[linux-block.git] / fs / xfs / xfs_alloc_btree.h

/*
 * 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_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, bb, i)

#define	XFS_ALLOC_KEY_ADDR(bb,i,cur)	\
	XFS_BTREE_KEY_ADDR(xfs_alloc, bb, i)

#define	XFS_ALLOC_PTR_ADDR(bb,i,cur)	\
	XFS_BTREE_PTR_ADDR(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__ */
Commit	Line	Data
1da177e4	1	/*
7b718769 NS	2	* Copyright (c) 2000,2005 Silicon Graphics, Inc.
7b718769 NS	3	* All Rights Reserved.
1da177e4	4	*
7b718769 NS	5	* This program is free software; you can redistribute it and/or
7b718769 NS	6	* modify it under the terms of the GNU General Public License as
1da177e4 LT	7	* published by the Free Software Foundation.
1da177e4 LT	8	*
7b718769 NS	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.
1da177e4	13	*
7b718769 NS	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
1da177e4 LT	17	*/
	18	#ifndef __XFS_ALLOC_BTREE_H__
	19	#define __XFS_ALLOC_BTREE_H__
	20
	21	/*
	22	* Freespace on-disk structures
	23	*/
	24
	25	struct xfs_buf;
	26	struct xfs_btree_cur;
	27	struct xfs_btree_sblock;
	28	struct xfs_mount;
	29
	30	/*
	31	* There are two on-disk btrees, one sorted by blockno and one sorted
	32	* by blockcount and blockno. All blocks look the same to make the code
	33	* simpler; if we have time later, we'll make the optimizations.
	34	*/
	35	#define XFS_ABTB_MAGIC 0x41425442 /* 'ABTB' for bno tree */
	36	#define XFS_ABTC_MAGIC 0x41425443 /* 'ABTC' for cnt tree */
	37
	38	/*
	39	* Data record/key structure
	40	*/
16259e7d CH	41	typedef struct xfs_alloc_rec {
	42	__be32 ar_startblock; /* starting block number */
	43	__be32 ar_blockcount; /* count of free blocks */
	44	} xfs_alloc_rec_t, xfs_alloc_key_t;
	45
	46	typedef struct xfs_alloc_rec_incore {
1da177e4 LT	47	xfs_agblock_t ar_startblock; /* starting block number */
1da177e4 LT	48	xfs_extlen_t ar_blockcount; /* count of free blocks */
16259e7d	49	} xfs_alloc_rec_incore_t;
1da177e4	50
16259e7d CH	51	/* btree pointer type */
	52	typedef __be32 xfs_alloc_ptr_t;
	53	/* btree block header type */
1da177e4 LT	54	typedef struct xfs_btree_sblock xfs_alloc_block_t;
1da177e4 LT	55
a844f451	56	#define XFS_BUF_TO_ALLOC_BLOCK(bp) ((xfs_alloc_block_t *)XFS_BUF_PTR(bp))
1da177e4 LT	57
	58	/*
	59	* Real block structures have a size equal to the disk block size.
	60	*/
a844f451 NS	61	#define XFS_ALLOC_BLOCK_MAXRECS(lev,cur) ((cur)->bc_mp->m_alloc_mxr[lev != 0])
a844f451 NS	62	#define XFS_ALLOC_BLOCK_MINRECS(lev,cur) ((cur)->bc_mp->m_alloc_mnr[lev != 0])
1da177e4 LT	63
	64	/*
	65	* Minimum and maximum blocksize and sectorsize.
	66	* The blocksize upper limit is pretty much arbitrary.
	67	* The sectorsize upper limit is due to sizeof(sb_sectsize).
	68	*/
	69	#define XFS_MIN_BLOCKSIZE_LOG 9 /* i.e. 512 bytes */
	70	#define XFS_MAX_BLOCKSIZE_LOG 16 /* i.e. 65536 bytes */
	71	#define XFS_MIN_BLOCKSIZE (1 << XFS_MIN_BLOCKSIZE_LOG)
	72	#define XFS_MAX_BLOCKSIZE (1 << XFS_MAX_BLOCKSIZE_LOG)
	73	#define XFS_MIN_SECTORSIZE_LOG 9 /* i.e. 512 bytes */
	74	#define XFS_MAX_SECTORSIZE_LOG 15 /* i.e. 32768 bytes */
	75	#define XFS_MIN_SECTORSIZE (1 << XFS_MIN_SECTORSIZE_LOG)
