yaffs_guts.c

   1 /*
   2  * YAFFS: Yet another FFS. A NAND-flash specific file system.
   3  *
   4  * Copyright (C) 2002 Aleph One Ltd.
   5  *   for Toby Churchill Ltd and Brightstar Engineering
   6  *
   7  * Created by Charles Manning <charles@aleph1.co.uk>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2 as
  11  * published by the Free Software Foundation.
  12  *
  13  */
  14
  15 const char *yaffs_guts_c_version =
  16     "$Id: yaffs_guts.c,v 1.30 2006-03-01 08:14:32 charles Exp $";
  17
  18 #include "yportenv.h"
  19
  20 #include "yaffsinterface.h"
  21 #include "yaffs_guts.h"
  22 #include "yaffs_tagsvalidity.h"
  23
  24 #include "yaffs_tagscompat.h"
  25
  26 #ifdef CONFIG_YAFFS_WINCE
  27 void yfsd_LockYAFFS(BOOL fsLockOnly);
  28 void yfsd_UnlockYAFFS(BOOL fsLockOnly);
  29 #endif
  30
  31 #define YAFFS_PASSIVE_GC_CHUNKS 2
  32
  33 #include "yaffs_ecc.h"
  34
  35 /* NAND access */
  36
  37 static Y_INLINE int yaffs_ReadChunkWithTagsFromNAND(yaffs_Device * dev,
  38                                                     int chunkInNAND,
  39                                                     __u8 * buffer,
  40                                                     yaffs_ExtendedTags * tags);
  41 static Y_INLINE int yaffs_WriteChunkWithTagsToNAND(yaffs_Device * dev,
  42                                                    int chunkInNAND,
  43                                                    const __u8 * data,
  44                                                    yaffs_ExtendedTags * tags);
  45 static Y_INLINE int yaffs_MarkBlockBad(yaffs_Device * dev, int blockNo);
  46 static Y_INLINE int yaffs_QueryInitialBlockState(yaffs_Device * dev,
  47                                                  int blockNo,
  48                                                  yaffs_BlockState * state,
  49                                                  unsigned *sequenceNumber);
  50 /* Robustification (if it ever comes about...) */
  51 static void yaffs_RetireBlock(yaffs_Device * dev, int blockInNAND);
  52 static void yaffs_HandleWriteChunkError(yaffs_Device * dev, int chunkInNAND);
  53 static void yaffs_HandleWriteChunkOk(yaffs_Device * dev, int chunkInNAND,
  54                                      const __u8 * data,
  55                                      const yaffs_ExtendedTags * tags);
  56 static void yaffs_HandleUpdateChunk(yaffs_Device * dev, int chunkInNAND,
  57                                     const yaffs_ExtendedTags * tags);
  58
  59 /* Other local prototypes */
  60 static int yaffs_UnlinkObject( yaffs_Object *obj);
  61
  62 static int yaffs_WriteNewChunkWithTagsToNAND(yaffs_Device * dev,
  63                                              const __u8 * buffer,
  64                                              yaffs_ExtendedTags * tags,
  65                                              int useReserve);
  66 static int yaffs_PutChunkIntoFile(yaffs_Object * in, int chunkInInode,
  67                                   int chunkInNAND, int inScan);
  68
  69 static yaffs_Object *yaffs_CreateNewObject(yaffs_Device * dev, int number,
  70                                            yaffs_ObjectType type);
  71 static void yaffs_AddObjectToDirectory(yaffs_Object * directory,
  72                                        yaffs_Object * obj);
  73 static int yaffs_UpdateObjectHeader(yaffs_Object * in, const YCHAR * name,
  74                                     int force, int isShrink, int shadows);
  75 static void yaffs_RemoveObjectFromDirectory(yaffs_Object * obj);
  76 static int yaffs_CheckStructures(void);
  77 static int yaffs_DeleteWorker(yaffs_Object * in, yaffs_Tnode * tn, __u32 level,
  78                               int chunkOffset, int *limit);
  79 static int yaffs_DoGenericObjectDeletion(yaffs_Object * in);
  80
  81 static yaffs_BlockInfo *yaffs_GetBlockInfo(yaffs_Device * dev, int blockNo);
  82
  83 static __u8 *yaffs_GetTempBuffer(yaffs_Device * dev, int lineNo);
  84 static void yaffs_ReleaseTempBuffer(yaffs_Device * dev, __u8 * buffer,
  85                                     int lineNo);
  86
  87 static int yaffs_CheckChunkErased(struct yaffs_DeviceStruct *dev,
  88                                   int chunkInNAND);
  89
  90 static int yaffs_UnlinkWorker(yaffs_Object * obj);
  91 static void yaffs_DestroyObject(yaffs_Object * obj);
  92
  93 static int yaffs_TagsMatch(const yaffs_ExtendedTags * tags, int objectId,
  94                            int chunkInObject);
  95
  96 loff_t yaffs_GetFileSize(yaffs_Object * obj);
  97
  98 static int yaffs_AllocateChunk(yaffs_Device * dev, int useReserve);
  99
 100 static void yaffs_VerifyFreeChunks(yaffs_Device * dev);
 101
 102 #ifdef YAFFS_PARANOID
 103 static int yaffs_CheckFileSanity(yaffs_Object * in);
 104 #else
 105 #define yaffs_CheckFileSanity(in)
 106 #endif
 107
 108 static void yaffs_InvalidateWholeChunkCache(yaffs_Object * in);
 109 static void yaffs_InvalidateChunkCache(yaffs_Object * object, int chunkId);
 110
 111
 112 /*
 113  *   Start of real code.
 114  */
 115
 116 /*
 117  * NAND access layer
 118  */
 119
 120
 121
 122 static int yaffs_ReadChunkWithTagsFromNAND(yaffs_Device * dev, int chunkInNAND,
 123                                            __u8 * buffer,
 124                                            yaffs_ExtendedTags * tags)
 125 {
 126         chunkInNAND -= dev->chunkOffset;
 127
 128         if (dev->readChunkWithTagsFromNAND)
 129                 return dev->readChunkWithTagsFromNAND(dev, chunkInNAND, buffer,
 130                                                       tags);
 131         else
 132                 return yaffs_TagsCompatabilityReadChunkWithTagsFromNAND(dev,
 133                                                                         chunkInNAND,
 134                                                                         buffer,
 135                                                                         tags);
 136 }
 137
 138 static Y_INLINE int yaffs_WriteChunkWithTagsToNAND(yaffs_Device * dev,
 139                                                    int chunkInNAND,
 140                                                    const __u8 * buffer,
 141                                                    yaffs_ExtendedTags * tags)
 142 {
 143         chunkInNAND -= dev->chunkOffset;
 144
 145         if (tags) {
 146                 tags->sequenceNumber = dev->sequenceNumber;
 147                 tags->chunkUsed = 1;
 148                 if (!yaffs_ValidateTags(tags)) {
 149                         T(YAFFS_TRACE_ERROR,
 150                           (TSTR("Writing uninitialised tags" TENDSTR)));
 151                         YBUG();
 152                 }
 153                 T(YAFFS_TRACE_WRITE,
 154                   (TSTR("Writing chunk %d tags %d %d" TENDSTR), chunkInNAND,
 155                    tags->objectId, tags->chunkId));
 156         } else {
 157                 T(YAFFS_TRACE_ERROR, (TSTR("Writing with no tags" TENDSTR)));
 158                 YBUG();
 159         }
 160
 161         if (dev->writeChunkWithTagsToNAND)
 162                 return dev->writeChunkWithTagsToNAND(dev, chunkInNAND, buffer,
 163                                                      tags);
 164         else
 165                 return yaffs_TagsCompatabilityWriteChunkWithTagsToNAND(dev,
 166                                                                        chunkInNAND,
 167                                                                        buffer,
 168                                                                        tags);
 169 }
 170
 171 static Y_INLINE int yaffs_MarkBlockBad(yaffs_Device * dev, int blockNo)
 172 {
 173         blockNo -= dev->blockOffset;
 174
 175         if (dev->markNANDBlockBad)
 176                 return dev->markNANDBlockBad(dev, blockNo);
 177         else
 178                 return yaffs_TagsCompatabilityMarkNANDBlockBad(dev, blockNo);
 179 }
 180 static Y_INLINE int yaffs_QueryInitialBlockState(yaffs_Device * dev,
 181                                                  int blockNo,
 182                                                  yaffs_BlockState * state,
 183                                                  unsigned *sequenceNumber)
 184 {
 185         blockNo -= dev->blockOffset;
 186
 187         if (dev->queryNANDBlock)
 188                 return dev->queryNANDBlock(dev, blockNo, state, sequenceNumber);
 189         else
 190                 return yaffs_TagsCompatabilityQueryNANDBlock(dev, blockNo,
 191                                                              state,
 192                                                              sequenceNumber);
 193 }
 194
 195 static int yaffs_EraseBlockInNAND(struct yaffs_DeviceStruct *dev,
 196                                   int blockInNAND)
 197 {
 198         int result;
 199
 200         blockInNAND -= dev->blockOffset;
 201
 202         dev->nBlockErasures++;
 203         result = dev->eraseBlockInNAND(dev, blockInNAND);
 204
 205         /* If at first we don't succeed, try again *once*.*/
 206         if (!result)
 207                 result = dev->eraseBlockInNAND(dev, blockInNAND);
 208         return result;
 209 }
 210
 211 static int yaffs_InitialiseNAND(struct yaffs_DeviceStruct *dev)
 212 {
 213         return dev->initialiseNAND(dev);
 214 }
 215
 216 /*
 217  * Temporary buffer manipulations.
 218  */
 219
 220 static __u8 *yaffs_GetTempBuffer(yaffs_Device * dev, int lineNo)
 221 {
 222         int i, j;
 223         for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
 224                 if (dev->tempBuffer[i].line == 0) {
 225                         dev->tempBuffer[i].line = lineNo;
 226                         if ((i + 1) > dev->maxTemp) {
 227                                 dev->maxTemp = i + 1;
 228                                 for (j = 0; j <= i; j++)
 229                                         dev->tempBuffer[j].maxLine =
 230                                             dev->tempBuffer[j].line;
 231                         }
 232
 233                         return dev->tempBuffer[i].buffer;
 234                 }
 235         }
 236
 237         T(YAFFS_TRACE_BUFFERS,
 238           (TSTR("Out of temp buffers at line %d, other held by lines:"),
 239            lineNo));
 240         for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
 241                 T(YAFFS_TRACE_BUFFERS, (TSTR(" %d "), dev->tempBuffer[i].line));
 242         }
 243         T(YAFFS_TRACE_BUFFERS, (TSTR(" " TENDSTR)));
 244
 245         /*
 246          * If we got here then we have to allocate an unmanaged one
 247          * This is not good.
 248          */
 249
 250         dev->unmanagedTempAllocations++;
 251         return YMALLOC(dev->nBytesPerChunk);
 252
 253 }
 254
 255 static void yaffs_ReleaseTempBuffer(yaffs_Device * dev, __u8 * buffer,
 256                                     int lineNo)
 257 {
 258         int i;
 259         for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
 260                 if (dev->tempBuffer[i].buffer == buffer) {
 261                         dev->tempBuffer[i].line = 0;
 262                         return;
 263                 }
 264         }
 265
 266         if (buffer) {
 267                 /* assume it is an unmanaged one. */
 268                 T(YAFFS_TRACE_BUFFERS,
 269                   (TSTR("Releasing unmanaged temp buffer in line %d" TENDSTR),
 270                    lineNo));
 271                 YFREE(buffer);
 272                 dev->unmanagedTempDeallocations++;
 273         }
 274
 275 }
 276
 277 /*
 278  * Chunk bitmap manipulations
 279  */
 280
 281 static Y_INLINE __u8 *yaffs_BlockBits(yaffs_Device * dev, int blk)
 282 {
 283         if (blk < dev->internalStartBlock || blk > dev->internalEndBlock) {
 284                 T(YAFFS_TRACE_ERROR,
 285                   (TSTR("**>> yaffs: BlockBits block %d is not valid" TENDSTR),
 286                    blk));
 287                 YBUG();
 288         }
 289         return dev->chunkBits +
 290             (dev->chunkBitmapStride * (blk - dev->internalStartBlock));
 291 }
 292
 293 static Y_INLINE void yaffs_ClearChunkBits(yaffs_Device * dev, int blk)
 294 {
 295         __u8 *blkBits = yaffs_BlockBits(dev, blk);
 296
 297         memset(blkBits, 0, dev->chunkBitmapStride);
 298 }
 299
 300 static Y_INLINE void yaffs_ClearChunkBit(yaffs_Device * dev, int blk, int chunk)
 301 {
 302         __u8 *blkBits = yaffs_BlockBits(dev, blk);
 303
 304         blkBits[chunk / 8] &= ~(1 << (chunk & 7));
 305 }
 306
 307 static Y_INLINE void yaffs_SetChunkBit(yaffs_Device * dev, int blk, int chunk)
 308 {
 309         __u8 *blkBits = yaffs_BlockBits(dev, blk);
 310
 311         blkBits[chunk / 8] |= (1 << (chunk & 7));
 312 }
 313
 314 static Y_INLINE int yaffs_CheckChunkBit(yaffs_Device * dev, int blk, int chunk)
 315 {
 316         __u8 *blkBits = yaffs_BlockBits(dev, blk);
 317         return (blkBits[chunk / 8] & (1 << (chunk & 7))) ? 1 : 0;
 318 }
 319
 320 static Y_INLINE int yaffs_StillSomeChunkBits(yaffs_Device * dev, int blk)
 321 {
 322         __u8 *blkBits = yaffs_BlockBits(dev, blk);
 323         int i;
 324         for (i = 0; i < dev->chunkBitmapStride; i++) {
 325                 if (*blkBits)
 326                         return 1;
 327                 blkBits++;
 328         }
 329         return 0;
 330 }
 331
 332 /*
 333  *  Simple hash function. Needs to have a reasonable spread
 334  */
 335
 336 static Y_INLINE int yaffs_HashFunction(int n)
 337 {
 338         n = abs(n);
 339         return (n % YAFFS_NOBJECT_BUCKETS);
 340 }
 341
 342 /*
 343  * Access functions to useful fake objects
 344  */
 345
 346 yaffs_Object *yaffs_Root(yaffs_Device * dev)
 347 {
 348         return dev->rootDir;
 349 }
 350
 351 yaffs_Object *yaffs_LostNFound(yaffs_Device * dev)
 352 {
 353         return dev->lostNFoundDir;
 354 }
 355
 356
 357 /*
 358  *  Erased NAND checking functions
 359  */
 360
 361 int yaffs_CheckFF(__u8 * buffer, int nBytes)
 362 {
 363         /* Horrible, slow implementation */
 364         while (nBytes--) {
 365                 if (*buffer != 0xFF)
 366                         return 0;
 367                 buffer++;
 368         }
 369         return 1;
 370 }
 371
 372 static int yaffs_CheckChunkErased(struct yaffs_DeviceStruct *dev,
 373                                   int chunkInNAND)
 374 {
 375
 376         int retval = YAFFS_OK;
 377         __u8 *data = yaffs_GetTempBuffer(dev, __LINE__);
 378         yaffs_ExtendedTags tags;
 379
 380         yaffs_ReadChunkWithTagsFromNAND(dev, chunkInNAND, data, &tags);
 381
 382         if (!yaffs_CheckFF(data, dev->nBytesPerChunk) || tags.chunkUsed) {
 383                 T(YAFFS_TRACE_NANDACCESS,
 384                   (TSTR("Chunk %d not erased" TENDSTR), chunkInNAND));
 385                 retval = YAFFS_FAIL;
 386         }
 387
 388         yaffs_ReleaseTempBuffer(dev, data, __LINE__);
 389
 390         return retval;
 391
 392 }
 393
 394 static int yaffs_WriteNewChunkWithTagsToNAND(struct yaffs_DeviceStruct *dev,
 395                                              const __u8 * data,
 396                                              yaffs_ExtendedTags * tags,
 397                                              int useReserve)
 398 {
 399         int chunk;
 400
 401         int writeOk = 1;
 402         int attempts = 0;
 403
 404         do {
 405                 chunk = yaffs_AllocateChunk(dev, useReserve);
 406
 407                 if (chunk >= 0) {
 408
 409                         /* First check this chunk is erased... */
 410 #ifndef CONFIG_YAFFS_DISABLE_CHUNK_ERASED_CHECK
 411                         writeOk = yaffs_CheckChunkErased(dev, chunk);
 412 #endif
 413                         if (!writeOk) {
 414                                 T(YAFFS_TRACE_ERROR,
 415                                   (TSTR
 416                                    ("**>> yaffs chunk %d was not erased"
 417                                     TENDSTR), chunk));
 418                         } else {
 419                                 writeOk =
 420                                     yaffs_WriteChunkWithTagsToNAND(dev, chunk,
 421                                                                    data, tags);
 422                         }
 423                         attempts++;
 424
 425                         if (writeOk) {
 426                                 /*
 427                                  *  Copy the data into the robustification buffer.
 428                                  *  NB We do this at the end to prevent duplicates in the case of a write error.
 429                                  *  Todo
 430                                  */
 431                                 yaffs_HandleWriteChunkOk(dev, chunk, data,
 432                                                          tags);
 433                         } else {
 434                                 yaffs_HandleWriteChunkError(dev, chunk);
 435                         }
 436                 }
 437
 438         } while (chunk >= 0 && !writeOk);
 439
 440         if (attempts > 1) {
 441                 T(YAFFS_TRACE_ERROR,
 442                   (TSTR("**>> yaffs write required %d attempts" TENDSTR),
 443                    attempts));
 444                 dev->nRetriedWrites += (attempts - 1);
 445         }
 446
 447         return chunk;
 448 }
 449
 450 /*
 451  * Block retiring for handling a broken block.
 452  */
 453
 454 static void yaffs_RetireBlock(yaffs_Device * dev, int blockInNAND)
 455 {
 456
 457         yaffs_MarkBlockBad(dev, blockInNAND);
 458
 459         yaffs_GetBlockInfo(dev, blockInNAND)->blockState =
 460             YAFFS_BLOCK_STATE_DEAD;
 461
 462         dev->nRetiredBlocks++;
 463 }
 464
 465 /*
 466  * Functions for robustisizing TODO
 467  *
 468  */
 469
 470 static void yaffs_HandleWriteChunkOk(yaffs_Device * dev, int chunkInNAND,
 471                                      const __u8 * data,
 472                                      const yaffs_ExtendedTags * tags)
 473 {
 474 }
 475
 476 static void yaffs_HandleUpdateChunk(yaffs_Device * dev, int chunkInNAND,
 477                                     const yaffs_ExtendedTags * tags)
 478 {
 479 }
 480
 481 static void yaffs_HandleWriteChunkError(yaffs_Device * dev, int chunkInNAND)
 482 {
 483         int blockInNAND = chunkInNAND / dev->nChunksPerBlock;
 484
 485         /* Mark the block for retirement */
 486         yaffs_GetBlockInfo(dev, blockInNAND)->needsRetiring = 1;
 487         /* Delete the chunk */
 488         yaffs_DeleteChunk(dev, chunkInNAND, 1, __LINE__);
 489 }
 490
 491
 492 /*---------------- Name handling functions ------------*/
 493
 494 static __u16 yaffs_CalcNameSum(const YCHAR * name)
 495 {
 496         __u16 sum = 0;
 497         __u16 i = 1;
 498
 499         YUCHAR *bname = (YUCHAR *) name;
 500         if (bname) {
 501                 while ((*bname) && (i <= YAFFS_MAX_NAME_LENGTH)) {
 502
 503 #ifdef CONFIG_YAFFS_CASE_INSENSITIVE
 504                         sum += yaffs_toupper(*bname) * i;
 505 #else
 506                         sum += (*bname) * i;
 507 #endif
 508                         i++;
 509                         bname++;
 510                 }
 511         }
 512         return sum;
 513 }
 514
 515 static void yaffs_SetObjectName(yaffs_Object * obj, const YCHAR * name)
 516 {
 517 #ifdef CONFIG_YAFFS_SHORT_NAMES_IN_RAM
 518         if (name && yaffs_strlen(name) <= YAFFS_SHORT_NAME_LENGTH) {
 519                 yaffs_strcpy(obj->shortName, name);
 520         } else {
 521                 obj->shortName[0] = _Y('\0');
 522         }
 523 #endif
 524         obj->sum = yaffs_CalcNameSum(name);
 525 }
 526
 527 /*-------------------- TNODES -------------------
 528
 529  * List of spare tnodes
 530  * The list is hooked together using the first pointer
 531  * in the tnode.
 532  */
 533
 534 /* yaffs_CreateTnodes creates a bunch more tnodes and
 535  * adds them to the tnode free list.
 536  * Don't use this function directly
 537  */
 538
 539 static int yaffs_CreateTnodes(yaffs_Device * dev, int nTnodes)
 540 {
 541         int i;
 542         int tnodeSize;
 543         yaffs_Tnode *newTnodes;
 544         __u8 *mem;
 545         yaffs_Tnode *curr;
 546         yaffs_Tnode *next;
 547         yaffs_TnodeList *tnl;
 548
 549         if (nTnodes < 1)
 550                 return YAFFS_OK;
 551
 552         /* Calculate the tnode size in bytes for variable width tnode support.
 553          * Must be a multiple of 32-bits  */
 554         tnodeSize = (dev->tnodeWidth * YAFFS_NTNODES_LEVEL0)/8;
 555
 556         /* make these things */
 557
 558         newTnodes = YMALLOC(nTnodes * tnodeSize);
 559         mem = (__u8 *)newTnodes;
 560
 561         if (!newTnodes) {
 562                 T(YAFFS_TRACE_ERROR,
 563                   (TSTR("yaffs: Could not allocate Tnodes" TENDSTR)));
 564                 return YAFFS_FAIL;
 565         }
 566
 567         /* Hook them into the free list */
 568 #if 0
 569         for (i = 0; i < nTnodes - 1; i++) {
 570                 newTnodes[i].internal[0] = &newTnodes[i + 1];
 571 #ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
 572                 newTnodes[i].internal[YAFFS_NTNODES_INTERNAL] = (void *)1;
 573 #endif
 574         }
 575
 576         newTnodes[nTnodes - 1].internal[0] = dev->freeTnodes;
 577 #ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
 578         newTnodes[nTnodes - 1].internal[YAFFS_NTNODES_INTERNAL] = (void *)1;
 579 #endif
 580         dev->freeTnodes = newTnodes;
 581 #else
 582         /* New hookup for wide tnodes */
 583         for(i = 0; i < nTnodes -1; i++) {
 584                 curr = (yaffs_Tnode *) &mem[i * tnodeSize];
 585                 next = (yaffs_Tnode *) &mem[(i+1) * tnodeSize];
 586                 curr->internal[0] = next;
 587         }
 588
 589         curr = (yaffs_Tnode *) &mem[(nTnodes - 1) * tnodeSize];
 590         curr->internal[0] = dev->freeTnodes;
 591         dev->freeTnodes = (yaffs_Tnode *)mem;
 592
 593 #endif
 594
 595
 596         dev->nFreeTnodes += nTnodes;
 597         dev->nTnodesCreated += nTnodes;
 598
 599         /* Now add this bunch of tnodes to a list for freeing up.
 600          * NB If we can't add this to the management list it isn't fatal
 601          * but it just means we can't free this bunch of tnodes later.
 602          */
 603
 604         tnl = YMALLOC(sizeof(yaffs_TnodeList));
 605         if (!tnl) {
 606                 T(YAFFS_TRACE_ERROR,
 607                   (TSTR
 608                    ("yaffs: Could not add tnodes to management list" TENDSTR)));
 609
 610         } else {
 611                 tnl->tnodes = newTnodes;
 612                 tnl->next = dev->allocatedTnodeList;
 613                 dev->allocatedTnodeList = tnl;
 614         }
 615
 616         T(YAFFS_TRACE_ALLOCATE, (TSTR("yaffs: Tnodes added" TENDSTR)));
 617
 618         return YAFFS_OK;
 619 }
 620
 621 /* GetTnode gets us a clean tnode. Tries to make allocate more if we run out */
 622
 623 static yaffs_Tnode *yaffs_GetTnode(yaffs_Device * dev)
 624 {
 625         yaffs_Tnode *tn = NULL;
 626
 627         /* If there are none left make more */
 628         if (!dev->freeTnodes) {
 629                 yaffs_CreateTnodes(dev, YAFFS_ALLOCATION_NTNODES);
 630         }
 631
 632         if (dev->freeTnodes) {
 633                 tn = dev->freeTnodes;
 634 #ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
 635                 if (tn->internal[YAFFS_NTNODES_INTERNAL] != (void *)1) {
 636                         /* Hoosterman, this thing looks like it isn't in the list */
 637                         T(YAFFS_TRACE_ALWAYS,
 638                           (TSTR("yaffs: Tnode list bug 1" TENDSTR)));
 639                 }
 640 #endif
 641                 dev->freeTnodes = dev->freeTnodes->internal[0];
 642                 dev->nFreeTnodes--;
 643                 /* zero out */
 644                 memset(tn, 0, (dev->tnodeWidth * YAFFS_NTNODES_LEVEL0)/8);
 645         }
 646
 647         return tn;
 648 }
 649
 650 /* FreeTnode frees up a tnode and puts it back on the free list */
 651 static void yaffs_FreeTnode(yaffs_Device * dev, yaffs_Tnode * tn)
 652 {
 653         if (tn) {
 654 #ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
 655                 if (tn->internal[YAFFS_NTNODES_INTERNAL] != 0) {
 656                         /* Hoosterman, this thing looks like it is already in the list */
 657                         T(YAFFS_TRACE_ALWAYS,
 658                           (TSTR("yaffs: Tnode list bug 2" TENDSTR)));
 659                 }
 660                 tn->internal[YAFFS_NTNODES_INTERNAL] = (void *)1;
 661 #endif
 662                 tn->internal[0] = dev->freeTnodes;
 663                 dev->freeTnodes = tn;
 664                 dev->nFreeTnodes++;
 665         }
 666 }
 667
 668 static void yaffs_DeinitialiseTnodes(yaffs_Device * dev)
 669 {
 670         /* Free the list of allocated tnodes */
 671         yaffs_TnodeList *tmp;
 672
 673         while (dev->allocatedTnodeList) {
 674                 tmp = dev->allocatedTnodeList->next;
 675
 676                 YFREE(dev->allocatedTnodeList->tnodes);
 677                 YFREE(dev->allocatedTnodeList);
 678                 dev->allocatedTnodeList = tmp;
 679
 680         }
 681
 682         dev->freeTnodes = NULL;
 683         dev->nFreeTnodes = 0;
 684 }
 685
 686 static void yaffs_InitialiseTnodes(yaffs_Device * dev)
 687 {
 688         dev->allocatedTnodeList = NULL;
 689         dev->freeTnodes = NULL;
 690         dev->nFreeTnodes = 0;
 691         dev->nTnodesCreated = 0;
 692
 693 }
 694
 695
 696 void yaffs_PutLevel0Tnode(yaffs_Device *dev, yaffs_Tnode *tn, unsigned pos, unsigned val)
 697 {
 698   __u32 *map = (__u32 *)tn;
 699   __u32 bitInMap;
 700   __u32 bitInWord;
 701   __u32 wordInMap;
 702   __u32 mask;
 703
 704   pos &= YAFFS_TNODES_LEVEL0_MASK;
 705   val >>= dev->chunkGroupBits;
 706
 707   bitInMap = pos * dev->tnodeWidth;
 708   wordInMap = bitInMap /32;
 709   bitInWord = bitInMap & (32 -1);
 710
 711   mask = dev->tnodeMask << bitInWord;
 712
 713   map[wordInMap] &= ~mask;
 714   map[wordInMap] |= (mask & (val << bitInWord));
 715
 716   if(dev->tnodeWidth > (32-bitInWord)) {
 717     bitInWord = (32 - bitInWord);
 718     wordInMap++;;
 719     mask = dev->tnodeMask >> (/*dev->tnodeWidth -*/ bitInWord);
 720     map[wordInMap] &= ~mask;
 721     map[wordInMap] |= (mask & (val >> bitInWord));
 722   }
 723 }
 724
 725 __u32 yaffs_GetChunkGroupBase(yaffs_Device *dev, yaffs_Tnode *tn, unsigned pos)
 726 {
 727   __u32 *map = (__u32 *)tn;
 728   __u32 bitInMap;
 729   __u32 bitInWord;
 730   __u32 wordInMap;
 731   __u32 val;
 732
 733   pos &= YAFFS_TNODES_LEVEL0_MASK;
 734
 735   bitInMap = pos * dev->tnodeWidth;
 736   wordInMap = bitInMap /32;
 737   bitInWord = bitInMap & (32 -1);
 738
 739   val = map[wordInMap] >> bitInWord;
 740
 741   if(dev->tnodeWidth > (32-bitInWord)) {
 742     bitInWord = (32 - bitInWord);
 743     wordInMap++;;
 744     val |= (map[wordInMap] << bitInWord);
 745   }
 746
 747   val &= dev->tnodeMask;
 748   val <<= dev->chunkGroupBits;
 749
 750   return val;
 751 }
 752
 753 /* ------------------- End of individual tnode manipulation -----------------*/
 754
 755 /* ---------Functions to manipulate the look-up tree (made up of tnodes) ------
 756  * The look up tree is represented by the top tnode and the number of topLevel
 757  * in the tree. 0 means only the level 0 tnode is in the tree.
