yaffs_guts.c

   1 /*
   2  * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
   3  *
   4  * Copyright (C) 2002-2010 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 #include "yportenv.h"
  14 #include "yaffs_trace.h"
  15
  16 #include "yaffsinterface.h"
  17 #include "yaffs_guts.h"
  18 #include "yaffs_tagsvalidity.h"
  19 #include "yaffs_getblockinfo.h"
  20
  21 #include "yaffs_tagscompat.h"
  22
  23 #include "yaffs_nand.h"
  24
  25 #include "yaffs_yaffs1.h"
  26 #include "yaffs_yaffs2.h"
  27 #include "yaffs_bitmap.h"
  28 #include "yaffs_verify.h"
  29
  30 #include "yaffs_nand.h"
  31 #include "yaffs_packedtags2.h"
  32
  33 #include "yaffs_nameval.h"
  34 #include "yaffs_allocator.h"
  35
  36 /* Note YAFFS_GC_GOOD_ENOUGH must be <= YAFFS_GC_PASSIVE_THRESHOLD */
  37 #define YAFFS_GC_GOOD_ENOUGH 2
  38 #define YAFFS_GC_PASSIVE_THRESHOLD 4
  39
  40 #include "yaffs_ecc.h"
  41
  42
  43
  44 /* Robustification (if it ever comes about...) */
  45 static void yaffs_RetireBlock(yaffs_Device *dev, int blockInNAND);
  46 static void yaffs_HandleWriteChunkError(yaffs_Device *dev, int chunkInNAND,
  47                 int erasedOk);
  48 static void yaffs_HandleWriteChunkOk(yaffs_Device *dev, int chunkInNAND,
  49                                 const __u8 *data,
  50                                 const yaffs_ExtendedTags *tags);
  51 static void yaffs_HandleUpdateChunk(yaffs_Device *dev, int chunkInNAND,
  52                                 const yaffs_ExtendedTags *tags);
  53
  54 /* Other local prototypes */
  55 static void yaffs_UpdateParent(yaffs_Object *obj);
  56 static int yaffs_UnlinkObject(yaffs_Object *obj);
  57 static int yaffs_ObjectHasCachedWriteData(yaffs_Object *obj);
  58
  59 static int yaffs_WriteNewChunkWithTagsToNAND(yaffs_Device *dev,
  60                                         const __u8 *buffer,
  61                                         yaffs_ExtendedTags *tags,
  62                                         int useReserve);
  63
  64
  65 static yaffs_Object *yaffs_CreateNewObject(yaffs_Device *dev, int number,
  66                                         yaffs_ObjectType type);
  67
  68
  69 static int yaffs_ApplyXMod(yaffs_Device *dev, char *buffer, yaffs_XAttrMod *xmod);
  70
  71 static void yaffs_RemoveObjectFromDirectory(yaffs_Object *obj);
  72 static int yaffs_CheckStructures(void);
  73 static int yaffs_DoGenericObjectDeletion(yaffs_Object *in);
  74
  75 static yaffs_BlockInfo *yaffs_GetBlockInfo(yaffs_Device *dev, int blockNo);
  76
  77
  78 static int yaffs_CheckChunkErased(struct yaffs_DeviceStruct *dev,
  79                                 int chunkInNAND);
  80
  81 static int yaffs_UnlinkWorker(yaffs_Object *obj);
  82
  83 static int yaffs_TagsMatch(const yaffs_ExtendedTags *tags, int objectId,
  84                         int chunkInObject);
  85
  86 static int yaffs_AllocateChunk(yaffs_Device *dev, int useReserve,
  87                                 yaffs_BlockInfo **blockUsedPtr);
  88
  89 static void yaffs_CheckObjectDetailsLoaded(yaffs_Object *in);
  90
  91 static void yaffs_InvalidateWholeChunkCache(yaffs_Object *in);
  92 static void yaffs_InvalidateChunkCache(yaffs_Object *object, int chunkId);
  93
  94 static int yaffs_FindChunkInFile(yaffs_Object *in, int chunkInInode,
  95                                 yaffs_ExtendedTags *tags);
  96
  97 static int yaffs_VerifyChunkWritten(yaffs_Device *dev,
  98                                         int chunkInNAND,
  99                                         const __u8 *data,
 100                                         yaffs_ExtendedTags *tags);
 101
 102
 103 static void yaffs_LoadNameFromObjectHeader(yaffs_Device *dev,YCHAR *name, const YCHAR *ohName, int bufferSize);
 104 static void yaffs_LoadObjectHeaderFromName(yaffs_Device *dev,YCHAR *ohName, const YCHAR *name);
 105
 106
 107 /* Function to calculate chunk and offset */
 108
 109 static void yaffs_AddrToChunk(yaffs_Device *dev, loff_t addr, int *chunkOut,
 110                 __u32 *offsetOut)
 111 {
 112         int chunk;
 113         __u32 offset;
 114
 115         chunk  = (__u32)(addr >> dev->chunkShift);
 116
 117         if (dev->chunkDiv == 1) {
 118                 /* easy power of 2 case */
 119                 offset = (__u32)(addr & dev->chunkMask);
 120         } else {
 121                 /* Non power-of-2 case */
 122
 123                 loff_t chunkBase;
 124
 125                 chunk /= dev->chunkDiv;
 126
 127                 chunkBase = ((loff_t)chunk) * dev->nDataBytesPerChunk;
 128                 offset = (__u32)(addr - chunkBase);
 129         }
 130
 131         *chunkOut = chunk;
 132         *offsetOut = offset;
 133 }
 134
 135 /* Function to return the number of shifts for a power of 2 greater than or
 136  * equal to the given number
 137  * Note we don't try to cater for all possible numbers and this does not have to
 138  * be hellishly efficient.
 139  */
 140
 141 static __u32 ShiftsGE(__u32 x)
 142 {
 143         int extraBits;
 144         int nShifts;
 145
 146         nShifts = extraBits = 0;
 147
 148         while (x > 1) {
 149                 if (x & 1)
 150                         extraBits++;
 151                 x >>= 1;
 152                 nShifts++;
 153         }
 154
 155         if (extraBits)
 156                 nShifts++;
 157
 158         return nShifts;
 159 }
 160
 161 /* Function to return the number of shifts to get a 1 in bit 0
 162  */
 163
 164 static __u32 Shifts(__u32 x)
 165 {
 166         __u32 nShifts;
 167
 168         nShifts =  0;
 169
 170         if (!x)
 171                 return 0;
 172
 173         while (!(x&1)) {
 174                 x >>= 1;
 175                 nShifts++;
 176         }
 177
 178         return nShifts;
 179 }
 180
 181
 182
 183 /*
 184  * Temporary buffer manipulations.
 185  */
 186
 187 static int yaffs_InitialiseTempBuffers(yaffs_Device *dev)
 188 {
 189         int i;
 190         __u8 *buf = (__u8 *)1;
 191
 192         memset(dev->tempBuffer, 0, sizeof(dev->tempBuffer));
 193
 194         for (i = 0; buf && i < YAFFS_N_TEMP_BUFFERS; i++) {
 195                 dev->tempBuffer[i].line = 0;    /* not in use */
 196                 dev->tempBuffer[i].buffer = buf =
 197                     YMALLOC_DMA(dev->param.totalBytesPerChunk);
 198         }
 199
 200         return buf ? YAFFS_OK : YAFFS_FAIL;
 201 }
 202
 203 __u8 *yaffs_GetTempBuffer(yaffs_Device *dev, int lineNo)
 204 {
 205         int i, j;
 206
 207         dev->tempInUse++;
 208         if (dev->tempInUse > dev->maxTemp)
 209                 dev->maxTemp = dev->tempInUse;
 210
 211         for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
 212                 if (dev->tempBuffer[i].line == 0) {
 213                         dev->tempBuffer[i].line = lineNo;
 214                         if ((i + 1) > dev->maxTemp) {
 215                                 dev->maxTemp = i + 1;
 216                                 for (j = 0; j <= i; j++)
 217                                         dev->tempBuffer[j].maxLine =
 218                                             dev->tempBuffer[j].line;
 219                         }
 220
 221                         return dev->tempBuffer[i].buffer;
 222                 }
 223         }
 224
 225         T(YAFFS_TRACE_BUFFERS,
 226           (TSTR("Out of temp buffers at line %d, other held by lines:"),
 227            lineNo));
 228         for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++)
 229                 T(YAFFS_TRACE_BUFFERS, (TSTR(" %d "), dev->tempBuffer[i].line));
 230
 231         T(YAFFS_TRACE_BUFFERS, (TSTR(" " TENDSTR)));
 232
 233         /*
 234          * If we got here then we have to allocate an unmanaged one
 235          * This is not good.
 236          */
 237
 238         dev->unmanagedTempAllocations++;
 239         return YMALLOC(dev->nDataBytesPerChunk);
 240
 241 }
 242
 243 void yaffs_ReleaseTempBuffer(yaffs_Device *dev, __u8 *buffer,
 244                                     int lineNo)
 245 {
 246         int i;
 247
 248         dev->tempInUse--;
 249
 250         for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
 251                 if (dev->tempBuffer[i].buffer == buffer) {
 252                         dev->tempBuffer[i].line = 0;
 253                         return;
 254                 }
 255         }
 256
 257         if (buffer) {
 258                 /* assume it is an unmanaged one. */
 259                 T(YAFFS_TRACE_BUFFERS,
 260                   (TSTR("Releasing unmanaged temp buffer in line %d" TENDSTR),
 261                    lineNo));
 262                 YFREE(buffer);
 263                 dev->unmanagedTempDeallocations++;
 264         }
 265
 266 }
 267
 268 /*
 269  * Determine if we have a managed buffer.
 270  */
 271 int yaffs_IsManagedTempBuffer(yaffs_Device *dev, const __u8 *buffer)
 272 {
 273         int i;
 274
 275         for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
 276                 if (dev->tempBuffer[i].buffer == buffer)
 277                         return 1;
 278         }
 279
 280         for (i = 0; i < dev->param.nShortOpCaches; i++) {
 281                 if (dev->srCache[i].data == buffer)
 282                         return 1;
 283         }
 284
 285         if (buffer == dev->checkpointBuffer)
 286                 return 1;
 287
 288         T(YAFFS_TRACE_ALWAYS,
 289                 (TSTR("yaffs: unmaged buffer detected.\n" TENDSTR)));
 290         return 0;
 291 }
 292
 293 /*
 294  * Verification code
 295  */
 296
 297
 298
 299
 300 /*
 301  *  Simple hash function. Needs to have a reasonable spread
 302  */
 303
 304 static Y_INLINE int yaffs_HashFunction(int n)
 305 {
 306         n = abs(n);
 307         return n % YAFFS_NOBJECT_BUCKETS;
 308 }
 309
 310 /*
 311  * Access functions to useful fake objects.
 312  * Note that root might have a presence in NAND if permissions are set.
 313  */
 314
 315 yaffs_Object *yaffs_Root(yaffs_Device *dev)
 316 {
 317         return dev->rootDir;
 318 }
 319
 320 yaffs_Object *yaffs_LostNFound(yaffs_Device *dev)
 321 {
 322         return dev->lostNFoundDir;
 323 }
 324
 325
 326 /*
 327  *  Erased NAND checking functions
 328  */
 329
 330 int yaffs_CheckFF(__u8 *buffer, int nBytes)
 331 {
 332         /* Horrible, slow implementation */
 333         while (nBytes--) {
 334                 if (*buffer != 0xFF)
 335                         return 0;
 336                 buffer++;
 337         }
 338         return 1;
 339 }
 340
 341 static int yaffs_CheckChunkErased(struct yaffs_DeviceStruct *dev,
 342                                 int chunkInNAND)
 343 {
 344         int retval = YAFFS_OK;
 345         __u8 *data = yaffs_GetTempBuffer(dev, __LINE__);
 346         yaffs_ExtendedTags tags;
 347         int result;
 348
 349         result = yaffs_ReadChunkWithTagsFromNAND(dev, chunkInNAND, data, &tags);
 350
 351         if (tags.eccResult > YAFFS_ECC_RESULT_NO_ERROR)
 352                 retval = YAFFS_FAIL;
 353
 354         if (!yaffs_CheckFF(data, dev->nDataBytesPerChunk) || tags.chunkUsed) {
 355                 T(YAFFS_TRACE_NANDACCESS,
 356                   (TSTR("Chunk %d not erased" TENDSTR), chunkInNAND));
 357                 retval = YAFFS_FAIL;
 358         }
 359
 360         yaffs_ReleaseTempBuffer(dev, data, __LINE__);
 361
 362         return retval;
 363
 364 }
 365
 366
 367 static int yaffs_VerifyChunkWritten(yaffs_Device *dev,
 368                                         int chunkInNAND,
 369                                         const __u8 *data,
 370                                         yaffs_ExtendedTags *tags)
 371 {
 372         int retval = YAFFS_OK;
 373         yaffs_ExtendedTags tempTags;
 374         __u8 *buffer = yaffs_GetTempBuffer(dev,__LINE__);
 375         int result;
 376
 377         result = yaffs_ReadChunkWithTagsFromNAND(dev,chunkInNAND,buffer,&tempTags);
 378         if(memcmp(buffer,data,dev->nDataBytesPerChunk) ||
 379                 tempTags.objectId != tags->objectId ||
 380                 tempTags.chunkId  != tags->chunkId ||
 381                 tempTags.byteCount != tags->byteCount)
 382                 retval = YAFFS_FAIL;
 383
 384         yaffs_ReleaseTempBuffer(dev, buffer, __LINE__);
 385
 386         return retval;
 387 }
 388
 389 static int yaffs_WriteNewChunkWithTagsToNAND(struct yaffs_DeviceStruct *dev,
 390                                         const __u8 *data,
 391                                         yaffs_ExtendedTags *tags,
 392                                         int useReserve)
 393 {
 394         int attempts = 0;
 395         int writeOk = 0;
 396         int chunk;
 397
 398         yaffs2_InvalidateCheckpoint(dev);
 399
 400         do {
 401                 yaffs_BlockInfo *bi = 0;
 402                 int erasedOk = 0;
 403
 404                 chunk = yaffs_AllocateChunk(dev, useReserve, &bi);
 405                 if (chunk < 0) {
 406                         /* no space */
 407                         break;
 408                 }
 409
 410                 /* First check this chunk is erased, if it needs
 411                  * checking.  The checking policy (unless forced
 412                  * always on) is as follows:
 413                  *
 414                  * Check the first page we try to write in a block.
 415                  * If the check passes then we don't need to check any
 416                  * more.        If the check fails, we check again...
 417                  * If the block has been erased, we don't need to check.
 418                  *
 419                  * However, if the block has been prioritised for gc,
 420                  * then we think there might be something odd about
 421                  * this block and stop using it.
 422                  *
 423                  * Rationale: We should only ever see chunks that have
 424                  * not been erased if there was a partially written
 425                  * chunk due to power loss.  This checking policy should
 426                  * catch that case with very few checks and thus save a
 427                  * lot of checks that are most likely not needed.
 428                  *
 429                  * Mods to the above
 430                  * If an erase check fails or the write fails we skip the
 431                  * rest of the block.
 432                  */
 433
 434                 /* let's give it a try */
 435                 attempts++;
 436
 437 #ifdef CONFIG_YAFFS_ALWAYS_CHECK_CHUNK_ERASED
 438                 bi->skipErasedCheck = 0;
 439 #endif
 440                 if (!bi->skipErasedCheck) {
 441                         erasedOk = yaffs_CheckChunkErased(dev, chunk);
 442                         if (erasedOk != YAFFS_OK) {
 443                                 T(YAFFS_TRACE_ERROR,
 444                                 (TSTR("**>> yaffs chunk %d was not erased"
 445                                 TENDSTR), chunk));
 446
 447                                 /* If not erased, delete this one,
 448                                  * skip rest of block and
 449                                  * try another chunk */
 450                                  yaffs_DeleteChunk(dev,chunk,1,__LINE__);
 451                                  yaffs_SkipRestOfBlock(dev);
 452                                 continue;
 453                         }
 454                 }
 455
 456                 writeOk = yaffs_WriteChunkWithTagsToNAND(dev, chunk,
 457                                 data, tags);
 458
 459                 if(!bi->skipErasedCheck)
 460                         writeOk = yaffs_VerifyChunkWritten(dev, chunk, data, tags);
 461
 462                 if (writeOk != YAFFS_OK) {
 463                         /* Clean up aborted write, skip to next block and
 464                          * try another chunk */
 465                         yaffs_HandleWriteChunkError(dev, chunk, erasedOk);
 466                         continue;
 467                 }
 468
 469                 bi->skipErasedCheck = 1;
 470
 471                 /* Copy the data into the robustification buffer */
 472                 yaffs_HandleWriteChunkOk(dev, chunk, data, tags);
 473
 474         } while (writeOk != YAFFS_OK &&
 475                 (yaffs_wr_attempts <= 0 || attempts <= yaffs_wr_attempts));
 476
 477         if (!writeOk)
 478                 chunk = -1;
 479
 480         if (attempts > 1) {
 481                 T(YAFFS_TRACE_ERROR,
 482                         (TSTR("**>> yaffs write required %d attempts" TENDSTR),
 483                         attempts));
 484
 485                 dev->nRetriedWrites += (attempts - 1);
 486         }
 487
 488         return chunk;
 489 }
 490
 491
 492
 493 /*
 494  * Block retiring for handling a broken block.
 495  */
 496
 497 static void yaffs_RetireBlock(yaffs_Device *dev, int blockInNAND)
 498 {
 499         yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, blockInNAND);
 500
 501         yaffs2_InvalidateCheckpoint(dev);
 502
 503         yaffs2_ClearOldestDirtySequence(dev,bi);
 504
 505         if (yaffs_MarkBlockBad(dev, blockInNAND) != YAFFS_OK) {
 506                 if (yaffs_EraseBlockInNAND(dev, blockInNAND) != YAFFS_OK) {
 507                         T(YAFFS_TRACE_ALWAYS, (TSTR(
 508                                 "yaffs: Failed to mark bad and erase block %d"
 509                                 TENDSTR), blockInNAND));
 510                 } else {
 511                         yaffs_ExtendedTags tags;
 512                         int chunkId = blockInNAND * dev->param.nChunksPerBlock;
 513
 514                         __u8 *buffer = yaffs_GetTempBuffer(dev, __LINE__);
 515
 516                         memset(buffer, 0xff, dev->nDataBytesPerChunk);
 517                         yaffs_InitialiseTags(&tags);
 518                         tags.sequenceNumber = YAFFS_SEQUENCE_BAD_BLOCK;
 519                         if (dev->param.writeChunkWithTagsToNAND(dev, chunkId -
 520                                 dev->chunkOffset, buffer, &tags) != YAFFS_OK)
 521                                 T(YAFFS_TRACE_ALWAYS, (TSTR("yaffs: Failed to "
 522                                         TCONT("write bad block marker to block %d")
 523                                         TENDSTR), blockInNAND));
 524
 525                         yaffs_ReleaseTempBuffer(dev, buffer, __LINE__);
 526                 }
 527         }
 528
 529         bi->blockState = YAFFS_BLOCK_STATE_DEAD;
 530         bi->gcPrioritise = 0;
 531         bi->needsRetiring = 0;
 532
 533         dev->nRetiredBlocks++;
 534 }
 535
 536 /*
 537  * Functions for robustisizing TODO
 538  *
 539  */
 540
 541 static void yaffs_HandleWriteChunkOk(yaffs_Device *dev, int chunkInNAND,
 542                                 const __u8 *data,
 543                                 const yaffs_ExtendedTags *tags)
 544 {
 545         dev=dev;
 546         chunkInNAND=chunkInNAND;
 547         data=data;
 548         tags=tags;
 549 }
 550
 551 static void yaffs_HandleUpdateChunk(yaffs_Device *dev, int chunkInNAND,
 552                                 const yaffs_ExtendedTags *tags)
 553 {
 554         dev=dev;
 555         chunkInNAND=chunkInNAND;
 556         tags=tags;
 557 }
 558
 559 void yaffs_HandleChunkError(yaffs_Device *dev, yaffs_BlockInfo *bi)
 560 {
 561         if (!bi->gcPrioritise) {
 562                 bi->gcPrioritise = 1;
 563                 dev->hasPendingPrioritisedGCs = 1;
 564                 bi->chunkErrorStrikes++;
 565
 566                 if (bi->chunkErrorStrikes > 3) {
 567                         bi->needsRetiring = 1; /* Too many stikes, so retire this */
 568                         T(YAFFS_TRACE_ALWAYS, (TSTR("yaffs: Block struck out" TENDSTR)));
 569
 570                 }
 571         }
 572 }
 573
 574 static void yaffs_HandleWriteChunkError(yaffs_Device *dev, int chunkInNAND,
 575                 int erasedOk)
 576 {
 577         int blockInNAND = chunkInNAND / dev->param.nChunksPerBlock;
 578         yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, blockInNAND);
 579
 580         yaffs_HandleChunkError(dev, bi);
 581
 582         if (erasedOk) {
 583                 /* Was an actual write failure, so mark the block for retirement  */
 584                 bi->needsRetiring = 1;
 585                 T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
 586                   (TSTR("**>> Block %d needs retiring" TENDSTR), blockInNAND));
 587         }
 588
 589         /* Delete the chunk */
 590         yaffs_DeleteChunk(dev, chunkInNAND, 1, __LINE__);
 591         yaffs_SkipRestOfBlock(dev);
 592 }
 593
 594
 595 /*---------------- Name handling functions ------------*/
 596
 597 static __u16 yaffs_CalcNameSum(const YCHAR *name)
 598 {
 599         __u16 sum = 0;
 600         __u16 i = 1;
 601
 602         const YUCHAR *bname = (const YUCHAR *) name;
 603         if (bname) {
 604                 while ((*bname) && (i < (YAFFS_MAX_NAME_LENGTH/2))) {
 605
 606 #ifdef CONFIG_YAFFS_CASE_INSENSITIVE
 607                         sum += yaffs_toupper(*bname) * i;
 608 #else
 609                         sum += (*bname) * i;
 610 #endif
 611                         i++;
 612                         bname++;
 613                 }
 614         }
 615         return sum;
 616 }
 617
 618 void yaffs_SetObjectName(yaffs_Object *obj, const YCHAR *name)
 619 {
 620 #ifdef CONFIG_YAFFS_SHORT_NAMES_IN_RAM
 621         memset(obj->shortName, 0, sizeof(YCHAR) * (YAFFS_SHORT_NAME_LENGTH+1));
 622         if (name && yaffs_strnlen(name,YAFFS_SHORT_NAME_LENGTH+1) <= YAFFS_SHORT_NAME_LENGTH)
 623                 yaffs_strcpy(obj->shortName, name);
 624         else
 625                 obj->shortName[0] = _Y('\0');
 626 #endif
 627         obj->sum = yaffs_CalcNameSum(name);
 628 }
 629
 630 void yaffs_SetObjectNameFromOH(yaffs_Object *obj, const yaffs_ObjectHeader *oh)
 631 {
 632 #ifdef CONFIG_YAFFS_AUTO_UNICODE
 633         YCHAR tmpName[YAFFS_MAX_NAME_LENGTH+1];
 634         memset(tmpName,0,sizeof(tmpName));
 635         yaffs_LoadNameFromObjectHeader(obj->myDev,tmpName,oh->name,YAFFS_MAX_NAME_LENGTH+1);
 636         yaffs_SetObjectName(obj,tmpName);
 637 #else
 638         yaffs_SetObjectName(obj,oh->name);
 639 #endif
 640 }
 641
 642 /*-------------------- TNODES -------------------
 643
 644  * List of spare tnodes
 645  * The list is hooked together using the first pointer
 646  * in the tnode.
 647  */
 648
 649
 650 yaffs_Tnode *yaffs_GetTnode(yaffs_Device *dev)
 651 {
 652         yaffs_Tnode *tn = yaffs_AllocateRawTnode(dev);
 653         if (tn){
 654                 memset(tn, 0, dev->tnodeSize);
 655                 dev->nTnodes++;
 656         }
 657
 658         dev->nCheckpointBlocksRequired = 0; /* force recalculation*/
 659
 660         return tn;
 661 }
 662
 663 /* FreeTnode frees up a tnode and puts it back on the free list */
 664 static void yaffs_FreeTnode(yaffs_Device *dev, yaffs_Tnode *tn)
 665 {
 666         yaffs_FreeRawTnode(dev,tn);
 667         dev->nTnodes--;
 668         dev->nCheckpointBlocksRequired = 0; /* force recalculation*/
 669 }
 670
 671 static void yaffs_DeinitialiseTnodesAndObjects(yaffs_Device *dev)
 672 {
 673         yaffs_DeinitialiseRawTnodesAndObjects(dev);
 674         dev->nObjects = 0;
 675         dev->nTnodes = 0;
 676 }
 677
 678
 679 void yaffs_LoadLevel0Tnode(yaffs_Device *dev, yaffs_Tnode *tn, unsigned pos,
 680                 unsigned val)
 681 {
 682         __u32 *map = (__u32 *)tn;
 683         __u32 bitInMap;
 684         __u32 bitInWord;
 685         __u32 wordInMap;
 686         __u32 mask;
 687
 688         pos &= YAFFS_TNODES_LEVEL0_MASK;
 689         val >>= dev->chunkGroupBits;
 690
 691         bitInMap = pos * dev->tnodeWidth;
 692         wordInMap = bitInMap / 32;
 693         bitInWord = bitInMap & (32 - 1);
 694
 695         mask = dev->tnodeMask << bitInWord;
 696
 697         map[wordInMap] &= ~mask;
 698         map[wordInMap] |= (mask & (val << bitInWord));
 699
 700         if (dev->tnodeWidth > (32 - bitInWord)) {
 701                 bitInWord = (32 - bitInWord);
 702                 wordInMap++;;
 703                 mask = dev->tnodeMask >> (/*dev->tnodeWidth -*/ bitInWord);
 704                 map[wordInMap] &= ~mask;
 705                 map[wordInMap] |= (mask & (val >> bitInWord));
 706         }
 707 }
 708
 709 __u32 yaffs_GetChunkGroupBase(yaffs_Device *dev, yaffs_Tnode *tn,
 710                 unsigned pos)
 711 {
 712         __u32 *map = (__u32 *)tn;
 713         __u32 bitInMap;
 714         __u32 bitInWord;
 715         __u32 wordInMap;
 716         __u32 val;
 717
 718         pos &= YAFFS_TNODES_LEVEL0_MASK;
 719
 720         bitInMap = pos * dev->tnodeWidth;
 721         wordInMap = bitInMap / 32;
 722         bitInWord = bitInMap & (32 - 1);
 723
 724         val = map[wordInMap] >> bitInWord;
 725
 726         if      (dev->tnodeWidth > (32 - bitInWord)) {
 727                 bitInWord = (32 - bitInWord);
 728                 wordInMap++;;
 729                 val |= (map[wordInMap] << bitInWord);
 730         }
 731
 732         val &= dev->tnodeMask;
 733         val <<= dev->chunkGroupBits;
 734
 735         return val;
 736 }
 737
 738 /* ------------------- End of individual tnode manipulation -----------------*/
 739
 740 /* ---------Functions to manipulate the look-up tree (made up of tnodes) ------
 741  * The look up tree is represented by the top tnode and the number of topLevel
 742  * in the tree. 0 means only the level 0 tnode is in the tree.
