blob: 264e95d02830f28d992eefb717460ccd0be09d4d [file] [log] [blame]
Boaz Harroshe6af00f2008-10-28 15:38:12 +02001/*
2 * Copyright (C) 2005, 2006
Boaz Harrosh27d2e142009-06-14 17:23:09 +03003 * Avishay Traeger (avishay@gmail.com)
Boaz Harroshe6af00f2008-10-28 15:38:12 +02004 * 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
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 struct nameidata *nd)
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 = NULL;
59 if (ino) {
60 inode = exofs_iget(dir->i_sb, ino);
61 if (IS_ERR(inode))
62 return ERR_CAST(inode);
63 }
64 return d_splice_alias(inode, dentry);
65}
66
67static int exofs_create(struct inode *dir, struct dentry *dentry, int mode,
68 struct nameidata *nd)
69{
70 struct inode *inode = exofs_new_inode(dir, mode);
71 int err = PTR_ERR(inode);
72 if (!IS_ERR(inode)) {
73 inode->i_op = &exofs_file_inode_operations;
74 inode->i_fop = &exofs_file_operations;
75 inode->i_mapping->a_ops = &exofs_aops;
76 mark_inode_dirty(inode);
77 err = exofs_add_nondir(dentry, inode);
78 }
79 return err;
80}
81
82static int exofs_mknod(struct inode *dir, struct dentry *dentry, int mode,
83 dev_t rdev)
84{
85 struct inode *inode;
86 int err;
87
88 if (!new_valid_dev(rdev))
89 return -EINVAL;
90
91 inode = exofs_new_inode(dir, mode);
92 err = PTR_ERR(inode);
93 if (!IS_ERR(inode)) {
94 init_special_inode(inode, inode->i_mode, rdev);
95 mark_inode_dirty(inode);
96 err = exofs_add_nondir(dentry, inode);
97 }
98 return err;
99}
100
101static int exofs_symlink(struct inode *dir, struct dentry *dentry,
102 const char *symname)
103{
104 struct super_block *sb = dir->i_sb;
105 int err = -ENAMETOOLONG;
106 unsigned l = strlen(symname)+1;
107 struct inode *inode;
108 struct exofs_i_info *oi;
109
110 if (l > sb->s_blocksize)
111 goto out;
112
113 inode = exofs_new_inode(dir, S_IFLNK | S_IRWXUGO);
114 err = PTR_ERR(inode);
115 if (IS_ERR(inode))
116 goto out;
117
118 oi = exofs_i(inode);
119 if (l > sizeof(oi->i_data)) {
120 /* slow symlink */
121 inode->i_op = &exofs_symlink_inode_operations;
122 inode->i_mapping->a_ops = &exofs_aops;
123 memset(oi->i_data, 0, sizeof(oi->i_data));
124
125 err = page_symlink(inode, symname, l);
126 if (err)
127 goto out_fail;
128 } else {
129 /* fast symlink */
130 inode->i_op = &exofs_fast_symlink_inode_operations;
131 memcpy(oi->i_data, symname, l);
132 inode->i_size = l-1;
133 }
134 mark_inode_dirty(inode);
135
136 err = exofs_add_nondir(dentry, inode);
137out:
138 return err;
139
140out_fail:
141 inode_dec_link_count(inode);
142 iput(inode);
143 goto out;
144}
145
146static int exofs_link(struct dentry *old_dentry, struct inode *dir,
147 struct dentry *dentry)
148{
149 struct inode *inode = old_dentry->d_inode;
150
151 if (inode->i_nlink >= EXOFS_LINK_MAX)
152 return -EMLINK;
153
154 inode->i_ctime = CURRENT_TIME;
155 inode_inc_link_count(inode);
Al Viro7de9c6ee2010-10-23 11:11:40 -0400156 ihold(inode);
Boaz Harroshe6af00f2008-10-28 15:38:12 +0200157
158 return exofs_add_nondir(dentry, inode);
159}
160
161static int exofs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
162{
163 struct inode *inode;
164 int err = -EMLINK;
165
166 if (dir->i_nlink >= EXOFS_LINK_MAX)
167 goto out;
168
169 inode_inc_link_count(dir);
170
171 inode = exofs_new_inode(dir, S_IFDIR | mode);
172 err = PTR_ERR(inode);
173 if (IS_ERR(inode))
174 goto out_dir;
175
176 inode->i_op = &exofs_dir_inode_operations;
177 inode->i_fop = &exofs_dir_operations;
178 inode->i_mapping->a_ops = &exofs_aops;
179
180 inode_inc_link_count(inode);
181
182 err = exofs_make_empty(inode, dir);
183 if (err)
184 goto out_fail;