 758  */
 759
 760 /* FindLevel0Tnode finds the level 0 tnode, if one exists. */
 761 static yaffs_Tnode *yaffs_FindLevel0Tnode(yaffs_Device * dev,
 762                                           yaffs_FileStructure * fStruct,
 763                                           __u32 chunkId)
 764 {
 765
 766         yaffs_Tnode *tn = fStruct->top;
 767         __u32 i;
 768         int requiredTallness;
 769         int level = fStruct->topLevel;
 770
 771         /* Check sane level and chunk Id */
 772         if (level < 0 || level > YAFFS_TNODES_MAX_LEVEL) {
 773                 return NULL;
 774         }
 775
 776         if (chunkId > YAFFS_MAX_CHUNK_ID) {
 777                 return NULL;
 778         }
 779
 780         /* First check we're tall enough (ie enough topLevel) */
 781
 782         i = chunkId >> YAFFS_TNODES_LEVEL0_BITS;
 783         requiredTallness = 0;
 784         while (i) {
 785                 i >>= YAFFS_TNODES_INTERNAL_BITS;
 786                 requiredTallness++;
 787         }
 788
 789         if (requiredTallness > fStruct->topLevel) {
 790                 /* Not tall enough, so we can't find it, return NULL. */
 791                 return NULL;
 792         }
 793
 794         /* Traverse down to level 0 */
 795         while (level > 0 && tn) {
 796                 tn = tn->
 797                     internal[(chunkId >>
 798                                ( YAFFS_TNODES_LEVEL0_BITS +
 799                                  (level - 1) *
 800                                  YAFFS_TNODES_INTERNAL_BITS)
 801                               ) &
 802                              YAFFS_TNODES_INTERNAL_MASK];
 803                 level--;
 804
 805         }
 806
 807         return tn;
 808 }
 809
 810 /* AddOrFindLevel0Tnode finds the level 0 tnode if it exists, otherwise first expands the tree.
 811  * This happens in two steps:
 812  *  1. If the tree isn't tall enough, then make it taller.
 813  *  2. Scan down the tree towards the level 0 tnode adding tnodes if required.
 814  *
 815  * Used when modifying the tree.
 816  */
 817
 818 static yaffs_Tnode *yaffs_AddOrFindLevel0Tnode(yaffs_Device * dev,
 819                                                yaffs_FileStructure * fStruct,
 820                                                __u32 chunkId)
 821 {
 822
 823         yaffs_Tnode *tn;
 824
 825         int requiredTallness;
 826         int i;
 827         int l;
 828
 829         __u32 x;
 830
 831
 832         /* Check sane level and page Id */
 833         if (fStruct->topLevel < 0 || fStruct->topLevel > YAFFS_TNODES_MAX_LEVEL) {
 834                 return NULL;
 835         }
 836
 837         if (chunkId > YAFFS_MAX_CHUNK_ID) {
 838                 return NULL;
 839         }
 840
 841         /* First check we're tall enough (ie enough topLevel) */
 842
 843         x = chunkId >> YAFFS_TNODES_LEVEL0_BITS;
 844         requiredTallness = 0;
 845         while (x) {
 846                 x >>= YAFFS_TNODES_INTERNAL_BITS;
 847                 requiredTallness++;
 848         }
 849
 850
 851         if (requiredTallness > fStruct->topLevel) {
 852                 /* Not tall enough,gotta make the tree taller */
 853                 for (i = fStruct->topLevel; i < requiredTallness; i++) {
 854
 855                         tn = yaffs_GetTnode(dev);
 856
 857                         if (tn) {
 858                                 tn->internal[0] = fStruct->top;
 859                                 fStruct->top = tn;
 860                         } else {
 861                                 T(YAFFS_TRACE_ERROR,
 862                                   (TSTR("yaffs: no more tnodes" TENDSTR)));
 863                         }
 864                 }
 865
 866                 fStruct->topLevel = requiredTallness;
 867         }
 868
 869         /* Traverse down to level 0, adding anything we need */
 870
 871         l = fStruct->topLevel;
 872         tn = fStruct->top;
 873         while (l > 0 && tn) {
 874                 x = (chunkId >>
 875                      ( YAFFS_TNODES_LEVEL0_BITS +
 876                       (l - 1) * YAFFS_TNODES_INTERNAL_BITS)) &
 877                     YAFFS_TNODES_INTERNAL_MASK;
 878
 879
 880                 if (!tn->internal[x])
 881                         tn->internal[x] = yaffs_GetTnode(dev);
 882
 883                 tn = tn->internal[x];
 884                 l--;
 885
 886         }
 887
 888         return tn;
 889 }
 890
 891 static int yaffs_FindChunkInGroup(yaffs_Device * dev, int theChunk,
 892                                   yaffs_ExtendedTags * tags, int objectId,
 893                                   int chunkInInode)
 894 {
 895         int j;
 896
 897         for (j = 0; theChunk && j < dev->chunkGroupSize; j++) {
 898                 if (yaffs_CheckChunkBit
 899                     (dev, theChunk / dev->nChunksPerBlock,
 900                      theChunk % dev->nChunksPerBlock)) {
 901                         yaffs_ReadChunkWithTagsFromNAND(dev, theChunk, NULL,
 902                                                         tags);
 903                         if (yaffs_TagsMatch(tags, objectId, chunkInInode)) {
 904                                 /* found it; */
 905                                 return theChunk;
 906
 907                         }
 908                 }
 909                 theChunk++;
 910         }
 911         return -1;
 912 }
 913
 914
 915 /* DeleteWorker scans backwards through the tnode tree and deletes all the
 916  * chunks and tnodes in the file
 917  * Returns 1 if the tree was deleted.
 918  * Returns 0 if it stopped early due to hitting the limit and the delete is incomplete.
 919  */
 920
 921 static int yaffs_DeleteWorker(yaffs_Object * in, yaffs_Tnode * tn, __u32 level,
 922                               int chunkOffset, int *limit)
 923 {
 924         int i;
 925         int chunkInInode;
 926         int theChunk;
 927         yaffs_ExtendedTags tags;
 928         int foundChunk;
 929         yaffs_Device *dev = in->myDev;
 930
 931         int allDone = 1;
 932
 933         if (tn) {
 934                 if (level > 0) {
 935
 936                         for (i = YAFFS_NTNODES_INTERNAL - 1; allDone && i >= 0;
 937                              i--) {
 938                                 if (tn->internal[i]) {
 939                                         if (limit && (*limit) < 0) {
 940                                                 allDone = 0;
 941                                         } else {
 942                                                 allDone =
 943                                                     yaffs_DeleteWorker(in,
 944                                                                        tn->
 945                                                                        internal
 946                                                                        [i],
 947                                                                        level -
 948                                                                        1,
 949                                                                        (chunkOffset
 950                                                                         <<
 951                                                                         YAFFS_TNODES_INTERNAL_BITS)
 952                                                                        + i,
 953                                                                        limit);
 954                                         }
 955                                         if (allDone) {
 956                                                 yaffs_FreeTnode(dev,
 957                                                                 tn->
 958                                                                 internal[i]);
 959                                                 tn->internal[i] = NULL;
 960                                         }
 961                                 }
 962
 963                         }
 964                         return (allDone) ? 1 : 0;
 965                 } else if (level == 0) {
 966                         int hitLimit = 0;
 967
 968                         for (i = YAFFS_NTNODES_LEVEL0 - 1; i >= 0 && !hitLimit;
 969                              i--) {
 970                                 theChunk = yaffs_GetChunkGroupBase(dev,tn,i);
 971                                 if (theChunk) {
 972
 973                                         chunkInInode =
 974                                             (chunkOffset <<
 975                                              YAFFS_TNODES_LEVEL0_BITS) + i;
 976
 977                                         foundChunk =
 978                                             yaffs_FindChunkInGroup(dev,
 979                                                                    theChunk,
 980                                                                    &tags,
 981                                                                    in->objectId,
 982                                                                    chunkInInode);
 983
 984                                         if (foundChunk > 0) {
 985                                                 yaffs_DeleteChunk(dev,
 986                                                                   foundChunk, 1,
 987                                                                   __LINE__);
 988                                                 in->nDataChunks--;
 989                                                 if (limit) {
 990                                                         *limit = *limit - 1;
 991                                                         if (*limit <= 0) {
 992                                                                 hitLimit = 1;
 993                                                         }
 994                                                 }
 995
 996                                         }
 997
 998                                         yaffs_PutLevel0Tnode(dev,tn,i,0);
 999                                 }
1000
1001                         }
1002                         return (i < 0) ? 1 : 0;
1003
1004                 }
1005
1006         }
1007
1008         return 1;
1009
1010 }
1011
1012 static void yaffs_SoftDeleteChunk(yaffs_Device * dev, int chunk)
1013 {
1014
1015         yaffs_BlockInfo *theBlock;
1016
1017         T(YAFFS_TRACE_DELETION, (TSTR("soft delete chunk %d" TENDSTR), chunk));
1018
1019         theBlock = yaffs_GetBlockInfo(dev, chunk / dev->nChunksPerBlock);
1020         if (theBlock) {
1021                 theBlock->softDeletions++;
1022                 dev->nFreeChunks++;
1023         }
1024 }
1025
1026 /* SoftDeleteWorker scans backwards through the tnode tree and soft deletes all the chunks in the file.
1027  * All soft deleting does is increment the block's softdelete count and pulls the chunk out
1028  * of the tnode.
1029  * Thus, essentially this is the same as DeleteWorker except that the chunks are soft deleted.
1030  */
1031
1032 static int yaffs_SoftDeleteWorker(yaffs_Object * in, yaffs_Tnode * tn,
1033                                   __u32 level, int chunkOffset)
1034 {
1035         int i;
1036         int theChunk;
1037         int allDone = 1;
1038         yaffs_Device *dev = in->myDev;
1039
1040         if (tn) {
1041                 if (level > 0) {
1042
1043                         for (i = YAFFS_NTNODES_INTERNAL - 1; allDone && i >= 0;
1044                              i--) {
1045                                 if (tn->internal[i]) {
1046                                         allDone =
1047                                             yaffs_SoftDeleteWorker(in,
1048                                                                    tn->
1049                                                                    internal[i],
1050                                                                    level - 1,
1051                                                                    (chunkOffset
1052                                                                     <<
1053                                                                     YAFFS_TNODES_INTERNAL_BITS)
1054                                                                    + i);
1055                                         if (allDone) {
1056                                                 yaffs_FreeTnode(dev,
1057                                                                 tn->
1058                                                                 internal[i]);
1059                                                 tn->internal[i] = NULL;
1060                                         } else {
1061                                                 /* Hoosterman... how could this happen? */
1062                                         }
1063                                 }
1064                         }
1065                         return (allDone) ? 1 : 0;
1066                 } else if (level == 0) {
1067
1068                         for (i = YAFFS_NTNODES_LEVEL0 - 1; i >= 0; i--) {
1069                                 theChunk = yaffs_GetChunkGroupBase(dev,tn,i);
1070                                 if (theChunk) {
1071                                         /* Note this does not find the real chunk, only the chunk group.
1072                                          * We make an assumption that a chunk group is not larger than
1073                                          * a block.
1074                                          */
1075                                         yaffs_SoftDeleteChunk(dev, theChunk);
1076                                         yaffs_PutLevel0Tnode(dev,tn,i,0);
1077                                 }
1078
1079                         }
1080                         return 1;
1081
1082                 }
1083
1084         }
1085
1086         return 1;
1087
1088 }
1089
1090 static void yaffs_SoftDeleteFile(yaffs_Object * obj)
1091 {
1092         if (obj->deleted &&
1093             obj->variantType == YAFFS_OBJECT_TYPE_FILE && !obj->softDeleted) {
1094                 if (obj->nDataChunks <= 0) {
1095                         /* Empty file with no duplicate object headers, just delete it immediately */
1096                         yaffs_FreeTnode(obj->myDev,
1097                                         obj->variant.fileVariant.top);
1098                         obj->variant.fileVariant.top = NULL;
1099                         T(YAFFS_TRACE_TRACING,
1100                           (TSTR("yaffs: Deleting empty file %d" TENDSTR),
1101                            obj->objectId));
1102                         yaffs_DoGenericObjectDeletion(obj);
1103                 } else {
1104                         yaffs_SoftDeleteWorker(obj,
1105                                                obj->variant.fileVariant.top,
1106                                                obj->variant.fileVariant.
1107                                                topLevel, 0);
1108                         obj->softDeleted = 1;
1109                 }
1110         }
1111 }
1112
1113 /* Pruning removes any part of the file structure tree that is beyond the
1114  * bounds of the file (ie that does not point to chunks).
1115  *
1116  * A file should only get pruned when its size is reduced.
1117  *
1118  * Before pruning, the chunks must be pulled from the tree and the
1119  * level 0 tnode entries must be zeroed out.
1120  * Could also use this for file deletion, but that's probably better handled
1121  * by a special case.
1122  */
1123
1124 static yaffs_Tnode *yaffs_PruneWorker(yaffs_Device * dev, yaffs_Tnode * tn,
1125                                       __u32 level, int del0)
1126 {
1127         int i;
1128         int hasData;
1129
1130         if (tn) {
1131                 hasData = 0;
1132
1133                 for (i = 0; i < YAFFS_NTNODES_INTERNAL; i++) {
1134                         if (tn->internal[i] && level > 0) {
1135                                 tn->internal[i] =
1136                                     yaffs_PruneWorker(dev, tn->internal[i],
1137                                                       level - 1,
1138                                                       (i == 0) ? del0 : 1);
1139                         }
1140
1141                         if (tn->internal[i]) {
1142                                 hasData++;
1143                         }
1144                 }
1145
1146                 if (hasData == 0 && del0) {
1147                         /* Free and return NULL */
1148
1149                         yaffs_FreeTnode(dev, tn);
1150                         tn = NULL;
1151                 }
1152
1153         }
1154
1155         return tn;
1156
1157 }
1158
1159 static int yaffs_PruneFileStructure(yaffs_Device * dev,
1160                                     yaffs_FileStructure * fStruct)
1161 {
1162         int i;
1163         int hasData;
1164         int done = 0;
1165         yaffs_Tnode *tn;
1166
1167         if (fStruct->topLevel > 0) {
1168                 fStruct->top =
1169                     yaffs_PruneWorker(dev, fStruct->top, fStruct->topLevel, 0);
1170
1171                 /* Now we have a tree with all the non-zero branches NULL but the height
1172                  * is the same as it was.
1173                  * Let's see if we can trim internal tnodes to shorten the tree.
1174                  * We can do this if only the 0th element in the tnode is in use
1175                  * (ie all the non-zero are NULL)
1176                  */
1177
1178                 while (fStruct->topLevel && !done) {
1179                         tn = fStruct->top;
1180
1181                         hasData = 0;
1182                         for (i = 1; i < YAFFS_NTNODES_INTERNAL; i++) {
1183                                 if (tn->internal[i]) {
1184                                         hasData++;
1185                                 }
1186                         }
1187
1188                         if (!hasData) {
1189                                 fStruct->top = tn->internal[0];
1190                                 fStruct->topLevel--;
1191                                 yaffs_FreeTnode(dev, tn);
1192                         } else {
1193                                 done = 1;
1194                         }
1195                 }
1196         }
1197
1198         return YAFFS_OK;
1199 }
1200
1201 /*-------------------- End of File Structure functions.-------------------*/
1202
1203 /* yaffs_CreateFreeObjects creates a bunch more objects and
1204  * adds them to the object free list.
1205  */
1206 static int yaffs_CreateFreeObjects(yaffs_Device * dev, int nObjects)
1207 {
1208         int i;
1209         yaffs_Object *newObjects;
1210         yaffs_ObjectList *list;
1211
1212         if (nObjects < 1)
1213                 return YAFFS_OK;
1214
1215         /* make these things */
1216         newObjects = YMALLOC(nObjects * sizeof(yaffs_Object));
1217
1218         if (!newObjects) {
1219                 T(YAFFS_TRACE_ALLOCATE,
1220                   (TSTR("yaffs: Could not allocate more objects" TENDSTR)));
1221                 return YAFFS_FAIL;
1222         }
1223
1224         /* Hook them into the free list */
1225         for (i = 0; i < nObjects - 1; i++) {
1226                 newObjects[i].siblings.next =
1227                     (struct list_head *)(&newObjects[i + 1]);
1228         }
1229
1230         newObjects[nObjects - 1].siblings.next = (void *)dev->freeObjects;
1231         dev->freeObjects = newObjects;
1232         dev->nFreeObjects += nObjects;
1233         dev->nObjectsCreated += nObjects;
1234
1235         /* Now add this bunch of Objects to a list for freeing up. */
1236
1237         list = YMALLOC(sizeof(yaffs_ObjectList));
1238         if (!list) {
1239                 T(YAFFS_TRACE_ALLOCATE,
1240                   (TSTR("Could not add objects to management list" TENDSTR)));
1241         } else {
1242                 list->objects = newObjects;
1243                 list->next = dev->allocatedObjectList;
1244                 dev->allocatedObjectList = list;
1245         }
1246
1247         return YAFFS_OK;
1248 }
1249
1250
1251 /* AllocateEmptyObject gets us a clean Object. Tries to make allocate more if we run out */
1252 static yaffs_Object *yaffs_AllocateEmptyObject(yaffs_Device * dev)
1253 {
1254         yaffs_Object *tn = NULL;
1255
1256         /* If there are none left make more */
1257         if (!dev->freeObjects) {
1258                 yaffs_CreateFreeObjects(dev, YAFFS_ALLOCATION_NOBJECTS);
1259         }
1260
1261         if (dev->freeObjects) {
1262                 tn = dev->freeObjects;
1263                 dev->freeObjects =
1264                     (yaffs_Object *) (dev->freeObjects->siblings.next);
1265                 dev->nFreeObjects--;
1266
1267                 /* Now sweeten it up... */
1268
1269                 memset(tn, 0, sizeof(yaffs_Object));
1270                 tn->myDev = dev;
1271                 tn->chunkId = -1;
1272                 tn->variantType = YAFFS_OBJECT_TYPE_UNKNOWN;
1273                 INIT_LIST_HEAD(&(tn->hardLinks));
1274                 INIT_LIST_HEAD(&(tn->hashLink));
1275                 INIT_LIST_HEAD(&tn->siblings);
1276
1277                 /* Add it to the lost and found directory.
1278                  * NB Can't put root or lostNFound in lostNFound so
1279                  * check if lostNFound exists first
1280                  */
1281                 if (dev->lostNFoundDir) {
1282                         yaffs_AddObjectToDirectory(dev->lostNFoundDir, tn);
1283                 }
1284         }
1285
1286         return tn;
1287 }
1288
1289 static yaffs_Object *yaffs_CreateFakeDirectory(yaffs_Device * dev, int number,
1290                                                __u32 mode)
1291 {
1292
1293         yaffs_Object *obj =
1294             yaffs_CreateNewObject(dev, number, YAFFS_OBJECT_TYPE_DIRECTORY);
1295         if (obj) {
1296                 obj->fake = 1;          /* it is fake so it has no NAND presence... */
1297                 obj->renameAllowed = 0; /* ... and we're not allowed to rename it... */
1298                 obj->unlinkAllowed = 0; /* ... or unlink it */
1299                 obj->deleted = 0;
1300                 obj->unlinked = 0;
1301                 obj->yst_mode = mode;
1302                 obj->myDev = dev;
1303                 obj->chunkId = 0;       /* Not a valid chunk. */
1304         }
1305
1306         return obj;
1307
1308 }
1309
1310 static void yaffs_UnhashObject(yaffs_Object * tn)
1311 {
1312         int bucket;
1313         yaffs_Device *dev = tn->myDev;
1314
1315         /* If it is still linked into the bucket list, free from the list */
1316         if (!list_empty(&tn->hashLink)) {
1317                 list_del_init(&tn->hashLink);
1318                 bucket = yaffs_HashFunction(tn->objectId);
1319                 dev->objectBucket[bucket].count--;
1320         }
1321
1322 }
1323
1324 /*  FreeObject frees up a Object and puts it back on the free list */
1325 static void yaffs_FreeObject(yaffs_Object * tn)
1326 {
1327
1328         yaffs_Device *dev = tn->myDev;
1329
1330 #ifdef  __KERNEL__
1331         if (tn->myInode) {
1332                 /* We're still hooked up to a cached inode.
1333                  * Don't delete now, but mark for later deletion
1334                  */
1335                 tn->deferedFree = 1;
1336                 return;
1337         }
1338 #endif
1339
1340         yaffs_UnhashObject(tn);
1341
1342         /* Link into the free list. */
1343         tn->siblings.next = (struct list_head *)(dev->freeObjects);
1344         dev->freeObjects = tn;
1345         dev->nFreeObjects++;
1346 }
1347
1348 #ifdef __KERNEL__
1349
1350 void yaffs_HandleDeferedFree(yaffs_Object * obj)
1351 {
1352         if (obj->deferedFree) {
1353                 yaffs_FreeObject(obj);
1354         }
1355 }
1356
1357 #endif
1358
1359 static void yaffs_DeinitialiseObjects(yaffs_Device * dev)
1360 {
1361         /* Free the list of allocated Objects */
1362
1363         yaffs_ObjectList *tmp;
1364
1365         while (dev->allocatedObjectList) {
1366                 tmp = dev->allocatedObjectList->next;
1367                 YFREE(dev->allocatedObjectList->objects);
1368                 YFREE(dev->allocatedObjectList);
1369
1370                 dev->allocatedObjectList = tmp;
1371         }
1372
1373         dev->freeObjects = NULL;
1374         dev->nFreeObjects = 0;
1375 }
1376
1377 static void yaffs_InitialiseObjects(yaffs_Device * dev)
1378 {
1379         int i;
1380
1381         dev->allocatedObjectList = NULL;
1382         dev->freeObjects = NULL;
1383         dev->nFreeObjects = 0;
1384
1385         for (i = 0; i < YAFFS_NOBJECT_BUCKETS; i++) {
1386                 INIT_LIST_HEAD(&dev->objectBucket[i].list);
1387                 dev->objectBucket[i].count = 0;
1388         }
1389
1390 }
1391
1392 static int yaffs_FindNiceObjectBucket(yaffs_Device * dev)
1393 {
1394         static int x = 0;
1395         int i;
1396         int l = 999;
1397         int lowest = 999999;
1398
1399         /* First let's see if we can find one that's empty. */
1400
1401         for (i = 0; i < 10 && lowest > 0; i++) {
1402                 x++;
1403                 x %= YAFFS_NOBJECT_BUCKETS;
1404                 if (dev->objectBucket[x].count < lowest) {
1405                         lowest = dev->objectBucket[x].count;
1406                         l = x;
1407                 }
1408
1409         }
1410
1411         /* If we didn't find an empty list, then try
1412          * looking a bit further for a short one
1413          */
1414
1415         for (i = 0; i < 10 && lowest > 3; i++) {
1416                 x++;
1417                 x %= YAFFS_NOBJECT_BUCKETS;
1418                 if (dev->objectBucket[x].count < lowest) {
1419                         lowest = dev->objectBucket[x].count;
1420                         l = x;
1421                 }
1422
1423         }
1424
1425         return l;
1426 }
1427
1428 static int yaffs_CreateNewObjectNumber(yaffs_Device * dev)
1429 {
1430         int bucket = yaffs_FindNiceObjectBucket(dev);
1431
1432         /* Now find an object value that has not already been taken
1433          * by scanning the list.
1434          */
1435
1436         int found = 0;
1437         struct list_head *i;
1438
1439         __u32 n = (__u32) bucket;
1440
1441         /* yaffs_CheckObjectHashSanity();  */
1442
1443         while (!found) {
1444                 found = 1;
1445                 n += YAFFS_NOBJECT_BUCKETS;
1446                 if (1 || dev->objectBucket[bucket].count > 0) {
1447                         list_for_each(i, &dev->objectBucket[bucket].list) {
1448                                 /* If there is already one in the list */
1449                                 if (i
1450                                     && list_entry(i, yaffs_Object,
1451                                                   hashLink)->objectId == n) {
1452                                         found = 0;
1453                                 }
1454                         }
1455                 }
1456         }
1457
1458
1459         return n;
1460 }
1461
1462 static void yaffs_HashObject(yaffs_Object * in)
1463 {
1464         int bucket = yaffs_HashFunction(in->objectId);
1465         yaffs_Device *dev = in->myDev;
1466
1467         list_add(&in->hashLink, &dev->objectBucket[bucket].list);
1468         dev->objectBucket[bucket].count++;
1469
1470 }
1471
1472 yaffs_Object *yaffs_FindObjectByNumber(yaffs_Device * dev, __u32 number)
1473 {
1474         int bucket = yaffs_HashFunction(number);
1475         struct list_head *i;
1476         yaffs_Object *in;
1477
1478         list_for_each(i, &dev->objectBucket[bucket].list) {
1479                 /* Look if it is in the list */
1480                 if (i) {
1481                         in = list_entry(i, yaffs_Object, hashLink);
1482                         if (in->objectId == number) {
1483 #ifdef __KERNEL__
1484                                 /* Don't tell the VFS about this one if it is defered free */
1485                                 if (in->deferedFree)
1486                                         return NULL;
1487 #endif
1488
1489                                 return in;
1490                         }
1491                 }
1492         }
1493
1494         return NULL;
1495 }
1496
1497 yaffs_Object *yaffs_CreateNewObject(yaffs_Device * dev, int number,
1498                                     yaffs_ObjectType type)
1499 {
1500
1501         yaffs_Object *theObject;
1502
1503         if (number < 0) {
1504                 number = yaffs_CreateNewObjectNumber(dev);
1505         }
1506
1507         theObject = yaffs_AllocateEmptyObject(dev);
1508
1509         if (theObject) {
1510                 theObject->fake = 0;
1511                 theObject->renameAllowed = 1;
1512                 theObject->unlinkAllowed = 1;
1513                 theObject->objectId = number;
1514                 yaffs_HashObject(theObject);
1515                 theObject->variantType = type;
1516 #ifdef CONFIG_YAFFS_WINCE
1517                 yfsd_WinFileTimeNow(theObject->win_atime);
1518                 theObject->win_ctime[0] = theObject->win_mtime[0] =
1519                     theObject->win_atime[0];
1520                 theObject->win_ctime[1] = theObject->win_mtime[1] =
1521                     theObject->win_atime[1];
1522
1523 #else
1524
1525                 theObject->yst_atime = theObject->yst_mtime =
1526                     theObject->yst_ctime = Y_CURRENT_TIME;
1527 #endif
1528                 switch (type) {
1529                 case YAFFS_OBJECT_TYPE_FILE:
1530                         theObject->variant.fileVariant.fileSize = 0;
1531                         theObject->variant.fileVariant.scannedFileSize = 0;
1532                         theObject->variant.fileVariant.shrinkSize = 0xFFFFFFFF; /* max __u32 */
1533                         theObject->variant.fileVariant.topLevel = 0;
1534                         theObject->variant.fileVariant.top =
1535                             yaffs_GetTnode(dev);
1536                         break;
1537                 case YAFFS_OBJECT_TYPE_DIRECTORY:
1538                         INIT_LIST_HEAD(&theObject->variant.directoryVariant.
1539                                        children);
1540                         break;
1541                 case YAFFS_OBJECT_TYPE_SYMLINK:
1542                 case YAFFS_OBJECT_TYPE_HARDLINK:
1543                 case YAFFS_OBJECT_TYPE_SPECIAL:
1544                         /* No action required */
1545                         break;
1546                 case YAFFS_OBJECT_TYPE_UNKNOWN:
1547                         /* todo this should not happen */
1548                         break;
1549                 }
1550         }
1551
1552         return theObject;
1553 }
1554
1555 static yaffs_Object *yaffs_FindOrCreateObjectByNumber(yaffs_Device * dev,
1556                                                       int number,
1557                                                       yaffs_ObjectType type)
1558 {
1559         yaffs_Object *theObject = NULL;
1560
1561         if (number > 0) {
1562                 theObject = yaffs_FindObjectByNumber(dev, number);
1563         }
1564
1565         if (!theObject) {
1566                 theObject = yaffs_CreateNewObject(dev, number, type);
1567         }
1568
1569         return theObject;
1570
1571 }
1572
1573 static YCHAR *yaffs_CloneString(const YCHAR * str)
1574 {
1575         YCHAR *newStr = NULL;
1576
1577         if (str && *str) {
1578                 newStr = YMALLOC((yaffs_strlen(str) + 1) * sizeof(YCHAR));
1579                 yaffs_strcpy(newStr, str);
1580         }
1581
1582         return newStr;
1583
1584 }
1585
1586 /*
1587  * Mknod (create) a new object.
