1 // SPDX-License-Identifier: GPL-2.0
4 #include "alloc_background.h"
5 #include "backpointers.h"
6 #include "btree_cache.h"
7 #include "btree_update.h"
8 #include "btree_write_buffer.h"
13 static bool extent_matches_bp(struct bch_fs *c,
14 enum btree_id btree_id, unsigned level,
17 struct bch_backpointer bp)
19 struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
20 const union bch_extent_entry *entry;
21 struct extent_ptr_decoded p;
23 bkey_for_each_ptr_decode(k.k, ptrs, p, entry) {
25 struct bch_backpointer bp2;
30 bch2_extent_ptr_to_bp(c, btree_id, level, k, p,
32 if (bpos_eq(bucket, bucket2) &&
33 !memcmp(&bp, &bp2, sizeof(bp)))
40 int bch2_backpointer_invalid(const struct bch_fs *c, struct bkey_s_c k,
41 unsigned flags, struct printbuf *err)
43 struct bkey_s_c_backpointer bp = bkey_s_c_to_backpointer(k);
44 struct bpos bucket = bp_pos_to_bucket(c, bp.k->p);
46 if (bkey_val_bytes(bp.k) < sizeof(*bp.v)) {
47 prt_str(err, "incorrect value size");
48 return -BCH_ERR_invalid_bkey;
51 if (!bpos_eq(bp.k->p, bucket_pos_to_bp(c, bucket, bp.v->bucket_offset))) {
52 prt_str(err, "backpointer at wrong pos");
53 return -BCH_ERR_invalid_bkey;
59 void bch2_backpointer_to_text(struct printbuf *out, const struct bch_backpointer *bp)
61 prt_printf(out, "btree=%s l=%u offset=%llu:%u len=%u pos=",
62 bch2_btree_ids[bp->btree_id],
64 (u64) (bp->bucket_offset >> MAX_EXTENT_COMPRESS_RATIO_SHIFT),
65 (u32) bp->bucket_offset & ~(~0U << MAX_EXTENT_COMPRESS_RATIO_SHIFT),
67 bch2_bpos_to_text(out, bp->pos);
70 void bch2_backpointer_k_to_text(struct printbuf *out, struct bch_fs *c, struct bkey_s_c k)
72 bch2_backpointer_to_text(out, bkey_s_c_to_backpointer(k).v);
75 void bch2_backpointer_swab(struct bkey_s k)
77 struct bkey_s_backpointer bp = bkey_s_to_backpointer(k);
79 bp.v->bucket_offset = swab32(bp.v->bucket_offset);
80 bp.v->bucket_len = swab32(bp.v->bucket_len);
81 bch2_bpos_swab(&bp.v->pos);
84 #define BACKPOINTER_OFFSET_MAX ((1ULL << 40) - 1)
86 static inline int backpointer_cmp(struct bch_backpointer l, struct bch_backpointer r)
88 return cmp_int(l.bucket_offset, r.bucket_offset);
91 static int bch2_backpointer_del_by_offset(struct btree_trans *trans,
94 struct bch_backpointer bp)
96 struct bch_fs *c = trans->c;
97 struct btree_iter iter;
101 if (bp_offset < BACKPOINTER_OFFSET_MAX) {
102 struct bch_backpointer *bps;
103 struct bkey_i_alloc_v4 *a;
106 bch2_trans_iter_init(trans, &iter, BTREE_ID_alloc,
110 BTREE_ITER_WITH_UPDATES);
111 k = bch2_btree_iter_peek_slot(&iter);
116 if (k.k->type != KEY_TYPE_alloc_v4) {
121 a = bch2_alloc_to_v4_mut(trans, k);
122 ret = PTR_ERR_OR_ZERO(a);
125 bps = alloc_v4_backpointers(&a->v);
126 nr = BCH_ALLOC_V4_NR_BACKPOINTERS(&a->v);
128 for (i = 0; i < nr; i++) {
129 if (bps[i].bucket_offset == bp_offset)
