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_key_cache.h"
9 #include "btree_locking.h"
10 #include "btree_update.h"
17 #include "subvolume.h"
20 #include <linux/random.h>
21 #include <linux/prefetch.h>
23 static inline void btree_path_list_remove(struct btree_trans *, struct btree_path *);
24 static inline void btree_path_list_add(struct btree_trans *, struct btree_path *,
27 static inline unsigned long btree_iter_ip_allocated(struct btree_iter *iter)
29 #ifdef TRACK_PATH_ALLOCATED
30 return iter->ip_allocated;
36 static struct btree_path *btree_path_alloc(struct btree_trans *, struct btree_path *);
39 * Unlocks before scheduling
40 * Note: does not revalidate iterator
42 static inline int bch2_trans_cond_resched(struct btree_trans *trans)
44 if (need_resched() || race_fault()) {
45 bch2_trans_unlock(trans);
47 return bch2_trans_relock(trans);
53 static inline int __btree_path_cmp(const struct btree_path *l,
54 enum btree_id r_btree_id,
60 * Must match lock ordering as defined by __bch2_btree_node_lock:
62 return cmp_int(l->btree_id, r_btree_id) ?:
63 cmp_int((int) l->cached, (int) r_cached) ?:
64 bpos_cmp(l->pos, r_pos) ?:
65 -cmp_int(l->level, r_level);
68 static inline int btree_path_cmp(const struct btree_path *l,
69 const struct btree_path *r)
71 return __btree_path_cmp(l, r->btree_id, r->cached, r->pos, r->level);
74 static inline struct bpos bkey_successor(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_successor(p);
80 p = bpos_nosnap_successor(p);
81 p.snapshot = iter->snapshot;
87 static inline struct bpos bkey_predecessor(struct btree_iter *iter, struct bpos p)
89 /* Are we iterating over keys in all snapshots? */
90 if (iter->flags & BTREE_ITER_ALL_SNAPSHOTS) {
91 p = bpos_predecessor(p);
93 p = bpos_nosnap_predecessor(p);
94 p.snapshot = iter->snapshot;
100 static inline struct bpos btree_iter_search_key(struct btree_iter *iter)
102 struct bpos pos = iter->pos;
104 if ((iter->flags & BTREE_ITER_IS_EXTENTS) &&
105 !bkey_eq(pos, POS_MAX))
106 pos = bkey_successor(iter, pos);
110 static inline bool btree_path_pos_before_node(struct btree_path *path,
113 return bpos_lt(path->pos, b->data->min_key);
116 static inline bool btree_path_pos_after_node(struct btree_path *path,
119 return bpos_gt(path->pos, b->key.k.p);
122 static inline bool btree_path_pos_in_node(struct btree_path *path,
125 return path->btree_id == b->c.btree_id &&
126 !btree_path_pos_before_node(path, b) &&
127 !btree_path_pos_after_node(path, b);
130 /* Btree iterator: */
132 #ifdef CONFIG_BCACHEFS_DEBUG
134 static void bch2_btree_path_verify_cached(struct btree_trans *trans,
135 struct btree_path *path)
137 struct bkey_cached *ck;
138 bool locked = btree_node_locked(path, 0);
140 if (!bch2_btree_node_relock(trans, path, 0))
143 ck = (void *) path->l[0].b;
144 BUG_ON(ck->key.btree_id != path->btree_id ||
145 !bkey_eq(ck->key.pos, path->pos));
148 btree_node_unlock(trans, path, 0);
151 static void bch2_btree_path_verify_level(struct btree_trans *trans,
152 struct btree_path *path, unsigned level)
154 struct btree_path_level *l;
155 struct btree_node_iter tmp;
157 struct bkey_packed *p, *k;
158 struct printbuf buf1 = PRINTBUF;
159 struct printbuf buf2 = PRINTBUF;
160 struct printbuf buf3 = PRINTBUF;
163 if (!bch2_debug_check_iterators)
168 locked = btree_node_locked(path, level);
172 bch2_btree_path_verify_cached(trans, path);
176 if (!btree_path_node(path, level))
179 if (!bch2_btree_node_relock_notrace(trans, path, level))
182 BUG_ON(!btree_path_pos_in_node(path, l->b));
184 bch2_btree_node_iter_verify(&l->iter, l->b);
187 * For interior nodes, the iterator will have skipped past deleted keys:
190 ? bch2_btree_node_iter_prev(&tmp, l->b)
191 : bch2_btree_node_iter_prev_all(&tmp, l->b);
192 k = bch2_btree_node_iter_peek_all(&l->iter, l->b);
194 if (p && bkey_iter_pos_cmp(l->b, p, &path->pos) >= 0) {
199 if (k && bkey_iter_pos_cmp(l->b, k, &path->pos) < 0) {
205 btree_node_unlock(trans, path, level);
208 bch2_bpos_to_text(&buf1, path->pos);
211 struct bkey uk = bkey_unpack_key(l->b, p);
213 bch2_bkey_to_text(&buf2, &uk);
215 prt_printf(&buf2, "(none)");
219 struct bkey uk = bkey_unpack_key(l->b, k);
221 bch2_bkey_to_text(&buf3, &uk);
223 prt_printf(&buf3, "(none)");
226 panic("path should be %s key at level %u:\n"
230 msg, level, buf1.buf, buf2.buf, buf3.buf);
233 static void bch2_btree_path_verify(struct btree_trans *trans,
234 struct btree_path *path)
236 struct bch_fs *c = trans->c;
239 EBUG_ON(path->btree_id >= BTREE_ID_NR);
241 for (i = 0; i < (!path->cached ? BTREE_MAX_DEPTH : 1); i++) {
243 BUG_ON(!path->cached &&
244 c->btree_roots[path->btree_id].b->c.level > i);
248 bch2_btree_path_verify_level(trans, path, i);
251 bch2_btree_path_verify_locks(path);
254 void bch2_trans_verify_paths(struct btree_trans *trans)
256 struct btree_path *path;
258 trans_for_each_path(trans, path)
259 bch2_btree_path_verify(trans, path);
262 static void bch2_btree_iter_verify(struct btree_iter *iter)
264 struct btree_trans *trans = iter->trans;
266 BUG_ON(iter->btree_id >= BTREE_ID_NR);
268 BUG_ON(!!(iter->flags & BTREE_ITER_CACHED) != iter->path->cached);
270 BUG_ON((iter->flags & BTREE_ITER_IS_EXTENTS) &&
271 (iter->flags & BTREE_ITER_ALL_SNAPSHOTS));
273 BUG_ON(!(iter->flags & __BTREE_ITER_ALL_SNAPSHOTS) &&
274 (iter->flags & BTREE_ITER_ALL_SNAPSHOTS) &&
275 !btree_type_has_snapshots(iter->btree_id));
277 if (iter->update_path)
278 bch2_btree_path_verify(trans, iter->update_path);
279 bch2_btree_path_verify(trans, iter->path);
282 static void bch2_btree_iter_verify_entry_exit(struct btree_iter *iter)
284 BUG_ON((iter->flags & BTREE_ITER_FILTER_SNAPSHOTS) &&
285 !iter->pos.snapshot);
287 BUG_ON(!(iter->flags & BTREE_ITER_ALL_SNAPSHOTS) &&
288 iter->pos.snapshot != iter->snapshot);
290 BUG_ON(bkey_lt(iter->pos, bkey_start_pos(&iter->k)) ||
291 bkey_gt(iter->pos, iter->k.p));
294 static int bch2_btree_iter_verify_ret(struct btree_iter *iter, struct bkey_s_c k)
296 struct btree_trans *trans = iter->trans;
297 struct btree_iter copy;
298 struct bkey_s_c prev;
301 if (!bch2_debug_check_iterators)
304 if (!(iter->flags & BTREE_ITER_FILTER_SNAPSHOTS))
307 if (bkey_err(k) || !k.k)
310 BUG_ON(!bch2_snapshot_is_ancestor(trans->c,
314 bch2_trans_iter_init(trans, ©, iter->btree_id, iter->pos,
315 BTREE_ITER_NOPRESERVE|
316 BTREE_ITER_ALL_SNAPSHOTS);
317 prev = bch2_btree_iter_prev(©);
321 ret = bkey_err(prev);
325 if (bkey_eq(prev.k->p, k.k->p) &&
326 bch2_snapshot_is_ancestor(trans->c, iter->snapshot,
327 prev.k->p.snapshot) > 0) {
328 struct printbuf buf1 = PRINTBUF, buf2 = PRINTBUF;
330 bch2_bkey_to_text(&buf1, k.k);
331 bch2_bkey_to_text(&buf2, prev.k);
333 panic("iter snap %u\n"
340 bch2_trans_iter_exit(trans, ©);
344 void bch2_assert_pos_locked(struct btree_trans *trans, enum btree_id id,
345 struct bpos pos, bool key_cache)
347 struct btree_path *path;
349 struct printbuf buf = PRINTBUF;
351 btree_trans_sort_paths(trans);
353 trans_for_each_path_inorder(trans, path, idx) {
354 int cmp = cmp_int(path->btree_id, id) ?:
355 cmp_int(path->cached, key_cache);
362 if (!btree_node_locked(path, 0) ||
363 !path->should_be_locked)
367 if (bkey_ge(pos, path->l[0].b->data->min_key) &&
368 bkey_le(pos, path->l[0].b->key.k.p))
371 if (bkey_eq(pos, path->pos))
376 bch2_dump_trans_paths_updates(trans);
377 bch2_bpos_to_text(&buf, pos);
379 panic("not locked: %s %s%s\n",
380 bch2_btree_ids[id], buf.buf,
381 key_cache ? " cached" : "");
386 static inline void bch2_btree_path_verify_level(struct btree_trans *trans,
387 struct btree_path *path, unsigned l) {}
388 static inline void bch2_btree_path_verify(struct btree_trans *trans,
389 struct btree_path *path) {}
390 static inline void bch2_btree_iter_verify(struct btree_iter *iter) {}
391 static inline void bch2_btree_iter_verify_entry_exit(struct btree_iter *iter) {}
392 static inline int bch2_btree_iter_verify_ret(struct btree_iter *iter, struct bkey_s_c k) { return 0; }
396 /* Btree path: fixups after btree updates */
398 static void btree_node_iter_set_set_pos(struct btree_node_iter *iter,
401 struct bkey_packed *k)
403 struct btree_node_iter_set *set;
405 btree_node_iter_for_each(iter, set)
406 if (set->end == t->end_offset) {
407 set->k = __btree_node_key_to_offset(b, k);
408 bch2_btree_node_iter_sort(iter, b);
412 bch2_btree_node_iter_push(iter, b, k, btree_bkey_last(b, t));
415 static void __bch2_btree_path_fix_key_modified(struct btree_path *path,
417 struct bkey_packed *where)
419 struct btree_path_level *l = &path->l[b->c.level];
421 if (where != bch2_btree_node_iter_peek_all(&l->iter, l->b))
424 if (bkey_iter_pos_cmp(l->b, where, &path->pos) < 0)
425 bch2_btree_node_iter_advance(&l->iter, l->b);
428 void bch2_btree_path_fix_key_modified(struct btree_trans *trans,
430 struct bkey_packed *where)
432 struct btree_path *path;
434 trans_for_each_path_with_node(trans, b, path) {
435 __bch2_btree_path_fix_key_modified(path, b, where);
436 bch2_btree_path_verify_level(trans, path, b->c.level);
440 static void __bch2_btree_node_iter_fix(struct btree_path *path,
442 struct btree_node_iter *node_iter,
444 struct bkey_packed *where,
445 unsigned clobber_u64s,
448 const struct bkey_packed *end = btree_bkey_last(b, t);
449 struct btree_node_iter_set *set;
450 unsigned offset = __btree_node_key_to_offset(b, where);
451 int shift = new_u64s - clobber_u64s;
452 unsigned old_end = t->end_offset - shift;
453 unsigned orig_iter_pos = node_iter->data[0].k;
