srCache[i].dirty)
6578                                 nDirtyCacheChunks++;
6579                 }
6580         }
6581
6582         nFree -= nDirtyCacheChunks;
6583
6584         nFree -= ((dev->nReservedBlocks + 1) * dev->nChunksPerBlock);
6585
6586         /* Now we figure out how much to reserve for the checkpoint and report that... */
6587         blocksForCheckpoint = dev->nCheckpointReservedBlocks - dev->blocksInCheckpoint;
6588         if(blocksForCheckpoint < 0)
6589                 blocksForCheckpoint = 0;
6590
6591         nFree -= (blocksForCheckpoint * dev->nChunksPerBlock);
6592
6593         if (nFree < 0)
6594                 nFree = 0;
6595
6596         return nFree;
6597
6598 }
6599
6600 static int yaffs_freeVerificationFailures;
6601
6602 static void yaffs_VerifyFreeChunks(yaffs_Device * dev)
6603 {
6604         int counted = yaffs_CountFreeChunks(dev);
6605
6606         int difference = dev->nFreeChunks - counted;
6607
6608         if (difference) {
6609                 T(YAFFS_TRACE_ALWAYS,
6610                   (TSTR("Freechunks verification failure %d %d %d" TENDSTR),
6611                    dev->nFreeChunks, counted, difference));
6612                 yaffs_freeVerificationFailures++;
6613         }
6614 }
6615
6616 /*---------------------------------------- YAFFS test code ----------------------*/
6617
6618 #define yaffs_CheckStruct(structure,syze, name) \
6619            if(sizeof(structure) != syze) \
6620                { \
6621                  T(YAFFS_TRACE_ALWAYS,(TSTR("%s should be %d but is %d\n" TENDSTR),\
6622                  name,syze,sizeof(structure))); \
6623                  return YAFFS_FAIL; \
6624                 }
6625
6626 static int yaffs_CheckStructures(void)
6627 {
6628 /*      yaffs_CheckStruct(yaffs_Tags,8,"yaffs_Tags") */
6629 /*      yaffs_CheckStruct(yaffs_TagsUnion,8,"yaffs_TagsUnion") */
6630 /*      yaffs_CheckStruct(yaffs_Spare,16,"yaffs_Spare") */
6631 #ifndef CONFIG_YAFFS_TNODE_LIST_DEBUG
6632         yaffs_CheckStruct(yaffs_Tnode, 2 * YAFFS_NTNODES_LEVEL0, "yaffs_Tnode")
6633 #endif
6634             yaffs_CheckStruct(yaffs_ObjectHeader, 512, "yaffs_ObjectHeader")
6635
6636             return YAFFS_OK;
6637 }