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

• Lines: 158
• Date: Thu Nov 28 15:53:15 2002
• Orig file: linux-2.4.19/fs/jfs/jfs_imap.h
• Orig date: Wed Dec 31 16:00:00 1969

diff -urN linux-2.4.19/fs/jfs/jfs_imap.h linux-2.4.20/fs/jfs/jfs_imap.h
@@ -0,0 +1,157 @@
+/*
+ *   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_IMAP
+#define _H_JFS_IMAP
+
+#include "jfs_txnmgr.h"
+
+/*
+ *	jfs_imap.h: disk inode manager
+ */
+
+#define	EXTSPERIAG	128	/* number of disk inode extent per iag  */
+#define IMAPBLKNO	0	/* lblkno of dinomap within inode map   */
+#define SMAPSZ		4	/* number of words per summary map      */
+#define	EXTSPERSUM	32	/* number of extents per summary map entry */
+#define	L2EXTSPERSUM	5	/* l2 number of extents per summary map */
+#define	PGSPERIEXT	4	/* number of 4K pages per dinode extent */
+#define	MAXIAGS		((1<<20)-1)	/* maximum number of iags       */
+#define	MAXAG		128	/* maximum number of allocation groups  */
+
+#define AMAPSIZE      512	/* bytes in the IAG allocation maps */
+#define SMAPSIZE      16	/* bytes in the IAG summary maps */
+
+/* convert inode number to iag number */
+#define	INOTOIAG(ino)	((ino) >> L2INOSPERIAG)
+
+/* convert iag number to logical block number of the iag page */
+#define IAGTOLBLK(iagno,l2nbperpg)	(((iagno) + 1) << (l2nbperpg))
+
+/* get the starting block number of the 4K page of an inode extent
+ * that contains ino.
+ */
+#define INOPBLK(pxd,ino,l2nbperpg)    	(addressPXD((pxd)) +		\
+	((((ino) & (INOSPEREXT-1)) >> L2INOSPERPAGE) << (l2nbperpg)))
+
+/*
+ *	inode allocation map:
+ * 
+ * inode allocation map consists of 
+ * . the inode map control page and
+ * . inode allocation group pages (per 4096 inodes)
+ * which are addressed by standard JFS xtree.
+ */
+/*
+ *	inode allocation group page (per 4096 inodes of an AG)
+ */
+struct iag {
+	s64 agstart;		/* 8: starting block of ag              */
+	s32 iagnum;		/* 4: inode allocation group number     */
+	s32 inofreefwd;		/* 4: ag inode free list forward        */
+	s32 inofreeback;	/* 4: ag inode free list back           */
+	s32 extfreefwd;		/* 4: ag inode extent free list forward */
+	s32 extfreeback;	/* 4: ag inode extent free list back    */
+	s32 iagfree;		/* 4: iag free list                     */
+
+	/* summary map: 1 bit per inode extent */
+	s32 inosmap[SMAPSZ];	/* 16: sum map of mapwords w/ free inodes;
+				 *      note: this indicates free and backed
+				 *      inodes, if the extent is not backed the
+				 *      value will be 1.  if the extent is
+				 *      backed but all inodes are being used the
+				 *      value will be 1.  if the extent is
+				 *      backed but at least one of the inodes is
+				 *      free the value will be 0.
+				 */
+	s32 extsmap[SMAPSZ];	/* 16: sum map of mapwords w/ free extents */
+	s32 nfreeinos;		/* 4: number of free inodes             */
+	s32 nfreeexts;		/* 4: number of free extents            */
+	/* (72) */
+	u8 pad[1976];		/* 1976: pad to 2048 bytes */
+	/* allocation bit map: 1 bit per inode (0 - free, 1 - allocated) */
+	u32 wmap[EXTSPERIAG];	/* 512: working allocation map  */
+	u32 pmap[EXTSPERIAG];	/* 512: persistent allocation map */
+	pxd_t inoext[EXTSPERIAG];	/* 1024: inode extent addresses */
+};				/* (4096) */
+
+/*
+ *	per AG control information (in inode map control page)
+ */
+struct iagctl {
+	s32 inofree;		/* 4: free inode list anchor            */
+	s32 extfree;		/* 4: free extent list anchor           */
+	s32 numinos;		/* 4: number of backed inodes           */
+	s32 numfree;		/* 4: number of free inodes             */
+};				/* (16) */
+
+/*
+ *	per fileset/aggregate inode map control page
+ */
+struct dinomap {
+	s32 in_freeiag;		/* 4: free iag list anchor     */
+	s32 in_nextiag;		/* 4: next free iag number     */
+	s32 in_numinos;		/* 4: num of backed inodes */
+	s32 in_numfree;		/* 4: num of free backed inodes */
+	s32 in_nbperiext;	/* 4: num of blocks per inode extent */
+	s32 in_l2nbperiext;	/* 4: l2 of in_nbperiext */
+	s32 in_diskblock;	/* 4: for standalone test driver  */
+	s32 in_maxag;		/* 4: for standalone test driver  */
+	u8 pad[2016];		/* 2016: pad to 2048 */
+	struct iagctl in_agctl[MAXAG];	/* 2048: AG control information */
+};				/* (4096) */
+
+
+/*
+ *	In-core inode map control page
+ */
+struct inomap {
+	struct dinomap im_imap;		/* 4096: inode allocation control */
+	struct inode *im_ipimap;	/* 4: ptr to inode for imap   */
+	struct semaphore im_freelock;	/* 4: iag free list lock      */
+	struct semaphore im_aglock[MAXAG];	/* 512: per AG locks          */
+	u32 *im_DBGdimap;
+	atomic_t im_numinos;	/* num of backed inodes */
+	atomic_t im_numfree;	/* num of free backed inodes */
+};
+
+#define	im_freeiag	im_imap.in_freeiag
+#define	im_nextiag	im_imap.in_nextiag
+#define	im_agctl	im_imap.in_agctl
+#define	im_nbperiext	im_imap.in_nbperiext
+#define	im_l2nbperiext	im_imap.in_l2nbperiext
+
+/* for standalone testdriver
+ */
+#define	im_diskblock	im_imap.in_diskblock
+#define	im_maxag	im_imap.in_maxag
+
+extern int diFree(struct inode *);
+extern int diAlloc(struct inode *, boolean_t, struct inode *);
+extern int diSync(struct inode *);
+/* external references */
+extern int diUpdatePMap(struct inode *ipimap, unsigned long inum,
+			boolean_t is_free, struct tblock * tblk);
+extern int diExtendFS(struct inode *ipimap, struct inode *ipbmap);
+extern int diMount(struct inode *);
+extern int diUnmount(struct inode *, int);
+extern int diRead(struct inode *);
+extern struct inode *diReadSpecial(struct super_block *, ino_t, int);
+extern void diWriteSpecial(struct inode *, int);
+extern void diFreeSpecial(struct inode *);
+extern int diWrite(tid_t tid, struct inode *);
+#endif				/* _H_JFS_IMAP */