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/*
* 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_btree_sblock;
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;
/* btree block header type */
typedef struct xfs_btree_sblock xfs_alloc_block_t;
#define XFS_BUF_TO_ALLOC_BLOCK(bp) ((xfs_alloc_block_t *)XFS_BUF_PTR(bp))
/*
* Real block structures have a size equal to the disk block size.
*/
#define XFS_ALLOC_BLOCK_SIZE(lev,cur) (1 << (cur)->bc_blocklog)
#define XFS_ALLOC_BLOCK_MAXRECS(lev,cur) ((cur)->bc_mp->m_alloc_mxr[lev != 0])
#define XFS_ALLOC_BLOCK_MINRECS(lev,cur) ((cur)->bc_mp->m_alloc_mnr[lev != 0])
/*
* Minimum and maximum blocksize and sectorsize.
* The blocksize upper limit is pretty much arbitrary.
* The sectorsize upper limit is due to sizeof(sb_sectsize).
*/
#define XFS_MIN_BLOCKSIZE_LOG 9 /* i.e. 512 bytes */
#define XFS_MAX_BLOCKSIZE_LOG 16 /* i.e. 65536 bytes */
#define XFS_MIN_BLOCKSIZE (1 << XFS_MIN_BLOCKSIZE_LOG)
#define XFS_MAX_BLOCKSIZE (1 << XFS_MAX_BLOCKSIZE_LOG)
#define XFS_MIN_SECTORSIZE_LOG 9 /* i.e. 512 bytes */
#define XFS_MAX_SECTORSIZE_LOG 15 /* i.e. 32768 bytes */
#define XFS_MIN_SECTORSIZE (1 << XFS_MIN_SECTORSIZE_LOG)
#define XFS_MAX_SECTORSIZE (1 << XFS_MAX_SECTORSIZE_LOG)
/*
* 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))
/*
* Record, key, and pointer address macros for btree blocks.
*/
#define XFS_ALLOC_REC_ADDR(bb,i,cur) \
XFS_BTREE_REC_ADDR(XFS_ALLOC_BLOCK_SIZE(0,cur), xfs_alloc, \
bb, i, XFS_ALLOC_BLOCK_MAXRECS(0, cur))
#define XFS_ALLOC_KEY_ADDR(bb,i,cur) \
XFS_BTREE_KEY_ADDR(XFS_ALLOC_BLOCK_SIZE(1,cur), xfs_alloc, \
bb, i, XFS_ALLOC_BLOCK_MAXRECS(1, cur))
#define XFS_ALLOC_PTR_ADDR(bb,i,cur) \
XFS_BTREE_PTR_ADDR(XFS_ALLOC_BLOCK_SIZE(1,cur), xfs_alloc, \
bb, i, XFS_ALLOC_BLOCK_MAXRECS(1, cur))
/*
* Decrement cursor by one record at the level.
* For nonzero levels the leaf-ward information is untouched.
*/
extern int xfs_alloc_decrement(struct xfs_btree_cur *cur, int level, int *stat);
/*
* Delete the record pointed to by cur.
* The cursor refers to the place where the record was (could be inserted)
* when the operation returns.
*/
extern int xfs_alloc_delete(struct xfs_btree_cur *cur, int *stat);
/*
* Get the data from the pointed-to record.
*/
extern int xfs_alloc_get_rec(struct xfs_btree_cur *cur, xfs_agblock_t *bno,
xfs_extlen_t *len, int *stat);
/*
* Increment cursor by one record at the level.
* For nonzero levels the leaf-ward information is untouched.
*/
extern int xfs_alloc_increment(struct xfs_btree_cur *cur, int level, int *stat);
/*
* Insert the current record at the point referenced by cur.
* The cursor may be inconsistent on return if splits have been done.
*/
extern int xfs_alloc_insert(struct xfs_btree_cur *cur, int *stat);
/*
* Lookup the record equal to [bno, len] in the btree given by cur.
*/
extern int xfs_alloc_lookup_eq(struct xfs_btree_cur *cur, xfs_agblock_t bno,
xfs_extlen_t len, int *stat);
/*
* Lookup the first record greater than or equal to [bno, len]
* in the btree given by cur.
*/
extern int xfs_alloc_lookup_ge(struct xfs_btree_cur *cur, xfs_agblock_t bno,
xfs_extlen_t len, int *stat);
/*
* Lookup the first record less than or equal to [bno, len]
* in the btree given by cur.
*/
extern int xfs_alloc_lookup_le(struct xfs_btree_cur *cur, xfs_agblock_t bno,
xfs_extlen_t len, int *stat);
/*
* Update the record referred to by cur, to the value given by [bno, len].
* This either works (return 0) or gets an EFSCORRUPTED error.
*/
extern int xfs_alloc_update(struct xfs_btree_cur *cur, xfs_agblock_t bno,
xfs_extlen_t len);
#endif /* __XFS_ALLOC_BTREE_H__ */
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