[linux.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_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 = old_dentry->d_inode;

	inode->i_ctime = CURRENT_TIME_SEC;
	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 = dentry->d_inode;
	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 = dentry->d_inode;
	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)
{
	struct inode * old_inode = old_dentry->d_inode;
	struct inode * new_inode = new_dentry->d_inode;
	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;

	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_SEC;
		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);
		page_cache_release(dir_page);
	}
out_old:
	kunmap(old_page);
	page_cache_release(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,
};
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
4acdaf27	57	static int minix_create(struct inode dir, struct dentry dentry, umode_t mode,
ebfc3b49	58	bool excl)
1da177e4 LT	59	{
	60	return minix_mknod(dir, dentry, mode, 0);
	61	}
	62
	63	static int minix_symlink(struct inode * dir, struct dentry *dentry,
	64	const char * symname)
	65	{
	66	int err = -ENAMETOOLONG;
	67	int i = strlen(symname)+1;
	68	struct inode * inode;
	69
	70	if (i > dir->i_sb->s_blocksize)
	71	goto out;
	72
9eed1fb7	73	inode = minix_new_inode(dir, S_IFLNK \| 0777, &err);
1da177e4 LT	74	if (!inode)
	75	goto out;
	76
1da177e4 LT	77	minix_set_inode(inode, 0);
	78	err = page_symlink(inode, symname, i);
	79	if (err)
	80	goto out_fail;
	81
	82	err = add_nondir(dentry, inode);
	83	out:
	84	return err;
	85
	86	out_fail:
78ec7b69	87	inode_dec_link_count(inode);
1da177e4 LT	88	iput(inode);
	89	goto out;
	90	}
	91
	92	static int minix_link(struct dentry * old_dentry, struct inode * dir,
	93	struct dentry *dentry)
	94	{
	95	struct inode *inode = old_dentry->d_inode;
	96
1da177e4	97	inode->i_ctime = CURRENT_TIME_SEC;
78ec7b69	98	inode_inc_link_count(inode);
7de9c6ee	99	ihold(inode);
1da177e4 LT	100	return add_nondir(dentry, inode);
	101	}
	102
18bb1db3	103	static int minix_mkdir(struct inode * dir, struct dentry *dentry, umode_t mode)
1da177e4 LT	104	{
1da177e4 LT	105	struct inode * inode;
8de52778	106	int err;
1da177e4	107
78ec7b69	108	inode_inc_link_count(dir);
1da177e4	109
eee743fd	110	inode = minix_new_inode(dir, S_IFDIR \| mode, &err);
1da177e4 LT	111	if (!inode)
	112	goto out_dir;
	113
1da177e4 LT	114	minix_set_inode(inode, 0);
1da177e4 LT	115
78ec7b69	116	inode_inc_link_count(inode);
1da177e4 LT	117
	118	err = minix_make_empty(inode, dir);
	119	if (err)
	120	goto out_fail;
	121
	122	err = minix_add_link(dentry, inode);
	123	if (err)
	124	goto out_fail;
	125
	126	d_instantiate(dentry, inode);
	127	out:
	128	return err;
	129
	130	out_fail:
78ec7b69 AD	131	inode_dec_link_count(inode);
78ec7b69 AD	132	inode_dec_link_count(inode);
1da177e4 LT	133	iput(inode);
1da177e4 LT	134	out_dir:
78ec7b69	135	inode_dec_link_count(dir);
1da177e4 LT	136	goto out;
	137	}
	138
	139	static int minix_unlink(struct inode * dir, struct dentry *dentry)
	140	{
	141	int err = -ENOENT;
	142	struct inode * inode = dentry->d_inode;
