[linux.git] / fs / nilfs2 / namei.c

/*
 * namei.c - NILFS pathname lookup operations.
 *
 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 * Modified for NILFS by Amagai Yoshiji <[email protected]>,
 *                       Ryusuke Konishi <[email protected]>
 */
/*
 *  linux/fs/ext2/namei.c
 *
 * 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 "nilfs.h"


static inline int nilfs_add_nondir(struct dentry *dentry, struct inode *inode)
{
	int err = nilfs_add_link(dentry, inode);
	if (!err) {
		d_instantiate(dentry, inode);
		return 0;
	}
	inode_dec_link_count(inode);
	iput(inode);
	return err;
}

/*
 * Methods themselves.
 */

static struct dentry *
nilfs_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
{
	struct inode *inode;
	ino_t ino;

	if (dentry->d_name.len > NILFS_NAME_LEN)
		return ERR_PTR(-ENAMETOOLONG);

	ino = nilfs_inode_by_name(dir, dentry);
	inode = NULL;
	if (ino) {
		inode = nilfs_iget(dir->i_sb, ino);
		if (IS_ERR(inode))
			return ERR_CAST(inode);
	}
	return d_splice_alias(inode, dentry);
}

struct dentry *nilfs_get_parent(struct dentry *child)
{
	unsigned long ino;
	struct inode *inode;
	struct dentry dotdot;

	dotdot.d_name.name = "..";
	dotdot.d_name.len = 2;

	ino = nilfs_inode_by_name(child->d_inode, &dotdot);
	if (!ino)
		return ERR_PTR(-ENOENT);

	inode = nilfs_iget(child->d_inode->i_sb, ino);
	if (IS_ERR(inode))
		return ERR_CAST(inode);
	return d_obtain_alias(inode);
}

/*
 * 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 nilfs_create(struct inode *dir, struct dentry *dentry, int mode,
			struct nameidata *nd)
{
	struct inode *inode;
	struct nilfs_transaction_info ti;
	int err;

	err = nilfs_transaction_begin(dir->i_sb, &ti, 1);
	if (err)
		return err;
	inode = nilfs_new_inode(dir, mode);
	err = PTR_ERR(inode);
	if (!IS_ERR(inode)) {
		inode->i_op = &nilfs_file_inode_operations;
		inode->i_fop = &nilfs_file_operations;
		inode->i_mapping->a_ops = &nilfs_aops;
		mark_inode_dirty(inode);
		err = nilfs_add_nondir(dentry, inode);
	}
	if (!err)
		err = nilfs_transaction_commit(dir->i_sb);
	else
		nilfs_transaction_abort(dir->i_sb);

	return err;
}

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

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

	err = nilfs_transaction_begin(dir->i_sb, &ti, 1);
	if (err)
		return err;
	inode = nilfs_new_inode(dir, mode);
	err = PTR_ERR(inode);
	if (!IS_ERR(inode)) {
		init_special_inode(inode, inode->i_mode, rdev);
		mark_inode_dirty(inode);
		err = nilfs_add_nondir(dentry, inode);
	}
	if (!err)
		err = nilfs_transaction_commit(dir->i_sb);
	else
		nilfs_transaction_abort(dir->i_sb);

	return err;
}

static int nilfs_symlink(struct inode *dir, struct dentry *dentry,
			 const char *symname)
{
	struct nilfs_transaction_info ti;
	struct super_block *sb = dir->i_sb;
	unsigned l = strlen(symname)+1;
	struct inode *inode;
	int err;

	if (l > sb->s_blocksize)
		return -ENAMETOOLONG;

	err = nilfs_transaction_begin(dir->i_sb, &ti, 1);
	if (err)
		return err;

	inode = nilfs_new_inode(dir, S_IFLNK | S_IRWXUGO);
	err = PTR_ERR(inode);
	if (IS_ERR(inode))
		goto out;

