2 Trivial Database 2: free list/block handling
3 Copyright (C) Rusty Russell 2010
5 This library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 3 of the License, or (at your option) any later version.
10 This library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
15 You should have received a copy of the GNU Lesser General Public
16 License along with this library; if not, see <http://www.gnu.org/licenses/>.
19 #include <ccan/likely/likely.h>
20 #include <ccan/asearch/asearch.h>
22 /* We keep an ordered array of offsets. */
23 static bool append(tdb_off_t **arr, size_t *num, tdb_off_t off)
25 tdb_off_t *new = realloc(*arr, (*num + 1) * sizeof(tdb_off_t));
33 static enum TDB_ERROR check_header(struct tdb_context *tdb, tdb_off_t *recovery,
34 uint64_t *features, size_t *num_capabilities)
37 struct tdb_header hdr;
41 ecode = tdb_read_convert(tdb, 0, &hdr, sizeof(hdr));
42 if (ecode != TDB_SUCCESS) {
45 /* magic food should not be converted, so convert back. */
46 tdb_convert(tdb, hdr.magic_food, sizeof(hdr.magic_food));
48 hash_test = TDB_HASH_MAGIC;
49 hash_test = tdb_hash(tdb, &hash_test, sizeof(hash_test));
50 if (hdr.hash_test != hash_test) {
51 return tdb_logerr(tdb, TDB_ERR_CORRUPT, TDB_LOG_ERROR,
52 "check: hash test %llu should be %llu",
53 (long long)hdr.hash_test,
54 (long long)hash_test);
57 if (strcmp(hdr.magic_food, TDB_MAGIC_FOOD) != 0) {
58 return tdb_logerr(tdb, TDB_ERR_CORRUPT, TDB_LOG_ERROR,
59 "check: bad magic '%.*s'",
60 (unsigned)sizeof(hdr.magic_food),
64 /* Features which are used must be a subset of features offered. */
65 if (hdr.features_used & ~hdr.features_offered) {
66 return tdb_logerr(tdb, TDB_ERR_CORRUPT, TDB_LOG_ERROR,
67 "check: features used (0x%llx) which"
68 " are not offered (0x%llx)",
69 (long long)hdr.features_used,
70 (long long)hdr.features_offered);
73 *features = hdr.features_offered;
74 *recovery = hdr.recovery;
76 if (*recovery < sizeof(hdr)
77 || *recovery > tdb->file->map_size) {
78 return tdb_logerr(tdb, TDB_ERR_CORRUPT, TDB_LOG_ERROR,
80 " invalid recovery offset %zu",
85 for (off = hdr.capabilities; off && ecode == TDB_SUCCESS; off = next) {
86 const struct tdb_capability *cap;
89 cap = tdb_access_read(tdb, off, sizeof(*cap), true);
90 if (TDB_PTR_IS_ERR(cap)) {
91 return TDB_PTR_ERR(cap);
94 /* All capabilities are unknown. */
95 err = unknown_capability(tdb, "tdb_check", cap->type);
97 tdb_access_release(tdb, cap);
100 (*num_capabilities)++;
103 /* Don't check reserved: they *can* be used later. */
107 static enum TDB_ERROR check_hash_tree(struct tdb_context *tdb,
108 tdb_off_t off, unsigned int group_bits,
110 unsigned hprefix_bits,
114 enum TDB_ERROR (*check)(TDB_DATA,
118 static enum TDB_ERROR check_hash_chain(struct tdb_context *tdb,
124 enum TDB_ERROR (*check)(TDB_DATA,
129 struct tdb_used_record rec;
130 enum TDB_ERROR ecode;
132 ecode = tdb_read_convert(tdb, off, &rec, sizeof(rec));
133 if (ecode != TDB_SUCCESS) {
