xref: /openbmc/linux/fs/jfs/jfs_imap.h (revision e65e175b)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  *   Copyright (C) International Business Machines Corp., 2000-2002
4  */
5 #ifndef	_H_JFS_IMAP
6 #define _H_JFS_IMAP
7 
8 #include "jfs_txnmgr.h"
9 
10 /*
11  *	jfs_imap.h: disk inode manager
12  */
13 
14 #define	EXTSPERIAG	128	/* number of disk inode extent per iag	*/
15 #define IMAPBLKNO	0	/* lblkno of dinomap within inode map	*/
16 #define SMAPSZ		4	/* number of words per summary map	*/
17 #define	EXTSPERSUM	32	/* number of extents per summary map entry */
18 #define	L2EXTSPERSUM	5	/* l2 number of extents per summary map */
19 #define	PGSPERIEXT	4	/* number of 4K pages per dinode extent */
20 #define	MAXIAGS		((1<<20)-1)	/* maximum number of iags	*/
21 #define	MAXAG		128	/* maximum number of allocation groups	*/
22 
23 #define AMAPSIZE	512	/* bytes in the IAG allocation maps */
24 #define SMAPSIZE	16	/* bytes in the IAG summary maps */
25 
26 /* convert inode number to iag number */
27 #define	INOTOIAG(ino)	((ino) >> L2INOSPERIAG)
28 
29 /* convert iag number to logical block number of the iag page */
30 #define IAGTOLBLK(iagno,l2nbperpg)	(((iagno) + 1) << (l2nbperpg))
31 
32 /* get the starting block number of the 4K page of an inode extent
33  * that contains ino.
34  */
35 #define INOPBLK(pxd,ino,l2nbperpg)	(addressPXD((pxd)) +		\
36 	((((ino) & (INOSPEREXT-1)) >> L2INOSPERPAGE) << (l2nbperpg)))
37 
38 /*
39  *	inode allocation map:
40  *
41  * inode allocation map consists of
42  * . the inode map control page and
43  * . inode allocation group pages (per 4096 inodes)
44  * which are addressed by standard JFS xtree.
45  */
46 /*
47  *	inode allocation group page (per 4096 inodes of an AG)
48  */
49 struct iag {
50 	__le64 agstart;		/* 8: starting block of ag		*/
51 	__le32 iagnum;		/* 4: inode allocation group number	*/
52 	__le32 inofreefwd;	/* 4: ag inode free list forward	*/
53 	__le32 inofreeback;	/* 4: ag inode free list back		*/
54 	__le32 extfreefwd;	/* 4: ag inode extent free list forward	*/
55 	__le32 extfreeback;	/* 4: ag inode extent free list back	*/
56 	__le32 iagfree;		/* 4: iag free list			*/
57 
58 	/* summary map: 1 bit per inode extent */
59 	__le32 inosmap[SMAPSZ];	/* 16: sum map of mapwords w/ free inodes;
60 				 *	note: this indicates free and backed
61 				 *	inodes, if the extent is not backed the
62 				 *	value will be 1.  if the extent is
63 				 *	backed but all inodes are being used the
64 				 *	value will be 1.  if the extent is
65 				 *	backed but at least one of the inodes is
66 				 *	free the value will be 0.
