target/linux/generic-2.6/files-2.6.26/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            6
  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         unsigned blockState:4;  /* One of the above block states. NB use unsigned because enum is sometimes an int */
 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         /* The 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 #else
 335         __u32 roomToGrow[6];
 336
 337 #endif
 338         __u32 inbandShadowsObject;
 339         __u32 inbandIsShrink;
 340
 341         __u32 reservedSpace[2];
 342         int shadowsObject;      /* This object header shadows the specified object if > 0 */
 343
 344         /* isShrink applies to object headers written when we shrink the file (ie resize) */
 345         __u32 isShrink;
 346
 347 } yaffs_ObjectHeader;
 348
 349 /*--------------------------- Tnode -------------------------- */
 350
 351 union yaffs_Tnode_union {
 352 #ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
 353         union yaffs_Tnode_union *internal[YAFFS_NTNODES_INTERNAL + 1];
 354 #else
 355         union yaffs_Tnode_union *internal[YAFFS_NTNODES_INTERNAL];
 356 #endif
 357 /*      __u16 level0[YAFFS_NTNODES_LEVEL0]; */
 358
 359 };
 360
 361 typedef union yaffs_Tnode_union yaffs_Tnode;
 362
 363 struct yaffs_TnodeList_struct {
 364         struct yaffs_TnodeList_struct *next;
 365         yaffs_Tnode *tnodes;
 366 };
 367
 368 typedef struct yaffs_TnodeList_struct yaffs_TnodeList;
 369
 370 /*------------------------  Object -----------------------------*/
 371 /* An object can be one of:
 372  * - a directory (no data, has children links
 373  * - a regular file (data.... not prunes :->).
 374  * - a symlink [symbolic link] (the alias).
 375  * - a hard link
 376  */
 377
 378 typedef struct {
 379         __u32 fileSize;
 380         __u32 scannedFileSize;
 381         __u32 shrinkSize;
 382         int topLevel;
 383         yaffs_Tnode *top;
 384 } yaffs_FileStructure;
 385
 386 typedef struct {
 387         struct ylist_head children;     /* list of child links */
 388 } yaffs_DirectoryStructure;
 389
 390 typedef struct {
 391         YCHAR *alias;
 392 } yaffs_SymLinkStructure;
 393
 394 typedef struct {
 395         struct yaffs_ObjectStruct *equivalentObject;
 396         __u32 equivalentObjectId;
 397 } yaffs_HardLinkStructure;
 398
 399 typedef union {
 400         yaffs_FileStructure fileVariant;
 401         yaffs_DirectoryStructure directoryVariant;
 402         yaffs_SymLinkStructure symLinkVariant;
 403         yaffs_HardLinkStructure hardLinkVariant;
 404 } yaffs_ObjectVariant;
 405
 406 struct yaffs_ObjectStruct {
 407         __u8 deleted:1;         /* This should only apply to unlinked files. */
 408         __u8 softDeleted:1;     /* it has also been soft deleted */
 409         __u8 unlinked:1;        /* An unlinked file. The file should be in the unlinked directory.*/
 410         __u8 fake:1;            /* A fake object has no presence on NAND. */
 411         __u8 renameAllowed:1;   /* Some objects are not allowed to be renamed. */
 412         __u8 unlinkAllowed:1;
 413         __u8 dirty:1;           /* the object needs to be written to flash */
 414         __u8 valid:1;           /* When the file system is being loaded up, this
 415                                  * object might be created before the data
 416                                  * is available (ie. file data records appear before the header).
 417                                  */
 418         __u8 lazyLoaded:1;      /* This object has been lazy loaded and is missing some detail */
 419
 420         __u8 deferedFree:1;     /* For Linux kernel. Object is removed from NAND, but is
 421                                  * still in the inode cache. Free of object is defered.
 422                                  * until the inode is released.
