[linux.git] / fs / ext2 / namei.c

// SPDX-License-Identifier: GPL-2.0
/*
 * linux/fs/ext2/namei.c
 *
 * Rewrite to pagecache. Almost all code had been changed, so blame me
 * if the things go wrong. Please, send bug reports to
 * [email protected]
 *
 * Stuff here is basically a glue between the VFS and generic UNIXish
 * filesystem that keeps everything in pagecache. All knowledge of the
 * directory layout is in fs/ext2/dir.c - it turned out to be easily separatable
 * and it's easier to debug that way. In principle we might want to
 * generalize that a bit and turn it into a library. Or not.
 *
 * The only non-static object here is ext2_dir_inode_operations.
 *
 * TODO: get rid of kmap() use, add readahead.
 *
 * Copyright (C) 1992, 1993, 1994, 1995
 * Remy Card ([email protected])
 * Laboratoire MASI - Institut Blaise Pascal
 * Universite Pierre et Marie Curie (Paris VI)
 *
 *  from
 *
 *  linux/fs/minix/namei.c
 *
 *  Copyright (C) 1991, 1992  Linus Torvalds
 *
 *  Big-endian to little-endian byte-swapping/bitmaps by
 *        David S. Miller ([email protected]), 1995
 */

#include <linux/pagemap.h>
#include <linux/quotaops.h>
#include "ext2.h"
#include "xattr.h"
#include "acl.h"

static inline int ext2_add_nondir(struct dentry *dentry, struct inode *inode)
{
	int err = ext2_add_link(dentry, inode);
	if (!err) {
		d_instantiate_new(dentry, inode);
		return 0;
	}
	inode_dec_link_count(inode);
	discard_new_inode(inode);
	return err;
}

/*
 * Methods themselves.
 */

static struct dentry *ext2_lookup(struct inode * dir, struct dentry *dentry, unsigned int flags)
{
	struct inode * inode;
	ino_t ino;
	
	if (dentry->d_name.len > EXT2_NAME_LEN)
		return ERR_PTR(-ENAMETOOLONG);

	ino = ext2_inode_by_name(dir, &dentry->d_name);
	inode = NULL;
	if (ino) {
		inode = ext2_iget(dir->i_sb, ino);
		if (inode == ERR_PTR(-ESTALE)) {
			ext2_error(dir->i_sb, __func__,
					"deleted inode referenced: %lu",
					(unsigned long) ino);
			return ERR_PTR(-EIO);
		}
	}
	return d_splice_alias(inode, dentry);
}

struct dentry *ext2_get_parent(struct dentry *child)
{
	struct qstr dotdot = QSTR_INIT("..", 2);
	unsigned long ino = ext2_inode_by_name(d_inode(child), &dotdot);
	if (!ino)
		return ERR_PTR(-ENOENT);
	return d_obtain_alias(ext2_iget(child->d_sb, ino));
} 

/*
 * By the time this is called, we already have created
 * the directory cache entry for the new file, but it
 * is so far negative - it has no inode.
 *
 * If the create succeeds, we fill in the inode information
 * with d_instantiate(). 
 */
static int ext2_create (struct inode * dir, struct dentry * dentry, umode_t mode, bool excl)
{
	struct inode *inode;
	int err;

	err = dquot_initialize(dir);
	if (err)
		return err;

	inode = ext2_new_inode(dir, mode, &dentry->d_name);
	if (IS_ERR(inode))
		return PTR_ERR(inode);

	ext2_set_file_ops(inode);
	mark_inode_dirty(inode);
	return ext2_add_nondir(dentry, inode);
}

static int ext2_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode)
{
	struct inode *inode = ext2_new_inode(dir, mode, NULL);
	if (IS_ERR(inode))
		return PTR_ERR(inode);

	ext2_set_file_ops(inode);
	mark_inode_dirty(inode);
	d_tmpfile(dentry, inode);
	unlock_new_inode(inode);
	return 0;
}

static int ext2_mknod (struct inode * dir, struct dentry *dentry, umode_t mode, dev_t rdev)
{
	struct inode * inode;
	int err;

	err = dquot_initialize(dir);
	if (err)
		return err;

