[linux.git] / fs / exofs / namei.c

/*
 * Copyright (C) 2005, 2006
 * Avishay Traeger ([email protected]) ([email protected])
 * Copyright (C) 2005, 2006
 * International Business Machines
 * Copyright (C) 2008, 2009
 * Boaz Harrosh <[email protected]>
 *
 * Copyrights for code taken from ext2:
 *     Copyright (C) 1992, 1993, 1994, 1995
 *     Remy Card ([email protected])
 *     Laboratoire MASI - Institut Blaise Pascal
 *     Universite Pierre et Marie Curie (Paris VI)
 *     from
 *     linux/fs/minix/inode.c
 *     Copyright (C) 1991, 1992  Linus Torvalds
 *
 * This file is part of exofs.
 *
 * exofs 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.  Since it is based on ext2, and the only
 * valid version of GPL for the Linux kernel is version 2, the only valid
 * version of GPL for exofs is version 2.
 *
 * exofs 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.
 *
 * You should have received a copy of the GNU General Public License
 * along with exofs; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */

#include "exofs.h"

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

static struct dentry *exofs_lookup(struct inode *dir, struct dentry *dentry,
				   struct nameidata *nd)
{
	struct inode *inode;
	ino_t ino;

	if (dentry->d_name.len > EXOFS_NAME_LEN)
		return ERR_PTR(-ENAMETOOLONG);

	ino = exofs_inode_by_name(dir, dentry);
	inode = NULL;
	if (ino) {
		inode = exofs_iget(dir->i_sb, ino);
		if (IS_ERR(inode))
			return ERR_CAST(inode);
	}
	return d_splice_alias(inode, dentry);
}

static int exofs_create(struct inode *dir, struct dentry *dentry, int mode,
			 struct nameidata *nd)
{
	struct inode *inode = exofs_new_inode(dir, mode);
	int err = PTR_ERR(inode);
	if (!IS_ERR(inode)) {
		inode->i_op = &exofs_file_inode_operations;
		inode->i_fop = &exofs_file_operations;
		inode->i_mapping->a_ops = &exofs_aops;
		mark_inode_dirty(inode);
		err = exofs_add_nondir(dentry, inode);
	}
	return err;
}

static int exofs_mknod(struct inode *dir, struct dentry *dentry, int mode,
		       dev_t rdev)
{
	struct inode *inode;
	int err;

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

	inode = exofs_new_inode(dir, mode);
	err = PTR_ERR(inode);
	if (!IS_ERR(inode)) {
		init_special_inode(inode, inode->i_mode, rdev);
		mark_inode_dirty(inode);
		err = exofs_add_nondir(dentry, inode);
	}
	return err;
}

static int exofs_symlink(struct inode *dir, struct dentry *dentry,
			  const char *symname)
{
	struct super_block *sb = dir->i_sb;
	int err = -ENAMETOOLONG;
	unsigned l = strlen(symname)+1;
	struct inode *inode;
	struct exofs_i_info *oi;

	if (l > sb->s_blocksize)
		goto out;

	inode = exofs_new_inode(dir, S_IFLNK | S_IRWXUGO);
	err = PTR_ERR(inode);
	if (IS_ERR(inode))
		goto out;

	oi = exofs_i(inode);
	if (l > sizeof(oi->i_data)) {
		/* slow symlink */
		inode->i_op = &exofs_symlink_inode_operations;
		inode->i_mapping->a_ops = &exofs_aops;
		memset(oi->i_data, 0, sizeof(oi->i_data));

		err = page_symlink(inode, symname, l);
		if (err)
			goto out_fail;
	} else {
		/* fast symlink */
		inode->i_op = &exofs_fast_symlink_inode_operations;
		memcpy(oi->i_data, symname, l);
		inode->i_size = l-1;
	}
	mark_inode_dirty(inode);

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

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

static int exofs_link(struct dentry *old_dentry, struct inode *dir,
		struct dentry *dentry)
{
	struct inode *inode = old_dentry->d_inode;

	if (inode->i_nlink >= EXOFS_LINK_MAX)
		return -EMLINK;

	inode->i_ctime = CURRENT_TIME;
	inode_inc_link_count(inode);
	atomic_inc(&inode->i_count);

	return exofs_add_nondir(dentry, inode);
}

static int exofs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
{
	struct inode *inode;
	int err = -EMLINK;

	if (dir->i_nlink >= EXOFS_LINK_MAX)
		goto out;

	inode_inc_link_count(dir);

	inode = exofs_new_inode(dir, S_IFDIR | mode);
	err = PTR_ERR(inode);
	if (IS_ERR(inode))
		goto out_dir;

	inode->i_op = &exofs_dir_inode_operations;
	inode->i_fop = &exofs_dir_operations;
	inode->i_mapping->a_ops = &exofs_aops;

	inode_inc_link_count(inode);

