1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2010 Kent Overstreet <kent.overstreet@gmail.com>
4 * Copyright (C) 2014 Datera Inc.
5 */
6
7#include "bcachefs.h"
8#include "alloc_background.h"
9#include "alloc_foreground.h"
10#include "backpointers.h"
11#include "bkey_methods.h"
12#include "bkey_buf.h"
13#include "btree_journal_iter.h"
14#include "btree_key_cache.h"
15#include "btree_locking.h"
16#include "btree_node_scan.h"
17#include "btree_update_interior.h"
18#include "btree_io.h"
19#include "btree_gc.h"
20#include "buckets.h"
21#include "clock.h"
22#include "debug.h"
23#include "ec.h"
24#include "error.h"
25#include "extents.h"
26#include "journal.h"
27#include "keylist.h"
28#include "move.h"
29#include "recovery_passes.h"
30#include "reflink.h"
31#include "replicas.h"
32#include "super-io.h"
33#include "trace.h"
34
35#include <linux/slab.h>
36#include <linux/bitops.h>
37#include <linux/freezer.h>
38#include <linux/kthread.h>
39#include <linux/preempt.h>
40#include <linux/rcupdate.h>
41#include <linux/sched/task.h>
42
43#define DROP_THIS_NODE 10
44#define DROP_PREV_NODE 11
45#define DID_FILL_FROM_SCAN 12
46
47static struct bkey_s unsafe_bkey_s_c_to_s(struct bkey_s_c k)
48{
49 return (struct bkey_s) {{{
50 (struct bkey *) k.k,
51 (struct bch_val *) k.v
52 }}};
53}
54
55static bool should_restart_for_topology_repair(struct bch_fs *c)
56{
57 return c->opts.fix_errors != FSCK_FIX_no &&
58 !(c->recovery_passes_complete & BIT_ULL(BCH_RECOVERY_PASS_check_topology));
59}
60
61static inline void __gc_pos_set(struct bch_fs *c, struct gc_pos new_pos)
62{
63 preempt_disable();
64 write_seqcount_begin(&c->gc_pos_lock);
65 c->gc_pos = new_pos;
66 write_seqcount_end(&c->gc_pos_lock);
67 preempt_enable();
68}
69
70static inline void gc_pos_set(struct bch_fs *c, struct gc_pos new_pos)
71{
72 BUG_ON(gc_pos_cmp(new_pos, c->gc_pos) <= 0);
73 __gc_pos_set(c, new_pos);
74}
75
76static void btree_ptr_to_v2(struct btree *b, struct bkey_i_btree_ptr_v2 *dst)
77{
78 switch (b->key.k.type) {
79 case KEY_TYPE_btree_ptr: {
80 struct bkey_i_btree_ptr *src = bkey_i_to_btree_ptr(k: &b->key);
81
82 dst->k.p = src->k.p;
83 dst->v.mem_ptr = 0;
84 dst->v.seq = b->data->keys.seq;
85 dst->v.sectors_written = 0;
86 dst->v.flags = 0;
87 dst->v.min_key = b->data->min_key;
88 set_bkey_val_bytes(k: &dst->k, bytes: sizeof(dst->v) + bkey_val_bytes(k: &src->k));
89 memcpy(dst->v.start, src->v.start, bkey_val_bytes(&src->k));
90 break;
91 }
92 case KEY_TYPE_btree_ptr_v2:
93 bkey_copy(dst: &dst->k_i, src: &b->key);
94 break;
95 default:
96 BUG();
97 }
98}
99
100static void bch2_btree_node_update_key_early(struct btree_trans *trans,
101 enum btree_id btree, unsigned level,
102 struct bkey_s_c old, struct bkey_i *new)
103{
104 struct bch_fs *c = trans->c;
105 struct btree *b;
106 struct bkey_buf tmp;
107 int ret;
108
109 bch2_bkey_buf_init(s: &tmp);
110 bch2_bkey_buf_reassemble(s: &tmp, c, k: old);
111
112 b = bch2_btree_node_get_noiter(trans, tmp.k, btree, level, true);
113 if (!IS_ERR_OR_NULL(ptr: b)) {
114 mutex_lock(&c->btree_cache.lock);
115
116 bch2_btree_node_hash_remove(&c->btree_cache, b);
117
118 bkey_copy(dst: &b->key, src: new);
119 ret = __bch2_btree_node_hash_insert(&c->btree_cache, b);
120 BUG_ON(ret);
121
122 mutex_unlock(lock: &c->btree_cache.lock);
123 six_unlock_read(lock: &b->c.lock);
124 }
125
126 bch2_bkey_buf_exit(s: &tmp, c);
127}
128
129static int set_node_min(struct bch_fs *c, struct btree *b, struct bpos new_min)
130{
131 struct bkey_i_btree_ptr_v2 *new;
132 int ret;
133
134 if (c->opts.verbose) {
135 struct printbuf buf = PRINTBUF;
136
137 bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(k: &b->key));
138 prt_str(out: &buf, str: " -> ");
139 bch2_bpos_to_text(&buf, new_min);
140
141 bch_info(c, "%s(): %s", __func__, buf.buf);
142 printbuf_exit(&buf);
143 }
144
145 new = kmalloc_array(BKEY_BTREE_PTR_U64s_MAX, size: sizeof(u64), GFP_KERNEL);
146 if (!new)
147 return -BCH_ERR_ENOMEM_gc_repair_key;
148
149 btree_ptr_to_v2(b, dst: new);
150 b->data->min_key = new_min;
151 new->v.min_key = new_min;
152 SET_BTREE_PTR_RANGE_UPDATED(k: &new->v, v: true);
153
154 ret = bch2_journal_key_insert_take(c, b->c.btree_id, b->c.level + 1, &new->k_i);
155 if (ret) {
156 kfree(objp: new);
157 return ret;
158 }
159
160 bch2_btree_node_drop_keys_outside_node(b);
161 bkey_copy(dst: &b->key, src: &new->k_i);
162 return 0;
163}
164
165static int set_node_max(struct bch_fs *c, struct btree *b, struct bpos new_max)
166{
167 struct bkey_i_btree_ptr_v2 *new;
168 int ret;
169
170 if (c->opts.verbose) {
171 struct printbuf buf = PRINTBUF;
172
173 bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(k: &b->key));
174 prt_str(out: &buf, str: " -> ");
175 bch2_bpos_to_text(&buf, new_max);
176
177 bch_info(c, "%s(): %s", __func__, buf.buf);
178 printbuf_exit(&buf);
179 }
180
181 ret = bch2_journal_key_delete(c, b->c.btree_id, b->c.level + 1, b->key.k.p);
182 if (ret)
183 return ret;
184
185 new = kmalloc_array(BKEY_BTREE_PTR_U64s_MAX, size: sizeof(u64), GFP_KERNEL);
186 if (!new)
187 return -BCH_ERR_ENOMEM_gc_repair_key;
188
189 btree_ptr_to_v2(b, dst: new);
190 b->data->max_key = new_max;
191 new->k.p = new_max;
192 SET_BTREE_PTR_RANGE_UPDATED(k: &new->v, v: true);
193
194 ret = bch2_journal_key_insert_take(c, b->c.btree_id, b->c.level + 1, &new->k_i);
195 if (ret) {
196 kfree(objp: new);
197 return ret;
198 }
199
200 bch2_btree_node_drop_keys_outside_node(b);
201
202 mutex_lock(&c->btree_cache.lock);
203 bch2_btree_node_hash_remove(&c->btree_cache, b);
204
205 bkey_copy(dst: &b->key, src: &new->k_i);
206 ret = __bch2_btree_node_hash_insert(&c->btree_cache, b);
207 BUG_ON(ret);
208 mutex_unlock(lock: &c->btree_cache.lock);
209 return 0;
210}
211
212static int btree_check_node_boundaries(struct bch_fs *c, struct btree *b,
213 struct btree *prev, struct btree *cur,
214 struct bpos *pulled_from_scan)
215{
216 struct bpos expected_start = !prev
217 ? b->data->min_key
218 : bpos_successor(p: prev->key.k.p);
219 struct printbuf buf = PRINTBUF;
220 int ret = 0;
221
222 BUG_ON(b->key.k.type == KEY_TYPE_btree_ptr_v2 &&
223 !bpos_eq(bkey_i_to_btree_ptr_v2(&b->key)->v.min_key,
224 b->data->min_key));
225
226 if (bpos_eq(l: expected_start, r: cur->data->min_key))
227 return 0;
228
229 prt_printf(&buf, " at btree %s level %u:\n parent: ",
230 bch2_btree_id_str(b->c.btree_id), b->c.level);
231 bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(k: &b->key));
232
233 if (prev) {
234 prt_printf(&buf, "\n prev: ");
235 bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(k: &prev->key));
236 }
237
238 prt_str(out: &buf, str: "\n next: ");
239 bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(k: &cur->key));
240
241 if (bpos_lt(l: expected_start, r: cur->data->min_key)) { /* gap */
242 if (b->c.level == 1 &&
243 bpos_lt(l: *pulled_from_scan, r: cur->data->min_key)) {
244 ret = bch2_get_scanned_nodes(c, b->c.btree_id, 0,
245 expected_start,
246 bpos_predecessor(p: cur->data->min_key));
247 if (ret)
248 goto err;
249
250 *pulled_from_scan = cur->data->min_key;
251 ret = DID_FILL_FROM_SCAN;
252 } else {
253 if (mustfix_fsck_err(c, btree_node_topology_bad_min_key,
254 "btree node with incorrect min_key%s", buf.buf))
255 ret = set_node_min(c, b: cur, new_min: expected_start);
