?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
sched: clean up wakeup balancing, move wake_affine()
[wrt350n-kernel.git] / fs / reiserfs / xattr_acl.c
blobb7e4fa4539deeb9155e97affef199cbacb729f70
1 #include <linux/capability.h>
2 #include <linux/fs.h>
3 #include <linux/posix_acl.h>
4 #include <linux/reiserfs_fs.h>
5 #include <linux/errno.h>
6 #include <linux/pagemap.h>
7 #include <linux/xattr.h>
8 #include <linux/posix_acl_xattr.h>
9 #include <linux/reiserfs_xattr.h>
10 #include <linux/reiserfs_acl.h>
11 #include <asm/uaccess.h>
12
13 static int reiserfs_set_acl(struct inode *inode, int type,
14 struct posix_acl *acl);
15
16 static int
17 xattr_set_acl(struct inode *inode, int type, const void *value, size_t size)
18 {
19 struct posix_acl *acl;
20 int error;
21
22 if (!reiserfs_posixacl(inode->i_sb))
23 return -EOPNOTSUPP;
24 if (!is_owner_or_cap(inode))
25 return -EPERM;
26
27 if (value) {
28 acl = posix_acl_from_xattr(value, size);
29 if (IS_ERR(acl)) {
30 return PTR_ERR(acl);
31 } else if (acl) {
32 error = posix_acl_valid(acl);
33 if (error)
34 goto release_and_out;
35 }
36 } else
37 acl = NULL;
38
39 error = reiserfs_set_acl(inode, type, acl);
40
41 release_and_out:
42 posix_acl_release(acl);
43 return error;
44 }
45
46 static int
47 xattr_get_acl(struct inode *inode, int type, void *buffer, size_t size)
48 {
49 struct posix_acl *acl;
50 int error;
51
52 if (!reiserfs_posixacl(inode->i_sb))
53 return -EOPNOTSUPP;
54
55 acl = reiserfs_get_acl(inode, type);
56 if (IS_ERR(acl))
57 return PTR_ERR(acl);
58 if (acl == NULL)
59 return -ENODATA;
60 error = posix_acl_to_xattr(acl, buffer, size);
61 posix_acl_release(acl);
62
63 return error;
64 }
65
66 /*
67 * Convert from filesystem to in-memory representation.
68 */
69 static struct posix_acl *posix_acl_from_disk(const void *value, size_t size)
70 {
71 const char *end = (char *)value + size;
72 int n, count;
73 struct posix_acl *acl;
74
75 if (!value)
76 return NULL;
77 if (size < sizeof(reiserfs_acl_header))
78 return ERR_PTR(-EINVAL);
79 if (((reiserfs_acl_header *) value)->a_version !=
80 cpu_to_le32(REISERFS_ACL_VERSION))
81 return ERR_PTR(-EINVAL);
82 value = (char *)value + sizeof(reiserfs_acl_header);
83 count = reiserfs_acl_count(size);
84 if (count < 0)
85 return ERR_PTR(-EINVAL);
86 if (count == 0)
87 return NULL;
88 acl = posix_acl_alloc(count, GFP_NOFS);
89 if (!acl)
90 return ERR_PTR(-ENOMEM);
91 for (n = 0; n < count; n++) {
92 reiserfs_acl_entry *entry = (reiserfs_acl_entry *) value;
93 if ((char *)value + sizeof(reiserfs_acl_entry_short) > end)
94 goto fail;
95 acl->a_entries[n].e_tag = le16_to_cpu(entry->e_tag);
96 acl->a_entries[n].e_perm = le16_to_cpu(entry->e_perm);
97 switch (acl->a_entries[n].e_tag) {
98 case ACL_USER_OBJ:
99 case ACL_GROUP_OBJ:
100 case ACL_MASK:
101 case ACL_OTHER:
102 value = (char *)value +
103 sizeof(reiserfs_acl_entry_short);
104 acl->a_entries[n].e_id = ACL_UNDEFINED_ID;
105 break;
106
107 case ACL_USER:
108 case ACL_GROUP:
109 value = (char *)value + sizeof(reiserfs_acl_entry);
110 if ((char *)value > end)
111 goto fail;
112 acl->a_entries[n].e_id = le32_to_cpu(entry->e_id);
113 break;
114
115 default:
116 goto fail;
117 }
118 }
119 if (value != end)
120 goto fail;
121 return acl;
122
123 fail:
124 posix_acl_release(acl);
125 return ERR_PTR(-EINVAL);
126 }
127
128 /*
129 * Convert from in-memory to filesystem representation.
