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> | |
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 |
d74f3d25 JP |
64 | # define ea_idebug(inode, fmt, ...) \ |
65 | printk(KERN_DEBUG "inode %s:%lu: " fmt "\n", \ | |
66 | inode->i_sb->s_id, inode->i_ino, ##__VA_ARGS__) | |
67 | # define ea_bdebug(bh, fmt, ...) \ | |
68 | printk(KERN_DEBUG "block %pg:%lu: " fmt "\n", \ | |
69 | bh->b_bdev, (unsigned long)bh->b_blocknr, ##__VA_ARGS__) | |
ac27a0ec | 70 | #else |
ace36ad4 JP |
71 | # define ea_idebug(inode, fmt, ...) no_printk(fmt, ##__VA_ARGS__) |
72 | # define ea_bdebug(bh, fmt, ...) no_printk(fmt, ##__VA_ARGS__) | |
ac27a0ec DK |
73 | #endif |
74 | ||
7a2508e1 | 75 | static void ext4_xattr_cache_insert(struct mb_cache *, struct buffer_head *); |
617ba13b MC |
76 | static struct buffer_head *ext4_xattr_cache_find(struct inode *, |
77 | struct ext4_xattr_header *, | |
7a2508e1 | 78 | struct mb_cache_entry **); |
617ba13b MC |
79 | static void ext4_xattr_rehash(struct ext4_xattr_header *, |
80 | struct ext4_xattr_entry *); | |
431547b3 | 81 | static int ext4_xattr_list(struct dentry *dentry, char *buffer, |
d3a95d47 | 82 | size_t buffer_size); |
ac27a0ec | 83 | |
11e27528 | 84 | static const struct xattr_handler *ext4_xattr_handler_map[] = { |
617ba13b | 85 | [EXT4_XATTR_INDEX_USER] = &ext4_xattr_user_handler, |
03010a33 | 86 | #ifdef CONFIG_EXT4_FS_POSIX_ACL |
64e178a7 CH |
87 | [EXT4_XATTR_INDEX_POSIX_ACL_ACCESS] = &posix_acl_access_xattr_handler, |
88 | [EXT4_XATTR_INDEX_POSIX_ACL_DEFAULT] = &posix_acl_default_xattr_handler, | |
ac27a0ec | 89 | #endif |
617ba13b | 90 | [EXT4_XATTR_INDEX_TRUSTED] = &ext4_xattr_trusted_handler, |
03010a33 | 91 | #ifdef CONFIG_EXT4_FS_SECURITY |
617ba13b | 92 | [EXT4_XATTR_INDEX_SECURITY] = &ext4_xattr_security_handler, |
ac27a0ec DK |
93 | #endif |
94 | }; | |
95 | ||
11e27528 | 96 | const struct xattr_handler *ext4_xattr_handlers[] = { |
617ba13b MC |
97 | &ext4_xattr_user_handler, |
98 | &ext4_xattr_trusted_handler, | |
03010a33 | 99 | #ifdef CONFIG_EXT4_FS_POSIX_ACL |
64e178a7 CH |
100 | &posix_acl_access_xattr_handler, |
101 | &posix_acl_default_xattr_handler, | |
ac27a0ec | 102 | #endif |
03010a33 | 103 | #ifdef CONFIG_EXT4_FS_SECURITY |
617ba13b | 104 | &ext4_xattr_security_handler, |
ac27a0ec DK |
105 | #endif |
106 | NULL | |
107 | }; | |
108 | ||
9c191f70 M |
109 | #define EXT4_GET_MB_CACHE(inode) (((struct ext4_sb_info *) \ |
110 | inode->i_sb->s_fs_info)->s_mb_cache) | |
111 | ||
cc8e94fd DW |
112 | static __le32 ext4_xattr_block_csum(struct inode *inode, |
113 | sector_t block_nr, | |
114 | struct ext4_xattr_header *hdr) | |
115 | { | |
116 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); | |
d6a77105 | 117 | __u32 csum; |
d6a77105 | 118 | __le64 dsk_block_nr = cpu_to_le64(block_nr); |
b47820ed DJ |
119 | __u32 dummy_csum = 0; |
120 | int offset = offsetof(struct ext4_xattr_header, h_checksum); | |
cc8e94fd | 121 | |
d6a77105 TT |
122 | csum = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&dsk_block_nr, |
123 | sizeof(dsk_block_nr)); | |
b47820ed DJ |
124 | csum = ext4_chksum(sbi, csum, (__u8 *)hdr, offset); |
125 | csum = ext4_chksum(sbi, csum, (__u8 *)&dummy_csum, sizeof(dummy_csum)); | |
126 | offset += sizeof(dummy_csum); | |
127 | csum = ext4_chksum(sbi, csum, (__u8 *)hdr + offset, | |
128 | EXT4_BLOCK_SIZE(inode->i_sb) - offset); | |
41eb70dd | 129 | |
cc8e94fd DW |
130 | return cpu_to_le32(csum); |
131 | } | |
132 | ||
133 | static int ext4_xattr_block_csum_verify(struct inode *inode, | |
134 | sector_t block_nr, | |
135 | struct ext4_xattr_header *hdr) | |
136 | { | |
9aa5d32b | 137 | if (ext4_has_metadata_csum(inode->i_sb) && |
cc8e94fd DW |
138 | (hdr->h_checksum != ext4_xattr_block_csum(inode, block_nr, hdr))) |
139 | return 0; | |
140 | return 1; | |
141 | } | |
142 | ||
143 | static void ext4_xattr_block_csum_set(struct inode *inode, | |
144 | sector_t block_nr, | |
145 | struct ext4_xattr_header *hdr) | |
146 | { | |
9aa5d32b | 147 | if (!ext4_has_metadata_csum(inode->i_sb)) |
cc8e94fd DW |
148 | return; |
149 | ||
150 | hdr->h_checksum = ext4_xattr_block_csum(inode, block_nr, hdr); | |
151 | } | |
152 | ||
153 | static inline int ext4_handle_dirty_xattr_block(handle_t *handle, | |
154 | struct inode *inode, | |
155 | struct buffer_head *bh) | |
156 | { | |
157 | ext4_xattr_block_csum_set(inode, bh->b_blocknr, BHDR(bh)); | |
158 | return ext4_handle_dirty_metadata(handle, inode, bh); | |
159 | } | |
160 | ||
11e27528 | 161 | static inline const struct xattr_handler * |
617ba13b | 162 | ext4_xattr_handler(int name_index) |
ac27a0ec | 163 | { |
11e27528 | 164 | const struct xattr_handler *handler = NULL; |
ac27a0ec | 165 | |
617ba13b MC |
166 | if (name_index > 0 && name_index < ARRAY_SIZE(ext4_xattr_handler_map)) |
167 | handler = ext4_xattr_handler_map[name_index]; | |
ac27a0ec DK |
168 | return handler; |
169 | } | |
170 | ||
171 | /* | |
172 | * Inode operation listxattr() | |
173 | * | |
2b0143b5 | 174 | * d_inode(dentry)->i_mutex: don't care |
ac27a0ec DK |
175 | */ |
176 | ssize_t | |
617ba13b | 177 | ext4_listxattr(struct dentry *dentry, char *buffer, size_t size) |
ac27a0ec | 178 | { |
431547b3 | 179 | return ext4_xattr_list(dentry, buffer, size); |
ac27a0ec DK |
180 | } |
181 | ||
182 | static int | |
a0626e75 DW |
183 | ext4_xattr_check_names(struct ext4_xattr_entry *entry, void *end, |
184 | void *value_start) | |
ac27a0ec | 185 | { |
a0626e75 DW |
186 | struct ext4_xattr_entry *e = entry; |
187 | ||
188 | while (!IS_LAST_ENTRY(e)) { | |
189 | struct ext4_xattr_entry *next = EXT4_XATTR_NEXT(e); | |
ac27a0ec | 190 | if ((void *)next >= end) |
6a797d27 | 191 | return -EFSCORRUPTED; |
a0626e75 | 192 | e = next; |
ac27a0ec | 193 | } |
a0626e75 DW |
194 | |
195 | while (!IS_LAST_ENTRY(entry)) { | |
2de58f11 JK |
196 | if (entry->e_value_block != 0) |
197 | return -EFSCORRUPTED; | |
a0626e75 DW |
198 | if (entry->e_value_size != 0 && |
199 | (value_start + le16_to_cpu(entry->e_value_offs) < | |
200 | (void *)e + sizeof(__u32) || | |
201 | value_start + le16_to_cpu(entry->e_value_offs) + | |
202 | le32_to_cpu(entry->e_value_size) > end)) | |
6a797d27 | 203 | return -EFSCORRUPTED; |
a0626e75 DW |
204 | entry = EXT4_XATTR_NEXT(entry); |
205 | } | |
206 | ||
ac27a0ec DK |
207 | return 0; |
208 | } | |
209 | ||
210 | static inline int | |
cc8e94fd | 211 | ext4_xattr_check_block(struct inode *inode, struct buffer_head *bh) |
ac27a0ec | 212 | { |
cc8e94fd DW |
213 | int error; |
214 | ||
215 | if (buffer_verified(bh)) | |
216 | return 0; | |
217 | ||
617ba13b | 218 | if (BHDR(bh)->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC) || |
ac27a0ec | 219 | BHDR(bh)->h_blocks != cpu_to_le32(1)) |
6a797d27 | 220 | return -EFSCORRUPTED; |
cc8e94fd | 221 | if (!ext4_xattr_block_csum_verify(inode, bh->b_blocknr, BHDR(bh))) |
6a797d27 | 222 | return -EFSBADCRC; |
a0626e75 DW |
223 | error = ext4_xattr_check_names(BFIRST(bh), bh->b_data + bh->b_size, |
224 | bh->b_data); | |
cc8e94fd DW |
225 | if (!error) |
226 | set_buffer_verified(bh); | |
227 | return error; | |
ac27a0ec DK |
228 | } |
229 | ||
9e92f48c TT |
230 | static int |
231 | __xattr_check_inode(struct inode *inode, struct ext4_xattr_ibody_header *header, | |
232 | void *end, const char *function, unsigned int line) | |
233 | { | |
9e92f48c TT |
234 | int error = -EFSCORRUPTED; |
235 | ||
290ab230 | 236 | if (end - (void *)header < sizeof(*header) + sizeof(u32) || |
19962509 | 237 | (header->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC))) |
9e92f48c | 238 | goto errout; |
290ab230 | 239 | error = ext4_xattr_check_names(IFIRST(header), end, IFIRST(header)); |
9e92f48c TT |
240 | errout: |
241 | if (error) | |
242 | __ext4_error_inode(inode, function, line, 0, | |
243 | "corrupted in-inode xattr"); | |
244 | return error; | |
245 | } | |
246 | ||
247 | #define xattr_check_inode(inode, header, end) \ | |
248 | __xattr_check_inode((inode), (header), (end), __func__, __LINE__) | |
249 | ||
ac27a0ec | 250 | static inline int |
617ba13b | 251 | ext4_xattr_check_entry(struct ext4_xattr_entry *entry, size_t size) |
ac27a0ec DK |
252 | { |
253 | size_t value_size = le32_to_cpu(entry->e_value_size); | |
254 | ||
255 | if (entry->e_value_block != 0 || value_size > size || | |
256 | le16_to_cpu(entry->e_value_offs) + value_size > size) | |
6a797d27 | 257 | return -EFSCORRUPTED; |
ac27a0ec DK |
258 | return 0; |
259 | } | |
260 | ||
261 | static int | |
617ba13b | 262 | ext4_xattr_find_entry(struct ext4_xattr_entry **pentry, int name_index, |
ac27a0ec DK |
263 | const char *name, size_t size, int sorted) |
