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

/*
 * 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 "ext2.h"
#include "xattr.h"
#include "acl.h"
#include "xip.h"

static inline int ext2_add_nondir(struct dentry *dentry, struct inode *inode)
{
	int err = ext2_add_link(dentry, inode);
	if (!err) {
		d_instantiate(dentry, inode);
		unlock_new_inode(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, struct nameidata *nd)
{
	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 (unlikely(IS_ERR(inode))) {
			if (PTR_ERR(inode) == -ESTALE) {
				ext2_error(dir->i_sb, __func__,
						"deleted inode referenced: %lu",
						(unsigned long) ino);
				return ERR_PTR(-EIO);
			} else {
				return ERR_CAST(inode);
			}
		}
	}
	return d_splice_alias(inode, dentry);
}

struct dentry *ext2_get_parent(struct dentry *child)
{
	struct qstr dotdot = {.name = "..", .len = 2};
	unsigned long ino = ext2_inode_by_name(child->d_inode, &dotdot);
	if (!ino)
		return ERR_PTR(-ENOENT);
	return d_obtain_alias(ext2_iget(child->d_inode->i_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, int mode, struct nameidata *nd)
{
	struct inode * inode = ext2_new_inode (dir, mode);
	int err = PTR_ERR(inode);
	if (!IS_ERR(inode)) {
		inode->i_op = &ext2_file_inode_operations;
		if (ext2_use_xip(inode->i_sb)) {
			inode->i_mapping->a_ops = &ext2_aops_xip;
			inode->i_fop = &ext2_xip_file_operations;
		} else if (test_opt(inode->i_sb, NOBH)) {
			inode->i_mapping->a_ops = &ext2_nobh_aops;
			inode->i_fop = &ext2_file_operations;
		} else {
			inode->i_mapping->a_ops = &ext2_aops;
			inode->i_fop = &ext2_file_operations;
		}
		mark_inode_dirty(inode);
		err = ext2_add_nondir(dentry, inode);
	}
	return err;
}

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

	if (!new_valid_dev(rdev))
		return -EINVAL;

	inode = ext2_new_inode (dir, mode);
	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;

	inode = ext2_new_inode (dir, S_IFLNK | S_IRWXUGO);
	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;
		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;
		memcpy((char*)(EXT2_I(inode)->i_data),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 = old_dentry->d_inode;
	int err;

	if (inode->i_nlink >= EXT2_LINK_MAX)
		return -EMLINK;

	inode->i_ctime = CURRENT_TIME_SEC;
	inode_inc_link_count(inode);
	atomic_inc(&inode->i_count);

	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, int mode)
{
	struct inode * inode;
	int err = -EMLINK;

	if (dir->i_nlink >= EXT2_LINK_MAX)
		goto out;

	inode_inc_link_count(dir);

	inode = ext2_new_inode (dir, S_IFDIR | mode);
	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(dentry, inode);
	unlock_new_inode(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 = dentry->d_inode;
	struct ext2_dir_entry_2 * de;
	struct page * page;
	int err = -ENOENT;

	de = ext2_find_entry (dir, &dentry->d_name, &page);
	if (!de)
		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 = dentry->d_inode;
	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 )
{
	struct inode * old_inode = old_dentry->d_inode;
	struct inode * new_inode = new_dentry->d_inode;
	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 = -ENOENT;

	old_de = ext2_find_entry (old_dir, &old_dentry->d_name, &old_page);
	if (!old_de)
		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;
		inode_inc_link_count(old_inode);
		ext2_set_link(new_dir, new_de, new_page, old_inode, 1);
		new_inode->i_ctime = CURRENT_TIME_SEC;
		if (dir_de)
			drop_nlink(new_inode);
		inode_dec_link_count(new_inode);
	} else {
		if (dir_de) {
			err = -EMLINK;
			if (new_dir->i_nlink >= EXT2_LINK_MAX)
				goto out_dir;
		}
		inode_inc_link_count(old_inode);
		err = ext2_add_link(new_dentry, old_inode);
		if (err) {
			inode_dec_link_count(old_inode);
			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.
	 * inode_dec_link_count() will mark the inode dirty.
	 */
	old_inode->i_ctime = CURRENT_TIME_SEC;

	ext2_delete_entry (old_de, old_page);
	inode_dec_link_count(old_inode);