 423                                  */
 424
 425         __u8 serial;            /* serial number of chunk in NAND. Cached here */
 426         __u16 sum;              /* sum of the name to speed searching */
 427
 428         struct yaffs_DeviceStruct *myDev;       /* The device I'm on */
 429
 430         struct ylist_head hashLink;     /* list of objects in this hash bucket */
 431
 432         struct ylist_head hardLinks;    /* all the equivalent hard linked objects */
 433
 434         /* directory structure stuff */
 435         /* also used for linking up the free list */
 436         struct yaffs_ObjectStruct *parent;
 437         struct ylist_head siblings;
 438
 439         /* Where's my object header in NAND? */
 440         int chunkId;
 441
 442         int nDataChunks;        /* Number of data chunks attached to the file. */
 443
 444         __u32 objectId;         /* the object id value */
 445
 446         __u32 yst_mode;
 447
 448 #ifdef CONFIG_YAFFS_SHORT_NAMES_IN_RAM
 449         YCHAR shortName[YAFFS_SHORT_NAME_LENGTH + 1];
 450 #endif
 451
 452 #ifndef __KERNEL__
 453         __u32 inUse;
 454 #endif
 455
 456 #ifdef CONFIG_YAFFS_WINCE
 457         __u32 win_ctime[2];
 458         __u32 win_mtime[2];
 459         __u32 win_atime[2];
 460 #else
 461         __u32 yst_uid;
 462         __u32 yst_gid;
 463         __u32 yst_atime;
 464         __u32 yst_mtime;
 465         __u32 yst_ctime;
 466 #endif
 467
 468         __u32 yst_rdev;
 469
 470 #ifdef __KERNEL__
 471         struct inode *myInode;
 472
 473 #endif
 474
 475         yaffs_ObjectType variantType;
 476
 477         yaffs_ObjectVariant variant;
 478
 479 };
 480
 481 typedef struct yaffs_ObjectStruct yaffs_Object;
 482
 483 struct yaffs_ObjectList_struct {
 484         yaffs_Object *objects;
 485         struct yaffs_ObjectList_struct *next;
 486 };
 487
 488 typedef struct yaffs_ObjectList_struct yaffs_ObjectList;
 489
 490 typedef struct {
 491         struct ylist_head list;
 492         int count;
 493 } yaffs_ObjectBucket;
 494
 495
 496 /* yaffs_CheckpointObject holds the definition of an object as dumped
 497  * by checkpointing.
 498  */
 499
 500 typedef struct {
 501         int structType;
 502         __u32 objectId;
 503         __u32 parentId;
 504         int chunkId;
 505
 506         yaffs_ObjectType variantType:3;
 507         __u8 deleted:1;
 508         __u8 softDeleted:1;
 509         __u8 unlinked:1;
 510         __u8 fake:1;
 511         __u8 renameAllowed:1;
 512         __u8 unlinkAllowed:1;
 513         __u8 serial;
 514
 515         int nDataChunks;
 516         __u32 fileSizeOrEquivalentObjectId;
 517
 518 }yaffs_CheckpointObject;
 519
 520 /*--------------------- Temporary buffers ----------------
 521  *
 522  * These are chunk-sized working buffers. Each device has a few
 523  */
 524
 525 typedef struct {
 526         __u8 *buffer;
 527         int line;       /* track from whence this buffer was allocated */
 528         int maxLine;
 529 } yaffs_TempBuffer;
 530
 531 /*----------------- Device ---------------------------------*/
 532
 533 struct yaffs_DeviceStruct {
 534         struct ylist_head devList;
 535         const char *name;
 536
 537         /* Entry parameters set up way early. Yaffs sets up the rest.*/
 538         int nDataBytesPerChunk; /* Should be a power of 2 >= 512 */
 539         int nChunksPerBlock;    /* does not need to be a power of 2 */
 540         int nBytesPerSpare;     /* spare area size */
 541         int startBlock;         /* Start block we're allowed to use */
 542         int endBlock;           /* End block we're allowed to use */
 543         int nReservedBlocks;    /* We want this tuneable so that we can reduce */
 544                                 /* reserved blocks on NOR and RAM. */
 545
 546
 547         /* Stuff used by the shared space checkpointing mechanism */
 548         /* If this value is zero, then this mechanism is disabled */
 549
 550 //      int nCheckpointReservedBlocks; /* Blocks to reserve for checkpoint data */
 551
 552
 553
 554
 555         int nShortOpCaches;     /* If <= 0, then short op caching is disabled, else
 556                                  * the number of short op caches (don't use too many)
 557                                  */
 558
 559         int useHeaderFileSize;  /* Flag to determine if we should use file sizes from the header */
 560
 561         int useNANDECC;         /* Flag to decide whether or not to use NANDECC */
 562
 563         void *genericDevice;    /* Pointer to device context
 564                                  * On an mtd this holds the mtd pointer.
