[GitHub/LineageOS/android_kernel_motorola_exynos9610.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.
 *
 * Modified for NILFS by Amagai Yoshiji and Ryusuke Konishi.
 */
/*
 *  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_new(dentry, inode);
		return 0;
	}
	inode_dec_link_count(inode);
	unlock_new_inode(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;

	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 int 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_nohighmem(inode);
	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);
	unlock_new_inode(inode);
	iput(inode);
	goto out;
}

static int nilfs_link(struct dentry *old_dentry, struct inode *dir,
		      struct dentry *dentry)
{
	struct inode *inode = d_inode(old_dentry);
	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);
	inode_inc_link_count(inode);
	ihold(inode);

	err = nilfs_add_link(dentry, inode);
	if (!err) {
		d_instantiate(dentry, inode);
		err = nilfs_transaction_commit(dir->i_sb);
	} else {
		inode_dec_link_count(inode);
		iput(inode);
		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_new(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);
	unlock_new_inode(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 = d_inode(dentry);
	err = -EIO;
	if (le64_to_cpu(de->inode) != inode->i_ino)
		goto out;

	if (!inode->i_nlink) {
		nilfs_msg(inode->i_sb, KERN_WARNING,
			  "deleting nonexistent file (ino=%lu), %d",
			  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(d_inode(dentry));
		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 = d_inode(dentry);
	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,
			unsigned int flags)
{
	struct inode *old_inode = d_inode(old_dentry);
	struct inode *new_inode = d_inode(new_dentry);
	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;

	if (flags & ~RENAME_NOREPLACE)
		return -EINVAL;

	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(new_inode);
		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(old_inode);

	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);
		put_page(dir_page);
	}
out_old:
	kunmap(old_page);
	put_page(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(d_inode(child), &dotdot);
	if (!ino)
		return ERR_PTR(-ENOENT);

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

	inode = nilfs_iget(child->d_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_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 FILEID_INVALID;
	}
	if (*lenp < NILFS_FID_SIZE_NON_CONNECTABLE) {
		*lenp = NILFS_FID_SIZE_NON_CONNECTABLE;
		return FILEID_INVALID;
	}

