1 // SPDX-License-Identifier: GPL-2.0
3 * Copyright (C) 2010 Kent Overstreet <kent.overstreet@gmail.com>
4 * Copyright (C) 2014 Datera Inc.
8 #include "alloc_background.h"
9 #include "alloc_foreground.h"
10 #include "bkey_methods.h"
12 #include "btree_key_cache.h"
13 #include "btree_locking.h"
14 #include "btree_update_interior.h"
31 #include <linux/slab.h>
32 #include <linux/bitops.h>
33 #include <linux/freezer.h>
34 #include <linux/kthread.h>
35 #include <linux/preempt.h>
36 #include <linux/rcupdate.h>
37 #include <linux/sched/task.h>
38 #include <trace/events/bcachefs.h>
40 #define DROP_THIS_NODE 10
41 #define DROP_PREV_NODE 11
43 static inline void __gc_pos_set(struct bch_fs *c, struct gc_pos new_pos)
46 write_seqcount_begin(&c->gc_pos_lock);
48 write_seqcount_end(&c->gc_pos_lock);
52 static inline void gc_pos_set(struct bch_fs *c, struct gc_pos new_pos)
54 BUG_ON(gc_pos_cmp(new_pos, c->gc_pos) <= 0);
55 __gc_pos_set(c, new_pos);
59 * Missing: if an interior btree node is empty, we need to do something -
60 * perhaps just kill it
62 static int bch2_gc_check_topology(struct bch_fs *c,
64 struct bkey_buf *prev,
68 struct bpos node_start = b->data->min_key;
69 struct bpos node_end = b->data->max_key;
70 struct bpos expected_start = bkey_deleted(&prev->k->k)
72 : bpos_successor(prev->k->k.p);
73 char buf1[200], buf2[200];
76 if (cur.k->k.type == KEY_TYPE_btree_ptr_v2) {
77 struct bkey_i_btree_ptr_v2 *bp = bkey_i_to_btree_ptr_v2(cur.k);
79 if (bkey_deleted(&prev->k->k)) {
80 struct printbuf out = PBUF(buf1);
81 pr_buf(&out, "start of node: ");
82 bch2_bpos_to_text(&out, node_start);
84 bch2_bkey_val_to_text(&PBUF(buf1), c, bkey_i_to_s_c(prev->k));
87 if (bpos_cmp(expected_start, bp->v.min_key)) {
88 bch2_topology_error(c);
94 "btree node with incorrect min_key at btree %s level %u:\n"
97 bch2_btree_ids[b->c.btree_id], b->c.level,
99 (bch2_bkey_val_to_text(&PBUF(buf2), c, bkey_i_to_s_c(cur.k)), buf2)) &&
100 !test_bit(BCH_FS_TOPOLOGY_REPAIR_DONE, &c->flags)) {
101 bch_info(c, "Halting mark and sweep to start topology repair pass");
102 return FSCK_ERR_START_TOPOLOGY_REPAIR;
104 set_bit(BCH_FS_INITIAL_GC_UNFIXED, &c->flags);
109 if (is_last && bpos_cmp(cur.k->k.p, node_end)) {
110 bch2_topology_error(c);
116 "btree node with incorrect max_key at btree %s level %u:\n"
119 bch2_btree_ids[b->c.btree_id], b->c.level,
120 (bch2_bkey_val_to_text(&PBUF(buf1), c, bkey_i_to_s_c(cur.k)), buf1),
121 (bch2_bpos_to_text(&PBUF(buf2), node_end), buf2)) &&
122 !test_bit(BCH_FS_TOPOLOGY_REPAIR_DONE, &c->flags)) {
123 bch_info(c, "Halting mark and sweep to start topology repair pass");
124 return FSCK_ERR_START_TOPOLOGY_REPAIR;
126 set_bit(BCH_FS_INITIAL_GC_UNFIXED, &c->flags);
130 bch2_bkey_buf_copy(prev, c, cur.k);
135 static void btree_ptr_to_v2(struct btree *b, struct bkey_i_btree_ptr_v2 *dst)
137 switch (b->key.k.type) {
138 case KEY_TYPE_btree_ptr: {
139 struct bkey_i_btree_ptr *src = bkey_i_to_btree_ptr(&b->key);
143 dst->v.seq = b->data->keys.seq;
144 dst->v.sectors_written = 0;
146 dst->v.min_key = b->data->min_key;
147 set_bkey_val_bytes(&dst->k, sizeof(dst->v) + bkey_val_bytes(&src->k));
148 memcpy(dst->v.start, src->v.start, bkey_val_bytes(&src->k));
151 case KEY_TYPE_btree_ptr_v2:
152 bkey_copy(&dst->k_i, &b->key);
159 static int set_node_min(struct bch_fs *c, struct btree *b, struct bpos new_min)
161 struct bkey_i_btree_ptr_v2 *new;
164 new = kmalloc(BKEY_BTREE_PTR_U64s_MAX * sizeof(u64), GFP_KERNEL);
168 btree_ptr_to_v2(b, new);
169 b->data->min_key = new_min;
170 new->v.min_key = new_min;
171 SET_BTREE_PTR_RANGE_UPDATED(&new->v, true);
173 ret = bch2_journal_key_insert_take(c, b->c.btree_id, b->c.level + 1, &new->k_i);
179 bch2_btree_node_drop_keys_outside_node(b);
184 static int set_node_max(struct bch_fs *c, struct btree *b, struct bpos new_max)
186 struct bkey_i_btree_ptr_v2 *new;
189 ret = bch2_journal_key_delete(c, b->c.btree_id, b->c.level + 1, b->key.k.p);
193 new = kmalloc(BKEY_BTREE_PTR_U64s_MAX * sizeof(u64), GFP_KERNEL);
197 btree_ptr_to_v2(b, new);
198 b->data->max_key = new_max;
200 SET_BTREE_PTR_RANGE_UPDATED(&new->v, true);
202 ret = bch2_journal_key_insert_take(c, b->c.btree_id, b->c.level + 1, &new->k_i);
208 bch2_btree_node_drop_keys_outside_node(b);
210 mutex_lock(&c->btree_cache.lock);
211 bch2_btree_node_hash_remove(&c->btree_cache, b);
213 bkey_copy(&b->key, &new->k_i);
214 ret = __bch2_btree_node_hash_insert(&c->btree_cache, b);
216 mutex_unlock(&c->btree_cache.lock);
220 static int btree_repair_node_boundaries(struct bch_fs *c, struct btree *b,
221 struct btree *prev, struct btree *cur)
223 struct bpos expected_start = !prev
225 : bpos_successor(prev->key.k.p);
226 char buf1[200], buf2[200];
230 struct printbuf out = PBUF(buf1);
231 pr_buf(&out, "start of node: ");
232 bch2_bpos_to_text(&out, b->data->min_key);
234 bch2_bkey_val_to_text(&PBUF(buf1), c, bkey_i_to_s_c(&prev->key));
237 bch2_bkey_val_to_text(&PBUF(buf2), c, bkey_i_to_s_c(&cur->key));
240 bpos_cmp(expected_start, cur->data->min_key) > 0 &&
241 BTREE_NODE_SEQ(cur->data) > BTREE_NODE_SEQ(prev->data)) {
242 /* cur overwrites prev: */
244 if (mustfix_fsck_err_on(bpos_cmp(prev->data->min_key,
245 cur->data->min_key) >= 0, c,
