yaffs_guts.c

   1 /*
   2  * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
   3  *
   4  * Copyright (C) 2002-2007 Aleph One Ltd.
   5  *   for Toby Churchill Ltd and Brightstar Engineering
   6  *
   7  * Created by Charles Manning <charles@aleph1.co.uk>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2 as
  11  * published by the Free Software Foundation.
  12  */
  13
  14 const char *yaffs_guts_c_version =
  15     "$Id: yaffs_guts.c,v 1.47 2007-02-14 01:09:06 wookey Exp $";
  16
  17 #include "yportenv.h"
  18
  19 #include "yaffsinterface.h"
  20 #include "yaffs_guts.h"
  21 #include "yaffs_tagsvalidity.h"
  22
  23 #include "yaffs_tagscompat.h"
  24 #ifndef CONFIG_YAFFS_OWN_SORT
  25 #include "yaffs_qsort.h"
  26 #endif
  27 #include "yaffs_nand.h"
  28
  29 #include "yaffs_checkptrw.h"
  30
  31 #include "yaffs_nand.h"
  32 #include "yaffs_packedtags2.h"
  33
  34
  35 #ifdef CONFIG_YAFFS_WINCE
  36 void yfsd_LockYAFFS(BOOL fsLockOnly);
  37 void yfsd_UnlockYAFFS(BOOL fsLockOnly);
  38 #endif
  39
  40 #define YAFFS_PASSIVE_GC_CHUNKS 2
  41
  42 #include "yaffs_ecc.h"
  43
  44
  45 /* Robustification (if it ever comes about...) */
  46 static void yaffs_RetireBlock(yaffs_Device * dev, int blockInNAND);
  47 static void yaffs_HandleWriteChunkError(yaffs_Device * dev, int chunkInNAND, int erasedOk);
  48 static void yaffs_HandleWriteChunkOk(yaffs_Device * dev, int chunkInNAND,
  49                                      const __u8 * data,
  50                                      const yaffs_ExtendedTags * tags);
  51 static void yaffs_HandleUpdateChunk(yaffs_Device * dev, int chunkInNAND,
  52                                     const yaffs_ExtendedTags * tags);
  53
  54 /* Other local prototypes */
  55 static int yaffs_UnlinkObject( yaffs_Object *obj);
  56 static int yaffs_ObjectHasCachedWriteData(yaffs_Object *obj);
  57
  58 static void yaffs_HardlinkFixup(yaffs_Device *dev, yaffs_Object *hardList);
  59
  60 static int yaffs_WriteNewChunkWithTagsToNAND(yaffs_Device * dev,
  61                                              const __u8 * buffer,
  62                                              yaffs_ExtendedTags * tags,
  63                                              int useReserve);
  64 static int yaffs_PutChunkIntoFile(yaffs_Object * in, int chunkInInode,
  65                                   int chunkInNAND, int inScan);
  66
  67 static yaffs_Object *yaffs_CreateNewObject(yaffs_Device * dev, int number,
  68                                            yaffs_ObjectType type);
  69 static void yaffs_AddObjectToDirectory(yaffs_Object * directory,
  70                                        yaffs_Object * obj);
  71 static int yaffs_UpdateObjectHeader(yaffs_Object * in, const YCHAR * name,
  72                                     int force, int isShrink, int shadows);
  73 static void yaffs_RemoveObjectFromDirectory(yaffs_Object * obj);
  74 static int yaffs_CheckStructures(void);
  75 static int yaffs_DeleteWorker(yaffs_Object * in, yaffs_Tnode * tn, __u32 level,
  76                               int chunkOffset, int *limit);
  77 static int yaffs_DoGenericObjectDeletion(yaffs_Object * in);
  78
  79 static yaffs_BlockInfo *yaffs_GetBlockInfo(yaffs_Device * dev, int blockNo);
  80
  81 static __u8 *yaffs_GetTempBuffer(yaffs_Device * dev, int lineNo);
  82 static void yaffs_ReleaseTempBuffer(yaffs_Device * dev, __u8 * buffer,
  83                                     int lineNo);
  84
  85 static int yaffs_CheckChunkErased(struct yaffs_DeviceStruct *dev,
  86                                   int chunkInNAND);
  87
  88 static int yaffs_UnlinkWorker(yaffs_Object * obj);
  89 static void yaffs_DestroyObject(yaffs_Object * obj);
  90
  91 static int yaffs_TagsMatch(const yaffs_ExtendedTags * tags, int objectId,
  92                            int chunkInObject);
  93
  94 loff_t yaffs_GetFileSize(yaffs_Object * obj);
  95
  96 static int yaffs_AllocateChunk(yaffs_Device * dev, int useReserve, yaffs_BlockInfo **blockUsedPtr);
  97
  98 static void yaffs_VerifyFreeChunks(yaffs_Device * dev);
  99
 100 #ifdef YAFFS_PARANOID
 101 static int yaffs_CheckFileSanity(yaffs_Object * in);
 102 #else
 103 #define yaffs_CheckFileSanity(in)
 104 #endif
 105
 106 static void yaffs_InvalidateWholeChunkCache(yaffs_Object * in);
 107 static void yaffs_InvalidateChunkCache(yaffs_Object * object, int chunkId);
 108
 109 static void yaffs_InvalidateCheckpoint(yaffs_Device *dev);
 110
 111
 112
 113 /* Function to calculate chunk and offset */
 114
 115 static void yaffs_AddrToChunk(yaffs_Device *dev, loff_t addr, __u32 *chunk, __u32 *offset)
 116 {
 117         if(dev->chunkShift){
 118                 /* Easy-peasy power of 2 case */
 119                 *chunk  = (__u32)(addr >> dev->chunkShift);
 120                 *offset = (__u32)(addr & dev->chunkMask);
 121         }
 122         else if(dev->crumbsPerChunk)
 123         {
 124                 /* Case where we're using "crumbs" */
 125                 *offset = (__u32)(addr & dev->crumbMask);
 126                 addr >>= dev->crumbShift;
 127                 *chunk = ((__u32)addr)/dev->crumbsPerChunk;
 128                 *offset += ((addr - (*chunk * dev->crumbsPerChunk)) << dev->crumbShift);
 129         }
 130         else
 131                 YBUG();
 132 }
 133
 134 /* Function to return the number of shifts for a power of 2 greater than or equal
 135  * to the given number
 136  * Note we don't try to cater for all possible numbers and this does not have to
 137  * be hellishly efficient.
 138  */
 139
 140 static __u32 ShiftsGE(__u32 x)
 141 {
 142         int extraBits;
 143         int nShifts;
 144
 145         nShifts = extraBits = 0;
 146
 147         while(x>1){
 148                 if(x & 1) extraBits++;
 149                 x>>=1;
 150                 nShifts++;
 151         }
 152
 153         if(extraBits)
 154                 nShifts++;
 155
 156         return nShifts;
 157 }
 158
 159 /* Function to return the number of shifts to get a 1 in bit 0
 160  */
 161
 162 static __u32 ShiftDiv(__u32 x)
 163 {
 164         int nShifts;
 165
 166         nShifts =  0;
 167
 168         if(!x) return 0;
 169
 170         while( !(x&1)){
 171                 x>>=1;
 172                 nShifts++;
 173         }
 174
 175         return nShifts;
 176 }
 177
 178
 179
 180 /*
 181  * Temporary buffer manipulations.
 182  */
 183
 184 static __u8 *yaffs_GetTempBuffer(yaffs_Device * dev, int lineNo)
 185 {
 186         int i, j;
 187         for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
 188                 if (dev->tempBuffer[i].line == 0) {
 189                         dev->tempBuffer[i].line = lineNo;
 190                         if ((i + 1) > dev->maxTemp) {
 191                                 dev->maxTemp = i + 1;
 192                                 for (j = 0; j <= i; j++)
 193                                         dev->tempBuffer[j].maxLine =
 194                                             dev->tempBuffer[j].line;
 195                         }
 196
 197                         return dev->tempBuffer[i].buffer;
 198                 }
 199         }
 200
 201         T(YAFFS_TRACE_BUFFERS,
 202           (TSTR("Out of temp buffers at line %d, other held by lines:"),
 203            lineNo));
 204         for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
 205                 T(YAFFS_TRACE_BUFFERS, (TSTR(" %d "), dev->tempBuffer[i].line));
 206         }
 207         T(YAFFS_TRACE_BUFFERS, (TSTR(" " TENDSTR)));
 208
 209         /*
 210          * If we got here then we have to allocate an unmanaged one
 211          * This is not good.
 212          */
 213
 214         dev->unmanagedTempAllocations++;
 215         return YMALLOC(dev->nDataBytesPerChunk);
 216
 217 }
 218
 219 static void yaffs_ReleaseTempBuffer(yaffs_Device * dev, __u8 * buffer,
 220                                     int lineNo)
 221 {
 222         int i;
 223         for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
 224                 if (dev->tempBuffer[i].buffer == buffer) {
 225                         dev->tempBuffer[i].line = 0;
 226                         return;
 227                 }
 228         }
 229
 230         if (buffer) {
 231                 /* assume it is an unmanaged one. */
 232                 T(YAFFS_TRACE_BUFFERS,
 233                   (TSTR("Releasing unmanaged temp buffer in line %d" TENDSTR),
 234                    lineNo));
 235                 YFREE(buffer);
 236                 dev->unmanagedTempDeallocations++;
 237         }
 238
 239 }
 240
 241 /*
 242  * Determine if we have a managed buffer.
 243  */
 244 int yaffs_IsManagedTempBuffer(yaffs_Device * dev, const __u8 * buffer)
 245 {
 246         int i;
 247         for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
 248                 if (dev->tempBuffer[i].buffer == buffer)
 249                         return 1;
 250
 251         }
 252
 253     for (i = 0; i < dev->nShortOpCaches; i++) {
 254         if( dev->srCache[i].data == buffer )
 255             return 1;
 256
 257     }
 258
 259     if (buffer == dev->checkpointBuffer)
 260       return 1;
 261
 262     T(YAFFS_TRACE_ALWAYS,
 263           (TSTR("yaffs: unmaged buffer detected.\n" TENDSTR)));
 264     return 0;
 265 }
 266
 267 /*
 268  * Chunk bitmap manipulations
 269  */
 270
 271 static Y_INLINE __u8 *yaffs_BlockBits(yaffs_Device * dev, int blk)
 272 {
 273         if (blk < dev->internalStartBlock || blk > dev->internalEndBlock) {
 274                 T(YAFFS_TRACE_ERROR,
 275                   (TSTR("**>> yaffs: BlockBits block %d is not valid" TENDSTR),
 276                    blk));
 277                 YBUG();
 278         }
 279         return dev->chunkBits +
 280             (dev->chunkBitmapStride * (blk - dev->internalStartBlock));
 281 }
 282
 283 static Y_INLINE void yaffs_ClearChunkBits(yaffs_Device * dev, int blk)
 284 {
 285         __u8 *blkBits = yaffs_BlockBits(dev, blk);
 286
 287         memset(blkBits, 0, dev->chunkBitmapStride);
 288 }
 289
 290 static Y_INLINE void yaffs_ClearChunkBit(yaffs_Device * dev, int blk, int chunk)
 291 {
 292         __u8 *blkBits = yaffs_BlockBits(dev, blk);
 293
 294         blkBits[chunk / 8] &= ~(1 << (chunk & 7));
 295 }
 296
 297 static Y_INLINE void yaffs_SetChunkBit(yaffs_Device * dev, int blk, int chunk)
 298 {
 299         __u8 *blkBits = yaffs_BlockBits(dev, blk);
 300
 301         blkBits[chunk / 8] |= (1 << (chunk & 7));
 302 }
 303
 304 static Y_INLINE int yaffs_CheckChunkBit(yaffs_Device * dev, int blk, int chunk)
 305 {
 306         __u8 *blkBits = yaffs_BlockBits(dev, blk);
 307         return (blkBits[chunk / 8] & (1 << (chunk & 7))) ? 1 : 0;
 308 }
 309
 310 static Y_INLINE int yaffs_StillSomeChunkBits(yaffs_Device * dev, int blk)
 311 {
 312         __u8 *blkBits = yaffs_BlockBits(dev, blk);
 313         int i;
 314         for (i = 0; i < dev->chunkBitmapStride; i++) {
 315                 if (*blkBits)
 316                         return 1;
 317                 blkBits++;
 318         }
 319         return 0;
 320 }
 321
 322 /*
 323  *  Simple hash function. Needs to have a reasonable spread
 324  */
 325
 326 static Y_INLINE int yaffs_HashFunction(int n)
 327 {
 328         n = abs(n);
 329         return (n % YAFFS_NOBJECT_BUCKETS);
 330 }
 331
 332 /*
 333  * Access functions to useful fake objects
 334  */
 335
 336 yaffs_Object *yaffs_Root(yaffs_Device * dev)
 337 {
 338         return dev->rootDir;
 339 }
 340
 341 yaffs_Object *yaffs_LostNFound(yaffs_Device * dev)
 342 {
 343         return dev->lostNFoundDir;
 344 }
 345
 346
 347 /*
 348  *  Erased NAND checking functions
 349  */
 350
 351 int yaffs_CheckFF(__u8 * buffer, int nBytes)
 352 {
 353         /* Horrible, slow implementation */
 354         while (nBytes--) {
 355                 if (*buffer != 0xFF)
 356                         return 0;
 357                 buffer++;
 358         }
 359         return 1;
 360 }
 361
 362 static int yaffs_CheckChunkErased(struct yaffs_DeviceStruct *dev,
 363                                   int chunkInNAND)
 364 {
 365
 366         int retval = YAFFS_OK;
 367         __u8 *data = yaffs_GetTempBuffer(dev, __LINE__);
 368         yaffs_ExtendedTags tags;
 369         int result;
 370
 371         result = yaffs_ReadChunkWithTagsFromNAND(dev, chunkInNAND, data, &tags);
 372
 373         if(tags.eccResult > YAFFS_ECC_RESULT_NO_ERROR)
 374                 retval = YAFFS_FAIL;
 375
 376
 377         if (!yaffs_CheckFF(data, dev->nDataBytesPerChunk) || tags.chunkUsed) {
 378                 T(YAFFS_TRACE_NANDACCESS,
 379                   (TSTR("Chunk %d not erased" TENDSTR), chunkInNAND));
 380                 retval = YAFFS_FAIL;
 381         }
 382
 383         yaffs_ReleaseTempBuffer(dev, data, __LINE__);
 384
 385         return retval;
 386
 387 }
 388
 389 static int yaffs_WriteNewChunkWithTagsToNAND(struct yaffs_DeviceStruct *dev,
 390                                              const __u8 * data,
 391                                              yaffs_ExtendedTags * tags,
 392                                              int useReserve)
 393 {
 394         int chunk;
 395
 396         int writeOk = 0;
 397         int erasedOk = 1;
 398         int attempts = 0;
 399         yaffs_BlockInfo *bi;
 400
 401         yaffs_InvalidateCheckpoint(dev);
 402
 403         do {
 404                 chunk = yaffs_AllocateChunk(dev, useReserve,&bi);
 405
 406                 if (chunk >= 0) {
 407                         /* First check this chunk is erased, if it needs checking.
 408                          * The checking policy (unless forced always on) is as follows:
 409                          * Check the first page we try to write in a block.
 410                          * - If the check passes then we don't need to check any more.
 411                          * - If the check fails, we check again...
 412                          * If the block has been erased, we don't need to check.
 413                          *
 414                          * However, if the block has been prioritised for gc, then
 415                          * we think there might be something odd about this block
 416                          * and stop using it.
 417                          *
 418                          * Rationale:
 419                          * We should only ever see chunks that have not been erased
 420                          * if there was a partially written chunk due to power loss
 421                          * This checking policy should catch that case with very
 422                          * few checks and thus save a lot of checks that are most likely not
 423                          * needed.
 424                          */
 425
 426                          if(bi->gcPrioritise){
 427                                         yaffs_DeleteChunk(dev, chunk, 1, __LINE__);
 428                         } else {
 429 #ifdef CONFIG_YAFFS_ALWAYS_CHECK_CHUNK_ERASED
 430
 431                                 bi->skipErasedCheck = 0;
 432
 433 #endif
 434                                 if(!bi->skipErasedCheck){
 435                                         erasedOk = yaffs_CheckChunkErased(dev, chunk);
 436                                         if(erasedOk && !bi->gcPrioritise)
 437                                                 bi->skipErasedCheck = 1;
 438                                 }
 439
 440                                 if (!erasedOk) {
 441                                         T(YAFFS_TRACE_ERROR,
 442                                           (TSTR
 443                                            ("**>> yaffs chunk %d was not erased"
 444                                             TENDSTR), chunk));
 445                                 } else {
 446                                         writeOk =
 447                                             yaffs_WriteChunkWithTagsToNAND(dev, chunk,
 448                                                                            data, tags);
 449                                 }
 450
 451                                 attempts++;
 452
 453                                 if (writeOk) {
 454                                         /*
 455                                          *  Copy the data into the robustification buffer.
 456                                          *  NB We do this at the end to prevent duplicates in the case of a write error.
 457                                          *  Todo
 458                                          */
 459                                         yaffs_HandleWriteChunkOk(dev, chunk, data, tags);
 460
 461                                 } else {
 462                                         /* The erased check or write failed */
 463                                         yaffs_HandleWriteChunkError(dev, chunk, erasedOk);
 464                                 }
 465                         }
 466                 }
 467
 468         } while (chunk >= 0 && !writeOk);
 469
 470         if (attempts > 1) {
 471                 T(YAFFS_TRACE_ERROR,
 472                   (TSTR("**>> yaffs write required %d attempts" TENDSTR),
 473                    attempts));
 474                 dev->nRetriedWrites += (attempts - 1);
 475         }
 476
 477         return chunk;
 478 }
 479
 480 /*
 481  * Block retiring for handling a broken block.
 482  */
 483
 484 static void yaffs_RetireBlock(yaffs_Device * dev, int blockInNAND)
 485 {
 486         yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, blockInNAND);
 487
 488         yaffs_InvalidateCheckpoint(dev);
 489
 490         yaffs_MarkBlockBad(dev, blockInNAND);
 491
 492         bi->blockState = YAFFS_BLOCK_STATE_DEAD;
 493         bi->gcPrioritise = 0;
 494         bi->needsRetiring = 0;
 495
 496         dev->nRetiredBlocks++;
 497 }
 498
 499 /*
 500  * Functions for robustisizing TODO
 501  *
 502  */
 503
 504 static void yaffs_HandleWriteChunkOk(yaffs_Device * dev, int chunkInNAND,
 505                                      const __u8 * data,
 506                                      const yaffs_ExtendedTags * tags)
 507 {
 508 }
 509
 510 static void yaffs_HandleUpdateChunk(yaffs_Device * dev, int chunkInNAND,
 511                                     const yaffs_ExtendedTags * tags)
 512 {
 513 }
 514
 515 void yaffs_HandleChunkError(yaffs_Device *dev, yaffs_BlockInfo *bi)
 516 {
 517         if(!bi->gcPrioritise){
 518                 bi->gcPrioritise = 1;
 519                 dev->hasPendingPrioritisedGCs = 1;
 520                 bi->chunkErrorStrikes ++;
 521
 522                 if(bi->chunkErrorStrikes > 3){
 523                         bi->needsRetiring = 1; /* Too many stikes, so retire this */
 524                         T(YAFFS_TRACE_ALWAYS, (TSTR("yaffs: Block struck out" TENDSTR)));
 525
 526                 }
 527
 528         }
 529 }
 530
 531 static void yaffs_ReportOddballBlocks(yaffs_Device *dev)
 532 {
 533         int i;
 534
 535         for(i = dev->internalStartBlock; i <= dev->internalEndBlock && (yaffs_traceMask & YAFFS_TRACE_BAD_BLOCKS); i++){
 536                 yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev,i);
 537                 if(bi->needsRetiring || bi->gcPrioritise)
 538                         T(YAFFS_TRACE_BAD_BLOCKS,(TSTR("yaffs block %d%s%s" TENDSTR),
 539                                 i,
 540                                 bi->needsRetiring ? " needs retiring" : "",
 541                                 bi->gcPrioritise ?  " gc prioritised" : ""));
 542
 543         }
 544 }
 545
 546 static void yaffs_HandleWriteChunkError(yaffs_Device * dev, int chunkInNAND, int erasedOk)
 547 {
 548
 549         int blockInNAND = chunkInNAND / dev->nChunksPerBlock;
 550         yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, blockInNAND);
 551
 552         yaffs_HandleChunkError(dev,bi);
 553
 554
 555         if(erasedOk ) {
 556                 /* Was an actual write failure, so mark the block for retirement  */
 557                 bi->needsRetiring = 1;
 558                 T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
 559                   (TSTR("**>> Block %d needs retiring" TENDSTR), blockInNAND));
 560
 561
 562         }
 563
 564         /* Delete the chunk */
 565         yaffs_DeleteChunk(dev, chunkInNAND, 1, __LINE__);
 566 }
 567
 568
 569 /*---------------- Name handling functions ------------*/
 570
 571 static __u16 yaffs_CalcNameSum(const YCHAR * name)
 572 {
 573         __u16 sum = 0;
 574         __u16 i = 1;
 575
 576         YUCHAR *bname = (YUCHAR *) name;
 577         if (bname) {
 578                 while ((*bname) && (i <= YAFFS_MAX_NAME_LENGTH)) {
 579
 580 #ifdef CONFIG_YAFFS_CASE_INSENSITIVE
 581                         sum += yaffs_toupper(*bname) * i;
 582 #else
 583                         sum += (*bname) * i;
 584 #endif
 585                         i++;
 586                         bname++;
 587                 }
 588         }
 589         return sum;
 590 }
 591
 592 static void yaffs_SetObjectName(yaffs_Object * obj, const YCHAR * name)
 593 {
 594 #ifdef CONFIG_YAFFS_SHORT_NAMES_IN_RAM
 595         if (name && yaffs_strlen(name) <= YAFFS_SHORT_NAME_LENGTH) {
 596                 yaffs_strcpy(obj->shortName, name);
 597         } else {
 598                 obj->shortName[0] = _Y('\0');
 599         }
 600 #endif
 601         obj->sum = yaffs_CalcNameSum(name);
 602 }
 603
 604 /*-------------------- TNODES -------------------
 605
 606  * List of spare tnodes
 607  * The list is hooked together using the first pointer
 608  * in the tnode.
 609  */
 610
 611 /* yaffs_CreateTnodes creates a bunch more tnodes and
 612  * adds them to the tnode free list.
 613  * Don't use this function directly
 614  */
 615
 616 static int yaffs_CreateTnodes(yaffs_Device * dev, int nTnodes)
 617 {
 618         int i;
 619         int tnodeSize;
 620         yaffs_Tnode *newTnodes;
 621         __u8 *mem;
 622         yaffs_Tnode *curr;
 623         yaffs_Tnode *next;
 624         yaffs_TnodeList *tnl;
 625
 626         if (nTnodes < 1)
 627                 return YAFFS_OK;
 628
 629         /* Calculate the tnode size in bytes for variable width tnode support.
 630          * Must be a multiple of 32-bits  */
 631         tnodeSize = (dev->tnodeWidth * YAFFS_NTNODES_LEVEL0)/8;
 632
 633         /* make these things */
 634
 635         newTnodes = YMALLOC(nTnodes * tnodeSize);
 636         mem = (__u8 *)newTnodes;
 637
 638         if (!newTnodes) {
 639                 T(YAFFS_TRACE_ERROR,
 640                   (TSTR("yaffs: Could not allocate Tnodes" TENDSTR)));
 641                 return YAFFS_FAIL;
 642         }
 643
 644         /* Hook them into the free list */
 645 #if 0
 646         for (i = 0; i < nTnodes - 1; i++) {
 647                 newTnodes[i].internal[0] = &newTnodes[i + 1];
 648 #ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
 649                 newTnodes[i].internal[YAFFS_NTNODES_INTERNAL] = (void *)1;
 650 #endif
 651         }
 652
 653         newTnodes[nTnodes - 1].internal[0] = dev->freeTnodes;
 654 #ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
 655         newTnodes[nTnodes - 1].internal[YAFFS_NTNODES_INTERNAL] = (void *)1;
 656 #endif
 657         dev->freeTnodes = newTnodes;
 658 #else
 659         /* New hookup for wide tnodes */
 660         for(i = 0; i < nTnodes -1; i++) {
 661                 curr = (yaffs_Tnode *) &mem[i * tnodeSize];
 662                 next = (yaffs_Tnode *) &mem[(i+1) * tnodeSize];
 663                 curr->internal[0] = next;
 664         }
 665
 666         curr = (yaffs_Tnode *) &mem[(nTnodes - 1) * tnodeSize];
 667         curr->internal[0] = dev->freeTnodes;
 668         dev->freeTnodes = (yaffs_Tnode *)mem;
 669
 670 #endif
 671
 672
 673         dev->nFreeTnodes += nTnodes;
 674         dev->nTnodesCreated += nTnodes;
 675
 676         /* Now add this bunch of tnodes to a list for freeing up.
 677          * NB If we can't add this to the management list it isn't fatal
 678          * but it just means we can't free this bunch of tnodes later.
 679          */
 680
 681         tnl = YMALLOC(sizeof(yaffs_TnodeList));
 682         if (!tnl) {
 683                 T(YAFFS_TRACE_ERROR,
 684                   (TSTR
 685                    ("yaffs: Could not add tnodes to management list" TENDSTR)));
 686
 687         } else {
 688                 tnl->tnodes = newTnodes;
 689                 tnl->next = dev->allocatedTnodeList;
 690                 dev->allocatedTnodeList = tnl;
 691         }
 692
 693         T(YAFFS_TRACE_ALLOCATE, (TSTR("yaffs: Tnodes added" TENDSTR)));
 694
 695         return YAFFS_OK;
 696 }
 697
 698 /* GetTnode gets us a clean tnode. Tries to make allocate more if we run out */
 699
 700 static yaffs_Tnode *yaffs_GetTnodeRaw(yaffs_Device * dev)
 701 {
 702         yaffs_Tnode *tn = NULL;
 703
 704         /* If there are none left make more */
 705         if (!dev->freeTnodes) {
 706                 yaffs_CreateTnodes(dev, YAFFS_ALLOCATION_NTNODES);
 707         }
 708
 709         if (dev->freeTnodes) {
 710                 tn = dev->freeTnodes;
 711 #ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
 712                 if (tn->internal[YAFFS_NTNODES_INTERNAL] != (void *)1) {
 713                         /* Hoosterman, this thing looks like it isn't in the list */
 714                         T(YAFFS_TRACE_ALWAYS,
 715                           (TSTR("yaffs: Tnode list bug 1" TENDSTR)));
 716                 }
 717 #endif
 718                 dev->freeTnodes = dev->freeTnodes->internal[0];
 719                 dev->nFreeTnodes--;
 720         }
 721
 722         return tn;
 723 }
 724
 725 static yaffs_Tnode *yaffs_GetTnode(yaffs_Device * dev)
 726 {
 727         yaffs_Tnode *tn = yaffs_GetTnodeRaw(dev);
 728
 729         if(tn)
 730                 memset(tn, 0, (dev->tnodeWidth * YAFFS_NTNODES_LEVEL0)/8);
 731
 732         return tn;
 733 }
 734
 735 /* FreeTnode frees up a tnode and puts it back on the free list */
 736 static void yaffs_FreeTnode(yaffs_Device * dev, yaffs_Tnode * tn)
 737 {
 738         if (tn) {
 739 #ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
 740                 if (tn->internal[YAFFS_NTNODES_INTERNAL] != 0) {
 741                         /* Hoosterman, this thing looks like it is already in the list */
 742                         T(YAFFS_TRACE_ALWAYS,
 743                           (TSTR("yaffs: Tnode list bug 2" TENDSTR)));
 744                 }
 745                 tn->internal[YAFFS_NTNODES_INTERNAL] = (void *)1;
 746 #endif
 747                 tn->internal[0] = dev->freeTnodes;
 748                 dev->freeTnodes = tn;
 749                 dev->nFreeTnodes++;
 750         }
 751 }
 752
 753 static void yaffs_DeinitialiseTnodes(yaffs_Device * dev)
 754 {
 755         /* Free the list of allocated tnodes */
 756         yaffs_TnodeList *tmp;
 757
 758         while (dev->allocatedTnodeList) {
 759                 tmp = dev->allocatedTnodeList->next;
 760
 761                 YFREE(dev->allocatedTnodeList->tnodes);
 762                 YFREE(dev->allocatedTnodeList);
 763                 dev->allocatedTnodeList = tmp;
 764
 765         }
 766
 767         dev->freeTnodes = NULL;
 768         dev->nFreeTnodes = 0;
 769 }
 770
 771 static void yaffs_InitialiseTnodes(yaffs_Device * dev)
 772 {
 773         dev->allocatedTnodeList = NULL;
 774         dev->freeTnodes = NULL;
 775         dev->nFreeTnodes = 0;
 776         dev->nTnodesCreated = 0;
 777
 778 }
 779
 780
 781 void yaffs_PutLevel0Tnode(yaffs_Device *dev, yaffs_Tnode *tn, unsigned pos, unsigned val)
 782 {
 783   __u32 *map = (__u32 *)tn;
 784   __u32 bitInMap;
 785   __u32 bitInWord;
 786   __u32 wordInMap;
 787   __u32 mask;
 788
 789   pos &= YAFFS_TNODES_LEVEL0_MASK;
 790   val >>= dev->chunkGroupBits;
 791
 792   bitInMap = pos * dev->tnodeWidth;
 793   wordInMap = bitInMap /32;
 794   bitInWord = bitInMap & (32 -1);
 795
 796   mask = dev->tnodeMask << bitInWord;
 797
 798   map[wordInMap] &= ~mask;
 799   map[wordInMap] |= (mask & (val << bitInWord));
 800
 801   if(dev->tnodeWidth > (32-bitInWord)) {
 802     bitInWord = (32 - bitInWord);
 803     wordInMap++;;
 804     mask = dev->tnodeMask >> (/*dev->tnodeWidth -*/ bitInWord);
 805     map[wordInMap] &= ~mask;
 806     map[wordInMap] |= (mask & (val >> bitInWord));
 807   }
 808 }
 809
 810 __u32 yaffs_GetChunkGroupBase(yaffs_Device *dev, yaffs_Tnode *tn, unsigned pos)
 811 {
 812   __u32 *map = (__u32 *)tn;
 813   __u32 bitInMap;
 814   __u32 bitInWord;
 815   __u32 wordInMap;
 816   __u32 val;
 817
 818   pos &= YAFFS_TNODES_LEVEL0_MASK;
 819
 820   bitInMap = pos * dev->tnodeWidth;
 821   wordInMap = bitInMap /32;
 822   bitInWord = bitInMap & (32 -1);
 823
 824   val = map[wordInMap] >> bitInWord;
 825
 826   if(dev->tnodeWidth > (32-bitInWord)) {
 827     bitInWord = (32 - bitInWord);
 828     wordInMap++;;
 829     val |= (map[wordInMap] << bitInWord);
 830   }
 831
 832   val &= dev->tnodeMask;
 833   val <<= dev->chunkGroupBits;
 834
 835   return val;
 836 }
 837
 838 /* ------------------- End of individual tnode manipulation -----------------*/
 839
 840 /* ---------Functions to manipulate the look-up tree (made up of tnodes) ------
 841  * The look up tree is represented by the top tnode and the number of topLevel
 842  * in the tree. 0 means only the level 0 tnode is in the tree.
