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); |
2b0143b5 | 82 | unsigned long ino = ext2_inode_by_name(d_inode(child), &dotdot); |
1da177e4 LT |
83 | if (!ino) |
84 | return ERR_PTR(-ENOENT); | |
fc64005c | 85 | return d_obtain_alias(ext2_iget(child->d_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 | ||
c2edb305 JK |
146 | err = dquot_initialize(dir); |
147 | if (err) | |
148 | return err; | |
907f4554 | 149 | |
2a7dba39 | 150 | inode = ext2_new_inode (dir, mode, &dentry->d_name); |
1da177e4 LT |
151 | err = PTR_ERR(inode); |
152 | if (!IS_ERR(inode)) { | |
153 | init_special_inode(inode, inode->i_mode, rdev); | |
154 | #ifdef CONFIG_EXT2_FS_XATTR | |
155 | inode->i_op = &ext2_special_inode_operations; | |
156 | #endif | |
157 | mark_inode_dirty(inode); | |
158 | err = ext2_add_nondir(dentry, inode); | |
159 | } | |
160 | return err; | |
161 | } | |
162 | ||
163 | static int ext2_symlink (struct inode * dir, struct dentry * dentry, | |
164 | const char * symname) | |
165 | { | |
166 | struct super_block * sb = dir->i_sb; | |
167 | int err = -ENAMETOOLONG; | |
168 | unsigned l = strlen(symname)+1; | |
169 | struct inode * inode; | |
170 | ||
171 | if (l > sb->s_blocksize) | |
172 | goto out; | |
173 | ||
c2edb305 JK |
174 | err = dquot_initialize(dir); |
175 | if (err) | |
176 | goto out; | |
907f4554 | 177 | |
2a7dba39 | 178 | inode = ext2_new_inode (dir, S_IFLNK | S_IRWXUGO, &dentry->d_name); |
1da177e4 LT |
179 | err = PTR_ERR(inode); |
180 | if (IS_ERR(inode)) | |
181 | goto out; | |
182 | ||
183 | if (l > sizeof (EXT2_I(inode)->i_data)) { | |
184 | /* slow symlink */ | |
185 | inode->i_op = &ext2_symlink_inode_operations; | |
21fc61c7 | 186 | inode_nohighmem(inode); |
1da177e4 LT |
187 | if (test_opt(inode->i_sb, NOBH)) |
188 | inode->i_mapping->a_ops = &ext2_nobh_aops; | |
189 | else | |
190 | inode->i_mapping->a_ops = &ext2_aops; | |
191 | err = page_symlink(inode, symname, l); | |
192 | if (err) | |
193 | goto out_fail; | |
194 | } else { | |
195 | /* fast symlink */ | |
196 | inode->i_op = &ext2_fast_symlink_inode_operations; | |
cbe0fa38 AV |
197 | inode->i_link = (char*)EXT2_I(inode)->i_data; |
198 | memcpy(inode->i_link, symname, l); | |
1da177e4 LT |
199 | inode->i_size = l-1; |
200 | } | |
201 | mark_inode_dirty(inode); | |
202 | ||
203 | err = ext2_add_nondir(dentry, inode); | |
204 | out: | |
205 | return err; | |
206 | ||
207 | out_fail: | |
a513b035 | 208 | inode_dec_link_count(inode); |
41080b5a | 209 | unlock_new_inode(inode); |
1da177e4 LT |
210 | iput (inode); |
211 | goto out; | |
212 | } | |
213 | ||
214 | static int ext2_link (struct dentry * old_dentry, struct inode * dir, | |
215 | struct dentry *dentry) | |
216 | { | |
2b0143b5 | 217 | struct inode *inode = d_inode(old_dentry); |
41080b5a | 218 | int err; |
1da177e4 | 219 | |
c2edb305 JK |
220 | err = dquot_initialize(dir); |
221 | if (err) | |
222 | return err; | |
907f4554 | 223 | |
02027d42 | 224 | inode->i_ctime = current_time(inode); |
a513b035 | 225 | inode_inc_link_count(inode); |
7de9c6ee | 226 | ihold(inode); |
1da177e4 | 227 | |
41080b5a AV |
228 | err = ext2_add_link(dentry, inode); |
229 | if (!err) { | |
230 | d_instantiate(dentry, inode); | |
231 | return 0; | |
232 | } | |
233 | inode_dec_link_count(inode); | |
234 | iput(inode); | |
235 | return err; | |
1da177e4 LT |
236 | } |
237 | ||
18bb1db3 | 238 | static int ext2_mkdir(struct inode * dir, struct dentry * dentry, umode_t mode) |
1da177e4 LT |
239 | { |
240 | struct inode * inode; | |
