[linux.git] / fs / jfs / jfs_dmap.h

/*
 *   Copyright (C) International Business Machines Corp., 2000-2002
 *
 *   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; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will 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 to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */
#ifndef	_H_JFS_DMAP
#define _H_JFS_DMAP

#include "jfs_txnmgr.h"

#define BMAPVERSION	1	/* version number */
#define	TREESIZE	(256+64+16+4+1)	/* size of a dmap tree */
#define	LEAFIND		(64+16+4+1)	/* index of 1st leaf of a dmap tree */
#define LPERDMAP	256	/* num leaves per dmap tree */
#define L2LPERDMAP	8	/* l2 number of leaves per dmap tree */
#define	DBWORD		32	/* # of blks covered by a map word */
#define	L2DBWORD	5	/* l2 # of blks covered by a mword */
#define BUDMIN		L2DBWORD	/* max free string in a map word */
#define BPERDMAP	(LPERDMAP * DBWORD)	/* num of blks per dmap */
#define L2BPERDMAP	13	/* l2 num of blks per dmap */
#define CTLTREESIZE	(1024+256+64+16+4+1)	/* size of a dmapctl tree */
#define CTLLEAFIND	(256+64+16+4+1)	/* idx of 1st leaf of a dmapctl tree */
#define LPERCTL		1024	/* num of leaves per dmapctl tree */
#define L2LPERCTL	10	/* l2 num of leaves per dmapctl tree */
#define	ROOT		0	/* index of the root of a tree */
#define	NOFREE		((s8) -1)	/* no blocks free */
#define	MAXAG		128	/* max number of allocation groups */
#define L2MAXAG		7	/* l2 max num of AG */
#define L2MINAGSZ	25	/* l2 of minimum AG size in bytes */
#define	BMAPBLKNO	0	/* lblkno of bmap within the map */

/*
 * maximum l2 number of disk blocks at the various dmapctl levels.
 */
#define	L2MAXL0SIZE	(L2BPERDMAP + 1 * L2LPERCTL)
#define	L2MAXL1SIZE	(L2BPERDMAP + 2 * L2LPERCTL)
#define	L2MAXL2SIZE	(L2BPERDMAP + 3 * L2LPERCTL)

/*
 * maximum number of disk blocks at the various dmapctl levels.
 */
#define	MAXL0SIZE	((s64)1 << L2MAXL0SIZE)
#define	MAXL1SIZE	((s64)1 << L2MAXL1SIZE)
#define	MAXL2SIZE	((s64)1 << L2MAXL2SIZE)

#define	MAXMAPSIZE	MAXL2SIZE	/* maximum aggregate map size */

/*
 * determine the maximum free string for four (lower level) nodes
 * of the tree.
 */
static inline signed char TREEMAX(signed char *cp)
{
	signed char tmp1, tmp2;

	tmp1 = max(*(cp+2), *(cp+3));
	tmp2 = max(*(cp), *(cp+1));

	return max(tmp1, tmp2);
}

/*
 * convert disk block number to the logical block number of the dmap
 * describing the disk block.  s is the log2(number of logical blocks per page)
 *
 * The calculation figures out how many logical pages are in front of the dmap.
 *	- the number of dmaps preceding it
 *	- the number of L0 pages preceding its L0 page
 *	- the number of L1 pages preceding its L1 page
 *	- 3 is added to account for the L2, L1, and L0 page for this dmap
 *	- 1 is added to account for the control page of the map.
 */
#define BLKTODMAP(b,s)    \
	((((b) >> 13) + ((b) >> 23) + ((b) >> 33) + 3 + 1) << (s))