131 if (bps[i].bucket_offset > bp_offset)
138 if (memcmp(&bps[i], &bp, sizeof(bp))) {
142 array_remove_item(bps, nr, i);
143 SET_BCH_ALLOC_V4_NR_BACKPOINTERS(&a->v, nr);
144 set_alloc_v4_u64s(a);
145 ret = bch2_trans_update(trans, &iter, &a->k_i, 0);
147 bp_offset -= BACKPOINTER_OFFSET_MAX;
149 bch2_trans_iter_init(trans, &iter, BTREE_ID_backpointers,
150 bucket_pos_to_bp(c, bucket, bp_offset),
153 BTREE_ITER_WITH_UPDATES);
154 k = bch2_btree_iter_peek_slot(&iter);
159 if (k.k->type != KEY_TYPE_backpointer ||
160 memcmp(bkey_s_c_to_backpointer(k).v, &bp, sizeof(bp))) {
165 ret = bch2_btree_delete_at(trans, &iter, 0);
168 bch2_trans_iter_exit(trans, &iter);
172 bool bch2_bucket_backpointer_del(struct btree_trans *trans,
173 struct bkey_i_alloc_v4 *a,
174 struct bch_backpointer bp)
176 struct bch_backpointer *bps = alloc_v4_backpointers(&a->v);
177 unsigned i, nr = BCH_ALLOC_V4_NR_BACKPOINTERS(&a->v);
179 for (i = 0; i < nr; i++) {
180 int cmp = backpointer_cmp(bps[i], bp) ?:
181 memcmp(&bps[i], &bp, sizeof(bp));
183 array_remove_item(bps, nr, i);
184 SET_BCH_ALLOC_V4_NR_BACKPOINTERS(&a->v, nr);
185 set_alloc_v4_u64s(a);
195 static noinline int backpointer_mod_err(struct btree_trans *trans,
196 struct bch_backpointer bp,
197 struct bkey_s_c bp_k,
198 struct bkey_s_c orig_k,
201 struct bch_fs *c = trans->c;
202 struct printbuf buf = PRINTBUF;
205 prt_printf(&buf, "existing backpointer found when inserting ");
206 bch2_backpointer_to_text(&buf, &bp);
208 printbuf_indent_add(&buf, 2);
210 prt_printf(&buf, "found ");
211 bch2_bkey_val_to_text(&buf, c, bp_k);
214 prt_printf(&buf, "for ");
215 bch2_bkey_val_to_text(&buf, c, orig_k);
217 bch_err(c, "%s", buf.buf);
218 } else if (test_bit(BCH_FS_CHECK_BACKPOINTERS_DONE, &c->flags)) {
219 prt_printf(&buf, "backpointer not found when deleting");
221 printbuf_indent_add(&buf, 2);
223 prt_printf(&buf, "searching for ");
224 bch2_backpointer_to_text(&buf, &bp);
227 prt_printf(&buf, "got ");
228 bch2_bkey_val_to_text(&buf, c, bp_k);
231 prt_printf(&buf, "for ");
232 bch2_bkey_val_to_text(&buf, c, orig_k);
234 bch_err(c, "%s", buf.buf);
239 if (test_bit(BCH_FS_CHECK_BACKPOINTERS_DONE, &c->flags)) {
240 bch2_inconsistent_error(c);
247 int bch2_bucket_backpointer_mod_nowritebuffer(struct btree_trans *trans,
248 struct bkey_i_alloc_v4 *a,
249 struct bch_backpointer bp,
250 struct bkey_s_c orig_k,
253 struct bch_fs *c = trans->c;
254 struct bkey_i_backpointer *bp_k;
255 struct btree_iter bp_iter;
259 bp_k = bch2_trans_kmalloc_nomemzero(trans, sizeof(struct bkey_i_backpointer));
260 ret = PTR_ERR_OR_ZERO(bp_k);
264 bkey_backpointer_init(&bp_k->k_i);
265 bp_k->k.p = bucket_pos_to_bp(c, a->k.p, bp.bucket_offset);
269 bp_k->k.type = KEY_TYPE_deleted;
270 set_bkey_val_u64s(&bp_k->k, 0);