137 if (rec_magic(&rec) != TDB_CHAIN_MAGIC) {
138 return tdb_logerr(tdb, TDB_ERR_CORRUPT, TDB_LOG_ERROR,
139 "tdb_check: Bad hash chain magic %llu",
140 (long long)rec_magic(&rec));
143 if (rec_data_length(&rec) != sizeof(struct tdb_chain)) {
144 return tdb_logerr(tdb, TDB_ERR_CORRUPT, TDB_LOG_ERROR,
146 " Bad hash chain length %llu vs %zu",
147 (long long)rec_data_length(&rec),
148 sizeof(struct tdb_chain));
150 if (rec_key_length(&rec) != 0) {
151 return tdb_logerr(tdb, TDB_ERR_CORRUPT, TDB_LOG_ERROR,
152 "tdb_check: Bad hash chain key length %llu",
153 (long long)rec_key_length(&rec));
155 if (rec_hash(&rec) != 0) {
156 return tdb_logerr(tdb, TDB_ERR_CORRUPT, TDB_LOG_ERROR,
157 "tdb_check: Bad hash chain hash value %llu",
158 (long long)rec_hash(&rec));
162 ecode = check_hash_tree(tdb, off, 0, hash, 64,
163 used, num_used, num_found, check, data);
164 if (ecode != TDB_SUCCESS) {
168 off = tdb_read_off(tdb, off + offsetof(struct tdb_chain, next));
169 if (TDB_OFF_IS_ERR(off)) {
170 return TDB_OFF_TO_ERR(off);
175 return check_hash_chain(tdb, off, hash, used, num_used, num_found,
179 static enum TDB_ERROR check_hash_record(struct tdb_context *tdb,
182 unsigned hprefix_bits,
186 enum TDB_ERROR (*check)(TDB_DATA,
191 struct tdb_used_record rec;
192 enum TDB_ERROR ecode;
194 if (hprefix_bits >= 64)
195 return check_hash_chain(tdb, off, hprefix, used, num_used,
196 num_found, check, data);
198 ecode = tdb_read_convert(tdb, off, &rec, sizeof(rec));
199 if (ecode != TDB_SUCCESS) {
203 if (rec_magic(&rec) != TDB_HTABLE_MAGIC) {
204 return tdb_logerr(tdb, TDB_ERR_CORRUPT, TDB_LOG_ERROR,
205 "tdb_check: Bad hash table magic %llu",
206 (long long)rec_magic(&rec));
208 if (rec_data_length(&rec)
209 != sizeof(tdb_off_t) << TDB_SUBLEVEL_HASH_BITS) {
210 return tdb_logerr(tdb, TDB_ERR_CORRUPT, TDB_LOG_ERROR,
212 " Bad hash table length %llu vs %llu",
213 (long long)rec_data_length(&rec),
214 (long long)sizeof(tdb_off_t)
215 << TDB_SUBLEVEL_HASH_BITS);
217 if (rec_key_length(&rec) != 0) {
218 return tdb_logerr(tdb, TDB_ERR_CORRUPT, TDB_LOG_ERROR,
219 "tdb_check: Bad hash table key length %llu",
220 (long long)rec_key_length(&rec));
222 if (rec_hash(&rec) != 0) {
223 return tdb_logerr(tdb, TDB_ERR_CORRUPT, TDB_LOG_ERROR,
224 "tdb_check: Bad hash table hash value %llu",
225 (long long)rec_hash(&rec));
229 return check_hash_tree(tdb, off,
230 TDB_SUBLEVEL_HASH_BITS-TDB_HASH_GROUP_BITS,
231 hprefix, hprefix_bits,
232 used, num_used, num_found, check, data);
235 static int off_cmp(const tdb_off_t *a, const tdb_off_t *b)
237 /* Can overflow an int. */
243 static uint64_t get_bits(uint64_t h, unsigned num, unsigned *used)
247 return (h >> (64 - *used)) & ((1U << num) - 1);
250 static enum TDB_ERROR check_hash_tree(struct tdb_context *tdb,
251 tdb_off_t off, unsigned int group_bits,
253 unsigned hprefix_bits,
257 enum TDB_ERROR (*check)(TDB_DATA,
262 const tdb_off_t *hash;
263 struct tdb_used_record rec;
264 enum TDB_ERROR ecode;
