xref: /linux/fs/bcachefs/btree_io.c (revision 173b0b5b0e865348684c02bd9cb1d22b5d46e458)
1 // SPDX-License-Identifier: GPL-2.0
2 
3 #include "bcachefs.h"
4 #include "bkey_methods.h"
5 #include "bkey_sort.h"
6 #include "btree_cache.h"
7 #include "btree_io.h"
8 #include "btree_iter.h"
9 #include "btree_locking.h"
10 #include "btree_update.h"
11 #include "btree_update_interior.h"
12 #include "buckets.h"
13 #include "checksum.h"
14 #include "debug.h"
15 #include "error.h"
16 #include "extents.h"
17 #include "io_write.h"
18 #include "journal_reclaim.h"
19 #include "journal_seq_blacklist.h"
20 #include "recovery.h"
21 #include "super-io.h"
22 #include "trace.h"
23 
24 #include <linux/sched/mm.h>
25 
26 void bch2_btree_node_io_unlock(struct btree *b)
27 {
28 	EBUG_ON(!btree_node_write_in_flight(b));
29 
30 	clear_btree_node_write_in_flight_inner(b);
31 	clear_btree_node_write_in_flight(b);
32 	wake_up_bit(&b->flags, BTREE_NODE_write_in_flight);
33 }
34 
35 void bch2_btree_node_io_lock(struct btree *b)
36 {
37 	bch2_assert_btree_nodes_not_locked();
38 
39 	wait_on_bit_lock_io(&b->flags, BTREE_NODE_write_in_flight,
40 			    TASK_UNINTERRUPTIBLE);
41 }
42 
43 void __bch2_btree_node_wait_on_read(struct btree *b)
44 {
45 	wait_on_bit_io(&b->flags, BTREE_NODE_read_in_flight,
46 		       TASK_UNINTERRUPTIBLE);
47 }
48 
49 void __bch2_btree_node_wait_on_write(struct btree *b)
50 {
51 	wait_on_bit_io(&b->flags, BTREE_NODE_write_in_flight,
52 		       TASK_UNINTERRUPTIBLE);
53 }
54 
55 void bch2_btree_node_wait_on_read(struct btree *b)
56 {
57 	bch2_assert_btree_nodes_not_locked();
58 
59 	wait_on_bit_io(&b->flags, BTREE_NODE_read_in_flight,
60 		       TASK_UNINTERRUPTIBLE);
61 }
62 
63 void bch2_btree_node_wait_on_write(struct btree *b)
64 {
65 	bch2_assert_btree_nodes_not_locked();
66 
67 	wait_on_bit_io(&b->flags, BTREE_NODE_write_in_flight,
68 		       TASK_UNINTERRUPTIBLE);
69 }
70 
71 static void verify_no_dups(struct btree *b,
72 			   struct bkey_packed *start,
73 			   struct bkey_packed *end)
74 {
75 #ifdef CONFIG_BCACHEFS_DEBUG
76 	struct bkey_packed *k, *p;
77 
78 	if (start == end)
79 		return;
80 
81 	for (p = start, k = bkey_p_next(start);
82 	     k != end;
83 	     p = k, k = bkey_p_next(k)) {
84 		struct bkey l = bkey_unpack_key(b, p);
85 		struct bkey r = bkey_unpack_key(b, k);
86 
87 		BUG_ON(bpos_ge(l.p, bkey_start_pos(&r)));
88 	}
89 #endif
90 }
91 
92 static void set_needs_whiteout(struct bset *i, int v)
93 {
94 	struct bkey_packed *k;
95 
96 	for (k = i->start; k != vstruct_last(i); k = bkey_p_next(k))
97 		k->needs_whiteout = v;
98 }
99 
100 static void btree_bounce_free(struct bch_fs *c, size_t size,
101 			      bool used_mempool, void *p)
102 {
103 	if (used_mempool)
104 		mempool_free(p, &c->btree_bounce_pool);
105 	else
106 		kvfree(p);
107 }
108 
109 static void *btree_bounce_alloc(struct bch_fs *c, size_t size,
110 				bool *used_mempool)
111 {
112 	unsigned flags = memalloc_nofs_save();
113 	void *p;
114 
115 	BUG_ON(size > c->opts.btree_node_size);
116 
117 	*used_mempool = false;
118 	p = kvmalloc(size, __GFP_NOWARN|GFP_NOWAIT);
119 	if (!p) {
120 		*used_mempool = true;
121 		p = mempool_alloc(&c->btree_bounce_pool, GFP_NOFS);
122 	}
123 	memalloc_nofs_restore(flags);
124 	return p;
125 }
126 
127 static void sort_bkey_ptrs(const struct btree *bt,
128 			   struct bkey_packed **ptrs, unsigned nr)
129 {
130 	unsigned n = nr, a = nr / 2, b, c, d;
131 
132 	if (!a)
133 		return;
134 
135 	/* Heap sort: see lib/sort.c: */
136 	while (1) {
137 		if (a)
138 			a--;
139 		else if (--n)
140 			swap(ptrs[0], ptrs[n]);
141 		else
142 			break;
143 
144 		for (b = a; c = 2 * b + 1, (d = c + 1) < n;)
145 			b = bch2_bkey_cmp_packed(bt,
146 					    ptrs[c],
147 					    ptrs[d]) >= 0 ? c : d;
148 		if (d == n)
149 			b = c;
150 
151 		while (b != a &&
152 		       bch2_bkey_cmp_packed(bt,
153 				       ptrs[a],
154 				       ptrs[b]) >= 0)
155 			b = (b - 1) / 2;
156 		c = b;
157 		while (b != a) {
158 			b = (b - 1) / 2;
159 			swap(ptrs[b], ptrs[c]);
160 		}
161 	}
162 }
163 
164 static void bch2_sort_whiteouts(struct bch_fs *c, struct btree *b)
165 {
166 	struct bkey_packed *new_whiteouts, **ptrs, **ptrs_end, *k;
167 	bool used_mempool = false;
168 	size_t bytes = b->whiteout_u64s * sizeof(u64);
169 
170 	if (!b->whiteout_u64s)
171 		return;
172 
173 	new_whiteouts = btree_bounce_alloc(c, bytes, &used_mempool);
174 
175 	ptrs = ptrs_end = ((void *) new_whiteouts + bytes);
176 
177 	for (k = unwritten_whiteouts_start(b);
178 	     k != unwritten_whiteouts_end(b);
179 	     k = bkey_p_next(k))
180 		*--ptrs = k;
181 
182 	sort_bkey_ptrs(b, ptrs, ptrs_end - ptrs);
183 
184 	k = new_whiteouts;
185 
186 	while (ptrs != ptrs_end) {
187 		bkey_p_copy(k, *ptrs);
188 		k = bkey_p_next(k);
189 		ptrs++;
190 	}
191 
192 	verify_no_dups(b, new_whiteouts,
193 		       (void *) ((u64 *) new_whiteouts + b->whiteout_u64s));
194 
195 	memcpy_u64s(unwritten_whiteouts_start(b),
196 		    new_whiteouts, b->whiteout_u64s);
197 
198 	btree_bounce_free(c, bytes, used_mempool, new_whiteouts);
199 }
200 
201 static bool should_compact_bset(struct btree *b, struct bset_tree *t,
202 				bool compacting, enum compact_mode mode)
203 {
204 	if (!bset_dead_u64s(b, t))
205 		return false;
206 
207 	switch (mode) {
208 	case COMPACT_LAZY:
209 		return should_compact_bset_lazy(b, t) ||
210 			(compacting && !bset_written(b, bset(b, t)));
211 	case COMPACT_ALL:
212 		return true;
213 	default:
214 		BUG();
215 	}
216 }
217 
218 static bool bch2_drop_whiteouts(struct btree *b, enum compact_mode mode)
219 {
220 	struct bset_tree *t;
221 	bool ret = false;
222 
223 	for_each_bset(b, t) {
224 		struct bset *i = bset(b, t);
225 		struct bkey_packed *k, *n, *out, *start, *end;
226 		struct btree_node_entry *src = NULL, *dst = NULL;
227 
228 		if (t != b->set && !bset_written(b, i)) {
229 			src = container_of(i, struct btree_node_entry, keys);
230 			dst = max(write_block(b),
231 				  (void *) btree_bkey_last(b, t - 1));
232 		}
233 
234 		if (src != dst)
235 			ret = true;
236 
237 		if (!should_compact_bset(b, t, ret, mode)) {
238 			if (src != dst) {
239 				memmove(dst, src, sizeof(*src) +
240 					le16_to_cpu(src->keys.u64s) *
241 					sizeof(u64));
242 				i = &dst->keys;
243 				set_btree_bset(b, t, i);
244 			}
245 			continue;
246 		}
247 
248 		start	= btree_bkey_first(b, t);
249 		end	= btree_bkey_last(b, t);
250 
251 		if (src != dst) {
252 			memmove(dst, src, sizeof(*src));
253 			i = &dst->keys;
254 			set_btree_bset(b, t, i);
255 		}
256 
257 		out = i->start;
258 
259 		for (k = start; k != end; k = n) {
260 			n = bkey_p_next(k);
261 
262 			if (!bkey_deleted(k)) {
263 				bkey_p_copy(out, k);
264 				out = bkey_p_next(out);
265 			} else {
266 				BUG_ON(k->needs_whiteout);
267 			}
268 		}
269 
270 		i->u64s = cpu_to_le16((u64 *) out - i->_data);
271 		set_btree_bset_end(b, t);
272 		bch2_bset_set_no_aux_tree(b, t);
273 		ret = true;
274 	}
275 
276 	bch2_verify_btree_nr_keys(b);
277 
278 	bch2_btree_build_aux_trees(b);
279 
280 	return ret;
281 }
282 
283 bool bch2_compact_whiteouts(struct bch_fs *c, struct btree *b,
284 			    enum compact_mode mode)
285 {
286 	return bch2_drop_whiteouts(b, mode);
287 }
288 
289 static void btree_node_sort(struct bch_fs *c, struct btree *b,
290 			    unsigned start_idx,
291 			    unsigned end_idx,
292 			    bool filter_whiteouts)
293 {
294 	struct btree_node *out;
295 	struct sort_iter_stack sort_iter;
296 	struct bset_tree *t;
297 	struct bset *start_bset = bset(b, &b->set[start_idx]);
298 	bool used_mempool = false;
299 	u64 start_time, seq = 0;
300 	unsigned i, u64s = 0, bytes, shift = end_idx - start_idx - 1;
301 	bool sorting_entire_node = start_idx == 0 &&
302 		end_idx == b->nsets;
303 
304 	sort_iter_stack_init(&sort_iter, b);
305 
306 	for (t = b->set + start_idx;
307 	     t < b->set + end_idx;
308 	     t++) {
309 		u64s += le16_to_cpu(bset(b, t)->u64s);
310 		sort_iter_add(&sort_iter.iter,
311 			      btree_bkey_first(b, t),
312 			      btree_bkey_last(b, t));
313 	}
314 
315 	bytes = sorting_entire_node
316 		? btree_buf_bytes(b)
317 		: __vstruct_bytes(struct btree_node, u64s);
318 
319 	out = btree_bounce_alloc(c, bytes, &used_mempool);
320 
321 	start_time = local_clock();
322 
323 	u64s = bch2_sort_keys(out->keys.start, &sort_iter.iter, filter_whiteouts);
324 
325 	out->keys.u64s = cpu_to_le16(u64s);
326 
327 	BUG_ON(vstruct_end(&out->keys) > (void *) out + bytes);
328 
329 	if (sorting_entire_node)
330 		bch2_time_stats_update(&c->times[BCH_TIME_btree_node_sort],
331 				       start_time);
332 
333 	/* Make sure we preserve bset journal_seq: */
334 	for (t = b->set + start_idx; t < b->set + end_idx; t++)
335 		seq = max(seq, le64_to_cpu(bset(b, t)->journal_seq));
336 	start_bset->journal_seq = cpu_to_le64(seq);
337 
338 	if (sorting_entire_node) {
339 		u64s = le16_to_cpu(out->keys.u64s);
340 
341 		BUG_ON(bytes != btree_buf_bytes(b));
342 
343 		/*
344 		 * Our temporary buffer is the same size as the btree node's
345 		 * buffer, we can just swap buffers instead of doing a big
346 		 * memcpy()
347 		 */
348 		*out = *b->data;
