target/linux/generic/files/fs/yaffs2/yaffs_guts.h

   1 /*
   2  * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
   3  *
   4  * Copyright (C) 2002-2007 Aleph One Ltd.
   5  *   for Toby Churchill Ltd and Brightstar Engineering
   6  *
   7  * Created by Charles Manning <charles@aleph1.co.uk>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU Lesser General Public License version 2.1 as
  11  * published by the Free Software Foundation.
  12  *
  13  * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
  14  */
  15
  16 #ifndef __YAFFS_GUTS_H__
  17 #define __YAFFS_GUTS_H__
  18
  19 #include "devextras.h"
  20 #include "yportenv.h"
  21
  22 #define YAFFS_OK        1
  23 #define YAFFS_FAIL  0
  24
  25 /* Give us a  Y=0x59,
  26  * Give us an A=0x41,
  27  * Give us an FF=0xFF
  28  * Give us an S=0x53
  29  * And what have we got...
  30  */
  31 #define YAFFS_MAGIC                     0x5941FF53
  32
  33 #define YAFFS_NTNODES_LEVEL0            16
  34 #define YAFFS_TNODES_LEVEL0_BITS        4
  35 #define YAFFS_TNODES_LEVEL0_MASK        0xf
  36
  37 #define YAFFS_NTNODES_INTERNAL          (YAFFS_NTNODES_LEVEL0 / 2)
  38 #define YAFFS_TNODES_INTERNAL_BITS      (YAFFS_TNODES_LEVEL0_BITS - 1)
  39 #define YAFFS_TNODES_INTERNAL_MASK      0x7
  40 #define YAFFS_TNODES_MAX_LEVEL          6
  41
  42 #ifndef CONFIG_YAFFS_NO_YAFFS1
  43 #define YAFFS_BYTES_PER_SPARE           16
  44 #define YAFFS_BYTES_PER_CHUNK           512
  45 #define YAFFS_CHUNK_SIZE_SHIFT          9
  46 #define YAFFS_CHUNKS_PER_BLOCK          32
  47 #define YAFFS_BYTES_PER_BLOCK           (YAFFS_CHUNKS_PER_BLOCK*YAFFS_BYTES_PER_CHUNK)
  48 #endif
  49
  50 #define YAFFS_MIN_YAFFS2_CHUNK_SIZE     1024
  51 #define YAFFS_MIN_YAFFS2_SPARE_SIZE     32
  52
  53 #define YAFFS_MAX_CHUNK_ID              0x000FFFFF
  54
  55 #define YAFFS_UNUSED_OBJECT_ID          0x0003FFFF
  56
  57 #define YAFFS_ALLOCATION_NOBJECTS       100
  58 #define YAFFS_ALLOCATION_NTNODES        100
  59 #define YAFFS_ALLOCATION_NLINKS         100
  60
  61 #define YAFFS_NOBJECT_BUCKETS           256
  62
  63
  64 #define YAFFS_OBJECT_SPACE              0x40000
  65
  66 #define YAFFS_CHECKPOINT_VERSION        3
  67
  68 #ifdef CONFIG_YAFFS_UNICODE
  69 #define YAFFS_MAX_NAME_LENGTH           127
  70 #define YAFFS_MAX_ALIAS_LENGTH          79
  71 #else
  72 #define YAFFS_MAX_NAME_LENGTH           255
  73 #define YAFFS_MAX_ALIAS_LENGTH          159
  74 #endif
  75
  76 #define YAFFS_SHORT_NAME_LENGTH         15
  77
  78 /* Some special object ids for pseudo objects */
  79 #define YAFFS_OBJECTID_ROOT             1
  80 #define YAFFS_OBJECTID_LOSTNFOUND       2
  81 #define YAFFS_OBJECTID_UNLINKED         3
  82 #define YAFFS_OBJECTID_DELETED          4
  83
  84 /* Sseudo object ids for checkpointing */
  85 #define YAFFS_OBJECTID_SB_HEADER        0x10
  86 #define YAFFS_OBJECTID_CHECKPOINT_DATA  0x20
  87 #define YAFFS_SEQUENCE_CHECKPOINT_DATA  0x21
  88
  89 /* */
  90
  91 #define YAFFS_MAX_SHORT_OP_CACHES       20
  92
  93 #define YAFFS_N_TEMP_BUFFERS            4
  94
  95 /* We limit the number attempts at sucessfully saving a chunk of data.
  96  * Small-page devices have 32 pages per block; large-page devices have 64.
  97  * Default to something in the order of 5 to 10 blocks worth of chunks.
  98  */
  99 #define YAFFS_WR_ATTEMPTS               (5*64)
 100
 101 /* Sequence numbers are used in YAFFS2 to determine block allocation order.
 102  * The range is limited slightly to help distinguish bad numbers from good.
