[linux-2.6-block.git] / fs / reiserfs / dir.c

/*
 * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README
 */

#include <linux/string.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/reiserfs_fs.h>
#include <linux/stat.h>
#include <linux/buffer_head.h>
#include <linux/slab.h>
#include <asm/uaccess.h>

extern const struct reiserfs_key MIN_KEY;

static int reiserfs_readdir(struct file *, void *, filldir_t);
static int reiserfs_dir_fsync(struct file *filp, struct dentry *dentry,
			      int datasync);

const struct file_operations reiserfs_dir_operations = {
	.read = generic_read_dir,
	.readdir = reiserfs_readdir,
	.fsync = reiserfs_dir_fsync,
	.unlocked_ioctl = reiserfs_ioctl,
#ifdef CONFIG_COMPAT
	.compat_ioctl = reiserfs_compat_ioctl,
#endif
};

static int reiserfs_dir_fsync(struct file *filp, struct dentry *dentry,
			      int datasync)
{
	struct inode *inode = dentry->d_inode;
	int err;
	reiserfs_write_lock(inode->i_sb);
	err = reiserfs_commit_for_inode(inode);
	reiserfs_write_unlock(inode->i_sb);
	if (err < 0)
		return err;
	return 0;
}

#define store_ih(where,what) copy_item_head (where, what)

static inline bool is_privroot_deh(struct dentry *dir,
				   struct reiserfs_de_head *deh)
{
	struct dentry *privroot = REISERFS_SB(dir->d_sb)->priv_root;
	return (dir == dir->d_parent && privroot->d_inode &&
	        deh->deh_objectid == INODE_PKEY(privroot->d_inode)->k_objectid);
}

int reiserfs_readdir_dentry(struct dentry *dentry, void *dirent,
			   filldir_t filldir, loff_t *pos)
{
	struct inode *inode = dentry->d_inode;
	struct cpu_key pos_key;	/* key of current position in the directory (key of directory entry) */
	INITIALIZE_PATH(path_to_entry);
	struct buffer_head *bh;
	int item_num, entry_num;
	const struct reiserfs_key *rkey;
	struct item_head *ih, tmp_ih;
	int search_res;
	char *local_buf;
	loff_t next_pos;
	char small_buf[32];	/* avoid kmalloc if we can */
	struct reiserfs_dir_entry de;
	int ret = 0;

	reiserfs_write_lock(inode->i_sb);

	reiserfs_check_lock_depth(inode->i_sb, "readdir");

	/* form key for search the next directory entry using f_pos field of
	   file structure */
	make_cpu_key(&pos_key, inode, *pos ?: DOT_OFFSET, TYPE_DIRENTRY, 3);
	next_pos = cpu_key_k_offset(&pos_key);

	path_to_entry.reada = PATH_READA;
	while (1) {
	      research:
		/* search the directory item, containing entry with specified key */
		search_res =
		    search_by_entry_key(inode->i_sb, &pos_key, &path_to_entry,
					&de);
		if (search_res == IO_ERROR) {
			// FIXME: we could just skip part of directory which could
			// not be read
			ret = -EIO;
			goto out;
		}
		entry_num = de.de_entry_num;
		bh = de.de_bh;
		item_num = de.de_item_num;
		ih = de.de_ih;
		store_ih(&tmp_ih, ih);

		/* we must have found item, that is item of this directory, */
		RFALSE(COMP_SHORT_KEYS(&(ih->ih_key), &pos_key),
		       "vs-9000: found item %h does not match to dir we readdir %K",
		       ih, &pos_key);
		RFALSE(item_num > B_NR_ITEMS(bh) - 1,
		       "vs-9005 item_num == %d, item amount == %d",
		       item_num, B_NR_ITEMS(bh));

