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/*
* dir.c
*
* Copyright (c) 1999 Al Smith
*/
#include <linux/efs_fs.h>
static int efs_readdir(struct file *, void *, filldir_t);
static struct file_operations efs_dir_operations = {
NULL, /* lseek */
NULL, /* read */
NULL, /* write */
efs_readdir, /* readdir */
NULL, /* poll */
NULL, /* ioctl */
NULL, /* mmap */
NULL, /* open */
NULL, /* flush */
NULL, /* release */
NULL, /* fsync */
NULL, /* fasync */
NULL, /* check_media_change */
NULL /* revalidate */
};
struct inode_operations efs_dir_inode_operations = {
&efs_dir_operations, /* default directory file-ops */
NULL, /* create */
efs_lookup, /* lookup */
NULL, /* link */
NULL, /* unlink */
NULL, /* symlink */
NULL, /* mkdir */
NULL, /* rmdir */
NULL, /* mknod */
NULL, /* rename */
NULL, /* readlink */
NULL, /* follow_link */
NULL, /* readpage */
NULL, /* writepage */
efs_bmap, /* bmap */
NULL, /* truncate */
NULL, /* permission */
NULL /* smap */
};
static int efs_readdir(struct file *filp, void *dirent, filldir_t filldir) {
struct inode *inode = filp->f_dentry->d_inode;
struct buffer_head *bh;
struct efs_dir *dirblock;
struct efs_dentry *dirslot;
efs_ino_t inodenum;
efs_block_t block;
int slot, namelen;
char *nameptr;
if (!inode || !S_ISDIR(inode->i_mode))
return -EBADF;
if (inode->i_size & (EFS_DIRBSIZE-1))
printk("EFS: WARNING: readdir(): directory size not a multiple of EFS_DIRBSIZE\n");
/* work out where this entry can be found */
block = filp->f_pos >> EFS_DIRBSIZE_BITS;
/* each block contains at most 256 slots */
slot = filp->f_pos & 0xff;
/* look at all blocks */
while (block < inode->i_blocks) {
/* read the dir block */
bh = bread(inode->i_dev, efs_bmap(inode, block), EFS_DIRBSIZE);
if (!bh) {
printk("EFS: readdir(): failed to read dir block %d\n", block);
break;
}
dirblock = (struct efs_dir *) bh->b_data;
if (be16_to_cpu(dirblock->magic) != EFS_DIRBLK_MAGIC) {
printk("EFS: readdir(): invalid directory block\n");
brelse(bh);
break;
}
while(slot < dirblock->slots) {
if (dirblock->space[slot] == 0) {
slot++;
continue;
}
dirslot = (struct efs_dentry *) (((char *) bh->b_data) + EFS_SLOTAT(dirblock, slot));
inodenum = be32_to_cpu(dirslot->inode);
namelen = dirslot->namelen;
nameptr = dirslot->name;
#ifdef DEBUG
printk("EFS: readdir(): block %d slot %d/%d: inode %u, name \"%s\", namelen %u\n", block, slot, dirblock->slots-1, inodenum, nameptr, namelen);
#endif
if (namelen > 0) {
/* found the next entry */
filp->f_pos = (block << EFS_DIRBSIZE_BITS) | slot;
/* copy filename and data in dirslot */
filldir(dirent, nameptr, namelen, filp->f_pos, inodenum);
/* store position of next slot */
if (++slot == dirblock->slots) {
slot = 0;
block++;
}
brelse(bh);
filp->f_pos = (block << EFS_DIRBSIZE_BITS) | slot;
return 0;
}
slot++;
}
brelse(bh);
slot = 0;
block++;
}
filp->f_pos = (block << EFS_DIRBSIZE_BITS) | slot;
return 0;
}
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