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 | 64 | #ifdef EXT4_XATTR_DEBUG |
ac27a0ec DK |
65 | # define ea_idebug(inode, f...) do { \ |
66 | printk(KERN_DEBUG "inode %s:%lu: ", \ | |
67 | inode->i_sb->s_id, inode->i_ino); \ | |
68 | printk(f); \ | |
69 | printk("\n"); \ | |
70 | } while (0) | |
71 | # define ea_bdebug(bh, f...) do { \ | |
72 | char b[BDEVNAME_SIZE]; \ | |
73 | printk(KERN_DEBUG "block %s:%lu: ", \ | |
74 | bdevname(bh->b_bdev, b), \ | |
75 | (unsigned long) bh->b_blocknr); \ | |
76 | printk(f); \ | |
77 | printk("\n"); \ | |
78 | } while (0) | |
79 | #else | |
ace36ad4 JP |
80 | # define ea_idebug(inode, fmt, ...) no_printk(fmt, ##__VA_ARGS__) |
81 | # define ea_bdebug(bh, fmt, ...) no_printk(fmt, ##__VA_ARGS__) | |
ac27a0ec DK |
82 | #endif |
83 | ||
9c191f70 | 84 | static void ext4_xattr_cache_insert(struct mb_cache *, struct buffer_head *); |
617ba13b MC |
85 | static struct buffer_head *ext4_xattr_cache_find(struct inode *, |
86 | struct ext4_xattr_header *, | |
ac27a0ec | 87 | struct mb_cache_entry **); |
617ba13b MC |
88 | static void ext4_xattr_rehash(struct ext4_xattr_header *, |
89 | struct ext4_xattr_entry *); | |
431547b3 | 90 | static int ext4_xattr_list(struct dentry *dentry, char *buffer, |
d3a95d47 | 91 | size_t buffer_size); |
ac27a0ec | 92 | |
11e27528 | 93 | static const struct xattr_handler *ext4_xattr_handler_map[] = { |
617ba13b | 94 | [EXT4_XATTR_INDEX_USER] = &ext4_xattr_user_handler, |
03010a33 | 95 | #ifdef CONFIG_EXT4_FS_POSIX_ACL |
64e178a7 CH |
96 | [EXT4_XATTR_INDEX_POSIX_ACL_ACCESS] = &posix_acl_access_xattr_handler, |
97 | [EXT4_XATTR_INDEX_POSIX_ACL_DEFAULT] = &posix_acl_default_xattr_handler, | |
ac27a0ec | 98 | #endif |
617ba13b | 99 | [EXT4_XATTR_INDEX_TRUSTED] = &ext4_xattr_trusted_handler, |
03010a33 | 100 | #ifdef CONFIG_EXT4_FS_SECURITY |
617ba13b | 101 | [EXT4_XATTR_INDEX_SECURITY] = &ext4_xattr_security_handler, |
ac27a0ec DK |
102 | #endif |
103 | }; | |
104 | ||
11e27528 | 105 | const struct xattr_handler *ext4_xattr_handlers[] = { |
617ba13b MC |
106 | &ext4_xattr_user_handler, |
107 | &ext4_xattr_trusted_handler, | |
03010a33 | 108 | #ifdef CONFIG_EXT4_FS_POSIX_ACL |
64e178a7 CH |
109 | &posix_acl_access_xattr_handler, |
110 | &posix_acl_default_xattr_handler, | |
ac27a0ec | 111 | #endif |
03010a33 | 112 | #ifdef CONFIG_EXT4_FS_SECURITY |
617ba13b | 113 | &ext4_xattr_security_handler, |
ac27a0ec DK |
114 | #endif |
115 | NULL | |
116 | }; | |
117 | ||
9c191f70 M |
118 | #define EXT4_GET_MB_CACHE(inode) (((struct ext4_sb_info *) \ |
119 | inode->i_sb->s_fs_info)->s_mb_cache) | |
120 | ||
cc8e94fd DW |
121 | static __le32 ext4_xattr_block_csum(struct inode *inode, |
122 | sector_t block_nr, | |
123 | struct ext4_xattr_header *hdr) | |
124 | { | |
125 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); | |
d6a77105 TT |
126 | __u32 csum; |
127 | __le32 save_csum; | |
128 | __le64 dsk_block_nr = cpu_to_le64(block_nr); | |
cc8e94fd | 129 | |
d6a77105 | 130 | save_csum = hdr->h_checksum; |
cc8e94fd | 131 | hdr->h_checksum = 0; |
d6a77105 TT |
132 | csum = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&dsk_block_nr, |
133 | sizeof(dsk_block_nr)); | |
cc8e94fd DW |
134 | csum = ext4_chksum(sbi, csum, (__u8 *)hdr, |
135 | EXT4_BLOCK_SIZE(inode->i_sb)); | |
41eb70dd | 136 | |
d6a77105 | 137 | hdr->h_checksum = save_csum; |
cc8e94fd DW |
138 | return cpu_to_le32(csum); |
139 | } | |
140 | ||
141 | static int ext4_xattr_block_csum_verify(struct inode *inode, | |
142 | sector_t block_nr, | |
143 | struct ext4_xattr_header *hdr) | |
144 | { | |
145 | if (EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb, | |
146 | EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) && | |
147 | (hdr->h_checksum != ext4_xattr_block_csum(inode, block_nr, hdr))) | |
148 | return 0; | |
149 | return 1; | |
150 | } | |
151 | ||
152 | static void ext4_xattr_block_csum_set(struct inode *inode, | |
153 | sector_t block_nr, | |
154 | struct ext4_xattr_header *hdr) | |
155 | { | |
156 | if (!EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb, | |
157 | EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) | |
158 | return; | |
159 | ||
160 | hdr->h_checksum = ext4_xattr_block_csum(inode, block_nr, hdr); | |
161 | } | |
162 | ||
163 | static inline int ext4_handle_dirty_xattr_block(handle_t *handle, | |
164 | struct inode *inode, | |
165 | struct buffer_head *bh) | |
166 | { | |
167 | ext4_xattr_block_csum_set(inode, bh->b_blocknr, BHDR(bh)); | |
168 | return ext4_handle_dirty_metadata(handle, inode, bh); | |
169 | } | |
170 | ||
11e27528 | 171 | static inline const struct xattr_handler * |
617ba13b | 172 | ext4_xattr_handler(int name_index) |
ac27a0ec | 173 | { |
11e27528 | 174 | const struct xattr_handler *handler = NULL; |
ac27a0ec | 175 | |
617ba13b MC |
176 | if (name_index > 0 && name_index < ARRAY_SIZE(ext4_xattr_handler_map)) |
177 | handler = ext4_xattr_handler_map[name_index]; | |
ac27a0ec DK |
178 | return handler; |
179 | } | |
180 | ||
181 | /* | |
182 | * Inode operation listxattr() | |
183 | * | |
184 | * dentry->d_inode->i_mutex: don't care | |
185 | */ | |
186 | ssize_t | |
617ba13b | 187 | ext4_listxattr(struct dentry *dentry, char *buffer, size_t size) |
ac27a0ec | 188 | { |
431547b3 | 189 | return ext4_xattr_list(dentry, buffer, size); |
ac27a0ec DK |
190 | } |
191 | ||
192 | static int | |
617ba13b | 193 | ext4_xattr_check_names(struct ext4_xattr_entry *entry, void *end) |
ac27a0ec DK |
194 | { |
195 | while (!IS_LAST_ENTRY(entry)) { | |
617ba13b | 196 | struct ext4_xattr_entry *next = EXT4_XATTR_NEXT(entry); |
ac27a0ec DK |
197 | if ((void *)next >= end) |
198 | return -EIO; | |
199 | entry = next; | |
200 | } | |
201 | return 0; | |
202 | } | |
203 | ||
204 | static inline int | |
cc8e94fd | 205 | ext4_xattr_check_block(struct inode *inode, struct buffer_head *bh) |
ac27a0ec | 206 | { |
cc8e94fd DW |
207 | int error; |
208 | ||
209 | if (buffer_verified(bh)) | |
210 | return 0; | |
211 | ||
617ba13b | 212 | if (BHDR(bh)->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC) || |
ac27a0ec DK |
213 | BHDR(bh)->h_blocks != cpu_to_le32(1)) |
214 | return -EIO; | |
cc8e94fd DW |
215 | if (!ext4_xattr_block_csum_verify(inode, bh->b_blocknr, BHDR(bh))) |
216 | return -EIO; | |
217 | error = ext4_xattr_check_names(BFIRST(bh), bh->b_data + bh->b_size); | |
218 | if (!error) | |
219 | set_buffer_verified(bh); | |
220 | return error; | |
ac27a0ec DK |
221 | } |
222 | ||
223 | static inline int | |
617ba13b | 224 | ext4_xattr_check_entry(struct ext4_xattr_entry *entry, size_t size) |
ac27a0ec DK |
225 | { |
226 | size_t value_size = le32_to_cpu(entry->e_value_size); | |
227 | ||
228 | if (entry->e_value_block != 0 || value_size > size || | |
229 | le16_to_cpu(entry->e_value_offs) + value_size > size) | |
230 | return -EIO; | |
231 | return 0; | |
232 | } | |
233 | ||
234 | static int | |
617ba13b | 235 | ext4_xattr_find_entry(struct ext4_xattr_entry **pentry, int name_index, |
ac27a0ec DK |
236 | const char *name, size_t size, int sorted) |
237 | { | |
617ba13b | 238 | struct ext4_xattr_entry *entry; |
ac27a0ec DK |
239 | size_t name_len; |
240 | int cmp = 1; | |
241 | ||
242 | if (name == NULL) | |
243 | return -EINVAL; | |
244 | name_len = strlen(name); | |
245 | entry = *pentry; | |
617ba13b | 246 | for (; !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) { |
ac27a0ec DK |
247 | cmp = name_index - entry->e_name_index; |
248 | if (!cmp) | |
249 | cmp = name_len - entry->e_name_len; | |
250 | if (!cmp) | |
251 | cmp = memcmp(name, entry->e_name, name_len); | |