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

	err = exofs_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 exofs_unlink(struct inode *dir, struct dentry *dentry)
{
	struct inode *inode = dentry->d_inode;
	struct exofs_dir_entry *de;
	struct page *page;
	int err = -ENOENT;

	de = exofs_find_entry(dir, dentry, &page);
	if (!de)
		goto out;

	err = exofs_delete_entry(de, page);
	if (err)
		goto out;

	inode->i_ctime = dir->i_ctime;
	inode_dec_link_count(inode);
	err = 0;
out:
	return err;
}

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

	if (exofs_empty_dir(inode)) {
		err = exofs_unlink(dir, dentry);
		if (!err) {
			inode->i_size = 0;
			inode_dec_link_count(inode);
			inode_dec_link_count(dir);
		}
	}
	return err;
}

static int exofs_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 exofs_dir_entry *dir_de = NULL;
	struct page *old_page;
	struct exofs_dir_entry *old_de;
	int err = -ENOENT;

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

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

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

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

		err = -ENOENT;
		new_de = exofs_find_entry(new_dir, new_dentry, &new_page);
		if (!new_de)
			goto out_dir;
		inode_inc_link_count(old_inode);
		err = exofs_set_link(new_dir, new_de, new_page, old_inode);
		new_inode->i_ctime = CURRENT_TIME;
		if (dir_de)
			drop_nlink(new_inode);
		inode_dec_link_count(new_inode);
		if (err)
			goto out_dir;
	} else {
		if (dir_de) {
			err = -EMLINK;
			if (new_dir->i_nlink >= EXOFS_LINK_MAX)
				goto out_dir;
		}
		inode_inc_link_count(old_inode);
		err = exofs_add_link(new_dentry, old_inode);
		if (err) {
			inode_dec_link_count(old_inode);
			goto out_dir;
		}
		if (dir_de)
			inode_inc_link_count(new_dir);
	}

	old_inode->i_ctime = CURRENT_TIME;

	exofs_delete_entry(old_de, old_page);
	inode_dec_link_count(old_inode);

	if (dir_de) {
		err = exofs_set_link(old_inode, dir_de, dir_page, new_dir);
		inode_dec_link_count(old_dir);
		if (err)
			goto out_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;
}

const struct inode_operations exofs_dir_inode_operations = {
	.create 	= exofs_create,
	.lookup 	= exofs_lookup,
	.link   	= exofs_link,
	.unlink 	= exofs_unlink,
	.symlink	= exofs_symlink,
	.mkdir  	= exofs_mkdir,
	.rmdir  	= exofs_rmdir,
	.mknod  	= exofs_mknod,
	.rename 	= exofs_rename,
	.setattr	= exofs_setattr,
};