67 				 */
68 	__le32 extsmap[SMAPSZ];	/* 16: sum map of mapwords w/ free extents */
69 	__le32 nfreeinos;	/* 4: number of free inodes		*/
70 	__le32 nfreeexts;	/* 4: number of free extents		*/
71 	/* (72) */
72 	u8 pad[1976];		/* 1976: pad to 2048 bytes */
73 	/* allocation bit map: 1 bit per inode (0 - free, 1 - allocated) */
74 	__le32 wmap[EXTSPERIAG];	/* 512: working allocation map */
75 	__le32 pmap[EXTSPERIAG];	/* 512: persistent allocation map */
76 	pxd_t inoext[EXTSPERIAG];	/* 1024: inode extent addresses */
77 };				/* (4096) */
78 
79 /*
80  *	per AG control information (in inode map control page)
81  */
82 struct iagctl_disk {
83 	__le32 inofree;		/* 4: free inode list anchor		*/
84 	__le32 extfree;		/* 4: free extent list anchor		*/
85 	__le32 numinos;		/* 4: number of backed inodes		*/
86 	__le32 numfree;		/* 4: number of free inodes		*/
87 };				/* (16) */
88 
89 struct iagctl {
90 	int inofree;		/* free inode list anchor		*/
91 	int extfree;		/* free extent list anchor		*/
92 	int numinos;		/* number of backed inodes		*/
93 	int numfree;		/* number of free inodes		*/
94 };
95 
96 /*
97  *	per fileset/aggregate inode map control page
98  */
99 struct dinomap_disk {
100 	__le32 in_freeiag;	/* 4: free iag list anchor	*/
101 	__le32 in_nextiag;	/* 4: next free iag number	*/
102 	__le32 in_numinos;	/* 4: num of backed inodes	*/
103 	__le32 in_numfree;	/* 4: num of free backed inodes */
104 	__le32 in_nbperiext;	/* 4: num of blocks per inode extent */
105 	__le32 in_l2nbperiext;	/* 4: l2 of in_nbperiext	*/
106 	__le32 in_diskblock;	/* 4: for standalone test driver */
107 	__le32 in_maxag;	/* 4: for standalone test driver */
108 	u8 pad[2016];		/* 2016: pad to 2048		*/
109 	struct iagctl_disk in_agctl[MAXAG]; /* 2048: AG control information */
110 };				/* (4096) */
111 
112 struct dinomap {
113 	int in_freeiag;		/* free iag list anchor		*/
114 	int in_nextiag;		/* next free iag number		*/
115 	int in_numinos;		/* num of backed inodes		*/
116 	int in_numfree;		/* num of free backed inodes	*/
117 	int in_nbperiext;	/* num of blocks per inode extent */
118 	int in_l2nbperiext;	/* l2 of in_nbperiext		*/
119 	int in_diskblock;	/* for standalone test driver	*/
120 	int in_maxag;		/* for standalone test driver	*/
121 	struct iagctl in_agctl[MAXAG];	/* AG control information */
122 };
123 
124 /*
125  *	In-core inode map control page
126  */
127 struct inomap {
128 	struct dinomap im_imap;		/* 4096: inode allocation control */
129 	struct inode *im_ipimap;	/* 4: ptr to inode for imap	*/
130 	struct mutex im_freelock;	/* 4: iag free list lock	*/
131 	struct mutex im_aglock[MAXAG];	/* 512: per AG locks		*/
132 	u32 *im_DBGdimap;
133 	atomic_t im_numinos;	/* num of backed inodes */
134 	atomic_t im_numfree;	/* num of free backed inodes */
135 };
136 
137 #define	im_freeiag	im_imap.in_freeiag
138 #define	im_nextiag	im_imap.in_nextiag
139 #define	im_agctl	im_imap.in_agctl
140 #define	im_nbperiext	im_imap.in_nbperiext
141 #define	im_l2nbperiext	im_imap.in_l2nbperiext
142 
143 /* for standalone testdriver
144  */
145 #define	im_diskblock	im_imap.in_diskblock
146 #define	im_maxag	im_imap.in_maxag
147 
148 extern int diFree(struct inode *);
149 extern int diAlloc(struct inode *, bool, struct inode *);
150 extern int diSync(struct inode *);
151 /* external references */
152 extern int diUpdatePMap(struct inode *ipimap, unsigned long inum,
153 			bool is_free, struct tblock * tblk);
154 extern int diExtendFS(struct inode *ipimap, struct inode *ipbmap);
155 extern int diMount(struct inode *);
156 extern int diUnmount(struct inode *, int);
157 extern int diRead(struct inode *);
158 extern struct inode *diReadSpecial(struct super_block *, ino_t, int);
159 extern void diWriteSpecial(struct inode *, int);
160 extern void diFreeSpecial(struct inode *);
161 extern int diWrite(tid_t tid, struct inode *);
162 #endif				/* _H_JFS_IMAP */
163