264 | { | |
617ba13b | 265 | struct ext4_xattr_entry *entry; |
ac27a0ec DK |
266 | size_t name_len; |
267 | int cmp = 1; | |
268 | ||
269 | if (name == NULL) | |
270 | return -EINVAL; | |
271 | name_len = strlen(name); | |
272 | entry = *pentry; | |
617ba13b | 273 | for (; !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) { |
ac27a0ec DK |
274 | cmp = name_index - entry->e_name_index; |
275 | if (!cmp) | |
276 | cmp = name_len - entry->e_name_len; | |
277 | if (!cmp) | |
278 | cmp = memcmp(name, entry->e_name, name_len); | |
279 | if (cmp <= 0 && (sorted || cmp == 0)) | |
280 | break; | |
281 | } | |
282 | *pentry = entry; | |
617ba13b | 283 | if (!cmp && ext4_xattr_check_entry(entry, size)) |
6a797d27 | 284 | return -EFSCORRUPTED; |
ac27a0ec DK |
285 | return cmp ? -ENODATA : 0; |
286 | } | |
287 | ||
288 | static int | |
617ba13b | 289 | ext4_xattr_block_get(struct inode *inode, int name_index, const char *name, |
ac27a0ec DK |
290 | void *buffer, size_t buffer_size) |
291 | { | |
292 | struct buffer_head *bh = NULL; | |
617ba13b | 293 | struct ext4_xattr_entry *entry; |
ac27a0ec DK |
294 | size_t size; |
295 | int error; | |
7a2508e1 | 296 | struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode); |
ac27a0ec DK |
297 | |
298 | ea_idebug(inode, "name=%d.%s, buffer=%p, buffer_size=%ld", | |
299 | name_index, name, buffer, (long)buffer_size); | |
300 | ||
301 | error = -ENODATA; | |
617ba13b | 302 | if (!EXT4_I(inode)->i_file_acl) |
ac27a0ec | 303 | goto cleanup; |
ace36ad4 JP |
304 | ea_idebug(inode, "reading block %llu", |
305 | (unsigned long long)EXT4_I(inode)->i_file_acl); | |
617ba13b | 306 | bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl); |
ac27a0ec DK |
307 | if (!bh) |
308 | goto cleanup; | |
309 | ea_bdebug(bh, "b_count=%d, refcount=%d", | |
310 | atomic_read(&(bh->b_count)), le32_to_cpu(BHDR(bh)->h_refcount)); | |
cc8e94fd | 311 | if (ext4_xattr_check_block(inode, bh)) { |
12062ddd | 312 | bad_block: |
24676da4 TT |
313 | EXT4_ERROR_INODE(inode, "bad block %llu", |
314 | EXT4_I(inode)->i_file_acl); | |
6a797d27 | 315 | error = -EFSCORRUPTED; |
ac27a0ec DK |
316 | goto cleanup; |
317 | } | |
9c191f70 | 318 | ext4_xattr_cache_insert(ext4_mb_cache, bh); |
ac27a0ec | 319 | entry = BFIRST(bh); |
617ba13b | 320 | error = ext4_xattr_find_entry(&entry, name_index, name, bh->b_size, 1); |
6a797d27 | 321 | if (error == -EFSCORRUPTED) |
ac27a0ec DK |
322 | goto bad_block; |
323 | if (error) | |
324 | goto cleanup; | |
325 | size = le32_to_cpu(entry->e_value_size); | |
326 | if (buffer) { | |
327 | error = -ERANGE; | |
328 | if (size > buffer_size) | |
329 | goto cleanup; | |
330 | memcpy(buffer, bh->b_data + le16_to_cpu(entry->e_value_offs), | |
331 | size); | |
332 | } | |
333 | error = size; | |
334 | ||
335 | cleanup: | |
336 | brelse(bh); | |
337 | return error; | |
338 | } | |
339 | ||
879b3825 | 340 | int |
617ba13b | 341 | ext4_xattr_ibody_get(struct inode *inode, int name_index, const char *name, |
ac27a0ec DK |
342 | void *buffer, size_t buffer_size) |
343 | { | |
617ba13b MC |
344 | struct ext4_xattr_ibody_header *header; |
345 | struct ext4_xattr_entry *entry; | |
346 | struct ext4_inode *raw_inode; | |
347 | struct ext4_iloc iloc; | |
ac27a0ec DK |
348 | size_t size; |
349 | void *end; | |
350 | int error; | |
351 | ||
19f5fb7a | 352 | if (!ext4_test_inode_state(inode, EXT4_STATE_XATTR)) |
ac27a0ec | 353 | return -ENODATA; |
617ba13b | 354 | error = ext4_get_inode_loc(inode, &iloc); |
ac27a0ec DK |
355 | if (error) |
356 | return error; | |
617ba13b | 357 | raw_inode = ext4_raw_inode(&iloc); |
ac27a0ec DK |
358 | header = IHDR(inode, raw_inode); |
359 | entry = IFIRST(header); | |
617ba13b | 360 | end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; |
9e92f48c | 361 | error = xattr_check_inode(inode, header, end); |
ac27a0ec DK |
362 | if (error) |
363 | goto cleanup; | |
617ba13b | 364 | error = ext4_xattr_find_entry(&entry, name_index, name, |
ac27a0ec DK |
365 | end - (void *)entry, 0); |
366 | if (error) | |
367 | goto cleanup; | |
368 | size = le32_to_cpu(entry->e_value_size); | |
369 | if (buffer) { | |
370 | error = -ERANGE; | |
371 | if (size > buffer_size) | |
372 | goto cleanup; | |
373 | memcpy(buffer, (void *)IFIRST(header) + | |
374 | le16_to_cpu(entry->e_value_offs), size); | |
375 | } | |
376 | error = size; | |
377 | ||
378 | cleanup: | |
379 | brelse(iloc.bh); | |
380 | return error; | |
381 | } | |
382 | ||
383 | /* | |
617ba13b | 384 | * ext4_xattr_get() |
ac27a0ec DK |
385 | * |
386 | * Copy an extended attribute into the buffer | |
387 | * provided, or compute the buffer size required. | |
388 | * Buffer is NULL to compute the size of the buffer required. | |
389 | * | |
390 | * Returns a negative error number on failure, or the number of bytes | |
391 | * used / required on success. | |
392 | */ | |
393 | int | |
617ba13b | 394 | ext4_xattr_get(struct inode *inode, int name_index, const char *name, |
ac27a0ec DK |
395 | void *buffer, size_t buffer_size) |
396 | { | |
397 | int error; | |
398 | ||
230b8c1a ZZ |
399 | if (strlen(name) > 255) |
400 | return -ERANGE; | |
401 | ||
617ba13b MC |
402 | down_read(&EXT4_I(inode)->xattr_sem); |
403 | error = ext4_xattr_ibody_get(inode, name_index, name, buffer, | |
ac27a0ec DK |
404 | buffer_size); |
405 | if (error == -ENODATA) | |
617ba13b | 406 | error = ext4_xattr_block_get(inode, name_index, name, buffer, |
ac27a0ec | 407 | buffer_size); |
617ba13b | 408 | up_read(&EXT4_I(inode)->xattr_sem); |
ac27a0ec DK |
409 | return error; |
410 | } | |
411 | ||
412 | static int | |
431547b3 | 413 | ext4_xattr_list_entries(struct dentry *dentry, struct ext4_xattr_entry *entry, |
ac27a0ec DK |
414 | char *buffer, size_t buffer_size) |
415 | { | |
416 | size_t rest = buffer_size; | |
417 | ||
617ba13b | 418 | for (; !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) { |
11e27528 | 419 | const struct xattr_handler *handler = |
617ba13b | 420 | ext4_xattr_handler(entry->e_name_index); |
ac27a0ec | 421 | |
764a5c6b AG |
422 | if (handler && (!handler->list || handler->list(dentry))) { |
423 | const char *prefix = handler->prefix ?: handler->name; | |
424 | size_t prefix_len = strlen(prefix); | |
425 | size_t size = prefix_len + entry->e_name_len + 1; | |
426 | ||
ac27a0ec DK |
427 | if (buffer) { |
428 | if (size > rest) | |
429 | return -ERANGE; | |
764a5c6b AG |
430 | memcpy(buffer, prefix, prefix_len); |
431 | buffer += prefix_len; | |
432 | memcpy(buffer, entry->e_name, entry->e_name_len); | |
433 | buffer += entry->e_name_len; | |
434 | *buffer++ = 0; | |
ac27a0ec DK |
435 | } |
436 | rest -= size; | |
437 | } | |
438 | } | |
764a5c6b | 439 | return buffer_size - rest; /* total size */ |
ac27a0ec DK |
440 | } |
441 | ||
442 | static int | |
431547b3 | 443 | ext4_xattr_block_list(struct dentry *dentry, char *buffer, size_t buffer_size) |
ac27a0ec | 444 | { |
2b0143b5 | 445 | struct inode *inode = d_inode(dentry); |
ac27a0ec DK |
446 | struct buffer_head *bh = NULL; |
447 | int error; | |
7a2508e1 | 448 | struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode); |
ac27a0ec DK |
449 | |
450 | ea_idebug(inode, "buffer=%p, buffer_size=%ld", | |
451 | buffer, (long)buffer_size); | |
452 | ||
453 | error = 0; | |
617ba13b | 454 | if (!EXT4_I(inode)->i_file_acl) |
ac27a0ec | 455 | goto cleanup; |
ace36ad4 JP |
456 | ea_idebug(inode, "reading block %llu", |
457 | (unsigned long long)EXT4_I(inode)->i_file_acl); | |
617ba13b | 458 | bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl); |
ac27a0ec DK |
459 | error = -EIO; |
460 | if (!bh) | |
461 | goto cleanup; | |
462 | ea_bdebug(bh, "b_count=%d, refcount=%d", | |
463 | atomic_read(&(bh->b_count)), le32_to_cpu(BHDR(bh)->h_refcount)); | |
cc8e94fd | 464 | if (ext4_xattr_check_block(inode, bh)) { |
24676da4 TT |
465 | EXT4_ERROR_INODE(inode, "bad block %llu", |
466 | EXT4_I(inode)->i_file_acl); | |
6a797d27 | 467 | error = -EFSCORRUPTED; |
ac27a0ec DK |
468 | goto cleanup; |
469 | } | |
9c191f70 | 470 | ext4_xattr_cache_insert(ext4_mb_cache, bh); |
431547b3 | 471 | error = ext4_xattr_list_entries(dentry, BFIRST(bh), buffer, buffer_size); |
ac27a0ec DK |
472 | |
473 | cleanup: | |
474 | brelse(bh); | |
475 | ||
476 | return error; | |
477 | } | |
478 | ||
479 | static int | |
431547b3 | 480 | ext4_xattr_ibody_list(struct dentry *dentry, char *buffer, size_t buffer_size) |
ac27a0ec | 481 | { |
2b0143b5 | 482 | struct inode *inode = d_inode(dentry); |
617ba13b MC |
483 | struct ext4_xattr_ibody_header *header; |
484 | struct ext4_inode *raw_inode; | |
485 | struct ext4_iloc iloc; | |
ac27a0ec DK |
