Commit | Line | Data |
---|---|---|
5103e947 JB |
1 | /* |
2 | * Copyright (C) 2007 Red Hat. All rights reserved. | |
3 | * | |
4 | * This program is free software; you can redistribute it and/or | |
5 | * modify it under the terms of the GNU General Public | |
6 | * License v2 as published by the Free Software Foundation. | |
7 | * | |
8 | * This program is distributed in the hope that it will be useful, | |
9 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
10 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
11 | * General Public License for more details. | |
12 | * | |
13 | * You should have received a copy of the GNU General Public | |
14 | * License along with this program; if not, write to the | |
15 | * Free Software Foundation, Inc., 59 Temple Place - Suite 330, | |
16 | * Boston, MA 021110-1307, USA. | |
17 | */ | |
18 | ||
19 | #include <linux/init.h> | |
20 | #include <linux/fs.h> | |
21 | #include <linux/slab.h> | |
22 | #include <linux/rwsem.h> | |
23 | #include <linux/xattr.h> | |
24 | #include "ctree.h" | |
25 | #include "btrfs_inode.h" | |
26 | #include "transaction.h" | |
27 | #include "xattr.h" | |
28 | #include "disk-io.h" | |
5103e947 JB |
29 | static struct xattr_handler *btrfs_xattr_handler_map[] = { |
30 | [BTRFS_XATTR_INDEX_USER] = &btrfs_xattr_user_handler, | |
caaca38b | 31 | #ifdef CONFIG_FS_POSIX_ACL |
eba12c7b Y |
32 | // [BTRFS_XATTR_INDEX_POSIX_ACL_ACCESS] = &btrfs_xattr_acl_access_handler, |
33 | // [BTRFS_XATTR_INDEX_POSIX_ACL_DEFAULT] = &btrfs_xattr_acl_default_handler, | |
caaca38b | 34 | #endif |
5103e947 JB |
35 | [BTRFS_XATTR_INDEX_TRUSTED] = &btrfs_xattr_trusted_handler, |
36 | [BTRFS_XATTR_INDEX_SECURITY] = &btrfs_xattr_security_handler, | |
eba12c7b | 37 | // [BTRFS_XATTR_INDEX_SYSTEM] = &btrfs_xattr_system_handler, |
5103e947 | 38 | }; |
5103e947 JB |
39 | struct xattr_handler *btrfs_xattr_handlers[] = { |
40 | &btrfs_xattr_user_handler, | |
caaca38b | 41 | #ifdef CONFIG_FS_POSIX_ACL |
eba12c7b Y |
42 | // &btrfs_xattr_acl_access_handler, |
43 | // &btrfs_xattr_acl_default_handler, | |
caaca38b | 44 | #endif |
5103e947 JB |
45 | &btrfs_xattr_trusted_handler, |
46 | &btrfs_xattr_security_handler, | |
eba12c7b | 47 | // &btrfs_xattr_system_handler, |
5103e947 JB |
48 | NULL, |
49 | }; | |
50 | ||
51 | /* | |
52 | * @param name - the xattr name | |
53 | * @return - the xattr_handler for the xattr, NULL if its not found | |
54 | * | |
55 | * use this with listxattr where we don't already know the type of xattr we | |
56 | * have | |
57 | */ | |
58 | static struct xattr_handler *find_btrfs_xattr_handler(struct extent_buffer *l, | |
59 | unsigned long name_ptr, | |
60 | u16 name_len) | |
61 | { | |
62 | struct xattr_handler *handler = NULL; | |
63 | int i = 0; | |
64 | ||
65 | for (handler = btrfs_xattr_handlers[i]; handler != NULL; i++, | |
66 | handler = btrfs_xattr_handlers[i]) { | |
67 | u16 prefix_len = strlen(handler->prefix); | |
68 | ||
69 | if (name_len < prefix_len) | |
70 | continue; | |
71 | ||
72 | if (memcmp_extent_buffer(l, handler->prefix, name_ptr, | |
73 | prefix_len) == 0) | |
74 | break; | |
75 | } | |
76 | ||
77 | return handler; | |
78 | } | |
79 | ||
80 | /* | |
81 | * @param name_index - the index for the xattr handler | |
82 | * @return the xattr_handler if we found it, NULL otherwise | |
83 | * | |
