diff options
Diffstat (limited to 'fs/ext2/xattr.c')
-rw-r--r-- | fs/ext2/xattr.c | 1043 |
1 files changed, 1043 insertions, 0 deletions
diff --git a/fs/ext2/xattr.c b/fs/ext2/xattr.c new file mode 100644 index 000000000000..27982b500e84 --- /dev/null +++ b/fs/ext2/xattr.c | |||
@@ -0,0 +1,1043 @@ | |||
1 | /* | ||
2 | * linux/fs/ext2/xattr.c | ||
3 | * | ||
4 | * Copyright (C) 2001-2003 Andreas Gruenbacher <agruen@suse.de> | ||
5 | * | ||
6 | * Fix by Harrison Xing <harrison@mountainviewdata.com>. | ||
7 | * Extended attributes for symlinks and special files added per | ||
8 | * suggestion of Luka Renko <luka.renko@hermes.si>. | ||
9 | * xattr consolidation Copyright (c) 2004 James Morris <jmorris@redhat.com>, | ||
10 | * Red Hat Inc. | ||
11 | * | ||
12 | */ | ||
13 | |||
14 | /* | ||
15 | * Extended attributes are stored on disk blocks allocated outside of | ||
16 | * any inode. The i_file_acl field is then made to point to this allocated | ||
17 | * block. If all extended attributes of an inode are identical, these | ||
18 | * inodes may share the same extended attribute block. Such situations | ||
19 | * are automatically detected by keeping a cache of recent attribute block | ||
20 | * numbers and hashes over the block's contents in memory. | ||
21 | * | ||
22 | * | ||
23 | * Extended attribute block layout: | ||
24 | * | ||
25 | * +------------------+ | ||
26 | * | header | | ||
27 | * | entry 1 | | | ||
28 | * | entry 2 | | growing downwards | ||
29 | * | entry 3 | v | ||
30 | * | four null bytes | | ||
31 | * | . . . | | ||
32 | * | value 1 | ^ | ||
33 | * | value 3 | | growing upwards | ||
34 | * | value 2 | | | ||
35 | * +------------------+ | ||
36 | * | ||
37 | * The block header is followed by multiple entry descriptors. These entry | ||
38 | * descriptors are variable in size, and alligned to EXT2_XATTR_PAD | ||
39 | * byte boundaries. The entry descriptors are sorted by attribute name, | ||
40 | * so that two extended attribute blocks can be compared efficiently. | ||
41 | * | ||
42 | * Attribute values are aligned to the end of the block, stored in | ||
43 | * no specific order. They are also padded to EXT2_XATTR_PAD byte | ||
44 | * boundaries. No additional gaps are left between them. | ||
45 | * | ||
46 | * Locking strategy | ||
47 | * ---------------- | ||
48 | * EXT2_I(inode)->i_file_acl is protected by EXT2_I(inode)->xattr_sem. | ||
49 | * EA blocks are only changed if they are exclusive to an inode, so | ||
50 | * holding xattr_sem also means that nothing but the EA block's reference | ||
51 | * count will change. Multiple writers to an EA block are synchronized | ||
52 | * by the bh lock. No more than a single bh lock is held at any time | ||
53 | * to avoid deadlocks. | ||
54 | */ | ||
55 | |||
56 | #include <linux/buffer_head.h> | ||
57 | #include <linux/module.h> | ||
58 | #include <linux/init.h> | ||
59 | #include <linux/slab.h> | ||
60 | #include <linux/mbcache.h> | ||
61 | #include <linux/quotaops.h> | ||
62 | #include <linux/rwsem.h> | ||
63 | #include "ext2.h" | ||
64 | #include "xattr.h" | ||
65 | #include "acl.h" | ||
66 | |||
67 | #define HDR(bh) ((struct ext2_xattr_header *)((bh)->b_data)) | ||
68 | #define ENTRY(ptr) ((struct ext2_xattr_entry *)(ptr)) | ||
69 | #define FIRST_ENTRY(bh) ENTRY(HDR(bh)+1) | ||
70 | #define IS_LAST_ENTRY(entry) (*(__u32 *)(entry) == 0) | ||
71 | |||
72 | #ifdef EXT2_XATTR_DEBUG | ||
73 | # define ea_idebug(inode, f...) do { \ | ||
74 | printk(KERN_DEBUG "inode %s:%ld: ", \ | ||
75 | inode->i_sb->s_id, inode->i_ino); \ | ||
76 | printk(f); \ | ||
77 | printk("\n"); \ | ||
78 | } while (0) | ||
79 | # define ea_bdebug(bh, f...) do { \ | ||
80 | char b[BDEVNAME_SIZE]; \ | ||
81 | printk(KERN_DEBUG "block %s:%lu: ", \ | ||
82 | bdevname(bh->b_bdev, b), \ | ||
83 | (unsigned long) bh->b_blocknr); \ | ||
84 | printk(f); \ | ||
85 | printk("\n"); \ | ||
86 | } while (0) | ||
87 | #else | ||
88 | # define ea_idebug(f...) | ||
89 | # define ea_bdebug(f...) | ||
90 | #endif | ||
91 | |||
92 | static int ext2_xattr_set2(struct inode *, struct buffer_head *, | ||
93 | struct ext2_xattr_header *); | ||
94 | |||
95 | static int ext2_xattr_cache_insert(struct buffer_head *); | ||
96 | static struct buffer_head *ext2_xattr_cache_find(struct inode *, | ||
97 | struct ext2_xattr_header *); | ||
98 | static void ext2_xattr_rehash(struct ext2_xattr_header *, | ||
99 | struct ext2_xattr_entry *); | ||
100 | |||
101 | static struct mb_cache *ext2_xattr_cache; | ||
102 | |||
103 | static struct xattr_handler *ext2_xattr_handler_map[] = { | ||
104 | [EXT2_XATTR_INDEX_USER] = &ext2_xattr_user_handler, | ||
105 | #ifdef CONFIG_EXT2_FS_POSIX_ACL | ||
106 | [EXT2_XATTR_INDEX_POSIX_ACL_ACCESS] = &ext2_xattr_acl_access_handler, | ||
107 | [EXT2_XATTR_INDEX_POSIX_ACL_DEFAULT] = &ext2_xattr_acl_default_handler, | ||
