Commit | Line | Data |
---|---|---|
ac27a0ec | 1 | /* |
617ba13b | 2 | * linux/fs/ext4/xattr.c |
ac27a0ec DK |
3 | * |
4 | * Copyright (C) 2001-2003 Andreas Gruenbacher, <agruen@suse.de> | |
5 | * | |
6 | * Fix by Harrison Xing <harrison@mountainviewdata.com>. | |
617ba13b | 7 | * Ext4 code with a lot of help from Eric Jarman <ejarman@acm.org>. |
ac27a0ec DK |
8 | * Extended attributes for symlinks and special files added per |
9 | * suggestion of Luka Renko <luka.renko@hermes.si>. | |
10 | * xattr consolidation Copyright (c) 2004 James Morris <jmorris@redhat.com>, | |
11 | * Red Hat Inc. | |
12 | * ea-in-inode support by Alex Tomas <alex@clusterfs.com> aka bzzz | |
13 | * and Andreas Gruenbacher <agruen@suse.de>. | |
14 | */ | |
15 | ||
16 | /* | |
17 | * Extended attributes are stored directly in inodes (on file systems with | |
18 | * inodes bigger than 128 bytes) and on additional disk blocks. The i_file_acl | |
19 | * field contains the block number if an inode uses an additional block. All | |
20 | * attributes must fit in the inode and one additional block. Blocks that | |
21 | * contain the identical set of attributes may be shared among several inodes. | |
22 | * Identical blocks are detected by keeping a cache of blocks that have | |
23 | * recently been accessed. | |
24 | * | |
25 | * The attributes in inodes and on blocks have a different header; the entries | |
26 | * are stored in the same format: | |
27 | * | |
28 | * +------------------+ | |
29 | * | header | | |
30 | * | entry 1 | | | |
31 | * | entry 2 | | growing downwards | |
32 | * | entry 3 | v | |
33 | * | four null bytes | | |
34 | * | . . . | | |
35 | * | value 1 | ^ | |
36 | * | value 3 | | growing upwards | |
37 | * | value 2 | | | |
38 | * +------------------+ | |
39 | * | |
40 | * The header is followed by multiple entry descriptors. In disk blocks, the | |
41 | * entry descriptors are kept sorted. In inodes, they are unsorted. The | |
42 | * attribute values are aligned to the end of the block in no specific order. | |
43 | * | |
44 | * Locking strategy | |
45 | * ---------------- | |
617ba13b | 46 | * EXT4_I(inode)->i_file_acl is protected by EXT4_I(inode)->xattr_sem. |
ac27a0ec DK |
47 | * EA blocks are only changed if they are exclusive to an inode, so |
48 | * holding xattr_sem also means that nothing but the EA block's reference | |
49 | * count can change. Multiple writers to the same block are synchronized | |
50 | * by the buffer lock. | |
51 | */ | |
52 | ||
53 | #include <linux/init.h> | |
54 | #include <linux/fs.h> | |
55 | #include <linux/slab.h> | |
ac27a0ec DK |
56 | #include <linux/mbcache.h> |
57 | #include <linux/quotaops.h> | |
58 | #include <linux/rwsem.h> | |
3dcf5451 CH |
59 | #include "ext4_jbd2.h" |
60 | #include "ext4.h" | |
ac27a0ec DK |
61 | #include "xattr.h" |
62 | #include "acl.h" | |
63 | ||
617ba13b MC |
64 | #define BHDR(bh) ((struct ext4_xattr_header *)((bh)->b_data)) |
65 | #define ENTRY(ptr) ((struct ext4_xattr_entry *)(ptr)) | |
ac27a0ec DK |
66 | #define BFIRST(bh) ENTRY(BHDR(bh)+1) |
67 | #define IS_LAST_ENTRY(entry) (*(__u32 *)(entry) == 0) | |
68 | ||
617ba13b | 69 | #ifdef EXT4_XATTR_DEBUG |
ac27a0ec DK |
70 | # define ea_idebug(inode, f...) do { \ |
71 | printk(KERN_DEBUG "inode %s:%lu: ", \ | |
72 | inode->i_sb->s_id, inode->i_ino); \ | |
73 | printk(f); \ | |
74 | printk("\n"); \ | |
75 | } while (0) | |
76 | # define ea_bdebug(bh, f...) do { \ | |
77 | char b[BDEVNAME_SIZE]; \ | |
78 | printk(KERN_DEBUG "block %s:%lu: ", \ | |
79 | bdevname(bh->b_bdev, b), \ | |
80 | (unsigned long) bh->b_blocknr); \ | |
81 | printk(f); \ | |
82 | printk("\n"); \ | |
83 | } while (0) | |
84 | #else | |
ace36ad4 JP |
85 | # define ea_idebug(inode, fmt, ...) no_printk(fmt, ##__VA_ARGS__) |
86 | # define ea_bdebug(bh, fmt, ...) no_printk(fmt, ##__VA_ARGS__) | |
ac27a0ec DK |
87 | #endif |
88 | ||
617ba13b MC |
89 | static void ext4_xattr_cache_insert(struct buffer_head *); |
90 | static struct buffer_head *ext4_xattr_cache_find(struct inode *, | |
91 | struct ext4_xattr_header *, | |
ac27a0ec | 92 | struct mb_cache_entry **); |
617ba13b MC |
93 | static void ext4_xattr_rehash(struct ext4_xattr_header *, |
94 | struct ext4_xattr_entry *); | |
431547b3 | 95 | static int ext4_xattr_list(struct dentry *dentry, char *buffer, |
d3a95d47 | 96 | size_t buffer_size); |
ac27a0ec | 97 | |
617ba13b | 98 | static struct mb_cache *ext4_xattr_cache; |
ac27a0ec | 99 | |
11e27528 | 100 | static const struct xattr_handler *ext4_xattr_handler_map[] = { |
617ba13b | 101 | [EXT4_XATTR_INDEX_USER] = &ext4_xattr_user_handler, |
03010a33 | 102 | #ifdef CONFIG_EXT4_FS_POSIX_ACL |
617ba13b MC |
103 | [EXT4_XATTR_INDEX_POSIX_ACL_ACCESS] = &ext4_xattr_acl_access_handler, |
104 | [EXT4_XATTR_INDEX_POSIX_ACL_DEFAULT] = &ext4_xattr_acl_default_handler, | |
ac27a0ec | 105 | #endif |
617ba13b | 106 | [EXT4_XATTR_INDEX_TRUSTED] = &ext4_xattr_trusted_handler, |
03010a33 | 107 | #ifdef CONFIG_EXT4_FS_SECURITY |
617ba13b | 108 | [EXT4_XATTR_INDEX_SECURITY] = &ext4_xattr_security_handler, |
ac27a0ec DK |
109 | #endif |
110 | }; | |
111 | ||
11e27528 | 112 | const struct xattr_handler *ext4_xattr_handlers[] = { |
617ba13b MC |
113 | &ext4_xattr_user_handler, |
114 | &ext4_xattr_trusted_handler, | |
03010a33 | 115 | #ifdef CONFIG_EXT4_FS_POSIX_ACL |
617ba13b MC |
116 | &ext4_xattr_acl_access_handler, |
117 | &ext4_xattr_acl_default_handler, | |
ac27a0ec | 118 | #endif |
03010a33 | 119 | #ifdef CONFIG_EXT4_FS_SECURITY |
617ba13b | 120 | &ext4_xattr_security_handler, |
ac27a0ec DK |
121 | #endif |
122 | NULL | |
123 | }; | |
124 | ||
cc8e94fd DW |
125 | static __le32 ext4_xattr_block_csum(struct inode *inode, |
126 | sector_t block_nr, | |
127 | struct ext4_xattr_header *hdr) | |
128 | { | |
129 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); | |
cc8e94fd DW |
130 | __u32 csum, old; |
131 | ||
132 | old = hdr->h_checksum; | |
133 | hdr->h_checksum = 0; | |
41eb70dd TM |
134 | block_nr = cpu_to_le64(block_nr); |
135 | csum = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&block_nr, | |
136 | sizeof(block_nr)); | |
cc8e94fd DW |
137 | csum = ext4_chksum(sbi, csum, (__u8 *)hdr, |
138 | EXT4_BLOCK_SIZE(inode->i_sb)); | |
41eb70dd | 139 | |
cc8e94fd DW |
140 | hdr->h_checksum = old; |
141 | return cpu_to_le32(csum); | |
142 | } | |
143 | ||
144 | static int ext4_xattr_block_csum_verify(struct inode *inode, | |
145 | sector_t block_nr, | |
146 | struct ext4_xattr_header *hdr) | |
147 | { | |
148 | if (EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb, | |
149 | EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) && | |
150 | (hdr->h_checksum != ext4_xattr_block_csum(inode, block_nr, hdr))) | |
151 | return 0; | |
152 | return 1; | |
153 | } | |
154 | ||
155 | static void ext4_xattr_block_csum_set(struct inode *inode, | |
156 | sector_t block_nr, | |
157 | struct ext4_xattr_header *hdr) | |
158 | { | |
159 | if (!EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb, | |
160 | EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) | |
161 | return; | |
162 | ||
163 | hdr->h_checksum = ext4_xattr_block_csum(inode, block_nr, hdr); | |
164 | } | |
165 | ||
166 | static inline int ext4_handle_dirty_xattr_block(handle_t *handle, | |
167 | struct inode *inode, | |
168 | struct buffer_head *bh) | |
169 | { | |
170 | ext4_xattr_block_csum_set(inode, bh->b_blocknr, BHDR(bh)); | |
171 | return ext4_handle_dirty_metadata(handle, inode, bh); | |
172 | } | |
173 | ||
11e27528 | 174 | static inline const struct xattr_handler * |
617ba13b | 175 | ext4_xattr_handler(int name_index) |
ac27a0ec | 176 | { |
11e27528 | 177 | const struct xattr_handler *handler = NULL; |
ac27a0ec | 178 | |
617ba13b MC |
179 | if (name_index > 0 && name_index < ARRAY_SIZE(ext4_xattr_handler_map)) |
180 | handler = ext4_xattr_handler_map[name_index]; | |
ac27a0ec DK |
181 | return handler; |
182 | } | |
183 | ||
184 | /* | |
185 | * Inode operation listxattr() | |
186 | * | |
187 | * dentry->d_inode->i_mutex: don't care | |