		/* and entry must be not more than number of entries in the item */
		RFALSE(I_ENTRY_COUNT(ih) < entry_num,
		       "vs-9010: entry number is too big %d (%d)",
		       entry_num, I_ENTRY_COUNT(ih));

		if (search_res == POSITION_FOUND
		    || entry_num < I_ENTRY_COUNT(ih)) {
			/* go through all entries in the directory item beginning from the entry, that has been found */
			struct reiserfs_de_head *deh =
			    B_I_DEH(bh, ih) + entry_num;

			for (; entry_num < I_ENTRY_COUNT(ih);
			     entry_num++, deh++) {
				int d_reclen;
				char *d_name;
				off_t d_off;
				ino_t d_ino;

				if (!de_visible(deh))
					/* it is hidden entry */
					continue;
				d_reclen = entry_length(bh, ih, entry_num);
				d_name = B_I_DEH_ENTRY_FILE_NAME(bh, ih, deh);

				if (d_reclen <= 0 ||
				    d_name + d_reclen > bh->b_data + bh->b_size) {
					/* There is corrupted data in entry,
					 * We'd better stop here */
					pathrelse(&path_to_entry);
					ret = -EIO;
					goto out;
				}

				if (!d_name[d_reclen - 1])
					d_reclen = strlen(d_name);

				if (d_reclen >
				    REISERFS_MAX_NAME(inode->i_sb->
						      s_blocksize)) {
					/* too big to send back to VFS */
					continue;
				}

				/* Ignore the .reiserfs_priv entry */
				if (is_privroot_deh(dentry, deh))
					continue;

				d_off = deh_offset(deh);
				*pos = d_off;
				d_ino = deh_objectid(deh);
				if (d_reclen <= 32) {
					local_buf = small_buf;
				} else {
					local_buf = kmalloc(d_reclen,
							    GFP_NOFS);
					if (!local_buf) {
						pathrelse(&path_to_entry);
						ret = -ENOMEM;
						goto out;
					}
					if (item_moved(&tmp_ih, &path_to_entry)) {
						kfree(local_buf);
						goto research;
					}
				}
				// Note, that we copy name to user space via temporary
				// buffer (local_buf) because filldir will block if
				// user space buffer is swapped out. At that time
				// entry can move to somewhere else
				memcpy(local_buf, d_name, d_reclen);

				/*
				 * Since filldir might sleep, we can release
				 * the write lock here for other waiters
				 */
				reiserfs_write_unlock(inode->i_sb);
				if (filldir
				    (dirent, local_buf, d_reclen, d_off, d_ino,
				     DT_UNKNOWN) < 0) {
					reiserfs_write_lock(inode->i_sb);
					if (local_buf != small_buf) {
						kfree(local_buf);
					}
					goto end;
				}
				reiserfs_write_lock(inode->i_sb);
				if (local_buf != small_buf) {
					kfree(local_buf);
				}
				// next entry should be looked for with such offset
				next_pos = deh_offset(deh) + 1;

				if (item_moved(&tmp_ih, &path_to_entry)) {
					goto research;
				}
			}	/* for */
		}

		if (item_num != B_NR_ITEMS(bh) - 1)
			// end of directory has been reached
			goto end;

		/* item we went through is last item of node. Using right
		   delimiting key check is it directory end */
		rkey = get_rkey(&path_to_entry, inode->i_sb);
		if (!comp_le_keys(rkey, &MIN_KEY)) {
			/* set pos_key to key, that is the smallest and greater
			   that key of the last entry in the item */
			set_cpu_key_k_offset(&pos_key, next_pos);
			continue;
		}

		if (COMP_SHORT_KEYS(rkey, &pos_key)) {
			// end of directory has been reached
			goto end;
		}

		/* directory continues in the right neighboring block */
		set_cpu_key_k_offset(&pos_key,
				     le_key_k_offset(KEY_FORMAT_3_5, rkey));

	}			/* while */

end:
	*pos = next_pos;
	pathrelse(&path_to_entry);
	reiserfs_check_path(&path_to_entry);
out:
	reiserfs_write_unlock(inode->i_sb);
	return ret;
}

static int reiserfs_readdir(struct file *file, void *dirent, filldir_t filldir)
{
	struct dentry *dentry = file->f_path.dentry;
	return reiserfs_readdir_dentry(dentry, dirent, filldir, &file->f_pos);
}

/* compose directory item containing "." and ".." entries (entries are
   not aligned to 4 byte boundary) */
/* the last four params are LE */
void make_empty_dir_item_v1(char *body, __le32 dirid, __le32 objid,
			    __le32 par_dirid, __le32 par_objid)
{
	struct reiserfs_de_head *deh;

	memset(body, 0, EMPTY_DIR_SIZE_V1);
	deh = (struct reiserfs_de_head *)body;