	143	struct page * page;
	144	struct minix_dir_entry * de;
	145
	146	de = minix_find_entry(dentry, &page);
	147	if (!de)
	148	goto end_unlink;
	149
	150	err = minix_delete_entry(de, page);
	151	if (err)
	152	goto end_unlink;
	153
	154	inode->i_ctime = dir->i_ctime;
78ec7b69	155	inode_dec_link_count(inode);
1da177e4 LT	156	end_unlink:
	157	return err;
	158	}
	159
	160	static int minix_rmdir(struct inode * dir, struct dentry *dentry)
	161	{
	162	struct inode * inode = dentry->d_inode;
	163	int err = -ENOTEMPTY;
	164
	165	if (minix_empty_dir(inode)) {
	166	err = minix_unlink(dir, dentry);
	167	if (!err) {
78ec7b69 AD	168	inode_dec_link_count(dir);
78ec7b69 AD	169	inode_dec_link_count(inode);
1da177e4 LT	170	}
	171	}
	172	return err;
	173	}
	174
	175	static int minix_rename(struct inode * old_dir, struct dentry *old_dentry,
	176	struct inode * new_dir, struct dentry *new_dentry)
	177	{
1da177e4 LT	178	struct inode * old_inode = old_dentry->d_inode;
	179	struct inode * new_inode = new_dentry->d_inode;
	180	struct page * dir_page = NULL;
	181	struct minix_dir_entry * dir_de = NULL;
	182	struct page * old_page;
	183	struct minix_dir_entry * old_de;
	184	int err = -ENOENT;
	185
	186	old_de = minix_find_entry(old_dentry, &old_page);
	187	if (!old_de)
	188	goto out;
	189
	190	if (S_ISDIR(old_inode->i_mode)) {
	191	err = -EIO;
	192	dir_de = minix_dotdot(old_inode, &dir_page);
	193	if (!dir_de)
	194	goto out_old;
	195	}
	196
	197	if (new_inode) {
	198	struct page * new_page;
	199	struct minix_dir_entry * new_de;
	200
	201	err = -ENOTEMPTY;
	202	if (dir_de && !minix_empty_dir(new_inode))
	203	goto out_dir;
	204
	205	err = -ENOENT;
	206	new_de = minix_find_entry(new_dentry, &new_page);
	207	if (!new_de)
	208	goto out_dir;
1da177e4 LT	209	minix_set_link(new_de, new_page, old_inode);
	210	new_inode->i_ctime = CURRENT_TIME_SEC;
	211	if (dir_de)
9a53c3a7	212	drop_nlink(new_inode);
78ec7b69	213	inode_dec_link_count(new_inode);
1da177e4	214	} else {
1da177e4	215	err = minix_add_link(new_dentry, old_inode);
6f88049c	216	if (err)
1da177e4	217	goto out_dir;
1da177e4	218	if (dir_de)
78ec7b69	219	inode_inc_link_count(new_dir);
1da177e4 LT	220	}
	221
	222	minix_delete_entry(old_de, old_page);
6f88049c	223	mark_inode_dirty(old_inode);
1da177e4 LT	224
	225	if (dir_de) {
	226	minix_set_link(dir_de, dir_page, new_dir);
78ec7b69	227	inode_dec_link_count(old_dir);
1da177e4 LT	228	}
	229	return 0;
	230
	231	out_dir:
	232	if (dir_de) {
	233	kunmap(dir_page);
	234	page_cache_release(dir_page);
	235	}
	236	out_old:
	237	kunmap(old_page);
	238	page_cache_release(old_page);
	239	out:
	240	return err;
	241	}
	242
	243	/*
	244	* directories can handle most operations...
	245	*/
92e1d5be	246	const struct inode_operations minix_dir_inode_operations = {
1da177e4 LT	247	.create = minix_create,
	248	.lookup = minix_lookup,
	249	.link = minix_link,
	250	.unlink = minix_unlink,
	251	.symlink = minix_symlink,
	252	.mkdir = minix_mkdir,
	253	.rmdir = minix_rmdir,
	254	.mknod = minix_mknod,
	255	.rename = minix_rename,
	256	.getattr = minix_getattr,
	257	};