188 | */ | |
189 | ssize_t | |
617ba13b | 190 | ext4_listxattr(struct dentry *dentry, char *buffer, size_t size) |
ac27a0ec | 191 | { |
431547b3 | 192 | return ext4_xattr_list(dentry, buffer, size); |
ac27a0ec DK |
193 | } |
194 | ||
195 | static int | |
617ba13b | 196 | ext4_xattr_check_names(struct ext4_xattr_entry *entry, void *end) |
ac27a0ec DK |
197 | { |
198 | while (!IS_LAST_ENTRY(entry)) { | |
617ba13b | 199 | struct ext4_xattr_entry *next = EXT4_XATTR_NEXT(entry); |
ac27a0ec DK |
200 | if ((void *)next >= end) |
201 | return -EIO; | |
202 | entry = next; | |
203 | } | |
204 | return 0; | |
205 | } | |
206 | ||
207 | static inline int | |
cc8e94fd | 208 | ext4_xattr_check_block(struct inode *inode, struct buffer_head *bh) |
ac27a0ec | 209 | { |
cc8e94fd DW |
210 | int error; |
211 | ||
212 | if (buffer_verified(bh)) | |
213 | return 0; | |
214 | ||
617ba13b | 215 | if (BHDR(bh)->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC) || |
ac27a0ec DK |
216 | BHDR(bh)->h_blocks != cpu_to_le32(1)) |
217 | return -EIO; | |
cc8e94fd DW |
218 | if (!ext4_xattr_block_csum_verify(inode, bh->b_blocknr, BHDR(bh))) |
219 | return -EIO; | |
220 | error = ext4_xattr_check_names(BFIRST(bh), bh->b_data + bh->b_size); | |
221 | if (!error) | |
222 | set_buffer_verified(bh); | |
223 | return error; | |
ac27a0ec DK |
224 | } |
225 | ||
226 | static inline int | |
617ba13b | 227 | ext4_xattr_check_entry(struct ext4_xattr_entry *entry, size_t size) |
ac27a0ec DK |
228 | { |
229 | size_t value_size = le32_to_cpu(entry->e_value_size); | |
230 | ||
231 | if (entry->e_value_block != 0 || value_size > size || | |
232 | le16_to_cpu(entry->e_value_offs) + value_size > size) | |
233 | return -EIO; | |
234 | return 0; | |
235 | } | |
236 | ||
237 | static int | |
617ba13b | 238 | ext4_xattr_find_entry(struct ext4_xattr_entry **pentry, int name_index, |
ac27a0ec DK |
239 | const char *name, size_t size, int sorted) |
240 | { | |
617ba13b | 241 | struct ext4_xattr_entry *entry; |
ac27a0ec DK |
242 | size_t name_len; |
243 | int cmp = 1; | |
244 | ||
245 | if (name == NULL) | |
246 | return -EINVAL; | |
247 | name_len = strlen(name); | |
248 | entry = *pentry; | |
617ba13b | 249 | for (; !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) { |
ac27a0ec DK |
250 | cmp = name_index - entry->e_name_index; |
251 | if (!cmp) | |
252 | cmp = name_len - entry->e_name_len; | |
253 | if (!cmp) | |
254 | cmp = memcmp(name, entry->e_name, name_len); | |
255 | if (cmp <= 0 && (sorted || cmp == 0)) | |
256 | break; | |
257 | } | |
258 | *pentry = entry; | |
617ba13b | 259 | if (!cmp && ext4_xattr_check_entry(entry, size)) |
ac27a0ec DK |
260 | return -EIO; |
261 | return cmp ? -ENODATA : 0; | |
262 | } | |
263 | ||
264 | static int | |
617ba13b | 265 | ext4_xattr_block_get(struct inode *inode, int name_index, const char *name, |
ac27a0ec DK |
266 | void *buffer, size_t buffer_size) |
267 | { | |
268 | struct buffer_head *bh = NULL; | |
617ba13b | 269 | struct ext4_xattr_entry *entry; |
ac27a0ec DK |
270 | size_t size; |
271 | int error; | |
272 | ||
273 | ea_idebug(inode, "name=%d.%s, buffer=%p, buffer_size=%ld", | |
274 | name_index, name, buffer, (long)buffer_size); | |
275 | ||
276 | error = -ENODATA; | |
617ba13b | 277 | if (!EXT4_I(inode)->i_file_acl) |
ac27a0ec | 278 | goto cleanup; |
ace36ad4 JP |
279 | ea_idebug(inode, "reading block %llu", |
280 | (unsigned long long)EXT4_I(inode)->i_file_acl); | |
617ba13b | 281 | bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl); |
ac27a0ec DK |
282 | if (!bh) |
283 | goto cleanup; | |
284 | ea_bdebug(bh, "b_count=%d, refcount=%d", | |
285 | atomic_read(&(bh->b_count)), le32_to_cpu(BHDR(bh)->h_refcount)); | |
cc8e94fd | 286 | if (ext4_xattr_check_block(inode, bh)) { |
12062ddd | 287 | bad_block: |
24676da4 TT |
288 | EXT4_ERROR_INODE(inode, "bad block %llu", |
289 | EXT4_I(inode)->i_file_acl); | |
ac27a0ec DK |
290 | error = -EIO; |
291 | goto cleanup; | |
292 | } | |
617ba13b | 293 | ext4_xattr_cache_insert(bh); |
ac27a0ec | 294 | entry = BFIRST(bh); |
617ba13b | 295 | error = ext4_xattr_find_entry(&entry, name_index, name, bh->b_size, 1); |
ac27a0ec DK |
296 | if (error == -EIO) |
297 | goto bad_block; | |
298 | if (error) | |
299 | goto cleanup; | |
300 | size = le32_to_cpu(entry->e_value_size); | |
301 | if (buffer) { | |
302 | error = -ERANGE; | |
303 | if (size > buffer_size) | |
304 | goto cleanup; | |
305 | memcpy(buffer, bh->b_data + le16_to_cpu(entry->e_value_offs), | |
306 | size); | |
307 | } | |
308 | error = size; | |
309 | ||
310 | cleanup: | |
311 | brelse(bh); | |
312 | return error; | |
313 | } | |
314 | ||
315 | static int | |
617ba13b | 316 | ext4_xattr_ibody_get(struct inode *inode, int name_index, const char *name, |
ac27a0ec DK |
317 | void *buffer, size_t buffer_size) |
318 | { | |
617ba13b MC |
319 | struct ext4_xattr_ibody_header *header; |
320 | struct ext4_xattr_entry *entry; | |
321 | struct ext4_inode *raw_inode; | |
322 | struct ext4_iloc iloc; | |
ac27a0ec DK |
323 | size_t size; |
324 | void *end; | |
325 | int error; | |
326 | ||
19f5fb7a | 327 | if (!ext4_test_inode_state(inode, EXT4_STATE_XATTR)) |
ac27a0ec | 328 | return -ENODATA; |
617ba13b | 329 | error = ext4_get_inode_loc(inode, &iloc); |
ac27a0ec DK |
330 | if (error) |
331 | return error; | |
617ba13b | 332 | raw_inode = ext4_raw_inode(&iloc); |
ac27a0ec DK |
333 | header = IHDR(inode, raw_inode); |
334 | entry = IFIRST(header); | |
617ba13b MC |
335 | end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; |
336 | error = ext4_xattr_check_names(entry, end); | |
ac27a0ec DK |
337 | if (error) |
338 | goto cleanup; | |
617ba13b | 339 | error = ext4_xattr_find_entry(&entry, name_index, name, |
ac27a0ec DK |
340 | end - (void *)entry, 0); |
341 | if (error) | |
342 | goto cleanup; | |
343 | size = le32_to_cpu(entry->e_value_size); | |
344 | if (buffer) { | |
345 | error = -ERANGE; | |
346 | if (size > buffer_size) | |
347 | goto cleanup; | |
348 | memcpy(buffer, (void *)IFIRST(header) + | |
349 | le16_to_cpu(entry->e_value_offs), size); | |
350 | } | |
351 | error = size; | |
352 | ||
353 | cleanup: | |
354 | brelse(iloc.bh); | |
355 | return error; | |
356 | } | |
357 | ||
358 | /* | |
617ba13b | 359 | * ext4_xattr_get() |
ac27a0ec DK |
360 | * |
361 | * Copy an extended attribute into the buffer | |
362 | * provided, or compute the buffer size required. | |
363 | * Buffer is NULL to compute the size of the buffer required. | |
364 | * | |
365 | * Returns a negative error number on failure, or the number of bytes | |
366 | * used / required on success. | |
367 | */ | |
368 | int | |
617ba13b | 369 | ext4_xattr_get(struct inode *inode, int name_index, const char *name, |
ac27a0ec DK |
370 | void *buffer, size_t buffer_size) |
371 | { | |
372 | int error; | |
373 | ||
617ba13b MC |
374 | down_read(&EXT4_I(inode)->xattr_sem); |
375 | error = ext4_xattr_ibody_get(inode, name_index, name, buffer, | |
ac27a0ec DK |
376 | buffer_size); |
377 | if (error == -ENODATA) | |
617ba13b | 378 | error = ext4_xattr_block_get(inode, name_index, name, buffer, |
ac27a0ec | 379 | buffer_size); |
617ba13b | 380 | up_read(&EXT4_I(inode)->xattr_sem); |
ac27a0ec DK |
381 | return error; |
382 | } | |
383 | ||
384 | static int | |
431547b3 | 385 | ext4_xattr_list_entries(struct dentry *dentry, struct ext4_xattr_entry *entry, |
ac27a0ec DK |
386 | char *buffer, size_t buffer_size) |
387 | { | |
388 | size_t rest = buffer_size; | |
389 | ||
617ba13b | 390 | for (; !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) { |
11e27528 | 391 | const struct xattr_handler *handler = |
617ba13b | 392 | ext4_xattr_handler(entry->e_name_index); |
ac27a0ec DK |
393 | |
394 | if (handler) { | |
431547b3 | 395 | size_t size = handler->list(dentry, buffer, rest, |
ac27a0ec | 396 | entry->e_name, |
431547b3 CH |
397 | entry->e_name_len, |
398 | handler->flags); | |
ac27a0ec DK |
399 | if (buffer) { |
400 | if (size > rest) | |
401 | return -ERANGE; | |
