1 // SPDX-License-Identifier: GPL-2.0
4 #include "bkey_methods.h"
6 #include "btree_cache.h"
7 #include "btree_iter.h"
8 #include "btree_journal_iter.h"
9 #include "btree_key_cache.h"
10 #include "btree_locking.h"
11 #include "btree_update.h"
16 #include "journal_io.h"
21 #include <linux/random.h>
22 #include <linux/prefetch.h>
24 static inline void btree_path_list_remove(struct btree_trans *, struct btree_path *);
25 static inline void btree_path_list_add(struct btree_trans *,
26 btree_path_idx_t, btree_path_idx_t);
28 static inline unsigned long btree_iter_ip_allocated(struct btree_iter *iter)
30 #ifdef TRACK_PATH_ALLOCATED
31 return iter->ip_allocated;
37 static btree_path_idx_t btree_path_alloc(struct btree_trans *, btree_path_idx_t);
38 static void bch2_trans_srcu_lock(struct btree_trans *);
40 static inline int __btree_path_cmp(const struct btree_path *l,
41 enum btree_id r_btree_id,
47 * Must match lock ordering as defined by __bch2_btree_node_lock:
49 return cmp_int(l->btree_id, r_btree_id) ?:
50 cmp_int((int) l->cached, (int) r_cached) ?:
51 bpos_cmp(l->pos, r_pos) ?:
52 -cmp_int(l->level, r_level);
55 static inline int btree_path_cmp(const struct btree_path *l,
56 const struct btree_path *r)
58 return __btree_path_cmp(l, r->btree_id, r->cached, r->pos, r->level);
61 static inline struct bpos bkey_successor(struct btree_iter *iter, struct bpos p)
63 /* Are we iterating over keys in all snapshots? */
64 if (iter->flags & BTREE_ITER_ALL_SNAPSHOTS) {
65 p = bpos_successor(p);
67 p = bpos_nosnap_successor(p);
68 p.snapshot = iter->snapshot;
74 static inline struct bpos bkey_predecessor(struct btree_iter *iter, struct bpos p)
76 /* Are we iterating over keys in all snapshots? */
77 if (iter->flags & BTREE_ITER_ALL_SNAPSHOTS) {
78 p = bpos_predecessor(p);
80 p = bpos_nosnap_predecessor(p);
81 p.snapshot = iter->snapshot;
87 static inline struct bpos btree_iter_search_key(struct btree_iter *iter)
89 struct bpos pos = iter->pos;
91 if ((iter->flags & BTREE_ITER_IS_EXTENTS) &&
92 !bkey_eq(pos, POS_MAX))
93 pos = bkey_successor(iter, pos);
97 static inline bool btree_path_pos_before_node(struct btree_path *path,
100 return bpos_lt(path->pos, b->data->min_key);
103 static inline bool btree_path_pos_after_node(struct btree_path *path,
106 return bpos_gt(path->pos, b->key.k.p);
109 static inline bool btree_path_pos_in_node(struct btree_path *path,
112 return path->btree_id == b->c.btree_id &&
113 !btree_path_pos_before_node(path, b) &&
114 !btree_path_pos_after_node(path, b);
117 /* Btree iterator: */
119 #ifdef CONFIG_BCACHEFS_DEBUG
121 static void bch2_btree_path_verify_cached(struct btree_trans *trans,
122 struct btree_path *path)
124 struct bkey_cached *ck;
125 bool locked = btree_node_locked(path, 0);
127 if (!bch2_btree_node_relock(trans, path, 0))
130 ck = (void *) path->l[0].b;
131 BUG_ON(ck->key.btree_id != path->btree_id ||
132 !bkey_eq(ck->key.pos, path->pos));
135 btree_node_unlock(trans, path, 0);
138 static void bch2_btree_path_verify_level(struct btree_trans *trans,
139 struct btree_path *path, unsigned level)
141 struct btree_path_level *l;
142 struct btree_node_iter tmp;
144 struct bkey_packed *p, *k;
145 struct printbuf buf1 = PRINTBUF;
146 struct printbuf buf2 = PRINTBUF;
147 struct printbuf buf3 = PRINTBUF;
150 if (!bch2_debug_check_iterators)
155 locked = btree_node_locked(path, level);
159 bch2_btree_path_verify_cached(trans, path);
163 if (!btree_path_node(path, level))
166 if (!bch2_btree_node_relock_notrace(trans, path, level))
169 BUG_ON(!btree_path_pos_in_node(path, l->b));
171 bch2_btree_node_iter_verify(&l->iter, l->b);
174 * For interior nodes, the iterator will have skipped past deleted keys:
177 ? bch2_btree_node_iter_prev(&tmp, l->b)
178 : bch2_btree_node_iter_prev_all(&tmp, l->b);
179 k = bch2_btree_node_iter_peek_all(&l->iter, l->b);
181 if (p && bkey_iter_pos_cmp(l->b, p, &path->pos) >= 0) {
186 if (k && bkey_iter_pos_cmp(l->b, k, &path->pos) < 0) {
192 btree_node_unlock(trans, path, level);
195 bch2_bpos_to_text(&buf1, path->pos);
198 struct bkey uk = bkey_unpack_key(l->b, p);
200 bch2_bkey_to_text(&buf2, &uk);
202 prt_printf(&buf2, "(none)");
206 struct bkey uk = bkey_unpack_key(l->b, k);
208 bch2_bkey_to_text(&buf3, &uk);
210 prt_printf(&buf3, "(none)");
213 panic("path should be %s key at level %u:\n"
217 msg, level, buf1.buf, buf2.buf, buf3.buf);
220 static void bch2_btree_path_verify(struct btree_trans *trans,
221 struct btree_path *path)
223 struct bch_fs *c = trans->c;
226 EBUG_ON(path->btree_id >= BTREE_ID_NR);
228 for (i = 0; i < (!path->cached ? BTREE_MAX_DEPTH : 1); i++) {
230 BUG_ON(!path->cached &&
231 bch2_btree_id_root(c, path->btree_id)->b->c.level > i);
235 bch2_btree_path_verify_level(trans, path, i);
238 bch2_btree_path_verify_locks(path);
241 void bch2_trans_verify_paths(struct btree_trans *trans)
243 struct btree_path *path;
246 trans_for_each_path(trans, path, iter)
247 bch2_btree_path_verify(trans, path);
250 static void bch2_btree_iter_verify(struct btree_iter *iter)
252 struct btree_trans *trans = iter->trans;
254 BUG_ON(iter->btree_id >= BTREE_ID_NR);
256 BUG_ON(!!(iter->flags & BTREE_ITER_CACHED) != btree_iter_path(trans, iter)->cached);
258 BUG_ON((iter->flags & BTREE_ITER_IS_EXTENTS) &&
259 (iter->flags & BTREE_ITER_ALL_SNAPSHOTS));
261 BUG_ON(!(iter->flags & __BTREE_ITER_ALL_SNAPSHOTS) &&
262 (iter->flags & BTREE_ITER_ALL_SNAPSHOTS) &&
263 !btree_type_has_snapshot_field(iter->btree_id));
265 if (iter->update_path)
266 bch2_btree_path_verify(trans, &trans->paths[iter->update_path]);
267 bch2_btree_path_verify(trans, btree_iter_path(trans, iter));
270 static void bch2_btree_iter_verify_entry_exit(struct btree_iter *iter)
272 BUG_ON((iter->flags & BTREE_ITER_FILTER_SNAPSHOTS) &&
273 !iter->pos.snapshot);
275 BUG_ON(!(iter->flags & BTREE_ITER_ALL_SNAPSHOTS) &&
276 iter->pos.snapshot != iter->snapshot);
278 BUG_ON(bkey_lt(iter->pos, bkey_start_pos(&iter->k)) ||
279 bkey_gt(iter->pos, iter->k.p));
282 static int bch2_btree_iter_verify_ret(struct btree_iter *iter, struct bkey_s_c k)
284 struct btree_trans *trans = iter->trans;
285 struct btree_iter copy;
286 struct bkey_s_c prev;
289 if (!bch2_debug_check_iterators)
292 if (!(iter->flags & BTREE_ITER_FILTER_SNAPSHOTS))
295 if (bkey_err(k) || !k.k)
298 BUG_ON(!bch2_snapshot_is_ancestor(trans->c,
302 bch2_trans_iter_init(trans, ©, iter->btree_id, iter->pos,
303 BTREE_ITER_NOPRESERVE|
304 BTREE_ITER_ALL_SNAPSHOTS);
305 prev = bch2_btree_iter_prev(©);
309 ret = bkey_err(prev);
313 if (bkey_eq(prev.k->p, k.k->p) &&
314 bch2_snapshot_is_ancestor(trans->c, iter->snapshot,
315 prev.k->p.snapshot) > 0) {
316 struct printbuf buf1 = PRINTBUF, buf2 = PRINTBUF;
318 bch2_bkey_to_text(&buf1, k.k);
319 bch2_bkey_to_text(&buf2, prev.k);
321 panic("iter snap %u\n"
328 bch2_trans_iter_exit(trans, ©);
332 void bch2_assert_pos_locked(struct btree_trans *trans, enum btree_id id,
333 struct bpos pos, bool key_cache)
335 struct btree_path *path;
336 struct trans_for_each_path_inorder_iter iter;
337 struct printbuf buf = PRINTBUF;
339 btree_trans_sort_paths(trans);
341 trans_for_each_path_inorder(trans, path, iter) {
342 int cmp = cmp_int(path->btree_id, id) ?:
343 cmp_int(path->cached, key_cache);
350 if (!btree_node_locked(path, 0) ||
351 !path->should_be_locked)
355 if (bkey_ge(pos, path->l[0].b->data->min_key) &&
356 bkey_le(pos, path->l[0].b->key.k.p))
359 if (bkey_eq(pos, path->pos))
364 bch2_dump_trans_paths_updates(trans);
365 bch2_bpos_to_text(&buf, pos);
367 panic("not locked: %s %s%s\n",
368 bch2_btree_id_str(id), buf.buf,
369 key_cache ? " cached" : "");
374 static inline void bch2_btree_path_verify_level(struct btree_trans *trans,
375 struct btree_path *path, unsigned l) {}
376 static inline void bch2_btree_path_verify(struct btree_trans *trans,
377 struct btree_path *path) {}
378 static inline void bch2_btree_iter_verify(struct btree_iter *iter) {}
379 static inline void bch2_btree_iter_verify_entry_exit(struct btree_iter *iter) {}
380 static inline int bch2_btree_iter_verify_ret(struct btree_iter *iter, struct bkey_s_c k) { return 0; }
384 /* Btree path: fixups after btree updates */
386 static void btree_node_iter_set_set_pos(struct btree_node_iter *iter,
389 struct bkey_packed *k)
391 struct btree_node_iter_set *set;
393 btree_node_iter_for_each(iter, set)
394 if (set->end == t->end_offset) {
395 set->k = __btree_node_key_to_offset(b, k);
396 bch2_btree_node_iter_sort(iter, b);
400 bch2_btree_node_iter_push(iter, b, k, btree_bkey_last(b, t));
403 static void __bch2_btree_path_fix_key_modified(struct btree_path *path,
405 struct bkey_packed *where)
407 struct btree_path_level *l = &path->l[b->c.level];
409 if (where != bch2_btree_node_iter_peek_all(&l->iter, l->b))
412 if (bkey_iter_pos_cmp(l->b, where, &path->pos) < 0)
413 bch2_btree_node_iter_advance(&l->iter, l->b);
416 void bch2_btree_path_fix_key_modified(struct btree_trans *trans,
418 struct bkey_packed *where)
420 struct btree_path *path;
423 trans_for_each_path_with_node(trans, b, path, i) {
424 __bch2_btree_path_fix_key_modified(path, b, where);
425 bch2_btree_path_verify_level(trans, path, b->c.level);
429 static void __bch2_btree_node_iter_fix(struct btree_path *path,
431 struct btree_node_iter *node_iter,
433 struct bkey_packed *where,
434 unsigned clobber_u64s,
437 const struct bkey_packed *end = btree_bkey_last(b, t);
438 struct btree_node_iter_set *set;
439 unsigned offset = __btree_node_key_to_offset(b, where);
440 int shift = new_u64s - clobber_u64s;
441 unsigned old_end = t->end_offset - shift;
442 unsigned orig_iter_pos = node_iter->data[0].k;
443 bool iter_current_key_modified =
444 orig_iter_pos >= offset &&
445 orig_iter_pos <= offset + clobber_u64s;
447 btree_node_iter_for_each(node_iter, set)
448 if (set->end == old_end)
451 /* didn't find the bset in the iterator - might have to readd it: */