 743  */
 744
 745 /* FindLevel0Tnode finds the level 0 tnode, if one exists. */
 746 yaffs_Tnode *yaffs_FindLevel0Tnode(yaffs_Device *dev,
 747                                         yaffs_FileStructure *fStruct,
 748                                         __u32 chunkId)
 749 {
 750         yaffs_Tnode *tn = fStruct->top;
 751         __u32 i;
 752         int requiredTallness;
 753         int level = fStruct->topLevel;
 754
 755         dev=dev;
 756
 757         /* Check sane level and chunk Id */
 758         if (level < 0 || level > YAFFS_TNODES_MAX_LEVEL)
 759                 return NULL;
 760
 761         if (chunkId > YAFFS_MAX_CHUNK_ID)
 762                 return NULL;
 763
 764         /* First check we're tall enough (ie enough topLevel) */
 765
 766         i = chunkId >> YAFFS_TNODES_LEVEL0_BITS;
 767         requiredTallness = 0;
 768         while (i) {
 769                 i >>= YAFFS_TNODES_INTERNAL_BITS;
 770                 requiredTallness++;
 771         }
 772
 773         if (requiredTallness > fStruct->topLevel)
 774                 return NULL; /* Not tall enough, so we can't find it */
 775
 776         /* Traverse down to level 0 */
 777         while (level > 0 && tn) {
 778                 tn = tn->internal[(chunkId >>
 779                         (YAFFS_TNODES_LEVEL0_BITS +
 780                                 (level - 1) *
 781                                 YAFFS_TNODES_INTERNAL_BITS)) &
 782                         YAFFS_TNODES_INTERNAL_MASK];
 783                 level--;
 784         }
 785
 786         return tn;
 787 }
 788
 789 /* AddOrFindLevel0Tnode finds the level 0 tnode if it exists, otherwise first expands the tree.
 790  * This happens in two steps:
 791  *  1. If the tree isn't tall enough, then make it taller.
 792  *  2. Scan down the tree towards the level 0 tnode adding tnodes if required.
 793  *
 794  * Used when modifying the tree.
 795  *
 796  *  If the tn argument is NULL, then a fresh tnode will be added otherwise the specified tn will
 797  *  be plugged into the ttree.
 798  */
 799
 800 yaffs_Tnode *yaffs_AddOrFindLevel0Tnode(yaffs_Device *dev,
 801                                         yaffs_FileStructure *fStruct,
 802                                         __u32 chunkId,
 803                                         yaffs_Tnode *passedTn)
 804 {
 805         int requiredTallness;
 806         int i;
 807         int l;
 808         yaffs_Tnode *tn;
 809
 810         __u32 x;
 811
 812
 813         /* Check sane level and page Id */
 814         if (fStruct->topLevel < 0 || fStruct->topLevel > YAFFS_TNODES_MAX_LEVEL)
 815                 return NULL;
 816
 817         if (chunkId > YAFFS_MAX_CHUNK_ID)
 818                 return NULL;
 819
 820         /* First check we're tall enough (ie enough topLevel) */
 821
 822         x = chunkId >> YAFFS_TNODES_LEVEL0_BITS;
 823         requiredTallness = 0;
 824         while (x) {
 825                 x >>= YAFFS_TNODES_INTERNAL_BITS;
 826                 requiredTallness++;
 827         }
 828
 829
 830         if (requiredTallness > fStruct->topLevel) {
 831                 /* Not tall enough, gotta make the tree taller */
 832                 for (i = fStruct->topLevel; i < requiredTallness; i++) {
 833
 834                         tn = yaffs_GetTnode(dev);
 835
 836                         if (tn) {
 837                                 tn->internal[0] = fStruct->top;
 838                                 fStruct->top = tn;
 839                                 fStruct->topLevel++;
 840                         } else {
 841                                 T(YAFFS_TRACE_ERROR,
 842                                         (TSTR("yaffs: no more tnodes" TENDSTR)));
 843                                 return NULL;
 844                         }
 845                 }
 846         }
 847
 848         /* Traverse down to level 0, adding anything we need */
 849
 850         l = fStruct->topLevel;
 851         tn = fStruct->top;
 852
 853         if (l > 0) {
 854                 while (l > 0 && tn) {
 855                         x = (chunkId >>
 856                              (YAFFS_TNODES_LEVEL0_BITS +
 857                               (l - 1) * YAFFS_TNODES_INTERNAL_BITS)) &
 858                             YAFFS_TNODES_INTERNAL_MASK;
 859
 860
 861                         if ((l > 1) && !tn->internal[x]) {
 862                                 /* Add missing non-level-zero tnode */
 863                                 tn->internal[x] = yaffs_GetTnode(dev);
 864                                 if(!tn->internal[x])
 865                                         return NULL;
 866                         } else if (l == 1) {
 867                                 /* Looking from level 1 at level 0 */
 868                                 if (passedTn) {
 869                                         /* If we already have one, then release it.*/
 870                                         if (tn->internal[x])
 871                                                 yaffs_FreeTnode(dev, tn->internal[x]);
 872                                         tn->internal[x] = passedTn;
 873
 874                                 } else if (!tn->internal[x]) {
 875                                         /* Don't have one, none passed in */
 876                                         tn->internal[x] = yaffs_GetTnode(dev);
 877                                         if(!tn->internal[x])
 878                                                 return NULL;
 879                                 }
 880                         }
 881
 882                         tn = tn->internal[x];
 883                         l--;
 884                 }
 885         } else {
 886                 /* top is level 0 */
 887                 if (passedTn) {
 888                         memcpy(tn, passedTn, (dev->tnodeWidth * YAFFS_NTNODES_LEVEL0)/8);
 889                         yaffs_FreeTnode(dev, passedTn);
 890                 }
 891         }
 892
 893         return tn;
 894 }
 895
 896 static int yaffs_FindChunkInGroup(yaffs_Device *dev, int theChunk,
 897                                 yaffs_ExtendedTags *tags, int objectId,
 898                                 int chunkInInode)
 899 {
 900         int j;
 901
 902         for (j = 0; theChunk && j < dev->chunkGroupSize; j++) {
 903                 if (yaffs_CheckChunkBit(dev, theChunk / dev->param.nChunksPerBlock,
 904                                 theChunk % dev->param.nChunksPerBlock)) {
 905
 906                         if(dev->chunkGroupSize == 1)
 907                                 return theChunk;
 908                         else {
 909                                 yaffs_ReadChunkWithTagsFromNAND(dev, theChunk, NULL,
 910                                                                 tags);
 911                                 if (yaffs_TagsMatch(tags, objectId, chunkInInode)) {
 912                                         /* found it; */
 913                                         return theChunk;
 914                                 }
 915                         }
 916                 }
 917                 theChunk++;
 918         }
 919         return -1;
 920 }
 921
 922 #if 0
 923 /* Experimental code not being used yet. Might speed up file deletion */
 924 /* DeleteWorker scans backwards through the tnode tree and deletes all the
 925  * chunks and tnodes in the file.
 926  * Returns 1 if the tree was deleted.
 927  * Returns 0 if it stopped early due to hitting the limit and the delete is incomplete.
 928  */
 929
 930 static int yaffs_DeleteWorker(yaffs_Object *in, yaffs_Tnode *tn, __u32 level,
 931                               int chunkOffset, int *limit)
 932 {
 933         int i;
 934         int chunkInInode;
 935         int theChunk;
 936         yaffs_ExtendedTags tags;
 937         int foundChunk;
 938         yaffs_Device *dev = in->myDev;
 939
 940         int allDone = 1;
 941
 942         if (tn) {
 943                 if (level > 0) {
 944                         for (i = YAFFS_NTNODES_INTERNAL - 1; allDone && i >= 0;
 945                              i--) {
 946                                 if (tn->internal[i]) {
 947                                         if (limit && (*limit) < 0) {
 948                                                 allDone = 0;
 949                                         } else {
 950                                                 allDone =
 951                                                         yaffs_DeleteWorker(in,
 952                                                                 tn->
 953                                                                 internal
 954                                                                 [i],
 955                                                                 level -
 956                                                                 1,
 957                                                                 (chunkOffset
 958                                                                         <<
 959                                                                         YAFFS_TNODES_INTERNAL_BITS)
 960                                                                 + i,
 961                                                                 limit);
 962                                         }
 963                                         if (allDone) {
 964                                                 yaffs_FreeTnode(dev,
 965                                                                 tn->
 966                                                                 internal[i]);
 967                                                 tn->internal[i] = NULL;
 968                                         }
 969                                 }
 970                         }
 971                         return (allDone) ? 1 : 0;
 972                 } else if (level == 0) {
 973                         int hitLimit = 0;
 974
 975                         for (i = YAFFS_NTNODES_LEVEL0 - 1; i >= 0 && !hitLimit;
 976                                         i--) {
 977                                 theChunk = yaffs_GetChunkGroupBase(dev, tn, i);
 978                                 if (theChunk) {
 979
 980                                         chunkInInode = (chunkOffset <<
 981                                                 YAFFS_TNODES_LEVEL0_BITS) + i;
 982
 983                                         foundChunk =
 984                                                 yaffs_FindChunkInGroup(dev,
 985                                                                 theChunk,
 986                                                                 &tags,
 987                                                                 in->objectId,
 988                                                                 chunkInInode);
 989
 990                                         if (foundChunk > 0) {
 991                                                 yaffs_DeleteChunk(dev,
 992                                                                   foundChunk, 1,
 993                                                                   __LINE__);
 994                                                 in->nDataChunks--;
 995                                                 if (limit) {
 996                                                         *limit = *limit - 1;
 997                                                         if (*limit <= 0)
 998                                                                 hitLimit = 1;
 999                                                 }
1000
1001                                         }
1002
1003                                         yaffs_LoadLevel0Tnode(dev, tn, i, 0);
1004                                 }
1005
1006                         }
1007                         return (i < 0) ? 1 : 0;
1008
1009                 }
1010
1011         }
1012
1013         return 1;
1014
1015 }
1016
1017 #endif
1018
1019 static void yaffs_SoftDeleteChunk(yaffs_Device *dev, int chunk)
1020 {
1021         yaffs_BlockInfo *theBlock;
1022         unsigned blockNo;
1023
1024         T(YAFFS_TRACE_DELETION, (TSTR("soft delete chunk %d" TENDSTR), chunk));
1025
1026         blockNo =  chunk / dev->param.nChunksPerBlock;
1027         theBlock = yaffs_GetBlockInfo(dev, blockNo);
1028         if (theBlock) {
1029                 theBlock->softDeletions++;
1030                 dev->nFreeChunks++;
1031                 yaffs2_UpdateOldestDirtySequence(dev, blockNo, theBlock);
1032         }
1033 }
1034
1035 /* SoftDeleteWorker scans backwards through the tnode tree and soft deletes all the chunks in the file.
1036  * All soft deleting does is increment the block's softdelete count and pulls the chunk out
1037  * of the tnode.
1038  * Thus, essentially this is the same as DeleteWorker except that the chunks are soft deleted.
1039  */
1040
1041 static int yaffs_SoftDeleteWorker(yaffs_Object *in, yaffs_Tnode *tn,
1042                                   __u32 level, int chunkOffset)
1043 {
1044         int i;
1045         int theChunk;
1046         int allDone = 1;
1047         yaffs_Device *dev = in->myDev;
1048
1049         if (tn) {
1050                 if (level > 0) {
1051
1052                         for (i = YAFFS_NTNODES_INTERNAL - 1; allDone && i >= 0;
1053                              i--) {
1054                                 if (tn->internal[i]) {
1055                                         allDone =
1056                                             yaffs_SoftDeleteWorker(in,
1057                                                                    tn->
1058                                                                    internal[i],
1059                                                                    level - 1,
1060                                                                    (chunkOffset
1061                                                                     <<
1062                                                                     YAFFS_TNODES_INTERNAL_BITS)
1063                                                                    + i);
1064                                         if (allDone) {
1065                                                 yaffs_FreeTnode(dev,
1066                                                                 tn->
1067                                                                 internal[i]);
1068                                                 tn->internal[i] = NULL;
1069                                         } else {
1070                                                 /* Hoosterman... how could this happen? */
1071                                         }
1072                                 }
1073                         }
1074                         return (allDone) ? 1 : 0;
1075                 } else if (level == 0) {
1076
1077                         for (i = YAFFS_NTNODES_LEVEL0 - 1; i >= 0; i--) {
1078                                 theChunk = yaffs_GetChunkGroupBase(dev, tn, i);
1079                                 if (theChunk) {
1080                                         /* Note this does not find the real chunk, only the chunk group.
1081                                          * We make an assumption that a chunk group is not larger than
1082                                          * a block.
1083                                          */
1084                                         yaffs_SoftDeleteChunk(dev, theChunk);
1085                                         yaffs_LoadLevel0Tnode(dev, tn, i, 0);
1086                                 }
1087
1088                         }
1089                         return 1;
1090
1091                 }
1092
1093         }
1094
1095         return 1;
1096
1097 }
1098
1099 static void yaffs_SoftDeleteFile(yaffs_Object *obj)
1100 {
1101         if (obj->deleted &&
1102             obj->variantType == YAFFS_OBJECT_TYPE_FILE && !obj->softDeleted) {
1103                 if (obj->nDataChunks <= 0) {
1104                         /* Empty file with no duplicate object headers, just delete it immediately */
1105                         yaffs_FreeTnode(obj->myDev,
1106                                         obj->variant.fileVariant.top);
1107                         obj->variant.fileVariant.top = NULL;
1108                         T(YAFFS_TRACE_TRACING,
1109                           (TSTR("yaffs: Deleting empty file %d" TENDSTR),
1110                            obj->objectId));
1111                         yaffs_DoGenericObjectDeletion(obj);
1112                 } else {
1113                         yaffs_SoftDeleteWorker(obj,
1114                                                obj->variant.fileVariant.top,
1115                                                obj->variant.fileVariant.
1116                                                topLevel, 0);
1117                         obj->softDeleted = 1;
1118                 }
1119         }
1120 }
1121
1122 /* Pruning removes any part of the file structure tree that is beyond the
1123  * bounds of the file (ie that does not point to chunks).
1124  *
1125  * A file should only get pruned when its size is reduced.
1126  *
1127  * Before pruning, the chunks must be pulled from the tree and the
1128  * level 0 tnode entries must be zeroed out.
1129  * Could also use this for file deletion, but that's probably better handled
1130  * by a special case.
1131  *
1132  * This function is recursive. For levels > 0 the function is called again on
1133  * any sub-tree. For level == 0 we just check if the sub-tree has data.
1134  * If there is no data in a subtree then it is pruned.
1135  */
1136
1137 static yaffs_Tnode *yaffs_PruneWorker(yaffs_Device *dev, yaffs_Tnode *tn,
1138                                 __u32 level, int del0)
1139 {
1140         int i;
1141         int hasData;
1142
1143         if (tn) {
1144                 hasData = 0;
1145
1146                 if(level > 0){
1147                         for (i = 0; i < YAFFS_NTNODES_INTERNAL; i++) {
1148                                 if (tn->internal[i]) {
1149                                         tn->internal[i] =
1150                                                 yaffs_PruneWorker(dev, tn->internal[i],
1151                                                         level - 1,
1152                                                         (i == 0) ? del0 : 1);
1153                                 }
1154
1155                                 if (tn->internal[i])
1156                                         hasData++;
1157                         }
1158                 } else {
1159                         int tnodeSize_u32 = dev->tnodeSize/sizeof(__u32);
1160                         __u32 *map = (__u32 *)tn;
1161
1162                         for(i = 0; !hasData && i < tnodeSize_u32; i++){
1163                                 if(map[i])
1164                                         hasData++;
1165                         }
1166                 }
1167
1168                 if (hasData == 0 && del0) {
1169                         /* Free and return NULL */
1170
1171                         yaffs_FreeTnode(dev, tn);
1172                         tn = NULL;
1173                 }
1174
1175         }
1176
1177         return tn;
1178
1179 }
1180
1181 static int yaffs_PruneFileStructure(yaffs_Device *dev,
1182                                 yaffs_FileStructure *fStruct)
1183 {
1184         int i;
1185         int hasData;
1186         int done = 0;
1187         yaffs_Tnode *tn;
1188
1189         if (fStruct->topLevel > 0) {
1190                 fStruct->top =
1191                     yaffs_PruneWorker(dev, fStruct->top, fStruct->topLevel, 0);
1192
1193                 /* Now we have a tree with all the non-zero branches NULL but the height
1194                  * is the same as it was.
1195                  * Let's see if we can trim internal tnodes to shorten the tree.
1196                  * We can do this if only the 0th element in the tnode is in use
1197                  * (ie all the non-zero are NULL)
1198                  */
1199
1200                 while (fStruct->topLevel && !done) {
1201                         tn = fStruct->top;
1202
1203                         hasData = 0;
1204                         for (i = 1; i < YAFFS_NTNODES_INTERNAL; i++) {
1205                                 if (tn->internal[i])
1206                                         hasData++;
1207                         }
1208
1209                         if (!hasData) {
1210                                 fStruct->top = tn->internal[0];
1211                                 fStruct->topLevel--;
1212                                 yaffs_FreeTnode(dev, tn);
1213                         } else {
1214                                 done = 1;
1215                         }
1216                 }
1217         }
1218
1219         return YAFFS_OK;
1220 }
1221
1222 /*-------------------- End of File Structure functions.-------------------*/
1223
1224
1225 /* AllocateEmptyObject gets us a clean Object. Tries to make allocate more if we run out */
1226 static yaffs_Object *yaffs_AllocateEmptyObject(yaffs_Device *dev)
1227 {
1228         yaffs_Object *obj = yaffs_AllocateRawObject(dev);
1229
1230         if (obj) {
1231                 dev->nObjects++;
1232
1233                 /* Now sweeten it up... */
1234
1235                 memset(obj, 0, sizeof(yaffs_Object));
1236                 obj->beingCreated = 1;
1237
1238                 obj->myDev = dev;
1239                 obj->hdrChunk = 0;
1240                 obj->variantType = YAFFS_OBJECT_TYPE_UNKNOWN;
1241                 YINIT_LIST_HEAD(&(obj->hardLinks));
1242                 YINIT_LIST_HEAD(&(obj->hashLink));
1243                 YINIT_LIST_HEAD(&obj->siblings);
1244
1245
1246                 /* Now make the directory sane */
1247                 if (dev->rootDir) {
1248                         obj->parent = dev->rootDir;
1249                         ylist_add(&(obj->siblings), &dev->rootDir->variant.directoryVariant.children);
1250                 }
1251
1252                 /* Add it to the lost and found directory.
1253                  * NB Can't put root or lostNFound in lostNFound so
1254                  * check if lostNFound exists first
1255                  */
1256                 if (dev->lostNFoundDir)
1257                         yaffs_AddObjectToDirectory(dev->lostNFoundDir, obj);
1258
1259                 obj->beingCreated = 0;
1260         }
1261
1262         dev->nCheckpointBlocksRequired = 0; /* force recalculation*/
1263
1264         return obj;
1265 }
1266
1267 static yaffs_Object *yaffs_CreateFakeDirectory(yaffs_Device *dev, int number,
1268                                                __u32 mode)
1269 {
1270
1271         yaffs_Object *obj =
1272             yaffs_CreateNewObject(dev, number, YAFFS_OBJECT_TYPE_DIRECTORY);
1273         if (obj) {
1274                 obj->fake = 1;          /* it is fake so it might have no NAND presence... */
1275                 obj->renameAllowed = 0; /* ... and we're not allowed to rename it... */
1276                 obj->unlinkAllowed = 0; /* ... or unlink it */
1277                 obj->deleted = 0;
1278                 obj->unlinked = 0;
1279                 obj->yst_mode = mode;
1280                 obj->myDev = dev;
1281                 obj->hdrChunk = 0;      /* Not a valid chunk. */
1282         }
1283
1284         return obj;
1285
1286 }
1287
1288 static void yaffs_UnhashObject(yaffs_Object *obj)
1289 {
1290         int bucket;
1291         yaffs_Device *dev = obj->myDev;
1292
1293         /* If it is still linked into the bucket list, free from the list */
1294         if (!ylist_empty(&obj->hashLink)) {
1295                 ylist_del_init(&obj->hashLink);
1296                 bucket = yaffs_HashFunction(obj->objectId);
1297                 dev->objectBucket[bucket].count--;
1298         }
1299 }
1300
1301 /*  FreeObject frees up a Object and puts it back on the free list */
1302 static void yaffs_FreeObject(yaffs_Object *obj)
1303 {
1304         yaffs_Device *dev = obj->myDev;
1305
1306         T(YAFFS_TRACE_OS, (TSTR("FreeObject %p inode %p"TENDSTR), obj, obj->myInode));
1307
1308         if (!obj)
1309                 YBUG();
1310         if (obj->parent)
1311                 YBUG();
1312         if (!ylist_empty(&obj->siblings))
1313                 YBUG();
1314
1315
1316         if (obj->myInode) {
1317                 /* We're still hooked up to a cached inode.
1318                  * Don't delete now, but mark for later deletion
1319                  */
1320                 obj->deferedFree = 1;
1321                 return;
1322         }
1323
1324         yaffs_UnhashObject(obj);
1325
1326         yaffs_FreeRawObject(dev,obj);
1327         dev->nObjects--;
1328         dev->nCheckpointBlocksRequired = 0; /* force recalculation*/
1329 }
1330
1331
1332 void yaffs_HandleDeferedFree(yaffs_Object *obj)
1333 {
1334         if (obj->deferedFree)
1335                 yaffs_FreeObject(obj);
1336 }
1337
1338 static void yaffs_InitialiseTnodesAndObjects(yaffs_Device *dev)
1339 {
1340         int i;
1341
1342         dev->nObjects = 0;
1343         dev->nTnodes = 0;
1344
1345         yaffs_InitialiseRawTnodesAndObjects(dev);
1346
1347         for (i = 0; i < YAFFS_NOBJECT_BUCKETS; i++) {
1348                 YINIT_LIST_HEAD(&dev->objectBucket[i].list);
1349                 dev->objectBucket[i].count = 0;
1350         }
1351 }
1352
1353 static int yaffs_FindNiceObjectBucket(yaffs_Device *dev)
1354 {
1355         int i;
1356         int l = 999;
1357         int lowest = 999999;
1358
1359
1360         /* Search for the shortest list or one that
1361          * isn't too long.
1362          */
1363
1364         for (i = 0; i < 10 && lowest > 4; i++) {
1365                 dev->bucketFinder++;
1366                 dev->bucketFinder %= YAFFS_NOBJECT_BUCKETS;
1367                 if (dev->objectBucket[dev->bucketFinder].count < lowest) {
1368                         lowest = dev->objectBucket[dev->bucketFinder].count;
1369                         l = dev->bucketFinder;
1370                 }
1371
1372         }
1373
1374         return l;
1375 }
1376
1377 static int yaffs_CreateNewObjectNumber(yaffs_Device *dev)
1378 {
1379         int bucket = yaffs_FindNiceObjectBucket(dev);
1380
1381         /* Now find an object value that has not already been taken
1382          * by scanning the list.