	inode = ext2_new_inode (dir, mode, &dentry->d_name);
	err = PTR_ERR(inode);
	if (!IS_ERR(inode)) {
		init_special_inode(inode, inode->i_mode, rdev);
#ifdef CONFIG_EXT2_FS_XATTR
		inode->i_op = &ext2_special_inode_operations;
#endif
		mark_inode_dirty(inode);
		err = ext2_add_nondir(dentry, inode);
	}
	return err;
}

static int ext2_symlink (struct inode * dir, struct dentry * dentry,
	const char * symname)
{
	struct super_block * sb = dir->i_sb;
	int err = -ENAMETOOLONG;
	unsigned l = strlen(symname)+1;
	struct inode * inode;

	if (l > sb->s_blocksize)
		goto out;

	err = dquot_initialize(dir);
	if (err)
		goto out;

	inode = ext2_new_inode (dir, S_IFLNK | S_IRWXUGO, &dentry->d_name);
	err = PTR_ERR(inode);
	if (IS_ERR(inode))
		goto out;

	if (l > sizeof (EXT2_I(inode)->i_data)) {
		/* slow symlink */
		inode->i_op = &ext2_symlink_inode_operations;
		inode_nohighmem(inode);
		if (test_opt(inode->i_sb, NOBH))
			inode->i_mapping->a_ops = &ext2_nobh_aops;
		else
			inode->i_mapping->a_ops = &ext2_aops;
		err = page_symlink(inode, symname, l);
		if (err)
			goto out_fail;
	} else {
		/* fast symlink */
		inode->i_op = &ext2_fast_symlink_inode_operations;
		inode->i_link = (char*)EXT2_I(inode)->i_data;
		memcpy(inode->i_link, symname, l);
		inode->i_size = l-1;
	}
	mark_inode_dirty(inode);

	err = ext2_add_nondir(dentry, inode);
out:
	return err;

out_fail:
	inode_dec_link_count(inode);
	discard_new_inode(inode);
	goto out;
}

static int ext2_link (struct dentry * old_dentry, struct inode * dir,
	struct dentry *dentry)
{
	struct inode *inode = d_inode(old_dentry);
	int err;

	err = dquot_initialize(dir);
	if (err)
		return err;

	inode->i_ctime = current_time(inode);
	inode_inc_link_count(inode);
	ihold(inode);

	err = ext2_add_link(dentry, inode);
	if (!err) {
		d_instantiate(dentry, inode);
		return 0;
	}
	inode_dec_link_count(inode);
	iput(inode);
	return err;
}

static int ext2_mkdir(struct inode * dir, struct dentry * dentry, umode_t mode)
{
	struct inode * inode;
	int err;

	err = dquot_initialize(dir);
	if (err)
		return err;

	inode_inc_link_count(dir);

	inode = ext2_new_inode(dir, S_IFDIR | mode, &dentry->d_name);
	err = PTR_ERR(inode);
	if (IS_ERR(inode))
		goto out_dir;

	inode->i_op = &ext2_dir_inode_operations;
	inode->i_fop = &ext2_dir_operations;
	if (test_opt(inode->i_sb, NOBH))
		inode->i_mapping->a_ops = &ext2_nobh_aops;
	else
		inode->i_mapping->a_ops = &ext2_aops;

	inode_inc_link_count(inode);

	err = ext2_make_empty(inode, dir);
	if (err)
		goto out_fail;

	err = ext2_add_link(dentry, inode);
	if (err)
		goto out_fail;

	d_instantiate_new(dentry, inode);
out:
	return err;

out_fail:
	inode_dec_link_count(inode);
	inode_dec_link_count(inode);
	discard_new_inode(inode);
out_dir:
	inode_dec_link_count(dir);
	goto out;
}

static int ext2_unlink(struct inode * dir, struct dentry *dentry)
{
	struct inode * inode = d_inode(dentry);
	struct ext2_dir_entry_2 * de;
	struct page * page;
	int err;

	err = dquot_initialize(dir);
	if (err)
		goto out;

	de = ext2_find_entry (dir, &dentry->d_name, &page);
	if (!de) {
		err = -ENOENT;
		goto out;
	}

	err = ext2_delete_entry (de, page);
	if (err)
		goto out;

	inode->i_ctime = dir->i_ctime;
	inode_dec_link_count(inode);
	err = 0;
out:
	return err;
}

static int ext2_rmdir (struct inode * dir, struct dentry *dentry)
{
	struct inode * inode = d_inode(dentry);
	int err = -ENOTEMPTY;