256 }
257 } else { /* overlap */
258 if (prev && BTREE_NODE_SEQ(k: cur->data) > BTREE_NODE_SEQ(k: prev->data)) { /* cur overwrites prev */
259 if (bpos_ge(l: prev->data->min_key, r: cur->data->min_key)) { /* fully? */
260 if (mustfix_fsck_err(c, btree_node_topology_overwritten_by_next_node,
261 "btree node overwritten by next node%s", buf.buf))
262 ret = DROP_PREV_NODE;
263 } else {
264 if (mustfix_fsck_err(c, btree_node_topology_bad_max_key,
265 "btree node with incorrect max_key%s", buf.buf))
266 ret = set_node_max(c, b: prev,
267 new_max: bpos_predecessor(p: cur->data->min_key));
268 }
269 } else {
270 if (bpos_ge(l: expected_start, r: cur->data->max_key)) { /* fully? */
271 if (mustfix_fsck_err(c, btree_node_topology_overwritten_by_prev_node,
272 "btree node overwritten by prev node%s", buf.buf))
273 ret = DROP_THIS_NODE;
274 } else {
275 if (mustfix_fsck_err(c, btree_node_topology_bad_min_key,
276 "btree node with incorrect min_key%s", buf.buf))
277 ret = set_node_min(c, b: cur, new_min: expected_start);
278 }
279 }
280 }
281err:
282fsck_err:
283 printbuf_exit(&buf);
284 return ret;
285}
286
287static int btree_repair_node_end(struct bch_fs *c, struct btree *b,
288 struct btree *child, struct bpos *pulled_from_scan)
289{
290 struct printbuf buf = PRINTBUF;
291 int ret = 0;
292
293 if (bpos_eq(l: child->key.k.p, r: b->key.k.p))
294 return 0;
295
296 prt_printf(&buf, "at btree %s level %u:\n parent: ",
297 bch2_btree_id_str(b->c.btree_id), b->c.level);
298 bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(k: &b->key));
299
300 prt_str(out: &buf, str: "\n child: ");
301 bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(k: &child->key));
302
303 if (mustfix_fsck_err(c, btree_node_topology_bad_max_key,
304 "btree node with incorrect max_key%s", buf.buf)) {
305 if (b->c.level == 1 &&
306 bpos_lt(l: *pulled_from_scan, r: b->key.k.p)) {
307 ret = bch2_get_scanned_nodes(c, b->c.btree_id, 0,
308 bpos_successor(p: child->key.k.p), b->key.k.p);
309 if (ret)
310 goto err;
311
312 *pulled_from_scan = b->key.k.p;
313 ret = DID_FILL_FROM_SCAN;
314 } else {
315 ret = set_node_max(c, b: child, new_max: b->key.k.p);
316 }
317 }
318err:
319fsck_err:
320 printbuf_exit(&buf);
321 return ret;
322}
323
324static int bch2_btree_repair_topology_recurse(struct btree_trans *trans, struct btree *b,
325 struct bpos *pulled_from_scan)
326{
327 struct bch_fs *c = trans->c;
328 struct btree_and_journal_iter iter;
329 struct bkey_s_c k;
330 struct bkey_buf prev_k, cur_k;
331 struct btree *prev = NULL, *cur = NULL;
332 bool have_child, new_pass = false;
333 struct printbuf buf = PRINTBUF;
334 int ret = 0;
335
336 if (!b->c.level)
337 return 0;
338
339 bch2_bkey_buf_init(s: &prev_k);
340 bch2_bkey_buf_init(s: &cur_k);
341again:
342 cur = prev = NULL;
343 have_child = new_pass = false;
344 bch2_btree_and_journal_iter_init_node_iter(trans, &iter, b);
345 iter.prefetch = true;
346
347 while ((k = bch2_btree_and_journal_iter_peek(&iter)).k) {
348 BUG_ON(bpos_lt(k.k->p, b->data->min_key));
349 BUG_ON(bpos_gt(k.k->p, b->data->max_key));
350
351 bch2_btree_and_journal_iter_advance(&iter);
352 bch2_bkey_buf_reassemble(s: &cur_k, c, k);
353
354 cur = bch2_btree_node_get_noiter(trans, cur_k.k,
355 b->c.btree_id, b->c.level - 1,
356 false);
357 ret = PTR_ERR_OR_ZERO(ptr: cur);
358
359 printbuf_reset(buf: &buf);
360 bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(k: cur_k.k));
361
362 if (mustfix_fsck_err_on(bch2_err_matches(ret, EIO), c,
363 btree_node_unreadable,
364 "Topology repair: unreadable btree node at btree %s level %u:\n"
365 " %s",
366 bch2_btree_id_str(b->c.btree_id),
367 b->c.level - 1,
368 buf.buf)) {
369 bch2_btree_node_evict(trans, cur_k.k);
370 cur = NULL;
371 ret = bch2_journal_key_delete(c, b->c.btree_id,
372 b->c.level, cur_k.k->k.p);
373 if (ret)
374 break;
375
376 if (!btree_id_is_alloc(id: b->c.btree_id)) {
377 ret = bch2_run_explicit_recovery_pass(c, BCH_RECOVERY_PASS_scan_for_btree_nodes);
378 if (ret)
379 break;
380 }
381 continue;
382 }
383
384 bch_err_msg(c, ret, "getting btree node");
385 if (ret)
386 break;
387
388 if (bch2_btree_node_is_stale(c, cur)) {
389 bch_info(c, "btree node %s older than nodes found by scanning", buf.buf);
390 six_unlock_read(lock: &cur->c.lock);
391 bch2_btree_node_evict(trans, cur_k.k);
392 ret = bch2_journal_key_delete(c, b->c.btree_id,
393 b->c.level, cur_k.k->k.p);
394 cur = NULL;
395 if (ret)
396 break;
397 continue;
398 }
399
400 ret = btree_check_node_boundaries(c, b, prev, cur, pulled_from_scan);
401 if (ret == DID_FILL_FROM_SCAN) {
402 new_pass = true;
403 ret = 0;
404 }
405
406 if (ret == DROP_THIS_NODE) {
407 six_unlock_read(lock: &cur->c.lock);
408 bch2_btree_node_evict(trans, cur_k.k);
409 ret = bch2_journal_key_delete(c, b->c.btree_id,
410 b->c.level, cur_k.k->k.p);
411 cur = NULL;
412 if (ret)
413 break;
414 continue;
415 }
416
417 if (prev)
418 six_unlock_read(lock: &prev->c.lock);
419 prev = NULL;
420
421 if (ret == DROP_PREV_NODE) {
422 bch_info(c, "dropped prev node");
423 bch2_btree_node_evict(trans, prev_k.k);
424 ret = bch2_journal_key_delete(c, b->c.btree_id,
425 b->c.level, prev_k.k->k.p);
426 if (ret)
427 break;
428
429 bch2_btree_and_journal_iter_exit(&iter);
430 goto again;
431 } else if (ret)
432 break;
433
434 prev = cur;
435 cur = NULL;
436 bch2_bkey_buf_copy(s: &prev_k, c, src: cur_k.k);
437 }
438
439 if (!ret && !IS_ERR_OR_NULL(ptr: prev)) {
440 BUG_ON(cur);
441 ret = btree_repair_node_end(c, b, child: prev, pulled_from_scan);
442 if (ret == DID_FILL_FROM_SCAN) {
443 new_pass = true;
444 ret = 0;
445 }
446 }
447
448 if (!IS_ERR_OR_NULL(ptr: prev))
449 six_unlock_read(lock: &prev->c.lock);
450 prev = NULL;
451 if (!IS_ERR_OR_NULL(ptr: cur))
452 six_unlock_read(lock: &cur->c.lock);
453 cur = NULL;
454
455 if (ret)
456 goto err;
457
458 bch2_btree_and_journal_iter_exit(&iter);
459
460 if (new_pass)
461 goto again;
462
463 bch2_btree_and_journal_iter_init_node_iter(trans, &iter, b);
464 iter.prefetch = true;
465
466 while ((k = bch2_btree_and_journal_iter_peek(&iter)).k) {
467 bch2_bkey_buf_reassemble(s: &cur_k, c, k);
468 bch2_btree_and_journal_iter_advance(&iter);
469
470 cur = bch2_btree_node_get_noiter(trans, cur_k.k,
471 b->c.btree_id, b->c.level - 1,
472 false);
473 ret = PTR_ERR_OR_ZERO(ptr: cur);
474
475 bch_err_msg(c, ret, "getting btree node");
476 if (ret)
477 goto err;
478
479 ret = bch2_btree_repair_topology_recurse(trans, b: cur, pulled_from_scan);
480 six_unlock_read(lock: &cur->c.lock);
481 cur = NULL;
482
483 if (ret == DROP_THIS_NODE) {
484 bch2_btree_node_evict(trans, cur_k.k);
485 ret = bch2_journal_key_delete(c, b->c.btree_id,
486 b->c.level, cur_k.k->k.p);
487 new_pass = true;
488 }
489
490 if (ret)
491 goto err;
492
493 have_child = true;
494 }
495
496 printbuf_reset(buf: &buf);
497 bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(k: &b->key));
498
499 if (mustfix_fsck_err_on(!have_child, c,
500 btree_node_topology_interior_node_empty,
501 "empty interior btree node at btree %s level %u\n"
502 " %s",
503 bch2_btree_id_str(b->c.btree_id),
504 b->c.level, buf.buf))
505 ret = DROP_THIS_NODE;
506err:
507fsck_err:
508 if (!IS_ERR_OR_NULL(ptr: prev))
509 six_unlock_read(lock: &prev->c.lock);
