Line data Source code
1 : // SPDX-License-Identifier: GPL-2.0
2 : /*
3 : * linux/fs/ext4/xattr.c
4 : *
5 : * Copyright (C) 2001-2003 Andreas Gruenbacher, <agruen@suse.de>
6 : *
7 : * Fix by Harrison Xing <harrison@mountainviewdata.com>.
8 : * Ext4 code with a lot of help from Eric Jarman <ejarman@acm.org>.
9 : * Extended attributes for symlinks and special files added per
10 : * suggestion of Luka Renko <luka.renko@hermes.si>.
11 : * xattr consolidation Copyright (c) 2004 James Morris <jmorris@redhat.com>,
12 : * Red Hat Inc.
13 : * ea-in-inode support by Alex Tomas <alex@clusterfs.com> aka bzzz
14 : * and Andreas Gruenbacher <agruen@suse.de>.
15 : */
16 :
17 : /*
18 : * Extended attributes are stored directly in inodes (on file systems with
19 : * inodes bigger than 128 bytes) and on additional disk blocks. The i_file_acl
20 : * field contains the block number if an inode uses an additional block. All
21 : * attributes must fit in the inode and one additional block. Blocks that
22 : * contain the identical set of attributes may be shared among several inodes.
23 : * Identical blocks are detected by keeping a cache of blocks that have
24 : * recently been accessed.
25 : *
26 : * The attributes in inodes and on blocks have a different header; the entries
27 : * are stored in the same format:
28 : *
29 : * +------------------+
30 : * | header |
31 : * | entry 1 | |
32 : * | entry 2 | | growing downwards
33 : * | entry 3 | v
34 : * | four null bytes |
35 : * | . . . |
36 : * | value 1 | ^
37 : * | value 3 | | growing upwards
38 : * | value 2 | |
39 : * +------------------+
40 : *
41 : * The header is followed by multiple entry descriptors. In disk blocks, the
42 : * entry descriptors are kept sorted. In inodes, they are unsorted. The
43 : * attribute values are aligned to the end of the block in no specific order.
44 : *
45 : * Locking strategy
46 : * ----------------
47 : * EXT4_I(inode)->i_file_acl is protected by EXT4_I(inode)->xattr_sem.
48 : * EA blocks are only changed if they are exclusive to an inode, so
49 : * holding xattr_sem also means that nothing but the EA block's reference
50 : * count can change. Multiple writers to the same block are synchronized
51 : * by the buffer lock.
52 : */
53 :
54 : #include <linux/init.h>
55 : #include <linux/fs.h>
56 : #include <linux/slab.h>
57 : #include <linux/mbcache.h>
58 : #include <linux/quotaops.h>
59 : #include <linux/iversion.h>
60 : #include "ext4_jbd2.h"
61 : #include "ext4.h"
62 : #include "xattr.h"
63 : #include "acl.h"
64 :
65 : #ifdef EXT4_XATTR_DEBUG
66 : # define ea_idebug(inode, fmt, ...) \
67 : printk(KERN_DEBUG "inode %s:%lu: " fmt "\n", \
68 : inode->i_sb->s_id, inode->i_ino, ##__VA_ARGS__)
69 : # define ea_bdebug(bh, fmt, ...) \
70 : printk(KERN_DEBUG "block %pg:%lu: " fmt "\n", \
71 : bh->b_bdev, (unsigned long)bh->b_blocknr, ##__VA_ARGS__)
72 : #else
73 : # define ea_idebug(inode, fmt, ...) no_printk(fmt, ##__VA_ARGS__)
74 : # define ea_bdebug(bh, fmt, ...) no_printk(fmt, ##__VA_ARGS__)
75 : #endif
76 :
77 : static void ext4_xattr_block_cache_insert(struct mb_cache *,
78 : struct buffer_head *);
79 : static struct buffer_head *
80 : ext4_xattr_block_cache_find(struct inode *, struct ext4_xattr_header *,
81 : struct mb_cache_entry **);
82 : static __le32 ext4_xattr_hash_entry(char *name, size_t name_len, __le32 *value,
83 : size_t value_count);
84 : static void ext4_xattr_rehash(struct ext4_xattr_header *);
85 :
86 : static const struct xattr_handler * const ext4_xattr_handler_map[] = {
87 : [EXT4_XATTR_INDEX_USER] = &ext4_xattr_user_handler,
88 : #ifdef CONFIG_EXT4_FS_POSIX_ACL
89 : [EXT4_XATTR_INDEX_POSIX_ACL_ACCESS] = &posix_acl_access_xattr_handler,
90 : [EXT4_XATTR_INDEX_POSIX_ACL_DEFAULT] = &posix_acl_default_xattr_handler,
91 : #endif
92 : [EXT4_XATTR_INDEX_TRUSTED] = &ext4_xattr_trusted_handler,
93 : #ifdef CONFIG_EXT4_FS_SECURITY
94 : [EXT4_XATTR_INDEX_SECURITY] = &ext4_xattr_security_handler,
95 : #endif
96 : [EXT4_XATTR_INDEX_HURD] = &ext4_xattr_hurd_handler,
97 : };
98 :
99 : const struct xattr_handler *ext4_xattr_handlers[] = {
100 : &ext4_xattr_user_handler,
101 : &ext4_xattr_trusted_handler,
102 : #ifdef CONFIG_EXT4_FS_POSIX_ACL
103 : &posix_acl_access_xattr_handler,
104 : &posix_acl_default_xattr_handler,
105 : #endif
106 : #ifdef CONFIG_EXT4_FS_SECURITY
107 : &ext4_xattr_security_handler,
108 : #endif
109 : &ext4_xattr_hurd_handler,
110 : NULL
111 : };
112 :
113 : #define EA_BLOCK_CACHE(inode) (((struct ext4_sb_info *) \
114 : inode->i_sb->s_fs_info)->s_ea_block_cache)
115 :
116 : #define EA_INODE_CACHE(inode) (((struct ext4_sb_info *) \
117 : inode->i_sb->s_fs_info)->s_ea_inode_cache)
118 :
119 : static int
120 : ext4_expand_inode_array(struct ext4_xattr_inode_array **ea_inode_array,
121 : struct inode *inode);
122 :
123 : #ifdef CONFIG_LOCKDEP
124 0 : void ext4_xattr_inode_set_class(struct inode *ea_inode)
125 : {
126 0 : lockdep_set_subclass(&ea_inode->i_rwsem, 1);
127 0 : }
128 : #endif
129 :
130 0 : static __le32 ext4_xattr_block_csum(struct inode *inode,
131 : sector_t block_nr,
132 : struct ext4_xattr_header *hdr)
133 : {
134 0 : struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
135 0 : __u32 csum;
136 0 : __le64 dsk_block_nr = cpu_to_le64(block_nr);
137 0 : __u32 dummy_csum = 0;
138 0 : int offset = offsetof(struct ext4_xattr_header, h_checksum);
139 :
140 0 : csum = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&dsk_block_nr,
141 : sizeof(dsk_block_nr));
142 0 : csum = ext4_chksum(sbi, csum, (__u8 *)hdr, offset);
143 0 : csum = ext4_chksum(sbi, csum, (__u8 *)&dummy_csum, sizeof(dummy_csum));
144 0 : offset += sizeof(dummy_csum);
145 0 : csum = ext4_chksum(sbi, csum, (__u8 *)hdr + offset,
146 0 : EXT4_BLOCK_SIZE(inode->i_sb) - offset);
147 :
148 0 : return cpu_to_le32(csum);
149 : }
150 :
151 0 : static int ext4_xattr_block_csum_verify(struct inode *inode,
152 : struct buffer_head *bh)
153 : {
154 0 : struct ext4_xattr_header *hdr = BHDR(bh);
155 0 : int ret = 1;
156 :
157 0 : if (ext4_has_metadata_csum(inode->i_sb)) {
158 0 : lock_buffer(bh);
159 0 : ret = (hdr->h_checksum == ext4_xattr_block_csum(inode,
160 : bh->b_blocknr, hdr));
161 0 : unlock_buffer(bh);
162 : }
163 0 : return ret;
164 : }
165 :
166 0 : static void ext4_xattr_block_csum_set(struct inode *inode,
167 : struct buffer_head *bh)
168 : {
169 0 : if (ext4_has_metadata_csum(inode->i_sb))
170 0 : BHDR(bh)->h_checksum = ext4_xattr_block_csum(inode,
171 0 : bh->b_blocknr, BHDR(bh));
172 0 : }
173 :
174 : static inline const struct xattr_handler *
175 0 : ext4_xattr_handler(int name_index)
176 : {
177 0 : const struct xattr_handler *handler = NULL;
178 :
179 0 : if (name_index > 0 && name_index < ARRAY_SIZE(ext4_xattr_handler_map))
180 0 : handler = ext4_xattr_handler_map[name_index];
181 0 : return handler;
182 : }
183 :
184 : static int
185 0 : ext4_xattr_check_entries(struct ext4_xattr_entry *entry, void *end,
186 : void *value_start)
187 : {
188 0 : struct ext4_xattr_entry *e = entry;
189 :
190 : /* Find the end of the names list */
191 0 : while (!IS_LAST_ENTRY(e)) {
192 0 : struct ext4_xattr_entry *next = EXT4_XATTR_NEXT(e);
193 0 : if ((void *)next >= end)
194 : return -EFSCORRUPTED;
195 0 : if (strnlen(e->e_name, e->e_name_len) != e->e_name_len)
196 : return -EFSCORRUPTED;
197 : e = next;
198 : }
199 :
200 : /* Check the values */
201 0 : while (!IS_LAST_ENTRY(entry)) {
202 0 : u32 size = le32_to_cpu(entry->e_value_size);
203 :
204 0 : if (size > EXT4_XATTR_SIZE_MAX)
205 : return -EFSCORRUPTED;
206 :
207 0 : if (size != 0 && entry->e_value_inum == 0) {
208 0 : u16 offs = le16_to_cpu(entry->e_value_offs);
209 0 : void *value;
210 :
211 : /*
212 : * The value cannot overlap the names, and the value
213 : * with padding cannot extend beyond 'end'. Check both
214 : * the padded and unpadded sizes, since the size may
215 : * overflow to 0 when adding padding.
216 : */
217 0 : if (offs > end - value_start)
218 : return -EFSCORRUPTED;
219 0 : value = value_start + offs;
220 0 : if (value < (void *)e + sizeof(u32) ||
221 0 : size > end - value ||
222 0 : EXT4_XATTR_SIZE(size) > end - value)
223 : return -EFSCORRUPTED;
224 : }
225 0 : entry = EXT4_XATTR_NEXT(entry);
226 : }
227 :
228 : return 0;
229 : }
230 :
231 : static inline int
232 0 : __ext4_xattr_check_block(struct inode *inode, struct buffer_head *bh,
233 : const char *function, unsigned int line)
234 : {
235 0 : int error = -EFSCORRUPTED;
236 :
237 0 : if (BHDR(bh)->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC) ||
238 0 : BHDR(bh)->h_blocks != cpu_to_le32(1))
239 0 : goto errout;
240 0 : if (buffer_verified(bh))
241 : return 0;
242 :
243 0 : error = -EFSBADCRC;
244 0 : if (!ext4_xattr_block_csum_verify(inode, bh))
245 0 : goto errout;
246 0 : error = ext4_xattr_check_entries(BFIRST(bh), bh->b_data + bh->b_size,
247 0 : bh->b_data);
248 0 : errout:
249 0 : if (error)
250 0 : __ext4_error_inode(inode, function, line, 0, -error,
251 : "corrupted xattr block %llu",
252 0 : (unsigned long long) bh->b_blocknr);
253 : else
254 0 : set_buffer_verified(bh);
255 : return error;
256 : }
257 :
258 : #define ext4_xattr_check_block(inode, bh) \
259 : __ext4_xattr_check_block((inode), (bh), __func__, __LINE__)
260 :
261 :
262 : static int
263 0 : __xattr_check_inode(struct inode *inode, struct ext4_xattr_ibody_header *header,
264 : void *end, const char *function, unsigned int line)
265 : {
266 0 : int error = -EFSCORRUPTED;
267 :
268 0 : if (end - (void *)header < sizeof(*header) + sizeof(u32) ||
269 0 : (header->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC)))
270 0 : goto errout;
271 0 : error = ext4_xattr_check_entries(IFIRST(header), end, IFIRST(header));
272 0 : errout:
273 0 : if (error)
274 0 : __ext4_error_inode(inode, function, line, 0, -error,
275 : "corrupted in-inode xattr");
276 0 : return error;
277 : }
278 :
279 : #define xattr_check_inode(inode, header, end) \
280 : __xattr_check_inode((inode), (header), (end), __func__, __LINE__)
281 :
282 : static int
283 0 : xattr_find_entry(struct inode *inode, struct ext4_xattr_entry **pentry,
284 : void *end, int name_index, const char *name, int sorted)
285 : {
286 0 : struct ext4_xattr_entry *entry, *next;
287 0 : size_t name_len;
288 0 : int cmp = 1;
289 :
290 0 : if (name == NULL)
291 : return -EINVAL;
292 0 : name_len = strlen(name);
293 0 : for (entry = *pentry; !IS_LAST_ENTRY(entry); entry = next) {
294 0 : next = EXT4_XATTR_NEXT(entry);
295 0 : if ((void *) next >= end) {
296 0 : EXT4_ERROR_INODE(inode, "corrupted xattr entries");
297 0 : return -EFSCORRUPTED;
298 : }
299 0 : cmp = name_index - entry->e_name_index;
300 0 : if (!cmp)
301 0 : cmp = name_len - entry->e_name_len;
302 0 : if (!cmp)
303 0 : cmp = memcmp(name, entry->e_name, name_len);
304 0 : if (cmp <= 0 && (sorted || cmp == 0))
305 : break;
306 : }
307 0 : *pentry = entry;
308 0 : return cmp ? -ENODATA : 0;
309 : }
310 :
311 : static u32
312 0 : ext4_xattr_inode_hash(struct ext4_sb_info *sbi, const void *buffer, size_t size)
313 : {
314 0 : return ext4_chksum(sbi, sbi->s_csum_seed, buffer, size);
315 : }
316 :
317 0 : static u64 ext4_xattr_inode_get_ref(struct inode *ea_inode)
318 : {
319 0 : return ((u64)ea_inode->i_ctime.tv_sec << 32) |
320 0 : (u32) inode_peek_iversion_raw(ea_inode);
321 : }
322 :
323 0 : static void ext4_xattr_inode_set_ref(struct inode *ea_inode, u64 ref_count)
324 : {
325 0 : ea_inode->i_ctime.tv_sec = (u32)(ref_count >> 32);
326 0 : inode_set_iversion_raw(ea_inode, ref_count & 0xffffffff);
327 0 : }
328 :
329 0 : static u32 ext4_xattr_inode_get_hash(struct inode *ea_inode)
330 : {
331 0 : return (u32)ea_inode->i_atime.tv_sec;
332 : }
333 :
334 0 : static void ext4_xattr_inode_set_hash(struct inode *ea_inode, u32 hash)
335 : {
336 0 : ea_inode->i_atime.tv_sec = hash;
337 : }
338 :
339 : /*
340 : * Read the EA value from an inode.