 843  */
 844
 845 /* FindLevel0Tnode finds the level 0 tnode, if one exists. */
 846 static yaffs_Tnode *yaffs_FindLevel0Tnode(yaffs_Device * dev,
 847                                           yaffs_FileStructure * fStruct,
 848                                           __u32 chunkId)
 849 {
 850
 851         yaffs_Tnode *tn = fStruct->top;
 852         __u32 i;
 853         int requiredTallness;
 854         int level = fStruct->topLevel;
 855
 856         /* Check sane level and chunk Id */
 857         if (level < 0 || level > YAFFS_TNODES_MAX_LEVEL) {
 858                 return NULL;
 859         }
 860
 861         if (chunkId > YAFFS_MAX_CHUNK_ID) {
 862                 return NULL;
 863         }
 864
 865         /* First check we're tall enough (ie enough topLevel) */
 866
 867         i = chunkId >> YAFFS_TNODES_LEVEL0_BITS;
 868         requiredTallness = 0;
 869         while (i) {
 870                 i >>= YAFFS_TNODES_INTERNAL_BITS;
 871                 requiredTallness++;
 872         }
 873
 874         if (requiredTallness > fStruct->topLevel) {
 875                 /* Not tall enough, so we can't find it, return NULL. */
 876                 return NULL;
 877         }
 878
 879         /* Traverse down to level 0 */
 880         while (level > 0 && tn) {
 881                 tn = tn->
 882                     internal[(chunkId >>
 883                                ( YAFFS_TNODES_LEVEL0_BITS +
 884                                  (level - 1) *
 885                                  YAFFS_TNODES_INTERNAL_BITS)
 886                               ) &
 887                              YAFFS_TNODES_INTERNAL_MASK];
 888                 level--;
 889
 890         }
 891
 892         return tn;
 893 }
 894
 895 /* AddOrFindLevel0Tnode finds the level 0 tnode if it exists, otherwise first expands the tree.
 896  * This happens in two steps:
 897  *  1. If the tree isn't tall enough, then make it taller.
 898  *  2. Scan down the tree towards the level 0 tnode adding tnodes if required.
 899  *
 900  * Used when modifying the tree.
 901  *
 902  *  If the tn argument is NULL, then a fresh tnode will be added otherwise the specified tn will
 903  *  be plugged into the ttree.
 904  */
 905
 906 static yaffs_Tnode *yaffs_AddOrFindLevel0Tnode(yaffs_Device * dev,
 907                                                yaffs_FileStructure * fStruct,
 908                                                __u32 chunkId,
 909                                                yaffs_Tnode *passedTn)
 910 {
 911
 912         int requiredTallness;
 913         int i;
 914         int l;
 915         yaffs_Tnode *tn;
 916
 917         __u32 x;
 918
 919
 920         /* Check sane level and page Id */
 921         if (fStruct->topLevel < 0 || fStruct->topLevel > YAFFS_TNODES_MAX_LEVEL) {
 922                 return NULL;
 923         }
 924
 925         if (chunkId > YAFFS_MAX_CHUNK_ID) {
 926                 return NULL;
 927         }
 928
 929         /* First check we're tall enough (ie enough topLevel) */
 930
 931         x = chunkId >> YAFFS_TNODES_LEVEL0_BITS;
 932         requiredTallness = 0;
 933         while (x) {
 934                 x >>= YAFFS_TNODES_INTERNAL_BITS;
 935                 requiredTallness++;
 936         }
 937
 938
 939         if (requiredTallness > fStruct->topLevel) {
 940                 /* Not tall enough,gotta make the tree taller */
 941                 for (i = fStruct->topLevel; i < requiredTallness; i++) {
 942
 943                         tn = yaffs_GetTnode(dev);
 944
 945                         if (tn) {
 946                                 tn->internal[0] = fStruct->top;
 947                                 fStruct->top = tn;
 948                         } else {
 949                                 T(YAFFS_TRACE_ERROR,
 950                                   (TSTR("yaffs: no more tnodes" TENDSTR)));
 951                         }
 952                 }
 953
 954                 fStruct->topLevel = requiredTallness;
 955         }
 956
 957         /* Traverse down to level 0, adding anything we need */
 958
 959         l = fStruct->topLevel;
 960         tn = fStruct->top;
 961
 962         if(l > 0) {
 963                 while (l > 0 && tn) {
 964                         x = (chunkId >>
 965                              ( YAFFS_TNODES_LEVEL0_BITS +
 966                               (l - 1) * YAFFS_TNODES_INTERNAL_BITS)) &
 967                             YAFFS_TNODES_INTERNAL_MASK;
 968
 969
 970                         if((l>1) && !tn->internal[x]){
 971                                 /* Add missing non-level-zero tnode */
 972                                 tn->internal[x] = yaffs_GetTnode(dev);
 973
 974                         } else if(l == 1) {
 975                                 /* Looking from level 1 at level 0 */
 976                                 if (passedTn) {
 977                                         /* If we already have one, then release it.*/
 978                                         if(tn->internal[x])
 979                                                 yaffs_FreeTnode(dev,tn->internal[x]);
 980                                         tn->internal[x] = passedTn;
 981
 982                                 } else if(!tn->internal[x]) {
 983                                         /* Don't have one, none passed in */
 984                                         tn->internal[x] = yaffs_GetTnode(dev);
 985                                 }
 986                         }
 987
 988                         tn = tn->internal[x];
 989                         l--;
 990                 }
 991         } else {
 992                 /* top is level 0 */
 993                 if(passedTn) {
 994                         memcpy(tn,passedTn,(dev->tnodeWidth * YAFFS_NTNODES_LEVEL0)/8);
 995                         yaffs_FreeTnode(dev,passedTn);
 996                 }
 997         }
 998
 999         return tn;
1000 }
1001
1002 static int yaffs_FindChunkInGroup(yaffs_Device * dev, int theChunk,
1003                                   yaffs_ExtendedTags * tags, int objectId,
1004                                   int chunkInInode)
1005 {
1006         int j;
1007
1008         for (j = 0; theChunk && j < dev->chunkGroupSize; j++) {
1009                 if (yaffs_CheckChunkBit
1010                     (dev, theChunk / dev->nChunksPerBlock,
1011                      theChunk % dev->nChunksPerBlock)) {
1012                         yaffs_ReadChunkWithTagsFromNAND(dev, theChunk, NULL,
1013                                                         tags);
1014                         if (yaffs_TagsMatch(tags, objectId, chunkInInode)) {
1015                                 /* found it; */
1016                                 return theChunk;
1017
1018                         }
1019                 }
1020                 theChunk++;
1021         }
1022         return -1;
1023 }
1024
1025
1026 /* DeleteWorker scans backwards through the tnode tree and deletes all the
1027  * chunks and tnodes in the file
1028  * Returns 1 if the tree was deleted.
1029  * Returns 0 if it stopped early due to hitting the limit and the delete is incomplete.
1030  */
1031
1032 static int yaffs_DeleteWorker(yaffs_Object * in, yaffs_Tnode * tn, __u32 level,
1033                               int chunkOffset, int *limit)
1034 {
1035         int i;
1036         int chunkInInode;
1037         int theChunk;
1038         yaffs_ExtendedTags tags;
1039         int foundChunk;
1040         yaffs_Device *dev = in->myDev;
1041
1042         int allDone = 1;
1043
1044         if (tn) {
1045                 if (level > 0) {
1046
1047                         for (i = YAFFS_NTNODES_INTERNAL - 1; allDone && i >= 0;
1048                              i--) {
1049                                 if (tn->internal[i]) {
1050                                         if (limit && (*limit) < 0) {
1051                                                 allDone = 0;
1052                                         } else {
1053                                                 allDone =
1054                                                     yaffs_DeleteWorker(in,
1055                                                                        tn->
1056                                                                        internal
1057                                                                        [i],
1058                                                                        level -
1059                                                                        1,
1060                                                                        (chunkOffset
1061                                                                         <<
1062                                                                         YAFFS_TNODES_INTERNAL_BITS)
1063                                                                        + i,
1064                                                                        limit);
1065                                         }
1066                                         if (allDone) {
1067                                                 yaffs_FreeTnode(dev,
1068                                                                 tn->
1069                                                                 internal[i]);
1070                                                 tn->internal[i] = NULL;
1071                                         }
1072                                 }
1073
1074                         }
1075                         return (allDone) ? 1 : 0;
1076                 } else if (level == 0) {
1077                         int hitLimit = 0;
1078
1079                         for (i = YAFFS_NTNODES_LEVEL0 - 1; i >= 0 && !hitLimit;
1080                              i--) {
1081                                 theChunk = yaffs_GetChunkGroupBase(dev,tn,i);
1082                                 if (theChunk) {
1083
1084                                         chunkInInode =
1085                                             (chunkOffset <<
1086                                              YAFFS_TNODES_LEVEL0_BITS) + i;
1087
1088                                         foundChunk =
1089                                             yaffs_FindChunkInGroup(dev,
1090                                                                    theChunk,
1091                                                                    &tags,
1092                                                                    in->objectId,
1093                                                                    chunkInInode);
1094
1095                                         if (foundChunk > 0) {
1096                                                 yaffs_DeleteChunk(dev,
1097                                                                   foundChunk, 1,
1098                                                                   __LINE__);
1099                                                 in->nDataChunks--;
1100                                                 if (limit) {
1101                                                         *limit = *limit - 1;
1102                                                         if (*limit <= 0) {
1103                                                                 hitLimit = 1;
1104                                                         }
1105                                                 }
1106
1107                                         }
1108
1109                                         yaffs_PutLevel0Tnode(dev,tn,i,0);
1110                                 }
1111
1112                         }
1113                         return (i < 0) ? 1 : 0;
1114
1115                 }
1116
1117         }
1118
1119         return 1;
1120
1121 }
1122
1123 static void yaffs_SoftDeleteChunk(yaffs_Device * dev, int chunk)
1124 {
1125
1126         yaffs_BlockInfo *theBlock;
1127
1128         T(YAFFS_TRACE_DELETION, (TSTR("soft delete chunk %d" TENDSTR), chunk));
1129
1130         theBlock = yaffs_GetBlockInfo(dev, chunk / dev->nChunksPerBlock);
1131         if (theBlock) {
1132                 theBlock->softDeletions++;
1133                 dev->nFreeChunks++;
1134         }
1135 }
1136
1137 /* SoftDeleteWorker scans backwards through the tnode tree and soft deletes all the chunks in the file.
1138  * All soft deleting does is increment the block's softdelete count and pulls the chunk out
1139  * of the tnode.
1140  * Thus, essentially this is the same as DeleteWorker except that the chunks are soft deleted.
1141  */
1142
1143 static int yaffs_SoftDeleteWorker(yaffs_Object * in, yaffs_Tnode * tn,
1144                                   __u32 level, int chunkOffset)
1145 {
1146         int i;
1147         int theChunk;
1148         int allDone = 1;
1149         yaffs_Device *dev = in->myDev;
1150
1151         if (tn) {
1152                 if (level > 0) {
1153
1154                         for (i = YAFFS_NTNODES_INTERNAL - 1; allDone && i >= 0;
1155                              i--) {
1156                                 if (tn->internal[i]) {
1157                                         allDone =
1158                                             yaffs_SoftDeleteWorker(in,
1159                                                                    tn->
1160                                                                    internal[i],
1161                                                                    level - 1,
1162                                                                    (chunkOffset
1163                                                                     <<
1164                                                                     YAFFS_TNODES_INTERNAL_BITS)
1165                                                                    + i);
1166                                         if (allDone) {
1167                                                 yaffs_FreeTnode(dev,
1168                                                                 tn->
1169                                                                 internal[i]);
1170                                                 tn->internal[i] = NULL;
1171                                         } else {
1172                                                 /* Hoosterman... how could this happen? */
1173                                         }
1174                                 }
1175                         }
1176                         return (allDone) ? 1 : 0;
1177                 } else if (level == 0) {
1178
1179                         for (i = YAFFS_NTNODES_LEVEL0 - 1; i >= 0; i--) {
1180                                 theChunk = yaffs_GetChunkGroupBase(dev,tn,i);
1181                                 if (theChunk) {
1182                                         /* Note this does not find the real chunk, only the chunk group.
1183                                          * We make an assumption that a chunk group is not larger than
1184                                          * a block.
1185                                          */
1186                                         yaffs_SoftDeleteChunk(dev, theChunk);
1187                                         yaffs_PutLevel0Tnode(dev,tn,i,0);
1188                                 }
1189
1190                         }
1191                         return 1;
1192
1193                 }
1194
1195         }
1196
1197         return 1;
1198
1199 }
1200
1201 static void yaffs_SoftDeleteFile(yaffs_Object * obj)
1202 {
1203         if (obj->deleted &&
1204             obj->variantType == YAFFS_OBJECT_TYPE_FILE && !obj->softDeleted) {
1205                 if (obj->nDataChunks <= 0) {
1206                         /* Empty file with no duplicate object headers, just delete it immediately */
1207                         yaffs_FreeTnode(obj->myDev,
1208                                         obj->variant.fileVariant.top);
1209                         obj->variant.fileVariant.top = NULL;
1210                         T(YAFFS_TRACE_TRACING,
1211                           (TSTR("yaffs: Deleting empty file %d" TENDSTR),
1212                            obj->objectId));
1213                         yaffs_DoGenericObjectDeletion(obj);
1214                 } else {
1215                         yaffs_SoftDeleteWorker(obj,
1216                                                obj->variant.fileVariant.top,
1217                                                obj->variant.fileVariant.
1218                                                topLevel, 0);
1219                         obj->softDeleted = 1;
1220                 }
1221         }
1222 }
1223
1224 /* Pruning removes any part of the file structure tree that is beyond the
1225  * bounds of the file (ie that does not point to chunks).
1226  *
1227  * A file should only get pruned when its size is reduced.
1228  *
1229  * Before pruning, the chunks must be pulled from the tree and the
1230  * level 0 tnode entries must be zeroed out.
1231  * Could also use this for file deletion, but that's probably better handled
1232  * by a special case.
1233  */
1234
1235 static yaffs_Tnode *yaffs_PruneWorker(yaffs_Device * dev, yaffs_Tnode * tn,
1236                                       __u32 level, int del0)
1237 {
1238         int i;
1239         int hasData;
1240
1241         if (tn) {
1242                 hasData = 0;
1243
1244                 for (i = 0; i < YAFFS_NTNODES_INTERNAL; i++) {
1245                         if (tn->internal[i] && level > 0) {
1246                                 tn->internal[i] =
1247                                     yaffs_PruneWorker(dev, tn->internal[i],
1248                                                       level - 1,
1249                                                       (i == 0) ? del0 : 1);
1250                         }
1251
1252                         if (tn->internal[i]) {
1253                                 hasData++;
1254                         }
1255                 }
1256
1257                 if (hasData == 0 && del0) {
1258                         /* Free and return NULL */
1259
1260                         yaffs_FreeTnode(dev, tn);
1261                         tn = NULL;
1262                 }
1263
1264         }
1265
1266         return tn;
1267
1268 }
1269
1270 static int yaffs_PruneFileStructure(yaffs_Device * dev,
1271                                     yaffs_FileStructure * fStruct)
1272 {
1273         int i;
1274         int hasData;
1275         int done = 0;
1276         yaffs_Tnode *tn;
1277
1278         if (fStruct->topLevel > 0) {
1279                 fStruct->top =
1280                     yaffs_PruneWorker(dev, fStruct->top, fStruct->topLevel, 0);
1281
1282                 /* Now we have a tree with all the non-zero branches NULL but the height
1283                  * is the same as it was.
1284                  * Let's see if we can trim internal tnodes to shorten the tree.
1285                  * We can do this if only the 0th element in the tnode is in use
1286                  * (ie all the non-zero are NULL)
1287                  */
1288
1289                 while (fStruct->topLevel && !done) {
1290                         tn = fStruct->top;
1291
1292                         hasData = 0;
1293                         for (i = 1; i < YAFFS_NTNODES_INTERNAL; i++) {
1294                                 if (tn->internal[i]) {
1295                                         hasData++;
1296                                 }
1297                         }
1298
1299                         if (!hasData) {
1300                                 fStruct->top = tn->internal[0];
1301                                 fStruct->topLevel--;
1302                                 yaffs_FreeTnode(dev, tn);
1303                         } else {
1304                                 done = 1;
1305                         }
1306                 }
1307         }
1308
1309         return YAFFS_OK;
1310 }
1311
1312 /*-------------------- End of File Structure functions.-------------------*/
1313
1314 /* yaffs_CreateFreeObjects creates a bunch more objects and
1315  * adds them to the object free list.
1316  */
1317 static int yaffs_CreateFreeObjects(yaffs_Device * dev, int nObjects)
1318 {
1319         int i;
1320         yaffs_Object *newObjects;
1321         yaffs_ObjectList *list;
1322
1323         if (nObjects < 1)
1324                 return YAFFS_OK;
1325
1326         /* make these things */
1327         newObjects = YMALLOC(nObjects * sizeof(yaffs_Object));
1328
1329         if (!newObjects) {
1330                 T(YAFFS_TRACE_ALLOCATE,
1331                   (TSTR("yaffs: Could not allocate more objects" TENDSTR)));
1332                 return YAFFS_FAIL;
1333         }
1334
1335         /* Hook them into the free list */
1336         for (i = 0; i < nObjects - 1; i++) {
1337                 newObjects[i].siblings.next =
1338                     (struct list_head *)(&newObjects[i + 1]);
1339         }
1340
1341         newObjects[nObjects - 1].siblings.next = (void *)dev->freeObjects;
1342         dev->freeObjects = newObjects;
1343         dev->nFreeObjects += nObjects;
1344         dev->nObjectsCreated += nObjects;
1345
1346         /* Now add this bunch of Objects to a list for freeing up. */
1347
1348         list = YMALLOC(sizeof(yaffs_ObjectList));
1349         if (!list) {
1350                 T(YAFFS_TRACE_ALLOCATE,
1351                   (TSTR("Could not add objects to management list" TENDSTR)));
1352         } else {
1353                 list->objects = newObjects;
1354                 list->next = dev->allocatedObjectList;
1355                 dev->allocatedObjectList = list;
1356         }
1357
1358         return YAFFS_OK;
1359 }
1360
1361
1362 /* AllocateEmptyObject gets us a clean Object. Tries to make allocate more if we run out */
1363 static yaffs_Object *yaffs_AllocateEmptyObject(yaffs_Device * dev)
1364 {
1365         yaffs_Object *tn = NULL;
1366
1367         /* If there are none left make more */
1368         if (!dev->freeObjects) {
1369                 yaffs_CreateFreeObjects(dev, YAFFS_ALLOCATION_NOBJECTS);
1370         }
1371
1372         if (dev->freeObjects) {
1373                 tn = dev->freeObjects;
1374                 dev->freeObjects =
1375                     (yaffs_Object *) (dev->freeObjects->siblings.next);
1376                 dev->nFreeObjects--;
1377
1378                 /* Now sweeten it up... */
1379
1380                 memset(tn, 0, sizeof(yaffs_Object));
1381                 tn->myDev = dev;
1382                 tn->chunkId = -1;
1383                 tn->variantType = YAFFS_OBJECT_TYPE_UNKNOWN;
1384                 INIT_LIST_HEAD(&(tn->hardLinks));
1385                 INIT_LIST_HEAD(&(tn->hashLink));
1386                 INIT_LIST_HEAD(&tn->siblings);
1387
1388                 /* Add it to the lost and found directory.
1389                  * NB Can't put root or lostNFound in lostNFound so
1390                  * check if lostNFound exists first
1391                  */
1392                 if (dev->lostNFoundDir) {
1393                         yaffs_AddObjectToDirectory(dev->lostNFoundDir, tn);
1394                 }
1395         }
1396
1397         return tn;
1398 }
1399
1400 static yaffs_Object *yaffs_CreateFakeDirectory(yaffs_Device * dev, int number,
1401                                                __u32 mode)
1402 {
1403
1404         yaffs_Object *obj =
1405             yaffs_CreateNewObject(dev, number, YAFFS_OBJECT_TYPE_DIRECTORY);
1406         if (obj) {
1407                 obj->fake = 1;          /* it is fake so it has no NAND presence... */
1408                 obj->renameAllowed = 0; /* ... and we're not allowed to rename it... */
1409                 obj->unlinkAllowed = 0; /* ... or unlink it */
1410                 obj->deleted = 0;
1411                 obj->unlinked = 0;
1412                 obj->yst_mode = mode;
1413                 obj->myDev = dev;
1414                 obj->chunkId = 0;       /* Not a valid chunk. */
1415         }
1416
1417         return obj;
1418
1419 }
1420
1421 static void yaffs_UnhashObject(yaffs_Object * tn)
1422 {
1423         int bucket;
1424         yaffs_Device *dev = tn->myDev;
1425
1426         /* If it is still linked into the bucket list, free from the list */
1427         if (!list_empty(&tn->hashLink)) {
1428                 list_del_init(&tn->hashLink);
1429                 bucket = yaffs_HashFunction(tn->objectId);
1430                 dev->objectBucket[bucket].count--;
1431         }
1432
1433 }
1434
1435 /*  FreeObject frees up a Object and puts it back on the free list */
1436 static void yaffs_FreeObject(yaffs_Object * tn)
1437 {
1438
1439         yaffs_Device *dev = tn->myDev;
1440
1441 #ifdef  __KERNEL__
1442         if (tn->myInode) {
1443                 /* We're still hooked up to a cached inode.
1444                  * Don't delete now, but mark for later deletion
1445                  */
1446                 tn->deferedFree = 1;
1447                 return;
1448         }
1449 #endif
1450
1451         yaffs_UnhashObject(tn);
1452
1453         /* Link into the free list. */
1454         tn->siblings.next = (struct list_head *)(dev->freeObjects);
1455         dev->freeObjects = tn;
1456         dev->nFreeObjects++;
1457 }
1458
1459 #ifdef __KERNEL__
1460
1461 void yaffs_HandleDeferedFree(yaffs_Object * obj)
1462 {
1463         if (obj->deferedFree) {
1464                 yaffs_FreeObject(obj);
1465         }
1466 }
1467
1468 #endif
1469
1470 static void yaffs_DeinitialiseObjects(yaffs_Device * dev)
1471 {
1472         /* Free the list of allocated Objects */
1473
1474         yaffs_ObjectList *tmp;
1475
1476         while (dev->allocatedObjectList) {
1477                 tmp = dev->allocatedObjectList->next;
1478                 YFREE(dev->allocatedObjectList->objects);
1479                 YFREE(dev->allocatedObjectList);
1480
1481                 dev->allocatedObjectList = tmp;
1482         }
1483
1484         dev->freeObjects = NULL;
1485         dev->nFreeObjects = 0;
1486 }
1487
1488 static void yaffs_InitialiseObjects(yaffs_Device * dev)
1489 {
1490         int i;
1491
1492         dev->allocatedObjectList = NULL;
1493         dev->freeObjects = NULL;
1494         dev->nFreeObjects = 0;
1495
1496         for (i = 0; i < YAFFS_NOBJECT_BUCKETS; i++) {
1497                 INIT_LIST_HEAD(&dev->objectBucket[i].list);
1498                 dev->objectBucket[i].count = 0;
1499         }
1500
1501 }
1502
1503 static int yaffs_FindNiceObjectBucket(yaffs_Device * dev)
1504 {
1505         static int x = 0;
1506         int i;
1507         int l = 999;
1508         int lowest = 999999;
1509
1510         /* First let's see if we can find one that's empty. */
1511
1512         for (i = 0; i < 10 && lowest > 0; i++) {
1513                 x++;
1514                 x %= YAFFS_NOBJECT_BUCKETS;
1515                 if (dev->objectBucket[x].count < lowest) {
1516                         lowest = dev->objectBucket[x].count;
1517                         l = x;
1518                 }
1519
1520         }
1521
1522         /* If we didn't find an empty list, then try
1523          * looking a bit further for a short one
1524          */
1525
1526         for (i = 0; i < 10 && lowest > 3; i++) {
1527                 x++;
1528                 x %= YAFFS_NOBJECT_BUCKETS;
1529                 if (dev->objectBucket[x].count < lowest) {
1530                         lowest = dev->objectBucket[x].count;
1531                         l = x;
1532                 }
1533
1534         }
1535
1536         return l;
1537 }
1538
1539 static int yaffs_CreateNewObjectNumber(yaffs_Device * dev)
1540 {
1541         int bucket = yaffs_FindNiceObjectBucket(dev);
1542
1543         /* Now find an object value that has not already been taken
1544          * by scanning the list.
1545          */
1546
1547         int found = 0;
1548         struct list_head *i;
1549
1550         __u32 n = (__u32) bucket;
1551
1552         /* yaffs_CheckObjectHashSanity();  */
1553
1554         while (!found) {
1555                 found = 1;
1556                 n += YAFFS_NOBJECT_BUCKETS;
1557                 if (1 || dev->objectBucket[bucket].count > 0) {
1558                         list_for_each(i, &dev->objectBucket[bucket].list) {
1559                                 /* If there is already one in the list */
1560                                 if (i
1561                                     && list_entry(i, yaffs_Object,
1562                                                   hashLink)->objectId == n) {
1563                                         found = 0;
1564                                 }
1565                         }
1566                 }
1567         }
1568
1569
1570         return n;
1571 }
1572
1573 static void yaffs_HashObject(yaffs_Object * in)
1574 {
1575         int bucket = yaffs_HashFunction(in->objectId);
1576         yaffs_Device *dev = in->myDev;
1577
1578         list_add(&in->hashLink, &dev->objectBucket[bucket].list);
1579         dev->objectBucket[bucket].count++;
1580
1581 }
1582
1583 yaffs_Object *yaffs_FindObjectByNumber(yaffs_Device * dev, __u32 number)
1584 {
1585         int bucket = yaffs_HashFunction(number);
1586         struct list_head *i;
1587         yaffs_Object *in;
1588
1589         list_for_each(i, &dev->objectBucket[bucket].list) {
1590                 /* Look if it is in the list */
1591                 if (i) {
1592                         in = list_entry(i, yaffs_Object, hashLink);
1593                         if (in->objectId == number) {
1594 #ifdef __KERNEL__
1595                                 /* Don't tell the VFS about this one if it is defered free */
1596                                 if (in->deferedFree)
1597                                         return NULL;
1598 #endif
1599
1600                                 return in;
1601                         }
1602                 }
1603         }
1604
1605         return NULL;
1606 }
1607
1608 yaffs_Object *yaffs_CreateNewObject(yaffs_Device * dev, int number,
1609                                     yaffs_ObjectType type)
1610 {
1611
1612         yaffs_Object *theObject;
1613
1614         if (number < 0) {
1615                 number = yaffs_CreateNewObjectNumber(dev);
1616         }
1617
1618         theObject = yaffs_AllocateEmptyObject(dev);
1619
1620         if (theObject) {
1621                 theObject->fake = 0;
1622                 theObject->renameAllowed = 1;
1623                 theObject->unlinkAllowed = 1;
1624                 theObject->objectId = number;
1625                 yaffs_HashObject(theObject);
1626                 theObject->variantType = type;
1627 #ifdef CONFIG_YAFFS_WINCE
1628                 yfsd_WinFileTimeNow(theObject->win_atime);
1629                 theObject->win_ctime[0] = theObject->win_mtime[0] =
1630                     theObject->win_atime[0];
1631                 theObject->win_ctime[1] = theObject->win_mtime[1] =
1632                     theObject->win_atime[1];
1633
1634 #else
1635
1636                 theObject->yst_atime = theObject->yst_mtime =
1637                     theObject->yst_ctime = Y_CURRENT_TIME;
1638 #endif
1639                 switch (type) {
1640                 case YAFFS_OBJECT_TYPE_FILE:
1641                         theObject->variant.fileVariant.fileSize = 0;
1642                         theObject->variant.fileVariant.scannedFileSize = 0;
1643                         theObject->variant.fileVariant.shrinkSize = 0xFFFFFFFF; /* max __u32 */
1644                         theObject->variant.fileVariant.topLevel = 0;
1645                         theObject->variant.fileVariant.top =
1646                             yaffs_GetTnode(dev);
1647                         break;
1648                 case YAFFS_OBJECT_TYPE_DIRECTORY:
1649                         INIT_LIST_HEAD(&theObject->variant.directoryVariant.
1650                                        children);
1651                         break;
1652                 case YAFFS_OBJECT_TYPE_SYMLINK:
1653                 case YAFFS_OBJECT_TYPE_HARDLINK:
1654                 case YAFFS_OBJECT_TYPE_SPECIAL:
1655                         /* No action required */
1656                         break;
1657                 case YAFFS_OBJECT_TYPE_UNKNOWN:
1658                         /* todo this should not happen */
1659                         break;
1660                 }
1661         }
1662
1663         return theObject;
1664 }
1665
1666 static yaffs_Object *yaffs_FindOrCreateObjectByNumber(yaffs_Device * dev,
1667                                                       int number,
1668                                                       yaffs_ObjectType type)
1669 {
1670         yaffs_Object *theObject = NULL;
1671
1672         if (number > 0) {
1673                 theObject = yaffs_FindObjectByNumber(dev, number);
1674         }
1675
1676         if (!theObject) {
1677                 theObject = yaffs_CreateNewObject(dev, number, type);
1678         }
1679
1680         return theObject;
1681
1682 }
1683
1684
1685 static YCHAR *yaffs_CloneString(const YCHAR * str)
1686 {
1687         YCHAR *newStr = NULL;
1688
1689         if (str && *str) {
1690                 newStr = YMALLOC((yaffs_strlen(str) + 1) * sizeof(YCHAR));
1691                 yaffs_strcpy(newStr, str);
1692         }
1693
1694         return newStr;
1695
1696 }
1697
1698 /*
1699  * Mknod (create) a new object.
1700  * equivalentObject only has meaning for a hard link;
1701  * aliasString only has meaning for a sumlink.
