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
|
/*
* linux/fs/adfs/dir_fplus.c
*
* Copyright (C) 1997-1999 Russell King
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/buffer_head.h>
#include "adfs.h"
#include "dir_fplus.h"
static int
adfs_fplus_read(struct super_block *sb, unsigned int id, unsigned int sz, struct adfs_dir *dir)
{
struct adfs_bigdirheader *h;
struct adfs_bigdirtail *t;
unsigned long block;
unsigned int blk, size;
int i, ret = -EIO;
dir->nr_buffers = 0;
block = __adfs_block_map(sb, id, 0);
if (!block) {
adfs_error(sb, "dir object %X has a hole at offset 0", id);
goto out;
}
dir->bh[0] = sb_bread(sb, block);
if (!dir->bh[0])
goto out;
dir->nr_buffers += 1;
h = (struct adfs_bigdirheader *)dir->bh[0]->b_data;
size = le32_to_cpu(h->bigdirsize);
if (size != sz) {
printk(KERN_WARNING "adfs: adfs_fplus_read: directory header size\n"
" does not match directory size\n");
}
if (h->bigdirversion[0] != 0 || h->bigdirversion[1] != 0 ||
h->bigdirversion[2] != 0 || size & 2047 ||
h->bigdirstartname != cpu_to_le32(BIGDIRSTARTNAME))
goto out;
size >>= sb->s_blocksize_bits;
for (blk = 1; blk < size; blk++) {
block = __adfs_block_map(sb, id, blk);
if (!block) {
adfs_error(sb, "dir object %X has a hole at offset %d", id, blk);
goto out;
}
dir->bh[blk] = sb_bread(sb, block);
if (!dir->bh[blk])
goto out;
dir->nr_buffers = blk;
}
t = (struct adfs_bigdirtail *)(dir->bh[size - 1]->b_data + (sb->s_blocksize - 8));
if (t->bigdirendname != cpu_to_le32(BIGDIRENDNAME) ||
t->bigdirendmasseq != h->startmasseq ||
t->reserved[0] != 0 || t->reserved[1] != 0)
goto out;
dir->parent_id = le32_to_cpu(h->bigdirparent);
dir->sb = sb;
return 0;
out:
for (i = 0; i < dir->nr_buffers; i++)
brelse(dir->bh[i]);
dir->sb = NULL;
return ret;
}
static int
adfs_fplus_setpos(struct adfs_dir *dir, unsigned int fpos)
{
struct adfs_bigdirheader *h = (struct adfs_bigdirheader *)dir->bh[0]->b_data;
int ret = -ENOENT;
if (fpos <= le32_to_cpu(h->bigdirentries)) {
dir->pos = fpos;
ret = 0;
}
return ret;
}
static void
dir_memcpy(struct adfs_dir *dir, unsigned int offset, void *to, int len)
{
struct super_block *sb = dir->sb;
unsigned int buffer, partial, remainder;
buffer = offset >> sb->s_blocksize_bits;
offset &= sb->s_blocksize - 1;
partial = sb->s_blocksize - offset;
if (partial >= len)
memcpy(to, dir->bh[buffer]->b_data + offset, len);
else {
char *c = (char *)to;
remainder = len - partial;
memcpy(c, dir->bh[buffer]->b_data + offset, partial);
memcpy(c + partial, dir->bh[buffer + 1]->b_data, remainder);
}
}
static int
adfs_fplus_getnext(struct adfs_dir *dir, struct object_info *obj)
{
struct adfs_bigdirheader *h = (struct adfs_bigdirheader *)dir->bh[0]->b_data;
struct adfs_bigdirentry bde;
unsigned int offset;
int i, ret = -ENOENT;
if (dir->pos >= le32_to_cpu(h->bigdirentries))
goto out;
offset = offsetof(struct adfs_bigdirheader, bigdirname);
offset += ((le32_to_cpu(h->bigdirnamelen) + 4) & ~3);
offset += dir->pos * sizeof(struct adfs_bigdirentry);
dir_memcpy(dir, offset, &bde, sizeof(struct adfs_bigdirentry));
obj->loadaddr = le32_to_cpu(bde.bigdirload);
obj->execaddr = le32_to_cpu(bde.bigdirexec);
obj->size = le32_to_cpu(bde.bigdirlen);
obj->file_id = le32_to_cpu(bde.bigdirindaddr);
obj->attr = le32_to_cpu(bde.bigdirattr);
obj->name_len = le32_to_cpu(bde.bigdirobnamelen);
offset = offsetof(struct adfs_bigdirheader, bigdirname);
offset += ((le32_to_cpu(h->bigdirnamelen) + 4) & ~3);
offset += le32_to_cpu(h->bigdirentries) * sizeof(struct adfs_bigdirentry);
offset += le32_to_cpu(bde.bigdirobnameptr);
dir_memcpy(dir, offset, obj->name, obj->name_len);
for (i = 0; i < obj->name_len; i++)
if (obj->name[i] == '/')
obj->name[i] = '.';
dir->pos += 1;
ret = 0;
out:
return ret;
}
static int
adfs_fplus_sync(struct adfs_dir *dir)
{
int err = 0;
int i;
for (i = dir->nr_buffers - 1; i >= 0; i--) {
struct buffer_head *bh = dir->bh[i];
sync_dirty_buffer(bh);
if (buffer_req(bh) && !buffer_uptodate(bh))
err = -EIO;
}
return err;
}
static void
adfs_fplus_free(struct adfs_dir *dir)
{
int i;
for (i = 0; i < dir->nr_buffers; i++)
brelse(dir->bh[i]);
dir->sb = NULL;
}
struct adfs_dir_ops adfs_fplus_dir_ops = {
.read = adfs_fplus_read,
.setpos = adfs_fplus_setpos,
.getnext = adfs_fplus_getnext,
.sync = adfs_fplus_sync,
.free = adfs_fplus_free
};
|