402 | buffer += size; | |
403 | } | |
404 | rest -= size; | |
405 | } | |
406 | } | |
407 | return buffer_size - rest; | |
408 | } | |
409 | ||
410 | static int | |
431547b3 | 411 | ext4_xattr_block_list(struct dentry *dentry, char *buffer, size_t buffer_size) |
ac27a0ec | 412 | { |
431547b3 | 413 | struct inode *inode = dentry->d_inode; |
ac27a0ec DK |
414 | struct buffer_head *bh = NULL; |
415 | int error; | |
416 | ||
417 | ea_idebug(inode, "buffer=%p, buffer_size=%ld", | |
418 | buffer, (long)buffer_size); | |
419 | ||
420 | error = 0; | |
617ba13b | 421 | if (!EXT4_I(inode)->i_file_acl) |
ac27a0ec | 422 | goto cleanup; |
ace36ad4 JP |
423 | ea_idebug(inode, "reading block %llu", |
424 | (unsigned long long)EXT4_I(inode)->i_file_acl); | |
617ba13b | 425 | bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl); |
ac27a0ec DK |
426 | error = -EIO; |
427 | if (!bh) | |
428 | goto cleanup; | |
429 | ea_bdebug(bh, "b_count=%d, refcount=%d", | |
430 | atomic_read(&(bh->b_count)), le32_to_cpu(BHDR(bh)->h_refcount)); | |
cc8e94fd | 431 | if (ext4_xattr_check_block(inode, bh)) { |
24676da4 TT |
432 | EXT4_ERROR_INODE(inode, "bad block %llu", |
433 | EXT4_I(inode)->i_file_acl); | |
ac27a0ec DK |
434 | error = -EIO; |
435 | goto cleanup; | |
436 | } | |
617ba13b | 437 | ext4_xattr_cache_insert(bh); |
431547b3 | 438 | error = ext4_xattr_list_entries(dentry, BFIRST(bh), buffer, buffer_size); |
ac27a0ec DK |
439 | |
440 | cleanup: | |
441 | brelse(bh); | |
442 | ||
443 | return error; | |
444 | } | |
445 | ||
446 | static int | |
431547b3 | 447 | ext4_xattr_ibody_list(struct dentry *dentry, char *buffer, size_t buffer_size) |
ac27a0ec | 448 | { |
431547b3 | 449 | struct inode *inode = dentry->d_inode; |
617ba13b MC |
450 | struct ext4_xattr_ibody_header *header; |
451 | struct ext4_inode *raw_inode; | |
452 | struct ext4_iloc iloc; | |
ac27a0ec DK |
453 | void *end; |
454 | int error; | |
455 | ||
19f5fb7a | 456 | if (!ext4_test_inode_state(inode, EXT4_STATE_XATTR)) |
ac27a0ec | 457 | return 0; |
617ba13b | 458 | error = ext4_get_inode_loc(inode, &iloc); |
ac27a0ec DK |
459 | if (error) |
460 | return error; | |
617ba13b | 461 | raw_inode = ext4_raw_inode(&iloc); |
ac27a0ec | 462 | header = IHDR(inode, raw_inode); |
617ba13b MC |
463 | end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; |
464 | error = ext4_xattr_check_names(IFIRST(header), end); | |
ac27a0ec DK |
465 | if (error) |
466 | goto cleanup; | |
431547b3 | 467 | error = ext4_xattr_list_entries(dentry, IFIRST(header), |
ac27a0ec DK |
468 | buffer, buffer_size); |
469 | ||
470 | cleanup: | |
471 | brelse(iloc.bh); | |
472 | return error; | |
473 | } | |
474 | ||
475 | /* | |
617ba13b | 476 | * ext4_xattr_list() |
ac27a0ec DK |
477 | * |
478 | * Copy a list of attribute names into the buffer | |
479 | * provided, or compute the buffer size required. | |
480 | * Buffer is NULL to compute the size of the buffer required. | |
481 | * | |
482 | * Returns a negative error number on failure, or the number of bytes | |
483 | * used / required on success. | |
484 | */ | |
d3a95d47 | 485 | static int |
431547b3 | 486 | ext4_xattr_list(struct dentry *dentry, char *buffer, size_t buffer_size) |
ac27a0ec | 487 | { |
eaeef867 | 488 | int ret, ret2; |
ac27a0ec | 489 | |
431547b3 | 490 | down_read(&EXT4_I(dentry->d_inode)->xattr_sem); |
eaeef867 TT |
491 | ret = ret2 = ext4_xattr_ibody_list(dentry, buffer, buffer_size); |
492 | if (ret < 0) | |
493 | goto errout; | |
494 | if (buffer) { | |
495 | buffer += ret; | |
496 | buffer_size -= ret; | |
ac27a0ec | 497 | } |
eaeef867 TT |
498 | ret = ext4_xattr_block_list(dentry, buffer, buffer_size); |
499 | if (ret < 0) | |
500 | goto errout; | |
501 | ret += ret2; | |
502 | errout: | |
431547b3 | 503 | up_read(&EXT4_I(dentry->d_inode)->xattr_sem); |
eaeef867 | 504 | return ret; |
ac27a0ec DK |
505 | } |
506 | ||
507 | /* | |
617ba13b | 508 | * If the EXT4_FEATURE_COMPAT_EXT_ATTR feature of this file system is |
ac27a0ec DK |
509 | * not set, set it. |
510 | */ | |
617ba13b | 511 | static void ext4_xattr_update_super_block(handle_t *handle, |
ac27a0ec DK |
512 | struct super_block *sb) |
513 | { | |
617ba13b | 514 | if (EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_EXT_ATTR)) |
ac27a0ec DK |
515 | return; |
516 | ||
617ba13b | 517 | if (ext4_journal_get_write_access(handle, EXT4_SB(sb)->s_sbh) == 0) { |
ed2908f3 | 518 | EXT4_SET_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_EXT_ATTR); |
a0375156 | 519 | ext4_handle_dirty_super(handle, sb); |
ac27a0ec | 520 | } |
ac27a0ec DK |
521 | } |
522 | ||
523 | /* | |
524 | * Release the xattr block BH: If the reference count is > 1, decrement | |
525 | * it; otherwise free the block. | |
526 | */ | |
527 | static void | |
617ba13b | 528 | ext4_xattr_release_block(handle_t *handle, struct inode *inode, |
ac27a0ec DK |
529 | struct buffer_head *bh) |
530 | { | |
531 | struct mb_cache_entry *ce = NULL; | |
8a2bfdcb | 532 | int error = 0; |
ac27a0ec | 533 | |
617ba13b | 534 | ce = mb_cache_entry_get(ext4_xattr_cache, bh->b_bdev, bh->b_blocknr); |
8a2bfdcb MC |
535 | error = ext4_journal_get_write_access(handle, bh); |
536 | if (error) | |
537 | goto out; | |
538 | ||
539 | lock_buffer(bh); | |
ac27a0ec DK |
540 | if (BHDR(bh)->h_refcount == cpu_to_le32(1)) { |
541 | ea_bdebug(bh, "refcount now=0; freeing"); | |
542 | if (ce) | |
543 | mb_cache_entry_free(ce); | |
ac27a0ec | 544 | get_bh(bh); |
e6362609 TT |
545 | ext4_free_blocks(handle, inode, bh, 0, 1, |
546 | EXT4_FREE_BLOCKS_METADATA | | |
547 | EXT4_FREE_BLOCKS_FORGET); | |
c1bb05a6 | 548 | unlock_buffer(bh); |
ac27a0ec | 549 | } else { |
e8546d06 | 550 | le32_add_cpu(&BHDR(bh)->h_refcount, -1); |
c1bb05a6 ES |
551 | if (ce) |
552 | mb_cache_entry_release(ce); | |
553 | unlock_buffer(bh); | |
cc8e94fd | 554 | error = ext4_handle_dirty_xattr_block(handle, inode, bh); |
8a2bfdcb | 555 | if (IS_SYNC(inode)) |
0390131b | 556 | ext4_handle_sync(handle); |
5dd4056d | 557 | dquot_free_block(inode, 1); |
8a2bfdcb MC |
558 | ea_bdebug(bh, "refcount now=%d; releasing", |
559 | le32_to_cpu(BHDR(bh)->h_refcount)); | |
ac27a0ec | 560 | } |
8a2bfdcb MC |
561 | out: |
562 | ext4_std_error(inode->i_sb, error); | |
563 | return; | |
ac27a0ec DK |
564 | } |
565 | ||
6dd4ee7c KS |
566 | /* |
567 | * Find the available free space for EAs. This also returns the total number of | |
568 | * bytes used by EA entries. | |
569 | */ | |
570 | static size_t ext4_xattr_free_space(struct ext4_xattr_entry *last, | |
571 | size_t *min_offs, void *base, int *total) | |
572 | { | |
573 | for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) { | |
574 | *total += EXT4_XATTR_LEN(last->e_name_len); | |
575 | if (!last->e_value_block && last->e_value_size) { | |
576 | size_t offs = le16_to_cpu(last->e_value_offs); | |
577 | if (offs < *min_offs) | |
578 | *min_offs = offs; | |
579 | } | |
580 | } | |
581 | return (*min_offs - ((void *)last - base) - sizeof(__u32)); | |
582 | } | |
583 | ||
617ba13b | 584 | struct ext4_xattr_info { |
ac27a0ec DK |
585 | int name_index; |
586 | const char *name; | |
587 | const void *value; | |
588 | size_t value_len; | |
589 | }; | |
590 | ||
617ba13b MC |
591 | struct ext4_xattr_search { |
592 | struct ext4_xattr_entry *first; | |
ac27a0ec DK |
593 | void *base; |
594 | void *end; | |
617ba13b | 595 | struct ext4_xattr_entry *here; |
ac27a0ec DK |
596 | int not_found; |
597 | }; | |
598 | ||
599 | static int | |
617ba13b | 600 | ext4_xattr_set_entry(struct ext4_xattr_info *i, struct ext4_xattr_search *s) |
ac27a0ec | 601 | { |
617ba13b | 602 | struct ext4_xattr_entry *last; |
ac27a0ec DK |
603 | size_t free, min_offs = s->end - s->base, name_len = strlen(i->name); |
604 | ||
605 | /* Compute min_offs and last. */ | |
606 | last = s->first; | |
617ba13b | 607 | for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) { |
ac27a0ec DK |
608 | if (!last->e_value_block && last->e_value_size) { |
609 | size_t offs = le16_to_cpu(last->e_value_offs); | |