252 | if (cmp <= 0 && (sorted || cmp == 0)) | |
253 | break; | |
254 | } | |
255 | *pentry = entry; | |
617ba13b | 256 | if (!cmp && ext4_xattr_check_entry(entry, size)) |
ac27a0ec DK |
257 | return -EIO; |
258 | return cmp ? -ENODATA : 0; | |
259 | } | |
260 | ||
261 | static int | |
617ba13b | 262 | ext4_xattr_block_get(struct inode *inode, int name_index, const char *name, |
ac27a0ec DK |
263 | void *buffer, size_t buffer_size) |
264 | { | |
265 | struct buffer_head *bh = NULL; | |
617ba13b | 266 | struct ext4_xattr_entry *entry; |
ac27a0ec DK |
267 | size_t size; |
268 | int error; | |
9c191f70 | 269 | struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode); |
ac27a0ec DK |
270 | |
271 | ea_idebug(inode, "name=%d.%s, buffer=%p, buffer_size=%ld", | |
272 | name_index, name, buffer, (long)buffer_size); | |
273 | ||
274 | error = -ENODATA; | |
617ba13b | 275 | if (!EXT4_I(inode)->i_file_acl) |
ac27a0ec | 276 | goto cleanup; |
ace36ad4 JP |
277 | ea_idebug(inode, "reading block %llu", |
278 | (unsigned long long)EXT4_I(inode)->i_file_acl); | |
617ba13b | 279 | bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl); |
ac27a0ec DK |
280 | if (!bh) |
281 | goto cleanup; | |
282 | ea_bdebug(bh, "b_count=%d, refcount=%d", | |
283 | atomic_read(&(bh->b_count)), le32_to_cpu(BHDR(bh)->h_refcount)); | |
cc8e94fd | 284 | if (ext4_xattr_check_block(inode, bh)) { |
12062ddd | 285 | bad_block: |
24676da4 TT |
286 | EXT4_ERROR_INODE(inode, "bad block %llu", |
287 | EXT4_I(inode)->i_file_acl); | |
ac27a0ec DK |
288 | error = -EIO; |
289 | goto cleanup; | |
290 | } | |
9c191f70 | 291 | ext4_xattr_cache_insert(ext4_mb_cache, bh); |
ac27a0ec | 292 | entry = BFIRST(bh); |
617ba13b | 293 | error = ext4_xattr_find_entry(&entry, name_index, name, bh->b_size, 1); |
ac27a0ec DK |
294 | if (error == -EIO) |
295 | goto bad_block; | |
296 | if (error) | |
297 | goto cleanup; | |
298 | size = le32_to_cpu(entry->e_value_size); | |
299 | if (buffer) { | |
300 | error = -ERANGE; | |
301 | if (size > buffer_size) | |
302 | goto cleanup; | |
303 | memcpy(buffer, bh->b_data + le16_to_cpu(entry->e_value_offs), | |
304 | size); | |
305 | } | |
306 | error = size; | |
307 | ||
308 | cleanup: | |
309 | brelse(bh); | |
310 | return error; | |
311 | } | |
312 | ||
879b3825 | 313 | int |
617ba13b | 314 | ext4_xattr_ibody_get(struct inode *inode, int name_index, const char *name, |
ac27a0ec DK |
315 | void *buffer, size_t buffer_size) |
316 | { | |
617ba13b MC |
317 | struct ext4_xattr_ibody_header *header; |
318 | struct ext4_xattr_entry *entry; | |
319 | struct ext4_inode *raw_inode; | |
320 | struct ext4_iloc iloc; | |
ac27a0ec DK |
321 | size_t size; |
322 | void *end; | |
323 | int error; | |
324 | ||
19f5fb7a | 325 | if (!ext4_test_inode_state(inode, EXT4_STATE_XATTR)) |
ac27a0ec | 326 | return -ENODATA; |
617ba13b | 327 | error = ext4_get_inode_loc(inode, &iloc); |
ac27a0ec DK |
328 | if (error) |
329 | return error; | |
617ba13b | 330 | raw_inode = ext4_raw_inode(&iloc); |
ac27a0ec DK |
331 | header = IHDR(inode, raw_inode); |
332 | entry = IFIRST(header); | |
617ba13b MC |
333 | end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; |
334 | error = ext4_xattr_check_names(entry, end); | |
ac27a0ec DK |
335 | if (error) |
336 | goto cleanup; | |
617ba13b | 337 | error = ext4_xattr_find_entry(&entry, name_index, name, |
ac27a0ec DK |
338 | end - (void *)entry, 0); |
339 | if (error) | |
340 | goto cleanup; | |
341 | size = le32_to_cpu(entry->e_value_size); | |
342 | if (buffer) { | |
343 | error = -ERANGE; | |
344 | if (size > buffer_size) | |
345 | goto cleanup; | |
346 | memcpy(buffer, (void *)IFIRST(header) + | |
347 | le16_to_cpu(entry->e_value_offs), size); | |
348 | } | |
349 | error = size; | |
350 | ||
351 | cleanup: | |
352 | brelse(iloc.bh); | |
353 | return error; | |
354 | } | |
355 | ||
356 | /* | |
617ba13b | 357 | * ext4_xattr_get() |
ac27a0ec DK |
358 | * |
359 | * Copy an extended attribute into the buffer | |
360 | * provided, or compute the buffer size required. | |
361 | * Buffer is NULL to compute the size of the buffer required. | |
362 | * | |
363 | * Returns a negative error number on failure, or the number of bytes | |
364 | * used / required on success. | |
365 | */ | |
366 | int | |
617ba13b | 367 | ext4_xattr_get(struct inode *inode, int name_index, const char *name, |
ac27a0ec DK |
368 | void *buffer, size_t buffer_size) |
369 | { | |
370 | int error; | |
371 | ||
617ba13b MC |
372 | down_read(&EXT4_I(inode)->xattr_sem); |
373 | error = ext4_xattr_ibody_get(inode, name_index, name, buffer, | |
ac27a0ec DK |
374 | buffer_size); |
375 | if (error == -ENODATA) | |
617ba13b | 376 | error = ext4_xattr_block_get(inode, name_index, name, buffer, |
ac27a0ec | 377 | buffer_size); |
617ba13b | 378 | up_read(&EXT4_I(inode)->xattr_sem); |
ac27a0ec DK |
379 | return error; |
380 | } | |
381 | ||
382 | static int | |
431547b3 | 383 | ext4_xattr_list_entries(struct dentry *dentry, struct ext4_xattr_entry *entry, |
ac27a0ec DK |
384 | char *buffer, size_t buffer_size) |
385 | { | |
386 | size_t rest = buffer_size; | |
387 | ||
617ba13b | 388 | for (; !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) { |
11e27528 | 389 | const struct xattr_handler *handler = |
617ba13b | 390 | ext4_xattr_handler(entry->e_name_index); |
ac27a0ec DK |
391 | |
392 | if (handler) { | |
431547b3 | 393 | size_t size = handler->list(dentry, buffer, rest, |
ac27a0ec | 394 | entry->e_name, |
431547b3 CH |
395 | entry->e_name_len, |
396 | handler->flags); | |
ac27a0ec DK |
397 | if (buffer) { |
398 | if (size > rest) | |
399 | return -ERANGE; | |
400 | buffer += size; | |
401 | } | |
402 | rest -= size; | |
403 | } | |
404 | } | |
405 | return buffer_size - rest; | |
406 | } | |
407 | ||
408 | static int | |
431547b3 | 409 | ext4_xattr_block_list(struct dentry *dentry, char *buffer, size_t buffer_size) |
ac27a0ec | 410 | { |
431547b3 | 411 | struct inode *inode = dentry->d_inode; |
ac27a0ec DK |
412 | struct buffer_head *bh = NULL; |
413 | int error; | |
9c191f70 | 414 | struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode); |
ac27a0ec DK |
415 | |
416 | ea_idebug(inode, "buffer=%p, buffer_size=%ld", | |
417 | buffer, (long)buffer_size); | |
418 | ||
419 | error = 0; | |
617ba13b | 420 | if (!EXT4_I(inode)->i_file_acl) |
ac27a0ec | 421 | goto cleanup; |
ace36ad4 JP |
422 | ea_idebug(inode, "reading block %llu", |
423 | (unsigned long long)EXT4_I(inode)->i_file_acl); | |
617ba13b | 424 | bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl); |
ac27a0ec DK |
425 | error = -EIO; |
426 | if (!bh) | |
427 | goto cleanup; | |
428 | ea_bdebug(bh, "b_count=%d, refcount=%d", | |
429 | atomic_read(&(bh->b_count)), le32_to_cpu(BHDR(bh)->h_refcount)); | |
cc8e94fd | 430 | if (ext4_xattr_check_block(inode, bh)) { |
24676da4 TT |
431 | EXT4_ERROR_INODE(inode, "bad block %llu", |
432 | EXT4_I(inode)->i_file_acl); | |
ac27a0ec DK |
433 | error = -EIO; |
434 | goto cleanup; | |
435 | } | |
9c191f70 | 436 | ext4_xattr_cache_insert(ext4_mb_cache, bh); |
431547b3 | 437 | error = ext4_xattr_list_entries(dentry, BFIRST(bh), buffer, buffer_size); |
ac27a0ec DK |
438 | |
439 | cleanup: | |
440 | brelse(bh); | |
441 | ||
442 | return error; | |
443 | } | |
444 | ||
445 | static int | |
431547b3 | 446 | ext4_xattr_ibody_list(struct dentry *dentry, char *buffer, size_t buffer_size) |
ac27a0ec | 447 | { |
431547b3 | 448 | struct inode *inode = dentry->d_inode; |
617ba13b MC |
449 | struct ext4_xattr_ibody_header *header; |
450 | struct ext4_inode *raw_inode; | |
