[deliverable/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
 * 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(d_inode(child)->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, umode_t mode, bool excl)
{
	struct inode *inode;

	dquot_initialize(dir);

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

	inode->i_op = &ext2_file_inode_operations;
	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);
	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);

	inode->i_op = &ext2_file_inode_operations;
	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);
	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;

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

	dquot_initialize(dir);

	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;

	dquot_initialize(dir);

	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;
		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;

	dquot_initialize(dir);

	inode->i_ctime = CURRENT_TIME_SEC;
	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;

	dquot_initialize(dir);

	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 = -ENOENT;

	dquot_initialize(dir);

	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 = 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 )
{
	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 = -ENOENT;

	dquot_initialize(old_dir);
	dquot_initialize(new_dir);

	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;
		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 {
		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_SEC;
	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);
			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,
	.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
	.setxattr	= generic_setxattr,
	.getxattr	= generic_getxattr,
	.listxattr	= ext2_listxattr,
	.removexattr	= generic_removexattr,
#endif
	.setattr	= ext2_setattr,
	.get_acl	= ext2_get_acl,
	.set_acl	= ext2_set_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	* viro@parcelfarce.linux.theplanet.co.uk
	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 (card@masi.ibp.fr)
	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 (davem@caip.rutgers.edu), 1995
	31	*/
	32
	33	#include <linux/pagemap.h>
907f4554	34	#include <linux/quotaops.h>
1da177e4 LT	35	#include "ext2.h"
	36	#include "xattr.h"
	37	#include "acl.h"
	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) {
41080b5a	43	unlock_new_inode(inode);
8fc37ec5	44	d_instantiate(dentry, 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
00cd8dd3	57	static struct dentry ext2_lookup(struct inode dir, struct dentry *dentry, unsigned int flags)
1da177e4 LT	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);
a9049376 AV	69	if (inode == ERR_PTR(-ESTALE)) {
	70	ext2_error(dir->i_sb, __func__,
	71	"deleted inode referenced: %lu",
	72	(unsigned long) ino);
	73	return ERR_PTR(-EIO);
4d6c13f8	74	}
1da177e4	75	}
082a05c6	76	return d_splice_alias(inode, dentry);
1da177e4 LT	77	}
	78
	79	struct dentry ext2_get_parent(struct dentry child)
	80	{
26fe5750	81	struct qstr dotdot = QSTR_INIT("..", 2);
2b0143b5	82	unsigned long ino = ext2_inode_by_name(d_inode(child), &dotdot);
1da177e4 LT	83	if (!ino)
