[linux-2.6-block.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
 * viro@parcelfarce.linux.theplanet.co.uk
 *
 * 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 (card@masi.ibp.fr)
 * 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 (davem@caip.rutgers.edu), 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) {
		unlock_new_inode(inode);
		d_instantiate(dentry, inode);
		return 0;
	}
	inode_dec_link_count(inode);
	unlock_new_inode(inode);
	iput(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);
	unlock_new_inode(inode);
	iput (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;

	unlock_new_inode(inode);
	d_instantiate(dentry, inode);
out:
	return err;

out_fail:
	inode_dec_link_count(inode);
	inode_dec_link_count(inode);
	unlock_new_inode(inode);
	iput(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	* viro@parcelfarce.linux.theplanet.co.uk
	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 (card@masi.ibp.fr)
	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 (davem@caip.rutgers.edu), 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) {
41080b5a	44	unlock_new_inode(inode);
8fc37ec5	45	d_instantiate(dentry, inode);
1da177e4 LT	46	return 0;
1da177e4 LT	47	}
a513b035	48	inode_dec_link_count(inode);
41080b5a	49	unlock_new_inode(inode);
1da177e4 LT	50	iput(inode);
	51	return err;
	52	}
	53
	54	/*
	55	* Methods themselves.
	56	*/
	57
00cd8dd3	58	static struct dentry ext2_lookup(struct inode dir, struct dentry *dentry, unsigned int flags)
1da177e4 LT	59	{
	60	struct inode * inode;
	61	ino_t ino;
	62
	63	if (dentry->d_name.len > EXT2_NAME_LEN)
	64	return ERR_PTR(-ENAMETOOLONG);
	65
a9885444	66	ino = ext2_inode_by_name(dir, &dentry->d_name);
1da177e4 LT	67	inode = NULL;
1da177e4 LT	68	if (ino) {
52fcf703	69	inode = ext2_iget(dir->i_sb, ino);
a9049376 AV	70	if (inode == ERR_PTR(-ESTALE)) {
	71	ext2_error(dir->i_sb, __func__,
	72	"deleted inode referenced: %lu",
	73	(unsigned long) ino);
	74	return ERR_PTR(-EIO);
4d6c13f8	75	}
1da177e4	76	}
082a05c6	77	return d_splice_alias(inode, dentry);
1da177e4 LT	78	}
	79
	80	struct dentry ext2_get_parent(struct dentry child)
	81	{
26fe5750	82	struct qstr dotdot = QSTR_INIT("..", 2);
2b0143b5	83	unsigned long ino = ext2_inode_by_name(d_inode(child), &dotdot);
1da177e4 LT	84	if (!ino)
1da177e4 LT	85	return ERR_PTR(-ENOENT);
fc64005c	86	return d_obtain_alias(ext2_iget(child->d_sb, ino));
1da177e4 LT	87	}
	88
	89	/*
	90	* By the time this is called, we already have created
	91	* the directory cache entry for the new file, but it
	92	* is so far negative - it has no inode.
	93	*
	94	* If the create succeeds, we fill in the inode information
	95	* with d_instantiate().