130 */
131 static void *posix_acl_to_disk(const struct posix_acl *acl, size_t * size)
132 {
133 reiserfs_acl_header *ext_acl;
134 char *e;
135 int n;
136
137 *size = reiserfs_acl_size(acl->a_count);
138 ext_acl = kmalloc(sizeof(reiserfs_acl_header) +
139 acl->a_count *
140 sizeof(reiserfs_acl_entry),
141 GFP_NOFS);
142 if (!ext_acl)
143 return ERR_PTR(-ENOMEM);
144 ext_acl->a_version = cpu_to_le32(REISERFS_ACL_VERSION);
145 e = (char *)ext_acl + sizeof(reiserfs_acl_header);
146 for (n = 0; n < acl->a_count; n++) {
147 reiserfs_acl_entry *entry = (reiserfs_acl_entry *) e;
148 entry->e_tag = cpu_to_le16(acl->a_entries[n].e_tag);
149 entry->e_perm = cpu_to_le16(acl->a_entries[n].e_perm);
150 switch (acl->a_entries[n].e_tag) {
151 case ACL_USER:
152 case ACL_GROUP:
153 entry->e_id = cpu_to_le32(acl->a_entries[n].e_id);
154 e += sizeof(reiserfs_acl_entry);
155 break;
156
157 case ACL_USER_OBJ:
158 case ACL_GROUP_OBJ:
159 case ACL_MASK:
160 case ACL_OTHER:
161 e += sizeof(reiserfs_acl_entry_short);
162 break;
163
164 default:
165 goto fail;
166 }
167 }
168 return (char *)ext_acl;
169
170 fail:
171 kfree(ext_acl);
172 return ERR_PTR(-EINVAL);
173 }
174
175 /*
176 * Inode operation get_posix_acl().
177 *
178 * inode->i_mutex: down
179 * BKL held [before 2.5.x]
180 */
181 struct posix_acl *reiserfs_get_acl(struct inode *inode, int type)
182 {
183 char *name, *value;
184 struct posix_acl *acl, **p_acl;
185 int size;
186 int retval;
187 struct reiserfs_inode_info *reiserfs_i = REISERFS_I(inode);
188
189 switch (type) {
190 case ACL_TYPE_ACCESS:
191 name = POSIX_ACL_XATTR_ACCESS;
192 p_acl = &reiserfs_i->i_acl_access;
193 break;
194 case ACL_TYPE_DEFAULT:
195 name = POSIX_ACL_XATTR_DEFAULT;
196 p_acl = &reiserfs_i->i_acl_default;
197 break;
198 default:
199 return ERR_PTR(-EINVAL);
200 }
201
202 if (IS_ERR(*p_acl)) {
203 if (PTR_ERR(*p_acl) == -ENODATA)
204 return NULL;
205 } else if (*p_acl != NULL)
206 return posix_acl_dup(*p_acl);
207
208 size = reiserfs_xattr_get(inode, name, NULL, 0);
209 if (size < 0) {
210 if (size == -ENODATA || size == -ENOSYS) {
211 *p_acl = ERR_PTR(-ENODATA);
212 return NULL;
213 }
214 return ERR_PTR(size);
215 }
216
217 value = kmalloc(size, GFP_NOFS);
218 if (!value)
219 return ERR_PTR(-ENOMEM);
220
221 retval = reiserfs_xattr_get(inode, name, value, size);
222 if (retval == -ENODATA || retval == -ENOSYS) {
223 /* This shouldn't actually happen as it should have
224 been caught above.. but just in case */
225 acl = NULL;
226 *p_acl = ERR_PTR(-ENODATA);
227 } else if (retval < 0) {
228 acl = ERR_PTR(retval);
229 } else {
230 acl = posix_acl_from_disk(value, retval);
231 if (!IS_ERR(acl))
232 *p_acl = posix_acl_dup(acl);
233 }
234
235 kfree(value);
236 return acl;
237 }
238
239 /*
240 * Inode operation set_posix_acl().