273 bch2_trans_iter_init(trans, &bp_iter, BTREE_ID_backpointers,
274 bucket_pos_to_bp(c, a->k.p, bp.bucket_offset),
277 BTREE_ITER_WITH_UPDATES);
278 k = bch2_btree_iter_peek_slot(&bp_iter);
285 : (k.k->type != KEY_TYPE_backpointer ||
286 memcmp(bkey_s_c_to_backpointer(k).v, &bp, sizeof(bp)))) {
287 ret = backpointer_mod_err(trans, bp, k, orig_k, insert);
292 ret = bch2_trans_update(trans, &bp_iter, &bp_k->k_i, 0);
294 bch2_trans_iter_exit(trans, &bp_iter);
299 * Find the next backpointer >= *bp_offset:
301 int bch2_get_next_backpointer(struct btree_trans *trans,
302 struct bpos bucket, int gen,
304 struct bch_backpointer *dst,
307 struct bch_fs *c = trans->c;
308 struct bpos bp_pos, bp_end_pos;
309 struct btree_iter alloc_iter, bp_iter = { NULL };
311 struct bkey_s_c_alloc_v4 a;
315 if (*bp_offset == U64_MAX)
318 bp_pos = bucket_pos_to_bp(c, bucket,
319 max(*bp_offset, BACKPOINTER_OFFSET_MAX) - BACKPOINTER_OFFSET_MAX);
320 bp_end_pos = bucket_pos_to_bp(c, bpos_nosnap_successor(bucket), 0);
322 bch2_trans_iter_init(trans, &alloc_iter, BTREE_ID_alloc,
323 bucket, BTREE_ITER_CACHED);
324 k = bch2_btree_iter_peek_slot(&alloc_iter);
329 if (k.k->type != KEY_TYPE_alloc_v4)
332 a = bkey_s_c_to_alloc_v4(k);
333 if (gen >= 0 && a.v->gen != gen)
336 for (i = 0; i < BCH_ALLOC_V4_NR_BACKPOINTERS(a.v); i++) {
337 if (alloc_v4_backpointers_c(a.v)[i].bucket_offset < *bp_offset)
340 *dst = alloc_v4_backpointers_c(a.v)[i];
341 *bp_offset = dst->bucket_offset;
345 for_each_btree_key_norestart(trans, bp_iter, BTREE_ID_backpointers,
347 if (bpos_ge(k.k->p, bp_end_pos))
350 if (k.k->type != KEY_TYPE_backpointer)
353 *dst = *bkey_s_c_to_backpointer(k).v;
354 *bp_offset = dst->bucket_offset + BACKPOINTER_OFFSET_MAX;
358 *bp_offset = U64_MAX;
360 bch2_trans_iter_exit(trans, &bp_iter);
361 bch2_trans_iter_exit(trans, &alloc_iter);
365 static void backpointer_not_found(struct btree_trans *trans,
368 struct bch_backpointer bp,
370 const char *thing_it_points_to)
372 struct bch_fs *c = trans->c;
373 struct printbuf buf = PRINTBUF;
375 if (likely(!bch2_backpointers_no_use_write_buffer))
378 prt_printf(&buf, "backpointer doesn't match %s it points to:\n ",
380 prt_printf(&buf, "bucket: ");
381 bch2_bpos_to_text(&buf, bucket);
382 prt_printf(&buf, "\n ");
384 if (bp_offset >= BACKPOINTER_OFFSET_MAX) {
386 bucket_pos_to_bp(c, bucket,
387 bp_offset - BACKPOINTER_OFFSET_MAX);
388 prt_printf(&buf, "backpointer pos: ");
389 bch2_bpos_to_text(&buf, bp_pos);
390 prt_printf(&buf, "\n ");
393 bch2_backpointer_to_text(&buf, &bp);
394 prt_printf(&buf, "\n ");
395 bch2_bkey_val_to_text(&buf, c, k);
396 if (!test_bit(BCH_FS_CHECK_BACKPOINTERS_DONE, &c->flags))
397 bch_err_ratelimited(c, "%s", buf.buf);
399 bch2_trans_inconsistent(trans, "%s", buf.buf);
404 struct bkey_s_c bch2_backpointer_get_key(struct btree_trans *trans,