341 : */
342 0 : static int ext4_xattr_inode_read(struct inode *ea_inode, void *buf, size_t size)
343 : {
344 0 : int blocksize = 1 << ea_inode->i_blkbits;
345 0 : int bh_count = (size + blocksize - 1) >> ea_inode->i_blkbits;
346 0 : int tail_size = (size % blocksize) ?: blocksize;
347 0 : struct buffer_head *bhs_inline[8];
348 0 : struct buffer_head **bhs = bhs_inline;
349 0 : int i, ret;
350 :
351 0 : if (bh_count > ARRAY_SIZE(bhs_inline)) {
352 0 : bhs = kmalloc_array(bh_count, sizeof(*bhs), GFP_NOFS);
353 0 : if (!bhs)
354 : return -ENOMEM;
355 : }
356 :
357 0 : ret = ext4_bread_batch(ea_inode, 0 /* block */, bh_count,
358 : true /* wait */, bhs);
359 0 : if (ret)
360 0 : goto free_bhs;
361 :
362 0 : for (i = 0; i < bh_count; i++) {
363 : /* There shouldn't be any holes in ea_inode. */
364 0 : if (!bhs[i]) {
365 0 : ret = -EFSCORRUPTED;
366 0 : goto put_bhs;
367 : }
368 0 : memcpy((char *)buf + blocksize * i, bhs[i]->b_data,
369 0 : i < bh_count - 1 ? blocksize : tail_size);
370 : }
371 : ret = 0;
372 0 : put_bhs:
373 0 : for (i = 0; i < bh_count; i++)
374 0 : brelse(bhs[i]);
375 0 : free_bhs:
376 0 : if (bhs != bhs_inline)
377 0 : kfree(bhs);
378 : return ret;
379 : }
380 :
381 : #define EXT4_XATTR_INODE_GET_PARENT(inode) ((__u32)(inode)->i_mtime.tv_sec)
382 :
383 0 : static int ext4_xattr_inode_iget(struct inode *parent, unsigned long ea_ino,
384 : u32 ea_inode_hash, struct inode **ea_inode)
385 : {
386 0 : struct inode *inode;
387 0 : int err;
388 :
389 0 : inode = ext4_iget(parent->i_sb, ea_ino, EXT4_IGET_NORMAL);
390 0 : if (IS_ERR(inode)) {
391 0 : err = PTR_ERR(inode);
392 0 : ext4_error(parent->i_sb,
393 : "error while reading EA inode %lu err=%d", ea_ino,
394 : err);
395 0 : return err;
396 : }
397 :
398 0 : if (is_bad_inode(inode)) {
399 0 : ext4_error(parent->i_sb,
400 : "error while reading EA inode %lu is_bad_inode",
401 : ea_ino);
402 0 : err = -EIO;
403 0 : goto error;
404 : }
405 :
406 0 : if (!(EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL)) {
407 0 : ext4_error(parent->i_sb,
408 : "EA inode %lu does not have EXT4_EA_INODE_FL flag",
409 : ea_ino);
410 0 : err = -EINVAL;
411 0 : goto error;
412 : }
413 :
414 0 : ext4_xattr_inode_set_class(inode);
415 :
416 : /*
417 : * Check whether this is an old Lustre-style xattr inode. Lustre
418 : * implementation does not have hash validation, rather it has a
419 : * backpointer from ea_inode to the parent inode.
420 : */
421 0 : if (ea_inode_hash != ext4_xattr_inode_get_hash(inode) &&
422 0 : EXT4_XATTR_INODE_GET_PARENT(inode) == parent->i_ino &&
423 0 : inode->i_generation == parent->i_generation) {
424 0 : ext4_set_inode_state(inode, EXT4_STATE_LUSTRE_EA_INODE);
425 0 : ext4_xattr_inode_set_ref(inode, 1);
426 : } else {
427 0 : inode_lock(inode);
428 0 : inode->i_flags |= S_NOQUOTA;
429 0 : inode_unlock(inode);
430 : }
431 :
432 0 : *ea_inode = inode;
433 0 : return 0;
434 0 : error:
435 0 : iput(inode);
436 0 : return err;
437 : }
438 :
439 : static int
440 0 : ext4_xattr_inode_verify_hashes(struct inode *ea_inode,
441 : struct ext4_xattr_entry *entry, void *buffer,
442 : size_t size)
443 : {
444 0 : u32 hash;
445 :
446 : /* Verify stored hash matches calculated hash. */
447 0 : hash = ext4_xattr_inode_hash(EXT4_SB(ea_inode->i_sb), buffer, size);
448 0 : if (hash != ext4_xattr_inode_get_hash(ea_inode))
449 : return -EFSCORRUPTED;
450 :
451 0 : if (entry) {
452 0 : __le32 e_hash, tmp_data;
453 :
454 : /* Verify entry hash. */
455 0 : tmp_data = cpu_to_le32(hash);
456 0 : e_hash = ext4_xattr_hash_entry(entry->e_name, entry->e_name_len,
457 : &tmp_data, 1);
458 0 : if (e_hash != entry->e_hash)
459 0 : return -EFSCORRUPTED;
460 : }
461 : return 0;
462 : }
463 :
464 : /*
465 : * Read xattr value from the EA inode.
466 : */
467 : static int
468 0 : ext4_xattr_inode_get(struct inode *inode, struct ext4_xattr_entry *entry,
469 : void *buffer, size_t size)
470 : {
471 0 : struct mb_cache *ea_inode_cache = EA_INODE_CACHE(inode);
472 0 : struct inode *ea_inode;
473 0 : int err;
474 :
475 0 : err = ext4_xattr_inode_iget(inode, le32_to_cpu(entry->e_value_inum),
476 0 : le32_to_cpu(entry->e_hash), &ea_inode);
477 0 : if (err) {
478 0 : ea_inode = NULL;
479 0 : goto out;
480 : }
481 :
482 0 : if (i_size_read(ea_inode) != size) {
483 0 : ext4_warning_inode(ea_inode,
484 : "ea_inode file size=%llu entry size=%zu",
485 : i_size_read(ea_inode), size);
486 0 : err = -EFSCORRUPTED;
487 0 : goto out;
488 : }
489 :
490 0 : err = ext4_xattr_inode_read(ea_inode, buffer, size);
491 0 : if (err)
492 0 : goto out;
493 :
494 0 : if (!ext4_test_inode_state(ea_inode, EXT4_STATE_LUSTRE_EA_INODE)) {
495 0 : err = ext4_xattr_inode_verify_hashes(ea_inode, entry, buffer,
496 : size);
497 0 : if (err) {
498 0 : ext4_warning_inode(ea_inode,
499 : "EA inode hash validation failed");
500 0 : goto out;
501 : }
502 :
503 0 : if (ea_inode_cache)
504 0 : mb_cache_entry_create(ea_inode_cache, GFP_NOFS,
505 : ext4_xattr_inode_get_hash(ea_inode),
506 0 : ea_inode->i_ino, true /* reusable */);
507 : }
508 0 : out:
509 0 : iput(ea_inode);
510 0 : return err;
511 : }
512 :
513 : static int
514 0 : ext4_xattr_block_get(struct inode *inode, int name_index, const char *name,
515 : void *buffer, size_t buffer_size)
516 : {
517 0 : struct buffer_head *bh = NULL;
518 0 : struct ext4_xattr_entry *entry;
519 0 : size_t size;
520 0 : void *end;
521 0 : int error;
522 0 : struct mb_cache *ea_block_cache = EA_BLOCK_CACHE(inode);
523 :
524 0 : ea_idebug(inode, "name=%d.%s, buffer=%p, buffer_size=%ld",
525 : name_index, name, buffer, (long)buffer_size);
526 :
527 0 : if (!EXT4_I(inode)->i_file_acl)
528 : return -ENODATA;
529 0 : ea_idebug(inode, "reading block %llu",
530 : (unsigned long long)EXT4_I(inode)->i_file_acl);
531 0 : bh = ext4_sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl, REQ_PRIO);
532 0 : if (IS_ERR(bh))
533 0 : return PTR_ERR(bh);
534 0 : ea_bdebug(bh, "b_count=%d, refcount=%d",
535 : atomic_read(&(bh->b_count)), le32_to_cpu(BHDR(bh)->h_refcount));
536 0 : error = ext4_xattr_check_block(inode, bh);
537 0 : if (error)
538 0 : goto cleanup;
539 0 : ext4_xattr_block_cache_insert(ea_block_cache, bh);
540 0 : entry = BFIRST(bh);
541 0 : end = bh->b_data + bh->b_size;
542 0 : error = xattr_find_entry(inode, &entry, end, name_index, name, 1);
543 0 : if (error)
544 0 : goto cleanup;
545 0 : size = le32_to_cpu(entry->e_value_size);
546 0 : error = -ERANGE;
547 0 : if (unlikely(size > EXT4_XATTR_SIZE_MAX))
548 0 : goto cleanup;
549 0 : if (buffer) {
550 0 : if (size > buffer_size)
551 0 : goto cleanup;
552 0 : if (entry->e_value_inum) {
553 0 : error = ext4_xattr_inode_get(inode, entry, buffer,
554 : size);
555 0 : if (error)
556 0 : goto cleanup;
557 : } else {
558 0 : u16 offset = le16_to_cpu(entry->e_value_offs);
559 0 : void *p = bh->b_data + offset;
560 :
561 0 : if (unlikely(p + size > end))
562 0 : goto cleanup;
563 0 : memcpy(buffer, p, size);
564 : }
565 : }
566 0 : error = size;
567 :
568 0 : cleanup:
569 0 : brelse(bh);
570 : return error;
571 : }
572 :
573 : int
574 0 : ext4_xattr_ibody_get(struct inode *inode, int name_index, const char *name,
575 : void *buffer, size_t buffer_size)
576 : {
577 0 : struct ext4_xattr_ibody_header *header;
578 0 : struct ext4_xattr_entry *entry;
579 0 : struct ext4_inode *raw_inode;
580 0 : struct ext4_iloc iloc;
581 0 : size_t size;
582 0 : void *end;
583 0 : int error;
584 :
585 0 : if (!ext4_test_inode_state(inode, EXT4_STATE_XATTR))
586 : return -ENODATA;
587 0 : error = ext4_get_inode_loc(inode, &iloc);
588 0 : if (error)
589 : return error;
590 0 : raw_inode = ext4_raw_inode(&iloc);
591 0 : header = IHDR(inode, raw_inode);
592 0 : end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size;
593 0 : error = xattr_check_inode(inode, header, end);
594 0 : if (error)
595 0 : goto cleanup;
596 0 : entry = IFIRST(header);
597 0 : error = xattr_find_entry(inode, &entry, end, name_index, name, 0);
598 0 : if (error)
599 0 : goto cleanup;
600 0 : size = le32_to_cpu(entry->e_value_size);
601 0 : error = -ERANGE;
602 0 : if (unlikely(size > EXT4_XATTR_SIZE_MAX))
603 0 : goto cleanup;
604 0 : if (buffer) {
605 0 : if (size > buffer_size)
606 0 : goto cleanup;
607 0 : if (entry->e_value_inum) {
608 0 : error = ext4_xattr_inode_get(inode, entry, buffer,
609 : size);
610 0 : if (error)
611 0 : goto cleanup;
612 : } else {
613 0 : u16 offset = le16_to_cpu(entry->e_value_offs);
614 0 : void *p = (void *)IFIRST(header) + offset;
615 :
616 0 : if (unlikely(p + size > end))
617 0 : goto cleanup;
618 0 : memcpy(buffer, p, size);
619 : }
620 : }
621 0 : error = size;
622 :
623 0 : cleanup:
624 0 : brelse(iloc.bh);
625 : return error;
626 : }
627 :
628 : /*
629 : * ext4_xattr_get()
630 : *
631 : * Copy an extended attribute into the buffer
632 : * provided, or compute the buffer size required.
633 : * Buffer is NULL to compute the size of the buffer required.
634 : *
635 : * Returns a negative error number on failure, or the number of bytes
636 : * used / required on success.
637 : */
638 : int
639 0 : ext4_xattr_get(struct inode *inode, int name_index, const char *name,
640 : void *buffer, size_t buffer_size)
641 : {
642 0 : int error;
643 :
644 0 : if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
645 : return -EIO;
646 :
647 0 : if (strlen(name) > 255)
648 : return -ERANGE;
649 :
650 0 : down_read(&EXT4_I(inode)->xattr_sem);
651 0 : error = ext4_xattr_ibody_get(inode, name_index, name, buffer,
652 : buffer_size);
653 0 : if (error == -ENODATA)
654 0 : error = ext4_xattr_block_get(inode, name_index, name, buffer,
655 : buffer_size);
656 0 : up_read(&EXT4_I(inode)->xattr_sem);
657 0 : return error;
658 : }
659 :
660 : static int
661 0 : ext4_xattr_list_entries(struct dentry *dentry, struct ext4_xattr_entry *entry,
662 : char *buffer, size_t buffer_size)
663 : {
664 0 : size_t rest = buffer_size;
665 :
666 0 : for (; !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) {
667 0 : const struct xattr_handler *handler =
668 0 : ext4_xattr_handler(entry->e_name_index);
669 :
670 0 : if (handler && (!handler->list || handler->list(dentry))) {
671 0 : const char *prefix = handler->prefix ?: handler->name;
672 0 : size_t prefix_len = strlen(prefix);
673 0 : size_t size = prefix_len + entry->e_name_len + 1;
674 :
675 0 : if (buffer) {
676 0 : if (size > rest)
677 : return -ERANGE;
678 0 : memcpy(buffer, prefix, prefix_len);
679 0 : buffer += prefix_len;
680 0 : memcpy(buffer, entry->e_name, entry->e_name_len);
681 0 : buffer += entry->e_name_len;
682 0 : *buffer++ = 0;
683 : }
684 0 : rest -= size;
685 : }
686 : }
687 0 : return buffer_size - rest; /* total size */
688 : }
689 :
690 : static int
691 0 : ext4_xattr_block_list(struct dentry *dentry, char *buffer, size_t buffer_size)
692 : {
693 0 : struct inode *inode = d_inode(dentry);
694 0 : struct buffer_head *bh = NULL;
695 0 : int error;
696 :
697 0 : ea_idebug(inode, "buffer=%p, buffer_size=%ld",
698 : buffer, (long)buffer_size);
699 :
700 0 : if (!EXT4_I(inode)->i_file_acl)
701 : return 0;
702 0 : ea_idebug(inode, "reading block %llu",
703 : (unsigned long long)EXT4_I(inode)->i_file_acl);
704 0 : bh = ext4_sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl, REQ_PRIO);
705 0 : if (IS_ERR(bh))
706 0 : return PTR_ERR(bh);
707 0 : ea_bdebug(bh, "b_count=%d, refcount=%d",
708 : atomic_read(&(bh->b_count)), le32_to_cpu(BHDR(bh)->h_refcount));
709 0 : error = ext4_xattr_check_block(inode, bh);
710 0 : if (error)
711 0 : goto cleanup;
712 0 : ext4_xattr_block_cache_insert(EA_BLOCK_CACHE(inode), bh);
713 0 : error = ext4_xattr_list_entries(dentry, BFIRST(bh), buffer,
714 : buffer_size);
715 0 : cleanup:
716 0 : brelse(bh);
717 : return error;
718 : }
719 :
720 : static int
721 0 : ext4_xattr_ibody_list(struct dentry *dentry, char *buffer, size_t buffer_size)
722 : {
723 0 : struct inode *inode = d_inode(dentry);
724 0 : struct ext4_xattr_ibody_header *header;
725 0 : struct ext4_inode *raw_inode;
726 0 : struct ext4_iloc iloc;
727 0 : void *end;
728 0 : int error;
729 :
730 0 : if (!ext4_test_inode_state(inode, EXT4_STATE_XATTR))
731 : return 0;
732 0 : error = ext4_get_inode_loc(inode, &iloc);
733 0 : if (error)
734 : return error;
735 0 : raw_inode = ext4_raw_inode(&iloc);
736 0 : header = IHDR(inode, raw_inode);
737 0 : end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size;
738 0 : error = xattr_check_inode(inode, header, end);
739 0 : if (error)
740 0 : goto cleanup;
741 0 : error = ext4_xattr_list_entries(dentry, IFIRST(header),
742 : buffer, buffer_size);
743 :
744 0 : cleanup:
745 0 : brelse(iloc.bh);
746 : return error;
747 : }
748 :
749 : /*
750 : * Inode operation listxattr()
751 : *
752 : * d_inode(dentry)->i_rwsem: don't care
753 : *
754 : * Copy a list of attribute names into the buffer
755 : * provided, or compute the buffer size required.
756 : * Buffer is NULL to compute the size of the buffer required.
757 : *
758 : * Returns a negative error number on failure, or the number of bytes
759 : * used / required on success.
760 : */
761 : ssize_t
762 0 : ext4_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size)
763 : {
764 0 : int ret, ret2;
765 :
766 0 : down_read(&EXT4_I(d_inode(dentry))->xattr_sem);
767 0 : ret = ret2 = ext4_xattr_ibody_list(dentry, buffer, buffer_size);
768 0 : if (ret < 0)
769 0 : goto errout;
770 0 : if (buffer) {
771 0 : buffer += ret;
772 0 : buffer_size -= ret;
773 : }
774 0 : ret = ext4_xattr_block_list(dentry, buffer, buffer_size);
775 0 : if (ret < 0)
776 0 : goto errout;
777 0 : ret += ret2;
778 0 : errout:
779 0 : up_read(&EXT4_I(d_inode(dentry))->xattr_sem);
780 0 : return ret;
781 : }
782 :
783 : /*
784 : * If the EXT4_FEATURE_COMPAT_EXT_ATTR feature of this file system is
785 : * not set, set it.