 103  * This also allows us to perhaps in the future use special numbers for
 104  * special purposes.
 105  * EFFFFF00 allows the allocation of 8 blocks per second (~1Mbytes) for 15 years,
 106  * and is a larger number than the lifetime of a 2GB device.
 107  */
 108 #define YAFFS_LOWEST_SEQUENCE_NUMBER    0x00001000
 109 #define YAFFS_HIGHEST_SEQUENCE_NUMBER   0xEFFFFF00
 110
 111 /* ChunkCache is used for short read/write operations.*/
 112 typedef struct {
 113         struct yaffs_ObjectStruct *object;
 114         int chunkId;
 115         int lastUse;
 116         int dirty;
 117         int nBytes;             /* Only valid if the cache is dirty */
 118         int locked;             /* Can't push out or flush while locked. */
 119 #ifdef CONFIG_YAFFS_YAFFS2
 120         __u8 *data;
 121 #else
 122         __u8 data[YAFFS_BYTES_PER_CHUNK];
 123 #endif
 124 } yaffs_ChunkCache;
 125
 126
 127
 128 /* Tags structures in RAM
 129  * NB This uses bitfield. Bitfields should not straddle a u32 boundary otherwise
 130  * the structure size will get blown out.
 131  */
 132
 133 #ifndef CONFIG_YAFFS_NO_YAFFS1
 134 typedef struct {
 135         unsigned chunkId:20;
 136         unsigned serialNumber:2;
 137         unsigned byteCount:10;
 138         unsigned objectId:18;
 139         unsigned ecc:12;
 140         unsigned unusedStuff:2;
 141
 142 } yaffs_Tags;
 143
 144 typedef union {
 145         yaffs_Tags asTags;
 146         __u8 asBytes[8];
 147 } yaffs_TagsUnion;
 148
 149 #endif
 150
 151 /* Stuff used for extended tags in YAFFS2 */
 152
 153 typedef enum {
 154         YAFFS_ECC_RESULT_UNKNOWN,
 155         YAFFS_ECC_RESULT_NO_ERROR,
 156         YAFFS_ECC_RESULT_FIXED,
 157         YAFFS_ECC_RESULT_UNFIXED
 158 } yaffs_ECCResult;
 159
 160 typedef enum {
 161         YAFFS_OBJECT_TYPE_UNKNOWN,
 162         YAFFS_OBJECT_TYPE_FILE,
 163         YAFFS_OBJECT_TYPE_SYMLINK,
 164         YAFFS_OBJECT_TYPE_DIRECTORY,
 165         YAFFS_OBJECT_TYPE_HARDLINK,
 166         YAFFS_OBJECT_TYPE_SPECIAL
 167 } yaffs_ObjectType;
 168
 169 #define YAFFS_OBJECT_TYPE_MAX YAFFS_OBJECT_TYPE_SPECIAL
 170
 171 typedef struct {
 172
 173         unsigned validMarker0;
 174         unsigned chunkUsed;     /*  Status of the chunk: used or unused */
 175         unsigned objectId;      /* If 0 then this is not part of an object (unused) */
 176         unsigned chunkId;       /* If 0 then this is a header, else a data chunk */
 177         unsigned byteCount;     /* Only valid for data chunks */
 178
 179         /* The following stuff only has meaning when we read */
 180         yaffs_ECCResult eccResult;
 181         unsigned blockBad;
 182
 183         /* YAFFS 1 stuff */
 184         unsigned chunkDeleted;  /* The chunk is marked deleted */
 185         unsigned serialNumber;  /* Yaffs1 2-bit serial number */
 186
 187         /* YAFFS2 stuff */
 188         unsigned sequenceNumber;        /* The sequence number of this block */
 189
 190         /* Extra info if this is an object header (YAFFS2 only) */
 191
 192         unsigned extraHeaderInfoAvailable;      /* There is extra info available if this is not zero */
 193         unsigned extraParentObjectId;   /* The parent object */
 194         unsigned extraIsShrinkHeader;   /* Is it a shrink header? */
 195         unsigned extraShadows;          /* Does this shadow another object? */
 196
 197         yaffs_ObjectType extraObjectType;       /* What object type? */
 198
 199         unsigned extraFileLength;               /* Length if it is a file */
 200         unsigned extraEquivalentObjectId;       /* Equivalent object Id if it is a hard link */
 201
 202         unsigned validMarker1;
 203
 204 } yaffs_ExtendedTags;
 205
 206 /* Spare structure for YAFFS1 */
 207 typedef struct {
 208         __u8 tagByte0;
 209         __u8 tagByte1;
 210         __u8 tagByte2;
 211         __u8 tagByte3;
 212         __u8 pageStatus;        /* set to 0 to delete the chunk */
 213         __u8 blockStatus;
 214         __u8 tagByte4;
 215         __u8 tagByte5;
 216         __u8 ecc1[3];
 217         __u8 tagByte6;
 218         __u8 tagByte7;
 219         __u8 ecc2[3];
 220 } yaffs_Spare;
 221
 222 /*Special structure for passing through to mtd */
 223 struct yaffs_NANDSpare {
 224         yaffs_Spare spare;
 225         int eccres1;
 226         int eccres2;
 227 };
 228
 229 /* Block data in RAM */
 230
 231 typedef enum {
 232         YAFFS_BLOCK_STATE_UNKNOWN = 0,
 233
 234         YAFFS_BLOCK_STATE_SCANNING,
 235         YAFFS_BLOCK_STATE_NEEDS_SCANNING,
 236         /* The block might have something on it (ie it is allocating or full, perhaps empty)
 237          * but it needs to be scanned to determine its true state.