405 struct btree_iter *iter,
408 struct bch_backpointer bp)
410 struct bch_fs *c = trans->c;
413 bch2_trans_node_iter_init(trans, iter,
417 min(bp.level, c->btree_roots[bp.btree_id].level),
419 k = bch2_btree_iter_peek_slot(iter);
421 bch2_trans_iter_exit(trans, iter);
425 if (bp.level == c->btree_roots[bp.btree_id].level + 1)
426 k = bkey_i_to_s_c(&c->btree_roots[bp.btree_id].key);
428 if (k.k && extent_matches_bp(c, bp.btree_id, bp.level, k, bucket, bp))
431 bch2_trans_iter_exit(trans, iter);
433 if (unlikely(bch2_backpointers_no_use_write_buffer)) {
438 * If a backpointer for a btree node wasn't found, it may be
439 * because it was overwritten by a new btree node that hasn't
440 * been written out yet - backpointer_get_node() checks for
443 b = bch2_backpointer_get_node(trans, iter, bucket, bp_offset, bp);
444 if (!IS_ERR_OR_NULL(b))
445 return bkey_i_to_s_c(&b->key);
447 bch2_trans_iter_exit(trans, iter);
450 return bkey_s_c_err(PTR_ERR(b));
451 return bkey_s_c_null;
454 backpointer_not_found(trans, bucket, bp_offset, bp, k, "extent");
457 return bkey_s_c_null;
460 struct btree *bch2_backpointer_get_node(struct btree_trans *trans,
461 struct btree_iter *iter,
464 struct bch_backpointer bp)
466 struct bch_fs *c = trans->c;
471 bch2_trans_node_iter_init(trans, iter,
477 b = bch2_btree_iter_peek_node(iter);
481 if (b && extent_matches_bp(c, bp.btree_id, bp.level,
482 bkey_i_to_s_c(&b->key),
486 if (b && btree_node_will_make_reachable(b)) {
487 b = ERR_PTR(-BCH_ERR_backpointer_to_overwritten_btree_node);
489 backpointer_not_found(trans, bucket, bp_offset, bp,
490 bkey_i_to_s_c(&b->key), "btree node");
494 bch2_trans_iter_exit(trans, iter);
498 static int bch2_check_btree_backpointer(struct btree_trans *trans, struct btree_iter *bp_iter,
501 struct bch_fs *c = trans->c;
502 struct btree_iter alloc_iter = { NULL };
504 struct bkey_s_c alloc_k;
505 struct printbuf buf = PRINTBUF;
508 if (fsck_err_on(!bch2_dev_exists2(c, k.k->p.inode), c,
509 "backpointer for mising device:\n%s",
510 (bch2_bkey_val_to_text(&buf, c, k), buf.buf))) {
511 ret = bch2_btree_delete_at(trans, bp_iter, 0);
515 ca = bch_dev_bkey_exists(c, k.k->p.inode);
517 bch2_trans_iter_init(trans, &alloc_iter, BTREE_ID_alloc,
518 bp_pos_to_bucket(c, k.k->p), 0);
520 alloc_k = bch2_btree_iter_peek_slot(&alloc_iter);
521 ret = bkey_err(alloc_k);
525 if (fsck_err_on(alloc_k.k->type != KEY_TYPE_alloc_v4, c,
526 "backpointer for nonexistent alloc key: %llu:%llu:0\n%s",
527 alloc_iter.pos.inode, alloc_iter.pos.offset,
528 (bch2_bkey_val_to_text(&buf, c, alloc_k), buf.buf))) {
529 ret = bch2_btree_delete_at(trans, bp_iter, 0);
534 bch2_trans_iter_exit(trans, &alloc_iter);
539 /* verify that every backpointer has a corresponding alloc key */