786 : */
787 0 : static void ext4_xattr_update_super_block(handle_t *handle,
788 : struct super_block *sb)
789 : {
790 0 : if (ext4_has_feature_xattr(sb))
791 : return;
792 :
793 0 : BUFFER_TRACE(EXT4_SB(sb)->s_sbh, "get_write_access");
794 0 : if (ext4_journal_get_write_access(handle, EXT4_SB(sb)->s_sbh) == 0) {
795 0 : lock_buffer(EXT4_SB(sb)->s_sbh);
796 0 : ext4_set_feature_xattr(sb);
797 0 : ext4_superblock_csum_set(sb);
798 0 : unlock_buffer(EXT4_SB(sb)->s_sbh);
799 0 : ext4_handle_dirty_metadata(handle, NULL, EXT4_SB(sb)->s_sbh);
800 : }
801 : }
802 :
803 0 : int ext4_get_inode_usage(struct inode *inode, qsize_t *usage)
804 : {
805 0 : struct ext4_iloc iloc = { .bh = NULL };
806 0 : struct buffer_head *bh = NULL;
807 0 : struct ext4_inode *raw_inode;
808 0 : struct ext4_xattr_ibody_header *header;
809 0 : struct ext4_xattr_entry *entry;
810 0 : qsize_t ea_inode_refs = 0;
811 0 : void *end;
812 0 : int ret;
813 :
814 0 : lockdep_assert_held_read(&EXT4_I(inode)->xattr_sem);
815 :
816 0 : if (ext4_test_inode_state(inode, EXT4_STATE_XATTR)) {
817 0 : ret = ext4_get_inode_loc(inode, &iloc);
818 0 : if (ret)
819 0 : goto out;
820 0 : raw_inode = ext4_raw_inode(&iloc);
821 0 : header = IHDR(inode, raw_inode);
822 0 : end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size;
823 0 : ret = xattr_check_inode(inode, header, end);
824 0 : if (ret)
825 0 : goto out;
826 :
827 0 : for (entry = IFIRST(header); !IS_LAST_ENTRY(entry);
828 0 : entry = EXT4_XATTR_NEXT(entry))
829 0 : if (entry->e_value_inum)
830 0 : ea_inode_refs++;
831 : }
832 :
833 0 : if (EXT4_I(inode)->i_file_acl) {
834 0 : bh = ext4_sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl, REQ_PRIO);
835 0 : if (IS_ERR(bh)) {
836 0 : ret = PTR_ERR(bh);
837 0 : bh = NULL;
838 0 : goto out;
839 : }
840 :
841 0 : ret = ext4_xattr_check_block(inode, bh);
842 0 : if (ret)
843 0 : goto out;
844 :
845 0 : for (entry = BFIRST(bh); !IS_LAST_ENTRY(entry);
846 0 : entry = EXT4_XATTR_NEXT(entry))
847 0 : if (entry->e_value_inum)
848 0 : ea_inode_refs++;
849 : }
850 0 : *usage = ea_inode_refs + 1;
851 0 : ret = 0;
852 0 : out:
853 0 : brelse(iloc.bh);
854 0 : brelse(bh);
855 0 : return ret;
856 : }
857 :
858 0 : static inline size_t round_up_cluster(struct inode *inode, size_t length)
859 : {
860 0 : struct super_block *sb = inode->i_sb;
861 0 : size_t cluster_size = 1 << (EXT4_SB(sb)->s_cluster_bits +
862 0 : inode->i_blkbits);
863 0 : size_t mask = ~(cluster_size - 1);
864 :
865 0 : return (length + cluster_size - 1) & mask;
866 : }
867 :
868 0 : static int ext4_xattr_inode_alloc_quota(struct inode *inode, size_t len)
869 : {
870 0 : int err;
871 :
872 0 : err = dquot_alloc_inode(inode);
873 0 : if (err)
874 : return err;
875 0 : err = dquot_alloc_space_nodirty(inode, round_up_cluster(inode, len));
876 0 : if (err)
877 0 : dquot_free_inode(inode);
878 0 : return err;
879 : }
880 :
881 0 : static void ext4_xattr_inode_free_quota(struct inode *parent,
882 : struct inode *ea_inode,
883 : size_t len)
884 : {
885 0 : if (ea_inode &&
886 0 : ext4_test_inode_state(ea_inode, EXT4_STATE_LUSTRE_EA_INODE))
887 : return;
888 0 : dquot_free_space_nodirty(parent, round_up_cluster(parent, len));
889 0 : dquot_free_inode(parent);
890 : }
891 :
892 644 : int __ext4_xattr_set_credits(struct super_block *sb, struct inode *inode,
893 : struct buffer_head *block_bh, size_t value_len,
894 : bool is_create)
895 : {
896 644 : int credits;
897 644 : int blocks;
898 :
899 : /*
900 : * 1) Owner inode update
901 : * 2) Ref count update on old xattr block
902 : * 3) new xattr block
903 : * 4) block bitmap update for new xattr block
904 : * 5) group descriptor for new xattr block
905 : * 6) block bitmap update for old xattr block
906 : * 7) group descriptor for old block
907 : *
908 : * 6 & 7 can happen if we have two racing threads T_a and T_b
909 : * which are each trying to set an xattr on inodes I_a and I_b
910 : * which were both initially sharing an xattr block.
911 : */
912 644 : credits = 7;
913 :
914 : /* Quota updates. */
915 644 : credits += EXT4_MAXQUOTAS_TRANS_BLOCKS(sb);
916 :
917 : /*
918 : * In case of inline data, we may push out the data to a block,
919 : * so we need to reserve credits for this eventuality
920 : */
921 644 : if (inode && ext4_has_inline_data(inode))
922 0 : credits += ext4_writepage_trans_blocks(inode) + 1;
923 :
924 : /* We are done if ea_inode feature is not enabled. */
925 644 : if (!ext4_has_feature_ea_inode(sb))
926 : return credits;
927 :
928 : /* New ea_inode, inode map, block bitmap, group descriptor. */
929 0 : credits += 4;
930 :
931 : /* Data blocks. */
932 0 : blocks = (value_len + sb->s_blocksize - 1) >> sb->s_blocksize_bits;
933 :
934 : /* Indirection block or one level of extent tree. */
935 0 : blocks += 1;
936 :
937 : /* Block bitmap and group descriptor updates for each block. */
938 0 : credits += blocks * 2;
939 :
940 : /* Blocks themselves. */
941 0 : credits += blocks;
942 :
943 0 : if (!is_create) {
944 : /* Dereference ea_inode holding old xattr value.
945 : * Old ea_inode, inode map, block bitmap, group descriptor.
946 : */
947 0 : credits += 4;
948 :
949 : /* Data blocks for old ea_inode. */
950 0 : blocks = XATTR_SIZE_MAX >> sb->s_blocksize_bits;
951 :
952 : /* Indirection block or one level of extent tree for old
953 : * ea_inode.
954 : */
955 0 : blocks += 1;
956 :
957 : /* Block bitmap and group descriptor updates for each block. */
958 0 : credits += blocks * 2;
959 : }
960 :
961 : /* We may need to clone the existing xattr block in which case we need
962 : * to increment ref counts for existing ea_inodes referenced by it.
963 : */
964 0 : if (block_bh) {
965 0 : struct ext4_xattr_entry *entry = BFIRST(block_bh);
966 :
967 0 : for (; !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry))
968 0 : if (entry->e_value_inum)
969 : /* Ref count update on ea_inode. */
970 0 : credits += 1;
971 : }
972 : return credits;
973 : }
974 :
975 0 : static int ext4_xattr_inode_update_ref(handle_t *handle, struct inode *ea_inode,
976 : int ref_change)
977 : {
978 0 : struct mb_cache *ea_inode_cache = EA_INODE_CACHE(ea_inode);
979 0 : struct ext4_iloc iloc;
980 0 : s64 ref_count;
981 0 : u32 hash;
982 0 : int ret;
983 :
984 0 : inode_lock(ea_inode);
985 :
986 0 : ret = ext4_reserve_inode_write(handle, ea_inode, &iloc);
987 0 : if (ret)
988 0 : goto out;
989 :
990 0 : ref_count = ext4_xattr_inode_get_ref(ea_inode);
991 0 : ref_count += ref_change;
992 0 : ext4_xattr_inode_set_ref(ea_inode, ref_count);
993 :
994 0 : if (ref_change > 0) {
995 0 : WARN_ONCE(ref_count <= 0, "EA inode %lu ref_count=%lld",
996 : ea_inode->i_ino, ref_count);
997 :
998 0 : if (ref_count == 1) {
999 0 : WARN_ONCE(ea_inode->i_nlink, "EA inode %lu i_nlink=%u",
1000 : ea_inode->i_ino, ea_inode->i_nlink);
1001 :
1002 0 : set_nlink(ea_inode, 1);
1003 0 : ext4_orphan_del(handle, ea_inode);
1004 :
1005 0 : if (ea_inode_cache) {
1006 0 : hash = ext4_xattr_inode_get_hash(ea_inode);
1007 0 : mb_cache_entry_create(ea_inode_cache,
1008 : GFP_NOFS, hash,
1009 0 : ea_inode->i_ino,
1010 : true /* reusable */);
1011 : }
1012 : }
1013 : } else {
1014 0 : WARN_ONCE(ref_count < 0, "EA inode %lu ref_count=%lld",
1015 : ea_inode->i_ino, ref_count);
1016 :
1017 0 : if (ref_count == 0) {
1018 0 : WARN_ONCE(ea_inode->i_nlink != 1,
1019 : "EA inode %lu i_nlink=%u",
1020 : ea_inode->i_ino, ea_inode->i_nlink);
1021 :
1022 0 : clear_nlink(ea_inode);
1023 0 : ext4_orphan_add(handle, ea_inode);
1024 :
1025 0 : if (ea_inode_cache) {
1026 0 : hash = ext4_xattr_inode_get_hash(ea_inode);
1027 0 : mb_cache_entry_delete(ea_inode_cache, hash,
1028 0 : ea_inode->i_ino);
1029 : }
1030 : }
1031 : }
1032 :
1033 0 : ret = ext4_mark_iloc_dirty(handle, ea_inode, &iloc);
1034 0 : if (ret)
1035 0 : ext4_warning_inode(ea_inode,
1036 : "ext4_mark_iloc_dirty() failed ret=%d", ret);
1037 0 : out:
1038 0 : inode_unlock(ea_inode);
1039 0 : return ret;
1040 : }
1041 :
1042 0 : static int ext4_xattr_inode_inc_ref(handle_t *handle, struct inode *ea_inode)
1043 : {
1044 0 : return ext4_xattr_inode_update_ref(handle, ea_inode, 1);
1045 : }
1046 :
1047 0 : static int ext4_xattr_inode_dec_ref(handle_t *handle, struct inode *ea_inode)
1048 : {
1049 0 : return ext4_xattr_inode_update_ref(handle, ea_inode, -1);
1050 : }
1051 :
1052 0 : static int ext4_xattr_inode_inc_ref_all(handle_t *handle, struct inode *parent,
1053 : struct ext4_xattr_entry *first)
1054 : {
1055 0 : struct inode *ea_inode;
1056 0 : struct ext4_xattr_entry *entry;
1057 0 : struct ext4_xattr_entry *failed_entry;
1058 0 : unsigned int ea_ino;
1059 0 : int err, saved_err;
1060 :
1061 0 : for (entry = first; !IS_LAST_ENTRY(entry);
1062 0 : entry = EXT4_XATTR_NEXT(entry)) {
1063 0 : if (!entry->e_value_inum)
1064 0 : continue;
1065 0 : ea_ino = le32_to_cpu(entry->e_value_inum);
1066 0 : err = ext4_xattr_inode_iget(parent, ea_ino,
1067 0 : le32_to_cpu(entry->e_hash),
1068 : &ea_inode);
1069 0 : if (err)
1070 0 : goto cleanup;
1071 0 : err = ext4_xattr_inode_inc_ref(handle, ea_inode);
1072 0 : if (err) {
1073 0 : ext4_warning_inode(ea_inode, "inc ref error %d", err);
1074 0 : iput(ea_inode);
1075 0 : goto cleanup;
1076 : }
1077 0 : iput(ea_inode);
1078 : }
1079 : return 0;
1080 :
1081 0 : cleanup:
1082 0 : saved_err = err;
1083 0 : failed_entry = entry;
1084 :
1085 0 : for (entry = first; entry != failed_entry;
1086 0 : entry = EXT4_XATTR_NEXT(entry)) {
1087 0 : if (!entry->e_value_inum)
1088 0 : continue;
1089 0 : ea_ino = le32_to_cpu(entry->e_value_inum);
1090 0 : err = ext4_xattr_inode_iget(parent, ea_ino,
1091 0 : le32_to_cpu(entry->e_hash),
1092 : &ea_inode);
1093 0 : if (err) {
1094 0 : ext4_warning(parent->i_sb,
1095 : "cleanup ea_ino %u iget error %d", ea_ino,
1096 : err);
1097 0 : continue;
1098 : }
1099 0 : err = ext4_xattr_inode_dec_ref(handle, ea_inode);
1100 0 : if (err)
1101 0 : ext4_warning_inode(ea_inode, "cleanup dec ref error %d",
1102 : err);
1103 0 : iput(ea_inode);
1104 : }
1105 : return saved_err;
1106 : }
1107 :
1108 0 : static int ext4_xattr_restart_fn(handle_t *handle, struct inode *inode,
1109 : struct buffer_head *bh, bool block_csum, bool dirty)
1110 : {
1111 0 : int error;
1112 :
1113 0 : if (bh && dirty) {
1114 0 : if (block_csum)
1115 0 : ext4_xattr_block_csum_set(inode, bh);
1116 0 : error = ext4_handle_dirty_metadata(handle, NULL, bh);
1117 0 : if (error) {
1118 0 : ext4_warning(inode->i_sb, "Handle metadata (error %d)",
1119 : error);
1120 0 : return error;
1121 : }
1122 : }
1123 : return 0;
1124 : }
1125 :
1126 : static void
1127 0 : ext4_xattr_inode_dec_ref_all(handle_t *handle, struct inode *parent,
1128 : struct buffer_head *bh,
1129 : struct ext4_xattr_entry *first, bool block_csum,
1130 : struct ext4_xattr_inode_array **ea_inode_array,
1131 : int extra_credits, bool skip_quota)
1132 : {
1133 0 : struct inode *ea_inode;
1134 0 : struct ext4_xattr_entry *entry;
1135 0 : bool dirty = false;
1136 0 : unsigned int ea_ino;
1137 0 : int err;
1138 0 : int credits;
1139 :
1140 : /* One credit for dec ref on ea_inode, one for orphan list addition, */
1141 0 : credits = 2 + extra_credits;
1142 :
1143 0 : for (entry = first; !IS_LAST_ENTRY(entry);
1144 0 : entry = EXT4_XATTR_NEXT(entry)) {
1145 0 : if (!entry->e_value_inum)
1146 0 : continue;
1147 0 : ea_ino = le32_to_cpu(entry->e_value_inum);
1148 0 : err = ext4_xattr_inode_iget(parent, ea_ino,
1149 0 : le32_to_cpu(entry->e_hash),
1150 : &ea_inode);
1151 0 : if (err)
1152 0 : continue;
1153 :
1154 0 : err = ext4_expand_inode_array(ea_inode_array, ea_inode);
1155 0 : if (err) {
1156 0 : ext4_warning_inode(ea_inode,
1157 : "Expand inode array err=%d", err);
1158 0 : iput(ea_inode);
1159 0 : continue;
1160 : }
1161 :
1162 0 : err = ext4_journal_ensure_credits_fn(handle, credits, credits,
1163 : ext4_free_metadata_revoke_credits(parent->i_sb, 1),
1164 : ext4_xattr_restart_fn(handle, parent, bh, block_csum,
1165 : dirty));
1166 0 : if (err < 0) {
1167 0 : ext4_warning_inode(ea_inode, "Ensure credits err=%d",
1168 : err);
1169 0 : continue;
1170 : }
1171 0 : if (err > 0) {
1172 0 : err = ext4_journal_get_write_access(handle, bh);
1173 0 : if (err) {
1174 0 : ext4_warning_inode(ea_inode,
1175 : "Re-get write access err=%d",
1176 : err);
1177 0 : continue;
1178 : }
1179 : }
1180 :
1181 0 : err = ext4_xattr_inode_dec_ref(handle, ea_inode);
1182 0 : if (err) {
1183 0 : ext4_warning_inode(ea_inode, "ea_inode dec ref err=%d",
1184 : err);
1185 0 : continue;
1186 : }
1187 :
1188 0 : if (!skip_quota)
1189 0 : ext4_xattr_inode_free_quota(parent, ea_inode,
1190 0 : le32_to_cpu(entry->e_value_size));
1191 :
1192 : /*
1193 : * Forget about ea_inode within the same transaction that
1194 : * decrements the ref count. This avoids duplicate decrements in
1195 : * case the rest of the work spills over to subsequent
1196 : * transactions.
1197 : */
1198 0 : entry->e_value_inum = 0;
1199 0 : entry->e_value_size = 0;
1200 :
1201 0 : dirty = true;
1202 : }
1203 :
1204 0 : if (dirty) {
1205 : /*
1206 : * Note that we are deliberately skipping csum calculation for
1207 : * the final update because we do not expect any journal
1208 : * restarts until xattr block is freed.