 238          * This state is only valid during yaffs_Scan.
 239          * NB We tolerate empty because the pre-scanner might be incapable of deciding
 240          * However, if this state is returned on a YAFFS2 device, then we expect a sequence number
 241          */
 242
 243         YAFFS_BLOCK_STATE_EMPTY,
 244         /* This block is empty */
 245
 246         YAFFS_BLOCK_STATE_ALLOCATING,
 247         /* This block is partially allocated.
 248          * At least one page holds valid data.
 249          * This is the one currently being used for page
 250          * allocation. Should never be more than one of these
 251          */
 252
 253         YAFFS_BLOCK_STATE_FULL,
 254         /* All the pages in this block have been allocated.
 255          */
 256
 257         YAFFS_BLOCK_STATE_DIRTY,
 258         /* All pages have been allocated and deleted.
 259          * Erase me, reuse me.
 260          */
 261
 262         YAFFS_BLOCK_STATE_CHECKPOINT,
 263         /* This block is assigned to holding checkpoint data.
 264          */
 265
 266         YAFFS_BLOCK_STATE_COLLECTING,
 267         /* This block is being garbage collected */
 268
 269         YAFFS_BLOCK_STATE_DEAD
 270         /* This block has failed and is not in use */
 271 } yaffs_BlockState;
 272
 273 #define YAFFS_NUMBER_OF_BLOCK_STATES (YAFFS_BLOCK_STATE_DEAD + 1)
 274
 275
 276 typedef struct {
 277
 278         int softDeletions:10;   /* number of soft deleted pages */
 279         int pagesInUse:10;      /* number of pages in use */
 280         yaffs_BlockState blockState:4;  /* One of the above block states */
 281         __u32 needsRetiring:1;  /* Data has failed on this block, need to get valid data off */
 282                                 /* and retire the block. */
 283         __u32 skipErasedCheck: 1; /* If this is set we can skip the erased check on this block */
 284         __u32 gcPrioritise: 1;  /* An ECC check or blank check has failed on this block.
 285                                    It should be prioritised for GC */
 286         __u32 chunkErrorStrikes:3; /* How many times we've had ecc etc failures on this block and tried to reuse it */
 287
 288 #ifdef CONFIG_YAFFS_YAFFS2
 289         __u32 hasShrinkHeader:1; /* This block has at least one shrink object header */
 290         __u32 sequenceNumber;    /* block sequence number for yaffs2 */
 291 #endif
 292
 293 } yaffs_BlockInfo;
 294
 295 /* -------------------------- Object structure -------------------------------*/
 296 /* This is the object structure as stored on NAND */
 297
 298 typedef struct {
 299         yaffs_ObjectType type;
 300
 301         /* Apply to everything  */
 302         int parentObjectId;
 303         __u16 sum__NoLongerUsed;        /* checksum of name. No longer used */
 304         YCHAR name[YAFFS_MAX_NAME_LENGTH + 1];
 305
 306         /* Thes following apply to directories, files, symlinks - not hard links */
 307         __u32 yst_mode;         /* protection */
 308
 309 #ifdef CONFIG_YAFFS_WINCE
 310         __u32 notForWinCE[5];
 311 #else
 312         __u32 yst_uid;
 313         __u32 yst_gid;
 314         __u32 yst_atime;
 315         __u32 yst_mtime;
 316         __u32 yst_ctime;
 317 #endif
 318
 319         /* File size  applies to files only */
 320         int fileSize;
 321
 322         /* Equivalent object id applies to hard links only. */
 323         int equivalentObjectId;
 324
 325         /* Alias is for symlinks only. */
 326         YCHAR alias[YAFFS_MAX_ALIAS_LENGTH + 1];
 327
 328         __u32 yst_rdev;         /* device stuff for block and char devices (major/min) */
