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Update bcachefs sources to 31c09369cd six locks: Fix an unitialized var
[bcachefs-tools-debian] / libbcachefs / btree_io.c
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.h"
18 #include "journal_reclaim.h"
19 #include "journal_seq_blacklist.h"
20 #include "super-io.h"
21 #include "trace.h"
22
23 #include <linux/sched/mm.h>
24
25 void bch2_btree_node_io_unlock(struct btree *b)
26 {
27         EBUG_ON(!btree_node_write_in_flight(b));
28
29         clear_btree_node_write_in_flight_inner(b);
30         clear_btree_node_write_in_flight(b);
31         wake_up_bit(&b->flags, BTREE_NODE_write_in_flight);
32 }
33
34 void bch2_btree_node_io_lock(struct btree *b)
35 {
36         bch2_assert_btree_nodes_not_locked();
37
38         wait_on_bit_lock_io(&b->flags, BTREE_NODE_write_in_flight,
39                             TASK_UNINTERRUPTIBLE);
40 }
41
42 void __bch2_btree_node_wait_on_read(struct btree *b)
43 {
44         wait_on_bit_io(&b->flags, BTREE_NODE_read_in_flight,
45                        TASK_UNINTERRUPTIBLE);
46 }
47
48 void __bch2_btree_node_wait_on_write(struct btree *b)
49 {
50         wait_on_bit_io(&b->flags, BTREE_NODE_write_in_flight,
51                        TASK_UNINTERRUPTIBLE);
52 }
53
54 void bch2_btree_node_wait_on_read(struct btree *b)
55 {
56         bch2_assert_btree_nodes_not_locked();
57
58         wait_on_bit_io(&b->flags, BTREE_NODE_read_in_flight,
59                        TASK_UNINTERRUPTIBLE);
60 }
61
62 void bch2_btree_node_wait_on_write(struct btree *b)
63 {
64         bch2_assert_btree_nodes_not_locked();
65
66         wait_on_bit_io(&b->flags, BTREE_NODE_write_in_flight,
67                        TASK_UNINTERRUPTIBLE);
68 }
69
70 static void verify_no_dups(struct btree *b,
71                            struct bkey_packed *start,
72                            struct bkey_packed *end)
73 {
74 #ifdef CONFIG_BCACHEFS_DEBUG
75         struct bkey_packed *k, *p;
76
77         if (start == end)
78                 return;
79
80         for (p = start, k = bkey_p_next(start);
81              k != end;
82              p = k, k = bkey_p_next(k)) {
83                 struct bkey l = bkey_unpack_key(b, p);
84                 struct bkey r = bkey_unpack_key(b, k);
85
86                 BUG_ON(bpos_ge(l.p, bkey_start_pos(&r)));
87         }
88 #endif
89 }
90
91 static void set_needs_whiteout(struct bset *i, int v)
92 {
93         struct bkey_packed *k;
94
95         for (k = i->start; k != vstruct_last(i); k = bkey_p_next(k))
96                 k->needs_whiteout = v;
97 }
98
99 static void btree_bounce_free(struct bch_fs *c, size_t size,
100                               bool used_mempool, void *p)
101 {
102         if (used_mempool)
103                 mempool_free(p, &c->btree_bounce_pool);
104         else
105                 vpfree(p, size);
106 }
107
108 static void *btree_bounce_alloc(struct bch_fs *c, size_t size,
109                                 bool *used_mempool)
110 {
111         unsigned flags = memalloc_nofs_save();
112         void *p;
113
114         BUG_ON(size > btree_bytes(c));
115
116         *used_mempool = false;
117         p = vpmalloc(size, __GFP_NOWARN|GFP_NOWAIT);
118         if (!p) {
119                 *used_mempool = true;
120                 p = mempool_alloc(&c->btree_bounce_pool, GFP_NOIO);
121         }
122         memalloc_nofs_restore(flags);
123         return p;
124 }
125
126 static void sort_bkey_ptrs(const struct btree *bt,
127                            struct bkey_packed **ptrs, unsigned nr)
128 {
129         unsigned n = nr, a = nr / 2, b, c, d;
130
131         if (!a)
132                 return;
133
134         /* Heap sort: see lib/sort.c: */
135         while (1) {
136                 if (a)
137                         a--;
138                 else if (--n)
139                         swap(ptrs[0], ptrs[n]);
140                 else
141                         break;
142
143                 for (b = a; c = 2 * b + 1, (d = c + 1) < n;)
144                         b = bch2_bkey_cmp_packed(bt,
145                                             ptrs[c],
146                                             ptrs[d]) >= 0 ? c : d;
147                 if (d == n)
148                         b = c;
149
150                 while (b != a &&
151                        bch2_bkey_cmp_packed(bt,
152                                        ptrs[a],
153                                        ptrs[b]) >= 0)
154                         b = (b - 1) / 2;
155                 c = b;
156                 while (b != a) {
157                         b = (b - 1) / 2;
158                         swap(ptrs[b], ptrs[c]);
159                 }
160         }
161 }
162
163 static void bch2_sort_whiteouts(struct bch_fs *c, struct btree *b)
164 {
165         struct bkey_packed *new_whiteouts, **ptrs, **ptrs_end, *k;
166         bool used_mempool = false;
167         size_t bytes = b->whiteout_u64s * sizeof(u64);
168
169         if (!b->whiteout_u64s)
170                 return;
171
172         new_whiteouts = btree_bounce_alloc(c, bytes, &used_mempool);
173
174         ptrs = ptrs_end = ((void *) new_whiteouts + bytes);
175
176         for (k = unwritten_whiteouts_start(c, b);
177              k != unwritten_whiteouts_end(c, b);
178              k = bkey_p_next(k))
179                 *--ptrs = k;
180
181         sort_bkey_ptrs(b, ptrs, ptrs_end - ptrs);
182
183         k = new_whiteouts;
184
185         while (ptrs != ptrs_end) {
186                 bkey_copy(k, *ptrs);
187                 k = bkey_p_next(k);
188                 ptrs++;
189         }
190
191         verify_no_dups(b, new_whiteouts,
192                        (void *) ((u64 *) new_whiteouts + b->whiteout_u64s));
193
194         memcpy_u64s(unwritten_whiteouts_start(c, b),
195                     new_whiteouts, b->whiteout_u64s);
196
197         btree_bounce_free(c, bytes, used_mempool, new_whiteouts);
198 }
199
200 static bool should_compact_bset(struct btree *b, struct bset_tree *t,
201                                 bool compacting, enum compact_mode mode)
202 {
203         if (!bset_dead_u64s(b, t))
204                 return false;
205
206         switch (mode) {
207         case COMPACT_LAZY:
208                 return should_compact_bset_lazy(b, t) ||
209                         (compacting && !bset_written(b, bset(b, t)));
210         case COMPACT_ALL:
211                 return true;
212         default:
213                 BUG();
214         }
215 }
216
217 static bool bch2_drop_whiteouts(struct btree *b, enum compact_mode mode)
218 {
219         struct bset_tree *t;
220         bool ret = false;
221
222         for_each_bset(b, t) {
223                 struct bset *i = bset(b, t);
224                 struct bkey_packed *k, *n, *out, *start, *end;
225                 struct btree_node_entry *src = NULL, *dst = NULL;
226
227                 if (t != b->set && !bset_written(b, i)) {
228                         src = container_of(i, struct btree_node_entry, keys);
229                         dst = max(write_block(b),
230                                   (void *) btree_bkey_last(b, t - 1));
231                 }
232
233                 if (src != dst)
234                         ret = true;
235
236                 if (!should_compact_bset(b, t, ret, mode)) {
237                         if (src != dst) {
238                                 memmove(dst, src, sizeof(*src) +
239                                         le16_to_cpu(src->keys.u64s) *
240                                         sizeof(u64));
241                                 i = &dst->keys;
242                                 set_btree_bset(b, t, i);
243                         }
244                         continue;
245                 }
246
247                 start   = btree_bkey_first(b, t);
248                 end     = btree_bkey_last(b, t);
249
250                 if (src != dst) {
251                         memmove(dst, src, sizeof(*src));
252                         i = &dst->keys;
253                         set_btree_bset(b, t, i);
254                 }
255
256                 out = i->start;
257
258                 for (k = start; k != end; k = n) {
259                         n = bkey_p_next(k);
260
261                         if (!bkey_deleted(k)) {
262                                 bkey_copy(out, k);
263                                 out = bkey_p_next(out);
264                         } else {
265                                 BUG_ON(k->needs_whiteout);
266                         }
267                 }
268
269                 i->u64s = cpu_to_le16((u64 *) out - i->_data);
270                 set_btree_bset_end(b, t);
271                 bch2_bset_set_no_aux_tree(b, t);
272                 ret = true;
273         }
274
275         bch2_verify_btree_nr_keys(b);
276
277         bch2_btree_build_aux_trees(b);
278
279         return ret;
280 }
281
282 bool bch2_compact_whiteouts(struct bch_fs *c, struct btree *b,
283                             enum compact_mode mode)
284 {
285         return bch2_drop_whiteouts(b, mode);
286 }
287
288 static void btree_node_sort(struct bch_fs *c, struct btree *b,
289                             unsigned start_idx,
290                             unsigned end_idx,
291                             bool filter_whiteouts)
292 {
293         struct btree_node *out;
294         struct sort_iter sort_iter;
295         struct bset_tree *t;
296         struct bset *start_bset = bset(b, &b->set[start_idx]);
297         bool used_mempool = false;
298         u64 start_time, seq = 0;
299         unsigned i, u64s = 0, bytes, shift = end_idx - start_idx - 1;
300         bool sorting_entire_node = start_idx == 0 &&
301                 end_idx == b->nsets;
302