1209 : */
1210 :
1211 0 : err = ext4_handle_dirty_metadata(handle, NULL, bh);
1212 0 : if (err)
1213 0 : ext4_warning_inode(parent,
1214 : "handle dirty metadata err=%d", err);
1215 : }
1216 0 : }
1217 :
1218 : /*
1219 : * Release the xattr block BH: If the reference count is > 1, decrement it;
1220 : * otherwise free the block.
1221 : */
1222 : static void
1223 0 : ext4_xattr_release_block(handle_t *handle, struct inode *inode,
1224 : struct buffer_head *bh,
1225 : struct ext4_xattr_inode_array **ea_inode_array,
1226 : int extra_credits)
1227 : {
1228 0 : struct mb_cache *ea_block_cache = EA_BLOCK_CACHE(inode);
1229 0 : u32 hash, ref;
1230 0 : int error = 0;
1231 :
1232 0 : BUFFER_TRACE(bh, "get_write_access");
1233 0 : error = ext4_journal_get_write_access(handle, bh);
1234 0 : if (error)
1235 0 : goto out;
1236 :
1237 0 : lock_buffer(bh);
1238 0 : hash = le32_to_cpu(BHDR(bh)->h_hash);
1239 0 : ref = le32_to_cpu(BHDR(bh)->h_refcount);
1240 0 : if (ref == 1) {
1241 0 : ea_bdebug(bh, "refcount now=0; freeing");
1242 : /*
1243 : * This must happen under buffer lock for
1244 : * ext4_xattr_block_set() to reliably detect freed block
1245 : */
1246 0 : if (ea_block_cache)
1247 0 : mb_cache_entry_delete(ea_block_cache, hash,
1248 : bh->b_blocknr);
1249 0 : get_bh(bh);
1250 0 : unlock_buffer(bh);
1251 :
1252 0 : if (ext4_has_feature_ea_inode(inode->i_sb))
1253 0 : ext4_xattr_inode_dec_ref_all(handle, inode, bh,
1254 0 : BFIRST(bh),
1255 : true /* block_csum */,
1256 : ea_inode_array,
1257 : extra_credits,
1258 : true /* skip_quota */);
1259 0 : ext4_free_blocks(handle, inode, bh, 0, 1,
1260 : EXT4_FREE_BLOCKS_METADATA |
1261 : EXT4_FREE_BLOCKS_FORGET);
1262 : } else {
1263 0 : ref--;
1264 0 : BHDR(bh)->h_refcount = cpu_to_le32(ref);
1265 0 : if (ref == EXT4_XATTR_REFCOUNT_MAX - 1) {
1266 0 : struct mb_cache_entry *ce;
1267 :
1268 0 : if (ea_block_cache) {
1269 0 : ce = mb_cache_entry_get(ea_block_cache, hash,
1270 : bh->b_blocknr);
1271 0 : if (ce) {
1272 0 : ce->e_reusable = 1;
1273 0 : mb_cache_entry_put(ea_block_cache, ce);
1274 : }
1275 : }
1276 : }
1277 :
1278 0 : ext4_xattr_block_csum_set(inode, bh);
1279 : /*
1280 : * Beware of this ugliness: Releasing of xattr block references
1281 : * from different inodes can race and so we have to protect
1282 : * from a race where someone else frees the block (and releases
1283 : * its journal_head) before we are done dirtying the buffer. In
1284 : * nojournal mode this race is harmless and we actually cannot
1285 : * call ext4_handle_dirty_metadata() with locked buffer as
1286 : * that function can call sync_dirty_buffer() so for that case
1287 : * we handle the dirtying after unlocking the buffer.
1288 : */
1289 0 : if (ext4_handle_valid(handle))
1290 0 : error = ext4_handle_dirty_metadata(handle, inode, bh);
1291 0 : unlock_buffer(bh);
1292 0 : if (!ext4_handle_valid(handle))
1293 0 : error = ext4_handle_dirty_metadata(handle, inode, bh);
1294 0 : if (IS_SYNC(inode))
1295 0 : ext4_handle_sync(handle);
1296 0 : dquot_free_block(inode, EXT4_C2B(EXT4_SB(inode->i_sb), 1));
1297 0 : ea_bdebug(bh, "refcount now=%d; releasing",
1298 : le32_to_cpu(BHDR(bh)->h_refcount));
1299 : }
1300 0 : out:
1301 0 : ext4_std_error(inode->i_sb, error);
1302 0 : return;
1303 : }
1304 :
1305 : /*
1306 : * Find the available free space for EAs. This also returns the total number of
1307 : * bytes used by EA entries.
1308 : */
1309 0 : static size_t ext4_xattr_free_space(struct ext4_xattr_entry *last,
1310 : size_t *min_offs, void *base, int *total)
1311 : {
1312 0 : for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) {
1313 0 : if (!last->e_value_inum && last->e_value_size) {
1314 0 : size_t offs = le16_to_cpu(last->e_value_offs);
1315 0 : if (offs < *min_offs)
1316 0 : *min_offs = offs;
1317 : }
1318 0 : if (total)
1319 0 : *total += EXT4_XATTR_LEN(last->e_name_len);
1320 : }
1321 0 : return (*min_offs - ((void *)last - base) - sizeof(__u32));
1322 : }
1323 :
1324 : /*
1325 : * Write the value of the EA in an inode.
1326 : */
1327 0 : static int ext4_xattr_inode_write(handle_t *handle, struct inode *ea_inode,
1328 : const void *buf, int bufsize)
1329 : {
1330 0 : struct buffer_head *bh = NULL;
1331 0 : unsigned long block = 0;
1332 0 : int blocksize = ea_inode->i_sb->s_blocksize;
1333 0 : int max_blocks = (bufsize + blocksize - 1) >> ea_inode->i_blkbits;
1334 0 : int csize, wsize = 0;
1335 0 : int ret = 0, ret2 = 0;
1336 0 : int retries = 0;
1337 :
1338 : retry:
1339 0 : while (ret >= 0 && ret < max_blocks) {
1340 0 : struct ext4_map_blocks map;
1341 0 : map.m_lblk = block += ret;
1342 0 : map.m_len = max_blocks -= ret;
1343 :
1344 0 : ret = ext4_map_blocks(handle, ea_inode, &map,
1345 : EXT4_GET_BLOCKS_CREATE);
1346 0 : if (ret <= 0) {
1347 0 : ext4_mark_inode_dirty(handle, ea_inode);
1348 0 : if (ret == -ENOSPC &&
1349 0 : ext4_should_retry_alloc(ea_inode->i_sb, &retries)) {
1350 0 : ret = 0;
1351 0 : goto retry;
1352 : }
1353 0 : break;
1354 : }
1355 : }
1356 :
1357 0 : if (ret < 0)
1358 : return ret;
1359 :
1360 : block = 0;
1361 0 : while (wsize < bufsize) {
1362 0 : brelse(bh);
1363 0 : csize = (bufsize - wsize) > blocksize ? blocksize :
1364 : bufsize - wsize;
1365 0 : bh = ext4_getblk(handle, ea_inode, block, 0);
1366 0 : if (IS_ERR(bh))
1367 0 : return PTR_ERR(bh);
1368 0 : if (!bh) {
1369 0 : WARN_ON_ONCE(1);
1370 0 : EXT4_ERROR_INODE(ea_inode,
1371 : "ext4_getblk() return bh = NULL");
1372 0 : return -EFSCORRUPTED;
1373 : }
1374 0 : ret = ext4_journal_get_write_access(handle, bh);
1375 0 : if (ret)
1376 0 : goto out;
1377 :
1378 0 : memcpy(bh->b_data, buf, csize);
1379 0 : set_buffer_uptodate(bh);
1380 0 : ext4_handle_dirty_metadata(handle, ea_inode, bh);
1381 :
1382 0 : buf += csize;
1383 0 : wsize += csize;
1384 0 : block += 1;
1385 : }
1386 :
1387 0 : inode_lock(ea_inode);
1388 0 : i_size_write(ea_inode, wsize);
1389 0 : ext4_update_i_disksize(ea_inode, wsize);
1390 0 : inode_unlock(ea_inode);
1391 :
1392 0 : ret2 = ext4_mark_inode_dirty(handle, ea_inode);
1393 0 : if (unlikely(ret2 && !ret))
1394 0 : ret = ret2;
1395 :
1396 0 : out:
1397 0 : brelse(bh);
1398 :
1399 : return ret;
1400 : }
1401 :
1402 : /*
1403 : * Create an inode to store the value of a large EA.
1404 : */
1405 0 : static struct inode *ext4_xattr_inode_create(handle_t *handle,
1406 : struct inode *inode, u32 hash)
1407 : {
1408 0 : struct inode *ea_inode = NULL;
1409 0 : uid_t owner[2] = { i_uid_read(inode), i_gid_read(inode) };
1410 0 : int err;
1411 :
1412 : /*
1413 : * Let the next inode be the goal, so we try and allocate the EA inode
1414 : * in the same group, or nearby one.
1415 : */
1416 0 : ea_inode = ext4_new_inode(handle, inode->i_sb->s_root->d_inode,
1417 : S_IFREG | 0600, NULL, inode->i_ino + 1, owner,
1418 : EXT4_EA_INODE_FL);
1419 0 : if (!IS_ERR(ea_inode)) {
1420 0 : ea_inode->i_op = &ext4_file_inode_operations;
1421 0 : ea_inode->i_fop = &ext4_file_operations;
1422 0 : ext4_set_aops(ea_inode);
1423 0 : ext4_xattr_inode_set_class(ea_inode);
1424 0 : unlock_new_inode(ea_inode);
1425 0 : ext4_xattr_inode_set_ref(ea_inode, 1);
1426 0 : ext4_xattr_inode_set_hash(ea_inode, hash);
1427 0 : err = ext4_mark_inode_dirty(handle, ea_inode);
1428 0 : if (!err)
1429 0 : err = ext4_inode_attach_jinode(ea_inode);
1430 0 : if (err) {
1431 0 : iput(ea_inode);
1432 0 : return ERR_PTR(err);
1433 : }
1434 :
1435 : /*
1436 : * Xattr inodes are shared therefore quota charging is performed
1437 : * at a higher level.
1438 : */
1439 0 : dquot_free_inode(ea_inode);
1440 0 : dquot_drop(ea_inode);
1441 0 : inode_lock(ea_inode);
1442 0 : ea_inode->i_flags |= S_NOQUOTA;
1443 0 : inode_unlock(ea_inode);
1444 : }
1445 :
1446 : return ea_inode;
1447 : }
1448 :
1449 : static struct inode *
1450 0 : ext4_xattr_inode_cache_find(struct inode *inode, const void *value,
1451 : size_t value_len, u32 hash)
1452 : {
1453 0 : struct inode *ea_inode;
1454 0 : struct mb_cache_entry *ce;
1455 0 : struct mb_cache *ea_inode_cache = EA_INODE_CACHE(inode);
1456 0 : void *ea_data;
1457 :
1458 0 : if (!ea_inode_cache)
1459 : return NULL;
1460 :
1461 0 : ce = mb_cache_entry_find_first(ea_inode_cache, hash);
1462 0 : if (!ce)
1463 : return NULL;
1464 :
1465 0 : ea_data = kvmalloc(value_len, GFP_KERNEL);
1466 0 : if (!ea_data) {
1467 0 : mb_cache_entry_put(ea_inode_cache, ce);
1468 0 : return NULL;
1469 : }
1470 :
1471 0 : while (ce) {
1472 0 : ea_inode = ext4_iget(inode->i_sb, ce->e_value,
1473 : EXT4_IGET_NORMAL);
1474 0 : if (!IS_ERR(ea_inode) &&
1475 0 : !is_bad_inode(ea_inode) &&
1476 0 : (EXT4_I(ea_inode)->i_flags & EXT4_EA_INODE_FL) &&
1477 0 : i_size_read(ea_inode) == value_len &&
1478 0 : !ext4_xattr_inode_read(ea_inode, ea_data, value_len) &&
1479 0 : !ext4_xattr_inode_verify_hashes(ea_inode, NULL, ea_data,
1480 0 : value_len) &&
1481 0 : !memcmp(value, ea_data, value_len)) {
1482 0 : mb_cache_entry_touch(ea_inode_cache, ce);
1483 0 : mb_cache_entry_put(ea_inode_cache, ce);
1484 0 : kvfree(ea_data);
1485 0 : return ea_inode;
1486 : }
1487 :
1488 0 : if (!IS_ERR(ea_inode))
1489 0 : iput(ea_inode);
1490 0 : ce = mb_cache_entry_find_next(ea_inode_cache, ce);
1491 : }
1492 0 : kvfree(ea_data);
1493 0 : return NULL;
1494 : }
1495 :
1496 : /*
1497 : * Add value of the EA in an inode.
1498 : */
1499 0 : static int ext4_xattr_inode_lookup_create(handle_t *handle, struct inode *inode,
1500 : const void *value, size_t value_len,
1501 : struct inode **ret_inode)
1502 : {
1503 0 : struct inode *ea_inode;
1504 0 : u32 hash;
1505 0 : int err;
1506 :
1507 0 : hash = ext4_xattr_inode_hash(EXT4_SB(inode->i_sb), value, value_len);
1508 0 : ea_inode = ext4_xattr_inode_cache_find(inode, value, value_len, hash);
1509 0 : if (ea_inode) {
1510 0 : err = ext4_xattr_inode_inc_ref(handle, ea_inode);
1511 0 : if (err) {
1512 0 : iput(ea_inode);
1513 0 : return err;
1514 : }
1515 :
1516 0 : *ret_inode = ea_inode;
1517 0 : return 0;
1518 : }
1519 :
1520 : /* Create an inode for the EA value */
1521 0 : ea_inode = ext4_xattr_inode_create(handle, inode, hash);
1522 0 : if (IS_ERR(ea_inode))
1523 0 : return PTR_ERR(ea_inode);
1524 :
1525 0 : err = ext4_xattr_inode_write(handle, ea_inode, value, value_len);
1526 0 : if (err) {
1527 0 : ext4_xattr_inode_dec_ref(handle, ea_inode);
1528 0 : iput(ea_inode);
1529 0 : return err;
1530 : }
1531 :
1532 0 : if (EA_INODE_CACHE(inode))
1533 0 : mb_cache_entry_create(EA_INODE_CACHE(inode), GFP_NOFS, hash,
1534 0 : ea_inode->i_ino, true /* reusable */);
1535 :
1536 0 : *ret_inode = ea_inode;
1537 0 : return 0;
1538 : }
1539 :
1540 : /*
1541 : * Reserve min(block_size/8, 1024) bytes for xattr entries/names if ea_inode
1542 : * feature is enabled.
1543 : */
1544 : #define EXT4_XATTR_BLOCK_RESERVE(inode) min(i_blocksize(inode)/8, 1024U)
1545 :
1546 0 : static int ext4_xattr_set_entry(struct ext4_xattr_info *i,
1547 : struct ext4_xattr_search *s,
1548 : handle_t *handle, struct inode *inode,
1549 : bool is_block)
1550 : {
1551 0 : struct ext4_xattr_entry *last, *next;
1552 0 : struct ext4_xattr_entry *here = s->here;
1553 0 : size_t min_offs = s->end - s->base, name_len = strlen(i->name);
1554 0 : int in_inode = i->in_inode;
1555 0 : struct inode *old_ea_inode = NULL;
1556 0 : struct inode *new_ea_inode = NULL;
1557 0 : size_t old_size, new_size;
1558 0 : int ret;
1559 :
1560 : /* Space used by old and new values. */
1561 0 : old_size = (!s->not_found && !here->e_value_inum) ?
1562 0 : EXT4_XATTR_SIZE(le32_to_cpu(here->e_value_size)) : 0;
1563 0 : new_size = (i->value && !in_inode) ? EXT4_XATTR_SIZE(i->value_len) : 0;
1564 :
1565 : /*
1566 : * Optimization for the simple case when old and new values have the
1567 : * same padded sizes. Not applicable if external inodes are involved.