453 bkey_iter_pos_cmp(b, where, &path->pos) >= 0) {
454 bch2_btree_node_iter_push(node_iter, b, where, end);
457 /* Iterator is after key that changed */
461 set->end = t->end_offset;
463 /* Iterator hasn't gotten to the key that changed yet: */
468 bkey_iter_pos_cmp(b, where, &path->pos) >= 0) {
470 } else if (set->k < offset + clobber_u64s) {
471 set->k = offset + new_u64s;
472 if (set->k == set->end)
473 bch2_btree_node_iter_set_drop(node_iter, set);
475 /* Iterator is after key that changed */
476 set->k = (int) set->k + shift;
480 bch2_btree_node_iter_sort(node_iter, b);
482 if (node_iter->data[0].k != orig_iter_pos)
483 iter_current_key_modified = true;
486 * When a new key is added, and the node iterator now points to that
487 * key, the iterator might have skipped past deleted keys that should
488 * come after the key the iterator now points to. We have to rewind to
489 * before those deleted keys - otherwise
490 * bch2_btree_node_iter_prev_all() breaks:
492 if (!bch2_btree_node_iter_end(node_iter) &&
493 iter_current_key_modified &&
495 struct bkey_packed *k, *k2, *p;
497 k = bch2_btree_node_iter_peek_all(node_iter, b);
499 for_each_bset(b, t) {
500 bool set_pos = false;
502 if (node_iter->data[0].end == t->end_offset)
505 k2 = bch2_btree_node_iter_bset_pos(node_iter, b, t);
507 while ((p = bch2_bkey_prev_all(b, t, k2)) &&
508 bkey_iter_cmp(b, k, p) < 0) {
514 btree_node_iter_set_set_pos(node_iter,
520 void bch2_btree_node_iter_fix(struct btree_trans *trans,
521 struct btree_path *path,
523 struct btree_node_iter *node_iter,
524 struct bkey_packed *where,
525 unsigned clobber_u64s,
528 struct bset_tree *t = bch2_bkey_to_bset_inlined(b, where);
529 struct btree_path *linked;
532 if (node_iter != &path->l[b->c.level].iter) {
533 __bch2_btree_node_iter_fix(path, b, node_iter, t,
534 where, clobber_u64s, new_u64s);
536 if (bch2_debug_check_iterators)
537 bch2_btree_node_iter_verify(node_iter, b);
540 trans_for_each_path_with_node(trans, b, linked, i) {
541 __bch2_btree_node_iter_fix(linked, b,
542 &linked->l[b->c.level].iter, t,
543 where, clobber_u64s, new_u64s);
544 bch2_btree_path_verify_level(trans, linked, b->c.level);
548 /* Btree path level: pointer to a particular btree node and node iter */
550 static inline struct bkey_s_c __btree_iter_unpack(struct bch_fs *c,
551 struct btree_path_level *l,
553 struct bkey_packed *k)
557 * signal to bch2_btree_iter_peek_slot() that we're currently at
560 u->type = KEY_TYPE_deleted;
561 return bkey_s_c_null;
564 return bkey_disassemble(l->b, k, u);
567 static inline struct bkey_s_c btree_path_level_peek_all(struct bch_fs *c,
568 struct btree_path_level *l,
571 return __btree_iter_unpack(c, l, u,
572 bch2_btree_node_iter_peek_all(&l->iter, l->b));
575 static inline struct bkey_s_c btree_path_level_peek(struct btree_trans *trans,
576 struct btree_path *path,
577 struct btree_path_level *l,
580 struct bkey_s_c k = __btree_iter_unpack(trans->c, l, u,
581 bch2_btree_node_iter_peek(&l->iter, l->b));
583 path->pos = k.k ? k.k->p : l->b->key.k.p;
584 trans->paths_sorted = false;
585 bch2_btree_path_verify_level(trans, path, l - path->l);
589 static inline struct bkey_s_c btree_path_level_prev(struct btree_trans *trans,
590 struct btree_path *path,
591 struct btree_path_level *l,
594 struct bkey_s_c k = __btree_iter_unpack(trans->c, l, u,
595 bch2_btree_node_iter_prev(&l->iter, l->b));
597 path->pos = k.k ? k.k->p : l->b->data->min_key;
598 trans->paths_sorted = false;
599 bch2_btree_path_verify_level(trans, path, l - path->l);
603 static inline bool btree_path_advance_to_pos(struct btree_path *path,
604 struct btree_path_level *l,
607 struct bkey_packed *k;
610 while ((k = bch2_btree_node_iter_peek_all(&l->iter, l->b)) &&
611 bkey_iter_pos_cmp(l->b, k, &path->pos) < 0) {
612 if (max_advance > 0 && nr_advanced >= max_advance)
615 bch2_btree_node_iter_advance(&l->iter, l->b);
622 static inline void __btree_path_level_init(struct btree_path *path,
625 struct btree_path_level *l = &path->l[level];
627 bch2_btree_node_iter_init(&l->iter, l->b, &path->pos);
630 * Iterators to interior nodes should always be pointed at the first non
634 bch2_btree_node_iter_peek(&l->iter, l->b);
637 void bch2_btree_path_level_init(struct btree_trans *trans,
638 struct btree_path *path,
641 BUG_ON(path->cached);
643 EBUG_ON(!btree_path_pos_in_node(path, b));
645 path->l[b->c.level].lock_seq = six_lock_seq(&b->c.lock);
646 path->l[b->c.level].b = b;
647 __btree_path_level_init(path, b->c.level);
650 /* Btree path: fixups after btree node updates: */
652 static void bch2_trans_revalidate_updates_in_node(struct btree_trans *trans, struct btree *b)
654 struct bch_fs *c = trans->c;
656 trans_for_each_update(trans, i)
658 i->level == b->c.level &&
659 i->btree_id == b->c.btree_id &&
660 bpos_cmp(i->k->k.p, b->data->min_key) >= 0 &&
661 bpos_cmp(i->k->k.p, b->data->max_key) <= 0) {
662 i->old_v = bch2_btree_path_peek_slot(trans->paths + i->path, &i->old_k).v;
664 if (unlikely(trans->journal_replay_not_finished)) {
666 bch2_journal_keys_peek_slot(c, i->btree_id, i->level,
678 * A btree node is being replaced - update the iterator to point to the new
681 void bch2_trans_node_add(struct btree_trans *trans,
682 struct btree_path *path,
685 struct btree_path *prev;
687 BUG_ON(!btree_path_pos_in_node(path, b));
689 while ((prev = prev_btree_path(trans, path)) &&
690 btree_path_pos_in_node(prev, b))
694 path && btree_path_pos_in_node(path, b);
695 path = next_btree_path(trans, path))
696 if (path->uptodate == BTREE_ITER_UPTODATE && !path->cached) {
697 enum btree_node_locked_type t =
698 btree_lock_want(path, b->c.level);
700 if (t != BTREE_NODE_UNLOCKED) {
701 btree_node_unlock(trans, path, b->c.level);
702 six_lock_increment(&b->c.lock, (enum six_lock_type) t);
703 mark_btree_node_locked(trans, path, b->c.level, t);
706 bch2_btree_path_level_init(trans, path, b);
709 bch2_trans_revalidate_updates_in_node(trans, b);
713 * A btree node has been modified in such a way as to invalidate iterators - fix
716 void bch2_trans_node_reinit_iter(struct btree_trans *trans, struct btree *b)
718 struct btree_path *path;
721 trans_for_each_path_with_node(trans, b, path, i)
722 __btree_path_level_init(path, b->c.level);
724 bch2_trans_revalidate_updates_in_node(trans, b);
727 /* Btree path: traverse, set_pos: */
729 static inline int btree_path_lock_root(struct btree_trans *trans,
730 struct btree_path *path,
732 unsigned long trace_ip)
734 struct bch_fs *c = trans->c;
735 struct btree *b, **rootp = &bch2_btree_id_root(c, path->btree_id)->b;
736 enum six_lock_type lock_type;
740 EBUG_ON(path->nodes_locked);
743 b = READ_ONCE(*rootp);
744 path->level = READ_ONCE(b->c.level);
746 if (unlikely(path->level < depth_want)) {
748 * the root is at a lower depth than the depth we want:
749 * got to the end of the btree, or we're walking nodes
750 * greater than some depth and there are no nodes >=
753 path->level = depth_want;
754 for (i = path->level; i < BTREE_MAX_DEPTH; i++)
759 lock_type = __btree_lock_want(path, path->level);
760 ret = btree_node_lock(trans, path, &b->c,
761 path->level, lock_type, trace_ip);
763 if (bch2_err_matches(ret, BCH_ERR_lock_fail_root_changed))
765 if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
770 if (likely(b == READ_ONCE(*rootp) &&
771 b->c.level == path->level &&
773 for (i = 0; i < path->level; i++)
774 path->l[i].b = ERR_PTR(-BCH_ERR_no_btree_node_lock_root);
775 path->l[path->level].b = b;
776 for (i = path->level + 1; i < BTREE_MAX_DEPTH; i++)
779 mark_btree_node_locked(trans, path, path->level,
780 (enum btree_node_locked_type) lock_type);
781 bch2_btree_path_level_init(trans, path, b);
785 six_unlock_type(&b->c.lock, lock_type);
790 static int btree_path_prefetch(struct btree_trans *trans, struct btree_path *path)
792 struct bch_fs *c = trans->c;
793 struct btree_path_level *l = path_l(path);
794 struct btree_node_iter node_iter = l->iter;
795 struct bkey_packed *k;
797 unsigned nr = test_bit(BCH_FS_started, &c->flags)
798 ? (path->level > 1 ? 0 : 2)
799 : (path->level > 1 ? 1 : 16);
800 bool was_locked = btree_node_locked(path, path->level);
803 bch2_bkey_buf_init(&tmp);
805 while (nr-- && !ret) {
806 if (!bch2_btree_node_relock(trans, path, path->level))
809 bch2_btree_node_iter_advance(&node_iter, l->b);
810 k = bch2_btree_node_iter_peek(&node_iter, l->b);
814 bch2_bkey_buf_unpack(&tmp, c, l->b, k);
815 ret = bch2_btree_node_prefetch(trans, path, tmp.k, path->btree_id,
820 btree_node_unlock(trans, path, path->level);
822 bch2_bkey_buf_exit(&tmp, c);
826 static int btree_path_prefetch_j(struct btree_trans *trans, struct btree_path *path,
827 struct btree_and_journal_iter *jiter)
829 struct bch_fs *c = trans->c;
832 unsigned nr = test_bit(BCH_FS_started, &c->flags)
833 ? (path->level > 1 ? 0 : 2)
834 : (path->level > 1 ? 1 : 16);
835 bool was_locked = btree_node_locked(path, path->level);
838 bch2_bkey_buf_init(&tmp);
840 while (nr-- && !ret) {
841 if (!bch2_btree_node_relock(trans, path, path->level))
844 bch2_btree_and_journal_iter_advance(jiter);
845 k = bch2_btree_and_journal_iter_peek(jiter);
849 bch2_bkey_buf_reassemble(&tmp, c, k);
850 ret = bch2_btree_node_prefetch(trans, path, tmp.k, path->btree_id,
855 btree_node_unlock(trans, path, path->level);
857 bch2_bkey_buf_exit(&tmp, c);
861 static noinline void btree_node_mem_ptr_set(struct btree_trans *trans,
862 struct btree_path *path,
863 unsigned plevel, struct btree *b)
865 struct btree_path_level *l = &path->l[plevel];
866 bool locked = btree_node_locked(path, plevel);
867 struct bkey_packed *k;
868 struct bch_btree_ptr_v2 *bp;
870 if (!bch2_btree_node_relock(trans, path, plevel))
873 k = bch2_btree_node_iter_peek_all(&l->iter, l->b);
874 BUG_ON(k->type != KEY_TYPE_btree_ptr_v2);
876 bp = (void *) bkeyp_val(&l->b->format, k);
877 bp->mem_ptr = (unsigned long)b;