241 *
242 * inode->i_mutex: down
243 * BKL held [before 2.5.x]
244 */
245 static int
246 reiserfs_set_acl(struct inode *inode, int type, struct posix_acl *acl)
247 {
248 char *name;
249 void *value = NULL;
250 struct posix_acl **p_acl;
251 size_t size;
252 int error;
253 struct reiserfs_inode_info *reiserfs_i = REISERFS_I(inode);
254
255 if (S_ISLNK(inode->i_mode))
256 return -EOPNOTSUPP;
257
258 switch (type) {
259 case ACL_TYPE_ACCESS:
260 name = POSIX_ACL_XATTR_ACCESS;
261 p_acl = &reiserfs_i->i_acl_access;
262 if (acl) {
263 mode_t mode = inode->i_mode;
264 error = posix_acl_equiv_mode(acl, &mode);
265 if (error < 0)
266 return error;
267 else {
268 inode->i_mode = mode;
269 if (error == 0)
270 acl = NULL;
271 }
272 }
273 break;
274 case ACL_TYPE_DEFAULT:
275 name = POSIX_ACL_XATTR_DEFAULT;
276 p_acl = &reiserfs_i->i_acl_default;
277 if (!S_ISDIR(inode->i_mode))
278 return acl ? -EACCES : 0;
279 break;
280 default:
281 return -EINVAL;
282 }
283
284 if (acl) {
285 value = posix_acl_to_disk(acl, &size);
286 if (IS_ERR(value))
287 return (int)PTR_ERR(value);
288 error = reiserfs_xattr_set(inode, name, value, size, 0);
289 } else {
290 error = reiserfs_xattr_del(inode, name);
291 if (error == -ENODATA) {
292 /* This may seem odd here, but it means that the ACL was set
293 * with a value representable with mode bits. If there was
294 * an ACL before, reiserfs_xattr_del already dirtied the inode.
295 */
296 mark_inode_dirty(inode);
297 error = 0;
298 }
299 }
300
301 kfree(value);
302
303 if (!error) {
304 /* Release the old one */
305 if (!IS_ERR(*p_acl) && *p_acl)
306 posix_acl_release(*p_acl);
307
308 if (acl == NULL)
309 *p_acl = ERR_PTR(-ENODATA);
310 else
311 *p_acl = posix_acl_dup(acl);
312 }
313
314 return error;
315 }
316
317 /* dir->i_mutex: locked,
318 * inode is new and not released into the wild yet */
319 int
320 reiserfs_inherit_default_acl(struct inode *dir, struct dentry *dentry,
321 struct inode *inode)
322 {
323 struct posix_acl *acl;
324 int err = 0;
325
326 /* ACLs only get applied to files and directories */
327 if (S_ISLNK(inode->i_mode))
328 return 0;
329
330 /* ACLs can only be used on "new" objects, so if it's an old object
331 * there is nothing to inherit from */
332 if (get_inode_sd_version(dir) == STAT_DATA_V1)
333 goto apply_umask;
334
335 /* Don't apply ACLs to objects in the .reiserfs_priv tree.. This
336 * would be useless since permissions are ignored, and a pain because
337 * it introduces locking cycles */
338 if (is_reiserfs_priv_object(dir)) {
339 reiserfs_mark_inode_private(inode);
340 goto apply_umask;
341 }
342
343 acl = reiserfs_get_acl(dir, ACL_TYPE_DEFAULT);
344 if (IS_ERR(acl)) {
345 if (PTR_ERR(acl) == -ENODATA)
346 goto apply_umask;
347 return PTR_ERR(acl);
348 }
349
350 if (acl) {
351 struct posix_acl *acl_copy;
352 mode_t mode = inode->i_mode;
353 int need_acl;
354