1568 : */
1569 0 : if (new_size && new_size == old_size) {
1570 0 : size_t offs = le16_to_cpu(here->e_value_offs);
1571 0 : void *val = s->base + offs;
1572 :
1573 0 : here->e_value_size = cpu_to_le32(i->value_len);
1574 0 : if (i->value == EXT4_ZERO_XATTR_VALUE) {
1575 0 : memset(val, 0, new_size);
1576 : } else {
1577 0 : memcpy(val, i->value, i->value_len);
1578 : /* Clear padding bytes. */
1579 0 : memset(val + i->value_len, 0, new_size - i->value_len);
1580 : }
1581 0 : goto update_hash;
1582 : }
1583 :
1584 : /* Compute min_offs and last. */
1585 0 : last = s->first;
1586 0 : for (; !IS_LAST_ENTRY(last); last = next) {
1587 0 : next = EXT4_XATTR_NEXT(last);
1588 0 : if ((void *)next >= s->end) {
1589 0 : EXT4_ERROR_INODE(inode, "corrupted xattr entries");
1590 0 : ret = -EFSCORRUPTED;
1591 0 : goto out;
1592 : }
1593 0 : if (!last->e_value_inum && last->e_value_size) {
1594 0 : size_t offs = le16_to_cpu(last->e_value_offs);
1595 0 : if (offs < min_offs)
1596 : min_offs = offs;
1597 : }
1598 : }
1599 :
1600 : /* Check whether we have enough space. */
1601 0 : if (i->value) {
1602 0 : size_t free;
1603 :
1604 0 : free = min_offs - ((void *)last - s->base) - sizeof(__u32);
1605 0 : if (!s->not_found)
1606 0 : free += EXT4_XATTR_LEN(name_len) + old_size;
1607 :
1608 0 : if (free < EXT4_XATTR_LEN(name_len) + new_size) {
1609 0 : ret = -ENOSPC;
1610 0 : goto out;
1611 : }
1612 :
1613 : /*
1614 : * If storing the value in an external inode is an option,
1615 : * reserve space for xattr entries/names in the external
1616 : * attribute block so that a long value does not occupy the
1617 : * whole space and prevent futher entries being added.
1618 : */
1619 0 : if (ext4_has_feature_ea_inode(inode->i_sb) &&
1620 0 : new_size && is_block &&
1621 0 : (min_offs + old_size - new_size) <
1622 0 : EXT4_XATTR_BLOCK_RESERVE(inode)) {
1623 0 : ret = -ENOSPC;
1624 0 : goto out;
1625 : }
1626 : }
1627 :
1628 : /*
1629 : * Getting access to old and new ea inodes is subject to failures.
1630 : * Finish that work before doing any modifications to the xattr data.
1631 : */
1632 0 : if (!s->not_found && here->e_value_inum) {
1633 0 : ret = ext4_xattr_inode_iget(inode,
1634 : le32_to_cpu(here->e_value_inum),
1635 0 : le32_to_cpu(here->e_hash),
1636 : &old_ea_inode);
1637 0 : if (ret) {
1638 0 : old_ea_inode = NULL;
1639 0 : goto out;
1640 : }
1641 : }
1642 0 : if (i->value && in_inode) {
1643 0 : WARN_ON_ONCE(!i->value_len);
1644 :
1645 0 : ret = ext4_xattr_inode_alloc_quota(inode, i->value_len);
1646 0 : if (ret)
1647 0 : goto out;
1648 :
1649 0 : ret = ext4_xattr_inode_lookup_create(handle, inode, i->value,
1650 : i->value_len,
1651 : &new_ea_inode);
1652 0 : if (ret) {
1653 0 : new_ea_inode = NULL;
1654 0 : ext4_xattr_inode_free_quota(inode, NULL, i->value_len);
1655 0 : goto out;
1656 : }
1657 : }
1658 :
1659 0 : if (old_ea_inode) {
1660 : /* We are ready to release ref count on the old_ea_inode. */
1661 0 : ret = ext4_xattr_inode_dec_ref(handle, old_ea_inode);
1662 0 : if (ret) {
1663 : /* Release newly required ref count on new_ea_inode. */
1664 0 : if (new_ea_inode) {
1665 0 : int err;
1666 :
1667 0 : err = ext4_xattr_inode_dec_ref(handle,
1668 : new_ea_inode);
1669 0 : if (err)
1670 0 : ext4_warning_inode(new_ea_inode,
1671 : "dec ref new_ea_inode err=%d",
1672 : err);
1673 0 : ext4_xattr_inode_free_quota(inode, new_ea_inode,
1674 : i->value_len);
1675 : }
1676 0 : goto out;
1677 : }
1678 :
1679 0 : ext4_xattr_inode_free_quota(inode, old_ea_inode,
1680 0 : le32_to_cpu(here->e_value_size));
1681 : }
1682 :
1683 : /* No failures allowed past this point. */
1684 :
1685 0 : if (!s->not_found && here->e_value_size && !here->e_value_inum) {
1686 : /* Remove the old value. */
1687 0 : void *first_val = s->base + min_offs;
1688 0 : size_t offs = le16_to_cpu(here->e_value_offs);
1689 0 : void *val = s->base + offs;
1690 :
1691 0 : memmove(first_val + old_size, first_val, val - first_val);
1692 0 : memset(first_val, 0, old_size);
1693 0 : min_offs += old_size;
1694 :
1695 : /* Adjust all value offsets. */
1696 0 : last = s->first;
1697 0 : while (!IS_LAST_ENTRY(last)) {
1698 0 : size_t o = le16_to_cpu(last->e_value_offs);
1699 :
1700 0 : if (!last->e_value_inum &&
1701 0 : last->e_value_size && o < offs)
1702 0 : last->e_value_offs = cpu_to_le16(o + old_size);
1703 0 : last = EXT4_XATTR_NEXT(last);
1704 : }
1705 : }
1706 :
1707 0 : if (!i->value) {
1708 : /* Remove old name. */
1709 0 : size_t size = EXT4_XATTR_LEN(name_len);
1710 :
1711 0 : last = ENTRY((void *)last - size);
1712 0 : memmove(here, (void *)here + size,
1713 0 : (void *)last - (void *)here + sizeof(__u32));
1714 0 : memset(last, 0, size);
1715 0 : } else if (s->not_found) {
1716 : /* Insert new name. */
1717 0 : size_t size = EXT4_XATTR_LEN(name_len);
1718 0 : size_t rest = (void *)last - (void *)here + sizeof(__u32);
1719 :
1720 0 : memmove((void *)here + size, here, rest);
1721 0 : memset(here, 0, size);
1722 0 : here->e_name_index = i->name_index;
1723 0 : here->e_name_len = name_len;
1724 0 : memcpy(here->e_name, i->name, name_len);
1725 : } else {
1726 : /* This is an update, reset value info. */
1727 0 : here->e_value_inum = 0;
1728 0 : here->e_value_offs = 0;
1729 0 : here->e_value_size = 0;
1730 : }
1731 :
1732 0 : if (i->value) {
1733 : /* Insert new value. */
1734 0 : if (in_inode) {
1735 0 : here->e_value_inum = cpu_to_le32(new_ea_inode->i_ino);
1736 0 : } else if (i->value_len) {
1737 0 : void *val = s->base + min_offs - new_size;
1738 :
1739 0 : here->e_value_offs = cpu_to_le16(min_offs - new_size);
1740 0 : if (i->value == EXT4_ZERO_XATTR_VALUE) {
1741 0 : memset(val, 0, new_size);
1742 : } else {
1743 0 : memcpy(val, i->value, i->value_len);
1744 : /* Clear padding bytes. */
1745 0 : memset(val + i->value_len, 0,
1746 0 : new_size - i->value_len);
1747 : }
1748 : }
1749 0 : here->e_value_size = cpu_to_le32(i->value_len);
1750 : }
1751 :
1752 0 : update_hash:
1753 0 : if (i->value) {
1754 0 : __le32 hash = 0;
1755 :
1756 : /* Entry hash calculation. */
1757 0 : if (in_inode) {
1758 0 : __le32 crc32c_hash;
1759 :
1760 : /*
1761 : * Feed crc32c hash instead of the raw value for entry
1762 : * hash calculation. This is to avoid walking
1763 : * potentially long value buffer again.
1764 : */
1765 0 : crc32c_hash = cpu_to_le32(
1766 : ext4_xattr_inode_get_hash(new_ea_inode));
1767 0 : hash = ext4_xattr_hash_entry(here->e_name,
1768 0 : here->e_name_len,
1769 : &crc32c_hash, 1);
1770 0 : } else if (is_block) {
1771 0 : __le32 *value = s->base + le16_to_cpu(
1772 : here->e_value_offs);
1773 :
1774 0 : hash = ext4_xattr_hash_entry(here->e_name,
1775 0 : here->e_name_len, value,
1776 : new_size >> 2);
1777 : }
1778 0 : here->e_hash = hash;
1779 : }
1780 :
1781 0 : if (is_block)
1782 0 : ext4_xattr_rehash((struct ext4_xattr_header *)s->base);
1783 :
1784 : ret = 0;
1785 0 : out:
1786 0 : iput(old_ea_inode);
1787 0 : iput(new_ea_inode);
1788 0 : return ret;
1789 : }
1790 :
1791 : struct ext4_xattr_block_find {
1792 : struct ext4_xattr_search s;
1793 : struct buffer_head *bh;
1794 : };
1795 :
1796 : static int
1797 0 : ext4_xattr_block_find(struct inode *inode, struct ext4_xattr_info *i,
1798 : struct ext4_xattr_block_find *bs)
1799 : {
1800 0 : struct super_block *sb = inode->i_sb;
1801 0 : int error;
1802 :
1803 0 : ea_idebug(inode, "name=%d.%s, value=%p, value_len=%ld",
1804 : i->name_index, i->name, i->value, (long)i->value_len);
1805 :
1806 0 : if (EXT4_I(inode)->i_file_acl) {
1807 : /* The inode already has an extended attribute block. */
1808 0 : bs->bh = ext4_sb_bread(sb, EXT4_I(inode)->i_file_acl, REQ_PRIO);
1809 0 : if (IS_ERR(bs->bh)) {
1810 0 : error = PTR_ERR(bs->bh);
1811 0 : bs->bh = NULL;
1812 0 : return error;
1813 : }
1814 0 : ea_bdebug(bs->bh, "b_count=%d, refcount=%d",
1815 : atomic_read(&(bs->bh->b_count)),
1816 : le32_to_cpu(BHDR(bs->bh)->h_refcount));
1817 0 : error = ext4_xattr_check_block(inode, bs->bh);
1818 0 : if (error)
1819 : return error;
1820 : /* Find the named attribute. */
1821 0 : bs->s.base = BHDR(bs->bh);
1822 0 : bs->s.first = BFIRST(bs->bh);
1823 0 : bs->s.end = bs->bh->b_data + bs->bh->b_size;
1824 0 : bs->s.here = bs->s.first;
1825 0 : error = xattr_find_entry(inode, &bs->s.here, bs->s.end,
1826 : i->name_index, i->name, 1);
1827 0 : if (error && error != -ENODATA)
1828 : return error;
1829 0 : bs->s.not_found = error;
1830 : }
1831 : return 0;
1832 : }
1833 :
1834 : static int
1835 0 : ext4_xattr_block_set(handle_t *handle, struct inode *inode,
1836 : struct ext4_xattr_info *i,
1837 : struct ext4_xattr_block_find *bs)
1838 : {
1839 0 : struct super_block *sb = inode->i_sb;
1840 0 : struct buffer_head *new_bh = NULL;
1841 0 : struct ext4_xattr_search s_copy = bs->s;
1842 0 : struct ext4_xattr_search *s = &s_copy;
1843 0 : struct mb_cache_entry *ce = NULL;
1844 0 : int error = 0;
1845 0 : struct mb_cache *ea_block_cache = EA_BLOCK_CACHE(inode);
1846 0 : struct inode *ea_inode = NULL, *tmp_inode;
1847 0 : size_t old_ea_inode_quota = 0;
1848 0 : unsigned int ea_ino;
1849 :
1850 :
1851 : #define header(x) ((struct ext4_xattr_header *)(x))
1852 :
1853 0 : if (s->base) {
1854 0 : BUFFER_TRACE(bs->bh, "get_write_access");
1855 0 : error = ext4_journal_get_write_access(handle, bs->bh);
1856 0 : if (error)
1857 0 : goto cleanup;
1858 0 : lock_buffer(bs->bh);
1859 :
1860 0 : if (header(s->base)->h_refcount == cpu_to_le32(1)) {
1861 0 : __u32 hash = le32_to_cpu(BHDR(bs->bh)->h_hash);
1862 :
1863 : /*
1864 : * This must happen under buffer lock for
1865 : * ext4_xattr_block_set() to reliably detect modified
1866 : * block
1867 : */
1868 0 : if (ea_block_cache)
1869 0 : mb_cache_entry_delete(ea_block_cache, hash,
1870 : bs->bh->b_blocknr);
1871 0 : ea_bdebug(bs->bh, "modifying in-place");
1872 0 : error = ext4_xattr_set_entry(i, s, handle, inode,
1873 : true /* is_block */);
1874 0 : ext4_xattr_block_csum_set(inode, bs->bh);
1875 0 : unlock_buffer(bs->bh);
1876 0 : if (error == -EFSCORRUPTED)
1877 0 : goto bad_block;
1878 0 : if (!error)
1879 0 : error = ext4_handle_dirty_metadata(handle,
1880 : inode,
1881 : bs->bh);
1882 0 : if (error)
1883 0 : goto cleanup;
1884 0 : goto inserted;
1885 : } else {
1886 0 : int offset = (char *)s->here - bs->bh->b_data;
1887 :
1888 0 : unlock_buffer(bs->bh);
1889 0 : ea_bdebug(bs->bh, "cloning");
1890 0 : s->base = kmalloc(bs->bh->b_size, GFP_NOFS);
1891 0 : error = -ENOMEM;
1892 0 : if (s->base == NULL)
1893 0 : goto cleanup;
1894 0 : memcpy(s->base, BHDR(bs->bh), bs->bh->b_size);
1895 0 : s->first = ENTRY(header(s->base)+1);
1896 0 : header(s->base)->h_refcount = cpu_to_le32(1);
1897 0 : s->here = ENTRY(s->base + offset);
1898 0 : s->end = s->base + bs->bh->b_size;
1899 :
1900 : /*
1901 : * If existing entry points to an xattr inode, we need
1902 : * to prevent ext4_xattr_set_entry() from decrementing
1903 : * ref count on it because the reference belongs to the
1904 : * original block. In this case, make the entry look
1905 : * like it has an empty value.
1906 : */
1907 0 : if (!s->not_found && s->here->e_value_inum) {
1908 0 : ea_ino = le32_to_cpu(s->here->e_value_inum);
1909 0 : error = ext4_xattr_inode_iget(inode, ea_ino,
1910 0 : le32_to_cpu(s->here->e_hash),
1911 : &tmp_inode);
1912 0 : if (error)
1913 0 : goto cleanup;
1914 :
1915 0 : if (!ext4_test_inode_state(tmp_inode,
1916 : EXT4_STATE_LUSTRE_EA_INODE)) {
1917 : /*
1918 : * Defer quota free call for previous
1919 : * inode until success is guaranteed.
1920 : */
1921 0 : old_ea_inode_quota = le32_to_cpu(
1922 : s->here->e_value_size);
1923 : }
1924 0 : iput(tmp_inode);
1925 :
1926 0 : s->here->e_value_inum = 0;
1927 0 : s->here->e_value_size = 0;
1928 : }
1929 : }
1930 : } else {
1931 : /* Allocate a buffer where we construct the new block. */
1932 0 : s->base = kzalloc(sb->s_blocksize, GFP_NOFS);
1933 0 : error = -ENOMEM;
1934 0 : if (s->base == NULL)
1935 0 : goto cleanup;
1936 0 : header(s->base)->h_magic = cpu_to_le32(EXT4_XATTR_MAGIC);
1937 0 : header(s->base)->h_blocks = cpu_to_le32(1);
1938 0 : header(s->base)->h_refcount = cpu_to_le32(1);
1939 0 : s->first = ENTRY(header(s->base)+1);
1940 0 : s->here = ENTRY(header(s->base)+1);
1941 0 : s->end = s->base + sb->s_blocksize;
1942 : }
1943 :
1944 0 : error = ext4_xattr_set_entry(i, s, handle, inode, true /* is_block */);
1945 0 : if (error == -EFSCORRUPTED)
1946 0 : goto bad_block;
1947 0 : if (error)
1948 0 : goto cleanup;
1949 :
1950 0 : if (i->value && s->here->e_value_inum) {
1951 : /*
1952 : * A ref count on ea_inode has been taken as part of the call to
1953 : * ext4_xattr_set_entry() above. We would like to drop this
1954 : * extra ref but we have to wait until the xattr block is
1955 : * initialized and has its own ref count on the ea_inode.