1383          */
1384
1385         int found = 0;
1386         struct ylist_head *i;
1387
1388         __u32 n = (__u32) bucket;
1389
1390         /* yaffs_CheckObjectHashSanity();  */
1391
1392         while (!found) {
1393                 found = 1;
1394                 n += YAFFS_NOBJECT_BUCKETS;
1395                 if (1 || dev->objectBucket[bucket].count > 0) {
1396                         ylist_for_each(i, &dev->objectBucket[bucket].list) {
1397                                 /* If there is already one in the list */
1398                                 if (i && ylist_entry(i, yaffs_Object,
1399                                                 hashLink)->objectId == n) {
1400                                         found = 0;
1401                                 }
1402                         }
1403                 }
1404         }
1405
1406         return n;
1407 }
1408
1409 static void yaffs_HashObject(yaffs_Object *in)
1410 {
1411         int bucket = yaffs_HashFunction(in->objectId);
1412         yaffs_Device *dev = in->myDev;
1413
1414         ylist_add(&in->hashLink, &dev->objectBucket[bucket].list);
1415         dev->objectBucket[bucket].count++;
1416 }
1417
1418 yaffs_Object *yaffs_FindObjectByNumber(yaffs_Device *dev, __u32 number)
1419 {
1420         int bucket = yaffs_HashFunction(number);
1421         struct ylist_head *i;
1422         yaffs_Object *in;
1423
1424         ylist_for_each(i, &dev->objectBucket[bucket].list) {
1425                 /* Look if it is in the list */
1426                 if (i) {
1427                         in = ylist_entry(i, yaffs_Object, hashLink);
1428                         if (in->objectId == number) {
1429
1430                                 /* Don't tell the VFS about this one if it is defered free */
1431                                 if (in->deferedFree)
1432                                         return NULL;
1433
1434                                 return in;
1435                         }
1436                 }
1437         }
1438
1439         return NULL;
1440 }
1441
1442 yaffs_Object *yaffs_CreateNewObject(yaffs_Device *dev, int number,
1443                                     yaffs_ObjectType type)
1444 {
1445         yaffs_Object *theObject=NULL;
1446         yaffs_Tnode *tn = NULL;
1447
1448         if (number < 0)
1449                 number = yaffs_CreateNewObjectNumber(dev);
1450
1451         if (type == YAFFS_OBJECT_TYPE_FILE) {
1452                 tn = yaffs_GetTnode(dev);
1453                 if (!tn)
1454                         return NULL;
1455         }
1456
1457         theObject = yaffs_AllocateEmptyObject(dev);
1458         if (!theObject){
1459                 if(tn)
1460                         yaffs_FreeTnode(dev,tn);
1461                 return NULL;
1462         }
1463
1464
1465         if (theObject) {
1466                 theObject->fake = 0;
1467                 theObject->renameAllowed = 1;
1468                 theObject->unlinkAllowed = 1;
1469                 theObject->objectId = number;
1470                 yaffs_HashObject(theObject);
1471                 theObject->variantType = type;
1472 #ifdef CONFIG_YAFFS_WINCE
1473                 yfsd_WinFileTimeNow(theObject->win_atime);
1474                 theObject->win_ctime[0] = theObject->win_mtime[0] =
1475                     theObject->win_atime[0];
1476                 theObject->win_ctime[1] = theObject->win_mtime[1] =
1477                     theObject->win_atime[1];
1478
1479 #else
1480
1481                 theObject->yst_atime = theObject->yst_mtime =
1482                     theObject->yst_ctime = Y_CURRENT_TIME;
1483 #endif
1484                 switch (type) {
1485                 case YAFFS_OBJECT_TYPE_FILE:
1486                         theObject->variant.fileVariant.fileSize = 0;
1487                         theObject->variant.fileVariant.scannedFileSize = 0;
1488                         theObject->variant.fileVariant.shrinkSize = 0xFFFFFFFF; /* max __u32 */
1489                         theObject->variant.fileVariant.topLevel = 0;
1490                         theObject->variant.fileVariant.top = tn;
1491                         break;
1492                 case YAFFS_OBJECT_TYPE_DIRECTORY:
1493                         YINIT_LIST_HEAD(&theObject->variant.directoryVariant.
1494                                         children);
1495                         YINIT_LIST_HEAD(&theObject->variant.directoryVariant.
1496                                         dirty);
1497                         break;
1498                 case YAFFS_OBJECT_TYPE_SYMLINK:
1499                 case YAFFS_OBJECT_TYPE_HARDLINK:
1500                 case YAFFS_OBJECT_TYPE_SPECIAL:
1501                         /* No action required */
1502                         break;
1503                 case YAFFS_OBJECT_TYPE_UNKNOWN:
1504                         /* todo this should not happen */
1505                         break;
1506                 }
1507         }
1508
1509         return theObject;
1510 }
1511
1512 yaffs_Object *yaffs_FindOrCreateObjectByNumber(yaffs_Device *dev,
1513                                                 int number,
1514                                                 yaffs_ObjectType type)
1515 {
1516         yaffs_Object *theObject = NULL;
1517
1518         if (number > 0)
1519                 theObject = yaffs_FindObjectByNumber(dev, number);
1520
1521         if (!theObject)
1522                 theObject = yaffs_CreateNewObject(dev, number, type);
1523
1524         return theObject;
1525
1526 }
1527
1528
1529 YCHAR *yaffs_CloneString(const YCHAR *str)
1530 {
1531         YCHAR *newStr = NULL;
1532         int len;
1533
1534         if (!str)
1535                 str = _Y("");
1536
1537         len = yaffs_strnlen(str,YAFFS_MAX_ALIAS_LENGTH);
1538         newStr = YMALLOC((len + 1) * sizeof(YCHAR));
1539         if (newStr){
1540                 yaffs_strncpy(newStr, str,len);
1541                 newStr[len] = 0;
1542         }
1543         return newStr;
1544
1545 }
1546
1547 /*
1548  * Mknod (create) a new object.
1549  * equivalentObject only has meaning for a hard link;
1550  * aliasString only has meaning for a symlink.
1551  * rdev only has meaning for devices (a subset of special objects)
1552  */
1553
1554 static yaffs_Object *yaffs_MknodObject(yaffs_ObjectType type,
1555                                        yaffs_Object *parent,
1556                                        const YCHAR *name,
1557                                        __u32 mode,
1558                                        __u32 uid,
1559                                        __u32 gid,
1560                                        yaffs_Object *equivalentObject,
1561                                        const YCHAR *aliasString, __u32 rdev)
1562 {
1563         yaffs_Object *in;
1564         YCHAR *str = NULL;
1565
1566         yaffs_Device *dev = parent->myDev;
1567
1568         /* Check if the entry exists. If it does then fail the call since we don't want a dup.*/
1569         if (yaffs_FindObjectByName(parent, name))
1570                 return NULL;
1571
1572         if (type == YAFFS_OBJECT_TYPE_SYMLINK) {
1573                 str = yaffs_CloneString(aliasString);
1574                 if (!str)
1575                         return NULL;
1576         }
1577
1578         in = yaffs_CreateNewObject(dev, -1, type);
1579
1580         if (!in){
1581                 if(str)
1582                         YFREE(str);
1583                 return NULL;
1584         }
1585
1586
1587
1588
1589
1590         if (in) {
1591                 in->hdrChunk = 0;
1592                 in->valid = 1;
1593                 in->variantType = type;
1594
1595                 in->yst_mode = mode;
1596
1597 #ifdef CONFIG_YAFFS_WINCE
1598                 yfsd_WinFileTimeNow(in->win_atime);
1599                 in->win_ctime[0] = in->win_mtime[0] = in->win_atime[0];
1600                 in->win_ctime[1] = in->win_mtime[1] = in->win_atime[1];
1601
1602 #else
1603                 in->yst_atime = in->yst_mtime = in->yst_ctime = Y_CURRENT_TIME;
1604
1605                 in->yst_rdev = rdev;
1606                 in->yst_uid = uid;
1607                 in->yst_gid = gid;
1608 #endif
1609                 in->nDataChunks = 0;
1610
1611                 yaffs_SetObjectName(in, name);
1612                 in->dirty = 1;
1613
1614                 yaffs_AddObjectToDirectory(parent, in);
1615
1616                 in->myDev = parent->myDev;
1617
1618                 switch (type) {
1619                 case YAFFS_OBJECT_TYPE_SYMLINK:
1620                         in->variant.symLinkVariant.alias = str;
1621                         break;
1622                 case YAFFS_OBJECT_TYPE_HARDLINK:
1623                         in->variant.hardLinkVariant.equivalentObject =
1624                                 equivalentObject;
1625                         in->variant.hardLinkVariant.equivalentObjectId =
1626                                 equivalentObject->objectId;
1627                         ylist_add(&in->hardLinks, &equivalentObject->hardLinks);
1628                         break;
1629                 case YAFFS_OBJECT_TYPE_FILE:
1630                 case YAFFS_OBJECT_TYPE_DIRECTORY:
1631                 case YAFFS_OBJECT_TYPE_SPECIAL:
1632                 case YAFFS_OBJECT_TYPE_UNKNOWN:
1633                         /* do nothing */
1634                         break;
1635                 }
1636
1637                 if (yaffs_UpdateObjectHeader(in, name, 0, 0, 0, NULL) < 0) {
1638                         /* Could not create the object header, fail the creation */
1639                         yaffs_DeleteObject(in);
1640                         in = NULL;
1641                 }
1642
1643                 yaffs_UpdateParent(parent);
1644         }
1645
1646         return in;
1647 }
1648
1649 yaffs_Object *yaffs_MknodFile(yaffs_Object *parent, const YCHAR *name,
1650                         __u32 mode, __u32 uid, __u32 gid)
1651 {
1652         return yaffs_MknodObject(YAFFS_OBJECT_TYPE_FILE, parent, name, mode,
1653                                 uid, gid, NULL, NULL, 0);
1654 }
1655
1656 yaffs_Object *yaffs_MknodDirectory(yaffs_Object *parent, const YCHAR *name,
1657                                 __u32 mode, __u32 uid, __u32 gid)
1658 {
1659         return yaffs_MknodObject(YAFFS_OBJECT_TYPE_DIRECTORY, parent, name,
1660                                  mode, uid, gid, NULL, NULL, 0);
1661 }
1662
1663 yaffs_Object *yaffs_MknodSpecial(yaffs_Object *parent, const YCHAR *name,
1664                                 __u32 mode, __u32 uid, __u32 gid, __u32 rdev)
1665 {
1666         return yaffs_MknodObject(YAFFS_OBJECT_TYPE_SPECIAL, parent, name, mode,
1667                                  uid, gid, NULL, NULL, rdev);
1668 }
1669
1670 yaffs_Object *yaffs_MknodSymLink(yaffs_Object *parent, const YCHAR *name,
1671                                 __u32 mode, __u32 uid, __u32 gid,
1672                                 const YCHAR *alias)
1673 {
1674         return yaffs_MknodObject(YAFFS_OBJECT_TYPE_SYMLINK, parent, name, mode,
1675                                 uid, gid, NULL, alias, 0);
1676 }
1677
1678 /* yaffs_Link returns the object id of the equivalent object.*/
1679 yaffs_Object *yaffs_Link(yaffs_Object *parent, const YCHAR *name,
1680                         yaffs_Object *equivalentObject)
1681 {
1682         /* Get the real object in case we were fed a hard link as an equivalent object */
1683         equivalentObject = yaffs_GetEquivalentObject(equivalentObject);
1684
1685         if (yaffs_MknodObject
1686             (YAFFS_OBJECT_TYPE_HARDLINK, parent, name, 0, 0, 0,
1687              equivalentObject, NULL, 0)) {
1688                 return equivalentObject;
1689         } else {
1690                 return NULL;
1691         }
1692
1693 }
1694
1695 static int yaffs_ChangeObjectName(yaffs_Object *obj, yaffs_Object *newDir,
1696                                 const YCHAR *newName, int force, int shadows)
1697 {
1698         int unlinkOp;
1699         int deleteOp;
1700
1701         yaffs_Object *existingTarget;
1702
1703         if (newDir == NULL)
1704                 newDir = obj->parent;   /* use the old directory */
1705
1706         if (newDir->variantType != YAFFS_OBJECT_TYPE_DIRECTORY) {
1707                 T(YAFFS_TRACE_ALWAYS,
1708                   (TSTR
1709                    ("tragedy: yaffs_ChangeObjectName: newDir is not a directory"
1710                     TENDSTR)));
1711                 YBUG();
1712         }
1713
1714         /* TODO: Do we need this different handling for YAFFS2 and YAFFS1?? */
1715         if (obj->myDev->param.isYaffs2)
1716                 unlinkOp = (newDir == obj->myDev->unlinkedDir);
1717         else
1718                 unlinkOp = (newDir == obj->myDev->unlinkedDir
1719                             && obj->variantType == YAFFS_OBJECT_TYPE_FILE);
1720
1721         deleteOp = (newDir == obj->myDev->deletedDir);
1722
1723         existingTarget = yaffs_FindObjectByName(newDir, newName);
1724
1725         /* If the object is a file going into the unlinked directory,
1726          *   then it is OK to just stuff it in since duplicate names are allowed.
1727          *   else only proceed if the new name does not exist and if we're putting
1728          *   it into a directory.
1729          */
1730         if ((unlinkOp ||
1731              deleteOp ||
1732              force ||
1733              (shadows > 0) ||
1734              !existingTarget) &&
1735             newDir->variantType == YAFFS_OBJECT_TYPE_DIRECTORY) {
1736                 yaffs_SetObjectName(obj, newName);
1737                 obj->dirty = 1;
1738
1739                 yaffs_AddObjectToDirectory(newDir, obj);
1740
1741                 if (unlinkOp)
1742                         obj->unlinked = 1;
1743
1744                 /* If it is a deletion then we mark it as a shrink for gc purposes. */
1745                 if (yaffs_UpdateObjectHeader(obj, newName, 0, deleteOp, shadows, NULL) >= 0)
1746                         return YAFFS_OK;
1747         }
1748
1749         return YAFFS_FAIL;
1750 }
1751
1752 int yaffs_RenameObject(yaffs_Object *oldDir, const YCHAR *oldName,
1753                 yaffs_Object *newDir, const YCHAR *newName)
1754 {
1755         yaffs_Object *obj = NULL;
1756         yaffs_Object *existingTarget = NULL;
1757         int force = 0;
1758         int result;
1759         yaffs_Device *dev;
1760
1761
1762         if (!oldDir || oldDir->variantType != YAFFS_OBJECT_TYPE_DIRECTORY)
1763                 YBUG();
1764         if (!newDir || newDir->variantType != YAFFS_OBJECT_TYPE_DIRECTORY)
1765                 YBUG();
1766
1767         dev = oldDir->myDev;
1768
1769 #ifdef CONFIG_YAFFS_CASE_INSENSITIVE
1770         /* Special case for case insemsitive systems (eg. WinCE).
1771          * While look-up is case insensitive, the name isn't.
1772          * Therefore we might want to change x.txt to X.txt
1773         */
1774         if (oldDir == newDir && yaffs_strcmp(oldName, newName) == 0)
1775                 force = 1;
1776 #endif
1777
1778         if(yaffs_strnlen(newName,YAFFS_MAX_NAME_LENGTH+1) > YAFFS_MAX_NAME_LENGTH)
1779                 /* ENAMETOOLONG */
1780                 return YAFFS_FAIL;
1781
1782         obj = yaffs_FindObjectByName(oldDir, oldName);
1783
1784         if (obj && obj->renameAllowed) {
1785
1786                 /* Now do the handling for an existing target, if there is one */
1787
1788                 existingTarget = yaffs_FindObjectByName(newDir, newName);
1789                 if (existingTarget &&
1790                         existingTarget->variantType == YAFFS_OBJECT_TYPE_DIRECTORY &&
1791                         !ylist_empty(&existingTarget->variant.directoryVariant.children)) {
1792                         /* There is a target that is a non-empty directory, so we fail */
1793                         return YAFFS_FAIL;      /* EEXIST or ENOTEMPTY */
1794                 } else if (existingTarget && existingTarget != obj) {
1795                         /* Nuke the target first, using shadowing,
1796                          * but only if it isn't the same object.
1797                          *
1798                          * Note we must disable gc otherwise it can mess up the shadowing.
1799                          *
1800                          */
1801                         dev->gcDisable=1;
1802                         yaffs_ChangeObjectName(obj, newDir, newName, force,
1803                                                 existingTarget->objectId);
1804                         existingTarget->isShadowed = 1;
1805                         yaffs_UnlinkObject(existingTarget);
1806                         dev->gcDisable=0;
1807                 }
1808
1809                 result = yaffs_ChangeObjectName(obj, newDir, newName, 1, 0);
1810
1811                 yaffs_UpdateParent(oldDir);
1812                 if(newDir != oldDir)
1813                         yaffs_UpdateParent(newDir);
1814
1815                 return result;
1816         }
1817         return YAFFS_FAIL;
1818 }
1819
1820 /*------------------------- Block Management and Page Allocation ----------------*/
1821
1822 static int yaffs_InitialiseBlocks(yaffs_Device *dev)
1823 {
1824         int nBlocks = dev->internalEndBlock - dev->internalStartBlock + 1;
1825
1826         dev->blockInfo = NULL;
1827         dev->chunkBits = NULL;
1828
1829         dev->allocationBlock = -1;      /* force it to get a new one */
1830
1831         /* If the first allocation strategy fails, thry the alternate one */
1832         dev->blockInfo = YMALLOC(nBlocks * sizeof(yaffs_BlockInfo));
1833         if (!dev->blockInfo) {
1834                 dev->blockInfo = YMALLOC_ALT(nBlocks * sizeof(yaffs_BlockInfo));
1835                 dev->blockInfoAlt = 1;
1836         } else
1837                 dev->blockInfoAlt = 0;
1838
1839         if (dev->blockInfo) {
1840                 /* Set up dynamic blockinfo stuff. */
1841                 dev->chunkBitmapStride = (dev->param.nChunksPerBlock + 7) / 8; /* round up bytes */
1842                 dev->chunkBits = YMALLOC(dev->chunkBitmapStride * nBlocks);
1843                 if (!dev->chunkBits) {
1844                         dev->chunkBits = YMALLOC_ALT(dev->chunkBitmapStride * nBlocks);
1845                         dev->chunkBitsAlt = 1;
1846                 } else
1847                         dev->chunkBitsAlt = 0;
1848         }
1849
1850         if (dev->blockInfo && dev->chunkBits) {
1851                 memset(dev->blockInfo, 0, nBlocks * sizeof(yaffs_BlockInfo));
1852                 memset(dev->chunkBits, 0, dev->chunkBitmapStride * nBlocks);
1853                 return YAFFS_OK;
1854         }
1855
1856         return YAFFS_FAIL;
1857 }
1858
1859 static void yaffs_DeinitialiseBlocks(yaffs_Device *dev)
1860 {
1861         if (dev->blockInfoAlt && dev->blockInfo)
1862                 YFREE_ALT(dev->blockInfo);
1863         else if (dev->blockInfo)
1864                 YFREE(dev->blockInfo);
1865
1866         dev->blockInfoAlt = 0;
1867
1868         dev->blockInfo = NULL;
1869
1870         if (dev->chunkBitsAlt && dev->chunkBits)
1871                 YFREE_ALT(dev->chunkBits);
1872         else if (dev->chunkBits)
1873                 YFREE(dev->chunkBits);
1874         dev->chunkBitsAlt = 0;
1875         dev->chunkBits = NULL;
1876 }
1877
1878 void yaffs_BlockBecameDirty(yaffs_Device *dev, int blockNo)
1879 {
1880         yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, blockNo);
1881
1882         int erasedOk = 0;
1883
1884         /* If the block is still healthy erase it and mark as clean.
1885          * If the block has had a data failure, then retire it.
1886          */
1887
1888         T(YAFFS_TRACE_GC | YAFFS_TRACE_ERASE,
1889                 (TSTR("yaffs_BlockBecameDirty block %d state %d %s"TENDSTR),
1890                 blockNo, bi->blockState, (bi->needsRetiring) ? "needs retiring" : ""));
1891
1892         yaffs2_ClearOldestDirtySequence(dev,bi);
1893
1894         bi->blockState = YAFFS_BLOCK_STATE_DIRTY;
1895
1896         /* If this is the block being garbage collected then stop gc'ing this block */
1897         if(blockNo == dev->gcBlock)
1898                 dev->gcBlock = 0;
1899
1900         /* If this block is currently the best candidate for gc then drop as a candidate */
1901         if(blockNo == dev->gcDirtiest){
1902                 dev->gcDirtiest = 0;
1903                 dev->gcPagesInUse = 0;
1904         }
1905
1906         if (!bi->needsRetiring) {
1907                 yaffs2_InvalidateCheckpoint(dev);
1908                 erasedOk = yaffs_EraseBlockInNAND(dev, blockNo);
1909                 if (!erasedOk) {
1910                         dev->nErasureFailures++;
1911                         T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
1912                           (TSTR("**>> Erasure failed %d" TENDSTR), blockNo));
1913                 }
1914         }
1915
1916         if (erasedOk &&
1917             ((yaffs_traceMask & YAFFS_TRACE_ERASE) || !yaffs_SkipVerification(dev))) {
1918                 int i;
1919                 for (i = 0; i < dev->param.nChunksPerBlock; i++) {
1920                         if (!yaffs_CheckChunkErased
1921                             (dev, blockNo * dev->param.nChunksPerBlock + i)) {
1922                                 T(YAFFS_TRACE_ERROR,
1923                                   (TSTR
1924                                    (">>Block %d erasure supposedly OK, but chunk %d not erased"
1925                                     TENDSTR), blockNo, i));
1926                         }
1927                 }
1928         }
1929
1930         if (erasedOk) {
1931                 /* Clean it up... */
1932                 bi->blockState = YAFFS_BLOCK_STATE_EMPTY;
1933                 bi->sequenceNumber = 0;
1934                 dev->nErasedBlocks++;
1935                 bi->pagesInUse = 0;
1936                 bi->softDeletions = 0;
1937                 bi->hasShrinkHeader = 0;
1938                 bi->skipErasedCheck = 1;  /* This is clean, so no need to check */
1939                 bi->gcPrioritise = 0;
1940                 yaffs_ClearChunkBits(dev, blockNo);
1941
1942                 T(YAFFS_TRACE_ERASE,
1943                   (TSTR("Erased block %d" TENDSTR), blockNo));
1944         } else {
1945                 dev->nFreeChunks -= dev->param.nChunksPerBlock; /* We lost a block of free space */
1946
1947                 yaffs_RetireBlock(dev, blockNo);
1948                 T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
1949                   (TSTR("**>> Block %d retired" TENDSTR), blockNo));
1950         }
1951 }
1952
1953 static int yaffs_FindBlockForAllocation(yaffs_Device *dev)
1954 {
1955         int i;
1956
1957         yaffs_BlockInfo *bi;
1958
1959         if (dev->nErasedBlocks < 1) {
1960                 /* Hoosterman we've got a problem.
1961                  * Can't get space to gc
1962                  */
1963                 T(YAFFS_TRACE_ERROR,
1964                   (TSTR("yaffs tragedy: no more erased blocks" TENDSTR)));
1965
1966                 return -1;
1967         }
1968
1969         /* Find an empty block. */
1970
1971         for (i = dev->internalStartBlock; i <= dev->internalEndBlock; i++) {
1972                 dev->allocationBlockFinder++;
1973                 if (dev->allocationBlockFinder < dev->internalStartBlock
1974                     || dev->allocationBlockFinder > dev->internalEndBlock) {
1975                         dev->allocationBlockFinder = dev->internalStartBlock;
1976                 }
1977
1978                 bi = yaffs_GetBlockInfo(dev, dev->allocationBlockFinder);
1979
1980                 if (bi->blockState == YAFFS_BLOCK_STATE_EMPTY) {
1981                         bi->blockState = YAFFS_BLOCK_STATE_ALLOCATING;
1982                         dev->sequenceNumber++;
1983                         bi->sequenceNumber = dev->sequenceNumber;
1984                         dev->nErasedBlocks--;
1985                         T(YAFFS_TRACE_ALLOCATE,
1986                           (TSTR("Allocated block %d, seq  %d, %d left" TENDSTR),
1987                            dev->allocationBlockFinder, dev->sequenceNumber,
1988                            dev->nErasedBlocks));
1989                         return dev->allocationBlockFinder;
1990                 }
1991         }
1992
1993         T(YAFFS_TRACE_ALWAYS,
1994           (TSTR
1995            ("yaffs tragedy: no more erased blocks, but there should have been %d"
1996             TENDSTR), dev->nErasedBlocks));
1997
1998         return -1;
1999 }
2000
2001
2002 /*
2003  * Check if there's space to allocate...
2004  * Thinks.... do we need top make this ths same as yaffs_GetFreeChunks()?
2005  */
2006 int yaffs_CheckSpaceForAllocation(yaffs_Device *dev, int nChunks)
2007 {
2008         int reservedChunks;
2009         int reservedBlocks = dev->param.nReservedBlocks;
2010         int checkpointBlocks;
2011
2012         checkpointBlocks = yaffs2_CalcCheckpointBlocksRequired(dev);
2013
2014         reservedChunks = ((reservedBlocks + checkpointBlocks) * dev->param.nChunksPerBlock);
2015
2016         return (dev->nFreeChunks > (reservedChunks + nChunks));
2017 }
2018
2019 static int yaffs_AllocateChunk(yaffs_Device *dev, int useReserve,
2020                 yaffs_BlockInfo **blockUsedPtr)
2021 {
2022         int retVal;
2023         yaffs_BlockInfo *bi;
2024
2025         if (dev->allocationBlock < 0) {
2026                 /* Get next block to allocate off */
2027                 dev->allocationBlock = yaffs_FindBlockForAllocation(dev);
2028                 dev->allocationPage = 0;
2029         }
2030
2031         if (!useReserve && !yaffs_CheckSpaceForAllocation(dev, 1)) {
2032                 /* Not enough space to allocate unless we're allowed to use the reserve. */
2033                 return -1;
2034         }
2035
2036         if (dev->nErasedBlocks < dev->param.nReservedBlocks
2037                         && dev->allocationPage == 0) {
2038                 T(YAFFS_TRACE_ALLOCATE, (TSTR("Allocating reserve" TENDSTR)));
2039         }
2040
2041         /* Next page please.... */
2042         if (dev->allocationBlock >= 0) {
2043                 bi = yaffs_GetBlockInfo(dev, dev->allocationBlock);
2044
2045                 retVal = (dev->allocationBlock * dev->param.nChunksPerBlock) +
2046                         dev->allocationPage;
2047                 bi->pagesInUse++;
2048                 yaffs_SetChunkBit(dev, dev->allocationBlock,
2049                                 dev->allocationPage);
2050
2051                 dev->allocationPage++;
2052
2053                 dev->nFreeChunks--;
2054
2055                 /* If the block is full set the state to full */
2056                 if (dev->allocationPage >= dev->param.nChunksPerBlock) {
2057                         bi->blockState = YAFFS_BLOCK_STATE_FULL;
2058                         dev->allocationBlock = -1;
2059                 }
2060
2061                 if (blockUsedPtr)
2062                         *blockUsedPtr = bi;
2063
2064                 return retVal;
2065         }
2066
2067         T(YAFFS_TRACE_ERROR,
2068                         (TSTR("!!!!!!!!! Allocator out !!!!!!!!!!!!!!!!!" TENDSTR)));
2069
2070         return -1;
2071 }
2072
2073 static int yaffs_GetErasedChunks(yaffs_Device *dev)
2074 {
2075         int n;
2076
2077         n = dev->nErasedBlocks * dev->param.nChunksPerBlock;
2078
2079         if (dev->allocationBlock > 0)
2080                 n += (dev->param.nChunksPerBlock - dev->allocationPage);
2081
2082         return n;
2083
2084 }
2085
2086 /*
2087  * yaffs_SkipRestOfBlock() skips over the rest of the allocation block
2088  * if we don't want to write to it.
