[net-next-2.6.git] / fs / xfs / xfs_btree.h

/*
 * Copyright (c) 2000-2001,2005 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_BTREE_H__
#define	__XFS_BTREE_H__

struct xfs_buf;
struct xfs_bmap_free;
struct xfs_inode;
struct xfs_mount;
struct xfs_trans;

extern kmem_zone_t	*xfs_btree_cur_zone;

/*
 * This nonsense is to make -wlint happy.
 */
#define	XFS_LOOKUP_EQ	((xfs_lookup_t)XFS_LOOKUP_EQi)
#define	XFS_LOOKUP_LE	((xfs_lookup_t)XFS_LOOKUP_LEi)
#define	XFS_LOOKUP_GE	((xfs_lookup_t)XFS_LOOKUP_GEi)

#define	XFS_BTNUM_BNO	((xfs_btnum_t)XFS_BTNUM_BNOi)
#define	XFS_BTNUM_CNT	((xfs_btnum_t)XFS_BTNUM_CNTi)
#define	XFS_BTNUM_BMAP	((xfs_btnum_t)XFS_BTNUM_BMAPi)
#define	XFS_BTNUM_INO	((xfs_btnum_t)XFS_BTNUM_INOi)

/*
 * Short form header: space allocation btrees.
 */
typedef struct xfs_btree_sblock {
	__be32		bb_magic;	/* magic number for block type */
	__be16		bb_level;	/* 0 is a leaf */
	__be16		bb_numrecs;	/* current # of data records */
	__be32		bb_leftsib;	/* left sibling block or NULLAGBLOCK */
	__be32		bb_rightsib;	/* right sibling block or NULLAGBLOCK */
} xfs_btree_sblock_t;

/*
 * Long form header: bmap btrees.
 */
typedef struct xfs_btree_lblock {
	__be32		bb_magic;	/* magic number for block type */
	__be16		bb_level;	/* 0 is a leaf */
	__be16		bb_numrecs;	/* current # of data records */
	__be64		bb_leftsib;	/* left sibling block or NULLDFSBNO */
	__be64		bb_rightsib;	/* right sibling block or NULLDFSBNO */
} xfs_btree_lblock_t;

/*
 * Combined header and structure, used by common code.
 */
typedef struct xfs_btree_block {
	__be32		bb_magic;	/* magic number for block type */
	__be16		bb_level;	/* 0 is a leaf */
	__be16		bb_numrecs;	/* current # of data records */
	union {
		struct {
			__be32		bb_leftsib;
			__be32		bb_rightsib;
		} s;			/* short form pointers */
		struct	{
			__be64		bb_leftsib;
			__be64		bb_rightsib;
		} l;			/* long form pointers */
	} bb_u;				/* rest */
} xfs_btree_block_t;

/*
 * Generic key, ptr and record wrapper structures.
 *
 * These are disk format structures, and are converted where necessary
 * by the btree specific code that needs to interpret them.
 */
union xfs_btree_ptr {
	__be32			s;	/* short form ptr */
	__be64			l;	/* long form ptr */
};

union xfs_btree_key {
	xfs_bmbt_key_t		bmbt;
	xfs_bmdr_key_t		bmbr;	/* bmbt root block */
	xfs_alloc_key_t		alloc;
	xfs_inobt_key_t		inobt;
};

union xfs_btree_rec {
	xfs_bmbt_rec_t		bmbt;
	xfs_bmdr_rec_t		bmbr;	/* bmbt root block */
	xfs_alloc_rec_t		alloc;
	xfs_inobt_rec_t		inobt;
};

/*
 * For logging record fields.
 */
#define	XFS_BB_MAGIC		0x01
#define	XFS_BB_LEVEL		0x02
#define	XFS_BB_NUMRECS		0x04
#define	XFS_BB_LEFTSIB		0x08
#define	XFS_BB_RIGHTSIB		0x10
#define	XFS_BB_NUM_BITS		5
#define	XFS_BB_ALL_BITS		((1 << XFS_BB_NUM_BITS) - 1)

/*
 * Magic numbers for btree blocks.
 */
extern const __uint32_t	xfs_magics[];

/*
 * Generic stats interface
 */
#define __XFS_BTREE_STATS_INC(type, stat) \
	XFS_STATS_INC(xs_ ## type ## _2_ ## stat)
#define XFS_BTREE_STATS_INC(cur, stat)  \
do {    \
	switch (cur->bc_btnum) {  \
	case XFS_BTNUM_BNO: __XFS_BTREE_STATS_INC(abtb, stat); break;	\
	case XFS_BTNUM_CNT: __XFS_BTREE_STATS_INC(abtc, stat); break;	\
	case XFS_BTNUM_BMAP: __XFS_BTREE_STATS_INC(bmbt, stat); break;	\
	case XFS_BTNUM_INO: __XFS_BTREE_STATS_INC(ibt, stat); break;	\
	case XFS_BTNUM_MAX: ASSERT(0); /* fucking gcc */ ; break;	\
	}       \
} while (0)

