yaffs_guts.c

   1 /*
   2  * YAFFS: Yet another FFS. A NAND-flash specific file system.
   3  * yaffs_guts.c  The main guts of YAFFS
   4  *
   5  * Copyright (C) 2002 Aleph One Ltd.
   6  *   for Toby Churchill Ltd and Brightstar Engineering
   7  *
   8  * Created by Charles Manning <charles@aleph1.co.uk>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License version 2 as
  12  * published by the Free Software Foundation.
  13  *
  14  */
  15  //yaffs_guts.c
  16
  17 const char *yaffs_guts_c_version="$Id: yaffs_guts.c,v 1.36 2004-10-10 17:54:59 charles Exp $";
  18
  19 #include "yportenv.h"
  20
  21 #include "yaffsinterface.h"
  22 #include "yaffs_guts.h"
  23
  24 #define YAFFS_PASSIVE_GC_CHUNKS 2
  25
  26 #if 0
  27 // Use Steven Hill's ECC struff instead
  28 // External functions for ECC on data
  29 void nand_calculate_ecc (const u_char *dat, u_char *ecc_code);
  30 int nand_correct_data (u_char *dat, u_char *read_ecc, u_char *calc_ecc);
  31 #define yaffs_ECCCalculate(data,ecc) nand_calculate_ecc(data,ecc)
  32 #define yaffs_ECCCorrect(data,read_ecc,calc_ecc) nand_correct_ecc(data,read_ecc,calc_ecc)
  33 #else
  34 #include "yaffs_ecc.h"
  35 #endif
  36
  37 // countBits is a quick way of counting the number of bits in a byte.
  38 // ie. countBits[n] holds the number of 1 bits in a byte with the value n.
  39
  40 static const char yaffs_countBitsTable[256] =
  41 {
  42 0,1,1,2,1,2,2,3,1,2,2,3,2,3,3,4,
  43 1,2,2,3,2,3,3,4,2,3,3,4,3,4,4,5,
  44 1,2,2,3,2,3,3,4,2,3,3,4,3,4,4,5,
  45 2,3,3,4,3,4,4,5,3,4,4,5,4,5,5,6,
  46 1,2,2,3,2,3,3,4,2,3,3,4,3,4,4,5,
  47 2,3,3,4,3,4,4,5,3,4,4,5,4,5,5,6,
  48 2,3,3,4,3,4,4,5,3,4,4,5,4,5,5,6,
  49 3,4,4,5,4,5,5,6,4,5,5,6,5,6,6,7,
  50 1,2,2,3,2,3,3,4,2,3,3,4,3,4,4,5,
  51 2,3,3,4,3,4,4,5,3,4,4,5,4,5,5,6,
  52 2,3,3,4,3,4,4,5,3,4,4,5,4,5,5,6,
  53 3,4,4,5,4,5,5,6,4,5,5,6,5,6,6,7,
  54 2,3,3,4,3,4,4,5,3,4,4,5,4,5,5,6,
  55 3,4,4,5,4,5,5,6,4,5,5,6,5,6,6,7,
  56 3,4,4,5,4,5,5,6,4,5,5,6,5,6,6,7,
  57 4,5,5,6,5,6,6,7,5,6,6,7,6,7,7,8
  58 };
  59
  60 static int yaffs_CountBits(__u8 x)
  61 {
  62         int retVal;
  63         retVal = yaffs_countBitsTable[x];
  64         return retVal;
  65 }
  66
  67
  68
  69 // Local prototypes
  70 static int yaffs_CheckObjectHashSanity(yaffs_Device *dev);
  71 static void yaffs_LoadTagsIntoSpare(yaffs_Spare *sparePtr, yaffs_Tags *tagsPtr);
  72 static void yaffs_GetTagsFromSpare(yaffs_Device *dev, yaffs_Spare *sparePtr,yaffs_Tags *tagsPtr);
  73 static int yaffs_PutChunkIntoFile(yaffs_Object *in,int chunkInInode, int chunkInNAND, int inScan);
  74
  75 static yaffs_Object *yaffs_CreateNewObject(yaffs_Device *dev,int number,yaffs_ObjectType type);
  76 static void yaffs_AddObjectToDirectory(yaffs_Object *directory, yaffs_Object *obj);
  77 static int yaffs_UpdateObjectHeader(yaffs_Object *in,const char *name, int force);
  78 static void yaffs_DeleteChunk(yaffs_Device *dev,int chunkId,int markNAND);
  79 static void yaffs_RemoveObjectFromDirectory(yaffs_Object *obj);
  80 static int yaffs_CheckStructures(void);
  81 static int yaffs_DeleteWorker(yaffs_Object *in, yaffs_Tnode *tn, __u32 level, int chunkOffset,int *limit);
  82 static int yaffs_DoGenericObjectDeletion(yaffs_Object *in);
  83
  84 static yaffs_BlockInfo *yaffs_GetBlockInfo(yaffs_Device *dev,int blockNo);
  85
  86 // Robustification
  87 static void yaffs_RetireBlock(yaffs_Device *dev,int blockInNAND);
  88 static void yaffs_HandleReadDataError(yaffs_Device *dev,int chunkInNAND);
  89 static void yaffs_HandleWriteChunkError(yaffs_Device *dev,int chunkInNAND);
  90 static void yaffs_HandleWriteChunkOk(yaffs_Device *dev,int chunkInNAND,const __u8 *data, const yaffs_Spare *spare);
  91 static void yaffs_HandleUpdateChunk(yaffs_Device *dev,int chunkInNAND, const yaffs_Spare *spare);
  92
  93 static int  yaffs_CheckChunkErased(struct yaffs_DeviceStruct *dev,int chunkInNAND);
  94
  95 static int yaffs_UnlinkWorker(yaffs_Object *obj);
  96 static void yaffs_AbortHalfCreatedObject(yaffs_Object *obj);
  97
  98 static int yaffs_VerifyCompare(const __u8 *d0, const __u8 * d1, const yaffs_Spare *s0, const yaffs_Spare *s1);
  99
 100
 101
 102 loff_t yaffs_GetFileSize(yaffs_Object *obj);
 103
 104 static int yaffs_ReadChunkTagsFromNAND(yaffs_Device *dev,int chunkInNAND, yaffs_Tags *tags, int *chunkDeleted);
 105 static int yaffs_TagsMatch(const yaffs_Tags *tags, int objectId, int chunkInObject, int chunkDeleted);
 106
 107
 108 static int yaffs_AllocateChunk(yaffs_Device *dev,int useReserve);
 109
 110 #ifdef YAFFS_PARANOID
 111 static int yaffs_CheckFileSanity(yaffs_Object *in);
 112 #else
 113 #define yaffs_CheckFileSanity(in)
 114 #endif
 115
 116 static void yaffs_InvalidateWholeChunkCache(yaffs_Object *in);
 117 static void yaffs_InvalidateChunkCache(yaffs_Object *object, int chunkId);
 118
 119 // Chunk bitmap manipulations
 120
 121 static __inline __u8 *yaffs_BlockBits(yaffs_Device *dev, int blk)
 122 {
 123         if(blk < dev->startBlock || blk > dev->endBlock)
 124         {
 125                 T(YAFFS_TRACE_ERROR,(TSTR("**>> yaffs: BlockBits block %d is not valid" TENDSTR),blk));
 126                 YBUG();
 127         }
 128         return dev->chunkBits + (dev->chunkBitmapStride * (blk - dev->startBlock));
 129 }
 130
 131 static __inline__ void yaffs_ClearChunkBits(yaffs_Device *dev,int blk)
 132 {
 133         __u8 *blkBits = yaffs_BlockBits(dev,blk);
 134
 135          memset(blkBits,0,dev->chunkBitmapStride);
 136 }
 137
 138 static __inline__ void yaffs_ClearChunkBit(yaffs_Device *dev,int blk,int chunk)
 139 {
 140         __u8 *blkBits = yaffs_BlockBits(dev,blk);
 141
 142         blkBits[chunk/8] &=  ~ (1<<(chunk & 7));
 143 }
 144
 145 static __inline__ void yaffs_SetChunkBit(yaffs_Device *dev,int blk,int chunk)
 146 {
 147         __u8 *blkBits = yaffs_BlockBits(dev,blk);
 148
 149         blkBits[chunk/8] |=   (1<<(chunk & 7));
 150 }
 151
 152 static __inline__ int yaffs_CheckChunkBit(yaffs_Device *dev,int blk,int chunk)
 153 {
 154         __u8 *blkBits = yaffs_BlockBits(dev,blk);
 155         return (blkBits[chunk/8] &  (1<<(chunk & 7))) ? 1 :0;
 156 }
 157
 158 static __inline__ int yaffs_StillSomeChunkBits(yaffs_Device *dev,int blk)
 159 {
 160         __u8 *blkBits = yaffs_BlockBits(dev,blk);
 161         int i;
 162         for(i = 0; i < dev->chunkBitmapStride; i++)
 163         {
 164                 if(*blkBits) return 1;
 165                 blkBits++;
 166         }
 167         return 0;
 168 }
 169
 170 // Function to manipulate block info
 171 static  __inline__ yaffs_BlockInfo* yaffs_GetBlockInfo(yaffs_Device *dev, int blk)
 172 {
 173         if(blk < dev->startBlock || blk > dev->endBlock)
 174         {
 175                 T(YAFFS_TRACE_ERROR,(TSTR("**>> yaffs: getBlockInfo block %d is not valid" TENDSTR),blk));
 176                 YBUG();
 177         }
 178         return &dev->blockInfo[blk - dev->startBlock];
 179 }
 180
 181
 182 static  __inline__ int yaffs_HashFunction(int n)
 183 {
 184         return (n % YAFFS_NOBJECT_BUCKETS);
 185 }
 186
 187
 188 yaffs_Object *yaffs_Root(yaffs_Device *dev)
 189 {
 190         return dev->rootDir;
 191 }
 192
 193 yaffs_Object *yaffs_LostNFound(yaffs_Device *dev)
 194 {
 195         return dev->lostNFoundDir;
 196 }
 197
 198
 199 static int yaffs_WriteChunkToNAND(struct yaffs_DeviceStruct *dev,int chunkInNAND, const __u8 *data, yaffs_Spare *spare)
 200 {
 201         if(chunkInNAND < dev->startBlock * dev->nChunksPerBlock)
 202         {
 203                 T(YAFFS_TRACE_ERROR,(TSTR("**>> yaffs chunk %d is not valid" TENDSTR),chunkInNAND));
 204                 return YAFFS_FAIL;
 205         }
 206
 207         dev->nPageWrites++;
 208         return dev->writeChunkToNAND(dev,chunkInNAND,data,spare);
 209 }
 210
 211
 212
 213 int yaffs_ReadChunkFromNAND(struct yaffs_DeviceStruct *dev,
 214                                                         int chunkInNAND,
 215                                                         __u8 *data,
 216                                                         yaffs_Spare *spare,
 217                                                         int doErrorCorrection)
 218 {
 219         int retVal;
 220         yaffs_Spare localSpare;
 221
 222         dev->nPageReads++;
 223
 224
 225
 226
 227         if(!spare && data)
 228         {
 229                 // If we don't have a real spare, then we use a local one.
 230                 // Need this for the calculation of the ecc
 231                 spare = &localSpare;
 232         }
 233
 234
 235         if(!dev->useNANDECC)
 236         {
 237                 retVal  = dev->readChunkFromNAND(dev,chunkInNAND,data,spare);
 238                 if(data && doErrorCorrection)
 239                 {
 240                         // Do ECC correction
 241                         //Todo handle any errors
 242                 int eccResult1,eccResult2;
 243                 __u8 calcEcc[3];
 244
 245                         yaffs_ECCCalculate(data,calcEcc);
 246                         eccResult1 = yaffs_ECCCorrect (data,spare->ecc1, calcEcc);
 247                         yaffs_ECCCalculate(&data[256],calcEcc);
 248                         eccResult2 = yaffs_ECCCorrect(&data[256],spare->ecc2, calcEcc);
 249
 250                         if(eccResult1>0)
 251                         {
 252                                 T(YAFFS_TRACE_ERROR, (TSTR("**>>ecc error fix performed on chunk %d:0" TENDSTR),chunkInNAND));
 253                                 dev->eccFixed++;
 254                         }
 255                         else if(eccResult1<0)
 256                         {
 257                                 T(YAFFS_TRACE_ERROR,(TSTR("**>>ecc error unfixed on chunk %d:0" TENDSTR),chunkInNAND));
 258                                 dev->eccUnfixed++;
 259                         }
 260
 261                         if(eccResult2>0)
 262                         {
 263                                 T(YAFFS_TRACE_ERROR,(TSTR("**>>ecc error fix performed on chunk %d:1" TENDSTR),chunkInNAND));
 264                                 dev->eccFixed++;
 265                         }
 266                         else if(eccResult2<0)
 267                         {
 268                                 T(YAFFS_TRACE_ERROR,(TSTR("**>>ecc error unfixed on chunk %d:1" TENDSTR),chunkInNAND));
 269                                 dev->eccUnfixed++;
 270                         }
 271
 272                         if(eccResult1 || eccResult2)
 273                         {
 274                                 // Hoosterman, we had a data problem on this page
 275                                 yaffs_HandleReadDataError(dev,chunkInNAND);
 276                         }
 277                 }
 278         }
 279         else
 280         {
 281         // Must allocate enough memory for spare+2*sizeof(int) for ecc results from device.
 282         struct yaffs_NANDSpare nspare;
 283                 retVal  = dev->readChunkFromNAND(dev,chunkInNAND,data,(yaffs_Spare*)&nspare);
 284                 memcpy (spare, &nspare, sizeof(yaffs_Spare));
 285                 if(data && doErrorCorrection)
 286                 {
 287                         if(nspare.eccres1>0)
 288                         {
 289                                 T(YAFFS_TRACE_ERROR,(TSTR("**>>ecc error fix performed on chunk %d:0" TENDSTR),chunkInNAND));
 290                         }
 291                         else if(nspare.eccres1<0)
 292                         {
 293                                 T(YAFFS_TRACE_ERROR,(TSTR("**>>ecc error unfixed on chunk %d:0" TENDSTR),chunkInNAND));
 294                         }
 295
 296                         if(nspare.eccres2>0)
 297                         {
 298                                 T(YAFFS_TRACE_ERROR,(TSTR("**>>ecc error fix performed on chunk %d:1" TENDSTR),chunkInNAND));
 299                         }
 300                         else if(nspare.eccres2<0)
 301                         {
 302                                 T(YAFFS_TRACE_ERROR,(TSTR("**>>ecc error unfixed on chunk %d:1" TENDSTR),chunkInNAND));
 303                         }
 304
 305                         if(nspare.eccres1 || nspare.eccres2)
 306                         {
 307                                 // Hoosterman, we had a data problem on this page
 308                                 yaffs_HandleReadDataError(dev,chunkInNAND);
 309                         }
 310
 311                 }
 312         }
 313         return retVal;
 314 }
 315
 316
 317 static int yaffs_CheckChunkErased(struct yaffs_DeviceStruct *dev,int chunkInNAND)
 318 {
 319
 320         static int init = 0;
 321         static __u8 cmpbuf[YAFFS_BYTES_PER_CHUNK];
 322         static __u8 data[YAFFS_BYTES_PER_CHUNK];
 323     // Might as well always allocate the larger size for dev->useNANDECC == true;
 324         static __u8 spare[sizeof(struct yaffs_NANDSpare)];
 325
 326         dev->readChunkFromNAND(dev,chunkInNAND,data,(yaffs_Spare *)spare);
 327
 328         if(!init)
 329         {
 330                 memset(cmpbuf,0xff,YAFFS_BYTES_PER_CHUNK);
 331                 init = 1;
 332         }
 333
 334         if(memcmp(cmpbuf,data,YAFFS_BYTES_PER_CHUNK)) return  YAFFS_FAIL;
 335         if(memcmp(cmpbuf,spare,16)) return YAFFS_FAIL;
 336
 337
 338         return YAFFS_OK;
 339
 340 }
 341
 342
 343
 344 int yaffs_EraseBlockInNAND(struct yaffs_DeviceStruct *dev,int blockInNAND)
 345 {
 346         dev->nBlockErasures++;
 347         return dev->eraseBlockInNAND(dev,blockInNAND);
 348 }
 349
 350 int yaffs_InitialiseNAND(struct yaffs_DeviceStruct *dev)
 351 {
 352         return dev->initialiseNAND(dev);
 353 }
 354
 355 static int yaffs_WriteNewChunkToNAND(struct yaffs_DeviceStruct *dev, const __u8 *data, yaffs_Spare *spare,int useReserve)
 356 {
 357         int chunk;
 358
 359         int writeOk = 1;
 360         int attempts = 0;
 361
 362         unsigned char rbData[YAFFS_BYTES_PER_CHUNK];
 363         yaffs_Spare rbSpare;
 364
 365         do{
 366                 chunk = yaffs_AllocateChunk(dev,useReserve);
 367
 368                 if(chunk >= 0)
 369                 {
 370
 371                         // First check this chunk is erased...
 372 #ifndef CONFIG_YAFFS_DISABLE_CHUNK_ERASED_CHECK
 373                         writeOk = yaffs_CheckChunkErased(dev,chunk);
 374 #endif
 375                         if(!writeOk)
 376                         {
 377                                 T(YAFFS_TRACE_ERROR,(TSTR("**>> yaffs chunk %d was not erased" TENDSTR),chunk));
 378                         }
 379                         else
 380                         {
 381                                 writeOk =  yaffs_WriteChunkToNAND(dev,chunk,data,spare);
 382                         }
 383                         attempts++;
 384                         if(writeOk)
 385                         {
 386                                 // Readback & verify
 387                                 // If verify fails, then delete this chunk and try again
 388                                 // To verify we compare everything except the block and
 389                                 // page status bytes.
 390                                 // NB We check a raw read without ECC correction applied
 391                                 yaffs_ReadChunkFromNAND(dev,chunk,rbData,&rbSpare,0);
 392
 393 #ifndef CONFIG_YAFFS_DISABLE_WRITE_VERIFY
 394                                 if(!yaffs_VerifyCompare(data,rbData,spare,&rbSpare))
 395                                 {
 396                                         // Didn't verify
 397                                         T(YAFFS_TRACE_ERROR,(TSTR("**>> yaffs write verify failed on chunk %d" TENDSTR), chunk));
 398
 399                                         writeOk = 0;
 400                                 }
 401 #endif
 402
 403                         }
 404                         if(writeOk)
 405                         {
 406                                 // Copy the data into the write buffer.
 407                                 // NB We do this at the end to prevent duplicates in the case of a write error.
 408                                 //Todo
 409                                 yaffs_HandleWriteChunkOk(dev,chunk,data,spare);
 410                         }
 411                         else
 412                         {
 413                                 yaffs_HandleWriteChunkError(dev,chunk);
 414                         }
 415                 }
 416
 417         } while(chunk >= 0 && ! writeOk);
 418
 419         if(attempts > 1)
 420         {
 421                 T(YAFFS_TRACE_ERROR,(TSTR("**>> yaffs write required %d attempts" TENDSTR),attempts));
 422                 dev->nRetriedWrites+= (attempts - 1);
 423         }
 424
 425         return chunk;
 426 }
 427
 428 ///
 429 // Functions for robustisizing
 430 //
 431 //
 432
 433 static void yaffs_RetireBlock(yaffs_Device *dev,int blockInNAND)
 434 {
 435         // Ding the blockStatus in the first two pages of the block.
