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Commit | Line | Data |
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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> | |
7a2508e1 | 56 | #include <linux/mbcache.h> |
ac27a0ec | 57 | #include <linux/quotaops.h> |
3dcf5451 CH |
58 | #include "ext4_jbd2.h" |
59 | #include "ext4.h" | |
ac27a0ec DK |
60 | #include "xattr.h" |
61 | #include "acl.h" | |
62 | ||
617ba13b | 63 | #ifdef EXT4_XATTR_DEBUG |
ac27a0ec DK |
64 | # define ea_idebug(inode, f...) do { \ |
65 | printk(KERN_DEBUG "inode %s:%lu: ", \ | |
66 | inode->i_sb->s_id, inode->i_ino); \ | |
67 | printk(f); \ | |
68 | printk("\n"); \ | |
69 | } while (0) | |
70 | # define ea_bdebug(bh, f...) do { \ | |
a1c6f057 DM |
71 | printk(KERN_DEBUG "block %pg:%lu: ", \ |
72 | bh->b_bdev, (unsigned long) bh->b_blocknr); \ | |
ac27a0ec DK |
73 | printk(f); \ |
74 | printk("\n"); \ | |
75 | } while (0) | |
76 | #else | |
ace36ad4 JP |
77 | # define ea_idebug(inode, fmt, ...) no_printk(fmt, ##__VA_ARGS__) |
78 | # define ea_bdebug(bh, fmt, ...) no_printk(fmt, ##__VA_ARGS__) | |
ac27a0ec DK |
79 | #endif |
80 | ||
7a2508e1 | 81 | static void ext4_xattr_cache_insert(struct mb_cache *, struct buffer_head *); |
617ba13b MC |
82 | static struct buffer_head *ext4_xattr_cache_find(struct inode *, |
83 | struct ext4_xattr_header *, | |
7a2508e1 | 84 | struct mb_cache_entry **); |
617ba13b MC |
85 | static void ext4_xattr_rehash(struct ext4_xattr_header *, |
86 | struct ext4_xattr_entry *); | |
431547b3 | 87 | static int ext4_xattr_list(struct dentry *dentry, char *buffer, |
d3a95d47 | 88 | size_t buffer_size); |
ac27a0ec | 89 | |
11e27528 | 90 | static const struct xattr_handler *ext4_xattr_handler_map[] = { |
617ba13b | 91 | [EXT4_XATTR_INDEX_USER] = &ext4_xattr_user_handler, |
03010a33 | 92 | #ifdef CONFIG_EXT4_FS_POSIX_ACL |
64e178a7 CH |
93 | [EXT4_XATTR_INDEX_POSIX_ACL_ACCESS] = &posix_acl_access_xattr_handler, |
94 | [EXT4_XATTR_INDEX_POSIX_ACL_DEFAULT] = &posix_acl_default_xattr_handler, | |
ac27a0ec | 95 | #endif |
617ba13b | 96 | [EXT4_XATTR_INDEX_TRUSTED] = &ext4_xattr_trusted_handler, |
03010a33 | 97 | #ifdef CONFIG_EXT4_FS_SECURITY |
617ba13b | 98 | [EXT4_XATTR_INDEX_SECURITY] = &ext4_xattr_security_handler, |
ac27a0ec DK |
99 | #endif |
100 | }; | |
101 | ||
11e27528 | 102 | const struct xattr_handler *ext4_xattr_handlers[] = { |
617ba13b MC |
103 | &ext4_xattr_user_handler, |
104 | &ext4_xattr_trusted_handler, | |
03010a33 | 105 | #ifdef CONFIG_EXT4_FS_POSIX_ACL |
64e178a7 CH |
106 | &posix_acl_access_xattr_handler, |
107 | &posix_acl_default_xattr_handler, | |
ac27a0ec | 108 | #endif |
03010a33 | 109 | #ifdef CONFIG_EXT4_FS_SECURITY |
617ba13b | 110 | &ext4_xattr_security_handler, |
ac27a0ec DK |
111 | #endif |
112 | NULL | |
113 | }; | |
114 | ||
9c191f70 M |
115 | #define EXT4_GET_MB_CACHE(inode) (((struct ext4_sb_info *) \ |
116 | inode->i_sb->s_fs_info)->s_mb_cache) | |
117 | ||
cc8e94fd DW |
118 | static __le32 ext4_xattr_block_csum(struct inode *inode, |
119 | sector_t block_nr, | |
120 | struct ext4_xattr_header *hdr) | |
121 | { | |
122 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); | |
d6a77105 | 123 | __u32 csum; |
d6a77105 | 124 | __le64 dsk_block_nr = cpu_to_le64(block_nr); |
b47820ed DJ |
125 | __u32 dummy_csum = 0; |
126 | int offset = offsetof(struct ext4_xattr_header, h_checksum); | |
cc8e94fd | 127 | |
d6a77105 TT |
128 | csum = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&dsk_block_nr, |
129 | sizeof(dsk_block_nr)); | |
b47820ed DJ |
130 | csum = ext4_chksum(sbi, csum, (__u8 *)hdr, offset); |
131 | csum = ext4_chksum(sbi, csum, (__u8 *)&dummy_csum, sizeof(dummy_csum)); | |
132 | offset += sizeof(dummy_csum); | |
133 | csum = ext4_chksum(sbi, csum, (__u8 *)hdr + offset, | |
134 | EXT4_BLOCK_SIZE(inode->i_sb) - offset); | |
41eb70dd | 135 | |
cc8e94fd DW |
136 | return cpu_to_le32(csum); |
137 | } | |
138 | ||
139 | static int ext4_xattr_block_csum_verify(struct inode *inode, | |
140 | sector_t block_nr, | |
141 | struct ext4_xattr_header *hdr) | |
142 | { | |
9aa5d32b | 143 | if (ext4_has_metadata_csum(inode->i_sb) && |
cc8e94fd DW |
144 | (hdr->h_checksum != ext4_xattr_block_csum(inode, block_nr, hdr))) |
145 | return 0; | |
146 | return 1; | |
147 | } | |
148 | ||
149 | static void ext4_xattr_block_csum_set(struct inode *inode, | |
150 | sector_t block_nr, | |
151 | struct ext4_xattr_header *hdr) | |
152 | { | |
9aa5d32b | 153 | if (!ext4_has_metadata_csum(inode->i_sb)) |
cc8e94fd DW |
154 | return; |
155 | ||
156 | hdr->h_checksum = ext4_xattr_block_csum(inode, block_nr, hdr); | |
157 | } | |
158 | ||
159 | static inline int ext4_handle_dirty_xattr_block(handle_t *handle, | |
160 | struct inode *inode, | |
161 | struct buffer_head *bh) | |
162 | { | |
163 | ext4_xattr_block_csum_set(inode, bh->b_blocknr, BHDR(bh)); | |
164 | return ext4_handle_dirty_metadata(handle, inode, bh); | |
165 | } | |
166 | ||
11e27528 | 167 | static inline const struct xattr_handler * |
617ba13b | 168 | ext4_xattr_handler(int name_index) |
ac27a0ec | 169 | { |
11e27528 | 170 | const struct xattr_handler *handler = NULL; |
ac27a0ec | 171 | |
617ba13b MC |
172 | if (name_index > 0 && name_index < ARRAY_SIZE(ext4_xattr_handler_map)) |
173 | handler = ext4_xattr_handler_map[name_index]; | |
ac27a0ec DK |
174 | return handler; |
175 | } | |
176 | ||
177 | /* | |
178 | * Inode operation listxattr() | |
179 | * | |
2b0143b5 | 180 | * d_inode(dentry)->i_mutex: don't care |
ac27a0ec DK |
181 | */ |
182 | ssize_t | |
617ba13b | 183 | ext4_listxattr(struct dentry *dentry, char *buffer, size_t size) |
ac27a0ec | 184 | { |
431547b3 | 185 | return ext4_xattr_list(dentry, buffer, size); |
ac27a0ec DK |
186 | } |
187 | ||
188 | static int | |
a0626e75 DW |
189 | ext4_xattr_check_names(struct ext4_xattr_entry *entry, void *end, |
190 | void *value_start) | |
ac27a0ec | 191 | { |
a0626e75 DW |
192 | struct ext4_xattr_entry *e = entry; |
193 | ||
194 | while (!IS_LAST_ENTRY(e)) { | |
195 | struct ext4_xattr_entry *next = EXT4_XATTR_NEXT(e); | |
ac27a0ec | 196 | if ((void *)next >= end) |
6a797d27 | 197 | return -EFSCORRUPTED; |
a0626e75 | 198 | e = next; |
ac27a0ec | 199 | } |
a0626e75 DW |
200 | |
201 | while (!IS_LAST_ENTRY(entry)) { | |
2de58f11 JK |
202 | if (entry->e_value_block != 0) |
203 | return -EFSCORRUPTED; | |
a0626e75 DW |
204 | if (entry->e_value_size != 0 && |
205 | (value_start + le16_to_cpu(entry->e_value_offs) < | |
206 | (void *)e + sizeof(__u32) || | |
207 | value_start + le16_to_cpu(entry->e_value_offs) + | |
208 | le32_to_cpu(entry->e_value_size) > end)) | |
6a797d27 | 209 | return -EFSCORRUPTED; |
a0626e75 DW |
210 | entry = EXT4_XATTR_NEXT(entry); |
211 | } | |
212 | ||
ac27a0ec DK |
213 | return 0; |
214 | } | |
215 | ||
216 | static inline int | |
cc8e94fd | 217 | ext4_xattr_check_block(struct inode *inode, struct buffer_head *bh) |
ac27a0ec | 218 | { |
cc8e94fd DW |
219 | int error; |
220 | ||
221 | if (buffer_verified(bh)) | |
222 | return 0; | |
223 | ||
617ba13b | 224 | if (BHDR(bh)->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC) || |
ac27a0ec | 225 | BHDR(bh)->h_blocks != cpu_to_le32(1)) |
6a797d27 | 226 | return -EFSCORRUPTED; |
cc8e94fd | 227 | if (!ext4_xattr_block_csum_verify(inode, bh->b_blocknr, BHDR(bh))) |
6a797d27 | 228 | return -EFSBADCRC; |
a0626e75 DW |
229 | error = ext4_xattr_check_names(BFIRST(bh), bh->b_data + bh->b_size, |
230 | bh->b_data); | |
cc8e94fd DW |
231 | if (!error) |
232 | set_buffer_verified(bh); | |
233 | return error; | |
ac27a0ec DK |
234 | } |
235 | ||
9e92f48c TT |
236 | static int |
237 | __xattr_check_inode(struct inode *inode, struct ext4_xattr_ibody_header *header, | |
238 | void *end, const char *function, unsigned int line) | |
239 | { | |
240 | struct ext4_xattr_entry *entry = IFIRST(header); | |
241 | int error = -EFSCORRUPTED; | |
242 | ||
243 | if (((void *) header >= end) || | |
244 | (header->h_magic != le32_to_cpu(EXT4_XATTR_MAGIC))) | |
245 | goto errout; | |
246 | error = ext4_xattr_check_names(entry, end, entry); | |
247 | errout: | |
248 | if (error) | |
249 | __ext4_error_inode(inode, function, line, 0, | |
250 | "corrupted in-inode xattr"); | |
251 | return error; | |
252 | } | |
253 | ||
254 | #define xattr_check_inode(inode, header, end) \ | |
255 | __xattr_check_inode((inode), (header), (end), __func__, __LINE__) | |
256 | ||
ac27a0ec | 257 | static inline int |
617ba13b | 258 | ext4_xattr_check_entry(struct ext4_xattr_entry *entry, size_t size) |
ac27a0ec DK |
259 | { |
260 | size_t value_size = le32_to_cpu(entry->e_value_size); | |