451 | struct ext4_iloc iloc; | |
ac27a0ec DK |
452 | void *end; |
453 | int error; | |
454 | ||
19f5fb7a | 455 | if (!ext4_test_inode_state(inode, EXT4_STATE_XATTR)) |
ac27a0ec | 456 | return 0; |
617ba13b | 457 | error = ext4_get_inode_loc(inode, &iloc); |
ac27a0ec DK |
458 | if (error) |
459 | return error; | |
617ba13b | 460 | raw_inode = ext4_raw_inode(&iloc); |
ac27a0ec | 461 | header = IHDR(inode, raw_inode); |
617ba13b MC |
462 | end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; |
463 | error = ext4_xattr_check_names(IFIRST(header), end); | |
ac27a0ec DK |
464 | if (error) |
465 | goto cleanup; | |
431547b3 | 466 | error = ext4_xattr_list_entries(dentry, IFIRST(header), |
ac27a0ec DK |
467 | buffer, buffer_size); |
468 | ||
469 | cleanup: | |
470 | brelse(iloc.bh); | |
471 | return error; | |
472 | } | |
473 | ||
474 | /* | |
617ba13b | 475 | * ext4_xattr_list() |
ac27a0ec DK |
476 | * |
477 | * Copy a list of attribute names into the buffer | |
478 | * provided, or compute the buffer size required. | |
479 | * Buffer is NULL to compute the size of the buffer required. | |
480 | * | |
481 | * Returns a negative error number on failure, or the number of bytes | |
482 | * used / required on success. | |
483 | */ | |
d3a95d47 | 484 | static int |
431547b3 | 485 | ext4_xattr_list(struct dentry *dentry, char *buffer, size_t buffer_size) |
ac27a0ec | 486 | { |
eaeef867 | 487 | int ret, ret2; |
ac27a0ec | 488 | |
431547b3 | 489 | down_read(&EXT4_I(dentry->d_inode)->xattr_sem); |
eaeef867 TT |
490 | ret = ret2 = ext4_xattr_ibody_list(dentry, buffer, buffer_size); |
491 | if (ret < 0) | |
492 | goto errout; | |
493 | if (buffer) { | |
494 | buffer += ret; | |
495 | buffer_size -= ret; | |
ac27a0ec | 496 | } |
eaeef867 TT |
497 | ret = ext4_xattr_block_list(dentry, buffer, buffer_size); |
498 | if (ret < 0) | |
499 | goto errout; | |
500 | ret += ret2; | |
501 | errout: | |
431547b3 | 502 | up_read(&EXT4_I(dentry->d_inode)->xattr_sem); |
eaeef867 | 503 | return ret; |
ac27a0ec DK |
504 | } |
505 | ||
506 | /* | |
617ba13b | 507 | * If the EXT4_FEATURE_COMPAT_EXT_ATTR feature of this file system is |
ac27a0ec DK |
508 | * not set, set it. |
509 | */ | |
617ba13b | 510 | static void ext4_xattr_update_super_block(handle_t *handle, |
ac27a0ec DK |
511 | struct super_block *sb) |
512 | { | |
617ba13b | 513 | if (EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_EXT_ATTR)) |
ac27a0ec DK |
514 | return; |
515 | ||
617ba13b | 516 | if (ext4_journal_get_write_access(handle, EXT4_SB(sb)->s_sbh) == 0) { |
ed2908f3 | 517 | EXT4_SET_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_EXT_ATTR); |
a0375156 | 518 | ext4_handle_dirty_super(handle, sb); |
ac27a0ec | 519 | } |
ac27a0ec DK |
520 | } |
521 | ||
522 | /* | |
523 | * Release the xattr block BH: If the reference count is > 1, decrement | |
524 | * it; otherwise free the block. | |
525 | */ | |
526 | static void | |
617ba13b | 527 | ext4_xattr_release_block(handle_t *handle, struct inode *inode, |
ac27a0ec DK |
528 | struct buffer_head *bh) |
529 | { | |
530 | struct mb_cache_entry *ce = NULL; | |
8a2bfdcb | 531 | int error = 0; |
9c191f70 | 532 | struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode); |
ac27a0ec | 533 | |
9c191f70 | 534 | ce = mb_cache_entry_get(ext4_mb_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); |
1231b3a1 | 557 | dquot_free_block(inode, EXT4_C2B(EXT4_SB(inode->i_sb), 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)) { | |
6dd4ee7c KS |
574 | if (!last->e_value_block && last->e_value_size) { |
575 | size_t offs = le16_to_cpu(last->e_value_offs); | |
576 | if (offs < *min_offs) | |
577 | *min_offs = offs; | |
578 | } | |
7b1b2c1b TT |
579 | if (total) |
580 | *total += EXT4_XATTR_LEN(last->e_name_len); | |
6dd4ee7c KS |
581 | } |
582 | return (*min_offs - ((void *)last - base) - sizeof(__u32)); | |
583 | } | |
584 | ||
ac27a0ec | 585 | static int |
617ba13b | 586 | ext4_xattr_set_entry(struct ext4_xattr_info *i, struct ext4_xattr_search *s) |
ac27a0ec | 587 | { |
617ba13b | 588 | struct ext4_xattr_entry *last; |
ac27a0ec DK |
589 | size_t free, min_offs = s->end - s->base, name_len = strlen(i->name); |
590 | ||
591 | /* Compute min_offs and last. */ | |
592 | last = s->first; | |
617ba13b | 593 | for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) { |
ac27a0ec DK |
594 | if (!last->e_value_block && last->e_value_size) { |
595 | size_t offs = le16_to_cpu(last->e_value_offs); | |
596 | if (offs < min_offs) | |
597 | min_offs = offs; | |
598 | } | |
599 | } | |
600 | free = min_offs - ((void *)last - s->base) - sizeof(__u32); | |
601 | if (!s->not_found) { | |
602 | if (!s->here->e_value_block && s->here->e_value_size) { | |
603 | size_t size = le32_to_cpu(s->here->e_value_size); | |
617ba13b | 604 | free += EXT4_XATTR_SIZE(size); |
ac27a0ec | 605 | } |
617ba13b | 606 | free += EXT4_XATTR_LEN(name_len); |
ac27a0ec DK |
607 | } |
608 | if (i->value) { | |
617ba13b MC |
609 | if (free < EXT4_XATTR_SIZE(i->value_len) || |
610 | free < EXT4_XATTR_LEN(name_len) + | |
611 | EXT4_XATTR_SIZE(i->value_len)) | |
ac27a0ec DK |
612 | return -ENOSPC; |
613 | } | |
614 | ||
615 | if (i->value && s->not_found) { | |
616 | /* Insert the new name. */ | |
617ba13b | 617 | size_t size = EXT4_XATTR_LEN(name_len); |
ac27a0ec DK |
618 | size_t rest = (void *)last - (void *)s->here + sizeof(__u32); |
619 | memmove((void *)s->here + size, s->here, rest); | |
620 | memset(s->here, 0, size); | |
621 | s->here->e_name_index = i->name_index; | |
622 | s->here->e_name_len = name_len; | |
623 | memcpy(s->here->e_name, i->name, name_len); | |
624 | } else { | |
625 | if (!s->here->e_value_block && s->here->e_value_size) { | |
626 | void *first_val = s->base + min_offs; | |
627 | size_t offs = le16_to_cpu(s->here->e_value_offs); | |
628 | void *val = s->base + offs; | |
617ba13b | 629 | size_t size = EXT4_XATTR_SIZE( |
ac27a0ec DK |
630 | le32_to_cpu(s->here->e_value_size)); |
631 | ||
617ba13b | 632 | if (i->value && size == EXT4_XATTR_SIZE(i->value_len)) { |
ac27a0ec DK |
633 | /* The old and the new value have the same |
634 | size. Just replace. */ | |
635 | s->here->e_value_size = | |
636 | cpu_to_le32(i->value_len); | |
bd9926e8 TT |
637 | if (i->value == EXT4_ZERO_XATTR_VALUE) { |
638 | memset(val, 0, size); | |
639 | } else { | |
640 | /* Clear pad bytes first. */ | |
641 | memset(val + size - EXT4_XATTR_PAD, 0, | |
642 | EXT4_XATTR_PAD); | |
643 | memcpy(val, i->value, i->value_len); | |
644 | } | |
ac27a0ec DK |
645 | return 0; |
646 | } | |
647 | ||
648 | /* Remove the old value. */ | |
649 | memmove(first_val + size, first_val, val - first_val); | |
650 | memset(first_val, 0, size); | |
651 | s->here->e_value_size = 0; | |
652 | s->here->e_value_offs = 0; | |
653 | min_offs += size; | |
654 | ||
655 | /* Adjust all value offsets. */ | |
656 | last = s->first; | |
657 | while (!IS_LAST_ENTRY(last)) { | |
658 | size_t o = le16_to_cpu(last->e_value_offs); | |
659 | if (!last->e_value_block && | |
660 | last->e_value_size && o < offs) | |
661 | last->e_value_offs = | |
662 | cpu_to_le16(o + size); | |
617ba13b | 663 | last = EXT4_XATTR_NEXT(last); |
ac27a0ec DK |
664 | } |
665 | } | |
666 | if (!i->value) { | |
667 | /* Remove the old name. */ | |
617ba13b | 668 | size_t size = EXT4_XATTR_LEN(name_len); |
ac27a0ec DK |
669 | last = ENTRY((void *)last - size); |
670 | memmove(s->here, (void *)s->here + size, | |
671 | (void *)last - (void *)s->here + sizeof(__u32)); | |
672 | memset(last, 0, size); | |
673 | } | |
674 | } | |
675 | ||
