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
|
/*
* linux/fs/affs/dir.c
*
* (c) 1996 Hans-Joachim Widmaier - Rewritten
*
* (C) 1993 Ray Burr - Modified for Amiga FFS filesystem.
*
* (C) 1992 Eric Youngdale Modified for ISO 9660 filesystem.
*
* (C) 1991 Linus Torvalds - minix filesystem
*
* affs directory handling functions
*
*/
#define DEBUG 0
#include <asm/uaccess.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/kernel.h>
#include <linux/affs_fs.h>
#include <linux/stat.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/amigaffs.h>
static int affs_readdir(struct file *, void *, filldir_t);
static ssize_t affs_dir_read(struct file *, char *, size_t, loff_t *);
static struct file_operations affs_dir_operations = {
NULL, /* lseek - default */
affs_dir_read, /* read */
NULL, /* write - bad */
affs_readdir, /* readdir */
NULL, /* poll - default */
NULL, /* ioctl - default */
NULL, /* mmap */
NULL, /* no special open code */
NULL, /* flush */
NULL, /* no special release code */
file_fsync /* default fsync */
};
/*
* directories can handle most operations...
*/
struct inode_operations affs_dir_inode_operations = {
&affs_dir_operations, /* default directory file-ops */
affs_create, /* create */
affs_lookup, /* lookup */
affs_link, /* link */
affs_unlink, /* unlink */
affs_symlink, /* symlink */
affs_mkdir, /* mkdir */
affs_rmdir, /* rmdir */
NULL, /* mknod */
affs_rename, /* rename */
NULL, /* readlink */
NULL, /* follow_link */
NULL, /* readpage */
NULL, /* writepage */
NULL, /* bmap */
NULL, /* truncate */
NULL, /* permissions */
NULL, /* smap */
NULL /* revalidate */
};
static ssize_t
affs_dir_read(struct file *filp, char *buf, size_t count, loff_t *ppos)
{
return -EISDIR;
}
static int
affs_readdir(struct file *filp, void *dirent, filldir_t filldir)
{
int j, namelen;
s32 i;
int hash_pos;
int chain_pos;
unsigned long ino;
int stored;
unsigned char *name;
struct buffer_head *dir_bh;
struct buffer_head *fh_bh;
struct inode *dir;
struct inode *inode = filp->f_dentry->d_inode;
pr_debug("AFFS: readdir(ino=%lu,f_pos=%lu)\n",inode->i_ino,(unsigned long)filp->f_pos);
stored = 0;
dir_bh = NULL;
fh_bh = NULL;
dir = NULL;
ino = inode->i_ino;
if (filp->f_pos == 0) {
filp->private_data = (void *)0;
if (filldir(dirent,".",1,filp->f_pos,inode->i_ino) < 0) {
return 0;
}
++filp->f_pos;
stored++;
}
if (filp->f_pos == 1) {
if (filldir(dirent,"..",2,filp->f_pos,affs_parent_ino(inode)) < 0) {
return stored;
}
filp->f_pos = 2;
stored++;
}
chain_pos = (filp->f_pos - 2) & 0xffff;
hash_pos = (filp->f_pos - 2) >> 16;
if (chain_pos == 0xffff) {
affs_warning(inode->i_sb,"readdir","More than 65535 entries in chain");
chain_pos = 0;
hash_pos++;
filp->f_pos = ((hash_pos << 16) | chain_pos) + 2;
}
if (!(dir_bh = affs_bread(inode->i_dev,inode->i_ino,
AFFS_I2BSIZE(inode))))
goto readdir_done;
while (1) {
while (hash_pos < AFFS_I2HSIZE(inode) &&
!((struct dir_front *)dir_bh->b_data)->hashtable[hash_pos])
hash_pos++;
if (hash_pos >= AFFS_I2HSIZE(inode))
break;
i = be32_to_cpu(((struct dir_front *)dir_bh->b_data)->hashtable[hash_pos]);
j = chain_pos;
/* If the directory hasn't changed since the last call to readdir(),
* we can jump directly to where we left off.
*/
if (filp->private_data && filp->f_version == inode->i_version) {
i = (s32)filp->private_data;
j = 0;
pr_debug("AFFS: readdir() left off=%d\n",i);
}
filp->f_version = inode->i_version;
pr_debug("AFFS: hash_pos=%d chain_pos=%d\n",hash_pos,chain_pos);
while (i) {
if (!(fh_bh = affs_bread(inode->i_dev,i,AFFS_I2BSIZE(inode)))) {
affs_error(inode->i_sb,"readdir","Cannot read block %d",i);
goto readdir_done;
}
ino = i;
i = be32_to_cpu(FILE_END(fh_bh->b_data,inode)->hash_chain);
if (j == 0)
break;
affs_brelse(fh_bh);
fh_bh = NULL;
j--;
}
if (fh_bh) {
namelen = affs_get_file_name(AFFS_I2BSIZE(inode),fh_bh->b_data,&name);
pr_debug("AFFS: readdir(): filldir(\"%.*s\",ino=%lu), i=%d\n",
namelen,name,ino,i);
filp->private_data = (void *)ino;
if (filldir(dirent,name,namelen,filp->f_pos,ino) < 0)
goto readdir_done;
filp->private_data = (void *)i;
affs_brelse(fh_bh);
fh_bh = NULL;
stored++;
}
if (i == 0) {
hash_pos++;
chain_pos = 0;
} else
chain_pos++;
filp->f_pos = ((hash_pos << 16) | chain_pos) + 2;
}
readdir_done:
affs_brelse(dir_bh);
affs_brelse(fh_bh);
pr_debug("AFFS: readdir()=%d\n",stored);
return stored;
}
|