246 "btree node overwritten by next node at btree %s level %u:\n"
249 bch2_btree_ids[b->c.btree_id], b->c.level,
251 return DROP_PREV_NODE;
253 if (mustfix_fsck_err_on(bpos_cmp(prev->key.k.p,
254 bpos_predecessor(cur->data->min_key)), c,
255 "btree node with incorrect max_key at btree %s level %u:\n"
258 bch2_btree_ids[b->c.btree_id], b->c.level,
260 ret = set_node_max(c, prev,
261 bpos_predecessor(cur->data->min_key));
263 /* prev overwrites cur: */
265 if (mustfix_fsck_err_on(bpos_cmp(expected_start,
266 cur->data->max_key) >= 0, c,
267 "btree node overwritten by prev node at btree %s level %u:\n"
270 bch2_btree_ids[b->c.btree_id], b->c.level,
272 return DROP_THIS_NODE;
274 if (mustfix_fsck_err_on(bpos_cmp(expected_start, cur->data->min_key), c,
275 "btree node with incorrect min_key at btree %s level %u:\n"
278 bch2_btree_ids[b->c.btree_id], b->c.level,
280 ret = set_node_min(c, cur, expected_start);
286 static int btree_repair_node_end(struct bch_fs *c, struct btree *b,
289 char buf1[200], buf2[200];
292 if (mustfix_fsck_err_on(bpos_cmp(child->key.k.p, b->key.k.p), c,
293 "btree node with incorrect max_key at btree %s level %u:\n"
296 bch2_btree_ids[b->c.btree_id], b->c.level,
297 (bch2_bkey_val_to_text(&PBUF(buf1), c, bkey_i_to_s_c(&child->key)), buf1),
298 (bch2_bpos_to_text(&PBUF(buf2), b->key.k.p), buf2))) {
299 ret = set_node_max(c, child, b->key.k.p);
307 static int bch2_btree_repair_topology_recurse(struct bch_fs *c, struct btree *b)
309 struct btree_and_journal_iter iter;
311 struct bkey_buf prev_k, cur_k;
312 struct btree *prev = NULL, *cur = NULL;
313 bool have_child, dropped_children = false;
321 have_child = dropped_children = false;
322 bch2_bkey_buf_init(&prev_k);
323 bch2_bkey_buf_init(&cur_k);
324 bch2_btree_and_journal_iter_init_node_iter(&iter, c, b);
326 while ((k = bch2_btree_and_journal_iter_peek(&iter)).k) {
327 BUG_ON(bpos_cmp(k.k->p, b->data->min_key) < 0);
328 BUG_ON(bpos_cmp(k.k->p, b->data->max_key) > 0);
330 bch2_btree_and_journal_iter_advance(&iter);
331 bch2_bkey_buf_reassemble(&cur_k, c, k);
333 cur = bch2_btree_node_get_noiter(c, cur_k.k,
334 b->c.btree_id, b->c.level - 1,
336 ret = PTR_ERR_OR_ZERO(cur);
338 if (mustfix_fsck_err_on(ret == -EIO, c,
339 "Unreadable btree node at btree %s level %u:\n"
341 bch2_btree_ids[b->c.btree_id],
343 (bch2_bkey_val_to_text(&PBUF(buf), c, bkey_i_to_s_c(cur_k.k)), buf))) {
344 bch2_btree_node_evict(c, cur_k.k);
345 ret = bch2_journal_key_delete(c, b->c.btree_id,
346 b->c.level, cur_k.k->k.p);
353 bch_err(c, "%s: error %i getting btree node",
358 ret = btree_repair_node_boundaries(c, b, prev, cur);
360 if (ret == DROP_THIS_NODE) {
361 six_unlock_read(&cur->c.lock);
362 bch2_btree_node_evict(c, cur_k.k);
363 ret = bch2_journal_key_delete(c, b->c.btree_id,
364 b->c.level, cur_k.k->k.p);
371 six_unlock_read(&prev->c.lock);
374 if (ret == DROP_PREV_NODE) {
375 bch2_btree_node_evict(c, prev_k.k);
376 ret = bch2_journal_key_delete(c, b->c.btree_id,
377 b->c.level, prev_k.k->k.p);
381 bch2_btree_and_journal_iter_exit(&iter);
382 bch2_bkey_buf_exit(&prev_k, c);
383 bch2_bkey_buf_exit(&cur_k, c);
390 bch2_bkey_buf_copy(&prev_k, c, cur_k.k);
393 if (!ret && !IS_ERR_OR_NULL(prev)) {
395 ret = btree_repair_node_end(c, b, prev);
398 if (!IS_ERR_OR_NULL(prev))
399 six_unlock_read(&prev->c.lock);
401 if (!IS_ERR_OR_NULL(cur))
402 six_unlock_read(&cur->c.lock);
408 bch2_btree_and_journal_iter_exit(&iter);
409 bch2_btree_and_journal_iter_init_node_iter(&iter, c, b);
411 while ((k = bch2_btree_and_journal_iter_peek(&iter)).k) {
412 bch2_bkey_buf_reassemble(&cur_k, c, k);
413 bch2_btree_and_journal_iter_advance(&iter);
415 cur = bch2_btree_node_get_noiter(c, cur_k.k,
416 b->c.btree_id, b->c.level - 1,
418 ret = PTR_ERR_OR_ZERO(cur);
421 bch_err(c, "%s: error %i getting btree node",
426 ret = bch2_btree_repair_topology_recurse(c, cur);
427 six_unlock_read(&cur->c.lock);
430 if (ret == DROP_THIS_NODE) {
431 bch2_btree_node_evict(c, cur_k.k);
432 ret = bch2_journal_key_delete(c, b->c.btree_id,
433 b->c.level, cur_k.k->k.p);
434 dropped_children = true;
443 if (mustfix_fsck_err_on(!have_child, c,
444 "empty interior btree node at btree %s level %u\n"
446 bch2_btree_ids[b->c.btree_id],
448 (bch2_bkey_val_to_text(&PBUF(buf), c, bkey_i_to_s_c(&b->key)), buf)))
449 ret = DROP_THIS_NODE;
452 if (!IS_ERR_OR_NULL(prev))
453 six_unlock_read(&prev->c.lock);
454 if (!IS_ERR_OR_NULL(cur))
455 six_unlock_read(&cur->c.lock);
457 bch2_btree_and_journal_iter_exit(&iter);
458 bch2_bkey_buf_exit(&prev_k, c);
459 bch2_bkey_buf_exit(&cur_k, c);
461 if (!ret && dropped_children)
467 static int bch2_repair_topology(struct bch_fs *c)
473 for (i = 0; i < BTREE_ID_NR && !ret; i++) {
474 b = c->btree_roots[i].b;
475 if (btree_node_fake(b))
478 six_lock_read(&b->c.lock, NULL, NULL);
479 ret = bch2_btree_repair_topology_recurse(c, b);
480 six_unlock_read(&b->c.lock);
482 if (ret == DROP_THIS_NODE) {
483 bch_err(c, "empty btree root - repair unimplemented");
491 static int bch2_check_fix_ptrs(struct bch_fs *c, enum btree_id btree_id,
492 unsigned level, bool is_root,
495 struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(*k);
496 const union bch_extent_entry *entry;
497 struct extent_ptr_decoded p = { 0 };
498 bool do_update = false;