355 /* Copy the default ACL to the default ACL of a new directory */
356 if (S_ISDIR(inode->i_mode)) {
357 err = reiserfs_set_acl(inode, ACL_TYPE_DEFAULT, acl);
358 if (err)
359 goto cleanup;
360 }
361
362 /* Now we reconcile the new ACL and the mode,
363 potentially modifying both */
364 acl_copy = posix_acl_clone(acl, GFP_NOFS);
365 if (!acl_copy) {
366 err = -ENOMEM;
367 goto cleanup;
368 }
369
370 need_acl = posix_acl_create_masq(acl_copy, &mode);
371 if (need_acl >= 0) {
372 if (mode != inode->i_mode) {
373 inode->i_mode = mode;
374 }
375
376 /* If we need an ACL.. */
377 if (need_acl > 0) {
378 err =
379 reiserfs_set_acl(inode, ACL_TYPE_ACCESS,
380 acl_copy);
381 if (err)
382 goto cleanup_copy;
383 }
384 }
385 cleanup_copy:
386 posix_acl_release(acl_copy);
387 cleanup:
388 posix_acl_release(acl);
389 } else {
390 apply_umask:
391 /* no ACL, apply umask */
392 inode->i_mode &= ~current->fs->umask;
393 }
394
395 return err;
396 }
397
398 /* Looks up and caches the result of the default ACL.
399 * We do this so that we don't need to carry the xattr_sem into
400 * reiserfs_new_inode if we don't need to */
401 int reiserfs_cache_default_acl(struct inode *inode)
402 {
403 int ret = 0;
404 if (reiserfs_posixacl(inode->i_sb) && !is_reiserfs_priv_object(inode)) {
405 struct posix_acl *acl;
406 reiserfs_read_lock_xattr_i(inode);
407 reiserfs_read_lock_xattrs(inode->i_sb);
408 acl = reiserfs_get_acl(inode, ACL_TYPE_DEFAULT);
409 reiserfs_read_unlock_xattrs(inode->i_sb);
410 reiserfs_read_unlock_xattr_i(inode);
411 ret = (acl && !IS_ERR(acl));
412 if (ret)
413 posix_acl_release(acl);
414 }
415
416 return ret;
417 }
418
419 int reiserfs_acl_chmod(struct inode *inode)
420 {
421 struct posix_acl *acl, *clone;
422 int error;
423
424 if (S_ISLNK(inode->i_mode))
425 return -EOPNOTSUPP;
426
427 if (get_inode_sd_version(inode) == STAT_DATA_V1 ||
428 !reiserfs_posixacl(inode->i_sb)) {
429 return 0;
430 }
431
432 reiserfs_read_lock_xattrs(inode->i_sb);
433 acl = reiserfs_get_acl(inode, ACL_TYPE_ACCESS);
434 reiserfs_read_unlock_xattrs(inode->i_sb);
435 if (!acl)
436 return 0;
437 if (IS_ERR(acl))
438 return PTR_ERR(acl);
439 clone = posix_acl_clone(acl, GFP_NOFS);
440 posix_acl_release(acl);
441 if (!clone)
442 return -ENOMEM;
443 error = posix_acl_chmod_masq(clone, inode->i_mode);
444 if (!error) {
445 int lock = !has_xattr_dir(inode);
446 reiserfs_write_lock_xattr_i(inode);
447 if (lock)
448 reiserfs_write_lock_xattrs(inode->i_sb);
449 else
450 reiserfs_read_lock_xattrs(inode->i_sb);
451 error = reiserfs_set_acl(inode, ACL_TYPE_ACCESS, clone);
452 if (lock)
453 reiserfs_write_unlock_xattrs(inode->i_sb);
454 else
455 reiserfs_read_unlock_xattrs(inode->i_sb);
456 reiserfs_write_unlock_xattr_i(inode);
457 }
458 posix_acl_release(clone);
459 return error;
460 }
461
462 static int
463 posix_acl_access_get(struct inode *inode, const char *name,
464 void *buffer, size_t size)
