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) 2002-2011 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 "yportenv.h"
  20
  21 #define YAFFS_OK        1
  22 #define YAFFS_FAIL  0
  23
  24 /* Give us a  Y=0x59,
  25  * Give us an A=0x41,
  26  * Give us an FF=0xff
  27  * Give us an S=0x53
  28  * And what have we got...
  29  */
  30 #define YAFFS_MAGIC                     0x5941ff53
  31
  32 /*
  33  * Tnodes form a tree with the tnodes in "levels"
  34  * Levels greater than 0 hold 8 slots which point to other tnodes.
  35  * Those at level 0 hold 16 slots which point to chunks in NAND.
  36  *
  37  * A maximum level of 8 thust supports files of size up to:
  38  *
  39  * 2^(3*MAX_LEVEL+4)
  40  *
  41  * Thus a max level of 8 supports files with up to 2^^28 chunks which gives
  42  * a maximum file size of around 512Gbytees with 2k chunks.
  43  */
  44 #define YAFFS_NTNODES_LEVEL0            16
  45 #define YAFFS_TNODES_LEVEL0_BITS        4
  46 #define YAFFS_TNODES_LEVEL0_MASK        0xf
  47
  48 #define YAFFS_NTNODES_INTERNAL          (YAFFS_NTNODES_LEVEL0 / 2)
  49 #define YAFFS_TNODES_INTERNAL_BITS      (YAFFS_TNODES_LEVEL0_BITS - 1)
  50 #define YAFFS_TNODES_INTERNAL_MASK      0x7
  51 #define YAFFS_TNODES_MAX_LEVEL          8
  52 #define YAFFS_TNODES_MAX_BITS           (YAFFS_TNODES_LEVEL0_BITS + \
  53                                         YAFFS_TNODES_INTERNAL_BITS * \
  54                                         YAFFS_TNODES_MAX_LEVEL)
  55 #define YAFFS_MAX_CHUNK_ID              ((1 << YAFFS_TNODES_MAX_BITS) - 1)
  56
  57 #define YAFFS_MAX_FILE_SIZE_32          0x7fffffff
  58
  59 /* Constants for YAFFS1 mode */
  60 #define YAFFS_BYTES_PER_SPARE           16
  61 #define YAFFS_BYTES_PER_CHUNK           512
  62 #define YAFFS_CHUNK_SIZE_SHIFT          9
  63 #define YAFFS_CHUNKS_PER_BLOCK          32
  64 #define YAFFS_BYTES_PER_BLOCK   (YAFFS_CHUNKS_PER_BLOCK*YAFFS_BYTES_PER_CHUNK)
  65
  66 #define YAFFS_MIN_YAFFS2_CHUNK_SIZE     1024
  67 #define YAFFS_MIN_YAFFS2_SPARE_SIZE     32
  68
  69
  70
  71 #define YAFFS_ALLOCATION_NOBJECTS       100
  72 #define YAFFS_ALLOCATION_NTNODES        100
  73 #define YAFFS_ALLOCATION_NLINKS         100
  74
  75 #define YAFFS_NOBJECT_BUCKETS           256
  76
  77 #define YAFFS_OBJECT_SPACE              0x40000
  78 #define YAFFS_MAX_OBJECT_ID             (YAFFS_OBJECT_SPACE - 1)
  79
  80 /* Binary data version stamps */
  81 #define YAFFS_SUMMARY_VERSION           1
  82 #define YAFFS_CHECKPOINT_VERSION        7
  83
  84 #ifdef CONFIG_YAFFS_UNICODE
  85 #define YAFFS_MAX_NAME_LENGTH           127
  86 #define YAFFS_MAX_ALIAS_LENGTH          79
  87 #else
  88 #define YAFFS_MAX_NAME_LENGTH           255
  89 #define YAFFS_MAX_ALIAS_LENGTH          159
  90 #endif
  91
  92 #define YAFFS_SHORT_NAME_LENGTH         15
  93
  94 /* Some special object ids for pseudo objects */
  95 #define YAFFS_OBJECTID_ROOT             1
  96 #define YAFFS_OBJECTID_LOSTNFOUND       2
  97 #define YAFFS_OBJECTID_UNLINKED         3
  98 #define YAFFS_OBJECTID_DELETED          4
  99
 100 /* Fake object Id for summary data */
 101 #define YAFFS_OBJECTID_SUMMARY          0x10
 102
 103 /* Pseudo object ids for checkpointing */
 104 #define YAFFS_OBJECTID_CHECKPOINT_DATA  0x20
 105 #define YAFFS_SEQUENCE_CHECKPOINT_DATA  0x21
 106
 107 #define YAFFS_MAX_SHORT_OP_CACHES       20
 108
 109 #define YAFFS_N_TEMP_BUFFERS            6
 110
 111 /* We limit the number attempts at sucessfully saving a chunk of data.
 112  * Small-page devices have 32 pages per block; large-page devices have 64.
 113  * Default to something in the order of 5 to 10 blocks worth of chunks.
 114  */
 115 #define YAFFS_WR_ATTEMPTS               (5*64)
 116
 117 /* Sequence numbers are used in YAFFS2 to determine block allocation order.
 118  * The range is limited slightly to help distinguish bad numbers from good.
 119  * This also allows us to perhaps in the future use special numbers for
 120  * special purposes.