676 | if (i->value) { | |
677 | /* Insert the new value. */ | |
678 | s->here->e_value_size = cpu_to_le32(i->value_len); | |
679 | if (i->value_len) { | |
617ba13b | 680 | size_t size = EXT4_XATTR_SIZE(i->value_len); |
ac27a0ec DK |
681 | void *val = s->base + min_offs - size; |
682 | s->here->e_value_offs = cpu_to_le16(min_offs - size); | |
bd9926e8 TT |
683 | if (i->value == EXT4_ZERO_XATTR_VALUE) { |
684 | memset(val, 0, size); | |
685 | } else { | |
686 | /* Clear the pad bytes first. */ | |
687 | memset(val + size - EXT4_XATTR_PAD, 0, | |
688 | EXT4_XATTR_PAD); | |
689 | memcpy(val, i->value, i->value_len); | |
690 | } | |
ac27a0ec DK |
691 | } |
692 | } | |
693 | return 0; | |
694 | } | |
695 | ||
617ba13b MC |
696 | struct ext4_xattr_block_find { |
697 | struct ext4_xattr_search s; | |
ac27a0ec DK |
698 | struct buffer_head *bh; |
699 | }; | |
700 | ||
701 | static int | |
617ba13b MC |
702 | ext4_xattr_block_find(struct inode *inode, struct ext4_xattr_info *i, |
703 | struct ext4_xattr_block_find *bs) | |
ac27a0ec DK |
704 | { |
705 | struct super_block *sb = inode->i_sb; | |
706 | int error; | |
707 | ||
708 | ea_idebug(inode, "name=%d.%s, value=%p, value_len=%ld", | |
709 | i->name_index, i->name, i->value, (long)i->value_len); | |
710 | ||
617ba13b | 711 | if (EXT4_I(inode)->i_file_acl) { |
ac27a0ec | 712 | /* The inode already has an extended attribute block. */ |
617ba13b | 713 | bs->bh = sb_bread(sb, EXT4_I(inode)->i_file_acl); |
ac27a0ec DK |
714 | error = -EIO; |
715 | if (!bs->bh) | |
716 | goto cleanup; | |
717 | ea_bdebug(bs->bh, "b_count=%d, refcount=%d", | |
718 | atomic_read(&(bs->bh->b_count)), | |
719 | le32_to_cpu(BHDR(bs->bh)->h_refcount)); | |
cc8e94fd | 720 | if (ext4_xattr_check_block(inode, bs->bh)) { |
24676da4 TT |
721 | EXT4_ERROR_INODE(inode, "bad block %llu", |
722 | EXT4_I(inode)->i_file_acl); | |
ac27a0ec DK |
723 | error = -EIO; |
724 | goto cleanup; | |
725 | } | |
726 | /* Find the named attribute. */ | |
727 | bs->s.base = BHDR(bs->bh); | |
728 | bs->s.first = BFIRST(bs->bh); | |
729 | bs->s.end = bs->bh->b_data + bs->bh->b_size; | |
730 | bs->s.here = bs->s.first; | |
617ba13b | 731 | error = ext4_xattr_find_entry(&bs->s.here, i->name_index, |
ac27a0ec DK |
732 | i->name, bs->bh->b_size, 1); |
733 | if (error && error != -ENODATA) | |
734 | goto cleanup; | |
735 | bs->s.not_found = error; | |
736 | } | |
737 | error = 0; | |
738 | ||
739 | cleanup: | |
740 | return error; | |
741 | } | |
742 | ||
743 | static int | |
617ba13b MC |
744 | ext4_xattr_block_set(handle_t *handle, struct inode *inode, |
745 | struct ext4_xattr_info *i, | |
746 | struct ext4_xattr_block_find *bs) | |
ac27a0ec DK |
747 | { |
748 | struct super_block *sb = inode->i_sb; | |
749 | struct buffer_head *new_bh = NULL; | |
617ba13b | 750 | struct ext4_xattr_search *s = &bs->s; |
ac27a0ec | 751 | struct mb_cache_entry *ce = NULL; |
8a2bfdcb | 752 | int error = 0; |
9c191f70 | 753 | struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode); |
ac27a0ec | 754 | |
617ba13b | 755 | #define header(x) ((struct ext4_xattr_header *)(x)) |
ac27a0ec DK |
756 | |
757 | if (i->value && i->value_len > sb->s_blocksize) | |
758 | return -ENOSPC; | |
759 | if (s->base) { | |
9c191f70 | 760 | ce = mb_cache_entry_get(ext4_mb_cache, bs->bh->b_bdev, |
ac27a0ec | 761 | bs->bh->b_blocknr); |
8a2bfdcb MC |
762 | error = ext4_journal_get_write_access(handle, bs->bh); |
763 | if (error) | |
764 | goto cleanup; | |
765 | lock_buffer(bs->bh); | |
766 | ||
ac27a0ec DK |
767 | if (header(s->base)->h_refcount == cpu_to_le32(1)) { |
768 | if (ce) { | |
769 | mb_cache_entry_free(ce); | |
770 | ce = NULL; | |
771 | } | |
772 | ea_bdebug(bs->bh, "modifying in-place"); | |
617ba13b | 773 | error = ext4_xattr_set_entry(i, s); |
ac27a0ec DK |
774 | if (!error) { |
775 | if (!IS_LAST_ENTRY(s->first)) | |
617ba13b | 776 | ext4_xattr_rehash(header(s->base), |
ac27a0ec | 777 | s->here); |
9c191f70 M |
778 | ext4_xattr_cache_insert(ext4_mb_cache, |
779 | bs->bh); | |
ac27a0ec DK |
780 | } |
781 | unlock_buffer(bs->bh); | |
782 | if (error == -EIO) | |
783 | goto bad_block; | |
784 | if (!error) | |
cc8e94fd DW |
785 | error = ext4_handle_dirty_xattr_block(handle, |
786 | inode, | |
787 | bs->bh); | |
ac27a0ec DK |
788 | if (error) |
789 | goto cleanup; | |
790 | goto inserted; | |
791 | } else { | |
792 | int offset = (char *)s->here - bs->bh->b_data; | |
793 | ||
8a2bfdcb | 794 | unlock_buffer(bs->bh); |
ac27a0ec DK |
795 | if (ce) { |
796 | mb_cache_entry_release(ce); | |
797 | ce = NULL; | |
798 | } | |
799 | ea_bdebug(bs->bh, "cloning"); | |
216553c4 | 800 | s->base = kmalloc(bs->bh->b_size, GFP_NOFS); |
ac27a0ec DK |
801 | error = -ENOMEM; |
802 | if (s->base == NULL) | |
803 | goto cleanup; | |
804 | memcpy(s->base, BHDR(bs->bh), bs->bh->b_size); | |
805 | s->first = ENTRY(header(s->base)+1); | |
806 | header(s->base)->h_refcount = cpu_to_le32(1); | |
807 | s->here = ENTRY(s->base + offset); | |
808 | s->end = s->base + bs->bh->b_size; | |
809 | } | |
810 | } else { | |
811 | /* Allocate a buffer where we construct the new block. */ | |
216553c4 | 812 | s->base = kzalloc(sb->s_blocksize, GFP_NOFS); |
ac27a0ec DK |
813 | /* assert(header == s->base) */ |
814 | error = -ENOMEM; | |
815 | if (s->base == NULL) | |
816 | goto cleanup; | |
617ba13b | 817 | header(s->base)->h_magic = cpu_to_le32(EXT4_XATTR_MAGIC); |
ac27a0ec DK |
818 | header(s->base)->h_blocks = cpu_to_le32(1); |
819 | header(s->base)->h_refcount = cpu_to_le32(1); | |
820 | s->first = ENTRY(header(s->base)+1); | |
821 | s->here = ENTRY(header(s->base)+1); | |
822 | s->end = s->base + sb->s_blocksize; | |
823 | } | |
824 | ||
617ba13b | 825 | error = ext4_xattr_set_entry(i, s); |
ac27a0ec DK |
826 | if (error == -EIO) |
827 | goto bad_block; | |
828 | if (error) | |
829 | goto cleanup; | |
830 | if (!IS_LAST_ENTRY(s->first)) | |
617ba13b | 831 | ext4_xattr_rehash(header(s->base), s->here); |
ac27a0ec DK |
832 | |
833 | inserted: | |
834 | if (!IS_LAST_ENTRY(s->first)) { | |
617ba13b | 835 | new_bh = ext4_xattr_cache_find(inode, header(s->base), &ce); |
ac27a0ec DK |
836 | if (new_bh) { |
837 | /* We found an identical block in the cache. */ | |
838 | if (new_bh == bs->bh) | |
839 | ea_bdebug(new_bh, "keeping"); | |
840 | else { | |
841 | /* The old block is released after updating | |
842 | the inode. */ | |
1231b3a1 LC |
843 | error = dquot_alloc_block(inode, |
844 | EXT4_C2B(EXT4_SB(sb), 1)); | |
5dd4056d | 845 | if (error) |
ac27a0ec | 846 | goto cleanup; |
617ba13b | 847 | error = ext4_journal_get_write_access(handle, |
ac27a0ec DK |
848 | new_bh); |
849 | if (error) | |
850 | goto cleanup_dquot; | |
851 | lock_buffer(new_bh); | |
e8546d06 | 852 | le32_add_cpu(&BHDR(new_bh)->h_refcount, 1); |
ac27a0ec DK |
853 | ea_bdebug(new_bh, "reusing; refcount now=%d", |
854 | le32_to_cpu(BHDR(new_bh)->h_refcount)); | |
855 | unlock_buffer(new_bh); | |
cc8e94fd DW |
856 | error = ext4_handle_dirty_xattr_block(handle, |
857 | inode, | |
858 | new_bh); | |
ac27a0ec DK |
859 | if (error) |
860 | goto cleanup_dquot; | |
861 | } | |
862 | mb_cache_entry_release(ce); | |
863 | ce = NULL; | |
864 | } else if (bs->bh && s->base == bs->bh->b_data) { | |
865 | /* We were modifying this block in-place. */ | |
866 | ea_bdebug(bs->bh, "keeping this block"); | |
867 | new_bh = bs->bh; | |
868 | get_bh(new_bh); | |
869 | } else { | |
870 | /* We need to allocate a new block */ | |
fb0a387d ES |
871 | ext4_fsblk_t goal, block; |
872 | ||
873 | goal = ext4_group_first_block_no(sb, | |
d00a6d7b | 874 | EXT4_I(inode)->i_block_group); |