8de52778 | 241 | int err; |
1da177e4 | 242 | |
c2edb305 JK |
243 | err = dquot_initialize(dir); |
244 | if (err) | |
245 | return err; | |
907f4554 | 246 | |
a513b035 | 247 | inode_inc_link_count(dir); |
1da177e4 | 248 | |
2a7dba39 | 249 | inode = ext2_new_inode(dir, S_IFDIR | mode, &dentry->d_name); |
1da177e4 LT |
250 | err = PTR_ERR(inode); |
251 | if (IS_ERR(inode)) | |
252 | goto out_dir; | |
253 | ||
254 | inode->i_op = &ext2_dir_inode_operations; | |
255 | inode->i_fop = &ext2_dir_operations; | |
256 | if (test_opt(inode->i_sb, NOBH)) | |
257 | inode->i_mapping->a_ops = &ext2_nobh_aops; | |
258 | else | |
259 | inode->i_mapping->a_ops = &ext2_aops; | |
260 | ||
a513b035 | 261 | inode_inc_link_count(inode); |
1da177e4 LT |
262 | |
263 | err = ext2_make_empty(inode, dir); | |
264 | if (err) | |
265 | goto out_fail; | |
266 | ||
267 | err = ext2_add_link(dentry, inode); | |
268 | if (err) | |
269 | goto out_fail; | |
270 | ||
41080b5a | 271 | unlock_new_inode(inode); |
8fc37ec5 | 272 | d_instantiate(dentry, inode); |
1da177e4 LT |
273 | out: |
274 | return err; | |
275 | ||
276 | out_fail: | |
a513b035 AD |
277 | inode_dec_link_count(inode); |
278 | inode_dec_link_count(inode); | |
41080b5a | 279 | unlock_new_inode(inode); |
1da177e4 LT |
280 | iput(inode); |
281 | out_dir: | |
a513b035 | 282 | inode_dec_link_count(dir); |
1da177e4 LT |
283 | goto out; |
284 | } | |
285 | ||
286 | static int ext2_unlink(struct inode * dir, struct dentry *dentry) | |
287 | { | |
2b0143b5 | 288 | struct inode * inode = d_inode(dentry); |
1da177e4 LT |
289 | struct ext2_dir_entry_2 * de; |
290 | struct page * page; | |
c2edb305 | 291 | int err; |
1da177e4 | 292 | |
c2edb305 JK |
293 | err = dquot_initialize(dir); |
294 | if (err) | |
295 | goto out; | |
907f4554 | 296 | |
a9885444 | 297 | de = ext2_find_entry (dir, &dentry->d_name, &page); |
c2edb305 JK |
298 | if (!de) { |
299 | err = -ENOENT; | |
1da177e4 | 300 | goto out; |
c2edb305 | 301 | } |
1da177e4 LT |
302 | |
303 | err = ext2_delete_entry (de, page); | |
304 | if (err) | |
305 | goto out; | |
306 | ||
307 | inode->i_ctime = dir->i_ctime; | |
a513b035 | 308 | inode_dec_link_count(inode); |
1da177e4 LT |
309 | err = 0; |
310 | out: | |
311 | return err; | |
312 | } | |
313 | ||
314 | static int ext2_rmdir (struct inode * dir, struct dentry *dentry) | |
315 | { | |
2b0143b5 | 316 | struct inode * inode = d_inode(dentry); |
1da177e4 LT |
317 | int err = -ENOTEMPTY; |
318 | ||
319 | if (ext2_empty_dir(inode)) { | |
320 | err = ext2_unlink(dir, dentry); | |
321 | if (!err) { | |
322 | inode->i_size = 0; | |
a513b035 AD |
323 | inode_dec_link_count(inode); |
324 | inode_dec_link_count(dir); | |
1da177e4 LT |
325 | } |
326 | } | |
327 | return err; | |
328 | } | |
329 | ||
330 | static int ext2_rename (struct inode * old_dir, struct dentry * old_dentry, | |
f03b8ad8 MS |
331 | struct inode * new_dir, struct dentry * new_dentry, |
332 | unsigned int flags) | |
1da177e4 | 333 | { |
2b0143b5 DH |
334 | struct inode * old_inode = d_inode(old_dentry); |
335 | struct inode * new_inode = d_inode(new_dentry); | |
1da177e4 LT |
336 | struct page * dir_page = NULL; |
337 | struct ext2_dir_entry_2 * dir_de = NULL; | |
338 | struct page * old_page; | |
339 | struct ext2_dir_entry_2 * old_de; | |
c2edb305 | 340 | int err; |
1da177e4 | 341 | |
f03b8ad8 MS |
342 | if (flags & ~RENAME_NOREPLACE) |
343 | return -EINVAL; | |
344 | ||
c2edb305 JK |
345 | err = dquot_initialize(old_dir); |
346 | if (err) | |