454 bool iter_current_key_modified =
455 orig_iter_pos >= offset &&
456 orig_iter_pos <= offset + clobber_u64s;
458 btree_node_iter_for_each(node_iter, set)
459 if (set->end == old_end)
462 /* didn't find the bset in the iterator - might have to readd it: */
464 bkey_iter_pos_cmp(b, where, &path->pos) >= 0) {
465 bch2_btree_node_iter_push(node_iter, b, where, end);
468 /* Iterator is after key that changed */
472 set->end = t->end_offset;
474 /* Iterator hasn't gotten to the key that changed yet: */
479 bkey_iter_pos_cmp(b, where, &path->pos) >= 0) {
481 } else if (set->k < offset + clobber_u64s) {
482 set->k = offset + new_u64s;
483 if (set->k == set->end)
484 bch2_btree_node_iter_set_drop(node_iter, set);
486 /* Iterator is after key that changed */
487 set->k = (int) set->k + shift;
491 bch2_btree_node_iter_sort(node_iter, b);
493 if (node_iter->data[0].k != orig_iter_pos)
494 iter_current_key_modified = true;
497 * When a new key is added, and the node iterator now points to that
498 * key, the iterator might have skipped past deleted keys that should
499 * come after the key the iterator now points to. We have to rewind to
500 * before those deleted keys - otherwise
501 * bch2_btree_node_iter_prev_all() breaks:
503 if (!bch2_btree_node_iter_end(node_iter) &&
504 iter_current_key_modified &&
507 struct bkey_packed *k, *k2, *p;
509 k = bch2_btree_node_iter_peek_all(node_iter, b);
511 for_each_bset(b, t) {
512 bool set_pos = false;
514 if (node_iter->data[0].end == t->end_offset)
517 k2 = bch2_btree_node_iter_bset_pos(node_iter, b, t);
519 while ((p = bch2_bkey_prev_all(b, t, k2)) &&
520 bkey_iter_cmp(b, k, p) < 0) {
526 btree_node_iter_set_set_pos(node_iter,
532 void bch2_btree_node_iter_fix(struct btree_trans *trans,
533 struct btree_path *path,
535 struct btree_node_iter *node_iter,
536 struct bkey_packed *where,
537 unsigned clobber_u64s,
540 struct bset_tree *t = bch2_bkey_to_bset_inlined(b, where);
541 struct btree_path *linked;
543 if (node_iter != &path->l[b->c.level].iter) {
544 __bch2_btree_node_iter_fix(path, b, node_iter, t,
545 where, clobber_u64s, new_u64s);
547 if (bch2_debug_check_iterators)
548 bch2_btree_node_iter_verify(node_iter, b);
551 trans_for_each_path_with_node(trans, b, linked) {
552 __bch2_btree_node_iter_fix(linked, b,
553 &linked->l[b->c.level].iter, t,
554 where, clobber_u64s, new_u64s);
555 bch2_btree_path_verify_level(trans, linked, b->c.level);
559 /* Btree path level: pointer to a particular btree node and node iter */
561 static inline struct bkey_s_c __btree_iter_unpack(struct bch_fs *c,
562 struct btree_path_level *l,
564 struct bkey_packed *k)
568 * signal to bch2_btree_iter_peek_slot() that we're currently at
571 u->type = KEY_TYPE_deleted;
572 return bkey_s_c_null;
575 return bkey_disassemble(l->b, k, u);
578 static inline struct bkey_s_c btree_path_level_peek_all(struct bch_fs *c,
579 struct btree_path_level *l,
582 return __btree_iter_unpack(c, l, u,
583 bch2_btree_node_iter_peek_all(&l->iter, l->b));
586 static inline struct bkey_s_c btree_path_level_peek(struct btree_trans *trans,
587 struct btree_path *path,
588 struct btree_path_level *l,
591 struct bkey_s_c k = __btree_iter_unpack(trans->c, l, u,
592 bch2_btree_node_iter_peek(&l->iter, l->b));
594 path->pos = k.k ? k.k->p : l->b->key.k.p;
595 trans->paths_sorted = false;
596 bch2_btree_path_verify_level(trans, path, l - path->l);
600 static inline struct bkey_s_c btree_path_level_prev(struct btree_trans *trans,
601 struct btree_path *path,
602 struct btree_path_level *l,
605 struct bkey_s_c k = __btree_iter_unpack(trans->c, l, u,
606 bch2_btree_node_iter_prev(&l->iter, l->b));
608 path->pos = k.k ? k.k->p : l->b->data->min_key;
609 trans->paths_sorted = false;
610 bch2_btree_path_verify_level(trans, path, l - path->l);
614 static inline bool btree_path_advance_to_pos(struct btree_path *path,
615 struct btree_path_level *l,
618 struct bkey_packed *k;
621 while ((k = bch2_btree_node_iter_peek_all(&l->iter, l->b)) &&
622 bkey_iter_pos_cmp(l->b, k, &path->pos) < 0) {
623 if (max_advance > 0 && nr_advanced >= max_advance)
626 bch2_btree_node_iter_advance(&l->iter, l->b);
633 static inline void __btree_path_level_init(struct btree_path *path,
636 struct btree_path_level *l = &path->l[level];
638 bch2_btree_node_iter_init(&l->iter, l->b, &path->pos);
641 * Iterators to interior nodes should always be pointed at the first non
645 bch2_btree_node_iter_peek(&l->iter, l->b);
648 void bch2_btree_path_level_init(struct btree_trans *trans,
649 struct btree_path *path,
652 BUG_ON(path->cached);
654 EBUG_ON(!btree_path_pos_in_node(path, b));
656 path->l[b->c.level].lock_seq = six_lock_seq(&b->c.lock);
657 path->l[b->c.level].b = b;
658 __btree_path_level_init(path, b->c.level);
661 /* Btree path: fixups after btree node updates: */
663 static void bch2_trans_revalidate_updates_in_node(struct btree_trans *trans, struct btree *b)
665 struct bch_fs *c = trans->c;
666 struct btree_insert_entry *i;
668 trans_for_each_update(trans, i)
670 i->level == b->c.level &&
671 i->btree_id == b->c.btree_id &&
672 bpos_cmp(i->k->k.p, b->data->min_key) >= 0 &&
673 bpos_cmp(i->k->k.p, b->data->max_key) <= 0) {
674 i->old_v = bch2_btree_path_peek_slot(i->path, &i->old_k).v;
676 if (unlikely(trans->journal_replay_not_finished)) {
678 bch2_journal_keys_peek_slot(c, i->btree_id, i->level,
690 * A btree node is being replaced - update the iterator to point to the new
693 void bch2_trans_node_add(struct btree_trans *trans, struct btree *b)
695 struct btree_path *path;
697 trans_for_each_path(trans, path)
698 if (path->uptodate == BTREE_ITER_UPTODATE &&
700 btree_path_pos_in_node(path, b)) {
701 enum btree_node_locked_type t =
702 btree_lock_want(path, b->c.level);
704 if (t != BTREE_NODE_UNLOCKED) {
705 btree_node_unlock(trans, path, b->c.level);
706 six_lock_increment(&b->c.lock, t);
707 mark_btree_node_locked(trans, path, b->c.level, t);
710 bch2_btree_path_level_init(trans, path, b);
713 bch2_trans_revalidate_updates_in_node(trans, b);
717 * A btree node has been modified in such a way as to invalidate iterators - fix
720 void bch2_trans_node_reinit_iter(struct btree_trans *trans, struct btree *b)
722 struct btree_path *path;
724 trans_for_each_path_with_node(trans, b, path)
725 __btree_path_level_init(path, b->c.level);
727 bch2_trans_revalidate_updates_in_node(trans, b);
730 /* Btree path: traverse, set_pos: */
732 static inline int btree_path_lock_root(struct btree_trans *trans,
733 struct btree_path *path,
735 unsigned long trace_ip)
737 struct bch_fs *c = trans->c;
738 struct btree *b, **rootp = &c->btree_roots[path->btree_id].b;
739 enum six_lock_type lock_type;
743 EBUG_ON(path->nodes_locked);
746 b = READ_ONCE(*rootp);
747 path->level = READ_ONCE(b->c.level);
749 if (unlikely(path->level < depth_want)) {
751 * the root is at a lower depth than the depth we want:
752 * got to the end of the btree, or we're walking nodes
753 * greater than some depth and there are no nodes >=
756 path->level = depth_want;
757 for (i = path->level; i < BTREE_MAX_DEPTH; i++)
762 lock_type = __btree_lock_want(path, path->level);
763 ret = btree_node_lock(trans, path, &b->c,
764 path->level, lock_type, trace_ip);
766 if (bch2_err_matches(ret, BCH_ERR_lock_fail_root_changed))
768 if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
773 if (likely(b == READ_ONCE(*rootp) &&
774 b->c.level == path->level &&
776 for (i = 0; i < path->level; i++)
777 path->l[i].b = ERR_PTR(-BCH_ERR_no_btree_node_lock_root);
778 path->l[path->level].b = b;
779 for (i = path->level + 1; i < BTREE_MAX_DEPTH; i++)
782 mark_btree_node_locked(trans, path, path->level, lock_type);
783 bch2_btree_path_level_init(trans, path, b);
787 six_unlock_type(&b->c.lock, lock_type);
792 static int btree_path_prefetch(struct btree_trans *trans, struct btree_path *path)
794 struct bch_fs *c = trans->c;
795 struct btree_path_level *l = path_l(path);
796 struct btree_node_iter node_iter = l->iter;
797 struct bkey_packed *k;
799 unsigned nr = test_bit(BCH_FS_STARTED, &c->flags)
800 ? (path->level > 1 ? 0 : 2)
801 : (path->level > 1 ? 1 : 16);
802 bool was_locked = btree_node_locked(path, path->level);
805 bch2_bkey_buf_init(&tmp);
807 while (nr-- && !ret) {
808 if (!bch2_btree_node_relock(trans, path, path->level))
811 bch2_btree_node_iter_advance(&node_iter, l->b);
812 k = bch2_btree_node_iter_peek(&node_iter, l->b);
816 bch2_bkey_buf_unpack(&tmp, c, l->b, k);
817 ret = bch2_btree_node_prefetch(trans, path, tmp.k, path->btree_id,
822 btree_node_unlock(trans, path, path->level);
824 bch2_bkey_buf_exit(&tmp, c);
828 static int btree_path_prefetch_j(struct btree_trans *trans, struct btree_path *path,
829 struct btree_and_journal_iter *jiter)
831 struct bch_fs *c = trans->c;
834 unsigned nr = test_bit(BCH_FS_STARTED, &c->flags)
835 ? (path->level > 1 ? 0 : 2)
836 : (path->level > 1 ? 1 : 16);
837 bool was_locked = btree_node_locked(path, path->level);
840 bch2_bkey_buf_init(&tmp);
842 while (nr-- && !ret) {
843 if (!bch2_btree_node_relock(trans, path, path->level))
846 bch2_btree_and_journal_iter_advance(jiter);
847 k = bch2_btree_and_journal_iter_peek(jiter);
851 bch2_bkey_buf_reassemble(&tmp, c, k);
852 ret = bch2_btree_node_prefetch(trans, path, tmp.k, path->btree_id,
857 btree_node_unlock(trans, path, path->level);
859 bch2_bkey_buf_exit(&tmp, c);
863 static noinline void btree_node_mem_ptr_set(struct btree_trans *trans,
