]>
Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * linux/fs/ext2/namei.c | |
3 | * | |
4 | * Rewrite to pagecache. Almost all code had been changed, so blame me | |
5 | * if the things go wrong. Please, send bug reports to | |
6 | * viro@parcelfarce.linux.theplanet.co.uk | |
7 | * | |
8 | * Stuff here is basically a glue between the VFS and generic UNIXish | |
9 | * filesystem that keeps everything in pagecache. All knowledge of the | |
10 | * directory layout is in fs/ext2/dir.c - it turned out to be easily separatable | |
11 | * and it's easier to debug that way. In principle we might want to | |
12 | * generalize that a bit and turn it into a library. Or not. | |
13 | * | |
14 | * The only non-static object here is ext2_dir_inode_operations. | |
15 | * | |
16 | * TODO: get rid of kmap() use, add readahead. | |
17 | * | |
18 | * Copyright (C) 1992, 1993, 1994, 1995 | |
19 | * Remy Card (card@masi.ibp.fr) | |
20 | * Laboratoire MASI - Institut Blaise Pascal | |
21 | * Universite Pierre et Marie Curie (Paris VI) | |
22 | * | |
23 | * from | |
24 | * | |
25 | * linux/fs/minix/namei.c | |
26 | * | |
27 | * Copyright (C) 1991, 1992 Linus Torvalds | |
28 | * | |
29 | * Big-endian to little-endian byte-swapping/bitmaps by | |
30 | * David S. Miller (davem@caip.rutgers.edu), 1995 | |
31 | */ | |
32 | ||
33 | #include <linux/pagemap.h> | |
907f4554 | 34 | #include <linux/quotaops.h> |
1da177e4 LT |
35 | #include "ext2.h" |
36 | #include "xattr.h" | |
37 | #include "acl.h" | |
38 | ||
1da177e4 LT |
39 | static inline int ext2_add_nondir(struct dentry *dentry, struct inode *inode) |
40 | { | |
41 | int err = ext2_add_link(dentry, inode); | |
42 | if (!err) { | |
41080b5a | 43 | unlock_new_inode(inode); |
8fc37ec5 | 44 | d_instantiate(dentry, inode); |
1da177e4 LT |
45 | return 0; |
46 | } | |
a513b035 | 47 | inode_dec_link_count(inode); |
41080b5a | 48 | unlock_new_inode(inode); |
1da177e4 LT |
49 | iput(inode); |
50 | return err; | |
51 | } | |
52 | ||
53 | /* | |
54 | * Methods themselves. | |
55 | */ | |
56 | ||
00cd8dd3 | 57 | static struct dentry *ext2_lookup(struct inode * dir, struct dentry *dentry, unsigned int flags) |
1da177e4 LT |
58 | { |
59 | struct inode * inode; | |
60 | ino_t ino; | |
61 | ||
62 | if (dentry->d_name.len > EXT2_NAME_LEN) | |
63 | return ERR_PTR(-ENAMETOOLONG); | |
64 | ||
a9885444 | 65 | ino = ext2_inode_by_name(dir, &dentry->d_name); |
1da177e4 LT |
66 | inode = NULL; |
67 | if (ino) { | |
52fcf703 | 68 | inode = ext2_iget(dir->i_sb, ino); |
a9049376 AV |
69 | if (inode == ERR_PTR(-ESTALE)) { |
70 | ext2_error(dir->i_sb, __func__, | |
71 | "deleted inode referenced: %lu", | |
72 | (unsigned long) ino); | |
73 | return ERR_PTR(-EIO); | |
4d6c13f8 | 74 | } |
1da177e4 | 75 | } |
082a05c6 | 76 | return d_splice_alias(inode, dentry); |
1da177e4 LT |
77 | } |
78 | ||
79 | struct dentry *ext2_get_parent(struct dentry *child) | |
80 | { | |
26fe5750 | 81 | struct qstr dotdot = QSTR_INIT("..", 2); |