 329
 330 #ifdef CONFIG_YAFFS_WINCE
 331         __u32 win_ctime[2];
 332         __u32 win_atime[2];
 333         __u32 win_mtime[2];
 334         __u32 roomToGrow[4];
 335 #else
 336         __u32 roomToGrow[10];
 337 #endif
 338
 339         int shadowsObject;      /* This object header shadows the specified object if > 0 */
 340
 341         /* isShrink applies to object headers written when we shrink the file (ie resize) */
 342         __u32 isShrink;
 343
 344 } yaffs_ObjectHeader;
 345
 346 /*--------------------------- Tnode -------------------------- */
 347
 348 union yaffs_Tnode_union {
 349 #ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
 350         union yaffs_Tnode_union *internal[YAFFS_NTNODES_INTERNAL + 1];
 351 #else
 352         union yaffs_Tnode_union *internal[YAFFS_NTNODES_INTERNAL];
 353 #endif
 354 /*      __u16 level0[YAFFS_NTNODES_LEVEL0]; */
 355
 356 };
 357
 358 typedef union yaffs_Tnode_union yaffs_Tnode;
 359
 360 struct yaffs_TnodeList_struct {
 361         struct yaffs_TnodeList_struct *next;
 362         yaffs_Tnode *tnodes;
 363 };
 364
 365 typedef struct yaffs_TnodeList_struct yaffs_TnodeList;
 366
 367 /*------------------------  Object -----------------------------*/
 368 /* An object can be one of:
 369  * - a directory (no data, has children links
 370  * - a regular file (data.... not prunes :->).
 371  * - a symlink [symbolic link] (the alias).
 372  * - a hard link
 373  */
 374
 375 typedef struct {
 376         __u32 fileSize;
 377         __u32 scannedFileSize;
 378         __u32 shrinkSize;
 379         int topLevel;
 380         yaffs_Tnode *top;
 381 } yaffs_FileStructure;
 382
 383 typedef struct {
 384         struct list_head children;      /* list of child links */
 385 } yaffs_DirectoryStructure;
 386
 387 typedef struct {
 388         YCHAR *alias;
 389 } yaffs_SymLinkStructure;
 390
 391 typedef struct {
 392         struct yaffs_ObjectStruct *equivalentObject;
 393         __u32 equivalentObjectId;
 394 } yaffs_HardLinkStructure;
 395
 396 typedef union {
 397         yaffs_FileStructure fileVariant;
 398         yaffs_DirectoryStructure directoryVariant;
 399         yaffs_SymLinkStructure symLinkVariant;
 400         yaffs_HardLinkStructure hardLinkVariant;
 401 } yaffs_ObjectVariant;
 402
 403 struct yaffs_ObjectStruct {
 404         __u8 deleted:1;         /* This should only apply to unlinked files. */
 405         __u8 softDeleted:1;     /* it has also been soft deleted */
 406         __u8 unlinked:1;        /* An unlinked file. The file should be in the unlinked directory.*/
 407         __u8 fake:1;            /* A fake object has no presence on NAND. */
 408         __u8 renameAllowed:1;   /* Some objects are not allowed to be renamed. */
 409         __u8 unlinkAllowed:1;
 410         __u8 dirty:1;           /* the object needs to be written to flash */
 411         __u8 valid:1;           /* When the file system is being loaded up, this
 412                                  * object might be created before the data
 413                                  * is available (ie. file data records appear before the header).
 414                                  */
 415         __u8 lazyLoaded:1;      /* This object has been lazy loaded and is missing some detail */
 416
 417         __u8 deferedFree:1;     /* For Linux kernel. Object is removed from NAND, but is
 418                                  * still in the inode cache. Free of object is defered.
 419                                  * until the inode is released.