486 | void *end; |
487 | int error; | |
488 | ||
19f5fb7a | 489 | if (!ext4_test_inode_state(inode, EXT4_STATE_XATTR)) |
ac27a0ec | 490 | return 0; |
617ba13b | 491 | error = ext4_get_inode_loc(inode, &iloc); |
ac27a0ec DK |
492 | if (error) |
493 | return error; | |
617ba13b | 494 | raw_inode = ext4_raw_inode(&iloc); |
ac27a0ec | 495 | header = IHDR(inode, raw_inode); |
617ba13b | 496 | end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; |
9e92f48c | 497 | error = xattr_check_inode(inode, header, end); |
ac27a0ec DK |
498 | if (error) |
499 | goto cleanup; | |
431547b3 | 500 | error = ext4_xattr_list_entries(dentry, IFIRST(header), |
ac27a0ec DK |
501 | buffer, buffer_size); |
502 | ||
503 | cleanup: | |
504 | brelse(iloc.bh); | |
505 | return error; | |
506 | } | |
507 | ||
508 | /* | |
617ba13b | 509 | * ext4_xattr_list() |
ac27a0ec DK |
510 | * |
511 | * Copy a list of attribute names into the buffer | |
512 | * provided, or compute the buffer size required. | |
513 | * Buffer is NULL to compute the size of the buffer required. | |
514 | * | |
515 | * Returns a negative error number on failure, or the number of bytes | |
516 | * used / required on success. | |
517 | */ | |
d3a95d47 | 518 | static int |
431547b3 | 519 | ext4_xattr_list(struct dentry *dentry, char *buffer, size_t buffer_size) |
ac27a0ec | 520 | { |
eaeef867 | 521 | int ret, ret2; |
ac27a0ec | 522 | |
2b0143b5 | 523 | down_read(&EXT4_I(d_inode(dentry))->xattr_sem); |
eaeef867 TT |
524 | ret = ret2 = ext4_xattr_ibody_list(dentry, buffer, buffer_size); |
525 | if (ret < 0) | |
526 | goto errout; | |
527 | if (buffer) { | |
528 | buffer += ret; | |
529 | buffer_size -= ret; | |
ac27a0ec | 530 | } |
eaeef867 TT |
531 | ret = ext4_xattr_block_list(dentry, buffer, buffer_size); |
532 | if (ret < 0) | |
533 | goto errout; | |
534 | ret += ret2; | |
535 | errout: | |
2b0143b5 | 536 | up_read(&EXT4_I(d_inode(dentry))->xattr_sem); |
eaeef867 | 537 | return ret; |
ac27a0ec DK |
538 | } |
539 | ||
540 | /* | |
617ba13b | 541 | * If the EXT4_FEATURE_COMPAT_EXT_ATTR feature of this file system is |
ac27a0ec DK |
542 | * not set, set it. |
543 | */ | |
617ba13b | 544 | static void ext4_xattr_update_super_block(handle_t *handle, |
ac27a0ec DK |
545 | struct super_block *sb) |
546 | { | |
e2b911c5 | 547 | if (ext4_has_feature_xattr(sb)) |
ac27a0ec DK |
548 | return; |
549 | ||
5d601255 | 550 | BUFFER_TRACE(EXT4_SB(sb)->s_sbh, "get_write_access"); |
617ba13b | 551 | if (ext4_journal_get_write_access(handle, EXT4_SB(sb)->s_sbh) == 0) { |
e2b911c5 | 552 | ext4_set_feature_xattr(sb); |
a0375156 | 553 | ext4_handle_dirty_super(handle, sb); |
ac27a0ec | 554 | } |
ac27a0ec DK |
555 | } |
556 | ||
557 | /* | |
ec4cb1aa JK |
558 | * Release the xattr block BH: If the reference count is > 1, decrement it; |
559 | * otherwise free the block. | |
ac27a0ec DK |
560 | */ |
561 | static void | |
617ba13b | 562 | ext4_xattr_release_block(handle_t *handle, struct inode *inode, |
ac27a0ec DK |
563 | struct buffer_head *bh) |
564 | { | |
6048c64b AG |
565 | struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode); |
566 | u32 hash, ref; | |
8a2bfdcb | 567 | int error = 0; |
ac27a0ec | 568 | |
5d601255 | 569 | BUFFER_TRACE(bh, "get_write_access"); |
8a2bfdcb MC |
570 | error = ext4_journal_get_write_access(handle, bh); |
571 | if (error) | |
572 | goto out; | |
573 | ||
574 | lock_buffer(bh); | |
6048c64b AG |
575 | hash = le32_to_cpu(BHDR(bh)->h_hash); |
576 | ref = le32_to_cpu(BHDR(bh)->h_refcount); | |
577 | if (ref == 1) { | |
ac27a0ec | 578 | ea_bdebug(bh, "refcount now=0; freeing"); |
82939d79 JK |
579 | /* |
580 | * This must happen under buffer lock for | |
581 | * ext4_xattr_block_set() to reliably detect freed block | |
582 | */ | |
6048c64b | 583 | mb_cache_entry_delete_block(ext4_mb_cache, hash, bh->b_blocknr); |
ac27a0ec | 584 | get_bh(bh); |
ec4cb1aa | 585 | unlock_buffer(bh); |
e6362609 TT |
586 | ext4_free_blocks(handle, inode, bh, 0, 1, |
587 | EXT4_FREE_BLOCKS_METADATA | | |
588 | EXT4_FREE_BLOCKS_FORGET); | |
ac27a0ec | 589 | } else { |
6048c64b AG |
590 | ref--; |
591 | BHDR(bh)->h_refcount = cpu_to_le32(ref); | |
592 | if (ref == EXT4_XATTR_REFCOUNT_MAX - 1) { | |
593 | struct mb_cache_entry *ce; | |
594 | ||
595 | ce = mb_cache_entry_get(ext4_mb_cache, hash, | |
596 | bh->b_blocknr); | |
597 | if (ce) { | |
598 | ce->e_reusable = 1; | |
599 | mb_cache_entry_put(ext4_mb_cache, ce); | |
600 | } | |
601 | } | |
602 | ||
ec4cb1aa JK |
603 | /* |
604 | * Beware of this ugliness: Releasing of xattr block references | |
605 | * from different inodes can race and so we have to protect | |
606 | * from a race where someone else frees the block (and releases | |
607 | * its journal_head) before we are done dirtying the buffer. In | |
608 | * nojournal mode this race is harmless and we actually cannot | |
609 | * call ext4_handle_dirty_xattr_block() with locked buffer as | |
610 | * that function can call sync_dirty_buffer() so for that case | |
611 | * we handle the dirtying after unlocking the buffer. | |
612 | */ | |
613 | if (ext4_handle_valid(handle)) | |
614 | error = ext4_handle_dirty_xattr_block(handle, inode, | |
615 | bh); | |
c1bb05a6 | 616 | unlock_buffer(bh); |
ec4cb1aa JK |
617 | if (!ext4_handle_valid(handle)) |
618 | error = ext4_handle_dirty_xattr_block(handle, inode, | |
619 | bh); | |
8a2bfdcb | 620 | if (IS_SYNC(inode)) |
0390131b | 621 | ext4_handle_sync(handle); |
1231b3a1 | 622 | dquot_free_block(inode, EXT4_C2B(EXT4_SB(inode->i_sb), 1)); |
8a2bfdcb MC |
623 | ea_bdebug(bh, "refcount now=%d; releasing", |
624 | le32_to_cpu(BHDR(bh)->h_refcount)); | |
ac27a0ec | 625 | } |
8a2bfdcb MC |
626 | out: |
627 | ext4_std_error(inode->i_sb, error); | |
628 | return; | |
ac27a0ec DK |
629 | } |
630 | ||
6dd4ee7c KS |
631 | /* |
632 | * Find the available free space for EAs. This also returns the total number of | |
633 | * bytes used by EA entries. | |
634 | */ | |
635 | static size_t ext4_xattr_free_space(struct ext4_xattr_entry *last, | |
636 | size_t *min_offs, void *base, int *total) | |
637 | { | |
638 | for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) { | |
1cba4237 | 639 | if (last->e_value_size) { |
6dd4ee7c KS |
640 | size_t offs = le16_to_cpu(last->e_value_offs); |
641 | if (offs < *min_offs) | |
642 | *min_offs = offs; | |
643 | } | |
7b1b2c1b TT |
644 | if (total) |
645 | *total += EXT4_XATTR_LEN(last->e_name_len); | |
6dd4ee7c KS |
646 | } |
647 | return (*min_offs - ((void *)last - base) - sizeof(__u32)); | |
648 | } | |
649 | ||
ac27a0ec | 650 | static int |
617ba13b | 651 | ext4_xattr_set_entry(struct ext4_xattr_info *i, struct ext4_xattr_search *s) |
ac27a0ec | 652 | { |
617ba13b | 653 | struct ext4_xattr_entry *last; |
ac27a0ec DK |
654 | size_t free, min_offs = s->end - s->base, name_len = strlen(i->name); |
655 | ||
656 | /* Compute min_offs and last. */ | |
657 | last = s->first; | |
617ba13b | 658 | for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) { |
1cba4237 | 659 | if (last->e_value_size) { |
ac27a0ec DK |
660 | size_t offs = le16_to_cpu(last->e_value_offs); |
661 | if (offs < min_offs) | |
662 | min_offs = offs; | |
663 | } | |
664 | } | |
665 | free = min_offs - ((void *)last - s->base) - sizeof(__u32); | |
666 | if (!s->not_found) { | |
1cba4237 | 667 | if (s->here->e_value_size) { |
ac27a0ec | 668 | size_t size = le32_to_cpu(s->here->e_value_size); |
617ba13b | 669 | free += EXT4_XATTR_SIZE(size); |
ac27a0ec | 670 | } |
617ba13b | 671 | free += EXT4_XATTR_LEN(name_len); |
ac27a0ec DK |
672 | } |
673 | if (i->value) { | |
5f80f62a | 674 | if (free < EXT4_XATTR_LEN(name_len) + |
617ba13b | 675 | EXT4_XATTR_SIZE(i->value_len)) |
ac27a0ec DK |
676 | return -ENOSPC; |
677 | } | |
678 | ||
679 | if (i->value && s->not_found) { | |
680 | /* Insert the new name. */ | |
617ba13b | 681 | size_t size = EXT4_XATTR_LEN(name_len); |
ac27a0ec DK |
682 | size_t rest = (void *)last - (void *)s->here + sizeof(__u32); |
683 | memmove((void *)s->here + size, s->here, rest); | |
684 | memset(s->here, 0, size); | |
685 | s->here->e_name_index = i->name_index; | |
686 | s->here->e_name_len = name_len; | |
687 | memcpy(s->here->e_name, i->name, name_len); | |
688 | } else { | |
1cba4237 | 689 | if (s->here->e_value_size) { |
ac27a0ec DK |
690 | void *first_val = s->base + min_offs; |
691 | size_t offs = le16_to_cpu(s->here->e_value_offs); | |
692 | void *val = s->base + offs; | |
617ba13b | 693 | size_t size = EXT4_XATTR_SIZE( |
ac27a0ec DK |
694 | le32_to_cpu(s->here->e_value_size)); |
695 | ||
617ba13b | 696 | if (i->value && size == EXT4_XATTR_SIZE(i->value_len)) { |