84 | * use this if we know the type of the xattr already | |
85 | */ | |
86 | static struct xattr_handler *btrfs_xattr_handler(int name_index) | |
87 | { | |
88 | struct xattr_handler *handler = NULL; | |
89 | ||
90 | if (name_index >= 0 && | |
91 | name_index < ARRAY_SIZE(btrfs_xattr_handler_map)) | |
92 | handler = btrfs_xattr_handler_map[name_index]; | |
93 | ||
94 | return handler; | |
95 | } | |
96 | ||
97 | static inline char *get_name(const char *name, int name_index) | |
98 | { | |
99 | char *ret = NULL; | |
100 | struct xattr_handler *handler = btrfs_xattr_handler(name_index); | |
101 | int prefix_len; | |
102 | ||
103 | if (!handler) | |
104 | return ret; | |
105 | ||
106 | prefix_len = strlen(handler->prefix); | |
107 | ||
108 | ret = kmalloc(strlen(name) + prefix_len + 1, GFP_KERNEL); | |
109 | if (!ret) | |
110 | return ret; | |
111 | ||
112 | memcpy(ret, handler->prefix, prefix_len); | |
113 | memcpy(ret+prefix_len, name, strlen(name)); | |
114 | ret[prefix_len + strlen(name)] = '\0'; | |
115 | ||
116 | return ret; | |
117 | } | |
118 | ||
119 | size_t btrfs_xattr_generic_list(struct inode *inode, char *list, | |
120 | size_t list_size, const char *name, | |
121 | size_t name_len) | |
122 | { | |
123 | if (list && (name_len+1) <= list_size) { | |
124 | memcpy(list, name, name_len); | |
125 | list[name_len] = '\0'; | |
126 | } else | |
127 | return -ERANGE; | |
128 | ||
129 | return name_len+1; | |
130 | } | |
131 | ||
132 | ssize_t btrfs_xattr_get(struct inode *inode, int name_index, | |
133 | const char *attr_name, void *buffer, size_t size) | |
134 | { | |
135 | struct btrfs_dir_item *di; | |
136 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
137 | struct btrfs_path *path; | |
138 | struct extent_buffer *leaf; | |
139 | struct xattr_handler *handler = btrfs_xattr_handler(name_index); | |
140 | int ret = 0; | |
141 | unsigned long data_ptr; | |
142 | char *name; | |
143 | ||
144 | if (!handler) | |
145 | return -EOPNOTSUPP; | |
5103e947 JB |
146 | name = get_name(attr_name, name_index); |
147 | if (!name) | |
148 | return -ENOMEM; | |
149 | ||
150 | path = btrfs_alloc_path(); | |
151 | if (!path) { | |
152 | kfree(name); | |
153 | return -ENOMEM; | |
154 | } | |
155 | ||
156 | mutex_lock(&root->fs_info->fs_mutex); | |
157 | /* lookup the xattr by name */ | |
158 | di = btrfs_lookup_xattr(NULL, root, path, inode->i_ino, name, | |
159 | strlen(name), 0); | |
160 | if (!di || IS_ERR(di)) { | |
161 | ret = -ENODATA; | |
162 | goto out; | |
163 | } | |
164 | ||
165 | leaf = path->nodes[0]; | |
166 | /* if size is 0, that means we want the size of the attr */ | |
167 | if (!size) { | |
168 | ret = btrfs_dir_data_len(leaf, di); | |
169 | goto out; | |
170 | } | |
171 | ||
172 | /* now get the data out of our dir_item */ | |
173 | if (btrfs_dir_data_len(leaf, di) > size) { | |
174 | ret = -ERANGE; | |
175 | goto out; | |
176 | } | |
177 | data_ptr = (unsigned long)((char *)(di + 1) + | |
178 | btrfs_dir_name_len(leaf, di)); | |
179 | read_extent_buffer(leaf, buffer, data_ptr, | |
3acd7ee8 | 180 | btrfs_dir_data_len(leaf, di)); |
5103e947 JB |
181 | ret = btrfs_dir_data_len(leaf, di); |
182 | ||
183 | out: | |
184 | mutex_unlock(&root->fs_info->fs_mutex); | |
185 | kfree(name); | |
186 | btrfs_free_path(path); | |
187 | return ret; | |
188 | } | |
189 | ||
