tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * Copyright (C) 2005, 2006
3 * Avishay Traeger (avishay@gmail.com)
4 * Copyright (C) 2008, 2009
5 * Boaz Harrosh <ooo@electrozaur.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
36static 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
48static 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
62static 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
77static 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 inode = exofs_new_inode(dir, mode);
84 err = PTR_ERR(inode);
85 if (!IS_ERR(inode)) {
86 init_special_inode(inode, inode->i_mode, rdev);
87 mark_inode_dirty(inode);
88 err = exofs_add_nondir(dentry, inode);
89 }
90 return err;
91}
92
93static int exofs_symlink(struct inode *dir, struct dentry *dentry,
94 const char *symname)
95{
96 struct super_block *sb = dir->i_sb;
97 int err = -ENAMETOOLONG;
98 unsigned l = strlen(symname)+1;
99 struct inode *inode;
100 struct exofs_i_info *oi;
101
102 if (l > sb->s_blocksize)
103 goto out;
104
105 inode = exofs_new_inode(dir, S_IFLNK | S_IRWXUGO);
106 err = PTR_ERR(inode);
107 if (IS_ERR(inode))
108 goto out;
109
110 oi = exofs_i(inode);
111 if (l > sizeof(oi->i_data)) {
112 /* slow symlink */
113 inode->i_op = &page_symlink_inode_operations;
114 inode_nohighmem(inode);
115 inode->i_mapping->a_ops = &exofs_aops;
116 memset(oi->i_data, 0, sizeof(oi->i_data));
117
118 err = page_symlink(inode, symname, l);
119 if (err)
120 goto out_fail;
121 } else {
122 /* fast symlink */
123 inode->i_op = &simple_symlink_inode_operations;
124 inode->i_link = (char *)oi->i_data;
125 memcpy(oi->i_data, symname, l);
126 inode->i_size = l-1;
127 }
128 mark_inode_dirty(inode);
129
130 err = exofs_add_nondir(dentry, inode);
131out:
132 return err;
133
134out_fail:
135 inode_dec_link_count(inode);
136 iput(inode);
137 goto out;
138}
139
140static int exofs_link(struct dentry *old_dentry, struct inode *dir,
141 struct dentry *dentry)
142{
143 struct inode *inode = d_inode(old_dentry);
144
145 inode->i_ctime = current_time(inode);
146 inode_inc_link_count(inode);
147 ihold(inode);
148
149 return exofs_add_nondir(dentry, inode);
150}
151
152static int exofs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
153{
154 struct inode *inode;
155 int err;
156
157 inode_inc_link_count(dir);
158
159 inode = exofs_new_inode(dir, S_IFDIR | mode);
160 err = PTR_ERR(inode);
161 if (IS_ERR(inode))
162 goto out_dir;
163
164 inode->i_op = &exofs_dir_inode_operations;
165 inode->i_fop = &exofs_dir_operations;
166 inode->i_mapping->a_ops = &exofs_aops;
167
168 inode_inc_link_count(inode);
169
170 err = exofs_make_empty(inode, dir);
171 if (err)
172 goto out_fail;
173
174 err = exofs_add_link(dentry, inode);
175 if (err)
176 goto out_fail;
177
178 d_instantiate(dentry, inode);
179out:
180 return err;
181
182out_fail:
183 inode_dec_link_count(inode);
184 inode_dec_link_count(inode);
185 iput(inode);
186out_dir:
187 inode_dec_link_count(dir);
188 goto out;
189}
190
191static int exofs_unlink(struct inode *dir, struct dentry *dentry)
192{
193 struct inode *inode = d_inode(dentry);
194 struct exofs_dir_entry *de;
195 struct page *page;
196 int err = -ENOENT;
197
198 de = exofs_find_entry(dir, dentry, &page);
199 if (!de)
200 goto out;
201
202 err = exofs_delete_entry(de, page);
203 if (err)
204 goto out;
205
206 inode->i_ctime = dir->i_ctime;
207 inode_dec_link_count(inode);
208 err = 0;
209out:
210 return err;
211}
212
213static int exofs_rmdir(struct inode *dir, struct dentry *dentry)
214{
215 struct inode *inode = d_inode(dentry);
216 int err = -ENOTEMPTY;
217
218 if (exofs_empty_dir(inode)) {
219 err = exofs_unlink(dir, dentry);
220 if (!err) {
221 inode->i_size = 0;
222 inode_dec_link_count(inode);
223 inode_dec_link_count(dir);
224 }
225 }
226 return err;
227}
228
229static int exofs_rename(struct inode *old_dir, struct dentry *old_dentry,
230 struct inode *new_dir, struct dentry *new_dentry,
231 unsigned int flags)
232{
233 struct inode *old_inode = d_inode(old_dentry);
234 struct inode *new_inode = d_inode(new_dentry);
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 if (flags & ~RENAME_NOREPLACE)
242 return -EINVAL;
243
244 old_de = exofs_find_entry(old_dir, old_dentry, &old_page);
245 if (!old_de)
246 goto out;
247
248 if (S_ISDIR(old_inode->i_mode)) {
249 err = -EIO;
250 dir_de = exofs_dotdot(old_inode, &dir_page);
251 if (!dir_de)
252 goto out_old;
253 }
254
255 if (new_inode) {
256 struct page *new_page;
257 struct exofs_dir_entry *new_de;
258
259 err = -ENOTEMPTY;
260 if (dir_de && !exofs_empty_dir(new_inode))
261 goto out_dir;
262
263 err = -ENOENT;
264 new_de = exofs_find_entry(new_dir, new_dentry, &new_page);
265 if (!new_de)
266 goto out_dir;
267 err = exofs_set_link(new_dir, new_de, new_page, old_inode);
268 new_inode->i_ctime = current_time(new_inode);
269 if (dir_de)
270 drop_nlink(new_inode);
271 inode_dec_link_count(new_inode);
272 if (err)
273 goto out_dir;
274 } else {
275 err = exofs_add_link(new_dentry, old_inode);
276 if (err)
277 goto out_dir;
278 if (dir_de)
279 inode_inc_link_count(new_dir);
280 }
281
282 old_inode->i_ctime = current_time(old_inode);
283
284 exofs_delete_entry(old_de, old_page);
285 mark_inode_dirty(old_inode);
286
287 if (dir_de) {
288 err = exofs_set_link(old_inode, dir_de, dir_page, new_dir);
289 inode_dec_link_count(old_dir);
290 if (err)
291 goto out_dir;
292 }
293 return 0;
294
295
296out_dir:
297 if (dir_de) {
298 kunmap(dir_page);
299 put_page(dir_page);
300 }
301out_old:
302 kunmap(old_page);
303 put_page(old_page);
304out:
305 return err;
306}
307
308const struct inode_operations exofs_dir_inode_operations = {
309 .create = exofs_create,
310 .lookup = exofs_lookup,
311 .link = exofs_link,
312 .unlink = exofs_unlink,
313 .symlink = exofs_symlink,
314 .mkdir = exofs_mkdir,
315 .rmdir = exofs_rmdir,
316 .mknod = exofs_mknod,
317 .rename = exofs_rename,
318 .setattr = exofs_setattr,
319};
320
321const struct inode_operations exofs_special_inode_operations = {
322 .setattr = exofs_setattr,
323};