880 btree_node_unlock(trans, path, plevel);
883 static noinline int btree_node_iter_and_journal_peek(struct btree_trans *trans,
884 struct btree_path *path,
886 struct bkey_buf *out)
888 struct bch_fs *c = trans->c;
889 struct btree_path_level *l = path_l(path);
890 struct btree_and_journal_iter jiter;
894 __bch2_btree_and_journal_iter_init_node_iter(&jiter, c, l->b, l->iter, path->pos);
896 k = bch2_btree_and_journal_iter_peek(&jiter);
898 bch2_bkey_buf_reassemble(out, c, k);
900 if (flags & BTREE_ITER_PREFETCH)
901 ret = btree_path_prefetch_j(trans, path, &jiter);
903 bch2_btree_and_journal_iter_exit(&jiter);
907 static __always_inline int btree_path_down(struct btree_trans *trans,
908 struct btree_path *path,
910 unsigned long trace_ip)
912 struct bch_fs *c = trans->c;
913 struct btree_path_level *l = path_l(path);
915 unsigned level = path->level - 1;
916 enum six_lock_type lock_type = __btree_lock_want(path, level);
920 EBUG_ON(!btree_node_locked(path, path->level));
922 bch2_bkey_buf_init(&tmp);
924 if (unlikely(trans->journal_replay_not_finished)) {
925 ret = btree_node_iter_and_journal_peek(trans, path, flags, &tmp);
929 bch2_bkey_buf_unpack(&tmp, c, l->b,
930 bch2_btree_node_iter_peek(&l->iter, l->b));
932 if (flags & BTREE_ITER_PREFETCH) {
933 ret = btree_path_prefetch(trans, path);
939 b = bch2_btree_node_get(trans, path, tmp.k, level, lock_type, trace_ip);
940 ret = PTR_ERR_OR_ZERO(b);
944 if (likely(!trans->journal_replay_not_finished &&
945 tmp.k->k.type == KEY_TYPE_btree_ptr_v2) &&
946 unlikely(b != btree_node_mem_ptr(tmp.k)))
947 btree_node_mem_ptr_set(trans, path, level + 1, b);
949 if (btree_node_read_locked(path, level + 1))
950 btree_node_unlock(trans, path, level + 1);
952 mark_btree_node_locked(trans, path, level,
953 (enum btree_node_locked_type) lock_type);
955 bch2_btree_path_level_init(trans, path, b);
957 bch2_btree_path_verify_locks(path);
959 bch2_bkey_buf_exit(&tmp, c);
964 static int bch2_btree_path_traverse_all(struct btree_trans *trans)
966 struct bch_fs *c = trans->c;
967 struct btree_path *path;
968 unsigned long trace_ip = _RET_IP_;
972 if (trans->in_traverse_all)
973 return -BCH_ERR_transaction_restart_in_traverse_all;
975 trans->in_traverse_all = true;
977 trans->restarted = 0;
978 trans->last_restarted_ip = 0;
980 trans_for_each_path(trans, path, i)
981 path->should_be_locked = false;
983 btree_trans_sort_paths(trans);
985 bch2_trans_unlock(trans);
988 if (unlikely(trans->memory_allocation_failure)) {
991 closure_init_stack(&cl);
994 ret = bch2_btree_cache_cannibalize_lock(trans, &cl);
999 /* Now, redo traversals in correct order: */
1001 while (i < trans->nr_sorted) {
1002 btree_path_idx_t idx = trans->sorted[i];
1005 * Traversing a path can cause another path to be added at about
1006 * the same position:
1008 if (trans->paths[idx].uptodate) {
1009 __btree_path_get(&trans->paths[idx], false);
1010 ret = bch2_btree_path_traverse_one(trans, idx, 0, _THIS_IP_);
1011 __btree_path_put(&trans->paths[idx], false);
1013 if (bch2_err_matches(ret, BCH_ERR_transaction_restart) ||
1014 bch2_err_matches(ret, ENOMEM))
1024 * We used to assert that all paths had been traversed here
1025 * (path->uptodate < BTREE_ITER_NEED_TRAVERSE); however, since
1026 * path->should_be_locked is not set yet, we might have unlocked and
1027 * then failed to relock a path - that's fine.
1030 bch2_btree_cache_cannibalize_unlock(trans);
1032 trans->in_traverse_all = false;
1034 trace_and_count(c, trans_traverse_all, trans, trace_ip);
1038 static inline bool btree_path_check_pos_in_node(struct btree_path *path,
1039 unsigned l, int check_pos)
1041 if (check_pos < 0 && btree_path_pos_before_node(path, path->l[l].b))
1043 if (check_pos > 0 && btree_path_pos_after_node(path, path->l[l].b))
1048 static inline bool btree_path_good_node(struct btree_trans *trans,
1049 struct btree_path *path,
1050 unsigned l, int check_pos)
1052 return is_btree_node(path, l) &&
1053 bch2_btree_node_relock(trans, path, l) &&
1054 btree_path_check_pos_in_node(path, l, check_pos);
1057 static void btree_path_set_level_down(struct btree_trans *trans,
1058 struct btree_path *path,
1063 path->level = new_level;
1065 for (l = path->level + 1; l < BTREE_MAX_DEPTH; l++)
1066 if (btree_lock_want(path, l) == BTREE_NODE_UNLOCKED)
1067 btree_node_unlock(trans, path, l);
1069 btree_path_set_dirty(path, BTREE_ITER_NEED_TRAVERSE);
1070 bch2_btree_path_verify(trans, path);
1073 static noinline unsigned __btree_path_up_until_good_node(struct btree_trans *trans,
1074 struct btree_path *path,
1077 unsigned i, l = path->level;
1079 while (btree_path_node(path, l) &&
1080 !btree_path_good_node(trans, path, l, check_pos))
1081 __btree_path_set_level_up(trans, path, l++);
1083 /* If we need intent locks, take them too: */
1085 i < path->locks_want && btree_path_node(path, i);
1087 if (!bch2_btree_node_relock(trans, path, i)) {
1089 __btree_path_set_level_up(trans, path, l++);
1096 static inline unsigned btree_path_up_until_good_node(struct btree_trans *trans,
1097 struct btree_path *path,
1100 return likely(btree_node_locked(path, path->level) &&
1101 btree_path_check_pos_in_node(path, path->level, check_pos))
1103 : __btree_path_up_until_good_node(trans, path, check_pos);
1107 * This is the main state machine for walking down the btree - walks down to a
1110 * Returns 0 on success, -EIO on error (error reading in a btree node).
1112 * On error, caller (peek_node()/peek_key()) must return NULL; the error is
1113 * stashed in the iterator and returned from bch2_trans_exit().
1115 int bch2_btree_path_traverse_one(struct btree_trans *trans,
1116 btree_path_idx_t path_idx,
1118 unsigned long trace_ip)
1120 struct btree_path *path = &trans->paths[path_idx];
1121 unsigned depth_want = path->level;
1122 int ret = -((int) trans->restarted);
1127 if (unlikely(!trans->srcu_held))
1128 bch2_trans_srcu_lock(trans);
1131 * Ensure we obey path->should_be_locked: if it's set, we can't unlock
1132 * and re-traverse the path without a transaction restart:
1134 if (path->should_be_locked) {
1135 ret = bch2_btree_path_relock(trans, path, trace_ip);
1140 ret = bch2_btree_path_traverse_cached(trans, path, flags);
1144 path = &trans->paths[path_idx];
1146 if (unlikely(path->level >= BTREE_MAX_DEPTH))
1149 path->level = btree_path_up_until_good_node(trans, path, 0);
1151 EBUG_ON(btree_path_node(path, path->level) &&
1152 !btree_node_locked(path, path->level));
1155 * Note: path->nodes[path->level] may be temporarily NULL here - that
1156 * would indicate to other code that we got to the end of the btree,
1157 * here it indicates that relocking the root failed - it's critical that
1158 * btree_path_lock_root() comes next and that it can't fail
1160 while (path->level > depth_want) {
1161 ret = btree_path_node(path, path->level)
1162 ? btree_path_down(trans, path, flags, trace_ip)
1163 : btree_path_lock_root(trans, path, depth_want, trace_ip);
1164 if (unlikely(ret)) {
1167 * No nodes at this level - got to the end of
1174 __bch2_btree_path_unlock(trans, path);
1175 path->level = depth_want;
1176 path->l[path->level].b = ERR_PTR(ret);
1181 path->uptodate = BTREE_ITER_UPTODATE;
1183 if (bch2_err_matches(ret, BCH_ERR_transaction_restart) != !!trans->restarted)
1184 panic("ret %s (%i) trans->restarted %s (%i)\n",
1185 bch2_err_str(ret), ret,
1186 bch2_err_str(trans->restarted), trans->restarted);
1187 bch2_btree_path_verify(trans, path);
1191 static inline void btree_path_copy(struct btree_trans *trans, struct btree_path *dst,
1192 struct btree_path *src)
1194 unsigned i, offset = offsetof(struct btree_path, pos);
1196 memcpy((void *) dst + offset,
1197 (void *) src + offset,
1198 sizeof(struct btree_path) - offset);
1200 for (i = 0; i < BTREE_MAX_DEPTH; i++) {
1201 unsigned t = btree_node_locked_type(dst, i);
1203 if (t != BTREE_NODE_UNLOCKED)
1204 six_lock_increment(&dst->l[i].b->c.lock, t);
1208 static btree_path_idx_t btree_path_clone(struct btree_trans *trans, btree_path_idx_t src,
1211 btree_path_idx_t new = btree_path_alloc(trans, src);
1213 btree_path_copy(trans, trans->paths + new, trans->paths + src);
1214 __btree_path_get(trans->paths + new, intent);
1219 btree_path_idx_t __bch2_btree_path_make_mut(struct btree_trans *trans,
1220 btree_path_idx_t path, bool intent, unsigned long ip)
1222 __btree_path_put(trans->paths + path, intent);
1223 path = btree_path_clone(trans, path, intent);
1224 trans->paths[path].preserve = false;
1228 btree_path_idx_t __must_check
1229 __bch2_btree_path_set_pos(struct btree_trans *trans,
1230 btree_path_idx_t path_idx, struct bpos new_pos,
1231 bool intent, unsigned long ip)
1233 int cmp = bpos_cmp(new_pos, trans->paths[path_idx].pos);
1235 bch2_trans_verify_not_in_restart(trans);
1236 EBUG_ON(!trans->paths[path_idx].ref);
1238 path_idx = bch2_btree_path_make_mut(trans, path_idx, intent, ip);
1240 struct btree_path *path = trans->paths + path_idx;
1241 path->pos = new_pos;
1242 trans->paths_sorted = false;
1244 if (unlikely(path->cached)) {
1245 btree_node_unlock(trans, path, 0);
1246 path->l[0].b = ERR_PTR(-BCH_ERR_no_btree_node_up);
1247 btree_path_set_dirty(path, BTREE_ITER_NEED_TRAVERSE);
1251 unsigned level = btree_path_up_until_good_node(trans, path, cmp);
1253 if (btree_path_node(path, level)) {
1254 struct btree_path_level *l = &path->l[level];
1256 BUG_ON(!btree_node_locked(path, level));
1258 * We might have to skip over many keys, or just a few: try
1259 * advancing the node iterator, and if we have to skip over too
1260 * many keys just reinit it (or if we're rewinding, since that
1264 !btree_path_advance_to_pos(path, l, 8))
1265 bch2_btree_node_iter_init(&l->iter, l->b, &path->pos);
1268 * Iterators to interior nodes should always be pointed at the first non
1271 if (unlikely(level))
1272 bch2_btree_node_iter_peek(&l->iter, l->b);
1275 if (unlikely(level != path->level)) {