	/* slow symlink */
	inode->i_op = &nilfs_symlink_inode_operations;
	inode->i_mapping->a_ops = &nilfs_aops;
	err = page_symlink(inode, symname, l);
	if (err)
		goto out_fail;

	/* mark_inode_dirty(inode); */
	/* nilfs_new_inode() and page_symlink() do this */

	err = nilfs_add_nondir(dentry, inode);
out:
	if (!err)
		err = nilfs_transaction_commit(dir->i_sb);
	else
		nilfs_transaction_abort(dir->i_sb);

	return err;

out_fail:
	inode_dec_link_count(inode);
	iput(inode);
	goto out;
}

static int nilfs_link(struct dentry *old_dentry, struct inode *dir,
		      struct dentry *dentry)
{
	struct inode *inode = old_dentry->d_inode;
	struct nilfs_transaction_info ti;
	int err;

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

	err = nilfs_transaction_begin(dir->i_sb, &ti, 1);
	if (err)
		return err;

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

	err = nilfs_add_nondir(dentry, inode);
	if (!err)
		err = nilfs_transaction_commit(dir->i_sb);
	else
		nilfs_transaction_abort(dir->i_sb);

	return err;
}

static int nilfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
{
	struct inode *inode;
	struct nilfs_transaction_info ti;
	int err;

	if (dir->i_nlink >= NILFS_LINK_MAX)
		return -EMLINK;

	err = nilfs_transaction_begin(dir->i_sb, &ti, 1);
	if (err)
		return err;

	inode_inc_link_count(dir);

	inode = nilfs_new_inode(dir, S_IFDIR | mode);
	err = PTR_ERR(inode);
	if (IS_ERR(inode))
		goto out_dir;

	inode->i_op = &nilfs_dir_inode_operations;
	inode->i_fop = &nilfs_dir_operations;
	inode->i_mapping->a_ops = &nilfs_aops;

	inode_inc_link_count(inode);

	err = nilfs_make_empty(inode, dir);
	if (err)
		goto out_fail;

	err = nilfs_add_link(dentry, inode);
	if (err)
		goto out_fail;

	d_instantiate(dentry, inode);
out:
	if (!err)
		err = nilfs_transaction_commit(dir->i_sb);
	else
		nilfs_transaction_abort(dir->i_sb);

	return err;

out_fail:
	inode_dec_link_count(inode);
	inode_dec_link_count(inode);
	iput(inode);
out_dir:
	inode_dec_link_count(dir);
	goto out;
}

static int nilfs_unlink(struct inode *dir, struct dentry *dentry)
{
	struct inode *inode;
	struct nilfs_dir_entry *de;
	struct page *page;
	struct nilfs_transaction_info ti;
	int err;

	err = nilfs_transaction_begin(dir->i_sb, &ti, 0);
	if (err)
		return err;

	err = -ENOENT;
	de = nilfs_find_entry(dir, dentry, &page);
	if (!de)
		goto out;

	inode = dentry->d_inode;
	err = -EIO;
	if (le64_to_cpu(de->inode) != inode->i_ino)
		goto out;

	if (!inode->i_nlink) {
		nilfs_warning(inode->i_sb, __func__,
			      "deleting nonexistent file (%lu), %d\n",
			      inode->i_ino, inode->i_nlink);
		inode->i_nlink = 1;
	}
	err = nilfs_delete_entry(de, page);
	if (err)
		goto out;

	inode->i_ctime = dir->i_ctime;
	inode_dec_link_count(inode);
	err = 0;
out:
	if (!err)
		err = nilfs_transaction_commit(dir->i_sb);
	else
		nilfs_transaction_abort(dir->i_sb);

	return err;
}

static int nilfs_rmdir(struct inode *dir, struct dentry *dentry)
{
	struct inode *inode = dentry->d_inode;
	struct nilfs_transaction_info ti;
	int err;

	err = nilfs_transaction_begin(dir->i_sb, &ti, 0);
	if (err)
		return err;