1702  * rdev only has meaning for devices (a subset of special objects)
1703  */
1704
1705 static yaffs_Object *yaffs_MknodObject(yaffs_ObjectType type,
1706                                        yaffs_Object * parent,
1707                                        const YCHAR * name,
1708                                        __u32 mode,
1709                                        __u32 uid,
1710                                        __u32 gid,
1711                                        yaffs_Object * equivalentObject,
1712                                        const YCHAR * aliasString, __u32 rdev)
1713 {
1714         yaffs_Object *in;
1715
1716         yaffs_Device *dev = parent->myDev;
1717
1718         /* Check if the entry exists. If it does then fail the call since we don't want a dup.*/
1719         if (yaffs_FindObjectByName(parent, name)) {
1720                 return NULL;
1721         }
1722
1723         in = yaffs_CreateNewObject(dev, -1, type);
1724
1725         if (in) {
1726                 in->chunkId = -1;
1727                 in->valid = 1;
1728                 in->variantType = type;
1729
1730                 in->yst_mode = mode;
1731
1732 #ifdef CONFIG_YAFFS_WINCE
1733                 yfsd_WinFileTimeNow(in->win_atime);
1734                 in->win_ctime[0] = in->win_mtime[0] = in->win_atime[0];
1735                 in->win_ctime[1] = in->win_mtime[1] = in->win_atime[1];
1736
1737 #else
1738                 in->yst_atime = in->yst_mtime = in->yst_ctime = Y_CURRENT_TIME;
1739
1740                 in->yst_rdev = rdev;
1741                 in->yst_uid = uid;
1742                 in->yst_gid = gid;
1743 #endif
1744                 in->nDataChunks = 0;
1745
1746                 yaffs_SetObjectName(in, name);
1747                 in->dirty = 1;
1748
1749                 yaffs_AddObjectToDirectory(parent, in);
1750
1751                 in->myDev = parent->myDev;
1752
1753                 switch (type) {
1754                 case YAFFS_OBJECT_TYPE_SYMLINK:
1755                         in->variant.symLinkVariant.alias =
1756                             yaffs_CloneString(aliasString);
1757                         break;
1758                 case YAFFS_OBJECT_TYPE_HARDLINK:
1759                         in->variant.hardLinkVariant.equivalentObject =
1760                             equivalentObject;
1761                         in->variant.hardLinkVariant.equivalentObjectId =
1762                             equivalentObject->objectId;
1763                         list_add(&in->hardLinks, &equivalentObject->hardLinks);
1764                         break;
1765                 case YAFFS_OBJECT_TYPE_FILE:
1766                 case YAFFS_OBJECT_TYPE_DIRECTORY:
1767                 case YAFFS_OBJECT_TYPE_SPECIAL:
1768                 case YAFFS_OBJECT_TYPE_UNKNOWN:
1769                         /* do nothing */
1770                         break;
1771                 }
1772
1773                 if (yaffs_UpdateObjectHeader(in, name, 0, 0, 0) < 0) {
1774                         /* Could not create the object header, fail the creation */
1775                         yaffs_DestroyObject(in);
1776                         in = NULL;
1777                 }
1778
1779         }
1780
1781         return in;
1782 }
1783
1784 yaffs_Object *yaffs_MknodFile(yaffs_Object * parent, const YCHAR * name,
1785                               __u32 mode, __u32 uid, __u32 gid)
1786 {
1787         return yaffs_MknodObject(YAFFS_OBJECT_TYPE_FILE, parent, name, mode,
1788                                  uid, gid, NULL, NULL, 0);
1789 }
1790
1791 yaffs_Object *yaffs_MknodDirectory(yaffs_Object * parent, const YCHAR * name,
1792                                    __u32 mode, __u32 uid, __u32 gid)
1793 {
1794         return yaffs_MknodObject(YAFFS_OBJECT_TYPE_DIRECTORY, parent, name,
1795                                  mode, uid, gid, NULL, NULL, 0);
1796 }
1797
1798 yaffs_Object *yaffs_MknodSpecial(yaffs_Object * parent, const YCHAR * name,
1799                                  __u32 mode, __u32 uid, __u32 gid, __u32 rdev)
1800 {
1801         return yaffs_MknodObject(YAFFS_OBJECT_TYPE_SPECIAL, parent, name, mode,
1802                                  uid, gid, NULL, NULL, rdev);
1803 }
1804
1805 yaffs_Object *yaffs_MknodSymLink(yaffs_Object * parent, const YCHAR * name,
1806                                  __u32 mode, __u32 uid, __u32 gid,
1807                                  const YCHAR * alias)
1808 {
1809         return yaffs_MknodObject(YAFFS_OBJECT_TYPE_SYMLINK, parent, name, mode,
1810                                  uid, gid, NULL, alias, 0);
1811 }
1812
1813 /* yaffs_Link returns the object id of the equivalent object.*/
1814 yaffs_Object *yaffs_Link(yaffs_Object * parent, const YCHAR * name,
1815                          yaffs_Object * equivalentObject)
1816 {
1817         /* Get the real object in case we were fed a hard link as an equivalent object */
1818         equivalentObject = yaffs_GetEquivalentObject(equivalentObject);
1819
1820         if (yaffs_MknodObject
1821             (YAFFS_OBJECT_TYPE_HARDLINK, parent, name, 0, 0, 0,
1822              equivalentObject, NULL, 0)) {
1823                 return equivalentObject;
1824         } else {
1825                 return NULL;
1826         }
1827
1828 }
1829
1830 static int yaffs_ChangeObjectName(yaffs_Object * obj, yaffs_Object * newDir,
1831                                   const YCHAR * newName, int force, int shadows)
1832 {
1833         int unlinkOp;
1834         int deleteOp;
1835
1836         yaffs_Object *existingTarget;
1837
1838         if (newDir == NULL) {
1839                 newDir = obj->parent;   /* use the old directory */
1840         }
1841
1842         if (newDir->variantType != YAFFS_OBJECT_TYPE_DIRECTORY) {
1843                 T(YAFFS_TRACE_ALWAYS,
1844                   (TSTR
1845                    ("tragendy: yaffs_ChangeObjectName: newDir is not a directory"
1846                     TENDSTR)));
1847                 YBUG();
1848         }
1849
1850         /* TODO: Do we need this different handling for YAFFS2 and YAFFS1?? */
1851         if (obj->myDev->isYaffs2) {
1852                 unlinkOp = (newDir == obj->myDev->unlinkedDir);
1853         } else {
1854                 unlinkOp = (newDir == obj->myDev->unlinkedDir
1855                             && obj->variantType == YAFFS_OBJECT_TYPE_FILE);
1856         }
1857
1858         deleteOp = (newDir == obj->myDev->deletedDir);
1859
1860         existingTarget = yaffs_FindObjectByName(newDir, newName);
1861
1862         /* If the object is a file going into the unlinked directory,
1863          *   then it is OK to just stuff it in since duplicate names are allowed.
1864          *   else only proceed if the new name does not exist and if we're putting
1865          *   it into a directory.
1866          */
1867         if ((unlinkOp ||
1868              deleteOp ||
1869              force ||
1870              (shadows > 0) ||
1871              !existingTarget) &&
1872             newDir->variantType == YAFFS_OBJECT_TYPE_DIRECTORY) {
1873                 yaffs_SetObjectName(obj, newName);
1874                 obj->dirty = 1;
1875
1876                 yaffs_AddObjectToDirectory(newDir, obj);
1877
1878                 if (unlinkOp)
1879                         obj->unlinked = 1;
1880
1881                 /* If it is a deletion then we mark it as a shrink for gc purposes. */
1882                 if (yaffs_UpdateObjectHeader(obj, newName, 0, deleteOp, shadows)>= 0)
1883                         return YAFFS_OK;
1884         }
1885
1886         return YAFFS_FAIL;
1887 }
1888
1889 int yaffs_RenameObject(yaffs_Object * oldDir, const YCHAR * oldName,
1890                        yaffs_Object * newDir, const YCHAR * newName)
1891 {
1892         yaffs_Object *obj;
1893         yaffs_Object *existingTarget;
1894         int force = 0;
1895
1896 #ifdef CONFIG_YAFFS_CASE_INSENSITIVE
1897         /* Special case for case insemsitive systems (eg. WinCE).
1898          * While look-up is case insensitive, the name isn't.
1899          * Therefore we might want to change x.txt to X.txt
1900         */
1901         if (oldDir == newDir && yaffs_strcmp(oldName, newName) == 0) {
1902                 force = 1;
1903         }
1904 #endif
1905
1906         obj = yaffs_FindObjectByName(oldDir, oldName);
1907         /* Check new name to long. */
1908         if (obj->variantType == YAFFS_OBJECT_TYPE_SYMLINK &&
1909             yaffs_strlen(newName) > YAFFS_MAX_ALIAS_LENGTH)
1910           /* ENAMETOOLONG */
1911           return YAFFS_FAIL;
1912         else if (obj->variantType != YAFFS_OBJECT_TYPE_SYMLINK &&
1913                  yaffs_strlen(newName) > YAFFS_MAX_NAME_LENGTH)
1914           /* ENAMETOOLONG */
1915           return YAFFS_FAIL;
1916
1917         if (obj && obj->renameAllowed) {
1918
1919                 /* Now do the handling for an existing target, if there is one */
1920
1921                 existingTarget = yaffs_FindObjectByName(newDir, newName);
1922                 if (existingTarget &&
1923                     existingTarget->variantType == YAFFS_OBJECT_TYPE_DIRECTORY &&
1924                     !list_empty(&existingTarget->variant.directoryVariant.children)) {
1925                         /* There is a target that is a non-empty directory, so we fail */
1926                         return YAFFS_FAIL;      /* EEXIST or ENOTEMPTY */
1927                 } else if (existingTarget && existingTarget != obj) {
1928                         /* Nuke the target first, using shadowing,
1929                          * but only if it isn't the same object
1930                          */
1931                         yaffs_ChangeObjectName(obj, newDir, newName, force,
1932                                                existingTarget->objectId);
1933                         yaffs_UnlinkObject(existingTarget);
1934                 }
1935
1936                 return yaffs_ChangeObjectName(obj, newDir, newName, 1, 0);
1937         }
1938         return YAFFS_FAIL;
1939 }
1940
1941 /*------------------------- Block Management and Page Allocation ----------------*/
1942
1943 static int yaffs_InitialiseBlocks(yaffs_Device * dev)
1944 {
1945         int nBlocks = dev->internalEndBlock - dev->internalStartBlock + 1;
1946
1947         dev->allocationBlock = -1;      /* force it to get a new one */
1948
1949         /* Todo we're assuming the malloc will pass. */
1950         dev->blockInfo = YMALLOC(nBlocks * sizeof(yaffs_BlockInfo));
1951         if(!dev->blockInfo){
1952                 dev->blockInfo = YMALLOC_ALT(nBlocks * sizeof(yaffs_BlockInfo));
1953                 dev->blockInfoAlt = 1;
1954         }
1955         else
1956                 dev->blockInfoAlt = 0;
1957
1958         /* Set up dynamic blockinfo stuff. */
1959         dev->chunkBitmapStride = (dev->nChunksPerBlock + 7) / 8; /* round up bytes */
1960         dev->chunkBits = YMALLOC(dev->chunkBitmapStride * nBlocks);
1961         if(!dev->chunkBits){
1962                 dev->chunkBits = YMALLOC_ALT(dev->chunkBitmapStride * nBlocks);
1963                 dev->chunkBitsAlt = 1;
1964         }
1965         else
1966                 dev->chunkBitsAlt = 0;
1967
1968         if (dev->blockInfo && dev->chunkBits) {
1969                 memset(dev->blockInfo, 0, nBlocks * sizeof(yaffs_BlockInfo));
1970                 memset(dev->chunkBits, 0, dev->chunkBitmapStride * nBlocks);
1971                 return YAFFS_OK;
1972         }
1973
1974         return YAFFS_FAIL;
1975
1976 }
1977
1978 static void yaffs_DeinitialiseBlocks(yaffs_Device * dev)
1979 {
1980         if(dev->blockInfoAlt)
1981                 YFREE_ALT(dev->blockInfo);
1982         else
1983                 YFREE(dev->blockInfo);
1984         dev->blockInfoAlt = 0;
1985
1986         dev->blockInfo = NULL;
1987
1988         if(dev->chunkBitsAlt)
1989                 YFREE_ALT(dev->chunkBits);
1990         else
1991                 YFREE(dev->chunkBits);
1992         dev->chunkBitsAlt = 0;
1993         dev->chunkBits = NULL;
1994 }
1995
1996 static int yaffs_BlockNotDisqualifiedFromGC(yaffs_Device * dev,
1997                                             yaffs_BlockInfo * bi)
1998 {
1999         int i;
2000         __u32 seq;
2001         yaffs_BlockInfo *b;
2002
2003         if (!dev->isYaffs2)
2004                 return 1;       /* disqualification only applies to yaffs2. */
2005
2006         if (!bi->hasShrinkHeader)
2007                 return 1;       /* can gc */
2008
2009         /* Find the oldest dirty sequence number if we don't know it and save it
2010          * so we don't have to keep recomputing it.
2011          */
2012         if (!dev->oldestDirtySequence) {
2013                 seq = dev->sequenceNumber;
2014
2015                 for (i = dev->internalStartBlock; i <= dev->internalEndBlock;
2016                      i++) {
2017                         b = yaffs_GetBlockInfo(dev, i);
2018                         if (b->blockState == YAFFS_BLOCK_STATE_FULL &&
2019                             (b->pagesInUse - b->softDeletions) <
2020                             dev->nChunksPerBlock && b->sequenceNumber < seq) {
2021                                 seq = b->sequenceNumber;
2022                         }
2023                 }
2024                 dev->oldestDirtySequence = seq;
2025         }
2026
2027         /* Can't do gc of this block if there are any blocks older than this one that have
2028          * discarded pages.
2029          */
2030         return (bi->sequenceNumber <= dev->oldestDirtySequence);
2031
2032 }
2033
2034 /* FindDiretiestBlock is used to select the dirtiest block (or close enough)
2035  * for garbage collection.
2036  */
2037
2038 static int yaffs_FindBlockForGarbageCollection(yaffs_Device * dev,
2039                                                int aggressive)
2040 {
2041
2042         int b = dev->currentDirtyChecker;
2043
2044         int i;
2045         int iterations;
2046         int dirtiest = -1;
2047         int pagesInUse;
2048         int prioritised=0;
2049         yaffs_BlockInfo *bi;
2050         static int nonAggressiveSkip = 0;
2051         int pendingPrioritisedExist = 0;
2052
2053         /* First let's see if we need to grab a prioritised block */
2054         if(dev->hasPendingPrioritisedGCs){
2055                 for(i = dev->internalStartBlock; i < dev->internalEndBlock && !prioritised; i++){
2056
2057                         bi = yaffs_GetBlockInfo(dev, i);
2058                         if(bi->gcPrioritise) {
2059                                 pendingPrioritisedExist = 1;
2060                                 if(bi->blockState == YAFFS_BLOCK_STATE_FULL &&
2061                                    yaffs_BlockNotDisqualifiedFromGC(dev, bi)){
2062                                         pagesInUse = (bi->pagesInUse - bi->softDeletions);
2063                                         dirtiest = i;
2064                                         prioritised = 1;
2065                                         aggressive = 1; /* Fool the non-aggressive skip logiv below */
2066                                 }
2067                         }
2068                 }
2069
2070                 if(!pendingPrioritisedExist) /* None found, so we can clear this */
2071                         dev->hasPendingPrioritisedGCs = 0;
2072         }
2073
2074         /* If we're doing aggressive GC then we are happy to take a less-dirty block, and
2075          * search harder.
2076          * else (we're doing a leasurely gc), then we only bother to do this if the
2077          * block has only a few pages in use.
2078          */
2079
2080         nonAggressiveSkip--;
2081
2082         if (!aggressive && (nonAggressiveSkip > 0)) {
2083                 return -1;
2084         }
2085
2086         if(!prioritised)
2087                 pagesInUse =
2088                         (aggressive) ? dev->nChunksPerBlock : YAFFS_PASSIVE_GC_CHUNKS + 1;
2089
2090         if (aggressive) {
2091                 iterations =
2092                     dev->internalEndBlock - dev->internalStartBlock + 1;
2093         } else {
2094                 iterations =
2095                     dev->internalEndBlock - dev->internalStartBlock + 1;
2096                 iterations = iterations / 16;
2097                 if (iterations > 200) {
2098                         iterations = 200;
2099                 }
2100         }
2101
2102         for (i = 0; i <= iterations && pagesInUse > 0 && !prioritised; i++) {
2103                 b++;
2104                 if (b < dev->internalStartBlock || b > dev->internalEndBlock) {
2105                         b = dev->internalStartBlock;
2106                 }
2107
2108                 if (b < dev->internalStartBlock || b > dev->internalEndBlock) {
2109                         T(YAFFS_TRACE_ERROR,
2110                           (TSTR("**>> Block %d is not valid" TENDSTR), b));
2111                         YBUG();
2112                 }
2113
2114                 bi = yaffs_GetBlockInfo(dev, b);
2115
2116 #if 0
2117                 if (bi->blockState == YAFFS_BLOCK_STATE_CHECKPOINT) {
2118                         dirtiest = b;
2119                         pagesInUse = 0;
2120                 }
2121                 else
2122 #endif
2123
2124                 if (bi->blockState == YAFFS_BLOCK_STATE_FULL &&
2125                        (bi->pagesInUse - bi->softDeletions) < pagesInUse &&
2126                         yaffs_BlockNotDisqualifiedFromGC(dev, bi)) {
2127                         dirtiest = b;
2128                         pagesInUse = (bi->pagesInUse - bi->softDeletions);
2129                 }
2130         }
2131
2132         dev->currentDirtyChecker = b;
2133
2134         if (dirtiest > 0) {
2135                 T(YAFFS_TRACE_GC,
2136                   (TSTR("GC Selected block %d with %d free, prioritised:%d" TENDSTR), dirtiest,
2137                    dev->nChunksPerBlock - pagesInUse,prioritised));
2138         }
2139
2140         dev->oldestDirtySequence = 0;
2141
2142         if (dirtiest > 0) {
2143                 nonAggressiveSkip = 4;
2144         }
2145
2146         return dirtiest;
2147 }
2148
2149 static void yaffs_BlockBecameDirty(yaffs_Device * dev, int blockNo)
2150 {
2151         yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, blockNo);
2152
2153         int erasedOk = 0;
2154
2155         /* If the block is still healthy erase it and mark as clean.
2156          * If the block has had a data failure, then retire it.
2157          */
2158
2159         T(YAFFS_TRACE_GC | YAFFS_TRACE_ERASE,
2160                 (TSTR("yaffs_BlockBecameDirty block %d state %d %s"TENDSTR),
2161                 blockNo, bi->blockState, (bi->needsRetiring) ? "needs retiring" : ""));
2162
2163         bi->blockState = YAFFS_BLOCK_STATE_DIRTY;
2164
2165         if (!bi->needsRetiring) {
2166                 yaffs_InvalidateCheckpoint(dev);
2167                 erasedOk = yaffs_EraseBlockInNAND(dev, blockNo);
2168                 if (!erasedOk) {
2169                         dev->nErasureFailures++;
2170                         T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
2171                           (TSTR("**>> Erasure failed %d" TENDSTR), blockNo));
2172                 }
2173         }
2174
2175         if (erasedOk && (yaffs_traceMask & YAFFS_TRACE_ERASE)) {
2176                 int i;
2177                 for (i = 0; i < dev->nChunksPerBlock; i++) {
2178                         if (!yaffs_CheckChunkErased
2179                             (dev, blockNo * dev->nChunksPerBlock + i)) {
2180                                 T(YAFFS_TRACE_ERROR,
2181                                   (TSTR
2182                                    (">>Block %d erasure supposedly OK, but chunk %d not erased"
2183                                     TENDSTR), blockNo, i));
2184                         }
2185                 }
2186         }
2187
2188         if (erasedOk) {
2189                 /* Clean it up... */
2190                 bi->blockState = YAFFS_BLOCK_STATE_EMPTY;
2191                 dev->nErasedBlocks++;
2192                 bi->pagesInUse = 0;
2193                 bi->softDeletions = 0;
2194                 bi->hasShrinkHeader = 0;
2195                 bi->skipErasedCheck = 1;  /* This is clean, so no need to check */
2196                 bi->gcPrioritise = 0;
2197                 yaffs_ClearChunkBits(dev, blockNo);
2198
2199                 T(YAFFS_TRACE_ERASE,
2200                   (TSTR("Erased block %d" TENDSTR), blockNo));
2201         } else {
2202                 dev->nFreeChunks -= dev->nChunksPerBlock;       /* We lost a block of free space */
2203
2204                 yaffs_RetireBlock(dev, blockNo);
2205                 T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
2206                   (TSTR("**>> Block %d retired" TENDSTR), blockNo));
2207         }
2208 }
2209
2210 static int yaffs_FindBlockForAllocation(yaffs_Device * dev)
2211 {
2212         int i;
2213
2214         yaffs_BlockInfo *bi;
2215
2216         if (dev->nErasedBlocks < 1) {
2217                 /* Hoosterman we've got a problem.
2218                  * Can't get space to gc
2219                  */
2220                 T(YAFFS_TRACE_ERROR,
2221                   (TSTR("yaffs tragedy: no more eraased blocks" TENDSTR)));
2222
2223                 return -1;
2224         }
2225
2226         /* Find an empty block. */
2227
2228         for (i = dev->internalStartBlock; i <= dev->internalEndBlock; i++) {
2229                 dev->allocationBlockFinder++;
2230                 if (dev->allocationBlockFinder < dev->internalStartBlock
2231                     || dev->allocationBlockFinder > dev->internalEndBlock) {
2232                         dev->allocationBlockFinder = dev->internalStartBlock;
2233                 }
2234
2235                 bi = yaffs_GetBlockInfo(dev, dev->allocationBlockFinder);
2236
2237                 if (bi->blockState == YAFFS_BLOCK_STATE_EMPTY) {
2238                         bi->blockState = YAFFS_BLOCK_STATE_ALLOCATING;
2239                         dev->sequenceNumber++;
2240                         bi->sequenceNumber = dev->sequenceNumber;
2241                         dev->nErasedBlocks--;
2242                         T(YAFFS_TRACE_ALLOCATE,
2243                           (TSTR("Allocated block %d, seq  %d, %d left" TENDSTR),
2244                            dev->allocationBlockFinder, dev->sequenceNumber,
2245                            dev->nErasedBlocks));
2246                         return dev->allocationBlockFinder;
2247                 }
2248         }
2249
2250         T(YAFFS_TRACE_ALWAYS,
2251           (TSTR
2252            ("yaffs tragedy: no more eraased blocks, but there should have been %d"
2253             TENDSTR), dev->nErasedBlocks));
2254
2255         return -1;
2256 }
2257
2258
2259 // Check if there's space to allocate...
2260 // Thinks.... do we need top make this ths same as yaffs_GetFreeChunks()?
2261 static int yaffs_CheckSpaceForAllocation(yaffs_Device * dev)
2262 {
2263         int reservedChunks;
2264         int reservedBlocks = dev->nReservedBlocks;
2265         int checkpointBlocks;
2266
2267         checkpointBlocks =  dev->nCheckpointReservedBlocks - dev->blocksInCheckpoint;
2268         if(checkpointBlocks < 0)
2269                 checkpointBlocks = 0;
2270
2271         reservedChunks = ((reservedBlocks + checkpointBlocks) * dev->nChunksPerBlock);
2272
2273         return (dev->nFreeChunks > reservedChunks);
2274 }
2275
2276 static int yaffs_AllocateChunk(yaffs_Device * dev, int useReserve, yaffs_BlockInfo **blockUsedPtr)
2277 {
2278         int retVal;
2279         yaffs_BlockInfo *bi;
2280
2281         if (dev->allocationBlock < 0) {
2282                 /* Get next block to allocate off */
2283                 dev->allocationBlock = yaffs_FindBlockForAllocation(dev);
2284                 dev->allocationPage = 0;
2285         }
2286
2287         if (!useReserve && !yaffs_CheckSpaceForAllocation(dev)) {
2288                 /* Not enough space to allocate unless we're allowed to use the reserve. */
2289                 return -1;
2290         }
2291
2292         if (dev->nErasedBlocks < dev->nReservedBlocks
2293             && dev->allocationPage == 0) {
2294                 T(YAFFS_TRACE_ALLOCATE, (TSTR("Allocating reserve" TENDSTR)));
2295         }
2296
2297         /* Next page please.... */
2298         if (dev->allocationBlock >= 0) {
2299                 bi = yaffs_GetBlockInfo(dev, dev->allocationBlock);
2300
2301                 retVal = (dev->allocationBlock * dev->nChunksPerBlock) +
2302                     dev->allocationPage;
2303                 bi->pagesInUse++;
2304                 yaffs_SetChunkBit(dev, dev->allocationBlock,
2305                                   dev->allocationPage);
2306
2307                 dev->allocationPage++;
2308
2309                 dev->nFreeChunks--;
2310
2311                 /* If the block is full set the state to full */
2312                 if (dev->allocationPage >= dev->nChunksPerBlock) {
2313                         bi->blockState = YAFFS_BLOCK_STATE_FULL;
2314                         dev->allocationBlock = -1;
2315                 }
2316
2317                 if(blockUsedPtr)
2318                         *blockUsedPtr = bi;
2319
2320                 return retVal;
2321         }
2322
2323         T(YAFFS_TRACE_ERROR,
2324           (TSTR("!!!!!!!!! Allocator out !!!!!!!!!!!!!!!!!" TENDSTR)));
2325
2326         return -1;
2327 }
2328
2329 static int yaffs_GetErasedChunks(yaffs_Device * dev)
2330 {
2331         int n;
2332
2333         n = dev->nErasedBlocks * dev->nChunksPerBlock;
2334
2335         if (dev->allocationBlock > 0) {
2336                 n += (dev->nChunksPerBlock - dev->allocationPage);
2337         }
2338
2339         return n;
2340
2341 }
2342
2343 static int yaffs_GarbageCollectBlock(yaffs_Device * dev, int block)
2344 {
2345         int oldChunk;
2346         int newChunk;
2347         int chunkInBlock;
2348         int markNAND;
2349         int retVal = YAFFS_OK;
2350         int cleanups = 0;
2351         int i;
2352         int isCheckpointBlock;
2353
2354         int chunksBefore = yaffs_GetErasedChunks(dev);
2355         int chunksAfter;
2356
2357         yaffs_ExtendedTags tags;
2358
2359         yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, block);
2360
2361         yaffs_Object *object;
2362
2363         isCheckpointBlock = (bi->blockState == YAFFS_BLOCK_STATE_CHECKPOINT);
2364
2365         bi->blockState = YAFFS_BLOCK_STATE_COLLECTING;
2366
2367         T(YAFFS_TRACE_TRACING,
2368           (TSTR("Collecting block %d, in use %d, shrink %d, " TENDSTR), block,
2369            bi->pagesInUse, bi->hasShrinkHeader));
2370
2371         /*yaffs_VerifyFreeChunks(dev); */
2372
2373         bi->hasShrinkHeader = 0;        /* clear the flag so that the block can erase */
2374
2375         /* Take off the number of soft deleted entries because
2376          * they're going to get really deleted during GC.
2377          */
2378         dev->nFreeChunks -= bi->softDeletions;
2379
2380         dev->isDoingGC = 1;
2381
2382         if (isCheckpointBlock ||
2383             !yaffs_StillSomeChunkBits(dev, block)) {
2384                 T(YAFFS_TRACE_TRACING,
2385                   (TSTR
2386                    ("Collecting block %d that has no chunks in use" TENDSTR),
2387                    block));
2388                 yaffs_BlockBecameDirty(dev, block);
2389         } else {
2390
2391                 __u8 *buffer = yaffs_GetTempBuffer(dev, __LINE__);
2392
2393                 for (chunkInBlock = 0, oldChunk = block * dev->nChunksPerBlock;
2394                      chunkInBlock < dev->nChunksPerBlock
2395                      && yaffs_StillSomeChunkBits(dev, block);
2396                      chunkInBlock++, oldChunk++) {
2397                         if (yaffs_CheckChunkBit(dev, block, chunkInBlock)) {
2398
2399                                 /* This page is in use and might need to be copied off */
2400
2401                                 markNAND = 1;
2402
2403                                 yaffs_InitialiseTags(&tags);
2404
2405                                 yaffs_ReadChunkWithTagsFromNAND(dev, oldChunk,
2406                                                                 buffer, &tags);
2407
2408                                 object =
2409                                     yaffs_FindObjectByNumber(dev,
2410                                                              tags.objectId);
2411
2412                                 T(YAFFS_TRACE_GC_DETAIL,
2413                                   (TSTR
2414                                    ("Collecting page %d, %d %d %d " TENDSTR),
2415                                    chunkInBlock, tags.objectId, tags.chunkId,
2416                                    tags.byteCount));
2417
2418                                 if (!object) {
2419                                         T(YAFFS_TRACE_ERROR,
2420                                           (TSTR
2421                                            ("page %d in gc has no object "
2422                                             TENDSTR), oldChunk));
2423                                 }
2424
2425                                 if (object && object->deleted
2426                                     && tags.chunkId != 0) {
2427                                         /* Data chunk in a deleted file, throw it away
2428                                          * It's a soft deleted data chunk,
2429                                          * No need to copy this, just forget about it and
2430                                          * fix up the object.
2431                                          */
2432
2433                                         object->nDataChunks--;
2434
2435                                         if (object->nDataChunks <= 0) {
2436                                                 /* remeber to clean up the object */
2437                                                 dev->gcCleanupList[cleanups] =
2438                                                     tags.objectId;
2439                                                 cleanups++;
2440                                         }
2441                                         markNAND = 0;
2442                                 } else if (0
2443                                            /* Todo object && object->deleted && object->nDataChunks == 0 */
2444                                            ) {
2445                                         /* Deleted object header with no data chunks.
2446                                          * Can be discarded and the file deleted.
2447                                          */
2448                                         object->chunkId = 0;
2449                                         yaffs_FreeTnode(object->myDev,
2450                                                         object->variant.
2451                                                         fileVariant.top);
2452                                         object->variant.fileVariant.top = NULL;
2453                                         yaffs_DoGenericObjectDeletion(object);
2454
2455                                 } else if (object) {
2456                                         /* It's either a data chunk in a live file or
2457                                          * an ObjectHeader, so we're interested in it.
2458                                          * NB Need to keep the ObjectHeaders of deleted files
2459                                          * until the whole file has been deleted off
2460                                          */
2461                                         tags.serialNumber++;
2462
2463                                         dev->nGCCopies++;
2464
2465                                         if (tags.chunkId == 0) {
2466                                                 /* It is an object Id,
2467                                                  * We need to nuke the shrinkheader flags first
2468                                                  * We no longer want the shrinkHeader flag since its work is done
2469                                                  * and if it is left in place it will mess up scanning.
2470                                                  * Also, clear out any shadowing stuff
2471                                                  */
2472
2473                                                 yaffs_ObjectHeader *oh;
2474                                                 oh = (yaffs_ObjectHeader *)buffer;
2475                                                 oh->isShrink = 0;
2476                                                 oh->shadowsObject = -1;
2477                                                 tags.extraShadows = 0;
2478                                                 tags.extraIsShrinkHeader = 0;
2479                                         }
2480
2481                                         newChunk =
2482                                             yaffs_WriteNewChunkWithTagsToNAND(dev, buffer, &tags, 1);
2483
2484                                         if (newChunk < 0) {
2485                                                 retVal = YAFFS_FAIL;
2486                                         } else {
2487
2488                                                 /* Ok, now fix up the Tnodes etc. */
2489
2490                                                 if (tags.chunkId == 0) {
2491                                                         /* It's a header */
2492                                                         object->chunkId =  newChunk;
2493                                                         object->serial =   tags.serialNumber;
2494                                                 } else {
2495                                                         /* It's a data chunk */
2496                                                         yaffs_PutChunkIntoFile
2497                                                             (object,
2498                                                              tags.chunkId,
2499                                                              newChunk, 0);
2500                                                 }
2501                                         }
2502                                 }
2503
2504                                 yaffs_DeleteChunk(dev, oldChunk, markNAND, __LINE__);
2505
2506                         }
2507                 }
2508
2509                 yaffs_ReleaseTempBuffer(dev, buffer, __LINE__);
2510
2511
2512                 /* Do any required cleanups */
2513                 for (i = 0; i < cleanups; i++) {
2514                         /* Time to delete the file too */
2515                         object =
2516                             yaffs_FindObjectByNumber(dev,
2517                                                      dev->gcCleanupList[i]);
2518                         if (object) {
2519                                 yaffs_FreeTnode(dev,
2520                                                 object->variant.fileVariant.
2521                                                 top);
2522                                 object->variant.fileVariant.top = NULL;
2523                                 T(YAFFS_TRACE_GC,
2524                                   (TSTR
2525                                    ("yaffs: About to finally delete object %d"
2526                                     TENDSTR), object->objectId));
2527                                 yaffs_DoGenericObjectDeletion(object);
2528                                 object->myDev->nDeletedFiles--;
2529                         }
2530
2531                 }
2532
2533         }
2534
2535         if (chunksBefore >= (chunksAfter = yaffs_GetErasedChunks(dev))) {
2536                 T(YAFFS_TRACE_GC,
2537                   (TSTR
2538                    ("gc did not increase free chunks before %d after %d"
2539                     TENDSTR), chunksBefore, chunksAfter));
2540         }
2541
2542         dev->isDoingGC = 0;
2543
2544         return YAFFS_OK;
2545 }
2546
2547 /* New garbage collector
2548  * If we're very low on erased blocks then we do aggressive garbage collection
2549  * otherwise we do "leasurely" garbage collection.
2550  * Aggressive gc looks further (whole array) and will accept less dirty blocks.
2551  * Passive gc only inspects smaller areas and will only accept more dirty blocks.
2552  *
2553  * The idea is to help clear out space in a more spread-out manner.
2554  * Dunno if it really does anything useful.