2089  */
2090 void yaffs_SkipRestOfBlock(yaffs_Device *dev)
2091 {
2092         if(dev->allocationBlock > 0){
2093                 yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, dev->allocationBlock);
2094                 if(bi->blockState == YAFFS_BLOCK_STATE_ALLOCATING){
2095                         bi->blockState = YAFFS_BLOCK_STATE_FULL;
2096                         dev->allocationBlock = -1;
2097                 }
2098         }
2099 }
2100
2101
2102 static int yaffs_GarbageCollectBlock(yaffs_Device *dev, int block,
2103                 int wholeBlock)
2104 {
2105         int oldChunk;
2106         int newChunk;
2107         int markNAND;
2108         int retVal = YAFFS_OK;
2109         int i;
2110         int isCheckpointBlock;
2111         int matchingChunk;
2112         int maxCopies;
2113
2114         int chunksBefore = yaffs_GetErasedChunks(dev);
2115         int chunksAfter;
2116
2117         yaffs_ExtendedTags tags;
2118
2119         yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, block);
2120
2121         yaffs_Object *object;
2122
2123         isCheckpointBlock = (bi->blockState == YAFFS_BLOCK_STATE_CHECKPOINT);
2124
2125
2126         T(YAFFS_TRACE_TRACING,
2127                         (TSTR("Collecting block %d, in use %d, shrink %d, wholeBlock %d" TENDSTR),
2128                          block,
2129                          bi->pagesInUse,
2130                          bi->hasShrinkHeader,
2131                          wholeBlock));
2132
2133         /*yaffs_VerifyFreeChunks(dev); */
2134
2135         if(bi->blockState == YAFFS_BLOCK_STATE_FULL)
2136                 bi->blockState = YAFFS_BLOCK_STATE_COLLECTING;
2137
2138         bi->hasShrinkHeader = 0;        /* clear the flag so that the block can erase */
2139
2140         dev->gcDisable = 1;
2141
2142         if (isCheckpointBlock ||
2143                         !yaffs_StillSomeChunkBits(dev, block)) {
2144                 T(YAFFS_TRACE_TRACING,
2145                                 (TSTR
2146                                  ("Collecting block %d that has no chunks in use" TENDSTR),
2147                                  block));
2148                 yaffs_BlockBecameDirty(dev, block);
2149         } else {
2150
2151                 __u8 *buffer = yaffs_GetTempBuffer(dev, __LINE__);
2152
2153                 yaffs_VerifyBlock(dev, bi, block);
2154
2155                 maxCopies = (wholeBlock) ? dev->param.nChunksPerBlock : 5;
2156                 oldChunk = block * dev->param.nChunksPerBlock + dev->gcChunk;
2157
2158                 for (/* init already done */;
2159                      retVal == YAFFS_OK &&
2160                      dev->gcChunk < dev->param.nChunksPerBlock &&
2161                      (bi->blockState == YAFFS_BLOCK_STATE_COLLECTING) &&
2162                      maxCopies > 0;
2163                      dev->gcChunk++, oldChunk++) {
2164                         if (yaffs_CheckChunkBit(dev, block, dev->gcChunk)) {
2165
2166                                 /* This page is in use and might need to be copied off */
2167
2168                                 maxCopies--;
2169
2170                                 markNAND = 1;
2171
2172                                 yaffs_InitialiseTags(&tags);
2173
2174                                 yaffs_ReadChunkWithTagsFromNAND(dev, oldChunk,
2175                                                                 buffer, &tags);
2176
2177                                 object =
2178                                     yaffs_FindObjectByNumber(dev,
2179                                                              tags.objectId);
2180
2181                                 T(YAFFS_TRACE_GC_DETAIL,
2182                                   (TSTR
2183                                    ("Collecting chunk in block %d, %d %d %d " TENDSTR),
2184                                    dev->gcChunk, tags.objectId, tags.chunkId,
2185                                    tags.byteCount));
2186
2187                                 if (object && !yaffs_SkipVerification(dev)) {
2188                                         if (tags.chunkId == 0)
2189                                                 matchingChunk = object->hdrChunk;
2190                                         else if (object->softDeleted)
2191                                                 matchingChunk = oldChunk; /* Defeat the test */
2192                                         else
2193                                                 matchingChunk = yaffs_FindChunkInFile(object, tags.chunkId, NULL);
2194
2195                                         if (oldChunk != matchingChunk)
2196                                                 T(YAFFS_TRACE_ERROR,
2197                                                   (TSTR("gc: page in gc mismatch: %d %d %d %d"TENDSTR),
2198                                                   oldChunk, matchingChunk, tags.objectId, tags.chunkId));
2199
2200                                 }
2201
2202                                 if (!object) {
2203                                         T(YAFFS_TRACE_ERROR,
2204                                           (TSTR
2205                                            ("page %d in gc has no object: %d %d %d "
2206                                             TENDSTR), oldChunk,
2207                                             tags.objectId, tags.chunkId, tags.byteCount));
2208                                 }
2209
2210                                 if (object &&
2211                                     object->deleted &&
2212                                     object->softDeleted &&
2213                                     tags.chunkId != 0) {
2214                                         /* Data chunk in a soft deleted file, throw it away
2215                                          * It's a soft deleted data chunk,
2216                                          * No need to copy this, just forget about it and
2217                                          * fix up the object.
2218                                          */
2219
2220                                         /* Free chunks already includes softdeleted chunks.
2221                                          * How ever this chunk is going to soon be really deleted
2222                                          * which will increment free chunks.
2223                                          * We have to decrement free chunks so this works out properly.
2224                                          */
2225                                         dev->nFreeChunks--;
2226                                         bi->softDeletions--;
2227
2228                                         object->nDataChunks--;
2229
2230                                         if (object->nDataChunks <= 0) {
2231                                                 /* remeber to clean up the object */
2232                                                 dev->gcCleanupList[dev->nCleanups] =
2233                                                     tags.objectId;
2234                                                 dev->nCleanups++;
2235                                         }
2236                                         markNAND = 0;
2237                                 } else if (0) {
2238                                         /* Todo object && object->deleted && object->nDataChunks == 0 */
2239                                         /* Deleted object header with no data chunks.
2240                                          * Can be discarded and the file deleted.
2241                                          */
2242                                         object->hdrChunk = 0;
2243                                         yaffs_FreeTnode(object->myDev,
2244                                                         object->variant.
2245                                                         fileVariant.top);
2246                                         object->variant.fileVariant.top = NULL;
2247                                         yaffs_DoGenericObjectDeletion(object);
2248
2249                                 } else if (object) {
2250                                         /* It's either a data chunk in a live file or
2251                                          * an ObjectHeader, so we're interested in it.
2252                                          * NB Need to keep the ObjectHeaders of deleted files
2253                                          * until the whole file has been deleted off
2254                                          */
2255                                         tags.serialNumber++;
2256
2257                                         dev->nGCCopies++;
2258
2259                                         if (tags.chunkId == 0) {
2260                                                 /* It is an object Id,
2261                                                  * We need to nuke the shrinkheader flags first
2262                                                  * Also need to clean up shadowing.
2263                                                  * We no longer want the shrinkHeader flag since its work is done
2264                                                  * and if it is left in place it will mess up scanning.
2265                                                  */
2266
2267                                                 yaffs_ObjectHeader *oh;
2268                                                 oh = (yaffs_ObjectHeader *)buffer;
2269
2270                                                 oh->isShrink = 0;
2271                                                 tags.extraIsShrinkHeader = 0;
2272
2273                                                 oh->shadowsObject = 0;
2274                                                 oh->inbandShadowsObject = 0;
2275                                                 tags.extraShadows = 0;
2276
2277                                                 /* Update file size */
2278                                                 if(object->variantType == YAFFS_OBJECT_TYPE_FILE){
2279                                                         oh->fileSize = object->variant.fileVariant.fileSize;
2280                                                         tags.extraFileLength = oh->fileSize;
2281                                                 }
2282
2283                                                 yaffs_VerifyObjectHeader(object, oh, &tags, 1);
2284                                                 newChunk =
2285                                                     yaffs_WriteNewChunkWithTagsToNAND(dev,(__u8 *) oh, &tags, 1);
2286                                         } else
2287                                                 newChunk =
2288                                                     yaffs_WriteNewChunkWithTagsToNAND(dev, buffer, &tags, 1);
2289
2290                                         if (newChunk < 0) {
2291                                                 retVal = YAFFS_FAIL;
2292                                         } else {
2293
2294                                                 /* Ok, now fix up the Tnodes etc. */
2295
2296                                                 if (tags.chunkId == 0) {
2297                                                         /* It's a header */
2298                                                         object->hdrChunk =  newChunk;
2299                                                         object->serial =   tags.serialNumber;
2300                                                 } else {
2301                                                         /* It's a data chunk */
2302                                                         int ok;
2303                                                         ok = yaffs_PutChunkIntoFile
2304                                                             (object,
2305                                                              tags.chunkId,
2306                                                              newChunk, 0);
2307                                                 }
2308                                         }
2309                                 }
2310
2311                                 if (retVal == YAFFS_OK)
2312                                         yaffs_DeleteChunk(dev, oldChunk, markNAND, __LINE__);
2313
2314                         }
2315                 }
2316
2317                 yaffs_ReleaseTempBuffer(dev, buffer, __LINE__);
2318
2319
2320
2321         }
2322
2323         yaffs_VerifyCollectedBlock(dev, bi, block);
2324
2325
2326
2327         if (bi->blockState == YAFFS_BLOCK_STATE_COLLECTING) {
2328                 /*
2329                  * The gc did not complete. Set block state back to FULL
2330                  * because checkpointing does not restore gc.
2331                  */
2332                 bi->blockState = YAFFS_BLOCK_STATE_FULL;
2333         } else {
2334                 /* The gc completed. */
2335                 /* Do any required cleanups */
2336                 for (i = 0; i < dev->nCleanups; i++) {
2337                         /* Time to delete the file too */
2338                         object =
2339                             yaffs_FindObjectByNumber(dev,
2340                                                      dev->gcCleanupList[i]);
2341                         if (object) {
2342                                 yaffs_FreeTnode(dev,
2343                                                 object->variant.fileVariant.
2344                                                 top);
2345                                 object->variant.fileVariant.top = NULL;
2346                                 T(YAFFS_TRACE_GC,
2347                                   (TSTR
2348                                    ("yaffs: About to finally delete object %d"
2349                                     TENDSTR), object->objectId));
2350                                 yaffs_DoGenericObjectDeletion(object);
2351                                 object->myDev->nDeletedFiles--;
2352                         }
2353
2354                 }
2355
2356
2357                 chunksAfter = yaffs_GetErasedChunks(dev);
2358                 if (chunksBefore >= chunksAfter) {
2359                         T(YAFFS_TRACE_GC,
2360                           (TSTR
2361                            ("gc did not increase free chunks before %d after %d"
2362                             TENDSTR), chunksBefore, chunksAfter));
2363                 }
2364                 dev->gcBlock = 0;
2365                 dev->gcChunk = 0;
2366                 dev->nCleanups = 0;
2367         }
2368
2369         dev->gcDisable = 0;
2370
2371         return retVal;
2372 }
2373
2374 /*
2375  * FindBlockForgarbageCollection is used to select the dirtiest block (or close enough)
2376  * for garbage collection.
2377  */
2378
2379 static unsigned yaffs_FindBlockForGarbageCollection(yaffs_Device *dev,
2380                                         int aggressive,
2381                                         int background)
2382 {
2383         int i;
2384         int iterations;
2385         unsigned selected = 0;
2386         int prioritised = 0;
2387         int prioritisedExists = 0;
2388         yaffs_BlockInfo *bi;
2389         int threshold;
2390
2391         /* First let's see if we need to grab a prioritised block */
2392         if (dev->hasPendingPrioritisedGCs && !aggressive) {
2393                 dev->gcDirtiest = 0;
2394                 bi = dev->blockInfo;
2395                 for (i = dev->internalStartBlock;
2396                         i <= dev->internalEndBlock && !selected;
2397                         i++) {
2398
2399                         if (bi->gcPrioritise) {
2400                                 prioritisedExists = 1;
2401                                 if (bi->blockState == YAFFS_BLOCK_STATE_FULL &&
2402                                    yaffs2_BlockNotDisqualifiedFromGC(dev, bi)) {
2403                                         selected = i;
2404                                         prioritised = 1;
2405                                 }
2406                         }
2407                         bi++;
2408                 }
2409
2410                 /*
2411                  * If there is a prioritised block and none was selected then
2412                  * this happened because there is at least one old dirty block gumming
2413                  * up the works. Let's gc the oldest dirty block.
2414                  */
2415
2416                 if(prioritisedExists &&
2417                         !selected &&
2418                         dev->oldestDirtyBlock > 0)
2419                         selected = dev->oldestDirtyBlock;
2420
2421                 if (!prioritisedExists) /* None found, so we can clear this */
2422                         dev->hasPendingPrioritisedGCs = 0;
2423         }
2424
2425         /* If we're doing aggressive GC then we are happy to take a less-dirty block, and
2426          * search harder.
2427          * else (we're doing a leasurely gc), then we only bother to do this if the
2428          * block has only a few pages in use.
2429          */
2430
2431         if (!selected){
2432                 int pagesUsed;
2433                 int nBlocks = dev->internalEndBlock - dev->internalStartBlock + 1;
2434                 if (aggressive){
2435                         threshold = dev->param.nChunksPerBlock;
2436                         iterations = nBlocks;
2437                 } else {
2438                         int maxThreshold;
2439
2440                         if(background)
2441                                 maxThreshold = dev->param.nChunksPerBlock/2;
2442                         else
2443                                 maxThreshold = dev->param.nChunksPerBlock/8;
2444
2445                         if(maxThreshold <  YAFFS_GC_PASSIVE_THRESHOLD)
2446                                 maxThreshold = YAFFS_GC_PASSIVE_THRESHOLD;
2447
2448                         threshold = background ?
2449                                 (dev->gcNotDone + 2) * 2 : 0;
2450                         if(threshold <YAFFS_GC_PASSIVE_THRESHOLD)
2451                                 threshold = YAFFS_GC_PASSIVE_THRESHOLD;
2452                         if(threshold > maxThreshold)
2453                                 threshold = maxThreshold;
2454
2455                         iterations = nBlocks / 16 + 1;
2456                         if (iterations > 100)
2457                                 iterations = 100;
2458                 }
2459
2460                 for (i = 0;
2461                         i < iterations &&
2462                         (dev->gcDirtiest < 1 ||
2463                                 dev->gcPagesInUse > YAFFS_GC_GOOD_ENOUGH);
2464                         i++) {
2465                         dev->gcBlockFinder++;
2466                         if (dev->gcBlockFinder < dev->internalStartBlock ||
2467                                 dev->gcBlockFinder > dev->internalEndBlock)
2468                                 dev->gcBlockFinder = dev->internalStartBlock;
2469
2470                         bi = yaffs_GetBlockInfo(dev, dev->gcBlockFinder);
2471
2472                         pagesUsed = bi->pagesInUse - bi->softDeletions;
2473
2474                         if (bi->blockState == YAFFS_BLOCK_STATE_FULL &&
2475                                 pagesUsed < dev->param.nChunksPerBlock &&
2476                                 (dev->gcDirtiest < 1 || pagesUsed < dev->gcPagesInUse) &&
2477                                 yaffs2_BlockNotDisqualifiedFromGC(dev, bi)) {
2478                                 dev->gcDirtiest = dev->gcBlockFinder;
2479                                 dev->gcPagesInUse = pagesUsed;
2480                         }
2481                 }
2482
2483                 if(dev->gcDirtiest > 0 && dev->gcPagesInUse <= threshold)
2484                         selected = dev->gcDirtiest;
2485         }
2486
2487         /*
2488          * If nothing has been selected for a while, try selecting the oldest dirty
2489          * because that's gumming up the works.
2490          */
2491
2492         if(!selected && dev->param.isYaffs2 &&
2493                 dev->gcNotDone >= ( background ? 10 : 20)){
2494                 yaffs2_FindOldestDirtySequence(dev);
2495                 if(dev->oldestDirtyBlock > 0) {
2496                         selected = dev->oldestDirtyBlock;
2497                         dev->gcDirtiest = selected;
2498                         dev->oldestDirtyGCs++;
2499                         bi = yaffs_GetBlockInfo(dev, selected);
2500                         dev->gcPagesInUse =  bi->pagesInUse - bi->softDeletions;
2501                 } else
2502                         dev->gcNotDone = 0;
2503         }
2504
2505         if(selected){
2506                 T(YAFFS_TRACE_GC,
2507                   (TSTR("GC Selected block %d with %d free, prioritised:%d" TENDSTR),
2508                   selected,
2509                   dev->param.nChunksPerBlock - dev->gcPagesInUse,
2510                   prioritised));
2511
2512                 dev->nGCBlocks++;
2513                 if(background)
2514                         dev->backgroundGCs++;
2515
2516                 dev->gcDirtiest = 0;
2517                 dev->gcPagesInUse = 0;
2518                 dev->gcNotDone = 0;
2519                 if(dev->refreshSkip > 0)
2520                         dev->refreshSkip--;
2521         } else{
2522                 dev->gcNotDone++;
2523                 T(YAFFS_TRACE_GC,
2524                   (TSTR("GC none: finder %d skip %d threshold %d dirtiest %d using %d oldest %d%s" TENDSTR),
2525                   dev->gcBlockFinder, dev->gcNotDone,
2526                   threshold,
2527                   dev->gcDirtiest, dev->gcPagesInUse,
2528                   dev->oldestDirtyBlock,
2529                   background ? " bg" : ""));
2530         }
2531
2532         return selected;
2533 }
2534
2535 /* New garbage collector
2536  * If we're very low on erased blocks then we do aggressive garbage collection
2537  * otherwise we do "leasurely" garbage collection.
2538  * Aggressive gc looks further (whole array) and will accept less dirty blocks.
2539  * Passive gc only inspects smaller areas and will only accept more dirty blocks.
2540  *
2541  * The idea is to help clear out space in a more spread-out manner.
2542  * Dunno if it really does anything useful.
2543  */
2544 static int yaffs_CheckGarbageCollection(yaffs_Device *dev, int background)
2545 {
2546         int aggressive = 0;
2547         int gcOk = YAFFS_OK;
2548         int maxTries = 0;
2549         int minErased;
2550         int erasedChunks;
2551         int checkpointBlockAdjust;
2552
2553         if(dev->param.gcControl &&
2554                 (dev->param.gcControl(dev) & 1) == 0)
2555                 return YAFFS_OK;
2556
2557         if (dev->gcDisable) {
2558                 /* Bail out so we don't get recursive gc */
2559                 return YAFFS_OK;
2560         }
2561
2562         /* This loop should pass the first time.
2563          * We'll only see looping here if the collection does not increase space.
2564          */
2565
2566         do {
2567                 maxTries++;
2568
2569                 checkpointBlockAdjust = yaffs2_CalcCheckpointBlocksRequired(dev);
2570
2571                 minErased  = dev->param.nReservedBlocks + checkpointBlockAdjust + 1;
2572                 erasedChunks = dev->nErasedBlocks * dev->param.nChunksPerBlock;
2573
2574                 /* If we need a block soon then do aggressive gc.*/
2575                 if (dev->nErasedBlocks < minErased)
2576                         aggressive = 1;
2577                 else {
2578                         if(!background && erasedChunks > (dev->nFreeChunks / 4))
2579                                 break;
2580
2581                         if(dev->gcSkip > 20)
2582                                 dev->gcSkip = 20;
2583                         if(erasedChunks < dev->nFreeChunks/2 ||
2584                                 dev->gcSkip < 1 ||
2585                                 background)
2586                                 aggressive = 0;
2587                         else {
2588                                 dev->gcSkip--;
2589                                 break;
2590                         }
2591                 }
2592
2593                 dev->gcSkip = 5;
2594
2595                 /* If we don't already have a block being gc'd then see if we should start another */
2596
2597                 if (dev->gcBlock < 1 && !aggressive) {
2598                         dev->gcBlock = yaffs2_FindRefreshBlock(dev);
2599                         dev->gcChunk = 0;
2600                         dev->nCleanups=0;
2601                 }
2602                 if (dev->gcBlock < 1) {
2603                         dev->gcBlock = yaffs_FindBlockForGarbageCollection(dev, aggressive, background);
2604                         dev->gcChunk = 0;
2605                         dev->nCleanups=0;
2606                 }
2607
2608                 if (dev->gcBlock > 0) {
2609                         dev->allGCs++;
2610                         if (!aggressive)
2611                                 dev->passiveGCs++;
2612
2613                         T(YAFFS_TRACE_GC,
2614                           (TSTR
2615                            ("yaffs: GC erasedBlocks %d aggressive %d" TENDSTR),
2616                            dev->nErasedBlocks, aggressive));
2617
2618                         gcOk = yaffs_GarbageCollectBlock(dev, dev->gcBlock, aggressive);
2619                 }
2620
2621                 if (dev->nErasedBlocks < (dev->param.nReservedBlocks) && dev->gcBlock > 0) {
2622                         T(YAFFS_TRACE_GC,
2623                           (TSTR
2624                            ("yaffs: GC !!!no reclaim!!! erasedBlocks %d after try %d block %d"
2625                             TENDSTR), dev->nErasedBlocks, maxTries, dev->gcBlock));
2626                 }
2627         } while ((dev->nErasedBlocks < dev->param.nReservedBlocks) &&
2628                  (dev->gcBlock > 0) &&
2629                  (maxTries < 2));
2630
2631         return aggressive ? gcOk : YAFFS_OK;
2632 }
2633
2634 /*
2635  * yaffs_BackgroundGarbageCollect()
2636  * Garbage collects. Intended to be called from a background thread.
2637  * Returns non-zero if at least half the free chunks are erased.
2638  */
2639 int yaffs_BackgroundGarbageCollect(yaffs_Device *dev, unsigned urgency)
2640 {
2641         int erasedChunks = dev->nErasedBlocks * dev->param.nChunksPerBlock;
2642
2643         T(YAFFS_TRACE_BACKGROUND, (TSTR("Background gc %u" TENDSTR),urgency));
2644
2645         yaffs_CheckGarbageCollection(dev, 1);
2646         return erasedChunks > dev->nFreeChunks/2;
2647 }
2648
2649 /*-------------------------  TAGS --------------------------------*/
2650
2651 static int yaffs_TagsMatch(const yaffs_ExtendedTags *tags, int objectId,
2652                            int chunkInObject)
2653 {
2654         return (tags->chunkId == chunkInObject &&
2655                 tags->objectId == objectId && !tags->chunkDeleted) ? 1 : 0;
2656
2657 }
2658
2659
2660 /*-------------------- Data file manipulation -----------------*/
2661
2662 static int yaffs_FindChunkInFile(yaffs_Object *in, int chunkInInode,
2663                                  yaffs_ExtendedTags *tags)
2664 {
2665         /*Get the Tnode, then get the level 0 offset chunk offset */
2666         yaffs_Tnode *tn;
2667         int theChunk = -1;
2668         yaffs_ExtendedTags localTags;
2669         int retVal = -1;
2670
2671         yaffs_Device *dev = in->myDev;
2672
2673         if (!tags) {
2674                 /* Passed a NULL, so use our own tags space */
2675                 tags = &localTags;
2676         }
2677
2678         tn = yaffs_FindLevel0Tnode(dev, &in->variant.fileVariant, chunkInInode);
2679
2680         if (tn) {
2681                 theChunk = yaffs_GetChunkGroupBase(dev, tn, chunkInInode);
2682
2683                 retVal =
2684                     yaffs_FindChunkInGroup(dev, theChunk, tags, in->objectId,
2685                                            chunkInInode);
2686         }
2687         return retVal;
2688 }
2689
2690 static int yaffs_FindAndDeleteChunkInFile(yaffs_Object *in, int chunkInInode,
2691                                           yaffs_ExtendedTags *tags)
2692 {
2693         /* Get the Tnode, then get the level 0 offset chunk offset */
2694         yaffs_Tnode *tn;
2695         int theChunk = -1;
2696         yaffs_ExtendedTags localTags;
2697
2698         yaffs_Device *dev = in->myDev;
2699         int retVal = -1;
2700
2701         if (!tags) {
2702                 /* Passed a NULL, so use our own tags space */
2703                 tags = &localTags;
2704         }
2705
2706         tn = yaffs_FindLevel0Tnode(dev, &in->variant.fileVariant, chunkInInode);
2707
2708         if (tn) {
2709
2710                 theChunk = yaffs_GetChunkGroupBase(dev, tn, chunkInInode);
2711
2712                 retVal =
2713                     yaffs_FindChunkInGroup(dev, theChunk, tags, in->objectId,
2714                                            chunkInInode);
2715
2716                 /* Delete the entry in the filestructure (if found) */
2717                 if (retVal != -1)
2718                         yaffs_LoadLevel0Tnode(dev, tn, chunkInInode, 0);
2719         }
2720
2721         return retVal;
2722 }
2723
2724
2725 int yaffs_PutChunkIntoFile(yaffs_Object *in, int chunkInInode,
2726                                 int chunkInNAND, int inScan)
2727 {
2728         /* NB inScan is zero unless scanning.
2729          * For forward scanning, inScan is > 0;
2730          * for backward scanning inScan is < 0
2731          *
2732          * chunkInNAND = 0 is a dummy insert to make sure the tnodes are there.
2733          */
2734
2735         yaffs_Tnode *tn;
2736         yaffs_Device *dev = in->myDev;
2737         int existingChunk;
2738         yaffs_ExtendedTags existingTags;
2739         yaffs_ExtendedTags newTags;
2740         unsigned existingSerial, newSerial;
2741
2742         if (in->variantType != YAFFS_OBJECT_TYPE_FILE) {
2743                 /* Just ignore an attempt at putting a chunk into a non-file during scanning
2744                  * If it is not during Scanning then something went wrong!
2745                  */
2746                 if (!inScan) {
2747                         T(YAFFS_TRACE_ERROR,
2748                           (TSTR
2749                            ("yaffs tragedy:attempt to put data chunk into a non-file"
2750                             TENDSTR)));
2751                         YBUG();
2752                 }
2753
2754                 yaffs_DeleteChunk(dev, chunkInNAND, 1, __LINE__);
2755                 return YAFFS_OK;
2756         }
2757
2758         tn = yaffs_AddOrFindLevel0Tnode(dev,
2759                                         &in->variant.fileVariant,
2760                                         chunkInInode,
2761                                         NULL);
2762         if (!tn)
2763                 return YAFFS_FAIL;
2764
2765         if(!chunkInNAND)
2766                 /* Dummy insert, bail now */
2767                 return YAFFS_OK;
2768
2769         existingChunk = yaffs_GetChunkGroupBase(dev, tn, chunkInInode);
2770
2771         if (inScan != 0) {
2772                 /* If we're scanning then we need to test for duplicates
2773                  * NB This does not need to be efficient since it should only ever
2774                  * happen when the power fails during a write, then only one
2775                  * chunk should ever be affected.
2776                  *
2777                  * Correction for YAFFS2: This could happen quite a lot and we need to think about efficiency! TODO
2778                  * Update: For backward scanning we don't need to re-read tags so this is quite cheap.
2779                  */
2780
2781                 if (existingChunk > 0) {
2782                         /* NB Right now existing chunk will not be real chunkId if the chunk group size > 1
2783                          *    thus we have to do a FindChunkInFile to get the real chunk id.