1276 btree_path_set_dirty(path, BTREE_ITER_NEED_TRAVERSE);
1277 __bch2_btree_path_unlock(trans, path);
1280 bch2_btree_path_verify(trans, path);
1284 /* Btree path: main interface: */
1286 static struct btree_path *have_path_at_pos(struct btree_trans *trans, struct btree_path *path)
1288 struct btree_path *sib;
1290 sib = prev_btree_path(trans, path);
1291 if (sib && !btree_path_cmp(sib, path))
1294 sib = next_btree_path(trans, path);
1295 if (sib && !btree_path_cmp(sib, path))
1301 static struct btree_path *have_node_at_pos(struct btree_trans *trans, struct btree_path *path)
1303 struct btree_path *sib;
1305 sib = prev_btree_path(trans, path);
1306 if (sib && sib->level == path->level && path_l(sib)->b == path_l(path)->b)
1309 sib = next_btree_path(trans, path);
1310 if (sib && sib->level == path->level && path_l(sib)->b == path_l(path)->b)
1316 static inline void __bch2_path_free(struct btree_trans *trans, btree_path_idx_t path)
1318 __bch2_btree_path_unlock(trans, trans->paths + path);
1319 btree_path_list_remove(trans, trans->paths + path);
1320 __clear_bit(path, trans->paths_allocated);
1323 void bch2_path_put(struct btree_trans *trans, btree_path_idx_t path_idx, bool intent)
1325 struct btree_path *path = trans->paths + path_idx, *dup;
1327 if (!__btree_path_put(path, intent))
1330 dup = path->preserve
1331 ? have_path_at_pos(trans, path)
1332 : have_node_at_pos(trans, path);
1334 if (!dup && !(!path->preserve && !is_btree_node(path, path->level)))
1337 if (path->should_be_locked &&
1338 !trans->restarted &&
1339 (!dup || !bch2_btree_path_relock_norestart(trans, dup, _THIS_IP_)))
1343 dup->preserve |= path->preserve;
1344 dup->should_be_locked |= path->should_be_locked;
1347 __bch2_path_free(trans, path_idx);
1350 static void bch2_path_put_nokeep(struct btree_trans *trans, btree_path_idx_t path,
1353 if (!__btree_path_put(trans->paths + path, intent))
1356 __bch2_path_free(trans, path);
1359 void __noreturn bch2_trans_restart_error(struct btree_trans *trans, u32 restart_count)
1361 panic("trans->restart_count %u, should be %u, last restarted by %pS\n",
1362 trans->restart_count, restart_count,
1363 (void *) trans->last_begin_ip);
1366 void __noreturn bch2_trans_in_restart_error(struct btree_trans *trans)
1368 panic("in transaction restart: %s, last restarted by %pS\n",
1369 bch2_err_str(trans->restarted),
1370 (void *) trans->last_restarted_ip);
1374 void bch2_trans_updates_to_text(struct printbuf *buf, struct btree_trans *trans)
1376 prt_printf(buf, "transaction updates for %s journal seq %llu",
1377 trans->fn, trans->journal_res.seq);
1379 printbuf_indent_add(buf, 2);
1381 trans_for_each_update(trans, i) {
1382 struct bkey_s_c old = { &i->old_k, i->old_v };
1384 prt_printf(buf, "update: btree=%s cached=%u %pS",
1385 bch2_btree_id_str(i->btree_id),
1387 (void *) i->ip_allocated);
1390 prt_printf(buf, " old ");
1391 bch2_bkey_val_to_text(buf, trans->c, old);
1394 prt_printf(buf, " new ");
1395 bch2_bkey_val_to_text(buf, trans->c, bkey_i_to_s_c(i->k));
1399 for (struct jset_entry *e = trans->journal_entries;
1400 e != btree_trans_journal_entries_top(trans);
1401 e = vstruct_next(e))
1402 bch2_journal_entry_to_text(buf, trans->c, e);
1404 printbuf_indent_sub(buf, 2);
1408 void bch2_dump_trans_updates(struct btree_trans *trans)
1410 struct printbuf buf = PRINTBUF;
1412 bch2_trans_updates_to_text(&buf, trans);
1413 bch2_print_string_as_lines(KERN_ERR, buf.buf);
1414 printbuf_exit(&buf);
1417 static void bch2_btree_path_to_text(struct printbuf *out, struct btree_trans *trans, btree_path_idx_t path_idx)
1419 struct btree_path *path = trans->paths + path_idx;
1421 prt_printf(out, "path: idx %2u ref %u:%u %c %c btree=%s l=%u pos ",
1422 path_idx, path->ref, path->intent_ref,
1423 path->preserve ? 'P' : ' ',
1424 path->should_be_locked ? 'S' : ' ',
1425 bch2_btree_id_str(path->btree_id),
1427 bch2_bpos_to_text(out, path->pos);
1429 prt_printf(out, " locks %u", path->nodes_locked);
1430 #ifdef TRACK_PATH_ALLOCATED
1431 prt_printf(out, " %pS", (void *) path->ip_allocated);
1436 static noinline __cold
1437 void __bch2_trans_paths_to_text(struct printbuf *out, struct btree_trans *trans,
1440 struct trans_for_each_path_inorder_iter iter;
1443 btree_trans_sort_paths(trans);
1445 trans_for_each_path_idx_inorder(trans, iter)
1446 bch2_btree_path_to_text(out, trans, iter.path_idx);
1450 void bch2_trans_paths_to_text(struct printbuf *out, struct btree_trans *trans)
1452 __bch2_trans_paths_to_text(out, trans, false);
1455 static noinline __cold
1456 void __bch2_dump_trans_paths_updates(struct btree_trans *trans, bool nosort)
1458 struct printbuf buf = PRINTBUF;
1460 __bch2_trans_paths_to_text(&buf, trans, nosort);
1461 bch2_trans_updates_to_text(&buf, trans);
1463 bch2_print_string_as_lines(KERN_ERR, buf.buf);
1464 printbuf_exit(&buf);
1468 void bch2_dump_trans_paths_updates(struct btree_trans *trans)
1470 __bch2_dump_trans_paths_updates(trans, false);
1474 static void bch2_trans_update_max_paths(struct btree_trans *trans)
1476 struct btree_transaction_stats *s = btree_trans_stats(trans);
1477 struct printbuf buf = PRINTBUF;
1478 size_t nr = bitmap_weight(trans->paths_allocated, trans->nr_paths);
1483 bch2_trans_paths_to_text(&buf, trans);
1485 if (!buf.allocation_failure) {
1486 mutex_lock(&s->lock);
1487 if (nr > s->nr_max_paths) {
1488 s->nr_max_paths = nr;
1489 swap(s->max_paths_text, buf.buf);
1491 mutex_unlock(&s->lock);
1494 printbuf_exit(&buf);
1496 trans->nr_paths_max = nr;
1500 int __bch2_btree_trans_too_many_iters(struct btree_trans *trans)
1502 if (trace_trans_restart_too_many_iters_enabled()) {
1503 struct printbuf buf = PRINTBUF;
1505 bch2_trans_paths_to_text(&buf, trans);
1506 trace_trans_restart_too_many_iters(trans, _THIS_IP_, buf.buf);
1507 printbuf_exit(&buf);
1510 count_event(trans->c, trans_restart_too_many_iters);
1512 return btree_trans_restart(trans, BCH_ERR_transaction_restart_too_many_iters);
1515 static noinline void btree_paths_realloc(struct btree_trans *trans)
1517 unsigned nr = trans->nr_paths * 2;
1519 void *p = kzalloc(BITS_TO_LONGS(nr) * sizeof(unsigned long) +
1521 sizeof(struct btree_trans_paths) +
1522 nr * sizeof(struct btree_path) +
1523 nr * sizeof(struct btree_insert_entry), GFP_KERNEL|__GFP_NOFAIL);
1525 unsigned long *paths_allocated = p;
1526 p += BITS_TO_LONGS(nr) * sizeof(unsigned long);
1527 struct btree_path *paths = p;
1528 p += nr * sizeof(struct btree_path);
1531 struct btree_insert_entry *updates = p;
1533 *trans_paths_nr(paths) = nr;
1535 memcpy(paths_allocated, trans->paths_allocated, BITS_TO_LONGS(trans->nr_paths) * sizeof(unsigned long));
1536 memcpy(sorted, trans->sorted, trans->nr_sorted);
1537 memcpy(paths, trans->paths, trans->nr_paths * sizeof(struct btree_path));
1538 memcpy(updates, trans->updates, trans->nr_paths * sizeof(struct btree_path));
1540 unsigned long *old = trans->paths_allocated;
1542 rcu_assign_pointer(trans->paths_allocated, paths_allocated);
1543 rcu_assign_pointer(trans->sorted, sorted);
1544 rcu_assign_pointer(trans->paths, paths);
1545 rcu_assign_pointer(trans->updates, updates);
1547 trans->nr_paths = nr;
1549 if (old != trans->_paths_allocated)
1550 kfree_rcu_mightsleep(trans->paths_allocated);
1553 static inline btree_path_idx_t btree_path_alloc(struct btree_trans *trans,
1554 btree_path_idx_t pos)
1556 btree_path_idx_t idx = find_first_zero_bit(trans->paths_allocated, trans->nr_paths);
1558 if (unlikely(idx == trans->nr_paths))
1559 btree_paths_realloc(trans);
1562 * Do this before marking the new path as allocated, since it won't be
1565 if (unlikely(idx > trans->nr_paths_max))
1566 bch2_trans_update_max_paths(trans);
1568 __set_bit(idx, trans->paths_allocated);
1570 struct btree_path *path = &trans->paths[idx];
1572 path->intent_ref = 0;
1573 path->nodes_locked = 0;
1575 btree_path_list_add(trans, pos, idx);
1576 trans->paths_sorted = false;
1580 btree_path_idx_t bch2_path_get(struct btree_trans *trans,
1581 enum btree_id btree_id, struct bpos pos,
1582 unsigned locks_want, unsigned level,
1583 unsigned flags, unsigned long ip)
1585 struct btree_path *path;
1586 bool cached = flags & BTREE_ITER_CACHED;
1587 bool intent = flags & BTREE_ITER_INTENT;
1588 struct trans_for_each_path_inorder_iter iter;
1589 btree_path_idx_t path_pos = 0, path_idx;
1591 bch2_trans_verify_not_in_restart(trans);
1592 bch2_trans_verify_locks(trans);
1594 btree_trans_sort_paths(trans);
1596 trans_for_each_path_inorder(trans, path, iter) {
1597 if (__btree_path_cmp(path,
1604 path_pos = iter.path_idx;
1608 trans->paths[path_pos].cached == cached &&
1609 trans->paths[path_pos].btree_id == btree_id &&
1610 trans->paths[path_pos].level == level) {
1611 __btree_path_get(trans->paths + path_pos, intent);
1612 path_idx = bch2_btree_path_set_pos(trans, path_pos, pos, intent, ip);
1613 path = trans->paths + path_idx;
1615 path_idx = btree_path_alloc(trans, path_pos);
1616 path = trans->paths + path_idx;
1618 __btree_path_get(path, intent);
1620 path->btree_id = btree_id;
1621 path->cached = cached;
1622 path->uptodate = BTREE_ITER_NEED_TRAVERSE;
1623 path->should_be_locked = false;
1624 path->level = level;
1625 path->locks_want = locks_want;
1626 path->nodes_locked = 0;
1627 for (unsigned i = 0; i < ARRAY_SIZE(path->l); i++)
1628 path->l[i].b = ERR_PTR(-BCH_ERR_no_btree_node_init);
1629 #ifdef TRACK_PATH_ALLOCATED
1630 path->ip_allocated = ip;
1632 trans->paths_sorted = false;
1635 if (!(flags & BTREE_ITER_NOPRESERVE))
1636 path->preserve = true;
1638 if (path->intent_ref)
1639 locks_want = max(locks_want, level + 1);
1642 * If the path has locks_want greater than requested, we don't downgrade
1643 * it here - on transaction restart because btree node split needs to
1644 * upgrade locks, we might be putting/getting the iterator again.
1645 * Downgrading iterators only happens via bch2_trans_downgrade(), after
1646 * a successful transaction commit.