2555  */
2556 static int yaffs_CheckGarbageCollection(yaffs_Device * dev)
2557 {
2558         int block;
2559         int aggressive;
2560         int gcOk = YAFFS_OK;
2561         int maxTries = 0;
2562
2563         int checkpointBlockAdjust;
2564
2565         if (dev->isDoingGC) {
2566                 /* Bail out so we don't get recursive gc */
2567                 return YAFFS_OK;
2568         }
2569
2570         /* This loop should pass the first time.
2571          * We'll only see looping here if the erase of the collected block fails.
2572          */
2573
2574         do {
2575                 maxTries++;
2576
2577                 checkpointBlockAdjust = (dev->nCheckpointReservedBlocks - dev->blocksInCheckpoint);
2578                 if(checkpointBlockAdjust < 0)
2579                         checkpointBlockAdjust = 0;
2580
2581                 if (dev->nErasedBlocks < (dev->nReservedBlocks + checkpointBlockAdjust)) {
2582                         /* We need a block soon...*/
2583                         aggressive = 1;
2584                 } else {
2585                         /* We're in no hurry */
2586                         aggressive = 0;
2587                 }
2588
2589                 block = yaffs_FindBlockForGarbageCollection(dev, aggressive);
2590
2591                 if (block > 0) {
2592                         dev->garbageCollections++;
2593                         if (!aggressive) {
2594                                 dev->passiveGarbageCollections++;
2595                         }
2596
2597                         T(YAFFS_TRACE_GC,
2598                           (TSTR
2599                            ("yaffs: GC erasedBlocks %d aggressive %d" TENDSTR),
2600                            dev->nErasedBlocks, aggressive));
2601
2602                         gcOk = yaffs_GarbageCollectBlock(dev, block);
2603                 }
2604
2605                 if (dev->nErasedBlocks < (dev->nReservedBlocks) && block > 0) {
2606                         T(YAFFS_TRACE_GC,
2607                           (TSTR
2608                            ("yaffs: GC !!!no reclaim!!! erasedBlocks %d after try %d block %d"
2609                             TENDSTR), dev->nErasedBlocks, maxTries, block));
2610                 }
2611         } while ((dev->nErasedBlocks < dev->nReservedBlocks) && (block > 0)
2612                  && (maxTries < 2));
2613
2614         return aggressive ? gcOk : YAFFS_OK;
2615 }
2616
2617 /*-------------------------  TAGS --------------------------------*/
2618
2619 static int yaffs_TagsMatch(const yaffs_ExtendedTags * tags, int objectId,
2620                            int chunkInObject)
2621 {
2622         return (tags->chunkId == chunkInObject &&
2623                 tags->objectId == objectId && !tags->chunkDeleted) ? 1 : 0;
2624
2625 }
2626
2627
2628 /*-------------------- Data file manipulation -----------------*/
2629
2630 static int yaffs_FindChunkInFile(yaffs_Object * in, int chunkInInode,
2631                                  yaffs_ExtendedTags * tags)
2632 {
2633         /*Get the Tnode, then get the level 0 offset chunk offset */
2634         yaffs_Tnode *tn;
2635         int theChunk = -1;
2636         yaffs_ExtendedTags localTags;
2637         int retVal = -1;
2638
2639         yaffs_Device *dev = in->myDev;
2640
2641         if (!tags) {
2642                 /* Passed a NULL, so use our own tags space */
2643                 tags = &localTags;
2644         }
2645
2646         tn = yaffs_FindLevel0Tnode(dev, &in->variant.fileVariant, chunkInInode);
2647
2648         if (tn) {
2649                 theChunk = yaffs_GetChunkGroupBase(dev,tn,chunkInInode);
2650
2651                 retVal =
2652                     yaffs_FindChunkInGroup(dev, theChunk, tags, in->objectId,
2653                                            chunkInInode);
2654         }
2655         return retVal;
2656 }
2657
2658 static int yaffs_FindAndDeleteChunkInFile(yaffs_Object * in, int chunkInInode,
2659                                           yaffs_ExtendedTags * tags)
2660 {
2661         /* Get the Tnode, then get the level 0 offset chunk offset */
2662         yaffs_Tnode *tn;
2663         int theChunk = -1;
2664         yaffs_ExtendedTags localTags;
2665
2666         yaffs_Device *dev = in->myDev;
2667         int retVal = -1;
2668
2669         if (!tags) {
2670                 /* Passed a NULL, so use our own tags space */
2671                 tags = &localTags;
2672         }
2673
2674         tn = yaffs_FindLevel0Tnode(dev, &in->variant.fileVariant, chunkInInode);
2675
2676         if (tn) {
2677
2678                 theChunk = yaffs_GetChunkGroupBase(dev,tn,chunkInInode);
2679
2680                 retVal =
2681                     yaffs_FindChunkInGroup(dev, theChunk, tags, in->objectId,
2682                                            chunkInInode);
2683
2684                 /* Delete the entry in the filestructure (if found) */
2685                 if (retVal != -1) {
2686                         yaffs_PutLevel0Tnode(dev,tn,chunkInInode,0);
2687                 }
2688         } else {
2689                 /*T(("No level 0 found for %d\n", chunkInInode)); */
2690         }
2691
2692         if (retVal == -1) {
2693                 /* T(("Could not find %d to delete\n",chunkInInode)); */
2694         }
2695         return retVal;
2696 }
2697
2698 #ifdef YAFFS_PARANOID
2699
2700 static int yaffs_CheckFileSanity(yaffs_Object * in)
2701 {
2702         int chunk;
2703         int nChunks;
2704         int fSize;
2705         int failed = 0;
2706         int objId;
2707         yaffs_Tnode *tn;
2708         yaffs_Tags localTags;
2709         yaffs_Tags *tags = &localTags;
2710         int theChunk;
2711         int chunkDeleted;
2712
2713         if (in->variantType != YAFFS_OBJECT_TYPE_FILE) {
2714                 /* T(("Object not a file\n")); */
2715                 return YAFFS_FAIL;
2716         }
2717
2718         objId = in->objectId;
2719         fSize = in->variant.fileVariant.fileSize;
2720         nChunks =
2721             (fSize + in->myDev->nDataBytesPerChunk - 1) / in->myDev->nDataBytesPerChunk;
2722
2723         for (chunk = 1; chunk <= nChunks; chunk++) {
2724                 tn = yaffs_FindLevel0Tnode(in->myDev, &in->variant.fileVariant,
2725                                            chunk);
2726
2727                 if (tn) {
2728
2729                         theChunk = yaffs_GetChunkGroupBase(dev,tn,chunk);
2730
2731                         if (yaffs_CheckChunkBits
2732                             (dev, theChunk / dev->nChunksPerBlock,
2733                              theChunk % dev->nChunksPerBlock)) {
2734
2735                                 yaffs_ReadChunkTagsFromNAND(in->myDev, theChunk,
2736                                                             tags,
2737                                                             &chunkDeleted);
2738                                 if (yaffs_TagsMatch
2739                                     (tags, in->objectId, chunk, chunkDeleted)) {
2740                                         /* found it; */
2741
2742                                 }
2743                         } else {
2744
2745                                 failed = 1;
2746                         }
2747
2748                 } else {
2749                         /* T(("No level 0 found for %d\n", chunk)); */
2750                 }
2751         }
2752
2753         return failed ? YAFFS_FAIL : YAFFS_OK;
2754 }
2755
2756 #endif
2757
2758 static int yaffs_PutChunkIntoFile(yaffs_Object * in, int chunkInInode,
2759                                   int chunkInNAND, int inScan)
2760 {
2761         /* NB inScan is zero unless scanning.
2762          * For forward scanning, inScan is > 0;
2763          * for backward scanning inScan is < 0
2764          */
2765
2766         yaffs_Tnode *tn;
2767         yaffs_Device *dev = in->myDev;
2768         int existingChunk;
2769         yaffs_ExtendedTags existingTags;
2770         yaffs_ExtendedTags newTags;
2771         unsigned existingSerial, newSerial;
2772
2773         if (in->variantType != YAFFS_OBJECT_TYPE_FILE) {
2774                 /* Just ignore an attempt at putting a chunk into a non-file during scanning
2775                  * If it is not during Scanning then something went wrong!
2776                  */
2777                 if (!inScan) {
2778                         T(YAFFS_TRACE_ERROR,
2779                           (TSTR
2780                            ("yaffs tragedy:attempt to put data chunk into a non-file"
2781                             TENDSTR)));
2782                         YBUG();
2783                 }
2784
2785                 yaffs_DeleteChunk(dev, chunkInNAND, 1, __LINE__);
2786                 return YAFFS_OK;
2787         }
2788
2789         tn = yaffs_AddOrFindLevel0Tnode(dev,
2790                                         &in->variant.fileVariant,
2791                                         chunkInInode,
2792                                         NULL);
2793         if (!tn) {
2794                 return YAFFS_FAIL;
2795         }
2796
2797         existingChunk = yaffs_GetChunkGroupBase(dev,tn,chunkInInode);
2798
2799         if (inScan != 0) {
2800                 /* If we're scanning then we need to test for duplicates
2801                  * NB This does not need to be efficient since it should only ever
2802                  * happen when the power fails during a write, then only one
2803                  * chunk should ever be affected.
2804                  *
2805                  * Correction for YAFFS2: This could happen quite a lot and we need to think about efficiency! TODO
2806                  * Update: For backward scanning we don't need to re-read tags so this is quite cheap.
2807                  */
2808
2809                 if (existingChunk != 0) {
2810                         /* NB Right now existing chunk will not be real chunkId if the device >= 32MB
2811                          *    thus we have to do a FindChunkInFile to get the real chunk id.
2812                          *
2813                          * We have a duplicate now we need to decide which one to use:
2814                          *
2815                          * Backwards scanning YAFFS2: The old one is what we use, dump the new one.
2816                          * Forward scanning YAFFS2: The new one is what we use, dump the old one.
2817                          * YAFFS1: Get both sets of tags and compare serial numbers.
2818                          */
2819
2820                         if (inScan > 0) {
2821                                 /* Only do this for forward scanning */
2822                                 yaffs_ReadChunkWithTagsFromNAND(dev,
2823                                                                 chunkInNAND,
2824                                                                 NULL, &newTags);
2825
2826                                 /* Do a proper find */
2827                                 existingChunk =
2828                                     yaffs_FindChunkInFile(in, chunkInInode,
2829                                                           &existingTags);
2830                         }
2831
2832                         if (existingChunk <= 0) {
2833                                 /*Hoosterman - how did this happen? */
2834
2835                                 T(YAFFS_TRACE_ERROR,
2836                                   (TSTR
2837                                    ("yaffs tragedy: existing chunk < 0 in scan"
2838                                     TENDSTR)));
2839
2840                         }
2841
2842                         /* NB The deleted flags should be false, otherwise the chunks will
2843                          * not be loaded during a scan
2844                          */
2845
2846                         newSerial = newTags.serialNumber;
2847                         existingSerial = existingTags.serialNumber;
2848
2849                         if ((inScan > 0) &&
2850                             (in->myDev->isYaffs2 ||
2851                              existingChunk <= 0 ||
2852                              ((existingSerial + 1) & 3) == newSerial)) {
2853                                 /* Forward scanning.
2854                                  * Use new
2855                                  * Delete the old one and drop through to update the tnode
2856                                  */
2857                                 yaffs_DeleteChunk(dev, existingChunk, 1,
2858                                                   __LINE__);
2859                         } else {
2860                                 /* Backward scanning or we want to use the existing one
2861                                  * Use existing.
2862                                  * Delete the new one and return early so that the tnode isn't changed
2863                                  */
2864                                 yaffs_DeleteChunk(dev, chunkInNAND, 1,
2865                                                   __LINE__);
2866                                 return YAFFS_OK;
2867                         }
2868                 }
2869
2870         }
2871
2872         if (existingChunk == 0) {
2873                 in->nDataChunks++;
2874         }
2875
2876         yaffs_PutLevel0Tnode(dev,tn,chunkInInode,chunkInNAND);
2877
2878         return YAFFS_OK;
2879 }
2880
2881 static int yaffs_ReadChunkDataFromObject(yaffs_Object * in, int chunkInInode,
2882                                          __u8 * buffer)
2883 {
2884         int chunkInNAND = yaffs_FindChunkInFile(in, chunkInInode, NULL);
2885
2886         if (chunkInNAND >= 0) {
2887                 return yaffs_ReadChunkWithTagsFromNAND(in->myDev, chunkInNAND,
2888                                                        buffer,NULL);
2889         } else {
2890                 T(YAFFS_TRACE_NANDACCESS,
2891                   (TSTR("Chunk %d not found zero instead" TENDSTR),
2892                    chunkInNAND));
2893                 /* get sane (zero) data if you read a hole */
2894                 memset(buffer, 0, in->myDev->nDataBytesPerChunk);
2895                 return 0;
2896         }
2897
2898 }
2899
2900 void yaffs_DeleteChunk(yaffs_Device * dev, int chunkId, int markNAND, int lyn)
2901 {
2902         int block;
2903         int page;
2904         yaffs_ExtendedTags tags;
2905         yaffs_BlockInfo *bi;
2906
2907         if (chunkId <= 0)
2908                 return;
2909
2910         dev->nDeletions++;
2911         block = chunkId / dev->nChunksPerBlock;
2912         page = chunkId % dev->nChunksPerBlock;
2913
2914         bi = yaffs_GetBlockInfo(dev, block);
2915
2916         T(YAFFS_TRACE_DELETION,
2917           (TSTR("line %d delete of chunk %d" TENDSTR), lyn, chunkId));
2918
2919         if (markNAND &&
2920             bi->blockState != YAFFS_BLOCK_STATE_COLLECTING && !dev->isYaffs2) {
2921
2922                 yaffs_InitialiseTags(&tags);
2923
2924                 tags.chunkDeleted = 1;
2925
2926                 yaffs_WriteChunkWithTagsToNAND(dev, chunkId, NULL, &tags);
2927                 yaffs_HandleUpdateChunk(dev, chunkId, &tags);
2928         } else {
2929                 dev->nUnmarkedDeletions++;
2930         }
2931
2932         /* Pull out of the management area.
2933          * If the whole block became dirty, this will kick off an erasure.
2934          */
2935         if (bi->blockState == YAFFS_BLOCK_STATE_ALLOCATING ||
2936             bi->blockState == YAFFS_BLOCK_STATE_FULL ||
2937             bi->blockState == YAFFS_BLOCK_STATE_NEEDS_SCANNING ||
2938             bi->blockState == YAFFS_BLOCK_STATE_COLLECTING) {
2939                 dev->nFreeChunks++;
2940
2941                 yaffs_ClearChunkBit(dev, block, page);
2942
2943                 bi->pagesInUse--;
2944
2945                 if (bi->pagesInUse == 0 &&
2946                     !bi->hasShrinkHeader &&
2947                     bi->blockState != YAFFS_BLOCK_STATE_ALLOCATING &&
2948                     bi->blockState != YAFFS_BLOCK_STATE_NEEDS_SCANNING) {
2949                         yaffs_BlockBecameDirty(dev, block);
2950                 }
2951
2952         } else {
2953                 /* T(("Bad news deleting chunk %d\n",chunkId)); */
2954         }
2955
2956 }
2957
2958 static int yaffs_WriteChunkDataToObject(yaffs_Object * in, int chunkInInode,
2959                                         const __u8 * buffer, int nBytes,
2960                                         int useReserve)
2961 {
2962         /* Find old chunk Need to do this to get serial number
2963          * Write new one and patch into tree.
2964          * Invalidate old tags.
2965          */
2966
2967         int prevChunkId;
2968         yaffs_ExtendedTags prevTags;
2969
2970         int newChunkId;
2971         yaffs_ExtendedTags newTags;
2972
2973         yaffs_Device *dev = in->myDev;
2974
2975         yaffs_CheckGarbageCollection(dev);
2976
2977         /* Get the previous chunk at this location in the file if it exists */
2978         prevChunkId = yaffs_FindChunkInFile(in, chunkInInode, &prevTags);
2979
2980         /* Set up new tags */
2981         yaffs_InitialiseTags(&newTags);
2982
2983         newTags.chunkId = chunkInInode;
2984         newTags.objectId = in->objectId;
2985         newTags.serialNumber =
2986             (prevChunkId >= 0) ? prevTags.serialNumber + 1 : 1;
2987         newTags.byteCount = nBytes;
2988
2989         newChunkId =
2990             yaffs_WriteNewChunkWithTagsToNAND(dev, buffer, &newTags,
2991                                               useReserve);
2992
2993         if (newChunkId >= 0) {
2994                 yaffs_PutChunkIntoFile(in, chunkInInode, newChunkId, 0);
2995
2996                 if (prevChunkId >= 0) {
2997                         yaffs_DeleteChunk(dev, prevChunkId, 1, __LINE__);
2998
2999                 }
3000
3001                 yaffs_CheckFileSanity(in);
3002         }
3003         return newChunkId;
3004
3005 }
3006
3007 /* UpdateObjectHeader updates the header on NAND for an object.
3008  * If name is not NULL, then that new name is used.
3009  */
3010 int yaffs_UpdateObjectHeader(yaffs_Object * in, const YCHAR * name, int force,
3011                              int isShrink, int shadows)
3012 {
3013
3014         yaffs_BlockInfo *bi;
3015
3016         yaffs_Device *dev = in->myDev;
3017
3018         int prevChunkId;
3019         int retVal = 0;
3020         int result = 0;
3021
3022         int newChunkId;
3023         yaffs_ExtendedTags newTags;
3024
3025         __u8 *buffer = NULL;
3026         YCHAR oldName[YAFFS_MAX_NAME_LENGTH + 1];
3027
3028         yaffs_ObjectHeader *oh = NULL;
3029
3030         if (!in->fake || force) {
3031
3032                 yaffs_CheckGarbageCollection(dev);
3033
3034                 buffer = yaffs_GetTempBuffer(in->myDev, __LINE__);
3035                 oh = (yaffs_ObjectHeader *) buffer;
3036
3037                 prevChunkId = in->chunkId;
3038
3039                 if (prevChunkId >= 0) {
3040                         result = yaffs_ReadChunkWithTagsFromNAND(dev, prevChunkId,
3041                                                         buffer, NULL);
3042                         memcpy(oldName, oh->name, sizeof(oh->name));
3043                 }
3044
3045                 memset(buffer, 0xFF, dev->nDataBytesPerChunk);
3046
3047                 oh->type = in->variantType;
3048                 oh->yst_mode = in->yst_mode;
3049                 oh->shadowsObject = shadows;
3050
3051 #ifdef CONFIG_YAFFS_WINCE
3052                 oh->win_atime[0] = in->win_atime[0];
3053                 oh->win_ctime[0] = in->win_ctime[0];
3054                 oh->win_mtime[0] = in->win_mtime[0];
3055                 oh->win_atime[1] = in->win_atime[1];
3056                 oh->win_ctime[1] = in->win_ctime[1];
3057                 oh->win_mtime[1] = in->win_mtime[1];
3058 #else
3059                 oh->yst_uid = in->yst_uid;
3060                 oh->yst_gid = in->yst_gid;
3061                 oh->yst_atime = in->yst_atime;
3062                 oh->yst_mtime = in->yst_mtime;
3063                 oh->yst_ctime = in->yst_ctime;
3064                 oh->yst_rdev = in->yst_rdev;
3065 #endif
3066                 if (in->parent) {
3067                         oh->parentObjectId = in->parent->objectId;
3068                 } else {
3069                         oh->parentObjectId = 0;
3070                 }
3071
3072                 if (name && *name) {
3073                         memset(oh->name, 0, sizeof(oh->name));
3074                         yaffs_strncpy(oh->name, name, YAFFS_MAX_NAME_LENGTH);
3075                 } else if (prevChunkId) {
3076                         memcpy(oh->name, oldName, sizeof(oh->name));
3077                 } else {
3078                         memset(oh->name, 0, sizeof(oh->name));
3079                 }
3080
3081                 oh->isShrink = isShrink;
3082
3083                 switch (in->variantType) {
3084                 case YAFFS_OBJECT_TYPE_UNKNOWN:
3085                         /* Should not happen */
3086                         break;
3087                 case YAFFS_OBJECT_TYPE_FILE:
3088                         oh->fileSize =
3089                             (oh->parentObjectId == YAFFS_OBJECTID_DELETED
3090                              || oh->parentObjectId ==
3091                              YAFFS_OBJECTID_UNLINKED) ? 0 : in->variant.
3092                             fileVariant.fileSize;
3093                         break;
3094                 case YAFFS_OBJECT_TYPE_HARDLINK:
3095                         oh->equivalentObjectId =
3096                             in->variant.hardLinkVariant.equivalentObjectId;
3097                         break;
3098                 case YAFFS_OBJECT_TYPE_SPECIAL:
3099                         /* Do nothing */
3100                         break;
3101                 case YAFFS_OBJECT_TYPE_DIRECTORY:
3102                         /* Do nothing */
3103                         break;
3104                 case YAFFS_OBJECT_TYPE_SYMLINK:
3105                         yaffs_strncpy(oh->alias,
3106                                       in->variant.symLinkVariant.alias,
3107                                       YAFFS_MAX_ALIAS_LENGTH);
3108                         oh->alias[YAFFS_MAX_ALIAS_LENGTH] = 0;
3109                         break;
3110                 }
3111
3112                 /* Tags */
3113                 yaffs_InitialiseTags(&newTags);
3114                 in->serial++;
3115                 newTags.chunkId = 0;
3116                 newTags.objectId = in->objectId;
3117                 newTags.serialNumber = in->serial;
3118
3119                 /* Add extra info for file header */
3120
3121                 newTags.extraHeaderInfoAvailable = 1;
3122                 newTags.extraParentObjectId = oh->parentObjectId;
3123                 newTags.extraFileLength = oh->fileSize;
3124                 newTags.extraIsShrinkHeader = oh->isShrink;
3125                 newTags.extraEquivalentObjectId = oh->equivalentObjectId;
3126                 newTags.extraShadows = (oh->shadowsObject > 0) ? 1 : 0;
3127                 newTags.extraObjectType = in->variantType;
3128
3129                 /* Create new chunk in NAND */
3130                 newChunkId =
3131                     yaffs_WriteNewChunkWithTagsToNAND(dev, buffer, &newTags,
3132                                                       (prevChunkId >= 0) ? 1 : 0);
3133
3134                 if (newChunkId >= 0) {
3135
3136                         in->chunkId = newChunkId;
3137
3138                         if (prevChunkId >= 0) {
3139                                 yaffs_DeleteChunk(dev, prevChunkId, 1,
3140                                                   __LINE__);
3141                         }
3142
3143                         if(!yaffs_ObjectHasCachedWriteData(in))
3144                                 in->dirty = 0;
3145
3146                         /* If this was a shrink, then mark the block that the chunk lives on */
3147                         if (isShrink) {
3148                                 bi = yaffs_GetBlockInfo(in->myDev,
3149                                                         newChunkId /in->myDev-> nChunksPerBlock);
3150                                 bi->hasShrinkHeader = 1;
3151                         }
3152
3153                 }
3154
3155                 retVal = newChunkId;
3156
3157         }
3158
3159         if (buffer)
3160                 yaffs_ReleaseTempBuffer(dev, buffer, __LINE__);
3161
3162         return retVal;
3163 }
3164
3165 /*------------------------ Short Operations Cache ----------------------------------------
3166  *   In many situations where there is no high level buffering (eg WinCE) a lot of
3167  *   reads might be short sequential reads, and a lot of writes may be short
3168  *   sequential writes. eg. scanning/writing a jpeg file.
3169  *   In these cases, a short read/write cache can provide a huge perfomance benefit
3170  *   with dumb-as-a-rock code.
3171  *   In Linux, the page cache provides read buffering aand the short op cache provides write
3172  *   buffering.
3173  *
3174  *   There are a limited number (~10) of cache chunks per device so that we don't
3175  *   need a very intelligent search.
3176  */
3177
3178 static int yaffs_ObjectHasCachedWriteData(yaffs_Object *obj)
3179 {
3180         yaffs_Device *dev = obj->myDev;
3181         int i;
3182         yaffs_ChunkCache *cache;
3183         int nCaches = obj->myDev->nShortOpCaches;
3184
3185         for(i = 0; i < nCaches; i++){
3186                 cache = &dev->srCache[i];
3187                 if (cache->object == obj &&
3188                     cache->dirty)
3189                         return 1;
3190         }
3191
3192         return 0;
3193 }
3194
3195
3196 static void yaffs_FlushFilesChunkCache(yaffs_Object * obj)
3197 {
3198         yaffs_Device *dev = obj->myDev;
3199         int lowest = -99;       /* Stop compiler whining. */
3200         int i;
3201         yaffs_ChunkCache *cache;
3202         int chunkWritten = 0;
3203         int nCaches = obj->myDev->nShortOpCaches;
3204
3205         if (nCaches > 0) {
3206                 do {
3207                         cache = NULL;
3208
3209                         /* Find the dirty cache for this object with the lowest chunk id. */
3210                         for (i = 0; i < nCaches; i++) {
3211                                 if (dev->srCache[i].object == obj &&
3212                                     dev->srCache[i].dirty) {
3213                                         if (!cache
3214                                             || dev->srCache[i].chunkId <
3215                                             lowest) {
3216                                                 cache = &dev->srCache[i];
3217                                                 lowest = cache->chunkId;
3218                                         }
3219                                 }
3220                         }
3221
3222                         if (cache && !cache->locked) {
3223                                 /* Write it out and free it up */
3224
3225                                 chunkWritten =
3226                                     yaffs_WriteChunkDataToObject(cache->object,
3227                                                                  cache->chunkId,
3228                                                                  cache->data,
3229                                                                  cache->nBytes,
3230                                                                  1);
3231                                 cache->dirty = 0;
3232                                 cache->object = NULL;
3233                         }
3234
3235                 } while (cache && chunkWritten > 0);
3236
3237                 if (cache) {
3238                         /* Hoosterman, disk full while writing cache out. */
3239                         T(YAFFS_TRACE_ERROR,
3240                           (TSTR("yaffs tragedy: no space during cache write" TENDSTR)));
3241
3242                 }
3243         }
3244
3245 }
3246
3247 /*yaffs_FlushEntireDeviceCache(dev)
3248  *
3249  *
3250  */
3251
3252 void yaffs_FlushEntireDeviceCache(yaffs_Device *dev)
3253 {
3254         yaffs_Object *obj;
3255         int nCaches = dev->nShortOpCaches;
3256         int i;
3257
3258         /* Find a dirty object in the cache and flush it...
3259          * until there are no further dirty objects.
3260          */
3261         do {
3262                 obj = NULL;
3263                 for( i = 0; i < nCaches && !obj; i++) {
3264                         if (dev->srCache[i].object &&
3265                             dev->srCache[i].dirty)
3266                                 obj = dev->srCache[i].object;
3267
3268                 }
3269                 if(obj)
3270                         yaffs_FlushFilesChunkCache(obj);
3271
3272         } while(obj);
3273
3274 }
3275
3276
3277 /* Grab us a cache chunk for use.
3278  * First look for an empty one.
3279  * Then look for the least recently used non-dirty one.
3280  * Then look for the least recently used dirty one...., flush and look again.
3281  */
3282 static yaffs_ChunkCache *yaffs_GrabChunkCacheWorker(yaffs_Device * dev)
3283 {
3284         int i;
3285         int usage;
3286         int theOne;
3287
3288         if (dev->nShortOpCaches > 0) {
3289                 for (i = 0; i < dev->nShortOpCaches; i++) {
3290                         if (!dev->srCache[i].object)
3291                                 return &dev->srCache[i];
3292                 }
3293
3294                 return NULL;
3295
3296                 theOne = -1;
3297                 usage = 0;      /* just to stop the compiler grizzling */
3298
3299                 for (i = 0; i < dev->nShortOpCaches; i++) {
3300                         if (!dev->srCache[i].dirty &&
3301                             ((dev->srCache[i].lastUse < usage && theOne >= 0) ||
3302                              theOne < 0)) {
3303                                 usage = dev->srCache[i].lastUse;
3304                                 theOne = i;
3305                         }
3306                 }
3307
3308
3309                 return theOne >= 0 ? &dev->srCache[theOne] : NULL;
3310         } else {
3311                 return NULL;
3312         }
3313
3314 }
3315
3316 static yaffs_ChunkCache *yaffs_GrabChunkCache(yaffs_Device * dev)
3317 {
3318         yaffs_ChunkCache *cache;
3319         yaffs_Object *theObj;
3320         int usage;
3321         int i;
3322         int pushout;
3323
3324         if (dev->nShortOpCaches > 0) {
3325                 /* Try find a non-dirty one... */
3326
3327                 cache = yaffs_GrabChunkCacheWorker(dev);
3328
3329                 if (!cache) {
3330                         /* They were all dirty, find the last recently used object and flush
3331                          * its cache, then  find again.
3332                          * NB what's here is not very accurate, we actually flush the object
3333                          * the last recently used page.
3334                          */
3335
3336                         /* With locking we can't assume we can use entry zero */
3337
3338                         theObj = NULL;
3339                         usage = -1;
3340                         cache = NULL;
3341                         pushout = -1;
3342
3343                         for (i = 0; i < dev->nShortOpCaches; i++) {
3344                                 if (dev->srCache[i].object &&
3345                                     !dev->srCache[i].locked &&
3346                                     (dev->srCache[i].lastUse < usage || !cache))
3347                                 {
3348                                         usage = dev->srCache[i].lastUse;
3349                                         theObj = dev->srCache[i].object;
3350                                         cache = &dev->srCache[i];
3351                                         pushout = i;
3352                                 }
3353                         }
3354
3355                         if (!cache || cache->dirty) {
3356                                 /* Flush and try again */
3357                                 yaffs_FlushFilesChunkCache(theObj);
3358                                 cache = yaffs_GrabChunkCacheWorker(dev);
3359                         }
3360
3361                 }
3362                 return cache;
3363         } else
3364                 return NULL;
3365
3366 }
3367
3368 /* Find a cached chunk */
3369 static yaffs_ChunkCache *yaffs_FindChunkCache(const yaffs_Object * obj,
3370                                               int chunkId)
3371 {
3372         yaffs_Device *dev = obj->myDev;
3373         int i;
3374         if (dev->nShortOpCaches > 0) {
3375                 for (i = 0; i < dev->nShortOpCaches; i++) {
3376                         if (dev->srCache[i].object == obj &&
3377                             dev->srCache[i].chunkId == chunkId) {
3378                                 dev->cacheHits++;
3379
3380                                 return &dev->srCache[i];
3381                         }
3382                 }
3383         }
3384         return NULL;
3385 }
3386
3387 /* Mark the chunk for the least recently used algorithym */
3388 static void yaffs_UseChunkCache(yaffs_Device * dev, yaffs_ChunkCache * cache,
3389                                 int isAWrite)
3390 {
3391
3392         if (dev->nShortOpCaches > 0) {
3393                 if (dev->srLastUse < 0 || dev->srLastUse > 100000000) {
3394                         /* Reset the cache usages */
3395                         int i;
3396                         for (i = 1; i < dev->nShortOpCaches; i++) {
3397                                 dev->srCache[i].lastUse = 0;
3398                         }
3399                         dev->srLastUse = 0;
3400                 }
3401
3402                 dev->srLastUse++;
3403
3404                 cache->lastUse = dev->srLastUse;
3405
3406                 if (isAWrite) {
3407                         cache->dirty = 1;
3408                 }
3409         }
3410 }
3411
3412 /* Invalidate a single cache page.
3413  * Do this when a whole page gets written,
3414  * ie the short cache for this page is no longer valid.
3415  */
3416 static void yaffs_InvalidateChunkCache(yaffs_Object * object, int chunkId)
3417 {
3418         if (object->myDev->nShortOpCaches > 0) {
3419                 yaffs_ChunkCache *cache = yaffs_FindChunkCache(object, chunkId);
3420
3421                 if (cache) {
3422                         cache->object = NULL;
3423                 }
3424         }
3425 }
3426
3427 /* Invalidate all the cache pages associated with this object
3428  * Do this whenever ther file is deleted or resized.