2784                          *
2785                          * We have a duplicate now we need to decide which one to use:
2786                          *
2787                          * Backwards scanning YAFFS2: The old one is what we use, dump the new one.
2788                          * Forward scanning YAFFS2: The new one is what we use, dump the old one.
2789                          * YAFFS1: Get both sets of tags and compare serial numbers.
2790                          */
2791
2792                         if (inScan > 0) {
2793                                 /* Only do this for forward scanning */
2794                                 yaffs_ReadChunkWithTagsFromNAND(dev,
2795                                                                 chunkInNAND,
2796                                                                 NULL, &newTags);
2797
2798                                 /* Do a proper find */
2799                                 existingChunk =
2800                                     yaffs_FindChunkInFile(in, chunkInInode,
2801                                                           &existingTags);
2802                         }
2803
2804                         if (existingChunk <= 0) {
2805                                 /*Hoosterman - how did this happen? */
2806
2807                                 T(YAFFS_TRACE_ERROR,
2808                                   (TSTR
2809                                    ("yaffs tragedy: existing chunk < 0 in scan"
2810                                     TENDSTR)));
2811
2812                         }
2813
2814                         /* NB The deleted flags should be false, otherwise the chunks will
2815                          * not be loaded during a scan
2816                          */
2817
2818                         if (inScan > 0) {
2819                                 newSerial = newTags.serialNumber;
2820                                 existingSerial = existingTags.serialNumber;
2821                         }
2822
2823                         if ((inScan > 0) &&
2824                             (existingChunk <= 0 ||
2825                              ((existingSerial + 1) & 3) == newSerial)) {
2826                                 /* Forward scanning.
2827                                  * Use new
2828                                  * Delete the old one and drop through to update the tnode
2829                                  */
2830                                 yaffs_DeleteChunk(dev, existingChunk, 1,
2831                                                   __LINE__);
2832                         } else {
2833                                 /* Backward scanning or we want to use the existing one
2834                                  * Use existing.
2835                                  * Delete the new one and return early so that the tnode isn't changed
2836                                  */
2837                                 yaffs_DeleteChunk(dev, chunkInNAND, 1,
2838                                                   __LINE__);
2839                                 return YAFFS_OK;
2840                         }
2841                 }
2842
2843         }
2844
2845         if (existingChunk == 0)
2846                 in->nDataChunks++;
2847
2848         yaffs_LoadLevel0Tnode(dev, tn, chunkInInode, chunkInNAND);
2849
2850         return YAFFS_OK;
2851 }
2852
2853 static int yaffs_ReadChunkDataFromObject(yaffs_Object *in, int chunkInInode,
2854                                         __u8 *buffer)
2855 {
2856         int chunkInNAND = yaffs_FindChunkInFile(in, chunkInInode, NULL);
2857
2858         if (chunkInNAND >= 0)
2859                 return yaffs_ReadChunkWithTagsFromNAND(in->myDev, chunkInNAND,
2860                                                 buffer, NULL);
2861         else {
2862                 T(YAFFS_TRACE_NANDACCESS,
2863                   (TSTR("Chunk %d not found zero instead" TENDSTR),
2864                    chunkInNAND));
2865                 /* get sane (zero) data if you read a hole */
2866                 memset(buffer, 0, in->myDev->nDataBytesPerChunk);
2867                 return 0;
2868         }
2869
2870 }
2871
2872 void yaffs_DeleteChunk(yaffs_Device *dev, int chunkId, int markNAND, int lyn)
2873 {
2874         int block;
2875         int page;
2876         yaffs_ExtendedTags tags;
2877         yaffs_BlockInfo *bi;
2878
2879         if (chunkId <= 0)
2880                 return;
2881
2882         dev->nDeletions++;
2883         block = chunkId / dev->param.nChunksPerBlock;
2884         page = chunkId % dev->param.nChunksPerBlock;
2885
2886
2887         if (!yaffs_CheckChunkBit(dev, block, page))
2888                 T(YAFFS_TRACE_VERIFY,
2889                         (TSTR("Deleting invalid chunk %d"TENDSTR),
2890                          chunkId));
2891
2892         bi = yaffs_GetBlockInfo(dev, block);
2893
2894         yaffs2_UpdateOldestDirtySequence(dev, block, bi);
2895
2896         T(YAFFS_TRACE_DELETION,
2897           (TSTR("line %d delete of chunk %d" TENDSTR), lyn, chunkId));
2898
2899         if (!dev->param.isYaffs2 && markNAND &&
2900             bi->blockState != YAFFS_BLOCK_STATE_COLLECTING) {
2901
2902                 yaffs_InitialiseTags(&tags);
2903
2904                 tags.chunkDeleted = 1;
2905
2906                 yaffs_WriteChunkWithTagsToNAND(dev, chunkId, NULL, &tags);
2907                 yaffs_HandleUpdateChunk(dev, chunkId, &tags);
2908         } else {
2909                 dev->nUnmarkedDeletions++;
2910         }
2911
2912         /* Pull out of the management area.
2913          * If the whole block became dirty, this will kick off an erasure.
2914          */
2915         if (bi->blockState == YAFFS_BLOCK_STATE_ALLOCATING ||
2916             bi->blockState == YAFFS_BLOCK_STATE_FULL ||
2917             bi->blockState == YAFFS_BLOCK_STATE_NEEDS_SCANNING ||
2918             bi->blockState == YAFFS_BLOCK_STATE_COLLECTING) {
2919                 dev->nFreeChunks++;
2920
2921                 yaffs_ClearChunkBit(dev, block, page);
2922
2923                 bi->pagesInUse--;
2924
2925                 if (bi->pagesInUse == 0 &&
2926                     !bi->hasShrinkHeader &&
2927                     bi->blockState != YAFFS_BLOCK_STATE_ALLOCATING &&
2928                     bi->blockState != YAFFS_BLOCK_STATE_NEEDS_SCANNING) {
2929                         yaffs_BlockBecameDirty(dev, block);
2930                 }
2931
2932         }
2933
2934 }
2935
2936 static int yaffs_WriteChunkDataToObject(yaffs_Object *in, int chunkInInode,
2937                                         const __u8 *buffer, int nBytes,
2938                                         int useReserve)
2939 {
2940         /* Find old chunk Need to do this to get serial number
2941          * Write new one and patch into tree.
2942          * Invalidate old tags.
2943          */
2944
2945         int prevChunkId;
2946         yaffs_ExtendedTags prevTags;
2947
2948         int newChunkId;
2949         yaffs_ExtendedTags newTags;
2950
2951         yaffs_Device *dev = in->myDev;
2952
2953         yaffs_CheckGarbageCollection(dev,0);
2954
2955         /* Get the previous chunk at this location in the file if it exists.
2956          * If it does not exist then put a zero into the tree. This creates
2957          * the tnode now, rather than later when it is harder to clean up.
2958          */
2959         prevChunkId = yaffs_FindChunkInFile(in, chunkInInode, &prevTags);
2960         if(prevChunkId < 1 &&
2961                 !yaffs_PutChunkIntoFile(in, chunkInInode, 0, 0))
2962                 return 0;
2963
2964         /* Set up new tags */
2965         yaffs_InitialiseTags(&newTags);
2966
2967         newTags.chunkId = chunkInInode;
2968         newTags.objectId = in->objectId;
2969         newTags.serialNumber =
2970             (prevChunkId > 0) ? prevTags.serialNumber + 1 : 1;
2971         newTags.byteCount = nBytes;
2972
2973         if (nBytes < 1 || nBytes > dev->param.totalBytesPerChunk) {
2974                 T(YAFFS_TRACE_ERROR,
2975                 (TSTR("Writing %d bytes to chunk!!!!!!!!!" TENDSTR), nBytes));
2976                 YBUG();
2977         }
2978
2979
2980         newChunkId =
2981             yaffs_WriteNewChunkWithTagsToNAND(dev, buffer, &newTags,
2982                                               useReserve);
2983
2984         if (newChunkId > 0) {
2985                 yaffs_PutChunkIntoFile(in, chunkInInode, newChunkId, 0);
2986
2987                 if (prevChunkId > 0)
2988                         yaffs_DeleteChunk(dev, prevChunkId, 1, __LINE__);
2989
2990                 yaffs_VerifyFileSanity(in);
2991         }
2992         return newChunkId;
2993
2994 }
2995
2996 /* UpdateObjectHeader updates the header on NAND for an object.
2997  * If name is not NULL, then that new name is used.
2998  */
2999 int yaffs_UpdateObjectHeader(yaffs_Object *in, const YCHAR *name, int force,
3000                              int isShrink, int shadows, yaffs_XAttrMod *xmod)
3001 {
3002
3003         yaffs_BlockInfo *bi;
3004
3005         yaffs_Device *dev = in->myDev;
3006
3007         int prevChunkId;
3008         int retVal = 0;
3009         int result = 0;
3010
3011         int newChunkId;
3012         yaffs_ExtendedTags newTags;
3013         yaffs_ExtendedTags oldTags;
3014         YCHAR *alias = NULL;
3015
3016         __u8 *buffer = NULL;
3017         YCHAR oldName[YAFFS_MAX_NAME_LENGTH + 1];
3018
3019         yaffs_ObjectHeader *oh = NULL;
3020
3021         yaffs_strcpy(oldName, _Y("silly old name"));
3022
3023
3024         if (!in->fake ||
3025                 in == dev->rootDir || /* The rootDir should also be saved */
3026                 force  || xmod) {
3027
3028                 yaffs_CheckGarbageCollection(dev,0);
3029                 yaffs_CheckObjectDetailsLoaded(in);
3030
3031                 buffer = yaffs_GetTempBuffer(in->myDev, __LINE__);
3032                 oh = (yaffs_ObjectHeader *) buffer;
3033
3034                 prevChunkId = in->hdrChunk;
3035
3036                 if (prevChunkId > 0) {
3037                         result = yaffs_ReadChunkWithTagsFromNAND(dev, prevChunkId,
3038                                                         buffer, &oldTags);
3039
3040                         yaffs_VerifyObjectHeader(in, oh, &oldTags, 0);
3041
3042                         memcpy(oldName, oh->name, sizeof(oh->name));
3043                         memset(buffer, 0xFF, sizeof(yaffs_ObjectHeader));
3044                 } else
3045                         memset(buffer, 0xFF, dev->nDataBytesPerChunk);
3046
3047                 oh->type = in->variantType;
3048                 oh->yst_mode = in->yst_mode;
3049                 oh->shadowsObject = oh->inbandShadowsObject = shadows;
3050
3051 #ifdef CONFIG_YAFFS_WINCE
3052                 oh->win_atime[0] = in->win_atime[0];
3053                 oh->win_ctime[0] = in->win_ctime[0];
3054                 oh->win_mtime[0] = in->win_mtime[0];
3055                 oh->win_atime[1] = in->win_atime[1];
3056                 oh->win_ctime[1] = in->win_ctime[1];
3057                 oh->win_mtime[1] = in->win_mtime[1];
3058 #else
3059                 oh->yst_uid = in->yst_uid;
3060                 oh->yst_gid = in->yst_gid;
3061                 oh->yst_atime = in->yst_atime;
3062                 oh->yst_mtime = in->yst_mtime;
3063                 oh->yst_ctime = in->yst_ctime;
3064                 oh->yst_rdev = in->yst_rdev;
3065 #endif
3066                 if (in->parent)
3067                         oh->parentObjectId = in->parent->objectId;
3068                 else
3069                         oh->parentObjectId = 0;
3070
3071                 if (name && *name) {
3072                         memset(oh->name, 0, sizeof(oh->name));
3073                         yaffs_LoadObjectHeaderFromName(dev,oh->name,name);
3074                 } else if (prevChunkId > 0)
3075                         memcpy(oh->name, oldName, sizeof(oh->name));
3076                 else
3077                         memset(oh->name, 0, sizeof(oh->name));
3078
3079                 oh->isShrink = isShrink;
3080
3081                 switch (in->variantType) {
3082                 case YAFFS_OBJECT_TYPE_UNKNOWN:
3083                         /* Should not happen */
3084                         break;
3085                 case YAFFS_OBJECT_TYPE_FILE:
3086                         oh->fileSize =
3087                             (oh->parentObjectId == YAFFS_OBJECTID_DELETED
3088                              || oh->parentObjectId ==
3089                              YAFFS_OBJECTID_UNLINKED) ? 0 : in->variant.
3090                             fileVariant.fileSize;
3091                         break;
3092                 case YAFFS_OBJECT_TYPE_HARDLINK:
3093                         oh->equivalentObjectId =
3094                             in->variant.hardLinkVariant.equivalentObjectId;
3095                         break;
3096                 case YAFFS_OBJECT_TYPE_SPECIAL:
3097                         /* Do nothing */
3098                         break;
3099                 case YAFFS_OBJECT_TYPE_DIRECTORY:
3100                         /* Do nothing */
3101                         break;
3102                 case YAFFS_OBJECT_TYPE_SYMLINK:
3103                         alias = in->variant.symLinkVariant.alias;
3104                         if(!alias)
3105                                 alias = _Y("no alias");
3106                         yaffs_strncpy(oh->alias,
3107                                         alias,
3108                                       YAFFS_MAX_ALIAS_LENGTH);
3109                         oh->alias[YAFFS_MAX_ALIAS_LENGTH] = 0;
3110                         break;
3111                 }
3112
3113                 /* process any xattrib modifications */
3114                 if(xmod)
3115                         yaffs_ApplyXMod(dev, (char *)buffer, xmod);
3116
3117
3118                 /* Tags */
3119                 yaffs_InitialiseTags(&newTags);
3120                 in->serial++;
3121                 newTags.chunkId = 0;
3122                 newTags.objectId = in->objectId;
3123                 newTags.serialNumber = in->serial;
3124
3125                 /* Add extra info for file header */
3126
3127                 newTags.extraHeaderInfoAvailable = 1;
3128                 newTags.extraParentObjectId = oh->parentObjectId;
3129                 newTags.extraFileLength = oh->fileSize;
3130                 newTags.extraIsShrinkHeader = oh->isShrink;
3131                 newTags.extraEquivalentObjectId = oh->equivalentObjectId;
3132                 newTags.extraShadows = (oh->shadowsObject > 0) ? 1 : 0;
3133                 newTags.extraObjectType = in->variantType;
3134
3135                 yaffs_VerifyObjectHeader(in, oh, &newTags, 1);
3136
3137                 /* Create new chunk in NAND */
3138                 newChunkId =
3139                     yaffs_WriteNewChunkWithTagsToNAND(dev, buffer, &newTags,
3140                                                       (prevChunkId > 0) ? 1 : 0);
3141
3142                 if (newChunkId >= 0) {
3143
3144                         in->hdrChunk = newChunkId;
3145
3146                         if (prevChunkId > 0) {
3147                                 yaffs_DeleteChunk(dev, prevChunkId, 1,
3148                                                   __LINE__);
3149                         }
3150
3151                         if (!yaffs_ObjectHasCachedWriteData(in))
3152                                 in->dirty = 0;
3153
3154                         /* If this was a shrink, then mark the block that the chunk lives on */
3155                         if (isShrink) {
3156                                 bi = yaffs_GetBlockInfo(in->myDev,
3157                                         newChunkId / in->myDev->param.nChunksPerBlock);
3158                                 bi->hasShrinkHeader = 1;
3159                         }
3160
3161                 }
3162
3163                 retVal = newChunkId;
3164
3165         }
3166
3167         if (buffer)
3168                 yaffs_ReleaseTempBuffer(dev, buffer, __LINE__);
3169
3170         return retVal;
3171 }
3172
3173 /*------------------------ Short Operations Cache ----------------------------------------
3174  *   In many situations where there is no high level buffering (eg WinCE) a lot of
3175  *   reads might be short sequential reads, and a lot of writes may be short
3176  *   sequential writes. eg. scanning/writing a jpeg file.
3177  *   In these cases, a short read/write cache can provide a huge perfomance benefit
3178  *   with dumb-as-a-rock code.
3179  *   In Linux, the page cache provides read buffering aand the short op cache provides write
3180  *   buffering.
3181  *
3182  *   There are a limited number (~10) of cache chunks per device so that we don't
3183  *   need a very intelligent search.
3184  */
3185
3186 static int yaffs_ObjectHasCachedWriteData(yaffs_Object *obj)
3187 {
3188         yaffs_Device *dev = obj->myDev;
3189         int i;
3190         yaffs_ChunkCache *cache;
3191         int nCaches = obj->myDev->param.nShortOpCaches;
3192
3193         for (i = 0; i < nCaches; i++) {
3194                 cache = &dev->srCache[i];
3195                 if (cache->object == obj &&
3196                     cache->dirty)
3197                         return 1;
3198         }
3199
3200         return 0;
3201 }
3202
3203
3204 static void yaffs_FlushFilesChunkCache(yaffs_Object *obj)
3205 {
3206         yaffs_Device *dev = obj->myDev;
3207         int lowest = -99;       /* Stop compiler whining. */
3208         int i;
3209         yaffs_ChunkCache *cache;
3210         int chunkWritten = 0;
3211         int nCaches = obj->myDev->param.nShortOpCaches;
3212
3213         if (nCaches > 0) {
3214                 do {
3215                         cache = NULL;
3216
3217                         /* Find the dirty cache for this object with the lowest chunk id. */
3218                         for (i = 0; i < nCaches; i++) {
3219                                 if (dev->srCache[i].object == obj &&
3220                                     dev->srCache[i].dirty) {
3221                                         if (!cache
3222                                             || dev->srCache[i].chunkId <
3223                                             lowest) {
3224                                                 cache = &dev->srCache[i];
3225                                                 lowest = cache->chunkId;
3226                                         }
3227                                 }
3228                         }
3229
3230                         if (cache && !cache->locked) {
3231                                 /* Write it out and free it up */
3232
3233                                 chunkWritten =
3234                                     yaffs_WriteChunkDataToObject(cache->object,
3235                                                                  cache->chunkId,
3236                                                                  cache->data,
3237                                                                  cache->nBytes,
3238                                                                  1);
3239                                 cache->dirty = 0;
3240                                 cache->object = NULL;
3241                         }
3242
3243                 } while (cache && chunkWritten > 0);
3244
3245                 if (cache) {
3246                         /* Hoosterman, disk full while writing cache out. */
3247                         T(YAFFS_TRACE_ERROR,
3248                           (TSTR("yaffs tragedy: no space during cache write" TENDSTR)));
3249
3250                 }
3251         }
3252
3253 }
3254
3255 /*yaffs_FlushEntireDeviceCache(dev)
3256  *
3257  *
3258  */
3259
3260 void yaffs_FlushEntireDeviceCache(yaffs_Device *dev)
3261 {
3262         yaffs_Object *obj;
3263         int nCaches = dev->param.nShortOpCaches;
3264         int i;
3265
3266         /* Find a dirty object in the cache and flush it...
3267          * until there are no further dirty objects.
3268          */
3269         do {
3270                 obj = NULL;
3271                 for (i = 0; i < nCaches && !obj; i++) {
3272                         if (dev->srCache[i].object &&
3273                             dev->srCache[i].dirty)
3274                                 obj = dev->srCache[i].object;
3275
3276                 }
3277                 if (obj)
3278                         yaffs_FlushFilesChunkCache(obj);
3279
3280         } while (obj);
3281
3282 }
3283
3284
3285 /* Grab us a cache chunk for use.
3286  * First look for an empty one.
3287  * Then look for the least recently used non-dirty one.
3288  * Then look for the least recently used dirty one...., flush and look again.
3289  */
3290 static yaffs_ChunkCache *yaffs_GrabChunkCacheWorker(yaffs_Device *dev)
3291 {
3292         int i;
3293
3294         if (dev->param.nShortOpCaches > 0) {
3295                 for (i = 0; i < dev->param.nShortOpCaches; i++) {
3296                         if (!dev->srCache[i].object)
3297                                 return &dev->srCache[i];
3298                 }
3299         }
3300
3301         return NULL;
3302 }
3303
3304 static yaffs_ChunkCache *yaffs_GrabChunkCache(yaffs_Device *dev)
3305 {
3306         yaffs_ChunkCache *cache;
3307         yaffs_Object *theObj;
3308         int usage;
3309         int i;
3310         int pushout;
3311
3312         if (dev->param.nShortOpCaches > 0) {
3313                 /* Try find a non-dirty one... */
3314
3315                 cache = yaffs_GrabChunkCacheWorker(dev);
3316
3317                 if (!cache) {
3318                         /* They were all dirty, find the last recently used object and flush
3319                          * its cache, then  find again.
3320                          * NB what's here is not very accurate, we actually flush the object
3321                          * the last recently used page.
3322                          */
3323
3324                         /* With locking we can't assume we can use entry zero */
3325
3326                         theObj = NULL;
3327                         usage = -1;
3328                         cache = NULL;
3329                         pushout = -1;
3330
3331                         for (i = 0; i < dev->param.nShortOpCaches; i++) {
3332                                 if (dev->srCache[i].object &&
3333                                     !dev->srCache[i].locked &&
3334                                     (dev->srCache[i].lastUse < usage || !cache)) {
3335                                         usage = dev->srCache[i].lastUse;
3336                                         theObj = dev->srCache[i].object;
3337                                         cache = &dev->srCache[i];
3338                                         pushout = i;
3339                                 }
3340                         }
3341
3342                         if (!cache || cache->dirty) {
3343                                 /* Flush and try again */
3344                                 yaffs_FlushFilesChunkCache(theObj);
3345                                 cache = yaffs_GrabChunkCacheWorker(dev);
3346                         }
3347
3348                 }
3349                 return cache;
3350         } else
3351                 return NULL;
3352
3353 }
3354
3355 /* Find a cached chunk */
3356 static yaffs_ChunkCache *yaffs_FindChunkCache(const yaffs_Object *obj,
3357                                               int chunkId)
3358 {
3359         yaffs_Device *dev = obj->myDev;
3360         int i;
3361         if (dev->param.nShortOpCaches > 0) {
3362                 for (i = 0; i < dev->param.nShortOpCaches; i++) {
3363                         if (dev->srCache[i].object == obj &&
3364                             dev->srCache[i].chunkId == chunkId) {
3365                                 dev->cacheHits++;
3366
3367                                 return &dev->srCache[i];
3368                         }
3369                 }
3370         }
3371         return NULL;
3372 }
3373
3374 /* Mark the chunk for the least recently used algorithym */
3375 static void yaffs_UseChunkCache(yaffs_Device *dev, yaffs_ChunkCache *cache,
3376                                 int isAWrite)
3377 {
3378
3379         if (dev->param.nShortOpCaches > 0) {
3380                 if (dev->srLastUse < 0 || dev->srLastUse > 100000000) {
3381                         /* Reset the cache usages */
3382                         int i;
3383                         for (i = 1; i < dev->param.nShortOpCaches; i++)
3384                                 dev->srCache[i].lastUse = 0;
3385
3386                         dev->srLastUse = 0;
3387                 }
3388
3389                 dev->srLastUse++;
3390
3391                 cache->lastUse = dev->srLastUse;
3392
3393                 if (isAWrite)
3394                         cache->dirty = 1;
3395         }
3396 }
3397
3398 /* Invalidate a single cache page.
3399  * Do this when a whole page gets written,
3400  * ie the short cache for this page is no longer valid.
3401  */
3402 static void yaffs_InvalidateChunkCache(yaffs_Object *object, int chunkId)
3403 {
3404         if (object->myDev->param.nShortOpCaches > 0) {
3405                 yaffs_ChunkCache *cache = yaffs_FindChunkCache(object, chunkId);
3406
3407                 if (cache)
3408                         cache->object = NULL;
3409         }
3410 }
3411
3412 /* Invalidate all the cache pages associated with this object
3413  * Do this whenever ther file is deleted or resized.
3414  */
3415 static void yaffs_InvalidateWholeChunkCache(yaffs_Object *in)
3416 {
3417         int i;
3418         yaffs_Device *dev = in->myDev;
3419
3420         if (dev->param.nShortOpCaches > 0) {
3421                 /* Invalidate it. */
3422                 for (i = 0; i < dev->param.nShortOpCaches; i++) {
3423                         if (dev->srCache[i].object == in)
3424                                 dev->srCache[i].object = NULL;
3425                 }
3426         }
3427 }
3428
3429
3430 /*--------------------- File read/write ------------------------
3431  * Read and write have very similar structures.
3432  * In general the read/write has three parts to it
3433  * An incomplete chunk to start with (if the read/write is not chunk-aligned)
3434  * Some complete chunks
3435  * An incomplete chunk to end off with
3436  *
3437  * Curve-balls: the first chunk might also be the last chunk.
3438  */
3439
3440 int yaffs_ReadDataFromFile(yaffs_Object *in, __u8 *buffer, loff_t offset,
3441                         int nBytes)
3442 {
3443
3444         int chunk;
3445         __u32 start;
3446         int nToCopy;
3447         int n = nBytes;
3448         int nDone = 0;
3449         yaffs_ChunkCache *cache;
3450
3451         yaffs_Device *dev;
3452
3453         dev = in->myDev;
3454
3455         while (n > 0) {
3456                 /* chunk = offset / dev->nDataBytesPerChunk + 1; */
3457                 /* start = offset % dev->nDataBytesPerChunk; */
3458                 yaffs_AddrToChunk(dev, offset, &chunk, &start);
3459                 chunk++;
3460
3461                 /* OK now check for the curveball where the start and end are in
3462                  * the same chunk.
3463                  */
3464                 if ((start + n) < dev->nDataBytesPerChunk)
3465                         nToCopy = n;
3466                 else
3467                         nToCopy = dev->nDataBytesPerChunk - start;
3468
3469                 cache = yaffs_FindChunkCache(in, chunk);
3470
3471                 /* If the chunk is already in the cache or it is less than a whole chunk
3472                  * or we're using inband tags then use the cache (if there is caching)
3473                  * else bypass the cache.
