[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 int reiserfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
{
	struct inode *inode = filp->f_path.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,
		     (filp->f_pos) ? (filp->f_pos) : DOT_OFFSET, TYPE_DIRENTRY,
		     3);
	next_pos = cpu_key_k_offset(&pos_key);

	/*  reiserfs_warning (inode->i_sb, "reiserfs_readdir 1: f_pos = %Ld", filp->f_pos); */

	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 (reiserfs_xattrs(inode->i_sb) &&
				    !old_format_only(inode->i_sb) &&
				    filp->f_path.dentry == inode->i_sb->s_root &&
				    REISERFS_SB(inode->i_sb)->priv_root &&
				    REISERFS_SB(inode->i_sb)->priv_root->d_inode
				    && deh_objectid(deh) ==
				    le32_to_cpu(INODE_PKEY
						(REISERFS_SB(inode->i_sb)->
						 priv_root->d_inode)->
						k_objectid)) {
					continue;
				}

				d_off = deh_offset(deh);
				filp->f_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:
	filp->f_pos = next_pos;
	pathrelse(&path_to_entry);
	reiserfs_check_path(&path_to_entry);
      out:
	reiserfs_write_unlock(inode->i_sb);
	return ret;
}

/* 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)
	43
	44	//
bd4c625c	45	static int reiserfs_readdir(struct file filp, void dirent, filldir_t filldir)
1da177e4	46	{
1fc5adbd	47	struct inode *inode = filp->f_path.dentry->d_inode;
bd4c625c LT	48	struct cpu_key pos_key; /* key of current position in the directory (key of directory entry) */
	49	INITIALIZE_PATH(path_to_entry);
	50	struct buffer_head *bh;
	51	int item_num, entry_num;
	52	const struct reiserfs_key *rkey;
	53	struct item_head *ih, tmp_ih;
	54	int search_res;
	55	char *local_buf;
	56	loff_t next_pos;
	57	char small_buf[32]; /* avoid kmalloc if we can */
	58	struct reiserfs_dir_entry de;
	59	int ret = 0;
	60
	61	reiserfs_write_lock(inode->i_sb);
	62
	63	reiserfs_check_lock_depth(inode->i_sb, "readdir");
	64
	65	/* form key for search the next directory entry using f_pos field of
	66	file structure */
	67	make_cpu_key(&pos_key, inode,
	68	(filp->f_pos) ? (filp->f_pos) : DOT_OFFSET, TYPE_DIRENTRY,
	69	3);
	70	next_pos = cpu_key_k_offset(&pos_key);
	71
	72	/* reiserfs_warning (inode->i_sb, "reiserfs_readdir 1: f_pos = %Ld", filp->f_pos); */
	73
	74	path_to_entry.reada = PATH_READA;
	75	while (1) {
	76	research:
	77	/* search the directory item, containing entry with specified key */
	78	search_res =
	79	search_by_entry_key(inode->i_sb, &pos_key, &path_to_entry,
	80	&de);
	81	if (search_res == IO_ERROR) {
	82	// FIXME: we could just skip part of directory which could
	83	// not be read
	84	ret = -EIO;
1da177e4	85	goto out;
1da177e4	86	}
bd4c625c LT	87	entry_num = de.de_entry_num;
	88	bh = de.de_bh;
	89	item_num = de.de_item_num;
	90	ih = de.de_ih;
	91	store_ih(&tmp_ih, ih);
	92
	93	/* we must have found item, that is item of this directory, */
	94	RFALSE(COMP_SHORT_KEYS(&(ih->ih_key), &pos_key),
	95	"vs-9000: found item %h does not match to dir we readdir %K",
	96	ih, &pos_key);
	97	RFALSE(item_num > B_NR_ITEMS(bh) - 1,
	98	"vs-9005 item_num == %d, item amount == %d",
	99	item_num, B_NR_ITEMS(bh));
	100
	101	/* and entry must be not more than number of entries in the item */
	102	RFALSE(I_ENTRY_COUNT(ih) < entry_num,