465 {
466 if (strlen(name) != sizeof(POSIX_ACL_XATTR_ACCESS) - 1)
467 return -EINVAL;
468 return xattr_get_acl(inode, ACL_TYPE_ACCESS, buffer, size);
469 }
470
471 static int
472 posix_acl_access_set(struct inode *inode, const char *name,
473 const void *value, size_t size, int flags)
474 {
475 if (strlen(name) != sizeof(POSIX_ACL_XATTR_ACCESS) - 1)
476 return -EINVAL;
477 return xattr_set_acl(inode, ACL_TYPE_ACCESS, value, size);
478 }
479
480 static int posix_acl_access_del(struct inode *inode, const char *name)
481 {
482 struct reiserfs_inode_info *reiserfs_i = REISERFS_I(inode);
483 struct posix_acl **acl = &reiserfs_i->i_acl_access;
484 if (strlen(name) != sizeof(POSIX_ACL_XATTR_ACCESS) - 1)
485 return -EINVAL;
486 if (!IS_ERR(*acl) && *acl) {
487 posix_acl_release(*acl);
488 *acl = ERR_PTR(-ENODATA);
489 }
490
491 return 0;
492 }
493
494 static int
495 posix_acl_access_list(struct inode *inode, const char *name, int namelen,
496 char *out)
497 {
498 int len = namelen;
499 if (!reiserfs_posixacl(inode->i_sb))
500 return 0;
501 if (out)
502 memcpy(out, name, len);
503
504 return len;
505 }
506
507 struct reiserfs_xattr_handler posix_acl_access_handler = {
508 .prefix = POSIX_ACL_XATTR_ACCESS,
509 .get = posix_acl_access_get,
510 .set = posix_acl_access_set,
511 .del = posix_acl_access_del,
512 .list = posix_acl_access_list,
513 };
514
515 static int
516 posix_acl_default_get(struct inode *inode, const char *name,
517 void *buffer, size_t size)
518 {
519 if (strlen(name) != sizeof(POSIX_ACL_XATTR_DEFAULT) - 1)
520 return -EINVAL;
521 return xattr_get_acl(inode, ACL_TYPE_DEFAULT, buffer, size);
522 }
523
524 static int
525 posix_acl_default_set(struct inode *inode, const char *name,
526 const void *value, size_t size, int flags)
527 {
528 if (strlen(name) != sizeof(POSIX_ACL_XATTR_DEFAULT) - 1)
529 return -EINVAL;
530 return xattr_set_acl(inode, ACL_TYPE_DEFAULT, value, size);
531 }
532
533 static int posix_acl_default_del(struct inode *inode, const char *name)
534 {
535 struct reiserfs_inode_info *reiserfs_i = REISERFS_I(inode);
536 struct posix_acl **acl = &reiserfs_i->i_acl_default;
537 if (strlen(name) != sizeof(POSIX_ACL_XATTR_DEFAULT) - 1)
538 return -EINVAL;
539 if (!IS_ERR(*acl) && *acl) {
540 posix_acl_release(*acl);
541 *acl = ERR_PTR(-ENODATA);
542 }
543
544 return 0;
545 }
546
547 static int
548 posix_acl_default_list(struct inode *inode, const char *name, int namelen,
549 char *out)
550 {
551 int len = namelen;
552 if (!reiserfs_posixacl(inode->i_sb))
553 return 0;
554 if (out)
555 memcpy(out, name, len);
556
557 return len;
558 }
559
560 struct reiserfs_xattr_handler posix_acl_default_handler = {
561 .prefix = POSIX_ACL_XATTR_DEFAULT,
562 .get = posix_acl_default_get,
563 .set = posix_acl_default_set,
564 .del = posix_acl_default_del,
565 .list = posix_acl_default_list,
566 };
WRT350N Kernel Patches