266 hash = tdb_access_read(tdb, off,
268 << (group_bits + TDB_HASH_GROUP_BITS),
270 if (TDB_PTR_IS_ERR(hash)) {
271 return TDB_PTR_ERR(hash);
274 for (g = 0; g < (1 << group_bits); g++) {
275 const tdb_off_t *group = hash + (g << TDB_HASH_GROUP_BITS);
276 for (b = 0; b < (1 << TDB_HASH_GROUP_BITS); b++) {
277 unsigned int bucket, i, used_bits;
283 off = group[b] & TDB_OFF_MASK;
284 p = asearch(&off, used, num_used, off_cmp);
286 ecode = tdb_logerr(tdb, TDB_ERR_CORRUPT,
288 "tdb_check: Invalid offset"
293 /* Mark it invalid. */
297 if (hprefix_bits == 64) {
298 /* Chained entries are unordered. */
299 if (is_subhash(group[b])) {
300 ecode = TDB_ERR_CORRUPT;
301 tdb_logerr(tdb, ecode,
303 "tdb_check: Invalid chain"
307 h = hash_record(tdb, off);
309 ecode = TDB_ERR_CORRUPT;
310 tdb_logerr(tdb, ecode,
312 "check: bad hash chain"
319 ecode = tdb_read_convert(tdb, off, &rec,
321 if (ecode != TDB_SUCCESS) {
327 if (is_subhash(group[b])) {
330 << (group_bits + TDB_HASH_GROUP_BITS))
331 + g * (1 << TDB_HASH_GROUP_BITS) + b;
333 ecode = check_hash_record(tdb,
334 group[b] & TDB_OFF_MASK,
338 + TDB_HASH_GROUP_BITS,
339 used, num_used, num_found,
341 if (ecode != TDB_SUCCESS) {
348 /* Does it belong here at all? */
349 h = hash_record(tdb, off);
351 if (get_bits(h, hprefix_bits, &used_bits) != hprefix
353 ecode = tdb_logerr(tdb, TDB_ERR_CORRUPT,
355 "check: bad hash placement"
362 /* Does it belong in this group? */
363 if (get_bits(h, group_bits, &used_bits) != g) {
364 ecode = tdb_logerr(tdb, TDB_ERR_CORRUPT,
366 "check: bad group %llu"
372 /* Are bucket bits correct? */
373 bucket = group[b] & TDB_OFF_HASH_GROUP_MASK;
374 if (get_bits(h, TDB_HASH_GROUP_BITS, &used_bits)
376 used_bits -= TDB_HASH_GROUP_BITS;
377 ecode = tdb_logerr(tdb, TDB_ERR_CORRUPT,
379 "check: bad bucket %u vs %u",
380 (unsigned)get_bits(h,
387 /* There must not be any zero entries between
388 * the bucket it belongs in and this one! */
391 i = (i + 1) % (1 << TDB_HASH_GROUP_BITS)) {
393 ecode = TDB_ERR_CORRUPT;
394 tdb_logerr(tdb, ecode,
396 "check: bad group placement"
403 ecode = tdb_read_convert(tdb, off, &rec, sizeof(rec));
404 if (ecode != TDB_SUCCESS) {
408 /* Bottom bits must match header. */
409 if ((h & ((1 << 11)-1)) != rec_hash(&rec)) {
410 ecode = tdb_logerr(tdb, TDB_ERR_CORRUPT,
412 "tdb_check: Bad hash magic"
414 " (0x%llx vs 0x%llx)",
417 (long long)rec_hash(&rec));
424 const unsigned char *kptr;
426 kptr = tdb_access_read(tdb,
429 + rec_data_length(&rec),
431 if (TDB_PTR_IS_ERR(kptr)) {
432 ecode = TDB_PTR_ERR(kptr);
436 k = tdb_mkdata(kptr, rec_key_length(&rec));
437 d = tdb_mkdata(kptr + k.dsize,
438 rec_data_length(&rec));
439 ecode = check(k, d, data);
440 tdb_access_release(tdb, kptr);
441 if (ecode != TDB_SUCCESS) {
447 tdb_access_release(tdb, hash);
451 tdb_access_release(tdb, hash);
455 static enum TDB_ERROR check_hash(struct tdb_context *tdb,
457 size_t num_used, size_t num_other_used,
458 enum TDB_ERROR (*check)(TDB_DATA, TDB_DATA, void *),