	if (ext2_empty_dir(inode)) {
		err = ext2_unlink(dir, dentry);
		if (!err) {
			inode->i_size = 0;
			inode_dec_link_count(inode);
			inode_dec_link_count(dir);
		}
	}
	return err;
}

static int ext2_rename (struct inode * old_dir, struct dentry * old_dentry,
			struct inode * new_dir,	struct dentry * new_dentry,
			unsigned int flags)
{
	struct inode * old_inode = d_inode(old_dentry);
	struct inode * new_inode = d_inode(new_dentry);
	struct page * dir_page = NULL;
	struct ext2_dir_entry_2 * dir_de = NULL;
	struct page * old_page;
	struct ext2_dir_entry_2 * old_de;
	int err;

	if (flags & ~RENAME_NOREPLACE)
		return -EINVAL;

	err = dquot_initialize(old_dir);
	if (err)
		goto out;

	err = dquot_initialize(new_dir);
	if (err)
		goto out;

	old_de = ext2_find_entry (old_dir, &old_dentry->d_name, &old_page);
	if (!old_de) {
		err = -ENOENT;
		goto out;
	}

	if (S_ISDIR(old_inode->i_mode)) {
		err = -EIO;
		dir_de = ext2_dotdot(old_inode, &dir_page);
		if (!dir_de)
			goto out_old;
	}

	if (new_inode) {
		struct page *new_page;
		struct ext2_dir_entry_2 *new_de;

		err = -ENOTEMPTY;
		if (dir_de && !ext2_empty_dir (new_inode))
			goto out_dir;

		err = -ENOENT;
		new_de = ext2_find_entry (new_dir, &new_dentry->d_name, &new_page);
		if (!new_de)
			goto out_dir;
		ext2_set_link(new_dir, new_de, new_page, old_inode, 1);
		new_inode->i_ctime = current_time(new_inode);
		if (dir_de)
			drop_nlink(new_inode);
		inode_dec_link_count(new_inode);
	} else {
		err = ext2_add_link(new_dentry, old_inode);
		if (err)
			goto out_dir;
		if (dir_de)
			inode_inc_link_count(new_dir);
	}

	/*
	 * Like most other Unix systems, set the ctime for inodes on a
 	 * rename.
	 */
	old_inode->i_ctime = current_time(old_inode);
	mark_inode_dirty(old_inode);

	ext2_delete_entry (old_de, old_page);

	if (dir_de) {
		if (old_dir != new_dir)
			ext2_set_link(old_inode, dir_de, dir_page, new_dir, 0);
		else {
			kunmap(dir_page);
			put_page(dir_page);
		}
		inode_dec_link_count(old_dir);
	}
	return 0;


out_dir:
	if (dir_de) {
		kunmap(dir_page);
		put_page(dir_page);
	}
out_old:
	kunmap(old_page);
	put_page(old_page);
out:
	return err;
}

const struct inode_operations ext2_dir_inode_operations = {
	.create		= ext2_create,
	.lookup		= ext2_lookup,
	.link		= ext2_link,
	.unlink		= ext2_unlink,
	.symlink	= ext2_symlink,
	.mkdir		= ext2_mkdir,
	.rmdir		= ext2_rmdir,
	.mknod		= ext2_mknod,
	.rename		= ext2_rename,
#ifdef CONFIG_EXT2_FS_XATTR
	.listxattr	= ext2_listxattr,
#endif
	.setattr	= ext2_setattr,
	.get_acl	= ext2_get_acl,
	.set_acl	= ext2_set_acl,
	.tmpfile	= ext2_tmpfile,
};