108 | #endif | ||
109 | [EXT2_XATTR_INDEX_TRUSTED] = &ext2_xattr_trusted_handler, | ||
110 | #ifdef CONFIG_EXT2_FS_SECURITY | ||
111 | [EXT2_XATTR_INDEX_SECURITY] = &ext2_xattr_security_handler, | ||
112 | #endif | ||
113 | }; | ||
114 | |||
115 | struct xattr_handler *ext2_xattr_handlers[] = { | ||
116 | &ext2_xattr_user_handler, | ||
117 | &ext2_xattr_trusted_handler, | ||
118 | #ifdef CONFIG_EXT2_FS_POSIX_ACL | ||
119 | &ext2_xattr_acl_access_handler, | ||
120 | &ext2_xattr_acl_default_handler, | ||
121 | #endif | ||
122 | #ifdef CONFIG_EXT2_FS_SECURITY | ||
123 | &ext2_xattr_security_handler, | ||
124 | #endif | ||
125 | NULL | ||
126 | }; | ||
127 | |||
128 | static inline struct xattr_handler * | ||
129 | ext2_xattr_handler(int name_index) | ||
130 | { | ||
131 | struct xattr_handler *handler = NULL; | ||
132 | |||
133 | if (name_index > 0 && name_index < ARRAY_SIZE(ext2_xattr_handler_map)) | ||
134 | handler = ext2_xattr_handler_map[name_index]; | ||
135 | return handler; | ||
136 | } | ||
137 | |||
138 | /* | ||
139 | * ext2_xattr_get() | ||
140 | * | ||
141 | * Copy an extended attribute into the buffer | ||
142 | * provided, or compute the buffer size required. | ||
143 | * Buffer is NULL to compute the size of the buffer required. | ||
144 | * | ||
145 | * Returns a negative error number on failure, or the number of bytes | ||
146 | * used / required on success. | ||
147 | */ | ||
148 | int | ||
149 | ext2_xattr_get(struct inode *inode, int name_index, const char *name, | ||
150 | void *buffer, size_t buffer_size) | ||
151 | { | ||
152 | struct buffer_head *bh = NULL; | ||
153 | struct ext2_xattr_entry *entry; | ||
154 | size_t name_len, size; | ||
155 | char *end; | ||
156 | int error; | ||
157 | |||
158 | ea_idebug(inode, "name=%d.%s, buffer=%p, buffer_size=%ld", | ||
159 | name_index, name, buffer, (long)buffer_size); | ||
160 | |||
161 | if (name == NULL) | ||
162 | return -EINVAL; | ||
163 | down_read(&EXT2_I(inode)->xattr_sem); | ||
164 | error = -ENODATA; | ||
165 | if (!EXT2_I(inode)->i_file_acl) | ||
166 | goto cleanup; | ||
167 | ea_idebug(inode, "reading block %d", EXT2_I(inode)->i_file_acl); | ||
168 | bh = sb_bread(inode->i_sb, EXT2_I(inode)->i_file_acl); | ||
169 | error = -EIO; | ||
170 | if (!bh) | ||
171 | goto cleanup; | ||
172 | ea_bdebug(bh, "b_count=%d, refcount=%d", | ||
173 | atomic_read(&(bh->b_count)), le32_to_cpu(HDR(bh)->h_refcount)); | ||
174 | end = bh->b_data + bh->b_size; | ||
175 | if (HDR(bh)->h_magic != cpu_to_le32(EXT2_XATTR_MAGIC) || | ||
176 | HDR(bh)->h_blocks != cpu_to_le32(1)) { | ||
177 | bad_block: ext2_error(inode->i_sb, "ext2_xattr_get", | ||
178 | "inode %ld: bad block %d", inode->i_ino, | ||
179 | EXT2_I(inode)->i_file_acl); | ||
180 | error = -EIO; | ||
181 | goto cleanup; | ||
182 | } | ||
183 | /* find named attribute */ | ||
184 | name_len = strlen(name); | ||
185 | |||
186 | error = -ERANGE; | ||
187 | if (name_len > 255) | ||
188 | goto cleanup; | ||
189 | entry = FIRST_ENTRY(bh); | ||
190 | while (!IS_LAST_ENTRY(entry)) { | ||
191 | struct ext2_xattr_entry *next = | ||
192 | EXT2_XATTR_NEXT(entry); | ||
193 | if ((char *)next >= end) | ||
194 | goto bad_block; | ||
195 | if (name_index == entry->e_name_index && | ||
196 | name_len == entry->e_name_len && | ||
197 | memcmp(name, entry->e_name, name_len) == 0) | ||
198 | goto found; | ||
199 | entry = next; | ||
200 | } | ||
201 | /* Check the remaining name entries */ | ||
202 | while (!IS_LAST_ENTRY(entry)) { | ||
203 | struct ext2_xattr_entry *next = | ||
204 | EXT2_XATTR_NEXT(entry); | ||
205 | if ((char *)next >= end) | ||
206 | goto bad_block; | ||
207 | entry = next; | ||
208 | } | ||
209 | if (ext2_xattr_cache_insert(bh)) | ||
210 | ea_idebug(inode, "cache insert failed"); | ||
211 | error = -ENODATA; | ||
212 | goto cleanup; | ||
213 | found: | ||
214 | /* check the buffer size */ | ||
215 | if (entry->e_value_block != 0) | ||
216 | goto bad_block; | ||
217 | size = le32_to_cpu(entry->e_value_size); | ||
218 | if (size > inode->i_sb->s_blocksize || | ||
219 | le16_to_cpu(entry->e_value_offs) + size > inode->i_sb->s_blocksize) | ||
220 | goto bad_block; | ||
221 | |||
222 | if (ext2_xattr_cache_insert(bh)) | ||
223 | ea_idebug(inode, "cache insert failed"); | ||
224 | if (buffer) { | ||
225 | error = -ERANGE; | ||
226 | if (size > buffer_size) | ||
227 | goto cleanup; | ||
228 | /* return value of attribute */ | ||
229 | memcpy(buffer, bh->b_data + le16_to_cpu(entry->e_value_offs), | ||
230 | size); | ||
231 | } | ||
232 | error = size; | ||
233 | |||
234 | cleanup: | ||
235 | brelse(bh); | ||
236 | up_read(&EXT2_I(inode)->xattr_sem); | ||
237 | |||
238 | return error; | ||
239 | } | ||
240 | |||
241 | /* | ||
242 | * ext2_xattr_list() | ||
243 | * | ||