 565                                  */
 566         void *superBlock;
 567
 568         /* NAND access functions (Must be set before calling YAFFS)*/
 569
 570         int (*writeChunkToNAND) (struct yaffs_DeviceStruct * dev,
 571                                  int chunkInNAND, const __u8 * data,
 572                                  const yaffs_Spare * spare);
 573         int (*readChunkFromNAND) (struct yaffs_DeviceStruct * dev,
 574                                   int chunkInNAND, __u8 * data,
 575                                   yaffs_Spare * spare);
 576         int (*eraseBlockInNAND) (struct yaffs_DeviceStruct * dev,
 577                                  int blockInNAND);
 578         int (*initialiseNAND) (struct yaffs_DeviceStruct * dev);
 579
 580 #ifdef CONFIG_YAFFS_YAFFS2
 581         int (*writeChunkWithTagsToNAND) (struct yaffs_DeviceStruct * dev,
 582                                          int chunkInNAND, const __u8 * data,
 583                                          const yaffs_ExtendedTags * tags);
 584         int (*readChunkWithTagsFromNAND) (struct yaffs_DeviceStruct * dev,
 585                                           int chunkInNAND, __u8 * data,
 586                                           yaffs_ExtendedTags * tags);
 587         int (*markNANDBlockBad) (struct yaffs_DeviceStruct * dev, int blockNo);
 588         int (*queryNANDBlock) (struct yaffs_DeviceStruct * dev, int blockNo,
 589                                yaffs_BlockState * state, __u32 *sequenceNumber);
 590 #endif
 591
 592         int isYaffs2;
 593
 594         /* The removeObjectCallback function must be supplied by OS flavours that
 595          * need it. The Linux kernel does not use this, but yaffs direct does use
 596          * it to implement the faster readdir
 597          */
 598         void (*removeObjectCallback)(struct yaffs_ObjectStruct *obj);
 599
 600         /* Callback to mark the superblock dirsty */
 601         void (*markSuperBlockDirty)(void * superblock);
 602
 603         int wideTnodesDisabled; /* Set to disable wide tnodes */
 604
 605         YCHAR *pathDividers;    /* String of legal path dividers */
 606
 607         /* End of stuff that must be set before initialisation. */
 608
 609         /* Checkpoint control. Can be set before or after initialisation */
 610         __u8 skipCheckpointRead;
 611         __u8 skipCheckpointWrite;
 612
 613         /* Runtime parameters. Set up by YAFFS. */
 614
 615         __u16 chunkGroupBits;   /* 0 for devices <= 32MB. else log2(nchunks) - 16 */
 616         __u16 chunkGroupSize;   /* == 2^^chunkGroupBits */
 617
 618         /* Stuff to support wide tnodes */
 619         __u32 tnodeWidth;
 620         __u32 tnodeMask;
 621
 622         /* Stuff for figuring out file offset to chunk conversions */
 623         __u32 chunkShift; /* Shift value */
 624         __u32 chunkDiv;   /* Divisor after shifting: 1 for power-of-2 sizes */
 625         __u32 chunkMask;  /* Mask to use for power-of-2 case */
 626
 627         /* Stuff to handle inband tags */
 628         int inbandTags;
 629         __u32 totalBytesPerChunk;
 630
 631 #ifdef __KERNEL__
 632
 633         struct semaphore sem;   /* Semaphore for waiting on erasure.*/
 634         struct semaphore grossLock;     /* Gross locking semaphore */
 635         __u8 *spareBuffer;      /* For mtdif2 use. Don't know the size of the buffer
 636                                  * at compile time so we have to allocate it.