504 * use check_bucket_ref here
506 bkey_for_each_ptr_decode(k->k, ptrs, p, entry) {
507 struct bch_dev *ca = bch_dev_bkey_exists(c, p.ptr.dev);
508 struct bucket *g = PTR_GC_BUCKET(ca, &p.ptr);
509 enum bch_data_type data_type = bch2_bkey_ptr_data_type(*k, &entry->ptr);
511 if (fsck_err_on(!g->gen_valid, c,
512 "bucket %u:%zu data type %s ptr gen %u missing in alloc btree\n"
514 p.ptr.dev, PTR_BUCKET_NR(ca, &p.ptr),
515 bch2_data_types[ptr_data_type(k->k, &p.ptr)],
517 (bch2_bkey_val_to_text(&PBUF(buf), c, *k), buf))) {
519 g->_mark.gen = p.ptr.gen;
526 if (fsck_err_on(data_type == BCH_DATA_btree &&
527 g->mark.gen != p.ptr.gen, c,
528 "bucket %u:%zu data type %s has metadata but wrong gen: %u != %u\n"
530 p.ptr.dev, PTR_BUCKET_NR(ca, &p.ptr),
531 bch2_data_types[ptr_data_type(k->k, &p.ptr)],
532 p.ptr.gen, g->mark.gen,
533 (bch2_bkey_val_to_text(&PBUF(buf), c, *k), buf))) {
534 g->_mark.data_type = data_type;
538 if (fsck_err_on(gen_cmp(p.ptr.gen, g->mark.gen) > 0, c,
539 "bucket %u:%zu data type %s ptr gen in the future: %u > %u\n"
541 p.ptr.dev, PTR_BUCKET_NR(ca, &p.ptr),
542 bch2_data_types[ptr_data_type(k->k, &p.ptr)],
543 p.ptr.gen, g->mark.gen,
544 (bch2_bkey_val_to_text(&PBUF(buf), c, *k), buf))) {
546 g->_mark.gen = p.ptr.gen;
548 g->_mark.data_type = 0;
549 g->_mark.dirty_sectors = 0;
550 g->_mark.cached_sectors = 0;
551 set_bit(BCH_FS_NEED_ANOTHER_GC, &c->flags);
557 if (fsck_err_on(gen_cmp(g->mark.gen, p.ptr.gen) > BUCKET_GC_GEN_MAX, c,
558 "bucket %u:%zu gen %u data type %s: ptr gen %u too stale\n"
560 p.ptr.dev, PTR_BUCKET_NR(ca, &p.ptr), g->mark.gen,
561 bch2_data_types[ptr_data_type(k->k, &p.ptr)],
563 (bch2_bkey_val_to_text(&PBUF(buf), c, *k), buf)))
566 if (fsck_err_on(!p.ptr.cached &&
567 gen_cmp(p.ptr.gen, g->mark.gen) < 0, c,
568 "bucket %u:%zu data type %s stale dirty ptr: %u < %u\n"
570 p.ptr.dev, PTR_BUCKET_NR(ca, &p.ptr),
571 bch2_data_types[ptr_data_type(k->k, &p.ptr)],
572 p.ptr.gen, g->mark.gen,
573 (bch2_bkey_val_to_text(&PBUF(buf), c, *k), buf)))
576 if (p.ptr.gen != g->mark.gen)
579 if (fsck_err_on(g->mark.data_type &&
580 g->mark.data_type != data_type, c,
581 "bucket %u:%zu different types of data in same bucket: %s, %s\n"
583 p.ptr.dev, PTR_BUCKET_NR(ca, &p.ptr),
584 bch2_data_types[g->mark.data_type],
585 bch2_data_types[data_type],
586 (bch2_bkey_val_to_text(&PBUF(buf), c, *k), buf))) {
587 if (data_type == BCH_DATA_btree) {
588 g->_mark.data_type = data_type;
596 struct gc_stripe *m = genradix_ptr(&c->gc_stripes, p.ec.idx);
598 if (fsck_err_on(!m || !m->alive, c,
599 "pointer to nonexistent stripe %llu\n"
602 (bch2_bkey_val_to_text(&PBUF(buf), c, *k), buf)))
605 if (fsck_err_on(!bch2_ptr_matches_stripe_m(m, p), c,
606 "pointer does not match stripe %llu\n"
609 (bch2_bkey_val_to_text(&PBUF(buf), c, *k), buf)))
615 struct bkey_ptrs ptrs;
616 union bch_extent_entry *entry;
617 struct bch_extent_ptr *ptr;
621 bch_err(c, "cannot update btree roots yet");
625 new = kmalloc(bkey_bytes(k->k), GFP_KERNEL);
627 bch_err(c, "%s: error allocating new key", __func__);
631 bkey_reassemble(new, *k);
635 * We don't want to drop btree node pointers - if the
636 * btree node isn't there anymore, the read path will
639 ptrs = bch2_bkey_ptrs(bkey_i_to_s(new));
640 bkey_for_each_ptr(ptrs, ptr) {
641 struct bch_dev *ca = bch_dev_bkey_exists(c, ptr->dev);
642 struct bucket *g = PTR_GC_BUCKET(ca, ptr);
644 ptr->gen = g->mark.gen;
647 bch2_bkey_drop_ptrs(bkey_i_to_s(new), ptr, ({
648 struct bch_dev *ca = bch_dev_bkey_exists(c, ptr->dev);
649 struct bucket *g = PTR_GC_BUCKET(ca, ptr);
650 enum bch_data_type data_type = bch2_bkey_ptr_data_type(*k, ptr);
653 (!g->gen_valid || gen_cmp(ptr->gen, g->mark.gen) > 0)) ||
655 gen_cmp(ptr->gen, g->mark.gen) < 0) ||
656 gen_cmp(g->mark.gen, ptr->gen) > BUCKET_GC_GEN_MAX ||
657 (g->mark.data_type &&
658 g->mark.data_type != data_type);
661 ptrs = bch2_bkey_ptrs(bkey_i_to_s(new));
662 bkey_extent_entry_for_each(ptrs, entry) {
663 if (extent_entry_type(entry) == BCH_EXTENT_ENTRY_stripe_ptr) {
664 struct gc_stripe *m = genradix_ptr(&c->gc_stripes,
665 entry->stripe_ptr.idx);
666 union bch_extent_entry *next_ptr;
668 bkey_extent_entry_for_each_from(ptrs, next_ptr, entry)
669 if (extent_entry_type(next_ptr) == BCH_EXTENT_ENTRY_ptr)
674 bch_err(c, "aieee, found stripe ptr with no data ptr");
678 if (!m || !m->alive ||
679 !__bch2_ptr_matches_stripe(&m->ptrs[entry->stripe_ptr.block],
682 bch2_bkey_extent_entry_drop(new, entry);
689 ret = bch2_journal_key_insert_take(c, btree_id, level, new);
694 bch2_bkey_val_to_text(&PBUF(buf), c, *k);
695 bch_info(c, "updated %s", buf);
696 bch2_bkey_val_to_text(&PBUF(buf), c, bkey_i_to_s_c(new));
697 bch_info(c, "new key %s", buf);
698 *k = bkey_i_to_s_c(new);
705 /* marking of btree keys/nodes: */
707 static int bch2_gc_mark_key(struct btree_trans *trans, enum btree_id btree_id,
708 unsigned level, bool is_root,
710 u8 *max_stale, bool initial)
712 struct bch_fs *c = trans->c;
713 struct bkey_ptrs_c ptrs;
714 const struct bch_extent_ptr *ptr;
715 struct bkey deleted = KEY(0, 0, 0);
716 struct bkey_s_c old = (struct bkey_s_c) { &deleted, NULL };
719 (initial ? BTREE_TRIGGER_NOATOMIC : 0);
725 BUG_ON(bch2_journal_seq_verify &&
726 k->k->version.lo > journal_cur_seq(&c->journal));
