[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 = 0;
	int res;
	
	if (dentry->d_name.len > EXT2_NAME_LEN)
		return ERR_PTR(-ENAMETOOLONG);

	res = ext2_inode_by_name(dir, &dentry->d_name, &ino);
	if (res)
		return ERR_PTR(res);
	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);
	ino_t ino = 0;
	int res;

	res = ext2_inode_by_name(d_inode(child), &dotdot, &ino);
	if (res)
		return ERR_PTR(res);
	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);
		inode->i_op = &ext2_special_inode_operations;
		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 (IS_ERR(de)) {
		err = PTR_ERR(de);
		goto out;
	}
	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 (IS_ERR(old_de)) {
		err = PTR_ERR(old_de);
		goto out;
	}
	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 (IS_ERR(new_de)) {
			err = PTR_ERR(new_de);
			goto out_dir;
		}
		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,
	.listxattr	= ext2_listxattr,
	.getattr	= ext2_getattr,
	.setattr	= ext2_setattr,
	.get_acl	= ext2_get_acl,
	.set_acl	= ext2_set_acl,
	.tmpfile	= ext2_tmpfile,
};

const struct inode_operations ext2_special_inode_operations = {
	.listxattr	= ext2_listxattr,
	.getattr	= ext2_getattr,
	.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	{
1da177e4 LT	58	struct inode * inode;
b4962091	59	ino_t ino = 0;
b4962091	60	int res;
1da177e4 LT	61
	62	if (dentry->d_name.len > EXT2_NAME_LEN)
	63	return ERR_PTR(-ENAMETOOLONG);
	64
b4962091	65	res = ext2_inode_by_name(dir, &dentry->d_name, &ino);
	66	if (res)
	67	return ERR_PTR(res);
1da177e4 LT	68	inode = NULL;
1da177e4 LT	69	if (ino) {
52fcf703	70	inode = ext2_iget(dir->i_sb, ino);
a9049376 AV	71	if (inode == ERR_PTR(-ESTALE)) {
	72	ext2_error(dir->i_sb, __func__,
	73	"deleted inode referenced: %lu",
	74	(unsigned long) ino);
	75	return ERR_PTR(-EIO);
4d6c13f8	76	}
1da177e4	77	}
082a05c6	78	return d_splice_alias(inode, dentry);
1da177e4 LT	79	}
	80
	81	struct dentry ext2_get_parent(struct dentry child)
	82	{
26fe5750	83	struct qstr dotdot = QSTR_INIT("..", 2);
b4962091	84	ino_t ino = 0;
	85	int res;
	86
	87	res = ext2_inode_by_name(d_inode(child), &dotdot, &ino);
	88	if (res)
	89	return ERR_PTR(res);
1da177e4 LT	90	if (!ino)
1da177e4 LT	91	return ERR_PTR(-ENOENT);
fc64005c	92	return d_obtain_alias(ext2_iget(child->d_sb, ino));
1da177e4 LT	93	}
	94
	95	/*
	96	* By the time this is called, we already have created
	97	* the directory cache entry for the new file, but it
	98	* is so far negative - it has no inode.
	99	*
	100	* If the create succeeds, we fill in the inode information
	101	* with d_instantiate().