a9885444 | 82 | unsigned long ino = ext2_inode_by_name(child->d_inode, &dotdot); |
1da177e4 LT |
83 | if (!ino) |
84 | return ERR_PTR(-ENOENT); | |
44003728 | 85 | return d_obtain_alias(ext2_iget(child->d_inode->i_sb, ino)); |
1da177e4 LT |
86 | } |
87 | ||
88 | /* | |
89 | * By the time this is called, we already have created | |
90 | * the directory cache entry for the new file, but it | |
91 | * is so far negative - it has no inode. | |
92 | * | |
93 | * If the create succeeds, we fill in the inode information | |
94 | * with d_instantiate(). | |
95 | */ | |
ebfc3b49 | 96 | static int ext2_create (struct inode * dir, struct dentry * dentry, umode_t mode, bool excl) |
1da177e4 | 97 | { |
907f4554 CH |
98 | struct inode *inode; |
99 | ||
871a2931 | 100 | dquot_initialize(dir); |
907f4554 | 101 | |
2a7dba39 | 102 | inode = ext2_new_inode(dir, mode, &dentry->d_name); |
907f4554 CH |
103 | if (IS_ERR(inode)) |
104 | return PTR_ERR(inode); | |
105 | ||
106 | inode->i_op = &ext2_file_inode_operations; | |
be64f884 | 107 | if (test_opt(inode->i_sb, NOBH)) { |
907f4554 CH |
108 | inode->i_mapping->a_ops = &ext2_nobh_aops; |
109 | inode->i_fop = &ext2_file_operations; | |
110 | } else { | |
111 | inode->i_mapping->a_ops = &ext2_aops; | |
112 | inode->i_fop = &ext2_file_operations; | |
1da177e4 | 113 | } |
907f4554 CH |
114 | mark_inode_dirty(inode); |
115 | return ext2_add_nondir(dentry, inode); | |
1da177e4 LT |
116 | } |
117 | ||
60545d0d AV |
118 | static int ext2_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode) |
119 | { | |
120 | struct inode *inode = ext2_new_inode(dir, mode, NULL); | |
121 | if (IS_ERR(inode)) | |
122 | return PTR_ERR(inode); | |
123 | ||
124 | inode->i_op = &ext2_file_inode_operations; | |
be64f884 | 125 | if (test_opt(inode->i_sb, NOBH)) { |
60545d0d AV |
126 | inode->i_mapping->a_ops = &ext2_nobh_aops; |
127 | inode->i_fop = &ext2_file_operations; | |
128 | } else { | |
129 | inode->i_mapping->a_ops = &ext2_aops; | |
130 | inode->i_fop = &ext2_file_operations; | |
131 | } | |
132 | mark_inode_dirty(inode); | |
133 | d_tmpfile(dentry, inode); | |
134 | unlock_new_inode(inode); | |
135 | return 0; | |
136 | } | |
137 | ||
1a67aafb | 138 | static int ext2_mknod (struct inode * dir, struct dentry *dentry, umode_t mode, dev_t rdev) |
1da177e4 LT |
139 | { |
140 | struct inode * inode; | |
141 | int err; | |
142 | ||
143 | if (!new_valid_dev(rdev)) | |
144 | return -EINVAL; | |
145 | ||
871a2931 | 146 | dquot_initialize(dir); |
907f4554 | 147 | |
2a7dba39 | 148 | inode = ext2_new_inode (dir, mode, &dentry->d_name); |
1da177e4 LT |
149 | err = PTR_ERR(inode); |
150 | if (!IS_ERR(inode)) { | |
151 | init_special_inode(inode, inode->i_mode, rdev); | |
152 | #ifdef CONFIG_EXT2_FS_XATTR | |
153 | inode->i_op = &ext2_special_inode_operations; | |
154 | #endif | |
155 | mark_inode_dirty(inode); | |
156 | err = ext2_add_nondir(dentry, inode); | |
157 | } | |
158 | return err; | |
159 | } | |
160 | ||