261 | ||
262 | if (entry->e_value_block != 0 || value_size > size || | |
263 | le16_to_cpu(entry->e_value_offs) + value_size > size) | |
6a797d27 | 264 | return -EFSCORRUPTED; |
ac27a0ec DK |
265 | return 0; |
266 | } | |
267 | ||
268 | static int | |
617ba13b | 269 | ext4_xattr_find_entry(struct ext4_xattr_entry **pentry, int name_index, |
ac27a0ec DK |
270 | const char *name, size_t size, int sorted) |
271 | { | |
617ba13b | 272 | struct ext4_xattr_entry *entry; |
ac27a0ec DK |
273 | size_t name_len; |
274 | int cmp = 1; | |
275 | ||
276 | if (name == NULL) | |
277 | return -EINVAL; | |
278 | name_len = strlen(name); | |
279 | entry = *pentry; | |
617ba13b | 280 | for (; !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) { |
ac27a0ec DK |
281 | cmp = name_index - entry->e_name_index; |
282 | if (!cmp) | |
283 | cmp = name_len - entry->e_name_len; | |
284 | if (!cmp) | |
285 | cmp = memcmp(name, entry->e_name, name_len); | |
286 | if (cmp <= 0 && (sorted || cmp == 0)) | |
287 | break; | |
288 | } | |
289 | *pentry = entry; | |
617ba13b | 290 | if (!cmp && ext4_xattr_check_entry(entry, size)) |
6a797d27 | 291 | return -EFSCORRUPTED; |
ac27a0ec DK |
292 | return cmp ? -ENODATA : 0; |
293 | } | |
294 | ||
295 | static int | |
617ba13b | 296 | ext4_xattr_block_get(struct inode *inode, int name_index, const char *name, |
ac27a0ec DK |
297 | void *buffer, size_t buffer_size) |
298 | { | |
299 | struct buffer_head *bh = NULL; | |
617ba13b | 300 | struct ext4_xattr_entry *entry; |
ac27a0ec DK |
301 | size_t size; |
302 | int error; | |
7a2508e1 | 303 | struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode); |
ac27a0ec DK |
304 | |
305 | ea_idebug(inode, "name=%d.%s, buffer=%p, buffer_size=%ld", | |
306 | name_index, name, buffer, (long)buffer_size); | |
307 | ||
308 | error = -ENODATA; | |
617ba13b | 309 | if (!EXT4_I(inode)->i_file_acl) |
ac27a0ec | 310 | goto cleanup; |
ace36ad4 JP |
311 | ea_idebug(inode, "reading block %llu", |
312 | (unsigned long long)EXT4_I(inode)->i_file_acl); | |
617ba13b | 313 | bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl); |
ac27a0ec DK |
314 | if (!bh) |
315 | goto cleanup; | |
316 | ea_bdebug(bh, "b_count=%d, refcount=%d", | |
317 | atomic_read(&(bh->b_count)), le32_to_cpu(BHDR(bh)->h_refcount)); | |
cc8e94fd | 318 | if (ext4_xattr_check_block(inode, bh)) { |
12062ddd | 319 | bad_block: |
24676da4 TT |
320 | EXT4_ERROR_INODE(inode, "bad block %llu", |
321 | EXT4_I(inode)->i_file_acl); | |
6a797d27 | 322 | error = -EFSCORRUPTED; |
ac27a0ec DK |
323 | goto cleanup; |
324 | } | |
9c191f70 | 325 | ext4_xattr_cache_insert(ext4_mb_cache, bh); |
ac27a0ec | 326 | entry = BFIRST(bh); |
617ba13b | 327 | error = ext4_xattr_find_entry(&entry, name_index, name, bh->b_size, 1); |
6a797d27 | 328 | if (error == -EFSCORRUPTED) |
ac27a0ec DK |
329 | goto bad_block; |
330 | if (error) | |
331 | goto cleanup; | |
332 | size = le32_to_cpu(entry->e_value_size); | |
333 | if (buffer) { | |
334 | error = -ERANGE; | |
335 | if (size > buffer_size) | |
336 | goto cleanup; | |
337 | memcpy(buffer, bh->b_data + le16_to_cpu(entry->e_value_offs), | |
338 | size); | |
339 | } | |
340 | error = size; | |
341 | ||
342 | cleanup: | |
343 | brelse(bh); | |
344 | return error; | |
345 | } | |
346 | ||
879b3825 | 347 | int |
617ba13b | 348 | ext4_xattr_ibody_get(struct inode *inode, int name_index, const char *name, |
ac27a0ec DK |
349 | void *buffer, size_t buffer_size) |
350 | { | |
617ba13b MC |
351 | struct ext4_xattr_ibody_header *header; |
352 | struct ext4_xattr_entry *entry; | |
353 | struct ext4_inode *raw_inode; | |
354 | struct ext4_iloc iloc; | |
ac27a0ec DK |
355 | size_t size; |
356 | void *end; | |
357 | int error; | |
358 | ||
19f5fb7a | 359 | if (!ext4_test_inode_state(inode, EXT4_STATE_XATTR)) |
ac27a0ec | 360 | return -ENODATA; |
617ba13b | 361 | error = ext4_get_inode_loc(inode, &iloc); |
ac27a0ec DK |
362 | if (error) |
363 | return error; | |
617ba13b | 364 | raw_inode = ext4_raw_inode(&iloc); |
ac27a0ec DK |
365 | header = IHDR(inode, raw_inode); |
366 | entry = IFIRST(header); | |
617ba13b | 367 | end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; |
9e92f48c | 368 | error = xattr_check_inode(inode, header, end); |
ac27a0ec DK |
369 | if (error) |
370 | goto cleanup; | |
617ba13b | 371 | error = ext4_xattr_find_entry(&entry, name_index, name, |
ac27a0ec DK |
372 | end - (void *)entry, 0); |
373 | if (error) | |
374 | goto cleanup; | |
375 | size = le32_to_cpu(entry->e_value_size); | |
376 | if (buffer) { | |
377 | error = -ERANGE; | |
378 | if (size > buffer_size) | |
379 | goto cleanup; | |
380 | memcpy(buffer, (void *)IFIRST(header) + | |
381 | le16_to_cpu(entry->e_value_offs), size); | |
382 | } | |
383 | error = size; | |
384 | ||
385 | cleanup: | |
386 | brelse(iloc.bh); | |
387 | return error; | |
388 | } | |
389 | ||
390 | /* | |
617ba13b | 391 | * ext4_xattr_get() |
ac27a0ec DK |
392 | * |
393 | * Copy an extended attribute into the buffer | |
394 | * provided, or compute the buffer size required. | |
395 | * Buffer is NULL to compute the size of the buffer required. | |
396 | * | |
397 | * Returns a negative error number on failure, or the number of bytes | |
398 | * used / required on success. | |
399 | */ | |
400 | int | |
617ba13b | 401 | ext4_xattr_get(struct inode *inode, int name_index, const char *name, |
ac27a0ec DK |
402 | void *buffer, size_t buffer_size) |
403 | { | |
404 | int error; | |
405 | ||
230b8c1a ZZ |
406 | if (strlen(name) > 255) |
407 | return -ERANGE; | |
408 | ||
617ba13b MC |
409 | down_read(&EXT4_I(inode)->xattr_sem); |
410 | error = ext4_xattr_ibody_get(inode, name_index, name, buffer, | |
ac27a0ec DK |
411 | buffer_size); |
412 | if (error == -ENODATA) | |
617ba13b | 413 | error = ext4_xattr_block_get(inode, name_index, name, buffer, |
ac27a0ec | 414 | buffer_size); |
617ba13b | 415 | up_read(&EXT4_I(inode)->xattr_sem); |
ac27a0ec DK |
416 | return error; |
417 | } | |
418 | ||
419 | static int | |
431547b3 | 420 | ext4_xattr_list_entries(struct dentry *dentry, struct ext4_xattr_entry *entry, |
ac27a0ec DK |
421 | char *buffer, size_t buffer_size) |
422 | { | |
423 | size_t rest = buffer_size; | |
424 | ||
617ba13b | 425 | for (; !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) { |
11e27528 | 426 | const struct xattr_handler *handler = |
617ba13b | 427 | ext4_xattr_handler(entry->e_name_index); |
ac27a0ec | 428 | |
764a5c6b AG |
429 | if (handler && (!handler->list || handler->list(dentry))) { |
430 | const char *prefix = handler->prefix ?: handler->name; | |
431 | size_t prefix_len = strlen(prefix); | |
432 | size_t size = prefix_len + entry->e_name_len + 1; | |
433 | ||
ac27a0ec DK |
434 | if (buffer) { |
435 | if (size > rest) | |
436 | return -ERANGE; | |
764a5c6b AG |
437 | memcpy(buffer, prefix, prefix_len); |
438 | buffer += prefix_len; | |
439 | memcpy(buffer, entry->e_name, entry->e_name_len); | |
440 | buffer += entry->e_name_len; | |
441 | *buffer++ = 0; | |
ac27a0ec DK |
442 | } |
443 | rest -= size; | |
444 | } | |
445 | } | |
764a5c6b | 446 | return buffer_size - rest; /* total size */ |
ac27a0ec DK |
447 | } |
448 | ||
449 | static int | |
431547b3 | 450 | ext4_xattr_block_list(struct dentry *dentry, char *buffer, size_t buffer_size) |
ac27a0ec | 451 | { |
2b0143b5 | 452 | struct inode *inode = d_inode(dentry); |
ac27a0ec DK |
453 | struct buffer_head *bh = NULL; |
454 | int error; | |
7a2508e1 | 455 | struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode); |
ac27a0ec DK |
456 | |
457 | ea_idebug(inode, "buffer=%p, buffer_size=%ld", | |
458 | buffer, (long)buffer_size); | |
459 | ||
460 | error = 0; | |
617ba13b | 461 | if (!EXT4_I(inode)->i_file_acl) |
ac27a0ec | 462 | goto cleanup; |
ace36ad4 JP |
463 | ea_idebug(inode, "reading block %llu", |
464 | (unsigned long long)EXT4_I(inode)->i_file_acl); | |
617ba13b | 465 | bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl); |
ac27a0ec DK |
466 | error = -EIO; |
467 | if (!bh) | |
468 | goto cleanup; | |
469 | ea_bdebug(bh, "b_count=%d, refcount=%d", | |
470 | atomic_read(&(bh->b_count)), le32_to_cpu(BHDR(bh)->h_refcount)); | |
cc8e94fd | 471 | if (ext4_xattr_check_block(inode, bh)) { |
24676da4 TT |
472 | EXT4_ERROR_INODE(inode, "bad block %llu", |
473 | EXT4_I(inode)->i_file_acl); | |
6a797d27 | 474 | error = -EFSCORRUPTED; |
ac27a0ec DK |
475 | goto cleanup; |
476 | } | |
9c191f70 | 477 | ext4_xattr_cache_insert(ext4_mb_cache, bh); |
431547b3 | 478 | error = ext4_xattr_list_entries(dentry, BFIRST(bh), buffer, buffer_size); |
ac27a0ec DK |
479 | |
480 | cleanup: | |