349 		out->keys.u64s = cpu_to_le16(u64s);
350 		swap(out, b->data);
351 		set_btree_bset(b, b->set, &b->data->keys);
352 	} else {
353 		start_bset->u64s = out->keys.u64s;
354 		memcpy_u64s(start_bset->start,
355 			    out->keys.start,
356 			    le16_to_cpu(out->keys.u64s));
357 	}
358 
359 	for (i = start_idx + 1; i < end_idx; i++)
360 		b->nr.bset_u64s[start_idx] +=
361 			b->nr.bset_u64s[i];
362 
363 	b->nsets -= shift;
364 
365 	for (i = start_idx + 1; i < b->nsets; i++) {
366 		b->nr.bset_u64s[i]	= b->nr.bset_u64s[i + shift];
367 		b->set[i]		= b->set[i + shift];
368 	}
369 
370 	for (i = b->nsets; i < MAX_BSETS; i++)
371 		b->nr.bset_u64s[i] = 0;
372 
373 	set_btree_bset_end(b, &b->set[start_idx]);
374 	bch2_bset_set_no_aux_tree(b, &b->set[start_idx]);
375 
376 	btree_bounce_free(c, bytes, used_mempool, out);
377 
378 	bch2_verify_btree_nr_keys(b);
379 }
380 
381 void bch2_btree_sort_into(struct bch_fs *c,
382 			 struct btree *dst,
383 			 struct btree *src)
384 {
385 	struct btree_nr_keys nr;
386 	struct btree_node_iter src_iter;
387 	u64 start_time = local_clock();
388 
389 	BUG_ON(dst->nsets != 1);
390 
391 	bch2_bset_set_no_aux_tree(dst, dst->set);
392 
393 	bch2_btree_node_iter_init_from_start(&src_iter, src);
394 
395 	nr = bch2_sort_repack(btree_bset_first(dst),
396 			src, &src_iter,
397 			&dst->format,
398 			true);
399 
400 	bch2_time_stats_update(&c->times[BCH_TIME_btree_node_sort],
401 			       start_time);
402 
403 	set_btree_bset_end(dst, dst->set);
404 
405 	dst->nr.live_u64s	+= nr.live_u64s;
406 	dst->nr.bset_u64s[0]	+= nr.bset_u64s[0];
407 	dst->nr.packed_keys	+= nr.packed_keys;
408 	dst->nr.unpacked_keys	+= nr.unpacked_keys;
409 
410 	bch2_verify_btree_nr_keys(dst);
411 }
412 
413 /*
414  * We're about to add another bset to the btree node, so if there's currently
415  * too many bsets - sort some of them together:
416  */
417 static bool btree_node_compact(struct bch_fs *c, struct btree *b)
418 {
419 	unsigned unwritten_idx;
420 	bool ret = false;
421 
422 	for (unwritten_idx = 0;
423 	     unwritten_idx < b->nsets;
424 	     unwritten_idx++)
425 		if (!bset_written(b, bset(b, &b->set[unwritten_idx])))
426 			break;
427 
428 	if (b->nsets - unwritten_idx > 1) {
429 		btree_node_sort(c, b, unwritten_idx,
430 				b->nsets, false);
431 		ret = true;
432 	}
433 
434 	if (unwritten_idx > 1) {
435 		btree_node_sort(c, b, 0, unwritten_idx, false);
436 		ret = true;
437 	}
438 
439 	return ret;
440 }
441 
442 void bch2_btree_build_aux_trees(struct btree *b)
443 {
444 	struct bset_tree *t;
445 
446 	for_each_bset(b, t)
447 		bch2_bset_build_aux_tree(b, t,
448 				!bset_written(b, bset(b, t)) &&
449 				t == bset_tree_last(b));
450 }
451 
452 /*
453  * If we have MAX_BSETS (3) bsets, should we sort them all down to just one?
454  *
455  * The first bset is going to be of similar order to the size of the node, the
456  * last bset is bounded by btree_write_set_buffer(), which is set to keep the
457  * memmove on insert from being too expensive: the middle bset should, ideally,
458  * be the geometric mean of the first and the last.
459  *
460  * Returns true if the middle bset is greater than that geometric mean:
461  */
462 static inline bool should_compact_all(struct bch_fs *c, struct btree *b)
463 {
464 	unsigned mid_u64s_bits =
465 		(ilog2(btree_max_u64s(c)) + BTREE_WRITE_SET_U64s_BITS) / 2;
466 
467 	return bset_u64s(&b->set[1]) > 1U << mid_u64s_bits;
468 }
469 
470 /*
471  * @bch_btree_init_next - initialize a new (unwritten) bset that can then be
472  * inserted into
473  *
474  * Safe to call if there already is an unwritten bset - will only add a new bset
475  * if @b doesn't already have one.
476  *
477  * Returns true if we sorted (i.e. invalidated iterators
478  */
479 void bch2_btree_init_next(struct btree_trans *trans, struct btree *b)
480 {
481 	struct bch_fs *c = trans->c;
482 	struct btree_node_entry *bne;
483 	bool reinit_iter = false;
484 
485 	EBUG_ON(!six_lock_counts(&b->c.lock).n[SIX_LOCK_write]);
486 	BUG_ON(bset_written(b, bset(b, &b->set[1])));
487 	BUG_ON(btree_node_just_written(b));
488 
489 	if (b->nsets == MAX_BSETS &&
490 	    !btree_node_write_in_flight(b) &&
491 	    should_compact_all(c, b)) {
492 		bch2_btree_node_write(c, b, SIX_LOCK_write,
493 				      BTREE_WRITE_init_next_bset);
494 		reinit_iter = true;
495 	}
496 
497 	if (b->nsets == MAX_BSETS &&
498 	    btree_node_compact(c, b))
499 		reinit_iter = true;
500 
501 	BUG_ON(b->nsets >= MAX_BSETS);
502 
503 	bne = want_new_bset(c, b);
504 	if (bne)
505 		bch2_bset_init_next(b, bne);
506 
507 	bch2_btree_build_aux_trees(b);
508 
509 	if (reinit_iter)
510 		bch2_trans_node_reinit_iter(trans, b);
511 }
512 
513 static void btree_err_msg(struct printbuf *out, struct bch_fs *c,
514 			  struct bch_dev *ca,
515 			  struct btree *b, struct bset *i,
516 			  unsigned offset, int write)
517 {
518 	prt_printf(out, bch2_log_msg(c, "%s"),
519 		   write == READ
520 		   ? "error validating btree node "
521 		   : "corrupt btree node before write ");
522 	if (ca)
523 		prt_printf(out, "on %s ", ca->name);
524 	prt_printf(out, "at btree ");
525 	bch2_btree_pos_to_text(out, c, b);
526 
527 	prt_printf(out, "\n  node offset %u/%u",
528 		   b->written, btree_ptr_sectors_written(&b->key));
529 	if (i)
530 		prt_printf(out, " bset u64s %u", le16_to_cpu(i->u64s));
531 	prt_str(out, ": ");
532 }
533 
534 __printf(9, 10)
535 static int __btree_err(int ret,
536 		       struct bch_fs *c,
537 		       struct bch_dev *ca,
538 		       struct btree *b,
539 		       struct bset *i,
540 		       int write,
541 		       bool have_retry,
542 		       enum bch_sb_error_id err_type,
543 		       const char *fmt, ...)
544 {
545 	struct printbuf out = PRINTBUF;
546 	va_list args;
547 
548 	btree_err_msg(&out, c, ca, b, i, b->written, write);
549 
550 	va_start(args, fmt);
551 	prt_vprintf(&out, fmt, args);
552 	va_end(args);
553 
554 	if (write == WRITE) {
555 		bch2_print_string_as_lines(KERN_ERR, out.buf);
556 		ret = c->opts.errors == BCH_ON_ERROR_continue
557 			? 0
558 			: -BCH_ERR_fsck_errors_not_fixed;
559 		goto out;
560 	}
561 
562 	if (!have_retry && ret == -BCH_ERR_btree_node_read_err_want_retry)
563 		ret = -BCH_ERR_btree_node_read_err_fixable;
564 	if (!have_retry && ret == -BCH_ERR_btree_node_read_err_must_retry)
565 		ret = -BCH_ERR_btree_node_read_err_bad_node;
566 
567 	if (ret != -BCH_ERR_btree_node_read_err_fixable)
568 		bch2_sb_error_count(c, err_type);
569 
570 	switch (ret) {
571 	case -BCH_ERR_btree_node_read_err_fixable:
572 		ret = bch2_fsck_err(c, FSCK_CAN_FIX, err_type, "%s", out.buf);
573 		if (ret != -BCH_ERR_fsck_fix &&
574 		    ret != -BCH_ERR_fsck_ignore)
575 			goto fsck_err;
576 		ret = -BCH_ERR_fsck_fix;
577 		break;
578 	case -BCH_ERR_btree_node_read_err_want_retry:
579 	case -BCH_ERR_btree_node_read_err_must_retry:
580 		bch2_print_string_as_lines(KERN_ERR, out.buf);
581 		break;
582 	case -BCH_ERR_btree_node_read_err_bad_node:
583 		bch2_print_string_as_lines(KERN_ERR, out.buf);
584 		ret = bch2_topology_error(c);
585 		break;
586 	case -BCH_ERR_btree_node_read_err_incompatible:
587 		bch2_print_string_as_lines(KERN_ERR, out.buf);
588 		ret = -BCH_ERR_fsck_errors_not_fixed;
589 		break;
590 	default:
591 		BUG();
592 	}
593 out:
594 fsck_err:
595 	printbuf_exit(&out);
596 	return ret;
597 }
598 
599 #define btree_err(type, c, ca, b, i, _err_type, msg, ...)		\
600 ({									\
601 	int _ret = __btree_err(type, c, ca, b, i, write, have_retry,	\
602 			       BCH_FSCK_ERR_##_err_type,		\
603 			       msg, ##__VA_ARGS__);			\
604 									\
605 	if (_ret != -BCH_ERR_fsck_fix) {				\
606 		ret = _ret;						\
607 		goto fsck_err;						\
608 	}								\
609 									\
610 	*saw_error = true;						\
611 })
612 
613 #define btree_err_on(cond, ...)	((cond) ? btree_err(__VA_ARGS__) : false)
614 
615 /*
616  * When btree topology repair changes the start or end of a node, that might
617  * mean we have to drop keys that are no longer inside the node:
618  */
619 __cold
620 void bch2_btree_node_drop_keys_outside_node(struct btree *b)
621 {
622 	struct bset_tree *t;
623 
624 	for_each_bset(b, t) {
625 		struct bset *i = bset(b, t);
626 		struct bkey_packed *k;
627 
628 		for (k = i->start; k != vstruct_last(i); k = bkey_p_next(k))
629 			if (bkey_cmp_left_packed(b, k, &b->data->min_key) >= 0)
630 				break;
631 
632 		if (k != i->start) {
633 			unsigned shift = (u64 *) k - (u64 *) i->start;
634 
635 			memmove_u64s_down(i->start, k,
636 					  (u64 *) vstruct_end(i) - (u64 *) k);
637 			i->u64s = cpu_to_le16(le16_to_cpu(i->u64s) - shift);
638 			set_btree_bset_end(b, t);
639 		}
640 
641 		for (k = i->start; k != vstruct_last(i); k = bkey_p_next(k))
642 			if (bkey_cmp_left_packed(b, k, &b->data->max_key) > 0)
643 				break;
644 
645 		if (k != vstruct_last(i)) {
646 			i->u64s = cpu_to_le16((u64 *) k - (u64 *) i->start);
647 			set_btree_bset_end(b, t);
648 		}
649 	}
650 
651 	/*
652 	 * Always rebuild search trees: eytzinger search tree nodes directly
653 	 * depend on the values of min/max key:
654 	 */
655 	bch2_bset_set_no_aux_tree(b, b->set);
656 	bch2_btree_build_aux_trees(b);