303         sort_iter_init(&sort_iter, b);
304
305         for (t = b->set + start_idx;
306              t < b->set + end_idx;
307              t++) {
308                 u64s += le16_to_cpu(bset(b, t)->u64s);
309                 sort_iter_add(&sort_iter,
310                               btree_bkey_first(b, t),
311                               btree_bkey_last(b, t));
312         }
313
314         bytes = sorting_entire_node
315                 ? btree_bytes(c)
316                 : __vstruct_bytes(struct btree_node, u64s);
317
318         out = btree_bounce_alloc(c, bytes, &used_mempool);
319
320         start_time = local_clock();
321
322         u64s = bch2_sort_keys(out->keys.start, &sort_iter, filter_whiteouts);
323
324         out->keys.u64s = cpu_to_le16(u64s);
325
326         BUG_ON(vstruct_end(&out->keys) > (void *) out + bytes);
327
328         if (sorting_entire_node)
329                 bch2_time_stats_update(&c->times[BCH_TIME_btree_node_sort],
330                                        start_time);
331
332         /* Make sure we preserve bset journal_seq: */
333         for (t = b->set + start_idx; t < b->set + end_idx; t++)
334                 seq = max(seq, le64_to_cpu(bset(b, t)->journal_seq));
335         start_bset->journal_seq = cpu_to_le64(seq);
336
337         if (sorting_entire_node) {
338                 unsigned u64s = le16_to_cpu(out->keys.u64s);
339
340                 BUG_ON(bytes != btree_bytes(c));
341
342                 /*
343                  * Our temporary buffer is the same size as the btree node's
344                  * buffer, we can just swap buffers instead of doing a big
345                  * memcpy()
346                  */
347                 *out = *b->data;
348                 out->keys.u64s = cpu_to_le16(u64s);
349                 swap(out, b->data);
350                 set_btree_bset(b, b->set, &b->data->keys);
351         } else {
352                 start_bset->u64s = out->keys.u64s;
353                 memcpy_u64s(start_bset->start,
354                             out->keys.start,
355                             le16_to_cpu(out->keys.u64s));
356         }
357
358         for (i = start_idx + 1; i < end_idx; i++)
359                 b->nr.bset_u64s[start_idx] +=
360                         b->nr.bset_u64s[i];
361
362         b->nsets -= shift;
363
364         for (i = start_idx + 1; i < b->nsets; i++) {
365                 b->nr.bset_u64s[i]      = b->nr.bset_u64s[i + shift];
366                 b->set[i]               = b->set[i + shift];
367         }
368
369         for (i = b->nsets; i < MAX_BSETS; i++)
370                 b->nr.bset_u64s[i] = 0;
371
372         set_btree_bset_end(b, &b->set[start_idx]);
373         bch2_bset_set_no_aux_tree(b, &b->set[start_idx]);
374
375         btree_bounce_free(c, bytes, used_mempool, out);
376
377         bch2_verify_btree_nr_keys(b);
378 }
379
380 void bch2_btree_sort_into(struct bch_fs *c,
381                          struct btree *dst,
382                          struct btree *src)
383 {
384         struct btree_nr_keys nr;
385         struct btree_node_iter src_iter;
386         u64 start_time = local_clock();
387
388         BUG_ON(dst->nsets != 1);
389
390         bch2_bset_set_no_aux_tree(dst, dst->set);
391
392         bch2_btree_node_iter_init_from_start(&src_iter, src);
393
394         nr = bch2_sort_repack(btree_bset_first(dst),
395                         src, &src_iter,
396                         &dst->format,
397                         true);
398
399         bch2_time_stats_update(&c->times[BCH_TIME_btree_node_sort],
400                                start_time);
401
402         set_btree_bset_end(dst, dst->set);
403
404         dst->nr.live_u64s       += nr.live_u64s;
405         dst->nr.bset_u64s[0]    += nr.bset_u64s[0];
406         dst->nr.packed_keys     += nr.packed_keys;
407         dst->nr.unpacked_keys   += nr.unpacked_keys;
408
409         bch2_verify_btree_nr_keys(dst);
410 }
411
412 #define SORT_CRIT       (4096 / sizeof(u64))
413
414 /*
415  * We're about to add another bset to the btree node, so if there's currently
416  * too many bsets - sort some of them together:
417  */
418 static bool btree_node_compact(struct bch_fs *c, struct btree *b)
419 {
420         unsigned unwritten_idx;
421         bool ret = false;
422
423         for (unwritten_idx = 0;
424              unwritten_idx < b->nsets;
425              unwritten_idx++)
426                 if (!bset_written(b, bset(b, &b->set[unwritten_idx])))
427                         break;
428
429         if (b->nsets - unwritten_idx > 1) {
430                 btree_node_sort(c, b, unwritten_idx,
431                                 b->nsets, false);
432                 ret = true;
433         }
434
435         if (unwritten_idx > 1) {
436                 btree_node_sort(c, b, 0, unwritten_idx, false);
437                 ret = true;
438         }
439
440         return ret;
441 }
442
443 void bch2_btree_build_aux_trees(struct btree *b)
444 {
445         struct bset_tree *t;
446
447         for_each_bset(b, t)
448                 bch2_bset_build_aux_tree(b, t,
449                                 !bset_written(b, bset(b, t)) &&
450                                 t == bset_tree_last(b));
451 }
452
453 /*
454  * If we have MAX_BSETS (3) bsets, should we sort them all down to just one?
455  *
456  * The first bset is going to be of similar order to the size of the node, the
457  * last bset is bounded by btree_write_set_buffer(), which is set to keep the
458  * memmove on insert from being too expensive: the middle bset should, ideally,
459  * be the geometric mean of the first and the last.
460  *
461  * Returns true if the middle bset is greater than that geometric mean:
462  */
463 static inline bool should_compact_all(struct bch_fs *c, struct btree *b)
464 {
465         unsigned mid_u64s_bits =
466                 (ilog2(btree_max_u64s(c)) + BTREE_WRITE_SET_U64s_BITS) / 2;
467
468         return bset_u64s(&b->set[1]) > 1U << mid_u64s_bits;
469 }
470
471 /*
472  * @bch_btree_init_next - initialize a new (unwritten) bset that can then be
473  * inserted into
474  *
475  * Safe to call if there already is an unwritten bset - will only add a new bset
476  * if @b doesn't already have one.
477  *
478  * Returns true if we sorted (i.e. invalidated iterators
479  */
480 void bch2_btree_init_next(struct btree_trans *trans, struct btree *b)
481 {
482         struct bch_fs *c = trans->c;
483         struct btree_node_entry *bne;
484         bool reinit_iter = false;
485
486         EBUG_ON(!six_lock_counts(&b->c.lock).n[SIX_LOCK_write]);
487         BUG_ON(bset_written(b, bset(b, &b->set[1])));
488         BUG_ON(btree_node_just_written(b));
489
490         if (b->nsets == MAX_BSETS &&
491             !btree_node_write_in_flight(b) &&
492             should_compact_all(c, b)) {
493                 bch2_btree_node_write(c, b, SIX_LOCK_write,
494                                       BTREE_WRITE_init_next_bset);
495                 reinit_iter = true;
496         }
497
498         if (b->nsets == MAX_BSETS &&
499             btree_node_compact(c, b))
500                 reinit_iter = true;
501
502         BUG_ON(b->nsets >= MAX_BSETS);
503
504         bne = want_new_bset(c, b);
505         if (bne)
506                 bch2_bset_init_next(c, b, bne);
507
508         bch2_btree_build_aux_trees(b);
509
510         if (reinit_iter)
511                 bch2_trans_node_reinit_iter(trans, b);
512 }
513
514 static void btree_pos_to_text(struct printbuf *out, struct bch_fs *c,
515                           struct btree *b)
516 {
517         prt_printf(out, "%s level %u/%u\n  ",
518                bch2_btree_ids[b->c.btree_id],
519                b->c.level,
520                c->btree_roots[b->c.btree_id].level);
521         bch2_bkey_val_to_text(out, c, bkey_i_to_s_c(&b->key));
522 }
523
524 static void btree_err_msg(struct printbuf *out, struct bch_fs *c,
525                           struct bch_dev *ca,
526                           struct btree *b, struct bset *i,
527                           unsigned offset, int write)
528 {
529         prt_printf(out, bch2_log_msg(c, "%s"),
530                    write == READ
531                    ? "error validating btree node "
532                    : "corrupt btree node before write ");
533         if (ca)
534                 prt_printf(out, "on %s ", ca->name);
535         prt_printf(out, "at btree ");
536         btree_pos_to_text(out, c, b);
537
538         prt_printf(out, "\n  node offset %u", b->written);
539         if (i)
540                 prt_printf(out, " bset u64s %u", le16_to_cpu(i->u64s));
541         prt_str(out, ": ");
542 }
543
544 enum btree_err_type {
545         /*
546          * We can repair this locally, and we're after the checksum check so
547          * there's no need to try another replica:
548          */
549         BTREE_ERR_FIXABLE,
550         /*
551          * We can repair this if we have to, but we should try reading another
552          * replica if we can:
553          */
554         BTREE_ERR_WANT_RETRY,
555         /*
556          * Read another replica if we have one, otherwise consider the whole
557          * node bad:
558          */
559         BTREE_ERR_MUST_RETRY,
560         BTREE_ERR_BAD_NODE,
561         BTREE_ERR_INCOMPATIBLE,
562 };
563
564 enum btree_validate_ret {
565         BTREE_RETRY_READ = 64,
566 };
567
568 static int __btree_err(enum btree_err_type type,
569                        struct bch_fs *c,
570                        struct bch_dev *ca,
571                        struct btree *b,
572                        struct bset *i,
573                        int write,
574                        bool have_retry,
575                        const char *fmt, ...)