1956 : */
1957 0 : ea_ino = le32_to_cpu(s->here->e_value_inum);
1958 0 : error = ext4_xattr_inode_iget(inode, ea_ino,
1959 0 : le32_to_cpu(s->here->e_hash),
1960 : &ea_inode);
1961 0 : if (error) {
1962 0 : ea_inode = NULL;
1963 0 : goto cleanup;
1964 : }
1965 : }
1966 :
1967 0 : inserted:
1968 0 : if (!IS_LAST_ENTRY(s->first)) {
1969 0 : new_bh = ext4_xattr_block_cache_find(inode, header(s->base),
1970 : &ce);
1971 0 : if (new_bh) {
1972 : /* We found an identical block in the cache. */
1973 0 : if (new_bh == bs->bh)
1974 : ea_bdebug(new_bh, "keeping");
1975 : else {
1976 0 : u32 ref;
1977 :
1978 0 : WARN_ON_ONCE(dquot_initialize_needed(inode));
1979 :
1980 : /* The old block is released after updating
1981 : the inode. */
1982 0 : error = dquot_alloc_block(inode,
1983 0 : EXT4_C2B(EXT4_SB(sb), 1));
1984 0 : if (error)
1985 0 : goto cleanup;
1986 0 : BUFFER_TRACE(new_bh, "get_write_access");
1987 0 : error = ext4_journal_get_write_access(handle,
1988 : new_bh);
1989 0 : if (error)
1990 0 : goto cleanup_dquot;
1991 0 : lock_buffer(new_bh);
1992 : /*
1993 : * We have to be careful about races with
1994 : * freeing, rehashing or adding references to
1995 : * xattr block. Once we hold buffer lock xattr
1996 : * block's state is stable so we can check
1997 : * whether the block got freed / rehashed or
1998 : * not. Since we unhash mbcache entry under
1999 : * buffer lock when freeing / rehashing xattr
2000 : * block, checking whether entry is still
2001 : * hashed is reliable. Same rules hold for
2002 : * e_reusable handling.
2003 : */
2004 0 : if (hlist_bl_unhashed(&ce->e_hash_list) ||
2005 0 : !ce->e_reusable) {
2006 : /*
2007 : * Undo everything and check mbcache
2008 : * again.
2009 : */
2010 0 : unlock_buffer(new_bh);
2011 0 : dquot_free_block(inode,
2012 0 : EXT4_C2B(EXT4_SB(sb),
2013 : 1));
2014 0 : brelse(new_bh);
2015 0 : mb_cache_entry_put(ea_block_cache, ce);
2016 0 : ce = NULL;
2017 0 : new_bh = NULL;
2018 0 : goto inserted;
2019 : }
2020 0 : ref = le32_to_cpu(BHDR(new_bh)->h_refcount) + 1;
2021 0 : BHDR(new_bh)->h_refcount = cpu_to_le32(ref);
2022 0 : if (ref >= EXT4_XATTR_REFCOUNT_MAX)
2023 0 : ce->e_reusable = 0;
2024 0 : ea_bdebug(new_bh, "reusing; refcount now=%d",
2025 : ref);
2026 0 : ext4_xattr_block_csum_set(inode, new_bh);
2027 0 : unlock_buffer(new_bh);
2028 0 : error = ext4_handle_dirty_metadata(handle,
2029 : inode,
2030 : new_bh);
2031 0 : if (error)
2032 0 : goto cleanup_dquot;
2033 : }
2034 0 : mb_cache_entry_touch(ea_block_cache, ce);
2035 0 : mb_cache_entry_put(ea_block_cache, ce);
2036 0 : ce = NULL;
2037 0 : } else if (bs->bh && s->base == bs->bh->b_data) {
2038 : /* We were modifying this block in-place. */
2039 0 : ea_bdebug(bs->bh, "keeping this block");
2040 0 : ext4_xattr_block_cache_insert(ea_block_cache, bs->bh);
2041 0 : new_bh = bs->bh;
2042 0 : get_bh(new_bh);
2043 : } else {
2044 : /* We need to allocate a new block */
2045 0 : ext4_fsblk_t goal, block;
2046 :
2047 0 : WARN_ON_ONCE(dquot_initialize_needed(inode));
2048 :
2049 0 : goal = ext4_group_first_block_no(sb,
2050 0 : EXT4_I(inode)->i_block_group);
2051 :
2052 : /* non-extent files can't have physical blocks past 2^32 */
2053 0 : if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
2054 0 : goal = goal & EXT4_MAX_BLOCK_FILE_PHYS;
2055 :
2056 0 : block = ext4_new_meta_blocks(handle, inode, goal, 0,
2057 : NULL, &error);
2058 0 : if (error)
2059 0 : goto cleanup;
2060 :
2061 0 : if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
2062 0 : BUG_ON(block > EXT4_MAX_BLOCK_FILE_PHYS);
2063 :
2064 0 : ea_idebug(inode, "creating block %llu",
2065 : (unsigned long long)block);
2066 :
2067 0 : new_bh = sb_getblk(sb, block);
2068 0 : if (unlikely(!new_bh)) {
2069 0 : error = -ENOMEM;
2070 0 : getblk_failed:
2071 0 : ext4_free_blocks(handle, inode, NULL, block, 1,
2072 : EXT4_FREE_BLOCKS_METADATA);
2073 0 : goto cleanup;
2074 : }
2075 0 : error = ext4_xattr_inode_inc_ref_all(handle, inode,
2076 0 : ENTRY(header(s->base)+1));
2077 0 : if (error)
2078 0 : goto getblk_failed;
2079 0 : if (ea_inode) {
2080 : /* Drop the extra ref on ea_inode. */
2081 0 : error = ext4_xattr_inode_dec_ref(handle,
2082 : ea_inode);
2083 0 : if (error)
2084 0 : ext4_warning_inode(ea_inode,
2085 : "dec ref error=%d",
2086 : error);
2087 0 : iput(ea_inode);
2088 0 : ea_inode = NULL;
2089 : }
2090 :
2091 0 : lock_buffer(new_bh);
2092 0 : error = ext4_journal_get_create_access(handle, new_bh);
2093 0 : if (error) {
2094 0 : unlock_buffer(new_bh);
2095 0 : error = -EIO;
2096 0 : goto getblk_failed;
2097 : }
2098 0 : memcpy(new_bh->b_data, s->base, new_bh->b_size);
2099 0 : ext4_xattr_block_csum_set(inode, new_bh);
2100 0 : set_buffer_uptodate(new_bh);
2101 0 : unlock_buffer(new_bh);
2102 0 : ext4_xattr_block_cache_insert(ea_block_cache, new_bh);
2103 0 : error = ext4_handle_dirty_metadata(handle, inode,
2104 : new_bh);
2105 0 : if (error)
2106 0 : goto cleanup;
2107 : }
2108 : }
2109 :
2110 0 : if (old_ea_inode_quota)
2111 0 : ext4_xattr_inode_free_quota(inode, NULL, old_ea_inode_quota);
2112 :
2113 : /* Update the inode. */
2114 0 : EXT4_I(inode)->i_file_acl = new_bh ? new_bh->b_blocknr : 0;
2115 :
2116 : /* Drop the previous xattr block. */
2117 0 : if (bs->bh && bs->bh != new_bh) {
2118 0 : struct ext4_xattr_inode_array *ea_inode_array = NULL;
2119 :
2120 0 : ext4_xattr_release_block(handle, inode, bs->bh,
2121 : &ea_inode_array,
2122 : 0 /* extra_credits */);
2123 0 : ext4_xattr_inode_array_free(ea_inode_array);
2124 : }
2125 0 : error = 0;
2126 :
2127 0 : cleanup:
2128 0 : if (ea_inode) {
2129 0 : int error2;
2130 :
2131 0 : error2 = ext4_xattr_inode_dec_ref(handle, ea_inode);
2132 0 : if (error2)
2133 0 : ext4_warning_inode(ea_inode, "dec ref error=%d",
2134 : error2);
2135 :
2136 : /* If there was an error, revert the quota charge. */
2137 0 : if (error)
2138 0 : ext4_xattr_inode_free_quota(inode, ea_inode,
2139 0 : i_size_read(ea_inode));
2140 0 : iput(ea_inode);
2141 : }
2142 0 : if (ce)
2143 0 : mb_cache_entry_put(ea_block_cache, ce);
2144 0 : brelse(new_bh);
2145 0 : if (!(bs->bh && s->base == bs->bh->b_data))
2146 0 : kfree(s->base);
2147 :
2148 0 : return error;
2149 :
2150 0 : cleanup_dquot:
2151 0 : dquot_free_block(inode, EXT4_C2B(EXT4_SB(sb), 1));
2152 0 : goto cleanup;
2153 :
2154 0 : bad_block:
2155 0 : EXT4_ERROR_INODE(inode, "bad block %llu",
2156 : EXT4_I(inode)->i_file_acl);
2157 0 : goto cleanup;
2158 :
2159 : #undef header
2160 : }
2161 :
2162 0 : int ext4_xattr_ibody_find(struct inode *inode, struct ext4_xattr_info *i,
2163 : struct ext4_xattr_ibody_find *is)
2164 : {
2165 0 : struct ext4_xattr_ibody_header *header;
2166 0 : struct ext4_inode *raw_inode;
2167 0 : int error;
2168 :
2169 0 : if (EXT4_I(inode)->i_extra_isize == 0)
2170 : return 0;
2171 0 : raw_inode = ext4_raw_inode(&is->iloc);
2172 0 : header = IHDR(inode, raw_inode);
2173 0 : is->s.base = is->s.first = IFIRST(header);
2174 0 : is->s.here = is->s.first;
2175 0 : is->s.end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size;
2176 0 : if (ext4_test_inode_state(inode, EXT4_STATE_XATTR)) {
2177 0 : error = xattr_check_inode(inode, header, is->s.end);
2178 0 : if (error)
2179 : return error;
2180 : /* Find the named attribute. */
2181 0 : error = xattr_find_entry(inode, &is->s.here, is->s.end,
2182 : i->name_index, i->name, 0);
2183 0 : if (error && error != -ENODATA)
2184 : return error;
2185 0 : is->s.not_found = error;
2186 : }
2187 : return 0;
2188 : }
2189 :
2190 0 : int ext4_xattr_ibody_inline_set(handle_t *handle, struct inode *inode,
2191 : struct ext4_xattr_info *i,
2192 : struct ext4_xattr_ibody_find *is)
2193 : {
2194 0 : struct ext4_xattr_ibody_header *header;
2195 0 : struct ext4_xattr_search *s = &is->s;
2196 0 : int error;
2197 :
2198 0 : if (EXT4_I(inode)->i_extra_isize == 0)
2199 : return -ENOSPC;
2200 0 : error = ext4_xattr_set_entry(i, s, handle, inode, false /* is_block */);
2201 0 : if (error)
2202 : return error;
2203 0 : header = IHDR(inode, ext4_raw_inode(&is->iloc));
2204 0 : if (!IS_LAST_ENTRY(s->first)) {
2205 0 : header->h_magic = cpu_to_le32(EXT4_XATTR_MAGIC);
2206 0 : ext4_set_inode_state(inode, EXT4_STATE_XATTR);
2207 : } else {
2208 0 : header->h_magic = cpu_to_le32(0);
2209 0 : ext4_clear_inode_state(inode, EXT4_STATE_XATTR);
2210 : }
2211 : return 0;
2212 : }
2213 :
2214 0 : static int ext4_xattr_ibody_set(handle_t *handle, struct inode *inode,
2215 : struct ext4_xattr_info *i,
2216 : struct ext4_xattr_ibody_find *is)
2217 : {
2218 0 : struct ext4_xattr_ibody_header *header;
2219 0 : struct ext4_xattr_search *s = &is->s;
2220 0 : int error;
2221 :
2222 0 : if (EXT4_I(inode)->i_extra_isize == 0)
2223 : return -ENOSPC;
2224 0 : error = ext4_xattr_set_entry(i, s, handle, inode, false /* is_block */);
2225 0 : if (error)
2226 : return error;
2227 0 : header = IHDR(inode, ext4_raw_inode(&is->iloc));
2228 0 : if (!IS_LAST_ENTRY(s->first)) {
2229 0 : header->h_magic = cpu_to_le32(EXT4_XATTR_MAGIC);
2230 0 : ext4_set_inode_state(inode, EXT4_STATE_XATTR);
2231 : } else {
2232 0 : header->h_magic = cpu_to_le32(0);
2233 0 : ext4_clear_inode_state(inode, EXT4_STATE_XATTR);
2234 : }
2235 : return 0;
2236 : }
2237 :
2238 0 : static int ext4_xattr_value_same(struct ext4_xattr_search *s,
2239 : struct ext4_xattr_info *i)
2240 : {
2241 0 : void *value;
2242 :
2243 : /* When e_value_inum is set the value is stored externally. */
2244 0 : if (s->here->e_value_inum)
2245 : return 0;
2246 0 : if (le32_to_cpu(s->here->e_value_size) != i->value_len)
2247 : return 0;
2248 0 : value = ((void *)s->base) + le16_to_cpu(s->here->e_value_offs);
2249 0 : return !memcmp(value, i->value, i->value_len);
2250 : }
2251 :
2252 0 : static struct buffer_head *ext4_xattr_get_block(struct inode *inode)
2253 : {
2254 0 : struct buffer_head *bh;
2255 0 : int error;
2256 :
2257 0 : if (!EXT4_I(inode)->i_file_acl)
2258 : return NULL;
2259 0 : bh = ext4_sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl, REQ_PRIO);
2260 0 : if (IS_ERR(bh))
2261 : return bh;
2262 0 : error = ext4_xattr_check_block(inode, bh);
2263 0 : if (error) {
2264 0 : brelse(bh);
2265 0 : return ERR_PTR(error);
2266 : }
2267 : return bh;
2268 : }
2269 :
2270 : /*
2271 : * ext4_xattr_set_handle()
2272 : *
2273 : * Create, replace or remove an extended attribute for this inode. Value
2274 : * is NULL to remove an existing extended attribute, and non-NULL to
2275 : * either replace an existing extended attribute, or create a new extended
2276 : * attribute. The flags XATTR_REPLACE and XATTR_CREATE
2277 : * specify that an extended attribute must exist and must not exist
2278 : * previous to the call, respectively.
2279 : *
2280 : * Returns 0, or a negative error number on failure.
2281 : */
2282 : int
2283 0 : ext4_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index,
2284 : const char *name, const void *value, size_t value_len,
2285 : int flags)
2286 : {
2287 0 : struct ext4_xattr_info i = {
2288 : .name_index = name_index,
2289 : .name = name,
2290 : .value = value,
2291 : .value_len = value_len,
2292 : .in_inode = 0,
2293 : };
2294 0 : struct ext4_xattr_ibody_find is = {
2295 : .s = { .not_found = -ENODATA, },
2296 : };
2297 0 : struct ext4_xattr_block_find bs = {
2298 : .s = { .not_found = -ENODATA, },
2299 : };
2300 0 : int no_expand;
2301 0 : int error;
2302 :
2303 0 : if (!name)
2304 : return -EINVAL;
2305 0 : if (strlen(name) > 255)
2306 : return -ERANGE;
2307 :
2308 0 : ext4_write_lock_xattr(inode, &no_expand);
2309 :
2310 : /* Check journal credits under write lock. */
2311 0 : if (ext4_handle_valid(handle)) {
2312 0 : struct buffer_head *bh;
2313 0 : int credits;
2314 :
2315 0 : bh = ext4_xattr_get_block(inode);
2316 0 : if (IS_ERR(bh)) {
2317 0 : error = PTR_ERR(bh);
2318 0 : goto cleanup;
2319 : }
2320 :
2321 0 : credits = __ext4_xattr_set_credits(inode->i_sb, inode, bh,
2322 : value_len,
2323 : flags & XATTR_CREATE);
2324 0 : brelse(bh);
2325 :
2326 0 : if (jbd2_handle_buffer_credits(handle) < credits) {
2327 0 : error = -ENOSPC;
2328 0 : goto cleanup;
2329 : }
2330 : }
2331 :
2332 0 : error = ext4_reserve_inode_write(handle, inode, &is.iloc);
2333 0 : if (error)
2334 0 : goto cleanup;
2335 :
2336 0 : if (ext4_test_inode_state(inode, EXT4_STATE_NEW)) {
2337 0 : struct ext4_inode *raw_inode = ext4_raw_inode(&is.iloc);
2338 0 : memset(raw_inode, 0, EXT4_SB(inode->i_sb)->s_inode_size);
2339 0 : ext4_clear_inode_state(inode, EXT4_STATE_NEW);
2340 : }
2341 :
2342 0 : error = ext4_xattr_ibody_find(inode, &i, &is);
2343 0 : if (error)
2344 0 : goto cleanup;
2345 0 : if (is.s.not_found)
2346 0 : error = ext4_xattr_block_find(inode, &i, &bs);
2347 0 : if (error)
2348 0 : goto cleanup;
2349 0 : if (is.s.not_found && bs.s.not_found) {
2350 0 : error = -ENODATA;
2351 0 : if (flags & XATTR_REPLACE)
2352 0 : goto cleanup;
2353 0 : error = 0;
2354 0 : if (!value)
2355 0 : goto cleanup;
2356 : } else {
2357 0 : error = -EEXIST;
2358 0 : if (flags & XATTR_CREATE)
2359 0 : goto cleanup;
2360 : }
2361 :
2362 0 : if (!value) {
2363 0 : if (!is.s.not_found)
2364 0 : error = ext4_xattr_ibody_set(handle, inode, &i, &is);
2365 0 : else if (!bs.s.not_found)
2366 0 : error = ext4_xattr_block_set(handle, inode, &i, &bs);
2367 : } else {
2368 0 : error = 0;
2369 : /* Xattr value did not change? Save us some work and bail out */
2370 0 : if (!is.s.not_found && ext4_xattr_value_same(&is.s, &i))
2371 0 : goto cleanup;
2372 0 : if (!bs.s.not_found && ext4_xattr_value_same(&bs.s, &i))
2373 0 : goto cleanup;
2374 :
2375 0 : if (ext4_has_feature_ea_inode(inode->i_sb) &&
2376 0 : (EXT4_XATTR_SIZE(i.value_len) >
2377 0 : EXT4_XATTR_MIN_LARGE_EA_SIZE(inode->i_sb->s_blocksize)))
2378 0 : i.in_inode = 1;
2379 0 : retry_inode:
2380 0 : error = ext4_xattr_ibody_set(handle, inode, &i, &is);
2381 0 : if (!error && !bs.s.not_found) {
2382 0 : i.value = NULL;
2383 0 : error = ext4_xattr_block_set(handle, inode, &i, &bs);
2384 0 : } else if (error == -ENOSPC) {
2385 0 : if (EXT4_I(inode)->i_file_acl && !bs.s.base) {
2386 0 : brelse(bs.bh);
2387 0 : bs.bh = NULL;
2388 0 : error = ext4_xattr_block_find(inode, &i, &bs);
2389 0 : if (error)
2390 0 : goto cleanup;
2391 : }
2392 0 : error = ext4_xattr_block_set(handle, inode, &i, &bs);
2393 0 : if (!error && !is.s.not_found) {
2394 0 : i.value = NULL;
2395 0 : error = ext4_xattr_ibody_set(handle, inode, &i,
2396 : &is);
2397 0 : } else if (error == -ENOSPC) {
2398 : /*
2399 : * Xattr does not fit in the block, store at
2400 : * external inode if possible.