/*
 * convert disk block number to the logical block number of the LEVEL 0
 * dmapctl describing the disk block.  s is the log2(number of logical blocks
 * per page)
 *
 * The calculation figures out how many logical pages are in front of the L0.
 *	- the number of dmap pages preceding it
 *	- the number of L0 pages preceding it
 *	- the number of L1 pages preceding its L1 page
 *	- 2 is added to account for the L2, and L1 page for this L0
 *	- 1 is added to account for the control page of the map.
 */
#define BLKTOL0(b,s)      \
	(((((b) >> 23) << 10) + ((b) >> 23) + ((b) >> 33) + 2 + 1) << (s))

/*
 * convert disk block number to the logical block number of the LEVEL 1
 * dmapctl describing the disk block.  s is the log2(number of logical blocks
 * per page)
 *
 * The calculation figures out how many logical pages are in front of the L1.
 *	- the number of dmap pages preceding it
 *	- the number of L0 pages preceding it
 *	- the number of L1 pages preceding it
 *	- 1 is added to account for the L2 page
 *	- 1 is added to account for the control page of the map.
 */
#define BLKTOL1(b,s)      \
     (((((b) >> 33) << 20) + (((b) >> 33) << 10) + ((b) >> 33) + 1 + 1) << (s))

/*
 * convert disk block number to the logical block number of the dmapctl
 * at the specified level which describes the disk block.
 */
#define BLKTOCTL(b,s,l)   \
	(((l) == 2) ? 1 : ((l) == 1) ? BLKTOL1((b),(s)) : BLKTOL0((b),(s)))

/*
 * convert aggregate map size to the zero origin dmapctl level of the
 * top dmapctl.
 */
#define	BMAPSZTOLEV(size)	\
	(((size) <= MAXL0SIZE) ? 0 : ((size) <= MAXL1SIZE) ? 1 : 2)

/* convert disk block number to allocation group number.
 */
#define BLKTOAG(b,sbi)	((b) >> ((sbi)->bmap->db_agl2size))

/* convert allocation group number to starting disk block
 * number.
 */
#define AGTOBLK(a,ip)	\
	((s64)(a) << (JFS_SBI((ip)->i_sb)->bmap->db_agl2size))

/*
 *	dmap summary tree
 *
 * dmaptree must be consistent with dmapctl.
 */
struct dmaptree {
	__le32 nleafs;		/* 4: number of tree leafs	*/
	__le32 l2nleafs;	/* 4: l2 number of tree leafs	*/
	__le32 leafidx;		/* 4: index of first tree leaf	*/
	__le32 height;		/* 4: height of the tree	*/
	s8 budmin;		/* 1: min l2 tree leaf value to combine */
	s8 stree[TREESIZE];	/* TREESIZE: tree		*/
	u8 pad[2];		/* 2: pad to word boundary	*/
};				/* - 360 -			*/

/*
 *	dmap page per 8K blocks bitmap
 */
struct dmap {
	__le32 nblocks;		/* 4: num blks covered by this dmap	*/
	__le32 nfree;		/* 4: num of free blks in this dmap	*/
	__le64 start;		/* 8: starting blkno for this dmap	*/
	struct dmaptree tree;	/* 360: dmap tree			*/
	u8 pad[1672];		/* 1672: pad to 2048 bytes		*/
	__le32 wmap[LPERDMAP];	/* 1024: bits of the working map	*/
	__le32 pmap[LPERDMAP];	/* 1024: bits of the persistent map	*/
};				/* - 4096 -				*/

/*
 *	disk map control page per level.
 *
 * dmapctl must be consistent with dmaptree.
 */
struct dmapctl {
	__le32 nleafs;		/* 4: number of tree leafs	*/
	__le32 l2nleafs;	/* 4: l2 number of tree leafs	*/
	__le32 leafidx;		/* 4: index of the first tree leaf	*/
	__le32 height;		/* 4: height of tree		*/
	s8 budmin;		/* 1: minimum l2 tree leaf value	*/
	s8 stree[CTLTREESIZE];	/* CTLTREESIZE: dmapctl tree	*/
	u8 pad[2714];		/* 2714: pad to 4096		*/
};				/* - 4096 -			*/