const struct inode_operations ext2_special_inode_operations = {
#ifdef CONFIG_EXT2_FS_XATTR
	.listxattr	= ext2_listxattr,
#endif
	.setattr	= ext2_setattr,
	.get_acl	= ext2_get_acl,
	.set_acl	= ext2_set_acl,
};
Commit	Line	Data
b2441318	1	// SPDX-License-Identifier: GPL-2.0
1da177e4 LT	2	/*
	3	* linux/fs/ext2/namei.c
	4	*
	5	* Rewrite to pagecache. Almost all code had been changed, so blame me
	6	* if the things go wrong. Please, send bug reports to
	7	* [email protected]
	8	*
	9	* Stuff here is basically a glue between the VFS and generic UNIXish
	10	* filesystem that keeps everything in pagecache. All knowledge of the
	11	* directory layout is in fs/ext2/dir.c - it turned out to be easily separatable
	12	* and it's easier to debug that way. In principle we might want to
	13	* generalize that a bit and turn it into a library. Or not.
	14	*
	15	* The only non-static object here is ext2_dir_inode_operations.
	16	*
	17	* TODO: get rid of kmap() use, add readahead.
	18	*
	19	* Copyright (C) 1992, 1993, 1994, 1995
	20	* Remy Card ([email protected])
	21	* Laboratoire MASI - Institut Blaise Pascal
	22	* Universite Pierre et Marie Curie (Paris VI)
	23	*
	24	* from
	25	*
	26	* linux/fs/minix/namei.c
	27	*
	28	* Copyright (C) 1991, 1992 Linus Torvalds
	29	*
	30	* Big-endian to little-endian byte-swapping/bitmaps by
	31	* David S. Miller ([email protected]), 1995
	32	*/
	33
	34	#include <linux/pagemap.h>
907f4554	35	#include <linux/quotaops.h>
1da177e4 LT	36	#include "ext2.h"
	37	#include "xattr.h"
	38	#include "acl.h"
	39
1da177e4 LT	40	static inline int ext2_add_nondir(struct dentry dentry, struct inode inode)
	41	{
	42	int err = ext2_add_link(dentry, inode);
	43	if (!err) {
1e2e547a	44	d_instantiate_new(dentry, inode);
1da177e4 LT	45	return 0;
1da177e4 LT	46	}
a513b035	47	inode_dec_link_count(inode);
2e5afe54	48	discard_new_inode(inode);
1da177e4 LT	49	return err;
	50	}
	51
	52	/*
	53	* Methods themselves.
	54	*/
	55
00cd8dd3	56	static struct dentry ext2_lookup(struct inode dir, struct dentry *dentry, unsigned int flags)
1da177e4 LT	57	{
	58	struct inode * inode;
	59	ino_t ino;
	60
	61	if (dentry->d_name.len > EXT2_NAME_LEN)
	62	return ERR_PTR(-ENAMETOOLONG);
	63
a9885444	64	ino = ext2_inode_by_name(dir, &dentry->d_name);
1da177e4 LT	65	inode = NULL;
1da177e4 LT	66	if (ino) {
52fcf703	67	inode = ext2_iget(dir->i_sb, ino);
a9049376 AV	68	if (inode == ERR_PTR(-ESTALE)) {
	69	ext2_error(dir->i_sb, __func__,
	70	"deleted inode referenced: %lu",
	71	(unsigned long) ino);
	72	return ERR_PTR(-EIO);
4d6c13f8	73	}
1da177e4	74	}
082a05c6	75	return d_splice_alias(inode, dentry);
1da177e4 LT	76	}
	77
	78	struct dentry ext2_get_parent(struct dentry child)
	79	{
26fe5750	80	struct qstr dotdot = QSTR_INIT("..", 2);
2b0143b5	81	unsigned long ino = ext2_inode_by_name(d_inode(child), &dotdot);
1da177e4 LT	82	if (!ino)
1da177e4 LT	83	return ERR_PTR(-ENOENT);
fc64005c	84	return d_obtain_alias(ext2_iget(child->d_sb, ino));
1da177e4 LT	85	}
	86
	87	/*
	88	* By the time this is called, we already have created
	89	* the directory cache entry for the new file, but it
	90	* is so far negative - it has no inode.
	91	*
	92	* If the create succeeds, we fill in the inode information
	93	* with d_instantiate().
	94	*/