244 | * Copy a list of attribute names into the buffer | ||
245 | * provided, or compute the buffer size required. | ||
246 | * Buffer is NULL to compute the size of the buffer required. | ||
247 | * | ||
248 | * Returns a negative error number on failure, or the number of bytes | ||
249 | * used / required on success. | ||
250 | */ | ||
251 | static int | ||
252 | ext2_xattr_list(struct inode *inode, char *buffer, size_t buffer_size) | ||
253 | { | ||
254 | struct buffer_head *bh = NULL; | ||
255 | struct ext2_xattr_entry *entry; | ||
256 | char *end; | ||
257 | size_t rest = buffer_size; | ||
258 | int error; | ||
259 | |||
260 | ea_idebug(inode, "buffer=%p, buffer_size=%ld", | ||
261 | buffer, (long)buffer_size); | ||
262 | |||
263 | down_read(&EXT2_I(inode)->xattr_sem); | ||
264 | error = 0; | ||
265 | if (!EXT2_I(inode)->i_file_acl) | ||
266 | goto cleanup; | ||
267 | ea_idebug(inode, "reading block %d", EXT2_I(inode)->i_file_acl); | ||
268 | bh = sb_bread(inode->i_sb, EXT2_I(inode)->i_file_acl); | ||
269 | error = -EIO; | ||
270 | if (!bh) | ||
271 | goto cleanup; | ||
272 | ea_bdebug(bh, "b_count=%d, refcount=%d", | ||
273 | atomic_read(&(bh->b_count)), le32_to_cpu(HDR(bh)->h_refcount)); | ||
274 | end = bh->b_data + bh->b_size; | ||
275 | if (HDR(bh)->h_magic != cpu_to_le32(EXT2_XATTR_MAGIC) || | ||
276 | HDR(bh)->h_blocks != cpu_to_le32(1)) { | ||
277 | bad_block: ext2_error(inode->i_sb, "ext2_xattr_list", | ||
278 | "inode %ld: bad block %d", inode->i_ino, | ||
279 | EXT2_I(inode)->i_file_acl); | ||
280 | error = -EIO; | ||
281 | goto cleanup; | ||
282 | } | ||
283 | |||
284 | /* check the on-disk data structure */ | ||
285 | entry = FIRST_ENTRY(bh); | ||
286 | while (!IS_LAST_ENTRY(entry)) { | ||
287 | struct ext2_xattr_entry *next = EXT2_XATTR_NEXT(entry); | ||
288 | |||
289 | if ((char *)next >= end) | ||
290 | goto bad_block; | ||
291 | entry = next; | ||
292 | } | ||
293 | if (ext2_xattr_cache_insert(bh)) | ||
294 | ea_idebug(inode, "cache insert failed"); | ||
295 | |||
296 | /* list the attribute names */ | ||
297 | for (entry = FIRST_ENTRY(bh); !IS_LAST_ENTRY(entry); | ||
298 | entry = EXT2_XATTR_NEXT(entry)) { | ||
299 | struct xattr_handler *handler = | ||
300 | ext2_xattr_handler(entry->e_name_index); | ||
301 | |||
302 | if (handler) { | ||
303 | size_t size = handler->list(inode, buffer, rest, | ||
304 | entry->e_name, | ||
305 | entry->e_name_len); | ||
306 | if (buffer) { | ||
307 | if (size > rest) { | ||
308 | error = -ERANGE; | ||
309 | goto cleanup; | ||
310 | } | ||
311 | buffer += size; | ||
312 | } | ||
313 | rest -= size; | ||
314 | } | ||
315 | } | ||
316 | error = buffer_size - rest; /* total size */ | ||
317 | |||
318 | cleanup: | ||
319 | brelse(bh); | ||
320 | up_read(&EXT2_I(inode)->xattr_sem); | ||
321 | |||
322 | return error; | ||
323 | } | ||
324 | |||
325 | /* | ||
326 | * Inode operation listxattr() | ||
327 | * | ||
328 | * dentry->d_inode->i_sem: don't care | ||
329 | */ | ||
330 | ssize_t | ||
331 | ext2_listxattr(struct dentry *dentry, char *buffer, size_t size) | ||
332 | { | ||
333 | return ext2_xattr_list(dentry->d_inode, buffer, size); | ||
334 | } | ||
335 | |||
336 | /* | ||
337 | * If the EXT2_FEATURE_COMPAT_EXT_ATTR feature of this file system is | ||
338 | * not set, set it. | ||
339 | */ | ||
340 | static void ext2_xattr_update_super_block(struct super_block *sb) | ||
341 | { | ||
342 | if (EXT2_HAS_COMPAT_FEATURE(sb, EXT2_FEATURE_COMPAT_EXT_ATTR)) | ||
343 | return; | ||
344 | |||
345 | lock_super(sb); | ||
346 | EXT2_SB(sb)->s_es->s_feature_compat |= | ||
347 | cpu_to_le32(EXT2_FEATURE_COMPAT_EXT_ATTR); | ||
348 | sb->s_dirt = 1; | ||
349 | mark_buffer_dirty(EXT2_SB(sb)->s_sbh); | ||
350 | unlock_super(sb); | ||
351 | } | ||
352 | |||
353 | /* | ||
354 | * ext2_xattr_set() | ||
355 | * | ||
356 | * Create, replace or remove an extended attribute for this inode. Buffer | ||
357 | * is NULL to remove an existing extended attribute, and non-NULL to | ||
358 | * either replace an existing extended attribute, or create a new extended | ||
359 | * attribute. The flags XATTR_REPLACE and XATTR_CREATE | ||
360 | * specify that an extended attribute must exist and must not exist | ||
361 | * previous to the call, respectively. | ||
362 | * | ||
363 | * Returns 0, or a negative error number on failure. | ||
364 | */ | ||
365 | int | ||
366 | ext2_xattr_set(struct inode *inode, int name_index, const char *name, | ||
367 | const void *value, size_t value_len, int flags) | ||
368 | { | ||
369 | struct super_block *sb = inode->i_sb; | ||
370 | struct buffer_head *bh = NULL; | ||
371 | struct ext2_xattr_header *header = NULL; | ||
372 | struct ext2_xattr_entry *here, *last; | ||
373 | size_t name_len, free, min_offs = sb->s_blocksize; | ||
374 | int not_found = 1, error; | ||
375 | char *end; | ||