/*
 *	common definition for dmaptree within dmap and dmapctl
 */
typedef union dmtree {
	struct dmaptree t1;
	struct dmapctl t2;
} dmtree_t;

/* macros for accessing fields within dmtree */
#define	dmt_nleafs	t1.nleafs
#define	dmt_l2nleafs	t1.l2nleafs
#define	dmt_leafidx	t1.leafidx
#define	dmt_height	t1.height
#define	dmt_budmin	t1.budmin
#define	dmt_stree	t1.stree

/*
 *	on-disk aggregate disk allocation map descriptor.
 */
struct dbmap_disk {
	__le64 dn_mapsize;	/* 8: number of blocks in aggregate	*/
	__le64 dn_nfree;	/* 8: num free blks in aggregate map	*/
	__le32 dn_l2nbperpage;	/* 4: number of blks per page		*/
	__le32 dn_numag;	/* 4: total number of ags		*/
	__le32 dn_maxlevel;	/* 4: number of active ags		*/
	__le32 dn_maxag;	/* 4: max active alloc group number	*/
	__le32 dn_agpref;	/* 4: preferred alloc group (hint)	*/
	__le32 dn_aglevel;	/* 4: dmapctl level holding the AG	*/
	__le32 dn_agheight;	/* 4: height in dmapctl of the AG	*/
	__le32 dn_agwidth;	/* 4: width in dmapctl of the AG	*/
	__le32 dn_agstart;	/* 4: start tree index at AG height	*/
	__le32 dn_agl2size;	/* 4: l2 num of blks per alloc group	*/
	__le64 dn_agfree[MAXAG];/* 8*MAXAG: per AG free count		*/
	__le64 dn_agsize;	/* 8: num of blks per alloc group	*/
	s8 dn_maxfreebud;	/* 1: max free buddy system		*/
	u8 pad[3007];		/* 3007: pad to 4096			*/
};				/* - 4096 -				*/

struct dbmap {
	s64 dn_mapsize;		/* number of blocks in aggregate	*/
	s64 dn_nfree;		/* num free blks in aggregate map	*/
	int dn_l2nbperpage;	/* number of blks per page		*/
	int dn_numag;		/* total number of ags			*/
	int dn_maxlevel;	/* number of active ags			*/
	int dn_maxag;		/* max active alloc group number	*/
	int dn_agpref;		/* preferred alloc group (hint)		*/
	int dn_aglevel;		/* dmapctl level holding the AG		*/
	int dn_agheight;	/* height in dmapctl of the AG		*/
	int dn_agwidth;		/* width in dmapctl of the AG		*/
	int dn_agstart;		/* start tree index at AG height	*/
	int dn_agl2size;	/* l2 num of blks per alloc group	*/
	s64 dn_agfree[MAXAG];	/* per AG free count			*/
	s64 dn_agsize;		/* num of blks per alloc group		*/
	signed char dn_maxfreebud;	/* max free buddy system	*/
};				/* - 4096 -				*/
/*
 *	in-memory aggregate disk allocation map descriptor.
 */
struct bmap {
	struct dbmap db_bmap;		/* on-disk aggregate map descriptor */
	struct inode *db_ipbmap;	/* ptr to aggregate map incore inode */
	struct mutex db_bmaplock;	/* aggregate map lock */
	atomic_t db_active[MAXAG];	/* count of active, open files in AG */
	u32 *db_DBmap;
};

/* macros for accessing fields within in-memory aggregate map descriptor */
#define	db_mapsize	db_bmap.dn_mapsize
#define	db_nfree	db_bmap.dn_nfree
#define	db_agfree	db_bmap.dn_agfree
#define	db_agsize	db_bmap.dn_agsize
#define	db_agl2size	db_bmap.dn_agl2size
#define	db_agwidth	db_bmap.dn_agwidth
#define	db_agheight	db_bmap.dn_agheight
#define	db_agstart	db_bmap.dn_agstart
#define	db_numag	db_bmap.dn_numag
#define	db_maxlevel	db_bmap.dn_maxlevel
#define	db_aglevel	db_bmap.dn_aglevel
#define	db_agpref	db_bmap.dn_agpref
#define	db_maxag	db_bmap.dn_maxag
#define	db_maxfreebud	db_bmap.dn_maxfreebud
#define	db_l2nbperpage	db_bmap.dn_l2nbperpage