ac27a0ec DK |
697 | /* The old and the new value have the same |
698 | size. Just replace. */ | |
699 | s->here->e_value_size = | |
700 | cpu_to_le32(i->value_len); | |
bd9926e8 TT |
701 | if (i->value == EXT4_ZERO_XATTR_VALUE) { |
702 | memset(val, 0, size); | |
703 | } else { | |
704 | /* Clear pad bytes first. */ | |
705 | memset(val + size - EXT4_XATTR_PAD, 0, | |
706 | EXT4_XATTR_PAD); | |
707 | memcpy(val, i->value, i->value_len); | |
708 | } | |
ac27a0ec DK |
709 | return 0; |
710 | } | |
711 | ||
712 | /* Remove the old value. */ | |
713 | memmove(first_val + size, first_val, val - first_val); | |
714 | memset(first_val, 0, size); | |
715 | s->here->e_value_size = 0; | |
716 | s->here->e_value_offs = 0; | |
717 | min_offs += size; | |
718 | ||
719 | /* Adjust all value offsets. */ | |
720 | last = s->first; | |
721 | while (!IS_LAST_ENTRY(last)) { | |
722 | size_t o = le16_to_cpu(last->e_value_offs); | |
1cba4237 | 723 | if (last->e_value_size && o < offs) |
ac27a0ec DK |
724 | last->e_value_offs = |
725 | cpu_to_le16(o + size); | |
617ba13b | 726 | last = EXT4_XATTR_NEXT(last); |
ac27a0ec DK |
727 | } |
728 | } | |
729 | if (!i->value) { | |
730 | /* Remove the old name. */ | |
617ba13b | 731 | size_t size = EXT4_XATTR_LEN(name_len); |
ac27a0ec DK |
732 | last = ENTRY((void *)last - size); |
733 | memmove(s->here, (void *)s->here + size, | |
734 | (void *)last - (void *)s->here + sizeof(__u32)); | |
735 | memset(last, 0, size); | |
736 | } | |
737 | } | |
738 | ||
739 | if (i->value) { | |
740 | /* Insert the new value. */ | |
741 | s->here->e_value_size = cpu_to_le32(i->value_len); | |
742 | if (i->value_len) { | |
617ba13b | 743 | size_t size = EXT4_XATTR_SIZE(i->value_len); |
ac27a0ec DK |
744 | void *val = s->base + min_offs - size; |
745 | s->here->e_value_offs = cpu_to_le16(min_offs - size); | |
bd9926e8 TT |
746 | if (i->value == EXT4_ZERO_XATTR_VALUE) { |
747 | memset(val, 0, size); | |
748 | } else { | |
749 | /* Clear the pad bytes first. */ | |
750 | memset(val + size - EXT4_XATTR_PAD, 0, | |
751 | EXT4_XATTR_PAD); | |
752 | memcpy(val, i->value, i->value_len); | |
753 | } | |
ac27a0ec DK |
754 | } |
755 | } | |
756 | return 0; | |
757 | } | |
758 | ||
617ba13b MC |
759 | struct ext4_xattr_block_find { |
760 | struct ext4_xattr_search s; | |
ac27a0ec DK |
761 | struct buffer_head *bh; |
762 | }; | |
763 | ||
764 | static int | |
617ba13b MC |
765 | ext4_xattr_block_find(struct inode *inode, struct ext4_xattr_info *i, |
766 | struct ext4_xattr_block_find *bs) | |
ac27a0ec DK |
767 | { |
768 | struct super_block *sb = inode->i_sb; | |
769 | int error; | |
770 | ||
771 | ea_idebug(inode, "name=%d.%s, value=%p, value_len=%ld", | |
772 | i->name_index, i->name, i->value, (long)i->value_len); | |
773 | ||
617ba13b | 774 | if (EXT4_I(inode)->i_file_acl) { |
ac27a0ec | 775 | /* The inode already has an extended attribute block. */ |
617ba13b | 776 | bs->bh = sb_bread(sb, EXT4_I(inode)->i_file_acl); |
ac27a0ec DK |
777 | error = -EIO; |
778 | if (!bs->bh) | |
779 | goto cleanup; | |
780 | ea_bdebug(bs->bh, "b_count=%d, refcount=%d", | |
781 | atomic_read(&(bs->bh->b_count)), | |
782 | le32_to_cpu(BHDR(bs->bh)->h_refcount)); | |
cc8e94fd | 783 | if (ext4_xattr_check_block(inode, bs->bh)) { |
24676da4 TT |
784 | EXT4_ERROR_INODE(inode, "bad block %llu", |
785 | EXT4_I(inode)->i_file_acl); | |
6a797d27 | 786 | error = -EFSCORRUPTED; |
ac27a0ec DK |
787 | goto cleanup; |
788 | } | |
789 | /* Find the named attribute. */ | |
790 | bs->s.base = BHDR(bs->bh); | |
791 | bs->s.first = BFIRST(bs->bh); | |
792 | bs->s.end = bs->bh->b_data + bs->bh->b_size; | |
793 | bs->s.here = bs->s.first; | |
617ba13b | 794 | error = ext4_xattr_find_entry(&bs->s.here, i->name_index, |
ac27a0ec DK |
795 | i->name, bs->bh->b_size, 1); |
796 | if (error && error != -ENODATA) | |
797 | goto cleanup; | |
798 | bs->s.not_found = error; | |
799 | } | |
800 | error = 0; | |
801 | ||
802 | cleanup: | |
803 | return error; | |
804 | } | |
805 | ||
806 | static int | |
617ba13b MC |
807 | ext4_xattr_block_set(handle_t *handle, struct inode *inode, |
808 | struct ext4_xattr_info *i, | |
809 | struct ext4_xattr_block_find *bs) | |
ac27a0ec DK |
810 | { |
811 | struct super_block *sb = inode->i_sb; | |
812 | struct buffer_head *new_bh = NULL; | |
617ba13b | 813 | struct ext4_xattr_search *s = &bs->s; |
7a2508e1 | 814 | struct mb_cache_entry *ce = NULL; |
8a2bfdcb | 815 | int error = 0; |
7a2508e1 | 816 | struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode); |
ac27a0ec | 817 | |
617ba13b | 818 | #define header(x) ((struct ext4_xattr_header *)(x)) |
ac27a0ec DK |
819 | |
820 | if (i->value && i->value_len > sb->s_blocksize) | |
821 | return -ENOSPC; | |
822 | if (s->base) { | |
5d601255 | 823 | BUFFER_TRACE(bs->bh, "get_write_access"); |
8a2bfdcb MC |
824 | error = ext4_journal_get_write_access(handle, bs->bh); |
825 | if (error) | |
826 | goto cleanup; | |
827 | lock_buffer(bs->bh); | |
828 | ||
ac27a0ec | 829 | if (header(s->base)->h_refcount == cpu_to_le32(1)) { |
82939d79 JK |
830 | __u32 hash = le32_to_cpu(BHDR(bs->bh)->h_hash); |
831 | ||
832 | /* | |
833 | * This must happen under buffer lock for | |
834 | * ext4_xattr_block_set() to reliably detect modified | |
835 | * block | |
836 | */ | |
7a2508e1 JK |
837 | mb_cache_entry_delete_block(ext4_mb_cache, hash, |
838 | bs->bh->b_blocknr); | |
ac27a0ec | 839 | ea_bdebug(bs->bh, "modifying in-place"); |
617ba13b | 840 | error = ext4_xattr_set_entry(i, s); |
ac27a0ec DK |
841 | if (!error) { |
842 | if (!IS_LAST_ENTRY(s->first)) | |
617ba13b | 843 | ext4_xattr_rehash(header(s->base), |
ac27a0ec | 844 | s->here); |
9c191f70 M |
845 | ext4_xattr_cache_insert(ext4_mb_cache, |
846 | bs->bh); | |
ac27a0ec DK |
847 | } |
848 | unlock_buffer(bs->bh); | |
6a797d27 | 849 | if (error == -EFSCORRUPTED) |
ac27a0ec DK |
850 | goto bad_block; |
851 | if (!error) | |
cc8e94fd DW |
852 | error = ext4_handle_dirty_xattr_block(handle, |
853 | inode, | |
854 | bs->bh); | |
ac27a0ec DK |
855 | if (error) |
856 | goto cleanup; | |
857 | goto inserted; | |
858 | } else { | |
859 | int offset = (char *)s->here - bs->bh->b_data; | |
860 | ||
8a2bfdcb | 861 | unlock_buffer(bs->bh); |
ac27a0ec | 862 | ea_bdebug(bs->bh, "cloning"); |
216553c4 | 863 | s->base = kmalloc(bs->bh->b_size, GFP_NOFS); |
ac27a0ec DK |
864 | error = -ENOMEM; |
865 | if (s->base == NULL) | |
866 | goto cleanup; | |
867 | memcpy(s->base, BHDR(bs->bh), bs->bh->b_size); | |
868 | s->first = ENTRY(header(s->base)+1); | |
869 | header(s->base)->h_refcount = cpu_to_le32(1); | |
870 | s->here = ENTRY(s->base + offset); | |
871 | s->end = s->base + bs->bh->b_size; | |
872 | } | |
873 | } else { | |
874 | /* Allocate a buffer where we construct the new block. */ | |
216553c4 | 875 | s->base = kzalloc(sb->s_blocksize, GFP_NOFS); |
ac27a0ec DK |
876 | /* assert(header == s->base) */ |
877 | error = -ENOMEM; | |
878 | if (s->base == NULL) | |
879 | goto cleanup; | |
617ba13b | 880 | header(s->base)->h_magic = cpu_to_le32(EXT4_XATTR_MAGIC); |
ac27a0ec DK |
881 | header(s->base)->h_blocks = cpu_to_le32(1); |
882 | header(s->base)->h_refcount = cpu_to_le32(1); | |
883 | s->first = ENTRY(header(s->base)+1); | |
884 | s->here = ENTRY(header(s->base)+1); | |
885 | s->end = s->base + sb->s_blocksize; | |
886 | } | |
887 | ||
617ba13b | 888 | error = ext4_xattr_set_entry(i, s); |
6a797d27 | 889 | if (error == -EFSCORRUPTED) |
ac27a0ec DK |
890 | goto bad_block; |
891 | if (error) | |
892 | goto cleanup; | |
893 | if (!IS_LAST_ENTRY(s->first)) | |
617ba13b | 894 | ext4_xattr_rehash(header(s->base), s->here); |
ac27a0ec DK |
895 | |
896 | inserted: | |
897 | if (!IS_LAST_ENTRY(s->first)) { | |
617ba13b | 898 | new_bh = ext4_xattr_cache_find(inode, header(s->base), &ce); |
ac27a0ec DK |
899 | if (new_bh) { |
900 | /* We found an identical block in the cache. */ | |
901 | if (new_bh == bs->bh) | |
902 | ea_bdebug(new_bh, "keeping"); | |
903 | else { | |
6048c64b AG |
904 | u32 ref; |
905 | ||
ac27a0ec DK |
906 | /* The old block is released after updating |
907 | the inode. */ | |
1231b3a1 LC |
908 | error = dquot_alloc_block(inode, |
909 | EXT4_C2B(EXT4_SB(sb), 1)); | |
5dd4056d | 910 | if (error) |
ac27a0ec | 911 | goto cleanup; |
5d601255 | 912 | BUFFER_TRACE(new_bh, "get_write_access"); |
617ba13b | 913 | error = ext4_journal_get_write_access(handle, |
ac27a0ec DK |
914 | new_bh); |
915 | if (error) | |
916 | goto cleanup_dquot; | |
917 | lock_buffer(new_bh); | |
82939d79 JK |
918 | /* |
919 | * We have to be careful about races with | |
6048c64b AG |