510 if (!IS_ERR_OR_NULL(ptr: cur))
511 six_unlock_read(lock: &cur->c.lock);
512
513 bch2_btree_and_journal_iter_exit(&iter);
514
515 if (!ret && new_pass)
516 goto again;
517
518 BUG_ON(!ret && bch2_btree_node_check_topology(trans, b));
519
520 bch2_bkey_buf_exit(s: &prev_k, c);
521 bch2_bkey_buf_exit(s: &cur_k, c);
522 printbuf_exit(&buf);
523 return ret;
524}
525
526int bch2_check_topology(struct bch_fs *c)
527{
528 struct btree_trans *trans = bch2_trans_get(c);
529 struct bpos pulled_from_scan = POS_MIN;
530 int ret = 0;
531
532 for (unsigned i = 0; i < btree_id_nr_alive(c) && !ret; i++) {
533 struct btree_root *r = bch2_btree_id_root(c, id: i);
534 bool reconstructed_root = false;
535
536 if (r->error) {
537 ret = bch2_run_explicit_recovery_pass(c, BCH_RECOVERY_PASS_scan_for_btree_nodes);
538 if (ret)
539 break;
540reconstruct_root:
541 bch_info(c, "btree root %s unreadable, must recover from scan", bch2_btree_id_str(i));
542
543 r->alive = false;
544 r->error = 0;
545
546 if (!bch2_btree_has_scanned_nodes(c, i)) {
547 mustfix_fsck_err(c, btree_root_unreadable_and_scan_found_nothing,
548 "no nodes found for btree %s, continue?", bch2_btree_id_str(i));
549 bch2_btree_root_alloc_fake(c, i, 0);
550 } else {
551 bch2_btree_root_alloc_fake(c, i, 1);
552 bch2_shoot_down_journal_keys(c, i, 1, BTREE_MAX_DEPTH, POS_MIN, SPOS_MAX);
553 ret = bch2_get_scanned_nodes(c, i, 0, POS_MIN, SPOS_MAX);
554 if (ret)
555 break;
556 }
557
558 reconstructed_root = true;
559 }
560
561 struct btree *b = r->b;
562
563 btree_node_lock_nopath_nofail(trans, b: &b->c, type: SIX_LOCK_read);
564 ret = bch2_btree_repair_topology_recurse(trans, b, pulled_from_scan: &pulled_from_scan);
565 six_unlock_read(lock: &b->c.lock);
566
567 if (ret == DROP_THIS_NODE) {
568 bch2_btree_node_hash_remove(&c->btree_cache, b);
569 mutex_lock(&c->btree_cache.lock);
570 list_move(list: &b->list, head: &c->btree_cache.freeable);
571 mutex_unlock(lock: &c->btree_cache.lock);
572
573 r->b = NULL;
574
575 if (!reconstructed_root)
576 goto reconstruct_root;
577
578 bch_err(c, "empty btree root %s", bch2_btree_id_str(i));
579 bch2_btree_root_alloc_fake(c, i, 0);
580 r->alive = false;
581 ret = 0;
582 }
583 }
584fsck_err:
585 bch2_trans_put(trans);
586 return ret;
587}
588
589static int bch2_check_fix_ptrs(struct btree_trans *trans, enum btree_id btree_id,
590 unsigned level, bool is_root,
591 struct bkey_s_c *k)
592{
593 struct bch_fs *c = trans->c;
594 struct bkey_ptrs_c ptrs_c = bch2_bkey_ptrs_c(k: *k);
595 const union bch_extent_entry *entry_c;
596 struct extent_ptr_decoded p = { 0 };
597 bool do_update = false;
598 struct printbuf buf = PRINTBUF;
599 int ret = 0;
600
601 /*
602 * XXX
603 * use check_bucket_ref here
604 */
605 bkey_for_each_ptr_decode(k->k, ptrs_c, p, entry_c) {
606 struct bch_dev *ca = bch_dev_bkey_exists(c, idx: p.ptr.dev);
607 struct bucket *g = PTR_GC_BUCKET(ca, ptr: &p.ptr);
608 enum bch_data_type data_type = bch2_bkey_ptr_data_type(k: *k, p, entry: entry_c);
609
610 if (fsck_err_on(!g->gen_valid,
611 c, ptr_to_missing_alloc_key,
612 "bucket %u:%zu data type %s ptr gen %u missing in alloc btree\n"
613 "while marking %s",
614 p.ptr.dev, PTR_BUCKET_NR(ca, &p.ptr),
615 bch2_data_type_str(ptr_data_type(k->k, &p.ptr)),
616 p.ptr.gen,
617 (printbuf_reset(&buf),
618 bch2_bkey_val_to_text(&buf, c, *k), buf.buf))) {
619 if (!p.ptr.cached) {
620 g->gen_valid = true;
621 g->gen = p.ptr.gen;
622 } else {
623 do_update = true;
624 }
625 }
626
627 if (fsck_err_on(gen_cmp(p.ptr.gen, g->gen) > 0,
628 c, ptr_gen_newer_than_bucket_gen,
629 "bucket %u:%zu data type %s ptr gen in the future: %u > %u\n"
630 "while marking %s",
631 p.ptr.dev, PTR_BUCKET_NR(ca, &p.ptr),
632 bch2_data_type_str(ptr_data_type(k->k, &p.ptr)),
633 p.ptr.gen, g->gen,
634 (printbuf_reset(&buf),
635 bch2_bkey_val_to_text(&buf, c, *k), buf.buf))) {
636 if (!p.ptr.cached) {
637 g->gen_valid = true;
638 g->gen = p.ptr.gen;
639 g->data_type = 0;
640 g->dirty_sectors = 0;
641 g->cached_sectors = 0;
642 set_bit(nr: BCH_FS_need_another_gc, addr: &c->flags);
643 } else {
644 do_update = true;
645 }
646 }
647
648 if (fsck_err_on(gen_cmp(g->gen, p.ptr.gen) > BUCKET_GC_GEN_MAX,
649 c, ptr_gen_newer_than_bucket_gen,
650 "bucket %u:%zu gen %u data type %s: ptr gen %u too stale\n"
651 "while marking %s",
652 p.ptr.dev, PTR_BUCKET_NR(ca, &p.ptr), g->gen,
653 bch2_data_type_str(ptr_data_type(k->k, &p.ptr)),
654 p.ptr.gen,
655 (printbuf_reset(&buf),
656 bch2_bkey_val_to_text(&buf, c, *k), buf.buf)))
657 do_update = true;
658
659 if (fsck_err_on(!p.ptr.cached && gen_cmp(p.ptr.gen, g->gen) < 0,
660 c, stale_dirty_ptr,
661 "bucket %u:%zu data type %s stale dirty ptr: %u < %u\n"
662 "while marking %s",
663 p.ptr.dev, PTR_BUCKET_NR(ca, &p.ptr),
664 bch2_data_type_str(ptr_data_type(k->k, &p.ptr)),
665 p.ptr.gen, g->gen,
666 (printbuf_reset(&buf),
667 bch2_bkey_val_to_text(&buf, c, *k), buf.buf)))
668 do_update = true;
669
670 if (data_type != BCH_DATA_btree && p.ptr.gen != g->gen)
671 continue;
672
673 if (fsck_err_on(bucket_data_type(g->data_type) &&
674 bucket_data_type(g->data_type) !=
675 bucket_data_type(data_type), c,
676 ptr_bucket_data_type_mismatch,
677 "bucket %u:%zu different types of data in same bucket: %s, %s\n"
678 "while marking %s",
679 p.ptr.dev, PTR_BUCKET_NR(ca, &p.ptr),
680 bch2_data_type_str(g->data_type),
681 bch2_data_type_str(data_type),
682 (printbuf_reset(&buf),
683 bch2_bkey_val_to_text(&buf, c, *k), buf.buf))) {
684 if (data_type == BCH_DATA_btree) {
685 g->data_type = data_type;
686 set_bit(nr: BCH_FS_need_another_gc, addr: &c->flags);
687 } else {
688 do_update = true;
689 }
690 }
691
692 if (p.has_ec) {
693 struct gc_stripe *m = genradix_ptr(&c->gc_stripes, p.ec.idx);
694
695 if (fsck_err_on(!m || !m->alive, c,
696 ptr_to_missing_stripe,
697 "pointer to nonexistent stripe %llu\n"
698 "while marking %s",
699 (u64) p.ec.idx,
700 (printbuf_reset(&buf),
701 bch2_bkey_val_to_text(&buf, c, *k), buf.buf)))
702 do_update = true;
703
704 if (fsck_err_on(m && m->alive && !bch2_ptr_matches_stripe_m(m, p), c,
705 ptr_to_incorrect_stripe,
706 "pointer does not match stripe %llu\n"
707 "while marking %s",
708 (u64) p.ec.idx,
709 (printbuf_reset(&buf),
710 bch2_bkey_val_to_text(&buf, c, *k), buf.buf)))
711 do_update = true;
712 }
713 }
714
715 if (do_update) {
716 if (is_root) {
717 bch_err(c, "cannot update btree roots yet");
718 ret = -EINVAL;
719 goto err;
720 }
721
722 struct bkey_i *new = kmalloc(bkey_bytes(k->k), GFP_KERNEL);
723 if (!new) {
724 ret = -BCH_ERR_ENOMEM_gc_repair_key;
725 bch_err_msg(c, ret, "allocating new key");
726 goto err;
727 }
728
729 bkey_reassemble(dst: new, src: *k);
730
731 if (level) {
732 /*
733 * We don't want to drop btree node pointers - if the
734 * btree node isn't there anymore, the read path will
735 * sort it out:
736 */
737 struct bkey_ptrs ptrs = bch2_bkey_ptrs(k: bkey_i_to_s(k: new));
738 bkey_for_each_ptr(ptrs, ptr) {
739 struct bch_dev *ca = bch_dev_bkey_exists(c, idx: ptr->dev);
740 struct bucket *g = PTR_GC_BUCKET(ca, ptr);
741
742 ptr->gen = g->gen;
743 }
744 } else {
745 struct bkey_ptrs ptrs;
746 union bch_extent_entry *entry;
747restart_drop_ptrs:
748 ptrs = bch2_bkey_ptrs(k: bkey_i_to_s(k: new));
749 bkey_for_each_ptr_decode(bkey_i_to_s(new).k, ptrs, p, entry) {
