fs/xfs/xfs_ialloc_btree.h

   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
  25 struct xfs_buf;
  26 struct xfs_btree_cur;
  27 struct xfs_mount;
  28
  29 /*
  30  * There is a btree for the inode map per allocation group.
  31  */
  32 #define XFS_IBT_MAGIC   0x49414254      /* 'IABT' */
  33
  34 typedef __uint64_t      xfs_inofree_t;
  35 #define XFS_INODES_PER_CHUNK    (NBBY * sizeof(xfs_inofree_t))
  36 #define XFS_INODES_PER_CHUNK_LOG        (XFS_NBBYLOG + 3)
  37 #define XFS_INOBT_ALL_FREE      ((xfs_inofree_t)-1)
  38
  39 static inline xfs_inofree_t xfs_inobt_maskn(int i, int n)
  40 {
  41         return (((n) >= XFS_INODES_PER_CHUNK ? \
  42                 (xfs_inofree_t)0 : ((xfs_inofree_t)1 << (n))) - 1) << (i);
  43 }
  44
  45 /*
  46  * Data record structure
  47  */
  48 typedef struct xfs_inobt_rec {
  49         __be32          ir_startino;    /* starting inode number */
  50         __be32          ir_freecount;   /* count of free inodes (set bits) */
  51         __be64          ir_free;        /* free inode mask */
  52 } xfs_inobt_rec_t;
  53
  54 typedef struct xfs_inobt_rec_incore {
  55         xfs_agino_t     ir_startino;    /* starting inode number */
  56         __int32_t       ir_freecount;   /* count of free inodes (set bits) */
  57         xfs_inofree_t   ir_free;        /* free inode mask */
  58 } xfs_inobt_rec_incore_t;
  59
  60
  61 /*
  62  * Key structure
  63  */
  64 typedef struct xfs_inobt_key {
  65         __be32          ir_startino;    /* starting inode number */
  66 } xfs_inobt_key_t;
  67
  68 /* btree pointer type */
  69 typedef __be32 xfs_inobt_ptr_t;
  70
  71 /*
  72  * Bit manipulations for ir_free.
  73  */
  74 #define XFS_INOBT_MASK(i)               ((xfs_inofree_t)1 << (i))
  75 #define XFS_INOBT_IS_FREE(rp,i)         \
  76                 (((rp)->ir_free & XFS_INOBT_MASK(i)) != 0)
  77 #define XFS_INOBT_SET_FREE(rp,i)        ((rp)->ir_free |= XFS_INOBT_MASK(i))
  78 #define XFS_INOBT_CLR_FREE(rp,i)        ((rp)->ir_free &= ~XFS_INOBT_MASK(i))
  79
  80 /*
  81  * Maximum number of inode btree levels.
  82  */
  83 #define XFS_IN_MAXLEVELS(mp)            ((mp)->m_in_maxlevels)
  84
  85 /*
  86  * block numbers in the AG.
  87  */
  88 #define XFS_IBT_BLOCK(mp)               ((xfs_agblock_t)(XFS_CNT_BLOCK(mp) + 1))
  89 #define XFS_PREALLOC_BLOCKS(mp)         ((xfs_agblock_t)(XFS_IBT_BLOCK(mp) + 1))
  90
  91 /*
  92  * Btree block header size depends on a superblock flag.
  93  *
  94  * (not quite yet, but soon)
  95  */
  96 #define XFS_INOBT_BLOCK_LEN(mp) XFS_BTREE_SBLOCK_LEN
  97
  98 /*
  99  * Record, key, and pointer address macros for btree blocks.
 100  *
 101  * (note that some of these may appear unused, but they are used in userspace)
 102  */
 103 #define XFS_INOBT_REC_ADDR(mp, block, index) \
 104         ((xfs_inobt_rec_t *) \
 105                 ((char *)(block) + \
 106                  XFS_INOBT_BLOCK_LEN(mp) + \
 107                  (((index) - 1) * sizeof(xfs_inobt_rec_t))))
 108
 109 #define XFS_INOBT_KEY_ADDR(mp, block, index) \
 110         ((xfs_inobt_key_t *) \
 111                 ((char *)(block) + \
 112                  XFS_INOBT_BLOCK_LEN(mp) + \
 113                  ((index) - 1) * sizeof(xfs_inobt_key_t)))
 114
 115 #define XFS_INOBT_PTR_ADDR(mp, block, index, maxrecs) \
 116         ((xfs_inobt_ptr_t *) \
 117                 ((char *)(block) + \
 118                  XFS_INOBT_BLOCK_LEN(mp) + \
 119                  (maxrecs) * sizeof(xfs_inobt_key_t) + \
 120                  ((index) - 1) * sizeof(xfs_inobt_ptr_t)))
 121
 122 extern struct xfs_btree_cur *xfs_inobt_init_cursor(struct xfs_mount *,
 123                 struct xfs_trans *, struct xfs_buf *, xfs_agnumber_t);
 124 extern int xfs_inobt_maxrecs(struct xfs_mount *, int, int);
 125
 126 #endif  /* __XFS_IALLOC_BTREE_H__ */