[mirror_ubuntu-zesty-kernel.git] / fs / minix / namei.c

/*
 *  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);
		if (IS_ERR(inode))
			return ERR_CAST(inode);
	}
	d_add(dentry, inode);
	return NULL;
}

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
1da177e4 LT	1	/*
	2	* linux/fs/minix/namei.c
	3	*
	4	* Copyright (C) 1991, 1992 Linus Torvalds
	5	*/
	6
	7	#include "minix.h"
	8
1da177e4 LT	9	static int add_nondir(struct dentry dentry, struct inode inode)
	10	{
	11	int err = minix_add_link(dentry, inode);
	12	if (!err) {
	13	d_instantiate(dentry, inode);
	14	return 0;
	15	}
78ec7b69	16	inode_dec_link_count(inode);
1da177e4 LT	17	iput(inode);
	18	return err;
	19	}
	20
00cd8dd3	21	static struct dentry minix_lookup(struct inode dir, struct dentry *dentry, unsigned int flags)
1da177e4 LT	22	{
	23	struct inode * inode = NULL;
	24	ino_t ino;
	25
1da177e4 LT	26	if (dentry->d_name.len > minix_sb(dir->i_sb)->s_namelen)
	27	return ERR_PTR(-ENAMETOOLONG);
	28
	29	ino = minix_inode_by_name(dentry);
	30	if (ino) {
a90a0880 DH	31	inode = minix_iget(dir->i_sb, ino);
	32	if (IS_ERR(inode))
	33	return ERR_CAST(inode);
1da177e4 LT	34	}
	35	d_add(dentry, inode);
	36	return NULL;
	37	}
	38
1a67aafb	39	static int minix_mknod(struct inode * dir, struct dentry *dentry, umode_t mode, dev_t rdev)
1da177e4 LT	40	{
	41	int error;
	42	struct inode *inode;
	43
	44	if (!old_valid_dev(rdev))
	45	return -EINVAL;
	46
9eed1fb7	47	inode = minix_new_inode(dir, mode, &error);
1da177e4 LT	48
1da177e4 LT	49	if (inode) {
1da177e4 LT	50	minix_set_inode(inode, rdev);
	51	mark_inode_dirty(inode);
	52	error = add_nondir(dentry, inode);
	53	}
	54	return error;
	55	}
	56
60545d0d AV	57	static int minix_tmpfile(struct inode dir, struct dentry dentry, umode_t mode)
	58	{
	59	int error;
	60	struct inode *inode = minix_new_inode(dir, mode, &error);
	61	if (inode) {
	62	minix_set_inode(inode, 0);
	63	mark_inode_dirty(inode);
	64	d_tmpfile(dentry, inode);
	65	}
	66	return error;
	67	}
	68
4acdaf27	69	static int minix_create(struct inode dir, struct dentry dentry, umode_t mode,
ebfc3b49	70	bool excl)
1da177e4 LT	71	{
	72	return minix_mknod(dir, dentry, mode, 0);
	73	}
	74
	75	static int minix_symlink(struct inode * dir, struct dentry *dentry,
	76	const char * symname)
	77	{
	78	int err = -ENAMETOOLONG;
	79	int i = strlen(symname)+1;
	80	struct inode * inode;
	81
	82	if (i > dir->i_sb->s_blocksize)
	83	goto out;
	84
9eed1fb7	85	inode = minix_new_inode(dir, S_IFLNK \| 0777, &err);
1da177e4 LT	86	if (!inode)
	87	goto out;
	88
1da177e4 LT	89	minix_set_inode(inode, 0);
	90	err = page_symlink(inode, symname, i);
	91	if (err)
	92	goto out_fail;
	93
	94	err = add_nondir(dentry, inode);
	95	out:
	96	return err;
	97
	98	out_fail:
78ec7b69	99	inode_dec_link_count(inode);
1da177e4 LT	100	iput(inode);
	101	goto out;
	102	}
	103
	104	static int minix_link(struct dentry * old_dentry, struct inode * dir,
	105	struct dentry *dentry)
	106	{
2b0143b5	107	struct inode *inode = d_inode(old_dentry);
1da177e4	108
02027d42	109	inode->i_ctime = current_time(inode);
78ec7b69	110	inode_inc_link_count(inode);
7de9c6ee	111	ihold(inode);
1da177e4 LT	112	return add_nondir(dentry, inode);
	113	}
	114
18bb1db3	115	static int minix_mkdir(struct inode * dir, struct dentry *dentry, umode_t mode)
1da177e4 LT	116	{
1da177e4 LT	117	struct inode * inode;
8de52778	118	int err;
1da177e4	119
78ec7b69	120	inode_inc_link_count(dir);
1da177e4	121
eee743fd	122	inode = minix_new_inode(dir, S_IFDIR \| mode, &err);
1da177e4 LT	123	if (!inode)
	124	goto out_dir;
	125
1da177e4 LT	126	minix_set_inode(inode, 0);
1da177e4 LT	127
78ec7b69	128	inode_inc_link_count(inode);
1da177e4 LT	129
	130	err = minix_make_empty(inode, dir);
	131	if (err)
	132	goto out_fail;
	133
	134	err = minix_add_link(dentry, inode);
	135	if (err)
	136	goto out_fail;