190 | int btrfs_xattr_set(struct inode *inode, int name_index, | |
191 | const char *attr_name, const void *value, size_t size, | |
192 | int flags) | |
193 | { | |
194 | struct btrfs_dir_item *di; | |
195 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
196 | struct btrfs_trans_handle *trans; | |
197 | struct btrfs_path *path; | |
198 | struct xattr_handler *handler = btrfs_xattr_handler(name_index); | |
199 | char *name; | |
200 | int ret = 0, mod = 0; | |
5103e947 JB |
201 | if (!handler) |
202 | return -EOPNOTSUPP; | |
5103e947 JB |
203 | name = get_name(attr_name, name_index); |
204 | if (!name) | |
205 | return -ENOMEM; | |
206 | ||
207 | path = btrfs_alloc_path(); | |
208 | if (!path) { | |
209 | kfree(name); | |
210 | return -ENOMEM; | |
211 | } | |
212 | ||
213 | mutex_lock(&root->fs_info->fs_mutex); | |
214 | trans = btrfs_start_transaction(root, 1); | |
215 | btrfs_set_trans_block_group(trans, inode); | |
216 | ||
217 | /* first lets see if we already have this xattr */ | |
218 | di = btrfs_lookup_xattr(trans, root, path, inode->i_ino, name, | |
219 | strlen(name), -1); | |
220 | if (IS_ERR(di)) { | |
221 | ret = PTR_ERR(di); | |
222 | goto out; | |
223 | } | |
224 | ||
225 | /* ok we already have this xattr, lets remove it */ | |
226 | if (di) { | |
227 | /* if we want create only exit */ | |
228 | if (flags & XATTR_CREATE) { | |
229 | ret = -EEXIST; | |
230 | goto out; | |
231 | } | |
232 | ||
233 | ret = btrfs_delete_one_dir_name(trans, root, path, di); | |
234 | if (ret) | |
235 | goto out; | |
236 | btrfs_release_path(root, path); | |
237 | ||
238 | /* if we don't have a value then we are removing the xattr */ | |
239 | if (!value) { | |
240 | mod = 1; | |
241 | goto out; | |
242 | } | |
243 | } else if (flags & XATTR_REPLACE) { | |
244 | /* we couldn't find the attr to replace, so error out */ | |
245 | ret = -ENODATA; | |
246 | goto out; | |
247 | } | |
248 | ||
249 | /* ok we have to create a completely new xattr */ | |
250 | ret = btrfs_insert_xattr_item(trans, root, name, strlen(name), | |
251 | value, size, inode->i_ino); | |
252 | if (ret) | |
253 | goto out; | |
254 | mod = 1; | |
255 | ||
256 | out: | |
257 | if (mod) { | |
258 | inode->i_ctime = CURRENT_TIME; | |
259 | ret = btrfs_update_inode(trans, root, inode); | |
260 | } | |
261 | ||
262 | btrfs_end_transaction(trans, root); | |
263 | mutex_unlock(&root->fs_info->fs_mutex); | |
264 | kfree(name); | |
265 | btrfs_free_path(path); | |
266 | ||
267 | return ret; | |
268 | } | |
269 | ||
270 | ssize_t btrfs_listxattr(struct dentry *dentry, char *buffer, size_t size) | |
271 | { | |
272 | struct btrfs_key key, found_key; | |
273 | struct inode *inode = dentry->d_inode; | |
274 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
275 | struct btrfs_path *path; | |
276 | struct btrfs_item *item; | |
277 | struct extent_buffer *leaf; | |
278 | struct btrfs_dir_item *di; | |
279 | struct xattr_handler *handler; | |
280 | int ret = 0, slot, advance; | |
281 | size_t total_size = 0, size_left = size, written; | |
282 | unsigned long name_ptr; | |
283 | char *name; | |
284 | u32 nritems; | |
285 | ||
286 | /* | |
287 | * ok we want all objects associated with this id. | |
288 | * NOTE: we set key.offset = 0; because we want to start with the | |
289 | * first xattr that we find and walk forward | |
290 | */ | |
291 | key.objectid = inode->i_ino; | |
