[mirror_ubuntu-artful-kernel.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 <amagai@osrg.net>,
 *                       Ryusuke Konishi <ryusuke@osrg.net>
 */
/*
 *  linux/fs/ext2/namei.c
 *
 * 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 "nilfs.h"
#include "export.h"

#define NILFS_FID_SIZE_NON_CONNECTABLE \
	(offsetof(struct nilfs_fid, parent_gen) / 4)
#define NILFS_FID_SIZE_CONNECTABLE	(sizeof(struct nilfs_fid) / 4)

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, unsigned int flags)
{
	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->d_name);
	inode = ino ? nilfs_iget(dir->i_sb, NILFS_I(dir)->i_root, ino) : NULL;
	return d_splice_alias(inode, dentry);
}

/*
 * 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, umode_t mode,
			bool excl)
{
	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;
		nilfs_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, umode_t 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);
		nilfs_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); */
	/* 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:
	drop_nlink(inode);
	nilfs_mark_inode_dirty(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;

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

	inode->i_ctime = CURRENT_TIME;
	inode_inc_link_count(inode);
	ihold(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_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
{
	struct inode *inode;
	struct nilfs_transaction_info ti;
	int err;

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

	inc_nlink(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;

	inc_nlink(inode);

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

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

	nilfs_mark_inode_dirty(inode);
	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:
	drop_nlink(inode);
	drop_nlink(inode);
	nilfs_mark_inode_dirty(inode);
	iput(inode);
out_dir:
	drop_nlink(dir);
	nilfs_mark_inode_dirty(dir);
	goto out;
}

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

	err = -ENOENT;
	de = nilfs_find_entry(dir, &dentry->d_name, &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);
		set_nlink(inode, 1);
	}
	err = nilfs_delete_entry(de, page);
	if (err)
		goto out;

	inode->i_ctime = dir->i_ctime;
	drop_nlink(inode);
	err = 0;
out:
	return err;
}

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

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

	err = nilfs_do_unlink(dir, dentry);

	if (!err) {
		nilfs_mark_inode_dirty(dir);
		nilfs_mark_inode_dirty(dentry->d_inode);
		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_do_unlink(dir, dentry);
		if (!err) {
			inode->i_size = 0;
			drop_nlink(inode);
			nilfs_mark_inode_dirty(inode);
			drop_nlink(dir);
			nilfs_mark_inode_dirty(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->d_name, &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->d_name, &new_page);
		if (!new_de)
			goto out_dir;
		nilfs_set_link(new_dir, new_de, new_page, old_inode);
		nilfs_mark_inode_dirty(new_dir);
		new_inode->i_ctime = CURRENT_TIME;
		if (dir_de)
			drop_nlink(new_inode);
		drop_nlink(new_inode);
		nilfs_mark_inode_dirty(new_inode);
	} else {
		err = nilfs_add_link(new_dentry, old_inode);
		if (err)
			goto out_dir;
		if (dir_de) {
			inc_nlink(new_dir);
			nilfs_mark_inode_dirty(new_dir);
		}
	}

	/*
	 * Like most other Unix systems, set the ctime for inodes on a
	 * rename.
	 */
	old_inode->i_ctime = CURRENT_TIME;

	nilfs_delete_entry(old_de, old_page);

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

	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;
}

/*
 * Export operations
 */
static struct dentry *nilfs_get_parent(struct dentry *child)
{
	unsigned long ino;
	struct inode *inode;
	struct qstr dotdot = QSTR_INIT("..", 2);
	struct nilfs_root *root;

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

	root = NILFS_I(child->d_inode)->i_root;

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

	return d_obtain_alias(inode);
}

static struct dentry *nilfs_get_dentry(struct super_block *sb, u64 cno,
				       u64 ino, u32 gen)
{
	struct nilfs_root *root;
	struct inode *inode;

	if (ino < NILFS_FIRST_INO(sb) && ino != NILFS_ROOT_INO)
		return ERR_PTR(-ESTALE);

	root = nilfs_lookup_root(sb->s_fs_info, cno);
	if (!root)
		return ERR_PTR(-ESTALE);

	inode = nilfs_iget(sb, root, ino);
	nilfs_put_root(root);