657 	b->nr = bch2_btree_node_count_keys(b);
658 
659 	struct bkey_s_c k;
660 	struct bkey unpacked;
661 	struct btree_node_iter iter;
662 	for_each_btree_node_key_unpack(b, k, &iter, &unpacked) {
663 		BUG_ON(bpos_lt(k.k->p, b->data->min_key));
664 		BUG_ON(bpos_gt(k.k->p, b->data->max_key));
665 	}
666 }
667 
668 static int validate_bset(struct bch_fs *c, struct bch_dev *ca,
669 			 struct btree *b, struct bset *i,
670 			 unsigned offset, unsigned sectors,
671 			 int write, bool have_retry, bool *saw_error)
672 {
673 	unsigned version = le16_to_cpu(i->version);
674 	struct printbuf buf1 = PRINTBUF;
675 	struct printbuf buf2 = PRINTBUF;
676 	int ret = 0;
677 
678 	btree_err_on(!bch2_version_compatible(version),
679 		     -BCH_ERR_btree_node_read_err_incompatible,
680 		     c, ca, b, i,
681 		     btree_node_unsupported_version,
682 		     "unsupported bset version %u.%u",
683 		     BCH_VERSION_MAJOR(version),
684 		     BCH_VERSION_MINOR(version));
685 
686 	if (btree_err_on(version < c->sb.version_min,
687 			 -BCH_ERR_btree_node_read_err_fixable,
688 			 c, NULL, b, i,
689 			 btree_node_bset_older_than_sb_min,
690 			 "bset version %u older than superblock version_min %u",
691 			 version, c->sb.version_min)) {
692 		mutex_lock(&c->sb_lock);
693 		c->disk_sb.sb->version_min = cpu_to_le16(version);
694 		bch2_write_super(c);
695 		mutex_unlock(&c->sb_lock);
696 	}
697 
698 	if (btree_err_on(BCH_VERSION_MAJOR(version) >
699 			 BCH_VERSION_MAJOR(c->sb.version),
700 			 -BCH_ERR_btree_node_read_err_fixable,
701 			 c, NULL, b, i,
702 			 btree_node_bset_newer_than_sb,
703 			 "bset version %u newer than superblock version %u",
704 			 version, c->sb.version)) {
705 		mutex_lock(&c->sb_lock);
706 		c->disk_sb.sb->version = cpu_to_le16(version);
707 		bch2_write_super(c);
708 		mutex_unlock(&c->sb_lock);
709 	}
710 
711 	btree_err_on(BSET_SEPARATE_WHITEOUTS(i),
712 		     -BCH_ERR_btree_node_read_err_incompatible,
713 		     c, ca, b, i,
714 		     btree_node_unsupported_version,
715 		     "BSET_SEPARATE_WHITEOUTS no longer supported");
716 
717 	if (btree_err_on(offset + sectors > btree_sectors(c),
718 			 -BCH_ERR_btree_node_read_err_fixable,
719 			 c, ca, b, i,
720 			 bset_past_end_of_btree_node,
721 			 "bset past end of btree node")) {
722 		i->u64s = 0;
723 		ret = 0;
724 		goto out;
725 	}
726 
727 	btree_err_on(offset && !i->u64s,
728 		     -BCH_ERR_btree_node_read_err_fixable,
729 		     c, ca, b, i,
730 		     bset_empty,
731 		     "empty bset");
732 
733 	btree_err_on(BSET_OFFSET(i) && BSET_OFFSET(i) != offset,
734 		     -BCH_ERR_btree_node_read_err_want_retry,
735 		     c, ca, b, i,
736 		     bset_wrong_sector_offset,
737 		     "bset at wrong sector offset");
738 
739 	if (!offset) {
740 		struct btree_node *bn =
741 			container_of(i, struct btree_node, keys);
742 		/* These indicate that we read the wrong btree node: */
743 
744 		if (b->key.k.type == KEY_TYPE_btree_ptr_v2) {
745 			struct bch_btree_ptr_v2 *bp =
746 				&bkey_i_to_btree_ptr_v2(&b->key)->v;
747 
748 			/* XXX endianness */
749 			btree_err_on(bp->seq != bn->keys.seq,
750 				     -BCH_ERR_btree_node_read_err_must_retry,
751 				     c, ca, b, NULL,
752 				     bset_bad_seq,
753 				     "incorrect sequence number (wrong btree node)");
754 		}
755 
756 		btree_err_on(BTREE_NODE_ID(bn) != b->c.btree_id,
757 			     -BCH_ERR_btree_node_read_err_must_retry,
758 			     c, ca, b, i,
759 			     btree_node_bad_btree,
760 			     "incorrect btree id");
761 
762 		btree_err_on(BTREE_NODE_LEVEL(bn) != b->c.level,
763 			     -BCH_ERR_btree_node_read_err_must_retry,
764 			     c, ca, b, i,
765 			     btree_node_bad_level,
766 			     "incorrect level");
767 
768 		if (!write)
769 			compat_btree_node(b->c.level, b->c.btree_id, version,
770 					  BSET_BIG_ENDIAN(i), write, bn);
771 
772 		if (b->key.k.type == KEY_TYPE_btree_ptr_v2) {
773 			struct bch_btree_ptr_v2 *bp =
774 				&bkey_i_to_btree_ptr_v2(&b->key)->v;
775 
776 			if (BTREE_PTR_RANGE_UPDATED(bp)) {
777 				b->data->min_key = bp->min_key;
778 				b->data->max_key = b->key.k.p;
779 			}
780 
781 			btree_err_on(!bpos_eq(b->data->min_key, bp->min_key),
782 				     -BCH_ERR_btree_node_read_err_must_retry,
783 				     c, ca, b, NULL,
784 				     btree_node_bad_min_key,
785 				     "incorrect min_key: got %s should be %s",
786 				     (printbuf_reset(&buf1),
787 				      bch2_bpos_to_text(&buf1, bn->min_key), buf1.buf),
788 				     (printbuf_reset(&buf2),
789 				      bch2_bpos_to_text(&buf2, bp->min_key), buf2.buf));
790 		}
791 
792 		btree_err_on(!bpos_eq(bn->max_key, b->key.k.p),
793 			     -BCH_ERR_btree_node_read_err_must_retry,
794 			     c, ca, b, i,
795 			     btree_node_bad_max_key,
796 			     "incorrect max key %s",
797 			     (printbuf_reset(&buf1),
798 			      bch2_bpos_to_text(&buf1, bn->max_key), buf1.buf));
799 
800 		if (write)
801 			compat_btree_node(b->c.level, b->c.btree_id, version,
802 					  BSET_BIG_ENDIAN(i), write, bn);
803 
804 		btree_err_on(bch2_bkey_format_invalid(c, &bn->format, write, &buf1),
805 			     -BCH_ERR_btree_node_read_err_bad_node,
806 			     c, ca, b, i,
807 			     btree_node_bad_format,
808 			     "invalid bkey format: %s\n  %s", buf1.buf,
809 			     (printbuf_reset(&buf2),
810 			      bch2_bkey_format_to_text(&buf2, &bn->format), buf2.buf));
811 		printbuf_reset(&buf1);
812 
813 		compat_bformat(b->c.level, b->c.btree_id, version,
814 			       BSET_BIG_ENDIAN(i), write,
815 			       &bn->format);
816 	}
817 out:
818 fsck_err:
819 	printbuf_exit(&buf2);
820 	printbuf_exit(&buf1);
821 	return ret;
822 }
823 
824 static int bset_key_invalid(struct bch_fs *c, struct btree *b,
825 			    struct bkey_s_c k,
826 			    bool updated_range, int rw,
827 			    struct printbuf *err)
828 {
829 	return __bch2_bkey_invalid(c, k, btree_node_type(b), READ, err) ?:
830 		(!updated_range ? bch2_bkey_in_btree_node(c, b, k, err) : 0) ?:
831 		(rw == WRITE ? bch2_bkey_val_invalid(c, k, READ, err) : 0);
832 }
833 
834 static bool bkey_packed_valid(struct bch_fs *c, struct btree *b,
835 			 struct bset *i, struct bkey_packed *k)
836 {
837 	if (bkey_p_next(k) > vstruct_last(i))
838 		return false;
839 
840 	if (k->format > KEY_FORMAT_CURRENT)
841 		return false;
842 
843 	if (!bkeyp_u64s_valid(&b->format, k))
844 		return false;
845 
846 	struct printbuf buf = PRINTBUF;
847 	struct bkey tmp;
848 	struct bkey_s u = __bkey_disassemble(b, k, &tmp);
849 	bool ret = __bch2_bkey_invalid(c, u.s_c, btree_node_type(b), READ, &buf);
850 	printbuf_exit(&buf);
851 	return ret;
852 }
853 
854 static int validate_bset_keys(struct bch_fs *c, struct btree *b,
855 			 struct bset *i, int write,
856 			 bool have_retry, bool *saw_error)
857 {
858 	unsigned version = le16_to_cpu(i->version);
859 	struct bkey_packed *k, *prev = NULL;
860 	struct printbuf buf = PRINTBUF;
861 	bool updated_range = b->key.k.type == KEY_TYPE_btree_ptr_v2 &&
862 		BTREE_PTR_RANGE_UPDATED(&bkey_i_to_btree_ptr_v2(&b->key)->v);
863 	int ret = 0;
864 
865 	for (k = i->start;
866 	     k != vstruct_last(i);) {
867 		struct bkey_s u;
868 		struct bkey tmp;
869 		unsigned next_good_key;
870 
871 		if (btree_err_on(bkey_p_next(k) > vstruct_last(i),
872 				 -BCH_ERR_btree_node_read_err_fixable,
873 				 c, NULL, b, i,
874 				 btree_node_bkey_past_bset_end,
875 				 "key extends past end of bset")) {
876 			i->u64s = cpu_to_le16((u64 *) k - i->_data);
877 			break;
878 		}
879 
880 		if (btree_err_on(k->format > KEY_FORMAT_CURRENT,
881 				 -BCH_ERR_btree_node_read_err_fixable,
882 				 c, NULL, b, i,
883 				 btree_node_bkey_bad_format,
884 				 "invalid bkey format %u", k->format))
885 			goto drop_this_key;
886 
887 		if (btree_err_on(!bkeyp_u64s_valid(&b->format, k),
888 				 -BCH_ERR_btree_node_read_err_fixable,
889 				 c, NULL, b, i,
890 				 btree_node_bkey_bad_u64s,
891 				 "bad k->u64s %u (min %u max %lu)", k->u64s,
892 				 bkeyp_key_u64s(&b->format, k),
893 				 U8_MAX - BKEY_U64s + bkeyp_key_u64s(&b->format, k)))
894 			goto drop_this_key;
895 
896 		if (!write)
897 			bch2_bkey_compat(b->c.level, b->c.btree_id, version,
898 				    BSET_BIG_ENDIAN(i), write,
899 				    &b->format, k);
900 
901 		u = __bkey_disassemble(b, k, &tmp);
902 
903 		printbuf_reset(&buf);
904 		if (bset_key_invalid(c, b, u.s_c, updated_range, write, &buf)) {
905 			printbuf_reset(&buf);
906 			bset_key_invalid(c, b, u.s_c, updated_range, write, &buf);
907 			prt_printf(&buf, "\n  ");
908 			bch2_bkey_val_to_text(&buf, c, u.s_c);
909 
910 			btree_err(-BCH_ERR_btree_node_read_err_fixable,
911 				  c, NULL, b, i,
912 				  btree_node_bad_bkey,
913 				  "invalid bkey: %s", buf.buf);
914 			goto drop_this_key;
915 		}
916 
917 		if (write)
918 			bch2_bkey_compat(b->c.level, b->c.btree_id, version,
919 				    BSET_BIG_ENDIAN(i), write,
920 				    &b->format, k);
921 
922 		if (prev && bkey_iter_cmp(b, prev, k) > 0) {
923 			struct bkey up = bkey_unpack_key(b, prev);
924 
925 			printbuf_reset(&buf);
926 			prt_printf(&buf, "keys out of order: ");
927 			bch2_bkey_to_text(&buf, &up);
928 			prt_printf(&buf, " > ");
929 			bch2_bkey_to_text(&buf, u.k);
930 