864 struct btree_path *path,
865 unsigned plevel, struct btree *b)
867 struct btree_path_level *l = &path->l[plevel];
868 bool locked = btree_node_locked(path, plevel);
869 struct bkey_packed *k;
870 struct bch_btree_ptr_v2 *bp;
872 if (!bch2_btree_node_relock(trans, path, plevel))
875 k = bch2_btree_node_iter_peek_all(&l->iter, l->b);
876 BUG_ON(k->type != KEY_TYPE_btree_ptr_v2);
878 bp = (void *) bkeyp_val(&l->b->format, k);
879 bp->mem_ptr = (unsigned long)b;
882 btree_node_unlock(trans, path, plevel);
885 static noinline int btree_node_iter_and_journal_peek(struct btree_trans *trans,
886 struct btree_path *path,
888 struct bkey_buf *out)
890 struct bch_fs *c = trans->c;
891 struct btree_path_level *l = path_l(path);
892 struct btree_and_journal_iter jiter;
896 __bch2_btree_and_journal_iter_init_node_iter(&jiter, c, l->b, l->iter, path->pos);
898 k = bch2_btree_and_journal_iter_peek(&jiter);
900 bch2_bkey_buf_reassemble(out, c, k);
902 if (flags & BTREE_ITER_PREFETCH)
903 ret = btree_path_prefetch_j(trans, path, &jiter);
905 bch2_btree_and_journal_iter_exit(&jiter);
909 static __always_inline int btree_path_down(struct btree_trans *trans,
910 struct btree_path *path,
912 unsigned long trace_ip)
914 struct bch_fs *c = trans->c;
915 struct btree_path_level *l = path_l(path);
917 unsigned level = path->level - 1;
918 enum six_lock_type lock_type = __btree_lock_want(path, level);
922 EBUG_ON(!btree_node_locked(path, path->level));
924 bch2_bkey_buf_init(&tmp);
926 if (unlikely(trans->journal_replay_not_finished)) {
927 ret = btree_node_iter_and_journal_peek(trans, path, flags, &tmp);
931 bch2_bkey_buf_unpack(&tmp, c, l->b,
932 bch2_btree_node_iter_peek(&l->iter, l->b));
934 if (flags & BTREE_ITER_PREFETCH) {
935 ret = btree_path_prefetch(trans, path);
941 b = bch2_btree_node_get(trans, path, tmp.k, level, lock_type, trace_ip);
942 ret = PTR_ERR_OR_ZERO(b);
946 if (likely(!trans->journal_replay_not_finished &&
947 tmp.k->k.type == KEY_TYPE_btree_ptr_v2) &&
948 unlikely(b != btree_node_mem_ptr(tmp.k)))
949 btree_node_mem_ptr_set(trans, path, level + 1, b);
951 if (btree_node_read_locked(path, level + 1))
952 btree_node_unlock(trans, path, level + 1);
954 mark_btree_node_locked(trans, path, level, lock_type);
956 bch2_btree_path_level_init(trans, path, b);
958 bch2_btree_path_verify_locks(path);
960 bch2_bkey_buf_exit(&tmp, c);
965 static int bch2_btree_path_traverse_all(struct btree_trans *trans)
967 struct bch_fs *c = trans->c;
968 struct btree_path *path;
969 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)
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(c, &cl);
999 /* Now, redo traversals in correct order: */
1001 while (i < trans->nr_sorted) {
1002 path = trans->paths + trans->sorted[i];
1005 * Traversing a path can cause another path to be added at about
1006 * the same position:
1008 if (path->uptodate) {
1009 __btree_path_get(path, false);
1010 ret = bch2_btree_path_traverse_one(trans, path, 0, _THIS_IP_);
1011 __btree_path_put(path, 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 we might have unlocked and
1027 * then failed to relock a path - that's fine.
1030 bch2_btree_cache_cannibalize_unlock(c);
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 struct btree_path *path,
1118 unsigned long trace_ip)
1120 unsigned depth_want = path->level;
1121 int ret = -((int) trans->restarted);
1127 * Ensure we obey path->should_be_locked: if it's set, we can't unlock
1128 * and re-traverse the path without a transaction restart:
1130 if (path->should_be_locked) {
1131 ret = bch2_btree_path_relock(trans, path, trace_ip);
1136 ret = bch2_btree_path_traverse_cached(trans, path, flags);
1140 if (unlikely(path->level >= BTREE_MAX_DEPTH))
1143 path->level = btree_path_up_until_good_node(trans, path, 0);
1145 EBUG_ON(btree_path_node(path, path->level) &&
1146 !btree_node_locked(path, path->level));
1149 * Note: path->nodes[path->level] may be temporarily NULL here - that
1150 * would indicate to other code that we got to the end of the btree,
1151 * here it indicates that relocking the root failed - it's critical that
1152 * btree_path_lock_root() comes next and that it can't fail
1154 while (path->level > depth_want) {
1155 ret = btree_path_node(path, path->level)
1156 ? btree_path_down(trans, path, flags, trace_ip)
1157 : btree_path_lock_root(trans, path, depth_want, trace_ip);
1158 if (unlikely(ret)) {
1161 * No nodes at this level - got to the end of
1168 __bch2_btree_path_unlock(trans, path);
1169 path->level = depth_want;
1170 path->l[path->level].b = ERR_PTR(ret);
1175 path->uptodate = BTREE_ITER_UPTODATE;
1177 if (bch2_err_matches(ret, BCH_ERR_transaction_restart) != !!trans->restarted)
1178 panic("ret %s (%i) trans->restarted %s (%i)\n",
1179 bch2_err_str(ret), ret,
1180 bch2_err_str(trans->restarted), trans->restarted);
1181 bch2_btree_path_verify(trans, path);
1185 static inline void btree_path_copy(struct btree_trans *trans, struct btree_path *dst,
1186 struct btree_path *src)
1188 unsigned i, offset = offsetof(struct btree_path, pos);
1190 memcpy((void *) dst + offset,
1191 (void *) src + offset,
1192 sizeof(struct btree_path) - offset);
1194 for (i = 0; i < BTREE_MAX_DEPTH; i++) {
1195 unsigned t = btree_node_locked_type(dst, i);
1197 if (t != BTREE_NODE_UNLOCKED)
1198 six_lock_increment(&dst->l[i].b->c.lock, t);
1202 static struct btree_path *btree_path_clone(struct btree_trans *trans, struct btree_path *src,
1205 struct btree_path *new = btree_path_alloc(trans, src);
1207 btree_path_copy(trans, new, src);
1208 __btree_path_get(new, intent);
1213 struct btree_path *__bch2_btree_path_make_mut(struct btree_trans *trans,
1214 struct btree_path *path, bool intent,
1217 __btree_path_put(path, intent);
1218 path = btree_path_clone(trans, path, intent);
1219 path->preserve = false;
1223 struct btree_path * __must_check
1224 __bch2_btree_path_set_pos(struct btree_trans *trans,
1225 struct btree_path *path, struct bpos new_pos,
1226 bool intent, unsigned long ip, int cmp)
1228 unsigned level = path->level;
1230 bch2_trans_verify_not_in_restart(trans);
1231 EBUG_ON(!path->ref);
1233 path = bch2_btree_path_make_mut(trans, path, intent, ip);
1235 path->pos = new_pos;
1236 trans->paths_sorted = false;
1238 if (unlikely(path->cached)) {
1239 btree_node_unlock(trans, path, 0);
1240 path->l[0].b = ERR_PTR(-BCH_ERR_no_btree_node_up);
1241 btree_path_set_dirty(path, BTREE_ITER_NEED_TRAVERSE);
1245 level = btree_path_up_until_good_node(trans, path, cmp);
1247 if (btree_path_node(path, level)) {
1248 struct btree_path_level *l = &path->l[level];
1250 BUG_ON(!btree_node_locked(path, level));
1252 * We might have to skip over many keys, or just a few: try
1253 * advancing the node iterator, and if we have to skip over too
1254 * many keys just reinit it (or if we're rewinding, since that
1258 !btree_path_advance_to_pos(path, l, 8))
1259 bch2_btree_node_iter_init(&l->iter, l->b, &path->pos);
1262 * Iterators to interior nodes should always be pointed at the first non
1265 if (unlikely(level))
1266 bch2_btree_node_iter_peek(&l->iter, l->b);
1269 if (unlikely(level != path->level)) {
1270 btree_path_set_dirty(path, BTREE_ITER_NEED_TRAVERSE);
1271 __bch2_btree_path_unlock(trans, path);
1274 bch2_btree_path_verify(trans, path);
1278 /* Btree path: main interface: */
1280 static struct btree_path *have_path_at_pos(struct btree_trans *trans, struct btree_path *path)
1282 struct btree_path *sib;
1284 sib = prev_btree_path(trans, path);
1285 if (sib && !btree_path_cmp(sib, path))
1288 sib = next_btree_path(trans, path);
1289 if (sib && !btree_path_cmp(sib, path))
1295 static struct btree_path *have_node_at_pos(struct btree_trans *trans, struct btree_path *path)
1297 struct btree_path *sib;
1299 sib = prev_btree_path(trans, path);
1300 if (sib && sib->level == path->level && path_l(sib)->b == path_l(path)->b)
1303 sib = next_btree_path(trans, path);
1304 if (sib && sib->level == path->level && path_l(sib)->b == path_l(path)->b)
1310 static inline void __bch2_path_free(struct btree_trans *trans, struct btree_path *path)
1312 __bch2_btree_path_unlock(trans, path);
1313 btree_path_list_remove(trans, path);
1314 trans->paths_allocated &= ~(1ULL << path->idx);
1317 void bch2_path_put(struct btree_trans *trans, struct btree_path *path, bool intent)
1319 struct btree_path *dup;
1321 EBUG_ON(trans->paths + path->idx != path);
1322 EBUG_ON(!path->ref);
1324 if (!__btree_path_put(path, intent))
1327 dup = path->preserve
1328 ? have_path_at_pos(trans, path)
1329 : have_node_at_pos(trans, path);
1331 if (!dup && !(!path->preserve && !is_btree_node(path, path->level)))
1334 if (path->should_be_locked &&
1335 !trans->restarted &&
1336 (!dup || !bch2_btree_path_relock_norestart(trans, dup, _THIS_IP_)))
1340 dup->preserve |= path->preserve;
1341 dup->should_be_locked |= path->should_be_locked;
1344 __bch2_path_free(trans, path);
1347 static void bch2_path_put_nokeep(struct btree_trans *trans, struct btree_path *path,
1350 EBUG_ON(trans->paths + path->idx != path);
1351 EBUG_ON(!path->ref);
1353 if (!__btree_path_put(path, intent))
1356 __bch2_path_free(trans, path);
1359 void 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 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 struct btree_insert_entry *i;
1377 struct btree_write_buffered_key *wb;
1379 prt_printf(buf, "transaction updates for %s journal seq %llu",
