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Commit | Line | Data |
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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); |
2b0143b5 | 82 | unsigned long ino = ext2_inode_by_name(d_inode(child), &dotdot); |
1da177e4 LT |
83 | if (!ino) |
84 | return ERR_PTR(-ENOENT); | |
2b0143b5 | 85 | return d_obtain_alias(ext2_iget(d_inode(child)->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 | 98 | struct inode *inode; |
c2edb305 | 99 | int err; |
907f4554 | 100 | |
c2edb305 JK |
101 | err = dquot_initialize(dir); |
102 | if (err) | |
103 | return err; | |
907f4554 | 104 | |
2a7dba39 | 105 | inode = ext2_new_inode(dir, mode, &dentry->d_name); |
907f4554 CH |
106 | if (IS_ERR(inode)) |
107 | return PTR_ERR(inode); | |
108 | ||
109 | inode->i_op = &ext2_file_inode_operations; | |
be64f884 | 110 | if (test_opt(inode->i_sb, NOBH)) { |
907f4554 CH |
111 | inode->i_mapping->a_ops = &ext2_nobh_aops; |
112 | inode->i_fop = &ext2_file_operations; | |
113 | } else { | |
114 | inode->i_mapping->a_ops = &ext2_aops; | |
115 | inode->i_fop = &ext2_file_operations; | |
1da177e4 | 116 | } |
907f4554 CH |
117 | mark_inode_dirty(inode); |
118 | return ext2_add_nondir(dentry, inode); | |
1da177e4 LT |
119 | } |
120 | ||
60545d0d AV |
121 | static int ext2_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode) |
122 | { | |
123 | struct inode *inode = ext2_new_inode(dir, mode, NULL); | |
124 | if (IS_ERR(inode)) | |
125 | return PTR_ERR(inode); | |
126 | ||
127 | inode->i_op = &ext2_file_inode_operations; | |
be64f884 | 128 | if (test_opt(inode->i_sb, NOBH)) { |
60545d0d AV |
129 | inode->i_mapping->a_ops = &ext2_nobh_aops; |
130 | inode->i_fop = &ext2_file_operations; | |
131 | } else { | |
132 | inode->i_mapping->a_ops = &ext2_aops; | |
133 | inode->i_fop = &ext2_file_operations; | |
134 | } | |
135 | mark_inode_dirty(inode); | |
136 | d_tmpfile(dentry, inode); | |
137 | unlock_new_inode(inode); | |
138 | return 0; | |
139 | } | |
140 | ||
1a67aafb | 141 | static int ext2_mknod (struct inode * dir, struct dentry *dentry, umode_t mode, dev_t rdev) |
1da177e4 LT |
142 | { |
143 | struct inode * inode; | |
144 | int err; | |
145 | ||
146 | if (!new_valid_dev(rdev)) | |
147 | return -EINVAL; | |
148 | ||
c2edb305 JK |
149 | err = dquot_initialize(dir); |
150 | if (err) | |
151 | return err; | |
907f4554 | 152 | |
2a7dba39 | 153 | inode = ext2_new_inode (dir, mode, &dentry->d_name); |
1da177e4 LT |
154 | err = PTR_ERR(inode); |
155 | if (!IS_ERR(inode)) { | |
156 | init_special_inode(inode, inode->i_mode, rdev); | |
157 | #ifdef CONFIG_EXT2_FS_XATTR | |
158 | inode->i_op = &ext2_special_inode_operations; | |
159 | #endif | |
160 | mark_inode_dirty(inode); | |
161 | err = ext2_add_nondir(dentry, inode); | |
162 | } | |
163 | return err; | |
164 | } | |
165 | ||
166 | static int ext2_symlink (struct inode * dir, struct dentry * dentry, | |
167 | const char * symname) | |
168 | { | |
169 | struct super_block * sb = dir->i_sb; | |
170 | int err = -ENAMETOOLONG; | |
171 | unsigned l = strlen(symname)+1; | |