576 {
577         struct printbuf out = PRINTBUF;
578         va_list args;
579         int ret = -BCH_ERR_fsck_fix;
580
581         btree_err_msg(&out, c, ca, b, i, b->written, write);
582
583         va_start(args, fmt);
584         prt_vprintf(&out, fmt, args);
585         va_end(args);
586
587         if (write == WRITE) {
588                 bch2_print_string_as_lines(KERN_ERR, out.buf);
589                 ret = c->opts.errors == BCH_ON_ERROR_continue
590                         ? 0
591                         : -BCH_ERR_fsck_errors_not_fixed;
592                 goto out;
593         }
594
595         if (!have_retry && type == BTREE_ERR_WANT_RETRY)
596                 type = BTREE_ERR_FIXABLE;
597         if (!have_retry && type == BTREE_ERR_MUST_RETRY)
598                 type = BTREE_ERR_BAD_NODE;
599
600         switch (type) {
601         case BTREE_ERR_FIXABLE:
602                 mustfix_fsck_err(c, "%s", out.buf);
603                 ret = -BCH_ERR_fsck_fix;
604                 break;
605         case BTREE_ERR_WANT_RETRY:
606         case BTREE_ERR_MUST_RETRY:
607                 bch2_print_string_as_lines(KERN_ERR, out.buf);
608                 ret = BTREE_RETRY_READ;
609                 break;
610         case BTREE_ERR_BAD_NODE:
611                 bch2_print_string_as_lines(KERN_ERR, out.buf);
612                 bch2_topology_error(c);
613                 ret = -BCH_ERR_need_topology_repair;
614                 break;
615         case BTREE_ERR_INCOMPATIBLE:
616                 bch2_print_string_as_lines(KERN_ERR, out.buf);
617                 ret = -BCH_ERR_fsck_errors_not_fixed;
618                 break;
619         default:
620                 BUG();
621         }
622 out:
623 fsck_err:
624         printbuf_exit(&out);
625         return ret;
626 }
627
628 #define btree_err(type, c, ca, b, i, msg, ...)                          \
629 ({                                                                      \
630         int _ret = __btree_err(type, c, ca, b, i, write, have_retry, msg, ##__VA_ARGS__);\
631                                                                         \
632         if (_ret != -BCH_ERR_fsck_fix)                                  \
633                 goto fsck_err;                                          \
634         *saw_error = true;                                              \
635 })
636
637 #define btree_err_on(cond, ...) ((cond) ? btree_err(__VA_ARGS__) : false)
638
639 /*
640  * When btree topology repair changes the start or end of a node, that might
641  * mean we have to drop keys that are no longer inside the node:
642  */
643 __cold
644 void bch2_btree_node_drop_keys_outside_node(struct btree *b)
645 {
646         struct bset_tree *t;
647         struct bkey_s_c k;
648         struct bkey unpacked;
649         struct btree_node_iter iter;
650
651         for_each_bset(b, t) {
652                 struct bset *i = bset(b, t);
653                 struct bkey_packed *k;
654
655                 for (k = i->start; k != vstruct_last(i); k = bkey_p_next(k))
656                         if (bkey_cmp_left_packed(b, k, &b->data->min_key) >= 0)
657                                 break;
658
659                 if (k != i->start) {
660                         unsigned shift = (u64 *) k - (u64 *) i->start;
661
662                         memmove_u64s_down(i->start, k,
663                                           (u64 *) vstruct_end(i) - (u64 *) k);
664                         i->u64s = cpu_to_le16(le16_to_cpu(i->u64s) - shift);
665                         set_btree_bset_end(b, t);
666                 }
667
668                 for (k = i->start; k != vstruct_last(i); k = bkey_p_next(k))
669                         if (bkey_cmp_left_packed(b, k, &b->data->max_key) > 0)
670                                 break;
671
672                 if (k != vstruct_last(i)) {
673                         i->u64s = cpu_to_le16((u64 *) k - (u64 *) i->start);
674                         set_btree_bset_end(b, t);
675                 }
676         }
677
678         /*
679          * Always rebuild search trees: eytzinger search tree nodes directly
680          * depend on the values of min/max key:
681          */
682         bch2_bset_set_no_aux_tree(b, b->set);
683         bch2_btree_build_aux_trees(b);
684
685         for_each_btree_node_key_unpack(b, k, &iter, &unpacked) {
686                 BUG_ON(bpos_lt(k.k->p, b->data->min_key));
687                 BUG_ON(bpos_gt(k.k->p, b->data->max_key));
688         }
689 }
690
691 static int validate_bset(struct bch_fs *c, struct bch_dev *ca,
692                          struct btree *b, struct bset *i,
693                          unsigned offset, unsigned sectors,
694                          int write, bool have_retry, bool *saw_error)
695 {
696         unsigned version = le16_to_cpu(i->version);
697         const char *err;
698         struct printbuf buf1 = PRINTBUF;
699         struct printbuf buf2 = PRINTBUF;
700         int ret = 0;
701
702         btree_err_on((version != BCH_BSET_VERSION_OLD &&
703                       version < bcachefs_metadata_version_min) ||
704                      version >= bcachefs_metadata_version_max,
705                      BTREE_ERR_INCOMPATIBLE, c, ca, b, i,
706                      "unsupported bset version");
707
708         if (btree_err_on(version < c->sb.version_min,
709                          BTREE_ERR_FIXABLE, c, NULL, b, i,
710                          "bset version %u older than superblock version_min %u",
711                          version, c->sb.version_min)) {
712                 mutex_lock(&c->sb_lock);
713                 c->disk_sb.sb->version_min = cpu_to_le16(version);
714                 bch2_write_super(c);
715                 mutex_unlock(&c->sb_lock);
716         }
717
718         if (btree_err_on(version > c->sb.version,
719                          BTREE_ERR_FIXABLE, c, NULL, b, i,
720                          "bset version %u newer than superblock version %u",
721                          version, c->sb.version)) {
722                 mutex_lock(&c->sb_lock);
723                 c->disk_sb.sb->version = cpu_to_le16(version);
724                 bch2_write_super(c);
725                 mutex_unlock(&c->sb_lock);
726         }
727
728         btree_err_on(BSET_SEPARATE_WHITEOUTS(i),
729                      BTREE_ERR_INCOMPATIBLE, c, ca, b, i,
730                      "BSET_SEPARATE_WHITEOUTS no longer supported");
731
732         if (btree_err_on(offset + sectors > btree_sectors(c),
733                          BTREE_ERR_FIXABLE, c, ca, b, i,
734                          "bset past end of btree node")) {
735                 i->u64s = 0;
736                 ret = 0;
737                 goto out;
738         }
739
740         btree_err_on(offset && !i->u64s,
741                      BTREE_ERR_FIXABLE, c, ca, b, i,
742                      "empty bset");
743
744         btree_err_on(BSET_OFFSET(i) &&
745                      BSET_OFFSET(i) != offset,
746                      BTREE_ERR_WANT_RETRY, c, ca, b, i,
747                      "bset at wrong sector offset");
748
749         if (!offset) {
750                 struct btree_node *bn =
751                         container_of(i, struct btree_node, keys);
752                 /* These indicate that we read the wrong btree node: */
753
754                 if (b->key.k.type == KEY_TYPE_btree_ptr_v2) {
755                         struct bch_btree_ptr_v2 *bp =
756                                 &bkey_i_to_btree_ptr_v2(&b->key)->v;
757
758                         /* XXX endianness */
759                         btree_err_on(bp->seq != bn->keys.seq,
760                                      BTREE_ERR_MUST_RETRY, c, ca, b, NULL,
761                                      "incorrect sequence number (wrong btree node)");
762                 }
763
764                 btree_err_on(BTREE_NODE_ID(bn) != b->c.btree_id,
765                              BTREE_ERR_MUST_RETRY, c, ca, b, i,
766                              "incorrect btree id");
767
768                 btree_err_on(BTREE_NODE_LEVEL(bn) != b->c.level,
769                              BTREE_ERR_MUST_RETRY, c, ca, b, i,
770                              "incorrect level");
771
772                 if (!write)
773                         compat_btree_node(b->c.level, b->c.btree_id, version,
774                                           BSET_BIG_ENDIAN(i), write, bn);
775
776                 if (b->key.k.type == KEY_TYPE_btree_ptr_v2) {
777                         struct bch_btree_ptr_v2 *bp =
778                                 &bkey_i_to_btree_ptr_v2(&b->key)->v;
779
780                         if (BTREE_PTR_RANGE_UPDATED(bp)) {
781                                 b->data->min_key = bp->min_key;
782                                 b->data->max_key = b->key.k.p;
783                         }
784
785                         btree_err_on(!bpos_eq(b->data->min_key, bp->min_key),
786                                      BTREE_ERR_MUST_RETRY, c, ca, b, NULL,
787                                      "incorrect min_key: got %s should be %s",
788                                      (printbuf_reset(&buf1),
789                                       bch2_bpos_to_text(&buf1, bn->min_key), buf1.buf),
790                                      (printbuf_reset(&buf2),
791                                       bch2_bpos_to_text(&buf2, bp->min_key), buf2.buf));
792                 }
793
794                 btree_err_on(!bpos_eq(bn->max_key, b->key.k.p),
795                              BTREE_ERR_MUST_RETRY, c, ca, b, i,
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                 err = bch2_bkey_format_validate(&bn->format);
805                 btree_err_on(err,
806                              BTREE_ERR_BAD_NODE, c, ca, b, i,
807                              "invalid bkey format: %s", err);
808
809                 compat_bformat(b->c.level, b->c.btree_id, version,
810                                BSET_BIG_ENDIAN(i), write,
811                                &bn->format);
812         }
813 out:
814 fsck_err:
815         printbuf_exit(&buf2);
816         printbuf_exit(&buf1);
817         return ret;
818 }
819
820 static int bset_key_invalid(struct bch_fs *c, struct btree *b,
821                             struct bkey_s_c k,
822                             bool updated_range, int rw,
823                             struct printbuf *err)
824 {
825         return __bch2_bkey_invalid(c, k, btree_node_type(b), READ, err) ?:
826                 (!updated_range ? bch2_bkey_in_btree_node(b, k, err) : 0) ?:
827                 (rw == WRITE ? bch2_bkey_val_invalid(c, k, READ, err) : 0);
828 }
829
830 static int validate_bset_keys(struct bch_fs *c, struct btree *b,
831                          struct bset *i, int write,
832                          bool have_retry, bool *saw_error)
833 {
834         unsigned version = le16_to_cpu(i->version);
835         struct bkey_packed *k, *prev = NULL;
836         struct printbuf buf = PRINTBUF;
837         bool updated_range = b->key.k.type == KEY_TYPE_btree_ptr_v2 &&
838                 BTREE_PTR_RANGE_UPDATED(&bkey_i_to_btree_ptr_v2(&b->key)->v);
839         int ret = 0;
840
841         for (k = i->start;
842              k != vstruct_last(i);) {
843                 struct bkey_s u;
844                 struct bkey tmp;
845
846                 if (btree_err_on(bkey_p_next(k) > vstruct_last(i),
847                                  BTREE_ERR_FIXABLE, c, NULL, b, i,
848                                  "key extends past end of bset")) {
849                         i->u64s = cpu_to_le16((u64 *) k - i->_data);
850                         break;
851                 }
852
853                 if (btree_err_on(k->format > KEY_FORMAT_CURRENT,
854                                  BTREE_ERR_FIXABLE, c, NULL, b, i,
855                                  "invalid bkey format %u", k->format)) {
856                         i->u64s = cpu_to_le16(le16_to_cpu(i->u64s) - k->u64s);
857                         memmove_u64s_down(k, bkey_p_next(k),
858                                           (u64 *) vstruct_end(i) - (u64 *) k);
859                         continue;
860                 }
861
862                 /* XXX: validate k->u64s */
863                 if (!write)
864                         bch2_bkey_compat(b->c.level, b->c.btree_id, version,
865                                     BSET_BIG_ENDIAN(i), write,
