Merge branch 'stacking-fixes' (vfs stacking fixes from Jann)
[linux-2.6-block.git] / fs / f2fs / xattr.c
CommitLineData
0a8165d7 1/*
af48b85b
JK
2 * fs/f2fs/xattr.c
3 *
4 * Copyright (c) 2012 Samsung Electronics Co., Ltd.
5 * http://www.samsung.com/
6 *
7 * Portions of this code from linux/fs/ext2/xattr.c
8 *
9 * Copyright (C) 2001-2003 Andreas Gruenbacher <agruen@suse.de>
10 *
11 * Fix by Harrison Xing <harrison@mountainviewdata.com>.
12 * Extended attributes for symlinks and special files added per
13 * suggestion of Luka Renko <luka.renko@hermes.si>.
14 * xattr consolidation Copyright (c) 2004 James Morris <jmorris@redhat.com>,
15 * Red Hat Inc.
16 *
17 * This program is free software; you can redistribute it and/or modify
18 * it under the terms of the GNU General Public License version 2 as
19 * published by the Free Software Foundation.
20 */
21#include <linux/rwsem.h>
22#include <linux/f2fs_fs.h>
8ae8f162 23#include <linux/security.h>
a6dda0e6 24#include <linux/posix_acl_xattr.h>
af48b85b
JK
25#include "f2fs.h"
26#include "xattr.h"
27
d9a82a04 28static int f2fs_xattr_generic_get(const struct xattr_handler *handler,
b296821a
AV
29 struct dentry *unused, struct inode *inode,
30 const char *name, void *buffer, size_t size)
af48b85b 31{
b296821a 32 struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
af48b85b 33
d9a82a04 34 switch (handler->flags) {
af48b85b
JK
35 case F2FS_XATTR_INDEX_USER:
36 if (!test_opt(sbi, XATTR_USER))
37 return -EOPNOTSUPP;
38 break;
39 case F2FS_XATTR_INDEX_TRUSTED:
40 if (!capable(CAP_SYS_ADMIN))
41 return -EPERM;
42 break;
8ae8f162
JK
43 case F2FS_XATTR_INDEX_SECURITY:
44 break;
af48b85b
JK
45 default:
46 return -EINVAL;
47 }
b296821a 48 return f2fs_getxattr(inode, handler->flags, name,
d9a82a04 49 buffer, size, NULL);
af48b85b
JK
50}
51
d9a82a04 52static int f2fs_xattr_generic_set(const struct xattr_handler *handler,
59301226
AV
53 struct dentry *unused, struct inode *inode,
54 const char *name, const void *value,
d9a82a04 55 size_t size, int flags)
af48b85b 56{
59301226 57 struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
af48b85b 58
d9a82a04 59 switch (handler->flags) {
af48b85b
JK
60 case F2FS_XATTR_INDEX_USER:
61 if (!test_opt(sbi, XATTR_USER))
62 return -EOPNOTSUPP;
63 break;
64 case F2FS_XATTR_INDEX_TRUSTED:
65 if (!capable(CAP_SYS_ADMIN))
66 return -EPERM;
67 break;
8ae8f162
JK
68 case F2FS_XATTR_INDEX_SECURITY:
69 break;
af48b85b
JK
70 default:
71 return -EINVAL;
72 }
59301226 73 return f2fs_setxattr(inode, handler->flags, name,
c02745ef 74 value, size, NULL, flags);
af48b85b
JK
75}
76
764a5c6b 77static bool f2fs_xattr_user_list(struct dentry *dentry)
573ea5fc 78{
764a5c6b
AG
79 struct f2fs_sb_info *sbi = F2FS_SB(dentry->d_sb);
80
81 return test_opt(sbi, XATTR_USER);
82}
573ea5fc 83
764a5c6b
AG
84static bool f2fs_xattr_trusted_list(struct dentry *dentry)
85{
86 return capable(CAP_SYS_ADMIN);
573ea5fc
JK
87}
88
d9a82a04 89static int f2fs_xattr_advise_get(const struct xattr_handler *handler,
b296821a
AV
90 struct dentry *unused, struct inode *inode,