461 /* Free tables and capabilities also show up as used. */
462 size_t num_found = num_other_used;
463 enum TDB_ERROR ecode;
465 ecode = check_hash_tree(tdb, offsetof(struct tdb_header, hashtable),
466 TDB_TOPLEVEL_HASH_BITS-TDB_HASH_GROUP_BITS,
467 0, 0, used, num_used, &num_found,
469 if (ecode == TDB_SUCCESS) {
470 if (num_found != num_used) {
471 ecode = tdb_logerr(tdb, TDB_ERR_CORRUPT, TDB_LOG_ERROR,
472 "tdb_check: Not all entries"
479 static enum TDB_ERROR check_free(struct tdb_context *tdb,
481 const struct tdb_free_record *frec,
482 tdb_off_t prev, unsigned int ftable,
485 enum TDB_ERROR ecode;
487 if (frec_magic(frec) != TDB_FREE_MAGIC) {
488 return tdb_logerr(tdb, TDB_ERR_CORRUPT, TDB_LOG_ERROR,
489 "tdb_check: offset %llu bad magic 0x%llx",
491 (long long)frec->magic_and_prev);
493 if (frec_ftable(frec) != ftable) {
494 return tdb_logerr(tdb, TDB_ERR_CORRUPT, TDB_LOG_ERROR,
495 "tdb_check: offset %llu bad freetable %u",
496 (long long)off, frec_ftable(frec));
500 ecode = tdb->tdb2.io->oob(tdb, off
502 + sizeof(struct tdb_used_record),
504 if (ecode != TDB_SUCCESS) {
507 if (size_to_bucket(frec_len(frec)) != bucket) {
508 return tdb_logerr(tdb, TDB_ERR_CORRUPT, TDB_LOG_ERROR,
509 "tdb_check: offset %llu in wrong bucket"
512 bucket, size_to_bucket(frec_len(frec)));
514 if (prev && prev != frec_prev(frec)) {
515 return tdb_logerr(tdb, TDB_ERR_CORRUPT, TDB_LOG_ERROR,
516 "tdb_check: offset %llu bad prev"
519 (long long)prev, (long long)frec_len(frec));
524 static enum TDB_ERROR check_free_table(struct tdb_context *tdb,
525 tdb_off_t ftable_off,
531 struct tdb_freetable ft;
534 enum TDB_ERROR ecode;
536 ecode = tdb_read_convert(tdb, ftable_off, &ft, sizeof(ft));
537 if (ecode != TDB_SUCCESS) {
541 if (rec_magic(&ft.hdr) != TDB_FTABLE_MAGIC
542 || rec_key_length(&ft.hdr) != 0
543 || rec_data_length(&ft.hdr) != sizeof(ft) - sizeof(ft.hdr)
544 || rec_hash(&ft.hdr) != 0) {
545 return tdb_logerr(tdb, TDB_ERR_CORRUPT, TDB_LOG_ERROR,
546 "tdb_check: Invalid header on free table");
549 for (i = 0; i < TDB_FREE_BUCKETS; i++) {
550 tdb_off_t off, prev = 0, *p, first = 0;
551 struct tdb_free_record f;
553 h = bucket_off(ftable_off, i);
554 for (off = tdb_read_off(tdb, h); off; off = f.next) {
555 if (TDB_OFF_IS_ERR(off)) {
556 return TDB_OFF_TO_ERR(off);
562 ecode = tdb_read_convert(tdb, off, &f, sizeof(f));
563 if (ecode != TDB_SUCCESS) {
566 ecode = check_free(tdb, off, &f, prev, ftable_num, i);
567 if (ecode != TDB_SUCCESS) {
571 /* FIXME: Check hash bits */
572 p = asearch(&off, fr, num_free, off_cmp);
574 return tdb_logerr(tdb, TDB_ERR_CORRUPT,
576 "tdb_check: Invalid offset"
577 " %llu in free table",
580 /* Mark it invalid. */
587 /* Now we can check first back pointer. */
588 ecode = tdb_read_convert(tdb, first, &f, sizeof(f));
589 if (ecode != TDB_SUCCESS) {
592 ecode = check_free(tdb, first, &f, prev, ftable_num, i);
593 if (ecode != TDB_SUCCESS) {