920 | * freeing, rehashing or adding references to |
921 | * xattr block. Once we hold buffer lock xattr | |
922 | * block's state is stable so we can check | |
923 | * whether the block got freed / rehashed or | |
924 | * not. Since we unhash mbcache entry under | |
925 | * buffer lock when freeing / rehashing xattr | |
926 | * block, checking whether entry is still | |
927 | * hashed is reliable. Same rules hold for | |
928 | * e_reusable handling. | |
82939d79 | 929 | */ |
6048c64b AG |
930 | if (hlist_bl_unhashed(&ce->e_hash_list) || |
931 | !ce->e_reusable) { | |
82939d79 JK |
932 | /* |
933 | * Undo everything and check mbcache | |
934 | * again. | |
935 | */ | |
936 | unlock_buffer(new_bh); | |
937 | dquot_free_block(inode, | |
938 | EXT4_C2B(EXT4_SB(sb), | |
939 | 1)); | |
940 | brelse(new_bh); | |
7a2508e1 | 941 | mb_cache_entry_put(ext4_mb_cache, ce); |
82939d79 JK |
942 | ce = NULL; |
943 | new_bh = NULL; | |
944 | goto inserted; | |
945 | } | |
6048c64b AG |
946 | ref = le32_to_cpu(BHDR(new_bh)->h_refcount) + 1; |
947 | BHDR(new_bh)->h_refcount = cpu_to_le32(ref); | |
948 | if (ref >= EXT4_XATTR_REFCOUNT_MAX) | |
949 | ce->e_reusable = 0; | |
ac27a0ec | 950 | ea_bdebug(new_bh, "reusing; refcount now=%d", |
6048c64b | 951 | ref); |
ac27a0ec | 952 | unlock_buffer(new_bh); |
cc8e94fd DW |
953 | error = ext4_handle_dirty_xattr_block(handle, |
954 | inode, | |
955 | new_bh); | |
ac27a0ec DK |
956 | if (error) |
957 | goto cleanup_dquot; | |
958 | } | |
7a2508e1 JK |
959 | mb_cache_entry_touch(ext4_mb_cache, ce); |
960 | mb_cache_entry_put(ext4_mb_cache, ce); | |
ac27a0ec DK |
961 | ce = NULL; |
962 | } else if (bs->bh && s->base == bs->bh->b_data) { | |
963 | /* We were modifying this block in-place. */ | |
964 | ea_bdebug(bs->bh, "keeping this block"); | |
965 | new_bh = bs->bh; | |
966 | get_bh(new_bh); | |
967 | } else { | |
968 | /* We need to allocate a new block */ | |
fb0a387d ES |
969 | ext4_fsblk_t goal, block; |
970 | ||
971 | goal = ext4_group_first_block_no(sb, | |
d00a6d7b | 972 | EXT4_I(inode)->i_block_group); |
fb0a387d ES |
973 | |
974 | /* non-extent files can't have physical blocks past 2^32 */ | |
12e9b892 | 975 | if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) |
fb0a387d ES |
976 | goal = goal & EXT4_MAX_BLOCK_FILE_PHYS; |
977 | ||
55f020db AH |
978 | block = ext4_new_meta_blocks(handle, inode, goal, 0, |
979 | NULL, &error); | |
ac27a0ec DK |
980 | if (error) |
981 | goto cleanup; | |
fb0a387d | 982 | |
12e9b892 | 983 | if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) |
fb0a387d ES |
984 | BUG_ON(block > EXT4_MAX_BLOCK_FILE_PHYS); |
985 | ||
ace36ad4 JP |
986 | ea_idebug(inode, "creating block %llu", |
987 | (unsigned long long)block); | |
ac27a0ec DK |
988 | |
989 | new_bh = sb_getblk(sb, block); | |
aebf0243 | 990 | if (unlikely(!new_bh)) { |
860d21e2 | 991 | error = -ENOMEM; |
ac27a0ec | 992 | getblk_failed: |
7dc57615 | 993 | ext4_free_blocks(handle, inode, NULL, block, 1, |
e6362609 | 994 | EXT4_FREE_BLOCKS_METADATA); |
ac27a0ec DK |
995 | goto cleanup; |
996 | } | |
997 | lock_buffer(new_bh); | |
617ba13b | 998 | error = ext4_journal_get_create_access(handle, new_bh); |
ac27a0ec DK |
999 | if (error) { |
1000 | unlock_buffer(new_bh); | |
860d21e2 | 1001 | error = -EIO; |
ac27a0ec DK |
1002 | goto getblk_failed; |
1003 | } | |
1004 | memcpy(new_bh->b_data, s->base, new_bh->b_size); | |
1005 | set_buffer_uptodate(new_bh); | |
1006 | unlock_buffer(new_bh); | |
9c191f70 | 1007 | ext4_xattr_cache_insert(ext4_mb_cache, new_bh); |
cc8e94fd DW |
1008 | error = ext4_handle_dirty_xattr_block(handle, |
1009 | inode, new_bh); | |
ac27a0ec DK |
1010 | if (error) |
1011 | goto cleanup; | |
1012 | } | |
1013 | } | |
1014 | ||
1015 | /* Update the inode. */ | |
617ba13b | 1016 | EXT4_I(inode)->i_file_acl = new_bh ? new_bh->b_blocknr : 0; |
ac27a0ec DK |
1017 | |
1018 | /* Drop the previous xattr block. */ | |
1019 | if (bs->bh && bs->bh != new_bh) | |
617ba13b | 1020 | ext4_xattr_release_block(handle, inode, bs->bh); |
ac27a0ec DK |
1021 | error = 0; |
1022 | ||
1023 | cleanup: | |
1024 | if (ce) | |
7a2508e1 | 1025 | mb_cache_entry_put(ext4_mb_cache, ce); |
ac27a0ec DK |
1026 | brelse(new_bh); |
1027 | if (!(bs->bh && s->base == bs->bh->b_data)) | |
1028 | kfree(s->base); | |
1029 | ||
1030 | return error; | |
1031 | ||
1032 | cleanup_dquot: | |
1231b3a1 | 1033 | dquot_free_block(inode, EXT4_C2B(EXT4_SB(sb), 1)); |
ac27a0ec DK |
1034 | goto cleanup; |
1035 | ||
1036 | bad_block: | |
24676da4 TT |
1037 | EXT4_ERROR_INODE(inode, "bad block %llu", |
1038 | EXT4_I(inode)->i_file_acl); | |
ac27a0ec DK |
1039 | goto cleanup; |
1040 | ||
1041 | #undef header | |
1042 | } | |
1043 | ||
879b3825 TM |
1044 | int ext4_xattr_ibody_find(struct inode *inode, struct ext4_xattr_info *i, |
1045 | struct ext4_xattr_ibody_find *is) | |
ac27a0ec | 1046 | { |
617ba13b MC |
1047 | struct ext4_xattr_ibody_header *header; |
1048 | struct ext4_inode *raw_inode; | |
ac27a0ec DK |
1049 | int error; |
1050 | ||
617ba13b | 1051 | if (EXT4_I(inode)->i_extra_isize == 0) |
ac27a0ec | 1052 | return 0; |
617ba13b | 1053 | raw_inode = ext4_raw_inode(&is->iloc); |
ac27a0ec DK |
1054 | header = IHDR(inode, raw_inode); |
1055 | is->s.base = is->s.first = IFIRST(header); | |
1056 | is->s.here = is->s.first; | |
617ba13b | 1057 | is->s.end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; |
19f5fb7a | 1058 | if (ext4_test_inode_state(inode, EXT4_STATE_XATTR)) { |
9e92f48c | 1059 | error = xattr_check_inode(inode, header, is->s.end); |
ac27a0ec DK |
1060 | if (error) |
1061 | return error; | |
1062 | /* Find the named attribute. */ | |
617ba13b | 1063 | error = ext4_xattr_find_entry(&is->s.here, i->name_index, |
ac27a0ec DK |
1064 | i->name, is->s.end - |
1065 | (void *)is->s.base, 0); | |
1066 | if (error && error != -ENODATA) | |
1067 | return error; | |
1068 | is->s.not_found = error; | |
1069 | } | |
1070 | return 0; | |
1071 | } | |
1072 | ||
0d812f77 TM |
1073 | int ext4_xattr_ibody_inline_set(handle_t *handle, struct inode *inode, |
1074 | struct ext4_xattr_info *i, | |
1075 | struct ext4_xattr_ibody_find *is) | |
1076 | { | |
1077 | struct ext4_xattr_ibody_header *header; | |
1078 | struct ext4_xattr_search *s = &is->s; | |
1079 | int error; | |
1080 | ||
1081 | if (EXT4_I(inode)->i_extra_isize == 0) | |
1082 | return -ENOSPC; | |
1083 | error = ext4_xattr_set_entry(i, s); | |
1084 | if (error) { | |
1085 | if (error == -ENOSPC && | |
1086 | ext4_has_inline_data(inode)) { | |
1087 | error = ext4_try_to_evict_inline_data(handle, inode, | |
1088 | EXT4_XATTR_LEN(strlen(i->name) + | |
1089 | EXT4_XATTR_SIZE(i->value_len))); | |
1090 | if (error) | |
1091 | return error; | |
1092 | error = ext4_xattr_ibody_find(inode, i, is); | |
1093 | if (error) | |
1094 | return error; | |
1095 | error = ext4_xattr_set_entry(i, s); | |
1096 | } | |
1097 | if (error) | |
1098 | return error; | |
1099 | } | |
1100 | header = IHDR(inode, ext4_raw_inode(&is->iloc)); | |
1101 | if (!IS_LAST_ENTRY(s->first)) { | |
1102 | header->h_magic = cpu_to_le32(EXT4_XATTR_MAGIC); | |
1103 | ext4_set_inode_state(inode, EXT4_STATE_XATTR); | |
1104 | } else { | |
1105 | header->h_magic = cpu_to_le32(0); | |
1106 | ext4_clear_inode_state(inode, EXT4_STATE_XATTR); | |
1107 | } | |
1108 | return 0; | |
1109 | } | |
1110 | ||
d5c8dab6 | 1111 | static int ext4_xattr_ibody_set(struct inode *inode, |
0d812f77 TM |
1112 | struct ext4_xattr_info *i, |
1113 | struct ext4_xattr_ibody_find *is) | |
ac27a0ec | 1114 | { |
617ba13b MC |
1115 | struct ext4_xattr_ibody_header *header; |
1116 | struct ext4_xattr_search *s = &is->s; | |
ac27a0ec DK |
1117 | int error; |
1118 | ||
617ba13b | 1119 | if (EXT4_I(inode)->i_extra_isize == 0) |
ac27a0ec | 1120 | return -ENOSPC; |
617ba13b | 1121 | error = ext4_xattr_set_entry(i, s); |
ac27a0ec DK |
1122 | if (error) |
1123 | return error; | |
617ba13b | 1124 | header = IHDR(inode, ext4_raw_inode(&is->iloc)); |
ac27a0ec | 1125 | if (!IS_LAST_ENTRY(s->first)) { |
617ba13b | 1126 | header->h_magic = cpu_to_le32(EXT4_XATTR_MAGIC); |
19f5fb7a | 1127 | ext4_set_inode_state(inode, EXT4_STATE_XATTR); |
ac27a0ec DK |
1128 | } else { |
1129 | header->h_magic = cpu_to_le32(0); | |
19f5fb7a | 1130 | ext4_clear_inode_state(inode, EXT4_STATE_XATTR); |
ac27a0ec DK |
1131 | } |
1132 | return 0; | |
1133 | } | |
1134 | ||
3fd16462 JK |
1135 | static int ext4_xattr_value_same(struct ext4_xattr_search *s, |
1136 | struct ext4_xattr_info *i) | |
1137 | { | |
1138 | void *value; | |
1139 | ||
1140 | if (le32_to_cpu(s->here->e_value_size) != i->value_len) | |
1141 | return 0; | |