750 struct bch_dev *ca = bch_dev_bkey_exists(c, idx: p.ptr.dev);
751 struct bucket *g = PTR_GC_BUCKET(ca, ptr: &p.ptr);
752 enum bch_data_type data_type = bch2_bkey_ptr_data_type(k: bkey_i_to_s_c(k: new), p, entry);
753
754 if ((p.ptr.cached &&
755 (!g->gen_valid || gen_cmp(a: p.ptr.gen, b: g->gen) > 0)) ||
756 (!p.ptr.cached &&
757 gen_cmp(a: p.ptr.gen, b: g->gen) < 0) ||
758 gen_cmp(a: g->gen, b: p.ptr.gen) > BUCKET_GC_GEN_MAX ||
759 (g->data_type &&
760 g->data_type != data_type)) {
761 bch2_bkey_drop_ptr(bkey_i_to_s(k: new), &entry->ptr);
762 goto restart_drop_ptrs;
763 }
764 }
765again:
766 ptrs = bch2_bkey_ptrs(k: bkey_i_to_s(k: new));
767 bkey_extent_entry_for_each(ptrs, entry) {
768 if (extent_entry_type(e: entry) == BCH_EXTENT_ENTRY_stripe_ptr) {
769 struct gc_stripe *m = genradix_ptr(&c->gc_stripes,
770 entry->stripe_ptr.idx);
771 union bch_extent_entry *next_ptr;
772
773 bkey_extent_entry_for_each_from(ptrs, next_ptr, entry)
774 if (extent_entry_type(e: next_ptr) == BCH_EXTENT_ENTRY_ptr)
775 goto found;
776 next_ptr = NULL;
777found:
778 if (!next_ptr) {
779 bch_err(c, "aieee, found stripe ptr with no data ptr");
780 continue;
781 }
782
783 if (!m || !m->alive ||
784 !__bch2_ptr_matches_stripe(stripe_ptr: &m->ptrs[entry->stripe_ptr.block],
785 data_ptr: &next_ptr->ptr,
786 sectors: m->sectors)) {
787 bch2_bkey_extent_entry_drop(new, entry);
788 goto again;
789 }
790 }
791 }
792 }
793
794 if (level)
795 bch2_btree_node_update_key_early(trans, btree: btree_id, level: level - 1, old: *k, new);
796
797 if (0) {
798 printbuf_reset(buf: &buf);
799 bch2_bkey_val_to_text(&buf, c, *k);
800 bch_info(c, "updated %s", buf.buf);
801
802 printbuf_reset(buf: &buf);
803 bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(k: new));
804 bch_info(c, "new key %s", buf.buf);
805 }
806
807 ret = bch2_journal_key_insert_take(c, btree_id, level, new);
808 if (ret) {
809 kfree(objp: new);
810 goto err;
811 }
812
813 *k = bkey_i_to_s_c(k: new);
814 }
815err:
816fsck_err:
817 printbuf_exit(&buf);
818 return ret;
819}
820
821/* marking of btree keys/nodes: */
822
823static int bch2_gc_mark_key(struct btree_trans *trans, enum btree_id btree_id,
824 unsigned level, bool is_root,
825 struct bkey_s_c *k,
826 bool initial)
827{
828 struct bch_fs *c = trans->c;
829 struct bkey deleted = KEY(0, 0, 0);
830 struct bkey_s_c old = (struct bkey_s_c) { &deleted, NULL };
831 struct printbuf buf = PRINTBUF;
832 int ret = 0;
833
834 deleted.p = k->k->p;
835
836 if (initial) {
837 BUG_ON(bch2_journal_seq_verify &&
838 k->k->version.lo > atomic64_read(&c->journal.seq));
839
840 if (fsck_err_on(k->k->version.lo > atomic64_read(&c->key_version), c,
841 bkey_version_in_future,
842 "key version number higher than recorded: %llu > %llu",
843 k->k->version.lo,
844 atomic64_read(&c->key_version)))
845 atomic64_set(v: &c->key_version, i: k->k->version.lo);
846 }
847
848 ret = bch2_check_fix_ptrs(trans, btree_id, level, is_root, k);
849 if (ret)
850 goto err;
851
852 if (mustfix_fsck_err_on(level && !bch2_dev_btree_bitmap_marked(c, *k),
853 c, btree_bitmap_not_marked,
854 "btree ptr not marked in member info btree allocated bitmap\n %s",
855 (bch2_bkey_val_to_text(&buf, c, *k),
856 buf.buf))) {
857 mutex_lock(&c->sb_lock);
858 bch2_dev_btree_bitmap_mark(c, *k);
859 bch2_write_super(c);
860 mutex_unlock(lock: &c->sb_lock);
861 }
862
863 ret = commit_do(trans, NULL, NULL, 0,
864 bch2_key_trigger(trans, btree_id, level, old,
865 unsafe_bkey_s_c_to_s(*k), BTREE_TRIGGER_GC));
866fsck_err:
867err:
868 printbuf_exit(&buf);
869 bch_err_fn(c, ret);
870 return ret;
871}
872
873static int btree_gc_mark_node(struct btree_trans *trans, struct btree *b, bool initial)
874{
875 struct btree_node_iter iter;
876 struct bkey unpacked;
877 struct bkey_s_c k;
878 int ret = 0;
879
880 ret = bch2_btree_node_check_topology(trans, b);
881 if (ret)
882 return ret;
883
884 if (!btree_node_type_needs_gc(type: btree_node_type(b)))
885 return 0;
886
887 bch2_btree_node_iter_init_from_start(&iter, b);
888
889 while ((k = bch2_btree_node_iter_peek_unpack(&iter, b, &unpacked)).k) {
890 ret = bch2_gc_mark_key(trans, btree_id: b->c.btree_id, level: b->c.level, is_root: false,
891 k: &k, initial);
892 if (ret)
893 return ret;
894
895 bch2_btree_node_iter_advance(&iter, b);
896 }
897
898 return 0;
899}
900
901static int bch2_gc_btree(struct btree_trans *trans, enum btree_id btree_id,
902 bool initial, bool metadata_only)
903{
904 struct bch_fs *c = trans->c;
905 struct btree_iter iter;
906 struct btree *b;
907 unsigned depth = metadata_only ? 1 : 0;
908 int ret = 0;
909
910 gc_pos_set(c, new_pos: gc_pos_btree(id: btree_id, POS_MIN, level: 0));
911
912 __for_each_btree_node(trans, iter, btree_id, POS_MIN,
913 0, depth, BTREE_ITER_PREFETCH, b, ret) {
914 bch2_verify_btree_nr_keys(b);
915
916 gc_pos_set(c, new_pos: gc_pos_btree_node(b));
917
918 ret = btree_gc_mark_node(trans, b, initial);
919 if (ret)
920 break;
921 }
922 bch2_trans_iter_exit(trans, &iter);
923
924 if (ret)
925 return ret;
926
927 mutex_lock(&c->btree_root_lock);
928 b = bch2_btree_id_root(c, id: btree_id)->b;
929 if (!btree_node_fake(b)) {
930 struct bkey_s_c k = bkey_i_to_s_c(k: &b->key);
931
932 ret = bch2_gc_mark_key(trans, btree_id: b->c.btree_id, level: b->c.level + 1,
933 is_root: true, k: &k, initial);
934 }
935 gc_pos_set(c, new_pos: gc_pos_btree_root(id: b->c.btree_id));
936 mutex_unlock(lock: &c->btree_root_lock);
937
938 return ret;
939}
940
941static int bch2_gc_btree_init_recurse(struct btree_trans *trans, struct btree *b,
942 unsigned target_depth)
943{
944 struct bch_fs *c = trans->c;
945 struct btree_and_journal_iter iter;
946 struct bkey_s_c k;
947 struct bkey_buf cur;
948 struct printbuf buf = PRINTBUF;
949 int ret = 0;
950
951 ret = bch2_btree_node_check_topology(trans, b);
952 if (ret)
953 return ret;
954
955 bch2_btree_and_journal_iter_init_node_iter(trans, &iter, b);
956 bch2_bkey_buf_init(s: &cur);
957
958 while ((k = bch2_btree_and_journal_iter_peek(&iter)).k) {
959 BUG_ON(bpos_lt(k.k->p, b->data->min_key));
960 BUG_ON(bpos_gt(k.k->p, b->data->max_key));
961
962 ret = bch2_gc_mark_key(trans, btree_id: b->c.btree_id, level: b->c.level,
963 is_root: false, k: &k, initial: true);
964 if (ret)
965 goto fsck_err;
966
967 bch2_btree_and_journal_iter_advance(&iter);
968 }
969
970 if (b->c.level > target_depth) {
971 bch2_btree_and_journal_iter_exit(&iter);
972 bch2_btree_and_journal_iter_init_node_iter(trans, &iter, b);
973 iter.prefetch = true;
974
975 while ((k = bch2_btree_and_journal_iter_peek(&iter)).k) {
976 struct btree *child;
977
978 bch2_bkey_buf_reassemble(s: &cur, c, k);
979 bch2_btree_and_journal_iter_advance(&iter);
980
981 child = bch2_btree_node_get_noiter(trans, cur.k,
982 b->c.btree_id, b->c.level - 1,
983 false);
984 ret = PTR_ERR_OR_ZERO(ptr: child);
985
986 if (bch2_err_matches(ret, EIO)) {
987 bch2_topology_error(c);
988
989 if (__fsck_err(c,
990 FSCK_CAN_FIX|
991 FSCK_CAN_IGNORE|
992 FSCK_NO_RATELIMIT,
993 btree_node_read_error,
994 "Unreadable btree node at btree %s level %u:\n"
995 " %s",
996 bch2_btree_id_str(b->c.btree_id),
997 b->c.level - 1,
998 (printbuf_reset(&buf),
999 bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(cur.k)), buf.buf)) &&