91 const char *name, void *buffer, size_t size)
573ea5fc 92{
84e97c27
CY
93 if (buffer)
94 *((char *)buffer) = F2FS_I(inode)->i_advise;
573ea5fc
JK
95 return sizeof(char);
96}
97
d9a82a04 98static int f2fs_xattr_advise_set(const struct xattr_handler *handler,
59301226
AV
99 struct dentry *unused, struct inode *inode,
100 const char *name, const void *value,
d9a82a04 101 size_t size, int flags)
573ea5fc 102{
573ea5fc
JK
103 if (!inode_owner_or_capable(inode))
104 return -EPERM;
105 if (value == NULL)
106 return -EINVAL;
107
108 F2FS_I(inode)->i_advise |= *(char *)value;
30c62fdb 109 mark_inode_dirty(inode);
573ea5fc
JK
110 return 0;
111}
112
8ae8f162
JK
113#ifdef CONFIG_F2FS_FS_SECURITY
114static int f2fs_initxattrs(struct inode *inode, const struct xattr *xattr_array,
115 void *page)
116{
117 const struct xattr *xattr;
118 int err = 0;
119
120 for (xattr = xattr_array; xattr->name != NULL; xattr++) {
d631abda 121 err = f2fs_setxattr(inode, F2FS_XATTR_INDEX_SECURITY,
8ae8f162 122 xattr->name, xattr->value,
c02745ef 123 xattr->value_len, (struct page *)page, 0);
8ae8f162
JK
124 if (err < 0)
125 break;
126 }
127 return err;
128}
129
130int f2fs_init_security(struct inode *inode, struct inode *dir,
131 const struct qstr *qstr, struct page *ipage)
132{
133 return security_inode_init_security(inode, dir, qstr,
134 &f2fs_initxattrs, ipage);
135}
136#endif
137
af48b85b
JK
138const struct xattr_handler f2fs_xattr_user_handler = {
139 .prefix = XATTR_USER_PREFIX,
140 .flags = F2FS_XATTR_INDEX_USER,
764a5c6b 141 .list = f2fs_xattr_user_list,
af48b85b
JK
142 .get = f2fs_xattr_generic_get,
143 .set = f2fs_xattr_generic_set,
144};
145
146const struct xattr_handler f2fs_xattr_trusted_handler = {
147 .prefix = XATTR_TRUSTED_PREFIX,
148 .flags = F2FS_XATTR_INDEX_TRUSTED,
764a5c6b 149 .list = f2fs_xattr_trusted_list,
af48b85b
JK
150 .get = f2fs_xattr_generic_get,
151 .set = f2fs_xattr_generic_set,
152};
153
573ea5fc 154const struct xattr_handler f2fs_xattr_advise_handler = {
98e9cb57 155 .name = F2FS_SYSTEM_ADVISE_NAME,
573ea5fc 156 .flags = F2FS_XATTR_INDEX_ADVISE,
573ea5fc
JK
157 .get = f2fs_xattr_advise_get,
158 .set = f2fs_xattr_advise_set,
159};
160
8ae8f162
JK
161const struct xattr_handler f2fs_xattr_security_handler = {
162 .prefix = XATTR_SECURITY_PREFIX,
163 .flags = F2FS_XATTR_INDEX_SECURITY,
8ae8f162
JK
164 .get = f2fs_xattr_generic_get,
165 .set = f2fs_xattr_generic_set,
166};
167
af48b85b
JK
168static const struct xattr_handler *f2fs_xattr_handler_map[] = {
169 [F2FS_XATTR_INDEX_USER] = &f2fs_xattr_user_handler,
170#ifdef CONFIG_F2FS_FS_POSIX_ACL
a6dda0e6
CH
171 [F2FS_XATTR_INDEX_POSIX_ACL_ACCESS] = &posix_acl_access_xattr_handler,
172 [F2FS_XATTR_INDEX_POSIX_ACL_DEFAULT] = &posix_acl_default_xattr_handler,
af48b85b
JK
173#endif
174 [F2FS_XATTR_INDEX_TRUSTED] = &f2fs_xattr_trusted_handler,
8ae8f162
JK
175#ifdef CONFIG_F2FS_FS_SECURITY
176 [F2FS_XATTR_INDEX_SECURITY] = &f2fs_xattr_security_handler,
177#endif
af48b85b
JK
178 [F2FS_XATTR_INDEX_ADVISE] = &f2fs_xattr_advise_handler,