 436
 437         yaffs_Spare spare;
 438
 439         memset(&spare, 0xff,sizeof(yaffs_Spare));
 440
 441         spare.blockStatus = 0;
 442
 443         // TODO change this retirement marking for other NAND types
 444         yaffs_WriteChunkToNAND(dev, blockInNAND * dev->nChunksPerBlock, NULL , &spare);
 445         yaffs_WriteChunkToNAND(dev, blockInNAND * dev->nChunksPerBlock + 1, NULL , &spare);
 446
 447         yaffs_GetBlockInfo(dev,blockInNAND)->blockState = YAFFS_BLOCK_STATE_DEAD;
 448         dev->nRetiredBlocks++;
 449 }
 450
 451
 452
 453 static int yaffs_RewriteBufferedBlock(yaffs_Device *dev)
 454 {
 455         dev->doingBufferedBlockRewrite = 1;
 456         //
 457         //      Remove erased chunks
 458         //  Rewrite existing chunks to a new block
 459         //      Set current write block to the new block
 460
 461         dev->doingBufferedBlockRewrite = 0;
 462
 463         return 1;
 464 }
 465
 466
 467 static void yaffs_HandleReadDataError(yaffs_Device *dev,int chunkInNAND)
 468 {
 469         int blockInNAND = chunkInNAND/dev->nChunksPerBlock;
 470
 471         // Mark the block for retirement
 472         yaffs_GetBlockInfo(dev,blockInNAND)->needsRetiring = 1;
 473         T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,(TSTR("**>>Block %d marked for retirement" TENDSTR),blockInNAND));
 474
 475
 476         //TODO
 477         // Just do a garbage collection on the affected block then retire the block
 478         // NB recursion
 479 }
 480
 481
 482 static void yaffs_CheckWrittenBlock(yaffs_Device *dev,int chunkInNAND)
 483 {
 484 }
 485
 486 static void yaffs_HandleWriteChunkOk(yaffs_Device *dev,int chunkInNAND,const __u8 *data, const yaffs_Spare *spare)
 487 {
 488 }
 489
 490 static void yaffs_HandleUpdateChunk(yaffs_Device *dev,int chunkInNAND, const yaffs_Spare *spare)
 491 {
 492 }
 493
 494 static void yaffs_HandleWriteChunkError(yaffs_Device *dev,int chunkInNAND)
 495 {
 496         int blockInNAND = chunkInNAND/dev->nChunksPerBlock;
 497
 498         // Mark the block for retirement
 499         yaffs_GetBlockInfo(dev,blockInNAND)->needsRetiring = 1;
 500         // Delete the chunk
 501         yaffs_DeleteChunk(dev,chunkInNAND,1);
 502 }
 503
 504
 505
 506
 507 static int yaffs_VerifyCompare(const __u8 *d0, const __u8 * d1, const yaffs_Spare *s0, const yaffs_Spare *s1)
 508 {
 509
 510
 511         if( memcmp(d0,d1,YAFFS_BYTES_PER_CHUNK) != 0 ||
 512                 s0->tagByte0 != s1->tagByte0 ||
 513                 s0->tagByte1 != s1->tagByte1 ||
 514                 s0->tagByte2 != s1->tagByte2 ||
 515                 s0->tagByte3 != s1->tagByte3 ||
 516                 s0->tagByte4 != s1->tagByte4 ||
 517                 s0->tagByte5 != s1->tagByte5 ||
 518                 s0->tagByte6 != s1->tagByte6 ||
 519                 s0->tagByte7 != s1->tagByte7 ||
 520                 s0->ecc1[0]  != s1->ecc1[0]  ||
 521                 s0->ecc1[1]  != s1->ecc1[1]  ||
 522                 s0->ecc1[2]  != s1->ecc1[2]  ||
 523                 s0->ecc2[0]  != s1->ecc2[0]  ||
 524                 s0->ecc2[1]  != s1->ecc2[1]  ||
 525                 s0->ecc2[2]  != s1->ecc2[2] )
 526                 {
 527                         return 0;
 528                 }
 529
 530         return 1;
 531 }
 532
 533
 534 ///////////////////////// Object management //////////////////
 535 // List of spare objects
 536 // The list is hooked together using the first pointer
 537 // in the object
 538
 539 // static yaffs_Object *yaffs_freeObjects = NULL;
 540
 541 // static int yaffs_nFreeObjects;
 542
 543 // static yaffs_ObjectList *yaffs_allocatedObjectList = NULL;
 544
 545 // static yaffs_ObjectBucket yaffs_objectBucket[YAFFS_NOBJECT_BUCKETS];
 546
 547
 548 static __u16 yaffs_CalcNameSum(const char *name)
 549 {
 550         __u16 sum = 0;
 551         __u16 i = 1;
 552
 553         __u8 *bname = (__u8 *)name;
 554         if(bname)
 555         {
 556                 while ((*bname) && (i <=YAFFS_MAX_NAME_LENGTH))
 557                 {
 558
 559 #ifdef CONFIG_YAFFS_CASE_INSENSITIVE
 560                         sum += toupper(*bname) * i;
 561 #else
 562                         sum += (*bname) * i;
 563 #endif
 564                         i++;
 565                         bname++;
 566                 }
 567         }
 568         return sum;
 569 }
 570
 571 void yaffs_SetObjectName(yaffs_Object *obj, const char *name)
 572 {
 573 #ifdef CONFIG_YAFFS_SHORT_NAMES_IN_RAM
 574                                         if(name && strlen(name) <= YAFFS_SHORT_NAME_LENGTH)
 575                                         {
 576                                                 strcpy(obj->shortName,name);
 577                                         }
 578                                         else
 579                                         {
 580                                                 obj->shortName[0]='\0';
 581                                         }
 582 #endif
 583                                         obj->sum = yaffs_CalcNameSum(name);
 584 }
 585
 586 void yaffs_CalcECC(const __u8 *data, yaffs_Spare *spare)
 587 {
 588         yaffs_ECCCalculate(data , spare->ecc1);
 589         yaffs_ECCCalculate(&data[256] , spare->ecc2);
 590 }
 591
 592 void yaffs_CalcTagsECC(yaffs_Tags *tags)
 593 {
 594         // Calculate an ecc
 595
 596         unsigned char *b = ((yaffs_TagsUnion *)tags)->asBytes;
 597         unsigned  i,j;
 598         unsigned  ecc = 0;
 599         unsigned bit = 0;
 600
 601         tags->ecc = 0;
 602
 603         for(i = 0; i < 8; i++)
 604         {
 605                 for(j = 1; j &0xff; j<<=1)
 606                 {
 607                         bit++;
 608                         if(b[i] & j)
 609                         {
 610                                 ecc ^= bit;
 611                         }
 612                 }
 613         }
 614
 615         tags->ecc = ecc;
 616
 617
 618 }
 619
 620 int  yaffs_CheckECCOnTags(yaffs_Tags *tags)
 621 {
 622         unsigned ecc = tags->ecc;
 623
 624         yaffs_CalcTagsECC(tags);
 625
 626         ecc ^= tags->ecc;
 627
 628         if(ecc && ecc <= 64)
 629         {
 630                 // TODO: Handle the failure better. Retire?
 631                 unsigned char *b = ((yaffs_TagsUnion *)tags)->asBytes;
 632
 633                 ecc--;
 634
 635                 b[ecc / 8] ^= (1 << (ecc & 7));
 636
 637                 // Now recvalc the ecc
 638                 yaffs_CalcTagsECC(tags);
 639
 640                 return 1; // recovered error
 641         }
 642         else if(ecc)
 643         {
 644                 // Wierd ecc failure value
 645                 // TODO Need to do somethiong here
 646                 return -1; //unrecovered error
 647         }
 648
 649         return 0;
 650 }
 651
 652
 653 ///////////////////////// TNODES ///////////////////////
 654
 655 // List of spare tnodes
 656 // The list is hooked together using the first pointer
 657 // in the tnode.
 658
 659 //static yaffs_Tnode *yaffs_freeTnodes = NULL;
 660
 661 // static int yaffs_nFreeTnodes;
 662
 663 //static yaffs_TnodeList *yaffs_allocatedTnodeList = NULL;
 664
 665
 666
 667 // yaffs_CreateTnodes creates a bunch more tnodes and
 668 // adds them to the tnode free list.
 669 // Don't use this function directly
 670
 671 static int yaffs_CreateTnodes(yaffs_Device *dev,int nTnodes)
 672 {
 673     int i;
 674     yaffs_Tnode *newTnodes;
 675     yaffs_TnodeList *tnl;
 676
 677     if(nTnodes < 1) return YAFFS_OK;
 678
 679         // make these things
 680
 681     newTnodes = YMALLOC(nTnodes * sizeof(yaffs_Tnode));
 682
 683     if (!newTnodes)
 684     {
 685                 T(YAFFS_TRACE_ERROR,(TSTR("yaffs: Could not allocate Tnodes"TENDSTR)));
 686                 return YAFFS_FAIL;
 687     }
 688
 689     // Hook them into the free list
 690     for(i = 0; i < nTnodes - 1; i++)
 691     {
 692         newTnodes[i].internal[0] = &newTnodes[i+1];
 693 #ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
 694         newTnodes[i].internal[YAFFS_NTNODES_INTERNAL] = 1;
 695 #endif
 696     }
 697
 698         newTnodes[nTnodes - 1].internal[0] = dev->freeTnodes;
 699 #ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
 700         newTnodes[nTnodes - 1].internal[YAFFS_NTNODES_INTERNAL] = 1;
 701 #endif
 702         dev->freeTnodes = newTnodes;
 703         dev->nFreeTnodes+= nTnodes;
 704         dev->nTnodesCreated += nTnodes;
 705
 706         // Now add this bunch of tnodes to a list for freeing up.
 707         // NB If we can't add this to the management list it isn't fatal
 708         // but it just means we can't free this bunch of tnodes later.
 709         tnl = YMALLOC(sizeof(yaffs_TnodeList));
 710         if(!tnl)
 711         {
 712                 T(YAFFS_TRACE_ERROR,(TSTR("yaffs: Could not add tnodes to management list" TENDSTR)));
 713
 714         }
 715         else
 716         {
 717                 tnl->tnodes = newTnodes;
 718                 tnl->next = dev->allocatedTnodeList;
 719                 dev->allocatedTnodeList = tnl;
 720         }
 721
 722
 723         T(YAFFS_TRACE_ALLOCATE,(TSTR("yaffs: Tnodes added" TENDSTR)));
 724
 725
 726         return YAFFS_OK;
 727 }
 728
 729
 730 // GetTnode gets us a clean tnode. Tries to make allocate more if we run out
 731 static yaffs_Tnode *yaffs_GetTnode(yaffs_Device *dev)
 732 {
 733         yaffs_Tnode *tn = NULL;
 734
 735         // If there are none left make more
 736         if(!dev->freeTnodes)
 737         {
 738                 yaffs_CreateTnodes(dev,YAFFS_ALLOCATION_NTNODES);
 739         }
 740
 741         if(dev->freeTnodes)
 742         {
 743                 tn = dev->freeTnodes;
 744 #ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
 745         if(tn->internal[YAFFS_NTNODES_INTERNAL] != 1)
 746                 {
 747                         // Hoosterman, this thing looks like it isn't in the list
 748                                 T(YAFFS_TRACE_ALWAYS,(TSTR("yaffs: Tnode list bug 1" TENDSTR)));
 749                 }
 750 #endif
 751                 dev->freeTnodes = dev->freeTnodes->internal[0];
 752                 dev->nFreeTnodes--;
 753                 // zero out
 754                 memset(tn,0,sizeof(yaffs_Tnode));
 755         }
 756
 757
 758         return tn;
 759 }
 760
 761
 762 // FreeTnode frees up a tnode and puts it back on the free list
 763 static void yaffs_FreeTnode(yaffs_Device*dev, yaffs_Tnode *tn)
 764 {
 765         if(tn)
 766         {
 767 #ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
 768         if(tn->internal[YAFFS_NTNODES_INTERNAL] != 0)
 769                 {
 770                         // Hoosterman, this thing looks like it is already in the list
 771                                 T(YAFFS_TRACE_ALWAYS,(TSTR("yaffs: Tnode list bug 2" TENDSTR)));
 772                 }
 773                 tn->internal[YAFFS_NTNODES_INTERNAL] = 1;
 774 #endif
 775                 tn->internal[0] = dev->freeTnodes;
 776                 dev->freeTnodes = tn;
 777                 dev->nFreeTnodes++;
 778         }
 779 }
 780
 781
 782 static void yaffs_DeinitialiseTnodes(yaffs_Device*dev)
 783 {
 784         // Free the list of allocated tnodes
 785         yaffs_TnodeList *tmp;
 786
 787         while(dev->allocatedTnodeList)
 788         {
 789                 tmp =  dev->allocatedTnodeList->next;
 790
 791                 YFREE(dev->allocatedTnodeList->tnodes);
 792                 YFREE(dev->allocatedTnodeList);
 793                 dev->allocatedTnodeList = tmp;
 794
 795         }
 796
 797         dev->freeTnodes = NULL;
 798         dev->nFreeTnodes = 0;
 799 }
 800
 801 static void yaffs_InitialiseTnodes(yaffs_Device*dev)
 802 {
 803         dev->allocatedTnodeList = NULL;
 804         dev->freeTnodes = NULL;
 805         dev->nFreeTnodes = 0;
 806         dev->nTnodesCreated = 0;
 807
 808 }
 809
 810 #if 0
 811 void yaffs_TnodeTest(yaffs_Device *dev)
 812 {
 813
 814         int i;
 815         int j;
 816         yaffs_Tnode *tn[1000];
 817
 818         YINFO("Testing TNodes");
 819
 820         for(j = 0; j < 50; j++)
 821         {
 822                 for(i = 0; i < 1000; i++)
 823                 {
 824                         tn[i] = yaffs_GetTnode(dev);
 825                         if(!tn[i])
 826                         {
 827                                 YALERT("Getting tnode failed");
 828                         }
 829                 }
 830                 for(i = 0; i < 1000; i+=3)
 831                 {
 832                         yaffs_FreeTnode(dev,tn[i]);
 833                         tn[i] = NULL;
 834                 }
 835
 836         }
 837 }
 838 #endif
 839
 840
 841 ////////////////// END OF TNODE MANIPULATION ///////////////////////////
 842
 843 /////////////// Functions to manipulate the look-up tree (made up of tnodes)
 844 // The look up tree is represented by the top tnode and the number of topLevel
 845 // in the tree. 0 means only the level 0 tnode is in the tree.
 846
 847
 848 // FindLevel0Tnode finds the level 0 tnode, if one exists.
 849 // Used when reading.....
 850 static yaffs_Tnode *yaffs_FindLevel0Tnode(yaffs_Device *dev,yaffs_FileStructure *fStruct, __u32 chunkId)
 851 {
 852
 853         yaffs_Tnode *tn = fStruct->top;
 854         __u32 i;
 855         int requiredTallness;
 856         int level = fStruct->topLevel;
 857
 858         // Check sane level and chunk Id
 859         if(level < 0 || level > YAFFS_TNODES_MAX_LEVEL)
 860         {
 861 //              char str[50];
 862 //              sprintf(str,"Bad level %d",level);
 863 //              YALERT(str);
 864                 return NULL;
 865         }
 866
 867         if(chunkId > YAFFS_MAX_CHUNK_ID)
 868         {
 869 //              char str[50];
 870 //              sprintf(str,"Bad chunkId %d",chunkId);
 871 //              YALERT(str);
 872                 return NULL;
 873         }
 874
 875         // First check we're tall enough (ie enough topLevel)
 876
 877         i = chunkId >> (/*dev->chunkGroupBits  + */YAFFS_TNODES_LEVEL0_BITS);
 878         requiredTallness = 0;
 879         while(i)
 880         {
 881                 i >>= YAFFS_TNODES_INTERNAL_BITS;
 882                 requiredTallness++;
 883         }
 884
 885
 886         if(requiredTallness > fStruct->topLevel)
 887         {
 888                 // Not tall enough, so we can't find it, return NULL.
 889                 return NULL;
 890         }
 891
 892
 893         // Traverse down to level 0
 894         while (level > 0 && tn)
 895         {
 896             tn = tn->internal[(chunkId >>(/* dev->chunkGroupBits + */ YAFFS_TNODES_LEVEL0_BITS + (level-1) * YAFFS_TNODES_INTERNAL_BITS)) &
 897                                YAFFS_TNODES_INTERNAL_MASK];
 898                 level--;
 899
 900         }
 901
 902         return tn;
 903 }
 904
 905 // AddOrFindLevel0Tnode finds the level 0 tnode if it exists, otherwise first expands the tree.
 906 // This happens in two steps:
 907 //  1. If the tree isn't tall enough, then make it taller.
 908 //  2. Scan down the tree towards the level 0 tnode adding tnodes if required.
 909 //
 910 // Used when modifying the tree.
 911 //
 912 static yaffs_Tnode *yaffs_AddOrFindLevel0Tnode(yaffs_Device *dev, yaffs_FileStructure *fStruct, __u32 chunkId)
 913 {
 914
 915         yaffs_Tnode *tn;
 916
 917         int requiredTallness;
 918         int i;
 919         int l;
 920
 921         __u32 x;
 922
 923
 924         //T((TSTR("AddOrFind topLevel=%d, chunk=%d"),fStruct->topLevel,chunkId));
 925
 926         // Check sane level and page Id
 927         if(fStruct->topLevel < 0 || fStruct->topLevel > YAFFS_TNODES_MAX_LEVEL)
 928         {
 929 //              char str[50];
 930 //              sprintf(str,"Bad level %d",fStruct->topLevel);
 931 //              YALERT(str);
 932                 return NULL;
 933         }
 934
 935         if(chunkId > YAFFS_MAX_CHUNK_ID)
 936         {
 937 //              char str[50];
 938 //              sprintf(str,"Bad chunkId %d",chunkId);
 939 //              YALERT(str);
 940                 return NULL;
 941         }
 942
 943         // First check we're tall enough (ie enough topLevel)
 944
 945         x = chunkId >> (/*dev->chunkGroupBits + */YAFFS_TNODES_LEVEL0_BITS);
 946         requiredTallness = 0;
 947         while(x)
 948         {
 949                 x >>= YAFFS_TNODES_INTERNAL_BITS;
 950                 requiredTallness++;
 951         }
 952
 953         //T((TSTR(" required=%d"),requiredTallness));
 954
 955
 956         if(requiredTallness > fStruct->topLevel)
 957         {
 958                 // Not tall enough,gotta make the tree taller
 959                 for(i = fStruct->topLevel; i < requiredTallness; i++)
 960                 {
 961                         //T((TSTR(" add new top")));
 962
 963                         tn = yaffs_GetTnode(dev);
 964
 965                         if(tn)
 966                         {
 967                                 tn->internal[0] = fStruct->top;
 968                                 fStruct->top = tn;
 969                         }
 970                         else
 971                         {
 972                                         T(YAFFS_TRACE_ERROR,(TSTR("yaffs: no more tnodes" TENDSTR)));
 973                         }
 974                 }
 975
 976                 fStruct->topLevel = requiredTallness;
 977         }
 978
 979
 980         // Traverse down to level 0, adding anything we need
 981
 982         l = fStruct->topLevel;
 983         tn = fStruct->top;
 984         while (l > 0 && tn)
 985         {
 986                 x = (chunkId >> (/*dev->chunkGroupBits + */YAFFS_TNODES_LEVEL0_BITS + (l-1) * YAFFS_TNODES_INTERNAL_BITS)) &
 987                                YAFFS_TNODES_INTERNAL_MASK;
 988
 989                 //T((TSTR(" [%d:%d]"),l,i));
 990
 991             if(!tn->internal[x])
 992             {
 993                 //T((TSTR(" added")));
 994
 995                 tn->internal[x] = yaffs_GetTnode(dev);
 996             }
 997
 998             tn =        tn->internal[x];
 999                 l--;
1000
1001         }
1002
1003         //TSTR(TENDSTR)));
1004
1005         return tn;
1006 }
1007
1008 // DeleteWorker scans backwards through the tnode tree and deletes all the
1009 // chunks and tnodes in the file
1010 // Returns 1 if the tree was deleted. Returns 0 if it stopped early due to hitting the limit and the delete is incomplete.
1011
1012 static int yaffs_DeleteWorker(yaffs_Object *in, yaffs_Tnode *tn, __u32 level, int chunkOffset,int *limit)
1013 {
1014         int i;
1015         int chunkInInode;
1016         int theChunk;
1017         yaffs_Tags tags;
1018         int found;
1019         int chunkDeleted;
1020         int allDone = 1;
1021
1022
1023         if(tn)
1024         {
1025                 if(level > 0)
1026                 {
1027
1028                         for(i = YAFFS_NTNODES_INTERNAL -1; allDone && i >= 0; i--)
1029                         {
1030                             if(tn->internal[i])
1031                         {
1032                                         if(limit && (*limit) < 0)
1033                                         {
1034                                                 allDone = 0;
1035                                         }
1036                                         else
1037                                         {
1038                                                 allDone = yaffs_DeleteWorker(in,tn->internal[i],level - 1,
1039                                                                                 (chunkOffset << YAFFS_TNODES_INTERNAL_BITS ) + i ,limit);
1040                                         }
1041                                         if(allDone)
1042                                         {
1043                                                 yaffs_FreeTnode(in->myDev,tn->internal[i]);
1044                                         tn->internal[i] = NULL;
1045                                         }
1046                             }
1047
1048                         }
1049                         return (allDone) ? 1 : 0;
1050                 }
1051                 else if(level == 0)
1052                 {
1053                         int hitLimit = 0;
1054
1055                         for(i = YAFFS_NTNODES_LEVEL0 -1; i >= 0 && !hitLimit; i--)
1056                         {
1057                             if(tn->level0[i])
1058                         {
1059                                         int j;
1060
1061                                         chunkInInode = (chunkOffset << YAFFS_TNODES_LEVEL0_BITS ) + i;
1062
1063                                         theChunk =  tn->level0[i] << in->myDev->chunkGroupBits;
1064
1065                                         // Now we need to search for it
1066                                         for(j = 0,found = 0; theChunk && j < in->myDev->chunkGroupSize && !found; j++)
1067                                         {
1068                                                 yaffs_ReadChunkTagsFromNAND(in->myDev,theChunk,&tags,&chunkDeleted);
1069                                                 if(yaffs_TagsMatch(&tags,in->objectId,chunkInInode,chunkDeleted))
1070                                                 {
1071                                                         // found it;
1072                                                         found = 1;
1073
1074                                                 }
1075                                                 else
1076                                                 {
1077                                                         theChunk++;
1078                                                 }
1079                                         }
1080
1081                                         if(found)
1082                                         {
1083                                                 yaffs_DeleteChunk(in->myDev,theChunk,1);
1084                                                 in->nDataChunks--;
1085                                                 if(limit)
1086                                                 {
1087                                                         *limit = *limit-1;
1088                                                         if(*limit <= 0)
1089                                                         {
1090                                                                 hitLimit = 1;
1091                                                         }
1092                                                 }
1093
1094                                         }
1095
1096                                 tn->level0[i] = 0;
1097                             }
1098
1099                         }
1100                         return (i < 0) ? 1 : 0;
1101
1102
1103                 }
1104
1105         }
1106
1107         return 1;
1108
1109 }
1110
1111 // SoftDeleteWorker scans backwards through the tnode tree and soft deletes all the chunks in the file.
1112 // All soft deleting does is increment the block's softdelete count and pulls the chunk out
1113 // of the tnode.
1114 // THus, essentially this is the same as DeleteWorker except that the chunks are soft deleted.
1115 //
1116 static int yaffs_SoftDeleteWorker(yaffs_Object *in, yaffs_Tnode *tn, __u32 level, int chunkOffset)
1117 {
1118         int i;
1119         int chunkInInode;
1120         int theChunk;
1121         yaffs_BlockInfo *theBlock;
1122         yaffs_Tags tags;
1123         int found;
1124         int chunkDeleted;
1125         int allDone = 1;
1126
1127
1128         if(tn)
1129         {
1130                 if(level > 0)
1131                 {
1132
1133                         for(i = YAFFS_NTNODES_INTERNAL -1; allDone && i >= 0; i--)
1134                         {
1135                             if(tn->internal[i])
1136                         {
1137                                                 allDone = yaffs_SoftDeleteWorker(in,tn->internal[i],level - 1,
1138                                                                                 (chunkOffset << YAFFS_TNODES_INTERNAL_BITS ) + i);
1139                                         if(allDone)
1140                                         {
1141                                                 yaffs_FreeTnode(in->myDev,tn->internal[i]);
1142                                         tn->internal[i] = NULL;
1143                                         }
1144                                         else
1145                                         {
1146                                                 //Hoosterman... how could this happen.
1147                                         }
1148                                 }
1149                         }
1150                         return (allDone) ? 1 : 0;
1151                 }
1152                 else if(level == 0)
1153                 {
1154
1155                         for(i = YAFFS_NTNODES_LEVEL0 -1; i >=0; i--)
1156                         {
1157                             if(tn->level0[i])
1158                         {
1159                                         // Note this does not find the real chunk, only the chunk group.
1160                                         // We make an assumption that a chunk group is niot larger than a block.