1588  * equivalentObject only has meaning for a hard link;
1589  * aliasString only has meaning for a sumlink.
1590  * rdev only has meaning for devices (a subset of special objects)
1591  */
1592
1593 static yaffs_Object *yaffs_MknodObject(yaffs_ObjectType type,
1594                                        yaffs_Object * parent,
1595                                        const YCHAR * name,
1596                                        __u32 mode,
1597                                        __u32 uid,
1598                                        __u32 gid,
1599                                        yaffs_Object * equivalentObject,
1600                                        const YCHAR * aliasString, __u32 rdev)
1601 {
1602         yaffs_Object *in;
1603
1604         yaffs_Device *dev = parent->myDev;
1605
1606         /* Check if the entry exists. If it does then fail the call since we don't want a dup.*/
1607         if (yaffs_FindObjectByName(parent, name)) {
1608                 return NULL;
1609         }
1610
1611         in = yaffs_CreateNewObject(dev, -1, type);
1612
1613         if (in) {
1614                 in->chunkId = -1;
1615                 in->valid = 1;
1616                 in->variantType = type;
1617
1618                 in->yst_mode = mode;
1619
1620 #ifdef CONFIG_YAFFS_WINCE
1621                 yfsd_WinFileTimeNow(in->win_atime);
1622                 in->win_ctime[0] = in->win_mtime[0] = in->win_atime[0];
1623                 in->win_ctime[1] = in->win_mtime[1] = in->win_atime[1];
1624
1625 #else
1626                 in->yst_atime = in->yst_mtime = in->yst_ctime = Y_CURRENT_TIME;
1627
1628                 in->yst_rdev = rdev;
1629                 in->yst_uid = uid;
1630                 in->yst_gid = gid;
1631 #endif
1632                 in->nDataChunks = 0;
1633
1634                 yaffs_SetObjectName(in, name);
1635                 in->dirty = 1;
1636
1637                 yaffs_AddObjectToDirectory(parent, in);
1638
1639                 in->myDev = parent->myDev;
1640
1641                 switch (type) {
1642                 case YAFFS_OBJECT_TYPE_SYMLINK:
1643                         in->variant.symLinkVariant.alias =
1644                             yaffs_CloneString(aliasString);
1645                         break;
1646                 case YAFFS_OBJECT_TYPE_HARDLINK:
1647                         in->variant.hardLinkVariant.equivalentObject =
1648                             equivalentObject;
1649                         in->variant.hardLinkVariant.equivalentObjectId =
1650                             equivalentObject->objectId;
1651                         list_add(&in->hardLinks, &equivalentObject->hardLinks);
1652                         break;
1653                 case YAFFS_OBJECT_TYPE_FILE:
1654                 case YAFFS_OBJECT_TYPE_DIRECTORY:
1655                 case YAFFS_OBJECT_TYPE_SPECIAL:
1656                 case YAFFS_OBJECT_TYPE_UNKNOWN:
1657                         /* do nothing */
1658                         break;
1659                 }
1660
1661                 if (yaffs_UpdateObjectHeader(in, name, 0, 0, 0) < 0) {
1662                         /* Could not create the object header, fail the creation */
1663                         yaffs_DestroyObject(in);
1664                         in = NULL;
1665                 }
1666
1667         }
1668
1669         return in;
1670 }
1671
1672 yaffs_Object *yaffs_MknodFile(yaffs_Object * parent, const YCHAR * name,
1673                               __u32 mode, __u32 uid, __u32 gid)
1674 {
1675         return yaffs_MknodObject(YAFFS_OBJECT_TYPE_FILE, parent, name, mode,
1676                                  uid, gid, NULL, NULL, 0);
1677 }
1678
1679 yaffs_Object *yaffs_MknodDirectory(yaffs_Object * parent, const YCHAR * name,
1680                                    __u32 mode, __u32 uid, __u32 gid)
1681 {
1682         return yaffs_MknodObject(YAFFS_OBJECT_TYPE_DIRECTORY, parent, name,
1683                                  mode, uid, gid, NULL, NULL, 0);
1684 }
1685
1686 yaffs_Object *yaffs_MknodSpecial(yaffs_Object * parent, const YCHAR * name,
1687                                  __u32 mode, __u32 uid, __u32 gid, __u32 rdev)
1688 {
1689         return yaffs_MknodObject(YAFFS_OBJECT_TYPE_SPECIAL, parent, name, mode,
1690                                  uid, gid, NULL, NULL, rdev);
1691 }
1692
1693 yaffs_Object *yaffs_MknodSymLink(yaffs_Object * parent, const YCHAR * name,
1694                                  __u32 mode, __u32 uid, __u32 gid,
1695                                  const YCHAR * alias)
1696 {
1697         return yaffs_MknodObject(YAFFS_OBJECT_TYPE_SYMLINK, parent, name, mode,
1698                                  uid, gid, NULL, alias, 0);
1699 }
1700
1701 /* yaffs_Link returns the object id of the equivalent object.*/
1702 yaffs_Object *yaffs_Link(yaffs_Object * parent, const YCHAR * name,
1703                          yaffs_Object * equivalentObject)
1704 {
1705         /* Get the real object in case we were fed a hard link as an equivalent object */
1706         equivalentObject = yaffs_GetEquivalentObject(equivalentObject);
1707
1708         if (yaffs_MknodObject
1709             (YAFFS_OBJECT_TYPE_HARDLINK, parent, name, 0, 0, 0,
1710              equivalentObject, NULL, 0)) {
1711                 return equivalentObject;
1712         } else {
1713                 return NULL;
1714         }
1715
1716 }
1717
1718 static int yaffs_ChangeObjectName(yaffs_Object * obj, yaffs_Object * newDir,
1719                                   const YCHAR * newName, int force, int shadows)
1720 {
1721         int unlinkOp;
1722         int deleteOp;
1723
1724         yaffs_Object *existingTarget;
1725
1726         if (newDir == NULL) {
1727                 newDir = obj->parent;   /* use the old directory */
1728         }
1729
1730         if (newDir->variantType != YAFFS_OBJECT_TYPE_DIRECTORY) {
1731                 T(YAFFS_TRACE_ALWAYS,
1732                   (TSTR
1733                    ("tragendy: yaffs_ChangeObjectName: newDir is not a directory"
1734                     TENDSTR)));
1735                 YBUG();
1736         }
1737
1738         /* TODO: Do we need this different handling for YAFFS2 and YAFFS1?? */
1739         if (obj->myDev->isYaffs2) {
1740                 unlinkOp = (newDir == obj->myDev->unlinkedDir);
1741         } else {
1742                 unlinkOp = (newDir == obj->myDev->unlinkedDir
1743                             && obj->variantType == YAFFS_OBJECT_TYPE_FILE);
1744         }
1745
1746         deleteOp = (newDir == obj->myDev->deletedDir);
1747
1748         existingTarget = yaffs_FindObjectByName(newDir, newName);
1749
1750         /* If the object is a file going into the unlinked directory,
1751          *   then it is OK to just stuff it in since duplicate names are allowed.
1752          *   else only proceed if the new name does not exist and if we're putting
1753          *   it into a directory.
1754          */
1755         if ((unlinkOp ||
1756              deleteOp ||
1757              force ||
1758              (shadows > 0) ||
1759              !existingTarget) &&
1760             newDir->variantType == YAFFS_OBJECT_TYPE_DIRECTORY) {
1761                 yaffs_SetObjectName(obj, newName);
1762                 obj->dirty = 1;
1763
1764                 yaffs_AddObjectToDirectory(newDir, obj);
1765
1766                 if (unlinkOp)
1767                         obj->unlinked = 1;
1768
1769                 /* If it is a deletion then we mark it as a shrink for gc purposes. */
1770                 if (yaffs_UpdateObjectHeader(obj, newName, 0, deleteOp, shadows)>= 0)
1771                         return YAFFS_OK;
1772         }
1773
1774         return YAFFS_FAIL;
1775 }
1776
1777 int yaffs_RenameObject(yaffs_Object * oldDir, const YCHAR * oldName,
1778                        yaffs_Object * newDir, const YCHAR * newName)
1779 {
1780         yaffs_Object *obj;
1781         yaffs_Object *existingTarget;
1782         int force = 0;
1783
1784 #ifdef CONFIG_YAFFS_CASE_INSENSITIVE
1785         /* Special case for case insemsitive systems (eg. WinCE).
1786          * While look-up is case insensitive, the name isn't.
1787          * Therefore we might want to change x.txt to X.txt
1788         */
1789         if (oldDir == newDir && yaffs_strcmp(oldName, newName) == 0) {
1790                 force = 1;
1791         }
1792 #endif
1793
1794         obj = yaffs_FindObjectByName(oldDir, oldName);
1795
1796         if (obj && obj->renameAllowed) {
1797
1798                 /* Now do the handling for an existing target, if there is one */
1799
1800                 existingTarget = yaffs_FindObjectByName(newDir, newName);
1801                 if (existingTarget &&
1802                     existingTarget->variantType == YAFFS_OBJECT_TYPE_DIRECTORY &&
1803                     !list_empty(&existingTarget->variant.directoryVariant.children)) {
1804                         /* There is a target that is a non-empty directory, so we fail */
1805                         return YAFFS_FAIL;      /* EEXIST or ENOTEMPTY */
1806                 } else if (existingTarget && existingTarget != obj) {
1807                         /* Nuke the target first, using shadowing,
1808                          * but only if it isn't the same object
1809                          */
1810                         yaffs_ChangeObjectName(obj, newDir, newName, force,
1811                                                existingTarget->objectId);
1812                         yaffs_UnlinkObject(existingTarget);
1813                 }
1814
1815                 return yaffs_ChangeObjectName(obj, newDir, newName, 1, 0);
1816         }
1817         return YAFFS_FAIL;
1818 }
1819
1820 /*------------------------- Block Management and Page Allocation ----------------*/
1821
1822 static int yaffs_InitialiseBlocks(yaffs_Device * dev, int nBlocks)
1823 {
1824         dev->allocationBlock = -1;      /* force it to get a new one */
1825
1826         /* Todo we're assuming the malloc will pass. */
1827         dev->blockInfo = YMALLOC(nBlocks * sizeof(yaffs_BlockInfo));
1828         if(!dev->blockInfo){
1829                 dev->blockInfo = YMALLOC_ALT(nBlocks * sizeof(yaffs_BlockInfo));
1830                 dev->blockInfoAlt = 1;
1831         }
1832         else
1833                 dev->blockInfoAlt = 0;
1834
1835         /* Set up dynamic blockinfo stuff. */
1836         dev->chunkBitmapStride = (dev->nChunksPerBlock + 7) / 8;
1837         dev->chunkBits = YMALLOC(dev->chunkBitmapStride * nBlocks);
1838         if(!dev->chunkBits){
1839                 dev->chunkBits = YMALLOC_ALT(dev->chunkBitmapStride * nBlocks);
1840                 dev->chunkBitsAlt = 1;
1841         }
1842         else
1843                 dev->chunkBitsAlt = 0;
1844
1845         if (dev->blockInfo && dev->chunkBits) {
1846                 memset(dev->blockInfo, 0, nBlocks * sizeof(yaffs_BlockInfo));
1847                 memset(dev->chunkBits, 0, dev->chunkBitmapStride * nBlocks);
1848                 return YAFFS_OK;
1849         }
1850
1851         return YAFFS_FAIL;
1852
1853 }
1854
1855 static void yaffs_DeinitialiseBlocks(yaffs_Device * dev)
1856 {
1857         if(dev->blockInfoAlt)
1858                 YFREE_ALT(dev->blockInfo);
1859         else
1860                 YFREE(dev->blockInfo);
1861         dev->blockInfoAlt = 0;
1862
1863         dev->blockInfo = NULL;
1864
1865         if(dev->chunkBitsAlt)
1866                 YFREE_ALT(dev->chunkBits);
1867         else
1868                 YFREE(dev->chunkBits);
1869         dev->chunkBitsAlt = 0;
1870         dev->chunkBits = NULL;
1871 }
1872
1873 static int yaffs_BlockNotDisqualifiedFromGC(yaffs_Device * dev,
1874                                             yaffs_BlockInfo * bi)
1875 {
1876         int i;
1877         __u32 seq;
1878         yaffs_BlockInfo *b;
1879
1880         if (!dev->isYaffs2)
1881                 return 1;       /* disqualification only applies to yaffs2. */
1882
1883         if (!bi->hasShrinkHeader)
1884                 return 1;       /* can gc */
1885
1886         /* Find the oldest dirty sequence number if we don't know it and save it
1887          * so we don't have to keep recomputing it.
1888          */
1889         if (!dev->oldestDirtySequence) {
1890                 seq = dev->sequenceNumber;
1891
1892                 for (i = dev->internalStartBlock; i <= dev->internalEndBlock;
1893                      i++) {
1894                         b = yaffs_GetBlockInfo(dev, i);
1895                         if (b->blockState == YAFFS_BLOCK_STATE_FULL &&
1896                             (b->pagesInUse - b->softDeletions) <
1897                             dev->nChunksPerBlock && b->sequenceNumber < seq) {
1898                                 seq = b->sequenceNumber;
1899                         }
1900                 }
1901                 dev->oldestDirtySequence = seq;
1902         }
1903
1904         /* Can't do gc of this block if there are any blocks older than this one that have
1905          * discarded pages.
1906          */
1907         return (bi->sequenceNumber <= dev->oldestDirtySequence);
1908
1909         return 1;
1910
1911 }
1912
1913 /* FindDiretiestBlock is used to select the dirtiest block (or close enough)
1914  * for garbage collection.
1915  */
1916
1917 static int yaffs_FindBlockForGarbageCollection(yaffs_Device * dev,
1918                                                int aggressive)
1919 {
1920
1921         int b = dev->currentDirtyChecker;
1922
1923         int i;
1924         int iterations;
1925         int dirtiest = -1;
1926         int pagesInUse;
1927         yaffs_BlockInfo *bi;
1928         static int nonAggressiveSkip = 0;
1929
1930         /* If we're doing aggressive GC then we are happy to take a less-dirty block, and
1931          * search harder.
1932          * else (we're doing a leasurely gc), then we only bother to do this if the
1933          * block has only a few pages in use.
1934          */
1935
1936         nonAggressiveSkip--;
1937
1938         if (!aggressive && (nonAggressiveSkip > 0)) {
1939                 return -1;
1940         }
1941
1942         pagesInUse =
1943             (aggressive) ? dev->nChunksPerBlock : YAFFS_PASSIVE_GC_CHUNKS + 1;
1944
1945         if (aggressive) {
1946                 iterations =
1947                     dev->internalEndBlock - dev->internalStartBlock + 1;
1948         } else {
1949                 iterations =
1950                     dev->internalEndBlock - dev->internalStartBlock + 1;
1951                 iterations = iterations / 16;
1952                 if (iterations > 200) {
1953                         iterations = 200;
1954                 }
1955         }
1956
1957         for (i = 0; i <= iterations && pagesInUse > 0; i++) {
1958                 b++;
1959                 if (b < dev->internalStartBlock || b > dev->internalEndBlock) {
1960                         b = dev->internalStartBlock;
1961                 }
1962
1963                 if (b < dev->internalStartBlock || b > dev->internalEndBlock) {
1964                         T(YAFFS_TRACE_ERROR,
1965                           (TSTR("**>> Block %d is not valid" TENDSTR), b));
1966                         YBUG();
1967                 }
1968
1969                 bi = yaffs_GetBlockInfo(dev, b);
1970
1971                 if (bi->blockState == YAFFS_BLOCK_STATE_FULL &&
1972                     (bi->pagesInUse - bi->softDeletions) < pagesInUse &&
1973                     yaffs_BlockNotDisqualifiedFromGC(dev, bi)) {
1974                         dirtiest = b;
1975                         pagesInUse = (bi->pagesInUse - bi->softDeletions);
1976                 }
1977         }
1978
1979         dev->currentDirtyChecker = b;
1980
1981         if (dirtiest > 0) {
1982                 T(YAFFS_TRACE_GC,
1983                   (TSTR("GC Selected block %d with %d free" TENDSTR), dirtiest,
1984                    dev->nChunksPerBlock - pagesInUse));
1985         }
1986
1987         dev->oldestDirtySequence = 0;
1988
1989         if (dirtiest > 0) {
1990                 nonAggressiveSkip = 4;
1991         }
1992
1993         return dirtiest;
1994 }
1995
1996 static void yaffs_BlockBecameDirty(yaffs_Device * dev, int blockNo)
1997 {
1998         yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, blockNo);
1999
2000         int erasedOk = 0;
2001
2002         /* If the block is still healthy erase it and mark as clean.
2003          * If the block has had a data failure, then retire it.
2004          */
2005         bi->blockState = YAFFS_BLOCK_STATE_DIRTY;
2006
2007         if (!bi->needsRetiring) {
2008                 erasedOk = yaffs_EraseBlockInNAND(dev, blockNo);
2009                 if (!erasedOk) {
2010                         dev->nErasureFailures++;
2011                         T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
2012                           (TSTR("**>> Erasure failed %d" TENDSTR), blockNo));
2013                 }
2014         }
2015
2016         if (erasedOk && (yaffs_traceMask & YAFFS_TRACE_ERASE)) {
2017                 int i;
2018                 for (i = 0; i < dev->nChunksPerBlock; i++) {
2019                         if (!yaffs_CheckChunkErased
2020                             (dev, blockNo * dev->nChunksPerBlock + i)) {
2021                                 T(YAFFS_TRACE_ERROR,
2022                                   (TSTR
2023                                    (">>Block %d erasure supposedly OK, but chunk %d not erased"
2024                                     TENDSTR), blockNo, i));
2025                         }
2026                 }
2027         }
2028
2029         if (erasedOk) {
2030                 /* Clean it up... */
2031                 bi->blockState = YAFFS_BLOCK_STATE_EMPTY;
2032                 dev->nErasedBlocks++;
2033                 bi->pagesInUse = 0;
2034                 bi->softDeletions = 0;
2035                 bi->hasShrinkHeader = 0;
2036                 yaffs_ClearChunkBits(dev, blockNo);
2037
2038                 T(YAFFS_TRACE_ERASE,
2039                   (TSTR("Erased block %d" TENDSTR), blockNo));
2040         } else {
2041                 dev->nFreeChunks -= dev->nChunksPerBlock;       /* We lost a block of free space */
2042
2043                 yaffs_RetireBlock(dev, blockNo);
2044                 T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
2045                   (TSTR("**>> Block %d retired" TENDSTR), blockNo));
2046         }
2047 }
2048
2049 static int yaffs_FindBlockForAllocation(yaffs_Device * dev)
2050 {
2051         int i;
2052
2053         yaffs_BlockInfo *bi;
2054
2055         if (dev->nErasedBlocks < 1) {
2056                 /* Hoosterman we've got a problem.
2057                  * Can't get space to gc
2058                  */
2059                 T(YAFFS_TRACE_ERROR,
2060                   (TSTR("yaffs tragedy: no more eraased blocks" TENDSTR)));
2061
2062                 return -1;
2063         }
2064
2065         /* Find an empty block. */
2066
2067         for (i = dev->internalStartBlock; i <= dev->internalEndBlock; i++) {
2068                 dev->allocationBlockFinder++;
2069                 if (dev->allocationBlockFinder < dev->internalStartBlock
2070                     || dev->allocationBlockFinder > dev->internalEndBlock) {
2071                         dev->allocationBlockFinder = dev->internalStartBlock;
2072                 }
2073
2074                 bi = yaffs_GetBlockInfo(dev, dev->allocationBlockFinder);
2075
2076                 if (bi->blockState == YAFFS_BLOCK_STATE_EMPTY) {
2077                         bi->blockState = YAFFS_BLOCK_STATE_ALLOCATING;
2078                         dev->sequenceNumber++;
2079                         bi->sequenceNumber = dev->sequenceNumber;
2080                         dev->nErasedBlocks--;
2081                         T(YAFFS_TRACE_ALLOCATE,
2082                           (TSTR("Allocated block %d, seq  %d, %d left" TENDSTR),
2083                            dev->allocationBlockFinder, dev->sequenceNumber,
2084                            dev->nErasedBlocks));
2085                         return dev->allocationBlockFinder;
2086                 }
2087         }
2088
2089         T(YAFFS_TRACE_ALWAYS,
2090           (TSTR
2091            ("yaffs tragedy: no more eraased blocks, but there should have been %d"
2092             TENDSTR), dev->nErasedBlocks));
2093
2094         return -1;
2095 }
2096
2097
2098
2099 static int yaffs_CheckSpaceForAllocation(yaffs_Device * dev)
2100 {
2101         int reservedChunks = (dev->nReservedBlocks * dev->nChunksPerBlock);
2102         return (dev->nFreeChunks > reservedChunks);
2103 }
2104
2105 static int yaffs_AllocateChunk(yaffs_Device * dev, int useReserve)
2106 {
2107         int retVal;
2108         yaffs_BlockInfo *bi;
2109
2110         if (dev->allocationBlock < 0) {
2111                 /* Get next block to allocate off */
2112                 dev->allocationBlock = yaffs_FindBlockForAllocation(dev);
2113                 dev->allocationPage = 0;
2114         }
2115
2116         if (!useReserve && !yaffs_CheckSpaceForAllocation(dev)) {
2117                 /* Not enough space to allocate unless we're allowed to use the reserve. */
2118                 return -1;
2119         }
2120
2121         if (dev->nErasedBlocks < dev->nReservedBlocks
2122             && dev->allocationPage == 0) {
2123                 T(YAFFS_TRACE_ALLOCATE, (TSTR("Allocating reserve" TENDSTR)));
2124         }
2125
2126         /* Next page please.... */
2127         if (dev->allocationBlock >= 0) {
2128                 bi = yaffs_GetBlockInfo(dev, dev->allocationBlock);
2129
2130                 retVal = (dev->allocationBlock * dev->nChunksPerBlock) +
2131                     dev->allocationPage;
2132                 bi->pagesInUse++;
2133                 yaffs_SetChunkBit(dev, dev->allocationBlock,
2134                                   dev->allocationPage);
2135
2136                 dev->allocationPage++;
2137
2138                 dev->nFreeChunks--;
2139
2140                 /* If the block is full set the state to full */
2141                 if (dev->allocationPage >= dev->nChunksPerBlock) {
2142                         bi->blockState = YAFFS_BLOCK_STATE_FULL;
2143                         dev->allocationBlock = -1;
2144                 }
2145
2146                 return retVal;
2147         }
2148
2149         T(YAFFS_TRACE_ERROR,
2150           (TSTR("!!!!!!!!! Allocator out !!!!!!!!!!!!!!!!!" TENDSTR)));
2151
2152         return -1;
2153 }
2154
2155 static int yaffs_GetErasedChunks(yaffs_Device * dev)
2156 {
2157         int n;
2158
2159         n = dev->nErasedBlocks * dev->nChunksPerBlock;
2160
2161         if (dev->allocationBlock > 0) {
2162                 n += (dev->nChunksPerBlock - dev->allocationPage);
2163         }
2164
2165         return n;
2166
2167 }
2168
2169 static int yaffs_GarbageCollectBlock(yaffs_Device * dev, int block)
2170 {
2171         int oldChunk;
2172         int newChunk;
2173         int chunkInBlock;
2174         int markNAND;
2175         int retVal = YAFFS_OK;
2176         int cleanups = 0;
2177         int i;
2178
2179         int chunksBefore = yaffs_GetErasedChunks(dev);
2180         int chunksAfter;
2181
2182         yaffs_ExtendedTags tags;
2183
2184         yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, block);
2185
2186         yaffs_Object *object;
2187
2188         bi->blockState = YAFFS_BLOCK_STATE_COLLECTING;
2189
2190         T(YAFFS_TRACE_TRACING,
2191           (TSTR("Collecting block %d, in use %d, shrink %d, " TENDSTR), block,
2192            bi->pagesInUse, bi->hasShrinkHeader));
2193
2194         /*yaffs_VerifyFreeChunks(dev); */
2195
2196         bi->hasShrinkHeader = 0;        /* clear the flag so that the block can erase */
2197
2198         /* Take off the number of soft deleted entries because
2199          * they're going to get really deleted during GC.