	if (IS_ERR(inode))
		return ERR_CAST(inode);
	if (gen && inode->i_generation != gen) {
		iput(inode);
		return ERR_PTR(-ESTALE);
	}
	return d_obtain_alias(inode);
}

static struct dentry *nilfs_fh_to_dentry(struct super_block *sb, struct fid *fh,
					 int fh_len, int fh_type)
{
	struct nilfs_fid *fid = (struct nilfs_fid *)fh;

	if ((fh_len != NILFS_FID_SIZE_NON_CONNECTABLE &&
	     fh_len != NILFS_FID_SIZE_CONNECTABLE) ||
	    (fh_type != FILEID_NILFS_WITH_PARENT &&
	     fh_type != FILEID_NILFS_WITHOUT_PARENT))
		return NULL;

	return nilfs_get_dentry(sb, fid->cno, fid->ino, fid->gen);
}

static struct dentry *nilfs_fh_to_parent(struct super_block *sb, struct fid *fh,
					 int fh_len, int fh_type)
{
	struct nilfs_fid *fid = (struct nilfs_fid *)fh;

	if (fh_len != NILFS_FID_SIZE_CONNECTABLE ||
	    fh_type != FILEID_NILFS_WITH_PARENT)
		return NULL;

	return nilfs_get_dentry(sb, fid->cno, fid->parent_ino, fid->parent_gen);
}

static int nilfs_encode_fh(struct inode *inode, __u32 *fh, int *lenp,
			   struct inode *parent)
{
	struct nilfs_fid *fid = (struct nilfs_fid *)fh;
	struct nilfs_root *root = NILFS_I(inode)->i_root;
	int type;

	if (parent && *lenp < NILFS_FID_SIZE_CONNECTABLE) {
		*lenp = NILFS_FID_SIZE_CONNECTABLE;
		return 255;
	}
	if (*lenp < NILFS_FID_SIZE_NON_CONNECTABLE) {
		*lenp = NILFS_FID_SIZE_NON_CONNECTABLE;
		return 255;
	}

	fid->cno = root->cno;
	fid->ino = inode->i_ino;
	fid->gen = inode->i_generation;

	if (parent) {
		fid->parent_ino = parent->i_ino;
		fid->parent_gen = parent->i_generation;
		type = FILEID_NILFS_WITH_PARENT;
		*lenp = NILFS_FID_SIZE_CONNECTABLE;
	} else {
		type = FILEID_NILFS_WITHOUT_PARENT;
		*lenp = NILFS_FID_SIZE_NON_CONNECTABLE;
	}

	return type;
}

const 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,
	.fiemap		= nilfs_fiemap,
};

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

const struct inode_operations nilfs_symlink_inode_operations = {
	.readlink	= generic_readlink,
	.follow_link	= page_follow_link_light,
	.put_link	= page_put_link,
	.permission     = nilfs_permission,
};