866                                     &b->format, k);
867
868                 u = __bkey_disassemble(b, k, &tmp);
869
870                 printbuf_reset(&buf);
871                 if (bset_key_invalid(c, b, u.s_c, updated_range, write, &buf)) {
872                         printbuf_reset(&buf);
873                         prt_printf(&buf, "invalid bkey:  ");
874                         bset_key_invalid(c, b, u.s_c, updated_range, write, &buf);
875                         prt_printf(&buf, "\n  ");
876                         bch2_bkey_val_to_text(&buf, c, u.s_c);
877
878                         btree_err(BTREE_ERR_FIXABLE, c, NULL, b, i, "%s", buf.buf);
879
880                         i->u64s = cpu_to_le16(le16_to_cpu(i->u64s) - k->u64s);
881                         memmove_u64s_down(k, bkey_p_next(k),
882                                           (u64 *) vstruct_end(i) - (u64 *) k);
883                         continue;
884                 }
885
886                 if (write)
887                         bch2_bkey_compat(b->c.level, b->c.btree_id, version,
888                                     BSET_BIG_ENDIAN(i), write,
889                                     &b->format, k);
890
891                 if (prev && bkey_iter_cmp(b, prev, k) > 0) {
892                         struct bkey up = bkey_unpack_key(b, prev);
893
894                         printbuf_reset(&buf);
895                         prt_printf(&buf, "keys out of order: ");
896                         bch2_bkey_to_text(&buf, &up);
897                         prt_printf(&buf, " > ");
898                         bch2_bkey_to_text(&buf, u.k);
899
900                         bch2_dump_bset(c, b, i, 0);
901
902                         if (btree_err(BTREE_ERR_FIXABLE, c, NULL, b, i, "%s", buf.buf)) {
903                                 i->u64s = cpu_to_le16(le16_to_cpu(i->u64s) - k->u64s);
904                                 memmove_u64s_down(k, bkey_p_next(k),
905                                                   (u64 *) vstruct_end(i) - (u64 *) k);
906                                 continue;
907                         }
908                 }
909
910                 prev = k;
911                 k = bkey_p_next(k);
912         }
913 fsck_err:
914         printbuf_exit(&buf);
915         return ret;
916 }
917
918 int bch2_btree_node_read_done(struct bch_fs *c, struct bch_dev *ca,
919                               struct btree *b, bool have_retry, bool *saw_error)
920 {
921         struct btree_node_entry *bne;
922         struct sort_iter *iter;
923         struct btree_node *sorted;
924         struct bkey_packed *k;
925         struct bch_extent_ptr *ptr;
926         struct bset *i;
927         bool used_mempool, blacklisted;
928         bool updated_range = b->key.k.type == KEY_TYPE_btree_ptr_v2 &&
929                 BTREE_PTR_RANGE_UPDATED(&bkey_i_to_btree_ptr_v2(&b->key)->v);
930         unsigned u64s;
931         unsigned blacklisted_written, nonblacklisted_written = 0;
932         unsigned ptr_written = btree_ptr_sectors_written(&b->key);
933         struct printbuf buf = PRINTBUF;
934         int ret = 0, retry_read = 0, write = READ;
935
936         b->version_ondisk = U16_MAX;
937         /* We might get called multiple times on read retry: */
938         b->written = 0;
939
940         iter = mempool_alloc(&c->fill_iter, GFP_NOIO);
941         sort_iter_init(iter, b);
942         iter->size = (btree_blocks(c) + 1) * 2;
943
944         if (bch2_meta_read_fault("btree"))
945                 btree_err(BTREE_ERR_MUST_RETRY, c, ca, b, NULL,
946                           "dynamic fault");
947
948         btree_err_on(le64_to_cpu(b->data->magic) != bset_magic(c),
949                      BTREE_ERR_MUST_RETRY, c, ca, b, NULL,
950                      "bad magic: want %llx, got %llx",
951                      bset_magic(c), le64_to_cpu(b->data->magic));
952
953         btree_err_on(!b->data->keys.seq,
954                      BTREE_ERR_MUST_RETRY, c, ca, b, NULL,
955                      "bad btree header: seq 0");
956
957         if (b->key.k.type == KEY_TYPE_btree_ptr_v2) {
958                 struct bch_btree_ptr_v2 *bp =
959                         &bkey_i_to_btree_ptr_v2(&b->key)->v;
960
961                 btree_err_on(b->data->keys.seq != bp->seq,
962                              BTREE_ERR_MUST_RETRY, c, ca, b, NULL,
963                              "got wrong btree node (seq %llx want %llx)",
964                              b->data->keys.seq, bp->seq);
965         }
966
967         while (b->written < (ptr_written ?: btree_sectors(c))) {
968                 unsigned sectors;
969                 struct nonce nonce;
970                 struct bch_csum csum;
971                 bool first = !b->written;
972
973                 if (!b->written) {
974                         i = &b->data->keys;
975
976                         btree_err_on(!bch2_checksum_type_valid(c, BSET_CSUM_TYPE(i)),
977                                      BTREE_ERR_WANT_RETRY, c, ca, b, i,
978                                      "unknown checksum type %llu",
979                                      BSET_CSUM_TYPE(i));
980
981                         nonce = btree_nonce(i, b->written << 9);
982                         csum = csum_vstruct(c, BSET_CSUM_TYPE(i), nonce, b->data);
983
984                         btree_err_on(bch2_crc_cmp(csum, b->data->csum),
985                                      BTREE_ERR_WANT_RETRY, c, ca, b, i,
986                                      "invalid checksum");
987
988                         ret = bset_encrypt(c, i, b->written << 9);
989                         if (bch2_fs_fatal_err_on(ret, c,
990                                         "error decrypting btree node: %i", ret))
991                                 goto fsck_err;
992
993                         btree_err_on(btree_node_type_is_extents(btree_node_type(b)) &&
994                                      !BTREE_NODE_NEW_EXTENT_OVERWRITE(b->data),
995                                      BTREE_ERR_INCOMPATIBLE, c, NULL, b, NULL,
996                                      "btree node does not have NEW_EXTENT_OVERWRITE set");
997
998                         sectors = vstruct_sectors(b->data, c->block_bits);
999                 } else {
1000                         bne = write_block(b);
1001                         i = &bne->keys;
1002
1003                         if (i->seq != b->data->keys.seq)
1004                                 break;
1005
1006                         btree_err_on(!bch2_checksum_type_valid(c, BSET_CSUM_TYPE(i)),
1007                                      BTREE_ERR_WANT_RETRY, c, ca, b, i,
1008                                      "unknown checksum type %llu",
1009                                      BSET_CSUM_TYPE(i));
1010
1011                         nonce = btree_nonce(i, b->written << 9);
1012                         csum = csum_vstruct(c, BSET_CSUM_TYPE(i), nonce, bne);
1013
1014                         btree_err_on(bch2_crc_cmp(csum, bne->csum),
1015                                      BTREE_ERR_WANT_RETRY, c, ca, b, i,
1016                                      "invalid checksum");
1017
1018                         ret = bset_encrypt(c, i, b->written << 9);
1019                         if (bch2_fs_fatal_err_on(ret, c,
1020                                         "error decrypting btree node: %i\n", ret))
1021                                 goto fsck_err;
1022
1023                         sectors = vstruct_sectors(bne, c->block_bits);
1024                 }
1025
1026                 b->version_ondisk = min(b->version_ondisk,
1027                                         le16_to_cpu(i->version));
1028
1029                 ret = validate_bset(c, ca, b, i, b->written, sectors,
1030                                     READ, have_retry, saw_error);
1031                 if (ret)
1032                         goto fsck_err;
1033
1034                 if (!b->written)
1035                         btree_node_set_format(b, b->data->format);
1036
1037                 ret = validate_bset_keys(c, b, i, READ, have_retry, saw_error);
1038                 if (ret)
1039                         goto fsck_err;
1040
1041                 SET_BSET_BIG_ENDIAN(i, CPU_BIG_ENDIAN);
1042
1043                 blacklisted = bch2_journal_seq_is_blacklisted(c,
1044                                         le64_to_cpu(i->journal_seq),
1045                                         true);
1046
1047                 btree_err_on(blacklisted && first,
1048                              BTREE_ERR_FIXABLE, c, ca, b, i,
1049                              "first btree node bset has blacklisted journal seq (%llu)",
1050                              le64_to_cpu(i->journal_seq));
1051
1052                 btree_err_on(blacklisted && ptr_written,
1053                              BTREE_ERR_FIXABLE, c, ca, b, i,
1054                              "found blacklisted bset (journal seq %llu) in btree node at offset %u-%u/%u",
1055                              le64_to_cpu(i->journal_seq),
1056                              b->written, b->written + sectors, ptr_written);
1057
1058                 b->written += sectors;
1059
1060                 if (blacklisted && !first)
1061                         continue;
1062
1063                 sort_iter_add(iter,
1064                               vstruct_idx(i, 0),
1065                               vstruct_last(i));
1066
1067                 nonblacklisted_written = b->written;
1068         }
1069
1070         if (ptr_written) {
1071                 btree_err_on(b->written < ptr_written,
1072                              BTREE_ERR_WANT_RETRY, c, ca, b, NULL,
1073                              "btree node data missing: expected %u sectors, found %u",
1074                              ptr_written, b->written);
1075         } else {
1076                 for (bne = write_block(b);
1077                      bset_byte_offset(b, bne) < btree_bytes(c);
1078                      bne = (void *) bne + block_bytes(c))
1079                         btree_err_on(bne->keys.seq == b->data->keys.seq &&
1080                                      !bch2_journal_seq_is_blacklisted(c,
1081                                                                       le64_to_cpu(bne->keys.journal_seq),
1082                                                                       true),
1083                                      BTREE_ERR_WANT_RETRY, c, ca, b, NULL,
1084                                      "found bset signature after last bset");
1085
1086                 /*
1087                  * Blacklisted bsets are those that were written after the most recent
1088                  * (flush) journal write. Since there wasn't a flush, they may not have
1089                  * made it to all devices - which means we shouldn't write new bsets
1090                  * after them, as that could leave a gap and then reads from that device
1091                  * wouldn't find all the bsets in that btree node - which means it's
1092                  * important that we start writing new bsets after the most recent _non_
1093                  * blacklisted bset:
1094                  */
1095                 blacklisted_written = b->written;
1096                 b->written = nonblacklisted_written;
1097         }
1098
1099         sorted = btree_bounce_alloc(c, btree_bytes(c), &used_mempool);
1100         sorted->keys.u64s = 0;
1101
1102         set_btree_bset(b, b->set, &b->data->keys);
1103
1104         b->nr = bch2_key_sort_fix_overlapping(c, &sorted->keys, iter);
1105
1106         u64s = le16_to_cpu(sorted->keys.u64s);
1107         *sorted = *b->data;
1108         sorted->keys.u64s = cpu_to_le16(u64s);
1109         swap(sorted, b->data);
1110         set_btree_bset(b, b->set, &b->data->keys);
1111         b->nsets = 1;
1112
1113         BUG_ON(b->nr.live_u64s != u64s);
1114
1115         btree_bounce_free(c, btree_bytes(c), used_mempool, sorted);
1116
1117         if (updated_range)
1118                 bch2_btree_node_drop_keys_outside_node(b);
1119
1120         i = &b->data->keys;
1121         for (k = i->start; k != vstruct_last(i);) {
1122                 struct bkey tmp;
1123                 struct bkey_s u = __bkey_disassemble(b, k, &tmp);
1124
1125                 printbuf_reset(&buf);
1126
1127                 if (bch2_bkey_val_invalid(c, u.s_c, READ, &buf) ||
1128                     (bch2_inject_invalid_keys &&
1129                      !bversion_cmp(u.k->version, MAX_VERSION))) {