#define __XFS_BTREE_STATS_ADD(type, stat, val) \
	XFS_STATS_ADD(xs_ ## type ## _2_ ## stat, val)
#define XFS_BTREE_STATS_ADD(cur, stat, val)  \
do {    \
	switch (cur->bc_btnum) {  \
	case XFS_BTNUM_BNO: __XFS_BTREE_STATS_ADD(abtb, stat, val); break; \
	case XFS_BTNUM_CNT: __XFS_BTREE_STATS_ADD(abtc, stat, val); break; \
	case XFS_BTNUM_BMAP: __XFS_BTREE_STATS_ADD(bmbt, stat, val); break; \
	case XFS_BTNUM_INO: __XFS_BTREE_STATS_ADD(ibt, stat, val); break; \
	case XFS_BTNUM_MAX: ASSERT(0); /* fucking gcc */ ; break;	\
	}       \
} while (0)
/*
 * Maximum and minimum records in a btree block.
 * Given block size, type prefix, and leaf flag (0 or 1).
 * The divisor below is equivalent to lf ? (e1) : (e2) but that produces
 * compiler warnings.
 */
#define	XFS_BTREE_BLOCK_MAXRECS(bsz,t,lf)	\
	((int)(((bsz) - (uint)sizeof(t ## _block_t)) / \
	 (((lf) * (uint)sizeof(t ## _rec_t)) + \
	  ((1 - (lf)) * \
	   ((uint)sizeof(t ## _key_t) + (uint)sizeof(t ## _ptr_t))))))
#define	XFS_BTREE_BLOCK_MINRECS(bsz,t,lf)	\
	(XFS_BTREE_BLOCK_MAXRECS(bsz,t,lf) / 2)

/*
 * Record, key, and pointer address calculation macros.
 * Given block size, type prefix, block pointer, and index of requested entry
 * (first entry numbered 1).
 */
#define	XFS_BTREE_REC_ADDR(t,bb,i)	\
	((t ## _rec_t *)((char *)(bb) + sizeof(t ## _block_t) + \
	 ((i) - 1) * sizeof(t ## _rec_t)))
#define	XFS_BTREE_KEY_ADDR(t,bb,i)	\
	((t ## _key_t *)((char *)(bb) + sizeof(t ## _block_t) + \
	 ((i) - 1) * sizeof(t ## _key_t)))
#define	XFS_BTREE_PTR_ADDR(t,bb,i,mxr)	\
	((t ## _ptr_t *)((char *)(bb) + sizeof(t ## _block_t) + \
	 (mxr) * sizeof(t ## _key_t) + ((i) - 1) * sizeof(t ## _ptr_t)))

#define	XFS_BTREE_MAXLEVELS	8	/* max of all btrees */

struct xfs_btree_ops {
	/* cursor operations */
	struct xfs_btree_cur *(*dup_cursor)(struct xfs_btree_cur *);

	/* btree tracing */
#ifdef XFS_BTREE_TRACE
	void		(*trace_enter)(struct xfs_btree_cur *, const char *,
				       char *, int, int, __psunsigned_t,
				       __psunsigned_t, __psunsigned_t,
				       __psunsigned_t, __psunsigned_t,
				       __psunsigned_t, __psunsigned_t,
				       __psunsigned_t, __psunsigned_t,
				       __psunsigned_t, __psunsigned_t);
	void		(*trace_cursor)(struct xfs_btree_cur *, __uint32_t *,
					__uint64_t *, __uint64_t *);
	void		(*trace_key)(struct xfs_btree_cur *,
				     union xfs_btree_key *, __uint64_t *,
				     __uint64_t *);
	void		(*trace_record)(struct xfs_btree_cur *,
					union xfs_btree_rec *, __uint64_t *,
					__uint64_t *, __uint64_t *);
#endif
};

/*
 * Btree cursor structure.
 * This collects all information needed by the btree code in one place.
 */
typedef struct xfs_btree_cur
{
	struct xfs_trans	*bc_tp;	/* transaction we're in, if any */
	struct xfs_mount	*bc_mp;	/* file system mount struct */
	const struct xfs_btree_ops *bc_ops;
	uint			bc_flags; /* btree features - below */
	union {
		xfs_alloc_rec_incore_t	a;
		xfs_bmbt_irec_t		b;
		xfs_inobt_rec_incore_t	i;
	}		bc_rec;		/* current insert/search record value */
	struct xfs_buf	*bc_bufs[XFS_BTREE_MAXLEVELS];	/* buf ptr per level */
	int		bc_ptrs[XFS_BTREE_MAXLEVELS];	/* key/record # */
	__uint8_t	bc_ra[XFS_BTREE_MAXLEVELS];	/* readahead bits */
#define	XFS_BTCUR_LEFTRA	1	/* left sibling has been read-ahead */
#define	XFS_BTCUR_RIGHTRA	2	/* right sibling has been read-ahead */
	__uint8_t	bc_nlevels;	/* number of levels in the tree */
	__uint8_t	bc_blocklog;	/* log2(blocksize) of btree blocks */
	xfs_btnum_t	bc_btnum;	/* identifies which btree type */
	union {
		struct {			/* needed for BNO, CNT, INO */
			struct xfs_buf	*agbp;	/* agf/agi buffer pointer */
			xfs_agnumber_t	agno;	/* ag number */
		} a;
		struct {			/* needed for BMAP */
			struct xfs_inode *ip;	/* pointer to our inode */
			struct xfs_bmap_free *flist;	/* list to free after */
			xfs_fsblock_t	firstblock;	/* 1st blk allocated */
			int		allocated;	/* count of alloced */
			short		forksize;	/* fork's inode space */
			char		whichfork;	/* data or attr fork */
			char		flags;		/* flags */
#define	XFS_BTCUR_BPRV_WASDEL	1			/* was delayed */
		} b;
	}		bc_private;	/* per-btree type data */
} xfs_btree_cur_t;

/* cursor flags */
#define XFS_BTREE_LONG_PTRS		(1<<0)	/* pointers are 64bits long */
#define XFS_BTREE_ROOT_IN_INODE		(1<<1)	/* root may be variable size */


#define	XFS_BTREE_NOERROR	0
#define	XFS_BTREE_ERROR		1

/*
 * Convert from buffer to btree block header.
 */
#define	XFS_BUF_TO_BLOCK(bp)	((xfs_btree_block_t *)XFS_BUF_PTR(bp))
#define	XFS_BUF_TO_LBLOCK(bp)	((xfs_btree_lblock_t *)XFS_BUF_PTR(bp))
#define	XFS_BUF_TO_SBLOCK(bp)	((xfs_btree_sblock_t *)XFS_BUF_PTR(bp))