376 | |||
377 | /* | ||
378 | * header -- Points either into bh, or to a temporarily | ||
379 | * allocated buffer. | ||
380 | * here -- The named entry found, or the place for inserting, within | ||
381 | * the block pointed to by header. | ||
382 | * last -- Points right after the last named entry within the block | ||
383 | * pointed to by header. | ||
384 | * min_offs -- The offset of the first value (values are aligned | ||
385 | * towards the end of the block). | ||
386 | * end -- Points right after the block pointed to by header. | ||
387 | */ | ||
388 | |||
389 | ea_idebug(inode, "name=%d.%s, value=%p, value_len=%ld", | ||
390 | name_index, name, value, (long)value_len); | ||
391 | |||
392 | if (IS_RDONLY(inode)) | ||
393 | return -EROFS; | ||
394 | if (IS_IMMUTABLE(inode) || IS_APPEND(inode)) | ||
395 | return -EPERM; | ||
396 | if (value == NULL) | ||
397 | value_len = 0; | ||
398 | if (name == NULL) | ||
399 | return -EINVAL; | ||
400 | name_len = strlen(name); | ||
401 | if (name_len > 255 || value_len > sb->s_blocksize) | ||
402 | return -ERANGE; | ||
403 | down_write(&EXT2_I(inode)->xattr_sem); | ||
404 | if (EXT2_I(inode)->i_file_acl) { | ||
405 | /* The inode already has an extended attribute block. */ | ||
406 | bh = sb_bread(sb, EXT2_I(inode)->i_file_acl); | ||
407 | error = -EIO; | ||
408 | if (!bh) | ||
409 | goto cleanup; | ||
410 | ea_bdebug(bh, "b_count=%d, refcount=%d", | ||
411 | atomic_read(&(bh->b_count)), | ||
412 | le32_to_cpu(HDR(bh)->h_refcount)); | ||
413 | header = HDR(bh); | ||
414 | end = bh->b_data + bh->b_size; | ||
415 | if (header->h_magic != cpu_to_le32(EXT2_XATTR_MAGIC) || | ||
416 | header->h_blocks != cpu_to_le32(1)) { | ||
417 | bad_block: ext2_error(sb, "ext2_xattr_set", | ||
418 | "inode %ld: bad block %d", inode->i_ino, | ||
419 | EXT2_I(inode)->i_file_acl); | ||
420 | error = -EIO; | ||
421 | goto cleanup; | ||
422 | } | ||
423 | /* Find the named attribute. */ | ||
424 | here = FIRST_ENTRY(bh); | ||
425 | while (!IS_LAST_ENTRY(here)) { | ||
426 | struct ext2_xattr_entry *next = EXT2_XATTR_NEXT(here); | ||
427 | if ((char *)next >= end) | ||
428 | goto bad_block; | ||
429 | if (!here->e_value_block && here->e_value_size) { | ||
430 | size_t offs = le16_to_cpu(here->e_value_offs); | ||
431 | if (offs < min_offs) | ||
432 | min_offs = offs; | ||
433 | } | ||
434 | not_found = name_index - here->e_name_index; | ||
435 | if (!not_found) | ||
436 | not_found = name_len - here->e_name_len; | ||
437 | if (!not_found) | ||
438 | not_found = memcmp(name, here->e_name,name_len); | ||
439 | if (not_found <= 0) | ||
440 | break; | ||
441 | here = next; | ||
442 | } | ||
443 | last = here; | ||
444 | /* We still need to compute min_offs and last. */ | ||
445 | while (!IS_LAST_ENTRY(last)) { | ||
446 | struct ext2_xattr_entry *next = EXT2_XATTR_NEXT(last); | ||
447 | if ((char *)next >= end) | ||
448 | goto bad_block; | ||
449 | if (!last->e_value_block && last->e_value_size) { | ||
450 | size_t offs = le16_to_cpu(last->e_value_offs); | ||
451 | if (offs < min_offs) | ||
452 | min_offs = offs; | ||
453 | } | ||
454 | last = next; | ||
455 | } | ||
456 | |||
457 | /* Check whether we have enough space left. */ | ||
458 | free = min_offs - ((char*)last - (char*)header) - sizeof(__u32); | ||
459 | } else { | ||
460 | /* We will use a new extended attribute block. */ | ||
461 | free = sb->s_blocksize - | ||
462 | sizeof(struct ext2_xattr_header) - sizeof(__u32); | ||
463 | here = last = NULL; /* avoid gcc uninitialized warning. */ | ||
464 | } | ||
465 | |||
466 | if (not_found) { | ||
467 | /* Request to remove a nonexistent attribute? */ | ||
468 | error = -ENODATA; | ||
469 | if (flags & XATTR_REPLACE) | ||
470 | goto cleanup; | ||
471 | error = 0; | ||
472 | if (value == NULL) | ||
473 | goto cleanup; | ||
474 | } else { | ||
475 | /* Request to create an existing attribute? */ | ||
476 | error = -EEXIST; | ||
477 | if (flags & XATTR_CREATE) | ||
478 | goto cleanup; | ||
479 | if (!here->e_value_block && here->e_value_size) { | ||
480 | size_t size = le32_to_cpu(here->e_value_size); | ||
481 | |||
482 | if (le16_to_cpu(here->e_value_offs) + size > | ||
483 | sb->s_blocksize || size > sb->s_blocksize) | ||
484 | goto bad_block; | ||
485 | free += EXT2_XATTR_SIZE(size); | ||
486 | } | ||
487 | free += EXT2_XATTR_LEN(name_len); | ||
488 | } | ||
489 | error = -ENOSPC; | ||
490 | if (free < EXT2_XATTR_LEN(name_len) + EXT2_XATTR_SIZE(value_len)) | ||
491 | goto cleanup; | ||
492 | |||
493 | /* Here we know that we can set the new attribute. */ | ||
494 | |||
495 | if (header) { | ||
496 | struct mb_cache_entry *ce; | ||
497 | |||
498 | /* assert(header == HDR(bh)); */ | ||
499 | ce = mb_cache_entry_get(ext2_xattr_cache, bh->b_bdev, | ||
500 | bh->b_blocknr); | ||
501 | lock_buffer(bh); | ||