1142 | value = ((void *)s->base) + le16_to_cpu(s->here->e_value_offs); | |
1143 | return !memcmp(value, i->value, i->value_len); | |
1144 | } | |
1145 | ||
ac27a0ec | 1146 | /* |
617ba13b | 1147 | * ext4_xattr_set_handle() |
ac27a0ec | 1148 | * |
6e9510b0 | 1149 | * Create, replace or remove an extended attribute for this inode. Value |
ac27a0ec DK |
1150 | * is NULL to remove an existing extended attribute, and non-NULL to |
1151 | * either replace an existing extended attribute, or create a new extended | |
1152 | * attribute. The flags XATTR_REPLACE and XATTR_CREATE | |
1153 | * specify that an extended attribute must exist and must not exist | |
1154 | * previous to the call, respectively. | |
1155 | * | |
1156 | * Returns 0, or a negative error number on failure. | |
1157 | */ | |
1158 | int | |
617ba13b | 1159 | ext4_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index, |
ac27a0ec DK |
1160 | const char *name, const void *value, size_t value_len, |
1161 | int flags) | |
1162 | { | |
617ba13b | 1163 | struct ext4_xattr_info i = { |
ac27a0ec DK |
1164 | .name_index = name_index, |
1165 | .name = name, | |
1166 | .value = value, | |
1167 | .value_len = value_len, | |
1168 | ||
1169 | }; | |
617ba13b | 1170 | struct ext4_xattr_ibody_find is = { |
ac27a0ec DK |
1171 | .s = { .not_found = -ENODATA, }, |
1172 | }; | |
617ba13b | 1173 | struct ext4_xattr_block_find bs = { |
ac27a0ec DK |
1174 | .s = { .not_found = -ENODATA, }, |
1175 | }; | |
4d20c685 | 1176 | unsigned long no_expand; |
ac27a0ec DK |
1177 | int error; |
1178 | ||
1179 | if (!name) | |
1180 | return -EINVAL; | |
1181 | if (strlen(name) > 255) | |
1182 | return -ERANGE; | |
617ba13b | 1183 | down_write(&EXT4_I(inode)->xattr_sem); |
19f5fb7a TT |
1184 | no_expand = ext4_test_inode_state(inode, EXT4_STATE_NO_EXPAND); |
1185 | ext4_set_inode_state(inode, EXT4_STATE_NO_EXPAND); | |
4d20c685 | 1186 | |
66543617 | 1187 | error = ext4_reserve_inode_write(handle, inode, &is.iloc); |
86ebfd08 ES |
1188 | if (error) |
1189 | goto cleanup; | |
1190 | ||
19f5fb7a | 1191 | if (ext4_test_inode_state(inode, EXT4_STATE_NEW)) { |
617ba13b MC |
1192 | struct ext4_inode *raw_inode = ext4_raw_inode(&is.iloc); |
1193 | memset(raw_inode, 0, EXT4_SB(inode->i_sb)->s_inode_size); | |
19f5fb7a | 1194 | ext4_clear_inode_state(inode, EXT4_STATE_NEW); |
ac27a0ec DK |
1195 | } |
1196 | ||
617ba13b | 1197 | error = ext4_xattr_ibody_find(inode, &i, &is); |
ac27a0ec DK |
1198 | if (error) |
1199 | goto cleanup; | |
1200 | if (is.s.not_found) | |
617ba13b | 1201 | error = ext4_xattr_block_find(inode, &i, &bs); |
ac27a0ec DK |
1202 | if (error) |
1203 | goto cleanup; | |
1204 | if (is.s.not_found && bs.s.not_found) { | |
1205 | error = -ENODATA; | |
1206 | if (flags & XATTR_REPLACE) | |
1207 | goto cleanup; | |
1208 | error = 0; | |
1209 | if (!value) | |
1210 | goto cleanup; | |
1211 | } else { | |
1212 | error = -EEXIST; | |
1213 | if (flags & XATTR_CREATE) | |
1214 | goto cleanup; | |
1215 | } | |
ac27a0ec DK |
1216 | if (!value) { |
1217 | if (!is.s.not_found) | |
d5c8dab6 | 1218 | error = ext4_xattr_ibody_set(inode, &i, &is); |
ac27a0ec | 1219 | else if (!bs.s.not_found) |
617ba13b | 1220 | error = ext4_xattr_block_set(handle, inode, &i, &bs); |
ac27a0ec | 1221 | } else { |
3fd16462 JK |
1222 | error = 0; |
1223 | /* Xattr value did not change? Save us some work and bail out */ | |
1224 | if (!is.s.not_found && ext4_xattr_value_same(&is.s, &i)) | |
1225 | goto cleanup; | |
1226 | if (!bs.s.not_found && ext4_xattr_value_same(&bs.s, &i)) | |
1227 | goto cleanup; | |
1228 | ||
d5c8dab6 | 1229 | error = ext4_xattr_ibody_set(inode, &i, &is); |
ac27a0ec DK |
1230 | if (!error && !bs.s.not_found) { |
1231 | i.value = NULL; | |
617ba13b | 1232 | error = ext4_xattr_block_set(handle, inode, &i, &bs); |
ac27a0ec | 1233 | } else if (error == -ENOSPC) { |
7e01c8e5 TY |
1234 | if (EXT4_I(inode)->i_file_acl && !bs.s.base) { |
1235 | error = ext4_xattr_block_find(inode, &i, &bs); | |
1236 | if (error) | |
1237 | goto cleanup; | |
1238 | } | |
617ba13b | 1239 | error = ext4_xattr_block_set(handle, inode, &i, &bs); |
ac27a0ec DK |
1240 | if (error) |
1241 | goto cleanup; | |
1242 | if (!is.s.not_found) { | |
1243 | i.value = NULL; | |
d5c8dab6 | 1244 | error = ext4_xattr_ibody_set(inode, &i, &is); |
ac27a0ec DK |
1245 | } |
1246 | } | |
1247 | } | |
1248 | if (!error) { | |
617ba13b | 1249 | ext4_xattr_update_super_block(handle, inode->i_sb); |
eeca7ea1 | 1250 | inode->i_ctime = current_time(inode); |
6dd4ee7c | 1251 | if (!value) |
19f5fb7a | 1252 | ext4_clear_inode_state(inode, EXT4_STATE_NO_EXPAND); |
617ba13b | 1253 | error = ext4_mark_iloc_dirty(handle, inode, &is.iloc); |
ac27a0ec | 1254 | /* |
617ba13b | 1255 | * The bh is consumed by ext4_mark_iloc_dirty, even with |
ac27a0ec DK |
1256 | * error != 0. |
1257 | */ | |
1258 | is.iloc.bh = NULL; | |
1259 | if (IS_SYNC(inode)) | |
0390131b | 1260 | ext4_handle_sync(handle); |
ac27a0ec DK |
1261 | } |
1262 | ||
1263 | cleanup: | |
1264 | brelse(is.iloc.bh); | |
1265 | brelse(bs.bh); | |
4d20c685 | 1266 | if (no_expand == 0) |
19f5fb7a | 1267 | ext4_clear_inode_state(inode, EXT4_STATE_NO_EXPAND); |
617ba13b | 1268 | up_write(&EXT4_I(inode)->xattr_sem); |
ac27a0ec DK |
1269 | return error; |
1270 | } | |
1271 | ||
1272 | /* | |
617ba13b | 1273 | * ext4_xattr_set() |
ac27a0ec | 1274 | * |
617ba13b | 1275 | * Like ext4_xattr_set_handle, but start from an inode. This extended |
ac27a0ec DK |
1276 | * attribute modification is a filesystem transaction by itself. |
1277 | * | |
1278 | * Returns 0, or a negative error number on failure. | |
1279 | */ | |
1280 | int | |
617ba13b | 1281 | ext4_xattr_set(struct inode *inode, int name_index, const char *name, |
ac27a0ec DK |
1282 | const void *value, size_t value_len, int flags) |
1283 | { | |
1284 | handle_t *handle; | |
1285 | int error, retries = 0; | |
95eaefbd | 1286 | int credits = ext4_jbd2_credits_xattr(inode); |
ac27a0ec DK |
1287 | |
1288 | retry: | |
9924a92a | 1289 | handle = ext4_journal_start(inode, EXT4_HT_XATTR, credits); |
ac27a0ec DK |
1290 | if (IS_ERR(handle)) { |
1291 | error = PTR_ERR(handle); | |
1292 | } else { | |
1293 | int error2; | |
1294 | ||
617ba13b | 1295 | error = ext4_xattr_set_handle(handle, inode, name_index, name, |
ac27a0ec | 1296 | value, value_len, flags); |
617ba13b | 1297 | error2 = ext4_journal_stop(handle); |
ac27a0ec | 1298 | if (error == -ENOSPC && |
617ba13b | 1299 | ext4_should_retry_alloc(inode->i_sb, &retries)) |
ac27a0ec DK |
1300 | goto retry; |
1301 | if (error == 0) | |
1302 | error = error2; | |
1303 | } | |
1304 | ||
1305 | return error; | |
1306 | } | |
1307 | ||
6dd4ee7c KS |
1308 | /* |
1309 | * Shift the EA entries in the inode to create space for the increased | |
1310 | * i_extra_isize. | |
1311 | */ | |
1312 | static void ext4_xattr_shift_entries(struct ext4_xattr_entry *entry, | |
1313 | int value_offs_shift, void *to, | |
94405713 | 1314 | void *from, size_t n) |
6dd4ee7c KS |
1315 | { |
1316 | struct ext4_xattr_entry *last = entry; | |
1317 | int new_offs; | |
1318 | ||
94405713 JK |
1319 | /* We always shift xattr headers further thus offsets get lower */ |
1320 | BUG_ON(value_offs_shift > 0); | |
1321 | ||
6dd4ee7c KS |
1322 | /* Adjust the value offsets of the entries */ |
1323 | for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) { | |
1cba4237 | 1324 | if (last->e_value_size) { |
6dd4ee7c KS |
1325 | new_offs = le16_to_cpu(last->e_value_offs) + |
1326 | value_offs_shift; | |
6dd4ee7c KS |
1327 | last->e_value_offs = cpu_to_le16(new_offs); |
1328 | } | |
1329 | } | |
1330 | /* Shift the entries by n bytes */ | |
1331 | memmove(to, from, n); | |
1332 | } | |
1333 | ||
3f2571c1 JK |
1334 | /* |
1335 | * Move xattr pointed to by 'entry' from inode into external xattr block | |
1336 | */ | |
1337 | static int ext4_xattr_move_to_block(handle_t *handle, struct inode *inode, | |
1338 | struct ext4_inode *raw_inode, | |
1339 | struct ext4_xattr_entry *entry) | |
1340 | { | |
1341 | struct ext4_xattr_ibody_find *is = NULL; | |
1342 | struct ext4_xattr_block_find *bs = NULL; | |
1343 | char *buffer = NULL, *b_entry_name = NULL; | |
1344 | size_t value_offs, value_size; | |
1345 | struct ext4_xattr_info i = { | |
1346 | .value = NULL, | |
1347 | .value_len = 0, | |
1348 | .name_index = entry->e_name_index, | |
1349 | }; | |
1350 | struct ext4_xattr_ibody_header *header = IHDR(inode, raw_inode); | |
1351 | int error; | |
1352 | ||
1353 | value_offs = le16_to_cpu(entry->e_value_offs); | |
1354 | value_size = le32_to_cpu(entry->e_value_size); | |
1355 | ||