931 			if (btree_err(-BCH_ERR_btree_node_read_err_fixable,
932 				      c, NULL, b, i,
933 				      btree_node_bkey_out_of_order,
934 				      "%s", buf.buf))
935 				goto drop_this_key;
936 		}
937 
938 		prev = k;
939 		k = bkey_p_next(k);
940 		continue;
941 drop_this_key:
942 		next_good_key = k->u64s;
943 
944 		if (!next_good_key ||
945 		    (BSET_BIG_ENDIAN(i) == CPU_BIG_ENDIAN &&
946 		     version >= bcachefs_metadata_version_snapshot)) {
947 			/*
948 			 * only do scanning if bch2_bkey_compat() has nothing to
949 			 * do
950 			 */
951 
952 			if (!bkey_packed_valid(c, b, i, (void *) ((u64 *) k + next_good_key))) {
953 				for (next_good_key = 1;
954 				     next_good_key < (u64 *) vstruct_last(i) - (u64 *) k;
955 				     next_good_key++)
956 					if (bkey_packed_valid(c, b, i, (void *) ((u64 *) k + next_good_key)))
957 						goto got_good_key;
958 			}
959 
960 			/*
961 			 * didn't find a good key, have to truncate the rest of
962 			 * the bset
963 			 */
964 			next_good_key = (u64 *) vstruct_last(i) - (u64 *) k;
965 		}
966 got_good_key:
967 		le16_add_cpu(&i->u64s, -next_good_key);
968 		memmove_u64s_down(k, bkey_p_next(k), (u64 *) vstruct_end(i) - (u64 *) k);
969 	}
970 fsck_err:
971 	printbuf_exit(&buf);
972 	return ret;
973 }
974 
975 int bch2_btree_node_read_done(struct bch_fs *c, struct bch_dev *ca,
976 			      struct btree *b, bool have_retry, bool *saw_error)
977 {
978 	struct btree_node_entry *bne;
979 	struct sort_iter *iter;
980 	struct btree_node *sorted;
981 	struct bkey_packed *k;
982 	struct bset *i;
983 	bool used_mempool, blacklisted;
984 	bool updated_range = b->key.k.type == KEY_TYPE_btree_ptr_v2 &&
985 		BTREE_PTR_RANGE_UPDATED(&bkey_i_to_btree_ptr_v2(&b->key)->v);
986 	unsigned u64s;
987 	unsigned ptr_written = btree_ptr_sectors_written(&b->key);
988 	struct printbuf buf = PRINTBUF;
989 	int ret = 0, retry_read = 0, write = READ;
990 	u64 start_time = local_clock();
991 
992 	b->version_ondisk = U16_MAX;
993 	/* We might get called multiple times on read retry: */
994 	b->written = 0;
995 
996 	iter = mempool_alloc(&c->fill_iter, GFP_NOFS);
997 	sort_iter_init(iter, b, (btree_blocks(c) + 1) * 2);
998 
999 	if (bch2_meta_read_fault("btree"))
1000 		btree_err(-BCH_ERR_btree_node_read_err_must_retry,
1001 			  c, ca, b, NULL,
1002 			  btree_node_fault_injected,
1003 			  "dynamic fault");
1004 
1005 	btree_err_on(le64_to_cpu(b->data->magic) != bset_magic(c),
1006 		     -BCH_ERR_btree_node_read_err_must_retry,
1007 		     c, ca, b, NULL,
1008 		     btree_node_bad_magic,
1009 		     "bad magic: want %llx, got %llx",
1010 		     bset_magic(c), le64_to_cpu(b->data->magic));
1011 
1012 	if (b->key.k.type == KEY_TYPE_btree_ptr_v2) {
1013 		struct bch_btree_ptr_v2 *bp =
1014 			&bkey_i_to_btree_ptr_v2(&b->key)->v;
1015 
1016 		bch2_bpos_to_text(&buf, b->data->min_key);
1017 		prt_str(&buf, "-");
1018 		bch2_bpos_to_text(&buf, b->data->max_key);
1019 
1020 		btree_err_on(b->data->keys.seq != bp->seq,
1021 			     -BCH_ERR_btree_node_read_err_must_retry,
1022 			     c, ca, b, NULL,
1023 			     btree_node_bad_seq,
1024 			     "got wrong btree node (want %llx got %llx)\n"
1025 			     "got btree %s level %llu pos %s",
1026 			     bp->seq, b->data->keys.seq,
1027 			     bch2_btree_id_str(BTREE_NODE_ID(b->data)),
1028 			     BTREE_NODE_LEVEL(b->data),
1029 			     buf.buf);
1030 	} else {
1031 		btree_err_on(!b->data->keys.seq,
1032 			     -BCH_ERR_btree_node_read_err_must_retry,
1033 			     c, ca, b, NULL,
1034 			     btree_node_bad_seq,
1035 			     "bad btree header: seq 0");
1036 	}
1037 
1038 	while (b->written < (ptr_written ?: btree_sectors(c))) {
1039 		unsigned sectors;
1040 		struct nonce nonce;
1041 		bool first = !b->written;
1042 		bool csum_bad;
1043 
1044 		if (!b->written) {
1045 			i = &b->data->keys;
1046 
1047 			btree_err_on(!bch2_checksum_type_valid(c, BSET_CSUM_TYPE(i)),
1048 				     -BCH_ERR_btree_node_read_err_want_retry,
1049 				     c, ca, b, i,
1050 				     bset_unknown_csum,
1051 				     "unknown checksum type %llu", BSET_CSUM_TYPE(i));
1052 
1053 			nonce = btree_nonce(i, b->written << 9);
1054 
1055 			struct bch_csum csum = csum_vstruct(c, BSET_CSUM_TYPE(i), nonce, b->data);
1056 			csum_bad = bch2_crc_cmp(b->data->csum, csum);
1057 			if (csum_bad)
1058 				bch2_io_error(ca, BCH_MEMBER_ERROR_checksum);
1059 
1060 			btree_err_on(csum_bad,
1061 				     -BCH_ERR_btree_node_read_err_want_retry,
1062 				     c, ca, b, i,
1063 				     bset_bad_csum,
1064 				     "%s",
1065 				     (printbuf_reset(&buf),
1066 				      bch2_csum_err_msg(&buf, BSET_CSUM_TYPE(i), b->data->csum, csum),
1067 				      buf.buf));
1068 
1069 			ret = bset_encrypt(c, i, b->written << 9);
1070 			if (bch2_fs_fatal_err_on(ret, c,
1071 					"decrypting btree node: %s", bch2_err_str(ret)))
1072 				goto fsck_err;
1073 
1074 			btree_err_on(btree_node_type_is_extents(btree_node_type(b)) &&
1075 				     !BTREE_NODE_NEW_EXTENT_OVERWRITE(b->data),
1076 				     -BCH_ERR_btree_node_read_err_incompatible,
1077 				     c, NULL, b, NULL,
1078 				     btree_node_unsupported_version,
1079 				     "btree node does not have NEW_EXTENT_OVERWRITE set");
1080 
1081 			sectors = vstruct_sectors(b->data, c->block_bits);
1082 		} else {
1083 			bne = write_block(b);
1084 			i = &bne->keys;
1085 
1086 			if (i->seq != b->data->keys.seq)
1087 				break;
1088 
1089 			btree_err_on(!bch2_checksum_type_valid(c, BSET_CSUM_TYPE(i)),
1090 				     -BCH_ERR_btree_node_read_err_want_retry,
1091 				     c, ca, b, i,
1092 				     bset_unknown_csum,
1093 				     "unknown checksum type %llu", BSET_CSUM_TYPE(i));
1094 
1095 			nonce = btree_nonce(i, b->written << 9);
1096 			struct bch_csum csum = csum_vstruct(c, BSET_CSUM_TYPE(i), nonce, bne);
1097 			csum_bad = bch2_crc_cmp(bne->csum, csum);
1098 			if (csum_bad)
1099 				bch2_io_error(ca, BCH_MEMBER_ERROR_checksum);
1100 
1101 			btree_err_on(csum_bad,
1102 				     -BCH_ERR_btree_node_read_err_want_retry,
1103 				     c, ca, b, i,
1104 				     bset_bad_csum,
1105 				     "%s",
1106 				     (printbuf_reset(&buf),
1107 				      bch2_csum_err_msg(&buf, BSET_CSUM_TYPE(i), bne->csum, csum),
1108 				      buf.buf));
1109 
1110 			ret = bset_encrypt(c, i, b->written << 9);
1111 			if (bch2_fs_fatal_err_on(ret, c,
1112 					"decrypting btree node: %s", bch2_err_str(ret)))
1113 				goto fsck_err;
1114 
1115 			sectors = vstruct_sectors(bne, c->block_bits);
1116 		}
1117 
1118 		b->version_ondisk = min(b->version_ondisk,
1119 					le16_to_cpu(i->version));
1120 
1121 		ret = validate_bset(c, ca, b, i, b->written, sectors,
1122 				    READ, have_retry, saw_error);
1123 		if (ret)
1124 			goto fsck_err;
1125 
1126 		if (!b->written)
1127 			btree_node_set_format(b, b->data->format);
1128 
1129 		ret = validate_bset_keys(c, b, i, READ, have_retry, saw_error);
1130 		if (ret)
1131 			goto fsck_err;
1132 
1133 		SET_BSET_BIG_ENDIAN(i, CPU_BIG_ENDIAN);
1134 
1135 		blacklisted = bch2_journal_seq_is_blacklisted(c,
1136 					le64_to_cpu(i->journal_seq),
1137 					true);
1138 
1139 		btree_err_on(blacklisted && first,
1140 			     -BCH_ERR_btree_node_read_err_fixable,
1141 			     c, ca, b, i,
1142 			     bset_blacklisted_journal_seq,
1143 			     "first btree node bset has blacklisted journal seq (%llu)",
1144 			     le64_to_cpu(i->journal_seq));
1145 
1146 		btree_err_on(blacklisted && ptr_written,
1147 			     -BCH_ERR_btree_node_read_err_fixable,
1148 			     c, ca, b, i,
1149 			     first_bset_blacklisted_journal_seq,
1150 			     "found blacklisted bset (journal seq %llu) in btree node at offset %u-%u/%u",
1151 			     le64_to_cpu(i->journal_seq),
1152 			     b->written, b->written + sectors, ptr_written);
1153 
1154 		b->written += sectors;
1155 
1156 		if (blacklisted && !first)
1157 			continue;
1158 
1159 		sort_iter_add(iter,
1160 			      vstruct_idx(i, 0),
1161 			      vstruct_last(i));
1162 	}
1163 
1164 	if (ptr_written) {
1165 		btree_err_on(b->written < ptr_written,
1166 			     -BCH_ERR_btree_node_read_err_want_retry,
1167 			     c, ca, b, NULL,
1168 			     btree_node_data_missing,
1169 			     "btree node data missing: expected %u sectors, found %u",
1170 			     ptr_written, b->written);
1171 	} else {
1172 		for (bne = write_block(b);
1173 		     bset_byte_offset(b, bne) < btree_buf_bytes(b);
1174 		     bne = (void *) bne + block_bytes(c))
1175 			btree_err_on(bne->keys.seq == b->data->keys.seq &&
1176 				     !bch2_journal_seq_is_blacklisted(c,
1177 								      le64_to_cpu(bne->keys.journal_seq),
1178 								      true),
1179 				     -BCH_ERR_btree_node_read_err_want_retry,
1180 				     c, ca, b, NULL,
1181 				     btree_node_bset_after_end,
1182 				     "found bset signature after last bset");
1183 	}
1184 
1185 	sorted = btree_bounce_alloc(c, btree_buf_bytes(b), &used_mempool);
1186 	sorted->keys.u64s = 0;
1187 
1188 	set_btree_bset(b, b->set, &b->data->keys);
1189 
1190 	b->nr = bch2_key_sort_fix_overlapping(c, &sorted->keys, iter);
1191 
1192 	u64s = le16_to_cpu(sorted->keys.u64s);
1193 	*sorted = *b->data;
1194 	sorted->keys.u64s = cpu_to_le16(u64s);
1195 	swap(sorted, b->data);