const struct export_operations nilfs_export_ops = {
	.encode_fh = nilfs_encode_fh,
	.fh_to_dentry = nilfs_fh_to_dentry,
	.fh_to_parent = nilfs_fh_to_parent,
	.get_parent = nilfs_get_parent,
};
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 <amagai@osrg.net>,
	21	* Ryusuke Konishi <ryusuke@osrg.net>
	22	*/
	23	/*
	24	* linux/fs/ext2/namei.c
	25	*
	26	* Copyright (C) 1992, 1993, 1994, 1995
	27	* Remy Card (card@masi.ibp.fr)
	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 (davem@caip.rutgers.edu), 1995
	39	*/
	40
	41	#include <linux/pagemap.h>
	42	#include "nilfs.h"
8e656fd5	43	#include "export.h"
d2500652	44
8e656fd5 RK	45	#define NILFS_FID_SIZE_NON_CONNECTABLE \
	46	(offsetof(struct nilfs_fid, parent_gen) / 4)
	47	#define NILFS_FID_SIZE_CONNECTABLE (sizeof(struct nilfs_fid) / 4)
d2500652 RK	48
	49	static inline int nilfs_add_nondir(struct dentry dentry, struct inode inode)
	50	{
	51	int err = nilfs_add_link(dentry, inode);
	52	if (!err) {
	53	d_instantiate(dentry, inode);
	54	return 0;
	55	}
	56	inode_dec_link_count(inode);
	57	iput(inode);
	58	return err;
	59	}
	60
	61	/*
	62	* Methods themselves.
	63	*/
	64
	65	static struct dentry *
00cd8dd3	66	nilfs_lookup(struct inode dir, struct dentry dentry, unsigned int flags)
d2500652 RK	67	{
	68	struct inode *inode;
	69	ino_t ino;
	70
	71	if (dentry->d_name.len > NILFS_NAME_LEN)
	72	return ERR_PTR(-ENAMETOOLONG);
	73
0319003d	74	ino = nilfs_inode_by_name(dir, &dentry->d_name);
a9049376	75	inode = ino ? nilfs_iget(dir->i_sb, NILFS_I(dir)->i_root, ino) : NULL;
d2500652 RK	76	return d_splice_alias(inode, dentry);
	77	}
	78
d2500652 RK	79	/*
	80	* By the time this is called, we already have created
	81	* the directory cache entry for the new file, but it
	82	* is so far negative - it has no inode.
	83	*
	84	* If the create succeeds, we fill in the inode information
	85	* with d_instantiate().
	86	*/
4acdaf27	87	static int nilfs_create(struct inode dir, struct dentry dentry, umode_t mode,
ebfc3b49	88	bool excl)
d2500652 RK	89	{
	90	struct inode *inode;
	91	struct nilfs_transaction_info ti;
47420c79	92	int err;
d2500652 RK	93
	94	err = nilfs_transaction_begin(dir->i_sb, &ti, 1);
	95	if (err)
	96	return err;
	97	inode = nilfs_new_inode(dir, mode);
	98	err = PTR_ERR(inode);
	99	if (!IS_ERR(inode)) {
	100	inode->i_op = &nilfs_file_inode_operations;
	101	inode->i_fop = &nilfs_file_operations;
	102	inode->i_mapping->a_ops = &nilfs_aops;
abdb318b	103	nilfs_mark_inode_dirty(inode);
d2500652 RK	104	err = nilfs_add_nondir(dentry, inode);
d2500652 RK	105	}
47420c79 RK	106	if (!err)
	107	err = nilfs_transaction_commit(dir->i_sb);
	108	else
	109	nilfs_transaction_abort(dir->i_sb);
	110
	111	return err;
d2500652 RK	112	}
	113
	114	static int
1a67aafb	115	nilfs_mknod(struct inode dir, struct dentry dentry, umode_t mode, dev_t rdev)
d2500652 RK	116	{
	117	struct inode *inode;
	118	struct nilfs_transaction_info ti;
47420c79	119	int err;
d2500652 RK	120
	121	if (!new_valid_dev(rdev))
	122	return -EINVAL;
	123
	124	err = nilfs_transaction_begin(dir->i_sb, &ti, 1);
	125	if (err)
	126	return err;
	127	inode = nilfs_new_inode(dir, mode);
	128	err = PTR_ERR(inode);
	129	if (!IS_ERR(inode)) {