481 | brelse(bh); | |
482 | ||
483 | return error; | |
484 | } | |
485 | ||
486 | static int | |
431547b3 | 487 | ext4_xattr_ibody_list(struct dentry *dentry, char *buffer, size_t buffer_size) |
ac27a0ec | 488 | { |
2b0143b5 | 489 | struct inode *inode = d_inode(dentry); |
617ba13b MC |
490 | struct ext4_xattr_ibody_header *header; |
491 | struct ext4_inode *raw_inode; | |
492 | struct ext4_iloc iloc; | |
ac27a0ec DK |
493 | void *end; |
494 | int error; | |
495 | ||
19f5fb7a | 496 | if (!ext4_test_inode_state(inode, EXT4_STATE_XATTR)) |
ac27a0ec | 497 | return 0; |
617ba13b | 498 | error = ext4_get_inode_loc(inode, &iloc); |
ac27a0ec DK |
499 | if (error) |
500 | return error; | |
617ba13b | 501 | raw_inode = ext4_raw_inode(&iloc); |
ac27a0ec | 502 | header = IHDR(inode, raw_inode); |
617ba13b | 503 | end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; |
9e92f48c | 504 | error = xattr_check_inode(inode, header, end); |
ac27a0ec DK |
505 | if (error) |
506 | goto cleanup; | |
431547b3 | 507 | error = ext4_xattr_list_entries(dentry, IFIRST(header), |
ac27a0ec DK |
508 | buffer, buffer_size); |
509 | ||
510 | cleanup: | |
511 | brelse(iloc.bh); | |
512 | return error; | |
513 | } | |
514 | ||
515 | /* | |
617ba13b | 516 | * ext4_xattr_list() |
ac27a0ec DK |
517 | * |
518 | * Copy a list of attribute names into the buffer | |
519 | * provided, or compute the buffer size required. | |
520 | * Buffer is NULL to compute the size of the buffer required. | |
521 | * | |
522 | * Returns a negative error number on failure, or the number of bytes | |
523 | * used / required on success. | |
524 | */ | |
d3a95d47 | 525 | static int |
431547b3 | 526 | ext4_xattr_list(struct dentry *dentry, char *buffer, size_t buffer_size) |
ac27a0ec | 527 | { |
eaeef867 | 528 | int ret, ret2; |
ac27a0ec | 529 | |
2b0143b5 | 530 | down_read(&EXT4_I(d_inode(dentry))->xattr_sem); |
eaeef867 TT |
531 | ret = ret2 = ext4_xattr_ibody_list(dentry, buffer, buffer_size); |
532 | if (ret < 0) | |
533 | goto errout; | |
534 | if (buffer) { | |
535 | buffer += ret; | |
536 | buffer_size -= ret; | |
ac27a0ec | 537 | } |
eaeef867 TT |
538 | ret = ext4_xattr_block_list(dentry, buffer, buffer_size); |
539 | if (ret < 0) | |
540 | goto errout; | |
541 | ret += ret2; | |
542 | errout: | |
2b0143b5 | 543 | up_read(&EXT4_I(d_inode(dentry))->xattr_sem); |
eaeef867 | 544 | return ret; |
ac27a0ec DK |
545 | } |
546 | ||
547 | /* | |
617ba13b | 548 | * If the EXT4_FEATURE_COMPAT_EXT_ATTR feature of this file system is |
ac27a0ec DK |
549 | * not set, set it. |
550 | */ | |
617ba13b | 551 | static void ext4_xattr_update_super_block(handle_t *handle, |
ac27a0ec DK |
552 | struct super_block *sb) |
553 | { | |
e2b911c5 | 554 | if (ext4_has_feature_xattr(sb)) |
ac27a0ec DK |
555 | return; |
556 | ||
5d601255 | 557 | BUFFER_TRACE(EXT4_SB(sb)->s_sbh, "get_write_access"); |
617ba13b | 558 | if (ext4_journal_get_write_access(handle, EXT4_SB(sb)->s_sbh) == 0) { |
e2b911c5 | 559 | ext4_set_feature_xattr(sb); |
a0375156 | 560 | ext4_handle_dirty_super(handle, sb); |
ac27a0ec | 561 | } |
ac27a0ec DK |
562 | } |
563 | ||
564 | /* | |
ec4cb1aa JK |
565 | * Release the xattr block BH: If the reference count is > 1, decrement it; |
566 | * otherwise free the block. | |
ac27a0ec DK |
567 | */ |
568 | static void | |
617ba13b | 569 | ext4_xattr_release_block(handle_t *handle, struct inode *inode, |
ac27a0ec DK |
570 | struct buffer_head *bh) |
571 | { | |
6048c64b AG |
572 | struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode); |
573 | u32 hash, ref; | |
8a2bfdcb | 574 | int error = 0; |
ac27a0ec | 575 | |
5d601255 | 576 | BUFFER_TRACE(bh, "get_write_access"); |
8a2bfdcb MC |
577 | error = ext4_journal_get_write_access(handle, bh); |
578 | if (error) | |
579 | goto out; | |
580 | ||
581 | lock_buffer(bh); | |
6048c64b AG |
582 | hash = le32_to_cpu(BHDR(bh)->h_hash); |
583 | ref = le32_to_cpu(BHDR(bh)->h_refcount); | |
584 | if (ref == 1) { | |
ac27a0ec | 585 | ea_bdebug(bh, "refcount now=0; freeing"); |
82939d79 JK |
586 | /* |
587 | * This must happen under buffer lock for | |
588 | * ext4_xattr_block_set() to reliably detect freed block | |
589 | */ | |
6048c64b | 590 | mb_cache_entry_delete_block(ext4_mb_cache, hash, bh->b_blocknr); |
ac27a0ec | 591 | get_bh(bh); |
ec4cb1aa | 592 | unlock_buffer(bh); |
e6362609 TT |
593 | ext4_free_blocks(handle, inode, bh, 0, 1, |
594 | EXT4_FREE_BLOCKS_METADATA | | |
595 | EXT4_FREE_BLOCKS_FORGET); | |
ac27a0ec | 596 | } else { |
6048c64b AG |
597 | ref--; |
598 | BHDR(bh)->h_refcount = cpu_to_le32(ref); | |
599 | if (ref == EXT4_XATTR_REFCOUNT_MAX - 1) { | |
600 | struct mb_cache_entry *ce; | |
601 | ||
602 | ce = mb_cache_entry_get(ext4_mb_cache, hash, | |
603 | bh->b_blocknr); | |
604 | if (ce) { | |
605 | ce->e_reusable = 1; | |
606 | mb_cache_entry_put(ext4_mb_cache, ce); | |
607 | } | |
608 | } | |
609 | ||
ec4cb1aa JK |
610 | /* |
611 | * Beware of this ugliness: Releasing of xattr block references | |
612 | * from different inodes can race and so we have to protect | |
613 | * from a race where someone else frees the block (and releases | |
614 | * its journal_head) before we are done dirtying the buffer. In | |
615 | * nojournal mode this race is harmless and we actually cannot | |
616 | * call ext4_handle_dirty_xattr_block() with locked buffer as | |
617 | * that function can call sync_dirty_buffer() so for that case | |
618 | * we handle the dirtying after unlocking the buffer. | |
619 | */ | |
620 | if (ext4_handle_valid(handle)) | |
621 | error = ext4_handle_dirty_xattr_block(handle, inode, | |
622 | bh); | |
c1bb05a6 | 623 | unlock_buffer(bh); |
ec4cb1aa JK |
624 | if (!ext4_handle_valid(handle)) |
625 | error = ext4_handle_dirty_xattr_block(handle, inode, | |
626 | bh); | |
8a2bfdcb | 627 | if (IS_SYNC(inode)) |
0390131b | 628 | ext4_handle_sync(handle); |
1231b3a1 | 629 | dquot_free_block(inode, EXT4_C2B(EXT4_SB(inode->i_sb), 1)); |
8a2bfdcb MC |
630 | ea_bdebug(bh, "refcount now=%d; releasing", |
631 | le32_to_cpu(BHDR(bh)->h_refcount)); | |
ac27a0ec | 632 | } |
8a2bfdcb MC |
633 | out: |
634 | ext4_std_error(inode->i_sb, error); | |
635 | return; | |
ac27a0ec DK |
636 | } |
637 | ||
6dd4ee7c KS |
638 | /* |
639 | * Find the available free space for EAs. This also returns the total number of | |
640 | * bytes used by EA entries. | |
641 | */ | |
642 | static size_t ext4_xattr_free_space(struct ext4_xattr_entry *last, | |
643 | size_t *min_offs, void *base, int *total) | |
644 | { | |
645 | for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) { | |
1cba4237 | 646 | if (last->e_value_size) { |
6dd4ee7c KS |
647 | size_t offs = le16_to_cpu(last->e_value_offs); |
648 | if (offs < *min_offs) | |
649 | *min_offs = offs; | |
650 | } | |
7b1b2c1b TT |
651 | if (total) |
652 | *total += EXT4_XATTR_LEN(last->e_name_len); | |
6dd4ee7c KS |
653 | } |
654 | return (*min_offs - ((void *)last - base) - sizeof(__u32)); | |
655 | } | |
656 | ||
ac27a0ec | 657 | static int |
617ba13b | 658 | ext4_xattr_set_entry(struct ext4_xattr_info *i, struct ext4_xattr_search *s) |
ac27a0ec | 659 | { |
617ba13b | 660 | struct ext4_xattr_entry *last; |
ac27a0ec DK |
661 | size_t free, min_offs = s->end - s->base, name_len = strlen(i->name); |
662 | ||
663 | /* Compute min_offs and last. */ | |
664 | last = s->first; | |
617ba13b | 665 | for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) { |
1cba4237 | 666 | if (last->e_value_size) { |
ac27a0ec DK |
667 | size_t offs = le16_to_cpu(last->e_value_offs); |
668 | if (offs < min_offs) | |
669 | min_offs = offs; | |
670 | } | |
671 | } | |
672 | free = min_offs - ((void *)last - s->base) - sizeof(__u32); | |
673 | if (!s->not_found) { | |
1cba4237 | 674 | if (s->here->e_value_size) { |
ac27a0ec | 675 | size_t size = le32_to_cpu(s->here->e_value_size); |
617ba13b | 676 | free += EXT4_XATTR_SIZE(size); |
ac27a0ec | 677 | } |
617ba13b | 678 | free += EXT4_XATTR_LEN(name_len); |
ac27a0ec DK |
679 | } |
680 | if (i->value) { | |
5f80f62a | 681 | if (free < EXT4_XATTR_LEN(name_len) + |
617ba13b | 682 | EXT4_XATTR_SIZE(i->value_len)) |
ac27a0ec DK |
683 | return -ENOSPC; |
684 | } | |
685 | ||
686 | if (i->value && s->not_found) { | |
687 | /* Insert the new name. */ | |
617ba13b | 688 | size_t size = EXT4_XATTR_LEN(name_len); |
ac27a0ec DK |
689 | size_t rest = (void *)last - (void *)s->here + sizeof(__u32); |
690 | memmove((void *)s->here + size, s->here, rest); | |
691 | memset(s->here, 0, size); | |
692 | s->here->e_name_index = i->name_index; | |
693 | s->here->e_name_len = name_len; | |