	err = -ENOTEMPTY;
	if (nilfs_empty_dir(inode)) {
		err = nilfs_unlink(dir, dentry);
		if (!err) {
			inode->i_size = 0;
			inode_dec_link_count(inode);
			inode_dec_link_count(dir);
		}
	}
	if (!err)
		err = nilfs_transaction_commit(dir->i_sb);
	else
		nilfs_transaction_abort(dir->i_sb);

	return err;
}

static int nilfs_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 nilfs_dir_entry *dir_de = NULL;
	struct page *old_page;
	struct nilfs_dir_entry *old_de;
	struct nilfs_transaction_info ti;
	int err;

	err = nilfs_transaction_begin(old_dir->i_sb, &ti, 1);
	if (unlikely(err))
		return err;

	err = -ENOENT;
	old_de = nilfs_find_entry(old_dir, old_dentry, &old_page);
	if (!old_de)
		goto out;

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

	if (new_inode) {
		struct page *new_page;
		struct nilfs_dir_entry *new_de;

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

		err = -ENOENT;
		new_de = nilfs_find_entry(new_dir, new_dentry, &new_page);
		if (!new_de)
			goto out_dir;
		inode_inc_link_count(old_inode);
		nilfs_set_link(new_dir, new_de, new_page, old_inode);
		new_inode->i_ctime = CURRENT_TIME;
		if (dir_de)
			drop_nlink(new_inode);
		inode_dec_link_count(new_inode);
	} else {
		if (dir_de) {
			err = -EMLINK;
			if (new_dir->i_nlink >= NILFS_LINK_MAX)
				goto out_dir;
		}
		inode_inc_link_count(old_inode);
		err = nilfs_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;

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

	if (dir_de) {
		nilfs_set_link(old_inode, dir_de, dir_page, new_dir);
		inode_dec_link_count(old_dir);
	}

	err = nilfs_transaction_commit(old_dir->i_sb);
	return err;

out_dir:
	if (dir_de) {
		kunmap(dir_page);
		page_cache_release(dir_page);
	}
out_old:
	kunmap(old_page);
	page_cache_release(old_page);
out:
	nilfs_transaction_abort(old_dir->i_sb);
	return err;
}

struct inode_operations nilfs_dir_inode_operations = {
	.create		= nilfs_create,
	.lookup		= nilfs_lookup,
	.link		= nilfs_link,
	.unlink		= nilfs_unlink,
	.symlink	= nilfs_symlink,
	.mkdir		= nilfs_mkdir,
	.rmdir		= nilfs_rmdir,
	.mknod		= nilfs_mknod,
	.rename		= nilfs_rename,
	.setattr	= nilfs_setattr,
	.permission	= nilfs_permission,
};

struct inode_operations nilfs_special_inode_operations = {
	.setattr	= nilfs_setattr,
	.permission	= nilfs_permission,
};

