[mirror_ubuntu-bionic-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.
 *
 * 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(dentry, inode);
		unlock_new_inode(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 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_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(dentry, inode);
	unlock_new_inode(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_warning(inode->i_sb, __func__,
			      "deleting nonexistent file (%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)
{
	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;

	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);
		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 = {
	.readlink	= generic_readlink,
	.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
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	*
4b420ab4	16	* Modified for NILFS by Amagai Yoshiji and Ryusuke Konishi.
d2500652 RK	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"
8e656fd5	38	#include "export.h"
d2500652	39
8e656fd5 RK	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)
d2500652 RK	43
	44	static inline int nilfs_add_nondir(struct dentry dentry, struct inode inode)
	45	{
	46	int err = nilfs_add_link(dentry, inode);
4ad364ca	47
d2500652 RK	48	if (!err) {
d2500652 RK	49	d_instantiate(dentry, inode);
705304a8	50	unlock_new_inode(inode);
d2500652 RK	51	return 0;
	52	}
	53	inode_dec_link_count(inode);
705304a8	54	unlock_new_inode(inode);
d2500652 RK	55	iput(inode);
	56	return err;
	57	}
	58
	59	/*
	60	* Methods themselves.
	61	*/
	62
	63	static struct dentry *
00cd8dd3	64	nilfs_lookup(struct inode dir, struct dentry dentry, unsigned int flags)
d2500652 RK	65	{
	66	struct inode *inode;
	67	ino_t ino;
	68
	69	if (dentry->d_name.len > NILFS_NAME_LEN)
	70	return ERR_PTR(-ENAMETOOLONG);
	71
0319003d	72	ino = nilfs_inode_by_name(dir, &dentry->d_name);
a9049376	73	inode = ino ? nilfs_iget(dir->i_sb, NILFS_I(dir)->i_root, ino) : NULL;
d2500652 RK	74	return d_splice_alias(inode, dentry);
	75	}
	76
d2500652 RK	77	/*
	78	* By the time this is called, we already have created
	79	* the directory cache entry for the new file, but it
	80	* is so far negative - it has no inode.
	81	*
	82	* If the create succeeds, we fill in the inode information
	83	* with d_instantiate().
	84	*/
4acdaf27	85	static int nilfs_create(struct inode dir, struct dentry dentry, umode_t mode,
ebfc3b49	86	bool excl)
d2500652 RK	87	{
	88	struct inode *inode;
	89	struct nilfs_transaction_info ti;
47420c79	90	int err;
d2500652 RK	91
	92	err = nilfs_transaction_begin(dir->i_sb, &ti, 1);
	93	if (err)
	94	return err;
	95	inode = nilfs_new_inode(dir, mode);
	96	err = PTR_ERR(inode);
	97	if (!IS_ERR(inode)) {
	98	inode->i_op = &nilfs_file_inode_operations;
	99	inode->i_fop = &nilfs_file_operations;
	100	inode->i_mapping->a_ops = &nilfs_aops;
abdb318b	101	nilfs_mark_inode_dirty(inode);
d2500652 RK	102	err = nilfs_add_nondir(dentry, inode);
d2500652 RK	103	}
47420c79 RK	104	if (!err)
	105	err = nilfs_transaction_commit(dir->i_sb);
	106	else
	107	nilfs_transaction_abort(dir->i_sb);
	108
	109	return err;
d2500652 RK	110	}
	111
	112	static int
1a67aafb	113	nilfs_mknod(struct inode dir, struct dentry dentry, umode_t mode, dev_t rdev)
d2500652 RK	114	{
	115	struct inode *inode;
	116	struct nilfs_transaction_info ti;
47420c79	117	int err;