1380 trans->fn, trans->journal_res.seq);
1382 printbuf_indent_add(buf, 2);
1384 trans_for_each_update(trans, i) {
1385 struct bkey_s_c old = { &i->old_k, i->old_v };
1387 prt_printf(buf, "update: btree=%s cached=%u %pS",
1388 bch2_btree_ids[i->btree_id],
1390 (void *) i->ip_allocated);
1393 prt_printf(buf, " old ");
1394 bch2_bkey_val_to_text(buf, trans->c, old);
1397 prt_printf(buf, " new ");
1398 bch2_bkey_val_to_text(buf, trans->c, bkey_i_to_s_c(i->k));
1402 trans_for_each_wb_update(trans, wb) {
1403 prt_printf(buf, "update: btree=%s wb=1 %pS",
1404 bch2_btree_ids[wb->btree],
1405 (void *) i->ip_allocated);
1408 prt_printf(buf, " new ");
1409 bch2_bkey_val_to_text(buf, trans->c, bkey_i_to_s_c(&wb->k));
1413 printbuf_indent_sub(buf, 2);
1417 void bch2_dump_trans_updates(struct btree_trans *trans)
1419 struct printbuf buf = PRINTBUF;
1421 bch2_trans_updates_to_text(&buf, trans);
1422 bch2_print_string_as_lines(KERN_ERR, buf.buf);
1423 printbuf_exit(&buf);
1427 void bch2_btree_path_to_text(struct printbuf *out, struct btree_path *path)
1429 prt_printf(out, "path: idx %2u ref %u:%u %c %c btree=%s l=%u pos ",
1430 path->idx, path->ref, path->intent_ref,
1431 path->preserve ? 'P' : ' ',
1432 path->should_be_locked ? 'S' : ' ',
1433 bch2_btree_ids[path->btree_id],
1435 bch2_bpos_to_text(out, path->pos);
1437 prt_printf(out, " locks %u", path->nodes_locked);
1438 #ifdef TRACK_PATH_ALLOCATED
1439 prt_printf(out, " %pS", (void *) path->ip_allocated);
1445 void __bch2_trans_paths_to_text(struct printbuf *out, struct btree_trans *trans,
1448 struct btree_path *path;
1452 btree_trans_sort_paths(trans);
1454 trans_for_each_path_inorder(trans, path, idx)
1455 bch2_btree_path_to_text(out, path);
1459 void bch2_trans_paths_to_text(struct printbuf *out, struct btree_trans *trans)
1461 __bch2_trans_paths_to_text(out, trans, false);
1465 void __bch2_dump_trans_paths_updates(struct btree_trans *trans, bool nosort)
1467 struct printbuf buf = PRINTBUF;
1469 __bch2_trans_paths_to_text(&buf, trans, nosort);
1470 bch2_trans_updates_to_text(&buf, trans);
1472 bch2_print_string_as_lines(KERN_ERR, buf.buf);
1473 printbuf_exit(&buf);
1477 void bch2_dump_trans_paths_updates(struct btree_trans *trans)
1479 __bch2_dump_trans_paths_updates(trans, false);
1483 static void bch2_trans_update_max_paths(struct btree_trans *trans)
1485 struct btree_transaction_stats *s = btree_trans_stats(trans);
1486 struct printbuf buf = PRINTBUF;
1491 bch2_trans_paths_to_text(&buf, trans);
1493 if (!buf.allocation_failure) {
1494 mutex_lock(&s->lock);
1495 if (s->nr_max_paths < hweight64(trans->paths_allocated)) {
1496 s->nr_max_paths = trans->nr_max_paths =
1497 hweight64(trans->paths_allocated);
1498 swap(s->max_paths_text, buf.buf);
1500 mutex_unlock(&s->lock);
1503 printbuf_exit(&buf);
1505 trans->nr_max_paths = hweight64(trans->paths_allocated);
1508 static noinline void btree_path_overflow(struct btree_trans *trans)
1510 bch2_dump_trans_paths_updates(trans);
1511 panic("trans path oveflow\n");
1514 static inline struct btree_path *btree_path_alloc(struct btree_trans *trans,
1515 struct btree_path *pos)
1517 struct btree_path *path;
1520 if (unlikely(trans->paths_allocated ==
1521 ~((~0ULL << 1) << (BTREE_ITER_MAX - 1))))
1522 btree_path_overflow(trans);
1524 idx = __ffs64(~trans->paths_allocated);
1527 * Do this before marking the new path as allocated, since it won't be
1530 if (unlikely(idx > trans->nr_max_paths))
1531 bch2_trans_update_max_paths(trans);
1533 trans->paths_allocated |= 1ULL << idx;
1535 path = &trans->paths[idx];
1538 path->intent_ref = 0;
1539 path->nodes_locked = 0;
1541 btree_path_list_add(trans, pos, path);
1542 trans->paths_sorted = false;
1546 struct btree_path *bch2_path_get(struct btree_trans *trans,
1547 enum btree_id btree_id, struct bpos pos,
1548 unsigned locks_want, unsigned level,
1549 unsigned flags, unsigned long ip)
1551 struct btree_path *path, *path_pos = NULL;
1552 bool cached = flags & BTREE_ITER_CACHED;
1553 bool intent = flags & BTREE_ITER_INTENT;
1556 bch2_trans_verify_not_in_restart(trans);
1557 bch2_trans_verify_locks(trans);
1559 btree_trans_sort_paths(trans);
1561 trans_for_each_path_inorder(trans, path, i) {
1562 if (__btree_path_cmp(path,
1573 path_pos->cached == cached &&
1574 path_pos->btree_id == btree_id &&
1575 path_pos->level == level) {
1576 __btree_path_get(path_pos, intent);
1577 path = bch2_btree_path_set_pos(trans, path_pos, pos, intent, ip);
1579 path = btree_path_alloc(trans, path_pos);
1582 __btree_path_get(path, intent);
1584 path->btree_id = btree_id;
1585 path->cached = cached;
1586 path->uptodate = BTREE_ITER_NEED_TRAVERSE;
1587 path->should_be_locked = false;
1588 path->level = level;
1589 path->locks_want = locks_want;
1590 path->nodes_locked = 0;
1591 for (i = 0; i < ARRAY_SIZE(path->l); i++)
1592 path->l[i].b = ERR_PTR(-BCH_ERR_no_btree_node_init);
1593 #ifdef TRACK_PATH_ALLOCATED
1594 path->ip_allocated = ip;
1596 trans->paths_sorted = false;
1599 if (!(flags & BTREE_ITER_NOPRESERVE))
1600 path->preserve = true;
1602 if (path->intent_ref)
1603 locks_want = max(locks_want, level + 1);
1606 * If the path has locks_want greater than requested, we don't downgrade
1607 * it here - on transaction restart because btree node split needs to
1608 * upgrade locks, we might be putting/getting the iterator again.
1609 * Downgrading iterators only happens via bch2_trans_downgrade(), after
1610 * a successful transaction commit.
1613 locks_want = min(locks_want, BTREE_MAX_DEPTH);
1614 if (locks_want > path->locks_want)
1615 bch2_btree_path_upgrade_noupgrade_sibs(trans, path, locks_want);
1620 struct bkey_s_c bch2_btree_path_peek_slot(struct btree_path *path, struct bkey *u)
1623 struct btree_path_level *l = path_l(path);
1624 struct bkey_packed *_k;
1627 if (unlikely(!l->b))
1628 return bkey_s_c_null;
1630 EBUG_ON(path->uptodate != BTREE_ITER_UPTODATE);
1631 EBUG_ON(!btree_node_locked(path, path->level));
1633 if (!path->cached) {
1634 _k = bch2_btree_node_iter_peek_all(&l->iter, l->b);
1635 k = _k ? bkey_disassemble(l->b, _k, u) : bkey_s_c_null;
1637 EBUG_ON(k.k && bkey_deleted(k.k) && bpos_eq(k.k->p, path->pos));
1639 if (!k.k || !bpos_eq(path->pos, k.k->p))
1642 struct bkey_cached *ck = (void *) path->l[0].b;
1645 (path->btree_id != ck->key.btree_id ||
1646 !bkey_eq(path->pos, ck->key.pos)));
1647 if (!ck || !ck->valid)
1648 return bkey_s_c_null;
1651 k = bkey_i_to_s_c(ck->k);
1658 return (struct bkey_s_c) { u, NULL };
1661 /* Btree iterators: */
1664 __bch2_btree_iter_traverse(struct btree_iter *iter)
1666 return bch2_btree_path_traverse(iter->trans, iter->path, iter->flags);
1670 bch2_btree_iter_traverse(struct btree_iter *iter)
1674 iter->path = bch2_btree_path_set_pos(iter->trans, iter->path,
1675 btree_iter_search_key(iter),
1676 iter->flags & BTREE_ITER_INTENT,
1677 btree_iter_ip_allocated(iter));
1679 ret = bch2_btree_path_traverse(iter->trans, iter->path, iter->flags);
1683 btree_path_set_should_be_locked(iter->path);
1687 /* Iterate across nodes (leaf and interior nodes) */
1689 struct btree *bch2_btree_iter_peek_node(struct btree_iter *iter)
1691 struct btree_trans *trans = iter->trans;
1692 struct btree *b = NULL;
1695 EBUG_ON(iter->path->cached);
1696 bch2_btree_iter_verify(iter);
1698 ret = bch2_btree_path_traverse(trans, iter->path, iter->flags);
1702 b = btree_path_node(iter->path, iter->path->level);
1706 BUG_ON(bpos_lt(b->key.k.p, iter->pos));
1708 bkey_init(&iter->k);
1709 iter->k.p = iter->pos = b->key.k.p;
1711 iter->path = bch2_btree_path_set_pos(trans, iter->path, b->key.k.p,
1712 iter->flags & BTREE_ITER_INTENT,
1713 btree_iter_ip_allocated(iter));
1714 btree_path_set_should_be_locked(iter->path);
1716 bch2_btree_iter_verify_entry_exit(iter);
1717 bch2_btree_iter_verify(iter);
1725 struct btree *bch2_btree_iter_peek_node_and_restart(struct btree_iter *iter)
1729 while (b = bch2_btree_iter_peek_node(iter),
1730 bch2_err_matches(PTR_ERR_OR_ZERO(b), BCH_ERR_transaction_restart))
1731 bch2_trans_begin(iter->trans);
1736 struct btree *bch2_btree_iter_next_node(struct btree_iter *iter)
1738 struct btree_trans *trans = iter->trans;
1739 struct btree_path *path = iter->path;
1740 struct btree *b = NULL;
1743 bch2_trans_verify_not_in_restart(trans);
1744 EBUG_ON(iter->path->cached);
1745 bch2_btree_iter_verify(iter);
1747 /* already at end? */
1748 if (!btree_path_node(path, path->level))
1752 if (!btree_path_node(path, path->level + 1)) {
1753 btree_path_set_level_up(trans, path);
1757 if (!bch2_btree_node_relock(trans, path, path->level + 1)) {
1758 __bch2_btree_path_unlock(trans, path);
1759 path->l[path->level].b = ERR_PTR(-BCH_ERR_no_btree_node_relock);
1760 path->l[path->level + 1].b = ERR_PTR(-BCH_ERR_no_btree_node_relock);
1761 btree_path_set_dirty(path, BTREE_ITER_NEED_TRAVERSE);
1762 trace_and_count(trans->c, trans_restart_relock_next_node, trans, _THIS_IP_, path);
1763 ret = btree_trans_restart(trans, BCH_ERR_transaction_restart_relock);
1767 b = btree_path_node(path, path->level + 1);
1769 if (bpos_eq(iter->pos, b->key.k.p)) {
1770 __btree_path_set_level_up(trans, path, path->level++);
1773 * Haven't gotten to the end of the parent node: go back down to
1774 * the next child node
1777 bch2_btree_path_set_pos(trans, path, bpos_successor(iter->pos),
1778 iter->flags & BTREE_ITER_INTENT,
1779 btree_iter_ip_allocated(iter));
1781 btree_path_set_level_down(trans, path, iter->min_depth);