	/* direntry header of "." */
	put_deh_offset(&(deh[0]), DOT_OFFSET);
	/* these two are from make_le_item_head, and are are LE */
	deh[0].deh_dir_id = dirid;
	deh[0].deh_objectid = objid;
	deh[0].deh_state = 0;	/* Endian safe if 0 */
	put_deh_location(&(deh[0]), EMPTY_DIR_SIZE_V1 - strlen("."));
	mark_de_visible(&(deh[0]));

	/* direntry header of ".." */
	put_deh_offset(&(deh[1]), DOT_DOT_OFFSET);
	/* key of ".." for the root directory */
	/* these two are from the inode, and are are LE */
	deh[1].deh_dir_id = par_dirid;
	deh[1].deh_objectid = par_objid;
	deh[1].deh_state = 0;	/* Endian safe if 0 */
	put_deh_location(&(deh[1]), deh_location(&(deh[0])) - strlen(".."));
	mark_de_visible(&(deh[1]));

	/* copy ".." and "." */
	memcpy(body + deh_location(&(deh[0])), ".", 1);
	memcpy(body + deh_location(&(deh[1])), "..", 2);
}

/* compose directory item containing "." and ".." entries */
void make_empty_dir_item(char *body, __le32 dirid, __le32 objid,
			 __le32 par_dirid, __le32 par_objid)
{
	struct reiserfs_de_head *deh;

	memset(body, 0, EMPTY_DIR_SIZE);
	deh = (struct reiserfs_de_head *)body;

	/* direntry header of "." */
	put_deh_offset(&(deh[0]), DOT_OFFSET);
	/* these two are from make_le_item_head, and are are LE */
	deh[0].deh_dir_id = dirid;
	deh[0].deh_objectid = objid;
	deh[0].deh_state = 0;	/* Endian safe if 0 */
	put_deh_location(&(deh[0]), EMPTY_DIR_SIZE - ROUND_UP(strlen(".")));
	mark_de_visible(&(deh[0]));

	/* direntry header of ".." */
	put_deh_offset(&(deh[1]), DOT_DOT_OFFSET);
	/* key of ".." for the root directory */
	/* these two are from the inode, and are are LE */
	deh[1].deh_dir_id = par_dirid;
	deh[1].deh_objectid = par_objid;
	deh[1].deh_state = 0;	/* Endian safe if 0 */
	put_deh_location(&(deh[1]),
			 deh_location(&(deh[0])) - ROUND_UP(strlen("..")));
	mark_de_visible(&(deh[1]));