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


out_dir:
	if (dir_de) {
		kunmap(dir_page);
		page_cache_release(dir_page);
	}
out_old:
	kunmap(old_page);
	page_cache_release(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
	.setxattr	= generic_setxattr,
	.getxattr	= generic_getxattr,
	.listxattr	= ext2_listxattr,
	.removexattr	= generic_removexattr,
#endif
	.setattr	= ext2_setattr,
	.check_acl	= ext2_check_acl,
};

const struct inode_operations ext2_special_inode_operations = {
#ifdef CONFIG_EXT2_FS_XATTR
	.setxattr	= generic_setxattr,
	.getxattr	= generic_getxattr,
	.listxattr	= ext2_listxattr,
	.removexattr	= generic_removexattr,
#endif
	.setattr	= ext2_setattr,
	.check_acl	= ext2_check_acl,
};
Commit	Line	Data
1da177e4 LT	1	/*
	2	* linux/fs/ext2/namei.c
	3	*
	4	* Rewrite to pagecache. Almost all code had been changed, so blame me
	5	* if the things go wrong. Please, send bug reports to
	6	* [email protected]
	7	*
	8	* Stuff here is basically a glue between the VFS and generic UNIXish
	9	* filesystem that keeps everything in pagecache. All knowledge of the
	10	* directory layout is in fs/ext2/dir.c - it turned out to be easily separatable
	11	* and it's easier to debug that way. In principle we might want to
	12	* generalize that a bit and turn it into a library. Or not.
	13	*
	14	* The only non-static object here is ext2_dir_inode_operations.
	15	*
	16	* TODO: get rid of kmap() use, add readahead.
	17	*
	18	* Copyright (C) 1992, 1993, 1994, 1995
	19	* Remy Card ([email protected])
	20	* Laboratoire MASI - Institut Blaise Pascal
	21	* Universite Pierre et Marie Curie (Paris VI)
	22	*
	23	* from
	24	*
	25	* linux/fs/minix/namei.c
	26	*
	27	* Copyright (C) 1991, 1992 Linus Torvalds
	28	*
	29	* Big-endian to little-endian byte-swapping/bitmaps by
	30	* David S. Miller ([email protected]), 1995
	31	*/
	32
	33	#include <linux/pagemap.h>
	34	#include "ext2.h"
	35	#include "xattr.h"
	36	#include "acl.h"
6d79125b	37	#include "xip.h"
1da177e4	38
1da177e4 LT	39	static inline int ext2_add_nondir(struct dentry dentry, struct inode inode)
	40	{
	41	int err = ext2_add_link(dentry, inode);
	42	if (!err) {
	43	d_instantiate(dentry, inode);
41080b5a	44	unlock_new_inode(inode);
1da177e4 LT	45	return 0;
1da177e4 LT	46	}
a513b035	47	inode_dec_link_count(inode);
41080b5a	48	unlock_new_inode(inode);
1da177e4 LT	49	iput(inode);
	50	return err;
	51	}
	52
	53	/*
	54	* Methods themselves.
	55	*/
	56
	57	static struct dentry ext2_lookup(struct inode dir, struct dentry dentry, struct nameidata nd)
	58	{
	59	struct inode * inode;
	60	ino_t ino;
	61
	62	if (dentry->d_name.len > EXT2_NAME_LEN)
	63	return ERR_PTR(-ENAMETOOLONG);
	64
a9885444	65	ino = ext2_inode_by_name(dir, &dentry->d_name);
1da177e4 LT	66	inode = NULL;
1da177e4 LT	67	if (ino) {
52fcf703	68	inode = ext2_iget(dir->i_sb, ino);
4d6c13f8 BD	69	if (unlikely(IS_ERR(inode))) {
	70	if (PTR_ERR(inode) == -ESTALE) {
	71	ext2_error(dir->i_sb, __func__,
	72	"deleted inode referenced: %lu",
a4255e4c	73	(unsigned long) ino);
4d6c13f8 BD	74	return ERR_PTR(-EIO);
	75	} else {
	76	return ERR_CAST(inode);
	77	}
	78	}
1da177e4	79	}
082a05c6	80	return d_splice_alias(inode, dentry);
1da177e4 LT	81	}
	82
