/*
* Copyright (c) 2000,2005 Silicon Graphics, Inc.
* All Rights Reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it would be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef __XFS_ALLOC_BTREE_H__
#define __XFS_ALLOC_BTREE_H__
/*
* Freespace on-disk structures
*/
struct xfs_buf;
struct xfs_btree_cur;
struct xfs_mount;
/*
* There are two on-disk btrees, one sorted by blockno and one sorted
* by blockcount and blockno. All blocks look the same to make the code
* simpler; if we have time later, we'll make the optimizations.
*/
#define XFS_ABTB_MAGIC 0x41425442 /* 'ABTB' for bno tree */
#define XFS_ABTC_MAGIC 0x41425443 /* 'ABTC' for cnt tree */
/*
* Data record/key structure
*/
typedef struct xfs_alloc_rec {
__be32 ar_startblock; /* starting block number */
__be32 ar_blockcount; /* count of free blocks */
} xfs_alloc_rec_t, xfs_alloc_key_t;
typedef struct xfs_alloc_rec_incore {
xfs_agblock_t ar_startblock; /* starting block number */
xfs_extlen_t ar_blockcount; /* count of free blocks */
} xfs_alloc_rec_incore_t;
/* btree pointer type */
typedef __be32 xfs_alloc_ptr_t;
/*
* Block numbers in the AG:
* SB is sector 0, AGF is sector 1, AGI is sector 2, AGFL is sector 3.
*/
#define XFS_BNO_BLOCK(mp) ((xfs_agblock_t)(XFS_AGFL_BLOCK(mp) + 1))
#define XFS_CNT_BLOCK(mp) ((xfs_agblock_t)(XFS_BNO_BLOCK(mp) + 1))
/*
* Btree block header size depends on a superblock flag.
*
* (not quite yet, but soon)
*/
#define XFS_ALLOC_BLOCK_LEN(mp) XFS_BTREE_SBLOCK_LEN
/*
* Record, key, and pointer address macros for btree blocks.
*
* (note that some of these may appear unused, but they are used in userspace)
*/
#define XFS_ALLOC_REC_ADDR(mp, block, index) \
((xfs_alloc_rec_t *) \
((char *)(block) + \
XFS_ALLOC_BLOCK_LEN(mp) + \
(((index) - 1) * sizeof(xfs_alloc_rec_t))))
#define XFS_ALLOC_KEY_ADDR(mp, block, index) \
((xfs_alloc_key_t *) \
((char *)(block) + \
XFS_ALLOC_BLOCK_LEN(mp) + \
((index) - 1) * sizeof(xfs_alloc_key_t)))
#define XFS_ALLOC_PTR_ADDR(mp, block, index, maxrecs) \
((xfs_alloc_ptr_t *) \
((char *)(block) + \
XFS_ALLOC_BLOCK_LEN(mp) + \
(maxrecs) * sizeof(xfs_alloc_key_t) + \
((index) - 1) * sizeof(xfs_alloc_ptr_t)))
extern struct xfs_btree_cur *xfs_allocbt_init_cursor(struct xfs_mount *,
struct xfs_trans *, struct xfs_buf *,
xfs_agnumber_t, xfs_btnum_t);
extern int xfs_allocbt_maxrecs(struct xfs_mount *, int, int);
extern const struct xfs_buf_ops xfs_allocbt_buf_ops;
#endif /* __XFS_ALLOC_BTREE_H__ */