161 | static int ext2_symlink (struct inode * dir, struct dentry * dentry, | |
162 | const char * symname) | |
163 | { | |
164 | struct super_block * sb = dir->i_sb; | |
165 | int err = -ENAMETOOLONG; | |
166 | unsigned l = strlen(symname)+1; | |
167 | struct inode * inode; | |
168 | ||
169 | if (l > sb->s_blocksize) | |
170 | goto out; | |
171 | ||
871a2931 | 172 | dquot_initialize(dir); |
907f4554 | 173 | |
2a7dba39 | 174 | inode = ext2_new_inode (dir, S_IFLNK | S_IRWXUGO, &dentry->d_name); |
1da177e4 LT |
175 | err = PTR_ERR(inode); |
176 | if (IS_ERR(inode)) | |
177 | goto out; | |
178 | ||
179 | if (l > sizeof (EXT2_I(inode)->i_data)) { | |
180 | /* slow symlink */ | |
181 | inode->i_op = &ext2_symlink_inode_operations; | |
182 | if (test_opt(inode->i_sb, NOBH)) | |
183 | inode->i_mapping->a_ops = &ext2_nobh_aops; | |
184 | else | |
185 | inode->i_mapping->a_ops = &ext2_aops; | |
186 | err = page_symlink(inode, symname, l); | |
187 | if (err) | |
188 | goto out_fail; | |
189 | } else { | |
190 | /* fast symlink */ | |
191 | inode->i_op = &ext2_fast_symlink_inode_operations; | |
192 | memcpy((char*)(EXT2_I(inode)->i_data),symname,l); | |
193 | inode->i_size = l-1; | |
194 | } | |
195 | mark_inode_dirty(inode); | |
196 | ||
197 | err = ext2_add_nondir(dentry, inode); | |
198 | out: | |
199 | return err; | |
200 | ||
201 | out_fail: | |
a513b035 | 202 | inode_dec_link_count(inode); |
41080b5a | 203 | unlock_new_inode(inode); |
1da177e4 LT |
204 | iput (inode); |
205 | goto out; | |
206 | } | |
207 | ||
208 | static int ext2_link (struct dentry * old_dentry, struct inode * dir, | |
209 | struct dentry *dentry) | |
210 | { | |
211 | struct inode *inode = old_dentry->d_inode; | |
41080b5a | 212 | int err; |
1da177e4 | 213 | |
871a2931 | 214 | dquot_initialize(dir); |
907f4554 | 215 | |
1da177e4 | 216 | inode->i_ctime = CURRENT_TIME_SEC; |
a513b035 | 217 | inode_inc_link_count(inode); |
7de9c6ee | 218 | ihold(inode); |
1da177e4 | 219 | |
41080b5a AV |
220 | err = ext2_add_link(dentry, inode); |
221 | if (!err) { | |
222 | d_instantiate(dentry, inode); | |
223 | return 0; | |
224 | } | |
225 | inode_dec_link_count(inode); | |
226 | iput(inode); | |
227 | return err; | |
1da177e4 LT |
228 | } |
229 | ||
18bb1db3 | 230 | static int ext2_mkdir(struct inode * dir, struct dentry * dentry, umode_t mode) |
1da177e4 LT |
231 | { |
232 | struct inode * inode; | |
8de52778 | 233 | int err; |
1da177e4 | 234 | |
871a2931 | 235 | dquot_initialize(dir); |
907f4554 | 236 | |
a513b035 | 237 | inode_inc_link_count(dir); |
1da177e4 | 238 | |
2a7dba39 | 239 | inode = ext2_new_inode(dir, S_IFDIR | mode, &dentry->d_name); |
1da177e4 LT |
240 | err = PTR_ERR(inode); |
241 | if (IS_ERR(inode)) | |
242 | goto out_dir; | |
243 | ||
244 | inode->i_op = &ext2_dir_inode_operations; | |
245 | inode->i_fop = &ext2_dir_operations; | |
246 | if (test_opt(inode->i_sb, NOBH)) | |
247 | inode->i_mapping->a_ops = &ext2_nobh_aops; | |
248 | else | |
249 | inode->i_mapping->a_ops = &ext2_aops; | |