1130                         printbuf_reset(&buf);
1131
1132                         prt_printf(&buf, "invalid bkey: ");
1133                         bch2_bkey_val_invalid(c, u.s_c, READ, &buf);
1134                         prt_printf(&buf, "\n  ");
1135                         bch2_bkey_val_to_text(&buf, c, u.s_c);
1136
1137                         btree_err(BTREE_ERR_FIXABLE, c, NULL, b, i, "%s", buf.buf);
1138
1139                         btree_keys_account_key_drop(&b->nr, 0, k);
1140
1141                         i->u64s = cpu_to_le16(le16_to_cpu(i->u64s) - k->u64s);
1142                         memmove_u64s_down(k, bkey_p_next(k),
1143                                           (u64 *) vstruct_end(i) - (u64 *) k);
1144                         set_btree_bset_end(b, b->set);
1145                         continue;
1146                 }
1147
1148                 if (u.k->type == KEY_TYPE_btree_ptr_v2) {
1149                         struct bkey_s_btree_ptr_v2 bp = bkey_s_to_btree_ptr_v2(u);
1150
1151                         bp.v->mem_ptr = 0;
1152                 }
1153
1154                 k = bkey_p_next(k);
1155         }
1156
1157         bch2_bset_build_aux_tree(b, b->set, false);
1158
1159         set_needs_whiteout(btree_bset_first(b), true);
1160
1161         btree_node_reset_sib_u64s(b);
1162
1163         bkey_for_each_ptr(bch2_bkey_ptrs(bkey_i_to_s(&b->key)), ptr) {
1164                 struct bch_dev *ca = bch_dev_bkey_exists(c, ptr->dev);
1165
1166                 if (ca->mi.state != BCH_MEMBER_STATE_rw)
1167                         set_btree_node_need_rewrite(b);
1168         }
1169
1170         if (!ptr_written)
1171                 set_btree_node_need_rewrite(b);
1172 out:
1173         mempool_free(iter, &c->fill_iter);
1174         printbuf_exit(&buf);
1175         return retry_read;
1176 fsck_err:
1177         if (ret == BTREE_RETRY_READ)
1178                 retry_read = 1;
1179         else
1180                 set_btree_node_read_error(b);
1181         goto out;
1182 }
1183
1184 static void btree_node_read_work(struct work_struct *work)
1185 {
1186         struct btree_read_bio *rb =
1187                 container_of(work, struct btree_read_bio, work);
1188         struct bch_fs *c        = rb->c;
1189         struct btree *b         = rb->b;
1190         struct bch_dev *ca      = bch_dev_bkey_exists(c, rb->pick.ptr.dev);
1191         struct bio *bio         = &rb->bio;
1192         struct bch_io_failures failed = { .nr = 0 };
1193         struct printbuf buf = PRINTBUF;
1194         bool saw_error = false;
1195         bool retry = false;
1196         bool can_retry;
1197
1198         goto start;
1199         while (1) {
1200                 retry = true;
1201                 bch_info(c, "retrying read");
1202                 ca = bch_dev_bkey_exists(c, rb->pick.ptr.dev);
1203                 rb->have_ioref          = bch2_dev_get_ioref(ca, READ);
1204                 bio_reset(bio, NULL, REQ_OP_READ|REQ_SYNC|REQ_META);
1205                 bio->bi_iter.bi_sector  = rb->pick.ptr.offset;
1206                 bio->bi_iter.bi_size    = btree_bytes(c);
1207
1208                 if (rb->have_ioref) {
1209                         bio_set_dev(bio, ca->disk_sb.bdev);
1210                         submit_bio_wait(bio);
1211                 } else {
1212                         bio->bi_status = BLK_STS_REMOVED;
1213                 }
1214 start:
1215                 printbuf_reset(&buf);
1216                 btree_pos_to_text(&buf, c, b);
1217                 bch2_dev_io_err_on(bio->bi_status, ca, "btree read error %s for %s",
1218                                    bch2_blk_status_to_str(bio->bi_status), buf.buf);
1219                 if (rb->have_ioref)
1220                         percpu_ref_put(&ca->io_ref);
1221                 rb->have_ioref = false;
1222
1223                 bch2_mark_io_failure(&failed, &rb->pick);
1224
1225                 can_retry = bch2_bkey_pick_read_device(c,
1226                                 bkey_i_to_s_c(&b->key),
1227                                 &failed, &rb->pick) > 0;
1228
1229                 if (!bio->bi_status &&
1230                     !bch2_btree_node_read_done(c, ca, b, can_retry, &saw_error)) {
1231                         if (retry)
1232                                 bch_info(c, "retry success");
1233                         break;
1234                 }
1235
1236                 saw_error = true;
1237
1238                 if (!can_retry) {
1239                         set_btree_node_read_error(b);
1240                         break;
1241                 }
1242         }
1243
1244         bch2_time_stats_update(&c->times[BCH_TIME_btree_node_read],
1245                                rb->start_time);
1246         bio_put(&rb->bio);
1247         printbuf_exit(&buf);
1248
1249         if (saw_error && !btree_node_read_error(b)) {
1250                 struct printbuf buf = PRINTBUF;
1251
1252                 bch2_bpos_to_text(&buf, b->key.k.p);
1253                 bch_info(c, "%s: rewriting btree node at btree=%s level=%u %s due to error",
1254                          __func__, bch2_btree_ids[b->c.btree_id], b->c.level, buf.buf);
1255                 printbuf_exit(&buf);
1256
1257                 bch2_btree_node_rewrite_async(c, b);
1258         }
1259
1260         clear_btree_node_read_in_flight(b);
1261         wake_up_bit(&b->flags, BTREE_NODE_read_in_flight);
1262 }
1263
1264 static void btree_node_read_endio(struct bio *bio)
1265 {
1266         struct btree_read_bio *rb =
1267                 container_of(bio, struct btree_read_bio, bio);
1268         struct bch_fs *c        = rb->c;
1269
1270         if (rb->have_ioref) {
1271                 struct bch_dev *ca = bch_dev_bkey_exists(c, rb->pick.ptr.dev);
1272
1273                 bch2_latency_acct(ca, rb->start_time, READ);
1274         }
1275
1276         queue_work(c->io_complete_wq, &rb->work);
1277 }
1278
1279 struct btree_node_read_all {
1280         struct closure          cl;
1281         struct bch_fs           *c;
1282         struct btree            *b;
1283         unsigned                nr;
1284         void                    *buf[BCH_REPLICAS_MAX];
1285         struct bio              *bio[BCH_REPLICAS_MAX];
1286         int                     err[BCH_REPLICAS_MAX];
1287 };
1288
1289 static unsigned btree_node_sectors_written(struct bch_fs *c, void *data)
1290 {
1291         struct btree_node *bn = data;
1292         struct btree_node_entry *bne;
1293         unsigned offset = 0;
1294
1295         if (le64_to_cpu(bn->magic) !=  bset_magic(c))
1296                 return 0;
1297
1298         while (offset < btree_sectors(c)) {
1299                 if (!offset) {
1300                         offset += vstruct_sectors(bn, c->block_bits);
1301                 } else {
1302                         bne = data + (offset << 9);
1303                         if (bne->keys.seq != bn->keys.seq)
1304                                 break;
1305                         offset += vstruct_sectors(bne, c->block_bits);
1306                 }
1307         }
1308
1309         return offset;
1310 }
1311
1312 static bool btree_node_has_extra_bsets(struct bch_fs *c, unsigned offset, void *data)
1313 {
1314         struct btree_node *bn = data;
1315         struct btree_node_entry *bne;
1316
1317         if (!offset)
1318                 return false;
1319
1320         while (offset < btree_sectors(c)) {
1321                 bne = data + (offset << 9);
1322                 if (bne->keys.seq == bn->keys.seq)
1323                         return true;
1324                 offset++;
1325         }
1326
1327         return false;
1328         return offset;
1329 }
1330
1331 static void btree_node_read_all_replicas_done(struct closure *cl)
1332 {
1333         struct btree_node_read_all *ra =
1334                 container_of(cl, struct btree_node_read_all, cl);
1335         struct bch_fs *c = ra->c;
1336         struct btree *b = ra->b;
1337         struct printbuf buf = PRINTBUF;
1338         bool dump_bset_maps = false;
1339         bool have_retry = false;
1340         int ret = 0, best = -1, write = READ;
1341         unsigned i, written = 0, written2 = 0;
1342         __le64 seq = b->key.k.type == KEY_TYPE_btree_ptr_v2
1343                 ? bkey_i_to_btree_ptr_v2(&b->key)->v.seq : 0;
1344         bool _saw_error = false, *saw_error = &_saw_error;
1345
1346         for (i = 0; i < ra->nr; i++) {
1347                 struct btree_node *bn = ra->buf[i];
1348
1349                 if (ra->err[i])
1350                         continue;
1351
1352                 if (le64_to_cpu(bn->magic) != bset_magic(c) ||
1353                     (seq && seq != bn->keys.seq))
1354                         continue;
1355
1356                 if (best < 0) {
1357                         best = i;
1358                         written = btree_node_sectors_written(c, bn);
1359                         continue;
1360                 }
1361
1362                 written2 = btree_node_sectors_written(c, ra->buf[i]);
1363                 if (btree_err_on(written2 != written, BTREE_ERR_FIXABLE, c, NULL, b, NULL,
1364                                  "btree node sectors written mismatch: %u != %u",
1365                                  written, written2) ||
1366                     btree_err_on(btree_node_has_extra_bsets(c, written2, ra->buf[i]),
1367                                  BTREE_ERR_FIXABLE, c, NULL, b, NULL,
1368                                  "found bset signature after last bset") ||
1369                     btree_err_on(memcmp(ra->buf[best], ra->buf[i], written << 9),
1370                                  BTREE_ERR_FIXABLE, c, NULL, b, NULL,
1371                                  "btree node replicas content mismatch"))
1372                         dump_bset_maps = true;
1373
1374                 if (written2 > written) {
1375                         written = written2;
1376                         best = i;
1377                 }
1378         }
1379 fsck_err:
1380         if (dump_bset_maps) {
1381                 for (i = 0; i < ra->nr; i++) {
1382                         struct btree_node *bn = ra->buf[i];
1383                         struct btree_node_entry *bne = NULL;
1384                         unsigned offset = 0, sectors;
1385                         bool gap = false;
1386
1387                         if (ra->err[i])
1388                                 continue;
1389
1390                         printbuf_reset(&buf);
1391
1392                         while (offset < btree_sectors(c)) {
1393                                 if (!offset) {
1394                                         sectors = vstruct_sectors(bn, c->block_bits);
1395                                 } else {
1396                                         bne = ra->buf[i] + (offset << 9);
1397                                         if (bne->keys.seq != bn->keys.seq)
1398                                                 break;
1399                                         sectors = vstruct_sectors(bne, c->block_bits);
1400                                 }
1401
1402                                 prt_printf(&buf, " %u-%u", offset, offset + sectors);
1403                                 if (bne && bch2_journal_seq_is_blacklisted(c,
1404                                                         le64_to_cpu(bne->keys.journal_seq), false))
1405                                         prt_printf(&buf, "*");
1406                                 offset += sectors;
1407                         }
1408
1409                         while (offset < btree_sectors(c)) {
1410                                 bne = ra->buf[i] + (offset << 9);
1411                                 if (bne->keys.seq == bn->keys.seq) {
1412                                         if (!gap)
1413                                                 prt_printf(&buf, " GAP");
1414                                         gap = true;
1415
1416                                         sectors = vstruct_sectors(bne, c->block_bits);
1417                                         prt_printf(&buf, " %u-%u", offset, offset + sectors);
1418                                         if (bch2_journal_seq_is_blacklisted(c,
1419                                                         le64_to_cpu(bne->keys.journal_seq), false))
1420                                                 prt_printf(&buf, "*");
1421                                 }