3429  */
3430 static void yaffs_InvalidateWholeChunkCache(yaffs_Object * in)
3431 {
3432         int i;
3433         yaffs_Device *dev = in->myDev;
3434
3435         if (dev->nShortOpCaches > 0) {
3436                 /* Invalidate it. */
3437                 for (i = 0; i < dev->nShortOpCaches; i++) {
3438                         if (dev->srCache[i].object == in) {
3439                                 dev->srCache[i].object = NULL;
3440                         }
3441                 }
3442         }
3443 }
3444
3445 /*--------------------- Checkpointing --------------------*/
3446
3447
3448 static int yaffs_WriteCheckpointValidityMarker(yaffs_Device *dev,int head)
3449 {
3450         yaffs_CheckpointValidity cp;
3451         cp.structType = sizeof(cp);
3452         cp.magic = YAFFS_MAGIC;
3453         cp.version = YAFFS_CHECKPOINT_VERSION;
3454         cp.head = (head) ? 1 : 0;
3455
3456         return (yaffs_CheckpointWrite(dev,&cp,sizeof(cp)) == sizeof(cp))?
3457                 1 : 0;
3458 }
3459
3460 static int yaffs_ReadCheckpointValidityMarker(yaffs_Device *dev, int head)
3461 {
3462         yaffs_CheckpointValidity cp;
3463         int ok;
3464
3465         ok = (yaffs_CheckpointRead(dev,&cp,sizeof(cp)) == sizeof(cp));
3466
3467         if(ok)
3468                 ok = (cp.structType == sizeof(cp)) &&
3469                      (cp.magic == YAFFS_MAGIC) &&
3470                      (cp.version == YAFFS_CHECKPOINT_VERSION) &&
3471                      (cp.head == ((head) ? 1 : 0));
3472         return ok ? 1 : 0;
3473 }
3474
3475 static void yaffs_DeviceToCheckpointDevice(yaffs_CheckpointDevice *cp,
3476                                            yaffs_Device *dev)
3477 {
3478         cp->nErasedBlocks = dev->nErasedBlocks;
3479         cp->allocationBlock = dev->allocationBlock;
3480         cp->allocationPage = dev->allocationPage;
3481         cp->nFreeChunks = dev->nFreeChunks;
3482
3483         cp->nDeletedFiles = dev->nDeletedFiles;
3484         cp->nUnlinkedFiles = dev->nUnlinkedFiles;
3485         cp->nBackgroundDeletions = dev->nBackgroundDeletions;
3486         cp->sequenceNumber = dev->sequenceNumber;
3487         cp->oldestDirtySequence = dev->oldestDirtySequence;
3488
3489 }
3490
3491 static void yaffs_CheckpointDeviceToDevice(yaffs_Device *dev,
3492                                            yaffs_CheckpointDevice *cp)
3493 {
3494         dev->nErasedBlocks = cp->nErasedBlocks;
3495         dev->allocationBlock = cp->allocationBlock;
3496         dev->allocationPage = cp->allocationPage;
3497         dev->nFreeChunks = cp->nFreeChunks;
3498
3499         dev->nDeletedFiles = cp->nDeletedFiles;
3500         dev->nUnlinkedFiles = cp->nUnlinkedFiles;
3501         dev->nBackgroundDeletions = cp->nBackgroundDeletions;
3502         dev->sequenceNumber = cp->sequenceNumber;
3503         dev->oldestDirtySequence = cp->oldestDirtySequence;
3504 }
3505
3506
3507 static int yaffs_WriteCheckpointDevice(yaffs_Device *dev)
3508 {
3509         yaffs_CheckpointDevice cp;
3510         __u32 nBytes;
3511         __u32 nBlocks = (dev->internalEndBlock - dev->internalStartBlock + 1);
3512
3513         int ok;
3514
3515         /* Write device runtime values*/
3516         yaffs_DeviceToCheckpointDevice(&cp,dev);
3517         cp.structType = sizeof(cp);
3518
3519         ok = (yaffs_CheckpointWrite(dev,&cp,sizeof(cp)) == sizeof(cp));
3520
3521         /* Write block info */
3522         if(ok) {
3523                 nBytes = nBlocks * sizeof(yaffs_BlockInfo);
3524                 ok = (yaffs_CheckpointWrite(dev,dev->blockInfo,nBytes) == nBytes);
3525         }
3526
3527         /* Write chunk bits */
3528         if(ok) {
3529                 nBytes = nBlocks * dev->chunkBitmapStride;
3530                 ok = (yaffs_CheckpointWrite(dev,dev->chunkBits,nBytes) == nBytes);
3531         }
3532         return   ok ? 1 : 0;
3533
3534 }
3535
3536 static int yaffs_ReadCheckpointDevice(yaffs_Device *dev)
3537 {
3538         yaffs_CheckpointDevice cp;
3539         __u32 nBytes;
3540         __u32 nBlocks = (dev->internalEndBlock - dev->internalStartBlock + 1);
3541
3542         int ok;
3543
3544         ok = (yaffs_CheckpointRead(dev,&cp,sizeof(cp)) == sizeof(cp));
3545         if(!ok)
3546                 return 0;
3547
3548         if(cp.structType != sizeof(cp))
3549                 return 0;
3550
3551
3552         yaffs_CheckpointDeviceToDevice(dev,&cp);
3553
3554         nBytes = nBlocks * sizeof(yaffs_BlockInfo);
3555
3556         ok = (yaffs_CheckpointRead(dev,dev->blockInfo,nBytes) == nBytes);
3557
3558         if(!ok)
3559                 return 0;
3560         nBytes = nBlocks * dev->chunkBitmapStride;
3561
3562         ok = (yaffs_CheckpointRead(dev,dev->chunkBits,nBytes) == nBytes);
3563
3564         return ok ? 1 : 0;
3565 }
3566
3567 static void yaffs_ObjectToCheckpointObject(yaffs_CheckpointObject *cp,
3568                                            yaffs_Object *obj)
3569 {
3570
3571         cp->objectId = obj->objectId;
3572         cp->parentId = (obj->parent) ? obj->parent->objectId : 0;
3573         cp->chunkId = obj->chunkId;
3574         cp->variantType = obj->variantType;
3575         cp->deleted = obj->deleted;
3576         cp->softDeleted = obj->softDeleted;
3577         cp->unlinked = obj->unlinked;
3578         cp->fake = obj->fake;
3579         cp->renameAllowed = obj->renameAllowed;
3580         cp->unlinkAllowed = obj->unlinkAllowed;
3581         cp->serial = obj->serial;
3582         cp->nDataChunks = obj->nDataChunks;
3583
3584         if(obj->variantType == YAFFS_OBJECT_TYPE_FILE)
3585                 cp->fileSizeOrEquivalentObjectId = obj->variant.fileVariant.fileSize;
3586         else if(obj->variantType == YAFFS_OBJECT_TYPE_HARDLINK)
3587                 cp->fileSizeOrEquivalentObjectId = obj->variant.hardLinkVariant.equivalentObjectId;
3588 }
3589
3590 static void yaffs_CheckpointObjectToObject( yaffs_Object *obj,yaffs_CheckpointObject *cp)
3591 {
3592
3593         yaffs_Object *parent;
3594
3595         obj->objectId = cp->objectId;
3596
3597         if(cp->parentId)
3598                 parent = yaffs_FindOrCreateObjectByNumber(
3599                                         obj->myDev,
3600                                         cp->parentId,
3601                                         YAFFS_OBJECT_TYPE_DIRECTORY);
3602         else
3603                 parent = NULL;
3604
3605         if(parent)
3606                 yaffs_AddObjectToDirectory(parent, obj);
3607
3608         obj->chunkId = cp->chunkId;
3609         obj->variantType = cp->variantType;
3610         obj->deleted = cp->deleted;
3611         obj->softDeleted = cp->softDeleted;
3612         obj->unlinked = cp->unlinked;
3613         obj->fake = cp->fake;
3614         obj->renameAllowed = cp->renameAllowed;
3615         obj->unlinkAllowed = cp->unlinkAllowed;
3616         obj->serial = cp->serial;
3617         obj->nDataChunks = cp->nDataChunks;
3618
3619         if(obj->variantType == YAFFS_OBJECT_TYPE_FILE)
3620                 obj->variant.fileVariant.fileSize = cp->fileSizeOrEquivalentObjectId;
3621         else if(obj->variantType == YAFFS_OBJECT_TYPE_HARDLINK)
3622                 obj->variant.hardLinkVariant.equivalentObjectId = cp->fileSizeOrEquivalentObjectId;
3623
3624         if(obj->objectId >= YAFFS_NOBJECT_BUCKETS)
3625                 obj->lazyLoaded = 1;
3626 }
3627
3628
3629
3630 static int yaffs_CheckpointTnodeWorker(yaffs_Object * in, yaffs_Tnode * tn,
3631                                         __u32 level, int chunkOffset)
3632 {
3633         int i;
3634         yaffs_Device *dev = in->myDev;
3635         int ok = 1;
3636         int nTnodeBytes = (dev->tnodeWidth * YAFFS_NTNODES_LEVEL0)/8;
3637
3638         if (tn) {
3639                 if (level > 0) {
3640
3641                         for (i = 0; i < YAFFS_NTNODES_INTERNAL && ok; i++){
3642                                 if (tn->internal[i]) {
3643                                         ok = yaffs_CheckpointTnodeWorker(in,
3644                                                         tn->internal[i],
3645                                                         level - 1,
3646                                                         (chunkOffset<<YAFFS_TNODES_INTERNAL_BITS) + i);
3647                                 }
3648                         }
3649                 } else if (level == 0) {
3650                         __u32 baseOffset = chunkOffset <<  YAFFS_TNODES_LEVEL0_BITS;
3651                         /* printf("write tnode at %d\n",baseOffset); */
3652                         ok = (yaffs_CheckpointWrite(dev,&baseOffset,sizeof(baseOffset)) == sizeof(baseOffset));
3653                         if(ok)
3654                                 ok = (yaffs_CheckpointWrite(dev,tn,nTnodeBytes) == nTnodeBytes);
3655                 }
3656         }
3657
3658         return ok;
3659
3660 }
3661
3662 static int yaffs_WriteCheckpointTnodes(yaffs_Object *obj)
3663 {
3664         __u32 endMarker = ~0;
3665         int ok = 1;
3666
3667         if(obj->variantType == YAFFS_OBJECT_TYPE_FILE){
3668                 ok = yaffs_CheckpointTnodeWorker(obj,
3669                                             obj->variant.fileVariant.top,
3670                                             obj->variant.fileVariant.topLevel,
3671                                             0);
3672                 if(ok)
3673                         ok = (yaffs_CheckpointWrite(obj->myDev,&endMarker,sizeof(endMarker)) ==
3674                                 sizeof(endMarker));
3675         }
3676
3677         return ok ? 1 : 0;
3678 }
3679
3680 static int yaffs_ReadCheckpointTnodes(yaffs_Object *obj)
3681 {
3682         __u32 baseChunk;
3683         int ok = 1;
3684         yaffs_Device *dev = obj->myDev;
3685         yaffs_FileStructure *fileStructPtr = &obj->variant.fileVariant;
3686         yaffs_Tnode *tn;
3687
3688         ok = (yaffs_CheckpointRead(dev,&baseChunk,sizeof(baseChunk)) == sizeof(baseChunk));
3689
3690         while(ok && (~baseChunk)){
3691                 /* Read level 0 tnode */
3692
3693                 /* printf("read  tnode at %d\n",baseChunk); */
3694                 tn = yaffs_GetTnodeRaw(dev);
3695                 if(tn)
3696                         ok = (yaffs_CheckpointRead(dev,tn,(dev->tnodeWidth * YAFFS_NTNODES_LEVEL0)/8) ==
3697                               (dev->tnodeWidth * YAFFS_NTNODES_LEVEL0)/8);
3698                 else
3699                         ok = 0;
3700
3701                 if(tn && ok){
3702                         ok = yaffs_AddOrFindLevel0Tnode(dev,
3703                                                         fileStructPtr,
3704                                                         baseChunk,
3705                                                         tn) ? 1 : 0;
3706                 }
3707
3708                 if(ok)
3709                         ok = (yaffs_CheckpointRead(dev,&baseChunk,sizeof(baseChunk)) == sizeof(baseChunk));
3710
3711         }
3712
3713         return ok ? 1 : 0;
3714 }
3715
3716
3717 static int yaffs_WriteCheckpointObjects(yaffs_Device *dev)
3718 {
3719         yaffs_Object *obj;
3720         yaffs_CheckpointObject cp;
3721         int i;
3722         int ok = 1;
3723         struct list_head *lh;
3724
3725
3726         /* Iterate through the objects in each hash entry,
3727          * dumping them to the checkpointing stream.
3728          */
3729
3730          for(i = 0; ok &&  i <  YAFFS_NOBJECT_BUCKETS; i++){
3731                 list_for_each(lh, &dev->objectBucket[i].list) {
3732                         if (lh) {
3733                                 obj = list_entry(lh, yaffs_Object, hashLink);
3734                                 if (!obj->deferedFree) {
3735                                         yaffs_ObjectToCheckpointObject(&cp,obj);
3736                                         cp.structType = sizeof(cp);
3737
3738                                         T(YAFFS_TRACE_CHECKPOINT,(
3739                                                 TSTR("Checkpoint write object %d parent %d type %d chunk %d obj addr %x" TENDSTR),
3740                                                 cp.objectId,cp.parentId,cp.variantType,cp.chunkId,(unsigned) obj));
3741
3742                                         ok = (yaffs_CheckpointWrite(dev,&cp,sizeof(cp)) == sizeof(cp));
3743
3744                                         if(ok && obj->variantType == YAFFS_OBJECT_TYPE_FILE){
3745                                                 ok = yaffs_WriteCheckpointTnodes(obj);
3746                                         }
3747                                 }
3748                         }
3749                 }
3750          }
3751
3752          /* Dump end of list */
3753         memset(&cp,0xFF,sizeof(yaffs_CheckpointObject));
3754         cp.structType = sizeof(cp);
3755
3756         if(ok)
3757                 ok = (yaffs_CheckpointWrite(dev,&cp,sizeof(cp)) == sizeof(cp));
3758
3759         return ok ? 1 : 0;
3760 }
3761
3762 static int yaffs_ReadCheckpointObjects(yaffs_Device *dev)
3763 {
3764         yaffs_Object *obj;
3765         yaffs_CheckpointObject cp;
3766         int ok = 1;
3767         int done = 0;
3768         yaffs_Object *hardList = NULL;
3769
3770         while(ok && !done) {
3771                 ok = (yaffs_CheckpointRead(dev,&cp,sizeof(cp)) == sizeof(cp));
3772                 if(cp.structType != sizeof(cp)) {
3773                         /* printf("structure parsing failed\n"); */
3774                         ok = 0;
3775                 }
3776
3777                 if(ok && cp.objectId == ~0)
3778                         done = 1;
3779                 else if(ok){
3780                         obj = yaffs_FindOrCreateObjectByNumber(dev,cp.objectId, cp.variantType);
3781                         T(YAFFS_TRACE_CHECKPOINT,(TSTR("Checkpoint read object %d parent %d type %d chunk %d obj addr %x" TENDSTR),
3782                                 cp.objectId,cp.parentId,cp.variantType,cp.chunkId,(unsigned) obj));
3783                         if(obj) {
3784                                 yaffs_CheckpointObjectToObject(obj,&cp);
3785                                 if(obj->variantType == YAFFS_OBJECT_TYPE_FILE) {
3786                                         ok = yaffs_ReadCheckpointTnodes(obj);
3787                                 } else if(obj->variantType == YAFFS_OBJECT_TYPE_HARDLINK) {
3788                                         obj->hardLinks.next =
3789                                                     (struct list_head *)
3790                                                     hardList;
3791                                         hardList = obj;
3792                                 }
3793
3794                         }
3795                 }
3796         }
3797
3798         if(ok)
3799                 yaffs_HardlinkFixup(dev,hardList);
3800
3801         return ok ? 1 : 0;
3802 }
3803
3804 static int yaffs_WriteCheckpointData(yaffs_Device *dev)
3805 {
3806
3807         int ok;
3808
3809         ok = yaffs_CheckpointOpen(dev,1);
3810
3811         if(ok)
3812                 ok = yaffs_WriteCheckpointValidityMarker(dev,1);
3813         if(ok)
3814                 ok = yaffs_WriteCheckpointDevice(dev);
3815         if(ok)
3816                 ok = yaffs_WriteCheckpointObjects(dev);
3817         if(ok)
3818                 ok = yaffs_WriteCheckpointValidityMarker(dev,0);
3819
3820         if(!yaffs_CheckpointClose(dev))
3821                  ok = 0;
3822
3823         if(ok)
3824                 dev->isCheckpointed = 1;
3825          else
3826                 dev->isCheckpointed = 0;
3827
3828         return dev->isCheckpointed;
3829 }
3830
3831 static int yaffs_ReadCheckpointData(yaffs_Device *dev)
3832 {
3833         int ok;
3834
3835         ok = yaffs_CheckpointOpen(dev,0); /* open for read */
3836
3837         if(ok)
3838                 ok = yaffs_ReadCheckpointValidityMarker(dev,1);
3839         if(ok)
3840                 ok = yaffs_ReadCheckpointDevice(dev);
3841         if(ok)
3842                 ok = yaffs_ReadCheckpointObjects(dev);
3843         if(ok)
3844                 ok = yaffs_ReadCheckpointValidityMarker(dev,0);
3845
3846
3847
3848         if(!yaffs_CheckpointClose(dev))
3849                 ok = 0;
3850
3851         if(ok)
3852                 dev->isCheckpointed = 1;
3853          else
3854                 dev->isCheckpointed = 0;
3855
3856         return ok ? 1 : 0;
3857
3858 }
3859
3860 static void yaffs_InvalidateCheckpoint(yaffs_Device *dev)
3861 {
3862         if(dev->isCheckpointed ||
3863            dev->blocksInCheckpoint > 0){
3864                 dev->isCheckpointed = 0;
3865                 yaffs_CheckpointInvalidateStream(dev);
3866                 if(dev->superBlock && dev->markSuperBlockDirty)
3867                         dev->markSuperBlockDirty(dev->superBlock);
3868         }
3869 }
3870
3871
3872 int yaffs_CheckpointSave(yaffs_Device *dev)
3873 {
3874         yaffs_ReportOddballBlocks(dev);
3875         T(YAFFS_TRACE_CHECKPOINT,(TSTR("save entry: isCheckpointed %d"TENDSTR),dev->isCheckpointed));
3876
3877         if(!dev->isCheckpointed)
3878                 yaffs_WriteCheckpointData(dev);
3879
3880         T(YAFFS_TRACE_CHECKPOINT,(TSTR("save exit: isCheckpointed %d"TENDSTR),dev->isCheckpointed));
3881
3882         return dev->isCheckpointed;
3883 }
3884
3885 int yaffs_CheckpointRestore(yaffs_Device *dev)
3886 {
3887         int retval;
3888         T(YAFFS_TRACE_CHECKPOINT,(TSTR("restore entry: isCheckpointed %d"TENDSTR),dev->isCheckpointed));
3889
3890         retval = yaffs_ReadCheckpointData(dev);
3891
3892         T(YAFFS_TRACE_CHECKPOINT,(TSTR("restore exit: isCheckpointed %d"TENDSTR),dev->isCheckpointed));
3893
3894         yaffs_ReportOddballBlocks(dev);
3895
3896         return retval;
3897 }
3898
3899 /*--------------------- File read/write ------------------------
3900  * Read and write have very similar structures.
3901  * In general the read/write has three parts to it
3902  * An incomplete chunk to start with (if the read/write is not chunk-aligned)
3903  * Some complete chunks
3904  * An incomplete chunk to end off with
3905  *
3906  * Curve-balls: the first chunk might also be the last chunk.
3907  */
3908
3909 int yaffs_ReadDataFromFile(yaffs_Object * in, __u8 * buffer, loff_t offset,
3910                            int nBytes)
3911 {
3912
3913         int chunk;
3914         int start;
3915         int nToCopy;
3916         int n = nBytes;
3917         int nDone = 0;
3918         yaffs_ChunkCache *cache;
3919
3920         yaffs_Device *dev;
3921
3922         dev = in->myDev;
3923
3924         while (n > 0) {
3925                 //chunk = offset / dev->nDataBytesPerChunk + 1;
3926                 //start = offset % dev->nDataBytesPerChunk;
3927                 yaffs_AddrToChunk(dev,offset,&chunk,&start);
3928                 chunk++;
3929
3930                 /* OK now check for the curveball where the start and end are in
3931                  * the same chunk.
3932                  */
3933                 if ((start + n) < dev->nDataBytesPerChunk) {
3934                         nToCopy = n;
3935                 } else {
3936                         nToCopy = dev->nDataBytesPerChunk - start;
3937                 }
3938
3939                 cache = yaffs_FindChunkCache(in, chunk);
3940
3941                 /* If the chunk is already in the cache or it is less than a whole chunk
3942                  * then use the cache (if there is caching)
3943                  * else bypass the cache.
3944                  */
3945                 if (cache || nToCopy != dev->nDataBytesPerChunk) {
3946                         if (dev->nShortOpCaches > 0) {
3947
3948                                 /* If we can't find the data in the cache, then load it up. */
3949
3950                                 if (!cache) {
3951                                         cache = yaffs_GrabChunkCache(in->myDev);
3952                                         cache->object = in;
3953                                         cache->chunkId = chunk;
3954                                         cache->dirty = 0;
3955                                         cache->locked = 0;
3956                                         yaffs_ReadChunkDataFromObject(in, chunk,
3957                                                                       cache->
3958                                                                       data);
3959                                         cache->nBytes = 0;
3960                                 }
3961
3962                                 yaffs_UseChunkCache(dev, cache, 0);
3963
3964                                 cache->locked = 1;
3965
3966 #ifdef CONFIG_YAFFS_WINCE
3967                                 yfsd_UnlockYAFFS(TRUE);
3968 #endif
3969                                 memcpy(buffer, &cache->data[start], nToCopy);
3970
3971 #ifdef CONFIG_YAFFS_WINCE
3972                                 yfsd_LockYAFFS(TRUE);
3973 #endif
3974                                 cache->locked = 0;
3975                         } else {
3976                                 /* Read into the local buffer then copy..*/
3977
3978                                 __u8 *localBuffer =
3979                                     yaffs_GetTempBuffer(dev, __LINE__);
3980                                 yaffs_ReadChunkDataFromObject(in, chunk,
3981                                                               localBuffer);
3982 #ifdef CONFIG_YAFFS_WINCE
3983                                 yfsd_UnlockYAFFS(TRUE);
3984 #endif
3985                                 memcpy(buffer, &localBuffer[start], nToCopy);
3986
3987 #ifdef CONFIG_YAFFS_WINCE
3988                                 yfsd_LockYAFFS(TRUE);
3989 #endif
3990                                 yaffs_ReleaseTempBuffer(dev, localBuffer,
3991                                                         __LINE__);
3992                         }
3993
3994                 } else {
3995 #ifdef CONFIG_YAFFS_WINCE
3996                         __u8 *localBuffer = yaffs_GetTempBuffer(dev, __LINE__);
3997
3998                         /* Under WinCE can't do direct transfer. Need to use a local buffer.
3999                          * This is because we otherwise screw up WinCE's memory mapper
4000                          */
4001                         yaffs_ReadChunkDataFromObject(in, chunk, localBuffer);
4002
4003 #ifdef CONFIG_YAFFS_WINCE
4004                         yfsd_UnlockYAFFS(TRUE);
4005 #endif
4006                         memcpy(buffer, localBuffer, dev->nDataBytesPerChunk);
4007
4008 #ifdef CONFIG_YAFFS_WINCE
4009                         yfsd_LockYAFFS(TRUE);
4010                         yaffs_ReleaseTempBuffer(dev, localBuffer, __LINE__);
4011 #endif
4012
4013 #else
4014                         /* A full chunk. Read directly into the supplied buffer. */
4015                         yaffs_ReadChunkDataFromObject(in, chunk, buffer);
4016 #endif
4017                 }
4018
4019                 n -= nToCopy;
4020                 offset += nToCopy;
4021                 buffer += nToCopy;
4022                 nDone += nToCopy;
4023
4024         }
4025
4026         return nDone;
4027 }
4028
4029 int yaffs_WriteDataToFile(yaffs_Object * in, const __u8 * buffer, loff_t offset,
4030                           int nBytes, int writeThrough)
4031 {
4032
4033         int chunk;
4034         int start;
4035         int nToCopy;
4036         int n = nBytes;
4037         int nDone = 0;
4038         int nToWriteBack;
4039         int startOfWrite = offset;
4040         int chunkWritten = 0;
4041         int nBytesRead;
4042
4043         yaffs_Device *dev;
4044
4045         dev = in->myDev;
4046
4047         while (n > 0 && chunkWritten >= 0) {
4048                 //chunk = offset / dev->nDataBytesPerChunk + 1;
4049                 //start = offset % dev->nDataBytesPerChunk;
4050                 yaffs_AddrToChunk(dev,offset,&chunk,&start);
4051                 chunk++;
4052
4053                 /* OK now check for the curveball where the start and end are in
4054                  * the same chunk.
4055                  */
4056
4057                 if ((start + n) < dev->nDataBytesPerChunk) {
4058                         nToCopy = n;
4059
4060                         /* Now folks, to calculate how many bytes to write back....
4061                          * If we're overwriting and not writing to then end of file then
4062                          * we need to write back as much as was there before.
4063                          */
4064
4065                         nBytesRead =
4066                             in->variant.fileVariant.fileSize -
4067                             ((chunk - 1) * dev->nDataBytesPerChunk);
4068
4069                         if (nBytesRead > dev->nDataBytesPerChunk) {
4070                                 nBytesRead = dev->nDataBytesPerChunk;
4071                         }
4072
4073                         nToWriteBack =
4074                             (nBytesRead >
4075                              (start + n)) ? nBytesRead : (start + n);
4076
4077                 } else {
4078                         nToCopy = dev->nDataBytesPerChunk - start;
4079                         nToWriteBack = dev->nDataBytesPerChunk;
4080                 }
4081
4082                 if (nToCopy != dev->nDataBytesPerChunk) {
4083                         /* An incomplete start or end chunk (or maybe both start and end chunk) */
4084                         if (dev->nShortOpCaches > 0) {
4085                                 yaffs_ChunkCache *cache;
4086                                 /* If we can't find the data in the cache, then load the cache */
4087                                 cache = yaffs_FindChunkCache(in, chunk);
4088
4089                                 if (!cache
4090                                     && yaffs_CheckSpaceForAllocation(in->
4091                                                                      myDev)) {
4092                                         cache = yaffs_GrabChunkCache(in->myDev);
4093                                         cache->object = in;
4094                                         cache->chunkId = chunk;
4095                                         cache->dirty = 0;
4096                                         cache->locked = 0;
4097                                         yaffs_ReadChunkDataFromObject(in, chunk,
4098                                                                       cache->
4099                                                                       data);
4100                                 }
4101                                 else if(cache &&
4102                                         !cache->dirty &&
4103                                         !yaffs_CheckSpaceForAllocation(in->myDev)){
4104                                         /* Drop the cache if it was a read cache item and
4105                                          * no space check has been made for it.
4106                                          */
4107                                          cache = NULL;
4108                                 }
4109
4110                                 if (cache) {
4111                                         yaffs_UseChunkCache(dev, cache, 1);
4112                                         cache->locked = 1;
4113 #ifdef CONFIG_YAFFS_WINCE
4114                                         yfsd_UnlockYAFFS(TRUE);
4115 #endif
4116
4117                                         memcpy(&cache->data[start], buffer,
4118                                                nToCopy);
4119
4120 #ifdef CONFIG_YAFFS_WINCE
4121                                         yfsd_LockYAFFS(TRUE);
4122 #endif
4123                                         cache->locked = 0;
4124                                         cache->nBytes = nToWriteBack;
4125
4126                                         if (writeThrough) {
4127                                                 chunkWritten =
4128                                                     yaffs_WriteChunkDataToObject
4129                                                     (cache->object,
4130                                                      cache->chunkId,
4131                                                      cache->data, cache->nBytes,
4132                                                      1);
4133                                                 cache->dirty = 0;
4134                                         }
4135
4136                                 } else {
4137                                         chunkWritten = -1;      /* fail the write */
4138                                 }
4139                         } else {
4140                                 /* An incomplete start or end chunk (or maybe both start and end chunk)
4141                                  * Read into the local buffer then copy, then copy over and write back.
4142                                  */
4143
4144                                 __u8 *localBuffer =
4145                                     yaffs_GetTempBuffer(dev, __LINE__);
4146
4147                                 yaffs_ReadChunkDataFromObject(in, chunk,
4148                                                               localBuffer);
4149
4150 #ifdef CONFIG_YAFFS_WINCE
4151                                 yfsd_UnlockYAFFS(TRUE);
4152 #endif
4153
4154                                 memcpy(&localBuffer[start], buffer, nToCopy);
4155
4156 #ifdef CONFIG_YAFFS_WINCE
4157                                 yfsd_LockYAFFS(TRUE);
4158 #endif
4159                                 chunkWritten =
4160                                     yaffs_WriteChunkDataToObject(in, chunk,
4161                                                                  localBuffer,
4162                                                                  nToWriteBack,
4163                                                                  0);
4164
4165                                 yaffs_ReleaseTempBuffer(dev, localBuffer,
4166                                                         __LINE__);
4167
4168                         }
4169
4170                 } else {
4171
4172 #ifdef CONFIG_YAFFS_WINCE
4173                         /* Under WinCE can't do direct transfer. Need to use a local buffer.
4174                          * This is because we otherwise screw up WinCE's memory mapper
4175                          */
4176                         __u8 *localBuffer = yaffs_GetTempBuffer(dev, __LINE__);
4177 #ifdef CONFIG_YAFFS_WINCE
4178                         yfsd_UnlockYAFFS(TRUE);
4179 #endif
4180                         memcpy(localBuffer, buffer, dev->nDataBytesPerChunk);
4181 #ifdef CONFIG_YAFFS_WINCE
4182                         yfsd_LockYAFFS(TRUE);
4183 #endif
4184                         chunkWritten =
4185                             yaffs_WriteChunkDataToObject(in, chunk, localBuffer,
4186                                                          dev->nDataBytesPerChunk,
4187                                                          0);
4188                         yaffs_ReleaseTempBuffer(dev, localBuffer, __LINE__);
4189 #else
4190                         /* A full chunk. Write directly from the supplied buffer. */
4191                         chunkWritten =
4192                             yaffs_WriteChunkDataToObject(in, chunk, buffer,
4193                                                          dev->nDataBytesPerChunk,
4194                                                          0);
4195 #endif
4196                         /* Since we've overwritten the cached data, we better invalidate it. */
4197                         yaffs_InvalidateChunkCache(in, chunk);
4198                 }
4199
4200                 if (chunkWritten >= 0) {
4201                         n -= nToCopy;
4202                         offset += nToCopy;
4203                         buffer += nToCopy;
4204                         nDone += nToCopy;
4205                 }
4206
4207         }
4208
4209         /* Update file object */
4210
4211         if ((startOfWrite + nDone) > in->variant.fileVariant.fileSize) {
4212                 in->variant.fileVariant.fileSize = (startOfWrite + nDone);
4213         }
4214
4215         in->dirty = 1;
4216
4217         return nDone;
4218 }
4219
4220
4221 /* ---------------------- File resizing stuff ------------------ */
4222
4223 static void yaffs_PruneResizedChunks(yaffs_Object * in, int newSize)
4224 {
4225
4226         yaffs_Device *dev = in->myDev;
4227         int oldFileSize = in->variant.fileVariant.fileSize;
4228
4229         int lastDel = 1 + (oldFileSize - 1) / dev->nDataBytesPerChunk;
4230
4231         int startDel = 1 + (newSize + dev->nDataBytesPerChunk - 1) /
4232             dev->nDataBytesPerChunk;
4233         int i;
4234         int chunkId;
4235
4236         /* Delete backwards so that we don't end up with holes if
4237          * power is lost part-way through the operation.