d2500652	118
d2500652 RK	119	err = nilfs_transaction_begin(dir->i_sb, &ti, 1);
	120	if (err)
	121	return err;
	122	inode = nilfs_new_inode(dir, mode);
	123	err = PTR_ERR(inode);
	124	if (!IS_ERR(inode)) {
	125	init_special_inode(inode, inode->i_mode, rdev);
abdb318b	126	nilfs_mark_inode_dirty(inode);
d2500652 RK	127	err = nilfs_add_nondir(dentry, inode);
d2500652 RK	128	}
47420c79 RK	129	if (!err)
	130	err = nilfs_transaction_commit(dir->i_sb);
	131	else
	132	nilfs_transaction_abort(dir->i_sb);
	133
	134	return err;
d2500652 RK	135	}
	136
	137	static int nilfs_symlink(struct inode dir, struct dentry dentry,
	138	const char *symname)
	139	{
	140	struct nilfs_transaction_info ti;
	141	struct super_block *sb = dir->i_sb;
	142	unsigned l = strlen(symname)+1;
	143	struct inode *inode;
47420c79	144	int err;
d2500652 RK	145
	146	if (l > sb->s_blocksize)
	147	return -ENAMETOOLONG;
	148
	149	err = nilfs_transaction_begin(dir->i_sb, &ti, 1);
	150	if (err)
	151	return err;
	152
	153	inode = nilfs_new_inode(dir, S_IFLNK \| S_IRWXUGO);
	154	err = PTR_ERR(inode);
	155	if (IS_ERR(inode))
	156	goto out;
	157
	158	/* slow symlink */
	159	inode->i_op = &nilfs_symlink_inode_operations;
21fc61c7	160	inode_nohighmem(inode);
d2500652 RK	161	inode->i_mapping->a_ops = &nilfs_aops;
	162	err = page_symlink(inode, symname, l);
	163	if (err)
	164	goto out_fail;
	165
	166	/* mark_inode_dirty(inode); */
9ca941d4	167	/* page_symlink() do this */
d2500652 RK	168
	169	err = nilfs_add_nondir(dentry, inode);
	170	out:
47420c79 RK	171	if (!err)
	172	err = nilfs_transaction_commit(dir->i_sb);
	173	else
	174	nilfs_transaction_abort(dir->i_sb);
	175
	176	return err;
d2500652 RK	177
d2500652 RK	178	out_fail:
565de406	179	drop_nlink(inode);
abdb318b	180	nilfs_mark_inode_dirty(inode);
705304a8	181	unlock_new_inode(inode);
d2500652 RK	182	iput(inode);
	183	goto out;
	184	}
	185
	186	static int nilfs_link(struct dentry old_dentry, struct inode dir,
	187	struct dentry *dentry)
	188	{
2b0143b5	189	struct inode *inode = d_inode(old_dentry);
d2500652	190	struct nilfs_transaction_info ti;
47420c79	191	int err;
d2500652	192
d2500652 RK	193	err = nilfs_transaction_begin(dir->i_sb, &ti, 1);
	194	if (err)
	195	return err;
	196
	197	inode->i_ctime = CURRENT_TIME;
	198	inode_inc_link_count(inode);
7de9c6ee	199	ihold(inode);
d2500652	200
705304a8 RK	201	err = nilfs_add_link(dentry, inode);
	202	if (!err) {
	203	d_instantiate(dentry, inode);
47420c79	204	err = nilfs_transaction_commit(dir->i_sb);
705304a8 RK	205	} else {
	206	inode_dec_link_count(inode);
	207	iput(inode);
47420c79	208	nilfs_transaction_abort(dir->i_sb);
705304a8	209	}
47420c79 RK	210
47420c79 RK	211	return err;
d2500652 RK	212	}
d2500652 RK	213
18bb1db3	214	static int nilfs_mkdir(struct inode dir, struct dentry dentry, umode_t mode)
d2500652 RK	215	{
	216	struct inode *inode;
	217	struct nilfs_transaction_info ti;
47420c79	218	int err;
d2500652	219
d2500652 RK	220	err = nilfs_transaction_begin(dir->i_sb, &ti, 1);
	221	if (err)
	222	return err;
	223
565de406	224	inc_nlink(dir);
d2500652 RK	225
	226	inode = nilfs_new_inode(dir, S_IFDIR \| mode);
	227	err = PTR_ERR(inode);
	228	if (IS_ERR(inode))
	229	goto out_dir;
	230
	231	inode->i_op = &nilfs_dir_inode_operations;
	232	inode->i_fop = &nilfs_dir_operations;
	233	inode->i_mapping->a_ops = &nilfs_aops;
	234
565de406	235	inc_nlink(inode);
d2500652 RK	236