	83	struct dentry ext2_get_parent(struct dentry child)
	84	{
a9885444 AV	85	struct qstr dotdot = {.name = "..", .len = 2};
a9885444 AV	86	unsigned long ino = ext2_inode_by_name(child->d_inode, &dotdot);
1da177e4 LT	87	if (!ino)
1da177e4 LT	88	return ERR_PTR(-ENOENT);
44003728	89	return d_obtain_alias(ext2_iget(child->d_inode->i_sb, ino));
1da177e4 LT	90	}
	91
	92	/*
	93	* By the time this is called, we already have created
	94	* the directory cache entry for the new file, but it
	95	* is so far negative - it has no inode.
	96	*
	97	* If the create succeeds, we fill in the inode information
	98	* with d_instantiate().
	99	*/
	100	static int ext2_create (struct inode * dir, struct dentry * dentry, int mode, struct nameidata *nd)
	101	{
	102	struct inode * inode = ext2_new_inode (dir, mode);
	103	int err = PTR_ERR(inode);
	104	if (!IS_ERR(inode)) {
	105	inode->i_op = &ext2_file_inode_operations;
6d79125b CO	106	if (ext2_use_xip(inode->i_sb)) {
	107	inode->i_mapping->a_ops = &ext2_aops_xip;
	108	inode->i_fop = &ext2_xip_file_operations;
	109	} else if (test_opt(inode->i_sb, NOBH)) {
1da177e4	110	inode->i_mapping->a_ops = &ext2_nobh_aops;
6d79125b CO	111	inode->i_fop = &ext2_file_operations;
6d79125b CO	112	} else {
1da177e4	113	inode->i_mapping->a_ops = &ext2_aops;
6d79125b CO	114	inode->i_fop = &ext2_file_operations;
6d79125b CO	115	}
1da177e4 LT	116	mark_inode_dirty(inode);
	117	err = ext2_add_nondir(dentry, inode);
	118	}
	119	return err;
	120	}
	121
	122	static int ext2_mknod (struct inode * dir, struct dentry *dentry, int mode, dev_t rdev)
	123	{
	124	struct inode * inode;
	125	int err;
	126
	127	if (!new_valid_dev(rdev))
	128	return -EINVAL;
	129
	130	inode = ext2_new_inode (dir, mode);
	131	err = PTR_ERR(inode);
	132	if (!IS_ERR(inode)) {
	133	init_special_inode(inode, inode->i_mode, rdev);
	134	#ifdef CONFIG_EXT2_FS_XATTR
	135	inode->i_op = &ext2_special_inode_operations;
	136	#endif
	137	mark_inode_dirty(inode);
	138	err = ext2_add_nondir(dentry, inode);
	139	}
	140	return err;
	141	}
	142
	143	static int ext2_symlink (struct inode * dir, struct dentry * dentry,
	144	const char * symname)
	145	{
	146	struct super_block * sb = dir->i_sb;
	147	int err = -ENAMETOOLONG;
	148	unsigned l = strlen(symname)+1;
	149	struct inode * inode;
	150
	151	if (l > sb->s_blocksize)
	152	goto out;
	153
	154	inode = ext2_new_inode (dir, S_IFLNK \| S_IRWXUGO);
	155	err = PTR_ERR(inode);
	156	if (IS_ERR(inode))
	157	goto out;
	158
	159	if (l > sizeof (EXT2_I(inode)->i_data)) {
	160	/* slow symlink */
	161	inode->i_op = &ext2_symlink_inode_operations;
	162	if (test_opt(inode->i_sb, NOBH))
	163	inode->i_mapping->a_ops = &ext2_nobh_aops;
	164	else
	165	inode->i_mapping->a_ops = &ext2_aops;
	166	err = page_symlink(inode, symname, l);
	167	if (err)
	168	goto out_fail;
	169	} else {
	170	/* fast symlink */
	171	inode->i_op = &ext2_fast_symlink_inode_operations;
	172	memcpy((char*)(EXT2_I(inode)->i_data),symname,l);
	173	inode->i_size = l-1;
	174	}
	175	mark_inode_dirty(inode);
	176
	177	err = ext2_add_nondir(dentry, inode);
	178	out:
	179	return err;
180
181	out_fail:
a513b035	182	inode_dec_link_count(inode);
41080b5a	183	unlock_new_inode(inode);
1da177e4 LT	184	iput (inode);
	185	goto out;
	186	}