1783 ret = bch2_btree_path_traverse(trans, path, iter->flags);
1787 b = path->l[path->level].b;
1790 bkey_init(&iter->k);
1791 iter->k.p = iter->pos = b->key.k.p;
1793 iter->path = bch2_btree_path_set_pos(trans, iter->path, b->key.k.p,
1794 iter->flags & BTREE_ITER_INTENT,
1795 btree_iter_ip_allocated(iter));
1796 btree_path_set_should_be_locked(iter->path);
1797 BUG_ON(iter->path->uptodate);
1799 bch2_btree_iter_verify_entry_exit(iter);
1800 bch2_btree_iter_verify(iter);
1808 /* Iterate across keys (in leaf nodes only) */
1810 inline bool bch2_btree_iter_advance(struct btree_iter *iter)
1812 if (likely(!(iter->flags & BTREE_ITER_ALL_LEVELS))) {
1813 struct bpos pos = iter->k.p;
1814 bool ret = !(iter->flags & BTREE_ITER_ALL_SNAPSHOTS
1815 ? bpos_eq(pos, SPOS_MAX)
1816 : bkey_eq(pos, SPOS_MAX));
1818 if (ret && !(iter->flags & BTREE_ITER_IS_EXTENTS))
1819 pos = bkey_successor(iter, pos);
1820 bch2_btree_iter_set_pos(iter, pos);
1823 if (!btree_path_node(iter->path, iter->path->level))
1826 iter->advanced = true;
1831 inline bool bch2_btree_iter_rewind(struct btree_iter *iter)
1833 struct bpos pos = bkey_start_pos(&iter->k);
1834 bool ret = !(iter->flags & BTREE_ITER_ALL_SNAPSHOTS
1835 ? bpos_eq(pos, POS_MIN)
1836 : bkey_eq(pos, POS_MIN));
1838 if (ret && !(iter->flags & BTREE_ITER_IS_EXTENTS))
1839 pos = bkey_predecessor(iter, pos);
1840 bch2_btree_iter_set_pos(iter, pos);
1845 struct bkey_i *__bch2_btree_trans_peek_updates(struct btree_iter *iter)
1847 struct btree_insert_entry *i;
1848 struct bkey_i *ret = NULL;
1850 trans_for_each_update(iter->trans, i) {
1851 if (i->btree_id < iter->btree_id)
1853 if (i->btree_id > iter->btree_id)
1855 if (bpos_lt(i->k->k.p, iter->path->pos))
1857 if (i->key_cache_already_flushed)
1859 if (!ret || bpos_lt(i->k->k.p, ret->k.p))
1866 static inline struct bkey_i *btree_trans_peek_updates(struct btree_iter *iter)
1868 return iter->flags & BTREE_ITER_WITH_UPDATES
1869 ? __bch2_btree_trans_peek_updates(iter)
1873 struct bkey_i *bch2_btree_journal_peek(struct btree_trans *trans,
1874 struct btree_iter *iter,
1875 struct bpos end_pos)
1879 if (bpos_lt(iter->path->pos, iter->journal_pos))
1880 iter->journal_idx = 0;
1882 k = bch2_journal_keys_peek_upto(trans->c, iter->btree_id,
1886 &iter->journal_idx);
1888 iter->journal_pos = k ? k->k.p : end_pos;
1893 struct bkey_s_c btree_trans_peek_slot_journal(struct btree_trans *trans,
1894 struct btree_iter *iter)
1896 struct bkey_i *k = bch2_btree_journal_peek(trans, iter, iter->path->pos);
1900 return bkey_i_to_s_c(k);
1902 return bkey_s_c_null;
1907 struct bkey_s_c btree_trans_peek_journal(struct btree_trans *trans,
1908 struct btree_iter *iter,
1911 struct bkey_i *next_journal =
1912 bch2_btree_journal_peek(trans, iter,
1913 k.k ? k.k->p : path_l(iter->path)->b->key.k.p);
1916 iter->k = next_journal->k;
1917 k = bkey_i_to_s_c(next_journal);
1924 * Checks btree key cache for key at iter->pos and returns it if present, or
1928 struct bkey_s_c btree_trans_peek_key_cache(struct btree_iter *iter, struct bpos pos)
1930 struct btree_trans *trans = iter->trans;
1931 struct bch_fs *c = trans->c;
1936 if ((iter->flags & BTREE_ITER_KEY_CACHE_FILL) &&
1937 bpos_eq(iter->pos, pos))
1938 return bkey_s_c_null;
1940 if (!bch2_btree_key_cache_find(c, iter->btree_id, pos))
1941 return bkey_s_c_null;
1943 if (!iter->key_cache_path)
1944 iter->key_cache_path = bch2_path_get(trans, iter->btree_id, pos,
1945 iter->flags & BTREE_ITER_INTENT, 0,
1946 iter->flags|BTREE_ITER_CACHED|
1947 BTREE_ITER_CACHED_NOFILL,
1950 iter->key_cache_path = bch2_btree_path_set_pos(trans, iter->key_cache_path, pos,
1951 iter->flags & BTREE_ITER_INTENT,
1952 btree_iter_ip_allocated(iter));
1954 ret = bch2_btree_path_traverse(trans, iter->key_cache_path,
1955 iter->flags|BTREE_ITER_CACHED) ?:
1956 bch2_btree_path_relock(trans, iter->path, _THIS_IP_);
1958 return bkey_s_c_err(ret);
1960 btree_path_set_should_be_locked(iter->key_cache_path);
1962 k = bch2_btree_path_peek_slot(iter->key_cache_path, &u);
1963 if (k.k && !bkey_err(k)) {
1970 static struct bkey_s_c __bch2_btree_iter_peek(struct btree_iter *iter, struct bpos search_key)
1972 struct btree_trans *trans = iter->trans;
1973 struct bkey_i *next_update;
1974 struct bkey_s_c k, k2;
1977 EBUG_ON(iter->path->cached);
1978 bch2_btree_iter_verify(iter);
1981 struct btree_path_level *l;
1983 iter->path = bch2_btree_path_set_pos(trans, iter->path, search_key,
1984 iter->flags & BTREE_ITER_INTENT,
1985 btree_iter_ip_allocated(iter));
1987 ret = bch2_btree_path_traverse(trans, iter->path, iter->flags);
1988 if (unlikely(ret)) {
1989 /* ensure that iter->k is consistent with iter->pos: */
1990 bch2_btree_iter_set_pos(iter, iter->pos);
1991 k = bkey_s_c_err(ret);
1995 l = path_l(iter->path);
1997 if (unlikely(!l->b)) {
1998 /* No btree nodes at requested level: */
1999 bch2_btree_iter_set_pos(iter, SPOS_MAX);
2004 btree_path_set_should_be_locked(iter->path);
2006 k = btree_path_level_peek_all(trans->c, l, &iter->k);
2008 if (unlikely(iter->flags & BTREE_ITER_WITH_KEY_CACHE) &&
2010 (k2 = btree_trans_peek_key_cache(iter, k.k->p)).k) {
2014 bch2_btree_iter_set_pos(iter, iter->pos);
2019 if (unlikely(iter->flags & BTREE_ITER_WITH_JOURNAL))
2020 k = btree_trans_peek_journal(trans, iter, k);
2022 next_update = btree_trans_peek_updates(iter);
2025 bpos_le(next_update->k.p,
2026 k.k ? k.k->p : l->b->key.k.p)) {
2027 iter->k = next_update->k;
2028 k = bkey_i_to_s_c(next_update);
2031 if (k.k && bkey_deleted(k.k)) {
2033 * If we've got a whiteout, and it's after the search
2034 * key, advance the search key to the whiteout instead
2035 * of just after the whiteout - it might be a btree
2036 * whiteout, with a real key at the same position, since
2037 * in the btree deleted keys sort before non deleted.
2039 search_key = !bpos_eq(search_key, k.k->p)
2041 : bpos_successor(k.k->p);
2047 } else if (likely(!bpos_eq(l->b->key.k.p, SPOS_MAX))) {
2048 /* Advance to next leaf node: */
2049 search_key = bpos_successor(l->b->key.k.p);
2052 bch2_btree_iter_set_pos(iter, SPOS_MAX);
2058 bch2_btree_iter_verify(iter);
2064 * bch2_btree_iter_peek: returns first key greater than or equal to iterator's
2067 struct bkey_s_c bch2_btree_iter_peek_upto(struct btree_iter *iter, struct bpos end)
2069 struct btree_trans *trans = iter->trans;
2070 struct bpos search_key = btree_iter_search_key(iter);
2072 struct bpos iter_pos;
2075 EBUG_ON(iter->flags & BTREE_ITER_ALL_LEVELS);
2076 EBUG_ON((iter->flags & BTREE_ITER_FILTER_SNAPSHOTS) && bkey_eq(end, POS_MAX));
2078 if (iter->update_path) {
2079 bch2_path_put_nokeep(trans, iter->update_path,
2080 iter->flags & BTREE_ITER_INTENT);
2081 iter->update_path = NULL;
2084 bch2_btree_iter_verify_entry_exit(iter);
2087 k = __bch2_btree_iter_peek(iter, search_key);
2090 if (unlikely(bkey_err(k)))
2094 * iter->pos should be mononotically increasing, and always be
2095 * equal to the key we just returned - except extents can
2096 * straddle iter->pos:
2098 if (!(iter->flags & BTREE_ITER_IS_EXTENTS))
2101 iter_pos = bkey_max(iter->pos, bkey_start_pos(k.k));
2103 if (unlikely(!(iter->flags & BTREE_ITER_IS_EXTENTS)
2104 ? bkey_gt(iter_pos, end)
2105 : bkey_ge(iter_pos, end)))
2108 if (iter->update_path &&
2109 !bkey_eq(iter->update_path->pos, k.k->p)) {
2110 bch2_path_put_nokeep(trans, iter->update_path,
2111 iter->flags & BTREE_ITER_INTENT);
2112 iter->update_path = NULL;
2115 if ((iter->flags & BTREE_ITER_FILTER_SNAPSHOTS) &&
2116 (iter->flags & BTREE_ITER_INTENT) &&
2117 !(iter->flags & BTREE_ITER_IS_EXTENTS) &&
2118 !iter->update_path) {
2119 struct bpos pos = k.k->p;
2121 if (pos.snapshot < iter->snapshot) {
2122 search_key = bpos_successor(k.k->p);
2126 pos.snapshot = iter->snapshot;
2129 * advance, same as on exit for iter->path, but only up
2132 __btree_path_get(iter->path, iter->flags & BTREE_ITER_INTENT);
2133 iter->update_path = iter->path;
2135 iter->update_path = bch2_btree_path_set_pos(trans,
2136 iter->update_path, pos,
2137 iter->flags & BTREE_ITER_INTENT,
2139 ret = bch2_btree_path_traverse(trans, iter->update_path, iter->flags);
2140 if (unlikely(ret)) {
2141 k = bkey_s_c_err(ret);
2147 * We can never have a key in a leaf node at POS_MAX, so
2148 * we don't have to check these successor() calls:
2150 if ((iter->flags & BTREE_ITER_FILTER_SNAPSHOTS) &&
2151 !bch2_snapshot_is_ancestor(trans->c,
2154 search_key = bpos_successor(k.k->p);
2158 if (bkey_whiteout(k.k) &&
2159 !(iter->flags & BTREE_ITER_ALL_SNAPSHOTS)) {
2160 search_key = bkey_successor(iter, k.k->p);
2167 iter->pos = iter_pos;
2169 iter->path = bch2_btree_path_set_pos(trans, iter->path, k.k->p,
2170 iter->flags & BTREE_ITER_INTENT,
2171 btree_iter_ip_allocated(iter));
2173 btree_path_set_should_be_locked(iter->path);
2175 if (iter->update_path) {
2176 ret = bch2_btree_path_relock(trans, iter->update_path, _THIS_IP_);
2178 k = bkey_s_c_err(ret);
2180 btree_path_set_should_be_locked(iter->update_path);
2183 if (!(iter->flags & BTREE_ITER_ALL_SNAPSHOTS))
2184 iter->pos.snapshot = iter->snapshot;
2186 ret = bch2_btree_iter_verify_ret(iter, k);
2187 if (unlikely(ret)) {
2188 bch2_btree_iter_set_pos(iter, iter->pos);
2189 k = bkey_s_c_err(ret);
2192 bch2_btree_iter_verify_entry_exit(iter);
2196 bch2_btree_iter_set_pos(iter, end);
2202 * bch2_btree_iter_peek_all_levels: returns the first key greater than or equal
2203 * to iterator's current position, returning keys from every level of the btree.
