xref: /linux/fs/jfs/jfs_imap.h (revision 96de0e252cedffad61b3cb5e05662c591898e69a)
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 	__le64 agstart;		/* 8: starting block of ag		*/
64 	__le32 iagnum;		/* 4: inode allocation group number	*/
65 	__le32 inofreefwd;	/* 4: ag inode free list forward	*/
66 	__le32 inofreeback;	/* 4: ag inode free list back		*/
67 	__le32 extfreefwd;	/* 4: ag inode extent free list forward	*/
68 	__le32 extfreeback;	/* 4: ag inode extent free list back	*/
69 	__le32 iagfree;		/* 4: iag free list			*/
70 
71 	/* summary map: 1 bit per inode extent */
72 	__le32 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 	__le32 extsmap[SMAPSZ];	/* 16: sum map of mapwords w/ free extents */
82 	__le32 nfreeinos;	/* 4: number of free inodes		*/
83 	__le32 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 	__le32 wmap[EXTSPERIAG];	/* 512: working allocation map */
88 	__le32 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_disk {
96 	__le32 inofree;		/* 4: free inode list anchor		*/
97 	__le32 extfree;		/* 4: free extent list anchor		*/
98 	__le32 numinos;		/* 4: number of backed inodes		*/
99 	__le32 numfree;		/* 4: number of free inodes		*/
100 };				/* (16) */
101 
102 struct iagctl {
103 	int inofree;		/* free inode list anchor		*/
104 	int extfree;		/* free extent list anchor		*/
105 	int numinos;		/* number of backed inodes		*/
106 	int numfree;		/* number of free inodes		*/
107 };
108 
109 /*
110  *	per fileset/aggregate inode map control page
111  */
112 struct dinomap_disk {
113 	__le32 in_freeiag;	/* 4: free iag list anchor	*/
114 	__le32 in_nextiag;	/* 4: next free iag number	*/
115 	__le32 in_numinos;	/* 4: num of backed inodes	*/
116 	__le32 in_numfree;	/* 4: num of free backed inodes */
117 	__le32 in_nbperiext;	/* 4: num of blocks per inode extent */
118 	__le32 in_l2nbperiext;	/* 4: l2 of in_nbperiext	*/
119 	__le32 in_diskblock;	/* 4: for standalone test driver */
120 	__le32 in_maxag;	/* 4: for standalone test driver */
121 	u8 pad[2016];		/* 2016: pad to 2048		*/
122 	struct iagctl_disk in_agctl[MAXAG]; /* 2048: AG control information */
123 };				/* (4096) */
124 
125 struct dinomap {
126 	int in_freeiag;		/* free iag list anchor		*/
127 	int in_nextiag;		/* next free iag number		*/
128 	int in_numinos;		/* num of backed inodes		*/
129 	int in_numfree;		/* num of free backed inodes	*/
130 	int in_nbperiext;	/* num of blocks per inode extent */
131 	int in_l2nbperiext;	/* l2 of in_nbperiext		*/
132 	int in_diskblock;	/* for standalone test driver	*/
133 	int in_maxag;		/* for standalone test driver	*/
134 	struct iagctl in_agctl[MAXAG];	/* AG control information */
135 };
136 
137 /*
138  *	In-core inode map control page
139  */
140 struct inomap {
141 	struct dinomap im_imap;		/* 4096: inode allocation control */
142 	struct inode *im_ipimap;	/* 4: ptr to inode for imap	*/
143 	struct mutex im_freelock;	/* 4: iag free list lock	*/
144 	struct mutex im_aglock[MAXAG];	/* 512: per AG locks		*/
145 	u32 *im_DBGdimap;
146 	atomic_t im_numinos;	/* num of backed inodes */
147 	atomic_t im_numfree;	/* num of free backed inodes */
148 };
149 
150 #define	im_freeiag	im_imap.in_freeiag
151 #define	im_nextiag	im_imap.in_nextiag
152 #define	im_agctl	im_imap.in_agctl
153 #define	im_nbperiext	im_imap.in_nbperiext
154 #define	im_l2nbperiext	im_imap.in_l2nbperiext
155 
156 /* for standalone testdriver
157  */
158 #define	im_diskblock	im_imap.in_diskblock
159 #define	im_maxag	im_imap.in_maxag
160 
161 extern int diFree(struct inode *);
162 extern int diAlloc(struct inode *, bool, struct inode *);
163 extern int diSync(struct inode *);
164 /* external references */
165 extern int diUpdatePMap(struct inode *ipimap, unsigned long inum,
166 			bool is_free, struct tblock * tblk);
167 extern int diExtendFS(struct inode *ipimap, struct inode *ipbmap);
168 extern int diMount(struct inode *);
169 extern int diUnmount(struct inode *, int);
170 extern int diRead(struct inode *);
171 extern struct inode *diReadSpecial(struct super_block *, ino_t, int);
172 extern void diWriteSpecial(struct inode *, int);
173 extern void diFreeSpecial(struct inode *);
174 extern int diWrite(tid_t tid, struct inode *);
175 #endif				/* _H_JFS_IMAP */
176