	/* copy ".." and "." */
	memcpy(body + deh_location(&(deh[0])), ".", 1);
	memcpy(body + deh_location(&(deh[1])), "..", 2);
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README
	3	*/
	4
1da177e4 LT	5	#include <linux/string.h>
	6	#include <linux/errno.h>
	7	#include <linux/fs.h>
	8	#include <linux/reiserfs_fs.h>
	9	#include <linux/stat.h>
1da177e4	10	#include <linux/buffer_head.h>
5a0e3ad6	11	#include <linux/slab.h>
1da177e4 LT	12	#include <asm/uaccess.h>
1da177e4 LT	13
5a1b6391	14	extern const struct reiserfs_key MIN_KEY;
1da177e4	15
bd4c625c LT	16	static int reiserfs_readdir(struct file , void , filldir_t);
	17	static int reiserfs_dir_fsync(struct file filp, struct dentry dentry,
	18	int datasync);
1da177e4	19
4b6f5d20	20	const struct file_operations reiserfs_dir_operations = {
bd4c625c LT	21	.read = generic_read_dir,
	22	.readdir = reiserfs_readdir,
	23	.fsync = reiserfs_dir_fsync,
205cb37b	24	.unlocked_ioctl = reiserfs_ioctl,
52b499c4 DH	25	#ifdef CONFIG_COMPAT
	26	.compat_ioctl = reiserfs_compat_ioctl,
	27	#endif
1da177e4 LT	28	};
1da177e4 LT	29
bd4c625c LT	30	static int reiserfs_dir_fsync(struct file filp, struct dentry dentry,
	31	int datasync)
	32	{
	33	struct inode *inode = dentry->d_inode;
	34	int err;
	35	reiserfs_write_lock(inode->i_sb);
	36	err = reiserfs_commit_for_inode(inode);
	37	reiserfs_write_unlock(inode->i_sb);
	38	if (err < 0)
	39	return err;
	40	return 0;
1da177e4 LT	41	}
1da177e4 LT	42
1da177e4 LT	43	#define store_ih(where,what) copy_item_head (where, what)
1da177e4 LT	44
677c9b2e JM	45	static inline bool is_privroot_deh(struct dentry *dir,
	46	struct reiserfs_de_head *deh)
	47	{
677c9b2e	48	struct dentry *privroot = REISERFS_SB(dir->d_sb)->priv_root;
73422811 JM	49	return (dir == dir->d_parent && privroot->d_inode &&
73422811 JM	50	deh->deh_objectid == INODE_PKEY(privroot->d_inode)->k_objectid);
677c9b2e JM	51	}
677c9b2e JM	52
a41f1a47 JM	53	int reiserfs_readdir_dentry(struct dentry dentry, void dirent,
a41f1a47 JM	54	filldir_t filldir, loff_t *pos)
1da177e4	55	{
a41f1a47	56	struct inode *inode = dentry->d_inode;
bd4c625c LT	57	struct cpu_key pos_key; /* key of current position in the directory (key of directory entry) */
	58	INITIALIZE_PATH(path_to_entry);
	59	struct buffer_head *bh;
	60	int item_num, entry_num;
	61	const struct reiserfs_key *rkey;
	62	struct item_head *ih, tmp_ih;
	63	int search_res;
	64	char *local_buf;
	65	loff_t next_pos;
	66	char small_buf[32]; /* avoid kmalloc if we can */
	67	struct reiserfs_dir_entry de;
	68	int ret = 0;
	69
	70	reiserfs_write_lock(inode->i_sb);
	71
	72	reiserfs_check_lock_depth(inode->i_sb, "readdir");
	73
	74	/* form key for search the next directory entry using f_pos field of
	75	file structure */
a41f1a47	76	make_cpu_key(&pos_key, inode, *pos ?: DOT_OFFSET, TYPE_DIRENTRY, 3);
bd4c625c LT	77	next_pos = cpu_key_k_offset(&pos_key);
bd4c625c LT	78
bd4c625c LT	79	path_to_entry.reada = PATH_READA;
	80	while (1) {
	81	research:
	82	/* search the directory item, containing entry with specified key */
	83	search_res =
	84	search_by_entry_key(inode->i_sb, &pos_key, &path_to_entry,
	85	&de);
	86	if (search_res == IO_ERROR) {
	87	// FIXME: we could just skip part of directory which could
	88	// not be read
	89	ret = -EIO;
1da177e4	90	goto out;
1da177e4	91	}
bd4c625c LT	92	entry_num = de.de_entry_num;
	93	bh = de.de_bh;
	94	item_num = de.de_item_num;
	95	ih = de.de_ih;
	96	store_ih(&tmp_ih, ih);
	97
	98	/* we must have found item, that is item of this directory, */
	99	RFALSE(COMP_SHORT_KEYS(&(ih->ih_key), &pos_key),
