[linux-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) {
		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;
	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) {
		if (res != -ENOENT)
			return ERR_PTR(res);
		inode = NULL;
	} else {
		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)
{
	ino_t ino;
	int res;

	res = ext2_inode_by_name(d_inode(child), &dotdot_name, &ino);
	if (res)
		return ERR_PTR(res);

	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 mnt_idmap * idmap,
			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 mnt_idmap *idmap, struct inode *dir,
			struct file *file, 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(file, inode);
	unlock_new_inode(inode);
	return finish_open_simple(file, 0);
}

static int ext2_mknod (struct mnt_idmap * idmap, 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 mnt_idmap * idmap, 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);
		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 mnt_idmap * idmap,
	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;
	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;
	void *page_addr;
	int err;

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

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

	err = ext2_delete_entry (de, page, page_addr);
	ext2_put_page(page, page_addr);
	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 mnt_idmap * idmap,
			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;
	void *dir_page_addr;
	struct ext2_dir_entry_2 * dir_de = NULL;
	struct page * old_page;
	void *old_page_addr;
	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,
				 &old_page_addr);
	if (IS_ERR(old_de)) {
		err = PTR_ERR(old_de);
		goto out;
	}

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

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

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

		new_de = ext2_find_entry(new_dir, &new_dentry->d_name,
					 &new_page, &page_addr);
		if (IS_ERR(new_de)) {
			err = PTR_ERR(new_de);
			goto out_dir;
		}
		err = ext2_set_link(new_dir, new_de, new_page, page_addr,
				    old_inode, true);
		ext2_put_page(new_page, page_addr);
		if (err)
			goto out_dir;
		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, old_page_addr);

	if (dir_de) {
		if (old_dir != new_dir) {
			err = ext2_set_link(old_inode, dir_de, dir_page,
					    dir_page_addr, new_dir, false);

		}
		ext2_put_page(dir_page, dir_page_addr);
		inode_dec_link_count(old_dir);
	}

out_old:
	ext2_put_page(old_page, old_page_addr);
out:
	return err;

out_dir:
	if (dir_de)
		ext2_put_page(dir_page, dir_page_addr);
	goto out_old;
}

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_inode_acl	= ext2_get_acl,
	.set_acl	= ext2_set_acl,
	.tmpfile	= ext2_tmpfile,
	.fileattr_get	= ext2_fileattr_get,
	.fileattr_set	= ext2_fileattr_set,
};