2200          */
2201         dev->nFreeChunks -= bi->softDeletions;
2202
2203         dev->isDoingGC = 1;
2204
2205         if (!yaffs_StillSomeChunkBits(dev, block)) {
2206                 T(YAFFS_TRACE_TRACING,
2207                   (TSTR
2208                    ("Collecting block %d that has no chunks in use" TENDSTR),
2209                    block));
2210                 yaffs_BlockBecameDirty(dev, block);
2211         } else {
2212
2213                 __u8 *buffer = yaffs_GetTempBuffer(dev, __LINE__);
2214
2215                 for (chunkInBlock = 0, oldChunk = block * dev->nChunksPerBlock;
2216                      chunkInBlock < dev->nChunksPerBlock
2217                      && yaffs_StillSomeChunkBits(dev, block);
2218                      chunkInBlock++, oldChunk++) {
2219                         if (yaffs_CheckChunkBit(dev, block, chunkInBlock)) {
2220
2221                                 /* This page is in use and might need to be copied off */
2222
2223                                 markNAND = 1;
2224
2225                                 yaffs_InitialiseTags(&tags);
2226
2227                                 yaffs_ReadChunkWithTagsFromNAND(dev, oldChunk,
2228                                                                 buffer, &tags);
2229
2230                                 object =
2231                                     yaffs_FindObjectByNumber(dev,
2232                                                              tags.objectId);
2233
2234                                 T(YAFFS_TRACE_GC_DETAIL,
2235                                   (TSTR
2236                                    ("Collecting page %d, %d %d %d " TENDSTR),
2237                                    chunkInBlock, tags.objectId, tags.chunkId,
2238                                    tags.byteCount));
2239
2240                                 if (!object) {
2241                                         T(YAFFS_TRACE_ERROR,
2242                                           (TSTR
2243                                            ("page %d in gc has no object "
2244                                             TENDSTR), oldChunk));
2245                                 }
2246
2247                                 if (object && object->deleted
2248                                     && tags.chunkId != 0) {
2249                                         /* Data chunk in a deleted file, throw it away
2250                                          * It's a soft deleted data chunk,
2251                                          * No need to copy this, just forget about it and
2252                                          * fix up the object.
2253                                          */
2254
2255                                         object->nDataChunks--;
2256
2257                                         if (object->nDataChunks <= 0) {
2258                                                 /* remeber to clean up the object */
2259                                                 dev->gcCleanupList[cleanups] =
2260                                                     tags.objectId;
2261                                                 cleanups++;
2262                                         }
2263                                         markNAND = 0;
2264                                 } else if (0
2265                                            /* Todo object && object->deleted && object->nDataChunks == 0 */
2266                                            ) {
2267                                         /* Deleted object header with no data chunks.
2268                                          * Can be discarded and the file deleted.
2269                                          */
2270                                         object->chunkId = 0;
2271                                         yaffs_FreeTnode(object->myDev,
2272                                                         object->variant.
2273                                                         fileVariant.top);
2274                                         object->variant.fileVariant.top = NULL;
2275                                         yaffs_DoGenericObjectDeletion(object);
2276
2277                                 } else if (object) {
2278                                         /* It's either a data chunk in a live file or
2279                                          * an ObjectHeader, so we're interested in it.
2280                                          * NB Need to keep the ObjectHeaders of deleted files
2281                                          * until the whole file has been deleted off
2282                                          */
2283                                         tags.serialNumber++;
2284
2285                                         dev->nGCCopies++;
2286
2287                                         if (tags.chunkId == 0) {
2288                                                 /* It is an object Id,
2289                                                  * We need to nuke the shrinkheader flags first
2290                                                  * We no longer want the shrinkHeader flag since its work is done
2291                                                  * and if it is left in place it will mess up scanning.
2292                                                  * Also, clear out any shadowing stuff
2293                                                  */
2294
2295                                                 yaffs_ObjectHeader *oh;
2296                                                 oh = (yaffs_ObjectHeader *)buffer;
2297                                                 oh->isShrink = 0;
2298                                                 oh->shadowsObject = -1;
2299                                                 tags.extraShadows = 0;
2300                                                 tags.extraIsShrinkHeader = 0;
2301                                         }
2302
2303                                         newChunk =
2304                                             yaffs_WriteNewChunkWithTagsToNAND(dev, buffer, &tags, 1);
2305
2306                                         if (newChunk < 0) {
2307                                                 retVal = YAFFS_FAIL;
2308                                         } else {
2309
2310                                                 /* Ok, now fix up the Tnodes etc. */
2311
2312                                                 if (tags.chunkId == 0) {
2313                                                         /* It's a header */
2314                                                         object->chunkId =  newChunk;
2315                                                         object->serial =   tags.serialNumber;
2316                                                 } else {
2317                                                         /* It's a data chunk */
2318                                                         yaffs_PutChunkIntoFile
2319                                                             (object,
2320                                                              tags.chunkId,
2321                                                              newChunk, 0);
2322                                                 }
2323                                         }
2324                                 }
2325
2326                                 yaffs_DeleteChunk(dev, oldChunk, markNAND, __LINE__);
2327
2328                         }
2329                 }
2330
2331                 yaffs_ReleaseTempBuffer(dev, buffer, __LINE__);
2332
2333
2334                 /* Do any required cleanups */
2335                 for (i = 0; i < cleanups; i++) {
2336                         /* Time to delete the file too */
2337                         object =
2338                             yaffs_FindObjectByNumber(dev,
2339                                                      dev->gcCleanupList[i]);
2340                         if (object) {
2341                                 yaffs_FreeTnode(dev,
2342                                                 object->variant.fileVariant.
2343                                                 top);
2344                                 object->variant.fileVariant.top = NULL;
2345                                 T(YAFFS_TRACE_GC,
2346                                   (TSTR
2347                                    ("yaffs: About to finally delete object %d"
2348                                     TENDSTR), object->objectId));
2349                                 yaffs_DoGenericObjectDeletion(object);
2350                                 object->myDev->nDeletedFiles--;
2351                         }
2352
2353                 }
2354
2355         }
2356
2357         if (chunksBefore >= (chunksAfter = yaffs_GetErasedChunks(dev))) {
2358                 T(YAFFS_TRACE_GC,
2359                   (TSTR
2360                    ("gc did not increase free chunks before %d after %d"
2361                     TENDSTR), chunksBefore, chunksAfter));
2362         }
2363
2364         dev->isDoingGC = 0;
2365
2366         return YAFFS_OK;
2367 }
2368
2369 /* New garbage collector
2370  * If we're very low on erased blocks then we do aggressive garbage collection
2371  * otherwise we do "leasurely" garbage collection.
2372  * Aggressive gc looks further (whole array) and will accept less dirty blocks.
2373  * Passive gc only inspects smaller areas and will only accept more dirty blocks.
2374  *
2375  * The idea is to help clear out space in a more spread-out manner.
2376  * Dunno if it really does anything useful.
2377  */
2378 static int yaffs_CheckGarbageCollection(yaffs_Device * dev)
2379 {
2380         int block;
2381         int aggressive;
2382         int gcOk = YAFFS_OK;
2383         int maxTries = 0;
2384
2385         if (dev->isDoingGC) {
2386                 /* Bail out so we don't get recursive gc */
2387                 return YAFFS_OK;
2388         }
2389
2390         /* This loop should pass the first time.
2391          * We'll only see looping here if the erase of the collected block fails.
2392          */
2393
2394         do {
2395                 maxTries++;
2396                 if (dev->nErasedBlocks < dev->nReservedBlocks) {
2397                         /* We need a block soon...*/
2398                         aggressive = 1;
2399                 } else {
2400                         /* We're in no hurry */
2401                         aggressive = 0;
2402                 }
2403
2404                 block = yaffs_FindBlockForGarbageCollection(dev, aggressive);
2405
2406                 if (block > 0) {
2407                         dev->garbageCollections++;
2408                         if (!aggressive) {
2409                                 dev->passiveGarbageCollections++;
2410                         }
2411
2412                         T(YAFFS_TRACE_GC,
2413                           (TSTR
2414                            ("yaffs: GC erasedBlocks %d aggressive %d" TENDSTR),
2415                            dev->nErasedBlocks, aggressive));
2416
2417                         gcOk = yaffs_GarbageCollectBlock(dev, block);
2418                 }
2419
2420                 if (dev->nErasedBlocks < (dev->nReservedBlocks) && block > 0) {
2421                         T(YAFFS_TRACE_GC,
2422                           (TSTR
2423                            ("yaffs: GC !!!no reclaim!!! erasedBlocks %d after try %d block %d"
2424                             TENDSTR), dev->nErasedBlocks, maxTries, block));
2425                 }
2426         } while ((dev->nErasedBlocks < dev->nReservedBlocks) && (block > 0)
2427                  && (maxTries < 2));
2428
2429         return aggressive ? gcOk : YAFFS_OK;
2430 }
2431
2432 /*-------------------------  TAGS --------------------------------*/
2433
2434 static int yaffs_TagsMatch(const yaffs_ExtendedTags * tags, int objectId,
2435                            int chunkInObject)
2436 {
2437         return (tags->chunkId == chunkInObject &&
2438                 tags->objectId == objectId && !tags->chunkDeleted) ? 1 : 0;
2439
2440 }
2441
2442
2443 /*-------------------- Data file manipulation -----------------*/
2444
2445 static int yaffs_FindChunkInFile(yaffs_Object * in, int chunkInInode,
2446                                  yaffs_ExtendedTags * tags)
2447 {
2448         /*Get the Tnode, then get the level 0 offset chunk offset */
2449         yaffs_Tnode *tn;
2450         int theChunk = -1;
2451         yaffs_ExtendedTags localTags;
2452         int retVal = -1;
2453
2454         yaffs_Device *dev = in->myDev;
2455
2456         if (!tags) {
2457                 /* Passed a NULL, so use our own tags space */
2458                 tags = &localTags;
2459         }
2460
2461         tn = yaffs_FindLevel0Tnode(dev, &in->variant.fileVariant, chunkInInode);
2462
2463         if (tn) {
2464                 theChunk = yaffs_GetChunkGroupBase(dev,tn,chunkInInode);
2465
2466                 retVal =
2467                     yaffs_FindChunkInGroup(dev, theChunk, tags, in->objectId,
2468                                            chunkInInode);
2469         }
2470         return retVal;
2471 }
2472
2473 static int yaffs_FindAndDeleteChunkInFile(yaffs_Object * in, int chunkInInode,
2474                                           yaffs_ExtendedTags * tags)
2475 {
2476         /* Get the Tnode, then get the level 0 offset chunk offset */
2477         yaffs_Tnode *tn;
2478         int theChunk = -1;
2479         yaffs_ExtendedTags localTags;
2480
2481         yaffs_Device *dev = in->myDev;
2482         int retVal = -1;
2483
2484         if (!tags) {
2485                 /* Passed a NULL, so use our own tags space */
2486                 tags = &localTags;
2487         }
2488
2489         tn = yaffs_FindLevel0Tnode(dev, &in->variant.fileVariant, chunkInInode);
2490
2491         if (tn) {
2492
2493                 theChunk = yaffs_GetChunkGroupBase(dev,tn,chunkInInode);
2494
2495                 retVal =
2496                     yaffs_FindChunkInGroup(dev, theChunk, tags, in->objectId,
2497                                            chunkInInode);
2498
2499                 /* Delete the entry in the filestructure (if found) */
2500                 if (retVal != -1) {
2501                         yaffs_PutLevel0Tnode(dev,tn,chunkInInode,0);
2502                 }
2503         } else {
2504                 /*T(("No level 0 found for %d\n", chunkInInode)); */
2505         }
2506
2507         if (retVal == -1) {
2508                 /* T(("Could not find %d to delete\n",chunkInInode)); */
2509         }
2510         return retVal;
2511 }
2512
2513 #ifdef YAFFS_PARANOID
2514
2515 static int yaffs_CheckFileSanity(yaffs_Object * in)
2516 {
2517         int chunk;
2518         int nChunks;
2519         int fSize;
2520         int failed = 0;
2521         int objId;
2522         yaffs_Tnode *tn;
2523         yaffs_Tags localTags;
2524         yaffs_Tags *tags = &localTags;
2525         int theChunk;
2526         int chunkDeleted;
2527
2528         if (in->variantType != YAFFS_OBJECT_TYPE_FILE) {
2529                 /* T(("Object not a file\n")); */
2530                 return YAFFS_FAIL;
2531         }
2532
2533         objId = in->objectId;
2534         fSize = in->variant.fileVariant.fileSize;
2535         nChunks =
2536             (fSize + in->myDev->nBytesPerChunk - 1) / in->myDev->nBytesPerChunk;
2537
2538         for (chunk = 1; chunk <= nChunks; chunk++) {
2539                 tn = yaffs_FindLevel0Tnode(in->myDev, &in->variant.fileVariant,
2540                                            chunk);
2541
2542                 if (tn) {
2543
2544                         theChunk = yaffs_GetChunkGroupBase(dev,tn,chunk);
2545
2546                         if (yaffs_CheckChunkBits
2547                             (dev, theChunk / dev->nChunksPerBlock,
2548                              theChunk % dev->nChunksPerBlock)) {
2549
2550                                 yaffs_ReadChunkTagsFromNAND(in->myDev, theChunk,
2551                                                             tags,
2552                                                             &chunkDeleted);
2553                                 if (yaffs_TagsMatch
2554                                     (tags, in->objectId, chunk, chunkDeleted)) {
2555                                         /* found it; */
2556
2557                                 }
2558                         } else {
2559
2560                                 failed = 1;
2561                         }
2562
2563                 } else {
2564                         /* T(("No level 0 found for %d\n", chunk)); */
2565                 }
2566         }
2567
2568         return failed ? YAFFS_FAIL : YAFFS_OK;
2569 }
2570
2571 #endif
2572
2573 static int yaffs_PutChunkIntoFile(yaffs_Object * in, int chunkInInode,
2574                                   int chunkInNAND, int inScan)
2575 {
2576         /* NB inScan is zero unless scanning.
2577          * For forward scanning, inScan is > 0;
2578          * for backward scanning inScan is < 0
2579          */
2580
2581         yaffs_Tnode *tn;
2582         yaffs_Device *dev = in->myDev;
2583         int existingChunk;
2584         yaffs_ExtendedTags existingTags;
2585         yaffs_ExtendedTags newTags;
2586         unsigned existingSerial, newSerial;
2587
2588         if (in->variantType != YAFFS_OBJECT_TYPE_FILE) {
2589                 /* Just ignore an attempt at putting a chunk into a non-file during scanning
2590                  * If it is not during Scanning then something went wrong!
2591                  */
2592                 if (!inScan) {
2593                         T(YAFFS_TRACE_ERROR,
2594                           (TSTR
2595                            ("yaffs tragedy:attempt to put data chunk into a non-file"
2596                             TENDSTR)));
2597                         YBUG();
2598                 }
2599
2600                 yaffs_DeleteChunk(dev, chunkInNAND, 1, __LINE__);
2601                 return YAFFS_OK;
2602         }
2603
2604         tn = yaffs_AddOrFindLevel0Tnode(dev, &in->variant.fileVariant,
2605                                         chunkInInode);
2606         if (!tn) {
2607                 return YAFFS_FAIL;
2608         }
2609
2610         existingChunk = yaffs_GetChunkGroupBase(dev,tn,chunkInInode);
2611
2612         if (inScan != 0) {
2613                 /* If we're scanning then we need to test for duplicates
2614                  * NB This does not need to be efficient since it should only ever
2615                  * happen when the power fails during a write, then only one
2616                  * chunk should ever be affected.
2617                  *
2618                  * Correction for YAFFS2: This could happen quite a lot and we need to think about efficiency! TODO
2619                  * Update: For backward scanning we don't need to re-read tags so this is quite cheap.
2620                  */
2621
2622                 if (existingChunk != 0) {
2623                         /* NB Right now existing chunk will not be real chunkId if the device >= 32MB
2624                          *    thus we have to do a FindChunkInFile to get the real chunk id.
2625                          *
2626                          * We have a duplicate now we need to decide which one to use:
2627                          *
2628                          * Backwards scanning YAFFS2: The old one is what we use, dump the new one.
2629                          * Forward scanning YAFFS2: The new one is what we use, dump the old one.
2630                          * YAFFS1: Get both sets of tags and compare serial numbers.
2631                          */
2632
2633                         if (inScan > 0) {
2634                                 /* Only do this for forward scanning */
2635                                 yaffs_ReadChunkWithTagsFromNAND(dev,
2636                                                                 chunkInNAND,
2637                                                                 NULL, &newTags);
2638
2639                                 /* Do a proper find */
2640                                 existingChunk =
2641                                     yaffs_FindChunkInFile(in, chunkInInode,
2642                                                           &existingTags);
2643                         }
2644
2645                         if (existingChunk <= 0) {
2646                                 /*Hoosterman - how did this happen? */
2647
2648                                 T(YAFFS_TRACE_ERROR,
2649                                   (TSTR
2650                                    ("yaffs tragedy: existing chunk < 0 in scan"
2651                                     TENDSTR)));
2652
2653                         }
2654
2655                         /* NB The deleted flags should be false, otherwise the chunks will
2656                          * not be loaded during a scan
2657                          */
2658
2659                         newSerial = newTags.serialNumber;
2660                         existingSerial = existingTags.serialNumber;
2661
2662                         if ((inScan > 0) &&
2663                             (in->myDev->isYaffs2 ||
2664                              existingChunk <= 0 ||
2665                              ((existingSerial + 1) & 3) == newSerial)) {
2666                                 /* Forward scanning.
2667                                  * Use new
2668                                  * Delete the old one and drop through to update the tnode
2669                                  */
2670                                 yaffs_DeleteChunk(dev, existingChunk, 1,
2671                                                   __LINE__);
2672                         } else {
2673                                 /* Backward scanning or we want to use the existing one
2674                                  * Use existing.
2675                                  * Delete the new one and return early so that the tnode isn't changed
2676                                  */
2677                                 yaffs_DeleteChunk(dev, chunkInNAND, 1,
2678                                                   __LINE__);
2679                                 return YAFFS_OK;
2680                         }
2681                 }
2682
2683         }
2684
2685         if (existingChunk == 0) {
2686                 in->nDataChunks++;
2687         }
2688
2689         yaffs_PutLevel0Tnode(dev,tn,chunkInInode,chunkInNAND);
2690
2691         return YAFFS_OK;
2692 }
2693
2694 static int yaffs_ReadChunkDataFromObject(yaffs_Object * in, int chunkInInode,
2695                                          __u8 * buffer)
2696 {
2697         int chunkInNAND = yaffs_FindChunkInFile(in, chunkInInode, NULL);
2698
2699         if (chunkInNAND >= 0) {
2700                 return yaffs_ReadChunkWithTagsFromNAND(in->myDev, chunkInNAND,
2701                                                        buffer, NULL);
2702         } else {
2703                 T(YAFFS_TRACE_NANDACCESS,
2704                   (TSTR("Chunk %d not found zero instead" TENDSTR),
2705                    chunkInNAND));
2706                 /* get sane (zero) data if you read a hole */
2707                 memset(buffer, 0, in->myDev->nBytesPerChunk);
2708                 return 0;
2709         }
2710
2711 }
2712
2713 void yaffs_DeleteChunk(yaffs_Device * dev, int chunkId, int markNAND, int lyn)
2714 {
2715         int block;
2716         int page;
2717         yaffs_ExtendedTags tags;
2718         yaffs_BlockInfo *bi;
2719
2720         if (chunkId <= 0)
2721                 return;
2722
2723         dev->nDeletions++;
2724         block = chunkId / dev->nChunksPerBlock;
2725         page = chunkId % dev->nChunksPerBlock;
2726
2727         bi = yaffs_GetBlockInfo(dev, block);
2728
2729         T(YAFFS_TRACE_DELETION,
2730           (TSTR("line %d delete of chunk %d" TENDSTR), lyn, chunkId));
2731
2732         if (markNAND &&
2733             bi->blockState != YAFFS_BLOCK_STATE_COLLECTING && !dev->isYaffs2) {
2734
2735                 yaffs_InitialiseTags(&tags);
2736
2737                 tags.chunkDeleted = 1;
2738
2739                 yaffs_WriteChunkWithTagsToNAND(dev, chunkId, NULL, &tags);
2740                 yaffs_HandleUpdateChunk(dev, chunkId, &tags);
2741         } else {
2742                 dev->nUnmarkedDeletions++;
2743         }
2744
2745         /* Pull out of the management area.
2746          * If the whole block became dirty, this will kick off an erasure.
2747          */
2748         if (bi->blockState == YAFFS_BLOCK_STATE_ALLOCATING ||
2749             bi->blockState == YAFFS_BLOCK_STATE_FULL ||
2750             bi->blockState == YAFFS_BLOCK_STATE_NEEDS_SCANNING ||
2751             bi->blockState == YAFFS_BLOCK_STATE_COLLECTING) {
2752                 dev->nFreeChunks++;
2753
2754                 yaffs_ClearChunkBit(dev, block, page);
2755
2756                 bi->pagesInUse--;
2757
2758                 if (bi->pagesInUse == 0 &&
2759                     !bi->hasShrinkHeader &&
2760                     bi->blockState != YAFFS_BLOCK_STATE_ALLOCATING &&
2761                     bi->blockState != YAFFS_BLOCK_STATE_NEEDS_SCANNING) {
2762                         yaffs_BlockBecameDirty(dev, block);
2763                 }
2764
2765         } else {
2766                 /* T(("Bad news deleting chunk %d\n",chunkId)); */
2767         }
2768
2769 }
2770
2771 static int yaffs_WriteChunkDataToObject(yaffs_Object * in, int chunkInInode,
2772                                         const __u8 * buffer, int nBytes,
2773                                         int useReserve)
2774 {
2775         /* Find old chunk Need to do this to get serial number
2776          * Write new one and patch into tree.
2777          * Invalidate old tags.
2778          */
2779
2780         int prevChunkId;
2781         yaffs_ExtendedTags prevTags;
2782
2783         int newChunkId;
2784         yaffs_ExtendedTags newTags;
2785
2786         yaffs_Device *dev = in->myDev;
2787
2788         yaffs_CheckGarbageCollection(dev);
2789
2790         /* Get the previous chunk at this location in the file if it exists */
2791         prevChunkId = yaffs_FindChunkInFile(in, chunkInInode, &prevTags);
2792
2793         /* Set up new tags */
2794         yaffs_InitialiseTags(&newTags);
2795
2796         newTags.chunkId = chunkInInode;
2797         newTags.objectId = in->objectId;
2798         newTags.serialNumber =
2799             (prevChunkId >= 0) ? prevTags.serialNumber + 1 : 1;
2800         newTags.byteCount = nBytes;
2801
2802         newChunkId =
2803             yaffs_WriteNewChunkWithTagsToNAND(dev, buffer, &newTags,
2804                                               useReserve);
2805
2806         if (newChunkId >= 0) {
2807                 yaffs_PutChunkIntoFile(in, chunkInInode, newChunkId, 0);
2808
2809                 if (prevChunkId >= 0) {
2810                         yaffs_DeleteChunk(dev, prevChunkId, 1, __LINE__);
2811
2812                 }
2813
2814                 yaffs_CheckFileSanity(in);
2815         }
2816         return newChunkId;
2817
2818 }
2819
2820 /* UpdateObjectHeader updates the header on NAND for an object.
2821  * If name is not NULL, then that new name is used.
2822  */
2823 int yaffs_UpdateObjectHeader(yaffs_Object * in, const YCHAR * name, int force,
2824                              int isShrink, int shadows)
2825 {
2826
2827         yaffs_BlockInfo *bi;
2828
2829         yaffs_Device *dev = in->myDev;
2830
2831         int prevChunkId;
2832         int retVal = 0;
2833
2834         int newChunkId;
2835         yaffs_ExtendedTags newTags;
2836
2837         __u8 *buffer = NULL;
2838         YCHAR oldName[YAFFS_MAX_NAME_LENGTH + 1];
2839
2840         yaffs_ObjectHeader *oh = NULL;
2841
2842         if (!in->fake || force) {
2843
2844                 yaffs_CheckGarbageCollection(dev);
2845
2846                 buffer = yaffs_GetTempBuffer(in->myDev, __LINE__);
2847                 oh = (yaffs_ObjectHeader *) buffer;
2848
2849                 prevChunkId = in->chunkId;
2850
2851                 if (prevChunkId >= 0) {
2852                         yaffs_ReadChunkWithTagsFromNAND(dev, prevChunkId,
2853                                                         buffer, NULL);
2854                         memcpy(oldName, oh->name, sizeof(oh->name));
2855                 }
2856
2857                 memset(buffer, 0xFF, dev->nBytesPerChunk);
2858
2859                 oh->type = in->variantType;
2860                 oh->yst_mode = in->yst_mode;
2861                 oh->shadowsObject = shadows;
2862
2863 #ifdef CONFIG_YAFFS_WINCE
2864                 oh->win_atime[0] = in->win_atime[0];
2865                 oh->win_ctime[0] = in->win_ctime[0];
2866                 oh->win_mtime[0] = in->win_mtime[0];
2867                 oh->win_atime[1] = in->win_atime[1];
2868                 oh->win_ctime[1] = in->win_ctime[1];
2869                 oh->win_mtime[1] = in->win_mtime[1];
2870 #else
2871                 oh->yst_uid = in->yst_uid;
2872                 oh->yst_gid = in->yst_gid;
2873                 oh->yst_atime = in->yst_atime;
2874                 oh->yst_mtime = in->yst_mtime;
2875                 oh->yst_ctime = in->yst_ctime;
2876                 oh->yst_rdev = in->yst_rdev;
2877 #endif
2878                 if (in->parent) {
2879                         oh->parentObjectId = in->parent->objectId;
2880                 } else {
2881                         oh->parentObjectId = 0;
2882                 }
2883
2884                 if (name && *name) {
2885                         memset(oh->name, 0, sizeof(oh->name));
2886                         yaffs_strncpy(oh->name, name, YAFFS_MAX_NAME_LENGTH);
2887                 } else if (prevChunkId) {
2888                         memcpy(oh->name, oldName, sizeof(oh->name));
2889                 } else {
2890                         memset(oh->name, 0, sizeof(oh->name));
2891                 }
2892
2893                 oh->isShrink = isShrink;
2894
2895                 switch (in->variantType) {
2896                 case YAFFS_OBJECT_TYPE_UNKNOWN:
2897                         /* Should not happen */
2898                         break;
2899                 case YAFFS_OBJECT_TYPE_FILE:
2900                         oh->fileSize =
2901                             (oh->parentObjectId == YAFFS_OBJECTID_DELETED
2902                              || oh->parentObjectId ==
2903                              YAFFS_OBJECTID_UNLINKED) ? 0 : in->variant.
2904                             fileVariant.fileSize;
2905                         break;
2906                 case YAFFS_OBJECT_TYPE_HARDLINK:
2907                         oh->equivalentObjectId =
2908                             in->variant.hardLinkVariant.equivalentObjectId;
2909                         break;
2910                 case YAFFS_OBJECT_TYPE_SPECIAL:
2911                         /* Do nothing */
2912                         break;
2913                 case YAFFS_OBJECT_TYPE_DIRECTORY:
2914                         /* Do nothing */
2915                         break;
2916                 case YAFFS_OBJECT_TYPE_SYMLINK:
2917                         yaffs_strncpy(oh->alias,
2918                                       in->variant.symLinkVariant.alias,
2919                                       YAFFS_MAX_ALIAS_LENGTH);
2920                         oh->alias[YAFFS_MAX_ALIAS_LENGTH] = 0;
2921                         break;
2922                 }
2923
2924                 /* Tags */
2925                 yaffs_InitialiseTags(&newTags);
2926                 in->serial++;
2927                 newTags.chunkId = 0;
2928                 newTags.objectId = in->objectId;
2929                 newTags.serialNumber = in->serial;
2930
2931                 /* Add extra info for file header */
2932
2933                 newTags.extraHeaderInfoAvailable = 1;
2934                 newTags.extraParentObjectId = oh->parentObjectId;
2935                 newTags.extraFileLength = oh->fileSize;
2936                 newTags.extraIsShrinkHeader = oh->isShrink;
2937                 newTags.extraEquivalentObjectId = oh->equivalentObjectId;
2938                 newTags.extraShadows = (oh->shadowsObject > 0) ? 1 : 0;
2939                 newTags.extraObjectType = in->variantType;
2940
2941                 /* Create new chunk in NAND */
2942                 newChunkId =
2943                     yaffs_WriteNewChunkWithTagsToNAND(dev, buffer, &newTags,
2944                                                       (prevChunkId >= 0) ? 1 : 0);
2945
2946                 if (newChunkId >= 0) {
2947
2948                         in->chunkId = newChunkId;
2949
2950                         if (prevChunkId >= 0) {
2951                                 yaffs_DeleteChunk(dev, prevChunkId, 1,
2952                                                   __LINE__);
2953                         }
2954
2955                         in->dirty = 0;
2956
2957                         /* If this was a shrink, then mark the block that the chunk lives on */
2958                         if (isShrink) {
2959                                 bi = yaffs_GetBlockInfo(in->myDev,
2960                                                         newChunkId /in->myDev-> nChunksPerBlock);
2961                                 bi->hasShrinkHeader = 1;
2962                         }
2963
2964                 }
2965
2966                 retVal = newChunkId;
2967
2968         }
2969
2970         if (buffer)
2971                 yaffs_ReleaseTempBuffer(dev, buffer, __LINE__);
2972
2973         return retVal;
2974 }
2975
2976 /*------------------------ Short Operations Cache ----------------------------------------
2977  *   In many situations where there is no high level buffering (eg WinCE) a lot of
2978  *   reads might be short sequential reads, and a lot of writes may be short
2979  *   sequential writes. eg. scanning/writing a jpeg file.