	100	"vs-9000: found item %h does not match to dir we readdir %K",
	101	ih, &pos_key);
	102	RFALSE(item_num > B_NR_ITEMS(bh) - 1,
	103	"vs-9005 item_num == %d, item amount == %d",
	104	item_num, B_NR_ITEMS(bh));
	105
	106	/* and entry must be not more than number of entries in the item */
	107	RFALSE(I_ENTRY_COUNT(ih) < entry_num,
	108	"vs-9010: entry number is too big %d (%d)",
	109	entry_num, I_ENTRY_COUNT(ih));
	110
	111	if (search_res == POSITION_FOUND
	112	\|\| entry_num < I_ENTRY_COUNT(ih)) {
	113	/* go through all entries in the directory item beginning from the entry, that has been found */
	114	struct reiserfs_de_head *deh =
	115	B_I_DEH(bh, ih) + entry_num;
	116
	117	for (; entry_num < I_ENTRY_COUNT(ih);
	118	entry_num++, deh++) {
	119	int d_reclen;
	120	char *d_name;
	121	off_t d_off;
	122	ino_t d_ino;
	123
	124	if (!de_visible(deh))
	125	/* it is hidden entry */
	126	continue;
	127	d_reclen = entry_length(bh, ih, entry_num);
	128	d_name = B_I_DEH_ENTRY_FILE_NAME(bh, ih, deh);
80eb68d2 LW	129
	130	if (d_reclen <= 0 \|\|
	131	d_name + d_reclen > bh->b_data + bh->b_size) {
	132	/* There is corrupted data in entry,
	133	* We'd better stop here */
	134	pathrelse(&path_to_entry);
	135	ret = -EIO;
	136	goto out;
	137	}
	138
bd4c625c LT	139	if (!d_name[d_reclen - 1])
	140	d_reclen = strlen(d_name);
	141
	142	if (d_reclen >
	143	REISERFS_MAX_NAME(inode->i_sb->
	144	s_blocksize)) {
	145	/* too big to send back to VFS */
	146	continue;
	147	}
	148
	149	/* Ignore the .reiserfs_priv entry */
677c9b2e	150	if (is_privroot_deh(dentry, deh))
bd4c625c	151	continue;
bd4c625c LT	152
bd4c625c LT	153	d_off = deh_offset(deh);
a41f1a47	154	*pos = d_off;
bd4c625c LT	155	d_ino = deh_objectid(deh);
	156	if (d_reclen <= 32) {
	157	local_buf = small_buf;
	158	} else {
d739b42b PE	159	local_buf = kmalloc(d_reclen,
d739b42b PE	160	GFP_NOFS);
bd4c625c LT	161	if (!local_buf) {
	162	pathrelse(&path_to_entry);
	163	ret = -ENOMEM;
	164	goto out;
	165	}
	166	if (item_moved(&tmp_ih, &path_to_entry)) {
d739b42b	167	kfree(local_buf);
bd4c625c LT	168	goto research;
	169	}
	170	}
	171	// Note, that we copy name to user space via temporary
	172	// buffer (local_buf) because filldir will block if
	173	// user space buffer is swapped out. At that time
	174	// entry can move to somewhere else
	175	memcpy(local_buf, d_name, d_reclen);
8ebc4232 FW	176
	177	/*
	178	* Since filldir might sleep, we can release
	179	* the write lock here for other waiters
	180	*/
	181	reiserfs_write_unlock(inode->i_sb);
bd4c625c LT	182	if (filldir
	183	(dirent, local_buf, d_reclen, d_off, d_ino,
	184	DT_UNKNOWN) < 0) {
8ebc4232	185	reiserfs_write_lock(inode->i_sb);
bd4c625c	186	if (local_buf != small_buf) {
d739b42b	187	kfree(local_buf);
bd4c625c LT	188	}
	189	goto end;
	190	}
8ebc4232	191	reiserfs_write_lock(inode->i_sb);
bd4c625c	192	if (local_buf != small_buf) {
d739b42b	193	kfree(local_buf);
bd4c625c LT	194	}
	195	// next entry should be looked for with such offset
	196	next_pos = deh_offset(deh) + 1;
	197
	198	if (item_moved(&tmp_ih, &path_to_entry)) {
	199	goto research;
	200	}
	201	} /* for */
1da177e4 LT	202	}
1da177e4 LT	203
bd4c625c LT	204	if (item_num != B_NR_ITEMS(bh) - 1)
	205	// end of directory has been reached
	206	goto end;
	207
	208	/* item we went through is last item of node. Using right
	209	delimiting key check is it directory end */
	210	rkey = get_rkey(&path_to_entry, inode->i_sb);
	211	if (!comp_le_keys(rkey, &MIN_KEY)) {
	212	/* set pos_key to key, that is the smallest and greater
	213	that key of the last entry in the item */
	214	set_cpu_key_k_offset(&pos_key, next_pos);