const struct inode_operations exofs_special_inode_operations = {
	.setattr	= exofs_setattr,
};
Commit	Line	Data
e6af00f1 BH	1	/*
	2	* Copyright (C) 2005, 2006
	3	* Avishay Traeger ([email protected]) ([email protected])
	4	* Copyright (C) 2005, 2006
	5	* International Business Machines
	6	* Copyright (C) 2008, 2009
	7	* Boaz Harrosh <[email protected]>
	8	*
	9	* Copyrights for code taken from ext2:
	10	* Copyright (C) 1992, 1993, 1994, 1995
	11	* Remy Card ([email protected])
	12	* Laboratoire MASI - Institut Blaise Pascal
	13	* Universite Pierre et Marie Curie (Paris VI)
	14	* from
	15	* linux/fs/minix/inode.c
	16	* Copyright (C) 1991, 1992 Linus Torvalds
	17	*
	18	* This file is part of exofs.
	19	*
	20	* exofs is free software; you can redistribute it and/or modify
	21	* it under the terms of the GNU General Public License as published by
	22	* the Free Software Foundation. Since it is based on ext2, and the only
	23	* valid version of GPL for the Linux kernel is version 2, the only valid
	24	* version of GPL for exofs is version 2.
	25	*
	26	* exofs is distributed in the hope that it will be useful,
	27	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	28	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	29	* GNU General Public License for more details.
	30	*
	31	* You should have received a copy of the GNU General Public License
	32	* along with exofs; if not, write to the Free Software
	33	* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
	34	*/
	35
	36	#include "exofs.h"
	37
	38	static inline int exofs_add_nondir(struct dentry dentry, struct inode inode)
	39	{
	40	int err = exofs_add_link(dentry, inode);
	41	if (!err) {
	42	d_instantiate(dentry, inode);
	43	return 0;
	44	}
	45	inode_dec_link_count(inode);
	46	iput(inode);
	47	return err;
	48	}
	49
	50	static struct dentry exofs_lookup(struct inode dir, struct dentry *dentry,
	51	struct nameidata *nd)
	52	{
	53	struct inode *inode;
	54	ino_t ino;
	55
	56	if (dentry->d_name.len > EXOFS_NAME_LEN)
	57	return ERR_PTR(-ENAMETOOLONG);
	58
	59	ino = exofs_inode_by_name(dir, dentry);
	60	inode = NULL;
	61	if (ino) {
	62	inode = exofs_iget(dir->i_sb, ino);
	63	if (IS_ERR(inode))
	64	return ERR_CAST(inode);
65	}
66	return d_splice_alias(inode, dentry);
67	}
68
69	static int exofs_create(struct inode dir, struct dentry dentry, int mode,
70	struct nameidata *nd)
71	{
72	struct inode *inode = exofs_new_inode(dir, mode);
73	int err = PTR_ERR(inode);
74	if (!IS_ERR(inode)) {
75	inode->i_op = &exofs_file_inode_operations;
76	inode->i_fop = &exofs_file_operations;
77	inode->i_mapping->a_ops = &exofs_aops;
78	mark_inode_dirty(inode);
79	err = exofs_add_nondir(dentry, inode);
80	}
81	return err;
82	}
83
84	static int exofs_mknod(struct inode dir, struct dentry dentry, int mode,
85	dev_t rdev)
86	{
87	struct inode *inode;
88	int err;
89
90	if (!new_valid_dev(rdev))
91	return -EINVAL;
92
93	inode = exofs_new_inode(dir, mode);
94	err = PTR_ERR(inode);
95	if (!IS_ERR(inode)) {
96	init_special_inode(inode, inode->i_mode, rdev);
97	mark_inode_dirty(inode);
98	err = exofs_add_nondir(dentry, inode);
99	}
100	return err;
101	}
102
103	static int exofs_symlink(struct inode dir, struct dentry dentry,
104	const char *symname)
105	{
106	struct super_block *sb = dir->i_sb;
107	int err = -ENAMETOOLONG;
108	unsigned l = strlen(symname)+1;
109	struct inode *inode;
110	struct exofs_i_info *oi;
111
112	if (l > sb->s_blocksize)
113	goto out;
114
115	inode = exofs_new_inode(dir, S_IFLNK \| S_IRWXUGO);
116	err = PTR_ERR(inode);
117	if (IS_ERR(inode))
118	goto out;
119
120	oi = exofs_i(inode);
121	if (l > sizeof(oi->i_data)) {
122	/* slow symlink */
123	inode->i_op = &exofs_symlink_inode_operations;
124	inode->i_mapping->a_ops = &exofs_aops;
125	memset(oi->i_data, 0, sizeof(oi->i_data));
126
127	err = page_symlink(inode, symname, l);
128	if (err)
129	goto out_fail;
130	} else {
131	/* fast symlink */
132	inode->i_op = &exofs_fast_symlink_inode_operations;
133	memcpy(oi->i_data, symname, l);
134	inode->i_size = l-1;
135	}
136	mark_inode_dirty(inode);
137
138	err = exofs_add_nondir(dentry, inode);
139	out:
140	return err;
141
142	out_fail:
143	inode_dec_link_count(inode);
144	iput(inode);
145	goto out;
146	}
147
148	static int exofs_link(struct dentry old_dentry, struct inode dir,
149	struct dentry *dentry)
150	{
151	struct inode *inode = old_dentry->d_inode;
152
153	if (inode->i_nlink >= EXOFS_LINK_MAX)