2980  *   In these cases, a short read/write cache can provide a huge perfomance benefit
2981  *   with dumb-as-a-rock code.
2982  *   In Linux, the page cache provides read buffering aand the short op cache provides write
2983  *   buffering.
2984  *
2985  *   There are a limited number (~10) of cache chunks per device so that we don't
2986  *   need a very intelligent search.
2987  */
2988
2989 static void yaffs_FlushFilesChunkCache(yaffs_Object * obj)
2990 {
2991         yaffs_Device *dev = obj->myDev;
2992         int lowest = -99;       /* Stop compiler whining. */
2993         int i;
2994         yaffs_ChunkCache *cache;
2995         int chunkWritten = 0;
2996         int nCaches = obj->myDev->nShortOpCaches;
2997
2998         if (nCaches > 0) {
2999                 do {
3000                         cache = NULL;
3001
3002                         /* Find the dirty cache for this object with the lowest chunk id. */
3003                         for (i = 0; i < nCaches; i++) {
3004                                 if (dev->srCache[i].object == obj &&
3005                                     dev->srCache[i].dirty) {
3006                                         if (!cache
3007                                             || dev->srCache[i].chunkId <
3008                                             lowest) {
3009                                                 cache = &dev->srCache[i];
3010                                                 lowest = cache->chunkId;
3011                                         }
3012                                 }
3013                         }
3014
3015                         if (cache && !cache->locked) {
3016                                 /* Write it out and free it up */
3017
3018                                 chunkWritten =
3019                                     yaffs_WriteChunkDataToObject(cache->object,
3020                                                                  cache->chunkId,
3021                                                                  cache->data,
3022                                                                  cache->nBytes,
3023                                                                  1);
3024                                 cache->dirty = 0;
3025                                 cache->object = NULL;
3026                         }
3027
3028                 } while (cache && chunkWritten > 0);
3029
3030                 if (cache) {
3031                         /* Hoosterman, disk full while writing cache out. */
3032                         T(YAFFS_TRACE_ERROR,
3033                           (TSTR("yaffs tragedy: no space during cache write" TENDSTR)));
3034
3035                 }
3036         }
3037
3038 }
3039
3040 /* Grab us a cache chunk for use.
3041  * First look for an empty one.
3042  * Then look for the least recently used non-dirty one.
3043  * Then look for the least recently used dirty one...., flush and look again.
3044  */
3045 static yaffs_ChunkCache *yaffs_GrabChunkCacheWorker(yaffs_Device * dev)
3046 {
3047         int i;
3048         int usage;
3049         int theOne;
3050
3051         if (dev->nShortOpCaches > 0) {
3052                 for (i = 0; i < dev->nShortOpCaches; i++) {
3053                         if (!dev->srCache[i].object)
3054                                 return &dev->srCache[i];
3055                 }
3056
3057                 return NULL;
3058
3059                 theOne = -1;
3060                 usage = 0;      /* just to stop the compiler grizzling */
3061
3062                 for (i = 0; i < dev->nShortOpCaches; i++) {
3063                         if (!dev->srCache[i].dirty &&
3064                             ((dev->srCache[i].lastUse < usage && theOne >= 0) ||
3065                              theOne < 0)) {
3066                                 usage = dev->srCache[i].lastUse;
3067                                 theOne = i;
3068                         }
3069                 }
3070
3071
3072                 return theOne >= 0 ? &dev->srCache[theOne] : NULL;
3073         } else {
3074                 return NULL;
3075         }
3076
3077 }
3078
3079 static yaffs_ChunkCache *yaffs_GrabChunkCache(yaffs_Device * dev)
3080 {
3081         yaffs_ChunkCache *cache;
3082         yaffs_Object *theObj;
3083         int usage;
3084         int i;
3085         int pushout;
3086
3087         if (dev->nShortOpCaches > 0) {
3088                 /* Try find a non-dirty one... */
3089
3090                 cache = yaffs_GrabChunkCacheWorker(dev);
3091
3092                 if (!cache) {
3093                         /* They were all dirty, find the last recently used object and flush
3094                          * its cache, then  find again.
3095                          * NB what's here is not very accurate, we actually flush the object
3096                          * the last recently used page.
3097                          */
3098
3099                         /* With locking we can't assume we can use entry zero */
3100
3101                         theObj = NULL;
3102                         usage = -1;
3103                         cache = NULL;
3104                         pushout = -1;
3105
3106                         for (i = 0; i < dev->nShortOpCaches; i++) {
3107                                 if (dev->srCache[i].object &&
3108                                     !dev->srCache[i].locked &&
3109                                     (dev->srCache[i].lastUse < usage || !cache))
3110                                 {
3111                                         usage = dev->srCache[i].lastUse;
3112                                         theObj = dev->srCache[i].object;
3113                                         cache = &dev->srCache[i];
3114                                         pushout = i;
3115                                 }
3116                         }
3117
3118                         if (!cache || cache->dirty) {
3119                                 /* Flush and try again */
3120                                 yaffs_FlushFilesChunkCache(theObj);
3121                                 cache = yaffs_GrabChunkCacheWorker(dev);
3122                         }
3123
3124                 }
3125                 return cache;
3126         } else
3127                 return NULL;
3128
3129 }
3130
3131 /* Find a cached chunk */
3132 static yaffs_ChunkCache *yaffs_FindChunkCache(const yaffs_Object * obj,
3133                                               int chunkId)
3134 {
3135         yaffs_Device *dev = obj->myDev;
3136         int i;
3137         if (dev->nShortOpCaches > 0) {
3138                 for (i = 0; i < dev->nShortOpCaches; i++) {
3139                         if (dev->srCache[i].object == obj &&
3140                             dev->srCache[i].chunkId == chunkId) {
3141                                 dev->cacheHits++;
3142
3143                                 return &dev->srCache[i];
3144                         }
3145                 }
3146         }
3147         return NULL;
3148 }
3149
3150 /* Mark the chunk for the least recently used algorithym */
3151 static void yaffs_UseChunkCache(yaffs_Device * dev, yaffs_ChunkCache * cache,
3152                                 int isAWrite)
3153 {
3154
3155         if (dev->nShortOpCaches > 0) {
3156                 if (dev->srLastUse < 0 || dev->srLastUse > 100000000) {
3157                         /* Reset the cache usages */
3158                         int i;
3159                         for (i = 1; i < dev->nShortOpCaches; i++) {
3160                                 dev->srCache[i].lastUse = 0;
3161                         }
3162                         dev->srLastUse = 0;
3163                 }
3164
3165                 dev->srLastUse++;
3166
3167                 cache->lastUse = dev->srLastUse;
3168
3169                 if (isAWrite) {
3170                         cache->dirty = 1;
3171                 }
3172         }
3173 }
3174
3175 /* Invalidate a single cache page.
3176  * Do this when a whole page gets written,
3177  * ie the short cache for this page is no longer valid.
3178  */
3179 static void yaffs_InvalidateChunkCache(yaffs_Object * object, int chunkId)
3180 {
3181         if (object->myDev->nShortOpCaches > 0) {
3182                 yaffs_ChunkCache *cache = yaffs_FindChunkCache(object, chunkId);
3183
3184                 if (cache) {
3185                         cache->object = NULL;
3186                 }
3187         }
3188 }
3189
3190 /* Invalidate all the cache pages associated with this object
3191  * Do this whenever ther file is deleted or resized.
3192  */
3193 static void yaffs_InvalidateWholeChunkCache(yaffs_Object * in)
3194 {
3195         int i;
3196         yaffs_Device *dev = in->myDev;
3197
3198         if (dev->nShortOpCaches > 0) {
3199                 /* Invalidate it. */
3200                 for (i = 0; i < dev->nShortOpCaches; i++) {
3201                         if (dev->srCache[i].object == in) {
3202                                 dev->srCache[i].object = NULL;
3203                         }
3204                 }
3205         }
3206 }
3207
3208 /*--------------------- File read/write ------------------------
3209  * Read and write have very similar structures.
3210  * In general the read/write has three parts to it
3211  * An incomplete chunk to start with (if the read/write is not chunk-aligned)
3212  * Some complete chunks
3213  * An incomplete chunk to end off with
3214  *
3215  * Curve-balls: the first chunk might also be the last chunk.
3216  */
3217
3218 int yaffs_ReadDataFromFile(yaffs_Object * in, __u8 * buffer, __u32 offset,
3219                            int nBytes)
3220 {
3221
3222         int chunk;
3223         int start;
3224         int nToCopy;
3225         int n = nBytes;
3226         int nDone = 0;
3227         yaffs_ChunkCache *cache;
3228
3229         yaffs_Device *dev;
3230
3231         dev = in->myDev;
3232
3233         while (n > 0) {
3234                 chunk = offset / dev->nBytesPerChunk + 1;   /* The first chunk is 1 */
3235                 start = offset % dev->nBytesPerChunk;
3236
3237                 /* OK now check for the curveball where the start and end are in
3238                  * the same chunk.
3239                  */
3240                 if ((start + n) < dev->nBytesPerChunk) {
3241                         nToCopy = n;
3242                 } else {
3243                         nToCopy = dev->nBytesPerChunk - start;
3244                 }
3245
3246                 cache = yaffs_FindChunkCache(in, chunk);
3247
3248                 /* If the chunk is already in the cache or it is less than a whole chunk
3249                  * then use the cache (if there is caching)
3250                  * else bypass the cache.
3251                  */
3252                 if (cache || nToCopy != dev->nBytesPerChunk) {
3253                         if (dev->nShortOpCaches > 0) {
3254
3255                                 /* If we can't find the data in the cache, then load it up. */
3256
3257                                 if (!cache) {
3258                                         cache = yaffs_GrabChunkCache(in->myDev);
3259                                         cache->object = in;
3260                                         cache->chunkId = chunk;
3261                                         cache->dirty = 0;
3262                                         cache->locked = 0;
3263                                         yaffs_ReadChunkDataFromObject(in, chunk,
3264                                                                       cache->
3265                                                                       data);
3266                                         cache->nBytes = 0;
3267                                 }
3268
3269                                 yaffs_UseChunkCache(dev, cache, 0);
3270
3271                                 cache->locked = 1;
3272
3273 #ifdef CONFIG_YAFFS_WINCE
3274                                 yfsd_UnlockYAFFS(TRUE);
3275 #endif
3276                                 memcpy(buffer, &cache->data[start], nToCopy);
3277
3278 #ifdef CONFIG_YAFFS_WINCE
3279                                 yfsd_LockYAFFS(TRUE);
3280 #endif
3281                                 cache->locked = 0;
3282                         } else {
3283                                 /* Read into the local buffer then copy..*/
3284
3285                                 __u8 *localBuffer =
3286                                     yaffs_GetTempBuffer(dev, __LINE__);
3287                                 yaffs_ReadChunkDataFromObject(in, chunk,
3288                                                               localBuffer);
3289 #ifdef CONFIG_YAFFS_WINCE
3290                                 yfsd_UnlockYAFFS(TRUE);
3291 #endif
3292                                 memcpy(buffer, &localBuffer[start], nToCopy);
3293
3294 #ifdef CONFIG_YAFFS_WINCE
3295                                 yfsd_LockYAFFS(TRUE);
3296 #endif
3297                                 yaffs_ReleaseTempBuffer(dev, localBuffer,
3298                                                         __LINE__);
3299                         }
3300
3301                 } else {
3302 #ifdef CONFIG_YAFFS_WINCE
3303                         __u8 *localBuffer = yaffs_GetTempBuffer(dev, __LINE__);
3304
3305                         /* Under WinCE can't do direct transfer. Need to use a local buffer.
3306                          * This is because we otherwise screw up WinCE's memory mapper
3307                          */
3308                         yaffs_ReadChunkDataFromObject(in, chunk, localBuffer);
3309
3310 #ifdef CONFIG_YAFFS_WINCE
3311                         yfsd_UnlockYAFFS(TRUE);
3312 #endif
3313                         memcpy(buffer, localBuffer, dev->nBytesPerChunk);
3314
3315 #ifdef CONFIG_YAFFS_WINCE
3316                         yfsd_LockYAFFS(TRUE);
3317                         yaffs_ReleaseTempBuffer(dev, localBuffer, __LINE__);
3318 #endif
3319
3320 #else
3321                         /* A full chunk. Read directly into the supplied buffer. */
3322                         yaffs_ReadChunkDataFromObject(in, chunk, buffer);
3323 #endif
3324                 }
3325
3326                 n -= nToCopy;
3327                 offset += nToCopy;
3328                 buffer += nToCopy;
3329                 nDone += nToCopy;
3330
3331         }
3332
3333         return nDone;
3334 }
3335
3336 int yaffs_WriteDataToFile(yaffs_Object * in, const __u8 * buffer, __u32 offset,
3337                           int nBytes, int writeThrough)
3338 {
3339
3340         int chunk;
3341         int start;
3342         int nToCopy;
3343         int n = nBytes;
3344         int nDone = 0;
3345         int nToWriteBack;
3346         int startOfWrite = offset;
3347         int chunkWritten = 0;
3348         int nBytesRead;
3349
3350         yaffs_Device *dev;
3351
3352         dev = in->myDev;
3353
3354         while (n > 0 && chunkWritten >= 0) {
3355                 chunk = offset / dev->nBytesPerChunk + 1;
3356                 start = offset % dev->nBytesPerChunk;
3357
3358                 /* OK now check for the curveball where the start and end are in
3359                  * the same chunk.
3360                  */
3361
3362                 if ((start + n) < dev->nBytesPerChunk) {
3363                         nToCopy = n;
3364
3365                         /* Now folks, to calculate how many bytes to write back....
3366                          * If we're overwriting and not writing to then end of file then
3367                          * we need to write back as much as was there before.
3368                          */
3369
3370                         nBytesRead =
3371                             in->variant.fileVariant.fileSize -
3372                             ((chunk - 1) * dev->nBytesPerChunk);
3373
3374                         if (nBytesRead > dev->nBytesPerChunk) {
3375                                 nBytesRead = dev->nBytesPerChunk;
3376                         }
3377
3378                         nToWriteBack =
3379                             (nBytesRead >
3380                              (start + n)) ? nBytesRead : (start + n);
3381
3382                 } else {
3383                         nToCopy = dev->nBytesPerChunk - start;
3384                         nToWriteBack = dev->nBytesPerChunk;
3385                 }
3386
3387                 if (nToCopy != dev->nBytesPerChunk) {
3388                         /* An incomplete start or end chunk (or maybe both start and end chunk) */
3389                         if (dev->nShortOpCaches > 0) {
3390                                 yaffs_ChunkCache *cache;
3391                                 /* If we can't find the data in the cache, then load the cache */
3392                                 cache = yaffs_FindChunkCache(in, chunk);
3393                                 if (!cache
3394                                     && yaffs_CheckSpaceForAllocation(in->
3395                                                                      myDev)) {
3396                                         cache = yaffs_GrabChunkCache(in->myDev);
3397                                         cache->object = in;
3398                                         cache->chunkId = chunk;
3399                                         cache->dirty = 0;
3400                                         cache->locked = 0;
3401                                         yaffs_ReadChunkDataFromObject(in, chunk,
3402                                                                       cache->
3403                                                                       data);
3404                                 }
3405
3406                                 if (cache) {
3407                                         yaffs_UseChunkCache(dev, cache, 1);
3408                                         cache->locked = 1;
3409 #ifdef CONFIG_YAFFS_WINCE
3410                                         yfsd_UnlockYAFFS(TRUE);
3411 #endif
3412
3413                                         memcpy(&cache->data[start], buffer,
3414                                                nToCopy);
3415
3416 #ifdef CONFIG_YAFFS_WINCE
3417                                         yfsd_LockYAFFS(TRUE);
3418 #endif
3419                                         cache->locked = 0;
3420                                         cache->nBytes = nToWriteBack;
3421
3422                                         if (writeThrough) {
3423                                                 chunkWritten =
3424                                                     yaffs_WriteChunkDataToObject
3425                                                     (cache->object,
3426                                                      cache->chunkId,
3427                                                      cache->data, cache->nBytes,
3428                                                      1);
3429                                                 cache->dirty = 0;
3430                                         }
3431
3432                                 } else {
3433                                         chunkWritten = -1;      /* fail the write */
3434                                 }
3435                         } else {
3436                                 /* An incomplete start or end chunk (or maybe both start and end chunk)
3437                                  * Read into the local buffer then copy, then copy over and write back.
3438                                  */
3439
3440                                 __u8 *localBuffer =
3441                                     yaffs_GetTempBuffer(dev, __LINE__);
3442
3443                                 yaffs_ReadChunkDataFromObject(in, chunk,
3444                                                               localBuffer);
3445
3446 #ifdef CONFIG_YAFFS_WINCE
3447                                 yfsd_UnlockYAFFS(TRUE);
3448 #endif
3449
3450                                 memcpy(&localBuffer[start], buffer, nToCopy);
3451
3452 #ifdef CONFIG_YAFFS_WINCE
3453                                 yfsd_LockYAFFS(TRUE);
3454 #endif
3455                                 chunkWritten =
3456                                     yaffs_WriteChunkDataToObject(in, chunk,
3457                                                                  localBuffer,
3458                                                                  nToWriteBack,
3459                                                                  0);
3460
3461                                 yaffs_ReleaseTempBuffer(dev, localBuffer,
3462                                                         __LINE__);
3463
3464                         }
3465
3466                 } else {
3467
3468 #ifdef CONFIG_YAFFS_WINCE
3469                         /* Under WinCE can't do direct transfer. Need to use a local buffer.
3470                          * This is because we otherwise screw up WinCE's memory mapper
3471                          */
3472                         __u8 *localBuffer = yaffs_GetTempBuffer(dev, __LINE__);
3473 #ifdef CONFIG_YAFFS_WINCE
3474                         yfsd_UnlockYAFFS(TRUE);
3475 #endif
3476                         memcpy(localBuffer, buffer, dev->nBytesPerChunk);
3477 #ifdef CONFIG_YAFFS_WINCE
3478                         yfsd_LockYAFFS(TRUE);
3479 #endif
3480                         chunkWritten =
3481                             yaffs_WriteChunkDataToObject(in, chunk, localBuffer,
3482                                                          dev->nBytesPerChunk,
3483                                                          0);
3484                         yaffs_ReleaseTempBuffer(dev, localBuffer, __LINE__);
3485 #else
3486                         /* A full chunk. Write directly from the supplied buffer. */
3487                         chunkWritten =
3488                             yaffs_WriteChunkDataToObject(in, chunk, buffer,
3489                                                          dev->nBytesPerChunk,
3490                                                          0);
3491 #endif
3492                         /* Since we've overwritten the cached data, we better invalidate it. */
3493                         yaffs_InvalidateChunkCache(in, chunk);
3494                 }
3495
3496                 if (chunkWritten >= 0) {
3497                         n -= nToCopy;
3498                         offset += nToCopy;
3499                         buffer += nToCopy;
3500                         nDone += nToCopy;
3501                 }
3502
3503         }
3504
3505         /* Update file object */
3506
3507         if ((startOfWrite + nDone) > in->variant.fileVariant.fileSize) {
3508                 in->variant.fileVariant.fileSize = (startOfWrite + nDone);
3509         }
3510
3511         in->dirty = 1;
3512
3513         return nDone;
3514 }
3515
3516
3517 /* ---------------------- File resizing stuff ------------------ */
3518
3519 static void yaffs_PruneResizedChunks(yaffs_Object * in, int newSize)
3520 {
3521
3522         yaffs_Device *dev = in->myDev;
3523         int oldFileSize = in->variant.fileVariant.fileSize;
3524
3525         int lastDel = 1 + (oldFileSize - 1) / dev->nBytesPerChunk;
3526
3527         int startDel = 1 + (newSize + dev->nBytesPerChunk - 1) /
3528             dev->nBytesPerChunk;
3529         int i;
3530         int chunkId;
3531
3532         /* Delete backwards so that we don't end up with holes if
3533          * power is lost part-way through the operation.
3534          */
3535         for (i = lastDel; i >= startDel; i--) {
3536                 /* NB this could be optimised somewhat,
3537                  * eg. could retrieve the tags and write them without
3538                  * using yaffs_DeleteChunk
3539                  */
3540
3541                 chunkId = yaffs_FindAndDeleteChunkInFile(in, i, NULL);
3542                 if (chunkId > 0) {
3543                         if (chunkId <
3544                             (dev->internalStartBlock * dev->nChunksPerBlock)
3545                             || chunkId >=
3546                             ((dev->internalEndBlock +
3547                               1) * dev->nChunksPerBlock)) {
3548                                 T(YAFFS_TRACE_ALWAYS,
3549                                   (TSTR("Found daft chunkId %d for %d" TENDSTR),
3550                                    chunkId, i));
3551                         } else {
3552                                 in->nDataChunks--;
3553                                 yaffs_DeleteChunk(dev, chunkId, 1, __LINE__);
3554                         }
3555                 }
3556         }
3557
3558 }
3559
3560 int yaffs_ResizeFile(yaffs_Object * in, int newSize)
3561 {
3562
3563         int oldFileSize = in->variant.fileVariant.fileSize;
3564         int sizeOfPartialChunk;
3565         yaffs_Device *dev = in->myDev;
3566
3567         sizeOfPartialChunk = newSize % dev->nBytesPerChunk;
3568
3569         yaffs_FlushFilesChunkCache(in);
3570         yaffs_InvalidateWholeChunkCache(in);
3571
3572         yaffs_CheckGarbageCollection(dev);
3573
3574         if (in->variantType != YAFFS_OBJECT_TYPE_FILE) {
3575                 return yaffs_GetFileSize(in);
3576         }
3577
3578         if (newSize == oldFileSize) {
3579                 return oldFileSize;
3580         }
3581
3582         if (newSize < oldFileSize) {
3583
3584                 yaffs_PruneResizedChunks(in, newSize);
3585
3586                 if (sizeOfPartialChunk != 0) {
3587                         int lastChunk = 1 + newSize / dev->nBytesPerChunk;
3588                         __u8 *localBuffer = yaffs_GetTempBuffer(dev, __LINE__);
3589
3590                         /* Got to read and rewrite the last chunk with its new size and zero pad */
3591                         yaffs_ReadChunkDataFromObject(in, lastChunk,
3592                                                       localBuffer);
3593
3594                         memset(localBuffer + sizeOfPartialChunk, 0,
3595                                dev->nBytesPerChunk - sizeOfPartialChunk);
3596
3597                         yaffs_WriteChunkDataToObject(in, lastChunk, localBuffer,
3598                                                      sizeOfPartialChunk, 1);
3599
3600                         yaffs_ReleaseTempBuffer(dev, localBuffer, __LINE__);
3601                 }
3602
3603                 in->variant.fileVariant.fileSize = newSize;
3604
3605                 yaffs_PruneFileStructure(dev, &in->variant.fileVariant);
3606         }
3607         /* Write a new object header.
3608          * show we've shrunk the file, if need be
3609          * Do this only if the file is not in the deleted directories.
3610          */
3611         if (in->parent->objectId != YAFFS_OBJECTID_UNLINKED &&
3612             in->parent->objectId != YAFFS_OBJECTID_DELETED) {
3613                 yaffs_UpdateObjectHeader(in, NULL, 0,
3614                                          (newSize < oldFileSize) ? 1 : 0, 0);
3615         }
3616
3617         return newSize;
3618 }
3619
3620 loff_t yaffs_GetFileSize(yaffs_Object * obj)
3621 {
3622         obj = yaffs_GetEquivalentObject(obj);
3623
3624         switch (obj->variantType) {
3625         case YAFFS_OBJECT_TYPE_FILE:
3626                 return obj->variant.fileVariant.fileSize;
3627         case YAFFS_OBJECT_TYPE_SYMLINK:
3628                 return yaffs_strlen(obj->variant.symLinkVariant.alias);
3629         default:
3630                 return 0;
3631         }
3632 }
3633
3634
3635
3636 int yaffs_FlushFile(yaffs_Object * in, int updateTime)
3637 {
3638         int retVal;
3639         if (in->dirty) {
3640                 yaffs_FlushFilesChunkCache(in);
3641                 if (updateTime) {
3642 #ifdef CONFIG_YAFFS_WINCE
3643                         yfsd_WinFileTimeNow(in->win_mtime);
3644 #else
3645
3646                         in->yst_mtime = Y_CURRENT_TIME;
3647
3648 #endif
3649                 }
3650
3651                 retVal =
3652                     (yaffs_UpdateObjectHeader(in, NULL, 0, 0, 0) >=
3653                      0) ? YAFFS_OK : YAFFS_FAIL;
3654         } else {
3655                 retVal = YAFFS_OK;
3656         }
3657
3658         return retVal;
3659
3660 }
3661
3662 static int yaffs_DoGenericObjectDeletion(yaffs_Object * in)
3663 {
3664
3665         /* First off, invalidate the file's data in the cache, without flushing. */
3666         yaffs_InvalidateWholeChunkCache(in);
3667
3668         if (in->myDev->isYaffs2 && (in->parent != in->myDev->deletedDir)) {
3669                 /* Move to the unlinked directory so we have a record that it was deleted. */
3670                 yaffs_ChangeObjectName(in, in->myDev->deletedDir, NULL, 0, 0);
3671
3672         }
3673
3674         yaffs_RemoveObjectFromDirectory(in);
3675         yaffs_DeleteChunk(in->myDev, in->chunkId, 1, __LINE__);
3676         in->chunkId = -1;
3677
3678         yaffs_FreeObject(in);
3679         return YAFFS_OK;
3680
3681 }
3682
3683 /* yaffs_DeleteFile deletes the whole file data
3684  * and the inode associated with the file.
3685  * It does not delete the links associated with the file.