struct inode_operations nilfs_symlink_inode_operations = {
	.readlink	= generic_readlink,
	.follow_link	= page_follow_link_light,
	.put_link	= page_put_link,
};
Commit	Line	Data
d2500652 RK	1	/*
	2	* namei.c - NILFS pathname lookup operations.
	3	*
	4	* Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License as published by
	8	* the Free Software Foundation; either version 2 of the License, or
	9	* (at your option) any later version.
	10	*
	11	* This program is distributed in the hope that it will be useful,
	12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	* GNU General Public License for more details.
	15	*
	16	* You should have received a copy of the GNU General Public License
	17	* along with this program; if not, write to the Free Software
	18	* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
	19	*
	20	* Modified for NILFS by Amagai Yoshiji <[email protected]>,
	21	* Ryusuke Konishi <[email protected]>
	22	*/
	23	/*
	24	* linux/fs/ext2/namei.c
	25	*
	26	* Copyright (C) 1992, 1993, 1994, 1995
	27	* Remy Card ([email protected])
	28	* Laboratoire MASI - Institut Blaise Pascal
	29	* Universite Pierre et Marie Curie (Paris VI)
	30	*
	31	* from
	32	*
	33	* linux/fs/minix/namei.c
	34	*
	35	* Copyright (C) 1991, 1992 Linus Torvalds
	36	*
	37	* Big-endian to little-endian byte-swapping/bitmaps by
	38	* David S. Miller ([email protected]), 1995
	39	*/
	40
	41	#include <linux/pagemap.h>
	42	#include "nilfs.h"
	43
	44
	45	static inline int nilfs_add_nondir(struct dentry dentry, struct inode inode)
	46	{
	47	int err = nilfs_add_link(dentry, inode);
	48	if (!err) {
	49	d_instantiate(dentry, inode);
	50	return 0;
	51	}
	52	inode_dec_link_count(inode);
	53	iput(inode);
	54	return err;
	55	}
	56
	57	/*
	58	* Methods themselves.
	59	*/
	60
	61	static struct dentry *
	62	nilfs_lookup(struct inode dir, struct dentry dentry, struct nameidata *nd)
	63	{
	64	struct inode *inode;
65	ino_t ino;
66
67	if (dentry->d_name.len > NILFS_NAME_LEN)
68	return ERR_PTR(-ENAMETOOLONG);
69
70	ino = nilfs_inode_by_name(dir, dentry);
71	inode = NULL;
72	if (ino) {
73	inode = nilfs_iget(dir->i_sb, ino);
74	if (IS_ERR(inode))
75	return ERR_CAST(inode);
76	}
77	return d_splice_alias(inode, dentry);
78	}
79
80	struct dentry nilfs_get_parent(struct dentry child)
81	{
82	unsigned long ino;
83	struct inode *inode;
84	struct dentry dotdot;
85
86	dotdot.d_name.name = "..";
87	dotdot.d_name.len = 2;
88
89	ino = nilfs_inode_by_name(child->d_inode, &dotdot);
90	if (!ino)
91	return ERR_PTR(-ENOENT);
92
93	inode = nilfs_iget(child->d_inode->i_sb, ino);
94	if (IS_ERR(inode))
95	return ERR_CAST(inode);
96	return d_obtain_alias(inode);
97	}
98
99	/*
100	* By the time this is called, we already have created
101	* the directory cache entry for the new file, but it
102	* is so far negative - it has no inode.
103	*
104	* If the create succeeds, we fill in the inode information
105	* with d_instantiate().
106	*/
107	static int nilfs_create(struct inode dir, struct dentry dentry, int mode,
108	struct nameidata *nd)
109	{
110	struct inode *inode;
111	struct nilfs_transaction_info ti;
47420c79	112	int err;