502 | if (header->h_refcount == cpu_to_le32(1)) { | ||
503 | ea_bdebug(bh, "modifying in-place"); | ||
504 | if (ce) | ||
505 | mb_cache_entry_free(ce); | ||
506 | /* keep the buffer locked while modifying it. */ | ||
507 | } else { | ||
508 | int offset; | ||
509 | |||
510 | if (ce) | ||
511 | mb_cache_entry_release(ce); | ||
512 | unlock_buffer(bh); | ||
513 | ea_bdebug(bh, "cloning"); | ||
514 | header = kmalloc(bh->b_size, GFP_KERNEL); | ||
515 | error = -ENOMEM; | ||
516 | if (header == NULL) | ||
517 | goto cleanup; | ||
518 | memcpy(header, HDR(bh), bh->b_size); | ||
519 | header->h_refcount = cpu_to_le32(1); | ||
520 | |||
521 | offset = (char *)here - bh->b_data; | ||
522 | here = ENTRY((char *)header + offset); | ||
523 | offset = (char *)last - bh->b_data; | ||
524 | last = ENTRY((char *)header + offset); | ||
525 | } | ||
526 | } else { | ||
527 | /* Allocate a buffer where we construct the new block. */ | ||
528 | header = kmalloc(sb->s_blocksize, GFP_KERNEL); | ||
529 | error = -ENOMEM; | ||
530 | if (header == NULL) | ||
531 | goto cleanup; | ||
532 | memset(header, 0, sb->s_blocksize); | ||
533 | end = (char *)header + sb->s_blocksize; | ||
534 | header->h_magic = cpu_to_le32(EXT2_XATTR_MAGIC); | ||
535 | header->h_blocks = header->h_refcount = cpu_to_le32(1); | ||
536 | last = here = ENTRY(header+1); | ||
537 | } | ||
538 | |||
539 | /* Iff we are modifying the block in-place, bh is locked here. */ | ||
540 | |||
541 | if (not_found) { | ||
542 | /* Insert the new name. */ | ||
543 | size_t size = EXT2_XATTR_LEN(name_len); | ||
544 | size_t rest = (char *)last - (char *)here; | ||
545 | memmove((char *)here + size, here, rest); | ||
546 | memset(here, 0, size); | ||
547 | here->e_name_index = name_index; | ||
548 | here->e_name_len = name_len; | ||
549 | memcpy(here->e_name, name, name_len); | ||
550 | } else { | ||
551 | if (!here->e_value_block && here->e_value_size) { | ||
552 | char *first_val = (char *)header + min_offs; | ||
553 | size_t offs = le16_to_cpu(here->e_value_offs); | ||
554 | char *val = (char *)header + offs; | ||
555 | size_t size = EXT2_XATTR_SIZE( | ||
556 | le32_to_cpu(here->e_value_size)); | ||
557 | |||
558 | if (size == EXT2_XATTR_SIZE(value_len)) { | ||
559 | /* The old and the new value have the same | ||
560 | size. Just replace. */ | ||
561 | here->e_value_size = cpu_to_le32(value_len); | ||
562 | memset(val + size - EXT2_XATTR_PAD, 0, | ||
563 | EXT2_XATTR_PAD); /* Clear pad bytes. */ | ||
564 | memcpy(val, value, value_len); | ||
565 | goto skip_replace; | ||
566 | } | ||
567 | |||
568 | /* Remove the old value. */ | ||
569 | memmove(first_val + size, first_val, val - first_val); | ||
570 | memset(first_val, 0, size); | ||
571 | here->e_value_offs = 0; | ||
572 | min_offs += size; | ||
573 | |||
574 | /* Adjust all value offsets. */ | ||
575 | last = ENTRY(header+1); | ||
576 | while (!IS_LAST_ENTRY(last)) { | ||
577 | size_t o = le16_to_cpu(last->e_value_offs); | ||
578 | if (!last->e_value_block && o < offs) | ||
579 | last->e_value_offs = | ||
580 | cpu_to_le16(o + size); | ||
581 | last = EXT2_XATTR_NEXT(last); | ||
582 | } | ||
583 | } | ||
584 | if (value == NULL) { | ||
585 | /* Remove the old name. */ | ||
586 | size_t size = EXT2_XATTR_LEN(name_len); | ||
587 | last = ENTRY((char *)last - size); | ||
588 | memmove(here, (char*)here + size, | ||
589 | (char*)last - (char*)here); | ||
590 | memset(last, 0, size); | ||
591 | } | ||
592 | } | ||
593 | |||
594 | if (value != NULL) { | ||
595 | /* Insert the new value. */ | ||
596 | here->e_value_size = cpu_to_le32(value_len); | ||
597 | if (value_len) { | ||
598 | size_t size = EXT2_XATTR_SIZE(value_len); | ||
599 | char *val = (char *)header + min_offs - size; | ||
600 | here->e_value_offs = | ||
601 | cpu_to_le16((char *)val - (char *)header); | ||
602 | memset(val + size - EXT2_XATTR_PAD, 0, | ||
603 | EXT2_XATTR_PAD); /* Clear the pad bytes. */ | ||
604 | memcpy(val, value, value_len); | ||
605 | } | ||
606 | } | ||
607 | |||
608 | skip_replace: | ||
609 | if (IS_LAST_ENTRY(ENTRY(header+1))) { | ||
610 | /* This block is now empty. */ | ||
611 | if (bh && header == HDR(bh)) | ||
612 | unlock_buffer(bh); /* we were modifying in-place. */ | ||
613 | error = ext2_xattr_set2(inode, bh, NULL); | ||
614 | } else { | ||
615 | ext2_xattr_rehash(header, here); | ||
616 | if (bh && header == HDR(bh)) | ||
617 | unlock_buffer(bh); /* we were modifying in-place. */ | ||
618 | error = ext2_xattr_set2(inode, bh, header); | ||
619 | } | ||
620 | |||
621 | cleanup: | ||
622 | brelse(bh); | ||
623 | if (!(bh && header == HDR(bh))) | ||
624 | kfree(header); | ||
625 | up_write(&EXT2_I(inode)->xattr_sem); | ||
626 | |||
627 | return error; | ||
628 | } | ||
629 | |||
630 | /* | ||
631 | * Second half of ext2_xattr_set(): Update the file system. | ||