3686  */
3687 static int yaffs_UnlinkFile(yaffs_Object * in)
3688 {
3689
3690         int retVal;
3691         int immediateDeletion = 0;
3692
3693         if (1) {
3694 #ifdef __KERNEL__
3695                 if (!in->myInode) {
3696                         immediateDeletion = 1;
3697
3698                 }
3699 #else
3700                 if (in->inUse <= 0) {
3701                         immediateDeletion = 1;
3702
3703                 }
3704 #endif
3705                 if (immediateDeletion) {
3706                         retVal =
3707                             yaffs_ChangeObjectName(in, in->myDev->deletedDir,
3708                                                    NULL, 0, 0);
3709                         T(YAFFS_TRACE_TRACING,
3710                           (TSTR("yaffs: immediate deletion of file %d" TENDSTR),
3711                            in->objectId));
3712                         in->deleted = 1;
3713                         in->myDev->nDeletedFiles++;
3714                         if (0 && in->myDev->isYaffs2) {
3715                                 yaffs_ResizeFile(in, 0);
3716                         }
3717                         yaffs_SoftDeleteFile(in);
3718                 } else {
3719                         retVal =
3720                             yaffs_ChangeObjectName(in, in->myDev->unlinkedDir,
3721                                                    NULL, 0, 0);
3722                 }
3723
3724         }
3725         return retVal;
3726 }
3727
3728 int yaffs_DeleteFile(yaffs_Object * in)
3729 {
3730         int retVal = YAFFS_OK;
3731
3732         if (in->nDataChunks > 0) {
3733                 /* Use soft deletion if there is data in the file */
3734                 if (!in->unlinked) {
3735                         retVal = yaffs_UnlinkFile(in);
3736                 }
3737                 if (retVal == YAFFS_OK && in->unlinked && !in->deleted) {
3738                         in->deleted = 1;
3739                         in->myDev->nDeletedFiles++;
3740                         yaffs_SoftDeleteFile(in);
3741                 }
3742                 return in->deleted ? YAFFS_OK : YAFFS_FAIL;
3743         } else {
3744                 /* The file has no data chunks so we toss it immediately */
3745                 yaffs_FreeTnode(in->myDev, in->variant.fileVariant.top);
3746                 in->variant.fileVariant.top = NULL;
3747                 yaffs_DoGenericObjectDeletion(in);
3748
3749                 return YAFFS_OK;
3750         }
3751 }
3752
3753 static int yaffs_DeleteDirectory(yaffs_Object * in)
3754 {
3755         /* First check that the directory is empty. */
3756         if (list_empty(&in->variant.directoryVariant.children)) {
3757                 return yaffs_DoGenericObjectDeletion(in);
3758         }
3759
3760         return YAFFS_FAIL;
3761
3762 }
3763
3764 static int yaffs_DeleteSymLink(yaffs_Object * in)
3765 {
3766         YFREE(in->variant.symLinkVariant.alias);
3767
3768         return yaffs_DoGenericObjectDeletion(in);
3769 }
3770
3771 static int yaffs_DeleteHardLink(yaffs_Object * in)
3772 {
3773         /* remove this hardlink from the list assocaited with the equivalent
3774          * object
3775          */
3776         list_del(&in->hardLinks);
3777         return yaffs_DoGenericObjectDeletion(in);
3778 }
3779
3780 static void yaffs_DestroyObject(yaffs_Object * obj)
3781 {
3782         switch (obj->variantType) {
3783         case YAFFS_OBJECT_TYPE_FILE:
3784                 yaffs_DeleteFile(obj);
3785                 break;
3786         case YAFFS_OBJECT_TYPE_DIRECTORY:
3787                 yaffs_DeleteDirectory(obj);
3788                 break;
3789         case YAFFS_OBJECT_TYPE_SYMLINK:
3790                 yaffs_DeleteSymLink(obj);
3791                 break;
3792         case YAFFS_OBJECT_TYPE_HARDLINK:
3793                 yaffs_DeleteHardLink(obj);
3794                 break;
3795         case YAFFS_OBJECT_TYPE_SPECIAL:
3796                 yaffs_DoGenericObjectDeletion(obj);
3797                 break;
3798         case YAFFS_OBJECT_TYPE_UNKNOWN:
3799                 break;          /* should not happen. */
3800         }
3801 }
3802
3803 static int yaffs_UnlinkWorker(yaffs_Object * obj)
3804 {
3805
3806         if (obj->variantType == YAFFS_OBJECT_TYPE_HARDLINK) {
3807                 return yaffs_DeleteHardLink(obj);
3808         } else if (!list_empty(&obj->hardLinks)) {
3809                 /* Curve ball: We're unlinking an object that has a hardlink.
3810                  *
3811                  * This problem arises because we are not strictly following
3812                  * The Linux link/inode model.
3813                  *
3814                  * We can't really delete the object.
3815                  * Instead, we do the following:
3816                  * - Select a hardlink.
3817                  * - Unhook it from the hard links
3818                  * - Unhook it from its parent directory (so that the rename can work)
3819                  * - Rename the object to the hardlink's name.
3820                  * - Delete the hardlink
3821                  */
3822
3823                 yaffs_Object *hl;
3824                 int retVal;
3825                 YCHAR name[YAFFS_MAX_NAME_LENGTH + 1];
3826
3827                 hl = list_entry(obj->hardLinks.next, yaffs_Object, hardLinks);
3828
3829                 list_del_init(&hl->hardLinks);
3830                 list_del_init(&hl->siblings);
3831
3832                 yaffs_GetObjectName(hl, name, YAFFS_MAX_NAME_LENGTH + 1);
3833
3834                 retVal = yaffs_ChangeObjectName(obj, hl->parent, name, 0, 0);
3835
3836                 if (retVal == YAFFS_OK) {
3837                         retVal = yaffs_DoGenericObjectDeletion(hl);
3838                 }
3839                 return retVal;
3840
3841         } else {
3842                 switch (obj->variantType) {
3843                 case YAFFS_OBJECT_TYPE_FILE:
3844                         return yaffs_UnlinkFile(obj);
3845                         break;
3846                 case YAFFS_OBJECT_TYPE_DIRECTORY:
3847                         return yaffs_DeleteDirectory(obj);
3848                         break;
3849                 case YAFFS_OBJECT_TYPE_SYMLINK:
3850                         return yaffs_DeleteSymLink(obj);
3851                         break;
3852                 case YAFFS_OBJECT_TYPE_SPECIAL:
3853                         return yaffs_DoGenericObjectDeletion(obj);
3854                         break;
3855                 case YAFFS_OBJECT_TYPE_HARDLINK:
3856                 case YAFFS_OBJECT_TYPE_UNKNOWN:
3857                 default:
3858                         return YAFFS_FAIL;
3859                 }
3860         }
3861 }
3862
3863
3864 static int yaffs_UnlinkObject( yaffs_Object *obj)
3865 {
3866
3867         if (obj && obj->unlinkAllowed) {
3868                 return yaffs_UnlinkWorker(obj);
3869         }
3870
3871         return YAFFS_FAIL;
3872
3873 }
3874 int yaffs_Unlink(yaffs_Object * dir, const YCHAR * name)
3875 {
3876         yaffs_Object *obj;
3877
3878         obj = yaffs_FindObjectByName(dir, name);
3879         return yaffs_UnlinkObject(obj);
3880 }
3881
3882 /*----------------------- Initialisation Scanning ---------------------- */
3883
3884 static void yaffs_HandleShadowedObject(yaffs_Device * dev, int objId,
3885                                        int backwardScanning)
3886 {
3887         yaffs_Object *obj;
3888
3889         if (!backwardScanning) {
3890                 /* Handle YAFFS1 forward scanning case
3891                  * For YAFFS1 we always do the deletion
3892                  */
3893
3894         } else {
3895                 /* Handle YAFFS2 case (backward scanning)
3896                  * If the shadowed object exists then ignore.
3897                  */
3898                 if (yaffs_FindObjectByNumber(dev, objId)) {
3899                         return;
3900                 }
3901         }
3902
3903         /* Let's create it (if it does not exist) assuming it is a file so that it can do shrinking etc.
3904          * We put it in unlinked dir to be cleaned up after the scanning
3905          */
3906         obj =
3907             yaffs_FindOrCreateObjectByNumber(dev, objId,
3908                                              YAFFS_OBJECT_TYPE_FILE);
3909         yaffs_AddObjectToDirectory(dev->unlinkedDir, obj);
3910         obj->variant.fileVariant.shrinkSize = 0;
3911         obj->valid = 1;         /* So that we don't read any other info for this file */
3912
3913 }
3914
3915 typedef struct {
3916         int seq;
3917         int block;
3918 } yaffs_BlockIndex;
3919
3920 static int yaffs_Scan(yaffs_Device * dev)
3921 {
3922         yaffs_ExtendedTags tags;
3923         int blk;
3924         int blockIterator;
3925         int startIterator;
3926         int endIterator;
3927         int nBlocksToScan = 0;
3928
3929         int chunk;
3930         int c;
3931         int deleted;
3932         yaffs_BlockState state;
3933         yaffs_Object *hardList = NULL;
3934         yaffs_Object *hl;
3935         yaffs_BlockInfo *bi;
3936         int sequenceNumber;
3937         yaffs_ObjectHeader *oh;
3938         yaffs_Object *in;
3939         yaffs_Object *parent;
3940         int nBlocks = dev->internalEndBlock - dev->internalStartBlock + 1;
3941
3942         __u8 *chunkData;
3943
3944         yaffs_BlockIndex *blockIndex = NULL;
3945
3946         T(YAFFS_TRACE_SCAN,
3947           (TSTR("yaffs_Scan starts  intstartblk %d intendblk %d..." TENDSTR),
3948            dev->internalStartBlock, dev->internalEndBlock));
3949
3950         chunkData = yaffs_GetTempBuffer(dev, __LINE__);
3951
3952         dev->sequenceNumber = YAFFS_LOWEST_SEQUENCE_NUMBER;
3953
3954         if (dev->isYaffs2) {
3955                 blockIndex = YMALLOC(nBlocks * sizeof(yaffs_BlockIndex));
3956         }
3957
3958         /* Scan all the blocks to determine their state */
3959         for (blk = dev->internalStartBlock; blk <= dev->internalEndBlock; blk++) {
3960                 bi = yaffs_GetBlockInfo(dev, blk);
3961                 yaffs_ClearChunkBits(dev, blk);
3962                 bi->pagesInUse = 0;
3963                 bi->softDeletions = 0;
3964
3965                 yaffs_QueryInitialBlockState(dev, blk, &state, &sequenceNumber);
3966
3967                 bi->blockState = state;
3968                 bi->sequenceNumber = sequenceNumber;
3969
3970                 T(YAFFS_TRACE_SCAN_DEBUG,
3971                   (TSTR("Block scanning block %d state %d seq %d" TENDSTR), blk,
3972                    state, sequenceNumber));
3973
3974                 if (state == YAFFS_BLOCK_STATE_DEAD) {
3975                         T(YAFFS_TRACE_BAD_BLOCKS,
3976                           (TSTR("block %d is bad" TENDSTR), blk));
3977                 } else if (state == YAFFS_BLOCK_STATE_EMPTY) {
3978                         T(YAFFS_TRACE_SCAN_DEBUG,
3979                           (TSTR("Block empty " TENDSTR)));
3980                         dev->nErasedBlocks++;
3981                         dev->nFreeChunks += dev->nChunksPerBlock;
3982                 } else if (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING) {
3983
3984                         /* Determine the highest sequence number */
3985                         if (dev->isYaffs2 &&
3986                             sequenceNumber >= YAFFS_LOWEST_SEQUENCE_NUMBER &&
3987                             sequenceNumber < YAFFS_HIGHEST_SEQUENCE_NUMBER) {
3988
3989                                 blockIndex[nBlocksToScan].seq = sequenceNumber;
3990                                 blockIndex[nBlocksToScan].block = blk;
3991
3992                                 nBlocksToScan++;
3993
3994                                 if (sequenceNumber >= dev->sequenceNumber) {
3995                                         dev->sequenceNumber = sequenceNumber;
3996                                 }
3997                         } else if (dev->isYaffs2) {
3998                                 /* TODO: Nasty sequence number! */
3999                                 T(YAFFS_TRACE_SCAN,
4000                                   (TSTR
4001                                    ("Block scanning block %d has bad sequence number %d"
4002                                     TENDSTR), blk, sequenceNumber));
4003
4004                         }
4005                 }
4006         }
4007
4008         /* Sort the blocks
4009          * Dungy old bubble sort for now...
4010          */
4011         if (dev->isYaffs2) {
4012                 yaffs_BlockIndex temp;
4013                 int i;
4014                 int j;
4015
4016                 for (i = 0; i < nBlocksToScan; i++)
4017                         for (j = i + 1; j < nBlocksToScan; j++)
4018                                 if (blockIndex[i].seq > blockIndex[j].seq) {
4019                                         temp = blockIndex[j];
4020                                         blockIndex[j] = blockIndex[i];
4021                                         blockIndex[i] = temp;
4022                                 }
4023         }
4024
4025         /* Now scan the blocks looking at the data. */
4026         if (dev->isYaffs2) {
4027                 startIterator = 0;
4028                 endIterator = nBlocksToScan - 1;
4029                 T(YAFFS_TRACE_SCAN_DEBUG,
4030                   (TSTR("%d blocks to be scanned" TENDSTR), nBlocksToScan));
4031         } else {
4032                 startIterator = dev->internalStartBlock;
4033                 endIterator = dev->internalEndBlock;
4034         }
4035
4036         /* For each block.... */
4037         for (blockIterator = startIterator; blockIterator <= endIterator;
4038              blockIterator++) {
4039
4040                 if (dev->isYaffs2) {
4041                         /* get the block to scan in the correct order */
4042                         blk = blockIndex[blockIterator].block;
4043                 } else {
4044                         blk = blockIterator;
4045                 }
4046
4047                 bi = yaffs_GetBlockInfo(dev, blk);
4048                 state = bi->blockState;
4049
4050                 deleted = 0;
4051
4052                 /* For each chunk in each block that needs scanning....*/
4053                 for (c = 0; c < dev->nChunksPerBlock &&
4054                      state == YAFFS_BLOCK_STATE_NEEDS_SCANNING; c++) {
4055                         /* Read the tags and decide what to do */
4056                         chunk = blk * dev->nChunksPerBlock + c;
4057
4058                         yaffs_ReadChunkWithTagsFromNAND(dev, chunk, NULL,
4059                                                         &tags);
4060
4061                         /* Let's have a good look at this chunk... */
4062
4063                         if (!dev->isYaffs2 && tags.chunkDeleted) {
4064                                 /* YAFFS1 only...
4065                                  * A deleted chunk
4066                                  */
4067                                 deleted++;
4068                                 dev->nFreeChunks++;
4069                                 /*T((" %d %d deleted\n",blk,c)); */
4070                         } else if (!tags.chunkUsed) {
4071                                 /* An unassigned chunk in the block
4072                                  * This means that either the block is empty or
4073                                  * this is the one being allocated from
4074                                  */
4075
4076                                 if (c == 0) {
4077                                         /* We're looking at the first chunk in the block so the block is unused */
4078                                         state = YAFFS_BLOCK_STATE_EMPTY;
4079                                         dev->nErasedBlocks++;
4080                                 } else {
4081                                         /* this is the block being allocated from */
4082                                         T(YAFFS_TRACE_SCAN,
4083                                           (TSTR
4084                                            (" Allocating from %d %d" TENDSTR),
4085                                            blk, c));
4086                                         state = YAFFS_BLOCK_STATE_ALLOCATING;
4087                                         dev->allocationBlock = blk;
4088                                         dev->allocationPage = c;
4089                                         dev->allocationBlockFinder = blk;
4090                                         /* Set it to here to encourage the allocator to go forth from here. */
4091
4092                                         /* Yaffs2 sanity check:
4093                                          * This should be the one with the highest sequence number
4094                                          */
4095                                         if (dev->isYaffs2
4096                                             && (dev->sequenceNumber !=
4097                                                 bi->sequenceNumber)) {
4098                                                 T(YAFFS_TRACE_ALWAYS,
4099                                                   (TSTR
4100                                                    ("yaffs: Allocation block %d was not highest sequence id:"
4101                                                     " block seq = %d, dev seq = %d"
4102                                                     TENDSTR), blk,bi->sequenceNumber,dev->sequenceNumber));
4103                                         }
4104                                 }
4105
4106                                 dev->nFreeChunks += (dev->nChunksPerBlock - c);
4107                         } else if (tags.chunkId > 0) {
4108                                 /* chunkId > 0 so it is a data chunk... */
4109                                 unsigned int endpos;
4110
4111                                 yaffs_SetChunkBit(dev, blk, c);
4112                                 bi->pagesInUse++;
4113
4114                                 in = yaffs_FindOrCreateObjectByNumber(dev,
4115                                                                       tags.
4116                                                                       objectId,
4117                                                                       YAFFS_OBJECT_TYPE_FILE);
4118                                 /* PutChunkIntoFile checks for a clash (two data chunks with
4119                                  * the same chunkId).
4120                                  */
4121                                 yaffs_PutChunkIntoFile(in, tags.chunkId, chunk,
4122                                                        1);
4123                                 endpos =
4124                                     (tags.chunkId - 1) * dev->nBytesPerChunk +
4125                                     tags.byteCount;
4126                                 if (in->variantType == YAFFS_OBJECT_TYPE_FILE
4127                                     && in->variant.fileVariant.scannedFileSize <
4128                                     endpos) {
4129                                         in->variant.fileVariant.
4130                                             scannedFileSize = endpos;
4131                                         if (!dev->useHeaderFileSize) {
4132                                                 in->variant.fileVariant.
4133                                                     fileSize =
4134                                                     in->variant.fileVariant.
4135                                                     scannedFileSize;
4136                                         }
4137
4138                                 }
4139                                 /* T((" %d %d data %d %d\n",blk,c,tags.objectId,tags.chunkId));   */
4140                         } else {
4141                                 /* chunkId == 0, so it is an ObjectHeader.
4142                                  * Thus, we read in the object header and make the object
4143                                  */
4144                                 yaffs_SetChunkBit(dev, blk, c);
4145                                 bi->pagesInUse++;
4146
4147                                 yaffs_ReadChunkWithTagsFromNAND(dev, chunk,
4148                                                                 chunkData,
4149                                                                 NULL);
4150
4151                                 oh = (yaffs_ObjectHeader *) chunkData;
4152
4153                                 in = yaffs_FindObjectByNumber(dev,
4154                                                               tags.objectId);
4155                                 if (in && in->variantType != oh->type) {
4156                                         /* This should not happen, but somehow
4157                                          * Wev'e ended up with an objectId that has been reused but not yet
4158                                          * deleted, and worse still it has changed type. Delete the old object.
4159                                          */
4160
4161                                         yaffs_DestroyObject(in);
4162
4163                                         in = 0;
4164                                 }
4165
4166                                 in = yaffs_FindOrCreateObjectByNumber(dev,
4167                                                                       tags.
4168                                                                       objectId,
4169                                                                       oh->type);
4170
4171                                 if (oh->shadowsObject > 0) {
4172                                         yaffs_HandleShadowedObject(dev,
4173                                                                    oh->
4174                                                                    shadowsObject,
4175                                                                    0);
4176                                 }
4177
4178                                 if (in->valid) {
4179                                         /* We have already filled this one. We have a duplicate and need to resolve it. */
4180
4181                                         unsigned existingSerial = in->serial;
4182                                         unsigned newSerial = tags.serialNumber;
4183
4184                                         if (dev->isYaffs2 ||
4185                                             ((existingSerial + 1) & 3) ==
4186                                             newSerial) {
4187                                                 /* Use new one - destroy the exisiting one */
4188                                                 yaffs_DeleteChunk(dev,
4189                                                                   in->chunkId,
4190                                                                   1, __LINE__);
4191                                                 in->valid = 0;
4192                                         } else {
4193                                                 /* Use existing - destroy this one. */
4194                                                 yaffs_DeleteChunk(dev, chunk, 1,
4195                                                                   __LINE__);
4196                                         }
4197                                 }
4198
4199                                 if (!in->valid &&
4200                                     (tags.objectId == YAFFS_OBJECTID_ROOT ||
4201                                      tags.objectId == YAFFS_OBJECTID_LOSTNFOUND)) {
4202                                         /* We only load some info, don't fiddle with directory structure */
4203                                         in->valid = 1;
4204                                         in->variantType = oh->type;
4205
4206                                         in->yst_mode = oh->yst_mode;
4207 #ifdef CONFIG_YAFFS_WINCE
4208                                         in->win_atime[0] = oh->win_atime[0];
4209                                         in->win_ctime[0] = oh->win_ctime[0];
4210                                         in->win_mtime[0] = oh->win_mtime[0];
4211                                         in->win_atime[1] = oh->win_atime[1];
4212                                         in->win_ctime[1] = oh->win_ctime[1];
4213                                         in->win_mtime[1] = oh->win_mtime[1];
4214 #else
4215                                         in->yst_uid = oh->yst_uid;
4216                                         in->yst_gid = oh->yst_gid;
4217                                         in->yst_atime = oh->yst_atime;
4218                                         in->yst_mtime = oh->yst_mtime;
4219                                         in->yst_ctime = oh->yst_ctime;
4220                                         in->yst_rdev = oh->yst_rdev;
4221 #endif
4222                                         in->chunkId = chunk;
4223
4224                                 } else if (!in->valid) {
4225                                         /* we need to load this info */
4226
4227                                         in->valid = 1;
4228                                         in->variantType = oh->type;
4229
4230                                         in->yst_mode = oh->yst_mode;
4231 #ifdef CONFIG_YAFFS_WINCE
4232                                         in->win_atime[0] = oh->win_atime[0];
4233                                         in->win_ctime[0] = oh->win_ctime[0];
4234                                         in->win_mtime[0] = oh->win_mtime[0];
4235                                         in->win_atime[1] = oh->win_atime[1];
4236                                         in->win_ctime[1] = oh->win_ctime[1];
4237                                         in->win_mtime[1] = oh->win_mtime[1];
4238 #else
4239                                         in->yst_uid = oh->yst_uid;
4240                                         in->yst_gid = oh->yst_gid;
4241                                         in->yst_atime = oh->yst_atime;
4242                                         in->yst_mtime = oh->yst_mtime;
4243                                         in->yst_ctime = oh->yst_ctime;
4244                                         in->yst_rdev = oh->yst_rdev;
4245 #endif
4246                                         in->chunkId = chunk;
4247
4248                                         yaffs_SetObjectName(in, oh->name);
4249                                         in->dirty = 0;
4250
4251                                         /* directory stuff...
4252                                          * hook up to parent
4253                                          */
4254
4255                                         parent =
4256                                             yaffs_FindOrCreateObjectByNumber
4257                                             (dev, oh->parentObjectId,
4258                                              YAFFS_OBJECT_TYPE_DIRECTORY);
4259                                         if (parent->variantType ==
4260                                             YAFFS_OBJECT_TYPE_UNKNOWN) {
4261                                                 /* Set up as a directory */
4262                                                 parent->variantType =
4263                                                     YAFFS_OBJECT_TYPE_DIRECTORY;
4264                                                 INIT_LIST_HEAD(&parent->variant.
4265                                                                directoryVariant.
4266                                                                children);
4267                                         } else if (parent->variantType !=
4268                                                    YAFFS_OBJECT_TYPE_DIRECTORY)
4269                                         {
4270                                                 /* Hoosterman, another problem....
4271                                                  * We're trying to use a non-directory as a directory
4272                                                  */
4273
4274                                                 T(YAFFS_TRACE_ERROR,
4275                                                   (TSTR
4276                                                    ("yaffs tragedy: attempting to use non-directory as"
4277                                                     " a directory in scan. Put in lost+found."
4278                                                     TENDSTR)));
4279                                                 parent = dev->lostNFoundDir;
4280                                         }
4281
4282                                         yaffs_AddObjectToDirectory(parent, in);
4283
4284                                         if (0 && (parent == dev->deletedDir ||
4285                                                   parent == dev->unlinkedDir)) {
4286                                                 in->deleted = 1;        /* If it is unlinked at start up then it wants deleting */
4287                                                 dev->nDeletedFiles++;
4288                                         }
4289                                         /* Note re hardlinks.
4290                                          * Since we might scan a hardlink before its equivalent object is scanned
4291                                          * we put them all in a list.
4292                                          * After scanning is complete, we should have all the objects, so we run through this
4293                                          * list and fix up all the chains.
4294                                          */
4295
4296                                         switch (in->variantType) {
4297                                         case YAFFS_OBJECT_TYPE_UNKNOWN:
4298                                                 /* Todo got a problem */
4299                                                 break;
4300                                         case YAFFS_OBJECT_TYPE_FILE:
4301                                                 if (dev->isYaffs2
4302                                                     && oh->isShrink) {
4303                                                         /* Prune back the shrunken chunks */
4304                                                         yaffs_PruneResizedChunks
4305                                                             (in, oh->fileSize);
4306                                                         /* Mark the block as having a shrinkHeader */
4307                                                         bi->hasShrinkHeader = 1;
4308                                                 }
4309
4310                                                 if (dev->useHeaderFileSize)
4311
4312                                                         in->variant.fileVariant.
4313                                                             fileSize =
4314                                                             oh->fileSize;
4315
4316                                                 break;
4317                                         case YAFFS_OBJECT_TYPE_HARDLINK:
4318                                                 in->variant.hardLinkVariant.
4319                                                     equivalentObjectId =
4320                                                     oh->equivalentObjectId;
4321                                                 in->hardLinks.next =
4322                                                     (struct list_head *)
4323                                                     hardList;
4324                                                 hardList = in;
4325                                                 break;
4326                                         case YAFFS_OBJECT_TYPE_DIRECTORY:
4327                                                 /* Do nothing */
4328                                                 break;
4329                                         case YAFFS_OBJECT_TYPE_SPECIAL:
4330                                                 /* Do nothing */
4331                                                 break;
4332                                         case YAFFS_OBJECT_TYPE_SYMLINK:
4333                                                 in->variant.symLinkVariant.
4334                                                     alias =
4335                                                     yaffs_CloneString(oh->alias);
4336                                                 break;
4337                                         }
4338
4339                                         if (parent == dev->deletedDir) {
4340                                                 yaffs_DestroyObject(in);
4341                                                 bi->hasShrinkHeader = 1;
4342                                         }
4343                                 }
4344                         }
4345                 }
4346
4347                 if (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING) {
4348                         /* If we got this far while scanning, then the block is fully allocated.*/
4349                         state = YAFFS_BLOCK_STATE_FULL;
4350                 }
4351
4352                 bi->blockState = state;
4353
4354                 /* Now let's see if it was dirty */
4355                 if (bi->pagesInUse == 0 &&
4356                     !bi->hasShrinkHeader &&
4357                     bi->blockState == YAFFS_BLOCK_STATE_FULL) {
4358                         yaffs_BlockBecameDirty(dev, blk);
4359                 }
4360
4361         }
4362
4363         if (blockIndex) {
4364                 YFREE(blockIndex);
4365         }
4366
4367         /* Ok, we've done all the scanning.
4368          * Fix up the hard link chains.
4369          * We should now have scanned all the objects, now it's time to add these
4370          * hardlinks.
4371          */
4372         while (hardList) {
4373                 hl = hardList;
4374                 hardList = (yaffs_Object *) (hardList->hardLinks.next);
4375
4376                 in = yaffs_FindObjectByNumber(dev,
4377                                               hl->variant.hardLinkVariant.
4378                                               equivalentObjectId);
4379
4380                 if (in) {
4381                         /* Add the hardlink pointers */
4382                         hl->variant.hardLinkVariant.equivalentObject = in;
4383                         list_add(&hl->hardLinks, &in->hardLinks);
4384                 } else {
4385                         /* Todo Need to report/handle this better.
4386                          * Got a problem... hardlink to a non-existant object
4387                          */
4388                         hl->variant.hardLinkVariant.equivalentObject = NULL;
4389                         INIT_LIST_HEAD(&hl->hardLinks);
4390
4391                 }
4392
4393         }
4394
4395         /* Handle the unlinked files. Since they were left in an unlinked state we should
4396          * just delete them.
4397          */
4398         {
4399                 struct list_head *i;
4400                 struct list_head *n;
4401
4402                 yaffs_Object *l;
4403                 /* Soft delete all the unlinked files */
4404                 list_for_each_safe(i, n,
4405                                    &dev->unlinkedDir->variant.directoryVariant.
