[deliverable/linux.git] / fs / xfs / xfs_alloc_btree.h

/*
 * Copyright (c) 2000 Silicon Graphics, Inc.  All Rights Reserved.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of version 2 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.
 *
 * Further, this software is distributed without any warranty that it is
 * free of the rightful claim of any third person regarding infringement
 * or the like.  Any license provided herein, whether implied or
 * otherwise, applies only to this software file.  Patent licenses, if
 * any, provided herein do not apply to combinations of this program with
 * other software, or any other product whatsoever.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write the Free Software Foundation, Inc., 59
 * Temple Place - Suite 330, Boston MA 02111-1307, USA.
 *
 * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
 * Mountain View, CA  94043, or:
 *
 * http://www.sgi.com
 *
 * For further information regarding this notice, see:
 *
 * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
 */
#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
{
	xfs_agblock_t	ar_startblock;	/* starting block number */
	xfs_extlen_t	ar_blockcount;	/* count of free blocks */
} xfs_alloc_rec_t, xfs_alloc_key_t;

typedef xfs_agblock_t xfs_alloc_ptr_t;	/* btree pointer type */
					/* 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__ */
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Copyright (c) 2000 Silicon Graphics, Inc. All Rights Reserved.
	3	*
	4	* This program is free software; you can redistribute it and/or modify it
	5	* under the terms of version 2 of the GNU General Public License as
	6	* published by the Free Software Foundation.
	7	*
	8	* This program is distributed in the hope that it would be useful, but
	9	* WITHOUT ANY WARRANTY; without even the implied warranty of
	10	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
	11	*
	12	* Further, this software is distributed without any warranty that it is
	13	* free of the rightful claim of any third person regarding infringement
	14	* or the like. Any license provided herein, whether implied or
	15	* otherwise, applies only to this software file. Patent licenses, if
	16	* any, provided herein do not apply to combinations of this program with
	17	* other software, or any other product whatsoever.
	18	*
	19	* You should have received a copy of the GNU General Public License along
	20	* with this program; if not, write the Free Software Foundation, Inc., 59
	21	* Temple Place - Suite 330, Boston MA 02111-1307, USA.
	22	*
	23	* Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
	24	* Mountain View, CA 94043, or:
	25	*
	26	* http://www.sgi.com
	27	*
	28	* For further information regarding this notice, see:
	29	*
	30	* http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
	31	*/
	32	#ifndef __XFS_ALLOC_BTREE_H__
	33	#define __XFS_ALLOC_BTREE_H__
	34
	35	/*
	36	* Freespace on-disk structures
	37	*/
	38
	39	struct xfs_buf;
	40	struct xfs_btree_cur;
	41	struct xfs_btree_sblock;
	42	struct xfs_mount;
	43
	44	/*
	45	* There are two on-disk btrees, one sorted by blockno and one sorted
	46	* by blockcount and blockno. All blocks look the same to make the code
	47	* simpler; if we have time later, we'll make the optimizations.
	48	*/
	49	#define XFS_ABTB_MAGIC 0x41425442 /* 'ABTB' for bno tree */
	50	#define XFS_ABTC_MAGIC 0x41425443 /* 'ABTC' for cnt tree */
	51
	52	/*
	53	* Data record/key structure
	54	*/
	55	typedef struct xfs_alloc_rec
	56	{
	57	xfs_agblock_t ar_startblock; /* starting block number */
	58	xfs_extlen_t ar_blockcount; /* count of free blocks */
	59	} xfs_alloc_rec_t, xfs_alloc_key_t;
	60
	61	typedef xfs_agblock_t xfs_alloc_ptr_t; /* btree pointer type */
	62	/* btree block header type */
	63	typedef struct xfs_btree_sblock xfs_alloc_block_t;
	64
a844f451	65	#define XFS_BUF_TO_ALLOC_BLOCK(bp) ((xfs_alloc_block_t *)XFS_BUF_PTR(bp))
1da177e4 LT	66
	67	/*
	68	* Real block structures have a size equal to the disk block size.
	69	*/
1da177e4	70	#define XFS_ALLOC_BLOCK_SIZE(lev,cur) (1 << (cur)->bc_blocklog)
a844f451 NS	71	#define XFS_ALLOC_BLOCK_MAXRECS(lev,cur) ((cur)->bc_mp->m_alloc_mxr[lev != 0])
a844f451 NS	72	#define XFS_ALLOC_BLOCK_MINRECS(lev,cur) ((cur)->bc_mp->m_alloc_mnr[lev != 0])
1da177e4 LT	73
	74	/*
	75	* Minimum and maximum blocksize and sectorsize.
	76	* The blocksize upper limit is pretty much arbitrary.
	77	* The sectorsize upper limit is due to sizeof(sb_sectsize).