172 | struct inode * inode; | |
173 | ||
174 | if (l > sb->s_blocksize) | |
175 | goto out; | |
176 | ||
c2edb305 JK |
177 | err = dquot_initialize(dir); |
178 | if (err) | |
179 | goto out; | |
907f4554 | 180 | |
2a7dba39 | 181 | inode = ext2_new_inode (dir, S_IFLNK | S_IRWXUGO, &dentry->d_name); |
1da177e4 LT |
182 | err = PTR_ERR(inode); |
183 | if (IS_ERR(inode)) | |
184 | goto out; | |
185 | ||
186 | if (l > sizeof (EXT2_I(inode)->i_data)) { | |
187 | /* slow symlink */ | |
188 | inode->i_op = &ext2_symlink_inode_operations; | |
189 | if (test_opt(inode->i_sb, NOBH)) | |
190 | inode->i_mapping->a_ops = &ext2_nobh_aops; | |
191 | else | |
192 | inode->i_mapping->a_ops = &ext2_aops; | |
193 | err = page_symlink(inode, symname, l); | |
194 | if (err) | |
195 | goto out_fail; | |
196 | } else { | |
197 | /* fast symlink */ | |
198 | inode->i_op = &ext2_fast_symlink_inode_operations; | |
cbe0fa38 AV |
199 | inode->i_link = (char*)EXT2_I(inode)->i_data; |
200 | memcpy(inode->i_link, symname, l); | |
1da177e4 LT |
201 | inode->i_size = l-1; |
202 | } | |
203 | mark_inode_dirty(inode); | |
204 | ||
205 | err = ext2_add_nondir(dentry, inode); | |
206 | out: | |
207 | return err; | |
208 | ||
209 | out_fail: | |
a513b035 | 210 | inode_dec_link_count(inode); |
41080b5a | 211 | unlock_new_inode(inode); |
1da177e4 LT |
212 | iput (inode); |
213 | goto out; | |
214 | } | |
215 | ||
216 | static int ext2_link (struct dentry * old_dentry, struct inode * dir, | |
217 | struct dentry *dentry) | |
218 | { | |
2b0143b5 | 219 | struct inode *inode = d_inode(old_dentry); |
41080b5a | 220 | int err; |
1da177e4 | 221 | |
c2edb305 JK |
222 | err = dquot_initialize(dir); |
223 | if (err) | |
224 | return err; | |
907f4554 | 225 | |
1da177e4 | 226 | inode->i_ctime = CURRENT_TIME_SEC; |
a513b035 | 227 | inode_inc_link_count(inode); |
7de9c6ee | 228 | ihold(inode); |
1da177e4 | 229 | |
41080b5a AV |
230 | err = ext2_add_link(dentry, inode); |
231 | if (!err) { | |
232 | d_instantiate(dentry, inode); | |
233 | return 0; | |
234 | } | |
235 | inode_dec_link_count(inode); | |
236 | iput(inode); | |
237 | return err; | |
1da177e4 LT |
238 | } |
239 | ||
18bb1db3 | 240 | static int ext2_mkdir(struct inode * dir, struct dentry * dentry, umode_t mode) |
1da177e4 LT |
241 | { |
242 | struct inode * inode; | |
8de52778 | 243 | int err; |
1da177e4 | 244 | |
c2edb305 JK |
245 | err = dquot_initialize(dir); |
246 | if (err) | |
247 | return err; | |
907f4554 | 248 | |
a513b035 | 249 | inode_inc_link_count(dir); |
1da177e4 | 250 | |
2a7dba39 | 251 | inode = ext2_new_inode(dir, S_IFDIR | mode, &dentry->d_name); |
1da177e4 LT |
252 | err = PTR_ERR(inode); |
253 | if (IS_ERR(inode)) | |
254 | goto out_dir; | |
255 | ||
256 | inode->i_op = &ext2_dir_inode_operations; | |
257 | inode->i_fop = &ext2_dir_operations; | |
258 | if (test_opt(inode->i_sb, NOBH)) | |
259 | inode->i_mapping->a_ops = &ext2_nobh_aops; | |
260 | else | |
261 | inode->i_mapping->a_ops = &ext2_aops; | |
262 | ||
a513b035 | 263 | inode_inc_link_count(inode); |
1da177e4 LT |
264 | |
265 | err = ext2_make_empty(inode, dir); | |