694 | memcpy(s->here->e_name, i->name, name_len); | |
695 | } else { | |
1cba4237 | 696 | if (s->here->e_value_size) { |
ac27a0ec DK |
697 | void *first_val = s->base + min_offs; |
698 | size_t offs = le16_to_cpu(s->here->e_value_offs); | |
699 | void *val = s->base + offs; | |
617ba13b | 700 | size_t size = EXT4_XATTR_SIZE( |
ac27a0ec DK |
701 | le32_to_cpu(s->here->e_value_size)); |
702 | ||
617ba13b | 703 | if (i->value && size == EXT4_XATTR_SIZE(i->value_len)) { |
ac27a0ec DK |
704 | /* The old and the new value have the same |
705 | size. Just replace. */ | |
706 | s->here->e_value_size = | |
707 | cpu_to_le32(i->value_len); | |
bd9926e8 TT |
708 | if (i->value == EXT4_ZERO_XATTR_VALUE) { |
709 | memset(val, 0, size); | |
710 | } else { | |
711 | /* Clear pad bytes first. */ | |
712 | memset(val + size - EXT4_XATTR_PAD, 0, | |
713 | EXT4_XATTR_PAD); | |
714 | memcpy(val, i->value, i->value_len); | |
715 | } | |
ac27a0ec DK |
716 | return 0; |
717 | } | |
718 | ||
719 | /* Remove the old value. */ | |
720 | memmove(first_val + size, first_val, val - first_val); | |
721 | memset(first_val, 0, size); | |
722 | s->here->e_value_size = 0; | |
723 | s->here->e_value_offs = 0; | |
724 | min_offs += size; | |
725 | ||
726 | /* Adjust all value offsets. */ | |
727 | last = s->first; | |
728 | while (!IS_LAST_ENTRY(last)) { | |
729 | size_t o = le16_to_cpu(last->e_value_offs); | |
1cba4237 | 730 | if (last->e_value_size && o < offs) |
ac27a0ec DK |
731 | last->e_value_offs = |
732 | cpu_to_le16(o + size); | |
617ba13b | 733 | last = EXT4_XATTR_NEXT(last); |
ac27a0ec DK |
734 | } |
735 | } | |
736 | if (!i->value) { | |
737 | /* Remove the old name. */ | |
617ba13b | 738 | size_t size = EXT4_XATTR_LEN(name_len); |
ac27a0ec DK |
739 | last = ENTRY((void *)last - size); |
740 | memmove(s->here, (void *)s->here + size, | |
741 | (void *)last - (void *)s->here + sizeof(__u32)); | |
742 | memset(last, 0, size); | |
743 | } | |
744 | } | |
745 | ||
746 | if (i->value) { | |
747 | /* Insert the new value. */ | |
748 | s->here->e_value_size = cpu_to_le32(i->value_len); | |
749 | if (i->value_len) { | |
617ba13b | 750 | size_t size = EXT4_XATTR_SIZE(i->value_len); |
ac27a0ec DK |
751 | void *val = s->base + min_offs - size; |
752 | s->here->e_value_offs = cpu_to_le16(min_offs - size); | |
bd9926e8 TT |
753 | if (i->value == EXT4_ZERO_XATTR_VALUE) { |
754 | memset(val, 0, size); | |
755 | } else { | |
756 | /* Clear the pad bytes first. */ | |
757 | memset(val + size - EXT4_XATTR_PAD, 0, | |
758 | EXT4_XATTR_PAD); | |
759 | memcpy(val, i->value, i->value_len); | |
760 | } | |
ac27a0ec DK |
761 | } |
762 | } | |
763 | return 0; | |
764 | } | |
765 | ||
617ba13b MC |
766 | struct ext4_xattr_block_find { |
767 | struct ext4_xattr_search s; | |
ac27a0ec DK |
768 | struct buffer_head *bh; |
769 | }; | |
770 | ||
771 | static int | |
617ba13b MC |
772 | ext4_xattr_block_find(struct inode *inode, struct ext4_xattr_info *i, |
773 | struct ext4_xattr_block_find *bs) | |
ac27a0ec DK |
774 | { |
775 | struct super_block *sb = inode->i_sb; | |
776 | int error; | |
777 | ||
778 | ea_idebug(inode, "name=%d.%s, value=%p, value_len=%ld", | |
779 | i->name_index, i->name, i->value, (long)i->value_len); | |
780 | ||
617ba13b | 781 | if (EXT4_I(inode)->i_file_acl) { |
ac27a0ec | 782 | /* The inode already has an extended attribute block. */ |
617ba13b | 783 | bs->bh = sb_bread(sb, EXT4_I(inode)->i_file_acl); |
ac27a0ec DK |
784 | error = -EIO; |
785 | if (!bs->bh) | |
786 | goto cleanup; | |
787 | ea_bdebug(bs->bh, "b_count=%d, refcount=%d", | |
788 | atomic_read(&(bs->bh->b_count)), | |
789 | le32_to_cpu(BHDR(bs->bh)->h_refcount)); | |
cc8e94fd | 790 | if (ext4_xattr_check_block(inode, bs->bh)) { |
24676da4 TT |
791 | EXT4_ERROR_INODE(inode, "bad block %llu", |
792 | EXT4_I(inode)->i_file_acl); | |
6a797d27 | 793 | error = -EFSCORRUPTED; |
ac27a0ec DK |
794 | goto cleanup; |
795 | } | |
796 | /* Find the named attribute. */ | |
797 | bs->s.base = BHDR(bs->bh); | |
798 | bs->s.first = BFIRST(bs->bh); | |
799 | bs->s.end = bs->bh->b_data + bs->bh->b_size; | |
800 | bs->s.here = bs->s.first; | |
617ba13b | 801 | error = ext4_xattr_find_entry(&bs->s.here, i->name_index, |
ac27a0ec DK |
802 | i->name, bs->bh->b_size, 1); |
803 | if (error && error != -ENODATA) | |
804 | goto cleanup; | |
805 | bs->s.not_found = error; | |
806 | } | |
807 | error = 0; | |
808 | ||
809 | cleanup: | |
810 | return error; | |
811 | } | |
812 | ||
813 | static int | |
617ba13b MC |
814 | ext4_xattr_block_set(handle_t *handle, struct inode *inode, |
815 | struct ext4_xattr_info *i, | |
816 | struct ext4_xattr_block_find *bs) | |
ac27a0ec DK |
817 | { |
818 | struct super_block *sb = inode->i_sb; | |
819 | struct buffer_head *new_bh = NULL; | |
617ba13b | 820 | struct ext4_xattr_search *s = &bs->s; |
7a2508e1 | 821 | struct mb_cache_entry *ce = NULL; |
8a2bfdcb | 822 | int error = 0; |
7a2508e1 | 823 | struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode); |
ac27a0ec | 824 | |
617ba13b | 825 | #define header(x) ((struct ext4_xattr_header *)(x)) |
ac27a0ec DK |
826 | |
827 | if (i->value && i->value_len > sb->s_blocksize) | |
828 | return -ENOSPC; | |
829 | if (s->base) { | |
5d601255 | 830 | BUFFER_TRACE(bs->bh, "get_write_access"); |
8a2bfdcb MC |
831 | error = ext4_journal_get_write_access(handle, bs->bh); |
832 | if (error) | |
833 | goto cleanup; | |
834 | lock_buffer(bs->bh); | |
835 | ||
ac27a0ec | 836 | if (header(s->base)->h_refcount == cpu_to_le32(1)) { |
82939d79 JK |
837 | __u32 hash = le32_to_cpu(BHDR(bs->bh)->h_hash); |
838 | ||
839 | /* | |
840 | * This must happen under buffer lock for | |
841 | * ext4_xattr_block_set() to reliably detect modified | |
842 | * block | |
843 | */ | |
7a2508e1 JK |
844 | mb_cache_entry_delete_block(ext4_mb_cache, hash, |
845 | bs->bh->b_blocknr); | |
ac27a0ec | 846 | ea_bdebug(bs->bh, "modifying in-place"); |
617ba13b | 847 | error = ext4_xattr_set_entry(i, s); |
ac27a0ec DK |
848 | if (!error) { |
849 | if (!IS_LAST_ENTRY(s->first)) | |
617ba13b | 850 | ext4_xattr_rehash(header(s->base), |
ac27a0ec | 851 | s->here); |
9c191f70 M |
852 | ext4_xattr_cache_insert(ext4_mb_cache, |
853 | bs->bh); | |
ac27a0ec DK |
854 | } |
855 | unlock_buffer(bs->bh); | |
6a797d27 | 856 | if (error == -EFSCORRUPTED) |
ac27a0ec DK |
857 | goto bad_block; |
858 | if (!error) | |
cc8e94fd DW |
859 | error = ext4_handle_dirty_xattr_block(handle, |
860 | inode, | |
861 | bs->bh); | |
ac27a0ec DK |
862 | if (error) |
863 | goto cleanup; | |
864 | goto inserted; | |
865 | } else { | |
866 | int offset = (char *)s->here - bs->bh->b_data; | |
867 | ||
8a2bfdcb | 868 | unlock_buffer(bs->bh); |
ac27a0ec | 869 | ea_bdebug(bs->bh, "cloning"); |
216553c4 | 870 | s->base = kmalloc(bs->bh->b_size, GFP_NOFS); |
ac27a0ec DK |
871 | error = -ENOMEM; |
872 | if (s->base == NULL) | |
873 | goto cleanup; | |
874 | memcpy(s->base, BHDR(bs->bh), bs->bh->b_size); | |
875 | s->first = ENTRY(header(s->base)+1); | |
876 | header(s->base)->h_refcount = cpu_to_le32(1); | |
877 | s->here = ENTRY(s->base + offset); | |
878 | s->end = s->base + bs->bh->b_size; | |
879 | } | |
880 | } else { | |
881 | /* Allocate a buffer where we construct the new block. */ | |
216553c4 | 882 | s->base = kzalloc(sb->s_blocksize, GFP_NOFS); |
ac27a0ec DK |
883 | /* assert(header == s->base) */ |
884 | error = -ENOMEM; | |
885 | if (s->base == NULL) | |
886 | goto cleanup; | |
617ba13b | 887 | header(s->base)->h_magic = cpu_to_le32(EXT4_XATTR_MAGIC); |
ac27a0ec DK |
888 | header(s->base)->h_blocks = cpu_to_le32(1); |
889 | header(s->base)->h_refcount = cpu_to_le32(1); | |
890 | s->first = ENTRY(header(s->base)+1); | |
891 | s->here = ENTRY(header(s->base)+1); | |
892 | s->end = s->base + sb->s_blocksize; | |
893 | } | |
894 | ||
617ba13b | 895 | error = ext4_xattr_set_entry(i, s); |
6a797d27 | 896 | if (error == -EFSCORRUPTED) |
ac27a0ec DK |
897 | goto bad_block; |
898 | if (error) | |
899 | goto cleanup; | |
900 | if (!IS_LAST_ENTRY(s->first)) | |
617ba13b | 901 | ext4_xattr_rehash(header(s->base), s->here); |
ac27a0ec DK |
902 | |
903 | inserted: | |
904 | if (!IS_LAST_ENTRY(s->first)) { | |
617ba13b | 905 | new_bh = ext4_xattr_cache_find(inode, header(s->base), &ce); |
ac27a0ec DK |
906 | if (new_bh) { |
907 | /* We found an identical block in the cache. */ | |
908 | if (new_bh == bs->bh) | |
909 | ea_bdebug(new_bh, "keeping"); | |
910 | else { | |
6048c64b AG |
911 | u32 ref; |
912 | ||
ac27a0ec DK |
913 | /* The old block is released after updating |
914 | the inode. */ | |
1231b3a1 LC |
915 | error = dquot_alloc_block(inode, |