	103	"vs-9010: entry number is too big %d (%d)",
	104	entry_num, I_ENTRY_COUNT(ih));
	105
	106	if (search_res == POSITION_FOUND
	107	\|\| entry_num < I_ENTRY_COUNT(ih)) {
	108	/* go through all entries in the directory item beginning from the entry, that has been found */
	109	struct reiserfs_de_head *deh =
	110	B_I_DEH(bh, ih) + entry_num;
	111
	112	for (; entry_num < I_ENTRY_COUNT(ih);
	113	entry_num++, deh++) {
	114	int d_reclen;
	115	char *d_name;
	116	off_t d_off;
	117	ino_t d_ino;
	118
	119	if (!de_visible(deh))
	120	/* it is hidden entry */
	121	continue;
	122	d_reclen = entry_length(bh, ih, entry_num);
	123	d_name = B_I_DEH_ENTRY_FILE_NAME(bh, ih, deh);
80eb68d2 LW	124
	125	if (d_reclen <= 0 \|\|
	126	d_name + d_reclen > bh->b_data + bh->b_size) {
	127	/* There is corrupted data in entry,
	128	* We'd better stop here */
	129	pathrelse(&path_to_entry);
	130	ret = -EIO;
	131	goto out;
	132	}
	133
bd4c625c LT	134	if (!d_name[d_reclen - 1])
	135	d_reclen = strlen(d_name);
	136
	137	if (d_reclen >
	138	REISERFS_MAX_NAME(inode->i_sb->
	139	s_blocksize)) {
	140	/* too big to send back to VFS */
	141	continue;
	142	}
	143
	144	/* Ignore the .reiserfs_priv entry */
	145	if (reiserfs_xattrs(inode->i_sb) &&
	146	!old_format_only(inode->i_sb) &&
1fc5adbd	147	filp->f_path.dentry == inode->i_sb->s_root &&
bd4c625c LT	148	REISERFS_SB(inode->i_sb)->priv_root &&
	149	REISERFS_SB(inode->i_sb)->priv_root->d_inode
	150	&& deh_objectid(deh) ==
	151	le32_to_cpu(INODE_PKEY
	152	(REISERFS_SB(inode->i_sb)->
	153	priv_root->d_inode)->
	154	k_objectid)) {
	155	continue;
	156	}
	157
	158	d_off = deh_offset(deh);
	159	filp->f_pos = d_off;
	160	d_ino = deh_objectid(deh);
	161	if (d_reclen <= 32) {
	162	local_buf = small_buf;
	163	} else {
d739b42b PE	164	local_buf = kmalloc(d_reclen,
d739b42b PE	165	GFP_NOFS);
bd4c625c LT	166	if (!local_buf) {
	167	pathrelse(&path_to_entry);
	168	ret = -ENOMEM;
	169	goto out;
	170	}
	171	if (item_moved(&tmp_ih, &path_to_entry)) {
d739b42b	172	kfree(local_buf);
bd4c625c LT	173	goto research;
	174	}
	175	}
	176	// Note, that we copy name to user space via temporary
	177	// buffer (local_buf) because filldir will block if
	178	// user space buffer is swapped out. At that time
	179	// entry can move to somewhere else
	180	memcpy(local_buf, d_name, d_reclen);
	181	if (filldir
	182	(dirent, local_buf, d_reclen, d_off, d_ino,
	183	DT_UNKNOWN) < 0) {
	184	if (local_buf != small_buf) {
d739b42b	185	kfree(local_buf);
bd4c625c LT	186	}
	187	goto end;
	188	}
	189	if (local_buf != small_buf) {
d739b42b	190	kfree(local_buf);
bd4c625c LT	191	}
	192	// next entry should be looked for with such offset
	193	next_pos = deh_offset(deh) + 1;
	194
	195	if (item_moved(&tmp_ih, &path_to_entry)) {
	196	goto research;
	197	}
	198	} /* for */
1da177e4 LT	199	}
1da177e4 LT	200
bd4c625c LT	201	if (item_num != B_NR_ITEMS(bh) - 1)
	202	// end of directory has been reached
	203	goto end;
	204
	205	/* item we went through is last item of node. Using right
	206	delimiting key check is it directory end */
	207	rkey = get_rkey(&path_to_entry, inode->i_sb);
	208	if (!comp_le_keys(rkey, &MIN_KEY)) {
	209	/* set pos_key to key, that is the smallest and greater
	210	that key of the last entry in the item */
	211	set_cpu_key_k_offset(&pos_key, next_pos);