 121  * EFFFFF00 allows the allocation of 8 blocks/second (~1Mbytes) for 15 years,
 122  * and is a larger number than the lifetime of a 2GB device.
 123  */
 124 #define YAFFS_LOWEST_SEQUENCE_NUMBER    0x00001000
 125 #define YAFFS_HIGHEST_SEQUENCE_NUMBER   0xefffff00
 126
 127 /* Special sequence number for bad block that failed to be marked bad */
 128 #define YAFFS_SEQUENCE_BAD_BLOCK        0xffff0000
 129
 130 /* ChunkCache is used for short read/write operations.*/
 131 struct yaffs_cache {
 132         struct yaffs_obj *object;
 133         int chunk_id;
 134         int last_use;
 135         int dirty;
 136         int n_bytes;            /* Only valid if the cache is dirty */
 137         int locked;             /* Can't push out or flush while locked. */
 138         u8 *data;
 139 };
 140
 141 /* yaffs1 tags structures in RAM
 142  * NB This uses bitfield. Bitfields should not straddle a u32 boundary
 143  * otherwise the structure size will get blown out.
 144  */
 145
 146 struct yaffs_tags {
 147         u32 chunk_id:20;
 148         u32 serial_number:2;
 149         u32 n_bytes_lsb:10;
 150         u32 obj_id:18;
 151         u32 ecc:12;
 152         u32 n_bytes_msb:2;
 153 };
 154
 155 union yaffs_tags_union {
 156         struct yaffs_tags as_tags;
 157         u8 as_bytes[8];
 158 };
 159
 160
 161 /* Stuff used for extended tags in YAFFS2 */
 162
 163 enum yaffs_ecc_result {
 164         YAFFS_ECC_RESULT_UNKNOWN,
 165         YAFFS_ECC_RESULT_NO_ERROR,
 166         YAFFS_ECC_RESULT_FIXED,
 167         YAFFS_ECC_RESULT_UNFIXED
 168 };
 169
 170 enum yaffs_obj_type {
 171         YAFFS_OBJECT_TYPE_UNKNOWN,
 172         YAFFS_OBJECT_TYPE_FILE,
 173         YAFFS_OBJECT_TYPE_SYMLINK,
 174         YAFFS_OBJECT_TYPE_DIRECTORY,
 175         YAFFS_OBJECT_TYPE_HARDLINK,
 176         YAFFS_OBJECT_TYPE_SPECIAL
 177 };
 178
 179 #define YAFFS_OBJECT_TYPE_MAX YAFFS_OBJECT_TYPE_SPECIAL
 180
 181 struct yaffs_ext_tags {
 182         unsigned chunk_used;    /*  Status of the chunk: used or unused */
 183         unsigned obj_id;        /* If 0 this is not used */
 184         unsigned chunk_id;      /* If 0 this is a header, else a data chunk */
 185         unsigned n_bytes;       /* Only valid for data chunks */
 186
 187         /* The following stuff only has meaning when we read */
 188         enum yaffs_ecc_result ecc_result;
 189         unsigned block_bad;
 190
 191         /* YAFFS 1 stuff */
 192         unsigned is_deleted;    /* The chunk is marked deleted */
 193         unsigned serial_number; /* Yaffs1 2-bit serial number */
 194
 195         /* YAFFS2 stuff */
 196         unsigned seq_number;    /* The sequence number of this block */
 197
 198         /* Extra info if this is an object header (YAFFS2 only) */
 199
 200         unsigned extra_available;       /* Extra info available if not zero */
 201         unsigned extra_parent_id;       /* The parent object */
 202         unsigned extra_is_shrink;       /* Is it a shrink header? */
 203         unsigned extra_shadows; /* Does this shadow another object? */
 204
 205         enum yaffs_obj_type extra_obj_type;     /* What object type? */
 206
 207         loff_t extra_file_size;         /* Length if it is a file */
 208         unsigned extra_equiv_id;        /* Equivalent object for a hard link */
 209 };
 210
 211 /* Spare structure for YAFFS1 */
 212 struct yaffs_spare {
 213         u8 tb0;
 214         u8 tb1;
 215         u8 tb2;
 216         u8 tb3;
 217         u8 page_status;         /* set to 0 to delete the chunk */
 218         u8 block_status;
 219         u8 tb4;
 220         u8 tb5;
 221         u8 ecc1[3];
 222         u8 tb6;
 223         u8 tb7;
 224         u8 ecc2[3];
 225 };
 226
 227 /*Special structure for passing through to mtd */
 228 struct yaffs_nand_spare {
 229         struct yaffs_spare spare;
 230         int eccres1;
 231         int eccres2;
 232 };
 233
 234 /* Block data in RAM */
 235
 236 enum yaffs_block_state {
 237         YAFFS_BLOCK_STATE_UNKNOWN = 0,
 238
 239         YAFFS_BLOCK_STATE_SCANNING,
 240         /* Being scanned */
 241
 242         YAFFS_BLOCK_STATE_NEEDS_SCAN,
 243         /* The block might have something on it (ie it is allocating or full,
 244          * perhaps empty) but it needs to be scanned to determine its true
 245          * state.
 246          * This state is only valid during scanning.
