LXR linux/fs/xfs/libxfs/xfs

   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Copyright (c) 2000-2001,2005 Silicon Graphics, Inc.
   4 * All Rights Reserved.
   5 */
   6#ifndef __XFS_BTREE_H__
   7#define __XFS_BTREE_H__
   8
   9struct xfs_buf;
  10struct xfs_inode;
  11struct xfs_mount;
  12struct xfs_trans;
  13
  14extern kmem_zone_t      *xfs_btree_cur_zone;
  15
  16/*
  17 * Generic key, ptr and record wrapper structures.
  18 *
  19 * These are disk format structures, and are converted where necessary
  20 * by the btree specific code that needs to interpret them.
  21 */
  22union xfs_btree_ptr {
  23        __be32                  s;      /* short form ptr */
  24        __be64                  l;      /* long form ptr */
  25};
  26
  27/*
  28 * The in-core btree key.  Overlapping btrees actually store two keys
  29 * per pointer, so we reserve enough memory to hold both.  The __*bigkey
  30 * items should never be accessed directly.
  31 */
  32union xfs_btree_key {
  33        struct xfs_bmbt_key             bmbt;
  34        xfs_bmdr_key_t                  bmbr;   /* bmbt root block */
  35        xfs_alloc_key_t                 alloc;
  36        struct xfs_inobt_key            inobt;
  37        struct xfs_rmap_key             rmap;
  38        struct xfs_rmap_key             __rmap_bigkey[2];
  39        struct xfs_refcount_key         refc;
  40};
  41
  42union xfs_btree_rec {
  43        struct xfs_bmbt_rec             bmbt;
  44        xfs_bmdr_rec_t                  bmbr;   /* bmbt root block */
  45        struct xfs_alloc_rec            alloc;
  46        struct xfs_inobt_rec            inobt;
  47        struct xfs_rmap_rec             rmap;
  48        struct xfs_refcount_rec         refc;
  49};
  50
  51/*
  52 * This nonsense is to make -wlint happy.
  53 */
  54#define XFS_LOOKUP_EQ   ((xfs_lookup_t)XFS_LOOKUP_EQi)
  55#define XFS_LOOKUP_LE   ((xfs_lookup_t)XFS_LOOKUP_LEi)
  56#define XFS_LOOKUP_GE   ((xfs_lookup_t)XFS_LOOKUP_GEi)
  57
  58#define XFS_BTNUM_BNO   ((xfs_btnum_t)XFS_BTNUM_BNOi)
  59#define XFS_BTNUM_CNT   ((xfs_btnum_t)XFS_BTNUM_CNTi)
  60#define XFS_BTNUM_BMAP  ((xfs_btnum_t)XFS_BTNUM_BMAPi)
  61#define XFS_BTNUM_INO   ((xfs_btnum_t)XFS_BTNUM_INOi)
  62#define XFS_BTNUM_FINO  ((xfs_btnum_t)XFS_BTNUM_FINOi)
  63#define XFS_BTNUM_RMAP  ((xfs_btnum_t)XFS_BTNUM_RMAPi)
  64#define XFS_BTNUM_REFC  ((xfs_btnum_t)XFS_BTNUM_REFCi)
  65
  66uint32_t xfs_btree_magic(int crc, xfs_btnum_t btnum);
  67
  68/*
  69 * For logging record fields.
