[linux-2.6-block.git] / fs / minix / namei.c

// SPDX-License-Identifier: GPL-2.0
/*
 *  linux/fs/minix/namei.c
 *
 *  Copyright (C) 1991, 1992  Linus Torvalds
 */

#include "minix.h"

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

static struct dentry *minix_lookup(struct inode * dir, struct dentry *dentry, unsigned int flags)
{
	struct inode * inode = NULL;
	ino_t ino;

	if (dentry->d_name.len > minix_sb(dir->i_sb)->s_namelen)
		return ERR_PTR(-ENAMETOOLONG);

	ino = minix_inode_by_name(dentry);
	if (ino)
		inode = minix_iget(dir->i_sb, ino);
	return d_splice_alias(inode, dentry);
}

static int minix_mknod(struct inode * dir, struct dentry *dentry, umode_t mode, dev_t rdev)
{
	int error;
	struct inode *inode;

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

	inode = minix_new_inode(dir, mode, &error);

	if (inode) {
		minix_set_inode(inode, rdev);
		mark_inode_dirty(inode);
		error = add_nondir(dentry, inode);
	}
	return error;
}

static int minix_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode)
{
	int error;
	struct inode *inode = minix_new_inode(dir, mode, &error);
	if (inode) {
		minix_set_inode(inode, 0);
		mark_inode_dirty(inode);
		d_tmpfile(dentry, inode);
	}
	return error;
}

static int minix_create(struct inode *dir, struct dentry *dentry, umode_t mode,
		bool excl)
{
	return minix_mknod(dir, dentry, mode, 0);
}

static int minix_symlink(struct inode * dir, struct dentry *dentry,
	  const char * symname)
{
	int err = -ENAMETOOLONG;
	int i = strlen(symname)+1;
	struct inode * inode;

	if (i > dir->i_sb->s_blocksize)
		goto out;

	inode = minix_new_inode(dir, S_IFLNK | 0777, &err);
	if (!inode)
		goto out;

	minix_set_inode(inode, 0);
	err = page_symlink(inode, symname, i);
	if (err)
		goto out_fail;

	err = add_nondir(dentry, inode);
out:
	return err;

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

static int minix_link(struct dentry * old_dentry, struct inode * dir,
	struct dentry *dentry)
{
	struct inode *inode = d_inode(old_dentry);

	inode->i_ctime = current_time(inode);
	inode_inc_link_count(inode);
	ihold(inode);
	return add_nondir(dentry, inode);
}

static int minix_mkdir(struct inode * dir, struct dentry *dentry, umode_t mode)
{
	struct inode * inode;
	int err;

	inode_inc_link_count(dir);

	inode = minix_new_inode(dir, S_IFDIR | mode, &err);
	if (!inode)
		goto out_dir;

	minix_set_inode(inode, 0);

	inode_inc_link_count(inode);

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

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

	d_instantiate(dentry, inode);
out:
	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 minix_unlink(struct inode * dir, struct dentry *dentry)
{
	int err = -ENOENT;
	struct inode * inode = d_inode(dentry);
	struct page * page;
	struct minix_dir_entry * de;

	de = minix_find_entry(dentry, &page);
	if (!de)
		goto end_unlink;

	err = minix_delete_entry(de, page);
	if (err)
		goto end_unlink;

	inode->i_ctime = dir->i_ctime;
	inode_dec_link_count(inode);
end_unlink:
	return err;
}

static int minix_rmdir(struct inode * dir, struct dentry *dentry)
{
	struct inode * inode = d_inode(dentry);
	int err = -ENOTEMPTY;

	if (minix_empty_dir(inode)) {
		err = minix_unlink(dir, dentry);
		if (!err) {
			inode_dec_link_count(dir);
			inode_dec_link_count(inode);
		}
	}
	return err;
}

static int minix_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 minix_dir_entry * dir_de = NULL;
	struct page * old_page;
	struct minix_dir_entry * old_de;
	int err = -ENOENT;

	if (flags & ~RENAME_NOREPLACE)
		return -EINVAL;

	old_de = minix_find_entry(old_dentry, &old_page);
	if (!old_de)
		goto out;