ebfc3b49	95	static int ext2_create (struct inode * dir, struct dentry * dentry, umode_t mode, bool excl)
1da177e4	96	{
907f4554	97	struct inode *inode;
c2edb305	98	int err;
907f4554	99
c2edb305 JK	100	err = dquot_initialize(dir);
	101	if (err)
	102	return err;
907f4554	103
2a7dba39	104	inode = ext2_new_inode(dir, mode, &dentry->d_name);
907f4554 CH	105	if (IS_ERR(inode))
	106	return PTR_ERR(inode);
	107
fb094c90	108	ext2_set_file_ops(inode);
907f4554 CH	109	mark_inode_dirty(inode);
907f4554 CH	110	return ext2_add_nondir(dentry, inode);
1da177e4 LT	111	}
1da177e4 LT	112
60545d0d AV	113	static int ext2_tmpfile(struct inode dir, struct dentry dentry, umode_t mode)
	114	{
	115	struct inode *inode = ext2_new_inode(dir, mode, NULL);
	116	if (IS_ERR(inode))
	117	return PTR_ERR(inode);
	118
fb094c90	119	ext2_set_file_ops(inode);
60545d0d AV	120	mark_inode_dirty(inode);
	121	d_tmpfile(dentry, inode);
	122	unlock_new_inode(inode);
	123	return 0;
	124	}
	125
1a67aafb	126	static int ext2_mknod (struct inode * dir, struct dentry *dentry, umode_t mode, dev_t rdev)
1da177e4 LT	127	{
	128	struct inode * inode;
	129	int err;
	130
c2edb305 JK	131	err = dquot_initialize(dir);
	132	if (err)
	133	return err;
907f4554	134
2a7dba39	135	inode = ext2_new_inode (dir, mode, &dentry->d_name);
1da177e4 LT	136	err = PTR_ERR(inode);
	137	if (!IS_ERR(inode)) {
	138	init_special_inode(inode, inode->i_mode, rdev);
	139	#ifdef CONFIG_EXT2_FS_XATTR
	140	inode->i_op = &ext2_special_inode_operations;
	141	#endif
	142	mark_inode_dirty(inode);
	143	err = ext2_add_nondir(dentry, inode);
	144	}
	145	return err;
	146	}
	147
	148	static int ext2_symlink (struct inode * dir, struct dentry * dentry,
	149	const char * symname)
	150	{
	151	struct super_block * sb = dir->i_sb;
	152	int err = -ENAMETOOLONG;
	153	unsigned l = strlen(symname)+1;
	154	struct inode * inode;
	155
	156	if (l > sb->s_blocksize)
	157	goto out;
	158
c2edb305 JK	159	err = dquot_initialize(dir);
	160	if (err)
	161	goto out;
907f4554	162
2a7dba39	163	inode = ext2_new_inode (dir, S_IFLNK \| S_IRWXUGO, &dentry->d_name);
1da177e4 LT	164	err = PTR_ERR(inode);
	165	if (IS_ERR(inode))
	166	goto out;
	167
	168	if (l > sizeof (EXT2_I(inode)->i_data)) {
	169	/* slow symlink */
	170	inode->i_op = &ext2_symlink_inode_operations;
21fc61c7	171	inode_nohighmem(inode);
1da177e4 LT	172	if (test_opt(inode->i_sb, NOBH))
	173	inode->i_mapping->a_ops = &ext2_nobh_aops;
	174	else
	175	inode->i_mapping->a_ops = &ext2_aops;
	176	err = page_symlink(inode, symname, l);
	177	if (err)
	178	goto out_fail;
	179	} else {
	180	/* fast symlink */
	181	inode->i_op = &ext2_fast_symlink_inode_operations;
cbe0fa38 AV	182	inode->i_link = (char*)EXT2_I(inode)->i_data;
cbe0fa38 AV	183	memcpy(inode->i_link, symname, l);
1da177e4 LT	184	inode->i_size = l-1;
	185	}
	186	mark_inode_dirty(inode);
	187
	188	err = ext2_add_nondir(dentry, inode);
	189	out:
	190	return err;
	191
	192	out_fail:
a513b035	193	inode_dec_link_count(inode);
2e5afe54	194	discard_new_inode(inode);
1da177e4 LT	195	goto out;
	196	}
	197
	198	static int ext2_link (struct dentry * old_dentry, struct inode * dir,
	199	struct dentry *dentry)
	200	{
2b0143b5	201	struct inode *inode = d_inode(old_dentry);
41080b5a	202	int err;
1da177e4	203
c2edb305 JK	204	err = dquot_initialize(dir);