610 | if (offs < min_offs) | |
611 | min_offs = offs; | |
612 | } | |
613 | } | |
614 | free = min_offs - ((void *)last - s->base) - sizeof(__u32); | |
615 | if (!s->not_found) { | |
616 | if (!s->here->e_value_block && s->here->e_value_size) { | |
617 | size_t size = le32_to_cpu(s->here->e_value_size); | |
617ba13b | 618 | free += EXT4_XATTR_SIZE(size); |
ac27a0ec | 619 | } |
617ba13b | 620 | free += EXT4_XATTR_LEN(name_len); |
ac27a0ec DK |
621 | } |
622 | if (i->value) { | |
617ba13b MC |
623 | if (free < EXT4_XATTR_SIZE(i->value_len) || |
624 | free < EXT4_XATTR_LEN(name_len) + | |
625 | EXT4_XATTR_SIZE(i->value_len)) | |
ac27a0ec DK |
626 | return -ENOSPC; |
627 | } | |
628 | ||
629 | if (i->value && s->not_found) { | |
630 | /* Insert the new name. */ | |
617ba13b | 631 | size_t size = EXT4_XATTR_LEN(name_len); |
ac27a0ec DK |
632 | size_t rest = (void *)last - (void *)s->here + sizeof(__u32); |
633 | memmove((void *)s->here + size, s->here, rest); | |
634 | memset(s->here, 0, size); | |
635 | s->here->e_name_index = i->name_index; | |
636 | s->here->e_name_len = name_len; | |
637 | memcpy(s->here->e_name, i->name, name_len); | |
638 | } else { | |
639 | if (!s->here->e_value_block && s->here->e_value_size) { | |
640 | void *first_val = s->base + min_offs; | |
641 | size_t offs = le16_to_cpu(s->here->e_value_offs); | |
642 | void *val = s->base + offs; | |
617ba13b | 643 | size_t size = EXT4_XATTR_SIZE( |
ac27a0ec DK |
644 | le32_to_cpu(s->here->e_value_size)); |
645 | ||
617ba13b | 646 | if (i->value && size == EXT4_XATTR_SIZE(i->value_len)) { |
ac27a0ec DK |
647 | /* The old and the new value have the same |
648 | size. Just replace. */ | |
649 | s->here->e_value_size = | |
650 | cpu_to_le32(i->value_len); | |
617ba13b MC |
651 | memset(val + size - EXT4_XATTR_PAD, 0, |
652 | EXT4_XATTR_PAD); /* Clear pad bytes. */ | |
ac27a0ec DK |
653 | memcpy(val, i->value, i->value_len); |
654 | return 0; | |
655 | } | |
656 | ||
657 | /* Remove the old value. */ | |
658 | memmove(first_val + size, first_val, val - first_val); | |
659 | memset(first_val, 0, size); | |
660 | s->here->e_value_size = 0; | |
661 | s->here->e_value_offs = 0; | |
662 | min_offs += size; | |
663 | ||
664 | /* Adjust all value offsets. */ | |
665 | last = s->first; | |
666 | while (!IS_LAST_ENTRY(last)) { | |
667 | size_t o = le16_to_cpu(last->e_value_offs); | |
668 | if (!last->e_value_block && | |
669 | last->e_value_size && o < offs) | |
670 | last->e_value_offs = | |
671 | cpu_to_le16(o + size); | |
617ba13b | 672 | last = EXT4_XATTR_NEXT(last); |
ac27a0ec DK |
673 | } |
674 | } | |
675 | if (!i->value) { | |
676 | /* Remove the old name. */ | |
617ba13b | 677 | size_t size = EXT4_XATTR_LEN(name_len); |
ac27a0ec DK |
678 | last = ENTRY((void *)last - size); |
679 | memmove(s->here, (void *)s->here + size, | |
680 | (void *)last - (void *)s->here + sizeof(__u32)); | |
681 | memset(last, 0, size); | |
682 | } | |
683 | } | |
684 | ||
685 | if (i->value) { | |
686 | /* Insert the new value. */ | |
687 | s->here->e_value_size = cpu_to_le32(i->value_len); | |
688 | if (i->value_len) { | |
617ba13b | 689 | size_t size = EXT4_XATTR_SIZE(i->value_len); |
ac27a0ec DK |
690 | void *val = s->base + min_offs - size; |
691 | s->here->e_value_offs = cpu_to_le16(min_offs - size); | |
617ba13b MC |
692 | memset(val + size - EXT4_XATTR_PAD, 0, |
693 | EXT4_XATTR_PAD); /* Clear the pad bytes. */ | |
ac27a0ec DK |
694 | memcpy(val, i->value, i->value_len); |
695 | } | |
696 | } | |
697 | return 0; | |
698 | } | |
699 | ||
617ba13b MC |
700 | struct ext4_xattr_block_find { |
701 | struct ext4_xattr_search s; | |
ac27a0ec DK |
702 | struct buffer_head *bh; |
703 | }; | |
704 | ||
705 | static int | |
617ba13b MC |
706 | ext4_xattr_block_find(struct inode *inode, struct ext4_xattr_info *i, |
707 | struct ext4_xattr_block_find *bs) | |
ac27a0ec DK |
708 | { |
709 | struct super_block *sb = inode->i_sb; | |
710 | int error; | |
711 | ||
712 | ea_idebug(inode, "name=%d.%s, value=%p, value_len=%ld", | |
713 | i->name_index, i->name, i->value, (long)i->value_len); | |
714 | ||
617ba13b | 715 | if (EXT4_I(inode)->i_file_acl) { |
ac27a0ec | 716 | /* The inode already has an extended attribute block. */ |
617ba13b | 717 | bs->bh = sb_bread(sb, EXT4_I(inode)->i_file_acl); |
ac27a0ec DK |
718 | error = -EIO; |
719 | if (!bs->bh) | |
720 | goto cleanup; | |
721 | ea_bdebug(bs->bh, "b_count=%d, refcount=%d", | |
722 | atomic_read(&(bs->bh->b_count)), | |
723 | le32_to_cpu(BHDR(bs->bh)->h_refcount)); | |
cc8e94fd | 724 | if (ext4_xattr_check_block(inode, bs->bh)) { |
24676da4 TT |
725 | EXT4_ERROR_INODE(inode, "bad block %llu", |
726 | EXT4_I(inode)->i_file_acl); | |
ac27a0ec DK |
727 | error = -EIO; |
728 | goto cleanup; | |
729 | } | |
730 | /* Find the named attribute. */ | |
731 | bs->s.base = BHDR(bs->bh); | |
732 | bs->s.first = BFIRST(bs->bh); | |
733 | bs->s.end = bs->bh->b_data + bs->bh->b_size; | |
734 | bs->s.here = bs->s.first; | |
617ba13b | 735 | error = ext4_xattr_find_entry(&bs->s.here, i->name_index, |
ac27a0ec DK |
736 | i->name, bs->bh->b_size, 1); |
737 | if (error && error != -ENODATA) | |
738 | goto cleanup; | |
739 | bs->s.not_found = error; | |
740 | } | |
741 | error = 0; | |
742 | ||
743 | cleanup: | |
744 | return error; | |
745 | } | |
746 | ||
747 | static int | |
617ba13b MC |
748 | ext4_xattr_block_set(handle_t *handle, struct inode *inode, |
749 | struct ext4_xattr_info *i, | |
750 | struct ext4_xattr_block_find *bs) | |
ac27a0ec DK |
751 | { |
752 | struct super_block *sb = inode->i_sb; | |
753 | struct buffer_head *new_bh = NULL; | |
617ba13b | 754 | struct ext4_xattr_search *s = &bs->s; |
ac27a0ec | 755 | struct mb_cache_entry *ce = NULL; |
8a2bfdcb | 756 | int error = 0; |
ac27a0ec | 757 | |
617ba13b | 758 | #define header(x) ((struct ext4_xattr_header *)(x)) |
ac27a0ec DK |
759 | |
760 | if (i->value && i->value_len > sb->s_blocksize) | |
761 | return -ENOSPC; | |
762 | if (s->base) { | |
617ba13b | 763 | ce = mb_cache_entry_get(ext4_xattr_cache, bs->bh->b_bdev, |
ac27a0ec | 764 | bs->bh->b_blocknr); |
8a2bfdcb MC |
765 | error = ext4_journal_get_write_access(handle, bs->bh); |
766 | if (error) | |
767 | goto cleanup; | |
768 | lock_buffer(bs->bh); | |
769 | ||
ac27a0ec DK |
770 | if (header(s->base)->h_refcount == cpu_to_le32(1)) { |
771 | if (ce) { | |
772 | mb_cache_entry_free(ce); | |
773 | ce = NULL; | |
774 | } | |
775 | ea_bdebug(bs->bh, "modifying in-place"); | |
617ba13b | 776 | error = ext4_xattr_set_entry(i, s); |
ac27a0ec DK |
777 | if (!error) { |
778 | if (!IS_LAST_ENTRY(s->first)) | |
617ba13b | 779 | ext4_xattr_rehash(header(s->base), |
ac27a0ec | 780 | s->here); |
617ba13b | 781 | ext4_xattr_cache_insert(bs->bh); |
ac27a0ec DK |
782 | } |
783 | unlock_buffer(bs->bh); | |
784 | if (error == -EIO) | |
785 | goto bad_block; | |
786 | if (!error) | |
cc8e94fd DW |
787 | error = ext4_handle_dirty_xattr_block(handle, |
788 | inode, | |
789 | bs->bh); | |
ac27a0ec DK |
790 | if (error) |
791 | goto cleanup; | |
792 | goto inserted; | |
793 | } else { | |
794 | int offset = (char *)s->here - bs->bh->b_data; | |
795 | ||
8a2bfdcb | 796 | unlock_buffer(bs->bh); |
ac27a0ec DK |
797 | if (ce) { |
798 | mb_cache_entry_release(ce); | |
799 | ce = NULL; | |
800 | } | |
801 | ea_bdebug(bs->bh, "cloning"); | |
216553c4 | 802 | s->base = kmalloc(bs->bh->b_size, GFP_NOFS); |
ac27a0ec DK |
803 | error = -ENOMEM; |
804 | if (s->base == NULL) | |
805 | goto cleanup; | |
806 | memcpy(s->base, BHDR(bs->bh), bs->bh->b_size); | |
807 | s->first = ENTRY(header(s->base)+1); | |
808 | header(s->base)->h_refcount = cpu_to_le32(1); | |
809 | s->here = ENTRY(s->base + offset); | |
810 | s->end = s->base + bs->bh->b_size; | |
811 | } | |
812 | } else { | |
813 | /* Allocate a buffer where we construct the new block. */ | |
216553c4 | 814 | s->base = kzalloc(sb->s_blocksize, GFP_NOFS); |
ac27a0ec DK |
815 | /* assert(header == s->base) */ |
816 | error = -ENOMEM; | |
817 | if (s->base == NULL) | |