 247          * NB We tolerate empty because the pre-scanner might be incapable of
 248          * deciding
 249          * However, if this state is returned on a YAFFS2 device,
 250          * then we expect a sequence number
 251          */
 252
 253         YAFFS_BLOCK_STATE_EMPTY,
 254         /* This block is empty */
 255
 256         YAFFS_BLOCK_STATE_ALLOCATING,
 257         /* This block is partially allocated.
 258          * At least one page holds valid data.
 259          * This is the one currently being used for page
 260          * allocation. Should never be more than one of these.
 261          * If a block is only partially allocated at mount it is treated as
 262          * full.
 263          */
 264
 265         YAFFS_BLOCK_STATE_FULL,
 266         /* All the pages in this block have been allocated.
 267          * If a block was only partially allocated when mounted we treat
 268          * it as fully allocated.
 269          */
 270
 271         YAFFS_BLOCK_STATE_DIRTY,
 272         /* The block was full and now all chunks have been deleted.
 273          * Erase me, reuse me.
 274          */
 275
 276         YAFFS_BLOCK_STATE_CHECKPOINT,
 277         /* This block is assigned to holding checkpoint data. */
 278
 279         YAFFS_BLOCK_STATE_COLLECTING,
 280         /* This block is being garbage collected */
 281
 282         YAFFS_BLOCK_STATE_DEAD
 283             /* This block has failed and is not in use */
 284 };
 285
 286 #define YAFFS_NUMBER_OF_BLOCK_STATES (YAFFS_BLOCK_STATE_DEAD + 1)
 287
 288 struct yaffs_block_info {
 289
 290         s32 soft_del_pages:10;  /* number of soft deleted pages */
 291         s32 pages_in_use:10;    /* number of pages in use */
 292         u32 block_state:4;      /* One of the above block states. */
 293                                 /* NB use unsigned because enum is sometimes
 294                                  * an int */
 295         u32 needs_retiring:1;   /* Data has failed on this block, */
 296                                 /*need to get valid data off and retire*/
 297         u32 skip_erased_check:1;/* Skip the erased check on this block */
 298         u32 gc_prioritise:1;    /* An ECC check or blank check has failed.
 299                                    Block should be prioritised for GC */
 300         u32 chunk_error_strikes:3;      /* How many times we've had ecc etc
 301                                 failures on this block and tried to reuse it */
 302         u32 has_summary:1;      /* The block has a summary */
 303
 304         u32 has_shrink_hdr:1;   /* This block has at least one shrink header */
 305         u32 seq_number;         /* block sequence number for yaffs2 */
 306
 307 };
 308
 309 /* -------------------------- Object structure -------------------------------*/
 310 /* This is the object structure as stored on NAND */
 311
 312 struct yaffs_obj_hdr {
 313         enum yaffs_obj_type type;
 314
 315         /* Apply to everything  */
 316         int parent_obj_id;
 317         u16 sum_no_longer_used; /* checksum of name. No longer used */
 318         YCHAR name[YAFFS_MAX_NAME_LENGTH + 1];
 319
 320         /* The following apply to all object types except for hard links */
 321         u32 yst_mode;           /* protection */
 322
 323         u32 yst_uid;
 324         u32 yst_gid;
 325         u32 yst_atime;
 326         u32 yst_mtime;
 327         u32 yst_ctime;
 328
 329         /* File size  applies to files only */
 330         u32 file_size_low;
 331
 332         /* Equivalent object id applies to hard links only. */
 333         int equiv_id;
 334
 335         /* Alias is for symlinks only. */
 336         YCHAR alias[YAFFS_MAX_ALIAS_LENGTH + 1];
 337
 338         u32 yst_rdev;   /* stuff for block and char devices (major/min) */
 339
 340         u32 win_ctime[2];
 341         u32 win_atime[2];
 342         u32 win_mtime[2];
 343
 344         u32 inband_shadowed_obj_id;
 345         u32 inband_is_shrink;
 346
 347         u32 file_size_high;
 348         u32 reserved[1];
 349         int shadows_obj;        /* This object header shadows the
 350                                 specified object if > 0 */
 351
 352         /* is_shrink applies to object headers written when wemake a hole. */
 353         u32 is_shrink;
 354
 355 };
 356
 357 /*--------------------------- Tnode -------------------------- */
 358
 359 struct yaffs_tnode {
 360         struct yaffs_tnode *internal[YAFFS_NTNODES_INTERNAL];
 361 };
 362
 363 /*------------------------  Object -----------------------------*/
 364 /* An object can be one of:
 365  * - a directory (no data, has children links
 366  * - a regular file (data.... not prunes :->).
 367  * - a symlink [symbolic link] (the alias).
 368  * - a hard link
 369  */
 370
 371 struct yaffs_file_var {
 372         loff_t file_size;
 373         loff_t scanned_size;
 374         loff_t shrink_size;
 375         int top_level;
 376         struct yaffs_tnode *top;
 377 };
 378
 379 struct yaffs_dir_var {
 380         struct list_head children;      /* list of child links */
 381         struct list_head dirty; /* Entry for list of dirty directories */
 382 };
 383
 384 struct yaffs_symlink_var {
 385         YCHAR *alias;
 386 };
 387
 388 struct yaffs_hardlink_var {
 389         struct yaffs_obj *equiv_obj;
 390         u32 equiv_id;
 391 };
 392
 393 union yaffs_obj_var {
 394         struct yaffs_file_var file_variant;
 395         struct yaffs_dir_var dir_variant;
 396         struct yaffs_symlink_var symlink_variant;
 397         struct yaffs_hardlink_var hardlink_variant;
 398 };
 399
 400 struct yaffs_obj {
 401         u8 deleted:1;           /* This should only apply to unlinked files. */
 402         u8 soft_del:1;          /* it has also been soft deleted */
 403         u8 unlinked:1;          /* An unlinked file.*/
 404         u8 fake:1;              /* A fake object has no presence on NAND. */
 405         u8 rename_allowed:1;    /* Some objects cannot be renamed. */
 406         u8 unlink_allowed:1;
 407         u8 dirty:1;             /* the object needs to be written to flash */
 408         u8 valid:1;             /* When the file system is being loaded up, this
 409                                  * object might be created before the data
 410                                  * is available
 411                                  * ie. file data chunks encountered before
 412                                 * the header.