	76	#define XFS_MAX_SECTORSIZE (1 << XFS_MAX_SECTORSIZE_LOG)
	77
	78	/*
	79	* Block numbers in the AG:
	80	* SB is sector 0, AGF is sector 1, AGI is sector 2, AGFL is sector 3.
	81	*/
1da177e4	82	#define XFS_BNO_BLOCK(mp) ((xfs_agblock_t)(XFS_AGFL_BLOCK(mp) + 1))
1da177e4	83	#define XFS_CNT_BLOCK(mp) ((xfs_agblock_t)(XFS_BNO_BLOCK(mp) + 1))
1da177e4 LT	84
	85	/*
	86	* Record, key, and pointer address macros for btree blocks.
	87	*/
1da177e4	88	#define XFS_ALLOC_REC_ADDR(bb,i,cur) \
2c36dded	89	XFS_BTREE_REC_ADDR(xfs_alloc, bb, i)
1da177e4	90
1da177e4	91	#define XFS_ALLOC_KEY_ADDR(bb,i,cur) \
2c36dded	92	XFS_BTREE_KEY_ADDR(xfs_alloc, bb, i)
1da177e4	93
1da177e4	94	#define XFS_ALLOC_PTR_ADDR(bb,i,cur) \
2c36dded	95	XFS_BTREE_PTR_ADDR(xfs_alloc, bb, i, XFS_ALLOC_BLOCK_MAXRECS(1, cur))
1da177e4 LT	96
	97	/*
	98	* Decrement cursor by one record at the level.
	99	* For nonzero levels the leaf-ward information is untouched.
	100	*/
a844f451	101	extern int xfs_alloc_decrement(struct xfs_btree_cur cur, int level, int stat);
1da177e4 LT	102
	103	/*
	104	* Delete the record pointed to by cur.
	105	* The cursor refers to the place where the record was (could be inserted)
	106	* when the operation returns.
	107	*/
a844f451	108	extern int xfs_alloc_delete(struct xfs_btree_cur cur, int stat);
1da177e4 LT	109
	110	/*
	111	* Get the data from the pointed-to record.
	112	*/
a844f451 NS	113	extern int xfs_alloc_get_rec(struct xfs_btree_cur cur, xfs_agblock_t bno,
a844f451 NS	114	xfs_extlen_t len, int stat);
1da177e4 LT	115
	116	/*
	117	* Increment cursor by one record at the level.
	118	* For nonzero levels the leaf-ward information is untouched.
	119	*/
a844f451	120	extern int xfs_alloc_increment(struct xfs_btree_cur cur, int level, int stat);
1da177e4 LT	121
	122	/*
	123	* Insert the current record at the point referenced by cur.
	124	* The cursor may be inconsistent on return if splits have been done.
	125	*/
a844f451	126	extern int xfs_alloc_insert(struct xfs_btree_cur cur, int stat);
1da177e4 LT	127
	128	/*
	129	* Lookup the record equal to [bno, len] in the btree given by cur.
	130	*/
a844f451 NS	131	extern int xfs_alloc_lookup_eq(struct xfs_btree_cur *cur, xfs_agblock_t bno,
a844f451 NS	132	xfs_extlen_t len, int *stat);
1da177e4 LT	133
	134	/*
	135	* Lookup the first record greater than or equal to [bno, len]
	136	* in the btree given by cur.
	137	*/
a844f451 NS	138	extern int xfs_alloc_lookup_ge(struct xfs_btree_cur *cur, xfs_agblock_t bno,
a844f451 NS	139	xfs_extlen_t len, int *stat);
1da177e4 LT	140
	141	/*
	142	* Lookup the first record less than or equal to [bno, len]
	143	* in the btree given by cur.
	144	*/
a844f451 NS	145	extern int xfs_alloc_lookup_le(struct xfs_btree_cur *cur, xfs_agblock_t bno,
a844f451 NS	146	xfs_extlen_t len, int *stat);
1da177e4 LT	147
	148	/*
	149	* Update the record referred to by cur, to the value given by [bno, len].
	150	* This either works (return 0) or gets an EFSCORRUPTED error.
	151	*/
a844f451 NS	152	extern int xfs_alloc_update(struct xfs_btree_cur *cur, xfs_agblock_t bno,
a844f451 NS	153	xfs_extlen_t len);
1da177e4 LT	154
1da177e4 LT	155	#endif /* __XFS_ALLOC_BTREE_H__ */