916 | EXT4_C2B(EXT4_SB(sb), 1)); | |
5dd4056d | 917 | if (error) |
ac27a0ec | 918 | goto cleanup; |
5d601255 | 919 | BUFFER_TRACE(new_bh, "get_write_access"); |
617ba13b | 920 | error = ext4_journal_get_write_access(handle, |
ac27a0ec DK |
921 | new_bh); |
922 | if (error) | |
923 | goto cleanup_dquot; | |
924 | lock_buffer(new_bh); | |
82939d79 JK |
925 | /* |
926 | * We have to be careful about races with | |
6048c64b AG |
927 | * freeing, rehashing or adding references to |
928 | * xattr block. Once we hold buffer lock xattr | |
929 | * block's state is stable so we can check | |
930 | * whether the block got freed / rehashed or | |
931 | * not. Since we unhash mbcache entry under | |
932 | * buffer lock when freeing / rehashing xattr | |
933 | * block, checking whether entry is still | |
934 | * hashed is reliable. Same rules hold for | |
935 | * e_reusable handling. | |
82939d79 | 936 | */ |
6048c64b AG |
937 | if (hlist_bl_unhashed(&ce->e_hash_list) || |
938 | !ce->e_reusable) { | |
82939d79 JK |
939 | /* |
940 | * Undo everything and check mbcache | |
941 | * again. | |
942 | */ | |
943 | unlock_buffer(new_bh); | |
944 | dquot_free_block(inode, | |
945 | EXT4_C2B(EXT4_SB(sb), | |
946 | 1)); | |
947 | brelse(new_bh); | |
7a2508e1 | 948 | mb_cache_entry_put(ext4_mb_cache, ce); |
82939d79 JK |
949 | ce = NULL; |
950 | new_bh = NULL; | |
951 | goto inserted; | |
952 | } | |
6048c64b AG |
953 | ref = le32_to_cpu(BHDR(new_bh)->h_refcount) + 1; |
954 | BHDR(new_bh)->h_refcount = cpu_to_le32(ref); | |
955 | if (ref >= EXT4_XATTR_REFCOUNT_MAX) | |
956 | ce->e_reusable = 0; | |
ac27a0ec | 957 | ea_bdebug(new_bh, "reusing; refcount now=%d", |
6048c64b | 958 | ref); |
ac27a0ec | 959 | unlock_buffer(new_bh); |
cc8e94fd DW |
960 | error = ext4_handle_dirty_xattr_block(handle, |
961 | inode, | |
962 | new_bh); | |
ac27a0ec DK |
963 | if (error) |
964 | goto cleanup_dquot; | |
965 | } | |
7a2508e1 JK |
966 | mb_cache_entry_touch(ext4_mb_cache, ce); |
967 | mb_cache_entry_put(ext4_mb_cache, ce); | |
ac27a0ec DK |
968 | ce = NULL; |
969 | } else if (bs->bh && s->base == bs->bh->b_data) { | |
970 | /* We were modifying this block in-place. */ | |
971 | ea_bdebug(bs->bh, "keeping this block"); | |
972 | new_bh = bs->bh; | |
973 | get_bh(new_bh); | |
974 | } else { | |
975 | /* We need to allocate a new block */ | |
fb0a387d ES |
976 | ext4_fsblk_t goal, block; |
977 | ||
978 | goal = ext4_group_first_block_no(sb, | |
d00a6d7b | 979 | EXT4_I(inode)->i_block_group); |
fb0a387d ES |
980 | |
981 | /* non-extent files can't have physical blocks past 2^32 */ | |
12e9b892 | 982 | if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) |
fb0a387d ES |
983 | goal = goal & EXT4_MAX_BLOCK_FILE_PHYS; |
984 | ||
55f020db AH |
985 | block = ext4_new_meta_blocks(handle, inode, goal, 0, |
986 | NULL, &error); | |
ac27a0ec DK |
987 | if (error) |
988 | goto cleanup; | |
fb0a387d | 989 | |
12e9b892 | 990 | if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) |
fb0a387d ES |
991 | BUG_ON(block > EXT4_MAX_BLOCK_FILE_PHYS); |
992 | ||
ace36ad4 JP |
993 | ea_idebug(inode, "creating block %llu", |
994 | (unsigned long long)block); | |
ac27a0ec DK |
995 | |
996 | new_bh = sb_getblk(sb, block); | |
aebf0243 | 997 | if (unlikely(!new_bh)) { |
860d21e2 | 998 | error = -ENOMEM; |
ac27a0ec | 999 | getblk_failed: |
7dc57615 | 1000 | ext4_free_blocks(handle, inode, NULL, block, 1, |
e6362609 | 1001 | EXT4_FREE_BLOCKS_METADATA); |
ac27a0ec DK |
1002 | goto cleanup; |
1003 | } | |
1004 | lock_buffer(new_bh); | |
617ba13b | 1005 | error = ext4_journal_get_create_access(handle, new_bh); |
ac27a0ec DK |
1006 | if (error) { |
1007 | unlock_buffer(new_bh); | |
860d21e2 | 1008 | error = -EIO; |
ac27a0ec DK |
1009 | goto getblk_failed; |
1010 | } | |
1011 | memcpy(new_bh->b_data, s->base, new_bh->b_size); | |
1012 | set_buffer_uptodate(new_bh); | |
1013 | unlock_buffer(new_bh); | |
9c191f70 | 1014 | ext4_xattr_cache_insert(ext4_mb_cache, new_bh); |
cc8e94fd DW |
1015 | error = ext4_handle_dirty_xattr_block(handle, |
1016 | inode, new_bh); | |
ac27a0ec DK |
1017 | if (error) |
1018 | goto cleanup; | |
1019 | } | |
1020 | } | |
1021 | ||
1022 | /* Update the inode. */ | |
617ba13b | 1023 | EXT4_I(inode)->i_file_acl = new_bh ? new_bh->b_blocknr : 0; |
ac27a0ec DK |
1024 | |
1025 | /* Drop the previous xattr block. */ | |
1026 | if (bs->bh && bs->bh != new_bh) | |
617ba13b | 1027 | ext4_xattr_release_block(handle, inode, bs->bh); |
ac27a0ec DK |
1028 | error = 0; |
1029 | ||
1030 | cleanup: | |
1031 | if (ce) | |
7a2508e1 | 1032 | mb_cache_entry_put(ext4_mb_cache, ce); |
ac27a0ec DK |
1033 | brelse(new_bh); |
1034 | if (!(bs->bh && s->base == bs->bh->b_data)) | |
1035 | kfree(s->base); | |
1036 | ||
1037 | return error; | |
1038 | ||
1039 | cleanup_dquot: | |
1231b3a1 | 1040 | dquot_free_block(inode, EXT4_C2B(EXT4_SB(sb), 1)); |
ac27a0ec DK |
1041 | goto cleanup; |
1042 | ||
1043 | bad_block: | |
24676da4 TT |
1044 | EXT4_ERROR_INODE(inode, "bad block %llu", |
1045 | EXT4_I(inode)->i_file_acl); | |
ac27a0ec DK |
1046 | goto cleanup; |
1047 | ||
1048 | #undef header | |
1049 | } | |
1050 | ||
879b3825 TM |
1051 | int ext4_xattr_ibody_find(struct inode *inode, struct ext4_xattr_info *i, |
1052 | struct ext4_xattr_ibody_find *is) | |
ac27a0ec | 1053 | { |
617ba13b MC |
1054 | struct ext4_xattr_ibody_header *header; |
1055 | struct ext4_inode *raw_inode; | |
ac27a0ec DK |
1056 | int error; |
1057 | ||
617ba13b | 1058 | if (EXT4_I(inode)->i_extra_isize == 0) |
ac27a0ec | 1059 | return 0; |
617ba13b | 1060 | raw_inode = ext4_raw_inode(&is->iloc); |
ac27a0ec DK |
1061 | header = IHDR(inode, raw_inode); |
1062 | is->s.base = is->s.first = IFIRST(header); | |
1063 | is->s.here = is->s.first; | |
617ba13b | 1064 | is->s.end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; |
19f5fb7a | 1065 | if (ext4_test_inode_state(inode, EXT4_STATE_XATTR)) { |
9e92f48c | 1066 | error = xattr_check_inode(inode, header, is->s.end); |
ac27a0ec DK |
1067 | if (error) |
1068 | return error; | |
1069 | /* Find the named attribute. */ | |
617ba13b | 1070 | error = ext4_xattr_find_entry(&is->s.here, i->name_index, |
ac27a0ec DK |
1071 | i->name, is->s.end - |
1072 | (void *)is->s.base, 0); | |
1073 | if (error && error != -ENODATA) | |
1074 | return error; | |
1075 | is->s.not_found = error; | |
1076 | } | |
1077 | return 0; | |
1078 | } | |
1079 | ||
0d812f77 TM |
1080 | int ext4_xattr_ibody_inline_set(handle_t *handle, struct inode *inode, |
1081 | struct ext4_xattr_info *i, | |
1082 | struct ext4_xattr_ibody_find *is) | |
1083 | { | |
1084 | struct ext4_xattr_ibody_header *header; | |
1085 | struct ext4_xattr_search *s = &is->s; | |
1086 | int error; | |
1087 | ||
1088 | if (EXT4_I(inode)->i_extra_isize == 0) | |
1089 | return -ENOSPC; | |
1090 | error = ext4_xattr_set_entry(i, s); | |
1091 | if (error) { | |
1092 | if (error == -ENOSPC && | |
1093 | ext4_has_inline_data(inode)) { | |
1094 | error = ext4_try_to_evict_inline_data(handle, inode, | |
1095 | EXT4_XATTR_LEN(strlen(i->name) + | |
1096 | EXT4_XATTR_SIZE(i->value_len))); | |
1097 | if (error) | |
1098 | return error; | |
1099 | error = ext4_xattr_ibody_find(inode, i, is); | |
1100 | if (error) | |
1101 | return error; | |
1102 | error = ext4_xattr_set_entry(i, s); | |
1103 | } | |
1104 | if (error) | |
1105 | return error; | |
1106 | } | |
1107 | header = IHDR(inode, ext4_raw_inode(&is->iloc)); | |
1108 | if (!IS_LAST_ENTRY(s->first)) { | |
1109 | header->h_magic = cpu_to_le32(EXT4_XATTR_MAGIC); | |
1110 | ext4_set_inode_state(inode, EXT4_STATE_XATTR); | |
1111 | } else { | |
1112 | header->h_magic = cpu_to_le32(0); | |
1113 | ext4_clear_inode_state(inode, EXT4_STATE_XATTR); | |
1114 | } | |
1115 | return 0; | |
1116 | } | |
1117 | ||
1118 | static int ext4_xattr_ibody_set(handle_t *handle, struct inode *inode, | |
1119 | struct ext4_xattr_info *i, | |
1120 | struct ext4_xattr_ibody_find *is) | |
ac27a0ec | 1121 | { |
617ba13b MC |
1122 | struct ext4_xattr_ibody_header *header; |
1123 | struct ext4_xattr_search *s = &is->s; | |
ac27a0ec DK |
1124 | int error; |
1125 | ||
617ba13b | 1126 | if (EXT4_I(inode)->i_extra_isize == 0) |
ac27a0ec | 1127 | return -ENOSPC; |
617ba13b | 1128 | error = ext4_xattr_set_entry(i, s); |
ac27a0ec DK |
1129 | if (error) |
1130 | return error; | |
617ba13b | 1131 | header = IHDR(inode, ext4_raw_inode(&is->iloc)); |
ac27a0ec | 1132 | if (!IS_LAST_ENTRY(s->first)) { |
617ba13b | 1133 | header->h_magic = cpu_to_le32(EXT4_XATTR_MAGIC); |
19f5fb7a | 1134 | ext4_set_inode_state(inode, EXT4_STATE_XATTR); |