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

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

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

		err = -ENOENT;
		new_de = minix_find_entry(new_dentry, &new_page);
		if (!new_de)
			goto out_dir;
		minix_set_link(new_de, new_page, old_inode);
		new_inode->i_ctime = current_time(new_inode);
		if (dir_de)
			drop_nlink(new_inode);
		inode_dec_link_count(new_inode);
	} else {
		err = minix_add_link(new_dentry, old_inode);
		if (err)
			goto out_dir;
		if (dir_de)
			inode_inc_link_count(new_dir);
	}

	minix_delete_entry(old_de, old_page);
	mark_inode_dirty(old_inode);

	if (dir_de) {
		minix_set_link(dir_de, dir_page, new_dir);
		inode_dec_link_count(old_dir);
	}
	return 0;

out_dir:
	if (dir_de) {
		kunmap(dir_page);
		put_page(dir_page);
	}
out_old:
	kunmap(old_page);
	put_page(old_page);
out:
	return err;
}

/*
 * directories can handle most operations...
 */
const struct inode_operations minix_dir_inode_operations = {
	.create		= minix_create,
	.lookup		= minix_lookup,
	.link		= minix_link,
	.unlink		= minix_unlink,
	.symlink	= minix_symlink,
	.mkdir		= minix_mkdir,
	.rmdir		= minix_rmdir,
	.mknod		= minix_mknod,
	.rename		= minix_rename,
	.getattr	= minix_getattr,
	.tmpfile	= minix_tmpfile,
};
Commit	Line	Data
b2441318	1	// SPDX-License-Identifier: GPL-2.0
1da177e4 LT	2	/*
	3	* linux/fs/minix/namei.c
	4	*
	5	* Copyright (C) 1991, 1992 Linus Torvalds
	6	*/
	7
	8	#include "minix.h"
	9
1da177e4 LT	10	static int add_nondir(struct dentry dentry, struct inode inode)
	11	{
	12	int err = minix_add_link(dentry, inode);
	13	if (!err) {
	14	d_instantiate(dentry, inode);
	15	return 0;
	16	}
78ec7b69	17	inode_dec_link_count(inode);
1da177e4 LT	18	iput(inode);
	19	return err;
	20	}
	21
00cd8dd3	22	static struct dentry minix_lookup(struct inode dir, struct dentry *dentry, unsigned int flags)
1da177e4 LT	23	{
	24	struct inode * inode = NULL;
	25	ino_t ino;
	26
1da177e4 LT	27	if (dentry->d_name.len > minix_sb(dir->i_sb)->s_namelen)
	28	return ERR_PTR(-ENAMETOOLONG);
	29
	30	ino = minix_inode_by_name(dentry);
b0149516	31	if (ino)
a90a0880	32	inode = minix_iget(dir->i_sb, ino);
b0149516	33	return d_splice_alias(inode, dentry);
1da177e4 LT	34	}
1da177e4 LT	35
1a67aafb	36	static int minix_mknod(struct inode * dir, struct dentry *dentry, umode_t mode, dev_t rdev)
1da177e4 LT	37	{
	38	int error;
	39	struct inode *inode;
	40
	41	if (!old_valid_dev(rdev))
	42	return -EINVAL;
	43
9eed1fb7	44	inode = minix_new_inode(dir, mode, &error);
1da177e4 LT	45
1da177e4 LT	46	if (inode) {
1da177e4 LT	47	minix_set_inode(inode, rdev);
	48	mark_inode_dirty(inode);
	49	error = add_nondir(dentry, inode);
	50	}
	51	return error;
	52	}
	53
60545d0d AV	54	static int minix_tmpfile(struct inode dir, struct dentry dentry, umode_t mode)
	55	{
	56	int error;
	57	struct inode *inode = minix_new_inode(dir, mode, &error);