818 | goto cleanup; | |
617ba13b | 819 | header(s->base)->h_magic = cpu_to_le32(EXT4_XATTR_MAGIC); |
ac27a0ec DK |
820 | header(s->base)->h_blocks = cpu_to_le32(1); |
821 | header(s->base)->h_refcount = cpu_to_le32(1); | |
822 | s->first = ENTRY(header(s->base)+1); | |
823 | s->here = ENTRY(header(s->base)+1); | |
824 | s->end = s->base + sb->s_blocksize; | |
825 | } | |
826 | ||
617ba13b | 827 | error = ext4_xattr_set_entry(i, s); |
ac27a0ec DK |
828 | if (error == -EIO) |
829 | goto bad_block; | |
830 | if (error) | |
831 | goto cleanup; | |
832 | if (!IS_LAST_ENTRY(s->first)) | |
617ba13b | 833 | ext4_xattr_rehash(header(s->base), s->here); |
ac27a0ec DK |
834 | |
835 | inserted: | |
836 | if (!IS_LAST_ENTRY(s->first)) { | |
617ba13b | 837 | new_bh = ext4_xattr_cache_find(inode, header(s->base), &ce); |
ac27a0ec DK |
838 | if (new_bh) { |
839 | /* We found an identical block in the cache. */ | |
840 | if (new_bh == bs->bh) | |
841 | ea_bdebug(new_bh, "keeping"); | |
842 | else { | |
843 | /* The old block is released after updating | |
844 | the inode. */ | |
5dd4056d CH |
845 | error = dquot_alloc_block(inode, 1); |
846 | if (error) | |
ac27a0ec | 847 | goto cleanup; |
617ba13b | 848 | error = ext4_journal_get_write_access(handle, |
ac27a0ec DK |
849 | new_bh); |
850 | if (error) | |
851 | goto cleanup_dquot; | |
852 | lock_buffer(new_bh); | |
e8546d06 | 853 | le32_add_cpu(&BHDR(new_bh)->h_refcount, 1); |
ac27a0ec DK |
854 | ea_bdebug(new_bh, "reusing; refcount now=%d", |
855 | le32_to_cpu(BHDR(new_bh)->h_refcount)); | |
856 | unlock_buffer(new_bh); | |
cc8e94fd DW |
857 | error = ext4_handle_dirty_xattr_block(handle, |
858 | inode, | |
859 | new_bh); | |
ac27a0ec DK |
860 | if (error) |
861 | goto cleanup_dquot; | |
862 | } | |
863 | mb_cache_entry_release(ce); | |
864 | ce = NULL; | |
865 | } else if (bs->bh && s->base == bs->bh->b_data) { | |
866 | /* We were modifying this block in-place. */ | |
867 | ea_bdebug(bs->bh, "keeping this block"); | |
868 | new_bh = bs->bh; | |
869 | get_bh(new_bh); | |
870 | } else { | |
871 | /* We need to allocate a new block */ | |
fb0a387d ES |
872 | ext4_fsblk_t goal, block; |
873 | ||
874 | goal = ext4_group_first_block_no(sb, | |
d00a6d7b | 875 | EXT4_I(inode)->i_block_group); |
fb0a387d ES |
876 | |
877 | /* non-extent files can't have physical blocks past 2^32 */ | |
12e9b892 | 878 | if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) |
fb0a387d ES |
879 | goal = goal & EXT4_MAX_BLOCK_FILE_PHYS; |
880 | ||
6d6a4351 ES |
881 | /* |
882 | * take i_data_sem because we will test | |
883 | * i_delalloc_reserved_flag in ext4_mb_new_blocks | |
884 | */ | |
885 | down_read((&EXT4_I(inode)->i_data_sem)); | |
55f020db AH |
886 | block = ext4_new_meta_blocks(handle, inode, goal, 0, |
887 | NULL, &error); | |
6d6a4351 | 888 | up_read((&EXT4_I(inode)->i_data_sem)); |
ac27a0ec DK |
889 | if (error) |
890 | goto cleanup; | |
fb0a387d | 891 | |
12e9b892 | 892 | if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) |
fb0a387d ES |
893 | BUG_ON(block > EXT4_MAX_BLOCK_FILE_PHYS); |
894 | ||
ace36ad4 JP |
895 | ea_idebug(inode, "creating block %llu", |
896 | (unsigned long long)block); | |
ac27a0ec DK |
897 | |
898 | new_bh = sb_getblk(sb, block); | |
899 | if (!new_bh) { | |
900 | getblk_failed: | |
7dc57615 | 901 | ext4_free_blocks(handle, inode, NULL, block, 1, |
e6362609 | 902 | EXT4_FREE_BLOCKS_METADATA); |
ac27a0ec DK |
903 | error = -EIO; |
904 | goto cleanup; | |
905 | } | |
906 | lock_buffer(new_bh); | |
617ba13b | 907 | error = ext4_journal_get_create_access(handle, new_bh); |
ac27a0ec DK |
908 | if (error) { |
909 | unlock_buffer(new_bh); | |
910 | goto getblk_failed; | |
911 | } | |
912 | memcpy(new_bh->b_data, s->base, new_bh->b_size); | |
913 | set_buffer_uptodate(new_bh); | |
914 | unlock_buffer(new_bh); | |
617ba13b | 915 | ext4_xattr_cache_insert(new_bh); |
cc8e94fd DW |
916 | error = ext4_handle_dirty_xattr_block(handle, |
917 | inode, new_bh); | |
ac27a0ec DK |
918 | if (error) |
919 | goto cleanup; | |
920 | } | |
921 | } | |
922 | ||
923 | /* Update the inode. */ | |
617ba13b | 924 | EXT4_I(inode)->i_file_acl = new_bh ? new_bh->b_blocknr : 0; |
ac27a0ec DK |
925 | |
926 | /* Drop the previous xattr block. */ | |
927 | if (bs->bh && bs->bh != new_bh) | |
617ba13b | 928 | ext4_xattr_release_block(handle, inode, bs->bh); |
ac27a0ec DK |
929 | error = 0; |
930 | ||
931 | cleanup: | |
932 | if (ce) | |
933 | mb_cache_entry_release(ce); | |
934 | brelse(new_bh); | |
935 | if (!(bs->bh && s->base == bs->bh->b_data)) | |
936 | kfree(s->base); | |
937 | ||
938 | return error; | |
939 | ||
940 | cleanup_dquot: | |
5dd4056d | 941 | dquot_free_block(inode, 1); |
ac27a0ec DK |
942 | goto cleanup; |
943 | ||
944 | bad_block: | |
24676da4 TT |
945 | EXT4_ERROR_INODE(inode, "bad block %llu", |
946 | EXT4_I(inode)->i_file_acl); | |
ac27a0ec DK |
947 | goto cleanup; |
948 | ||
949 | #undef header | |
950 | } | |
951 | ||
617ba13b MC |
952 | struct ext4_xattr_ibody_find { |
953 | struct ext4_xattr_search s; | |
954 | struct ext4_iloc iloc; | |
ac27a0ec DK |
955 | }; |
956 | ||
957 | static int | |
617ba13b MC |
958 | ext4_xattr_ibody_find(struct inode *inode, struct ext4_xattr_info *i, |
959 | struct ext4_xattr_ibody_find *is) | |
ac27a0ec | 960 | { |
617ba13b MC |
961 | struct ext4_xattr_ibody_header *header; |
962 | struct ext4_inode *raw_inode; | |
ac27a0ec DK |
963 | int error; |
964 | ||
617ba13b | 965 | if (EXT4_I(inode)->i_extra_isize == 0) |
ac27a0ec | 966 | return 0; |
617ba13b | 967 | raw_inode = ext4_raw_inode(&is->iloc); |
ac27a0ec DK |
968 | header = IHDR(inode, raw_inode); |
969 | is->s.base = is->s.first = IFIRST(header); | |
970 | is->s.here = is->s.first; | |
617ba13b | 971 | is->s.end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; |
19f5fb7a | 972 | if (ext4_test_inode_state(inode, EXT4_STATE_XATTR)) { |
617ba13b | 973 | error = ext4_xattr_check_names(IFIRST(header), is->s.end); |
ac27a0ec DK |
974 | if (error) |
975 | return error; | |
976 | /* Find the named attribute. */ | |
617ba13b | 977 | error = ext4_xattr_find_entry(&is->s.here, i->name_index, |
ac27a0ec DK |
978 | i->name, is->s.end - |
979 | (void *)is->s.base, 0); | |
980 | if (error && error != -ENODATA) | |
981 | return error; | |
982 | is->s.not_found = error; | |
983 | } | |
984 | return 0; | |
985 | } | |
986 | ||
987 | static int | |
617ba13b MC |
988 | ext4_xattr_ibody_set(handle_t *handle, struct inode *inode, |
989 | struct ext4_xattr_info *i, | |
990 | struct ext4_xattr_ibody_find *is) | |
ac27a0ec | 991 | { |
617ba13b MC |
992 | struct ext4_xattr_ibody_header *header; |
993 | struct ext4_xattr_search *s = &is->s; | |
ac27a0ec DK |
994 | int error; |
995 | ||
617ba13b | 996 | if (EXT4_I(inode)->i_extra_isize == 0) |
ac27a0ec | 997 | return -ENOSPC; |
617ba13b | 998 | error = ext4_xattr_set_entry(i, s); |
ac27a0ec DK |
999 | if (error) |
1000 | return error; | |
617ba13b | 1001 | header = IHDR(inode, ext4_raw_inode(&is->iloc)); |
ac27a0ec | 1002 | if (!IS_LAST_ENTRY(s->first)) { |
617ba13b | 1003 | header->h_magic = cpu_to_le32(EXT4_XATTR_MAGIC); |
19f5fb7a | 1004 | ext4_set_inode_state(inode, EXT4_STATE_XATTR); |
ac27a0ec DK |
1005 | } else { |
1006 | header->h_magic = cpu_to_le32(0); | |
19f5fb7a | 1007 | ext4_clear_inode_state(inode, EXT4_STATE_XATTR); |
ac27a0ec DK |
1008 | } |
1009 | return 0; | |
1010 | } | |
1011 | ||
1012 | /* | |
617ba13b | 1013 | * ext4_xattr_set_handle() |
ac27a0ec | 1014 | * |
6e9510b0 | 1015 | * Create, replace or remove an extended attribute for this inode. Value |
ac27a0ec DK |
1016 | * is NULL to remove an existing extended attribute, and non-NULL to |
1017 | * either replace an existing extended attribute, or create a new extended | |
1018 | * attribute. The flags XATTR_REPLACE and XATTR_CREATE | |
1019 | * specify that an extended attribute must exist and must not exist | |
1020 | * previous to the call, respectively. | |
1021 | * | |
1022 | * Returns 0, or a negative error number on failure. | |