728 ret = bch2_check_fix_ptrs(c, btree_id, level, is_root, k);
732 if (fsck_err_on(k->k->version.lo > atomic64_read(&c->key_version), c,
733 "key version number higher than recorded: %llu > %llu",
735 atomic64_read(&c->key_version)))
736 atomic64_set(&c->key_version, k->k->version.lo);
739 ptrs = bch2_bkey_ptrs_c(*k);
740 bkey_for_each_ptr(ptrs, ptr) {
741 struct bch_dev *ca = bch_dev_bkey_exists(c, ptr->dev);
742 struct bucket *g = PTR_GC_BUCKET(ca, ptr);
744 if (gen_after(g->oldest_gen, ptr->gen))
745 g->oldest_gen = ptr->gen;
747 *max_stale = max(*max_stale, ptr_stale(ca, ptr));
750 ret = bch2_mark_key(trans, old, *k, flags);
754 bch_err(c, "%s: ret %i", __func__, ret);
758 static int btree_gc_mark_node(struct btree_trans *trans, struct btree *b, u8 *max_stale,
761 struct bch_fs *c = trans->c;
762 struct btree_node_iter iter;
763 struct bkey unpacked;
765 struct bkey_buf prev, cur;
770 if (!btree_node_type_needs_gc(btree_node_type(b)))
773 bch2_btree_node_iter_init_from_start(&iter, b);
774 bch2_bkey_buf_init(&prev);
775 bch2_bkey_buf_init(&cur);
776 bkey_init(&prev.k->k);
778 while ((k = bch2_btree_node_iter_peek_unpack(&iter, b, &unpacked)).k) {
779 ret = bch2_gc_mark_key(trans, b->c.btree_id, b->c.level, false,
780 &k, max_stale, initial);
784 bch2_btree_node_iter_advance(&iter, b);
787 bch2_bkey_buf_reassemble(&cur, c, k);
789 ret = bch2_gc_check_topology(c, b, &prev, cur,
790 bch2_btree_node_iter_end(&iter));
796 bch2_bkey_buf_exit(&cur, c);
797 bch2_bkey_buf_exit(&prev, c);
801 static int bch2_gc_btree(struct btree_trans *trans, enum btree_id btree_id,
802 bool initial, bool metadata_only)
804 struct bch_fs *c = trans->c;
805 struct btree_iter iter;
807 unsigned depth = metadata_only ? 1
808 : bch2_expensive_debug_checks ? 0
809 : !btree_node_type_needs_gc(btree_id) ? 1
814 gc_pos_set(c, gc_pos_btree(btree_id, POS_MIN, 0));
816 __for_each_btree_node(trans, iter, btree_id, POS_MIN,
817 0, depth, BTREE_ITER_PREFETCH, b, ret) {
818 bch2_verify_btree_nr_keys(b);
820 gc_pos_set(c, gc_pos_btree_node(b));
822 ret = btree_gc_mark_node(trans, b, &max_stale, initial);
828 bch2_btree_node_rewrite(trans, &iter, b,
830 BTREE_INSERT_GC_LOCK_HELD);
831 else if (!bch2_btree_gc_rewrite_disabled &&
832 (bch2_btree_gc_always_rewrite || max_stale > 16))
833 bch2_btree_node_rewrite(trans, &iter,
834 b, BTREE_INSERT_NOWAIT|
835 BTREE_INSERT_GC_LOCK_HELD);
838 bch2_trans_iter_exit(trans, &iter);
843 mutex_lock(&c->btree_root_lock);
844 b = c->btree_roots[btree_id].b;
845 if (!btree_node_fake(b)) {
846 struct bkey_s_c k = bkey_i_to_s_c(&b->key);
848 ret = bch2_gc_mark_key(trans, b->c.btree_id, b->c.level, true,
849 &k, &max_stale, initial);
851 gc_pos_set(c, gc_pos_btree_root(b->c.btree_id));
852 mutex_unlock(&c->btree_root_lock);
857 static int bch2_gc_btree_init_recurse(struct btree_trans *trans, struct btree *b,
858 unsigned target_depth)
860 struct bch_fs *c = trans->c;
861 struct btree_and_journal_iter iter;
863 struct bkey_buf cur, prev;
868 bch2_btree_and_journal_iter_init_node_iter(&iter, c, b);
869 bch2_bkey_buf_init(&prev);
870 bch2_bkey_buf_init(&cur);
871 bkey_init(&prev.k->k);
873 while ((k = bch2_btree_and_journal_iter_peek(&iter)).k) {
874 BUG_ON(bpos_cmp(k.k->p, b->data->min_key) < 0);
875 BUG_ON(bpos_cmp(k.k->p, b->data->max_key) > 0);
877 ret = bch2_gc_mark_key(trans, b->c.btree_id, b->c.level, false,
878 &k, &max_stale, true);
880 bch_err(c, "%s: error %i from bch2_gc_mark_key", __func__, ret);
885 bch2_bkey_buf_reassemble(&cur, c, k);
886 k = bkey_i_to_s_c(cur.k);
888 bch2_btree_and_journal_iter_advance(&iter);
890 ret = bch2_gc_check_topology(c, b,
892 !bch2_btree_and_journal_iter_peek(&iter).k);
896 bch2_btree_and_journal_iter_advance(&iter);
900 if (b->c.level > target_depth) {
901 bch2_btree_and_journal_iter_exit(&iter);
902 bch2_btree_and_journal_iter_init_node_iter(&iter, c, b);
904 while ((k = bch2_btree_and_journal_iter_peek(&iter)).k) {
907 bch2_bkey_buf_reassemble(&cur, c, k);
908 bch2_btree_and_journal_iter_advance(&iter);
910 child = bch2_btree_node_get_noiter(c, cur.k,
911 b->c.btree_id, b->c.level - 1,
913 ret = PTR_ERR_OR_ZERO(child);
916 bch2_topology_error(c);
922 "Unreadable btree node at btree %s level %u:\n"
924 bch2_btree_ids[b->c.btree_id],
926 (bch2_bkey_val_to_text(&PBUF(buf), c, bkey_i_to_s_c(cur.k)), buf)) &&
927 !test_bit(BCH_FS_TOPOLOGY_REPAIR_DONE, &c->flags)) {
928 ret = FSCK_ERR_START_TOPOLOGY_REPAIR;
929 bch_info(c, "Halting mark and sweep to start topology repair pass");
932 /* Continue marking when opted to not
935 set_bit(BCH_FS_INITIAL_GC_UNFIXED, &c->flags);
939 bch_err(c, "%s: error %i getting btree node",
944 ret = bch2_gc_btree_init_recurse(trans, child,
946 six_unlock_read(&child->c.lock);
953 bch2_bkey_buf_exit(&cur, c);
954 bch2_bkey_buf_exit(&prev, c);
955 bch2_btree_and_journal_iter_exit(&iter);
959 static int bch2_gc_btree_init(struct btree_trans *trans,
960 enum btree_id btree_id,
963 struct bch_fs *c = trans->c;
965 unsigned target_depth = metadata_only ? 1
966 : bch2_expensive_debug_checks ? 0
967 : !btree_node_type_needs_gc(btree_id) ? 1
973 b = c->btree_roots[btree_id].b;
975 if (btree_node_fake(b))
978 six_lock_read(&b->c.lock, NULL, NULL);
