patch-2.4.20 linux-2.4.20/fs/jfs/jfs_dmap.h

• Lines: 300
• Date: Thu Nov 28 15:53:15 2002
• Orig file: linux-2.4.19/fs/jfs/jfs_dmap.h
• Orig date: Wed Dec 31 16:00:00 1969

diff -urN linux-2.4.19/fs/jfs/jfs_dmap.h linux-2.4.20/fs/jfs/jfs_dmap.h
@@ -0,0 +1,299 @@
+/*
+ *   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 {
+	s32 nleafs;		/* 4: number of tree leafs      */
+	s32 l2nleafs;		/* 4: l2 number of tree leafs   */
+	s32 leafidx;		/* 4: index of first tree leaf  */
+	s32 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 {
+	s32 nblocks;		/* 4: num blks covered by this dmap     */
+	s32 nfree;		/* 4: num of free blks in this dmap     */
+	s64 start;		/* 8: starting blkno for this dmap      */
+	struct dmaptree tree;	/* 360: dmap tree                       */
+	u8 pad[1672];		/* 1672: pad to 2048 bytes              */
+	u32 wmap[LPERDMAP];	/* 1024: bits of the working map        */
+	u32 pmap[LPERDMAP];	/* 1024: bits of the persistent map     */
+};				/* - 4096 -                             */
+
+/*
+ *	disk map control page per level.
+ *
+ * dmapctl must be consistent with dmaptree.
+ */
+struct dmapctl {
+	s32 nleafs;		/* 4: number of tree leafs      */
+	s32 l2nleafs;		/* 4: l2 number of tree leafs   */
+	s32 leafidx;		/* 4: index of the first tree leaf      */
+	s32 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 {
+	s64 dn_mapsize;		/* 8: number of blocks in aggregate     */
+	s64 dn_nfree;		/* 8: num free blks in aggregate map    */
+	s32 dn_l2nbperpage;	/* 4: number of blks per page           */
+	s32 dn_numag;		/* 4: total number of ags               */
+	s32 dn_maxlevel;	/* 4: number of active ags              */
+	s32 dn_maxag;		/* 4: max active alloc group number     */
+	s32 dn_agpref;		/* 4: preferred alloc group (hint)      */
+	s32 dn_aglevel;		/* 4: dmapctl level holding the AG      */
+	s32 dn_agheigth;	/* 4: height in dmapctl of the AG       */
+	s32 dn_agwidth;		/* 4: width in dmapctl of the AG        */
+	s32 dn_agstart;		/* 4: start tree index at AG height     */
+	s32 dn_agl2size;	/* 4: l2 num of blks per alloc group    */
+	s64 dn_agfree[MAXAG];	/* 8*MAXAG: per AG free count           */
+	s64 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 -                             */
+
+/* 
+ *	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 semaphore 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_agheigth	db_bmap.dn_agheigth
+#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 dbAllocExact(struct inode *ip, s64 blkno, int nblocks);
+
+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 */