1000 should_restart_for_topology_repair(c)) {
1001 bch_info(c, "Halting mark and sweep to start topology repair pass");
1002 ret = bch2_run_explicit_recovery_pass(c, BCH_RECOVERY_PASS_check_topology);
1003 goto fsck_err;
1004 } else {
1005 /* Continue marking when opted to not
1006 * fix the error: */
1007 ret = 0;
1008 set_bit(nr: BCH_FS_initial_gc_unfixed, addr: &c->flags);
1009 continue;
1010 }
1011 } else if (ret) {
1012 bch_err_msg(c, ret, "getting btree node");
1013 break;
1014 }
1015
1016 ret = bch2_gc_btree_init_recurse(trans, b: child,
1017 target_depth);
1018 six_unlock_read(lock: &child->c.lock);
1019
1020 if (ret)
1021 break;
1022 }
1023 }
1024fsck_err:
1025 bch2_bkey_buf_exit(s: &cur, c);
1026 bch2_btree_and_journal_iter_exit(&iter);
1027 printbuf_exit(&buf);
1028 return ret;
1029}
1030
1031static int bch2_gc_btree_init(struct btree_trans *trans,
1032 enum btree_id btree_id,
1033 bool metadata_only)
1034{
1035 struct bch_fs *c = trans->c;
1036 struct btree *b;
1037 unsigned target_depth = metadata_only ? 1 : 0;
1038 struct printbuf buf = PRINTBUF;
1039 int ret = 0;
1040
1041 b = bch2_btree_id_root(c, id: btree_id)->b;
1042
1043 six_lock_read(lock: &b->c.lock, NULL, NULL);
1044 printbuf_reset(buf: &buf);
1045 bch2_bpos_to_text(&buf, b->data->min_key);
1046 if (mustfix_fsck_err_on(!bpos_eq(b->data->min_key, POS_MIN), c,
1047 btree_root_bad_min_key,
1048 "btree root with incorrect min_key: %s", buf.buf)) {
1049 bch_err(c, "repair unimplemented");
1050 ret = -BCH_ERR_fsck_repair_unimplemented;
1051 goto fsck_err;
1052 }
1053
1054 printbuf_reset(buf: &buf);
1055 bch2_bpos_to_text(&buf, b->data->max_key);
1056 if (mustfix_fsck_err_on(!bpos_eq(b->data->max_key, SPOS_MAX), c,
1057 btree_root_bad_max_key,
1058 "btree root with incorrect max_key: %s", buf.buf)) {
1059 bch_err(c, "repair unimplemented");
1060 ret = -BCH_ERR_fsck_repair_unimplemented;
1061 goto fsck_err;
1062 }
1063
1064 if (b->c.level >= target_depth)
1065 ret = bch2_gc_btree_init_recurse(trans, b, target_depth);
1066
1067 if (!ret) {
1068 struct bkey_s_c k = bkey_i_to_s_c(k: &b->key);
1069
1070 ret = bch2_gc_mark_key(trans, btree_id: b->c.btree_id, level: b->c.level + 1, is_root: true,
1071 k: &k, initial: true);
1072 }
1073fsck_err:
1074 six_unlock_read(lock: &b->c.lock);
1075
1076 bch_err_fn(c, ret);
1077 printbuf_exit(&buf);
1078 return ret;
1079}
1080
1081static inline int btree_id_gc_phase_cmp(enum btree_id l, enum btree_id r)
1082{
1083 return (int) btree_id_to_gc_phase(id: l) -
1084 (int) btree_id_to_gc_phase(id: r);
1085}
1086
1087static int bch2_gc_btrees(struct bch_fs *c, bool initial, bool metadata_only)
1088{
1089 struct btree_trans *trans = bch2_trans_get(c);
1090 enum btree_id ids[BTREE_ID_NR];
1091 unsigned i;
1092 int ret = 0;
1093
1094 for (i = 0; i < BTREE_ID_NR; i++)
1095 ids[i] = i;
1096 bubble_sort(ids, BTREE_ID_NR, btree_id_gc_phase_cmp);
1097
1098 for (i = 0; i < BTREE_ID_NR && !ret; i++)
1099 ret = initial
1100 ? bch2_gc_btree_init(trans, btree_id: ids[i], metadata_only)
1101 : bch2_gc_btree(trans, btree_id: ids[i], initial, metadata_only);
1102
1103 for (i = BTREE_ID_NR; i < btree_id_nr_alive(c) && !ret; i++) {
1104 if (!bch2_btree_id_root(c, id: i)->alive)
1105 continue;
1106
1107 ret = initial
1108 ? bch2_gc_btree_init(trans, btree_id: i, metadata_only)
1109 : bch2_gc_btree(trans, btree_id: i, initial, metadata_only);
1110 }
1111
1112 bch2_trans_put(trans);
1113 bch_err_fn(c, ret);
1114 return ret;
1115}
1116
1117static void mark_metadata_sectors(struct bch_fs *c, struct bch_dev *ca,
1118 u64 start, u64 end,
1119 enum bch_data_type type,
1120 unsigned flags)
1121{
1122 u64 b = sector_to_bucket(ca, s: start);
1123
1124 do {
1125 unsigned sectors =
1126 min_t(u64, bucket_to_sector(ca, b + 1), end) - start;
1127
1128 bch2_mark_metadata_bucket(c, ca, b, type, sectors,
1129 gc_phase(phase: GC_PHASE_SB), flags);
1130 b++;
1131 start += sectors;
1132 } while (start < end);
1133}
1134
1135static void bch2_mark_dev_superblock(struct bch_fs *c, struct bch_dev *ca,
1136 unsigned flags)
1137{
1138 struct bch_sb_layout *layout = &ca->disk_sb.sb->layout;
1139 unsigned i;
1140 u64 b;
1141
1142 for (i = 0; i < layout->nr_superblocks; i++) {
1143 u64 offset = le64_to_cpu(layout->sb_offset[i]);
1144
1145 if (offset == BCH_SB_SECTOR)
1146 mark_metadata_sectors(c, ca, start: 0, BCH_SB_SECTOR,
1147 type: BCH_DATA_sb, flags);
1148
1149 mark_metadata_sectors(c, ca, start: offset,
1150 end: offset + (1 << layout->sb_max_size_bits),
1151 type: BCH_DATA_sb, flags);
1152 }
1153
1154 for (i = 0; i < ca->journal.nr; i++) {
1155 b = ca->journal.buckets[i];
1156 bch2_mark_metadata_bucket(c, ca, b, BCH_DATA_journal,
1157 ca->mi.bucket_size,
1158 gc_phase(phase: GC_PHASE_SB), flags);
1159 }
1160}
1161
1162static void bch2_mark_superblocks(struct bch_fs *c)
1163{
1164 mutex_lock(&c->sb_lock);
1165 gc_pos_set(c, new_pos: gc_phase(phase: GC_PHASE_SB));
1166
1167 for_each_online_member(c, ca)
1168 bch2_mark_dev_superblock(c, ca, BTREE_TRIGGER_GC);
1169 mutex_unlock(lock: &c->sb_lock);
1170}
1171
1172#if 0
1173/* Also see bch2_pending_btree_node_free_insert_done() */
1174static void bch2_mark_pending_btree_node_frees(struct bch_fs *c)
1175{
1176 struct btree_update *as;
1177 struct pending_btree_node_free *d;
1178
1179 mutex_lock(&c->btree_interior_update_lock);
1180 gc_pos_set(c, gc_phase(GC_PHASE_PENDING_DELETE));
1181
1182 for_each_pending_btree_node_free(c, as, d)
1183 if (d->index_update_done)
1184 bch2_mark_key(c, bkey_i_to_s_c(&d->key), BTREE_TRIGGER_GC);
1185
1186 mutex_unlock(&c->btree_interior_update_lock);
1187}
1188#endif
1189
1190static void bch2_gc_free(struct bch_fs *c)
1191{
1192 genradix_free(&c->reflink_gc_table);
1193 genradix_free(&c->gc_stripes);
1194
1195 for_each_member_device(c, ca) {
1196 kvfree(rcu_dereference_protected(ca->buckets_gc, 1));
1197 ca->buckets_gc = NULL;
1198
1199 free_percpu(pdata: ca->usage_gc);
1200 ca->usage_gc = NULL;
1201 }
1202
1203 free_percpu(pdata: c->usage_gc);
1204 c->usage_gc = NULL;
1205}
1206
1207static int bch2_gc_done(struct bch_fs *c,
1208 bool initial, bool metadata_only)
1209{
1210 struct bch_dev *ca = NULL;
1211 struct printbuf buf = PRINTBUF;
1212 bool verify = !metadata_only &&
1213 !c->opts.reconstruct_alloc &&
1214 (!initial || (c->sb.compat & (1ULL << BCH_COMPAT_alloc_info)));
1215 unsigned i;
1216 int ret = 0;
1217
1218 percpu_down_write(&c->mark_lock);
1219
1220#define copy_field(_err, _f, _msg, ...) \
1221 if (dst->_f != src->_f && \
1222 (!verify || \
1223 fsck_err(c, _err, _msg ": got %llu, should be %llu" \
1224 , ##__VA_ARGS__, dst->_f, src->_f))) \
1225 dst->_f = src->_f
1226#define copy_dev_field(_err, _f, _msg, ...) \
1227 copy_field(_err, _f, "dev %u has wrong " _msg, ca->dev_idx, ##__VA_ARGS__)
1228#define copy_fs_field(_err, _f, _msg, ...) \
1229 copy_field(_err, _f, "fs has wrong " _msg, ##__VA_ARGS__)
1230
1231 for (i = 0; i < ARRAY_SIZE(c->usage); i++)
1232 bch2_fs_usage_acc_to_base(c, i);
1233
1234 __for_each_member_device(c, ca) {
1235 struct bch_dev_usage *dst = ca->usage_base;
1236 struct bch_dev_usage *src = (void *)
1237 bch2_acc_percpu_u64s((u64 __percpu *) ca->usage_gc,
1238 dev_usage_u64s());
1239
1240 for (i = 0; i < BCH_DATA_NR; i++) {
1241 copy_dev_field(dev_usage_buckets_wrong,