4238          */
4239         for (i = lastDel; i >= startDel; i--) {
4240                 /* NB this could be optimised somewhat,
4241                  * eg. could retrieve the tags and write them without
4242                  * using yaffs_DeleteChunk
4243                  */
4244
4245                 chunkId = yaffs_FindAndDeleteChunkInFile(in, i, NULL);
4246                 if (chunkId > 0) {
4247                         if (chunkId <
4248                             (dev->internalStartBlock * dev->nChunksPerBlock)
4249                             || chunkId >=
4250                             ((dev->internalEndBlock +
4251                               1) * dev->nChunksPerBlock)) {
4252                                 T(YAFFS_TRACE_ALWAYS,
4253                                   (TSTR("Found daft chunkId %d for %d" TENDSTR),
4254                                    chunkId, i));
4255                         } else {
4256                                 in->nDataChunks--;
4257                                 yaffs_DeleteChunk(dev, chunkId, 1, __LINE__);
4258                         }
4259                 }
4260         }
4261
4262 }
4263
4264 int yaffs_ResizeFile(yaffs_Object * in, loff_t newSize)
4265 {
4266
4267         int oldFileSize = in->variant.fileVariant.fileSize;
4268         int newSizeOfPartialChunk;
4269         int newFullChunks;
4270
4271         yaffs_Device *dev = in->myDev;
4272
4273         yaffs_AddrToChunk(dev, newSize, &newFullChunks, &newSizeOfPartialChunk);
4274
4275         yaffs_FlushFilesChunkCache(in);
4276         yaffs_InvalidateWholeChunkCache(in);
4277
4278         yaffs_CheckGarbageCollection(dev);
4279
4280         if (in->variantType != YAFFS_OBJECT_TYPE_FILE) {
4281                 return yaffs_GetFileSize(in);
4282         }
4283
4284         if (newSize == oldFileSize) {
4285                 return oldFileSize;
4286         }
4287
4288         if (newSize < oldFileSize) {
4289
4290                 yaffs_PruneResizedChunks(in, newSize);
4291
4292                 if (newSizeOfPartialChunk != 0) {
4293                         int lastChunk = 1 + newFullChunks;
4294
4295                         __u8 *localBuffer = yaffs_GetTempBuffer(dev, __LINE__);
4296
4297                         /* Got to read and rewrite the last chunk with its new size and zero pad */
4298                         yaffs_ReadChunkDataFromObject(in, lastChunk,
4299                                                       localBuffer);
4300
4301                         memset(localBuffer + newSizeOfPartialChunk, 0,
4302                                dev->nDataBytesPerChunk - newSizeOfPartialChunk);
4303
4304                         yaffs_WriteChunkDataToObject(in, lastChunk, localBuffer,
4305                                                      newSizeOfPartialChunk, 1);
4306
4307                         yaffs_ReleaseTempBuffer(dev, localBuffer, __LINE__);
4308                 }
4309
4310                 in->variant.fileVariant.fileSize = newSize;
4311
4312                 yaffs_PruneFileStructure(dev, &in->variant.fileVariant);
4313         }
4314         /* Write a new object header.
4315          * show we've shrunk the file, if need be
4316          * Do this only if the file is not in the deleted directories.
4317          */
4318         if (in->parent->objectId != YAFFS_OBJECTID_UNLINKED &&
4319             in->parent->objectId != YAFFS_OBJECTID_DELETED) {
4320                 yaffs_UpdateObjectHeader(in, NULL, 0,
4321                                          (newSize < oldFileSize) ? 1 : 0, 0);
4322         }
4323
4324         return newSize;
4325 }
4326
4327 loff_t yaffs_GetFileSize(yaffs_Object * obj)
4328 {
4329         obj = yaffs_GetEquivalentObject(obj);
4330
4331         switch (obj->variantType) {
4332         case YAFFS_OBJECT_TYPE_FILE:
4333                 return obj->variant.fileVariant.fileSize;
4334         case YAFFS_OBJECT_TYPE_SYMLINK:
4335                 return yaffs_strlen(obj->variant.symLinkVariant.alias);
4336         default:
4337                 return 0;
4338         }
4339 }
4340
4341
4342
4343 int yaffs_FlushFile(yaffs_Object * in, int updateTime)
4344 {
4345         int retVal;
4346         if (in->dirty) {
4347                 yaffs_FlushFilesChunkCache(in);
4348                 if (updateTime) {
4349 #ifdef CONFIG_YAFFS_WINCE
4350                         yfsd_WinFileTimeNow(in->win_mtime);
4351 #else
4352
4353                         in->yst_mtime = Y_CURRENT_TIME;
4354
4355 #endif
4356                 }
4357
4358                 retVal =
4359                     (yaffs_UpdateObjectHeader(in, NULL, 0, 0, 0) >=
4360                      0) ? YAFFS_OK : YAFFS_FAIL;
4361         } else {
4362                 retVal = YAFFS_OK;
4363         }
4364
4365         return retVal;
4366
4367 }
4368
4369 static int yaffs_DoGenericObjectDeletion(yaffs_Object * in)
4370 {
4371
4372         /* First off, invalidate the file's data in the cache, without flushing. */
4373         yaffs_InvalidateWholeChunkCache(in);
4374
4375         if (in->myDev->isYaffs2 && (in->parent != in->myDev->deletedDir)) {
4376                 /* Move to the unlinked directory so we have a record that it was deleted. */
4377                 yaffs_ChangeObjectName(in, in->myDev->deletedDir, NULL, 0, 0);
4378
4379         }
4380
4381         yaffs_RemoveObjectFromDirectory(in);
4382         yaffs_DeleteChunk(in->myDev, in->chunkId, 1, __LINE__);
4383         in->chunkId = -1;
4384
4385         yaffs_FreeObject(in);
4386         return YAFFS_OK;
4387
4388 }
4389
4390 /* yaffs_DeleteFile deletes the whole file data
4391  * and the inode associated with the file.
4392  * It does not delete the links associated with the file.
4393  */
4394 static int yaffs_UnlinkFile(yaffs_Object * in)
4395 {
4396
4397         int retVal;
4398         int immediateDeletion = 0;
4399
4400         if (1) {
4401 #ifdef __KERNEL__
4402                 if (!in->myInode) {
4403                         immediateDeletion = 1;
4404
4405                 }
4406 #else
4407                 if (in->inUse <= 0) {
4408                         immediateDeletion = 1;
4409
4410                 }
4411 #endif
4412                 if (immediateDeletion) {
4413                         retVal =
4414                             yaffs_ChangeObjectName(in, in->myDev->deletedDir,
4415                                                    NULL, 0, 0);
4416                         T(YAFFS_TRACE_TRACING,
4417                           (TSTR("yaffs: immediate deletion of file %d" TENDSTR),
4418                            in->objectId));
4419                         in->deleted = 1;
4420                         in->myDev->nDeletedFiles++;
4421                         if (0 && in->myDev->isYaffs2) {
4422                                 yaffs_ResizeFile(in, 0);
4423                         }
4424                         yaffs_SoftDeleteFile(in);
4425                 } else {
4426                         retVal =
4427                             yaffs_ChangeObjectName(in, in->myDev->unlinkedDir,
4428                                                    NULL, 0, 0);
4429                 }
4430
4431         }
4432         return retVal;
4433 }
4434
4435 int yaffs_DeleteFile(yaffs_Object * in)
4436 {
4437         int retVal = YAFFS_OK;
4438
4439         if (in->nDataChunks > 0) {
4440                 /* Use soft deletion if there is data in the file */
4441                 if (!in->unlinked) {
4442                         retVal = yaffs_UnlinkFile(in);
4443                 }
4444                 if (retVal == YAFFS_OK && in->unlinked && !in->deleted) {
4445                         in->deleted = 1;
4446                         in->myDev->nDeletedFiles++;
4447                         yaffs_SoftDeleteFile(in);
4448                 }
4449                 return in->deleted ? YAFFS_OK : YAFFS_FAIL;
4450         } else {
4451                 /* The file has no data chunks so we toss it immediately */
4452                 yaffs_FreeTnode(in->myDev, in->variant.fileVariant.top);
4453                 in->variant.fileVariant.top = NULL;
4454                 yaffs_DoGenericObjectDeletion(in);
4455
4456                 return YAFFS_OK;
4457         }
4458 }
4459
4460 static int yaffs_DeleteDirectory(yaffs_Object * in)
4461 {
4462         /* First check that the directory is empty. */
4463         if (list_empty(&in->variant.directoryVariant.children)) {
4464                 return yaffs_DoGenericObjectDeletion(in);
4465         }
4466
4467         return YAFFS_FAIL;
4468
4469 }
4470
4471 static int yaffs_DeleteSymLink(yaffs_Object * in)
4472 {
4473         YFREE(in->variant.symLinkVariant.alias);
4474
4475         return yaffs_DoGenericObjectDeletion(in);
4476 }
4477
4478 static int yaffs_DeleteHardLink(yaffs_Object * in)
4479 {
4480         /* remove this hardlink from the list assocaited with the equivalent
4481          * object
4482          */
4483         list_del(&in->hardLinks);
4484         return yaffs_DoGenericObjectDeletion(in);
4485 }
4486
4487 static void yaffs_DestroyObject(yaffs_Object * obj)
4488 {
4489         switch (obj->variantType) {
4490         case YAFFS_OBJECT_TYPE_FILE:
4491                 yaffs_DeleteFile(obj);
4492                 break;
4493         case YAFFS_OBJECT_TYPE_DIRECTORY:
4494                 yaffs_DeleteDirectory(obj);
4495                 break;
4496         case YAFFS_OBJECT_TYPE_SYMLINK:
4497                 yaffs_DeleteSymLink(obj);
4498                 break;
4499         case YAFFS_OBJECT_TYPE_HARDLINK:
4500                 yaffs_DeleteHardLink(obj);
4501                 break;
4502         case YAFFS_OBJECT_TYPE_SPECIAL:
4503                 yaffs_DoGenericObjectDeletion(obj);
4504                 break;
4505         case YAFFS_OBJECT_TYPE_UNKNOWN:
4506                 break;          /* should not happen. */
4507         }
4508 }
4509
4510 static int yaffs_UnlinkWorker(yaffs_Object * obj)
4511 {
4512
4513         if (obj->variantType == YAFFS_OBJECT_TYPE_HARDLINK) {
4514                 return yaffs_DeleteHardLink(obj);
4515         } else if (!list_empty(&obj->hardLinks)) {
4516                 /* Curve ball: We're unlinking an object that has a hardlink.
4517                  *
4518                  * This problem arises because we are not strictly following
4519                  * The Linux link/inode model.
4520                  *
4521                  * We can't really delete the object.
4522                  * Instead, we do the following:
4523                  * - Select a hardlink.
4524                  * - Unhook it from the hard links
4525                  * - Unhook it from its parent directory (so that the rename can work)
4526                  * - Rename the object to the hardlink's name.
4527                  * - Delete the hardlink
4528                  */
4529
4530                 yaffs_Object *hl;
4531                 int retVal;
4532                 YCHAR name[YAFFS_MAX_NAME_LENGTH + 1];
4533
4534                 hl = list_entry(obj->hardLinks.next, yaffs_Object, hardLinks);
4535
4536                 list_del_init(&hl->hardLinks);
4537                 list_del_init(&hl->siblings);
4538
4539                 yaffs_GetObjectName(hl, name, YAFFS_MAX_NAME_LENGTH + 1);
4540
4541                 retVal = yaffs_ChangeObjectName(obj, hl->parent, name, 0, 0);
4542
4543                 if (retVal == YAFFS_OK) {
4544                         retVal = yaffs_DoGenericObjectDeletion(hl);
4545                 }
4546                 return retVal;
4547
4548         } else {
4549                 switch (obj->variantType) {
4550                 case YAFFS_OBJECT_TYPE_FILE:
4551                         return yaffs_UnlinkFile(obj);
4552                         break;
4553                 case YAFFS_OBJECT_TYPE_DIRECTORY:
4554                         return yaffs_DeleteDirectory(obj);
4555                         break;
4556                 case YAFFS_OBJECT_TYPE_SYMLINK:
4557                         return yaffs_DeleteSymLink(obj);
4558                         break;
4559                 case YAFFS_OBJECT_TYPE_SPECIAL:
4560                         return yaffs_DoGenericObjectDeletion(obj);
4561                         break;
4562                 case YAFFS_OBJECT_TYPE_HARDLINK:
4563                 case YAFFS_OBJECT_TYPE_UNKNOWN:
4564                 default:
4565                         return YAFFS_FAIL;
4566                 }
4567         }
4568 }
4569
4570
4571 static int yaffs_UnlinkObject( yaffs_Object *obj)
4572 {
4573
4574         if (obj && obj->unlinkAllowed) {
4575                 return yaffs_UnlinkWorker(obj);
4576         }
4577
4578         return YAFFS_FAIL;
4579
4580 }
4581 int yaffs_Unlink(yaffs_Object * dir, const YCHAR * name)
4582 {
4583         yaffs_Object *obj;
4584
4585         obj = yaffs_FindObjectByName(dir, name);
4586         return yaffs_UnlinkObject(obj);
4587 }
4588
4589 /*----------------------- Initialisation Scanning ---------------------- */
4590
4591 static void yaffs_HandleShadowedObject(yaffs_Device * dev, int objId,
4592                                        int backwardScanning)
4593 {
4594         yaffs_Object *obj;
4595
4596         if (!backwardScanning) {
4597                 /* Handle YAFFS1 forward scanning case
4598                  * For YAFFS1 we always do the deletion
4599                  */
4600
4601         } else {
4602                 /* Handle YAFFS2 case (backward scanning)
4603                  * If the shadowed object exists then ignore.
4604                  */
4605                 if (yaffs_FindObjectByNumber(dev, objId)) {
4606                         return;
4607                 }
4608         }
4609
4610         /* Let's create it (if it does not exist) assuming it is a file so that it can do shrinking etc.
4611          * We put it in unlinked dir to be cleaned up after the scanning
4612          */
4613         obj =
4614             yaffs_FindOrCreateObjectByNumber(dev, objId,
4615                                              YAFFS_OBJECT_TYPE_FILE);
4616         yaffs_AddObjectToDirectory(dev->unlinkedDir, obj);
4617         obj->variant.fileVariant.shrinkSize = 0;
4618         obj->valid = 1;         /* So that we don't read any other info for this file */
4619
4620 }
4621
4622 typedef struct {
4623         int seq;
4624         int block;
4625 } yaffs_BlockIndex;
4626
4627
4628 static void yaffs_HardlinkFixup(yaffs_Device *dev, yaffs_Object *hardList)
4629 {
4630         yaffs_Object *hl;
4631         yaffs_Object *in;
4632
4633         while (hardList) {
4634                 hl = hardList;
4635                 hardList = (yaffs_Object *) (hardList->hardLinks.next);
4636
4637                 in = yaffs_FindObjectByNumber(dev,
4638                                               hl->variant.hardLinkVariant.
4639                                               equivalentObjectId);
4640
4641                 if (in) {
4642                         /* Add the hardlink pointers */
4643                         hl->variant.hardLinkVariant.equivalentObject = in;
4644                         list_add(&hl->hardLinks, &in->hardLinks);
4645                 } else {
4646                         /* Todo Need to report/handle this better.
4647                          * Got a problem... hardlink to a non-existant object
4648                          */
4649                         hl->variant.hardLinkVariant.equivalentObject = NULL;
4650                         INIT_LIST_HEAD(&hl->hardLinks);
4651
4652                 }
4653
4654         }
4655
4656 }
4657
4658
4659
4660
4661
4662 static int ybicmp(const void *a, const void *b){
4663     register int aseq = ((yaffs_BlockIndex *)a)->seq;
4664     register int bseq = ((yaffs_BlockIndex *)b)->seq;
4665     register int ablock = ((yaffs_BlockIndex *)a)->block;
4666     register int bblock = ((yaffs_BlockIndex *)b)->block;
4667     if( aseq == bseq )
4668         return ablock - bblock;
4669     else
4670         return aseq - bseq;
4671
4672 }
4673
4674 static int yaffs_Scan(yaffs_Device * dev)
4675 {
4676         yaffs_ExtendedTags tags;
4677         int blk;
4678         int blockIterator;
4679         int startIterator;
4680         int endIterator;
4681         int nBlocksToScan = 0;
4682         int result;
4683
4684         int chunk;
4685         int c;
4686         int deleted;
4687         yaffs_BlockState state;
4688         yaffs_Object *hardList = NULL;
4689         yaffs_Object *hl;
4690         yaffs_BlockInfo *bi;
4691         int sequenceNumber;
4692         yaffs_ObjectHeader *oh;
4693         yaffs_Object *in;
4694         yaffs_Object *parent;
4695         int nBlocks = dev->internalEndBlock - dev->internalStartBlock + 1;
4696
4697         __u8 *chunkData;
4698
4699         yaffs_BlockIndex *blockIndex = NULL;
4700
4701         if (dev->isYaffs2) {
4702                 T(YAFFS_TRACE_SCAN,
4703                   (TSTR("yaffs_Scan is not for YAFFS2!" TENDSTR)));
4704                 return YAFFS_FAIL;
4705         }
4706
4707         //TODO  Throw all the yaffs2 stuuf out of yaffs_Scan since it is only for yaffs1 format.
4708
4709         T(YAFFS_TRACE_SCAN,
4710           (TSTR("yaffs_Scan starts  intstartblk %d intendblk %d..." TENDSTR),
4711            dev->internalStartBlock, dev->internalEndBlock));
4712
4713         chunkData = yaffs_GetTempBuffer(dev, __LINE__);
4714
4715         dev->sequenceNumber = YAFFS_LOWEST_SEQUENCE_NUMBER;
4716
4717         if (dev->isYaffs2) {
4718                 blockIndex = YMALLOC(nBlocks * sizeof(yaffs_BlockIndex));
4719         }
4720
4721         /* Scan all the blocks to determine their state */
4722         for (blk = dev->internalStartBlock; blk <= dev->internalEndBlock; blk++) {
4723                 bi = yaffs_GetBlockInfo(dev, blk);
4724                 yaffs_ClearChunkBits(dev, blk);
4725                 bi->pagesInUse = 0;
4726                 bi->softDeletions = 0;
4727
4728                 yaffs_QueryInitialBlockState(dev, blk, &state, &sequenceNumber);
4729
4730                 bi->blockState = state;
4731                 bi->sequenceNumber = sequenceNumber;
4732
4733                 T(YAFFS_TRACE_SCAN_DEBUG,
4734                   (TSTR("Block scanning block %d state %d seq %d" TENDSTR), blk,
4735                    state, sequenceNumber));
4736
4737                 if (state == YAFFS_BLOCK_STATE_DEAD) {
4738                         T(YAFFS_TRACE_BAD_BLOCKS,
4739                           (TSTR("block %d is bad" TENDSTR), blk));
4740                 } else if (state == YAFFS_BLOCK_STATE_EMPTY) {
4741                         T(YAFFS_TRACE_SCAN_DEBUG,
4742                           (TSTR("Block empty " TENDSTR)));
4743                         dev->nErasedBlocks++;
4744                         dev->nFreeChunks += dev->nChunksPerBlock;
4745                 } else if (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING) {
4746
4747                         /* Determine the highest sequence number */
4748                         if (dev->isYaffs2 &&
4749                             sequenceNumber >= YAFFS_LOWEST_SEQUENCE_NUMBER &&
4750                             sequenceNumber < YAFFS_HIGHEST_SEQUENCE_NUMBER) {
4751
4752                                 blockIndex[nBlocksToScan].seq = sequenceNumber;
4753                                 blockIndex[nBlocksToScan].block = blk;
4754
4755                                 nBlocksToScan++;
4756
4757                                 if (sequenceNumber >= dev->sequenceNumber) {
4758                                         dev->sequenceNumber = sequenceNumber;
4759                                 }
4760                         } else if (dev->isYaffs2) {
4761                                 /* TODO: Nasty sequence number! */
4762                                 T(YAFFS_TRACE_SCAN,
4763                                   (TSTR
4764                                    ("Block scanning block %d has bad sequence number %d"
4765                                     TENDSTR), blk, sequenceNumber));
4766
4767                         }
4768                 }
4769         }
4770
4771         /* Sort the blocks
4772          * Dungy old bubble sort for now...
4773          */
4774         if (dev->isYaffs2) {
4775                 yaffs_BlockIndex temp;
4776                 int i;
4777                 int j;
4778
4779                 for (i = 0; i < nBlocksToScan; i++)
4780                         for (j = i + 1; j < nBlocksToScan; j++)
4781                                 if (blockIndex[i].seq > blockIndex[j].seq) {
4782                                         temp = blockIndex[j];
4783                                         blockIndex[j] = blockIndex[i];
4784                                         blockIndex[i] = temp;
4785                                 }
4786         }
4787
4788         /* Now scan the blocks looking at the data. */
4789         if (dev->isYaffs2) {
4790                 startIterator = 0;
4791                 endIterator = nBlocksToScan - 1;
4792                 T(YAFFS_TRACE_SCAN_DEBUG,
4793                   (TSTR("%d blocks to be scanned" TENDSTR), nBlocksToScan));
4794         } else {
4795                 startIterator = dev->internalStartBlock;
4796                 endIterator = dev->internalEndBlock;
4797         }
4798
4799         /* For each block.... */
4800         for (blockIterator = startIterator; blockIterator <= endIterator;
4801              blockIterator++) {
4802
4803                 if (dev->isYaffs2) {
4804                         /* get the block to scan in the correct order */
4805                         blk = blockIndex[blockIterator].block;
4806                 } else {
4807                         blk = blockIterator;
4808                 }
4809
4810                 bi = yaffs_GetBlockInfo(dev, blk);
4811                 state = bi->blockState;
4812
4813                 deleted = 0;
4814
4815                 /* For each chunk in each block that needs scanning....*/
4816                 for (c = 0; c < dev->nChunksPerBlock &&
4817                      state == YAFFS_BLOCK_STATE_NEEDS_SCANNING; c++) {
4818                         /* Read the tags and decide what to do */
4819                         chunk = blk * dev->nChunksPerBlock + c;
4820
4821                         result = yaffs_ReadChunkWithTagsFromNAND(dev, chunk, NULL,
4822                                                         &tags);
4823
4824                         /* Let's have a good look at this chunk... */
4825
4826                         if (!dev->isYaffs2 && tags.chunkDeleted) {
4827                                 /* YAFFS1 only...
4828                                  * A deleted chunk
4829                                  */
4830                                 deleted++;
4831                                 dev->nFreeChunks++;
4832                                 /*T((" %d %d deleted\n",blk,c)); */
4833                         } else if (!tags.chunkUsed) {
4834                                 /* An unassigned chunk in the block
4835                                  * This means that either the block is empty or
4836                                  * this is the one being allocated from
4837                                  */
4838
4839                                 if (c == 0) {
4840                                         /* We're looking at the first chunk in the block so the block is unused */
4841                                         state = YAFFS_BLOCK_STATE_EMPTY;
4842                                         dev->nErasedBlocks++;
4843                                 } else {
4844                                         /* this is the block being allocated from */
4845                                         T(YAFFS_TRACE_SCAN,
4846                                           (TSTR
4847                                            (" Allocating from %d %d" TENDSTR),
4848                                            blk, c));
4849                                         state = YAFFS_BLOCK_STATE_ALLOCATING;
4850                                         dev->allocationBlock = blk;
4851                                         dev->allocationPage = c;
4852                                         dev->allocationBlockFinder = blk;
4853                                         /* Set it to here to encourage the allocator to go forth from here. */
4854
4855                                         /* Yaffs2 sanity check:
4856                                          * This should be the one with the highest sequence number
4857                                          */
4858                                         if (dev->isYaffs2
4859                                             && (dev->sequenceNumber !=
4860                                                 bi->sequenceNumber)) {
4861                                                 T(YAFFS_TRACE_ALWAYS,
4862                                                   (TSTR
4863                                                    ("yaffs: Allocation block %d was not highest sequence id:"
4864                                                     " block seq = %d, dev seq = %d"
4865                                                     TENDSTR), blk,bi->sequenceNumber,dev->sequenceNumber));
4866                                         }
4867                                 }
4868
4869                                 dev->nFreeChunks += (dev->nChunksPerBlock - c);
4870                         } else if (tags.chunkId > 0) {
4871                                 /* chunkId > 0 so it is a data chunk... */
4872                                 unsigned int endpos;
4873
4874                                 yaffs_SetChunkBit(dev, blk, c);
4875                                 bi->pagesInUse++;
4876
4877                                 in = yaffs_FindOrCreateObjectByNumber(dev,
4878                                                                       tags.
4879                                                                       objectId,
4880                                                                       YAFFS_OBJECT_TYPE_FILE);
4881                                 /* PutChunkIntoFile checks for a clash (two data chunks with
4882                                  * the same chunkId).
4883                                  */
4884                                 yaffs_PutChunkIntoFile(in, tags.chunkId, chunk,
4885                                                        1);
4886                                 endpos =
4887                                     (tags.chunkId - 1) * dev->nDataBytesPerChunk +
4888                                     tags.byteCount;
4889                                 if (in->variantType == YAFFS_OBJECT_TYPE_FILE
4890                                     && in->variant.fileVariant.scannedFileSize <
4891                                     endpos) {
4892                                         in->variant.fileVariant.
4893                                             scannedFileSize = endpos;
4894                                         if (!dev->useHeaderFileSize) {
4895                                                 in->variant.fileVariant.
4896                                                     fileSize =
4897                                                     in->variant.fileVariant.
4898                                                     scannedFileSize;
4899                                         }
4900
4901                                 }
4902                                 /* T((" %d %d data %d %d\n",blk,c,tags.objectId,tags.chunkId));   */
4903                         } else {
4904                                 /* chunkId == 0, so it is an ObjectHeader.
4905                                  * Thus, we read in the object header and make the object
4906                                  */
4907                                 yaffs_SetChunkBit(dev, blk, c);
4908                                 bi->pagesInUse++;
4909
4910                                 result = yaffs_ReadChunkWithTagsFromNAND(dev, chunk,
4911                                                                 chunkData,
4912                                                                 NULL);
4913
4914                                 oh = (yaffs_ObjectHeader *) chunkData;
4915
4916                                 in = yaffs_FindObjectByNumber(dev,
4917                                                               tags.objectId);
4918                                 if (in && in->variantType != oh->type) {
4919                                         /* This should not happen, but somehow
4920                                          * Wev'e ended up with an objectId that has been reused but not yet
4921                                          * deleted, and worse still it has changed type. Delete the old object.
4922                                          */
4923
4924                                         yaffs_DestroyObject(in);
4925
4926                                         in = 0;
4927                                 }
4928
4929                                 in = yaffs_FindOrCreateObjectByNumber(dev,
4930                                                                       tags.
4931                                                                       objectId,
4932                                                                       oh->type);
4933
4934                                 if (oh->shadowsObject > 0) {
4935                                         yaffs_HandleShadowedObject(dev,
4936                                                                    oh->
4937                                                                    shadowsObject,
4938                                                                    0);
4939                                 }
4940
4941                                 if (in->valid) {
4942                                         /* We have already filled this one. We have a duplicate and need to resolve it. */
4943
4944                                         unsigned existingSerial = in->serial;
4945                                         unsigned newSerial = tags.serialNumber;
4946
4947                                         if (dev->isYaffs2 ||
4948                                             ((existingSerial + 1) & 3) ==
4949                                             newSerial) {
4950                                                 /* Use new one - destroy the exisiting one */
4951                                                 yaffs_DeleteChunk(dev,
4952                                                                   in->chunkId,
4953                                                                   1, __LINE__);
4954                                                 in->valid = 0;
4955                                         } else {
4956                                                 /* Use existing - destroy this one. */
4957                                                 yaffs_DeleteChunk(dev, chunk, 1,
4958                                                                   __LINE__);
4959                                         }
4960                                 }
4961
4962                                 if (!in->valid &&
4963                                     (tags.objectId == YAFFS_OBJECTID_ROOT ||
4964                                      tags.objectId == YAFFS_OBJECTID_LOSTNFOUND)) {
4965                                         /* We only load some info, don't fiddle with directory structure */
4966                                         in->valid = 1;
4967                                         in->variantType = oh->type;
4968
4969                                         in->yst_mode = oh->yst_mode;
4970 #ifdef CONFIG_YAFFS_WINCE
4971                                         in->win_atime[0] = oh->win_atime[0];
4972                                         in->win_ctime[0] = oh->win_ctime[0];
4973                                         in->win_mtime[0] = oh->win_mtime[0];
4974                                         in->win_atime[1] = oh->win_atime[1];
4975                                         in->win_ctime[1] = oh->win_ctime[1];
4976                                         in->win_mtime[1] = oh->win_mtime[1];
4977 #else
4978                                         in->yst_uid = oh->yst_uid;
4979                                         in->yst_gid = oh->yst_gid;
4980                                         in->yst_atime = oh->yst_atime;
4981                                         in->yst_mtime = oh->yst_mtime;
4982                                         in->yst_ctime = oh->yst_ctime;
4983                                         in->yst_rdev = oh->yst_rdev;
4984 #endif
4985                                         in->chunkId = chunk;
4986
4987                                 } else if (!in->valid) {
4988                                         /* we need to load this info */
4989
4990                                         in->valid = 1;
4991                                         in->variantType = oh->type;
4992
4993                                         in->yst_mode = oh->yst_mode;
4994 #ifdef CONFIG_YAFFS_WINCE
4995                                         in->win_atime[0] = oh->win_atime[0];
4996                                         in->win_ctime[0] = oh->win_ctime[0];
4997                                         in->win_mtime[0] = oh->win_mtime[0];
4998                                         in->win_atime[1] = oh->win_atime[1];
4999                                         in->win_ctime[1] = oh->win_ctime[1];
5000                                         in->win_mtime[1] = oh->win_mtime[1];
5001 #else
5002                                         in->yst_uid = oh->yst_uid;
5003                                         in->yst_gid = oh->yst_gid;
5004                                         in->yst_atime = oh->yst_atime;
5005                                         in->yst_mtime = oh->yst_mtime;
5006                                         in->yst_ctime = oh->yst_ctime;
5007                                         in->yst_rdev = oh->yst_rdev;
5008 #endif
5009                                         in->chunkId = chunk;
5010
5011                                         yaffs_SetObjectName(in, oh->name);
5012                                         in->dirty = 0;
5013
5014                                         /* directory stuff...
5015                                          * hook up to parent
5016                                          */
5017
5018                                         parent =
5019                                             yaffs_FindOrCreateObjectByNumber
5020                                             (dev, oh->parentObjectId,
5021                                              YAFFS_OBJECT_TYPE_DIRECTORY);
5022                                         if (parent->variantType ==
5023                                             YAFFS_OBJECT_TYPE_UNKNOWN) {
5024                                                 /* Set up as a directory */
5025                                                 parent->variantType =
5026                                                     YAFFS_OBJECT_TYPE_DIRECTORY;
5027                                                 INIT_LIST_HEAD(&parent->variant.
5028                                                                directoryVariant.
5029                                                                children);
5030                                         } else if (parent->variantType !=
5031                                                    YAFFS_OBJECT_TYPE_DIRECTORY)
5032                                         {
5033                                                 /* Hoosterman, another problem....
5034                                                  * We're trying to use a non-directory as a directory
5035                                                  */
5036
5037                                                 T(YAFFS_TRACE_ERROR,
5038                                                   (TSTR
5039                                                    ("yaffs tragedy: attempting to use non-directory as"
5040                                                     " a directory in scan. Put in lost+found."
