4 * Copyright (c) 1999 Al Smith
7 #include <linux/buffer_head.h>
10 static int efs_readdir(struct file *, void *, filldir_t);
12 const struct file_operations efs_dir_operations = {
13 .llseek = generic_file_llseek,
14 .read = generic_read_dir,
15 .readdir = efs_readdir,
18 const struct inode_operations efs_dir_inode_operations = {
22 static int efs_readdir(struct file *filp, void *dirent, filldir_t filldir) {
23 struct inode *inode = filp->f_path.dentry->d_inode;
24 struct buffer_head *bh;
26 struct efs_dir *dirblock;
27 struct efs_dentry *dirslot;
33 if (inode->i_size & (EFS_DIRBSIZE-1))
34 printk(KERN_WARNING "EFS: WARNING: readdir(): directory size not a multiple of EFS_DIRBSIZE\n");
36 /* work out where this entry can be found */
37 block = filp->f_pos >> EFS_DIRBSIZE_BITS;
39 /* each block contains at most 256 slots */
40 slot = filp->f_pos & 0xff;
42 /* look at all blocks */
43 while (block < inode->i_blocks) {
44 /* read the dir block */
45 bh = sb_bread(inode->i_sb, efs_bmap(inode, block));
48 printk(KERN_ERR "EFS: readdir(): failed to read dir block %d\n", block);
52 dirblock = (struct efs_dir *) bh->b_data;
54 if (be16_to_cpu(dirblock->magic) != EFS_DIRBLK_MAGIC) {
55 printk(KERN_ERR "EFS: readdir(): invalid directory block\n");
60 while (slot < dirblock->slots) {
61 if (dirblock->space[slot] == 0) {
66 dirslot = (struct efs_dentry *) (((char *) bh->b_data) + EFS_SLOTAT(dirblock, slot));
68 inodenum = be32_to_cpu(dirslot->inode);
69 namelen = dirslot->namelen;
70 nameptr = dirslot->name;
73 printk(KERN_DEBUG "EFS: readdir(): block %d slot %d/%d: inode %u, name \"%s\", namelen %u\n", block, slot, dirblock->slots-1, inodenum, nameptr, namelen);
76 /* found the next entry */
77 filp->f_pos = (block << EFS_DIRBSIZE_BITS) | slot;
79 /* copy filename and data in dirslot */
80 filldir(dirent, nameptr, namelen, filp->f_pos, inodenum, DT_UNKNOWN);
83 if (nameptr - (char *) dirblock + namelen > EFS_DIRBSIZE) {
84 printk(KERN_WARNING "EFS: directory entry %d exceeds directory block\n", slot);
89 /* store position of next slot */
90 if (++slot == dirblock->slots) {
95 filp->f_pos = (block << EFS_DIRBSIZE_BITS) | slot;
106 filp->f_pos = (block << EFS_DIRBSIZE_BITS) | slot;