 413                                  */
 414         u8 lazy_loaded:1;       /* This object has been lazy loaded and
 415                                  * is missing some detail */
 416
 417         u8 defered_free:1;      /* Object is removed from NAND, but is
 418                                  * still in the inode cache.
 419                                  * Free of object is defered.
 420                                  * until the inode is released.
 421                                  */
 422         u8 being_created:1;     /* This object is still being created
 423                                  * so skip some verification checks. */
 424         u8 is_shadowed:1;       /* This object is shadowed on the way
 425                                  * to being renamed. */
 426
 427         u8 xattr_known:1;       /* We know if this has object has xattribs
 428                                  * or not. */
 429         u8 has_xattr:1;         /* This object has xattribs.
 430                                  * Only valid if xattr_known. */
 431
 432         u8 serial;              /* serial number of chunk in NAND.*/
 433         u16 sum;                /* sum of the name to speed searching */
 434
 435         struct yaffs_dev *my_dev;       /* The device I'm on */
 436
 437         struct list_head hash_link;     /* list of objects in hash bucket */
 438
 439         struct list_head hard_links;    /* hard linked object chain*/
 440
 441         /* directory structure stuff */
 442         /* also used for linking up the free list */
 443         struct yaffs_obj *parent;
 444         struct list_head siblings;
 445
 446         /* Where's my object header in NAND? */
 447         int hdr_chunk;
 448
 449         int n_data_chunks;      /* Number of data chunks for this file. */
 450
 451         u32 obj_id;             /* the object id value */
 452
 453         u32 yst_mode;
 454
 455         YCHAR short_name[YAFFS_SHORT_NAME_LENGTH + 1];
 456
 457 #ifdef CONFIG_YAFFS_WINCE
 458         u32 win_ctime[2];
 459         u32 win_mtime[2];
 460         u32 win_atime[2];
 461 #else
 462         u32 yst_uid;
 463         u32 yst_gid;
 464         u32 yst_atime;
 465         u32 yst_mtime;
 466         u32 yst_ctime;
 467 #endif
 468
 469         u32 yst_rdev;
 470
 471         void *my_inode;
 472
 473         enum yaffs_obj_type variant_type;
 474
 475         union yaffs_obj_var variant;
 476
 477 };
 478
 479 struct yaffs_obj_bucket {
 480         struct list_head list;
 481         int count;
 482 };
 483
 484 /* yaffs_checkpt_obj holds the definition of an object as dumped
 485  * by checkpointing.
 486  */
 487
 488 struct yaffs_checkpt_obj {
 489         int struct_type;
 490         u32 obj_id;
 491         u32 parent_id;
 492         int hdr_chunk;
 493         enum yaffs_obj_type variant_type:3;
 494         u8 deleted:1;
 495         u8 soft_del:1;
 496         u8 unlinked:1;
 497         u8 fake:1;
 498         u8 rename_allowed:1;
 499         u8 unlink_allowed:1;
 500         u8 serial;
 501         int n_data_chunks;
 502         loff_t size_or_equiv_obj;
 503 };
 504
 505 /*--------------------- Temporary buffers ----------------
 506  *
 507  * These are chunk-sized working buffers. Each device has a few.
 508  */
 509
 510 struct yaffs_buffer {
 511         u8 *buffer;
 512         int in_use;
 513 };
 514
 515 /*----------------- Device ---------------------------------*/
 516
 517 struct yaffs_param {
 518         const YCHAR *name;
 519
 520         /*
 521          * Entry parameters set up way early. Yaffs sets up the rest.
 522          * The structure should be zeroed out before use so that unused
 523          * and default values are zero.
 524          */
 525
 526         int inband_tags;        /* Use unband tags */
 527         u32 total_bytes_per_chunk;      /* Should be >= 512, does not need to
 528                                          be a power of 2 */
 529         int chunks_per_block;   /* does not need to be a power of 2 */
 530         int spare_bytes_per_chunk;      /* spare area size */
 531         int start_block;        /* Start block we're allowed to use */
 532         int end_block;          /* End block we're allowed to use */
 533         int n_reserved_blocks;  /* Tuneable so that we can reduce
 534                                  * reserved blocks on NOR and RAM. */
 535
 536         int n_caches;           /* If <= 0, then short op caching is disabled,
 537                                  * else the number of short op caches.
 538                                  */
 539         int cache_bypass_aligned; /* If non-zero then bypass the cache for
 540                                    * aligned writes.