  70 */
  71#define XFS_BB_MAGIC            (1 << 0)
  72#define XFS_BB_LEVEL            (1 << 1)
  73#define XFS_BB_NUMRECS          (1 << 2)
  74#define XFS_BB_LEFTSIB          (1 << 3)
  75#define XFS_BB_RIGHTSIB         (1 << 4)
  76#define XFS_BB_BLKNO            (1 << 5)
  77#define XFS_BB_LSN              (1 << 6)
  78#define XFS_BB_UUID             (1 << 7)
  79#define XFS_BB_OWNER            (1 << 8)
  80#define XFS_BB_NUM_BITS         5
  81#define XFS_BB_ALL_BITS         ((1 << XFS_BB_NUM_BITS) - 1)
  82#define XFS_BB_NUM_BITS_CRC     9
  83#define XFS_BB_ALL_BITS_CRC     ((1 << XFS_BB_NUM_BITS_CRC) - 1)
  84
  85/*
  86 * Generic stats interface
  87 */
  88#define XFS_BTREE_STATS_INC(cur, stat)  \
  89        XFS_STATS_INC_OFF((cur)->bc_mp, (cur)->bc_statoff + __XBTS_ ## stat)
  90#define XFS_BTREE_STATS_ADD(cur, stat, val)     \
  91        XFS_STATS_ADD_OFF((cur)->bc_mp, (cur)->bc_statoff + __XBTS_ ## stat, val)
  92
  93#define XFS_BTREE_MAXLEVELS     9       /* max of all btrees */
  94
  95struct xfs_btree_ops {
  96        /* size of the key and record structures */
  97        size_t  key_len;
  98        size_t  rec_len;
  99
 100        /* cursor operations */
 101        struct xfs_btree_cur *(*dup_cursor)(struct xfs_btree_cur *);
 102        void    (*update_cursor)(struct xfs_btree_cur *src,
 103                                 struct xfs_btree_cur *dst);
 104
 105        /* update btree root pointer */
 106        void    (*set_root)(struct xfs_btree_cur *cur,
 107                            union xfs_btree_ptr *nptr, int level_change);
 108
 109        /* block allocation / freeing */
 110        int     (*alloc_block)(struct xfs_btree_cur *cur,
 111                               union xfs_btree_ptr *start_bno,
 112                               union xfs_btree_ptr *new_bno,
 113                               int *stat);
 114        int     (*free_block)(struct xfs_btree_cur *cur, struct xfs_buf *bp);
 115
 116        /* update last record information */
 117        void    (*update_lastrec)(struct xfs_btree_cur *cur,
 118                                  struct xfs_btree_block *block,
 119                                  union xfs_btree_rec *rec,
 120                                  int ptr, int reason);
 121
 122        /* records in block/level */
 123        int     (*get_minrecs)(struct xfs_btree_cur *cur, int level);
 124        int     (*get_maxrecs)(struct xfs_btree_cur *cur, int level);
 125
 126        /* records on disk.  Matter for the root in inode case. */
 127        int     (*get_dmaxrecs)(struct xfs_btree_cur *cur, int level);
 128
 129        /* init values of btree structures */
 130        void    (*init_key_from_rec)(union xfs_btree_key *key,
 131                                     union xfs_btree_rec *rec);
 132        void    (*init_rec_from_cur)(struct xfs_btree_cur *cur,
 133                                     union xfs_btree_rec *rec);
 134        void    (*init_ptr_from_cur)(struct xfs_btree_cur *cur,
 135                                     union xfs_btree_ptr *ptr);
 136        void    (*init_high_key_from_rec)(union xfs_btree_key *key,
 137                                          union xfs_btree_rec *rec);
 138
 139        /* difference between key value and cursor value */
 140        int64_t (*key_diff)(struct xfs_btree_cur *cur,
 141                              union xfs_btree_key *key);
 142
 143        /*
 144         * Difference between key2 and key1 -- positive if key1 > key2,
 145         * negative if key1 < key2, and zero if equal.
 146         */
 147        int64_t (*diff_two_keys)(struct xfs_btree_cur *cur,
 148                                   union xfs_btree_key *key1,
 149                                   union xfs_btree_key *key2);
 150
 151        const struct xfs_buf_ops        *buf_ops;
 152
 153        /* check that k1 is lower than k2 */
 154        int     (*keys_inorder)(struct xfs_btree_cur *cur,
 155                                union xfs_btree_key *k1,
 156                                union xfs_btree_key *k2);
 157
 158        /* check that r1 is lower than r2 */
 159        int     (*recs_inorder)(struct xfs_btree_cur *cur,
 160                                union xfs_btree_rec *r1,
 161                                union xfs_btree_rec *r2);
 162};
 163
 164/*
 165 * Reasons for the update_lastrec method to be called.
 166 */
 167#define LASTREC_UPDATE  0
 168#define LASTREC_INSREC  1
 169#define LASTREC_DELREC  2
 170
 171
 172union xfs_btree_irec {
 173        struct xfs_alloc_rec_incore     a;
 174        struct xfs_bmbt_irec            b;
 175        struct xfs_inobt_rec_incore     i;
 176        struct xfs_rmap_irec            r;
 177        struct xfs_refcount_irec        rc;
 178};
 179
 180/* Per-AG btree private information. */
 181union xfs_btree_cur_private {
 182        struct {
 183                unsigned long   nr_ops;         /* # record updates */
 184                int             shape_changes;  /* # of extent splits */
 185        } refc;
 186};
 187
 188/*
 189 * Btree cursor structure.