632 | */ | ||
633 | static int | ||
634 | ext2_xattr_set2(struct inode *inode, struct buffer_head *old_bh, | ||
635 | struct ext2_xattr_header *header) | ||
636 | { | ||
637 | struct super_block *sb = inode->i_sb; | ||
638 | struct buffer_head *new_bh = NULL; | ||
639 | int error; | ||
640 | |||
641 | if (header) { | ||
642 | new_bh = ext2_xattr_cache_find(inode, header); | ||
643 | if (new_bh) { | ||
644 | /* We found an identical block in the cache. */ | ||
645 | if (new_bh == old_bh) { | ||
646 | ea_bdebug(new_bh, "keeping this block"); | ||
647 | } else { | ||
648 | /* The old block is released after updating | ||
649 | the inode. */ | ||
650 | ea_bdebug(new_bh, "reusing block"); | ||
651 | |||
652 | error = -EDQUOT; | ||
653 | if (DQUOT_ALLOC_BLOCK(inode, 1)) { | ||
654 | unlock_buffer(new_bh); | ||
655 | goto cleanup; | ||
656 | } | ||
657 | HDR(new_bh)->h_refcount = cpu_to_le32(1 + | ||
658 | le32_to_cpu(HDR(new_bh)->h_refcount)); | ||
659 | ea_bdebug(new_bh, "refcount now=%d", | ||
660 | le32_to_cpu(HDR(new_bh)->h_refcount)); | ||
661 | } | ||
662 | unlock_buffer(new_bh); | ||
663 | } else if (old_bh && header == HDR(old_bh)) { | ||
664 | /* Keep this block. No need to lock the block as we | ||
665 | don't need to change the reference count. */ | ||
666 | new_bh = old_bh; | ||
667 | get_bh(new_bh); | ||
668 | ext2_xattr_cache_insert(new_bh); | ||
669 | } else { | ||
670 | /* We need to allocate a new block */ | ||
671 | int goal = le32_to_cpu(EXT2_SB(sb)->s_es-> | ||
672 | s_first_data_block) + | ||
673 | EXT2_I(inode)->i_block_group * | ||
674 | EXT2_BLOCKS_PER_GROUP(sb); | ||
675 | int block = ext2_new_block(inode, goal, | ||
676 | NULL, NULL, &error); | ||
677 | if (error) | ||
678 | goto cleanup; | ||
679 | ea_idebug(inode, "creating block %d", block); | ||
680 | |||
681 | new_bh = sb_getblk(sb, block); | ||
682 | if (!new_bh) { | ||
683 | ext2_free_blocks(inode, block, 1); | ||
684 | error = -EIO; | ||
685 | goto cleanup; | ||
686 | } | ||
687 | lock_buffer(new_bh); | ||
688 | memcpy(new_bh->b_data, header, new_bh->b_size); | ||
689 | set_buffer_uptodate(new_bh); | ||
690 | unlock_buffer(new_bh); | ||
691 | ext2_xattr_cache_insert(new_bh); | ||
692 | |||
693 | ext2_xattr_update_super_block(sb); | ||
694 | } | ||
695 | mark_buffer_dirty(new_bh); | ||
696 | if (IS_SYNC(inode)) { | ||
697 | sync_dirty_buffer(new_bh); | ||
698 | error = -EIO; | ||
699 | if (buffer_req(new_bh) && !buffer_uptodate(new_bh)) | ||
700 | goto cleanup; | ||
701 | } | ||
702 | } | ||
703 | |||
704 | /* Update the inode. */ | ||
705 | EXT2_I(inode)->i_file_acl = new_bh ? new_bh->b_blocknr : 0; | ||
706 | inode->i_ctime = CURRENT_TIME_SEC; | ||
707 | if (IS_SYNC(inode)) { | ||
708 | error = ext2_sync_inode (inode); | ||
709 | /* In case sync failed due to ENOSPC the inode was actually | ||
710 | * written (only some dirty data were not) so we just proceed | ||
711 | * as if nothing happened and cleanup the unused block */ | ||
712 | if (error && error != -ENOSPC) { | ||
713 | if (new_bh && new_bh != old_bh) | ||
714 | DQUOT_FREE_BLOCK(inode, 1); | ||
715 | goto cleanup; | ||
716 | } | ||
717 | } else | ||
718 | mark_inode_dirty(inode); | ||
719 | |||
720 | error = 0; | ||
721 | if (old_bh && old_bh != new_bh) { | ||
722 | struct mb_cache_entry *ce; | ||
723 | |||
724 | /* | ||
725 | * If there was an old block and we are no longer using it, | ||
726 | * release the old block. | ||
727 | */ | ||
728 | ce = mb_cache_entry_get(ext2_xattr_cache, old_bh->b_bdev, | ||
729 | old_bh->b_blocknr); | ||
730 | lock_buffer(old_bh); | ||
731 | if (HDR(old_bh)->h_refcount == cpu_to_le32(1)) { | ||
732 | /* Free the old block. */ | ||
733 | if (ce) | ||
734 | mb_cache_entry_free(ce); | ||
735 | ea_bdebug(old_bh, "freeing"); | ||
736 | ext2_free_blocks(inode, old_bh->b_blocknr, 1); | ||
737 | /* We let our caller release old_bh, so we | ||
738 | * need to duplicate the buffer before. */ | ||
739 | get_bh(old_bh); | ||
740 | bforget(old_bh); | ||
741 | } else { | ||
742 | /* Decrement the refcount only. */ | ||
743 | HDR(old_bh)->h_refcount = cpu_to_le32( | ||
744 | le32_to_cpu(HDR(old_bh)->h_refcount) - 1); | ||
745 | if (ce) | ||
746 | mb_cache_entry_release(ce); | ||
747 | DQUOT_FREE_BLOCK(inode, 1); | ||
748 | mark_buffer_dirty(old_bh); | ||
749 | ea_bdebug(old_bh, "refcount now=%d", | ||
750 | le32_to_cpu(HDR(old_bh)->h_refcount)); | ||
751 | } | ||
752 | unlock_buffer(old_bh); | ||
753 | } | ||
754 | |||
755 | cleanup: | ||
756 | brelse(new_bh); | ||
757 | |||
758 | return error; | ||
759 | } | ||
760 | |||
761 | /* | ||
762 | * ext2_xattr_delete_inode() | ||
763 | * | ||
764 | * Free extended attribute resources associated with this inode. This | ||
765 | * is called immediately before an inode is freed. | ||
766 | */ | ||
767 | void | ||