	58	if (inode) {
	59	minix_set_inode(inode, 0);
	60	mark_inode_dirty(inode);
	61	d_tmpfile(dentry, inode);
	62	}
	63	return error;
	64	}
	65
4acdaf27	66	static int minix_create(struct inode dir, struct dentry dentry, umode_t mode,
ebfc3b49	67	bool excl)
1da177e4 LT	68	{
	69	return minix_mknod(dir, dentry, mode, 0);
	70	}
	71
	72	static int minix_symlink(struct inode * dir, struct dentry *dentry,
	73	const char * symname)
	74	{
	75	int err = -ENAMETOOLONG;
	76	int i = strlen(symname)+1;
	77	struct inode * inode;
	78
	79	if (i > dir->i_sb->s_blocksize)
	80	goto out;
	81
9eed1fb7	82	inode = minix_new_inode(dir, S_IFLNK \| 0777, &err);
1da177e4 LT	83	if (!inode)
	84	goto out;
	85
1da177e4 LT	86	minix_set_inode(inode, 0);
	87	err = page_symlink(inode, symname, i);
	88	if (err)
	89	goto out_fail;
	90
	91	err = add_nondir(dentry, inode);
	92	out:
	93	return err;
	94
	95	out_fail:
78ec7b69	96	inode_dec_link_count(inode);
1da177e4 LT	97	iput(inode);
	98	goto out;
	99	}
	100
	101	static int minix_link(struct dentry * old_dentry, struct inode * dir,
	102	struct dentry *dentry)
	103	{
2b0143b5	104	struct inode *inode = d_inode(old_dentry);
1da177e4	105
02027d42	106	inode->i_ctime = current_time(inode);
78ec7b69	107	inode_inc_link_count(inode);
7de9c6ee	108	ihold(inode);
1da177e4 LT	109	return add_nondir(dentry, inode);
	110	}
	111
18bb1db3	112	static int minix_mkdir(struct inode * dir, struct dentry *dentry, umode_t mode)
1da177e4 LT	113	{
1da177e4 LT	114	struct inode * inode;
8de52778	115	int err;
1da177e4	116
78ec7b69	117	inode_inc_link_count(dir);
1da177e4	118
eee743fd	119	inode = minix_new_inode(dir, S_IFDIR \| mode, &err);
1da177e4 LT	120	if (!inode)
	121	goto out_dir;
	122
1da177e4 LT	123	minix_set_inode(inode, 0);
1da177e4 LT	124
78ec7b69	125	inode_inc_link_count(inode);
1da177e4 LT	126
	127	err = minix_make_empty(inode, dir);
	128	if (err)
	129	goto out_fail;
	130
	131	err = minix_add_link(dentry, inode);
	132	if (err)
	133	goto out_fail;
	134
	135	d_instantiate(dentry, inode);
	136	out:
	137	return err;
	138
	139	out_fail:
78ec7b69 AD	140	inode_dec_link_count(inode);
78ec7b69 AD	141	inode_dec_link_count(inode);
1da177e4 LT	142	iput(inode);
1da177e4 LT	143	out_dir:
78ec7b69	144	inode_dec_link_count(dir);
1da177e4 LT	145	goto out;
	146	}
	147
	148	static int minix_unlink(struct inode * dir, struct dentry *dentry)
	149	{
	150	int err = -ENOENT;
2b0143b5	151	struct inode * inode = d_inode(dentry);
1da177e4 LT	152	struct page * page;
	153	struct minix_dir_entry * de;
	154
	155	de = minix_find_entry(dentry, &page);
	156	if (!de)
	157	goto end_unlink;
	158
	159	err = minix_delete_entry(de, page);
	160	if (err)
	161	goto end_unlink;
	162
	163	inode->i_ctime = dir->i_ctime;
78ec7b69	164	inode_dec_link_count(inode);
1da177e4 LT	165	end_unlink:
	166	return err;
	167	}
	168
	169	static int minix_rmdir(struct inode * dir, struct dentry *dentry)
	170	{