	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 = {
	.get_link	= page_get_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
	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	* Modified for NILFS by Amagai Yoshiji and Ryusuke Konishi.
	17	*/
	18	/*
	19	* linux/fs/ext2/namei.c
	20	*
	21	* Copyright (C) 1992, 1993, 1994, 1995
	22	* Remy Card (card@masi.ibp.fr)
	23	* Laboratoire MASI - Institut Blaise Pascal
	24	* Universite Pierre et Marie Curie (Paris VI)
	25	*
	26	* from
	27	*
	28	* linux/fs/minix/namei.c
	29	*
	30	* Copyright (C) 1991, 1992 Linus Torvalds
	31	*
	32	* Big-endian to little-endian byte-swapping/bitmaps by
	33	* David S. Miller (davem@caip.rutgers.edu), 1995
	34	*/
	35
	36	#include <linux/pagemap.h>
	37	#include "nilfs.h"
	38	#include "export.h"
	39
	40	#define NILFS_FID_SIZE_NON_CONNECTABLE \
	41	(offsetof(struct nilfs_fid, parent_gen) / 4)
	42	#define NILFS_FID_SIZE_CONNECTABLE (sizeof(struct nilfs_fid) / 4)
	43
	44	static inline int nilfs_add_nondir(struct dentry dentry, struct inode inode)
	45	{
	46	int err = nilfs_add_link(dentry, inode);
	47
	48	if (!err) {
	49	d_instantiate_new(dentry, inode);
	50	return 0;
	51	}
	52	inode_dec_link_count(inode);
	53	unlock_new_inode(inode);
	54	iput(inode);
	55	return err;
	56	}
	57
	58	/*
	59	* Methods themselves.
	60	*/
	61
	62	static struct dentry *
	63	nilfs_lookup(struct inode dir, struct dentry dentry, unsigned int flags)
	64	{
	65	struct inode *inode;
	66	ino_t ino;
	67
	68	if (dentry->d_name.len > NILFS_NAME_LEN)
	69	return ERR_PTR(-ENAMETOOLONG);
	70
	71	ino = nilfs_inode_by_name(dir, &dentry->d_name);
	72	inode = ino ? nilfs_iget(dir->i_sb, NILFS_I(dir)->i_root, ino) : NULL;
	73	return d_splice_alias(inode, dentry);
	74	}
	75
	76	/*
	77	* By the time this is called, we already have created
	78	* the directory cache entry for the new file, but it
	79	* is so far negative - it has no inode.
	80	*
	81	* If the create succeeds, we fill in the inode information
	82	* with d_instantiate().
	83	*/
	84	static int nilfs_create(struct inode dir, struct dentry dentry, umode_t mode,
	85	bool excl)
	86	{
	87	struct inode *inode;
	88	struct nilfs_transaction_info ti;
	89	int err;
	90
	91	err = nilfs_transaction_begin(dir->i_sb, &ti, 1);
	92	if (err)
	93	return err;
	94	inode = nilfs_new_inode(dir, mode);
	95	err = PTR_ERR(inode);
	96	if (!IS_ERR(inode)) {
	97	inode->i_op = &nilfs_file_inode_operations;
	98	inode->i_fop = &nilfs_file_operations;
	99	inode->i_mapping->a_ops = &nilfs_aops;
	100	nilfs_mark_inode_dirty(inode);
	101	err = nilfs_add_nondir(dentry, inode);
	102	}
	103	if (!err)
	104	err = nilfs_transaction_commit(dir->i_sb);
	105	else
	106	nilfs_transaction_abort(dir->i_sb);
	107
	108	return err;
	109	}
	110
	111	static int
	112	nilfs_mknod(struct inode dir, struct dentry dentry, umode_t mode, dev_t rdev)
	113	{
	114	struct inode *inode;
	115	struct nilfs_transaction_info ti;
	116	int err;
	117
	118	err = nilfs_transaction_begin(dir->i_sb, &ti, 1);
	119	if (err)
	120	return err;
	121	inode = nilfs_new_inode(dir, mode);
	122	err = PTR_ERR(inode);
	123	if (!IS_ERR(inode)) {
	124	init_special_inode(inode, inode->i_mode, rdev);
	125	nilfs_mark_inode_dirty(inode);
	126	err = nilfs_add_nondir(dentry, inode);
	127	}
	128	if (!err)
	129	err = nilfs_transaction_commit(dir->i_sb);
	130	else
	131	nilfs_transaction_abort(dir->i_sb);
	132
	133	return err;
	134	}
	135
	136	static int nilfs_symlink(struct inode dir, struct dentry dentry,
	137	const char *symname)
	138	{
	139	struct nilfs_transaction_info ti;
	140	struct super_block *sb = dir->i_sb;
	141	unsigned int l = strlen(symname) + 1;