fb0a387d ES |
875 | |
876 | /* non-extent files can't have physical blocks past 2^32 */ | |
12e9b892 | 877 | if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) |
fb0a387d ES |
878 | goal = goal & EXT4_MAX_BLOCK_FILE_PHYS; |
879 | ||
6d6a4351 ES |
880 | /* |
881 | * take i_data_sem because we will test | |
882 | * i_delalloc_reserved_flag in ext4_mb_new_blocks | |
883 | */ | |
884 | down_read((&EXT4_I(inode)->i_data_sem)); | |
55f020db AH |
885 | block = ext4_new_meta_blocks(handle, inode, goal, 0, |
886 | NULL, &error); | |
6d6a4351 | 887 | up_read((&EXT4_I(inode)->i_data_sem)); |
ac27a0ec DK |
888 | if (error) |
889 | goto cleanup; | |
fb0a387d | 890 | |
12e9b892 | 891 | if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) |
fb0a387d ES |
892 | BUG_ON(block > EXT4_MAX_BLOCK_FILE_PHYS); |
893 | ||
ace36ad4 JP |
894 | ea_idebug(inode, "creating block %llu", |
895 | (unsigned long long)block); | |
ac27a0ec DK |
896 | |
897 | new_bh = sb_getblk(sb, block); | |
aebf0243 | 898 | if (unlikely(!new_bh)) { |
860d21e2 | 899 | error = -ENOMEM; |
ac27a0ec | 900 | getblk_failed: |
7dc57615 | 901 | ext4_free_blocks(handle, inode, NULL, block, 1, |
e6362609 | 902 | EXT4_FREE_BLOCKS_METADATA); |
ac27a0ec DK |
903 | goto cleanup; |
904 | } | |
905 | lock_buffer(new_bh); | |
617ba13b | 906 | error = ext4_journal_get_create_access(handle, new_bh); |
ac27a0ec DK |
907 | if (error) { |
908 | unlock_buffer(new_bh); | |
860d21e2 | 909 | error = -EIO; |
ac27a0ec DK |
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); | |
9c191f70 | 915 | ext4_xattr_cache_insert(ext4_mb_cache, 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: | |
1231b3a1 | 941 | dquot_free_block(inode, EXT4_C2B(EXT4_SB(sb), 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 | ||
879b3825 TM |
952 | int ext4_xattr_ibody_find(struct inode *inode, struct ext4_xattr_info *i, |
953 | struct ext4_xattr_ibody_find *is) | |
ac27a0ec | 954 | { |
617ba13b MC |
955 | struct ext4_xattr_ibody_header *header; |
956 | struct ext4_inode *raw_inode; | |
ac27a0ec DK |
957 | int error; |
958 | ||
617ba13b | 959 | if (EXT4_I(inode)->i_extra_isize == 0) |
ac27a0ec | 960 | return 0; |
617ba13b | 961 | raw_inode = ext4_raw_inode(&is->iloc); |
ac27a0ec DK |
962 | header = IHDR(inode, raw_inode); |
963 | is->s.base = is->s.first = IFIRST(header); | |
964 | is->s.here = is->s.first; | |
617ba13b | 965 | is->s.end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; |
19f5fb7a | 966 | if (ext4_test_inode_state(inode, EXT4_STATE_XATTR)) { |
617ba13b | 967 | error = ext4_xattr_check_names(IFIRST(header), is->s.end); |
ac27a0ec DK |
968 | if (error) |
969 | return error; | |
970 | /* Find the named attribute. */ | |
617ba13b | 971 | error = ext4_xattr_find_entry(&is->s.here, i->name_index, |
ac27a0ec DK |
972 | i->name, is->s.end - |
973 | (void *)is->s.base, 0); | |
974 | if (error && error != -ENODATA) | |
975 | return error; | |
976 | is->s.not_found = error; | |
977 | } | |
978 | return 0; | |
979 | } | |
980 | ||
0d812f77 TM |
981 | int ext4_xattr_ibody_inline_set(handle_t *handle, struct inode *inode, |
982 | struct ext4_xattr_info *i, | |
983 | struct ext4_xattr_ibody_find *is) | |
984 | { | |
985 | struct ext4_xattr_ibody_header *header; | |
986 | struct ext4_xattr_search *s = &is->s; | |
987 | int error; | |
988 | ||
989 | if (EXT4_I(inode)->i_extra_isize == 0) | |
990 | return -ENOSPC; | |
991 | error = ext4_xattr_set_entry(i, s); | |
992 | if (error) { | |
993 | if (error == -ENOSPC && | |
994 | ext4_has_inline_data(inode)) { | |
995 | error = ext4_try_to_evict_inline_data(handle, inode, | |
996 | EXT4_XATTR_LEN(strlen(i->name) + | |
997 | EXT4_XATTR_SIZE(i->value_len))); | |
998 | if (error) | |
999 | return error; | |
1000 | error = ext4_xattr_ibody_find(inode, i, is); | |
1001 | if (error) | |
1002 | return error; | |
1003 | error = ext4_xattr_set_entry(i, s); | |
1004 | } | |
1005 | if (error) | |
1006 | return error; | |
1007 | } | |
1008 | header = IHDR(inode, ext4_raw_inode(&is->iloc)); | |
1009 | if (!IS_LAST_ENTRY(s->first)) { | |
1010 | header->h_magic = cpu_to_le32(EXT4_XATTR_MAGIC); | |
1011 | ext4_set_inode_state(inode, EXT4_STATE_XATTR); | |
1012 | } else { | |
1013 | header->h_magic = cpu_to_le32(0); | |
1014 | ext4_clear_inode_state(inode, EXT4_STATE_XATTR); | |
1015 | } | |
1016 | return 0; | |
1017 | } | |
1018 | ||
1019 | static int ext4_xattr_ibody_set(handle_t *handle, struct inode *inode, | |
1020 | struct ext4_xattr_info *i, | |
1021 | struct ext4_xattr_ibody_find *is) | |
ac27a0ec | 1022 | { |
617ba13b MC |
1023 | struct ext4_xattr_ibody_header *header; |
1024 | struct ext4_xattr_search *s = &is->s; | |
ac27a0ec DK |
1025 | int error; |
1026 | ||
617ba13b | 1027 | if (EXT4_I(inode)->i_extra_isize == 0) |
ac27a0ec | 1028 | return -ENOSPC; |
617ba13b | 1029 | error = ext4_xattr_set_entry(i, s); |
ac27a0ec DK |
1030 | if (error) |
1031 | return error; | |
617ba13b | 1032 | header = IHDR(inode, ext4_raw_inode(&is->iloc)); |
ac27a0ec | 1033 | if (!IS_LAST_ENTRY(s->first)) { |
617ba13b | 1034 | header->h_magic = cpu_to_le32(EXT4_XATTR_MAGIC); |
19f5fb7a | 1035 | ext4_set_inode_state(inode, EXT4_STATE_XATTR); |
ac27a0ec DK |
1036 | } else { |
1037 | header->h_magic = cpu_to_le32(0); | |
19f5fb7a | 1038 | ext4_clear_inode_state(inode, EXT4_STATE_XATTR); |
ac27a0ec DK |
1039 | } |
1040 | return 0; | |
1041 | } | |
1042 | ||
1043 | /* | |
617ba13b | 1044 | * ext4_xattr_set_handle() |
ac27a0ec | 1045 | * |
6e9510b0 | 1046 | * Create, replace or remove an extended attribute for this inode. Value |
ac27a0ec DK |
1047 | * is NULL to remove an existing extended attribute, and non-NULL to |
1048 | * either replace an existing extended attribute, or create a new extended | |
1049 | * attribute. The flags XATTR_REPLACE and XATTR_CREATE | |
1050 | * specify that an extended attribute must exist and must not exist | |
1051 | * previous to the call, respectively. | |
1052 | * | |
1053 | * Returns 0, or a negative error number on failure. | |
1054 | */ | |
1055 | int | |
617ba13b | 1056 | ext4_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index, |
ac27a0ec DK |
1057 | const char *name, const void *value, size_t value_len, |
1058 | int flags) | |
1059 | { | |
617ba13b | 1060 | struct ext4_xattr_info i = { |
ac27a0ec DK |
1061 | .name_index = name_index, |
1062 | .name = name, | |
1063 | .value = value, | |
1064 | .value_len = value_len, | |
1065 | ||
1066 | }; | |
617ba13b | 1067 | struct ext4_xattr_ibody_find is = { |
ac27a0ec DK |
1068 | .s = { .not_found = -ENODATA, }, |
1069 | }; | |
617ba13b | 1070 | struct ext4_xattr_block_find bs = { |
ac27a0ec DK |
1071 | .s = { .not_found = -ENODATA, }, |
1072 | }; | |
4d20c685 | 1073 | unsigned long no_expand; |
ac27a0ec DK |
1074 | int error; |
1075 | ||
1076 | if (!name) | |
1077 | return -EINVAL; | |
1078 | if (strlen(name) > 255) | |
1079 | return -ERANGE; | |
617ba13b | 1080 | down_write(&EXT4_I(inode)->xattr_sem); |
19f5fb7a TT |
1081 | no_expand = ext4_test_inode_state(inode, EXT4_STATE_NO_EXPAND); |
1082 | ext4_set_inode_state(inode, EXT4_STATE_NO_EXPAND); | |
4d20c685 | 1083 | |
66543617 | 1084 | error = ext4_reserve_inode_write(handle, inode, &is.iloc); |
86ebfd08 ES |
1085 | if (error) |
1086 | goto cleanup; | |
1087 | ||
19f5fb7a | 1088 | if (ext4_test_inode_state(inode, EXT4_STATE_NEW)) { |
617ba13b MC |
1089 | struct ext4_inode *raw_inode = ext4_raw_inode(&is.iloc); |
1090 | memset(raw_inode, 0, EXT4_SB(inode->i_sb)->s_inode_size); | |
19f5fb7a | 1091 | ext4_clear_inode_state(inode, EXT4_STATE_NEW); |