1da177e4 LT	84	return ERR_PTR(-ENOENT);
2b0143b5	85	return d_obtain_alias(ext2_iget(d_inode(child)->i_sb, ino));
1da177e4 LT	86	}
	87
	88	/*
	89	* By the time this is called, we already have created
	90	* the directory cache entry for the new file, but it
	91	* is so far negative - it has no inode.
	92	*
	93	* If the create succeeds, we fill in the inode information
	94	* with d_instantiate().
	95	*/
ebfc3b49	96	static int ext2_create (struct inode * dir, struct dentry * dentry, umode_t mode, bool excl)
1da177e4	97	{
907f4554 CH	98	struct inode *inode;
907f4554 CH	99
871a2931	100	dquot_initialize(dir);
907f4554	101
2a7dba39	102	inode = ext2_new_inode(dir, mode, &dentry->d_name);
907f4554 CH	103	if (IS_ERR(inode))
	104	return PTR_ERR(inode);
	105
	106	inode->i_op = &ext2_file_inode_operations;
be64f884	107	if (test_opt(inode->i_sb, NOBH)) {
907f4554 CH	108	inode->i_mapping->a_ops = &ext2_nobh_aops;
	109	inode->i_fop = &ext2_file_operations;
	110	} else {
	111	inode->i_mapping->a_ops = &ext2_aops;
	112	inode->i_fop = &ext2_file_operations;
1da177e4	113	}
907f4554 CH	114	mark_inode_dirty(inode);
907f4554 CH	115	return ext2_add_nondir(dentry, inode);
1da177e4 LT	116	}
1da177e4 LT	117
60545d0d AV	118	static int ext2_tmpfile(struct inode dir, struct dentry dentry, umode_t mode)
	119	{
	120	struct inode *inode = ext2_new_inode(dir, mode, NULL);
	121	if (IS_ERR(inode))
	122	return PTR_ERR(inode);
	123
	124	inode->i_op = &ext2_file_inode_operations;
be64f884	125	if (test_opt(inode->i_sb, NOBH)) {
60545d0d AV	126	inode->i_mapping->a_ops = &ext2_nobh_aops;
	127	inode->i_fop = &ext2_file_operations;
	128	} else {
	129	inode->i_mapping->a_ops = &ext2_aops;
	130	inode->i_fop = &ext2_file_operations;
	131	}
	132	mark_inode_dirty(inode);
	133	d_tmpfile(dentry, inode);
	134	unlock_new_inode(inode);
	135	return 0;
	136	}
	137
1a67aafb	138	static int ext2_mknod (struct inode * dir, struct dentry *dentry, umode_t mode, dev_t rdev)
1da177e4 LT	139	{
	140	struct inode * inode;
	141	int err;
	142
	143	if (!new_valid_dev(rdev))
	144	return -EINVAL;
	145
871a2931	146	dquot_initialize(dir);
907f4554	147
2a7dba39	148	inode = ext2_new_inode (dir, mode, &dentry->d_name);
1da177e4 LT	149	err = PTR_ERR(inode);
	150	if (!IS_ERR(inode)) {
	151	init_special_inode(inode, inode->i_mode, rdev);
	152	#ifdef CONFIG_EXT2_FS_XATTR
	153	inode->i_op = &ext2_special_inode_operations;
	154	#endif
	155	mark_inode_dirty(inode);
	156	err = ext2_add_nondir(dentry, inode);
	157	}
	158	return err;
	159	}
	160
	161	static int ext2_symlink (struct inode * dir, struct dentry * dentry,
	162	const char * symname)
	163	{
	164	struct super_block * sb = dir->i_sb;
	165	int err = -ENAMETOOLONG;
	166	unsigned l = strlen(symname)+1;
	167	struct inode * inode;
	168
	169	if (l > sb->s_blocksize)
	170	goto out;
	171
871a2931	172	dquot_initialize(dir);
907f4554	173
2a7dba39	174	inode = ext2_new_inode (dir, S_IFLNK \| S_IRWXUGO, &dentry->d_name);
1da177e4 LT	175	err = PTR_ERR(inode);
	176	if (IS_ERR(inode))
	177	goto out;
	178
	179	if (l > sizeof (EXT2_I(inode)->i_data)) {
	180	/* slow symlink */
	181	inode->i_op = &ext2_symlink_inode_operations;
	182	if (test_opt(inode->i_sb, NOBH))
	183	inode->i_mapping->a_ops = &ext2_nobh_aops;
	184	else