154	return -EMLINK;
155
156	inode->i_ctime = CURRENT_TIME;
157	inode_inc_link_count(inode);
158	atomic_inc(&inode->i_count);
159
160	return exofs_add_nondir(dentry, inode);
161	}
162
163	static int exofs_mkdir(struct inode dir, struct dentry dentry, int mode)
164	{
165	struct inode *inode;
166	int err = -EMLINK;
167
168	if (dir->i_nlink >= EXOFS_LINK_MAX)
169	goto out;
170
171	inode_inc_link_count(dir);
172
173	inode = exofs_new_inode(dir, S_IFDIR \| mode);
174	err = PTR_ERR(inode);
175	if (IS_ERR(inode))
176	goto out_dir;
177
178	inode->i_op = &exofs_dir_inode_operations;
179	inode->i_fop = &exofs_dir_operations;
180	inode->i_mapping->a_ops = &exofs_aops;
181
182	inode_inc_link_count(inode);
183
184	err = exofs_make_empty(inode, dir);
185	if (err)
186	goto out_fail;
187
188	err = exofs_add_link(dentry, inode);
189	if (err)
190	goto out_fail;
191
192	d_instantiate(dentry, inode);
193	out:
194	return err;
195
196	out_fail:
197	inode_dec_link_count(inode);
198	inode_dec_link_count(inode);
199	iput(inode);
200	out_dir:
201	inode_dec_link_count(dir);
202	goto out;
203	}
204
205	static int exofs_unlink(struct inode dir, struct dentry dentry)
206	{
207	struct inode *inode = dentry->d_inode;
208	struct exofs_dir_entry *de;
209	struct page *page;
210	int err = -ENOENT;
211
212	de = exofs_find_entry(dir, dentry, &page);
213	if (!de)
214	goto out;
215
216	err = exofs_delete_entry(de, page);
217	if (err)
218	goto out;
219
220	inode->i_ctime = dir->i_ctime;
221	inode_dec_link_count(inode);
222	err = 0;
223	out:
224	return err;
225	}
226
227	static int exofs_rmdir(struct inode dir, struct dentry dentry)
228	{
229	struct inode *inode = dentry->d_inode;
230	int err = -ENOTEMPTY;
231
232	if (exofs_empty_dir(inode)) {
233	err = exofs_unlink(dir, dentry);
234	if (!err) {
235	inode->i_size = 0;
236	inode_dec_link_count(inode);
237	inode_dec_link_count(dir);
238	}
239	}
240	return err;
241	}
242
243	static int exofs_rename(struct inode old_dir, struct dentry old_dentry,
244	struct inode new_dir, struct dentry new_dentry)
245	{
246	struct inode *old_inode = old_dentry->d_inode;
247	struct inode *new_inode = new_dentry->d_inode;
248	struct page *dir_page = NULL;
249	struct exofs_dir_entry *dir_de = NULL;
250	struct page *old_page;
251	struct exofs_dir_entry *old_de;
252	int err = -ENOENT;
253
254	old_de = exofs_find_entry(old_dir, old_dentry, &old_page);
255	if (!old_de)
256	goto out;
257
258	if (S_ISDIR(old_inode->i_mode)) {
259	err = -EIO;
260	dir_de = exofs_dotdot(old_inode, &dir_page);
261	if (!dir_de)
262	goto out_old;
263	}
264
265	if (new_inode) {
266	struct page *new_page;
267	struct exofs_dir_entry *new_de;
268
269	err = -ENOTEMPTY;
270	if (dir_de && !exofs_empty_dir(new_inode))
271	goto out_dir;
272
273	err = -ENOENT;
274	new_de = exofs_find_entry(new_dir, new_dentry, &new_page);
275	if (!new_de)
276	goto out_dir;
277	inode_inc_link_count(old_inode);
278	err = exofs_set_link(new_dir, new_de, new_page, old_inode);
279	new_inode->i_ctime = CURRENT_TIME;
280	if (dir_de)
281	drop_nlink(new_inode);
282	inode_dec_link_count(new_inode);
283	if (err)
284	goto out_dir;
285	} else {
286	if (dir_de) {
287	err = -EMLINK;
288	if (new_dir->i_nlink >= EXOFS_LINK_MAX)
289	goto out_dir;
290	}
291	inode_inc_link_count(old_inode);
292	err = exofs_add_link(new_dentry, old_inode);
293	if (err) {
294	inode_dec_link_count(old_inode);
295	goto out_dir;
296	}
297	if (dir_de)
298	inode_inc_link_count(new_dir);
299	}
300
301	old_inode->i_ctime = CURRENT_TIME;
302
303	exofs_delete_entry(old_de, old_page);
304	inode_dec_link_count(old_inode);
305
306	if (dir_de) {
307	err = exofs_set_link(old_inode, dir_de, dir_page, new_dir);
308	inode_dec_link_count(old_dir);
309	if (err)
310	goto out_dir;
311	}
312	return 0;
313
314
315	out_dir:
316	if (dir_de) {
317	kunmap(dir_page);
318	page_cache_release(dir_page);
319	}
320	out_old:
321	kunmap(old_page);
322	page_cache_release(old_page);
323	out:
324	return err;
325	}
326
327	const struct inode_operations exofs_dir_inode_operations = {
328	.create = exofs_create,
329	.lookup = exofs_lookup,
330	.link = exofs_link,
331	.unlink = exofs_unlink,
332	.symlink = exofs_symlink,
333	.mkdir = exofs_mkdir,
334	.rmdir = exofs_rmdir,
335	.mknod = exofs_mknod,
336	.rename = exofs_rename,
337	.setattr = exofs_setattr,
338	};
339
340	const struct inode_operations exofs_special_inode_operations = {
341	.setattr = exofs_setattr,
342	};