	96	*/
ebfc3b49	97	static int ext2_create (struct inode * dir, struct dentry * dentry, umode_t mode, bool excl)
1da177e4	98	{
907f4554	99	struct inode *inode;
c2edb305	100	int err;
907f4554	101
c2edb305 JK	102	err = dquot_initialize(dir);
	103	if (err)
	104	return err;
907f4554	105
2a7dba39	106	inode = ext2_new_inode(dir, mode, &dentry->d_name);
907f4554 CH	107	if (IS_ERR(inode))
	108	return PTR_ERR(inode);
	109
fb094c90	110	ext2_set_file_ops(inode);
907f4554 CH	111	mark_inode_dirty(inode);
907f4554 CH	112	return ext2_add_nondir(dentry, inode);
1da177e4 LT	113	}
1da177e4 LT	114
60545d0d AV	115	static int ext2_tmpfile(struct inode dir, struct dentry dentry, umode_t mode)
	116	{
	117	struct inode *inode = ext2_new_inode(dir, mode, NULL);
	118	if (IS_ERR(inode))
	119	return PTR_ERR(inode);
	120
fb094c90	121	ext2_set_file_ops(inode);
60545d0d AV	122	mark_inode_dirty(inode);
	123	d_tmpfile(dentry, inode);
	124	unlock_new_inode(inode);
	125	return 0;
	126	}
	127
1a67aafb	128	static int ext2_mknod (struct inode * dir, struct dentry *dentry, umode_t mode, dev_t rdev)
1da177e4 LT	129	{
	130	struct inode * inode;
	131	int err;
	132
c2edb305 JK	133	err = dquot_initialize(dir);
	134	if (err)
	135	return err;
907f4554	136
2a7dba39	137	inode = ext2_new_inode (dir, mode, &dentry->d_name);
1da177e4 LT	138	err = PTR_ERR(inode);
	139	if (!IS_ERR(inode)) {
	140	init_special_inode(inode, inode->i_mode, rdev);
	141	#ifdef CONFIG_EXT2_FS_XATTR
	142	inode->i_op = &ext2_special_inode_operations;
	143	#endif
	144	mark_inode_dirty(inode);
	145	err = ext2_add_nondir(dentry, inode);
	146	}
	147	return err;
	148	}
	149
	150	static int ext2_symlink (struct inode * dir, struct dentry * dentry,
	151	const char * symname)
	152	{
	153	struct super_block * sb = dir->i_sb;
	154	int err = -ENAMETOOLONG;
	155	unsigned l = strlen(symname)+1;
	156	struct inode * inode;
	157
	158	if (l > sb->s_blocksize)
	159	goto out;
	160
c2edb305 JK	161	err = dquot_initialize(dir);
	162	if (err)
	163	goto out;
907f4554	164
2a7dba39	165	inode = ext2_new_inode (dir, S_IFLNK \| S_IRWXUGO, &dentry->d_name);
1da177e4 LT	166	err = PTR_ERR(inode);
	167	if (IS_ERR(inode))
	168	goto out;
	169
	170	if (l > sizeof (EXT2_I(inode)->i_data)) {
	171	/* slow symlink */
	172	inode->i_op = &ext2_symlink_inode_operations;
21fc61c7	173	inode_nohighmem(inode);
1da177e4 LT	174	if (test_opt(inode->i_sb, NOBH))
	175	inode->i_mapping->a_ops = &ext2_nobh_aops;
	176	else
	177	inode->i_mapping->a_ops = &ext2_aops;
	178	err = page_symlink(inode, symname, l);
	179	if (err)
	180	goto out_fail;
	181	} else {
	182	/* fast symlink */
	183	inode->i_op = &ext2_fast_symlink_inode_operations;
cbe0fa38 AV	184	inode->i_link = (char*)EXT2_I(inode)->i_data;
cbe0fa38 AV	185	memcpy(inode->i_link, symname, l);
1da177e4 LT	186	inode->i_size = l-1;
	187	}
	188	mark_inode_dirty(inode);
	189
	190	err = ext2_add_nondir(dentry, inode);
	191	out:
	192	return err;
	193
	194	out_fail:
a513b035	195	inode_dec_link_count(inode);
41080b5a	196	unlock_new_inode(inode);
1da177e4 LT	197	iput (inode);
	198	goto out;
	199	}
	200
	201	static int ext2_link (struct dentry * old_dentry, struct inode * dir,
	202	struct dentry *dentry)
	203	{
2b0143b5	204	struct inode *inode = d_inode(old_dentry);
41080b5a	205	int err;
1da177e4	206
c2edb305 JK	207	err = dquot_initialize(dir);