 190 * This collects all information needed by the btree code in one place.
 191 */
 192typedef struct xfs_btree_cur
 193{
 194        struct xfs_trans        *bc_tp; /* transaction we're in, if any */
 195        struct xfs_mount        *bc_mp; /* file system mount struct */
 196        const struct xfs_btree_ops *bc_ops;
 197        uint                    bc_flags; /* btree features - below */
 198        union xfs_btree_irec    bc_rec; /* current insert/search record value */
 199        struct xfs_buf  *bc_bufs[XFS_BTREE_MAXLEVELS];  /* buf ptr per level */
 200        int             bc_ptrs[XFS_BTREE_MAXLEVELS];   /* key/record # */
 201        uint8_t         bc_ra[XFS_BTREE_MAXLEVELS];     /* readahead bits */
 202#define XFS_BTCUR_LEFTRA        1       /* left sibling has been read-ahead */
 203#define XFS_BTCUR_RIGHTRA       2       /* right sibling has been read-ahead */
 204        uint8_t         bc_nlevels;     /* number of levels in the tree */
 205        uint8_t         bc_blocklog;    /* log2(blocksize) of btree blocks */
 206        xfs_btnum_t     bc_btnum;       /* identifies which btree type */
 207        int             bc_statoff;     /* offset of btre stats array */
 208        union {
 209                struct {                        /* needed for BNO, CNT, INO */
 210                        struct xfs_buf  *agbp;  /* agf/agi buffer pointer */
 211                        xfs_agnumber_t  agno;   /* ag number */
 212                        union xfs_btree_cur_private     priv;
 213                } a;
 214                struct {                        /* needed for BMAP */
 215                        struct xfs_inode *ip;   /* pointer to our inode */
 216                        int             allocated;      /* count of alloced */
 217                        short           forksize;       /* fork's inode space */
 218                        char            whichfork;      /* data or attr fork */
 219                        char            flags;          /* flags */
 220#define XFS_BTCUR_BPRV_WASDEL           (1<<0)          /* was delayed */
 221#define XFS_BTCUR_BPRV_INVALID_OWNER    (1<<1)          /* for ext swap */
 222                } b;
 223        }               bc_private;     /* per-btree type data */
 224} xfs_btree_cur_t;
 225
 226/* cursor flags */
 227#define XFS_BTREE_LONG_PTRS             (1<<0)  /* pointers are 64bits long */
 228#define XFS_BTREE_ROOT_IN_INODE         (1<<1)  /* root may be variable size */
 229#define XFS_BTREE_LASTREC_UPDATE        (1<<2)  /* track last rec externally */
 230#define XFS_BTREE_CRC_BLOCKS            (1<<3)  /* uses extended btree blocks */
 231#define XFS_BTREE_OVERLAPPING           (1<<4)  /* overlapping intervals */
 232
 233
 234#define XFS_BTREE_NOERROR       0
 235#define XFS_BTREE_ERROR         1
 236
 237/*
 238 * Convert from buffer to btree block header.
 239 */
 240#define XFS_BUF_TO_BLOCK(bp)    ((struct xfs_btree_block *)((bp)->b_addr))
 241
 242/*
 243 * Internal long and short btree block checks.  They return NULL if the
 244 * block is ok or the address of the failed check otherwise.
 245 */
 246xfs_failaddr_t __xfs_btree_check_lblock(struct xfs_btree_cur *cur,
 247                struct xfs_btree_block *block, int level, struct xfs_buf *bp);
 248xfs_failaddr_t __xfs_btree_check_sblock(struct xfs_btree_cur *cur,
 249                struct xfs_btree_block *block, int level, struct xfs_buf *bp);
 250
 251/*
 252 * Check that block header is ok.