ac27a0ec DK |
1135 | } else { |
1136 | header->h_magic = cpu_to_le32(0); | |
19f5fb7a | 1137 | ext4_clear_inode_state(inode, EXT4_STATE_XATTR); |
ac27a0ec DK |
1138 | } |
1139 | return 0; | |
1140 | } | |
1141 | ||
3fd16462 JK |
1142 | static int ext4_xattr_value_same(struct ext4_xattr_search *s, |
1143 | struct ext4_xattr_info *i) | |
1144 | { | |
1145 | void *value; | |
1146 | ||
1147 | if (le32_to_cpu(s->here->e_value_size) != i->value_len) | |
1148 | return 0; | |
1149 | value = ((void *)s->base) + le16_to_cpu(s->here->e_value_offs); | |
1150 | return !memcmp(value, i->value, i->value_len); | |
1151 | } | |
1152 | ||
ac27a0ec | 1153 | /* |
617ba13b | 1154 | * ext4_xattr_set_handle() |
ac27a0ec | 1155 | * |
6e9510b0 | 1156 | * Create, replace or remove an extended attribute for this inode. Value |
ac27a0ec DK |
1157 | * is NULL to remove an existing extended attribute, and non-NULL to |
1158 | * either replace an existing extended attribute, or create a new extended | |
1159 | * attribute. The flags XATTR_REPLACE and XATTR_CREATE | |
1160 | * specify that an extended attribute must exist and must not exist | |
1161 | * previous to the call, respectively. | |
1162 | * | |
1163 | * Returns 0, or a negative error number on failure. | |
1164 | */ | |
1165 | int | |
617ba13b | 1166 | ext4_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index, |
ac27a0ec DK |
1167 | const char *name, const void *value, size_t value_len, |
1168 | int flags) | |
1169 | { | |
617ba13b | 1170 | struct ext4_xattr_info i = { |
ac27a0ec DK |
1171 | .name_index = name_index, |
1172 | .name = name, | |
1173 | .value = value, | |
1174 | .value_len = value_len, | |
1175 | ||
1176 | }; | |
617ba13b | 1177 | struct ext4_xattr_ibody_find is = { |
ac27a0ec DK |
1178 | .s = { .not_found = -ENODATA, }, |
1179 | }; | |
617ba13b | 1180 | struct ext4_xattr_block_find bs = { |
ac27a0ec DK |
1181 | .s = { .not_found = -ENODATA, }, |
1182 | }; | |
4d20c685 | 1183 | unsigned long no_expand; |
ac27a0ec DK |
1184 | int error; |
1185 | ||
1186 | if (!name) | |
1187 | return -EINVAL; | |
1188 | if (strlen(name) > 255) | |
1189 | return -ERANGE; | |
617ba13b | 1190 | down_write(&EXT4_I(inode)->xattr_sem); |
19f5fb7a TT |
1191 | no_expand = ext4_test_inode_state(inode, EXT4_STATE_NO_EXPAND); |
1192 | ext4_set_inode_state(inode, EXT4_STATE_NO_EXPAND); | |
4d20c685 | 1193 | |
66543617 | 1194 | error = ext4_reserve_inode_write(handle, inode, &is.iloc); |
86ebfd08 ES |
1195 | if (error) |
1196 | goto cleanup; | |
1197 | ||
19f5fb7a | 1198 | if (ext4_test_inode_state(inode, EXT4_STATE_NEW)) { |
617ba13b MC |
1199 | struct ext4_inode *raw_inode = ext4_raw_inode(&is.iloc); |
1200 | memset(raw_inode, 0, EXT4_SB(inode->i_sb)->s_inode_size); | |
19f5fb7a | 1201 | ext4_clear_inode_state(inode, EXT4_STATE_NEW); |
ac27a0ec DK |
1202 | } |
1203 | ||
617ba13b | 1204 | error = ext4_xattr_ibody_find(inode, &i, &is); |
ac27a0ec DK |
1205 | if (error) |
1206 | goto cleanup; | |
1207 | if (is.s.not_found) | |
617ba13b | 1208 | error = ext4_xattr_block_find(inode, &i, &bs); |
ac27a0ec DK |
1209 | if (error) |
1210 | goto cleanup; | |
1211 | if (is.s.not_found && bs.s.not_found) { | |
1212 | error = -ENODATA; | |
1213 | if (flags & XATTR_REPLACE) | |
1214 | goto cleanup; | |
1215 | error = 0; | |
1216 | if (!value) | |
1217 | goto cleanup; | |
1218 | } else { | |
1219 | error = -EEXIST; | |
1220 | if (flags & XATTR_CREATE) | |
1221 | goto cleanup; | |
1222 | } | |
ac27a0ec DK |
1223 | if (!value) { |
1224 | if (!is.s.not_found) | |
617ba13b | 1225 | error = ext4_xattr_ibody_set(handle, inode, &i, &is); |
ac27a0ec | 1226 | else if (!bs.s.not_found) |
617ba13b | 1227 | error = ext4_xattr_block_set(handle, inode, &i, &bs); |
ac27a0ec | 1228 | } else { |
3fd16462 JK |
1229 | error = 0; |
1230 | /* Xattr value did not change? Save us some work and bail out */ | |
1231 | if (!is.s.not_found && ext4_xattr_value_same(&is.s, &i)) | |
1232 | goto cleanup; | |
1233 | if (!bs.s.not_found && ext4_xattr_value_same(&bs.s, &i)) | |
1234 | goto cleanup; | |
1235 | ||
617ba13b | 1236 | error = ext4_xattr_ibody_set(handle, inode, &i, &is); |
ac27a0ec DK |
1237 | if (!error && !bs.s.not_found) { |
1238 | i.value = NULL; | |
617ba13b | 1239 | error = ext4_xattr_block_set(handle, inode, &i, &bs); |
ac27a0ec | 1240 | } else if (error == -ENOSPC) { |
7e01c8e5 TY |
1241 | if (EXT4_I(inode)->i_file_acl && !bs.s.base) { |
1242 | error = ext4_xattr_block_find(inode, &i, &bs); | |
1243 | if (error) | |
1244 | goto cleanup; | |
1245 | } | |
617ba13b | 1246 | error = ext4_xattr_block_set(handle, inode, &i, &bs); |
ac27a0ec DK |
1247 | if (error) |
1248 | goto cleanup; | |
1249 | if (!is.s.not_found) { | |
1250 | i.value = NULL; | |
617ba13b | 1251 | error = ext4_xattr_ibody_set(handle, inode, &i, |
ac27a0ec DK |
1252 | &is); |
1253 | } | |
1254 | } | |
1255 | } | |
1256 | if (!error) { | |
617ba13b | 1257 | ext4_xattr_update_super_block(handle, inode->i_sb); |
ef7f3835 | 1258 | inode->i_ctime = ext4_current_time(inode); |
6dd4ee7c | 1259 | if (!value) |
19f5fb7a | 1260 | ext4_clear_inode_state(inode, EXT4_STATE_NO_EXPAND); |
617ba13b | 1261 | error = ext4_mark_iloc_dirty(handle, inode, &is.iloc); |
ac27a0ec | 1262 | /* |
617ba13b | 1263 | * The bh is consumed by ext4_mark_iloc_dirty, even with |
ac27a0ec DK |
1264 | * error != 0. |
1265 | */ | |
1266 | is.iloc.bh = NULL; | |
1267 | if (IS_SYNC(inode)) | |
0390131b | 1268 | ext4_handle_sync(handle); |
ac27a0ec DK |
1269 | } |
1270 | ||
1271 | cleanup: | |
1272 | brelse(is.iloc.bh); | |
1273 | brelse(bs.bh); | |
4d20c685 | 1274 | if (no_expand == 0) |
19f5fb7a | 1275 | ext4_clear_inode_state(inode, EXT4_STATE_NO_EXPAND); |
617ba13b | 1276 | up_write(&EXT4_I(inode)->xattr_sem); |
ac27a0ec DK |
1277 | return error; |
1278 | } | |
1279 | ||
1280 | /* | |
617ba13b | 1281 | * ext4_xattr_set() |
ac27a0ec | 1282 | * |
617ba13b | 1283 | * Like ext4_xattr_set_handle, but start from an inode. This extended |
ac27a0ec DK |
1284 | * attribute modification is a filesystem transaction by itself. |
1285 | * | |
1286 | * Returns 0, or a negative error number on failure. | |
1287 | */ | |
1288 | int | |
617ba13b | 1289 | ext4_xattr_set(struct inode *inode, int name_index, const char *name, |
ac27a0ec DK |
1290 | const void *value, size_t value_len, int flags) |
1291 | { | |
1292 | handle_t *handle; | |
1293 | int error, retries = 0; | |
95eaefbd | 1294 | int credits = ext4_jbd2_credits_xattr(inode); |
ac27a0ec DK |
1295 | |
1296 | retry: | |
9924a92a | 1297 | handle = ext4_journal_start(inode, EXT4_HT_XATTR, credits); |
ac27a0ec DK |
1298 | if (IS_ERR(handle)) { |
1299 | error = PTR_ERR(handle); | |
1300 | } else { | |
1301 | int error2; | |
1302 | ||
617ba13b | 1303 | error = ext4_xattr_set_handle(handle, inode, name_index, name, |
ac27a0ec | 1304 | value, value_len, flags); |
617ba13b | 1305 | error2 = ext4_journal_stop(handle); |
ac27a0ec | 1306 | if (error == -ENOSPC && |
617ba13b | 1307 | ext4_should_retry_alloc(inode->i_sb, &retries)) |
ac27a0ec DK |
1308 | goto retry; |
1309 | if (error == 0) | |
1310 | error = error2; | |
1311 | } | |
1312 | ||
1313 | return error; | |
1314 | } | |
1315 | ||
6dd4ee7c KS |
1316 | /* |
1317 | * Shift the EA entries in the inode to create space for the increased | |
1318 | * i_extra_isize. | |
1319 | */ | |
1320 | static void ext4_xattr_shift_entries(struct ext4_xattr_entry *entry, | |
1321 | int value_offs_shift, void *to, | |
94405713 | 1322 | void *from, size_t n) |
6dd4ee7c KS |
1323 | { |
1324 | struct ext4_xattr_entry *last = entry; | |
1325 | int new_offs; | |
1326 | ||
94405713 JK |
1327 | /* We always shift xattr headers further thus offsets get lower */ |
1328 | BUG_ON(value_offs_shift > 0); | |
1329 | ||
6dd4ee7c KS |
1330 | /* Adjust the value offsets of the entries */ |
1331 | for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) { | |
1cba4237 | 1332 | if (last->e_value_size) { |
6dd4ee7c KS |
1333 | new_offs = le16_to_cpu(last->e_value_offs) + |
1334 | value_offs_shift; | |
6dd4ee7c KS |
1335 | last->e_value_offs = cpu_to_le16(new_offs); |
1336 | } | |
1337 | } | |
1338 | /* Shift the entries by n bytes */ | |
1339 | memmove(to, from, n); | |
1340 | } | |
1341 | ||
3f2571c1 JK |
1342 | /* |
1343 | * Move xattr pointed to by 'entry' from inode into external xattr block | |
1344 | */ | |
1345 | static int ext4_xattr_move_to_block(handle_t *handle, struct inode *inode, | |
1346 | struct ext4_inode *raw_inode, | |
1347 | struct ext4_xattr_entry *entry) | |
1348 | { | |
1349 | struct ext4_xattr_ibody_find *is = NULL; | |