 420                                  */
 421
 422         __u8 serial;            /* serial number of chunk in NAND. Cached here */
 423         __u16 sum;              /* sum of the name to speed searching */
 424
 425         struct yaffs_DeviceStruct *myDev;       /* The device I'm on */
 426
 427         struct list_head hashLink;      /* list of objects in this hash bucket */
 428
 429         struct list_head hardLinks;     /* all the equivalent hard linked objects */
 430
 431         /* directory structure stuff */
 432         /* also used for linking up the free list */
 433         struct yaffs_ObjectStruct *parent;
 434         struct list_head siblings;
 435
 436         /* Where's my object header in NAND? */
 437         int chunkId;
 438
 439         int nDataChunks;        /* Number of data chunks attached to the file. */
 440
 441         __u32 objectId;         /* the object id value */
 442
 443         __u32 yst_mode;
 444
 445 #ifdef CONFIG_YAFFS_SHORT_NAMES_IN_RAM
 446         YCHAR shortName[YAFFS_SHORT_NAME_LENGTH + 1];
 447 #endif
 448
 449 #ifndef __KERNEL__
 450         __u32 inUse;
 451 #endif
 452
 453 #ifdef CONFIG_YAFFS_WINCE
 454         __u32 win_ctime[2];
 455         __u32 win_mtime[2];
 456         __u32 win_atime[2];
 457 #else
 458         __u32 yst_uid;
 459         __u32 yst_gid;
 460         __u32 yst_atime;
 461         __u32 yst_mtime;
 462         __u32 yst_ctime;
 463 #endif
 464
 465         __u32 yst_rdev;
 466
 467 #ifdef __KERNEL__
 468         struct inode *myInode;
 469
 470 #endif
 471
 472         yaffs_ObjectType variantType;
 473
 474         yaffs_ObjectVariant variant;
 475
 476 };
 477
 478 typedef struct yaffs_ObjectStruct yaffs_Object;
 479
 480 struct yaffs_ObjectList_struct {
 481         yaffs_Object *objects;
 482         struct yaffs_ObjectList_struct *next;
 483 };
 484
 485 typedef struct yaffs_ObjectList_struct yaffs_ObjectList;
 486
 487 typedef struct {
 488         struct list_head list;
 489         int count;
 490 } yaffs_ObjectBucket;
 491
 492
 493 /* yaffs_CheckpointObject holds the definition of an object as dumped
 494  * by checkpointing.
 495  */
 496
 497 typedef struct {
 498         int structType;
 499         __u32 objectId;
 500         __u32 parentId;
 501         int chunkId;
 502
 503         yaffs_ObjectType variantType:3;
 504         __u8 deleted:1;
 505         __u8 softDeleted:1;
 506         __u8 unlinked:1;
 507         __u8 fake:1;
 508         __u8 renameAllowed:1;
 509         __u8 unlinkAllowed:1;
 510         __u8 serial;
 511
 512         int nDataChunks;
 513         __u32 fileSizeOrEquivalentObjectId;
 514
 515 }yaffs_CheckpointObject;
 516
 517 /*--------------------- Temporary buffers ----------------
 518  *
 519  * These are chunk-sized working buffers. Each device has a few
 520  */
 521
 522 typedef struct {
 523         __u8 *buffer;
 524         int line;       /* track from whence this buffer was allocated */
 525         int maxLine;
 526 } yaffs_TempBuffer;
 527
 528 /*----------------- Device ---------------------------------*/
 529
 530 struct yaffs_DeviceStruct {
 531         struct list_head devList;
 532         const char *name;
 533
 534         /* Entry parameters set up way early. Yaffs sets up the rest.*/
 535         int nDataBytesPerChunk; /* Should be a power of 2 >= 512 */
 536         int nChunksPerBlock;    /* does not need to be a power of 2 */
 537         int nBytesPerSpare;     /* spare area size */
 538         int startBlock;         /* Start block we're allowed to use */
 539         int endBlock;           /* End block we're allowed to use */
 540         int nReservedBlocks;    /* We want this tuneable so that we can reduce */
 541                                 /* reserved blocks on NOR and RAM. */
 542
 543
 544         /* Stuff used by the shared space checkpointing mechanism */
 545         /* If this value is zero, then this mechanism is disabled */
 546
 547         int nCheckpointReservedBlocks; /* Blocks to reserve for checkpoint data */
 548
 549
 550
 551
 552         int nShortOpCaches;     /* If <= 0, then short op caching is disabled, else
 553                                  * the number of short op caches (don't use too many)
 554                                  */
 555
 556         int useHeaderFileSize;  /* Flag to determine if we should use file sizes from the header */
 557
 558         int useNANDECC;         /* Flag to decide whether or not to use NANDECC */
 559
 560         void *genericDevice;    /* Pointer to device context
 561                                  * On an mtd this holds the mtd pointer.