	142	struct inode *inode;
	143	int err;
	144
	145	if (l > sb->s_blocksize)
	146	return -ENAMETOOLONG;
	147
	148	err = nilfs_transaction_begin(dir->i_sb, &ti, 1);
	149	if (err)
	150	return err;
	151
	152	inode = nilfs_new_inode(dir, S_IFLNK \| S_IRWXUGO);
	153	err = PTR_ERR(inode);
	154	if (IS_ERR(inode))
	155	goto out;
	156
	157	/* slow symlink */
	158	inode->i_op = &nilfs_symlink_inode_operations;
	159	inode_nohighmem(inode);
	160	inode->i_mapping->a_ops = &nilfs_aops;
	161	err = page_symlink(inode, symname, l);
	162	if (err)
	163	goto out_fail;
	164
	165	/* mark_inode_dirty(inode); */
	166	/* page_symlink() do this */
	167
	168	err = nilfs_add_nondir(dentry, inode);
	169	out:
	170	if (!err)
	171	err = nilfs_transaction_commit(dir->i_sb);
	172	else
	173	nilfs_transaction_abort(dir->i_sb);
	174
	175	return err;
	176
	177	out_fail:
	178	drop_nlink(inode);
	179	nilfs_mark_inode_dirty(inode);
	180	unlock_new_inode(inode);
	181	iput(inode);
	182	goto out;
	183	}
	184
	185	static int nilfs_link(struct dentry old_dentry, struct inode dir,
	186	struct dentry *dentry)
	187	{
	188	struct inode *inode = d_inode(old_dentry);
	189	struct nilfs_transaction_info ti;
	190	int err;
	191
	192	err = nilfs_transaction_begin(dir->i_sb, &ti, 1);
	193	if (err)
	194	return err;
	195
	196	inode->i_ctime = current_time(inode);
	197	inode_inc_link_count(inode);
	198	ihold(inode);
	199
	200	err = nilfs_add_link(dentry, inode);
	201	if (!err) {
	202	d_instantiate(dentry, inode);
	203	err = nilfs_transaction_commit(dir->i_sb);
	204	} else {
	205	inode_dec_link_count(inode);
	206	iput(inode);
	207	nilfs_transaction_abort(dir->i_sb);
	208	}
	209
	210	return err;
	211	}
	212
	213	static int nilfs_mkdir(struct inode dir, struct dentry dentry, umode_t mode)
	214	{
	215	struct inode *inode;
	216	struct nilfs_transaction_info ti;
	217	int err;
	218
	219	err = nilfs_transaction_begin(dir->i_sb, &ti, 1);
	220	if (err)
	221	return err;
	222
	223	inc_nlink(dir);
	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
	234	inc_nlink(inode);
	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
	244	nilfs_mark_inode_dirty(inode);
	245	d_instantiate_new(dentry, inode);
	246	out:
	247	if (!err)
	248	err = nilfs_transaction_commit(dir->i_sb);
	249	else
	250	nilfs_transaction_abort(dir->i_sb);
	251
	252	return err;
	253
	254	out_fail:
	255	drop_nlink(inode);
	256	drop_nlink(inode);
	257	nilfs_mark_inode_dirty(inode);
	258	unlock_new_inode(inode);
	259	iput(inode);
	260	out_dir:
	261	drop_nlink(dir);
	262	nilfs_mark_inode_dirty(dir);
	263	goto out;
	264	}
	265
	266	static int nilfs_do_unlink(struct inode dir, struct dentry dentry)
	267	{
	268	struct inode *inode;
	269	struct nilfs_dir_entry *de;
	270	struct page *page;
	271	int err;
	272
	273	err = -ENOENT;
	274	de = nilfs_find_entry(dir, &dentry->d_name, &page);
	275	if (!de)
	276	goto out;
	277
	278	inode = d_inode(dentry);
	279	err = -EIO;
	280	if (le64_to_cpu(de->inode) != inode->i_ino)
	281	goto out;
	282
	283	if (!inode->i_nlink) {
	284	nilfs_msg(inode->i_sb, KERN_WARNING,
	285	"deleting nonexistent file (ino=%lu), %d",
	286	inode->i_ino, inode->i_nlink);
	287	set_nlink(inode, 1);
	288	}
	289	err = nilfs_delete_entry(de, page);
	290	if (err)
	291	goto out;
	292
	293	inode->i_ctime = dir->i_ctime;
	294	drop_nlink(inode);
	295	err = 0;
	296	out:
	297	return err;
	298	}
	299
	300	static int nilfs_unlink(struct inode dir, struct dentry dentry)
	301	{
	302	struct nilfs_transaction_info ti;
	303	int err;
	304
	305	err = nilfs_transaction_begin(dir->i_sb, &ti, 0);
	306	if (err)
	307	return err;
	308
	309	err = nilfs_do_unlink(dir, dentry);