	137
	138	d_instantiate(dentry, inode);
	139	out:
	140	return err;
	141
	142	out_fail:
78ec7b69 AD	143	inode_dec_link_count(inode);
78ec7b69 AD	144	inode_dec_link_count(inode);
1da177e4 LT	145	iput(inode);
1da177e4 LT	146	out_dir:
78ec7b69	147	inode_dec_link_count(dir);
1da177e4 LT	148	goto out;
	149	}
	150
	151	static int minix_unlink(struct inode * dir, struct dentry *dentry)
	152	{
	153	int err = -ENOENT;
2b0143b5	154	struct inode * inode = d_inode(dentry);
1da177e4 LT	155	struct page * page;
	156	struct minix_dir_entry * de;
	157
	158	de = minix_find_entry(dentry, &page);
	159	if (!de)
	160	goto end_unlink;
	161
	162	err = minix_delete_entry(de, page);
	163	if (err)
	164	goto end_unlink;
	165
	166	inode->i_ctime = dir->i_ctime;
78ec7b69	167	inode_dec_link_count(inode);
1da177e4 LT	168	end_unlink:
	169	return err;
	170	}
	171
	172	static int minix_rmdir(struct inode * dir, struct dentry *dentry)
	173	{
2b0143b5	174	struct inode * inode = d_inode(dentry);
1da177e4 LT	175	int err = -ENOTEMPTY;
	176
	177	if (minix_empty_dir(inode)) {
	178	err = minix_unlink(dir, dentry);
	179	if (!err) {
78ec7b69 AD	180	inode_dec_link_count(dir);
78ec7b69 AD	181	inode_dec_link_count(inode);
1da177e4 LT	182	}
	183	}
	184	return err;
	185	}
	186
	187	static int minix_rename(struct inode * old_dir, struct dentry *old_dentry,
f03b8ad8 MS	188	struct inode * new_dir, struct dentry *new_dentry,
f03b8ad8 MS	189	unsigned int flags)
1da177e4	190	{
2b0143b5 DH	191	struct inode * old_inode = d_inode(old_dentry);
2b0143b5 DH	192	struct inode * new_inode = d_inode(new_dentry);
1da177e4 LT	193	struct page * dir_page = NULL;
	194	struct minix_dir_entry * dir_de = NULL;
	195	struct page * old_page;
	196	struct minix_dir_entry * old_de;
	197	int err = -ENOENT;
	198
f03b8ad8 MS	199	if (flags & ~RENAME_NOREPLACE)
	200	return -EINVAL;
	201
1da177e4 LT	202	old_de = minix_find_entry(old_dentry, &old_page);
	203	if (!old_de)
	204	goto out;
	205
	206	if (S_ISDIR(old_inode->i_mode)) {
	207	err = -EIO;
	208	dir_de = minix_dotdot(old_inode, &dir_page);
	209	if (!dir_de)
	210	goto out_old;
	211	}
	212
	213	if (new_inode) {
	214	struct page * new_page;
	215	struct minix_dir_entry * new_de;
	216
	217	err = -ENOTEMPTY;
	218	if (dir_de && !minix_empty_dir(new_inode))
	219	goto out_dir;
	220
	221	err = -ENOENT;
	222	new_de = minix_find_entry(new_dentry, &new_page);
	223	if (!new_de)
	224	goto out_dir;
1da177e4	225	minix_set_link(new_de, new_page, old_inode);
02027d42	226	new_inode->i_ctime = current_time(new_inode);
1da177e4	227	if (dir_de)
9a53c3a7	228	drop_nlink(new_inode);
78ec7b69	229	inode_dec_link_count(new_inode);
1da177e4	230	} else {
1da177e4	231	err = minix_add_link(new_dentry, old_inode);
6f88049c	232	if (err)
1da177e4	233	goto out_dir;
1da177e4	234	if (dir_de)
78ec7b69	235	inode_inc_link_count(new_dir);
1da177e4 LT	236	}
	237
	238	minix_delete_entry(old_de, old_page);
6f88049c	239	mark_inode_dirty(old_inode);
1da177e4 LT	240
	241	if (dir_de) {
	242	minix_set_link(dir_de, dir_page, new_dir);
78ec7b69	243	inode_dec_link_count(old_dir);
1da177e4 LT	244	}
	245	return 0;
	246
	247	out_dir:
	248	if (dir_de) {
	249	kunmap(dir_page);
09cbfeaf	250	put_page(dir_page);
1da177e4 LT	251	}
	252	out_old:
	253	kunmap(old_page);
09cbfeaf	254	put_page(old_page);
1da177e4 LT	255	out:
	256	return err;
	257	}
	258
	259	/*
	260	* directories can handle most operations...
	261	*/
92e1d5be	262	const struct inode_operations minix_dir_inode_operations = {
1da177e4 LT	263	.create = minix_create,
	264	.lookup = minix_lookup,
	265	.link = minix_link,
	266	.unlink = minix_unlink,
	267	.symlink = minix_symlink,
	268	.mkdir = minix_mkdir,
	269	.rmdir = minix_rmdir,
	270	.mknod = minix_mknod,
	271	.rename = minix_rename,
	272	.getattr = minix_getattr,
60545d0d	273	.tmpfile = minix_tmpfile,
1da177e4	274	};