266 | if (err) | |
267 | goto out_fail; | |
268 | ||
269 | err = ext2_add_link(dentry, inode); | |
270 | if (err) | |
271 | goto out_fail; | |
272 | ||
41080b5a | 273 | unlock_new_inode(inode); |
8fc37ec5 | 274 | d_instantiate(dentry, inode); |
1da177e4 LT |
275 | out: |
276 | return err; | |
277 | ||
278 | out_fail: | |
a513b035 AD |
279 | inode_dec_link_count(inode); |
280 | inode_dec_link_count(inode); | |
41080b5a | 281 | unlock_new_inode(inode); |
1da177e4 LT |
282 | iput(inode); |
283 | out_dir: | |
a513b035 | 284 | inode_dec_link_count(dir); |
1da177e4 LT |
285 | goto out; |
286 | } | |
287 | ||
288 | static int ext2_unlink(struct inode * dir, struct dentry *dentry) | |
289 | { | |
2b0143b5 | 290 | struct inode * inode = d_inode(dentry); |
1da177e4 LT |
291 | struct ext2_dir_entry_2 * de; |
292 | struct page * page; | |
c2edb305 | 293 | int err; |
1da177e4 | 294 | |
c2edb305 JK |
295 | err = dquot_initialize(dir); |
296 | if (err) | |
297 | goto out; | |
907f4554 | 298 | |
a9885444 | 299 | de = ext2_find_entry (dir, &dentry->d_name, &page); |
c2edb305 JK |
300 | if (!de) { |
301 | err = -ENOENT; | |
1da177e4 | 302 | goto out; |
c2edb305 | 303 | } |
1da177e4 LT |
304 | |
305 | err = ext2_delete_entry (de, page); | |
306 | if (err) | |
307 | goto out; | |
308 | ||
309 | inode->i_ctime = dir->i_ctime; | |
a513b035 | 310 | inode_dec_link_count(inode); |
1da177e4 LT |
311 | err = 0; |
312 | out: | |
313 | return err; | |
314 | } | |
315 | ||
316 | static int ext2_rmdir (struct inode * dir, struct dentry *dentry) | |
317 | { | |
2b0143b5 | 318 | struct inode * inode = d_inode(dentry); |
1da177e4 LT |
319 | int err = -ENOTEMPTY; |
320 | ||
321 | if (ext2_empty_dir(inode)) { | |
322 | err = ext2_unlink(dir, dentry); | |
323 | if (!err) { | |
324 | inode->i_size = 0; | |
a513b035 AD |
325 | inode_dec_link_count(inode); |
326 | inode_dec_link_count(dir); | |
1da177e4 LT |
327 | } |
328 | } | |
329 | return err; | |
330 | } | |
331 | ||
332 | static int ext2_rename (struct inode * old_dir, struct dentry * old_dentry, | |
333 | struct inode * new_dir, struct dentry * new_dentry ) | |
334 | { | |
2b0143b5 DH |
335 | struct inode * old_inode = d_inode(old_dentry); |
336 | struct inode * new_inode = d_inode(new_dentry); | |
1da177e4 LT |
337 | struct page * dir_page = NULL; |
338 | struct ext2_dir_entry_2 * dir_de = NULL; | |
339 | struct page * old_page; | |
340 | struct ext2_dir_entry_2 * old_de; | |
c2edb305 | 341 | int err; |
1da177e4 | 342 | |
c2edb305 JK |
343 | err = dquot_initialize(old_dir); |
344 | if (err) | |
345 | goto out; | |
346 | ||
347 | err = dquot_initialize(new_dir); | |
348 | if (err) | |
349 | goto out; | |
907f4554 | 350 | |
a9885444 | 351 | old_de = ext2_find_entry (old_dir, &old_dentry->d_name, &old_page); |
c2edb305 JK |
352 | if (!old_de) { |
353 | err = -ENOENT; | |
1da177e4 | 354 | goto out; |
c2edb305 | 355 | } |
1da177e4 LT |
356 | |
357 | if (S_ISDIR(old_inode->i_mode)) { | |
358 | err = -EIO; | |
359 | dir_de = ext2_dotdot(old_inode, &dir_page); | |
360 | if (!dir_de) | |
361 | goto out_old; | |
362 | } | |
363 | ||