 541                                    */
 542
 543         int use_nand_ecc;       /* Flag to decide whether or not to use
 544                                  * NAND driver ECC on data (yaffs1) */
 545         int tags_9bytes;        /* Use 9 byte tags */
 546         int no_tags_ecc;        /* Flag to decide whether or not to do ECC
 547                                  * on packed tags (yaffs2) */
 548
 549         int is_yaffs2;          /* Use yaffs2 mode on this device */
 550
 551         int empty_lost_n_found; /* Auto-empty lost+found directory on mount */
 552
 553         int refresh_period;     /* How often to check for a block refresh */
 554
 555         /* Checkpoint control. Can be set before or after initialisation */
 556         u8 skip_checkpt_rd;
 557         u8 skip_checkpt_wr;
 558
 559         int enable_xattr;       /* Enable xattribs */
 560
 561         int max_objects;        /*
 562                                  * Set to limit the number of objects created.
 563                                  * 0 = no limit.
 564                                 */
 565
 566         /* The remove_obj_fn function must be supplied by OS flavours that
 567          * need it.
 568          * yaffs direct uses it to implement the faster readdir.
 569          * Linux uses it to protect the directory during unlocking.
 570          */
 571         void (*remove_obj_fn) (struct yaffs_obj *obj);
 572
 573         /* Callback to mark the superblock dirty */
 574         void (*sb_dirty_fn) (struct yaffs_dev *dev);
 575
 576         /*  Callback to control garbage collection. */
 577         unsigned (*gc_control_fn) (struct yaffs_dev *dev);
 578
 579         /* Debug control flags. Don't use unless you know what you're doing */
 580         int use_header_file_size;       /* Flag to determine if we should use
 581                                          * file sizes from the header */
 582         int disable_lazy_load;  /* Disable lazy loading on this device */
 583         int wide_tnodes_disabled;       /* Set to disable wide tnodes */
 584         int disable_soft_del;   /* yaffs 1 only: Set to disable the use of
 585                                  * softdeletion. */
 586
 587         int defered_dir_update; /* Set to defer directory updates */
 588
 589 #ifdef CONFIG_YAFFS_AUTO_UNICODE
 590         int auto_unicode;
 591 #endif
 592         int always_check_erased;        /* Force chunk erased check always on */
 593
 594         int disable_summary;
 595         int disable_bad_block_marking;
 596
 597 };
 598
 599 struct yaffs_driver {
 600         int (*drv_write_chunk_fn) (struct yaffs_dev *dev, int nand_chunk,
 601                                    const u8 *data, int data_len,
 602                                    const u8 *oob, int oob_len);
 603         int (*drv_read_chunk_fn) (struct yaffs_dev *dev, int nand_chunk,
 604                                    u8 *data, int data_len,
 605                                    u8 *oob, int oob_len,
 606                                    enum yaffs_ecc_result *ecc_result);
 607         int (*drv_erase_fn) (struct yaffs_dev *dev, int block_no);
 608         int (*drv_mark_bad_fn) (struct yaffs_dev *dev, int block_no);
 609         int (*drv_check_bad_fn) (struct yaffs_dev *dev, int block_no);
 610         int (*drv_initialise_fn) (struct yaffs_dev *dev);
 611         int (*drv_deinitialise_fn) (struct yaffs_dev *dev);
 612 };
 613
 614 struct yaffs_tags_handler {
 615         int (*write_chunk_tags_fn) (struct yaffs_dev *dev,
 616                                     int nand_chunk, const u8 *data,
 617                                     const struct yaffs_ext_tags *tags);
 618         int (*read_chunk_tags_fn) (struct yaffs_dev *dev,
 619                                    int nand_chunk, u8 *data,
 620                                    struct yaffs_ext_tags *tags);
 621
 622         int (*query_block_fn) (struct yaffs_dev *dev, int block_no,
 623                                enum yaffs_block_state *state,
 624                                u32 *seq_number);
 625         int (*mark_bad_fn) (struct yaffs_dev *dev, int block_no);
 626 };
 627
 628 struct yaffs_dev {
 629         struct yaffs_param param;
 630         struct yaffs_driver drv;
 631         struct yaffs_tags_handler tagger;
 632
 633         /* Context storage. Holds extra OS specific data for this device */
 634
 635         void *os_context;
 636         void *driver_context;
 637
 638         struct list_head dev_list;
 639
 640         int ll_init;
 641         /* Runtime parameters. Set up by YAFFS. */
 642         int data_bytes_per_chunk;
 643
 644         /* Non-wide tnode stuff */
 645         u16 chunk_grp_bits;     /* Number of bits that need to be resolved if
 646                                  * the tnodes are not wide enough.