	187
	188	static int ext2_link (struct dentry * old_dentry, struct inode * dir,
	189	struct dentry *dentry)
	190	{
	191	struct inode *inode = old_dentry->d_inode;
41080b5a	192	int err;
1da177e4 LT	193
	194	if (inode->i_nlink >= EXT2_LINK_MAX)
	195	return -EMLINK;
	196
	197	inode->i_ctime = CURRENT_TIME_SEC;
a513b035	198	inode_inc_link_count(inode);
1da177e4 LT	199	atomic_inc(&inode->i_count);
1da177e4 LT	200
41080b5a AV	201	err = ext2_add_link(dentry, inode);
	202	if (!err) {
	203	d_instantiate(dentry, inode);
	204	return 0;
	205	}
	206	inode_dec_link_count(inode);
	207	iput(inode);
	208	return err;
1da177e4 LT	209	}
	210
	211	static int ext2_mkdir(struct inode * dir, struct dentry * dentry, int mode)
	212	{
	213	struct inode * inode;
	214	int err = -EMLINK;
	215
	216	if (dir->i_nlink >= EXT2_LINK_MAX)
	217	goto out;
	218
a513b035	219	inode_inc_link_count(dir);
1da177e4 LT	220
	221	inode = ext2_new_inode (dir, S_IFDIR \| mode);
	222	err = PTR_ERR(inode);
	223	if (IS_ERR(inode))
	224	goto out_dir;
	225
	226	inode->i_op = &ext2_dir_inode_operations;
	227	inode->i_fop = &ext2_dir_operations;
	228	if (test_opt(inode->i_sb, NOBH))
	229	inode->i_mapping->a_ops = &ext2_nobh_aops;
	230	else
	231	inode->i_mapping->a_ops = &ext2_aops;
	232
a513b035	233	inode_inc_link_count(inode);
1da177e4 LT	234
	235	err = ext2_make_empty(inode, dir);
	236	if (err)
	237	goto out_fail;
	238
	239	err = ext2_add_link(dentry, inode);
	240	if (err)
	241	goto out_fail;
	242
	243	d_instantiate(dentry, inode);
41080b5a	244	unlock_new_inode(inode);
1da177e4 LT	245	out:
	246	return err;
	247
	248	out_fail:
a513b035 AD	249	inode_dec_link_count(inode);
a513b035 AD	250	inode_dec_link_count(inode);
41080b5a	251	unlock_new_inode(inode);
1da177e4 LT	252	iput(inode);
1da177e4 LT	253	out_dir:
a513b035	254	inode_dec_link_count(dir);
1da177e4 LT	255	goto out;
	256	}
	257
	258	static int ext2_unlink(struct inode * dir, struct dentry *dentry)
	259	{
	260	struct inode * inode = dentry->d_inode;
	261	struct ext2_dir_entry_2 * de;
	262	struct page * page;
	263	int err = -ENOENT;
	264
a9885444	265	de = ext2_find_entry (dir, &dentry->d_name, &page);
1da177e4 LT	266	if (!de)
	267	goto out;
	268
	269	err = ext2_delete_entry (de, page);
	270	if (err)
	271	goto out;
	272
	273	inode->i_ctime = dir->i_ctime;
a513b035	274	inode_dec_link_count(inode);
1da177e4 LT	275	err = 0;
	276	out:
	277	return err;
	278	}
	279
	280	static int ext2_rmdir (struct inode * dir, struct dentry *dentry)
	281	{
	282	struct inode * inode = dentry->d_inode;
	283	int err = -ENOTEMPTY;
	284
	285	if (ext2_empty_dir(inode)) {
	286	err = ext2_unlink(dir, dentry);
	287	if (!err) {
	288	inode->i_size = 0;
a513b035 AD	289	inode_dec_link_count(inode);
a513b035 AD	290	inode_dec_link_count(dir);
1da177e4 LT	291	}
	292	}
	293	return err;
	294	}
	295
	296	static int ext2_rename (struct inode * old_dir, struct dentry * old_dentry,
	297	struct inode * new_dir, struct dentry * new_dentry )
	298	{
	299	struct inode * old_inode = old_dentry->d_inode;
	300	struct inode * new_inode = new_dentry->d_inode;
	301	struct page * dir_page = NULL;
	302	struct ext2_dir_entry_2 * dir_de = NULL;
	303	struct page * old_page;
	304	struct ext2_dir_entry_2 * old_de;