292 | btrfs_set_key_type(&key, BTRFS_XATTR_ITEM_KEY); | |
293 | key.offset = 0; | |
294 | ||
295 | path = btrfs_alloc_path(); | |
5103e947 JB |
296 | if (!path) |
297 | return -ENOMEM; | |
1caf9342 | 298 | path->reada = 2; |
5103e947 JB |
299 | |
300 | mutex_lock(&root->fs_info->fs_mutex); | |
301 | ||
302 | /* search for our xattrs */ | |
303 | ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); | |
304 | if (ret < 0) | |
305 | goto err; | |
306 | ret = 0; | |
307 | advance = 0; | |
308 | while (1) { | |
309 | leaf = path->nodes[0]; | |
310 | nritems = btrfs_header_nritems(leaf); | |
311 | slot = path->slots[0]; | |
312 | ||
313 | /* this is where we start walking through the path */ | |
314 | if (advance || slot >= nritems) { | |
315 | /* | |
316 | * if we've reached the last slot in this leaf we need | |
317 | * to go to the next leaf and reset everything | |
318 | */ | |
319 | if (slot >= nritems-1) { | |
320 | ret = btrfs_next_leaf(root, path); | |
321 | if (ret) | |
322 | break; | |
323 | leaf = path->nodes[0]; | |
324 | nritems = btrfs_header_nritems(leaf); | |
325 | slot = path->slots[0]; | |
326 | } else { | |
327 | /* | |
328 | * just walking through the slots on this leaf | |
329 | */ | |
330 | slot++; | |
331 | path->slots[0]++; | |
332 | } | |
333 | } | |
334 | advance = 1; | |
335 | ||
336 | item = btrfs_item_nr(leaf, slot); | |
337 | btrfs_item_key_to_cpu(leaf, &found_key, slot); | |
338 | ||
339 | /* check to make sure this item is what we want */ | |
340 | if (found_key.objectid != key.objectid) | |
341 | break; | |
342 | if (btrfs_key_type(&found_key) != BTRFS_XATTR_ITEM_KEY) | |
343 | break; | |
344 | ||
345 | di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item); | |
346 | ||
347 | total_size += btrfs_dir_name_len(leaf, di)+1; | |
348 | ||
349 | /* we are just looking for how big our buffer needs to be */ | |
350 | if (!size) | |
351 | continue; | |
352 | ||
353 | /* find our handler for this xattr */ | |
354 | name_ptr = (unsigned long)(di + 1); | |
355 | handler = find_btrfs_xattr_handler(leaf, name_ptr, | |
356 | btrfs_dir_name_len(leaf, di)); | |
357 | if (!handler) { | |
358 | printk(KERN_ERR "btrfs: unsupported xattr found\n"); | |
359 | continue; | |
360 | } | |
361 | ||
362 | name = kmalloc(btrfs_dir_name_len(leaf, di), GFP_KERNEL); | |
363 | read_extent_buffer(leaf, name, name_ptr, | |
364 | btrfs_dir_name_len(leaf, di)); | |
365 | ||
366 | /* call the list function associated with this xattr */ | |
367 | written = handler->list(inode, buffer, size_left, name, | |
368 | btrfs_dir_name_len(leaf, di)); | |
369 | kfree(name); | |
370 | ||
371 | if (written < 0) { | |
372 | ret = -ERANGE; | |
373 | break; | |
374 | } | |
375 | ||
376 | size_left -= written; | |
377 | buffer += written; | |
378 | } | |
379 | ret = total_size; | |
380 | ||
381 | err: | |
382 | mutex_unlock(&root->fs_info->fs_mutex); | |
383 | btrfs_free_path(path); | |
384 | ||
385 | return ret; | |
386 | } | |
387 | ||
388 | /* | |
389 | * delete all the xattrs associated with the inode. fs_mutex should be | |
390 | * held when we come into here | |
391 | */ | |
392 | int btrfs_delete_xattrs(struct btrfs_trans_handle *trans, | |
393 | struct btrfs_root *root, struct inode *inode) | |
394 | { | |
395 | struct btrfs_path *path; | |
396 | struct btrfs_key key, found_key; | |