 647                                  */
 648         u16 chunk_grp_size;     /* == 2^^chunk_grp_bits */
 649
 650         /* Stuff to support wide tnodes */
 651         u32 tnode_width;
 652         u32 tnode_mask;
 653         u32 tnode_size;
 654
 655         /* Stuff for figuring out file offset to chunk conversions */
 656         u32 chunk_shift;        /* Shift value */
 657         u32 chunk_div;          /* Divisor after shifting: 1 for 2^n sizes */
 658         u32 chunk_mask;         /* Mask to use for power-of-2 case */
 659
 660         int is_mounted;
 661         int read_only;
 662         int is_checkpointed;
 663
 664         /* Stuff to support block offsetting to support start block zero */
 665         int internal_start_block;
 666         int internal_end_block;
 667         int block_offset;
 668         int chunk_offset;
 669
 670         /* Runtime checkpointing stuff */
 671         int checkpt_page_seq;   /* running sequence number of checkpt pages */
 672         int checkpt_byte_count;
 673         int checkpt_byte_offs;
 674         u8 *checkpt_buffer;
 675         int checkpt_open_write;
 676         int blocks_in_checkpt;
 677         int checkpt_cur_chunk;
 678         int checkpt_cur_block;
 679         int checkpt_next_block;
 680         int *checkpt_block_list;
 681         int checkpt_max_blocks;
 682         u32 checkpt_sum;
 683         u32 checkpt_xor;
 684
 685         int checkpoint_blocks_required; /* Number of blocks needed to store
 686                                          * current checkpoint set */
 687
 688         /* Block Info */
 689         struct yaffs_block_info *block_info;
 690         u8 *chunk_bits;         /* bitmap of chunks in use */
 691         u8 block_info_alt:1;    /* allocated using alternative alloc */
 692         u8 chunk_bits_alt:1;    /* allocated using alternative alloc */
 693         int chunk_bit_stride;   /* Number of bytes of chunk_bits per block.
 694                                  * Must be consistent with chunks_per_block.
 695                                  */
 696
 697         int n_erased_blocks;
 698         int alloc_block;        /* Current block being allocated off */
 699         u32 alloc_page;
 700         int alloc_block_finder; /* Used to search for next allocation block */
 701
 702         /* Object and Tnode memory management */
 703         void *allocator;
 704         int n_obj;
 705         int n_tnodes;
 706
 707         int n_hardlinks;
 708
 709         struct yaffs_obj_bucket obj_bucket[YAFFS_NOBJECT_BUCKETS];
 710         u32 bucket_finder;
 711
 712         int n_free_chunks;
 713
 714         /* Garbage collection control */
 715         u32 *gc_cleanup_list;   /* objects to delete at the end of a GC. */
 716         u32 n_clean_ups;
 717
 718         unsigned has_pending_prioritised_gc;    /* We think this device might
 719                                                 have pending prioritised gcs */
 720         unsigned gc_disable;
 721         unsigned gc_block_finder;
 722         unsigned gc_dirtiest;
 723         unsigned gc_pages_in_use;
 724         unsigned gc_not_done;
 725         unsigned gc_block;
 726         unsigned gc_chunk;
 727         unsigned gc_skip;
 728         struct yaffs_summary_tags *gc_sum_tags;
 729
 730         /* Special directories */
 731         struct yaffs_obj *root_dir;
 732         struct yaffs_obj *lost_n_found;
 733
 734         int buffered_block;     /* Which block is buffered here? */
 735         int doing_buffered_block_rewrite;
 736
 737         struct yaffs_cache *cache;
 738         int cache_last_use;
 739
 740         /* Stuff for background deletion and unlinked files. */
 741         struct yaffs_obj *unlinked_dir; /* Directory where unlinked and deleted
 742                                          files live. */
 743         struct yaffs_obj *del_dir;      /* Directory where deleted objects are
 744                                         sent to disappear. */
 745         struct yaffs_obj *unlinked_deletion;    /* Current file being
 746                                                         background deleted. */
 747         int n_deleted_files;    /* Count of files awaiting deletion; */
 748         int n_unlinked_files;   /* Count of unlinked files. */
 749         int n_bg_deletions;     /* Count of background deletions. */
 750
 751         /* Temporary buffer management */
 752         struct yaffs_buffer temp_buffer[YAFFS_N_TEMP_BUFFERS];
 753         int max_temp;
 754         int temp_in_use;
 755         int unmanaged_buffer_allocs;
 756         int unmanaged_buffer_deallocs;
 757
 758         /* yaffs2 runtime stuff */
 759         unsigned seq_number;    /* Sequence number of currently
 760                                         allocating block */
 761         unsigned oldest_dirty_seq;
 762         unsigned oldest_dirty_block;
 763
 764         /* Block refreshing */
 765         int refresh_skip;       /* A skip down counter.
 766                                  * Refresh happens when this gets to zero. */
 767
 768         /* Dirty directory handling */
 769         struct list_head dirty_dirs;    /* List of dirty directories */
 770
 771         /* Summary */
 772         int chunks_per_summary;
 773         struct yaffs_summary_tags *sum_tags;
 774
 775         /* Statistics */
 776         u32 n_page_writes;
 777         u32 n_page_reads;
 778         u32 n_erasures;
 779         u32 n_bad_queries;
 780         u32 n_bad_markings;
 781         u32 n_erase_failures;
 782         u32 n_gc_copies;
 783         u32 all_gcs;
 784         u32 passive_gc_count;
 785         u32 oldest_dirty_gc_count;
 786         u32 n_gc_blocks;
 787         u32 bg_gcs;
 788         u32 n_retried_writes;
 789         u32 n_retired_blocks;
 790         u32 n_ecc_fixed;
 791         u32 n_ecc_unfixed;
 792         u32 n_tags_ecc_fixed;
 793         u32 n_tags_ecc_unfixed;
 794         u32 n_deletions;
 795         u32 n_unmarked_deletions;
 796         u32 refresh_count;
 797         u32 cache_hits;
 798         u32 tags_used;
 799         u32 summary_used;
 800
 801 };
 802
 803 /* The CheckpointDevice structure holds the device information that changes
 804  *at runtime and must be preserved over unmount/mount cycles.