3474                  */
3475                 if (cache || nToCopy != dev->nDataBytesPerChunk || dev->param.inbandTags) {
3476                         if (dev->param.nShortOpCaches > 0) {
3477
3478                                 /* If we can't find the data in the cache, then load it up. */
3479
3480                                 if (!cache) {
3481                                         cache = yaffs_GrabChunkCache(in->myDev);
3482                                         cache->object = in;
3483                                         cache->chunkId = chunk;
3484                                         cache->dirty = 0;
3485                                         cache->locked = 0;
3486                                         yaffs_ReadChunkDataFromObject(in, chunk,
3487                                                                       cache->
3488                                                                       data);
3489                                         cache->nBytes = 0;
3490                                 }
3491
3492                                 yaffs_UseChunkCache(dev, cache, 0);
3493
3494                                 cache->locked = 1;
3495
3496
3497                                 memcpy(buffer, &cache->data[start], nToCopy);
3498
3499                                 cache->locked = 0;
3500                         } else {
3501                                 /* Read into the local buffer then copy..*/
3502
3503                                 __u8 *localBuffer =
3504                                     yaffs_GetTempBuffer(dev, __LINE__);
3505                                 yaffs_ReadChunkDataFromObject(in, chunk,
3506                                                               localBuffer);
3507
3508                                 memcpy(buffer, &localBuffer[start], nToCopy);
3509
3510
3511                                 yaffs_ReleaseTempBuffer(dev, localBuffer,
3512                                                         __LINE__);
3513                         }
3514
3515                 } else {
3516
3517                         /* A full chunk. Read directly into the supplied buffer. */
3518                         yaffs_ReadChunkDataFromObject(in, chunk, buffer);
3519
3520                 }
3521
3522                 n -= nToCopy;
3523                 offset += nToCopy;
3524                 buffer += nToCopy;
3525                 nDone += nToCopy;
3526
3527         }
3528
3529         return nDone;
3530 }
3531
3532 int yaffs_DoWriteDataToFile(yaffs_Object *in, const __u8 *buffer, loff_t offset,
3533                         int nBytes, int writeThrough)
3534 {
3535
3536         int chunk;
3537         __u32 start;
3538         int nToCopy;
3539         int n = nBytes;
3540         int nDone = 0;
3541         int nToWriteBack;
3542         int startOfWrite = offset;
3543         int chunkWritten = 0;
3544         __u32 nBytesRead;
3545         __u32 chunkStart;
3546
3547         yaffs_Device *dev;
3548
3549         dev = in->myDev;
3550
3551         while (n > 0 && chunkWritten >= 0) {
3552                 yaffs_AddrToChunk(dev, offset, &chunk, &start);
3553
3554                 if (chunk * dev->nDataBytesPerChunk + start != offset ||
3555                                 start >= dev->nDataBytesPerChunk) {
3556                         T(YAFFS_TRACE_ERROR, (
3557                            TSTR("AddrToChunk of offset %d gives chunk %d start %d"
3558                            TENDSTR),
3559                            (int)offset, chunk, start));
3560                 }
3561                 chunk++; /* File pos to chunk in file offset */
3562
3563                 /* OK now check for the curveball where the start and end are in
3564                  * the same chunk.
3565                  */
3566
3567                 if ((start + n) < dev->nDataBytesPerChunk) {
3568                         nToCopy = n;
3569
3570                         /* Now folks, to calculate how many bytes to write back....
3571                          * If we're overwriting and not writing to then end of file then
3572                          * we need to write back as much as was there before.
3573                          */
3574
3575                         chunkStart = ((chunk - 1) * dev->nDataBytesPerChunk);
3576
3577                         if (chunkStart > in->variant.fileVariant.fileSize)
3578                                 nBytesRead = 0; /* Past end of file */
3579                         else
3580                                 nBytesRead = in->variant.fileVariant.fileSize - chunkStart;
3581
3582                         if (nBytesRead > dev->nDataBytesPerChunk)
3583                                 nBytesRead = dev->nDataBytesPerChunk;
3584
3585                         nToWriteBack =
3586                             (nBytesRead >
3587                              (start + n)) ? nBytesRead : (start + n);
3588
3589                         if (nToWriteBack < 0 || nToWriteBack > dev->nDataBytesPerChunk)
3590                                 YBUG();
3591
3592                 } else {
3593                         nToCopy = dev->nDataBytesPerChunk - start;
3594                         nToWriteBack = dev->nDataBytesPerChunk;
3595                 }
3596
3597                 if (nToCopy != dev->nDataBytesPerChunk || dev->param.inbandTags) {
3598                         /* An incomplete start or end chunk (or maybe both start and end chunk),
3599                          * or we're using inband tags, so we want to use the cache buffers.
3600                          */
3601                         if (dev->param.nShortOpCaches > 0) {
3602                                 yaffs_ChunkCache *cache;
3603                                 /* If we can't find the data in the cache, then load the cache */
3604                                 cache = yaffs_FindChunkCache(in, chunk);
3605
3606                                 if (!cache
3607                                     && yaffs_CheckSpaceForAllocation(dev, 1)) {
3608                                         cache = yaffs_GrabChunkCache(dev);
3609                                         cache->object = in;
3610                                         cache->chunkId = chunk;
3611                                         cache->dirty = 0;
3612                                         cache->locked = 0;
3613                                         yaffs_ReadChunkDataFromObject(in, chunk,
3614                                                                       cache->data);
3615                                 } else if (cache &&
3616                                         !cache->dirty &&
3617                                         !yaffs_CheckSpaceForAllocation(dev, 1)) {
3618                                         /* Drop the cache if it was a read cache item and
3619                                          * no space check has been made for it.
3620                                          */
3621                                          cache = NULL;
3622                                 }
3623
3624                                 if (cache) {
3625                                         yaffs_UseChunkCache(dev, cache, 1);
3626                                         cache->locked = 1;
3627
3628
3629                                         memcpy(&cache->data[start], buffer,
3630                                                nToCopy);
3631
3632
3633                                         cache->locked = 0;
3634                                         cache->nBytes = nToWriteBack;
3635
3636                                         if (writeThrough) {
3637                                                 chunkWritten =
3638                                                     yaffs_WriteChunkDataToObject
3639                                                     (cache->object,
3640                                                      cache->chunkId,
3641                                                      cache->data, cache->nBytes,
3642                                                      1);
3643                                                 cache->dirty = 0;
3644                                         }
3645
3646                                 } else {
3647                                         chunkWritten = -1;      /* fail the write */
3648                                 }
3649                         } else {
3650                                 /* An incomplete start or end chunk (or maybe both start and end chunk)
3651                                  * Read into the local buffer then copy, then copy over and write back.
3652                                  */
3653
3654                                 __u8 *localBuffer =
3655                                     yaffs_GetTempBuffer(dev, __LINE__);
3656
3657                                 yaffs_ReadChunkDataFromObject(in, chunk,
3658                                                               localBuffer);
3659
3660
3661
3662                                 memcpy(&localBuffer[start], buffer, nToCopy);
3663
3664                                 chunkWritten =
3665                                     yaffs_WriteChunkDataToObject(in, chunk,
3666                                                                  localBuffer,
3667                                                                  nToWriteBack,
3668                                                                  0);
3669
3670                                 yaffs_ReleaseTempBuffer(dev, localBuffer,
3671                                                         __LINE__);
3672
3673                         }
3674
3675                 } else {
3676                         /* A full chunk. Write directly from the supplied buffer. */
3677
3678
3679
3680                         chunkWritten =
3681                             yaffs_WriteChunkDataToObject(in, chunk, buffer,
3682                                                          dev->nDataBytesPerChunk,
3683                                                          0);
3684
3685                         /* Since we've overwritten the cached data, we better invalidate it. */
3686                         yaffs_InvalidateChunkCache(in, chunk);
3687                 }
3688
3689                 if (chunkWritten >= 0) {
3690                         n -= nToCopy;
3691                         offset += nToCopy;
3692                         buffer += nToCopy;
3693                         nDone += nToCopy;
3694                 }
3695
3696         }
3697
3698         /* Update file object */
3699
3700         if ((startOfWrite + nDone) > in->variant.fileVariant.fileSize)
3701                 in->variant.fileVariant.fileSize = (startOfWrite + nDone);
3702
3703         in->dirty = 1;
3704
3705         return nDone;
3706 }
3707
3708 int yaffs_WriteDataToFile(yaffs_Object *in, const __u8 *buffer, loff_t offset,
3709                         int nBytes, int writeThrough)
3710 {
3711         yaffs2_HandleHole(in,offset);
3712         return yaffs_DoWriteDataToFile(in,buffer,offset,nBytes,writeThrough);
3713 }
3714
3715
3716
3717 /* ---------------------- File resizing stuff ------------------ */
3718
3719 static void yaffs_PruneResizedChunks(yaffs_Object *in, int newSize)
3720 {
3721
3722         yaffs_Device *dev = in->myDev;
3723         int oldFileSize = in->variant.fileVariant.fileSize;
3724
3725         int lastDel = 1 + (oldFileSize - 1) / dev->nDataBytesPerChunk;
3726
3727         int startDel = 1 + (newSize + dev->nDataBytesPerChunk - 1) /
3728             dev->nDataBytesPerChunk;
3729         int i;
3730         int chunkId;
3731
3732         /* Delete backwards so that we don't end up with holes if
3733          * power is lost part-way through the operation.
3734          */
3735         for (i = lastDel; i >= startDel; i--) {
3736                 /* NB this could be optimised somewhat,
3737                  * eg. could retrieve the tags and write them without
3738                  * using yaffs_DeleteChunk
3739                  */
3740
3741                 chunkId = yaffs_FindAndDeleteChunkInFile(in, i, NULL);
3742                 if (chunkId > 0) {
3743                         if (chunkId <
3744                             (dev->internalStartBlock * dev->param.nChunksPerBlock)
3745                             || chunkId >=
3746                             ((dev->internalEndBlock +
3747                               1) * dev->param.nChunksPerBlock)) {
3748                                 T(YAFFS_TRACE_ALWAYS,
3749                                   (TSTR("Found daft chunkId %d for %d" TENDSTR),
3750                                    chunkId, i));
3751                         } else {
3752                                 in->nDataChunks--;
3753                                 yaffs_DeleteChunk(dev, chunkId, 1, __LINE__);
3754                         }
3755                 }
3756         }
3757
3758 }
3759
3760
3761 void yaffs_ResizeDown( yaffs_Object *obj, loff_t newSize)
3762 {
3763         int newFullChunks;
3764         __u32 newSizeOfPartialChunk;
3765         yaffs_Device *dev = obj->myDev;
3766
3767         yaffs_AddrToChunk(dev, newSize, &newFullChunks, &newSizeOfPartialChunk);
3768
3769         yaffs_PruneResizedChunks(obj, newSize);
3770
3771         if (newSizeOfPartialChunk != 0) {
3772                 int lastChunk = 1 + newFullChunks;
3773                 __u8 *localBuffer = yaffs_GetTempBuffer(dev, __LINE__);
3774
3775                 /* Got to read and rewrite the last chunk with its new size and zero pad */
3776                 yaffs_ReadChunkDataFromObject(obj, lastChunk, localBuffer);
3777                 memset(localBuffer + newSizeOfPartialChunk, 0,
3778                         dev->nDataBytesPerChunk - newSizeOfPartialChunk);
3779
3780                 yaffs_WriteChunkDataToObject(obj, lastChunk, localBuffer,
3781                                              newSizeOfPartialChunk, 1);
3782
3783                 yaffs_ReleaseTempBuffer(dev, localBuffer, __LINE__);
3784         }
3785
3786         obj->variant.fileVariant.fileSize = newSize;
3787
3788         yaffs_PruneFileStructure(dev, &obj->variant.fileVariant);
3789 }
3790
3791
3792 int yaffs_ResizeFile(yaffs_Object *in, loff_t newSize)
3793 {
3794         yaffs_Device *dev = in->myDev;
3795         int oldFileSize = in->variant.fileVariant.fileSize;
3796
3797         yaffs_FlushFilesChunkCache(in);
3798         yaffs_InvalidateWholeChunkCache(in);
3799
3800         yaffs_CheckGarbageCollection(dev,0);
3801
3802         if (in->variantType != YAFFS_OBJECT_TYPE_FILE)
3803                 return YAFFS_FAIL;
3804
3805         if (newSize == oldFileSize)
3806                 return YAFFS_OK;
3807
3808         if(newSize > oldFileSize){
3809                 yaffs2_HandleHole(in,newSize);
3810                 in->variant.fileVariant.fileSize = newSize;
3811         } else {
3812                 /* newSize < oldFileSize */
3813                 yaffs_ResizeDown(in, newSize);
3814         }
3815
3816         /* Write a new object header to reflect the resize.
3817          * show we've shrunk the file, if need be
3818          * Do this only if the file is not in the deleted directories
3819          * and is not shadowed.
3820          */
3821         if (in->parent &&
3822             !in->isShadowed &&
3823             in->parent->objectId != YAFFS_OBJECTID_UNLINKED &&
3824             in->parent->objectId != YAFFS_OBJECTID_DELETED)
3825                 yaffs_UpdateObjectHeader(in, NULL, 0, 0, 0, NULL);
3826
3827
3828         return YAFFS_OK;
3829 }
3830
3831 loff_t yaffs_GetFileSize(yaffs_Object *obj)
3832 {
3833         YCHAR *alias = NULL;
3834         obj = yaffs_GetEquivalentObject(obj);
3835
3836         switch (obj->variantType) {
3837         case YAFFS_OBJECT_TYPE_FILE:
3838                 return obj->variant.fileVariant.fileSize;
3839         case YAFFS_OBJECT_TYPE_SYMLINK:
3840                 alias = obj->variant.symLinkVariant.alias;
3841                 if(!alias)
3842                         return 0;
3843                 return yaffs_strnlen(alias,YAFFS_MAX_ALIAS_LENGTH);
3844         default:
3845                 return 0;
3846         }
3847 }
3848
3849
3850
3851 int yaffs_FlushFile(yaffs_Object *in, int updateTime, int dataSync)
3852 {
3853         int retVal;
3854         if (in->dirty) {
3855                 yaffs_FlushFilesChunkCache(in);
3856                 if(dataSync) /* Only sync data */
3857                         retVal=YAFFS_OK;
3858                 else {
3859                         if (updateTime) {
3860 #ifdef CONFIG_YAFFS_WINCE
3861                                 yfsd_WinFileTimeNow(in->win_mtime);
3862 #else
3863
3864                                 in->yst_mtime = Y_CURRENT_TIME;
3865
3866 #endif
3867                         }
3868
3869                         retVal = (yaffs_UpdateObjectHeader(in, NULL, 0, 0, 0, NULL) >=
3870                                 0) ? YAFFS_OK : YAFFS_FAIL;
3871                 }
3872         } else {
3873                 retVal = YAFFS_OK;
3874         }
3875
3876         return retVal;
3877
3878 }
3879
3880 static int yaffs_DoGenericObjectDeletion(yaffs_Object *in)
3881 {
3882
3883         /* First off, invalidate the file's data in the cache, without flushing. */
3884         yaffs_InvalidateWholeChunkCache(in);
3885
3886         if (in->myDev->param.isYaffs2 && (in->parent != in->myDev->deletedDir)) {
3887                 /* Move to the unlinked directory so we have a record that it was deleted. */
3888                 yaffs_ChangeObjectName(in, in->myDev->deletedDir, _Y("deleted"), 0, 0);
3889
3890         }
3891
3892         yaffs_RemoveObjectFromDirectory(in);
3893         yaffs_DeleteChunk(in->myDev, in->hdrChunk, 1, __LINE__);
3894         in->hdrChunk = 0;
3895
3896         yaffs_FreeObject(in);
3897         return YAFFS_OK;
3898
3899 }
3900
3901 /* yaffs_DeleteFile deletes the whole file data
3902  * and the inode associated with the file.
3903  * It does not delete the links associated with the file.
3904  */
3905 static int yaffs_UnlinkFileIfNeeded(yaffs_Object *in)
3906 {
3907
3908         int retVal;
3909         int immediateDeletion = 0;
3910         yaffs_Device *dev = in->myDev;
3911
3912         if (!in->myInode)
3913                 immediateDeletion = 1;
3914
3915         if (immediateDeletion) {
3916                 retVal =
3917                     yaffs_ChangeObjectName(in, in->myDev->deletedDir,
3918                                            _Y("deleted"), 0, 0);
3919                 T(YAFFS_TRACE_TRACING,
3920                   (TSTR("yaffs: immediate deletion of file %d" TENDSTR),
3921                    in->objectId));
3922                 in->deleted = 1;
3923                 in->myDev->nDeletedFiles++;
3924                 if (dev->param.disableSoftDelete || dev->param.isYaffs2)
3925                         yaffs_ResizeFile(in, 0);
3926                 yaffs_SoftDeleteFile(in);
3927         } else {
3928                 retVal =
3929                     yaffs_ChangeObjectName(in, in->myDev->unlinkedDir,
3930                                            _Y("unlinked"), 0, 0);
3931         }
3932
3933
3934         return retVal;
3935 }
3936
3937 int yaffs_DeleteFile(yaffs_Object *in)
3938 {
3939         int retVal = YAFFS_OK;
3940         int deleted; /* Need to cache value on stack if in is freed */
3941         yaffs_Device *dev = in->myDev;
3942
3943         if (dev->param.disableSoftDelete || dev->param.isYaffs2)
3944                 yaffs_ResizeFile(in, 0);
3945
3946         if (in->nDataChunks > 0) {
3947                 /* Use soft deletion if there is data in the file.
3948                  * That won't be the case if it has been resized to zero.
3949                  */
3950                 if (!in->unlinked)
3951                         retVal = yaffs_UnlinkFileIfNeeded(in);
3952
3953                 deleted = in->deleted;
3954
3955                 if (retVal == YAFFS_OK && in->unlinked && !in->deleted) {
3956                         in->deleted = 1;
3957                         deleted = 1;
3958                         in->myDev->nDeletedFiles++;
3959                         yaffs_SoftDeleteFile(in);
3960                 }
3961                 return deleted ? YAFFS_OK : YAFFS_FAIL;
3962         } else {
3963                 /* The file has no data chunks so we toss it immediately */
3964                 yaffs_FreeTnode(in->myDev, in->variant.fileVariant.top);
3965                 in->variant.fileVariant.top = NULL;
3966                 yaffs_DoGenericObjectDeletion(in);
3967
3968                 return YAFFS_OK;
3969         }
3970 }
3971
3972 static int yaffs_IsNonEmptyDirectory(yaffs_Object *obj)
3973 {
3974         return (obj->variantType == YAFFS_OBJECT_TYPE_DIRECTORY) &&
3975                 !(ylist_empty(&obj->variant.directoryVariant.children));
3976 }
3977
3978 static int yaffs_DeleteDirectory(yaffs_Object *obj)
3979 {
3980         /* First check that the directory is empty. */
3981         if (yaffs_IsNonEmptyDirectory(obj))
3982                 return YAFFS_FAIL;
3983
3984         return yaffs_DoGenericObjectDeletion(obj);
3985 }
3986
3987 static int yaffs_DeleteSymLink(yaffs_Object *in)
3988 {
3989         if(in->variant.symLinkVariant.alias)
3990                 YFREE(in->variant.symLinkVariant.alias);
3991         in->variant.symLinkVariant.alias=NULL;
3992
3993         return yaffs_DoGenericObjectDeletion(in);
3994 }
3995
3996 static int yaffs_DeleteHardLink(yaffs_Object *in)
3997 {
3998         /* remove this hardlink from the list assocaited with the equivalent
3999          * object
4000          */
4001         ylist_del_init(&in->hardLinks);
4002         return yaffs_DoGenericObjectDeletion(in);
4003 }
4004
4005 int yaffs_DeleteObject(yaffs_Object *obj)
4006 {
4007 int retVal = -1;
4008         switch (obj->variantType) {
4009         case YAFFS_OBJECT_TYPE_FILE:
4010                 retVal = yaffs_DeleteFile(obj);
4011                 break;
4012         case YAFFS_OBJECT_TYPE_DIRECTORY:
4013                 if(!ylist_empty(&obj->variant.directoryVariant.dirty)){
4014                         T(YAFFS_TRACE_BACKGROUND, (TSTR("Remove object %d from dirty directories" TENDSTR),obj->objectId));
4015                         ylist_del_init(&obj->variant.directoryVariant.dirty);
4016                 }
4017                 return yaffs_DeleteDirectory(obj);
4018                 break;
4019         case YAFFS_OBJECT_TYPE_SYMLINK:
4020                 retVal = yaffs_DeleteSymLink(obj);
4021                 break;
4022         case YAFFS_OBJECT_TYPE_HARDLINK:
4023                 retVal = yaffs_DeleteHardLink(obj);
4024                 break;
4025         case YAFFS_OBJECT_TYPE_SPECIAL:
4026                 retVal = yaffs_DoGenericObjectDeletion(obj);
4027                 break;
4028         case YAFFS_OBJECT_TYPE_UNKNOWN:
4029                 retVal = 0;
4030                 break;          /* should not happen. */
4031         }
4032
4033         return retVal;
4034 }
4035
4036 static int yaffs_UnlinkWorker(yaffs_Object *obj)
4037 {
4038
4039         int immediateDeletion = 0;
4040
4041         if (!obj->myInode)
4042                 immediateDeletion = 1;
4043
4044         if(obj)
4045                 yaffs_UpdateParent(obj->parent);
4046
4047         if (obj->variantType == YAFFS_OBJECT_TYPE_HARDLINK) {
4048                 return yaffs_DeleteHardLink(obj);
4049         } else if (!ylist_empty(&obj->hardLinks)) {
4050                 /* Curve ball: We're unlinking an object that has a hardlink.
4051                  *
4052                  * This problem arises because we are not strictly following
4053                  * The Linux link/inode model.
4054                  *
4055                  * We can't really delete the object.
4056                  * Instead, we do the following:
4057                  * - Select a hardlink.
4058                  * - Unhook it from the hard links
4059                  * - Move it from its parent directory (so that the rename can work)
4060                  * - Rename the object to the hardlink's name.
4061                  * - Delete the hardlink
4062                  */
4063
4064                 yaffs_Object *hl;
4065                 yaffs_Object *parent;
4066                 int retVal;
4067                 YCHAR name[YAFFS_MAX_NAME_LENGTH + 1];
4068
4069                 hl = ylist_entry(obj->hardLinks.next, yaffs_Object, hardLinks);
4070
4071                 yaffs_GetObjectName(hl, name, YAFFS_MAX_NAME_LENGTH + 1);
4072                 parent = hl->parent;
4073
4074                 ylist_del_init(&hl->hardLinks);
4075
4076                 yaffs_AddObjectToDirectory(obj->myDev->unlinkedDir, hl);
4077
4078                 retVal = yaffs_ChangeObjectName(obj,parent, name, 0, 0);
4079
4080                 if (retVal == YAFFS_OK)
4081                         retVal = yaffs_DoGenericObjectDeletion(hl);
4082
4083                 return retVal;
4084
4085         } else if (immediateDeletion) {
4086                 switch (obj->variantType) {
4087                 case YAFFS_OBJECT_TYPE_FILE:
4088                         return yaffs_DeleteFile(obj);
4089                         break;
4090                 case YAFFS_OBJECT_TYPE_DIRECTORY:
4091                         ylist_del_init(&obj->variant.directoryVariant.dirty);
4092                         return yaffs_DeleteDirectory(obj);
4093                         break;
4094                 case YAFFS_OBJECT_TYPE_SYMLINK:
4095                         return yaffs_DeleteSymLink(obj);
4096                         break;
4097                 case YAFFS_OBJECT_TYPE_SPECIAL:
4098                         return yaffs_DoGenericObjectDeletion(obj);
4099                         break;
4100                 case YAFFS_OBJECT_TYPE_HARDLINK:
4101                 case YAFFS_OBJECT_TYPE_UNKNOWN:
4102                 default:
4103                         return YAFFS_FAIL;
4104                 }
4105         } else if(yaffs_IsNonEmptyDirectory(obj))
4106                 return YAFFS_FAIL;
4107         else
4108                 return yaffs_ChangeObjectName(obj, obj->myDev->unlinkedDir,
4109                                            _Y("unlinked"), 0, 0);
4110 }
4111
4112
4113 static int yaffs_UnlinkObject(yaffs_Object *obj)
4114 {
4115
4116         if (obj && obj->unlinkAllowed)
4117                 return yaffs_UnlinkWorker(obj);
4118
4119         return YAFFS_FAIL;
4120
4121 }
4122 int yaffs_Unlink(yaffs_Object *dir, const YCHAR *name)
4123 {
4124         yaffs_Object *obj;
4125
4126         obj = yaffs_FindObjectByName(dir, name);
4127         return yaffs_UnlinkObject(obj);
4128 }
4129
4130 /*----------------------- Initialisation Scanning ---------------------- */
4131
4132 void yaffs_HandleShadowedObject(yaffs_Device *dev, int objId,
4133                                 int backwardScanning)
4134 {
4135         yaffs_Object *obj;
4136
4137         if (!backwardScanning) {
4138                 /* Handle YAFFS1 forward scanning case
4139                  * For YAFFS1 we always do the deletion
4140                  */
4141
4142         } else {
4143                 /* Handle YAFFS2 case (backward scanning)
4144                  * If the shadowed object exists then ignore.
4145                  */
4146                 obj = yaffs_FindObjectByNumber(dev, objId);
4147                 if(obj)
4148                         return;
4149         }
4150
4151         /* Let's create it (if it does not exist) assuming it is a file so that it can do shrinking etc.
4152          * We put it in unlinked dir to be cleaned up after the scanning
4153          */
4154         obj =
4155             yaffs_FindOrCreateObjectByNumber(dev, objId,
4156                                              YAFFS_OBJECT_TYPE_FILE);
4157         if (!obj)
4158                 return;
4159         obj->isShadowed = 1;
4160         yaffs_AddObjectToDirectory(dev->unlinkedDir, obj);
4161         obj->variant.fileVariant.shrinkSize = 0;
4162         obj->valid = 1;         /* So that we don't read any other info for this file */
4163
4164 }
4165
4166
4167 void yaffs_HardlinkFixup(yaffs_Device *dev, yaffs_Object *hardList)
4168 {
4169         yaffs_Object *hl;
4170         yaffs_Object *in;
4171
4172         while (hardList) {
4173                 hl = hardList;
4174                 hardList = (yaffs_Object *) (hardList->hardLinks.next);
4175
4176                 in = yaffs_FindObjectByNumber(dev,
4177                                               hl->variant.hardLinkVariant.
4178                                               equivalentObjectId);
4179
4180                 if (in) {
4181                         /* Add the hardlink pointers */
4182                         hl->variant.hardLinkVariant.equivalentObject = in;
4183                         ylist_add(&hl->hardLinks, &in->hardLinks);
4184                 } else {
4185                         /* Todo Need to report/handle this better.