const struct inode_operations ext2_special_inode_operations = {
	.listxattr	= ext2_listxattr,
	.getattr	= ext2_getattr,
	.setattr	= ext2_setattr,
	.get_inode_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) {
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;
a43850a3	59	ino_t ino;
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);
a43850a3	66	if (res) {
	67	if (res != -ENOENT)
	68	return ERR_PTR(res);
	69	inode = NULL;
	70	} else {
52fcf703	71	inode = ext2_iget(dir->i_sb, ino);
a9049376 AV	72	if (inode == ERR_PTR(-ESTALE)) {
	73	ext2_error(dir->i_sb, __func__,
	74	"deleted inode referenced: %lu",
	75	(unsigned long) ino);
	76	return ERR_PTR(-EIO);
4d6c13f8	77	}
1da177e4	78	}
082a05c6	79	return d_splice_alias(inode, dentry);
1da177e4 LT	80	}
	81
	82	struct dentry ext2_get_parent(struct dentry child)
	83	{
a43850a3	84	ino_t ino;
b4962091	85	int res;
b4962091	86
80e5d1ff	87	res = ext2_inode_by_name(d_inode(child), &dotdot_name, &ino);
b4962091	88	if (res)
b4962091	89	return ERR_PTR(res);
a43850a3	90
fc64005c	91	return d_obtain_alias(ext2_iget(child->d_sb, ino));
1da177e4 LT	92	}
	93
	94	/*
	95	* By the time this is called, we already have created
	96	* the directory cache entry for the new file, but it
	97	* is so far negative - it has no inode.
	98	*
	99	* If the create succeeds, we fill in the inode information
	100	* with d_instantiate().
	101	*/
6c960e68	102	static int ext2_create (struct mnt_idmap * idmap,
549c7297 CB	103	struct inode * dir, struct dentry * dentry,
549c7297 CB	104	umode_t mode, bool excl)
1da177e4	105	{
907f4554	106	struct inode *inode;
c2edb305	107	int err;
907f4554	108
c2edb305 JK	109	err = dquot_initialize(dir);
	110	if (err)
	111	return err;
907f4554	112
2a7dba39	113	inode = ext2_new_inode(dir, mode, &dentry->d_name);
907f4554 CH	114	if (IS_ERR(inode))
	115	return PTR_ERR(inode);
	116
fb094c90	117	ext2_set_file_ops(inode);
907f4554 CH	118	mark_inode_dirty(inode);
907f4554 CH	119	return ext2_add_nondir(dentry, inode);
1da177e4 LT	120	}
1da177e4 LT	121
011e2b71	122	static int ext2_tmpfile(struct mnt_idmap idmap, struct inode dir,
863f144f	123	struct file *file, umode_t mode)
60545d0d AV	124	{
	125	struct inode *inode = ext2_new_inode(dir, mode, NULL);
	126	if (IS_ERR(inode))
	127	return PTR_ERR(inode);
	128
fb094c90	129	ext2_set_file_ops(inode);
60545d0d	130	mark_inode_dirty(inode);
863f144f	131	d_tmpfile(file, inode);
60545d0d	132	unlock_new_inode(inode);
863f144f	133	return finish_open_simple(file, 0);
60545d0d AV	134	}
60545d0d AV	135
5ebb29be	136	static int ext2_mknod (struct mnt_idmap * idmap, struct inode * dir,
549c7297	137	struct dentry *dentry, umode_t mode, dev_t rdev)
1da177e4 LT	138	{
	139	struct inode * inode;
	140	int err;
	141
c2edb305 JK	142	err = dquot_initialize(dir);
	143	if (err)
	144	return err;
907f4554	145
2a7dba39	146	inode = ext2_new_inode (dir, mode, &dentry->d_name);
1da177e4 LT	147	err = PTR_ERR(inode);
	148	if (!IS_ERR(inode)) {
	149	init_special_inode(inode, inode->i_mode, rdev);
1da177e4	150	inode->i_op = &ext2_special_inode_operations;
1da177e4 LT	151	mark_inode_dirty(inode);
	152	err = ext2_add_nondir(dentry, inode);
	153	}
	154	return err;
	155	}
	156
7a77db95	157	static int ext2_symlink (struct mnt_idmap * idmap, struct inode * dir,
549c7297	158	struct dentry * dentry, const char * symname)
1da177e4 LT	159	{
	160	struct super_block * sb = dir->i_sb;
	161	int err = -ENAMETOOLONG;
	162	unsigned l = strlen(symname)+1;
	163	struct inode * inode;