d2500652 RK	113
	114	err = nilfs_transaction_begin(dir->i_sb, &ti, 1);
	115	if (err)
	116	return err;
	117	inode = nilfs_new_inode(dir, mode);
	118	err = PTR_ERR(inode);
	119	if (!IS_ERR(inode)) {
	120	inode->i_op = &nilfs_file_inode_operations;
	121	inode->i_fop = &nilfs_file_operations;
	122	inode->i_mapping->a_ops = &nilfs_aops;
	123	mark_inode_dirty(inode);
	124	err = nilfs_add_nondir(dentry, inode);
	125	}
47420c79 RK	126	if (!err)
	127	err = nilfs_transaction_commit(dir->i_sb);
	128	else
	129	nilfs_transaction_abort(dir->i_sb);
	130
	131	return err;
d2500652 RK	132	}
	133
	134	static int
	135	nilfs_mknod(struct inode dir, struct dentry dentry, int mode, dev_t rdev)
	136	{
	137	struct inode *inode;
	138	struct nilfs_transaction_info ti;
47420c79	139	int err;
d2500652 RK	140
	141	if (!new_valid_dev(rdev))
	142	return -EINVAL;
	143
	144	err = nilfs_transaction_begin(dir->i_sb, &ti, 1);
	145	if (err)
	146	return err;
	147	inode = nilfs_new_inode(dir, mode);
	148	err = PTR_ERR(inode);
	149	if (!IS_ERR(inode)) {
	150	init_special_inode(inode, inode->i_mode, rdev);
	151	mark_inode_dirty(inode);
	152	err = nilfs_add_nondir(dentry, inode);
	153	}
47420c79 RK	154	if (!err)
	155	err = nilfs_transaction_commit(dir->i_sb);
	156	else
	157	nilfs_transaction_abort(dir->i_sb);
	158
	159	return err;
d2500652 RK	160	}
	161
	162	static int nilfs_symlink(struct inode dir, struct dentry dentry,
	163	const char *symname)
	164	{
	165	struct nilfs_transaction_info ti;
	166	struct super_block *sb = dir->i_sb;
	167	unsigned l = strlen(symname)+1;
	168	struct inode *inode;
47420c79	169	int err;
d2500652 RK	170
	171	if (l > sb->s_blocksize)
	172	return -ENAMETOOLONG;
	173
	174	err = nilfs_transaction_begin(dir->i_sb, &ti, 1);
	175	if (err)
	176	return err;
	177
	178	inode = nilfs_new_inode(dir, S_IFLNK \| S_IRWXUGO);
	179	err = PTR_ERR(inode);
	180	if (IS_ERR(inode))
	181	goto out;
	182
	183	/* slow symlink */
	184	inode->i_op = &nilfs_symlink_inode_operations;
	185	inode->i_mapping->a_ops = &nilfs_aops;
	186	err = page_symlink(inode, symname, l);
	187	if (err)
	188	goto out_fail;
	189
	190	/* mark_inode_dirty(inode); */
	191	/* nilfs_new_inode() and page_symlink() do this */
	192
	193	err = nilfs_add_nondir(dentry, inode);
	194	out:
47420c79 RK	195	if (!err)
	196	err = nilfs_transaction_commit(dir->i_sb);
	197	else
	198	nilfs_transaction_abort(dir->i_sb);
	199
	200	return err;
d2500652 RK	201
	202	out_fail:
	203	inode_dec_link_count(inode);
	204	iput(inode);
	205	goto out;
	206	}
	207
	208	static int nilfs_link(struct dentry old_dentry, struct inode dir,
	209	struct dentry *dentry)
	210	{
	211	struct inode *inode = old_dentry->d_inode;
	212	struct nilfs_transaction_info ti;
47420c79	213	int err;
d2500652 RK	214
	215	if (inode->i_nlink >= NILFS_LINK_MAX)
	216	return -EMLINK;
	217
	218	err = nilfs_transaction_begin(dir->i_sb, &ti, 1);
	219	if (err)
	220	return err;
	221
	222	inode->i_ctime = CURRENT_TIME;
	223	inode_inc_link_count(inode);
	224	atomic_inc(&inode->i_count);
	225
	226	err = nilfs_add_nondir(dentry, inode);
47420c79 RK	227	if (!err)
	228	err = nilfs_transaction_commit(dir->i_sb);
	229	else