 253 */
 254int
 255xfs_btree_check_block(
 256        struct xfs_btree_cur    *cur,   /* btree cursor */
 257        struct xfs_btree_block  *block, /* generic btree block pointer */
 258        int                     level,  /* level of the btree block */
 259        struct xfs_buf          *bp);   /* buffer containing block, if any */
 260
 261/*
 262 * Check that (long) pointer is ok.
 263 */
 264bool                                    /* error (0 or EFSCORRUPTED) */
 265xfs_btree_check_lptr(
 266        struct xfs_btree_cur    *cur,   /* btree cursor */
 267        xfs_fsblock_t           fsbno,  /* btree block disk address */
 268        int                     level); /* btree block level */
 269
 270/*
 271 * Check that (short) pointer is ok.
 272 */
 273bool                                    /* error (0 or EFSCORRUPTED) */
 274xfs_btree_check_sptr(
 275        struct xfs_btree_cur    *cur,   /* btree cursor */
 276        xfs_agblock_t           agbno,  /* btree block disk address */
 277        int                     level); /* btree block level */
 278
 279/*
 280 * Delete the btree cursor.
 281 */
 282void
 283xfs_btree_del_cursor(
 284        xfs_btree_cur_t         *cur,   /* btree cursor */
 285        int                     error); /* del because of error */
 286
 287/*
 288 * Duplicate the btree cursor.
 289 * Allocate a new one, copy the record, re-get the buffers.
 290 */
 291int                                     /* error */
 292xfs_btree_dup_cursor(
 293        xfs_btree_cur_t         *cur,   /* input cursor */
 294        xfs_btree_cur_t         **ncur);/* output cursor */
 295
 296/*
 297 * Get a buffer for the block, return it with no data read.
 298 * Long-form addressing.
 299 */
 300struct xfs_buf *                                /* buffer for fsbno */
 301xfs_btree_get_bufl(
 302        struct xfs_mount        *mp,    /* file system mount point */
 303        struct xfs_trans        *tp,    /* transaction pointer */
 304        xfs_fsblock_t           fsbno); /* file system block number */
 305
 306/*
 307 * Get a buffer for the block, return it with no data read.
 308 * Short-form addressing.
 309 */
 310struct xfs_buf *                                /* buffer for agno/agbno */
 311xfs_btree_get_bufs(
 312        struct xfs_mount        *mp,    /* file system mount point */
 313        struct xfs_trans        *tp,    /* transaction pointer */
 314        xfs_agnumber_t          agno,   /* allocation group number */
 315        xfs_agblock_t           agbno); /* allocation group block number */
 316
 317/*
 318 * Check for the cursor referring to the last block at the given level.
 319 */
 320int                                     /* 1=is last block, 0=not last block */
 321xfs_btree_islastblock(
 322        xfs_btree_cur_t         *cur,   /* btree cursor */
 323        int                     level); /* level to check */
 324
 325/*
 326 * Compute first and last byte offsets for the fields given.
 327 * Interprets the offsets table, which contains struct field offsets.
 328 */
 329void
 330xfs_btree_offsets(
 331        int64_t                 fields, /* bitmask of fields */
 332        const short             *offsets,/* table of field offsets */
 333        int                     nbits,  /* number of bits to inspect */
 334        int                     *first, /* output: first byte offset */
 335        int                     *last); /* output: last byte offset */
 336
 337/*
 338 * Get a buffer for the block, return it read in.
 339 * Long-form addressing.
 340 */
 341int                                     /* error */
 342xfs_btree_read_bufl(
 343        struct xfs_mount        *mp,    /* file system mount point */
 344        struct xfs_trans        *tp,    /* transaction pointer */
 345        xfs_fsblock_t           fsbno,  /* file system block number */
 346        struct xfs_buf          **bpp,  /* buffer for fsbno */
 347        int                     refval, /* ref count value for buffer */
 348        const struct xfs_buf_ops *ops);
 349
 350/*
 351 * Read-ahead the block, don't wait for it, don't return a buffer.
 352 * Long-form addressing.
 353 */
 354void                                    /* error */
 355xfs_btree_reada_bufl(
 356        struct xfs_mount        *mp,    /* file system mount point */
 357        xfs_fsblock_t           fsbno,  /* file system block number */
 358        xfs_extlen_t            count,  /* count of filesystem blocks */
 359        const struct xfs_buf_ops *ops);
 360
 361/*
 362 * Read-ahead the block, don't wait for it, don't return a buffer.