	102	*/
ebfc3b49	103	static int ext2_create (struct inode * dir, struct dentry * dentry, umode_t mode, bool excl)
1da177e4	104	{
907f4554	105	struct inode *inode;
c2edb305	106	int err;
907f4554	107
c2edb305 JK	108	err = dquot_initialize(dir);
	109	if (err)
	110	return err;
907f4554	111
2a7dba39	112	inode = ext2_new_inode(dir, mode, &dentry->d_name);
907f4554 CH	113	if (IS_ERR(inode))
	114	return PTR_ERR(inode);
	115
fb094c90	116	ext2_set_file_ops(inode);
907f4554 CH	117	mark_inode_dirty(inode);
907f4554 CH	118	return ext2_add_nondir(dentry, inode);
1da177e4 LT	119	}
1da177e4 LT	120
60545d0d AV	121	static int ext2_tmpfile(struct inode dir, struct dentry dentry, umode_t mode)
	122	{
	123	struct inode *inode = ext2_new_inode(dir, mode, NULL);
	124	if (IS_ERR(inode))
	125	return PTR_ERR(inode);
	126
fb094c90	127	ext2_set_file_ops(inode);
60545d0d AV	128	mark_inode_dirty(inode);
	129	d_tmpfile(dentry, inode);
	130	unlock_new_inode(inode);
	131	return 0;
	132	}
	133
1a67aafb	134	static int ext2_mknod (struct inode * dir, struct dentry *dentry, umode_t mode, dev_t rdev)
1da177e4 LT	135	{
	136	struct inode * inode;
	137	int err;
	138
c2edb305 JK	139	err = dquot_initialize(dir);
	140	if (err)
	141	return err;
907f4554	142
2a7dba39	143	inode = ext2_new_inode (dir, mode, &dentry->d_name);
1da177e4 LT	144	err = PTR_ERR(inode);
	145	if (!IS_ERR(inode)) {
	146	init_special_inode(inode, inode->i_mode, rdev);
1da177e4	147	inode->i_op = &ext2_special_inode_operations;
1da177e4 LT	148	mark_inode_dirty(inode);
	149	err = ext2_add_nondir(dentry, inode);
	150	}
	151	return err;
	152	}
	153
	154	static int ext2_symlink (struct inode * dir, struct dentry * dentry,
	155	const char * symname)
	156	{
	157	struct super_block * sb = dir->i_sb;
	158	int err = -ENAMETOOLONG;
	159	unsigned l = strlen(symname)+1;
	160	struct inode * inode;
	161
	162	if (l > sb->s_blocksize)
	163	goto out;
	164
c2edb305 JK	165	err = dquot_initialize(dir);
	166	if (err)
	167	goto out;
907f4554	168
2a7dba39	169	inode = ext2_new_inode (dir, S_IFLNK \| S_IRWXUGO, &dentry->d_name);
1da177e4 LT	170	err = PTR_ERR(inode);
	171	if (IS_ERR(inode))
	172	goto out;
	173
	174	if (l > sizeof (EXT2_I(inode)->i_data)) {
	175	/* slow symlink */
	176	inode->i_op = &ext2_symlink_inode_operations;
21fc61c7	177	inode_nohighmem(inode);
1da177e4 LT	178	if (test_opt(inode->i_sb, NOBH))
	179	inode->i_mapping->a_ops = &ext2_nobh_aops;
	180	else
	181	inode->i_mapping->a_ops = &ext2_aops;
	182	err = page_symlink(inode, symname, l);
	183	if (err)
	184	goto out_fail;
	185	} else {
	186	/* fast symlink */
	187	inode->i_op = &ext2_fast_symlink_inode_operations;
cbe0fa38 AV	188	inode->i_link = (char*)EXT2_I(inode)->i_data;
cbe0fa38 AV	189	memcpy(inode->i_link, symname, l);
1da177e4 LT	190	inode->i_size = l-1;
	191	}
	192	mark_inode_dirty(inode);
	193
	194	err = ext2_add_nondir(dentry, inode);
	195	out:
	196	return err;
	197
	198	out_fail:
a513b035	199	inode_dec_link_count(inode);
2e5afe54	200	discard_new_inode(inode);
1da177e4 LT	201	goto out;
	202	}
	203
	204	static int ext2_link (struct dentry * old_dentry, struct inode * dir,
	205	struct dentry *dentry)
	206	{
2b0143b5	207	struct inode *inode = d_inode(old_dentry);
41080b5a	208	int err;
1da177e4	209
c2edb305 JK	210	err = dquot_initialize(dir);
	211	if (err)
	212	return err;
907f4554	213