ac27a0ec DK |
1092 | } |
1093 | ||
617ba13b | 1094 | error = ext4_xattr_ibody_find(inode, &i, &is); |
ac27a0ec DK |
1095 | if (error) |
1096 | goto cleanup; | |
1097 | if (is.s.not_found) | |
617ba13b | 1098 | error = ext4_xattr_block_find(inode, &i, &bs); |
ac27a0ec DK |
1099 | if (error) |
1100 | goto cleanup; | |
1101 | if (is.s.not_found && bs.s.not_found) { | |
1102 | error = -ENODATA; | |
1103 | if (flags & XATTR_REPLACE) | |
1104 | goto cleanup; | |
1105 | error = 0; | |
1106 | if (!value) | |
1107 | goto cleanup; | |
1108 | } else { | |
1109 | error = -EEXIST; | |
1110 | if (flags & XATTR_CREATE) | |
1111 | goto cleanup; | |
1112 | } | |
ac27a0ec DK |
1113 | if (!value) { |
1114 | if (!is.s.not_found) | |
617ba13b | 1115 | error = ext4_xattr_ibody_set(handle, inode, &i, &is); |
ac27a0ec | 1116 | else if (!bs.s.not_found) |
617ba13b | 1117 | error = ext4_xattr_block_set(handle, inode, &i, &bs); |
ac27a0ec | 1118 | } else { |
617ba13b | 1119 | error = ext4_xattr_ibody_set(handle, inode, &i, &is); |
ac27a0ec DK |
1120 | if (!error && !bs.s.not_found) { |
1121 | i.value = NULL; | |
617ba13b | 1122 | error = ext4_xattr_block_set(handle, inode, &i, &bs); |
ac27a0ec | 1123 | } else if (error == -ENOSPC) { |
7e01c8e5 TY |
1124 | if (EXT4_I(inode)->i_file_acl && !bs.s.base) { |
1125 | error = ext4_xattr_block_find(inode, &i, &bs); | |
1126 | if (error) | |
1127 | goto cleanup; | |
1128 | } | |
617ba13b | 1129 | error = ext4_xattr_block_set(handle, inode, &i, &bs); |
ac27a0ec DK |
1130 | if (error) |
1131 | goto cleanup; | |
1132 | if (!is.s.not_found) { | |
1133 | i.value = NULL; | |
617ba13b | 1134 | error = ext4_xattr_ibody_set(handle, inode, &i, |
ac27a0ec DK |
1135 | &is); |
1136 | } | |
1137 | } | |
1138 | } | |
1139 | if (!error) { | |
617ba13b | 1140 | ext4_xattr_update_super_block(handle, inode->i_sb); |
ef7f3835 | 1141 | inode->i_ctime = ext4_current_time(inode); |
6dd4ee7c | 1142 | if (!value) |
19f5fb7a | 1143 | ext4_clear_inode_state(inode, EXT4_STATE_NO_EXPAND); |
617ba13b | 1144 | error = ext4_mark_iloc_dirty(handle, inode, &is.iloc); |
ac27a0ec | 1145 | /* |
617ba13b | 1146 | * The bh is consumed by ext4_mark_iloc_dirty, even with |
ac27a0ec DK |
1147 | * error != 0. |
1148 | */ | |
1149 | is.iloc.bh = NULL; | |
1150 | if (IS_SYNC(inode)) | |
0390131b | 1151 | ext4_handle_sync(handle); |
ac27a0ec DK |
1152 | } |
1153 | ||
1154 | cleanup: | |
1155 | brelse(is.iloc.bh); | |
1156 | brelse(bs.bh); | |
4d20c685 | 1157 | if (no_expand == 0) |
19f5fb7a | 1158 | ext4_clear_inode_state(inode, EXT4_STATE_NO_EXPAND); |
617ba13b | 1159 | up_write(&EXT4_I(inode)->xattr_sem); |
ac27a0ec DK |
1160 | return error; |
1161 | } | |
1162 | ||
1163 | /* | |
617ba13b | 1164 | * ext4_xattr_set() |
ac27a0ec | 1165 | * |
617ba13b | 1166 | * Like ext4_xattr_set_handle, but start from an inode. This extended |
ac27a0ec DK |
1167 | * attribute modification is a filesystem transaction by itself. |
1168 | * | |
1169 | * Returns 0, or a negative error number on failure. | |
1170 | */ | |
1171 | int | |
617ba13b | 1172 | ext4_xattr_set(struct inode *inode, int name_index, const char *name, |
ac27a0ec DK |
1173 | const void *value, size_t value_len, int flags) |
1174 | { | |
1175 | handle_t *handle; | |
1176 | int error, retries = 0; | |
95eaefbd | 1177 | int credits = ext4_jbd2_credits_xattr(inode); |
ac27a0ec DK |
1178 | |
1179 | retry: | |
9924a92a | 1180 | handle = ext4_journal_start(inode, EXT4_HT_XATTR, credits); |
ac27a0ec DK |
1181 | if (IS_ERR(handle)) { |
1182 | error = PTR_ERR(handle); | |
1183 | } else { | |
1184 | int error2; | |
1185 | ||
617ba13b | 1186 | error = ext4_xattr_set_handle(handle, inode, name_index, name, |
ac27a0ec | 1187 | value, value_len, flags); |
617ba13b | 1188 | error2 = ext4_journal_stop(handle); |
ac27a0ec | 1189 | if (error == -ENOSPC && |
617ba13b | 1190 | ext4_should_retry_alloc(inode->i_sb, &retries)) |
ac27a0ec DK |
1191 | goto retry; |
1192 | if (error == 0) | |
1193 | error = error2; | |
1194 | } | |
1195 | ||
1196 | return error; | |
1197 | } | |
1198 | ||
6dd4ee7c KS |
1199 | /* |
1200 | * Shift the EA entries in the inode to create space for the increased | |
1201 | * i_extra_isize. | |
1202 | */ | |
1203 | static void ext4_xattr_shift_entries(struct ext4_xattr_entry *entry, | |
1204 | int value_offs_shift, void *to, | |
1205 | void *from, size_t n, int blocksize) | |
1206 | { | |
1207 | struct ext4_xattr_entry *last = entry; | |
1208 | int new_offs; | |
1209 | ||
1210 | /* Adjust the value offsets of the entries */ | |
1211 | for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) { | |
1212 | if (!last->e_value_block && last->e_value_size) { | |
1213 | new_offs = le16_to_cpu(last->e_value_offs) + | |
1214 | value_offs_shift; | |
1215 | BUG_ON(new_offs + le32_to_cpu(last->e_value_size) | |
1216 | > blocksize); | |
1217 | last->e_value_offs = cpu_to_le16(new_offs); | |
1218 | } | |
1219 | } | |
1220 | /* Shift the entries by n bytes */ | |
1221 | memmove(to, from, n); | |
1222 | } | |
1223 | ||
1224 | /* | |
1225 | * Expand an inode by new_extra_isize bytes when EAs are present. | |
1226 | * Returns 0 on success or negative error number on failure. | |
1227 | */ | |
1228 | int ext4_expand_extra_isize_ea(struct inode *inode, int new_extra_isize, | |
1229 | struct ext4_inode *raw_inode, handle_t *handle) | |
1230 | { | |
1231 | struct ext4_xattr_ibody_header *header; | |
1232 | struct ext4_xattr_entry *entry, *last, *first; | |
1233 | struct buffer_head *bh = NULL; | |
1234 | struct ext4_xattr_ibody_find *is = NULL; | |
1235 | struct ext4_xattr_block_find *bs = NULL; | |
1236 | char *buffer = NULL, *b_entry_name = NULL; | |
1237 | size_t min_offs, free; | |
7b1b2c1b | 1238 | int total_ino; |
6dd4ee7c KS |
1239 | void *base, *start, *end; |
1240 | int extra_isize = 0, error = 0, tried_min_extra_isize = 0; | |
ac39849d | 1241 | int s_min_extra_isize = le16_to_cpu(EXT4_SB(inode->i_sb)->s_es->s_min_extra_isize); |
6dd4ee7c KS |
1242 | |
1243 | down_write(&EXT4_I(inode)->xattr_sem); | |
1244 | retry: | |
1245 | if (EXT4_I(inode)->i_extra_isize >= new_extra_isize) { | |
1246 | up_write(&EXT4_I(inode)->xattr_sem); | |
1247 | return 0; | |
1248 | } | |
1249 | ||
1250 | header = IHDR(inode, raw_inode); | |
1251 | entry = IFIRST(header); | |
1252 | ||
1253 | /* | |
1254 | * Check if enough free space is available in the inode to shift the | |
1255 | * entries ahead by new_extra_isize. | |
1256 | */ | |
1257 | ||
1258 | base = start = entry; | |
1259 | end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; | |
1260 | min_offs = end - base; | |
1261 | last = entry; | |
1262 | total_ino = sizeof(struct ext4_xattr_ibody_header); | |
1263 | ||
1264 | free = ext4_xattr_free_space(last, &min_offs, base, &total_ino); | |
1265 | if (free >= new_extra_isize) { | |
1266 | entry = IFIRST(header); | |
1267 | ext4_xattr_shift_entries(entry, EXT4_I(inode)->i_extra_isize | |
1268 | - new_extra_isize, (void *)raw_inode + | |
1269 | EXT4_GOOD_OLD_INODE_SIZE + new_extra_isize, | |
1270 | (void *)header, total_ino, | |
1271 | inode->i_sb->s_blocksize); | |
1272 | EXT4_I(inode)->i_extra_isize = new_extra_isize; | |
1273 | error = 0; | |
1274 | goto cleanup; | |
1275 | } | |
1276 | ||
1277 | /* | |
1278 | * Enough free space isn't available in the inode, check if | |
1279 | * EA block can hold new_extra_isize bytes. | |
1280 | */ | |
1281 | if (EXT4_I(inode)->i_file_acl) { | |
1282 | bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl); | |
1283 | error = -EIO; | |
1284 | if (!bh) | |
1285 | goto cleanup; | |