979 if (mustfix_fsck_err_on(bpos_cmp(b->data->min_key, POS_MIN), c,
980 "btree root with incorrect min_key: %s",
981 (bch2_bpos_to_text(&PBUF(buf), b->data->min_key), buf))) {
982 bch_err(c, "repair unimplemented");
987 if (mustfix_fsck_err_on(bpos_cmp(b->data->max_key, SPOS_MAX), c,
988 "btree root with incorrect max_key: %s",
989 (bch2_bpos_to_text(&PBUF(buf), b->data->max_key), buf))) {
990 bch_err(c, "repair unimplemented");
995 if (b->c.level >= target_depth)
996 ret = bch2_gc_btree_init_recurse(trans, b, target_depth);
999 struct bkey_s_c k = bkey_i_to_s_c(&b->key);
1001 ret = bch2_gc_mark_key(trans, b->c.btree_id, b->c.level, true,
1002 &k, &max_stale, true);
1005 six_unlock_read(&b->c.lock);
1008 bch_err(c, "%s: ret %i", __func__, ret);
1012 static inline int btree_id_gc_phase_cmp(enum btree_id l, enum btree_id r)
1014 return (int) btree_id_to_gc_phase(l) -
1015 (int) btree_id_to_gc_phase(r);
1018 static int bch2_gc_btrees(struct bch_fs *c, bool initial, bool metadata_only)
1020 struct btree_trans trans;
1021 enum btree_id ids[BTREE_ID_NR];
1025 bch2_trans_init(&trans, c, 0, 0);
1027 for (i = 0; i < BTREE_ID_NR; i++)
1029 bubble_sort(ids, BTREE_ID_NR, btree_id_gc_phase_cmp);
1031 for (i = 0; i < BTREE_ID_NR && !ret; i++)
1033 ? bch2_gc_btree_init(&trans, ids[i], metadata_only)
1034 : bch2_gc_btree(&trans, ids[i], initial, metadata_only);
1037 bch_err(c, "%s: ret %i", __func__, ret);
1039 bch2_trans_exit(&trans);
1043 static void mark_metadata_sectors(struct bch_fs *c, struct bch_dev *ca,
1045 enum bch_data_type type,
1048 u64 b = sector_to_bucket(ca, start);
1052 min_t(u64, bucket_to_sector(ca, b + 1), end) - start;
1054 bch2_mark_metadata_bucket(c, ca, b, type, sectors,
1055 gc_phase(GC_PHASE_SB), flags);
1058 } while (start < end);
1061 static void bch2_mark_dev_superblock(struct bch_fs *c, struct bch_dev *ca,
1064 struct bch_sb_layout *layout = &ca->disk_sb.sb->layout;
1068 for (i = 0; i < layout->nr_superblocks; i++) {
1069 u64 offset = le64_to_cpu(layout->sb_offset[i]);
1071 if (offset == BCH_SB_SECTOR)
1072 mark_metadata_sectors(c, ca, 0, BCH_SB_SECTOR,
1073 BCH_DATA_sb, flags);
1075 mark_metadata_sectors(c, ca, offset,
1076 offset + (1 << layout->sb_max_size_bits),
1077 BCH_DATA_sb, flags);
1080 for (i = 0; i < ca->journal.nr; i++) {
1081 b = ca->journal.buckets[i];
1082 bch2_mark_metadata_bucket(c, ca, b, BCH_DATA_journal,
1084 gc_phase(GC_PHASE_SB), flags);
1088 static void bch2_mark_superblocks(struct bch_fs *c)
1093 mutex_lock(&c->sb_lock);
1094 gc_pos_set(c, gc_phase(GC_PHASE_SB));
1096 for_each_online_member(ca, c, i)
1097 bch2_mark_dev_superblock(c, ca, BTREE_TRIGGER_GC);
1098 mutex_unlock(&c->sb_lock);
1102 /* Also see bch2_pending_btree_node_free_insert_done() */
1103 static void bch2_mark_pending_btree_node_frees(struct bch_fs *c)
1105 struct btree_update *as;
1106 struct pending_btree_node_free *d;
1108 mutex_lock(&c->btree_interior_update_lock);
1109 gc_pos_set(c, gc_phase(GC_PHASE_PENDING_DELETE));
1111 for_each_pending_btree_node_free(c, as, d)
1112 if (d->index_update_done)
1113 bch2_mark_key(c, bkey_i_to_s_c(&d->key), BTREE_TRIGGER_GC);
1115 mutex_unlock(&c->btree_interior_update_lock);
1119 static void bch2_gc_free(struct bch_fs *c)
1124 genradix_free(&c->reflink_gc_table);
1125 genradix_free(&c->gc_stripes);
1127 for_each_member_device(ca, c, i) {
1128 kvpfree(rcu_dereference_protected(ca->buckets[1], 1),
1129 sizeof(struct bucket_array) +
1130 ca->mi.nbuckets * sizeof(struct bucket));
1131 ca->buckets[1] = NULL;
1133 free_percpu(ca->usage_gc);
1134 ca->usage_gc = NULL;
1137 free_percpu(c->usage_gc);
1141 static int bch2_gc_done(struct bch_fs *c,
1142 bool initial, bool metadata_only)
1144 struct bch_dev *ca = NULL;
1145 bool verify = !metadata_only && (!initial ||
1146 (c->sb.compat & (1ULL << BCH_COMPAT_alloc_info)));
1150 percpu_down_write(&c->mark_lock);
1152 #define copy_field(_f, _msg, ...) \
1153 if (dst->_f != src->_f) { \
1155 fsck_err(c, _msg ": got %llu, should be %llu" \
1156 , ##__VA_ARGS__, dst->_f, src->_f); \
1157 dst->_f = src->_f; \
1159 #define copy_stripe_field(_f, _msg, ...) \
1160 if (dst->_f != src->_f) { \
1162 fsck_err(c, "stripe %zu has wrong "_msg \
1163 ": got %u, should be %u", \
1164 iter.pos, ##__VA_ARGS__, \
1165 dst->_f, src->_f); \
1166 dst->_f = src->_f; \
1168 #define copy_dev_field(_f, _msg, ...) \
1169 copy_field(_f, "dev %u has wrong " _msg, dev, ##__VA_ARGS__)
1170 #define copy_fs_field(_f, _msg, ...) \
1171 copy_field(_f, "fs has wrong " _msg, ##__VA_ARGS__)
1173 for (i = 0; i < ARRAY_SIZE(c->usage); i++)
1174 bch2_fs_usage_acc_to_base(c, i);
1176 for_each_member_device(ca, c, dev) {
1177 struct bch_dev_usage *dst = ca->usage_base;
1178 struct bch_dev_usage *src = (void *)
1179 bch2_acc_percpu_u64s((void *) ca->usage_gc,
1182 copy_dev_field(buckets_ec, "buckets_ec");
1183 copy_dev_field(buckets_unavailable, "buckets_unavailable");
1185 for (i = 0; i < BCH_DATA_NR; i++) {
1186 copy_dev_field(d[i].buckets, "%s buckets", bch2_data_types[i]);
1187 copy_dev_field(d[i].sectors, "%s sectors", bch2_data_types[i]);
1188 copy_dev_field(d[i].fragmented, "%s fragmented", bch2_data_types[i]);
1193 unsigned nr = fs_usage_u64s(c);
1194 struct bch_fs_usage *dst = c->usage_base;