 562                                  */
 563         void *superBlock;
 564
 565         /* NAND access functions (Must be set before calling YAFFS)*/
 566
 567         int (*writeChunkToNAND) (struct yaffs_DeviceStruct * dev,
 568                                  int chunkInNAND, const __u8 * data,
 569                                  const yaffs_Spare * spare);
 570         int (*readChunkFromNAND) (struct yaffs_DeviceStruct * dev,
 571                                   int chunkInNAND, __u8 * data,
 572                                   yaffs_Spare * spare);
 573         int (*eraseBlockInNAND) (struct yaffs_DeviceStruct * dev,
 574                                  int blockInNAND);
 575         int (*initialiseNAND) (struct yaffs_DeviceStruct * dev);
 576
 577 #ifdef CONFIG_YAFFS_YAFFS2
 578         int (*writeChunkWithTagsToNAND) (struct yaffs_DeviceStruct * dev,
 579                                          int chunkInNAND, const __u8 * data,
 580                                          const yaffs_ExtendedTags * tags);
 581         int (*readChunkWithTagsFromNAND) (struct yaffs_DeviceStruct * dev,
 582                                           int chunkInNAND, __u8 * data,
 583                                           yaffs_ExtendedTags * tags);
 584         int (*markNANDBlockBad) (struct yaffs_DeviceStruct * dev, int blockNo);
 585         int (*queryNANDBlock) (struct yaffs_DeviceStruct * dev, int blockNo,
 586                                yaffs_BlockState * state, int *sequenceNumber);
 587 #endif
 588
 589         int isYaffs2;
 590
 591         /* The removeObjectCallback function must be supplied by OS flavours that
 592          * need it. The Linux kernel does not use this, but yaffs direct does use
 593          * it to implement the faster readdir
 594          */
 595         void (*removeObjectCallback)(struct yaffs_ObjectStruct *obj);
 596
 597         /* Callback to mark the superblock dirsty */
 598         void (*markSuperBlockDirty)(void * superblock);
 599
 600         int wideTnodesDisabled; /* Set to disable wide tnodes */
 601
 602
 603         /* End of stuff that must be set before initialisation. */
 604
 605         /* Checkpoint control. Can be set before or after initialisation */
 606         __u8 skipCheckpointRead;
 607         __u8 skipCheckpointWrite;
 608
 609         /* Runtime parameters. Set up by YAFFS. */
 610
 611         __u16 chunkGroupBits;   /* 0 for devices <= 32MB. else log2(nchunks) - 16 */
 612         __u16 chunkGroupSize;   /* == 2^^chunkGroupBits */
 613
 614         /* Stuff to support wide tnodes */
 615         __u32 tnodeWidth;
 616         __u32 tnodeMask;
 617
 618         /* Stuff to support various file offses to chunk/offset translations */
 619         /* "Crumbs" for nDataBytesPerChunk not being a power of 2 */
 620         __u32 crumbMask;
 621         __u32 crumbShift;
 622         __u32 crumbsPerChunk;
 623
 624         /* Straight shifting for nDataBytesPerChunk being a power of 2 */
 625         __u32 chunkShift;
 626         __u32 chunkMask;
 627
 628
 629 #ifdef __KERNEL__
 630
 631         struct semaphore sem;   /* Semaphore for waiting on erasure.*/
 632         struct semaphore grossLock;     /* Gross locking semaphore */
 633         __u8 *spareBuffer;      /* For mtdif2 use. Don't know the size of the buffer
 634                                  * at compile time so we have to allocate it.
 635                                  */
 636         void (*putSuperFunc) (struct super_block * sb);
 637 #endif
 638
 639         int isMounted;
 640
 641         int isCheckpointed;
 642
 643
 644         /* Stuff to support block offsetting to support start block zero */
 645         int internalStartBlock;
 646         int internalEndBlock;
 647         int blockOffset;
 648         int chunkOffset;
 649
 650
 651         /* Runtime checkpointing stuff */
 652         int checkpointPageSequence;   /* running sequence number of checkpoint pages */
 653         int checkpointByteCount;
 654         int checkpointByteOffset;
 655         __u8 *checkpointBuffer;
 656         int checkpointOpenForWrite;
 657         int blocksInCheckpoint;
 658         int checkpointCurrentChunk;
 659         int checkpointCurrentBlock;
 660         int checkpointNextBlock;
 661         int *checkpointBlockList;
 662         int checkpointMaxBlocks;
 663         __u32 checkpointSum;
 664         __u32 checkpointXor;
 665
 666         /* Block Info */
 667         yaffs_BlockInfo *blockInfo;
 668         __u8 *chunkBits;        /* bitmap of chunks in use */
 669         unsigned blockInfoAlt:1;        /* was allocated using alternative strategy */
 670         unsigned chunkBitsAlt:1;        /* was allocated using alternative strategy */
 671         int chunkBitmapStride;  /* Number of bytes of chunkBits per block.
 672                                  * Must be consistent with nChunksPerBlock.