cc8e94fd | 1286 | if (ext4_xattr_check_block(inode, bh)) { |
24676da4 TT |
1287 | EXT4_ERROR_INODE(inode, "bad block %llu", |
1288 | EXT4_I(inode)->i_file_acl); | |
6dd4ee7c KS |
1289 | error = -EIO; |
1290 | goto cleanup; | |
1291 | } | |
1292 | base = BHDR(bh); | |
1293 | first = BFIRST(bh); | |
1294 | end = bh->b_data + bh->b_size; | |
1295 | min_offs = end - base; | |
7b1b2c1b | 1296 | free = ext4_xattr_free_space(first, &min_offs, base, NULL); |
6dd4ee7c KS |
1297 | if (free < new_extra_isize) { |
1298 | if (!tried_min_extra_isize && s_min_extra_isize) { | |
1299 | tried_min_extra_isize++; | |
1300 | new_extra_isize = s_min_extra_isize; | |
1301 | brelse(bh); | |
1302 | goto retry; | |
1303 | } | |
1304 | error = -1; | |
1305 | goto cleanup; | |
1306 | } | |
1307 | } else { | |
1308 | free = inode->i_sb->s_blocksize; | |
1309 | } | |
1310 | ||
1311 | while (new_extra_isize > 0) { | |
1312 | size_t offs, size, entry_size; | |
1313 | struct ext4_xattr_entry *small_entry = NULL; | |
1314 | struct ext4_xattr_info i = { | |
1315 | .value = NULL, | |
1316 | .value_len = 0, | |
1317 | }; | |
1318 | unsigned int total_size; /* EA entry size + value size */ | |
1319 | unsigned int shift_bytes; /* No. of bytes to shift EAs by? */ | |
1320 | unsigned int min_total_size = ~0U; | |
1321 | ||
1322 | is = kzalloc(sizeof(struct ext4_xattr_ibody_find), GFP_NOFS); | |
1323 | bs = kzalloc(sizeof(struct ext4_xattr_block_find), GFP_NOFS); | |
1324 | if (!is || !bs) { | |
1325 | error = -ENOMEM; | |
1326 | goto cleanup; | |
1327 | } | |
1328 | ||
1329 | is->s.not_found = -ENODATA; | |
1330 | bs->s.not_found = -ENODATA; | |
1331 | is->iloc.bh = NULL; | |
1332 | bs->bh = NULL; | |
1333 | ||
1334 | last = IFIRST(header); | |
1335 | /* Find the entry best suited to be pushed into EA block */ | |
1336 | entry = NULL; | |
1337 | for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) { | |
1338 | total_size = | |
1339 | EXT4_XATTR_SIZE(le32_to_cpu(last->e_value_size)) + | |
1340 | EXT4_XATTR_LEN(last->e_name_len); | |
1341 | if (total_size <= free && total_size < min_total_size) { | |
1342 | if (total_size < new_extra_isize) { | |
1343 | small_entry = last; | |
1344 | } else { | |
1345 | entry = last; | |
1346 | min_total_size = total_size; | |
1347 | } | |
1348 | } | |
1349 | } | |
1350 | ||
1351 | if (entry == NULL) { | |
1352 | if (small_entry) { | |
1353 | entry = small_entry; | |
1354 | } else { | |
1355 | if (!tried_min_extra_isize && | |
1356 | s_min_extra_isize) { | |
1357 | tried_min_extra_isize++; | |
1358 | new_extra_isize = s_min_extra_isize; | |
6e4ea8e3 DJ |
1359 | kfree(is); is = NULL; |
1360 | kfree(bs); bs = NULL; | |
dcb9917b | 1361 | brelse(bh); |
6dd4ee7c KS |
1362 | goto retry; |
1363 | } | |
1364 | error = -1; | |
1365 | goto cleanup; | |
1366 | } | |
1367 | } | |
1368 | offs = le16_to_cpu(entry->e_value_offs); | |
1369 | size = le32_to_cpu(entry->e_value_size); | |
1370 | entry_size = EXT4_XATTR_LEN(entry->e_name_len); | |
1371 | i.name_index = entry->e_name_index, | |
1372 | buffer = kmalloc(EXT4_XATTR_SIZE(size), GFP_NOFS); | |
1373 | b_entry_name = kmalloc(entry->e_name_len + 1, GFP_NOFS); | |
1374 | if (!buffer || !b_entry_name) { | |
1375 | error = -ENOMEM; | |
1376 | goto cleanup; | |
1377 | } | |
1378 | /* Save the entry name and the entry value */ | |
1379 | memcpy(buffer, (void *)IFIRST(header) + offs, | |
1380 | EXT4_XATTR_SIZE(size)); | |
1381 | memcpy(b_entry_name, entry->e_name, entry->e_name_len); | |
1382 | b_entry_name[entry->e_name_len] = '\0'; | |
1383 | i.name = b_entry_name; | |
1384 | ||
1385 | error = ext4_get_inode_loc(inode, &is->iloc); | |
1386 | if (error) | |
1387 | goto cleanup; | |
1388 | ||
1389 | error = ext4_xattr_ibody_find(inode, &i, is); | |
1390 | if (error) | |
1391 | goto cleanup; | |
1392 | ||
1393 | /* Remove the chosen entry from the inode */ | |
1394 | error = ext4_xattr_ibody_set(handle, inode, &i, is); | |
9aaab058 RK |
1395 | if (error) |
1396 | goto cleanup; | |
6dd4ee7c KS |
1397 | |
1398 | entry = IFIRST(header); | |
1399 | if (entry_size + EXT4_XATTR_SIZE(size) >= new_extra_isize) | |
1400 | shift_bytes = new_extra_isize; | |
1401 | else | |
1402 | shift_bytes = entry_size + size; | |
1403 | /* Adjust the offsets and shift the remaining entries ahead */ | |
1404 | ext4_xattr_shift_entries(entry, EXT4_I(inode)->i_extra_isize - | |
1405 | shift_bytes, (void *)raw_inode + | |
1406 | EXT4_GOOD_OLD_INODE_SIZE + extra_isize + shift_bytes, | |
1407 | (void *)header, total_ino - entry_size, | |
1408 | inode->i_sb->s_blocksize); | |
1409 | ||
1410 | extra_isize += shift_bytes; | |
1411 | new_extra_isize -= shift_bytes; | |
1412 | EXT4_I(inode)->i_extra_isize = extra_isize; | |
1413 | ||
1414 | i.name = b_entry_name; | |
1415 | i.value = buffer; | |
ac39849d | 1416 | i.value_len = size; |
6dd4ee7c KS |
1417 | error = ext4_xattr_block_find(inode, &i, bs); |
1418 | if (error) | |
1419 | goto cleanup; | |
1420 | ||
1421 | /* Add entry which was removed from the inode into the block */ | |
1422 | error = ext4_xattr_block_set(handle, inode, &i, bs); | |
1423 | if (error) | |
1424 | goto cleanup; | |
1425 | kfree(b_entry_name); | |
1426 | kfree(buffer); | |
d3533d72 JL |
1427 | b_entry_name = NULL; |
1428 | buffer = NULL; | |
6dd4ee7c KS |
1429 | brelse(is->iloc.bh); |
1430 | kfree(is); | |
1431 | kfree(bs); | |
1432 | } | |
1433 | brelse(bh); | |
1434 | up_write(&EXT4_I(inode)->xattr_sem); | |
1435 | return 0; | |
1436 | ||
1437 | cleanup: | |
1438 | kfree(b_entry_name); | |
1439 | kfree(buffer); | |
1440 | if (is) | |
1441 | brelse(is->iloc.bh); | |
1442 | kfree(is); | |
1443 | kfree(bs); | |
1444 | brelse(bh); | |
1445 | up_write(&EXT4_I(inode)->xattr_sem); | |
1446 | return error; | |
1447 | } | |
1448 | ||
1449 | ||
1450 | ||
ac27a0ec | 1451 | /* |
617ba13b | 1452 | * ext4_xattr_delete_inode() |
ac27a0ec DK |
1453 | * |
1454 | * Free extended attribute resources associated with this inode. This | |
1455 | * is called immediately before an inode is freed. We have exclusive | |
1456 | * access to the inode. | |
1457 | */ | |
1458 | void | |
617ba13b | 1459 | ext4_xattr_delete_inode(handle_t *handle, struct inode *inode) |
ac27a0ec DK |
1460 | { |
1461 | struct buffer_head *bh = NULL; | |
1462 | ||
617ba13b | 1463 | if (!EXT4_I(inode)->i_file_acl) |
ac27a0ec | 1464 | goto cleanup; |
617ba13b | 1465 | bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl); |
ac27a0ec | 1466 | if (!bh) { |
24676da4 TT |
1467 | EXT4_ERROR_INODE(inode, "block %llu read error", |
1468 | EXT4_I(inode)->i_file_acl); | |
ac27a0ec DK |
1469 | goto cleanup; |
1470 | } | |
617ba13b | 1471 | if (BHDR(bh)->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC) || |
ac27a0ec | 1472 | BHDR(bh)->h_blocks != cpu_to_le32(1)) { |
24676da4 TT |
1473 | EXT4_ERROR_INODE(inode, "bad block %llu", |
1474 | EXT4_I(inode)->i_file_acl); | |
ac27a0ec DK |
1475 | goto cleanup; |
1476 | } | |
617ba13b MC |
1477 | ext4_xattr_release_block(handle, inode, bh); |
1478 | EXT4_I(inode)->i_file_acl = 0; | |
ac27a0ec DK |
1479 | |
1480 | cleanup: | |
1481 | brelse(bh); | |
1482 | } | |
1483 | ||
1484 | /* | |
617ba13b | 1485 | * ext4_xattr_put_super() |
ac27a0ec DK |
1486 | * |
1487 | * This is called when a file system is unmounted. | |
1488 | */ | |
1489 | void | |
617ba13b | 1490 | ext4_xattr_put_super(struct super_block *sb) |
ac27a0ec DK |
1491 | { |
1492 | mb_cache_shrink(sb->s_bdev); | |
1493 | } | |
1494 | ||
1495 | /* | |
617ba13b | 1496 | * ext4_xattr_cache_insert() |
ac27a0ec DK |
1497 | * |