/*
 * macros for various conversions needed by the allocators.
 * blkstol2(), cntlz(), and cnttz() are operating system dependent functions.
 */
/* convert number of blocks to log2 number of blocks, rounding up to
 * the next log2 value if blocks is not a l2 multiple.
 */
#define	BLKSTOL2(d)		(blkstol2(d))

/* convert number of leafs to log2 leaf value */
#define	NLSTOL2BSZ(n)		(31 - cntlz((n)) + BUDMIN)

/* convert leaf index to log2 leaf value */
#define	LITOL2BSZ(n,m,b)	((((n) == 0) ? (m) : cnttz((n))) + (b))

/* convert a block number to a dmap control leaf index */
#define BLKTOCTLLEAF(b,m)	\
	(((b) & (((s64)1 << ((m) + L2LPERCTL)) - 1)) >> (m))

/* convert log2 leaf value to buddy size */
#define	BUDSIZE(s,m)		(1 << ((s) - (m)))

/*
 *	external references.
 */
extern int dbMount(struct inode *ipbmap);

extern int dbUnmount(struct inode *ipbmap, int mounterror);

extern int dbFree(struct inode *ipbmap, s64 blkno, s64 nblocks);

extern int dbUpdatePMap(struct inode *ipbmap,
			int free, s64 blkno, s64 nblocks, struct tblock * tblk);

extern int dbNextAG(struct inode *ipbmap);

extern int dbAlloc(struct inode *ipbmap, s64 hint, s64 nblocks, s64 * results);

extern int dbReAlloc(struct inode *ipbmap,
		     s64 blkno, s64 nblocks, s64 addnblocks, s64 * results);

extern int dbSync(struct inode *ipbmap);
extern int dbAllocBottomUp(struct inode *ip, s64 blkno, s64 nblocks);
extern int dbExtendFS(struct inode *ipbmap, s64 blkno, s64 nblocks);
extern void dbFinalizeBmap(struct inode *ipbmap);
extern s64 dbMapFileSizeToMapSize(struct inode *ipbmap);
extern s64 dbDiscardAG(struct inode *ip, int agno, s64 minlen);