1195 struct bch_fs_usage *src = (void *)
1196 bch2_acc_percpu_u64s((void *) c->usage_gc, nr);
1198 copy_fs_field(hidden, "hidden");
1199 copy_fs_field(btree, "btree");
1201 if (!metadata_only) {
1202 copy_fs_field(data, "data");
1203 copy_fs_field(cached, "cached");
1204 copy_fs_field(reserved, "reserved");
1205 copy_fs_field(nr_inodes,"nr_inodes");
1207 for (i = 0; i < BCH_REPLICAS_MAX; i++)
1208 copy_fs_field(persistent_reserved[i],
1209 "persistent_reserved[%i]", i);
1212 for (i = 0; i < c->replicas.nr; i++) {
1213 struct bch_replicas_entry *e =
1214 cpu_replicas_entry(&c->replicas, i);
1217 if (metadata_only &&
1218 (e->data_type == BCH_DATA_user ||
1219 e->data_type == BCH_DATA_cached))
1222 bch2_replicas_entry_to_text(&PBUF(buf), e);
1224 copy_fs_field(replicas[i], "%s", buf);
1228 #undef copy_fs_field
1229 #undef copy_dev_field
1230 #undef copy_stripe_field
1234 percpu_ref_put(&ca->ref);
1236 bch_err(c, "%s: ret %i", __func__, ret);
1238 percpu_up_write(&c->mark_lock);
1242 static int bch2_gc_start(struct bch_fs *c,
1245 struct bch_dev *ca = NULL;
1248 BUG_ON(c->usage_gc);
1250 c->usage_gc = __alloc_percpu_gfp(fs_usage_u64s(c) * sizeof(u64),
1251 sizeof(u64), GFP_KERNEL);
1253 bch_err(c, "error allocating c->usage_gc");
1257 for_each_member_device(ca, c, i) {
1258 BUG_ON(ca->buckets[1]);
1259 BUG_ON(ca->usage_gc);
1261 ca->usage_gc = alloc_percpu(struct bch_dev_usage);
1262 if (!ca->usage_gc) {
1263 bch_err(c, "error allocating ca->usage_gc");
1264 percpu_ref_put(&ca->ref);
1272 static int bch2_alloc_write_key(struct btree_trans *trans,
1273 struct btree_iter *iter,
1274 bool initial, bool metadata_only)
1276 struct bch_fs *c = trans->c;
1277 struct bch_dev *ca = bch_dev_bkey_exists(c, iter->pos.inode);
1280 struct bkey_alloc_unpacked old_u, new_u, gc_u;
1281 struct bkey_alloc_buf *a;
1285 * For this to be correct at runtime, we'll need to figure out a way for
1286 * it to actually lock the key in the btree key cache:
1290 ret = bch2_btree_key_cache_flush(trans,
1291 BTREE_ID_alloc, iter->pos);
1296 k = bch2_btree_iter_peek_slot(iter);
1301 old_u = new_u = bch2_alloc_unpack(k);
1303 percpu_down_read(&c->mark_lock);
1304 g = gc_bucket(ca, iter->pos.offset);
1305 gc_u = (struct bkey_alloc_unpacked) {
1306 .dev = iter->pos.inode,
1307 .bucket = iter->pos.offset,
1309 .oldest_gen = g->oldest_gen,
1310 .data_type = g->mark.data_type,
1311 .dirty_sectors = g->mark.dirty_sectors,
1312 .cached_sectors = g->mark.cached_sectors,
1313 .read_time = g->io_time[READ],
1314 .write_time = g->io_time[WRITE],
1315 .stripe = g->stripe,
1316 .stripe_redundancy = g->stripe_redundancy,
1318 percpu_up_read(&c->mark_lock);
1320 if (metadata_only &&
1321 gc_u.data_type != BCH_DATA_sb &&
1322 gc_u.data_type != BCH_DATA_journal &&
1323 gc_u.data_type != BCH_DATA_btree)
1326 if (!bkey_alloc_unpacked_cmp(old_u, gc_u) ||
1327 gen_after(old_u.gen, gc_u.gen))
1330 #define copy_bucket_field(_f) \
1331 if (fsck_err_on(new_u._f != gc_u._f, c, \
1332 "bucket %llu:%llu gen %u data type %s has wrong " #_f \
1333 ": got %u, should be %u", \
1334 iter->pos.inode, iter->pos.offset, \
1336 bch2_data_types[new_u.data_type], \
1337 new_u._f, gc_u._f)) \
1338 new_u._f = gc_u._f; \
1340 copy_bucket_field(gen);
1341 copy_bucket_field(data_type);
1342 copy_bucket_field(stripe);
1343 copy_bucket_field(dirty_sectors);
1344 copy_bucket_field(cached_sectors);
1345 copy_bucket_field(stripe_redundancy);
1346 copy_bucket_field(stripe);
1347 #undef copy_bucket_field
1349 new_u.oldest_gen = gc_u.oldest_gen;
1351 if (!bkey_alloc_unpacked_cmp(old_u, new_u))
1354 a = bch2_alloc_pack(trans, new_u);
1359 ? bch2_journal_key_insert(c, BTREE_ID_alloc, 0, &a->k)
1360 : bch2_trans_update(trans, iter, &a->k, BTREE_TRIGGER_NORUN);
1365 static int bch2_gc_alloc_done(struct bch_fs *c, bool initial, bool metadata_only)
1367 struct btree_trans trans;
1368 struct btree_iter iter;
1374 bch2_trans_init(&trans, c, 0, 0);
1376 for_each_member_device(ca, c, i) {
1377 for_each_btree_key(&trans, iter, BTREE_ID_alloc,
1378 POS(ca->dev_idx, ca->mi.first_bucket),
1380 BTREE_ITER_PREFETCH, k, ret) {
1381 if (bkey_cmp(iter.pos, POS(ca->dev_idx, ca->mi.nbuckets)) >= 0)
1384 ret = __bch2_trans_do(&trans, NULL, NULL,
1385 BTREE_INSERT_LAZY_RW,
1386 bch2_alloc_write_key(&trans, &iter,
1387 initial, metadata_only));
1391 bch2_trans_iter_exit(&trans, &iter);
1394 bch_err(c, "error writing alloc info: %i", ret);
1395 percpu_ref_put(&ca->ref);
1400 bch2_trans_exit(&trans);
1404 static int bch2_gc_alloc_start(struct bch_fs *c, bool initial, bool metadata_only)
1409 for_each_member_device(ca, c, i) {
1410 struct bucket_array *buckets = kvpmalloc(sizeof(struct bucket_array) +
1411 ca->mi.nbuckets * sizeof(struct bucket),
1412 GFP_KERNEL|__GFP_ZERO);
1414 percpu_ref_put(&ca->ref);
1415 percpu_up_write(&c->mark_lock);
1416 bch_err(c, "error allocating ca->buckets[gc]");
1420 buckets->first_bucket = ca->mi.first_bucket;
1421 buckets->nbuckets = ca->mi.nbuckets;
1422 rcu_assign_pointer(ca->buckets[1], buckets);
1425 return bch2_alloc_read(c, true, metadata_only);
1428 static int bch2_gc_reflink_done(struct bch_fs *c, bool initial,
1431 struct btree_trans trans;
1432 struct btree_iter iter;
1434 struct reflink_gc *r;