1242 d[i].buckets, "%s buckets", bch2_data_type_str(i));
1243 copy_dev_field(dev_usage_sectors_wrong,
1244 d[i].sectors, "%s sectors", bch2_data_type_str(i));
1245 copy_dev_field(dev_usage_fragmented_wrong,
1246 d[i].fragmented, "%s fragmented", bch2_data_type_str(i));
1247 }
1248 }
1249
1250 {
1251 unsigned nr = fs_usage_u64s(c);
1252 struct bch_fs_usage *dst = c->usage_base;
1253 struct bch_fs_usage *src = (void *)
1254 bch2_acc_percpu_u64s((u64 __percpu *) c->usage_gc, nr);
1255
1256 copy_fs_field(fs_usage_hidden_wrong,
1257 b.hidden, "hidden");
1258 copy_fs_field(fs_usage_btree_wrong,
1259 b.btree, "btree");
1260
1261 if (!metadata_only) {
1262 copy_fs_field(fs_usage_data_wrong,
1263 b.data, "data");
1264 copy_fs_field(fs_usage_cached_wrong,
1265 b.cached, "cached");
1266 copy_fs_field(fs_usage_reserved_wrong,
1267 b.reserved, "reserved");
1268 copy_fs_field(fs_usage_nr_inodes_wrong,
1269 b.nr_inodes,"nr_inodes");
1270
1271 for (i = 0; i < BCH_REPLICAS_MAX; i++)
1272 copy_fs_field(fs_usage_persistent_reserved_wrong,
1273 persistent_reserved[i],
1274 "persistent_reserved[%i]", i);
1275 }
1276
1277 for (i = 0; i < c->replicas.nr; i++) {
1278 struct bch_replicas_entry_v1 *e =
1279 cpu_replicas_entry(r: &c->replicas, i);
1280
1281 if (metadata_only &&
1282 (e->data_type == BCH_DATA_user ||
1283 e->data_type == BCH_DATA_cached))
1284 continue;
1285
1286 printbuf_reset(buf: &buf);
1287 bch2_replicas_entry_to_text(&buf, e);
1288
1289 copy_fs_field(fs_usage_replicas_wrong,
1290 replicas[i], "%s", buf.buf);
1291 }
1292 }
1293
1294#undef copy_fs_field
1295#undef copy_dev_field
1296#undef copy_stripe_field
1297#undef copy_field
1298fsck_err:
1299 if (ca)
1300 percpu_ref_put(ref: &ca->ref);
1301 bch_err_fn(c, ret);
1302
1303 percpu_up_write(&c->mark_lock);
1304 printbuf_exit(&buf);
1305 return ret;
1306}
1307
1308static int bch2_gc_start(struct bch_fs *c)
1309{
1310 BUG_ON(c->usage_gc);
1311
1312 c->usage_gc = __alloc_percpu_gfp(size: fs_usage_u64s(c) * sizeof(u64),
1313 align: sizeof(u64), GFP_KERNEL);
1314 if (!c->usage_gc) {
1315 bch_err(c, "error allocating c->usage_gc");
1316 return -BCH_ERR_ENOMEM_gc_start;
1317 }
1318
1319 for_each_member_device(c, ca) {
1320 BUG_ON(ca->usage_gc);
1321
1322 ca->usage_gc = alloc_percpu(struct bch_dev_usage);
1323 if (!ca->usage_gc) {
1324 bch_err(c, "error allocating ca->usage_gc");
1325 percpu_ref_put(ref: &ca->ref);
1326 return -BCH_ERR_ENOMEM_gc_start;
1327 }
1328
1329 this_cpu_write(ca->usage_gc->d[BCH_DATA_free].buckets,
1330 ca->mi.nbuckets - ca->mi.first_bucket);
1331 }
1332
1333 return 0;
1334}
1335
1336static int bch2_gc_reset(struct bch_fs *c)
1337{
1338 for_each_member_device(c, ca) {
1339 free_percpu(pdata: ca->usage_gc);
1340 ca->usage_gc = NULL;
1341 }
1342
1343 free_percpu(pdata: c->usage_gc);
1344 c->usage_gc = NULL;
1345
1346 return bch2_gc_start(c);
1347}
1348
1349/* returns true if not equal */
1350static inline bool bch2_alloc_v4_cmp(struct bch_alloc_v4 l,
1351 struct bch_alloc_v4 r)
1352{
1353 return l.gen != r.gen ||
1354 l.oldest_gen != r.oldest_gen ||
1355 l.data_type != r.data_type ||
1356 l.dirty_sectors != r.dirty_sectors ||
1357 l.cached_sectors != r.cached_sectors ||
1358 l.stripe_redundancy != r.stripe_redundancy ||
1359 l.stripe != r.stripe;
1360}
1361
1362static int bch2_alloc_write_key(struct btree_trans *trans,
1363 struct btree_iter *iter,
1364 struct bkey_s_c k,
1365 bool metadata_only)
1366{
1367 struct bch_fs *c = trans->c;
1368 struct bch_dev *ca = bch_dev_bkey_exists(c, idx: iter->pos.inode);
1369 struct bucket old_gc, gc, *b;
1370 struct bkey_i_alloc_v4 *a;
1371 struct bch_alloc_v4 old_convert, new;
1372 const struct bch_alloc_v4 *old;
1373 int ret;
1374
1375 old = bch2_alloc_to_v4(k, convert: &old_convert);
1376 new = *old;
1377
1378 percpu_down_read(sem: &c->mark_lock);
1379 b = gc_bucket(ca, b: iter->pos.offset);
1380 old_gc = *b;
1381
1382 if ((old->data_type == BCH_DATA_sb ||
1383 old->data_type == BCH_DATA_journal) &&
1384 !bch2_dev_is_online(ca)) {
1385 b->data_type = old->data_type;
1386 b->dirty_sectors = old->dirty_sectors;
1387 }
1388
1389 /*
1390 * b->data_type doesn't yet include need_discard & need_gc_gen states -
1391 * fix that here:
1392 */
1393 b->data_type = __alloc_data_type(dirty_sectors: b->dirty_sectors,
1394 cached_sectors: b->cached_sectors,
1395 stripe: b->stripe,
1396 a: *old,
1397 data_type: b->data_type);
1398 gc = *b;
1399
1400 if (gc.data_type != old_gc.data_type ||
1401 gc.dirty_sectors != old_gc.dirty_sectors)
1402 bch2_dev_usage_update_m(c, ca, &old_gc, &gc);
1403 percpu_up_read(sem: &c->mark_lock);
1404
1405 if (metadata_only &&
1406 gc.data_type != BCH_DATA_sb &&
1407 gc.data_type != BCH_DATA_journal &&
1408 gc.data_type != BCH_DATA_btree)
1409 return 0;
1410
1411 if (gen_after(a: old->gen, b: gc.gen))
1412 return 0;
1413
1414 if (fsck_err_on(new.data_type != gc.data_type, c,
1415 alloc_key_data_type_wrong,
1416 "bucket %llu:%llu gen %u has wrong data_type"
1417 ": got %s, should be %s",
1418 iter->pos.inode, iter->pos.offset,
1419 gc.gen,
1420 bch2_data_type_str(new.data_type),
1421 bch2_data_type_str(gc.data_type)))
1422 new.data_type = gc.data_type;
1423
1424#define copy_bucket_field(_errtype, _f) \
1425 if (fsck_err_on(new._f != gc._f, c, _errtype, \
1426 "bucket %llu:%llu gen %u data type %s has wrong " #_f \
1427 ": got %u, should be %u", \
1428 iter->pos.inode, iter->pos.offset, \
1429 gc.gen, \
1430 bch2_data_type_str(gc.data_type), \
1431 new._f, gc._f)) \
1432 new._f = gc._f; \
1433
1434 copy_bucket_field(alloc_key_gen_wrong,
1435 gen);
1436 copy_bucket_field(alloc_key_dirty_sectors_wrong,
1437 dirty_sectors);
1438 copy_bucket_field(alloc_key_cached_sectors_wrong,
1439 cached_sectors);
1440 copy_bucket_field(alloc_key_stripe_wrong,
1441 stripe);
1442 copy_bucket_field(alloc_key_stripe_redundancy_wrong,
1443 stripe_redundancy);
1444#undef copy_bucket_field
1445
1446 if (!bch2_alloc_v4_cmp(l: *old, r: new))
1447 return 0;
1448
1449 a = bch2_alloc_to_v4_mut(trans, k);
1450 ret = PTR_ERR_OR_ZERO(ptr: a);
1451 if (ret)
1452 return ret;
1453
1454 a->v = new;
1455
1456 /*
1457 * The trigger normally makes sure this is set, but we're not running
1458 * triggers:
1459 */
1460 if (a->v.data_type == BCH_DATA_cached && !a->v.io_time[READ])
1461 a->v.io_time[READ] = max_t(u64, 1, atomic64_read(&c->io_clock[READ].now));
1462
1463 ret = bch2_trans_update(trans, iter, &a->k_i, BTREE_TRIGGER_NORUN);
1464fsck_err:
1465 return ret;
1466}
1467
1468static int bch2_gc_alloc_done(struct bch_fs *c, bool metadata_only)
1469{
1470 int ret = 0;
1471
1472 for_each_member_device(c, ca) {
1473 ret = bch2_trans_run(c,
1474 for_each_btree_key_upto_commit(trans, iter, BTREE_ID_alloc,
1475 POS(ca->dev_idx, ca->mi.first_bucket),
1476 POS(ca->dev_idx, ca->mi.nbuckets - 1),
1477 BTREE_ITER_SLOTS|BTREE_ITER_PREFETCH, k,
1478 NULL, NULL, BCH_TRANS_COMMIT_lazy_rw,
1479 bch2_alloc_write_key(trans, &iter, k, metadata_only)));
1480 if (ret) {
1481 percpu_ref_put(ref: &ca->ref);
1482 break;
1483 }
1484 }
1485
1486 bch_err_fn(c, ret);
1487 return ret;
1488}
1489
1490static int bch2_gc_alloc_start(struct bch_fs *c, bool metadata_only)
1491{
1492 for_each_member_device(c, ca) {