1161                                         theChunk =  (tn->level0[i] << in->myDev->chunkGroupBits);
1162                                         T(YAFFS_TRACE_SCAN,(TSTR("soft delete tch %d cgb %d chunk %d" TENDSTR),
1163                                                 tn->level0[i],in->myDev->chunkGroupBits,theChunk));
1164
1165                                         theBlock =      yaffs_GetBlockInfo(in->myDev,  theChunk/in->myDev->nChunksPerBlock);
1166                                         if(theBlock)
1167                                         {
1168                                                 theBlock->softDeletions++;
1169                                         }
1170                                 tn->level0[i] = 0;
1171                             }
1172
1173                         }
1174                         return 1;
1175
1176                 }
1177
1178         }
1179
1180         return 1;
1181
1182 }
1183
1184
1185
1186 static void yaffs_SoftDeleteFile(yaffs_Object *obj)
1187 {
1188         if(obj->deleted &&
1189            obj->variantType == YAFFS_OBJECT_TYPE_FILE &&
1190            !obj->softDeleted)
1191         {
1192                 if(obj->nDataChunks <= 0)
1193                 {
1194                                 // Empty file, just delete it immediately
1195                                 yaffs_FreeTnode(obj->myDev,obj->variant.fileVariant.top);
1196                                 obj->variant.fileVariant.top = NULL;
1197                                 T(YAFFS_TRACE_TRACING,(TSTR("yaffs: Deleting empty file %d" TENDSTR),obj->objectId));
1198                                 yaffs_DoGenericObjectDeletion(obj);
1199                 }
1200                 else
1201                 {
1202                         yaffs_SoftDeleteWorker(obj, obj->variant.fileVariant.top, obj->variant.fileVariant.topLevel, 0);
1203                         obj->softDeleted = 1;
1204                 }
1205         }
1206 }
1207
1208
1209
1210
1211
1212 // Pruning removes any part of the file structure tree that is beyond the
1213 // bounds of the file (ie that does not point to chunks).
1214 //
1215 // A file should only get pruned when its size is reduced.
1216 //
1217 // Before pruning, the chunks must be pulled from the tree and the
1218 // level 0 tnode entries must be zeroed out.
1219 // Could also use this for file deletion, but that's probably better handled
1220 // by a special case.
1221
1222 // yaffs_PruneWorker should only be called by yaffs_PruneFileStructure()
1223
1224 static yaffs_Tnode *yaffs_PruneWorker(yaffs_Device *dev, yaffs_Tnode *tn, __u32 level, int del0)
1225 {
1226         int i;
1227         int hasData;
1228
1229         if(tn)
1230         {
1231                 hasData = 0;
1232
1233                 for(i = 0; i < YAFFS_NTNODES_INTERNAL; i++)
1234                 {
1235                     if(tn->internal[i] && level > 0)
1236                     {
1237                         tn->internal[i] = yaffs_PruneWorker(dev,tn->internal[i],level - 1, ( i == 0) ? del0 : 1);
1238                     }
1239
1240                     if(tn->internal[i])
1241                     {
1242                         hasData++;
1243                         }
1244                 }
1245
1246                 if(hasData == 0 && del0)
1247                 {
1248                         // Free and return NULL
1249
1250                         yaffs_FreeTnode(dev,tn);
1251                         tn = NULL;
1252                 }
1253
1254         }
1255
1256         return tn;
1257
1258 }
1259
1260 static int yaffs_PruneFileStructure(yaffs_Device *dev, yaffs_FileStructure *fStruct)
1261 {
1262         int i;
1263         int hasData;
1264         int done = 0;
1265         yaffs_Tnode *tn;
1266
1267         if(fStruct->topLevel > 0)
1268         {
1269                 fStruct->top = yaffs_PruneWorker(dev,fStruct->top, fStruct->topLevel,0);
1270
1271                 // Now we have a tree with all the non-zero branches NULL but the height
1272                 // is the same as it was.
1273                 // Let's see if we can trim internal tnodes to shorten the tree.
1274                 // We can do this if only the 0th element in the tnode is in use
1275                 // (ie all the non-zero are NULL)
1276
1277                 while(fStruct->topLevel && !done)
1278                 {
1279                         tn = fStruct->top;
1280
1281                         hasData = 0;
1282                         for(i = 1; i <YAFFS_NTNODES_INTERNAL; i++)
1283                         {
1284                                 if(tn->internal[i])
1285                         {
1286                                 hasData++;
1287                                 }
1288                         }
1289
1290                         if(!hasData)
1291                         {
1292                                 fStruct->top = tn->internal[0];
1293                                 fStruct->topLevel--;
1294                                 yaffs_FreeTnode(dev,tn);
1295                         }
1296                         else
1297                         {
1298                                 done = 1;
1299                         }
1300                 }
1301         }
1302
1303         return YAFFS_OK;
1304 }
1305
1306
1307
1308
1309
1310 /////////////////////// End of File Structure functions. /////////////////
1311
1312 // yaffs_CreateFreeObjects creates a bunch more objects and
1313 // adds them to the object free list.
1314 static int yaffs_CreateFreeObjects(yaffs_Device *dev, int nObjects)
1315 {
1316     int i;
1317     yaffs_Object *newObjects;
1318     yaffs_ObjectList *list;
1319
1320     if(nObjects < 1) return YAFFS_OK;
1321
1322         // make these things
1323
1324     newObjects = YMALLOC(nObjects * sizeof(yaffs_Object));
1325
1326     if (!newObjects)
1327     {
1328                 T(YAFFS_TRACE_ALLOCATE,(TSTR("yaffs: Could not allocate more objects" TENDSTR)));
1329                 return YAFFS_FAIL;
1330     }
1331
1332     // Hook them into the free list
1333     for(i = 0; i < nObjects - 1; i++)
1334     {
1335         newObjects[i].siblings.next = (struct list_head *)(&newObjects[i+1]);
1336     }
1337
1338         newObjects[nObjects - 1].siblings.next = (void *)dev->freeObjects;
1339         dev->freeObjects = newObjects;
1340         dev->nFreeObjects+= nObjects;
1341         dev->nObjectsCreated+= nObjects;
1342
1343         // Now add this bunch of Objects to a list for freeing up.
1344
1345         list = YMALLOC(sizeof(yaffs_ObjectList));
1346         if(!list)
1347         {
1348                 T(YAFFS_TRACE_ALLOCATE,(TSTR("Could not add objects to management list" TENDSTR)));
1349         }
1350         else
1351         {
1352                 list->objects = newObjects;
1353                 list->next = dev->allocatedObjectList;
1354                 dev->allocatedObjectList = list;
1355         }
1356
1357
1358
1359         return YAFFS_OK;
1360 }
1361
1362
1363 // AllocateEmptyObject gets us a clean Object. Tries to make allocate more if we run out
1364 static yaffs_Object *yaffs_AllocateEmptyObject(yaffs_Device *dev)
1365 {
1366         yaffs_Object *tn = NULL;
1367
1368         // If there are none left make more
1369         if(!dev->freeObjects)
1370         {
1371                 yaffs_CreateFreeObjects(dev,YAFFS_ALLOCATION_NOBJECTS);
1372         }
1373
1374         if(dev->freeObjects)
1375         {
1376                 tn = dev->freeObjects;
1377                 dev->freeObjects = (yaffs_Object *)(dev->freeObjects->siblings.next);
1378                 dev->nFreeObjects--;
1379
1380                 // Now sweeten it up...
1381
1382                 memset(tn,0,sizeof(yaffs_Object));
1383                 tn->myDev = dev;
1384                 tn->chunkId = -1;
1385                 tn->variantType = YAFFS_OBJECT_TYPE_UNKNOWN;
1386                 INIT_LIST_HEAD(&(tn->hardLinks));
1387                 INIT_LIST_HEAD(&(tn->hashLink));
1388                 INIT_LIST_HEAD(&tn->siblings);
1389
1390                 // Add it to the lost and found directory.
1391                 // NB Can't put root or lostNFound in lostNFound so
1392                 // check if lostNFound exists first
1393                 if(dev->lostNFoundDir)
1394                 {
1395                         yaffs_AddObjectToDirectory(dev->lostNFoundDir,tn);
1396                 }
1397         }
1398
1399
1400         return tn;
1401 }
1402
1403 static yaffs_Object *yaffs_CreateFakeDirectory(yaffs_Device *dev,int number,__u32 mode)
1404 {
1405
1406         yaffs_Object *obj = yaffs_CreateNewObject(dev,number,YAFFS_OBJECT_TYPE_DIRECTORY);
1407         if(obj)
1408         {
1409                 obj->fake = 1;                  // it is fake so it has no NAND presence...
1410                 obj->renameAllowed= 0;  // ... and we're not allowed to rename it...
1411                 obj->unlinkAllowed= 0;  // ... or unlink it
1412                 obj->deleted = 0;
1413                 obj->unlinked = 0;
1414                 obj->st_mode = mode;
1415                 obj->myDev = dev;
1416                 obj->chunkId = 0; // Not a valid chunk.
1417         }
1418
1419         return obj;
1420
1421 }
1422
1423
1424 static void yaffs_UnhashObject(yaffs_Object *tn)
1425 {
1426         int bucket;
1427         yaffs_Device *dev = tn->myDev;
1428
1429
1430         // If it is still linked into the bucket list, free from the list
1431         if(!list_empty(&tn->hashLink))
1432         {
1433                 list_del_init(&tn->hashLink);
1434                 bucket =  yaffs_HashFunction(tn->objectId);
1435                 dev->objectBucket[bucket].count--;
1436         }
1437
1438 }
1439
1440
1441 // FreeObject frees up a Object and puts it back on the free list
1442 static void yaffs_FreeObject(yaffs_Object *tn)
1443 {
1444
1445         yaffs_Device *dev = tn->myDev;
1446
1447         yaffs_UnhashObject(tn);
1448
1449         // Link into the free list.
1450         tn->siblings.next = (struct list_head *)(dev->freeObjects);
1451         dev->freeObjects = tn;
1452         dev->nFreeObjects++;
1453 }
1454
1455
1456
1457
1458 static void yaffs_DeinitialiseObjects(yaffs_Device *dev)
1459 {
1460         // Free the list of allocated Objects
1461
1462         yaffs_ObjectList *tmp;
1463
1464         while( dev->allocatedObjectList)
1465         {
1466                 tmp =  dev->allocatedObjectList->next;
1467                 YFREE(dev->allocatedObjectList->objects);
1468                 YFREE(dev->allocatedObjectList);
1469
1470                 dev->allocatedObjectList =  tmp;
1471         }
1472
1473         dev->freeObjects = NULL;
1474         dev->nFreeObjects = 0;
1475 }
1476
1477 static void yaffs_InitialiseObjects(yaffs_Device *dev)
1478 {
1479         int i;
1480
1481         dev->allocatedObjectList = NULL;
1482         dev->freeObjects = NULL;
1483         dev->nFreeObjects = 0;
1484
1485         for(i = 0; i < YAFFS_NOBJECT_BUCKETS; i++)
1486         {
1487                 INIT_LIST_HEAD(&dev->objectBucket[i].list);
1488                 dev->objectBucket[i].count = 0;
1489         }
1490
1491 }
1492
1493
1494
1495
1496
1497
1498 int yaffs_FindNiceObjectBucket(yaffs_Device *dev)
1499 {
1500         static int x = 0;
1501         int i;
1502         int l = 999;
1503         int lowest = 999999;
1504
1505
1506         // First let's see if we can find one that's empty.
1507
1508         for(i = 0; i < 10 && lowest > 0; i++)
1509          {
1510                 x++;
1511                 x %=  YAFFS_NOBJECT_BUCKETS;
1512                 if(dev->objectBucket[x].count < lowest)
1513                 {
1514                         lowest = dev->objectBucket[x].count;
1515                         l = x;
1516                 }
1517
1518         }
1519
1520         // If we didn't find an empty list, then try
1521         // looking a bit further for a short one
1522
1523         for(i = 0; i < 10 && lowest > 3; i++)
1524          {
1525                 x++;
1526                 x %=  YAFFS_NOBJECT_BUCKETS;
1527                 if(dev->objectBucket[x].count < lowest)
1528                 {
1529                         lowest = dev->objectBucket[x].count;
1530                         l = x;
1531                 }
1532
1533         }
1534
1535         return l;
1536 }
1537
1538 static int yaffs_CreateNewObjectNumber(yaffs_Device *dev)
1539 {
1540         int bucket = yaffs_FindNiceObjectBucket(dev);
1541
1542         // Now find an object value that has not already been taken
1543         // by scanning the list.
1544
1545         int found = 0;
1546         struct list_head *i;
1547
1548         __u32 n = (__u32)bucket;
1549
1550         //yaffs_CheckObjectHashSanity();
1551
1552         while(!found)
1553         {
1554                 found = 1;
1555                 n +=  YAFFS_NOBJECT_BUCKETS;
1556                 if(1 ||dev->objectBucket[bucket].count > 0)
1557                 {
1558                         list_for_each(i,&dev->objectBucket[bucket].list)
1559                         {
1560                                 // If there is already one in the list
1561                                 if(i && list_entry(i, yaffs_Object,hashLink)->objectId == n)
1562                                 {
1563                                         found = 0;
1564                                 }
1565                         }
1566                 }
1567         }
1568
1569         //T(("bucket %d count %d inode %d\n",bucket,yaffs_objectBucket[bucket].count,n);
1570
1571         return n;
1572 }
1573
1574 void yaffs_HashObject(yaffs_Object *in)
1575 {
1576         int bucket = yaffs_HashFunction(in->objectId);
1577         yaffs_Device *dev = in->myDev;
1578
1579         if(!list_empty(&in->hashLink))
1580         {
1581                 //YINFO("!!!");
1582         }
1583
1584
1585         list_add(&in->hashLink,&dev->objectBucket[bucket].list);
1586         dev->objectBucket[bucket].count++;
1587
1588 }
1589
1590 yaffs_Object *yaffs_FindObjectByNumber(yaffs_Device *dev,__u32 number)
1591 {
1592         int bucket = yaffs_HashFunction(number);
1593         struct list_head *i;
1594         yaffs_Object *in;
1595
1596         list_for_each(i,&dev->objectBucket[bucket].list)
1597         {
1598                 // Look if it is in the list
1599                 if(i)
1600                 {
1601                         in = list_entry(i, yaffs_Object,hashLink);
1602                         if(in->objectId == number)
1603                         {
1604                                 return in;
1605                         }
1606                 }
1607         }
1608
1609         return NULL;
1610 }
1611
1612
1613
1614 yaffs_Object *yaffs_CreateNewObject(yaffs_Device *dev,int number,yaffs_ObjectType type)
1615 {
1616
1617         yaffs_Object *theObject;
1618
1619         if(number < 0)
1620         {
1621                 number = yaffs_CreateNewObjectNumber(dev);
1622         }
1623
1624         theObject = yaffs_AllocateEmptyObject(dev);
1625
1626         if(theObject)
1627         {
1628                 theObject->fake = 0;
1629                 theObject->renameAllowed = 1;
1630                 theObject->unlinkAllowed = 1;
1631                 theObject->objectId = number;
1632                 yaffs_HashObject(theObject);
1633                 theObject->variantType = type;
1634 #ifdef CONFIG_YAFFS_WINCE
1635                 yfsd_WinFileTimeNow(theObject->win_atime);
1636                 theObject->win_ctime[0] = theObject->win_mtime[0] = theObject->win_atime[0];
1637                 theObject->win_ctime[1] = theObject->win_mtime[1] = theObject->win_atime[1];
1638
1639 #else
1640
1641                 theObject->st_atime = theObject->st_mtime =     theObject->st_ctime = Y_CURRENT_TIME;
1642
1643 #endif
1644                 switch(type)
1645                 {
1646                         case YAFFS_OBJECT_TYPE_FILE:
1647                                 theObject->variant.fileVariant.fileSize = 0;
1648                                 theObject->variant.fileVariant.scannedFileSize = 0;
1649                                 theObject->variant.fileVariant.topLevel = 0;
1650                                 theObject->variant.fileVariant.top  = yaffs_GetTnode(dev);
1651                                 break;
1652                         case YAFFS_OBJECT_TYPE_DIRECTORY:
1653                                 INIT_LIST_HEAD(&theObject->variant.directoryVariant.children);
1654                                 break;
1655                         case YAFFS_OBJECT_TYPE_SYMLINK:
1656                                 // No action required
1657                                 break;
1658                         case YAFFS_OBJECT_TYPE_HARDLINK:
1659                                 // No action required
1660                                 break;
1661                         case YAFFS_OBJECT_TYPE_SPECIAL:
1662                                 // No action required
1663                                 break;
1664                         case YAFFS_OBJECT_TYPE_UNKNOWN:
1665                                 // todo this should not happen
1666                                 break;
1667                 }
1668         }
1669
1670         return theObject;
1671 }
1672
1673 yaffs_Object *yaffs_FindOrCreateObjectByNumber(yaffs_Device *dev, int number,yaffs_ObjectType type)
1674 {
1675         yaffs_Object *theObject = NULL;
1676
1677         if(number > 0)
1678         {
1679                 theObject = yaffs_FindObjectByNumber(dev,number);
1680         }
1681
1682         if(!theObject)
1683         {
1684                 theObject = yaffs_CreateNewObject(dev,number,type);
1685         }
1686
1687         return theObject;
1688
1689 }
1690
1691 char *yaffs_CloneString(const char *str)
1692 {
1693         char *newStr = NULL;
1694
1695         if(str && *str)
1696         {
1697                 newStr = YMALLOC(strlen(str) + 1);
1698                 strcpy(newStr,str);
1699         }
1700
1701         return newStr;
1702
1703 }
1704
1705 //
1706 // Mknod (create) a new object.
1707 // equivalentObject only has meaning for a hard link;
1708 // aliasString only has meaning for a sumlink.
1709 // rdev only has meaning for devices (a subset of special objects)
1710 yaffs_Object *yaffs_MknodObject( yaffs_ObjectType type,
1711                                                                  yaffs_Object *parent,
1712                                                                  const char *name,
1713                                                                  __u32 mode,
1714                                                                  __u32 uid,
1715                                                                  __u32 gid,
1716                                                                  yaffs_Object *equivalentObject,
1717                                                                  const char *aliasString,
1718                                                                  __u32 rdev)
1719 {
1720         yaffs_Object *in;
1721
1722         yaffs_Device *dev = parent->myDev;
1723
1724         // Check if the entry exists. If it does then fail the call since we don't want a dup.
1725         if(yaffs_FindObjectByName(parent,name))
1726         {
1727                 return NULL;
1728         }
1729
1730         in = yaffs_CreateNewObject(dev,-1,type);
1731
1732         if(in)
1733         {
1734                 in->chunkId = -1;
1735                 in->valid = 1;
1736                 in->variantType = type;
1737
1738                 in->st_mode  = mode;
1739
1740 #ifdef CONFIG_YAFFS_WINCE
1741                 yfsd_WinFileTimeNow(in->win_atime);
1742                 in->win_ctime[0] = in->win_mtime[0] = in->win_atime[0];
1743                 in->win_ctime[1] = in->win_mtime[1] = in->win_atime[1];
1744
1745 #else
1746
1747                 in->st_atime = in->st_mtime = in->st_ctime = Y_CURRENT_TIME;
1748                 in->st_rdev  = rdev;
1749                 in->st_uid   = uid;
1750                 in->st_gid   = gid;
1751 #endif
1752                 in->nDataChunks = 0;
1753
1754                 yaffs_SetObjectName(in,name);
1755                 in->dirty = 1;
1756
1757                 yaffs_AddObjectToDirectory(parent,in);
1758
1759                 in->myDev = parent->myDev;
1760
1761
1762                 switch(type)
1763                 {
1764                         case YAFFS_OBJECT_TYPE_SYMLINK:
1765                                 in->variant.symLinkVariant.alias = yaffs_CloneString(aliasString);
1766                                 break;
1767                         case YAFFS_OBJECT_TYPE_HARDLINK:
1768                                 in->variant.hardLinkVariant.equivalentObject = equivalentObject;
1769                                 in->variant.hardLinkVariant.equivalentObjectId = equivalentObject->objectId;
1770                                 list_add(&in->hardLinks,&equivalentObject->hardLinks);
1771                                 break;
1772                         case YAFFS_OBJECT_TYPE_FILE: // do nothing
1773                         case YAFFS_OBJECT_TYPE_DIRECTORY: // do nothing
1774                         case YAFFS_OBJECT_TYPE_SPECIAL: // do nothing
1775                         case YAFFS_OBJECT_TYPE_UNKNOWN:
1776                                 break;
1777                 }
1778
1779                 if(/*yaffs_GetNumberOfFreeChunks(dev) <= 0 || */
1780                    yaffs_UpdateObjectHeader(in,name,0) < 0)
1781                 {
1782                         // Could not create the object header, fail the creation
1783                         yaffs_AbortHalfCreatedObject(in);
1784                         in = NULL;
1785                 }
1786
1787         }
1788
1789         return in;
1790 }
1791
1792 yaffs_Object *yaffs_MknodFile(yaffs_Object *parent,const char *name, __u32 mode, __u32 uid, __u32 gid)
1793 {
1794         return yaffs_MknodObject(YAFFS_OBJECT_TYPE_FILE,parent,name,mode,uid,gid,NULL,NULL,0);
1795 }
1796
1797 yaffs_Object *yaffs_MknodDirectory(yaffs_Object *parent,const char *name, __u32 mode, __u32 uid, __u32 gid)
1798 {
1799         return yaffs_MknodObject(YAFFS_OBJECT_TYPE_DIRECTORY,parent,name,mode,uid,gid,NULL,NULL,0);
1800 }
1801
1802 yaffs_Object *yaffs_MknodSpecial(yaffs_Object *parent,const char *name, __u32 mode, __u32 uid, __u32 gid, __u32 rdev)
1803 {
1804         return yaffs_MknodObject(YAFFS_OBJECT_TYPE_DIRECTORY,parent,name,mode,uid,gid,NULL,NULL,rdev);
1805 }
1806
1807 yaffs_Object *yaffs_MknodSymLink(yaffs_Object *parent,const char *name, __u32 mode, __u32 uid, __u32 gid,const char *alias)
1808 {
1809         return yaffs_MknodObject(YAFFS_OBJECT_TYPE_SYMLINK,parent,name,mode,uid,gid,NULL,alias,0);
1810 }
1811
1812 // NB yaffs_Link returns the object id of the equivalent object.
1813 yaffs_Object *yaffs_Link(yaffs_Object *parent, const char *name, yaffs_Object *equivalentObject)
1814 {
1815         // Get the real object in case we were fed a hard link as an equivalent object
1816         equivalentObject = yaffs_GetEquivalentObject(equivalentObject);
1817
1818         if(yaffs_MknodObject(YAFFS_OBJECT_TYPE_HARDLINK,parent,name,0,0,0,equivalentObject,NULL,0))
1819         {
1820                 return equivalentObject;
1821         }
1822         else
1823         {
1824                 return NULL;
1825         }
1826
1827 }
1828
1829
1830 static int yaffs_ChangeObjectName(yaffs_Object *obj, yaffs_Object *newDir, const char *newName,int force)
1831 {
1832         int unlinkOp;
1833
1834         if(newDir == NULL)
1835         {
1836                 newDir = obj->parent; // use the old directory
1837         }
1838
1839         unlinkOp = (newDir == obj->myDev->unlinkedDir && obj->variantType == YAFFS_OBJECT_TYPE_FILE);
1840
1841         // If the object is a file going into the unlinked directory, then it is OK to just stuff it in since
1842         // duplicate names are allowed.
