LXR linux/fs/xfs/xfs_alloc

   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_ALLOC_BTREE_H__
  19#define __XFS_ALLOC_BTREE_H__
  20
  21/*
  22 * Freespace on-disk structures
  23 */
  24
  25struct xfs_buf;
  26struct xfs_btree_cur;
  27struct xfs_mount;
  28
  29/*
  30 * Btree block header size depends on a superblock flag.
  31 */
  32#define XFS_ALLOC_BLOCK_LEN(mp) \
  33        (xfs_sb_version_hascrc(&((mp)->m_sb)) ? \
  34                XFS_BTREE_SBLOCK_CRC_LEN : XFS_BTREE_SBLOCK_LEN)
  35
  36/*
  37 * Record, key, and pointer address macros for btree blocks.
  38 *
  39 * (note that some of these may appear unused, but they are used in userspace)
  40 */
  41#define XFS_ALLOC_REC_ADDR(mp, block, index) \
  42        ((xfs_alloc_rec_t *) \
  43                ((char *)(block) + \
  44                 XFS_ALLOC_BLOCK_LEN(mp) + \
  45                 (((index) - 1) * sizeof(xfs_alloc_rec_t))))
  46
  47#define XFS_ALLOC_KEY_ADDR(mp, block, index) \
  48        ((xfs_alloc_key_t *) \
  49                ((char *)(block) + \
  50                 XFS_ALLOC_BLOCK_LEN(mp) + \
  51                 ((index) - 1) * sizeof(xfs_alloc_key_t)))
  52
  53#define XFS_ALLOC_PTR_ADDR(mp, block, index, maxrecs) \
  54        ((xfs_alloc_ptr_t *) \
  55                ((char *)(block) + \
  56                 XFS_ALLOC_BLOCK_LEN(mp) + \
  57                 (maxrecs) * sizeof(xfs_alloc_key_t) + \
  58                 ((index) - 1) * sizeof(xfs_alloc_ptr_t)))
  59
  60extern struct xfs_btree_cur *xfs_allocbt_init_cursor(struct xfs_mount *,
  61                struct xfs_trans *, struct xfs_buf *,
  62                xfs_agnumber_t, xfs_btnum_t);
  63extern int xfs_allocbt_maxrecs(struct xfs_mount *, int, int);
  64
  65#endif  /* __XFS_ALLOC_BTREE_H__ */
  66