179};
180
181const struct xattr_handler *f2fs_xattr_handlers[] = {
182 &f2fs_xattr_user_handler,
183#ifdef CONFIG_F2FS_FS_POSIX_ACL
a6dda0e6
CH
184 &posix_acl_access_xattr_handler,
185 &posix_acl_default_xattr_handler,
af48b85b
JK
186#endif
187 &f2fs_xattr_trusted_handler,
8ae8f162
JK
188#ifdef CONFIG_F2FS_FS_SECURITY
189 &f2fs_xattr_security_handler,
190#endif
af48b85b
JK
191 &f2fs_xattr_advise_handler,
192 NULL,
193};
194
e1123268 195static inline const struct xattr_handler *f2fs_xattr_handler(int index)
af48b85b
JK
196{
197 const struct xattr_handler *handler = NULL;
198
e1123268
JK
199 if (index > 0 && index < ARRAY_SIZE(f2fs_xattr_handler_map))
200 handler = f2fs_xattr_handler_map[index];
af48b85b
JK
201 return handler;
202}
203
e1123268
JK
204static struct f2fs_xattr_entry *__find_xattr(void *base_addr, int index,
205 size_t len, const char *name)
dd9cfe23
JK
206{
207 struct f2fs_xattr_entry *entry;
208
209 list_for_each_xattr(entry, base_addr) {
e1123268 210 if (entry->e_name_index != index)
dd9cfe23 211 continue;
e1123268 212 if (entry->e_name_len != len)
dd9cfe23 213 continue;
e1123268 214 if (!memcmp(entry->e_name, name, len))
dd9cfe23
JK
215 break;
216 }
217 return entry;
218}
219
65985d93
JK
220static void *read_all_xattrs(struct inode *inode, struct page *ipage)
221{
4081363f 222 struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
65985d93
JK
223 struct f2fs_xattr_header *header;
224 size_t size = PAGE_SIZE, inline_size = 0;
225 void *txattr_addr;
226
227 inline_size = inline_xattr_size(inode);
228
808a1d74 229 txattr_addr = kzalloc(inline_size + size, GFP_F2FS_ZERO);
65985d93
JK
230 if (!txattr_addr)
231 return NULL;
232
233 /* read from inline xattr */
234 if (inline_size) {
235 struct page *page = NULL;
236 void *inline_addr;
237
238 if (ipage) {
239 inline_addr = inline_xattr_addr(ipage);
240 } else {
241 page = get_node_page(sbi, inode->i_ino);
242 if (IS_ERR(page))
243 goto fail;
244 inline_addr = inline_xattr_addr(page);
245 }
246 memcpy(txattr_addr, inline_addr, inline_size);
247 f2fs_put_page(page, 1);
248 }
249
250 /* read from xattr node block */
251 if (F2FS_I(inode)->i_xattr_nid) {
252 struct page *xpage;
253 void *xattr_addr;
254
255 /* The inode already has an extended attribute block. */
256 xpage = get_node_page(sbi, F2FS_I(inode)->i_xattr_nid);
257 if (IS_ERR(xpage))
258 goto fail;
259
260 xattr_addr = page_address(xpage);
261 memcpy(txattr_addr + inline_size, xattr_addr, PAGE_SIZE);
262 f2fs_put_page(xpage, 1);
263 }
264
265 header = XATTR_HDR(txattr_addr);
266
267 /* never been allocated xattrs */
268 if (le32_to_cpu(header->h_magic) != F2FS_XATTR_MAGIC) {
269 header->h_magic = cpu_to_le32(F2FS_XATTR_MAGIC);
270 header->h_refcount = cpu_to_le32(1);
271 }
272 return txattr_addr;
273fail:
274 kzfree(txattr_addr);
275 return NULL;
276}
277
278static inline int write_all_xattrs(struct inode *inode, __u32 hsize,
279 void *txattr_addr, struct page *ipage)
280{
4081363f 281 struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