#ifdef __KERNEL__

/*
 * Check that long form block header is ok.
 */
int					/* error (0 or EFSCORRUPTED) */
xfs_btree_check_lblock(
	struct xfs_btree_cur	*cur,	/* btree cursor */
	struct xfs_btree_lblock	*block,	/* btree long form block pointer */
	int			level,	/* level of the btree block */
	struct xfs_buf		*bp);	/* buffer containing block, if any */

/*
 * Check that short form block header is ok.
 */
int					/* error (0 or EFSCORRUPTED) */
xfs_btree_check_sblock(
	struct xfs_btree_cur	*cur,	/* btree cursor */
	struct xfs_btree_sblock	*block,	/* btree short form block pointer */
	int			level,	/* level of the btree block */
	struct xfs_buf		*bp);	/* buffer containing block */

/*
 * Check that block header is ok.
 */
int
xfs_btree_check_block(
	struct xfs_btree_cur	*cur,	/* btree cursor */
	struct xfs_btree_block	*block,	/* generic btree block pointer */
	int			level,	/* level of the btree block */
	struct xfs_buf		*bp);	/* buffer containing block, if any */

/*
 * Check that (long) pointer is ok.
 */
int					/* error (0 or EFSCORRUPTED) */
xfs_btree_check_lptr(
	struct xfs_btree_cur	*cur,	/* btree cursor */
	xfs_dfsbno_t		ptr,	/* btree block disk address */
	int			level);	/* btree block level */

#define xfs_btree_check_lptr_disk(cur, ptr, level) \
	xfs_btree_check_lptr(cur, be64_to_cpu(ptr), level)


/*
 * Check that (short) pointer is ok.
 */
int					/* error (0 or EFSCORRUPTED) */
xfs_btree_check_sptr(
	struct xfs_btree_cur	*cur,	/* btree cursor */
	xfs_agblock_t		ptr,	/* btree block disk address */
	int			level);	/* btree block level */

/*
 * Check that (short) pointer is ok.
 */
int					/* error (0 or EFSCORRUPTED) */
xfs_btree_check_ptr(
	struct xfs_btree_cur	*cur,	/* btree cursor */
	union xfs_btree_ptr	*ptr,	/* btree block disk address */
	int			index,	/* offset from ptr to check */
	int			level);	/* btree block level */

#ifdef DEBUG

/*
 * Debug routine: check that keys are in the right order.
 */
void
xfs_btree_check_key(
	xfs_btnum_t		btnum,	/* btree identifier */
	void			*ak1,	/* pointer to left (lower) key */
	void			*ak2);	/* pointer to right (higher) key */

/*
 * Debug routine: check that records are in the right order.
 */
void
xfs_btree_check_rec(
	xfs_btnum_t		btnum,	/* btree identifier */
	void			*ar1,	/* pointer to left (lower) record */
	void			*ar2);	/* pointer to right (higher) record */
#else
#define	xfs_btree_check_key(a, b, c)
#define	xfs_btree_check_rec(a, b, c)
#endif	/* DEBUG */

/*
 * Delete the btree cursor.
 */
void
xfs_btree_del_cursor(
	xfs_btree_cur_t		*cur,	/* btree cursor */
	int			error);	/* del because of error */

/*
 * Duplicate the btree cursor.
 * Allocate a new one, copy the record, re-get the buffers.
 */
int					/* error */
xfs_btree_dup_cursor(
	xfs_btree_cur_t		*cur,	/* input cursor */
	xfs_btree_cur_t		**ncur);/* output cursor */

/*
 * Change the cursor to point to the first record in the current block
 * at the given level.  Other levels are unaffected.
 */
int					/* success=1, failure=0 */
xfs_btree_firstrec(
	xfs_btree_cur_t		*cur,	/* btree cursor */
	int			level);	/* level to change */

/*
 * Get a buffer for the block, return it with no data read.
 * Long-form addressing.
 */
struct xfs_buf *				/* buffer for fsbno */
xfs_btree_get_bufl(
	struct xfs_mount	*mp,	/* file system mount point */
	struct xfs_trans	*tp,	/* transaction pointer */
	xfs_fsblock_t		fsbno,	/* file system block number */
	uint			lock);	/* lock flags for get_buf */

/*
 * Get a buffer for the block, return it with no data read.
 * Short-form addressing.
 */
struct xfs_buf *				/* buffer for agno/agbno */
xfs_btree_get_bufs(
	struct xfs_mount	*mp,	/* file system mount point */
	struct xfs_trans	*tp,	/* transaction pointer */
	xfs_agnumber_t		agno,	/* allocation group number */
	xfs_agblock_t		agbno,	/* allocation group block number */
	uint			lock);	/* lock flags for get_buf */

/*
 * Check for the cursor referring to the last block at the given level.
 */
int					/* 1=is last block, 0=not last block */
xfs_btree_islastblock(
	xfs_btree_cur_t		*cur,	/* btree cursor */
	int			level);	/* level to check */

/*
 * Change the cursor to point to the last record in the current block
 * at the given level.  Other levels are unaffected.
 */
int					/* success=1, failure=0 */
xfs_btree_lastrec(
	xfs_btree_cur_t		*cur,	/* btree cursor */
	int			level);	/* level to change */

/*
 * Compute first and last byte offsets for the fields given.
 * Interprets the offsets table, which contains struct field offsets.
 */
void
xfs_btree_offsets(
	__int64_t		fields,	/* bitmask of fields */
	const short		*offsets,/* table of field offsets */
	int			nbits,	/* number of bits to inspect */
	int			*first,	/* output: first byte offset */
	int			*last);	/* output: last byte offset */

