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
qnx4_readdir(struct file * file,struct dir_context * ctx)18 static int qnx4_readdir(struct file *file, struct dir_context *ctx)
19 {
20 struct inode *inode = file_inode(file);
21 unsigned int offset;
22 struct buffer_head *bh;
23 struct qnx4_inode_entry *de;
24 struct qnx4_link_info *le;
25 unsigned long blknum;
26 int ix, ino;
27 int size;
28
29 QNX4DEBUG((KERN_INFO "qnx4_readdir:i_size = %ld\n", (long) inode->i_size));
30 QNX4DEBUG((KERN_INFO "pos = %ld\n", (long) ctx->pos));
31
32 while (ctx->pos < inode->i_size) {
33 blknum = qnx4_block_map(inode, ctx->pos >> QNX4_BLOCK_SIZE_BITS);
34 bh = sb_bread(inode->i_sb, blknum);
35 if (bh == NULL) {
36 printk(KERN_ERR "qnx4_readdir: bread failed (%ld)\n", blknum);
37 return 0;
38 }
39 ix = (ctx->pos >> QNX4_DIR_ENTRY_SIZE_BITS) % QNX4_INODES_PER_BLOCK;
40 for (; ix < QNX4_INODES_PER_BLOCK; ix++, ctx->pos += QNX4_DIR_ENTRY_SIZE) {
41 offset = ix * QNX4_DIR_ENTRY_SIZE;
42 de = (struct qnx4_inode_entry *) (bh->b_data + offset);
43 if (!de->di_fname[0])
44 continue;
45 if (!(de->di_status & (QNX4_FILE_USED|QNX4_FILE_LINK)))
46 continue;
47 if (!(de->di_status & QNX4_FILE_LINK))
48 size = QNX4_SHORT_NAME_MAX;
49 else
50 size = QNX4_NAME_MAX;
51 size = strnlen(de->di_fname, size);
52 QNX4DEBUG((KERN_INFO "qnx4_readdir:%.*s\n", size, de->di_fname));
53 if (!(de->di_status & QNX4_FILE_LINK))
54 ino = blknum * QNX4_INODES_PER_BLOCK + ix - 1;
55 else {
56 le = (struct qnx4_link_info*)de;
57 ino = ( le32_to_cpu(le->dl_inode_blk) - 1 ) *
58 QNX4_INODES_PER_BLOCK +
59 le->dl_inode_ndx;
60 }
61 if (!dir_emit(ctx, de->di_fname, size, ino, DT_UNKNOWN)) {
62 brelse(bh);
63 return 0;
64 }
65 }
66 brelse(bh);
67 }
68 return 0;
69 }
70
71 const struct file_operations qnx4_dir_operations =
72 {
73 .llseek = generic_file_llseek,
74 .read = generic_read_dir,
75 .iterate_shared = qnx4_readdir,
76 .fsync = generic_file_fsync,
77 };
78
79 const struct inode_operations qnx4_dir_inode_operations =
80 {
81 .lookup = qnx4_lookup,
82 };
83