02027d42	214	inode->i_ctime = current_time(inode);
a513b035	215	inode_inc_link_count(inode);
7de9c6ee	216	ihold(inode);
1da177e4	217
41080b5a AV	218	err = ext2_add_link(dentry, inode);
	219	if (!err) {
	220	d_instantiate(dentry, inode);
	221	return 0;
	222	}
	223	inode_dec_link_count(inode);
	224	iput(inode);
	225	return err;
1da177e4 LT	226	}
1da177e4 LT	227
18bb1db3	228	static int ext2_mkdir(struct inode * dir, struct dentry * dentry, umode_t mode)
1da177e4 LT	229	{
1da177e4 LT	230	struct inode * inode;
8de52778	231	int err;
1da177e4	232
c2edb305 JK	233	err = dquot_initialize(dir);
	234	if (err)
	235	return err;
907f4554	236
a513b035	237	inode_inc_link_count(dir);
1da177e4	238
2a7dba39	239	inode = ext2_new_inode(dir, S_IFDIR \| mode, &dentry->d_name);
1da177e4 LT	240	err = PTR_ERR(inode);
	241	if (IS_ERR(inode))
	242	goto out_dir;
	243
	244	inode->i_op = &ext2_dir_inode_operations;
	245	inode->i_fop = &ext2_dir_operations;
	246	if (test_opt(inode->i_sb, NOBH))
	247	inode->i_mapping->a_ops = &ext2_nobh_aops;
	248	else
	249	inode->i_mapping->a_ops = &ext2_aops;
	250
a513b035	251	inode_inc_link_count(inode);
1da177e4 LT	252
	253	err = ext2_make_empty(inode, dir);
	254	if (err)
	255	goto out_fail;
	256
	257	err = ext2_add_link(dentry, inode);
	258	if (err)
	259	goto out_fail;
	260
1e2e547a	261	d_instantiate_new(dentry, inode);
1da177e4 LT	262	out:
	263	return err;
	264
	265	out_fail:
a513b035 AD	266	inode_dec_link_count(inode);
a513b035 AD	267	inode_dec_link_count(inode);
2e5afe54	268	discard_new_inode(inode);
1da177e4	269	out_dir:
a513b035	270	inode_dec_link_count(dir);
1da177e4 LT	271	goto out;
	272	}
	273
	274	static int ext2_unlink(struct inode * dir, struct dentry *dentry)
	275	{
2b0143b5	276	struct inode * inode = d_inode(dentry);
1da177e4 LT	277	struct ext2_dir_entry_2 * de;
1da177e4 LT	278	struct page * page;
c2edb305	279	int err;
1da177e4	280
c2edb305 JK	281	err = dquot_initialize(dir);
	282	if (err)
	283	goto out;
907f4554	284
b4962091	285	de = ext2_find_entry(dir, &dentry->d_name, &page);
	286	if (IS_ERR(de)) {
	287	err = PTR_ERR(de);
	288	goto out;
	289	}
c2edb305 JK	290	if (!de) {
c2edb305 JK	291	err = -ENOENT;
1da177e4	292	goto out;
c2edb305	293	}
1da177e4 LT	294
	295	err = ext2_delete_entry (de, page);
	296	if (err)
	297	goto out;
	298
	299	inode->i_ctime = dir->i_ctime;
a513b035	300	inode_dec_link_count(inode);
1da177e4 LT	301	err = 0;
	302	out:
	303	return err;
	304	}
	305
	306	static int ext2_rmdir (struct inode * dir, struct dentry *dentry)
	307	{
2b0143b5	308	struct inode * inode = d_inode(dentry);
1da177e4 LT	309	int err = -ENOTEMPTY;
	310
	311	if (ext2_empty_dir(inode)) {
	312	err = ext2_unlink(dir, dentry);
	313	if (!err) {
	314	inode->i_size = 0;
a513b035 AD	315	inode_dec_link_count(inode);
a513b035 AD	316	inode_dec_link_count(dir);
1da177e4 LT	317	}
	318	}
	319	return err;
	320	}
	321
	322	static int ext2_rename (struct inode * old_dir, struct dentry * old_dentry,
f03b8ad8 MS	323	struct inode * new_dir, struct dentry * new_dentry,
f03b8ad8 MS	324	unsigned int flags)
1da177e4	325	{
2b0143b5 DH	326	struct inode * old_inode = d_inode(old_dentry);
2b0143b5 DH	327	struct inode * new_inode = d_inode(new_dentry);
1da177e4 LT	328	struct page * dir_page = NULL;
	329	struct ext2_dir_entry_2 * dir_de = NULL;
	330	struct page * old_page;
	331	struct ext2_dir_entry_2 * old_de;