1493 struct bucket_array *buckets = kvmalloc(size: sizeof(struct bucket_array) +
1494 ca->mi.nbuckets * sizeof(struct bucket),
1495 GFP_KERNEL|__GFP_ZERO);
1496 if (!buckets) {
1497 percpu_ref_put(ref: &ca->ref);
1498 bch_err(c, "error allocating ca->buckets[gc]");
1499 return -BCH_ERR_ENOMEM_gc_alloc_start;
1500 }
1501
1502 buckets->first_bucket = ca->mi.first_bucket;
1503 buckets->nbuckets = ca->mi.nbuckets;
1504 rcu_assign_pointer(ca->buckets_gc, buckets);
1505 }
1506
1507 int ret = bch2_trans_run(c,
1508 for_each_btree_key(trans, iter, BTREE_ID_alloc, POS_MIN,
1509 BTREE_ITER_PREFETCH, k, ({
1510 struct bch_dev *ca = bch_dev_bkey_exists(c, k.k->p.inode);
1511 struct bucket *g = gc_bucket(ca, k.k->p.offset);
1512
1513 struct bch_alloc_v4 a_convert;
1514 const struct bch_alloc_v4 *a = bch2_alloc_to_v4(k, &a_convert);
1515
1516 g->gen_valid = 1;
1517 g->gen = a->gen;
1518
1519 if (metadata_only &&
1520 (a->data_type == BCH_DATA_user ||
1521 a->data_type == BCH_DATA_cached ||
1522 a->data_type == BCH_DATA_parity)) {
1523 g->data_type = a->data_type;
1524 g->dirty_sectors = a->dirty_sectors;
1525 g->cached_sectors = a->cached_sectors;
1526 g->stripe = a->stripe;
1527 g->stripe_redundancy = a->stripe_redundancy;
1528 }
1529
1530 0;
1531 })));
1532 bch_err_fn(c, ret);
1533 return ret;
1534}
1535
1536static void bch2_gc_alloc_reset(struct bch_fs *c, bool metadata_only)
1537{
1538 for_each_member_device(c, ca) {
1539 struct bucket_array *buckets = gc_bucket_array(ca);
1540 struct bucket *g;
1541
1542 for_each_bucket(g, buckets) {
1543 if (metadata_only &&
1544 (g->data_type == BCH_DATA_user ||
1545 g->data_type == BCH_DATA_cached ||
1546 g->data_type == BCH_DATA_parity))
1547 continue;
1548 g->data_type = 0;
1549 g->dirty_sectors = 0;
1550 g->cached_sectors = 0;
1551 }
1552 }
1553}
1554
1555static int bch2_gc_write_reflink_key(struct btree_trans *trans,
1556 struct btree_iter *iter,
1557 struct bkey_s_c k,
1558 size_t *idx)
1559{
1560 struct bch_fs *c = trans->c;
1561 const __le64 *refcount = bkey_refcount_c(k);
1562 struct printbuf buf = PRINTBUF;
1563 struct reflink_gc *r;
1564 int ret = 0;
1565
1566 if (!refcount)
1567 return 0;
1568
1569 while ((r = genradix_ptr(&c->reflink_gc_table, *idx)) &&
1570 r->offset < k.k->p.offset)
1571 ++*idx;
1572
1573 if (!r ||
1574 r->offset != k.k->p.offset ||
1575 r->size != k.k->size) {
1576 bch_err(c, "unexpected inconsistency walking reflink table at gc finish");
1577 return -EINVAL;
1578 }
1579
1580 if (fsck_err_on(r->refcount != le64_to_cpu(*refcount), c,
1581 reflink_v_refcount_wrong,
1582 "reflink key has wrong refcount:\n"
1583 " %s\n"
1584 " should be %u",
1585 (bch2_bkey_val_to_text(&buf, c, k), buf.buf),
1586 r->refcount)) {
1587 struct bkey_i *new = bch2_bkey_make_mut_noupdate(trans, k);
1588 ret = PTR_ERR_OR_ZERO(ptr: new);
1589 if (ret)
1590 goto out;
1591
1592 if (!r->refcount)
1593 new->k.type = KEY_TYPE_deleted;
1594 else
1595 *bkey_refcount(k: bkey_i_to_s(k: new)) = cpu_to_le64(r->refcount);
1596 ret = bch2_trans_update(trans, iter, new, 0);
1597 }
1598out:
1599fsck_err:
1600 printbuf_exit(&buf);
1601 return ret;
1602}
1603
1604static int bch2_gc_reflink_done(struct bch_fs *c, bool metadata_only)
1605{
1606 size_t idx = 0;
1607
1608 if (metadata_only)
1609 return 0;
1610
1611 int ret = bch2_trans_run(c,
1612 for_each_btree_key_commit(trans, iter,
1613 BTREE_ID_reflink, POS_MIN,
1614 BTREE_ITER_PREFETCH, k,
1615 NULL, NULL, BCH_TRANS_COMMIT_no_enospc,
1616 bch2_gc_write_reflink_key(trans, &iter, k, &idx)));
1617 c->reflink_gc_nr = 0;
1618 return ret;
1619}
1620
1621static int bch2_gc_reflink_start(struct bch_fs *c,
1622 bool metadata_only)
1623{
1624
1625 if (metadata_only)
1626 return 0;
1627
1628 c->reflink_gc_nr = 0;
1629
1630 int ret = bch2_trans_run(c,
1631 for_each_btree_key(trans, iter, BTREE_ID_reflink, POS_MIN,
1632 BTREE_ITER_PREFETCH, k, ({
1633 const __le64 *refcount = bkey_refcount_c(k);
1634
1635 if (!refcount)
1636 continue;
1637
1638 struct reflink_gc *r = genradix_ptr_alloc(&c->reflink_gc_table,
1639 c->reflink_gc_nr++, GFP_KERNEL);
1640 if (!r) {
1641 ret = -BCH_ERR_ENOMEM_gc_reflink_start;
1642 break;
1643 }
1644
1645 r->offset = k.k->p.offset;
1646 r->size = k.k->size;
1647 r->refcount = 0;
1648 0;
1649 })));
1650
1651 bch_err_fn(c, ret);
1652 return ret;
1653}
1654
1655static void bch2_gc_reflink_reset(struct bch_fs *c, bool metadata_only)
1656{
1657 struct genradix_iter iter;
1658 struct reflink_gc *r;
1659
1660 genradix_for_each(&c->reflink_gc_table, iter, r)
1661 r->refcount = 0;
1662}
1663
1664static int bch2_gc_write_stripes_key(struct btree_trans *trans,
1665 struct btree_iter *iter,
1666 struct bkey_s_c k)
1667{
1668 struct bch_fs *c = trans->c;
1669 struct printbuf buf = PRINTBUF;
1670 const struct bch_stripe *s;
1671 struct gc_stripe *m;
1672 bool bad = false;
1673 unsigned i;
1674 int ret = 0;
1675
1676 if (k.k->type != KEY_TYPE_stripe)
1677 return 0;
1678
1679 s = bkey_s_c_to_stripe(k).v;
1680 m = genradix_ptr(&c->gc_stripes, k.k->p.offset);
1681
1682 for (i = 0; i < s->nr_blocks; i++) {
1683 u32 old = stripe_blockcount_get(s, idx: i);
1684 u32 new = (m ? m->block_sectors[i] : 0);
1685
1686 if (old != new) {
1687 prt_printf(&buf, "stripe block %u has wrong sector count: got %u, should be %u\n",
1688 i, old, new);
1689 bad = true;
1690 }
1691 }
1692
1693 if (bad)
1694 bch2_bkey_val_to_text(&buf, c, k);
1695
1696 if (fsck_err_on(bad, c, stripe_sector_count_wrong,
1697 "%s", buf.buf)) {
1698 struct bkey_i_stripe *new;
1699
1700 new = bch2_trans_kmalloc(trans, bkey_bytes(k.k));
1701 ret = PTR_ERR_OR_ZERO(ptr: new);
1702 if (ret)
1703 return ret;
1704
1705 bkey_reassemble(dst: &new->k_i, src: k);
1706
1707 for (i = 0; i < new->v.nr_blocks; i++)
1708 stripe_blockcount_set(s: &new->v, idx: i, v: m ? m->block_sectors[i] : 0);
1709
1710 ret = bch2_trans_update(trans, iter, &new->k_i, 0);
1711 }
1712fsck_err:
1713 printbuf_exit(&buf);
1714 return ret;
1715}
1716
1717static int bch2_gc_stripes_done(struct bch_fs *c, bool metadata_only)
1718{
1719 if (metadata_only)
1720 return 0;
1721
1722 return bch2_trans_run(c,
1723 for_each_btree_key_commit(trans, iter,
1724 BTREE_ID_stripes, POS_MIN,
1725 BTREE_ITER_PREFETCH, k,
1726 NULL, NULL, BCH_TRANS_COMMIT_no_enospc,
1727 bch2_gc_write_stripes_key(trans, &iter, k)));
1728}
1729
1730static void bch2_gc_stripes_reset(struct bch_fs *c, bool metadata_only)
1731{
1732 genradix_free(&c->gc_stripes);
1733}
1734
1735/**
1736 * bch2_gc - walk _all_ references to buckets, and recompute them:
1737 *
1738 * @c: filesystem object
1739 * @initial: are we in recovery?
1740 * @metadata_only: are we just checking metadata references, or everything?
1741 *
1742 * Returns: 0 on success, or standard errcode on failure
1743 *
1744 * Order matters here:
1745 * - Concurrent GC relies on the fact that we have a total ordering for
1746 * everything that GC walks - see gc_will_visit_node(),
1747 * gc_will_visit_root()
1748 *
1749 * - also, references move around in the course of index updates and
1750 * various other crap: everything needs to agree on the ordering
1751 * references are allowed to move around in - e.g., we're allowed to
1752 * start with a reference owned by an open_bucket (the allocator) and
1753 * move it to the btree, but not the reverse.