/*
 * Get a buffer for the block, return it read in.
 * Long-form addressing.
 */
int					/* error */
xfs_btree_read_bufl(
	struct xfs_mount	*mp,	/* file system mount point */
	struct xfs_trans	*tp,	/* transaction pointer */
	xfs_fsblock_t		fsbno,	/* file system block number */
	uint			lock,	/* lock flags for read_buf */
	struct xfs_buf		**bpp,	/* buffer for fsbno */
	int			refval);/* ref count value for buffer */

/*
 * Get a buffer for the block, return it read in.
 * Short-form addressing.
 */
int					/* error */
xfs_btree_read_bufs(
	struct xfs_mount	*mp,	/* file system mount point */
	struct xfs_trans	*tp,	/* transaction pointer */
	xfs_agnumber_t		agno,	/* allocation group number */
	xfs_agblock_t		agbno,	/* allocation group block number */
	uint			lock,	/* lock flags for read_buf */
	struct xfs_buf		**bpp,	/* buffer for agno/agbno */
	int			refval);/* ref count value for buffer */

/*
 * Read-ahead the block, don't wait for it, don't return a buffer.
 * Long-form addressing.
 */
void					/* error */
xfs_btree_reada_bufl(
	struct xfs_mount	*mp,	/* file system mount point */
	xfs_fsblock_t		fsbno,	/* file system block number */
	xfs_extlen_t		count);	/* count of filesystem blocks */

/*
 * Read-ahead the block, don't wait for it, don't return a buffer.
 * Short-form addressing.
 */
void					/* error */
xfs_btree_reada_bufs(
	struct xfs_mount	*mp,	/* file system mount point */
	xfs_agnumber_t		agno,	/* allocation group number */
	xfs_agblock_t		agbno,	/* allocation group block number */
	xfs_extlen_t		count);	/* count of filesystem blocks */

/*
 * Read-ahead btree blocks, at the given level.
 * Bits in lr are set from XFS_BTCUR_{LEFT,RIGHT}RA.
 */
int					/* readahead block count */
xfs_btree_readahead(
	xfs_btree_cur_t		*cur,	/* btree cursor */
	int			lev,	/* level in btree */
	int			lr);	/* left/right bits */

/*
 * Set the buffer for level "lev" in the cursor to bp, releasing
 * any previous buffer.
 */
void
xfs_btree_setbuf(
	xfs_btree_cur_t		*cur,	/* btree cursor */
	int			lev,	/* level in btree */
	struct xfs_buf		*bp);	/* new buffer to set */

#endif	/* __KERNEL__ */


/*
 * Min and max functions for extlen, agblock, fileoff, and filblks types.
 */
#define	XFS_EXTLEN_MIN(a,b)	min_t(xfs_extlen_t, (a), (b))
#define	XFS_EXTLEN_MAX(a,b)	max_t(xfs_extlen_t, (a), (b))
#define	XFS_AGBLOCK_MIN(a,b)	min_t(xfs_agblock_t, (a), (b))
#define	XFS_AGBLOCK_MAX(a,b)	max_t(xfs_agblock_t, (a), (b))
#define	XFS_FILEOFF_MIN(a,b)	min_t(xfs_fileoff_t, (a), (b))
#define	XFS_FILEOFF_MAX(a,b)	max_t(xfs_fileoff_t, (a), (b))
#define	XFS_FILBLKS_MIN(a,b)	min_t(xfs_filblks_t, (a), (b))
#define	XFS_FILBLKS_MAX(a,b)	max_t(xfs_filblks_t, (a), (b))

#define	XFS_FSB_SANITY_CHECK(mp,fsb)	\
	(XFS_FSB_TO_AGNO(mp, fsb) < mp->m_sb.sb_agcount && \
		XFS_FSB_TO_AGBNO(mp, fsb) < mp->m_sb.sb_agblocks)