65985d93
JK
282 size_t inline_size = 0;
283 void *xattr_addr;
284 struct page *xpage;
285 nid_t new_nid = 0;
286 int err;
287
288 inline_size = inline_xattr_size(inode);
289
290 if (hsize > inline_size && !F2FS_I(inode)->i_xattr_nid)
291 if (!alloc_nid(sbi, &new_nid))
292 return -ENOSPC;
293
294 /* write to inline xattr */
295 if (inline_size) {
296 struct page *page = NULL;
297 void *inline_addr;
298
299 if (ipage) {
300 inline_addr = inline_xattr_addr(ipage);
fec1d657 301 f2fs_wait_on_page_writeback(ipage, NODE, true);
65985d93
JK
302 } else {
303 page = get_node_page(sbi, inode->i_ino);
304 if (IS_ERR(page)) {
305 alloc_nid_failed(sbi, new_nid);
306 return PTR_ERR(page);
307 }
308 inline_addr = inline_xattr_addr(page);
fec1d657 309 f2fs_wait_on_page_writeback(page, NODE, true);
65985d93
JK
310 }
311 memcpy(inline_addr, txattr_addr, inline_size);
312 f2fs_put_page(page, 1);
313
314 /* no need to use xattr node block */
315 if (hsize <= inline_size) {
316 err = truncate_xattr_node(inode, ipage);
317 alloc_nid_failed(sbi, new_nid);
318 return err;
319 }
320 }
321
322 /* write to xattr node block */
323 if (F2FS_I(inode)->i_xattr_nid) {
324 xpage = get_node_page(sbi, F2FS_I(inode)->i_xattr_nid);
325 if (IS_ERR(xpage)) {
326 alloc_nid_failed(sbi, new_nid);
327 return PTR_ERR(xpage);
328 }
9850cf4a 329 f2fs_bug_on(sbi, new_nid);
fec1d657 330 f2fs_wait_on_page_writeback(xpage, NODE, true);
65985d93
JK
331 } else {
332 struct dnode_of_data dn;
333 set_new_dnode(&dn, inode, NULL, NULL, new_nid);
334 xpage = new_node_page(&dn, XATTR_NODE_OFFSET, ipage);
335 if (IS_ERR(xpage)) {
336 alloc_nid_failed(sbi, new_nid);
337 return PTR_ERR(xpage);
338 }
339 alloc_nid_done(sbi, new_nid);
340 }
341
342 xattr_addr = page_address(xpage);
343 memcpy(xattr_addr, txattr_addr + inline_size, PAGE_SIZE -
344 sizeof(struct node_footer));
345 set_page_dirty(xpage);
346 f2fs_put_page(xpage, 1);
347
348 /* need to checkpoint during fsync */
349 F2FS_I(inode)->xattr_ver = cur_cp_version(F2FS_CKPT(sbi));
350 return 0;
351}
352
e1123268 353int f2fs_getxattr(struct inode *inode, int index, const char *name,
bce8d112 354 void *buffer, size_t buffer_size, struct page *ipage)
af48b85b 355{
af48b85b 356 struct f2fs_xattr_entry *entry;
65985d93 357 void *base_addr;
dd9cfe23 358 int error = 0;
e1123268 359 size_t size, len;
af48b85b
JK
360
361 if (name == NULL)
362 return -EINVAL;
e1123268
JK
363
364 len = strlen(name);
365 if (len > F2FS_NAME_LEN)
6e452d69 366 return -ERANGE;
af48b85b 367
bce8d112 368 base_addr = read_all_xattrs(inode, ipage);
65985d93
JK
369 if (!base_addr)
370 return -ENOMEM;
af48b85b 371
e1123268 372 entry = __find_xattr(base_addr, index, len, name);
dd9cfe23 373 if (IS_XATTR_LAST_ENTRY(entry)) {
af48b85b
JK
374 error = -ENODATA;
375 goto cleanup;
376 }
377
e1123268 378 size = le16_to_cpu(entry->e_value_size);
af48b85b 379
e1123268 380 if (buffer && size > buffer_size) {
af48b85b
JK
381 error = -ERANGE;
382 goto cleanup;
383 }
384
385 if (buffer) {
386 char *pval = entry->e_name + entry->e_name_len;
