dir.c
2.12 KB
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
/*
* QNX4 file system, Linux implementation.
*
* Version : 0.2.1
*
* Using parts of the xiafs filesystem.
*
* History :
*
* 28-05-1998 by Richard Frowijn : first release.
* 20-06-1998 by Frank Denis : Linux 2.1.99+ & dcache support.
*/
#include <linux/buffer_head.h>
#include "qnx4.h"
static int qnx4_readdir(struct file *file, struct dir_context *ctx)
{
struct inode *inode = file_inode(file);
unsigned int offset;
struct buffer_head *bh;
struct qnx4_inode_entry *de;
struct qnx4_link_info *le;
unsigned long blknum;
int ix, ino;
int size;
QNX4DEBUG((KERN_INFO "qnx4_readdir:i_size = %ld\n", (long) inode->i_size));
QNX4DEBUG((KERN_INFO "pos = %ld\n", (long) ctx->pos));
while (ctx->pos < inode->i_size) {
blknum = qnx4_block_map(inode, ctx->pos >> QNX4_BLOCK_SIZE_BITS);
bh = sb_bread(inode->i_sb, blknum);
if (bh == NULL) {
printk(KERN_ERR "qnx4_readdir: bread failed (%ld)\n", blknum);
return 0;
}
ix = (ctx->pos >> QNX4_DIR_ENTRY_SIZE_BITS) % QNX4_INODES_PER_BLOCK;
for (; ix < QNX4_INODES_PER_BLOCK; ix++, ctx->pos += QNX4_DIR_ENTRY_SIZE) {
offset = ix * QNX4_DIR_ENTRY_SIZE;
de = (struct qnx4_inode_entry *) (bh->b_data + offset);
if (!de->di_fname[0])
continue;
if (!(de->di_status & (QNX4_FILE_USED|QNX4_FILE_LINK)))
continue;
if (!(de->di_status & QNX4_FILE_LINK))
size = QNX4_SHORT_NAME_MAX;
else
size = QNX4_NAME_MAX;
size = strnlen(de->di_fname, size);
QNX4DEBUG((KERN_INFO "qnx4_readdir:%.*s\n", size, de->di_fname));
if (!(de->di_status & QNX4_FILE_LINK))
ino = blknum * QNX4_INODES_PER_BLOCK + ix - 1;
else {
le = (struct qnx4_link_info*)de;
ino = ( le32_to_cpu(le->dl_inode_blk) - 1 ) *
QNX4_INODES_PER_BLOCK +
le->dl_inode_ndx;
}
if (!dir_emit(ctx, de->di_fname, size, ino, DT_UNKNOWN)) {
brelse(bh);
return 0;
}
}
brelse(bh);
}
return 0;
}
const struct file_operations qnx4_dir_operations =
{
.llseek = generic_file_llseek,
.read = generic_read_dir,
.iterate = qnx4_readdir,
.fsync = generic_file_fsync,
};
const struct inode_operations qnx4_dir_inode_operations =
{
.lookup = qnx4_lookup,
};