1422                                 offset++;
1423                         }
1424
1425                         bch_err(c, "replica %u:%s", i, buf.buf);
1426                 }
1427         }
1428
1429         if (best >= 0) {
1430                 memcpy(b->data, ra->buf[best], btree_bytes(c));
1431                 ret = bch2_btree_node_read_done(c, NULL, b, false, saw_error);
1432         } else {
1433                 ret = -1;
1434         }
1435
1436         if (ret)
1437                 set_btree_node_read_error(b);
1438         else if (*saw_error)
1439                 bch2_btree_node_rewrite_async(c, b);
1440
1441         for (i = 0; i < ra->nr; i++) {
1442                 mempool_free(ra->buf[i], &c->btree_bounce_pool);
1443                 bio_put(ra->bio[i]);
1444         }
1445
1446         closure_debug_destroy(&ra->cl);
1447         kfree(ra);
1448         printbuf_exit(&buf);
1449
1450         clear_btree_node_read_in_flight(b);
1451         wake_up_bit(&b->flags, BTREE_NODE_read_in_flight);
1452 }
1453
1454 static void btree_node_read_all_replicas_endio(struct bio *bio)
1455 {
1456         struct btree_read_bio *rb =
1457                 container_of(bio, struct btree_read_bio, bio);
1458         struct bch_fs *c        = rb->c;
1459         struct btree_node_read_all *ra = rb->ra;
1460
1461         if (rb->have_ioref) {
1462                 struct bch_dev *ca = bch_dev_bkey_exists(c, rb->pick.ptr.dev);
1463
1464                 bch2_latency_acct(ca, rb->start_time, READ);
1465         }
1466
1467         ra->err[rb->idx] = bio->bi_status;
1468         closure_put(&ra->cl);
1469 }
1470
1471 /*
1472  * XXX This allocates multiple times from the same mempools, and can deadlock
1473  * under sufficient memory pressure (but is only a debug path)
1474  */
1475 static int btree_node_read_all_replicas(struct bch_fs *c, struct btree *b, bool sync)
1476 {
1477         struct bkey_s_c k = bkey_i_to_s_c(&b->key);
1478         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
1479         const union bch_extent_entry *entry;
1480         struct extent_ptr_decoded pick;
1481         struct btree_node_read_all *ra;
1482         unsigned i;
1483
1484         ra = kzalloc(sizeof(*ra), GFP_NOFS);
1485         if (!ra)
1486                 return -BCH_ERR_ENOMEM_btree_node_read_all_replicas;
1487
1488         closure_init(&ra->cl, NULL);
1489         ra->c   = c;
1490         ra->b   = b;
1491         ra->nr  = bch2_bkey_nr_ptrs(k);
1492
1493         for (i = 0; i < ra->nr; i++) {
1494                 ra->buf[i] = mempool_alloc(&c->btree_bounce_pool, GFP_NOFS);
1495                 ra->bio[i] = bio_alloc_bioset(NULL,
1496                                               buf_pages(ra->buf[i], btree_bytes(c)),
1497                                               REQ_OP_READ|REQ_SYNC|REQ_META,
1498                                               GFP_NOFS,
1499                                               &c->btree_bio);
1500         }
1501
1502         i = 0;
1503         bkey_for_each_ptr_decode(k.k, ptrs, pick, entry) {
1504                 struct bch_dev *ca = bch_dev_bkey_exists(c, pick.ptr.dev);
1505                 struct btree_read_bio *rb =
1506                         container_of(ra->bio[i], struct btree_read_bio, bio);
1507                 rb->c                   = c;
1508                 rb->b                   = b;
1509                 rb->ra                  = ra;
1510                 rb->start_time          = local_clock();
1511                 rb->have_ioref          = bch2_dev_get_ioref(ca, READ);
1512                 rb->idx                 = i;
1513                 rb->pick                = pick;
1514                 rb->bio.bi_iter.bi_sector = pick.ptr.offset;
1515                 rb->bio.bi_end_io       = btree_node_read_all_replicas_endio;
1516                 bch2_bio_map(&rb->bio, ra->buf[i], btree_bytes(c));
1517
1518                 if (rb->have_ioref) {
1519                         this_cpu_add(ca->io_done->sectors[READ][BCH_DATA_btree],
1520                                      bio_sectors(&rb->bio));
1521                         bio_set_dev(&rb->bio, ca->disk_sb.bdev);
1522
1523                         closure_get(&ra->cl);
1524                         submit_bio(&rb->bio);
1525                 } else {
1526                         ra->err[i] = BLK_STS_REMOVED;
1527                 }
1528
1529                 i++;
1530         }
1531
1532         if (sync) {
1533                 closure_sync(&ra->cl);
1534                 btree_node_read_all_replicas_done(&ra->cl);
1535         } else {
1536                 continue_at(&ra->cl, btree_node_read_all_replicas_done,
1537                             c->io_complete_wq);
1538         }
1539
1540         return 0;
1541 }
1542
1543 void bch2_btree_node_read(struct bch_fs *c, struct btree *b,
1544                           bool sync)
1545 {
1546         struct extent_ptr_decoded pick;
1547         struct btree_read_bio *rb;
1548         struct bch_dev *ca;
1549         struct bio *bio;
1550         int ret;
1551
1552         trace_and_count(c, btree_node_read, c, b);
1553
1554         if (bch2_verify_all_btree_replicas &&
1555             !btree_node_read_all_replicas(c, b, sync))
1556                 return;
1557
1558         ret = bch2_bkey_pick_read_device(c, bkey_i_to_s_c(&b->key),
1559                                          NULL, &pick);
1560
1561         if (ret <= 0) {
1562                 struct printbuf buf = PRINTBUF;
1563
1564                 prt_str(&buf, "btree node read error: no device to read from\n at ");
1565                 btree_pos_to_text(&buf, c, b);
1566                 bch_err(c, "%s", buf.buf);
1567
1568                 if (test_bit(BCH_FS_TOPOLOGY_REPAIR_DONE, &c->flags))
1569                         bch2_fatal_error(c);
1570
1571                 set_btree_node_read_error(b);
1572                 clear_btree_node_read_in_flight(b);
1573                 wake_up_bit(&b->flags, BTREE_NODE_read_in_flight);
1574                 printbuf_exit(&buf);
1575                 return;
1576         }
1577
1578         ca = bch_dev_bkey_exists(c, pick.ptr.dev);
1579
1580         bio = bio_alloc_bioset(NULL,
1581                                buf_pages(b->data, btree_bytes(c)),
1582                                REQ_OP_READ|REQ_SYNC|REQ_META,
1583                                GFP_NOIO,
1584                                &c->btree_bio);
1585         rb = container_of(bio, struct btree_read_bio, bio);
1586         rb->c                   = c;
1587         rb->b                   = b;
1588         rb->ra                  = NULL;
1589         rb->start_time          = local_clock();
1590         rb->have_ioref          = bch2_dev_get_ioref(ca, READ);
1591         rb->pick                = pick;
1592         INIT_WORK(&rb->work, btree_node_read_work);
1593         bio->bi_iter.bi_sector  = pick.ptr.offset;
1594         bio->bi_end_io          = btree_node_read_endio;
1595         bch2_bio_map(bio, b->data, btree_bytes(c));
1596
1597         if (rb->have_ioref) {
1598                 this_cpu_add(ca->io_done->sectors[READ][BCH_DATA_btree],
1599                              bio_sectors(bio));
1600                 bio_set_dev(bio, ca->disk_sb.bdev);
1601
1602                 if (sync) {
1603                         submit_bio_wait(bio);
1604
1605                         btree_node_read_work(&rb->work);
1606                 } else {
1607                         submit_bio(bio);
1608                 }
1609         } else {
1610                 bio->bi_status = BLK_STS_REMOVED;
1611
1612                 if (sync)
1613                         btree_node_read_work(&rb->work);
1614                 else
1615                         queue_work(c->io_complete_wq, &rb->work);
1616         }
1617 }
1618
1619 static int __bch2_btree_root_read(struct btree_trans *trans, enum btree_id id,
1620                                   const struct bkey_i *k, unsigned level)
1621 {
1622         struct bch_fs *c = trans->c;
1623         struct closure cl;
1624         struct btree *b;
1625         int ret;
1626
1627         closure_init_stack(&cl);
1628
1629         do {
1630                 ret = bch2_btree_cache_cannibalize_lock(c, &cl);
1631                 closure_sync(&cl);
1632         } while (ret);
1633
1634         b = bch2_btree_node_mem_alloc(trans, level != 0);
1635         bch2_btree_cache_cannibalize_unlock(c);
1636
1637         BUG_ON(IS_ERR(b));
1638
1639         bkey_copy(&b->key, k);
1640         BUG_ON(bch2_btree_node_hash_insert(&c->btree_cache, b, level, id));
1641
1642         set_btree_node_read_in_flight(b);
1643
1644         bch2_btree_node_read(c, b, true);
1645
1646         if (btree_node_read_error(b)) {
1647                 bch2_btree_node_hash_remove(&c->btree_cache, b);
1648
1649                 mutex_lock(&c->btree_cache.lock);
1650                 list_move(&b->list, &c->btree_cache.freeable);
1651                 mutex_unlock(&c->btree_cache.lock);
1652
1653                 ret = -EIO;
1654                 goto err;
1655         }
1656
1657         bch2_btree_set_root_for_read(c, b);
1658 err:
1659         six_unlock_write(&b->c.lock);
1660         six_unlock_intent(&b->c.lock);
1661
1662         return ret;
1663 }
1664
1665 int bch2_btree_root_read(struct bch_fs *c, enum btree_id id,
1666                         const struct bkey_i *k, unsigned level)
1667 {
1668         return bch2_trans_run(c, __bch2_btree_root_read(&trans, id, k, level));
1669
1670 }
1671
1672 void bch2_btree_complete_write(struct bch_fs *c, struct btree *b,
1673                               struct btree_write *w)
1674 {
1675         unsigned long old, new, v = READ_ONCE(b->will_make_reachable);
1676
1677         do {
1678                 old = new = v;
1679                 if (!(old & 1))
1680                         break;
1681
1682                 new &= ~1UL;
1683         } while ((v = cmpxchg(&b->will_make_reachable, old, new)) != old);
1684
1685         if (old & 1)
1686                 closure_put(&((struct btree_update *) new)->cl);
1687
1688         bch2_journal_pin_drop(&c->journal, &w->journal);
1689 }
1690
1691 static void __btree_node_write_done(struct bch_fs *c, struct btree *b)
1692 {
1693         struct btree_write *w = btree_prev_write(b);
1694         unsigned long old, new, v;
1695         unsigned type = 0;
1696
1697         bch2_btree_complete_write(c, b, w);
1698
1699         v = READ_ONCE(b->flags);
1700         do {
1701                 old = new = v;
1702
1703                 if ((old & (1U << BTREE_NODE_dirty)) &&
1704                     (old & (1U << BTREE_NODE_need_write)) &&
1705                     !(old & (1U << BTREE_NODE_never_write)) &&
1706                     !(old & (1U << BTREE_NODE_write_blocked)) &&
1707                     !(old & (1U << BTREE_NODE_will_make_reachable))) {
1708                         new &= ~(1U << BTREE_NODE_dirty);
1709                         new &= ~(1U << BTREE_NODE_need_write);
1710                         new |=  (1U << BTREE_NODE_write_in_flight);
1711                         new |=  (1U << BTREE_NODE_write_in_flight_inner);
1712                         new |=  (1U << BTREE_NODE_just_written);
1713                         new ^=  (1U << BTREE_NODE_write_idx);
1714
1715                         type = new & BTREE_WRITE_TYPE_MASK;
1716                         new &= ~BTREE_WRITE_TYPE_MASK;
1717                 } else {
1718                         new &= ~(1U << BTREE_NODE_write_in_flight);
1719                         new &= ~(1U << BTREE_NODE_write_in_flight_inner);
1720                 }
1721         } while ((v = cmpxchg(&b->flags, old, new)) != old);
1722
1723         if (new & (1U << BTREE_NODE_write_in_flight))
1724                 __bch2_btree_node_write(c, b, BTREE_WRITE_ALREADY_STARTED|type);
1725         else
1726                 wake_up_bit(&b->flags, BTREE_NODE_write_in_flight);
1727 }
1728
1729 static void btree_node_write_done(struct bch_fs *c, struct btree *b)
1730 {
1731         struct btree_trans trans;
1732
1733         bch2_trans_init(&trans, c, 0, 0);
1734
1735         btree_node_lock_nopath_nofail(&trans, &b->c, SIX_LOCK_read);
1736         __btree_node_write_done(c, b);
1737         six_unlock_read(&b->c.lock);
1738
1739         bch2_trans_exit(&trans);
1740 }
1741
1742 static void btree_node_write_work(struct work_struct *work)
1743 {
1744         struct btree_write_bio *wbio =
1745                 container_of(work, struct btree_write_bio, work);