1649 locks_want = min(locks_want, BTREE_MAX_DEPTH);
1650 if (locks_want > path->locks_want)
1651 bch2_btree_path_upgrade_noupgrade_sibs(trans, path, locks_want, NULL);
1656 struct bkey_s_c bch2_btree_path_peek_slot(struct btree_path *path, struct bkey *u)
1659 struct btree_path_level *l = path_l(path);
1660 struct bkey_packed *_k;
1663 if (unlikely(!l->b))
1664 return bkey_s_c_null;
1666 EBUG_ON(path->uptodate != BTREE_ITER_UPTODATE);
1667 EBUG_ON(!btree_node_locked(path, path->level));
1669 if (!path->cached) {
1670 _k = bch2_btree_node_iter_peek_all(&l->iter, l->b);
1671 k = _k ? bkey_disassemble(l->b, _k, u) : bkey_s_c_null;
1673 EBUG_ON(k.k && bkey_deleted(k.k) && bpos_eq(k.k->p, path->pos));
1675 if (!k.k || !bpos_eq(path->pos, k.k->p))
1678 struct bkey_cached *ck = (void *) path->l[0].b;
1681 (path->btree_id != ck->key.btree_id ||
1682 !bkey_eq(path->pos, ck->key.pos)));
1683 if (!ck || !ck->valid)
1684 return bkey_s_c_null;
1687 k = bkey_i_to_s_c(ck->k);
1694 return (struct bkey_s_c) { u, NULL };
1697 /* Btree iterators: */
1700 __bch2_btree_iter_traverse(struct btree_iter *iter)
1702 return bch2_btree_path_traverse(iter->trans, iter->path, iter->flags);
1706 bch2_btree_iter_traverse(struct btree_iter *iter)
1708 struct btree_trans *trans = iter->trans;
1711 iter->path = bch2_btree_path_set_pos(trans, iter->path,
1712 btree_iter_search_key(iter),
1713 iter->flags & BTREE_ITER_INTENT,
1714 btree_iter_ip_allocated(iter));
1716 ret = bch2_btree_path_traverse(iter->trans, iter->path, iter->flags);
1720 btree_path_set_should_be_locked(trans->paths + iter->path);
1724 /* Iterate across nodes (leaf and interior nodes) */
1726 struct btree *bch2_btree_iter_peek_node(struct btree_iter *iter)
1728 struct btree_trans *trans = iter->trans;
1729 struct btree *b = NULL;
1732 EBUG_ON(trans->paths[iter->path].cached);
1733 bch2_btree_iter_verify(iter);
1735 ret = bch2_btree_path_traverse(trans, iter->path, iter->flags);
1739 struct btree_path *path = btree_iter_path(trans, iter);
1740 b = btree_path_node(path, path->level);
1744 BUG_ON(bpos_lt(b->key.k.p, iter->pos));
1746 bkey_init(&iter->k);
1747 iter->k.p = iter->pos = b->key.k.p;
1749 iter->path = bch2_btree_path_set_pos(trans, iter->path, b->key.k.p,
1750 iter->flags & BTREE_ITER_INTENT,
1751 btree_iter_ip_allocated(iter));
1752 btree_path_set_should_be_locked(btree_iter_path(trans, iter));
1754 bch2_btree_iter_verify_entry_exit(iter);
1755 bch2_btree_iter_verify(iter);
1763 struct btree *bch2_btree_iter_peek_node_and_restart(struct btree_iter *iter)
1767 while (b = bch2_btree_iter_peek_node(iter),
1768 bch2_err_matches(PTR_ERR_OR_ZERO(b), BCH_ERR_transaction_restart))
1769 bch2_trans_begin(iter->trans);
1774 struct btree *bch2_btree_iter_next_node(struct btree_iter *iter)
1776 struct btree_trans *trans = iter->trans;
1777 struct btree *b = NULL;
1780 EBUG_ON(trans->paths[iter->path].cached);
1781 bch2_trans_verify_not_in_restart(trans);
1782 bch2_btree_iter_verify(iter);
1784 struct btree_path *path = btree_iter_path(trans, iter);
1786 /* already at end? */
1787 if (!btree_path_node(path, path->level))
1791 if (!btree_path_node(path, path->level + 1)) {
1792 btree_path_set_level_up(trans, path);
1796 if (!bch2_btree_node_relock(trans, path, path->level + 1)) {
1797 __bch2_btree_path_unlock(trans, path);
1798 path->l[path->level].b = ERR_PTR(-BCH_ERR_no_btree_node_relock);
1799 path->l[path->level + 1].b = ERR_PTR(-BCH_ERR_no_btree_node_relock);
1800 btree_path_set_dirty(path, BTREE_ITER_NEED_TRAVERSE);
1801 trace_and_count(trans->c, trans_restart_relock_next_node, trans, _THIS_IP_, path);
1802 ret = btree_trans_restart(trans, BCH_ERR_transaction_restart_relock);
1806 b = btree_path_node(path, path->level + 1);
1808 if (bpos_eq(iter->pos, b->key.k.p)) {
1809 __btree_path_set_level_up(trans, path, path->level++);
1812 * Haven't gotten to the end of the parent node: go back down to
1813 * the next child node
1815 iter->path = bch2_btree_path_set_pos(trans, iter->path,
1816 bpos_successor(iter->pos),
1817 iter->flags & BTREE_ITER_INTENT,
1818 btree_iter_ip_allocated(iter));
1820 path = btree_iter_path(trans, iter);
1821 btree_path_set_level_down(trans, path, iter->min_depth);
1823 ret = bch2_btree_path_traverse(trans, iter->path, iter->flags);
1827 path = btree_iter_path(trans, iter);
1828 b = path->l[path->level].b;
1831 bkey_init(&iter->k);
1832 iter->k.p = iter->pos = b->key.k.p;
1834 iter->path = bch2_btree_path_set_pos(trans, iter->path, b->key.k.p,
1835 iter->flags & BTREE_ITER_INTENT,
1836 btree_iter_ip_allocated(iter));
1837 btree_path_set_should_be_locked(btree_iter_path(trans, iter));
1838 EBUG_ON(btree_iter_path(trans, iter)->uptodate);
1840 bch2_btree_iter_verify_entry_exit(iter);
1841 bch2_btree_iter_verify(iter);
1849 /* Iterate across keys (in leaf nodes only) */
1851 inline bool bch2_btree_iter_advance(struct btree_iter *iter)
1853 struct bpos pos = iter->k.p;
1854 bool ret = !(iter->flags & BTREE_ITER_ALL_SNAPSHOTS
1855 ? bpos_eq(pos, SPOS_MAX)
1856 : bkey_eq(pos, SPOS_MAX));
1858 if (ret && !(iter->flags & BTREE_ITER_IS_EXTENTS))
1859 pos = bkey_successor(iter, pos);
1860 bch2_btree_iter_set_pos(iter, pos);
1864 inline bool bch2_btree_iter_rewind(struct btree_iter *iter)
1866 struct bpos pos = bkey_start_pos(&iter->k);
1867 bool ret = !(iter->flags & BTREE_ITER_ALL_SNAPSHOTS
1868 ? bpos_eq(pos, POS_MIN)
1869 : bkey_eq(pos, POS_MIN));
1871 if (ret && !(iter->flags & BTREE_ITER_IS_EXTENTS))
1872 pos = bkey_predecessor(iter, pos);
1873 bch2_btree_iter_set_pos(iter, pos);
1878 struct bkey_i *__bch2_btree_trans_peek_updates(struct btree_iter *iter)
1880 struct btree_trans *trans = iter->trans;
1881 struct bkey_i *ret = NULL;
1883 trans_for_each_update(trans, i) {
1884 if (i->btree_id < iter->btree_id)
1886 if (i->btree_id > iter->btree_id)
1888 if (bpos_lt(i->k->k.p, btree_iter_path(trans, iter)->pos))
1890 if (i->key_cache_already_flushed)
1892 if (!ret || bpos_lt(i->k->k.p, ret->k.p))
1899 static inline struct bkey_i *btree_trans_peek_updates(struct btree_iter *iter)
1901 return iter->flags & BTREE_ITER_WITH_UPDATES
1902 ? __bch2_btree_trans_peek_updates(iter)
1906 static struct bkey_i *bch2_btree_journal_peek(struct btree_trans *trans,
1907 struct btree_iter *iter,
1908 struct bpos end_pos)
1910 struct btree_path *path = btree_iter_path(trans, iter);
1912 return bch2_journal_keys_peek_upto(trans->c, iter->btree_id,
1916 &iter->journal_idx);
1920 struct bkey_s_c btree_trans_peek_slot_journal(struct btree_trans *trans,
1921 struct btree_iter *iter)
1923 struct btree_path *path = btree_iter_path(trans, iter);
1924 struct bkey_i *k = bch2_btree_journal_peek(trans, iter, path->pos);
1928 return bkey_i_to_s_c(k);
1930 return bkey_s_c_null;
1935 struct bkey_s_c btree_trans_peek_journal(struct btree_trans *trans,
1936 struct btree_iter *iter,
1939 struct btree_path *path = btree_iter_path(trans, iter);
1940 struct bkey_i *next_journal =
1941 bch2_btree_journal_peek(trans, iter,
1942 k.k ? k.k->p : path_l(path)->b->key.k.p);
1945 iter->k = next_journal->k;
1946 k = bkey_i_to_s_c(next_journal);
1953 * Checks btree key cache for key at iter->pos and returns it if present, or
1957 struct bkey_s_c btree_trans_peek_key_cache(struct btree_iter *iter, struct bpos pos)
1959 struct btree_trans *trans = iter->trans;
1960 struct bch_fs *c = trans->c;
1965 if ((iter->flags & BTREE_ITER_KEY_CACHE_FILL) &&
1966 bpos_eq(iter->pos, pos))
1967 return bkey_s_c_null;
1969 if (!bch2_btree_key_cache_find(c, iter->btree_id, pos))
1970 return bkey_s_c_null;
1972 if (!iter->key_cache_path)
1973 iter->key_cache_path = bch2_path_get(trans, iter->btree_id, pos,
1974 iter->flags & BTREE_ITER_INTENT, 0,
1975 iter->flags|BTREE_ITER_CACHED|
1976 BTREE_ITER_CACHED_NOFILL,
1979 iter->key_cache_path = bch2_btree_path_set_pos(trans, iter->key_cache_path, pos,
1980 iter->flags & BTREE_ITER_INTENT,
1981 btree_iter_ip_allocated(iter));
1983 ret = bch2_btree_path_traverse(trans, iter->key_cache_path,
1984 iter->flags|BTREE_ITER_CACHED) ?:
1985 bch2_btree_path_relock(trans, btree_iter_path(trans, iter), _THIS_IP_);
1987 return bkey_s_c_err(ret);
1989 btree_path_set_should_be_locked(trans->paths + iter->key_cache_path);
1991 k = bch2_btree_path_peek_slot(trans->paths + iter->key_cache_path, &u);
1992 if (k.k && !bkey_err(k)) {
1999 static struct bkey_s_c __bch2_btree_iter_peek(struct btree_iter *iter, struct bpos search_key)
2001 struct btree_trans *trans = iter->trans;
2002 struct bkey_i *next_update;
2003 struct bkey_s_c k, k2;
2006 EBUG_ON(btree_iter_path(trans, iter)->cached);
2007 bch2_btree_iter_verify(iter);
2010 struct btree_path_level *l;
2012 iter->path = bch2_btree_path_set_pos(trans, iter->path, search_key,
2013 iter->flags & BTREE_ITER_INTENT,
2014 btree_iter_ip_allocated(iter));
2016 ret = bch2_btree_path_traverse(trans, iter->path, iter->flags);
2017 if (unlikely(ret)) {
2018 /* ensure that iter->k is consistent with iter->pos: */
2019 bch2_btree_iter_set_pos(iter, iter->pos);
2020 k = bkey_s_c_err(ret);
2024 struct btree_path *path = btree_iter_path(trans, iter);
2027 if (unlikely(!l->b)) {
2028 /* No btree nodes at requested level: */
2029 bch2_btree_iter_set_pos(iter, SPOS_MAX);
2034 btree_path_set_should_be_locked(path);
2036 k = btree_path_level_peek_all(trans->c, l, &iter->k);
2038 if (unlikely(iter->flags & BTREE_ITER_WITH_KEY_CACHE) &&
2040 (k2 = btree_trans_peek_key_cache(iter, k.k->p)).k) {
2044 bch2_btree_iter_set_pos(iter, iter->pos);
2049 if (unlikely(iter->flags & BTREE_ITER_WITH_JOURNAL))
2050 k = btree_trans_peek_journal(trans, iter, k);
2052 next_update = btree_trans_peek_updates(iter);
2055 bpos_le(next_update->k.p,
2056 k.k ? k.k->p : l->b->key.k.p)) {
2057 iter->k = next_update->k;
2058 k = bkey_i_to_s_c(next_update);
2061 if (k.k && bkey_deleted(k.k)) {
2063 * If we've got a whiteout, and it's after the search
2064 * key, advance the search key to the whiteout instead
2065 * of just after the whiteout - it might be a btree
2066 * whiteout, with a real key at the same position, since
2067 * in the btree deleted keys sort before non deleted.