1843         // Otherwise only proceed if the new name does not exist and if we're putting it into a directory.
1844         if( (unlinkOp||
1845                  force ||
1846                  !yaffs_FindObjectByName(newDir,newName))  &&
1847              newDir->variantType == YAFFS_OBJECT_TYPE_DIRECTORY)
1848         {
1849                 yaffs_SetObjectName(obj,newName);
1850                 obj->dirty = 1;
1851
1852                 yaffs_AddObjectToDirectory(newDir,obj);
1853
1854                 if(unlinkOp) obj->unlinked = 1;
1855
1856
1857                 if(yaffs_UpdateObjectHeader(obj,newName,0) >= 0)
1858                 {
1859                         return YAFFS_OK;
1860                 }
1861         }
1862
1863         return YAFFS_FAIL;
1864 }
1865
1866
1867
1868 int yaffs_RenameObject(yaffs_Object *oldDir, const char *oldName, yaffs_Object *newDir, const char *newName)
1869 {
1870         yaffs_Object *obj;
1871         int force = 0;
1872
1873 #ifdef CONFIG_YAFFS_CASE_INSENSITIVE
1874         // Special case for WinCE.
1875         // While look-up is case insensitive, the name isn't.
1876         // THerefore we might want to change x.txt to X.txt
1877         if(oldDir == newDir && _stricmp(oldName,newName) == 0)
1878         {
1879                 force = 1;
1880         }
1881 #endif
1882
1883         obj = yaffs_FindObjectByName(oldDir,oldName);
1884         if(obj && obj->renameAllowed)
1885         {
1886                 return yaffs_ChangeObjectName(obj,newDir,newName,force);
1887         }
1888         return YAFFS_FAIL;
1889 }
1890
1891
1892
1893 static int yaffs_CheckObjectHashSanity(yaffs_Device *dev)
1894 {
1895         // Scan the buckets and check that the lists
1896         // have as many members as the count says there are
1897         int bucket;
1898         int countEm;
1899         struct list_head *j;
1900         int ok = YAFFS_OK;
1901
1902         for(bucket = 0; bucket < YAFFS_NOBJECT_BUCKETS; bucket++)
1903         {
1904                 countEm = 0;
1905
1906                 list_for_each(j,&dev->objectBucket[bucket].list)
1907                 {
1908                         countEm++;
1909                 }
1910
1911                 if(countEm != dev->objectBucket[bucket].count)
1912                 {
1913                         T(YAFFS_TRACE_ERROR,(TSTR("Inode hash inconsistency" TENDSTR)));
1914                         ok = YAFFS_FAIL;
1915                 }
1916         }
1917
1918         return ok;
1919 }
1920
1921 #if 0
1922 void yaffs_ObjectTest(yaffs_Device *dev)
1923 {
1924         yaffs_Object *in[1000];
1925         int inNo[1000];
1926         yaffs_Object *inold[1000];
1927         int i;
1928         int j;
1929
1930         memset(in,0,1000*sizeof(yaffs_Object *));
1931         memset(inold,0,1000*sizeof(yaffs_Object *));
1932
1933         yaffs_CheckObjectHashSanity(dev);
1934
1935         for(j = 0; j < 10; j++)
1936         {
1937                 //T(("%d\n",j));
1938
1939                 for(i = 0; i < 1000; i++)
1940                 {
1941                         in[i] = yaffs_CreateNewObject(dev,-1,YAFFS_OBJECT_TYPE_FILE);
1942                         if(!in[i])
1943                         {
1944                                 YINFO("No more inodes");
1945                         }
1946                         else
1947                         {
1948                                 inNo[i] = in[i]->objectId;
1949                         }
1950                 }
1951
1952                 for(i = 0; i < 1000; i++)
1953                 {
1954                         if(yaffs_FindObjectByNumber(dev,inNo[i]) != in[i])
1955                         {
1956                                 //T(("Differnce in look up test\n"));
1957                         }
1958                         else
1959                         {
1960                                 // T(("Look up ok\n"));
1961                         }
1962                 }
1963
1964                 yaffs_CheckObjectHashSanity(dev);
1965
1966                 for(i = 0; i < 1000; i+=3)
1967                 {
1968                         yaffs_FreeObject(in[i]);
1969                         in[i] = NULL;
1970                 }
1971
1972
1973                 yaffs_CheckObjectHashSanity(dev);
1974         }
1975
1976 }
1977
1978 #endif
1979
1980 /////////////////////////// Block Management and Page Allocation ///////////////////
1981
1982
1983 static int yaffs_InitialiseBlocks(yaffs_Device *dev,int nBlocks)
1984 {
1985         dev->allocationBlock = -1; // force it to get a new one
1986         //Todo we're assuming the malloc will pass.
1987         dev->blockInfo = YMALLOC(nBlocks * sizeof(yaffs_BlockInfo));
1988         // Set up dynamic blockinfo stuff.
1989         dev->chunkBitmapStride = (dev->nChunksPerBlock+7)/8;
1990         dev->chunkBits = YMALLOC(dev->chunkBitmapStride * nBlocks);
1991         if(dev->blockInfo && dev->chunkBits)
1992         {
1993                 memset(dev->blockInfo,0,nBlocks * sizeof(yaffs_BlockInfo));
1994                 memset(dev->chunkBits,0,dev->chunkBitmapStride * nBlocks);
1995                 return YAFFS_OK;
1996         }
1997
1998         return YAFFS_FAIL;
1999
2000 }
2001
2002 static void yaffs_DeinitialiseBlocks(yaffs_Device *dev)
2003 {
2004         YFREE(dev->blockInfo);
2005         dev->blockInfo = NULL;
2006         YFREE(dev->chunkBits);
2007         dev->chunkBits = NULL;
2008 }
2009
2010 // FindDiretiestBlock is used to select the dirtiest block (or close enough)
2011 // for garbage collection.
2012
2013 static int yaffs_FindDirtiestBlock(yaffs_Device *dev,int aggressive)
2014 {
2015
2016         int b = dev->currentDirtyChecker;
2017
2018         int i;
2019         int iterations;
2020         int dirtiest = -1;
2021         int pagesInUse;
2022         yaffs_BlockInfo *bi;
2023
2024         // If we're doing aggressive GC then we are happy to take a less-dirty block, and
2025         // search further.
2026
2027         pagesInUse = (aggressive)? dev->nChunksPerBlock : YAFFS_PASSIVE_GC_CHUNKS + 1;
2028         if(aggressive)
2029         {
2030                 iterations = dev->endBlock - dev->startBlock + 1;
2031         }
2032         else
2033         {
2034                 iterations = dev->endBlock - dev->startBlock + 1;
2035                 iterations = iterations / 16;
2036                 if(iterations > 200)
2037                 {
2038                         iterations = 200;
2039                 }
2040         }
2041
2042         for(i = 0; i <= iterations && pagesInUse > 0 ; i++)
2043         {
2044                 b++;
2045                 if ( b < dev->startBlock || b > dev->endBlock)
2046                 {
2047                         b =  dev->startBlock;
2048                 }
2049
2050                 if(b < dev->startBlock || b > dev->endBlock)
2051                 {
2052                         T(YAFFS_TRACE_ERROR,(TSTR("**>> Block %d is not valid" TENDSTR),b));
2053                         YBUG();
2054                 }
2055
2056                 bi = yaffs_GetBlockInfo(dev,b);
2057
2058                 if(bi->blockState == YAFFS_BLOCK_STATE_FULL &&
2059                    (bi->pagesInUse - bi->softDeletions )< pagesInUse)
2060                 {
2061                         dirtiest = b;
2062                         pagesInUse = (bi->pagesInUse - bi->softDeletions);
2063                 }
2064         }
2065
2066         dev->currentDirtyChecker = b;
2067
2068         return dirtiest;
2069 }
2070
2071
2072 static void yaffs_BlockBecameDirty(yaffs_Device *dev,int blockNo)
2073 {
2074         yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev,blockNo);
2075
2076         int erasedOk = 0;
2077
2078         // If the block is still healthy erase it and mark as clean.
2079         // If the block has had a data failure, then retire it.
2080         bi->blockState = YAFFS_BLOCK_STATE_DIRTY;
2081
2082         if(!bi->needsRetiring)
2083         {
2084                 erasedOk = yaffs_EraseBlockInNAND(dev,blockNo);
2085                 if(!erasedOk)
2086                 {
2087                         T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,(TSTR("**>> Erasure failed %d" TENDSTR),blockNo));
2088                 }
2089         }
2090
2091         if( erasedOk )
2092         {
2093                 // Clean it up...
2094                 bi->blockState = YAFFS_BLOCK_STATE_EMPTY;
2095                 dev->nErasedBlocks++;
2096                 bi->pagesInUse = 0;
2097                 bi->softDeletions = 0;
2098                 yaffs_ClearChunkBits(dev,blockNo);
2099
2100                 T(YAFFS_TRACE_ERASE,(TSTR("Erased block %d" TENDSTR),blockNo));
2101         }
2102         else
2103         {
2104                 yaffs_RetireBlock(dev,blockNo);
2105                 T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,(TSTR("**>> Block %d retired" TENDSTR),blockNo));
2106         }
2107 }
2108
2109
2110 static int yaffs_FindBlockForAllocation(yaffs_Device *dev)
2111 {
2112         int i;
2113
2114         yaffs_BlockInfo *bi;
2115
2116         if(dev->nErasedBlocks < 1)
2117         {
2118                 // Hoosterman we've got a problem.
2119                 // Can't get space to gc
2120                 T(YAFFS_TRACE_ERROR, (TSTR("yaffs tragedy: no space during gc" TENDSTR)));
2121
2122                 return -1;
2123         }
2124
2125         // Find an empty block.
2126
2127         for(i = dev->startBlock; i <= dev->endBlock; i++)
2128         {
2129                 dev->allocationBlockFinder++;
2130                 if(dev->allocationBlockFinder <dev->startBlock || dev->allocationBlockFinder> dev->endBlock)
2131                 {
2132                         dev->allocationBlockFinder = dev->startBlock;
2133                 }
2134
2135                 bi = yaffs_GetBlockInfo(dev,dev->allocationBlockFinder);
2136
2137                 if(bi->blockState == YAFFS_BLOCK_STATE_EMPTY)
2138                 {
2139                         bi->blockState = YAFFS_BLOCK_STATE_ALLOCATING;
2140                         dev->nErasedBlocks--;
2141                         return dev->allocationBlockFinder;
2142                 }
2143         }
2144
2145         return -1;
2146 }
2147
2148
2149
2150 static int yaffs_AllocateChunk(yaffs_Device *dev,int useReserve)
2151 {
2152         int retVal;
2153         yaffs_BlockInfo *bi;
2154
2155         if(dev->allocationBlock < 0)
2156         {
2157                 // Get next block to allocate off
2158                 dev->allocationBlock = yaffs_FindBlockForAllocation(dev);
2159                 dev->allocationPage = 0;
2160         }
2161
2162         if(!useReserve &&  dev->nErasedBlocks <= dev->nReservedBlocks)
2163         {
2164                 // Not enough space to allocate unless we're allowed to use the reserve.
2165                 return -1;
2166         }
2167
2168         // Next page please....
2169         if(dev->allocationBlock >= 0)
2170         {
2171                 bi = yaffs_GetBlockInfo(dev,dev->allocationBlock);
2172
2173                 retVal = (dev->allocationBlock * dev->nChunksPerBlock) +
2174                                   dev->allocationPage;
2175                 bi->pagesInUse++;
2176                 yaffs_SetChunkBit(dev,dev->allocationBlock,dev->allocationPage);
2177
2178                 dev->allocationPage++;
2179
2180                 dev->nFreeChunks--;
2181
2182                 // If the block is full set the state to full
2183                 if(dev->allocationPage >= dev->nChunksPerBlock)
2184                 {
2185                         bi->blockState = YAFFS_BLOCK_STATE_FULL;
2186                         dev->allocationBlock = -1;
2187                 }
2188
2189
2190                 return retVal;
2191
2192         }
2193         T(YAFFS_TRACE_ERROR,(TSTR("!!!!!!!!! Allocator out !!!!!!!!!!!!!!!!!" TENDSTR)));
2194
2195         return -1;
2196 }
2197
2198 // To determine if we have enough space we just look at the
2199 // number of erased blocks.
2200 // The cache is allowed to use reserved blocks.
2201
2202 static int yaffs_CheckSpaceForChunkCache(yaffs_Device *dev)
2203 {
2204         return (dev->nErasedBlocks >= dev->nReservedBlocks);
2205 }
2206
2207
2208 static int  yaffs_GarbageCollectBlock(yaffs_Device *dev,int block)
2209 {
2210         int oldChunk;
2211         int newChunk;
2212         int chunkInBlock;
2213         int markNAND;
2214
2215
2216         yaffs_Spare spare;
2217         yaffs_Tags  tags;
2218         __u8  buffer[YAFFS_BYTES_PER_CHUNK];
2219
2220 //      yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev,block);
2221
2222         yaffs_Object *object;
2223
2224         //T(("Collecting block %d n %d bits %x\n",block, bi->pagesInUse, bi->pageBits));
2225
2226         for(chunkInBlock = 0,oldChunk = block * dev->nChunksPerBlock;
2227             chunkInBlock < dev->nChunksPerBlock && yaffs_StillSomeChunkBits(dev,block);
2228             chunkInBlock++, oldChunk++ )
2229         {
2230                 if(yaffs_CheckChunkBit(dev,block,chunkInBlock))
2231                 {
2232
2233                         // This page is in use and might need to be copied off
2234
2235                         markNAND = 1;
2236
2237                         //T(("copying page %x from %d to %d\n",mask,oldChunk,newChunk));
2238
2239                         yaffs_ReadChunkFromNAND(dev,oldChunk,buffer, &spare,1);
2240
2241                         yaffs_GetTagsFromSpare(dev,&spare,&tags);
2242
2243                         object = yaffs_FindObjectByNumber(dev,tags.objectId);
2244
2245                         if(object && object->deleted && tags.chunkId != 0)
2246                         {
2247                                 // Data chunk in a deleted file, throw it away
2248                                 // It's a deleted data chunk,
2249                                 // No need to copy this, just forget about it and fix up the
2250                                 // object.
2251
2252                                 //yaffs_PutChunkIntoFile(object, tags.chunkId, 0,0);
2253                                 object->nDataChunks--;
2254
2255                                 if(object->nDataChunks <= 0)
2256                                 {
2257                                         // Time to delete the file too
2258                                         yaffs_FreeTnode(object->myDev,object->variant.fileVariant.top);
2259                                         object->variant.fileVariant.top = NULL;
2260                                         T(YAFFS_TRACE_TRACING,(TSTR("yaffs: About to finally delete object %d" TENDSTR),object->objectId));
2261                                         yaffs_DoGenericObjectDeletion(object);
2262                                 }
2263                                 markNAND = 0;
2264                         }
2265                         else if( 0 /* Todo object && object->deleted && object->nDataChunks == 0 */)
2266                         {
2267                                 // Deleted object header with no data chunks.
2268                                 // Can be discarded and the file deleted.
2269                                 object->chunkId = 0;
2270                                 yaffs_FreeTnode(object->myDev,object->variant.fileVariant.top);
2271                                 object->variant.fileVariant.top = NULL;
2272                                 yaffs_DoGenericObjectDeletion(object);
2273
2274                         }
2275                         else if(object)
2276                         {
2277                                 // It's either a data chunk in a live file or
2278                                 // an ObjectHeader, so we're interested in it.
2279                                 // NB Need to keep the ObjectHeaders of deleted files
2280                                 // until the whole file has been deleted off
2281                                 tags.serialNumber++;
2282                                 yaffs_LoadTagsIntoSpare(&spare,&tags);
2283
2284                                 dev->nGCCopies++;
2285
2286                                 newChunk = yaffs_WriteNewChunkToNAND(dev, buffer, &spare,1);
2287
2288                                 if(newChunk < 0)
2289                                 {
2290                                         return YAFFS_FAIL;
2291                                 }
2292
2293                                 // Ok, now fix up the Tnodes etc.
2294
2295                                 if(tags.chunkId == 0)
2296                                 {
2297                                         // It's a header
2298                                         object->chunkId = newChunk;
2299                                         object->serial = tags.serialNumber;
2300                                 }
2301                                 else
2302                                 {
2303                                         // It's a data chunk
2304                                         yaffs_PutChunkIntoFile(object, tags.chunkId, newChunk,0);
2305                                 }
2306                         }
2307
2308                         yaffs_DeleteChunk(dev,oldChunk,markNAND);
2309
2310                 }
2311         }
2312
2313         return YAFFS_OK;
2314 }
2315
2316
2317 static yaffs_Object *yaffs_FindDeletedUnlinkedFile(yaffs_Device *dev)
2318 {
2319         // find a file to delete
2320         struct list_head *i;
2321         yaffs_Object *l;
2322
2323
2324         //Scan the unlinked files looking for one to delete
2325         list_for_each(i,&dev->unlinkedDir->variant.directoryVariant.children)
2326         {
2327                 if(i)
2328                 {
2329                         l = list_entry(i, yaffs_Object,siblings);
2330                         if(l->deleted)
2331                         {
2332                                 return l;
2333                         }
2334                 }
2335         }
2336         return NULL;
2337 }
2338
2339
2340 static void yaffs_DoUnlinkedFileDeletion(yaffs_Device *dev)
2341 {
2342         // This does background deletion on unlinked files.. only deleted ones.
2343         // If we don't have a file we're working on then find one
2344         if(!dev->unlinkedDeletion && dev->nDeletedFiles > 0)
2345         {
2346                 dev->unlinkedDeletion = yaffs_FindDeletedUnlinkedFile(dev);
2347         }
2348
2349         // OK, we're working on a file...
2350         if(dev->unlinkedDeletion)
2351         {
2352                 yaffs_Object *obj = dev->unlinkedDeletion;
2353                 int delresult;
2354                 int limit; // Number of chunks to delete in a file.
2355                                    // NB this can be exceeded, but not by much.
2356
2357                 limit = -1;
2358
2359                 delresult = yaffs_DeleteWorker(obj, obj->variant.fileVariant.top, obj->variant.fileVariant.topLevel, 0,&limit);
2360
2361                 if(obj->nDataChunks == 0)
2362                 {
2363                         // Done all the deleting of data chunks.
2364                         // Now dump the header and clean up
2365                         yaffs_FreeTnode(dev,obj->variant.fileVariant.top);
2366                         obj->variant.fileVariant.top = NULL;
2367                         yaffs_DoGenericObjectDeletion(obj);
2368                         dev->nDeletedFiles--;
2369                         dev->nUnlinkedFiles--;
2370                         dev->nBackgroundDeletions++;
2371                         dev->unlinkedDeletion = NULL;
2372                 }
2373         }
2374 }
2375
2376
2377 #if 0
2378 #define YAFFS_GARBAGE_COLLECT_LOW_WATER 2
2379 static int yaffs_CheckGarbageCollection(yaffs_Device *dev)
2380 {
2381         int block;
2382         int aggressive=0;
2383
2384         //yaffs_DoUnlinkedFileDeletion(dev);
2385
2386         if(dev->nErasedBlocks <= (dev->nReservedBlocks + YAFFS_GARBAGE_COLLECT_LOW_WATER))
2387         {
2388                 aggressive = 1;
2389         }
2390
2391         if(aggressive)
2392         {
2393                 block = yaffs_FindDirtiestBlock(dev,aggressive);
2394
2395                 if(block >= 0)
2396                 {
2397                         dev->garbageCollections++;
2398                         return yaffs_GarbageCollectBlock(dev,block);
2399                 }
2400                 else
2401                 {
2402                         return YAFFS_FAIL;
2403                 }
2404         }
2405
2406         return YAFFS_OK;
2407 }
2408 #endif
2409
2410 // New garbage collector
2411 // If we're very low on erased blocks then we do aggressive garbage collection
2412 // otherwise we do "passive" garbage collection.
2413 // Aggressive gc looks further (whole array) and will accept dirtier blocks.
2414 // Passive gc only inspects smaller areas and will only accept cleaner blocks.
2415 //
2416 // The idea is to help clear out space in a more spread-out manner.
2417 // Dunno if it really does anything useful.
2418 //
2419 static int yaffs_CheckGarbageCollection(yaffs_Device *dev)
2420 {
2421         int block;
2422         int aggressive=0;
2423
2424         //yaffs_DoUnlinkedFileDeletion(dev);
2425
2426         if(dev->nErasedBlocks <= (dev->nReservedBlocks + 1))
2427         {
2428                 aggressive = 1;
2429         }
2430
2431         block = yaffs_FindDirtiestBlock(dev,aggressive);
2432
2433         if(block >= 0)
2434         {
2435                 dev->garbageCollections++;
2436                 if(!aggressive)
2437                 {
2438                         dev->passiveGarbageCollections++;
2439                 }
2440
2441                 T(YAFFS_TRACE_GC,(TSTR("yaffs: GC erasedBlocks %d aggressive %d" TENDSTR),dev->nErasedBlocks,aggressive));
2442
2443                 return yaffs_GarbageCollectBlock(dev,block);
2444         }
2445
2446         return aggressive ? YAFFS_FAIL : YAFFS_OK;
2447 }
2448
2449
2450 //////////////////////////// TAGS ///////////////////////////////////////
2451
2452 static void yaffs_LoadTagsIntoSpare(yaffs_Spare *sparePtr, yaffs_Tags *tagsPtr)
2453 {
2454         yaffs_TagsUnion *tu = (yaffs_TagsUnion *)tagsPtr;
2455
2456         yaffs_CalcTagsECC(tagsPtr);
2457
2458         sparePtr->tagByte0 = tu->asBytes[0];
2459         sparePtr->tagByte1 = tu->asBytes[1];
2460         sparePtr->tagByte2 = tu->asBytes[2];
2461         sparePtr->tagByte3 = tu->asBytes[3];
2462         sparePtr->tagByte4 = tu->asBytes[4];
2463         sparePtr->tagByte5 = tu->asBytes[5];
2464         sparePtr->tagByte6 = tu->asBytes[6];
2465         sparePtr->tagByte7 = tu->asBytes[7];
2466 }
2467
2468 static void yaffs_GetTagsFromSpare(yaffs_Device *dev, yaffs_Spare *sparePtr,yaffs_Tags *tagsPtr)
2469 {
2470         yaffs_TagsUnion *tu = (yaffs_TagsUnion *)tagsPtr;
2471         int result;
2472
2473         tu->asBytes[0]= sparePtr->tagByte0;
2474         tu->asBytes[1]= sparePtr->tagByte1;
2475         tu->asBytes[2]= sparePtr->tagByte2;
2476         tu->asBytes[3]= sparePtr->tagByte3;
2477         tu->asBytes[4]= sparePtr->tagByte4;
2478         tu->asBytes[5]= sparePtr->tagByte5;
2479         tu->asBytes[6]= sparePtr->tagByte6;
2480         tu->asBytes[7]= sparePtr->tagByte7;
2481
2482         result =  yaffs_CheckECCOnTags(tagsPtr);
2483         if(result> 0)
2484         {
2485                 dev->tagsEccFixed++;
2486         }
2487         else if(result <0)
2488         {
2489                 dev->tagsEccUnfixed++;
2490         }
2491 }
2492
2493 static void yaffs_SpareInitialise(yaffs_Spare *spare)
2494 {
2495         memset(spare,0xFF,sizeof(yaffs_Spare));
2496 }
2497
2498 static int yaffs_ReadChunkTagsFromNAND(yaffs_Device *dev,int chunkInNAND, yaffs_Tags *tags, int *chunkDeleted)
2499 {
2500         if(tags)
2501         {
2502                 yaffs_Spare spare;
2503                 if(yaffs_ReadChunkFromNAND(dev,chunkInNAND,NULL,&spare,1) == YAFFS_OK)
2504                 {
2505                         *chunkDeleted = (yaffs_CountBits(spare.pageStatus) < 7) ? 1 : 0;
2506                         yaffs_GetTagsFromSpare(dev,&spare,tags);
2507                         return YAFFS_OK;
2508                 }
2509                 else
2510                 {
2511                         return YAFFS_FAIL;
2512                 }
2513         }
2514
2515         return YAFFS_OK;
2516 }
2517
2518 #if 0
2519 static int yaffs_WriteChunkWithTagsToNAND(yaffs_Device *dev,int chunkInNAND, const __u8 *buffer, yaffs_Tags *tags)
2520 {
2521         // NB There must be tags, data is optional
2522         // If there is data, then an ECC is calculated on it.
