LXR linux/fs/xfs/xfs_ialloc

   1/*
   2 * Copyright (c) 2000,2005 Silicon Graphics, Inc.
   3 * All Rights Reserved.
   4 *
   5 * This program is free software; you can redistribute it and/or
   6 * modify it under the terms of the GNU General Public License as
   7 * published by the Free Software Foundation.
   8 *
   9 * This program is distributed in the hope that it would be useful,
  10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 * GNU General Public License for more details.
  13 *
  14 * You should have received a copy of the GNU General Public License
  15 * along with this program; if not, write the Free Software Foundation,
  16 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  17 */
  18#ifndef __XFS_IALLOC_BTREE_H__
  19#define __XFS_IALLOC_BTREE_H__
  20
  21/*
  22 * Inode map on-disk structures
  23 */
  24
  25struct xfs_buf;
  26struct xfs_btree_cur;
  27struct xfs_btree_sblock;
  28struct xfs_mount;
  29
  30/*
  31 * There is a btree for the inode map per allocation group.
  32 */
  33#define XFS_IBT_MAGIC   0x49414254      /* 'IABT' */
  34
  35typedef __uint64_t      xfs_inofree_t;
  36#define XFS_INODES_PER_CHUNK    (NBBY * sizeof(xfs_inofree_t))
  37#define XFS_INODES_PER_CHUNK_LOG        (XFS_NBBYLOG + 3)
  38#define XFS_INOBT_ALL_FREE      ((xfs_inofree_t)-1)
  39
  40#define XFS_INOBT_MASKN(i,n)            xfs_inobt_maskn(i,n)
  41static inline xfs_inofree_t xfs_inobt_maskn(int i, int n)
  42{
  43        return (((n) >= XFS_INODES_PER_CHUNK ? \
  44                (xfs_inofree_t)0 : ((xfs_inofree_t)1 << (n))) - 1) << (i);
  45}
  46
  47/*
  48 * Data record structure
  49 */
  50typedef struct xfs_inobt_rec {
  51        __be32          ir_startino;    /* starting inode number */
  52        __be32          ir_freecount;   /* count of free inodes (set bits) */
  53        __be64          ir_free;        /* free inode mask */
  54} xfs_inobt_rec_t;
  55
  56typedef struct xfs_inobt_rec_incore {
  57        xfs_agino_t     ir_startino;    /* starting inode number */
  58        __int32_t       ir_freecount;   /* count of free inodes (set bits) */
  59        xfs_inofree_t   ir_free;        /* free inode mask */
  60} xfs_inobt_rec_incore_t;
  61
  62
  63/*
  64 * Key structure
  65 */
  66typedef struct xfs_inobt_key {
  67        __be32          ir_startino;    /* starting inode number */
  68} xfs_inobt_key_t;
  69
  70/* btree pointer type */
  71typedef __be32 xfs_inobt_ptr_t;
  72
  73/* btree block header type */
  74typedef struct xfs_btree_sblock xfs_inobt_block_t;
  75
  76#define XFS_BUF_TO_INOBT_BLOCK(bp)      ((xfs_inobt_block_t *)XFS_BUF_PTR(bp))
  77
  78/*
  79 * Bit manipulations for ir_free.
  80 */
  81#define XFS_INOBT_MASK(i)               ((xfs_inofree_t)1 << (i))
  82#define XFS_INOBT_IS_FREE(rp,i)         \
  83                (((rp)->ir_free & XFS_INOBT_MASK(i)) != 0)
  84#define XFS_INOBT_SET_FREE(rp,i)        ((rp)->ir_free |= XFS_INOBT_MASK(i))
  85#define XFS_INOBT_CLR_FREE(rp,i)        ((rp)->ir_free &= ~XFS_INOBT_MASK(i))
  86
  87/*
  88 * Real block structures have a size equal to the disk block size.