	130	init_special_inode(inode, inode->i_mode, rdev);
abdb318b	131	nilfs_mark_inode_dirty(inode);
d2500652 RK	132	err = nilfs_add_nondir(dentry, inode);
d2500652 RK	133	}
47420c79 RK	134	if (!err)
	135	err = nilfs_transaction_commit(dir->i_sb);
	136	else
	137	nilfs_transaction_abort(dir->i_sb);
	138
	139	return err;
d2500652 RK	140	}
	141
	142	static int nilfs_symlink(struct inode dir, struct dentry dentry,
	143	const char *symname)
	144	{
	145	struct nilfs_transaction_info ti;
	146	struct super_block *sb = dir->i_sb;
	147	unsigned l = strlen(symname)+1;
	148	struct inode *inode;
47420c79	149	int err;
d2500652 RK	150
	151	if (l > sb->s_blocksize)
	152	return -ENAMETOOLONG;
	153
	154	err = nilfs_transaction_begin(dir->i_sb, &ti, 1);
	155	if (err)
	156	return err;
	157
	158	inode = nilfs_new_inode(dir, S_IFLNK \| S_IRWXUGO);
	159	err = PTR_ERR(inode);
	160	if (IS_ERR(inode))
	161	goto out;
	162
	163	/* slow symlink */
	164	inode->i_op = &nilfs_symlink_inode_operations;
	165	inode->i_mapping->a_ops = &nilfs_aops;
	166	err = page_symlink(inode, symname, l);
	167	if (err)
	168	goto out_fail;
	169
	170	/* mark_inode_dirty(inode); */
9ca941d4	171	/* page_symlink() do this */
d2500652 RK	172
	173	err = nilfs_add_nondir(dentry, inode);
	174	out:
47420c79 RK	175	if (!err)
	176	err = nilfs_transaction_commit(dir->i_sb);
	177	else
	178	nilfs_transaction_abort(dir->i_sb);
	179
	180	return err;
d2500652 RK	181
d2500652 RK	182	out_fail:
565de406	183	drop_nlink(inode);
abdb318b	184	nilfs_mark_inode_dirty(inode);
d2500652 RK	185	iput(inode);
	186	goto out;
	187	}
	188
	189	static int nilfs_link(struct dentry old_dentry, struct inode dir,
	190	struct dentry *dentry)
	191	{
	192	struct inode *inode = old_dentry->d_inode;
	193	struct nilfs_transaction_info ti;
47420c79	194	int err;
d2500652	195
d2500652 RK	196	err = nilfs_transaction_begin(dir->i_sb, &ti, 1);
	197	if (err)
	198	return err;
	199
	200	inode->i_ctime = CURRENT_TIME;
	201	inode_inc_link_count(inode);
7de9c6ee	202	ihold(inode);
d2500652 RK	203
d2500652 RK	204	err = nilfs_add_nondir(dentry, inode);
47420c79 RK	205	if (!err)
	206	err = nilfs_transaction_commit(dir->i_sb);
	207	else
	208	nilfs_transaction_abort(dir->i_sb);
	209
	210	return err;
d2500652 RK	211	}
d2500652 RK	212
18bb1db3	213	static int nilfs_mkdir(struct inode dir, struct dentry dentry, umode_t mode)
d2500652 RK	214	{
	215	struct inode *inode;
	216	struct nilfs_transaction_info ti;
47420c79	217	int err;
d2500652	218
d2500652 RK	219	err = nilfs_transaction_begin(dir->i_sb, &ti, 1);
	220	if (err)
	221	return err;
	222
565de406	223	inc_nlink(dir);
d2500652 RK	224
	225	inode = nilfs_new_inode(dir, S_IFDIR \| mode);
	226	err = PTR_ERR(inode);
	227	if (IS_ERR(inode))
	228	goto out_dir;
	229
	230	inode->i_op = &nilfs_dir_inode_operations;
	231	inode->i_fop = &nilfs_dir_operations;
	232	inode->i_mapping->a_ops = &nilfs_aops;
	233
565de406	234	inc_nlink(inode);
d2500652 RK	235
	236	err = nilfs_make_empty(inode, dir);
	237	if (err)
	238	goto out_fail;
	239
	240	err = nilfs_add_link(dentry, inode);
	241	if (err)
	242	goto out_fail;
	243
abdb318b	244	nilfs_mark_inode_dirty(inode);
d2500652 RK	245	d_instantiate(dentry, inode);
d2500652 RK	246	out:
47420c79 RK	247	if (!err)