2204 * For keys at different levels of the btree that compare equal, the key from
2205 * the lower level (leaf) is returned first.
2207 struct bkey_s_c bch2_btree_iter_peek_all_levels(struct btree_iter *iter)
2209 struct btree_trans *trans = iter->trans;
2213 EBUG_ON(iter->path->cached);
2214 bch2_btree_iter_verify(iter);
2215 BUG_ON(iter->path->level < iter->min_depth);
2216 BUG_ON(!(iter->flags & BTREE_ITER_ALL_SNAPSHOTS));
2217 EBUG_ON(!(iter->flags & BTREE_ITER_ALL_LEVELS));
2220 iter->path = bch2_btree_path_set_pos(trans, iter->path, iter->pos,
2221 iter->flags & BTREE_ITER_INTENT,
2222 btree_iter_ip_allocated(iter));
2224 ret = bch2_btree_path_traverse(trans, iter->path, iter->flags);
2225 if (unlikely(ret)) {
2226 /* ensure that iter->k is consistent with iter->pos: */
2227 bch2_btree_iter_set_pos(iter, iter->pos);
2228 k = bkey_s_c_err(ret);
2232 /* Already at end? */
2233 if (!btree_path_node(iter->path, iter->path->level)) {
2238 k = btree_path_level_peek_all(trans->c,
2239 &iter->path->l[iter->path->level], &iter->k);
2241 /* Check if we should go up to the parent node: */
2244 bpos_eq(path_l(iter->path)->b->key.k.p, iter->pos))) {
2245 iter->pos = path_l(iter->path)->b->key.k.p;
2246 btree_path_set_level_up(trans, iter->path);
2247 iter->advanced = false;
2252 * Check if we should go back down to a leaf:
2253 * If we're not in a leaf node, we only return the current key
2254 * if it exactly matches iter->pos - otherwise we first have to
2255 * go back to the leaf:
2257 if (iter->path->level != iter->min_depth &&
2260 !bpos_eq(iter->pos, k.k->p))) {
2261 btree_path_set_level_down(trans, iter->path, iter->min_depth);
2262 iter->pos = bpos_successor(iter->pos);
2263 iter->advanced = false;
2267 /* Check if we should go to the next key: */
2268 if (iter->path->level == iter->min_depth &&
2271 bpos_eq(iter->pos, k.k->p)) {
2272 iter->pos = bpos_successor(iter->pos);
2273 iter->advanced = false;
2277 if (iter->advanced &&
2278 iter->path->level == iter->min_depth &&
2279 !bpos_eq(k.k->p, iter->pos))
2280 iter->advanced = false;
2282 BUG_ON(iter->advanced);
2288 btree_path_set_should_be_locked(iter->path);
2290 bch2_btree_iter_verify(iter);
2296 * bch2_btree_iter_next: returns first key greater than iterator's current
2299 struct bkey_s_c bch2_btree_iter_next(struct btree_iter *iter)
2301 if (!bch2_btree_iter_advance(iter))
2302 return bkey_s_c_null;
2304 return bch2_btree_iter_peek(iter);
2308 * bch2_btree_iter_peek_prev: returns first key less than or equal to
2309 * iterator's current position
2311 struct bkey_s_c bch2_btree_iter_peek_prev(struct btree_iter *iter)
2313 struct btree_trans *trans = iter->trans;
2314 struct bpos search_key = iter->pos;
2315 struct btree_path *saved_path = NULL;
2317 struct bkey saved_k;
2318 const struct bch_val *saved_v;
2321 EBUG_ON(iter->path->cached || iter->path->level);
2322 EBUG_ON(iter->flags & BTREE_ITER_WITH_UPDATES);
2324 if (iter->flags & BTREE_ITER_WITH_JOURNAL)
2325 return bkey_s_c_err(-EIO);
2327 bch2_btree_iter_verify(iter);
2328 bch2_btree_iter_verify_entry_exit(iter);
2330 if (iter->flags & BTREE_ITER_FILTER_SNAPSHOTS)
2331 search_key.snapshot = U32_MAX;
2334 iter->path = bch2_btree_path_set_pos(trans, iter->path, search_key,
2335 iter->flags & BTREE_ITER_INTENT,
2336 btree_iter_ip_allocated(iter));
2338 ret = bch2_btree_path_traverse(trans, iter->path, iter->flags);
2339 if (unlikely(ret)) {
2340 /* ensure that iter->k is consistent with iter->pos: */
2341 bch2_btree_iter_set_pos(iter, iter->pos);
2342 k = bkey_s_c_err(ret);
2346 k = btree_path_level_peek(trans, iter->path,
2347 &iter->path->l[0], &iter->k);
2349 ((iter->flags & BTREE_ITER_IS_EXTENTS)
2350 ? bpos_ge(bkey_start_pos(k.k), search_key)
2351 : bpos_gt(k.k->p, search_key)))
2352 k = btree_path_level_prev(trans, iter->path,
2353 &iter->path->l[0], &iter->k);
2356 if (iter->flags & BTREE_ITER_FILTER_SNAPSHOTS) {
2357 if (k.k->p.snapshot == iter->snapshot)
2361 * If we have a saved candidate, and we're no
2362 * longer at the same _key_ (not pos), return
2365 if (saved_path && !bkey_eq(k.k->p, saved_k.p)) {
2366 bch2_path_put_nokeep(trans, iter->path,
2367 iter->flags & BTREE_ITER_INTENT);
2368 iter->path = saved_path;
2375 if (bch2_snapshot_is_ancestor(iter->trans->c,
2379 bch2_path_put_nokeep(trans, saved_path,
2380 iter->flags & BTREE_ITER_INTENT);
2381 saved_path = btree_path_clone(trans, iter->path,
2382 iter->flags & BTREE_ITER_INTENT);
2387 search_key = bpos_predecessor(k.k->p);
2391 if (bkey_whiteout(k.k) &&
2392 !(iter->flags & BTREE_ITER_ALL_SNAPSHOTS)) {
2393 search_key = bkey_predecessor(iter, k.k->p);
2394 if (iter->flags & BTREE_ITER_FILTER_SNAPSHOTS)
2395 search_key.snapshot = U32_MAX;
2400 } else if (likely(!bpos_eq(iter->path->l[0].b->data->min_key, POS_MIN))) {
2401 /* Advance to previous leaf node: */
2402 search_key = bpos_predecessor(iter->path->l[0].b->data->min_key);
2404 /* Start of btree: */
2405 bch2_btree_iter_set_pos(iter, POS_MIN);
2411 EBUG_ON(bkey_gt(bkey_start_pos(k.k), iter->pos));
2413 /* Extents can straddle iter->pos: */
2414 if (bkey_lt(k.k->p, iter->pos))
2417 if (iter->flags & BTREE_ITER_FILTER_SNAPSHOTS)
2418 iter->pos.snapshot = iter->snapshot;
2420 btree_path_set_should_be_locked(iter->path);
2423 bch2_path_put_nokeep(trans, saved_path, iter->flags & BTREE_ITER_INTENT);
2425 bch2_btree_iter_verify_entry_exit(iter);
2426 bch2_btree_iter_verify(iter);
2432 * bch2_btree_iter_prev: returns first key less than iterator's current
2435 struct bkey_s_c bch2_btree_iter_prev(struct btree_iter *iter)
2437 if (!bch2_btree_iter_rewind(iter))
2438 return bkey_s_c_null;
2440 return bch2_btree_iter_peek_prev(iter);
2443 struct bkey_s_c bch2_btree_iter_peek_slot(struct btree_iter *iter)
2445 struct btree_trans *trans = iter->trans;
2446 struct bpos search_key;
2450 bch2_btree_iter_verify(iter);
2451 bch2_btree_iter_verify_entry_exit(iter);
2452 EBUG_ON(iter->flags & BTREE_ITER_ALL_LEVELS);
2453 EBUG_ON(iter->path->level && (iter->flags & BTREE_ITER_WITH_KEY_CACHE));
2455 /* extents can't span inode numbers: */
2456 if ((iter->flags & BTREE_ITER_IS_EXTENTS) &&
2457 unlikely(iter->pos.offset == KEY_OFFSET_MAX)) {
2458 if (iter->pos.inode == KEY_INODE_MAX)
2459 return bkey_s_c_null;
2461 bch2_btree_iter_set_pos(iter, bpos_nosnap_successor(iter->pos));
2464 search_key = btree_iter_search_key(iter);
2465 iter->path = bch2_btree_path_set_pos(trans, iter->path, search_key,
2466 iter->flags & BTREE_ITER_INTENT,
2467 btree_iter_ip_allocated(iter));
2469 ret = bch2_btree_path_traverse(trans, iter->path, iter->flags);
2470 if (unlikely(ret)) {
2471 k = bkey_s_c_err(ret);
2475 if ((iter->flags & BTREE_ITER_CACHED) ||
2476 !(iter->flags & (BTREE_ITER_IS_EXTENTS|BTREE_ITER_FILTER_SNAPSHOTS))) {
2477 struct bkey_i *next_update;
2479 if ((next_update = btree_trans_peek_updates(iter)) &&
2480 bpos_eq(next_update->k.p, iter->pos)) {
2481 iter->k = next_update->k;
2482 k = bkey_i_to_s_c(next_update);
2486 if (unlikely(iter->flags & BTREE_ITER_WITH_JOURNAL) &&
2487 (k = btree_trans_peek_slot_journal(trans, iter)).k)
2490 if (unlikely(iter->flags & BTREE_ITER_WITH_KEY_CACHE) &&
2491 (k = btree_trans_peek_key_cache(iter, iter->pos)).k) {
2494 /* We're not returning a key from iter->path: */
2498 k = bch2_btree_path_peek_slot(iter->path, &iter->k);
2503 struct bpos end = iter->pos;
2505 if (iter->flags & BTREE_ITER_IS_EXTENTS)
2506 end.offset = U64_MAX;
2508 EBUG_ON(iter->path->level);
2510 if (iter->flags & BTREE_ITER_INTENT) {
2511 struct btree_iter iter2;
2513 bch2_trans_copy_iter(&iter2, iter);
2514 k = bch2_btree_iter_peek_upto(&iter2, end);
2516 if (k.k && !bkey_err(k)) {
2520 bch2_trans_iter_exit(trans, &iter2);
2522 struct bpos pos = iter->pos;
2524 k = bch2_btree_iter_peek_upto(iter, end);
2525 if (unlikely(bkey_err(k)))
2526 bch2_btree_iter_set_pos(iter, pos);
2531 if (unlikely(bkey_err(k)))