#endif				/* _H_JFS_DMAP */
Commit	Line	Data
1da177e4	1	/*
63f83c9f	2	* Copyright (C) International Business Machines Corp., 2000-2002
1da177e4 LT	3	*
	4	* This program is free software; you can redistribute it and/or modify
	5	* it under the terms of the GNU General Public License as published by
63f83c9f	6	* the Free Software Foundation; either version 2 of the License, or
1da177e4	7	* (at your option) any later version.
63f83c9f	8	*
1da177e4 LT	9	* This program is distributed in the hope that it will be useful,
	10	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	11	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
	12	* the GNU General Public License for more details.
	13	*
	14	* You should have received a copy of the GNU General Public License
63f83c9f	15	* along with this program; if not, write to the Free Software
1da177e4 LT	16	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	17	*/
	18	#ifndef _H_JFS_DMAP
	19	#define _H_JFS_DMAP
	20
	21	#include "jfs_txnmgr.h"
	22
	23	#define BMAPVERSION 1 /* version number */
	24	#define TREESIZE (256+64+16+4+1) /* size of a dmap tree */
	25	#define LEAFIND (64+16+4+1) /* index of 1st leaf of a dmap tree */
	26	#define LPERDMAP 256 /* num leaves per dmap tree */
	27	#define L2LPERDMAP 8 /* l2 number of leaves per dmap tree */
	28	#define DBWORD 32 /* # of blks covered by a map word */
	29	#define L2DBWORD 5 /* l2 # of blks covered by a mword */
63f83c9f	30	#define BUDMIN L2DBWORD /* max free string in a map word */
1da177e4 LT	31	#define BPERDMAP (LPERDMAP * DBWORD) /* num of blks per dmap */
	32	#define L2BPERDMAP 13 /* l2 num of blks per dmap */
	33	#define CTLTREESIZE (1024+256+64+16+4+1) /* size of a dmapctl tree */
	34	#define CTLLEAFIND (256+64+16+4+1) /* idx of 1st leaf of a dmapctl tree */
	35	#define LPERCTL 1024 /* num of leaves per dmapctl tree */
	36	#define L2LPERCTL 10 /* l2 num of leaves per dmapctl tree */
	37	#define ROOT 0 /* index of the root of a tree */
	38	#define NOFREE ((s8) -1) /* no blocks free */
	39	#define MAXAG 128 /* max number of allocation groups */
	40	#define L2MAXAG 7 /* l2 max num of AG */
	41	#define L2MINAGSZ 25 /* l2 of minimum AG size in bytes */
	42	#define BMAPBLKNO 0 /* lblkno of bmap within the map */
	43
	44	/*
	45	* maximum l2 number of disk blocks at the various dmapctl levels.
	46	*/
	47	#define L2MAXL0SIZE (L2BPERDMAP + 1 * L2LPERCTL)
	48	#define L2MAXL1SIZE (L2BPERDMAP + 2 * L2LPERCTL)
	49	#define L2MAXL2SIZE (L2BPERDMAP + 3 * L2LPERCTL)
	50
	51	/*
	52	* maximum number of disk blocks at the various dmapctl levels.
	53	*/
	54	#define MAXL0SIZE ((s64)1 << L2MAXL0SIZE)
	55	#define MAXL1SIZE ((s64)1 << L2MAXL1SIZE)
	56	#define MAXL2SIZE ((s64)1 << L2MAXL2SIZE)
	57
	58	#define MAXMAPSIZE MAXL2SIZE /* maximum aggregate map size */
	59
63f83c9f	60	/*
1da177e4 LT	61	* determine the maximum free string for four (lower level) nodes
	62	* of the tree.
	63	*/
15732a1c	64	static inline signed char TREEMAX(signed char *cp)
1da177e4 LT	65	{
	66	signed char tmp1, tmp2;
	67
	68	tmp1 = max((cp+2), (cp+3));
	69	tmp2 = max((cp), (cp+1));
	70
	71	return max(tmp1, tmp2);
	72	}
	73
	74	/*
	75	* convert disk block number to the logical block number of the dmap
	76	* describing the disk block. s is the log2(number of logical blocks per page)