	248	err = nilfs_transaction_commit(dir->i_sb);
	249	else
	250	nilfs_transaction_abort(dir->i_sb);
	251
	252	return err;
d2500652 RK	253
d2500652 RK	254	out_fail:
565de406	255	drop_nlink(inode);
565de406	256	drop_nlink(inode);
abdb318b	257	nilfs_mark_inode_dirty(inode);
d2500652 RK	258	iput(inode);
d2500652 RK	259	out_dir:
565de406	260	drop_nlink(dir);
abdb318b	261	nilfs_mark_inode_dirty(dir);
d2500652 RK	262	goto out;
	263	}
	264
4cd76c3c	265	static int nilfs_do_unlink(struct inode dir, struct dentry dentry)
d2500652 RK	266	{
	267	struct inode *inode;
	268	struct nilfs_dir_entry *de;
	269	struct page *page;
47420c79	270	int err;
d2500652	271
d2500652	272	err = -ENOENT;
0319003d	273	de = nilfs_find_entry(dir, &dentry->d_name, &page);
d2500652 RK	274	if (!de)
	275	goto out;
	276
	277	inode = dentry->d_inode;
	278	err = -EIO;
	279	if (le64_to_cpu(de->inode) != inode->i_ino)
	280	goto out;
	281
	282	if (!inode->i_nlink) {
	283	nilfs_warning(inode->i_sb, __func__,
	284	"deleting nonexistent file (%lu), %d\n",
	285	inode->i_ino, inode->i_nlink);
bfe86848	286	set_nlink(inode, 1);
d2500652 RK	287	}
	288	err = nilfs_delete_entry(de, page);
	289	if (err)
	290	goto out;
	291
	292	inode->i_ctime = dir->i_ctime;
565de406	293	drop_nlink(inode);
d2500652 RK	294	err = 0;
d2500652 RK	295	out:
4cd76c3c JS	296	return err;
	297	}
	298
	299	static int nilfs_unlink(struct inode dir, struct dentry dentry)
	300	{
	301	struct nilfs_transaction_info ti;
	302	int err;
	303
	304	err = nilfs_transaction_begin(dir->i_sb, &ti, 0);
	305	if (err)
	306	return err;
	307
	308	err = nilfs_do_unlink(dir, dentry);
	309
	310	if (!err) {
abdb318b JS	311	nilfs_mark_inode_dirty(dir);
abdb318b JS	312	nilfs_mark_inode_dirty(dentry->d_inode);
47420c79	313	err = nilfs_transaction_commit(dir->i_sb);
4cd76c3c	314	} else
47420c79 RK	315	nilfs_transaction_abort(dir->i_sb);
	316
	317	return err;
d2500652 RK	318	}
	319
	320	static int nilfs_rmdir(struct inode dir, struct dentry dentry)
	321	{
	322	struct inode *inode = dentry->d_inode;
	323	struct nilfs_transaction_info ti;
47420c79	324	int err;
d2500652 RK	325
	326	err = nilfs_transaction_begin(dir->i_sb, &ti, 0);
	327	if (err)
	328	return err;
	329
	330	err = -ENOTEMPTY;
	331	if (nilfs_empty_dir(inode)) {
4cd76c3c	332	err = nilfs_do_unlink(dir, dentry);
d2500652 RK	333	if (!err) {
d2500652 RK	334	inode->i_size = 0;
565de406	335	drop_nlink(inode);
abdb318b	336	nilfs_mark_inode_dirty(inode);
565de406	337	drop_nlink(dir);
abdb318b	338	nilfs_mark_inode_dirty(dir);
d2500652 RK	339	}
d2500652 RK	340	}
47420c79 RK	341	if (!err)
	342	err = nilfs_transaction_commit(dir->i_sb);
	343	else
	344	nilfs_transaction_abort(dir->i_sb);
	345
	346	return err;
d2500652 RK	347	}
	348
	349	static int nilfs_rename(struct inode old_dir, struct dentry old_dentry,
	350	struct inode new_dir, struct dentry new_dentry)
	351	{
	352	struct inode *old_inode = old_dentry->d_inode;
	353	struct inode *new_inode = new_dentry->d_inode;
	354	struct page *dir_page = NULL;
	355	struct nilfs_dir_entry *dir_de = NULL;
	356	struct page *old_page;
	357	struct nilfs_dir_entry *old_de;
	358	struct nilfs_transaction_info ti;
	359	int err;
	360
	361	err = nilfs_transaction_begin(old_dir->i_sb, &ti, 1);