5041                                                     TENDSTR)));
5042                                                 parent = dev->lostNFoundDir;
5043                                         }
5044
5045                                         yaffs_AddObjectToDirectory(parent, in);
5046
5047                                         if (0 && (parent == dev->deletedDir ||
5048                                                   parent == dev->unlinkedDir)) {
5049                                                 in->deleted = 1;        /* If it is unlinked at start up then it wants deleting */
5050                                                 dev->nDeletedFiles++;
5051                                         }
5052                                         /* Note re hardlinks.
5053                                          * Since we might scan a hardlink before its equivalent object is scanned
5054                                          * we put them all in a list.
5055                                          * After scanning is complete, we should have all the objects, so we run through this
5056                                          * list and fix up all the chains.
5057                                          */
5058
5059                                         switch (in->variantType) {
5060                                         case YAFFS_OBJECT_TYPE_UNKNOWN:
5061                                                 /* Todo got a problem */
5062                                                 break;
5063                                         case YAFFS_OBJECT_TYPE_FILE:
5064                                                 if (dev->isYaffs2
5065                                                     && oh->isShrink) {
5066                                                         /* Prune back the shrunken chunks */
5067                                                         yaffs_PruneResizedChunks
5068                                                             (in, oh->fileSize);
5069                                                         /* Mark the block as having a shrinkHeader */
5070                                                         bi->hasShrinkHeader = 1;
5071                                                 }
5072
5073                                                 if (dev->useHeaderFileSize)
5074
5075                                                         in->variant.fileVariant.
5076                                                             fileSize =
5077                                                             oh->fileSize;
5078
5079                                                 break;
5080                                         case YAFFS_OBJECT_TYPE_HARDLINK:
5081                                                 in->variant.hardLinkVariant.
5082                                                     equivalentObjectId =
5083                                                     oh->equivalentObjectId;
5084                                                 in->hardLinks.next =
5085                                                     (struct list_head *)
5086                                                     hardList;
5087                                                 hardList = in;
5088                                                 break;
5089                                         case YAFFS_OBJECT_TYPE_DIRECTORY:
5090                                                 /* Do nothing */
5091                                                 break;
5092                                         case YAFFS_OBJECT_TYPE_SPECIAL:
5093                                                 /* Do nothing */
5094                                                 break;
5095                                         case YAFFS_OBJECT_TYPE_SYMLINK:
5096                                                 in->variant.symLinkVariant.
5097                                                     alias =
5098                                                     yaffs_CloneString(oh->alias);
5099                                                 break;
5100                                         }
5101
5102                                         if (parent == dev->deletedDir) {
5103                                                 yaffs_DestroyObject(in);
5104                                                 bi->hasShrinkHeader = 1;
5105                                         }
5106                                 }
5107                         }
5108                 }
5109
5110                 if (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING) {
5111                         /* If we got this far while scanning, then the block is fully allocated.*/
5112                         state = YAFFS_BLOCK_STATE_FULL;
5113                 }
5114
5115                 bi->blockState = state;
5116
5117                 /* Now let's see if it was dirty */
5118                 if (bi->pagesInUse == 0 &&
5119                     !bi->hasShrinkHeader &&
5120                     bi->blockState == YAFFS_BLOCK_STATE_FULL) {
5121                         yaffs_BlockBecameDirty(dev, blk);
5122                 }
5123
5124         }
5125
5126         if (blockIndex) {
5127                 YFREE(blockIndex);
5128         }
5129
5130
5131         /* Ok, we've done all the scanning.
5132          * Fix up the hard link chains.
5133          * We should now have scanned all the objects, now it's time to add these
5134          * hardlinks.
5135          */
5136
5137         yaffs_HardlinkFixup(dev,hardList);
5138
5139         /* Handle the unlinked files. Since they were left in an unlinked state we should
5140          * just delete them.
5141          */
5142         {
5143                 struct list_head *i;
5144                 struct list_head *n;
5145
5146                 yaffs_Object *l;
5147                 /* Soft delete all the unlinked files */
5148                 list_for_each_safe(i, n,
5149                                    &dev->unlinkedDir->variant.directoryVariant.
5150                                    children) {
5151                         if (i) {
5152                                 l = list_entry(i, yaffs_Object, siblings);
5153                                 yaffs_DestroyObject(l);
5154                         }
5155                 }
5156         }
5157
5158         yaffs_ReleaseTempBuffer(dev, chunkData, __LINE__);
5159
5160         T(YAFFS_TRACE_SCAN, (TSTR("yaffs_Scan ends" TENDSTR)));
5161
5162         return YAFFS_OK;
5163 }
5164
5165 static void yaffs_CheckObjectDetailsLoaded(yaffs_Object *in)
5166 {
5167         __u8 *chunkData;
5168         yaffs_ObjectHeader *oh;
5169         yaffs_Device *dev = in->myDev;
5170         yaffs_ExtendedTags tags;
5171         int result;
5172
5173 #if 0
5174         T(YAFFS_TRACE_SCAN,(TSTR("details for object %d %s loaded" TENDSTR),
5175                 in->objectId,
5176                 in->lazyLoaded ? "not yet" : "already"));
5177 #endif
5178
5179         if(in->lazyLoaded){
5180                 in->lazyLoaded = 0;
5181                 chunkData = yaffs_GetTempBuffer(dev, __LINE__);
5182
5183                 result = yaffs_ReadChunkWithTagsFromNAND(dev,in->chunkId,chunkData,&tags);
5184                 oh = (yaffs_ObjectHeader *) chunkData;
5185
5186                 in->yst_mode = oh->yst_mode;
5187 #ifdef CONFIG_YAFFS_WINCE
5188                 in->win_atime[0] = oh->win_atime[0];
5189                 in->win_ctime[0] = oh->win_ctime[0];
5190                 in->win_mtime[0] = oh->win_mtime[0];
5191                 in->win_atime[1] = oh->win_atime[1];
5192                 in->win_ctime[1] = oh->win_ctime[1];
5193                 in->win_mtime[1] = oh->win_mtime[1];
5194 #else
5195                 in->yst_uid = oh->yst_uid;
5196                 in->yst_gid = oh->yst_gid;
5197                 in->yst_atime = oh->yst_atime;
5198                 in->yst_mtime = oh->yst_mtime;
5199                 in->yst_ctime = oh->yst_ctime;
5200                 in->yst_rdev = oh->yst_rdev;
5201
5202 #endif
5203                 yaffs_SetObjectName(in, oh->name);
5204
5205                 if(in->variantType == YAFFS_OBJECT_TYPE_SYMLINK)
5206                          in->variant.symLinkVariant.alias =
5207                                                     yaffs_CloneString(oh->alias);
5208
5209                 yaffs_ReleaseTempBuffer(dev,chunkData, __LINE__);
5210         }
5211 }
5212
5213 static int yaffs_ScanBackwards(yaffs_Device * dev)
5214 {
5215         yaffs_ExtendedTags tags;
5216         int blk;
5217         int blockIterator;
5218         int startIterator;
5219         int endIterator;
5220         int nBlocksToScan = 0;
5221
5222         int chunk;
5223         int result;
5224         int c;
5225         int deleted;
5226         yaffs_BlockState state;
5227         yaffs_Object *hardList = NULL;
5228         yaffs_BlockInfo *bi;
5229         int sequenceNumber;
5230         yaffs_ObjectHeader *oh;
5231         yaffs_Object *in;
5232         yaffs_Object *parent;
5233         int nBlocks = dev->internalEndBlock - dev->internalStartBlock + 1;
5234         int itsUnlinked;
5235         __u8 *chunkData;
5236
5237         int fileSize;
5238         int isShrink;
5239         int foundChunksInBlock;
5240         int equivalentObjectId;
5241
5242
5243         yaffs_BlockIndex *blockIndex = NULL;
5244         int altBlockIndex = 0;
5245
5246         if (!dev->isYaffs2) {
5247                 T(YAFFS_TRACE_SCAN,
5248                   (TSTR("yaffs_ScanBackwards is only for YAFFS2!" TENDSTR)));
5249                 return YAFFS_FAIL;
5250         }
5251
5252         T(YAFFS_TRACE_SCAN,
5253           (TSTR
5254            ("yaffs_ScanBackwards starts  intstartblk %d intendblk %d..."
5255             TENDSTR), dev->internalStartBlock, dev->internalEndBlock));
5256
5257
5258         dev->sequenceNumber = YAFFS_LOWEST_SEQUENCE_NUMBER;
5259
5260         blockIndex = YMALLOC(nBlocks * sizeof(yaffs_BlockIndex));
5261
5262         if(!blockIndex) {
5263                 blockIndex = YMALLOC_ALT(nBlocks * sizeof(yaffs_BlockIndex));
5264                 altBlockIndex = 1;
5265         }
5266
5267         if(!blockIndex) {
5268                 T(YAFFS_TRACE_SCAN,
5269                   (TSTR("yaffs_Scan() could not allocate block index!" TENDSTR)));
5270                 return YAFFS_FAIL;
5271         }
5272
5273         chunkData = yaffs_GetTempBuffer(dev, __LINE__);
5274
5275         /* Scan all the blocks to determine their state */
5276         for (blk = dev->internalStartBlock; blk <= dev->internalEndBlock; blk++) {
5277                 bi = yaffs_GetBlockInfo(dev, blk);
5278                 yaffs_ClearChunkBits(dev, blk);
5279                 bi->pagesInUse = 0;
5280                 bi->softDeletions = 0;
5281
5282                 yaffs_QueryInitialBlockState(dev, blk, &state, &sequenceNumber);
5283
5284                 bi->blockState = state;
5285                 bi->sequenceNumber = sequenceNumber;
5286
5287                 if(bi->sequenceNumber == YAFFS_SEQUENCE_CHECKPOINT_DATA)
5288                         bi->blockState = state = YAFFS_BLOCK_STATE_CHECKPOINT;
5289
5290                 T(YAFFS_TRACE_SCAN_DEBUG,
5291                   (TSTR("Block scanning block %d state %d seq %d" TENDSTR), blk,
5292                    state, sequenceNumber));
5293
5294
5295                 if(state == YAFFS_BLOCK_STATE_CHECKPOINT){
5296                         /* todo .. fix free space ? */
5297
5298                 } else if (state == YAFFS_BLOCK_STATE_DEAD) {
5299                         T(YAFFS_TRACE_BAD_BLOCKS,
5300                           (TSTR("block %d is bad" TENDSTR), blk));
5301                 } else if (state == YAFFS_BLOCK_STATE_EMPTY) {
5302                         T(YAFFS_TRACE_SCAN_DEBUG,
5303                           (TSTR("Block empty " TENDSTR)));
5304                         dev->nErasedBlocks++;
5305                         dev->nFreeChunks += dev->nChunksPerBlock;
5306                 } else if (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING) {
5307
5308                         /* Determine the highest sequence number */
5309                         if (dev->isYaffs2 &&
5310                             sequenceNumber >= YAFFS_LOWEST_SEQUENCE_NUMBER &&
5311                             sequenceNumber < YAFFS_HIGHEST_SEQUENCE_NUMBER) {
5312
5313                                 blockIndex[nBlocksToScan].seq = sequenceNumber;
5314                                 blockIndex[nBlocksToScan].block = blk;
5315
5316                                 nBlocksToScan++;
5317
5318                                 if (sequenceNumber >= dev->sequenceNumber) {
5319                                         dev->sequenceNumber = sequenceNumber;
5320                                 }
5321                         } else if (dev->isYaffs2) {
5322                                 /* TODO: Nasty sequence number! */
5323                                 T(YAFFS_TRACE_SCAN,
5324                                   (TSTR
5325                                    ("Block scanning block %d has bad sequence number %d"
5326                                     TENDSTR), blk, sequenceNumber));
5327
5328                         }
5329                 }
5330         }
5331
5332         T(YAFFS_TRACE_SCAN,
5333         (TSTR("%d blocks to be sorted..." TENDSTR), nBlocksToScan));
5334
5335
5336
5337         YYIELD();
5338
5339         /* Sort the blocks */
5340 #ifndef CONFIG_YAFFS_USE_OWN_SORT
5341         {
5342                 /* Use qsort now. */
5343                 qsort(blockIndex, nBlocksToScan, sizeof(yaffs_BlockIndex), ybicmp);
5344         }
5345 #else
5346         {
5347                 /* Dungy old bubble sort... */
5348
5349                 yaffs_BlockIndex temp;
5350                 int i;
5351                 int j;
5352
5353                 for (i = 0; i < nBlocksToScan; i++)
5354                         for (j = i + 1; j < nBlocksToScan; j++)
5355                                 if (blockIndex[i].seq > blockIndex[j].seq) {
5356                                         temp = blockIndex[j];
5357                                         blockIndex[j] = blockIndex[i];
5358                                         blockIndex[i] = temp;
5359                                 }
5360         }
5361 #endif
5362
5363         YYIELD();
5364
5365         T(YAFFS_TRACE_SCAN, (TSTR("...done" TENDSTR)));
5366
5367         /* Now scan the blocks looking at the data. */
5368         startIterator = 0;
5369         endIterator = nBlocksToScan - 1;
5370         T(YAFFS_TRACE_SCAN_DEBUG,
5371           (TSTR("%d blocks to be scanned" TENDSTR), nBlocksToScan));
5372
5373         /* For each block.... backwards */
5374         for (blockIterator = endIterator; blockIterator >= startIterator;
5375              blockIterator--) {
5376                 /* Cooperative multitasking! This loop can run for so
5377                    long that watchdog timers expire. */
5378                 YYIELD();
5379
5380                 /* get the block to scan in the correct order */
5381                 blk = blockIndex[blockIterator].block;
5382
5383                 bi = yaffs_GetBlockInfo(dev, blk);
5384                 state = bi->blockState;
5385
5386                 deleted = 0;
5387
5388                 /* For each chunk in each block that needs scanning.... */
5389                 foundChunksInBlock = 0;
5390                 for (c = dev->nChunksPerBlock - 1; c >= 0 &&
5391                      (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING ||
5392                       state == YAFFS_BLOCK_STATE_ALLOCATING); c--) {
5393                         /* Scan backwards...
5394                          * Read the tags and decide what to do
5395                          */
5396                         chunk = blk * dev->nChunksPerBlock + c;
5397
5398                         result = yaffs_ReadChunkWithTagsFromNAND(dev, chunk, NULL,
5399                                                         &tags);
5400
5401                         /* Let's have a good look at this chunk... */
5402
5403                         if (!tags.chunkUsed) {
5404                                 /* An unassigned chunk in the block.
5405                                  * If there are used chunks after this one, then
5406                                  * it is a chunk that was skipped due to failing the erased
5407                                  * check. Just skip it so that it can be deleted.
5408                                  * But, more typically, We get here when this is an unallocated
5409                                  * chunk and his means that either the block is empty or
5410                                  * this is the one being allocated from
5411                                  */
5412
5413                                 if(foundChunksInBlock)
5414                                 {
5415                                         /* This is a chunk that was skipped due to failing the erased check */
5416
5417                                 } else if (c == 0) {
5418                                         /* We're looking at the first chunk in the block so the block is unused */
5419                                         state = YAFFS_BLOCK_STATE_EMPTY;
5420                                         dev->nErasedBlocks++;
5421                                 } else {
5422                                         if (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING ||
5423                                             state == YAFFS_BLOCK_STATE_ALLOCATING) {
5424                                                 if(dev->sequenceNumber == bi->sequenceNumber) {
5425                                                         /* this is the block being allocated from */
5426
5427                                                         T(YAFFS_TRACE_SCAN,
5428                                                           (TSTR
5429                                                            (" Allocating from %d %d"
5430                                                             TENDSTR), blk, c));
5431
5432                                                         state = YAFFS_BLOCK_STATE_ALLOCATING;
5433                                                         dev->allocationBlock = blk;
5434                                                         dev->allocationPage = c;
5435                                                         dev->allocationBlockFinder = blk;
5436                                                 }
5437                                                 else {
5438                                                         /* This is a partially written block that is not
5439                                                          * the current allocation block. This block must have
5440                                                          * had a write failure, so set up for retirement.
5441                                                          */
5442
5443                                                          bi->needsRetiring = 1;
5444                                                          bi->gcPrioritise = 1;
5445
5446                                                          T(YAFFS_TRACE_ALWAYS,
5447                                                          (TSTR("Partially written block %d being set for retirement" TENDSTR),
5448                                                          blk));
5449                                                 }
5450
5451                                         }
5452
5453                                 }
5454
5455                                 dev->nFreeChunks++;
5456
5457                         } else if (tags.chunkId > 0) {
5458                                 /* chunkId > 0 so it is a data chunk... */
5459                                 unsigned int endpos;
5460                                 __u32 chunkBase =
5461                                     (tags.chunkId - 1) * dev->nDataBytesPerChunk;
5462
5463                                 foundChunksInBlock = 1;
5464
5465
5466                                 yaffs_SetChunkBit(dev, blk, c);
5467                                 bi->pagesInUse++;
5468
5469                                 in = yaffs_FindOrCreateObjectByNumber(dev,
5470                                                                       tags.
5471                                                                       objectId,
5472                                                                       YAFFS_OBJECT_TYPE_FILE);
5473                                 if (in->variantType == YAFFS_OBJECT_TYPE_FILE
5474                                     && chunkBase <
5475                                     in->variant.fileVariant.shrinkSize) {
5476                                         /* This has not been invalidated by a resize */
5477                                         yaffs_PutChunkIntoFile(in, tags.chunkId,
5478                                                                chunk, -1);
5479
5480                                         /* File size is calculated by looking at the data chunks if we have not
5481                                          * seen an object header yet. Stop this practice once we find an object header.
5482                                          */
5483                                         endpos =
5484                                             (tags.chunkId -
5485                                              1) * dev->nDataBytesPerChunk +
5486                                             tags.byteCount;
5487
5488                                         if (!in->valid &&       /* have not got an object header yet */
5489                                             in->variant.fileVariant.
5490                                             scannedFileSize < endpos) {
5491                                                 in->variant.fileVariant.
5492                                                     scannedFileSize = endpos;
5493                                                 in->variant.fileVariant.
5494                                                     fileSize =
5495                                                     in->variant.fileVariant.
5496                                                     scannedFileSize;
5497                                         }
5498
5499                                 } else {
5500                                         /* This chunk has been invalidated by a resize, so delete */
5501                                         yaffs_DeleteChunk(dev, chunk, 1, __LINE__);
5502
5503                                 }
5504                         } else {
5505                                 /* chunkId == 0, so it is an ObjectHeader.
5506                                  * Thus, we read in the object header and make the object
5507                                  */
5508                                 foundChunksInBlock = 1;
5509
5510                                 yaffs_SetChunkBit(dev, blk, c);
5511                                 bi->pagesInUse++;
5512
5513                                 oh = NULL;
5514                                 in = NULL;
5515
5516                                 if (tags.extraHeaderInfoAvailable) {
5517                                         in = yaffs_FindOrCreateObjectByNumber
5518                                             (dev, tags.objectId,
5519                                              tags.extraObjectType);
5520                                 }
5521
5522                                 if (!in ||
5523 #ifdef CONFIG_YAFFS_DISABLE_LAZY_LOAD
5524                                     !in->valid ||
5525 #endif
5526                                     tags.extraShadows ||
5527                                     (!in->valid &&
5528                                     (tags.objectId == YAFFS_OBJECTID_ROOT ||
5529                                      tags.objectId == YAFFS_OBJECTID_LOSTNFOUND))
5530                                     ) {
5531
5532                                         /* If we don't have  valid info then we need to read the chunk
5533                                          * TODO In future we can probably defer reading the chunk and
5534                                          * living with invalid data until needed.
5535                                          */
5536
5537                                         result = yaffs_ReadChunkWithTagsFromNAND(dev,
5538                                                                         chunk,
5539                                                                         chunkData,
5540                                                                         NULL);
5541
5542                                         oh = (yaffs_ObjectHeader *) chunkData;
5543
5544                                         if (!in)
5545                                                 in = yaffs_FindOrCreateObjectByNumber(dev, tags.objectId, oh->type);
5546
5547                                 }
5548
5549                                 if (!in) {
5550                                         /* TODO Hoosterman we have a problem! */
5551                                         T(YAFFS_TRACE_ERROR,
5552                                           (TSTR
5553                                            ("yaffs tragedy: Could not make object for object  %d  "
5554                                             "at chunk %d during scan"
5555                                             TENDSTR), tags.objectId, chunk));
5556
5557                                 }
5558
5559                                 if (in->valid) {
5560                                         /* We have already filled this one.
5561                                          * We have a duplicate that will be discarded, but
5562                                          * we first have to suck out resize info if it is a file.
5563                                          */
5564
5565                                         if ((in->variantType == YAFFS_OBJECT_TYPE_FILE) &&
5566                                              ((oh &&
5567                                                oh-> type == YAFFS_OBJECT_TYPE_FILE)||
5568                                               (tags.extraHeaderInfoAvailable  &&
5569                                                tags.extraObjectType == YAFFS_OBJECT_TYPE_FILE))
5570                                             ) {
5571                                                 __u32 thisSize =
5572                                                     (oh) ? oh->fileSize : tags.
5573                                                     extraFileLength;
5574                                                 __u32 parentObjectId =
5575                                                     (oh) ? oh->
5576                                                     parentObjectId : tags.
5577                                                     extraParentObjectId;
5578                                                 unsigned isShrink =
5579                                                     (oh) ? oh->isShrink : tags.
5580                                                     extraIsShrinkHeader;
5581
5582                                                 /* If it is deleted (unlinked at start also means deleted)
5583                                                  * we treat the file size as being zeroed at this point.
5584                                                  */
5585                                                 if (parentObjectId ==
5586                                                     YAFFS_OBJECTID_DELETED
5587                                                     || parentObjectId ==
5588                                                     YAFFS_OBJECTID_UNLINKED) {
5589                                                         thisSize = 0;
5590                                                         isShrink = 1;
5591                                                 }
5592
5593                                                 if (isShrink &&
5594                                                     in->variant.fileVariant.
5595                                                     shrinkSize > thisSize) {
5596                                                         in->variant.fileVariant.
5597                                                             shrinkSize =
5598                                                             thisSize;
5599                                                 }
5600
5601                                                 if (isShrink) {
5602                                                         bi->hasShrinkHeader = 1;
5603                                                 }
5604
5605                                         }
5606                                         /* Use existing - destroy this one. */
5607                                         yaffs_DeleteChunk(dev, chunk, 1, __LINE__);
5608
5609                                 }
5610
5611                                 if (!in->valid &&
5612                                     (tags.objectId == YAFFS_OBJECTID_ROOT ||
5613                                      tags.objectId ==
5614                                      YAFFS_OBJECTID_LOSTNFOUND)) {
5615                                         /* We only load some info, don't fiddle with directory structure */
5616                                         in->valid = 1;
5617
5618                                         if(oh) {
5619                                                 in->variantType = oh->type;
5620
5621                                                 in->yst_mode = oh->yst_mode;
5622 #ifdef CONFIG_YAFFS_WINCE
5623                                                 in->win_atime[0] = oh->win_atime[0];
5624                                                 in->win_ctime[0] = oh->win_ctime[0];
5625                                                 in->win_mtime[0] = oh->win_mtime[0];
5626                                                 in->win_atime[1] = oh->win_atime[1];
5627                                                 in->win_ctime[1] = oh->win_ctime[1];
5628                                                 in->win_mtime[1] = oh->win_mtime[1];
5629 #else
5630                                                 in->yst_uid = oh->yst_uid;
5631                                                 in->yst_gid = oh->yst_gid;
5632                                                 in->yst_atime = oh->yst_atime;
5633                                                 in->yst_mtime = oh->yst_mtime;
5634                                                 in->yst_ctime = oh->yst_ctime;
5635                                                 in->yst_rdev = oh->yst_rdev;
5636
5637 #endif
5638                                         } else {
5639                                                 in->variantType = tags.extraObjectType;
5640                                                 in->lazyLoaded = 1;
5641                                         }
5642
5643                                         in->chunkId = chunk;
5644
5645                                 } else if (!in->valid) {
5646                                         /* we need to load this info */
5647
5648                                         in->valid = 1;
5649                                         in->chunkId = chunk;
5650
5651                                         if(oh) {
5652                                                 in->variantType = oh->type;
5653
5654                                                 in->yst_mode = oh->yst_mode;
5655 #ifdef CONFIG_YAFFS_WINCE
5656                                                 in->win_atime[0] = oh->win_atime[0];
5657                                                 in->win_ctime[0] = oh->win_ctime[0];
5658                                                 in->win_mtime[0] = oh->win_mtime[0];
5659                                                 in->win_atime[1] = oh->win_atime[1];
5660                                                 in->win_ctime[1] = oh->win_ctime[1];
5661                                                 in->win_mtime[1] = oh->win_mtime[1];
5662 #else
5663                                                 in->yst_uid = oh->yst_uid;
5664                                                 in->yst_gid = oh->yst_gid;
5665                                                 in->yst_atime = oh->yst_atime;
5666                                                 in->yst_mtime = oh->yst_mtime;
5667                                                 in->yst_ctime = oh->yst_ctime;
5668                                                 in->yst_rdev = oh->yst_rdev;
5669 #endif
5670
5671                                                 if (oh->shadowsObject > 0)
5672                                                         yaffs_HandleShadowedObject(dev,
5673                                                                            oh->
5674                                                                            shadowsObject,
5675                                                                            1);
5676
5677
5678                                                 yaffs_SetObjectName(in, oh->name);
5679                                                 parent =
5680                                                     yaffs_FindOrCreateObjectByNumber
5681                                                         (dev, oh->parentObjectId,
5682                                                          YAFFS_OBJECT_TYPE_DIRECTORY);
5683
5684                                                  fileSize = oh->fileSize;
5685                                                  isShrink = oh->isShrink;
5686                                                  equivalentObjectId = oh->equivalentObjectId;
5687
5688                                         }
5689                                         else {
5690                                                 in->variantType = tags.extraObjectType;
5691                                                 parent =
5692                                                     yaffs_FindOrCreateObjectByNumber
5693                                                         (dev, tags.extraParentObjectId,
5694                                                          YAFFS_OBJECT_TYPE_DIRECTORY);
5695                                                  fileSize = tags.extraFileLength;
5696                                                  isShrink = tags.extraIsShrinkHeader;
5697                                                  equivalentObjectId = tags.extraEquivalentObjectId;
5698                                                 in->lazyLoaded = 1;
5699
5700                                         }
5701                                         in->dirty = 0;
5702
5703                                         /* directory stuff...
5704                                          * hook up to parent
5705                                          */
5706
5707                                         if (parent->variantType ==
5708                                             YAFFS_OBJECT_TYPE_UNKNOWN) {
5709                                                 /* Set up as a directory */
5710                                                 parent->variantType =
5711                                                     YAFFS_OBJECT_TYPE_DIRECTORY;
5712                                                 INIT_LIST_HEAD(&parent->variant.
5713                                                                directoryVariant.
5714                                                                children);
5715                                         } else if (parent->variantType !=
5716                                                    YAFFS_OBJECT_TYPE_DIRECTORY)
5717                                         {
5718                                                 /* Hoosterman, another problem....
5719                                                  * We're trying to use a non-directory as a directory
5720                                                  */
5721
5722                                                 T(YAFFS_TRACE_ERROR,
5723                                                   (TSTR
5724                                                    ("yaffs tragedy: attempting to use non-directory as"
5725                                                     " a directory in scan. Put in lost+found."
5726                                                     TENDSTR)));
5727                                                 parent = dev->lostNFoundDir;
5728                                         }
5729
5730                                         yaffs_AddObjectToDirectory(parent, in);
5731
5732                                         itsUnlinked = (parent == dev->deletedDir) ||
5733                                                       (parent == dev->unlinkedDir);
5734
5735                                         if (isShrink) {
5736                                                 /* Mark the block as having a shrinkHeader */
5737                                                 bi->hasShrinkHeader = 1;
5738                                         }
5739
5740                                         /* Note re hardlinks.
5741                                          * Since we might scan a hardlink before its equivalent object is scanned
5742                                          * we put them all in a list.
5743                                          * After scanning is complete, we should have all the objects, so we run
5744                                          * through this list and fix up all the chains.
5745                                          */
5746
5747                                         switch (in->variantType) {
5748                                         case YAFFS_OBJECT_TYPE_UNKNOWN:
5749                                                 /* Todo got a problem */
5750                                                 break;
5751                                         case YAFFS_OBJECT_TYPE_FILE:
5752
5753                                                 if (in->variant.fileVariant.
5754                                                     scannedFileSize < fileSize) {
5755                                                         /* This covers the case where the file size is greater
5756                                                          * than where the data is
5757                                                          * This will happen if the file is resized to be larger
5758                                                          * than its current data extents.
5759                                                          */
5760                                                         in->variant.fileVariant.fileSize = fileSize;
5761                                                         in->variant.fileVariant.scannedFileSize =
5762                                                             in->variant.fileVariant.fileSize;
5763                                                 }
5764
5765                                                 if (isShrink &&
5766                                                     in->variant.fileVariant.shrinkSize > fileSize) {
5767                                                         in->variant.fileVariant.shrinkSize = fileSize;
5768                                                 }
5769
5770                                                 break;
5771                                         case YAFFS_OBJECT_TYPE_HARDLINK:
5772                                                 if(!itsUnlinked) {
5773                                                   in->variant.hardLinkVariant.equivalentObjectId =
5774                                                     equivalentObjectId;
5775                                                   in->hardLinks.next =
5776                                                     (struct list_head *) hardList;
5777                                                   hardList = in;
5778                                                 }
5779                                                 break;
5780                                         case YAFFS_OBJECT_TYPE_DIRECTORY:
5781                                                 /* Do nothing */
5782                                                 break;
5783                                         case YAFFS_OBJECT_TYPE_SPECIAL:
5784                                                 /* Do nothing */
5785                                                 break;
5786                                         case YAFFS_OBJECT_TYPE_SYMLINK:
5787                                                 if(oh)
5788                                                    in->variant.symLinkVariant.alias =
5789                                                     yaffs_CloneString(oh->
5790                                                                       alias);
5791                                                 break;
5792                                         }
5793
5794                                 }
5795                         }
5796                 }
5797
5798                 if (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING) {
5799                         /* If we got this far while scanning, then the block is fully allocated. */
5800                         state = YAFFS_BLOCK_STATE_FULL;
5801                 }
5802
5803                 bi->blockState = state;
5804
5805                 /* Now let's see if it was dirty */
5806                 if (bi->pagesInUse == 0 &&
5807                     !bi->hasShrinkHeader &&
5808                     bi->blockState == YAFFS_BLOCK_STATE_FULL) {
5809                         yaffs_BlockBecameDirty(dev, blk);
5810                 }
5811
5812         }
5813
5814         if (altBlockIndex)
5815                 YFREE_ALT(blockIndex);
5816         else
5817                 YFREE(blockIndex);
5818
5819         /* Ok, we've done all the scanning.
5820          * Fix up the hard link chains.
5821          * We should now have scanned all the objects, now it's time to add these
5822          * hardlinks.
5823          */
5824         yaffs_HardlinkFixup(dev,hardList);
5825
5826
5827         /*
5828         *  Sort out state of unlinked and deleted objects.
5829         */
5830         {
5831                 struct list_head *i;
5832                 struct list_head *n;
5833
5834                 yaffs_Object *l;
5835
5836                 /* Soft delete all the unlinked files */
5837                 list_for_each_safe(i, n,
5838                                    &dev->unlinkedDir->variant.directoryVariant.
5839                                    children) {
5840                         if (i) {
5841                                 l = list_entry(i, yaffs_Object, siblings);
5842                                 yaffs_DestroyObject(l);
5843                         }
5844                 }
5845
5846                 /* Soft delete all the deletedDir files */
5847                 list_for_each_safe(i, n,
5848                                    &dev->deletedDir->variant.directoryVariant.