1498 | * Create a new entry in the extended attribute cache, and insert | |
1499 | * it unless such an entry is already in the cache. | |
1500 | * | |
1501 | * Returns 0, or a negative error number on failure. | |
1502 | */ | |
1503 | static void | |
9c191f70 | 1504 | ext4_xattr_cache_insert(struct mb_cache *ext4_mb_cache, struct buffer_head *bh) |
ac27a0ec DK |
1505 | { |
1506 | __u32 hash = le32_to_cpu(BHDR(bh)->h_hash); | |
1507 | struct mb_cache_entry *ce; | |
1508 | int error; | |
1509 | ||
9c191f70 | 1510 | ce = mb_cache_entry_alloc(ext4_mb_cache, GFP_NOFS); |
ac27a0ec DK |
1511 | if (!ce) { |
1512 | ea_bdebug(bh, "out of memory"); | |
1513 | return; | |
1514 | } | |
2aec7c52 | 1515 | error = mb_cache_entry_insert(ce, bh->b_bdev, bh->b_blocknr, hash); |
ac27a0ec DK |
1516 | if (error) { |
1517 | mb_cache_entry_free(ce); | |
1518 | if (error == -EBUSY) { | |
1519 | ea_bdebug(bh, "already in cache"); | |
1520 | error = 0; | |
1521 | } | |
1522 | } else { | |
1523 | ea_bdebug(bh, "inserting [%x]", (int)hash); | |
1524 | mb_cache_entry_release(ce); | |
1525 | } | |
1526 | } | |
1527 | ||
1528 | /* | |
617ba13b | 1529 | * ext4_xattr_cmp() |
ac27a0ec DK |
1530 | * |
1531 | * Compare two extended attribute blocks for equality. | |
1532 | * | |
1533 | * Returns 0 if the blocks are equal, 1 if they differ, and | |
1534 | * a negative error number on errors. | |
1535 | */ | |
1536 | static int | |
617ba13b MC |
1537 | ext4_xattr_cmp(struct ext4_xattr_header *header1, |
1538 | struct ext4_xattr_header *header2) | |
ac27a0ec | 1539 | { |
617ba13b | 1540 | struct ext4_xattr_entry *entry1, *entry2; |
ac27a0ec DK |
1541 | |
1542 | entry1 = ENTRY(header1+1); | |
1543 | entry2 = ENTRY(header2+1); | |
1544 | while (!IS_LAST_ENTRY(entry1)) { | |
1545 | if (IS_LAST_ENTRY(entry2)) | |
1546 | return 1; | |
1547 | if (entry1->e_hash != entry2->e_hash || | |
1548 | entry1->e_name_index != entry2->e_name_index || | |
1549 | entry1->e_name_len != entry2->e_name_len || | |
1550 | entry1->e_value_size != entry2->e_value_size || | |
1551 | memcmp(entry1->e_name, entry2->e_name, entry1->e_name_len)) | |
1552 | return 1; | |
1553 | if (entry1->e_value_block != 0 || entry2->e_value_block != 0) | |
1554 | return -EIO; | |
1555 | if (memcmp((char *)header1 + le16_to_cpu(entry1->e_value_offs), | |
1556 | (char *)header2 + le16_to_cpu(entry2->e_value_offs), | |
1557 | le32_to_cpu(entry1->e_value_size))) | |
1558 | return 1; | |
1559 | ||
617ba13b MC |
1560 | entry1 = EXT4_XATTR_NEXT(entry1); |
1561 | entry2 = EXT4_XATTR_NEXT(entry2); | |
ac27a0ec DK |
1562 | } |
1563 | if (!IS_LAST_ENTRY(entry2)) | |
1564 | return 1; | |
1565 | return 0; | |
1566 | } | |
1567 | ||
1568 | /* | |
617ba13b | 1569 | * ext4_xattr_cache_find() |
ac27a0ec DK |
1570 | * |
1571 | * Find an identical extended attribute block. | |
1572 | * | |
1573 | * Returns a pointer to the block found, or NULL if such a block was | |
1574 | * not found or an error occurred. | |
1575 | */ | |
1576 | static struct buffer_head * | |
617ba13b | 1577 | ext4_xattr_cache_find(struct inode *inode, struct ext4_xattr_header *header, |
ac27a0ec DK |
1578 | struct mb_cache_entry **pce) |
1579 | { | |
1580 | __u32 hash = le32_to_cpu(header->h_hash); | |
1581 | struct mb_cache_entry *ce; | |
9c191f70 | 1582 | struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode); |
ac27a0ec DK |
1583 | |
1584 | if (!header->h_hash) | |
1585 | return NULL; /* never share */ | |
1586 | ea_idebug(inode, "looking for cached blocks [%x]", (int)hash); | |
1587 | again: | |
9c191f70 | 1588 | ce = mb_cache_entry_find_first(ext4_mb_cache, inode->i_sb->s_bdev, |
2aec7c52 | 1589 | hash); |
ac27a0ec DK |
1590 | while (ce) { |
1591 | struct buffer_head *bh; | |
1592 | ||
1593 | if (IS_ERR(ce)) { | |
1594 | if (PTR_ERR(ce) == -EAGAIN) | |
1595 | goto again; | |
1596 | break; | |
1597 | } | |
1598 | bh = sb_bread(inode->i_sb, ce->e_block); | |
1599 | if (!bh) { | |
24676da4 TT |
1600 | EXT4_ERROR_INODE(inode, "block %lu read error", |
1601 | (unsigned long) ce->e_block); | |
ac27a0ec | 1602 | } else if (le32_to_cpu(BHDR(bh)->h_refcount) >= |
617ba13b | 1603 | EXT4_XATTR_REFCOUNT_MAX) { |
ac27a0ec DK |
1604 | ea_idebug(inode, "block %lu refcount %d>=%d", |
1605 | (unsigned long) ce->e_block, | |
1606 | le32_to_cpu(BHDR(bh)->h_refcount), | |
617ba13b MC |
1607 | EXT4_XATTR_REFCOUNT_MAX); |
1608 | } else if (ext4_xattr_cmp(header, BHDR(bh)) == 0) { | |
ac27a0ec DK |
1609 | *pce = ce; |
1610 | return bh; | |
1611 | } | |
1612 | brelse(bh); | |
2aec7c52 | 1613 | ce = mb_cache_entry_find_next(ce, inode->i_sb->s_bdev, hash); |
ac27a0ec DK |
1614 | } |
1615 | return NULL; | |
1616 | } | |
1617 | ||
1618 | #define NAME_HASH_SHIFT 5 | |
1619 | #define VALUE_HASH_SHIFT 16 | |
1620 | ||
1621 | /* | |
617ba13b | 1622 | * ext4_xattr_hash_entry() |
ac27a0ec DK |
1623 | * |
1624 | * Compute the hash of an extended attribute. | |
1625 | */ | |
617ba13b MC |
1626 | static inline void ext4_xattr_hash_entry(struct ext4_xattr_header *header, |
1627 | struct ext4_xattr_entry *entry) | |
ac27a0ec DK |
1628 | { |
1629 | __u32 hash = 0; | |
1630 | char *name = entry->e_name; | |
1631 | int n; | |
1632 | ||
2b2d6d01 | 1633 | for (n = 0; n < entry->e_name_len; n++) { |
ac27a0ec DK |
1634 | hash = (hash << NAME_HASH_SHIFT) ^ |
1635 | (hash >> (8*sizeof(hash) - NAME_HASH_SHIFT)) ^ | |
1636 | *name++; | |
1637 | } | |
1638 | ||
1639 | if (entry->e_value_block == 0 && entry->e_value_size != 0) { | |
1640 | __le32 *value = (__le32 *)((char *)header + | |
1641 | le16_to_cpu(entry->e_value_offs)); | |
1642 | for (n = (le32_to_cpu(entry->e_value_size) + | |
617ba13b | 1643 | EXT4_XATTR_ROUND) >> EXT4_XATTR_PAD_BITS; n; n--) { |
ac27a0ec DK |
1644 | hash = (hash << VALUE_HASH_SHIFT) ^ |
1645 | (hash >> (8*sizeof(hash) - VALUE_HASH_SHIFT)) ^ | |
1646 | le32_to_cpu(*value++); | |
1647 | } | |
1648 | } | |
1649 | entry->e_hash = cpu_to_le32(hash); | |
1650 | } | |
1651 | ||
1652 | #undef NAME_HASH_SHIFT | |
1653 | #undef VALUE_HASH_SHIFT | |
1654 | ||
1655 | #define BLOCK_HASH_SHIFT 16 | |
1656 | ||
1657 | /* | |
617ba13b | 1658 | * ext4_xattr_rehash() |
ac27a0ec DK |
1659 | * |
1660 | * Re-compute the extended attribute hash value after an entry has changed. | |
1661 | */ | |
617ba13b MC |
1662 | static void ext4_xattr_rehash(struct ext4_xattr_header *header, |
1663 | struct ext4_xattr_entry *entry) | |
ac27a0ec | 1664 | { |
617ba13b | 1665 | struct ext4_xattr_entry *here; |
ac27a0ec DK |
1666 | __u32 hash = 0; |
1667 | ||
617ba13b | 1668 | ext4_xattr_hash_entry(header, entry); |
ac27a0ec DK |
1669 | here = ENTRY(header+1); |
1670 | while (!IS_LAST_ENTRY(here)) { | |
1671 | if (!here->e_hash) { | |
1672 | /* Block is not shared if an entry's hash value == 0 */ | |
1673 | hash = 0; | |
1674 | break; | |
1675 | } | |
1676 | hash = (hash << BLOCK_HASH_SHIFT) ^ | |
1677 | (hash >> (8*sizeof(hash) - BLOCK_HASH_SHIFT)) ^ | |
1678 | le32_to_cpu(here->e_hash); | |
617ba13b | 1679 | here = EXT4_XATTR_NEXT(here); |
ac27a0ec DK |
1680 | } |
1681 | header->h_hash = cpu_to_le32(hash); | |
1682 | } | |
1683 | ||
1684 | #undef BLOCK_HASH_SHIFT | |
1685 | ||
9c191f70 M |
1686 | #define HASH_BUCKET_BITS 10 |
1687 | ||
1688 | struct mb_cache * | |
1689 | ext4_xattr_create_cache(char *name) | |
ac27a0ec | 1690 | { |
9c191f70 | 1691 | return mb_cache_create(name, HASH_BUCKET_BITS); |
ac27a0ec DK |
1692 | } |
1693 | ||
9c191f70 | 1694 | void ext4_xattr_destroy_cache(struct mb_cache *cache) |
ac27a0ec | 1695 | { |
9c191f70 M |
1696 | if (cache) |
1697 | mb_cache_destroy(cache); | |
ac27a0ec | 1698 | } |
9c191f70 | 1699 |