1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
|
#ifndef _SYSV_H
#define _SYSV_H
#include <linux/buffer_head.h>
typedef __u16 __bitwise __fs16;
typedef __u32 __bitwise __fs32;
#include <linux/sysv_fs.h>
/*
* SystemV/V7/Coherent super-block data in memory
*
* The SystemV/V7/Coherent superblock contains dynamic data (it gets modified
* while the system is running). This is in contrast to the Minix and Berkeley
* filesystems (where the superblock is never modified). This affects the
* sync() operation: we must keep the superblock in a disk buffer and use this
* one as our "working copy".
*/
struct sysv_sb_info {
struct super_block *s_sb; /* VFS superblock */
int s_type; /* file system type: FSTYPE_{XENIX|SYSV|COH} */
char s_bytesex; /* bytesex (le/be/pdp) */
char s_truncate; /* if 1: names > SYSV_NAMELEN chars are truncated */
/* if 0: they are disallowed (ENAMETOOLONG) */
nlink_t s_link_max; /* max number of hard links to a file */
unsigned int s_inodes_per_block; /* number of inodes per block */
unsigned int s_inodes_per_block_1; /* inodes_per_block - 1 */
unsigned int s_inodes_per_block_bits; /* log2(inodes_per_block) */
unsigned int s_ind_per_block; /* number of indirections per block */
unsigned int s_ind_per_block_bits; /* log2(ind_per_block) */
unsigned int s_ind_per_block_2; /* ind_per_block ^ 2 */
unsigned int s_toobig_block; /* 10 + ipb + ipb^2 + ipb^3 */
unsigned int s_block_base; /* physical block number of block 0 */
unsigned short s_fic_size; /* free inode cache size, NICINOD */
unsigned short s_flc_size; /* free block list chunk size, NICFREE */
/* The superblock is kept in one or two disk buffers: */
struct buffer_head *s_bh1;
struct buffer_head *s_bh2;
/* These are pointers into the disk buffer, to compensate for
different superblock layout. */
char * s_sbd1; /* entire superblock data, for part 1 */
char * s_sbd2; /* entire superblock data, for part 2 */
__fs16 *s_sb_fic_count; /* pointer to s_sbd->s_ninode */
sysv_ino_t *s_sb_fic_inodes; /* pointer to s_sbd->s_inode */
__fs16 *s_sb_total_free_inodes; /* pointer to s_sbd->s_tinode */
__fs16 *s_bcache_count; /* pointer to s_sbd->s_nfree */
sysv_zone_t *s_bcache; /* pointer to s_sbd->s_free */
__fs32 *s_free_blocks; /* pointer to s_sbd->s_tfree */
__fs32 *s_sb_time; /* pointer to s_sbd->s_time */
__fs32 *s_sb_state; /* pointer to s_sbd->s_state, only FSTYPE_SYSV */
/* We keep those superblock entities that don't change here;
this saves us an indirection and perhaps a conversion. */
u32 s_firstinodezone; /* index of first inode zone */
u32 s_firstdatazone; /* same as s_sbd->s_isize */
u32 s_ninodes; /* total number of inodes */
u32 s_ndatazones; /* total number of data zones */
u32 s_nzones; /* same as s_sbd->s_fsize */
u16 s_namelen; /* max length of dir entry */
int s_forced_ro;
};
/*
* SystemV/V7/Coherent FS inode data in memory
*/
struct sysv_inode_info {
__fs32 i_data[13];
u32 i_dir_start_lookup;
struct inode vfs_inode;
};
static inline struct sysv_inode_info *SYSV_I(struct inode *inode)
{
return list_entry(inode, struct sysv_inode_info, vfs_inode);
}
static inline struct sysv_sb_info *SYSV_SB(struct super_block *sb)
{
return sb->s_fs_info;
}
/* identify the FS in memory */
enum {
FSTYPE_NONE = 0,
FSTYPE_XENIX,
FSTYPE_SYSV4,
FSTYPE_SYSV2,
FSTYPE_COH,
FSTYPE_V7,
FSTYPE_AFS,
FSTYPE_END,
};
#define SYSV_MAGIC_BASE 0x012FF7B3
#define XENIX_SUPER_MAGIC (SYSV_MAGIC_BASE+FSTYPE_XENIX)
#define SYSV4_SUPER_MAGIC (SYSV_MAGIC_BASE+FSTYPE_SYSV4)
#define SYSV2_SUPER_MAGIC (SYSV_MAGIC_BASE+FSTYPE_SYSV2)
#define COH_SUPER_MAGIC (SYSV_MAGIC_BASE+FSTYPE_COH)
/* Admissible values for i_nlink: 0.._LINK_MAX */
enum {
XENIX_LINK_MAX = 126, /* ?? */
SYSV_LINK_MAX = 126, /* 127? 251? */
V7_LINK_MAX = 126, /* ?? */
COH_LINK_MAX = 10000,
};
static inline void dirty_sb(struct super_block *sb)
{
struct sysv_sb_info *sbi = SYSV_SB(sb);
mark_buffer_dirty(sbi->s_bh1);