 637                                  */
 638         void (*putSuperFunc) (struct super_block * sb);
 639 #endif
 640
 641         int isMounted;
 642
 643         int isCheckpointed;
 644
 645
 646         /* Stuff to support block offsetting to support start block zero */
 647         int internalStartBlock;
 648         int internalEndBlock;
 649         int blockOffset;
 650         int chunkOffset;
 651
 652
 653         /* Runtime checkpointing stuff */
 654         int checkpointPageSequence;   /* running sequence number of checkpoint pages */
 655         int checkpointByteCount;
 656         int checkpointByteOffset;
 657         __u8 *checkpointBuffer;
 658         int checkpointOpenForWrite;
 659         int blocksInCheckpoint;
 660         int checkpointCurrentChunk;
 661         int checkpointCurrentBlock;
 662         int checkpointNextBlock;
 663         int *checkpointBlockList;
 664         int checkpointMaxBlocks;
 665         __u32 checkpointSum;
 666         __u32 checkpointXor;
 667
 668         int nCheckpointBlocksRequired; /* Number of blocks needed to store current checkpoint set */
 669
 670         /* Block Info */
 671         yaffs_BlockInfo *blockInfo;
 672         __u8 *chunkBits;        /* bitmap of chunks in use */
 673         unsigned blockInfoAlt:1;        /* was allocated using alternative strategy */
 674         unsigned chunkBitsAlt:1;        /* was allocated using alternative strategy */
 675         int chunkBitmapStride;  /* Number of bytes of chunkBits per block.
 676                                  * Must be consistent with nChunksPerBlock.
 677                                  */
 678
 679         int nErasedBlocks;
 680         int allocationBlock;    /* Current block being allocated off */
 681         __u32 allocationPage;
 682         int allocationBlockFinder;      /* Used to search for next allocation block */
 683
 684         /* Runtime state */
 685         int nTnodesCreated;
 686         yaffs_Tnode *freeTnodes;
 687         int nFreeTnodes;
 688         yaffs_TnodeList *allocatedTnodeList;
 689
 690         int isDoingGC;
 691
 692         int nObjectsCreated;
 693         yaffs_Object *freeObjects;
 694         int nFreeObjects;
 695
 696         yaffs_ObjectList *allocatedObjectList;
 697
 698         yaffs_ObjectBucket objectBucket[YAFFS_NOBJECT_BUCKETS];
 699
 700         int nFreeChunks;
 701
 702         int currentDirtyChecker;        /* Used to find current dirtiest block */
 703
 704         __u32 *gcCleanupList;   /* objects to delete at the end of a GC. */
 705         int nonAggressiveSkip;  /* GC state/mode */
 706
 707         /* Statistcs */
 708         int nPageWrites;
 709         int nPageReads;
 710         int nBlockErasures;
 711         int nErasureFailures;
 712         int nGCCopies;
 713         int garbageCollections;
 714         int passiveGarbageCollections;
 715         int nRetriedWrites;
 716         int nRetiredBlocks;
 717         int eccFixed;
 718         int eccUnfixed;
 719         int tagsEccFixed;
 720         int tagsEccUnfixed;
 721         int nDeletions;
 722         int nUnmarkedDeletions;
 723
 724         int hasPendingPrioritisedGCs; /* We think this device might have pending prioritised gcs */
 725
 726         /* Special directories */
 727         yaffs_Object *rootDir;
 728         yaffs_Object *lostNFoundDir;
 729
 730         /* Buffer areas for storing data to recover from write failures TODO