540 int bch2_check_btree_backpointers(struct bch_fs *c)
542 struct btree_iter iter;
545 return bch2_trans_run(c,
546 for_each_btree_key_commit(&trans, iter,
547 BTREE_ID_backpointers, POS_MIN, 0, k,
548 NULL, NULL, BTREE_INSERT_LAZY_RW|BTREE_INSERT_NOFAIL,
549 bch2_check_btree_backpointer(&trans, &iter, k)));
552 static int check_bp_exists(struct btree_trans *trans,
553 struct bpos bucket_pos,
554 struct bch_backpointer bp,
555 struct bkey_s_c orig_k,
556 struct bpos bucket_start,
557 struct bpos bucket_end,
558 struct bpos *last_flushed_pos)
560 struct bch_fs *c = trans->c;
561 struct btree_iter alloc_iter, bp_iter = { NULL };
562 struct printbuf buf = PRINTBUF;
563 struct bkey_s_c alloc_k, bp_k;
566 if (bpos_lt(bucket_pos, bucket_start) ||
567 bpos_gt(bucket_pos, bucket_end))
570 bch2_trans_iter_init(trans, &alloc_iter, BTREE_ID_alloc, bucket_pos, 0);
571 alloc_k = bch2_btree_iter_peek_slot(&alloc_iter);
572 ret = bkey_err(alloc_k);
576 if (alloc_k.k->type == KEY_TYPE_alloc_v4) {
577 struct bkey_s_c_alloc_v4 a = bkey_s_c_to_alloc_v4(alloc_k);
578 const struct bch_backpointer *bps = alloc_v4_backpointers_c(a.v);
579 unsigned i, nr = BCH_ALLOC_V4_NR_BACKPOINTERS(a.v);
581 for (i = 0; i < nr; i++) {
582 int cmp = backpointer_cmp(bps[i], bp) ?:
583 memcmp(&bps[i], &bp, sizeof(bp));
593 bch2_trans_iter_init(trans, &bp_iter, BTREE_ID_backpointers,
594 bucket_pos_to_bp(c, bucket_pos, bp.bucket_offset),
596 bp_k = bch2_btree_iter_peek_slot(&bp_iter);
597 ret = bkey_err(bp_k);
601 if (bp_k.k->type != KEY_TYPE_backpointer ||
602 memcmp(bkey_s_c_to_backpointer(bp_k).v, &bp, sizeof(bp))) {
603 if (!bpos_eq(*last_flushed_pos, orig_k.k->p)) {
604 *last_flushed_pos = orig_k.k->p;
605 ret = bch2_btree_write_buffer_flush_sync(trans) ?:
606 -BCH_ERR_transaction_restart_write_buffer_flush;
614 bch2_trans_iter_exit(trans, &bp_iter);
615 bch2_trans_iter_exit(trans, &alloc_iter);
620 prt_printf(&buf, "missing backpointer for btree=%s l=%u ",
621 bch2_btree_ids[bp.btree_id], bp.level);
622 bch2_bkey_val_to_text(&buf, c, orig_k);
623 prt_printf(&buf, "\nbp pos ");
624 bch2_bpos_to_text(&buf, bp_iter.pos);
626 if (c->sb.version < bcachefs_metadata_version_backpointers ||
627 c->opts.reconstruct_alloc ||
628 fsck_err(c, "%s", buf.buf)) {
629 struct bkey_i_alloc_v4 *a = bch2_alloc_to_v4_mut(trans, alloc_k);
631 ret = PTR_ERR_OR_ZERO(a) ?:
632 bch2_bucket_backpointer_mod(trans, a, bp, orig_k, true);
638 static int check_extent_to_backpointers(struct btree_trans *trans,
639 struct btree_iter *iter,
640 struct bpos bucket_start,
641 struct bpos bucket_end,
642 struct bpos *last_flushed_pos)
644 struct bch_fs *c = trans->c;
645 struct bkey_ptrs_c ptrs;
646 const union bch_extent_entry *entry;
647 struct extent_ptr_decoded p;
651 k = bch2_btree_iter_peek_all_levels(iter);