	78	*/
	79	#define XFS_MIN_BLOCKSIZE_LOG 9 /* i.e. 512 bytes */
	80	#define XFS_MAX_BLOCKSIZE_LOG 16 /* i.e. 65536 bytes */
	81	#define XFS_MIN_BLOCKSIZE (1 << XFS_MIN_BLOCKSIZE_LOG)
	82	#define XFS_MAX_BLOCKSIZE (1 << XFS_MAX_BLOCKSIZE_LOG)
	83	#define XFS_MIN_SECTORSIZE_LOG 9 /* i.e. 512 bytes */
	84	#define XFS_MAX_SECTORSIZE_LOG 15 /* i.e. 32768 bytes */
	85	#define XFS_MIN_SECTORSIZE (1 << XFS_MIN_SECTORSIZE_LOG)
	86	#define XFS_MAX_SECTORSIZE (1 << XFS_MAX_SECTORSIZE_LOG)
	87
	88	/*
	89	* Block numbers in the AG:
	90	* SB is sector 0, AGF is sector 1, AGI is sector 2, AGFL is sector 3.
	91	*/
1da177e4	92	#define XFS_BNO_BLOCK(mp) ((xfs_agblock_t)(XFS_AGFL_BLOCK(mp) + 1))
1da177e4	93	#define XFS_CNT_BLOCK(mp) ((xfs_agblock_t)(XFS_BNO_BLOCK(mp) + 1))
1da177e4 LT	94
	95	/*
	96	* Record, key, and pointer address macros for btree blocks.
	97	*/
1da177e4	98	#define XFS_ALLOC_REC_ADDR(bb,i,cur) \
a844f451 NS	99	XFS_BTREE_REC_ADDR(XFS_ALLOC_BLOCK_SIZE(0,cur), xfs_alloc, \
a844f451 NS	100	bb, i, XFS_ALLOC_BLOCK_MAXRECS(0, cur))
1da177e4	101
1da177e4	102	#define XFS_ALLOC_KEY_ADDR(bb,i,cur) \
a844f451 NS	103	XFS_BTREE_KEY_ADDR(XFS_ALLOC_BLOCK_SIZE(1,cur), xfs_alloc, \
a844f451 NS	104	bb, i, XFS_ALLOC_BLOCK_MAXRECS(1, cur))
1da177e4	105
1da177e4	106	#define XFS_ALLOC_PTR_ADDR(bb,i,cur) \
a844f451 NS	107	XFS_BTREE_PTR_ADDR(XFS_ALLOC_BLOCK_SIZE(1,cur), xfs_alloc, \
a844f451 NS	108	bb, i, XFS_ALLOC_BLOCK_MAXRECS(1, cur))
1da177e4 LT	109
	110	/*
	111	* Decrement cursor by one record at the level.
	112	* For nonzero levels the leaf-ward information is untouched.
	113	*/
a844f451	114	extern int xfs_alloc_decrement(struct xfs_btree_cur cur, int level, int stat);
1da177e4 LT	115
	116	/*
	117	* Delete the record pointed to by cur.
	118	* The cursor refers to the place where the record was (could be inserted)
	119	* when the operation returns.
	120	*/
a844f451	121	extern int xfs_alloc_delete(struct xfs_btree_cur cur, int stat);
1da177e4 LT	122
	123	/*
	124	* Get the data from the pointed-to record.
	125	*/
a844f451 NS	126	extern int xfs_alloc_get_rec(struct xfs_btree_cur cur, xfs_agblock_t bno,
a844f451 NS	127	xfs_extlen_t len, int stat);
1da177e4 LT	128
	129	/*
	130	* Increment cursor by one record at the level.
	131	* For nonzero levels the leaf-ward information is untouched.
	132	*/
a844f451	133	extern int xfs_alloc_increment(struct xfs_btree_cur cur, int level, int stat);
1da177e4 LT	134
	135	/*
	136	* Insert the current record at the point referenced by cur.
	137	* The cursor may be inconsistent on return if splits have been done.
	138	*/
a844f451	139	extern int xfs_alloc_insert(struct xfs_btree_cur cur, int stat);
1da177e4 LT	140
	141	/*
	142	* Lookup the record equal to [bno, len] in the btree given by cur.
	143	*/
a844f451 NS	144	extern int xfs_alloc_lookup_eq(struct xfs_btree_cur *cur, xfs_agblock_t bno,
a844f451 NS	145	xfs_extlen_t len, int *stat);
1da177e4 LT	146
	147	/*
	148	* Lookup the first record greater than or equal to [bno, len]
	149	* in the btree given by cur.
	150	*/
a844f451 NS	151	extern int xfs_alloc_lookup_ge(struct xfs_btree_cur *cur, xfs_agblock_t bno,
a844f451 NS	152	xfs_extlen_t len, int *stat);
1da177e4 LT	153
	154	/*
	155	* Lookup the first record less than or equal to [bno, len]
	156	* in the btree given by cur.
	157	*/
a844f451 NS	158	extern int xfs_alloc_lookup_le(struct xfs_btree_cur *cur, xfs_agblock_t bno,
a844f451 NS	159	xfs_extlen_t len, int *stat);
1da177e4 LT	160
	161	/*
	162	* Update the record referred to by cur, to the value given by [bno, len].
	163	* This either works (return 0) or gets an EFSCORRUPTED error.
	164	*/
a844f451 NS	165	extern int xfs_alloc_update(struct xfs_btree_cur *cur, xfs_agblock_t bno,
a844f451 NS	166	xfs_extlen_t len);
1da177e4 LT	167
1da177e4 LT	168	#endif /* __XFS_ALLOC_BTREE_H__ */