2069 search_key = !bpos_eq(search_key, k.k->p)
2071 : bpos_successor(k.k->p);
2077 } else if (likely(!bpos_eq(l->b->key.k.p, SPOS_MAX))) {
2078 /* Advance to next leaf node: */
2079 search_key = bpos_successor(l->b->key.k.p);
2082 bch2_btree_iter_set_pos(iter, SPOS_MAX);
2088 bch2_btree_iter_verify(iter);
2094 * bch2_btree_iter_peek_upto() - returns first key greater than or equal to
2095 * iterator's current position
2096 * @iter: iterator to peek from
2097 * @end: search limit: returns keys less than or equal to @end
2099 * Returns: key if found, or an error extractable with bkey_err().
2101 struct bkey_s_c bch2_btree_iter_peek_upto(struct btree_iter *iter, struct bpos end)
2103 struct btree_trans *trans = iter->trans;
2104 struct bpos search_key = btree_iter_search_key(iter);
2106 struct bpos iter_pos;
2109 EBUG_ON((iter->flags & BTREE_ITER_FILTER_SNAPSHOTS) && bkey_eq(end, POS_MAX));
2111 if (iter->update_path) {
2112 bch2_path_put_nokeep(trans, iter->update_path,
2113 iter->flags & BTREE_ITER_INTENT);
2114 iter->update_path = 0;
2117 bch2_btree_iter_verify_entry_exit(iter);
2120 k = __bch2_btree_iter_peek(iter, search_key);
2123 if (unlikely(bkey_err(k)))
2127 * iter->pos should be mononotically increasing, and always be
2128 * equal to the key we just returned - except extents can
2129 * straddle iter->pos:
2131 if (!(iter->flags & BTREE_ITER_IS_EXTENTS))
2134 iter_pos = bkey_max(iter->pos, bkey_start_pos(k.k));
2136 if (unlikely(!(iter->flags & BTREE_ITER_IS_EXTENTS)
2137 ? bkey_gt(iter_pos, end)
2138 : bkey_ge(iter_pos, end)))
2141 if (iter->update_path &&
2142 !bkey_eq(trans->paths[iter->update_path].pos, k.k->p)) {
2143 bch2_path_put_nokeep(trans, iter->update_path,
2144 iter->flags & BTREE_ITER_INTENT);
2145 iter->update_path = 0;
2148 if ((iter->flags & BTREE_ITER_FILTER_SNAPSHOTS) &&
2149 (iter->flags & BTREE_ITER_INTENT) &&
2150 !(iter->flags & BTREE_ITER_IS_EXTENTS) &&
2151 !iter->update_path) {
2152 struct bpos pos = k.k->p;
2154 if (pos.snapshot < iter->snapshot) {
2155 search_key = bpos_successor(k.k->p);
2159 pos.snapshot = iter->snapshot;
2162 * advance, same as on exit for iter->path, but only up
2165 __btree_path_get(trans->paths + iter->path, iter->flags & BTREE_ITER_INTENT);
2166 iter->update_path = iter->path;
2168 iter->update_path = bch2_btree_path_set_pos(trans,
2169 iter->update_path, pos,
2170 iter->flags & BTREE_ITER_INTENT,
2172 ret = bch2_btree_path_traverse(trans, iter->update_path, iter->flags);
2173 if (unlikely(ret)) {
2174 k = bkey_s_c_err(ret);
2180 * We can never have a key in a leaf node at POS_MAX, so
2181 * we don't have to check these successor() calls:
2183 if ((iter->flags & BTREE_ITER_FILTER_SNAPSHOTS) &&
2184 !bch2_snapshot_is_ancestor(trans->c,
2187 search_key = bpos_successor(k.k->p);
2191 if (bkey_whiteout(k.k) &&
2192 !(iter->flags & BTREE_ITER_ALL_SNAPSHOTS)) {
2193 search_key = bkey_successor(iter, k.k->p);
2200 iter->pos = iter_pos;
2202 iter->path = bch2_btree_path_set_pos(trans, iter->path, k.k->p,
2203 iter->flags & BTREE_ITER_INTENT,
2204 btree_iter_ip_allocated(iter));
2206 btree_path_set_should_be_locked(btree_iter_path(trans, iter));
2208 if (iter->update_path) {
2209 ret = bch2_btree_path_relock(trans, trans->paths + iter->update_path, _THIS_IP_);
2211 k = bkey_s_c_err(ret);
2213 btree_path_set_should_be_locked(trans->paths + iter->update_path);
2216 if (!(iter->flags & BTREE_ITER_ALL_SNAPSHOTS))
2217 iter->pos.snapshot = iter->snapshot;
2219 ret = bch2_btree_iter_verify_ret(iter, k);
2220 if (unlikely(ret)) {
2221 bch2_btree_iter_set_pos(iter, iter->pos);
2222 k = bkey_s_c_err(ret);
2225 bch2_btree_iter_verify_entry_exit(iter);
2229 bch2_btree_iter_set_pos(iter, end);
2235 * bch2_btree_iter_next() - returns first key greater than iterator's current
2237 * @iter: iterator to peek from
2239 * Returns: key if found, or an error extractable with bkey_err().
2241 struct bkey_s_c bch2_btree_iter_next(struct btree_iter *iter)
2243 if (!bch2_btree_iter_advance(iter))
2244 return bkey_s_c_null;
2246 return bch2_btree_iter_peek(iter);
2250 * bch2_btree_iter_peek_prev() - returns first key less than or equal to
2251 * iterator's current position
2252 * @iter: iterator to peek from
2254 * Returns: key if found, or an error extractable with bkey_err().
2256 struct bkey_s_c bch2_btree_iter_peek_prev(struct btree_iter *iter)
2258 struct btree_trans *trans = iter->trans;
2259 struct bpos search_key = iter->pos;
2261 struct bkey saved_k;
2262 const struct bch_val *saved_v;
2263 btree_path_idx_t saved_path = 0;
2266 EBUG_ON(btree_iter_path(trans, iter)->cached ||
2267 btree_iter_path(trans, iter)->level);
2268 EBUG_ON(iter->flags & BTREE_ITER_WITH_UPDATES);
2270 if (iter->flags & BTREE_ITER_WITH_JOURNAL)
2271 return bkey_s_c_err(-EIO);
2273 bch2_btree_iter_verify(iter);
2274 bch2_btree_iter_verify_entry_exit(iter);
2276 if (iter->flags & BTREE_ITER_FILTER_SNAPSHOTS)
2277 search_key.snapshot = U32_MAX;
2280 iter->path = bch2_btree_path_set_pos(trans, iter->path, search_key,
2281 iter->flags & BTREE_ITER_INTENT,
2282 btree_iter_ip_allocated(iter));
2284 ret = bch2_btree_path_traverse(trans, iter->path, iter->flags);
2285 if (unlikely(ret)) {
2286 /* ensure that iter->k is consistent with iter->pos: */
2287 bch2_btree_iter_set_pos(iter, iter->pos);
2288 k = bkey_s_c_err(ret);
2292 struct btree_path *path = btree_iter_path(trans, iter);
2294 k = btree_path_level_peek(trans, path, &path->l[0], &iter->k);
2296 ((iter->flags & BTREE_ITER_IS_EXTENTS)
2297 ? bpos_ge(bkey_start_pos(k.k), search_key)
2298 : bpos_gt(k.k->p, search_key)))
2299 k = btree_path_level_prev(trans, path, &path->l[0], &iter->k);
2302 if (iter->flags & BTREE_ITER_FILTER_SNAPSHOTS) {
2303 if (k.k->p.snapshot == iter->snapshot)
2307 * If we have a saved candidate, and we're no
2308 * longer at the same _key_ (not pos), return
2311 if (saved_path && !bkey_eq(k.k->p, saved_k.p)) {
2312 bch2_path_put_nokeep(trans, iter->path,
2313 iter->flags & BTREE_ITER_INTENT);
2314 iter->path = saved_path;
2321 if (bch2_snapshot_is_ancestor(trans->c,
2325 bch2_path_put_nokeep(trans, saved_path,
2326 iter->flags & BTREE_ITER_INTENT);
2327 saved_path = btree_path_clone(trans, iter->path,
2328 iter->flags & BTREE_ITER_INTENT);
2329 path = btree_iter_path(trans, iter);
2334 search_key = bpos_predecessor(k.k->p);
2338 if (bkey_whiteout(k.k) &&
2339 !(iter->flags & BTREE_ITER_ALL_SNAPSHOTS)) {
2340 search_key = bkey_predecessor(iter, k.k->p);
2341 if (iter->flags & BTREE_ITER_FILTER_SNAPSHOTS)
2342 search_key.snapshot = U32_MAX;
2346 btree_path_set_should_be_locked(path);
2348 } else if (likely(!bpos_eq(path->l[0].b->data->min_key, POS_MIN))) {
2349 /* Advance to previous leaf node: */
2350 search_key = bpos_predecessor(path->l[0].b->data->min_key);
2352 /* Start of btree: */
2353 bch2_btree_iter_set_pos(iter, POS_MIN);
2359 EBUG_ON(bkey_gt(bkey_start_pos(k.k), iter->pos));
2361 /* Extents can straddle iter->pos: */
2362 if (bkey_lt(k.k->p, iter->pos))
2365 if (iter->flags & BTREE_ITER_FILTER_SNAPSHOTS)
2366 iter->pos.snapshot = iter->snapshot;
2369 bch2_path_put_nokeep(trans, saved_path, iter->flags & BTREE_ITER_INTENT);
2371 bch2_btree_iter_verify_entry_exit(iter);
2372 bch2_btree_iter_verify(iter);
2378 * bch2_btree_iter_prev() - returns first key less than iterator's current
2380 * @iter: iterator to peek from
2382 * Returns: key if found, or an error extractable with bkey_err().