 805  */
 806 struct yaffs_checkpt_dev {
 807         int struct_type;
 808         int n_erased_blocks;
 809         int alloc_block;        /* Current block being allocated off */
 810         u32 alloc_page;
 811         int n_free_chunks;
 812
 813         int n_deleted_files;    /* Count of files awaiting deletion; */
 814         int n_unlinked_files;   /* Count of unlinked files. */
 815         int n_bg_deletions;     /* Count of background deletions. */
 816
 817         /* yaffs2 runtime stuff */
 818         unsigned seq_number;    /* Sequence number of currently
 819                                  * allocating block */
 820
 821 };
 822
 823 struct yaffs_checkpt_validity {
 824         int struct_type;
 825         u32 magic;
 826         u32 version;
 827         u32 head;
 828 };
 829
 830 struct yaffs_shadow_fixer {
 831         int obj_id;
 832         int shadowed_id;
 833         struct yaffs_shadow_fixer *next;
 834 };
 835
 836 /* Structure for doing xattr modifications */
 837 struct yaffs_xattr_mod {
 838         int set;                /* If 0 then this is a deletion */
 839         const YCHAR *name;
 840         const void *data;
 841         int size;
 842         int flags;
 843         int result;
 844 };
 845
 846 /*----------------------- YAFFS Functions -----------------------*/
 847
 848 int yaffs_guts_initialise(struct yaffs_dev *dev);
 849 void yaffs_deinitialise(struct yaffs_dev *dev);
 850
 851 int yaffs_get_n_free_chunks(struct yaffs_dev *dev);
 852
 853 int yaffs_rename_obj(struct yaffs_obj *old_dir, const YCHAR * old_name,
 854                      struct yaffs_obj *new_dir, const YCHAR * new_name);
 855
 856 int yaffs_unlinker(struct yaffs_obj *dir, const YCHAR * name);
 857 int yaffs_del_obj(struct yaffs_obj *obj);
 858 struct yaffs_obj *yaffs_retype_obj(struct yaffs_obj *obj,
 859                                    enum yaffs_obj_type type);
 860
 861
 862 int yaffs_get_obj_name(struct yaffs_obj *obj, YCHAR * name, int buffer_size);
 863 loff_t yaffs_get_obj_length(struct yaffs_obj *obj);
 864 int yaffs_get_obj_inode(struct yaffs_obj *obj);
 865 unsigned yaffs_get_obj_type(struct yaffs_obj *obj);
 866 int yaffs_get_obj_link_count(struct yaffs_obj *obj);
 867
 868 /* File operations */
 869 int yaffs_file_rd(struct yaffs_obj *obj, u8 * buffer, loff_t offset,
 870                   int n_bytes);
 871 int yaffs_wr_file(struct yaffs_obj *obj, const u8 * buffer, loff_t offset,
 872                   int n_bytes, int write_trhrough);
 873 int yaffs_resize_file(struct yaffs_obj *obj, loff_t new_size);
 874
 875 struct yaffs_obj *yaffs_create_file(struct yaffs_obj *parent,
 876                                     const YCHAR *name, u32 mode, u32 uid,
 877                                     u32 gid);
 878
 879 int yaffs_flush_file(struct yaffs_obj *in,
 880                      int update_time,
 881                      int data_sync,
 882                      int discard_cache);
 883
 884 /* Flushing and checkpointing */
 885 void yaffs_flush_whole_cache(struct yaffs_dev *dev, int discard);
 886
 887 int yaffs_checkpoint_save(struct yaffs_dev *dev);
 888 int yaffs_checkpoint_restore(struct yaffs_dev *dev);
 889
 890 /* Directory operations */
 891 struct yaffs_obj *yaffs_create_dir(struct yaffs_obj *parent, const YCHAR *name,
 892                                    u32 mode, u32 uid, u32 gid);
 893 struct yaffs_obj *yaffs_find_by_name(struct yaffs_obj *the_dir,
 894                                      const YCHAR *name);
 895 struct yaffs_obj *yaffs_find_by_number(struct yaffs_dev *dev, u32 number);
 896
 897 /* Link operations */
 898 struct yaffs_obj *yaffs_link_obj(struct yaffs_obj *parent, const YCHAR *name,
 899                                  struct yaffs_obj *equiv_obj);
 900
 901 struct yaffs_obj *yaffs_get_equivalent_obj(struct yaffs_obj *obj);
 902
 903 /* Symlink operations */
 904 struct yaffs_obj *yaffs_create_symlink(struct yaffs_obj *parent,
 905                                        const YCHAR *name, u32 mode, u32 uid,
 906                                        u32 gid, const YCHAR *alias);
 907 YCHAR *yaffs_get_symlink_alias(struct yaffs_obj *obj);
 908
 909 /* Special inodes (fifos, sockets and devices) */
 910 struct yaffs_obj *yaffs_create_special(struct yaffs_obj *parent,
 911                                        const YCHAR *name, u32 mode, u32 uid,
 912                                        u32 gid, u32 rdev);
 913
 914 int yaffs_set_xattrib(struct yaffs_obj *obj, const YCHAR *name,
 915                       const void *value, int size, int flags);