4406                                    children) {
4407                         if (i) {
4408                                 l = list_entry(i, yaffs_Object, siblings);
4409                                 yaffs_DestroyObject(l);
4410                         }
4411                 }
4412         }
4413
4414         yaffs_ReleaseTempBuffer(dev, chunkData, __LINE__);
4415
4416         T(YAFFS_TRACE_SCAN, (TSTR("yaffs_Scan ends" TENDSTR)));
4417
4418         return YAFFS_OK;
4419 }
4420
4421 static void yaffs_CheckObjectDetailsLoaded(yaffs_Object *in)
4422 {
4423         __u8 *chunkData;
4424         yaffs_ObjectHeader *oh;
4425         yaffs_Device *dev = in->myDev;
4426
4427         if(in->lazyLoaded){
4428                 in->lazyLoaded = 0;
4429                 chunkData = yaffs_GetTempBuffer(dev, __LINE__);
4430
4431                 yaffs_ReadChunkWithTagsFromNAND(dev,in->chunkId,chunkData,NULL);
4432                 oh = (yaffs_ObjectHeader *) chunkData;
4433
4434                 in->yst_mode = oh->yst_mode;
4435 #ifdef CONFIG_YAFFS_WINCE
4436                 in->win_atime[0] = oh->win_atime[0];
4437                 in->win_ctime[0] = oh->win_ctime[0];
4438                 in->win_mtime[0] = oh->win_mtime[0];
4439                 in->win_atime[1] = oh->win_atime[1];
4440                 in->win_ctime[1] = oh->win_ctime[1];
4441                 in->win_mtime[1] = oh->win_mtime[1];
4442 #else
4443                 in->yst_uid = oh->yst_uid;
4444                 in->yst_gid = oh->yst_gid;
4445                 in->yst_atime = oh->yst_atime;
4446                 in->yst_mtime = oh->yst_mtime;
4447                 in->yst_ctime = oh->yst_ctime;
4448                 in->yst_rdev = oh->yst_rdev;
4449
4450 #endif
4451                 yaffs_SetObjectName(in, oh->name);
4452
4453                 if(in->variantType == YAFFS_OBJECT_TYPE_SYMLINK)
4454                          in->variant.symLinkVariant.alias =
4455                                                     yaffs_CloneString(oh->alias);
4456
4457                 yaffs_ReleaseTempBuffer(dev,chunkData, __LINE__);
4458         }
4459 }
4460
4461 static int yaffs_ScanBackwards(yaffs_Device * dev)
4462 {
4463         yaffs_ExtendedTags tags;
4464         int blk;
4465         int blockIterator;
4466         int startIterator;
4467         int endIterator;
4468         int nBlocksToScan = 0;
4469
4470         int chunk;
4471         int c;
4472         int deleted;
4473         yaffs_BlockState state;
4474         yaffs_Object *hardList = NULL;
4475         yaffs_Object *hl;
4476         yaffs_BlockInfo *bi;
4477         int sequenceNumber;
4478         yaffs_ObjectHeader *oh;
4479         yaffs_Object *in;
4480         yaffs_Object *parent;
4481         int nBlocks = dev->internalEndBlock - dev->internalStartBlock + 1;
4482         int itsUnlinked;
4483         __u8 *chunkData;
4484
4485         int fileSize;
4486         int isShrink;
4487         int equivalentObjectId;
4488
4489
4490         yaffs_BlockIndex *blockIndex = NULL;
4491
4492         if (!dev->isYaffs2) {
4493                 T(YAFFS_TRACE_SCAN,
4494                   (TSTR("yaffs_ScanBackwards is only for YAFFS2!" TENDSTR)));
4495                 return YAFFS_FAIL;
4496         }
4497
4498         T(YAFFS_TRACE_SCAN,
4499           (TSTR
4500            ("yaffs_ScanBackwards starts  intstartblk %d intendblk %d..."
4501             TENDSTR), dev->internalStartBlock, dev->internalEndBlock));
4502
4503         chunkData = yaffs_GetTempBuffer(dev, __LINE__);
4504
4505         dev->sequenceNumber = YAFFS_LOWEST_SEQUENCE_NUMBER;
4506
4507         blockIndex = YMALLOC(nBlocks * sizeof(yaffs_BlockIndex));
4508
4509         /* Scan all the blocks to determine their state */
4510         for (blk = dev->internalStartBlock; blk <= dev->internalEndBlock; blk++) {
4511                 bi = yaffs_GetBlockInfo(dev, blk);
4512                 yaffs_ClearChunkBits(dev, blk);
4513                 bi->pagesInUse = 0;
4514                 bi->softDeletions = 0;
4515
4516                 yaffs_QueryInitialBlockState(dev, blk, &state, &sequenceNumber);
4517
4518                 bi->blockState = state;
4519                 bi->sequenceNumber = sequenceNumber;
4520
4521                 T(YAFFS_TRACE_SCAN_DEBUG,
4522                   (TSTR("Block scanning block %d state %d seq %d" TENDSTR), blk,
4523                    state, sequenceNumber));
4524
4525                 if (state == YAFFS_BLOCK_STATE_DEAD) {
4526                         T(YAFFS_TRACE_BAD_BLOCKS,
4527                           (TSTR("block %d is bad" TENDSTR), blk));
4528                 } else if (state == YAFFS_BLOCK_STATE_EMPTY) {
4529                         T(YAFFS_TRACE_SCAN_DEBUG,
4530                           (TSTR("Block empty " TENDSTR)));
4531                         dev->nErasedBlocks++;
4532                         dev->nFreeChunks += dev->nChunksPerBlock;
4533                 } else if (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING) {
4534
4535                         /* Determine the highest sequence number */
4536                         if (dev->isYaffs2 &&
4537                             sequenceNumber >= YAFFS_LOWEST_SEQUENCE_NUMBER &&
4538                             sequenceNumber < YAFFS_HIGHEST_SEQUENCE_NUMBER) {
4539
4540                                 blockIndex[nBlocksToScan].seq = sequenceNumber;
4541                                 blockIndex[nBlocksToScan].block = blk;
4542
4543                                 nBlocksToScan++;
4544
4545                                 if (sequenceNumber >= dev->sequenceNumber) {
4546                                         dev->sequenceNumber = sequenceNumber;
4547                                 }
4548                         } else if (dev->isYaffs2) {
4549                                 /* TODO: Nasty sequence number! */
4550                                 T(YAFFS_TRACE_SCAN,
4551                                   (TSTR
4552                                    ("Block scanning block %d has bad sequence number %d"
4553                                     TENDSTR), blk, sequenceNumber));
4554
4555                         }
4556                 }
4557         }
4558
4559         /*
4560          * Sort the blocks
4561          * Dungy old bubble sort for now...
4562          */
4563         {
4564                 yaffs_BlockIndex temp;
4565                 int i;
4566                 int j;
4567
4568                 for (i = 0; i < nBlocksToScan; i++)
4569                         for (j = i + 1; j < nBlocksToScan; j++)
4570                                 if (blockIndex[i].seq > blockIndex[j].seq) {
4571                                         temp = blockIndex[j];
4572                                         blockIndex[j] = blockIndex[i];
4573                                         blockIndex[i] = temp;
4574                                 }
4575         }
4576
4577         /* Now scan the blocks looking at the data. */
4578         startIterator = 0;
4579         endIterator = nBlocksToScan - 1;
4580         T(YAFFS_TRACE_SCAN_DEBUG,
4581           (TSTR("%d blocks to be scanned" TENDSTR), nBlocksToScan));
4582
4583         /* For each block.... backwards */
4584         for (blockIterator = endIterator; blockIterator >= startIterator;
4585              blockIterator--) {
4586
4587                 /* get the block to scan in the correct order */
4588                 blk = blockIndex[blockIterator].block;
4589
4590                 bi = yaffs_GetBlockInfo(dev, blk);
4591                 state = bi->blockState;
4592
4593                 deleted = 0;
4594
4595                 /* For each chunk in each block that needs scanning.... */
4596                 for (c = dev->nChunksPerBlock - 1; c >= 0 &&
4597                      (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING ||
4598                       state == YAFFS_BLOCK_STATE_ALLOCATING); c--) {
4599                         /* Scan backwards...
4600                          * Read the tags and decide what to do
4601                          */
4602                         chunk = blk * dev->nChunksPerBlock + c;
4603
4604                         yaffs_ReadChunkWithTagsFromNAND(dev, chunk, NULL,
4605                                                         &tags);
4606
4607                         /* Let's have a good look at this chunk... */
4608
4609                         if (!tags.chunkUsed) {
4610                                 // An unassigned chunk in the block
4611                                 // This means that either the block is empty or
4612                                 // this is the one being allocated from
4613
4614                                 if (c == 0) {
4615                                         /* We're looking at the first chunk in the block so the block is unused */
4616                                         state = YAFFS_BLOCK_STATE_EMPTY;
4617                                         dev->nErasedBlocks++;
4618                                 } else {
4619                                         /* this is the block being allocated from */
4620                                         if (state ==
4621                                             YAFFS_BLOCK_STATE_NEEDS_SCANNING) {
4622                                                 T(YAFFS_TRACE_SCAN,
4623                                                   (TSTR
4624                                                    (" Allocating from %d %d"
4625                                                     TENDSTR), blk, c));
4626                                         }
4627                                         state = YAFFS_BLOCK_STATE_ALLOCATING;
4628                                         dev->allocationBlock = blk;
4629                                         dev->allocationPage = c;
4630                                         dev->allocationBlockFinder = blk;
4631                                         /* Set it to here to encourage the allocator to
4632                                          *  go forth from here.
4633                                          */
4634
4635                                         /* Yaffs2 sanity check:
4636                                          * This should be the one with the highest sequence number
4637                                          */
4638                                         if (dev->isYaffs2
4639                                             && (dev->sequenceNumber !=
4640                                                 bi->sequenceNumber)) {
4641                                                 T(YAFFS_TRACE_ALWAYS,
4642                                                   (TSTR
4643                                                    ("yaffs: Allocation block %d was not highest sequence "
4644                                                     "id: block seq = %d, dev seq = %d"
4645                                                     TENDSTR), blk,
4646                                                    bi->sequenceNumber,
4647                                                    dev->sequenceNumber));
4648                                         }
4649                                 }
4650
4651                                 dev->nFreeChunks++;
4652                         } else if (tags.chunkId > 0) {
4653                                 /* chunkId > 0 so it is a data chunk... */
4654                                 unsigned int endpos;
4655
4656                                 __u32 chunkBase =
4657                                     (tags.chunkId - 1) * dev->nBytesPerChunk;
4658
4659                                 yaffs_SetChunkBit(dev, blk, c);
4660                                 bi->pagesInUse++;
4661
4662                                 in = yaffs_FindOrCreateObjectByNumber(dev,
4663                                                                       tags.
4664                                                                       objectId,
4665                                                                       YAFFS_OBJECT_TYPE_FILE);
4666                                 if (in->variantType == YAFFS_OBJECT_TYPE_FILE
4667                                     && chunkBase <
4668                                     in->variant.fileVariant.shrinkSize) {
4669                                         /* This has not been invalidated by a resize */
4670                                         yaffs_PutChunkIntoFile(in, tags.chunkId,
4671                                                                chunk, -1);
4672
4673                                         /* File size is calculated by looking at the data chunks if we have not
4674                                          * seen an object header yet. Stop this practice once we find an object header.
4675                                          */
4676                                         endpos =
4677                                             (tags.chunkId -
4678                                              1) * dev->nBytesPerChunk +
4679                                             tags.byteCount;
4680
4681                                         if (!in->valid &&       /* have not got an object header yet */
4682                                             in->variant.fileVariant.
4683                                             scannedFileSize < endpos) {
4684                                                 in->variant.fileVariant.
4685                                                     scannedFileSize = endpos;
4686                                                 in->variant.fileVariant.
4687                                                     fileSize =
4688                                                     in->variant.fileVariant.
4689                                                     scannedFileSize;
4690                                         }
4691
4692                                 } else {
4693                                         /* This chunk has been invalidated by a resize, so delete */
4694                                         yaffs_DeleteChunk(dev, chunk, 1, __LINE__);
4695
4696                                 }
4697                         } else {
4698                                 /* chunkId == 0, so it is an ObjectHeader.
4699                                  * Thus, we read in the object header and make the object
4700                                  */
4701                                 yaffs_SetChunkBit(dev, blk, c);
4702                                 bi->pagesInUse++;
4703
4704                                 oh = NULL;
4705                                 in = NULL;
4706
4707                                 if (tags.extraHeaderInfoAvailable) {
4708                                         in = yaffs_FindOrCreateObjectByNumber
4709                                             (dev, tags.objectId,
4710                                              tags.extraObjectType);
4711                                 }
4712
4713                                 if (!in ||
4714 #ifdef CONFIG_YAFFS_DISABLE_LAZY_LOAD
4715                                     !in->valid ||
4716 #endif
4717                                     tags.extraShadows ||
4718                                     (!in->valid &&
4719                                     (tags.objectId == YAFFS_OBJECTID_ROOT ||
4720                                      tags.objectId == YAFFS_OBJECTID_LOSTNFOUND))
4721                                     ) {
4722
4723                                         /* If we don't have  valid info then we need to read the chunk
4724                                          * TODO In future we can probably defer reading the chunk and
4725                                          * living with invalid data until needed.
4726                                          */
4727
4728                                         yaffs_ReadChunkWithTagsFromNAND(dev,
4729                                                                         chunk,
4730                                                                         chunkData,
4731                                                                         NULL);
4732
4733                                         oh = (yaffs_ObjectHeader *) chunkData;
4734
4735                                         if (!in)
4736                                                 in = yaffs_FindOrCreateObjectByNumber(dev, tags.objectId, oh->type);
4737
4738                                 }
4739
4740                                 if (!in) {
4741                                         /* TODO Hoosterman we have a problem! */
4742                                         T(YAFFS_TRACE_ERROR,
4743                                           (TSTR
4744                                            ("yaffs tragedy: Could not make object for object  %d  "
4745                                             "at chunk %d during scan"
4746                                             TENDSTR), tags.objectId, chunk));
4747
4748                                 }
4749
4750                                 if (in->valid) {
4751                                         /* We have already filled this one.
4752                                          * We have a duplicate that will be discarded, but
4753                                          * we first have to suck out resize info if it is a file.
4754                                          */
4755
4756                                         if ((in->variantType == YAFFS_OBJECT_TYPE_FILE) &&
4757                                              ((oh &&
4758                                                oh-> type == YAFFS_OBJECT_TYPE_FILE)||
4759                                               (tags.extraHeaderInfoAvailable  &&
4760                                                tags.extraObjectType == YAFFS_OBJECT_TYPE_FILE))
4761                                             ) {
4762                                                 __u32 thisSize =
4763                                                     (oh) ? oh->fileSize : tags.
4764                                                     extraFileLength;
4765                                                 __u32 parentObjectId =
4766                                                     (oh) ? oh->
4767                                                     parentObjectId : tags.
4768                                                     extraParentObjectId;
4769                                                 unsigned isShrink =
4770                                                     (oh) ? oh->isShrink : tags.
4771                                                     extraIsShrinkHeader;
4772
4773                                                 /* If it is deleted (unlinked at start also means deleted)
4774                                                  * we treat the file size as being zeroed at this point.
4775                                                  */
4776                                                 if (parentObjectId ==
4777                                                     YAFFS_OBJECTID_DELETED
4778                                                     || parentObjectId ==
4779                                                     YAFFS_OBJECTID_UNLINKED) {
4780                                                         thisSize = 0;
4781                                                         isShrink = 1;
4782                                                 }
4783
4784                                                 if (isShrink &&
4785                                                     in->variant.fileVariant.
4786                                                     shrinkSize > thisSize) {
4787                                                         in->variant.fileVariant.
4788                                                             shrinkSize =
4789                                                             thisSize;
4790                                                 }
4791
4792                                                 if (isShrink) {
4793                                                         bi->hasShrinkHeader = 1;
4794                                                 }
4795
4796                                         }
4797                                         /* Use existing - destroy this one. */
4798                                         yaffs_DeleteChunk(dev, chunk, 1, __LINE__);
4799
4800                                 }
4801
4802                                 if (!in->valid &&
4803                                     (tags.objectId == YAFFS_OBJECTID_ROOT ||
4804                                      tags.objectId ==
4805                                      YAFFS_OBJECTID_LOSTNFOUND)) {
4806                                         /* We only load some info, don't fiddle with directory structure */
4807                                         in->valid = 1;
4808
4809                                         if(oh) {
4810                                                 in->variantType = oh->type;
4811
4812                                                 in->yst_mode = oh->yst_mode;
4813 #ifdef CONFIG_YAFFS_WINCE
4814                                                 in->win_atime[0] = oh->win_atime[0];
4815                                                 in->win_ctime[0] = oh->win_ctime[0];
4816                                                 in->win_mtime[0] = oh->win_mtime[0];
4817                                                 in->win_atime[1] = oh->win_atime[1];
4818                                                 in->win_ctime[1] = oh->win_ctime[1];
4819                                                 in->win_mtime[1] = oh->win_mtime[1];
4820 #else
4821                                                 in->yst_uid = oh->yst_uid;
4822                                                 in->yst_gid = oh->yst_gid;
4823                                                 in->yst_atime = oh->yst_atime;
4824                                                 in->yst_mtime = oh->yst_mtime;
4825                                                 in->yst_ctime = oh->yst_ctime;
4826                                                 in->yst_rdev = oh->yst_rdev;
4827
4828 #endif
4829                                         } else {
4830                                                 in->variantType = tags.extraObjectType;
4831                                                 in->lazyLoaded = 1;
4832                                         }
4833
4834                                         in->chunkId = chunk;
4835
4836                                 } else if (!in->valid) {
4837                                         /* we need to load this info */
4838
4839                                         in->valid = 1;
4840                                         in->chunkId = chunk;
4841
4842                                         if(oh) {
4843                                                 in->variantType = oh->type;
4844
4845                                                 in->yst_mode = oh->yst_mode;
4846 #ifdef CONFIG_YAFFS_WINCE
4847                                                 in->win_atime[0] = oh->win_atime[0];
4848                                                 in->win_ctime[0] = oh->win_ctime[0];
4849                                                 in->win_mtime[0] = oh->win_mtime[0];
4850                                                 in->win_atime[1] = oh->win_atime[1];
4851                                                 in->win_ctime[1] = oh->win_ctime[1];
4852                                                 in->win_mtime[1] = oh->win_mtime[1];
4853 #else
4854                                                 in->yst_uid = oh->yst_uid;
4855                                                 in->yst_gid = oh->yst_gid;
4856                                                 in->yst_atime = oh->yst_atime;
4857                                                 in->yst_mtime = oh->yst_mtime;
4858                                                 in->yst_ctime = oh->yst_ctime;
4859                                                 in->yst_rdev = oh->yst_rdev;
4860 #endif
4861
4862                                                 if (oh->shadowsObject > 0)
4863                                                         yaffs_HandleShadowedObject(dev,
4864                                                                            oh->
4865                                                                            shadowsObject,
4866                                                                            1);
4867
4868
4869                                                 yaffs_SetObjectName(in, oh->name);
4870                                                 parent =
4871                                                     yaffs_FindOrCreateObjectByNumber
4872                                                         (dev, oh->parentObjectId,
4873                                                          YAFFS_OBJECT_TYPE_DIRECTORY);
4874
4875                                                  fileSize = oh->fileSize;
4876                                                  isShrink = oh->isShrink;
4877                                                  equivalentObjectId = oh->equivalentObjectId;
4878
4879                                         }
4880                                         else {
4881                                                 in->variantType = tags.extraObjectType;
4882                                                 parent =
4883                                                     yaffs_FindOrCreateObjectByNumber
4884                                                         (dev, tags.extraParentObjectId,
4885                                                          YAFFS_OBJECT_TYPE_DIRECTORY);
4886                                                  fileSize = tags.extraFileLength;
4887                                                  isShrink = tags.extraIsShrinkHeader;
4888                                                  equivalentObjectId = tags.extraEquivalentObjectId;
4889                                                 in->lazyLoaded = 1;
4890
4891                                         }
4892                                         in->dirty = 0;
4893
4894                                         /* directory stuff...
4895                                          * hook up to parent
4896                                          */
4897
4898                                         if (parent->variantType ==
4899                                             YAFFS_OBJECT_TYPE_UNKNOWN) {
4900                                                 /* Set up as a directory */
4901                                                 parent->variantType =
4902                                                     YAFFS_OBJECT_TYPE_DIRECTORY;
4903                                                 INIT_LIST_HEAD(&parent->variant.
4904                                                                directoryVariant.
4905                                                                children);
4906                                         } else if (parent->variantType !=
4907                                                    YAFFS_OBJECT_TYPE_DIRECTORY)
4908                                         {
4909                                                 /* Hoosterman, another problem....
4910                                                  * We're trying to use a non-directory as a directory
4911                                                  */
4912
4913                                                 T(YAFFS_TRACE_ERROR,
4914                                                   (TSTR
4915                                                    ("yaffs tragedy: attempting to use non-directory as"
4916                                                     " a directory in scan. Put in lost+found."
4917                                                     TENDSTR)));
4918                                                 parent = dev->lostNFoundDir;
4919                                         }
4920
4921                                         yaffs_AddObjectToDirectory(parent, in);
4922
4923                                         itsUnlinked = (parent == dev->deletedDir) ||
4924                                                       (parent == dev->unlinkedDir);
4925
4926                                         if (isShrink) {
4927                                                 /* Mark the block as having a shrinkHeader */
4928                                                 bi->hasShrinkHeader = 1;
4929                                         }
4930
4931                                         /* Note re hardlinks.
4932                                          * Since we might scan a hardlink before its equivalent object is scanned
4933                                          * we put them all in a list.
4934                                          * After scanning is complete, we should have all the objects, so we run
4935                                          * through this list and fix up all the chains.
4936                                          */
4937
4938                                         switch (in->variantType) {
4939                                         case YAFFS_OBJECT_TYPE_UNKNOWN:
4940                                                 /* Todo got a problem */
4941                                                 break;
4942                                         case YAFFS_OBJECT_TYPE_FILE:
4943
4944                                                 if (in->variant.fileVariant.
4945                                                     scannedFileSize < fileSize) {
4946                                                         /* This covers the case where the file size is greater
4947                                                          * than where the data is
4948                                                          * This will happen if the file is resized to be larger
4949                                                          * than its current data extents.
4950                                                          */
4951                                                         in->variant.fileVariant.fileSize = fileSize;
4952                                                         in->variant.fileVariant.scannedFileSize =
4953                                                             in->variant.fileVariant.fileSize;
4954                                                 }
4955
4956                                                 if (isShrink &&
4957                                                     in->variant.fileVariant.shrinkSize > fileSize) {
4958                                                         in->variant.fileVariant.shrinkSize = fileSize;
4959                                                 }
4960
4961                                                 break;
4962                                         case YAFFS_OBJECT_TYPE_HARDLINK:
4963                                                 if(!itsUnlinked) {
4964                                                   in->variant.hardLinkVariant.equivalentObjectId =
4965                                                     equivalentObjectId;
4966                                                   in->hardLinks.next =
4967                                                     (struct list_head *) hardList;
4968                                                   hardList = in;
4969                                                 }
4970                                                 break;
4971                                         case YAFFS_OBJECT_TYPE_DIRECTORY:
4972                                                 /* Do nothing */
4973                                                 break;
4974                                         case YAFFS_OBJECT_TYPE_SPECIAL:
4975                                                 /* Do nothing */
4976                                                 break;
4977                                         case YAFFS_OBJECT_TYPE_SYMLINK:
4978                                                 if(oh)
4979                                                    in->variant.symLinkVariant.alias =
4980                                                     yaffs_CloneString(oh->
4981                                                                       alias);
4982                                                 break;
4983                                         }
4984
4985                                 }
4986                         }
4987                 }
4988
4989                 if (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING) {
4990                         /* If we got this far while scanning, then the block is fully allocated. */
4991                         state = YAFFS_BLOCK_STATE_FULL;
4992                 }
4993
4994                 bi->blockState = state;
4995
4996                 /* Now let's see if it was dirty */
4997                 if (bi->pagesInUse == 0 &&
4998                     !bi->hasShrinkHeader &&
4999                     bi->blockState == YAFFS_BLOCK_STATE_FULL) {
5000                         yaffs_BlockBecameDirty(dev, blk);
5001                 }
5002
5003         }
5004
5005         if (blockIndex) {
5006                 YFREE(blockIndex);
5007         }
5008         /* Ok, we've done all the scanning.
5009          * Fix up the hard link chains.
5010          * We should now have scanned all the objects, now it's time to add these
5011          * hardlinks.
5012          */
5013         while (hardList) {
5014                 hl = hardList;
5015                 hardList = (yaffs_Object *) (hardList->hardLinks.next);
5016
5017                 in = yaffs_FindObjectByNumber(dev,
5018                                               hl->variant.hardLinkVariant.
5019                                               equivalentObjectId);
5020
5021                 if (in) {
5022                         /* Add the hardlink pointers */
5023                         hl->variant.hardLinkVariant.equivalentObject = in;
5024                         list_add(&hl->hardLinks, &in->hardLinks);
5025                 } else {
5026                         /* Todo Need to report/handle this better.
5027                          * Got a problem... hardlink to a non-existant object
5028                          */
5029                         hl->variant.hardLinkVariant.equivalentObject = NULL;
5030                         INIT_LIST_HEAD(&hl->hardLinks);
5031
5032                 }
5033
5034         }
5035
5036         {
5037                 struct list_head *i;
5038                 struct list_head *n;
5039
5040                 yaffs_Object *l;
5041
5042                 /* Soft delete all the unlinked files */
5043                 list_for_each_safe(i, n,
5044                                    &dev->unlinkedDir->variant.directoryVariant.
5045                                    children) {
5046                         if (i) {
5047                                 l = list_entry(i, yaffs_Object, siblings);
5048                                 yaffs_DestroyObject(l);
5049                         }
5050                 }
5051
5052                 /* Soft delete all the deletedDir files */
5053                 list_for_each_safe(i, n,
5054                                    &dev->deletedDir->variant.directoryVariant.