 731          *      __u8            bufferedData[YAFFS_CHUNKS_PER_BLOCK][YAFFS_BYTES_PER_CHUNK];
 732          *      yaffs_Spare bufferedSpare[YAFFS_CHUNKS_PER_BLOCK];
 733          */
 734
 735         int bufferedBlock;      /* Which block is buffered here? */
 736         int doingBufferedBlockRewrite;
 737
 738         yaffs_ChunkCache *srCache;
 739         int srLastUse;
 740
 741         int cacheHits;
 742
 743         /* Stuff for background deletion and unlinked files.*/
 744         yaffs_Object *unlinkedDir;      /* Directory where unlinked and deleted files live. */
 745         yaffs_Object *deletedDir;       /* Directory where deleted objects are sent to disappear. */
 746         yaffs_Object *unlinkedDeletion; /* Current file being background deleted.*/
 747         int nDeletedFiles;              /* Count of files awaiting deletion;*/
 748         int nUnlinkedFiles;             /* Count of unlinked files. */
 749         int nBackgroundDeletions;       /* Count of background deletions. */
 750
 751
 752         /* Temporary buffer management */
 753         yaffs_TempBuffer tempBuffer[YAFFS_N_TEMP_BUFFERS];
 754         int maxTemp;
 755         int tempInUse;
 756         int unmanagedTempAllocations;
 757         int unmanagedTempDeallocations;
 758
 759         /* yaffs2 runtime stuff */
 760         unsigned sequenceNumber;        /* Sequence number of currently allocating block */
 761         unsigned oldestDirtySequence;
 762
 763 };
 764
 765 typedef struct yaffs_DeviceStruct yaffs_Device;
 766
 767 /* The static layout of block usage etc is stored in the super block header */
 768 typedef struct {
 769         int StructType;
 770         int version;
 771         int checkpointStartBlock;
 772         int checkpointEndBlock;
 773         int startBlock;
 774         int endBlock;
 775         int rfu[100];
 776 } yaffs_SuperBlockHeader;
 777
 778 /* The CheckpointDevice structure holds the device information that changes at runtime and
 779  * must be preserved over unmount/mount cycles.
 780  */
 781 typedef struct {
 782         int structType;
 783         int nErasedBlocks;
 784         int allocationBlock;    /* Current block being allocated off */
 785         __u32 allocationPage;
 786         int nFreeChunks;
 787
 788         int nDeletedFiles;              /* Count of files awaiting deletion;*/
 789         int nUnlinkedFiles;             /* Count of unlinked files. */
 790         int nBackgroundDeletions;       /* Count of background deletions. */
 791
 792         /* yaffs2 runtime stuff */
 793         unsigned sequenceNumber;        /* Sequence number of currently allocating block */
 794         unsigned oldestDirtySequence;
 795
 796 } yaffs_CheckpointDevice;
 797
 798
 799 typedef struct {
 800     int structType;
 801     __u32 magic;
 802     __u32 version;
 803     __u32 head;
 804 } yaffs_CheckpointValidity;
 805
 806
 807 /*----------------------- YAFFS Functions -----------------------*/
 808
 809 int yaffs_GutsInitialise(yaffs_Device * dev);
 810 void yaffs_Deinitialise(yaffs_Device * dev);
 811
 812 int yaffs_GetNumberOfFreeChunks(yaffs_Device * dev);
 813
 814 int yaffs_RenameObject(yaffs_Object * oldDir, const YCHAR * oldName,
 815                        yaffs_Object * newDir, const YCHAR * newName);
 816
 817 int yaffs_Unlink(yaffs_Object * dir, const YCHAR * name);
 818 int yaffs_DeleteFile(yaffs_Object * obj);
 819