250 | ||
a513b035 | 251 | inode_inc_link_count(inode); |
1da177e4 LT |
252 | |
253 | err = ext2_make_empty(inode, dir); | |
254 | if (err) | |
255 | goto out_fail; | |
256 | ||
257 | err = ext2_add_link(dentry, inode); | |
258 | if (err) | |
259 | goto out_fail; | |
260 | ||
41080b5a | 261 | unlock_new_inode(inode); |
8fc37ec5 | 262 | d_instantiate(dentry, inode); |
1da177e4 LT |
263 | out: |
264 | return err; | |
265 | ||
266 | out_fail: | |
a513b035 AD |
267 | inode_dec_link_count(inode); |
268 | inode_dec_link_count(inode); | |
41080b5a | 269 | unlock_new_inode(inode); |
1da177e4 LT |
270 | iput(inode); |
271 | out_dir: | |
a513b035 | 272 | inode_dec_link_count(dir); |
1da177e4 LT |
273 | goto out; |
274 | } | |
275 | ||
276 | static int ext2_unlink(struct inode * dir, struct dentry *dentry) | |
277 | { | |
278 | struct inode * inode = dentry->d_inode; | |
279 | struct ext2_dir_entry_2 * de; | |
280 | struct page * page; | |
281 | int err = -ENOENT; | |
282 | ||
871a2931 | 283 | dquot_initialize(dir); |
907f4554 | 284 | |
a9885444 | 285 | de = ext2_find_entry (dir, &dentry->d_name, &page); |
1da177e4 LT |
286 | if (!de) |
287 | goto out; | |
288 | ||
289 | err = ext2_delete_entry (de, page); | |
290 | if (err) | |
291 | goto out; | |
292 | ||
293 | inode->i_ctime = dir->i_ctime; | |
a513b035 | 294 | inode_dec_link_count(inode); |
1da177e4 LT |
295 | err = 0; |
296 | out: | |
297 | return err; | |
298 | } | |
299 | ||
300 | static int ext2_rmdir (struct inode * dir, struct dentry *dentry) | |
301 | { | |
302 | struct inode * inode = dentry->d_inode; | |
303 | int err = -ENOTEMPTY; | |
304 | ||
305 | if (ext2_empty_dir(inode)) { | |
306 | err = ext2_unlink(dir, dentry); | |
307 | if (!err) { | |
308 | inode->i_size = 0; | |
a513b035 AD |
309 | inode_dec_link_count(inode); |
310 | inode_dec_link_count(dir); | |
1da177e4 LT |
311 | } |
312 | } | |
313 | return err; | |
314 | } | |
315 | ||
316 | static int ext2_rename (struct inode * old_dir, struct dentry * old_dentry, | |
317 | struct inode * new_dir, struct dentry * new_dentry ) | |
318 | { | |
319 | struct inode * old_inode = old_dentry->d_inode; | |
320 | struct inode * new_inode = new_dentry->d_inode; | |
321 | struct page * dir_page = NULL; | |
322 | struct ext2_dir_entry_2 * dir_de = NULL; | |
323 | struct page * old_page; | |
324 | struct ext2_dir_entry_2 * old_de; | |
325 | int err = -ENOENT; | |
326 | ||
871a2931 CH |
327 | dquot_initialize(old_dir); |
328 | dquot_initialize(new_dir); | |
907f4554 | 329 | |
a9885444 | 330 | old_de = ext2_find_entry (old_dir, &old_dentry->d_name, &old_page); |
1da177e4 LT |
331 | if (!old_de) |
332 | goto out; | |
333 | ||
334 | if (S_ISDIR(old_inode->i_mode)) { | |
335 | err = -EIO; | |
336 | dir_de = ext2_dotdot(old_inode, &dir_page); | |
337 | if (!dir_de) | |
338 | goto out_old; | |
339 | } | |
340 | ||
341 | if (new_inode) { | |
342 | struct page *new_page; | |
343 | struct ext2_dir_entry_2 *new_de; | |
344 | ||
345 | err = -ENOTEMPTY; | |