2523
2524         yaffs_Spare spare;
2525
2526         if(!tags)
2527         {
2528                 return YAFFS_FAIL;
2529         }
2530
2531         yaffs_SpareInitialise(&spare);
2532
2533         if(!dev->useNANDECC && buffer)
2534         {
2535                 yaffs_CalcECC(buffer,&spare);
2536         }
2537
2538         yaffs_LoadTagsIntoSpare(&spare,tags);
2539
2540         return yaffs_WriteChunkToNAND(dev,chunkInNAND,buffer,&spare);
2541
2542 }
2543 #endif
2544
2545
2546 static int yaffs_WriteNewChunkWithTagsToNAND(yaffs_Device *dev, const __u8 *buffer, yaffs_Tags *tags, int useReserve)
2547 {
2548         // NB There must be tags, data is optional
2549         // If there is data, then an ECC is calculated on it.
2550
2551         yaffs_Spare spare;
2552
2553         if(!tags)
2554         {
2555                 return YAFFS_FAIL;
2556         }
2557
2558         yaffs_SpareInitialise(&spare);
2559
2560         if(!dev->useNANDECC && buffer)
2561         {
2562                 yaffs_CalcECC(buffer,&spare);
2563         }
2564
2565         yaffs_LoadTagsIntoSpare(&spare,tags);
2566
2567         return yaffs_WriteNewChunkToNAND(dev,buffer,&spare,useReserve);
2568
2569 }
2570
2571 static int yaffs_TagsMatch(const yaffs_Tags *tags, int objectId, int chunkInObject, int chunkDeleted)
2572 {
2573         return  (  tags->chunkId == chunkInObject &&
2574                            tags->objectId == objectId &&
2575                            !chunkDeleted) ? 1 : 0;
2576
2577 }
2578
2579
2580
2581 int yaffs_FindChunkInFile(yaffs_Object *in,int chunkInInode,yaffs_Tags *tags)
2582 {
2583         //Get the Tnode, then get the level 0 offset chunk offset
2584     yaffs_Tnode *tn;
2585     int theChunk = -1;
2586     yaffs_Tags localTags;
2587     int i;
2588     int found = 0;
2589     int chunkDeleted;
2590
2591     yaffs_Device *dev = in->myDev;
2592
2593
2594     if(!tags)
2595     {
2596         // Passed a NULL, so use our own tags space
2597         tags = &localTags;
2598     }
2599
2600     tn = yaffs_FindLevel0Tnode(dev,&in->variant.fileVariant, chunkInInode);
2601
2602     if(tn)
2603     {
2604                 theChunk = tn->level0[chunkInInode & YAFFS_TNODES_LEVEL0_MASK] << dev->chunkGroupBits;
2605
2606                 // Now we need to do the shifting etc and search for it
2607                 for(i = 0,found = 0; theChunk && i < dev->chunkGroupSize && !found; i++)
2608                 {
2609                         yaffs_ReadChunkTagsFromNAND(dev,theChunk,tags,&chunkDeleted);
2610                         if(yaffs_TagsMatch(tags,in->objectId,chunkInInode,chunkDeleted))
2611                         {
2612                                 // found it;
2613                                 found = 1;
2614                         }
2615                         else
2616                         {
2617                                 theChunk++;
2618                         }
2619                 }
2620     }
2621     return found ? theChunk : -1;
2622 }
2623
2624 int yaffs_FindAndDeleteChunkInFile(yaffs_Object *in,int chunkInInode,yaffs_Tags *tags)
2625 {
2626         //Get the Tnode, then get the level 0 offset chunk offset
2627     yaffs_Tnode *tn;
2628     int theChunk = -1;
2629     yaffs_Tags localTags;
2630     int i;
2631     int found = 0;
2632     yaffs_Device *dev = in->myDev;
2633     int chunkDeleted;
2634
2635     if(!tags)
2636     {
2637         // Passed a NULL, so use our own tags space
2638         tags = &localTags;
2639     }
2640
2641     tn = yaffs_FindLevel0Tnode(dev,&in->variant.fileVariant, chunkInInode);
2642
2643     if(tn)
2644     {
2645
2646                 theChunk = tn->level0[chunkInInode & YAFFS_TNODES_LEVEL0_MASK] << dev->chunkGroupBits;
2647
2648                 // Now we need to do the shifting etc and search for it
2649                 for(i = 0,found = 0; theChunk && i < dev->chunkGroupSize && !found; i++)
2650                 {
2651                         yaffs_ReadChunkTagsFromNAND(dev,theChunk,tags,&chunkDeleted);
2652                         if(yaffs_TagsMatch(tags,in->objectId,chunkInInode,chunkDeleted))
2653                         {
2654                                 // found it;
2655                                 found = 1;
2656                         }
2657                         else
2658                         {
2659                                 theChunk++;
2660                         }
2661                 }
2662
2663                 // Delete the entry in the filestructure
2664                 if(found)
2665                 {
2666                         tn->level0[chunkInInode & YAFFS_TNODES_LEVEL0_MASK] = 0;
2667                 }
2668     }
2669     else
2670     {
2671         //T(("No level 0 found for %d\n", chunkInInode));
2672     }
2673
2674     if(!found)
2675     {
2676         //T(("Could not find %d to delete\n",chunkInInode));
2677     }
2678     return found ? theChunk : -1;
2679 }
2680
2681
2682 #ifdef YAFFS_PARANOID
2683
2684 static int yaffs_CheckFileSanity(yaffs_Object *in)
2685 {
2686         int chunk;
2687         int nChunks;
2688         int fSize;
2689         int failed = 0;
2690         int objId;
2691         yaffs_Tnode *tn;
2692     yaffs_Tags localTags;
2693     yaffs_Tags *tags = &localTags;
2694     int theChunk;
2695     int chunkDeleted;
2696
2697
2698         if(in->variantType != YAFFS_OBJECT_TYPE_FILE)
2699         {
2700                 //T(("Object not a file\n"));
2701                 return YAFFS_FAIL;
2702         }
2703
2704         objId = in->objectId;
2705         fSize  = in->variant.fileVariant.fileSize;
2706         nChunks = (fSize + in->myDev->nBytesPerChunk -1)/in->myDev->nBytesPerChunk;
2707
2708         for(chunk = 1; chunk <= nChunks; chunk++)
2709         {
2710                 tn = yaffs_FindLevel0Tnode(in->myDev,&in->variant.fileVariant, chunk);
2711
2712                 if(tn)
2713                 {
2714
2715                         theChunk = tn->level0[chunk & YAFFS_TNODES_LEVEL0_MASK] << in->myDev->chunkGroupBits;
2716
2717
2718                                 yaffs_ReadChunkTagsFromNAND(in->myDev,theChunk,tags,&chunkDeleted);
2719                                 if(yaffs_TagsMatch(tags,in->objectId,chunk,chunkDeleted))
2720                                 {
2721                                         // found it;
2722
2723                                 }
2724                                 else
2725                                 {
2726                                         //T(("File problem file [%d,%d] NAND %d  tags[%d,%d]\n",
2727                                         //              objId,chunk,theChunk,tags->chunkId,tags->objectId);
2728
2729                                         failed = 1;
2730
2731                                 }
2732
2733                 }
2734                 else
2735                 {
2736                         //T(("No level 0 found for %d\n", chunk));
2737                 }
2738         }
2739
2740         return failed ? YAFFS_FAIL : YAFFS_OK;
2741 }
2742
2743 #endif
2744
2745 static int yaffs_PutChunkIntoFile(yaffs_Object *in,int chunkInInode, int chunkInNAND, int inScan)
2746 {
2747         yaffs_Tnode *tn;
2748         yaffs_Device *dev = in->myDev;
2749         int existingChunk;
2750         yaffs_Tags existingTags;
2751         yaffs_Tags newTags;
2752         unsigned existingSerial, newSerial;
2753
2754         int newChunkDeleted;
2755
2756
2757         tn = yaffs_AddOrFindLevel0Tnode(dev,&in->variant.fileVariant, chunkInInode);
2758         if(!tn)
2759         {
2760                 return YAFFS_FAIL;
2761         }
2762
2763         existingChunk = tn->level0[chunkInInode & YAFFS_TNODES_LEVEL0_MASK];
2764
2765         if(inScan)
2766         {
2767                 // If we're scanning then we need to test for duplicates
2768                 // NB This does not need to be efficient since it should only ever
2769                 // happen when the power fails during a write, then only one
2770                 // chunk should ever be affected.
2771
2772
2773                 if(existingChunk != 0)
2774                 {
2775                         // NB Right now existing chunk will not be real chunkId if the device >= 32MB
2776                         //    thus we have to do a FindChunkInFile to get the real chunk id.
2777                         //
2778                         // We have a duplicate now we need to decide which one to use
2779                         // To do this we get both sets of tags and compare serial numbers.
2780                         yaffs_ReadChunkTagsFromNAND(dev,chunkInNAND, &newTags,&newChunkDeleted);
2781
2782
2783                         // Do a proper find
2784                         existingChunk = yaffs_FindChunkInFile(in,chunkInInode, &existingTags);
2785
2786                         if(existingChunk <=0)
2787                         {
2788                                 //Hoosterman - how did this happen?
2789
2790                                 T(YAFFS_TRACE_ERROR, (TSTR("yaffs tragedy: existing chunk < 0 in scan" TENDSTR)));
2791
2792                         }
2793
2794
2795                         // NB The deleted flags should be false, otherwise the chunks will
2796                         // not be loaded during a scan
2797
2798                         newSerial = newTags.serialNumber;
2799                         existingSerial = existingTags.serialNumber;
2800
2801                         if( existingChunk <= 0 ||
2802                             ((existingSerial+1) & 3) == newSerial)
2803                         {
2804                                 // Use new
2805                                 // Delete the old one and drop through to update the tnode
2806                                 yaffs_DeleteChunk(dev,existingChunk,1);
2807                         }
2808                         else
2809                         {
2810                                 // Use existing.
2811                                 // Delete the new one and return early so that the tnode isn't changed
2812                                 yaffs_DeleteChunk(dev,chunkInNAND,1);
2813                                 return YAFFS_OK;
2814                         }
2815                 }
2816
2817         }
2818
2819         if(existingChunk == 0)
2820         {
2821                 in->nDataChunks++;
2822         }
2823
2824         tn->level0[chunkInInode & YAFFS_TNODES_LEVEL0_MASK] = (chunkInNAND >> dev->chunkGroupBits);
2825
2826         return YAFFS_OK;
2827 }
2828
2829
2830
2831 int yaffs_ReadChunkDataFromObject(yaffs_Object *in,int chunkInInode, __u8 *buffer)
2832 {
2833     int chunkInNAND = yaffs_FindChunkInFile(in,chunkInInode,NULL);
2834
2835     if(chunkInNAND >= 0)
2836     {
2837                 return yaffs_ReadChunkFromNAND(in->myDev,chunkInNAND,buffer,NULL,1);
2838         }
2839         else
2840         {
2841                 memset(buffer,0,YAFFS_BYTES_PER_CHUNK);
2842                 return 0;
2843         }
2844
2845 }
2846
2847
2848 static void yaffs_DeleteChunk(yaffs_Device *dev,int chunkId,int markNAND)
2849 {
2850         int block;
2851         int page;
2852         yaffs_Spare spare;
2853         yaffs_BlockInfo *bi;
2854
2855         if(chunkId <= 0) return;
2856
2857         dev->nDeletions++;
2858         block = chunkId / dev->nChunksPerBlock;
2859         page = chunkId % dev->nChunksPerBlock;
2860
2861         if(markNAND)
2862         {
2863                 yaffs_SpareInitialise(&spare);
2864
2865 #ifdef CONFIG_MTD_NAND_VERIFY_WRITE
2866
2867                 //read data before write, to ensure correct ecc
2868                 //if we're using MTD verification under Linux
2869                 yaffs_ReadChunkFromNAND(dev,chunkId,NULL,&spare,0);
2870 #endif
2871
2872                 spare.pageStatus = 0; // To mark it as deleted.
2873
2874
2875                 yaffs_WriteChunkToNAND(dev,chunkId,NULL,&spare);
2876                 yaffs_HandleUpdateChunk(dev,chunkId,&spare);
2877         }
2878         else
2879         {
2880                         dev->nUnmarkedDeletions++;
2881         }
2882
2883         bi = yaffs_GetBlockInfo(dev,block);
2884
2885
2886         // Pull out of the management area.
2887         // If the whole block became dirty, this will kick off an erasure.
2888         if(     bi->blockState == YAFFS_BLOCK_STATE_ALLOCATING ||
2889             bi->blockState == YAFFS_BLOCK_STATE_FULL)
2890         {
2891                 dev->nFreeChunks++;
2892
2893                 yaffs_ClearChunkBit(dev,block,page);
2894                 bi->pagesInUse--;
2895
2896                 if(bi->pagesInUse == 0 &&
2897                bi->blockState == YAFFS_BLOCK_STATE_FULL)
2898             {
2899                 yaffs_BlockBecameDirty(dev,block);
2900             }
2901
2902         }
2903         else
2904         {
2905                 // T(("Bad news deleting chunk %d\n",chunkId));
2906         }
2907
2908 }
2909
2910
2911
2912
2913 int yaffs_WriteChunkDataToObject(yaffs_Object *in,int chunkInInode, const __u8 *buffer,int nBytes,int useReserve)
2914 {
2915         // Find old chunk Need to do this to get serial number
2916         // Write new one and patch into tree.
2917         // Invalidate old tags.
2918
2919     int prevChunkId;
2920     yaffs_Tags prevTags;
2921
2922     int newChunkId;
2923     yaffs_Tags newTags;
2924
2925     yaffs_Device *dev = in->myDev;
2926
2927         yaffs_CheckGarbageCollection(dev);
2928
2929         // Get the previous chunk at this location in the file if it exists
2930     prevChunkId  = yaffs_FindChunkInFile(in,chunkInInode,&prevTags);
2931
2932     // Set up new tags
2933         newTags.chunkId = chunkInInode;
2934         newTags.objectId = in->objectId;
2935         newTags.serialNumber = (prevChunkId >= 0) ? prevTags.serialNumber + 1 : 1;
2936         newTags.byteCount = nBytes;
2937         newTags.unusedStuff = 0xFFFFFFFF;
2938
2939         yaffs_CalcTagsECC(&newTags);
2940
2941         newChunkId = yaffs_WriteNewChunkWithTagsToNAND(dev,buffer,&newTags,useReserve);
2942         if(newChunkId >= 0)
2943         {
2944                 yaffs_PutChunkIntoFile(in,chunkInInode,newChunkId,0);
2945
2946
2947                 if(prevChunkId >= 0)
2948                 {
2949                         yaffs_DeleteChunk(dev,prevChunkId,1);
2950
2951                 }
2952
2953                 yaffs_CheckFileSanity(in);
2954         }
2955         return newChunkId;
2956
2957
2958
2959
2960
2961 }
2962
2963
2964 // UpdateObjectHeader updates the header on NAND for an object.
2965 // If name is not NULL, then that new name is used.
2966 //
2967 int yaffs_UpdateObjectHeader(yaffs_Object *in,const char *name, int force)
2968 {
2969
2970         yaffs_Device *dev = in->myDev;
2971
2972     int prevChunkId;
2973
2974     int newChunkId;
2975     yaffs_Tags newTags;
2976     __u8 bufferNew[YAFFS_BYTES_PER_CHUNK];
2977     __u8 bufferOld[YAFFS_BYTES_PER_CHUNK];
2978
2979     yaffs_ObjectHeader *oh = (yaffs_ObjectHeader *)bufferNew;
2980     yaffs_ObjectHeader *ohOld = (yaffs_ObjectHeader *)bufferOld;
2981
2982
2983     if(!in->fake || force)
2984     {
2985
2986                 yaffs_CheckGarbageCollection(dev);
2987
2988                 memset(bufferNew,0xFF,YAFFS_BYTES_PER_CHUNK);
2989
2990                 prevChunkId = in->chunkId;
2991
2992                 if(prevChunkId >= 0)
2993                 {
2994                         yaffs_ReadChunkFromNAND(dev,prevChunkId,bufferOld,NULL,1);
2995                 }
2996
2997                 // Header data
2998                 oh->type = in->variantType;
2999
3000                 oh->st_mode = in->st_mode;
3001
3002 #ifdef CONFIG_YAFFS_WINCE
3003                 oh->win_atime[0] = in->win_atime[0];
3004                 oh->win_ctime[0] = in->win_ctime[0];
3005                 oh->win_mtime[0] = in->win_mtime[0];
3006                 oh->win_atime[1] = in->win_atime[1];
3007                 oh->win_ctime[1] = in->win_ctime[1];
3008                 oh->win_mtime[1] = in->win_mtime[1];
3009 #else
3010                 oh->st_uid = in->st_uid;
3011                 oh->st_gid = in->st_gid;
3012                 oh->st_atime = in->st_atime;
3013                 oh->st_mtime = in->st_mtime;
3014                 oh->st_ctime = in->st_ctime;
3015                 oh->st_rdev = in->st_rdev;
3016 #endif
3017                 if(in->parent)
3018                 {
3019                         oh->parentObjectId = in->parent->objectId;
3020                 }
3021                 else
3022                 {
3023                         oh->parentObjectId = 0;
3024                 }
3025
3026                 //oh->sum = in->sum;
3027                 if(name && *name)
3028                 {
3029                         memset(oh->name,0,YAFFS_MAX_NAME_LENGTH + 1);
3030                         strncpy(oh->name,name,YAFFS_MAX_NAME_LENGTH);
3031                 }
3032                 else if(prevChunkId)
3033                 {
3034                         memcpy(oh->name, ohOld->name,YAFFS_MAX_NAME_LENGTH + 1);
3035                 }
3036                 else
3037                 {
3038                         memset(oh->name,0,YAFFS_MAX_NAME_LENGTH + 1);
3039                 }
3040
3041                 switch(in->variantType)
3042                 {
3043                         case YAFFS_OBJECT_TYPE_UNKNOWN:
3044                                 // Should not happen
3045                                 break;
3046                         case YAFFS_OBJECT_TYPE_FILE:
3047                                 oh->fileSize = in->variant.fileVariant.fileSize;
3048                                 break;
3049                         case YAFFS_OBJECT_TYPE_HARDLINK:
3050                                 oh->equivalentObjectId = in->variant.hardLinkVariant.equivalentObjectId;
3051                                 break;
3052                         case YAFFS_OBJECT_TYPE_SPECIAL:
3053                                 // Do nothing
3054                                 break;
3055                         case YAFFS_OBJECT_TYPE_DIRECTORY:
3056                                 // Do nothing
3057                                 break;
3058                         case YAFFS_OBJECT_TYPE_SYMLINK:
3059                                 strncpy(oh->alias,in->variant.symLinkVariant.alias,YAFFS_MAX_ALIAS_LENGTH);
3060                                 oh->alias[YAFFS_MAX_ALIAS_LENGTH] = 0;
3061                                 break;
3062                 }
3063
3064                 // Tags
3065                 in->serial++;
3066                 newTags.chunkId = 0;
3067                 newTags.objectId = in->objectId;
3068                 newTags.serialNumber = in->serial;
3069                 newTags.byteCount =   0xFFFFFFFF;
3070                 newTags.unusedStuff = 0xFFFFFFFF;
3071
3072                 yaffs_CalcTagsECC(&newTags);
3073
3074
3075                 // Create new chunk in NAND
3076                 newChunkId = yaffs_WriteNewChunkWithTagsToNAND(dev,bufferNew,&newTags, (prevChunkId >= 0) ? 1 : 0 );
3077
3078                 if(newChunkId >= 0)
3079                 {
3080
3081                         in->chunkId = newChunkId;
3082
3083                         if(prevChunkId >= 0)
3084                         {
3085                                 yaffs_DeleteChunk(dev,prevChunkId,1);
3086                         }
3087
3088                         in->dirty = 0;
3089                 }
3090
3091                 return newChunkId;
3092
3093     }
3094     return 0;
3095 }
3096
3097
3098 /////////////////////// Short Operations Cache ////////////////////////////////
3099 //      In many siturations where there is no high level buffering (eg WinCE) a lot of
3100 //      reads might be short sequential reads, and a lot of writes may be short
3101 //  sequential writes. eg. scanning/writing a jpeg file.
3102 //      In these cases, a short read/write cache can provide a huge perfomance benefit
3103 //  with dumb-as-a-rock code.
3104 //  There are a limited number (~10) of cache chunks per device so that we don't
3105 //  need a very intelligent search.