	185	inode->i_mapping->a_ops = &ext2_aops;
	186	err = page_symlink(inode, symname, l);
	187	if (err)
	188	goto out_fail;
	189	} else {
	190	/* fast symlink */
	191	inode->i_op = &ext2_fast_symlink_inode_operations;
cbe0fa38 AV	192	inode->i_link = (char*)EXT2_I(inode)->i_data;
cbe0fa38 AV	193	memcpy(inode->i_link, symname, l);
1da177e4 LT	194	inode->i_size = l-1;
	195	}
	196	mark_inode_dirty(inode);
	197
	198	err = ext2_add_nondir(dentry, inode);
	199	out:
	200	return err;
	201
	202	out_fail:
a513b035	203	inode_dec_link_count(inode);
41080b5a	204	unlock_new_inode(inode);
1da177e4 LT	205	iput (inode);
	206	goto out;
	207	}
	208
	209	static int ext2_link (struct dentry * old_dentry, struct inode * dir,
	210	struct dentry *dentry)
	211	{
2b0143b5	212	struct inode *inode = d_inode(old_dentry);
41080b5a	213	int err;
1da177e4	214
871a2931	215	dquot_initialize(dir);
907f4554	216
1da177e4	217	inode->i_ctime = CURRENT_TIME_SEC;
a513b035	218	inode_inc_link_count(inode);
7de9c6ee	219	ihold(inode);
1da177e4	220
41080b5a AV	221	err = ext2_add_link(dentry, inode);
	222	if (!err) {
	223	d_instantiate(dentry, inode);
	224	return 0;
	225	}
	226	inode_dec_link_count(inode);
	227	iput(inode);
	228	return err;
1da177e4 LT	229	}
1da177e4 LT	230
18bb1db3	231	static int ext2_mkdir(struct inode * dir, struct dentry * dentry, umode_t mode)
1da177e4 LT	232	{
1da177e4 LT	233	struct inode * inode;
8de52778	234	int err;
1da177e4	235
871a2931	236	dquot_initialize(dir);
907f4554	237
a513b035	238	inode_inc_link_count(dir);
1da177e4	239
2a7dba39	240	inode = ext2_new_inode(dir, S_IFDIR \| mode, &dentry->d_name);
1da177e4 LT	241	err = PTR_ERR(inode);
	242	if (IS_ERR(inode))
	243	goto out_dir;
	244
	245	inode->i_op = &ext2_dir_inode_operations;
	246	inode->i_fop = &ext2_dir_operations;
	247	if (test_opt(inode->i_sb, NOBH))
	248	inode->i_mapping->a_ops = &ext2_nobh_aops;
	249	else
	250	inode->i_mapping->a_ops = &ext2_aops;
	251
a513b035	252	inode_inc_link_count(inode);
1da177e4 LT	253
	254	err = ext2_make_empty(inode, dir);
	255	if (err)
	256	goto out_fail;
	257
	258	err = ext2_add_link(dentry, inode);
	259	if (err)
	260	goto out_fail;
	261
41080b5a	262	unlock_new_inode(inode);
8fc37ec5	263	d_instantiate(dentry, inode);
1da177e4 LT	264	out:
	265	return err;
	266
	267	out_fail:
a513b035 AD	268	inode_dec_link_count(inode);
a513b035 AD	269	inode_dec_link_count(inode);
41080b5a	270	unlock_new_inode(inode);
1da177e4 LT	271	iput(inode);
1da177e4 LT	272	out_dir:
a513b035	273	inode_dec_link_count(dir);
1da177e4 LT	274	goto out;
	275	}
	276
	277	static int ext2_unlink(struct inode * dir, struct dentry *dentry)
	278	{
2b0143b5	279	struct inode * inode = d_inode(dentry);
1da177e4 LT	280	struct ext2_dir_entry_2 * de;
	281	struct page * page;
	282	int err = -ENOENT;
	283
871a2931	284	dquot_initialize(dir);
907f4554	285
a9885444	286	de = ext2_find_entry (dir, &dentry->d_name, &page);
1da177e4 LT	287	if (!de)
	288	goto out;
	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,
	318	struct inode * new_dir, struct dentry * new_dentry )
	319	{
2b0143b5 DH	320	struct inode * old_inode = d_inode(old_dentry);
2b0143b5 DH	321	struct inode * new_inode = d_inode(new_dentry);
1da177e4 LT	322	struct page * dir_page = NULL;
