libxfs/xfs_rmap_btree.h

   1 /*
   2  * Copyright (c) 2014 Red Hat, 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_RMAP_BTREE_H__
  19 #define __XFS_RMAP_BTREE_H__
  20
  21 struct xfs_buf;
  22 struct xfs_btree_cur;
  23 struct xfs_mount;
  24
  25 /* rmaps only exist on crc enabled filesystems */
  26 #define XFS_RMAP_BLOCK_LEN      XFS_BTREE_SBLOCK_CRC_LEN
  27
  28 /*
  29  * Record, key, and pointer address macros for btree blocks.
  30  *
  31  * (note that some of these may appear unused, but they are used in userspace)
  32  */
  33 #define XFS_RMAP_REC_ADDR(block, index) \
  34         ((struct xfs_rmap_rec *) \
  35                 ((char *)(block) + XFS_RMAP_BLOCK_LEN + \
  36                  (((index) - 1) * sizeof(struct xfs_rmap_rec))))
  37
  38 #define XFS_RMAP_KEY_ADDR(block, index) \
  39         ((struct xfs_rmap_key *) \
  40                 ((char *)(block) + XFS_RMAP_BLOCK_LEN + \
  41                  ((index) - 1) * 2 * sizeof(struct xfs_rmap_key)))
  42
  43 #define XFS_RMAP_HIGH_KEY_ADDR(block, index) \
  44         ((struct xfs_rmap_key *) \
  45                 ((char *)(block) + XFS_RMAP_BLOCK_LEN + \
  46                  sizeof(struct xfs_rmap_key) + \
  47                  ((index) - 1) * 2 * sizeof(struct xfs_rmap_key)))
  48
  49 #define XFS_RMAP_PTR_ADDR(block, index, maxrecs) \
  50         ((xfs_rmap_ptr_t *) \
  51                 ((char *)(block) + XFS_RMAP_BLOCK_LEN + \
  52                  (maxrecs) * 2 * sizeof(struct xfs_rmap_key) + \
  53                  ((index) - 1) * sizeof(xfs_rmap_ptr_t)))
  54
  55 struct xfs_btree_cur *xfs_rmapbt_init_cursor(struct xfs_mount *mp,
  56                                 struct xfs_trans *tp, struct xfs_buf *bp,
  57                                 xfs_agnumber_t agno);
  58 int xfs_rmapbt_maxrecs(struct xfs_mount *mp, int blocklen, int leaf);
  59 extern void xfs_rmapbt_compute_maxlevels(struct xfs_mount *mp);
  60
  61 extern xfs_extlen_t xfs_rmapbt_calc_size(struct xfs_mount *mp,
  62                 unsigned long long len);
  63 extern xfs_extlen_t xfs_rmapbt_max_size(struct xfs_mount *mp,
  64                 xfs_agblock_t agblocks);
  65
  66 extern int xfs_rmapbt_calc_reserves(struct xfs_mount *mp,
  67                 xfs_agnumber_t agno, xfs_extlen_t *ask, xfs_extlen_t *used);
  68
  69 #endif /* __XFS_RMAP_BTREE_H__ */