	362	if (unlikely(err))
	363	return err;
	364
	365	err = -ENOENT;
0319003d	366	old_de = nilfs_find_entry(old_dir, &old_dentry->d_name, &old_page);
d2500652 RK	367	if (!old_de)
	368	goto out;
	369
	370	if (S_ISDIR(old_inode->i_mode)) {
	371	err = -EIO;
	372	dir_de = nilfs_dotdot(old_inode, &dir_page);
	373	if (!dir_de)
	374	goto out_old;
	375	}
	376
	377	if (new_inode) {
	378	struct page *new_page;
	379	struct nilfs_dir_entry *new_de;
	380
	381	err = -ENOTEMPTY;
	382	if (dir_de && !nilfs_empty_dir(new_inode))
	383	goto out_dir;
	384
	385	err = -ENOENT;
0319003d	386	new_de = nilfs_find_entry(new_dir, &new_dentry->d_name, &new_page);
d2500652 RK	387	if (!new_de)
d2500652 RK	388	goto out_dir;
d2500652	389	nilfs_set_link(new_dir, new_de, new_page, old_inode);
abdb318b	390	nilfs_mark_inode_dirty(new_dir);
d2500652 RK	391	new_inode->i_ctime = CURRENT_TIME;
	392	if (dir_de)
	393	drop_nlink(new_inode);
565de406	394	drop_nlink(new_inode);
abdb318b	395	nilfs_mark_inode_dirty(new_inode);
d2500652	396	} else {
d2500652	397	err = nilfs_add_link(new_dentry, old_inode);
30eb43d3	398	if (err)
d2500652	399	goto out_dir;
565de406 JS	400	if (dir_de) {
565de406 JS	401	inc_nlink(new_dir);
abdb318b	402	nilfs_mark_inode_dirty(new_dir);
565de406	403	}
d2500652 RK	404	}
	405
	406	/*
	407	* Like most other Unix systems, set the ctime for inodes on a
	408	* rename.
d2500652 RK	409	*/
	410	old_inode->i_ctime = CURRENT_TIME;
	411
	412	nilfs_delete_entry(old_de, old_page);
d2500652 RK	413
	414	if (dir_de) {
	415	nilfs_set_link(old_inode, dir_de, dir_page, new_dir);
565de406	416	drop_nlink(old_dir);
d2500652	417	}
abdb318b JS	418	nilfs_mark_inode_dirty(old_dir);
abdb318b JS	419	nilfs_mark_inode_dirty(old_inode);
d2500652	420
47420c79	421	err = nilfs_transaction_commit(old_dir->i_sb);
d2500652 RK	422	return err;
	423
	424	out_dir:
	425	if (dir_de) {
	426	kunmap(dir_page);
	427	page_cache_release(dir_page);
	428	}
	429	out_old:
	430	kunmap(old_page);
	431	page_cache_release(old_page);
	432	out:
47420c79	433	nilfs_transaction_abort(old_dir->i_sb);
d2500652 RK	434	return err;
	435	}
	436
8e656fd5 RK	437	/*
	438	* Export operations
	439	*/
	440	static struct dentry nilfs_get_parent(struct dentry child)
	441	{
	442	unsigned long ino;
	443	struct inode *inode;
26fe5750	444	struct qstr dotdot = QSTR_INIT("..", 2);
8e656fd5 RK	445	struct nilfs_root *root;
	446
	447	ino = nilfs_inode_by_name(child->d_inode, &dotdot);
	448	if (!ino)
	449	return ERR_PTR(-ENOENT);
	450
	451	root = NILFS_I(child->d_inode)->i_root;
	452
	453	inode = nilfs_iget(child->d_inode->i_sb, root, ino);
	454	if (IS_ERR(inode))
	455	return ERR_CAST(inode);
	456
	457	return d_obtain_alias(inode);
	458	}
	459
	460	static struct dentry nilfs_get_dentry(struct super_block sb, u64 cno,
	461	u64 ino, u32 gen)
	462	{
	463	struct nilfs_root *root;
	464	struct inode *inode;
	465
	466	if (ino < NILFS_FIRST_INO(sb) && ino != NILFS_ROOT_INO)
	467	return ERR_PTR(-ESTALE);
	468
e3154e97	469	root = nilfs_lookup_root(sb->s_fs_info, cno);
8e656fd5 RK	470	if (!root)
	471	return ERR_PTR(-ESTALE);
	472
	473	inode = nilfs_iget(sb, root, ino);
	474	nilfs_put_root(root);
	475
	476	if (IS_ERR(inode))