	323	struct ext2_dir_entry_2 * dir_de = NULL;
	324	struct page * old_page;
	325	struct ext2_dir_entry_2 * old_de;
	326	int err = -ENOENT;
	327
871a2931 CH	328	dquot_initialize(old_dir);
871a2931 CH	329	dquot_initialize(new_dir);
907f4554	330
a9885444	331	old_de = ext2_find_entry (old_dir, &old_dentry->d_name, &old_page);
1da177e4 LT	332	if (!old_de)
	333	goto out;
	334
	335	if (S_ISDIR(old_inode->i_mode)) {
	336	err = -EIO;
	337	dir_de = ext2_dotdot(old_inode, &dir_page);
	338	if (!dir_de)
	339	goto out_old;
	340	}
	341
	342	if (new_inode) {
	343	struct page *new_page;
	344	struct ext2_dir_entry_2 *new_de;
	345
	346	err = -ENOTEMPTY;
	347	if (dir_de && !ext2_empty_dir (new_inode))
	348	goto out_dir;
	349
	350	err = -ENOENT;
a9885444	351	new_de = ext2_find_entry (new_dir, &new_dentry->d_name, &new_page);
1da177e4 LT	352	if (!new_de)
1da177e4 LT	353	goto out_dir;
39fe7557	354	ext2_set_link(new_dir, new_de, new_page, old_inode, 1);
1da177e4 LT	355	new_inode->i_ctime = CURRENT_TIME_SEC;
1da177e4 LT	356	if (dir_de)
9a53c3a7	357	drop_nlink(new_inode);
a513b035	358	inode_dec_link_count(new_inode);
1da177e4	359	} else {
1da177e4	360	err = ext2_add_link(new_dentry, old_inode);
e8a80c6f	361	if (err)
1da177e4	362	goto out_dir;
1da177e4	363	if (dir_de)
a513b035	364	inode_inc_link_count(new_dir);
1da177e4 LT	365	}
	366
	367	/*
	368	* Like most other Unix systems, set the ctime for inodes on a
	369	* rename.
1da177e4 LT	370	*/
1da177e4 LT	371	old_inode->i_ctime = CURRENT_TIME_SEC;
e8a80c6f	372	mark_inode_dirty(old_inode);
1da177e4 LT	373
1da177e4 LT	374	ext2_delete_entry (old_de, old_page);
1da177e4 LT	375
1da177e4 LT	376	if (dir_de) {
39fe7557 JK	377	if (old_dir != new_dir)
39fe7557 JK	378	ext2_set_link(old_inode, dir_de, dir_page, new_dir, 0);
9de6886e NP	379	else {
	380	kunmap(dir_page);
	381	page_cache_release(dir_page);
	382	}
a513b035	383	inode_dec_link_count(old_dir);
1da177e4 LT	384	}
	385	return 0;
	386
	387
	388	out_dir:
	389	if (dir_de) {
	390	kunmap(dir_page);
	391	page_cache_release(dir_page);
	392	}
	393	out_old:
	394	kunmap(old_page);
	395	page_cache_release(old_page);
	396	out:
	397	return err;
	398	}
	399
754661f1	400	const struct inode_operations ext2_dir_inode_operations = {
1da177e4 LT	401	.create = ext2_create,
	402	.lookup = ext2_lookup,
	403	.link = ext2_link,
	404	.unlink = ext2_unlink,
	405	.symlink = ext2_symlink,
	406	.mkdir = ext2_mkdir,
	407	.rmdir = ext2_rmdir,
	408	.mknod = ext2_mknod,
	409	.rename = ext2_rename,
	410	#ifdef CONFIG_EXT2_FS_XATTR
	411	.setxattr = generic_setxattr,
	412	.getxattr = generic_getxattr,
	413	.listxattr = ext2_listxattr,
	414	.removexattr = generic_removexattr,
	415	#endif
	416	.setattr = ext2_setattr,
4e34e719	417	.get_acl = ext2_get_acl,
64e178a7	418	.set_acl = ext2_set_acl,
60545d0d	419	.tmpfile = ext2_tmpfile,
1da177e4 LT	420	};
1da177e4 LT	421
754661f1	422	const struct inode_operations ext2_special_inode_operations = {
1da177e4 LT	423	#ifdef CONFIG_EXT2_FS_XATTR
	424	.setxattr = generic_setxattr,
	425	.getxattr = generic_getxattr,
	426	.listxattr = ext2_listxattr,
	427	.removexattr = generic_removexattr,
	428	#endif
	429	.setattr = ext2_setattr,
4e34e719	430	.get_acl = ext2_get_acl,
64e178a7	431	.set_acl = ext2_set_acl,
1da177e4	432	};