	205	if (err)
	206	return err;
907f4554	207
02027d42	208	inode->i_ctime = current_time(inode);
a513b035	209	inode_inc_link_count(inode);
7de9c6ee	210	ihold(inode);
1da177e4	211
41080b5a AV	212	err = ext2_add_link(dentry, inode);
	213	if (!err) {
	214	d_instantiate(dentry, inode);
	215	return 0;
	216	}
	217	inode_dec_link_count(inode);
	218	iput(inode);
	219	return err;
1da177e4 LT	220	}
1da177e4 LT	221
18bb1db3	222	static int ext2_mkdir(struct inode * dir, struct dentry * dentry, umode_t mode)
1da177e4 LT	223	{
1da177e4 LT	224	struct inode * inode;
8de52778	225	int err;
1da177e4	226
c2edb305 JK	227	err = dquot_initialize(dir);
	228	if (err)
	229	return err;
907f4554	230
a513b035	231	inode_inc_link_count(dir);
1da177e4	232
2a7dba39	233	inode = ext2_new_inode(dir, S_IFDIR \| mode, &dentry->d_name);
1da177e4 LT	234	err = PTR_ERR(inode);
	235	if (IS_ERR(inode))
	236	goto out_dir;
	237
	238	inode->i_op = &ext2_dir_inode_operations;
	239	inode->i_fop = &ext2_dir_operations;
	240	if (test_opt(inode->i_sb, NOBH))
	241	inode->i_mapping->a_ops = &ext2_nobh_aops;
	242	else
	243	inode->i_mapping->a_ops = &ext2_aops;
	244
a513b035	245	inode_inc_link_count(inode);
1da177e4 LT	246
	247	err = ext2_make_empty(inode, dir);
	248	if (err)
	249	goto out_fail;
	250
	251	err = ext2_add_link(dentry, inode);
	252	if (err)
	253	goto out_fail;
	254
1e2e547a	255	d_instantiate_new(dentry, inode);
1da177e4 LT	256	out:
	257	return err;
	258
	259	out_fail:
a513b035 AD	260	inode_dec_link_count(inode);
a513b035 AD	261	inode_dec_link_count(inode);
2e5afe54	262	discard_new_inode(inode);
1da177e4	263	out_dir:
a513b035	264	inode_dec_link_count(dir);
1da177e4 LT	265	goto out;
	266	}
	267
	268	static int ext2_unlink(struct inode * dir, struct dentry *dentry)
	269	{
2b0143b5	270	struct inode * inode = d_inode(dentry);
1da177e4 LT	271	struct ext2_dir_entry_2 * de;
1da177e4 LT	272	struct page * page;
c2edb305	273	int err;
1da177e4	274
c2edb305 JK	275	err = dquot_initialize(dir);
	276	if (err)
	277	goto out;
907f4554	278
a9885444	279	de = ext2_find_entry (dir, &dentry->d_name, &page);
c2edb305 JK	280	if (!de) {
c2edb305 JK	281	err = -ENOENT;
1da177e4	282	goto out;
c2edb305	283	}
1da177e4 LT	284
	285	err = ext2_delete_entry (de, page);
	286	if (err)
	287	goto out;
	288
	289	inode->i_ctime = dir->i_ctime;
a513b035	290	inode_dec_link_count(inode);
1da177e4 LT	291	err = 0;
	292	out:
	293	return err;
	294	}
	295
	296	static int ext2_rmdir (struct inode * dir, struct dentry *dentry)
	297	{
2b0143b5	298	struct inode * inode = d_inode(dentry);
1da177e4 LT	299	int err = -ENOTEMPTY;
	300
	301	if (ext2_empty_dir(inode)) {
	302	err = ext2_unlink(dir, dentry);
	303	if (!err) {
	304	inode->i_size = 0;
a513b035 AD	305	inode_dec_link_count(inode);
a513b035 AD	306	inode_dec_link_count(dir);
1da177e4 LT	307	}
	308	}
	309	return err;
	310	}
	311
	312	static int ext2_rename (struct inode * old_dir, struct dentry * old_dentry,
f03b8ad8 MS	313	struct inode * new_dir, struct dentry * new_dentry,
f03b8ad8 MS	314	unsigned int flags)
1da177e4	315	{
2b0143b5 DH	316	struct inode * old_inode = d_inode(old_dentry);
2b0143b5 DH	317	struct inode * new_inode = d_inode(new_dentry);
1da177e4 LT	318	struct page * dir_page = NULL;
	319	struct ext2_dir_entry_2 * dir_de = NULL;