397 | struct btrfs_item *item; | |
398 | struct extent_buffer *leaf; | |
399 | int ret; | |
400 | ||
401 | path = btrfs_alloc_path(); | |
402 | if (!path) | |
403 | return -ENOMEM; | |
1caf9342 | 404 | path->reada = -1; |
5103e947 JB |
405 | key.objectid = inode->i_ino; |
406 | btrfs_set_key_type(&key, BTRFS_XATTR_ITEM_KEY); | |
407 | key.offset = (u64)-1; | |
408 | ||
409 | while(1) { | |
410 | /* look for our next xattr */ | |
411 | ret = btrfs_search_slot(trans, root, &key, path, -1, 1); | |
412 | if (ret < 0) | |
413 | goto out; | |
414 | BUG_ON(ret == 0); | |
415 | ||
416 | if (path->slots[0] == 0) | |
417 | break; | |
418 | ||
419 | path->slots[0]--; | |
420 | leaf = path->nodes[0]; | |
421 | item = btrfs_item_nr(leaf, path->slots[0]); | |
422 | btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); | |
423 | ||
424 | if (found_key.objectid != key.objectid) | |
425 | break; | |
426 | if (btrfs_key_type(&found_key) != BTRFS_XATTR_ITEM_KEY) | |
427 | break; | |
428 | ||
429 | ret = btrfs_del_item(trans, root, path); | |
430 | BUG_ON(ret); | |
431 | btrfs_release_path(root, path); | |
432 | } | |
433 | ret = 0; | |
434 | out: | |
435 | btrfs_free_path(path); | |
436 | ||
437 | return ret; | |
438 | } | |
439 | ||
440 | /* | |
441 | * Handler functions | |
442 | */ | |
443 | #define BTRFS_XATTR_SETGET_FUNCS(name, index) \ | |
444 | static int btrfs_xattr_##name##_get(struct inode *inode, \ | |
445 | const char *name, void *value, \ | |
446 | size_t size) \ | |
447 | { \ | |
744f52f9 Y |
448 | if (*name == '\0') \ |
449 | return -EINVAL; \ | |
5103e947 JB |
450 | return btrfs_xattr_get(inode, index, name, value, size); \ |
451 | } \ | |
452 | static int btrfs_xattr_##name##_set(struct inode *inode, \ | |
453 | const char *name, const void *value,\ | |
454 | size_t size, int flags) \ | |
455 | { \ | |
744f52f9 Y |
456 | if (*name == '\0') \ |
457 | return -EINVAL; \ | |
5103e947 | 458 | return btrfs_xattr_set(inode, index, name, value, size, flags); \ |
69a32ac5 CM |
459 | } |
460 | ||
5103e947 JB |
461 | BTRFS_XATTR_SETGET_FUNCS(security, BTRFS_XATTR_INDEX_SECURITY); |
462 | BTRFS_XATTR_SETGET_FUNCS(system, BTRFS_XATTR_INDEX_SYSTEM); | |
463 | BTRFS_XATTR_SETGET_FUNCS(user, BTRFS_XATTR_INDEX_USER); | |
464 | BTRFS_XATTR_SETGET_FUNCS(trusted, BTRFS_XATTR_INDEX_TRUSTED); | |
465 | ||
466 | struct xattr_handler btrfs_xattr_security_handler = { | |
467 | .prefix = XATTR_SECURITY_PREFIX, | |
468 | .list = btrfs_xattr_generic_list, | |
469 | .get = btrfs_xattr_security_get, | |
470 | .set = btrfs_xattr_security_set, | |
471 | }; | |
472 | ||
473 | struct xattr_handler btrfs_xattr_system_handler = { | |
474 | .prefix = XATTR_SYSTEM_PREFIX, | |
475 | .list = btrfs_xattr_generic_list, | |
476 | .get = btrfs_xattr_system_get, | |
477 | .set = btrfs_xattr_system_set, | |
478 | }; | |
479 | ||
480 | struct xattr_handler btrfs_xattr_user_handler = { | |
481 | .prefix = XATTR_USER_PREFIX, | |
482 | .list = btrfs_xattr_generic_list, | |
483 | .get = btrfs_xattr_user_get, | |
484 | .set = btrfs_xattr_user_set, | |
485 | }; | |
486 | ||
487 | struct xattr_handler btrfs_xattr_trusted_handler = { | |
3acd7ee8 | 488 | .prefix = XATTR_TRUSTED_PREFIX, |
5103e947 JB |
489 | .list = btrfs_xattr_generic_list, |
490 | .get = btrfs_xattr_trusted_get, | |
491 | .set = btrfs_xattr_trusted_set, | |
492 | }; |