	310
	311	if (!err) {
	312	nilfs_mark_inode_dirty(dir);
	313	nilfs_mark_inode_dirty(d_inode(dentry));
	314	err = nilfs_transaction_commit(dir->i_sb);
	315	} else
	316	nilfs_transaction_abort(dir->i_sb);
	317
	318	return err;
	319	}
	320
	321	static int nilfs_rmdir(struct inode dir, struct dentry dentry)
	322	{
	323	struct inode *inode = d_inode(dentry);
	324	struct nilfs_transaction_info ti;
	325	int err;
	326
	327	err = nilfs_transaction_begin(dir->i_sb, &ti, 0);
	328	if (err)
	329	return err;
	330
	331	err = -ENOTEMPTY;
	332	if (nilfs_empty_dir(inode)) {
	333	err = nilfs_do_unlink(dir, dentry);
	334	if (!err) {
	335	inode->i_size = 0;
	336	drop_nlink(inode);
	337	nilfs_mark_inode_dirty(inode);
	338	drop_nlink(dir);
	339	nilfs_mark_inode_dirty(dir);
	340	}
	341	}
	342	if (!err)
	343	err = nilfs_transaction_commit(dir->i_sb);
	344	else
	345	nilfs_transaction_abort(dir->i_sb);
	346
	347	return err;
	348	}
	349
	350	static int nilfs_rename(struct inode old_dir, struct dentry old_dentry,
	351	struct inode new_dir, struct dentry new_dentry,
	352	unsigned int flags)
	353	{
	354	struct inode *old_inode = d_inode(old_dentry);
	355	struct inode *new_inode = d_inode(new_dentry);
	356	struct page *dir_page = NULL;
	357	struct nilfs_dir_entry *dir_de = NULL;
	358	struct page *old_page;
	359	struct nilfs_dir_entry *old_de;
	360	struct nilfs_transaction_info ti;
	361	int err;
	362
	363	if (flags & ~RENAME_NOREPLACE)
	364	return -EINVAL;
	365
	366	err = nilfs_transaction_begin(old_dir->i_sb, &ti, 1);
	367	if (unlikely(err))
	368	return err;
	369
	370	err = -ENOENT;
	371	old_de = nilfs_find_entry(old_dir, &old_dentry->d_name, &old_page);
	372	if (!old_de)
	373	goto out;
	374
	375	if (S_ISDIR(old_inode->i_mode)) {
	376	err = -EIO;
	377	dir_de = nilfs_dotdot(old_inode, &dir_page);
	378	if (!dir_de)
	379	goto out_old;
	380	}
	381
	382	if (new_inode) {
	383	struct page *new_page;
	384	struct nilfs_dir_entry *new_de;
	385
	386	err = -ENOTEMPTY;
	387	if (dir_de && !nilfs_empty_dir(new_inode))
	388	goto out_dir;
	389
	390	err = -ENOENT;
	391	new_de = nilfs_find_entry(new_dir, &new_dentry->d_name, &new_page);
	392	if (!new_de)
	393	goto out_dir;
	394	nilfs_set_link(new_dir, new_de, new_page, old_inode);
	395	nilfs_mark_inode_dirty(new_dir);
	396	new_inode->i_ctime = current_time(new_inode);
	397	if (dir_de)
	398	drop_nlink(new_inode);
	399	drop_nlink(new_inode);
	400	nilfs_mark_inode_dirty(new_inode);
	401	} else {
	402	err = nilfs_add_link(new_dentry, old_inode);
	403	if (err)
	404	goto out_dir;
	405	if (dir_de) {
	406	inc_nlink(new_dir);
	407	nilfs_mark_inode_dirty(new_dir);
	408	}
	409	}
	410
	411	/*
	412	* Like most other Unix systems, set the ctime for inodes on a
	413	* rename.
	414	*/
	415	old_inode->i_ctime = current_time(old_inode);
	416
	417	nilfs_delete_entry(old_de, old_page);
	418
	419	if (dir_de) {
	420	nilfs_set_link(old_inode, dir_de, dir_page, new_dir);
	421	drop_nlink(old_dir);
	422	}
	423	nilfs_mark_inode_dirty(old_dir);
	424	nilfs_mark_inode_dirty(old_inode);
	425
	426	err = nilfs_transaction_commit(old_dir->i_sb);
	427	return err;
	428
	429	out_dir:
	430	if (dir_de) {
	431	kunmap(dir_page);
	432	put_page(dir_page);
	433	}
	434	out_old:
	435	kunmap(old_page);
	436	put_page(old_page);
	437	out:
	438	nilfs_transaction_abort(old_dir->i_sb);
	439	return err;
	440	}
	441
	442	/*
	443	* Export operations
	444	*/
	445	static struct dentry nilfs_get_parent(struct dentry child)
	446	{
	447	unsigned long ino;
	448	struct inode *inode;
	449	struct qstr dotdot = QSTR_INIT("..", 2);
	450	struct nilfs_root *root;
	451