1196 	set_btree_bset(b, b->set, &b->data->keys);
1197 	b->nsets = 1;
1198 
1199 	BUG_ON(b->nr.live_u64s != u64s);
1200 
1201 	btree_bounce_free(c, btree_buf_bytes(b), used_mempool, sorted);
1202 
1203 	if (updated_range)
1204 		bch2_btree_node_drop_keys_outside_node(b);
1205 
1206 	i = &b->data->keys;
1207 	for (k = i->start; k != vstruct_last(i);) {
1208 		struct bkey tmp;
1209 		struct bkey_s u = __bkey_disassemble(b, k, &tmp);
1210 
1211 		printbuf_reset(&buf);
1212 
1213 		if (bch2_bkey_val_invalid(c, u.s_c, READ, &buf) ||
1214 		    (bch2_inject_invalid_keys &&
1215 		     !bversion_cmp(u.k->version, MAX_VERSION))) {
1216 			printbuf_reset(&buf);
1217 
1218 			prt_printf(&buf, "invalid bkey: ");
1219 			bch2_bkey_val_invalid(c, u.s_c, READ, &buf);
1220 			prt_printf(&buf, "\n  ");
1221 			bch2_bkey_val_to_text(&buf, c, u.s_c);
1222 
1223 			btree_err(-BCH_ERR_btree_node_read_err_fixable,
1224 				  c, NULL, b, i,
1225 				  btree_node_bad_bkey,
1226 				  "%s", buf.buf);
1227 
1228 			btree_keys_account_key_drop(&b->nr, 0, k);
1229 
1230 			i->u64s = cpu_to_le16(le16_to_cpu(i->u64s) - k->u64s);
1231 			memmove_u64s_down(k, bkey_p_next(k),
1232 					  (u64 *) vstruct_end(i) - (u64 *) k);
1233 			set_btree_bset_end(b, b->set);
1234 			continue;
1235 		}
1236 
1237 		if (u.k->type == KEY_TYPE_btree_ptr_v2) {
1238 			struct bkey_s_btree_ptr_v2 bp = bkey_s_to_btree_ptr_v2(u);
1239 
1240 			bp.v->mem_ptr = 0;
1241 		}
1242 
1243 		k = bkey_p_next(k);
1244 	}
1245 
1246 	bch2_bset_build_aux_tree(b, b->set, false);
1247 
1248 	set_needs_whiteout(btree_bset_first(b), true);
1249 
1250 	btree_node_reset_sib_u64s(b);
1251 
1252 	bkey_for_each_ptr(bch2_bkey_ptrs(bkey_i_to_s(&b->key)), ptr) {
1253 		struct bch_dev *ca2 = bch_dev_bkey_exists(c, ptr->dev);
1254 
1255 		if (ca2->mi.state != BCH_MEMBER_STATE_rw)
1256 			set_btree_node_need_rewrite(b);
1257 	}
1258 
1259 	if (!ptr_written)
1260 		set_btree_node_need_rewrite(b);
1261 out:
1262 	mempool_free(iter, &c->fill_iter);
1263 	printbuf_exit(&buf);
1264 	bch2_time_stats_update(&c->times[BCH_TIME_btree_node_read_done], start_time);
1265 	return retry_read;
1266 fsck_err:
1267 	if (ret == -BCH_ERR_btree_node_read_err_want_retry ||
1268 	    ret == -BCH_ERR_btree_node_read_err_must_retry) {
1269 		retry_read = 1;
1270 	} else {
1271 		set_btree_node_read_error(b);
1272 		bch2_btree_lost_data(c, b->c.btree_id);
1273 	}
1274 	goto out;
1275 }
1276 
1277 static void btree_node_read_work(struct work_struct *work)
1278 {
1279 	struct btree_read_bio *rb =
1280 		container_of(work, struct btree_read_bio, work);
1281 	struct bch_fs *c	= rb->c;
1282 	struct btree *b		= rb->b;
1283 	struct bch_dev *ca	= bch_dev_bkey_exists(c, rb->pick.ptr.dev);
1284 	struct bio *bio		= &rb->bio;
1285 	struct bch_io_failures failed = { .nr = 0 };
1286 	struct printbuf buf = PRINTBUF;
1287 	bool saw_error = false;
1288 	bool retry = false;
1289 	bool can_retry;
1290 
1291 	goto start;
1292 	while (1) {
1293 		retry = true;
1294 		bch_info(c, "retrying read");
1295 		ca = bch_dev_bkey_exists(c, rb->pick.ptr.dev);
1296 		rb->have_ioref		= bch2_dev_get_ioref(ca, READ);
1297 		bio_reset(bio, NULL, REQ_OP_READ|REQ_SYNC|REQ_META);
1298 		bio->bi_iter.bi_sector	= rb->pick.ptr.offset;
1299 		bio->bi_iter.bi_size	= btree_buf_bytes(b);
1300 
1301 		if (rb->have_ioref) {
1302 			bio_set_dev(bio, ca->disk_sb.bdev);
1303 			submit_bio_wait(bio);
1304 		} else {
1305 			bio->bi_status = BLK_STS_REMOVED;
1306 		}
1307 start:
1308 		printbuf_reset(&buf);
1309 		bch2_btree_pos_to_text(&buf, c, b);
1310 		bch2_dev_io_err_on(bio->bi_status, ca, BCH_MEMBER_ERROR_read,
1311 				   "btree read error %s for %s",
1312 				   bch2_blk_status_to_str(bio->bi_status), buf.buf);
1313 		if (rb->have_ioref)
1314 			percpu_ref_put(&ca->io_ref);
1315 		rb->have_ioref = false;
1316 
1317 		bch2_mark_io_failure(&failed, &rb->pick);
1318 
1319 		can_retry = bch2_bkey_pick_read_device(c,
1320 				bkey_i_to_s_c(&b->key),
1321 				&failed, &rb->pick) > 0;
1322 
1323 		if (!bio->bi_status &&
1324 		    !bch2_btree_node_read_done(c, ca, b, can_retry, &saw_error)) {
1325 			if (retry)
1326 				bch_info(c, "retry success");
1327 			break;
1328 		}
1329 
1330 		saw_error = true;
1331 
1332 		if (!can_retry) {
1333 			set_btree_node_read_error(b);
1334 			bch2_btree_lost_data(c, b->c.btree_id);
1335 			break;
1336 		}
1337 	}
1338 
1339 	bch2_time_stats_update(&c->times[BCH_TIME_btree_node_read],
1340 			       rb->start_time);
1341 	bio_put(&rb->bio);
1342 
1343 	if (saw_error &&
1344 	    !btree_node_read_error(b) &&
1345 	    c->curr_recovery_pass != BCH_RECOVERY_PASS_scan_for_btree_nodes) {
1346 		printbuf_reset(&buf);
1347 		bch2_bpos_to_text(&buf, b->key.k.p);
1348 		bch_err_ratelimited(c, "%s: rewriting btree node at btree=%s level=%u %s due to error",
1349 			 __func__, bch2_btree_id_str(b->c.btree_id), b->c.level, buf.buf);
1350 
1351 		bch2_btree_node_rewrite_async(c, b);
1352 	}
1353 
1354 	printbuf_exit(&buf);
1355 	clear_btree_node_read_in_flight(b);
1356 	wake_up_bit(&b->flags, BTREE_NODE_read_in_flight);
1357 }
1358 
1359 static void btree_node_read_endio(struct bio *bio)
1360 {
1361 	struct btree_read_bio *rb =
1362 		container_of(bio, struct btree_read_bio, bio);
1363 	struct bch_fs *c	= rb->c;
1364 
1365 	if (rb->have_ioref) {
1366 		struct bch_dev *ca = bch_dev_bkey_exists(c, rb->pick.ptr.dev);
1367 
1368 		bch2_latency_acct(ca, rb->start_time, READ);
1369 	}
1370 
1371 	queue_work(c->io_complete_wq, &rb->work);
1372 }
1373 
1374 struct btree_node_read_all {
1375 	struct closure		cl;
1376 	struct bch_fs		*c;
1377 	struct btree		*b;
1378 	unsigned		nr;
1379 	void			*buf[BCH_REPLICAS_MAX];
1380 	struct bio		*bio[BCH_REPLICAS_MAX];
1381 	blk_status_t		err[BCH_REPLICAS_MAX];
1382 };
1383 
1384 static unsigned btree_node_sectors_written(struct bch_fs *c, void *data)
1385 {
1386 	struct btree_node *bn = data;
1387 	struct btree_node_entry *bne;
1388 	unsigned offset = 0;
1389 
1390 	if (le64_to_cpu(bn->magic) !=  bset_magic(c))
1391 		return 0;
1392 
1393 	while (offset < btree_sectors(c)) {
1394 		if (!offset) {
1395 			offset += vstruct_sectors(bn, c->block_bits);
1396 		} else {
1397 			bne = data + (offset << 9);
1398 			if (bne->keys.seq != bn->keys.seq)
1399 				break;
1400 			offset += vstruct_sectors(bne, c->block_bits);
1401 		}
1402 	}
1403 
1404 	return offset;
1405 }
1406 
1407 static bool btree_node_has_extra_bsets(struct bch_fs *c, unsigned offset, void *data)
1408 {
1409 	struct btree_node *bn = data;
1410 	struct btree_node_entry *bne;
1411 
1412 	if (!offset)
1413 		return false;
1414 
1415 	while (offset < btree_sectors(c)) {
1416 		bne = data + (offset << 9);
1417 		if (bne->keys.seq == bn->keys.seq)
1418 			return true;
1419 		offset++;
1420 	}
1421 
1422 	return false;
1423 	return offset;
1424 }
1425 
1426 static CLOSURE_CALLBACK(btree_node_read_all_replicas_done)
1427 {
1428 	closure_type(ra, struct btree_node_read_all, cl);
1429 	struct bch_fs *c = ra->c;
1430 	struct btree *b = ra->b;
1431 	struct printbuf buf = PRINTBUF;
1432 	bool dump_bset_maps = false;
1433 	bool have_retry = false;
1434 	int ret = 0, best = -1, write = READ;
1435 	unsigned i, written = 0, written2 = 0;
1436 	__le64 seq = b->key.k.type == KEY_TYPE_btree_ptr_v2
1437 		? bkey_i_to_btree_ptr_v2(&b->key)->v.seq : 0;
1438 	bool _saw_error = false, *saw_error = &_saw_error;
1439 
1440 	for (i = 0; i < ra->nr; i++) {
1441 		struct btree_node *bn = ra->buf[i];
1442 
1443 		if (ra->err[i])
1444 			continue;
1445 
1446 		if (le64_to_cpu(bn->magic) != bset_magic(c) ||
1447 		    (seq && seq != bn->keys.seq))
1448 			continue;
1449 
1450 		if (best < 0) {
1451 			best = i;
1452 			written = btree_node_sectors_written(c, bn);
1453 			continue;
1454 		}
1455 
1456 		written2 = btree_node_sectors_written(c, ra->buf[i]);
1457 		if (btree_err_on(written2 != written, -BCH_ERR_btree_node_read_err_fixable,
1458 				 c, NULL, b, NULL,
1459 				 btree_node_replicas_sectors_written_mismatch,
1460 				 "btree node sectors written mismatch: %u != %u",
1461 				 written, written2) ||
1462 		    btree_err_on(btree_node_has_extra_bsets(c, written2, ra->buf[i]),
1463 				 -BCH_ERR_btree_node_read_err_fixable,
1464 				 c, NULL, b, NULL,
1465 				 btree_node_bset_after_end,
1466 				 "found bset signature after last bset") ||
1467 		    btree_err_on(memcmp(ra->buf[best], ra->buf[i], written << 9),
1468 				 -BCH_ERR_btree_node_read_err_fixable,
1469 				 c, NULL, b, NULL,
1470 				 btree_node_replicas_data_mismatch,
1471 				 "btree node replicas content mismatch"))
1472 			dump_bset_maps = true;
1473 
1474 		if (written2 > written) {
1475 			written = written2;
1476 			best = i;
1477 		}
1478 	}
1479 fsck_err:
1480 	if (dump_bset_maps) {
1481 		for (i = 0; i < ra->nr; i++) {
1482 			struct btree_node *bn = ra->buf[i];
1483 			struct btree_node_entry *bne = NULL;
1484 			unsigned offset = 0, sectors;
1485 			bool gap = false;
1486 
1487 			if (ra->err[i])
1488 				continue;
1489 
1490 			printbuf_reset(&buf);
1491 
1492 			while (offset < btree_sectors(c)) {
1493 				if (!offset) {
1494 					sectors = vstruct_sectors(bn, c->block_bits);
1495 				} else {