1746         struct bch_fs *c        = wbio->wbio.c;
1747         struct btree *b         = wbio->wbio.bio.bi_private;
1748         struct bch_extent_ptr *ptr;
1749         int ret = 0;
1750
1751         btree_bounce_free(c,
1752                 wbio->data_bytes,
1753                 wbio->wbio.used_mempool,
1754                 wbio->data);
1755
1756         bch2_bkey_drop_ptrs(bkey_i_to_s(&wbio->key), ptr,
1757                 bch2_dev_list_has_dev(wbio->wbio.failed, ptr->dev));
1758
1759         if (!bch2_bkey_nr_ptrs(bkey_i_to_s_c(&wbio->key)))
1760                 goto err;
1761
1762         if (wbio->wbio.first_btree_write) {
1763                 if (wbio->wbio.failed.nr) {
1764
1765                 }
1766         } else {
1767                 ret = bch2_trans_do(c, NULL, NULL, 0,
1768                         bch2_btree_node_update_key_get_iter(&trans, b, &wbio->key,
1769                                                             !wbio->wbio.failed.nr));
1770                 if (ret)
1771                         goto err;
1772         }
1773 out:
1774         bio_put(&wbio->wbio.bio);
1775         btree_node_write_done(c, b);
1776         return;
1777 err:
1778         set_btree_node_noevict(b);
1779         if (!bch2_err_matches(ret, EROFS))
1780                 bch2_fs_fatal_error(c, "fatal error writing btree node");
1781         goto out;
1782 }
1783
1784 static void btree_node_write_endio(struct bio *bio)
1785 {
1786         struct bch_write_bio *wbio      = to_wbio(bio);
1787         struct bch_write_bio *parent    = wbio->split ? wbio->parent : NULL;
1788         struct bch_write_bio *orig      = parent ?: wbio;
1789         struct btree_write_bio *wb      = container_of(orig, struct btree_write_bio, wbio);
1790         struct bch_fs *c                = wbio->c;
1791         struct btree *b                 = wbio->bio.bi_private;
1792         struct bch_dev *ca              = bch_dev_bkey_exists(c, wbio->dev);
1793         unsigned long flags;
1794
1795         if (wbio->have_ioref)
1796                 bch2_latency_acct(ca, wbio->submit_time, WRITE);
1797
1798         if (bch2_dev_io_err_on(bio->bi_status, ca, "btree write error: %s",
1799                                bch2_blk_status_to_str(bio->bi_status)) ||
1800             bch2_meta_write_fault("btree")) {
1801                 spin_lock_irqsave(&c->btree_write_error_lock, flags);
1802                 bch2_dev_list_add_dev(&orig->failed, wbio->dev);
1803                 spin_unlock_irqrestore(&c->btree_write_error_lock, flags);
1804         }
1805
1806         if (wbio->have_ioref)
1807                 percpu_ref_put(&ca->io_ref);
1808
1809         if (parent) {
1810                 bio_put(bio);
1811                 bio_endio(&parent->bio);
1812                 return;
1813         }
1814
1815         clear_btree_node_write_in_flight_inner(b);
1816         wake_up_bit(&b->flags, BTREE_NODE_write_in_flight_inner);
1817         INIT_WORK(&wb->work, btree_node_write_work);
1818         queue_work(c->btree_io_complete_wq, &wb->work);
1819 }
1820
1821 static int validate_bset_for_write(struct bch_fs *c, struct btree *b,
1822                                    struct bset *i, unsigned sectors)
1823 {
1824         struct printbuf buf = PRINTBUF;
1825         bool saw_error;
1826         int ret;
1827
1828         ret = bch2_bkey_invalid(c, bkey_i_to_s_c(&b->key),
1829                                 BKEY_TYPE_btree, WRITE, &buf);
1830
1831         if (ret)
1832                 bch2_fs_inconsistent(c, "invalid btree node key before write: %s", buf.buf);
1833         printbuf_exit(&buf);
1834         if (ret)
1835                 return ret;
1836
1837         ret = validate_bset_keys(c, b, i, WRITE, false, &saw_error) ?:
1838                 validate_bset(c, NULL, b, i, b->written, sectors, WRITE, false, &saw_error);
1839         if (ret) {
1840                 bch2_inconsistent_error(c);
1841                 dump_stack();
1842         }
1843
1844         return ret;
1845 }
1846
1847 static void btree_write_submit(struct work_struct *work)
1848 {
1849         struct btree_write_bio *wbio = container_of(work, struct btree_write_bio, work);
1850         struct bch_extent_ptr *ptr;
1851         BKEY_PADDED_ONSTACK(k, BKEY_BTREE_PTR_VAL_U64s_MAX) tmp;
1852
1853         bkey_copy(&tmp.k, &wbio->key);
1854
1855         bkey_for_each_ptr(bch2_bkey_ptrs(bkey_i_to_s(&tmp.k)), ptr)
1856                 ptr->offset += wbio->sector_offset;
1857
1858         bch2_submit_wbio_replicas(&wbio->wbio, wbio->wbio.c, BCH_DATA_btree,
1859                                   &tmp.k, false);
1860 }
1861
1862 void __bch2_btree_node_write(struct bch_fs *c, struct btree *b, unsigned flags)
1863 {
1864         struct btree_write_bio *wbio;
1865         struct bset_tree *t;
1866         struct bset *i;
1867         struct btree_node *bn = NULL;
1868         struct btree_node_entry *bne = NULL;
1869         struct sort_iter sort_iter;
1870         struct nonce nonce;
1871         unsigned bytes_to_write, sectors_to_write, bytes, u64s;
1872         u64 seq = 0;
1873         bool used_mempool;
1874         unsigned long old, new;
1875         bool validate_before_checksum = false;
1876         enum btree_write_type type = flags & BTREE_WRITE_TYPE_MASK;
1877         void *data;
1878         int ret;
1879
1880         if (flags & BTREE_WRITE_ALREADY_STARTED)
1881                 goto do_write;
1882
1883         /*
1884          * We may only have a read lock on the btree node - the dirty bit is our
1885          * "lock" against racing with other threads that may be trying to start
1886          * a write, we do a write iff we clear the dirty bit. Since setting the
1887          * dirty bit requires a write lock, we can't race with other threads
1888          * redirtying it:
1889          */
1890         do {
1891                 old = new = READ_ONCE(b->flags);
1892
1893                 if (!(old & (1 << BTREE_NODE_dirty)))
1894                         return;
1895
1896                 if ((flags & BTREE_WRITE_ONLY_IF_NEED) &&
1897                     !(old & (1 << BTREE_NODE_need_write)))
1898                         return;
1899
1900                 if (old &
1901                     ((1 << BTREE_NODE_never_write)|
1902                      (1 << BTREE_NODE_write_blocked)))
1903                         return;
1904
1905                 if (b->written &&
1906                     (old & (1 << BTREE_NODE_will_make_reachable)))
1907                         return;
1908
1909                 if (old & (1 << BTREE_NODE_write_in_flight))
1910                         return;
1911
1912                 if (flags & BTREE_WRITE_ONLY_IF_NEED)
1913                         type = new & BTREE_WRITE_TYPE_MASK;
1914                 new &= ~BTREE_WRITE_TYPE_MASK;
1915
1916                 new &= ~(1 << BTREE_NODE_dirty);
1917                 new &= ~(1 << BTREE_NODE_need_write);
1918                 new |=  (1 << BTREE_NODE_write_in_flight);
1919                 new |=  (1 << BTREE_NODE_write_in_flight_inner);
1920                 new |=  (1 << BTREE_NODE_just_written);
1921                 new ^=  (1 << BTREE_NODE_write_idx);
1922         } while (cmpxchg_acquire(&b->flags, old, new) != old);
1923
1924         if (new & (1U << BTREE_NODE_need_write))
1925                 return;
1926 do_write:
1927         BUG_ON((type == BTREE_WRITE_initial) != (b->written == 0));
1928
1929         atomic_dec(&c->btree_cache.dirty);
1930
1931         BUG_ON(btree_node_fake(b));
1932         BUG_ON((b->will_make_reachable != 0) != !b->written);
1933
1934         BUG_ON(b->written >= btree_sectors(c));
1935         BUG_ON(b->written & (block_sectors(c) - 1));
1936         BUG_ON(bset_written(b, btree_bset_last(b)));
1937         BUG_ON(le64_to_cpu(b->data->magic) != bset_magic(c));
1938         BUG_ON(memcmp(&b->data->format, &b->format, sizeof(b->format)));
1939
1940         bch2_sort_whiteouts(c, b);
1941
1942         sort_iter_init(&sort_iter, b);
1943
1944         bytes = !b->written
1945                 ? sizeof(struct btree_node)
1946                 : sizeof(struct btree_node_entry);
1947
1948         bytes += b->whiteout_u64s * sizeof(u64);
1949
1950         for_each_bset(b, t) {
1951                 i = bset(b, t);
1952
1953                 if (bset_written(b, i))
1954                         continue;
1955
1956                 bytes += le16_to_cpu(i->u64s) * sizeof(u64);
1957                 sort_iter_add(&sort_iter,
1958                               btree_bkey_first(b, t),
1959                               btree_bkey_last(b, t));
1960                 seq = max(seq, le64_to_cpu(i->journal_seq));
1961         }
1962
1963         BUG_ON(b->written && !seq);
1964
1965         /* bch2_varint_decode may read up to 7 bytes past the end of the buffer: */
1966         bytes += 8;
1967
1968         /* buffer must be a multiple of the block size */
1969         bytes = round_up(bytes, block_bytes(c));
1970
1971         data = btree_bounce_alloc(c, bytes, &used_mempool);
1972
1973         if (!b->written) {
1974                 bn = data;
1975                 *bn = *b->data;
1976                 i = &bn->keys;
1977         } else {
1978                 bne = data;
1979                 bne->keys = b->data->keys;
1980                 i = &bne->keys;
1981         }
1982
1983         i->journal_seq  = cpu_to_le64(seq);
1984         i->u64s         = 0;
1985
1986         sort_iter_add(&sort_iter,
1987                       unwritten_whiteouts_start(c, b),
1988                       unwritten_whiteouts_end(c, b));
1989         SET_BSET_SEPARATE_WHITEOUTS(i, false);
1990
1991         b->whiteout_u64s = 0;
1992
1993         u64s = bch2_sort_keys(i->start, &sort_iter, false);
1994         le16_add_cpu(&i->u64s, u64s);
1995
1996         BUG_ON(!b->written && i->u64s != b->data->keys.u64s);
1997
1998         set_needs_whiteout(i, false);
1999
2000         /* do we have data to write? */
2001         if (b->written && !i->u64s)
2002                 goto nowrite;
2003
2004         bytes_to_write = vstruct_end(i) - data;
2005         sectors_to_write = round_up(bytes_to_write, block_bytes(c)) >> 9;
2006
2007         if (!b->written &&
2008             b->key.k.type == KEY_TYPE_btree_ptr_v2)
2009                 BUG_ON(btree_ptr_sectors_written(&b->key) != sectors_to_write);
2010
2011         memset(data + bytes_to_write, 0,
2012                (sectors_to_write << 9) - bytes_to_write);
2013
2014         BUG_ON(b->written + sectors_to_write > btree_sectors(c));
2015         BUG_ON(BSET_BIG_ENDIAN(i) != CPU_BIG_ENDIAN);
2016         BUG_ON(i->seq != b->data->keys.seq);
2017
2018         i->version = c->sb.version < bcachefs_metadata_version_bkey_renumber
2019                 ? cpu_to_le16(BCH_BSET_VERSION_OLD)
2020                 : cpu_to_le16(c->sb.version);
2021         SET_BSET_OFFSET(i, b->written);
2022         SET_BSET_CSUM_TYPE(i, bch2_meta_checksum_type(c));
2023
2024         if (bch2_csum_type_is_encryption(BSET_CSUM_TYPE(i)))
2025                 validate_before_checksum = true;
2026
2027         /* validate_bset will be modifying: */
2028         if (le16_to_cpu(i->version) < bcachefs_metadata_version_current)
2029                 validate_before_checksum = true;
2030
2031         /* if we're going to be encrypting, check metadata validity first: */
2032         if (validate_before_checksum &&
2033             validate_bset_for_write(c, b, i, sectors_to_write))
2034                 goto err;
2035
2036         ret = bset_encrypt(c, i, b->written << 9);
2037         if (bch2_fs_fatal_err_on(ret, c,
2038                         "error encrypting btree node: %i\n", ret))
2039                 goto err;
2040
2041         nonce = btree_nonce(i, b->written << 9);
2042
2043         if (bn)
2044                 bn->csum = csum_vstruct(c, BSET_CSUM_TYPE(i), nonce, bn);
2045         else
2046                 bne->csum = csum_vstruct(c, BSET_CSUM_TYPE(i), nonce, bne);
2047
2048         /* if we're not encrypting, check metadata after checksumming: */
2049         if (!validate_before_checksum &&
2050             validate_bset_for_write(c, b, i, sectors_to_write))
2051                 goto err;
2052
2053         /*
2054          * We handle btree write errors by immediately halting the journal -
2055          * after we've done that, we can't issue any subsequent btree writes
2056          * because they might have pointers to new nodes that failed to write.
