- 根目录:
- 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);
#endif /* _H_JFS_DMAP */