	164
	165	if (l > sb->s_blocksize)
	166	goto out;
	167
c2edb305 JK	168	err = dquot_initialize(dir);
	169	if (err)
	170	goto out;
907f4554	171
2a7dba39	172	inode = ext2_new_inode (dir, S_IFLNK \| S_IRWXUGO, &dentry->d_name);
1da177e4 LT	173	err = PTR_ERR(inode);
	174	if (IS_ERR(inode))
	175	goto out;
	176
	177	if (l > sizeof (EXT2_I(inode)->i_data)) {
	178	/* slow symlink */
	179	inode->i_op = &ext2_symlink_inode_operations;
21fc61c7	180	inode_nohighmem(inode);
0cc5b4ce	181	inode->i_mapping->a_ops = &ext2_aops;
1da177e4 LT	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
c54bd91e	228	static int ext2_mkdir(struct mnt_idmap * idmap,
549c7297	229	struct inode * dir, struct dentry * dentry, umode_t mode)
1da177e4 LT	230	{
1da177e4 LT	231	struct inode * inode;
8de52778	232	int err;
1da177e4	233
c2edb305 JK	234	err = dquot_initialize(dir);
	235	if (err)
	236	return err;
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;
0cc5b4ce	247	inode->i_mapping->a_ops = &ext2_aops;
1da177e4	248
a513b035	249	inode_inc_link_count(inode);
1da177e4 LT	250
	251	err = ext2_make_empty(inode, dir);
	252	if (err)
	253	goto out_fail;
	254
	255	err = ext2_add_link(dentry, inode);
	256	if (err)
	257	goto out_fail;
	258
1e2e547a	259	d_instantiate_new(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);
2e5afe54	266	discard_new_inode(inode);
1da177e4	267	out_dir:
a513b035	268	inode_dec_link_count(dir);
1da177e4 LT	269	goto out;
	270	}
	271
	272	static int ext2_unlink(struct inode * dir, struct dentry *dentry)
	273	{
2b0143b5	274	struct inode * inode = d_inode(dentry);
1da177e4 LT	275	struct ext2_dir_entry_2 * de;
1da177e4 LT	276	struct page * page;
782b76d7	277	void *page_addr;
c2edb305	278	int err;
1da177e4	279
c2edb305 JK	280	err = dquot_initialize(dir);
	281	if (err)
	282	goto out;
907f4554	283
782b76d7	284	de = ext2_find_entry(dir, &dentry->d_name, &page, &page_addr);
b4962091	285	if (IS_ERR(de)) {
	286	err = PTR_ERR(de);
	287	goto out;
	288	}
1da177e4	289
728d392f	290	err = ext2_delete_entry (de, page, page_addr);
782b76d7	291	ext2_put_page(page, page_addr);
1da177e4 LT	292	if (err)
	293	goto out;
	294
	295	inode->i_ctime = dir->i_ctime;
a513b035	296	inode_dec_link_count(inode);
1da177e4 LT	297	err = 0;
	298	out:
	299	return err;
	300	}
	301
	302	static int ext2_rmdir (struct inode * dir, struct dentry *dentry)
	303	{
2b0143b5	304	struct inode * inode = d_inode(dentry);
1da177e4 LT	305	int err = -ENOTEMPTY;
	306
	307	if (ext2_empty_dir(inode)) {
	308	err = ext2_unlink(dir, dentry);
	309	if (!err) {
	310	inode->i_size = 0;
a513b035 AD	311	inode_dec_link_count(inode);
a513b035 AD	312	inode_dec_link_count(dir);
1da177e4 LT	313	}
	314	}
	315	return err;
	316	}
	317
e18275ae	318	static int ext2_rename (struct mnt_idmap * idmap,
549c7297 CB	319	struct inode * old_dir, struct dentry * old_dentry,
549c7297 CB	320	struct inode * new_dir, struct dentry * new_dentry,
f03b8ad8	321	unsigned int flags)
1da177e4	322	{
2b0143b5 DH	323	struct inode * old_inode = d_inode(old_dentry);
2b0143b5 DH	324	struct inode * new_inode = d_inode(new_dentry);
1da177e4	325	struct page * dir_page = NULL;
782b76d7	326	void *dir_page_addr;
1da177e4 LT	327	struct ext2_dir_entry_2 * dir_de = NULL;
1da177e4 LT	328	struct page * old_page;
782b76d7	329	void *old_page_addr;
1da177e4	330	struct ext2_dir_entry_2 * old_de;
c2edb305	331	int err;
1da177e4	332
f03b8ad8 MS	333	if (flags & ~RENAME_NOREPLACE)
	334	return -EINVAL;
	335
c2edb305 JK	336	err = dquot_initialize(old_dir);