3106
3107
3108
3109
3110
3111 static void yaffs_FlushFilesChunkCache(yaffs_Object *obj)
3112 {
3113         yaffs_Device *dev = obj->myDev;
3114         int lowest;
3115         int i;
3116         yaffs_ChunkCache *cache;
3117         int chunkWritten;
3118         int nBytes;
3119         int nCaches = obj->myDev->nShortOpCaches;
3120
3121         if  (nCaches > 0)
3122         {
3123                 do{
3124                         cache = NULL;
3125
3126                         // Find the dirty cache for this object with the lowest chunk id.
3127                         for(i = 0; i < nCaches; i++)
3128                         {
3129                                 if(dev->srCache[i].object == obj &&
3130                                 dev->srCache[i].dirty)
3131                                 {
3132                                         if(!cache ||  dev->srCache[i].chunkId < lowest)
3133                                         {
3134                                                 cache = &dev->srCache[i];
3135                                                 lowest = cache->chunkId;
3136                                         }
3137                                 }
3138                         }
3139
3140                         if(cache)
3141                         {
3142                                 //Write it out
3143
3144 #if 0
3145                                 nBytes = cache->object->variant.fileVariant.fileSize - ((cache->chunkId -1) * YAFFS_BYTES_PER_CHUNK);
3146
3147                                 if(nBytes > YAFFS_BYTES_PER_CHUNK)
3148                                 {
3149                                         nBytes= YAFFS_BYTES_PER_CHUNK;
3150                                 }
3151 #endif
3152                                 chunkWritten = yaffs_WriteChunkDataToObject(cache->object,
3153                                                                                                                         cache->chunkId,
3154                                                                                                                         cache->data,
3155                                                                                                                         cache->nBytes,1);
3156
3157                                 cache->dirty = 0;
3158                                 cache->object = NULL;
3159                         }
3160
3161                 } while(cache && chunkWritten > 0);
3162
3163                 if(cache)
3164                 {
3165                         //Hoosterman, disk full while writing cache out.
3166                         T(YAFFS_TRACE_ERROR, (TSTR("yaffs tragedy: no space during cache write" TENDSTR)));
3167
3168                 }
3169         }
3170
3171 }
3172
3173
3174 // Grab us a chunk for use.
3175 // First look for an empty one.
3176 // Then look for the least recently used non-dirty one.
3177 // Then look for the least recently used dirty one...., flush and look again.
3178 static yaffs_ChunkCache *yaffs_GrabChunkCacheWorker(yaffs_Device *dev)
3179 {
3180         int i;
3181         int usage;
3182         int theOne;
3183
3184         if(dev->nShortOpCaches > 0)
3185         {
3186                 for(i = 0; i < dev->nShortOpCaches; i++)
3187                 {
3188                         if(!dev->srCache[i].object)
3189                         {
3190                                 //T(("Grabbing empty %d\n",i));
3191
3192                                 //printf("Grabbing empty %d\n",i);
3193
3194                                 return &dev->srCache[i];
3195                         }
3196                 }
3197
3198                 return NULL;
3199
3200                 theOne = -1;
3201                 usage = 0; // just to stop the compiler grizzling
3202
3203                 for(i = 0; i < dev->nShortOpCaches; i++)
3204                 {
3205                         if(!dev->srCache[i].dirty &&
3206                         ((dev->srCache[i].lastUse < usage  && theOne >= 0)||
3207                                 theOne < 0))
3208                         {
3209                                 usage = dev->srCache[i].lastUse;
3210                                 theOne = i;
3211                         }
3212                 }
3213
3214                 //T(("Grabbing non-empty %d\n",theOne));
3215
3216                 //if(theOne >= 0) printf("Grabbed non-empty cache %d\n",theOne);
3217
3218                 return  theOne >= 0 ?  &dev->srCache[theOne] : NULL;
3219         }
3220         else
3221         {
3222                 return NULL;
3223         }
3224
3225 }
3226
3227
3228 static yaffs_ChunkCache *yaffs_GrabChunkCache(yaffs_Device *dev)
3229 {
3230         yaffs_ChunkCache *cache;
3231         yaffs_Object *theObj;
3232         int usage;
3233         int i;
3234         int pushout;
3235
3236         if(dev->nShortOpCaches > 0)
3237         {
3238                 // Try find a non-dirty one...
3239
3240                 cache = yaffs_GrabChunkCacheWorker(dev);
3241
3242                 if(!cache)
3243                 {
3244                         // They were all dirty, find the last recently used object and flush
3245                         // its cache, then  find again.
3246                         // NB what's here is not very accurate, we actually flush the object
3247                         // the last recently used page.
3248
3249                         theObj = dev->srCache[0].object;
3250                         usage = dev->srCache[0].lastUse;
3251                         cache = &dev->srCache[0];
3252                         pushout = 0;
3253
3254                         for(i = 1; i < dev->nShortOpCaches; i++)
3255                         {
3256                                 if( dev->srCache[i].object &&
3257                                         dev->srCache[i].lastUse < usage)
3258                                 {
3259                                         usage  = dev->srCache[i].lastUse;
3260                                         theObj = dev->srCache[i].object;
3261                                         cache = &dev->srCache[i];
3262                                         pushout = i;
3263                                 }
3264                         }
3265
3266                         if(!cache || cache->dirty)
3267                         {
3268
3269                                 //printf("Dirty ");
3270                                 yaffs_FlushFilesChunkCache(theObj);
3271
3272                                 // Try again
3273                                 cache = yaffs_GrabChunkCacheWorker(dev);
3274                         }
3275                         else
3276                         {
3277                                 //printf(" pushout %d\n",pushout);
3278                         }
3279
3280                 }
3281
3282                 return cache;
3283         }
3284         else
3285                 return NULL;
3286
3287 }
3288
3289
3290 // Find a cached chunk
3291 static yaffs_ChunkCache *yaffs_FindChunkCache(const yaffs_Object *obj, int chunkId)
3292 {
3293         yaffs_Device *dev = obj->myDev;
3294         int i;
3295         if(dev->nShortOpCaches > 0)
3296         {
3297                 for(i = 0; i < dev->nShortOpCaches; i++)
3298                 {
3299                         if(dev->srCache[i].object == obj &&
3300                         dev->srCache[i].chunkId == chunkId)
3301                         {
3302                                 dev->cacheHits++;
3303
3304                                 return &dev->srCache[i];
3305                         }
3306                 }
3307         }
3308         return NULL;
3309 }
3310
3311 // Mark the chunk for the least recently used algorithym
3312 static void yaffs_UseChunkCache(yaffs_Device *dev, yaffs_ChunkCache *cache, int isAWrite)
3313 {
3314
3315         if(dev->nShortOpCaches > 0)
3316         {
3317                 if( dev->srLastUse < 0 ||
3318                         dev->srLastUse > 100000000)
3319                 {
3320                         // Reset the cache usages
3321                         int i;
3322                         for(i = 1; i < dev->nShortOpCaches; i++)
3323                         {
3324                                 dev->srCache[i].lastUse = 0;
3325                         }
3326                         dev->srLastUse = 0;
3327                 }
3328
3329                 dev->srLastUse++;
3330
3331                 cache->lastUse = dev->srLastUse;
3332
3333                 if(isAWrite)
3334                 {
3335                         cache->dirty = 1;
3336                 }
3337         }
3338 }
3339
3340 // Invalidate a single cache page.
3341 // Do this when a whole page gets written,
3342 // ie the short cache for this page is no longer valid.
3343 static void yaffs_InvalidateChunkCache(yaffs_Object *object, int chunkId)
3344 {
3345         if(object->myDev->nShortOpCaches > 0)
3346         {
3347                 yaffs_ChunkCache *cache = yaffs_FindChunkCache(object,chunkId);
3348
3349                 if(cache)
3350                 {
3351                         cache->object = NULL;
3352                 }
3353         }
3354 }
3355
3356
3357 // Invalidate all the cache pages associated with this object
3358 // Do this whenever ther file is deleted or resized.
3359 static void yaffs_InvalidateWholeChunkCache(yaffs_Object *in)
3360 {
3361         int i;
3362         yaffs_Device *dev = in->myDev;
3363
3364         if(dev->nShortOpCaches > 0)
3365         {
3366                 // Now invalidate it.
3367                 for(i = 0; i < dev->nShortOpCaches; i++)
3368                 {
3369                         if(dev->srCache[i].object == in)
3370                         {
3371                                 dev->srCache[i].object = NULL;
3372                         }
3373                 }
3374         }
3375 }
3376
3377
3378
3379
3380
3381 ///////////////////////// File read/write ///////////////////////////////
3382 // Read and write have very similar structures.
3383 // In general the read/write has three parts to it
3384 // * An incomplete chunk to start with (if the read/write is not chunk-aligned)
3385 // * Some complete chunks
3386 // * An incomplete chunk to end off with
3387 //
3388 // Curve-balls: the first chunk might also be the last chunk.
3389
3390 int yaffs_ReadDataFromFile(yaffs_Object *in, __u8 * buffer, __u32 offset, int nBytes)
3391 {
3392
3393
3394         int chunk;
3395         int start;
3396         int nToCopy;
3397         int n = nBytes;
3398         int nDone = 0;
3399         yaffs_ChunkCache *cache;
3400
3401         yaffs_Device *dev;
3402
3403         dev = in->myDev;
3404
3405         while(n > 0)
3406         {
3407                 chunk = offset / YAFFS_BYTES_PER_CHUNK + 1; // The first chunk is 1
3408                 start = offset % YAFFS_BYTES_PER_CHUNK;
3409
3410                 // OK now check for the curveball where the start and end are in
3411                 // the same chunk.
3412                 if(     (start + n) < YAFFS_BYTES_PER_CHUNK)
3413                 {
3414                         nToCopy = n;
3415                 }
3416                 else
3417                 {
3418                         nToCopy = YAFFS_BYTES_PER_CHUNK - start;
3419                 }
3420
3421                 cache = yaffs_FindChunkCache(in,chunk);
3422
3423                 // If the chunk is already in the cache or it is less than a whole chunk
3424                 // then use the cache (if there is caching)
3425                 // else bypass the cache.
3426                 if( cache || nToCopy != YAFFS_BYTES_PER_CHUNK)
3427                 {
3428                         if(dev->nShortOpCaches > 0)
3429                         {
3430
3431                                 // If we can't find the data in the cache, then load it up.
3432
3433                                 if(!cache)
3434                                 {
3435                                         cache = yaffs_GrabChunkCache(in->myDev);
3436                                         cache->object = in;
3437                                         cache->chunkId = chunk;
3438                                         cache->dirty = 0;
3439                                         yaffs_ReadChunkDataFromObject(in,chunk,cache->data);
3440                                         cache->nBytes = 0;
3441                                 }
3442
3443                                 yaffs_UseChunkCache(dev,cache,0);
3444
3445                                 memcpy(buffer,&cache->data[start],nToCopy);
3446                         }
3447                         else
3448                         {
3449                                 // Read into the local buffer then copy...
3450                                 yaffs_ReadChunkDataFromObject(in,chunk,dev->localBuffer);
3451                                 memcpy(buffer,&dev->localBuffer[start],nToCopy);
3452                         }
3453
3454                 }
3455                 else
3456                 {
3457 #ifdef CONFIG_YAFFS_WINCE
3458
3459                         // Under WinCE can't do direct transfer. Need to use a local buffer.
3460                         // This is because we otherwise screw up WinCE's memory mapper
3461                         yaffs_ReadChunkDataFromObject(in,chunk,dev->localBuffer);
3462                         memcpy(buffer,dev->localBuffer,YAFFS_BYTES_PER_CHUNK);
3463 #else
3464                         // A full chunk. Read directly into the supplied buffer.
3465                         yaffs_ReadChunkDataFromObject(in,chunk,buffer);
3466 #endif
3467                 }
3468
3469                 n -= nToCopy;
3470                 offset += nToCopy;
3471                 buffer += nToCopy;
3472                 nDone += nToCopy;
3473
3474         }
3475
3476         return nDone;
3477 }
3478
3479
3480
3481 int yaffs_WriteDataToFile(yaffs_Object *in,const __u8 * buffer, __u32 offset, int nBytes)
3482 {
3483
3484         int chunk;
3485         int start;
3486         int nToCopy;
3487         int n = nBytes;
3488         int nDone = 0;
3489         int nToWriteBack;
3490         int startOfWrite = offset;
3491         int chunkWritten = 0;
3492         int nBytesRead;
3493
3494         yaffs_Device *dev;
3495
3496         dev = in->myDev;
3497
3498
3499         while(n > 0 && chunkWritten >= 0)
3500         {
3501                 chunk = offset / YAFFS_BYTES_PER_CHUNK + 1;
3502                 start = offset % YAFFS_BYTES_PER_CHUNK;
3503
3504
3505                 // OK now check for the curveball where the start and end are in
3506                 // the same chunk.
3507
3508                 if(     (start + n) < YAFFS_BYTES_PER_CHUNK)
3509                 {
3510                         nToCopy = n;
3511
3512                         // Now folks, to calculate how many bytes to write back....
3513                         // If we're overwriting and not writing to then end of file then
3514                         // we need to write back as much as was there before.
3515
3516                         nBytesRead = in->variant.fileVariant.fileSize - ((chunk -1) * YAFFS_BYTES_PER_CHUNK);
3517
3518                         if(nBytesRead > YAFFS_BYTES_PER_CHUNK)
3519                         {
3520                                 nBytesRead = YAFFS_BYTES_PER_CHUNK;
3521                         }
3522
3523                         nToWriteBack = (nBytesRead > (start + n)) ? nBytesRead : (start +n);
3524
3525                 }
3526                 else
3527                 {
3528                         nToCopy = YAFFS_BYTES_PER_CHUNK - start;
3529                         nToWriteBack = YAFFS_BYTES_PER_CHUNK;
3530                 }
3531
3532                 if(nToCopy != YAFFS_BYTES_PER_CHUNK)
3533                 {
3534                         // An incomplete start or end chunk (or maybe both start and end chunk)
3535                         if(dev->nShortOpCaches > 0)
3536                         {
3537                                 yaffs_ChunkCache *cache;
3538                                 // If we can't find the data in the cache, then load it up.
3539                                 cache = yaffs_FindChunkCache(in,chunk);
3540                                 if(!cache && yaffs_CheckSpaceForChunkCache(in->myDev))
3541                                 {
3542                                         cache = yaffs_GrabChunkCache(in->myDev);
3543                                         cache->object = in;
3544                                         cache->chunkId = chunk;
3545                                         cache->dirty = 0;
3546                                         yaffs_ReadChunkDataFromObject(in,chunk,cache->data);
3547                                 }
3548
3549                                 if(cache)
3550                                 {
3551                                         yaffs_UseChunkCache(dev,cache,1);
3552                                         memcpy(&cache->data[start],buffer,nToCopy);
3553                                         cache->nBytes = nToWriteBack;
3554                                 }
3555                                 else
3556                                 {
3557                                         chunkWritten = -1; // fail the write
3558                                 }
3559                         }
3560                         else
3561                         {
3562                                 // An incomplete start or end chunk (or maybe both start and end chunk)
3563                                 // Read into the local buffer then copy, then copy over and write back.
3564
3565                                 yaffs_ReadChunkDataFromObject(in,chunk,dev->localBuffer);
3566
3567                                 memcpy(&dev->localBuffer[start],buffer,nToCopy);
3568
3569                                 chunkWritten = yaffs_WriteChunkDataToObject(in,chunk,dev->localBuffer,nToWriteBack,0);
3570
3571                                 //T(("Write with readback to chunk %d %d  start %d  copied %d wrote back %d\n",chunk,chunkWritten,start, nToCopy, nToWriteBack));
3572                         }
3573
3574                 }
3575                 else
3576                 {
3577
3578 #ifdef CONFIG_YAFFS_WINCE
3579                         // Under WinCE can't do direct transfer. Need to use a local buffer.
3580                         // This is because we otherwise screw up WinCE's memory mapper
3581                         memcpy(dev->localBuffer,buffer,YAFFS_BYTES_PER_CHUNK);
3582                         chunkWritten = yaffs_WriteChunkDataToObject(in,chunk,dev->localBuffer,YAFFS_BYTES_PER_CHUNK,0);
3583 #else
3584                         // A full chunk. Write directly from the supplied buffer.
3585                         chunkWritten = yaffs_WriteChunkDataToObject(in,chunk,buffer,YAFFS_BYTES_PER_CHUNK,0);
3586 #endif
3587                         // Since we've overwritten the cached data, we better invalidate it.
3588                         yaffs_InvalidateChunkCache(in,chunk);
3589                         //T(("Write to chunk %d %d\n",chunk,chunkWritten));
3590                 }
3591
3592                 if(chunkWritten >= 0)
3593                 {
3594                         n -= nToCopy;
3595                         offset += nToCopy;
3596                         buffer += nToCopy;
3597                         nDone += nToCopy;
3598                 }
3599
3600         }
3601
3602         // Update file object
3603
3604         if((startOfWrite + nDone) > in->variant.fileVariant.fileSize)
3605         {
3606                 in->variant.fileVariant.fileSize = (startOfWrite + nDone);
3607         }
3608
3609         in->dirty = 1;
3610
3611         return nDone;
3612 }
3613
3614
3615 int yaffs_ResizeFile(yaffs_Object *in, int newSize)
3616 {
3617         int i;
3618         int chunkId;
3619         int oldFileSize = in->variant.fileVariant.fileSize;
3620         int sizeOfPartialChunk = newSize % YAFFS_BYTES_PER_CHUNK;
3621
3622         yaffs_Device *dev = in->myDev;
3623
3624
3625         yaffs_FlushFilesChunkCache(in);
3626         yaffs_InvalidateWholeChunkCache(in);
3627
3628         if(in->variantType != YAFFS_OBJECT_TYPE_FILE)
3629         {
3630                 return yaffs_GetFileSize(in);
3631         }
3632
3633         if(newSize < oldFileSize)
3634         {
3635
3636                 int lastDel = 1 + (oldFileSize-1)/YAFFS_BYTES_PER_CHUNK;
3637
3638                 int startDel = 1 + (newSize + YAFFS_BYTES_PER_CHUNK - 1)/
3639                                                         YAFFS_BYTES_PER_CHUNK;
3640
3641                 // Delete backwards so that we don't end up with holes if
3642                 // power is lost part-way through the operation.
3643                 for(i = lastDel; i >= startDel; i--)
3644                 {
3645                         // NB this could be optimised somewhat,
3646                         // eg. could retrieve the tags and write them without
3647                         // using yaffs_DeleteChunk
3648
3649                         chunkId = yaffs_FindAndDeleteChunkInFile(in,i,NULL);
3650                         if(chunkId < (dev->startBlock * 32) || chunkId >= ((dev->endBlock+1) * 32))
3651                         {
3652                                 //T(("Found daft chunkId %d for %d\n",chunkId,i));
3653                         }
3654                         else
3655                         {
3656                                 in->nDataChunks--;
3657                                 yaffs_DeleteChunk(dev,chunkId,1);
3658                         }
3659                 }
3660
3661
3662                 if(sizeOfPartialChunk != 0)
3663                 {
3664                         int lastChunk = 1+ newSize/YAFFS_BYTES_PER_CHUNK;
3665
3666                         // Got to read and rewrite the last chunk with its new size.
3667                         // NB Got to zero pad to nuke old data
3668                         yaffs_ReadChunkDataFromObject(in,lastChunk,dev->localBuffer);
3669                         memset(dev->localBuffer + sizeOfPartialChunk,0, YAFFS_BYTES_PER_CHUNK - sizeOfPartialChunk);
3670
3671                         yaffs_WriteChunkDataToObject(in,lastChunk,dev->localBuffer,sizeOfPartialChunk,1);
3672
3673                 }
3674
3675                 in->variant.fileVariant.fileSize = newSize;
3676
3677                 yaffs_PruneFileStructure(dev,&in->variant.fileVariant);
3678
3679                 return newSize;
3680
3681         }
3682         else
3683         {
3684                 return oldFileSize;
3685         }
3686 }
3687
3688
3689 loff_t yaffs_GetFileSize(yaffs_Object *obj)
3690 {
3691         obj = yaffs_GetEquivalentObject(obj);
3692
3693         switch(obj->variantType)
3694         {
3695                 case YAFFS_OBJECT_TYPE_FILE:
3696                         return obj->variant.fileVariant.fileSize;
3697                 case YAFFS_OBJECT_TYPE_SYMLINK:
3698                         return strlen(obj->variant.symLinkVariant.alias);
3699                 default:
3700                         return 0;
3701         }
3702 }
3703
3704
3705
3706 // yaffs_FlushFile() updates the file's
3707 // objectId in NAND
3708
3709 int yaffs_FlushFile(yaffs_Object *in, int updateTime)
3710 {
3711         int retVal;
3712         if(in->dirty)
3713         {
3714                 //T(("flushing object header\n"));
3715
3716                 yaffs_FlushFilesChunkCache(in);
3717                 if(updateTime)
3718                 {
3719 #ifdef CONFIG_YAFFS_WINCE
3720                         yfsd_WinFileTimeNow(in->win_mtime);
3721 #else
3722                         in->st_mtime = Y_CURRENT_TIME;
3723 #endif
3724                 }
3725
3726                 retVal = (yaffs_UpdateObjectHeader(in,NULL,0) >= 0)? YAFFS_OK : YAFFS_FAIL;
3727         }
3728         else
3729         {
3730                 retVal = YAFFS_OK;
3731         }
3732
3733         return retVal;
3734
3735 }
3736
3737
3738 static int yaffs_DoGenericObjectDeletion(yaffs_Object *in)
3739 {
3740
3741         // First off, invalidate the file's data in the cache, without flushing.
3742         yaffs_InvalidateWholeChunkCache(in);
3743
3744         yaffs_RemoveObjectFromDirectory(in);
3745         yaffs_DeleteChunk(in->myDev,in->chunkId,1);
3746 #ifdef __KERNEL__
3747         if(in->myInode)
3748         {
3749                 in->myInode->u.generic_ip = NULL;
3750                 in->myInode = 0;
3751         }
3752 #endif
3753         yaffs_FreeObject(in);
3754         return YAFFS_OK;
3755
3756 }
3757
3758 // yaffs_DeleteFile deletes the whole file data
3759 // and the inode associated with the file.
3760 // It does not delete the links associated with the file.