e1123268 387 memcpy(buffer, pval, size);
af48b85b 388 }
e1123268 389 error = size;
af48b85b
JK
390
391cleanup:
65985d93 392 kzfree(base_addr);
af48b85b
JK
393 return error;
394}
395
396ssize_t f2fs_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size)
397{
2b0143b5 398 struct inode *inode = d_inode(dentry);
af48b85b 399 struct f2fs_xattr_entry *entry;
af48b85b
JK
400 void *base_addr;
401 int error = 0;
402 size_t rest = buffer_size;
403
65985d93
JK
404 base_addr = read_all_xattrs(inode, NULL);
405 if (!base_addr)
406 return -ENOMEM;
af48b85b
JK
407
408 list_for_each_xattr(entry, base_addr) {
409 const struct xattr_handler *handler =
410 f2fs_xattr_handler(entry->e_name_index);
764a5c6b
AG
411 const char *prefix;
412 size_t prefix_len;
af48b85b
JK
413 size_t size;
414
764a5c6b 415 if (!handler || (handler->list && !handler->list(dentry)))
af48b85b
JK
416 continue;
417
764a5c6b
AG
418 prefix = handler->prefix ?: handler->name;
419 prefix_len = strlen(prefix);
420 size = prefix_len + entry->e_name_len + 1;
421 if (buffer) {
422 if (size > rest) {
423 error = -ERANGE;
424 goto cleanup;
425 }
426 memcpy(buffer, prefix, prefix_len);
427 buffer += prefix_len;
428 memcpy(buffer, entry->e_name, entry->e_name_len);
429 buffer += entry->e_name_len;
430 *buffer++ = 0;
af48b85b 431 }
af48b85b
JK
432 rest -= size;
433 }
434 error = buffer_size - rest;
435cleanup:
65985d93 436 kzfree(base_addr);
af48b85b
JK
437 return error;
438}
439
e1123268
JK
440static int __f2fs_setxattr(struct inode *inode, int index,
441 const char *name, const void *value, size_t size,
c02745ef 442 struct page *ipage, int flags)
af48b85b 443{
af48b85b 444 struct f2fs_inode_info *fi = F2FS_I(inode);
af48b85b 445 struct f2fs_xattr_entry *here, *last;
af48b85b 446 void *base_addr;
65985d93 447 int found, newsize;
e1123268 448 size_t len;
65985d93
JK
449 __u32 new_hsize;
450 int error = -ENOMEM;
af48b85b
JK
451
452 if (name == NULL)
453 return -EINVAL;
af48b85b
JK
454
455 if (value == NULL)
e1123268 456 size = 0;
af48b85b 457
e1123268 458 len = strlen(name);
7c909772 459
037fe70c 460 if (len > F2FS_NAME_LEN)
af48b85b
JK
461 return -ERANGE;
462
037fe70c
CY
463 if (size > MAX_VALUE_LEN(inode))
464 return -E2BIG;
465
65985d93
JK
466 base_addr = read_all_xattrs(inode, ipage);
467 if (!base_addr)
468 goto exit;
af48b85b
JK
469
470 /* find entry with wanted name. */
e1123268 471 here = __find_xattr(base_addr, index, len, name);
af48b85b 472
dd9cfe23 473 found = IS_XATTR_LAST_ENTRY(here) ? 0 : 1;
af48b85b 474
916decbf
JK
475 if ((flags & XATTR_REPLACE) && !found) {
476 error = -ENODATA;
477 goto exit;
478 } else if ((flags & XATTR_CREATE) && found) {
479 error = -EEXIST;
480 goto exit;
481 }
482
483 last = here;
af48b85b
JK
484 while (!IS_XATTR_LAST_ENTRY(last))
485 last = XATTR_NEXT_ENTRY(last);
486
e1123268 487 newsize = XATTR_ALIGN(sizeof(struct f2fs_xattr_entry) + len + size);
af48b85b
JK
488
489 /* 1. Check space */
490 if (value) {
65985d93
JK
491 int free;
492 /*
493 * If value is NULL, it is remove operation.