1496 					bne = ra->buf[i] + (offset << 9);
1497 					if (bne->keys.seq != bn->keys.seq)
1498 						break;
1499 					sectors = vstruct_sectors(bne, c->block_bits);
1500 				}
1501 
1502 				prt_printf(&buf, " %u-%u", offset, offset + sectors);
1503 				if (bne && bch2_journal_seq_is_blacklisted(c,
1504 							le64_to_cpu(bne->keys.journal_seq), false))
1505 					prt_printf(&buf, "*");
1506 				offset += sectors;
1507 			}
1508 
1509 			while (offset < btree_sectors(c)) {
1510 				bne = ra->buf[i] + (offset << 9);
1511 				if (bne->keys.seq == bn->keys.seq) {
1512 					if (!gap)
1513 						prt_printf(&buf, " GAP");
1514 					gap = true;
1515 
1516 					sectors = vstruct_sectors(bne, c->block_bits);
1517 					prt_printf(&buf, " %u-%u", offset, offset + sectors);
1518 					if (bch2_journal_seq_is_blacklisted(c,
1519 							le64_to_cpu(bne->keys.journal_seq), false))
1520 						prt_printf(&buf, "*");
1521 				}
1522 				offset++;
1523 			}
1524 
1525 			bch_err(c, "replica %u:%s", i, buf.buf);
1526 		}
1527 	}
1528 
1529 	if (best >= 0) {
1530 		memcpy(b->data, ra->buf[best], btree_buf_bytes(b));
1531 		ret = bch2_btree_node_read_done(c, NULL, b, false, saw_error);
1532 	} else {
1533 		ret = -1;
1534 	}
1535 
1536 	if (ret) {
1537 		set_btree_node_read_error(b);
1538 		bch2_btree_lost_data(c, b->c.btree_id);
1539 	} else if (*saw_error)
1540 		bch2_btree_node_rewrite_async(c, b);
1541 
1542 	for (i = 0; i < ra->nr; i++) {
1543 		mempool_free(ra->buf[i], &c->btree_bounce_pool);
1544 		bio_put(ra->bio[i]);
1545 	}
1546 
1547 	closure_debug_destroy(&ra->cl);
1548 	kfree(ra);
1549 	printbuf_exit(&buf);
1550 
1551 	clear_btree_node_read_in_flight(b);
1552 	wake_up_bit(&b->flags, BTREE_NODE_read_in_flight);
1553 }
1554 
1555 static void btree_node_read_all_replicas_endio(struct bio *bio)
1556 {
1557 	struct btree_read_bio *rb =
1558 		container_of(bio, struct btree_read_bio, bio);
1559 	struct bch_fs *c	= rb->c;
1560 	struct btree_node_read_all *ra = rb->ra;
1561 
1562 	if (rb->have_ioref) {
1563 		struct bch_dev *ca = bch_dev_bkey_exists(c, rb->pick.ptr.dev);
1564 
1565 		bch2_latency_acct(ca, rb->start_time, READ);
1566 	}
1567 
1568 	ra->err[rb->idx] = bio->bi_status;
1569 	closure_put(&ra->cl);
1570 }
1571 
1572 /*
1573  * XXX This allocates multiple times from the same mempools, and can deadlock
1574  * under sufficient memory pressure (but is only a debug path)
1575  */
1576 static int btree_node_read_all_replicas(struct bch_fs *c, struct btree *b, bool sync)
1577 {
1578 	struct bkey_s_c k = bkey_i_to_s_c(&b->key);
1579 	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
1580 	const union bch_extent_entry *entry;
1581 	struct extent_ptr_decoded pick;
1582 	struct btree_node_read_all *ra;
1583 	unsigned i;
1584 
1585 	ra = kzalloc(sizeof(*ra), GFP_NOFS);
1586 	if (!ra)
1587 		return -BCH_ERR_ENOMEM_btree_node_read_all_replicas;
1588 
1589 	closure_init(&ra->cl, NULL);
1590 	ra->c	= c;
1591 	ra->b	= b;
1592 	ra->nr	= bch2_bkey_nr_ptrs(k);
1593 
1594 	for (i = 0; i < ra->nr; i++) {
1595 		ra->buf[i] = mempool_alloc(&c->btree_bounce_pool, GFP_NOFS);
1596 		ra->bio[i] = bio_alloc_bioset(NULL,
1597 					      buf_pages(ra->buf[i], btree_buf_bytes(b)),
1598 					      REQ_OP_READ|REQ_SYNC|REQ_META,
1599 					      GFP_NOFS,
1600 					      &c->btree_bio);
1601 	}
1602 
1603 	i = 0;
1604 	bkey_for_each_ptr_decode(k.k, ptrs, pick, entry) {
1605 		struct bch_dev *ca = bch_dev_bkey_exists(c, pick.ptr.dev);
1606 		struct btree_read_bio *rb =
1607 			container_of(ra->bio[i], struct btree_read_bio, bio);
1608 		rb->c			= c;
1609 		rb->b			= b;
1610 		rb->ra			= ra;
1611 		rb->start_time		= local_clock();
1612 		rb->have_ioref		= bch2_dev_get_ioref(ca, READ);
1613 		rb->idx			= i;
1614 		rb->pick		= pick;
1615 		rb->bio.bi_iter.bi_sector = pick.ptr.offset;
1616 		rb->bio.bi_end_io	= btree_node_read_all_replicas_endio;
1617 		bch2_bio_map(&rb->bio, ra->buf[i], btree_buf_bytes(b));
1618 
1619 		if (rb->have_ioref) {
1620 			this_cpu_add(ca->io_done->sectors[READ][BCH_DATA_btree],
1621 				     bio_sectors(&rb->bio));
1622 			bio_set_dev(&rb->bio, ca->disk_sb.bdev);
1623 
1624 			closure_get(&ra->cl);
1625 			submit_bio(&rb->bio);
1626 		} else {
1627 			ra->err[i] = BLK_STS_REMOVED;
1628 		}
1629 
1630 		i++;
1631 	}
1632 
1633 	if (sync) {
1634 		closure_sync(&ra->cl);
1635 		btree_node_read_all_replicas_done(&ra->cl.work);
1636 	} else {
1637 		continue_at(&ra->cl, btree_node_read_all_replicas_done,
1638 			    c->io_complete_wq);
1639 	}
1640 
1641 	return 0;
1642 }
1643 
1644 void bch2_btree_node_read(struct btree_trans *trans, struct btree *b,
1645 			  bool sync)
1646 {
1647 	struct bch_fs *c = trans->c;
1648 	struct extent_ptr_decoded pick;
1649 	struct btree_read_bio *rb;
1650 	struct bch_dev *ca;
1651 	struct bio *bio;
1652 	int ret;
1653 
1654 	trace_and_count(c, btree_node_read, trans, b);
1655 
1656 	if (bch2_verify_all_btree_replicas &&
1657 	    !btree_node_read_all_replicas(c, b, sync))
1658 		return;
1659 
1660 	ret = bch2_bkey_pick_read_device(c, bkey_i_to_s_c(&b->key),
1661 					 NULL, &pick);
1662 
1663 	if (ret <= 0) {
1664 		struct printbuf buf = PRINTBUF;
1665 
1666 		prt_str(&buf, "btree node read error: no device to read from\n at ");
1667 		bch2_btree_pos_to_text(&buf, c, b);
1668 		bch_err_ratelimited(c, "%s", buf.buf);
1669 
1670 		if (c->recovery_passes_explicit & BIT_ULL(BCH_RECOVERY_PASS_check_topology) &&
1671 		    c->curr_recovery_pass > BCH_RECOVERY_PASS_check_topology)
1672 			bch2_fatal_error(c);
1673 
1674 		set_btree_node_read_error(b);
1675 		bch2_btree_lost_data(c, b->c.btree_id);
1676 		clear_btree_node_read_in_flight(b);
1677 		wake_up_bit(&b->flags, BTREE_NODE_read_in_flight);
1678 		printbuf_exit(&buf);
1679 		return;
1680 	}
1681 
1682 	ca = bch_dev_bkey_exists(c, pick.ptr.dev);
1683 
1684 	bio = bio_alloc_bioset(NULL,
1685 			       buf_pages(b->data, btree_buf_bytes(b)),
1686 			       REQ_OP_READ|REQ_SYNC|REQ_META,
1687 			       GFP_NOFS,
1688 			       &c->btree_bio);
1689 	rb = container_of(bio, struct btree_read_bio, bio);
1690 	rb->c			= c;
1691 	rb->b			= b;
1692 	rb->ra			= NULL;
1693 	rb->start_time		= local_clock();
1694 	rb->have_ioref		= bch2_dev_get_ioref(ca, READ);
1695 	rb->pick		= pick;
1696 	INIT_WORK(&rb->work, btree_node_read_work);
1697 	bio->bi_iter.bi_sector	= pick.ptr.offset;
1698 	bio->bi_end_io		= btree_node_read_endio;
1699 	bch2_bio_map(bio, b->data, btree_buf_bytes(b));
1700 
1701 	if (rb->have_ioref) {
1702 		this_cpu_add(ca->io_done->sectors[READ][BCH_DATA_btree],
1703 			     bio_sectors(bio));
1704 		bio_set_dev(bio, ca->disk_sb.bdev);
1705 
1706 		if (sync) {
1707 			submit_bio_wait(bio);
1708 			bch2_latency_acct(ca, rb->start_time, READ);
1709 			btree_node_read_work(&rb->work);
1710 		} else {
1711 			submit_bio(bio);
1712 		}
1713 	} else {
1714 		bio->bi_status = BLK_STS_REMOVED;
1715 
1716 		if (sync)
1717 			btree_node_read_work(&rb->work);
1718 		else
1719 			queue_work(c->io_complete_wq, &rb->work);
1720 	}
1721 }
1722 
1723 static int __bch2_btree_root_read(struct btree_trans *trans, enum btree_id id,
1724 				  const struct bkey_i *k, unsigned level)
1725 {
1726 	struct bch_fs *c = trans->c;
1727 	struct closure cl;
1728 	struct btree *b;
1729 	int ret;
1730 
1731 	closure_init_stack(&cl);
1732 
1733 	do {
1734 		ret = bch2_btree_cache_cannibalize_lock(trans, &cl);
1735 		closure_sync(&cl);
1736 	} while (ret);
1737 
1738 	b = bch2_btree_node_mem_alloc(trans, level != 0);
1739 	bch2_btree_cache_cannibalize_unlock(trans);
1740 
1741 	BUG_ON(IS_ERR(b));
1742 
1743 	bkey_copy(&b->key, k);
1744 	BUG_ON(bch2_btree_node_hash_insert(&c->btree_cache, b, level, id));
1745 
1746 	set_btree_node_read_in_flight(b);
1747 
1748 	bch2_btree_node_read(trans, b, true);
1749 
1750 	if (btree_node_read_error(b)) {
1751 		bch2_btree_node_hash_remove(&c->btree_cache, b);
1752 
1753 		mutex_lock(&c->btree_cache.lock);
1754 		list_move(&b->list, &c->btree_cache.freeable);
1755 		mutex_unlock(&c->btree_cache.lock);
1756 
1757 		ret = -BCH_ERR_btree_node_read_error;
1758 		goto err;
1759 	}
1760 
1761 	bch2_btree_set_root_for_read(c, b);
1762 err:
1763 	six_unlock_write(&b->c.lock);
1764 	six_unlock_intent(&b->c.lock);
1765 
1766 	return ret;
1767 }
1768 
1769 int bch2_btree_root_read(struct bch_fs *c, enum btree_id id,
1770 			const struct bkey_i *k, unsigned level)
1771 {
1772 	return bch2_trans_run(c, __bch2_btree_root_read(trans, id, k, level));
1773 }
1774 
1775 static void bch2_btree_complete_write(struct bch_fs *c, struct btree *b,
1776 				      struct btree_write *w)
1777 {
1778 	unsigned long old, new, v = READ_ONCE(b->will_make_reachable);
1779 
1780 	do {
1781 		old = new = v;
1782 		if (!(old & 1))
1783 			break;
1784 
1785 		new &= ~1UL;
1786 	} while ((v = cmpxchg(&b->will_make_reachable, old, new)) != old);
1787 
1788 	if (old & 1)
1789 		closure_put(&((struct btree_update *) new)->cl);
1790 
1791 	bch2_journal_pin_drop(&c->journal, &w->journal);
1792 }
1793 
1794 static void __btree_node_write_done(struct bch_fs *c, struct btree *b)
1795 {
1796 	struct btree_write *w = btree_prev_write(b);
1797 	unsigned long old, new, v;