768 | ext2_xattr_delete_inode(struct inode *inode) | ||
769 | { | ||
770 | struct buffer_head *bh = NULL; | ||
771 | struct mb_cache_entry *ce; | ||
772 | |||
773 | down_write(&EXT2_I(inode)->xattr_sem); | ||
774 | if (!EXT2_I(inode)->i_file_acl) | ||
775 | goto cleanup; | ||
776 | bh = sb_bread(inode->i_sb, EXT2_I(inode)->i_file_acl); | ||
777 | if (!bh) { | ||
778 | ext2_error(inode->i_sb, "ext2_xattr_delete_inode", | ||
779 | "inode %ld: block %d read error", inode->i_ino, | ||
780 | EXT2_I(inode)->i_file_acl); | ||
781 | goto cleanup; | ||
782 | } | ||
783 | ea_bdebug(bh, "b_count=%d", atomic_read(&(bh->b_count))); | ||
784 | if (HDR(bh)->h_magic != cpu_to_le32(EXT2_XATTR_MAGIC) || | ||
785 | HDR(bh)->h_blocks != cpu_to_le32(1)) { | ||
786 | ext2_error(inode->i_sb, "ext2_xattr_delete_inode", | ||
787 | "inode %ld: bad block %d", inode->i_ino, | ||
788 | EXT2_I(inode)->i_file_acl); | ||
789 | goto cleanup; | ||
790 | } | ||
791 | ce = mb_cache_entry_get(ext2_xattr_cache, bh->b_bdev, bh->b_blocknr); | ||
792 | lock_buffer(bh); | ||
793 | if (HDR(bh)->h_refcount == cpu_to_le32(1)) { | ||
794 | if (ce) | ||
795 | mb_cache_entry_free(ce); | ||
796 | ext2_free_blocks(inode, EXT2_I(inode)->i_file_acl, 1); | ||
797 | get_bh(bh); | ||
798 | bforget(bh); | ||
799 | } else { | ||
800 | HDR(bh)->h_refcount = cpu_to_le32( | ||
801 | le32_to_cpu(HDR(bh)->h_refcount) - 1); | ||
802 | if (ce) | ||
803 | mb_cache_entry_release(ce); | ||
804 | mark_buffer_dirty(bh); | ||
805 | if (IS_SYNC(inode)) | ||
806 | sync_dirty_buffer(bh); | ||
807 | DQUOT_FREE_BLOCK(inode, 1); | ||
808 | } | ||
809 | ea_bdebug(bh, "refcount now=%d", le32_to_cpu(HDR(bh)->h_refcount) - 1); | ||
810 | unlock_buffer(bh); | ||
811 | EXT2_I(inode)->i_file_acl = 0; | ||
812 | |||
813 | cleanup: | ||
814 | brelse(bh); | ||
815 | up_write(&EXT2_I(inode)->xattr_sem); | ||
816 | } | ||
817 | |||
818 | /* | ||
819 | * ext2_xattr_put_super() | ||
820 | * | ||
821 | * This is called when a file system is unmounted. | ||
822 | */ | ||
823 | void | ||
824 | ext2_xattr_put_super(struct super_block *sb) | ||
825 | { | ||
826 | mb_cache_shrink(ext2_xattr_cache, sb->s_bdev); | ||
827 | } | ||
828 | |||
829 | |||
830 | /* | ||
831 | * ext2_xattr_cache_insert() | ||
832 | * | ||
833 | * Create a new entry in the extended attribute cache, and insert | ||
834 | * it unless such an entry is already in the cache. | ||
835 | * | ||
836 | * Returns 0, or a negative error number on failure. | ||
837 | */ | ||
838 | static int | ||
839 | ext2_xattr_cache_insert(struct buffer_head *bh) | ||
840 | { | ||
841 | __u32 hash = le32_to_cpu(HDR(bh)->h_hash); | ||
842 | struct mb_cache_entry *ce; | ||
843 | int error; | ||
844 | |||
845 | ce = mb_cache_entry_alloc(ext2_xattr_cache); | ||
846 | if (!ce) | ||
847 | return -ENOMEM; | ||
848 | error = mb_cache_entry_insert(ce, bh->b_bdev, bh->b_blocknr, &hash); | ||
849 | if (error) { | ||
850 | mb_cache_entry_free(ce); | ||
851 | if (error == -EBUSY) { | ||
852 | ea_bdebug(bh, "already in cache (%d cache entries)", | ||
853 | atomic_read(&ext2_xattr_cache->c_entry_count)); | ||
854 | error = 0; | ||
855 | } | ||
856 | } else { | ||
857 | ea_bdebug(bh, "inserting [%x] (%d cache entries)", (int)hash, | ||
858 | atomic_read(&ext2_xattr_cache->c_entry_count)); | ||
859 | mb_cache_entry_release(ce); | ||
860 | } | ||
861 | return error; | ||
862 | } | ||
863 | |||
864 | /* | ||
865 | * ext2_xattr_cmp() | ||
866 | * | ||
867 | * Compare two extended attribute blocks for equality. | ||
868 | * | ||
869 | * Returns 0 if the blocks are equal, 1 if they differ, and | ||
870 | * a negative error number on errors. | ||
871 | */ | ||
872 | static int | ||
873 | ext2_xattr_cmp(struct ext2_xattr_header *header1, | ||
874 | struct ext2_xattr_header *header2) | ||
875 | { | ||
876 | struct ext2_xattr_entry *entry1, *entry2; | ||
877 | |||
878 | entry1 = ENTRY(header1+1); | ||
879 | entry2 = ENTRY(header2+1); | ||
880 | while (!IS_LAST_ENTRY(entry1)) { | ||
881 | if (IS_LAST_ENTRY(entry2)) | ||
882 | return 1; | ||
883 | if (entry1->e_hash != entry2->e_hash || | ||
884 | entry1->e_name_index != entry2->e_name_index || | ||
885 | entry1->e_name_len != entry2->e_name_len || | ||
886 | entry1->e_value_size != entry2->e_value_size || | ||
887 | memcmp(entry1->e_name, entry2->e_name, entry1->e_name_len)) | ||
888 | return 1; | ||
889 | if (entry1->e_value_block != 0 || entry2->e_value_block != 0) | ||
890 | return -EIO; | ||
891 | if (memcmp((char *)header1 + le16_to_cpu(entry1->e_value_offs), | ||
892 | (char *)header2 + le16_to_cpu(entry2->e_value_offs), | ||
893 | le32_to_cpu(entry1->e_value_size))) | ||
894 | return 1; | ||
895 | |||
896 | entry1 = EXT2_XATTR_NEXT(entry1); | ||
897 | entry2 = EXT2_XATTR_NEXT(entry2); | ||
898 | } | ||
899 | if (!IS_LAST_ENTRY(entry2)) | ||
