1 /*
2  *   Copyright (c) International Business Machines Corp., 2000-2002
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
6  *   the Free Software Foundation; either version 2 of the License, or
7  *   (at your option) any later version.
8  *
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
15  *   along with this program;  if not, write to the Free Software
16  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
17  */
18 #ifndef	_H_JFS_IMAP
19 #define _H_JFS_IMAP
20 
21 #include "jfs_txnmgr.h"
22 
23 /*
24  *	jfs_imap.h: disk inode manager
25  */
26 
27 #define	EXTSPERIAG	128	/* number of disk inode extent per iag  */
28 #define IMAPBLKNO	0	/* lblkno of dinomap within inode map   */
29 #define SMAPSZ		4	/* number of words per summary map      */
30 #define	EXTSPERSUM	32	/* number of extents per summary map entry */
31 #define	L2EXTSPERSUM	5	/* l2 number of extents per summary map */
32 #define	PGSPERIEXT	4	/* number of 4K pages per dinode extent */
33 #define	MAXIAGS		((1<<20)-1)	/* maximum number of iags       */
34 #define	MAXAG		128	/* maximum number of allocation groups  */
35 
36 #define AMAPSIZE      512	/* bytes in the IAG allocation maps */
37 #define SMAPSIZE      16	/* bytes in the IAG summary maps */
38 
39 /* convert inode number to iag number */
40 #define	INOTOIAG(ino)	((ino) >> L2INOSPERIAG)
41 
42 /* convert iag number to logical block number of the iag page */
43 #define IAGTOLBLK(iagno,l2nbperpg)	(((iagno) + 1) << (l2nbperpg))
44 
45 /* get the starting block number of the 4K page of an inode extent
46  * that contains ino.
47  */
48 #define INOPBLK(pxd,ino,l2nbperpg)    	(addressPXD((pxd)) +		\
49 	((((ino) & (INOSPEREXT-1)) >> L2INOSPERPAGE) << (l2nbperpg)))
50 
51 /*
52  *	inode allocation map:
53  *
54  * inode allocation map consists of
55  * . the inode map control page and
56  * . inode allocation group pages (per 4096 inodes)
57  * which are addressed by standard JFS xtree.
58  */
59 /*
60  *	inode allocation group page (per 4096 inodes of an AG)
61  */
62 struct iag {
63 	s64 agstart;		/* 8: starting block of ag              */
64 	s32 iagnum;		/* 4: inode allocation group number     */
65 	s32 inofreefwd;		/* 4: ag inode free list forward        */
66 	s32 inofreeback;	/* 4: ag inode free list back           */
67 	s32 extfreefwd;		/* 4: ag inode extent free list forward */
68 	s32 extfreeback;	/* 4: ag inode extent free list back    */
69 	s32 iagfree;		/* 4: iag free list                     */
70 
71 	/* summary map: 1 bit per inode extent */
72 	s32 inosmap[SMAPSZ];	/* 16: sum map of mapwords w/ free inodes;
73 				 *      note: this indicates free and backed
74 				 *      inodes, if the extent is not backed the
75 				 *      value will be 1.  if the extent is
76 				 *      backed but all inodes are being used the
77 				 *      value will be 1.  if the extent is
78 				 *      backed but at least one of the inodes is
79 				 *      free the value will be 0.
80 				 */
81 	s32 extsmap[SMAPSZ];	/* 16: sum map of mapwords w/ free extents */
82 	s32 nfreeinos;		/* 4: number of free inodes             */
83 	s32 nfreeexts;		/* 4: number of free extents            */
84 	/* (72) */
85 	u8 pad[1976];		/* 1976: pad to 2048 bytes */
86 	/* allocation bit map: 1 bit per inode (0 - free, 1 - allocated) */
87 	u32 wmap[EXTSPERIAG];	/* 512: working allocation map  */
88 	u32 pmap[EXTSPERIAG];	/* 512: persistent allocation map */
89 	pxd_t inoext[EXTSPERIAG];	/* 1024: inode extent addresses */
90 };				/* (4096) */
91 
92 /*
93  *	per AG control information (in inode map control page)
94  */
95 struct iagctl {
96 	s32 inofree;		/* 4: free inode list anchor            */
97 	s32 extfree;		/* 4: free extent list anchor           */
98 	s32 numinos;		/* 4: number of backed inodes           */
99 	s32 numfree;		/* 4: number of free inodes             */
100 };				/* (16) */
101 
102 /*
103  *	per fileset/aggregate inode map control page
104  */
105 struct dinomap {
106 	s32 in_freeiag;		/* 4: free iag list anchor     */
107 	s32 in_nextiag;		/* 4: next free iag number     */
108 	s32 in_numinos;		/* 4: num of backed inodes */
109 	s32 in_numfree;		/* 4: num of free backed inodes */
110 	s32 in_nbperiext;	/* 4: num of blocks per inode extent */
111 	s32 in_l2nbperiext;	/* 4: l2 of in_nbperiext */
112 	s32 in_diskblock;	/* 4: for standalone test driver  */
113 	s32 in_maxag;		/* 4: for standalone test driver  */
114 	u8 pad[2016];		/* 2016: pad to 2048 */
115 	struct iagctl in_agctl[MAXAG];	/* 2048: AG control information */
116 };				/* (4096) */
117 
118 
119 /*
120  *	In-core inode map control page
121  */
122 struct inomap {
123 	struct dinomap im_imap;		/* 4096: inode allocation control */
124 	struct inode *im_ipimap;	/* 4: ptr to inode for imap   */
125 	struct semaphore im_freelock;	/* 4: iag free list lock      */
126 	struct semaphore im_aglock[MAXAG];	/* 512: per AG locks          */
127 	u32 *im_DBGdimap;
128 	atomic_t im_numinos;	/* num of backed inodes */
129 	atomic_t im_numfree;	/* num of free backed inodes */
130 };
131 
132 #define	im_freeiag	im_imap.in_freeiag
133 #define	im_nextiag	im_imap.in_nextiag
134 #define	im_agctl	im_imap.in_agctl
135 #define	im_nbperiext	im_imap.in_nbperiext
136 #define	im_l2nbperiext	im_imap.in_l2nbperiext
137 
138 /* for standalone testdriver
139  */
140 #define	im_diskblock	im_imap.in_diskblock
141 #define	im_maxag	im_imap.in_maxag
142 
143 extern int diFree(struct inode *);
144 extern int diAlloc(struct inode *, boolean_t, struct inode *);
145 extern int diSync(struct inode *);
146 /* external references */
147 extern int diUpdatePMap(struct inode *ipimap, unsigned long inum,
148 			boolean_t is_free, struct tblock * tblk);
149 extern int diExtendFS(struct inode *ipimap, struct inode *ipbmap);
150 extern int diMount(struct inode *);
151 extern int diUnmount(struct inode *, int);
152 extern int diRead(struct inode *);
153 extern struct inode *diReadSpecial(struct super_block *, ino_t, int);
154 extern void diWriteSpecial(struct inode *, int);
155 extern void diFreeSpecial(struct inode *);
156 extern int diWrite(tid_t tid, struct inode *);
157 #endif				/* _H_JFS_IMAP */
158