1356 | is = kzalloc(sizeof(struct ext4_xattr_ibody_find), GFP_NOFS); | |
1357 | bs = kzalloc(sizeof(struct ext4_xattr_block_find), GFP_NOFS); | |
1358 | buffer = kmalloc(value_size, GFP_NOFS); | |
1359 | b_entry_name = kmalloc(entry->e_name_len + 1, GFP_NOFS); | |
1360 | if (!is || !bs || !buffer || !b_entry_name) { | |
1361 | error = -ENOMEM; | |
1362 | goto out; | |
1363 | } | |
1364 | ||
1365 | is->s.not_found = -ENODATA; | |
1366 | bs->s.not_found = -ENODATA; | |
1367 | is->iloc.bh = NULL; | |
1368 | bs->bh = NULL; | |
1369 | ||
1370 | /* Save the entry name and the entry value */ | |
1371 | memcpy(buffer, (void *)IFIRST(header) + value_offs, value_size); | |
1372 | memcpy(b_entry_name, entry->e_name, entry->e_name_len); | |
1373 | b_entry_name[entry->e_name_len] = '\0'; | |
1374 | i.name = b_entry_name; | |
1375 | ||
1376 | error = ext4_get_inode_loc(inode, &is->iloc); | |
1377 | if (error) | |
1378 | goto out; | |
1379 | ||
1380 | error = ext4_xattr_ibody_find(inode, &i, is); | |
1381 | if (error) | |
1382 | goto out; | |
1383 | ||
1384 | /* Remove the chosen entry from the inode */ | |
d5c8dab6 | 1385 | error = ext4_xattr_ibody_set(inode, &i, is); |
3f2571c1 JK |
1386 | if (error) |
1387 | goto out; | |
1388 | ||
1389 | i.name = b_entry_name; | |
1390 | i.value = buffer; | |
1391 | i.value_len = value_size; | |
1392 | error = ext4_xattr_block_find(inode, &i, bs); | |
1393 | if (error) | |
1394 | goto out; | |
1395 | ||
1396 | /* Add entry which was removed from the inode into the block */ | |
1397 | error = ext4_xattr_block_set(handle, inode, &i, bs); | |
1398 | if (error) | |
1399 | goto out; | |
1400 | error = 0; | |
1401 | out: | |
1402 | kfree(b_entry_name); | |
1403 | kfree(buffer); | |
1404 | if (is) | |
1405 | brelse(is->iloc.bh); | |
1406 | kfree(is); | |
1407 | kfree(bs); | |
1408 | ||
1409 | return error; | |
1410 | } | |
1411 | ||
dfa2064b JK |
1412 | static int ext4_xattr_make_inode_space(handle_t *handle, struct inode *inode, |
1413 | struct ext4_inode *raw_inode, | |
1414 | int isize_diff, size_t ifree, | |
1415 | size_t bfree, int *total_ino) | |
1416 | { | |
1417 | struct ext4_xattr_ibody_header *header = IHDR(inode, raw_inode); | |
1418 | struct ext4_xattr_entry *small_entry; | |
1419 | struct ext4_xattr_entry *entry; | |
1420 | struct ext4_xattr_entry *last; | |
1421 | unsigned int entry_size; /* EA entry size */ | |
1422 | unsigned int total_size; /* EA entry size + value size */ | |
1423 | unsigned int min_total_size; | |
1424 | int error; | |
1425 | ||
1426 | while (isize_diff > ifree) { | |
1427 | entry = NULL; | |
1428 | small_entry = NULL; | |
1429 | min_total_size = ~0U; | |
1430 | last = IFIRST(header); | |
1431 | /* Find the entry best suited to be pushed into EA block */ | |
1432 | for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) { | |
1433 | total_size = | |
1434 | EXT4_XATTR_SIZE(le32_to_cpu(last->e_value_size)) + | |
1435 | EXT4_XATTR_LEN(last->e_name_len); | |
1436 | if (total_size <= bfree && | |
1437 | total_size < min_total_size) { | |
1438 | if (total_size + ifree < isize_diff) { | |
1439 | small_entry = last; | |
1440 | } else { | |
1441 | entry = last; | |
1442 | min_total_size = total_size; | |
1443 | } | |
1444 | } | |
1445 | } | |
1446 | ||
1447 | if (entry == NULL) { | |
1448 | if (small_entry == NULL) | |
1449 | return -ENOSPC; | |
1450 | entry = small_entry; | |
1451 | } | |
1452 | ||
1453 | entry_size = EXT4_XATTR_LEN(entry->e_name_len); | |
1454 | total_size = entry_size + | |
1455 | EXT4_XATTR_SIZE(le32_to_cpu(entry->e_value_size)); | |
1456 | error = ext4_xattr_move_to_block(handle, inode, raw_inode, | |
1457 | entry); | |
1458 | if (error) | |
1459 | return error; | |
1460 | ||
1461 | *total_ino -= entry_size; | |
1462 | ifree += total_size; | |
1463 | bfree -= total_size; | |
1464 | } | |
1465 | ||
1466 | return 0; | |
1467 | } | |
1468 | ||
6dd4ee7c KS |
1469 | /* |
1470 | * Expand an inode by new_extra_isize bytes when EAs are present. | |
1471 | * Returns 0 on success or negative error number on failure. | |
1472 | */ | |
1473 | int ext4_expand_extra_isize_ea(struct inode *inode, int new_extra_isize, | |
1474 | struct ext4_inode *raw_inode, handle_t *handle) | |
1475 | { | |
1476 | struct ext4_xattr_ibody_header *header; | |
6dd4ee7c | 1477 | struct buffer_head *bh = NULL; |
e3014d14 JK |
1478 | size_t min_offs; |
1479 | size_t ifree, bfree; | |
7b1b2c1b | 1480 | int total_ino; |
6e0cd088 | 1481 | void *base, *end; |
d0141191 | 1482 | int error = 0, tried_min_extra_isize = 0; |
ac39849d | 1483 | int s_min_extra_isize = le16_to_cpu(EXT4_SB(inode->i_sb)->s_es->s_min_extra_isize); |
d0141191 | 1484 | int isize_diff; /* How much do we need to grow i_extra_isize */ |
6dd4ee7c KS |
1485 | |
1486 | down_write(&EXT4_I(inode)->xattr_sem); | |
2e81a4ee JK |
1487 | /* |
1488 | * Set EXT4_STATE_NO_EXPAND to avoid recursion when marking inode dirty | |
1489 | */ | |
1490 | ext4_set_inode_state(inode, EXT4_STATE_NO_EXPAND); | |
6dd4ee7c | 1491 | retry: |
d0141191 | 1492 | isize_diff = new_extra_isize - EXT4_I(inode)->i_extra_isize; |
2e81a4ee JK |
1493 | if (EXT4_I(inode)->i_extra_isize >= new_extra_isize) |
1494 | goto out; | |
6dd4ee7c KS |
1495 | |
1496 | header = IHDR(inode, raw_inode); | |
6dd4ee7c KS |
1497 | |
1498 | /* | |
1499 | * Check if enough free space is available in the inode to shift the | |
1500 | * entries ahead by new_extra_isize. | |
1501 | */ | |
1502 | ||
6e0cd088 | 1503 | base = IFIRST(header); |
6dd4ee7c KS |
1504 | end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; |
1505 | min_offs = end - base; | |
6dd4ee7c KS |
1506 | total_ino = sizeof(struct ext4_xattr_ibody_header); |
1507 | ||
9e92f48c TT |
1508 | error = xattr_check_inode(inode, header, end); |
1509 | if (error) | |
1510 | goto cleanup; | |
1511 | ||
6e0cd088 | 1512 | ifree = ext4_xattr_free_space(base, &min_offs, base, &total_ino); |
e3014d14 JK |
1513 | if (ifree >= isize_diff) |
1514 | goto shift; | |
6dd4ee7c KS |
1515 | |
1516 | /* | |
1517 | * Enough free space isn't available in the inode, check if | |
1518 | * EA block can hold new_extra_isize bytes. | |
1519 | */ | |
1520 | if (EXT4_I(inode)->i_file_acl) { | |
1521 | bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl); | |
1522 | error = -EIO; | |
1523 | if (!bh) | |
1524 | goto cleanup; | |
cc8e94fd | 1525 | if (ext4_xattr_check_block(inode, bh)) { |
24676da4 TT |
1526 | EXT4_ERROR_INODE(inode, "bad block %llu", |
1527 | EXT4_I(inode)->i_file_acl); | |
6a797d27 | 1528 | error = -EFSCORRUPTED; |
6dd4ee7c KS |
1529 | goto cleanup; |
1530 | } | |
1531 | base = BHDR(bh); | |
6dd4ee7c KS |
1532 | end = bh->b_data + bh->b_size; |
1533 | min_offs = end - base; | |
6e0cd088 JK |
1534 | bfree = ext4_xattr_free_space(BFIRST(bh), &min_offs, base, |
1535 | NULL); | |
e3014d14 | 1536 | if (bfree + ifree < isize_diff) { |
6dd4ee7c KS |
1537 | if (!tried_min_extra_isize && s_min_extra_isize) { |
1538 | tried_min_extra_isize++; | |
1539 | new_extra_isize = s_min_extra_isize; | |
1540 | brelse(bh); | |
1541 | goto retry; | |
1542 | } | |
dfa2064b | 1543 | error = -ENOSPC; |
6dd4ee7c KS |
1544 | goto cleanup; |
1545 | } | |
1546 | } else { | |
e3014d14 | 1547 | bfree = inode->i_sb->s_blocksize; |
6dd4ee7c KS |
1548 | } |
1549 | ||
dfa2064b JK |
1550 | error = ext4_xattr_make_inode_space(handle, inode, raw_inode, |
1551 | isize_diff, ifree, bfree, | |
1552 | &total_ino); | |
1553 | if (error) { | |
1554 | if (error == -ENOSPC && !tried_min_extra_isize && | |
1555 | s_min_extra_isize) { | |
1556 | tried_min_extra_isize++; | |
1557 | new_extra_isize = s_min_extra_isize; | |
1558 | brelse(bh); | |
1559 | goto retry; | |
6dd4ee7c | 1560 | } |
dfa2064b | 1561 | goto cleanup; |
6dd4ee7c | 1562 | } |
e3014d14 JK |
1563 | shift: |
1564 | /* Adjust the offsets and shift the remaining entries ahead */ | |
6e0cd088 | 1565 | ext4_xattr_shift_entries(IFIRST(header), EXT4_I(inode)->i_extra_isize |
e3014d14 JK |
1566 | - new_extra_isize, (void *)raw_inode + |
1567 | EXT4_GOOD_OLD_INODE_SIZE + new_extra_isize, | |
94405713 | 1568 | (void *)header, total_ino); |
e3014d14 | 1569 | EXT4_I(inode)->i_extra_isize = new_extra_isize; |
6dd4ee7c | 1570 | brelse(bh); |
2e81a4ee JK |
1571 | out: |
1572 | ext4_clear_inode_state(inode, EXT4_STATE_NO_EXPAND); | |
6dd4ee7c KS |
1573 | up_write(&EXT4_I(inode)->xattr_sem); |
1574 | return 0; | |
1575 | ||
1576 | cleanup: | |
6dd4ee7c | 1577 | brelse(bh); |
2e81a4ee JK |
1578 | /* |
1579 | * We deliberately leave EXT4_STATE_NO_EXPAND set here since inode | |
1580 | * size expansion failed. | |
1581 | */ | |
6dd4ee7c KS |