3761 static int yaffs_UnlinkFile(yaffs_Object *in)
3762 {
3763
3764 #ifdef CONFIG_YAFFS_DISABLE_BACKGROUND_DELETION
3765
3766         // Delete the file data & tnodes
3767
3768          yaffs_DeleteWorker(in, in->variant.fileVariant.top, in->variant.fileVariant.topLevel, 0,NULL);
3769
3770
3771         yaffs_FreeTnode(in->myDev,in->variant.fileVariant.top);
3772
3773         return  yaffs_DoGenericObjectDeletion(in);
3774 #else
3775         int retVal;
3776         int immediateDeletion=0;
3777         retVal = yaffs_ChangeObjectName(in, in->myDev->unlinkedDir,NULL,0);
3778         if(1 || // Ignore the result of the change name. This will only fail
3779                         // if the disk was completely full (an error condition)
3780                         // We ignore the error so we can delete files to recover the disk
3781            retVal == YAFFS_OK)
3782         {
3783                 //in->unlinked = 1;
3784                 //in->myDev->nUnlinkedFiles++;
3785                 //in->renameAllowed = 0;
3786 #ifdef __KERNEL__
3787                 if(!in->myInode)
3788                 {
3789                         immediateDeletion = 1;
3790
3791                 }
3792 #else
3793                 if(in->inUse <= 0)
3794                 {
3795                         immediateDeletion = 1;
3796
3797                 }
3798 #endif
3799
3800                 if(immediateDeletion)
3801                 {
3802                         T(YAFFS_TRACE_TRACING,(TSTR("yaffs: immediate deletion of file %d" TENDSTR),in->objectId));
3803                         in->deleted=1;
3804                         in->myDev->nDeletedFiles++;
3805                         yaffs_SoftDeleteFile(in);
3806                 }
3807
3808         }
3809         return retVal;
3810
3811
3812 #endif
3813 }
3814
3815 int yaffs_DeleteFile(yaffs_Object *in)
3816 {
3817         int retVal = YAFFS_OK;
3818
3819         if(in->nDataChunks > 0)
3820         {
3821                 // Use soft deletion
3822                 if(!in->unlinked)
3823                 {
3824                         retVal = yaffs_UnlinkFile(in);
3825                 }
3826                 if(retVal == YAFFS_OK &&
3827                 in->unlinked &&
3828                 !in->deleted)
3829                 {
3830                         in->deleted = 1;
3831                         in->myDev->nDeletedFiles++;
3832                         yaffs_SoftDeleteFile(in);
3833                 }
3834                 return in->deleted ? YAFFS_OK : YAFFS_FAIL;
3835         }
3836         else
3837         {
3838                 // The file has no data chunks so we toss it immediately
3839                 yaffs_FreeTnode(in->myDev,in->variant.fileVariant.top);
3840                 in->variant.fileVariant.top = NULL;
3841                 yaffs_DoGenericObjectDeletion(in);
3842
3843                 return YAFFS_OK;
3844         }
3845 }
3846
3847 static int yaffs_DeleteDirectory(yaffs_Object *in)
3848 {
3849         //First check that the directory is empty.
3850         if(list_empty(&in->variant.directoryVariant.children))
3851         {
3852                 return  yaffs_DoGenericObjectDeletion(in);
3853         }
3854
3855         return YAFFS_FAIL;
3856
3857 }
3858
3859 static int yaffs_DeleteSymLink(yaffs_Object *in)
3860 {
3861         YFREE(in->variant.symLinkVariant.alias);
3862
3863         return  yaffs_DoGenericObjectDeletion(in);
3864 }
3865
3866 static int yaffs_DeleteHardLink(yaffs_Object *in)
3867 {
3868         // remove this hardlink from the list assocaited with the equivalent
3869         // object
3870         list_del(&in->hardLinks);
3871         return  yaffs_DoGenericObjectDeletion(in);
3872 }
3873
3874
3875 static void yaffs_AbortHalfCreatedObject(yaffs_Object *obj)
3876 {
3877         switch(obj->variantType)
3878         {
3879                 case YAFFS_OBJECT_TYPE_FILE: yaffs_DeleteFile(obj); break;
3880                 case YAFFS_OBJECT_TYPE_DIRECTORY: yaffs_DeleteDirectory(obj); break;
3881                 case YAFFS_OBJECT_TYPE_SYMLINK: yaffs_DeleteSymLink(obj); break;
3882                 case YAFFS_OBJECT_TYPE_HARDLINK: yaffs_DeleteHardLink(obj); break;
3883                 case YAFFS_OBJECT_TYPE_SPECIAL: yaffs_DoGenericObjectDeletion(obj); break;
3884                 case YAFFS_OBJECT_TYPE_UNKNOWN: break; // should not happen.
3885         }
3886 }
3887
3888
3889 static int yaffs_UnlinkWorker(yaffs_Object *obj)
3890 {
3891
3892
3893         if(obj->variantType == YAFFS_OBJECT_TYPE_HARDLINK)
3894         {
3895                 return  yaffs_DeleteHardLink(obj);
3896         }
3897         else if(!list_empty(&obj->hardLinks))
3898         {
3899                 // Curve ball: We're unlinking an object that has a hardlink.
3900                 //
3901                 //      This problem arises because we are not strictly following
3902                 //  The Linux link/inode model.
3903                 //
3904                 // We can't really delete the object.
3905                 // Instead, we do the following:
3906                 // - Select a hardlink.
3907                 // - Unhook it from the hard links
3908                 // - Unhook it from its parent directory (so that the rename can work)
3909                 // - Rename the object to the hardlink's name.
3910                 // - Delete the hardlink
3911
3912
3913                 yaffs_Object *hl;
3914                 int retVal;
3915                 char name[YAFFS_MAX_NAME_LENGTH+1];
3916
3917                 hl = list_entry(obj->hardLinks.next,yaffs_Object,hardLinks);
3918
3919                 list_del_init(&hl->hardLinks);
3920                 list_del_init(&hl->siblings);
3921
3922                 yaffs_GetObjectName(hl,name,YAFFS_MAX_NAME_LENGTH+1);
3923
3924                 retVal = yaffs_ChangeObjectName(obj, hl->parent, name,0);
3925
3926                 if(retVal == YAFFS_OK)
3927                 {
3928                         retVal = yaffs_DoGenericObjectDeletion(hl);
3929                 }
3930                 return retVal;
3931
3932         }
3933         else
3934         {
3935                 switch(obj->variantType)
3936                 {
3937                         case YAFFS_OBJECT_TYPE_FILE:
3938                                 return yaffs_UnlinkFile(obj);
3939                                 break;
3940                         case YAFFS_OBJECT_TYPE_DIRECTORY:
3941                                 return yaffs_DeleteDirectory(obj);
3942                                 break;
3943                         case YAFFS_OBJECT_TYPE_SYMLINK:
3944                                 return yaffs_DeleteSymLink(obj);
3945                                 break;
3946                         case YAFFS_OBJECT_TYPE_HARDLINK:
3947                         case YAFFS_OBJECT_TYPE_UNKNOWN:
3948                         default:
3949                                 return YAFFS_FAIL;
3950                 }
3951         }
3952 }
3953
3954 int yaffs_Unlink(yaffs_Object *dir, const char *name)
3955 {
3956         yaffs_Object *obj;
3957
3958          obj = yaffs_FindObjectByName(dir,name);
3959
3960          if(obj && obj->unlinkAllowed)
3961          {
3962                 return yaffs_UnlinkWorker(obj);
3963          }
3964
3965          return YAFFS_FAIL;
3966
3967 }
3968
3969 //////////////// Initialisation Scanning /////////////////
3970
3971
3972
3973 // For now we use the SmartMedia check.
3974 // We look at the blockStatus byte in the first two chunks
3975 // These must be 0xFF to pass as OK.
3976 // todo: this function needs to be modifyable foir different NAND types
3977 // and different chunk sizes.  Suggest make this into a per-device configurable
3978 // function.
3979 static int yaffs_IsBlockBad(yaffs_Device *dev, int blk)
3980 {
3981         yaffs_Spare spare;
3982
3983         yaffs_ReadChunkFromNAND(dev,blk * dev->nChunksPerBlock,NULL,&spare,1);
3984 #if 1
3985         if(yaffs_CountBits(spare.blockStatus) < 7)
3986         {
3987                 return 1;
3988         }
3989 #else
3990         if(spare.blockStatus != 0xFF)
3991         {
3992                 return 1;
3993         }
3994 #endif
3995         yaffs_ReadChunkFromNAND(dev,blk * dev->nChunksPerBlock + 1,NULL,&spare,1);
3996
3997 #if 1
3998         if(yaffs_CountBits(spare.blockStatus) < 7)
3999         {
4000                 return 1;
4001         }
4002 #else
4003         if(spare.blockStatus != 0xFF)
4004         {
4005                 return 1;
4006         }
4007 #endif
4008
4009         return 0;
4010
4011 }
4012
4013 static int yaffs_Scan(yaffs_Device *dev)
4014 {
4015         yaffs_Spare spare;
4016         yaffs_Tags tags;
4017         int blk;
4018         int chunk;
4019         int c;
4020         int deleted;
4021         yaffs_BlockState state;
4022         yaffs_Object *hardList = NULL;
4023         yaffs_Object *hl;
4024         yaffs_BlockInfo *bi;
4025
4026
4027         yaffs_ObjectHeader *oh;
4028         yaffs_Object *in;
4029         yaffs_Object *parent;
4030
4031         __u8 chunkData[YAFFS_BYTES_PER_CHUNK];
4032
4033
4034         // Scan all the blocks...
4035
4036         for(blk = dev->startBlock; blk <= dev->endBlock; blk++)
4037         {
4038                 deleted = 0;
4039                 bi = yaffs_GetBlockInfo(dev,blk);
4040                 yaffs_ClearChunkBits(dev,blk);
4041                 bi->pagesInUse = 0;
4042                 bi->softDeletions = 0;
4043                 state = YAFFS_BLOCK_STATE_SCANNING;
4044
4045
4046                 if(yaffs_IsBlockBad(dev,blk))
4047                 {
4048                         state = YAFFS_BLOCK_STATE_DEAD;
4049                         T(YAFFS_TRACE_BAD_BLOCKS,(TSTR("block %d is bad" TENDSTR),blk));
4050                 }
4051
4052                 // Read each chunk in the block.
4053
4054                 for(c = 0; c < dev->nChunksPerBlock &&
4055                                    state == YAFFS_BLOCK_STATE_SCANNING; c++)
4056                 {
4057                         // Read the spare area and decide what to do
4058                         chunk = blk * dev->nChunksPerBlock + c;
4059
4060                         yaffs_ReadChunkFromNAND(dev,chunk,NULL,&spare,1);
4061
4062
4063                         // This block looks ok, now what's in this chunk?
4064                         yaffs_GetTagsFromSpare(dev,&spare,&tags);
4065
4066                         if(yaffs_CountBits(spare.pageStatus) < 6)
4067                         {
4068                                 // A deleted chunk
4069                                 deleted++;
4070                                 dev->nFreeChunks ++;
4071                                 //T((" %d %d deleted\n",blk,c));
4072                         }
4073                         else if(tags.objectId == YAFFS_UNUSED_OBJECT_ID)
4074                         {
4075                                 // An unassigned chunk in the block
4076                                 // This means that either the block is empty or
4077                                 // this is the one being allocated from
4078
4079                                 if(c == 0)
4080                                 {
4081                                         // the block is unused
4082                                         state = YAFFS_BLOCK_STATE_EMPTY;
4083                                         dev->nErasedBlocks++;
4084                                 }
4085                                 else
4086                                 {
4087                                         // this is the block being allocated from
4088                                         T(YAFFS_TRACE_SCAN,(TSTR(" Allocating from %d %d" TENDSTR),blk,c));
4089                                         state = YAFFS_BLOCK_STATE_ALLOCATING;
4090                                         dev->allocationBlock = blk;
4091                                         dev->allocationPage = c;
4092                                 }
4093
4094                                 dev->nFreeChunks += (dev->nChunksPerBlock - c);
4095                         }
4096                         else if(tags.chunkId > 0)
4097                         {
4098                                 int endpos;
4099                                 // A data chunk.
4100                                 yaffs_SetChunkBit(dev,blk,c);
4101                                 bi->pagesInUse++;
4102
4103                                 in = yaffs_FindOrCreateObjectByNumber(dev,tags.objectId,YAFFS_OBJECT_TYPE_FILE);
4104                                 // PutChunkIntoFIle checks for a clash (two data chunks with
4105                                 // the same chunkId).
4106                                 yaffs_PutChunkIntoFile(in,tags.chunkId,chunk,1);
4107                                 endpos = (tags.chunkId - 1)* YAFFS_BYTES_PER_CHUNK + tags.byteCount;
4108                                 if(in->variant.fileVariant.scannedFileSize <endpos)
4109                                 {
4110                                         in->variant.fileVariant.scannedFileSize = endpos;
4111 #ifndef CONFIG_YAFFS_USE_HEADER_FILE_SIZE
4112                                                 in->variant.fileVariant.fileSize =
4113                                                         in->variant.fileVariant.scannedFileSize;
4114 #endif
4115
4116                                 }
4117                                 //T((" %d %d data %d %d\n",blk,c,tags.objectId,tags.chunkId));
4118                         }
4119                         else
4120                         {
4121                                 // chunkId == 0, so it is an ObjectHeader.
4122                                 // Thus, we read in the object header and make the object
4123                                 yaffs_SetChunkBit(dev,blk,c);
4124                                 bi->pagesInUse++;
4125
4126                                 yaffs_ReadChunkFromNAND(dev,chunk,chunkData,NULL,1);
4127
4128                                 oh = (yaffs_ObjectHeader *)chunkData;
4129
4130                                 in = yaffs_FindOrCreateObjectByNumber(dev,tags.objectId,oh->type);
4131
4132                                 if(in->valid)
4133                                 {
4134                                         // We have already filled this one. We have a duplicate and need to resolve it.
4135
4136                                         unsigned existingSerial = in->serial;
4137                                         unsigned newSerial = tags.serialNumber;
4138
4139                                         if(((existingSerial+1) & 3) == newSerial)
4140                                         {
4141                                                 // Use new one - destroy the exisiting one
4142                                                 yaffs_DeleteChunk(dev,in->chunkId,1);
4143                                                 in->valid = 0;
4144                                         }
4145                                         else
4146                                         {
4147                                                 // Use existing - destroy this one.
4148                                                 yaffs_DeleteChunk(dev,chunk,1);
4149                                         }
4150                                 }
4151
4152                                 if(!in->valid &&
4153                                    (tags.objectId == YAFFS_OBJECTID_ROOT ||
4154                                     tags.objectId == YAFFS_OBJECTID_LOSTNFOUND))
4155                                 {
4156                                         // We only load some info, don't fiddle with directory structure
4157                                         in->valid = 1;
4158                                         in->variantType = oh->type;
4159
4160                                         in->st_mode  = oh->st_mode;
4161 #ifdef CONFIG_YAFFS_WINCE
4162                                         in->win_atime[0] = oh->win_atime[0];
4163                                         in->win_ctime[0] = oh->win_ctime[0];
4164                                         in->win_mtime[0] = oh->win_mtime[0];
4165                                         in->win_atime[1] = oh->win_atime[1];
4166                                         in->win_ctime[1] = oh->win_ctime[1];
4167                                         in->win_mtime[1] = oh->win_mtime[1];
4168 #else
4169                                         in->st_uid   = oh->st_uid;
4170                                         in->st_gid   = oh->st_gid;
4171                                         in->st_atime = oh->st_atime;
4172                                         in->st_mtime = oh->st_mtime;
4173                                         in->st_ctime = oh->st_ctime;
4174                                         in->st_rdev = oh->st_rdev;
4175 #endif
4176                                         in->chunkId  = chunk;
4177
4178                                 }
4179                                 else if(!in->valid)
4180                                 {
4181                                         // we need to load this info
4182
4183                                         in->valid = 1;
4184                                         in->variantType = oh->type;
4185
4186                                         in->st_mode  = oh->st_mode;
4187 #ifdef CONFIG_YAFFS_WINCE
4188                                         in->win_atime[0] = oh->win_atime[0];
4189                                         in->win_ctime[0] = oh->win_ctime[0];
4190                                         in->win_mtime[0] = oh->win_mtime[0];
4191                                         in->win_atime[1] = oh->win_atime[1];
4192                                         in->win_ctime[1] = oh->win_ctime[1];
4193                                         in->win_mtime[1] = oh->win_mtime[1];
4194 #else
4195                                         in->st_uid   = oh->st_uid;
4196                                         in->st_gid   = oh->st_gid;
4197                                         in->st_atime = oh->st_atime;
4198                                         in->st_mtime = oh->st_mtime;
4199                                         in->st_ctime = oh->st_ctime;
4200                                         in->st_rdev = oh->st_rdev;
4201 #endif
4202                                         in->chunkId  = chunk;
4203
4204                                         yaffs_SetObjectName(in,oh->name);
4205                                         in->dirty = 0;
4206
4207                                         // directory stuff...
4208                                         // hook up to parent
4209
4210                                         parent = yaffs_FindOrCreateObjectByNumber(dev,oh->parentObjectId,YAFFS_OBJECT_TYPE_DIRECTORY);
4211                                         if(parent->variantType == YAFFS_OBJECT_TYPE_UNKNOWN)
4212                                         {
4213                                                 // Set up as a directory
4214                                                 parent->variantType = YAFFS_OBJECT_TYPE_DIRECTORY;
4215                                                 INIT_LIST_HEAD(&parent->variant.directoryVariant.children);
4216                                         }
4217                                         else if(parent->variantType != YAFFS_OBJECT_TYPE_DIRECTORY)
4218                                         {
4219                                                 // Hoosterman, another problem....
4220                                                 // We're trying to use a non-directory as a directory
4221
4222                                                 T(YAFFS_TRACE_ERROR, (TSTR("yaffs tragedy: attempting to use non-directory as a directory in scan. Put in lost+found." TENDSTR)));
4223                                                 parent = dev->lostNFoundDir;
4224
4225                                         }
4226
4227                                         yaffs_AddObjectToDirectory(parent,in);
4228                                         if(parent == dev->unlinkedDir)
4229                                         {
4230                                                 in->deleted = 1; // If it is unlinked at start up then it wants deleting
4231                                                 dev->nDeletedFiles++;
4232                                         }
4233
4234                                         // Note re hardlinks.
4235                                         // Since we might scan a hardlink before its equivalent object is scanned
4236                                         // we put them all in a list.
4237                                         // After scanning is complete, we should have all the objects, so we run through this
4238                                         // list and fix up all the chains.
4239
4240                                         switch(in->variantType)
4241                                         {
4242                                                 case YAFFS_OBJECT_TYPE_UNKNOWN:         // Todo got a problem
4243                                                         break;
4244                                                 case YAFFS_OBJECT_TYPE_FILE:
4245 #ifdef CONFIG_YAFFS_USE_HEADER_FILE_SIZE
4246                                                         in->variant.fileVariant.fileSize = oh->fileSize;
4247 #endif
4248                                                         break;
4249                                                 case YAFFS_OBJECT_TYPE_HARDLINK:
4250                                                         in->variant.hardLinkVariant.equivalentObjectId = oh->equivalentObjectId;
4251                                                         in->hardLinks.next = (struct list_head *)hardList;
4252                                                         hardList = in;
4253                                                         break;
4254                                                 case YAFFS_OBJECT_TYPE_DIRECTORY:       // Do nothing
4255                                                         break;
4256                                                 case YAFFS_OBJECT_TYPE_SPECIAL: // Do nothing
4257                                                         break;
4258                                                 case YAFFS_OBJECT_TYPE_SYMLINK:         // Do nothing
4259                                                         in->variant.symLinkVariant.alias = yaffs_CloneString(oh->alias);
4260                                                         break;
4261                                         }
4262                                         //T((" %d %d header %d \"%s\" type %d\n",blk,c,tags.objectId,oh->name,in->variantType));
4263                                 }
4264                         }
4265                 }
4266
4267                 if(state == YAFFS_BLOCK_STATE_SCANNING)
4268                 {
4269                         // If we got this far while scanning, then the block is fully allocated.
4270                         state = YAFFS_BLOCK_STATE_FULL;
4271                 }
4272
4273                 bi->blockState = state;
4274
4275                 // Now let's see if it was dirty
4276                 if(     bi->pagesInUse == 0 &&
4277                 bi->blockState == YAFFS_BLOCK_STATE_FULL)
4278             {
4279                 yaffs_BlockBecameDirty(dev,blk);
4280             }
4281
4282         }
4283
4284         // Fix up the hard link chains.
4285         // We should now have scanned all the objects, now it's time to add these
4286         // hardlinks.
4287         while(hardList)
4288         {
4289                 hl = hardList;
4290                 hardList = (yaffs_Object *)(hardList->hardLinks.next);
4291
4292                 in = yaffs_FindObjectByNumber(dev,hl->variant.hardLinkVariant.equivalentObjectId);
4293
4294                 if(in)
4295                 {
4296                         // Add the hardlink pointers
4297                         hl->variant.hardLinkVariant.equivalentObject=in;
4298                         list_add(&hl->hardLinks,&in->hardLinks);
4299                 }
4300                 else
4301                 {
4302                         //Todo Need to report/handle this better.