	77	*
	78	* The calculation figures out how many logical pages are in front of the dmap.
	79	* - the number of dmaps preceding it
	80	* - the number of L0 pages preceding its L0 page
	81	* - the number of L1 pages preceding its L1 page
	82	* - 3 is added to account for the L2, L1, and L0 page for this dmap
	83	* - 1 is added to account for the control page of the map.
	84	*/
	85	#define BLKTODMAP(b,s) \
f720e3ba	86	((((b) >> 13) + ((b) >> 23) + ((b) >> 33) + 3 + 1) << (s))
1da177e4 LT	87
	88	/*
	89	* convert disk block number to the logical block number of the LEVEL 0
	90	* dmapctl describing the disk block. s is the log2(number of logical blocks
	91	* per page)
	92	*
	93	* The calculation figures out how many logical pages are in front of the L0.
	94	* - the number of dmap pages preceding it
	95	* - the number of L0 pages preceding it
	96	* - the number of L1 pages preceding its L1 page
	97	* - 2 is added to account for the L2, and L1 page for this L0
	98	* - 1 is added to account for the control page of the map.
	99	*/
	100	#define BLKTOL0(b,s) \
f720e3ba	101	(((((b) >> 23) << 10) + ((b) >> 23) + ((b) >> 33) + 2 + 1) << (s))
1da177e4 LT	102
	103	/*
	104	* convert disk block number to the logical block number of the LEVEL 1
	105	* dmapctl describing the disk block. s is the log2(number of logical blocks
	106	* per page)
	107	*
	108	* The calculation figures out how many logical pages are in front of the L1.
	109	* - the number of dmap pages preceding it
	110	* - the number of L0 pages preceding it
	111	* - the number of L1 pages preceding it
	112	* - 1 is added to account for the L2 page
	113	* - 1 is added to account for the control page of the map.
	114	*/
	115	#define BLKTOL1(b,s) \
	116	(((((b) >> 33) << 20) + (((b) >> 33) << 10) + ((b) >> 33) + 1 + 1) << (s))
	117
	118	/*
	119	* convert disk block number to the logical block number of the dmapctl
	120	* at the specified level which describes the disk block.
	121	*/
	122	#define BLKTOCTL(b,s,l) \
f720e3ba	123	(((l) == 2) ? 1 : ((l) == 1) ? BLKTOL1((b),(s)) : BLKTOL0((b),(s)))
1da177e4	124
63f83c9f	125	/*
1da177e4 LT	126	* convert aggregate map size to the zero origin dmapctl level of the
	127	* top dmapctl.
	128	*/
	129	#define BMAPSZTOLEV(size) \
	130	(((size) <= MAXL0SIZE) ? 0 : ((size) <= MAXL1SIZE) ? 1 : 2)
	131
	132	/* convert disk block number to allocation group number.
	133	*/
	134	#define BLKTOAG(b,sbi) ((b) >> ((sbi)->bmap->db_agl2size))
	135
	136	/* convert allocation group number to starting disk block
	137	* number.
	138	*/
	139	#define AGTOBLK(a,ip) \
	140	((s64)(a) << (JFS_SBI((ip)->i_sb)->bmap->db_agl2size))
	141
	142	/*
	143	* dmap summary tree
	144	*
	145	* dmaptree must be consistent with dmapctl.
	146	*/
	147	struct dmaptree {
f720e3ba DK	148	__le32 nleafs; /* 4: number of tree leafs */
	149	__le32 l2nleafs; /* 4: l2 number of tree leafs */
	150	__le32 leafidx; /* 4: index of first tree leaf */
	151	__le32 height; /* 4: height of the tree */
1da177e4	152	s8 budmin; /* 1: min l2 tree leaf value to combine */
f720e3ba DK	153	s8 stree[TREESIZE]; /* TREESIZE: tree */
	154	u8 pad[2]; /* 2: pad to word boundary */
	155	}; /* - 360 - */
1da177e4 LT	156
	157	/*
	158	* dmap page per 8K blocks bitmap
	159	*/
	160	struct dmap {