1582 | up_write(&EXT4_I(inode)->xattr_sem); |
1583 | return error; | |
1584 | } | |
1585 | ||
1586 | ||
1587 | ||
ac27a0ec | 1588 | /* |
617ba13b | 1589 | * ext4_xattr_delete_inode() |
ac27a0ec DK |
1590 | * |
1591 | * Free extended attribute resources associated with this inode. This | |
1592 | * is called immediately before an inode is freed. We have exclusive | |
1593 | * access to the inode. | |
1594 | */ | |
1595 | void | |
617ba13b | 1596 | ext4_xattr_delete_inode(handle_t *handle, struct inode *inode) |
ac27a0ec DK |
1597 | { |
1598 | struct buffer_head *bh = NULL; | |
1599 | ||
617ba13b | 1600 | if (!EXT4_I(inode)->i_file_acl) |
ac27a0ec | 1601 | goto cleanup; |
617ba13b | 1602 | bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl); |
ac27a0ec | 1603 | if (!bh) { |
24676da4 TT |
1604 | EXT4_ERROR_INODE(inode, "block %llu read error", |
1605 | EXT4_I(inode)->i_file_acl); | |
ac27a0ec DK |
1606 | goto cleanup; |
1607 | } | |
617ba13b | 1608 | if (BHDR(bh)->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC) || |
ac27a0ec | 1609 | BHDR(bh)->h_blocks != cpu_to_le32(1)) { |
24676da4 TT |
1610 | EXT4_ERROR_INODE(inode, "bad block %llu", |
1611 | EXT4_I(inode)->i_file_acl); | |
ac27a0ec DK |
1612 | goto cleanup; |
1613 | } | |
617ba13b MC |
1614 | ext4_xattr_release_block(handle, inode, bh); |
1615 | EXT4_I(inode)->i_file_acl = 0; | |
ac27a0ec DK |
1616 | |
1617 | cleanup: | |
1618 | brelse(bh); | |
1619 | } | |
1620 | ||
ac27a0ec | 1621 | /* |
617ba13b | 1622 | * ext4_xattr_cache_insert() |
ac27a0ec DK |
1623 | * |
1624 | * Create a new entry in the extended attribute cache, and insert | |
1625 | * it unless such an entry is already in the cache. | |
1626 | * | |
1627 | * Returns 0, or a negative error number on failure. | |
1628 | */ | |
1629 | static void | |
7a2508e1 | 1630 | ext4_xattr_cache_insert(struct mb_cache *ext4_mb_cache, struct buffer_head *bh) |
ac27a0ec | 1631 | { |
6048c64b AG |
1632 | struct ext4_xattr_header *header = BHDR(bh); |
1633 | __u32 hash = le32_to_cpu(header->h_hash); | |
1634 | int reusable = le32_to_cpu(header->h_refcount) < | |
1635 | EXT4_XATTR_REFCOUNT_MAX; | |
ac27a0ec DK |
1636 | int error; |
1637 | ||
7a2508e1 | 1638 | error = mb_cache_entry_create(ext4_mb_cache, GFP_NOFS, hash, |
6048c64b | 1639 | bh->b_blocknr, reusable); |
ac27a0ec | 1640 | if (error) { |
82939d79 | 1641 | if (error == -EBUSY) |
ac27a0ec | 1642 | ea_bdebug(bh, "already in cache"); |
82939d79 | 1643 | } else |
ac27a0ec | 1644 | ea_bdebug(bh, "inserting [%x]", (int)hash); |
ac27a0ec DK |
1645 | } |
1646 | ||
1647 | /* | |
617ba13b | 1648 | * ext4_xattr_cmp() |
ac27a0ec DK |
1649 | * |
1650 | * Compare two extended attribute blocks for equality. | |
1651 | * | |
1652 | * Returns 0 if the blocks are equal, 1 if they differ, and | |
1653 | * a negative error number on errors. | |
1654 | */ | |
1655 | static int | |
617ba13b MC |
1656 | ext4_xattr_cmp(struct ext4_xattr_header *header1, |
1657 | struct ext4_xattr_header *header2) | |
ac27a0ec | 1658 | { |
617ba13b | 1659 | struct ext4_xattr_entry *entry1, *entry2; |
ac27a0ec DK |
1660 | |
1661 | entry1 = ENTRY(header1+1); | |
1662 | entry2 = ENTRY(header2+1); | |
1663 | while (!IS_LAST_ENTRY(entry1)) { | |
1664 | if (IS_LAST_ENTRY(entry2)) | |
1665 | return 1; | |
1666 | if (entry1->e_hash != entry2->e_hash || | |
1667 | entry1->e_name_index != entry2->e_name_index || | |
1668 | entry1->e_name_len != entry2->e_name_len || | |
1669 | entry1->e_value_size != entry2->e_value_size || | |
1670 | memcmp(entry1->e_name, entry2->e_name, entry1->e_name_len)) | |
1671 | return 1; | |
1672 | if (entry1->e_value_block != 0 || entry2->e_value_block != 0) | |
6a797d27 | 1673 | return -EFSCORRUPTED; |
ac27a0ec DK |
1674 | if (memcmp((char *)header1 + le16_to_cpu(entry1->e_value_offs), |
1675 | (char *)header2 + le16_to_cpu(entry2->e_value_offs), | |
1676 | le32_to_cpu(entry1->e_value_size))) | |
1677 | return 1; | |
1678 | ||
617ba13b MC |
1679 | entry1 = EXT4_XATTR_NEXT(entry1); |
1680 | entry2 = EXT4_XATTR_NEXT(entry2); | |
ac27a0ec DK |
1681 | } |
1682 | if (!IS_LAST_ENTRY(entry2)) | |
1683 | return 1; | |
1684 | return 0; | |
1685 | } | |
1686 | ||
1687 | /* | |
617ba13b | 1688 | * ext4_xattr_cache_find() |
ac27a0ec DK |
1689 | * |
1690 | * Find an identical extended attribute block. | |
1691 | * | |
1692 | * Returns a pointer to the block found, or NULL if such a block was | |
1693 | * not found or an error occurred. | |
1694 | */ | |
1695 | static struct buffer_head * | |
617ba13b | 1696 | ext4_xattr_cache_find(struct inode *inode, struct ext4_xattr_header *header, |
7a2508e1 | 1697 | struct mb_cache_entry **pce) |
ac27a0ec DK |
1698 | { |
1699 | __u32 hash = le32_to_cpu(header->h_hash); | |
7a2508e1 JK |
1700 | struct mb_cache_entry *ce; |
1701 | struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode); | |
ac27a0ec DK |
1702 | |
1703 | if (!header->h_hash) | |
1704 | return NULL; /* never share */ | |
1705 | ea_idebug(inode, "looking for cached blocks [%x]", (int)hash); | |
7a2508e1 | 1706 | ce = mb_cache_entry_find_first(ext4_mb_cache, hash); |
ac27a0ec DK |
1707 | while (ce) { |
1708 | struct buffer_head *bh; | |
1709 | ||
ac27a0ec DK |
1710 | bh = sb_bread(inode->i_sb, ce->e_block); |
1711 | if (!bh) { | |
24676da4 TT |
1712 | EXT4_ERROR_INODE(inode, "block %lu read error", |
1713 | (unsigned long) ce->e_block); | |
617ba13b | 1714 | } else if (ext4_xattr_cmp(header, BHDR(bh)) == 0) { |
ac27a0ec DK |
1715 | *pce = ce; |
1716 | return bh; | |
1717 | } | |
1718 | brelse(bh); | |
7a2508e1 | 1719 | ce = mb_cache_entry_find_next(ext4_mb_cache, ce); |
ac27a0ec DK |
1720 | } |
1721 | return NULL; | |
1722 | } | |
1723 | ||
1724 | #define NAME_HASH_SHIFT 5 | |
1725 | #define VALUE_HASH_SHIFT 16 | |
1726 | ||
1727 | /* | |
617ba13b | 1728 | * ext4_xattr_hash_entry() |
ac27a0ec DK |
1729 | * |
1730 | * Compute the hash of an extended attribute. | |
1731 | */ | |
617ba13b MC |
1732 | static inline void ext4_xattr_hash_entry(struct ext4_xattr_header *header, |
1733 | struct ext4_xattr_entry *entry) | |
ac27a0ec DK |
1734 | { |
1735 | __u32 hash = 0; | |
1736 | char *name = entry->e_name; | |
1737 | int n; | |
1738 | ||
2b2d6d01 | 1739 | for (n = 0; n < entry->e_name_len; n++) { |
ac27a0ec DK |
1740 | hash = (hash << NAME_HASH_SHIFT) ^ |
1741 | (hash >> (8*sizeof(hash) - NAME_HASH_SHIFT)) ^ | |
1742 | *name++; | |
1743 | } | |
1744 | ||
1cba4237 | 1745 | if (entry->e_value_size != 0) { |
ac27a0ec DK |
1746 | __le32 *value = (__le32 *)((char *)header + |
1747 | le16_to_cpu(entry->e_value_offs)); | |
1748 | for (n = (le32_to_cpu(entry->e_value_size) + | |
617ba13b | 1749 | EXT4_XATTR_ROUND) >> EXT4_XATTR_PAD_BITS; n; n--) { |
ac27a0ec DK |
1750 | hash = (hash << VALUE_HASH_SHIFT) ^ |
1751 | (hash >> (8*sizeof(hash) - VALUE_HASH_SHIFT)) ^ | |
1752 | le32_to_cpu(*value++); | |
1753 | } | |
1754 | } | |
1755 | entry->e_hash = cpu_to_le32(hash); | |
1756 | } | |
1757 | ||
1758 | #undef NAME_HASH_SHIFT | |
1759 | #undef VALUE_HASH_SHIFT | |
1760 | ||
1761 | #define BLOCK_HASH_SHIFT 16 | |
1762 | ||
1763 | /* | |
617ba13b | 1764 | * ext4_xattr_rehash() |
ac27a0ec DK |
1765 | * |
1766 | * Re-compute the extended attribute hash value after an entry has changed. | |
1767 | */ | |
617ba13b MC |
1768 | static void ext4_xattr_rehash(struct ext4_xattr_header *header, |
1769 | struct ext4_xattr_entry *entry) | |
ac27a0ec | 1770 | { |
617ba13b | 1771 | struct ext4_xattr_entry *here; |
ac27a0ec DK |
1772 | __u32 hash = 0; |
1773 | ||
617ba13b | 1774 | ext4_xattr_hash_entry(header, entry); |
ac27a0ec DK |
1775 | here = ENTRY(header+1); |
1776 | while (!IS_LAST_ENTRY(here)) { | |
1777 | if (!here->e_hash) { | |
1778 | /* Block is not shared if an entry's hash value == 0 */ | |
1779 | hash = 0; | |
1780 | break; | |
1781 | } | |
1782 | hash = (hash << BLOCK_HASH_SHIFT) ^ | |
1783 | (hash >> (8*sizeof(hash) - BLOCK_HASH_SHIFT)) ^ | |
1784 | le32_to_cpu(here->e_hash); | |
617ba13b | 1785 | here = EXT4_XATTR_NEXT(here); |
ac27a0ec DK |
1786 | } |
1787 | header->h_hash = cpu_to_le32(hash); | |
1788 | } | |
1789 | ||
1790 | #undef BLOCK_HASH_SHIFT | |
1791 | ||
9c191f70 M |
1792 | #define HASH_BUCKET_BITS 10 |
1793 | ||
7a2508e1 | 1794 | struct mb_cache * |
82939d79 | 1795 | ext4_xattr_create_cache(void) |
ac27a0ec | 1796 | { |
7a2508e1 | 1797 | return mb_cache_create(HASH_BUCKET_BITS); |
ac27a0ec DK |
1798 | } |
1799 | ||
7a2508e1 | 1800 | void ext4_xattr_destroy_cache(struct mb_cache *cache) |
ac27a0ec | 1801 | { |
9c191f70 | 1802 | if (cache) |
7a2508e1 | 1803 | mb_cache_destroy(cache); |
ac27a0ec | 1804 | } |
9c191f70 | 1805 |