c2edb305	332	int err;
1da177e4	333
f03b8ad8 MS	334	if (flags & ~RENAME_NOREPLACE)
	335	return -EINVAL;
	336
c2edb305 JK	337	err = dquot_initialize(old_dir);
	338	if (err)
	339	goto out;
	340
	341	err = dquot_initialize(new_dir);
	342	if (err)
	343	goto out;
907f4554	344
b4962091	345	old_de = ext2_find_entry(old_dir, &old_dentry->d_name, &old_page);
	346	if (IS_ERR(old_de)) {
	347	err = PTR_ERR(old_de);
	348	goto out;
	349	}
c2edb305 JK	350	if (!old_de) {
c2edb305 JK	351	err = -ENOENT;
1da177e4	352	goto out;
c2edb305	353	}
1da177e4 LT	354
	355	if (S_ISDIR(old_inode->i_mode)) {
	356	err = -EIO;
	357	dir_de = ext2_dotdot(old_inode, &dir_page);
	358	if (!dir_de)
	359	goto out_old;
	360	}
	361
	362	if (new_inode) {
	363	struct page *new_page;
	364	struct ext2_dir_entry_2 *new_de;
	365
	366	err = -ENOTEMPTY;
	367	if (dir_de && !ext2_empty_dir (new_inode))
	368	goto out_dir;
	369
	370	err = -ENOENT;
b4962091	371	new_de = ext2_find_entry(new_dir, &new_dentry->d_name, &new_page);
	372	if (IS_ERR(new_de)) {
	373	err = PTR_ERR(new_de);
	374	goto out_dir;
	375	}
1da177e4 LT	376	if (!new_de)
1da177e4 LT	377	goto out_dir;
39fe7557	378	ext2_set_link(new_dir, new_de, new_page, old_inode, 1);
02027d42	379	new_inode->i_ctime = current_time(new_inode);
1da177e4	380	if (dir_de)
9a53c3a7	381	drop_nlink(new_inode);
a513b035	382	inode_dec_link_count(new_inode);
1da177e4	383	} else {
1da177e4	384	err = ext2_add_link(new_dentry, old_inode);
e8a80c6f	385	if (err)
1da177e4	386	goto out_dir;
1da177e4	387	if (dir_de)
a513b035	388	inode_inc_link_count(new_dir);
1da177e4 LT	389	}
	390
	391	/*
	392	* Like most other Unix systems, set the ctime for inodes on a
	393	* rename.
1da177e4	394	*/
02027d42	395	old_inode->i_ctime = current_time(old_inode);
e8a80c6f	396	mark_inode_dirty(old_inode);
1da177e4 LT	397
1da177e4 LT	398	ext2_delete_entry (old_de, old_page);
1da177e4 LT	399
1da177e4 LT	400	if (dir_de) {
39fe7557 JK	401	if (old_dir != new_dir)
39fe7557 JK	402	ext2_set_link(old_inode, dir_de, dir_page, new_dir, 0);
9de6886e NP	403	else {
9de6886e NP	404	kunmap(dir_page);
09cbfeaf	405	put_page(dir_page);
9de6886e	406	}
a513b035	407	inode_dec_link_count(old_dir);
1da177e4 LT	408	}
	409	return 0;
	410
	411
	412	out_dir:
	413	if (dir_de) {
	414	kunmap(dir_page);
09cbfeaf	415	put_page(dir_page);
1da177e4 LT	416	}
	417	out_old:
	418	kunmap(old_page);
09cbfeaf	419	put_page(old_page);
1da177e4 LT	420	out:
	421	return err;
	422	}
	423
754661f1	424	const struct inode_operations ext2_dir_inode_operations = {
1da177e4 LT	425	.create = ext2_create,
	426	.lookup = ext2_lookup,
	427	.link = ext2_link,
	428	.unlink = ext2_unlink,
	429	.symlink = ext2_symlink,
	430	.mkdir = ext2_mkdir,
	431	.rmdir = ext2_rmdir,
	432	.mknod = ext2_mknod,
	433	.rename = ext2_rename,
1da177e4	434	.listxattr = ext2_listxattr,
93bc420e	435	.getattr = ext2_getattr,
1da177e4	436	.setattr = ext2_setattr,
4e34e719	437	.get_acl = ext2_get_acl,
64e178a7	438	.set_acl = ext2_set_acl,
60545d0d	439	.tmpfile = ext2_tmpfile,
1da177e4 LT	440	};
1da177e4 LT	441
754661f1	442	const struct inode_operations ext2_special_inode_operations = {
1da177e4	443	.listxattr = ext2_listxattr,
93bc420e	444	.getattr = ext2_getattr,
1da177e4	445	.setattr = ext2_setattr,
4e34e719	446	.get_acl = ext2_get_acl,
64e178a7	447	.set_acl = ext2_set_acl,
1da177e4	448	};