 363 * Short-form addressing.
 364 */
 365void                                    /* error */
 366xfs_btree_reada_bufs(
 367        struct xfs_mount        *mp,    /* file system mount point */
 368        xfs_agnumber_t          agno,   /* allocation group number */
 369        xfs_agblock_t           agbno,  /* allocation group block number */
 370        xfs_extlen_t            count,  /* count of filesystem blocks */
 371        const struct xfs_buf_ops *ops);
 372
 373/*
 374 * Initialise a new btree block header
 375 */
 376void
 377xfs_btree_init_block(
 378        struct xfs_mount *mp,
 379        struct xfs_buf  *bp,
 380        xfs_btnum_t     btnum,
 381        __u16           level,
 382        __u16           numrecs,
 383        __u64           owner);
 384
 385void
 386xfs_btree_init_block_int(
 387        struct xfs_mount        *mp,
 388        struct xfs_btree_block  *buf,
 389        xfs_daddr_t             blkno,
 390        xfs_btnum_t             btnum,
 391        __u16                   level,
 392        __u16                   numrecs,
 393        __u64                   owner,
 394        unsigned int            flags);
 395
 396/*
 397 * Common btree core entry points.
 398 */
 399int xfs_btree_increment(struct xfs_btree_cur *, int, int *);
 400int xfs_btree_decrement(struct xfs_btree_cur *, int, int *);
 401int xfs_btree_lookup(struct xfs_btree_cur *, xfs_lookup_t, int *);
 402int xfs_btree_update(struct xfs_btree_cur *, union xfs_btree_rec *);
 403int xfs_btree_new_iroot(struct xfs_btree_cur *, int *, int *);
 404int xfs_btree_insert(struct xfs_btree_cur *, int *);
 405int xfs_btree_delete(struct xfs_btree_cur *, int *);
 406int xfs_btree_get_rec(struct xfs_btree_cur *, union xfs_btree_rec **, int *);
 407int xfs_btree_change_owner(struct xfs_btree_cur *cur, uint64_t new_owner,
 408                           struct list_head *buffer_list);
 409
 410/*
 411 * btree block CRC helpers
 412 */
 413void xfs_btree_lblock_calc_crc(struct xfs_buf *);
 414bool xfs_btree_lblock_verify_crc(struct xfs_buf *);
 415void xfs_btree_sblock_calc_crc(struct xfs_buf *);
 416bool xfs_btree_sblock_verify_crc(struct xfs_buf *);
 417
 418/*
 419 * Internal btree helpers also used by xfs_bmap.c.
 420 */
 421void xfs_btree_log_block(struct xfs_btree_cur *, struct xfs_buf *, int);
 422void xfs_btree_log_recs(struct xfs_btree_cur *, struct xfs_buf *, int, int);
 423
 424/*
 425 * Helpers.
 426 */
 427static inline int xfs_btree_get_numrecs(struct xfs_btree_block *block)
 428{
 429        return be16_to_cpu(block->bb_numrecs);
 430}
 431
 432static inline void xfs_btree_set_numrecs(struct xfs_btree_block *block,
 433                uint16_t numrecs)
 434{
 435        block->bb_numrecs = cpu_to_be16(numrecs);
 436}
 437
 438static inline int xfs_btree_get_level(struct xfs_btree_block *block)
 439{
 440        return be16_to_cpu(block->bb_level);
 441}
 442
 443
 444/*
 445 * Min and max functions for extlen, agblock, fileoff, and filblks types.