1442 bch2_trans_init(&trans, c, 0, 0);
1444 for_each_btree_key(&trans, iter, BTREE_ID_reflink, POS_MIN,
1445 BTREE_ITER_PREFETCH, k, ret) {
1446 const __le64 *refcount = bkey_refcount_c(k);
1451 r = genradix_ptr(&c->reflink_gc_table, idx++);
1453 r->offset != k.k->p.offset ||
1454 r->size != k.k->size) {
1455 bch_err(c, "unexpected inconsistency walking reflink table at gc finish");
1460 if (fsck_err_on(r->refcount != le64_to_cpu(*refcount), c,
1461 "reflink key has wrong refcount:\n"
1464 (bch2_bkey_val_to_text(&PBUF(buf), c, k), buf),
1468 new = kmalloc(bkey_bytes(k.k), GFP_KERNEL);
1474 bkey_reassemble(new, k);
1477 new->k.type = KEY_TYPE_deleted;
1479 *bkey_refcount(new) = cpu_to_le64(r->refcount);
1482 ? bch2_journal_key_insert(c, BTREE_ID_stripes, 0, new)
1483 : __bch2_trans_do(&trans, NULL, NULL, 0,
1484 __bch2_btree_insert(&trans, BTREE_ID_reflink, new));
1492 bch2_trans_iter_exit(&trans, &iter);
1493 c->reflink_gc_nr = 0;
1494 bch2_trans_exit(&trans);
1498 static int bch2_gc_reflink_start(struct bch_fs *c, bool initial,
1501 struct btree_trans trans;
1502 struct btree_iter iter;
1504 struct reflink_gc *r;
1510 bch2_trans_init(&trans, c, 0, 0);
1511 c->reflink_gc_nr = 0;
1513 for_each_btree_key(&trans, iter, BTREE_ID_reflink, POS_MIN,
1514 BTREE_ITER_PREFETCH, k, ret) {
1515 const __le64 *refcount = bkey_refcount_c(k);
1520 r = genradix_ptr_alloc(&c->reflink_gc_table, c->reflink_gc_nr++,
1527 r->offset = k.k->p.offset;
1528 r->size = k.k->size;
1531 bch2_trans_iter_exit(&trans, &iter);
1533 bch2_trans_exit(&trans);
1537 static int bch2_gc_stripes_done(struct bch_fs *c, bool initial,
1540 struct btree_trans trans;
1541 struct btree_iter iter;
1543 struct gc_stripe *m;
1544 const struct bch_stripe *s;
1552 bch2_trans_init(&trans, c, 0, 0);
1554 for_each_btree_key(&trans, iter, BTREE_ID_stripes, POS_MIN,
1555 BTREE_ITER_PREFETCH, k, ret) {
1556 if (k.k->type != KEY_TYPE_stripe)
1559 s = bkey_s_c_to_stripe(k).v;
1560 m = genradix_ptr(&c->gc_stripes, k.k->p.offset);
1562 for (i = 0; i < s->nr_blocks; i++)
1563 if (stripe_blockcount_get(s, i) != (m ? m->block_sectors[i] : 0))
1567 if (fsck_err_on(true, c,
1568 "stripe has wrong block sector count %u:\n"
1571 (bch2_bkey_val_to_text(&PBUF(buf), c, k), buf),
1572 m ? m->block_sectors[i] : 0)) {
1573 struct bkey_i_stripe *new;
1575 new = kmalloc(bkey_bytes(k.k), GFP_KERNEL);
1581 bkey_reassemble(&new->k_i, k);
1583 for (i = 0; i < new->v.nr_blocks; i++)
1584 stripe_blockcount_set(&new->v, i, m ? m->block_sectors[i] : 0);
1587 ? bch2_journal_key_insert(c, BTREE_ID_stripes, 0, &new->k_i)
1588 : __bch2_trans_do(&trans, NULL, NULL, 0,
1589 __bch2_btree_insert(&trans, BTREE_ID_reflink, &new->k_i));
1594 bch2_trans_iter_exit(&trans, &iter);
1596 bch2_trans_exit(&trans);
1601 * bch2_gc - walk _all_ references to buckets, and recompute them:
1603 * Order matters here:
1604 * - Concurrent GC relies on the fact that we have a total ordering for
1605 * everything that GC walks - see gc_will_visit_node(),
1606 * gc_will_visit_root()
1608 * - also, references move around in the course of index updates and
1609 * various other crap: everything needs to agree on the ordering
1610 * references are allowed to move around in - e.g., we're allowed to
1611 * start with a reference owned by an open_bucket (the allocator) and
1612 * move it to the btree, but not the reverse.
1614 * This is necessary to ensure that gc doesn't miss references that
1615 * move around - if references move backwards in the ordering GC
1616 * uses, GC could skip past them
1618 int bch2_gc(struct bch_fs *c, bool initial, bool metadata_only)
1621 u64 start_time = local_clock();
1622 unsigned i, iter = 0;
1625 lockdep_assert_held(&c->state_lock);
1628 down_write(&c->gc_lock);
1630 /* flush interior btree updates: */
1631 closure_wait_event(&c->btree_interior_update_wait,
1632 !bch2_btree_interior_updates_nr_pending(c));
1634 ret = bch2_gc_start(c, metadata_only) ?:
1635 bch2_gc_alloc_start(c, initial, metadata_only) ?:
1636 bch2_gc_reflink_start(c, initial, metadata_only);
1640 gc_pos_set(c, gc_phase(GC_PHASE_START));
1642 bch2_mark_superblocks(c);
1644 if (BCH_SB_HAS_TOPOLOGY_ERRORS(c->disk_sb.sb) &&
1645 !test_bit(BCH_FS_INITIAL_GC_DONE, &c->flags) &&
1646 c->opts.fix_errors != FSCK_OPT_NO) {
1647 bch_info(c, "starting topology repair pass");
1648 ret = bch2_repair_topology(c);
1651 bch_info(c, "topology repair pass done");
1653 set_bit(BCH_FS_TOPOLOGY_REPAIR_DONE, &c->flags);
1656 ret = bch2_gc_btrees(c, initial, metadata_only);
1658 if (ret == FSCK_ERR_START_TOPOLOGY_REPAIR &&
1659 !test_bit(BCH_FS_TOPOLOGY_REPAIR_DONE, &c->flags) &&
1660 !test_bit(BCH_FS_INITIAL_GC_DONE, &c->flags)) {
1661 set_bit(BCH_FS_NEED_ANOTHER_GC, &c->flags);
1665 if (ret == FSCK_ERR_START_TOPOLOGY_REPAIR)
1666 ret = FSCK_ERR_EXIT;
1672 bch2_mark_pending_btree_node_frees(c);
1676 if (test_bit(BCH_FS_NEED_ANOTHER_GC, &c->flags) ||
1677 (!iter && bch2_test_restart_gc)) {
1679 * XXX: make sure gens we fixed got saved
1682 bch_info(c, "Second GC pass needed, restarting:");
1683 clear_bit(BCH_FS_NEED_ANOTHER_GC, &c->flags);
1684 __gc_pos_set(c, gc_phase(GC_PHASE_NOT_RUNNING));
1686 percpu_down_write(&c->mark_lock);
1688 percpu_up_write(&c->mark_lock);