#endif	/* __XFS_BTREE_H__ */
Commit	Line	Data
1da177e4	1	/*
7b718769 NS	2	* Copyright (c) 2000-2001,2005 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_BTREE_H__
	19	#define __XFS_BTREE_H__
	20
	21	struct xfs_buf;
	22	struct xfs_bmap_free;
	23	struct xfs_inode;
	24	struct xfs_mount;
	25	struct xfs_trans;
	26
a8272ce0 DC	27	extern kmem_zone_t *xfs_btree_cur_zone;
a8272ce0 DC	28
1da177e4 LT	29	/*
	30	* This nonsense is to make -wlint happy.
	31	*/
	32	#define XFS_LOOKUP_EQ ((xfs_lookup_t)XFS_LOOKUP_EQi)
	33	#define XFS_LOOKUP_LE ((xfs_lookup_t)XFS_LOOKUP_LEi)
	34	#define XFS_LOOKUP_GE ((xfs_lookup_t)XFS_LOOKUP_GEi)
	35
	36	#define XFS_BTNUM_BNO ((xfs_btnum_t)XFS_BTNUM_BNOi)
	37	#define XFS_BTNUM_CNT ((xfs_btnum_t)XFS_BTNUM_CNTi)
	38	#define XFS_BTNUM_BMAP ((xfs_btnum_t)XFS_BTNUM_BMAPi)
	39	#define XFS_BTNUM_INO ((xfs_btnum_t)XFS_BTNUM_INOi)
	40
	41	/*
	42	* Short form header: space allocation btrees.
	43	*/
16259e7d CH	44	typedef struct xfs_btree_sblock {
	45	__be32 bb_magic; /* magic number for block type */
	46	__be16 bb_level; /* 0 is a leaf */
	47	__be16 bb_numrecs; /* current # of data records */
	48	__be32 bb_leftsib; /* left sibling block or NULLAGBLOCK */
	49	__be32 bb_rightsib; /* right sibling block or NULLAGBLOCK */
1da177e4 LT	50	} xfs_btree_sblock_t;
	51
	52	/*
	53	* Long form header: bmap btrees.
	54	*/
16259e7d CH	55	typedef struct xfs_btree_lblock {
	56	__be32 bb_magic; /* magic number for block type */
	57	__be16 bb_level; /* 0 is a leaf */
	58	__be16 bb_numrecs; /* current # of data records */
	59	__be64 bb_leftsib; /* left sibling block or NULLDFSBNO */
	60	__be64 bb_rightsib; /* right sibling block or NULLDFSBNO */
1da177e4 LT	61	} xfs_btree_lblock_t;
	62
	63	/*
	64	* Combined header and structure, used by common code.
	65	*/
f2277f06	66	typedef struct xfs_btree_block {
16259e7d CH	67	__be32 bb_magic; /* magic number for block type */
	68	__be16 bb_level; /* 0 is a leaf */
	69	__be16 bb_numrecs; /* current # of data records */
16259e7d CH	70	union {
	71	struct {
	72	__be32 bb_leftsib;
	73	__be32 bb_rightsib;
	74	} s; /* short form pointers */
1da177e4	75	struct {
16259e7d CH	76	__be64 bb_leftsib;
	77	__be64 bb_rightsib;
	78	} l; /* long form pointers */
	79	} bb_u; /* rest */
1da177e4 LT	80	} xfs_btree_block_t;
1da177e4 LT	81
de227dd9 CH	82	/*
	83	* Generic key, ptr and record wrapper structures.
	84	*
	85	* These are disk format structures, and are converted where necessary
	86	* by the btree specific code that needs to interpret them.
	87	*/
	88	union xfs_btree_ptr {
	89	__be32 s; /* short form ptr */
	90	__be64 l; /* long form ptr */
	91	};
	92
	93	union xfs_btree_key {
	94	xfs_bmbt_key_t bmbt;
	95	xfs_bmdr_key_t bmbr; /* bmbt root block */
	96	xfs_alloc_key_t alloc;
	97	xfs_inobt_key_t inobt;
	98	};
	99
	100	union xfs_btree_rec {
	101	xfs_bmbt_rec_t bmbt;
	102	xfs_bmdr_rec_t bmbr; /* bmbt root block */
	103	xfs_alloc_rec_t alloc;
	104	xfs_inobt_rec_t inobt;
	105	};
	106
1da177e4 LT	107	/*
	108	* For logging record fields.
	109	*/
	110	#define XFS_BB_MAGIC 0x01
	111	#define XFS_BB_LEVEL 0x02
	112	#define XFS_BB_NUMRECS 0x04
	113	#define XFS_BB_LEFTSIB 0x08
	114	#define XFS_BB_RIGHTSIB 0x10
	115	#define XFS_BB_NUM_BITS 5
	116	#define XFS_BB_ALL_BITS ((1 << XFS_BB_NUM_BITS) - 1)
	117
1da177e4 LT	118	/*
	119	* Magic numbers for btree blocks.
	120	*/
	121	extern const __uint32_t xfs_magics[];
	122
854929f0 DC	123	/*
	124	* Generic stats interface
	125	*/
	126	#define __XFS_BTREE_STATS_INC(type, stat) \
	127	XFS_STATS_INC(xs_ ## type ## _2_ ## stat)
	128	#define XFS_BTREE_STATS_INC(cur, stat) \
	129	do { \
	130	switch (cur->bc_btnum) { \
	131	case XFS_BTNUM_BNO: __XFS_BTREE_STATS_INC(abtb, stat); break; \
	132	case XFS_BTNUM_CNT: __XFS_BTREE_STATS_INC(abtc, stat); break; \
	133	case XFS_BTNUM_BMAP: __XFS_BTREE_STATS_INC(bmbt, stat); break; \
	134	case XFS_BTNUM_INO: __XFS_BTREE_STATS_INC(ibt, stat); break; \
	135	case XFS_BTNUM_MAX: ASSERT(0); /* fucking gcc */ ; break; \
	136	} \
	137	} while (0)
	138
	139	#define __XFS_BTREE_STATS_ADD(type, stat, val) \
	140	XFS_STATS_ADD(xs_ ## type ## _2_ ## stat, val)
	141	#define XFS_BTREE_STATS_ADD(cur, stat, val) \
	142	do { \
	143	switch (cur->bc_btnum) { \
	144	case XFS_BTNUM_BNO: __XFS_BTREE_STATS_ADD(abtb, stat, val); break; \
	145	case XFS_BTNUM_CNT: __XFS_BTREE_STATS_ADD(abtc, stat, val); break; \
	146	case XFS_BTNUM_BMAP: __XFS_BTREE_STATS_ADD(bmbt, stat, val); break; \
	147	case XFS_BTNUM_INO: __XFS_BTREE_STATS_ADD(ibt, stat, val); break; \
	148	case XFS_BTNUM_MAX: ASSERT(0); /* fucking gcc */ ; break; \