	237	err = nilfs_make_empty(inode, dir);
	238	if (err)
	239	goto out_fail;
	240
	241	err = nilfs_add_link(dentry, inode);
	242	if (err)
	243	goto out_fail;
	244
abdb318b	245	nilfs_mark_inode_dirty(inode);
d2500652	246	d_instantiate(dentry, inode);
705304a8	247	unlock_new_inode(inode);
d2500652	248	out:
47420c79 RK	249	if (!err)
	250	err = nilfs_transaction_commit(dir->i_sb);
	251	else
	252	nilfs_transaction_abort(dir->i_sb);
	253
	254	return err;
d2500652 RK	255
d2500652 RK	256	out_fail:
565de406	257	drop_nlink(inode);
565de406	258	drop_nlink(inode);
abdb318b	259	nilfs_mark_inode_dirty(inode);
705304a8	260	unlock_new_inode(inode);
d2500652 RK	261	iput(inode);
d2500652 RK	262	out_dir:
565de406	263	drop_nlink(dir);
abdb318b	264	nilfs_mark_inode_dirty(dir);
d2500652 RK	265	goto out;
	266	}
	267
4cd76c3c	268	static int nilfs_do_unlink(struct inode dir, struct dentry dentry)
d2500652 RK	269	{
	270	struct inode *inode;
	271	struct nilfs_dir_entry *de;
	272	struct page *page;
47420c79	273	int err;
d2500652	274
d2500652	275	err = -ENOENT;
0319003d	276	de = nilfs_find_entry(dir, &dentry->d_name, &page);
d2500652 RK	277	if (!de)
	278	goto out;
	279
2b0143b5	280	inode = d_inode(dentry);
d2500652 RK	281	err = -EIO;
	282	if (le64_to_cpu(de->inode) != inode->i_ino)
	283	goto out;
	284
	285	if (!inode->i_nlink) {
	286	nilfs_warning(inode->i_sb, __func__,
06f4abf6	287	"deleting nonexistent file (%lu), %d",
d2500652	288	inode->i_ino, inode->i_nlink);
bfe86848	289	set_nlink(inode, 1);
d2500652 RK	290	}
	291	err = nilfs_delete_entry(de, page);
	292	if (err)
	293	goto out;
	294
	295	inode->i_ctime = dir->i_ctime;
565de406	296	drop_nlink(inode);
d2500652 RK	297	err = 0;
d2500652 RK	298	out:
4cd76c3c JS	299	return err;
	300	}
	301
	302	static int nilfs_unlink(struct inode dir, struct dentry dentry)
	303	{
	304	struct nilfs_transaction_info ti;
	305	int err;
	306
	307	err = nilfs_transaction_begin(dir->i_sb, &ti, 0);
	308	if (err)
	309	return err;
	310
	311	err = nilfs_do_unlink(dir, dentry);
	312
	313	if (!err) {
abdb318b	314	nilfs_mark_inode_dirty(dir);
2b0143b5	315	nilfs_mark_inode_dirty(d_inode(dentry));
47420c79	316	err = nilfs_transaction_commit(dir->i_sb);
4cd76c3c	317	} else
47420c79 RK	318	nilfs_transaction_abort(dir->i_sb);
	319
	320	return err;
d2500652 RK	321	}
	322
	323	static int nilfs_rmdir(struct inode dir, struct dentry dentry)
	324	{
2b0143b5	325	struct inode *inode = d_inode(dentry);
d2500652	326	struct nilfs_transaction_info ti;
47420c79	327	int err;
d2500652 RK	328
	329	err = nilfs_transaction_begin(dir->i_sb, &ti, 0);
	330	if (err)
	331	return err;
	332
	333	err = -ENOTEMPTY;
	334	if (nilfs_empty_dir(inode)) {
4cd76c3c	335	err = nilfs_do_unlink(dir, dentry);
d2500652 RK	336	if (!err) {
d2500652 RK	337	inode->i_size = 0;
565de406	338	drop_nlink(inode);
abdb318b	339	nilfs_mark_inode_dirty(inode);
565de406	340	drop_nlink(dir);
abdb318b	341	nilfs_mark_inode_dirty(dir);
d2500652 RK	342	}
d2500652 RK	343	}
47420c79 RK	344	if (!err)
	345	err = nilfs_transaction_commit(dir->i_sb);
	346	else
	347	nilfs_transaction_abort(dir->i_sb);
	348
	349	return err;
d2500652 RK	350	}
	351
	352	static int nilfs_rename(struct inode old_dir, struct dentry old_dentry,
	353	struct inode new_dir, struct dentry new_dentry)
	354	{
2b0143b5 DH	355	struct inode *old_inode = d_inode(old_dentry);
2b0143b5 DH	356	struct inode *new_inode = d_inode(new_dentry);