2384 struct bkey_s_c bch2_btree_iter_prev(struct btree_iter *iter)
2386 if (!bch2_btree_iter_rewind(iter))
2387 return bkey_s_c_null;
2389 return bch2_btree_iter_peek_prev(iter);
2392 struct bkey_s_c bch2_btree_iter_peek_slot(struct btree_iter *iter)
2394 struct btree_trans *trans = iter->trans;
2395 struct bpos search_key;
2399 bch2_btree_iter_verify(iter);
2400 bch2_btree_iter_verify_entry_exit(iter);
2401 EBUG_ON(btree_iter_path(trans, iter)->level && (iter->flags & BTREE_ITER_WITH_KEY_CACHE));
2403 /* extents can't span inode numbers: */
2404 if ((iter->flags & BTREE_ITER_IS_EXTENTS) &&
2405 unlikely(iter->pos.offset == KEY_OFFSET_MAX)) {
2406 if (iter->pos.inode == KEY_INODE_MAX)
2407 return bkey_s_c_null;
2409 bch2_btree_iter_set_pos(iter, bpos_nosnap_successor(iter->pos));
2412 search_key = btree_iter_search_key(iter);
2413 iter->path = bch2_btree_path_set_pos(trans, iter->path, search_key,
2414 iter->flags & BTREE_ITER_INTENT,
2415 btree_iter_ip_allocated(iter));
2417 ret = bch2_btree_path_traverse(trans, iter->path, iter->flags);
2418 if (unlikely(ret)) {
2419 k = bkey_s_c_err(ret);
2423 if ((iter->flags & BTREE_ITER_CACHED) ||
2424 !(iter->flags & (BTREE_ITER_IS_EXTENTS|BTREE_ITER_FILTER_SNAPSHOTS))) {
2425 struct bkey_i *next_update;
2427 if ((next_update = btree_trans_peek_updates(iter)) &&
2428 bpos_eq(next_update->k.p, iter->pos)) {
2429 iter->k = next_update->k;
2430 k = bkey_i_to_s_c(next_update);
2434 if (unlikely(iter->flags & BTREE_ITER_WITH_JOURNAL) &&
2435 (k = btree_trans_peek_slot_journal(trans, iter)).k)
2438 if (unlikely(iter->flags & BTREE_ITER_WITH_KEY_CACHE) &&
2439 (k = btree_trans_peek_key_cache(iter, iter->pos)).k) {
2442 /* We're not returning a key from iter->path: */
2446 k = bch2_btree_path_peek_slot(trans->paths + iter->path, &iter->k);
2451 struct bpos end = iter->pos;
2453 if (iter->flags & BTREE_ITER_IS_EXTENTS)
2454 end.offset = U64_MAX;
2456 EBUG_ON(btree_iter_path(trans, iter)->level);
2458 if (iter->flags & BTREE_ITER_INTENT) {
2459 struct btree_iter iter2;
2461 bch2_trans_copy_iter(&iter2, iter);
2462 k = bch2_btree_iter_peek_upto(&iter2, end);
2464 if (k.k && !bkey_err(k)) {
2468 bch2_trans_iter_exit(trans, &iter2);
2470 struct bpos pos = iter->pos;
2472 k = bch2_btree_iter_peek_upto(iter, end);
2473 if (unlikely(bkey_err(k)))
2474 bch2_btree_iter_set_pos(iter, pos);
2479 if (unlikely(bkey_err(k)))
2482 next = k.k ? bkey_start_pos(k.k) : POS_MAX;
2484 if (bkey_lt(iter->pos, next)) {
2485 bkey_init(&iter->k);
2486 iter->k.p = iter->pos;
2488 if (iter->flags & BTREE_ITER_IS_EXTENTS) {
2489 bch2_key_resize(&iter->k,
2490 min_t(u64, KEY_SIZE_MAX,
2491 (next.inode == iter->pos.inode
2495 EBUG_ON(!iter->k.size);
2498 k = (struct bkey_s_c) { &iter->k, NULL };
2502 btree_path_set_should_be_locked(btree_iter_path(trans, iter));
2504 bch2_btree_iter_verify_entry_exit(iter);
2505 bch2_btree_iter_verify(iter);
2506 ret = bch2_btree_iter_verify_ret(iter, k);
2508 return bkey_s_c_err(ret);
2513 struct bkey_s_c bch2_btree_iter_next_slot(struct btree_iter *iter)
2515 if (!bch2_btree_iter_advance(iter))
2516 return bkey_s_c_null;
2518 return bch2_btree_iter_peek_slot(iter);
2521 struct bkey_s_c bch2_btree_iter_prev_slot(struct btree_iter *iter)
2523 if (!bch2_btree_iter_rewind(iter))
2524 return bkey_s_c_null;
2526 return bch2_btree_iter_peek_slot(iter);
2529 struct bkey_s_c bch2_btree_iter_peek_and_restart_outlined(struct btree_iter *iter)
2533 while (btree_trans_too_many_iters(iter->trans) ||
2534 (k = bch2_btree_iter_peek_type(iter, iter->flags),
2535 bch2_err_matches(bkey_err(k), BCH_ERR_transaction_restart)))
2536 bch2_trans_begin(iter->trans);
2541 /* new transactional stuff: */
2543 #ifdef CONFIG_BCACHEFS_DEBUG
2544 static void btree_trans_verify_sorted_refs(struct btree_trans *trans)
2546 struct btree_path *path;
2549 BUG_ON(trans->nr_sorted != bitmap_weight(trans->paths_allocated, trans->nr_paths) - 1);
2551 trans_for_each_path(trans, path, i) {
2552 BUG_ON(path->sorted_idx >= trans->nr_sorted);
2553 BUG_ON(trans->sorted[path->sorted_idx] != i);
2556 for (i = 0; i < trans->nr_sorted; i++) {
2557 unsigned idx = trans->sorted[i];
2559 BUG_ON(!test_bit(idx, trans->paths_allocated));
2560 BUG_ON(trans->paths[idx].sorted_idx != i);
2564 static void btree_trans_verify_sorted(struct btree_trans *trans)
2566 struct btree_path *path, *prev = NULL;
2567 struct trans_for_each_path_inorder_iter iter;
2569 if (!bch2_debug_check_iterators)
2572 trans_for_each_path_inorder(trans, path, iter) {
2573 if (prev && btree_path_cmp(prev, path) > 0) {
2574 __bch2_dump_trans_paths_updates(trans, true);
2575 panic("trans paths out of order!\n");
2581 static inline void btree_trans_verify_sorted_refs(struct btree_trans *trans) {}
2582 static inline void btree_trans_verify_sorted(struct btree_trans *trans) {}
2585 void __bch2_btree_trans_sort_paths(struct btree_trans *trans)
2587 int i, l = 0, r = trans->nr_sorted, inc = 1;
2590 btree_trans_verify_sorted_refs(trans);
2592 if (trans->paths_sorted)
2596 * Cocktail shaker sort: this is efficient because iterators will be
2602 for (i = inc > 0 ? l : r - 2;
2603 i + 1 < r && i >= l;
2605 if (btree_path_cmp(trans->paths + trans->sorted[i],
2606 trans->paths + trans->sorted[i + 1]) > 0) {
2607 swap(trans->sorted[i], trans->sorted[i + 1]);
2608 trans->paths[trans->sorted[i]].sorted_idx = i;
2609 trans->paths[trans->sorted[i + 1]].sorted_idx = i + 1;
2621 trans->paths_sorted = true;
2623 btree_trans_verify_sorted(trans);
2626 static inline void btree_path_list_remove(struct btree_trans *trans,
2627 struct btree_path *path)
2631 EBUG_ON(path->sorted_idx >= trans->nr_sorted);
2632 #ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
2634 memmove_u64s_down_small(trans->sorted + path->sorted_idx,
2635 trans->sorted + path->sorted_idx + 1,
2636 DIV_ROUND_UP(trans->nr_sorted - path->sorted_idx, 8));
2638 array_remove_item(trans->sorted, trans->nr_sorted, path->sorted_idx);
2640 for (i = path->sorted_idx; i < trans->nr_sorted; i++)
2641 trans->paths[trans->sorted[i]].sorted_idx = i;
2643 path->sorted_idx = U8_MAX;
2646 static inline void btree_path_list_add(struct btree_trans *trans,
2647 btree_path_idx_t pos,
2648 btree_path_idx_t path_idx)
2650 struct btree_path *path = trans->paths + path_idx;
2653 path->sorted_idx = pos ? trans->paths[pos].sorted_idx + 1 : trans->nr_sorted;
2655 #ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
2656 memmove_u64s_up_small(trans->sorted + path->sorted_idx + 1,
2657 trans->sorted + path->sorted_idx,
2658 DIV_ROUND_UP(trans->nr_sorted - path->sorted_idx, 8));
2660 trans->sorted[path->sorted_idx] = path_idx;
2662 array_insert_item(trans->sorted, trans->nr_sorted, path->sorted_idx, path_idx);
2665 for (i = path->sorted_idx; i < trans->nr_sorted; i++)
2666 trans->paths[trans->sorted[i]].sorted_idx = i;
2668 btree_trans_verify_sorted_refs(trans);
2671 void bch2_trans_iter_exit(struct btree_trans *trans, struct btree_iter *iter)
2673 if (iter->update_path)
2674 bch2_path_put_nokeep(trans, iter->update_path,
2675 iter->flags & BTREE_ITER_INTENT);
2677 bch2_path_put(trans, iter->path,
2678 iter->flags & BTREE_ITER_INTENT);
2679 if (iter->key_cache_path)
2680 bch2_path_put(trans, iter->key_cache_path,
2681 iter->flags & BTREE_ITER_INTENT);
2683 iter->update_path = 0;
2684 iter->key_cache_path = 0;
2688 void bch2_trans_iter_init_outlined(struct btree_trans *trans,
2689 struct btree_iter *iter,
2690 enum btree_id btree_id, struct bpos pos,
2693 bch2_trans_iter_init_common(trans, iter, btree_id, pos, 0, 0,
2694 bch2_btree_iter_flags(trans, btree_id, flags),
2698 void bch2_trans_node_iter_init(struct btree_trans *trans,
2699 struct btree_iter *iter,
2700 enum btree_id btree_id,
2702 unsigned locks_want,
2706 flags |= BTREE_ITER_NOT_EXTENTS;
2707 flags |= __BTREE_ITER_ALL_SNAPSHOTS;
2708 flags |= BTREE_ITER_ALL_SNAPSHOTS;
2710 bch2_trans_iter_init_common(trans, iter, btree_id, pos, locks_want, depth,
2711 __bch2_btree_iter_flags(trans, btree_id, flags),
2714 iter->min_depth = depth;
2716 struct btree_path *path = btree_iter_path(trans, iter);
2717 BUG_ON(path->locks_want < min(locks_want, BTREE_MAX_DEPTH));
2718 BUG_ON(path->level != depth);
2719 BUG_ON(iter->min_depth != depth);
2722 void bch2_trans_copy_iter(struct btree_iter *dst, struct btree_iter *src)
2724 struct btree_trans *trans = src->trans;
2728 __btree_path_get(trans->paths + src->path, src->flags & BTREE_ITER_INTENT);
2729 if (src->update_path)
2730 __btree_path_get(trans->paths + src->update_path, src->flags & BTREE_ITER_INTENT);
2731 dst->key_cache_path = 0;
2734 void *__bch2_trans_kmalloc(struct btree_trans *trans, size_t size)
2736 struct bch_fs *c = trans->c;
2737 unsigned new_top = trans->mem_top + size;
2738 unsigned old_bytes = trans->mem_bytes;
2739 unsigned new_bytes = roundup_pow_of_two(new_top);
2744 WARN_ON_ONCE(new_bytes > BTREE_TRANS_MEM_MAX);
2746 struct btree_transaction_stats *s = btree_trans_stats(trans);
2748 s->max_mem = max(s->max_mem, new_bytes);
2750 new_mem = krealloc(trans->mem, new_bytes, GFP_NOWAIT|__GFP_NOWARN);
2751 if (unlikely(!new_mem)) {
2752 bch2_trans_unlock(trans);
2754 new_mem = krealloc(trans->mem, new_bytes, GFP_KERNEL);
2755 if (!new_mem && new_bytes <= BTREE_TRANS_MEM_MAX) {
2756 new_mem = mempool_alloc(&c->btree_trans_mem_pool, GFP_KERNEL);
2757 new_bytes = BTREE_TRANS_MEM_MAX;
2762 return ERR_PTR(-BCH_ERR_ENOMEM_trans_kmalloc);
2764 trans->mem = new_mem;
2765 trans->mem_bytes = new_bytes;
2767 ret = bch2_trans_relock(trans);
2769 return ERR_PTR(ret);
2772 trans->mem = new_mem;
2773 trans->mem_bytes = new_bytes;
2776 trace_and_count(c, trans_restart_mem_realloced, trans, _RET_IP_, new_bytes);
2777 return ERR_PTR(btree_trans_restart(trans, BCH_ERR_transaction_restart_mem_realloced));
2780 p = trans->mem + trans->mem_top;
2781 trans->mem_top += size;
2786 static inline void check_srcu_held_too_long(struct btree_trans *trans)
2788 WARN(trans->srcu_held && time_after(jiffies, trans->srcu_lock_time + HZ * 10),
2789 "btree trans held srcu lock (delaying memory reclaim) for %lu seconds",
2790 (jiffies - trans->srcu_lock_time) / HZ);
2793 void bch2_trans_srcu_unlock(struct btree_trans *trans)
2795 if (trans->srcu_held) {
2796 struct bch_fs *c = trans->c;
2797 struct btree_path *path;
2800 trans_for_each_path(trans, path, i)
2801 if (path->cached && !btree_node_locked(path, 0))
2802 path->l[0].b = ERR_PTR(-BCH_ERR_no_btree_node_srcu_reset);
2804 check_srcu_held_too_long(trans);
2805 srcu_read_unlock(&c->btree_trans_barrier, trans->srcu_idx);
2806 trans->srcu_held = false;
2810 static void bch2_trans_srcu_lock(struct btree_trans *trans)
2812 if (!trans->srcu_held) {
2813 trans->srcu_idx = srcu_read_lock(&trans->c->btree_trans_barrier);
2814 trans->srcu_lock_time = jiffies;
2815 trans->srcu_held = true;
2820 * bch2_trans_begin() - reset a transaction after a interrupted attempt
2821 * @trans: transaction to reset
2823 * Returns: current restart counter, to be used with trans_was_restarted()
2825 * While iterating over nodes or updating nodes a attempt to lock a btree node
2826 * may return BCH_ERR_transaction_restart when the trylock fails. When this
2827 * occurs bch2_trans_begin() should be called and the transaction retried.