347 | goto out; | |
348 | ||
349 | err = dquot_initialize(new_dir); | |
350 | if (err) | |
351 | goto out; | |
907f4554 | 352 | |
a9885444 | 353 | old_de = ext2_find_entry (old_dir, &old_dentry->d_name, &old_page); |
c2edb305 JK |
354 | if (!old_de) { |
355 | err = -ENOENT; | |
1da177e4 | 356 | goto out; |
c2edb305 | 357 | } |
1da177e4 LT |
358 | |
359 | if (S_ISDIR(old_inode->i_mode)) { | |
360 | err = -EIO; | |
361 | dir_de = ext2_dotdot(old_inode, &dir_page); | |
362 | if (!dir_de) | |
363 | goto out_old; | |
364 | } | |
365 | ||
366 | if (new_inode) { | |
367 | struct page *new_page; | |
368 | struct ext2_dir_entry_2 *new_de; | |
369 | ||
370 | err = -ENOTEMPTY; | |
371 | if (dir_de && !ext2_empty_dir (new_inode)) | |
372 | goto out_dir; | |
373 | ||
374 | err = -ENOENT; | |
a9885444 | 375 | new_de = ext2_find_entry (new_dir, &new_dentry->d_name, &new_page); |
1da177e4 LT |
376 | if (!new_de) |
377 | goto out_dir; | |
39fe7557 | 378 | ext2_set_link(new_dir, new_de, new_page, old_inode, 1); |
02027d42 | 379 | new_inode->i_ctime = current_time(new_inode); |
1da177e4 | 380 | if (dir_de) |
9a53c3a7 | 381 | drop_nlink(new_inode); |
a513b035 | 382 | inode_dec_link_count(new_inode); |
1da177e4 | 383 | } else { |
1da177e4 | 384 | err = ext2_add_link(new_dentry, old_inode); |
e8a80c6f | 385 | if (err) |
1da177e4 | 386 | goto out_dir; |
1da177e4 | 387 | if (dir_de) |
a513b035 | 388 | inode_inc_link_count(new_dir); |
1da177e4 LT |
389 | } |
390 | ||
391 | /* | |
392 | * Like most other Unix systems, set the ctime for inodes on a | |
393 | * rename. | |
1da177e4 | 394 | */ |
02027d42 | 395 | old_inode->i_ctime = current_time(old_inode); |
e8a80c6f | 396 | mark_inode_dirty(old_inode); |
1da177e4 LT |
397 | |
398 | ext2_delete_entry (old_de, old_page); | |
1da177e4 LT |
399 | |
400 | if (dir_de) { | |
39fe7557 JK |
401 | if (old_dir != new_dir) |
402 | ext2_set_link(old_inode, dir_de, dir_page, new_dir, 0); | |
9de6886e NP |
403 | else { |
404 | kunmap(dir_page); | |
09cbfeaf | 405 | put_page(dir_page); |
9de6886e | 406 | } |
a513b035 | 407 | inode_dec_link_count(old_dir); |
1da177e4 LT |
408 | } |
409 | return 0; | |
410 | ||
411 | ||
412 | out_dir: | |
413 | if (dir_de) { | |
414 | kunmap(dir_page); | |
09cbfeaf | 415 | put_page(dir_page); |
1da177e4 LT |
416 | } |
417 | out_old: | |
418 | kunmap(old_page); | |
09cbfeaf | 419 | put_page(old_page); |
1da177e4 LT |
420 | out: |
421 | return err; | |
422 | } | |
423 | ||
754661f1 | 424 | const struct inode_operations ext2_dir_inode_operations = { |
1da177e4 LT |
425 | .create = ext2_create, |
426 | .lookup = ext2_lookup, | |
427 | .link = ext2_link, | |
428 | .unlink = ext2_unlink, | |
429 | .symlink = ext2_symlink, | |
430 | .mkdir = ext2_mkdir, | |
431 | .rmdir = ext2_rmdir, | |
432 | .mknod = ext2_mknod, | |
433 | .rename = ext2_rename, | |
434 | #ifdef CONFIG_EXT2_FS_XATTR | |
1da177e4 | 435 | .listxattr = ext2_listxattr, |
1da177e4 LT |
436 | #endif |
437 | .setattr = ext2_setattr, | |
4e34e719 | 438 | .get_acl = ext2_get_acl, |
64e178a7 | 439 | .set_acl = ext2_set_acl, |
60545d0d | 440 | .tmpfile = ext2_tmpfile, |
1da177e4 LT |
441 | }; |
442 | ||
754661f1 | 443 | const struct inode_operations ext2_special_inode_operations = { |
1da177e4 | 444 | #ifdef CONFIG_EXT2_FS_XATTR |
1da177e4 | 445 | .listxattr = ext2_listxattr, |
1da177e4 LT |
446 | #endif |
447 | .setattr = ext2_setattr, | |
4e34e719 | 448 | .get_acl = ext2_get_acl, |
64e178a7 | 449 | .set_acl = ext2_set_acl, |
1da177e4 | 450 | }; |