xref: /linux/fs/qnx4/dir.c (revision 8fa5723aa7e053d498336b48448b292fc2e0458b)
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/string.h>
15 #include <linux/errno.h>
16 #include <linux/fs.h>
17 #include <linux/qnx4_fs.h>
18 #include <linux/stat.h>
19 #include <linux/smp_lock.h>
20 #include <linux/buffer_head.h>
21 
22 
23 static int qnx4_readdir(struct file *filp, void *dirent, filldir_t filldir)
24 {
25 	struct inode *inode = filp->f_path.dentry->d_inode;
26 	unsigned int offset;
27 	struct buffer_head *bh;
28 	struct qnx4_inode_entry *de;
29 	struct qnx4_link_info *le;
30 	unsigned long blknum;
31 	int ix, ino;
32 	int size;
33 
34 	QNX4DEBUG(("qnx4_readdir:i_size = %ld\n", (long) inode->i_size));
35 	QNX4DEBUG(("filp->f_pos         = %ld\n", (long) filp->f_pos));
36 
37 	lock_kernel();
38 
39 	while (filp->f_pos < inode->i_size) {
40 		blknum = qnx4_block_map( inode, filp->f_pos >> QNX4_BLOCK_SIZE_BITS );
41 		bh = sb_bread(inode->i_sb, blknum);
42 		if(bh==NULL) {
43 			printk(KERN_ERR "qnx4_readdir: bread failed (%ld)\n", blknum);
44 			break;
45 		}
46 		ix = (int)(filp->f_pos >> QNX4_DIR_ENTRY_SIZE_BITS) % QNX4_INODES_PER_BLOCK;
47 		while (ix < QNX4_INODES_PER_BLOCK) {
48 			offset = ix * QNX4_DIR_ENTRY_SIZE;
49 			de = (struct qnx4_inode_entry *) (bh->b_data + offset);
50 			size = strlen(de->di_fname);
51 			if (size) {
52 				if ( !( de->di_status & QNX4_FILE_LINK ) && size > QNX4_SHORT_NAME_MAX )
53 					size = QNX4_SHORT_NAME_MAX;
54 				else if ( size > QNX4_NAME_MAX )
55 					size = QNX4_NAME_MAX;
56 
57 				if ( ( de->di_status & (QNX4_FILE_USED|QNX4_FILE_LINK) ) != 0 ) {
58 					QNX4DEBUG(("qnx4_readdir:%.*s\n", size, de->di_fname));
59 					if ( ( de->di_status & QNX4_FILE_LINK ) == 0 )
60 						ino = blknum * QNX4_INODES_PER_BLOCK + ix - 1;
61 					else {
62 						le  = (struct qnx4_link_info*)de;
63 						ino = ( le32_to_cpu(le->dl_inode_blk) - 1 ) *
64 							QNX4_INODES_PER_BLOCK +
65 							le->dl_inode_ndx;
66 					}
67 					if (filldir(dirent, de->di_fname, size, filp->f_pos, ino, DT_UNKNOWN) < 0) {
68 						brelse(bh);
69 						goto out;
70 					}
71 				}
72 			}
73 			ix++;
74 			filp->f_pos += QNX4_DIR_ENTRY_SIZE;
75 		}
76 		brelse(bh);
77 	}
78 out:
79 	unlock_kernel();
80 	return 0;
81 }
82 
83 const struct file_operations qnx4_dir_operations =
84 {
85 	.read		= generic_read_dir,
86 	.readdir	= qnx4_readdir,
87 	.fsync		= file_fsync,
88 };
89 
90 const struct inode_operations qnx4_dir_inode_operations =
91 {
92 	.lookup		= qnx4_lookup,
93 #ifdef CONFIG_QNX4FS_RW
94 	.create		= qnx4_create,
95 	.unlink		= qnx4_unlink,
96 	.rmdir		= qnx4_rmdir,
97 #endif
98 };
99