f720e3ba DK	161	__le32 nblocks; /* 4: num blks covered by this dmap */
	162	__le32 nfree; /* 4: num of free blks in this dmap */
	163	__le64 start; /* 8: starting blkno for this dmap */
	164	struct dmaptree tree; /* 360: dmap tree */
	165	u8 pad[1672]; /* 1672: pad to 2048 bytes */
	166	__le32 wmap[LPERDMAP]; /* 1024: bits of the working map */
	167	__le32 pmap[LPERDMAP]; /* 1024: bits of the persistent map */
	168	}; /* - 4096 - */
1da177e4 LT	169
	170	/*
	171	* disk map control page per level.
	172	*
	173	* dmapctl must be consistent with dmaptree.
	174	*/
	175	struct dmapctl {
f720e3ba DK	176	__le32 nleafs; /* 4: number of tree leafs */
	177	__le32 l2nleafs; /* 4: l2 number of tree leafs */
	178	__le32 leafidx; /* 4: index of the first tree leaf */
	179	__le32 height; /* 4: height of tree */
	180	s8 budmin; /* 1: minimum l2 tree leaf value */
	181	s8 stree[CTLTREESIZE]; /* CTLTREESIZE: dmapctl tree */
	182	u8 pad[2714]; /* 2714: pad to 4096 */
	183	}; /* - 4096 - */
1da177e4 LT	184
	185	/*
	186	* common definition for dmaptree within dmap and dmapctl
	187	*/
	188	typedef union dmtree {
	189	struct dmaptree t1;
	190	struct dmapctl t2;
	191	} dmtree_t;
	192
	193	/* macros for accessing fields within dmtree */
	194	#define dmt_nleafs t1.nleafs
63f83c9f DK	195	#define dmt_l2nleafs t1.l2nleafs
	196	#define dmt_leafidx t1.leafidx
	197	#define dmt_height t1.height
	198	#define dmt_budmin t1.budmin
	199	#define dmt_stree t1.stree
1da177e4	200
63f83c9f	201	/*
1da177e4 LT	202	* on-disk aggregate disk allocation map descriptor.
	203	*/
	204	struct dbmap_disk {
f720e3ba DK	205	__le64 dn_mapsize; /* 8: number of blocks in aggregate */
	206	__le64 dn_nfree; /* 8: num free blks in aggregate map */
	207	__le32 dn_l2nbperpage; /* 4: number of blks per page */
	208	__le32 dn_numag; /* 4: total number of ags */
	209	__le32 dn_maxlevel; /* 4: number of active ags */
	210	__le32 dn_maxag; /* 4: max active alloc group number */
	211	__le32 dn_agpref; /* 4: preferred alloc group (hint) */
	212	__le32 dn_aglevel; /* 4: dmapctl level holding the AG */
d7eecb48	213	__le32 dn_agheight; /* 4: height in dmapctl of the AG */
f720e3ba DK	214	__le32 dn_agwidth; /* 4: width in dmapctl of the AG */
	215	__le32 dn_agstart; /* 4: start tree index at AG height */
	216	__le32 dn_agl2size; /* 4: l2 num of blks per alloc group */
	217	__le64 dn_agfree[MAXAG];/* 8MAXAG: per AG free count /
	218	__le64 dn_agsize; /* 8: num of blks per alloc group */
	219	s8 dn_maxfreebud; /* 1: max free buddy system */
	220	u8 pad[3007]; /* 3007: pad to 4096 */
	221	}; /* - 4096 - */
1da177e4 LT	222
1da177e4 LT	223	struct dbmap {
f720e3ba DK	224	s64 dn_mapsize; /* number of blocks in aggregate */
	225	s64 dn_nfree; /* num free blks in aggregate map */
	226	int dn_l2nbperpage; /* number of blks per page */
	227	int dn_numag; /* total number of ags */
	228	int dn_maxlevel; /* number of active ags */
	229	int dn_maxag; /* max active alloc group number */
	230	int dn_agpref; /* preferred alloc group (hint) */
	231	int dn_aglevel; /* dmapctl level holding the AG */
d7eecb48	232	int dn_agheight; /* height in dmapctl of the AG */
f720e3ba DK	233	int dn_agwidth; /* width in dmapctl of the AG */
	234	int dn_agstart; /* start tree index at AG height */
	235	int dn_agl2size; /* l2 num of blks per alloc group */