346 | if (dir_de && !ext2_empty_dir (new_inode)) | |
347 | goto out_dir; | |
348 | ||
349 | err = -ENOENT; | |
a9885444 | 350 | new_de = ext2_find_entry (new_dir, &new_dentry->d_name, &new_page); |
1da177e4 LT |
351 | if (!new_de) |
352 | goto out_dir; | |
39fe7557 | 353 | ext2_set_link(new_dir, new_de, new_page, old_inode, 1); |
1da177e4 LT |
354 | new_inode->i_ctime = CURRENT_TIME_SEC; |
355 | if (dir_de) | |
9a53c3a7 | 356 | drop_nlink(new_inode); |
a513b035 | 357 | inode_dec_link_count(new_inode); |
1da177e4 | 358 | } else { |
1da177e4 | 359 | err = ext2_add_link(new_dentry, old_inode); |
e8a80c6f | 360 | if (err) |
1da177e4 | 361 | goto out_dir; |
1da177e4 | 362 | if (dir_de) |
a513b035 | 363 | inode_inc_link_count(new_dir); |
1da177e4 LT |
364 | } |
365 | ||
366 | /* | |
367 | * Like most other Unix systems, set the ctime for inodes on a | |
368 | * rename. | |
1da177e4 LT |
369 | */ |
370 | old_inode->i_ctime = CURRENT_TIME_SEC; | |
e8a80c6f | 371 | mark_inode_dirty(old_inode); |
1da177e4 LT |
372 | |
373 | ext2_delete_entry (old_de, old_page); | |
1da177e4 LT |
374 | |
375 | if (dir_de) { | |
39fe7557 JK |
376 | if (old_dir != new_dir) |
377 | ext2_set_link(old_inode, dir_de, dir_page, new_dir, 0); | |
9de6886e NP |
378 | else { |
379 | kunmap(dir_page); | |
380 | page_cache_release(dir_page); | |
381 | } | |
a513b035 | 382 | inode_dec_link_count(old_dir); |
1da177e4 LT |
383 | } |
384 | return 0; | |
385 | ||
386 | ||
387 | out_dir: | |
388 | if (dir_de) { | |
389 | kunmap(dir_page); | |
390 | page_cache_release(dir_page); | |
391 | } | |
392 | out_old: | |
393 | kunmap(old_page); | |
394 | page_cache_release(old_page); | |
395 | out: | |
396 | return err; | |
397 | } | |
398 | ||
754661f1 | 399 | const struct inode_operations ext2_dir_inode_operations = { |
1da177e4 LT |
400 | .create = ext2_create, |
401 | .lookup = ext2_lookup, | |
402 | .link = ext2_link, | |
403 | .unlink = ext2_unlink, | |
404 | .symlink = ext2_symlink, | |
405 | .mkdir = ext2_mkdir, | |
406 | .rmdir = ext2_rmdir, | |
407 | .mknod = ext2_mknod, | |
408 | .rename = ext2_rename, | |
409 | #ifdef CONFIG_EXT2_FS_XATTR | |
410 | .setxattr = generic_setxattr, | |
411 | .getxattr = generic_getxattr, | |
412 | .listxattr = ext2_listxattr, | |
413 | .removexattr = generic_removexattr, | |
414 | #endif | |
415 | .setattr = ext2_setattr, | |
4e34e719 | 416 | .get_acl = ext2_get_acl, |
64e178a7 | 417 | .set_acl = ext2_set_acl, |
60545d0d | 418 | .tmpfile = ext2_tmpfile, |
1da177e4 LT |
419 | }; |
420 | ||
754661f1 | 421 | const struct inode_operations ext2_special_inode_operations = { |
1da177e4 LT |
422 | #ifdef CONFIG_EXT2_FS_XATTR |
423 | .setxattr = generic_setxattr, | |
424 | .getxattr = generic_getxattr, | |
425 | .listxattr = ext2_listxattr, | |
426 | .removexattr = generic_removexattr, | |
427 | #endif | |
428 | .setattr = ext2_setattr, | |
4e34e719 | 429 | .get_acl = ext2_get_acl, |
64e178a7 | 430 | .set_acl = ext2_set_acl, |
1da177e4 | 431 | }; |