 446 */
 447#define XFS_EXTLEN_MIN(a,b)     min_t(xfs_extlen_t, (a), (b))
 448#define XFS_EXTLEN_MAX(a,b)     max_t(xfs_extlen_t, (a), (b))
 449#define XFS_AGBLOCK_MIN(a,b)    min_t(xfs_agblock_t, (a), (b))
 450#define XFS_AGBLOCK_MAX(a,b)    max_t(xfs_agblock_t, (a), (b))
 451#define XFS_FILEOFF_MIN(a,b)    min_t(xfs_fileoff_t, (a), (b))
 452#define XFS_FILEOFF_MAX(a,b)    max_t(xfs_fileoff_t, (a), (b))
 453#define XFS_FILBLKS_MIN(a,b)    min_t(xfs_filblks_t, (a), (b))
 454#define XFS_FILBLKS_MAX(a,b)    max_t(xfs_filblks_t, (a), (b))
 455
 456xfs_failaddr_t xfs_btree_sblock_v5hdr_verify(struct xfs_buf *bp);
 457xfs_failaddr_t xfs_btree_sblock_verify(struct xfs_buf *bp,
 458                unsigned int max_recs);
 459xfs_failaddr_t xfs_btree_lblock_v5hdr_verify(struct xfs_buf *bp,
 460                uint64_t owner);
 461xfs_failaddr_t xfs_btree_lblock_verify(struct xfs_buf *bp,
 462                unsigned int max_recs);
 463
 464uint xfs_btree_compute_maxlevels(uint *limits, unsigned long len);
 465unsigned long long xfs_btree_calc_size(uint *limits, unsigned long long len);
 466
 467/* return codes */
 468#define XFS_BTREE_QUERY_RANGE_CONTINUE  (XFS_ITER_CONTINUE) /* keep iterating */
 469#define XFS_BTREE_QUERY_RANGE_ABORT     (XFS_ITER_ABORT)    /* stop iterating */
 470typedef int (*xfs_btree_query_range_fn)(struct xfs_btree_cur *cur,
 471                union xfs_btree_rec *rec, void *priv);
 472
 473int xfs_btree_query_range(struct xfs_btree_cur *cur,
 474                union xfs_btree_irec *low_rec, union xfs_btree_irec *high_rec,
 475                xfs_btree_query_range_fn fn, void *priv);
 476int xfs_btree_query_all(struct xfs_btree_cur *cur, xfs_btree_query_range_fn fn,
 477                void *priv);
 478
 479typedef int (*xfs_btree_visit_blocks_fn)(struct xfs_btree_cur *cur, int level,
 480                void *data);
 481int xfs_btree_visit_blocks(struct xfs_btree_cur *cur,
 482                xfs_btree_visit_blocks_fn fn, void *data);
 483
 484int xfs_btree_count_blocks(struct xfs_btree_cur *cur, xfs_extlen_t *blocks);
 485
 486union xfs_btree_rec *xfs_btree_rec_addr(struct xfs_btree_cur *cur, int n,
 487                struct xfs_btree_block *block);
 488union xfs_btree_key *xfs_btree_key_addr(struct xfs_btree_cur *cur, int n,
 489                struct xfs_btree_block *block);
 490union xfs_btree_key *xfs_btree_high_key_addr(struct xfs_btree_cur *cur, int n,
 491                struct xfs_btree_block *block);
 492union xfs_btree_ptr *xfs_btree_ptr_addr(struct xfs_btree_cur *cur, int n,
 493                struct xfs_btree_block *block);
 494int xfs_btree_lookup_get_block(struct xfs_btree_cur *cur, int level,
 495                union xfs_btree_ptr *pp, struct xfs_btree_block **blkp);
 496struct xfs_btree_block *xfs_btree_get_block(struct xfs_btree_cur *cur,
 497                int level, struct xfs_buf **bpp);
 498bool xfs_btree_ptr_is_null(struct xfs_btree_cur *cur, union xfs_btree_ptr *ptr);
 499int64_t xfs_btree_diff_two_ptrs(struct xfs_btree_cur *cur,
 500                                const union xfs_btree_ptr *a,
 501                                const union xfs_btree_ptr *b);
 502void xfs_btree_get_sibling(struct xfs_btree_cur *cur,
 503                           struct xfs_btree_block *block,
 504                           union xfs_btree_ptr *ptr, int lr);
 505void xfs_btree_get_keys(struct xfs_btree_cur *cur,
 506                struct xfs_btree_block *block, union xfs_btree_key *key);
 507union xfs_btree_key *xfs_btree_high_key_from_key(struct xfs_btree_cur *cur,
 508                union xfs_btree_key *key);
 509int xfs_btree_has_record(struct xfs_btree_cur *cur, union xfs_btree_irec *low,
 510                union xfs_btree_irec *high, bool *exists);
 511bool xfs_btree_has_more_records(struct xfs_btree_cur *cur);
 512
 513#endif  /* __XFS_BTREE_H__ */
 514