2401 : */
2402 0 : if (ext4_has_feature_ea_inode(inode->i_sb) &&
2403 0 : !i.in_inode) {
2404 0 : i.in_inode = 1;
2405 0 : goto retry_inode;
2406 : }
2407 : }
2408 : }
2409 : }
2410 0 : if (!error) {
2411 0 : ext4_xattr_update_super_block(handle, inode->i_sb);
2412 0 : inode->i_ctime = current_time(inode);
2413 0 : if (!value)
2414 0 : no_expand = 0;
2415 0 : error = ext4_mark_iloc_dirty(handle, inode, &is.iloc);
2416 : /*
2417 : * The bh is consumed by ext4_mark_iloc_dirty, even with
2418 : * error != 0.
2419 : */
2420 0 : is.iloc.bh = NULL;
2421 0 : if (IS_SYNC(inode))
2422 0 : ext4_handle_sync(handle);
2423 : }
2424 0 : ext4_fc_mark_ineligible(inode->i_sb, EXT4_FC_REASON_XATTR);
2425 :
2426 0 : cleanup:
2427 0 : brelse(is.iloc.bh);
2428 0 : brelse(bs.bh);
2429 0 : ext4_write_unlock_xattr(inode, &no_expand);
2430 0 : return error;
2431 : }
2432 :
2433 0 : int ext4_xattr_set_credits(struct inode *inode, size_t value_len,
2434 : bool is_create, int *credits)
2435 : {
2436 0 : struct buffer_head *bh;
2437 0 : int err;
2438 :
2439 0 : *credits = 0;
2440 :
2441 0 : if (!EXT4_SB(inode->i_sb)->s_journal)
2442 : return 0;
2443 :
2444 0 : down_read(&EXT4_I(inode)->xattr_sem);
2445 :
2446 0 : bh = ext4_xattr_get_block(inode);
2447 0 : if (IS_ERR(bh)) {
2448 0 : err = PTR_ERR(bh);
2449 : } else {
2450 0 : *credits = __ext4_xattr_set_credits(inode->i_sb, inode, bh,
2451 : value_len, is_create);
2452 0 : brelse(bh);
2453 : err = 0;
2454 : }
2455 :
2456 0 : up_read(&EXT4_I(inode)->xattr_sem);
2457 0 : return err;
2458 : }
2459 :
2460 : /*
2461 : * ext4_xattr_set()
2462 : *
2463 : * Like ext4_xattr_set_handle, but start from an inode. This extended
2464 : * attribute modification is a filesystem transaction by itself.
2465 : *
2466 : * Returns 0, or a negative error number on failure.
2467 : */
2468 : int
2469 0 : ext4_xattr_set(struct inode *inode, int name_index, const char *name,
2470 : const void *value, size_t value_len, int flags)
2471 : {
2472 0 : handle_t *handle;
2473 0 : struct super_block *sb = inode->i_sb;
2474 0 : int error, retries = 0;
2475 0 : int credits;
2476 :
2477 0 : error = dquot_initialize(inode);
2478 0 : if (error)
2479 : return error;
2480 :
2481 0 : retry:
2482 0 : error = ext4_xattr_set_credits(inode, value_len, flags & XATTR_CREATE,
2483 : &credits);
2484 0 : if (error)
2485 0 : return error;
2486 :
2487 0 : handle = ext4_journal_start(inode, EXT4_HT_XATTR, credits);
2488 0 : if (IS_ERR(handle)) {
2489 0 : error = PTR_ERR(handle);
2490 : } else {
2491 0 : int error2;
2492 :
2493 0 : error = ext4_xattr_set_handle(handle, inode, name_index, name,
2494 : value, value_len, flags);
2495 0 : error2 = ext4_journal_stop(handle);
2496 0 : if (error == -ENOSPC &&
2497 0 : ext4_should_retry_alloc(sb, &retries))
2498 0 : goto retry;
2499 0 : if (error == 0)
2500 0 : error = error2;
2501 : }
2502 0 : ext4_fc_mark_ineligible(inode->i_sb, EXT4_FC_REASON_XATTR);
2503 :
2504 0 : return error;
2505 : }
2506 :
2507 : /*
2508 : * Shift the EA entries in the inode to create space for the increased
2509 : * i_extra_isize.
2510 : */
2511 0 : static void ext4_xattr_shift_entries(struct ext4_xattr_entry *entry,
2512 : int value_offs_shift, void *to,
2513 : void *from, size_t n)
2514 : {
2515 0 : struct ext4_xattr_entry *last = entry;
2516 0 : int new_offs;
2517 :
2518 : /* We always shift xattr headers further thus offsets get lower */
2519 0 : BUG_ON(value_offs_shift > 0);
2520 :
2521 : /* Adjust the value offsets of the entries */
2522 0 : for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) {
2523 0 : if (!last->e_value_inum && last->e_value_size) {
2524 0 : new_offs = le16_to_cpu(last->e_value_offs) +
2525 : value_offs_shift;
2526 0 : last->e_value_offs = cpu_to_le16(new_offs);
2527 : }
2528 : }
2529 : /* Shift the entries by n bytes */
2530 0 : memmove(to, from, n);
2531 0 : }
2532 :
2533 : /*
2534 : * Move xattr pointed to by 'entry' from inode into external xattr block
2535 : */
2536 0 : static int ext4_xattr_move_to_block(handle_t *handle, struct inode *inode,
2537 : struct ext4_inode *raw_inode,
2538 : struct ext4_xattr_entry *entry)
2539 : {
2540 0 : struct ext4_xattr_ibody_find *is = NULL;
2541 0 : struct ext4_xattr_block_find *bs = NULL;
2542 0 : char *buffer = NULL, *b_entry_name = NULL;
2543 0 : size_t value_size = le32_to_cpu(entry->e_value_size);
2544 0 : struct ext4_xattr_info i = {
2545 : .value = NULL,
2546 : .value_len = 0,
2547 0 : .name_index = entry->e_name_index,
2548 0 : .in_inode = !!entry->e_value_inum,
2549 : };
2550 0 : struct ext4_xattr_ibody_header *header = IHDR(inode, raw_inode);
2551 0 : int error;
2552 :
2553 0 : is = kzalloc(sizeof(struct ext4_xattr_ibody_find), GFP_NOFS);
2554 0 : bs = kzalloc(sizeof(struct ext4_xattr_block_find), GFP_NOFS);
2555 0 : buffer = kmalloc(value_size, GFP_NOFS);
2556 0 : b_entry_name = kmalloc(entry->e_name_len + 1, GFP_NOFS);
2557 0 : if (!is || !bs || !buffer || !b_entry_name) {
2558 0 : error = -ENOMEM;
2559 0 : goto out;
2560 : }
2561 :
2562 0 : is->s.not_found = -ENODATA;
2563 0 : bs->s.not_found = -ENODATA;
2564 0 : is->iloc.bh = NULL;
2565 0 : bs->bh = NULL;
2566 :
2567 : /* Save the entry name and the entry value */
2568 0 : if (entry->e_value_inum) {
2569 0 : error = ext4_xattr_inode_get(inode, entry, buffer, value_size);
2570 0 : if (error)
2571 0 : goto out;
2572 : } else {
2573 0 : size_t value_offs = le16_to_cpu(entry->e_value_offs);
2574 0 : memcpy(buffer, (void *)IFIRST(header) + value_offs, value_size);
2575 : }
2576 :
2577 0 : memcpy(b_entry_name, entry->e_name, entry->e_name_len);
2578 0 : b_entry_name[entry->e_name_len] = '\0';
2579 0 : i.name = b_entry_name;
2580 :
2581 0 : error = ext4_get_inode_loc(inode, &is->iloc);
2582 0 : if (error)
2583 0 : goto out;
2584 :
2585 0 : error = ext4_xattr_ibody_find(inode, &i, is);
2586 0 : if (error)
2587 0 : goto out;
2588 :
2589 : /* Remove the chosen entry from the inode */
2590 0 : error = ext4_xattr_ibody_set(handle, inode, &i, is);
2591 0 : if (error)
2592 0 : goto out;
2593 :
2594 0 : i.value = buffer;
2595 0 : i.value_len = value_size;
2596 0 : error = ext4_xattr_block_find(inode, &i, bs);
2597 0 : if (error)
2598 0 : goto out;
2599 :
2600 : /* Add entry which was removed from the inode into the block */
2601 0 : error = ext4_xattr_block_set(handle, inode, &i, bs);
2602 0 : if (error)
2603 0 : goto out;
2604 : error = 0;
2605 0 : out:
2606 0 : kfree(b_entry_name);
2607 0 : kfree(buffer);
2608 0 : if (is)
2609 0 : brelse(is->iloc.bh);
2610 0 : if (bs)
2611 0 : brelse(bs->bh);
2612 0 : kfree(is);
2613 0 : kfree(bs);
2614 :
2615 0 : return error;
2616 : }
2617 :
2618 0 : static int ext4_xattr_make_inode_space(handle_t *handle, struct inode *inode,
2619 : struct ext4_inode *raw_inode,
2620 : int isize_diff, size_t ifree,
2621 : size_t bfree, int *total_ino)
2622 : {
2623 0 : struct ext4_xattr_ibody_header *header = IHDR(inode, raw_inode);
2624 0 : struct ext4_xattr_entry *small_entry;
2625 0 : struct ext4_xattr_entry *entry;
2626 0 : struct ext4_xattr_entry *last;
2627 0 : unsigned int entry_size; /* EA entry size */
2628 0 : unsigned int total_size; /* EA entry size + value size */
2629 0 : unsigned int min_total_size;
2630 0 : int error;
2631 :
2632 0 : while (isize_diff > ifree) {
2633 0 : entry = NULL;
2634 0 : small_entry = NULL;
2635 0 : min_total_size = ~0U;
2636 0 : last = IFIRST(header);
2637 : /* Find the entry best suited to be pushed into EA block */
2638 0 : for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) {
2639 : /* never move system.data out of the inode */
2640 0 : if ((last->e_name_len == 4) &&
2641 0 : (last->e_name_index == EXT4_XATTR_INDEX_SYSTEM) &&
2642 0 : !memcmp(last->e_name, "data", 4))
2643 0 : continue;
2644 0 : total_size = EXT4_XATTR_LEN(last->e_name_len);
2645 0 : if (!last->e_value_inum)
2646 0 : total_size += EXT4_XATTR_SIZE(
2647 : le32_to_cpu(last->e_value_size));
2648 0 : if (total_size <= bfree &&
2649 : total_size < min_total_size) {
2650 0 : if (total_size + ifree < isize_diff) {
2651 : small_entry = last;
2652 : } else {
2653 0 : entry = last;
2654 0 : min_total_size = total_size;
2655 : }
2656 : }
2657 : }
2658 :
2659 0 : if (entry == NULL) {
2660 0 : if (small_entry == NULL)
2661 : return -ENOSPC;
2662 : entry = small_entry;
2663 : }
2664 :
2665 0 : entry_size = EXT4_XATTR_LEN(entry->e_name_len);
2666 0 : total_size = entry_size;
2667 0 : if (!entry->e_value_inum)
2668 0 : total_size += EXT4_XATTR_SIZE(
2669 : le32_to_cpu(entry->e_value_size));
2670 0 : error = ext4_xattr_move_to_block(handle, inode, raw_inode,
2671 : entry);
2672 0 : if (error)
2673 0 : return error;
2674 :
2675 0 : *total_ino -= entry_size;
2676 0 : ifree += total_size;
2677 0 : bfree -= total_size;
2678 : }
2679 :
2680 : return 0;
2681 : }
2682 :
2683 : /*
2684 : * Expand an inode by new_extra_isize bytes when EAs are present.
2685 : * Returns 0 on success or negative error number on failure.
2686 : */
2687 0 : int ext4_expand_extra_isize_ea(struct inode *inode, int new_extra_isize,
2688 : struct ext4_inode *raw_inode, handle_t *handle)
2689 : {
2690 0 : struct ext4_xattr_ibody_header *header;
2691 0 : struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
2692 0 : static unsigned int mnt_count;
2693 0 : size_t min_offs;
2694 0 : size_t ifree, bfree;
2695 0 : int total_ino;
2696 0 : void *base, *end;
2697 0 : int error = 0, tried_min_extra_isize = 0;
2698 0 : int s_min_extra_isize = le16_to_cpu(sbi->s_es->s_min_extra_isize);
2699 0 : int isize_diff; /* How much do we need to grow i_extra_isize */
2700 :
2701 : retry:
2702 0 : isize_diff = new_extra_isize - EXT4_I(inode)->i_extra_isize;
2703 0 : if (EXT4_I(inode)->i_extra_isize >= new_extra_isize)
2704 : return 0;
2705 :
2706 0 : header = IHDR(inode, raw_inode);
2707 :
2708 : /*
2709 : * Check if enough free space is available in the inode to shift the
2710 : * entries ahead by new_extra_isize.
2711 : */
2712 :
2713 0 : base = IFIRST(header);
2714 0 : end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size;
2715 0 : min_offs = end - base;
2716 0 : total_ino = sizeof(struct ext4_xattr_ibody_header) + sizeof(u32);
2717 :
2718 0 : error = xattr_check_inode(inode, header, end);
2719 0 : if (error)
2720 0 : goto cleanup;
2721 :
2722 0 : ifree = ext4_xattr_free_space(base, &min_offs, base, &total_ino);
2723 0 : if (ifree >= isize_diff)
2724 0 : goto shift;
2725 :
2726 : /*
2727 : * Enough free space isn't available in the inode, check if
2728 : * EA block can hold new_extra_isize bytes.