	212	continue;
	213	}
1da177e4	214
bd4c625c LT	215	if (COMP_SHORT_KEYS(rkey, &pos_key)) {
	216	// end of directory has been reached
	217	goto end;
1da177e4	218	}
bd4c625c LT	219
	220	/* directory continues in the right neighboring block */
	221	set_cpu_key_k_offset(&pos_key,
	222	le_key_k_offset(KEY_FORMAT_3_5, rkey));
	223
	224	} /* while */
	225
	226	end:
	227	filp->f_pos = next_pos;
	228	pathrelse(&path_to_entry);
	229	reiserfs_check_path(&path_to_entry);
	230	out:
	231	reiserfs_write_unlock(inode->i_sb);
	232	return ret;
1da177e4 LT	233	}
	234
	235	/* compose directory item containing "." and ".." entries (entries are
	236	not aligned to 4 byte boundary) */
	237	/* the last four params are LE */
bd4c625c LT	238	void make_empty_dir_item_v1(char *body, __le32 dirid, __le32 objid,
bd4c625c LT	239	__le32 par_dirid, __le32 par_objid)
1da177e4	240	{
bd4c625c LT	241	struct reiserfs_de_head *deh;
	242
	243	memset(body, 0, EMPTY_DIR_SIZE_V1);
	244	deh = (struct reiserfs_de_head *)body;
	245
	246	/* direntry header of "." */
	247	put_deh_offset(&(deh[0]), DOT_OFFSET);
	248	/* these two are from make_le_item_head, and are are LE */
	249	deh[0].deh_dir_id = dirid;
	250	deh[0].deh_objectid = objid;
	251	deh[0].deh_state = 0; /* Endian safe if 0 */
	252	put_deh_location(&(deh[0]), EMPTY_DIR_SIZE_V1 - strlen("."));
	253	mark_de_visible(&(deh[0]));
	254
	255	/* direntry header of ".." */
	256	put_deh_offset(&(deh[1]), DOT_DOT_OFFSET);
	257	/* key of ".." for the root directory */
	258	/* these two are from the inode, and are are LE */
	259	deh[1].deh_dir_id = par_dirid;
	260	deh[1].deh_objectid = par_objid;
	261	deh[1].deh_state = 0; /* Endian safe if 0 */
	262	put_deh_location(&(deh[1]), deh_location(&(deh[0])) - strlen(".."));
	263	mark_de_visible(&(deh[1]));
	264
	265	/* copy ".." and "." */
	266	memcpy(body + deh_location(&(deh[0])), ".", 1);
	267	memcpy(body + deh_location(&(deh[1])), "..", 2);
1da177e4 LT	268	}
	269
	270	/* compose directory item containing "." and ".." entries */
bd4c625c LT	271	void make_empty_dir_item(char *body, __le32 dirid, __le32 objid,
bd4c625c LT	272	__le32 par_dirid, __le32 par_objid)
1da177e4	273	{
bd4c625c LT	274	struct reiserfs_de_head *deh;
	275
	276	memset(body, 0, EMPTY_DIR_SIZE);
	277	deh = (struct reiserfs_de_head *)body;
	278
	279	/* direntry header of "." */
	280	put_deh_offset(&(deh[0]), DOT_OFFSET);
	281	/* these two are from make_le_item_head, and are are LE */
	282	deh[0].deh_dir_id = dirid;
	283	deh[0].deh_objectid = objid;
	284	deh[0].deh_state = 0; /* Endian safe if 0 */
	285	put_deh_location(&(deh[0]), EMPTY_DIR_SIZE - ROUND_UP(strlen(".")));
	286	mark_de_visible(&(deh[0]));
	287
	288	/* direntry header of ".." */
	289	put_deh_offset(&(deh[1]), DOT_DOT_OFFSET);
	290	/* key of ".." for the root directory */
	291	/* these two are from the inode, and are are LE */
	292	deh[1].deh_dir_id = par_dirid;
	293	deh[1].deh_objectid = par_objid;
	294	deh[1].deh_state = 0; /* Endian safe if 0 */
	295	put_deh_location(&(deh[1]),
	296	deh_location(&(deh[0])) - ROUND_UP(strlen("..")));
	297	mark_de_visible(&(deh[1]));
	298
	299	/* copy ".." and "." */
	300	memcpy(body + deh_location(&(deh[0])), ".", 1);
	301	memcpy(body + deh_location(&(deh[1])), "..", 2);
1da177e4	302	}