	236	s64 dn_agfree[MAXAG]; /* per AG free count */
	237	s64 dn_agsize; /* num of blks per alloc group */
	238	signed char dn_maxfreebud; /* max free buddy system */
	239	}; /* - 4096 - */
63f83c9f	240	/*
1da177e4 LT	241	* in-memory aggregate disk allocation map descriptor.
	242	*/
	243	struct bmap {
	244	struct dbmap db_bmap; /* on-disk aggregate map descriptor */
	245	struct inode db_ipbmap; / ptr to aggregate map incore inode */
1de87444	246	struct mutex db_bmaplock; /* aggregate map lock */
1da177e4 LT	247	atomic_t db_active[MAXAG]; /* count of active, open files in AG */
	248	u32 *db_DBmap;
	249	};
	250
	251	/* macros for accessing fields within in-memory aggregate map descriptor */
	252	#define db_mapsize db_bmap.dn_mapsize
	253	#define db_nfree db_bmap.dn_nfree
	254	#define db_agfree db_bmap.dn_agfree
	255	#define db_agsize db_bmap.dn_agsize
	256	#define db_agl2size db_bmap.dn_agl2size
	257	#define db_agwidth db_bmap.dn_agwidth
d7eecb48	258	#define db_agheight db_bmap.dn_agheight
1da177e4 LT	259	#define db_agstart db_bmap.dn_agstart
	260	#define db_numag db_bmap.dn_numag
	261	#define db_maxlevel db_bmap.dn_maxlevel
	262	#define db_aglevel db_bmap.dn_aglevel
	263	#define db_agpref db_bmap.dn_agpref
	264	#define db_maxag db_bmap.dn_maxag
	265	#define db_maxfreebud db_bmap.dn_maxfreebud
	266	#define db_l2nbperpage db_bmap.dn_l2nbperpage
	267
	268	/*
	269	* macros for various conversions needed by the allocators.
	270	* blkstol2(), cntlz(), and cnttz() are operating system dependent functions.
	271	*/
	272	/* convert number of blocks to log2 number of blocks, rounding up to
	273	* the next log2 value if blocks is not a l2 multiple.
	274	*/
	275	#define BLKSTOL2(d) (blkstol2(d))
	276
	277	/* convert number of leafs to log2 leaf value */
	278	#define NLSTOL2BSZ(n) (31 - cntlz((n)) + BUDMIN)
	279
	280	/* convert leaf index to log2 leaf value */
	281	#define LITOL2BSZ(n,m,b) ((((n) == 0) ? (m) : cnttz((n))) + (b))
	282
	283	/* convert a block number to a dmap control leaf index */
	284	#define BLKTOCTLLEAF(b,m) \
	285	(((b) & (((s64)1 << ((m) + L2LPERCTL)) - 1)) >> (m))
	286
	287	/* convert log2 leaf value to buddy size */
	288	#define BUDSIZE(s,m) (1 << ((s) - (m)))
	289
	290	/*
	291	* external references.
	292	*/
	293	extern int dbMount(struct inode *ipbmap);
	294
	295	extern int dbUnmount(struct inode *ipbmap, int mounterror);
	296
	297	extern int dbFree(struct inode *ipbmap, s64 blkno, s64 nblocks);
	298
	299	extern int dbUpdatePMap(struct inode *ipbmap,
	300	int free, s64 blkno, s64 nblocks, struct tblock * tblk);
	301
	302	extern int dbNextAG(struct inode *ipbmap);
	303
	304	extern int dbAlloc(struct inode ipbmap, s64 hint, s64 nblocks, s64 results);
	305
	306	extern int dbReAlloc(struct inode *ipbmap,
	307	s64 blkno, s64 nblocks, s64 addnblocks, s64 * results);
	308
	309	extern int dbSync(struct inode *ipbmap);
	310	extern int dbAllocBottomUp(struct inode *ip, s64 blkno, s64 nblocks);
	311	extern int dbExtendFS(struct inode *ipbmap, s64 blkno, s64 nblocks);
	312	extern void dbFinalizeBmap(struct inode *ipbmap);
	313	extern s64 dbMapFileSizeToMapSize(struct inode *ipbmap);
b40c2e66 TR	314	extern s64 dbDiscardAG(struct inode *ip, int agno, s64 minlen);
b40c2e66 TR	315
1da177e4	316	#endif /* _H_JFS_DMAP */