2729 : */
2730 0 : if (EXT4_I(inode)->i_file_acl) {
2731 0 : struct buffer_head *bh;
2732 :
2733 0 : bh = ext4_sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl, REQ_PRIO);
2734 0 : if (IS_ERR(bh)) {
2735 0 : error = PTR_ERR(bh);
2736 0 : goto cleanup;
2737 : }
2738 0 : error = ext4_xattr_check_block(inode, bh);
2739 0 : if (error) {
2740 0 : brelse(bh);
2741 0 : goto cleanup;
2742 : }
2743 0 : base = BHDR(bh);
2744 0 : end = bh->b_data + bh->b_size;
2745 0 : min_offs = end - base;
2746 0 : bfree = ext4_xattr_free_space(BFIRST(bh), &min_offs, base,
2747 : NULL);
2748 0 : brelse(bh);
2749 0 : if (bfree + ifree < isize_diff) {
2750 0 : if (!tried_min_extra_isize && s_min_extra_isize) {
2751 0 : tried_min_extra_isize++;
2752 0 : new_extra_isize = s_min_extra_isize;
2753 0 : goto retry;
2754 : }
2755 0 : error = -ENOSPC;
2756 0 : goto cleanup;
2757 : }
2758 : } else {
2759 0 : bfree = inode->i_sb->s_blocksize;
2760 : }
2761 :
2762 0 : error = ext4_xattr_make_inode_space(handle, inode, raw_inode,
2763 : isize_diff, ifree, bfree,
2764 : &total_ino);
2765 0 : if (error) {
2766 0 : if (error == -ENOSPC && !tried_min_extra_isize &&
2767 : s_min_extra_isize) {
2768 0 : tried_min_extra_isize++;
2769 0 : new_extra_isize = s_min_extra_isize;
2770 0 : goto retry;
2771 : }
2772 0 : goto cleanup;
2773 : }
2774 0 : shift:
2775 : /* Adjust the offsets and shift the remaining entries ahead */
2776 0 : ext4_xattr_shift_entries(IFIRST(header), EXT4_I(inode)->i_extra_isize
2777 : - new_extra_isize, (void *)raw_inode +
2778 0 : EXT4_GOOD_OLD_INODE_SIZE + new_extra_isize,
2779 : (void *)header, total_ino);
2780 0 : EXT4_I(inode)->i_extra_isize = new_extra_isize;
2781 :
2782 0 : cleanup:
2783 0 : if (error && (mnt_count != le16_to_cpu(sbi->s_es->s_mnt_count))) {
2784 0 : ext4_warning(inode->i_sb, "Unable to expand inode %lu. Delete some EAs or run e2fsck.",
2785 : inode->i_ino);
2786 0 : mnt_count = le16_to_cpu(sbi->s_es->s_mnt_count);
2787 : }
2788 : return error;
2789 : }
2790 :
2791 : #define EIA_INCR 16 /* must be 2^n */
2792 : #define EIA_MASK (EIA_INCR - 1)
2793 :
2794 : /* Add the large xattr @inode into @ea_inode_array for deferred iput().
2795 : * If @ea_inode_array is new or full it will be grown and the old
2796 : * contents copied over.
2797 : */
2798 : static int
2799 0 : ext4_expand_inode_array(struct ext4_xattr_inode_array **ea_inode_array,
2800 : struct inode *inode)
2801 : {
2802 0 : if (*ea_inode_array == NULL) {
2803 : /*
2804 : * Start with 15 inodes, so it fits into a power-of-two size.
2805 : * If *ea_inode_array is NULL, this is essentially offsetof()
2806 : */
2807 0 : (*ea_inode_array) =
2808 0 : kmalloc(offsetof(struct ext4_xattr_inode_array,
2809 : inodes[EIA_MASK]),
2810 : GFP_NOFS);
2811 0 : if (*ea_inode_array == NULL)
2812 : return -ENOMEM;
2813 0 : (*ea_inode_array)->count = 0;
2814 0 : } else if (((*ea_inode_array)->count & EIA_MASK) == EIA_MASK) {
2815 : /* expand the array once all 15 + n * 16 slots are full */
2816 0 : struct ext4_xattr_inode_array *new_array = NULL;
2817 0 : int count = (*ea_inode_array)->count;
2818 :
2819 : /* if new_array is NULL, this is essentially offsetof() */
2820 0 : new_array = kmalloc(
2821 0 : offsetof(struct ext4_xattr_inode_array,
2822 : inodes[count + EIA_INCR]),
2823 : GFP_NOFS);
2824 0 : if (new_array == NULL)
2825 : return -ENOMEM;
2826 0 : memcpy(new_array, *ea_inode_array,
2827 : offsetof(struct ext4_xattr_inode_array, inodes[count]));
2828 0 : kfree(*ea_inode_array);
2829 0 : *ea_inode_array = new_array;
2830 : }
2831 0 : (*ea_inode_array)->inodes[(*ea_inode_array)->count++] = inode;
2832 0 : return 0;
2833 : }
2834 :
2835 : /*
2836 : * ext4_xattr_delete_inode()
2837 : *
2838 : * Free extended attribute resources associated with this inode. Traverse
2839 : * all entries and decrement reference on any xattr inodes associated with this
2840 : * inode. This is called immediately before an inode is freed. We have exclusive
2841 : * access to the inode. If an orphan inode is deleted it will also release its
2842 : * references on xattr block and xattr inodes.
2843 : */
2844 193 : int ext4_xattr_delete_inode(handle_t *handle, struct inode *inode,
2845 : struct ext4_xattr_inode_array **ea_inode_array,
2846 : int extra_credits)
2847 : {
2848 193 : struct buffer_head *bh = NULL;
2849 193 : struct ext4_xattr_ibody_header *header;
2850 193 : struct ext4_iloc iloc = { .bh = NULL };
2851 193 : struct ext4_xattr_entry *entry;
2852 193 : struct inode *ea_inode;
2853 193 : int error;
2854 :
2855 193 : error = ext4_journal_ensure_credits(handle, extra_credits,
2856 : ext4_free_metadata_revoke_credits(inode->i_sb, 1));
2857 193 : if (error < 0) {
2858 0 : EXT4_ERROR_INODE(inode, "ensure credits (error %d)", error);
2859 0 : goto cleanup;
2860 : }
2861 :
2862 193 : if (ext4_has_feature_ea_inode(inode->i_sb) &&
2863 0 : ext4_test_inode_state(inode, EXT4_STATE_XATTR)) {
2864 :
2865 0 : error = ext4_get_inode_loc(inode, &iloc);
2866 0 : if (error) {
2867 0 : EXT4_ERROR_INODE(inode, "inode loc (error %d)", error);
2868 0 : goto cleanup;
2869 : }
2870 :
2871 0 : error = ext4_journal_get_write_access(handle, iloc.bh);
2872 0 : if (error) {
2873 0 : EXT4_ERROR_INODE(inode, "write access (error %d)",
2874 : error);
2875 0 : goto cleanup;
2876 : }
2877 :
2878 0 : header = IHDR(inode, ext4_raw_inode(&iloc));
2879 0 : if (header->h_magic == cpu_to_le32(EXT4_XATTR_MAGIC))
2880 0 : ext4_xattr_inode_dec_ref_all(handle, inode, iloc.bh,
2881 0 : IFIRST(header),
2882 : false /* block_csum */,
2883 : ea_inode_array,
2884 : extra_credits,
2885 : false /* skip_quota */);
2886 : }
2887 :
2888 193 : if (EXT4_I(inode)->i_file_acl) {
2889 0 : bh = ext4_sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl, REQ_PRIO);
2890 0 : if (IS_ERR(bh)) {
2891 0 : error = PTR_ERR(bh);
2892 0 : if (error == -EIO) {
2893 0 : EXT4_ERROR_INODE_ERR(inode, EIO,
2894 : "block %llu read error",
2895 : EXT4_I(inode)->i_file_acl);
2896 : }
2897 0 : bh = NULL;
2898 0 : goto cleanup;
2899 : }
2900 0 : error = ext4_xattr_check_block(inode, bh);
2901 0 : if (error)
2902 0 : goto cleanup;
2903 :
2904 0 : if (ext4_has_feature_ea_inode(inode->i_sb)) {
2905 0 : for (entry = BFIRST(bh); !IS_LAST_ENTRY(entry);
2906 0 : entry = EXT4_XATTR_NEXT(entry)) {
2907 0 : if (!entry->e_value_inum)
2908 0 : continue;
2909 0 : error = ext4_xattr_inode_iget(inode,
2910 : le32_to_cpu(entry->e_value_inum),
2911 0 : le32_to_cpu(entry->e_hash),
2912 : &ea_inode);
2913 0 : if (error)
2914 0 : continue;
2915 0 : ext4_xattr_inode_free_quota(inode, ea_inode,
2916 0 : le32_to_cpu(entry->e_value_size));
2917 0 : iput(ea_inode);
2918 : }
2919 :
2920 : }
2921 :
2922 0 : ext4_xattr_release_block(handle, inode, bh, ea_inode_array,
2923 : extra_credits);
2924 : /*
2925 : * Update i_file_acl value in the same transaction that releases
2926 : * block.
2927 : */
2928 0 : EXT4_I(inode)->i_file_acl = 0;
2929 0 : error = ext4_mark_inode_dirty(handle, inode);
2930 0 : if (error) {
2931 0 : EXT4_ERROR_INODE(inode, "mark inode dirty (error %d)",
2932 : error);
2933 0 : goto cleanup;
2934 : }
2935 0 : ext4_fc_mark_ineligible(inode->i_sb, EXT4_FC_REASON_XATTR);
2936 : }
2937 : error = 0;
2938 193 : cleanup:
2939 193 : brelse(iloc.bh);
2940 193 : brelse(bh);
2941 193 : return error;
2942 : }
2943 :
2944 193 : void ext4_xattr_inode_array_free(struct ext4_xattr_inode_array *ea_inode_array)
2945 : {
2946 193 : int idx;
2947 :
2948 193 : if (ea_inode_array == NULL)
2949 : return;
2950 :
2951 0 : for (idx = 0; idx < ea_inode_array->count; ++idx)
2952 0 : iput(ea_inode_array->inodes[idx]);
2953 0 : kfree(ea_inode_array);
2954 : }
2955 :
2956 : /*
2957 : * ext4_xattr_block_cache_insert()
2958 : *
2959 : * Create a new entry in the extended attribute block cache, and insert
2960 : * it unless such an entry is already in the cache.
2961 : *
2962 : * Returns 0, or a negative error number on failure.
2963 : */
2964 : static void
2965 0 : ext4_xattr_block_cache_insert(struct mb_cache *ea_block_cache,
2966 : struct buffer_head *bh)
2967 : {
2968 0 : struct ext4_xattr_header *header = BHDR(bh);
2969 0 : __u32 hash = le32_to_cpu(header->h_hash);
2970 0 : int reusable = le32_to_cpu(header->h_refcount) <
2971 : EXT4_XATTR_REFCOUNT_MAX;
2972 0 : int error;
2973 :
2974 0 : if (!ea_block_cache)
2975 : return;
2976 0 : error = mb_cache_entry_create(ea_block_cache, GFP_NOFS, hash,
2977 : bh->b_blocknr, reusable);
2978 0 : if (error) {
2979 : if (error == -EBUSY)
2980 : ea_bdebug(bh, "already in cache");
2981 : } else
2982 : ea_bdebug(bh, "inserting [%x]", (int)hash);
2983 : }
2984 :
2985 : /*
2986 : * ext4_xattr_cmp()
2987 : *
2988 : * Compare two extended attribute blocks for equality.
2989 : *
2990 : * Returns 0 if the blocks are equal, 1 if they differ, and
2991 : * a negative error number on errors.
2992 : */
2993 : static int
2994 0 : ext4_xattr_cmp(struct ext4_xattr_header *header1,
2995 : struct ext4_xattr_header *header2)
2996 : {
2997 0 : struct ext4_xattr_entry *entry1, *entry2;
2998 :
2999 0 : entry1 = ENTRY(header1+1);
3000 0 : entry2 = ENTRY(header2+1);
3001 0 : while (!IS_LAST_ENTRY(entry1)) {
3002 0 : if (IS_LAST_ENTRY(entry2))
3003 : return 1;
3004 0 : if (entry1->e_hash != entry2->e_hash ||
3005 0 : entry1->e_name_index != entry2->e_name_index ||
3006 0 : entry1->e_name_len != entry2->e_name_len ||
3007 0 : entry1->e_value_size != entry2->e_value_size ||
3008 0 : entry1->e_value_inum != entry2->e_value_inum ||
3009 0 : memcmp(entry1->e_name, entry2->e_name, entry1->e_name_len))
3010 : return 1;
3011 0 : if (!entry1->e_value_inum &&
3012 0 : memcmp((char *)header1 + le16_to_cpu(entry1->e_value_offs),
3013 0 : (char *)header2 + le16_to_cpu(entry2->e_value_offs),
3014 : le32_to_cpu(entry1->e_value_size)))
3015 : return 1;
3016 :
3017 0 : entry1 = EXT4_XATTR_NEXT(entry1);
3018 0 : entry2 = EXT4_XATTR_NEXT(entry2);
3019 : }
3020 0 : if (!IS_LAST_ENTRY(entry2))
3021 0 : return 1;
3022 : return 0;
3023 : }
3024 :
3025 : /*
3026 : * ext4_xattr_block_cache_find()
3027 : *
3028 : * Find an identical extended attribute block.
3029 : *
3030 : * Returns a pointer to the block found, or NULL if such a block was
3031 : * not found or an error occurred.
3032 : */
3033 : static struct buffer_head *
3034 0 : ext4_xattr_block_cache_find(struct inode *inode,
3035 : struct ext4_xattr_header *header,
3036 : struct mb_cache_entry **pce)
3037 : {
3038 0 : __u32 hash = le32_to_cpu(header->h_hash);
3039 0 : struct mb_cache_entry *ce;
3040 0 : struct mb_cache *ea_block_cache = EA_BLOCK_CACHE(inode);
3041 :
3042 0 : if (!ea_block_cache)
3043 : return NULL;
3044 0 : if (!header->h_hash)
3045 : return NULL; /* never share */
3046 0 : ea_idebug(inode, "looking for cached blocks [%x]", (int)hash);
3047 0 : ce = mb_cache_entry_find_first(ea_block_cache, hash);
3048 0 : while (ce) {
3049 0 : struct buffer_head *bh;
3050 :
3051 0 : bh = ext4_sb_bread(inode->i_sb, ce->e_value, REQ_PRIO);
3052 0 : if (IS_ERR(bh)) {
3053 0 : if (PTR_ERR(bh) == -ENOMEM)
3054 : return NULL;
3055 0 : bh = NULL;
3056 0 : EXT4_ERROR_INODE(inode, "block %lu read error",
3057 : (unsigned long)ce->e_value);
3058 0 : } else if (ext4_xattr_cmp(header, BHDR(bh)) == 0) {
3059 0 : *pce = ce;
3060 0 : return bh;
3061 : }
3062 0 : brelse(bh);
3063 0 : ce = mb_cache_entry_find_next(ea_block_cache, ce);
3064 : }
3065 : return NULL;
3066 : }
3067 :
3068 : #define NAME_HASH_SHIFT 5
3069 : #define VALUE_HASH_SHIFT 16
3070 :
3071 : /*
3072 : * ext4_xattr_hash_entry()
3073 : *
3074 : * Compute the hash of an extended attribute.
3075 : */
3076 0 : static __le32 ext4_xattr_hash_entry(char *name, size_t name_len, __le32 *value,
3077 : size_t value_count)
3078 : {
3079 0 : __u32 hash = 0;
3080 :
3081 0 : while (name_len--) {
3082 0 : hash = (hash << NAME_HASH_SHIFT) ^
3083 : (hash >> (8*sizeof(hash) - NAME_HASH_SHIFT)) ^
3084 0 : *name++;
3085 : }
3086 0 : while (value_count--) {
3087 0 : hash = (hash << VALUE_HASH_SHIFT) ^
3088 : (hash >> (8*sizeof(hash) - VALUE_HASH_SHIFT)) ^
3089 0 : le32_to_cpu(*value++);
3090 : }
3091 0 : return cpu_to_le32(hash);
3092 : }
3093 :
3094 : #undef NAME_HASH_SHIFT
3095 : #undef VALUE_HASH_SHIFT
3096 :
3097 : #define BLOCK_HASH_SHIFT 16
3098 :
3099 : /*
3100 : * ext4_xattr_rehash()
3101 : *
3102 : * Re-compute the extended attribute hash value after an entry has changed.
3103 : */
3104 0 : static void ext4_xattr_rehash(struct ext4_xattr_header *header)
3105 : {
3106 0 : struct ext4_xattr_entry *here;
3107 0 : __u32 hash = 0;
3108 :
3109 0 : here = ENTRY(header+1);
3110 0 : while (!IS_LAST_ENTRY(here)) {
3111 0 : if (!here->e_hash) {
3112 : /* Block is not shared if an entry's hash value == 0 */
3113 : hash = 0;
3114 : break;
3115 : }
3116 0 : hash = (hash << BLOCK_HASH_SHIFT) ^
3117 : (hash >> (8*sizeof(hash) - BLOCK_HASH_SHIFT)) ^
3118 : le32_to_cpu(here->e_hash);
3119 0 : here = EXT4_XATTR_NEXT(here);
3120 : }
3121 0 : header->h_hash = cpu_to_le32(hash);
3122 0 : }
3123 :
3124 : #undef BLOCK_HASH_SHIFT
3125 :
3126 : #define HASH_BUCKET_BITS 10
3127 :
3128 : struct mb_cache *
3129 1 : ext4_xattr_create_cache(void)
3130 : {
3131 1 : return mb_cache_create(HASH_BUCKET_BITS);
3132 : }
3133 :
3134 0 : void ext4_xattr_destroy_cache(struct mb_cache *cache)
3135 : {
3136 0 : if (cache)
3137 0 : mb_cache_destroy(cache);
3138 0 : }
3139 :
|