1023 | */ | |
1024 | int | |
617ba13b | 1025 | ext4_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index, |
ac27a0ec DK |
1026 | const char *name, const void *value, size_t value_len, |
1027 | int flags) | |
1028 | { | |
617ba13b | 1029 | struct ext4_xattr_info i = { |
ac27a0ec DK |
1030 | .name_index = name_index, |
1031 | .name = name, | |
1032 | .value = value, | |
1033 | .value_len = value_len, | |
1034 | ||
1035 | }; | |
617ba13b | 1036 | struct ext4_xattr_ibody_find is = { |
ac27a0ec DK |
1037 | .s = { .not_found = -ENODATA, }, |
1038 | }; | |
617ba13b | 1039 | struct ext4_xattr_block_find bs = { |
ac27a0ec DK |
1040 | .s = { .not_found = -ENODATA, }, |
1041 | }; | |
4d20c685 | 1042 | unsigned long no_expand; |
ac27a0ec DK |
1043 | int error; |
1044 | ||
1045 | if (!name) | |
1046 | return -EINVAL; | |
1047 | if (strlen(name) > 255) | |
1048 | return -ERANGE; | |
617ba13b | 1049 | down_write(&EXT4_I(inode)->xattr_sem); |
19f5fb7a TT |
1050 | no_expand = ext4_test_inode_state(inode, EXT4_STATE_NO_EXPAND); |
1051 | ext4_set_inode_state(inode, EXT4_STATE_NO_EXPAND); | |
4d20c685 | 1052 | |
66543617 | 1053 | error = ext4_reserve_inode_write(handle, inode, &is.iloc); |
86ebfd08 ES |
1054 | if (error) |
1055 | goto cleanup; | |
1056 | ||
19f5fb7a | 1057 | if (ext4_test_inode_state(inode, EXT4_STATE_NEW)) { |
617ba13b MC |
1058 | struct ext4_inode *raw_inode = ext4_raw_inode(&is.iloc); |
1059 | memset(raw_inode, 0, EXT4_SB(inode->i_sb)->s_inode_size); | |
19f5fb7a | 1060 | ext4_clear_inode_state(inode, EXT4_STATE_NEW); |
ac27a0ec DK |
1061 | } |
1062 | ||
617ba13b | 1063 | error = ext4_xattr_ibody_find(inode, &i, &is); |
ac27a0ec DK |
1064 | if (error) |
1065 | goto cleanup; | |
1066 | if (is.s.not_found) | |
617ba13b | 1067 | error = ext4_xattr_block_find(inode, &i, &bs); |
ac27a0ec DK |
1068 | if (error) |
1069 | goto cleanup; | |
1070 | if (is.s.not_found && bs.s.not_found) { | |
1071 | error = -ENODATA; | |
1072 | if (flags & XATTR_REPLACE) | |
1073 | goto cleanup; | |
1074 | error = 0; | |
1075 | if (!value) | |
1076 | goto cleanup; | |
1077 | } else { | |
1078 | error = -EEXIST; | |
1079 | if (flags & XATTR_CREATE) | |
1080 | goto cleanup; | |
1081 | } | |
ac27a0ec DK |
1082 | if (!value) { |
1083 | if (!is.s.not_found) | |
617ba13b | 1084 | error = ext4_xattr_ibody_set(handle, inode, &i, &is); |
ac27a0ec | 1085 | else if (!bs.s.not_found) |
617ba13b | 1086 | error = ext4_xattr_block_set(handle, inode, &i, &bs); |
ac27a0ec | 1087 | } else { |
617ba13b | 1088 | error = ext4_xattr_ibody_set(handle, inode, &i, &is); |
ac27a0ec DK |
1089 | if (!error && !bs.s.not_found) { |
1090 | i.value = NULL; | |
617ba13b | 1091 | error = ext4_xattr_block_set(handle, inode, &i, &bs); |
ac27a0ec | 1092 | } else if (error == -ENOSPC) { |
7e01c8e5 TY |
1093 | if (EXT4_I(inode)->i_file_acl && !bs.s.base) { |
1094 | error = ext4_xattr_block_find(inode, &i, &bs); | |
1095 | if (error) | |
1096 | goto cleanup; | |
1097 | } | |
617ba13b | 1098 | error = ext4_xattr_block_set(handle, inode, &i, &bs); |
ac27a0ec DK |
1099 | if (error) |
1100 | goto cleanup; | |
1101 | if (!is.s.not_found) { | |
1102 | i.value = NULL; | |
617ba13b | 1103 | error = ext4_xattr_ibody_set(handle, inode, &i, |
ac27a0ec DK |
1104 | &is); |
1105 | } | |
1106 | } | |
1107 | } | |
1108 | if (!error) { | |
617ba13b | 1109 | ext4_xattr_update_super_block(handle, inode->i_sb); |
ef7f3835 | 1110 | inode->i_ctime = ext4_current_time(inode); |
6dd4ee7c | 1111 | if (!value) |
19f5fb7a | 1112 | ext4_clear_inode_state(inode, EXT4_STATE_NO_EXPAND); |
617ba13b | 1113 | error = ext4_mark_iloc_dirty(handle, inode, &is.iloc); |
ac27a0ec | 1114 | /* |
617ba13b | 1115 | * The bh is consumed by ext4_mark_iloc_dirty, even with |
ac27a0ec DK |
1116 | * error != 0. |
1117 | */ | |
1118 | is.iloc.bh = NULL; | |
1119 | if (IS_SYNC(inode)) | |
0390131b | 1120 | ext4_handle_sync(handle); |
ac27a0ec DK |
1121 | } |
1122 | ||
1123 | cleanup: | |
1124 | brelse(is.iloc.bh); | |
1125 | brelse(bs.bh); | |
4d20c685 | 1126 | if (no_expand == 0) |
19f5fb7a | 1127 | ext4_clear_inode_state(inode, EXT4_STATE_NO_EXPAND); |
617ba13b | 1128 | up_write(&EXT4_I(inode)->xattr_sem); |
ac27a0ec DK |
1129 | return error; |
1130 | } | |
1131 | ||
1132 | /* | |
617ba13b | 1133 | * ext4_xattr_set() |
ac27a0ec | 1134 | * |
617ba13b | 1135 | * Like ext4_xattr_set_handle, but start from an inode. This extended |
ac27a0ec DK |
1136 | * attribute modification is a filesystem transaction by itself. |
1137 | * | |
1138 | * Returns 0, or a negative error number on failure. | |
1139 | */ | |
1140 | int | |
617ba13b | 1141 | ext4_xattr_set(struct inode *inode, int name_index, const char *name, |
ac27a0ec DK |
1142 | const void *value, size_t value_len, int flags) |
1143 | { | |
1144 | handle_t *handle; | |
1145 | int error, retries = 0; | |
1146 | ||
1147 | retry: | |
617ba13b | 1148 | handle = ext4_journal_start(inode, EXT4_DATA_TRANS_BLOCKS(inode->i_sb)); |
ac27a0ec DK |
1149 | if (IS_ERR(handle)) { |
1150 | error = PTR_ERR(handle); | |
1151 | } else { | |
1152 | int error2; | |
1153 | ||
617ba13b | 1154 | error = ext4_xattr_set_handle(handle, inode, name_index, name, |
ac27a0ec | 1155 | value, value_len, flags); |
617ba13b | 1156 | error2 = ext4_journal_stop(handle); |
ac27a0ec | 1157 | if (error == -ENOSPC && |
617ba13b | 1158 | ext4_should_retry_alloc(inode->i_sb, &retries)) |
ac27a0ec DK |
1159 | goto retry; |
1160 | if (error == 0) | |
1161 | error = error2; | |
1162 | } | |
1163 | ||
1164 | return error; | |
1165 | } | |
1166 | ||
6dd4ee7c KS |
1167 | /* |
1168 | * Shift the EA entries in the inode to create space for the increased | |
1169 | * i_extra_isize. | |
1170 | */ | |
1171 | static void ext4_xattr_shift_entries(struct ext4_xattr_entry *entry, | |
1172 | int value_offs_shift, void *to, | |
1173 | void *from, size_t n, int blocksize) | |
1174 | { | |
1175 | struct ext4_xattr_entry *last = entry; | |
1176 | int new_offs; | |
1177 | ||
1178 | /* Adjust the value offsets of the entries */ | |
1179 | for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) { | |
1180 | if (!last->e_value_block && last->e_value_size) { | |
1181 | new_offs = le16_to_cpu(last->e_value_offs) + | |
1182 | value_offs_shift; | |
1183 | BUG_ON(new_offs + le32_to_cpu(last->e_value_size) | |
1184 | > blocksize); | |
1185 | last->e_value_offs = cpu_to_le16(new_offs); | |
1186 | } | |
1187 | } | |
1188 | /* Shift the entries by n bytes */ | |
1189 | memmove(to, from, n); | |
1190 | } | |
1191 | ||
1192 | /* | |
1193 | * Expand an inode by new_extra_isize bytes when EAs are present. | |
1194 | * Returns 0 on success or negative error number on failure. | |
1195 | */ | |
1196 | int ext4_expand_extra_isize_ea(struct inode *inode, int new_extra_isize, | |
1197 | struct ext4_inode *raw_inode, handle_t *handle) | |
1198 | { | |
1199 | struct ext4_xattr_ibody_header *header; | |
1200 | struct ext4_xattr_entry *entry, *last, *first; | |
1201 | struct buffer_head *bh = NULL; | |
1202 | struct ext4_xattr_ibody_find *is = NULL; | |
1203 | struct ext4_xattr_block_find *bs = NULL; | |
1204 | char *buffer = NULL, *b_entry_name = NULL; | |
1205 | size_t min_offs, free; | |
1206 | int total_ino, total_blk; | |
1207 | void *base, *start, *end; | |
1208 | int extra_isize = 0, error = 0, tried_min_extra_isize = 0; | |
ac39849d | 1209 | int s_min_extra_isize = le16_to_cpu(EXT4_SB(inode->i_sb)->s_es->s_min_extra_isize); |
6dd4ee7c KS |
1210 | |
1211 | down_write(&EXT4_I(inode)->xattr_sem); | |
1212 | retry: | |
1213 | if (EXT4_I(inode)->i_extra_isize >= new_extra_isize) { | |
1214 | up_write(&EXT4_I(inode)->xattr_sem); | |
1215 | return 0; | |
1216 | } | |
1217 | ||
1218 | header = IHDR(inode, raw_inode); | |
1219 | entry = IFIRST(header); | |
1220 | ||
1221 | /* | |
1222 | * Check if enough free space is available in the inode to shift the | |
1223 | * entries ahead by new_extra_isize. | |
1224 | */ | |
1225 | ||
1226 | base = start = entry; | |