	215	continue;
	216	}
1da177e4	217
bd4c625c LT	218	if (COMP_SHORT_KEYS(rkey, &pos_key)) {
	219	// end of directory has been reached
	220	goto end;
1da177e4	221	}
bd4c625c LT	222
	223	/* directory continues in the right neighboring block */
	224	set_cpu_key_k_offset(&pos_key,
	225	le_key_k_offset(KEY_FORMAT_3_5, rkey));
	226
	227	} /* while */
	228
a41f1a47 JM	229	end:
a41f1a47 JM	230	*pos = next_pos;
bd4c625c LT	231	pathrelse(&path_to_entry);
bd4c625c LT	232	reiserfs_check_path(&path_to_entry);
a41f1a47	233	out:
bd4c625c LT	234	reiserfs_write_unlock(inode->i_sb);
bd4c625c LT	235	return ret;
1da177e4 LT	236	}
1da177e4 LT	237
a41f1a47 JM	238	static int reiserfs_readdir(struct file file, void dirent, filldir_t filldir)
	239	{
	240	struct dentry *dentry = file->f_path.dentry;
	241	return reiserfs_readdir_dentry(dentry, dirent, filldir, &file->f_pos);
	242	}
	243
1da177e4 LT	244	/* compose directory item containing "." and ".." entries (entries are
	245	not aligned to 4 byte boundary) */
	246	/* the last four params are LE */
bd4c625c LT	247	void make_empty_dir_item_v1(char *body, __le32 dirid, __le32 objid,
bd4c625c LT	248	__le32 par_dirid, __le32 par_objid)
1da177e4	249	{
bd4c625c LT	250	struct reiserfs_de_head *deh;
	251
	252	memset(body, 0, EMPTY_DIR_SIZE_V1);
	253	deh = (struct reiserfs_de_head *)body;
	254
	255	/* direntry header of "." */
	256	put_deh_offset(&(deh[0]), DOT_OFFSET);
	257	/* these two are from make_le_item_head, and are are LE */
	258	deh[0].deh_dir_id = dirid;
	259	deh[0].deh_objectid = objid;
	260	deh[0].deh_state = 0; /* Endian safe if 0 */
	261	put_deh_location(&(deh[0]), EMPTY_DIR_SIZE_V1 - strlen("."));
	262	mark_de_visible(&(deh[0]));
	263
	264	/* direntry header of ".." */
	265	put_deh_offset(&(deh[1]), DOT_DOT_OFFSET);
	266	/* key of ".." for the root directory */
	267	/* these two are from the inode, and are are LE */
	268	deh[1].deh_dir_id = par_dirid;
	269	deh[1].deh_objectid = par_objid;
	270	deh[1].deh_state = 0; /* Endian safe if 0 */
	271	put_deh_location(&(deh[1]), deh_location(&(deh[0])) - strlen(".."));
	272	mark_de_visible(&(deh[1]));
	273
	274	/* copy ".." and "." */
	275	memcpy(body + deh_location(&(deh[0])), ".", 1);
	276	memcpy(body + deh_location(&(deh[1])), "..", 2);
1da177e4 LT	277	}
	278
	279	/* compose directory item containing "." and ".." entries */
bd4c625c LT	280	void make_empty_dir_item(char *body, __le32 dirid, __le32 objid,
bd4c625c LT	281	__le32 par_dirid, __le32 par_objid)
1da177e4	282	{
bd4c625c LT	283	struct reiserfs_de_head *deh;
	284
	285	memset(body, 0, EMPTY_DIR_SIZE);
	286	deh = (struct reiserfs_de_head *)body;
	287
	288	/* direntry header of "." */
	289	put_deh_offset(&(deh[0]), DOT_OFFSET);
	290	/* these two are from make_le_item_head, and are are LE */
	291	deh[0].deh_dir_id = dirid;
	292	deh[0].deh_objectid = objid;
	293	deh[0].deh_state = 0; /* Endian safe if 0 */
	294	put_deh_location(&(deh[0]), EMPTY_DIR_SIZE - ROUND_UP(strlen(".")));
	295	mark_de_visible(&(deh[0]));
	296
	297	/* direntry header of ".." */
	298	put_deh_offset(&(deh[1]), DOT_DOT_OFFSET);
	299	/* key of ".." for the root directory */
	300	/* these two are from the inode, and are are LE */
	301	deh[1].deh_dir_id = par_dirid;
	302	deh[1].deh_objectid = par_objid;
	303	deh[1].deh_state = 0; /* Endian safe if 0 */
	304	put_deh_location(&(deh[1]),
	305	deh_location(&(deh[0])) - ROUND_UP(strlen("..")));
	306	mark_de_visible(&(deh[1]));
	307
	308	/* copy ".." and "." */
	309	memcpy(body + deh_location(&(deh[0])), ".", 1);
	310	memcpy(body + deh_location(&(deh[1])), "..", 2);
1da177e4	311	}