2534 next = k.k ? bkey_start_pos(k.k) : POS_MAX;
2536 if (bkey_lt(iter->pos, next)) {
2537 bkey_init(&iter->k);
2538 iter->k.p = iter->pos;
2540 if (iter->flags & BTREE_ITER_IS_EXTENTS) {
2541 bch2_key_resize(&iter->k,
2542 min_t(u64, KEY_SIZE_MAX,
2543 (next.inode == iter->pos.inode
2547 EBUG_ON(!iter->k.size);
2550 k = (struct bkey_s_c) { &iter->k, NULL };
2554 btree_path_set_should_be_locked(iter->path);
2556 bch2_btree_iter_verify_entry_exit(iter);
2557 bch2_btree_iter_verify(iter);
2558 ret = bch2_btree_iter_verify_ret(iter, k);
2560 return bkey_s_c_err(ret);
2565 struct bkey_s_c bch2_btree_iter_next_slot(struct btree_iter *iter)
2567 if (!bch2_btree_iter_advance(iter))
2568 return bkey_s_c_null;
2570 return bch2_btree_iter_peek_slot(iter);
2573 struct bkey_s_c bch2_btree_iter_prev_slot(struct btree_iter *iter)
2575 if (!bch2_btree_iter_rewind(iter))
2576 return bkey_s_c_null;
2578 return bch2_btree_iter_peek_slot(iter);
2581 struct bkey_s_c bch2_btree_iter_peek_and_restart_outlined(struct btree_iter *iter)
2585 while (btree_trans_too_many_iters(iter->trans) ||
2586 (k = bch2_btree_iter_peek_type(iter, iter->flags),
2587 bch2_err_matches(bkey_err(k), BCH_ERR_transaction_restart)))
2588 bch2_trans_begin(iter->trans);
2593 /* new transactional stuff: */
2595 #ifdef CONFIG_BCACHEFS_DEBUG
2596 static void btree_trans_verify_sorted_refs(struct btree_trans *trans)
2598 struct btree_path *path;
2601 BUG_ON(trans->nr_sorted != hweight64(trans->paths_allocated));
2603 trans_for_each_path(trans, path) {
2604 BUG_ON(path->sorted_idx >= trans->nr_sorted);
2605 BUG_ON(trans->sorted[path->sorted_idx] != path->idx);
2608 for (i = 0; i < trans->nr_sorted; i++) {
2609 unsigned idx = trans->sorted[i];
2611 EBUG_ON(!(trans->paths_allocated & (1ULL << idx)));
2612 BUG_ON(trans->paths[idx].sorted_idx != i);
2616 static void btree_trans_verify_sorted(struct btree_trans *trans)
2618 struct btree_path *path, *prev = NULL;
2621 if (!bch2_debug_check_iterators)
2624 trans_for_each_path_inorder(trans, path, i) {
2625 if (prev && btree_path_cmp(prev, path) > 0) {
2626 __bch2_dump_trans_paths_updates(trans, true);
2627 panic("trans paths out of order!\n");
2633 static inline void btree_trans_verify_sorted_refs(struct btree_trans *trans) {}
2634 static inline void btree_trans_verify_sorted(struct btree_trans *trans) {}
2637 void __bch2_btree_trans_sort_paths(struct btree_trans *trans)
2639 int i, l = 0, r = trans->nr_sorted, inc = 1;
2642 btree_trans_verify_sorted_refs(trans);
2644 if (trans->paths_sorted)
2648 * Cocktail shaker sort: this is efficient because iterators will be
2654 for (i = inc > 0 ? l : r - 2;
2655 i + 1 < r && i >= l;
2657 if (btree_path_cmp(trans->paths + trans->sorted[i],
2658 trans->paths + trans->sorted[i + 1]) > 0) {
2659 swap(trans->sorted[i], trans->sorted[i + 1]);
2660 trans->paths[trans->sorted[i]].sorted_idx = i;
2661 trans->paths[trans->sorted[i + 1]].sorted_idx = i + 1;
2673 trans->paths_sorted = true;
2675 btree_trans_verify_sorted(trans);
2678 static inline void btree_path_list_remove(struct btree_trans *trans,
2679 struct btree_path *path)
2683 EBUG_ON(path->sorted_idx >= trans->nr_sorted);
2684 #ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
2686 memmove_u64s_down_small(trans->sorted + path->sorted_idx,
2687 trans->sorted + path->sorted_idx + 1,
2688 DIV_ROUND_UP(trans->nr_sorted - path->sorted_idx, 8));
2690 array_remove_item(trans->sorted, trans->nr_sorted, path->sorted_idx);
2692 for (i = path->sorted_idx; i < trans->nr_sorted; i++)
2693 trans->paths[trans->sorted[i]].sorted_idx = i;
2695 path->sorted_idx = U8_MAX;
2698 static inline void btree_path_list_add(struct btree_trans *trans,
2699 struct btree_path *pos,
2700 struct btree_path *path)
2704 path->sorted_idx = pos ? pos->sorted_idx + 1 : trans->nr_sorted;
2706 #ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
2707 memmove_u64s_up_small(trans->sorted + path->sorted_idx + 1,
2708 trans->sorted + path->sorted_idx,
2709 DIV_ROUND_UP(trans->nr_sorted - path->sorted_idx, 8));
2711 trans->sorted[path->sorted_idx] = path->idx;
2713 array_insert_item(trans->sorted, trans->nr_sorted, path->sorted_idx, path->idx);
2716 for (i = path->sorted_idx; i < trans->nr_sorted; i++)
2717 trans->paths[trans->sorted[i]].sorted_idx = i;
2719 btree_trans_verify_sorted_refs(trans);
2722 void bch2_trans_iter_exit(struct btree_trans *trans, struct btree_iter *iter)
2724 if (iter->update_path)
2725 bch2_path_put_nokeep(trans, iter->update_path,
2726 iter->flags & BTREE_ITER_INTENT);
2728 bch2_path_put(trans, iter->path,
2729 iter->flags & BTREE_ITER_INTENT);
2730 if (iter->key_cache_path)
2731 bch2_path_put(trans, iter->key_cache_path,
2732 iter->flags & BTREE_ITER_INTENT);
2734 iter->update_path = NULL;
2735 iter->key_cache_path = NULL;
2738 static inline void bch2_trans_iter_init_inlined(struct btree_trans *trans,
2739 struct btree_iter *iter,
2740 unsigned btree_id, struct bpos pos,
2743 bch2_trans_iter_init_common(trans, iter, btree_id, pos, 0, 0,
2744 bch2_btree_iter_flags(trans, btree_id, flags),
2748 void bch2_trans_iter_init_outlined(struct btree_trans *trans,
2749 struct btree_iter *iter,
2750 unsigned btree_id, struct bpos pos,
2753 bch2_trans_iter_init_common(trans, iter, btree_id, pos, 0, 0,
2754 bch2_btree_iter_flags(trans, btree_id, flags),
2758 void bch2_trans_node_iter_init(struct btree_trans *trans,
2759 struct btree_iter *iter,
2760 enum btree_id btree_id,
2762 unsigned locks_want,
2766 flags |= BTREE_ITER_NOT_EXTENTS;
2767 flags |= __BTREE_ITER_ALL_SNAPSHOTS;
2768 flags |= BTREE_ITER_ALL_SNAPSHOTS;
2770 bch2_trans_iter_init_common(trans, iter, btree_id, pos, locks_want, depth,
2771 __bch2_btree_iter_flags(trans, btree_id, flags),
2774 iter->min_depth = depth;
2776 BUG_ON(iter->path->locks_want < min(locks_want, BTREE_MAX_DEPTH));
2777 BUG_ON(iter->path->level != depth);
2778 BUG_ON(iter->min_depth != depth);
2781 void bch2_trans_copy_iter(struct btree_iter *dst, struct btree_iter *src)
2785 __btree_path_get(src->path, src->flags & BTREE_ITER_INTENT);
2786 if (src->update_path)
2787 __btree_path_get(src->update_path, src->flags & BTREE_ITER_INTENT);
2788 dst->key_cache_path = NULL;
2791 void *__bch2_trans_kmalloc(struct btree_trans *trans, size_t size)
2793 unsigned new_top = trans->mem_top + size;
2794 size_t old_bytes = trans->mem_bytes;
2795 size_t new_bytes = roundup_pow_of_two(new_top);
2799 trans->mem_max = max(trans->mem_max, new_top);
2801 WARN_ON_ONCE(new_bytes > BTREE_TRANS_MEM_MAX);
2803 new_mem = krealloc(trans->mem, new_bytes, GFP_NOFS);
2804 if (!new_mem && new_bytes <= BTREE_TRANS_MEM_MAX) {
2805 new_mem = mempool_alloc(&trans->c->btree_trans_mem_pool, GFP_KERNEL);
2806 new_bytes = BTREE_TRANS_MEM_MAX;
2811 return ERR_PTR(-BCH_ERR_ENOMEM_trans_kmalloc);
2813 trans->mem = new_mem;
2814 trans->mem_bytes = new_bytes;
2817 trace_and_count(trans->c, trans_restart_mem_realloced, trans, _RET_IP_, new_bytes);
2818 return ERR_PTR(btree_trans_restart(trans, BCH_ERR_transaction_restart_mem_realloced));
2821 p = trans->mem + trans->mem_top;
2822 trans->mem_top += size;
2827 static noinline void bch2_trans_reset_srcu_lock(struct btree_trans *trans)
2829 struct bch_fs *c = trans->c;
2830 struct btree_path *path;
2832 trans_for_each_path(trans, path)
2833 if (path->cached && !btree_node_locked(path, 0))
2834 path->l[0].b = ERR_PTR(-BCH_ERR_no_btree_node_srcu_reset);
2836 srcu_read_unlock(&c->btree_trans_barrier, trans->srcu_idx);
2837 trans->srcu_idx = srcu_read_lock(&c->btree_trans_barrier);
2838 trans->srcu_lock_time = jiffies;
2842 * bch2_trans_begin() - reset a transaction after a interrupted attempt
2843 * @trans: transaction to reset
2845 * While iterating over nodes or updating nodes a attempt to lock a btree node
2846 * may return BCH_ERR_transaction_restart when the trylock fails. When this
2847 * occurs bch2_trans_begin() should be called and the transaction retried.
