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