d2500652 RK	357	struct page *dir_page = NULL;
	358	struct nilfs_dir_entry *dir_de = NULL;
	359	struct page *old_page;
	360	struct nilfs_dir_entry *old_de;
	361	struct nilfs_transaction_info ti;
	362	int err;
	363
	364	err = nilfs_transaction_begin(old_dir->i_sb, &ti, 1);
	365	if (unlikely(err))
	366	return err;
	367
	368	err = -ENOENT;
0319003d	369	old_de = nilfs_find_entry(old_dir, &old_dentry->d_name, &old_page);
d2500652 RK	370	if (!old_de)
	371	goto out;
	372
	373	if (S_ISDIR(old_inode->i_mode)) {
	374	err = -EIO;
	375	dir_de = nilfs_dotdot(old_inode, &dir_page);
	376	if (!dir_de)
	377	goto out_old;
	378	}
	379
	380	if (new_inode) {
	381	struct page *new_page;
	382	struct nilfs_dir_entry *new_de;
	383
	384	err = -ENOTEMPTY;
	385	if (dir_de && !nilfs_empty_dir(new_inode))
	386	goto out_dir;
	387
	388	err = -ENOENT;
0319003d	389	new_de = nilfs_find_entry(new_dir, &new_dentry->d_name, &new_page);
d2500652 RK	390	if (!new_de)
d2500652 RK	391	goto out_dir;
d2500652	392	nilfs_set_link(new_dir, new_de, new_page, old_inode);
abdb318b	393	nilfs_mark_inode_dirty(new_dir);
d2500652 RK	394	new_inode->i_ctime = CURRENT_TIME;
	395	if (dir_de)
	396	drop_nlink(new_inode);
565de406	397	drop_nlink(new_inode);
abdb318b	398	nilfs_mark_inode_dirty(new_inode);
d2500652	399	} else {
d2500652	400	err = nilfs_add_link(new_dentry, old_inode);
30eb43d3	401	if (err)
d2500652	402	goto out_dir;
565de406 JS	403	if (dir_de) {
565de406 JS	404	inc_nlink(new_dir);
abdb318b	405	nilfs_mark_inode_dirty(new_dir);
565de406	406	}
d2500652 RK	407	}
	408
	409	/*
	410	* Like most other Unix systems, set the ctime for inodes on a
	411	* rename.
d2500652 RK	412	*/
	413	old_inode->i_ctime = CURRENT_TIME;
	414
	415	nilfs_delete_entry(old_de, old_page);
d2500652 RK	416
	417	if (dir_de) {
	418	nilfs_set_link(old_inode, dir_de, dir_page, new_dir);
565de406	419	drop_nlink(old_dir);
d2500652	420	}
abdb318b JS	421	nilfs_mark_inode_dirty(old_dir);
abdb318b JS	422	nilfs_mark_inode_dirty(old_inode);
d2500652	423
47420c79	424	err = nilfs_transaction_commit(old_dir->i_sb);
d2500652 RK	425	return err;
	426
	427	out_dir:
	428	if (dir_de) {
	429	kunmap(dir_page);
09cbfeaf	430	put_page(dir_page);
d2500652 RK	431	}
	432	out_old:
	433	kunmap(old_page);
09cbfeaf	434	put_page(old_page);
d2500652	435	out:
47420c79	436	nilfs_transaction_abort(old_dir->i_sb);
d2500652 RK	437	return err;
	438	}
	439
8e656fd5 RK	440	/*
	441	* Export operations
	442	*/
	443	static struct dentry nilfs_get_parent(struct dentry child)
	444	{
	445	unsigned long ino;
	446	struct inode *inode;
26fe5750	447	struct qstr dotdot = QSTR_INIT("..", 2);
8e656fd5 RK	448	struct nilfs_root *root;
8e656fd5 RK	449
2b0143b5	450	ino = nilfs_inode_by_name(d_inode(child), &dotdot);
8e656fd5 RK	451	if (!ino)
	452	return ERR_PTR(-ENOENT);
	453
2b0143b5	454	root = NILFS_I(d_inode(child))->i_root;
8e656fd5	455
fc64005c	456	inode = nilfs_iget(child->d_sb, root, ino);
8e656fd5 RK	457	if (IS_ERR(inode))
	458	return ERR_CAST(inode);
	459
	460	return d_obtain_alias(inode);
	461	}
	462
	463	static struct dentry nilfs_get_dentry(struct super_block sb, u64 cno,
	464	u64 ino, u32 gen)
	465	{
	466	struct nilfs_root *root;
	467	struct inode *inode;
	468
	469	if (ino < NILFS_FIRST_INO(sb) && ino != NILFS_ROOT_INO)
	470	return ERR_PTR(-ESTALE);
	471
e3154e97	472	root = nilfs_lookup_root(sb->s_fs_info, cno);