4186                          * Got a problem... hardlink to a non-existant object
4187                          */
4188                         hl->variant.hardLinkVariant.equivalentObject = NULL;
4189                         YINIT_LIST_HEAD(&hl->hardLinks);
4190
4191                 }
4192         }
4193 }
4194
4195
4196 static void yaffs_StripDeletedObjects(yaffs_Device *dev)
4197 {
4198         /*
4199         *  Sort out state of unlinked and deleted objects after scanning.
4200         */
4201         struct ylist_head *i;
4202         struct ylist_head *n;
4203         yaffs_Object *l;
4204
4205         if (dev->readOnly)
4206                 return;
4207
4208         /* Soft delete all the unlinked files */
4209         ylist_for_each_safe(i, n,
4210                 &dev->unlinkedDir->variant.directoryVariant.children) {
4211                 if (i) {
4212                         l = ylist_entry(i, yaffs_Object, siblings);
4213                         yaffs_DeleteObject(l);
4214                 }
4215         }
4216
4217         ylist_for_each_safe(i, n,
4218                 &dev->deletedDir->variant.directoryVariant.children) {
4219                 if (i) {
4220                         l = ylist_entry(i, yaffs_Object, siblings);
4221                         yaffs_DeleteObject(l);
4222                 }
4223         }
4224
4225 }
4226
4227 /*
4228  * This code iterates through all the objects making sure that they are rooted.
4229  * Any unrooted objects are re-rooted in lost+found.
4230  * An object needs to be in one of:
4231  * - Directly under deleted, unlinked
4232  * - Directly or indirectly under root.
4233  *
4234  * Note:
4235  *  This code assumes that we don't ever change the current relationships between
4236  *  directories:
4237  *   rootDir->parent == unlinkedDir->parent == deletedDir->parent == NULL
4238  *   lostNfound->parent == rootDir
4239  *
4240  * This fixes the problem where directories might have inadvertently been deleted
4241  * leaving the object "hanging" without being rooted in the directory tree.
4242  */
4243
4244 static int yaffs_HasNULLParent(yaffs_Device *dev, yaffs_Object *obj)
4245 {
4246         return (obj == dev->deletedDir ||
4247                 obj == dev->unlinkedDir||
4248                 obj == dev->rootDir);
4249 }
4250
4251 static void yaffs_FixHangingObjects(yaffs_Device *dev)
4252 {
4253         yaffs_Object *obj;
4254         yaffs_Object *parent;
4255         int i;
4256         struct ylist_head *lh;
4257         struct ylist_head *n;
4258         int depthLimit;
4259         int hanging;
4260
4261         if (dev->readOnly)
4262                 return;
4263
4264         /* Iterate through the objects in each hash entry,
4265          * looking at each object.
4266          * Make sure it is rooted.
4267          */
4268
4269         for (i = 0; i <  YAFFS_NOBJECT_BUCKETS; i++) {
4270                 ylist_for_each_safe(lh, n, &dev->objectBucket[i].list) {
4271                         if (lh) {
4272                                 obj = ylist_entry(lh, yaffs_Object, hashLink);
4273                                 parent= obj->parent;
4274
4275                                 if(yaffs_HasNULLParent(dev,obj)){
4276                                         /* These directories are not hanging */
4277                                         hanging = 0;
4278                                 }
4279                                 else if(!parent || parent->variantType != YAFFS_OBJECT_TYPE_DIRECTORY)
4280                                         hanging = 1;
4281                                 else if(yaffs_HasNULLParent(dev,parent))
4282                                         hanging = 0;
4283                                 else {
4284                                         /*
4285                                          * Need to follow the parent chain to see if it is hanging.
4286                                          */
4287                                         hanging = 0;
4288                                         depthLimit=100;
4289
4290                                         while(parent != dev->rootDir &&
4291                                                 parent->parent &&
4292                                                 parent->parent->variantType == YAFFS_OBJECT_TYPE_DIRECTORY &&
4293                                                 depthLimit > 0){
4294                                                 parent = parent->parent;
4295                                                 depthLimit--;
4296                                         }
4297                                         if(parent != dev->rootDir)
4298                                                 hanging = 1;
4299                                 }
4300                                 if(hanging){
4301                                         T(YAFFS_TRACE_SCAN,
4302                                           (TSTR("Hanging object %d moved to lost and found" TENDSTR),
4303                                                 obj->objectId));
4304                                         yaffs_AddObjectToDirectory(dev->lostNFoundDir,obj);
4305                                 }
4306                         }
4307                 }
4308         }
4309 }
4310
4311
4312 /*
4313  * Delete directory contents for cleaning up lost and found.
4314  */
4315 static void yaffs_DeleteDirectoryContents(yaffs_Object *dir)
4316 {
4317         yaffs_Object *obj;
4318         struct ylist_head *lh;
4319         struct ylist_head *n;
4320
4321         if(dir->variantType != YAFFS_OBJECT_TYPE_DIRECTORY)
4322                 YBUG();
4323
4324         ylist_for_each_safe(lh, n, &dir->variant.directoryVariant.children) {
4325                 if (lh) {
4326                         obj = ylist_entry(lh, yaffs_Object, siblings);
4327                         if(obj->variantType == YAFFS_OBJECT_TYPE_DIRECTORY)
4328                                 yaffs_DeleteDirectoryContents(obj);
4329
4330                         T(YAFFS_TRACE_SCAN,
4331                                 (TSTR("Deleting lost_found object %d" TENDSTR),
4332                                 obj->objectId));
4333
4334                         /* Need to use UnlinkObject since Delete would not handle
4335                          * hardlinked objects correctly.
4336                          */
4337                         yaffs_UnlinkObject(obj);
4338                 }
4339         }
4340
4341 }
4342
4343 static void yaffs_EmptyLostAndFound(yaffs_Device *dev)
4344 {
4345         yaffs_DeleteDirectoryContents(dev->lostNFoundDir);
4346 }
4347
4348 static void yaffs_CheckObjectDetailsLoaded(yaffs_Object *in)
4349 {
4350         __u8 *chunkData;
4351         yaffs_ObjectHeader *oh;
4352         yaffs_Device *dev;
4353         yaffs_ExtendedTags tags;
4354         int result;
4355         int alloc_failed = 0;
4356
4357         if (!in)
4358                 return;
4359
4360         dev = in->myDev;
4361
4362 #if 0
4363         T(YAFFS_TRACE_SCAN, (TSTR("details for object %d %s loaded" TENDSTR),
4364                 in->objectId,
4365                 in->lazyLoaded ? "not yet" : "already"));
4366 #endif
4367
4368         if (in->lazyLoaded && in->hdrChunk > 0) {
4369                 in->lazyLoaded = 0;
4370                 chunkData = yaffs_GetTempBuffer(dev, __LINE__);
4371
4372                 result = yaffs_ReadChunkWithTagsFromNAND(dev, in->hdrChunk, chunkData, &tags);
4373                 oh = (yaffs_ObjectHeader *) chunkData;
4374
4375                 in->yst_mode = oh->yst_mode;
4376 #ifdef CONFIG_YAFFS_WINCE
4377                 in->win_atime[0] = oh->win_atime[0];
4378                 in->win_ctime[0] = oh->win_ctime[0];
4379                 in->win_mtime[0] = oh->win_mtime[0];
4380                 in->win_atime[1] = oh->win_atime[1];
4381                 in->win_ctime[1] = oh->win_ctime[1];
4382                 in->win_mtime[1] = oh->win_mtime[1];
4383 #else
4384                 in->yst_uid = oh->yst_uid;
4385                 in->yst_gid = oh->yst_gid;
4386                 in->yst_atime = oh->yst_atime;
4387                 in->yst_mtime = oh->yst_mtime;
4388                 in->yst_ctime = oh->yst_ctime;
4389                 in->yst_rdev = oh->yst_rdev;
4390
4391 #endif
4392                 yaffs_SetObjectNameFromOH(in, oh);
4393
4394                 if (in->variantType == YAFFS_OBJECT_TYPE_SYMLINK) {
4395                         in->variant.symLinkVariant.alias =
4396                                                     yaffs_CloneString(oh->alias);
4397                         if (!in->variant.symLinkVariant.alias)
4398                                 alloc_failed = 1; /* Not returned to caller */
4399                 }
4400
4401                 yaffs_ReleaseTempBuffer(dev, chunkData, __LINE__);
4402         }
4403 }
4404
4405 /*------------------------------  Directory Functions ----------------------------- */
4406
4407 /*
4408  *yaffs_UpdateParent() handles fixing a directories mtime and ctime when a new
4409  * link (ie. name) is created or deleted in the directory.
4410  *
4411  * ie.
4412  *   create dir/a : update dir's mtime/ctime
4413  *   rm dir/a:   update dir's mtime/ctime
4414  *   modify dir/a: don't update dir's mtimme/ctime
4415  *
4416  * This can be handled immediately or defered. Defering helps reduce the number
4417  * of updates when many files in a directory are changed within a brief period.
4418  *
4419  * If the directory updating is defered then yaffs_UpdateDirtyDirecories must be
4420  * called periodically.
4421  */
4422
4423 static void yaffs_UpdateParent(yaffs_Object *obj)
4424 {
4425         yaffs_Device *dev;
4426         if(!obj)
4427                 return;
4428 #ifndef CONFIG_YAFFS_WINCE
4429
4430         dev = obj->myDev;
4431         obj->dirty = 1;
4432         obj->yst_mtime = obj->yst_ctime = Y_CURRENT_TIME;
4433         if(dev->param.deferDirectoryUpdate){
4434                 struct ylist_head *link = &obj->variant.directoryVariant.dirty;
4435
4436                 if(ylist_empty(link)){
4437                         ylist_add(link,&dev->dirtyDirectories);
4438                         T(YAFFS_TRACE_BACKGROUND, (TSTR("Added object %d to dirty directories" TENDSTR),obj->objectId));
4439                 }
4440
4441         } else
4442                 yaffs_UpdateObjectHeader(obj, NULL, 0, 0, 0, NULL);
4443 #endif
4444 }
4445
4446 void yaffs_UpdateDirtyDirectories(yaffs_Device *dev)
4447 {
4448         struct ylist_head *link;
4449         yaffs_Object *obj;
4450         yaffs_DirectoryStructure *dS;
4451         yaffs_ObjectVariant *oV;
4452
4453         T(YAFFS_TRACE_BACKGROUND, (TSTR("Update dirty directories" TENDSTR)));
4454
4455         while(!ylist_empty(&dev->dirtyDirectories)){
4456                 link = dev->dirtyDirectories.next;
4457                 ylist_del_init(link);
4458
4459                 dS=ylist_entry(link,yaffs_DirectoryStructure,dirty);
4460                 oV = ylist_entry(dS,yaffs_ObjectVariant,directoryVariant);
4461                 obj = ylist_entry(oV,yaffs_Object,variant);
4462
4463                 T(YAFFS_TRACE_BACKGROUND, (TSTR("Update directory %d" TENDSTR), obj->objectId));
4464
4465                 if(obj->dirty)
4466                         yaffs_UpdateObjectHeader(obj, NULL, 0, 0, 0, NULL);
4467         }
4468 }
4469
4470 static void yaffs_RemoveObjectFromDirectory(yaffs_Object *obj)
4471 {
4472         yaffs_Device *dev = obj->myDev;
4473         yaffs_Object *parent;
4474
4475         yaffs_VerifyObjectInDirectory(obj);
4476         parent = obj->parent;
4477
4478         yaffs_VerifyDirectory(parent);
4479
4480         if (dev && dev->param.removeObjectCallback)
4481                 dev->param.removeObjectCallback(obj);
4482
4483
4484         ylist_del_init(&obj->siblings);
4485         obj->parent = NULL;
4486
4487         yaffs_VerifyDirectory(parent);
4488 }
4489
4490 void yaffs_AddObjectToDirectory(yaffs_Object *directory,
4491                                         yaffs_Object *obj)
4492 {
4493         if (!directory) {
4494                 T(YAFFS_TRACE_ALWAYS,
4495                   (TSTR
4496                    ("tragedy: Trying to add an object to a null pointer directory"
4497                     TENDSTR)));
4498                 YBUG();
4499                 return;
4500         }
4501         if (directory->variantType != YAFFS_OBJECT_TYPE_DIRECTORY) {
4502                 T(YAFFS_TRACE_ALWAYS,
4503                   (TSTR
4504                    ("tragedy: Trying to add an object to a non-directory"
4505                     TENDSTR)));
4506                 YBUG();
4507         }
4508
4509         if (obj->siblings.prev == NULL) {
4510                 /* Not initialised */
4511                 YBUG();
4512         }
4513
4514
4515         yaffs_VerifyDirectory(directory);
4516
4517         yaffs_RemoveObjectFromDirectory(obj);
4518
4519
4520         /* Now add it */
4521         ylist_add(&obj->siblings, &directory->variant.directoryVariant.children);
4522         obj->parent = directory;
4523
4524         if (directory == obj->myDev->unlinkedDir
4525                         || directory == obj->myDev->deletedDir) {
4526                 obj->unlinked = 1;
4527                 obj->myDev->nUnlinkedFiles++;
4528                 obj->renameAllowed = 0;
4529         }
4530
4531         yaffs_VerifyDirectory(directory);
4532         yaffs_VerifyObjectInDirectory(obj);
4533 }
4534
4535 yaffs_Object *yaffs_FindObjectByName(yaffs_Object *directory,
4536                                      const YCHAR *name)
4537 {
4538         int sum;
4539
4540         struct ylist_head *i;
4541         YCHAR buffer[YAFFS_MAX_NAME_LENGTH + 1];
4542
4543         yaffs_Object *l;
4544
4545         if (!name)
4546                 return NULL;
4547
4548         if (!directory) {
4549                 T(YAFFS_TRACE_ALWAYS,
4550                   (TSTR
4551                    ("tragedy: yaffs_FindObjectByName: null pointer directory"
4552                     TENDSTR)));
4553                 YBUG();
4554                 return NULL;
4555         }
4556         if (directory->variantType != YAFFS_OBJECT_TYPE_DIRECTORY) {
4557                 T(YAFFS_TRACE_ALWAYS,
4558                   (TSTR
4559                    ("tragedy: yaffs_FindObjectByName: non-directory" TENDSTR)));
4560                 YBUG();
4561         }
4562
4563         sum = yaffs_CalcNameSum(name);
4564
4565         ylist_for_each(i, &directory->variant.directoryVariant.children) {
4566                 if (i) {
4567                         l = ylist_entry(i, yaffs_Object, siblings);
4568
4569                         if (l->parent != directory)
4570                                 YBUG();
4571
4572                         yaffs_CheckObjectDetailsLoaded(l);
4573
4574                         /* Special case for lost-n-found */
4575                         if (l->objectId == YAFFS_OBJECTID_LOSTNFOUND) {
4576                                 if (yaffs_strcmp(name, YAFFS_LOSTNFOUND_NAME) == 0)
4577                                         return l;
4578                         } else if (yaffs_SumCompare(l->sum, sum) || l->hdrChunk <= 0) {
4579                                 /* LostnFound chunk called Objxxx
4580                                  * Do a real check
4581                                  */
4582                                 yaffs_GetObjectName(l, buffer,
4583                                                     YAFFS_MAX_NAME_LENGTH + 1);
4584                                 if (yaffs_strncmp(name, buffer, YAFFS_MAX_NAME_LENGTH) == 0)
4585                                         return l;
4586                         }
4587                 }
4588         }
4589
4590         return NULL;
4591 }
4592
4593
4594 #if 0
4595 int yaffs_ApplyToDirectoryChildren(yaffs_Object *theDir,
4596                                         int (*fn) (yaffs_Object *))
4597 {
4598         struct ylist_head *i;
4599         yaffs_Object *l;
4600
4601         if (!theDir) {
4602                 T(YAFFS_TRACE_ALWAYS,
4603                   (TSTR
4604                    ("tragedy: yaffs_FindObjectByName: null pointer directory"
4605                     TENDSTR)));
4606                 YBUG();
4607                 return YAFFS_FAIL;
4608         }
4609         if (theDir->variantType != YAFFS_OBJECT_TYPE_DIRECTORY) {
4610                 T(YAFFS_TRACE_ALWAYS,
4611                   (TSTR
4612                    ("tragedy: yaffs_FindObjectByName: non-directory" TENDSTR)));
4613                 YBUG();
4614                 return YAFFS_FAIL;
4615         }
4616
4617         ylist_for_each(i, &theDir->variant.directoryVariant.children) {
4618                 if (i) {
4619                         l = ylist_entry(i, yaffs_Object, siblings);
4620                         if (l && !fn(l))
4621                                 return YAFFS_FAIL;
4622                 }
4623         }
4624
4625         return YAFFS_OK;
4626
4627 }
4628 #endif
4629
4630 /* GetEquivalentObject dereferences any hard links to get to the
4631  * actual object.
4632  */
4633
4634 yaffs_Object *yaffs_GetEquivalentObject(yaffs_Object *obj)
4635 {
4636         if (obj && obj->variantType == YAFFS_OBJECT_TYPE_HARDLINK) {
4637                 /* We want the object id of the equivalent object, not this one */
4638                 obj = obj->variant.hardLinkVariant.equivalentObject;
4639                 yaffs_CheckObjectDetailsLoaded(obj);
4640         }
4641         return obj;
4642 }
4643
4644 /*
4645  *  A note or two on object names.
4646  *  * If the object name is missing, we then make one up in the form objnnn
4647  *
4648  *  * ASCII names are stored in the object header's name field from byte zero
4649  *  * Unicode names are historically stored starting from byte zero.
4650  *
4651  * Then there are automatic Unicode names...
4652  * The purpose of these is to save names in a way that can be read as
4653  * ASCII or Unicode names as appropriate, thus allowing a Unicode and ASCII
4654  * system to share files.
4655  *
4656  * These automatic unicode are stored slightly differently...
4657  *  - If the name can fit in the ASCII character space then they are saved as
4658  *    ascii names as per above.
4659  *  - If the name needs Unicode then the name is saved in Unicode
4660  *    starting at oh->name[1].
4661
4662  */
4663 static void yaffs_FixNullName(yaffs_Object * obj,YCHAR * name, int buffSize)
4664 {
4665         /* Create an object name if we could not find one. */
4666         if(yaffs_strnlen(name,YAFFS_MAX_NAME_LENGTH) == 0){
4667                 YCHAR locName[20];
4668                 YCHAR numString[20];
4669                 YCHAR *x = &numString[19];
4670                 unsigned v = obj->objectId;
4671                 numString[19] = 0;
4672                 while(v>0){
4673                         x--;
4674                         *x = '0' + (v % 10);
4675                         v /= 10;
4676                 }
4677                 /* make up a name */
4678                 yaffs_strcpy(locName, YAFFS_LOSTNFOUND_PREFIX);
4679                 yaffs_strcat(locName,x);
4680                 yaffs_strncpy(name, locName, buffSize - 1);
4681         }
4682 }
4683
4684 static void yaffs_LoadNameFromObjectHeader(yaffs_Device *dev,YCHAR *name, const YCHAR *ohName, int bufferSize)
4685 {
4686 #ifdef CONFIG_YAFFS_AUTO_UNICODE
4687         if(dev->param.autoUnicode){
4688                 if(*ohName){
4689                         /* It is an ASCII name, so do an ASCII to unicode conversion */
4690                         const char *asciiOhName = (const char *)ohName;
4691                         int n = bufferSize - 1;
4692                         while(n > 0 && *asciiOhName){
4693                                 *name = *asciiOhName;
4694                                 name++;
4695                                 asciiOhName++;
4696                                 n--;
4697                         }
4698                 } else
4699                         yaffs_strncpy(name,ohName+1, bufferSize -1);
4700         } else
4701 #endif
4702                 yaffs_strncpy(name, ohName, bufferSize - 1);
4703 }
4704
4705
4706 static void yaffs_LoadObjectHeaderFromName(yaffs_Device *dev, YCHAR *ohName, const YCHAR *name)
4707 {
4708 #ifdef CONFIG_YAFFS_AUTO_UNICODE
4709
4710         int isAscii;
4711         YCHAR *w;
4712
4713         if(dev->param.autoUnicode){
4714
4715                 isAscii = 1;
4716                 w = name;
4717
4718                 /* Figure out if the name will fit in ascii character set */
4719                 while(isAscii && *w){
4720                         if((*w) & 0xff00)
4721                                 isAscii = 0;
4722                         w++;
4723                 }
4724
4725                 if(isAscii){
4726                         /* It is an ASCII name, so do a unicode to ascii conversion */
4727                         char *asciiOhName = (char *)ohName;
4728                         int n = YAFFS_MAX_NAME_LENGTH  - 1;
4729                         while(n > 0 && *name){
4730                                 *asciiOhName= *name;
4731                                 name++;
4732                                 asciiOhName++;
4733                                 n--;
4734                         }
4735                 } else{
4736                         /* It is a unicode name, so save starting at the second YCHAR */
4737                         *ohName = 0;
4738                         yaffs_strncpy(ohName+1,name, YAFFS_MAX_NAME_LENGTH -2);
4739                 }
4740         }
4741         else
4742 #endif
4743                 yaffs_strncpy(ohName,name, YAFFS_MAX_NAME_LENGTH - 1);
4744
4745 }
4746
4747 int yaffs_GetObjectName(yaffs_Object * obj, YCHAR * name, int buffSize)
4748 {
4749         memset(name, 0, buffSize * sizeof(YCHAR));
4750
4751         yaffs_CheckObjectDetailsLoaded(obj);
4752
4753         if (obj->objectId == YAFFS_OBJECTID_LOSTNFOUND) {
4754                 yaffs_strncpy(name, YAFFS_LOSTNFOUND_NAME, buffSize - 1);
4755         }
4756 #ifdef CONFIG_YAFFS_SHORT_NAMES_IN_RAM
4757         else if (obj->shortName[0]) {
4758                 yaffs_strcpy(name, obj->shortName);
4759         }
4760 #endif
4761         else if(obj->hdrChunk > 0) {
4762                 int result;
4763                 __u8 *buffer = yaffs_GetTempBuffer(obj->myDev, __LINE__);
4764
4765                 yaffs_ObjectHeader *oh = (yaffs_ObjectHeader *) buffer;
4766
4767                 memset(buffer, 0, obj->myDev->nDataBytesPerChunk);
4768
4769                 if (obj->hdrChunk > 0) {
4770                         result = yaffs_ReadChunkWithTagsFromNAND(obj->myDev,
4771                                                         obj->hdrChunk, buffer,
4772                                                         NULL);
4773                 }
4774                 yaffs_LoadNameFromObjectHeader(obj->myDev,name,oh->name,buffSize);
4775
4776                 yaffs_ReleaseTempBuffer(obj->myDev, buffer, __LINE__);
4777         }
4778
4779         yaffs_FixNullName(obj,name,buffSize);
4780
4781         return yaffs_strnlen(name,YAFFS_MAX_NAME_LENGTH);
4782 }
4783
4784
4785 int yaffs_GetObjectFileLength(yaffs_Object *obj)
4786 {
4787         /* Dereference any hard linking */
4788         obj = yaffs_GetEquivalentObject(obj);
4789
4790         if (obj->variantType == YAFFS_OBJECT_TYPE_FILE)
4791                 return obj->variant.fileVariant.fileSize;
4792         if (obj->variantType == YAFFS_OBJECT_TYPE_SYMLINK){
4793                 if(!obj->variant.symLinkVariant.alias)
4794                         return 0;
4795                 return yaffs_strnlen(obj->variant.symLinkVariant.alias,YAFFS_MAX_ALIAS_LENGTH);
4796         } else {
4797                 /* Only a directory should drop through to here */
4798                 return obj->myDev->nDataBytesPerChunk;
4799         }
4800 }
4801
4802 int yaffs_GetObjectLinkCount(yaffs_Object *obj)
4803 {
4804         int count = 0;
4805         struct ylist_head *i;
4806
4807         if (!obj->unlinked)
4808                 count++;                /* the object itself */
4809
4810         ylist_for_each(i, &obj->hardLinks)
4811                 count++;                /* add the hard links; */
4812
4813         return count;
4814 }
4815
4816 int yaffs_GetObjectInode(yaffs_Object *obj)
4817 {
4818         obj = yaffs_GetEquivalentObject(obj);
4819
4820         return obj->objectId;
4821 }
4822
4823 unsigned yaffs_GetObjectType(yaffs_Object *obj)
4824 {
4825         obj = yaffs_GetEquivalentObject(obj);
4826
4827         switch (obj->variantType) {
4828         case YAFFS_OBJECT_TYPE_FILE:
4829                 return DT_REG;
4830                 break;
4831         case YAFFS_OBJECT_TYPE_DIRECTORY:
4832                 return DT_DIR;
4833                 break;
4834         case YAFFS_OBJECT_TYPE_SYMLINK:
4835                 return DT_LNK;
4836                 break;
4837         case YAFFS_OBJECT_TYPE_HARDLINK:
4838                 return DT_REG;
4839                 break;
4840         case YAFFS_OBJECT_TYPE_SPECIAL:
4841                 if (S_ISFIFO(obj->yst_mode))
4842                         return DT_FIFO;
4843                 if (S_ISCHR(obj->yst_mode))
4844                         return DT_CHR;
4845                 if (S_ISBLK(obj->yst_mode))
