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/*
* linux/fs/efs/dir.c
*
* Copyright (C) 1998 Mike Shaver
*
* Portions derived from work (C) 1995,1996 Christian Vogelgsang.
* ``Inspired by'' fs/minix/dir.c.
*/
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/efs_fs.h>
#include <asm/uaccess.h>
static int efs_readdir(struct file *, void *, filldir_t);
int efs_lookup(struct inode *, struct dentry *);
static ssize_t
efs_dir_read(struct file *filp, char *buf, size_t count, loff_t *ppos)
{
return -EISDIR;
}
static struct file_operations efs_dir_ops = {
NULL, /* lseek */
efs_dir_read,
NULL, /* write */
efs_readdir,
NULL, /* poll */
NULL, /* ioctl */
NULL, /* mmap */
NULL, /* open */
NULL, /* flush */
NULL, /* release */
NULL /* fsync */
};
struct inode_operations efs_dir_inode_operations = {
&efs_dir_ops,
NULL, /* create */
efs_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,
NULL, /* truncate */
NULL /* permission */
};
static int
efs_readdir(struct file *filp, void *dirent, filldir_t filldir)
{
struct inode *in = filp->f_dentry->d_inode;
struct efs_inode_info *ini = &in->u.efs_i;
struct buffer_head *bh;
__u16 item;
__u32 block;
__u16 offset;
struct efs_dirblk *dirblk;
struct efs_dir_entry *entry;
if (!in || !in->i_sb || !S_ISDIR(in->i_mode) || !ini->tot)
return -EBADF;
if (ini->tot > 1) {
printk("EFS: ERROR: directory %s has %d extents\n",
filp->f_dentry->d_name.name, ini->tot);
printk("EFS: ERROR: Mike is lazy, so this is NYI.\n");
return 0;
};
if (in->i_size & (EFS_BLOCK_SIZE - 1))
printk("EFS: readdir: dirsize %#lx not block multiple\n", in->i_size);
/* filp->f_pos is (block << BLOCK_SIZE | item) */
block = filp->f_pos >> EFS_BLOCK_SIZE_BITS;
item = filp->f_pos & 0xFF;
start_block:
if (block == (in->i_size >> EFS_BLOCK_SIZE_BITS))
return 0; /* all done! */
bh = bread(in->i_dev, efs_bmap(in, block), EFS_BLOCK_SIZE);
if (!bh) {
printk("EFS: ERROR: readdir: bread of %#lx/%#x\n",
in->i_ino, efs_bmap(in, block));
return 0;
}
dirblk = (struct efs_dirblk *)bh->b_data;
/* skip empty slots */
do {
offset = EFS_SLOT2OFF(dirblk, item);
if (!offset) {
DB(("EFS: skipping empty slot %d\n", item));
}
item++;
if (item == dirblk->db_slots) {
item = 0;
block++;
if (!offset) {
brelse(bh);
goto start_block;
}
}
} while(!offset);
entry = EFS_DENT4OFF(dirblk, offset);
/*
DB(("EFS_SLOT2OFF(%d) -> %d, EFS_DENT4OFF(%p, %d) -> %p) || ",
item-1, offset, dirblk, offset, entry));
#ifdef DEBUG_EFS
{
__u8 *rawdirblk, nameptr;
__u32 iteminode;
__u16 namelen, rawdepos;
rawdirblk = (__u8*)bh->b_data;
rawdepos = (__u16)rawdirblk[EFS_DB_FIRST+item-1] << 1;
DB(("OLD_WAY: offset = %d, dent = %p ||", rawdepos,
(struct efs_dir_entry *)(rawdirblk + rawdepos)));
}
#endif
DB(("EFS: filldir(dirent, \"%.*s\", %d, %d, %d)\n",
entry->d_namelen, entry->d_name, entry->d_namelen,
filp->f_pos, efs_swab32(entry->ud_inum.l)));
*/
filldir(dirent, entry->d_name, entry->d_namelen, filp->f_pos,
efs_swab32(entry->ud_inum.l));
brelse(bh);
filp->f_pos = (block << EFS_BLOCK_SIZE_BITS) | item;
UPDATE_ATIME(in);
return 0;
}
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