 673                                  */
 674
 675         int nErasedBlocks;
 676         int allocationBlock;    /* Current block being allocated off */
 677         __u32 allocationPage;
 678         int allocationBlockFinder;      /* Used to search for next allocation block */
 679
 680         /* Runtime state */
 681         int nTnodesCreated;
 682         yaffs_Tnode *freeTnodes;
 683         int nFreeTnodes;
 684         yaffs_TnodeList *allocatedTnodeList;
 685
 686         int isDoingGC;
 687
 688         int nObjectsCreated;
 689         yaffs_Object *freeObjects;
 690         int nFreeObjects;
 691
 692         yaffs_ObjectList *allocatedObjectList;
 693
 694         yaffs_ObjectBucket objectBucket[YAFFS_NOBJECT_BUCKETS];
 695
 696         int nFreeChunks;
 697
 698         int currentDirtyChecker;        /* Used to find current dirtiest block */
 699
 700         __u32 *gcCleanupList;   /* objects to delete at the end of a GC. */
 701         int nonAggressiveSkip;  /* GC state/mode */
 702
 703         /* Statistcs */
 704         int nPageWrites;
 705         int nPageReads;
 706         int nBlockErasures;
 707         int nErasureFailures;
 708         int nGCCopies;
 709         int garbageCollections;
 710         int passiveGarbageCollections;
 711         int nRetriedWrites;
 712         int nRetiredBlocks;
 713         int eccFixed;
 714         int eccUnfixed;
 715         int tagsEccFixed;
 716         int tagsEccUnfixed;
 717         int nDeletions;
 718         int nUnmarkedDeletions;
 719
 720         int hasPendingPrioritisedGCs; /* We think this device might have pending prioritised gcs */
 721
 722         /* Special directories */
 723         yaffs_Object *rootDir;
 724         yaffs_Object *lostNFoundDir;
 725
 726         /* Buffer areas for storing data to recover from write failures TODO
 727          *      __u8            bufferedData[YAFFS_CHUNKS_PER_BLOCK][YAFFS_BYTES_PER_CHUNK];
 728          *      yaffs_Spare bufferedSpare[YAFFS_CHUNKS_PER_BLOCK];
 729          */
 730
 731         int bufferedBlock;      /* Which block is buffered here? */
 732         int doingBufferedBlockRewrite;
 733
 734         yaffs_ChunkCache *srCache;
 735         int srLastUse;
 736
 737         int cacheHits;
 738
 739         /* Stuff for background deletion and unlinked files.*/
 740         yaffs_Object *unlinkedDir;      /* Directory where unlinked and deleted files live. */
 741         yaffs_Object *deletedDir;       /* Directory where deleted objects are sent to disappear. */
 742         yaffs_Object *unlinkedDeletion; /* Current file being background deleted.*/
 743         int nDeletedFiles;              /* Count of files awaiting deletion;*/
 744         int nUnlinkedFiles;             /* Count of unlinked files. */
 745         int nBackgroundDeletions;       /* Count of background deletions. */
 746
 747
 748         yaffs_TempBuffer tempBuffer[YAFFS_N_TEMP_BUFFERS];
 749         int maxTemp;
 750         int unmanagedTempAllocations;
 751         int unmanagedTempDeallocations;
 752
 753         /* yaffs2 runtime stuff */
 754         unsigned sequenceNumber;        /* Sequence number of currently allocating block */
 755         unsigned oldestDirtySequence;
 756
 757 };
 758
 759 typedef struct yaffs_DeviceStruct yaffs_Device;
 760
 761 /* The static layout of bllock usage etc is stored in the super block header */
 762 typedef struct {
 763         int StructType;
 764         int version;
 765         int checkpointStartBlock;
 766         int checkpointEndBlock;
 767         int startBlock;
 768         int endBlock;
 769         int rfu[100];
 770 } yaffs_SuperBlockHeader;
 771
 772 /* The CheckpointDevice structure holds the device information that changes at runtime and
 773  * must be preserved over unmount/mount cycles.
 774  */
 775 typedef struct {
 776         int structType;
 777         int nErasedBlocks;
 778         int allocationBlock;    /* Current block being allocated off */
 779         __u32 allocationPage;
 780         int nFreeChunks;
 781
 782         int nDeletedFiles;              /* Count of files awaiting deletion;*/
 783         int nUnlinkedFiles;             /* Count of unlinked files. */
 784         int nBackgroundDeletions;       /* Count of background deletions. */
 785
 786         /* yaffs2 runtime stuff */
 787         unsigned sequenceNumber;        /* Sequence number of currently allocating block */
 788         unsigned oldestDirtySequence;
 789
 790 } yaffs_CheckpointDevice;