	452	ino = nilfs_inode_by_name(d_inode(child), &dotdot);
	453	if (!ino)
	454	return ERR_PTR(-ENOENT);
	455
	456	root = NILFS_I(d_inode(child))->i_root;
	457
	458	inode = nilfs_iget(child->d_sb, root, ino);
	459	if (IS_ERR(inode))
	460	return ERR_CAST(inode);
	461
	462	return d_obtain_alias(inode);
	463	}
	464
	465	static struct dentry nilfs_get_dentry(struct super_block sb, u64 cno,
	466	u64 ino, u32 gen)
	467	{
	468	struct nilfs_root *root;
	469	struct inode *inode;
	470
	471	if (ino < NILFS_FIRST_INO(sb) && ino != NILFS_ROOT_INO)
	472	return ERR_PTR(-ESTALE);
	473
	474	root = nilfs_lookup_root(sb->s_fs_info, cno);
	475	if (!root)
	476	return ERR_PTR(-ESTALE);
	477
	478	inode = nilfs_iget(sb, root, ino);
	479	nilfs_put_root(root);
	480
	481	if (IS_ERR(inode))
	482	return ERR_CAST(inode);
	483	if (gen && inode->i_generation != gen) {
	484	iput(inode);
	485	return ERR_PTR(-ESTALE);
	486	}
	487	return d_obtain_alias(inode);
	488	}
	489
	490	static struct dentry nilfs_fh_to_dentry(struct super_block sb, struct fid *fh,
	491	int fh_len, int fh_type)
	492	{
	493	struct nilfs_fid fid = (struct nilfs_fid )fh;
	494
	495	if (fh_len < NILFS_FID_SIZE_NON_CONNECTABLE \|\|
	496	(fh_type != FILEID_NILFS_WITH_PARENT &&
	497	fh_type != FILEID_NILFS_WITHOUT_PARENT))
	498	return NULL;
	499
	500	return nilfs_get_dentry(sb, fid->cno, fid->ino, fid->gen);
	501	}
	502
	503	static struct dentry nilfs_fh_to_parent(struct super_block sb, struct fid *fh,
	504	int fh_len, int fh_type)
	505	{
	506	struct nilfs_fid fid = (struct nilfs_fid )fh;
	507
	508	if (fh_len < NILFS_FID_SIZE_CONNECTABLE \|\|
	509	fh_type != FILEID_NILFS_WITH_PARENT)
	510	return NULL;
	511
	512	return nilfs_get_dentry(sb, fid->cno, fid->parent_ino, fid->parent_gen);
	513	}
	514
	515	static int nilfs_encode_fh(struct inode inode, __u32 fh, int *lenp,
	516	struct inode *parent)
	517	{
	518	struct nilfs_fid fid = (struct nilfs_fid )fh;
	519	struct nilfs_root *root = NILFS_I(inode)->i_root;
	520	int type;
	521
	522	if (parent && *lenp < NILFS_FID_SIZE_CONNECTABLE) {
	523	*lenp = NILFS_FID_SIZE_CONNECTABLE;
	524	return FILEID_INVALID;
	525	}
	526	if (*lenp < NILFS_FID_SIZE_NON_CONNECTABLE) {
	527	*lenp = NILFS_FID_SIZE_NON_CONNECTABLE;
	528	return FILEID_INVALID;
	529	}
	530
	531	fid->cno = root->cno;
	532	fid->ino = inode->i_ino;
	533	fid->gen = inode->i_generation;
	534
	535	if (parent) {
	536	fid->parent_ino = parent->i_ino;
	537	fid->parent_gen = parent->i_generation;
	538	type = FILEID_NILFS_WITH_PARENT;
	539	*lenp = NILFS_FID_SIZE_CONNECTABLE;
	540	} else {
	541	type = FILEID_NILFS_WITHOUT_PARENT;
	542	*lenp = NILFS_FID_SIZE_NON_CONNECTABLE;
	543	}
	544
	545	return type;
	546	}
	547
	548	const struct inode_operations nilfs_dir_inode_operations = {
	549	.create = nilfs_create,
	550	.lookup = nilfs_lookup,
	551	.link = nilfs_link,
	552	.unlink = nilfs_unlink,
	553	.symlink = nilfs_symlink,
	554	.mkdir = nilfs_mkdir,
	555	.rmdir = nilfs_rmdir,
	556	.mknod = nilfs_mknod,
	557	.rename = nilfs_rename,
	558	.setattr = nilfs_setattr,
	559	.permission = nilfs_permission,
	560	.fiemap = nilfs_fiemap,
	561	};
	562
	563	const struct inode_operations nilfs_special_inode_operations = {
	564	.setattr = nilfs_setattr,
	565	.permission = nilfs_permission,
	566	};
	567
	568	const struct inode_operations nilfs_symlink_inode_operations = {
	569	.get_link = page_get_link,
	570	.permission = nilfs_permission,
	571	};
	572
	573	const struct export_operations nilfs_export_ops = {
	574	.encode_fh = nilfs_encode_fh,
	575	.fh_to_dentry = nilfs_fh_to_dentry,
	576	.fh_to_parent = nilfs_fh_to_parent,
	577	.get_parent = nilfs_get_parent,
	578	};