[deliverable/linux.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 <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,
	.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)
{
	int ret = 0;
#ifdef CONFIG_REISERFS_FS_XATTR
	struct dentry *privroot = REISERFS_SB(dir->d_sb)->priv_root;
	ret = (dir == dir->d_parent && privroot->d_inode &&
	       deh->deh_objectid == INODE_PKEY(privroot->d_inode)->k_objectid);
#endif
	return ret;
}

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