2849 u32 bch2_trans_begin(struct btree_trans *trans)
2851 struct btree_path *path;
2853 bch2_trans_reset_updates(trans);
2855 trans->restart_count++;
2858 trans_for_each_path(trans, path) {
2859 path->should_be_locked = false;
2862 * If the transaction wasn't restarted, we're presuming to be
2863 * doing something new: dont keep iterators excpt the ones that
2864 * are in use - except for the subvolumes btree:
2866 if (!trans->restarted && path->btree_id != BTREE_ID_subvolumes)
2867 path->preserve = false;
2870 * XXX: we probably shouldn't be doing this if the transaction
2871 * was restarted, but currently we still overflow transaction
2872 * iterators if we do that
2874 if (!path->ref && !path->preserve)
2875 __bch2_path_free(trans, path);
2877 path->preserve = false;
2880 if (!trans->restarted &&
2882 local_clock() - trans->last_begin_time > BTREE_TRANS_MAX_LOCK_HOLD_TIME_NS)) {
2883 bch2_trans_unlock(trans);
2885 bch2_trans_relock(trans);
2888 if (unlikely(time_after(jiffies, trans->srcu_lock_time + msecs_to_jiffies(10))))
2889 bch2_trans_reset_srcu_lock(trans);
2891 trans->last_begin_ip = _RET_IP_;
2892 if (trans->restarted) {
2893 bch2_btree_path_traverse_all(trans);
2894 trans->notrace_relock_fail = false;
2897 trans->last_begin_time = local_clock();
2898 return trans->restart_count;
2901 static void bch2_trans_alloc_paths(struct btree_trans *trans, struct bch_fs *c)
2903 size_t paths_bytes = sizeof(struct btree_path) * BTREE_ITER_MAX;
2904 size_t updates_bytes = sizeof(struct btree_insert_entry) * BTREE_ITER_MAX;
2907 BUG_ON(trans->used_mempool);
2910 p = this_cpu_xchg(c->btree_paths_bufs->path, NULL);
2913 p = mempool_alloc(&trans->c->btree_paths_pool, GFP_NOFS);
2915 trans->paths = p; p += paths_bytes;
2916 trans->updates = p; p += updates_bytes;
2919 const char *bch2_btree_transaction_fns[BCH_TRANSACTIONS_NR];
2921 unsigned bch2_trans_get_fn_idx(const char *fn)
2925 for (i = 0; i < ARRAY_SIZE(bch2_btree_transaction_fns); i++)
2926 if (!bch2_btree_transaction_fns[i] ||
2927 bch2_btree_transaction_fns[i] == fn) {
2928 bch2_btree_transaction_fns[i] = fn;
2932 pr_warn_once("BCH_TRANSACTIONS_NR not big enough!");
2936 void __bch2_trans_init(struct btree_trans *trans, struct bch_fs *c, unsigned fn_idx)
2937 __acquires(&c->btree_trans_barrier)
2939 struct btree_transaction_stats *s;
2941 bch2_assert_btree_nodes_not_locked();
2943 memset(trans, 0, sizeof(*trans));
2945 trans->fn = fn_idx < ARRAY_SIZE(bch2_btree_transaction_fns)
2946 ? bch2_btree_transaction_fns[fn_idx] : NULL;
2947 trans->last_begin_time = local_clock();
2948 trans->fn_idx = fn_idx;
2949 trans->locking_wait.task = current;
2950 trans->journal_replay_not_finished =
2951 !test_bit(JOURNAL_REPLAY_DONE, &c->journal.flags);
2952 closure_init_stack(&trans->ref);
2954 bch2_trans_alloc_paths(trans, c);
2956 s = btree_trans_stats(trans);
2957 if (s && s->max_mem) {
2958 unsigned expected_mem_bytes = roundup_pow_of_two(s->max_mem);
2960 trans->mem = kmalloc(expected_mem_bytes, GFP_KERNEL);
2962 if (!unlikely(trans->mem)) {
2963 trans->mem = mempool_alloc(&c->btree_trans_mem_pool, GFP_KERNEL);
2964 trans->mem_bytes = BTREE_TRANS_MEM_MAX;
2966 trans->mem_bytes = expected_mem_bytes;
2971 trans->nr_max_paths = s->nr_max_paths;
2972 trans->wb_updates_size = s->wb_updates_size;
2975 trans->srcu_idx = srcu_read_lock(&c->btree_trans_barrier);
2976 trans->srcu_lock_time = jiffies;
2978 if (IS_ENABLED(CONFIG_BCACHEFS_DEBUG_TRANSACTIONS)) {
2979 struct btree_trans *pos;
2981 mutex_lock(&c->btree_trans_lock);
2982 list_for_each_entry(pos, &c->btree_trans_list, list) {
2984 * We'd much prefer to be stricter here and completely
2985 * disallow multiple btree_trans in the same thread -
2986 * but the data move path calls bch2_write when we
2987 * already have a btree_trans initialized.
2989 BUG_ON(trans->locking_wait.task->pid == pos->locking_wait.task->pid &&
2990 bch2_trans_locked(pos));
2992 if (trans->locking_wait.task->pid < pos->locking_wait.task->pid) {
2993 list_add_tail(&trans->list, &pos->list);
2997 list_add_tail(&trans->list, &c->btree_trans_list);
2999 mutex_unlock(&c->btree_trans_lock);
3003 static void check_btree_paths_leaked(struct btree_trans *trans)
3005 #ifdef CONFIG_BCACHEFS_DEBUG
3006 struct bch_fs *c = trans->c;
3007 struct btree_path *path;
3009 trans_for_each_path(trans, path)
3014 bch_err(c, "btree paths leaked from %s!", trans->fn);
3015 trans_for_each_path(trans, path)
3017 printk(KERN_ERR " btree %s %pS\n",
3018 bch2_btree_ids[path->btree_id],
3019 (void *) path->ip_allocated);
3020 /* Be noisy about this: */
3021 bch2_fatal_error(c);
3025 void bch2_trans_exit(struct btree_trans *trans)
3026 __releases(&c->btree_trans_barrier)
3028 struct btree_insert_entry *i;
3029 struct bch_fs *c = trans->c;
3030 struct btree_transaction_stats *s = btree_trans_stats(trans);
3032 bch2_trans_unlock(trans);
3034 closure_sync(&trans->ref);
3037 s->max_mem = max(s->max_mem, trans->mem_max);
3039 trans_for_each_update(trans, i)
3040 __btree_path_put(i->path, true);
3041 trans->nr_updates = 0;
3043 check_btree_paths_leaked(trans);
3045 if (IS_ENABLED(CONFIG_BCACHEFS_DEBUG_TRANSACTIONS)) {
3046 mutex_lock(&c->btree_trans_lock);
3047 list_del(&trans->list);
3048 mutex_unlock(&c->btree_trans_lock);
3051 srcu_read_unlock(&c->btree_trans_barrier, trans->srcu_idx);
3053 bch2_journal_preres_put(&c->journal, &trans->journal_preres);
3055 kfree(trans->extra_journal_entries.data);
3057 if (trans->fs_usage_deltas) {
3058 if (trans->fs_usage_deltas->size + sizeof(trans->fs_usage_deltas) ==
3059 REPLICAS_DELTA_LIST_MAX)
3060 mempool_free(trans->fs_usage_deltas,
3061 &c->replicas_delta_pool);
3063 kfree(trans->fs_usage_deltas);
3066 if (trans->mem_bytes == BTREE_TRANS_MEM_MAX)
3067 mempool_free(trans->mem, &c->btree_trans_mem_pool);
3073 * Userspace doesn't have a real percpu implementation:
3075 trans->paths = this_cpu_xchg(c->btree_paths_bufs->path, trans->paths);
3079 mempool_free(trans->paths, &c->btree_paths_pool);
3081 trans->mem = (void *) 0x1;
3082 trans->paths = (void *) 0x1;
3085 static void __maybe_unused
3086 bch2_btree_bkey_cached_common_to_text(struct printbuf *out,
3087 struct btree_bkey_cached_common *b)
3089 struct six_lock_count c = six_lock_counts(&b->lock);
3090 struct task_struct *owner;
3094 owner = READ_ONCE(b->lock.owner);
3095 pid = owner ? owner->pid : 0;
3099 prt_printf(out, "%px %c l=%u %s:", b, b->cached ? 'c' : 'b',
3100 b->level, bch2_btree_ids[b->btree_id]);
3101 bch2_bpos_to_text(out, btree_node_pos(b));
3104 prt_printf(out, " locks %u:%u:%u held by pid %u",
3105 c.n[0], c.n[1], c.n[2], pid);
3108 void bch2_btree_trans_to_text(struct printbuf *out, struct btree_trans *trans)
3110 struct btree_path *path;
3111 struct btree_bkey_cached_common *b;
3112 static char lock_types[] = { 'r', 'i', 'w' };
3115 if (!out->nr_tabstops) {
3116 printbuf_tabstop_push(out, 16);
3117 printbuf_tabstop_push(out, 32);
3120 prt_printf(out, "%i %s\n", trans->locking_wait.task->pid, trans->fn);
3122 trans_for_each_path(trans, path) {
3123 if (!path->nodes_locked)
3126 prt_printf(out, " path %u %c l=%u %s:",
3128 path->cached ? 'c' : 'b',
3130 bch2_btree_ids[path->btree_id]);
3131 bch2_bpos_to_text(out, path->pos);
3134 for (l = 0; l < BTREE_MAX_DEPTH; l++) {
3135 if (btree_node_locked(path, l) &&
3136 !IS_ERR_OR_NULL(b = (void *) READ_ONCE(path->l[l].b))) {
3137 prt_printf(out, " %c l=%u ",
3138 lock_types[btree_node_locked_type(path, l)], l);
3139 bch2_btree_bkey_cached_common_to_text(out, b);
3145 b = READ_ONCE(trans->locking);
3147 prt_printf(out, " blocked for %lluus on",
3148 div_u64(local_clock() - trans->locking_wait.start_time,
3151 prt_printf(out, " %c", lock_types[trans->locking_wait.lock_want]);
3152 bch2_btree_bkey_cached_common_to_text(out, b);
3157 void bch2_fs_btree_iter_exit(struct bch_fs *c)
3159 struct btree_transaction_stats *s;
3161 for (s = c->btree_transaction_stats;
3162 s < c->btree_transaction_stats + ARRAY_SIZE(c->btree_transaction_stats);
3164 kfree(s->max_paths_text);
3165 bch2_time_stats_exit(&s->lock_hold_times);
3168 if (c->btree_trans_barrier_initialized)
3169 cleanup_srcu_struct(&c->btree_trans_barrier);
3170 mempool_exit(&c->btree_trans_mem_pool);
3171 mempool_exit(&c->btree_paths_pool);
3174 int bch2_fs_btree_iter_init(struct bch_fs *c)
3176 struct btree_transaction_stats *s;
3177 unsigned nr = BTREE_ITER_MAX;
3180 for (s = c->btree_transaction_stats;
3181 s < c->btree_transaction_stats + ARRAY_SIZE(c->btree_transaction_stats);
3183 bch2_time_stats_init(&s->lock_hold_times);
3184 mutex_init(&s->lock);
3187 INIT_LIST_HEAD(&c->btree_trans_list);
3188 mutex_init(&c->btree_trans_lock);
3190 ret = mempool_init_kmalloc_pool(&c->btree_paths_pool, 1,
3191 sizeof(struct btree_path) * nr +
3192 sizeof(struct btree_insert_entry) * nr) ?:
3193 mempool_init_kmalloc_pool(&c->btree_trans_mem_pool, 1,
3194 BTREE_TRANS_MEM_MAX) ?:
3195 init_srcu_struct(&c->btree_trans_barrier);
3197 c->btree_trans_barrier_initialized = true;