5055                                    children) {
5056                         if (i) {
5057                                 l = list_entry(i, yaffs_Object, siblings);
5058                                 yaffs_DestroyObject(l);
5059
5060                         }
5061                 }
5062         }
5063
5064         yaffs_ReleaseTempBuffer(dev, chunkData, __LINE__);
5065
5066         T(YAFFS_TRACE_SCAN, (TSTR("yaffs_ScanBackwards ends" TENDSTR)));
5067
5068         return YAFFS_OK;
5069 }
5070
5071 /*------------------------------  Directory Functions ----------------------------- */
5072
5073 static void yaffs_RemoveObjectFromDirectory(yaffs_Object * obj)
5074 {
5075         yaffs_Device *dev = obj->myDev;
5076
5077         if(dev && dev->removeObjectCallback)
5078                 dev->removeObjectCallback(obj);
5079
5080         list_del_init(&obj->siblings);
5081         obj->parent = NULL;
5082 }
5083
5084
5085 static void yaffs_AddObjectToDirectory(yaffs_Object * directory,
5086                                        yaffs_Object * obj)
5087 {
5088
5089         if (!directory) {
5090                 T(YAFFS_TRACE_ALWAYS,
5091                   (TSTR
5092                    ("tragedy: Trying to add an object to a null pointer directory"
5093                     TENDSTR)));
5094                 YBUG();
5095         }
5096         if (directory->variantType != YAFFS_OBJECT_TYPE_DIRECTORY) {
5097                 T(YAFFS_TRACE_ALWAYS,
5098                   (TSTR
5099                    ("tragedy: Trying to add an object to a non-directory"
5100                     TENDSTR)));
5101                 YBUG();
5102         }
5103
5104         if (obj->siblings.prev == NULL) {
5105                 /* Not initialised */
5106                 INIT_LIST_HEAD(&obj->siblings);
5107
5108         } else if (!list_empty(&obj->siblings)) {
5109                 /* If it is holed up somewhere else, un hook it */
5110                 yaffs_RemoveObjectFromDirectory(obj);
5111         }
5112         /* Now add it */
5113         list_add(&obj->siblings, &directory->variant.directoryVariant.children);
5114         obj->parent = directory;
5115
5116         if (directory == obj->myDev->unlinkedDir
5117             || directory == obj->myDev->deletedDir) {
5118                 obj->unlinked = 1;
5119                 obj->myDev->nUnlinkedFiles++;
5120                 obj->renameAllowed = 0;
5121         }
5122 }
5123
5124 yaffs_Object *yaffs_FindObjectByName(yaffs_Object * directory,
5125                                      const YCHAR * name)
5126 {
5127         int sum;
5128
5129         struct list_head *i;
5130         YCHAR buffer[YAFFS_MAX_NAME_LENGTH + 1];
5131
5132         yaffs_Object *l;
5133
5134         if (!name) {
5135                 return NULL;
5136         }
5137
5138         if (!directory) {
5139                 T(YAFFS_TRACE_ALWAYS,
5140                   (TSTR
5141                    ("tragedy: yaffs_FindObjectByName: null pointer directory"
5142                     TENDSTR)));
5143                 YBUG();
5144         }
5145         if (directory->variantType != YAFFS_OBJECT_TYPE_DIRECTORY) {
5146                 T(YAFFS_TRACE_ALWAYS,
5147                   (TSTR
5148                    ("tragedy: yaffs_FindObjectByName: non-directory" TENDSTR)));
5149                 YBUG();
5150         }
5151
5152         sum = yaffs_CalcNameSum(name);
5153
5154         list_for_each(i, &directory->variant.directoryVariant.children) {
5155                 if (i) {
5156                         l = list_entry(i, yaffs_Object, siblings);
5157
5158                         yaffs_CheckObjectDetailsLoaded(l);
5159
5160                         /* Special case for lost-n-found */
5161                         if (l->objectId == YAFFS_OBJECTID_LOSTNFOUND) {
5162                                 if (yaffs_strcmp(name, YAFFS_LOSTNFOUND_NAME) == 0) {
5163                                         return l;
5164                                 }
5165                         } else if (yaffs_SumCompare(l->sum, sum) || l->chunkId <= 0)
5166                         {
5167                                 /* LostnFound cunk called Objxxx
5168                                  * Do a real check
5169                                  */
5170                                 yaffs_GetObjectName(l, buffer,
5171                                                     YAFFS_MAX_NAME_LENGTH);
5172                                 if (yaffs_strcmp(name, buffer) == 0) {
5173                                         return l;
5174                                 }
5175
5176                         }
5177                 }
5178         }
5179
5180         return NULL;
5181 }
5182
5183
5184 #if 0
5185 int yaffs_ApplyToDirectoryChildren(yaffs_Object * theDir,
5186                                    int (*fn) (yaffs_Object *))
5187 {
5188         struct list_head *i;
5189         yaffs_Object *l;
5190
5191         if (!theDir) {
5192                 T(YAFFS_TRACE_ALWAYS,
5193                   (TSTR
5194                    ("tragedy: yaffs_FindObjectByName: null pointer directory"
5195                     TENDSTR)));
5196                 YBUG();
5197         }
5198         if (theDir->variantType != YAFFS_OBJECT_TYPE_DIRECTORY) {
5199                 T(YAFFS_TRACE_ALWAYS,
5200                   (TSTR
5201                    ("tragedy: yaffs_FindObjectByName: non-directory" TENDSTR)));
5202                 YBUG();
5203         }
5204
5205         list_for_each(i, &theDir->variant.directoryVariant.children) {
5206                 if (i) {
5207                         l = list_entry(i, yaffs_Object, siblings);
5208                         if (l && !fn(l)) {
5209                                 return YAFFS_FAIL;
5210                         }
5211                 }
5212         }
5213
5214         return YAFFS_OK;
5215
5216 }
5217 #endif
5218
5219 /* GetEquivalentObject dereferences any hard links to get to the
5220  * actual object.
5221  */
5222
5223 yaffs_Object *yaffs_GetEquivalentObject(yaffs_Object * obj)
5224 {
5225         if (obj && obj->variantType == YAFFS_OBJECT_TYPE_HARDLINK) {
5226                 /* We want the object id of the equivalent object, not this one */
5227                 obj = obj->variant.hardLinkVariant.equivalentObject;
5228         }
5229         return obj;
5230
5231 }
5232
5233 int yaffs_GetObjectName(yaffs_Object * obj, YCHAR * name, int buffSize)
5234 {
5235         memset(name, 0, buffSize * sizeof(YCHAR));
5236
5237         yaffs_CheckObjectDetailsLoaded(obj);
5238
5239         if (obj->objectId == YAFFS_OBJECTID_LOSTNFOUND) {
5240                 yaffs_strncpy(name, YAFFS_LOSTNFOUND_NAME, buffSize - 1);
5241         } else if (obj->chunkId <= 0) {
5242                 YCHAR locName[20];
5243                 /* make up a name */
5244                 yaffs_sprintf(locName, _Y("%s%d"), YAFFS_LOSTNFOUND_PREFIX,
5245                               obj->objectId);
5246                 yaffs_strncpy(name, locName, buffSize - 1);
5247
5248         }
5249 #ifdef CONFIG_YAFFS_SHORT_NAMES_IN_RAM
5250         else if (obj->shortName[0]) {
5251                 yaffs_strcpy(name, obj->shortName);
5252         }
5253 #endif
5254         else {
5255                 __u8 *buffer = yaffs_GetTempBuffer(obj->myDev, __LINE__);
5256
5257                 yaffs_ObjectHeader *oh = (yaffs_ObjectHeader *) buffer;
5258
5259                 memset(buffer, 0, obj->myDev->nBytesPerChunk);
5260
5261                 if (obj->chunkId >= 0) {
5262                         yaffs_ReadChunkWithTagsFromNAND(obj->myDev,
5263                                                         obj->chunkId, buffer,
5264                                                         NULL);
5265                 }
5266                 yaffs_strncpy(name, oh->name, buffSize - 1);
5267
5268                 yaffs_ReleaseTempBuffer(obj->myDev, buffer, __LINE__);
5269         }
5270
5271         return yaffs_strlen(name);
5272 }
5273
5274 int yaffs_GetObjectFileLength(yaffs_Object * obj)
5275 {
5276
5277         /* Dereference any hard linking */
5278         obj = yaffs_GetEquivalentObject(obj);
5279
5280         if (obj->variantType == YAFFS_OBJECT_TYPE_FILE) {
5281                 return obj->variant.fileVariant.fileSize;
5282         }
5283         if (obj->variantType == YAFFS_OBJECT_TYPE_SYMLINK) {
5284                 return yaffs_strlen(obj->variant.symLinkVariant.alias);
5285         } else {
5286                 /* Only a directory should drop through to here */
5287                 return obj->myDev->nBytesPerChunk;
5288         }
5289 }
5290
5291 int yaffs_GetObjectLinkCount(yaffs_Object * obj)
5292 {
5293         int count = 0;
5294         struct list_head *i;
5295
5296         if (!obj->unlinked) {
5297                 count++;        /* the object itself */
5298         }
5299         list_for_each(i, &obj->hardLinks) {
5300                 count++;        /* add the hard links; */
5301         }
5302         return count;
5303
5304 }
5305
5306 int yaffs_GetObjectInode(yaffs_Object * obj)
5307 {
5308         obj = yaffs_GetEquivalentObject(obj);
5309
5310         return obj->objectId;
5311 }
5312
5313 unsigned yaffs_GetObjectType(yaffs_Object * obj)
5314 {
5315         obj = yaffs_GetEquivalentObject(obj);
5316
5317         switch (obj->variantType) {
5318         case YAFFS_OBJECT_TYPE_FILE:
5319                 return DT_REG;
5320                 break;
5321         case YAFFS_OBJECT_TYPE_DIRECTORY:
5322                 return DT_DIR;
5323                 break;
5324         case YAFFS_OBJECT_TYPE_SYMLINK:
5325                 return DT_LNK;
5326                 break;
5327         case YAFFS_OBJECT_TYPE_HARDLINK:
5328                 return DT_REG;
5329                 break;
5330         case YAFFS_OBJECT_TYPE_SPECIAL:
5331                 if (S_ISFIFO(obj->yst_mode))
5332                         return DT_FIFO;
5333                 if (S_ISCHR(obj->yst_mode))
5334                         return DT_CHR;
5335                 if (S_ISBLK(obj->yst_mode))
5336                         return DT_BLK;
5337                 if (S_ISSOCK(obj->yst_mode))
5338                         return DT_SOCK;
5339         default:
5340                 return DT_REG;
5341                 break;
5342         }
5343 }
5344
5345 YCHAR *yaffs_GetSymlinkAlias(yaffs_Object * obj)
5346 {
5347         obj = yaffs_GetEquivalentObject(obj);
5348         if (obj->variantType == YAFFS_OBJECT_TYPE_SYMLINK) {
5349                 return yaffs_CloneString(obj->variant.symLinkVariant.alias);
5350         } else {
5351                 return yaffs_CloneString(_Y(""));
5352         }
5353 }
5354
5355 #ifndef CONFIG_YAFFS_WINCE
5356
5357 int yaffs_SetAttributes(yaffs_Object * obj, struct iattr *attr)
5358 {
5359         unsigned int valid = attr->ia_valid;
5360
5361         if (valid & ATTR_MODE)
5362                 obj->yst_mode = attr->ia_mode;
5363         if (valid & ATTR_UID)
5364                 obj->yst_uid = attr->ia_uid;
5365         if (valid & ATTR_GID)
5366                 obj->yst_gid = attr->ia_gid;
5367
5368         if (valid & ATTR_ATIME)
5369                 obj->yst_atime = Y_TIME_CONVERT(attr->ia_atime);
5370         if (valid & ATTR_CTIME)
5371                 obj->yst_ctime = Y_TIME_CONVERT(attr->ia_ctime);
5372         if (valid & ATTR_MTIME)
5373                 obj->yst_mtime = Y_TIME_CONVERT(attr->ia_mtime);
5374
5375         if (valid & ATTR_SIZE)
5376                 yaffs_ResizeFile(obj, attr->ia_size);
5377
5378         yaffs_UpdateObjectHeader(obj, NULL, 1, 0, 0);
5379
5380         return YAFFS_OK;
5381
5382 }
5383 int yaffs_GetAttributes(yaffs_Object * obj, struct iattr *attr)
5384 {
5385         unsigned int valid = 0;
5386
5387         attr->ia_mode = obj->yst_mode;
5388         valid |= ATTR_MODE;
5389         attr->ia_uid = obj->yst_uid;
5390         valid |= ATTR_UID;
5391         attr->ia_gid = obj->yst_gid;
5392         valid |= ATTR_GID;
5393
5394         Y_TIME_CONVERT(attr->ia_atime) = obj->yst_atime;
5395         valid |= ATTR_ATIME;
5396         Y_TIME_CONVERT(attr->ia_ctime) = obj->yst_ctime;
5397         valid |= ATTR_CTIME;
5398         Y_TIME_CONVERT(attr->ia_mtime) = obj->yst_mtime;
5399         valid |= ATTR_MTIME;
5400
5401         attr->ia_size = yaffs_GetFileSize(obj);
5402         valid |= ATTR_SIZE;
5403
5404         attr->ia_valid = valid;
5405
5406         return YAFFS_OK;
5407
5408 }
5409
5410 #endif
5411
5412 #if 0
5413 int yaffs_DumpObject(yaffs_Object * obj)
5414 {
5415         YCHAR name[257];
5416
5417         yaffs_GetObjectName(obj, name, 256);
5418
5419         T(YAFFS_TRACE_ALWAYS,
5420           (TSTR
5421            ("Object %d, inode %d \"%s\"\n dirty %d valid %d serial %d sum %d"
5422             " chunk %d type %d size %d\n"
5423             TENDSTR), obj->objectId, yaffs_GetObjectInode(obj), name,
5424            obj->dirty, obj->valid, obj->serial, obj->sum, obj->chunkId,
5425            yaffs_GetObjectType(obj), yaffs_GetObjectFileLength(obj)));
5426
5427         return YAFFS_OK;
5428 }
5429 #endif
5430
5431 /*---------------------------- Initialisation code -------------------------------------- */
5432
5433 static int yaffs_CheckDevFunctions(const yaffs_Device * dev)
5434 {
5435
5436         /* Common functions, gotta have */
5437         if (!dev->eraseBlockInNAND || !dev->initialiseNAND)
5438                 return 0;
5439
5440 #ifdef CONFIG_YAFFS_YAFFS2
5441
5442         /* Can use the "with tags" style interface for yaffs1 or yaffs2 */
5443         if (dev->writeChunkWithTagsToNAND &&
5444             dev->readChunkWithTagsFromNAND &&
5445             !dev->writeChunkToNAND &&
5446             !dev->readChunkFromNAND &&
5447             dev->markNANDBlockBad && dev->queryNANDBlock)
5448                 return 1;
5449 #endif
5450
5451         /* Can use the "spare" style interface for yaffs1 */
5452         if (!dev->isYaffs2 &&
5453             !dev->writeChunkWithTagsToNAND &&
5454             !dev->readChunkWithTagsFromNAND &&
5455             dev->writeChunkToNAND &&
5456             dev->readChunkFromNAND &&
5457             !dev->markNANDBlockBad && !dev->queryNANDBlock)
5458                 return 1;
5459
5460         return 0;               /* bad */
5461 }
5462
5463 int yaffs_GutsInitialise(yaffs_Device * dev)
5464 {
5465         unsigned x;
5466         int bits;
5467         int extraBits;
5468         int nBlocks;
5469
5470         T(YAFFS_TRACE_TRACING, (TSTR("yaffs: yaffs_GutsInitialise()" TENDSTR)));
5471
5472         /* Check stuff that must be set */
5473
5474         if (!dev) {
5475                 T(YAFFS_TRACE_ALWAYS, (TSTR("yaffs: Need a device" TENDSTR)));
5476                 return YAFFS_FAIL;
5477         }
5478
5479         dev->internalStartBlock = dev->startBlock;
5480         dev->internalEndBlock = dev->endBlock;
5481         dev->blockOffset = 0;
5482         dev->chunkOffset = 0;
5483         dev->nFreeChunks = 0;
5484
5485         if (dev->startBlock == 0) {
5486                 dev->internalStartBlock = dev->startBlock + 1;
5487                 dev->internalEndBlock = dev->endBlock + 1;
5488                 dev->blockOffset = 1;
5489                 dev->chunkOffset = dev->nChunksPerBlock;
5490         }
5491
5492         /* Check geometry parameters. */
5493
5494         if ((dev->isYaffs2 && dev->nBytesPerChunk < 1024) || (!dev->isYaffs2 && dev->nBytesPerChunk != 512) || dev->nChunksPerBlock < 2 || dev->nReservedBlocks < 2 || dev->internalStartBlock <= 0 || dev->internalEndBlock <= 0 || dev->internalEndBlock <= (dev->internalStartBlock + dev->nReservedBlocks + 2)      // otherwise it is too small
5495             ) {
5496                 T(YAFFS_TRACE_ALWAYS,
5497                   (TSTR
5498                    ("yaffs: NAND geometry problems: chunk size %d, type is yaffs%s "
5499                     TENDSTR), dev->nBytesPerChunk, dev->isYaffs2 ? "2" : ""));
5500                 return YAFFS_FAIL;
5501         }
5502
5503         if (yaffs_InitialiseNAND(dev) != YAFFS_OK) {
5504                 T(YAFFS_TRACE_ALWAYS,
5505                   (TSTR("yaffs: InitialiseNAND failed" TENDSTR)));
5506                 return YAFFS_FAIL;
5507         }
5508
5509         /* Got the right mix of functions? */
5510         if (!yaffs_CheckDevFunctions(dev)) {
5511                 /* Function missing */
5512                 T(YAFFS_TRACE_ALWAYS,
5513                   (TSTR
5514                    ("yaffs: device function(s) missing or wrong\n" TENDSTR)));
5515
5516                 return YAFFS_FAIL;
5517         }
5518
5519         /* This is really a compilation check. */
5520         if (!yaffs_CheckStructures()) {
5521                 T(YAFFS_TRACE_ALWAYS,
5522                   (TSTR("yaffs_CheckStructures failed\n" TENDSTR)));
5523                 return YAFFS_FAIL;
5524         }
5525
5526         if (dev->isMounted) {
5527                 T(YAFFS_TRACE_ALWAYS,
5528                   (TSTR("yaffs: device already mounted\n" TENDSTR)));
5529                 return YAFFS_FAIL;
5530         }
5531
5532         /* Finished with most checks. One or two more checks happen later on too. */
5533
5534         dev->isMounted = 1;
5535
5536         nBlocks = dev->internalEndBlock - dev->internalStartBlock + 1;
5537
5538         /* OK now calculate a few things for the device
5539          * Calculate chunkGroupBits.
5540          * We need to find the next power of 2 > than internalEndBlock
5541          */
5542
5543         x = dev->nChunksPerBlock * (dev->internalEndBlock + 1);
5544
5545         for (bits = extraBits = 0; x > 1; bits++) {
5546                 if (x & 1)
5547                         extraBits++;
5548                 x >>= 1;
5549         }
5550
5551         if (extraBits > 0)
5552                 bits++;
5553
5554         /* Set up tnode width if wide tnodes are enabled. */
5555         if(!dev->wideTnodesDisabled){
5556                 /* bits must be even so that we end up with 32-bit words */
5557                 if(bits & 1)
5558                         bits++;
5559                 if(bits < 16)
5560                         dev->tnodeWidth = 16;
5561                 else
5562                         dev->tnodeWidth = bits;
5563         }
5564         else
5565                 dev->tnodeWidth = 16;
5566
5567         dev->tnodeMask = (1<<dev->tnodeWidth)-1;
5568
5569         /* Level0 Tnodes are 16 bits or wider (if wide tnodes are enabled),
5570          * so if the bitwidth of the
5571          * chunk range we're using is greater than 16 we need
5572          * to figure out chunk shift and chunkGroupSize
5573          */
5574
5575         if (bits <= dev->tnodeWidth)
5576                 dev->chunkGroupBits = 0;
5577         else
5578                 dev->chunkGroupBits = bits - dev->tnodeWidth;
5579
5580
5581         dev->chunkGroupSize = 1 << dev->chunkGroupBits;
5582
5583         if (dev->nChunksPerBlock < dev->chunkGroupSize) {
5584                 /* We have a problem because the soft delete won't work if
5585                  * the chunk group size > chunks per block.
5586                  * This can be remedied by using larger "virtual blocks".
5587                  */
5588                 T(YAFFS_TRACE_ALWAYS,
5589                   (TSTR("yaffs: chunk group too large\n" TENDSTR)));
5590
5591                 return YAFFS_FAIL;
5592         }
5593
5594         /* OK, we've finished verifying the device, lets continue with initialisation */
5595
5596         /* More device initialisation */
5597         dev->garbageCollections = 0;
5598         dev->passiveGarbageCollections = 0;
5599         dev->currentDirtyChecker = 0;
5600         dev->bufferedBlock = -1;
5601         dev->doingBufferedBlockRewrite = 0;
5602         dev->nDeletedFiles = 0;
5603         dev->nBackgroundDeletions = 0;
5604         dev->nUnlinkedFiles = 0;
5605         dev->eccFixed = 0;
5606         dev->eccUnfixed = 0;
5607         dev->tagsEccFixed = 0;
5608         dev->tagsEccUnfixed = 0;
5609         dev->nErasureFailures = 0;
5610         dev->nErasedBlocks = 0;
5611         dev->isDoingGC = 0;
5612
5613         /* Initialise temporary buffers */
5614         {
5615                 int i;
5616                 for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
5617                         dev->tempBuffer[i].line = 0;    /* not in use */
5618                         dev->tempBuffer[i].buffer =
5619                             YMALLOC(dev->nBytesPerChunk);
5620                 }
5621         }
5622
5623         yaffs_InitialiseBlocks(dev, nBlocks);
5624
5625         yaffs_InitialiseTnodes(dev);
5626
5627         yaffs_InitialiseObjects(dev);
5628
5629         dev->gcCleanupList = YMALLOC(dev->nChunksPerBlock * sizeof(__u32));
5630
5631         if (dev->nShortOpCaches > 0) {
5632                 int i;
5633
5634                 if (dev->nShortOpCaches > YAFFS_MAX_SHORT_OP_CACHES) {
5635                         dev->nShortOpCaches = YAFFS_MAX_SHORT_OP_CACHES;
5636                 }
5637
5638                 dev->srCache =
5639                     YMALLOC(dev->nShortOpCaches * sizeof(yaffs_ChunkCache));
5640
5641                 for (i = 0; i < dev->nShortOpCaches; i++) {
5642                         dev->srCache[i].object = NULL;
5643                         dev->srCache[i].lastUse = 0;
5644                         dev->srCache[i].dirty = 0;
5645                         dev->srCache[i].data = YMALLOC(dev->nBytesPerChunk);
5646                 }
5647                 dev->srLastUse = 0;
5648         }
5649
5650         dev->cacheHits = 0;
5651
5652         /* Initialise the unlinked, root and lost and found directories */
5653         dev->lostNFoundDir = dev->rootDir =  NULL;
5654         dev->unlinkedDir = dev->deletedDir = NULL;
5655
5656         dev->unlinkedDir =
5657             yaffs_CreateFakeDirectory(dev, YAFFS_OBJECTID_UNLINKED, S_IFDIR);
5658         dev->deletedDir =
5659             yaffs_CreateFakeDirectory(dev, YAFFS_OBJECTID_DELETED, S_IFDIR);
5660
5661         dev->rootDir =
5662             yaffs_CreateFakeDirectory(dev, YAFFS_OBJECTID_ROOT,
5663                                       YAFFS_ROOT_MODE | S_IFDIR);
5664         dev->lostNFoundDir =
5665             yaffs_CreateFakeDirectory(dev, YAFFS_OBJECTID_LOSTNFOUND,
5666                                       YAFFS_LOSTNFOUND_MODE | S_IFDIR);
5667         yaffs_AddObjectToDirectory(dev->rootDir, dev->lostNFoundDir);
5668
5669         if (dev->isYaffs2) {
5670                 dev->useHeaderFileSize = 1;
5671         }
5672
5673         /* Now scan the flash.   */
5674         if (dev->isYaffs2)
5675                 yaffs_ScanBackwards(dev);
5676         else
5677                 yaffs_Scan(dev);
5678
5679         /* Zero out stats */
5680         dev->nPageReads = 0;
5681         dev->nPageWrites = 0;
5682         dev->nBlockErasures = 0;
5683         dev->nGCCopies = 0;
5684         dev->nRetriedWrites = 0;
5685
5686         dev->nRetiredBlocks = 0;
5687
5688         yaffs_VerifyFreeChunks(dev);
5689
5690         T(YAFFS_TRACE_TRACING,
5691           (TSTR("yaffs: yaffs_GutsInitialise() done.\n" TENDSTR)));
5692         return YAFFS_OK;
5693
5694 }
5695
5696 void yaffs_Deinitialise(yaffs_Device * dev)
5697 {
5698         if (dev->isMounted) {
5699                 int i;
5700
5701                 yaffs_DeinitialiseBlocks(dev);
5702                 yaffs_DeinitialiseTnodes(dev);
5703                 yaffs_DeinitialiseObjects(dev);
5704                 if (dev->nShortOpCaches > 0) {
5705
5706                         for (i = 0; i < dev->nShortOpCaches; i++) {
5707                                 YFREE(dev->srCache[i].data);
5708                         }
5709
5710                         YFREE(dev->srCache);
5711                 }
5712
5713                 YFREE(dev->gcCleanupList);
5714
5715                 for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
5716                         YFREE(dev->tempBuffer[i].buffer);
5717                 }
5718
5719                 dev->isMounted = 0;
5720         }
5721
5722 }
5723
5724 static int yaffs_CountFreeChunks(yaffs_Device * dev)
5725 {
5726         int nFree;
5727         int b;
5728
5729         yaffs_BlockInfo *blk;
5730
5731         for (nFree = 0, b = dev->internalStartBlock; b <= dev->internalEndBlock;
5732              b++) {
5733                 blk = yaffs_GetBlockInfo(dev, b);
5734
5735                 switch (blk->blockState) {
5736                 case YAFFS_BLOCK_STATE_EMPTY:
5737                 case YAFFS_BLOCK_STATE_ALLOCATING:
5738                 case YAFFS_BLOCK_STATE_COLLECTING:
5739                 case YAFFS_BLOCK_STATE_FULL:
5740                         nFree +=
5741                             (dev->nChunksPerBlock - blk->pagesInUse +
5742                              blk->softDeletions);
5743                         break;
5744                 default:
5745                         break;
5746                 }
5747
5748         }
5749
5750         return nFree;
5751 }
5752
5753 int yaffs_GetNumberOfFreeChunks(yaffs_Device * dev)
5754 {
5755         /* This is what we report to the outside world */
5756
5757         int nFree;
5758         int nDirtyCacheChunks;
5759
5760 #if 1
5761         nFree = dev->nFreeChunks;
5762 #else
5763         nFree = yaffs_CountFreeChunks(dev);
5764 #endif
5765
5766         nFree += dev->nDeletedFiles;
5767
5768         /* Now count the number of dirty chunks in the cache and subtract those */
5769
5770         {
5771                 int i;
5772                 for (nDirtyCacheChunks = 0, i = 0; i < dev->nShortOpCaches; i++) {
5773                         if (dev->srCache[i].dirty)
5774                                 nDirtyCacheChunks++;
5775                 }
5776         }
5777
5778         nFree -= nDirtyCacheChunks;
5779
5780         nFree -= ((dev->nReservedBlocks + 1) * dev->nChunksPerBlock);
5781
5782         if (nFree < 0)
5783                 nFree = 0;
5784
5785         return nFree;
5786
5787 }
5788
5789 static int yaffs_freeVerificationFailures;
5790
5791 static void yaffs_VerifyFreeChunks(yaffs_Device * dev)
5792 {
5793         int counted = yaffs_CountFreeChunks(dev);
5794
5795         int difference = dev->nFreeChunks - counted;
5796
5797         if (difference) {
5798                 T(YAFFS_TRACE_ALWAYS,
5799                   (TSTR("Freechunks verification failure %d %d %d" TENDSTR),
5800                    dev->nFreeChunks, counted, difference));
5801                 yaffs_freeVerificationFailures++;
5802         }
5803 }
5804
5805 /*---------------------------------------- YAFFS test code ----------------------*/
5806
5807 #define yaffs_CheckStruct(structure,syze, name) \
5808            if(sizeof(structure) != syze) \
5809                { \
5810                  T(YAFFS_TRACE_ALWAYS,(TSTR("%s should be %d but is %d\n" TENDSTR),\
5811                  name,syze,sizeof(structure))); \
5812                  return YAFFS_FAIL; \
5813                 }
5814
5815 static int yaffs_CheckStructures(void)
5816 {
5817 /*      yaffs_CheckStruct(yaffs_Tags,8,"yaffs_Tags") */
5818 /*      yaffs_CheckStruct(yaffs_TagsUnion,8,"yaffs_TagsUnion") */
5819 /*      yaffs_CheckStruct(yaffs_Spare,16,"yaffs_Spare") */
5820 #ifndef CONFIG_YAFFS_TNODE_LIST_DEBUG
5821         yaffs_CheckStruct(yaffs_Tnode, 2 * YAFFS_NTNODES_LEVEL0, "yaffs_Tnode")
5822 #endif
5823             yaffs_CheckStruct(yaffs_ObjectHeader, 512, "yaffs_ObjectHeader")
5824
5825             return YAFFS_OK;
5826 }