2b0143b5	171	struct inode * inode = d_inode(dentry);
1da177e4 LT	172	int err = -ENOTEMPTY;
	173
	174	if (minix_empty_dir(inode)) {
	175	err = minix_unlink(dir, dentry);
	176	if (!err) {
78ec7b69 AD	177	inode_dec_link_count(dir);
78ec7b69 AD	178	inode_dec_link_count(inode);
1da177e4 LT	179	}
	180	}
	181	return err;
	182	}
	183
	184	static int minix_rename(struct inode * old_dir, struct dentry *old_dentry,
f03b8ad8 MS	185	struct inode * new_dir, struct dentry *new_dentry,
f03b8ad8 MS	186	unsigned int flags)
1da177e4	187	{
2b0143b5 DH	188	struct inode * old_inode = d_inode(old_dentry);
2b0143b5 DH	189	struct inode * new_inode = d_inode(new_dentry);
1da177e4 LT	190	struct page * dir_page = NULL;
	191	struct minix_dir_entry * dir_de = NULL;
	192	struct page * old_page;
	193	struct minix_dir_entry * old_de;
	194	int err = -ENOENT;
	195
f03b8ad8 MS	196	if (flags & ~RENAME_NOREPLACE)
	197	return -EINVAL;
	198
1da177e4 LT	199	old_de = minix_find_entry(old_dentry, &old_page);
	200	if (!old_de)
	201	goto out;
	202
	203	if (S_ISDIR(old_inode->i_mode)) {
	204	err = -EIO;
	205	dir_de = minix_dotdot(old_inode, &dir_page);
	206	if (!dir_de)
	207	goto out_old;
	208	}
	209
	210	if (new_inode) {
	211	struct page * new_page;
	212	struct minix_dir_entry * new_de;
	213
	214	err = -ENOTEMPTY;
	215	if (dir_de && !minix_empty_dir(new_inode))
	216	goto out_dir;
	217
	218	err = -ENOENT;
	219	new_de = minix_find_entry(new_dentry, &new_page);
	220	if (!new_de)
	221	goto out_dir;
1da177e4	222	minix_set_link(new_de, new_page, old_inode);
02027d42	223	new_inode->i_ctime = current_time(new_inode);
1da177e4	224	if (dir_de)
9a53c3a7	225	drop_nlink(new_inode);
78ec7b69	226	inode_dec_link_count(new_inode);
1da177e4	227	} else {
1da177e4	228	err = minix_add_link(new_dentry, old_inode);
6f88049c	229	if (err)
1da177e4	230	goto out_dir;
1da177e4	231	if (dir_de)
78ec7b69	232	inode_inc_link_count(new_dir);
1da177e4 LT	233	}
	234
	235	minix_delete_entry(old_de, old_page);
6f88049c	236	mark_inode_dirty(old_inode);
1da177e4 LT	237
	238	if (dir_de) {
	239	minix_set_link(dir_de, dir_page, new_dir);
78ec7b69	240	inode_dec_link_count(old_dir);
1da177e4 LT	241	}
	242	return 0;
	243
	244	out_dir:
	245	if (dir_de) {
	246	kunmap(dir_page);
09cbfeaf	247	put_page(dir_page);
1da177e4 LT	248	}
	249	out_old:
	250	kunmap(old_page);
09cbfeaf	251	put_page(old_page);
1da177e4 LT	252	out:
	253	return err;
	254	}
	255
	256	/*
	257	* directories can handle most operations...
	258	*/
92e1d5be	259	const struct inode_operations minix_dir_inode_operations = {
1da177e4 LT	260	.create = minix_create,
	261	.lookup = minix_lookup,
	262	.link = minix_link,
	263	.unlink = minix_unlink,
	264	.symlink = minix_symlink,
	265	.mkdir = minix_mkdir,
	266	.rmdir = minix_rmdir,
	267	.mknod = minix_mknod,
	268	.rename = minix_rename,
	269	.getattr = minix_getattr,
60545d0d	270	.tmpfile = minix_tmpfile,
1da177e4	271	};