	230	nilfs_transaction_abort(dir->i_sb);
	231
	232	return err;
d2500652 RK	233	}
	234
	235	static int nilfs_mkdir(struct inode dir, struct dentry dentry, int mode)
	236	{
	237	struct inode *inode;
	238	struct nilfs_transaction_info ti;
47420c79	239	int err;
d2500652 RK	240
	241	if (dir->i_nlink >= NILFS_LINK_MAX)
	242	return -EMLINK;
	243
	244	err = nilfs_transaction_begin(dir->i_sb, &ti, 1);
	245	if (err)
	246	return err;
	247
	248	inode_inc_link_count(dir);
	249
	250	inode = nilfs_new_inode(dir, S_IFDIR \| mode);
	251	err = PTR_ERR(inode);
	252	if (IS_ERR(inode))
	253	goto out_dir;
	254
	255	inode->i_op = &nilfs_dir_inode_operations;
	256	inode->i_fop = &nilfs_dir_operations;
	257	inode->i_mapping->a_ops = &nilfs_aops;
	258
	259	inode_inc_link_count(inode);
	260
	261	err = nilfs_make_empty(inode, dir);
	262	if (err)
	263	goto out_fail;
	264
	265	err = nilfs_add_link(dentry, inode);
	266	if (err)
	267	goto out_fail;
	268
	269	d_instantiate(dentry, inode);
	270	out:
47420c79 RK	271	if (!err)
	272	err = nilfs_transaction_commit(dir->i_sb);
	273	else
	274	nilfs_transaction_abort(dir->i_sb);
	275
	276	return err;
d2500652 RK	277
	278	out_fail:
	279	inode_dec_link_count(inode);
	280	inode_dec_link_count(inode);
	281	iput(inode);
	282	out_dir:
	283	inode_dec_link_count(dir);
	284	goto out;
	285	}
	286
	287	static int nilfs_unlink(struct inode dir, struct dentry dentry)
	288	{
	289	struct inode *inode;
	290	struct nilfs_dir_entry *de;
	291	struct page *page;
	292	struct nilfs_transaction_info ti;
47420c79	293	int err;
d2500652 RK	294
	295	err = nilfs_transaction_begin(dir->i_sb, &ti, 0);
	296	if (err)
	297	return err;
	298
	299	err = -ENOENT;
	300	de = nilfs_find_entry(dir, dentry, &page);
	301	if (!de)
	302	goto out;
	303
	304	inode = dentry->d_inode;
	305	err = -EIO;
	306	if (le64_to_cpu(de->inode) != inode->i_ino)
	307	goto out;
	308
	309	if (!inode->i_nlink) {
	310	nilfs_warning(inode->i_sb, __func__,
	311	"deleting nonexistent file (%lu), %d\n",
	312	inode->i_ino, inode->i_nlink);
	313	inode->i_nlink = 1;
	314	}
	315	err = nilfs_delete_entry(de, page);
	316	if (err)
	317	goto out;
	318
	319	inode->i_ctime = dir->i_ctime;
	320	inode_dec_link_count(inode);
	321	err = 0;
	322	out:
47420c79 RK	323	if (!err)
	324	err = nilfs_transaction_commit(dir->i_sb);
	325	else
	326	nilfs_transaction_abort(dir->i_sb);
	327
	328	return err;
d2500652 RK	329	}
	330
	331	static int nilfs_rmdir(struct inode dir, struct dentry dentry)
	332	{
	333	struct inode *inode = dentry->d_inode;
	334	struct nilfs_transaction_info ti;
47420c79	335	int err;
d2500652 RK	336
	337	err = nilfs_transaction_begin(dir->i_sb, &ti, 0);
	338	if (err)
	339	return err;
	340
	341	err = -ENOTEMPTY;
	342	if (nilfs_empty_dir(inode)) {
	343	err = nilfs_unlink(dir, dentry);
	344	if (!err) {
	345	inode->i_size = 0;
	346	inode_dec_link_count(inode);
	347	inode_dec_link_count(dir);
	348	}
	349	}
47420c79 RK	350	if (!err)
	351	err = nilfs_transaction_commit(dir->i_sb);
	352	else
	353	nilfs_transaction_abort(dir->i_sb);
	354
	355	return err;
d2500652 RK	356	}
	357
	358	static int nilfs_rename(struct inode old_dir, struct dentry old_dentry,