 791
 792
 793 typedef struct {
 794     int structType;
 795     __u32 magic;
 796     __u32 version;
 797     __u32 head;
 798 } yaffs_CheckpointValidity;
 799
 800 /* Function to manipulate block info */
 801 static Y_INLINE yaffs_BlockInfo *yaffs_GetBlockInfo(yaffs_Device * dev, int blk)
 802 {
 803         if (blk < dev->internalStartBlock || blk > dev->internalEndBlock) {
 804                 T(YAFFS_TRACE_ERROR,
 805                   (TSTR
 806                    ("**>> yaffs: getBlockInfo block %d is not valid" TENDSTR),
 807                    blk));
 808                 YBUG();
 809         }
 810         return &dev->blockInfo[blk - dev->internalStartBlock];
 811 }
 812
 813 /*----------------------- YAFFS Functions -----------------------*/
 814
 815 int yaffs_GutsInitialise(yaffs_Device * dev);
 816 void yaffs_Deinitialise(yaffs_Device * dev);
 817
 818 int yaffs_GetNumberOfFreeChunks(yaffs_Device * dev);
 819
 820 int yaffs_RenameObject(yaffs_Object * oldDir, const YCHAR * oldName,
 821                        yaffs_Object * newDir, const YCHAR * newName);
 822
 823 int yaffs_Unlink(yaffs_Object * dir, const YCHAR * name);
 824 int yaffs_DeleteFile(yaffs_Object * obj);
 825
 826 int yaffs_GetObjectName(yaffs_Object * obj, YCHAR * name, int buffSize);
 827 int yaffs_GetObjectFileLength(yaffs_Object * obj);
 828 int yaffs_GetObjectInode(yaffs_Object * obj);
 829 unsigned yaffs_GetObjectType(yaffs_Object * obj);
 830 int yaffs_GetObjectLinkCount(yaffs_Object * obj);
 831
 832 int yaffs_SetAttributes(yaffs_Object * obj, struct iattr *attr);
 833 int yaffs_GetAttributes(yaffs_Object * obj, struct iattr *attr);
 834
 835 /* File operations */
 836 int yaffs_ReadDataFromFile(yaffs_Object * obj, __u8 * buffer, loff_t offset,
 837                            int nBytes);
 838 int yaffs_WriteDataToFile(yaffs_Object * obj, const __u8 * buffer, loff_t offset,
 839                           int nBytes, int writeThrough);
 840 int yaffs_ResizeFile(yaffs_Object * obj, loff_t newSize);
 841
 842 yaffs_Object *yaffs_MknodFile(yaffs_Object * parent, const YCHAR * name,
 843                               __u32 mode, __u32 uid, __u32 gid);
 844 int yaffs_FlushFile(yaffs_Object * obj, int updateTime);
 845
 846 /* Flushing and checkpointing */
 847 void yaffs_FlushEntireDeviceCache(yaffs_Device *dev);
 848
 849 int yaffs_CheckpointSave(yaffs_Device *dev);
 850 int yaffs_CheckpointRestore(yaffs_Device *dev);
 851
 852 /* Directory operations */
 853 yaffs_Object *yaffs_MknodDirectory(yaffs_Object * parent, const YCHAR * name,
 854                                    __u32 mode, __u32 uid, __u32 gid);
 855 yaffs_Object *yaffs_FindObjectByName(yaffs_Object * theDir, const YCHAR * name);
 856 int yaffs_ApplyToDirectoryChildren(yaffs_Object * theDir,
 857                                    int (*fn) (yaffs_Object *));
 858
 859 yaffs_Object *yaffs_FindObjectByNumber(yaffs_Device * dev, __u32 number);
 860
 861 /* Link operations */
 862 yaffs_Object *yaffs_Link(yaffs_Object * parent, const YCHAR * name,
 863                          yaffs_Object * equivalentObject);
 864
 865 yaffs_Object *yaffs_GetEquivalentObject(yaffs_Object * obj);
 866
 867 /* Symlink operations */
 868 yaffs_Object *yaffs_MknodSymLink(yaffs_Object * parent, const YCHAR * name,
 869                                  __u32 mode, __u32 uid, __u32 gid,
 870                                  const YCHAR * alias);
 871 YCHAR *yaffs_GetSymlinkAlias(yaffs_Object * obj);
 872
 873 /* Special inodes (fifos, sockets and devices) */
 874 yaffs_Object *yaffs_MknodSpecial(yaffs_Object * parent, const YCHAR * name,
 875                                  __u32 mode, __u32 uid, __u32 gid, __u32 rdev);
 876
 877 /* Special directories */
 878 yaffs_Object *yaffs_Root(yaffs_Device * dev);
 879 yaffs_Object *yaffs_LostNFound(yaffs_Device * dev);
 880
 881 #ifdef CONFIG_YAFFS_WINCE
 882 /* CONFIG_YAFFS_WINCE special stuff */
 883 void yfsd_WinFileTimeNow(__u32 target[2]);
 884 #endif
 885
 886 #ifdef __KERNEL__
 887
 888 void yaffs_HandleDeferedFree(yaffs_Object * obj);
 889 #endif
 890
 891 /* Debug dump  */
 892 int yaffs_DumpObject(yaffs_Object * obj);
 893
 894 void yaffs_GutsTest(yaffs_Device * dev);
 895
 896 /* A few useful functions */
 897 void yaffs_InitialiseTags(yaffs_ExtendedTags * tags);
 898 void yaffs_DeleteChunk(yaffs_Device * dev, int chunkId, int markNAND, int lyn);
 899 int yaffs_CheckFF(__u8 * buffer, int nBytes);
 900 void yaffs_HandleChunkError(yaffs_Device *dev, yaffs_BlockInfo *bi);
 901
 902 #endif