1350 | struct ext4_xattr_block_find *bs = NULL; | |
1351 | char *buffer = NULL, *b_entry_name = NULL; | |
1352 | size_t value_offs, value_size; | |
1353 | struct ext4_xattr_info i = { | |
1354 | .value = NULL, | |
1355 | .value_len = 0, | |
1356 | .name_index = entry->e_name_index, | |
1357 | }; | |
1358 | struct ext4_xattr_ibody_header *header = IHDR(inode, raw_inode); | |
1359 | int error; | |
1360 | ||
1361 | value_offs = le16_to_cpu(entry->e_value_offs); | |
1362 | value_size = le32_to_cpu(entry->e_value_size); | |
1363 | ||
1364 | is = kzalloc(sizeof(struct ext4_xattr_ibody_find), GFP_NOFS); | |
1365 | bs = kzalloc(sizeof(struct ext4_xattr_block_find), GFP_NOFS); | |
1366 | buffer = kmalloc(value_size, GFP_NOFS); | |
1367 | b_entry_name = kmalloc(entry->e_name_len + 1, GFP_NOFS); | |
1368 | if (!is || !bs || !buffer || !b_entry_name) { | |
1369 | error = -ENOMEM; | |
1370 | goto out; | |
1371 | } | |
1372 | ||
1373 | is->s.not_found = -ENODATA; | |
1374 | bs->s.not_found = -ENODATA; | |
1375 | is->iloc.bh = NULL; | |
1376 | bs->bh = NULL; | |
1377 | ||
1378 | /* Save the entry name and the entry value */ | |
1379 | memcpy(buffer, (void *)IFIRST(header) + value_offs, value_size); | |
1380 | memcpy(b_entry_name, entry->e_name, entry->e_name_len); | |
1381 | b_entry_name[entry->e_name_len] = '\0'; | |
1382 | i.name = b_entry_name; | |
1383 | ||
1384 | error = ext4_get_inode_loc(inode, &is->iloc); | |
1385 | if (error) | |
1386 | goto out; | |
1387 | ||
1388 | error = ext4_xattr_ibody_find(inode, &i, is); | |
1389 | if (error) | |
1390 | goto out; | |
1391 | ||
1392 | /* Remove the chosen entry from the inode */ | |
1393 | error = ext4_xattr_ibody_set(handle, inode, &i, is); | |
1394 | if (error) | |
1395 | goto out; | |
1396 | ||
1397 | i.name = b_entry_name; | |
1398 | i.value = buffer; | |
1399 | i.value_len = value_size; | |
1400 | error = ext4_xattr_block_find(inode, &i, bs); | |
1401 | if (error) | |
1402 | goto out; | |
1403 | ||
1404 | /* Add entry which was removed from the inode into the block */ | |
1405 | error = ext4_xattr_block_set(handle, inode, &i, bs); | |
1406 | if (error) | |
1407 | goto out; | |
1408 | error = 0; | |
1409 | out: | |
1410 | kfree(b_entry_name); | |
1411 | kfree(buffer); | |
1412 | if (is) | |
1413 | brelse(is->iloc.bh); | |
1414 | kfree(is); | |
1415 | kfree(bs); | |
1416 | ||
1417 | return error; | |
1418 | } | |
1419 | ||
6dd4ee7c KS |
1420 | /* |
1421 | * Expand an inode by new_extra_isize bytes when EAs are present. | |
1422 | * Returns 0 on success or negative error number on failure. | |
1423 | */ | |
1424 | int ext4_expand_extra_isize_ea(struct inode *inode, int new_extra_isize, | |
1425 | struct ext4_inode *raw_inode, handle_t *handle) | |
1426 | { | |
1427 | struct ext4_xattr_ibody_header *header; | |
1428 | struct ext4_xattr_entry *entry, *last, *first; | |
1429 | struct buffer_head *bh = NULL; | |
e3014d14 JK |
1430 | size_t min_offs; |
1431 | size_t ifree, bfree; | |
7b1b2c1b | 1432 | int total_ino; |
6dd4ee7c | 1433 | void *base, *start, *end; |
d0141191 | 1434 | int error = 0, tried_min_extra_isize = 0; |
ac39849d | 1435 | int s_min_extra_isize = le16_to_cpu(EXT4_SB(inode->i_sb)->s_es->s_min_extra_isize); |
d0141191 | 1436 | int isize_diff; /* How much do we need to grow i_extra_isize */ |
6dd4ee7c KS |
1437 | |
1438 | down_write(&EXT4_I(inode)->xattr_sem); | |
2e81a4ee JK |
1439 | /* |
1440 | * Set EXT4_STATE_NO_EXPAND to avoid recursion when marking inode dirty | |
1441 | */ | |
1442 | ext4_set_inode_state(inode, EXT4_STATE_NO_EXPAND); | |
6dd4ee7c | 1443 | retry: |
d0141191 | 1444 | isize_diff = new_extra_isize - EXT4_I(inode)->i_extra_isize; |
2e81a4ee JK |
1445 | if (EXT4_I(inode)->i_extra_isize >= new_extra_isize) |
1446 | goto out; | |
6dd4ee7c KS |
1447 | |
1448 | header = IHDR(inode, raw_inode); | |
1449 | entry = IFIRST(header); | |
1450 | ||
1451 | /* | |
1452 | * Check if enough free space is available in the inode to shift the | |
1453 | * entries ahead by new_extra_isize. | |
1454 | */ | |
1455 | ||
1456 | base = start = entry; | |
1457 | end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; | |
1458 | min_offs = end - base; | |
1459 | last = entry; | |
1460 | total_ino = sizeof(struct ext4_xattr_ibody_header); | |
1461 | ||
9e92f48c TT |
1462 | error = xattr_check_inode(inode, header, end); |
1463 | if (error) | |
1464 | goto cleanup; | |
1465 | ||
e3014d14 JK |
1466 | ifree = ext4_xattr_free_space(last, &min_offs, base, &total_ino); |
1467 | if (ifree >= isize_diff) | |
1468 | goto shift; | |
6dd4ee7c KS |
1469 | |
1470 | /* | |
1471 | * Enough free space isn't available in the inode, check if | |
1472 | * EA block can hold new_extra_isize bytes. | |
1473 | */ | |
1474 | if (EXT4_I(inode)->i_file_acl) { | |
1475 | bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl); | |
1476 | error = -EIO; | |
1477 | if (!bh) | |
1478 | goto cleanup; | |
cc8e94fd | 1479 | if (ext4_xattr_check_block(inode, bh)) { |
24676da4 TT |
1480 | EXT4_ERROR_INODE(inode, "bad block %llu", |
1481 | EXT4_I(inode)->i_file_acl); | |
6a797d27 | 1482 | error = -EFSCORRUPTED; |
6dd4ee7c KS |
1483 | goto cleanup; |
1484 | } | |
1485 | base = BHDR(bh); | |
1486 | first = BFIRST(bh); | |
1487 | end = bh->b_data + bh->b_size; | |
1488 | min_offs = end - base; | |
e3014d14 JK |
1489 | bfree = ext4_xattr_free_space(first, &min_offs, base, NULL); |
1490 | if (bfree + ifree < isize_diff) { | |
6dd4ee7c KS |
1491 | if (!tried_min_extra_isize && s_min_extra_isize) { |
1492 | tried_min_extra_isize++; | |
1493 | new_extra_isize = s_min_extra_isize; | |
1494 | brelse(bh); | |
1495 | goto retry; | |
1496 | } | |
1497 | error = -1; | |
1498 | goto cleanup; | |
1499 | } | |
1500 | } else { | |
e3014d14 | 1501 | bfree = inode->i_sb->s_blocksize; |
6dd4ee7c KS |
1502 | } |
1503 | ||
e3014d14 | 1504 | while (isize_diff > ifree) { |
6dd4ee7c | 1505 | struct ext4_xattr_entry *small_entry = NULL; |
3f2571c1 JK |
1506 | unsigned int entry_size; /* EA entry size */ |
1507 | unsigned int total_size; /* EA entry size + value size */ | |
6dd4ee7c KS |
1508 | unsigned int min_total_size = ~0U; |
1509 | ||
6dd4ee7c KS |
1510 | last = IFIRST(header); |
1511 | /* Find the entry best suited to be pushed into EA block */ | |
1512 | entry = NULL; | |
1513 | for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) { | |
1514 | total_size = | |
1515 | EXT4_XATTR_SIZE(le32_to_cpu(last->e_value_size)) + | |
1516 | EXT4_XATTR_LEN(last->e_name_len); | |
e3014d14 JK |
1517 | if (total_size <= bfree && |
1518 | total_size < min_total_size) { | |
1519 | if (total_size + ifree < isize_diff) { | |
6dd4ee7c KS |
1520 | small_entry = last; |
1521 | } else { | |
1522 | entry = last; | |
1523 | min_total_size = total_size; | |
1524 | } | |
1525 | } | |
1526 | } | |
1527 | ||
1528 | if (entry == NULL) { | |
1529 | if (small_entry) { | |
1530 | entry = small_entry; | |
1531 | } else { | |
1532 | if (!tried_min_extra_isize && | |
1533 | s_min_extra_isize) { | |
1534 | tried_min_extra_isize++; | |
1535 | new_extra_isize = s_min_extra_isize; | |
dcb9917b | 1536 | brelse(bh); |
6dd4ee7c KS |
1537 | goto retry; |
1538 | } | |
1539 | error = -1; | |
1540 | goto cleanup; | |
1541 | } | |
1542 | } | |
6dd4ee7c | 1543 | |
3f2571c1 JK |
1544 | entry_size = EXT4_XATTR_LEN(entry->e_name_len); |
1545 | total_size = entry_size + | |
1546 | EXT4_XATTR_SIZE(le32_to_cpu(entry->e_value_size)); | |
1547 | error = ext4_xattr_move_to_block(handle, inode, raw_inode, | |
1548 | entry); | |
6dd4ee7c KS |
1549 | if (error) |
1550 | goto cleanup; | |
1551 | ||
418c12d0 | 1552 | total_ino -= entry_size; |
e3014d14 JK |
1553 | ifree += total_size; |
1554 | bfree -= total_size; | |
6dd4ee7c | 1555 | } |
e3014d14 JK |
1556 | |
1557 | shift: | |
1558 | /* Adjust the offsets and shift the remaining entries ahead */ | |
1559 | entry = IFIRST(header); | |
1560 | ext4_xattr_shift_entries(entry, EXT4_I(inode)->i_extra_isize | |
1561 | - new_extra_isize, (void *)raw_inode + | |
1562 | EXT4_GOOD_OLD_INODE_SIZE + new_extra_isize, | |
94405713 | 1563 | (void *)header, total_ino); |
e3014d14 | 1564 | EXT4_I(inode)->i_extra_isize = new_extra_isize; |
6dd4ee7c | 1565 | brelse(bh); |
2e81a4ee JK |
1566 | out: |
1567 | ext4_clear_inode_state(inode, EXT4_STATE_NO_EXPAND); | |
6dd4ee7c KS |
1568 | up_write(&EXT4_I(inode)->xattr_sem); |
1569 | return 0; | |
1570 | ||
1571 | cleanup: | |
6dd4ee7c | 1572 | brelse(bh); |
2e81a4ee JK |
1573 | /* |
1574 | * We deliberately leave EXT4_STATE_NO_EXPAND set here since inode | |
1575 | * size expansion failed. | |
1576 | */ | |
6dd4ee7c KS |
1577 | up_write(&EXT4_I(inode)->xattr_sem); |