2829 u32 bch2_trans_begin(struct btree_trans *trans)
2831 struct btree_path *path;
2835 bch2_trans_reset_updates(trans);
2837 trans->restart_count++;
2839 trans->journal_entries = NULL;
2841 trans_for_each_path(trans, path, i) {
2842 path->should_be_locked = false;
2845 * If the transaction wasn't restarted, we're presuming to be
2846 * doing something new: dont keep iterators excpt the ones that
2847 * are in use - except for the subvolumes btree:
2849 if (!trans->restarted && path->btree_id != BTREE_ID_subvolumes)
2850 path->preserve = false;
2853 * XXX: we probably shouldn't be doing this if the transaction
2854 * was restarted, but currently we still overflow transaction
2855 * iterators if we do that
2857 if (!path->ref && !path->preserve)
2858 __bch2_path_free(trans, i);
2860 path->preserve = false;
2863 now = local_clock();
2864 if (!trans->restarted &&
2866 now - trans->last_begin_time > BTREE_TRANS_MAX_LOCK_HOLD_TIME_NS)) {
2867 drop_locks_do(trans, (cond_resched(), 0));
2868 now = local_clock();
2870 trans->last_begin_time = now;
2872 if (unlikely(trans->srcu_held &&
2873 time_after(jiffies, trans->srcu_lock_time + msecs_to_jiffies(10))))
2874 bch2_trans_srcu_unlock(trans);
2876 trans->last_begin_ip = _RET_IP_;
2877 if (trans->restarted) {
2878 bch2_btree_path_traverse_all(trans);
2879 trans->notrace_relock_fail = false;
2882 return trans->restart_count;
2885 const char *bch2_btree_transaction_fns[BCH_TRANSACTIONS_NR];
2887 unsigned bch2_trans_get_fn_idx(const char *fn)
2891 for (i = 0; i < ARRAY_SIZE(bch2_btree_transaction_fns); i++)
2892 if (!bch2_btree_transaction_fns[i] ||
2893 bch2_btree_transaction_fns[i] == fn) {
2894 bch2_btree_transaction_fns[i] = fn;
2898 pr_warn_once("BCH_TRANSACTIONS_NR not big enough!");
2902 struct btree_trans *__bch2_trans_get(struct bch_fs *c, unsigned fn_idx)
2903 __acquires(&c->btree_trans_barrier)
2905 struct btree_trans *trans;
2907 if (IS_ENABLED(__KERNEL__)) {
2908 trans = this_cpu_xchg(c->btree_trans_bufs->trans, NULL);
2910 memset(trans, 0, offsetof(struct btree_trans, list));
2915 trans = mempool_alloc(&c->btree_trans_pool, GFP_NOFS);
2916 memset(trans, 0, sizeof(*trans));
2917 closure_init_stack(&trans->ref);
2919 seqmutex_lock(&c->btree_trans_lock);
2920 if (IS_ENABLED(CONFIG_BCACHEFS_DEBUG)) {
2921 struct btree_trans *pos;
2922 pid_t pid = current->pid;
2924 trans->locking_wait.task = current;
2926 list_for_each_entry(pos, &c->btree_trans_list, list) {
2927 struct task_struct *pos_task = READ_ONCE(pos->locking_wait.task);
2929 * We'd much prefer to be stricter here and completely
2930 * disallow multiple btree_trans in the same thread -
2931 * but the data move path calls bch2_write when we
2932 * already have a btree_trans initialized.
2935 pid == pos_task->pid &&
2936 bch2_trans_locked(pos));
2938 if (pos_task && pid < pos_task->pid) {
2939 list_add_tail(&trans->list, &pos->list);
2944 list_add_tail(&trans->list, &c->btree_trans_list);
2946 seqmutex_unlock(&c->btree_trans_lock);
2949 trans->last_begin_time = local_clock();
2950 trans->fn_idx = fn_idx;
2951 trans->locking_wait.task = current;
2952 trans->journal_replay_not_finished =
2953 unlikely(!test_bit(JOURNAL_REPLAY_DONE, &c->journal.flags)) &&
2954 atomic_inc_not_zero(&c->journal_keys.ref);
2955 trans->nr_paths = ARRAY_SIZE(trans->_paths);
2956 trans->paths_allocated = trans->_paths_allocated;
2957 trans->sorted = trans->_sorted;
2958 trans->paths = trans->_paths;
2959 trans->updates = trans->_updates;
2961 *trans_paths_nr(trans->paths) = BTREE_ITER_MAX;
2963 trans->paths_allocated[0] = 1;
2965 if (fn_idx < BCH_TRANSACTIONS_NR) {
2966 trans->fn = bch2_btree_transaction_fns[fn_idx];
2968 struct btree_transaction_stats *s = &c->btree_transaction_stats[fn_idx];
2971 unsigned expected_mem_bytes = roundup_pow_of_two(s->max_mem);
2973 trans->mem = kmalloc(expected_mem_bytes, GFP_KERNEL);
2974 if (likely(trans->mem))
2975 trans->mem_bytes = expected_mem_bytes;
2978 trans->nr_paths_max = s->nr_max_paths;
2979 trans->journal_entries_size = s->journal_entries_size;
2982 trans->srcu_idx = srcu_read_lock(&c->btree_trans_barrier);
2983 trans->srcu_lock_time = jiffies;
2984 trans->srcu_held = true;
2988 static void check_btree_paths_leaked(struct btree_trans *trans)
2990 #ifdef CONFIG_BCACHEFS_DEBUG
2991 struct bch_fs *c = trans->c;
2992 struct btree_path *path;
2995 trans_for_each_path(trans, path, i)
3000 bch_err(c, "btree paths leaked from %s!", trans->fn);
3001 trans_for_each_path(trans, path, i)
3003 printk(KERN_ERR " btree %s %pS\n",
3004 bch2_btree_id_str(path->btree_id),
3005 (void *) path->ip_allocated);
3006 /* Be noisy about this: */
3007 bch2_fatal_error(c);
3011 void bch2_trans_put(struct btree_trans *trans)
3012 __releases(&c->btree_trans_barrier)
3014 struct bch_fs *c = trans->c;
3016 bch2_trans_unlock(trans);
3018 trans_for_each_update(trans, i)
3019 __btree_path_put(trans->paths + i->path, true);
3020 trans->nr_updates = 0;
3021 trans->locking_wait.task = NULL;
3023 check_btree_paths_leaked(trans);
3025 if (trans->srcu_held) {
3026 check_srcu_held_too_long(trans);
3027 srcu_read_unlock(&c->btree_trans_barrier, trans->srcu_idx);
3030 if (trans->fs_usage_deltas) {
3031 if (trans->fs_usage_deltas->size + sizeof(trans->fs_usage_deltas) ==
3032 REPLICAS_DELTA_LIST_MAX)
3033 mempool_free(trans->fs_usage_deltas,
3034 &c->replicas_delta_pool);
3036 kfree(trans->fs_usage_deltas);
3039 if (unlikely(trans->journal_replay_not_finished))
3040 bch2_journal_keys_put(c);
3042 unsigned long *paths_allocated = trans->paths_allocated;
3043 trans->paths_allocated = NULL;
3044 trans->paths = NULL;
3046 if (paths_allocated != trans->_paths_allocated)
3047 kfree_rcu_mightsleep(paths_allocated);
3049 if (trans->mem_bytes == BTREE_TRANS_MEM_MAX)
3050 mempool_free(trans->mem, &c->btree_trans_mem_pool);
3054 /* Userspace doesn't have a real percpu implementation: */
3055 if (IS_ENABLED(__KERNEL__))
3056 trans = this_cpu_xchg(c->btree_trans_bufs->trans, trans);
3059 closure_sync(&trans->ref);
3061 seqmutex_lock(&c->btree_trans_lock);
3062 list_del(&trans->list);
3063 seqmutex_unlock(&c->btree_trans_lock);
3065 mempool_free(trans, &c->btree_trans_pool);
3069 static void __maybe_unused
3070 bch2_btree_bkey_cached_common_to_text(struct printbuf *out,
3071 struct btree_bkey_cached_common *b)
3073 struct six_lock_count c = six_lock_counts(&b->lock);
3074 struct task_struct *owner;
3078 owner = READ_ONCE(b->lock.owner);
3079 pid = owner ? owner->pid : 0;
3083 prt_printf(out, "%px %c l=%u %s:", b, b->cached ? 'c' : 'b',
3084 b->level, bch2_btree_id_str(b->btree_id));
3085 bch2_bpos_to_text(out, btree_node_pos(b));
3088 prt_printf(out, " locks %u:%u:%u held by pid %u",
3089 c.n[0], c.n[1], c.n[2], pid);
3092 void bch2_btree_trans_to_text(struct printbuf *out, struct btree_trans *trans)
3094 struct btree_bkey_cached_common *b;
3095 static char lock_types[] = { 'r', 'i', 'w' };
3096 struct task_struct *task = READ_ONCE(trans->locking_wait.task);
3099 /* before rcu_read_lock(): */
3100 bch2_printbuf_make_room(out, 4096);
3102 if (!out->nr_tabstops) {
3103 printbuf_tabstop_push(out, 16);
3104 printbuf_tabstop_push(out, 32);
3107 prt_printf(out, "%i %s\n", task ? task->pid : 0, trans->fn);
3109 /* trans->paths is rcu protected vs. freeing */
3113 struct btree_path *paths = rcu_dereference(trans->paths);
3117 unsigned long *paths_allocated = trans_paths_allocated(paths);
3119 trans_for_each_path_idx_from(paths_allocated, *trans_paths_nr(paths), idx, 1) {
3120 struct btree_path *path = paths + idx;
3121 if (!path->nodes_locked)
3124 prt_printf(out, " path %u %c l=%u %s:",
3126 path->cached ? 'c' : 'b',
3128 bch2_btree_id_str(path->btree_id));
3129 bch2_bpos_to_text(out, path->pos);
3132 for (l = 0; l < BTREE_MAX_DEPTH; l++) {
3133 if (btree_node_locked(path, l) &&
3134 !IS_ERR_OR_NULL(b = (void *) READ_ONCE(path->l[l].b))) {
3135 prt_printf(out, " %c l=%u ",
3136 lock_types[btree_node_locked_type(path, l)], l);
3137 bch2_btree_bkey_cached_common_to_text(out, b);
3143 b = READ_ONCE(trans->locking);
3145 prt_printf(out, " blocked for %lluus on",
3146 div_u64(local_clock() - trans->locking_wait.start_time,
3149 prt_printf(out, " %c", lock_types[trans->locking_wait.lock_want]);
3150 bch2_btree_bkey_cached_common_to_text(out, b);
3158 void bch2_fs_btree_iter_exit(struct bch_fs *c)
3160 struct btree_transaction_stats *s;
3161 struct btree_trans *trans;
3164 if (c->btree_trans_bufs)
3165 for_each_possible_cpu(cpu) {
3166 struct btree_trans *trans =
3167 per_cpu_ptr(c->btree_trans_bufs, cpu)->trans;
3170 closure_sync(&trans->ref);
3172 seqmutex_lock(&c->btree_trans_lock);
3173 list_del(&trans->list);
3174 seqmutex_unlock(&c->btree_trans_lock);
3178 free_percpu(c->btree_trans_bufs);
3180 trans = list_first_entry_or_null(&c->btree_trans_list, struct btree_trans, list);
3182 panic("%s leaked btree_trans\n", trans->fn);
3184 for (s = c->btree_transaction_stats;
3185 s < c->btree_transaction_stats + ARRAY_SIZE(c->btree_transaction_stats);
3187 kfree(s->max_paths_text);
3188 bch2_time_stats_exit(&s->lock_hold_times);
3191 if (c->btree_trans_barrier_initialized)
3192 cleanup_srcu_struct(&c->btree_trans_barrier);
3193 mempool_exit(&c->btree_trans_mem_pool);
3194 mempool_exit(&c->btree_trans_pool);
3197 void bch2_fs_btree_iter_init_early(struct bch_fs *c)
3199 struct btree_transaction_stats *s;
3201 for (s = c->btree_transaction_stats;
3202 s < c->btree_transaction_stats + ARRAY_SIZE(c->btree_transaction_stats);
3204 bch2_time_stats_init(&s->lock_hold_times);
3205 mutex_init(&s->lock);
3208 INIT_LIST_HEAD(&c->btree_trans_list);
3209 seqmutex_init(&c->btree_trans_lock);
3212 int bch2_fs_btree_iter_init(struct bch_fs *c)
3216 c->btree_trans_bufs = alloc_percpu(struct btree_trans_buf);
3217 if (!c->btree_trans_bufs)
3220 ret = mempool_init_kmalloc_pool(&c->btree_trans_pool, 1,
3221 sizeof(struct btree_trans)) ?:
3222 mempool_init_kmalloc_pool(&c->btree_trans_mem_pool, 1,
3223 BTREE_TRANS_MEM_MAX) ?:
3224 init_srcu_struct(&c->btree_trans_barrier);
3226 c->btree_trans_barrier_initialized = true;