1227 | end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; | |
1228 | min_offs = end - base; | |
1229 | last = entry; | |
1230 | total_ino = sizeof(struct ext4_xattr_ibody_header); | |
1231 | ||
1232 | free = ext4_xattr_free_space(last, &min_offs, base, &total_ino); | |
1233 | if (free >= new_extra_isize) { | |
1234 | entry = IFIRST(header); | |
1235 | ext4_xattr_shift_entries(entry, EXT4_I(inode)->i_extra_isize | |
1236 | - new_extra_isize, (void *)raw_inode + | |
1237 | EXT4_GOOD_OLD_INODE_SIZE + new_extra_isize, | |
1238 | (void *)header, total_ino, | |
1239 | inode->i_sb->s_blocksize); | |
1240 | EXT4_I(inode)->i_extra_isize = new_extra_isize; | |
1241 | error = 0; | |
1242 | goto cleanup; | |
1243 | } | |
1244 | ||
1245 | /* | |
1246 | * Enough free space isn't available in the inode, check if | |
1247 | * EA block can hold new_extra_isize bytes. | |
1248 | */ | |
1249 | if (EXT4_I(inode)->i_file_acl) { | |
1250 | bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl); | |
1251 | error = -EIO; | |
1252 | if (!bh) | |
1253 | goto cleanup; | |
cc8e94fd | 1254 | if (ext4_xattr_check_block(inode, bh)) { |
24676da4 TT |
1255 | EXT4_ERROR_INODE(inode, "bad block %llu", |
1256 | EXT4_I(inode)->i_file_acl); | |
6dd4ee7c KS |
1257 | error = -EIO; |
1258 | goto cleanup; | |
1259 | } | |
1260 | base = BHDR(bh); | |
1261 | first = BFIRST(bh); | |
1262 | end = bh->b_data + bh->b_size; | |
1263 | min_offs = end - base; | |
1264 | free = ext4_xattr_free_space(first, &min_offs, base, | |
1265 | &total_blk); | |
1266 | if (free < new_extra_isize) { | |
1267 | if (!tried_min_extra_isize && s_min_extra_isize) { | |
1268 | tried_min_extra_isize++; | |
1269 | new_extra_isize = s_min_extra_isize; | |
1270 | brelse(bh); | |
1271 | goto retry; | |
1272 | } | |
1273 | error = -1; | |
1274 | goto cleanup; | |
1275 | } | |
1276 | } else { | |
1277 | free = inode->i_sb->s_blocksize; | |
1278 | } | |
1279 | ||
1280 | while (new_extra_isize > 0) { | |
1281 | size_t offs, size, entry_size; | |
1282 | struct ext4_xattr_entry *small_entry = NULL; | |
1283 | struct ext4_xattr_info i = { | |
1284 | .value = NULL, | |
1285 | .value_len = 0, | |
1286 | }; | |
1287 | unsigned int total_size; /* EA entry size + value size */ | |
1288 | unsigned int shift_bytes; /* No. of bytes to shift EAs by? */ | |
1289 | unsigned int min_total_size = ~0U; | |
1290 | ||
1291 | is = kzalloc(sizeof(struct ext4_xattr_ibody_find), GFP_NOFS); | |
1292 | bs = kzalloc(sizeof(struct ext4_xattr_block_find), GFP_NOFS); | |
1293 | if (!is || !bs) { | |
1294 | error = -ENOMEM; | |
1295 | goto cleanup; | |
1296 | } | |
1297 | ||
1298 | is->s.not_found = -ENODATA; | |
1299 | bs->s.not_found = -ENODATA; | |
1300 | is->iloc.bh = NULL; | |
1301 | bs->bh = NULL; | |
1302 | ||
1303 | last = IFIRST(header); | |
1304 | /* Find the entry best suited to be pushed into EA block */ | |
1305 | entry = NULL; | |
1306 | for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) { | |
1307 | total_size = | |
1308 | EXT4_XATTR_SIZE(le32_to_cpu(last->e_value_size)) + | |
1309 | EXT4_XATTR_LEN(last->e_name_len); | |
1310 | if (total_size <= free && total_size < min_total_size) { | |
1311 | if (total_size < new_extra_isize) { | |
1312 | small_entry = last; | |
1313 | } else { | |
1314 | entry = last; | |
1315 | min_total_size = total_size; | |
1316 | } | |
1317 | } | |
1318 | } | |
1319 | ||
1320 | if (entry == NULL) { | |
1321 | if (small_entry) { | |
1322 | entry = small_entry; | |
1323 | } else { | |
1324 | if (!tried_min_extra_isize && | |
1325 | s_min_extra_isize) { | |
1326 | tried_min_extra_isize++; | |
1327 | new_extra_isize = s_min_extra_isize; | |
1328 | goto retry; | |
1329 | } | |
1330 | error = -1; | |
1331 | goto cleanup; | |
1332 | } | |
1333 | } | |
1334 | offs = le16_to_cpu(entry->e_value_offs); | |
1335 | size = le32_to_cpu(entry->e_value_size); | |
1336 | entry_size = EXT4_XATTR_LEN(entry->e_name_len); | |
1337 | i.name_index = entry->e_name_index, | |
1338 | buffer = kmalloc(EXT4_XATTR_SIZE(size), GFP_NOFS); | |
1339 | b_entry_name = kmalloc(entry->e_name_len + 1, GFP_NOFS); | |
1340 | if (!buffer || !b_entry_name) { | |
1341 | error = -ENOMEM; | |
1342 | goto cleanup; | |
1343 | } | |
1344 | /* Save the entry name and the entry value */ | |
1345 | memcpy(buffer, (void *)IFIRST(header) + offs, | |
1346 | EXT4_XATTR_SIZE(size)); | |
1347 | memcpy(b_entry_name, entry->e_name, entry->e_name_len); | |
1348 | b_entry_name[entry->e_name_len] = '\0'; | |
1349 | i.name = b_entry_name; | |
1350 | ||
1351 | error = ext4_get_inode_loc(inode, &is->iloc); | |
1352 | if (error) | |
1353 | goto cleanup; | |
1354 | ||
1355 | error = ext4_xattr_ibody_find(inode, &i, is); | |
1356 | if (error) | |
1357 | goto cleanup; | |
1358 | ||
1359 | /* Remove the chosen entry from the inode */ | |
1360 | error = ext4_xattr_ibody_set(handle, inode, &i, is); | |
9aaab058 RK |
1361 | if (error) |
1362 | goto cleanup; | |
6dd4ee7c KS |
1363 | |
1364 | entry = IFIRST(header); | |
1365 | if (entry_size + EXT4_XATTR_SIZE(size) >= new_extra_isize) | |
1366 | shift_bytes = new_extra_isize; | |
1367 | else | |
1368 | shift_bytes = entry_size + size; | |
1369 | /* Adjust the offsets and shift the remaining entries ahead */ | |
1370 | ext4_xattr_shift_entries(entry, EXT4_I(inode)->i_extra_isize - | |
1371 | shift_bytes, (void *)raw_inode + | |
1372 | EXT4_GOOD_OLD_INODE_SIZE + extra_isize + shift_bytes, | |
1373 | (void *)header, total_ino - entry_size, | |
1374 | inode->i_sb->s_blocksize); | |
1375 | ||
1376 | extra_isize += shift_bytes; | |
1377 | new_extra_isize -= shift_bytes; | |
1378 | EXT4_I(inode)->i_extra_isize = extra_isize; | |
1379 | ||
1380 | i.name = b_entry_name; | |
1381 | i.value = buffer; | |
ac39849d | 1382 | i.value_len = size; |
6dd4ee7c KS |
1383 | error = ext4_xattr_block_find(inode, &i, bs); |
1384 | if (error) | |
1385 | goto cleanup; | |
1386 | ||
1387 | /* Add entry which was removed from the inode into the block */ | |
1388 | error = ext4_xattr_block_set(handle, inode, &i, bs); | |
1389 | if (error) | |
1390 | goto cleanup; | |
1391 | kfree(b_entry_name); | |
1392 | kfree(buffer); | |
d3533d72 JL |
1393 | b_entry_name = NULL; |
1394 | buffer = NULL; | |
6dd4ee7c KS |
1395 | brelse(is->iloc.bh); |
1396 | kfree(is); | |
1397 | kfree(bs); | |
1398 | } | |
1399 | brelse(bh); | |
1400 | up_write(&EXT4_I(inode)->xattr_sem); | |
1401 | return 0; | |
1402 | ||
1403 | cleanup: | |
1404 | kfree(b_entry_name); | |
1405 | kfree(buffer); | |
1406 | if (is) | |
1407 | brelse(is->iloc.bh); | |
1408 | kfree(is); | |
1409 | kfree(bs); | |
1410 | brelse(bh); | |
1411 | up_write(&EXT4_I(inode)->xattr_sem); | |
1412 | return error; | |
1413 | } | |
1414 | ||
1415 | ||
1416 | ||
ac27a0ec | 1417 | /* |
617ba13b | 1418 | * ext4_xattr_delete_inode() |
ac27a0ec DK |
1419 | * |
1420 | * Free extended attribute resources associated with this inode. This | |
1421 | * is called immediately before an inode is freed. We have exclusive | |
1422 | * access to the inode. | |
1423 | */ | |
1424 | void | |
617ba13b | 1425 | ext4_xattr_delete_inode(handle_t *handle, struct inode *inode) |
ac27a0ec DK |
1426 | { |
1427 | struct buffer_head *bh = NULL; | |
1428 | ||
617ba13b | 1429 | if (!EXT4_I(inode)->i_file_acl) |
ac27a0ec | 1430 | goto cleanup; |
617ba13b | 1431 | bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl); |
ac27a0ec | 1432 | if (!bh) { |
24676da4 TT |
1433 | EXT4_ERROR_INODE(inode, "block %llu read error", |
1434 | EXT4_I(inode)->i_file_acl); | |
ac27a0ec DK |
1435 | goto cleanup; |
1436 | } | |
617ba13b | 1437 | if (BHDR(bh)->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC) || |
ac27a0ec | 1438 | BHDR(bh)->h_blocks != cpu_to_le32(1)) { |
24676da4 TT |
1439 | EXT4_ERROR_INODE(inode, "bad block %llu", |
1440 | EXT4_I(inode)->i_file_acl); | |
ac27a0ec DK |
1441 | goto cleanup; |
1442 | } | |
617ba13b MC |
1443 | ext4_xattr_release_block(handle, inode, bh); |
1444 | EXT4_I(inode)->i_file_acl = 0; | |
ac27a0ec DK |
1445 | |