if (sbi->s_bh1 != sbi->s_bh2)
mark_buffer_dirty(sbi->s_bh2);
sb->s_dirt = 1;
}
/* ialloc.c */
extern struct sysv_inode *sysv_raw_inode(struct super_block *, unsigned,
struct buffer_head **);
extern struct inode * sysv_new_inode(const struct inode *, mode_t);
extern void sysv_free_inode(struct inode *);
extern unsigned long sysv_count_free_inodes(struct super_block *);
/* balloc.c */
extern sysv_zone_t sysv_new_block(struct super_block *);
extern void sysv_free_block(struct super_block *, sysv_zone_t);
extern unsigned long sysv_count_free_blocks(struct super_block *);
/* itree.c */
extern void sysv_truncate(struct inode *);
extern int __sysv_write_begin(struct file *file, struct address_space *mapping,
loff_t pos, unsigned len, unsigned flags,
struct page **pagep, void **fsdata);
/* inode.c */
extern struct inode *sysv_iget(struct super_block *, unsigned int);
extern int sysv_write_inode(struct inode *, struct writeback_control *wbc);
extern int sysv_sync_inode(struct inode *);
extern void sysv_set_inode(struct inode *, dev_t);
extern int sysv_getattr(struct vfsmount *, struct dentry *, struct kstat *);
extern int sysv_init_icache(void);
extern void sysv_destroy_icache(void);
/* dir.c */
extern struct sysv_dir_entry *sysv_find_entry(struct dentry *, struct page **);
extern int sysv_add_link(struct dentry *, struct inode *);
extern int sysv_delete_entry(struct sysv_dir_entry *, struct page *);
extern int sysv_make_empty(struct inode *, struct inode *);
extern int sysv_empty_dir(struct inode *);
extern void sysv_set_link(struct sysv_dir_entry *, struct page *,
struct inode *);
extern struct sysv_dir_entry *sysv_dotdot(struct inode *, struct page **);
extern ino_t sysv_inode_by_name(struct dentry *);
extern const struct inode_operations sysv_file_inode_operations;
extern const struct inode_operations sysv_dir_inode_operations;
extern const struct inode_operations sysv_fast_symlink_inode_operations;
extern const struct file_operations sysv_file_operations;
extern const struct file_operations sysv_dir_operations;
extern const struct address_space_operations sysv_aops;
extern const struct super_operations sysv_sops;
extern const struct dentry_operations sysv_dentry_operations;
enum {
BYTESEX_LE,
BYTESEX_PDP,
BYTESEX_BE,
};
static inline u32 PDP_swab(u32 x)
{
#ifdef __LITTLE_ENDIAN
return ((x & 0xffff) << 16) | ((x & 0xffff0000) >> 16);
#else
#ifdef __BIG_ENDIAN
return ((x & 0xff00ff) << 8) | ((x & 0xff00ff00) >> 8);
#else
#error BYTESEX
#endif
#endif
}
static inline __u32 fs32_to_cpu(struct sysv_sb_info *sbi, __fs32 n)
{
if (sbi->s_bytesex == BYTESEX_PDP)
return PDP_swab((__force __u32)n);
else if (sbi->s_bytesex == BYTESEX_LE)
return le32_to_cpu((__force __le32)n);
else
return be32_to_cpu((__force __be32)n);
}
static inline __fs32 cpu_to_fs32(struct sysv_sb_info *sbi, __u32 n)
{
if (sbi->s_bytesex == BYTESEX_PDP)
return (__force __fs32)PDP_swab(n);
else if (sbi->s_bytesex == BYTESEX_LE)
return (__force __fs32)cpu_to_le32(n);
else
return (__force __fs32)cpu_to_be32(n);
}
static inline __fs32 fs32_add(struct sysv_sb_info *sbi, __fs32 *n, int d)
{
if (sbi->s_bytesex == BYTESEX_PDP)
*(__u32*)n = PDP_swab(PDP_swab(*(__u32*)n)+d);
else if (sbi->s_bytesex == BYTESEX_LE)
le32_add_cpu((__le32 *)n, d);
else
be32_add_cpu((__be32 *)n, d);
return *n;
}
static inline __u16 fs16_to_cpu(struct sysv_sb_info *sbi, __fs16 n)
{
if (sbi->s_bytesex != BYTESEX_BE)
return le16_to_cpu((__force __le16)n);
else
return be16_to_cpu((__force __be16)n);
}
static inline __fs16 cpu_to_fs16(struct sysv_sb_info *sbi, __u16 n)
{
if (sbi->s_bytesex != BYTESEX_BE)
return (__force __fs16)cpu_to_le16(n);
else
return (__force __fs16)cpu_to_be16(n);
}
static inline __fs16 fs16_add(struct sysv_sb_info *sbi, __fs16 *n, int d)
{
if (sbi->s_bytesex != BYTESEX_BE)
le16_add_cpu((__le16 *)n, d);
else
be16_add_cpu((__be16 *)n, d);
return *n;
}
#endif /* _SYSV_H */
|
