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 */
49struct 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 */
82struct 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
89struct 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 */
99struct 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
112struct 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 */
127struct 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
148extern int diFree(struct inode *);
149extern int diAlloc(struct inode *, bool, struct inode *);
150extern int diSync(struct inode *);
151/* external references */
152extern int diUpdatePMap(struct inode *ipimap, unsigned long inum,
153 bool is_free, struct tblock * tblk);
154extern int diExtendFS(struct inode *ipimap, struct inode *ipbmap);
155extern int diMount(struct inode *);
156extern int diUnmount(struct inode *, int);
157extern int diRead(struct inode *);
158extern struct inode *diReadSpecial(struct super_block *, ino_t, int);
159extern void diWriteSpecial(struct inode *, int);
160extern void diFreeSpecial(struct inode *);
161extern int diWrite(tid_t tid, struct inode *);
162#endif /* _H_JFS_IMAP */
163

source code of linux/fs/jfs/jfs_imap.h