	337	if (err)
	338	goto out;
	339
	340	err = dquot_initialize(new_dir);
	341	if (err)
	342	goto out;
907f4554	343
782b76d7 IW	344	old_de = ext2_find_entry(old_dir, &old_dentry->d_name, &old_page,
782b76d7 IW	345	&old_page_addr);
b4962091	346	if (IS_ERR(old_de)) {
	347	err = PTR_ERR(old_de);
	348	goto out;
	349	}
1da177e4 LT	350
	351	if (S_ISDIR(old_inode->i_mode)) {
	352	err = -EIO;
782b76d7	353	dir_de = ext2_dotdot(old_inode, &dir_page, &dir_page_addr);
1da177e4 LT	354	if (!dir_de)
	355	goto out_old;
	356	}
	357
	358	if (new_inode) {
782b76d7	359	void *page_addr;
1da177e4 LT	360	struct page *new_page;
	361	struct ext2_dir_entry_2 *new_de;
	362
	363	err = -ENOTEMPTY;
	364	if (dir_de && !ext2_empty_dir (new_inode))
	365	goto out_dir;
	366
782b76d7 IW	367	new_de = ext2_find_entry(new_dir, &new_dentry->d_name,
782b76d7 IW	368	&new_page, &page_addr);
b4962091	369	if (IS_ERR(new_de)) {
	370	err = PTR_ERR(new_de);
	371	goto out_dir;
	372	}
7a5fa171 CH	373	err = ext2_set_link(new_dir, new_de, new_page, page_addr,
7a5fa171 CH	374	old_inode, true);
782b76d7	375	ext2_put_page(new_page, page_addr);
7a5fa171 CH	376	if (err)
7a5fa171 CH	377	goto out_dir;
02027d42	378	new_inode->i_ctime = current_time(new_inode);
1da177e4	379	if (dir_de)
9a53c3a7	380	drop_nlink(new_inode);
a513b035	381	inode_dec_link_count(new_inode);
1da177e4	382	} else {
1da177e4	383	err = ext2_add_link(new_dentry, old_inode);
e8a80c6f	384	if (err)
1da177e4	385	goto out_dir;
1da177e4	386	if (dir_de)
a513b035	387	inode_inc_link_count(new_dir);
1da177e4 LT	388	}
	389
	390	/*
	391	* Like most other Unix systems, set the ctime for inodes on a
	392	* rename.
1da177e4	393	*/
02027d42	394	old_inode->i_ctime = current_time(old_inode);
e8a80c6f	395	mark_inode_dirty(old_inode);
1da177e4	396
728d392f	397	ext2_delete_entry(old_de, old_page, old_page_addr);
1da177e4 LT	398
1da177e4 LT	399	if (dir_de) {
7a5fa171 CH	400	if (old_dir != new_dir) {
	401	err = ext2_set_link(old_inode, dir_de, dir_page,
	402	dir_page_addr, new_dir, false);
e2ebb123	403
7a5fa171	404	}
782b76d7	405	ext2_put_page(dir_page, dir_page_addr);
a513b035	406	inode_dec_link_count(old_dir);
1da177e4	407	}
1da177e4	408
7a5fa171	409	out_old:
782b76d7	410	ext2_put_page(old_page, old_page_addr);
7a5fa171 CH	411	out:
7a5fa171 CH	412	return err;
1da177e4 LT	413
1da177e4 LT	414	out_dir:
a6fbd0ab	415	if (dir_de)
782b76d7	416	ext2_put_page(dir_page, dir_page_addr);
7a5fa171	417	goto out_old;
1da177e4 LT	418	}
1da177e4 LT	419
754661f1	420	const struct inode_operations ext2_dir_inode_operations = {
1da177e4 LT	421	.create = ext2_create,
	422	.lookup = ext2_lookup,
	423	.link = ext2_link,
	424	.unlink = ext2_unlink,
	425	.symlink = ext2_symlink,
	426	.mkdir = ext2_mkdir,
	427	.rmdir = ext2_rmdir,
	428	.mknod = ext2_mknod,
	429	.rename = ext2_rename,
1da177e4	430	.listxattr = ext2_listxattr,
93bc420e	431	.getattr = ext2_getattr,
1da177e4	432	.setattr = ext2_setattr,
cac2f8b8	433	.get_inode_acl = ext2_get_acl,
64e178a7	434	.set_acl = ext2_set_acl,
60545d0d	435	.tmpfile = ext2_tmpfile,
aba405e3 MS	436	.fileattr_get = ext2_fileattr_get,
aba405e3 MS	437	.fileattr_set = ext2_fileattr_set,
1da177e4 LT	438	};
1da177e4 LT	439
754661f1	440	const struct inode_operations ext2_special_inode_operations = {
1da177e4	441	.listxattr = ext2_listxattr,
93bc420e	442	.getattr = ext2_getattr,
1da177e4	443	.setattr = ext2_setattr,
cac2f8b8	444	.get_inode_acl = ext2_get_acl,
64e178a7	445	.set_acl = ext2_set_acl,
1da177e4	446	};