 820 int yaffs_GetObjectName(yaffs_Object * obj, YCHAR * name, int buffSize);
 821 int yaffs_GetObjectFileLength(yaffs_Object * obj);
 822 int yaffs_GetObjectInode(yaffs_Object * obj);
 823 unsigned yaffs_GetObjectType(yaffs_Object * obj);
 824 int yaffs_GetObjectLinkCount(yaffs_Object * obj);
 825
 826 int yaffs_SetAttributes(yaffs_Object * obj, struct iattr *attr);
 827 int yaffs_GetAttributes(yaffs_Object * obj, struct iattr *attr);
 828
 829 /* File operations */
 830 int yaffs_ReadDataFromFile(yaffs_Object * obj, __u8 * buffer, loff_t offset,
 831                            int nBytes);
 832 int yaffs_WriteDataToFile(yaffs_Object * obj, const __u8 * buffer, loff_t offset,
 833                           int nBytes, int writeThrough);
 834 int yaffs_ResizeFile(yaffs_Object * obj, loff_t newSize);
 835
 836 yaffs_Object *yaffs_MknodFile(yaffs_Object * parent, const YCHAR * name,
 837                               __u32 mode, __u32 uid, __u32 gid);
 838 int yaffs_FlushFile(yaffs_Object * obj, int updateTime);
 839
 840 /* Flushing and checkpointing */
 841 void yaffs_FlushEntireDeviceCache(yaffs_Device *dev);
 842
 843 int yaffs_CheckpointSave(yaffs_Device *dev);
 844 int yaffs_CheckpointRestore(yaffs_Device *dev);
 845
 846 /* Directory operations */
 847 yaffs_Object *yaffs_MknodDirectory(yaffs_Object * parent, const YCHAR * name,
 848                                    __u32 mode, __u32 uid, __u32 gid);
 849 yaffs_Object *yaffs_FindObjectByName(yaffs_Object * theDir, const YCHAR * name);
 850 int yaffs_ApplyToDirectoryChildren(yaffs_Object * theDir,
 851                                    int (*fn) (yaffs_Object *));
 852
 853 yaffs_Object *yaffs_FindObjectByNumber(yaffs_Device * dev, __u32 number);
 854
 855 /* Link operations */
 856 yaffs_Object *yaffs_Link(yaffs_Object * parent, const YCHAR * name,
 857                          yaffs_Object * equivalentObject);
 858
 859 yaffs_Object *yaffs_GetEquivalentObject(yaffs_Object * obj);
 860
 861 /* Symlink operations */
 862 yaffs_Object *yaffs_MknodSymLink(yaffs_Object * parent, const YCHAR * name,
 863                                  __u32 mode, __u32 uid, __u32 gid,
 864                                  const YCHAR * alias);
 865 YCHAR *yaffs_GetSymlinkAlias(yaffs_Object * obj);
 866
 867 /* Special inodes (fifos, sockets and devices) */
 868 yaffs_Object *yaffs_MknodSpecial(yaffs_Object * parent, const YCHAR * name,
 869                                  __u32 mode, __u32 uid, __u32 gid, __u32 rdev);
 870
 871 /* Special directories */
 872 yaffs_Object *yaffs_Root(yaffs_Device * dev);
 873 yaffs_Object *yaffs_LostNFound(yaffs_Device * dev);
 874
 875 #ifdef CONFIG_YAFFS_WINCE
 876 /* CONFIG_YAFFS_WINCE special stuff */
 877 void yfsd_WinFileTimeNow(__u32 target[2]);
 878 #endif
 879
 880 #ifdef __KERNEL__
 881
 882 void yaffs_HandleDeferedFree(yaffs_Object * obj);
 883 #endif
 884
 885 /* Debug dump  */
 886 int yaffs_DumpObject(yaffs_Object * obj);
 887
 888 void yaffs_GutsTest(yaffs_Device * dev);
 889
 890 /* A few useful functions */
 891 void yaffs_InitialiseTags(yaffs_ExtendedTags * tags);
 892 void yaffs_DeleteChunk(yaffs_Device * dev, int chunkId, int markNAND, int lyn);
 893 int yaffs_CheckFF(__u8 * buffer, int nBytes);
 894 void yaffs_HandleChunkError(yaffs_Device *dev, yaffs_BlockInfo *bi);
 895
 896 __u8 *yaffs_GetTempBuffer(yaffs_Device * dev, int lineNo);
 897 void yaffs_ReleaseTempBuffer(yaffs_Device * dev, __u8 * buffer, int lineNo);
 898
 899 #endif