8e656fd5 RK	473	if (!root)
	474	return ERR_PTR(-ESTALE);
	475
	476	inode = nilfs_iget(sb, root, ino);
	477	nilfs_put_root(root);
	478
	479	if (IS_ERR(inode))
	480	return ERR_CAST(inode);
	481	if (gen && inode->i_generation != gen) {
	482	iput(inode);
	483	return ERR_PTR(-ESTALE);
	484	}
	485	return d_obtain_alias(inode);
	486	}
	487
	488	static struct dentry nilfs_fh_to_dentry(struct super_block sb, struct fid *fh,
	489	int fh_len, int fh_type)
	490	{
	491	struct nilfs_fid fid = (struct nilfs_fid )fh;
	492
f73c2f1f	493	if (fh_len < NILFS_FID_SIZE_NON_CONNECTABLE \|\|
8e656fd5 RK	494	(fh_type != FILEID_NILFS_WITH_PARENT &&
	495	fh_type != FILEID_NILFS_WITHOUT_PARENT))
	496	return NULL;
	497
	498	return nilfs_get_dentry(sb, fid->cno, fid->ino, fid->gen);
	499	}
	500
	501	static struct dentry nilfs_fh_to_parent(struct super_block sb, struct fid *fh,
	502	int fh_len, int fh_type)
	503	{
	504	struct nilfs_fid fid = (struct nilfs_fid )fh;
	505
f73c2f1f	506	if (fh_len < NILFS_FID_SIZE_CONNECTABLE \|\|
8e656fd5 RK	507	fh_type != FILEID_NILFS_WITH_PARENT)
	508	return NULL;
	509
	510	return nilfs_get_dentry(sb, fid->cno, fid->parent_ino, fid->parent_gen);
	511	}
	512
b0b0382b AV	513	static int nilfs_encode_fh(struct inode inode, __u32 fh, int *lenp,
b0b0382b AV	514	struct inode *parent)
8e656fd5 RK	515	{
8e656fd5 RK	516	struct nilfs_fid fid = (struct nilfs_fid )fh;
8e656fd5 RK	517	struct nilfs_root *root = NILFS_I(inode)->i_root;
	518	int type;
	519
b0b0382b AV	520	if (parent && *lenp < NILFS_FID_SIZE_CONNECTABLE) {
b0b0382b AV	521	*lenp = NILFS_FID_SIZE_CONNECTABLE;
94e07a75	522	return FILEID_INVALID;
b0b0382b AV	523	}
	524	if (*lenp < NILFS_FID_SIZE_NON_CONNECTABLE) {
	525	*lenp = NILFS_FID_SIZE_NON_CONNECTABLE;
94e07a75	526	return FILEID_INVALID;
b0b0382b	527	}
8e656fd5 RK	528
	529	fid->cno = root->cno;
	530	fid->ino = inode->i_ino;
	531	fid->gen = inode->i_generation;
	532
b0b0382b	533	if (parent) {
8e656fd5 RK	534	fid->parent_ino = parent->i_ino;
8e656fd5 RK	535	fid->parent_gen = parent->i_generation;
8e656fd5 RK	536	type = FILEID_NILFS_WITH_PARENT;
	537	*lenp = NILFS_FID_SIZE_CONNECTABLE;
	538	} else {
	539	type = FILEID_NILFS_WITHOUT_PARENT;
	540	*lenp = NILFS_FID_SIZE_NON_CONNECTABLE;
	541	}
	542
	543	return type;
	544	}
	545
6e1d5dcc	546	const struct inode_operations nilfs_dir_inode_operations = {
d2500652 RK	547	.create = nilfs_create,
	548	.lookup = nilfs_lookup,
	549	.link = nilfs_link,
	550	.unlink = nilfs_unlink,
	551	.symlink = nilfs_symlink,
	552	.mkdir = nilfs_mkdir,
	553	.rmdir = nilfs_rmdir,
	554	.mknod = nilfs_mknod,
	555	.rename = nilfs_rename,
	556	.setattr = nilfs_setattr,
	557	.permission = nilfs_permission,
622daaff	558	.fiemap = nilfs_fiemap,
d2500652 RK	559	};
d2500652 RK	560
6e1d5dcc	561	const struct inode_operations nilfs_special_inode_operations = {
d2500652 RK	562	.setattr = nilfs_setattr,
	563	.permission = nilfs_permission,
	564	};
	565
6e1d5dcc	566	const struct inode_operations nilfs_symlink_inode_operations = {
d2500652	567	.readlink = generic_readlink,
6b255391	568	.get_link = page_get_link,
dc3d3b81	569	.permission = nilfs_permission,
d2500652	570	};
8e656fd5 RK	571
	572	const struct export_operations nilfs_export_ops = {
	573	.encode_fh = nilfs_encode_fh,
	574	.fh_to_dentry = nilfs_fh_to_dentry,
	575	.fh_to_parent = nilfs_fh_to_parent,
	576	.get_parent = nilfs_get_parent,
	577	};