900 | return 1; | ||
901 | return 0; | ||
902 | } | ||
903 | |||
904 | /* | ||
905 | * ext2_xattr_cache_find() | ||
906 | * | ||
907 | * Find an identical extended attribute block. | ||
908 | * | ||
909 | * Returns a locked buffer head to the block found, or NULL if such | ||
910 | * a block was not found or an error occurred. | ||
911 | */ | ||
912 | static struct buffer_head * | ||
913 | ext2_xattr_cache_find(struct inode *inode, struct ext2_xattr_header *header) | ||
914 | { | ||
915 | __u32 hash = le32_to_cpu(header->h_hash); | ||
916 | struct mb_cache_entry *ce; | ||
917 | |||
918 | if (!header->h_hash) | ||
919 | return NULL; /* never share */ | ||
920 | ea_idebug(inode, "looking for cached blocks [%x]", (int)hash); | ||
921 | again: | ||
922 | ce = mb_cache_entry_find_first(ext2_xattr_cache, 0, | ||
923 | inode->i_sb->s_bdev, hash); | ||
924 | while (ce) { | ||
925 | struct buffer_head *bh; | ||
926 | |||
927 | if (IS_ERR(ce)) { | ||
928 | if (PTR_ERR(ce) == -EAGAIN) | ||
929 | goto again; | ||
930 | break; | ||
931 | } | ||
932 | |||
933 | bh = sb_bread(inode->i_sb, ce->e_block); | ||
934 | if (!bh) { | ||
935 | ext2_error(inode->i_sb, "ext2_xattr_cache_find", | ||
936 | "inode %ld: block %ld read error", | ||
937 | inode->i_ino, (unsigned long) ce->e_block); | ||
938 | } else { | ||
939 | lock_buffer(bh); | ||
940 | if (le32_to_cpu(HDR(bh)->h_refcount) > | ||
941 | EXT2_XATTR_REFCOUNT_MAX) { | ||
942 | ea_idebug(inode, "block %ld refcount %d>%d", | ||
943 | (unsigned long) ce->e_block, | ||
944 | le32_to_cpu(HDR(bh)->h_refcount), | ||
945 | EXT2_XATTR_REFCOUNT_MAX); | ||
946 | } else if (!ext2_xattr_cmp(header, HDR(bh))) { | ||
947 | ea_bdebug(bh, "b_count=%d", | ||
948 | atomic_read(&(bh->b_count))); | ||
949 | mb_cache_entry_release(ce); | ||
950 | return bh; | ||
951 | } | ||
952 | unlock_buffer(bh); | ||
953 | brelse(bh); | ||
954 | } | ||
955 | ce = mb_cache_entry_find_next(ce, 0, inode->i_sb->s_bdev, hash); | ||
956 | } | ||
957 | return NULL; | ||
958 | } | ||
959 | |||
960 | #define NAME_HASH_SHIFT 5 | ||
961 | #define VALUE_HASH_SHIFT 16 | ||
962 | |||
963 | /* | ||
964 | * ext2_xattr_hash_entry() | ||
965 | * | ||
966 | * Compute the hash of an extended attribute. | ||
967 | */ | ||
968 | static inline void ext2_xattr_hash_entry(struct ext2_xattr_header *header, | ||
969 | struct ext2_xattr_entry *entry) | ||
970 | { | ||
971 | __u32 hash = 0; | ||
972 | char *name = entry->e_name; | ||
973 | int n; | ||
974 | |||
975 | for (n=0; n < entry->e_name_len; n++) { | ||
976 | hash = (hash << NAME_HASH_SHIFT) ^ | ||
977 | (hash >> (8*sizeof(hash) - NAME_HASH_SHIFT)) ^ | ||
978 | *name++; | ||
979 | } | ||
980 | |||
981 | if (entry->e_value_block == 0 && entry->e_value_size != 0) { | ||
982 | __le32 *value = (__le32 *)((char *)header + | ||
983 | le16_to_cpu(entry->e_value_offs)); | ||
984 | for (n = (le32_to_cpu(entry->e_value_size) + | ||
985 | EXT2_XATTR_ROUND) >> EXT2_XATTR_PAD_BITS; n; n--) { | ||
986 | hash = (hash << VALUE_HASH_SHIFT) ^ | ||
987 | (hash >> (8*sizeof(hash) - VALUE_HASH_SHIFT)) ^ | ||
988 | le32_to_cpu(*value++); | ||
989 | } | ||
990 | } | ||
991 | entry->e_hash = cpu_to_le32(hash); | ||
992 | } | ||
993 | |||
994 | #undef NAME_HASH_SHIFT | ||
995 | #undef VALUE_HASH_SHIFT | ||
996 | |||
997 | #define BLOCK_HASH_SHIFT 16 | ||
998 | |||
999 | /* | ||
1000 | * ext2_xattr_rehash() | ||
1001 | * | ||
1002 | * Re-compute the extended attribute hash value after an entry has changed. | ||
1003 | */ | ||
1004 | static void ext2_xattr_rehash(struct ext2_xattr_header *header, | ||
1005 | struct ext2_xattr_entry *entry) | ||
1006 | { | ||
1007 | struct ext2_xattr_entry *here; | ||
1008 | __u32 hash = 0; | ||
1009 | |||
1010 | ext2_xattr_hash_entry(header, entry); | ||
1011 | here = ENTRY(header+1); | ||
1012 | while (!IS_LAST_ENTRY(here)) { | ||
1013 | if (!here->e_hash) { | ||
1014 | /* Block is not shared if an entry's hash value == 0 */ | ||
1015 | hash = 0; | ||
1016 | break; | ||
1017 | } | ||
1018 | hash = (hash << BLOCK_HASH_SHIFT) ^ | ||
1019 | (hash >> (8*sizeof(hash) - BLOCK_HASH_SHIFT)) ^ | ||
1020 | le32_to_cpu(here->e_hash); | ||
1021 | here = EXT2_XATTR_NEXT(here); | ||
1022 | } | ||
1023 | header->h_hash = cpu_to_le32(hash); | ||
1024 | } | ||
1025 | |||
1026 | #undef BLOCK_HASH_SHIFT | ||
1027 | |||
1028 | int __init | ||
1029 | init_ext2_xattr(void) | ||
1030 | { | ||
1031 | ext2_xattr_cache = mb_cache_create("ext2_xattr", NULL, | ||
1032 | sizeof(struct mb_cache_entry) + | ||
1033 | sizeof(((struct mb_cache_entry *) 0)->e_indexes[0]), 1, 6); | ||
1034 | if (!ext2_xattr_cache) | ||
1035 | return -ENOMEM; | ||
1036 | return 0; | ||
1037 | } | ||
1038 | |||
1039 | void | ||
1040 | exit_ext2_xattr(void) | ||
1041 | { | ||
1042 | mb_cache_destroy(ext2_xattr_cache); | ||
1043 | } | ||