	208	if (err)
	209	return err;
907f4554	210
02027d42	211	inode->i_ctime = current_time(inode);
a513b035	212	inode_inc_link_count(inode);
7de9c6ee	213	ihold(inode);
1da177e4	214
41080b5a AV	215	err = ext2_add_link(dentry, inode);
	216	if (!err) {
	217	d_instantiate(dentry, inode);
	218	return 0;
	219	}
	220	inode_dec_link_count(inode);
	221	iput(inode);
	222	return err;
1da177e4 LT	223	}
1da177e4 LT	224
18bb1db3	225	static int ext2_mkdir(struct inode * dir, struct dentry * dentry, umode_t mode)
1da177e4 LT	226	{
1da177e4 LT	227	struct inode * inode;
8de52778	228	int err;
1da177e4	229
c2edb305 JK	230	err = dquot_initialize(dir);
	231	if (err)
	232	return err;
907f4554	233
a513b035	234	inode_inc_link_count(dir);
1da177e4	235
2a7dba39	236	inode = ext2_new_inode(dir, S_IFDIR \| mode, &dentry->d_name);
1da177e4 LT	237	err = PTR_ERR(inode);
	238	if (IS_ERR(inode))
	239	goto out_dir;
	240
	241	inode->i_op = &ext2_dir_inode_operations;
	242	inode->i_fop = &ext2_dir_operations;
	243	if (test_opt(inode->i_sb, NOBH))
	244	inode->i_mapping->a_ops = &ext2_nobh_aops;
	245	else
	246	inode->i_mapping->a_ops = &ext2_aops;
	247
a513b035	248	inode_inc_link_count(inode);
1da177e4 LT	249
	250	err = ext2_make_empty(inode, dir);
	251	if (err)
	252	goto out_fail;
	253
	254	err = ext2_add_link(dentry, inode);
	255	if (err)
	256	goto out_fail;
	257
41080b5a	258	unlock_new_inode(inode);
8fc37ec5	259	d_instantiate(dentry, inode);
1da177e4 LT	260	out:
	261	return err;
	262
	263	out_fail:
a513b035 AD	264	inode_dec_link_count(inode);
a513b035 AD	265	inode_dec_link_count(inode);
41080b5a	266	unlock_new_inode(inode);
1da177e4 LT	267	iput(inode);
1da177e4 LT	268	out_dir:
a513b035	269	inode_dec_link_count(dir);
1da177e4 LT	270	goto out;
	271	}
	272
	273	static int ext2_unlink(struct inode * dir, struct dentry *dentry)
	274	{
2b0143b5	275	struct inode * inode = d_inode(dentry);
1da177e4 LT	276	struct ext2_dir_entry_2 * de;
1da177e4 LT	277	struct page * page;
c2edb305	278	int err;
1da177e4	279
c2edb305 JK	280	err = dquot_initialize(dir);
	281	if (err)
	282	goto out;
907f4554	283
a9885444	284	de = ext2_find_entry (dir, &dentry->d_name, &page);
c2edb305 JK	285	if (!de) {
c2edb305 JK	286	err = -ENOENT;
1da177e4	287	goto out;
c2edb305	288	}
1da177e4 LT	289
	290	err = ext2_delete_entry (de, page);
	291	if (err)
	292	goto out;
	293
	294	inode->i_ctime = dir->i_ctime;
a513b035	295	inode_dec_link_count(inode);
1da177e4 LT	296	err = 0;
	297	out:
	298	return err;
	299	}
	300
	301	static int ext2_rmdir (struct inode * dir, struct dentry *dentry)
	302	{
2b0143b5	303	struct inode * inode = d_inode(dentry);
1da177e4 LT	304	int err = -ENOTEMPTY;
	305
	306	if (ext2_empty_dir(inode)) {
	307	err = ext2_unlink(dir, dentry);
	308	if (!err) {
	309	inode->i_size = 0;
a513b035 AD	310	inode_dec_link_count(inode);
a513b035 AD	311	inode_dec_link_count(dir);
1da177e4 LT	312	}
	313	}
	314	return err;
	315	}
	316
	317	static int ext2_rename (struct inode * old_dir, struct dentry * old_dentry,
f03b8ad8 MS	318	struct inode * new_dir, struct dentry * new_dentry,
f03b8ad8 MS	319	unsigned int flags)
1da177e4	320	{
2b0143b5 DH	321	struct inode * old_inode = d_inode(old_dentry);
2b0143b5 DH	322	struct inode * new_inode = d_inode(new_dentry);
1da177e4 LT	323	struct page * dir_page = NULL;