4303                         // Got a problem... hardlink to a non-existant object
4304                         hl->variant.hardLinkVariant.equivalentObject=NULL;
4305                         INIT_LIST_HEAD(&hl->hardLinks);
4306
4307                 }
4308
4309         }
4310
4311         {
4312                 struct list_head *i;
4313                 struct list_head *n;
4314
4315                 yaffs_Object *l;
4316                 // Soft delete all the unlinked files
4317                 list_for_each_safe(i,n,&dev->unlinkedDir->variant.directoryVariant.children)
4318                 {
4319                         if(i)
4320                         {
4321                                 l = list_entry(i, yaffs_Object,siblings);
4322                                 if(l->deleted)
4323                                 {
4324                                         yaffs_SoftDeleteFile(l);
4325                                 }
4326                         }
4327                 }
4328         }
4329
4330
4331         return YAFFS_OK;
4332 }
4333
4334
4335 ////////////////////////// Directory Functions /////////////////////////
4336
4337
4338 static void yaffs_AddObjectToDirectory(yaffs_Object *directory, yaffs_Object *obj)
4339 {
4340
4341         if(obj->siblings.prev == NULL)
4342         {
4343                 // Not initialised
4344                 INIT_LIST_HEAD(&obj->siblings);
4345
4346         }
4347         else if(!list_empty(&obj->siblings))
4348         {
4349                 // If it is holed up somewhere else, un hook it
4350                 list_del_init(&obj->siblings);
4351         }
4352         // Now add it
4353         list_add(&obj->siblings,&directory->variant.directoryVariant.children);
4354         obj->parent = directory;
4355
4356         if(directory == obj->myDev->unlinkedDir)
4357         {
4358                 obj->unlinked = 1;
4359                 obj->myDev->nUnlinkedFiles++;
4360                 obj->renameAllowed = 0;
4361         }
4362 }
4363
4364 static void yaffs_RemoveObjectFromDirectory(yaffs_Object *obj)
4365 {
4366         list_del_init(&obj->siblings);
4367         obj->parent = NULL;
4368 }
4369
4370 yaffs_Object *yaffs_FindObjectByName(yaffs_Object *directory,const char *name)
4371 {
4372         int sum;
4373
4374         struct list_head *i;
4375         char buffer[YAFFS_MAX_NAME_LENGTH+1];
4376
4377         yaffs_Object *l;
4378
4379         sum = yaffs_CalcNameSum(name);
4380
4381         list_for_each(i,&directory->variant.directoryVariant.children)
4382         {
4383                 if(i)
4384                 {
4385                         l = list_entry(i, yaffs_Object,siblings);
4386
4387                         // Special case for lost-n-found
4388                         if(l->objectId == YAFFS_OBJECTID_LOSTNFOUND)
4389                         {
4390                                 if(yaffs_strcmp(name,YAFFS_LOSTNFOUND_NAME) == 0)
4391                                 {
4392                                         return l;
4393                                 }
4394                         }
4395                         else if(yaffs_SumCompare(l->sum, sum))
4396                         {
4397                                 // Do a real check
4398                                 yaffs_GetObjectName(l,buffer,YAFFS_MAX_NAME_LENGTH);
4399                                 if(yaffs_strcmp(name,buffer) == 0)
4400                                 {
4401                                         return l;
4402                                 }
4403
4404                         }
4405                 }
4406         }
4407
4408         return NULL;
4409 }
4410
4411
4412 int yaffs_ApplyToDirectoryChildren(yaffs_Object *theDir,int (*fn)(yaffs_Object *))
4413 {
4414         struct list_head *i;
4415         yaffs_Object *l;
4416
4417
4418         list_for_each(i,&theDir->variant.directoryVariant.children)
4419         {
4420                 if(i)
4421                 {
4422                         l = list_entry(i, yaffs_Object,siblings);
4423                         if(l && !fn(l))
4424                         {
4425                                 return YAFFS_FAIL;
4426                         }
4427                 }
4428         }
4429
4430         return YAFFS_OK;
4431
4432 }
4433
4434
4435 // GetEquivalentObject dereferences any hard links to get to the
4436 // actual object.
4437
4438 yaffs_Object *yaffs_GetEquivalentObject(yaffs_Object *obj)
4439 {
4440         if(obj && obj->variantType == YAFFS_OBJECT_TYPE_HARDLINK)
4441         {
4442                 // We want the object id of the equivalent object, not this one
4443                 obj = obj->variant.hardLinkVariant.equivalentObject;
4444         }
4445         return obj;
4446
4447 }
4448
4449 int yaffs_GetObjectName(yaffs_Object *obj,char *name,int buffSize)
4450 {
4451         memset(name,0,buffSize);
4452
4453         if(obj->objectId == YAFFS_OBJECTID_LOSTNFOUND)
4454         {
4455                 strncpy(name,YAFFS_LOSTNFOUND_NAME,buffSize - 1);
4456         }
4457         else if(obj->chunkId <= 0)
4458         {
4459                 char locName[20];
4460                 // make up a name
4461                 sprintf(locName,"%s%d",YAFFS_LOSTNFOUND_PREFIX,obj->objectId);
4462                 strncpy(name,locName,buffSize - 1);
4463
4464         }
4465 #ifdef CONFIG_YAFFS_SHORT_NAMES_IN_RAM
4466         else if(obj->shortName[0])
4467         {
4468                 strcpy(name,obj->shortName);
4469         }
4470 #endif
4471         else
4472         {
4473                 __u8 buffer[YAFFS_BYTES_PER_CHUNK];
4474                 yaffs_ObjectHeader *oh = (yaffs_ObjectHeader *)buffer;
4475
4476                 memset(buffer,0,YAFFS_BYTES_PER_CHUNK);
4477
4478                 if(obj->chunkId >= 0)
4479                 {
4480                         yaffs_ReadChunkFromNAND(obj->myDev,obj->chunkId,buffer,NULL,1);
4481                 }
4482                 strncpy(name,oh->name,buffSize - 1);
4483         }
4484
4485         return strlen(name);
4486 }
4487
4488 int yaffs_GetObjectFileLength(yaffs_Object *obj)
4489 {
4490
4491         // Dereference any hard linking
4492         obj = yaffs_GetEquivalentObject(obj);
4493
4494         if(obj->variantType == YAFFS_OBJECT_TYPE_FILE)
4495         {
4496                 return obj->variant.fileVariant.fileSize;
4497         }
4498         if(obj->variantType == YAFFS_OBJECT_TYPE_SYMLINK)
4499         {
4500                 return strlen(obj->variant.symLinkVariant.alias);
4501         }
4502         else
4503         {
4504                 // Only a directory should drop through to here
4505                 return YAFFS_BYTES_PER_CHUNK;
4506         }
4507 }
4508
4509 int yaffs_GetObjectLinkCount(yaffs_Object *obj)
4510 {
4511         int count = 0;
4512         struct list_head *i;
4513
4514         if(!obj->unlinked)
4515         {
4516                 count++;        // the object itself
4517         }
4518         list_for_each(i,&obj->hardLinks)
4519         {
4520                 count++;        // add the hard links;
4521         }
4522         return count;
4523
4524 }
4525
4526
4527 int yaffs_GetObjectInode(yaffs_Object *obj)
4528 {
4529         obj = yaffs_GetEquivalentObject(obj);
4530
4531         return obj->objectId;
4532 }
4533
4534 unsigned yaffs_GetObjectType(yaffs_Object *obj)
4535 {
4536         obj = yaffs_GetEquivalentObject(obj);
4537
4538         switch(obj->variantType)
4539         {
4540                 case YAFFS_OBJECT_TYPE_FILE:            return DT_REG; break;
4541                 case YAFFS_OBJECT_TYPE_DIRECTORY:       return DT_DIR; break;
4542                 case YAFFS_OBJECT_TYPE_SYMLINK:         return DT_LNK; break;
4543                 case YAFFS_OBJECT_TYPE_HARDLINK:        return DT_REG; break;
4544                 case YAFFS_OBJECT_TYPE_SPECIAL:
4545                         if(S_ISFIFO(obj->st_mode)) return DT_FIFO;
4546                         if(S_ISCHR(obj->st_mode)) return DT_CHR;
4547                         if(S_ISBLK(obj->st_mode)) return DT_BLK;
4548                         if(S_ISSOCK(obj->st_mode)) return DT_SOCK;
4549                 default: return DT_REG; break;
4550         }
4551 }
4552
4553 char *yaffs_GetSymlinkAlias(yaffs_Object *obj)
4554 {
4555         obj = yaffs_GetEquivalentObject(obj);
4556         if(obj->variantType == YAFFS_OBJECT_TYPE_SYMLINK)
4557         {
4558                 return yaffs_CloneString(obj->variant.symLinkVariant.alias);
4559         }
4560         else
4561         {
4562                 return yaffs_CloneString("");
4563         }
4564 }
4565
4566 #ifndef CONFIG_YAFFS_WINCE
4567
4568 int yaffs_SetAttributes(yaffs_Object *obj, struct iattr *attr)
4569 {
4570         unsigned int valid = attr->ia_valid;
4571
4572         if(valid & ATTR_MODE) obj->st_mode = attr->ia_mode;
4573         if(valid & ATTR_UID) obj->st_uid = attr->ia_uid;
4574         if(valid & ATTR_GID) obj->st_gid = attr->ia_gid;
4575
4576         if(valid & ATTR_ATIME) obj->st_atime = Y_TIME_CONVERT(attr->ia_atime);
4577         if(valid & ATTR_CTIME) obj->st_ctime = Y_TIME_CONVERT(attr->ia_ctime);
4578         if(valid & ATTR_MTIME) obj->st_mtime = Y_TIME_CONVERT(attr->ia_mtime);
4579
4580
4581         if(valid & ATTR_SIZE) yaffs_ResizeFile(obj,attr->ia_size);
4582
4583         yaffs_UpdateObjectHeader(obj,NULL,1);
4584
4585         return YAFFS_OK;
4586
4587 }
4588
4589 int yaffs_GetAttributes(yaffs_Object *obj, struct iattr *attr)
4590 {
4591         unsigned int valid = 0;
4592
4593         attr->ia_mode = obj->st_mode;   valid |= ATTR_MODE;
4594         attr->ia_uid = obj->st_uid;             valid |= ATTR_UID;
4595         attr->ia_gid = obj->st_gid;             valid |= ATTR_GID;
4596
4597
4598         Y_TIME_CONVERT(attr->ia_atime) = obj->st_atime; valid |= ATTR_ATIME;
4599         Y_TIME_CONVERT(attr->ia_ctime) = obj->st_ctime; valid |= ATTR_CTIME;
4600         Y_TIME_CONVERT(attr->ia_mtime) = obj->st_mtime; valid |= ATTR_MTIME;
4601
4602         attr->ia_size = yaffs_GetFileSize(obj); valid |= ATTR_SIZE;
4603
4604         attr->ia_valid = valid;
4605
4606         return YAFFS_OK;
4607
4608 }
4609
4610 #endif
4611
4612 int yaffs_DumpObject(yaffs_Object *obj)
4613 {
4614 //      __u8 buffer[YAFFS_BYTES_PER_CHUNK];
4615         char name[257];
4616 //      yaffs_ObjectHeader *oh = (yaffs_ObjectHeader *)buffer;
4617
4618 //      memset(buffer,0,YAFFS_BYTES_PER_CHUNK);
4619
4620 //      if(obj->chunkId >= 0)
4621 //      {
4622 //              yaffs_ReadChunkFromNAND(obj->myDev,obj->chunkId,buffer,NULL);
4623 //      }
4624
4625         yaffs_GetObjectName(obj,name,256);
4626
4627         T(YAFFS_TRACE_ALWAYS,(TSTR("Object %d, inode %d \"%s\"\n dirty %d valid %d serial %d sum %d chunk %d type %d size %d\n" TENDSTR),
4628                         obj->objectId,yaffs_GetObjectInode(obj), name, obj->dirty, obj->valid, obj->serial,
4629                         obj->sum, obj->chunkId, yaffs_GetObjectType(obj), yaffs_GetObjectFileLength(obj)));
4630
4631 #if 0
4632         YPRINTF(("Object %d \"%s\"\n dirty %d valid %d serial %d sum %d chunk %d\n",
4633                         obj->objectId, oh->name, obj->dirty, obj->valid, obj->serial,
4634                         obj->sum, obj->chunkId));
4635                 switch(obj->variantType)
4636         {
4637                 case YAFFS_OBJECT_TYPE_FILE:
4638                         YPRINTF((" FILE length %d\n",obj->variant.fileVariant.fileSize));
4639                         break;
4640                 case YAFFS_OBJECT_TYPE_DIRECTORY:
4641                         YPRINTF((" DIRECTORY\n"));
4642                         break;
4643                 case YAFFS_OBJECT_TYPE_HARDLINK: //todo
4644                 case YAFFS_OBJECT_TYPE_SYMLINK:
4645                 case YAFFS_OBJECT_TYPE_UNKNOWN:
4646                 default:
4647         }
4648 #endif
4649
4650         return YAFFS_OK;
4651 }
4652
4653
4654 ///////////////////////// Initialisation code ///////////////////////////
4655
4656
4657
4658 int yaffs_GutsInitialise(yaffs_Device *dev)
4659 {
4660         unsigned x;
4661         int bits;
4662         int extraBits;
4663         int nBlocks;
4664
4665         if(     dev->nBytesPerChunk != YAFFS_BYTES_PER_CHUNK ||
4666                 dev->nChunksPerBlock < 2 ||
4667                 dev->nReservedBlocks < 2 ||
4668                 dev->startBlock <= 0 ||
4669                 dev->endBlock <= 0 ||
4670                 dev->endBlock <= (dev->startBlock + dev->nReservedBlocks)
4671           )
4672         {
4673                 //these parameters must be set before stating yaffs
4674                 // Other parameters startBlock,
4675                 return YAFFS_FAIL;
4676         }
4677
4678
4679
4680         if(!yaffs_CheckStructures())
4681         {
4682                 T(YAFFS_TRACE_ALWAYS,(TSTR("yaffs_CheckStructures failed\n" TENDSTR)));
4683                 return YAFFS_FAIL;
4684         }
4685
4686         if(dev->isMounted)
4687         {
4688                 T(YAFFS_TRACE_ALWAYS,(TSTR("yaffs: device already mounted\n" TENDSTR)));
4689                 return YAFFS_FAIL;
4690         }
4691
4692         dev->isMounted = 1;
4693
4694         if(dev->startBlock <= 0 ||
4695            (dev->endBlock - dev->startBlock) < 10)
4696         {
4697                 T(YAFFS_TRACE_ALWAYS,(TSTR("startBlock %d or endBlock %d invalid\n" TENDSTR),
4698                                 dev->startBlock, dev->endBlock));
4699                 return YAFFS_FAIL;
4700         }
4701
4702         nBlocks = dev->endBlock - dev->startBlock + 1;
4703
4704
4705
4706         // OK now calculate a few things for the device
4707         // Calculate chunkGroupBits.
4708         // We need to find the next power of 2 > than endBlock
4709
4710         x = dev->nChunksPerBlock * (dev->endBlock+1);
4711
4712         for(bits = extraBits = 0; x > 1; bits++)
4713         {
4714                 if(x & 1) extraBits++;
4715                 x >>= 1;
4716         }
4717
4718         if(extraBits > 0) bits++;
4719
4720
4721         // Level0 Tnodes are 16 bits, so if the bitwidth of the
4722         // chunk range we're using is greater than 16 we need
4723         // to figure out chunk shift and chunkGroupSize
4724         if(bits <= 16)
4725         {
4726                 dev->chunkGroupBits = 0;
4727         }
4728         else
4729         {
4730                 dev->chunkGroupBits = bits - 16;
4731         }
4732
4733         dev->chunkGroupSize = 1 << dev->chunkGroupBits;
4734
4735         if(dev->nChunksPerBlock < dev->chunkGroupSize)
4736         {
4737                 // We have a problem because the soft delete won't work if
4738                 // the chunk group size > chunks per block.
4739                 // This can be remedied by using larger "virtual blocks".
4740
4741                 return YAFFS_FAIL;
4742         }
4743
4744
4745
4746
4747         // More device initialisation
4748         dev->garbageCollections = 0;
4749         dev->passiveGarbageCollections = 0;
4750         dev->currentDirtyChecker = 0;
4751         dev->bufferedBlock = -1;
4752         dev->doingBufferedBlockRewrite = 0;
4753         dev->nDeletedFiles = 0;
4754         dev->nBackgroundDeletions=0;
4755         dev->nUnlinkedFiles = 0;
4756         dev->eccFixed=0;
4757         dev->eccUnfixed=0;
4758         dev->tagsEccFixed=0;
4759         dev->tagsEccUnfixed=0;
4760
4761         dev->localBuffer = YMALLOC(dev->nBytesPerChunk);
4762
4763
4764
4765
4766         yaffs_InitialiseBlocks(dev,nBlocks);
4767
4768         yaffs_InitialiseTnodes(dev);
4769
4770         yaffs_InitialiseObjects(dev);
4771
4772         if(dev->nShortOpCaches > 0)
4773         {
4774                 int i;
4775
4776                 if(dev->nShortOpCaches >  YAFFS_MAX_SHORT_OP_CACHES)
4777                 {
4778                         dev->nShortOpCaches = YAFFS_MAX_SHORT_OP_CACHES;
4779                 }
4780
4781                 dev->srCache = YMALLOC( dev->nShortOpCaches * sizeof(yaffs_ChunkCache));
4782
4783                 for(i=0; i < dev->nShortOpCaches; i++)
4784                 {
4785                         dev->srCache[i].object = NULL;
4786                         dev->srCache[i].lastUse = 0;
4787                         dev->srCache[i].dirty = 0;
4788                 }
4789                 dev->srLastUse = 0;
4790         }
4791
4792         dev->cacheHits = 0;
4793
4794
4795         // Initialise the unlinked, root and lost and found directories
4796         dev->lostNFoundDir = dev->rootDir = dev->unlinkedDir = NULL;
4797
4798         dev->unlinkedDir = yaffs_CreateFakeDirectory(dev,YAFFS_OBJECTID_UNLINKED, S_IFDIR);
4799
4800         dev->rootDir = yaffs_CreateFakeDirectory(dev,YAFFS_OBJECTID_ROOT,YAFFS_ROOT_MODE | S_IFDIR);
4801         dev->lostNFoundDir = yaffs_CreateFakeDirectory(dev,YAFFS_OBJECTID_LOSTNFOUND,YAFFS_LOSTNFOUND_MODE | S_IFDIR);
4802         yaffs_AddObjectToDirectory(dev->rootDir,dev->lostNFoundDir);
4803
4804
4805         // Now scan the flash.
4806         yaffs_Scan(dev);
4807
4808         // Zero out stats
4809         dev->nPageReads = 0;
4810     dev->nPageWrites =  0;
4811         dev->nBlockErasures = 0;
4812         dev->nGCCopies = 0;
4813         dev->nRetriedWrites = 0;
4814         dev->nRetiredBlocks = 0;
4815
4816
4817         return YAFFS_OK;
4818
4819 }
4820
4821 void yaffs_Deinitialise(yaffs_Device *dev)
4822 {
4823         if(dev->isMounted)
4824         {
4825
4826                 yaffs_DeinitialiseBlocks(dev);
4827                 yaffs_DeinitialiseTnodes(dev);
4828                 yaffs_DeinitialiseObjects(dev);
4829                 if(dev->nShortOpCaches > 0)
4830                         YFREE(dev->srCache);
4831                 YFREE(dev->localBuffer);
4832         }
4833
4834 }
4835
4836 #if 0
4837
4838 int  yaffs_GetNumberOfFreeChunks(yaffs_Device *dev)
4839 {
4840         int nFree = dev->nFreeChunks - (dev->nChunksPerBlock * YAFFS_RESERVED_BLOCKS);
4841
4842         struct list_head *i;
4843         yaffs_Object *l;
4844
4845
4846         // To the free chunks add the chunks that are in the deleted unlinked files.
4847         list_for_each(i,&dev->unlinkedDir->variant.directoryVariant.children)
4848         {
4849                 l = list_entry(i, yaffs_Object,siblings);
4850                 if(l->deleted)
4851                 {
4852                         nFree++;
4853                         nFree += l->nDataChunks;
4854                 }
4855         }
4856
4857
4858         // printf("___________ nFreeChunks is %d nFree is %d\n",dev->nFreeChunks,nFree);
4859
4860         if(nFree < 0) nFree = 0;
4861
4862         return nFree;
4863
4864 }
4865
4866 #endif
4867
4868 int  yaffs_GetNumberOfFreeChunks(yaffs_Device *dev)
4869 {
4870         int nFree;
4871         int pending;
4872         int b;
4873         int nDirtyCacheChunks=0;
4874
4875         yaffs_BlockInfo *blk;
4876
4877         struct list_head *i;
4878         yaffs_Object *l;
4879
4880         for(nFree = 0, b = dev->startBlock; b <= dev->endBlock; b++)
4881         {
4882                 blk = yaffs_GetBlockInfo(dev,b);
4883
4884                 switch(blk->blockState)
4885                 {
4886                         case YAFFS_BLOCK_STATE_EMPTY:
4887                         case YAFFS_BLOCK_STATE_ALLOCATING:
4888                         case YAFFS_BLOCK_STATE_FULL: nFree += (dev->nChunksPerBlock - blk->pagesInUse); break;
4889                         default: break;
4890                 }
4891         }
4892
4893
4894         pending = 0;
4895
4896         // To the free chunks add the chunks that are in the deleted unlinked files.
4897         list_for_each(i,&dev->unlinkedDir->variant.directoryVariant.children)
4898         {
4899                 if(i)
4900                 {
4901                         l = list_entry(i, yaffs_Object,siblings);
4902                         if(l->deleted)
4903                         {
4904                                 pending++;
4905                                 pending += l->nDataChunks;
4906                         }
4907                 }
4908         }
4909
4910
4911
4912         //printf("___________ really free is %d, pending %d, nFree is %d\n",nFree,pending, nFree+pending);
4913
4914         if(nFree != dev->nFreeChunks)
4915         {
4916         //      printf("___________Different! really free is %d, nFreeChunks %d\n",nFree dev->nFreeChunks);
4917         }
4918
4919         nFree += pending;
4920
4921         // Now count the number of dirty chunks in the cache and subtract those
4922
4923         {
4924                 int i;
4925                 for(i = 0; i < dev->nShortOpCaches; i++)
4926                 {
4927                         if(dev->srCache[i].dirty) nDirtyCacheChunks++;
4928                 }
4929         }
4930
4931         nFree -= nDirtyCacheChunks;
4932
4933         nFree -= ((dev->nReservedBlocks + 1) * dev->nChunksPerBlock);
4934
4935         if(nFree < 0) nFree = 0;
4936
4937         return nFree;
4938
4939 }
4940
4941
4942
4943 /////////////////// YAFFS test code //////////////////////////////////
4944
4945 #define yaffs_CheckStruct(structure,syze, name) \
4946            if(sizeof(structure) != syze) \
4947                { \
4948                  T(YAFFS_TRACE_ALWAYS,(TSTR("%s should be %d but is %d\n" TENDSTR),name,syze,sizeof(structure))); \
4949                  return YAFFS_FAIL; \
4950                    }
4951
4952
4953 static int yaffs_CheckStructures(void)
4954 {
4955         yaffs_CheckStruct(yaffs_Tags,8,"yaffs_Tags")
4956         yaffs_CheckStruct(yaffs_TagsUnion,8,"yaffs_TagsUnion")
4957         yaffs_CheckStruct(yaffs_Spare,16,"yaffs_Spare")
4958 #ifndef CONFIG_YAFFS_TNODE_LIST_DEBUG
4959         yaffs_CheckStruct(yaffs_Tnode,2* YAFFS_NTNODES_LEVEL0,"yaffs_Tnode")
4960 #endif
4961         yaffs_CheckStruct(yaffs_ObjectHeader,512,"yaffs_ObjectHeader")
4962
4963
4964         return YAFFS_OK;
4965 }
4966
4967 #if 0
4968 void yaffs_GutsTest(yaffs_Device *dev)
4969 {
4970
4971         if(yaffs_CheckStructures() != YAFFS_OK)
4972         {
4973                 T(YAFFS_TRACE_ALWAYS,(TSTR("One or more structures malformed-- aborting\n" TENDSTR)));
4974                 return;
4975         }
4976
4977         yaffs_TnodeTest(dev);
4978         yaffs_ObjectTest(dev);
4979 }
4980 #endif
4981
4982
4983
4984
4985
4986