4846                         return DT_BLK;
4847                 if (S_ISSOCK(obj->yst_mode))
4848                         return DT_SOCK;
4849         default:
4850                 return DT_REG;
4851                 break;
4852         }
4853 }
4854
4855 YCHAR *yaffs_GetSymlinkAlias(yaffs_Object *obj)
4856 {
4857         obj = yaffs_GetEquivalentObject(obj);
4858         if (obj->variantType == YAFFS_OBJECT_TYPE_SYMLINK)
4859                 return yaffs_CloneString(obj->variant.symLinkVariant.alias);
4860         else
4861                 return yaffs_CloneString(_Y(""));
4862 }
4863
4864 #ifndef CONFIG_YAFFS_WINCE
4865
4866 int yaffs_SetAttributes(yaffs_Object *obj, struct iattr *attr)
4867 {
4868         unsigned int valid = attr->ia_valid;
4869
4870         if (valid & ATTR_MODE)
4871                 obj->yst_mode = attr->ia_mode;
4872         if (valid & ATTR_UID)
4873                 obj->yst_uid = attr->ia_uid;
4874         if (valid & ATTR_GID)
4875                 obj->yst_gid = attr->ia_gid;
4876
4877         if (valid & ATTR_ATIME)
4878                 obj->yst_atime = Y_TIME_CONVERT(attr->ia_atime);
4879         if (valid & ATTR_CTIME)
4880                 obj->yst_ctime = Y_TIME_CONVERT(attr->ia_ctime);
4881         if (valid & ATTR_MTIME)
4882                 obj->yst_mtime = Y_TIME_CONVERT(attr->ia_mtime);
4883
4884         if (valid & ATTR_SIZE)
4885                 yaffs_ResizeFile(obj, attr->ia_size);
4886
4887         yaffs_UpdateObjectHeader(obj, NULL, 1, 0, 0, NULL);
4888
4889         return YAFFS_OK;
4890
4891 }
4892 int yaffs_GetAttributes(yaffs_Object *obj, struct iattr *attr)
4893 {
4894         unsigned int valid = 0;
4895
4896         attr->ia_mode = obj->yst_mode;
4897         valid |= ATTR_MODE;
4898         attr->ia_uid = obj->yst_uid;
4899         valid |= ATTR_UID;
4900         attr->ia_gid = obj->yst_gid;
4901         valid |= ATTR_GID;
4902
4903         Y_TIME_CONVERT(attr->ia_atime) = obj->yst_atime;
4904         valid |= ATTR_ATIME;
4905         Y_TIME_CONVERT(attr->ia_ctime) = obj->yst_ctime;
4906         valid |= ATTR_CTIME;
4907         Y_TIME_CONVERT(attr->ia_mtime) = obj->yst_mtime;
4908         valid |= ATTR_MTIME;
4909
4910         attr->ia_size = yaffs_GetFileSize(obj);
4911         valid |= ATTR_SIZE;
4912
4913         attr->ia_valid = valid;
4914
4915         return YAFFS_OK;
4916 }
4917
4918 #endif
4919
4920
4921 static int yaffs_DoXMod(yaffs_Object *obj, int set, const YCHAR *name, const void *value, int size, int flags)
4922 {
4923         yaffs_XAttrMod xmod;
4924
4925         int result;
4926
4927         xmod.set = set;
4928         xmod.name = name;
4929         xmod.data = value;
4930         xmod.size =  size;
4931         xmod.flags = flags;
4932         xmod.result = -ENOSPC;
4933
4934         result = yaffs_UpdateObjectHeader(obj, NULL, 0, 0, 0, &xmod);
4935
4936         if(result > 0)
4937                 return xmod.result;
4938         else
4939                 return -ENOSPC;
4940 }
4941
4942 static int yaffs_ApplyXMod(yaffs_Device *dev, char *buffer, yaffs_XAttrMod *xmod)
4943 {
4944         int retval = 0;
4945         int x_offs = sizeof(yaffs_ObjectHeader);
4946         int x_size = dev->nDataBytesPerChunk - sizeof(yaffs_ObjectHeader);
4947
4948         char * x_buffer = buffer + x_offs;
4949
4950         if(xmod->set)
4951                 retval = nval_set(x_buffer, x_size, xmod->name, xmod->data, xmod->size, xmod->flags);
4952         else
4953                 retval = nval_del(x_buffer, x_size, xmod->name);
4954
4955         xmod->result = retval;
4956
4957         return retval;
4958 }
4959
4960 static int yaffs_DoXFetch(yaffs_Object *obj, const YCHAR *name, void *value, int size)
4961 {
4962         char *buffer = NULL;
4963         int result;
4964         yaffs_ExtendedTags tags;
4965         yaffs_Device *dev = obj->myDev;
4966         int x_offs = sizeof(yaffs_ObjectHeader);
4967         int x_size = dev->nDataBytesPerChunk - sizeof(yaffs_ObjectHeader);
4968
4969         __u8 * x_buffer;
4970
4971         int retval = 0;
4972
4973         if(obj->hdrChunk < 1)
4974                 return -ENODATA;
4975
4976         buffer = yaffs_GetTempBuffer(dev, __LINE__);
4977         if(!buffer)
4978                 return -ENOMEM;
4979
4980         result = yaffs_ReadChunkWithTagsFromNAND(dev,obj->hdrChunk, buffer, &tags);
4981
4982         if(result != YAFFS_OK)
4983                 retval = -ENOENT;
4984         else{
4985                 x_buffer =  buffer + x_offs;
4986
4987                 if(name)
4988                         retval = nval_get(x_buffer, x_size, name, value, size);
4989                 else
4990                         retval = nval_list(x_buffer, x_size, value,size);
4991         }
4992         yaffs_ReleaseTempBuffer(dev,buffer,__LINE__);
4993         return retval;
4994 }
4995
4996 int yaffs_SetXAttribute(yaffs_Object *obj, const YCHAR *name, const void * value, int size, int flags)
4997 {
4998         return yaffs_DoXMod(obj, 1, name, value, size, flags);
4999 }
5000
5001 int yaffs_RemoveXAttribute(yaffs_Object *obj, const YCHAR *name)
5002 {
5003         return yaffs_DoXMod(obj, 0, name, NULL, 0, 0);
5004 }
5005
5006 int yaffs_GetXAttribute(yaffs_Object *obj, const YCHAR *name, void *value, int size)
5007 {
5008         return yaffs_DoXFetch(obj, name, value, size);
5009 }
5010
5011 int yaffs_ListXAttributes(yaffs_Object *obj, char *buffer, int size)
5012 {
5013         return yaffs_DoXFetch(obj, NULL, buffer,size);
5014 }
5015
5016
5017
5018 #if 0
5019 int yaffs_DumpObject(yaffs_Object *obj)
5020 {
5021         YCHAR name[257];
5022
5023         yaffs_GetObjectName(obj, name, YAFFS_MAX_NAME_LENGTH + 1);
5024
5025         T(YAFFS_TRACE_ALWAYS,
5026           (TSTR
5027            ("Object %d, inode %d \"%s\"\n dirty %d valid %d serial %d sum %d"
5028             " chunk %d type %d size %d\n"
5029             TENDSTR), obj->objectId, yaffs_GetObjectInode(obj), name,
5030            obj->dirty, obj->valid, obj->serial, obj->sum, obj->hdrChunk,
5031            yaffs_GetObjectType(obj), yaffs_GetObjectFileLength(obj)));
5032
5033         return YAFFS_OK;
5034 }
5035 #endif
5036
5037 /*---------------------------- Initialisation code -------------------------------------- */
5038
5039 static int yaffs_CheckDevFunctions(const yaffs_Device *dev)
5040 {
5041
5042         /* Common functions, gotta have */
5043         if (!dev->param.eraseBlockInNAND || !dev->param.initialiseNAND)
5044                 return 0;
5045
5046 #ifdef CONFIG_YAFFS_YAFFS2
5047
5048         /* Can use the "with tags" style interface for yaffs1 or yaffs2 */
5049         if (dev->param.writeChunkWithTagsToNAND &&
5050             dev->param.readChunkWithTagsFromNAND &&
5051             !dev->param.writeChunkToNAND &&
5052             !dev->param.readChunkFromNAND &&
5053             dev->param.markNANDBlockBad &&
5054             dev->param.queryNANDBlock)
5055                 return 1;
5056 #endif
5057
5058         /* Can use the "spare" style interface for yaffs1 */
5059         if (!dev->param.isYaffs2 &&
5060             !dev->param.writeChunkWithTagsToNAND &&
5061             !dev->param.readChunkWithTagsFromNAND &&
5062             dev->param.writeChunkToNAND &&
5063             dev->param.readChunkFromNAND &&
5064             !dev->param.markNANDBlockBad &&
5065             !dev->param.queryNANDBlock)
5066                 return 1;
5067
5068         return 0;       /* bad */
5069 }
5070
5071
5072 static int yaffs_CreateInitialDirectories(yaffs_Device *dev)
5073 {
5074         /* Initialise the unlinked, deleted, root and lost and found directories */
5075
5076         dev->lostNFoundDir = dev->rootDir =  NULL;
5077         dev->unlinkedDir = dev->deletedDir = NULL;
5078
5079         dev->unlinkedDir =
5080             yaffs_CreateFakeDirectory(dev, YAFFS_OBJECTID_UNLINKED, S_IFDIR);
5081
5082         dev->deletedDir =
5083             yaffs_CreateFakeDirectory(dev, YAFFS_OBJECTID_DELETED, S_IFDIR);
5084
5085         dev->rootDir =
5086             yaffs_CreateFakeDirectory(dev, YAFFS_OBJECTID_ROOT,
5087                                       YAFFS_ROOT_MODE | S_IFDIR);
5088         dev->lostNFoundDir =
5089             yaffs_CreateFakeDirectory(dev, YAFFS_OBJECTID_LOSTNFOUND,
5090                                       YAFFS_LOSTNFOUND_MODE | S_IFDIR);
5091
5092         if (dev->lostNFoundDir && dev->rootDir && dev->unlinkedDir && dev->deletedDir) {
5093                 yaffs_AddObjectToDirectory(dev->rootDir, dev->lostNFoundDir);
5094                 return YAFFS_OK;
5095         }
5096
5097         return YAFFS_FAIL;
5098 }
5099
5100 int yaffs_GutsInitialise(yaffs_Device *dev)
5101 {
5102         int init_failed = 0;
5103         unsigned x;
5104         int bits;
5105
5106         T(YAFFS_TRACE_TRACING, (TSTR("yaffs: yaffs_GutsInitialise()" TENDSTR)));
5107
5108         /* Check stuff that must be set */
5109
5110         if (!dev) {
5111                 T(YAFFS_TRACE_ALWAYS, (TSTR("yaffs: Need a device" TENDSTR)));
5112                 return YAFFS_FAIL;
5113         }
5114
5115         dev->internalStartBlock = dev->param.startBlock;
5116         dev->internalEndBlock = dev->param.endBlock;
5117         dev->blockOffset = 0;
5118         dev->chunkOffset = 0;
5119         dev->nFreeChunks = 0;
5120
5121         dev->gcBlock = 0;
5122
5123         if (dev->param.startBlock == 0) {
5124                 dev->internalStartBlock = dev->param.startBlock + 1;
5125                 dev->internalEndBlock = dev->param.endBlock + 1;
5126                 dev->blockOffset = 1;
5127                 dev->chunkOffset = dev->param.nChunksPerBlock;
5128         }
5129
5130         /* Check geometry parameters. */
5131
5132         if ((!dev->param.inbandTags && dev->param.isYaffs2 && dev->param.totalBytesPerChunk < 1024) ||
5133             (!dev->param.isYaffs2 && dev->param.totalBytesPerChunk < 512) ||
5134             (dev->param.inbandTags && !dev->param.isYaffs2) ||
5135              dev->param.nChunksPerBlock < 2 ||
5136              dev->param.nReservedBlocks < 2 ||
5137              dev->internalStartBlock <= 0 ||
5138              dev->internalEndBlock <= 0 ||
5139              dev->internalEndBlock <= (dev->internalStartBlock + dev->param.nReservedBlocks + 2)) {     /* otherwise it is too small */
5140                 T(YAFFS_TRACE_ALWAYS,
5141                   (TSTR
5142                    ("yaffs: NAND geometry problems: chunk size %d, type is yaffs%s, inbandTags %d "
5143                     TENDSTR), dev->param.totalBytesPerChunk, dev->param.isYaffs2 ? "2" : "", dev->param.inbandTags));
5144                 return YAFFS_FAIL;
5145         }
5146
5147         if (yaffs_InitialiseNAND(dev) != YAFFS_OK) {
5148                 T(YAFFS_TRACE_ALWAYS,
5149                   (TSTR("yaffs: InitialiseNAND failed" TENDSTR)));
5150                 return YAFFS_FAIL;
5151         }
5152
5153         /* Sort out space for inband tags, if required */
5154         if (dev->param.inbandTags)
5155                 dev->nDataBytesPerChunk = dev->param.totalBytesPerChunk - sizeof(yaffs_PackedTags2TagsPart);
5156         else
5157                 dev->nDataBytesPerChunk = dev->param.totalBytesPerChunk;
5158
5159         /* Got the right mix of functions? */
5160         if (!yaffs_CheckDevFunctions(dev)) {
5161                 /* Function missing */
5162                 T(YAFFS_TRACE_ALWAYS,
5163                   (TSTR
5164                    ("yaffs: device function(s) missing or wrong\n" TENDSTR)));
5165
5166                 return YAFFS_FAIL;
5167         }
5168
5169         /* This is really a compilation check. */
5170         if (!yaffs_CheckStructures()) {
5171                 T(YAFFS_TRACE_ALWAYS,
5172                   (TSTR("yaffs_CheckStructures failed\n" TENDSTR)));
5173                 return YAFFS_FAIL;
5174         }
5175
5176         if (dev->isMounted) {
5177                 T(YAFFS_TRACE_ALWAYS,
5178                   (TSTR("yaffs: device already mounted\n" TENDSTR)));
5179                 return YAFFS_FAIL;
5180         }
5181
5182         /* Finished with most checks. One or two more checks happen later on too. */
5183
5184         dev->isMounted = 1;
5185
5186         /* OK now calculate a few things for the device */
5187
5188         /*
5189          *  Calculate all the chunk size manipulation numbers:
5190          */
5191         x = dev->nDataBytesPerChunk;
5192         /* We always use dev->chunkShift and dev->chunkDiv */
5193         dev->chunkShift = Shifts(x);
5194         x >>= dev->chunkShift;
5195         dev->chunkDiv = x;
5196         /* We only use chunk mask if chunkDiv is 1 */
5197         dev->chunkMask = (1<<dev->chunkShift) - 1;
5198
5199         /*
5200          * Calculate chunkGroupBits.
5201          * We need to find the next power of 2 > than internalEndBlock
5202          */
5203
5204         x = dev->param.nChunksPerBlock * (dev->internalEndBlock + 1);
5205
5206         bits = ShiftsGE(x);
5207
5208         /* Set up tnode width if wide tnodes are enabled. */
5209         if (!dev->param.wideTnodesDisabled) {
5210                 /* bits must be even so that we end up with 32-bit words */
5211                 if (bits & 1)
5212                         bits++;
5213                 if (bits < 16)
5214                         dev->tnodeWidth = 16;
5215                 else
5216                         dev->tnodeWidth = bits;
5217         } else
5218                 dev->tnodeWidth = 16;
5219
5220         dev->tnodeMask = (1<<dev->tnodeWidth)-1;
5221
5222         /* Level0 Tnodes are 16 bits or wider (if wide tnodes are enabled),
5223          * so if the bitwidth of the
5224          * chunk range we're using is greater than 16 we need
5225          * to figure out chunk shift and chunkGroupSize
5226          */
5227
5228         if (bits <= dev->tnodeWidth)
5229                 dev->chunkGroupBits = 0;
5230         else
5231                 dev->chunkGroupBits = bits - dev->tnodeWidth;
5232
5233         dev->tnodeSize = (dev->tnodeWidth * YAFFS_NTNODES_LEVEL0)/8;
5234         if(dev->tnodeSize < sizeof(yaffs_Tnode))
5235                 dev->tnodeSize = sizeof(yaffs_Tnode);
5236
5237         dev->chunkGroupSize = 1 << dev->chunkGroupBits;
5238
5239         if (dev->param.nChunksPerBlock < dev->chunkGroupSize) {
5240                 /* We have a problem because the soft delete won't work if
5241                  * the chunk group size > chunks per block.
5242                  * This can be remedied by using larger "virtual blocks".
5243                  */
5244                 T(YAFFS_TRACE_ALWAYS,
5245                   (TSTR("yaffs: chunk group too large\n" TENDSTR)));
5246
5247                 return YAFFS_FAIL;
5248         }
5249
5250         /* OK, we've finished verifying the device, lets continue with initialisation */
5251
5252         /* More device initialisation */
5253         dev->allGCs = 0;
5254         dev->passiveGCs = 0;
5255         dev->oldestDirtyGCs = 0;
5256         dev->backgroundGCs = 0;
5257         dev->gcBlockFinder = 0;
5258         dev->bufferedBlock = -1;
5259         dev->doingBufferedBlockRewrite = 0;
5260         dev->nDeletedFiles = 0;
5261         dev->nBackgroundDeletions = 0;
5262         dev->nUnlinkedFiles = 0;
5263         dev->eccFixed = 0;
5264         dev->eccUnfixed = 0;
5265         dev->tagsEccFixed = 0;
5266         dev->tagsEccUnfixed = 0;
5267         dev->nErasureFailures = 0;
5268         dev->nErasedBlocks = 0;
5269         dev->gcDisable= 0;
5270         dev->hasPendingPrioritisedGCs = 1; /* Assume the worst for now, will get fixed on first GC */
5271         YINIT_LIST_HEAD(&dev->dirtyDirectories);
5272         dev->oldestDirtySequence = 0;
5273         dev->oldestDirtyBlock = 0;
5274
5275         /* Initialise temporary buffers and caches. */
5276         if (!yaffs_InitialiseTempBuffers(dev))
5277                 init_failed = 1;
5278
5279         dev->srCache = NULL;
5280         dev->gcCleanupList = NULL;
5281
5282
5283         if (!init_failed &&
5284             dev->param.nShortOpCaches > 0) {
5285                 int i;
5286                 void *buf;
5287                 int srCacheBytes = dev->param.nShortOpCaches * sizeof(yaffs_ChunkCache);
5288
5289                 if (dev->param.nShortOpCaches > YAFFS_MAX_SHORT_OP_CACHES)
5290                         dev->param.nShortOpCaches = YAFFS_MAX_SHORT_OP_CACHES;
5291
5292                 dev->srCache =  YMALLOC(srCacheBytes);
5293
5294                 buf = (__u8 *) dev->srCache;
5295
5296                 if (dev->srCache)
5297                         memset(dev->srCache, 0, srCacheBytes);
5298
5299                 for (i = 0; i < dev->param.nShortOpCaches && buf; i++) {
5300                         dev->srCache[i].object = NULL;
5301                         dev->srCache[i].lastUse = 0;
5302                         dev->srCache[i].dirty = 0;
5303                         dev->srCache[i].data = buf = YMALLOC_DMA(dev->param.totalBytesPerChunk);
5304                 }
5305                 if (!buf)
5306                         init_failed = 1;
5307
5308                 dev->srLastUse = 0;
5309         }
5310
5311         dev->cacheHits = 0;
5312
5313         if (!init_failed) {
5314                 dev->gcCleanupList = YMALLOC(dev->param.nChunksPerBlock * sizeof(__u32));
5315                 if (!dev->gcCleanupList)
5316                         init_failed = 1;
5317         }
5318
5319         if (dev->param.isYaffs2)
5320                 dev->param.useHeaderFileSize = 1;
5321
5322         if (!init_failed && !yaffs_InitialiseBlocks(dev))
5323                 init_failed = 1;
5324
5325         yaffs_InitialiseTnodesAndObjects(dev);
5326
5327         if (!init_failed && !yaffs_CreateInitialDirectories(dev))
5328                 init_failed = 1;
5329
5330
5331         if (!init_failed) {
5332                 /* Now scan the flash. */
5333                 if (dev->param.isYaffs2) {
5334                         if (yaffs2_CheckpointRestore(dev)) {
5335                                 yaffs_CheckObjectDetailsLoaded(dev->rootDir);
5336                                 T(YAFFS_TRACE_ALWAYS,
5337                                   (TSTR("yaffs: restored from checkpoint" TENDSTR)));
5338                         } else {
5339
5340                                 /* Clean up the mess caused by an aborted checkpoint load
5341                                  * and scan backwards.
5342                                  */
5343                                 yaffs_DeinitialiseBlocks(dev);
5344
5345                                 yaffs_DeinitialiseTnodesAndObjects(dev);
5346
5347                                 dev->nErasedBlocks = 0;
5348                                 dev->nFreeChunks = 0;
5349                                 dev->allocationBlock = -1;
5350                                 dev->allocationPage = -1;
5351                                 dev->nDeletedFiles = 0;
5352                                 dev->nUnlinkedFiles = 0;
5353                                 dev->nBackgroundDeletions = 0;
5354
5355                                 if (!init_failed && !yaffs_InitialiseBlocks(dev))
5356                                         init_failed = 1;
5357
5358                                 yaffs_InitialiseTnodesAndObjects(dev);
5359
5360                                 if (!init_failed && !yaffs_CreateInitialDirectories(dev))
5361                                         init_failed = 1;
5362
5363                                 if (!init_failed && !yaffs2_ScanBackwards(dev))
5364                                         init_failed = 1;
5365                         }
5366                 } else if (!yaffs1_Scan(dev))
5367                                 init_failed = 1;
5368
5369                 yaffs_StripDeletedObjects(dev);
5370                 yaffs_FixHangingObjects(dev);
5371                 if(dev->param.emptyLostAndFound)
5372                         yaffs_EmptyLostAndFound(dev);
5373         }
5374
5375         if (init_failed) {
5376                 /* Clean up the mess */
5377                 T(YAFFS_TRACE_TRACING,
5378                   (TSTR("yaffs: yaffs_GutsInitialise() aborted.\n" TENDSTR)));
5379
5380                 yaffs_Deinitialise(dev);
5381                 return YAFFS_FAIL;
5382         }
5383
5384         /* Zero out stats */
5385         dev->nPageReads = 0;
5386         dev->nPageWrites = 0;
5387         dev->nBlockErasures = 0;
5388         dev->nGCCopies = 0;
5389         dev->nRetriedWrites = 0;
5390
5391         dev->nRetiredBlocks = 0;
5392
5393         yaffs_VerifyFreeChunks(dev);
5394         yaffs_VerifyBlocks(dev);
5395
5396         /* Clean up any aborted checkpoint data */
5397         if(!dev->isCheckpointed && dev->blocksInCheckpoint > 0)
5398                 yaffs2_InvalidateCheckpoint(dev);
5399
5400         T(YAFFS_TRACE_TRACING,
5401           (TSTR("yaffs: yaffs_GutsInitialise() done.\n" TENDSTR)));
5402         return YAFFS_OK;
5403
5404 }
5405
5406 void yaffs_Deinitialise(yaffs_Device *dev)
5407 {
5408         if (dev->isMounted) {
5409                 int i;
5410
5411                 yaffs_DeinitialiseBlocks(dev);
5412                 yaffs_DeinitialiseTnodesAndObjects(dev);
5413                 if (dev->param.nShortOpCaches > 0 &&
5414                     dev->srCache) {
5415
5416                         for (i = 0; i < dev->param.nShortOpCaches; i++) {
5417                                 if (dev->srCache[i].data)
5418                                         YFREE(dev->srCache[i].data);
5419                                 dev->srCache[i].data = NULL;
5420                         }
5421
5422                         YFREE(dev->srCache);
5423                         dev->srCache = NULL;
5424                 }
5425
5426                 YFREE(dev->gcCleanupList);
5427
5428                 for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++)
5429                         YFREE(dev->tempBuffer[i].buffer);
5430
5431                 dev->isMounted = 0;
5432
5433                 if (dev->param.deinitialiseNAND)
5434                         dev->param.deinitialiseNAND(dev);
5435         }
5436 }
5437
5438 int yaffs_CountFreeChunks(yaffs_Device *dev)
5439 {
5440         int nFree=0;
5441         int b;
5442
5443         yaffs_BlockInfo *blk;
5444
5445         blk = dev->blockInfo;
5446         for (b = dev->internalStartBlock; b <= dev->internalEndBlock; b++) {
5447                 switch (blk->blockState) {
5448                 case YAFFS_BLOCK_STATE_EMPTY:
5449                 case YAFFS_BLOCK_STATE_ALLOCATING:
5450                 case YAFFS_BLOCK_STATE_COLLECTING:
5451                 case YAFFS_BLOCK_STATE_FULL:
5452                         nFree +=
5453                             (dev->param.nChunksPerBlock - blk->pagesInUse +
5454                              blk->softDeletions);
5455                         break;
5456                 default:
5457                         break;
5458                 }
5459                 blk++;
5460         }
5461
5462         return nFree;
5463 }
5464
5465 int yaffs_GetNumberOfFreeChunks(yaffs_Device *dev)
5466 {
5467         /* This is what we report to the outside world */
5468
5469         int nFree;
5470         int nDirtyCacheChunks;
5471         int blocksForCheckpoint;
5472         int i;
5473
5474 #if 1
5475         nFree = dev->nFreeChunks;
5476 #else
5477         nFree = yaffs_CountFreeChunks(dev);
5478 #endif
5479
5480         nFree += dev->nDeletedFiles;
5481
5482         /* Now count the number of dirty chunks in the cache and subtract those */
5483
5484         for (nDirtyCacheChunks = 0, i = 0; i < dev->param.nShortOpCaches; i++) {
5485                 if (dev->srCache[i].dirty)
5486                         nDirtyCacheChunks++;
5487         }
5488
5489         nFree -= nDirtyCacheChunks;
5490
5491         nFree -= ((dev->param.nReservedBlocks + 1) * dev->param.nChunksPerBlock);
5492
5493         /* Now we figure out how much to reserve for the checkpoint and report that... */
5494         blocksForCheckpoint = yaffs2_CalcCheckpointBlocksRequired(dev);
5495
5496         nFree -= (blocksForCheckpoint * dev->param.nChunksPerBlock);
5497
5498         if (nFree < 0)
5499                 nFree = 0;
5500
5501         return nFree;
5502
5503 }
5504
5505
5506 /*---------------------------------------- YAFFS test code ----------------------*/
5507
5508 #define yaffs_CheckStruct(structure, syze, name) \
5509         do { \
5510                 if (sizeof(structure) != syze) { \
5511                         T(YAFFS_TRACE_ALWAYS, (TSTR("%s should be %d but is %d\n" TENDSTR),\
5512                                 name, syze, (int) sizeof(structure))); \
5513                         return YAFFS_FAIL; \
5514                 } \
5515         } while (0)
5516
5517 static int yaffs_CheckStructures(void)
5518 {
5519 /*      yaffs_CheckStruct(yaffs_Tags,8,"yaffs_Tags"); */
5520 /*      yaffs_CheckStruct(yaffs_TagsUnion,8,"yaffs_TagsUnion"); */
5521 /*      yaffs_CheckStruct(yaffs_Spare,16,"yaffs_Spare"); */
5522 #ifndef CONFIG_YAFFS_TNODE_LIST_DEBUG
5523 /*      yaffs_CheckStruct(yaffs_Tnode, 2 * YAFFS_NTNODES_LEVEL0, "yaffs_Tnode"); */
5524 #endif
5525 #ifndef CONFIG_YAFFS_WINCE
5526         yaffs_CheckStruct(yaffs_ObjectHeader, 512, "yaffs_ObjectHeader");
5527 #endif
5528         return YAFFS_OK;
5529 }