	149	} \
	150	} while (0)
1da177e4 LT	151	/*
	152	* Maximum and minimum records in a btree block.
	153	* Given block size, type prefix, and leaf flag (0 or 1).
	154	* The divisor below is equivalent to lf ? (e1) : (e2) but that produces
	155	* compiler warnings.
	156	*/
	157	#define XFS_BTREE_BLOCK_MAXRECS(bsz,t,lf) \
	158	((int)(((bsz) - (uint)sizeof(t ## _block_t)) / \
	159	(((lf) * (uint)sizeof(t ## _rec_t)) + \
	160	((1 - (lf)) * \
	161	((uint)sizeof(t ## _key_t) + (uint)sizeof(t ## _ptr_t))))))
	162	#define XFS_BTREE_BLOCK_MINRECS(bsz,t,lf) \
	163	(XFS_BTREE_BLOCK_MAXRECS(bsz,t,lf) / 2)
	164
	165	/*
	166	* Record, key, and pointer address calculation macros.
	167	* Given block size, type prefix, block pointer, and index of requested entry
	168	* (first entry numbered 1).
	169	*/
2c36dded	170	#define XFS_BTREE_REC_ADDR(t,bb,i) \
1da177e4 LT	171	((t ## _rec_t )((char )(bb) + sizeof(t ## _block_t) + \
1da177e4 LT	172	((i) - 1) * sizeof(t ## _rec_t)))
2c36dded	173	#define XFS_BTREE_KEY_ADDR(t,bb,i) \
1da177e4 LT	174	((t ## _key_t )((char )(bb) + sizeof(t ## _block_t) + \
1da177e4 LT	175	((i) - 1) * sizeof(t ## _key_t)))
2c36dded	176	#define XFS_BTREE_PTR_ADDR(t,bb,i,mxr) \
1da177e4 LT	177	((t ## _ptr_t )((char )(bb) + sizeof(t ## _block_t) + \
	178	(mxr) * sizeof(t ## _key_t) + ((i) - 1) * sizeof(t ## _ptr_t)))
	179
	180	#define XFS_BTREE_MAXLEVELS 8 /* max of all btrees */
	181
561f7d17 CH	182	struct xfs_btree_ops {
	183	/* cursor operations */
	184	struct xfs_btree_cur (dup_cursor)(struct xfs_btree_cur *);
8c4ed633 CH	185
	186	/* btree tracing */
	187	#ifdef XFS_BTREE_TRACE
	188	void (trace_enter)(struct xfs_btree_cur , const char *,
	189	char *, int, int, __psunsigned_t,
	190	__psunsigned_t, __psunsigned_t,
	191	__psunsigned_t, __psunsigned_t,
	192	__psunsigned_t, __psunsigned_t,
	193	__psunsigned_t, __psunsigned_t,
	194	__psunsigned_t, __psunsigned_t);
	195	void (trace_cursor)(struct xfs_btree_cur , __uint32_t *,
	196	__uint64_t , __uint64_t );
	197	void (trace_key)(struct xfs_btree_cur ,
	198	union xfs_btree_key , __uint64_t ,
	199	__uint64_t *);
	200	void (trace_record)(struct xfs_btree_cur ,
	201	union xfs_btree_rec , __uint64_t ,
	202	__uint64_t , __uint64_t );
	203	#endif
561f7d17 CH	204	};
561f7d17 CH	205
1da177e4 LT	206	/*
	207	* Btree cursor structure.
	208	* This collects all information needed by the btree code in one place.
	209	*/
	210	typedef struct xfs_btree_cur
	211	{
	212	struct xfs_trans bc_tp; / transaction we're in, if any */
	213	struct xfs_mount bc_mp; / file system mount struct */
561f7d17	214	const struct xfs_btree_ops *bc_ops;
8186e517	215	uint bc_flags; /* btree features - below */
1da177e4	216	union {
16259e7d	217	xfs_alloc_rec_incore_t a;
1da177e4	218	xfs_bmbt_irec_t b;
61a25848	219	xfs_inobt_rec_incore_t i;
1da177e4 LT	220	} bc_rec; /* current insert/search record value */
	221	struct xfs_buf bc_bufs[XFS_BTREE_MAXLEVELS]; / buf ptr per level */
	222	int bc_ptrs[XFS_BTREE_MAXLEVELS]; /* key/record # */
	223	__uint8_t bc_ra[XFS_BTREE_MAXLEVELS]; /* readahead bits */
	224	#define XFS_BTCUR_LEFTRA 1 /* left sibling has been read-ahead */
	225	#define XFS_BTCUR_RIGHTRA 2 /* right sibling has been read-ahead */
	226	__uint8_t bc_nlevels; /* number of levels in the tree */
	227	__uint8_t bc_blocklog; /* log2(blocksize) of btree blocks */
	228	xfs_btnum_t bc_btnum; /* identifies which btree type */
	229	union {
169d6227 CH	230	struct { /* needed for BNO, CNT, INO */
169d6227 CH	231	struct xfs_buf agbp; / agf/agi buffer pointer */
1da177e4 LT	232	xfs_agnumber_t agno; /* ag number */
	233	} a;
	234	struct { /* needed for BMAP */
	235	struct xfs_inode ip; / pointer to our inode */
	236	struct xfs_bmap_free flist; / list to free after */
	237	xfs_fsblock_t firstblock; /* 1st blk allocated */
	238	int allocated; /* count of alloced */
	239	short forksize; /* fork's inode space */
	240	char whichfork; /* data or attr fork */
	241	char flags; /* flags */
	242	#define XFS_BTCUR_BPRV_WASDEL 1 /* was delayed */
	243	} b;
1da177e4 LT	244	} bc_private; /* per-btree type data */
	245	} xfs_btree_cur_t;
	246
8186e517	247	/* cursor flags */
e99ab90d	248	#define XFS_BTREE_LONG_PTRS (1<<0) /* pointers are 64bits long */
8186e517 CH	249	#define XFS_BTREE_ROOT_IN_INODE (1<<1) /* root may be variable size */
	250
	251
1da177e4 LT	252	#define XFS_BTREE_NOERROR 0
	253	#define XFS_BTREE_ERROR 1
	254
	255	/*
	256	* Convert from buffer to btree block header.
	257	*/
a844f451 NS	258	#define XFS_BUF_TO_BLOCK(bp) ((xfs_btree_block_t *)XFS_BUF_PTR(bp))