 916 int yaffs_get_xattrib(struct yaffs_obj *obj, const YCHAR *name, void *value,
 917                       int size);
 918 int yaffs_list_xattrib(struct yaffs_obj *obj, char *buffer, int size);
 919 int yaffs_remove_xattrib(struct yaffs_obj *obj, const YCHAR *name);
 920
 921 /* Special directories */
 922 struct yaffs_obj *yaffs_root(struct yaffs_dev *dev);
 923 struct yaffs_obj *yaffs_lost_n_found(struct yaffs_dev *dev);
 924
 925 void yaffs_handle_defered_free(struct yaffs_obj *obj);
 926
 927 void yaffs_update_dirty_dirs(struct yaffs_dev *dev);
 928
 929 int yaffs_bg_gc(struct yaffs_dev *dev, unsigned urgency);
 930
 931 /* Debug dump  */
 932 int yaffs_dump_obj(struct yaffs_obj *obj);
 933
 934 void yaffs_guts_test(struct yaffs_dev *dev);
 935 int yaffs_guts_ll_init(struct yaffs_dev *dev);
 936
 937
 938 /* A few useful functions to be used within the core files*/
 939 void yaffs_chunk_del(struct yaffs_dev *dev, int chunk_id, int mark_flash,
 940                      int lyn);
 941 int yaffs_check_ff(u8 *buffer, int n_bytes);
 942 void yaffs_handle_chunk_error(struct yaffs_dev *dev,
 943                               struct yaffs_block_info *bi);
 944
 945 u8 *yaffs_get_temp_buffer(struct yaffs_dev *dev);
 946 void yaffs_release_temp_buffer(struct yaffs_dev *dev, u8 *buffer);
 947
 948 struct yaffs_obj *yaffs_find_or_create_by_number(struct yaffs_dev *dev,
 949                                                  int number,
 950                                                  enum yaffs_obj_type type);
 951 int yaffs_put_chunk_in_file(struct yaffs_obj *in, int inode_chunk,
 952                             int nand_chunk, int in_scan);
 953 void yaffs_set_obj_name(struct yaffs_obj *obj, const YCHAR *name);
 954 void yaffs_set_obj_name_from_oh(struct yaffs_obj *obj,
 955                                 const struct yaffs_obj_hdr *oh);
 956 void yaffs_add_obj_to_dir(struct yaffs_obj *directory, struct yaffs_obj *obj);
 957 YCHAR *yaffs_clone_str(const YCHAR *str);
 958 void yaffs_link_fixup(struct yaffs_dev *dev, struct list_head *hard_list);
 959 void yaffs_block_became_dirty(struct yaffs_dev *dev, int block_no);
 960 int yaffs_update_oh(struct yaffs_obj *in, const YCHAR *name,
 961                     int force, int is_shrink, int shadows,
 962                     struct yaffs_xattr_mod *xop);
 963 void yaffs_handle_shadowed_obj(struct yaffs_dev *dev, int obj_id,
 964                                int backward_scanning);
 965 int yaffs_check_alloc_available(struct yaffs_dev *dev, int n_chunks);
 966 struct yaffs_tnode *yaffs_get_tnode(struct yaffs_dev *dev);
 967 struct yaffs_tnode *yaffs_add_find_tnode_0(struct yaffs_dev *dev,
 968                                            struct yaffs_file_var *file_struct,
 969                                            u32 chunk_id,
 970                                            struct yaffs_tnode *passed_tn);
 971
 972 int yaffs_do_file_wr(struct yaffs_obj *in, const u8 *buffer, loff_t offset,
 973                      int n_bytes, int write_trhrough);
 974 void yaffs_resize_file_down(struct yaffs_obj *obj, loff_t new_size);
 975 void yaffs_skip_rest_of_block(struct yaffs_dev *dev);
 976
 977 int yaffs_count_free_chunks(struct yaffs_dev *dev);
 978
 979 struct yaffs_tnode *yaffs_find_tnode_0(struct yaffs_dev *dev,
 980                                        struct yaffs_file_var *file_struct,
 981                                        u32 chunk_id);
 982
 983 u32 yaffs_get_group_base(struct yaffs_dev *dev, struct yaffs_tnode *tn,
 984                          unsigned pos);
 985
 986 int yaffs_is_non_empty_dir(struct yaffs_obj *obj);
 987
 988 int yaffs_guts_format_dev(struct yaffs_dev *dev);
 989
 990 void yaffs_addr_to_chunk(struct yaffs_dev *dev, loff_t addr,
 991                                 int *chunk_out, u32 *offset_out);
 992 /*
 993  * Marshalling functions to get loff_t file sizes into aand out of
 994  * object headers.
 995  */
 996 void yaffs_oh_size_load(struct yaffs_obj_hdr *oh, loff_t fsize);
 997 loff_t yaffs_oh_to_size(struct yaffs_obj_hdr *oh);
 998 loff_t yaffs_max_file_size(struct yaffs_dev *dev);
 999
1000 /*
1001  * Debug function to count number of blocks in each state
1002  * NB Needs to be called with correct number of integers
1003  */
1004
1005 void yaffs_count_blocks_by_state(struct yaffs_dev *dev, int bs[10]);
1006
1007 int yaffs_find_chunk_in_file(struct yaffs_obj *in, int inode_chunk,
1008                                     struct yaffs_ext_tags *tags);
1009
1010 #endif