185
186 err = exofs_add_link(dentry, inode);
187 if (err)
188 goto out_fail;
189
190 d_instantiate(dentry, inode);
191out:
192 return err;
193
194out_fail:
195 inode_dec_link_count(inode);
196 inode_dec_link_count(inode);
197 iput(inode);
198out_dir:
199 inode_dec_link_count(dir);
200 goto out;
201}
202
203static int exofs_unlink(struct inode *dir, struct dentry *dentry)
204{
205 struct inode *inode = dentry->d_inode;
206 struct exofs_dir_entry *de;
207 struct page *page;
208 int err = -ENOENT;
209
210 de = exofs_find_entry(dir, dentry, &page);
211 if (!de)
212 goto out;
213
214 err = exofs_delete_entry(de, page);
215 if (err)
216 goto out;
217
218 inode->i_ctime = dir->i_ctime;
219 inode_dec_link_count(inode);
220 err = 0;
221out:
222 return err;
223}
224
225static int exofs_rmdir(struct inode *dir, struct dentry *dentry)
226{
227 struct inode *inode = dentry->d_inode;
228 int err = -ENOTEMPTY;
229
230 if (exofs_empty_dir(inode)) {
231 err = exofs_unlink(dir, dentry);
232 if (!err) {
233 inode->i_size = 0;
234 inode_dec_link_count(inode);
235 inode_dec_link_count(dir);
236 }
237 }
238 return err;
239}
240
241static int exofs_rename(struct inode *old_dir, struct dentry *old_dentry,
242 struct inode *new_dir, struct dentry *new_dentry)
243{
244 struct inode *old_inode = old_dentry->d_inode;
245 struct inode *new_inode = new_dentry->d_inode;
246 struct page *dir_page = NULL;
247 struct exofs_dir_entry *dir_de = NULL;
248 struct page *old_page;
249 struct exofs_dir_entry *old_de;
250 int err = -ENOENT;
251
252 old_de = exofs_find_entry(old_dir, old_dentry, &old_page);
253 if (!old_de)
254 goto out;
255
256 if (S_ISDIR(old_inode->i_mode)) {
257 err = -EIO;
258 dir_de = exofs_dotdot(old_inode, &dir_page);
259 if (!dir_de)
260 goto out_old;
261 }
262
263 if (new_inode) {
264 struct page *new_page;
265 struct exofs_dir_entry *new_de;
266
267 err = -ENOTEMPTY;
268 if (dir_de && !exofs_empty_dir(new_inode))
269 goto out_dir;
270
271 err = -ENOENT;
272 new_de = exofs_find_entry(new_dir, new_dentry, &new_page);
273 if (!new_de)
274 goto out_dir;
275 inode_inc_link_count(old_inode);
276 err = exofs_set_link(new_dir, new_de, new_page, old_inode);
277 new_inode->i_ctime = CURRENT_TIME;
278 if (dir_de)
279 drop_nlink(new_inode);
280 inode_dec_link_count(new_inode);
281 if (err)
282 goto out_dir;
283 } else {
284 if (dir_de) {
285 err = -EMLINK;
286 if (new_dir->i_nlink >= EXOFS_LINK_MAX)
287 goto out_dir;
288 }
289 inode_inc_link_count(old_inode);
290 err = exofs_add_link(new_dentry, old_inode);
291 if (err) {
292 inode_dec_link_count(old_inode);
293 goto out_dir;
294 }
295 if (dir_de)
296 inode_inc_link_count(new_dir);
297 }
298
299 old_inode->i_ctime = CURRENT_TIME;
300
301 exofs_delete_entry(old_de, old_page);
302 inode_dec_link_count(old_inode);
303
304 if (dir_de) {
305 err = exofs_set_link(old_inode, dir_de, dir_page, new_dir);
306 inode_dec_link_count(old_dir);
307 if (err)
308 goto out_dir;
309 }
310 return 0;
311
312
313out_dir:
314 if (dir_de) {
315 kunmap(dir_page);
316 page_cache_release(dir_page);
317 }
318out_old:
319 kunmap(old_page);
320 page_cache_release(old_page);
321out:
322 return err;
323}
324
325const struct inode_operations exofs_dir_inode_operations = {
326 .create = exofs_create,
327 .lookup = exofs_lookup,
328 .link = exofs_link,
329 .unlink = exofs_unlink,
330 .symlink = exofs_symlink,
331 .mkdir = exofs_mkdir,
332 .rmdir = exofs_rmdir,
333 .mknod = exofs_mknod,
334 .rename = exofs_rename,
335 .setattr = exofs_setattr,
336};
337
338const struct inode_operations exofs_special_inode_operations = {
339 .setattr = exofs_setattr,
340};