	320	struct page * old_page;
	321	struct ext2_dir_entry_2 * old_de;
c2edb305	322	int err;
1da177e4	323
f03b8ad8 MS	324	if (flags & ~RENAME_NOREPLACE)
	325	return -EINVAL;
	326
c2edb305 JK	327	err = dquot_initialize(old_dir);
	328	if (err)
	329	goto out;
	330
	331	err = dquot_initialize(new_dir);
	332	if (err)
	333	goto out;
907f4554	334
a9885444	335	old_de = ext2_find_entry (old_dir, &old_dentry->d_name, &old_page);
c2edb305 JK	336	if (!old_de) {
c2edb305 JK	337	err = -ENOENT;
1da177e4	338	goto out;
c2edb305	339	}
1da177e4 LT	340
	341	if (S_ISDIR(old_inode->i_mode)) {
	342	err = -EIO;
	343	dir_de = ext2_dotdot(old_inode, &dir_page);
	344	if (!dir_de)
	345	goto out_old;
	346	}
	347
	348	if (new_inode) {
	349	struct page *new_page;
	350	struct ext2_dir_entry_2 *new_de;
	351
	352	err = -ENOTEMPTY;
	353	if (dir_de && !ext2_empty_dir (new_inode))
	354	goto out_dir;
	355
	356	err = -ENOENT;
a9885444	357	new_de = ext2_find_entry (new_dir, &new_dentry->d_name, &new_page);
1da177e4 LT	358	if (!new_de)
1da177e4 LT	359	goto out_dir;
39fe7557	360	ext2_set_link(new_dir, new_de, new_page, old_inode, 1);
02027d42	361	new_inode->i_ctime = current_time(new_inode);
1da177e4	362	if (dir_de)
9a53c3a7	363	drop_nlink(new_inode);
a513b035	364	inode_dec_link_count(new_inode);
1da177e4	365	} else {
1da177e4	366	err = ext2_add_link(new_dentry, old_inode);
e8a80c6f	367	if (err)
1da177e4	368	goto out_dir;
1da177e4	369	if (dir_de)
a513b035	370	inode_inc_link_count(new_dir);
1da177e4 LT	371	}
	372
	373	/*
	374	* Like most other Unix systems, set the ctime for inodes on a
	375	* rename.
1da177e4	376	*/
02027d42	377	old_inode->i_ctime = current_time(old_inode);
e8a80c6f	378	mark_inode_dirty(old_inode);
1da177e4 LT	379
1da177e4 LT	380	ext2_delete_entry (old_de, old_page);
1da177e4 LT	381
1da177e4 LT	382	if (dir_de) {
39fe7557 JK	383	if (old_dir != new_dir)
39fe7557 JK	384	ext2_set_link(old_inode, dir_de, dir_page, new_dir, 0);
9de6886e NP	385	else {
9de6886e NP	386	kunmap(dir_page);
09cbfeaf	387	put_page(dir_page);
9de6886e	388	}
a513b035	389	inode_dec_link_count(old_dir);
1da177e4 LT	390	}
	391	return 0;
	392
	393
	394	out_dir:
	395	if (dir_de) {
	396	kunmap(dir_page);
09cbfeaf	397	put_page(dir_page);
1da177e4 LT	398	}
	399	out_old:
	400	kunmap(old_page);
09cbfeaf	401	put_page(old_page);
1da177e4 LT	402	out:
	403	return err;
	404	}
	405
754661f1	406	const struct inode_operations ext2_dir_inode_operations = {
1da177e4 LT	407	.create = ext2_create,
	408	.lookup = ext2_lookup,
	409	.link = ext2_link,
	410	.unlink = ext2_unlink,
	411	.symlink = ext2_symlink,
	412	.mkdir = ext2_mkdir,
	413	.rmdir = ext2_rmdir,
	414	.mknod = ext2_mknod,
	415	.rename = ext2_rename,
	416	#ifdef CONFIG_EXT2_FS_XATTR
1da177e4	417	.listxattr = ext2_listxattr,
1da177e4 LT	418	#endif
1da177e4 LT	419	.setattr = ext2_setattr,
4e34e719	420	.get_acl = ext2_get_acl,
64e178a7	421	.set_acl = ext2_set_acl,
60545d0d	422	.tmpfile = ext2_tmpfile,
1da177e4 LT	423	};
1da177e4 LT	424
754661f1	425	const struct inode_operations ext2_special_inode_operations = {
1da177e4	426	#ifdef CONFIG_EXT2_FS_XATTR
1da177e4	427	.listxattr = ext2_listxattr,
1da177e4 LT	428	#endif
1da177e4 LT	429	.setattr = ext2_setattr,
4e34e719	430	.get_acl = ext2_get_acl,
64e178a7	431	.set_acl = ext2_set_acl,
1da177e4	432	};