	359	struct inode new_dir, struct dentry new_dentry)
	360	{
	361	struct inode *old_inode = old_dentry->d_inode;
	362	struct inode *new_inode = new_dentry->d_inode;
	363	struct page *dir_page = NULL;
	364	struct nilfs_dir_entry *dir_de = NULL;
	365	struct page *old_page;
	366	struct nilfs_dir_entry *old_de;
	367	struct nilfs_transaction_info ti;
	368	int err;
	369
	370	err = nilfs_transaction_begin(old_dir->i_sb, &ti, 1);
	371	if (unlikely(err))
	372	return err;
	373
	374	err = -ENOENT;
	375	old_de = nilfs_find_entry(old_dir, old_dentry, &old_page);
	376	if (!old_de)
	377	goto out;
	378
	379	if (S_ISDIR(old_inode->i_mode)) {
	380	err = -EIO;
	381	dir_de = nilfs_dotdot(old_inode, &dir_page);
	382	if (!dir_de)
	383	goto out_old;
	384	}
	385
	386	if (new_inode) {
	387	struct page *new_page;
	388	struct nilfs_dir_entry *new_de;
	389
	390	err = -ENOTEMPTY;
	391	if (dir_de && !nilfs_empty_dir(new_inode))
	392	goto out_dir;
	393
	394	err = -ENOENT;
	395	new_de = nilfs_find_entry(new_dir, new_dentry, &new_page);
	396	if (!new_de)
	397	goto out_dir;
	398	inode_inc_link_count(old_inode);
	399	nilfs_set_link(new_dir, new_de, new_page, old_inode);
	400	new_inode->i_ctime = CURRENT_TIME;
	401	if (dir_de)
	402	drop_nlink(new_inode);
	403	inode_dec_link_count(new_inode);
	404	} else {
	405	if (dir_de) {
	406	err = -EMLINK;
	407	if (new_dir->i_nlink >= NILFS_LINK_MAX)
	408	goto out_dir;
	409	}
	410	inode_inc_link_count(old_inode);
	411	err = nilfs_add_link(new_dentry, old_inode);
	412	if (err) {
	413	inode_dec_link_count(old_inode);
	414	goto out_dir;
	415	}
	416	if (dir_de)
	417	inode_inc_link_count(new_dir);
	418	}
	419
420	/*
421	* Like most other Unix systems, set the ctime for inodes on a
422	* rename.
423	* inode_dec_link_count() will mark the inode dirty.
424	*/
425	old_inode->i_ctime = CURRENT_TIME;
426
427	nilfs_delete_entry(old_de, old_page);
428	inode_dec_link_count(old_inode);
429
430	if (dir_de) {
431	nilfs_set_link(old_inode, dir_de, dir_page, new_dir);
432	inode_dec_link_count(old_dir);
433	}
434
47420c79	435	err = nilfs_transaction_commit(old_dir->i_sb);
d2500652 RK	436	return err;
	437
	438	out_dir:
	439	if (dir_de) {
	440	kunmap(dir_page);
	441	page_cache_release(dir_page);
	442	}
	443	out_old:
	444	kunmap(old_page);
	445	page_cache_release(old_page);
	446	out:
47420c79	447	nilfs_transaction_abort(old_dir->i_sb);
d2500652 RK	448	return err;
	449	}
	450
	451	struct inode_operations nilfs_dir_inode_operations = {
	452	.create = nilfs_create,
	453	.lookup = nilfs_lookup,
	454	.link = nilfs_link,
	455	.unlink = nilfs_unlink,
	456	.symlink = nilfs_symlink,
	457	.mkdir = nilfs_mkdir,
	458	.rmdir = nilfs_rmdir,
	459	.mknod = nilfs_mknod,
	460	.rename = nilfs_rename,
	461	.setattr = nilfs_setattr,
	462	.permission = nilfs_permission,
	463	};
	464
	465	struct inode_operations nilfs_special_inode_operations = {
	466	.setattr = nilfs_setattr,
	467	.permission = nilfs_permission,
	468	};
	469
	470	struct inode_operations nilfs_symlink_inode_operations = {
	471	.readlink = generic_readlink,
	472	.follow_link = page_follow_link_light,
	473	.put_link = page_put_link,
	474	};