601 /* Slow, but should be very rare. */
602 tdb_off_t dead_space(struct tdb_context *tdb, tdb_off_t off)
605 enum TDB_ERROR ecode;
607 for (len = 0; off + len < tdb->file->map_size; len++) {
609 ecode = tdb->tdb2.io->tread(tdb, off, &c, 1);
610 if (ecode != TDB_SUCCESS) {
611 return TDB_ERR_TO_OFF(ecode);
613 if (c != 0 && c != 0x43)
619 static enum TDB_ERROR check_linear(struct tdb_context *tdb,
620 tdb_off_t **used, size_t *num_used,
621 tdb_off_t **fr, size_t *num_free,
622 uint64_t features, tdb_off_t recovery)
626 enum TDB_ERROR ecode;
627 bool found_recovery = false;
629 for (off = sizeof(struct tdb_header);
630 off < tdb->file->map_size;
633 struct tdb_used_record u;
634 struct tdb_free_record f;
635 struct tdb_recovery_record r;
637 /* r is larger: only get that if we need to. */
638 ecode = tdb_read_convert(tdb, off, &rec, sizeof(rec.f));
639 if (ecode != TDB_SUCCESS) {
643 /* If we crash after ftruncate, we can get zeroes or fill. */
644 if (rec.r.magic == TDB_RECOVERY_INVALID_MAGIC
645 || rec.r.magic == 0x4343434343434343ULL) {
646 ecode = tdb_read_convert(tdb, off, &rec, sizeof(rec.r));
647 if (ecode != TDB_SUCCESS) {
650 if (recovery == off) {
651 found_recovery = true;
652 len = sizeof(rec.r) + rec.r.max_len;
654 len = dead_space(tdb, off);
655 if (TDB_OFF_IS_ERR(len)) {
656 return TDB_OFF_TO_ERR(len);
658 if (len < sizeof(rec.r)) {
659 return tdb_logerr(tdb, TDB_ERR_CORRUPT,
662 " dead space at %zu",
666 tdb_logerr(tdb, TDB_SUCCESS, TDB_LOG_WARNING,
667 "Dead space at %zu-%zu (of %zu)",
668 (size_t)off, (size_t)(off + len),
669 (size_t)tdb->file->map_size);
671 } else if (rec.r.magic == TDB_RECOVERY_MAGIC) {
672 ecode = tdb_read_convert(tdb, off, &rec, sizeof(rec.r));
673 if (ecode != TDB_SUCCESS) {
676 if (recovery != off) {
677 return tdb_logerr(tdb, TDB_ERR_CORRUPT,
679 "tdb_check: unexpected"
680 " recovery record at offset"
684 if (rec.r.len > rec.r.max_len) {
685 return tdb_logerr(tdb, TDB_ERR_CORRUPT,
687 "tdb_check: invalid recovery"
691 if (rec.r.eof > tdb->file->map_size) {
692 return tdb_logerr(tdb, TDB_ERR_CORRUPT,
694 "tdb_check: invalid old EOF"
695 " %zu", (size_t)rec.r.eof);
697 found_recovery = true;
698 len = sizeof(rec.r) + rec.r.max_len;
699 } else if (frec_magic(&rec.f) == TDB_FREE_MAGIC) {
700 len = sizeof(rec.u) + frec_len(&rec.f);
701 if (off + len > tdb->file->map_size) {
702 return tdb_logerr(tdb, TDB_ERR_CORRUPT,
704 "tdb_check: free overlength"
705 " %llu at offset %llu",
709 /* This record should be in free lists. */
710 if (frec_ftable(&rec.f) != TDB_FTABLE_NONE
711 && !append(fr, num_free, off)) {
712 return tdb_logerr(tdb, TDB_ERR_OOM,
714 "tdb_check: tracking %zu'th"
715 " free record.", *num_free);
717 } else if (rec_magic(&rec.u) == TDB_USED_MAGIC
718 || rec_magic(&rec.u) == TDB_CHAIN_MAGIC
719 || rec_magic(&rec.u) == TDB_HTABLE_MAGIC
720 || rec_magic(&rec.u) == TDB_FTABLE_MAGIC
721 || rec_magic(&rec.u) == TDB_CAP_MAGIC) {
722 uint64_t klen, dlen, extra;