658 ptrs = bch2_bkey_ptrs_c(k);
659 bkey_for_each_ptr_decode(k.k, ptrs, p, entry) {
660 struct bpos bucket_pos;
661 struct bch_backpointer bp;
666 bch2_extent_ptr_to_bp(c, iter->btree_id, iter->path->level,
667 k, p, &bucket_pos, &bp);
669 ret = check_bp_exists(trans, bucket_pos, bp, k,
670 bucket_start, bucket_end,
679 static int check_btree_root_to_backpointers(struct btree_trans *trans,
680 enum btree_id btree_id,
681 struct bpos bucket_start,
682 struct bpos bucket_end,
683 struct bpos *last_flushed_pos)
685 struct bch_fs *c = trans->c;
686 struct btree_iter iter;
689 struct bkey_ptrs_c ptrs;
690 struct extent_ptr_decoded p;
691 const union bch_extent_entry *entry;
694 bch2_trans_node_iter_init(trans, &iter, btree_id, POS_MIN, 0,
695 c->btree_roots[btree_id].level, 0);
696 b = bch2_btree_iter_peek_node(&iter);
697 ret = PTR_ERR_OR_ZERO(b);
701 BUG_ON(b != btree_node_root(c, b));
703 k = bkey_i_to_s_c(&b->key);
704 ptrs = bch2_bkey_ptrs_c(k);
705 bkey_for_each_ptr_decode(k.k, ptrs, p, entry) {
706 struct bpos bucket_pos;
707 struct bch_backpointer bp;
712 bch2_extent_ptr_to_bp(c, iter.btree_id, iter.path->level + 1,
713 k, p, &bucket_pos, &bp);
715 ret = check_bp_exists(trans, bucket_pos, bp, k,
716 bucket_start, bucket_end,
722 bch2_trans_iter_exit(trans, &iter);
726 static inline struct bbpos bp_to_bbpos(struct bch_backpointer bp)
728 return (struct bbpos) {
729 .btree = bp.btree_id,
734 static size_t btree_nodes_fit_in_ram(struct bch_fs *c)
740 mem_bytes = i.totalram * i.mem_unit;
741 return div_u64(mem_bytes >> 1, btree_bytes(c));
744 int bch2_get_btree_in_memory_pos(struct btree_trans *trans,
745 unsigned btree_leaf_mask,
746 unsigned btree_interior_mask,
747 struct bbpos start, struct bbpos *end)
749 struct btree_iter iter;
751 size_t btree_nodes = btree_nodes_fit_in_ram(trans->c);
755 for (btree = start.btree; btree < BTREE_ID_NR && !ret; btree++) {
756 unsigned depth = ((1U << btree) & btree_leaf_mask) ? 1 : 2;
758 if (!((1U << btree) & btree_leaf_mask) &&
759 !((1U << btree) & btree_interior_mask))
762 bch2_trans_node_iter_init(trans, &iter, btree,
763 btree == start.btree ? start.pos : POS_MIN,
766 * for_each_btree_key_contineu() doesn't check the return value
767 * from bch2_btree_iter_advance(), which is needed when
768 * iterating over interior nodes where we'll see keys at
772 k = __bch2_btree_iter_peek_and_restart(trans, &iter, 0);
779 *end = BBPOS(btree, k.k->p);
780 bch2_trans_iter_exit(trans, &iter);
783 } while (bch2_btree_iter_advance(&iter));
784 bch2_trans_iter_exit(trans, &iter);
791 static int bch2_check_extents_to_backpointers_pass(struct btree_trans *trans,
792 struct bpos bucket_start,
793 struct bpos bucket_end)
795 struct btree_iter iter;
796 enum btree_id btree_id;
797 struct bpos last_flushed_pos = SPOS_MAX;