e1c42045 494 * In case of update operation, we calculate free.
af48b85b 495 */
65985d93 496 free = MIN_OFFSET(inode) - ((char *)last - (char *)base_addr);
af48b85b 497 if (found)
cc3de6a3 498 free = free + ENTRY_SIZE(here);
af48b85b 499
6bacf52f 500 if (unlikely(free < newsize)) {
58457f1c 501 error = -E2BIG;
65985d93 502 goto exit;
af48b85b
JK
503 }
504 }
505
506 /* 2. Remove old entry */
507 if (found) {
65985d93
JK
508 /*
509 * If entry is found, remove old entry.
af48b85b
JK
510 * If not found, remove operation is not needed.
511 */
512 struct f2fs_xattr_entry *next = XATTR_NEXT_ENTRY(here);
513 int oldsize = ENTRY_SIZE(here);
514
515 memmove(here, next, (char *)last - (char *)next);
516 last = (struct f2fs_xattr_entry *)((char *)last - oldsize);
517 memset(last, 0, oldsize);
518 }
519
65985d93
JK
520 new_hsize = (char *)last - (char *)base_addr;
521
af48b85b
JK
522 /* 3. Write new entry */
523 if (value) {
65985d93
JK
524 char *pval;
525 /*
526 * Before we come here, old entry is removed.
527 * We just write new entry.
528 */
e1123268
JK
529 last->e_name_index = index;
530 last->e_name_len = len;
531 memcpy(last->e_name, name, len);
532 pval = last->e_name + len;
533 memcpy(pval, value, size);
534 last->e_value_size = cpu_to_le16(size);
65985d93 535 new_hsize += newsize;
af48b85b
JK
536 }
537
65985d93
JK
538 error = write_all_xattrs(inode, new_hsize, base_addr, ipage);
539 if (error)
540 goto exit;
af48b85b
JK
541
542 if (is_inode_flag_set(fi, FI_ACL_MODE)) {
543 inode->i_mode = fi->i_acl_mode;
544 inode->i_ctime = CURRENT_TIME;
545 clear_inode_flag(fi, FI_ACL_MODE);
546 }
f424f664
JK
547 if (index == F2FS_XATTR_INDEX_ENCRYPTION &&
548 !strcmp(name, F2FS_XATTR_NAME_ENCRYPTION_CONTEXT))
549 f2fs_set_encrypted_inode(inode);
e518ff81 550
8ae8f162
JK
551 if (ipage)
552 update_inode(inode, ipage);
553 else
554 update_inode_page(inode);
7c909772 555exit:
65985d93 556 kzfree(base_addr);
af48b85b
JK
557 return error;
558}
52ab9560 559
e1123268
JK
560int f2fs_setxattr(struct inode *inode, int index, const char *name,
561 const void *value, size_t size,
c02745ef 562 struct page *ipage, int flags)
52ab9560 563{
4081363f 564 struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
52ab9560
RK
565 int err;
566
d631abda
JK
567 /* this case is only from init_inode_metadata */
568 if (ipage)
569 return __f2fs_setxattr(inode, index, name, value,
570 size, ipage, flags);
2c4db1a6 571 f2fs_balance_fs(sbi, true);
52ab9560 572
e479556b 573 f2fs_lock_op(sbi);
d928bfbf
JK
574 /* protect xattr_ver */
575 down_write(&F2FS_I(inode)->i_sem);
c02745ef 576 err = __f2fs_setxattr(inode, index, name, value, size, ipage, flags);
d928bfbf 577 up_write(&F2FS_I(inode)->i_sem);
e479556b 578 f2fs_unlock_op(sbi);
52ab9560 579
d0239e1b 580 f2fs_update_time(sbi, REQ_TIME);
52ab9560
RK
581 return err;
582}