724 /* This record is used! */
725 if (!append(used, num_used, off)) {
726 return tdb_logerr(tdb, TDB_ERR_OOM,
728 "tdb_check: tracking %zu'th"
729 " used record.", *num_used);
732 klen = rec_key_length(&rec.u);
733 dlen = rec_data_length(&rec.u);
734 extra = rec_extra_padding(&rec.u);
736 len = sizeof(rec.u) + klen + dlen + extra;
737 if (off + len > tdb->file->map_size) {
738 return tdb_logerr(tdb, TDB_ERR_CORRUPT,
740 "tdb_check: used overlength"
741 " %llu at offset %llu",
746 if (len < sizeof(rec.f)) {
747 return tdb_logerr(tdb, TDB_ERR_CORRUPT,
749 "tdb_check: too short record"
755 /* Check that records have correct 0 at end (but may
757 if (extra && !features
758 && rec_magic(&rec.u) != TDB_CAP_MAGIC) {
761 p = tdb_access_read(tdb, off + sizeof(rec.u)
762 + klen + dlen, 1, false);
763 if (TDB_PTR_IS_ERR(p))
764 return TDB_PTR_ERR(p);
766 tdb_access_release(tdb, p);
769 return tdb_logerr(tdb, TDB_ERR_CORRUPT,
778 return tdb_logerr(tdb, TDB_ERR_CORRUPT,
780 "tdb_check: Bad magic 0x%llx"
782 (long long)rec_magic(&rec.u),
787 /* We must have found recovery area if there was one. */
788 if (recovery != 0 && !found_recovery) {
789 return tdb_logerr(tdb, TDB_ERR_CORRUPT, TDB_LOG_ERROR,
790 "tdb_check: expected a recovery area at %zu",
797 enum TDB_ERROR tdb_check_(struct tdb_context *tdb,
798 enum TDB_ERROR (*check)(TDB_DATA, TDB_DATA, void *),
801 tdb_off_t *fr = NULL, *used = NULL, ft, recovery;
802 size_t num_free = 0, num_used = 0, num_found = 0, num_ftables = 0,
803 num_capabilities = 0;
805 enum TDB_ERROR ecode;
807 if (tdb->flags & TDB_CANT_CHECK) {
808 return tdb_logerr(tdb, TDB_SUCCESS, TDB_LOG_WARNING,
809 "tdb_check: database has unknown capability,"
813 if (tdb->flags & TDB_VERSION1) {
814 if (tdb1_check(tdb, check, data) == -1)
815 return tdb->last_error;
819 ecode = tdb_allrecord_lock(tdb, F_RDLCK, TDB_LOCK_WAIT, false);
820 if (ecode != TDB_SUCCESS) {
821 return tdb->last_error = ecode;
824 ecode = tdb_lock_expand(tdb, F_RDLCK);
825 if (ecode != TDB_SUCCESS) {
826 tdb_allrecord_unlock(tdb, F_RDLCK);
827 return tdb->last_error = ecode;
830 ecode = check_header(tdb, &recovery, &features, &num_capabilities);
831 if (ecode != TDB_SUCCESS)
834 /* First we do a linear scan, checking all records. */
835 ecode = check_linear(tdb, &used, &num_used, &fr, &num_free, features,
837 if (ecode != TDB_SUCCESS)
840 for (ft = first_ftable(tdb); ft; ft = next_ftable(tdb, ft)) {
841 if (TDB_OFF_IS_ERR(ft)) {
842 ecode = TDB_OFF_TO_ERR(ft);
845 ecode = check_free_table(tdb, ft, num_ftables, fr, num_free,
847 if (ecode != TDB_SUCCESS)
852 /* FIXME: Check key uniqueness? */
853 ecode = check_hash(tdb, used, num_used, num_ftables + num_capabilities,
855 if (ecode != TDB_SUCCESS)
858 if (num_found != num_free) {
859 ecode = tdb_logerr(tdb, TDB_ERR_CORRUPT, TDB_LOG_ERROR,
860 "tdb_check: Not all entries are in"
865 tdb_allrecord_unlock(tdb, F_RDLCK);
866 tdb_unlock_expand(tdb, F_RDLCK);
869 return tdb->last_error = ecode;