1// SPDX-License-Identifier: GPL-2.0
2/*
3 * QNX4 file system, Linux implementation.
4 *
5 * Version : 0.2.1
6 *
7 * Using parts of the xiafs filesystem.
8 *
9 * History :
10 *
11 * 28-05-1998 by Richard Frowijn : first release.
12 * 20-06-1998 by Frank Denis : Linux 2.1.99+ & dcache support.
13 */
14
15#include <linux/buffer_head.h>
16#include "qnx4.h"
17
18static int qnx4_readdir(struct file *file, struct dir_context *ctx)
19{
20 struct inode *inode = file_inode(f: file);
21 unsigned int offset;
22 struct buffer_head *bh;
23 unsigned long blknum;
24 int ix, ino;
25 int size;
26
27 QNX4DEBUG((KERN_INFO "qnx4_readdir:i_size = %ld\n", (long) inode->i_size));
28 QNX4DEBUG((KERN_INFO "pos = %ld\n", (long) ctx->pos));
29
30 while (ctx->pos < inode->i_size) {
31 blknum = qnx4_block_map(inode, iblock: ctx->pos >> QNX4_BLOCK_SIZE_BITS);
32 bh = sb_bread(sb: inode->i_sb, block: blknum);
33 if (bh == NULL) {
34 printk(KERN_ERR "qnx4_readdir: bread failed (%ld)\n", blknum);
35 return 0;
36 }
37 ix = (ctx->pos >> QNX4_DIR_ENTRY_SIZE_BITS) % QNX4_INODES_PER_BLOCK;
38 for (; ix < QNX4_INODES_PER_BLOCK; ix++, ctx->pos += QNX4_DIR_ENTRY_SIZE) {
39 union qnx4_directory_entry *de;
40 const char *fname;
41
42 offset = ix * QNX4_DIR_ENTRY_SIZE;
43 de = (union qnx4_directory_entry *) (bh->b_data + offset);
44
45 fname = get_entry_fname(de, size: &size);
46 if (!fname)
47 continue;
48
49 if (!(de->de_status & QNX4_FILE_LINK)) {
50 ino = blknum * QNX4_INODES_PER_BLOCK + ix - 1;
51 } else {
52 ino = ( le32_to_cpu(de->link.dl_inode_blk) - 1 ) *
53 QNX4_INODES_PER_BLOCK +
54 de->link.dl_inode_ndx;
55 }
56
57 QNX4DEBUG((KERN_INFO "qnx4_readdir:%.*s\n", size, fname));
58 if (!dir_emit(ctx, name: fname, namelen: size, ino, DT_UNKNOWN)) {
59 brelse(bh);
60 return 0;
61 }
62 }
63 brelse(bh);
64 }
65 return 0;
66}
67
68const struct file_operations qnx4_dir_operations =
69{
70 .llseek = generic_file_llseek,
71 .read = generic_read_dir,
72 .iterate_shared = qnx4_readdir,
73 .fsync = generic_file_fsync,
74};
75
76const struct inode_operations qnx4_dir_inode_operations =
77{
78 .lookup = qnx4_lookup,
79};
80

source code of linux/fs/qnx4/dir.c