1689 /* flush fsck errors, reset counters */
1690 bch2_flush_fsck_errs(c);
1695 bch_info(c, "Unable to fix bucket gens, looping");
1700 bch2_journal_block(&c->journal);
1702 ret = bch2_gc_stripes_done(c, initial, metadata_only) ?:
1703 bch2_gc_reflink_done(c, initial, metadata_only) ?:
1704 bch2_gc_alloc_done(c, initial, metadata_only) ?:
1705 bch2_gc_done(c, initial, metadata_only);
1707 bch2_journal_unblock(&c->journal);
1710 percpu_down_write(&c->mark_lock);
1711 /* Indicates that gc is no longer in progress: */
1712 __gc_pos_set(c, gc_phase(GC_PHASE_NOT_RUNNING));
1715 percpu_up_write(&c->mark_lock);
1717 up_write(&c->gc_lock);
1720 bch2_time_stats_update(&c->times[BCH_TIME_btree_gc], start_time);
1723 * Wake up allocator in case it was waiting for buckets
1724 * because of not being able to inc gens
1726 for_each_member_device(ca, c, i)
1727 bch2_wake_allocator(ca);
1730 * At startup, allocations can happen directly instead of via the
1731 * allocator thread - issue wakeup in case they blocked on gc_lock:
1733 closure_wake_up(&c->freelist_wait);
1737 static bool gc_btree_gens_key(struct bch_fs *c, struct bkey_s_c k)
1739 struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
1740 const struct bch_extent_ptr *ptr;
1742 percpu_down_read(&c->mark_lock);
1743 bkey_for_each_ptr(ptrs, ptr) {
1744 struct bch_dev *ca = bch_dev_bkey_exists(c, ptr->dev);
1745 struct bucket *g = PTR_BUCKET(ca, ptr);
1747 if (gen_after(g->mark.gen, ptr->gen) > 16) {
1748 percpu_up_read(&c->mark_lock);
1753 bkey_for_each_ptr(ptrs, ptr) {
1754 struct bch_dev *ca = bch_dev_bkey_exists(c, ptr->dev);
1755 struct bucket *g = PTR_BUCKET(ca, ptr);
1757 if (gen_after(g->gc_gen, ptr->gen))
1758 g->gc_gen = ptr->gen;
1760 percpu_up_read(&c->mark_lock);
1766 * For recalculating oldest gen, we only need to walk keys in leaf nodes; btree
1767 * node pointers currently never have cached pointers that can become stale:
1769 static int bch2_gc_btree_gens(struct bch_fs *c, enum btree_id btree_id)
1771 struct btree_trans trans;
1772 struct btree_iter iter;
1775 int ret = 0, commit_err = 0;
1777 bch2_bkey_buf_init(&sk);
1778 bch2_trans_init(&trans, c, 0, 0);
1780 bch2_trans_iter_init(&trans, &iter, btree_id, POS_MIN,
1781 BTREE_ITER_PREFETCH|
1782 BTREE_ITER_NOT_EXTENTS|
1783 BTREE_ITER_ALL_SNAPSHOTS);
1785 while ((bch2_trans_begin(&trans),
1786 k = bch2_btree_iter_peek(&iter)).k) {
1794 c->gc_gens_pos = iter.pos;
1796 if (gc_btree_gens_key(c, k) && !commit_err) {
1797 bch2_bkey_buf_reassemble(&sk, c, k);
1798 bch2_extent_normalize(c, bkey_i_to_s(sk.k));
1801 bch2_trans_update(&trans, &iter, sk.k, 0) ?:
1802 bch2_trans_commit(&trans, NULL, NULL,
1803 BTREE_INSERT_NOWAIT|
1804 BTREE_INSERT_NOFAIL);
1805 if (commit_err == -EINTR) {
1811 bch2_btree_iter_advance(&iter);
1813 bch2_trans_iter_exit(&trans, &iter);
1815 bch2_trans_exit(&trans);
1816 bch2_bkey_buf_exit(&sk, c);
1821 int bch2_gc_gens(struct bch_fs *c)
1824 struct bucket_array *buckets;
1826 u64 start_time = local_clock();
1831 * Ideally we would be using state_lock and not gc_lock here, but that
1832 * introduces a deadlock in the RO path - we currently take the state
1833 * lock at the start of going RO, thus the gc thread may get stuck:
1835 down_read(&c->gc_lock);
1837 for_each_member_device(ca, c, i) {
1838 down_read(&ca->bucket_lock);
1839 buckets = bucket_array(ca);
1841 for_each_bucket(g, buckets)
1842 g->gc_gen = g->mark.gen;
1843 up_read(&ca->bucket_lock);
1846 for (i = 0; i < BTREE_ID_NR; i++)
1847 if ((1 << i) & BTREE_ID_HAS_PTRS) {
1848 c->gc_gens_btree = i;
1849 c->gc_gens_pos = POS_MIN;
1850 ret = bch2_gc_btree_gens(c, i);
1852 bch_err(c, "error recalculating oldest_gen: %i", ret);
1857 for_each_member_device(ca, c, i) {
1858 down_read(&ca->bucket_lock);
1859 buckets = bucket_array(ca);
1861 for_each_bucket(g, buckets)
1862 g->oldest_gen = g->gc_gen;
1863 up_read(&ca->bucket_lock);
1866 c->gc_gens_btree = 0;
1867 c->gc_gens_pos = POS_MIN;
1871 bch2_time_stats_update(&c->times[BCH_TIME_btree_gc], start_time);
1873 up_read(&c->gc_lock);
1877 static int bch2_gc_thread(void *arg)
1879 struct bch_fs *c = arg;
1880 struct io_clock *clock = &c->io_clock[WRITE];
1881 unsigned long last = atomic64_read(&clock->now);
1882 unsigned last_kick = atomic_read(&c->kick_gc);
1889 set_current_state(TASK_INTERRUPTIBLE);
1891 if (kthread_should_stop()) {
1892 __set_current_state(TASK_RUNNING);
1896 if (atomic_read(&c->kick_gc) != last_kick)
1899 if (c->btree_gc_periodic) {
1900 unsigned long next = last + c->capacity / 16;
1902 if (atomic64_read(&clock->now) >= next)
1905 bch2_io_clock_schedule_timeout(clock, next);
1912 __set_current_state(TASK_RUNNING);
1914 last = atomic64_read(&clock->now);
1915 last_kick = atomic_read(&c->kick_gc);
1918 * Full gc is currently incompatible with btree key cache:
1921 ret = bch2_gc(c, false, false);
1923 ret = bch2_gc_gens(c);
1926 bch_err(c, "btree gc failed: %i", ret);
1928 debug_check_no_locks_held();
1934 void bch2_gc_thread_stop(struct bch_fs *c)
1936 struct task_struct *p;
1939 c->gc_thread = NULL;
1947 int bch2_gc_thread_start(struct bch_fs *c)
1949 struct task_struct *p;
1954 p = kthread_create(bch2_gc_thread, c, "bch-gc/%s", c->name);
1956 bch_err(c, "error creating gc thread: %li", PTR_ERR(p));