800 for (btree_id = 0; btree_id < BTREE_ID_NR; btree_id++) {
801 unsigned depth = btree_type_has_ptrs(btree_id) ? 0 : 1;
803 bch2_trans_node_iter_init(trans, &iter, btree_id, POS_MIN, 0,
805 BTREE_ITER_ALL_LEVELS|
806 BTREE_ITER_PREFETCH);
809 ret = commit_do(trans, NULL, NULL,
810 BTREE_INSERT_LAZY_RW|
812 check_extent_to_backpointers(trans, &iter,
813 bucket_start, bucket_end,
817 } while (!bch2_btree_iter_advance(&iter));
819 bch2_trans_iter_exit(trans, &iter);
824 ret = commit_do(trans, NULL, NULL,
825 BTREE_INSERT_LAZY_RW|
827 check_btree_root_to_backpointers(trans, btree_id,
828 bucket_start, bucket_end,
836 static struct bpos bucket_pos_to_bp_safe(const struct bch_fs *c,
839 return bch2_dev_exists2(c, bucket.inode)
840 ? bucket_pos_to_bp(c, bucket, 0)
844 int bch2_get_alloc_in_memory_pos(struct btree_trans *trans,
845 struct bpos start, struct bpos *end)
847 struct btree_iter alloc_iter;
848 struct btree_iter bp_iter;
849 struct bkey_s_c alloc_k, bp_k;
850 size_t btree_nodes = btree_nodes_fit_in_ram(trans->c);
851 bool alloc_end = false, bp_end = false;
854 bch2_trans_node_iter_init(trans, &alloc_iter, BTREE_ID_alloc,
856 bch2_trans_node_iter_init(trans, &bp_iter, BTREE_ID_backpointers,
857 bucket_pos_to_bp_safe(trans->c, start), 0, 1, 0);
860 ? __bch2_btree_iter_peek_and_restart(trans, &alloc_iter, 0)
863 ? __bch2_btree_iter_peek_and_restart(trans, &bp_iter, 0)
866 ret = bkey_err(alloc_k) ?: bkey_err(bp_k);
867 if ((!alloc_k.k && !bp_k.k) || ret) {
878 if (bpos_lt(alloc_iter.pos, SPOS_MAX) &&
879 bpos_lt(bucket_pos_to_bp_safe(trans->c, alloc_iter.pos), bp_iter.pos)) {
880 if (!bch2_btree_iter_advance(&alloc_iter))
883 if (!bch2_btree_iter_advance(&bp_iter))
887 bch2_trans_iter_exit(trans, &bp_iter);
888 bch2_trans_iter_exit(trans, &alloc_iter);
892 int bch2_check_extents_to_backpointers(struct bch_fs *c)
894 struct btree_trans trans;
895 struct bpos start = POS_MIN, end;
898 bch2_trans_init(&trans, c, 0, 0);
900 ret = bch2_get_alloc_in_memory_pos(&trans, start, &end);
904 if (bpos_eq(start, POS_MIN) && !bpos_eq(end, SPOS_MAX))
905 bch_verbose(c, "%s(): alloc info does not fit in ram, running in multiple passes with %zu nodes per pass",
906 __func__, btree_nodes_fit_in_ram(c));
908 if (!bpos_eq(start, POS_MIN) || !bpos_eq(end, SPOS_MAX)) {
909 struct printbuf buf = PRINTBUF;
911 prt_str(&buf, "check_extents_to_backpointers(): ");
912 bch2_bpos_to_text(&buf, start);
914 bch2_bpos_to_text(&buf, end);
916 bch_verbose(c, "%s", buf.buf);
920 ret = bch2_check_extents_to_backpointers_pass(&trans, start, end);
921 if (ret || bpos_eq(end, SPOS_MAX))
924 start = bpos_successor(end);
926 bch2_trans_exit(&trans);
931 static int check_one_backpointer(struct btree_trans *trans,
936 struct bpos *last_flushed_pos)
938 struct bch_fs *c = trans->c;