	305	int err = -ENOENT;
	306
a9885444	307	old_de = ext2_find_entry (old_dir, &old_dentry->d_name, &old_page);
1da177e4 LT	308	if (!old_de)
	309	goto out;
	310
	311	if (S_ISDIR(old_inode->i_mode)) {
	312	err = -EIO;
	313	dir_de = ext2_dotdot(old_inode, &dir_page);
	314	if (!dir_de)
	315	goto out_old;
	316	}
	317
	318	if (new_inode) {
	319	struct page *new_page;
	320	struct ext2_dir_entry_2 *new_de;
	321
	322	err = -ENOTEMPTY;
	323	if (dir_de && !ext2_empty_dir (new_inode))
	324	goto out_dir;
	325
	326	err = -ENOENT;
a9885444	327	new_de = ext2_find_entry (new_dir, &new_dentry->d_name, &new_page);
1da177e4 LT	328	if (!new_de)
1da177e4 LT	329	goto out_dir;
a513b035	330	inode_inc_link_count(old_inode);
39fe7557	331	ext2_set_link(new_dir, new_de, new_page, old_inode, 1);
1da177e4 LT	332	new_inode->i_ctime = CURRENT_TIME_SEC;
1da177e4 LT	333	if (dir_de)
9a53c3a7	334	drop_nlink(new_inode);
a513b035	335	inode_dec_link_count(new_inode);
1da177e4 LT	336	} else {
	337	if (dir_de) {
	338	err = -EMLINK;
	339	if (new_dir->i_nlink >= EXT2_LINK_MAX)
	340	goto out_dir;
	341	}
a513b035	342	inode_inc_link_count(old_inode);
1da177e4 LT	343	err = ext2_add_link(new_dentry, old_inode);
1da177e4 LT	344	if (err) {
a513b035	345	inode_dec_link_count(old_inode);
1da177e4 LT	346	goto out_dir;
	347	}
	348	if (dir_de)
a513b035	349	inode_inc_link_count(new_dir);
1da177e4 LT	350	}
	351
	352	/*
	353	* Like most other Unix systems, set the ctime for inodes on a
	354	* rename.
a513b035	355	* inode_dec_link_count() will mark the inode dirty.
1da177e4 LT	356	*/
	357	old_inode->i_ctime = CURRENT_TIME_SEC;
	358
	359	ext2_delete_entry (old_de, old_page);
a513b035	360	inode_dec_link_count(old_inode);
1da177e4 LT	361
1da177e4 LT	362	if (dir_de) {
39fe7557 JK	363	if (old_dir != new_dir)
39fe7557 JK	364	ext2_set_link(old_inode, dir_de, dir_page, new_dir, 0);
9de6886e NP	365	else {
	366	kunmap(dir_page);
	367	page_cache_release(dir_page);
	368	}
a513b035	369	inode_dec_link_count(old_dir);
1da177e4 LT	370	}
	371	return 0;
	372
	373
	374	out_dir:
	375	if (dir_de) {
	376	kunmap(dir_page);
	377	page_cache_release(dir_page);
	378	}
	379	out_old:
	380	kunmap(old_page);
	381	page_cache_release(old_page);
	382	out:
	383	return err;
	384	}
	385
754661f1	386	const struct inode_operations ext2_dir_inode_operations = {
1da177e4 LT	387	.create = ext2_create,
	388	.lookup = ext2_lookup,
	389	.link = ext2_link,
	390	.unlink = ext2_unlink,
	391	.symlink = ext2_symlink,
	392	.mkdir = ext2_mkdir,
	393	.rmdir = ext2_rmdir,
	394	.mknod = ext2_mknod,
	395	.rename = ext2_rename,
	396	#ifdef CONFIG_EXT2_FS_XATTR
	397	.setxattr = generic_setxattr,
	398	.getxattr = generic_getxattr,
	399	.listxattr = ext2_listxattr,
	400	.removexattr = generic_removexattr,
	401	#endif
	402	.setattr = ext2_setattr,
1d5ccd1c	403	.check_acl = ext2_check_acl,
1da177e4 LT	404	};
1da177e4 LT	405
754661f1	406	const struct inode_operations ext2_special_inode_operations = {
1da177e4 LT	407	#ifdef CONFIG_EXT2_FS_XATTR
	408	.setxattr = generic_setxattr,
	409	.getxattr = generic_getxattr,
	410	.listxattr = ext2_listxattr,
	411	.removexattr = generic_removexattr,
	412	#endif
	413	.setattr = ext2_setattr,
1d5ccd1c	414	.check_acl = ext2_check_acl,
1da177e4	415	};