5849                                    children) {
5850                         if (i) {
5851                                 l = list_entry(i, yaffs_Object, siblings);
5852                                 yaffs_DestroyObject(l);
5853
5854                         }
5855                 }
5856         }
5857
5858         yaffs_ReleaseTempBuffer(dev, chunkData, __LINE__);
5859
5860         T(YAFFS_TRACE_SCAN, (TSTR("yaffs_ScanBackwards ends" TENDSTR)));
5861
5862         return YAFFS_OK;
5863 }
5864
5865 /*------------------------------  Directory Functions ----------------------------- */
5866
5867 static void yaffs_RemoveObjectFromDirectory(yaffs_Object * obj)
5868 {
5869         yaffs_Device *dev = obj->myDev;
5870
5871         if(dev && dev->removeObjectCallback)
5872                 dev->removeObjectCallback(obj);
5873
5874         list_del_init(&obj->siblings);
5875         obj->parent = NULL;
5876 }
5877
5878
5879 static void yaffs_AddObjectToDirectory(yaffs_Object * directory,
5880                                        yaffs_Object * obj)
5881 {
5882
5883         if (!directory) {
5884                 T(YAFFS_TRACE_ALWAYS,
5885                   (TSTR
5886                    ("tragedy: Trying to add an object to a null pointer directory"
5887                     TENDSTR)));
5888                 YBUG();
5889         }
5890         if (directory->variantType != YAFFS_OBJECT_TYPE_DIRECTORY) {
5891                 T(YAFFS_TRACE_ALWAYS,
5892                   (TSTR
5893                    ("tragedy: Trying to add an object to a non-directory"
5894                     TENDSTR)));
5895                 YBUG();
5896         }
5897
5898         if (obj->siblings.prev == NULL) {
5899                 /* Not initialised */
5900                 INIT_LIST_HEAD(&obj->siblings);
5901
5902         } else if (!list_empty(&obj->siblings)) {
5903                 /* If it is holed up somewhere else, un hook it */
5904                 yaffs_RemoveObjectFromDirectory(obj);
5905         }
5906         /* Now add it */
5907         list_add(&obj->siblings, &directory->variant.directoryVariant.children);
5908         obj->parent = directory;
5909
5910         if (directory == obj->myDev->unlinkedDir
5911             || directory == obj->myDev->deletedDir) {
5912                 obj->unlinked = 1;
5913                 obj->myDev->nUnlinkedFiles++;
5914                 obj->renameAllowed = 0;
5915         }
5916 }
5917
5918 yaffs_Object *yaffs_FindObjectByName(yaffs_Object * directory,
5919                                      const YCHAR * name)
5920 {
5921         int sum;
5922
5923         struct list_head *i;
5924         YCHAR buffer[YAFFS_MAX_NAME_LENGTH + 1];
5925
5926         yaffs_Object *l;
5927
5928         if (!name) {
5929                 return NULL;
5930         }
5931
5932         if (!directory) {
5933                 T(YAFFS_TRACE_ALWAYS,
5934                   (TSTR
5935                    ("tragedy: yaffs_FindObjectByName: null pointer directory"
5936                     TENDSTR)));
5937                 YBUG();
5938         }
5939         if (directory->variantType != YAFFS_OBJECT_TYPE_DIRECTORY) {
5940                 T(YAFFS_TRACE_ALWAYS,
5941                   (TSTR
5942                    ("tragedy: yaffs_FindObjectByName: non-directory" TENDSTR)));
5943                 YBUG();
5944         }
5945
5946         sum = yaffs_CalcNameSum(name);
5947
5948         list_for_each(i, &directory->variant.directoryVariant.children) {
5949                 if (i) {
5950                         l = list_entry(i, yaffs_Object, siblings);
5951
5952                         yaffs_CheckObjectDetailsLoaded(l);
5953
5954                         /* Special case for lost-n-found */
5955                         if (l->objectId == YAFFS_OBJECTID_LOSTNFOUND) {
5956                                 if (yaffs_strcmp(name, YAFFS_LOSTNFOUND_NAME) == 0) {
5957                                         return l;
5958                                 }
5959                         } else if (yaffs_SumCompare(l->sum, sum) || l->chunkId <= 0)
5960                         {
5961                                 /* LostnFound cunk called Objxxx
5962                                  * Do a real check
5963                                  */
5964                                 yaffs_GetObjectName(l, buffer,
5965                                                     YAFFS_MAX_NAME_LENGTH);
5966                                 if (yaffs_strcmp(name, buffer) == 0) {
5967                                         return l;
5968                                 }
5969
5970                         }
5971                 }
5972         }
5973
5974         return NULL;
5975 }
5976
5977
5978 #if 0
5979 int yaffs_ApplyToDirectoryChildren(yaffs_Object * theDir,
5980                                    int (*fn) (yaffs_Object *))
5981 {
5982         struct list_head *i;
5983         yaffs_Object *l;
5984
5985         if (!theDir) {
5986                 T(YAFFS_TRACE_ALWAYS,
5987                   (TSTR
5988                    ("tragedy: yaffs_FindObjectByName: null pointer directory"
5989                     TENDSTR)));
5990                 YBUG();
5991         }
5992         if (theDir->variantType != YAFFS_OBJECT_TYPE_DIRECTORY) {
5993                 T(YAFFS_TRACE_ALWAYS,
5994                   (TSTR
5995                    ("tragedy: yaffs_FindObjectByName: non-directory" TENDSTR)));
5996                 YBUG();
5997         }
5998
5999         list_for_each(i, &theDir->variant.directoryVariant.children) {
6000                 if (i) {
6001                         l = list_entry(i, yaffs_Object, siblings);
6002                         if (l && !fn(l)) {
6003                                 return YAFFS_FAIL;
6004                         }
6005                 }
6006         }
6007
6008         return YAFFS_OK;
6009
6010 }
6011 #endif
6012
6013 /* GetEquivalentObject dereferences any hard links to get to the
6014  * actual object.
6015  */
6016
6017 yaffs_Object *yaffs_GetEquivalentObject(yaffs_Object * obj)
6018 {
6019         if (obj && obj->variantType == YAFFS_OBJECT_TYPE_HARDLINK) {
6020                 /* We want the object id of the equivalent object, not this one */
6021                 obj = obj->variant.hardLinkVariant.equivalentObject;
6022         }
6023         return obj;
6024
6025 }
6026
6027 int yaffs_GetObjectName(yaffs_Object * obj, YCHAR * name, int buffSize)
6028 {
6029         memset(name, 0, buffSize * sizeof(YCHAR));
6030
6031         yaffs_CheckObjectDetailsLoaded(obj);
6032
6033         if (obj->objectId == YAFFS_OBJECTID_LOSTNFOUND) {
6034                 yaffs_strncpy(name, YAFFS_LOSTNFOUND_NAME, buffSize - 1);
6035         } else if (obj->chunkId <= 0) {
6036                 YCHAR locName[20];
6037                 /* make up a name */
6038                 yaffs_sprintf(locName, _Y("%s%d"), YAFFS_LOSTNFOUND_PREFIX,
6039                               obj->objectId);
6040                 yaffs_strncpy(name, locName, buffSize - 1);
6041
6042         }
6043 #ifdef CONFIG_YAFFS_SHORT_NAMES_IN_RAM
6044         else if (obj->shortName[0]) {
6045                 yaffs_strcpy(name, obj->shortName);
6046         }
6047 #endif
6048         else {
6049                 int result;
6050                 __u8 *buffer = yaffs_GetTempBuffer(obj->myDev, __LINE__);
6051
6052                 yaffs_ObjectHeader *oh = (yaffs_ObjectHeader *) buffer;
6053
6054                 memset(buffer, 0, obj->myDev->nDataBytesPerChunk);
6055
6056                 if (obj->chunkId >= 0) {
6057                         result = yaffs_ReadChunkWithTagsFromNAND(obj->myDev,
6058                                                         obj->chunkId, buffer,
6059                                                         NULL);
6060                 }
6061                 yaffs_strncpy(name, oh->name, buffSize - 1);
6062
6063                 yaffs_ReleaseTempBuffer(obj->myDev, buffer, __LINE__);
6064         }
6065
6066         return yaffs_strlen(name);
6067 }
6068
6069 int yaffs_GetObjectFileLength(yaffs_Object * obj)
6070 {
6071
6072         /* Dereference any hard linking */
6073         obj = yaffs_GetEquivalentObject(obj);
6074
6075         if (obj->variantType == YAFFS_OBJECT_TYPE_FILE) {
6076                 return obj->variant.fileVariant.fileSize;
6077         }
6078         if (obj->variantType == YAFFS_OBJECT_TYPE_SYMLINK) {
6079                 return yaffs_strlen(obj->variant.symLinkVariant.alias);
6080         } else {
6081                 /* Only a directory should drop through to here */
6082                 return obj->myDev->nDataBytesPerChunk;
6083         }
6084 }
6085
6086 int yaffs_GetObjectLinkCount(yaffs_Object * obj)
6087 {
6088         int count = 0;
6089         struct list_head *i;
6090
6091         if (!obj->unlinked) {
6092                 count++;        /* the object itself */
6093         }
6094         list_for_each(i, &obj->hardLinks) {
6095                 count++;        /* add the hard links; */
6096         }
6097         return count;
6098
6099 }
6100
6101 int yaffs_GetObjectInode(yaffs_Object * obj)
6102 {
6103         obj = yaffs_GetEquivalentObject(obj);
6104
6105         return obj->objectId;
6106 }
6107
6108 unsigned yaffs_GetObjectType(yaffs_Object * obj)
6109 {
6110         obj = yaffs_GetEquivalentObject(obj);
6111
6112         switch (obj->variantType) {
6113         case YAFFS_OBJECT_TYPE_FILE:
6114                 return DT_REG;
6115                 break;
6116         case YAFFS_OBJECT_TYPE_DIRECTORY:
6117                 return DT_DIR;
6118                 break;
6119         case YAFFS_OBJECT_TYPE_SYMLINK:
6120                 return DT_LNK;
6121                 break;
6122         case YAFFS_OBJECT_TYPE_HARDLINK:
6123                 return DT_REG;
6124                 break;
6125         case YAFFS_OBJECT_TYPE_SPECIAL:
6126                 if (S_ISFIFO(obj->yst_mode))
6127                         return DT_FIFO;
6128                 if (S_ISCHR(obj->yst_mode))
6129                         return DT_CHR;
6130                 if (S_ISBLK(obj->yst_mode))
6131                         return DT_BLK;
6132                 if (S_ISSOCK(obj->yst_mode))
6133                         return DT_SOCK;
6134         default:
6135                 return DT_REG;
6136                 break;
6137         }
6138 }
6139
6140 YCHAR *yaffs_GetSymlinkAlias(yaffs_Object * obj)
6141 {
6142         obj = yaffs_GetEquivalentObject(obj);
6143         if (obj->variantType == YAFFS_OBJECT_TYPE_SYMLINK) {
6144                 return yaffs_CloneString(obj->variant.symLinkVariant.alias);
6145         } else {
6146                 return yaffs_CloneString(_Y(""));
6147         }
6148 }
6149
6150 #ifndef CONFIG_YAFFS_WINCE
6151
6152 int yaffs_SetAttributes(yaffs_Object * obj, struct iattr *attr)
6153 {
6154         unsigned int valid = attr->ia_valid;
6155
6156         if (valid & ATTR_MODE)
6157                 obj->yst_mode = attr->ia_mode;
6158         if (valid & ATTR_UID)
6159                 obj->yst_uid = attr->ia_uid;
6160         if (valid & ATTR_GID)
6161                 obj->yst_gid = attr->ia_gid;
6162
6163         if (valid & ATTR_ATIME)
6164                 obj->yst_atime = Y_TIME_CONVERT(attr->ia_atime);
6165         if (valid & ATTR_CTIME)
6166                 obj->yst_ctime = Y_TIME_CONVERT(attr->ia_ctime);
6167         if (valid & ATTR_MTIME)
6168                 obj->yst_mtime = Y_TIME_CONVERT(attr->ia_mtime);
6169
6170         if (valid & ATTR_SIZE)
6171                 yaffs_ResizeFile(obj, attr->ia_size);
6172
6173         yaffs_UpdateObjectHeader(obj, NULL, 1, 0, 0);
6174
6175         return YAFFS_OK;
6176
6177 }
6178 int yaffs_GetAttributes(yaffs_Object * obj, struct iattr *attr)
6179 {
6180         unsigned int valid = 0;
6181
6182         attr->ia_mode = obj->yst_mode;
6183         valid |= ATTR_MODE;
6184         attr->ia_uid = obj->yst_uid;
6185         valid |= ATTR_UID;
6186         attr->ia_gid = obj->yst_gid;
6187         valid |= ATTR_GID;
6188
6189         Y_TIME_CONVERT(attr->ia_atime) = obj->yst_atime;
6190         valid |= ATTR_ATIME;
6191         Y_TIME_CONVERT(attr->ia_ctime) = obj->yst_ctime;
6192         valid |= ATTR_CTIME;
6193         Y_TIME_CONVERT(attr->ia_mtime) = obj->yst_mtime;
6194         valid |= ATTR_MTIME;
6195
6196         attr->ia_size = yaffs_GetFileSize(obj);
6197         valid |= ATTR_SIZE;
6198
6199         attr->ia_valid = valid;
6200
6201         return YAFFS_OK;
6202
6203 }
6204
6205 #endif
6206
6207 #if 0
6208 int yaffs_DumpObject(yaffs_Object * obj)
6209 {
6210         YCHAR name[257];
6211
6212         yaffs_GetObjectName(obj, name, 256);
6213
6214         T(YAFFS_TRACE_ALWAYS,
6215           (TSTR
6216            ("Object %d, inode %d \"%s\"\n dirty %d valid %d serial %d sum %d"
6217             " chunk %d type %d size %d\n"
6218             TENDSTR), obj->objectId, yaffs_GetObjectInode(obj), name,
6219            obj->dirty, obj->valid, obj->serial, obj->sum, obj->chunkId,
6220            yaffs_GetObjectType(obj), yaffs_GetObjectFileLength(obj)));
6221
6222         return YAFFS_OK;
6223 }
6224 #endif
6225
6226 /*---------------------------- Initialisation code -------------------------------------- */
6227
6228 static int yaffs_CheckDevFunctions(const yaffs_Device * dev)
6229 {
6230
6231         /* Common functions, gotta have */
6232         if (!dev->eraseBlockInNAND || !dev->initialiseNAND)
6233                 return 0;
6234
6235 #ifdef CONFIG_YAFFS_YAFFS2
6236
6237         /* Can use the "with tags" style interface for yaffs1 or yaffs2 */
6238         if (dev->writeChunkWithTagsToNAND &&
6239             dev->readChunkWithTagsFromNAND &&
6240             !dev->writeChunkToNAND &&
6241             !dev->readChunkFromNAND &&
6242             dev->markNANDBlockBad && dev->queryNANDBlock)
6243                 return 1;
6244 #endif
6245
6246         /* Can use the "spare" style interface for yaffs1 */
6247         if (!dev->isYaffs2 &&
6248             !dev->writeChunkWithTagsToNAND &&
6249             !dev->readChunkWithTagsFromNAND &&
6250             dev->writeChunkToNAND &&
6251             dev->readChunkFromNAND &&
6252             !dev->markNANDBlockBad && !dev->queryNANDBlock)
6253                 return 1;
6254
6255         return 0;               /* bad */
6256 }
6257
6258
6259 static void yaffs_CreateInitialDirectories(yaffs_Device *dev)
6260 {
6261         /* Initialise the unlinked, deleted, root and lost and found directories */
6262
6263         dev->lostNFoundDir = dev->rootDir =  NULL;
6264         dev->unlinkedDir = dev->deletedDir = NULL;
6265
6266         dev->unlinkedDir =
6267             yaffs_CreateFakeDirectory(dev, YAFFS_OBJECTID_UNLINKED, S_IFDIR);
6268         dev->deletedDir =
6269             yaffs_CreateFakeDirectory(dev, YAFFS_OBJECTID_DELETED, S_IFDIR);
6270
6271         dev->rootDir =
6272             yaffs_CreateFakeDirectory(dev, YAFFS_OBJECTID_ROOT,
6273                                       YAFFS_ROOT_MODE | S_IFDIR);
6274         dev->lostNFoundDir =
6275             yaffs_CreateFakeDirectory(dev, YAFFS_OBJECTID_LOSTNFOUND,
6276                                       YAFFS_LOSTNFOUND_MODE | S_IFDIR);
6277         yaffs_AddObjectToDirectory(dev->rootDir, dev->lostNFoundDir);
6278 }
6279
6280 int yaffs_GutsInitialise(yaffs_Device * dev)
6281 {
6282         unsigned x;
6283         int bits;
6284
6285         T(YAFFS_TRACE_TRACING, (TSTR("yaffs: yaffs_GutsInitialise()" TENDSTR)));
6286
6287         /* Check stuff that must be set */
6288
6289         if (!dev) {
6290                 T(YAFFS_TRACE_ALWAYS, (TSTR("yaffs: Need a device" TENDSTR)));
6291                 return YAFFS_FAIL;
6292         }
6293
6294         dev->internalStartBlock = dev->startBlock;
6295         dev->internalEndBlock = dev->endBlock;
6296         dev->blockOffset = 0;
6297         dev->chunkOffset = 0;
6298         dev->nFreeChunks = 0;
6299
6300         if (dev->startBlock == 0) {
6301                 dev->internalStartBlock = dev->startBlock + 1;
6302                 dev->internalEndBlock = dev->endBlock + 1;
6303                 dev->blockOffset = 1;
6304                 dev->chunkOffset = dev->nChunksPerBlock;
6305         }
6306
6307         /* Check geometry parameters. */
6308
6309         if ((dev->isYaffs2 && dev->nDataBytesPerChunk < 1024) ||
6310             (!dev->isYaffs2 && dev->nDataBytesPerChunk != 512) ||
6311              dev->nChunksPerBlock < 2 ||
6312              dev->nReservedBlocks < 2 ||
6313              dev->internalStartBlock <= 0 ||
6314              dev->internalEndBlock <= 0 ||
6315              dev->internalEndBlock <= (dev->internalStartBlock + dev->nReservedBlocks + 2)      // otherwise it is too small
6316             ) {
6317                 T(YAFFS_TRACE_ALWAYS,
6318                   (TSTR
6319                    ("yaffs: NAND geometry problems: chunk size %d, type is yaffs%s "
6320                     TENDSTR), dev->nDataBytesPerChunk, dev->isYaffs2 ? "2" : ""));
6321                 return YAFFS_FAIL;
6322         }
6323
6324         if (yaffs_InitialiseNAND(dev) != YAFFS_OK) {
6325                 T(YAFFS_TRACE_ALWAYS,
6326                   (TSTR("yaffs: InitialiseNAND failed" TENDSTR)));
6327                 return YAFFS_FAIL;
6328         }
6329
6330         /* Got the right mix of functions? */
6331         if (!yaffs_CheckDevFunctions(dev)) {
6332                 /* Function missing */
6333                 T(YAFFS_TRACE_ALWAYS,
6334                   (TSTR
6335                    ("yaffs: device function(s) missing or wrong\n" TENDSTR)));
6336
6337                 return YAFFS_FAIL;
6338         }
6339
6340         /* This is really a compilation check. */
6341         if (!yaffs_CheckStructures()) {
6342                 T(YAFFS_TRACE_ALWAYS,
6343                   (TSTR("yaffs_CheckStructures failed\n" TENDSTR)));
6344                 return YAFFS_FAIL;
6345         }
6346
6347         if (dev->isMounted) {
6348                 T(YAFFS_TRACE_ALWAYS,
6349                   (TSTR("yaffs: device already mounted\n" TENDSTR)));
6350                 return YAFFS_FAIL;
6351         }
6352
6353         /* Finished with most checks. One or two more checks happen later on too. */
6354
6355         dev->isMounted = 1;
6356
6357
6358
6359         /* OK now calculate a few things for the device */
6360
6361         /*
6362          *  Calculate all the chunk size manipulation numbers:
6363          */
6364          /* Start off assuming it is a power of 2 */
6365          dev->chunkShift = ShiftDiv(dev->nDataBytesPerChunk);
6366          dev->chunkMask = (1<<dev->chunkShift) - 1;
6367
6368          if(dev->nDataBytesPerChunk == (dev->chunkMask + 1)){
6369                 /* Yes it is a power of 2, disable crumbs */
6370                 dev->crumbMask = 0;
6371                 dev->crumbShift = 0;
6372                 dev->crumbsPerChunk = 0;
6373          } else {
6374                 /* Not a power of 2, use crumbs instead */
6375                 dev->crumbShift = ShiftDiv(sizeof(yaffs_PackedTags2TagsPart));
6376                 dev->crumbMask = (1<<dev->crumbShift)-1;
6377                 dev->crumbsPerChunk = dev->nDataBytesPerChunk/(1 << dev->crumbShift);
6378                 dev->chunkShift = 0;
6379                 dev->chunkMask = 0;
6380         }
6381
6382
6383         /*
6384          * Calculate chunkGroupBits.
6385          * We need to find the next power of 2 > than internalEndBlock
6386          */
6387
6388         x = dev->nChunksPerBlock * (dev->internalEndBlock + 1);
6389
6390         bits = ShiftsGE(x);
6391
6392         /* Set up tnode width if wide tnodes are enabled. */
6393         if(!dev->wideTnodesDisabled){
6394                 /* bits must be even so that we end up with 32-bit words */
6395                 if(bits & 1)
6396                         bits++;
6397                 if(bits < 16)
6398                         dev->tnodeWidth = 16;
6399                 else
6400                         dev->tnodeWidth = bits;
6401         }
6402         else
6403                 dev->tnodeWidth = 16;
6404
6405         dev->tnodeMask = (1<<dev->tnodeWidth)-1;
6406
6407         /* Level0 Tnodes are 16 bits or wider (if wide tnodes are enabled),
6408          * so if the bitwidth of the
6409          * chunk range we're using is greater than 16 we need
6410          * to figure out chunk shift and chunkGroupSize
6411          */
6412
6413         if (bits <= dev->tnodeWidth)
6414                 dev->chunkGroupBits = 0;
6415         else
6416                 dev->chunkGroupBits = bits - dev->tnodeWidth;
6417
6418
6419         dev->chunkGroupSize = 1 << dev->chunkGroupBits;
6420
6421         if (dev->nChunksPerBlock < dev->chunkGroupSize) {
6422                 /* We have a problem because the soft delete won't work if
6423                  * the chunk group size > chunks per block.
6424                  * This can be remedied by using larger "virtual blocks".
6425                  */
6426                 T(YAFFS_TRACE_ALWAYS,
6427                   (TSTR("yaffs: chunk group too large\n" TENDSTR)));
6428
6429                 return YAFFS_FAIL;
6430         }
6431
6432         /* OK, we've finished verifying the device, lets continue with initialisation */
6433
6434         /* More device initialisation */
6435         dev->garbageCollections = 0;
6436         dev->passiveGarbageCollections = 0;
6437         dev->currentDirtyChecker = 0;
6438         dev->bufferedBlock = -1;
6439         dev->doingBufferedBlockRewrite = 0;
6440         dev->nDeletedFiles = 0;
6441         dev->nBackgroundDeletions = 0;
6442         dev->nUnlinkedFiles = 0;
6443         dev->eccFixed = 0;
6444         dev->eccUnfixed = 0;
6445         dev->tagsEccFixed = 0;
6446         dev->tagsEccUnfixed = 0;
6447         dev->nErasureFailures = 0;
6448         dev->nErasedBlocks = 0;
6449         dev->isDoingGC = 0;
6450         dev->hasPendingPrioritisedGCs = 1; /* Assume the worst for now, will get fixed on first GC */
6451
6452         /* Initialise temporary buffers and caches. */
6453         {
6454                 int i;
6455                 for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
6456                         dev->tempBuffer[i].line = 0;    /* not in use */
6457                         dev->tempBuffer[i].buffer =
6458                             YMALLOC_DMA(dev->nDataBytesPerChunk);
6459                 }
6460         }
6461
6462         if (dev->nShortOpCaches > 0) {
6463                 int i;
6464
6465                 if (dev->nShortOpCaches > YAFFS_MAX_SHORT_OP_CACHES) {
6466                         dev->nShortOpCaches = YAFFS_MAX_SHORT_OP_CACHES;
6467                 }
6468
6469                 dev->srCache =
6470                     YMALLOC(dev->nShortOpCaches * sizeof(yaffs_ChunkCache));
6471
6472                 for (i = 0; i < dev->nShortOpCaches; i++) {
6473                         dev->srCache[i].object = NULL;
6474                         dev->srCache[i].lastUse = 0;
6475                         dev->srCache[i].dirty = 0;
6476                         dev->srCache[i].data = YMALLOC_DMA(dev->nDataBytesPerChunk);
6477                 }
6478                 dev->srLastUse = 0;
6479         }
6480
6481         dev->cacheHits = 0;
6482
6483         dev->gcCleanupList = YMALLOC(dev->nChunksPerBlock * sizeof(__u32));
6484
6485         if (dev->isYaffs2) {
6486                 dev->useHeaderFileSize = 1;
6487         }
6488
6489         yaffs_InitialiseBlocks(dev);
6490         yaffs_InitialiseTnodes(dev);
6491         yaffs_InitialiseObjects(dev);
6492
6493         yaffs_CreateInitialDirectories(dev);
6494
6495
6496         /* Now scan the flash. */
6497         if (dev->isYaffs2) {
6498                 if(yaffs_CheckpointRestore(dev)) {
6499                         T(YAFFS_TRACE_ALWAYS,
6500                           (TSTR("yaffs: restored from checkpoint" TENDSTR)));
6501                 } else {
6502
6503                         /* Clean up the mess caused by an aborted checkpoint load
6504                          * and scan backwards.
6505                          */
6506                         yaffs_DeinitialiseBlocks(dev);
6507                         yaffs_DeinitialiseTnodes(dev);
6508                         yaffs_DeinitialiseObjects(dev);
6509                         yaffs_InitialiseBlocks(dev);
6510                         yaffs_InitialiseTnodes(dev);
6511                         yaffs_InitialiseObjects(dev);
6512                         yaffs_CreateInitialDirectories(dev);
6513
6514                         yaffs_ScanBackwards(dev);
6515                 }
6516         }else
6517                 yaffs_Scan(dev);
6518
6519         /* Zero out stats */
6520         dev->nPageReads = 0;
6521         dev->nPageWrites = 0;
6522         dev->nBlockErasures = 0;
6523         dev->nGCCopies = 0;
6524         dev->nRetriedWrites = 0;
6525
6526         dev->nRetiredBlocks = 0;
6527
6528         yaffs_VerifyFreeChunks(dev);
6529
6530         T(YAFFS_TRACE_TRACING,
6531           (TSTR("yaffs: yaffs_GutsInitialise() done.\n" TENDSTR)));
6532         return YAFFS_OK;
6533
6534 }
6535
6536 void yaffs_Deinitialise(yaffs_Device * dev)
6537 {
6538         if (dev->isMounted) {
6539                 int i;
6540
6541                 yaffs_DeinitialiseBlocks(dev);
6542                 yaffs_DeinitialiseTnodes(dev);
6543                 yaffs_DeinitialiseObjects(dev);
6544                 if (dev->nShortOpCaches > 0) {
6545
6546                         for (i = 0; i < dev->nShortOpCaches; i++) {
6547                                 YFREE(dev->srCache[i].data);
6548                         }
6549
6550                         YFREE(dev->srCache);
6551                 }
6552
6553                 YFREE(dev->gcCleanupList);
6554
6555                 for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
6556                         YFREE(dev->tempBuffer[i].buffer);
6557                 }
6558
6559                 dev->isMounted = 0;
6560         }
6561
6562 }
6563
6564 static int yaffs_CountFreeChunks(yaffs_Device * dev)
6565 {
6566         int nFree;
6567         int b;
6568
6569         yaffs_BlockInfo *blk;
6570
6571         for (nFree = 0, b = dev->internalStartBlock; b <= dev->internalEndBlock;
6572              b++) {
6573                 blk = yaffs_GetBlockInfo(dev, b);
6574
6575                 switch (blk->blockState) {
6576                 case YAFFS_BLOCK_STATE_EMPTY:
6577                 case YAFFS_BLOCK_STATE_ALLOCATING:
6578                 case YAFFS_BLOCK_STATE_COLLECTING:
6579                 case YAFFS_BLOCK_STATE_FULL:
6580                         nFree +=
6581                             (dev->nChunksPerBlock - blk->pagesInUse +
6582                              blk->softDeletions);
6583                         break;
6584                 default:
6585                         break;
6586                 }
6587
6588         }
6589
6590         return nFree;
6591 }
6592
6593 int yaffs_GetNumberOfFreeChunks(yaffs_Device * dev)
6594 {
6595         /* This is what we report to the outside world */
6596
6597         int nFree;
6598         int nDirtyCacheChunks;
6599         int blocksForCheckpoint;
6600
6601 #if 1
6602         nFree = dev->nFreeChunks;
6603 #else
6604         nFree = yaffs_CountFreeChunks(dev);
6605 #endif
6606
6607         nFree += dev->nDeletedFiles;
6608
6609         /* Now count the number of dirty chunks in the cache and subtract those */
6610
6611         {
6612                 int i;
6613                 for (nDirtyCacheChunks = 0, i = 0; i < dev->nShortOpCaches; i++) {
6614                         if (dev->srCache[i].dirty)
6615                                 nDirtyCacheChunks++;
6616                 }
6617         }
6618
6619         nFree -= nDirtyCacheChunks;
6620
6621         nFree -= ((dev->nReservedBlocks + 1) * dev->nChunksPerBlock);
6622
6623         /* Now we figure out how much to reserve for the checkpoint and report that... */
6624         blocksForCheckpoint = dev->nCheckpointReservedBlocks - dev->blocksInCheckpoint;
6625         if(blocksForCheckpoint < 0)
6626                 blocksForCheckpoint = 0;
6627
6628         nFree -= (blocksForCheckpoint * dev->nChunksPerBlock);
6629
6630         if (nFree < 0)
6631                 nFree = 0;
6632
6633         return nFree;
6634
6635 }
6636
6637 static int yaffs_freeVerificationFailures;
6638
6639 static void yaffs_VerifyFreeChunks(yaffs_Device * dev)
6640 {
6641         int counted = yaffs_CountFreeChunks(dev);
6642
6643         int difference = dev->nFreeChunks - counted;
6644
6645         if (difference) {
6646                 T(YAFFS_TRACE_ALWAYS,
6647                   (TSTR("Freechunks verification failure %d %d %d" TENDSTR),
6648                    dev->nFreeChunks, counted, difference));
6649                 yaffs_freeVerificationFailures++;
6650         }
6651 }
6652
6653 /*---------------------------------------- YAFFS test code ----------------------*/
6654
6655 #define yaffs_CheckStruct(structure,syze, name) \
6656            if(sizeof(structure) != syze) \
6657                { \
6658                  T(YAFFS_TRACE_ALWAYS,(TSTR("%s should be %d but is %d\n" TENDSTR),\
6659                  name,syze,sizeof(structure))); \
6660                  return YAFFS_FAIL; \
6661                 }
6662
6663 static int yaffs_CheckStructures(void)
6664 {
6665 /*      yaffs_CheckStruct(yaffs_Tags,8,"yaffs_Tags") */
6666 /*      yaffs_CheckStruct(yaffs_TagsUnion,8,"yaffs_TagsUnion") */
6667 /*      yaffs_CheckStruct(yaffs_Spare,16,"yaffs_Spare") */
6668 #ifndef CONFIG_YAFFS_TNODE_LIST_DEBUG
6669         yaffs_CheckStruct(yaffs_Tnode, 2 * YAFFS_NTNODES_LEVEL0, "yaffs_Tnode")
6670 #endif
6671             yaffs_CheckStruct(yaffs_ObjectHeader, 512, "yaffs_ObjectHeader")
6672
6673             return YAFFS_OK;
6674 }