	259	#define XFS_BUF_TO_LBLOCK(bp) ((xfs_btree_lblock_t *)XFS_BUF_PTR(bp))
	260	#define XFS_BUF_TO_SBLOCK(bp) ((xfs_btree_sblock_t *)XFS_BUF_PTR(bp))
	261
1da177e4 LT	262
	263	#ifdef __KERNEL__
	264
1da177e4	265	/*
a23f6ef8	266	* Check that long form block header is ok.
1da177e4	267	*/
a23f6ef8 CH	268	int /* error (0 or EFSCORRUPTED) */
	269	xfs_btree_check_lblock(
	270	struct xfs_btree_cur cur, / btree cursor */
	271	struct xfs_btree_lblock block, / btree long form block pointer */
1da177e4 LT	272	int level, /* level of the btree block */
	273	struct xfs_buf bp); / buffer containing block, if any */
	274
	275	/*
a23f6ef8	276	* Check that short form block header is ok.
1da177e4	277	*/
a23f6ef8 CH	278	int /* error (0 or EFSCORRUPTED) */
	279	xfs_btree_check_sblock(
	280	struct xfs_btree_cur cur, / btree cursor */
	281	struct xfs_btree_sblock block, / btree short form block pointer */
	282	int level, /* level of the btree block */
	283	struct xfs_buf bp); / buffer containing block */
1da177e4 LT	284
1da177e4 LT	285	/*
a23f6ef8	286	* Check that block header is ok.
1da177e4	287	*/
a23f6ef8 CH	288	int
	289	xfs_btree_check_block(
	290	struct xfs_btree_cur cur, / btree cursor */
	291	struct xfs_btree_block block, / generic btree block pointer */
1da177e4 LT	292	int level, /* level of the btree block */
	293	struct xfs_buf bp); / buffer containing block, if any */
	294
	295	/*
a23f6ef8	296	* Check that (long) pointer is ok.
1da177e4 LT	297	*/
	298	int /* error (0 or EFSCORRUPTED) */
	299	xfs_btree_check_lptr(
a23f6ef8	300	struct xfs_btree_cur cur, / btree cursor */
1da177e4 LT	301	xfs_dfsbno_t ptr, /* btree block disk address */
	302	int level); /* btree block level */
	303
b113bcb8	304	#define xfs_btree_check_lptr_disk(cur, ptr, level) \
576039cf	305	xfs_btree_check_lptr(cur, be64_to_cpu(ptr), level)
b113bcb8	306
a23f6ef8	307
1da177e4	308	/*
a23f6ef8	309	* Check that (short) pointer is ok.
1da177e4 LT	310	*/
1da177e4 LT	311	int /* error (0 or EFSCORRUPTED) */
a23f6ef8 CH	312	xfs_btree_check_sptr(
	313	struct xfs_btree_cur cur, / btree cursor */
	314	xfs_agblock_t ptr, /* btree block disk address */
	315	int level); /* btree block level */
1da177e4 LT	316
1da177e4 LT	317	/*
a23f6ef8	318	* Check that (short) pointer is ok.
1da177e4 LT	319	*/
1da177e4 LT	320	int /* error (0 or EFSCORRUPTED) */
a23f6ef8 CH	321	xfs_btree_check_ptr(
	322	struct xfs_btree_cur cur, / btree cursor */
	323	union xfs_btree_ptr ptr, / btree block disk address */
	324	int index, /* offset from ptr to check */
1da177e4 LT	325	int level); /* btree block level */
1da177e4 LT	326
a23f6ef8 CH	327	#ifdef DEBUG
	328
	329	/*
	330	* Debug routine: check that keys are in the right order.
	331	*/
	332	void
	333	xfs_btree_check_key(
	334	xfs_btnum_t btnum, /* btree identifier */
	335	void ak1, / pointer to left (lower) key */
	336	void ak2); / pointer to right (higher) key */
	337
	338	/*
	339	* Debug routine: check that records are in the right order.
	340	*/
	341	void
	342	xfs_btree_check_rec(
	343	xfs_btnum_t btnum, /* btree identifier */
	344	void ar1, / pointer to left (lower) record */
	345	void ar2); / pointer to right (higher) record */
	346	#else
	347	#define xfs_btree_check_key(a, b, c)
	348	#define xfs_btree_check_rec(a, b, c)
	349	#endif /* DEBUG */
	350
1da177e4 LT	351	/*
	352	* Delete the btree cursor.
	353	*/
	354	void
	355	xfs_btree_del_cursor(
	356	xfs_btree_cur_t cur, / btree cursor */
	357	int error); /* del because of error */
	358
	359	/*
	360	* Duplicate the btree cursor.
	361	* Allocate a new one, copy the record, re-get the buffers.
	362	*/
	363	int /* error */
	364	xfs_btree_dup_cursor(
	365	xfs_btree_cur_t cur, / input cursor */
	366	xfs_btree_cur_t *ncur);/ output cursor */
	367
	368	/*
	369	* Change the cursor to point to the first record in the current block
	370	* at the given level. Other levels are unaffected.
	371	*/
	372	int /* success=1, failure=0 */
	373	xfs_btree_firstrec(
	374	xfs_btree_cur_t cur, / btree cursor */
	375	int level); /* level to change */
	376
1da177e4 LT	377	/*
	378	* Get a buffer for the block, return it with no data read.
	379	* Long-form addressing.
	380	*/
	381	struct xfs_buf * /* buffer for fsbno */
	382	xfs_btree_get_bufl(
	383	struct xfs_mount mp, / file system mount point */
	384	struct xfs_trans tp, / transaction pointer */
	385	xfs_fsblock_t fsbno, /* file system block number */
	386	uint lock); /* lock flags for get_buf */
	387
	388	/*
	389	* Get a buffer for the block, return it with no data read.
	390	* Short-form addressing.
	391	*/
	392	struct xfs_buf * /* buffer for agno/agbno */