1446 | cleanup: | |
1447 | brelse(bh); | |
1448 | } | |
1449 | ||
1450 | /* | |
617ba13b | 1451 | * ext4_xattr_put_super() |
ac27a0ec DK |
1452 | * |
1453 | * This is called when a file system is unmounted. | |
1454 | */ | |
1455 | void | |
617ba13b | 1456 | ext4_xattr_put_super(struct super_block *sb) |
ac27a0ec DK |
1457 | { |
1458 | mb_cache_shrink(sb->s_bdev); | |
1459 | } | |
1460 | ||
1461 | /* | |
617ba13b | 1462 | * ext4_xattr_cache_insert() |
ac27a0ec DK |
1463 | * |
1464 | * Create a new entry in the extended attribute cache, and insert | |
1465 | * it unless such an entry is already in the cache. | |
1466 | * | |
1467 | * Returns 0, or a negative error number on failure. | |
1468 | */ | |
1469 | static void | |
617ba13b | 1470 | ext4_xattr_cache_insert(struct buffer_head *bh) |
ac27a0ec DK |
1471 | { |
1472 | __u32 hash = le32_to_cpu(BHDR(bh)->h_hash); | |
1473 | struct mb_cache_entry *ce; | |
1474 | int error; | |
1475 | ||
335e92e8 | 1476 | ce = mb_cache_entry_alloc(ext4_xattr_cache, GFP_NOFS); |
ac27a0ec DK |
1477 | if (!ce) { |
1478 | ea_bdebug(bh, "out of memory"); | |
1479 | return; | |
1480 | } | |
2aec7c52 | 1481 | error = mb_cache_entry_insert(ce, bh->b_bdev, bh->b_blocknr, hash); |
ac27a0ec DK |
1482 | if (error) { |
1483 | mb_cache_entry_free(ce); | |
1484 | if (error == -EBUSY) { | |
1485 | ea_bdebug(bh, "already in cache"); | |
1486 | error = 0; | |
1487 | } | |
1488 | } else { | |
1489 | ea_bdebug(bh, "inserting [%x]", (int)hash); | |
1490 | mb_cache_entry_release(ce); | |
1491 | } | |
1492 | } | |
1493 | ||
1494 | /* | |
617ba13b | 1495 | * ext4_xattr_cmp() |
ac27a0ec DK |
1496 | * |
1497 | * Compare two extended attribute blocks for equality. | |
1498 | * | |
1499 | * Returns 0 if the blocks are equal, 1 if they differ, and | |
1500 | * a negative error number on errors. | |
1501 | */ | |
1502 | static int | |
617ba13b MC |
1503 | ext4_xattr_cmp(struct ext4_xattr_header *header1, |
1504 | struct ext4_xattr_header *header2) | |
ac27a0ec | 1505 | { |
617ba13b | 1506 | struct ext4_xattr_entry *entry1, *entry2; |
ac27a0ec DK |
1507 | |
1508 | entry1 = ENTRY(header1+1); | |
1509 | entry2 = ENTRY(header2+1); | |
1510 | while (!IS_LAST_ENTRY(entry1)) { | |
1511 | if (IS_LAST_ENTRY(entry2)) | |
1512 | return 1; | |
1513 | if (entry1->e_hash != entry2->e_hash || | |
1514 | entry1->e_name_index != entry2->e_name_index || | |
1515 | entry1->e_name_len != entry2->e_name_len || | |
1516 | entry1->e_value_size != entry2->e_value_size || | |
1517 | memcmp(entry1->e_name, entry2->e_name, entry1->e_name_len)) | |
1518 | return 1; | |
1519 | if (entry1->e_value_block != 0 || entry2->e_value_block != 0) | |
1520 | return -EIO; | |
1521 | if (memcmp((char *)header1 + le16_to_cpu(entry1->e_value_offs), | |
1522 | (char *)header2 + le16_to_cpu(entry2->e_value_offs), | |
1523 | le32_to_cpu(entry1->e_value_size))) | |
1524 | return 1; | |
1525 | ||
617ba13b MC |
1526 | entry1 = EXT4_XATTR_NEXT(entry1); |
1527 | entry2 = EXT4_XATTR_NEXT(entry2); | |
ac27a0ec DK |
1528 | } |
1529 | if (!IS_LAST_ENTRY(entry2)) | |
1530 | return 1; | |
1531 | return 0; | |
1532 | } | |
1533 | ||
1534 | /* | |
617ba13b | 1535 | * ext4_xattr_cache_find() |
ac27a0ec DK |
1536 | * |
1537 | * Find an identical extended attribute block. | |
1538 | * | |
1539 | * Returns a pointer to the block found, or NULL if such a block was | |
1540 | * not found or an error occurred. | |
1541 | */ | |
1542 | static struct buffer_head * | |
617ba13b | 1543 | ext4_xattr_cache_find(struct inode *inode, struct ext4_xattr_header *header, |
ac27a0ec DK |
1544 | struct mb_cache_entry **pce) |
1545 | { | |
1546 | __u32 hash = le32_to_cpu(header->h_hash); | |
1547 | struct mb_cache_entry *ce; | |
1548 | ||
1549 | if (!header->h_hash) | |
1550 | return NULL; /* never share */ | |
1551 | ea_idebug(inode, "looking for cached blocks [%x]", (int)hash); | |
1552 | again: | |
2aec7c52 AG |
1553 | ce = mb_cache_entry_find_first(ext4_xattr_cache, inode->i_sb->s_bdev, |
1554 | hash); | |
ac27a0ec DK |
1555 | while (ce) { |
1556 | struct buffer_head *bh; | |
1557 | ||
1558 | if (IS_ERR(ce)) { | |
1559 | if (PTR_ERR(ce) == -EAGAIN) | |
1560 | goto again; | |
1561 | break; | |
1562 | } | |
1563 | bh = sb_bread(inode->i_sb, ce->e_block); | |
1564 | if (!bh) { | |
24676da4 TT |
1565 | EXT4_ERROR_INODE(inode, "block %lu read error", |
1566 | (unsigned long) ce->e_block); | |
ac27a0ec | 1567 | } else if (le32_to_cpu(BHDR(bh)->h_refcount) >= |
617ba13b | 1568 | EXT4_XATTR_REFCOUNT_MAX) { |
ac27a0ec DK |
1569 | ea_idebug(inode, "block %lu refcount %d>=%d", |
1570 | (unsigned long) ce->e_block, | |
1571 | le32_to_cpu(BHDR(bh)->h_refcount), | |
617ba13b MC |
1572 | EXT4_XATTR_REFCOUNT_MAX); |
1573 | } else if (ext4_xattr_cmp(header, BHDR(bh)) == 0) { | |
ac27a0ec DK |
1574 | *pce = ce; |
1575 | return bh; | |
1576 | } | |
1577 | brelse(bh); | |
2aec7c52 | 1578 | ce = mb_cache_entry_find_next(ce, inode->i_sb->s_bdev, hash); |
ac27a0ec DK |
1579 | } |
1580 | return NULL; | |
1581 | } | |
1582 | ||
1583 | #define NAME_HASH_SHIFT 5 | |
1584 | #define VALUE_HASH_SHIFT 16 | |
1585 | ||
1586 | /* | |
617ba13b | 1587 | * ext4_xattr_hash_entry() |
ac27a0ec DK |
1588 | * |
1589 | * Compute the hash of an extended attribute. | |
1590 | */ | |
617ba13b MC |
1591 | static inline void ext4_xattr_hash_entry(struct ext4_xattr_header *header, |
1592 | struct ext4_xattr_entry *entry) | |
ac27a0ec DK |
1593 | { |
1594 | __u32 hash = 0; | |
1595 | char *name = entry->e_name; | |
1596 | int n; | |
1597 | ||
2b2d6d01 | 1598 | for (n = 0; n < entry->e_name_len; n++) { |
ac27a0ec DK |
1599 | hash = (hash << NAME_HASH_SHIFT) ^ |
1600 | (hash >> (8*sizeof(hash) - NAME_HASH_SHIFT)) ^ | |
1601 | *name++; | |
1602 | } | |
1603 | ||
1604 | if (entry->e_value_block == 0 && entry->e_value_size != 0) { | |
1605 | __le32 *value = (__le32 *)((char *)header + | |
1606 | le16_to_cpu(entry->e_value_offs)); | |
1607 | for (n = (le32_to_cpu(entry->e_value_size) + | |
617ba13b | 1608 | EXT4_XATTR_ROUND) >> EXT4_XATTR_PAD_BITS; n; n--) { |
ac27a0ec DK |
1609 | hash = (hash << VALUE_HASH_SHIFT) ^ |
1610 | (hash >> (8*sizeof(hash) - VALUE_HASH_SHIFT)) ^ | |
1611 | le32_to_cpu(*value++); | |
1612 | } | |
1613 | } | |
1614 | entry->e_hash = cpu_to_le32(hash); | |
1615 | } | |
1616 | ||
1617 | #undef NAME_HASH_SHIFT | |
1618 | #undef VALUE_HASH_SHIFT | |
1619 | ||
1620 | #define BLOCK_HASH_SHIFT 16 | |
1621 | ||
1622 | /* | |
617ba13b | 1623 | * ext4_xattr_rehash() |
ac27a0ec DK |
1624 | * |
1625 | * Re-compute the extended attribute hash value after an entry has changed. | |
1626 | */ | |
617ba13b MC |
1627 | static void ext4_xattr_rehash(struct ext4_xattr_header *header, |
1628 | struct ext4_xattr_entry *entry) | |
ac27a0ec | 1629 | { |
617ba13b | 1630 | struct ext4_xattr_entry *here; |
ac27a0ec DK |
1631 | __u32 hash = 0; |
1632 | ||
617ba13b | 1633 | ext4_xattr_hash_entry(header, entry); |
ac27a0ec DK |
1634 | here = ENTRY(header+1); |
1635 | while (!IS_LAST_ENTRY(here)) { | |
1636 | if (!here->e_hash) { | |
1637 | /* Block is not shared if an entry's hash value == 0 */ | |
1638 | hash = 0; | |
1639 | break; | |
1640 | } | |
1641 | hash = (hash << BLOCK_HASH_SHIFT) ^ | |
1642 | (hash >> (8*sizeof(hash) - BLOCK_HASH_SHIFT)) ^ | |
1643 | le32_to_cpu(here->e_hash); | |
617ba13b | 1644 | here = EXT4_XATTR_NEXT(here); |
ac27a0ec DK |
1645 | } |
1646 | header->h_hash = cpu_to_le32(hash); | |
1647 | } | |
1648 | ||
1649 | #undef BLOCK_HASH_SHIFT | |
1650 | ||
1651 | int __init | |
5dabfc78 | 1652 | ext4_init_xattr(void) |
ac27a0ec | 1653 | { |
2aec7c52 | 1654 | ext4_xattr_cache = mb_cache_create("ext4_xattr", 6); |
617ba13b | 1655 | if (!ext4_xattr_cache) |
ac27a0ec DK |
1656 | return -ENOMEM; |
1657 | return 0; | |
1658 | } | |
1659 | ||
1660 | void | |
5dabfc78 | 1661 | ext4_exit_xattr(void) |
ac27a0ec | 1662 | { |
617ba13b MC |
1663 | if (ext4_xattr_cache) |
1664 | mb_cache_destroy(ext4_xattr_cache); | |
1665 | ext4_xattr_cache = NULL; | |
ac27a0ec | 1666 | } |