	477	return ERR_CAST(inode);
	478	if (gen && inode->i_generation != gen) {
	479	iput(inode);
	480	return ERR_PTR(-ESTALE);
	481	}
	482	return d_obtain_alias(inode);
	483	}
	484
	485	static struct dentry nilfs_fh_to_dentry(struct super_block sb, struct fid *fh,
	486	int fh_len, int fh_type)
	487	{
	488	struct nilfs_fid fid = (struct nilfs_fid )fh;
	489
	490	if ((fh_len != NILFS_FID_SIZE_NON_CONNECTABLE &&
	491	fh_len != NILFS_FID_SIZE_CONNECTABLE) \|\|
	492	(fh_type != FILEID_NILFS_WITH_PARENT &&
	493	fh_type != FILEID_NILFS_WITHOUT_PARENT))
	494	return NULL;
	495
	496	return nilfs_get_dentry(sb, fid->cno, fid->ino, fid->gen);
	497	}
	498
	499	static struct dentry nilfs_fh_to_parent(struct super_block sb, struct fid *fh,
	500	int fh_len, int fh_type)
	501	{
	502	struct nilfs_fid fid = (struct nilfs_fid )fh;
	503
	504	if (fh_len != NILFS_FID_SIZE_CONNECTABLE \|\|
	505	fh_type != FILEID_NILFS_WITH_PARENT)
	506	return NULL;
	507
	508	return nilfs_get_dentry(sb, fid->cno, fid->parent_ino, fid->parent_gen);
	509	}
	510
b0b0382b AV	511	static int nilfs_encode_fh(struct inode inode, __u32 fh, int *lenp,
b0b0382b AV	512	struct inode *parent)
8e656fd5 RK	513	{
8e656fd5 RK	514	struct nilfs_fid fid = (struct nilfs_fid )fh;
8e656fd5 RK	515	struct nilfs_root *root = NILFS_I(inode)->i_root;
	516	int type;
	517
b0b0382b AV	518	if (parent && *lenp < NILFS_FID_SIZE_CONNECTABLE) {
	519	*lenp = NILFS_FID_SIZE_CONNECTABLE;
	520	return 255;
	521	}
	522	if (*lenp < NILFS_FID_SIZE_NON_CONNECTABLE) {
	523	*lenp = NILFS_FID_SIZE_NON_CONNECTABLE;
8e656fd5	524	return 255;
b0b0382b	525	}
8e656fd5 RK	526
	527	fid->cno = root->cno;
	528	fid->ino = inode->i_ino;
	529	fid->gen = inode->i_generation;
	530
b0b0382b	531	if (parent) {
8e656fd5 RK	532	fid->parent_ino = parent->i_ino;
8e656fd5 RK	533	fid->parent_gen = parent->i_generation;
8e656fd5 RK	534	type = FILEID_NILFS_WITH_PARENT;
	535	*lenp = NILFS_FID_SIZE_CONNECTABLE;
	536	} else {
	537	type = FILEID_NILFS_WITHOUT_PARENT;
	538	*lenp = NILFS_FID_SIZE_NON_CONNECTABLE;
	539	}
	540
	541	return type;
	542	}
	543
6e1d5dcc	544	const struct inode_operations nilfs_dir_inode_operations = {
d2500652 RK	545	.create = nilfs_create,
	546	.lookup = nilfs_lookup,
	547	.link = nilfs_link,
	548	.unlink = nilfs_unlink,
	549	.symlink = nilfs_symlink,
	550	.mkdir = nilfs_mkdir,
	551	.rmdir = nilfs_rmdir,
	552	.mknod = nilfs_mknod,
	553	.rename = nilfs_rename,
	554	.setattr = nilfs_setattr,
	555	.permission = nilfs_permission,
622daaff	556	.fiemap = nilfs_fiemap,
d2500652 RK	557	};
d2500652 RK	558
6e1d5dcc	559	const struct inode_operations nilfs_special_inode_operations = {
d2500652 RK	560	.setattr = nilfs_setattr,
	561	.permission = nilfs_permission,
	562	};
	563
6e1d5dcc	564	const struct inode_operations nilfs_symlink_inode_operations = {
d2500652 RK	565	.readlink = generic_readlink,
	566	.follow_link = page_follow_link_light,
	567	.put_link = page_put_link,
dc3d3b81	568	.permission = nilfs_permission,
d2500652	569	};
8e656fd5 RK	570
	571	const struct export_operations nilfs_export_ops = {
	572	.encode_fh = nilfs_encode_fh,
	573	.fh_to_dentry = nilfs_fh_to_dentry,
	574	.fh_to_parent = nilfs_fh_to_parent,
	575	.get_parent = nilfs_get_parent,
	576	};