1578 | return error; | |
1579 | } | |
1580 | ||
1581 | ||
1582 | ||
ac27a0ec | 1583 | /* |
617ba13b | 1584 | * ext4_xattr_delete_inode() |
ac27a0ec DK |
1585 | * |
1586 | * Free extended attribute resources associated with this inode. This | |
1587 | * is called immediately before an inode is freed. We have exclusive | |
1588 | * access to the inode. | |
1589 | */ | |
1590 | void | |
617ba13b | 1591 | ext4_xattr_delete_inode(handle_t *handle, struct inode *inode) |
ac27a0ec DK |
1592 | { |
1593 | struct buffer_head *bh = NULL; | |
1594 | ||
617ba13b | 1595 | if (!EXT4_I(inode)->i_file_acl) |
ac27a0ec | 1596 | goto cleanup; |
617ba13b | 1597 | bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl); |
ac27a0ec | 1598 | if (!bh) { |
24676da4 TT |
1599 | EXT4_ERROR_INODE(inode, "block %llu read error", |
1600 | EXT4_I(inode)->i_file_acl); | |
ac27a0ec DK |
1601 | goto cleanup; |
1602 | } | |
617ba13b | 1603 | if (BHDR(bh)->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC) || |
ac27a0ec | 1604 | BHDR(bh)->h_blocks != cpu_to_le32(1)) { |
24676da4 TT |
1605 | EXT4_ERROR_INODE(inode, "bad block %llu", |
1606 | EXT4_I(inode)->i_file_acl); | |
ac27a0ec DK |
1607 | goto cleanup; |
1608 | } | |
617ba13b MC |
1609 | ext4_xattr_release_block(handle, inode, bh); |
1610 | EXT4_I(inode)->i_file_acl = 0; | |
ac27a0ec DK |
1611 | |
1612 | cleanup: | |
1613 | brelse(bh); | |
1614 | } | |
1615 | ||
ac27a0ec | 1616 | /* |
617ba13b | 1617 | * ext4_xattr_cache_insert() |
ac27a0ec DK |
1618 | * |
1619 | * Create a new entry in the extended attribute cache, and insert | |
1620 | * it unless such an entry is already in the cache. | |
1621 | * | |
1622 | * Returns 0, or a negative error number on failure. | |
1623 | */ | |
1624 | static void | |
7a2508e1 | 1625 | ext4_xattr_cache_insert(struct mb_cache *ext4_mb_cache, struct buffer_head *bh) |
ac27a0ec | 1626 | { |
6048c64b AG |
1627 | struct ext4_xattr_header *header = BHDR(bh); |
1628 | __u32 hash = le32_to_cpu(header->h_hash); | |
1629 | int reusable = le32_to_cpu(header->h_refcount) < | |
1630 | EXT4_XATTR_REFCOUNT_MAX; | |
ac27a0ec DK |
1631 | int error; |
1632 | ||
7a2508e1 | 1633 | error = mb_cache_entry_create(ext4_mb_cache, GFP_NOFS, hash, |
6048c64b | 1634 | bh->b_blocknr, reusable); |
ac27a0ec | 1635 | if (error) { |
82939d79 | 1636 | if (error == -EBUSY) |
ac27a0ec | 1637 | ea_bdebug(bh, "already in cache"); |
82939d79 | 1638 | } else |
ac27a0ec | 1639 | ea_bdebug(bh, "inserting [%x]", (int)hash); |
ac27a0ec DK |
1640 | } |
1641 | ||
1642 | /* | |
617ba13b | 1643 | * ext4_xattr_cmp() |
ac27a0ec DK |
1644 | * |
1645 | * Compare two extended attribute blocks for equality. | |
1646 | * | |
1647 | * Returns 0 if the blocks are equal, 1 if they differ, and | |
1648 | * a negative error number on errors. | |
1649 | */ | |
1650 | static int | |
617ba13b MC |
1651 | ext4_xattr_cmp(struct ext4_xattr_header *header1, |
1652 | struct ext4_xattr_header *header2) | |
ac27a0ec | 1653 | { |
617ba13b | 1654 | struct ext4_xattr_entry *entry1, *entry2; |
ac27a0ec DK |
1655 | |
1656 | entry1 = ENTRY(header1+1); | |
1657 | entry2 = ENTRY(header2+1); | |
1658 | while (!IS_LAST_ENTRY(entry1)) { | |
1659 | if (IS_LAST_ENTRY(entry2)) | |
1660 | return 1; | |
1661 | if (entry1->e_hash != entry2->e_hash || | |
1662 | entry1->e_name_index != entry2->e_name_index || | |
1663 | entry1->e_name_len != entry2->e_name_len || | |
1664 | entry1->e_value_size != entry2->e_value_size || | |
1665 | memcmp(entry1->e_name, entry2->e_name, entry1->e_name_len)) | |
1666 | return 1; | |
1667 | if (entry1->e_value_block != 0 || entry2->e_value_block != 0) | |
6a797d27 | 1668 | return -EFSCORRUPTED; |
ac27a0ec DK |
1669 | if (memcmp((char *)header1 + le16_to_cpu(entry1->e_value_offs), |
1670 | (char *)header2 + le16_to_cpu(entry2->e_value_offs), | |
1671 | le32_to_cpu(entry1->e_value_size))) | |
1672 | return 1; | |
1673 | ||
617ba13b MC |
1674 | entry1 = EXT4_XATTR_NEXT(entry1); |
1675 | entry2 = EXT4_XATTR_NEXT(entry2); | |
ac27a0ec DK |
1676 | } |
1677 | if (!IS_LAST_ENTRY(entry2)) | |
1678 | return 1; | |
1679 | return 0; | |
1680 | } | |
1681 | ||
1682 | /* | |
617ba13b | 1683 | * ext4_xattr_cache_find() |
ac27a0ec DK |
1684 | * |
1685 | * Find an identical extended attribute block. | |
1686 | * | |
1687 | * Returns a pointer to the block found, or NULL if such a block was | |
1688 | * not found or an error occurred. | |
1689 | */ | |
1690 | static struct buffer_head * | |
617ba13b | 1691 | ext4_xattr_cache_find(struct inode *inode, struct ext4_xattr_header *header, |
7a2508e1 | 1692 | struct mb_cache_entry **pce) |
ac27a0ec DK |
1693 | { |
1694 | __u32 hash = le32_to_cpu(header->h_hash); | |
7a2508e1 JK |
1695 | struct mb_cache_entry *ce; |
1696 | struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode); | |
ac27a0ec DK |
1697 | |
1698 | if (!header->h_hash) | |
1699 | return NULL; /* never share */ | |
1700 | ea_idebug(inode, "looking for cached blocks [%x]", (int)hash); | |
7a2508e1 | 1701 | ce = mb_cache_entry_find_first(ext4_mb_cache, hash); |
ac27a0ec DK |
1702 | while (ce) { |
1703 | struct buffer_head *bh; | |
1704 | ||
ac27a0ec DK |
1705 | bh = sb_bread(inode->i_sb, ce->e_block); |
1706 | if (!bh) { | |
24676da4 TT |
1707 | EXT4_ERROR_INODE(inode, "block %lu read error", |
1708 | (unsigned long) ce->e_block); | |
617ba13b | 1709 | } else if (ext4_xattr_cmp(header, BHDR(bh)) == 0) { |
ac27a0ec DK |
1710 | *pce = ce; |
1711 | return bh; | |
1712 | } | |
1713 | brelse(bh); | |
7a2508e1 | 1714 | ce = mb_cache_entry_find_next(ext4_mb_cache, ce); |
ac27a0ec DK |
1715 | } |
1716 | return NULL; | |
1717 | } | |
1718 | ||
1719 | #define NAME_HASH_SHIFT 5 | |
1720 | #define VALUE_HASH_SHIFT 16 | |
1721 | ||
1722 | /* | |
617ba13b | 1723 | * ext4_xattr_hash_entry() |
ac27a0ec DK |
1724 | * |
1725 | * Compute the hash of an extended attribute. | |
1726 | */ | |
617ba13b MC |
1727 | static inline void ext4_xattr_hash_entry(struct ext4_xattr_header *header, |
1728 | struct ext4_xattr_entry *entry) | |
ac27a0ec DK |
1729 | { |
1730 | __u32 hash = 0; | |
1731 | char *name = entry->e_name; | |
1732 | int n; | |
1733 | ||
2b2d6d01 | 1734 | for (n = 0; n < entry->e_name_len; n++) { |
ac27a0ec DK |
1735 | hash = (hash << NAME_HASH_SHIFT) ^ |
1736 | (hash >> (8*sizeof(hash) - NAME_HASH_SHIFT)) ^ | |
1737 | *name++; | |
1738 | } | |
1739 | ||
1cba4237 | 1740 | if (entry->e_value_size != 0) { |
ac27a0ec DK |
1741 | __le32 *value = (__le32 *)((char *)header + |
1742 | le16_to_cpu(entry->e_value_offs)); | |
1743 | for (n = (le32_to_cpu(entry->e_value_size) + | |
617ba13b | 1744 | EXT4_XATTR_ROUND) >> EXT4_XATTR_PAD_BITS; n; n--) { |
ac27a0ec DK |
1745 | hash = (hash << VALUE_HASH_SHIFT) ^ |
1746 | (hash >> (8*sizeof(hash) - VALUE_HASH_SHIFT)) ^ | |
1747 | le32_to_cpu(*value++); | |
1748 | } | |
1749 | } | |
1750 | entry->e_hash = cpu_to_le32(hash); | |
1751 | } | |
1752 | ||
1753 | #undef NAME_HASH_SHIFT | |
1754 | #undef VALUE_HASH_SHIFT | |
1755 | ||
1756 | #define BLOCK_HASH_SHIFT 16 | |
1757 | ||
1758 | /* | |
617ba13b | 1759 | * ext4_xattr_rehash() |
ac27a0ec DK |
1760 | * |
1761 | * Re-compute the extended attribute hash value after an entry has changed. | |
1762 | */ | |
617ba13b MC |
1763 | static void ext4_xattr_rehash(struct ext4_xattr_header *header, |
1764 | struct ext4_xattr_entry *entry) | |
ac27a0ec | 1765 | { |
617ba13b | 1766 | struct ext4_xattr_entry *here; |
ac27a0ec DK |
1767 | __u32 hash = 0; |
1768 | ||
617ba13b | 1769 | ext4_xattr_hash_entry(header, entry); |
ac27a0ec DK |
1770 | here = ENTRY(header+1); |
1771 | while (!IS_LAST_ENTRY(here)) { | |
1772 | if (!here->e_hash) { | |
1773 | /* Block is not shared if an entry's hash value == 0 */ | |
1774 | hash = 0; | |
1775 | break; | |
1776 | } | |
1777 | hash = (hash << BLOCK_HASH_SHIFT) ^ | |
1778 | (hash >> (8*sizeof(hash) - BLOCK_HASH_SHIFT)) ^ | |
1779 | le32_to_cpu(here->e_hash); | |
617ba13b | 1780 | here = EXT4_XATTR_NEXT(here); |
ac27a0ec DK |
1781 | } |
1782 | header->h_hash = cpu_to_le32(hash); | |
1783 | } | |
1784 | ||
1785 | #undef BLOCK_HASH_SHIFT | |
1786 | ||
9c191f70 M |
1787 | #define HASH_BUCKET_BITS 10 |
1788 | ||
7a2508e1 | 1789 | struct mb_cache * |
82939d79 | 1790 | ext4_xattr_create_cache(void) |
ac27a0ec | 1791 | { |
7a2508e1 | 1792 | return mb_cache_create(HASH_BUCKET_BITS); |
ac27a0ec DK |
1793 | } |
1794 | ||
7a2508e1 | 1795 | void ext4_xattr_destroy_cache(struct mb_cache *cache) |
ac27a0ec | 1796 | { |
9c191f70 | 1797 | if (cache) |
7a2508e1 | 1798 | mb_cache_destroy(cache); |
ac27a0ec | 1799 | } |
9c191f70 | 1800 |