1/* SPDX-License-Identifier: GPL-2.0-or-later */
2/*
3 * Copyright (C) International Business Machines Corp., 2000-2003
4 */
5#ifndef _H_JFS_SUPERBLOCK
6#define _H_JFS_SUPERBLOCK
7
8#include <linux/uuid.h>
9
10/*
11 * make the magic number something a human could read
12 */
13#define JFS_MAGIC "JFS1" /* Magic word */
14
15#define JFS_VERSION 2 /* Version number: Version 2 */
16
17#define LV_NAME_SIZE 11 /* MUST BE 11 for OS/2 boot sector */
18
19/*
20 * aggregate superblock
21 *
22 * The name superblock is too close to super_block, so the name has been
23 * changed to jfs_superblock. The utilities are still using the old name.
24 */
25struct jfs_superblock {
26 char s_magic[4]; /* 4: magic number */
27 __le32 s_version; /* 4: version number */
28
29 __le64 s_size; /* 8: aggregate size in hardware/LVM blocks;
30 * VFS: number of blocks
31 */
32 __le32 s_bsize; /* 4: aggregate block size in bytes;
33 * VFS: fragment size
34 */
35 __le16 s_l2bsize; /* 2: log2 of s_bsize */
36 __le16 s_l2bfactor; /* 2: log2(s_bsize/hardware block size) */
37 __le32 s_pbsize; /* 4: hardware/LVM block size in bytes */
38 __le16 s_l2pbsize; /* 2: log2 of s_pbsize */
39 __le16 pad; /* 2: padding necessary for alignment */
40
41 __le32 s_agsize; /* 4: allocation group size in aggr. blocks */
42
43 __le32 s_flag; /* 4: aggregate attributes:
44 * see jfs_filsys.h
45 */
46 __le32 s_state; /* 4: mount/unmount/recovery state:
47 * see jfs_filsys.h
48 */
49 __le32 s_compress; /* 4: > 0 if data compression */
50
51 pxd_t s_ait2; /* 8: first extent of secondary
52 * aggregate inode table
53 */
54
55 pxd_t s_aim2; /* 8: first extent of secondary
56 * aggregate inode map
57 */
58 __le32 s_logdev; /* 4: device address of log */
59 __le32 s_logserial; /* 4: log serial number at aggregate mount */
60 pxd_t s_logpxd; /* 8: inline log extent */
61
62 pxd_t s_fsckpxd; /* 8: inline fsck work space extent */
63
64 struct timestruc_t s_time; /* 8: time last updated */
65
66 __le32 s_fsckloglen; /* 4: Number of filesystem blocks reserved for
67 * the fsck service log.
68 * N.B. These blocks are divided among the
69 * versions kept. This is not a per
70 * version size.
71 * N.B. These blocks are included in the
72 * length field of s_fsckpxd.
73 */
74 s8 s_fscklog; /* 1: which fsck service log is most recent
75 * 0 => no service log data yet
76 * 1 => the first one
77 * 2 => the 2nd one
78 */
79 char s_fpack[11]; /* 11: file system volume name
80 * N.B. This must be 11 bytes to
81 * conform with the OS/2 BootSector
82 * requirements
83 * Only used when s_version is 1
84 */
85
86 /* extendfs() parameter under s_state & FM_EXTENDFS */
87 __le64 s_xsize; /* 8: extendfs s_size */
88 pxd_t s_xfsckpxd; /* 8: extendfs fsckpxd */
89 pxd_t s_xlogpxd; /* 8: extendfs logpxd */
90 uuid_t s_uuid; /* 16: 128-bit uuid for volume */
91 char s_label[16]; /* 16: volume label */
92 uuid_t s_loguuid; /* 16: 128-bit uuid for log device */
93
94};
95
96extern int readSuper(struct super_block *, struct buffer_head **);
97extern int updateSuper(struct super_block *, uint);
98__printf(2, 3)
99extern void jfs_error(struct super_block *, const char *, ...);
100extern int jfs_mount(struct super_block *);
101extern int jfs_mount_rw(struct super_block *, int);
102extern int jfs_umount(struct super_block *);
103extern int jfs_umount_rw(struct super_block *);
104extern int jfs_extendfs(struct super_block *, s64, int);
105
106extern struct task_struct *jfsIOthread;
107extern struct task_struct *jfsSyncThread;
108
109#endif /*_H_JFS_SUPERBLOCK */
110

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