xref: /openbmc/linux/fs/qnx4/dir.c (revision 65ee8aeb)
1 /*
2  * QNX4 file system, Linux implementation.
3  *
4  * Version : 0.2.1
5  *
6  * Using parts of the xiafs filesystem.
7  *
8  * History :
9  *
10  * 28-05-1998 by Richard Frowijn : first release.
11  * 20-06-1998 by Frank Denis : Linux 2.1.99+ & dcache support.
12  */
13 
14 #include <linux/buffer_head.h>
15 #include "qnx4.h"
16 
17 static int qnx4_readdir(struct file *file, struct dir_context *ctx)
18 {
19 	struct inode *inode = file_inode(file);
20 	unsigned int offset;
21 	struct buffer_head *bh;
22 	struct qnx4_inode_entry *de;
23 	struct qnx4_link_info *le;
24 	unsigned long blknum;
25 	int ix, ino;
26 	int size;
27 
28 	QNX4DEBUG((KERN_INFO "qnx4_readdir:i_size = %ld\n", (long) inode->i_size));
29 	QNX4DEBUG((KERN_INFO "pos                 = %ld\n", (long) ctx->pos));
30 
31 	while (ctx->pos < inode->i_size) {
32 		blknum = qnx4_block_map(inode, ctx->pos >> QNX4_BLOCK_SIZE_BITS);
33 		bh = sb_bread(inode->i_sb, blknum);
34 		if (bh == NULL) {
35 			printk(KERN_ERR "qnx4_readdir: bread failed (%ld)\n", blknum);
36 			return 0;
37 		}
38 		ix = (ctx->pos >> QNX4_DIR_ENTRY_SIZE_BITS) % QNX4_INODES_PER_BLOCK;
39 		for (; ix < QNX4_INODES_PER_BLOCK; ix++, ctx->pos += QNX4_DIR_ENTRY_SIZE) {
40 			offset = ix * QNX4_DIR_ENTRY_SIZE;
41 			de = (struct qnx4_inode_entry *) (bh->b_data + offset);
42 			if (!de->di_fname[0])
43 				continue;
44 			if (!(de->di_status & (QNX4_FILE_USED|QNX4_FILE_LINK)))
45 				continue;
46 			if (!(de->di_status & QNX4_FILE_LINK))
47 				size = QNX4_SHORT_NAME_MAX;
48 			else
49 				size = QNX4_NAME_MAX;
50 			size = strnlen(de->di_fname, size);
51 			QNX4DEBUG((KERN_INFO "qnx4_readdir:%.*s\n", size, de->di_fname));
52 			if (!(de->di_status & QNX4_FILE_LINK))
53 				ino = blknum * QNX4_INODES_PER_BLOCK + ix - 1;
54 			else {
55 				le  = (struct qnx4_link_info*)de;
56 				ino = ( le32_to_cpu(le->dl_inode_blk) - 1 ) *
57 					QNX4_INODES_PER_BLOCK +
58 					le->dl_inode_ndx;
59 			}
60 			if (!dir_emit(ctx, de->di_fname, size, ino, DT_UNKNOWN)) {
61 				brelse(bh);
62 				return 0;
63 			}
64 		}
65 		brelse(bh);
66 	}
67 	return 0;
68 }
69 
70 const struct file_operations qnx4_dir_operations =
71 {
72 	.llseek		= generic_file_llseek,
73 	.read		= generic_read_dir,
74 	.iterate	= qnx4_readdir,
75 	.fsync		= generic_file_fsync,
76 };
77 
78 const struct inode_operations qnx4_dir_inode_operations =
79 {
80 	.lookup		= qnx4_lookup,
81 };
82