	393	xfs_btree_get_bufs(
	394	struct xfs_mount mp, / file system mount point */
	395	struct xfs_trans tp, / transaction pointer */
	396	xfs_agnumber_t agno, /* allocation group number */
	397	xfs_agblock_t agbno, /* allocation group block number */
	398	uint lock); /* lock flags for get_buf */
	399
1da177e4 LT	400	/*
	401	* Check for the cursor referring to the last block at the given level.
	402	*/
	403	int /* 1=is last block, 0=not last block */
	404	xfs_btree_islastblock(
	405	xfs_btree_cur_t cur, / btree cursor */
	406	int level); /* level to check */
	407
	408	/*
	409	* Change the cursor to point to the last record in the current block
	410	* at the given level. Other levels are unaffected.
	411	*/
	412	int /* success=1, failure=0 */
	413	xfs_btree_lastrec(
	414	xfs_btree_cur_t cur, / btree cursor */
	415	int level); /* level to change */
	416
	417	/*
	418	* Compute first and last byte offsets for the fields given.
	419	* Interprets the offsets table, which contains struct field offsets.
	420	*/
	421	void
	422	xfs_btree_offsets(
	423	__int64_t fields, /* bitmask of fields */
	424	const short offsets,/ table of field offsets */
	425	int nbits, /* number of bits to inspect */
	426	int first, / output: first byte offset */
	427	int last); / output: last byte offset */
	428
	429	/*
	430	* Get a buffer for the block, return it read in.
	431	* Long-form addressing.
	432	*/
	433	int /* error */
	434	xfs_btree_read_bufl(
	435	struct xfs_mount mp, / file system mount point */
	436	struct xfs_trans tp, / transaction pointer */
	437	xfs_fsblock_t fsbno, /* file system block number */
	438	uint lock, /* lock flags for read_buf */
	439	struct xfs_buf *bpp, / buffer for fsbno */
	440	int refval);/* ref count value for buffer */
	441
	442	/*
	443	* Get a buffer for the block, return it read in.
	444	* Short-form addressing.
	445	*/
	446	int /* error */
	447	xfs_btree_read_bufs(
	448	struct xfs_mount mp, / file system mount point */
	449	struct xfs_trans tp, / transaction pointer */
	450	xfs_agnumber_t agno, /* allocation group number */
	451	xfs_agblock_t agbno, /* allocation group block number */
	452	uint lock, /* lock flags for read_buf */
	453	struct xfs_buf *bpp, / buffer for agno/agbno */
	454	int refval);/* ref count value for buffer */
	455
	456	/*
	457	* Read-ahead the block, don't wait for it, don't return a buffer.
	458	* Long-form addressing.
	459	*/
	460	void /* error */
	461	xfs_btree_reada_bufl(
	462	struct xfs_mount mp, / file system mount point */
	463	xfs_fsblock_t fsbno, /* file system block number */
464	xfs_extlen_t count); /* count of filesystem blocks */
465
466	/*
467	* Read-ahead the block, don't wait for it, don't return a buffer.
468	* Short-form addressing.
469	*/
470	void /* error */
471	xfs_btree_reada_bufs(
472	struct xfs_mount mp, / file system mount point */
473	xfs_agnumber_t agno, /* allocation group number */
474	xfs_agblock_t agbno, /* allocation group block number */
475	xfs_extlen_t count); /* count of filesystem blocks */
476
477	/*
478	* Read-ahead btree blocks, at the given level.
479	* Bits in lr are set from XFS_BTCUR_{LEFT,RIGHT}RA.
480	*/
481	int /* readahead block count */
1da177e4 LT	482	xfs_btree_readahead(
	483	xfs_btree_cur_t cur, / btree cursor */
	484	int lev, /* level in btree */
b524bfee	485	int lr); /* left/right bits */
1da177e4 LT	486
	487	/*
	488	* Set the buffer for level "lev" in the cursor to bp, releasing
	489	* any previous buffer.
	490	*/
	491	void
	492	xfs_btree_setbuf(
	493	xfs_btree_cur_t cur, / btree cursor */
	494	int lev, /* level in btree */
	495	struct xfs_buf bp); / new buffer to set */
	496
	497	#endif /* __KERNEL__ */
	498
	499
	500	/*
	501	* Min and max functions for extlen, agblock, fileoff, and filblks types.
	502	*/
54aa8e26 DC	503	#define XFS_EXTLEN_MIN(a,b) min_t(xfs_extlen_t, (a), (b))
	504	#define XFS_EXTLEN_MAX(a,b) max_t(xfs_extlen_t, (a), (b))
	505	#define XFS_AGBLOCK_MIN(a,b) min_t(xfs_agblock_t, (a), (b))
	506	#define XFS_AGBLOCK_MAX(a,b) max_t(xfs_agblock_t, (a), (b))
	507	#define XFS_FILEOFF_MIN(a,b) min_t(xfs_fileoff_t, (a), (b))
	508	#define XFS_FILEOFF_MAX(a,b) max_t(xfs_fileoff_t, (a), (b))
	509	#define XFS_FILBLKS_MIN(a,b) min_t(xfs_filblks_t, (a), (b))
	510	#define XFS_FILBLKS_MAX(a,b) max_t(xfs_filblks_t, (a), (b))
a844f451	511
1da177e4 LT	512	#define XFS_FSB_SANITY_CHECK(mp,fsb) \
1da177e4 LT	513	(XFS_FSB_TO_AGNO(mp, fsb) < mp->m_sb.sb_agcount && \
a844f451	514	XFS_FSB_TO_AGBNO(mp, fsb) < mp->m_sb.sb_agblocks)
1da177e4 LT	515
1da177e4 LT	516	#endif /* __XFS_BTREE_H__ */