364 | if (new_inode) { | |
365 | struct page *new_page; | |
366 | struct ext2_dir_entry_2 *new_de; | |
367 | ||
368 | err = -ENOTEMPTY; | |
369 | if (dir_de && !ext2_empty_dir (new_inode)) | |
370 | goto out_dir; | |
371 | ||
372 | err = -ENOENT; | |
a9885444 | 373 | new_de = ext2_find_entry (new_dir, &new_dentry->d_name, &new_page); |
1da177e4 LT |
374 | if (!new_de) |
375 | goto out_dir; | |
39fe7557 | 376 | ext2_set_link(new_dir, new_de, new_page, old_inode, 1); |
1da177e4 LT |
377 | new_inode->i_ctime = CURRENT_TIME_SEC; |
378 | if (dir_de) | |
9a53c3a7 | 379 | drop_nlink(new_inode); |
a513b035 | 380 | inode_dec_link_count(new_inode); |
1da177e4 | 381 | } else { |
1da177e4 | 382 | err = ext2_add_link(new_dentry, old_inode); |
e8a80c6f | 383 | if (err) |
1da177e4 | 384 | goto out_dir; |
1da177e4 | 385 | if (dir_de) |
a513b035 | 386 | inode_inc_link_count(new_dir); |
1da177e4 LT |
387 | } |
388 | ||
389 | /* | |
390 | * Like most other Unix systems, set the ctime for inodes on a | |
391 | * rename. | |
1da177e4 LT |
392 | */ |
393 | old_inode->i_ctime = CURRENT_TIME_SEC; | |
e8a80c6f | 394 | mark_inode_dirty(old_inode); |
1da177e4 LT |
395 | |
396 | ext2_delete_entry (old_de, old_page); | |
1da177e4 LT |
397 | |
398 | if (dir_de) { | |
39fe7557 JK |
399 | if (old_dir != new_dir) |
400 | ext2_set_link(old_inode, dir_de, dir_page, new_dir, 0); | |
9de6886e NP |
401 | else { |
402 | kunmap(dir_page); | |
403 | page_cache_release(dir_page); | |
404 | } | |
a513b035 | 405 | inode_dec_link_count(old_dir); |
1da177e4 LT |
406 | } |
407 | return 0; | |
408 | ||
409 | ||
410 | out_dir: | |
411 | if (dir_de) { | |
412 | kunmap(dir_page); | |
413 | page_cache_release(dir_page); | |
414 | } | |
415 | out_old: | |
416 | kunmap(old_page); | |
417 | page_cache_release(old_page); | |
418 | out: | |
419 | return err; | |
420 | } | |
421 | ||
754661f1 | 422 | const struct inode_operations ext2_dir_inode_operations = { |
1da177e4 LT |
423 | .create = ext2_create, |
424 | .lookup = ext2_lookup, | |
425 | .link = ext2_link, | |
426 | .unlink = ext2_unlink, | |
427 | .symlink = ext2_symlink, | |
428 | .mkdir = ext2_mkdir, | |
429 | .rmdir = ext2_rmdir, | |
430 | .mknod = ext2_mknod, | |
431 | .rename = ext2_rename, | |
432 | #ifdef CONFIG_EXT2_FS_XATTR | |
433 | .setxattr = generic_setxattr, | |
434 | .getxattr = generic_getxattr, | |
435 | .listxattr = ext2_listxattr, | |
436 | .removexattr = generic_removexattr, | |
437 | #endif | |
438 | .setattr = ext2_setattr, | |
4e34e719 | 439 | .get_acl = ext2_get_acl, |
64e178a7 | 440 | .set_acl = ext2_set_acl, |
60545d0d | 441 | .tmpfile = ext2_tmpfile, |
1da177e4 LT |
442 | }; |
443 | ||
754661f1 | 444 | const struct inode_operations ext2_special_inode_operations = { |
1da177e4 LT |
445 | #ifdef CONFIG_EXT2_FS_XATTR |
446 | .setxattr = generic_setxattr, | |
447 | .getxattr = generic_getxattr, | |
448 | .listxattr = ext2_listxattr, | |
449 | .removexattr = generic_removexattr, | |
450 | #endif | |
451 | .setattr = ext2_setattr, | |
4e34e719 | 452 | .get_acl = ext2_get_acl, |
64e178a7 | 453 | .set_acl = ext2_set_acl, |
1da177e4 | 454 | }; |