1754 *
1755 * This is necessary to ensure that gc doesn't miss references that
1756 * move around - if references move backwards in the ordering GC
1757 * uses, GC could skip past them
1758 */
1759int bch2_gc(struct bch_fs *c, bool initial, bool metadata_only)
1760{
1761 unsigned iter = 0;
1762 int ret;
1763
1764 lockdep_assert_held(&c->state_lock);
1765
1766 down_write(sem: &c->gc_lock);
1767
1768 bch2_btree_interior_updates_flush(c);
1769
1770 ret = bch2_gc_start(c) ?:
1771 bch2_gc_alloc_start(c, metadata_only) ?:
1772 bch2_gc_reflink_start(c, metadata_only);
1773 if (ret)
1774 goto out;
1775again:
1776 gc_pos_set(c, new_pos: gc_phase(phase: GC_PHASE_START));
1777
1778 bch2_mark_superblocks(c);
1779
1780 ret = bch2_gc_btrees(c, initial, metadata_only);
1781
1782 if (ret)
1783 goto out;
1784
1785#if 0
1786 bch2_mark_pending_btree_node_frees(c);
1787#endif
1788 c->gc_count++;
1789
1790 if (test_bit(BCH_FS_need_another_gc, &c->flags) ||
1791 (!iter && bch2_test_restart_gc)) {
1792 if (iter++ > 2) {
1793 bch_info(c, "Unable to fix bucket gens, looping");
1794 ret = -EINVAL;
1795 goto out;
1796 }
1797
1798 /*
1799 * XXX: make sure gens we fixed got saved
1800 */
1801 bch_info(c, "Second GC pass needed, restarting:");
1802 clear_bit(nr: BCH_FS_need_another_gc, addr: &c->flags);
1803 __gc_pos_set(c, new_pos: gc_phase(phase: GC_PHASE_NOT_RUNNING));
1804
1805 bch2_gc_stripes_reset(c, metadata_only);
1806 bch2_gc_alloc_reset(c, metadata_only);
1807 bch2_gc_reflink_reset(c, metadata_only);
1808 ret = bch2_gc_reset(c);
1809 if (ret)
1810 goto out;
1811
1812 /* flush fsck errors, reset counters */
1813 bch2_flush_fsck_errs(c);
1814 goto again;
1815 }
1816out:
1817 if (!ret) {
1818 bch2_journal_block(&c->journal);
1819
1820 ret = bch2_gc_alloc_done(c, metadata_only) ?:
1821 bch2_gc_done(c, initial, metadata_only) ?:
1822 bch2_gc_stripes_done(c, metadata_only) ?:
1823 bch2_gc_reflink_done(c, metadata_only);
1824
1825 bch2_journal_unblock(&c->journal);
1826 }
1827
1828 percpu_down_write(&c->mark_lock);
1829 /* Indicates that gc is no longer in progress: */
1830 __gc_pos_set(c, new_pos: gc_phase(phase: GC_PHASE_NOT_RUNNING));
1831
1832 bch2_gc_free(c);
1833 percpu_up_write(&c->mark_lock);
1834
1835 up_write(sem: &c->gc_lock);
1836
1837 /*
1838 * At startup, allocations can happen directly instead of via the
1839 * allocator thread - issue wakeup in case they blocked on gc_lock:
1840 */
1841 closure_wake_up(list: &c->freelist_wait);
1842 bch_err_fn(c, ret);
1843 return ret;
1844}
1845
1846static int gc_btree_gens_key(struct btree_trans *trans,
1847 struct btree_iter *iter,
1848 struct bkey_s_c k)
1849{
1850 struct bch_fs *c = trans->c;
1851 struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
1852 struct bkey_i *u;
1853 int ret;
1854
1855 percpu_down_read(sem: &c->mark_lock);
1856 bkey_for_each_ptr(ptrs, ptr) {
1857 struct bch_dev *ca = bch_dev_bkey_exists(c, idx: ptr->dev);
1858
1859 if (ptr_stale(ca, ptr) > 16) {
1860 percpu_up_read(sem: &c->mark_lock);
1861 goto update;
1862 }
1863 }
1864
1865 bkey_for_each_ptr(ptrs, ptr) {
1866 struct bch_dev *ca = bch_dev_bkey_exists(c, idx: ptr->dev);
1867 u8 *gen = &ca->oldest_gen[PTR_BUCKET_NR(ca, ptr)];
1868
1869 if (gen_after(a: *gen, b: ptr->gen))
1870 *gen = ptr->gen;
1871 }
1872 percpu_up_read(sem: &c->mark_lock);
1873 return 0;
1874update:
1875 u = bch2_bkey_make_mut(trans, iter, k: &k, flags: 0);
1876 ret = PTR_ERR_OR_ZERO(ptr: u);
1877 if (ret)
1878 return ret;
1879
1880 bch2_extent_normalize(c, bkey_i_to_s(k: u));
1881 return 0;
1882}
1883
1884static int bch2_alloc_write_oldest_gen(struct btree_trans *trans, struct btree_iter *iter,
1885 struct bkey_s_c k)
1886{
1887 struct bch_dev *ca = bch_dev_bkey_exists(c: trans->c, idx: iter->pos.inode);
1888 struct bch_alloc_v4 a_convert;
1889 const struct bch_alloc_v4 *a = bch2_alloc_to_v4(k, convert: &a_convert);
1890 struct bkey_i_alloc_v4 *a_mut;
1891 int ret;
1892
1893 if (a->oldest_gen == ca->oldest_gen[iter->pos.offset])
1894 return 0;
1895
1896 a_mut = bch2_alloc_to_v4_mut(trans, k);
1897 ret = PTR_ERR_OR_ZERO(ptr: a_mut);
1898 if (ret)
1899 return ret;
1900
1901 a_mut->v.oldest_gen = ca->oldest_gen[iter->pos.offset];
1902 a_mut->v.data_type = alloc_data_type(a: a_mut->v, data_type: a_mut->v.data_type);
1903
1904 return bch2_trans_update(trans, iter, &a_mut->k_i, 0);
1905}
1906
1907int bch2_gc_gens(struct bch_fs *c)
1908{
1909 u64 b, start_time = local_clock();
1910 int ret;
1911
1912 /*
1913 * Ideally we would be using state_lock and not gc_lock here, but that
1914 * introduces a deadlock in the RO path - we currently take the state
1915 * lock at the start of going RO, thus the gc thread may get stuck:
1916 */
1917 if (!mutex_trylock(lock: &c->gc_gens_lock))
1918 return 0;
1919
1920 trace_and_count(c, gc_gens_start, c);
1921 down_read(sem: &c->gc_lock);
1922
1923 for_each_member_device(c, ca) {
1924 struct bucket_gens *gens = bucket_gens(ca);
1925
1926 BUG_ON(ca->oldest_gen);
1927
1928 ca->oldest_gen = kvmalloc(size: gens->nbuckets, GFP_KERNEL);
1929 if (!ca->oldest_gen) {
1930 percpu_ref_put(ref: &ca->ref);
1931 ret = -BCH_ERR_ENOMEM_gc_gens;
1932 goto err;
1933 }
1934
1935 for (b = gens->first_bucket;
1936 b < gens->nbuckets; b++)
1937 ca->oldest_gen[b] = gens->b[b];
1938 }
1939
1940 for (unsigned i = 0; i < BTREE_ID_NR; i++)
1941 if (btree_type_has_ptrs(id: i)) {
1942 c->gc_gens_btree = i;
1943 c->gc_gens_pos = POS_MIN;
1944
1945 ret = bch2_trans_run(c,
1946 for_each_btree_key_commit(trans, iter, i,
1947 POS_MIN,
1948 BTREE_ITER_PREFETCH|BTREE_ITER_ALL_SNAPSHOTS,
1949 k,
1950 NULL, NULL,
1951 BCH_TRANS_COMMIT_no_enospc,
1952 gc_btree_gens_key(trans, &iter, k)));
1953 if (ret)
1954 goto err;
1955 }
1956
1957 ret = bch2_trans_run(c,
1958 for_each_btree_key_commit(trans, iter, BTREE_ID_alloc,
1959 POS_MIN,
1960 BTREE_ITER_PREFETCH,
1961 k,
1962 NULL, NULL,
1963 BCH_TRANS_COMMIT_no_enospc,
1964 bch2_alloc_write_oldest_gen(trans, &iter, k)));
1965 if (ret)
1966 goto err;
1967
1968 c->gc_gens_btree = 0;
1969 c->gc_gens_pos = POS_MIN;
1970
1971 c->gc_count++;
1972
1973 bch2_time_stats_update(stats: &c->times[BCH_TIME_btree_gc], start: start_time);
1974 trace_and_count(c, gc_gens_end, c);
1975err:
1976 for_each_member_device(c, ca) {
1977 kvfree(addr: ca->oldest_gen);
1978 ca->oldest_gen = NULL;
1979 }
1980
1981 up_read(sem: &c->gc_lock);
1982 mutex_unlock(lock: &c->gc_gens_lock);
1983 if (!bch2_err_matches(ret, EROFS))
1984 bch_err_fn(c, ret);
1985 return ret;
1986}
1987
1988static int bch2_gc_thread(void *arg)
1989{
1990 struct bch_fs *c = arg;
1991 struct io_clock *clock = &c->io_clock[WRITE];
1992 unsigned long last = atomic64_read(v: &clock->now);
1993 unsigned last_kick = atomic_read(v: &c->kick_gc);
1994
1995 set_freezable();
1996
1997 while (1) {
1998 while (1) {
1999 set_current_state(TASK_INTERRUPTIBLE);
2000
2001 if (kthread_should_stop()) {
2002 __set_current_state(TASK_RUNNING);
2003 return 0;
2004 }
2005
2006 if (atomic_read(v: &c->kick_gc) != last_kick)
2007 break;
2008
2009 if (c->btree_gc_periodic) {
2010 unsigned long next = last + c->capacity / 16;
2011
2012 if (atomic64_read(v: &clock->now) >= next)
2013 break;
2014
2015 bch2_io_clock_schedule_timeout(clock, next);
2016 } else {
2017 schedule();
2018 }
2019
2020 try_to_freeze();
2021 }
2022 __set_current_state(TASK_RUNNING);
2023
2024 last = atomic64_read(v: &clock->now);
2025 last_kick = atomic_read(v: &c->kick_gc);
2026
2027 /*
2028 * Full gc is currently incompatible with btree key cache:
2029 */
2030#if 0
2031 ret = bch2_gc(c, false, false);
2032#else
2033 bch2_gc_gens(c);
2034#endif
2035 debug_check_no_locks_held();
2036 }
2037
2038 return 0;
2039}
2040
2041void bch2_gc_thread_stop(struct bch_fs *c)
2042{
2043 struct task_struct *p;
2044
2045 p = c->gc_thread;
2046 c->gc_thread = NULL;
2047
2048 if (p) {
2049 kthread_stop(k: p);
2050 put_task_struct(t: p);
2051 }
2052}
2053
2054int bch2_gc_thread_start(struct bch_fs *c)
2055{
2056 struct task_struct *p;
2057
2058 if (c->gc_thread)
2059 return 0;
2060
2061 p = kthread_create(bch2_gc_thread, c, "bch-gc/%s", c->name);
2062 if (IS_ERR(ptr: p)) {
2063 bch_err_fn(c, PTR_ERR(p));
2064 return PTR_ERR(ptr: p);
2065 }
2066
2067 get_task_struct(t: p);
2068 c->gc_thread = p;
2069 wake_up_process(tsk: p);
2070 return 0;
2071}
2072

source code of linux/fs/bcachefs/btree_gc.c