  89 */
  90#define XFS_INOBT_BLOCK_MAXRECS(lev,cur) ((cur)->bc_mp->m_inobt_mxr[lev != 0])
  91#define XFS_INOBT_BLOCK_MINRECS(lev,cur) ((cur)->bc_mp->m_inobt_mnr[lev != 0])
  92#define XFS_INOBT_IS_LAST_REC(cur)      \
  93        ((cur)->bc_ptrs[0] == be16_to_cpu(XFS_BUF_TO_INOBT_BLOCK((cur)->bc_bufs[0])->bb_numrecs))
  94
  95/*
  96 * Maximum number of inode btree levels.
  97 */
  98#define XFS_IN_MAXLEVELS(mp)            ((mp)->m_in_maxlevels)
  99
 100/*
 101 * block numbers in the AG.
 102 */
 103#define XFS_IBT_BLOCK(mp)               ((xfs_agblock_t)(XFS_CNT_BLOCK(mp) + 1))
 104#define XFS_PREALLOC_BLOCKS(mp)         ((xfs_agblock_t)(XFS_IBT_BLOCK(mp) + 1))
 105
 106/*
 107 * Record, key, and pointer address macros for btree blocks.
 108 */
 109#define XFS_INOBT_REC_ADDR(bb,i,cur) \
 110        (XFS_BTREE_REC_ADDR(xfs_inobt, bb, i))
 111
 112#define XFS_INOBT_KEY_ADDR(bb,i,cur) \
 113        (XFS_BTREE_KEY_ADDR(xfs_inobt, bb, i))
 114
 115#define XFS_INOBT_PTR_ADDR(bb,i,cur) \
 116        (XFS_BTREE_PTR_ADDR(xfs_inobt, bb, \
 117                                i, XFS_INOBT_BLOCK_MAXRECS(1, cur)))
 118
 119/*
 120 * Decrement cursor by one record at the level.
 121 * For nonzero levels the leaf-ward information is untouched.
 122 */
 123extern int xfs_inobt_decrement(struct xfs_btree_cur *cur, int level, int *stat);
 124
 125/*
 126 * Delete the record pointed to by cur.
 127 * The cursor refers to the place where the record was (could be inserted)
 128 * when the operation returns.
 129 */
 130extern int xfs_inobt_delete(struct xfs_btree_cur *cur, int *stat);
 131
 132/*
 133 * Get the data from the pointed-to record.
 134 */
 135extern int xfs_inobt_get_rec(struct xfs_btree_cur *cur, xfs_agino_t *ino,
 136                             __int32_t *fcnt, xfs_inofree_t *free, int *stat);
 137
 138/*
 139 * Increment cursor by one record at the level.
 140 * For nonzero levels the leaf-ward information is untouched.
 141 */
 142extern int xfs_inobt_increment(struct xfs_btree_cur *cur, int level, int *stat);
 143
 144/*
 145 * Insert the current record at the point referenced by cur.
 146 * The cursor may be inconsistent on return if splits have been done.
 147 */
 148extern int xfs_inobt_insert(struct xfs_btree_cur *cur, int *stat);
 149
 150/*
 151 * Lookup the record equal to ino in the btree given by cur.
 152 */
 153extern int xfs_inobt_lookup_eq(struct xfs_btree_cur *cur, xfs_agino_t ino,
 154                                __int32_t fcnt, xfs_inofree_t free, int *stat);
 155
 156/*
 157 * Lookup the first record greater than or equal to ino
 158 * in the btree given by cur.
 159 */
 160extern int xfs_inobt_lookup_ge(struct xfs_btree_cur *cur, xfs_agino_t ino,
 161                                __int32_t fcnt, xfs_inofree_t free, int *stat);
 162
 163/*
 164 * Lookup the first record less than or equal to ino
 165 * in the btree given by cur.
 166 */
 167extern int xfs_inobt_lookup_le(struct xfs_btree_cur *cur, xfs_agino_t ino,
 168                                __int32_t fcnt, xfs_inofree_t free, int *stat);
 169
 170/*
 171 * Update the record referred to by cur, to the value given
 172 * by [ino, fcnt, free].
 173 * This either works (return 0) or gets an EFSCORRUPTED error.
 174 */
 175extern int xfs_inobt_update(struct xfs_btree_cur *cur, xfs_agino_t ino,
 176                                __int32_t fcnt, xfs_inofree_t free);
 177
 178#endif  /* __XFS_IALLOC_BTREE_H__ */
 179