939 struct btree_iter iter;
940 struct bch_backpointer bp;
944 struct printbuf buf = PRINTBUF;
947 ret = bch2_get_next_backpointer(trans, bucket, -1, bp_offset, &bp, 0);
948 if (ret || *bp_offset == U64_MAX)
951 pos = bp_to_bbpos(bp);
952 if (bbpos_cmp(pos, start) < 0 ||
953 bbpos_cmp(pos, end) > 0)
956 k = bch2_backpointer_get_key(trans, &iter, bucket, *bp_offset, bp);
958 if (ret == -BCH_ERR_backpointer_to_overwritten_btree_node)
963 bp_pos = bucket_pos_to_bp(c, bucket,
964 max(*bp_offset, BACKPOINTER_OFFSET_MAX) - BACKPOINTER_OFFSET_MAX);
966 if (!k.k && !bpos_eq(*last_flushed_pos, bp_pos)) {
967 *last_flushed_pos = bp_pos;
968 pr_info("flushing at %llu:%llu",
969 last_flushed_pos->inode,
970 last_flushed_pos->offset);
972 ret = bch2_btree_write_buffer_flush_sync(trans) ?:
973 -BCH_ERR_transaction_restart_write_buffer_flush;
977 if (fsck_err_on(!k.k, c,
978 "%s backpointer points to missing extent\n%s",
979 *bp_offset < BACKPOINTER_OFFSET_MAX ? "alloc" : "btree",
980 (bch2_backpointer_to_text(&buf, &bp), buf.buf))) {
981 ret = bch2_backpointer_del_by_offset(trans, bucket, *bp_offset, bp);
983 bch_err(c, "backpointer at %llu not found", *bp_offset);
987 bch2_trans_iter_exit(trans, &iter);
992 static int bch2_check_backpointers_to_extents_pass(struct btree_trans *trans,
996 struct btree_iter iter;
998 struct bpos last_flushed_pos = SPOS_MAX;
1001 for_each_btree_key(trans, iter, BTREE_ID_alloc, POS_MIN,
1002 BTREE_ITER_PREFETCH, k, ret) {
1005 while (!(ret = commit_do(trans, NULL, NULL,
1006 BTREE_INSERT_LAZY_RW|
1007 BTREE_INSERT_NOFAIL,
1008 check_one_backpointer(trans, iter.pos, &bp_offset,
1009 start, end, &last_flushed_pos))) &&
1010 bp_offset < U64_MAX)
1016 bch2_trans_iter_exit(trans, &iter);
1017 return ret < 0 ? ret : 0;
1020 int bch2_check_backpointers_to_extents(struct bch_fs *c)
1022 struct btree_trans trans;
1023 struct bbpos start = (struct bbpos) { .btree = 0, .pos = POS_MIN, }, end;
1026 bch2_trans_init(&trans, c, 0, 0);
1028 ret = bch2_get_btree_in_memory_pos(&trans,
1029 (1U << BTREE_ID_extents)|
1030 (1U << BTREE_ID_reflink),
1036 if (!bbpos_cmp(start, BBPOS_MIN) &&
1037 bbpos_cmp(end, BBPOS_MAX))
1038 bch_verbose(c, "%s(): extents do not fit in ram, running in multiple passes with %zu nodes per pass",
1039 __func__, btree_nodes_fit_in_ram(c));
1041 if (bbpos_cmp(start, BBPOS_MIN) ||
1042 bbpos_cmp(end, BBPOS_MAX)) {
1043 struct printbuf buf = PRINTBUF;
1045 prt_str(&buf, "check_backpointers_to_extents(): ");
1046 bch2_bbpos_to_text(&buf, start);
1048 bch2_bbpos_to_text(&buf, end);
1050 bch_verbose(c, "%s", buf.buf);
1051 printbuf_exit(&buf);
1054 ret = bch2_check_backpointers_to_extents_pass(&trans, start, end);
1055 if (ret || !bbpos_cmp(end, BBPOS_MAX))
1058 start = bbpos_successor(end);
1060 bch2_trans_exit(&trans);