1798 	unsigned type = 0;
1799 
1800 	bch2_btree_complete_write(c, b, w);
1801 
1802 	v = READ_ONCE(b->flags);
1803 	do {
1804 		old = new = v;
1805 
1806 		if ((old & (1U << BTREE_NODE_dirty)) &&
1807 		    (old & (1U << BTREE_NODE_need_write)) &&
1808 		    !(old & (1U << BTREE_NODE_never_write)) &&
1809 		    !(old & (1U << BTREE_NODE_write_blocked)) &&
1810 		    !(old & (1U << BTREE_NODE_will_make_reachable))) {
1811 			new &= ~(1U << BTREE_NODE_dirty);
1812 			new &= ~(1U << BTREE_NODE_need_write);
1813 			new |=  (1U << BTREE_NODE_write_in_flight);
1814 			new |=  (1U << BTREE_NODE_write_in_flight_inner);
1815 			new |=  (1U << BTREE_NODE_just_written);
1816 			new ^=  (1U << BTREE_NODE_write_idx);
1817 
1818 			type = new & BTREE_WRITE_TYPE_MASK;
1819 			new &= ~BTREE_WRITE_TYPE_MASK;
1820 		} else {
1821 			new &= ~(1U << BTREE_NODE_write_in_flight);
1822 			new &= ~(1U << BTREE_NODE_write_in_flight_inner);
1823 		}
1824 	} while ((v = cmpxchg(&b->flags, old, new)) != old);
1825 
1826 	if (new & (1U << BTREE_NODE_write_in_flight))
1827 		__bch2_btree_node_write(c, b, BTREE_WRITE_ALREADY_STARTED|type);
1828 	else
1829 		wake_up_bit(&b->flags, BTREE_NODE_write_in_flight);
1830 }
1831 
1832 static void btree_node_write_done(struct bch_fs *c, struct btree *b)
1833 {
1834 	struct btree_trans *trans = bch2_trans_get(c);
1835 
1836 	btree_node_lock_nopath_nofail(trans, &b->c, SIX_LOCK_read);
1837 	__btree_node_write_done(c, b);
1838 	six_unlock_read(&b->c.lock);
1839 
1840 	bch2_trans_put(trans);
1841 }
1842 
1843 static void btree_node_write_work(struct work_struct *work)
1844 {
1845 	struct btree_write_bio *wbio =
1846 		container_of(work, struct btree_write_bio, work);
1847 	struct bch_fs *c	= wbio->wbio.c;
1848 	struct btree *b		= wbio->wbio.bio.bi_private;
1849 	struct bch_extent_ptr *ptr;
1850 	int ret = 0;
1851 
1852 	btree_bounce_free(c,
1853 		wbio->data_bytes,
1854 		wbio->wbio.used_mempool,
1855 		wbio->data);
1856 
1857 	bch2_bkey_drop_ptrs(bkey_i_to_s(&wbio->key), ptr,
1858 		bch2_dev_list_has_dev(wbio->wbio.failed, ptr->dev));
1859 
1860 	if (!bch2_bkey_nr_ptrs(bkey_i_to_s_c(&wbio->key))) {
1861 		ret = -BCH_ERR_btree_node_write_all_failed;
1862 		goto err;
1863 	}
1864 
1865 	if (wbio->wbio.first_btree_write) {
1866 		if (wbio->wbio.failed.nr) {
1867 
1868 		}
1869 	} else {
1870 		ret = bch2_trans_do(c, NULL, NULL, 0,
1871 			bch2_btree_node_update_key_get_iter(trans, b, &wbio->key,
1872 					BCH_WATERMARK_interior_updates|
1873 					BCH_TRANS_COMMIT_journal_reclaim|
1874 					BCH_TRANS_COMMIT_no_enospc|
1875 					BCH_TRANS_COMMIT_no_check_rw,
1876 					!wbio->wbio.failed.nr));
1877 		if (ret)
1878 			goto err;
1879 	}
1880 out:
1881 	bio_put(&wbio->wbio.bio);
1882 	btree_node_write_done(c, b);
1883 	return;
1884 err:
1885 	set_btree_node_noevict(b);
1886 	bch2_fs_fatal_err_on(!bch2_err_matches(ret, EROFS), c,
1887 			     "writing btree node: %s", bch2_err_str(ret));
1888 	goto out;
1889 }
1890 
1891 static void btree_node_write_endio(struct bio *bio)
1892 {
1893 	struct bch_write_bio *wbio	= to_wbio(bio);
1894 	struct bch_write_bio *parent	= wbio->split ? wbio->parent : NULL;
1895 	struct bch_write_bio *orig	= parent ?: wbio;
1896 	struct btree_write_bio *wb	= container_of(orig, struct btree_write_bio, wbio);
1897 	struct bch_fs *c		= wbio->c;
1898 	struct btree *b			= wbio->bio.bi_private;
1899 	struct bch_dev *ca		= bch_dev_bkey_exists(c, wbio->dev);
1900 	unsigned long flags;
1901 
1902 	if (wbio->have_ioref)
1903 		bch2_latency_acct(ca, wbio->submit_time, WRITE);
1904 
1905 	if (bch2_dev_io_err_on(bio->bi_status, ca, BCH_MEMBER_ERROR_write,
1906 			       "btree write error: %s",
1907 			       bch2_blk_status_to_str(bio->bi_status)) ||
1908 	    bch2_meta_write_fault("btree")) {
1909 		spin_lock_irqsave(&c->btree_write_error_lock, flags);
1910 		bch2_dev_list_add_dev(&orig->failed, wbio->dev);
1911 		spin_unlock_irqrestore(&c->btree_write_error_lock, flags);
1912 	}
1913 
1914 	if (wbio->have_ioref)
1915 		percpu_ref_put(&ca->io_ref);
1916 
1917 	if (parent) {
1918 		bio_put(bio);
1919 		bio_endio(&parent->bio);
1920 		return;
1921 	}
1922 
1923 	clear_btree_node_write_in_flight_inner(b);
1924 	wake_up_bit(&b->flags, BTREE_NODE_write_in_flight_inner);
1925 	INIT_WORK(&wb->work, btree_node_write_work);
1926 	queue_work(c->btree_io_complete_wq, &wb->work);
1927 }
1928 
1929 static int validate_bset_for_write(struct bch_fs *c, struct btree *b,
1930 				   struct bset *i, unsigned sectors)
1931 {
1932 	struct printbuf buf = PRINTBUF;
1933 	bool saw_error;
1934 	int ret;
1935 
1936 	ret = bch2_bkey_invalid(c, bkey_i_to_s_c(&b->key),
1937 				BKEY_TYPE_btree, WRITE, &buf);
1938 
1939 	if (ret)
1940 		bch2_fs_inconsistent(c, "invalid btree node key before write: %s", buf.buf);
1941 	printbuf_exit(&buf);
1942 	if (ret)
1943 		return ret;
1944 
1945 	ret = validate_bset_keys(c, b, i, WRITE, false, &saw_error) ?:
1946 		validate_bset(c, NULL, b, i, b->written, sectors, WRITE, false, &saw_error);
1947 	if (ret) {
1948 		bch2_inconsistent_error(c);
1949 		dump_stack();
1950 	}
1951 
1952 	return ret;
1953 }
1954 
1955 static void btree_write_submit(struct work_struct *work)
1956 {
1957 	struct btree_write_bio *wbio = container_of(work, struct btree_write_bio, work);
1958 	BKEY_PADDED_ONSTACK(k, BKEY_BTREE_PTR_VAL_U64s_MAX) tmp;
1959 
1960 	bkey_copy(&tmp.k, &wbio->key);
1961 
1962 	bkey_for_each_ptr(bch2_bkey_ptrs(bkey_i_to_s(&tmp.k)), ptr)
1963 		ptr->offset += wbio->sector_offset;
1964 
1965 	bch2_submit_wbio_replicas(&wbio->wbio, wbio->wbio.c, BCH_DATA_btree,
1966 				  &tmp.k, false);
1967 }
1968 
1969 void __bch2_btree_node_write(struct bch_fs *c, struct btree *b, unsigned flags)
1970 {
1971 	struct btree_write_bio *wbio;
1972 	struct bset_tree *t;
1973 	struct bset *i;
1974 	struct btree_node *bn = NULL;
1975 	struct btree_node_entry *bne = NULL;
1976 	struct sort_iter_stack sort_iter;
1977 	struct nonce nonce;
1978 	unsigned bytes_to_write, sectors_to_write, bytes, u64s;
1979 	u64 seq = 0;
1980 	bool used_mempool;
1981 	unsigned long old, new;
1982 	bool validate_before_checksum = false;
1983 	enum btree_write_type type = flags & BTREE_WRITE_TYPE_MASK;
1984 	void *data;
1985 	int ret;
1986 
1987 	if (flags & BTREE_WRITE_ALREADY_STARTED)
1988 		goto do_write;
1989 
1990 	/*
1991 	 * We may only have a read lock on the btree node - the dirty bit is our
1992 	 * "lock" against racing with other threads that may be trying to start
1993 	 * a write, we do a write iff we clear the dirty bit. Since setting the
1994 	 * dirty bit requires a write lock, we can't race with other threads
1995 	 * redirtying it:
1996 	 */
1997 	do {
1998 		old = new = READ_ONCE(b->flags);
1999 
2000 		if (!(old & (1 << BTREE_NODE_dirty)))
2001 			return;
2002 
2003 		if ((flags & BTREE_WRITE_ONLY_IF_NEED) &&
2004 		    !(old & (1 << BTREE_NODE_need_write)))
2005 			return;
2006 
2007 		if (old &
2008 		    ((1 << BTREE_NODE_never_write)|
2009 		     (1 << BTREE_NODE_write_blocked)))
2010 			return;
2011 
2012 		if (b->written &&
2013 		    (old & (1 << BTREE_NODE_will_make_reachable)))
2014 			return;
2015 
2016 		if (old & (1 << BTREE_NODE_write_in_flight))
2017 			return;
2018 
2019 		if (flags & BTREE_WRITE_ONLY_IF_NEED)
2020 			type = new & BTREE_WRITE_TYPE_MASK;
2021 		new &= ~BTREE_WRITE_TYPE_MASK;
2022 
2023 		new &= ~(1 << BTREE_NODE_dirty);
2024 		new &= ~(1 << BTREE_NODE_need_write);
2025 		new |=  (1 << BTREE_NODE_write_in_flight);
2026 		new |=  (1 << BTREE_NODE_write_in_flight_inner);
2027 		new |=  (1 << BTREE_NODE_just_written);
2028 		new ^=  (1 << BTREE_NODE_write_idx);
2029 	} while (cmpxchg_acquire(&b->flags, old, new) != old);
2030 
2031 	if (new & (1U << BTREE_NODE_need_write))
2032 		return;
2033 do_write:
2034 	BUG_ON((type == BTREE_WRITE_initial) != (b->written == 0));
2035 
2036 	atomic_dec(&c->btree_cache.dirty);
2037 
2038 	BUG_ON(btree_node_fake(b));
2039 	BUG_ON((b->will_make_reachable != 0) != !b->written);
2040 
2041 	BUG_ON(b->written >= btree_sectors(c));
2042 	BUG_ON(b->written & (block_sectors(c) - 1));
2043 	BUG_ON(bset_written(b, btree_bset_last(b)));
2044 	BUG_ON(le64_to_cpu(b->data->magic) != bset_magic(c));
2045 	BUG_ON(memcmp(&b->data->format, &b->format, sizeof(b->format)));
2046 
2047 	bch2_sort_whiteouts(c, b);
2048 
2049 	sort_iter_stack_init(&sort_iter, b);
2050 
2051 	bytes = !b->written
2052 		? sizeof(struct btree_node)
2053 		: sizeof(struct btree_node_entry);
2054 
2055 	bytes += b->whiteout_u64s * sizeof(u64);
2056 
2057 	for_each_bset(b, t) {
2058 		i = bset(b, t);
2059 
2060 		if (bset_written(b, i))
2061 			continue;
2062 
2063 		bytes += le16_to_cpu(i->u64s) * sizeof(u64);
2064 		sort_iter_add(&sort_iter.iter,
2065 			      btree_bkey_first(b, t),
2066 			      btree_bkey_last(b, t));
2067 		seq = max(seq, le64_to_cpu(i->journal_seq));
2068 	}
2069 
2070 	BUG_ON(b->written && !seq);
2071 
2072 	/* bch2_varint_decode may read up to 7 bytes past the end of the buffer: */
2073 	bytes += 8;
2074 
2075 	/* buffer must be a multiple of the block size */
2076 	bytes = round_up(bytes, block_bytes(c));
2077 
2078 	data = btree_bounce_alloc(c, bytes, &used_mempool);