	324	struct ext2_dir_entry_2 * dir_de = NULL;
	325	struct page * old_page;
	326	struct ext2_dir_entry_2 * old_de;
c2edb305	327	int err;
1da177e4	328
f03b8ad8 MS	329	if (flags & ~RENAME_NOREPLACE)
	330	return -EINVAL;
	331
c2edb305 JK	332	err = dquot_initialize(old_dir);
	333	if (err)
	334	goto out;
	335
	336	err = dquot_initialize(new_dir);
	337	if (err)
	338	goto out;
907f4554	339
a9885444	340	old_de = ext2_find_entry (old_dir, &old_dentry->d_name, &old_page);
c2edb305 JK	341	if (!old_de) {
c2edb305 JK	342	err = -ENOENT;
1da177e4	343	goto out;
c2edb305	344	}
1da177e4 LT	345
	346	if (S_ISDIR(old_inode->i_mode)) {
	347	err = -EIO;
	348	dir_de = ext2_dotdot(old_inode, &dir_page);
	349	if (!dir_de)
	350	goto out_old;
	351	}
	352
	353	if (new_inode) {
	354	struct page *new_page;
	355	struct ext2_dir_entry_2 *new_de;
	356
	357	err = -ENOTEMPTY;
	358	if (dir_de && !ext2_empty_dir (new_inode))
	359	goto out_dir;
	360
	361	err = -ENOENT;
a9885444	362	new_de = ext2_find_entry (new_dir, &new_dentry->d_name, &new_page);
1da177e4 LT	363	if (!new_de)
1da177e4 LT	364	goto out_dir;
39fe7557	365	ext2_set_link(new_dir, new_de, new_page, old_inode, 1);
02027d42	366	new_inode->i_ctime = current_time(new_inode);
1da177e4	367	if (dir_de)
9a53c3a7	368	drop_nlink(new_inode);
a513b035	369	inode_dec_link_count(new_inode);
1da177e4	370	} else {
1da177e4	371	err = ext2_add_link(new_dentry, old_inode);
e8a80c6f	372	if (err)
1da177e4	373	goto out_dir;
1da177e4	374	if (dir_de)
a513b035	375	inode_inc_link_count(new_dir);
1da177e4 LT	376	}
	377
	378	/*
	379	* Like most other Unix systems, set the ctime for inodes on a
	380	* rename.
1da177e4	381	*/
02027d42	382	old_inode->i_ctime = current_time(old_inode);
e8a80c6f	383	mark_inode_dirty(old_inode);
1da177e4 LT	384
1da177e4 LT	385	ext2_delete_entry (old_de, old_page);
1da177e4 LT	386
1da177e4 LT	387	if (dir_de) {
39fe7557 JK	388	if (old_dir != new_dir)
39fe7557 JK	389	ext2_set_link(old_inode, dir_de, dir_page, new_dir, 0);
9de6886e NP	390	else {
9de6886e NP	391	kunmap(dir_page);
09cbfeaf	392	put_page(dir_page);
9de6886e	393	}
a513b035	394	inode_dec_link_count(old_dir);
1da177e4 LT	395	}
	396	return 0;
	397
	398
	399	out_dir:
	400	if (dir_de) {
	401	kunmap(dir_page);
09cbfeaf	402	put_page(dir_page);
1da177e4 LT	403	}
	404	out_old:
	405	kunmap(old_page);
09cbfeaf	406	put_page(old_page);
1da177e4 LT	407	out:
	408	return err;
	409	}
	410
754661f1	411	const struct inode_operations ext2_dir_inode_operations = {
1da177e4 LT	412	.create = ext2_create,
	413	.lookup = ext2_lookup,
	414	.link = ext2_link,
	415	.unlink = ext2_unlink,
	416	.symlink = ext2_symlink,
	417	.mkdir = ext2_mkdir,
	418	.rmdir = ext2_rmdir,
	419	.mknod = ext2_mknod,
	420	.rename = ext2_rename,
	421	#ifdef CONFIG_EXT2_FS_XATTR
1da177e4	422	.listxattr = ext2_listxattr,
1da177e4 LT	423	#endif
1da177e4 LT	424	.setattr = ext2_setattr,
4e34e719	425	.get_acl = ext2_get_acl,
64e178a7	426	.set_acl = ext2_set_acl,
60545d0d	427	.tmpfile = ext2_tmpfile,
1da177e4 LT	428	};
1da177e4 LT	429
754661f1	430	const struct inode_operations ext2_special_inode_operations = {
1da177e4	431	#ifdef CONFIG_EXT2_FS_XATTR
1da177e4	432	.listxattr = ext2_listxattr,
1da177e4 LT	433	#endif
1da177e4 LT	434	.setattr = ext2_setattr,
4e34e719	435	.get_acl = ext2_get_acl,
64e178a7	436	.set_acl = ext2_set_acl,
1da177e4	437	};