2057          *
2058          * Furthermore, there's no point in doing any more btree writes because
2059          * with the journal stopped, we're never going to update the journal to
2060          * reflect that those writes were done and the data flushed from the
2061          * journal:
2062          *
2063          * Also on journal error, the pending write may have updates that were
2064          * never journalled (interior nodes, see btree_update_nodes_written()) -
2065          * it's critical that we don't do the write in that case otherwise we
2066          * will have updates visible that weren't in the journal:
2067          *
2068          * Make sure to update b->written so bch2_btree_init_next() doesn't
2069          * break:
2070          */
2071         if (bch2_journal_error(&c->journal) ||
2072             c->opts.nochanges)
2073                 goto err;
2074
2075         trace_and_count(c, btree_node_write, b, bytes_to_write, sectors_to_write);
2076
2077         wbio = container_of(bio_alloc_bioset(NULL,
2078                                 buf_pages(data, sectors_to_write << 9),
2079                                 REQ_OP_WRITE|REQ_META,
2080                                 GFP_NOIO,
2081                                 &c->btree_bio),
2082                             struct btree_write_bio, wbio.bio);
2083         wbio_init(&wbio->wbio.bio);
2084         wbio->data                      = data;
2085         wbio->data_bytes                = bytes;
2086         wbio->sector_offset             = b->written;
2087         wbio->wbio.c                    = c;
2088         wbio->wbio.used_mempool         = used_mempool;
2089         wbio->wbio.first_btree_write    = !b->written;
2090         wbio->wbio.bio.bi_end_io        = btree_node_write_endio;
2091         wbio->wbio.bio.bi_private       = b;
2092
2093         bch2_bio_map(&wbio->wbio.bio, data, sectors_to_write << 9);
2094
2095         bkey_copy(&wbio->key, &b->key);
2096
2097         b->written += sectors_to_write;
2098
2099         if (wbio->key.k.type == KEY_TYPE_btree_ptr_v2)
2100                 bkey_i_to_btree_ptr_v2(&wbio->key)->v.sectors_written =
2101                         cpu_to_le16(b->written);
2102
2103         atomic64_inc(&c->btree_write_stats[type].nr);
2104         atomic64_add(bytes_to_write, &c->btree_write_stats[type].bytes);
2105
2106         INIT_WORK(&wbio->work, btree_write_submit);
2107         queue_work(c->io_complete_wq, &wbio->work);
2108         return;
2109 err:
2110         set_btree_node_noevict(b);
2111         b->written += sectors_to_write;
2112 nowrite:
2113         btree_bounce_free(c, bytes, used_mempool, data);
2114         __btree_node_write_done(c, b);
2115 }
2116
2117 /*
2118  * Work that must be done with write lock held:
2119  */
2120 bool bch2_btree_post_write_cleanup(struct bch_fs *c, struct btree *b)
2121 {
2122         bool invalidated_iter = false;
2123         struct btree_node_entry *bne;
2124         struct bset_tree *t;
2125
2126         if (!btree_node_just_written(b))
2127                 return false;
2128
2129         BUG_ON(b->whiteout_u64s);
2130
2131         clear_btree_node_just_written(b);
2132
2133         /*
2134          * Note: immediately after write, bset_written() doesn't work - the
2135          * amount of data we had to write after compaction might have been
2136          * smaller than the offset of the last bset.
2137          *
2138          * However, we know that all bsets have been written here, as long as
2139          * we're still holding the write lock:
2140          */
2141
2142         /*
2143          * XXX: decide if we really want to unconditionally sort down to a
2144          * single bset:
2145          */
2146         if (b->nsets > 1) {
2147                 btree_node_sort(c, b, 0, b->nsets, true);
2148                 invalidated_iter = true;
2149         } else {
2150                 invalidated_iter = bch2_drop_whiteouts(b, COMPACT_ALL);
2151         }
2152
2153         for_each_bset(b, t)
2154                 set_needs_whiteout(bset(b, t), true);
2155
2156         bch2_btree_verify(c, b);
2157
2158         /*
2159          * If later we don't unconditionally sort down to a single bset, we have
2160          * to ensure this is still true:
2161          */
2162         BUG_ON((void *) btree_bkey_last(b, bset_tree_last(b)) > write_block(b));
2163
2164         bne = want_new_bset(c, b);
2165         if (bne)
2166                 bch2_bset_init_next(c, b, bne);
2167
2168         bch2_btree_build_aux_trees(b);
2169
2170         return invalidated_iter;
2171 }
2172
2173 /*
2174  * Use this one if the node is intent locked:
2175  */
2176 void bch2_btree_node_write(struct bch_fs *c, struct btree *b,
2177                            enum six_lock_type lock_type_held,
2178                            unsigned flags)
2179 {
2180         if (lock_type_held == SIX_LOCK_intent ||
2181             (lock_type_held == SIX_LOCK_read &&
2182              six_lock_tryupgrade(&b->c.lock))) {
2183                 __bch2_btree_node_write(c, b, flags);
2184
2185                 /* don't cycle lock unnecessarily: */
2186                 if (btree_node_just_written(b) &&
2187                     six_trylock_write(&b->c.lock)) {
2188                         bch2_btree_post_write_cleanup(c, b);
2189                         six_unlock_write(&b->c.lock);
2190                 }
2191
2192                 if (lock_type_held == SIX_LOCK_read)
2193                         six_lock_downgrade(&b->c.lock);
2194         } else {
2195                 __bch2_btree_node_write(c, b, flags);
2196                 if (lock_type_held == SIX_LOCK_write &&
2197                     btree_node_just_written(b))
2198                         bch2_btree_post_write_cleanup(c, b);
2199         }
2200 }
2201
2202 static bool __bch2_btree_flush_all(struct bch_fs *c, unsigned flag)
2203 {
2204         struct bucket_table *tbl;
2205         struct rhash_head *pos;
2206         struct btree *b;
2207         unsigned i;
2208         bool ret = false;
2209 restart:
2210         rcu_read_lock();
2211         for_each_cached_btree(b, c, tbl, i, pos)
2212                 if (test_bit(flag, &b->flags)) {
2213                         rcu_read_unlock();
2214                         wait_on_bit_io(&b->flags, flag, TASK_UNINTERRUPTIBLE);
2215                         ret = true;
2216                         goto restart;
2217                 }
2218         rcu_read_unlock();
2219
2220         return ret;
2221 }
2222
2223 bool bch2_btree_flush_all_reads(struct bch_fs *c)
2224 {
2225         return __bch2_btree_flush_all(c, BTREE_NODE_read_in_flight);
2226 }
2227
2228 bool bch2_btree_flush_all_writes(struct bch_fs *c)
2229 {
2230         return __bch2_btree_flush_all(c, BTREE_NODE_write_in_flight);
2231 }
2232
2233 const char * const bch2_btree_write_types[] = {
2234 #define x(t, n) [n] = #t,
2235         BCH_BTREE_WRITE_TYPES()
2236         NULL
2237 };
2238
2239 void bch2_btree_write_stats_to_text(struct printbuf *out, struct bch_fs *c)
2240 {
2241         printbuf_tabstop_push(out, 20);
2242         printbuf_tabstop_push(out, 10);
2243
2244         prt_tab(out);
2245         prt_str(out, "nr");
2246         prt_tab(out);
2247         prt_str(out, "size");
2248         prt_newline(out);
2249
2250         for (unsigned i = 0; i < BTREE_WRITE_TYPE_NR; i++) {
2251                 u64 nr          = atomic64_read(&c->btree_write_stats[i].nr);
2252                 u64 bytes       = atomic64_read(&c->btree_write_stats[i].bytes);
2253
2254                 prt_printf(out, "%s:", bch2_btree_write_types[i]);
2255                 prt_tab(out);
2256                 prt_u64(out, nr);
2257                 prt_tab(out);
2258                 prt_human_readable_u64(out, nr ? div64_u64(bytes, nr) : 0);
2259                 prt_newline(out);
2260         }
2261 }