2079 
2080 	if (!b->written) {
2081 		bn = data;
2082 		*bn = *b->data;
2083 		i = &bn->keys;
2084 	} else {
2085 		bne = data;
2086 		bne->keys = b->data->keys;
2087 		i = &bne->keys;
2088 	}
2089 
2090 	i->journal_seq	= cpu_to_le64(seq);
2091 	i->u64s		= 0;
2092 
2093 	sort_iter_add(&sort_iter.iter,
2094 		      unwritten_whiteouts_start(b),
2095 		      unwritten_whiteouts_end(b));
2096 	SET_BSET_SEPARATE_WHITEOUTS(i, false);
2097 
2098 	b->whiteout_u64s = 0;
2099 
2100 	u64s = bch2_sort_keys(i->start, &sort_iter.iter, false);
2101 	le16_add_cpu(&i->u64s, u64s);
2102 
2103 	BUG_ON(!b->written && i->u64s != b->data->keys.u64s);
2104 
2105 	set_needs_whiteout(i, false);
2106 
2107 	/* do we have data to write? */
2108 	if (b->written && !i->u64s)
2109 		goto nowrite;
2110 
2111 	bytes_to_write = vstruct_end(i) - data;
2112 	sectors_to_write = round_up(bytes_to_write, block_bytes(c)) >> 9;
2113 
2114 	if (!b->written &&
2115 	    b->key.k.type == KEY_TYPE_btree_ptr_v2)
2116 		BUG_ON(btree_ptr_sectors_written(&b->key) != sectors_to_write);
2117 
2118 	memset(data + bytes_to_write, 0,
2119 	       (sectors_to_write << 9) - bytes_to_write);
2120 
2121 	BUG_ON(b->written + sectors_to_write > btree_sectors(c));
2122 	BUG_ON(BSET_BIG_ENDIAN(i) != CPU_BIG_ENDIAN);
2123 	BUG_ON(i->seq != b->data->keys.seq);
2124 
2125 	i->version = cpu_to_le16(c->sb.version);
2126 	SET_BSET_OFFSET(i, b->written);
2127 	SET_BSET_CSUM_TYPE(i, bch2_meta_checksum_type(c));
2128 
2129 	if (bch2_csum_type_is_encryption(BSET_CSUM_TYPE(i)))
2130 		validate_before_checksum = true;
2131 
2132 	/* validate_bset will be modifying: */
2133 	if (le16_to_cpu(i->version) < bcachefs_metadata_version_current)
2134 		validate_before_checksum = true;
2135 
2136 	/* if we're going to be encrypting, check metadata validity first: */
2137 	if (validate_before_checksum &&
2138 	    validate_bset_for_write(c, b, i, sectors_to_write))
2139 		goto err;
2140 
2141 	ret = bset_encrypt(c, i, b->written << 9);
2142 	if (bch2_fs_fatal_err_on(ret, c,
2143 			"encrypting btree node: %s", bch2_err_str(ret)))
2144 		goto err;
2145 
2146 	nonce = btree_nonce(i, b->written << 9);
2147 
2148 	if (bn)
2149 		bn->csum = csum_vstruct(c, BSET_CSUM_TYPE(i), nonce, bn);
2150 	else
2151 		bne->csum = csum_vstruct(c, BSET_CSUM_TYPE(i), nonce, bne);
2152 
2153 	/* if we're not encrypting, check metadata after checksumming: */
2154 	if (!validate_before_checksum &&
2155 	    validate_bset_for_write(c, b, i, sectors_to_write))
2156 		goto err;
2157 
2158 	/*
2159 	 * We handle btree write errors by immediately halting the journal -
2160 	 * after we've done that, we can't issue any subsequent btree writes
2161 	 * because they might have pointers to new nodes that failed to write.
2162 	 *
2163 	 * Furthermore, there's no point in doing any more btree writes because
2164 	 * with the journal stopped, we're never going to update the journal to
2165 	 * reflect that those writes were done and the data flushed from the
2166 	 * journal:
2167 	 *
2168 	 * Also on journal error, the pending write may have updates that were
2169 	 * never journalled (interior nodes, see btree_update_nodes_written()) -
2170 	 * it's critical that we don't do the write in that case otherwise we
2171 	 * will have updates visible that weren't in the journal:
2172 	 *
2173 	 * Make sure to update b->written so bch2_btree_init_next() doesn't
2174 	 * break:
2175 	 */
2176 	if (bch2_journal_error(&c->journal) ||
2177 	    c->opts.nochanges)
2178 		goto err;
2179 
2180 	trace_and_count(c, btree_node_write, b, bytes_to_write, sectors_to_write);
2181 
2182 	wbio = container_of(bio_alloc_bioset(NULL,
2183 				buf_pages(data, sectors_to_write << 9),
2184 				REQ_OP_WRITE|REQ_META,
2185 				GFP_NOFS,
2186 				&c->btree_bio),
2187 			    struct btree_write_bio, wbio.bio);
2188 	wbio_init(&wbio->wbio.bio);
2189 	wbio->data			= data;
2190 	wbio->data_bytes		= bytes;
2191 	wbio->sector_offset		= b->written;
2192 	wbio->wbio.c			= c;
2193 	wbio->wbio.used_mempool		= used_mempool;
2194 	wbio->wbio.first_btree_write	= !b->written;
2195 	wbio->wbio.bio.bi_end_io	= btree_node_write_endio;
2196 	wbio->wbio.bio.bi_private	= b;
2197 
2198 	bch2_bio_map(&wbio->wbio.bio, data, sectors_to_write << 9);
2199 
2200 	bkey_copy(&wbio->key, &b->key);
2201 
2202 	b->written += sectors_to_write;
2203 
2204 	if (wbio->key.k.type == KEY_TYPE_btree_ptr_v2)
2205 		bkey_i_to_btree_ptr_v2(&wbio->key)->v.sectors_written =
2206 			cpu_to_le16(b->written);
2207 
2208 	atomic64_inc(&c->btree_write_stats[type].nr);
2209 	atomic64_add(bytes_to_write, &c->btree_write_stats[type].bytes);
2210 
2211 	INIT_WORK(&wbio->work, btree_write_submit);
2212 	queue_work(c->io_complete_wq, &wbio->work);
2213 	return;
2214 err:
2215 	set_btree_node_noevict(b);
2216 	b->written += sectors_to_write;
2217 nowrite:
2218 	btree_bounce_free(c, bytes, used_mempool, data);
2219 	__btree_node_write_done(c, b);
2220 }
2221 
2222 /*
2223  * Work that must be done with write lock held:
2224  */
2225 bool bch2_btree_post_write_cleanup(struct bch_fs *c, struct btree *b)
2226 {
2227 	bool invalidated_iter = false;
2228 	struct btree_node_entry *bne;
2229 	struct bset_tree *t;
2230 
2231 	if (!btree_node_just_written(b))
2232 		return false;
2233 
2234 	BUG_ON(b->whiteout_u64s);
2235 
2236 	clear_btree_node_just_written(b);
2237 
2238 	/*
2239 	 * Note: immediately after write, bset_written() doesn't work - the
2240 	 * amount of data we had to write after compaction might have been
2241 	 * smaller than the offset of the last bset.
2242 	 *
2243 	 * However, we know that all bsets have been written here, as long as
2244 	 * we're still holding the write lock:
2245 	 */
2246 
2247 	/*
2248 	 * XXX: decide if we really want to unconditionally sort down to a
2249 	 * single bset:
2250 	 */
2251 	if (b->nsets > 1) {
2252 		btree_node_sort(c, b, 0, b->nsets, true);
2253 		invalidated_iter = true;
2254 	} else {
2255 		invalidated_iter = bch2_drop_whiteouts(b, COMPACT_ALL);
2256 	}
2257 
2258 	for_each_bset(b, t)
2259 		set_needs_whiteout(bset(b, t), true);
2260 
2261 	bch2_btree_verify(c, b);
2262 
2263 	/*
2264 	 * If later we don't unconditionally sort down to a single bset, we have
2265 	 * to ensure this is still true:
2266 	 */
2267 	BUG_ON((void *) btree_bkey_last(b, bset_tree_last(b)) > write_block(b));
2268 
2269 	bne = want_new_bset(c, b);
2270 	if (bne)
2271 		bch2_bset_init_next(b, bne);
2272 
2273 	bch2_btree_build_aux_trees(b);
2274 
2275 	return invalidated_iter;
2276 }
2277 
2278 /*
2279  * Use this one if the node is intent locked:
2280  */
2281 void bch2_btree_node_write(struct bch_fs *c, struct btree *b,
2282 			   enum six_lock_type lock_type_held,
2283 			   unsigned flags)
2284 {
2285 	if (lock_type_held == SIX_LOCK_intent ||
2286 	    (lock_type_held == SIX_LOCK_read &&
2287 	     six_lock_tryupgrade(&b->c.lock))) {
2288 		__bch2_btree_node_write(c, b, flags);
2289 
2290 		/* don't cycle lock unnecessarily: */
2291 		if (btree_node_just_written(b) &&
2292 		    six_trylock_write(&b->c.lock)) {
2293 			bch2_btree_post_write_cleanup(c, b);
2294 			six_unlock_write(&b->c.lock);
2295 		}
2296 
2297 		if (lock_type_held == SIX_LOCK_read)
2298 			six_lock_downgrade(&b->c.lock);
2299 	} else {
2300 		__bch2_btree_node_write(c, b, flags);
2301 		if (lock_type_held == SIX_LOCK_write &&
2302 		    btree_node_just_written(b))
2303 			bch2_btree_post_write_cleanup(c, b);
2304 	}
2305 }
2306 
2307 static bool __bch2_btree_flush_all(struct bch_fs *c, unsigned flag)
2308 {
2309 	struct bucket_table *tbl;
2310 	struct rhash_head *pos;
2311 	struct btree *b;
2312 	unsigned i;
2313 	bool ret = false;
2314 restart:
2315 	rcu_read_lock();
2316 	for_each_cached_btree(b, c, tbl, i, pos)
2317 		if (test_bit(flag, &b->flags)) {
2318 			rcu_read_unlock();
2319 			wait_on_bit_io(&b->flags, flag, TASK_UNINTERRUPTIBLE);
2320 			ret = true;
2321 			goto restart;
2322 		}
2323 	rcu_read_unlock();
2324 
2325 	return ret;
2326 }
2327 
2328 bool bch2_btree_flush_all_reads(struct bch_fs *c)
2329 {
2330 	return __bch2_btree_flush_all(c, BTREE_NODE_read_in_flight);
2331 }
2332 
2333 bool bch2_btree_flush_all_writes(struct bch_fs *c)
2334 {
2335 	return __bch2_btree_flush_all(c, BTREE_NODE_write_in_flight);
2336 }
2337 
2338 static const char * const bch2_btree_write_types[] = {
2339 #define x(t, n) [n] = #t,
2340 	BCH_BTREE_WRITE_TYPES()
2341 	NULL
2342 };
2343 
2344 void bch2_btree_write_stats_to_text(struct printbuf *out, struct bch_fs *c)
2345 {
2346 	printbuf_tabstop_push(out, 20);
2347 	printbuf_tabstop_push(out, 10);
2348 
2349 	prt_tab(out);
2350 	prt_str(out, "nr");
2351 	prt_tab(out);
2352 	prt_str(out, "size");
2353 	prt_newline(out);
2354 
2355 	for (unsigned i = 0; i < BTREE_WRITE_TYPE_NR; i++) {
2356 		u64 nr		= atomic64_read(&c->btree_write_stats[i].nr);
2357 		u64 bytes	= atomic64_read(&c->btree_write_stats[i].bytes);
2358 
2359 		prt_printf(out, "%s:", bch2_btree_write_types[i]);
2360 		prt_tab(out);
2361 		prt_u64(out, nr);
2362 		prt_tab(out);
2363 		prt_human_readable_u64(out, nr ? div64_u64(bytes, nr) : 0);
2364 		prt_newline(out);
2365 	}
2366 }
2367